* [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver
@ 2018-04-16 6:24 Oleksandr Andrushchenko
2018-04-16 6:24 ` [PATCH v2 1/5] ALSA: xen-front: Introduce Xen para-virtualized sound " Oleksandr Andrushchenko
` (7 more replies)
0 siblings, 8 replies; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-16 6:24 UTC (permalink / raw)
To: xen-devel, linux-kernel, alsa-devel, jgross, boris.ostrovsky,
konrad.wilk, perex, tiwai
Cc: andr2000, Oleksandr Andrushchenko
From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Please note: this patch series depends on [3].
This patch series adds support for Xen [1] para-virtualized
sound frontend driver. It implements the protocol from
include/xen/interface/io/sndif.h with the following limitations:
- mute/unmute is not supported
- get/set volume is not supported
Volume control is not supported for the reason that most of the
use-cases (at the moment) are based on scenarious where
unprivileged OS (e.g. Android, AGL etc) use software mixers.
Both capture and playback are supported.
Corresponding backend, implemented as a user-space application, can be
found at [2].
Thank you,
Oleksandr
Changes since v1:
*****************
1. Moved driver from sound/drivers to sound/xen
2. Coding style changes to better meet Linux Kernel
3. Added explicit back and front synchronization
In order to provide explicit synchronization between backend and
frontend the following changes are introduced in the protocol:
- add new ring buffer for sending asynchronous events from
backend to frontend to report number of bytes played by the
frontend (XENSND_EVT_CUR_POS)
- introduce trigger events for playback control: start/stop/pause/resume
- add "req-" prefix to event-channel and ring-ref to unify naming
of the Xen event channels for requests and events
4. Added explicit back and front parameter negotiation
In order to provide explicit stream parameter negotiation between
backend and frontend the following changes are introduced in the protocol:
add XENSND_OP_HW_PARAM_QUERY request to read/update
configuration space for the parameters given: request passes
desired parameter's intervals/masks and the response to this request
returns allowed min/max intervals/masks to be used.
[1] https://xenproject.org/
[2] https://github.com/xen-troops/snd_be
[3] https://lkml.org/lkml/2018/4/12/522
Oleksandr Andrushchenko (5):
ALSA: xen-front: Introduce Xen para-virtualized sound frontend driver
ALSA: xen-front: Read sound driver configuration from Xen store
ALSA: xen-front: Implement Xen event channel handling
ALSA: xen-front: Implement handling of shared buffers
ALSA: xen-front: Implement ALSA virtual sound driver
sound/Kconfig | 2 +
sound/Makefile | 2 +-
sound/xen/Kconfig | 10 +
sound/xen/Makefile | 9 +
sound/xen/xen_snd_front.c | 410 +++++++++++++++++++
sound/xen/xen_snd_front.h | 57 +++
sound/xen/xen_snd_front_alsa.c | 830 ++++++++++++++++++++++++++++++++++++++
sound/xen/xen_snd_front_alsa.h | 23 ++
sound/xen/xen_snd_front_cfg.c | 517 ++++++++++++++++++++++++
sound/xen/xen_snd_front_cfg.h | 46 +++
sound/xen/xen_snd_front_evtchnl.c | 478 ++++++++++++++++++++++
sound/xen/xen_snd_front_evtchnl.h | 92 +++++
sound/xen/xen_snd_front_shbuf.c | 193 +++++++++
sound/xen/xen_snd_front_shbuf.h | 36 ++
14 files changed, 2704 insertions(+), 1 deletion(-)
create mode 100644 sound/xen/Kconfig
create mode 100644 sound/xen/Makefile
create mode 100644 sound/xen/xen_snd_front.c
create mode 100644 sound/xen/xen_snd_front.h
create mode 100644 sound/xen/xen_snd_front_alsa.c
create mode 100644 sound/xen/xen_snd_front_alsa.h
create mode 100644 sound/xen/xen_snd_front_cfg.c
create mode 100644 sound/xen/xen_snd_front_cfg.h
create mode 100644 sound/xen/xen_snd_front_evtchnl.c
create mode 100644 sound/xen/xen_snd_front_evtchnl.h
create mode 100644 sound/xen/xen_snd_front_shbuf.c
create mode 100644 sound/xen/xen_snd_front_shbuf.h
--
2.16.2
^ permalink raw reply [flat|nested] 40+ messages in thread
* [PATCH v2 1/5] ALSA: xen-front: Introduce Xen para-virtualized sound frontend driver
2018-04-16 6:24 [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver Oleksandr Andrushchenko
@ 2018-04-16 6:24 ` Oleksandr Andrushchenko
2018-04-16 12:25 ` Juergen Gross
2018-04-24 13:55 ` Takashi Iwai
2018-04-16 6:24 ` [PATCH v2 2/5] ALSA: xen-front: Read sound driver configuration from Xen store Oleksandr Andrushchenko
` (6 subsequent siblings)
7 siblings, 2 replies; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-16 6:24 UTC (permalink / raw)
To: xen-devel, linux-kernel, alsa-devel, jgross, boris.ostrovsky,
konrad.wilk, perex, tiwai
Cc: andr2000, Oleksandr Andrushchenko
From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Introduce skeleton of the para-virtualized Xen sound
frontend driver.
Initial handling for Xen bus states: implement
Xen bus state machine for the frontend driver according to
the state diagram and recovery flow from sound para-virtualized
protocol: xen/interface/io/sndif.h.
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
---
sound/Kconfig | 2 +
sound/Makefile | 2 +-
sound/xen/Kconfig | 10 +++
sound/xen/Makefile | 5 ++
sound/xen/xen_snd_front.c | 196 ++++++++++++++++++++++++++++++++++++++++++++++
sound/xen/xen_snd_front.h | 18 +++++
6 files changed, 232 insertions(+), 1 deletion(-)
create mode 100644 sound/xen/Kconfig
create mode 100644 sound/xen/Makefile
create mode 100644 sound/xen/xen_snd_front.c
create mode 100644 sound/xen/xen_snd_front.h
diff --git a/sound/Kconfig b/sound/Kconfig
index 6833db9002ec..1140e9988fc5 100644
--- a/sound/Kconfig
+++ b/sound/Kconfig
@@ -96,6 +96,8 @@ source "sound/x86/Kconfig"
source "sound/synth/Kconfig"
+source "sound/xen/Kconfig"
+
endif # SND
endif # !UML
diff --git a/sound/Makefile b/sound/Makefile
index 99d8c31262c8..797ecdcd35e2 100644
--- a/sound/Makefile
+++ b/sound/Makefile
@@ -5,7 +5,7 @@
obj-$(CONFIG_SOUND) += soundcore.o
obj-$(CONFIG_DMASOUND) += oss/dmasound/
obj-$(CONFIG_SND) += core/ i2c/ drivers/ isa/ pci/ ppc/ arm/ sh/ synth/ usb/ \
- firewire/ sparc/ spi/ parisc/ pcmcia/ mips/ soc/ atmel/ hda/ x86/
+ firewire/ sparc/ spi/ parisc/ pcmcia/ mips/ soc/ atmel/ hda/ x86/ xen/
obj-$(CONFIG_SND_AOA) += aoa/
# This one must be compilable even if sound is configured out
diff --git a/sound/xen/Kconfig b/sound/xen/Kconfig
new file mode 100644
index 000000000000..7cad38be8317
--- /dev/null
+++ b/sound/xen/Kconfig
@@ -0,0 +1,10 @@
+# ALSA Xen drivers
+
+config SND_XEN_FRONTEND
+ tristate "Xen para-virtualized sound frontend driver"
+ depends on XEN && SND_PCM
+ select XEN_XENBUS_FRONTEND
+ default n
+ help
+ Choose this option if you want to enable a para-virtualized
+ frontend sound driver for Xen guest OSes.
diff --git a/sound/xen/Makefile b/sound/xen/Makefile
new file mode 100644
index 000000000000..4507ef3c27fd
--- /dev/null
+++ b/sound/xen/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0 OR MIT
+
+snd_xen_front-objs := xen_snd_front.o
+
+obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
new file mode 100644
index 000000000000..f406a8f52c51
--- /dev/null
+++ b/sound/xen/xen_snd_front.c
@@ -0,0 +1,196 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+
+/*
+ * Xen para-virtual sound device
+ *
+ * Copyright (C) 2016-2018 EPAM Systems Inc.
+ *
+ * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
+ */
+
+#include <linux/delay.h>
+#include <linux/module.h>
+
+#include <xen/platform_pci.h>
+#include <xen/xen.h>
+#include <xen/xenbus.h>
+
+#include <xen/interface/io/sndif.h>
+
+#include "xen_snd_front.h"
+
+static void xen_snd_drv_fini(struct xen_snd_front_info *front_info)
+{
+}
+
+static int sndback_initwait(struct xen_snd_front_info *front_info)
+{
+ return 0;
+}
+
+static int sndback_connect(struct xen_snd_front_info *front_info)
+{
+ return 0;
+}
+
+static void sndback_disconnect(struct xen_snd_front_info *front_info)
+{
+ xen_snd_drv_fini(front_info);
+ xenbus_switch_state(front_info->xb_dev, XenbusStateInitialising);
+}
+
+static void sndback_changed(struct xenbus_device *xb_dev,
+ enum xenbus_state backend_state)
+{
+ struct xen_snd_front_info *front_info = dev_get_drvdata(&xb_dev->dev);
+ int ret;
+
+ dev_dbg(&xb_dev->dev, "Backend state is %s, front is %s\n",
+ xenbus_strstate(backend_state),
+ xenbus_strstate(xb_dev->state));
+
+ switch (backend_state) {
+ case XenbusStateReconfiguring:
+ /* fall through */
+ case XenbusStateReconfigured:
+ /* fall through */
+ case XenbusStateInitialised:
+ /* fall through */
+ break;
+
+ case XenbusStateInitialising:
+ /* recovering after backend unexpected closure */
+ sndback_disconnect(front_info);
+ break;
+
+ case XenbusStateInitWait:
+ /* recovering after backend unexpected closure */
+ sndback_disconnect(front_info);
+
+ ret = sndback_initwait(front_info);
+ if (ret < 0)
+ xenbus_dev_fatal(xb_dev, ret, "initializing frontend");
+ else
+ xenbus_switch_state(xb_dev, XenbusStateInitialised);
+ break;
+
+ case XenbusStateConnected:
+ if (xb_dev->state != XenbusStateInitialised)
+ break;
+
+ ret = sndback_connect(front_info);
+ if (ret < 0)
+ xenbus_dev_fatal(xb_dev, ret, "initializing frontend");
+ else
+ xenbus_switch_state(xb_dev, XenbusStateConnected);
+ break;
+
+ case XenbusStateClosing:
+ /*
+ * in this state backend starts freeing resources,
+ * so let it go into closed state first, so we can also
+ * remove ours
+ */
+ break;
+
+ case XenbusStateUnknown:
+ /* fall through */
+ case XenbusStateClosed:
+ if (xb_dev->state == XenbusStateClosed)
+ break;
+
+ sndback_disconnect(front_info);
+ break;
+ }
+}
+
+static int xen_drv_probe(struct xenbus_device *xb_dev,
+ const struct xenbus_device_id *id)
+{
+ struct xen_snd_front_info *front_info;
+
+ front_info = devm_kzalloc(&xb_dev->dev,
+ sizeof(*front_info), GFP_KERNEL);
+ if (!front_info)
+ return -ENOMEM;
+
+ front_info->xb_dev = xb_dev;
+ dev_set_drvdata(&xb_dev->dev, front_info);
+
+ return xenbus_switch_state(xb_dev, XenbusStateInitialising);
+}
+
+static int xen_drv_remove(struct xenbus_device *dev)
+{
+ struct xen_snd_front_info *front_info = dev_get_drvdata(&dev->dev);
+ int to = 100;
+
+ xenbus_switch_state(dev, XenbusStateClosing);
+
+ /*
+ * On driver removal it is disconnected from XenBus,
+ * so no backend state change events come via .otherend_changed
+ * callback. This prevents us from exiting gracefully, e.g.
+ * signaling the backend to free event channels, waiting for its
+ * state to change to XenbusStateClosed and cleaning at our end.
+ * Normally when front driver removed backend will finally go into
+ * XenbusStateInitWait state.
+ *
+ * Workaround: read backend's state manually and wait with time-out.
+ */
+ while ((xenbus_read_unsigned(front_info->xb_dev->otherend, "state",
+ XenbusStateUnknown) != XenbusStateInitWait) &&
+ to--)
+ msleep(10);
+
+ if (!to) {
+ unsigned int state;
+
+ state = xenbus_read_unsigned(front_info->xb_dev->otherend,
+ "state", XenbusStateUnknown);
+ pr_err("Backend state is %s while removing driver\n",
+ xenbus_strstate(state));
+ }
+
+ xen_snd_drv_fini(front_info);
+ xenbus_frontend_closed(dev);
+ return 0;
+}
+
+static const struct xenbus_device_id xen_drv_ids[] = {
+ { XENSND_DRIVER_NAME },
+ { "" }
+};
+
+static struct xenbus_driver xen_driver = {
+ .ids = xen_drv_ids,
+ .probe = xen_drv_probe,
+ .remove = xen_drv_remove,
+ .otherend_changed = sndback_changed,
+};
+
+static int __init xen_drv_init(void)
+{
+ if (!xen_domain())
+ return -ENODEV;
+
+ if (!xen_has_pv_devices())
+ return -ENODEV;
+
+ pr_info("Initialising Xen " XENSND_DRIVER_NAME " frontend driver\n");
+ return xenbus_register_frontend(&xen_driver);
+}
+
+static void __exit xen_drv_fini(void)
+{
+ pr_info("Unregistering Xen " XENSND_DRIVER_NAME " frontend driver\n");
+ xenbus_unregister_driver(&xen_driver);
+}
+
+module_init(xen_drv_init);
+module_exit(xen_drv_fini);
+
+MODULE_DESCRIPTION("Xen virtual sound device frontend");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("xen:" XENSND_DRIVER_NAME);
+MODULE_SUPPORTED_DEVICE("{{ALSA,Virtual soundcard}}");
diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
new file mode 100644
index 000000000000..4ae204b23d32
--- /dev/null
+++ b/sound/xen/xen_snd_front.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 OR MIT */
+
+/*
+ * Xen para-virtual sound device
+ *
+ * Copyright (C) 2016-2018 EPAM Systems Inc.
+ *
+ * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
+ */
+
+#ifndef __XEN_SND_FRONT_H
+#define __XEN_SND_FRONT_H
+
+struct xen_snd_front_info {
+ struct xenbus_device *xb_dev;
+};
+
+#endif /* __XEN_SND_FRONT_H */
--
2.16.2
^ permalink raw reply related [flat|nested] 40+ messages in thread
* [PATCH v2 2/5] ALSA: xen-front: Read sound driver configuration from Xen store
2018-04-16 6:24 [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver Oleksandr Andrushchenko
2018-04-16 6:24 ` [PATCH v2 1/5] ALSA: xen-front: Introduce Xen para-virtualized sound " Oleksandr Andrushchenko
@ 2018-04-16 6:24 ` Oleksandr Andrushchenko
2018-04-16 12:55 ` Juergen Gross
2018-04-16 6:24 ` [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling Oleksandr Andrushchenko
` (5 subsequent siblings)
7 siblings, 1 reply; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-16 6:24 UTC (permalink / raw)
To: xen-devel, linux-kernel, alsa-devel, jgross, boris.ostrovsky,
konrad.wilk, perex, tiwai
Cc: andr2000, Oleksandr Andrushchenko
From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Read configuration values from Xen store according
to xen/interface/io/sndif.h protocol:
- introduce configuration structures for different
components, e.g. sound card, device, stream
- read PCM HW parameters, e.g rate, format etc.
- detect stream type (capture/playback)
- read device and card parameters
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
---
sound/xen/Makefile | 3 +-
sound/xen/xen_snd_front.c | 7 +
sound/xen/xen_snd_front.h | 4 +
sound/xen/xen_snd_front_cfg.c | 517 ++++++++++++++++++++++++++++++++++++++++++
sound/xen/xen_snd_front_cfg.h | 46 ++++
5 files changed, 576 insertions(+), 1 deletion(-)
create mode 100644 sound/xen/xen_snd_front_cfg.c
create mode 100644 sound/xen/xen_snd_front_cfg.h
diff --git a/sound/xen/Makefile b/sound/xen/Makefile
index 4507ef3c27fd..06705bef61fa 100644
--- a/sound/xen/Makefile
+++ b/sound/xen/Makefile
@@ -1,5 +1,6 @@
# SPDX-License-Identifier: GPL-2.0 OR MIT
-snd_xen_front-objs := xen_snd_front.o
+snd_xen_front-objs := xen_snd_front.o \
+ xen_snd_front_cfg.o
obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
index f406a8f52c51..65d2494a9d14 100644
--- a/sound/xen/xen_snd_front.c
+++ b/sound/xen/xen_snd_front.c
@@ -25,6 +25,13 @@ static void xen_snd_drv_fini(struct xen_snd_front_info *front_info)
static int sndback_initwait(struct xen_snd_front_info *front_info)
{
+ int num_streams;
+ int ret;
+
+ ret = xen_snd_front_cfg_card(front_info, &num_streams);
+ if (ret < 0)
+ return ret;
+
return 0;
}
diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
index 4ae204b23d32..b52226cb30bc 100644
--- a/sound/xen/xen_snd_front.h
+++ b/sound/xen/xen_snd_front.h
@@ -11,8 +11,12 @@
#ifndef __XEN_SND_FRONT_H
#define __XEN_SND_FRONT_H
+#include "xen_snd_front_cfg.h"
+
struct xen_snd_front_info {
struct xenbus_device *xb_dev;
+
+ struct xen_front_cfg_card cfg;
};
#endif /* __XEN_SND_FRONT_H */
diff --git a/sound/xen/xen_snd_front_cfg.c b/sound/xen/xen_snd_front_cfg.c
new file mode 100644
index 000000000000..d461985afffa
--- /dev/null
+++ b/sound/xen/xen_snd_front_cfg.c
@@ -0,0 +1,517 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+
+/*
+ * Xen para-virtual sound device
+ *
+ * Copyright (C) 2016-2018 EPAM Systems Inc.
+ *
+ * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
+ */
+
+#include <xen/xenbus.h>
+
+#include <xen/interface/io/sndif.h>
+
+#include "xen_snd_front.h"
+#include "xen_snd_front_cfg.h"
+
+/* maximum number of supported streams */
+#define VSND_MAX_STREAM 8
+
+struct cfg_hw_sample_rate {
+ const char *name;
+ unsigned int mask;
+ unsigned int value;
+};
+
+static const struct cfg_hw_sample_rate CFG_HW_SUPPORTED_RATES[] = {
+ { .name = "5512", .mask = SNDRV_PCM_RATE_5512, .value = 5512 },
+ { .name = "8000", .mask = SNDRV_PCM_RATE_8000, .value = 8000 },
+ { .name = "11025", .mask = SNDRV_PCM_RATE_11025, .value = 11025 },
+ { .name = "16000", .mask = SNDRV_PCM_RATE_16000, .value = 16000 },
+ { .name = "22050", .mask = SNDRV_PCM_RATE_22050, .value = 22050 },
+ { .name = "32000", .mask = SNDRV_PCM_RATE_32000, .value = 32000 },
+ { .name = "44100", .mask = SNDRV_PCM_RATE_44100, .value = 44100 },
+ { .name = "48000", .mask = SNDRV_PCM_RATE_48000, .value = 48000 },
+ { .name = "64000", .mask = SNDRV_PCM_RATE_64000, .value = 64000 },
+ { .name = "96000", .mask = SNDRV_PCM_RATE_96000, .value = 96000 },
+ { .name = "176400", .mask = SNDRV_PCM_RATE_176400, .value = 176400 },
+ { .name = "192000", .mask = SNDRV_PCM_RATE_192000, .value = 192000 },
+};
+
+struct cfg_hw_sample_format {
+ const char *name;
+ u64 mask;
+};
+
+static const struct cfg_hw_sample_format CFG_HW_SUPPORTED_FORMATS[] = {
+ {
+ .name = XENSND_PCM_FORMAT_U8_STR,
+ .mask = SNDRV_PCM_FMTBIT_U8
+ },
+ {
+ .name = XENSND_PCM_FORMAT_S8_STR,
+ .mask = SNDRV_PCM_FMTBIT_S8
+ },
+ {
+ .name = XENSND_PCM_FORMAT_U16_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_U16_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_U16_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_U16_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_S16_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_S16_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_S16_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_S16_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_U24_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_U24_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_U24_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_U24_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_S24_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_S24_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_S24_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_S24_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_U32_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_U32_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_U32_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_U32_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_S32_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_S32_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_S32_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_S32_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_A_LAW_STR,
+ .mask = SNDRV_PCM_FMTBIT_A_LAW
+ },
+ {
+ .name = XENSND_PCM_FORMAT_MU_LAW_STR,
+ .mask = SNDRV_PCM_FMTBIT_MU_LAW
+ },
+ {
+ .name = XENSND_PCM_FORMAT_F32_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_FLOAT_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_F32_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_FLOAT_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_F64_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_FLOAT64_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_F64_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_FLOAT64_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE_STR,
+ .mask = SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE_STR,
+ .mask = SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_BE
+ },
+ {
+ .name = XENSND_PCM_FORMAT_IMA_ADPCM_STR,
+ .mask = SNDRV_PCM_FMTBIT_IMA_ADPCM
+ },
+ {
+ .name = XENSND_PCM_FORMAT_MPEG_STR,
+ .mask = SNDRV_PCM_FMTBIT_MPEG
+ },
+ {
+ .name = XENSND_PCM_FORMAT_GSM_STR,
+ .mask = SNDRV_PCM_FMTBIT_GSM
+ },
+};
+
+static void cfg_hw_rates(char *list, unsigned int len,
+ const char *path, struct snd_pcm_hardware *pcm_hw)
+{
+ char *cur_rate;
+ unsigned int cur_mask;
+ unsigned int cur_value;
+ unsigned int rates;
+ unsigned int rate_min;
+ unsigned int rate_max;
+ int i;
+
+ rates = 0;
+ rate_min = -1;
+ rate_max = 0;
+ while ((cur_rate = strsep(&list, XENSND_LIST_SEPARATOR))) {
+ for (i = 0; i < ARRAY_SIZE(CFG_HW_SUPPORTED_RATES); i++)
+ if (!strncasecmp(cur_rate,
+ CFG_HW_SUPPORTED_RATES[i].name,
+ XENSND_SAMPLE_RATE_MAX_LEN)) {
+ cur_mask = CFG_HW_SUPPORTED_RATES[i].mask;
+ cur_value = CFG_HW_SUPPORTED_RATES[i].value;
+ rates |= cur_mask;
+ if (rate_min > cur_value)
+ rate_min = cur_value;
+ if (rate_max < cur_value)
+ rate_max = cur_value;
+ }
+ }
+
+ if (rates) {
+ pcm_hw->rates = rates;
+ pcm_hw->rate_min = rate_min;
+ pcm_hw->rate_max = rate_max;
+ }
+}
+
+static void cfg_formats(char *list, unsigned int len,
+ const char *path, struct snd_pcm_hardware *pcm_hw)
+{
+ u64 formats;
+ char *cur_format;
+ int i;
+
+ formats = 0;
+ while ((cur_format = strsep(&list, XENSND_LIST_SEPARATOR))) {
+ for (i = 0; i < ARRAY_SIZE(CFG_HW_SUPPORTED_FORMATS); i++)
+ if (!strncasecmp(cur_format,
+ CFG_HW_SUPPORTED_FORMATS[i].name,
+ XENSND_SAMPLE_FORMAT_MAX_LEN))
+ formats |= CFG_HW_SUPPORTED_FORMATS[i].mask;
+ }
+
+ if (formats)
+ pcm_hw->formats = formats;
+}
+
+#define MAX_BUFFER_SIZE (64 * 1024)
+#define MIN_PERIOD_SIZE 64
+#define MAX_PERIOD_SIZE MAX_BUFFER_SIZE
+#define USE_FORMATS (SNDRV_PCM_FMTBIT_U8 | \
+ SNDRV_PCM_FMTBIT_S16_LE)
+#define USE_RATE (SNDRV_PCM_RATE_CONTINUOUS | \
+ SNDRV_PCM_RATE_8000_48000)
+#define USE_RATE_MIN 5512
+#define USE_RATE_MAX 48000
+#define USE_CHANNELS_MIN 1
+#define USE_CHANNELS_MAX 2
+#define USE_PERIODS_MIN 2
+#define USE_PERIODS_MAX (MAX_BUFFER_SIZE / MIN_PERIOD_SIZE)
+
+static const struct snd_pcm_hardware SND_DRV_PCM_HW_DEFAULT = {
+ .info = (SNDRV_PCM_INFO_MMAP |
+ SNDRV_PCM_INFO_INTERLEAVED |
+ SNDRV_PCM_INFO_RESUME |
+ SNDRV_PCM_INFO_MMAP_VALID),
+ .formats = USE_FORMATS,
+ .rates = USE_RATE,
+ .rate_min = USE_RATE_MIN,
+ .rate_max = USE_RATE_MAX,
+ .channels_min = USE_CHANNELS_MIN,
+ .channels_max = USE_CHANNELS_MAX,
+ .buffer_bytes_max = MAX_BUFFER_SIZE,
+ .period_bytes_min = MIN_PERIOD_SIZE,
+ .period_bytes_max = MAX_PERIOD_SIZE,
+ .periods_min = USE_PERIODS_MIN,
+ .periods_max = USE_PERIODS_MAX,
+ .fifo_size = 0,
+};
+
+static void cfg_read_pcm_hw(const char *path,
+ struct snd_pcm_hardware *parent_pcm_hw,
+ struct snd_pcm_hardware *pcm_hw)
+{
+ char *list;
+ int val;
+ size_t buf_sz;
+ unsigned int len;
+
+ /* inherit parent's PCM HW and read overrides from XenStore */
+ if (parent_pcm_hw)
+ *pcm_hw = *parent_pcm_hw;
+ else
+ *pcm_hw = SND_DRV_PCM_HW_DEFAULT;
+
+ val = xenbus_read_unsigned(path, XENSND_FIELD_CHANNELS_MIN, 0);
+ if (val)
+ pcm_hw->channels_min = val;
+
+ val = xenbus_read_unsigned(path, XENSND_FIELD_CHANNELS_MAX, 0);
+ if (val)
+ pcm_hw->channels_max = val;
+
+ list = xenbus_read(XBT_NIL, path, XENSND_FIELD_SAMPLE_RATES, &len);
+ if (!IS_ERR(list)) {
+ cfg_hw_rates(list, len, path, pcm_hw);
+ kfree(list);
+ }
+
+ list = xenbus_read(XBT_NIL, path, XENSND_FIELD_SAMPLE_FORMATS, &len);
+ if (!IS_ERR(list)) {
+ cfg_formats(list, len, path, pcm_hw);
+ kfree(list);
+ }
+
+ buf_sz = xenbus_read_unsigned(path, XENSND_FIELD_BUFFER_SIZE, 0);
+ if (buf_sz)
+ pcm_hw->buffer_bytes_max = buf_sz;
+
+ /* update configuration to match new values */
+ if (pcm_hw->channels_min > pcm_hw->channels_max)
+ pcm_hw->channels_min = pcm_hw->channels_max;
+
+ if (pcm_hw->rate_min > pcm_hw->rate_max)
+ pcm_hw->rate_min = pcm_hw->rate_max;
+
+ pcm_hw->period_bytes_max = pcm_hw->buffer_bytes_max;
+
+ pcm_hw->periods_max = pcm_hw->period_bytes_max /
+ pcm_hw->period_bytes_min;
+}
+
+static int cfg_get_stream_type(const char *path, int index,
+ int *num_pb, int *num_cap)
+{
+ char *str = NULL;
+ char *stream_path;
+ int ret;
+
+ *num_pb = 0;
+ *num_cap = 0;
+ stream_path = kasprintf(GFP_KERNEL, "%s/%d", path, index);
+ if (!stream_path) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ str = xenbus_read(XBT_NIL, stream_path, XENSND_FIELD_TYPE, NULL);
+ if (IS_ERR(str)) {
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ if (!strncasecmp(str, XENSND_STREAM_TYPE_PLAYBACK,
+ sizeof(XENSND_STREAM_TYPE_PLAYBACK))) {
+ (*num_pb)++;
+ } else if (!strncasecmp(str, XENSND_STREAM_TYPE_CAPTURE,
+ sizeof(XENSND_STREAM_TYPE_CAPTURE))) {
+ (*num_cap)++;
+ } else {
+ ret = -EINVAL;
+ goto fail;
+ }
+ ret = 0;
+
+fail:
+ kfree(stream_path);
+ kfree(str);
+ return ret;
+}
+
+static int cfg_stream(struct xen_snd_front_info *front_info,
+ struct xen_front_cfg_pcm_instance *pcm_instance,
+ const char *path, int index, int *cur_pb, int *cur_cap,
+ int *stream_cnt)
+{
+ char *str = NULL;
+ char *stream_path;
+ struct xen_front_cfg_stream *stream;
+ int ret;
+
+ stream_path = devm_kasprintf(&front_info->xb_dev->dev,
+ GFP_KERNEL, "%s/%d", path, index);
+ if (!stream_path) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ str = xenbus_read(XBT_NIL, stream_path, XENSND_FIELD_TYPE, NULL);
+ if (IS_ERR(str)) {
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ if (!strncasecmp(str, XENSND_STREAM_TYPE_PLAYBACK,
+ sizeof(XENSND_STREAM_TYPE_PLAYBACK))) {
+ stream = &pcm_instance->streams_pb[(*cur_pb)++];
+ } else if (!strncasecmp(str, XENSND_STREAM_TYPE_CAPTURE,
+ sizeof(XENSND_STREAM_TYPE_CAPTURE))) {
+ stream = &pcm_instance->streams_cap[(*cur_cap)++];
+ } else {
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ /* get next stream index */
+ stream->index = (*stream_cnt)++;
+ stream->xenstore_path = stream_path;
+ /*
+ * check in Xen store if PCM HW configuration exists for this stream
+ * and update if so, e.g. we inherit all values from device's PCM HW,
+ * but can still override some of the values for the stream
+ */
+ cfg_read_pcm_hw(stream->xenstore_path,
+ &pcm_instance->pcm_hw, &stream->pcm_hw);
+ ret = 0;
+
+fail:
+ kfree(str);
+ return ret;
+}
+
+static int cfg_device(struct xen_snd_front_info *front_info,
+ struct xen_front_cfg_pcm_instance *pcm_instance,
+ struct snd_pcm_hardware *parent_pcm_hw,
+ const char *path, int node_index, int *stream_cnt)
+{
+ char *str;
+ char *device_path;
+ int ret, i, num_streams;
+ int num_pb, num_cap;
+ int cur_pb, cur_cap;
+ char node[3];
+
+ device_path = kasprintf(GFP_KERNEL, "%s/%d", path, node_index);
+ if (!device_path)
+ return -ENOMEM;
+
+ str = xenbus_read(XBT_NIL, device_path, XENSND_FIELD_DEVICE_NAME, NULL);
+ if (!IS_ERR(str)) {
+ strncpy(pcm_instance->name, str, sizeof(pcm_instance->name));
+ kfree(str);
+ }
+
+ pcm_instance->device_id = node_index;
+
+ /*
+ * check in Xen store if PCM HW configuration exists for this device
+ * and update if so, e.g. we inherit all values from card's PCM HW,
+ * but can still override some of the values for the device
+ */
+ cfg_read_pcm_hw(device_path, parent_pcm_hw, &pcm_instance->pcm_hw);
+
+ /* find out how many streams were configured in Xen store */
+ num_streams = 0;
+ do {
+ snprintf(node, sizeof(node), "%d", num_streams);
+ if (!xenbus_exists(XBT_NIL, device_path, node))
+ break;
+
+ num_streams++;
+ } while (num_streams < VSND_MAX_STREAM);
+
+ pcm_instance->num_streams_pb = 0;
+ pcm_instance->num_streams_cap = 0;
+ /* get number of playback and capture streams */
+ for (i = 0; i < num_streams; i++) {
+ ret = cfg_get_stream_type(device_path, i, &num_pb, &num_cap);
+ if (ret < 0)
+ goto fail;
+
+ pcm_instance->num_streams_pb += num_pb;
+ pcm_instance->num_streams_cap += num_cap;
+ }
+
+ if (pcm_instance->num_streams_pb) {
+ pcm_instance->streams_pb =
+ devm_kcalloc(&front_info->xb_dev->dev,
+ pcm_instance->num_streams_pb,
+ sizeof(struct xen_front_cfg_stream),
+ GFP_KERNEL);
+ if (!pcm_instance->streams_pb) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+ }
+
+ if (pcm_instance->num_streams_cap) {
+ pcm_instance->streams_cap =
+ devm_kcalloc(&front_info->xb_dev->dev,
+ pcm_instance->num_streams_cap,
+ sizeof(struct xen_front_cfg_stream),
+ GFP_KERNEL);
+ if (!pcm_instance->streams_cap) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+ }
+
+ cur_pb = 0;
+ cur_cap = 0;
+ for (i = 0; i < num_streams; i++) {
+ ret = cfg_stream(front_info, pcm_instance, device_path, i,
+ &cur_pb, &cur_cap, stream_cnt);
+ if (ret < 0)
+ goto fail;
+ }
+ ret = 0;
+
+fail:
+ kfree(device_path);
+ return ret;
+}
+
+int xen_snd_front_cfg_card(struct xen_snd_front_info *front_info,
+ int *stream_cnt)
+{
+ struct xenbus_device *xb_dev = front_info->xb_dev;
+ struct xen_front_cfg_card *cfg = &front_info->cfg;
+ int ret, num_devices, i;
+ char node[3];
+
+ *stream_cnt = 0;
+ num_devices = 0;
+ do {
+ snprintf(node, sizeof(node), "%d", num_devices);
+ if (!xenbus_exists(XBT_NIL, xb_dev->nodename, node))
+ break;
+
+ num_devices++;
+ } while (num_devices < SNDRV_PCM_DEVICES);
+
+ if (!num_devices) {
+ dev_warn(&xb_dev->dev,
+ "No devices configured for sound card at %s\n",
+ xb_dev->nodename);
+ return -ENODEV;
+ }
+
+ /* start from default PCM HW configuration for the card */
+ cfg_read_pcm_hw(xb_dev->nodename, NULL, &cfg->pcm_hw);
+
+ cfg->pcm_instances =
+ devm_kcalloc(&front_info->xb_dev->dev, num_devices,
+ sizeof(struct xen_front_cfg_pcm_instance),
+ GFP_KERNEL);
+ if (!cfg->pcm_instances)
+ return -ENOMEM;
+
+ for (i = 0; i < num_devices; i++) {
+ ret = cfg_device(front_info, &cfg->pcm_instances[i],
+ &cfg->pcm_hw, xb_dev->nodename, i, stream_cnt);
+ if (ret < 0)
+ return ret;
+ }
+ cfg->num_pcm_instances = num_devices;
+ return 0;
+}
+
diff --git a/sound/xen/xen_snd_front_cfg.h b/sound/xen/xen_snd_front_cfg.h
new file mode 100644
index 000000000000..2353fcc74889
--- /dev/null
+++ b/sound/xen/xen_snd_front_cfg.h
@@ -0,0 +1,46 @@
+/* SPDX-License-Identifier: GPL-2.0 OR MIT */
+
+/*
+ * Xen para-virtual sound device
+ *
+ * Copyright (C) 2016-2018 EPAM Systems Inc.
+ *
+ * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
+ */
+
+#ifndef __XEN_SND_FRONT_CFG_H
+#define __XEN_SND_FRONT_CFG_H
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+
+struct xen_snd_front_info;
+
+struct xen_front_cfg_stream {
+ int index;
+ char *xenstore_path;
+ struct snd_pcm_hardware pcm_hw;
+};
+
+struct xen_front_cfg_pcm_instance {
+ char name[80];
+ int device_id;
+ struct snd_pcm_hardware pcm_hw;
+ int num_streams_pb;
+ struct xen_front_cfg_stream *streams_pb;
+ int num_streams_cap;
+ struct xen_front_cfg_stream *streams_cap;
+};
+
+struct xen_front_cfg_card {
+ char name_short[32];
+ char name_long[80];
+ struct snd_pcm_hardware pcm_hw;
+ int num_pcm_instances;
+ struct xen_front_cfg_pcm_instance *pcm_instances;
+};
+
+int xen_snd_front_cfg_card(struct xen_snd_front_info *front_info,
+ int *stream_cnt);
+
+#endif /* __XEN_SND_FRONT_CFG_H */
--
2.16.2
^ permalink raw reply related [flat|nested] 40+ messages in thread
* [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling
2018-04-16 6:24 [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver Oleksandr Andrushchenko
2018-04-16 6:24 ` [PATCH v2 1/5] ALSA: xen-front: Introduce Xen para-virtualized sound " Oleksandr Andrushchenko
2018-04-16 6:24 ` [PATCH v2 2/5] ALSA: xen-front: Read sound driver configuration from Xen store Oleksandr Andrushchenko
@ 2018-04-16 6:24 ` Oleksandr Andrushchenko
2018-04-16 13:12 ` Juergen Gross
` (2 more replies)
2018-04-16 6:24 ` [PATCH v2 4/5] ALSA: xen-front: Implement handling of shared buffers Oleksandr Andrushchenko
` (4 subsequent siblings)
7 siblings, 3 replies; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-16 6:24 UTC (permalink / raw)
To: xen-devel, linux-kernel, alsa-devel, jgross, boris.ostrovsky,
konrad.wilk, perex, tiwai
Cc: andr2000, Oleksandr Andrushchenko
From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Handle Xen event channels:
- create for all configured streams and publish
corresponding ring references and event channels in Xen store,
so backend can connect
- implement event channels interrupt handlers
- create and destroy event channels with respect to Xen bus state
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
---
sound/xen/Makefile | 3 +-
sound/xen/xen_snd_front.c | 10 +-
sound/xen/xen_snd_front.h | 7 +
sound/xen/xen_snd_front_evtchnl.c | 474 ++++++++++++++++++++++++++++++++++++++
sound/xen/xen_snd_front_evtchnl.h | 92 ++++++++
5 files changed, 584 insertions(+), 2 deletions(-)
create mode 100644 sound/xen/xen_snd_front_evtchnl.c
create mode 100644 sound/xen/xen_snd_front_evtchnl.h
diff --git a/sound/xen/Makefile b/sound/xen/Makefile
index 06705bef61fa..03c669984000 100644
--- a/sound/xen/Makefile
+++ b/sound/xen/Makefile
@@ -1,6 +1,7 @@
# SPDX-License-Identifier: GPL-2.0 OR MIT
snd_xen_front-objs := xen_snd_front.o \
- xen_snd_front_cfg.o
+ xen_snd_front_cfg.o \
+ xen_snd_front_evtchnl.o
obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
index 65d2494a9d14..eb46bf4070f9 100644
--- a/sound/xen/xen_snd_front.c
+++ b/sound/xen/xen_snd_front.c
@@ -18,9 +18,11 @@
#include <xen/interface/io/sndif.h>
#include "xen_snd_front.h"
+#include "xen_snd_front_evtchnl.h"
static void xen_snd_drv_fini(struct xen_snd_front_info *front_info)
{
+ xen_snd_front_evtchnl_free_all(front_info);
}
static int sndback_initwait(struct xen_snd_front_info *front_info)
@@ -32,7 +34,12 @@ static int sndback_initwait(struct xen_snd_front_info *front_info)
if (ret < 0)
return ret;
- return 0;
+ /* create event channels for all streams and publish */
+ ret = xen_snd_front_evtchnl_create_all(front_info, num_streams);
+ if (ret < 0)
+ return ret;
+
+ return xen_snd_front_evtchnl_publish_all(front_info);
}
static int sndback_connect(struct xen_snd_front_info *front_info)
@@ -122,6 +129,7 @@ static int xen_drv_probe(struct xenbus_device *xb_dev,
return -ENOMEM;
front_info->xb_dev = xb_dev;
+ spin_lock_init(&front_info->io_lock);
dev_set_drvdata(&xb_dev->dev, front_info);
return xenbus_switch_state(xb_dev, XenbusStateInitialising);
diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
index b52226cb30bc..9c2ffbb4e4b8 100644
--- a/sound/xen/xen_snd_front.h
+++ b/sound/xen/xen_snd_front.h
@@ -13,9 +13,16 @@
#include "xen_snd_front_cfg.h"
+struct xen_snd_front_evtchnl_pair;
+
struct xen_snd_front_info {
struct xenbus_device *xb_dev;
+ /* serializer for backend IO: request/response */
+ spinlock_t io_lock;
+ int num_evt_pairs;
+ struct xen_snd_front_evtchnl_pair *evt_pairs;
+
struct xen_front_cfg_card cfg;
};
diff --git a/sound/xen/xen_snd_front_evtchnl.c b/sound/xen/xen_snd_front_evtchnl.c
new file mode 100644
index 000000000000..9ece39f938f8
--- /dev/null
+++ b/sound/xen/xen_snd_front_evtchnl.c
@@ -0,0 +1,474 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+
+/*
+ * Xen para-virtual sound device
+ *
+ * Copyright (C) 2016-2018 EPAM Systems Inc.
+ *
+ * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
+ */
+
+#include <xen/events.h>
+#include <xen/grant_table.h>
+#include <xen/xen.h>
+#include <xen/xenbus.h>
+
+#include "xen_snd_front.h"
+#include "xen_snd_front_cfg.h"
+#include "xen_snd_front_evtchnl.h"
+
+static irqreturn_t evtchnl_interrupt_req(int irq, void *dev_id)
+{
+ struct xen_snd_front_evtchnl *channel = dev_id;
+ struct xen_snd_front_info *front_info = channel->front_info;
+ struct xensnd_resp *resp;
+ RING_IDX i, rp;
+ unsigned long flags;
+
+ if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
+ return IRQ_HANDLED;
+
+ spin_lock_irqsave(&front_info->io_lock, flags);
+
+again:
+ rp = channel->u.req.ring.sring->rsp_prod;
+ /* ensure we see queued responses up to rp */
+ rmb();
+
+ for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
+ resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
+ if (resp->id != channel->evt_id)
+ continue;
+ switch (resp->operation) {
+ case XENSND_OP_OPEN:
+ /* fall through */
+ case XENSND_OP_CLOSE:
+ /* fall through */
+ case XENSND_OP_READ:
+ /* fall through */
+ case XENSND_OP_WRITE:
+ /* fall through */
+ case XENSND_OP_TRIGGER:
+ channel->u.req.resp_status = resp->status;
+ complete(&channel->u.req.completion);
+ break;
+ case XENSND_OP_HW_PARAM_QUERY:
+ channel->u.req.resp_status = resp->status;
+ channel->u.req.resp.hw_param =
+ resp->resp.hw_param;
+ complete(&channel->u.req.completion);
+ break;
+
+ default:
+ dev_err(&front_info->xb_dev->dev,
+ "Operation %d is not supported\n",
+ resp->operation);
+ break;
+ }
+ }
+
+ channel->u.req.ring.rsp_cons = i;
+ if (i != channel->u.req.ring.req_prod_pvt) {
+ int more_to_do;
+
+ RING_FINAL_CHECK_FOR_RESPONSES(&channel->u.req.ring,
+ more_to_do);
+ if (more_to_do)
+ goto again;
+ } else {
+ channel->u.req.ring.sring->rsp_event = i + 1;
+ }
+
+ spin_unlock_irqrestore(&front_info->io_lock, flags);
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t evtchnl_interrupt_evt(int irq, void *dev_id)
+{
+ struct xen_snd_front_evtchnl *channel = dev_id;
+ struct xen_snd_front_info *front_info = channel->front_info;
+ struct xensnd_event_page *page = channel->u.evt.page;
+ u32 cons, prod;
+ unsigned long flags;
+
+ if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
+ return IRQ_HANDLED;
+
+ spin_lock_irqsave(&front_info->io_lock, flags);
+
+ prod = page->in_prod;
+ /* ensure we see ring contents up to prod */
+ virt_rmb();
+ if (prod == page->in_cons)
+ goto out;
+
+ for (cons = page->in_cons; cons != prod; cons++) {
+ struct xensnd_evt *event;
+
+ event = &XENSND_IN_RING_REF(page, cons);
+ if (unlikely(event->id != channel->evt_id++))
+ continue;
+
+ switch (event->type) {
+ case XENSND_EVT_CUR_POS:
+ /* do nothing at the moment */
+ break;
+ }
+ }
+
+ page->in_cons = cons;
+ /* ensure ring contents */
+ virt_wmb();
+
+out:
+ spin_unlock_irqrestore(&front_info->io_lock, flags);
+ return IRQ_HANDLED;
+}
+
+void xen_snd_front_evtchnl_flush(struct xen_snd_front_evtchnl *channel)
+{
+ int notify;
+
+ channel->u.req.ring.req_prod_pvt++;
+ RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&channel->u.req.ring, notify);
+ if (notify)
+ notify_remote_via_irq(channel->irq);
+}
+
+static void evtchnl_free(struct xen_snd_front_info *front_info,
+ struct xen_snd_front_evtchnl *channel)
+{
+ unsigned long page = 0;
+
+ if (channel->type == EVTCHNL_TYPE_REQ)
+ page = (unsigned long)channel->u.req.ring.sring;
+ else if (channel->type == EVTCHNL_TYPE_EVT)
+ page = (unsigned long)channel->u.evt.page;
+
+ if (!page)
+ return;
+
+ channel->state = EVTCHNL_STATE_DISCONNECTED;
+ if (channel->type == EVTCHNL_TYPE_REQ) {
+ /* release all who still waits for response if any */
+ channel->u.req.resp_status = -EIO;
+ complete_all(&channel->u.req.completion);
+ }
+
+ if (channel->irq)
+ unbind_from_irqhandler(channel->irq, channel);
+
+ if (channel->port)
+ xenbus_free_evtchn(front_info->xb_dev, channel->port);
+
+ /* end access and free the page */
+ if (channel->gref != GRANT_INVALID_REF)
+ gnttab_end_foreign_access(channel->gref, 0, page);
+
+ memset(channel, 0, sizeof(*channel));
+}
+
+void xen_snd_front_evtchnl_free_all(struct xen_snd_front_info *front_info)
+{
+ int i;
+
+ if (!front_info->evt_pairs)
+ return;
+
+ for (i = 0; i < front_info->num_evt_pairs; i++) {
+ evtchnl_free(front_info, &front_info->evt_pairs[i].req);
+ evtchnl_free(front_info, &front_info->evt_pairs[i].evt);
+ }
+
+ kfree(front_info->evt_pairs);
+ front_info->evt_pairs = NULL;
+}
+
+static int evtchnl_alloc(struct xen_snd_front_info *front_info, int index,
+ struct xen_snd_front_evtchnl *channel,
+ enum xen_snd_front_evtchnl_type type)
+{
+ struct xenbus_device *xb_dev = front_info->xb_dev;
+ unsigned long page;
+ grant_ref_t gref;
+ irq_handler_t handler;
+ char *handler_name = NULL;
+ int ret;
+
+ memset(channel, 0, sizeof(*channel));
+ channel->type = type;
+ channel->index = index;
+ channel->front_info = front_info;
+ channel->state = EVTCHNL_STATE_DISCONNECTED;
+ channel->gref = GRANT_INVALID_REF;
+ page = get_zeroed_page(GFP_NOIO | __GFP_HIGH);
+ if (!page) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ handler_name = kasprintf(GFP_KERNEL, "%s-%s", XENSND_DRIVER_NAME,
+ type == EVTCHNL_TYPE_REQ ?
+ XENSND_FIELD_RING_REF :
+ XENSND_FIELD_EVT_RING_REF);
+ if (!handler_name) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ if (type == EVTCHNL_TYPE_REQ) {
+ struct xen_sndif_sring *sring = (struct xen_sndif_sring *)page;
+
+ init_completion(&channel->u.req.completion);
+ mutex_init(&channel->u.req.req_io_lock);
+ SHARED_RING_INIT(sring);
+ FRONT_RING_INIT(&channel->u.req.ring, sring, XEN_PAGE_SIZE);
+
+ ret = xenbus_grant_ring(xb_dev, sring, 1, &gref);
+ if (ret < 0) {
+ channel->u.req.ring.sring = NULL;
+ free_page(page);
+ goto fail;
+ }
+
+ handler = evtchnl_interrupt_req;
+ } else {
+ ret = gnttab_grant_foreign_access(xb_dev->otherend_id,
+ virt_to_gfn((void *)page), 0);
+ if (ret < 0) {
+ free_page(page);
+ goto fail;
+ }
+
+ channel->u.evt.page = (struct xensnd_event_page *)page;
+ gref = ret;
+ handler = evtchnl_interrupt_evt;
+ }
+
+ channel->gref = gref;
+
+ ret = xenbus_alloc_evtchn(xb_dev, &channel->port);
+ if (ret < 0)
+ goto fail;
+
+ ret = bind_evtchn_to_irq(channel->port);
+ if (ret < 0) {
+ dev_err(&xb_dev->dev,
+ "Failed to bind IRQ for domid %d port %d: %d\n",
+ front_info->xb_dev->otherend_id, channel->port, ret);
+ goto fail;
+ }
+
+ channel->irq = ret;
+
+ ret = request_threaded_irq(channel->irq, NULL, handler,
+ IRQF_ONESHOT, handler_name, channel);
+ if (ret < 0) {
+ dev_err(&xb_dev->dev, "Failed to request IRQ %d: %d\n",
+ channel->irq, ret);
+ goto fail;
+ }
+
+ kfree(handler_name);
+ return 0;
+
+fail:
+ kfree(handler_name);
+ dev_err(&xb_dev->dev, "Failed to allocate ring: %d\n", ret);
+ return ret;
+}
+
+int xen_snd_front_evtchnl_create_all(struct xen_snd_front_info *front_info,
+ int num_streams)
+{
+ struct xen_front_cfg_card *cfg = &front_info->cfg;
+ struct device *dev = &front_info->xb_dev->dev;
+ int d, ret = 0;
+
+ front_info->evt_pairs =
+ kcalloc(num_streams,
+ sizeof(struct xen_snd_front_evtchnl_pair),
+ GFP_KERNEL);
+ if (!front_info->evt_pairs)
+ return -ENOMEM;
+
+ /* iterate over devices and their streams and create event channels */
+ for (d = 0; d < cfg->num_pcm_instances; d++) {
+ struct xen_front_cfg_pcm_instance *pcm_instance;
+ int s, index;
+
+ pcm_instance = &cfg->pcm_instances[d];
+
+ for (s = 0; s < pcm_instance->num_streams_pb; s++) {
+ index = pcm_instance->streams_pb[s].index;
+
+ ret = evtchnl_alloc(front_info, index,
+ &front_info->evt_pairs[index].req,
+ EVTCHNL_TYPE_REQ);
+ if (ret < 0) {
+ dev_err(dev, "Error allocating control channel\n");
+ goto fail;
+ }
+
+ ret = evtchnl_alloc(front_info, index,
+ &front_info->evt_pairs[index].evt,
+ EVTCHNL_TYPE_EVT);
+ if (ret < 0) {
+ dev_err(dev, "Error allocating in-event channel\n");
+ goto fail;
+ }
+ }
+
+ for (s = 0; s < pcm_instance->num_streams_cap; s++) {
+ index = pcm_instance->streams_cap[s].index;
+
+ ret = evtchnl_alloc(front_info, index,
+ &front_info->evt_pairs[index].req,
+ EVTCHNL_TYPE_REQ);
+ if (ret < 0) {
+ dev_err(dev, "Error allocating control channel\n");
+ goto fail;
+ }
+
+ ret = evtchnl_alloc(front_info, index,
+ &front_info->evt_pairs[index].evt,
+ EVTCHNL_TYPE_EVT);
+ if (ret < 0) {
+ dev_err(dev, "Error allocating in-event channel\n");
+ goto fail;
+ }
+ }
+ }
+ if (ret < 0)
+ goto fail;
+
+ front_info->num_evt_pairs = num_streams;
+ return 0;
+
+fail:
+ xen_snd_front_evtchnl_free_all(front_info);
+ return ret;
+}
+
+static int evtchnl_publish(struct xenbus_transaction xbt,
+ struct xen_snd_front_evtchnl *channel,
+ const char *path, const char *node_ring,
+ const char *node_chnl)
+{
+ struct xenbus_device *xb_dev = channel->front_info->xb_dev;
+ int ret;
+
+ /* write control channel ring reference */
+ ret = xenbus_printf(xbt, path, node_ring, "%u", channel->gref);
+ if (ret < 0) {
+ dev_err(&xb_dev->dev, "Error writing ring-ref: %d\n", ret);
+ return ret;
+ }
+
+ /* write event channel ring reference */
+ ret = xenbus_printf(xbt, path, node_chnl, "%u", channel->port);
+ if (ret < 0) {
+ dev_err(&xb_dev->dev, "Error writing event channel: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+int xen_snd_front_evtchnl_publish_all(struct xen_snd_front_info *front_info)
+{
+ struct xen_front_cfg_card *cfg = &front_info->cfg;
+ struct xenbus_transaction xbt;
+ int ret, d;
+
+again:
+ ret = xenbus_transaction_start(&xbt);
+ if (ret < 0) {
+ xenbus_dev_fatal(front_info->xb_dev, ret,
+ "starting transaction");
+ return ret;
+ }
+
+ for (d = 0; d < cfg->num_pcm_instances; d++) {
+ struct xen_front_cfg_pcm_instance *pcm_instance;
+ int s, index;
+
+ pcm_instance = &cfg->pcm_instances[d];
+
+ for (s = 0; s < pcm_instance->num_streams_pb; s++) {
+ index = pcm_instance->streams_pb[s].index;
+
+ ret = evtchnl_publish(xbt,
+ &front_info->evt_pairs[index].req,
+ pcm_instance->streams_pb[s].xenstore_path,
+ XENSND_FIELD_RING_REF,
+ XENSND_FIELD_EVT_CHNL);
+ if (ret < 0)
+ goto fail;
+
+ ret = evtchnl_publish(xbt,
+ &front_info->evt_pairs[index].evt,
+ pcm_instance->streams_pb[s].xenstore_path,
+ XENSND_FIELD_EVT_RING_REF,
+ XENSND_FIELD_EVT_EVT_CHNL);
+ if (ret < 0)
+ goto fail;
+ }
+
+ for (s = 0; s < pcm_instance->num_streams_cap; s++) {
+ index = pcm_instance->streams_cap[s].index;
+
+ ret = evtchnl_publish(xbt,
+ &front_info->evt_pairs[index].req,
+ pcm_instance->streams_cap[s].xenstore_path,
+ XENSND_FIELD_RING_REF,
+ XENSND_FIELD_EVT_CHNL);
+ if (ret < 0)
+ goto fail;
+
+ ret = evtchnl_publish(xbt,
+ &front_info->evt_pairs[index].evt,
+ pcm_instance->streams_cap[s].xenstore_path,
+ XENSND_FIELD_EVT_RING_REF,
+ XENSND_FIELD_EVT_EVT_CHNL);
+ if (ret < 0)
+ goto fail;
+ }
+ }
+ ret = xenbus_transaction_end(xbt, 0);
+ if (ret < 0) {
+ if (ret == -EAGAIN)
+ goto again;
+
+ xenbus_dev_fatal(front_info->xb_dev, ret,
+ "completing transaction");
+ goto fail_to_end;
+ }
+ return 0;
+fail:
+ xenbus_transaction_end(xbt, 1);
+fail_to_end:
+ xenbus_dev_fatal(front_info->xb_dev, ret, "writing XenStore");
+ return ret;
+}
+
+void xen_snd_front_evtchnl_pair_set_connected(struct xen_snd_front_evtchnl_pair *evt_pair,
+ bool is_connected)
+{
+ enum xen_snd_front_evtchnl_state state;
+
+ if (is_connected)
+ state = EVTCHNL_STATE_CONNECTED;
+ else
+ state = EVTCHNL_STATE_DISCONNECTED;
+
+ evt_pair->req.state = state;
+ evt_pair->evt.state = state;
+}
+
+void xen_snd_front_evtchnl_pair_clear(struct xen_snd_front_evtchnl_pair *evt_pair)
+{
+ evt_pair->req.evt_next_id = 0;
+ evt_pair->evt.evt_next_id = 0;
+}
+
diff --git a/sound/xen/xen_snd_front_evtchnl.h b/sound/xen/xen_snd_front_evtchnl.h
new file mode 100644
index 000000000000..c4921f469347
--- /dev/null
+++ b/sound/xen/xen_snd_front_evtchnl.h
@@ -0,0 +1,92 @@
+/* SPDX-License-Identifier: GPL-2.0 OR MIT */
+
+/*
+ * Xen para-virtual sound device
+ *
+ * Copyright (C) 2016-2018 EPAM Systems Inc.
+ *
+ * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
+ */
+
+#ifndef __XEN_SND_FRONT_EVTCHNL_H
+#define __XEN_SND_FRONT_EVTCHNL_H
+
+#include <xen/interface/io/sndif.h>
+
+struct xen_snd_front_info;
+
+#ifndef GRANT_INVALID_REF
+/*
+ * FIXME: usage of grant reference 0 as invalid grant reference:
+ * grant reference 0 is valid, but never exposed to a PV driver,
+ * because of the fact it is already in use/reserved by the PV console.
+ */
+#define GRANT_INVALID_REF 0
+#endif
+
+/* timeout in ms to wait for backend to respond */
+#define VSND_WAIT_BACK_MS 3000
+
+enum xen_snd_front_evtchnl_state {
+ EVTCHNL_STATE_DISCONNECTED,
+ EVTCHNL_STATE_CONNECTED,
+};
+
+enum xen_snd_front_evtchnl_type {
+ EVTCHNL_TYPE_REQ,
+ EVTCHNL_TYPE_EVT,
+};
+
+struct xen_snd_front_evtchnl {
+ struct xen_snd_front_info *front_info;
+ int gref;
+ int port;
+ int irq;
+ int index;
+ /* state of the event channel */
+ enum xen_snd_front_evtchnl_state state;
+ enum xen_snd_front_evtchnl_type type;
+ /* either response id or incoming event id */
+ u16 evt_id;
+ /* next request id or next expected event id */
+ u16 evt_next_id;
+ union {
+ struct {
+ struct xen_sndif_front_ring ring;
+ struct completion completion;
+ /* latest response status */
+ int resp_status;
+ /* serializer for backend IO: request/response */
+ struct mutex req_io_lock;
+ union {
+ struct xensnd_query_hw_param hw_param;
+ } resp;
+ } req;
+ struct {
+ struct xensnd_event_page *page;
+ /* this is needed to handle XENSND_EVT_CUR_POS event */
+ struct snd_pcm_substream *substream;
+ } evt;
+ } u;
+};
+
+struct xen_snd_front_evtchnl_pair {
+ struct xen_snd_front_evtchnl req;
+ struct xen_snd_front_evtchnl evt;
+};
+
+int xen_snd_front_evtchnl_create_all(struct xen_snd_front_info *front_info,
+ int num_streams);
+
+void xen_snd_front_evtchnl_free_all(struct xen_snd_front_info *front_info);
+
+int xen_snd_front_evtchnl_publish_all(struct xen_snd_front_info *front_info);
+
+void xen_snd_front_evtchnl_flush(struct xen_snd_front_evtchnl *evtchnl);
+
+void xen_snd_front_evtchnl_pair_set_connected(struct xen_snd_front_evtchnl_pair *evt_pair,
+ bool is_connected);
+
+void xen_snd_front_evtchnl_pair_clear(struct xen_snd_front_evtchnl_pair *evt_pair);
+
+#endif /* __XEN_SND_FRONT_EVTCHNL_H */
--
2.16.2
^ permalink raw reply related [flat|nested] 40+ messages in thread
* [PATCH v2 4/5] ALSA: xen-front: Implement handling of shared buffers
2018-04-16 6:24 [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver Oleksandr Andrushchenko
` (2 preceding siblings ...)
