[Qemu-devel] [PATCH v6 00/12] vhost-user-backend & vhost-user-input

[Qemu-devel] [PATCH v6 00/12] vhost-user-backend & vhost-user-input

[Marc-André Lureau]

Hi,

This series is based on previously discussed "[PATCH v4 00/29]
vhost-user for input & GPU" and "vhost-user: define conventions for
vhost-user backends" work. The GPU part is left off for now.

This series introduces a "vhost-user-backend": an helper object to be
used by vhost-user devices to ease with backend initialization and
handling. As a simple showcase, a "vhost-user-input-pci" device is
introduced, which can be used with the "contrib: add vhost-user-input"
example. vhost-user-input isn't meant to be installed, discovered or
used by libvirt: no installation is done (no vhost-user JSON file is
provided either).

thanks

v6:
- rebased, kconfig update

v5:
- rebased
- removed useless "child" struct field leftover
- add Gerd r-b tags

v4:
- drop "RFC: add explicit can_migrate to vhost_user_backend_dev_init()"
- remove useless "cmd" struct field leftover

v3:
- add previously sent patch "libvhost-user: fix clang enum-conversion
  warning" to fix clang build
- "define conventions for vhost-user backends" updates after Eric review
- Drop user-creatable from vhost-user-backend
- Make vhost-user-input-pci take a chardev= (instead of vhost-user=)

v2:
- rebased (VhostUserInputPCI got most of the changes, due to split)
- added "RFC: add explicit can_migrate to
  vhost_user_backend_dev_init()" to attempt to address Michael
  concerns about migration.

Marc-André Lureau (12):
  libvhost-user: fix clang enum-conversion warning
  vhost-user: define conventions for vhost-user backends
  vhost-user: simplify vhost_user_init/vhost_user_cleanup
  libvhost-user: exit by default on VHOST_USER_NONE
  vhost-user: wrap some read/write with retry handling
  Add vhost-user-backend
  vhost-user: split vhost_user_read()
  vhost-user: add vhost_user_input_get_config()
  libvhost-user-glib: export vug_source_new()
  libvhost-user: add vu_queue_unpop()
  Add vhost-user-input-pci
  contrib: add vhost-user-input

 contrib/libvhost-user/libvhost-user-glib.h |   3 +
 contrib/libvhost-user/libvhost-user.h      |  17 +-
 include/hw/virtio/vhost-backend.h          |   4 +
 include/hw/virtio/vhost-user-blk.h         |   2 +-
 include/hw/virtio/vhost-user-scsi.h        |   2 +-
 include/hw/virtio/vhost-user.h             |   2 +-
 include/hw/virtio/virtio-input.h           |  14 +
 include/sysemu/vhost-user-backend.h        |  57 +++
 backends/cryptodev-vhost-user.c            |  18 +-
 backends/vhost-user.c                      | 209 +++++++++++
 contrib/libvhost-user/libvhost-user-glib.c |  11 +-
 contrib/libvhost-user/libvhost-user.c      |  19 +-
 contrib/vhost-user-input/main.c            | 398 +++++++++++++++++++++
 hw/block/vhost-user-blk.c                  |  22 +-
 hw/input/vhost-user-input.c                |  99 +++++
 hw/scsi/vhost-user-scsi.c                  |  20 +-
 hw/virtio/vhost-stub.c                     |   4 +-
 hw/virtio/vhost-user-input-pci.c           |  53 +++
 hw/virtio/vhost-user.c                     | 118 +++++-
 net/vhost-user.c                           |  13 +-
 MAINTAINERS                                |   5 +
 Makefile                                   |   3 +
 Makefile.objs                              |   1 +
 backends/Makefile.objs                     |   3 +
 configure                                  |   3 +
 contrib/vhost-user-input/Makefile.objs     |   1 +
 docs/interop/vhost-user.json               | 232 ++++++++++++
 docs/interop/vhost-user.txt                | 109 +++++-
 hw/input/Kconfig                           |   5 +
 hw/input/Makefile.objs                     |   1 +
 hw/virtio/Makefile.objs                    |   1 +
 31 files changed, 1363 insertions(+), 86 deletions(-)
 create mode 100644 include/sysemu/vhost-user-backend.h
 create mode 100644 backends/vhost-user.c
 create mode 100644 contrib/vhost-user-input/main.c
 create mode 100644 hw/input/vhost-user-input.c
 create mode 100644 hw/virtio/vhost-user-input-pci.c
 create mode 100644 contrib/vhost-user-input/Makefile.objs
 create mode 100644 docs/interop/vhost-user.json

-- 
2.21.0.4.g36eb1cb9cf

[Qemu-devel] [PATCH v6 01/12] libvhost-user: fix clang enum-conversion warning

[Marc-André Lureau]

Now that the VhostUserMsg.request field is used for both master &
slave requests, since commit d84599f56c820d8c1ac9928a76500dcdfbbf194d:

contrib/libvhost-user/libvhost-user.c:953:20: error: implicit conversion from enumeration type 'enum VhostUserSlaveRequest' to different enumeration type 'VhostUserRequest' (aka 'enum VhostUserRequest') [-Werror,-Wenum-conversion]
        .request = VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG,
                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 contrib/libvhost-user/libvhost-user.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/contrib/libvhost-user/libvhost-user.h b/contrib/libvhost-user/libvhost-user.h
index 4aa55b4d2d..c0133b7f3f 100644
--- a/contrib/libvhost-user/libvhost-user.h
+++ b/contrib/libvhost-user/libvhost-user.h
@@ -145,7 +145,7 @@ typedef struct VhostUserVringArea {
 #endif
 
 typedef struct VhostUserMsg {
-    VhostUserRequest request;
+    int request;
 
 #define VHOST_USER_VERSION_MASK     (0x3)
 #define VHOST_USER_REPLY_MASK       (0x1 << 2)
-- 
2.21.0.4.g36eb1cb9cf

[Qemu-devel] [PATCH v6 02/12] vhost-user: define conventions for vhost-user backends

[Marc-André Lureau]

As discussed during "[PATCH v4 00/29] vhost-user for input & GPU"
review, let's define a common set of backend conventions to help with
management layer implementation, and interoperability.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
---
 MAINTAINERS                  |   1 +
 docs/interop/vhost-user.json | 232 +++++++++++++++++++++++++++++++++++
 docs/interop/vhost-user.txt  | 101 ++++++++++++++-
 3 files changed, 332 insertions(+), 2 deletions(-)
 create mode 100644 docs/interop/vhost-user.json

diff --git a/MAINTAINERS b/MAINTAINERS
index 074ad46d47..d811c968ee 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1451,6 +1451,7 @@ vhost
 M: Michael S. Tsirkin <mst@redhat.com>
 S: Supported
 F: hw/*/*vhost*
+F: docs/interop/vhost-user.json
 F: docs/interop/vhost-user.txt
 F: contrib/vhost-user-*/
 