2018-04-16 6:24 ` [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling Oleksandr Andrushchenko
@ 2018-04-16 6:24 ` Oleksandr Andrushchenko
2018-04-16 13:39 ` Juergen Gross
2018-04-16 6:24 ` [PATCH v2 5/5] ALSA: xen-front: Implement ALSA virtual sound driver Oleksandr Andrushchenko
` (3 subsequent siblings)
7 siblings, 1 reply; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-16 6:24 UTC (permalink / raw)
To: xen-devel, linux-kernel, alsa-devel, jgross, boris.ostrovsky,
konrad.wilk, perex, tiwai
Cc: andr2000, Oleksandr Andrushchenko
From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Implement shared buffer handling according to the
para-virtualized sound device protocol at xen/interface/io/sndif.h:
- manage buffer memory
- handle granted references
- handle page directories
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
---
sound/xen/Makefile | 3 +-
sound/xen/xen_snd_front.c | 8 ++
sound/xen/xen_snd_front_shbuf.c | 193 ++++++++++++++++++++++++++++++++++++++++
sound/xen/xen_snd_front_shbuf.h | 36 ++++++++
4 files changed, 239 insertions(+), 1 deletion(-)
create mode 100644 sound/xen/xen_snd_front_shbuf.c
create mode 100644 sound/xen/xen_snd_front_shbuf.h
diff --git a/sound/xen/Makefile b/sound/xen/Makefile
index 03c669984000..f028bc30af5d 100644
--- a/sound/xen/Makefile
+++ b/sound/xen/Makefile
@@ -2,6 +2,7 @@
snd_xen_front-objs := xen_snd_front.o \
xen_snd_front_cfg.o \
- xen_snd_front_evtchnl.o
+ xen_snd_front_evtchnl.o \
+ xen_snd_front_shbuf.o
obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
index eb46bf4070f9..0569c6c596a3 100644
--- a/sound/xen/xen_snd_front.c
+++ b/sound/xen/xen_snd_front.c
@@ -11,6 +11,7 @@
#include <linux/delay.h>
#include <linux/module.h>
+#include <xen/page.h>
#include <xen/platform_pci.h>
#include <xen/xen.h>
#include <xen/xenbus.h>
@@ -186,6 +187,13 @@ static struct xenbus_driver xen_driver = {
static int __init xen_drv_init(void)
{
+ /* At the moment we only support case with XEN_PAGE_SIZE == PAGE_SIZE */
+ if (XEN_PAGE_SIZE != PAGE_SIZE) {
+ pr_err(XENSND_DRIVER_NAME ": different kernel and Xen page sizes are not supported: XEN_PAGE_SIZE (%lu) != PAGE_SIZE (%lu)\n",
+ XEN_PAGE_SIZE, PAGE_SIZE);
+ return -ENODEV;
+ }
+
if (!xen_domain())
return -ENODEV;
diff --git a/sound/xen/xen_snd_front_shbuf.c b/sound/xen/xen_snd_front_shbuf.c
new file mode 100644
index 000000000000..6845dbc7fdf5
--- /dev/null
+++ b/sound/xen/xen_snd_front_shbuf.c
@@ -0,0 +1,193 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+
+/*
+ * Xen para-virtual sound device
+ *
+ * Copyright (C) 2016-2018 EPAM Systems Inc.
+ *
+ * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
+ */
+
+#include <xen/xen.h>
+#include <xen/xenbus.h>
+
+#include "xen_snd_front_shbuf.h"
+
+grant_ref_t xen_snd_front_shbuf_get_dir_start(struct xen_snd_front_shbuf *buf)
+{
+ if (!buf->grefs)
+ return GRANT_INVALID_REF;
+
+ return buf->grefs[0];
+}
+
+void xen_snd_front_shbuf_clear(struct xen_snd_front_shbuf *buf)
+{
+ memset(buf, 0, sizeof(*buf));
+}
+
+void xen_snd_front_shbuf_free(struct xen_snd_front_shbuf *buf)
+{
+ int i;
+
+ if (buf->grefs) {
+ for (i = 0; i < buf->num_grefs; i++)
+ if (buf->grefs[i] != GRANT_INVALID_REF)
+ gnttab_end_foreign_access(buf->grefs[i],
+ 0, 0UL);
+ kfree(buf->grefs);
+ }
+ kfree(buf->directory);
+ free_pages_exact(buf->buffer, buf->buffer_sz);
+ xen_snd_front_shbuf_clear(buf);
+}
+
+/*
+ * number of grant references a page can hold with respect to the
+ * xensnd_page_directory header
+ */
+#define XENSND_NUM_GREFS_PER_PAGE ((XEN_PAGE_SIZE - \
+ offsetof(struct xensnd_page_directory, gref)) / \
+ sizeof(grant_ref_t))
+
+static void fill_page_dir(struct xen_snd_front_shbuf *buf,
+ int num_pages_dir)
+{
+ struct xensnd_page_directory *page_dir;
+ unsigned char *ptr;
+ int i, cur_gref, grefs_left, to_copy;
+
+ ptr = buf->directory;
+ grefs_left = buf->num_grefs - num_pages_dir;
+ /*
+ * skip grant references at the beginning, they are for pages granted
+ * for the page directory itself
+ */
+ cur_gref = num_pages_dir;
+ for (i = 0; i < num_pages_dir; i++) {
+ page_dir = (struct xensnd_page_directory *)ptr;
+ if (grefs_left <= XENSND_NUM_GREFS_PER_PAGE) {
+ to_copy = grefs_left;
+ page_dir->gref_dir_next_page = GRANT_INVALID_REF;
+ } else {
+ to_copy = XENSND_NUM_GREFS_PER_PAGE;
+ page_dir->gref_dir_next_page = buf->grefs[i + 1];
+ }
+
+ memcpy(&page_dir->gref, &buf->grefs[cur_gref],
+ to_copy * sizeof(grant_ref_t));
+
+ ptr += XEN_PAGE_SIZE;
+ grefs_left -= to_copy;
+ cur_gref += to_copy;
+ }
+}
+
+static int grant_references(struct xenbus_device *xb_dev,
+ struct xen_snd_front_shbuf *buf,
+ int num_pages_dir, int num_pages_buffer,
+ int num_grefs)
+{
+ grant_ref_t priv_gref_head;
+ unsigned long frame;
+ int ret, i, j, cur_ref;
+ int otherend_id;
+
+ ret = gnttab_alloc_grant_references(num_grefs, &priv_gref_head);
+ if (ret)
+ return ret;
+
+ buf->num_grefs = num_grefs;
+ otherend_id = xb_dev->otherend_id;
+ j = 0;
+
+ for (i = 0; i < num_pages_dir; i++) {
+ cur_ref = gnttab_claim_grant_reference(&priv_gref_head);
+ if (cur_ref < 0) {
+ ret = cur_ref;
+ goto fail;
+ }
+
+ frame = xen_page_to_gfn(virt_to_page(buf->directory +
+ XEN_PAGE_SIZE * i));
+ gnttab_grant_foreign_access_ref(cur_ref, otherend_id, frame, 0);
+ buf->grefs[j++] = cur_ref;
+ }
+
+ for (i = 0; i < num_pages_buffer; i++) {
+ cur_ref = gnttab_claim_grant_reference(&priv_gref_head);
+ if (cur_ref < 0) {
+ ret = cur_ref;
+ goto fail;
+ }
+
+ frame = xen_page_to_gfn(virt_to_page(buf->buffer +
+ XEN_PAGE_SIZE * i));
+ gnttab_grant_foreign_access_ref(cur_ref, otherend_id, frame, 0);
+ buf->grefs[j++] = cur_ref;
+ }
+
+ gnttab_free_grant_references(priv_gref_head);
+ fill_page_dir(buf, num_pages_dir);
+ return 0;
+
+fail:
+ gnttab_free_grant_references(priv_gref_head);
+ return ret;
+}
+
+static int alloc_int_buffers(struct xen_snd_front_shbuf *buf,
+ int num_pages_dir, int num_pages_buffer,
+ int num_grefs)
+{
+ buf->grefs = kcalloc(num_grefs, sizeof(*buf->grefs), GFP_KERNEL);
+ if (!buf->grefs)
+ return -ENOMEM;
+
+ buf->directory = kcalloc(num_pages_dir, XEN_PAGE_SIZE, GFP_KERNEL);
+ if (!buf->directory)
+ goto fail;
+
+ buf->buffer_sz = num_pages_buffer * XEN_PAGE_SIZE;
+ buf->buffer = alloc_pages_exact(buf->buffer_sz, GFP_KERNEL);
+ if (!buf->buffer)
+ goto fail;
+
+ return 0;
+
+fail:
+ kfree(buf->grefs);
+ buf->grefs = NULL;
+ kfree(buf->directory);
+ buf->directory = NULL;
+ return -ENOMEM;
+}
+
+int xen_snd_front_shbuf_alloc(struct xenbus_device *xb_dev,
+ struct xen_snd_front_shbuf *buf,
+ unsigned int buffer_sz)
+{
+ int num_pages_buffer, num_pages_dir, num_grefs;
+ int ret;
+
+ xen_snd_front_shbuf_clear(buf);
+
+ num_pages_buffer = DIV_ROUND_UP(buffer_sz, XEN_PAGE_SIZE);
+ /* number of pages the page directory consumes itself */
+ num_pages_dir = DIV_ROUND_UP(num_pages_buffer,
+ XENSND_NUM_GREFS_PER_PAGE);
+ num_grefs = num_pages_buffer + num_pages_dir;
+
+ ret = alloc_int_buffers(buf, num_pages_dir,
+ num_pages_buffer, num_grefs);
+ if (ret < 0)
+ return ret;
+
+ ret = grant_references(xb_dev, buf, num_pages_dir, num_pages_buffer,
+ num_grefs);
+ if (ret < 0)
+ return ret;
+
+ fill_page_dir(buf, num_pages_dir);
+ return 0;
+}
diff --git a/sound/xen/xen_snd_front_shbuf.h b/sound/xen/xen_snd_front_shbuf.h
new file mode 100644
index 000000000000..d28e97c47b2c
--- /dev/null
+++ b/sound/xen/xen_snd_front_shbuf.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0 OR MIT */
+
+/*
+ * Xen para-virtual sound device
+ *
+ * Copyright (C) 2016-2018 EPAM Systems Inc.
+ *
+ * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
+ */
+
+#ifndef __XEN_SND_FRONT_SHBUF_H
+#define __XEN_SND_FRONT_SHBUF_H
+
+#include <xen/grant_table.h>
+
+#include "xen_snd_front_evtchnl.h"
+
+struct xen_snd_front_shbuf {
+ int num_grefs;
+ grant_ref_t *grefs;
+ u8 *directory;
+ u8 *buffer;
+ size_t buffer_sz;
+};
+
+grant_ref_t xen_snd_front_shbuf_get_dir_start(struct xen_snd_front_shbuf *buf);
+
+int xen_snd_front_shbuf_alloc(struct xenbus_device *xb_dev,
+ struct xen_snd_front_shbuf *buf,
+ unsigned int buffer_sz);
+
+void xen_snd_front_shbuf_clear(struct xen_snd_front_shbuf *buf);
+
+void xen_snd_front_shbuf_free(struct xen_snd_front_shbuf *buf);
+
+#endif /* __XEN_SND_FRONT_SHBUF_H */
--
2.16.2
^ permalink raw reply related [flat|nested] 40+ messages in thread
* [PATCH v2 5/5] ALSA: xen-front: Implement ALSA virtual sound driver
2018-04-16 6:24 [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver Oleksandr Andrushchenko
` (3 preceding siblings ...)
2018-04-16 6:24 ` [PATCH v2 4/5] ALSA: xen-front: Implement handling of shared buffers Oleksandr Andrushchenko
@ 2018-04-16 6:24 ` Oleksandr Andrushchenko
2018-04-16 14:09 ` Juergen Gross
2018-04-16 14:59 ` kbuild test robot
2018-04-17 12:42 ` [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver Oleksandr Andrushchenko
` (2 subsequent siblings)
7 siblings, 2 replies; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-16 6:24 UTC (permalink / raw)
To: xen-devel, linux-kernel, alsa-devel, jgross, boris.ostrovsky,
konrad.wilk, perex, tiwai
Cc: andr2000, Oleksandr Andrushchenko
From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Implement essential initialization of the sound driver:
- introduce required data structures
- handle driver registration
- handle sound card registration
- register sound driver on backend connection
- remove sound driver on backend disconnect
Initialize virtual sound card with streams according to the
Xen store configuration.
Implement ALSA driver operations including:
- manage frontend/backend shared buffers
- manage Xen bus event channel states
Implement requests from front to back for ALSA
PCM operations.
- report ALSA period elapsed event: handle XENSND_EVT_CUR_POS
notifications from the backend when stream position advances
during playback/capture. The event carries a value of how
many octets were played/captured at the time of the event.
- implement explicit stream parameter negotiation between
backend and frontend: handle XENSND_OP_HW_PARAM_QUERY request
to read/update configuration space for the parameter given:
request passes desired parameter interval and the response to
this request returns min/max interval for the parameter to be used.
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
---
sound/xen/Makefile | 3 +-
sound/xen/xen_snd_front.c | 193 ++++++++-
sound/xen/xen_snd_front.h | 28 ++
sound/xen/xen_snd_front_alsa.c | 830 ++++++++++++++++++++++++++++++++++++++
sound/xen/xen_snd_front_alsa.h | 23 ++
sound/xen/xen_snd_front_evtchnl.c | 6 +-
6 files changed, 1080 insertions(+), 3 deletions(-)
create mode 100644 sound/xen/xen_snd_front_alsa.c
create mode 100644 sound/xen/xen_snd_front_alsa.h
diff --git a/sound/xen/Makefile b/sound/xen/Makefile
index f028bc30af5d..1e6470ecc2f2 100644
--- a/sound/xen/Makefile
+++ b/sound/xen/Makefile
@@ -3,6 +3,7 @@
snd_xen_front-objs := xen_snd_front.o \
xen_snd_front_cfg.o \
xen_snd_front_evtchnl.o \
- xen_snd_front_shbuf.o
+ xen_snd_front_shbuf.o \
+ xen_snd_front_alsa.o
obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
index 0569c6c596a3..1fef253ea21a 100644
--- a/sound/xen/xen_snd_front.c
+++ b/sound/xen/xen_snd_front.c
@@ -19,10 +19,201 @@
#include <xen/interface/io/sndif.h>
#include "xen_snd_front.h"
+#include "xen_snd_front_alsa.h"
#include "xen_snd_front_evtchnl.h"
+#include "xen_snd_front_shbuf.h"
+
+static struct xensnd_req *
+be_stream_prepare_req(struct xen_snd_front_evtchnl *evtchnl, u8 operation)
+{
+ struct xensnd_req *req;
+
+ req = RING_GET_REQUEST(&evtchnl->u.req.ring,
+ evtchnl->u.req.ring.req_prod_pvt);
+ req->operation = operation;
+ req->id = evtchnl->evt_next_id++;
+ evtchnl->evt_id = req->id;
+ return req;
+}
+
+static int be_stream_do_io(struct xen_snd_front_evtchnl *evtchnl)
+{
+ if (unlikely(evtchnl->state != EVTCHNL_STATE_CONNECTED))
+ return -EIO;
+
+ reinit_completion(&evtchnl->u.req.completion);
+ xen_snd_front_evtchnl_flush(evtchnl);
+ return 0;
+}
+
+static int be_stream_wait_io(struct xen_snd_front_evtchnl *evtchnl)
+{
+ if (wait_for_completion_timeout(&evtchnl->u.req.completion,
+ msecs_to_jiffies(VSND_WAIT_BACK_MS)) <= 0)
+ return -ETIMEDOUT;
+
+ return evtchnl->u.req.resp_status;
+}
+
+int xen_snd_front_stream_query_hw_param(struct xen_snd_front_evtchnl *evtchnl,
+ struct xensnd_query_hw_param *hw_param_req,
+ struct xensnd_query_hw_param *hw_param_resp)
+{
+ struct xen_snd_front_info *front_info = evtchnl->front_info;
+ struct xensnd_req *req;
+ unsigned long flags;
+ int ret;
+
+ mutex_lock(&evtchnl->u.req.req_io_lock);
+
+ spin_lock_irqsave(&front_info->io_lock, flags);
+ req = be_stream_prepare_req(evtchnl, XENSND_OP_HW_PARAM_QUERY);
+ req->op.hw_param = *hw_param_req;
+
+ ret = be_stream_do_io(evtchnl);
+ spin_unlock_irqrestore(&front_info->io_lock, flags);
+
+ if (ret == 0)
+ ret = be_stream_wait_io(evtchnl);
+
+ if (ret == 0)
+ *hw_param_resp = evtchnl->u.req.resp.hw_param;
+
+ mutex_unlock(&evtchnl->u.req.req_io_lock);
+ return ret;
+}
+
+int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl *evtchnl,
+ struct xen_snd_front_shbuf *sh_buf,
+ u8 format, unsigned int channels,
+ unsigned int rate, u32 buffer_sz,
+ u32 period_sz)
+{
+ struct xen_snd_front_info *front_info = evtchnl->front_info;
+ struct xensnd_req *req;
+ unsigned long flags;
+ int ret;
+
+ mutex_lock(&evtchnl->u.req.req_io_lock);
+
+ spin_lock_irqsave(&front_info->io_lock, flags);
+ req = be_stream_prepare_req(evtchnl, XENSND_OP_OPEN);
+ req->op.open.pcm_format = format;
+ req->op.open.pcm_channels = channels;
+ req->op.open.pcm_rate = rate;
+ req->op.open.buffer_sz = buffer_sz;
+ req->op.open.period_sz = period_sz;
+ req->op.open.gref_directory = xen_snd_front_shbuf_get_dir_start(sh_buf);
+
+ ret = be_stream_do_io(evtchnl);
+ spin_unlock_irqrestore(&front_info->io_lock, flags);
+
+ if (ret == 0)
+ ret = be_stream_wait_io(evtchnl);
+
+ mutex_unlock(&evtchnl->u.req.req_io_lock);
+ return ret;
+}
+
+int xen_snd_front_stream_close(struct xen_snd_front_evtchnl *evtchnl)
+{
+ struct xen_snd_front_info *front_info = evtchnl->front_info;
+ struct xensnd_req *req;
+ unsigned long flags;
+ int ret;
+
+ mutex_lock(&evtchnl->u.req.req_io_lock);
+
+ spin_lock_irqsave(&front_info->io_lock, flags);
+ req = be_stream_prepare_req(evtchnl, XENSND_OP_CLOSE);
+
+ ret = be_stream_do_io(evtchnl);
+ spin_unlock_irqrestore(&front_info->io_lock, flags);
+
+ if (ret == 0)
+ ret = be_stream_wait_io(evtchnl);
+
+ mutex_unlock(&evtchnl->u.req.req_io_lock);
+ return ret;
+}
+
+int xen_snd_front_stream_write(struct xen_snd_front_evtchnl *evtchnl,
+ unsigned long pos, unsigned long count)
+{
+ struct xen_snd_front_info *front_info = evtchnl->front_info;
+ struct xensnd_req *req;
+ unsigned long flags;
+ int ret;
+
+ mutex_lock(&evtchnl->u.req.req_io_lock);
+
+ spin_lock_irqsave(&front_info->io_lock, flags);
+ req = be_stream_prepare_req(evtchnl, XENSND_OP_WRITE);
+ req->op.rw.length = count;
+ req->op.rw.offset = pos;
+
+ ret = be_stream_do_io(evtchnl);
+ spin_unlock_irqrestore(&front_info->io_lock, flags);
+
+ if (ret == 0)
+ ret = be_stream_wait_io(evtchnl);
+
+ mutex_unlock(&evtchnl->u.req.req_io_lock);
+ return ret;
+}
+
+int xen_snd_front_stream_read(struct xen_snd_front_evtchnl *evtchnl,
+ unsigned long pos, unsigned long count)
+{
+ struct xen_snd_front_info *front_info = evtchnl->front_info;
+ struct xensnd_req *req;
+ unsigned long flags;
+ int ret;
+
+ mutex_lock(&evtchnl->u.req.req_io_lock);
+
+ spin_lock_irqsave(&front_info->io_lock, flags);
+ req = be_stream_prepare_req(evtchnl, XENSND_OP_READ);
+ req->op.rw.length = count;
+ req->op.rw.offset = pos;
+
+ ret = be_stream_do_io(evtchnl);
+ spin_unlock_irqrestore(&front_info->io_lock, flags);
+
+ if (ret == 0)
+ ret = be_stream_wait_io(evtchnl);
+
+ mutex_unlock(&evtchnl->u.req.req_io_lock);
+ return ret;
+}
+
+int xen_snd_front_stream_trigger(struct xen_snd_front_evtchnl *evtchnl,
+ int type)
+{
+ struct xen_snd_front_info *front_info = evtchnl->front_info;
+ struct xensnd_req *req;
+ unsigned long flags;
+ int ret;
+
+ mutex_lock(&evtchnl->u.req.req_io_lock);
+
+ spin_lock_irqsave(&front_info->io_lock, flags);
+ req = be_stream_prepare_req(evtchnl, XENSND_OP_TRIGGER);
+ req->op.trigger.type = type;
+
+ ret = be_stream_do_io(evtchnl);
+ spin_unlock_irqrestore(&front_info->io_lock, flags);
+
+ if (ret == 0)
+ ret = be_stream_wait_io(evtchnl);
+
+ mutex_unlock(&evtchnl->u.req.req_io_lock);
+ return ret;
+}
static void xen_snd_drv_fini(struct xen_snd_front_info *front_info)
{
+ xen_snd_front_alsa_fini(front_info);
xen_snd_front_evtchnl_free_all(front_info);
}
@@ -45,7 +236,7 @@ static int sndback_initwait(struct xen_snd_front_info *front_info)
static int sndback_connect(struct xen_snd_front_info *front_info)
{
- return 0;
+ return xen_snd_front_alsa_init(front_info);
}
static void sndback_disconnect(struct xen_snd_front_info *front_info)
diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
index 9c2ffbb4e4b8..7adbdb4d2019 100644
--- a/sound/xen/xen_snd_front.h
+++ b/sound/xen/xen_snd_front.h
@@ -13,17 +13,45 @@
#include "xen_snd_front_cfg.h"
+struct card_info;
+struct xen_snd_front_evtchnl;
struct xen_snd_front_evtchnl_pair;
+struct xen_snd_front_shbuf;
+struct xensnd_query_hw_param;
struct xen_snd_front_info {
struct xenbus_device *xb_dev;
+ struct card_info *card_info;
+
/* serializer for backend IO: request/response */
spinlock_t io_lock;
+
int num_evt_pairs;
struct xen_snd_front_evtchnl_pair *evt_pairs;
struct xen_front_cfg_card cfg;
};
+int xen_snd_front_stream_query_hw_param(struct xen_snd_front_evtchnl *evtchnl,
+ struct xensnd_query_hw_param *hw_param_req,
+ struct xensnd_query_hw_param *hw_param_resp);
+
+int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl *evtchnl,
+ struct xen_snd_front_shbuf *sh_buf,
+ u8 format, unsigned int channels,
+ unsigned int rate, u32 buffer_sz,
+ u32 period_sz);
+
+int xen_snd_front_stream_close(struct xen_snd_front_evtchnl *evtchnl);
+
+int xen_snd_front_stream_write(struct xen_snd_front_evtchnl *evtchnl,
+ unsigned long pos, unsigned long count);
+
+int xen_snd_front_stream_read(struct xen_snd_front_evtchnl *evtchnl,
+ unsigned long pos, unsigned long count);
+
+int xen_snd_front_stream_trigger(struct xen_snd_front_evtchnl *evtchnl,
+ int type);
+
#endif /* __XEN_SND_FRONT_H */
diff --git a/sound/xen/xen_snd_front_alsa.c b/sound/xen/xen_snd_front_alsa.c
new file mode 100644
index 000000000000..f524b172750e
--- /dev/null
+++ b/sound/xen/xen_snd_front_alsa.c
@@ -0,0 +1,830 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+
+/*
+ * Xen para-virtual sound device
+ *
+ * Copyright (C) 2016-2018 EPAM Systems Inc.
+ *
+ * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
+ */
+
+#include <linux/platform_device.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+
+#include <xen/xenbus.h>
+
+#include "xen_snd_front.h"
+#include "xen_snd_front_alsa.h"
+#include "xen_snd_front_cfg.h"
+#include "xen_snd_front_evtchnl.h"
+#include "xen_snd_front_shbuf.h"
+
+struct pcm_stream_info {
+ struct xen_snd_front_info *front_info;
+ struct xen_snd_front_evtchnl_pair *evt_pair;
+ struct xen_snd_front_shbuf sh_buf;
+ int index;
+
+ bool is_open;
+ struct snd_pcm_hardware pcm_hw;
+
+ /* number of processed frames as reported by the backend */
+ snd_pcm_uframes_t be_cur_frame;
+ /* current HW pointer to be reported via .period callback */
+ atomic_t hw_ptr;
+ /* modulo of the number of processed frames - for period detection */
+ u32 out_frames;
+};
+
+struct pcm_instance_info {
+ struct card_info *card_info;
+ struct snd_pcm *pcm;
+ struct snd_pcm_hardware pcm_hw;
+ int num_pcm_streams_pb;
+ struct pcm_stream_info *streams_pb;
+ int num_pcm_streams_cap;
+ struct pcm_stream_info *streams_cap;
+};
+
+struct card_info {
+ struct xen_snd_front_info *front_info;
+ struct snd_card *card;
+ struct snd_pcm_hardware pcm_hw;
+ int num_pcm_instances;
+ struct pcm_instance_info *pcm_instances;
+};
+
+struct alsa_sndif_sample_format {
+ u8 sndif;
+ snd_pcm_format_t alsa;
+};
+
+struct alsa_sndif_hw_param {
+ u8 sndif;
+ snd_pcm_hw_param_t alsa;
+};
+
+static const struct alsa_sndif_sample_format ALSA_SNDIF_FORMATS[] = {
+ {
+ .sndif = XENSND_PCM_FORMAT_U8,
+ .alsa = SNDRV_PCM_FORMAT_U8
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_S8,
+ .alsa = SNDRV_PCM_FORMAT_S8
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_U16_LE,
+ .alsa = SNDRV_PCM_FORMAT_U16_LE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_U16_BE,
+ .alsa = SNDRV_PCM_FORMAT_U16_BE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_S16_LE,
+ .alsa = SNDRV_PCM_FORMAT_S16_LE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_S16_BE,
+ .alsa = SNDRV_PCM_FORMAT_S16_BE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_U24_LE,
+ .alsa = SNDRV_PCM_FORMAT_U24_LE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_U24_BE,
+ .alsa = SNDRV_PCM_FORMAT_U24_BE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_S24_LE,
+ .alsa = SNDRV_PCM_FORMAT_S24_LE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_S24_BE,
+ .alsa = SNDRV_PCM_FORMAT_S24_BE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_U32_LE,
+ .alsa = SNDRV_PCM_FORMAT_U32_LE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_U32_BE,
+ .alsa = SNDRV_PCM_FORMAT_U32_BE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_S32_LE,
+ .alsa = SNDRV_PCM_FORMAT_S32_LE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_S32_BE,
+ .alsa = SNDRV_PCM_FORMAT_S32_BE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_A_LAW,
+ .alsa = SNDRV_PCM_FORMAT_A_LAW
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_MU_LAW,
+ .alsa = SNDRV_PCM_FORMAT_MU_LAW
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_F32_LE,
+ .alsa = SNDRV_PCM_FORMAT_FLOAT_LE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_F32_BE,
+ .alsa = SNDRV_PCM_FORMAT_FLOAT_BE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_F64_LE,
+ .alsa = SNDRV_PCM_FORMAT_FLOAT64_LE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_F64_BE,
+ .alsa = SNDRV_PCM_FORMAT_FLOAT64_BE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE,
+ .alsa = SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE,
+ .alsa = SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_IMA_ADPCM,
+ .alsa = SNDRV_PCM_FORMAT_IMA_ADPCM
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_MPEG,
+ .alsa = SNDRV_PCM_FORMAT_MPEG
+ },
+ {
+ .sndif = XENSND_PCM_FORMAT_GSM,
+ .alsa = SNDRV_PCM_FORMAT_GSM
+ },
+};
+
+static int to_sndif_format(snd_pcm_format_t format)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
+ if (ALSA_SNDIF_FORMATS[i].alsa == format)
+ return ALSA_SNDIF_FORMATS[i].sndif;
+
+ return -EINVAL;
+}
+
+static u64 to_sndif_formats_mask(u64 alsa_formats)
+{
+ u64 mask;
+ int i;
+
+ mask = 0;
+ for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
+ if (1 << ALSA_SNDIF_FORMATS[i].alsa & alsa_formats)
+ mask |= 1 << ALSA_SNDIF_FORMATS[i].sndif;
+
+ return mask;
+}
+
+static u64 to_alsa_formats_mask(u64 sndif_formats)
+{
+ u64 mask;
+ int i;
+
+ mask = 0;
+ for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
+ if (1 << ALSA_SNDIF_FORMATS[i].sndif & sndif_formats)
+ mask |= 1 << ALSA_SNDIF_FORMATS[i].alsa;
+
+ return mask;
+}
+
+static void stream_clear(struct pcm_stream_info *stream)
+{
+ stream->is_open = false;
+ stream->be_cur_frame = 0;
+ stream->out_frames = 0;
+ atomic_set(&stream->hw_ptr, 0);
+ xen_snd_front_evtchnl_pair_clear(stream->evt_pair);
+ xen_snd_front_shbuf_clear(&stream->sh_buf);
+}
+
+static void stream_free(struct pcm_stream_info *stream)
+{
+ xen_snd_front_shbuf_free(&stream->sh_buf);
+ stream_clear(stream);
+}
+
+static struct pcm_stream_info *stream_get(struct snd_pcm_substream *substream)
+{
+ struct pcm_instance_info *pcm_instance =
+ snd_pcm_substream_chip(substream);
+ struct pcm_stream_info *stream;
+
+ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+ stream = &pcm_instance->streams_pb[substream->number];
+ else
+ stream = &pcm_instance->streams_cap[substream->number];
+
+ return stream;
+}
+
+static int alsa_hw_rule(struct snd_pcm_hw_params *params,
+ struct snd_pcm_hw_rule *rule)
+{
+ struct pcm_stream_info *stream = rule->private;
+ struct device *dev = &stream->front_info->xb_dev->dev;
+ struct snd_mask *formats =
+ hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
+ struct snd_interval *rates =
+ hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
+ struct snd_interval *channels =
+ hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
+ struct snd_interval *period =
+ hw_param_interval(params,
+ SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
+ struct snd_interval *buffer =
+ hw_param_interval(params,
+ SNDRV_PCM_HW_PARAM_BUFFER_SIZE);
+ struct xensnd_query_hw_param req;
+ struct xensnd_query_hw_param resp;
+ struct snd_interval interval;
+ struct snd_mask mask;
+ u64 sndif_formats;
+ int changed, ret;
+
+ /* collect all the values we need for the query */
+
+ req.formats = to_sndif_formats_mask((u64)formats->bits[0] |
+ (u64)(formats->bits[1]) << 32);
+
+ req.rates.min = rates->min;
+ req.rates.max = rates->max;
+
+ req.channels.min = channels->min;
+ req.channels.max = channels->max;
+
+ req.buffer.min = buffer->min;
+ req.buffer.max = buffer->max;
+
+ req.period.min = period->min;
+ req.period.max = period->max;
+
+ ret = xen_snd_front_stream_query_hw_param(&stream->evt_pair->req,
+ &req, &resp);
+ if (ret < 0) {
+ /* check if this is due to backend communication error */
+ if (ret == -EIO || ret == -ETIMEDOUT)
+ dev_err(dev, "Failed to query ALSA HW parameters\n");
+ return ret;
+ }
+
+ /* refine HW parameters after the query */
+ changed = 0;
+
+ sndif_formats = to_alsa_formats_mask(resp.formats);
+ snd_mask_none(&mask);
+ mask.bits[0] = (u32)sndif_formats;
+ mask.bits[1] = (u32)(sndif_formats >> 32);
+ ret = snd_mask_refine(formats, &mask);
+ if (ret < 0)
+ return ret;
+ changed |= ret;
+
+ interval.openmin = 0;
+ interval.openmax = 0;
+ interval.integer = 1;
+
+ interval.min = resp.rates.min;
+ interval.max = resp.rates.max;
+ ret = snd_interval_refine(rates, &interval);
+ if (ret < 0)
+ return ret;
+ changed |= ret;
+
+ interval.min = resp.channels.min;
+ interval.max = resp.channels.max;
+ ret = snd_interval_refine(channels, &interval);
+ if (ret < 0)
+ return ret;
+ changed |= ret;
+
+ interval.min = resp.buffer.min;
+ interval.max = resp.buffer.max;
+ ret = snd_interval_refine(buffer, &interval);
+ if (ret < 0)
+ return ret;
+ changed |= ret;
+
+ interval.min = resp.period.min;
+ interval.max = resp.period.max;
+ ret = snd_interval_refine(period, &interval);
+ if (ret < 0)
+ return ret;
+ changed |= ret;
+
+ return changed;
+}
+
+static int alsa_open(struct snd_pcm_substream *substream)
+{
+ struct pcm_instance_info *pcm_instance =
+ snd_pcm_substream_chip(substream);
+ struct pcm_stream_info *stream = stream_get(substream);
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct xen_snd_front_info *front_info =
+ pcm_instance->card_info->front_info;
+ struct device *dev = &front_info->xb_dev->dev;
+ unsigned long flags;
+ int ret;
+
+ /*
+ * return our HW properties: override defaults with those configured
+ * via XenStore
+ */
+ runtime->hw = stream->pcm_hw;
+ runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |
+ SNDRV_PCM_INFO_MMAP_VALID |
+ SNDRV_PCM_INFO_DOUBLE |
+ SNDRV_PCM_INFO_BATCH |
+ SNDRV_PCM_INFO_NONINTERLEAVED |
+ SNDRV_PCM_INFO_RESUME |
+ SNDRV_PCM_INFO_PAUSE);
+ runtime->hw.info |= SNDRV_PCM_INFO_INTERLEAVED;
+
+ spin_lock_irqsave(&front_info->io_lock, flags);
+
+ stream->evt_pair = &front_info->evt_pairs[stream->index];
+
+ stream->front_info = front_info;
+
+ xen_snd_front_evtchnl_pair_set_connected(stream->evt_pair, true);
+
+ stream->evt_pair->evt.u.evt.substream = substream;
+
+ stream_clear(stream);
+
+ spin_unlock_irqrestore(&front_info->io_lock, flags);
+
+ ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
+ alsa_hw_rule, stream,
+ SNDRV_PCM_HW_PARAM_FORMAT, -1);
+ if (ret) {
+ dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_FORMAT\n");
+ return ret;
+ }
+
+ ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
+ alsa_hw_rule, stream,
+ SNDRV_PCM_HW_PARAM_RATE, -1);
+ if (ret) {
+ dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_RATE\n");
+ return ret;
+ }
+
+ ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
+ alsa_hw_rule, stream,
+ SNDRV_PCM_HW_PARAM_CHANNELS, -1);
+ if (ret) {
+ dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_CHANNELS\n");
+ return ret;
+ }
+
+ ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
+ alsa_hw_rule, stream,
+ SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
+ if (ret) {
+ dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_PERIOD_SIZE\n");
+ return ret;
+ }
+
+ ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
+ alsa_hw_rule, stream,
+ SNDRV_PCM_HW_PARAM_BUFFER_SIZE, -1);
+ if (ret) {
+ dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_BUFFER_SIZE\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int alsa_close(struct snd_pcm_substream *substream)
+{
+ struct pcm_stream_info *stream = stream_get(substream);
+ unsigned long flags;
+
+ spin_lock_irqsave(&stream->front_info->io_lock, flags);
+
+ xen_snd_front_evtchnl_pair_set_connected(stream->evt_pair, false);
+
+ spin_unlock_irqrestore(&stream->front_info->io_lock, flags);
+ return 0;
+}
+
+static int alsa_hw_params(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *params)
+{
+ struct pcm_stream_info *stream = stream_get(substream);
+ int ret;
+
+ /*
+ * this callback may be called multiple times,
+ * so free the previously allocated shared buffer if any
+ */
+ stream_free(stream);
+
+ ret = xen_snd_front_shbuf_alloc(stream->front_info->xb_dev,
+ &stream->sh_buf,
+ params_buffer_bytes(params));
+ if (ret < 0) {
+ stream_free(stream);
+ dev_err(&stream->front_info->xb_dev->dev,
+ "Failed to allocate buffers for stream with index %d\n",
+ stream->index);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int alsa_hw_free(struct snd_pcm_substream *substream)
+{
+ struct pcm_stream_info *stream = stream_get(substream);
+ int ret;
+
+ ret = xen_snd_front_stream_close(&stream->evt_pair->req);
+ stream_free(stream);
+ return ret;
+}
+
+static int alsa_prepare(struct snd_pcm_substream *substream)
+{
+ struct pcm_stream_info *stream = stream_get(substream);
+
+ if (!stream->is_open) {
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ u8 sndif_format;
+ int ret;
+
+ sndif_format = to_sndif_format(runtime->format);
+ if (sndif_format < 0) {
+ dev_err(&stream->front_info->xb_dev->dev,
+ "Unsupported sample format: %d\n",
+ runtime->format);
+ return sndif_format;
+ }
+
+ ret = xen_snd_front_stream_prepare(&stream->evt_pair->req,
+ &stream->sh_buf,
+ sndif_format,
+ runtime->channels,
+ runtime->rate,
+ snd_pcm_lib_buffer_bytes(substream),
+ snd_pcm_lib_period_bytes(substream));
+ if (ret < 0)
+ return ret;
+
+ stream->is_open = true;
+ }
+
+ return 0;
+}
+
+static int alsa_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+ struct pcm_stream_info *stream = stream_get(substream);
+ int type;
+
+ switch (cmd) {
+ case SNDRV_PCM_TRIGGER_START:
+ type = XENSND_OP_TRIGGER_START;
+ break;
+
+ case SNDRV_PCM_TRIGGER_RESUME:
+ type = XENSND_OP_TRIGGER_RESUME;
+ break;
+
+ case SNDRV_PCM_TRIGGER_STOP:
+ type = XENSND_OP_TRIGGER_STOP;
+ break;
+
+ case SNDRV_PCM_TRIGGER_SUSPEND:
+ type = XENSND_OP_TRIGGER_PAUSE;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ return xen_snd_front_stream_trigger(&stream->evt_pair->req, type);
+}
+
+void xen_snd_front_alsa_handle_cur_pos(struct xen_snd_front_evtchnl *evtchnl,
+ u64 pos_bytes)
+{
+ struct snd_pcm_substream *substream = evtchnl->u.evt.substream;
+ struct pcm_stream_info *stream = stream_get(substream);
+ snd_pcm_uframes_t delta, new_hw_ptr, cur_frame;
+
+ cur_frame = bytes_to_frames(substream->runtime, pos_bytes);
+
+ delta = cur_frame - stream->be_cur_frame;
+ stream->be_cur_frame = cur_frame;
+
+ new_hw_ptr = (snd_pcm_uframes_t)atomic_read(&stream->hw_ptr);
+ new_hw_ptr = (new_hw_ptr + delta) % substream->runtime->buffer_size;
+ atomic_set(&stream->hw_ptr, (int)new_hw_ptr);
+
+ stream->out_frames += delta;
+ if (stream->out_frames > substream->runtime->period_size) {
+ stream->out_frames %= substream->runtime->period_size;
+ snd_pcm_period_elapsed(substream);
+ }
+}
+
+static snd_pcm_uframes_t alsa_pointer(struct snd_pcm_substream *substream)
+{
+ struct pcm_stream_info *stream = stream_get(substream);
+
+ return (snd_pcm_uframes_t)atomic_read(&stream->hw_ptr);
+}
+
+static int alsa_pb_copy_user(struct snd_pcm_substream *substream,
+ int channel, unsigned long pos, void __user *src,
+ unsigned long count)
+{
+ struct pcm_stream_info *stream = stream_get(substream);
+
+ if (unlikely(pos + count > stream->sh_buf.buffer_sz))
+ return -EINVAL;
+
+ if (copy_from_user(stream->sh_buf.buffer + pos, src, count))
+ return -EFAULT;
+
+ return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
+}
+
+static int alsa_pb_copy_kernel(struct snd_pcm_substream *substream,
+ int channel, unsigned long pos, void *src,
+ unsigned long count)
+{
+ struct pcm_stream_info *stream = stream_get(substream);
+
+ if (unlikely(pos + count > stream->sh_buf.buffer_sz))
+ return -EINVAL;
+
+ memcpy(stream->sh_buf.buffer + pos, src, count);
+
+ return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
+}
+
+static int alsa_cap_copy_user(struct snd_pcm_substream *substream,
+ int channel, unsigned long pos, void __user *dst,
+ unsigned long count)
+{
+ struct pcm_stream_info *stream = stream_get(substream);
+ int ret;
+
+ if (unlikely(pos + count > stream->sh_buf.buffer_sz))
+ return -EINVAL;
+
+ ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos, count);
+ if (ret < 0)
+ return ret;
+
+ return copy_to_user(dst, stream->sh_buf.buffer + pos, count) ?
+ -EFAULT : 0;
+}
+
+static int alsa_cap_copy_kernel(struct snd_pcm_substream *substream,
+ int channel, unsigned long pos, void *dst,
+ unsigned long count)
+{
+ struct pcm_stream_info *stream = stream_get(substream);
+ int ret;
+
+ if (unlikely(pos + count > stream->sh_buf.buffer_sz))
+ return -EINVAL;
+
+ ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos, count);
+ if (ret < 0)
+ return ret;
+
+ memcpy(dst, stream->sh_buf.buffer + pos, count);
+
+ return 0;
+}
+
+static int alsa_pb_fill_silence(struct snd_pcm_substream *substream,
+ int channel, unsigned long pos,
+ unsigned long count)
+{
+ struct pcm_stream_info *stream = stream_get(substream);
+
+ if (unlikely(pos + count > stream->sh_buf.buffer_sz))
+ return -EINVAL;
+
+ memset(stream->sh_buf.buffer + pos, 0, count);
+
+ return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
+}
+
+/*
+ * FIXME: The mmaped data transfer is asynchronous and there is no
+ * ack signal from user-space when it is done. This is the
+ * reason it is not implemented in the PV driver as we do need
+ * to know when the buffer can be transferred to the backend.
+ */
+
+static struct snd_pcm_ops snd_drv_alsa_playback_ops = {
+ .open = alsa_open,
+ .close = alsa_close,
+ .ioctl = snd_pcm_lib_ioctl,
+ .hw_params = alsa_hw_params,
+ .hw_free = alsa_hw_free,
+ .prepare = alsa_prepare,
+ .trigger = alsa_trigger,
+ .pointer = alsa_pointer,
+ .copy_user = alsa_pb_copy_user,
+ .copy_kernel = alsa_pb_copy_kernel,
+ .fill_silence = alsa_pb_fill_silence,
+};
+
+static struct snd_pcm_ops snd_drv_alsa_capture_ops = {
+ .open = alsa_open,
+ .close = alsa_close,
+ .ioctl = snd_pcm_lib_ioctl,
+ .hw_params = alsa_hw_params,
+ .hw_free = alsa_hw_free,
+ .prepare = alsa_prepare,
+ .trigger = alsa_trigger,
+ .pointer = alsa_pointer,
+ .copy_user = alsa_cap_copy_user,
+ .copy_kernel = alsa_cap_copy_kernel,
+};
+
+static int new_pcm_instance(struct card_info *card_info,
+ struct xen_front_cfg_pcm_instance *instance_cfg,
+ struct pcm_instance_info *pcm_instance_info)
+{
+ struct snd_pcm *pcm;
+ int ret, i;
+
+ dev_dbg(&card_info->front_info->xb_dev->dev,
+ "New PCM device \"%s\" with id %d playback %d capture %d",
+ instance_cfg->name,
+ instance_cfg->device_id,
+ instance_cfg->num_streams_pb,
+ instance_cfg->num_streams_cap);
+
+ pcm_instance_info->card_info = card_info;
+
+ pcm_instance_info->pcm_hw = instance_cfg->pcm_hw;
+
+ if (instance_cfg->num_streams_pb) {
+ pcm_instance_info->streams_pb =
+ devm_kcalloc(&card_info->card->card_dev,
+ instance_cfg->num_streams_pb,
+ sizeof(struct pcm_stream_info),
+ GFP_KERNEL);
+ if (!pcm_instance_info->streams_pb)
+ return -ENOMEM;
+ }
+
+ if (instance_cfg->num_streams_cap) {
+ pcm_instance_info->streams_cap =
+ devm_kcalloc(&card_info->card->card_dev,
+ instance_cfg->num_streams_cap,
+ sizeof(struct pcm_stream_info),
+ GFP_KERNEL);
+ if (!pcm_instance_info->streams_cap)
+ return -ENOMEM;
+ }
+
+ pcm_instance_info->num_pcm_streams_pb =
+ instance_cfg->num_streams_pb;
+ pcm_instance_info->num_pcm_streams_cap =
+ instance_cfg->num_streams_cap;
+
+ for (i = 0; i < pcm_instance_info->num_pcm_streams_pb; i++) {
+ pcm_instance_info->streams_pb[i].pcm_hw =
+ instance_cfg->streams_pb[i].pcm_hw;
+ pcm_instance_info->streams_pb[i].index =
+ instance_cfg->streams_pb[i].index;
+ }
+
+ for (i = 0; i < pcm_instance_info->num_pcm_streams_cap; i++) {
+ pcm_instance_info->streams_cap[i].pcm_hw =
+ instance_cfg->streams_cap[i].pcm_hw;
+ pcm_instance_info->streams_cap[i].index =
+ instance_cfg->streams_cap[i].index;
+ }
+
+ ret = snd_pcm_new(card_info->card, instance_cfg->name,
+ instance_cfg->device_id,
+ instance_cfg->num_streams_pb,
+ instance_cfg->num_streams_cap,
+ &pcm);
+ if (ret < 0)
+ return ret;
+
+ pcm->private_data = pcm_instance_info;
+ pcm->info_flags = 0;
+ /* we want to handle all PCM operations in non-atomic context */
+ pcm->nonatomic = true;
+ strncpy(pcm->name, "Virtual card PCM", sizeof(pcm->name));
+
+ if (instance_cfg->num_streams_pb)
+ snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
+ &snd_drv_alsa_playback_ops);
+
+ if (instance_cfg->num_streams_cap)
+ snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,
+ &snd_drv_alsa_capture_ops);
+
+ pcm_instance_info->pcm = pcm;
+ return 0;
+}
+
+int xen_snd_front_alsa_init(struct xen_snd_front_info *front_info)
+{
+ struct device *dev = &front_info->xb_dev->dev;
+ struct xen_front_cfg_card *cfg = &front_info->cfg;
+ struct card_info *card_info;
+ struct snd_card *card;
+ int ret, i;
+
+ dev_dbg(dev, "Creating virtual sound card\n");
+
+ ret = snd_card_new(dev, 0, XENSND_DRIVER_NAME, THIS_MODULE,
+ sizeof(struct card_info), &card);
+ if (ret < 0)
+ return ret;
+
+ card_info = card->private_data;
+ card_info->front_info = front_info;
+ front_info->card_info = card_info;
+ card_info->card = card;
+ card_info->pcm_instances =
+ devm_kcalloc(dev, cfg->num_pcm_instances,
+ sizeof(struct pcm_instance_info),
+ GFP_KERNEL);
+ if (!card_info->pcm_instances) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ card_info->num_pcm_instances = cfg->num_pcm_instances;
+ card_info->pcm_hw = cfg->pcm_hw;
+
+ for (i = 0; i < cfg->num_pcm_instances; i++) {
+ ret = new_pcm_instance(card_info, &cfg->pcm_instances[i],
+ &card_info->pcm_instances[i]);
+ if (ret < 0)
+ goto fail;
+ }
+
+ strncpy(card->driver, XENSND_DRIVER_NAME, sizeof(card->driver));
+ strncpy(card->shortname, cfg->name_short, sizeof(card->shortname));
+ strncpy(card->longname, cfg->name_long, sizeof(card->longname));
+
+ ret = snd_card_register(card);
+ if (ret < 0)
+ goto fail;
+
+ return 0;
+
+fail:
+ snd_card_free(card);
+ return ret;
+}
+
+void xen_snd_front_alsa_fini(struct xen_snd_front_info *front_info)
+{
+ struct card_info *card_info;
+ struct snd_card *card;
+
+ card_info = front_info->card_info;
+ if (!card_info)
+ return;
+
+ card = card_info->card;
+ if (!card)
+ return;
+
+ dev_dbg(&front_info->xb_dev->dev, "Removing virtual sound card %d\n",
+ card->number);
+ snd_card_free(card);
+
+ /* card_info will be freed when destroying front_info->xb_dev->dev */
+ card_info->card = NULL;
+}
diff --git a/sound/xen/xen_snd_front_alsa.h b/sound/xen/xen_snd_front_alsa.h
new file mode 100644
index 000000000000..18abd9eec967
--- /dev/null
+++ b/sound/xen/xen_snd_front_alsa.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 OR MIT */
+
+/*
+ * Xen para-virtual sound device
+ *
+ * Copyright (C) 2016-2018 EPAM Systems Inc.
+ *
+ * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
+ */
+
+#ifndef __XEN_SND_FRONT_ALSA_H
+#define __XEN_SND_FRONT_ALSA_H
+
+struct xen_snd_front_info;
+
+int xen_snd_front_alsa_init(struct xen_snd_front_info *front_info);
+
+void xen_snd_front_alsa_fini(struct xen_snd_front_info *front_info);
+
+void xen_snd_front_alsa_handle_cur_pos(struct xen_snd_front_evtchnl *evtchnl,
+ u64 pos_bytes);
+
+#endif /* __XEN_SND_FRONT_ALSA_H */
diff --git a/sound/xen/xen_snd_front_evtchnl.c b/sound/xen/xen_snd_front_evtchnl.c
index 9ece39f938f8..470196518716 100644
--- a/sound/xen/xen_snd_front_evtchnl.c
+++ b/sound/xen/xen_snd_front_evtchnl.c
@@ -14,6 +14,7 @@
#include <xen/xenbus.h>
#include "xen_snd_front.h"
+#include "xen_snd_front_alsa.h"
#include "xen_snd_front_cfg.h"
#include "xen_snd_front_evtchnl.h"
@@ -111,7 +112,10 @@ static irqreturn_t evtchnl_interrupt_evt(int irq, void *dev_id)
switch (event->type) {
case XENSND_EVT_CUR_POS:
- /* do nothing at the moment */
+ spin_unlock_irqrestore(&front_info->io_lock, flags);
+ xen_snd_front_alsa_handle_cur_pos(channel,
+ event->op.cur_pos.position);
+ spin_lock_irqsave(&front_info->io_lock, flags);
break;
}
}
--
2.16.2
^ permalink raw reply related [flat|nested] 40+ messages in thread
* Re: [PATCH v2 1/5] ALSA: xen-front: Introduce Xen para-virtualized sound frontend driver
2018-04-16 6:24 ` [PATCH v2 1/5] ALSA: xen-front: Introduce Xen para-virtualized sound " Oleksandr Andrushchenko
@ 2018-04-16 12:25 ` Juergen Gross
2018-04-17 8:24 ` Oleksandr Andrushchenko
2018-04-24 13:55 ` Takashi Iwai
1 sibling, 1 reply; 40+ messages in thread
From: Juergen Gross @ 2018-04-16 12:25 UTC (permalink / raw)
To: Oleksandr Andrushchenko, xen-devel, linux-kernel, alsa-devel,
boris.ostrovsky, konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>
> Introduce skeleton of the para-virtualized Xen sound
> frontend driver.
>
> Initial handling for Xen bus states: implement
> Xen bus state machine for the frontend driver according to
> the state diagram and recovery flow from sound para-virtualized
> protocol: xen/interface/io/sndif.h.
>
> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Only one minor nit (see below). With that addressed (or fixed when
committing):
Reviewed-by: Juergen Gross <jgross@suse.com>
Juergen
> ---
> sound/Kconfig | 2 +
> sound/Makefile | 2 +-
> sound/xen/Kconfig | 10 +++
> sound/xen/Makefile | 5 ++
> sound/xen/xen_snd_front.c | 196 ++++++++++++++++++++++++++++++++++++++++++++++
> sound/xen/xen_snd_front.h | 18 +++++
> 6 files changed, 232 insertions(+), 1 deletion(-)
> create mode 100644 sound/xen/Kconfig
> create mode 100644 sound/xen/Makefile
> create mode 100644 sound/xen/xen_snd_front.c
> create mode 100644 sound/xen/xen_snd_front.h
>
> diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
> new file mode 100644
> index 000000000000..f406a8f52c51
> --- /dev/null
> +++ b/sound/xen/xen_snd_front.c
> @@ -0,0 +1,196 @@
> +static void sndback_changed(struct xenbus_device *xb_dev,
> + enum xenbus_state backend_state)
> +{
> + struct xen_snd_front_info *front_info = dev_get_drvdata(&xb_dev->dev);
> + int ret;
> +
> + dev_dbg(&xb_dev->dev, "Backend state is %s, front is %s\n",
> + xenbus_strstate(backend_state),
> + xenbus_strstate(xb_dev->state));
> +
> + switch (backend_state) {
> + case XenbusStateReconfiguring:
> + /* fall through */
> + case XenbusStateReconfigured:
> + /* fall through */
> + case XenbusStateInitialised:
> + /* fall through */
> + break;
> +
> + case XenbusStateInitialising:
> + /* recovering after backend unexpected closure */
> + sndback_disconnect(front_info);
> + break;
> +
> + case XenbusStateInitWait:
> + /* recovering after backend unexpected closure */
> + sndback_disconnect(front_info);
> +
> + ret = sndback_initwait(front_info);
> + if (ret < 0)
> + xenbus_dev_fatal(xb_dev, ret, "initializing frontend");
> + else
> + xenbus_switch_state(xb_dev, XenbusStateInitialised);
> + break;
> +
> + case XenbusStateConnected:
> + if (xb_dev->state != XenbusStateInitialised)
> + break;
> +
> + ret = sndback_connect(front_info);
> + if (ret < 0)
> + xenbus_dev_fatal(xb_dev, ret, "initializing frontend");
> + else
> + xenbus_switch_state(xb_dev, XenbusStateConnected);
> + break;
> +
> + case XenbusStateClosing:
> + /*
> + * in this state backend starts freeing resources,
> + * so let it go into closed state first, so we can also
> + * remove ours
> + */
Please start the sentence with a capital letter and end it with a
full stop.
Juergen
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 2/5] ALSA: xen-front: Read sound driver configuration from Xen store
2018-04-16 6:24 ` [PATCH v2 2/5] ALSA: xen-front: Read sound driver configuration from Xen store Oleksandr Andrushchenko
@ 2018-04-16 12:55 ` Juergen Gross
2018-04-17 8:42 ` Oleksandr Andrushchenko
0 siblings, 1 reply; 40+ messages in thread
From: Juergen Gross @ 2018-04-16 12:55 UTC (permalink / raw)
To: Oleksandr Andrushchenko, xen-devel, linux-kernel, alsa-devel,
boris.ostrovsky, konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>
> Read configuration values from Xen store according
> to xen/interface/io/sndif.h protocol:
> - introduce configuration structures for different
> components, e.g. sound card, device, stream
> - read PCM HW parameters, e.g rate, format etc.
> - detect stream type (capture/playback)
> - read device and card parameters
>
> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> ---
> sound/xen/Makefile | 3 +-
> sound/xen/xen_snd_front.c | 7 +
> sound/xen/xen_snd_front.h | 4 +
> sound/xen/xen_snd_front_cfg.c | 517 ++++++++++++++++++++++++++++++++++++++++++
> sound/xen/xen_snd_front_cfg.h | 46 ++++
> 5 files changed, 576 insertions(+), 1 deletion(-)
> create mode 100644 sound/xen/xen_snd_front_cfg.c
> create mode 100644 sound/xen/xen_snd_front_cfg.h
>
> diff --git a/sound/xen/Makefile b/sound/xen/Makefile
> index 4507ef3c27fd..06705bef61fa 100644
> --- a/sound/xen/Makefile
> +++ b/sound/xen/Makefile
> @@ -1,5 +1,6 @@
> # SPDX-License-Identifier: GPL-2.0 OR MIT
>
> -snd_xen_front-objs := xen_snd_front.o
> +snd_xen_front-objs := xen_snd_front.o \
> + xen_snd_front_cfg.o
>
> obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
> diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
> index f406a8f52c51..65d2494a9d14 100644
> --- a/sound/xen/xen_snd_front.c
> +++ b/sound/xen/xen_snd_front.c
> @@ -25,6 +25,13 @@ static void xen_snd_drv_fini(struct xen_snd_front_info *front_info)
>
> static int sndback_initwait(struct xen_snd_front_info *front_info)
> {
> + int num_streams;
> + int ret;
> +
> + ret = xen_snd_front_cfg_card(front_info, &num_streams);
> + if (ret < 0)
> + return ret;
> +
> return 0;
> }
>
> diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
> index 4ae204b23d32..b52226cb30bc 100644
> --- a/sound/xen/xen_snd_front.h
> +++ b/sound/xen/xen_snd_front.h
> @@ -11,8 +11,12 @@
> #ifndef __XEN_SND_FRONT_H
> #define __XEN_SND_FRONT_H
>
> +#include "xen_snd_front_cfg.h"
> +
> struct xen_snd_front_info {
> struct xenbus_device *xb_dev;
> +
> + struct xen_front_cfg_card cfg;
> };
>
> #endif /* __XEN_SND_FRONT_H */
> diff --git a/sound/xen/xen_snd_front_cfg.c b/sound/xen/xen_snd_front_cfg.c
> new file mode 100644
> index 000000000000..d461985afffa
> --- /dev/null
> +++ b/sound/xen/xen_snd_front_cfg.c
> @@ -0,0 +1,517 @@
> +// SPDX-License-Identifier: GPL-2.0 OR MIT
> +
> +/*
> + * Xen para-virtual sound device
> + *
> + * Copyright (C) 2016-2018 EPAM Systems Inc.
> + *
> + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> + */
> +
> +#include <xen/xenbus.h>
> +
> +#include <xen/interface/io/sndif.h>
> +
> +#include "xen_snd_front.h"
> +#include "xen_snd_front_cfg.h"
> +
> +/* maximum number of supported streams */
Comment style (multiple times below, too):
Start with a capital letter and end sentences with a full stop.
> +#define VSND_MAX_STREAM 8
> +
> +struct cfg_hw_sample_rate {
> + const char *name;
> + unsigned int mask;
> + unsigned int value;
> +};
> +
> +static const struct cfg_hw_sample_rate CFG_HW_SUPPORTED_RATES[] = {
> + { .name = "5512", .mask = SNDRV_PCM_RATE_5512, .value = 5512 },
> + { .name = "8000", .mask = SNDRV_PCM_RATE_8000, .value = 8000 },
> + { .name = "11025", .mask = SNDRV_PCM_RATE_11025, .value = 11025 },
> + { .name = "16000", .mask = SNDRV_PCM_RATE_16000, .value = 16000 },
> + { .name = "22050", .mask = SNDRV_PCM_RATE_22050, .value = 22050 },
> + { .name = "32000", .mask = SNDRV_PCM_RATE_32000, .value = 32000 },
> + { .name = "44100", .mask = SNDRV_PCM_RATE_44100, .value = 44100 },
> + { .name = "48000", .mask = SNDRV_PCM_RATE_48000, .value = 48000 },
> + { .name = "64000", .mask = SNDRV_PCM_RATE_64000, .value = 64000 },
> + { .name = "96000", .mask = SNDRV_PCM_RATE_96000, .value = 96000 },
> + { .name = "176400", .mask = SNDRV_PCM_RATE_176400, .value = 176400 },
> + { .name = "192000", .mask = SNDRV_PCM_RATE_192000, .value = 192000 },
> +};
> +
> +struct cfg_hw_sample_format {
> + const char *name;
> + u64 mask;
> +};
> +
> +static const struct cfg_hw_sample_format CFG_HW_SUPPORTED_FORMATS[] = {
> + {
> + .name = XENSND_PCM_FORMAT_U8_STR,
> + .mask = SNDRV_PCM_FMTBIT_U8
> + },
> + {
> + .name = XENSND_PCM_FORMAT_S8_STR,
> + .mask = SNDRV_PCM_FMTBIT_S8
> + },
> + {
> + .name = XENSND_PCM_FORMAT_U16_LE_STR,
> + .mask = SNDRV_PCM_FMTBIT_U16_LE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_U16_BE_STR,
> + .mask = SNDRV_PCM_FMTBIT_U16_BE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_S16_LE_STR,
> + .mask = SNDRV_PCM_FMTBIT_S16_LE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_S16_BE_STR,
> + .mask = SNDRV_PCM_FMTBIT_S16_BE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_U24_LE_STR,
> + .mask = SNDRV_PCM_FMTBIT_U24_LE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_U24_BE_STR,
> + .mask = SNDRV_PCM_FMTBIT_U24_BE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_S24_LE_STR,
> + .mask = SNDRV_PCM_FMTBIT_S24_LE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_S24_BE_STR,
> + .mask = SNDRV_PCM_FMTBIT_S24_BE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_U32_LE_STR,
> + .mask = SNDRV_PCM_FMTBIT_U32_LE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_U32_BE_STR,
> + .mask = SNDRV_PCM_FMTBIT_U32_BE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_S32_LE_STR,
> + .mask = SNDRV_PCM_FMTBIT_S32_LE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_S32_BE_STR,
> + .mask = SNDRV_PCM_FMTBIT_S32_BE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_A_LAW_STR,
> + .mask = SNDRV_PCM_FMTBIT_A_LAW
> + },
> + {
> + .name = XENSND_PCM_FORMAT_MU_LAW_STR,
> + .mask = SNDRV_PCM_FMTBIT_MU_LAW
> + },
> + {
> + .name = XENSND_PCM_FORMAT_F32_LE_STR,
> + .mask = SNDRV_PCM_FMTBIT_FLOAT_LE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_F32_BE_STR,
> + .mask = SNDRV_PCM_FMTBIT_FLOAT_BE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_F64_LE_STR,
> + .mask = SNDRV_PCM_FMTBIT_FLOAT64_LE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_F64_BE_STR,
> + .mask = SNDRV_PCM_FMTBIT_FLOAT64_BE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE_STR,
> + .mask = SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE_STR,
> + .mask = SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_BE
> + },
> + {
> + .name = XENSND_PCM_FORMAT_IMA_ADPCM_STR,
> + .mask = SNDRV_PCM_FMTBIT_IMA_ADPCM
> + },
> + {
> + .name = XENSND_PCM_FORMAT_MPEG_STR,
> + .mask = SNDRV_PCM_FMTBIT_MPEG
> + },
> + {
> + .name = XENSND_PCM_FORMAT_GSM_STR,
> + .mask = SNDRV_PCM_FMTBIT_GSM
> + },
> +};
> +
> +static void cfg_hw_rates(char *list, unsigned int len,
> + const char *path, struct snd_pcm_hardware *pcm_hw)
> +{
> + char *cur_rate;
> + unsigned int cur_mask;
> + unsigned int cur_value;
> + unsigned int rates;
> + unsigned int rate_min;
> + unsigned int rate_max;
> + int i;
> +
> + rates = 0;
> + rate_min = -1;
> + rate_max = 0;
> + while ((cur_rate = strsep(&list, XENSND_LIST_SEPARATOR))) {
> + for (i = 0; i < ARRAY_SIZE(CFG_HW_SUPPORTED_RATES); i++)
> + if (!strncasecmp(cur_rate,
> + CFG_HW_SUPPORTED_RATES[i].name,
> + XENSND_SAMPLE_RATE_MAX_LEN)) {
> + cur_mask = CFG_HW_SUPPORTED_RATES[i].mask;
> + cur_value = CFG_HW_SUPPORTED_RATES[i].value;
> + rates |= cur_mask;
> + if (rate_min > cur_value)
> + rate_min = cur_value;
> + if (rate_max < cur_value)
> + rate_max = cur_value;
> + }
> + }
> +
> + if (rates) {
> + pcm_hw->rates = rates;
> + pcm_hw->rate_min = rate_min;
> + pcm_hw->rate_max = rate_max;
> + }
> +}
> +
> +static void cfg_formats(char *list, unsigned int len,
> + const char *path, struct snd_pcm_hardware *pcm_hw)
> +{
> + u64 formats;
> + char *cur_format;
> + int i;
> +
> + formats = 0;
> + while ((cur_format = strsep(&list, XENSND_LIST_SEPARATOR))) {
> + for (i = 0; i < ARRAY_SIZE(CFG_HW_SUPPORTED_FORMATS); i++)
> + if (!strncasecmp(cur_format,
> + CFG_HW_SUPPORTED_FORMATS[i].name,
> + XENSND_SAMPLE_FORMAT_MAX_LEN))
> + formats |= CFG_HW_SUPPORTED_FORMATS[i].mask;
> + }
> +
> + if (formats)
> + pcm_hw->formats = formats;
> +}
> +
> +#define MAX_BUFFER_SIZE (64 * 1024)
> +#define MIN_PERIOD_SIZE 64
> +#define MAX_PERIOD_SIZE MAX_BUFFER_SIZE
> +#define USE_FORMATS (SNDRV_PCM_FMTBIT_U8 | \
> + SNDRV_PCM_FMTBIT_S16_LE)
> +#define USE_RATE (SNDRV_PCM_RATE_CONTINUOUS | \
> + SNDRV_PCM_RATE_8000_48000)
> +#define USE_RATE_MIN 5512
> +#define USE_RATE_MAX 48000
> +#define USE_CHANNELS_MIN 1
> +#define USE_CHANNELS_MAX 2
> +#define USE_PERIODS_MIN 2
> +#define USE_PERIODS_MAX (MAX_BUFFER_SIZE / MIN_PERIOD_SIZE)
> +
> +static const struct snd_pcm_hardware SND_DRV_PCM_HW_DEFAULT = {
> + .info = (SNDRV_PCM_INFO_MMAP |
> + SNDRV_PCM_INFO_INTERLEAVED |
> + SNDRV_PCM_INFO_RESUME |
> + SNDRV_PCM_INFO_MMAP_VALID),
> + .formats = USE_FORMATS,
> + .rates = USE_RATE,
> + .rate_min = USE_RATE_MIN,
> + .rate_max = USE_RATE_MAX,
> + .channels_min = USE_CHANNELS_MIN,
> + .channels_max = USE_CHANNELS_MAX,
> + .buffer_bytes_max = MAX_BUFFER_SIZE,
> + .period_bytes_min = MIN_PERIOD_SIZE,
> + .period_bytes_max = MAX_PERIOD_SIZE,
> + .periods_min = USE_PERIODS_MIN,
> + .periods_max = USE_PERIODS_MAX,
> + .fifo_size = 0,
> +};
> +
> +static void cfg_read_pcm_hw(const char *path,
> + struct snd_pcm_hardware *parent_pcm_hw,
> + struct snd_pcm_hardware *pcm_hw)
> +{
> + char *list;
> + int val;
> + size_t buf_sz;
> + unsigned int len;
> +
> + /* inherit parent's PCM HW and read overrides from XenStore */
> + if (parent_pcm_hw)
> + *pcm_hw = *parent_pcm_hw;
> + else
> + *pcm_hw = SND_DRV_PCM_HW_DEFAULT;
> +
> + val = xenbus_read_unsigned(path, XENSND_FIELD_CHANNELS_MIN, 0);
> + if (val)
> + pcm_hw->channels_min = val;
> +
> + val = xenbus_read_unsigned(path, XENSND_FIELD_CHANNELS_MAX, 0);
> + if (val)
> + pcm_hw->channels_max = val;
> +
> + list = xenbus_read(XBT_NIL, path, XENSND_FIELD_SAMPLE_RATES, &len);
> + if (!IS_ERR(list)) {
> + cfg_hw_rates(list, len, path, pcm_hw);
> + kfree(list);
> + }
> +
> + list = xenbus_read(XBT_NIL, path, XENSND_FIELD_SAMPLE_FORMATS, &len);
> + if (!IS_ERR(list)) {
> + cfg_formats(list, len, path, pcm_hw);
> + kfree(list);
> + }
> +
> + buf_sz = xenbus_read_unsigned(path, XENSND_FIELD_BUFFER_SIZE, 0);
> + if (buf_sz)
> + pcm_hw->buffer_bytes_max = buf_sz;
> +
> + /* update configuration to match new values */
> + if (pcm_hw->channels_min > pcm_hw->channels_max)
> + pcm_hw->channels_min = pcm_hw->channels_max;
> +
> + if (pcm_hw->rate_min > pcm_hw->rate_max)
> + pcm_hw->rate_min = pcm_hw->rate_max;
> +
> + pcm_hw->period_bytes_max = pcm_hw->buffer_bytes_max;
> +
> + pcm_hw->periods_max = pcm_hw->period_bytes_max /
> + pcm_hw->period_bytes_min;
> +}
> +
> +static int cfg_get_stream_type(const char *path, int index,
> + int *num_pb, int *num_cap)
> +{
> + char *str = NULL;
> + char *stream_path;
> + int ret;
> +
> + *num_pb = 0;
> + *num_cap = 0;
> + stream_path = kasprintf(GFP_KERNEL, "%s/%d", path, index);
> + if (!stream_path) {
> + ret = -ENOMEM;
> + goto fail;
> + }
> +
> + str = xenbus_read(XBT_NIL, stream_path, XENSND_FIELD_TYPE, NULL);
> + if (IS_ERR(str)) {
> + ret = -EINVAL;
Is this correct? Do you want to return -EINVAL in case xenbus_read()
failed with e.g. -ENOMEM?
> + goto fail;
> + }
> +
> + if (!strncasecmp(str, XENSND_STREAM_TYPE_PLAYBACK,
> + sizeof(XENSND_STREAM_TYPE_PLAYBACK))) {
> + (*num_pb)++;
> + } else if (!strncasecmp(str, XENSND_STREAM_TYPE_CAPTURE,
> + sizeof(XENSND_STREAM_TYPE_CAPTURE))) {
> + (*num_cap)++;
> + } else {
> + ret = -EINVAL;
> + goto fail;
> + }
> + ret = 0;
> +
> +fail:
> + kfree(stream_path);
> + kfree(str);
> + return ret;
> +}
> +
> +static int cfg_stream(struct xen_snd_front_info *front_info,
> + struct xen_front_cfg_pcm_instance *pcm_instance,
> + const char *path, int index, int *cur_pb, int *cur_cap,
> + int *stream_cnt)
> +{
> + char *str = NULL;
> + char *stream_path;
> + struct xen_front_cfg_stream *stream;
> + int ret;
> +
> + stream_path = devm_kasprintf(&front_info->xb_dev->dev,
> + GFP_KERNEL, "%s/%d", path, index);
> + if (!stream_path) {
> + ret = -ENOMEM;
> + goto fail;
> + }
> +
> + str = xenbus_read(XBT_NIL, stream_path, XENSND_FIELD_TYPE, NULL);
> + if (IS_ERR(str)) {
> + ret = -EINVAL;
Same as above.
> + goto fail;
> + }
> +
> + if (!strncasecmp(str, XENSND_STREAM_TYPE_PLAYBACK,
> + sizeof(XENSND_STREAM_TYPE_PLAYBACK))) {
> + stream = &pcm_instance->streams_pb[(*cur_pb)++];
> + } else if (!strncasecmp(str, XENSND_STREAM_TYPE_CAPTURE,
> + sizeof(XENSND_STREAM_TYPE_CAPTURE))) {
> + stream = &pcm_instance->streams_cap[(*cur_cap)++];
> + } else {
> + ret = -EINVAL;
> + goto fail;
> + }
Until here this function looks very much like cfg_get_stream_type().
Can't they use a common sub-function?
> +
> + /* get next stream index */
> + stream->index = (*stream_cnt)++;
> + stream->xenstore_path = stream_path;
> + /*
> + * check in Xen store if PCM HW configuration exists for this stream
> + * and update if so, e.g. we inherit all values from device's PCM HW,
> + * but can still override some of the values for the stream
> + */
> + cfg_read_pcm_hw(stream->xenstore_path,
> + &pcm_instance->pcm_hw, &stream->pcm_hw);
> + ret = 0;
> +
> +fail:
> + kfree(str);
> + return ret;
> +}
> +
> +static int cfg_device(struct xen_snd_front_info *front_info,
> + struct xen_front_cfg_pcm_instance *pcm_instance,
> + struct snd_pcm_hardware *parent_pcm_hw,
> + const char *path, int node_index, int *stream_cnt)
> +{
> + char *str;
> + char *device_path;
> + int ret, i, num_streams;
> + int num_pb, num_cap;
> + int cur_pb, cur_cap;
> + char node[3];
> +
> + device_path = kasprintf(GFP_KERNEL, "%s/%d", path, node_index);
> + if (!device_path)
> + return -ENOMEM;
> +
> + str = xenbus_read(XBT_NIL, device_path, XENSND_FIELD_DEVICE_NAME, NULL);
> + if (!IS_ERR(str)) {
> + strncpy(pcm_instance->name, str, sizeof(pcm_instance->name));
> + kfree(str);
> + }
> +
> + pcm_instance->device_id = node_index;
> +
> + /*
> + * check in Xen store if PCM HW configuration exists for this device
> + * and update if so, e.g. we inherit all values from card's PCM HW,
> + * but can still override some of the values for the device
> + */
> + cfg_read_pcm_hw(device_path, parent_pcm_hw, &pcm_instance->pcm_hw);
> +
> + /* find out how many streams were configured in Xen store */
> + num_streams = 0;
> + do {
> + snprintf(node, sizeof(node), "%d", num_streams);
> + if (!xenbus_exists(XBT_NIL, device_path, node))
> + break;
> +
> + num_streams++;
> + } while (num_streams < VSND_MAX_STREAM);
> +
> + pcm_instance->num_streams_pb = 0;
> + pcm_instance->num_streams_cap = 0;
> + /* get number of playback and capture streams */
> + for (i = 0; i < num_streams; i++) {
> + ret = cfg_get_stream_type(device_path, i, &num_pb, &num_cap);
> + if (ret < 0)
> + goto fail;
> +
> + pcm_instance->num_streams_pb += num_pb;
> + pcm_instance->num_streams_cap += num_cap;
> + }
> +
> + if (pcm_instance->num_streams_pb) {
> + pcm_instance->streams_pb =
> + devm_kcalloc(&front_info->xb_dev->dev,
> + pcm_instance->num_streams_pb,
> + sizeof(struct xen_front_cfg_stream),
> + GFP_KERNEL);
> + if (!pcm_instance->streams_pb) {
> + ret = -ENOMEM;
> + goto fail;
> + }
> + }
> +
> + if (pcm_instance->num_streams_cap) {
> + pcm_instance->streams_cap =
> + devm_kcalloc(&front_info->xb_dev->dev,
> + pcm_instance->num_streams_cap,
> + sizeof(struct xen_front_cfg_stream),
> + GFP_KERNEL);
> + if (!pcm_instance->streams_cap) {
> + ret = -ENOMEM;
> + goto fail;
> + }
> + }
> +
> + cur_pb = 0;
> + cur_cap = 0;
> + for (i = 0; i < num_streams; i++) {
> + ret = cfg_stream(front_info, pcm_instance, device_path, i,
> + &cur_pb, &cur_cap, stream_cnt);
> + if (ret < 0)
> + goto fail;
> + }
> + ret = 0;
> +
> +fail:
> + kfree(device_path);
> + return ret;
> +}
> +
> +int xen_snd_front_cfg_card(struct xen_snd_front_info *front_info,
> + int *stream_cnt)
> +{
> + struct xenbus_device *xb_dev = front_info->xb_dev;
> + struct xen_front_cfg_card *cfg = &front_info->cfg;
> + int ret, num_devices, i;
> + char node[3];
> +
> + *stream_cnt = 0;
> + num_devices = 0;
> + do {
> + snprintf(node, sizeof(node), "%d", num_devices);
> + if (!xenbus_exists(XBT_NIL, xb_dev->nodename, node))
> + break;
> +
> + num_devices++;
> + } while (num_devices < SNDRV_PCM_DEVICES);
> +
> + if (!num_devices) {
> + dev_warn(&xb_dev->dev,
> + "No devices configured for sound card at %s\n",
> + xb_dev->nodename);
> + return -ENODEV;
> + }
> +
> + /* start from default PCM HW configuration for the card */
> + cfg_read_pcm_hw(xb_dev->nodename, NULL, &cfg->pcm_hw);
> +
> + cfg->pcm_instances =
> + devm_kcalloc(&front_info->xb_dev->dev, num_devices,
> + sizeof(struct xen_front_cfg_pcm_instance),
> + GFP_KERNEL);
> + if (!cfg->pcm_instances)
> + return -ENOMEM;
> +
> + for (i = 0; i < num_devices; i++) {
> + ret = cfg_device(front_info, &cfg->pcm_instances[i],
> + &cfg->pcm_hw, xb_dev->nodename, i, stream_cnt);
> + if (ret < 0)
> + return ret;
Who will free all the memory allocated until now in case of an error?
And I think when removing the device freeing the memory is missing, too.
Juergen
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling
2018-04-16 6:24 ` [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling Oleksandr Andrushchenko
@ 2018-04-16 13:12 ` Juergen Gross
2018-04-17 8:58 ` Oleksandr Andrushchenko
2018-04-16 13:53 ` kbuild test robot
2018-04-24 14:20 ` Takashi Iwai
2 siblings, 1 reply; 40+ messages in thread
From: Juergen Gross @ 2018-04-16 13:12 UTC (permalink / raw)
To: Oleksandr Andrushchenko, xen-devel, linux-kernel, alsa-devel,
boris.ostrovsky, konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>
> Handle Xen event channels:
> - create for all configured streams and publish
> corresponding ring references and event channels in Xen store,
> so backend can connect
> - implement event channels interrupt handlers
> - create and destroy event channels with respect to Xen bus state
>
> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> ---
> sound/xen/Makefile | 3 +-
> sound/xen/xen_snd_front.c | 10 +-
> sound/xen/xen_snd_front.h | 7 +
> sound/xen/xen_snd_front_evtchnl.c | 474 ++++++++++++++++++++++++++++++++++++++
> sound/xen/xen_snd_front_evtchnl.h | 92 ++++++++
> 5 files changed, 584 insertions(+), 2 deletions(-)
> create mode 100644 sound/xen/xen_snd_front_evtchnl.c
> create mode 100644 sound/xen/xen_snd_front_evtchnl.h
>
> diff --git a/sound/xen/Makefile b/sound/xen/Makefile
> index 06705bef61fa..03c669984000 100644
> --- a/sound/xen/Makefile
> +++ b/sound/xen/Makefile
> @@ -1,6 +1,7 @@
> # SPDX-License-Identifier: GPL-2.0 OR MIT
>
> snd_xen_front-objs := xen_snd_front.o \
> - xen_snd_front_cfg.o
> + xen_snd_front_cfg.o \
> + xen_snd_front_evtchnl.o
>
> obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
> diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
> index 65d2494a9d14..eb46bf4070f9 100644
> --- a/sound/xen/xen_snd_front.c
> +++ b/sound/xen/xen_snd_front.c
> @@ -18,9 +18,11 @@
> #include <xen/interface/io/sndif.h>
>
> #include "xen_snd_front.h"
> +#include "xen_snd_front_evtchnl.h"
Does it really make sense to have multiple driver-private headers?
I think those can be merged.
>
> static void xen_snd_drv_fini(struct xen_snd_front_info *front_info)
> {
> + xen_snd_front_evtchnl_free_all(front_info);
> }
>
> static int sndback_initwait(struct xen_snd_front_info *front_info)
> @@ -32,7 +34,12 @@ static int sndback_initwait(struct xen_snd_front_info *front_info)
> if (ret < 0)
> return ret;
>
> - return 0;
> + /* create event channels for all streams and publish */
> + ret = xen_snd_front_evtchnl_create_all(front_info, num_streams);
> + if (ret < 0)
> + return ret;
> +
> + return xen_snd_front_evtchnl_publish_all(front_info);
> }
>
> static int sndback_connect(struct xen_snd_front_info *front_info)
> @@ -122,6 +129,7 @@ static int xen_drv_probe(struct xenbus_device *xb_dev,
> return -ENOMEM;
>
> front_info->xb_dev = xb_dev;
> + spin_lock_init(&front_info->io_lock);
> dev_set_drvdata(&xb_dev->dev, front_info);
>
> return xenbus_switch_state(xb_dev, XenbusStateInitialising);
> diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
> index b52226cb30bc..9c2ffbb4e4b8 100644
> --- a/sound/xen/xen_snd_front.h
> +++ b/sound/xen/xen_snd_front.h
> @@ -13,9 +13,16 @@
>
> #include "xen_snd_front_cfg.h"
>
> +struct xen_snd_front_evtchnl_pair;
> +
> struct xen_snd_front_info {
> struct xenbus_device *xb_dev;
>
> + /* serializer for backend IO: request/response */
> + spinlock_t io_lock;
> + int num_evt_pairs;
> + struct xen_snd_front_evtchnl_pair *evt_pairs;
> +
> struct xen_front_cfg_card cfg;
> };
>
> diff --git a/sound/xen/xen_snd_front_evtchnl.c b/sound/xen/xen_snd_front_evtchnl.c
> new file mode 100644
> index 000000000000..9ece39f938f8
> --- /dev/null
> +++ b/sound/xen/xen_snd_front_evtchnl.c
> @@ -0,0 +1,474 @@
> +// SPDX-License-Identifier: GPL-2.0 OR MIT
> +
> +/*
> + * Xen para-virtual sound device
> + *
> + * Copyright (C) 2016-2018 EPAM Systems Inc.
> + *
> + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> + */
> +
> +#include <xen/events.h>
> +#include <xen/grant_table.h>
> +#include <xen/xen.h>
> +#include <xen/xenbus.h>
> +
> +#include "xen_snd_front.h"
> +#include "xen_snd_front_cfg.h"
> +#include "xen_snd_front_evtchnl.h"
> +
> +static irqreturn_t evtchnl_interrupt_req(int irq, void *dev_id)
> +{
> + struct xen_snd_front_evtchnl *channel = dev_id;
> + struct xen_snd_front_info *front_info = channel->front_info;
> + struct xensnd_resp *resp;
> + RING_IDX i, rp;
> + unsigned long flags;
> +
> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
> + return IRQ_HANDLED;
> +
> + spin_lock_irqsave(&front_info->io_lock, flags);
> +
> +again:
> + rp = channel->u.req.ring.sring->rsp_prod;
> + /* ensure we see queued responses up to rp */
> + rmb();
> +
> + for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
> + resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
> + if (resp->id != channel->evt_id)
> + continue;
> + switch (resp->operation) {
> + case XENSND_OP_OPEN:
> + /* fall through */
> + case XENSND_OP_CLOSE:
> + /* fall through */
> + case XENSND_OP_READ:
> + /* fall through */
> + case XENSND_OP_WRITE:
> + /* fall through */
> + case XENSND_OP_TRIGGER:
> + channel->u.req.resp_status = resp->status;
> + complete(&channel->u.req.completion);
> + break;
> + case XENSND_OP_HW_PARAM_QUERY:
> + channel->u.req.resp_status = resp->status;
> + channel->u.req.resp.hw_param =
> + resp->resp.hw_param;
> + complete(&channel->u.req.completion);
> + break;
> +
> + default:
> + dev_err(&front_info->xb_dev->dev,
> + "Operation %d is not supported\n",
> + resp->operation);
> + break;
> + }
> + }
> +
> + channel->u.req.ring.rsp_cons = i;
> + if (i != channel->u.req.ring.req_prod_pvt) {
> + int more_to_do;
> +
> + RING_FINAL_CHECK_FOR_RESPONSES(&channel->u.req.ring,
> + more_to_do);
> + if (more_to_do)
> + goto again;
> + } else {
> + channel->u.req.ring.sring->rsp_event = i + 1;
> + }
> +
> + spin_unlock_irqrestore(&front_info->io_lock, flags);
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t evtchnl_interrupt_evt(int irq, void *dev_id)
> +{
> + struct xen_snd_front_evtchnl *channel = dev_id;
> + struct xen_snd_front_info *front_info = channel->front_info;
> + struct xensnd_event_page *page = channel->u.evt.page;
> + u32 cons, prod;
> + unsigned long flags;
> +
> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
> + return IRQ_HANDLED;
> +
> + spin_lock_irqsave(&front_info->io_lock, flags);
> +
> + prod = page->in_prod;
> + /* ensure we see ring contents up to prod */
> + virt_rmb();
> + if (prod == page->in_cons)
> + goto out;
> +
> + for (cons = page->in_cons; cons != prod; cons++) {
> + struct xensnd_evt *event;
> +
> + event = &XENSND_IN_RING_REF(page, cons);
> + if (unlikely(event->id != channel->evt_id++))
> + continue;
> +
> + switch (event->type) {
> + case XENSND_EVT_CUR_POS:
> + /* do nothing at the moment */
> + break;
> + }
> + }
> +
> + page->in_cons = cons;
> + /* ensure ring contents */
> + virt_wmb();
> +
> +out:
> + spin_unlock_irqrestore(&front_info->io_lock, flags);
> + return IRQ_HANDLED;
> +}
> +
> +void xen_snd_front_evtchnl_flush(struct xen_snd_front_evtchnl *channel)
> +{
> + int notify;
> +
> + channel->u.req.ring.req_prod_pvt++;
> + RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&channel->u.req.ring, notify);
> + if (notify)
> + notify_remote_via_irq(channel->irq);
> +}
> +
> +static void evtchnl_free(struct xen_snd_front_info *front_info,
> + struct xen_snd_front_evtchnl *channel)
> +{
> + unsigned long page = 0;
> +
> + if (channel->type == EVTCHNL_TYPE_REQ)
> + page = (unsigned long)channel->u.req.ring.sring;
> + else if (channel->type == EVTCHNL_TYPE_EVT)
> + page = (unsigned long)channel->u.evt.page;
> +
> + if (!page)
> + return;
> +
> + channel->state = EVTCHNL_STATE_DISCONNECTED;
> + if (channel->type == EVTCHNL_TYPE_REQ) {
> + /* release all who still waits for response if any */
> + channel->u.req.resp_status = -EIO;
> + complete_all(&channel->u.req.completion);
> + }
> +
> + if (channel->irq)
> + unbind_from_irqhandler(channel->irq, channel);
> +
> + if (channel->port)
> + xenbus_free_evtchn(front_info->xb_dev, channel->port);
> +
> + /* end access and free the page */
> + if (channel->gref != GRANT_INVALID_REF)
> + gnttab_end_foreign_access(channel->gref, 0, page);
Free page?
> +
> + memset(channel, 0, sizeof(*channel));
> +}
> +
> +void xen_snd_front_evtchnl_free_all(struct xen_snd_front_info *front_info)
> +{
> + int i;
> +
> + if (!front_info->evt_pairs)
> + return;
> +
> + for (i = 0; i < front_info->num_evt_pairs; i++) {
> + evtchnl_free(front_info, &front_info->evt_pairs[i].req);
> + evtchnl_free(front_info, &front_info->evt_pairs[i].evt);
> + }
> +
> + kfree(front_info->evt_pairs);
> + front_info->evt_pairs = NULL;
> +}
> +
> +static int evtchnl_alloc(struct xen_snd_front_info *front_info, int index,
> + struct xen_snd_front_evtchnl *channel,
> + enum xen_snd_front_evtchnl_type type)
> +{
> + struct xenbus_device *xb_dev = front_info->xb_dev;
> + unsigned long page;
> + grant_ref_t gref;
> + irq_handler_t handler;
> + char *handler_name = NULL;
> + int ret;
> +
> + memset(channel, 0, sizeof(*channel));
> + channel->type = type;
> + channel->index = index;
> + channel->front_info = front_info;
> + channel->state = EVTCHNL_STATE_DISCONNECTED;
> + channel->gref = GRANT_INVALID_REF;
> + page = get_zeroed_page(GFP_NOIO | __GFP_HIGH);
Why GFP_NOIO | __GFP_HIGH? Could it be you copied that from blkfront
driver? I believe swapping via sound card is rather uncommon.
> + if (!page) {
> + ret = -ENOMEM;
> + goto fail;
> + }
> +
> + handler_name = kasprintf(GFP_KERNEL, "%s-%s", XENSND_DRIVER_NAME,
> + type == EVTCHNL_TYPE_REQ ?
> + XENSND_FIELD_RING_REF :
> + XENSND_FIELD_EVT_RING_REF);
> + if (!handler_name) {
> + ret = -ENOMEM;
Missing free_page(page)? Maybe you rather add it in the common
fail path instead of the numerous instances below?
Juergen
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 4/5] ALSA: xen-front: Implement handling of shared buffers
2018-04-16 6:24 ` [PATCH v2 4/5] ALSA: xen-front: Implement handling of shared buffers Oleksandr Andrushchenko
@ 2018-04-16 13:39 ` Juergen Gross
2018-04-17 9:22 ` Oleksandr Andrushchenko
0 siblings, 1 reply; 40+ messages in thread
From: Juergen Gross @ 2018-04-16 13:39 UTC (permalink / raw)
To: Oleksandr Andrushchenko, xen-devel, linux-kernel, alsa-devel,
boris.ostrovsky, konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>
> Implement shared buffer handling according to the
> para-virtualized sound device protocol at xen/interface/io/sndif.h:
> - manage buffer memory
> - handle granted references
> - handle page directories
>
> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> ---
> sound/xen/Makefile | 3 +-
> sound/xen/xen_snd_front.c | 8 ++
> sound/xen/xen_snd_front_shbuf.c | 193 ++++++++++++++++++++++++++++++++++++++++
> sound/xen/xen_snd_front_shbuf.h | 36 ++++++++
> 4 files changed, 239 insertions(+), 1 deletion(-)
> create mode 100644 sound/xen/xen_snd_front_shbuf.c
> create mode 100644 sound/xen/xen_snd_front_shbuf.h
>
> diff --git a/sound/xen/Makefile b/sound/xen/Makefile
> index 03c669984000..f028bc30af5d 100644
> --- a/sound/xen/Makefile
> +++ b/sound/xen/Makefile
> @@ -2,6 +2,7 @@
>
> snd_xen_front-objs := xen_snd_front.o \
> xen_snd_front_cfg.o \
> - xen_snd_front_evtchnl.o
> + xen_snd_front_evtchnl.o \
> + xen_snd_front_shbuf.o
>
> obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
> diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
> index eb46bf4070f9..0569c6c596a3 100644
> --- a/sound/xen/xen_snd_front.c
> +++ b/sound/xen/xen_snd_front.c
> @@ -11,6 +11,7 @@
> #include <linux/delay.h>
> #include <linux/module.h>
>
> +#include <xen/page.h>
> #include <xen/platform_pci.h>
> #include <xen/xen.h>
> #include <xen/xenbus.h>
> @@ -186,6 +187,13 @@ static struct xenbus_driver xen_driver = {
>
> static int __init xen_drv_init(void)
> {
> + /* At the moment we only support case with XEN_PAGE_SIZE == PAGE_SIZE */
> + if (XEN_PAGE_SIZE != PAGE_SIZE) {
> + pr_err(XENSND_DRIVER_NAME ": different kernel and Xen page sizes are not supported: XEN_PAGE_SIZE (%lu) != PAGE_SIZE (%lu)\n",
> + XEN_PAGE_SIZE, PAGE_SIZE);
> + return -ENODEV;
> + }
Do you really want to print that error message on bare metal?
> +
> if (!xen_domain())
> return -ENODEV;
>
> diff --git a/sound/xen/xen_snd_front_shbuf.c b/sound/xen/xen_snd_front_shbuf.c
> new file mode 100644
> index 000000000000..6845dbc7fdf5
> --- /dev/null
> +++ b/sound/xen/xen_snd_front_shbuf.c
> @@ -0,0 +1,193 @@
> +// SPDX-License-Identifier: GPL-2.0 OR MIT
> +
> +/*
> + * Xen para-virtual sound device
> + *
> + * Copyright (C) 2016-2018 EPAM Systems Inc.
> + *
> + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> + */
> +
> +#include <xen/xen.h>
> +#include <xen/xenbus.h>
> +
> +#include "xen_snd_front_shbuf.h"
> +
> +grant_ref_t xen_snd_front_shbuf_get_dir_start(struct xen_snd_front_shbuf *buf)
> +{
> + if (!buf->grefs)
> + return GRANT_INVALID_REF;
> +
> + return buf->grefs[0];
> +}
> +
> +void xen_snd_front_shbuf_clear(struct xen_snd_front_shbuf *buf)
> +{
> + memset(buf, 0, sizeof(*buf));
> +}
> +
> +void xen_snd_front_shbuf_free(struct xen_snd_front_shbuf *buf)
> +{
> + int i;
> +
> + if (buf->grefs) {
> + for (i = 0; i < buf->num_grefs; i++)
> + if (buf->grefs[i] != GRANT_INVALID_REF)
> + gnttab_end_foreign_access(buf->grefs[i],
> + 0, 0UL);
> + kfree(buf->grefs);
> + }
> + kfree(buf->directory);
> + free_pages_exact(buf->buffer, buf->buffer_sz);
> + xen_snd_front_shbuf_clear(buf);
> +}
> +
> +/*
> + * number of grant references a page can hold with respect to the
> + * xensnd_page_directory header
> + */
> +#define XENSND_NUM_GREFS_PER_PAGE ((XEN_PAGE_SIZE - \
> + offsetof(struct xensnd_page_directory, gref)) / \
> + sizeof(grant_ref_t))
> +
> +static void fill_page_dir(struct xen_snd_front_shbuf *buf,
> + int num_pages_dir)
> +{
> + struct xensnd_page_directory *page_dir;
> + unsigned char *ptr;
> + int i, cur_gref, grefs_left, to_copy;
> +
> + ptr = buf->directory;
> + grefs_left = buf->num_grefs - num_pages_dir;
> + /*
> + * skip grant references at the beginning, they are for pages granted
> + * for the page directory itself
> + */
> + cur_gref = num_pages_dir;
> + for (i = 0; i < num_pages_dir; i++) {
> + page_dir = (struct xensnd_page_directory *)ptr;
> + if (grefs_left <= XENSND_NUM_GREFS_PER_PAGE) {
> + to_copy = grefs_left;
> + page_dir->gref_dir_next_page = GRANT_INVALID_REF;
> + } else {
> + to_copy = XENSND_NUM_GREFS_PER_PAGE;
> + page_dir->gref_dir_next_page = buf->grefs[i + 1];
> + }
> +
> + memcpy(&page_dir->gref, &buf->grefs[cur_gref],
> + to_copy * sizeof(grant_ref_t));
> +
> + ptr += XEN_PAGE_SIZE;
> + grefs_left -= to_copy;
> + cur_gref += to_copy;
> + }
> +}
> +
> +static int grant_references(struct xenbus_device *xb_dev,
> + struct xen_snd_front_shbuf *buf,
> + int num_pages_dir, int num_pages_buffer,
> + int num_grefs)
> +{
> + grant_ref_t priv_gref_head;
> + unsigned long frame;
> + int ret, i, j, cur_ref;
> + int otherend_id;
> +
> + ret = gnttab_alloc_grant_references(num_grefs, &priv_gref_head);
> + if (ret)
> + return ret;
> +
> + buf->num_grefs = num_grefs;
> + otherend_id = xb_dev->otherend_id;
> + j = 0;
> +
> + for (i = 0; i < num_pages_dir; i++) {
> + cur_ref = gnttab_claim_grant_reference(&priv_gref_head);
> + if (cur_ref < 0) {
> + ret = cur_ref;
> + goto fail;
> + }
> +
> + frame = xen_page_to_gfn(virt_to_page(buf->directory +
> + XEN_PAGE_SIZE * i));
> + gnttab_grant_foreign_access_ref(cur_ref, otherend_id, frame, 0);
> + buf->grefs[j++] = cur_ref;
> + }
> +
> + for (i = 0; i < num_pages_buffer; i++) {
> + cur_ref = gnttab_claim_grant_reference(&priv_gref_head);
> + if (cur_ref < 0) {
> + ret = cur_ref;
> + goto fail;
> + }
> +
> + frame = xen_page_to_gfn(virt_to_page(buf->buffer +
> + XEN_PAGE_SIZE * i));
> + gnttab_grant_foreign_access_ref(cur_ref, otherend_id, frame, 0);
> + buf->grefs[j++] = cur_ref;
> + }
> +
> + gnttab_free_grant_references(priv_gref_head);
> + fill_page_dir(buf, num_pages_dir);
> + return 0;
> +
> +fail:
> + gnttab_free_grant_references(priv_gref_head);
> + return ret;
> +}
> +
> +static int alloc_int_buffers(struct xen_snd_front_shbuf *buf,
> + int num_pages_dir, int num_pages_buffer,
> + int num_grefs)
> +{
> + buf->grefs = kcalloc(num_grefs, sizeof(*buf->grefs), GFP_KERNEL);
> + if (!buf->grefs)
> + return -ENOMEM;
> +
> + buf->directory = kcalloc(num_pages_dir, XEN_PAGE_SIZE, GFP_KERNEL);
> + if (!buf->directory)
> + goto fail;
> +
> + buf->buffer_sz = num_pages_buffer * XEN_PAGE_SIZE;
> + buf->buffer = alloc_pages_exact(buf->buffer_sz, GFP_KERNEL);
> + if (!buf->buffer)
> + goto fail;
> +
> + return 0;
> +
> +fail:
> + kfree(buf->grefs);
> + buf->grefs = NULL;
> + kfree(buf->directory);
Why do you need to free those here? Shouldn't that be done via
xen_snd_front_shbuf_free() in case of an error?
Juergen
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling
2018-04-16 6:24 ` [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling Oleksandr Andrushchenko
2018-04-16 13:12 ` Juergen Gross
@ 2018-04-16 13:53 ` kbuild test robot
2018-04-24 14:20 ` Takashi Iwai
2 siblings, 0 replies; 40+ messages in thread
From: kbuild test robot @ 2018-04-16 13:53 UTC (permalink / raw)
To: Oleksandr Andrushchenko
Cc: kbuild-all, xen-devel, linux-kernel, alsa-devel, jgross,
boris.ostrovsky, konrad.wilk, perex, tiwai, andr2000,
Oleksandr Andrushchenko
[-- Attachment #1: Type: text/plain, Size: 13535 bytes --]
Hi Oleksandr,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on sound/for-next]
[also build test ERROR on v4.17-rc1 next-20180416]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Oleksandr-Andrushchenko/ALSA-xen-front-Add-Xen-para-virtualized-frontend-driver/20180416-143123
base: https://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound.git for-next
config: x86_64-allmodconfig (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
All errors (new ones prefixed by >>):
In file included from sound/xen/xen_snd_front.c:21:0:
>> sound/xen/xen_snd_front_evtchnl.h:62:34: error: field 'hw_param' has incomplete type
struct xensnd_query_hw_param hw_param;
^~~~~~~~
--
sound/xen/xen_snd_front_evtchnl.c:51:22: sparse: undefined identifier 'XENSND_OP_TRIGGER'
sound/xen/xen_snd_front_evtchnl.c:55:22: sparse: undefined identifier 'XENSND_OP_HW_PARAM_QUERY'
sound/xen/xen_snd_front_evtchnl.c:58:45: sparse: no member 'resp' in struct xensnd_resp
sound/xen/xen_snd_front_evtchnl.c:51:22: sparse: incompatible types for 'case' statement
sound/xen/xen_snd_front_evtchnl.c:55:22: sparse: incompatible types for 'case' statement
sound/xen/xen_snd_front_evtchnl.c:99:20: sparse: using member 'in_prod' in incomplete struct xensnd_event_page
sound/xen/xen_snd_front_evtchnl.c:102:25: sparse: using member 'in_cons' in incomplete struct xensnd_event_page
sound/xen/xen_snd_front_evtchnl.c:105:25: sparse: using member 'in_cons' in incomplete struct xensnd_event_page
sound/xen/xen_snd_front_evtchnl.c:108:26: sparse: undefined identifier 'XENSND_IN_RING_REF'
sound/xen/xen_snd_front_evtchnl.c:109:21: sparse: using member 'id' in incomplete struct xensnd_evt
sound/xen/xen_snd_front_evtchnl.c:112:30: sparse: using member 'type' in incomplete struct xensnd_evt
sound/xen/xen_snd_front_evtchnl.c:113:22: sparse: undefined identifier 'XENSND_EVT_CUR_POS'
sound/xen/xen_snd_front_evtchnl.c:113:22: sparse: incompatible types for 'case' statement
sound/xen/xen_snd_front_evtchnl.c:119:13: sparse: using member 'in_cons' in incomplete struct xensnd_event_page
sound/xen/xen_snd_front_evtchnl.c:213:34: sparse: undefined identifier 'XENSND_FIELD_EVT_RING_REF'
sound/xen/xen_snd_front_evtchnl.c:412:47: sparse: undefined identifier 'XENSND_FIELD_EVT_RING_REF'
sound/xen/xen_snd_front_evtchnl.c:432:47: sparse: undefined identifier 'XENSND_FIELD_EVT_RING_REF'
sound/xen/xen_snd_front_evtchnl.c:51:22: sparse: Expected constant expression in case statement
sound/xen/xen_snd_front_evtchnl.c:55:22: sparse: Expected constant expression in case statement
sound/xen/xen_snd_front_evtchnl.c:113:22: sparse: Expected constant expression in case statement
In file included from sound/xen/xen_snd_front_evtchnl.c:18:0:
>> sound/xen/xen_snd_front_evtchnl.h:62:34: error: field 'hw_param' has incomplete type
struct xensnd_query_hw_param hw_param;
^~~~~~~~
sound/xen/xen_snd_front_evtchnl.c: In function 'evtchnl_interrupt_req':
>> sound/xen/xen_snd_front_evtchnl.c:51:8: error: 'XENSND_OP_TRIGGER' undeclared (first use in this function); did you mean 'XENSND_OP_WRITE'?
case XENSND_OP_TRIGGER:
^~~~~~~~~~~~~~~~~
XENSND_OP_WRITE
sound/xen/xen_snd_front_evtchnl.c:51:8: note: each undeclared identifier is reported only once for each function it appears in
>> sound/xen/xen_snd_front_evtchnl.c:55:8: error: 'XENSND_OP_HW_PARAM_QUERY' undeclared (first use in this function); did you mean 'XENSND_OP_TRIGGER'?
case XENSND_OP_HW_PARAM_QUERY:
^~~~~~~~~~~~~~~~~~~~~~~~
XENSND_OP_TRIGGER
>> sound/xen/xen_snd_front_evtchnl.c:58:10: error: 'struct xensnd_resp' has no member named 'resp'
resp->resp.hw_param;
^~
sound/xen/xen_snd_front_evtchnl.c: In function 'evtchnl_interrupt_evt':
>> sound/xen/xen_snd_front_evtchnl.c:99:13: error: dereferencing pointer to incomplete type 'struct xensnd_event_page'
prod = page->in_prod;
^~
>> sound/xen/xen_snd_front_evtchnl.c:108:12: error: implicit declaration of function 'XENSND_IN_RING_REF'; did you mean 'XENSND_FIELD_RING_REF'? [-Werror=implicit-function-declaration]
event = &XENSND_IN_RING_REF(page, cons);
^~~~~~~~~~~~~~~~~~
XENSND_FIELD_RING_REF
>> sound/xen/xen_snd_front_evtchnl.c:108:11: error: lvalue required as unary '&' operand
event = &XENSND_IN_RING_REF(page, cons);
^
In file included from include/linux/kernel.h:10:0,
from include/linux/interrupt.h:6,
from include/xen/events.h:5,
from sound/xen/xen_snd_front_evtchnl.c:11:
>> sound/xen/xen_snd_front_evtchnl.c:109:21: error: dereferencing pointer to incomplete type 'struct xensnd_evt'
if (unlikely(event->id != channel->evt_id++))
^
include/linux/compiler.h:77:42: note: in definition of macro 'unlikely'
# define unlikely(x) __builtin_expect(!!(x), 0)
^
>> sound/xen/xen_snd_front_evtchnl.c:113:8: error: 'XENSND_EVT_CUR_POS' undeclared (first use in this function); did you mean 'XENSND_OP_CLOSE'?
case XENSND_EVT_CUR_POS:
^~~~~~~~~~~~~~~~~~
XENSND_OP_CLOSE
sound/xen/xen_snd_front_evtchnl.c: In function 'evtchnl_alloc':
>> sound/xen/xen_snd_front_evtchnl.c:213:6: error: 'XENSND_FIELD_EVT_RING_REF' undeclared (first use in this function); did you mean 'XENSND_FIELD_RING_REF'?
XENSND_FIELD_EVT_RING_REF);
^~~~~~~~~~~~~~~~~~~~~~~~~
XENSND_FIELD_RING_REF
sound/xen/xen_snd_front_evtchnl.c: In function 'xen_snd_front_evtchnl_publish_all':
sound/xen/xen_snd_front_evtchnl.c:412:12: error: 'XENSND_FIELD_EVT_RING_REF' undeclared (first use in this function); did you mean 'XENSND_FIELD_RING_REF'?
XENSND_FIELD_EVT_RING_REF,
^~~~~~~~~~~~~~~~~~~~~~~~~
XENSND_FIELD_RING_REF
>> sound/xen/xen_snd_front_evtchnl.c:413:12: error: 'XENSND_FIELD_EVT_EVT_CHNL' undeclared (first use in this function); did you mean 'XENSND_FIELD_EVT_CHNL'?
XENSND_FIELD_EVT_EVT_CHNL);
^~~~~~~~~~~~~~~~~~~~~~~~~
XENSND_FIELD_EVT_CHNL
cc1: some warnings being treated as errors
sparse warnings: (new ones prefixed by >>)
sound/xen/xen_snd_front_evtchnl.c:51:22: sparse: undefined identifier 'XENSND_OP_TRIGGER'
sound/xen/xen_snd_front_evtchnl.c:55:22: sparse: undefined identifier 'XENSND_OP_HW_PARAM_QUERY'
sound/xen/xen_snd_front_evtchnl.c:58:45: sparse: no member 'resp' in struct xensnd_resp
>> sound/xen/xen_snd_front_evtchnl.c:51:22: sparse: incompatible types for 'case' statement
sound/xen/xen_snd_front_evtchnl.c:55:22: sparse: incompatible types for 'case' statement
sound/xen/xen_snd_front_evtchnl.c:99:20: sparse: using member 'in_prod' in incomplete struct xensnd_event_page
sound/xen/xen_snd_front_evtchnl.c:102:25: sparse: using member 'in_cons' in incomplete struct xensnd_event_page
sound/xen/xen_snd_front_evtchnl.c:105:25: sparse: using member 'in_cons' in incomplete struct xensnd_event_page
sound/xen/xen_snd_front_evtchnl.c:108:26: sparse: undefined identifier 'XENSND_IN_RING_REF'
sound/xen/xen_snd_front_evtchnl.c:109:21: sparse: using member 'id' in incomplete struct xensnd_evt
sound/xen/xen_snd_front_evtchnl.c:112:30: sparse: using member 'type' in incomplete struct xensnd_evt
sound/xen/xen_snd_front_evtchnl.c:113:22: sparse: undefined identifier 'XENSND_EVT_CUR_POS'
sound/xen/xen_snd_front_evtchnl.c:113:22: sparse: incompatible types for 'case' statement
sound/xen/xen_snd_front_evtchnl.c:119:13: sparse: using member 'in_cons' in incomplete struct xensnd_event_page
sound/xen/xen_snd_front_evtchnl.c:213:34: sparse: undefined identifier 'XENSND_FIELD_EVT_RING_REF'
sound/xen/xen_snd_front_evtchnl.c:412:47: sparse: undefined identifier 'XENSND_FIELD_EVT_RING_REF'
sound/xen/xen_snd_front_evtchnl.c:432:47: sparse: undefined identifier 'XENSND_FIELD_EVT_RING_REF'
sound/xen/xen_snd_front_evtchnl.c:51:22: sparse: Expected constant expression in case statement
sound/xen/xen_snd_front_evtchnl.c:55:22: sparse: Expected constant expression in case statement
sound/xen/xen_snd_front_evtchnl.c:113:22: sparse: Expected constant expression in case statement
In file included from sound/xen/xen_snd_front_evtchnl.c:18:0:
sound/xen/xen_snd_front_evtchnl.h:62:34: error: field 'hw_param' has incomplete type
struct xensnd_query_hw_param hw_param;
^~~~~~~~
sound/xen/xen_snd_front_evtchnl.c: In function 'evtchnl_interrupt_req':
sound/xen/xen_snd_front_evtchnl.c:51:8: error: 'XENSND_OP_TRIGGER' undeclared (first use in this function); did you mean 'XENSND_OP_WRITE'?
case XENSND_OP_TRIGGER:
^~~~~~~~~~~~~~~~~
XENSND_OP_WRITE
sound/xen/xen_snd_front_evtchnl.c:51:8: note: each undeclared identifier is reported only once for each function it appears in
sound/xen/xen_snd_front_evtchnl.c:55:8: error: 'XENSND_OP_HW_PARAM_QUERY' undeclared (first use in this function); did you mean 'XENSND_OP_TRIGGER'?
case XENSND_OP_HW_PARAM_QUERY:
^~~~~~~~~~~~~~~~~~~~~~~~
XENSND_OP_TRIGGER
sound/xen/xen_snd_front_evtchnl.c:58:10: error: 'struct xensnd_resp' has no member named 'resp'
resp->resp.hw_param;
^~
sound/xen/xen_snd_front_evtchnl.c: In function 'evtchnl_interrupt_evt':
sound/xen/xen_snd_front_evtchnl.c:99:13: error: dereferencing pointer to incomplete type 'struct xensnd_event_page'
prod = page->in_prod;
^~
sound/xen/xen_snd_front_evtchnl.c:108:12: error: implicit declaration of function 'XENSND_IN_RING_REF'; did you mean 'XENSND_FIELD_RING_REF'? [-Werror=implicit-function-declaration]
event = &XENSND_IN_RING_REF(page, cons);
^~~~~~~~~~~~~~~~~~
XENSND_FIELD_RING_REF
sound/xen/xen_snd_front_evtchnl.c:108:11: error: lvalue required as unary '&' operand
event = &XENSND_IN_RING_REF(page, cons);
^
In file included from include/linux/kernel.h:10:0,
from include/linux/interrupt.h:6,
from include/xen/events.h:5,
from sound/xen/xen_snd_front_evtchnl.c:11:
sound/xen/xen_snd_front_evtchnl.c:109:21: error: dereferencing pointer to incomplete type 'struct xensnd_evt'
if (unlikely(event->id != channel->evt_id++))
^
include/linux/compiler.h:77:42: note: in definition of macro 'unlikely'
# define unlikely(x) __builtin_expect(!!(x), 0)
^
sound/xen/xen_snd_front_evtchnl.c:113:8: error: 'XENSND_EVT_CUR_POS' undeclared (first use in this function); did you mean 'XENSND_OP_CLOSE'?
case XENSND_EVT_CUR_POS:
^~~~~~~~~~~~~~~~~~
XENSND_OP_CLOSE
sound/xen/xen_snd_front_evtchnl.c: In function 'evtchnl_alloc':
sound/xen/xen_snd_front_evtchnl.c:213:6: error: 'XENSND_FIELD_EVT_RING_REF' undeclared (first use in this function); did you mean 'XENSND_FIELD_RING_REF'?
XENSND_FIELD_EVT_RING_REF);
^~~~~~~~~~~~~~~~~~~~~~~~~
XENSND_FIELD_RING_REF
sound/xen/xen_snd_front_evtchnl.c: In function 'xen_snd_front_evtchnl_publish_all':
sound/xen/xen_snd_front_evtchnl.c:412:12: error: 'XENSND_FIELD_EVT_RING_REF' undeclared (first use in this function); did you mean 'XENSND_FIELD_RING_REF'?
XENSND_FIELD_EVT_RING_REF,
^~~~~~~~~~~~~~~~~~~~~~~~~
XENSND_FIELD_RING_REF
sound/xen/xen_snd_front_evtchnl.c:413:12: error: 'XENSND_FIELD_EVT_EVT_CHNL' undeclared (first use in this function); did you mean 'XENSND_FIELD_EVT_CHNL'?
XENSND_FIELD_EVT_EVT_CHNL);
^~~~~~~~~~~~~~~~~~~~~~~~~
XENSND_FIELD_EVT_CHNL
cc1: some warnings being treated as errors
vim +/hw_param +62 sound/xen/xen_snd_front_evtchnl.h
39
40 struct xen_snd_front_evtchnl {
41 struct xen_snd_front_info *front_info;
42 int gref;
43 int port;
44 int irq;
45 int index;
46 /* state of the event channel */
47 enum xen_snd_front_evtchnl_state state;
48 enum xen_snd_front_evtchnl_type type;
49 /* either response id or incoming event id */
50 u16 evt_id;
51 /* next request id or next expected event id */
52 u16 evt_next_id;
53 union {
54 struct {
55 struct xen_sndif_front_ring ring;
56 struct completion completion;
57 /* latest response status */
58 int resp_status;
59 /* serializer for backend IO: request/response */
60 struct mutex req_io_lock;
61 union {
> 62 struct xensnd_query_hw_param hw_param;
63 } resp;
64 } req;
65 struct {
66 struct xensnd_event_page *page;
67 /* this is needed to handle XENSND_EVT_CUR_POS event */
68 struct snd_pcm_substream *substream;
69 } evt;
70 } u;
71 };
72
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 62903 bytes --]
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 5/5] ALSA: xen-front: Implement ALSA virtual sound driver
2018-04-16 6:24 ` [PATCH v2 5/5] ALSA: xen-front: Implement ALSA virtual sound driver Oleksandr Andrushchenko
@ 2018-04-16 14:09 ` Juergen Gross
2018-04-17 11:32 ` Oleksandr Andrushchenko
2018-04-16 14:59 ` kbuild test robot
1 sibling, 1 reply; 40+ messages in thread
From: Juergen Gross @ 2018-04-16 14:09 UTC (permalink / raw)
To: Oleksandr Andrushchenko, xen-devel, linux-kernel, alsa-devel,
boris.ostrovsky, konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>
> Implement essential initialization of the sound driver:
> - introduce required data structures
> - handle driver registration
> - handle sound card registration
> - register sound driver on backend connection
> - remove sound driver on backend disconnect
>
> Initialize virtual sound card with streams according to the
> Xen store configuration.
>
> Implement ALSA driver operations including:
> - manage frontend/backend shared buffers
> - manage Xen bus event channel states
>
> Implement requests from front to back for ALSA
> PCM operations.
> - report ALSA period elapsed event: handle XENSND_EVT_CUR_POS
> notifications from the backend when stream position advances
> during playback/capture. The event carries a value of how
> many octets were played/captured at the time of the event.
> - implement explicit stream parameter negotiation between
> backend and frontend: handle XENSND_OP_HW_PARAM_QUERY request
> to read/update configuration space for the parameter given:
> request passes desired parameter interval and the response to
> this request returns min/max interval for the parameter to be used.
>
> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> ---
> sound/xen/Makefile | 3 +-
> sound/xen/xen_snd_front.c | 193 ++++++++-
> sound/xen/xen_snd_front.h | 28 ++
> sound/xen/xen_snd_front_alsa.c | 830 ++++++++++++++++++++++++++++++++++++++
> sound/xen/xen_snd_front_alsa.h | 23 ++
> sound/xen/xen_snd_front_evtchnl.c | 6 +-
> 6 files changed, 1080 insertions(+), 3 deletions(-)
> create mode 100644 sound/xen/xen_snd_front_alsa.c
> create mode 100644 sound/xen/xen_snd_front_alsa.h
>
> diff --git a/sound/xen/Makefile b/sound/xen/Makefile
> index f028bc30af5d..1e6470ecc2f2 100644
> --- a/sound/xen/Makefile
> +++ b/sound/xen/Makefile
> @@ -3,6 +3,7 @@
> snd_xen_front-objs := xen_snd_front.o \
> xen_snd_front_cfg.o \
> xen_snd_front_evtchnl.o \
> - xen_snd_front_shbuf.o
> + xen_snd_front_shbuf.o \
> + xen_snd_front_alsa.o
>
> obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
> diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
> index 0569c6c596a3..1fef253ea21a 100644
> --- a/sound/xen/xen_snd_front.c
> +++ b/sound/xen/xen_snd_front.c
> @@ -19,10 +19,201 @@
> #include <xen/interface/io/sndif.h>
>
> #include "xen_snd_front.h"
> +#include "xen_snd_front_alsa.h"
> #include "xen_snd_front_evtchnl.h"
> +#include "xen_snd_front_shbuf.h"
> +
> +static struct xensnd_req *
> +be_stream_prepare_req(struct xen_snd_front_evtchnl *evtchnl, u8 operation)
> +{
> + struct xensnd_req *req;
> +
> + req = RING_GET_REQUEST(&evtchnl->u.req.ring,
> + evtchnl->u.req.ring.req_prod_pvt);
> + req->operation = operation;
> + req->id = evtchnl->evt_next_id++;
> + evtchnl->evt_id = req->id;
> + return req;
> +}
> +
> +static int be_stream_do_io(struct xen_snd_front_evtchnl *evtchnl)
> +{
> + if (unlikely(evtchnl->state != EVTCHNL_STATE_CONNECTED))
> + return -EIO;
> +
> + reinit_completion(&evtchnl->u.req.completion);
> + xen_snd_front_evtchnl_flush(evtchnl);
> + return 0;
> +}
> +
> +static int be_stream_wait_io(struct xen_snd_front_evtchnl *evtchnl)
> +{
> + if (wait_for_completion_timeout(&evtchnl->u.req.completion,
> + msecs_to_jiffies(VSND_WAIT_BACK_MS)) <= 0)
> + return -ETIMEDOUT;
> +
> + return evtchnl->u.req.resp_status;
> +}
> +
> +int xen_snd_front_stream_query_hw_param(struct xen_snd_front_evtchnl *evtchnl,
> + struct xensnd_query_hw_param *hw_param_req,
> + struct xensnd_query_hw_param *hw_param_resp)
> +{
> + struct xen_snd_front_info *front_info = evtchnl->front_info;
> + struct xensnd_req *req;
> + unsigned long flags;
> + int ret;
> +
> + mutex_lock(&evtchnl->u.req.req_io_lock);
> +
> + spin_lock_irqsave(&front_info->io_lock, flags);
> + req = be_stream_prepare_req(evtchnl, XENSND_OP_HW_PARAM_QUERY);
> + req->op.hw_param = *hw_param_req;
> +
> + ret = be_stream_do_io(evtchnl);
> + spin_unlock_irqrestore(&front_info->io_lock, flags);
> +
> + if (ret == 0)
> + ret = be_stream_wait_io(evtchnl);
> +
> + if (ret == 0)
> + *hw_param_resp = evtchnl->u.req.resp.hw_param;
> +
> + mutex_unlock(&evtchnl->u.req.req_io_lock);
> + return ret;
> +}
> +
> +int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl *evtchnl,
> + struct xen_snd_front_shbuf *sh_buf,
> + u8 format, unsigned int channels,
> + unsigned int rate, u32 buffer_sz,
> + u32 period_sz)
> +{
> + struct xen_snd_front_info *front_info = evtchnl->front_info;
> + struct xensnd_req *req;
> + unsigned long flags;
> + int ret;
> +
> + mutex_lock(&evtchnl->u.req.req_io_lock);
> +
> + spin_lock_irqsave(&front_info->io_lock, flags);
> + req = be_stream_prepare_req(evtchnl, XENSND_OP_OPEN);
> + req->op.open.pcm_format = format;
> + req->op.open.pcm_channels = channels;
> + req->op.open.pcm_rate = rate;
> + req->op.open.buffer_sz = buffer_sz;
> + req->op.open.period_sz = period_sz;
> + req->op.open.gref_directory = xen_snd_front_shbuf_get_dir_start(sh_buf);
> +
> + ret = be_stream_do_io(evtchnl);
> + spin_unlock_irqrestore(&front_info->io_lock, flags);
> +
> + if (ret == 0)
> + ret = be_stream_wait_io(evtchnl);
> +
> + mutex_unlock(&evtchnl->u.req.req_io_lock);
> + return ret;
> +}
> +
> +int xen_snd_front_stream_close(struct xen_snd_front_evtchnl *evtchnl)
> +{
> + struct xen_snd_front_info *front_info = evtchnl->front_info;
> + struct xensnd_req *req;
> + unsigned long flags;
> + int ret;
> +
> + mutex_lock(&evtchnl->u.req.req_io_lock);
> +
> + spin_lock_irqsave(&front_info->io_lock, flags);
> + req = be_stream_prepare_req(evtchnl, XENSND_OP_CLOSE);
> +
> + ret = be_stream_do_io(evtchnl);
> + spin_unlock_irqrestore(&front_info->io_lock, flags);
> +
> + if (ret == 0)
> + ret = be_stream_wait_io(evtchnl);
> +
> + mutex_unlock(&evtchnl->u.req.req_io_lock);
> + return ret;
> +}
> +
> +int xen_snd_front_stream_write(struct xen_snd_front_evtchnl *evtchnl,
> + unsigned long pos, unsigned long count)
> +{
> + struct xen_snd_front_info *front_info = evtchnl->front_info;
> + struct xensnd_req *req;
> + unsigned long flags;
> + int ret;
> +
> + mutex_lock(&evtchnl->u.req.req_io_lock);
> +
> + spin_lock_irqsave(&front_info->io_lock, flags);
> + req = be_stream_prepare_req(evtchnl, XENSND_OP_WRITE);
> + req->op.rw.length = count;
> + req->op.rw.offset = pos;
> +
> + ret = be_stream_do_io(evtchnl);
> + spin_unlock_irqrestore(&front_info->io_lock, flags);
> +
> + if (ret == 0)
> + ret = be_stream_wait_io(evtchnl);
> +
> + mutex_unlock(&evtchnl->u.req.req_io_lock);
> + return ret;
> +}
> +
> +int xen_snd_front_stream_read(struct xen_snd_front_evtchnl *evtchnl,
> + unsigned long pos, unsigned long count)
> +{
> + struct xen_snd_front_info *front_info = evtchnl->front_info;
> + struct xensnd_req *req;
> + unsigned long flags;
> + int ret;
> +
> + mutex_lock(&evtchnl->u.req.req_io_lock);
> +
> + spin_lock_irqsave(&front_info->io_lock, flags);
> + req = be_stream_prepare_req(evtchnl, XENSND_OP_READ);
> + req->op.rw.length = count;
> + req->op.rw.offset = pos;
> +
> + ret = be_stream_do_io(evtchnl);
> + spin_unlock_irqrestore(&front_info->io_lock, flags);
> +
> + if (ret == 0)
> + ret = be_stream_wait_io(evtchnl);
> +
> + mutex_unlock(&evtchnl->u.req.req_io_lock);
> + return ret;
> +}
> +
> +int xen_snd_front_stream_trigger(struct xen_snd_front_evtchnl *evtchnl,
> + int type)
> +{
> + struct xen_snd_front_info *front_info = evtchnl->front_info;
> + struct xensnd_req *req;
> + unsigned long flags;
> + int ret;
> +
> + mutex_lock(&evtchnl->u.req.req_io_lock);
> +
> + spin_lock_irqsave(&front_info->io_lock, flags);
> + req = be_stream_prepare_req(evtchnl, XENSND_OP_TRIGGER);
> + req->op.trigger.type = type;
> +
> + ret = be_stream_do_io(evtchnl);
> + spin_unlock_irqrestore(&front_info->io_lock, flags);
> +
> + if (ret == 0)
> + ret = be_stream_wait_io(evtchnl);
> +
> + mutex_unlock(&evtchnl->u.req.req_io_lock);
> + return ret;
> +}
>
> static void xen_snd_drv_fini(struct xen_snd_front_info *front_info)
> {
> + xen_snd_front_alsa_fini(front_info);
> xen_snd_front_evtchnl_free_all(front_info);
> }
>
> @@ -45,7 +236,7 @@ static int sndback_initwait(struct xen_snd_front_info *front_info)
>
> static int sndback_connect(struct xen_snd_front_info *front_info)
> {
> - return 0;
> + return xen_snd_front_alsa_init(front_info);
> }
>
> static void sndback_disconnect(struct xen_snd_front_info *front_info)
> diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
> index 9c2ffbb4e4b8..7adbdb4d2019 100644
> --- a/sound/xen/xen_snd_front.h
> +++ b/sound/xen/xen_snd_front.h
> @@ -13,17 +13,45 @@
>
> #include "xen_snd_front_cfg.h"
>
> +struct card_info;
> +struct xen_snd_front_evtchnl;
> struct xen_snd_front_evtchnl_pair;
> +struct xen_snd_front_shbuf;
> +struct xensnd_query_hw_param;
>
> struct xen_snd_front_info {
> struct xenbus_device *xb_dev;
>
> + struct card_info *card_info;
> +
> /* serializer for backend IO: request/response */
> spinlock_t io_lock;
> +
> int num_evt_pairs;
> struct xen_snd_front_evtchnl_pair *evt_pairs;
>
> struct xen_front_cfg_card cfg;
> };
>
> +int xen_snd_front_stream_query_hw_param(struct xen_snd_front_evtchnl *evtchnl,
> + struct xensnd_query_hw_param *hw_param_req,
> + struct xensnd_query_hw_param *hw_param_resp);
> +
> +int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl *evtchnl,
> + struct xen_snd_front_shbuf *sh_buf,
> + u8 format, unsigned int channels,
> + unsigned int rate, u32 buffer_sz,
> + u32 period_sz);
> +
> +int xen_snd_front_stream_close(struct xen_snd_front_evtchnl *evtchnl);
> +
> +int xen_snd_front_stream_write(struct xen_snd_front_evtchnl *evtchnl,
> + unsigned long pos, unsigned long count);
> +
> +int xen_snd_front_stream_read(struct xen_snd_front_evtchnl *evtchnl,
> + unsigned long pos, unsigned long count);
> +
> +int xen_snd_front_stream_trigger(struct xen_snd_front_evtchnl *evtchnl,
> + int type);
> +
> #endif /* __XEN_SND_FRONT_H */
> diff --git a/sound/xen/xen_snd_front_alsa.c b/sound/xen/xen_snd_front_alsa.c
> new file mode 100644
> index 000000000000..f524b172750e
> --- /dev/null
> +++ b/sound/xen/xen_snd_front_alsa.c
> @@ -0,0 +1,830 @@
> +// SPDX-License-Identifier: GPL-2.0 OR MIT
> +
> +/*
> + * Xen para-virtual sound device
> + *
> + * Copyright (C) 2016-2018 EPAM Systems Inc.