diff --git a/docs/interop/vhost-user.json b/docs/interop/vhost-user.json
new file mode 100644
index 0000000000..ae88c03117
--- /dev/null
+++ b/docs/interop/vhost-user.json
@@ -0,0 +1,232 @@
+# -*- Mode: Python -*-
+#
+# Copyright (C) 2018 Red Hat, Inc.
+#
+# Authors:
+#  Marc-André Lureau <marcandre.lureau@redhat.com>
+#
+# This work is licensed under the terms of the GNU GPL, version 2 or
+# later. See the COPYING file in the top-level directory.
+
+##
+# = vhost user backend discovery & capabilities
+##
+
+##
+# @VHostUserBackendType:
+#
+# List the various vhost user backend types.
+#
+# @9p: 9p virtio console
+# @balloon: virtio balloon
+# @block: virtio block
+# @caif: virtio caif
+# @console: virtio console
+# @crypto: virtio crypto
+# @gpu: virtio gpu
+# @input: virtio input
+# @net: virtio net
+# @rng: virtio rng
+# @rpmsg: virtio remote processor messaging
+# @rproc-serial: virtio remoteproc serial link
+# @scsi: virtio scsi
+# @vsock: virtio vsock transport
+#
+# Since: 4.0
+##
+{
+  'enum': 'VHostUserBackendType',
+  'data': [
+      '9p',
+      'balloon',
+      'block',
+      'caif',
+      'console',
+      'crypto',
+      'gpu',
+      'input',
+      'net',
+      'rng',
+      'rpmsg',
+      'rproc-serial',
+      'scsi',
+      'vsock'
+  ]
+}
+
+##
+# @VHostUserBackendInputFeature:
+#
+# List of vhost user "input" features.
+#
+# @evdev-path: The --evdev-path command line option is supported.
+# @no-grab: The --no-grab command line option is supported.
+#
+# Since: 4.0
+##
+{
+  'enum': 'VHostUserBackendInputFeature',
+  'data': [ 'evdev-path', 'no-grab' ]
+}
+
+##
+# @VHostUserBackendCapabilitiesInput:
+#
+# Capabilities reported by vhost user "input" backends
+#
+# @features: list of supported features.
+#
+# Since: 4.0
+##
+{
+  'struct': 'VHostUserBackendCapabilitiesInput',
+  'data': {
+    'features': [ 'VHostUserBackendInputFeature' ]
+  }
+}
+
+##
+# @VHostUserBackendGPUFeature:
+#
+# List of vhost user "gpu" features.
+#
+# @render-node: The --render-node command line option is supported.
+# @virgl: The --virgl command line option is supported.
+#
+# Since: 4.0
+##
+{
+  'enum': 'VHostUserBackendGPUFeature',
+  'data': [ 'render-node', 'virgl' ]
+}
+
+##
+# @VHostUserBackendCapabilitiesGPU:
+#
+# Capabilities reported by vhost user "gpu" backends.
+#
+# @features: list of supported features.
+#
+# Since: 4.0
+##
+{
+  'struct': 'VHostUserBackendCapabilitiesGPU',
+  'data': {
+    'features': [ 'VHostUserBackendGPUFeature' ]
+  }
+}
+
+##
+# @VHostUserBackendCapabilities:
+#
+# Capabilities reported by vhost user backends.
+#
+# @type: The vhost user backend type.
+#
+# Since: 4.0
+##
+{
+  'union': 'VHostUserBackendCapabilities',
+  'base': { 'type': 'VHostUserBackendType' },
+  'discriminator': 'type',
+  'data': {
+    'input': 'VHostUserBackendCapabilitiesInput',
+    'gpu': 'VHostUserBackendCapabilitiesGPU'
+  }
+}
+
+##
+# @VhostUserBackend:
+#
+# Describes a vhost user backend to management software.
+#
+# It is possible for multiple @VhostUserBackend elements to match the
+# search criteria of management software. Applications thus need rules
+# to pick one of the many matches, and users need the ability to
+# override distro defaults.
+#
+# It is recommended to create vhost user backend JSON files (each
+# containing a single @VhostUserBackend root element) with a
+# double-digit prefix, for example "50-qemu-gpu.json",
+# "50-crosvm-gpu.json", etc, so they can be sorted in predictable
+# order. The backend JSON files should be searched for in three
+# directories:
+#
+#   - /usr/share/qemu/vhost-user -- populated by distro-provided
+#                                   packages (XDG_DATA_DIRS covers
+#                                   /usr/share by default),
+#
+#   - /etc/qemu/vhost-user -- exclusively for sysadmins' local additions,
+#
+#   - $XDG_CONFIG_HOME/qemu/vhost-user -- exclusively for per-user local
+#                                         additions (XDG_CONFIG_HOME
+#                                         defaults to $HOME/.config).
+#
+# Top-down, the list of directories goes from general to specific.
+#
+# Management software should build a list of files from all three
+# locations, then sort the list by filename (i.e., basename
+# component). Management software should choose the first JSON file on
+# the sorted list that matches the search criteria. If a more specific
+# directory has a file with same name as a less specific directory,
+# then the file in the more specific directory takes effect. If the
+# more specific file is zero length, it hides the less specific one.
+#
+# For example, if a distro ships
+#
+#   - /usr/share/qemu/vhost-user/50-qemu-gpu.json
+#
+#   - /usr/share/qemu/vhost-user/50-crosvm-gpu.json
+#
+# then the sysadmin can prevent the default QEMU being used at all with
+#
+#   $ touch /etc/qemu/vhost-user/50-qemu-gpu.json
+#
+# The sysadmin can replace/alter the distro default OVMF with
+#
+#   $ vim /etc/qemu/vhost-user/50-qemu-gpu.json
+#
+# or they can provide a parallel QEMU GPU with higher priority
+#
+#   $ vim /etc/qemu/vhost-user/10-qemu-gpu.json
+#
+# or they can provide a parallel OVMF with lower priority
+#
+#   $ vim /etc/qemu/vhost-user/99-qemu-gpu.json
+#
+# @type: The vhost user backend type.
+#
+# @description: Provides a human-readable description of the backend.
+#               Management software may or may not display @description.
+#
+# @binary: Absolute path to the backend binary.
+#
+# @tags: An optional list of auxiliary strings associated with the
+#        backend for which @description is not appropriate, due to the
+#        latter's possible exposure to the end-user. @tags serves
+#        development and debugging purposes only, and management
+#        software shall explicitly ignore it.
+#
+# Since: 4.0
+#
+# Example:
+#
+# {
+#   "description": "QEMU vhost-user-gpu",
+#   "type": "gpu",
+#   "binary": "/usr/libexec/qemu/vhost-user-gpu",
+#   "tags": [
+#     "CONFIG_OPENGL_DMABUF=y"
+#   ]
+# }
+#
+##
+{
+  'struct' : 'VhostUserBackend',
+  'data'   : {
+    'description': 'str',
+    'type': 'VHostUserBackendType',
+    'binary': 'str',
+    '*tags': [ 'str' ]
+  }
+}
diff --git a/docs/interop/vhost-user.txt b/docs/interop/vhost-user.txt
index c2194711d9..9ee2a60cfb 100644
--- a/docs/interop/vhost-user.txt
+++ b/docs/interop/vhost-user.txt
@@ -17,8 +17,13 @@ The protocol defines 2 sides of the communication, master and slave. Master is
 the application that shares its virtqueues, in our case QEMU. Slave is the
 consumer of the virtqueues.
 
-In the current implementation QEMU is the Master, and the Slave is intended to
-be a software Ethernet switch running in user space, such as Snabbswitch.
+In the current implementation QEMU is the Master, and the Slave is the
+external process consuming the virtio queues, for example a software
+Ethernet switch running in user space, such as Snabbswitch, or a block
+device backend processing read & write to a virtual disk. In order to
+facilitate interoperability between various backend implementations,
+it is recommended to follow the "Backend program conventions"
+described in this document.
 
 Master and slave can be either a client (i.e. connecting) or server (listening)
 in the socket communication.
@@ -835,3 +840,95 @@ resilient for selective requests.
 For the message types that already solicit a reply from the client, the
 presence of VHOST_USER_PROTOCOL_F_REPLY_ACK or need_reply bit being set brings
 no behavioural change. (See the 'Communication' section for details.)
+
+Backend program conventions
+---------------------------
+
+vhost-user backends can provide various devices & services and may
+need to be configured manually depending on the use case. However, it
+is a good idea to follow the conventions listed here when
+possible. Users, QEMU or libvirt, can then rely on some common
+behaviour to avoid heterogenous configuration and management of the
+backend programs and facilitate interoperability.
+
+Each backend installed on a host system should come with at least one
+JSON file that conforms to the vhost-user.json schema. Each file
+informs the management applications about the backend type, and binary
+location. In addition, it defines rules for management apps for
+picking the highest priority backend when multiple match the search
+criteria (see @VhostUserBackend documentation in the schema file).
+
+If the backend is not capable of enabling a requested feature on the
+host (such as 3D acceleration with virgl), or the initialization
+failed, the backend should fail to start early and exit with a status
+!= 0. It may also print a message to stderr for further details.
+
+The backend program must not daemonize itself, but it may be
+daemonized by the management layer. It may also have a restricted
+access to the system.
+
+File descriptors 0, 1 and 2 will exist, and have regular
+stdin/stdout/stderr usage (they may have been redirected to /dev/null
+by the management layer, or to a log handler).
+
+The backend program must end (as quickly and cleanly as possible) when
+the SIGTERM signal is received. Eventually, it may receive SIGKILL by
+the management layer after a few seconds.
+
+The following command line options have an expected behaviour. They
+are mandatory, unless explicitly said differently:
+
+* --socket-path=PATH
+
+This option specify the location of the vhost-user Unix domain socket.
+It is incompatible with --fd.
+
+* --fd=FDNUM
+
+When this argument is given, the backend program is started with the
+vhost-user socket as file descriptor FDNUM. It is incompatible with
+--socket-path.
+
+* --print-capabilities
+
+Output to stdout the backend capabilities in JSON format, and then
+exit successfully. Other options and arguments should be ignored, and
+the backend program should not perform its normal function.  The
+capabilities can be reported dynamically depending on the host
+capabilities.
+
+The JSON output is described in the vhost-user.json schema, by
+@VHostUserBackendCapabilities.  Example:
+{
+  "type": "foo",
+  "features": [
+    "feature-a",
+    "feature-b"
+  ]
+}
+
+vhost-user-input
+----------------
+
+Command line options:
+
+* --evdev-path=PATH (optional)
+
+Specify the linux input device.
+
+* --no-grab (optional)
+
+Do no request exclusive access to the input device.
+
+vhost-user-gpu
+--------------
+
+Command line options:
+
+* --render-node=PATH (optional)
+
+Specify the GPU DRM render node.
+
+* --virgl (optional)
+
+Enable virgl rendering support.
-- 
2.21.0.4.g36eb1cb9cf

[Qemu-devel] [PATCH v6 03/12] vhost-user: simplify vhost_user_init/vhost_user_cleanup

[Marc-André Lureau]

Take a VhostUserState* that can be pre-allocated, and initialize it
with the associated chardev.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Tiwei Bie <tiwei.bie@intel.com>
---
 include/hw/virtio/vhost-user-blk.h  |  2 +-
 include/hw/virtio/vhost-user-scsi.h |  2 +-
 include/hw/virtio/vhost-user.h      |  2 +-
 backends/cryptodev-vhost-user.c     | 18 ++++--------------
 hw/block/vhost-user-blk.c           | 22 ++++------------------
 hw/scsi/vhost-user-scsi.c           | 20 ++++----------------
 hw/virtio/vhost-stub.c              |  4 ++--
 hw/virtio/vhost-user.c              | 16 ++++++++++++----
 net/vhost-user.c                    | 13 ++++---------
 9 files changed, 33 insertions(+), 66 deletions(-)

diff --git a/include/hw/virtio/vhost-user-blk.h b/include/hw/virtio/vhost-user-blk.h
index d52944aeeb..a8a106eecb 100644
--- a/include/hw/virtio/vhost-user-blk.h
+++ b/include/hw/virtio/vhost-user-blk.h
@@ -36,7 +36,7 @@ typedef struct VHostUserBlk {
     uint32_t queue_size;
     uint32_t config_wce;
     struct vhost_dev dev;
-    VhostUserState *vhost_user;
+    VhostUserState vhost_user;
 } VHostUserBlk;
 
 #endif
diff --git a/include/hw/virtio/vhost-user-scsi.h b/include/hw/virtio/vhost-user-scsi.h
index e429cacd8e..738f9288bd 100644
--- a/include/hw/virtio/vhost-user-scsi.h
+++ b/include/hw/virtio/vhost-user-scsi.h
@@ -30,7 +30,7 @@
 
 typedef struct VHostUserSCSI {
     VHostSCSICommon parent_obj;
-    VhostUserState *vhost_user;
+    VhostUserState vhost_user;
 } VHostUserSCSI;
 