> + *
> + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> + */
> +
> +#include <linux/platform_device.h>
> +
> +#include <sound/core.h>
> +#include <sound/pcm.h>
> +#include <sound/pcm_params.h>
> +
> +#include <xen/xenbus.h>
> +
> +#include "xen_snd_front.h"
> +#include "xen_snd_front_alsa.h"
> +#include "xen_snd_front_cfg.h"
> +#include "xen_snd_front_evtchnl.h"
> +#include "xen_snd_front_shbuf.h"
> +
> +struct pcm_stream_info {
Not sure how this is generally handled in the sound drivers, but when
reviewing the code using those structures I repeatedly tried to find
their definitions in the sound headers instead of here. Same applies to
the alsa_* names.
I'd prefer names which don't poison the name space.
> + struct xen_snd_front_info *front_info;
> + struct xen_snd_front_evtchnl_pair *evt_pair;
> + struct xen_snd_front_shbuf sh_buf;
> + int index;
> +
> + bool is_open;
> + struct snd_pcm_hardware pcm_hw;
> +
> + /* number of processed frames as reported by the backend */
> + snd_pcm_uframes_t be_cur_frame;
> + /* current HW pointer to be reported via .period callback */
> + atomic_t hw_ptr;
> + /* modulo of the number of processed frames - for period detection */
> + u32 out_frames;
> +};
> +
> +struct pcm_instance_info {
> + struct card_info *card_info;
> + struct snd_pcm *pcm;
> + struct snd_pcm_hardware pcm_hw;
> + int num_pcm_streams_pb;
> + struct pcm_stream_info *streams_pb;
> + int num_pcm_streams_cap;
> + struct pcm_stream_info *streams_cap;
> +};
> +
> +struct card_info {
> + struct xen_snd_front_info *front_info;
> + struct snd_card *card;
> + struct snd_pcm_hardware pcm_hw;
> + int num_pcm_instances;
> + struct pcm_instance_info *pcm_instances;
> +};
> +
> +struct alsa_sndif_sample_format {
> + u8 sndif;
> + snd_pcm_format_t alsa;
> +};
> +
> +struct alsa_sndif_hw_param {
> + u8 sndif;
> + snd_pcm_hw_param_t alsa;
> +};
> +
> +static const struct alsa_sndif_sample_format ALSA_SNDIF_FORMATS[] = {
> + {
> + .sndif = XENSND_PCM_FORMAT_U8,
> + .alsa = SNDRV_PCM_FORMAT_U8
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_S8,
> + .alsa = SNDRV_PCM_FORMAT_S8
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_U16_LE,
> + .alsa = SNDRV_PCM_FORMAT_U16_LE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_U16_BE,
> + .alsa = SNDRV_PCM_FORMAT_U16_BE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_S16_LE,
> + .alsa = SNDRV_PCM_FORMAT_S16_LE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_S16_BE,
> + .alsa = SNDRV_PCM_FORMAT_S16_BE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_U24_LE,
> + .alsa = SNDRV_PCM_FORMAT_U24_LE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_U24_BE,
> + .alsa = SNDRV_PCM_FORMAT_U24_BE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_S24_LE,
> + .alsa = SNDRV_PCM_FORMAT_S24_LE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_S24_BE,
> + .alsa = SNDRV_PCM_FORMAT_S24_BE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_U32_LE,
> + .alsa = SNDRV_PCM_FORMAT_U32_LE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_U32_BE,
> + .alsa = SNDRV_PCM_FORMAT_U32_BE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_S32_LE,
> + .alsa = SNDRV_PCM_FORMAT_S32_LE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_S32_BE,
> + .alsa = SNDRV_PCM_FORMAT_S32_BE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_A_LAW,
> + .alsa = SNDRV_PCM_FORMAT_A_LAW
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_MU_LAW,
> + .alsa = SNDRV_PCM_FORMAT_MU_LAW
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_F32_LE,
> + .alsa = SNDRV_PCM_FORMAT_FLOAT_LE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_F32_BE,
> + .alsa = SNDRV_PCM_FORMAT_FLOAT_BE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_F64_LE,
> + .alsa = SNDRV_PCM_FORMAT_FLOAT64_LE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_F64_BE,
> + .alsa = SNDRV_PCM_FORMAT_FLOAT64_BE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE,
> + .alsa = SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE,
> + .alsa = SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_IMA_ADPCM,
> + .alsa = SNDRV_PCM_FORMAT_IMA_ADPCM
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_MPEG,
> + .alsa = SNDRV_PCM_FORMAT_MPEG
> + },
> + {
> + .sndif = XENSND_PCM_FORMAT_GSM,
> + .alsa = SNDRV_PCM_FORMAT_GSM
> + },
> +};
> +
> +static int to_sndif_format(snd_pcm_format_t format)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
> + if (ALSA_SNDIF_FORMATS[i].alsa == format)
> + return ALSA_SNDIF_FORMATS[i].sndif;
> +
> + return -EINVAL;
> +}
> +
> +static u64 to_sndif_formats_mask(u64 alsa_formats)
> +{
> + u64 mask;
> + int i;
> +
> + mask = 0;
> + for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
> + if (1 << ALSA_SNDIF_FORMATS[i].alsa & alsa_formats)
> + mask |= 1 << ALSA_SNDIF_FORMATS[i].sndif;
> +
> + return mask;
> +}
> +
> +static u64 to_alsa_formats_mask(u64 sndif_formats)
> +{
> + u64 mask;
> + int i;
> +
> + mask = 0;
> + for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
> + if (1 << ALSA_SNDIF_FORMATS[i].sndif & sndif_formats)
> + mask |= 1 << ALSA_SNDIF_FORMATS[i].alsa;
> +
> + return mask;
> +}
> +
> +static void stream_clear(struct pcm_stream_info *stream)
> +{
> + stream->is_open = false;
> + stream->be_cur_frame = 0;
> + stream->out_frames = 0;
> + atomic_set(&stream->hw_ptr, 0);
> + xen_snd_front_evtchnl_pair_clear(stream->evt_pair);
> + xen_snd_front_shbuf_clear(&stream->sh_buf);
> +}
> +
> +static void stream_free(struct pcm_stream_info *stream)
> +{
> + xen_snd_front_shbuf_free(&stream->sh_buf);
> + stream_clear(stream);
> +}
> +
> +static struct pcm_stream_info *stream_get(struct snd_pcm_substream *substream)
> +{
> + struct pcm_instance_info *pcm_instance =
> + snd_pcm_substream_chip(substream);
> + struct pcm_stream_info *stream;
> +
> + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
> + stream = &pcm_instance->streams_pb[substream->number];
> + else
> + stream = &pcm_instance->streams_cap[substream->number];
> +
> + return stream;
> +}
> +
> +static int alsa_hw_rule(struct snd_pcm_hw_params *params,
> + struct snd_pcm_hw_rule *rule)
> +{
> + struct pcm_stream_info *stream = rule->private;
> + struct device *dev = &stream->front_info->xb_dev->dev;
> + struct snd_mask *formats =
> + hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
> + struct snd_interval *rates =
> + hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
> + struct snd_interval *channels =
> + hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
> + struct snd_interval *period =
> + hw_param_interval(params,
> + SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
> + struct snd_interval *buffer =
> + hw_param_interval(params,
> + SNDRV_PCM_HW_PARAM_BUFFER_SIZE);
> + struct xensnd_query_hw_param req;
> + struct xensnd_query_hw_param resp;
> + struct snd_interval interval;
> + struct snd_mask mask;
> + u64 sndif_formats;
> + int changed, ret;
> +
> + /* collect all the values we need for the query */
> +
> + req.formats = to_sndif_formats_mask((u64)formats->bits[0] |
> + (u64)(formats->bits[1]) << 32);
> +
> + req.rates.min = rates->min;
> + req.rates.max = rates->max;
> +
> + req.channels.min = channels->min;
> + req.channels.max = channels->max;
> +
> + req.buffer.min = buffer->min;
> + req.buffer.max = buffer->max;
> +
> + req.period.min = period->min;
> + req.period.max = period->max;
> +
> + ret = xen_snd_front_stream_query_hw_param(&stream->evt_pair->req,
> + &req, &resp);
> + if (ret < 0) {
> + /* check if this is due to backend communication error */
> + if (ret == -EIO || ret == -ETIMEDOUT)
> + dev_err(dev, "Failed to query ALSA HW parameters\n");
> + return ret;
> + }
> +
> + /* refine HW parameters after the query */
> + changed = 0;
> +
> + sndif_formats = to_alsa_formats_mask(resp.formats);
> + snd_mask_none(&mask);
> + mask.bits[0] = (u32)sndif_formats;
> + mask.bits[1] = (u32)(sndif_formats >> 32);
> + ret = snd_mask_refine(formats, &mask);
> + if (ret < 0)
> + return ret;
> + changed |= ret;
> +
> + interval.openmin = 0;
> + interval.openmax = 0;
> + interval.integer = 1;
> +
> + interval.min = resp.rates.min;
> + interval.max = resp.rates.max;
> + ret = snd_interval_refine(rates, &interval);
> + if (ret < 0)
> + return ret;
> + changed |= ret;
> +
> + interval.min = resp.channels.min;
> + interval.max = resp.channels.max;
> + ret = snd_interval_refine(channels, &interval);
> + if (ret < 0)
> + return ret;
> + changed |= ret;
> +
> + interval.min = resp.buffer.min;
> + interval.max = resp.buffer.max;
> + ret = snd_interval_refine(buffer, &interval);
> + if (ret < 0)
> + return ret;
> + changed |= ret;
> +
> + interval.min = resp.period.min;
> + interval.max = resp.period.max;
> + ret = snd_interval_refine(period, &interval);
> + if (ret < 0)
> + return ret;
> + changed |= ret;
> +
> + return changed;
> +}
> +
> +static int alsa_open(struct snd_pcm_substream *substream)
> +{
> + struct pcm_instance_info *pcm_instance =
> + snd_pcm_substream_chip(substream);
> + struct pcm_stream_info *stream = stream_get(substream);
> + struct snd_pcm_runtime *runtime = substream->runtime;
> + struct xen_snd_front_info *front_info =
> + pcm_instance->card_info->front_info;
> + struct device *dev = &front_info->xb_dev->dev;
> + unsigned long flags;
> + int ret;
> +
> + /*
> + * return our HW properties: override defaults with those configured
> + * via XenStore
> + */
> + runtime->hw = stream->pcm_hw;
> + runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |
> + SNDRV_PCM_INFO_MMAP_VALID |
> + SNDRV_PCM_INFO_DOUBLE |
> + SNDRV_PCM_INFO_BATCH |
> + SNDRV_PCM_INFO_NONINTERLEAVED |
> + SNDRV_PCM_INFO_RESUME |
> + SNDRV_PCM_INFO_PAUSE);
> + runtime->hw.info |= SNDRV_PCM_INFO_INTERLEAVED;
> +
> + spin_lock_irqsave(&front_info->io_lock, flags);
> +
> + stream->evt_pair = &front_info->evt_pairs[stream->index];
> +
> + stream->front_info = front_info;
> +
> + xen_snd_front_evtchnl_pair_set_connected(stream->evt_pair, true);
> +
> + stream->evt_pair->evt.u.evt.substream = substream;
> +
> + stream_clear(stream);
> +
> + spin_unlock_irqrestore(&front_info->io_lock, flags);
> +
> + ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
> + alsa_hw_rule, stream,
> + SNDRV_PCM_HW_PARAM_FORMAT, -1);
> + if (ret) {
> + dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_FORMAT\n");
> + return ret;
> + }
> +
> + ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
> + alsa_hw_rule, stream,
> + SNDRV_PCM_HW_PARAM_RATE, -1);
> + if (ret) {
> + dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_RATE\n");
> + return ret;
> + }
> +
> + ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
> + alsa_hw_rule, stream,
> + SNDRV_PCM_HW_PARAM_CHANNELS, -1);
> + if (ret) {
> + dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_CHANNELS\n");
> + return ret;
> + }
> +
> + ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
> + alsa_hw_rule, stream,
> + SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
> + if (ret) {
> + dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_PERIOD_SIZE\n");
> + return ret;
> + }
> +
> + ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
> + alsa_hw_rule, stream,
> + SNDRV_PCM_HW_PARAM_BUFFER_SIZE, -1);
> + if (ret) {
> + dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_BUFFER_SIZE\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int alsa_close(struct snd_pcm_substream *substream)
> +{
> + struct pcm_stream_info *stream = stream_get(substream);
> + unsigned long flags;
> +
> + spin_lock_irqsave(&stream->front_info->io_lock, flags);
> +
> + xen_snd_front_evtchnl_pair_set_connected(stream->evt_pair, false);
> +
> + spin_unlock_irqrestore(&stream->front_info->io_lock, flags);
> + return 0;
> +}
> +
> +static int alsa_hw_params(struct snd_pcm_substream *substream,
> + struct snd_pcm_hw_params *params)
> +{
> + struct pcm_stream_info *stream = stream_get(substream);
> + int ret;
> +
> + /*
> + * this callback may be called multiple times,
> + * so free the previously allocated shared buffer if any
> + */
> + stream_free(stream);
> +
> + ret = xen_snd_front_shbuf_alloc(stream->front_info->xb_dev,
> + &stream->sh_buf,
> + params_buffer_bytes(params));
> + if (ret < 0) {
> + stream_free(stream);
> + dev_err(&stream->front_info->xb_dev->dev,
> + "Failed to allocate buffers for stream with index %d\n",
> + stream->index);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int alsa_hw_free(struct snd_pcm_substream *substream)
> +{
> + struct pcm_stream_info *stream = stream_get(substream);
> + int ret;
> +
> + ret = xen_snd_front_stream_close(&stream->evt_pair->req);
> + stream_free(stream);
> + return ret;
> +}
> +
> +static int alsa_prepare(struct snd_pcm_substream *substream)
> +{
> + struct pcm_stream_info *stream = stream_get(substream);
> +
> + if (!stream->is_open) {
> + struct snd_pcm_runtime *runtime = substream->runtime;
> + u8 sndif_format;
> + int ret;
> +
> + sndif_format = to_sndif_format(runtime->format);
> + if (sndif_format < 0) {
> + dev_err(&stream->front_info->xb_dev->dev,
> + "Unsupported sample format: %d\n",
> + runtime->format);
> + return sndif_format;
> + }
> +
> + ret = xen_snd_front_stream_prepare(&stream->evt_pair->req,
> + &stream->sh_buf,
> + sndif_format,
> + runtime->channels,
> + runtime->rate,
> + snd_pcm_lib_buffer_bytes(substream),
> + snd_pcm_lib_period_bytes(substream));
> + if (ret < 0)
> + return ret;
> +
> + stream->is_open = true;
> + }
> +
> + return 0;
> +}
> +
> +static int alsa_trigger(struct snd_pcm_substream *substream, int cmd)
> +{
> + struct pcm_stream_info *stream = stream_get(substream);
> + int type;
> +
> + switch (cmd) {
> + case SNDRV_PCM_TRIGGER_START:
> + type = XENSND_OP_TRIGGER_START;
> + break;
> +
> + case SNDRV_PCM_TRIGGER_RESUME:
> + type = XENSND_OP_TRIGGER_RESUME;
> + break;
> +
> + case SNDRV_PCM_TRIGGER_STOP:
> + type = XENSND_OP_TRIGGER_STOP;
> + break;
> +
> + case SNDRV_PCM_TRIGGER_SUSPEND:
> + type = XENSND_OP_TRIGGER_PAUSE;
> + break;
> +
> + default:
> + return -EINVAL;
> + }
> +
> + return xen_snd_front_stream_trigger(&stream->evt_pair->req, type);
> +}
> +
> +void xen_snd_front_alsa_handle_cur_pos(struct xen_snd_front_evtchnl *evtchnl,
> + u64 pos_bytes)
> +{
> + struct snd_pcm_substream *substream = evtchnl->u.evt.substream;
> + struct pcm_stream_info *stream = stream_get(substream);
> + snd_pcm_uframes_t delta, new_hw_ptr, cur_frame;
> +
> + cur_frame = bytes_to_frames(substream->runtime, pos_bytes);
> +
> + delta = cur_frame - stream->be_cur_frame;
> + stream->be_cur_frame = cur_frame;
> +
> + new_hw_ptr = (snd_pcm_uframes_t)atomic_read(&stream->hw_ptr);
> + new_hw_ptr = (new_hw_ptr + delta) % substream->runtime->buffer_size;
> + atomic_set(&stream->hw_ptr, (int)new_hw_ptr);
> +
> + stream->out_frames += delta;
> + if (stream->out_frames > substream->runtime->period_size) {
> + stream->out_frames %= substream->runtime->period_size;
> + snd_pcm_period_elapsed(substream);
> + }
> +}
> +
> +static snd_pcm_uframes_t alsa_pointer(struct snd_pcm_substream *substream)
> +{
> + struct pcm_stream_info *stream = stream_get(substream);
> +
> + return (snd_pcm_uframes_t)atomic_read(&stream->hw_ptr);
> +}
> +
> +static int alsa_pb_copy_user(struct snd_pcm_substream *substream,
> + int channel, unsigned long pos, void __user *src,
> + unsigned long count)
> +{
> + struct pcm_stream_info *stream = stream_get(substream);
> +
> + if (unlikely(pos + count > stream->sh_buf.buffer_sz))
> + return -EINVAL;
> +
> + if (copy_from_user(stream->sh_buf.buffer + pos, src, count))
> + return -EFAULT;
> +
> + return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
> +}
> +
> +static int alsa_pb_copy_kernel(struct snd_pcm_substream *substream,
> + int channel, unsigned long pos, void *src,
> + unsigned long count)
> +{
> + struct pcm_stream_info *stream = stream_get(substream);
> +
> + if (unlikely(pos + count > stream->sh_buf.buffer_sz))
> + return -EINVAL;
> +
> + memcpy(stream->sh_buf.buffer + pos, src, count);
> +
> + return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
> +}
> +
> +static int alsa_cap_copy_user(struct snd_pcm_substream *substream,
> + int channel, unsigned long pos, void __user *dst,
> + unsigned long count)
> +{
> + struct pcm_stream_info *stream = stream_get(substream);
> + int ret;
> +
> + if (unlikely(pos + count > stream->sh_buf.buffer_sz))
> + return -EINVAL;
> +
> + ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos, count);
> + if (ret < 0)
> + return ret;
> +
> + return copy_to_user(dst, stream->sh_buf.buffer + pos, count) ?
> + -EFAULT : 0;
> +}
> +
> +static int alsa_cap_copy_kernel(struct snd_pcm_substream *substream,
> + int channel, unsigned long pos, void *dst,
> + unsigned long count)
> +{
> + struct pcm_stream_info *stream = stream_get(substream);
> + int ret;
> +
> + if (unlikely(pos + count > stream->sh_buf.buffer_sz))
> + return -EINVAL;
> +
> + ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos, count);
> + if (ret < 0)
> + return ret;
> +
> + memcpy(dst, stream->sh_buf.buffer + pos, count);
> +
> + return 0;
> +}
> +
> +static int alsa_pb_fill_silence(struct snd_pcm_substream *substream,
> + int channel, unsigned long pos,
> + unsigned long count)
> +{
> + struct pcm_stream_info *stream = stream_get(substream);
> +
> + if (unlikely(pos + count > stream->sh_buf.buffer_sz))
> + return -EINVAL;
> +
> + memset(stream->sh_buf.buffer + pos, 0, count);
> +
> + return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
> +}
> +
> +/*
> + * FIXME: The mmaped data transfer is asynchronous and there is no
> + * ack signal from user-space when it is done. This is the
> + * reason it is not implemented in the PV driver as we do need
> + * to know when the buffer can be transferred to the backend.
> + */
> +
> +static struct snd_pcm_ops snd_drv_alsa_playback_ops = {
> + .open = alsa_open,
> + .close = alsa_close,
> + .ioctl = snd_pcm_lib_ioctl,
> + .hw_params = alsa_hw_params,
> + .hw_free = alsa_hw_free,
> + .prepare = alsa_prepare,
> + .trigger = alsa_trigger,
> + .pointer = alsa_pointer,
> + .copy_user = alsa_pb_copy_user,
> + .copy_kernel = alsa_pb_copy_kernel,
> + .fill_silence = alsa_pb_fill_silence,
> +};
> +
> +static struct snd_pcm_ops snd_drv_alsa_capture_ops = {
> + .open = alsa_open,
> + .close = alsa_close,
> + .ioctl = snd_pcm_lib_ioctl,
> + .hw_params = alsa_hw_params,
> + .hw_free = alsa_hw_free,
> + .prepare = alsa_prepare,
> + .trigger = alsa_trigger,
> + .pointer = alsa_pointer,
> + .copy_user = alsa_cap_copy_user,
> + .copy_kernel = alsa_cap_copy_kernel,
> +};
> +
> +static int new_pcm_instance(struct card_info *card_info,
> + struct xen_front_cfg_pcm_instance *instance_cfg,
> + struct pcm_instance_info *pcm_instance_info)
> +{
> + struct snd_pcm *pcm;
> + int ret, i;
> +
> + dev_dbg(&card_info->front_info->xb_dev->dev,
> + "New PCM device \"%s\" with id %d playback %d capture %d",
> + instance_cfg->name,
> + instance_cfg->device_id,
> + instance_cfg->num_streams_pb,
> + instance_cfg->num_streams_cap);
> +
> + pcm_instance_info->card_info = card_info;
> +
> + pcm_instance_info->pcm_hw = instance_cfg->pcm_hw;
> +
> + if (instance_cfg->num_streams_pb) {
> + pcm_instance_info->streams_pb =
> + devm_kcalloc(&card_info->card->card_dev,
> + instance_cfg->num_streams_pb,
> + sizeof(struct pcm_stream_info),
> + GFP_KERNEL);
> + if (!pcm_instance_info->streams_pb)
> + return -ENOMEM;
> + }
> +
> + if (instance_cfg->num_streams_cap) {
> + pcm_instance_info->streams_cap =
> + devm_kcalloc(&card_info->card->card_dev,
> + instance_cfg->num_streams_cap,
> + sizeof(struct pcm_stream_info),
> + GFP_KERNEL);
> + if (!pcm_instance_info->streams_cap)
> + return -ENOMEM;
> + }
> +
> + pcm_instance_info->num_pcm_streams_pb =
> + instance_cfg->num_streams_pb;
> + pcm_instance_info->num_pcm_streams_cap =
> + instance_cfg->num_streams_cap;
> +
> + for (i = 0; i < pcm_instance_info->num_pcm_streams_pb; i++) {
> + pcm_instance_info->streams_pb[i].pcm_hw =
> + instance_cfg->streams_pb[i].pcm_hw;
> + pcm_instance_info->streams_pb[i].index =
> + instance_cfg->streams_pb[i].index;
> + }
> +
> + for (i = 0; i < pcm_instance_info->num_pcm_streams_cap; i++) {
> + pcm_instance_info->streams_cap[i].pcm_hw =
> + instance_cfg->streams_cap[i].pcm_hw;
> + pcm_instance_info->streams_cap[i].index =
> + instance_cfg->streams_cap[i].index;
> + }
> +
> + ret = snd_pcm_new(card_info->card, instance_cfg->name,
> + instance_cfg->device_id,
> + instance_cfg->num_streams_pb,
> + instance_cfg->num_streams_cap,
> + &pcm);
> + if (ret < 0)
> + return ret;
> +
> + pcm->private_data = pcm_instance_info;
> + pcm->info_flags = 0;
> + /* we want to handle all PCM operations in non-atomic context */
> + pcm->nonatomic = true;
> + strncpy(pcm->name, "Virtual card PCM", sizeof(pcm->name));
> +
> + if (instance_cfg->num_streams_pb)
> + snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
> + &snd_drv_alsa_playback_ops);
> +
> + if (instance_cfg->num_streams_cap)
> + snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,
> + &snd_drv_alsa_capture_ops);
> +
> + pcm_instance_info->pcm = pcm;
> + return 0;
> +}
> +
> +int xen_snd_front_alsa_init(struct xen_snd_front_info *front_info)
> +{
> + struct device *dev = &front_info->xb_dev->dev;
> + struct xen_front_cfg_card *cfg = &front_info->cfg;
> + struct card_info *card_info;
> + struct snd_card *card;
> + int ret, i;
> +
> + dev_dbg(dev, "Creating virtual sound card\n");
> +
> + ret = snd_card_new(dev, 0, XENSND_DRIVER_NAME, THIS_MODULE,
> + sizeof(struct card_info), &card);
> + if (ret < 0)
> + return ret;
> +
> + card_info = card->private_data;
> + card_info->front_info = front_info;
> + front_info->card_info = card_info;
> + card_info->card = card;
> + card_info->pcm_instances =
> + devm_kcalloc(dev, cfg->num_pcm_instances,
> + sizeof(struct pcm_instance_info),
> + GFP_KERNEL);
> + if (!card_info->pcm_instances) {
> + ret = -ENOMEM;
> + goto fail;
> + }
> +
> + card_info->num_pcm_instances = cfg->num_pcm_instances;
> + card_info->pcm_hw = cfg->pcm_hw;
> +
> + for (i = 0; i < cfg->num_pcm_instances; i++) {
> + ret = new_pcm_instance(card_info, &cfg->pcm_instances[i],
> + &card_info->pcm_instances[i]);
> + if (ret < 0)
> + goto fail;
> + }
> +
> + strncpy(card->driver, XENSND_DRIVER_NAME, sizeof(card->driver));
> + strncpy(card->shortname, cfg->name_short, sizeof(card->shortname));
> + strncpy(card->longname, cfg->name_long, sizeof(card->longname));
> +
> + ret = snd_card_register(card);
> + if (ret < 0)
> + goto fail;
> +
> + return 0;
> +
> +fail:
> + snd_card_free(card);
> + return ret;
> +}
> +
> +void xen_snd_front_alsa_fini(struct xen_snd_front_info *front_info)
> +{
> + struct card_info *card_info;
> + struct snd_card *card;
> +
> + card_info = front_info->card_info;
> + if (!card_info)
> + return;
> +
> + card = card_info->card;
> + if (!card)
> + return;
> +
> + dev_dbg(&front_info->xb_dev->dev, "Removing virtual sound card %d\n",
> + card->number);
> + snd_card_free(card);
> +
> + /* card_info will be freed when destroying front_info->xb_dev->dev */
> + card_info->card = NULL;
> +}
> diff --git a/sound/xen/xen_snd_front_alsa.h b/sound/xen/xen_snd_front_alsa.h
> new file mode 100644
> index 000000000000..18abd9eec967
> --- /dev/null
> +++ b/sound/xen/xen_snd_front_alsa.h
> @@ -0,0 +1,23 @@
> +/* SPDX-License-Identifier: GPL-2.0 OR MIT */
> +
> +/*
> + * Xen para-virtual sound device
> + *
> + * Copyright (C) 2016-2018 EPAM Systems Inc.
> + *
> + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> + */
> +
> +#ifndef __XEN_SND_FRONT_ALSA_H
> +#define __XEN_SND_FRONT_ALSA_H
> +
> +struct xen_snd_front_info;
> +
> +int xen_snd_front_alsa_init(struct xen_snd_front_info *front_info);
> +
> +void xen_snd_front_alsa_fini(struct xen_snd_front_info *front_info);
> +
> +void xen_snd_front_alsa_handle_cur_pos(struct xen_snd_front_evtchnl *evtchnl,
> + u64 pos_bytes);
> +
> +#endif /* __XEN_SND_FRONT_ALSA_H */
> diff --git a/sound/xen/xen_snd_front_evtchnl.c b/sound/xen/xen_snd_front_evtchnl.c
> index 9ece39f938f8..470196518716 100644
> --- a/sound/xen/xen_snd_front_evtchnl.c
> +++ b/sound/xen/xen_snd_front_evtchnl.c
> @@ -14,6 +14,7 @@
> #include <xen/xenbus.h>
>
> #include "xen_snd_front.h"
> +#include "xen_snd_front_alsa.h"
> #include "xen_snd_front_cfg.h"
> #include "xen_snd_front_evtchnl.h"
>
> @@ -111,7 +112,10 @@ static irqreturn_t evtchnl_interrupt_evt(int irq, void *dev_id)
>
> switch (event->type) {
> case XENSND_EVT_CUR_POS:
> - /* do nothing at the moment */
> + spin_unlock_irqrestore(&front_info->io_lock, flags);
> + xen_snd_front_alsa_handle_cur_pos(channel,
> + event->op.cur_pos.position);
> + spin_lock_irqsave(&front_info->io_lock, flags);
Is this correct? Why can you free the lock here without doing any
harm? What is the lock protecting? I'd like to see at least some
comments explaining why the lock is needed and why it can be dropped
here.
Juergen
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 5/5] ALSA: xen-front: Implement ALSA virtual sound driver
2018-04-16 6:24 ` [PATCH v2 5/5] ALSA: xen-front: Implement ALSA virtual sound driver Oleksandr Andrushchenko
2018-04-16 14:09 ` Juergen Gross
@ 2018-04-16 14:59 ` kbuild test robot
1 sibling, 0 replies; 40+ messages in thread
From: kbuild test robot @ 2018-04-16 14:59 UTC (permalink / raw)
To: Oleksandr Andrushchenko
Cc: kbuild-all, xen-devel, linux-kernel, alsa-devel, jgross,
boris.ostrovsky, konrad.wilk, perex, tiwai, andr2000,
Oleksandr Andrushchenko
[-- Attachment #1: Type: text/plain, Size: 23912 bytes --]
Hi Oleksandr,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on sound/for-next]
[also build test ERROR on v4.17-rc1 next-20180416]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Oleksandr-Andrushchenko/ALSA-xen-front-Add-Xen-para-virtualized-frontend-driver/20180416-143123
base: https://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound.git for-next
config: x86_64-allmodconfig (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
All errors (new ones prefixed by >>):
sound/xen/xen_snd_front.c:70:46: sparse: undefined identifier 'XENSND_OP_HW_PARAM_QUERY'
sound/xen/xen_snd_front.c:71:16: sparse: no member 'hw_param' in union <unnamed>
sound/xen/xen_snd_front.c:105:21: sparse: no member 'period_sz' in struct xensnd_open_req
sound/xen/xen_snd_front.c:201:46: sparse: undefined identifier 'XENSND_OP_TRIGGER'
sound/xen/xen_snd_front.c:202:16: sparse: no member 'trigger' in union <unnamed>
sound/xen/xen_snd_front.c:70:36: sparse: call with no type!
sound/xen/xen_snd_front.c:71:16: sparse: generating address of non-lvalue (8)
sound/xen/xen_snd_front.c:105:21: sparse: generating address of non-lvalue (8)
sound/xen/xen_snd_front.c:201:36: sparse: call with no type!
In file included from sound/xen/xen_snd_front.c:23:0:
sound/xen/xen_snd_front_evtchnl.h:62:34: error: field 'hw_param' has incomplete type
struct xensnd_query_hw_param hw_param;
^~~~~~~~
sound/xen/xen_snd_front.c: In function 'xen_snd_front_stream_query_hw_param':
>> sound/xen/xen_snd_front.c:70:39: error: 'XENSND_OP_HW_PARAM_QUERY' undeclared (first use in this function); did you mean 'XENSND_OP_WRITE'?
req = be_stream_prepare_req(evtchnl, XENSND_OP_HW_PARAM_QUERY);
^~~~~~~~~~~~~~~~~~~~~~~~
XENSND_OP_WRITE
sound/xen/xen_snd_front.c:70:39: note: each undeclared identifier is reported only once for each function it appears in
>> sound/xen/xen_snd_front.c:71:9: error: 'union <anonymous>' has no member named 'hw_param'
req->op.hw_param = *hw_param_req;
^
>> sound/xen/xen_snd_front.c:71:21: error: dereferencing pointer to incomplete type 'struct xensnd_query_hw_param'
req->op.hw_param = *hw_param_req;
^~~~~~~~~~~~~
sound/xen/xen_snd_front.c: In function 'xen_snd_front_stream_prepare':
>> sound/xen/xen_snd_front.c:105:14: error: 'struct xensnd_open_req' has no member named 'period_sz'
req->op.open.period_sz = period_sz;
^
sound/xen/xen_snd_front.c: In function 'xen_snd_front_stream_trigger':
>> sound/xen/xen_snd_front.c:201:39: error: 'XENSND_OP_TRIGGER' undeclared (first use in this function); did you mean 'XENSND_OP_WRITE'?
req = be_stream_prepare_req(evtchnl, XENSND_OP_TRIGGER);
^~~~~~~~~~~~~~~~~
XENSND_OP_WRITE
>> sound/xen/xen_snd_front.c:202:9: error: 'union <anonymous>' has no member named 'trigger'
req->op.trigger.type = type;
^
--
sound/xen/xen_snd_front_alsa.c:191:47: sparse: restricted snd_pcm_format_t degrades to integer
sound/xen/xen_snd_front_alsa.c:205:59: sparse: restricted snd_pcm_format_t degrades to integer
sound/xen/xen_snd_front_alsa.c:266:12: sparse: using member 'formats' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:269:12: sparse: using member 'rates' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:270:12: sparse: using member 'rates' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:272:12: sparse: using member 'channels' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:273:12: sparse: using member 'channels' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:275:12: sparse: using member 'buffer' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:276:12: sparse: using member 'buffer' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:278:12: sparse: using member 'period' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:279:12: sparse: using member 'period' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:293:50: sparse: using member 'formats' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:306:28: sparse: using member 'rates' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:307:28: sparse: using member 'rates' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:313:28: sparse: using member 'channels' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:314:28: sparse: using member 'channels' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:320:28: sparse: using member 'buffer' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:321:28: sparse: using member 'buffer' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:327:28: sparse: using member 'period' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:328:28: sparse: using member 'period' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:509:24: sparse: undefined identifier 'XENSND_OP_TRIGGER_START'
sound/xen/xen_snd_front_alsa.c:513:24: sparse: undefined identifier 'XENSND_OP_TRIGGER_RESUME'
sound/xen/xen_snd_front_alsa.c:517:24: sparse: undefined identifier 'XENSND_OP_TRIGGER_STOP'
sound/xen/xen_snd_front_alsa.c:521:24: sparse: undefined identifier 'XENSND_OP_TRIGGER_PAUSE'
sound/xen/xen_snd_front_alsa.c:266:44: sparse: call with no type!
sound/xen/xen_snd_front_alsa.c:266:12: sparse: generating address of non-lvalue (8)
sound/xen/xen_snd_front_alsa.c:269:30: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:270:30: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:272:36: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:273:36: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:275:32: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:276:32: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:278:32: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:279:32: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:293:45: sparse: call with no type!
sound/xen/xen_snd_front_alsa.c:306:34: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:307:34: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:313:37: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:314:37: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:320:35: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:321:35: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:327:35: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:328:35: sparse: unknown expression (8 46)
In file included from sound/xen/xen_snd_front_alsa.c:22:0:
sound/xen/xen_snd_front_evtchnl.h:62:34: error: field 'hw_param' has incomplete type
struct xensnd_query_hw_param hw_param;
^~~~~~~~
sound/xen/xen_snd_front_alsa.c: In function 'alsa_hw_rule':
>> sound/xen/xen_snd_front_alsa.c:257:31: error: storage size of 'req' isn't known
struct xensnd_query_hw_param req;
^~~
>> sound/xen/xen_snd_front_alsa.c:258:31: error: storage size of 'resp' isn't known
struct xensnd_query_hw_param resp;
^~~~
sound/xen/xen_snd_front_alsa.c:258:31: warning: unused variable 'resp' [-Wunused-variable]
sound/xen/xen_snd_front_alsa.c:257:31: warning: unused variable 'req' [-Wunused-variable]
struct xensnd_query_hw_param req;
^~~
sound/xen/xen_snd_front_alsa.c: In function 'alsa_trigger':
>> sound/xen/xen_snd_front_alsa.c:509:10: error: 'XENSND_OP_TRIGGER_START' undeclared (first use in this function); did you mean 'SNDRV_PCM_TRIGGER_START'?
type = XENSND_OP_TRIGGER_START;
^~~~~~~~~~~~~~~~~~~~~~~
SNDRV_PCM_TRIGGER_START
sound/xen/xen_snd_front_alsa.c:509:10: note: each undeclared identifier is reported only once for each function it appears in
>> sound/xen/xen_snd_front_alsa.c:513:10: error: 'XENSND_OP_TRIGGER_RESUME' undeclared (first use in this function); did you mean 'XENSND_OP_TRIGGER_START'?
type = XENSND_OP_TRIGGER_RESUME;
^~~~~~~~~~~~~~~~~~~~~~~~
XENSND_OP_TRIGGER_START
>> sound/xen/xen_snd_front_alsa.c:517:10: error: 'XENSND_OP_TRIGGER_STOP' undeclared (first use in this function); did you mean 'XENSND_OP_TRIGGER_START'?
type = XENSND_OP_TRIGGER_STOP;
^~~~~~~~~~~~~~~~~~~~~~
XENSND_OP_TRIGGER_START
>> sound/xen/xen_snd_front_alsa.c:521:10: error: 'XENSND_OP_TRIGGER_PAUSE' undeclared (first use in this function); did you mean 'XENSND_OP_TRIGGER_RESUME'?
type = XENSND_OP_TRIGGER_PAUSE;
^~~~~~~~~~~~~~~~~~~~~~~
XENSND_OP_TRIGGER_RESUME
sparse warnings: (new ones prefixed by >>)
sound/xen/xen_snd_front.c:70:46: sparse: undefined identifier 'XENSND_OP_HW_PARAM_QUERY'
sound/xen/xen_snd_front.c:71:16: sparse: no member 'hw_param' in union <unnamed>
sound/xen/xen_snd_front.c:105:21: sparse: no member 'period_sz' in struct xensnd_open_req
sound/xen/xen_snd_front.c:201:46: sparse: undefined identifier 'XENSND_OP_TRIGGER'
sound/xen/xen_snd_front.c:202:16: sparse: no member 'trigger' in union <unnamed>
>> sound/xen/xen_snd_front.c:70:36: sparse: call with no type!
>> sound/xen/xen_snd_front.c:71:16: sparse: generating address of non-lvalue (8)
sound/xen/xen_snd_front.c:105:21: sparse: generating address of non-lvalue (8)
sound/xen/xen_snd_front.c:201:36: sparse: call with no type!
In file included from sound/xen/xen_snd_front.c:23:0:
sound/xen/xen_snd_front_evtchnl.h:62:34: error: field 'hw_param' has incomplete type
struct xensnd_query_hw_param hw_param;
^~~~~~~~
sound/xen/xen_snd_front.c: In function 'xen_snd_front_stream_query_hw_param':
sound/xen/xen_snd_front.c:70:39: error: 'XENSND_OP_HW_PARAM_QUERY' undeclared (first use in this function); did you mean 'XENSND_OP_WRITE'?
req = be_stream_prepare_req(evtchnl, XENSND_OP_HW_PARAM_QUERY);
^~~~~~~~~~~~~~~~~~~~~~~~
XENSND_OP_WRITE
sound/xen/xen_snd_front.c:70:39: note: each undeclared identifier is reported only once for each function it appears in
sound/xen/xen_snd_front.c:71:9: error: 'union <anonymous>' has no member named 'hw_param'
req->op.hw_param = *hw_param_req;
^
sound/xen/xen_snd_front.c:71:21: error: dereferencing pointer to incomplete type 'struct xensnd_query_hw_param'
req->op.hw_param = *hw_param_req;
^~~~~~~~~~~~~
sound/xen/xen_snd_front.c: In function 'xen_snd_front_stream_prepare':
sound/xen/xen_snd_front.c:105:14: error: 'struct xensnd_open_req' has no member named 'period_sz'
req->op.open.period_sz = period_sz;
^
sound/xen/xen_snd_front.c: In function 'xen_snd_front_stream_trigger':
sound/xen/xen_snd_front.c:201:39: error: 'XENSND_OP_TRIGGER' undeclared (first use in this function); did you mean 'XENSND_OP_WRITE'?
req = be_stream_prepare_req(evtchnl, XENSND_OP_TRIGGER);
^~~~~~~~~~~~~~~~~
XENSND_OP_WRITE
sound/xen/xen_snd_front.c:202:9: error: 'union <anonymous>' has no member named 'trigger'
req->op.trigger.type = type;
^
--
>> sound/xen/xen_snd_front_alsa.c:191:47: sparse: restricted snd_pcm_format_t degrades to integer
sound/xen/xen_snd_front_alsa.c:205:59: sparse: restricted snd_pcm_format_t degrades to integer
sound/xen/xen_snd_front_alsa.c:266:12: sparse: using member 'formats' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:269:12: sparse: using member 'rates' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:270:12: sparse: using member 'rates' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:272:12: sparse: using member 'channels' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:273:12: sparse: using member 'channels' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:275:12: sparse: using member 'buffer' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:276:12: sparse: using member 'buffer' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:278:12: sparse: using member 'period' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:279:12: sparse: using member 'period' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:293:50: sparse: using member 'formats' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:306:28: sparse: using member 'rates' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:307:28: sparse: using member 'rates' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:313:28: sparse: using member 'channels' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:314:28: sparse: using member 'channels' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:320:28: sparse: using member 'buffer' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:321:28: sparse: using member 'buffer' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:327:28: sparse: using member 'period' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:328:28: sparse: using member 'period' in incomplete struct xensnd_query_hw_param
sound/xen/xen_snd_front_alsa.c:509:24: sparse: undefined identifier 'XENSND_OP_TRIGGER_START'
sound/xen/xen_snd_front_alsa.c:513:24: sparse: undefined identifier 'XENSND_OP_TRIGGER_RESUME'
sound/xen/xen_snd_front_alsa.c:517:24: sparse: undefined identifier 'XENSND_OP_TRIGGER_STOP'
sound/xen/xen_snd_front_alsa.c:521:24: sparse: undefined identifier 'XENSND_OP_TRIGGER_PAUSE'
>> sound/xen/xen_snd_front_alsa.c:266:44: sparse: call with no type!
>> sound/xen/xen_snd_front_alsa.c:266:12: sparse: generating address of non-lvalue (8)
>> sound/xen/xen_snd_front_alsa.c:269:30: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:270:30: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:272:36: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:273:36: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:275:32: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:276:32: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:278:32: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:279:32: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:293:45: sparse: call with no type!
sound/xen/xen_snd_front_alsa.c:306:34: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:307:34: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:313:37: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:314:37: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:320:35: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:321:35: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:327:35: sparse: unknown expression (8 46)
sound/xen/xen_snd_front_alsa.c:328:35: sparse: unknown expression (8 46)
In file included from sound/xen/xen_snd_front_alsa.c:22:0:
sound/xen/xen_snd_front_evtchnl.h:62:34: error: field 'hw_param' has incomplete type
struct xensnd_query_hw_param hw_param;
^~~~~~~~
sound/xen/xen_snd_front_alsa.c: In function 'alsa_hw_rule':
sound/xen/xen_snd_front_alsa.c:257:31: error: storage size of 'req' isn't known
struct xensnd_query_hw_param req;
^~~
sound/xen/xen_snd_front_alsa.c:258:31: error: storage size of 'resp' isn't known
struct xensnd_query_hw_param resp;
^~~~
sound/xen/xen_snd_front_alsa.c:258:31: warning: unused variable 'resp' [-Wunused-variable]
sound/xen/xen_snd_front_alsa.c:257:31: warning: unused variable 'req' [-Wunused-variable]
struct xensnd_query_hw_param req;
^~~
sound/xen/xen_snd_front_alsa.c: In function 'alsa_trigger':
sound/xen/xen_snd_front_alsa.c:509:10: error: 'XENSND_OP_TRIGGER_START' undeclared (first use in this function); did you mean 'SNDRV_PCM_TRIGGER_START'?
type = XENSND_OP_TRIGGER_START;
^~~~~~~~~~~~~~~~~~~~~~~
SNDRV_PCM_TRIGGER_START
sound/xen/xen_snd_front_alsa.c:509:10: note: each undeclared identifier is reported only once for each function it appears in
sound/xen/xen_snd_front_alsa.c:513:10: error: 'XENSND_OP_TRIGGER_RESUME' undeclared (first use in this function); did you mean 'XENSND_OP_TRIGGER_START'?
type = XENSND_OP_TRIGGER_RESUME;
^~~~~~~~~~~~~~~~~~~~~~~~
XENSND_OP_TRIGGER_START
sound/xen/xen_snd_front_alsa.c:517:10: error: 'XENSND_OP_TRIGGER_STOP' undeclared (first use in this function); did you mean 'XENSND_OP_TRIGGER_START'?
type = XENSND_OP_TRIGGER_STOP;
^~~~~~~~~~~~~~~~~~~~~~
XENSND_OP_TRIGGER_START
sound/xen/xen_snd_front_alsa.c:521:10: error: 'XENSND_OP_TRIGGER_PAUSE' undeclared (first use in this function); did you mean 'XENSND_OP_TRIGGER_RESUME'?
type = XENSND_OP_TRIGGER_PAUSE;
^~~~~~~~~~~~~~~~~~~~~~~
XENSND_OP_TRIGGER_RESUME
vim +70 sound/xen/xen_snd_front.c
57
58 int xen_snd_front_stream_query_hw_param(struct xen_snd_front_evtchnl *evtchnl,
59 struct xensnd_query_hw_param *hw_param_req,
60 struct xensnd_query_hw_param *hw_param_resp)
61 {
62 struct xen_snd_front_info *front_info = evtchnl->front_info;
63 struct xensnd_req *req;
64 unsigned long flags;
65 int ret;
66
67 mutex_lock(&evtchnl->u.req.req_io_lock);
68
69 spin_lock_irqsave(&front_info->io_lock, flags);
> 70 req = be_stream_prepare_req(evtchnl, XENSND_OP_HW_PARAM_QUERY);
> 71 req->op.hw_param = *hw_param_req;
72
73 ret = be_stream_do_io(evtchnl);
74 spin_unlock_irqrestore(&front_info->io_lock, flags);
75
76 if (ret == 0)
77 ret = be_stream_wait_io(evtchnl);
78
79 if (ret == 0)
80 *hw_param_resp = evtchnl->u.req.resp.hw_param;
81
82 mutex_unlock(&evtchnl->u.req.req_io_lock);
83 return ret;
84 }
85
86 int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl *evtchnl,
87 struct xen_snd_front_shbuf *sh_buf,
88 u8 format, unsigned int channels,
89 unsigned int rate, u32 buffer_sz,
90 u32 period_sz)
91 {
92 struct xen_snd_front_info *front_info = evtchnl->front_info;
93 struct xensnd_req *req;
94 unsigned long flags;
95 int ret;
96
97 mutex_lock(&evtchnl->u.req.req_io_lock);
98
99 spin_lock_irqsave(&front_info->io_lock, flags);
100 req = be_stream_prepare_req(evtchnl, XENSND_OP_OPEN);
101 req->op.open.pcm_format = format;
102 req->op.open.pcm_channels = channels;
103 req->op.open.pcm_rate = rate;
104 req->op.open.buffer_sz = buffer_sz;
> 105 req->op.open.period_sz = period_sz;
106 req->op.open.gref_directory = xen_snd_front_shbuf_get_dir_start(sh_buf);
107
108 ret = be_stream_do_io(evtchnl);
109 spin_unlock_irqrestore(&front_info->io_lock, flags);
110
111 if (ret == 0)
112 ret = be_stream_wait_io(evtchnl);
113
114 mutex_unlock(&evtchnl->u.req.req_io_lock);
115 return ret;
116 }
117
118 int xen_snd_front_stream_close(struct xen_snd_front_evtchnl *evtchnl)
119 {
120 struct xen_snd_front_info *front_info = evtchnl->front_info;
121 struct xensnd_req *req;
122 unsigned long flags;
123 int ret;
124
125 mutex_lock(&evtchnl->u.req.req_io_lock);
126
127 spin_lock_irqsave(&front_info->io_lock, flags);
128 req = be_stream_prepare_req(evtchnl, XENSND_OP_CLOSE);
129
130 ret = be_stream_do_io(evtchnl);
131 spin_unlock_irqrestore(&front_info->io_lock, flags);
132
133 if (ret == 0)
134 ret = be_stream_wait_io(evtchnl);
135
136 mutex_unlock(&evtchnl->u.req.req_io_lock);
137 return ret;
138 }
139
140 int xen_snd_front_stream_write(struct xen_snd_front_evtchnl *evtchnl,
141 unsigned long pos, unsigned long count)
142 {
143 struct xen_snd_front_info *front_info = evtchnl->front_info;
144 struct xensnd_req *req;
145 unsigned long flags;
146 int ret;
147
148 mutex_lock(&evtchnl->u.req.req_io_lock);
149
150 spin_lock_irqsave(&front_info->io_lock, flags);
151 req = be_stream_prepare_req(evtchnl, XENSND_OP_WRITE);
152 req->op.rw.length = count;
153 req->op.rw.offset = pos;
154
155 ret = be_stream_do_io(evtchnl);
156 spin_unlock_irqrestore(&front_info->io_lock, flags);
157
158 if (ret == 0)
159 ret = be_stream_wait_io(evtchnl);
160
161 mutex_unlock(&evtchnl->u.req.req_io_lock);
162 return ret;
163 }
164
165 int xen_snd_front_stream_read(struct xen_snd_front_evtchnl *evtchnl,
166 unsigned long pos, unsigned long count)
167 {
168 struct xen_snd_front_info *front_info = evtchnl->front_info;
169 struct xensnd_req *req;
170 unsigned long flags;
171 int ret;
172
173 mutex_lock(&evtchnl->u.req.req_io_lock);
174
175 spin_lock_irqsave(&front_info->io_lock, flags);
176 req = be_stream_prepare_req(evtchnl, XENSND_OP_READ);
177 req->op.rw.length = count;
178 req->op.rw.offset = pos;
179
180 ret = be_stream_do_io(evtchnl);
181 spin_unlock_irqrestore(&front_info->io_lock, flags);
182
183 if (ret == 0)
184 ret = be_stream_wait_io(evtchnl);
185
186 mutex_unlock(&evtchnl->u.req.req_io_lock);
187 return ret;
188 }
189
190 int xen_snd_front_stream_trigger(struct xen_snd_front_evtchnl *evtchnl,
191 int type)
192 {
193 struct xen_snd_front_info *front_info = evtchnl->front_info;
194 struct xensnd_req *req;
195 unsigned long flags;
196 int ret;
197
198 mutex_lock(&evtchnl->u.req.req_io_lock);
199
200 spin_lock_irqsave(&front_info->io_lock, flags);
> 201 req = be_stream_prepare_req(evtchnl, XENSND_OP_TRIGGER);
> 202 req->op.trigger.type = type;
203
204 ret = be_stream_do_io(evtchnl);
205 spin_unlock_irqrestore(&front_info->io_lock, flags);
206
207 if (ret == 0)
208 ret = be_stream_wait_io(evtchnl);
209
210 mutex_unlock(&evtchnl->u.req.req_io_lock);
211 return ret;
212 }
213
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 62903 bytes --]
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 1/5] ALSA: xen-front: Introduce Xen para-virtualized sound frontend driver
2018-04-16 12:25 ` Juergen Gross
@ 2018-04-17 8:24 ` Oleksandr Andrushchenko
0 siblings, 0 replies; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-17 8:24 UTC (permalink / raw)
To: Juergen Gross, xen-devel, linux-kernel, alsa-devel,
boris.ostrovsky, konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 04/16/2018 03:25 PM, Juergen Gross wrote:
> On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>
>> Introduce skeleton of the para-virtualized Xen sound
>> frontend driver.
>>
>> Initial handling for Xen bus states: implement
>> Xen bus state machine for the frontend driver according to
>> the state diagram and recovery flow from sound para-virtualized
>> protocol: xen/interface/io/sndif.h.
>>
>> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> Only one minor nit (see below). With that addressed (or fixed when
> committing):
will fix
> Reviewed-by: Juergen Gross <jgross@suse.com>
Thank you
>
> Juergen
>
>> ---
>> sound/Kconfig | 2 +
>> sound/Makefile | 2 +-
>> sound/xen/Kconfig | 10 +++
>> sound/xen/Makefile | 5 ++
>> sound/xen/xen_snd_front.c | 196 ++++++++++++++++++++++++++++++++++++++++++++++
>> sound/xen/xen_snd_front.h | 18 +++++
>> 6 files changed, 232 insertions(+), 1 deletion(-)
>> create mode 100644 sound/xen/Kconfig
>> create mode 100644 sound/xen/Makefile
>> create mode 100644 sound/xen/xen_snd_front.c
>> create mode 100644 sound/xen/xen_snd_front.h
>>
>> diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
>> new file mode 100644
>> index 000000000000..f406a8f52c51
>> --- /dev/null
>> +++ b/sound/xen/xen_snd_front.c
>> @@ -0,0 +1,196 @@
>> +static void sndback_changed(struct xenbus_device *xb_dev,
>> + enum xenbus_state backend_state)
>> +{
>> + struct xen_snd_front_info *front_info = dev_get_drvdata(&xb_dev->dev);
>> + int ret;
>> +
>> + dev_dbg(&xb_dev->dev, "Backend state is %s, front is %s\n",
>> + xenbus_strstate(backend_state),
>> + xenbus_strstate(xb_dev->state));
>> +
>> + switch (backend_state) {
>> + case XenbusStateReconfiguring:
>> + /* fall through */
>> + case XenbusStateReconfigured:
>> + /* fall through */
>> + case XenbusStateInitialised:
>> + /* fall through */
>> + break;
>> +
>> + case XenbusStateInitialising:
>> + /* recovering after backend unexpected closure */
>> + sndback_disconnect(front_info);
>> + break;
>> +
>> + case XenbusStateInitWait:
>> + /* recovering after backend unexpected closure */
>> + sndback_disconnect(front_info);
>> +
>> + ret = sndback_initwait(front_info);
>> + if (ret < 0)
>> + xenbus_dev_fatal(xb_dev, ret, "initializing frontend");
>> + else
>> + xenbus_switch_state(xb_dev, XenbusStateInitialised);
>> + break;
>> +
>> + case XenbusStateConnected:
>> + if (xb_dev->state != XenbusStateInitialised)
>> + break;
>> +
>> + ret = sndback_connect(front_info);
>> + if (ret < 0)
>> + xenbus_dev_fatal(xb_dev, ret, "initializing frontend");
>> + else
>> + xenbus_switch_state(xb_dev, XenbusStateConnected);
>> + break;
>> +
>> + case XenbusStateClosing:
>> + /*
>> + * in this state backend starts freeing resources,
>> + * so let it go into closed state first, so we can also
>> + * remove ours
>> + */
> Please start the sentence with a capital letter and end it with a
> full stop.
>
>
> Juergen
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 2/5] ALSA: xen-front: Read sound driver configuration from Xen store
2018-04-16 12:55 ` Juergen Gross
@ 2018-04-17 8:42 ` Oleksandr Andrushchenko
2018-04-17 11:08 ` Juergen Gross
0 siblings, 1 reply; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-17 8:42 UTC (permalink / raw)
To: Juergen Gross, xen-devel, linux-kernel, alsa-devel,
boris.ostrovsky, konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 04/16/2018 03:55 PM, Juergen Gross wrote:
> On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>
>> Read configuration values from Xen store according
>> to xen/interface/io/sndif.h protocol:
>> - introduce configuration structures for different
>> components, e.g. sound card, device, stream
>> - read PCM HW parameters, e.g rate, format etc.
>> - detect stream type (capture/playback)
>> - read device and card parameters
>>
>> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>> ---
>> sound/xen/Makefile | 3 +-
>> sound/xen/xen_snd_front.c | 7 +
>> sound/xen/xen_snd_front.h | 4 +
>> sound/xen/xen_snd_front_cfg.c | 517 ++++++++++++++++++++++++++++++++++++++++++
>> sound/xen/xen_snd_front_cfg.h | 46 ++++
>> 5 files changed, 576 insertions(+), 1 deletion(-)
>> create mode 100644 sound/xen/xen_snd_front_cfg.c
>> create mode 100644 sound/xen/xen_snd_front_cfg.h
>>
>> diff --git a/sound/xen/Makefile b/sound/xen/Makefile
>> index 4507ef3c27fd..06705bef61fa 100644
>> --- a/sound/xen/Makefile
>> +++ b/sound/xen/Makefile
>> @@ -1,5 +1,6 @@
>> # SPDX-License-Identifier: GPL-2.0 OR MIT
>>
>> -snd_xen_front-objs := xen_snd_front.o
>> +snd_xen_front-objs := xen_snd_front.o \
>> + xen_snd_front_cfg.o
>>
>> obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
>> diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
>> index f406a8f52c51..65d2494a9d14 100644
>> --- a/sound/xen/xen_snd_front.c
>> +++ b/sound/xen/xen_snd_front.c
>> @@ -25,6 +25,13 @@ static void xen_snd_drv_fini(struct xen_snd_front_info *front_info)
>>
>> static int sndback_initwait(struct xen_snd_front_info *front_info)
>> {
>> + int num_streams;
>> + int ret;
>> +
>> + ret = xen_snd_front_cfg_card(front_info, &num_streams);
>> + if (ret < 0)
>> + return ret;
>> +
>> return 0;
>> }
>>
>> diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
>> index 4ae204b23d32..b52226cb30bc 100644
>> --- a/sound/xen/xen_snd_front.h
>> +++ b/sound/xen/xen_snd_front.h
>> @@ -11,8 +11,12 @@
>> #ifndef __XEN_SND_FRONT_H
>> #define __XEN_SND_FRONT_H
>>
>> +#include "xen_snd_front_cfg.h"
>> +
>> struct xen_snd_front_info {
>> struct xenbus_device *xb_dev;
>> +
>> + struct xen_front_cfg_card cfg;
>> };
>>
>> #endif /* __XEN_SND_FRONT_H */
>> diff --git a/sound/xen/xen_snd_front_cfg.c b/sound/xen/xen_snd_front_cfg.c
>> new file mode 100644
>> index 000000000000..d461985afffa
>> --- /dev/null
>> +++ b/sound/xen/xen_snd_front_cfg.c
>> @@ -0,0 +1,517 @@
>> +// SPDX-License-Identifier: GPL-2.0 OR MIT
>> +
>> +/*
>> + * Xen para-virtual sound device
>> + *
>> + * Copyright (C) 2016-2018 EPAM Systems Inc.