 #endif /* VHOST_USER_SCSI_H */
diff --git a/include/hw/virtio/vhost-user.h b/include/hw/virtio/vhost-user.h
index fd660393a0..811e325f42 100644
--- a/include/hw/virtio/vhost-user.h
+++ b/include/hw/virtio/vhost-user.h
@@ -22,7 +22,7 @@ typedef struct VhostUserState {
     VhostUserHostNotifier notifier[VIRTIO_QUEUE_MAX];
 } VhostUserState;
 
-VhostUserState *vhost_user_init(void);
+bool vhost_user_init(VhostUserState *user, CharBackend *chr, Error **errp);
 void vhost_user_cleanup(VhostUserState *user);
 
 #endif
diff --git a/backends/cryptodev-vhost-user.c b/backends/cryptodev-vhost-user.c
index d539f14d59..1052a5d0e9 100644
--- a/backends/cryptodev-vhost-user.c
+++ b/backends/cryptodev-vhost-user.c
@@ -47,7 +47,7 @@
 typedef struct CryptoDevBackendVhostUser {
     CryptoDevBackend parent_obj;
 
-    VhostUserState *vhost_user;
+    VhostUserState vhost_user;
     CharBackend chr;
     char *chr_name;
     bool opened;
@@ -104,7 +104,7 @@ cryptodev_vhost_user_start(int queues,
             continue;
         }
 
-        options.opaque = s->vhost_user;
+        options.opaque = &s->vhost_user;
         options.backend_type = VHOST_BACKEND_TYPE_USER;
         options.cc = b->conf.peers.ccs[i];
         s->vhost_crypto[i] = cryptodev_vhost_init(&options);
@@ -182,7 +182,6 @@ static void cryptodev_vhost_user_init(
     size_t i;
     Error *local_err = NULL;
     Chardev *chr;
-    VhostUserState *user;
     CryptoDevBackendClient *cc;
     CryptoDevBackendVhostUser *s =
                       CRYPTODEV_BACKEND_VHOST_USER(backend);
@@ -213,15 +212,10 @@ static void cryptodev_vhost_user_init(
         }
     }
 
-    user = vhost_user_init();
-    if (!user) {
-        error_setg(errp, "Failed to init vhost_user");
+    if (!vhost_user_init(&s->vhost_user, &s->chr, errp)) {
         return;
     }
 
-    user->chr = &s->chr;
-    s->vhost_user = user;
-
     qemu_chr_fe_set_handlers(&s->chr, NULL, NULL,
                      cryptodev_vhost_user_event, NULL, s, NULL, true);
 
@@ -307,11 +301,7 @@ static void cryptodev_vhost_user_cleanup(
         }
     }
 
-    if (s->vhost_user) {
-        vhost_user_cleanup(s->vhost_user);
-        g_free(s->vhost_user);
-        s->vhost_user = NULL;
-    }
+    vhost_user_cleanup(&s->vhost_user);
 }
 
 static void cryptodev_vhost_user_set_chardev(Object *obj,
diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c
index 44ac814016..767c734a81 100644
--- a/hw/block/vhost-user-blk.c
+++ b/hw/block/vhost-user-blk.c
@@ -253,7 +253,6 @@ static void vhost_user_blk_device_realize(DeviceState *dev, Error **errp)
 {
     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
     VHostUserBlk *s = VHOST_USER_BLK(vdev);
-    VhostUserState *user;
     struct vhost_virtqueue *vqs = NULL;
     int i, ret;
 
@@ -272,15 +271,10 @@ static void vhost_user_blk_device_realize(DeviceState *dev, Error **errp)
         return;
     }
 
-    user = vhost_user_init();
-    if (!user) {
-        error_setg(errp, "vhost-user-blk: failed to init vhost_user");
+    if (!vhost_user_init(&s->vhost_user, &s->chardev, errp)) {
         return;
     }
 
-    user->chr = &s->chardev;
-    s->vhost_user = user;
-
     virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK,
                 sizeof(struct virtio_blk_config));
 
@@ -297,7 +291,7 @@ static void vhost_user_blk_device_realize(DeviceState *dev, Error **errp)
 
     vhost_dev_set_config_notifier(&s->dev, &blk_ops);
 
-    ret = vhost_dev_init(&s->dev, s->vhost_user, VHOST_BACKEND_TYPE_USER, 0);
+    ret = vhost_dev_init(&s->dev, &s->vhost_user, VHOST_BACKEND_TYPE_USER, 0);
     if (ret < 0) {
         error_setg(errp, "vhost-user-blk: vhost initialization failed: %s",
                    strerror(-ret));
@@ -322,10 +316,7 @@ vhost_err:
 virtio_err:
     g_free(vqs);
     virtio_cleanup(vdev);
-
-    vhost_user_cleanup(user);
-    g_free(user);
-    s->vhost_user = NULL;
+    vhost_user_cleanup(&s->vhost_user);
 }
 
 static void vhost_user_blk_device_unrealize(DeviceState *dev, Error **errp)
@@ -338,12 +329,7 @@ static void vhost_user_blk_device_unrealize(DeviceState *dev, Error **errp)
     vhost_dev_cleanup(&s->dev);
     g_free(vqs);
     virtio_cleanup(vdev);
-
-    if (s->vhost_user) {
-        vhost_user_cleanup(s->vhost_user);
-        g_free(s->vhost_user);
-        s->vhost_user = NULL;
-    }
+    vhost_user_cleanup(&s->vhost_user);
 }
 
 static void vhost_user_blk_instance_init(Object *obj)
diff --git a/hw/scsi/vhost-user-scsi.c b/hw/scsi/vhost-user-scsi.c
index 6728878a52..8b1e6876db 100644
--- a/hw/scsi/vhost-user-scsi.c
+++ b/hw/scsi/vhost-user-scsi.c
@@ -69,7 +69,6 @@ static void vhost_user_scsi_realize(DeviceState *dev, Error **errp)
     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev);
     VHostUserSCSI *s = VHOST_USER_SCSI(dev);
     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s);
-    VhostUserState *user;
     Error *err = NULL;
     int ret;
 
@@ -86,30 +85,24 @@ static void vhost_user_scsi_realize(DeviceState *dev, Error **errp)
         return;
     }
 
-    user = vhost_user_init();
-    if (!user) {
-        error_setg(errp, "vhost-user-scsi: failed to init vhost_user");
+    if (!vhost_user_init(&s->vhost_user, &vs->conf.chardev, errp)) {
         return;
     }
-    user->chr = &vs->conf.chardev;
 
     vsc->dev.nvqs = 2 + vs->conf.num_queues;
     vsc->dev.vqs = g_new(struct vhost_virtqueue, vsc->dev.nvqs);
     vsc->dev.vq_index = 0;
     vsc->dev.backend_features = 0;
 
-    ret = vhost_dev_init(&vsc->dev, user,
+    ret = vhost_dev_init(&vsc->dev, &s->vhost_user,
                          VHOST_BACKEND_TYPE_USER, 0);
     if (ret < 0) {
         error_setg(errp, "vhost-user-scsi: vhost initialization failed: %s",
                    strerror(-ret));
-        vhost_user_cleanup(user);
-        g_free(user);
+        vhost_user_cleanup(&s->vhost_user);
         return;
     }
 
-    s->vhost_user = user;
-
     /* Channel and lun both are 0 for bootable vhost-user-scsi disk */
     vsc->channel = 0;
     vsc->lun = 0;
@@ -130,12 +123,7 @@ static void vhost_user_scsi_unrealize(DeviceState *dev, Error **errp)
     g_free(vqs);
 
     virtio_scsi_common_unrealize(dev, errp);
-
-    if (s->vhost_user) {
-        vhost_user_cleanup(s->vhost_user);
-        g_free(s->vhost_user);
-        s->vhost_user = NULL;
-    }
+    vhost_user_cleanup(&s->vhost_user);
 }
 
 static Property vhost_user_scsi_properties[] = {
diff --git a/hw/virtio/vhost-stub.c b/hw/virtio/vhost-stub.c
index 049089b5e2..c175148fce 100644
--- a/hw/virtio/vhost-stub.c
+++ b/hw/virtio/vhost-stub.c
@@ -7,9 +7,9 @@ bool vhost_has_free_slot(void)
     return true;
 }
 
-VhostUserState *vhost_user_init(void)
+bool vhost_user_init(VhostUserState *user, CharBackend *chr, Error **errp)
 {
-    return NULL;
+    return false;
 }
 
 void vhost_user_cleanup(VhostUserState *user)
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index 0d6c64e5ca..0164060b2b 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -1750,17 +1750,24 @@ static bool vhost_user_mem_section_filter(struct vhost_dev *dev,
     return result;
 }
 
-VhostUserState *vhost_user_init(void)
+bool vhost_user_init(VhostUserState *user, CharBackend *chr, Error **errp)
 {
-    VhostUserState *user = g_new0(struct VhostUserState, 1);
-
-    return user;
+    if (user->chr) {
+        error_setg(errp, "Cannot initialize vhost-user state");
+        return false;
+    }
+    user->chr = chr;
+    return true;
 }
 
 void vhost_user_cleanup(VhostUserState *user)
 {
     int i;
 
+    if (!user->chr) {
+        return;
+    }
+
     for (i = 0; i < VIRTIO_QUEUE_MAX; i++) {
         if (user->notifier[i].addr) {
             object_unparent(OBJECT(&user->notifier[i].mr));
@@ -1768,6 +1775,7 @@ void vhost_user_cleanup(VhostUserState *user)
             user->notifier[i].addr = NULL;
         }
     }
+    user->chr = NULL;
 }
 
 const VhostOps user_ops = {
diff --git a/net/vhost-user.c b/net/vhost-user.c
index cd9659df87..5a26a24708 100644
--- a/net/vhost-user.c
+++ b/net/vhost-user.c
@@ -304,19 +304,14 @@ static int net_vhost_user_init(NetClientState *peer, const char *device,
 {
     Error *err = NULL;
     NetClientState *nc, *nc0 = NULL;
-    VhostUserState *user = NULL;
     NetVhostUserState *s = NULL;
+    VhostUserState *user;
     int i;
 
     assert(name);
     assert(queues > 0);
 