>> + *
>> + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>> + */
>> +
>> +#include <xen/xenbus.h>
>> +
>> +#include <xen/interface/io/sndif.h>
>> +
>> +#include "xen_snd_front.h"
>> +#include "xen_snd_front_cfg.h"
>> +
>> +/* maximum number of supported streams */
> Comment style (multiple times below, too):
> Start with a capital letter and end sentences with a full stop.
will fix
>> +#define VSND_MAX_STREAM 8
>> +
>> +struct cfg_hw_sample_rate {
>> + const char *name;
>> + unsigned int mask;
>> + unsigned int value;
>> +};
>> +
>> +static const struct cfg_hw_sample_rate CFG_HW_SUPPORTED_RATES[] = {
>> + { .name = "5512", .mask = SNDRV_PCM_RATE_5512, .value = 5512 },
>> + { .name = "8000", .mask = SNDRV_PCM_RATE_8000, .value = 8000 },
>> + { .name = "11025", .mask = SNDRV_PCM_RATE_11025, .value = 11025 },
>> + { .name = "16000", .mask = SNDRV_PCM_RATE_16000, .value = 16000 },
>> + { .name = "22050", .mask = SNDRV_PCM_RATE_22050, .value = 22050 },
>> + { .name = "32000", .mask = SNDRV_PCM_RATE_32000, .value = 32000 },
>> + { .name = "44100", .mask = SNDRV_PCM_RATE_44100, .value = 44100 },
>> + { .name = "48000", .mask = SNDRV_PCM_RATE_48000, .value = 48000 },
>> + { .name = "64000", .mask = SNDRV_PCM_RATE_64000, .value = 64000 },
>> + { .name = "96000", .mask = SNDRV_PCM_RATE_96000, .value = 96000 },
>> + { .name = "176400", .mask = SNDRV_PCM_RATE_176400, .value = 176400 },
>> + { .name = "192000", .mask = SNDRV_PCM_RATE_192000, .value = 192000 },
>> +};
>> +
>> +struct cfg_hw_sample_format {
>> + const char *name;
>> + u64 mask;
>> +};
>> +
>> +static const struct cfg_hw_sample_format CFG_HW_SUPPORTED_FORMATS[] = {
>> + {
>> + .name = XENSND_PCM_FORMAT_U8_STR,
>> + .mask = SNDRV_PCM_FMTBIT_U8
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_S8_STR,
>> + .mask = SNDRV_PCM_FMTBIT_S8
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_U16_LE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_U16_LE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_U16_BE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_U16_BE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_S16_LE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_S16_LE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_S16_BE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_S16_BE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_U24_LE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_U24_LE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_U24_BE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_U24_BE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_S24_LE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_S24_LE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_S24_BE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_S24_BE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_U32_LE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_U32_LE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_U32_BE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_U32_BE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_S32_LE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_S32_LE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_S32_BE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_S32_BE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_A_LAW_STR,
>> + .mask = SNDRV_PCM_FMTBIT_A_LAW
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_MU_LAW_STR,
>> + .mask = SNDRV_PCM_FMTBIT_MU_LAW
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_F32_LE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_FLOAT_LE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_F32_BE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_FLOAT_BE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_F64_LE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_FLOAT64_LE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_F64_BE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_FLOAT64_BE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE_STR,
>> + .mask = SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_BE
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_IMA_ADPCM_STR,
>> + .mask = SNDRV_PCM_FMTBIT_IMA_ADPCM
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_MPEG_STR,
>> + .mask = SNDRV_PCM_FMTBIT_MPEG
>> + },
>> + {
>> + .name = XENSND_PCM_FORMAT_GSM_STR,
>> + .mask = SNDRV_PCM_FMTBIT_GSM
>> + },
>> +};
>> +
>> +static void cfg_hw_rates(char *list, unsigned int len,
>> + const char *path, struct snd_pcm_hardware *pcm_hw)
>> +{
>> + char *cur_rate;
>> + unsigned int cur_mask;
>> + unsigned int cur_value;
>> + unsigned int rates;
>> + unsigned int rate_min;
>> + unsigned int rate_max;
>> + int i;
>> +
>> + rates = 0;
>> + rate_min = -1;
>> + rate_max = 0;
>> + while ((cur_rate = strsep(&list, XENSND_LIST_SEPARATOR))) {
>> + for (i = 0; i < ARRAY_SIZE(CFG_HW_SUPPORTED_RATES); i++)
>> + if (!strncasecmp(cur_rate,
>> + CFG_HW_SUPPORTED_RATES[i].name,
>> + XENSND_SAMPLE_RATE_MAX_LEN)) {
>> + cur_mask = CFG_HW_SUPPORTED_RATES[i].mask;
>> + cur_value = CFG_HW_SUPPORTED_RATES[i].value;
>> + rates |= cur_mask;
>> + if (rate_min > cur_value)
>> + rate_min = cur_value;
>> + if (rate_max < cur_value)
>> + rate_max = cur_value;
>> + }
>> + }
>> +
>> + if (rates) {
>> + pcm_hw->rates = rates;
>> + pcm_hw->rate_min = rate_min;
>> + pcm_hw->rate_max = rate_max;
>> + }
>> +}
>> +
>> +static void cfg_formats(char *list, unsigned int len,
>> + const char *path, struct snd_pcm_hardware *pcm_hw)
>> +{
>> + u64 formats;
>> + char *cur_format;
>> + int i;
>> +
>> + formats = 0;
>> + while ((cur_format = strsep(&list, XENSND_LIST_SEPARATOR))) {
>> + for (i = 0; i < ARRAY_SIZE(CFG_HW_SUPPORTED_FORMATS); i++)
>> + if (!strncasecmp(cur_format,
>> + CFG_HW_SUPPORTED_FORMATS[i].name,
>> + XENSND_SAMPLE_FORMAT_MAX_LEN))
>> + formats |= CFG_HW_SUPPORTED_FORMATS[i].mask;
>> + }
>> +
>> + if (formats)
>> + pcm_hw->formats = formats;
>> +}
>> +
>> +#define MAX_BUFFER_SIZE (64 * 1024)
>> +#define MIN_PERIOD_SIZE 64
>> +#define MAX_PERIOD_SIZE MAX_BUFFER_SIZE
>> +#define USE_FORMATS (SNDRV_PCM_FMTBIT_U8 | \
>> + SNDRV_PCM_FMTBIT_S16_LE)
>> +#define USE_RATE (SNDRV_PCM_RATE_CONTINUOUS | \
>> + SNDRV_PCM_RATE_8000_48000)
>> +#define USE_RATE_MIN 5512
>> +#define USE_RATE_MAX 48000
>> +#define USE_CHANNELS_MIN 1
>> +#define USE_CHANNELS_MAX 2
>> +#define USE_PERIODS_MIN 2
>> +#define USE_PERIODS_MAX (MAX_BUFFER_SIZE / MIN_PERIOD_SIZE)
>> +
>> +static const struct snd_pcm_hardware SND_DRV_PCM_HW_DEFAULT = {
>> + .info = (SNDRV_PCM_INFO_MMAP |
>> + SNDRV_PCM_INFO_INTERLEAVED |
>> + SNDRV_PCM_INFO_RESUME |
>> + SNDRV_PCM_INFO_MMAP_VALID),
>> + .formats = USE_FORMATS,
>> + .rates = USE_RATE,
>> + .rate_min = USE_RATE_MIN,
>> + .rate_max = USE_RATE_MAX,
>> + .channels_min = USE_CHANNELS_MIN,
>> + .channels_max = USE_CHANNELS_MAX,
>> + .buffer_bytes_max = MAX_BUFFER_SIZE,
>> + .period_bytes_min = MIN_PERIOD_SIZE,
>> + .period_bytes_max = MAX_PERIOD_SIZE,
>> + .periods_min = USE_PERIODS_MIN,
>> + .periods_max = USE_PERIODS_MAX,
>> + .fifo_size = 0,
>> +};
>> +
>> +static void cfg_read_pcm_hw(const char *path,
>> + struct snd_pcm_hardware *parent_pcm_hw,
>> + struct snd_pcm_hardware *pcm_hw)
>> +{
>> + char *list;
>> + int val;
>> + size_t buf_sz;
>> + unsigned int len;
>> +
>> + /* inherit parent's PCM HW and read overrides from XenStore */
>> + if (parent_pcm_hw)
>> + *pcm_hw = *parent_pcm_hw;
>> + else
>> + *pcm_hw = SND_DRV_PCM_HW_DEFAULT;
>> +
>> + val = xenbus_read_unsigned(path, XENSND_FIELD_CHANNELS_MIN, 0);
>> + if (val)
>> + pcm_hw->channels_min = val;
>> +
>> + val = xenbus_read_unsigned(path, XENSND_FIELD_CHANNELS_MAX, 0);
>> + if (val)
>> + pcm_hw->channels_max = val;
>> +
>> + list = xenbus_read(XBT_NIL, path, XENSND_FIELD_SAMPLE_RATES, &len);
>> + if (!IS_ERR(list)) {
>> + cfg_hw_rates(list, len, path, pcm_hw);
>> + kfree(list);
>> + }
>> +
>> + list = xenbus_read(XBT_NIL, path, XENSND_FIELD_SAMPLE_FORMATS, &len);
>> + if (!IS_ERR(list)) {
>> + cfg_formats(list, len, path, pcm_hw);
>> + kfree(list);
>> + }
>> +
>> + buf_sz = xenbus_read_unsigned(path, XENSND_FIELD_BUFFER_SIZE, 0);
>> + if (buf_sz)
>> + pcm_hw->buffer_bytes_max = buf_sz;
>> +
>> + /* update configuration to match new values */
>> + if (pcm_hw->channels_min > pcm_hw->channels_max)
>> + pcm_hw->channels_min = pcm_hw->channels_max;
>> +
>> + if (pcm_hw->rate_min > pcm_hw->rate_max)
>> + pcm_hw->rate_min = pcm_hw->rate_max;
>> +
>> + pcm_hw->period_bytes_max = pcm_hw->buffer_bytes_max;
>> +
>> + pcm_hw->periods_max = pcm_hw->period_bytes_max /
>> + pcm_hw->period_bytes_min;
>> +}
>> +
>> +static int cfg_get_stream_type(const char *path, int index,
>> + int *num_pb, int *num_cap)
>> +{
>> + char *str = NULL;
>> + char *stream_path;
>> + int ret;
>> +
>> + *num_pb = 0;
>> + *num_cap = 0;
>> + stream_path = kasprintf(GFP_KERNEL, "%s/%d", path, index);
>> + if (!stream_path) {
>> + ret = -ENOMEM;
>> + goto fail;
>> + }
>> +
>> + str = xenbus_read(XBT_NIL, stream_path, XENSND_FIELD_TYPE, NULL);
>> + if (IS_ERR(str)) {
>> + ret = -EINVAL;
> Is this correct? Do you want to return -EINVAL in case xenbus_read()
> failed with e.g. -ENOMEM?
will return PTR_ERR(str)
>> + goto fail;
>> + }
>> +
>> + if (!strncasecmp(str, XENSND_STREAM_TYPE_PLAYBACK,
>> + sizeof(XENSND_STREAM_TYPE_PLAYBACK))) {
>> + (*num_pb)++;
>> + } else if (!strncasecmp(str, XENSND_STREAM_TYPE_CAPTURE,
>> + sizeof(XENSND_STREAM_TYPE_CAPTURE))) {
>> + (*num_cap)++;
>> + } else {
>> + ret = -EINVAL;
>> + goto fail;
>> + }
>> + ret = 0;
>> +
>> +fail:
>> + kfree(stream_path);
>> + kfree(str);
>> + return ret;
>> +}
>> +
>> +static int cfg_stream(struct xen_snd_front_info *front_info,
>> + struct xen_front_cfg_pcm_instance *pcm_instance,
>> + const char *path, int index, int *cur_pb, int *cur_cap,
>> + int *stream_cnt)
>> +{
>> + char *str = NULL;
>> + char *stream_path;
>> + struct xen_front_cfg_stream *stream;
>> + int ret;
>> +
>> + stream_path = devm_kasprintf(&front_info->xb_dev->dev,
>> + GFP_KERNEL, "%s/%d", path, index);
>> + if (!stream_path) {
>> + ret = -ENOMEM;
>> + goto fail;
>> + }
>> +
>> + str = xenbus_read(XBT_NIL, stream_path, XENSND_FIELD_TYPE, NULL);
>> + if (IS_ERR(str)) {
>> + ret = -EINVAL;
> Same as above.
will return PTR_ERR(str)
>
>> + goto fail;
>> + }
>> +
>> + if (!strncasecmp(str, XENSND_STREAM_TYPE_PLAYBACK,
>> + sizeof(XENSND_STREAM_TYPE_PLAYBACK))) {
>> + stream = &pcm_instance->streams_pb[(*cur_pb)++];
>> + } else if (!strncasecmp(str, XENSND_STREAM_TYPE_CAPTURE,
>> + sizeof(XENSND_STREAM_TYPE_CAPTURE))) {
>> + stream = &pcm_instance->streams_cap[(*cur_cap)++];
>> + } else {
>> + ret = -EINVAL;
>> + goto fail;
>> + }
> Until here this function looks very much like cfg_get_stream_type().
> Can't they use a common sub-function?
Not really, because cfg_get_stream_type uses kasprintf
for strings and this one devm_kasprintf. Trying to make
a common sub-func doesn't make sense to me
>
>> +
>> + /* get next stream index */
>> + stream->index = (*stream_cnt)++;
>> + stream->xenstore_path = stream_path;
>> + /*
>> + * check in Xen store if PCM HW configuration exists for this stream
>> + * and update if so, e.g. we inherit all values from device's PCM HW,
>> + * but can still override some of the values for the stream
>> + */
>> + cfg_read_pcm_hw(stream->xenstore_path,
>> + &pcm_instance->pcm_hw, &stream->pcm_hw);
>> + ret = 0;
>> +
>> +fail:
>> + kfree(str);
>> + return ret;
>> +}
>> +
>> +static int cfg_device(struct xen_snd_front_info *front_info,
>> + struct xen_front_cfg_pcm_instance *pcm_instance,
>> + struct snd_pcm_hardware *parent_pcm_hw,
>> + const char *path, int node_index, int *stream_cnt)
>> +{
>> + char *str;
>> + char *device_path;
>> + int ret, i, num_streams;
>> + int num_pb, num_cap;
>> + int cur_pb, cur_cap;
>> + char node[3];
>> +
>> + device_path = kasprintf(GFP_KERNEL, "%s/%d", path, node_index);
>> + if (!device_path)
>> + return -ENOMEM;
>> +
>> + str = xenbus_read(XBT_NIL, device_path, XENSND_FIELD_DEVICE_NAME, NULL);
>> + if (!IS_ERR(str)) {
>> + strncpy(pcm_instance->name, str, sizeof(pcm_instance->name));
>> + kfree(str);
>> + }
>> +
>> + pcm_instance->device_id = node_index;
>> +
>> + /*
>> + * check in Xen store if PCM HW configuration exists for this device
>> + * and update if so, e.g. we inherit all values from card's PCM HW,
>> + * but can still override some of the values for the device
>> + */
>> + cfg_read_pcm_hw(device_path, parent_pcm_hw, &pcm_instance->pcm_hw);
>> +
>> + /* find out how many streams were configured in Xen store */
>> + num_streams = 0;
>> + do {
>> + snprintf(node, sizeof(node), "%d", num_streams);
>> + if (!xenbus_exists(XBT_NIL, device_path, node))
>> + break;
>> +
>> + num_streams++;
>> + } while (num_streams < VSND_MAX_STREAM);
>> +
>> + pcm_instance->num_streams_pb = 0;
>> + pcm_instance->num_streams_cap = 0;
>> + /* get number of playback and capture streams */
>> + for (i = 0; i < num_streams; i++) {
>> + ret = cfg_get_stream_type(device_path, i, &num_pb, &num_cap);
>> + if (ret < 0)
>> + goto fail;
>> +
>> + pcm_instance->num_streams_pb += num_pb;
>> + pcm_instance->num_streams_cap += num_cap;
>> + }
>> +
>> + if (pcm_instance->num_streams_pb) {
>> + pcm_instance->streams_pb =
>> + devm_kcalloc(&front_info->xb_dev->dev,
>> + pcm_instance->num_streams_pb,
>> + sizeof(struct xen_front_cfg_stream),
>> + GFP_KERNEL);
>> + if (!pcm_instance->streams_pb) {
>> + ret = -ENOMEM;
>> + goto fail;
>> + }
>> + }
>> +
>> + if (pcm_instance->num_streams_cap) {
>> + pcm_instance->streams_cap =
>> + devm_kcalloc(&front_info->xb_dev->dev,
>> + pcm_instance->num_streams_cap,
>> + sizeof(struct xen_front_cfg_stream),
>> + GFP_KERNEL);
>> + if (!pcm_instance->streams_cap) {
>> + ret = -ENOMEM;
>> + goto fail;
>> + }
>> + }
>> +
>> + cur_pb = 0;
>> + cur_cap = 0;
>> + for (i = 0; i < num_streams; i++) {
>> + ret = cfg_stream(front_info, pcm_instance, device_path, i,
>> + &cur_pb, &cur_cap, stream_cnt);
>> + if (ret < 0)
>> + goto fail;
>> + }
>> + ret = 0;
>> +
>> +fail:
>> + kfree(device_path);
>> + return ret;
>> +}
>> +
>> +int xen_snd_front_cfg_card(struct xen_snd_front_info *front_info,
>> + int *stream_cnt)
>> +{
>> + struct xenbus_device *xb_dev = front_info->xb_dev;
>> + struct xen_front_cfg_card *cfg = &front_info->cfg;
>> + int ret, num_devices, i;
>> + char node[3];
>> +
>> + *stream_cnt = 0;
>> + num_devices = 0;
>> + do {
>> + snprintf(node, sizeof(node), "%d", num_devices);
>> + if (!xenbus_exists(XBT_NIL, xb_dev->nodename, node))
>> + break;
>> +
>> + num_devices++;
>> + } while (num_devices < SNDRV_PCM_DEVICES);
>> +
>> + if (!num_devices) {
>> + dev_warn(&xb_dev->dev,
>> + "No devices configured for sound card at %s\n",
>> + xb_dev->nodename);
>> + return -ENODEV;
>> + }
>> +
>> + /* start from default PCM HW configuration for the card */
>> + cfg_read_pcm_hw(xb_dev->nodename, NULL, &cfg->pcm_hw);
>> +
>> + cfg->pcm_instances =
>> + devm_kcalloc(&front_info->xb_dev->dev, num_devices,
>> + sizeof(struct xen_front_cfg_pcm_instance),
>> + GFP_KERNEL);
>> + if (!cfg->pcm_instances)
>> + return -ENOMEM;
>> +
>> + for (i = 0; i < num_devices; i++) {
>> + ret = cfg_device(front_info, &cfg->pcm_instances[i],
>> + &cfg->pcm_hw, xb_dev->nodename, i, stream_cnt);
>> + if (ret < 0)
>> + return ret;
> Who will free all the memory allocated until now in case of an error?
The memory is allocated with devm_xxx functions, so it will
be freed on device destructions automatically
>
> And I think when removing the device freeing the memory is missing, too.
Same as above, the kernel will take care of it while destroying the device
>
> Juergen
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling
2018-04-16 13:12 ` Juergen Gross
@ 2018-04-17 8:58 ` Oleksandr Andrushchenko
2018-04-17 11:14 ` Juergen Gross
0 siblings, 1 reply; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-17 8:58 UTC (permalink / raw)
To: Juergen Gross, xen-devel, linux-kernel, alsa-devel,
boris.ostrovsky, konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 04/16/2018 04:12 PM, Juergen Gross wrote:
> On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>
>> Handle Xen event channels:
>> - create for all configured streams and publish
>> corresponding ring references and event channels in Xen store,
>> so backend can connect
>> - implement event channels interrupt handlers
>> - create and destroy event channels with respect to Xen bus state
>>
>> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>> ---
>> sound/xen/Makefile | 3 +-
>> sound/xen/xen_snd_front.c | 10 +-
>> sound/xen/xen_snd_front.h | 7 +
>> sound/xen/xen_snd_front_evtchnl.c | 474 ++++++++++++++++++++++++++++++++++++++
>> sound/xen/xen_snd_front_evtchnl.h | 92 ++++++++
>> 5 files changed, 584 insertions(+), 2 deletions(-)
>> create mode 100644 sound/xen/xen_snd_front_evtchnl.c
>> create mode 100644 sound/xen/xen_snd_front_evtchnl.h
>>
>> diff --git a/sound/xen/Makefile b/sound/xen/Makefile
>> index 06705bef61fa..03c669984000 100644
>> --- a/sound/xen/Makefile
>> +++ b/sound/xen/Makefile
>> @@ -1,6 +1,7 @@
>> # SPDX-License-Identifier: GPL-2.0 OR MIT
>>
>> snd_xen_front-objs := xen_snd_front.o \
>> - xen_snd_front_cfg.o
>> + xen_snd_front_cfg.o \
>> + xen_snd_front_evtchnl.o
>>
>> obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
>> diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
>> index 65d2494a9d14..eb46bf4070f9 100644
>> --- a/sound/xen/xen_snd_front.c
>> +++ b/sound/xen/xen_snd_front.c
>> @@ -18,9 +18,11 @@
>> #include <xen/interface/io/sndif.h>
>>
>> #include "xen_snd_front.h"
>> +#include "xen_snd_front_evtchnl.h"
> Does it really make sense to have multiple driver-private headers?
>
> I think those can be merged.
I would really like to keep it separate as it clearly
shows which stuff belongs to which modules.
At least for me it is easier to maintain it this way.
>
>>
>> static void xen_snd_drv_fini(struct xen_snd_front_info *front_info)
>> {
>> + xen_snd_front_evtchnl_free_all(front_info);
>> }
>>
>> static int sndback_initwait(struct xen_snd_front_info *front_info)
>> @@ -32,7 +34,12 @@ static int sndback_initwait(struct xen_snd_front_info *front_info)
>> if (ret < 0)
>> return ret;
>>
>> - return 0;
>> + /* create event channels for all streams and publish */
>> + ret = xen_snd_front_evtchnl_create_all(front_info, num_streams);
>> + if (ret < 0)
>> + return ret;
>> +
>> + return xen_snd_front_evtchnl_publish_all(front_info);
>> }
>>
>> static int sndback_connect(struct xen_snd_front_info *front_info)
>> @@ -122,6 +129,7 @@ static int xen_drv_probe(struct xenbus_device *xb_dev,
>> return -ENOMEM;
>>
>> front_info->xb_dev = xb_dev;
>> + spin_lock_init(&front_info->io_lock);
>> dev_set_drvdata(&xb_dev->dev, front_info);
>>
>> return xenbus_switch_state(xb_dev, XenbusStateInitialising);
>> diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
>> index b52226cb30bc..9c2ffbb4e4b8 100644
>> --- a/sound/xen/xen_snd_front.h
>> +++ b/sound/xen/xen_snd_front.h
>> @@ -13,9 +13,16 @@
>>
>> #include "xen_snd_front_cfg.h"
>>
>> +struct xen_snd_front_evtchnl_pair;
>> +
>> struct xen_snd_front_info {
>> struct xenbus_device *xb_dev;
>>
>> + /* serializer for backend IO: request/response */
>> + spinlock_t io_lock;
>> + int num_evt_pairs;
>> + struct xen_snd_front_evtchnl_pair *evt_pairs;
>> +
>> struct xen_front_cfg_card cfg;
>> };
>>
>> diff --git a/sound/xen/xen_snd_front_evtchnl.c b/sound/xen/xen_snd_front_evtchnl.c
>> new file mode 100644
>> index 000000000000..9ece39f938f8
>> --- /dev/null
>> +++ b/sound/xen/xen_snd_front_evtchnl.c
>> @@ -0,0 +1,474 @@
>> +// SPDX-License-Identifier: GPL-2.0 OR MIT
>> +
>> +/*
>> + * Xen para-virtual sound device
>> + *
>> + * Copyright (C) 2016-2018 EPAM Systems Inc.
>> + *
>> + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>> + */
>> +
>> +#include <xen/events.h>
>> +#include <xen/grant_table.h>
>> +#include <xen/xen.h>
>> +#include <xen/xenbus.h>
>> +
>> +#include "xen_snd_front.h"
>> +#include "xen_snd_front_cfg.h"
>> +#include "xen_snd_front_evtchnl.h"
>> +
>> +static irqreturn_t evtchnl_interrupt_req(int irq, void *dev_id)
>> +{
>> + struct xen_snd_front_evtchnl *channel = dev_id;
>> + struct xen_snd_front_info *front_info = channel->front_info;
>> + struct xensnd_resp *resp;
>> + RING_IDX i, rp;
>> + unsigned long flags;
>> +
>> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
>> + return IRQ_HANDLED;
>> +
>> + spin_lock_irqsave(&front_info->io_lock, flags);
>> +
>> +again:
>> + rp = channel->u.req.ring.sring->rsp_prod;
>> + /* ensure we see queued responses up to rp */
>> + rmb();
>> +
>> + for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
>> + resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
>> + if (resp->id != channel->evt_id)
>> + continue;
>> + switch (resp->operation) {
>> + case XENSND_OP_OPEN:
>> + /* fall through */
>> + case XENSND_OP_CLOSE:
>> + /* fall through */
>> + case XENSND_OP_READ:
>> + /* fall through */
>> + case XENSND_OP_WRITE:
>> + /* fall through */
>> + case XENSND_OP_TRIGGER:
>> + channel->u.req.resp_status = resp->status;
>> + complete(&channel->u.req.completion);
>> + break;
>> + case XENSND_OP_HW_PARAM_QUERY:
>> + channel->u.req.resp_status = resp->status;
>> + channel->u.req.resp.hw_param =
>> + resp->resp.hw_param;
>> + complete(&channel->u.req.completion);
>> + break;
>> +
>> + default:
>> + dev_err(&front_info->xb_dev->dev,
>> + "Operation %d is not supported\n",
>> + resp->operation);
>> + break;
>> + }
>> + }
>> +
>> + channel->u.req.ring.rsp_cons = i;
>> + if (i != channel->u.req.ring.req_prod_pvt) {
>> + int more_to_do;
>> +
>> + RING_FINAL_CHECK_FOR_RESPONSES(&channel->u.req.ring,
>> + more_to_do);
>> + if (more_to_do)
>> + goto again;
>> + } else {
>> + channel->u.req.ring.sring->rsp_event = i + 1;
>> + }
>> +
>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>> + return IRQ_HANDLED;
>> +}
>> +
>> +static irqreturn_t evtchnl_interrupt_evt(int irq, void *dev_id)
>> +{
>> + struct xen_snd_front_evtchnl *channel = dev_id;
>> + struct xen_snd_front_info *front_info = channel->front_info;
>> + struct xensnd_event_page *page = channel->u.evt.page;
>> + u32 cons, prod;
>> + unsigned long flags;
>> +
>> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
>> + return IRQ_HANDLED;
>> +
>> + spin_lock_irqsave(&front_info->io_lock, flags);
>> +
>> + prod = page->in_prod;
>> + /* ensure we see ring contents up to prod */
>> + virt_rmb();
>> + if (prod == page->in_cons)
>> + goto out;
>> +
>> + for (cons = page->in_cons; cons != prod; cons++) {
>> + struct xensnd_evt *event;
>> +
>> + event = &XENSND_IN_RING_REF(page, cons);
>> + if (unlikely(event->id != channel->evt_id++))
>> + continue;
>> +
>> + switch (event->type) {
>> + case XENSND_EVT_CUR_POS:
>> + /* do nothing at the moment */
>> + break;
>> + }
>> + }
>> +
>> + page->in_cons = cons;
>> + /* ensure ring contents */
>> + virt_wmb();
>> +
>> +out:
>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>> + return IRQ_HANDLED;
>> +}
>> +
>> +void xen_snd_front_evtchnl_flush(struct xen_snd_front_evtchnl *channel)
>> +{
>> + int notify;
>> +
>> + channel->u.req.ring.req_prod_pvt++;
>> + RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&channel->u.req.ring, notify);
>> + if (notify)
>> + notify_remote_via_irq(channel->irq);
>> +}
>> +
>> +static void evtchnl_free(struct xen_snd_front_info *front_info,
>> + struct xen_snd_front_evtchnl *channel)
>> +{
>> + unsigned long page = 0;
>> +
>> + if (channel->type == EVTCHNL_TYPE_REQ)
>> + page = (unsigned long)channel->u.req.ring.sring;
>> + else if (channel->type == EVTCHNL_TYPE_EVT)
>> + page = (unsigned long)channel->u.evt.page;
>> +
>> + if (!page)
>> + return;
>> +
>> + channel->state = EVTCHNL_STATE_DISCONNECTED;
>> + if (channel->type == EVTCHNL_TYPE_REQ) {
>> + /* release all who still waits for response if any */
>> + channel->u.req.resp_status = -EIO;
>> + complete_all(&channel->u.req.completion);
>> + }
>> +
>> + if (channel->irq)
>> + unbind_from_irqhandler(channel->irq, channel);
>> +
>> + if (channel->port)
>> + xenbus_free_evtchn(front_info->xb_dev, channel->port);
>> +
>> + /* end access and free the page */
>> + if (channel->gref != GRANT_INVALID_REF)
>> + gnttab_end_foreign_access(channel->gref, 0, page);
> Free page?
According to [1] if page is provided to gnttab_end_foreign_access
it will be freed. So, no need to free it manually
>> +
>> + memset(channel, 0, sizeof(*channel));
>> +}
>> +
>> +void xen_snd_front_evtchnl_free_all(struct xen_snd_front_info *front_info)
>> +{
>> + int i;
>> +
>> + if (!front_info->evt_pairs)
>> + return;
>> +
>> + for (i = 0; i < front_info->num_evt_pairs; i++) {
>> + evtchnl_free(front_info, &front_info->evt_pairs[i].req);
>> + evtchnl_free(front_info, &front_info->evt_pairs[i].evt);
>> + }
>> +
>> + kfree(front_info->evt_pairs);
>> + front_info->evt_pairs = NULL;
>> +}
>> +
>> +static int evtchnl_alloc(struct xen_snd_front_info *front_info, int index,
>> + struct xen_snd_front_evtchnl *channel,
>> + enum xen_snd_front_evtchnl_type type)
>> +{
>> + struct xenbus_device *xb_dev = front_info->xb_dev;
>> + unsigned long page;
>> + grant_ref_t gref;
>> + irq_handler_t handler;
>> + char *handler_name = NULL;
>> + int ret;
>> +
>> + memset(channel, 0, sizeof(*channel));
>> + channel->type = type;
>> + channel->index = index;
>> + channel->front_info = front_info;
>> + channel->state = EVTCHNL_STATE_DISCONNECTED;
>> + channel->gref = GRANT_INVALID_REF;
>> + page = get_zeroed_page(GFP_NOIO | __GFP_HIGH);
> Why GFP_NOIO | __GFP_HIGH? Could it be you copied that from blkfront
> driver?
It can be net-front, I guess, which has the same for rx/tx rings
> I believe swapping via sound card is rather uncommon.
Indeed, will use GFP_KERNEL here
>> + if (!page) {
>> + ret = -ENOMEM;
>> + goto fail;
>> + }
>> +
>> + handler_name = kasprintf(GFP_KERNEL, "%s-%s", XENSND_DRIVER_NAME,
>> + type == EVTCHNL_TYPE_REQ ?
>> + XENSND_FIELD_RING_REF :
>> + XENSND_FIELD_EVT_RING_REF);
>> + if (!handler_name) {
>> + ret = -ENOMEM;
> Missing free_page(page)? Maybe you rather add it in the common
> fail path instead of the numerous instances below?
>
yes, will move it under the common fail: label
> Juergen
[1]
https://elixir.bootlin.com/linux/v4.17-rc1/source/include/xen/grant_table.h#L96
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 4/5] ALSA: xen-front: Implement handling of shared buffers
2018-04-16 13:39 ` Juergen Gross
@ 2018-04-17 9:22 ` Oleksandr Andrushchenko
2018-04-17 11:15 ` Juergen Gross
0 siblings, 1 reply; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-17 9:22 UTC (permalink / raw)
To: Juergen Gross, xen-devel, linux-kernel, alsa-devel,
boris.ostrovsky, konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 04/16/2018 04:39 PM, Juergen Gross wrote:
> On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>
>> Implement shared buffer handling according to the
>> para-virtualized sound device protocol at xen/interface/io/sndif.h:
>> - manage buffer memory
>> - handle granted references
>> - handle page directories
>>
>> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>> ---
>> sound/xen/Makefile | 3 +-
>> sound/xen/xen_snd_front.c | 8 ++
>> sound/xen/xen_snd_front_shbuf.c | 193 ++++++++++++++++++++++++++++++++++++++++
>> sound/xen/xen_snd_front_shbuf.h | 36 ++++++++
>> 4 files changed, 239 insertions(+), 1 deletion(-)
>> create mode 100644 sound/xen/xen_snd_front_shbuf.c
>> create mode 100644 sound/xen/xen_snd_front_shbuf.h
>>
>> diff --git a/sound/xen/Makefile b/sound/xen/Makefile
>> index 03c669984000..f028bc30af5d 100644
>> --- a/sound/xen/Makefile
>> +++ b/sound/xen/Makefile
>> @@ -2,6 +2,7 @@
>>
>> snd_xen_front-objs := xen_snd_front.o \
>> xen_snd_front_cfg.o \
>> - xen_snd_front_evtchnl.o
>> + xen_snd_front_evtchnl.o \
>> + xen_snd_front_shbuf.o
>>
>> obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
>> diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
>> index eb46bf4070f9..0569c6c596a3 100644
>> --- a/sound/xen/xen_snd_front.c
>> +++ b/sound/xen/xen_snd_front.c
>> @@ -11,6 +11,7 @@
>> #include <linux/delay.h>
>> #include <linux/module.h>
>>
>> +#include <xen/page.h>
>> #include <xen/platform_pci.h>
>> #include <xen/xen.h>
>> #include <xen/xenbus.h>
>> @@ -186,6 +187,13 @@ static struct xenbus_driver xen_driver = {
>>
>> static int __init xen_drv_init(void)
>> {
>> + /* At the moment we only support case with XEN_PAGE_SIZE == PAGE_SIZE */
>> + if (XEN_PAGE_SIZE != PAGE_SIZE) {
>> + pr_err(XENSND_DRIVER_NAME ": different kernel and Xen page sizes are not supported: XEN_PAGE_SIZE (%lu) != PAGE_SIZE (%lu)\n",
>> + XEN_PAGE_SIZE, PAGE_SIZE);
>> + return -ENODEV;
>> + }
> Do you really want to print that error message on bare metal?
will move it down after xen_domain/xen_has_pv_devices checks
>> +
>> if (!xen_domain())
>> return -ENODEV;
>>
>> diff --git a/sound/xen/xen_snd_front_shbuf.c b/sound/xen/xen_snd_front_shbuf.c
>> new file mode 100644
>> index 000000000000..6845dbc7fdf5
>> --- /dev/null
>> +++ b/sound/xen/xen_snd_front_shbuf.c
>> @@ -0,0 +1,193 @@
>> +// SPDX-License-Identifier: GPL-2.0 OR MIT
>> +
>> +/*
>> + * Xen para-virtual sound device
>> + *
>> + * Copyright (C) 2016-2018 EPAM Systems Inc.
>> + *
>> + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>> + */
>> +
>> +#include <xen/xen.h>
>> +#include <xen/xenbus.h>
>> +
>> +#include "xen_snd_front_shbuf.h"
>> +
>> +grant_ref_t xen_snd_front_shbuf_get_dir_start(struct xen_snd_front_shbuf *buf)
>> +{
>> + if (!buf->grefs)
>> + return GRANT_INVALID_REF;
>> +
>> + return buf->grefs[0];
>> +}
>> +
>> +void xen_snd_front_shbuf_clear(struct xen_snd_front_shbuf *buf)
>> +{
>> + memset(buf, 0, sizeof(*buf));
>> +}
>> +
>> +void xen_snd_front_shbuf_free(struct xen_snd_front_shbuf *buf)
>> +{
>> + int i;
>> +
>> + if (buf->grefs) {
>> + for (i = 0; i < buf->num_grefs; i++)
>> + if (buf->grefs[i] != GRANT_INVALID_REF)
>> + gnttab_end_foreign_access(buf->grefs[i],
>> + 0, 0UL);
>> + kfree(buf->grefs);
>> + }
>> + kfree(buf->directory);
>> + free_pages_exact(buf->buffer, buf->buffer_sz);
>> + xen_snd_front_shbuf_clear(buf);
>> +}
>> +
>> +/*
>> + * number of grant references a page can hold with respect to the
>> + * xensnd_page_directory header
>> + */
>> +#define XENSND_NUM_GREFS_PER_PAGE ((XEN_PAGE_SIZE - \
>> + offsetof(struct xensnd_page_directory, gref)) / \
>> + sizeof(grant_ref_t))
>> +
>> +static void fill_page_dir(struct xen_snd_front_shbuf *buf,
>> + int num_pages_dir)
>> +{
>> + struct xensnd_page_directory *page_dir;
>> + unsigned char *ptr;
>> + int i, cur_gref, grefs_left, to_copy;
>> +
>> + ptr = buf->directory;
>> + grefs_left = buf->num_grefs - num_pages_dir;
>> + /*
>> + * skip grant references at the beginning, they are for pages granted
>> + * for the page directory itself
>> + */
>> + cur_gref = num_pages_dir;
>> + for (i = 0; i < num_pages_dir; i++) {
>> + page_dir = (struct xensnd_page_directory *)ptr;
>> + if (grefs_left <= XENSND_NUM_GREFS_PER_PAGE) {
>> + to_copy = grefs_left;
>> + page_dir->gref_dir_next_page = GRANT_INVALID_REF;
>> + } else {
>> + to_copy = XENSND_NUM_GREFS_PER_PAGE;
>> + page_dir->gref_dir_next_page = buf->grefs[i + 1];
>> + }
>> +
>> + memcpy(&page_dir->gref, &buf->grefs[cur_gref],
>> + to_copy * sizeof(grant_ref_t));
>> +
>> + ptr += XEN_PAGE_SIZE;
>> + grefs_left -= to_copy;
>> + cur_gref += to_copy;
>> + }
>> +}
>> +
>> +static int grant_references(struct xenbus_device *xb_dev,
>> + struct xen_snd_front_shbuf *buf,
>> + int num_pages_dir, int num_pages_buffer,
>> + int num_grefs)
>> +{
>> + grant_ref_t priv_gref_head;
>> + unsigned long frame;
>> + int ret, i, j, cur_ref;
>> + int otherend_id;
>> +
>> + ret = gnttab_alloc_grant_references(num_grefs, &priv_gref_head);
>> + if (ret)
>> + return ret;
>> +
>> + buf->num_grefs = num_grefs;
>> + otherend_id = xb_dev->otherend_id;
>> + j = 0;
>> +
>> + for (i = 0; i < num_pages_dir; i++) {
>> + cur_ref = gnttab_claim_grant_reference(&priv_gref_head);
>> + if (cur_ref < 0) {
>> + ret = cur_ref;
>> + goto fail;
>> + }
>> +
>> + frame = xen_page_to_gfn(virt_to_page(buf->directory +
>> + XEN_PAGE_SIZE * i));
>> + gnttab_grant_foreign_access_ref(cur_ref, otherend_id, frame, 0);
>> + buf->grefs[j++] = cur_ref;
>> + }
>> +
>> + for (i = 0; i < num_pages_buffer; i++) {
>> + cur_ref = gnttab_claim_grant_reference(&priv_gref_head);
>> + if (cur_ref < 0) {
>> + ret = cur_ref;
>> + goto fail;
>> + }
>> +
>> + frame = xen_page_to_gfn(virt_to_page(buf->buffer +
>> + XEN_PAGE_SIZE * i));
>> + gnttab_grant_foreign_access_ref(cur_ref, otherend_id, frame, 0);
>> + buf->grefs[j++] = cur_ref;
>> + }
>> +
>> + gnttab_free_grant_references(priv_gref_head);
>> + fill_page_dir(buf, num_pages_dir);
>> + return 0;
>> +
>> +fail:
>> + gnttab_free_grant_references(priv_gref_head);
>> + return ret;
>> +}
>> +
>> +static int alloc_int_buffers(struct xen_snd_front_shbuf *buf,
>> + int num_pages_dir, int num_pages_buffer,
>> + int num_grefs)
>> +{
>> + buf->grefs = kcalloc(num_grefs, sizeof(*buf->grefs), GFP_KERNEL);
>> + if (!buf->grefs)
>> + return -ENOMEM;
>> +
>> + buf->directory = kcalloc(num_pages_dir, XEN_PAGE_SIZE, GFP_KERNEL);
>> + if (!buf->directory)
>> + goto fail;
>> +
>> + buf->buffer_sz = num_pages_buffer * XEN_PAGE_SIZE;
>> + buf->buffer = alloc_pages_exact(buf->buffer_sz, GFP_KERNEL);
>> + if (!buf->buffer)
>> + goto fail;
>> +
>> + return 0;
>> +
>> +fail:
>> + kfree(buf->grefs);
>> + buf->grefs = NULL;
>> + kfree(buf->directory);
> Why do you need to free those here? Shouldn't that be done via
> xen_snd_front_shbuf_free() in case of an error?
At this place we only allocate memory, but xen_snd_front_shbuf_free
will also try to gnttab_end_foreign_access if buf->grefs != NULL.
> Juergen
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 2/5] ALSA: xen-front: Read sound driver configuration from Xen store
2018-04-17 8:42 ` Oleksandr Andrushchenko
@ 2018-04-17 11:08 ` Juergen Gross
0 siblings, 0 replies; 40+ messages in thread
From: Juergen Gross @ 2018-04-17 11:08 UTC (permalink / raw)
To: Oleksandr Andrushchenko, xen-devel, linux-kernel, alsa-devel,
boris.ostrovsky, konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 17/04/18 10:42, Oleksandr Andrushchenko wrote:
> On 04/16/2018 03:55 PM, Juergen Gross wrote:
>> On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
>>> + goto fail;
>>> + }
>>> +
>>> + if (!strncasecmp(str, XENSND_STREAM_TYPE_PLAYBACK,
>>> + sizeof(XENSND_STREAM_TYPE_PLAYBACK))) {
>>> + stream = &pcm_instance->streams_pb[(*cur_pb)++];
>>> + } else if (!strncasecmp(str, XENSND_STREAM_TYPE_CAPTURE,
>>> + sizeof(XENSND_STREAM_TYPE_CAPTURE))) {
>>> + stream = &pcm_instance->streams_cap[(*cur_cap)++];
>>> + } else {
>>> + ret = -EINVAL;
>>> + goto fail;
>>> + }
>> Until here this function looks very much like cfg_get_stream_type().
>> Can't they use a common sub-function?
> Not really, because cfg_get_stream_type uses kasprintf
> for strings and this one devm_kasprintf. Trying to make
> a common sub-func doesn't make sense to me
Aah, okay. Didn't spot that.
>>> + /* start from default PCM HW configuration for the card */
>>> + cfg_read_pcm_hw(xb_dev->nodename, NULL, &cfg->pcm_hw);
>>> +
>>> + cfg->pcm_instances =
>>> + devm_kcalloc(&front_info->xb_dev->dev, num_devices,
>>> + sizeof(struct xen_front_cfg_pcm_instance),
>>> + GFP_KERNEL);
>>> + if (!cfg->pcm_instances)
>>> + return -ENOMEM;
>>> +
>>> + for (i = 0; i < num_devices; i++) {
>>> + ret = cfg_device(front_info, &cfg->pcm_instances[i],
>>> + &cfg->pcm_hw, xb_dev->nodename, i, stream_cnt);
>>> + if (ret < 0)
>>> + return ret;
>> Who will free all the memory allocated until now in case of an error?
> The memory is allocated with devm_xxx functions, so it will
> be freed on device destructions automatically
>>
>> And I think when removing the device freeing the memory is missing, too.
> Same as above, the kernel will take care of it while destroying the device
Okay, thanks.
Juergen
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling
2018-04-17 8:58 ` Oleksandr Andrushchenko
@ 2018-04-17 11:14 ` Juergen Gross
2018-04-17 11:21 ` Oleksandr Andrushchenko
0 siblings, 1 reply; 40+ messages in thread
From: Juergen Gross @ 2018-04-17 11:14 UTC (permalink / raw)
To: Oleksandr Andrushchenko, xen-devel, linux-kernel, alsa-devel,
boris.ostrovsky, konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 17/04/18 10:58, Oleksandr Andrushchenko wrote:
> On 04/16/2018 04:12 PM, Juergen Gross wrote:
>> On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
>>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>>
>>> Handle Xen event channels:
>>> - create for all configured streams and publish
>>> corresponding ring references and event channels in Xen store,
>>> so backend can connect
>>> - implement event channels interrupt handlers
>>> - create and destroy event channels with respect to Xen bus state
>>>
>>> Signed-off-by: Oleksandr Andrushchenko
>>> <oleksandr_andrushchenko@epam.com>
>>> ---
>>> sound/xen/Makefile | 3 +-
>>> sound/xen/xen_snd_front.c | 10 +-
>>> sound/xen/xen_snd_front.h | 7 +
>>> sound/xen/xen_snd_front_evtchnl.c | 474
>>> ++++++++++++++++++++++++++++++++++++++
>>> sound/xen/xen_snd_front_evtchnl.h | 92 ++++++++
>>> 5 files changed, 584 insertions(+), 2 deletions(-)
>>> create mode 100644 sound/xen/xen_snd_front_evtchnl.c
>>> create mode 100644 sound/xen/xen_snd_front_evtchnl.h
>>>
>>> diff --git a/sound/xen/Makefile b/sound/xen/Makefile
>>> index 06705bef61fa..03c669984000 100644
>>> --- a/sound/xen/Makefile
>>> +++ b/sound/xen/Makefile
>>> @@ -1,6 +1,7 @@
>>> # SPDX-License-Identifier: GPL-2.0 OR MIT
>>> snd_xen_front-objs := xen_snd_front.o \
>>> - xen_snd_front_cfg.o
>>> + xen_snd_front_cfg.o \
>>> + xen_snd_front_evtchnl.o
>>> obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
>>> diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
>>> index 65d2494a9d14..eb46bf4070f9 100644
>>> --- a/sound/xen/xen_snd_front.c
>>> +++ b/sound/xen/xen_snd_front.c
>>> @@ -18,9 +18,11 @@
>>> #include <xen/interface/io/sndif.h>
>>> #include "xen_snd_front.h"
>>> +#include "xen_snd_front_evtchnl.h"
>> Does it really make sense to have multiple driver-private headers?
>>
>> I think those can be merged.
> I would really like to keep it separate as it clearly
> shows which stuff belongs to which modules.
> At least for me it is easier to maintain it this way.
>>
>>> static void xen_snd_drv_fini(struct xen_snd_front_info *front_info)
>>> {
>>> + xen_snd_front_evtchnl_free_all(front_info);
>>> }
>>> static int sndback_initwait(struct xen_snd_front_info *front_info)
>>> @@ -32,7 +34,12 @@ static int sndback_initwait(struct
>>> xen_snd_front_info *front_info)
>>> if (ret < 0)
>>> return ret;
>>> - return 0;
>>> + /* create event channels for all streams and publish */
>>> + ret = xen_snd_front_evtchnl_create_all(front_info, num_streams);
>>> + if (ret < 0)
>>> + return ret;
>>> +
>>> + return xen_snd_front_evtchnl_publish_all(front_info);
>>> }
>>> static int sndback_connect(struct xen_snd_front_info *front_info)
>>> @@ -122,6 +129,7 @@ static int xen_drv_probe(struct xenbus_device
>>> *xb_dev,
>>> return -ENOMEM;
>>> front_info->xb_dev = xb_dev;
>>> + spin_lock_init(&front_info->io_lock);
>>> dev_set_drvdata(&xb_dev->dev, front_info);
>>> return xenbus_switch_state(xb_dev, XenbusStateInitialising);
>>> diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
>>> index b52226cb30bc..9c2ffbb4e4b8 100644
>>> --- a/sound/xen/xen_snd_front.h
>>> +++ b/sound/xen/xen_snd_front.h
>>> @@ -13,9 +13,16 @@
>>> #include "xen_snd_front_cfg.h"
>>> +struct xen_snd_front_evtchnl_pair;
>>> +
>>> struct xen_snd_front_info {
>>> struct xenbus_device *xb_dev;
>>> + /* serializer for backend IO: request/response */
>>> + spinlock_t io_lock;
>>> + int num_evt_pairs;
>>> + struct xen_snd_front_evtchnl_pair *evt_pairs;
>>> +
>>> struct xen_front_cfg_card cfg;
>>> };
>>> diff --git a/sound/xen/xen_snd_front_evtchnl.c
>>> b/sound/xen/xen_snd_front_evtchnl.c
>>> new file mode 100644
>>> index 000000000000..9ece39f938f8
>>> --- /dev/null
>>> +++ b/sound/xen/xen_snd_front_evtchnl.c
>>> @@ -0,0 +1,474 @@
>>> +// SPDX-License-Identifier: GPL-2.0 OR MIT
>>> +
>>> +/*
>>> + * Xen para-virtual sound device
>>> + *
>>> + * Copyright (C) 2016-2018 EPAM Systems Inc.
>>> + *
>>> + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>> + */
>>> +
>>> +#include <xen/events.h>
>>> +#include <xen/grant_table.h>
>>> +#include <xen/xen.h>
>>> +#include <xen/xenbus.h>
>>> +
>>> +#include "xen_snd_front.h"
>>> +#include "xen_snd_front_cfg.h"
>>> +#include "xen_snd_front_evtchnl.h"
>>> +
>>> +static irqreturn_t evtchnl_interrupt_req(int irq, void *dev_id)
>>> +{
>>> + struct xen_snd_front_evtchnl *channel = dev_id;
>>> + struct xen_snd_front_info *front_info = channel->front_info;
>>> + struct xensnd_resp *resp;
>>> + RING_IDX i, rp;
>>> + unsigned long flags;
>>> +
>>> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
>>> + return IRQ_HANDLED;
>>> +
>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>> +
>>> +again:
>>> + rp = channel->u.req.ring.sring->rsp_prod;
>>> + /* ensure we see queued responses up to rp */
>>> + rmb();
>>> +
>>> + for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
>>> + resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
>>> + if (resp->id != channel->evt_id)
>>> + continue;
>>> + switch (resp->operation) {
>>> + case XENSND_OP_OPEN:
>>> + /* fall through */
>>> + case XENSND_OP_CLOSE:
>>> + /* fall through */
>>> + case XENSND_OP_READ:
>>> + /* fall through */
>>> + case XENSND_OP_WRITE:
>>> + /* fall through */
>>> + case XENSND_OP_TRIGGER:
>>> + channel->u.req.resp_status = resp->status;
>>> + complete(&channel->u.req.completion);
>>> + break;
>>> + case XENSND_OP_HW_PARAM_QUERY:
>>> + channel->u.req.resp_status = resp->status;
>>> + channel->u.req.resp.hw_param =
>>> + resp->resp.hw_param;
>>> + complete(&channel->u.req.completion);
>>> + break;
>>> +
>>> + default:
>>> + dev_err(&front_info->xb_dev->dev,
>>> + "Operation %d is not supported\n",
>>> + resp->operation);
>>> + break;
>>> + }
>>> + }
>>> +
>>> + channel->u.req.ring.rsp_cons = i;
>>> + if (i != channel->u.req.ring.req_prod_pvt) {
>>> + int more_to_do;
>>> +
>>> + RING_FINAL_CHECK_FOR_RESPONSES(&channel->u.req.ring,
>>> + more_to_do);
>>> + if (more_to_do)
>>> + goto again;
>>> + } else {
>>> + channel->u.req.ring.sring->rsp_event = i + 1;
>>> + }
>>> +
>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>> + return IRQ_HANDLED;
>>> +}
>>> +
>>> +static irqreturn_t evtchnl_interrupt_evt(int irq, void *dev_id)
>>> +{
>>> + struct xen_snd_front_evtchnl *channel = dev_id;
>>> + struct xen_snd_front_info *front_info = channel->front_info;
>>> + struct xensnd_event_page *page = channel->u.evt.page;
>>> + u32 cons, prod;
>>> + unsigned long flags;
>>> +
>>> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
>>> + return IRQ_HANDLED;
>>> +
>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>> +
>>> + prod = page->in_prod;
>>> + /* ensure we see ring contents up to prod */
>>> + virt_rmb();
>>> + if (prod == page->in_cons)
>>> + goto out;
>>> +
>>> + for (cons = page->in_cons; cons != prod; cons++) {
>>> + struct xensnd_evt *event;
>>> +
>>> + event = &XENSND_IN_RING_REF(page, cons);
>>> + if (unlikely(event->id != channel->evt_id++))
>>> + continue;
>>> +
>>> + switch (event->type) {
>>> + case XENSND_EVT_CUR_POS:
>>> + /* do nothing at the moment */
>>> + break;
>>> + }
>>> + }
>>> +
>>> + page->in_cons = cons;
>>> + /* ensure ring contents */
>>> + virt_wmb();
>>> +
>>> +out:
>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>> + return IRQ_HANDLED;
>>> +}
>>> +
>>> +void xen_snd_front_evtchnl_flush(struct xen_snd_front_evtchnl *channel)
>>> +{
>>> + int notify;
>>> +
>>> + channel->u.req.ring.req_prod_pvt++;
>>> + RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&channel->u.req.ring, notify);
>>> + if (notify)
>>> + notify_remote_via_irq(channel->irq);
>>> +}
>>> +
>>> +static void evtchnl_free(struct xen_snd_front_info *front_info,
>>> + struct xen_snd_front_evtchnl *channel)
>>> +{
>>> + unsigned long page = 0;
>>> +
>>> + if (channel->type == EVTCHNL_TYPE_REQ)
>>> + page = (unsigned long)channel->u.req.ring.sring;
>>> + else if (channel->type == EVTCHNL_TYPE_EVT)
>>> + page = (unsigned long)channel->u.evt.page;
>>> +
>>> + if (!page)
>>> + return;
>>> +
>>> + channel->state = EVTCHNL_STATE_DISCONNECTED;
>>> + if (channel->type == EVTCHNL_TYPE_REQ) {
>>> + /* release all who still waits for response if any */
>>> + channel->u.req.resp_status = -EIO;
>>> + complete_all(&channel->u.req.completion);
>>> + }
>>> +
>>> + if (channel->irq)
>>> + unbind_from_irqhandler(channel->irq, channel);
>>> +
>>> + if (channel->port)
>>> + xenbus_free_evtchn(front_info->xb_dev, channel->port);
>>> +
>>> + /* end access and free the page */
>>> + if (channel->gref != GRANT_INVALID_REF)
>>> + gnttab_end_foreign_access(channel->gref, 0, page);
>> Free page?
> According to [1] if page is provided to gnttab_end_foreign_access
> it will be freed. So, no need to free it manually
Either a free_page() is missing here in an else clause or the if is
not necessary.
Juergen
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 4/5] ALSA: xen-front: Implement handling of shared buffers
2018-04-17 9:22 ` Oleksandr Andrushchenko
@ 2018-04-17 11:15 ` Juergen Gross
0 siblings, 0 replies; 40+ messages in thread
From: Juergen Gross @ 2018-04-17 11:15 UTC (permalink / raw)
To: Oleksandr Andrushchenko, xen-devel, linux-kernel, alsa-devel,
boris.ostrovsky, konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 17/04/18 11:22, Oleksandr Andrushchenko wrote:
> On 04/16/2018 04:39 PM, Juergen Gross wrote:
>> On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
>>> +static int alloc_int_buffers(struct xen_snd_front_shbuf *buf,
>>> + int num_pages_dir, int num_pages_buffer,
>>> + int num_grefs)
>>> +{
>>> + buf->grefs = kcalloc(num_grefs, sizeof(*buf->grefs), GFP_KERNEL);
>>> + if (!buf->grefs)
>>> + return -ENOMEM;
>>> +
>>> + buf->directory = kcalloc(num_pages_dir, XEN_PAGE_SIZE, GFP_KERNEL);
>>> + if (!buf->directory)
>>> + goto fail;
>>> +
>>> + buf->buffer_sz = num_pages_buffer * XEN_PAGE_SIZE;
>>> + buf->buffer = alloc_pages_exact(buf->buffer_sz, GFP_KERNEL);
>>> + if (!buf->buffer)
>>> + goto fail;
>>> +
>>> + return 0;
>>> +
>>> +fail:
>>> + kfree(buf->grefs);
>>> + buf->grefs = NULL;
>>> + kfree(buf->directory);
>> Why do you need to free those here? Shouldn't that be done via
>> xen_snd_front_shbuf_free() in case of an error?
> At this place we only allocate memory, but xen_snd_front_shbuf_free
> will also try to gnttab_end_foreign_access if buf->grefs != NULL.
Okay.
Juergen
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling
2018-04-17 11:14 ` Juergen Gross
@ 2018-04-17 11:21 ` Oleksandr Andrushchenko
0 siblings, 0 replies; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-17 11:21 UTC (permalink / raw)
To: Juergen Gross, xen-devel, linux-kernel, alsa-devel,
boris.ostrovsky, konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 04/17/2018 02:14 PM, Juergen Gross wrote:
> On 17/04/18 10:58, Oleksandr Andrushchenko wrote:
>> On 04/16/2018 04:12 PM, Juergen Gross wrote:
>>> On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
>>>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>>>
>>>> Handle Xen event channels:
>>>> - create for all configured streams and publish
>>>> corresponding ring references and event channels in Xen store,
>>>> so backend can connect
>>>> - implement event channels interrupt handlers
>>>> - create and destroy event channels with respect to Xen bus state
>>>>
>>>> Signed-off-by: Oleksandr Andrushchenko
>>>> <oleksandr_andrushchenko@epam.com>
>>>> ---
>>>> sound/xen/Makefile | 3 +-
>>>> sound/xen/xen_snd_front.c | 10 +-
>>>> sound/xen/xen_snd_front.h | 7 +
>>>> sound/xen/xen_snd_front_evtchnl.c | 474
>>>> ++++++++++++++++++++++++++++++++++++++
>>>> sound/xen/xen_snd_front_evtchnl.h | 92 ++++++++
>>>> 5 files changed, 584 insertions(+), 2 deletions(-)
>>>> create mode 100644 sound/xen/xen_snd_front_evtchnl.c
>>>> create mode 100644 sound/xen/xen_snd_front_evtchnl.h
>>>>
>>>> diff --git a/sound/xen/Makefile b/sound/xen/Makefile
>>>> index 06705bef61fa..03c669984000 100644
>>>> --- a/sound/xen/Makefile
>>>> +++ b/sound/xen/Makefile
>>>> @@ -1,6 +1,7 @@
>>>> # SPDX-License-Identifier: GPL-2.0 OR MIT
>>>> snd_xen_front-objs := xen_snd_front.o \
>>>> - xen_snd_front_cfg.o
>>>> + xen_snd_front_cfg.o \
>>>> + xen_snd_front_evtchnl.o
>>>> obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
>>>> diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
>>>> index 65d2494a9d14..eb46bf4070f9 100644
>>>> --- a/sound/xen/xen_snd_front.c
>>>> +++ b/sound/xen/xen_snd_front.c
>>>> @@ -18,9 +18,11 @@
>>>> #include <xen/interface/io/sndif.h>
>>>> #include "xen_snd_front.h"
>>>> +#include "xen_snd_front_evtchnl.h"
>>> Does it really make sense to have multiple driver-private headers?
>>>
>>> I think those can be merged.
>> I would really like to keep it separate as it clearly
>> shows which stuff belongs to which modules.
>> At least for me it is easier to maintain it this way.