-    user = vhost_user_init();
-    if (!user) {
-        error_report("failed to init vhost_user");
-        goto err;
-    }
-
+    user = g_new0(struct VhostUserState, 1);
     for (i = 0; i < queues; i++) {
         nc = qemu_new_net_client(&net_vhost_user_info, peer, device, name);
         snprintf(nc->info_str, sizeof(nc->info_str), "vhost-user%d to %s",
@@ -325,11 +320,11 @@ static int net_vhost_user_init(NetClientState *peer, const char *device,
         if (!nc0) {
             nc0 = nc;
             s = DO_UPCAST(NetVhostUserState, nc, nc);
-            if (!qemu_chr_fe_init(&s->chr, chr, &err)) {
+            if (!qemu_chr_fe_init(&s->chr, chr, &err) ||
+                !vhost_user_init(user, &s->chr, &err)) {
                 error_report_err(err);
                 goto err;
             }
-            user->chr = &s->chr;
         }
         s = DO_UPCAST(NetVhostUserState, nc, nc);
         s->vhost_user = user;
-- 
2.21.0.4.g36eb1cb9cf

[Qemu-devel] [PATCH v6 04/12] libvhost-user: exit by default on VHOST_USER_NONE

[Marc-André Lureau]

Since commit 2566378d6d13bf4d28c7770bdbda5f7682594bbe, libvhost-user
no longer panics on disconnect (rc == 0), and instead silently ignores
an invalid VHOST_USER_NONE message.

Without extra work from the API user, this will simply busy-loop on
HUP events. The obvious thing to do is to exit(0) instead, while
additional or different work can be done by overriding
iface->process_msg().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Jens Freimann <jfreimann@redhat.com>
---
 contrib/libvhost-user/libvhost-user.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c
index 3f14b4138b..fcf5014240 100644
--- a/contrib/libvhost-user/libvhost-user.c
+++ b/contrib/libvhost-user/libvhost-user.c
@@ -1285,7 +1285,8 @@ vu_process_message(VuDev *dev, VhostUserMsg *vmsg)
     case VHOST_USER_SET_CONFIG:
         return vu_set_config(dev, vmsg);
     case VHOST_USER_NONE:
-        break;
+        /* if you need processing before exit, override iface->process_msg */
+        exit(0);
     case VHOST_USER_POSTCOPY_ADVISE:
         return vu_set_postcopy_advise(dev, vmsg);
     case VHOST_USER_POSTCOPY_LISTEN:
-- 
2.21.0.4.g36eb1cb9cf

[Qemu-devel] [PATCH v6 05/12] vhost-user: wrap some read/write with retry handling

[Marc-André Lureau]

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
 hw/virtio/vhost-user.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index 0164060b2b..3b09c40578 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -968,7 +968,10 @@ static void slave_read(void *opaque)
     iov.iov_base = &hdr;
     iov.iov_len = VHOST_USER_HDR_SIZE;
 
-    size = recvmsg(u->slave_fd, &msgh, 0);
+    do {
+        size = recvmsg(u->slave_fd, &msgh, 0);
+    } while (size < 0 && (errno == EINTR || errno == EAGAIN));
+
     if (size != VHOST_USER_HDR_SIZE) {
         error_report("Failed to read from slave.");
         goto err;
@@ -997,7 +1000,10 @@ static void slave_read(void *opaque)
     }
 
     /* Read payload */
-    size = read(u->slave_fd, &payload, hdr.size);
+    do {
+        size = read(u->slave_fd, &payload, hdr.size);
+    } while (size < 0 && (errno == EINTR || errno == EAGAIN));
+
     if (size != hdr.size) {
         error_report("Failed to read payload from slave.");
         goto err;
@@ -1045,7 +1051,10 @@ static void slave_read(void *opaque)
         iovec[1].iov_base = &payload;
         iovec[1].iov_len = hdr.size;
 
-        size = writev(u->slave_fd, iovec, ARRAY_SIZE(iovec));
+        do {
+            size = writev(u->slave_fd, iovec, ARRAY_SIZE(iovec));
+        } while (size < 0 && (errno == EINTR || errno == EAGAIN));
+
         if (size != VHOST_USER_HDR_SIZE + hdr.size) {
             error_report("Failed to send msg reply to slave.");
             goto err;
-- 
2.21.0.4.g36eb1cb9cf

[Qemu-devel] [PATCH v6 06/12] Add vhost-user-backend

[Marc-André Lureau]

Create a vhost-user-backend object that holds a connection to a
vhost-user backend and can be referenced from virtio devices that
support it. See later patches for input & gpu usage.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 include/sysemu/vhost-user-backend.h |  57 ++++++++
 backends/vhost-user.c               | 209 ++++++++++++++++++++++++++++
 MAINTAINERS                         |   2 +
 backends/Makefile.objs              |   3 +
 4 files changed, 271 insertions(+)
 create mode 100644 include/sysemu/vhost-user-backend.h
 create mode 100644 backends/vhost-user.c

diff --git a/include/sysemu/vhost-user-backend.h b/include/sysemu/vhost-user-backend.h
new file mode 100644
index 0000000000..9abf8f06a1
--- /dev/null
+++ b/include/sysemu/vhost-user-backend.h
@@ -0,0 +1,57 @@
+/*
+ * QEMU vhost-user backend
+ *
+ * Copyright (C) 2018 Red Hat Inc
+ *
+ * Authors:
+ *  Marc-André Lureau <marcandre.lureau@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+#ifndef QEMU_VHOST_USER_BACKEND_H
+#define QEMU_VHOST_USER_BACKEND_H
+
+#include "qom/object.h"
+#include "exec/memory.h"
+#include "qemu/option.h"
+#include "qemu/bitmap.h"
+#include "hw/virtio/vhost.h"
+#include "hw/virtio/vhost-user.h"
+#include "chardev/char-fe.h"
+#include "io/channel.h"
+
+#define TYPE_VHOST_USER_BACKEND "vhost-user-backend"
+#define VHOST_USER_BACKEND(obj) \
+    OBJECT_CHECK(VhostUserBackend, (obj), TYPE_VHOST_USER_BACKEND)
+#define VHOST_USER_BACKEND_GET_CLASS(obj) \
+    OBJECT_GET_CLASS(VhostUserBackendClass, (obj), TYPE_VHOST_USER_BACKEND)
+#define VHOST_USER_BACKEND_CLASS(klass) \
+    OBJECT_CLASS_CHECK(VhostUserBackendClass, (klass), TYPE_VHOST_USER_BACKEND)
+
+typedef struct VhostUserBackend VhostUserBackend;
+typedef struct VhostUserBackendClass VhostUserBackendClass;
+
+struct VhostUserBackendClass {
+    ObjectClass parent_class;
+};
+
+struct VhostUserBackend {
+    /* private */
+    Object parent;
+
+    char *chr_name;
+    CharBackend chr;
+    VhostUserState vhost_user;
+    struct vhost_dev dev;
+    VirtIODevice *vdev;
+    bool started;
+    bool completed;
+};
+
+int vhost_user_backend_dev_init(VhostUserBackend *b, VirtIODevice *vdev,
+                                unsigned nvqs, Error **errp);
+void vhost_user_backend_start(VhostUserBackend *b);
+void vhost_user_backend_stop(VhostUserBackend *b);
+
+#endif
diff --git a/backends/vhost-user.c b/backends/vhost-user.c
new file mode 100644
index 0000000000..2b055544a7
--- /dev/null
+++ b/backends/vhost-user.c
@@ -0,0 +1,209 @@
+/*
+ * QEMU vhost-user backend
+ *
+ * Copyright (C) 2018 Red Hat Inc
+ *
+ * Authors:
+ *  Marc-André Lureau <marcandre.lureau@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+
+#include "qemu/osdep.h"
+#include "hw/qdev.h"
+#include "qapi/error.h"
+#include "qapi/qmp/qerror.h"
+#include "qemu/error-report.h"
+#include "qom/object_interfaces.h"
+#include "sysemu/vhost-user-backend.h"
+#include "sysemu/kvm.h"
+#include "io/channel-command.h"
+#include "hw/virtio/virtio-bus.h"
+
+static bool
+ioeventfd_enabled(void)
+{
+    return kvm_enabled() && kvm_eventfds_enabled();
+}
+
+int
+vhost_user_backend_dev_init(VhostUserBackend *b, VirtIODevice *vdev,
+                            unsigned nvqs, Error **errp)
+{
+    int ret;
+
+    assert(!b->vdev && vdev);
+
+    if (!ioeventfd_enabled()) {
+        error_setg(errp, "vhost initialization failed: requires kvm");
+        return -1;
+    }
+
+    if (!vhost_user_init(&b->vhost_user, &b->chr, errp)) {
+        return -1;
+    }
+
+    b->vdev = vdev;
+    b->dev.nvqs = nvqs;
+    b->dev.vqs = g_new(struct vhost_virtqueue, nvqs);
+
+    ret = vhost_dev_init(&b->dev, &b->vhost_user, VHOST_BACKEND_TYPE_USER, 0);
+    if (ret < 0) {
+        error_setg_errno(errp, -ret, "vhost initialization failed");
+        return -1;
+    }
+
+    return 0;
+}
+
+void
+vhost_user_backend_start(VhostUserBackend *b)
+{
+    BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(b->vdev)));
+    VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+    int ret, i ;
+
+    if (b->started) {
+        return;
+    }
+
+    if (!k->set_guest_notifiers) {
+        error_report("binding does not support guest notifiers");
+        return;
+    }
+
+    ret = vhost_dev_enable_notifiers(&b->dev, b->vdev);
+    if (ret < 0) {
+        return;
+    }
+
+    ret = k->set_guest_notifiers(qbus->parent, b->dev.nvqs, true);
+    if (ret < 0) {
+        error_report("Error binding guest notifier");
+        goto err_host_notifiers;
+    }
+
+    b->dev.acked_features = b->vdev->guest_features;
+    ret = vhost_dev_start(&b->dev, b->vdev);
+    if (ret < 0) {
+        error_report("Error start vhost dev");
+        goto err_guest_notifiers;
+    }
+
+    /* guest_notifier_mask/pending not used yet, so just unmask
+     * everything here.  virtio-pci will do the right thing by
+     * enabling/disabling irqfd.
+     */
+    for (i = 0; i < b->dev.nvqs; i++) {
+        vhost_virtqueue_mask(&b->dev, b->vdev,
+                             b->dev.vq_index + i, false);
+    }
+
+    b->started = true;
+    return;
+
+err_guest_notifiers:
+    k->set_guest_notifiers(qbus->parent, b->dev.nvqs, false);
+err_host_notifiers:
+    vhost_dev_disable_notifiers(&b->dev, b->vdev);
+}
+
+void
+vhost_user_backend_stop(VhostUserBackend *b)
+{
+    BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(b->vdev)));
+    VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+    int ret = 0;
+
+    if (!b->started) {
+        return;
+    }
+
+    vhost_dev_stop(&b->dev, b->vdev);
+
+    if (k->set_guest_notifiers) {
+        ret = k->set_guest_notifiers(qbus->parent,
+                                     b->dev.nvqs, false);
+        if (ret < 0) {
+            error_report("vhost guest notifier cleanup failed: %d", ret);
+        }
+    }
+    assert(ret >= 0);
+
+    vhost_dev_disable_notifiers(&b->dev, b->vdev);
+    b->started = false;
+}
+
+static void set_chardev(Object *obj, const char *value, Error **errp)
+{
+    VhostUserBackend *b = VHOST_USER_BACKEND(obj);
+    Chardev *chr;
+
+    if (b->completed) {
+        error_setg(errp, QERR_PERMISSION_DENIED);
+        return;
+    }
+
+    g_free(b->chr_name);
+    b->chr_name = g_strdup(value);
+
+    chr = qemu_chr_find(b->chr_name);
+    if (chr == NULL) {
+        error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
+                  "Chardev '%s' not found", b->chr_name);
+        return;
+    }
+
+    if (!qemu_chr_fe_init(&b->chr, chr, errp)) {
+        return;
+    }
+
+    b->completed = true;
+    /* could call vhost_dev_init() so early message can be exchanged */
+}
+
+static char *get_chardev(Object *obj, Error **errp)
+{
+    VhostUserBackend *b = VHOST_USER_BACKEND(obj);
+    Chardev *chr = qemu_chr_fe_get_driver(&b->chr);
+
+    if (chr && chr->label) {
+        return g_strdup(chr->label);
+    }
+
+    return NULL;
+}
+
+static void vhost_user_backend_init(Object *obj)
+{
+    object_property_add_str(obj, "chardev", get_chardev, set_chardev, NULL);
+}
+
+static void vhost_user_backend_finalize(Object *obj)
+{
+    VhostUserBackend *b = VHOST_USER_BACKEND(obj);
+
+    g_free(b->dev.vqs);
+    g_free(b->chr_name);
+
+    vhost_user_cleanup(&b->vhost_user);
+    qemu_chr_fe_deinit(&b->chr, true);
+}
+
+static const TypeInfo vhost_user_backend_info = {
+    .name = TYPE_VHOST_USER_BACKEND,
+    .parent = TYPE_OBJECT,
+    .instance_size = sizeof(VhostUserBackend),
+    .instance_init = vhost_user_backend_init,
+    .instance_finalize = vhost_user_backend_finalize,
+    .class_size = sizeof(VhostUserBackendClass),
+};
+
+static void register_types(void)
+{
+    type_register_static(&vhost_user_backend_info);
+}
+
+type_init(register_types);
diff --git a/MAINTAINERS b/MAINTAINERS
index d811c968ee..12e9bf6cdc 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1454,6 +1454,8 @@ F: hw/*/*vhost*
 F: docs/interop/vhost-user.json
 F: docs/interop/vhost-user.txt
 F: contrib/vhost-user-*/
+F: backends/vhost-user.c
+F: include/sysemu/vhost-user-backend.h
 