>>>> static void xen_snd_drv_fini(struct xen_snd_front_info *front_info)
>>>> {
>>>> + xen_snd_front_evtchnl_free_all(front_info);
>>>> }
>>>> static int sndback_initwait(struct xen_snd_front_info *front_info)
>>>> @@ -32,7 +34,12 @@ static int sndback_initwait(struct
>>>> xen_snd_front_info *front_info)
>>>> if (ret < 0)
>>>> return ret;
>>>> - return 0;
>>>> + /* create event channels for all streams and publish */
>>>> + ret = xen_snd_front_evtchnl_create_all(front_info, num_streams);
>>>> + if (ret < 0)
>>>> + return ret;
>>>> +
>>>> + return xen_snd_front_evtchnl_publish_all(front_info);
>>>> }
>>>> static int sndback_connect(struct xen_snd_front_info *front_info)
>>>> @@ -122,6 +129,7 @@ static int xen_drv_probe(struct xenbus_device
>>>> *xb_dev,
>>>> return -ENOMEM;
>>>> front_info->xb_dev = xb_dev;
>>>> + spin_lock_init(&front_info->io_lock);
>>>> dev_set_drvdata(&xb_dev->dev, front_info);
>>>> return xenbus_switch_state(xb_dev, XenbusStateInitialising);
>>>> diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
>>>> index b52226cb30bc..9c2ffbb4e4b8 100644
>>>> --- a/sound/xen/xen_snd_front.h
>>>> +++ b/sound/xen/xen_snd_front.h
>>>> @@ -13,9 +13,16 @@
>>>> #include "xen_snd_front_cfg.h"
>>>> +struct xen_snd_front_evtchnl_pair;
>>>> +
>>>> struct xen_snd_front_info {
>>>> struct xenbus_device *xb_dev;
>>>> + /* serializer for backend IO: request/response */
>>>> + spinlock_t io_lock;
>>>> + int num_evt_pairs;
>>>> + struct xen_snd_front_evtchnl_pair *evt_pairs;
>>>> +
>>>> struct xen_front_cfg_card cfg;
>>>> };
>>>> diff --git a/sound/xen/xen_snd_front_evtchnl.c
>>>> b/sound/xen/xen_snd_front_evtchnl.c
>>>> new file mode 100644
>>>> index 000000000000..9ece39f938f8
>>>> --- /dev/null
>>>> +++ b/sound/xen/xen_snd_front_evtchnl.c
>>>> @@ -0,0 +1,474 @@
>>>> +// SPDX-License-Identifier: GPL-2.0 OR MIT
>>>> +
>>>> +/*
>>>> + * Xen para-virtual sound device
>>>> + *
>>>> + * Copyright (C) 2016-2018 EPAM Systems Inc.
>>>> + *
>>>> + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>>> + */
>>>> +
>>>> +#include <xen/events.h>
>>>> +#include <xen/grant_table.h>
>>>> +#include <xen/xen.h>
>>>> +#include <xen/xenbus.h>
>>>> +
>>>> +#include "xen_snd_front.h"
>>>> +#include "xen_snd_front_cfg.h"
>>>> +#include "xen_snd_front_evtchnl.h"
>>>> +
>>>> +static irqreturn_t evtchnl_interrupt_req(int irq, void *dev_id)
>>>> +{
>>>> + struct xen_snd_front_evtchnl *channel = dev_id;
>>>> + struct xen_snd_front_info *front_info = channel->front_info;
>>>> + struct xensnd_resp *resp;
>>>> + RING_IDX i, rp;
>>>> + unsigned long flags;
>>>> +
>>>> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
>>>> + return IRQ_HANDLED;
>>>> +
>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>> +
>>>> +again:
>>>> + rp = channel->u.req.ring.sring->rsp_prod;
>>>> + /* ensure we see queued responses up to rp */
>>>> + rmb();
>>>> +
>>>> + for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
>>>> + resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
>>>> + if (resp->id != channel->evt_id)
>>>> + continue;
>>>> + switch (resp->operation) {
>>>> + case XENSND_OP_OPEN:
>>>> + /* fall through */
>>>> + case XENSND_OP_CLOSE:
>>>> + /* fall through */
>>>> + case XENSND_OP_READ:
>>>> + /* fall through */
>>>> + case XENSND_OP_WRITE:
>>>> + /* fall through */
>>>> + case XENSND_OP_TRIGGER:
>>>> + channel->u.req.resp_status = resp->status;
>>>> + complete(&channel->u.req.completion);
>>>> + break;
>>>> + case XENSND_OP_HW_PARAM_QUERY:
>>>> + channel->u.req.resp_status = resp->status;
>>>> + channel->u.req.resp.hw_param =
>>>> + resp->resp.hw_param;
>>>> + complete(&channel->u.req.completion);
>>>> + break;
>>>> +
>>>> + default:
>>>> + dev_err(&front_info->xb_dev->dev,
>>>> + "Operation %d is not supported\n",
>>>> + resp->operation);
>>>> + break;
>>>> + }
>>>> + }
>>>> +
>>>> + channel->u.req.ring.rsp_cons = i;
>>>> + if (i != channel->u.req.ring.req_prod_pvt) {
>>>> + int more_to_do;
>>>> +
>>>> + RING_FINAL_CHECK_FOR_RESPONSES(&channel->u.req.ring,
>>>> + more_to_do);
>>>> + if (more_to_do)
>>>> + goto again;
>>>> + } else {
>>>> + channel->u.req.ring.sring->rsp_event = i + 1;
>>>> + }
>>>> +
>>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>>> + return IRQ_HANDLED;
>>>> +}
>>>> +
>>>> +static irqreturn_t evtchnl_interrupt_evt(int irq, void *dev_id)
>>>> +{
>>>> + struct xen_snd_front_evtchnl *channel = dev_id;
>>>> + struct xen_snd_front_info *front_info = channel->front_info;
>>>> + struct xensnd_event_page *page = channel->u.evt.page;
>>>> + u32 cons, prod;
>>>> + unsigned long flags;
>>>> +
>>>> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
>>>> + return IRQ_HANDLED;
>>>> +
>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>> +
>>>> + prod = page->in_prod;
>>>> + /* ensure we see ring contents up to prod */
>>>> + virt_rmb();
>>>> + if (prod == page->in_cons)
>>>> + goto out;
>>>> +
>>>> + for (cons = page->in_cons; cons != prod; cons++) {
>>>> + struct xensnd_evt *event;
>>>> +
>>>> + event = &XENSND_IN_RING_REF(page, cons);
>>>> + if (unlikely(event->id != channel->evt_id++))
>>>> + continue;
>>>> +
>>>> + switch (event->type) {
>>>> + case XENSND_EVT_CUR_POS:
>>>> + /* do nothing at the moment */
>>>> + break;
>>>> + }
>>>> + }
>>>> +
>>>> + page->in_cons = cons;
>>>> + /* ensure ring contents */
>>>> + virt_wmb();
>>>> +
>>>> +out:
>>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>>> + return IRQ_HANDLED;
>>>> +}
>>>> +
>>>> +void xen_snd_front_evtchnl_flush(struct xen_snd_front_evtchnl *channel)
>>>> +{
>>>> + int notify;
>>>> +
>>>> + channel->u.req.ring.req_prod_pvt++;
>>>> + RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&channel->u.req.ring, notify);
>>>> + if (notify)
>>>> + notify_remote_via_irq(channel->irq);
>>>> +}
>>>> +
>>>> +static void evtchnl_free(struct xen_snd_front_info *front_info,
>>>> + struct xen_snd_front_evtchnl *channel)
>>>> +{
>>>> + unsigned long page = 0;
>>>> +
>>>> + if (channel->type == EVTCHNL_TYPE_REQ)
>>>> + page = (unsigned long)channel->u.req.ring.sring;
>>>> + else if (channel->type == EVTCHNL_TYPE_EVT)
>>>> + page = (unsigned long)channel->u.evt.page;
>>>> +
>>>> + if (!page)
>>>> + return;
>>>> +
>>>> + channel->state = EVTCHNL_STATE_DISCONNECTED;
>>>> + if (channel->type == EVTCHNL_TYPE_REQ) {
>>>> + /* release all who still waits for response if any */
>>>> + channel->u.req.resp_status = -EIO;
>>>> + complete_all(&channel->u.req.completion);
>>>> + }
>>>> +
>>>> + if (channel->irq)
>>>> + unbind_from_irqhandler(channel->irq, channel);
>>>> +
>>>> + if (channel->port)
>>>> + xenbus_free_evtchn(front_info->xb_dev, channel->port);
>>>> +
>>>> + /* end access and free the page */
>>>> + if (channel->gref != GRANT_INVALID_REF)
>>>> + gnttab_end_foreign_access(channel->gref, 0, page);
>>> Free page?
>> According to [1] if page is provided to gnttab_end_foreign_access
>> it will be freed. So, no need to free it manually
> Either a free_page() is missing here in an else clause or the if is
> not necessary.
Good catch ;) I need else + free_page, because I won't be able
to end access for invalid grant ref.
Thank you
>
> Juergen
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 5/5] ALSA: xen-front: Implement ALSA virtual sound driver
2018-04-16 14:09 ` Juergen Gross
@ 2018-04-17 11:32 ` Oleksandr Andrushchenko
2018-04-17 12:26 ` Oleksandr Andrushchenko
0 siblings, 1 reply; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-17 11:32 UTC (permalink / raw)
To: Juergen Gross, xen-devel, linux-kernel, alsa-devel,
boris.ostrovsky, konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 04/16/2018 05:09 PM, Juergen Gross wrote:
> On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>
>> Implement essential initialization of the sound driver:
>> - introduce required data structures
>> - handle driver registration
>> - handle sound card registration
>> - register sound driver on backend connection
>> - remove sound driver on backend disconnect
>>
>> Initialize virtual sound card with streams according to the
>> Xen store configuration.
>>
>> Implement ALSA driver operations including:
>> - manage frontend/backend shared buffers
>> - manage Xen bus event channel states
>>
>> Implement requests from front to back for ALSA
>> PCM operations.
>> - report ALSA period elapsed event: handle XENSND_EVT_CUR_POS
>> notifications from the backend when stream position advances
>> during playback/capture. The event carries a value of how
>> many octets were played/captured at the time of the event.
>> - implement explicit stream parameter negotiation between
>> backend and frontend: handle XENSND_OP_HW_PARAM_QUERY request
>> to read/update configuration space for the parameter given:
>> request passes desired parameter interval and the response to
>> this request returns min/max interval for the parameter to be used.
>>
>> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>> ---
>> sound/xen/Makefile | 3 +-
>> sound/xen/xen_snd_front.c | 193 ++++++++-
>> sound/xen/xen_snd_front.h | 28 ++
>> sound/xen/xen_snd_front_alsa.c | 830 ++++++++++++++++++++++++++++++++++++++
>> sound/xen/xen_snd_front_alsa.h | 23 ++
>> sound/xen/xen_snd_front_evtchnl.c | 6 +-
>> 6 files changed, 1080 insertions(+), 3 deletions(-)
>> create mode 100644 sound/xen/xen_snd_front_alsa.c
>> create mode 100644 sound/xen/xen_snd_front_alsa.h
>>
>> diff --git a/sound/xen/Makefile b/sound/xen/Makefile
>> index f028bc30af5d..1e6470ecc2f2 100644
>> --- a/sound/xen/Makefile
>> +++ b/sound/xen/Makefile
>> @@ -3,6 +3,7 @@
>> snd_xen_front-objs := xen_snd_front.o \
>> xen_snd_front_cfg.o \
>> xen_snd_front_evtchnl.o \
>> - xen_snd_front_shbuf.o
>> + xen_snd_front_shbuf.o \
>> + xen_snd_front_alsa.o
>>
>> obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
>> diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
>> index 0569c6c596a3..1fef253ea21a 100644
>> --- a/sound/xen/xen_snd_front.c
>> +++ b/sound/xen/xen_snd_front.c
>> @@ -19,10 +19,201 @@
>> #include <xen/interface/io/sndif.h>
>>
>> #include "xen_snd_front.h"
>> +#include "xen_snd_front_alsa.h"
>> #include "xen_snd_front_evtchnl.h"
>> +#include "xen_snd_front_shbuf.h"
>> +
>> +static struct xensnd_req *
>> +be_stream_prepare_req(struct xen_snd_front_evtchnl *evtchnl, u8 operation)
>> +{
>> + struct xensnd_req *req;
>> +
>> + req = RING_GET_REQUEST(&evtchnl->u.req.ring,
>> + evtchnl->u.req.ring.req_prod_pvt);
>> + req->operation = operation;
>> + req->id = evtchnl->evt_next_id++;
>> + evtchnl->evt_id = req->id;
>> + return req;
>> +}
>> +
>> +static int be_stream_do_io(struct xen_snd_front_evtchnl *evtchnl)
>> +{
>> + if (unlikely(evtchnl->state != EVTCHNL_STATE_CONNECTED))
>> + return -EIO;
>> +
>> + reinit_completion(&evtchnl->u.req.completion);
>> + xen_snd_front_evtchnl_flush(evtchnl);
>> + return 0;
>> +}
>> +
>> +static int be_stream_wait_io(struct xen_snd_front_evtchnl *evtchnl)
>> +{
>> + if (wait_for_completion_timeout(&evtchnl->u.req.completion,
>> + msecs_to_jiffies(VSND_WAIT_BACK_MS)) <= 0)
>> + return -ETIMEDOUT;
>> +
>> + return evtchnl->u.req.resp_status;
>> +}
>> +
>> +int xen_snd_front_stream_query_hw_param(struct xen_snd_front_evtchnl *evtchnl,
>> + struct xensnd_query_hw_param *hw_param_req,
>> + struct xensnd_query_hw_param *hw_param_resp)
>> +{
>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>> + struct xensnd_req *req;
>> + unsigned long flags;
>> + int ret;
>> +
>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>> +
>> + spin_lock_irqsave(&front_info->io_lock, flags);
>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_HW_PARAM_QUERY);
>> + req->op.hw_param = *hw_param_req;
>> +
>> + ret = be_stream_do_io(evtchnl);
>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>> +
>> + if (ret == 0)
>> + ret = be_stream_wait_io(evtchnl);
>> +
>> + if (ret == 0)
>> + *hw_param_resp = evtchnl->u.req.resp.hw_param;
>> +
>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>> + return ret;
>> +}
>> +
>> +int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl *evtchnl,
>> + struct xen_snd_front_shbuf *sh_buf,
>> + u8 format, unsigned int channels,
>> + unsigned int rate, u32 buffer_sz,
>> + u32 period_sz)
>> +{
>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>> + struct xensnd_req *req;
>> + unsigned long flags;
>> + int ret;
>> +
>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>> +
>> + spin_lock_irqsave(&front_info->io_lock, flags);
>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_OPEN);
>> + req->op.open.pcm_format = format;
>> + req->op.open.pcm_channels = channels;
>> + req->op.open.pcm_rate = rate;
>> + req->op.open.buffer_sz = buffer_sz;
>> + req->op.open.period_sz = period_sz;
>> + req->op.open.gref_directory = xen_snd_front_shbuf_get_dir_start(sh_buf);
>> +
>> + ret = be_stream_do_io(evtchnl);
>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>> +
>> + if (ret == 0)
>> + ret = be_stream_wait_io(evtchnl);
>> +
>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>> + return ret;
>> +}
>> +
>> +int xen_snd_front_stream_close(struct xen_snd_front_evtchnl *evtchnl)
>> +{
>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>> + struct xensnd_req *req;
>> + unsigned long flags;
>> + int ret;
>> +
>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>> +
>> + spin_lock_irqsave(&front_info->io_lock, flags);
>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_CLOSE);
>> +
>> + ret = be_stream_do_io(evtchnl);
>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>> +
>> + if (ret == 0)
>> + ret = be_stream_wait_io(evtchnl);
>> +
>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>> + return ret;
>> +}
>> +
>> +int xen_snd_front_stream_write(struct xen_snd_front_evtchnl *evtchnl,
>> + unsigned long pos, unsigned long count)
>> +{
>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>> + struct xensnd_req *req;
>> + unsigned long flags;
>> + int ret;
>> +
>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>> +
>> + spin_lock_irqsave(&front_info->io_lock, flags);
>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_WRITE);
>> + req->op.rw.length = count;
>> + req->op.rw.offset = pos;
>> +
>> + ret = be_stream_do_io(evtchnl);
>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>> +
>> + if (ret == 0)
>> + ret = be_stream_wait_io(evtchnl);
>> +
>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>> + return ret;
>> +}
>> +
>> +int xen_snd_front_stream_read(struct xen_snd_front_evtchnl *evtchnl,
>> + unsigned long pos, unsigned long count)
>> +{
>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>> + struct xensnd_req *req;
>> + unsigned long flags;
>> + int ret;
>> +
>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>> +
>> + spin_lock_irqsave(&front_info->io_lock, flags);
>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_READ);
>> + req->op.rw.length = count;
>> + req->op.rw.offset = pos;
>> +
>> + ret = be_stream_do_io(evtchnl);
>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>> +
>> + if (ret == 0)
>> + ret = be_stream_wait_io(evtchnl);
>> +
>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>> + return ret;
>> +}
>> +
>> +int xen_snd_front_stream_trigger(struct xen_snd_front_evtchnl *evtchnl,
>> + int type)
>> +{
>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>> + struct xensnd_req *req;
>> + unsigned long flags;
>> + int ret;
>> +
>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>> +
>> + spin_lock_irqsave(&front_info->io_lock, flags);
>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_TRIGGER);
>> + req->op.trigger.type = type;
>> +
>> + ret = be_stream_do_io(evtchnl);
>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>> +
>> + if (ret == 0)
>> + ret = be_stream_wait_io(evtchnl);
>> +
>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>> + return ret;
>> +}
>>
>> static void xen_snd_drv_fini(struct xen_snd_front_info *front_info)
>> {
>> + xen_snd_front_alsa_fini(front_info);
>> xen_snd_front_evtchnl_free_all(front_info);
>> }
>>
>> @@ -45,7 +236,7 @@ static int sndback_initwait(struct xen_snd_front_info *front_info)
>>
>> static int sndback_connect(struct xen_snd_front_info *front_info)
>> {
>> - return 0;
>> + return xen_snd_front_alsa_init(front_info);
>> }
>>
>> static void sndback_disconnect(struct xen_snd_front_info *front_info)
>> diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
>> index 9c2ffbb4e4b8..7adbdb4d2019 100644
>> --- a/sound/xen/xen_snd_front.h
>> +++ b/sound/xen/xen_snd_front.h
>> @@ -13,17 +13,45 @@
>>
>> #include "xen_snd_front_cfg.h"
>>
>> +struct card_info;
>> +struct xen_snd_front_evtchnl;
>> struct xen_snd_front_evtchnl_pair;
>> +struct xen_snd_front_shbuf;
>> +struct xensnd_query_hw_param;
>>
>> struct xen_snd_front_info {
>> struct xenbus_device *xb_dev;
>>
>> + struct card_info *card_info;
>> +
>> /* serializer for backend IO: request/response */
>> spinlock_t io_lock;
>> +
>> int num_evt_pairs;
>> struct xen_snd_front_evtchnl_pair *evt_pairs;
>>
>> struct xen_front_cfg_card cfg;
>> };
>>
>> +int xen_snd_front_stream_query_hw_param(struct xen_snd_front_evtchnl *evtchnl,
>> + struct xensnd_query_hw_param *hw_param_req,
>> + struct xensnd_query_hw_param *hw_param_resp);
>> +
>> +int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl *evtchnl,
>> + struct xen_snd_front_shbuf *sh_buf,
>> + u8 format, unsigned int channels,
>> + unsigned int rate, u32 buffer_sz,
>> + u32 period_sz);
>> +
>> +int xen_snd_front_stream_close(struct xen_snd_front_evtchnl *evtchnl);
>> +
>> +int xen_snd_front_stream_write(struct xen_snd_front_evtchnl *evtchnl,
>> + unsigned long pos, unsigned long count);
>> +
>> +int xen_snd_front_stream_read(struct xen_snd_front_evtchnl *evtchnl,
>> + unsigned long pos, unsigned long count);
>> +
>> +int xen_snd_front_stream_trigger(struct xen_snd_front_evtchnl *evtchnl,
>> + int type);
>> +
>> #endif /* __XEN_SND_FRONT_H */
>> diff --git a/sound/xen/xen_snd_front_alsa.c b/sound/xen/xen_snd_front_alsa.c
>> new file mode 100644
>> index 000000000000..f524b172750e
>> --- /dev/null
>> +++ b/sound/xen/xen_snd_front_alsa.c
>> @@ -0,0 +1,830 @@
>> +// SPDX-License-Identifier: GPL-2.0 OR MIT
>> +
>> +/*
>> + * Xen para-virtual sound device
>> + *
>> + * Copyright (C) 2016-2018 EPAM Systems Inc.
>> + *
>> + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>> + */
>> +
>> +#include <linux/platform_device.h>
>> +
>> +#include <sound/core.h>
>> +#include <sound/pcm.h>
>> +#include <sound/pcm_params.h>
>> +
>> +#include <xen/xenbus.h>
>> +
>> +#include "xen_snd_front.h"
>> +#include "xen_snd_front_alsa.h"
>> +#include "xen_snd_front_cfg.h"
>> +#include "xen_snd_front_evtchnl.h"
>> +#include "xen_snd_front_shbuf.h"
>> +
>> +struct pcm_stream_info {
> Not sure how this is generally handled in the sound drivers, but when
> reviewing the code using those structures I repeatedly tried to find
> their definitions in the sound headers instead of here. Same applies to
> the alsa_* names.
>
> I'd prefer names which don't poison the name space.
I'll try to do something about naming
>> + struct xen_snd_front_info *front_info;
>> + struct xen_snd_front_evtchnl_pair *evt_pair;
>> + struct xen_snd_front_shbuf sh_buf;
>> + int index;
>> +
>> + bool is_open;
>> + struct snd_pcm_hardware pcm_hw;
>> +
>> + /* number of processed frames as reported by the backend */
>> + snd_pcm_uframes_t be_cur_frame;
>> + /* current HW pointer to be reported via .period callback */
>> + atomic_t hw_ptr;
>> + /* modulo of the number of processed frames - for period detection */
>> + u32 out_frames;
>> +};
>> +
>> +struct pcm_instance_info {
>> + struct card_info *card_info;
>> + struct snd_pcm *pcm;
>> + struct snd_pcm_hardware pcm_hw;
>> + int num_pcm_streams_pb;
>> + struct pcm_stream_info *streams_pb;
>> + int num_pcm_streams_cap;
>> + struct pcm_stream_info *streams_cap;
>> +};
>> +
>> +struct card_info {
>> + struct xen_snd_front_info *front_info;
>> + struct snd_card *card;
>> + struct snd_pcm_hardware pcm_hw;
>> + int num_pcm_instances;
>> + struct pcm_instance_info *pcm_instances;
>> +};
>> +
>> +struct alsa_sndif_sample_format {
>> + u8 sndif;
>> + snd_pcm_format_t alsa;
>> +};
>> +
>> +struct alsa_sndif_hw_param {
>> + u8 sndif;
>> + snd_pcm_hw_param_t alsa;
>> +};
>> +
>> +static const struct alsa_sndif_sample_format ALSA_SNDIF_FORMATS[] = {
>> + {
>> + .sndif = XENSND_PCM_FORMAT_U8,
>> + .alsa = SNDRV_PCM_FORMAT_U8
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_S8,
>> + .alsa = SNDRV_PCM_FORMAT_S8
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_U16_LE,
>> + .alsa = SNDRV_PCM_FORMAT_U16_LE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_U16_BE,
>> + .alsa = SNDRV_PCM_FORMAT_U16_BE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_S16_LE,
>> + .alsa = SNDRV_PCM_FORMAT_S16_LE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_S16_BE,
>> + .alsa = SNDRV_PCM_FORMAT_S16_BE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_U24_LE,
>> + .alsa = SNDRV_PCM_FORMAT_U24_LE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_U24_BE,
>> + .alsa = SNDRV_PCM_FORMAT_U24_BE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_S24_LE,
>> + .alsa = SNDRV_PCM_FORMAT_S24_LE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_S24_BE,
>> + .alsa = SNDRV_PCM_FORMAT_S24_BE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_U32_LE,
>> + .alsa = SNDRV_PCM_FORMAT_U32_LE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_U32_BE,
>> + .alsa = SNDRV_PCM_FORMAT_U32_BE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_S32_LE,
>> + .alsa = SNDRV_PCM_FORMAT_S32_LE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_S32_BE,
>> + .alsa = SNDRV_PCM_FORMAT_S32_BE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_A_LAW,
>> + .alsa = SNDRV_PCM_FORMAT_A_LAW
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_MU_LAW,
>> + .alsa = SNDRV_PCM_FORMAT_MU_LAW
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_F32_LE,
>> + .alsa = SNDRV_PCM_FORMAT_FLOAT_LE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_F32_BE,
>> + .alsa = SNDRV_PCM_FORMAT_FLOAT_BE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_F64_LE,
>> + .alsa = SNDRV_PCM_FORMAT_FLOAT64_LE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_F64_BE,
>> + .alsa = SNDRV_PCM_FORMAT_FLOAT64_BE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE,
>> + .alsa = SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE,
>> + .alsa = SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_IMA_ADPCM,
>> + .alsa = SNDRV_PCM_FORMAT_IMA_ADPCM
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_MPEG,
>> + .alsa = SNDRV_PCM_FORMAT_MPEG
>> + },
>> + {
>> + .sndif = XENSND_PCM_FORMAT_GSM,
>> + .alsa = SNDRV_PCM_FORMAT_GSM
>> + },
>> +};
>> +
>> +static int to_sndif_format(snd_pcm_format_t format)
>> +{
>> + int i;
>> +
>> + for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
>> + if (ALSA_SNDIF_FORMATS[i].alsa == format)
>> + return ALSA_SNDIF_FORMATS[i].sndif;
>> +
>> + return -EINVAL;
>> +}
>> +
>> +static u64 to_sndif_formats_mask(u64 alsa_formats)
>> +{
>> + u64 mask;
>> + int i;
>> +
>> + mask = 0;
>> + for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
>> + if (1 << ALSA_SNDIF_FORMATS[i].alsa & alsa_formats)
>> + mask |= 1 << ALSA_SNDIF_FORMATS[i].sndif;
>> +
>> + return mask;
>> +}
>> +
>> +static u64 to_alsa_formats_mask(u64 sndif_formats)
>> +{
>> + u64 mask;
>> + int i;
>> +
>> + mask = 0;
>> + for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
>> + if (1 << ALSA_SNDIF_FORMATS[i].sndif & sndif_formats)
>> + mask |= 1 << ALSA_SNDIF_FORMATS[i].alsa;
>> +
>> + return mask;
>> +}
>> +
>> +static void stream_clear(struct pcm_stream_info *stream)
>> +{
>> + stream->is_open = false;
>> + stream->be_cur_frame = 0;
>> + stream->out_frames = 0;
>> + atomic_set(&stream->hw_ptr, 0);
>> + xen_snd_front_evtchnl_pair_clear(stream->evt_pair);
>> + xen_snd_front_shbuf_clear(&stream->sh_buf);
>> +}
>> +
>> +static void stream_free(struct pcm_stream_info *stream)
>> +{
>> + xen_snd_front_shbuf_free(&stream->sh_buf);
>> + stream_clear(stream);
>> +}
>> +
>> +static struct pcm_stream_info *stream_get(struct snd_pcm_substream *substream)
>> +{
>> + struct pcm_instance_info *pcm_instance =
>> + snd_pcm_substream_chip(substream);
>> + struct pcm_stream_info *stream;
>> +
>> + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
>> + stream = &pcm_instance->streams_pb[substream->number];
>> + else
>> + stream = &pcm_instance->streams_cap[substream->number];
>> +
>> + return stream;
>> +}
>> +
>> +static int alsa_hw_rule(struct snd_pcm_hw_params *params,
>> + struct snd_pcm_hw_rule *rule)
>> +{
>> + struct pcm_stream_info *stream = rule->private;
>> + struct device *dev = &stream->front_info->xb_dev->dev;
>> + struct snd_mask *formats =
>> + hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
>> + struct snd_interval *rates =
>> + hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
>> + struct snd_interval *channels =
>> + hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
>> + struct snd_interval *period =
>> + hw_param_interval(params,
>> + SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
>> + struct snd_interval *buffer =
>> + hw_param_interval(params,
>> + SNDRV_PCM_HW_PARAM_BUFFER_SIZE);
>> + struct xensnd_query_hw_param req;
>> + struct xensnd_query_hw_param resp;
>> + struct snd_interval interval;
>> + struct snd_mask mask;
>> + u64 sndif_formats;
>> + int changed, ret;
>> +
>> + /* collect all the values we need for the query */
>> +
>> + req.formats = to_sndif_formats_mask((u64)formats->bits[0] |
>> + (u64)(formats->bits[1]) << 32);
>> +
>> + req.rates.min = rates->min;
>> + req.rates.max = rates->max;
>> +
>> + req.channels.min = channels->min;
>> + req.channels.max = channels->max;
>> +
>> + req.buffer.min = buffer->min;
>> + req.buffer.max = buffer->max;
>> +
>> + req.period.min = period->min;
>> + req.period.max = period->max;
>> +
>> + ret = xen_snd_front_stream_query_hw_param(&stream->evt_pair->req,
>> + &req, &resp);
>> + if (ret < 0) {
>> + /* check if this is due to backend communication error */
>> + if (ret == -EIO || ret == -ETIMEDOUT)
>> + dev_err(dev, "Failed to query ALSA HW parameters\n");
>> + return ret;
>> + }
>> +
>> + /* refine HW parameters after the query */
>> + changed = 0;
>> +
>> + sndif_formats = to_alsa_formats_mask(resp.formats);
>> + snd_mask_none(&mask);
>> + mask.bits[0] = (u32)sndif_formats;
>> + mask.bits[1] = (u32)(sndif_formats >> 32);
>> + ret = snd_mask_refine(formats, &mask);
>> + if (ret < 0)
>> + return ret;
>> + changed |= ret;
>> +
>> + interval.openmin = 0;
>> + interval.openmax = 0;
>> + interval.integer = 1;
>> +
>> + interval.min = resp.rates.min;
>> + interval.max = resp.rates.max;
>> + ret = snd_interval_refine(rates, &interval);
>> + if (ret < 0)
>> + return ret;
>> + changed |= ret;
>> +
>> + interval.min = resp.channels.min;
>> + interval.max = resp.channels.max;
>> + ret = snd_interval_refine(channels, &interval);
>> + if (ret < 0)
>> + return ret;
>> + changed |= ret;
>> +
>> + interval.min = resp.buffer.min;
>> + interval.max = resp.buffer.max;
>> + ret = snd_interval_refine(buffer, &interval);
>> + if (ret < 0)
>> + return ret;
>> + changed |= ret;
>> +
>> + interval.min = resp.period.min;
>> + interval.max = resp.period.max;
>> + ret = snd_interval_refine(period, &interval);
>> + if (ret < 0)
>> + return ret;
>> + changed |= ret;
>> +
>> + return changed;
>> +}
>> +
>> +static int alsa_open(struct snd_pcm_substream *substream)
>> +{
>> + struct pcm_instance_info *pcm_instance =
>> + snd_pcm_substream_chip(substream);
>> + struct pcm_stream_info *stream = stream_get(substream);
>> + struct snd_pcm_runtime *runtime = substream->runtime;
>> + struct xen_snd_front_info *front_info =
>> + pcm_instance->card_info->front_info;
>> + struct device *dev = &front_info->xb_dev->dev;
>> + unsigned long flags;
>> + int ret;
>> +
>> + /*
>> + * return our HW properties: override defaults with those configured
>> + * via XenStore
>> + */
>> + runtime->hw = stream->pcm_hw;
>> + runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |
>> + SNDRV_PCM_INFO_MMAP_VALID |
>> + SNDRV_PCM_INFO_DOUBLE |
>> + SNDRV_PCM_INFO_BATCH |
>> + SNDRV_PCM_INFO_NONINTERLEAVED |
>> + SNDRV_PCM_INFO_RESUME |
>> + SNDRV_PCM_INFO_PAUSE);
>> + runtime->hw.info |= SNDRV_PCM_INFO_INTERLEAVED;
>> +
>> + spin_lock_irqsave(&front_info->io_lock, flags);
>> +
>> + stream->evt_pair = &front_info->evt_pairs[stream->index];
>> +
>> + stream->front_info = front_info;
>> +
>> + xen_snd_front_evtchnl_pair_set_connected(stream->evt_pair, true);
>> +
>> + stream->evt_pair->evt.u.evt.substream = substream;
>> +
>> + stream_clear(stream);
>> +
>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>> +
>> + ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
>> + alsa_hw_rule, stream,
>> + SNDRV_PCM_HW_PARAM_FORMAT, -1);
>> + if (ret) {
>> + dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_FORMAT\n");
>> + return ret;
>> + }
>> +
>> + ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
>> + alsa_hw_rule, stream,
>> + SNDRV_PCM_HW_PARAM_RATE, -1);
>> + if (ret) {
>> + dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_RATE\n");
>> + return ret;
>> + }
>> +
>> + ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
>> + alsa_hw_rule, stream,
>> + SNDRV_PCM_HW_PARAM_CHANNELS, -1);
>> + if (ret) {
>> + dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_CHANNELS\n");
>> + return ret;
>> + }
>> +
>> + ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
>> + alsa_hw_rule, stream,
>> + SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
>> + if (ret) {
>> + dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_PERIOD_SIZE\n");
>> + return ret;
>> + }
>> +
>> + ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
>> + alsa_hw_rule, stream,
>> + SNDRV_PCM_HW_PARAM_BUFFER_SIZE, -1);
>> + if (ret) {
>> + dev_err(dev, "Failed to add HW rule for SNDRV_PCM_HW_PARAM_BUFFER_SIZE\n");
>> + return ret;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int alsa_close(struct snd_pcm_substream *substream)
>> +{
>> + struct pcm_stream_info *stream = stream_get(substream);
>> + unsigned long flags;
>> +
>> + spin_lock_irqsave(&stream->front_info->io_lock, flags);
>> +
>> + xen_snd_front_evtchnl_pair_set_connected(stream->evt_pair, false);
>> +
>> + spin_unlock_irqrestore(&stream->front_info->io_lock, flags);
>> + return 0;
>> +}
>> +
>> +static int alsa_hw_params(struct snd_pcm_substream *substream,
>> + struct snd_pcm_hw_params *params)
>> +{
>> + struct pcm_stream_info *stream = stream_get(substream);
>> + int ret;
>> +
>> + /*
>> + * this callback may be called multiple times,
>> + * so free the previously allocated shared buffer if any
>> + */
>> + stream_free(stream);
>> +
>> + ret = xen_snd_front_shbuf_alloc(stream->front_info->xb_dev,
>> + &stream->sh_buf,
>> + params_buffer_bytes(params));
>> + if (ret < 0) {
>> + stream_free(stream);
>> + dev_err(&stream->front_info->xb_dev->dev,
>> + "Failed to allocate buffers for stream with index %d\n",
>> + stream->index);
>> + return ret;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int alsa_hw_free(struct snd_pcm_substream *substream)
>> +{
>> + struct pcm_stream_info *stream = stream_get(substream);
>> + int ret;
>> +
>> + ret = xen_snd_front_stream_close(&stream->evt_pair->req);
>> + stream_free(stream);
>> + return ret;
>> +}
>> +
>> +static int alsa_prepare(struct snd_pcm_substream *substream)
>> +{
>> + struct pcm_stream_info *stream = stream_get(substream);
>> +
>> + if (!stream->is_open) {
>> + struct snd_pcm_runtime *runtime = substream->runtime;
>> + u8 sndif_format;
>> + int ret;
>> +
>> + sndif_format = to_sndif_format(runtime->format);
>> + if (sndif_format < 0) {
>> + dev_err(&stream->front_info->xb_dev->dev,
>> + "Unsupported sample format: %d\n",
>> + runtime->format);
>> + return sndif_format;
>> + }
>> +
>> + ret = xen_snd_front_stream_prepare(&stream->evt_pair->req,
>> + &stream->sh_buf,
>> + sndif_format,
>> + runtime->channels,
>> + runtime->rate,
>> + snd_pcm_lib_buffer_bytes(substream),
>> + snd_pcm_lib_period_bytes(substream));
>> + if (ret < 0)
>> + return ret;
>> +
>> + stream->is_open = true;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int alsa_trigger(struct snd_pcm_substream *substream, int cmd)
>> +{
>> + struct pcm_stream_info *stream = stream_get(substream);
>> + int type;
>> +
>> + switch (cmd) {
>> + case SNDRV_PCM_TRIGGER_START:
>> + type = XENSND_OP_TRIGGER_START;
>> + break;
>> +
>> + case SNDRV_PCM_TRIGGER_RESUME:
>> + type = XENSND_OP_TRIGGER_RESUME;
>> + break;
>> +
>> + case SNDRV_PCM_TRIGGER_STOP:
>> + type = XENSND_OP_TRIGGER_STOP;
>> + break;
>> +
>> + case SNDRV_PCM_TRIGGER_SUSPEND:
>> + type = XENSND_OP_TRIGGER_PAUSE;
>> + break;
>> +
>> + default:
>> + return -EINVAL;
>> + }
>> +
>> + return xen_snd_front_stream_trigger(&stream->evt_pair->req, type);
>> +}
>> +
>> +void xen_snd_front_alsa_handle_cur_pos(struct xen_snd_front_evtchnl *evtchnl,
>> + u64 pos_bytes)
>> +{
>> + struct snd_pcm_substream *substream = evtchnl->u.evt.substream;
>> + struct pcm_stream_info *stream = stream_get(substream);
>> + snd_pcm_uframes_t delta, new_hw_ptr, cur_frame;
>> +
>> + cur_frame = bytes_to_frames(substream->runtime, pos_bytes);
>> +
>> + delta = cur_frame - stream->be_cur_frame;
>> + stream->be_cur_frame = cur_frame;
>> +
>> + new_hw_ptr = (snd_pcm_uframes_t)atomic_read(&stream->hw_ptr);
>> + new_hw_ptr = (new_hw_ptr + delta) % substream->runtime->buffer_size;
>> + atomic_set(&stream->hw_ptr, (int)new_hw_ptr);
>> +
>> + stream->out_frames += delta;
>> + if (stream->out_frames > substream->runtime->period_size) {
>> + stream->out_frames %= substream->runtime->period_size;
>> + snd_pcm_period_elapsed(substream);
>> + }
>> +}
>> +
>> +static snd_pcm_uframes_t alsa_pointer(struct snd_pcm_substream *substream)
>> +{
>> + struct pcm_stream_info *stream = stream_get(substream);
>> +
>> + return (snd_pcm_uframes_t)atomic_read(&stream->hw_ptr);
>> +}
>> +
>> +static int alsa_pb_copy_user(struct snd_pcm_substream *substream,
>> + int channel, unsigned long pos, void __user *src,
>> + unsigned long count)
>> +{
>> + struct pcm_stream_info *stream = stream_get(substream);
>> +
>> + if (unlikely(pos + count > stream->sh_buf.buffer_sz))
>> + return -EINVAL;
>> +
>> + if (copy_from_user(stream->sh_buf.buffer + pos, src, count))
>> + return -EFAULT;
>> +
>> + return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
>> +}
>> +
>> +static int alsa_pb_copy_kernel(struct snd_pcm_substream *substream,
>> + int channel, unsigned long pos, void *src,
>> + unsigned long count)
>> +{
>> + struct pcm_stream_info *stream = stream_get(substream);
>> +
>> + if (unlikely(pos + count > stream->sh_buf.buffer_sz))
>> + return -EINVAL;
>> +
>> + memcpy(stream->sh_buf.buffer + pos, src, count);
>> +
>> + return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
>> +}
>> +
>> +static int alsa_cap_copy_user(struct snd_pcm_substream *substream,
>> + int channel, unsigned long pos, void __user *dst,
>> + unsigned long count)
>> +{
>> + struct pcm_stream_info *stream = stream_get(substream);
>> + int ret;
>> +
>> + if (unlikely(pos + count > stream->sh_buf.buffer_sz))
>> + return -EINVAL;
>> +
>> + ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos, count);
>> + if (ret < 0)
>> + return ret;
>> +
>> + return copy_to_user(dst, stream->sh_buf.buffer + pos, count) ?
>> + -EFAULT : 0;
>> +}
>> +
>> +static int alsa_cap_copy_kernel(struct snd_pcm_substream *substream,
>> + int channel, unsigned long pos, void *dst,
>> + unsigned long count)
>> +{
>> + struct pcm_stream_info *stream = stream_get(substream);
>> + int ret;
>> +
>> + if (unlikely(pos + count > stream->sh_buf.buffer_sz))
>> + return -EINVAL;
>> +
>> + ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos, count);
>> + if (ret < 0)
>> + return ret;
>> +
>> + memcpy(dst, stream->sh_buf.buffer + pos, count);
>> +
>> + return 0;
>> +}
>> +
>> +static int alsa_pb_fill_silence(struct snd_pcm_substream *substream,
>> + int channel, unsigned long pos,
>> + unsigned long count)
>> +{
>> + struct pcm_stream_info *stream = stream_get(substream);
>> +
>> + if (unlikely(pos + count > stream->sh_buf.buffer_sz))
>> + return -EINVAL;
>> +
>> + memset(stream->sh_buf.buffer + pos, 0, count);
>> +
>> + return xen_snd_front_stream_write(&stream->evt_pair->req, pos, count);
>> +}
>> +
>> +/*
>> + * FIXME: The mmaped data transfer is asynchronous and there is no
>> + * ack signal from user-space when it is done. This is the
>> + * reason it is not implemented in the PV driver as we do need
>> + * to know when the buffer can be transferred to the backend.
>> + */
>> +
>> +static struct snd_pcm_ops snd_drv_alsa_playback_ops = {
>> + .open = alsa_open,
>> + .close = alsa_close,
>> + .ioctl = snd_pcm_lib_ioctl,
>> + .hw_params = alsa_hw_params,
>> + .hw_free = alsa_hw_free,
>> + .prepare = alsa_prepare,
>> + .trigger = alsa_trigger,
>> + .pointer = alsa_pointer,
>> + .copy_user = alsa_pb_copy_user,
>> + .copy_kernel = alsa_pb_copy_kernel,
>> + .fill_silence = alsa_pb_fill_silence,
>> +};
>> +
>> +static struct snd_pcm_ops snd_drv_alsa_capture_ops = {
>> + .open = alsa_open,
>> + .close = alsa_close,
>> + .ioctl = snd_pcm_lib_ioctl,
>> + .hw_params = alsa_hw_params,
>> + .hw_free = alsa_hw_free,
>> + .prepare = alsa_prepare,
>> + .trigger = alsa_trigger,
>> + .pointer = alsa_pointer,
>> + .copy_user = alsa_cap_copy_user,
>> + .copy_kernel = alsa_cap_copy_kernel,
>> +};
>> +
>> +static int new_pcm_instance(struct card_info *card_info,
>> + struct xen_front_cfg_pcm_instance *instance_cfg,
>> + struct pcm_instance_info *pcm_instance_info)
>> +{
>> + struct snd_pcm *pcm;
>> + int ret, i;
>> +
>> + dev_dbg(&card_info->front_info->xb_dev->dev,
>> + "New PCM device \"%s\" with id %d playback %d capture %d",
>> + instance_cfg->name,
>> + instance_cfg->device_id,
>> + instance_cfg->num_streams_pb,
>> + instance_cfg->num_streams_cap);
>> +
>> + pcm_instance_info->card_info = card_info;
>> +
>> + pcm_instance_info->pcm_hw = instance_cfg->pcm_hw;
>> +
>> + if (instance_cfg->num_streams_pb) {
>> + pcm_instance_info->streams_pb =
>> + devm_kcalloc(&card_info->card->card_dev,
>> + instance_cfg->num_streams_pb,
>> + sizeof(struct pcm_stream_info),
>> + GFP_KERNEL);
>> + if (!pcm_instance_info->streams_pb)
>> + return -ENOMEM;
>> + }
>> +
>> + if (instance_cfg->num_streams_cap) {
>> + pcm_instance_info->streams_cap =
>> + devm_kcalloc(&card_info->card->card_dev,
>> + instance_cfg->num_streams_cap,
>> + sizeof(struct pcm_stream_info),
>> + GFP_KERNEL);
>> + if (!pcm_instance_info->streams_cap)
>> + return -ENOMEM;
>> + }
>> +
>> + pcm_instance_info->num_pcm_streams_pb =
>> + instance_cfg->num_streams_pb;
>> + pcm_instance_info->num_pcm_streams_cap =
>> + instance_cfg->num_streams_cap;
>> +
>> + for (i = 0; i < pcm_instance_info->num_pcm_streams_pb; i++) {
>> + pcm_instance_info->streams_pb[i].pcm_hw =
>> + instance_cfg->streams_pb[i].pcm_hw;
>> + pcm_instance_info->streams_pb[i].index =
>> + instance_cfg->streams_pb[i].index;
>> + }
>> +
>> + for (i = 0; i < pcm_instance_info->num_pcm_streams_cap; i++) {
>> + pcm_instance_info->streams_cap[i].pcm_hw =
>> + instance_cfg->streams_cap[i].pcm_hw;
>> + pcm_instance_info->streams_cap[i].index =
>> + instance_cfg->streams_cap[i].index;
>> + }
>> +
>> + ret = snd_pcm_new(card_info->card, instance_cfg->name,
>> + instance_cfg->device_id,
>> + instance_cfg->num_streams_pb,
>> + instance_cfg->num_streams_cap,
>> + &pcm);
>> + if (ret < 0)
>> + return ret;
>> +
>> + pcm->private_data = pcm_instance_info;
>> + pcm->info_flags = 0;
>> + /* we want to handle all PCM operations in non-atomic context */
>> + pcm->nonatomic = true;
>> + strncpy(pcm->name, "Virtual card PCM", sizeof(pcm->name));
>> +
>> + if (instance_cfg->num_streams_pb)
>> + snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
>> + &snd_drv_alsa_playback_ops);
>> +
>> + if (instance_cfg->num_streams_cap)
>> + snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,
>> + &snd_drv_alsa_capture_ops);
>> +
>> + pcm_instance_info->pcm = pcm;
>> + return 0;
>> +}
>> +
>> +int xen_snd_front_alsa_init(struct xen_snd_front_info *front_info)
>> +{
>> + struct device *dev = &front_info->xb_dev->dev;
>> + struct xen_front_cfg_card *cfg = &front_info->cfg;
>> + struct card_info *card_info;
>> + struct snd_card *card;
>> + int ret, i;
>> +
>> + dev_dbg(dev, "Creating virtual sound card\n");
>> +
>> + ret = snd_card_new(dev, 0, XENSND_DRIVER_NAME, THIS_MODULE,
>> + sizeof(struct card_info), &card);
>> + if (ret < 0)
>> + return ret;
>> +
>> + card_info = card->private_data;
>> + card_info->front_info = front_info;
>> + front_info->card_info = card_info;
>> + card_info->card = card;
>> + card_info->pcm_instances =
>> + devm_kcalloc(dev, cfg->num_pcm_instances,
>> + sizeof(struct pcm_instance_info),
>> + GFP_KERNEL);
>> + if (!card_info->pcm_instances) {
>> + ret = -ENOMEM;
>> + goto fail;
>> + }
>> +
>> + card_info->num_pcm_instances = cfg->num_pcm_instances;
>> + card_info->pcm_hw = cfg->pcm_hw;
>> +
>> + for (i = 0; i < cfg->num_pcm_instances; i++) {
>> + ret = new_pcm_instance(card_info, &cfg->pcm_instances[i],
>> + &card_info->pcm_instances[i]);
>> + if (ret < 0)
>> + goto fail;
>> + }
>> +
>> + strncpy(card->driver, XENSND_DRIVER_NAME, sizeof(card->driver));
>> + strncpy(card->shortname, cfg->name_short, sizeof(card->shortname));
>> + strncpy(card->longname, cfg->name_long, sizeof(card->longname));
>> +
>> + ret = snd_card_register(card);
>> + if (ret < 0)
>> + goto fail;
>> +
>> + return 0;
>> +
>> +fail:
>> + snd_card_free(card);
>> + return ret;
>> +}
>> +
>> +void xen_snd_front_alsa_fini(struct xen_snd_front_info *front_info)
>> +{
>> + struct card_info *card_info;
>> + struct snd_card *card;
>> +
>> + card_info = front_info->card_info;
>> + if (!card_info)
>> + return;
>> +
>> + card = card_info->card;
>> + if (!card)
>> + return;
>> +
>> + dev_dbg(&front_info->xb_dev->dev, "Removing virtual sound card %d\n",
>> + card->number);
>> + snd_card_free(card);
>> +
>> + /* card_info will be freed when destroying front_info->xb_dev->dev */
>> + card_info->card = NULL;
>> +}
>> diff --git a/sound/xen/xen_snd_front_alsa.h b/sound/xen/xen_snd_front_alsa.h
>> new file mode 100644
>> index 000000000000..18abd9eec967
>> --- /dev/null
>> +++ b/sound/xen/xen_snd_front_alsa.h
>> @@ -0,0 +1,23 @@
>> +/* SPDX-License-Identifier: GPL-2.0 OR MIT */
>> +
>> +/*
>> + * Xen para-virtual sound device
>> + *
>> + * Copyright (C) 2016-2018 EPAM Systems Inc.
>> + *
>> + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>> + */
>> +
>> +#ifndef __XEN_SND_FRONT_ALSA_H
>> +#define __XEN_SND_FRONT_ALSA_H
>> +
>> +struct xen_snd_front_info;
>> +
>> +int xen_snd_front_alsa_init(struct xen_snd_front_info *front_info);
>> +
>> +void xen_snd_front_alsa_fini(struct xen_snd_front_info *front_info);
>> +
>> +void xen_snd_front_alsa_handle_cur_pos(struct xen_snd_front_evtchnl *evtchnl,
>> + u64 pos_bytes);
>> +
>> +#endif /* __XEN_SND_FRONT_ALSA_H */
>> diff --git a/sound/xen/xen_snd_front_evtchnl.c b/sound/xen/xen_snd_front_evtchnl.c
>> index 9ece39f938f8..470196518716 100644
>> --- a/sound/xen/xen_snd_front_evtchnl.c
>> +++ b/sound/xen/xen_snd_front_evtchnl.c
>> @@ -14,6 +14,7 @@
>> #include <xen/xenbus.h>
>>
>> #include "xen_snd_front.h"
>> +#include "xen_snd_front_alsa.h"
>> #include "xen_snd_front_cfg.h"
>> #include "xen_snd_front_evtchnl.h"
>>
>> @@ -111,7 +112,10 @@ static irqreturn_t evtchnl_interrupt_evt(int irq, void *dev_id)
>>
>> switch (event->type) {
>> case XENSND_EVT_CUR_POS:
>> - /* do nothing at the moment */
>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>> + xen_snd_front_alsa_handle_cur_pos(channel,
>> + event->op.cur_pos.position);
>> + spin_lock_irqsave(&front_info->io_lock, flags);
> Is this correct? Why can you free the lock here without doing any
> harm? What is the lock protecting? I'd like to see at least some
> comments explaining why the lock is needed and why it can be dropped
> here.
Well, this code has issues and will be re-worked:
1. Which locks I need:
1.1. lock to serialize requests to backend
1.2. lock to protect the ring: between requests code and interrupt handler
2. I don't really need a spinlock here b/c interrupts are threaded,
so I can safely use a mutex: thus no need for fancy code with unlocking
and locking again while servicing xen_snd_front_alsa_handle_cur_pos
Thank you
>
> Juergen
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 5/5] ALSA: xen-front: Implement ALSA virtual sound driver
2018-04-17 11:32 ` Oleksandr Andrushchenko
@ 2018-04-17 12:26 ` Oleksandr Andrushchenko
2018-04-17 12:32 ` Juergen Gross
0 siblings, 1 reply; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-17 12:26 UTC (permalink / raw)
To: Juergen Gross, xen-devel, linux-kernel, alsa-devel,
boris.ostrovsky, konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 04/17/2018 02:32 PM, Oleksandr Andrushchenko wrote:
> On 04/16/2018 05:09 PM, Juergen Gross wrote:
>> On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
>>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>>
>>> Implement essential initialization of the sound driver:
>>> - introduce required data structures
>>> - handle driver registration
>>> - handle sound card registration
>>> - register sound driver on backend connection
>>> - remove sound driver on backend disconnect
>>>
>>> Initialize virtual sound card with streams according to the
>>> Xen store configuration.
>>>
>>> Implement ALSA driver operations including:
>>> - manage frontend/backend shared buffers
>>> - manage Xen bus event channel states
>>>
>>> Implement requests from front to back for ALSA
>>> PCM operations.
>>> - report ALSA period elapsed event: handle XENSND_EVT_CUR_POS
>>> notifications from the backend when stream position advances
>>> during playback/capture. The event carries a value of how
>>> many octets were played/captured at the time of the event.
>>> - implement explicit stream parameter negotiation between
>>> backend and frontend: handle XENSND_OP_HW_PARAM_QUERY request
>>> to read/update configuration space for the parameter given:
>>> request passes desired parameter interval and the response to
>>> this request returns min/max interval for the parameter to be used.
>>>
>>> Signed-off-by: Oleksandr Andrushchenko
>>> <oleksandr_andrushchenko@epam.com>
>>> ---
>>> sound/xen/Makefile | 3 +-
>>> sound/xen/xen_snd_front.c | 193 ++++++++-
>>> sound/xen/xen_snd_front.h | 28 ++
>>> sound/xen/xen_snd_front_alsa.c | 830
>>> ++++++++++++++++++++++++++++++++++++++
>>> sound/xen/xen_snd_front_alsa.h | 23 ++
>>> sound/xen/xen_snd_front_evtchnl.c | 6 +-
>>> 6 files changed, 1080 insertions(+), 3 deletions(-)
>>> create mode 100644 sound/xen/xen_snd_front_alsa.c
>>> create mode 100644 sound/xen/xen_snd_front_alsa.h
>>>
>>> diff --git a/sound/xen/Makefile b/sound/xen/Makefile
>>> index f028bc30af5d..1e6470ecc2f2 100644
>>> --- a/sound/xen/Makefile
>>> +++ b/sound/xen/Makefile
>>> @@ -3,6 +3,7 @@
>>> snd_xen_front-objs := xen_snd_front.o \
>>> xen_snd_front_cfg.o \
>>> xen_snd_front_evtchnl.o \
>>> - xen_snd_front_shbuf.o
>>> + xen_snd_front_shbuf.o \
>>> + xen_snd_front_alsa.o
>>> obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
>>> diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
>>> index 0569c6c596a3..1fef253ea21a 100644
>>> --- a/sound/xen/xen_snd_front.c
>>> +++ b/sound/xen/xen_snd_front.c
>>> @@ -19,10 +19,201 @@
>>> #include <xen/interface/io/sndif.h>
>>> #include "xen_snd_front.h"
>>> +#include "xen_snd_front_alsa.h"
>>> #include "xen_snd_front_evtchnl.h"
>>> +#include "xen_snd_front_shbuf.h"
>>> +
>>> +static struct xensnd_req *
>>> +be_stream_prepare_req(struct xen_snd_front_evtchnl *evtchnl, u8
>>> operation)
>>> +{
>>> + struct xensnd_req *req;
>>> +
>>> + req = RING_GET_REQUEST(&evtchnl->u.req.ring,
>>> + evtchnl->u.req.ring.req_prod_pvt);
>>> + req->operation = operation;
>>> + req->id = evtchnl->evt_next_id++;
>>> + evtchnl->evt_id = req->id;
>>> + return req;
>>> +}
>>> +
>>> +static int be_stream_do_io(struct xen_snd_front_evtchnl *evtchnl)
>>> +{
>>> + if (unlikely(evtchnl->state != EVTCHNL_STATE_CONNECTED))
>>> + return -EIO;
>>> +
>>> + reinit_completion(&evtchnl->u.req.completion);
>>> + xen_snd_front_evtchnl_flush(evtchnl);
>>> + return 0;
>>> +}
>>> +
>>> +static int be_stream_wait_io(struct xen_snd_front_evtchnl *evtchnl)
>>> +{
>>> + if (wait_for_completion_timeout(&evtchnl->u.req.completion,
>>> + msecs_to_jiffies(VSND_WAIT_BACK_MS)) <= 0)
>>> + return -ETIMEDOUT;
>>> +
>>> + return evtchnl->u.req.resp_status;
>>> +}
>>> +
>>> +int xen_snd_front_stream_query_hw_param(struct
>>> xen_snd_front_evtchnl *evtchnl,
>>> + struct xensnd_query_hw_param *hw_param_req,
>>> + struct xensnd_query_hw_param *hw_param_resp)
>>> +{
>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>> + struct xensnd_req *req;
>>> + unsigned long flags;
>>> + int ret;
>>> +
>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>> +
>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_HW_PARAM_QUERY);
>>> + req->op.hw_param = *hw_param_req;
>>> +
>>> + ret = be_stream_do_io(evtchnl);
>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>> +
>>> + if (ret == 0)
>>> + ret = be_stream_wait_io(evtchnl);
>>> +
>>> + if (ret == 0)
>>> + *hw_param_resp = evtchnl->u.req.resp.hw_param;
>>> +
>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>> + return ret;
>>> +}
>>> +
>>> +int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl
>>> *evtchnl,
>>> + struct xen_snd_front_shbuf *sh_buf,
>>> + u8 format, unsigned int channels,
>>> + unsigned int rate, u32 buffer_sz,
>>> + u32 period_sz)
>>> +{
>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>> + struct xensnd_req *req;
>>> + unsigned long flags;
>>> + int ret;
>>> +
>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>> +
>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_OPEN);
>>> + req->op.open.pcm_format = format;
>>> + req->op.open.pcm_channels = channels;
>>> + req->op.open.pcm_rate = rate;
>>> + req->op.open.buffer_sz = buffer_sz;
>>> + req->op.open.period_sz = period_sz;
>>> + req->op.open.gref_directory =
>>> xen_snd_front_shbuf_get_dir_start(sh_buf);
>>> +
>>> + ret = be_stream_do_io(evtchnl);
>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>> +
>>> + if (ret == 0)
>>> + ret = be_stream_wait_io(evtchnl);
>>> +
>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>> + return ret;
>>> +}
>>> +
>>> +int xen_snd_front_stream_close(struct xen_snd_front_evtchnl *evtchnl)
>>> +{
>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>> + struct xensnd_req *req;
>>> + unsigned long flags;
>>> + int ret;
>>> +
>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>> +
>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_CLOSE);
>>> +
>>> + ret = be_stream_do_io(evtchnl);
>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>> +
>>> + if (ret == 0)
>>> + ret = be_stream_wait_io(evtchnl);
>>> +
>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>> + return ret;
>>> +}
>>> +
>>> +int xen_snd_front_stream_write(struct xen_snd_front_evtchnl *evtchnl,
>>> + unsigned long pos, unsigned long count)
>>> +{
>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>> + struct xensnd_req *req;
>>> + unsigned long flags;
>>> + int ret;
>>> +
>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>> +
>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_WRITE);
>>> + req->op.rw.length = count;
>>> + req->op.rw.offset = pos;
>>> +
>>> + ret = be_stream_do_io(evtchnl);
>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>> +
>>> + if (ret == 0)
>>> + ret = be_stream_wait_io(evtchnl);
>>> +
>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>> + return ret;
>>> +}
>>> +
>>> +int xen_snd_front_stream_read(struct xen_snd_front_evtchnl *evtchnl,
>>> + unsigned long pos, unsigned long count)
>>> +{
>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>> + struct xensnd_req *req;
>>> + unsigned long flags;
>>> + int ret;
>>> +
>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>> +
>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_READ);
>>> + req->op.rw.length = count;
>>> + req->op.rw.offset = pos;
>>> +
>>> + ret = be_stream_do_io(evtchnl);
>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>> +
>>> + if (ret == 0)
>>> + ret = be_stream_wait_io(evtchnl);
>>> +
>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>> + return ret;
>>> +}
>>> +
>>> +int xen_snd_front_stream_trigger(struct xen_snd_front_evtchnl
>>> *evtchnl,
>>> + int type)
>>> +{
>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>> + struct xensnd_req *req;
>>> + unsigned long flags;
>>> + int ret;
>>> +
>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>> +
>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_TRIGGER);
>>> + req->op.trigger.type = type;
>>> +
>>> + ret = be_stream_do_io(evtchnl);
>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>> +
>>> + if (ret == 0)
>>> + ret = be_stream_wait_io(evtchnl);
>>> +
>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>> + return ret;
>>> +}
>>> static void xen_snd_drv_fini(struct xen_snd_front_info *front_info)
>>> {
>>> + xen_snd_front_alsa_fini(front_info);
>>> xen_snd_front_evtchnl_free_all(front_info);
>>> }
>>> @@ -45,7 +236,7 @@ static int sndback_initwait(struct
>>> xen_snd_front_info *front_info)
>>> static int sndback_connect(struct xen_snd_front_info *front_info)
>>> {
>>> - return 0;
>>> + return xen_snd_front_alsa_init(front_info);
>>> }
>>> static void sndback_disconnect(struct xen_snd_front_info
>>> *front_info)
>>> diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
>>> index 9c2ffbb4e4b8..7adbdb4d2019 100644
>>> --- a/sound/xen/xen_snd_front.h
>>> +++ b/sound/xen/xen_snd_front.h
>>> @@ -13,17 +13,45 @@
>>> #include "xen_snd_front_cfg.h"
>>> +struct card_info;
>>> +struct xen_snd_front_evtchnl;
>>> struct xen_snd_front_evtchnl_pair;
>>> +struct xen_snd_front_shbuf;
>>> +struct xensnd_query_hw_param;
>>> struct xen_snd_front_info {
>>> struct xenbus_device *xb_dev;
>>> + struct card_info *card_info;
>>> +
>>> /* serializer for backend IO: request/response */
>>> spinlock_t io_lock;
>>> +
>>> int num_evt_pairs;
>>> struct xen_snd_front_evtchnl_pair *evt_pairs;
>>> struct xen_front_cfg_card cfg;
>>> };
>>> +int xen_snd_front_stream_query_hw_param(struct
>>> xen_snd_front_evtchnl *evtchnl,
>>> + struct xensnd_query_hw_param *hw_param_req,
>>> + struct xensnd_query_hw_param *hw_param_resp);
>>> +
>>> +int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl
>>> *evtchnl,
>>> + struct xen_snd_front_shbuf *sh_buf,
>>> + u8 format, unsigned int channels,
>>> + unsigned int rate, u32 buffer_sz,
>>> + u32 period_sz);
>>> +
>>> +int xen_snd_front_stream_close(struct xen_snd_front_evtchnl *evtchnl);
>>> +
>>> +int xen_snd_front_stream_write(struct xen_snd_front_evtchnl *evtchnl,
>>> + unsigned long pos, unsigned long count);
>>> +
>>> +int xen_snd_front_stream_read(struct xen_snd_front_evtchnl *evtchnl,
>>> + unsigned long pos, unsigned long count);
>>> +
>>> +int xen_snd_front_stream_trigger(struct xen_snd_front_evtchnl
>>> *evtchnl,
>>> + int type);
>>> +
>>> #endif /* __XEN_SND_FRONT_H */
>>> diff --git a/sound/xen/xen_snd_front_alsa.c
>>> b/sound/xen/xen_snd_front_alsa.c
>>> new file mode 100644
>>> index 000000000000..f524b172750e
>>> --- /dev/null
>>> +++ b/sound/xen/xen_snd_front_alsa.c
>>> @@ -0,0 +1,830 @@
>>> +// SPDX-License-Identifier: GPL-2.0 OR MIT
>>> +
>>> +/*
>>> + * Xen para-virtual sound device
>>> + *
>>> + * Copyright (C) 2016-2018 EPAM Systems Inc.