 virtio
 M: Michael S. Tsirkin <mst@redhat.com>
diff --git a/backends/Makefile.objs b/backends/Makefile.objs
index ff619d31b4..99c14c57b5 100644
--- a/backends/Makefile.objs
+++ b/backends/Makefile.objs
@@ -11,7 +11,10 @@ common-obj-y += cryptodev-builtin.o
 
 ifeq ($(CONFIG_VIRTIO_CRYPTO),y)
 common-obj-y += cryptodev-vhost.o
+
 common-obj-$(CONFIG_VHOST_CRYPTO) += cryptodev-vhost-user.o
 endif
 
+common-obj-$(call land,$(CONFIG_VHOST_USER),$(CONFIG_LINUX)) += vhost-user.o
+
 common-obj-$(CONFIG_LINUX) += hostmem-memfd.o
-- 
2.21.0.4.g36eb1cb9cf

[Qemu-devel] [PATCH v6 07/12] vhost-user: split vhost_user_read()

[Marc-André Lureau]

Split vhost_user_read(), so only header can be read with
vhost_user_read_header().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
---
 hw/virtio/vhost-user.c | 27 +++++++++++++++++++--------
 1 file changed, 19 insertions(+), 8 deletions(-)

diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index 3b09c40578..5df73405bc 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -214,7 +214,7 @@ static bool ioeventfd_enabled(void)
     return !kvm_enabled() || kvm_eventfds_enabled();
 }
 
-static int vhost_user_read(struct vhost_dev *dev, VhostUserMsg *msg)
+static int vhost_user_read_header(struct vhost_dev *dev, VhostUserMsg *msg)
 {
     struct vhost_user *u = dev->opaque;
     CharBackend *chr = u->user->chr;
@@ -225,7 +225,7 @@ static int vhost_user_read(struct vhost_dev *dev, VhostUserMsg *msg)
     if (r != size) {
         error_report("Failed to read msg header. Read %d instead of %d."
                      " Original request %d.", r, size, msg->hdr.request);
-        goto fail;
+        return -1;
     }
 
     /* validate received flags */
@@ -233,7 +233,21 @@ static int vhost_user_read(struct vhost_dev *dev, VhostUserMsg *msg)
         error_report("Failed to read msg header."
                 " Flags 0x%x instead of 0x%x.", msg->hdr.flags,
                 VHOST_USER_REPLY_MASK | VHOST_USER_VERSION);
-        goto fail;
+        return -1;
+    }
+
+    return 0;
+}
+
+static int vhost_user_read(struct vhost_dev *dev, VhostUserMsg *msg)
+{
+    struct vhost_user *u = dev->opaque;
+    CharBackend *chr = u->user->chr;
+    uint8_t *p = (uint8_t *) msg;
+    int r, size;
+
+    if (vhost_user_read_header(dev, msg) < 0) {
+        return -1;
     }
 
     /* validate message size is sane */
@@ -241,7 +255,7 @@ static int vhost_user_read(struct vhost_dev *dev, VhostUserMsg *msg)
         error_report("Failed to read msg header."
                 " Size %d exceeds the maximum %zu.", msg->hdr.size,
                 VHOST_USER_PAYLOAD_SIZE);
-        goto fail;
+        return -1;
     }
 
     if (msg->hdr.size) {
@@ -251,14 +265,11 @@ static int vhost_user_read(struct vhost_dev *dev, VhostUserMsg *msg)
         if (r != size) {
             error_report("Failed to read msg payload."
                          " Read %d instead of %d.", r, msg->hdr.size);
-            goto fail;
+            return -1;
         }
     }
 
     return 0;
-
-fail:
-    return -1;
 }
 
 static int process_message_reply(struct vhost_dev *dev,
-- 
2.21.0.4.g36eb1cb9cf

[Qemu-devel] [PATCH v6 08/12] vhost-user: add vhost_user_input_get_config()

[Marc-André Lureau]

Ask vhost user input backend the list of virtio_input_config.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
---
 contrib/libvhost-user/libvhost-user.h |  1 +
 include/hw/virtio/vhost-backend.h     |  4 ++
 hw/virtio/vhost-user.c                | 60 +++++++++++++++++++++++++++
 docs/interop/vhost-user.txt           |  8 ++++
 4 files changed, 73 insertions(+)

diff --git a/contrib/libvhost-user/libvhost-user.h b/contrib/libvhost-user/libvhost-user.h
index c0133b7f3f..b0c798fa1a 100644
--- a/contrib/libvhost-user/libvhost-user.h
+++ b/contrib/libvhost-user/libvhost-user.h
@@ -91,6 +91,7 @@ typedef enum VhostUserRequest {
     VHOST_USER_POSTCOPY_ADVISE  = 28,
     VHOST_USER_POSTCOPY_LISTEN  = 29,
     VHOST_USER_POSTCOPY_END     = 30,
+    VHOST_USER_INPUT_GET_CONFIG = 31,
     VHOST_USER_MAX
 } VhostUserRequest;
 
diff --git a/include/hw/virtio/vhost-backend.h b/include/hw/virtio/vhost-backend.h
index 81283ec50f..1fca321d8a 100644
--- a/include/hw/virtio/vhost-backend.h
+++ b/include/hw/virtio/vhost-backend.h
@@ -12,6 +12,7 @@
 #define VHOST_BACKEND_H
 
 #include "exec/memory.h"
+#include "standard-headers/linux/virtio_input.h"
 
 typedef enum VhostBackendType {
     VHOST_BACKEND_TYPE_NONE = 0,
@@ -160,4 +161,7 @@ int vhost_backend_invalidate_device_iotlb(struct vhost_dev *dev,
 int vhost_backend_handle_iotlb_msg(struct vhost_dev *dev,
                                           struct vhost_iotlb_msg *imsg);
 
+int vhost_user_input_get_config(struct vhost_dev *dev,
+                                struct virtio_input_config **config);
+
 #endif /* VHOST_BACKEND_H */
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index 5df73405bc..cf3fd39035 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -93,6 +93,7 @@ typedef enum VhostUserRequest {
     VHOST_USER_POSTCOPY_ADVISE  = 28,
     VHOST_USER_POSTCOPY_LISTEN  = 29,
     VHOST_USER_POSTCOPY_END     = 30,
+    VHOST_USER_INPUT_GET_CONFIG = 31,
     VHOST_USER_MAX
 } VhostUserRequest;
 
@@ -342,6 +343,65 @@ static int vhost_user_write(struct vhost_dev *dev, VhostUserMsg *msg,
     return 0;
 }
 
+static void *vhost_user_read_size(struct vhost_dev *dev, uint32_t size)
+{
+    struct vhost_user *u = dev->opaque;
+    CharBackend *chr = u->user->chr;
+    int r;
+    uint8_t *p = g_malloc(size);
+
+    r = qemu_chr_fe_read_all(chr, p, size);
+    if (r != size) {
+        error_report("Failed to read msg payload."
+                     " Read %d instead of %u.", r, size);
+        g_free(p);
+        return NULL;
+    }
+
+    return p;
+}
+
+int vhost_user_input_get_config(struct vhost_dev *dev,
+                                struct virtio_input_config **config)
+{
+    void *p = NULL;
+    VhostUserMsg msg = {
+        .hdr.request = VHOST_USER_INPUT_GET_CONFIG,
+        .hdr.flags = VHOST_USER_VERSION,
+    };
+
+    if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
+        goto err;
+    }
+
+    if (vhost_user_read_header(dev, &msg) < 0) {
+        goto err;
+    }
+
+    if (msg.hdr.request != VHOST_USER_INPUT_GET_CONFIG) {
+        error_report("Received unexpected msg type. Expected %d received %d",
+                     VHOST_USER_INPUT_GET_CONFIG, msg.hdr.request);
+        goto err;
+    }
+
+    if (msg.hdr.size % sizeof(struct virtio_input_config)) {
+        error_report("Invalid msg size");
+        goto err;
+    }
+
+    p = vhost_user_read_size(dev, msg.hdr.size);
+    if (!p) {
+        goto err;
+    }
+
+    *config = p;
+    return msg.hdr.size / sizeof(struct virtio_input_config);
+
+err:
+    g_free(p);
+    return -1;
+}
+
 static int vhost_user_set_log_base(struct vhost_dev *dev, uint64_t base,
                                    struct vhost_log *log)
 {
diff --git a/docs/interop/vhost-user.txt b/docs/interop/vhost-user.txt
index 9ee2a60cfb..e145b3ec55 100644
--- a/docs/interop/vhost-user.txt
+++ b/docs/interop/vhost-user.txt
@@ -766,6 +766,14 @@ Master message types
       was previously sent.
       The value returned is an error indication; 0 is success.
 
+ * VHOST_USER_INPUT_GET_CONFIG
+      Id: 31
+      Master payload: N/A
+      Slave payload: (struct virtio_input_config)*
+
+      Ask vhost user input backend the list of virtio_input_config, in
+      host endianness.
+
 Slave message types
 -------------------
 
-- 
2.21.0.4.g36eb1cb9cf

[Qemu-devel] [PATCH v6 09/12] libvhost-user-glib: export vug_source_new()

[Marc-André Lureau]

Simplify the creation of FD sources for other users. This is just
convenience to avoid duplicating similar code elsewhere.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 contrib/libvhost-user/libvhost-user-glib.h |  3 +++
 contrib/libvhost-user/libvhost-user-glib.c | 11 ++++++-----
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/contrib/libvhost-user/libvhost-user-glib.h b/contrib/libvhost-user/libvhost-user-glib.h
index 6b2110b94c..d3200f3afc 100644
--- a/contrib/libvhost-user/libvhost-user-glib.h
+++ b/contrib/libvhost-user/libvhost-user-glib.h
@@ -29,4 +29,7 @@ void vug_init(VugDev *dev, int socket,
               vu_panic_cb panic, const VuDevIface *iface);
 void vug_deinit(VugDev *dev);
 
+GSource *vug_source_new(VugDev *dev, int fd, GIOCondition cond,
+                        vu_watch_cb vu_cb, gpointer data);
+
 #endif /* LIBVHOST_USER_GLIB_H */
diff --git a/contrib/libvhost-user/libvhost-user-glib.c b/contrib/libvhost-user/libvhost-user-glib.c
index 545f089587..42660a1b36 100644
--- a/contrib/libvhost-user/libvhost-user-glib.c
+++ b/contrib/libvhost-user/libvhost-user-glib.c
@@ -68,15 +68,16 @@ static GSourceFuncs vug_src_funcs = {
     NULL
 };
 
-static GSource *
-vug_source_new(VuDev *dev, int fd, GIOCondition cond,
+GSource *
+vug_source_new(VugDev *gdev, int fd, GIOCondition cond,
                vu_watch_cb vu_cb, gpointer data)
 {
+    VuDev *dev = &gdev->parent;
     GSource *gsrc;
     VugSrc *src;
     guint id;
 
-    g_assert(dev);
+    g_assert(gdev);
     g_assert(fd >= 0);
     g_assert(vu_cb);
 
@@ -106,7 +107,7 @@ set_watch(VuDev *vu_dev, int fd, int vu_evt, vu_watch_cb cb, void *pvt)
     g_assert(cb);
 
     dev = container_of(vu_dev, VugDev, parent);
-    src = vug_source_new(vu_dev, fd, vu_evt, cb, pvt);
+    src = vug_source_new(dev, fd, vu_evt, cb, pvt);
     g_hash_table_replace(dev->fdmap, GINT_TO_POINTER(fd), src);
 }
 
@@ -141,7 +142,7 @@ vug_init(VugDev *dev, int socket,
     dev->fdmap = g_hash_table_new_full(NULL, NULL, NULL,
                                        (GDestroyNotify) g_source_destroy);
 
-    dev->src = vug_source_new(&dev->parent, socket, G_IO_IN, vug_watch, NULL);
+    dev->src = vug_source_new(dev, socket, G_IO_IN, vug_watch, NULL);
 }
 
 void
-- 
2.21.0.4.g36eb1cb9cf

[Qemu-devel] [PATCH v6 10/12] libvhost-user: add vu_queue_unpop()

[Marc-André Lureau]

vhost-user-input will make use of this function to undo some queue pop
in case the virtio queue does not have enough room.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 contrib/libvhost-user/libvhost-user.h | 14 ++++++++++++++
 contrib/libvhost-user/libvhost-user.c | 16 ++++++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/contrib/libvhost-user/libvhost-user.h b/contrib/libvhost-user/libvhost-user.h
index b0c798fa1a..01738bf44a 100644
--- a/contrib/libvhost-user/libvhost-user.h
+++ b/contrib/libvhost-user/libvhost-user.h
@@ -459,6 +459,20 @@ void vu_queue_notify(VuDev *dev, VuVirtq *vq);
  */
 void *vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz);
 
+
+/**
+ * vu_queue_unpop:
+ * @dev: a VuDev context
+ * @vq: a VuVirtq queue
+ * @elem: The #VuVirtqElement
+ * @len: number of bytes written
+ *
+ * Pretend the most recent element wasn't popped from the virtqueue.  The next
+ * call to vu_queue_pop() will refetch the element.
+ */
+void vu_queue_unpop(VuDev *dev, VuVirtq *vq, VuVirtqElement *elem,
+                    size_t len);
+
 /**
  * vu_queue_rewind:
  * @dev: a VuDev context
diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c
index fcf5014240..df72d3e440 100644
--- a/contrib/libvhost-user/libvhost-user.c
+++ b/contrib/libvhost-user/libvhost-user.c
@@ -1966,6 +1966,22 @@ vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz)
     return elem;
 }
 
+static void
+vu_queue_detach_element(VuDev *dev, VuVirtq *vq, VuVirtqElement *elem,
+                        size_t len)
+{
+    vq->inuse--;
+    /* unmap, when DMA support is added */
+}
+
+void
+vu_queue_unpop(VuDev *dev, VuVirtq *vq, VuVirtqElement *elem,
+               size_t len)
+{
+    vq->last_avail_idx--;
+    vu_queue_detach_element(dev, vq, elem, len);
+}
+
 bool
 vu_queue_rewind(VuDev *dev, VuVirtq *vq, unsigned int num)
 {
-- 
2.21.0.4.g36eb1cb9cf

[Qemu-devel] [PATCH v6 11/12] Add vhost-user-input-pci

[Marc-André Lureau]

Add a new virtio-input device, which connects to a vhost-user
backend.

vhost-user-input is similar to virtio-input-host, it is wrapped by
vhost-user-input-pci. Instead of reading configuration directly from
an input device / evdev, it reads it over vhost-user protocol with
INPUT_GET_CONFIG message. Then vhost-user-backend takes care of
interfacing the virtio device with the backend, for the queue & events
processing.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
---
 include/hw/virtio/virtio-input.h | 14 +++++
 hw/input/vhost-user-input.c      | 99 ++++++++++++++++++++++++++++++++
 hw/virtio/vhost-user-input-pci.c | 53 +++++++++++++++++
 MAINTAINERS                      |  1 +
 hw/input/Kconfig                 |  5 ++
 hw/input/Makefile.objs           |  1 +
 hw/virtio/Makefile.objs          |  1 +
 7 files changed, 174 insertions(+)
 create mode 100644 hw/input/vhost-user-input.c
 create mode 100644 hw/virtio/vhost-user-input-pci.c

diff --git a/include/hw/virtio/virtio-input.h b/include/hw/virtio/virtio-input.h
index 054c38836f..4fca03e796 100644
--- a/include/hw/virtio/virtio-input.h
+++ b/include/hw/virtio/virtio-input.h
@@ -2,6 +2,7 @@
 #define QEMU_VIRTIO_INPUT_H
 