>>> + *
>>> + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>> + */
>>> +
>>> +#include <linux/platform_device.h>
>>> +
>>> +#include <sound/core.h>
>>> +#include <sound/pcm.h>
>>> +#include <sound/pcm_params.h>
>>> +
>>> +#include <xen/xenbus.h>
>>> +
>>> +#include "xen_snd_front.h"
>>> +#include "xen_snd_front_alsa.h"
>>> +#include "xen_snd_front_cfg.h"
>>> +#include "xen_snd_front_evtchnl.h"
>>> +#include "xen_snd_front_shbuf.h"
>>> +
>>> +struct pcm_stream_info {
>> Not sure how this is generally handled in the sound drivers, but when
>> reviewing the code using those structures I repeatedly tried to find
>> their definitions in the sound headers instead of here. Same applies to
>> the alsa_* names.
>>
>> I'd prefer names which don't poison the name space.
> I'll try to do something about naming
One question still remains wrt alsa_* names: if this is for structures
I have (alsa_sndif_sample_format/alsa_sndif_hw_param), then
those already have sndif in their name which clearly says these are
Xen related ones (sndif is a Xen protocol).
If you also don't like the alsa_* function names then those are all
static and defined in this same file, so see no confusion here.
I have changed other non-obvious struct names:
-struct pcm_stream_info {
+struct xen_snd_front_pcm_stream_info {
-struct pcm_instance_info {
+struct xen_snd_front_pcm_instance_info {
-struct card_info {
+struct xen_snd_front_card_info {
Does the above work for you?
>>> + struct xen_snd_front_info *front_info;
>>> + struct xen_snd_front_evtchnl_pair *evt_pair;
>>> + struct xen_snd_front_shbuf sh_buf;
>>> + int index;
>>> +
>>> + bool is_open;
>>> + struct snd_pcm_hardware pcm_hw;
>>> +
>>> + /* number of processed frames as reported by the backend */
>>> + snd_pcm_uframes_t be_cur_frame;
>>> + /* current HW pointer to be reported via .period callback */
>>> + atomic_t hw_ptr;
>>> + /* modulo of the number of processed frames - for period
>>> detection */
>>> + u32 out_frames;
>>> +};
>>> +
>>> +struct pcm_instance_info {
>>> + struct card_info *card_info;
>>> + struct snd_pcm *pcm;
>>> + struct snd_pcm_hardware pcm_hw;
>>> + int num_pcm_streams_pb;
>>> + struct pcm_stream_info *streams_pb;
>>> + int num_pcm_streams_cap;
>>> + struct pcm_stream_info *streams_cap;
>>> +};
>>> +
>>> +struct card_info {
>>> + struct xen_snd_front_info *front_info;
>>> + struct snd_card *card;
>>> + struct snd_pcm_hardware pcm_hw;
>>> + int num_pcm_instances;
>>> + struct pcm_instance_info *pcm_instances;
>>> +};
>>> +
>>> +struct alsa_sndif_sample_format {
>>> + u8 sndif;
>>> + snd_pcm_format_t alsa;
>>> +};
>>> +
>>> +struct alsa_sndif_hw_param {
>>> + u8 sndif;
>>> + snd_pcm_hw_param_t alsa;
>>> +};
>>> +
>>> +static const struct alsa_sndif_sample_format ALSA_SNDIF_FORMATS[] = {
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_U8,
>>> + .alsa = SNDRV_PCM_FORMAT_U8
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_S8,
>>> + .alsa = SNDRV_PCM_FORMAT_S8
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_U16_LE,
>>> + .alsa = SNDRV_PCM_FORMAT_U16_LE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_U16_BE,
>>> + .alsa = SNDRV_PCM_FORMAT_U16_BE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_S16_LE,
>>> + .alsa = SNDRV_PCM_FORMAT_S16_LE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_S16_BE,
>>> + .alsa = SNDRV_PCM_FORMAT_S16_BE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_U24_LE,
>>> + .alsa = SNDRV_PCM_FORMAT_U24_LE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_U24_BE,
>>> + .alsa = SNDRV_PCM_FORMAT_U24_BE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_S24_LE,
>>> + .alsa = SNDRV_PCM_FORMAT_S24_LE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_S24_BE,
>>> + .alsa = SNDRV_PCM_FORMAT_S24_BE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_U32_LE,
>>> + .alsa = SNDRV_PCM_FORMAT_U32_LE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_U32_BE,
>>> + .alsa = SNDRV_PCM_FORMAT_U32_BE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_S32_LE,
>>> + .alsa = SNDRV_PCM_FORMAT_S32_LE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_S32_BE,
>>> + .alsa = SNDRV_PCM_FORMAT_S32_BE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_A_LAW,
>>> + .alsa = SNDRV_PCM_FORMAT_A_LAW
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_MU_LAW,
>>> + .alsa = SNDRV_PCM_FORMAT_MU_LAW
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_F32_LE,
>>> + .alsa = SNDRV_PCM_FORMAT_FLOAT_LE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_F32_BE,
>>> + .alsa = SNDRV_PCM_FORMAT_FLOAT_BE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_F64_LE,
>>> + .alsa = SNDRV_PCM_FORMAT_FLOAT64_LE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_F64_BE,
>>> + .alsa = SNDRV_PCM_FORMAT_FLOAT64_BE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE,
>>> + .alsa = SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE,
>>> + .alsa = SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_IMA_ADPCM,
>>> + .alsa = SNDRV_PCM_FORMAT_IMA_ADPCM
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_MPEG,
>>> + .alsa = SNDRV_PCM_FORMAT_MPEG
>>> + },
>>> + {
>>> + .sndif = XENSND_PCM_FORMAT_GSM,
>>> + .alsa = SNDRV_PCM_FORMAT_GSM
>>> + },
>>> +};
>>> +
>>> +static int to_sndif_format(snd_pcm_format_t format)
>>> +{
>>> + int i;
>>> +
>>> + for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
>>> + if (ALSA_SNDIF_FORMATS[i].alsa == format)
>>> + return ALSA_SNDIF_FORMATS[i].sndif;
>>> +
>>> + return -EINVAL;
>>> +}
>>> +
>>> +static u64 to_sndif_formats_mask(u64 alsa_formats)
>>> +{
>>> + u64 mask;
>>> + int i;
>>> +
>>> + mask = 0;
>>> + for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
>>> + if (1 << ALSA_SNDIF_FORMATS[i].alsa & alsa_formats)
>>> + mask |= 1 << ALSA_SNDIF_FORMATS[i].sndif;
>>> +
>>> + return mask;
>>> +}
>>> +
>>> +static u64 to_alsa_formats_mask(u64 sndif_formats)
>>> +{
>>> + u64 mask;
>>> + int i;
>>> +
>>> + mask = 0;
>>> + for (i = 0; i < ARRAY_SIZE(ALSA_SNDIF_FORMATS); i++)
>>> + if (1 << ALSA_SNDIF_FORMATS[i].sndif & sndif_formats)
>>> + mask |= 1 << ALSA_SNDIF_FORMATS[i].alsa;
>>> +
>>> + return mask;
>>> +}
>>> +
>>> +static void stream_clear(struct pcm_stream_info *stream)
>>> +{
>>> + stream->is_open = false;
>>> + stream->be_cur_frame = 0;
>>> + stream->out_frames = 0;
>>> + atomic_set(&stream->hw_ptr, 0);
>>> + xen_snd_front_evtchnl_pair_clear(stream->evt_pair);
>>> + xen_snd_front_shbuf_clear(&stream->sh_buf);
>>> +}
>>> +
>>> +static void stream_free(struct pcm_stream_info *stream)
>>> +{
>>> + xen_snd_front_shbuf_free(&stream->sh_buf);
>>> + stream_clear(stream);
>>> +}
>>> +
>>> +static struct pcm_stream_info *stream_get(struct snd_pcm_substream
>>> *substream)
>>> +{
>>> + struct pcm_instance_info *pcm_instance =
>>> + snd_pcm_substream_chip(substream);
>>> + struct pcm_stream_info *stream;
>>> +
>>> + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
>>> + stream = &pcm_instance->streams_pb[substream->number];
>>> + else
>>> + stream = &pcm_instance->streams_cap[substream->number];
>>> +
>>> + return stream;
>>> +}
>>> +
>>> +static int alsa_hw_rule(struct snd_pcm_hw_params *params,
>>> + struct snd_pcm_hw_rule *rule)
>>> +{
>>> + struct pcm_stream_info *stream = rule->private;
>>> + struct device *dev = &stream->front_info->xb_dev->dev;
>>> + struct snd_mask *formats =
>>> + hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
>>> + struct snd_interval *rates =
>>> + hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
>>> + struct snd_interval *channels =
>>> + hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
>>> + struct snd_interval *period =
>>> + hw_param_interval(params,
>>> + SNDRV_PCM_HW_PARAM_PERIOD_SIZE);
>>> + struct snd_interval *buffer =
>>> + hw_param_interval(params,
>>> + SNDRV_PCM_HW_PARAM_BUFFER_SIZE);
>>> + struct xensnd_query_hw_param req;
>>> + struct xensnd_query_hw_param resp;
>>> + struct snd_interval interval;
>>> + struct snd_mask mask;
>>> + u64 sndif_formats;
>>> + int changed, ret;
>>> +
>>> + /* collect all the values we need for the query */
>>> +
>>> + req.formats = to_sndif_formats_mask((u64)formats->bits[0] |
>>> + (u64)(formats->bits[1]) << 32);
>>> +
>>> + req.rates.min = rates->min;
>>> + req.rates.max = rates->max;
>>> +
>>> + req.channels.min = channels->min;
>>> + req.channels.max = channels->max;
>>> +
>>> + req.buffer.min = buffer->min;
>>> + req.buffer.max = buffer->max;
>>> +
>>> + req.period.min = period->min;
>>> + req.period.max = period->max;
>>> +
>>> + ret = xen_snd_front_stream_query_hw_param(&stream->evt_pair->req,
>>> + &req, &resp);
>>> + if (ret < 0) {
>>> + /* check if this is due to backend communication error */
>>> + if (ret == -EIO || ret == -ETIMEDOUT)
>>> + dev_err(dev, "Failed to query ALSA HW parameters\n");
>>> + return ret;
>>> + }
>>> +
>>> + /* refine HW parameters after the query */
>>> + changed = 0;
>>> +
>>> + sndif_formats = to_alsa_formats_mask(resp.formats);
>>> + snd_mask_none(&mask);
>>> + mask.bits[0] = (u32)sndif_formats;
>>> + mask.bits[1] = (u32)(sndif_formats >> 32);
>>> + ret = snd_mask_refine(formats, &mask);
>>> + if (ret < 0)
>>> + return ret;
>>> + changed |= ret;
>>> +
>>> + interval.openmin = 0;
>>> + interval.openmax = 0;
>>> + interval.integer = 1;
>>> +
>>> + interval.min = resp.rates.min;
>>> + interval.max = resp.rates.max;
>>> + ret = snd_interval_refine(rates, &interval);
>>> + if (ret < 0)
>>> + return ret;
>>> + changed |= ret;
>>> +
>>> + interval.min = resp.channels.min;
>>> + interval.max = resp.channels.max;
>>> + ret = snd_interval_refine(channels, &interval);
>>> + if (ret < 0)
>>> + return ret;
>>> + changed |= ret;
>>> +
>>> + interval.min = resp.buffer.min;
>>> + interval.max = resp.buffer.max;
>>> + ret = snd_interval_refine(buffer, &interval);
>>> + if (ret < 0)
>>> + return ret;
>>> + changed |= ret;
>>> +
>>> + interval.min = resp.period.min;
>>> + interval.max = resp.period.max;
>>> + ret = snd_interval_refine(period, &interval);
>>> + if (ret < 0)
>>> + return ret;
>>> + changed |= ret;
>>> +
>>> + return changed;
>>> +}
>>> +
>>> +static int alsa_open(struct snd_pcm_substream *substream)
>>> +{
>>> + struct pcm_instance_info *pcm_instance =
>>> + snd_pcm_substream_chip(substream);
>>> + struct pcm_stream_info *stream = stream_get(substream);
>>> + struct snd_pcm_runtime *runtime = substream->runtime;
>>> + struct xen_snd_front_info *front_info =
>>> + pcm_instance->card_info->front_info;
>>> + struct device *dev = &front_info->xb_dev->dev;
>>> + unsigned long flags;
>>> + int ret;
>>> +
>>> + /*
>>> + * return our HW properties: override defaults with those
>>> configured
>>> + * via XenStore
>>> + */
>>> + runtime->hw = stream->pcm_hw;
>>> + runtime->hw.info &= ~(SNDRV_PCM_INFO_MMAP |
>>> + SNDRV_PCM_INFO_MMAP_VALID |
>>> + SNDRV_PCM_INFO_DOUBLE |
>>> + SNDRV_PCM_INFO_BATCH |
>>> + SNDRV_PCM_INFO_NONINTERLEAVED |
>>> + SNDRV_PCM_INFO_RESUME |
>>> + SNDRV_PCM_INFO_PAUSE);
>>> + runtime->hw.info |= SNDRV_PCM_INFO_INTERLEAVED;
>>> +
>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>> +
>>> + stream->evt_pair = &front_info->evt_pairs[stream->index];
>>> +
>>> + stream->front_info = front_info;
>>> +
>>> + xen_snd_front_evtchnl_pair_set_connected(stream->evt_pair, true);
>>> +
>>> + stream->evt_pair->evt.u.evt.substream = substream;
>>> +
>>> + stream_clear(stream);
>>> +
>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>> +
>>> + ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
>>> + alsa_hw_rule, stream,
>>> + SNDRV_PCM_HW_PARAM_FORMAT, -1);
>>> + if (ret) {
>>> + dev_err(dev, "Failed to add HW rule for
>>> SNDRV_PCM_HW_PARAM_FORMAT\n");
>>> + return ret;
>>> + }
>>> +
>>> + ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
>>> + alsa_hw_rule, stream,
>>> + SNDRV_PCM_HW_PARAM_RATE, -1);
>>> + if (ret) {
>>> + dev_err(dev, "Failed to add HW rule for
>>> SNDRV_PCM_HW_PARAM_RATE\n");
>>> + return ret;
>>> + }
>>> +
>>> + ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
>>> + alsa_hw_rule, stream,
>>> + SNDRV_PCM_HW_PARAM_CHANNELS, -1);
>>> + if (ret) {
>>> + dev_err(dev, "Failed to add HW rule for
>>> SNDRV_PCM_HW_PARAM_CHANNELS\n");
>>> + return ret;
>>> + }
>>> +
>>> + ret = snd_pcm_hw_rule_add(runtime, 0,
>>> SNDRV_PCM_HW_PARAM_PERIOD_SIZE,
>>> + alsa_hw_rule, stream,
>>> + SNDRV_PCM_HW_PARAM_PERIOD_SIZE, -1);
>>> + if (ret) {
>>> + dev_err(dev, "Failed to add HW rule for
>>> SNDRV_PCM_HW_PARAM_PERIOD_SIZE\n");
>>> + return ret;
>>> + }
>>> +
>>> + ret = snd_pcm_hw_rule_add(runtime, 0,
>>> SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
>>> + alsa_hw_rule, stream,
>>> + SNDRV_PCM_HW_PARAM_BUFFER_SIZE, -1);
>>> + if (ret) {
>>> + dev_err(dev, "Failed to add HW rule for
>>> SNDRV_PCM_HW_PARAM_BUFFER_SIZE\n");
>>> + return ret;
>>> + }
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static int alsa_close(struct snd_pcm_substream *substream)
>>> +{
>>> + struct pcm_stream_info *stream = stream_get(substream);
>>> + unsigned long flags;
>>> +
>>> + spin_lock_irqsave(&stream->front_info->io_lock, flags);
>>> +
>>> + xen_snd_front_evtchnl_pair_set_connected(stream->evt_pair, false);
>>> +
>>> + spin_unlock_irqrestore(&stream->front_info->io_lock, flags);
>>> + return 0;
>>> +}
>>> +
>>> +static int alsa_hw_params(struct snd_pcm_substream *substream,
>>> + struct snd_pcm_hw_params *params)
>>> +{
>>> + struct pcm_stream_info *stream = stream_get(substream);
>>> + int ret;
>>> +
>>> + /*
>>> + * this callback may be called multiple times,
>>> + * so free the previously allocated shared buffer if any
>>> + */
>>> + stream_free(stream);
>>> +
>>> + ret = xen_snd_front_shbuf_alloc(stream->front_info->xb_dev,
>>> + &stream->sh_buf,
>>> + params_buffer_bytes(params));
>>> + if (ret < 0) {
>>> + stream_free(stream);
>>> + dev_err(&stream->front_info->xb_dev->dev,
>>> + "Failed to allocate buffers for stream with index %d\n",
>>> + stream->index);
>>> + return ret;
>>> + }
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static int alsa_hw_free(struct snd_pcm_substream *substream)
>>> +{
>>> + struct pcm_stream_info *stream = stream_get(substream);
>>> + int ret;
>>> +
>>> + ret = xen_snd_front_stream_close(&stream->evt_pair->req);
>>> + stream_free(stream);
>>> + return ret;
>>> +}
>>> +
>>> +static int alsa_prepare(struct snd_pcm_substream *substream)
>>> +{
>>> + struct pcm_stream_info *stream = stream_get(substream);
>>> +
>>> + if (!stream->is_open) {
>>> + struct snd_pcm_runtime *runtime = substream->runtime;
>>> + u8 sndif_format;
>>> + int ret;
>>> +
>>> + sndif_format = to_sndif_format(runtime->format);
>>> + if (sndif_format < 0) {
>>> + dev_err(&stream->front_info->xb_dev->dev,
>>> + "Unsupported sample format: %d\n",
>>> + runtime->format);
>>> + return sndif_format;
>>> + }
>>> +
>>> + ret = xen_snd_front_stream_prepare(&stream->evt_pair->req,
>>> + &stream->sh_buf,
>>> + sndif_format,
>>> + runtime->channels,
>>> + runtime->rate,
>>> + snd_pcm_lib_buffer_bytes(substream),
>>> + snd_pcm_lib_period_bytes(substream));
>>> + if (ret < 0)
>>> + return ret;
>>> +
>>> + stream->is_open = true;
>>> + }
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static int alsa_trigger(struct snd_pcm_substream *substream, int cmd)
>>> +{
>>> + struct pcm_stream_info *stream = stream_get(substream);
>>> + int type;
>>> +
>>> + switch (cmd) {
>>> + case SNDRV_PCM_TRIGGER_START:
>>> + type = XENSND_OP_TRIGGER_START;
>>> + break;
>>> +
>>> + case SNDRV_PCM_TRIGGER_RESUME:
>>> + type = XENSND_OP_TRIGGER_RESUME;
>>> + break;
>>> +
>>> + case SNDRV_PCM_TRIGGER_STOP:
>>> + type = XENSND_OP_TRIGGER_STOP;
>>> + break;
>>> +
>>> + case SNDRV_PCM_TRIGGER_SUSPEND:
>>> + type = XENSND_OP_TRIGGER_PAUSE;
>>> + break;
>>> +
>>> + default:
>>> + return -EINVAL;
>>> + }
>>> +
>>> + return xen_snd_front_stream_trigger(&stream->evt_pair->req, type);
>>> +}
>>> +
>>> +void xen_snd_front_alsa_handle_cur_pos(struct xen_snd_front_evtchnl
>>> *evtchnl,
>>> + u64 pos_bytes)
>>> +{
>>> + struct snd_pcm_substream *substream = evtchnl->u.evt.substream;
>>> + struct pcm_stream_info *stream = stream_get(substream);
>>> + snd_pcm_uframes_t delta, new_hw_ptr, cur_frame;
>>> +
>>> + cur_frame = bytes_to_frames(substream->runtime, pos_bytes);
>>> +
>>> + delta = cur_frame - stream->be_cur_frame;
>>> + stream->be_cur_frame = cur_frame;
>>> +
>>> + new_hw_ptr = (snd_pcm_uframes_t)atomic_read(&stream->hw_ptr);
>>> + new_hw_ptr = (new_hw_ptr + delta) %
>>> substream->runtime->buffer_size;
>>> + atomic_set(&stream->hw_ptr, (int)new_hw_ptr);
>>> +
>>> + stream->out_frames += delta;
>>> + if (stream->out_frames > substream->runtime->period_size) {
>>> + stream->out_frames %= substream->runtime->period_size;
>>> + snd_pcm_period_elapsed(substream);
>>> + }
>>> +}
>>> +
>>> +static snd_pcm_uframes_t alsa_pointer(struct snd_pcm_substream
>>> *substream)
>>> +{
>>> + struct pcm_stream_info *stream = stream_get(substream);
>>> +
>>> + return (snd_pcm_uframes_t)atomic_read(&stream->hw_ptr);
>>> +}
>>> +
>>> +static int alsa_pb_copy_user(struct snd_pcm_substream *substream,
>>> + int channel, unsigned long pos, void __user *src,
>>> + unsigned long count)
>>> +{
>>> + struct pcm_stream_info *stream = stream_get(substream);
>>> +
>>> + if (unlikely(pos + count > stream->sh_buf.buffer_sz))
>>> + return -EINVAL;
>>> +
>>> + if (copy_from_user(stream->sh_buf.buffer + pos, src, count))
>>> + return -EFAULT;
>>> +
>>> + return xen_snd_front_stream_write(&stream->evt_pair->req, pos,
>>> count);
>>> +}
>>> +
>>> +static int alsa_pb_copy_kernel(struct snd_pcm_substream *substream,
>>> + int channel, unsigned long pos, void *src,
>>> + unsigned long count)
>>> +{
>>> + struct pcm_stream_info *stream = stream_get(substream);
>>> +
>>> + if (unlikely(pos + count > stream->sh_buf.buffer_sz))
>>> + return -EINVAL;
>>> +
>>> + memcpy(stream->sh_buf.buffer + pos, src, count);
>>> +
>>> + return xen_snd_front_stream_write(&stream->evt_pair->req, pos,
>>> count);
>>> +}
>>> +
>>> +static int alsa_cap_copy_user(struct snd_pcm_substream *substream,
>>> + int channel, unsigned long pos, void __user *dst,
>>> + unsigned long count)
>>> +{
>>> + struct pcm_stream_info *stream = stream_get(substream);
>>> + int ret;
>>> +
>>> + if (unlikely(pos + count > stream->sh_buf.buffer_sz))
>>> + return -EINVAL;
>>> +
>>> + ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos,
>>> count);
>>> + if (ret < 0)
>>> + return ret;
>>> +
>>> + return copy_to_user(dst, stream->sh_buf.buffer + pos, count) ?
>>> + -EFAULT : 0;
>>> +}
>>> +
>>> +static int alsa_cap_copy_kernel(struct snd_pcm_substream *substream,
>>> + int channel, unsigned long pos, void *dst,
>>> + unsigned long count)
>>> +{
>>> + struct pcm_stream_info *stream = stream_get(substream);
>>> + int ret;
>>> +
>>> + if (unlikely(pos + count > stream->sh_buf.buffer_sz))
>>> + return -EINVAL;
>>> +
>>> + ret = xen_snd_front_stream_read(&stream->evt_pair->req, pos,
>>> count);
>>> + if (ret < 0)
>>> + return ret;
>>> +
>>> + memcpy(dst, stream->sh_buf.buffer + pos, count);
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static int alsa_pb_fill_silence(struct snd_pcm_substream *substream,
>>> + int channel, unsigned long pos,
>>> + unsigned long count)
>>> +{
>>> + struct pcm_stream_info *stream = stream_get(substream);
>>> +
>>> + if (unlikely(pos + count > stream->sh_buf.buffer_sz))
>>> + return -EINVAL;
>>> +
>>> + memset(stream->sh_buf.buffer + pos, 0, count);
>>> +
>>> + return xen_snd_front_stream_write(&stream->evt_pair->req, pos,
>>> count);
>>> +}
>>> +
>>> +/*
>>> + * FIXME: The mmaped data transfer is asynchronous and there is no
>>> + * ack signal from user-space when it is done. This is the
>>> + * reason it is not implemented in the PV driver as we do need
>>> + * to know when the buffer can be transferred to the backend.
>>> + */
>>> +
>>> +static struct snd_pcm_ops snd_drv_alsa_playback_ops = {
>>> + .open = alsa_open,
>>> + .close = alsa_close,
>>> + .ioctl = snd_pcm_lib_ioctl,
>>> + .hw_params = alsa_hw_params,
>>> + .hw_free = alsa_hw_free,
>>> + .prepare = alsa_prepare,
>>> + .trigger = alsa_trigger,
>>> + .pointer = alsa_pointer,
>>> + .copy_user = alsa_pb_copy_user,
>>> + .copy_kernel = alsa_pb_copy_kernel,
>>> + .fill_silence = alsa_pb_fill_silence,
>>> +};
>>> +
>>> +static struct snd_pcm_ops snd_drv_alsa_capture_ops = {
>>> + .open = alsa_open,
>>> + .close = alsa_close,
>>> + .ioctl = snd_pcm_lib_ioctl,
>>> + .hw_params = alsa_hw_params,
>>> + .hw_free = alsa_hw_free,
>>> + .prepare = alsa_prepare,
>>> + .trigger = alsa_trigger,
>>> + .pointer = alsa_pointer,
>>> + .copy_user = alsa_cap_copy_user,
>>> + .copy_kernel = alsa_cap_copy_kernel,
>>> +};
>>> +
>>> +static int new_pcm_instance(struct card_info *card_info,
>>> + struct xen_front_cfg_pcm_instance *instance_cfg,
>>> + struct pcm_instance_info *pcm_instance_info)
>>> +{
>>> + struct snd_pcm *pcm;
>>> + int ret, i;
>>> +
>>> + dev_dbg(&card_info->front_info->xb_dev->dev,
>>> + "New PCM device \"%s\" with id %d playback %d capture %d",
>>> + instance_cfg->name,
>>> + instance_cfg->device_id,
>>> + instance_cfg->num_streams_pb,
>>> + instance_cfg->num_streams_cap);
>>> +
>>> + pcm_instance_info->card_info = card_info;
>>> +
>>> + pcm_instance_info->pcm_hw = instance_cfg->pcm_hw;
>>> +
>>> + if (instance_cfg->num_streams_pb) {
>>> + pcm_instance_info->streams_pb =
>>> + devm_kcalloc(&card_info->card->card_dev,
>>> + instance_cfg->num_streams_pb,
>>> + sizeof(struct pcm_stream_info),
>>> + GFP_KERNEL);
>>> + if (!pcm_instance_info->streams_pb)
>>> + return -ENOMEM;
>>> + }
>>> +
>>> + if (instance_cfg->num_streams_cap) {
>>> + pcm_instance_info->streams_cap =
>>> + devm_kcalloc(&card_info->card->card_dev,
>>> + instance_cfg->num_streams_cap,
>>> + sizeof(struct pcm_stream_info),
>>> + GFP_KERNEL);
>>> + if (!pcm_instance_info->streams_cap)
>>> + return -ENOMEM;
>>> + }
>>> +
>>> + pcm_instance_info->num_pcm_streams_pb =
>>> + instance_cfg->num_streams_pb;
>>> + pcm_instance_info->num_pcm_streams_cap =
>>> + instance_cfg->num_streams_cap;
>>> +
>>> + for (i = 0; i < pcm_instance_info->num_pcm_streams_pb; i++) {
>>> + pcm_instance_info->streams_pb[i].pcm_hw =
>>> + instance_cfg->streams_pb[i].pcm_hw;
>>> + pcm_instance_info->streams_pb[i].index =
>>> + instance_cfg->streams_pb[i].index;
>>> + }
>>> +
>>> + for (i = 0; i < pcm_instance_info->num_pcm_streams_cap; i++) {
>>> + pcm_instance_info->streams_cap[i].pcm_hw =
>>> + instance_cfg->streams_cap[i].pcm_hw;
>>> + pcm_instance_info->streams_cap[i].index =
>>> + instance_cfg->streams_cap[i].index;
>>> + }
>>> +
>>> + ret = snd_pcm_new(card_info->card, instance_cfg->name,
>>> + instance_cfg->device_id,
>>> + instance_cfg->num_streams_pb,
>>> + instance_cfg->num_streams_cap,
>>> + &pcm);
>>> + if (ret < 0)
>>> + return ret;
>>> +
>>> + pcm->private_data = pcm_instance_info;
>>> + pcm->info_flags = 0;
>>> + /* we want to handle all PCM operations in non-atomic context */
>>> + pcm->nonatomic = true;
>>> + strncpy(pcm->name, "Virtual card PCM", sizeof(pcm->name));
>>> +
>>> + if (instance_cfg->num_streams_pb)
>>> + snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
>>> + &snd_drv_alsa_playback_ops);
>>> +
>>> + if (instance_cfg->num_streams_cap)
>>> + snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,
>>> + &snd_drv_alsa_capture_ops);
>>> +
>>> + pcm_instance_info->pcm = pcm;
>>> + return 0;
>>> +}
>>> +
>>> +int xen_snd_front_alsa_init(struct xen_snd_front_info *front_info)
>>> +{
>>> + struct device *dev = &front_info->xb_dev->dev;
>>> + struct xen_front_cfg_card *cfg = &front_info->cfg;
>>> + struct card_info *card_info;
>>> + struct snd_card *card;
>>> + int ret, i;
>>> +
>>> + dev_dbg(dev, "Creating virtual sound card\n");
>>> +
>>> + ret = snd_card_new(dev, 0, XENSND_DRIVER_NAME, THIS_MODULE,
>>> + sizeof(struct card_info), &card);
>>> + if (ret < 0)
>>> + return ret;
>>> +
>>> + card_info = card->private_data;
>>> + card_info->front_info = front_info;
>>> + front_info->card_info = card_info;
>>> + card_info->card = card;
>>> + card_info->pcm_instances =
>>> + devm_kcalloc(dev, cfg->num_pcm_instances,
>>> + sizeof(struct pcm_instance_info),
>>> + GFP_KERNEL);
>>> + if (!card_info->pcm_instances) {
>>> + ret = -ENOMEM;
>>> + goto fail;
>>> + }
>>> +
>>> + card_info->num_pcm_instances = cfg->num_pcm_instances;
>>> + card_info->pcm_hw = cfg->pcm_hw;
>>> +
>>> + for (i = 0; i < cfg->num_pcm_instances; i++) {
>>> + ret = new_pcm_instance(card_info, &cfg->pcm_instances[i],
>>> + &card_info->pcm_instances[i]);
>>> + if (ret < 0)
>>> + goto fail;
>>> + }
>>> +
>>> + strncpy(card->driver, XENSND_DRIVER_NAME, sizeof(card->driver));
>>> + strncpy(card->shortname, cfg->name_short,
>>> sizeof(card->shortname));
>>> + strncpy(card->longname, cfg->name_long, sizeof(card->longname));
>>> +
>>> + ret = snd_card_register(card);
>>> + if (ret < 0)
>>> + goto fail;
>>> +
>>> + return 0;
>>> +
>>> +fail:
>>> + snd_card_free(card);
>>> + return ret;
>>> +}
>>> +
>>> +void xen_snd_front_alsa_fini(struct xen_snd_front_info *front_info)
>>> +{
>>> + struct card_info *card_info;
>>> + struct snd_card *card;
>>> +
>>> + card_info = front_info->card_info;
>>> + if (!card_info)
>>> + return;
>>> +
>>> + card = card_info->card;
>>> + if (!card)
>>> + return;
>>> +
>>> + dev_dbg(&front_info->xb_dev->dev, "Removing virtual sound card
>>> %d\n",
>>> + card->number);
>>> + snd_card_free(card);
>>> +
>>> + /* card_info will be freed when destroying
>>> front_info->xb_dev->dev */
>>> + card_info->card = NULL;
>>> +}
>>> diff --git a/sound/xen/xen_snd_front_alsa.h
>>> b/sound/xen/xen_snd_front_alsa.h
>>> new file mode 100644
>>> index 000000000000..18abd9eec967
>>> --- /dev/null
>>> +++ b/sound/xen/xen_snd_front_alsa.h
>>> @@ -0,0 +1,23 @@
>>> +/* SPDX-License-Identifier: GPL-2.0 OR MIT */
>>> +
>>> +/*
>>> + * Xen para-virtual sound device
>>> + *
>>> + * Copyright (C) 2016-2018 EPAM Systems Inc.
>>> + *
>>> + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>> + */
>>> +
>>> +#ifndef __XEN_SND_FRONT_ALSA_H
>>> +#define __XEN_SND_FRONT_ALSA_H
>>> +
>>> +struct xen_snd_front_info;
>>> +
>>> +int xen_snd_front_alsa_init(struct xen_snd_front_info *front_info);
>>> +
>>> +void xen_snd_front_alsa_fini(struct xen_snd_front_info *front_info);
>>> +
>>> +void xen_snd_front_alsa_handle_cur_pos(struct xen_snd_front_evtchnl
>>> *evtchnl,
>>> + u64 pos_bytes);
>>> +
>>> +#endif /* __XEN_SND_FRONT_ALSA_H */
>>> diff --git a/sound/xen/xen_snd_front_evtchnl.c
>>> b/sound/xen/xen_snd_front_evtchnl.c
>>> index 9ece39f938f8..470196518716 100644
>>> --- a/sound/xen/xen_snd_front_evtchnl.c
>>> +++ b/sound/xen/xen_snd_front_evtchnl.c
>>> @@ -14,6 +14,7 @@
>>> #include <xen/xenbus.h>
>>> #include "xen_snd_front.h"
>>> +#include "xen_snd_front_alsa.h"
>>> #include "xen_snd_front_cfg.h"
>>> #include "xen_snd_front_evtchnl.h"
>>> @@ -111,7 +112,10 @@ static irqreturn_t evtchnl_interrupt_evt(int
>>> irq, void *dev_id)
>>> switch (event->type) {
>>> case XENSND_EVT_CUR_POS:
>>> - /* do nothing at the moment */
>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>> + xen_snd_front_alsa_handle_cur_pos(channel,
>>> + event->op.cur_pos.position);
>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>> Is this correct? Why can you free the lock here without doing any
>> harm? What is the lock protecting? I'd like to see at least some
>> comments explaining why the lock is needed and why it can be dropped
>> here.
> Well, this code has issues and will be re-worked:
> 1. Which locks I need:
> 1.1. lock to serialize requests to backend
> 1.2. lock to protect the ring: between requests code and interrupt
> handler
>
> 2. I don't really need a spinlock here b/c interrupts are threaded,
> so I can safely use a mutex: thus no need for fancy code with unlocking
> and locking again while servicing xen_snd_front_alsa_handle_cur_pos
>
> Thank you
>>
>> Juergen
>
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 5/5] ALSA: xen-front: Implement ALSA virtual sound driver
2018-04-17 12:26 ` Oleksandr Andrushchenko
@ 2018-04-17 12:32 ` Juergen Gross
2018-04-17 12:34 ` Oleksandr Andrushchenko
0 siblings, 1 reply; 40+ messages in thread
From: Juergen Gross @ 2018-04-17 12:32 UTC (permalink / raw)
To: Oleksandr Andrushchenko, xen-devel, linux-kernel, alsa-devel,
boris.ostrovsky, konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 17/04/18 14:26, Oleksandr Andrushchenko wrote:
> On 04/17/2018 02:32 PM, Oleksandr Andrushchenko wrote:
>> On 04/16/2018 05:09 PM, Juergen Gross wrote:
>>> On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
>>>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>>>
>>>> Implement essential initialization of the sound driver:
>>>> - introduce required data structures
>>>> - handle driver registration
>>>> - handle sound card registration
>>>> - register sound driver on backend connection
>>>> - remove sound driver on backend disconnect
>>>>
>>>> Initialize virtual sound card with streams according to the
>>>> Xen store configuration.
>>>>
>>>> Implement ALSA driver operations including:
>>>> - manage frontend/backend shared buffers
>>>> - manage Xen bus event channel states
>>>>
>>>> Implement requests from front to back for ALSA
>>>> PCM operations.
>>>> - report ALSA period elapsed event: handle XENSND_EVT_CUR_POS
>>>> notifications from the backend when stream position advances
>>>> during playback/capture. The event carries a value of how
>>>> many octets were played/captured at the time of the event.
>>>> - implement explicit stream parameter negotiation between
>>>> backend and frontend: handle XENSND_OP_HW_PARAM_QUERY request
>>>> to read/update configuration space for the parameter given:
>>>> request passes desired parameter interval and the response to
>>>> this request returns min/max interval for the parameter to be used.
>>>>
>>>> Signed-off-by: Oleksandr Andrushchenko
>>>> <oleksandr_andrushchenko@epam.com>
>>>> ---
>>>> sound/xen/Makefile | 3 +-
>>>> sound/xen/xen_snd_front.c | 193 ++++++++-
>>>> sound/xen/xen_snd_front.h | 28 ++
>>>> sound/xen/xen_snd_front_alsa.c | 830
>>>> ++++++++++++++++++++++++++++++++++++++
>>>> sound/xen/xen_snd_front_alsa.h | 23 ++
>>>> sound/xen/xen_snd_front_evtchnl.c | 6 +-
>>>> 6 files changed, 1080 insertions(+), 3 deletions(-)
>>>> create mode 100644 sound/xen/xen_snd_front_alsa.c
>>>> create mode 100644 sound/xen/xen_snd_front_alsa.h
>>>>
>>>> diff --git a/sound/xen/Makefile b/sound/xen/Makefile
>>>> index f028bc30af5d..1e6470ecc2f2 100644
>>>> --- a/sound/xen/Makefile
>>>> +++ b/sound/xen/Makefile
>>>> @@ -3,6 +3,7 @@
>>>> snd_xen_front-objs := xen_snd_front.o \
>>>> xen_snd_front_cfg.o \
>>>> xen_snd_front_evtchnl.o \
>>>> - xen_snd_front_shbuf.o
>>>> + xen_snd_front_shbuf.o \
>>>> + xen_snd_front_alsa.o
>>>> obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
>>>> diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
>>>> index 0569c6c596a3..1fef253ea21a 100644
>>>> --- a/sound/xen/xen_snd_front.c
>>>> +++ b/sound/xen/xen_snd_front.c
>>>> @@ -19,10 +19,201 @@
>>>> #include <xen/interface/io/sndif.h>
>>>> #include "xen_snd_front.h"
>>>> +#include "xen_snd_front_alsa.h"
>>>> #include "xen_snd_front_evtchnl.h"
>>>> +#include "xen_snd_front_shbuf.h"
>>>> +
>>>> +static struct xensnd_req *
>>>> +be_stream_prepare_req(struct xen_snd_front_evtchnl *evtchnl, u8
>>>> operation)
>>>> +{
>>>> + struct xensnd_req *req;
>>>> +
>>>> + req = RING_GET_REQUEST(&evtchnl->u.req.ring,
>>>> + evtchnl->u.req.ring.req_prod_pvt);
>>>> + req->operation = operation;
>>>> + req->id = evtchnl->evt_next_id++;
>>>> + evtchnl->evt_id = req->id;
>>>> + return req;
>>>> +}
>>>> +
>>>> +static int be_stream_do_io(struct xen_snd_front_evtchnl *evtchnl)
>>>> +{
>>>> + if (unlikely(evtchnl->state != EVTCHNL_STATE_CONNECTED))
>>>> + return -EIO;
>>>> +
>>>> + reinit_completion(&evtchnl->u.req.completion);
>>>> + xen_snd_front_evtchnl_flush(evtchnl);
>>>> + return 0;
>>>> +}
>>>> +
>>>> +static int be_stream_wait_io(struct xen_snd_front_evtchnl *evtchnl)
>>>> +{
>>>> + if (wait_for_completion_timeout(&evtchnl->u.req.completion,
>>>> + msecs_to_jiffies(VSND_WAIT_BACK_MS)) <= 0)
>>>> + return -ETIMEDOUT;
>>>> +
>>>> + return evtchnl->u.req.resp_status;
>>>> +}
>>>> +
>>>> +int xen_snd_front_stream_query_hw_param(struct
>>>> xen_snd_front_evtchnl *evtchnl,
>>>> + struct xensnd_query_hw_param *hw_param_req,
>>>> + struct xensnd_query_hw_param *hw_param_resp)
>>>> +{
>>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>>> + struct xensnd_req *req;
>>>> + unsigned long flags;
>>>> + int ret;
>>>> +
>>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>>> +
>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_HW_PARAM_QUERY);
>>>> + req->op.hw_param = *hw_param_req;
>>>> +
>>>> + ret = be_stream_do_io(evtchnl);
>>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>>> +
>>>> + if (ret == 0)
>>>> + ret = be_stream_wait_io(evtchnl);
>>>> +
>>>> + if (ret == 0)
>>>> + *hw_param_resp = evtchnl->u.req.resp.hw_param;
>>>> +
>>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>>> + return ret;
>>>> +}
>>>> +
>>>> +int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl
>>>> *evtchnl,
>>>> + struct xen_snd_front_shbuf *sh_buf,
>>>> + u8 format, unsigned int channels,
>>>> + unsigned int rate, u32 buffer_sz,
>>>> + u32 period_sz)
>>>> +{
>>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>>> + struct xensnd_req *req;
>>>> + unsigned long flags;
>>>> + int ret;
>>>> +
>>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>>> +
>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_OPEN);
>>>> + req->op.open.pcm_format = format;
>>>> + req->op.open.pcm_channels = channels;
>>>> + req->op.open.pcm_rate = rate;
>>>> + req->op.open.buffer_sz = buffer_sz;
>>>> + req->op.open.period_sz = period_sz;
>>>> + req->op.open.gref_directory =
>>>> xen_snd_front_shbuf_get_dir_start(sh_buf);
>>>> +
>>>> + ret = be_stream_do_io(evtchnl);
>>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>>> +
>>>> + if (ret == 0)
>>>> + ret = be_stream_wait_io(evtchnl);
>>>> +
>>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>>> + return ret;
>>>> +}
>>>> +
>>>> +int xen_snd_front_stream_close(struct xen_snd_front_evtchnl *evtchnl)
>>>> +{
>>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>>> + struct xensnd_req *req;
>>>> + unsigned long flags;
>>>> + int ret;
>>>> +
>>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>>> +
>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_CLOSE);
>>>> +
>>>> + ret = be_stream_do_io(evtchnl);
>>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>>> +
>>>> + if (ret == 0)
>>>> + ret = be_stream_wait_io(evtchnl);
>>>> +
>>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>>> + return ret;
>>>> +}
>>>> +
>>>> +int xen_snd_front_stream_write(struct xen_snd_front_evtchnl *evtchnl,
>>>> + unsigned long pos, unsigned long count)
>>>> +{
>>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>>> + struct xensnd_req *req;
>>>> + unsigned long flags;
>>>> + int ret;
>>>> +
>>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>>> +
>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_WRITE);
>>>> + req->op.rw.length = count;
>>>> + req->op.rw.offset = pos;
>>>> +
>>>> + ret = be_stream_do_io(evtchnl);
>>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>>> +
>>>> + if (ret == 0)
>>>> + ret = be_stream_wait_io(evtchnl);
>>>> +
>>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>>> + return ret;
>>>> +}
>>>> +
>>>> +int xen_snd_front_stream_read(struct xen_snd_front_evtchnl *evtchnl,
>>>> + unsigned long pos, unsigned long count)
>>>> +{
>>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>>> + struct xensnd_req *req;
>>>> + unsigned long flags;
>>>> + int ret;
>>>> +
>>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>>> +
>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_READ);
>>>> + req->op.rw.length = count;
>>>> + req->op.rw.offset = pos;
>>>> +
>>>> + ret = be_stream_do_io(evtchnl);
>>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>>> +
>>>> + if (ret == 0)
>>>> + ret = be_stream_wait_io(evtchnl);
>>>> +
>>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>>> + return ret;
>>>> +}
>>>> +
>>>> +int xen_snd_front_stream_trigger(struct xen_snd_front_evtchnl
>>>> *evtchnl,
>>>> + int type)
>>>> +{
>>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>>> + struct xensnd_req *req;
>>>> + unsigned long flags;
>>>> + int ret;
>>>> +
>>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>>> +
>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_TRIGGER);
>>>> + req->op.trigger.type = type;
>>>> +
>>>> + ret = be_stream_do_io(evtchnl);
>>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>>> +
>>>> + if (ret == 0)
>>>> + ret = be_stream_wait_io(evtchnl);
>>>> +
>>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>>> + return ret;
>>>> +}
>>>> static void xen_snd_drv_fini(struct xen_snd_front_info *front_info)
>>>> {
>>>> + xen_snd_front_alsa_fini(front_info);
>>>> xen_snd_front_evtchnl_free_all(front_info);
>>>> }
>>>> @@ -45,7 +236,7 @@ static int sndback_initwait(struct
>>>> xen_snd_front_info *front_info)
>>>> static int sndback_connect(struct xen_snd_front_info *front_info)
>>>> {
>>>> - return 0;
>>>> + return xen_snd_front_alsa_init(front_info);
>>>> }
>>>> static void sndback_disconnect(struct xen_snd_front_info
>>>> *front_info)
>>>> diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
>>>> index 9c2ffbb4e4b8..7adbdb4d2019 100644
>>>> --- a/sound/xen/xen_snd_front.h
>>>> +++ b/sound/xen/xen_snd_front.h
>>>> @@ -13,17 +13,45 @@
>>>> #include "xen_snd_front_cfg.h"
>>>> +struct card_info;
>>>> +struct xen_snd_front_evtchnl;
>>>> struct xen_snd_front_evtchnl_pair;
>>>> +struct xen_snd_front_shbuf;
>>>> +struct xensnd_query_hw_param;
>>>> struct xen_snd_front_info {
>>>> struct xenbus_device *xb_dev;
>>>> + struct card_info *card_info;
>>>> +
>>>> /* serializer for backend IO: request/response */
>>>> spinlock_t io_lock;
>>>> +
>>>> int num_evt_pairs;
>>>> struct xen_snd_front_evtchnl_pair *evt_pairs;
>>>> struct xen_front_cfg_card cfg;
>>>> };
>>>> +int xen_snd_front_stream_query_hw_param(struct
>>>> xen_snd_front_evtchnl *evtchnl,
>>>> + struct xensnd_query_hw_param *hw_param_req,
>>>> + struct xensnd_query_hw_param *hw_param_resp);
>>>> +
>>>> +int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl
>>>> *evtchnl,
>>>> + struct xen_snd_front_shbuf *sh_buf,
>>>> + u8 format, unsigned int channels,
>>>> + unsigned int rate, u32 buffer_sz,
>>>> + u32 period_sz);
>>>> +
>>>> +int xen_snd_front_stream_close(struct xen_snd_front_evtchnl *evtchnl);
>>>> +
>>>> +int xen_snd_front_stream_write(struct xen_snd_front_evtchnl *evtchnl,
>>>> + unsigned long pos, unsigned long count);
>>>> +
>>>> +int xen_snd_front_stream_read(struct xen_snd_front_evtchnl *evtchnl,
>>>> + unsigned long pos, unsigned long count);
>>>> +
>>>> +int xen_snd_front_stream_trigger(struct xen_snd_front_evtchnl
>>>> *evtchnl,
>>>> + int type);
>>>> +
>>>> #endif /* __XEN_SND_FRONT_H */
>>>> diff --git a/sound/xen/xen_snd_front_alsa.c
>>>> b/sound/xen/xen_snd_front_alsa.c
>>>> new file mode 100644
>>>> index 000000000000..f524b172750e
>>>> --- /dev/null
>>>> +++ b/sound/xen/xen_snd_front_alsa.c
>>>> @@ -0,0 +1,830 @@
>>>> +// SPDX-License-Identifier: GPL-2.0 OR MIT
>>>> +
>>>> +/*
>>>> + * Xen para-virtual sound device
>>>> + *
>>>> + * Copyright (C) 2016-2018 EPAM Systems Inc.
>>>> + *
>>>> + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>>> + */
>>>> +
>>>> +#include <linux/platform_device.h>
>>>> +
>>>> +#include <sound/core.h>
>>>> +#include <sound/pcm.h>
>>>> +#include <sound/pcm_params.h>
>>>> +
>>>> +#include <xen/xenbus.h>
>>>> +
>>>> +#include "xen_snd_front.h"
>>>> +#include "xen_snd_front_alsa.h"
>>>> +#include "xen_snd_front_cfg.h"
>>>> +#include "xen_snd_front_evtchnl.h"
>>>> +#include "xen_snd_front_shbuf.h"
>>>> +
>>>> +struct pcm_stream_info {
>>> Not sure how this is generally handled in the sound drivers, but when
>>> reviewing the code using those structures I repeatedly tried to find
>>> their definitions in the sound headers instead of here. Same applies to
>>> the alsa_* names.
>>>
>>> I'd prefer names which don't poison the name space.
>> I'll try to do something about naming
> One question still remains wrt alsa_* names: if this is for structures
> I have (alsa_sndif_sample_format/alsa_sndif_hw_param), then
> those already have sndif in their name which clearly says these are
> Xen related ones (sndif is a Xen protocol).
> If you also don't like the alsa_* function names then those are all
> static and defined in this same file, so see no confusion here.
>
> I have changed other non-obvious struct names:
>
> -struct pcm_stream_info {
> +struct xen_snd_front_pcm_stream_info {
>
> -struct pcm_instance_info {
> +struct xen_snd_front_pcm_instance_info {
>
> -struct card_info {
> +struct xen_snd_front_card_info {
>
> Does the above work for you?
Yes, this seems to be okay.
Thanks,
Juergen
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 5/5] ALSA: xen-front: Implement ALSA virtual sound driver
2018-04-17 12:32 ` Juergen Gross
@ 2018-04-17 12:34 ` Oleksandr Andrushchenko
0 siblings, 0 replies; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-17 12:34 UTC (permalink / raw)
To: Juergen Gross, Oleksandr Andrushchenko, xen-devel, linux-kernel,
alsa-devel, boris.ostrovsky, konrad.wilk, perex, tiwai
On 04/17/2018 03:32 PM, Juergen Gross wrote:
> On 17/04/18 14:26, Oleksandr Andrushchenko wrote:
>> On 04/17/2018 02:32 PM, Oleksandr Andrushchenko wrote:
>>> On 04/16/2018 05:09 PM, Juergen Gross wrote:
>>>> On 16/04/18 08:24, Oleksandr Andrushchenko wrote:
>>>>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>>>>
>>>>> Implement essential initialization of the sound driver:
>>>>> - introduce required data structures
>>>>> - handle driver registration
>>>>> - handle sound card registration
>>>>> - register sound driver on backend connection
>>>>> - remove sound driver on backend disconnect
>>>>>
>>>>> Initialize virtual sound card with streams according to the
>>>>> Xen store configuration.
>>>>>
>>>>> Implement ALSA driver operations including:
>>>>> - manage frontend/backend shared buffers
>>>>> - manage Xen bus event channel states
>>>>>
>>>>> Implement requests from front to back for ALSA
>>>>> PCM operations.
>>>>> - report ALSA period elapsed event: handle XENSND_EVT_CUR_POS
>>>>> notifications from the backend when stream position advances
>>>>> during playback/capture. The event carries a value of how
>>>>> many octets were played/captured at the time of the event.
>>>>> - implement explicit stream parameter negotiation between
>>>>> backend and frontend: handle XENSND_OP_HW_PARAM_QUERY request
>>>>> to read/update configuration space for the parameter given:
>>>>> request passes desired parameter interval and the response to
>>>>> this request returns min/max interval for the parameter to be used.
>>>>>
>>>>> Signed-off-by: Oleksandr Andrushchenko
>>>>> <oleksandr_andrushchenko@epam.com>
>>>>> ---
>>>>> sound/xen/Makefile | 3 +-
>>>>> sound/xen/xen_snd_front.c | 193 ++++++++-
>>>>> sound/xen/xen_snd_front.h | 28 ++
>>>>> sound/xen/xen_snd_front_alsa.c | 830
>>>>> ++++++++++++++++++++++++++++++++++++++
>>>>> sound/xen/xen_snd_front_alsa.h | 23 ++
>>>>> sound/xen/xen_snd_front_evtchnl.c | 6 +-
>>>>> 6 files changed, 1080 insertions(+), 3 deletions(-)
>>>>> create mode 100644 sound/xen/xen_snd_front_alsa.c
>>>>> create mode 100644 sound/xen/xen_snd_front_alsa.h
>>>>>
>>>>> diff --git a/sound/xen/Makefile b/sound/xen/Makefile
>>>>> index f028bc30af5d..1e6470ecc2f2 100644
>>>>> --- a/sound/xen/Makefile
>>>>> +++ b/sound/xen/Makefile
>>>>> @@ -3,6 +3,7 @@
>>>>> snd_xen_front-objs := xen_snd_front.o \
>>>>> xen_snd_front_cfg.o \
>>>>> xen_snd_front_evtchnl.o \
>>>>> - xen_snd_front_shbuf.o
>>>>> + xen_snd_front_shbuf.o \
>>>>> + xen_snd_front_alsa.o
>>>>> obj-$(CONFIG_SND_XEN_FRONTEND) += snd_xen_front.o
>>>>> diff --git a/sound/xen/xen_snd_front.c b/sound/xen/xen_snd_front.c
>>>>> index 0569c6c596a3..1fef253ea21a 100644
>>>>> --- a/sound/xen/xen_snd_front.c
>>>>> +++ b/sound/xen/xen_snd_front.c
>>>>> @@ -19,10 +19,201 @@
>>>>> #include <xen/interface/io/sndif.h>
>>>>> #include "xen_snd_front.h"
>>>>> +#include "xen_snd_front_alsa.h"
>>>>> #include "xen_snd_front_evtchnl.h"
>>>>> +#include "xen_snd_front_shbuf.h"
>>>>> +
>>>>> +static struct xensnd_req *
>>>>> +be_stream_prepare_req(struct xen_snd_front_evtchnl *evtchnl, u8
>>>>> operation)
>>>>> +{
>>>>> + struct xensnd_req *req;
>>>>> +
>>>>> + req = RING_GET_REQUEST(&evtchnl->u.req.ring,
>>>>> + evtchnl->u.req.ring.req_prod_pvt);
>>>>> + req->operation = operation;
>>>>> + req->id = evtchnl->evt_next_id++;
>>>>> + evtchnl->evt_id = req->id;
>>>>> + return req;
>>>>> +}
>>>>> +
>>>>> +static int be_stream_do_io(struct xen_snd_front_evtchnl *evtchnl)
>>>>> +{
>>>>> + if (unlikely(evtchnl->state != EVTCHNL_STATE_CONNECTED))
>>>>> + return -EIO;
>>>>> +
>>>>> + reinit_completion(&evtchnl->u.req.completion);
>>>>> + xen_snd_front_evtchnl_flush(evtchnl);
>>>>> + return 0;
>>>>> +}
>>>>> +
>>>>> +static int be_stream_wait_io(struct xen_snd_front_evtchnl *evtchnl)
>>>>> +{
>>>>> + if (wait_for_completion_timeout(&evtchnl->u.req.completion,
>>>>> + msecs_to_jiffies(VSND_WAIT_BACK_MS)) <= 0)
>>>>> + return -ETIMEDOUT;
>>>>> +
>>>>> + return evtchnl->u.req.resp_status;
>>>>> +}
>>>>> +
>>>>> +int xen_snd_front_stream_query_hw_param(struct
>>>>> xen_snd_front_evtchnl *evtchnl,
>>>>> + struct xensnd_query_hw_param *hw_param_req,
>>>>> + struct xensnd_query_hw_param *hw_param_resp)
>>>>> +{
>>>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>>>> + struct xensnd_req *req;
>>>>> + unsigned long flags;
>>>>> + int ret;
>>>>> +
>>>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>>>> +
>>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_HW_PARAM_QUERY);
>>>>> + req->op.hw_param = *hw_param_req;
>>>>> +
>>>>> + ret = be_stream_do_io(evtchnl);
>>>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>>>> +
>>>>> + if (ret == 0)
>>>>> + ret = be_stream_wait_io(evtchnl);
>>>>> +
>>>>> + if (ret == 0)
>>>>> + *hw_param_resp = evtchnl->u.req.resp.hw_param;
>>>>> +
>>>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>>>> + return ret;
>>>>> +}
>>>>> +
>>>>> +int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl
>>>>> *evtchnl,
>>>>> + struct xen_snd_front_shbuf *sh_buf,
>>>>> + u8 format, unsigned int channels,
>>>>> + unsigned int rate, u32 buffer_sz,
>>>>> + u32 period_sz)
>>>>> +{
>>>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>>>> + struct xensnd_req *req;
>>>>> + unsigned long flags;
>>>>> + int ret;
>>>>> +
>>>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>>>> +
>>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_OPEN);
>>>>> + req->op.open.pcm_format = format;
>>>>> + req->op.open.pcm_channels = channels;
>>>>> + req->op.open.pcm_rate = rate;
>>>>> + req->op.open.buffer_sz = buffer_sz;
>>>>> + req->op.open.period_sz = period_sz;
>>>>> + req->op.open.gref_directory =
>>>>> xen_snd_front_shbuf_get_dir_start(sh_buf);
>>>>> +
>>>>> + ret = be_stream_do_io(evtchnl);
>>>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>>>> +
>>>>> + if (ret == 0)
>>>>> + ret = be_stream_wait_io(evtchnl);
>>>>> +
>>>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>>>> + return ret;
>>>>> +}
>>>>> +
>>>>> +int xen_snd_front_stream_close(struct xen_snd_front_evtchnl *evtchnl)
>>>>> +{
>>>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>>>> + struct xensnd_req *req;
>>>>> + unsigned long flags;
>>>>> + int ret;
>>>>> +
>>>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>>>> +
>>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_CLOSE);
>>>>> +
>>>>> + ret = be_stream_do_io(evtchnl);
>>>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>>>> +
>>>>> + if (ret == 0)
>>>>> + ret = be_stream_wait_io(evtchnl);
>>>>> +
>>>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>>>> + return ret;
>>>>> +}
>>>>> +
>>>>> +int xen_snd_front_stream_write(struct xen_snd_front_evtchnl *evtchnl,
>>>>> + unsigned long pos, unsigned long count)
>>>>> +{
>>>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>>>> + struct xensnd_req *req;
>>>>> + unsigned long flags;
>>>>> + int ret;
>>>>> +
>>>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>>>> +
>>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_WRITE);
>>>>> + req->op.rw.length = count;
>>>>> + req->op.rw.offset = pos;
>>>>> +
>>>>> + ret = be_stream_do_io(evtchnl);
>>>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>>>> +
>>>>> + if (ret == 0)
>>>>> + ret = be_stream_wait_io(evtchnl);
>>>>> +
>>>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>>>> + return ret;
>>>>> +}
>>>>> +
>>>>> +int xen_snd_front_stream_read(struct xen_snd_front_evtchnl *evtchnl,
>>>>> + unsigned long pos, unsigned long count)
>>>>> +{
>>>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>>>> + struct xensnd_req *req;
>>>>> + unsigned long flags;
>>>>> + int ret;
>>>>> +
>>>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>>>> +
>>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_READ);
>>>>> + req->op.rw.length = count;
>>>>> + req->op.rw.offset = pos;
>>>>> +
>>>>> + ret = be_stream_do_io(evtchnl);
>>>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>>>> +
>>>>> + if (ret == 0)
>>>>> + ret = be_stream_wait_io(evtchnl);
>>>>> +
>>>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>>>> + return ret;
>>>>> +}
>>>>> +
>>>>> +int xen_snd_front_stream_trigger(struct xen_snd_front_evtchnl
>>>>> *evtchnl,
>>>>> + int type)
>>>>> +{
>>>>> + struct xen_snd_front_info *front_info = evtchnl->front_info;
>>>>> + struct xensnd_req *req;
>>>>> + unsigned long flags;
>>>>> + int ret;
>>>>> +
>>>>> + mutex_lock(&evtchnl->u.req.req_io_lock);
>>>>> +
>>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>>> + req = be_stream_prepare_req(evtchnl, XENSND_OP_TRIGGER);
>>>>> + req->op.trigger.type = type;
>>>>> +
>>>>> + ret = be_stream_do_io(evtchnl);
>>>>> + spin_unlock_irqrestore(&front_info->io_lock, flags);
>>>>> +
>>>>> + if (ret == 0)
>>>>> + ret = be_stream_wait_io(evtchnl);
>>>>> +
>>>>> + mutex_unlock(&evtchnl->u.req.req_io_lock);
>>>>> + return ret;
>>>>> +}
>>>>> static void xen_snd_drv_fini(struct xen_snd_front_info *front_info)
>>>>> {
>>>>> + xen_snd_front_alsa_fini(front_info);
>>>>> xen_snd_front_evtchnl_free_all(front_info);
>>>>> }
>>>>> @@ -45,7 +236,7 @@ static int sndback_initwait(struct
>>>>> xen_snd_front_info *front_info)
>>>>> static int sndback_connect(struct xen_snd_front_info *front_info)
>>>>> {
>>>>> - return 0;
>>>>> + return xen_snd_front_alsa_init(front_info);
>>>>> }
>>>>> static void sndback_disconnect(struct xen_snd_front_info
>>>>> *front_info)
>>>>> diff --git a/sound/xen/xen_snd_front.h b/sound/xen/xen_snd_front.h
>>>>> index 9c2ffbb4e4b8..7adbdb4d2019 100644
>>>>> --- a/sound/xen/xen_snd_front.h
>>>>> +++ b/sound/xen/xen_snd_front.h
>>>>> @@ -13,17 +13,45 @@
>>>>> #include "xen_snd_front_cfg.h"
>>>>> +struct card_info;
>>>>> +struct xen_snd_front_evtchnl;
>>>>> struct xen_snd_front_evtchnl_pair;
>>>>> +struct xen_snd_front_shbuf;
>>>>> +struct xensnd_query_hw_param;
>>>>> struct xen_snd_front_info {
>>>>> struct xenbus_device *xb_dev;
>>>>> + struct card_info *card_info;
>>>>> +
>>>>> /* serializer for backend IO: request/response */
>>>>> spinlock_t io_lock;
>>>>> +
>>>>> int num_evt_pairs;
>>>>> struct xen_snd_front_evtchnl_pair *evt_pairs;
>>>>> struct xen_front_cfg_card cfg;
>>>>> };
>>>>> +int xen_snd_front_stream_query_hw_param(struct
>>>>> xen_snd_front_evtchnl *evtchnl,
>>>>> + struct xensnd_query_hw_param *hw_param_req,
>>>>> + struct xensnd_query_hw_param *hw_param_resp);
>>>>> +
>>>>> +int xen_snd_front_stream_prepare(struct xen_snd_front_evtchnl
>>>>> *evtchnl,
>>>>> + struct xen_snd_front_shbuf *sh_buf,
>>>>> + u8 format, unsigned int channels,
>>>>> + unsigned int rate, u32 buffer_sz,
>>>>> + u32 period_sz);
>>>>> +
>>>>> +int xen_snd_front_stream_close(struct xen_snd_front_evtchnl *evtchnl);
>>>>> +
>>>>> +int xen_snd_front_stream_write(struct xen_snd_front_evtchnl *evtchnl,
>>>>> + unsigned long pos, unsigned long count);
>>>>> +
>>>>> +int xen_snd_front_stream_read(struct xen_snd_front_evtchnl *evtchnl,
>>>>> + unsigned long pos, unsigned long count);
>>>>> +
>>>>> +int xen_snd_front_stream_trigger(struct xen_snd_front_evtchnl
>>>>> *evtchnl,
>>>>> + int type);
>>>>> +
>>>>> #endif /* __XEN_SND_FRONT_H */
>>>>> diff --git a/sound/xen/xen_snd_front_alsa.c
>>>>> b/sound/xen/xen_snd_front_alsa.c
>>>>> new file mode 100644
>>>>> index 000000000000..f524b172750e
>>>>> --- /dev/null
>>>>> +++ b/sound/xen/xen_snd_front_alsa.c
>>>>> @@ -0,0 +1,830 @@
>>>>> +// SPDX-License-Identifier: GPL-2.0 OR MIT
>>>>> +
>>>>> +/*
>>>>> + * Xen para-virtual sound device
>>>>> + *
>>>>> + * Copyright (C) 2016-2018 EPAM Systems Inc.