 #include "ui/input.h"
+#include "sysemu/vhost-user-backend.h"
 
 /* ----------------------------------------------------------------- */
 /* virtio input protocol                                             */
@@ -42,11 +43,18 @@ typedef struct virtio_input_event virtio_input_event;
 #define VIRTIO_INPUT_HOST_GET_PARENT_CLASS(obj) \
         OBJECT_GET_PARENT_CLASS(obj, TYPE_VIRTIO_INPUT_HOST)
 
+#define TYPE_VHOST_USER_INPUT   "vhost-user-input"
+#define VHOST_USER_INPUT(obj)                              \
+    OBJECT_CHECK(VHostUserInput, (obj), TYPE_VHOST_USER_INPUT)
+#define VHOST_USER_INPUT_GET_PARENT_CLASS(obj)             \
+    OBJECT_GET_PARENT_CLASS(obj, TYPE_VHOST_USER_INPUT)
+
 typedef struct VirtIOInput VirtIOInput;
 typedef struct VirtIOInputClass VirtIOInputClass;
 typedef struct VirtIOInputConfig VirtIOInputConfig;
 typedef struct VirtIOInputHID VirtIOInputHID;
 typedef struct VirtIOInputHost VirtIOInputHost;
+typedef struct VHostUserInput VHostUserInput;
 
 struct VirtIOInputConfig {
     virtio_input_config               config;
@@ -98,6 +106,12 @@ struct VirtIOInputHost {
     int                               fd;
 };
 
+struct VHostUserInput {
+    VirtIOInput                       parent_obj;
+
+    VhostUserBackend                  *vhost;
+};
+
 void virtio_input_send(VirtIOInput *vinput, virtio_input_event *event);
 void virtio_input_init_config(VirtIOInput *vinput,
                               virtio_input_config *config);
diff --git a/hw/input/vhost-user-input.c b/hw/input/vhost-user-input.c
new file mode 100644
index 0000000000..41c25d2398
--- /dev/null
+++ b/hw/input/vhost-user-input.c
@@ -0,0 +1,99 @@
+/*
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * (at your option) any later version.  See the COPYING file in the
+ * top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "qemu-common.h"
+
+#include "hw/qdev.h"
+#include "hw/virtio/virtio-input.h"
+
+static void vhost_input_realize(DeviceState *dev, Error **errp)
+{
+    VHostUserInput *vhi = VHOST_USER_INPUT(dev);
+    VirtIOInput *vinput = VIRTIO_INPUT(dev);
+    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+    virtio_input_config *config;
+    int i, ret;
+
+    if (vhost_user_backend_dev_init(vhi->vhost, vdev, 2, errp) == -1) {
+        return;
+    }
+
+    ret = vhost_user_input_get_config(&vhi->vhost->dev, &config);
+    if (ret < 0) {
+        error_setg(errp, "failed to get input config");
+        return;
+    }
+    for (i = 0; i < ret; i++) {
+        virtio_input_add_config(vinput, &config[i]);
+    }
+    g_free(config);
+}
+
+static void vhost_input_change_active(VirtIOInput *vinput)
+{
+    VHostUserInput *vhi = VHOST_USER_INPUT(vinput);
+
+    if (vinput->active) {
+        vhost_user_backend_start(vhi->vhost);
+    } else {
+        vhost_user_backend_stop(vhi->vhost);
+    }
+}
+
+static const VMStateDescription vmstate_vhost_input = {
+    .name = "vhost-user-input",
+    .unmigratable = 1,
+};
+
+static void vhost_input_class_init(ObjectClass *klass, void *data)
+{
+    VirtIOInputClass *vic = VIRTIO_INPUT_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->vmsd           = &vmstate_vhost_input;
+    vic->realize       = vhost_input_realize;
+    vic->change_active = vhost_input_change_active;
+}
+
+static void vhost_input_init(Object *obj)
+{
+    VHostUserInput *vhi = VHOST_USER_INPUT(obj);
+    VirtIOInput *vinput = VIRTIO_INPUT(obj);
+    struct virtio_input_config vhost_input_config[] = { { /* empty list */ } };
+
+    virtio_input_init_config(vinput, vhost_input_config);
+
+    vhi->vhost = VHOST_USER_BACKEND(object_new(TYPE_VHOST_USER_BACKEND));
+    object_property_add_alias(obj, "chardev",
+                              OBJECT(vhi->vhost), "chardev", &error_abort);
+}
+
+static void vhost_input_finalize(Object *obj)
+{
+    VHostUserInput *vhi = VHOST_USER_INPUT(obj);
+
+    object_unref(OBJECT(vhi->vhost));
+}
+
+static const TypeInfo vhost_input_info = {
+    .name          = TYPE_VHOST_USER_INPUT,
+    .parent        = TYPE_VIRTIO_INPUT,
+    .instance_size = sizeof(VHostUserInput),
+    .instance_init = vhost_input_init,
+    .instance_finalize = vhost_input_finalize,
+    .class_init    = vhost_input_class_init,
+};
+
+/* ----------------------------------------------------------------- */
+
+static void vhost_input_register_types(void)
+{
+    type_register_static(&vhost_input_info);
+}
+
+type_init(vhost_input_register_types)
diff --git a/hw/virtio/vhost-user-input-pci.c b/hw/virtio/vhost-user-input-pci.c
new file mode 100644
index 0000000000..3d1b7a85fd
--- /dev/null
+++ b/hw/virtio/vhost-user-input-pci.c
@@ -0,0 +1,53 @@
+/*
+ * This work is licensed under the terms of the GNU LGPL, version 2 or
+ * later.  See the COPYING.LIB file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+
+#include "hw/virtio/virtio.h"
+#include "hw/virtio/virtio-input.h"
+#include "qapi/error.h"
+#include "qemu/error-report.h"
+#include "virtio-pci.h"
+
+typedef struct VHostUserInputPCI VHostUserInputPCI;
+
+#define TYPE_VHOST_USER_INPUT_PCI "vhost-user-input-pci-base"
+
+#define VHOST_USER_INPUT_PCI(obj) \
+    OBJECT_CHECK(VHostUserInputPCI, (obj), TYPE_VHOST_USER_INPUT_PCI)
+
+struct VHostUserInputPCI {
+    VirtIOPCIProxy parent_obj;
+    VHostUserInput vhi;
+};
+
+static void vhost_user_input_pci_instance_init(Object *obj)
+{
+    VHostUserInputPCI *dev = VHOST_USER_INPUT_PCI(obj);
+
+    virtio_instance_init_common(obj, &dev->vhi, sizeof(dev->vhi),
+                                TYPE_VHOST_USER_INPUT);
+
+    object_property_add_alias(obj, "chardev",
+                              OBJECT(&dev->vhi), "chardev",
+                              &error_abort);
+}
+
+static const VirtioPCIDeviceTypeInfo vhost_user_input_pci_info = {
+    .base_name = TYPE_VHOST_USER_INPUT_PCI,
+    .generic_name = "vhost-user-input-pci",
+    .transitional_name = "vhost-user-input-pci-transitional",
+    .non_transitional_name = "vhost-user-input-pci-non-transitional",
+    .parent = TYPE_VIRTIO_INPUT_PCI,
+    .instance_size = sizeof(VHostUserInputPCI),
+    .instance_init = vhost_user_input_pci_instance_init,
+};
+
+static void vhost_user_input_pci_register(void)
+{
+    virtio_pci_types_register(&vhost_user_input_pci_info);
+}
+
+type_init(vhost_user_input_pci_register)
diff --git a/MAINTAINERS b/MAINTAINERS
index 12e9bf6cdc..a601b97adb 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1497,6 +1497,7 @@ L: qemu-s390x@nongnu.org
 virtio-input
 M: Gerd Hoffmann <kraxel@redhat.com>
 S: Maintained
+F: hw/input/vhost-user-input.c
 F: hw/input/virtio-input*.c
 F: include/hw/virtio/virtio-input.h
 
diff --git a/hw/input/Kconfig b/hw/input/Kconfig
index e2e66f0858..50e55e3538 100644
--- a/hw/input/Kconfig
+++ b/hw/input/Kconfig
@@ -29,5 +29,10 @@ config VIRTIO_INPUT_HOST
     default y
     depends on VIRTIO && LINUX
 
+config VHOST_USER_INPUT
+    bool
+    default y
+    depends on VIRTIO_INPUT && VHOST_USER
+
 config TSC210X
     bool
diff --git a/hw/input/Makefile.objs b/hw/input/Makefile.objs
index c8b00f71ec..9511e3102f 100644
--- a/hw/input/Makefile.objs
+++ b/hw/input/Makefile.objs
@@ -11,6 +11,7 @@ common-obj-$(CONFIG_VIRTIO_INPUT) += virtio-input.o
 common-obj-$(CONFIG_VIRTIO_INPUT) += virtio-input-hid.o
 ifeq ($(CONFIG_LINUX),y)
 common-obj-$(CONFIG_VIRTIO_INPUT) += virtio-input-host.o
+common-obj-$(CONFIG_VHOST_USER_INPUT) += vhost-user-input.o
 endif
 
 obj-$(CONFIG_MILKYMIST) += milkymist-softusb.o
diff --git a/hw/virtio/Makefile.objs b/hw/virtio/Makefile.objs
index f2ab667a21..5570ea8df8 100644
--- a/hw/virtio/Makefile.objs
+++ b/hw/virtio/Makefile.objs
@@ -17,6 +17,7 @@ obj-$(CONFIG_VHOST_VSOCK) += vhost-vsock.o
 ifeq ($(CONFIG_VIRTIO_PCI),y)
 obj-$(CONFIG_VHOST_VSOCK) += vhost-vsock-pci.o
 obj-$(CONFIG_VHOST_USER_BLK) += vhost-user-blk-pci.o
+obj-$(CONFIG_VHOST_USER_INPUT) += vhost-user-input-pci.o
 obj-$(CONFIG_VHOST_USER_SCSI) += vhost-user-scsi-pci.o
 obj-$(CONFIG_VHOST_SCSI) += vhost-scsi-pci.o
 obj-$(CONFIG_VIRTIO_INPUT_HOST) += virtio-input-host-pci.o
-- 
2.21.0.4.g36eb1cb9cf