>>>>> + *
>>>>> + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>>>> + */
>>>>> +
>>>>> +#include <linux/platform_device.h>
>>>>> +
>>>>> +#include <sound/core.h>
>>>>> +#include <sound/pcm.h>
>>>>> +#include <sound/pcm_params.h>
>>>>> +
>>>>> +#include <xen/xenbus.h>
>>>>> +
>>>>> +#include "xen_snd_front.h"
>>>>> +#include "xen_snd_front_alsa.h"
>>>>> +#include "xen_snd_front_cfg.h"
>>>>> +#include "xen_snd_front_evtchnl.h"
>>>>> +#include "xen_snd_front_shbuf.h"
>>>>> +
>>>>> +struct pcm_stream_info {
>>>> Not sure how this is generally handled in the sound drivers, but when
>>>> reviewing the code using those structures I repeatedly tried to find
>>>> their definitions in the sound headers instead of here. Same applies to
>>>> the alsa_* names.
>>>>
>>>> I'd prefer names which don't poison the name space.
>>> I'll try to do something about naming
>> One question still remains wrt alsa_* names: if this is for structures
>> I have (alsa_sndif_sample_format/alsa_sndif_hw_param), then
>> those already have sndif in their name which clearly says these are
>> Xen related ones (sndif is a Xen protocol).
>> If you also don't like the alsa_* function names then those are all
>> static and defined in this same file, so see no confusion here.
>>
>> I have changed other non-obvious struct names:
>>
>> -struct pcm_stream_info {
>> +struct xen_snd_front_pcm_stream_info {
>>
>> -struct pcm_instance_info {
>> +struct xen_snd_front_pcm_instance_info {
>>
>> -struct card_info {
>> +struct xen_snd_front_card_info {
>>
>> Does the above work for you?
> Yes, this seems to be okay.
Good, thank you
> Thanks,
>
> Juergen
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver
2018-04-16 6:24 [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver Oleksandr Andrushchenko
` (4 preceding siblings ...)
2018-04-16 6:24 ` [PATCH v2 5/5] ALSA: xen-front: Implement ALSA virtual sound driver Oleksandr Andrushchenko
@ 2018-04-17 12:42 ` Oleksandr Andrushchenko
2018-04-18 15:15 ` Oleksandr Andrushchenko
2018-05-02 7:59 ` Oleksandr Andrushchenko
7 siblings, 0 replies; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-17 12:42 UTC (permalink / raw)
To: xen-devel, linux-kernel, alsa-devel, jgross, boris.ostrovsky,
konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
Hello, Juergen!
Thank you very much for reviewing the driver and providing
valuable comments! I will send v3 of the driver once I have
more reviews, especially I hope ALSA community can also take a look
Also, as you suggested on IRC, I will add a patch for adding
myself as sound/xen maintainer.
Thank you,
Oleksandr
On 04/16/2018 09:24 AM, Oleksandr Andrushchenko wrote:
> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>
> Please note: this patch series depends on [3].
>
> This patch series adds support for Xen [1] para-virtualized
> sound frontend driver. It implements the protocol from
> include/xen/interface/io/sndif.h with the following limitations:
> - mute/unmute is not supported
> - get/set volume is not supported
> Volume control is not supported for the reason that most of the
> use-cases (at the moment) are based on scenarious where
> unprivileged OS (e.g. Android, AGL etc) use software mixers.
>
> Both capture and playback are supported.
>
> Corresponding backend, implemented as a user-space application, can be
> found at [2].
>
> Thank you,
> Oleksandr
>
> Changes since v1:
> *****************
>
> 1. Moved driver from sound/drivers to sound/xen
>
> 2. Coding style changes to better meet Linux Kernel
>
> 3. Added explicit back and front synchronization
> In order to provide explicit synchronization between backend and
> frontend the following changes are introduced in the protocol:
> - add new ring buffer for sending asynchronous events from
> backend to frontend to report number of bytes played by the
> frontend (XENSND_EVT_CUR_POS)
> - introduce trigger events for playback control: start/stop/pause/resume
> - add "req-" prefix to event-channel and ring-ref to unify naming
> of the Xen event channels for requests and events
>
> 4. Added explicit back and front parameter negotiation
> In order to provide explicit stream parameter negotiation between
> backend and frontend the following changes are introduced in the protocol:
> add XENSND_OP_HW_PARAM_QUERY request to read/update
> configuration space for the parameters given: request passes
> desired parameter's intervals/masks and the response to this request
> returns allowed min/max intervals/masks to be used.
>
> [1] https://xenproject.org/
> [2] https://github.com/xen-troops/snd_be
> [3] https://lkml.org/lkml/2018/4/12/522
>
> Oleksandr Andrushchenko (5):
> ALSA: xen-front: Introduce Xen para-virtualized sound frontend driver
> ALSA: xen-front: Read sound driver configuration from Xen store
> ALSA: xen-front: Implement Xen event channel handling
> ALSA: xen-front: Implement handling of shared buffers
> ALSA: xen-front: Implement ALSA virtual sound driver
>
> sound/Kconfig | 2 +
> sound/Makefile | 2 +-
> sound/xen/Kconfig | 10 +
> sound/xen/Makefile | 9 +
> sound/xen/xen_snd_front.c | 410 +++++++++++++++++++
> sound/xen/xen_snd_front.h | 57 +++
> sound/xen/xen_snd_front_alsa.c | 830 ++++++++++++++++++++++++++++++++++++++
> sound/xen/xen_snd_front_alsa.h | 23 ++
> sound/xen/xen_snd_front_cfg.c | 517 ++++++++++++++++++++++++
> sound/xen/xen_snd_front_cfg.h | 46 +++
> sound/xen/xen_snd_front_evtchnl.c | 478 ++++++++++++++++++++++
> sound/xen/xen_snd_front_evtchnl.h | 92 +++++
> sound/xen/xen_snd_front_shbuf.c | 193 +++++++++
> sound/xen/xen_snd_front_shbuf.h | 36 ++
> 14 files changed, 2704 insertions(+), 1 deletion(-)
> create mode 100644 sound/xen/Kconfig
> create mode 100644 sound/xen/Makefile
> create mode 100644 sound/xen/xen_snd_front.c
> create mode 100644 sound/xen/xen_snd_front.h
> create mode 100644 sound/xen/xen_snd_front_alsa.c
> create mode 100644 sound/xen/xen_snd_front_alsa.h
> create mode 100644 sound/xen/xen_snd_front_cfg.c
> create mode 100644 sound/xen/xen_snd_front_cfg.h
> create mode 100644 sound/xen/xen_snd_front_evtchnl.c
> create mode 100644 sound/xen/xen_snd_front_evtchnl.h
> create mode 100644 sound/xen/xen_snd_front_shbuf.c
> create mode 100644 sound/xen/xen_snd_front_shbuf.h
>
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver
2018-04-16 6:24 [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver Oleksandr Andrushchenko
` (5 preceding siblings ...)
2018-04-17 12:42 ` [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver Oleksandr Andrushchenko
@ 2018-04-18 15:15 ` Oleksandr Andrushchenko
2018-04-23 6:34 ` Oleksandr Andrushchenko
2018-05-02 7:59 ` Oleksandr Andrushchenko
7 siblings, 1 reply; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-18 15:15 UTC (permalink / raw)
To: xen-devel, linux-kernel, alsa-devel, jgross, boris.ostrovsky,
konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 04/16/2018 09:24 AM, Oleksandr Andrushchenko wrote:
> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>
> Please note: this patch series depends on [3].
The dependency is now merged into Xen kernel tree [4] for-linus-4.17
>
> This patch series adds support for Xen [1] para-virtualized
> sound frontend driver. It implements the protocol from
> include/xen/interface/io/sndif.h with the following limitations:
> - mute/unmute is not supported
> - get/set volume is not supported
> Volume control is not supported for the reason that most of the
> use-cases (at the moment) are based on scenarious where
> unprivileged OS (e.g. Android, AGL etc) use software mixers.
>
> Both capture and playback are supported.
>
> Corresponding backend, implemented as a user-space application, can be
> found at [2].
>
> Thank you,
> Oleksandr
>
> Changes since v1:
> *****************
>
> 1. Moved driver from sound/drivers to sound/xen
>
> 2. Coding style changes to better meet Linux Kernel
>
> 3. Added explicit back and front synchronization
> In order to provide explicit synchronization between backend and
> frontend the following changes are introduced in the protocol:
> - add new ring buffer for sending asynchronous events from
> backend to frontend to report number of bytes played by the
> frontend (XENSND_EVT_CUR_POS)
> - introduce trigger events for playback control: start/stop/pause/resume
> - add "req-" prefix to event-channel and ring-ref to unify naming
> of the Xen event channels for requests and events
>
> 4. Added explicit back and front parameter negotiation
> In order to provide explicit stream parameter negotiation between
> backend and frontend the following changes are introduced in the protocol:
> add XENSND_OP_HW_PARAM_QUERY request to read/update
> configuration space for the parameters given: request passes
> desired parameter's intervals/masks and the response to this request
> returns allowed min/max intervals/masks to be used.
>
> [1] https://xenproject.org/
> [2] https://github.com/xen-troops/snd_be
> [3] https://lkml.org/lkml/2018/4/12/522
>
> Oleksandr Andrushchenko (5):
> ALSA: xen-front: Introduce Xen para-virtualized sound frontend driver
> ALSA: xen-front: Read sound driver configuration from Xen store
> ALSA: xen-front: Implement Xen event channel handling
> ALSA: xen-front: Implement handling of shared buffers
> ALSA: xen-front: Implement ALSA virtual sound driver
>
> sound/Kconfig | 2 +
> sound/Makefile | 2 +-
> sound/xen/Kconfig | 10 +
> sound/xen/Makefile | 9 +
> sound/xen/xen_snd_front.c | 410 +++++++++++++++++++
> sound/xen/xen_snd_front.h | 57 +++
> sound/xen/xen_snd_front_alsa.c | 830 ++++++++++++++++++++++++++++++++++++++
> sound/xen/xen_snd_front_alsa.h | 23 ++
> sound/xen/xen_snd_front_cfg.c | 517 ++++++++++++++++++++++++
> sound/xen/xen_snd_front_cfg.h | 46 +++
> sound/xen/xen_snd_front_evtchnl.c | 478 ++++++++++++++++++++++
> sound/xen/xen_snd_front_evtchnl.h | 92 +++++
> sound/xen/xen_snd_front_shbuf.c | 193 +++++++++
> sound/xen/xen_snd_front_shbuf.h | 36 ++
> 14 files changed, 2704 insertions(+), 1 deletion(-)
> create mode 100644 sound/xen/Kconfig
> create mode 100644 sound/xen/Makefile
> create mode 100644 sound/xen/xen_snd_front.c
> create mode 100644 sound/xen/xen_snd_front.h
> create mode 100644 sound/xen/xen_snd_front_alsa.c
> create mode 100644 sound/xen/xen_snd_front_alsa.h
> create mode 100644 sound/xen/xen_snd_front_cfg.c
> create mode 100644 sound/xen/xen_snd_front_cfg.h
> create mode 100644 sound/xen/xen_snd_front_evtchnl.c
> create mode 100644 sound/xen/xen_snd_front_evtchnl.h
> create mode 100644 sound/xen/xen_snd_front_shbuf.c
> create mode 100644 sound/xen/xen_snd_front_shbuf.h
>
[4]
https://git.kernel.org/pub/scm/linux/kernel/git/xen/tip.git/commit/?h=for-linus-4.17&id=cd6e992b3aab072cc90839508aaf5573c8f7e066
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver
2018-04-18 15:15 ` Oleksandr Andrushchenko
@ 2018-04-23 6:34 ` Oleksandr Andrushchenko
0 siblings, 0 replies; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-23 6:34 UTC (permalink / raw)
To: xen-devel, linux-kernel, alsa-devel, jgross, boris.ostrovsky,
konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
On 04/18/2018 06:15 PM, Oleksandr Andrushchenko wrote:
> On 04/16/2018 09:24 AM, Oleksandr Andrushchenko wrote:
>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>>
>> Please note: this patch series depends on [3].
> The dependency is now merged into Xen kernel tree [4] for-linus-4.17
The dependency is now pulled into Linus tree [5]
>>
>> This patch series adds support for Xen [1] para-virtualized
>> sound frontend driver. It implements the protocol from
>> include/xen/interface/io/sndif.h with the following limitations:
>> - mute/unmute is not supported
>> - get/set volume is not supported
>> Volume control is not supported for the reason that most of the
>> use-cases (at the moment) are based on scenarious where
>> unprivileged OS (e.g. Android, AGL etc) use software mixers.
>>
>> Both capture and playback are supported.
>>
>> Corresponding backend, implemented as a user-space application, can be
>> found at [2].
>>
>> Thank you,
>> Oleksandr
>>
>> Changes since v1:
>> *****************
>>
>> 1. Moved driver from sound/drivers to sound/xen
>>
>> 2. Coding style changes to better meet Linux Kernel
>>
>> 3. Added explicit back and front synchronization
>> In order to provide explicit synchronization between backend and
>> frontend the following changes are introduced in the protocol:
>> - add new ring buffer for sending asynchronous events from
>> backend to frontend to report number of bytes played by the
>> frontend (XENSND_EVT_CUR_POS)
>> - introduce trigger events for playback control:
>> start/stop/pause/resume
>> - add "req-" prefix to event-channel and ring-ref to unify naming
>> of the Xen event channels for requests and events
>>
>> 4. Added explicit back and front parameter negotiation
>> In order to provide explicit stream parameter negotiation between
>> backend and frontend the following changes are introduced in the
>> protocol:
>> add XENSND_OP_HW_PARAM_QUERY request to read/update
>> configuration space for the parameters given: request passes
>> desired parameter's intervals/masks and the response to this request
>> returns allowed min/max intervals/masks to be used.
>>
>> [1] https://xenproject.org/
>> [2] https://github.com/xen-troops/snd_be
>> [3] https://lkml.org/lkml/2018/4/12/522
>>
>> Oleksandr Andrushchenko (5):
>> ALSA: xen-front: Introduce Xen para-virtualized sound frontend driver
>> ALSA: xen-front: Read sound driver configuration from Xen store
>> ALSA: xen-front: Implement Xen event channel handling
>> ALSA: xen-front: Implement handling of shared buffers
>> ALSA: xen-front: Implement ALSA virtual sound driver
>>
>> sound/Kconfig | 2 +
>> sound/Makefile | 2 +-
>> sound/xen/Kconfig | 10 +
>> sound/xen/Makefile | 9 +
>> sound/xen/xen_snd_front.c | 410 +++++++++++++++++++
>> sound/xen/xen_snd_front.h | 57 +++
>> sound/xen/xen_snd_front_alsa.c | 830
>> ++++++++++++++++++++++++++++++++++++++
>> sound/xen/xen_snd_front_alsa.h | 23 ++
>> sound/xen/xen_snd_front_cfg.c | 517 ++++++++++++++++++++++++
>> sound/xen/xen_snd_front_cfg.h | 46 +++
>> sound/xen/xen_snd_front_evtchnl.c | 478 ++++++++++++++++++++++
>> sound/xen/xen_snd_front_evtchnl.h | 92 +++++
>> sound/xen/xen_snd_front_shbuf.c | 193 +++++++++
>> sound/xen/xen_snd_front_shbuf.h | 36 ++
>> 14 files changed, 2704 insertions(+), 1 deletion(-)
>> create mode 100644 sound/xen/Kconfig
>> create mode 100644 sound/xen/Makefile
>> create mode 100644 sound/xen/xen_snd_front.c
>> create mode 100644 sound/xen/xen_snd_front.h
>> create mode 100644 sound/xen/xen_snd_front_alsa.c
>> create mode 100644 sound/xen/xen_snd_front_alsa.h
>> create mode 100644 sound/xen/xen_snd_front_cfg.c
>> create mode 100644 sound/xen/xen_snd_front_cfg.h
>> create mode 100644 sound/xen/xen_snd_front_evtchnl.c
>> create mode 100644 sound/xen/xen_snd_front_evtchnl.h
>> create mode 100644 sound/xen/xen_snd_front_shbuf.c
>> create mode 100644 sound/xen/xen_snd_front_shbuf.h
>>
> [4]
> https://git.kernel.org/pub/scm/linux/kernel/git/xen/tip.git/commit/?h=for-linus-4.17&id=cd6e992b3aab072cc90839508aaf5573c8f7e066
[5]
https://elixir.bootlin.com/linux/v4.17-rc2/source/include/xen/interface/io/sndif.h
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 1/5] ALSA: xen-front: Introduce Xen para-virtualized sound frontend driver
2018-04-16 6:24 ` [PATCH v2 1/5] ALSA: xen-front: Introduce Xen para-virtualized sound " Oleksandr Andrushchenko
2018-04-16 12:25 ` Juergen Gross
@ 2018-04-24 13:55 ` Takashi Iwai
2018-04-24 13:59 ` Oleksandr Andrushchenko
1 sibling, 1 reply; 40+ messages in thread
From: Takashi Iwai @ 2018-04-24 13:55 UTC (permalink / raw)
To: Oleksandr Andrushchenko
Cc: alsa-devel, xen-devel, boris.ostrovsky, konrad.wilk, perex,
Juergen Gross, linux-kernel, Oleksandr Andrushchenko
On Mon, 16 Apr 2018 08:24:49 +0200,
Oleksandr Andrushchenko wrote:
> --- /dev/null
> +++ b/sound/xen/Kconfig
> @@ -0,0 +1,10 @@
> +# ALSA Xen drivers
> +
> +config SND_XEN_FRONTEND
> + tristate "Xen para-virtualized sound frontend driver"
> + depends on XEN && SND_PCM
Please do select SND_PCM instead of depends.
> + select XEN_XENBUS_FRONTEND
> + default n
"default n" is superfluous, drop it.
thanks,
Takashi
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 1/5] ALSA: xen-front: Introduce Xen para-virtualized sound frontend driver
2018-04-24 13:55 ` Takashi Iwai
@ 2018-04-24 13:59 ` Oleksandr Andrushchenko
0 siblings, 0 replies; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-24 13:59 UTC (permalink / raw)
To: Takashi Iwai
Cc: alsa-devel, xen-devel, boris.ostrovsky, konrad.wilk, perex,
Juergen Gross, linux-kernel, Oleksandr Andrushchenko
On 04/24/2018 04:55 PM, Takashi Iwai wrote:
> On Mon, 16 Apr 2018 08:24:49 +0200,
> Oleksandr Andrushchenko wrote:
>> --- /dev/null
>> +++ b/sound/xen/Kconfig
>> @@ -0,0 +1,10 @@
>> +# ALSA Xen drivers
>> +
>> +config SND_XEN_FRONTEND
>> + tristate "Xen para-virtualized sound frontend driver"
>> + depends on XEN && SND_PCM
> Please do select SND_PCM instead of depends.
will do
>> + select XEN_XENBUS_FRONTEND
>> + default n
> "default n" is superfluous, drop it.
will drop
>
> thanks,
>
> Takashi
Thank you,
Oleksandr
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling
2018-04-16 6:24 ` [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling Oleksandr Andrushchenko
2018-04-16 13:12 ` Juergen Gross
2018-04-16 13:53 ` kbuild test robot
@ 2018-04-24 14:20 ` Takashi Iwai
2018-04-24 14:29 ` Oleksandr Andrushchenko
2 siblings, 1 reply; 40+ messages in thread
From: Takashi Iwai @ 2018-04-24 14:20 UTC (permalink / raw)
To: Oleksandr Andrushchenko
Cc: alsa-devel, xen-devel, boris.ostrovsky, konrad.wilk, perex,
Juergen Gross, linux-kernel, Oleksandr Andrushchenko
On Mon, 16 Apr 2018 08:24:51 +0200,
Oleksandr Andrushchenko wrote:
> +static irqreturn_t evtchnl_interrupt_req(int irq, void *dev_id)
> +{
> + struct xen_snd_front_evtchnl *channel = dev_id;
> + struct xen_snd_front_info *front_info = channel->front_info;
> + struct xensnd_resp *resp;
> + RING_IDX i, rp;
> + unsigned long flags;
> +
> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
> + return IRQ_HANDLED;
> +
> + spin_lock_irqsave(&front_info->io_lock, flags);
> +
> +again:
> + rp = channel->u.req.ring.sring->rsp_prod;
> + /* ensure we see queued responses up to rp */
> + rmb();
> +
> + for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
I'm not familiar with Xen stuff in general, but through a quick
glance, this kind of code worries me a bit.
If channel->u.req.ring.rsp_cons has a bogus number, this may lead to a
very long loop, no? Better to have a sanity check of the ring buffer
size.
> +static irqreturn_t evtchnl_interrupt_evt(int irq, void *dev_id)
> +{
> + struct xen_snd_front_evtchnl *channel = dev_id;
> + struct xen_snd_front_info *front_info = channel->front_info;
> + struct xensnd_event_page *page = channel->u.evt.page;
> + u32 cons, prod;
> + unsigned long flags;
> +
> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
> + return IRQ_HANDLED;
> +
> + spin_lock_irqsave(&front_info->io_lock, flags);
> +
> + prod = page->in_prod;
> + /* ensure we see ring contents up to prod */
> + virt_rmb();
> + if (prod == page->in_cons)
> + goto out;
> +
> + for (cons = page->in_cons; cons != prod; cons++) {
Ditto.
thanks,
Takashi
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling
2018-04-24 14:20 ` Takashi Iwai
@ 2018-04-24 14:29 ` Oleksandr Andrushchenko
2018-04-24 14:35 ` Takashi Iwai
0 siblings, 1 reply; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-24 14:29 UTC (permalink / raw)
To: Takashi Iwai
Cc: alsa-devel, xen-devel, boris.ostrovsky, konrad.wilk, perex,
Juergen Gross, linux-kernel, Oleksandr Andrushchenko
On 04/24/2018 05:20 PM, Takashi Iwai wrote:
> On Mon, 16 Apr 2018 08:24:51 +0200,
> Oleksandr Andrushchenko wrote:
>> +static irqreturn_t evtchnl_interrupt_req(int irq, void *dev_id)
>> +{
>> + struct xen_snd_front_evtchnl *channel = dev_id;
>> + struct xen_snd_front_info *front_info = channel->front_info;
>> + struct xensnd_resp *resp;
>> + RING_IDX i, rp;
>> + unsigned long flags;
>> +
>> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
>> + return IRQ_HANDLED;
>> +
>> + spin_lock_irqsave(&front_info->io_lock, flags);
>> +
>> +again:
>> + rp = channel->u.req.ring.sring->rsp_prod;
>> + /* ensure we see queued responses up to rp */
>> + rmb();
>> +
>> + for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
> I'm not familiar with Xen stuff in general, but through a quick
> glance, this kind of code worries me a bit.
>
> If channel->u.req.ring.rsp_cons has a bogus number, this may lead to a
> very long loop, no? Better to have a sanity check of the ring buffer
> size.
In this loop I have:
resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
and the RING_GET_RESPONSE macro is designed in the way that
it wraps around when *i* in the question gets bigger than
the ring size:
#define RING_GET_REQUEST(_r, _idx) \
(&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
So, even if the counter has a bogus number it will not last long
>> +static irqreturn_t evtchnl_interrupt_evt(int irq, void *dev_id)
>> +{
>> + struct xen_snd_front_evtchnl *channel = dev_id;
>> + struct xen_snd_front_info *front_info = channel->front_info;
>> + struct xensnd_event_page *page = channel->u.evt.page;
>> + u32 cons, prod;
>> + unsigned long flags;
>> +
>> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
>> + return IRQ_HANDLED;
>> +
>> + spin_lock_irqsave(&front_info->io_lock, flags);
>> +
>> + prod = page->in_prod;
>> + /* ensure we see ring contents up to prod */
>> + virt_rmb();
>> + if (prod == page->in_cons)
>> + goto out;
>> +
>> + for (cons = page->in_cons; cons != prod; cons++) {
> Ditto.
Same as above
>
> thanks,
>
> Takashi
Thank you,
Oleksandr
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling
2018-04-24 14:29 ` Oleksandr Andrushchenko
@ 2018-04-24 14:35 ` Takashi Iwai
2018-04-24 14:58 ` Oleksandr Andrushchenko
0 siblings, 1 reply; 40+ messages in thread
From: Takashi Iwai @ 2018-04-24 14:35 UTC (permalink / raw)
To: Oleksandr Andrushchenko
Cc: alsa-devel, xen-devel, boris.ostrovsky, konrad.wilk, perex,
Juergen Gross, linux-kernel, Oleksandr Andrushchenko
On Tue, 24 Apr 2018 16:29:15 +0200,
Oleksandr Andrushchenko wrote:
>
> On 04/24/2018 05:20 PM, Takashi Iwai wrote:
> > On Mon, 16 Apr 2018 08:24:51 +0200,
> > Oleksandr Andrushchenko wrote:
> >> +static irqreturn_t evtchnl_interrupt_req(int irq, void *dev_id)
> >> +{
> >> + struct xen_snd_front_evtchnl *channel = dev_id;
> >> + struct xen_snd_front_info *front_info = channel->front_info;
> >> + struct xensnd_resp *resp;
> >> + RING_IDX i, rp;
> >> + unsigned long flags;
> >> +
> >> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
> >> + return IRQ_HANDLED;
> >> +
> >> + spin_lock_irqsave(&front_info->io_lock, flags);
> >> +
> >> +again:
> >> + rp = channel->u.req.ring.sring->rsp_prod;
> >> + /* ensure we see queued responses up to rp */
> >> + rmb();
> >> +
> >> + for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
> > I'm not familiar with Xen stuff in general, but through a quick
> > glance, this kind of code worries me a bit.
> >
> > If channel->u.req.ring.rsp_cons has a bogus number, this may lead to a
> > very long loop, no? Better to have a sanity check of the ring buffer
> > size.
> In this loop I have:
> resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
> and the RING_GET_RESPONSE macro is designed in the way that
> it wraps around when *i* in the question gets bigger than
> the ring size:
>
> #define RING_GET_REQUEST(_r, _idx) \
> (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
>
> So, even if the counter has a bogus number it will not last long
Hm, this prevents from accessing outside the ring buffer, but does it
change the loop behavior?
Suppose channel->u.req.ring_rsp_cons = 1, and rp = 0, the loop below
would still consume the whole 32bit counts, no?
for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
...
}
Takashi
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling
2018-04-24 14:35 ` Takashi Iwai
@ 2018-04-24 14:58 ` Oleksandr Andrushchenko
2018-04-24 15:02 ` Takashi Iwai
0 siblings, 1 reply; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-24 14:58 UTC (permalink / raw)
To: Takashi Iwai
Cc: alsa-devel, xen-devel, boris.ostrovsky, konrad.wilk, perex,
Juergen Gross, linux-kernel, Oleksandr Andrushchenko
On 04/24/2018 05:35 PM, Takashi Iwai wrote:
> On Tue, 24 Apr 2018 16:29:15 +0200,
> Oleksandr Andrushchenko wrote:
>> On 04/24/2018 05:20 PM, Takashi Iwai wrote:
>>> On Mon, 16 Apr 2018 08:24:51 +0200,
>>> Oleksandr Andrushchenko wrote:
>>>> +static irqreturn_t evtchnl_interrupt_req(int irq, void *dev_id)
>>>> +{
>>>> + struct xen_snd_front_evtchnl *channel = dev_id;
>>>> + struct xen_snd_front_info *front_info = channel->front_info;
>>>> + struct xensnd_resp *resp;
>>>> + RING_IDX i, rp;
>>>> + unsigned long flags;
>>>> +
>>>> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
>>>> + return IRQ_HANDLED;
>>>> +
>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>> +
>>>> +again:
>>>> + rp = channel->u.req.ring.sring->rsp_prod;
>>>> + /* ensure we see queued responses up to rp */
>>>> + rmb();
>>>> +
>>>> + for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
>>> I'm not familiar with Xen stuff in general, but through a quick
>>> glance, this kind of code worries me a bit.
>>>
>>> If channel->u.req.ring.rsp_cons has a bogus number, this may lead to a
>>> very long loop, no? Better to have a sanity check of the ring buffer
>>> size.
>> In this loop I have:
>> resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
>> and the RING_GET_RESPONSE macro is designed in the way that
>> it wraps around when *i* in the question gets bigger than
>> the ring size:
>>
>> #define RING_GET_REQUEST(_r, _idx) \
>> (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
>>
>> So, even if the counter has a bogus number it will not last long
> Hm, this prevents from accessing outside the ring buffer, but does it
> change the loop behavior?
no, it doesn't
> Suppose channel->u.req.ring_rsp_cons = 1, and rp = 0, the loop below
> would still consume the whole 32bit counts, no?
>
> for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
> resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
> ...
> }
You are right here and the comment is totally valid.
I'll put an additional check like here [1] and here [2]
Will this address your comment?
>
> Takashi
Thank you,
Oleksandr
[1]
https://elixir.bootlin.com/linux/v4.17-rc2/source/drivers/block/xen-blkback/blkback.c#L1127
[2]
https://elixir.bootlin.com/linux/v4.17-rc2/source/drivers/block/xen-blkback/blkback.c#L1135
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling
2018-04-24 14:58 ` Oleksandr Andrushchenko
@ 2018-04-24 15:02 ` Takashi Iwai
2018-04-24 16:23 ` Oleksandr Andrushchenko
0 siblings, 1 reply; 40+ messages in thread
From: Takashi Iwai @ 2018-04-24 15:02 UTC (permalink / raw)
To: Oleksandr Andrushchenko
Cc: alsa-devel, xen-devel, boris.ostrovsky, konrad.wilk, perex,
Juergen Gross, linux-kernel, Oleksandr Andrushchenko
On Tue, 24 Apr 2018 16:58:43 +0200,
Oleksandr Andrushchenko wrote:
>
> On 04/24/2018 05:35 PM, Takashi Iwai wrote:
> > On Tue, 24 Apr 2018 16:29:15 +0200,
> > Oleksandr Andrushchenko wrote:
> >> On 04/24/2018 05:20 PM, Takashi Iwai wrote:
> >>> On Mon, 16 Apr 2018 08:24:51 +0200,
> >>> Oleksandr Andrushchenko wrote:
> >>>> +static irqreturn_t evtchnl_interrupt_req(int irq, void *dev_id)
> >>>> +{
> >>>> + struct xen_snd_front_evtchnl *channel = dev_id;
> >>>> + struct xen_snd_front_info *front_info = channel->front_info;
> >>>> + struct xensnd_resp *resp;
> >>>> + RING_IDX i, rp;
> >>>> + unsigned long flags;
> >>>> +
> >>>> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
> >>>> + return IRQ_HANDLED;
> >>>> +
> >>>> + spin_lock_irqsave(&front_info->io_lock, flags);
> >>>> +
> >>>> +again:
> >>>> + rp = channel->u.req.ring.sring->rsp_prod;
> >>>> + /* ensure we see queued responses up to rp */
> >>>> + rmb();
> >>>> +
> >>>> + for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
> >>> I'm not familiar with Xen stuff in general, but through a quick
> >>> glance, this kind of code worries me a bit.
> >>>
> >>> If channel->u.req.ring.rsp_cons has a bogus number, this may lead to a
> >>> very long loop, no? Better to have a sanity check of the ring buffer
> >>> size.
> >> In this loop I have:
> >> resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
> >> and the RING_GET_RESPONSE macro is designed in the way that
> >> it wraps around when *i* in the question gets bigger than
> >> the ring size:
> >>
> >> #define RING_GET_REQUEST(_r, _idx) \
> >> (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
> >>
> >> So, even if the counter has a bogus number it will not last long
> > Hm, this prevents from accessing outside the ring buffer, but does it
> > change the loop behavior?
> no, it doesn't
> > Suppose channel->u.req.ring_rsp_cons = 1, and rp = 0, the loop below
> > would still consume the whole 32bit counts, no?
> >
> > for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
> > resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
> > ...
> > }
> You are right here and the comment is totally valid.
> I'll put an additional check like here [1] and here [2]
> Will this address your comment?
Yep, this kind of sanity checks should work.
thanks,
Takashi
> >
> > Takashi
> Thank you,
> Oleksandr
>
> [1]
> https://elixir.bootlin.com/linux/v4.17-rc2/source/drivers/block/xen-blkback/blkback.c#L1127
> [2]
> https://elixir.bootlin.com/linux/v4.17-rc2/source/drivers/block/xen-blkback/blkback.c#L1135
>
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling
2018-04-24 15:02 ` Takashi Iwai
@ 2018-04-24 16:23 ` Oleksandr Andrushchenko
2018-04-25 8:26 ` Oleksandr Andrushchenko
0 siblings, 1 reply; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-24 16:23 UTC (permalink / raw)
To: Takashi Iwai
Cc: alsa-devel, xen-devel, boris.ostrovsky, konrad.wilk, perex,
Juergen Gross, linux-kernel, Oleksandr Andrushchenko
On 04/24/2018 06:02 PM, Takashi Iwai wrote:
> On Tue, 24 Apr 2018 16:58:43 +0200,
> Oleksandr Andrushchenko wrote:
>> On 04/24/2018 05:35 PM, Takashi Iwai wrote:
>>> On Tue, 24 Apr 2018 16:29:15 +0200,
>>> Oleksandr Andrushchenko wrote:
>>>> On 04/24/2018 05:20 PM, Takashi Iwai wrote:
>>>>> On Mon, 16 Apr 2018 08:24:51 +0200,
>>>>> Oleksandr Andrushchenko wrote:
>>>>>> +static irqreturn_t evtchnl_interrupt_req(int irq, void *dev_id)
>>>>>> +{
>>>>>> + struct xen_snd_front_evtchnl *channel = dev_id;
>>>>>> + struct xen_snd_front_info *front_info = channel->front_info;
>>>>>> + struct xensnd_resp *resp;
>>>>>> + RING_IDX i, rp;
>>>>>> + unsigned long flags;
>>>>>> +
>>>>>> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
>>>>>> + return IRQ_HANDLED;
>>>>>> +
>>>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>>>> +
>>>>>> +again:
>>>>>> + rp = channel->u.req.ring.sring->rsp_prod;
>>>>>> + /* ensure we see queued responses up to rp */
>>>>>> + rmb();
>>>>>> +
>>>>>> + for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
>>>>> I'm not familiar with Xen stuff in general, but through a quick
>>>>> glance, this kind of code worries me a bit.
>>>>>
>>>>> If channel->u.req.ring.rsp_cons has a bogus number, this may lead to a
>>>>> very long loop, no? Better to have a sanity check of the ring buffer
>>>>> size.
>>>> In this loop I have:
>>>> resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
>>>> and the RING_GET_RESPONSE macro is designed in the way that
>>>> it wraps around when *i* in the question gets bigger than
>>>> the ring size:
>>>>
>>>> #define RING_GET_REQUEST(_r, _idx) \
>>>> (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
>>>>
>>>> So, even if the counter has a bogus number it will not last long
>>> Hm, this prevents from accessing outside the ring buffer, but does it
>>> change the loop behavior?
>> no, it doesn't
>>> Suppose channel->u.req.ring_rsp_cons = 1, and rp = 0, the loop below
>>> would still consume the whole 32bit counts, no?
>>>
>>> for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
>>> resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
>>> ...
>>> }
>> You are right here and the comment is totally valid.
>> I'll put an additional check like here [1] and here [2]
>> Will this address your comment?
> Yep, this kind of sanity checks should work.
>
Great, will implement the checks this way then
> thanks,
>
> Takashi
Thank you,
Oleksandr
>>> Takashi
>> Thank you,
>> Oleksandr
>>
>> [1]
>> https://elixir.bootlin.com/linux/v4.17-rc2/source/drivers/block/xen-blkback/blkback.c#L1127
>> [2]
>> https://elixir.bootlin.com/linux/v4.17-rc2/source/drivers/block/xen-blkback/blkback.c#L1135
>>
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling
2018-04-24 16:23 ` Oleksandr Andrushchenko
@ 2018-04-25 8:26 ` Oleksandr Andrushchenko
2018-04-25 9:02 ` Takashi Iwai
0 siblings, 1 reply; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-25 8:26 UTC (permalink / raw)
To: Takashi Iwai
Cc: alsa-devel, xen-devel, boris.ostrovsky, konrad.wilk, perex,
Juergen Gross, linux-kernel, Oleksandr Andrushchenko
On 04/24/2018 07:23 PM, Oleksandr Andrushchenko wrote:
> On 04/24/2018 06:02 PM, Takashi Iwai wrote:
>> On Tue, 24 Apr 2018 16:58:43 +0200,
>> Oleksandr Andrushchenko wrote:
>>> On 04/24/2018 05:35 PM, Takashi Iwai wrote:
>>>> On Tue, 24 Apr 2018 16:29:15 +0200,
>>>> Oleksandr Andrushchenko wrote:
>>>>> On 04/24/2018 05:20 PM, Takashi Iwai wrote:
>>>>>> On Mon, 16 Apr 2018 08:24:51 +0200,
>>>>>> Oleksandr Andrushchenko wrote:
>>>>>>> +static irqreturn_t evtchnl_interrupt_req(int irq, void *dev_id)
>>>>>>> +{
>>>>>>> + struct xen_snd_front_evtchnl *channel = dev_id;
>>>>>>> + struct xen_snd_front_info *front_info = channel->front_info;
>>>>>>> + struct xensnd_resp *resp;
>>>>>>> + RING_IDX i, rp;
>>>>>>> + unsigned long flags;
>>>>>>> +
>>>>>>> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
>>>>>>> + return IRQ_HANDLED;
>>>>>>> +
>>>>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>>>>> +
>>>>>>> +again:
>>>>>>> + rp = channel->u.req.ring.sring->rsp_prod;
>>>>>>> + /* ensure we see queued responses up to rp */
>>>>>>> + rmb();
>>>>>>> +
>>>>>>> + for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
>>>>>> I'm not familiar with Xen stuff in general, but through a quick
>>>>>> glance, this kind of code worries me a bit.
>>>>>>
>>>>>> If channel->u.req.ring.rsp_cons has a bogus number, this may lead
>>>>>> to a
>>>>>> very long loop, no? Better to have a sanity check of the ring
>>>>>> buffer
>>>>>> size.
>>>>> In this loop I have:
>>>>> resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
>>>>> and the RING_GET_RESPONSE macro is designed in the way that
>>>>> it wraps around when *i* in the question gets bigger than
>>>>> the ring size:
>>>>>
>>>>> #define RING_GET_REQUEST(_r, _idx) \
>>>>> (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
>>>>>
>>>>> So, even if the counter has a bogus number it will not last long
>>>> Hm, this prevents from accessing outside the ring buffer, but does it
>>>> change the loop behavior?
>>> no, it doesn't
>>>> Suppose channel->u.req.ring_rsp_cons = 1, and rp = 0, the loop below
>>>> would still consume the whole 32bit counts, no?
>>>>
>>>> for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
>>>> resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
>>>> ...
>>>> }
>>> You are right here and the comment is totally valid.
>>> I'll put an additional check like here [1] and here [2]
>>> Will this address your comment?
>> Yep, this kind of sanity checks should work.
>>
> Great, will implement the checks this way then
Well, after thinking a bit more on that and chatting on #xendevel IRC
with Juergen (he is on CC list), it seems that the way the code is now
it is all fine without the checks: the assumption here is that
the backend is trusted to always write sane values to the ring counters,
thus no overflow checks on frontend side are required.
Even if I implement the checks then I have no means to recover, but just
print
an error message and bail out not handling any responses.
This is probably why the checks [1] and [2] are only implemented for the
backend side and there are no such macros for the frontend side.
Takashi, please let me know if the above sounds reasonable and
addresses your comments.
>> thanks,
>>
>> Takashi
> Thank you,
> Oleksandr
>>>> Takashi
>>> Thank you,
>>> Oleksandr
>>>
>>> [1]
>>> https://elixir.bootlin.com/linux/v4.17-rc2/source/drivers/block/xen-blkback/blkback.c#L1127
>>>
>>> [2]
>>> https://elixir.bootlin.com/linux/v4.17-rc2/source/drivers/block/xen-blkback/blkback.c#L1135
>>>
>>>
>
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling
2018-04-25 8:26 ` Oleksandr Andrushchenko
@ 2018-04-25 9:02 ` Takashi Iwai
2018-04-25 9:04 ` Oleksandr Andrushchenko
0 siblings, 1 reply; 40+ messages in thread
From: Takashi Iwai @ 2018-04-25 9:02 UTC (permalink / raw)
To: Oleksandr Andrushchenko
Cc: alsa-devel, xen-devel, boris.ostrovsky, konrad.wilk, perex,
Juergen Gross, linux-kernel, Oleksandr Andrushchenko
On Wed, 25 Apr 2018 10:26:34 +0200,
Oleksandr Andrushchenko wrote:
>
> On 04/24/2018 07:23 PM, Oleksandr Andrushchenko wrote:
> > On 04/24/2018 06:02 PM, Takashi Iwai wrote:
> >> On Tue, 24 Apr 2018 16:58:43 +0200,
> >> Oleksandr Andrushchenko wrote:
> >>> On 04/24/2018 05:35 PM, Takashi Iwai wrote:
> >>>> On Tue, 24 Apr 2018 16:29:15 +0200,
> >>>> Oleksandr Andrushchenko wrote:
> >>>>> On 04/24/2018 05:20 PM, Takashi Iwai wrote:
> >>>>>> On Mon, 16 Apr 2018 08:24:51 +0200,
> >>>>>> Oleksandr Andrushchenko wrote:
> >>>>>>> +static irqreturn_t evtchnl_interrupt_req(int irq, void *dev_id)
> >>>>>>> +{
> >>>>>>> + struct xen_snd_front_evtchnl *channel = dev_id;
> >>>>>>> + struct xen_snd_front_info *front_info = channel->front_info;
> >>>>>>> + struct xensnd_resp *resp;
> >>>>>>> + RING_IDX i, rp;
> >>>>>>> + unsigned long flags;
> >>>>>>> +
> >>>>>>> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
> >>>>>>> + return IRQ_HANDLED;
> >>>>>>> +
> >>>>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
> >>>>>>> +
> >>>>>>> +again:
> >>>>>>> + rp = channel->u.req.ring.sring->rsp_prod;
> >>>>>>> + /* ensure we see queued responses up to rp */
> >>>>>>> + rmb();
> >>>>>>> +
> >>>>>>> + for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
> >>>>>> I'm not familiar with Xen stuff in general, but through a quick
> >>>>>> glance, this kind of code worries me a bit.
> >>>>>>
> >>>>>> If channel->u.req.ring.rsp_cons has a bogus number, this may
> >>>>>> lead to a
> >>>>>> very long loop, no? Better to have a sanity check of the ring
> >>>>>> buffer
> >>>>>> size.
> >>>>> In this loop I have:
> >>>>> resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
> >>>>> and the RING_GET_RESPONSE macro is designed in the way that
> >>>>> it wraps around when *i* in the question gets bigger than
> >>>>> the ring size:
> >>>>>
> >>>>> #define RING_GET_REQUEST(_r, _idx) \
> >>>>> (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
> >>>>>
> >>>>> So, even if the counter has a bogus number it will not last long
> >>>> Hm, this prevents from accessing outside the ring buffer, but does it
> >>>> change the loop behavior?
> >>> no, it doesn't
> >>>> Suppose channel->u.req.ring_rsp_cons = 1, and rp = 0, the loop below
> >>>> would still consume the whole 32bit counts, no?
> >>>>
> >>>> for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
> >>>> resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
> >>>> ...
> >>>> }
> >>> You are right here and the comment is totally valid.
> >>> I'll put an additional check like here [1] and here [2]
> >>> Will this address your comment?
> >> Yep, this kind of sanity checks should work.
> >>
> > Great, will implement the checks this way then
> Well, after thinking a bit more on that and chatting on #xendevel IRC
> with Juergen (he is on CC list), it seems that the way the code is now
> it is all fine without the checks: the assumption here is that
> the backend is trusted to always write sane values to the ring counters,
> thus no overflow checks on frontend side are required.
> Even if I implement the checks then I have no means to recover, but
> just print
> an error message and bail out not handling any responses.
> This is probably why the checks [1] and [2] are only implemented for the
> backend side and there are no such macros for the frontend side.
>
> Takashi, please let me know if the above sounds reasonable and
> addresses your comments.
If it's guaranteed to work, that's OK.
But maybe it's worth to comment for readers.
thanks,
Takashi
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling
2018-04-25 9:02 ` Takashi Iwai
@ 2018-04-25 9:04 ` Oleksandr Andrushchenko
0 siblings, 0 replies; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-04-25 9:04 UTC (permalink / raw)
To: Takashi Iwai
Cc: alsa-devel, xen-devel, boris.ostrovsky, konrad.wilk, perex,
Juergen Gross, linux-kernel, Oleksandr Andrushchenko
On 04/25/2018 12:02 PM, Takashi Iwai wrote:
> On Wed, 25 Apr 2018 10:26:34 +0200,
> Oleksandr Andrushchenko wrote:
>> On 04/24/2018 07:23 PM, Oleksandr Andrushchenko wrote:
>>> On 04/24/2018 06:02 PM, Takashi Iwai wrote:
>>>> On Tue, 24 Apr 2018 16:58:43 +0200,
>>>> Oleksandr Andrushchenko wrote:
>>>>> On 04/24/2018 05:35 PM, Takashi Iwai wrote:
>>>>>> On Tue, 24 Apr 2018 16:29:15 +0200,
>>>>>> Oleksandr Andrushchenko wrote:
>>>>>>> On 04/24/2018 05:20 PM, Takashi Iwai wrote:
>>>>>>>> On Mon, 16 Apr 2018 08:24:51 +0200,
>>>>>>>> Oleksandr Andrushchenko wrote:
>>>>>>>>> +static irqreturn_t evtchnl_interrupt_req(int irq, void *dev_id)
>>>>>>>>> +{
>>>>>>>>> + struct xen_snd_front_evtchnl *channel = dev_id;
>>>>>>>>> + struct xen_snd_front_info *front_info = channel->front_info;
>>>>>>>>> + struct xensnd_resp *resp;
>>>>>>>>> + RING_IDX i, rp;
>>>>>>>>> + unsigned long flags;
>>>>>>>>> +
>>>>>>>>> + if (unlikely(channel->state != EVTCHNL_STATE_CONNECTED))
>>>>>>>>> + return IRQ_HANDLED;
>>>>>>>>> +
>>>>>>>>> + spin_lock_irqsave(&front_info->io_lock, flags);
>>>>>>>>> +
>>>>>>>>> +again:
>>>>>>>>> + rp = channel->u.req.ring.sring->rsp_prod;
>>>>>>>>> + /* ensure we see queued responses up to rp */
>>>>>>>>> + rmb();
>>>>>>>>> +
>>>>>>>>> + for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
>>>>>>>> I'm not familiar with Xen stuff in general, but through a quick
>>>>>>>> glance, this kind of code worries me a bit.
>>>>>>>>
>>>>>>>> If channel->u.req.ring.rsp_cons has a bogus number, this may
>>>>>>>> lead to a
>>>>>>>> very long loop, no? Better to have a sanity check of the ring
>>>>>>>> buffer
>>>>>>>> size.
>>>>>>> In this loop I have:
>>>>>>> resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
>>>>>>> and the RING_GET_RESPONSE macro is designed in the way that
>>>>>>> it wraps around when *i* in the question gets bigger than
>>>>>>> the ring size:
>>>>>>>
>>>>>>> #define RING_GET_REQUEST(_r, _idx) \
>>>>>>> (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
>>>>>>>
>>>>>>> So, even if the counter has a bogus number it will not last long
>>>>>> Hm, this prevents from accessing outside the ring buffer, but does it
>>>>>> change the loop behavior?
>>>>> no, it doesn't
>>>>>> Suppose channel->u.req.ring_rsp_cons = 1, and rp = 0, the loop below
>>>>>> would still consume the whole 32bit counts, no?
>>>>>>
>>>>>> for (i = channel->u.req.ring.rsp_cons; i != rp; i++) {
>>>>>> resp = RING_GET_RESPONSE(&channel->u.req.ring, i);
>>>>>> ...
>>>>>> }
>>>>> You are right here and the comment is totally valid.
>>>>> I'll put an additional check like here [1] and here [2]
>>>>> Will this address your comment?
>>>> Yep, this kind of sanity checks should work.
>>>>
>>> Great, will implement the checks this way then
>> Well, after thinking a bit more on that and chatting on #xendevel IRC
>> with Juergen (he is on CC list), it seems that the way the code is now
>> it is all fine without the checks: the assumption here is that
>> the backend is trusted to always write sane values to the ring counters,
>> thus no overflow checks on frontend side are required.
>> Even if I implement the checks then I have no means to recover, but
>> just print
>> an error message and bail out not handling any responses.
>> This is probably why the checks [1] and [2] are only implemented for the
>> backend side and there are no such macros for the frontend side.
>>
>> Takashi, please let me know if the above sounds reasonable and
>> addresses your comments.
> If it's guaranteed to work, that's OK.
> But maybe it's worth to comment for readers.
ok, will put a comment on that
>
> thanks,
>
> Takashi
Thank you,
Oleksandr
^ permalink raw reply [flat|nested] 40+ messages in thread
* Re: [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver
2018-04-16 6:24 [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver Oleksandr Andrushchenko
` (6 preceding siblings ...)
2018-04-18 15:15 ` Oleksandr Andrushchenko
@ 2018-05-02 7:59 ` Oleksandr Andrushchenko
7 siblings, 0 replies; 40+ messages in thread
From: Oleksandr Andrushchenko @ 2018-05-02 7:59 UTC (permalink / raw)
To: xen-devel, linux-kernel, alsa-devel, jgross, boris.ostrovsky,
konrad.wilk, perex, tiwai
Cc: Oleksandr Andrushchenko
Gentle reminder...
I think that Xen side comments are already there and still I miss
some input from ALSA community on patch #5.
Thank you,
Oleksandr
On 04/16/2018 09:24 AM, Oleksandr Andrushchenko wrote:
> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
>
> Please note: this patch series depends on [3].
>
> This patch series adds support for Xen [1] para-virtualized
> sound frontend driver. It implements the protocol from
> include/xen/interface/io/sndif.h with the following limitations:
> - mute/unmute is not supported
> - get/set volume is not supported
> Volume control is not supported for the reason that most of the
> use-cases (at the moment) are based on scenarious where
> unprivileged OS (e.g. Android, AGL etc) use software mixers.
>
> Both capture and playback are supported.
>
> Corresponding backend, implemented as a user-space application, can be
> found at [2].
>
> Thank you,
> Oleksandr
>
> Changes since v1:
> *****************
>
> 1. Moved driver from sound/drivers to sound/xen
>
> 2. Coding style changes to better meet Linux Kernel
>
> 3. Added explicit back and front synchronization
> In order to provide explicit synchronization between backend and
> frontend the following changes are introduced in the protocol:
> - add new ring buffer for sending asynchronous events from
> backend to frontend to report number of bytes played by the
> frontend (XENSND_EVT_CUR_POS)
> - introduce trigger events for playback control: start/stop/pause/resume
> - add "req-" prefix to event-channel and ring-ref to unify naming
> of the Xen event channels for requests and events
>
> 4. Added explicit back and front parameter negotiation
> In order to provide explicit stream parameter negotiation between
> backend and frontend the following changes are introduced in the protocol:
> add XENSND_OP_HW_PARAM_QUERY request to read/update
> configuration space for the parameters given: request passes
> desired parameter's intervals/masks and the response to this request
> returns allowed min/max intervals/masks to be used.
>
> [1] https://xenproject.org/
> [2] https://github.com/xen-troops/snd_be
> [3] https://lkml.org/lkml/2018/4/12/522
>
> Oleksandr Andrushchenko (5):
> ALSA: xen-front: Introduce Xen para-virtualized sound frontend driver
> ALSA: xen-front: Read sound driver configuration from Xen store
> ALSA: xen-front: Implement Xen event channel handling
> ALSA: xen-front: Implement handling of shared buffers
> ALSA: xen-front: Implement ALSA virtual sound driver
>
> sound/Kconfig | 2 +
> sound/Makefile | 2 +-
> sound/xen/Kconfig | 10 +
> sound/xen/Makefile | 9 +
> sound/xen/xen_snd_front.c | 410 +++++++++++++++++++
> sound/xen/xen_snd_front.h | 57 +++
> sound/xen/xen_snd_front_alsa.c | 830 ++++++++++++++++++++++++++++++++++++++
> sound/xen/xen_snd_front_alsa.h | 23 ++
> sound/xen/xen_snd_front_cfg.c | 517 ++++++++++++++++++++++++
> sound/xen/xen_snd_front_cfg.h | 46 +++
> sound/xen/xen_snd_front_evtchnl.c | 478 ++++++++++++++++++++++
> sound/xen/xen_snd_front_evtchnl.h | 92 +++++
> sound/xen/xen_snd_front_shbuf.c | 193 +++++++++
> sound/xen/xen_snd_front_shbuf.h | 36 ++
> 14 files changed, 2704 insertions(+), 1 deletion(-)
> create mode 100644 sound/xen/Kconfig
> create mode 100644 sound/xen/Makefile
> create mode 100644 sound/xen/xen_snd_front.c
> create mode 100644 sound/xen/xen_snd_front.h
> create mode 100644 sound/xen/xen_snd_front_alsa.c
> create mode 100644 sound/xen/xen_snd_front_alsa.h
> create mode 100644 sound/xen/xen_snd_front_cfg.c
> create mode 100644 sound/xen/xen_snd_front_cfg.h
> create mode 100644 sound/xen/xen_snd_front_evtchnl.c
> create mode 100644 sound/xen/xen_snd_front_evtchnl.h
> create mode 100644 sound/xen/xen_snd_front_shbuf.c
> create mode 100644 sound/xen/xen_snd_front_shbuf.h
>
^ permalink raw reply [flat|nested] 40+ messages in thread
end of thread, other threads:[~2018-05-02 7:59 UTC | newest]
Thread overview: 40+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-04-16 6:24 [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver Oleksandr Andrushchenko
2018-04-16 6:24 ` [PATCH v2 1/5] ALSA: xen-front: Introduce Xen para-virtualized sound " Oleksandr Andrushchenko
2018-04-16 12:25 ` Juergen Gross
2018-04-17 8:24 ` Oleksandr Andrushchenko
2018-04-24 13:55 ` Takashi Iwai
2018-04-24 13:59 ` Oleksandr Andrushchenko
2018-04-16 6:24 ` [PATCH v2 2/5] ALSA: xen-front: Read sound driver configuration from Xen store Oleksandr Andrushchenko
2018-04-16 12:55 ` Juergen Gross
2018-04-17 8:42 ` Oleksandr Andrushchenko
2018-04-17 11:08 ` Juergen Gross
2018-04-16 6:24 ` [PATCH v2 3/5] ALSA: xen-front: Implement Xen event channel handling Oleksandr Andrushchenko
2018-04-16 13:12 ` Juergen Gross
2018-04-17 8:58 ` Oleksandr Andrushchenko
2018-04-17 11:14 ` Juergen Gross
2018-04-17 11:21 ` Oleksandr Andrushchenko
2018-04-16 13:53 ` kbuild test robot
2018-04-24 14:20 ` Takashi Iwai
2018-04-24 14:29 ` Oleksandr Andrushchenko
2018-04-24 14:35 ` Takashi Iwai
2018-04-24 14:58 ` Oleksandr Andrushchenko
2018-04-24 15:02 ` Takashi Iwai
2018-04-24 16:23 ` Oleksandr Andrushchenko
2018-04-25 8:26 ` Oleksandr Andrushchenko
2018-04-25 9:02 ` Takashi Iwai
2018-04-25 9:04 ` Oleksandr Andrushchenko
2018-04-16 6:24 ` [PATCH v2 4/5] ALSA: xen-front: Implement handling of shared buffers Oleksandr Andrushchenko
2018-04-16 13:39 ` Juergen Gross
2018-04-17 9:22 ` Oleksandr Andrushchenko
2018-04-17 11:15 ` Juergen Gross
2018-04-16 6:24 ` [PATCH v2 5/5] ALSA: xen-front: Implement ALSA virtual sound driver Oleksandr Andrushchenko
2018-04-16 14:09 ` Juergen Gross
2018-04-17 11:32 ` Oleksandr Andrushchenko
2018-04-17 12:26 ` Oleksandr Andrushchenko
2018-04-17 12:32 ` Juergen Gross
2018-04-17 12:34 ` Oleksandr Andrushchenko
2018-04-16 14:59 ` kbuild test robot
2018-04-17 12:42 ` [PATCH v2 0/5] ALSA: xen-front: Add Xen para-virtualized frontend driver Oleksandr Andrushchenko
2018-04-18 15:15 ` Oleksandr Andrushchenko
2018-04-23 6:34 ` Oleksandr Andrushchenko
2018-05-02 7:59 ` Oleksandr Andrushchenko
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