[Qemu-devel] [PATCH v6 12/12] contrib: add vhost-user-input

[Marc-André Lureau]

Add a vhost-user input backend example, based on virtio-input-host
device. It takes an evdev path as argument, and can be associated with
a vhost-user-input device via a UNIX socket:

$ vhost-user-input -p /dev/input/eventX -s /tmp/vui.sock

$ qemu ... -chardev socket,id=vuic,path=/tmp/vui.sock
  -device vhost-user-input-pci,chardev=vuic

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
---
 contrib/vhost-user-input/main.c        | 398 +++++++++++++++++++++++++
 MAINTAINERS                            |   1 +
 Makefile                               |   3 +
 Makefile.objs                          |   1 +
 configure                              |   3 +
 contrib/vhost-user-input/Makefile.objs |   1 +
 6 files changed, 407 insertions(+)
 create mode 100644 contrib/vhost-user-input/main.c
 create mode 100644 contrib/vhost-user-input/Makefile.objs

diff --git a/contrib/vhost-user-input/main.c b/contrib/vhost-user-input/main.c
new file mode 100644
index 0000000000..bef44f163d
--- /dev/null
+++ b/contrib/vhost-user-input/main.c
@@ -0,0 +1,398 @@
+/*
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * (at your option) any later version.  See the COPYING file in the
+ * top-level directory.
+ */
+
+#include "qemu/osdep.h"
+
+#include <glib.h>
+#include <linux/input.h>
+
+#include "qemu/iov.h"
+#include "qemu/bswap.h"
+#include "contrib/libvhost-user/libvhost-user.h"
+#include "contrib/libvhost-user/libvhost-user-glib.h"
+#include "standard-headers/linux/virtio_input.h"
+#include "qapi/error.h"
+
+typedef struct virtio_input_event virtio_input_event;
+typedef struct virtio_input_config virtio_input_config;
+
+typedef struct VuInput {
+    VugDev dev;
+    GSource *evsrc;
+    int evdevfd;
+    GArray *config;
+    struct {
+        virtio_input_event event;
+        VuVirtqElement *elem;
+    }                                 *queue;
+    uint32_t qindex, qsize;
+} VuInput;
+
+static void vi_input_send(VuInput *vi, struct virtio_input_event *event)
+{
+    VuDev *dev = &vi->dev.parent;
+    VuVirtq *vq = vu_get_queue(dev, 0);
+    VuVirtqElement *elem;
+    int i, len;
+
+    /* queue up events ... */
+    if (vi->qindex == vi->qsize) {
+        vi->qsize++;
+        vi->queue = g_realloc_n(vi->queue, vi->qsize, sizeof(vi->queue[0]));
+    }
+    vi->queue[vi->qindex++].event = *event;
+
+    /* ... until we see a report sync ... */
+    if (event->type != htole16(EV_SYN) ||
+        event->code != htole16(SYN_REPORT)) {
+        return;
+    }
+
+    /* ... then check available space ... */
+    for (i = 0; i < vi->qindex; i++) {
+        elem = vu_queue_pop(dev, vq, sizeof(VuVirtqElement));
+        if (!elem) {
+            while (--i >= 0) {
+                vu_queue_unpop(dev, vq, vi->queue[i].elem, 0);
+            }
+            vi->qindex = 0;
+            g_warning("virtio-input queue full");
+            return;
+        }
+        vi->queue[i].elem = elem;
+    }
+
+    /* ... and finally pass them to the guest */
+    for (i = 0; i < vi->qindex; i++) {
+        elem = vi->queue[i].elem;
+        len = iov_from_buf(elem->in_sg, elem->in_num,
+                           0, &vi->queue[i].event, sizeof(virtio_input_event));
+        vu_queue_push(dev, vq, elem, len);
+        g_free(elem);
+    }
+
+    vu_queue_notify(&vi->dev.parent, vq);
+    vi->qindex = 0;
+}
+
+static void
+vi_evdev_watch(VuDev *dev, int condition, void *data)
+{
+    VuInput *vi = data;
+    int fd = vi->evdevfd;
+
+    g_debug("Got evdev condition %x", condition);
+
+    struct virtio_input_event virtio;
+    struct input_event evdev;
+    int rc;
+
+    for (;;) {
+        rc = read(fd, &evdev, sizeof(evdev));
+        if (rc != sizeof(evdev)) {
+            break;
+        }
+
+        g_debug("input %d %d %d", evdev.type, evdev.code, evdev.value);
+
+        virtio.type  = htole16(evdev.type);
+        virtio.code  = htole16(evdev.code);
+        virtio.value = htole32(evdev.value);
+        vi_input_send(vi, &virtio);
+    }
+}
+
+
+static void vi_handle_status(VuInput *vi, virtio_input_event *event)
+{
+    struct input_event evdev;
+    int rc;
+
+    if (gettimeofday(&evdev.time, NULL)) {
+        perror("vi_handle_status: gettimeofday");
+        return;
+    }
+
+    evdev.type = le16toh(event->type);
+    evdev.code = le16toh(event->code);
+    evdev.value = le32toh(event->value);
+
+    rc = write(vi->evdevfd, &evdev, sizeof(evdev));
+    if (rc == -1) {
+        perror("vi_host_handle_status: write");
+    }
+}
+
+static void vi_handle_sts(VuDev *dev, int qidx)
+{
+    VuInput *vi = container_of(dev, VuInput, dev.parent);
+    VuVirtq *vq = vu_get_queue(dev, qidx);
+    virtio_input_event event;
+    VuVirtqElement *elem;
+    int len;
+
+    g_debug("%s", G_STRFUNC);
+
+    for (;;) {
+        elem = vu_queue_pop(dev, vq, sizeof(VuVirtqElement));
+        if (!elem) {
+            break;
+        }
+
+        memset(&event, 0, sizeof(event));
+        len = iov_to_buf(elem->out_sg, elem->out_num,
+                         0, &event, sizeof(event));
+        vi_handle_status(vi, &event);
+        vu_queue_push(dev, vq, elem, len);
+        g_free(elem);
+    }
+
+    vu_queue_notify(&vi->dev.parent, vq);
+}
+
+static void
+vi_panic(VuDev *dev, const char *msg)
+{
+    g_critical("%s\n", msg);
+    exit(EXIT_FAILURE);
+}
+
+static void
+vi_queue_set_started(VuDev *dev, int qidx, bool started)
+{
+    VuInput *vi = container_of(dev, VuInput, dev.parent);
+    VuVirtq *vq = vu_get_queue(dev, qidx);
+
+    g_debug("queue started %d:%d", qidx, started);
+
+    if (qidx == 1) {
+        vu_set_queue_handler(dev, vq, started ? vi_handle_sts : NULL);
+    }
+
+    started = vu_queue_started(dev, vu_get_queue(dev, 0)) &&
+        vu_queue_started(dev, vu_get_queue(dev, 1));
+
+    if (started && !vi->evsrc) {
+        vi->evsrc = vug_source_new(&vi->dev, vi->evdevfd,
+                                   G_IO_IN, vi_evdev_watch, vi);
+    }
+
+    if (!started && vi->evsrc) {
+        g_source_destroy(vi->evsrc);
+        vi->evsrc = NULL;
+    }
+}
+
+static int
+vi_process_msg(VuDev *dev, VhostUserMsg *vmsg, int *do_reply)
+{
+    VuInput *vi = container_of(dev, VuInput, dev.parent);
+
+    switch (vmsg->request) {
+    case VHOST_USER_INPUT_GET_CONFIG:
+        vmsg->size = vi->config->len * sizeof(virtio_input_config);
+        vmsg->data = g_memdup(vi->config->data, vmsg->size);
+        *do_reply = true;
+        return 1;
+    default:
+        return 0;
+    }
+}
+
+static const VuDevIface vuiface = {
+    .queue_set_started = vi_queue_set_started,
+    .process_msg = vi_process_msg,
+};
+
+static void
+vi_bits_config(VuInput *vi, int type, int count)
+{
+    virtio_input_config bits;
+    int rc, i, size = 0;
+
+    memset(&bits, 0, sizeof(bits));
+    rc = ioctl(vi->evdevfd, EVIOCGBIT(type, count / 8), bits.u.bitmap);
+    if (rc < 0) {
+        return;
+    }
+
+    for (i = 0; i < count / 8; i++) {
+        if (bits.u.bitmap[i]) {
+            size = i + 1;
+        }
+    }
+    if (size == 0) {
+        return;
+    }
+
+    bits.select = VIRTIO_INPUT_CFG_EV_BITS;
+    bits.subsel = type;
+    bits.size   = size;
+    g_array_append_val(vi->config, bits);
+}
+
+static int unix_sock_new(char *path)
+{
+    int sock;
+    struct sockaddr_un un;
+    size_t len;
+
+    sock = socket(AF_UNIX, SOCK_STREAM, 0);
+    if (sock <= 0) {
+        perror("socket");
+        return -1;
+    }
+
+    un.sun_family = AF_UNIX;
+    snprintf(un.sun_path, sizeof(un.sun_path), "%s", path);
+    len = sizeof(un.sun_family) + strlen(un.sun_path);
+
+    unlink(path);
+    if (bind(sock, (struct sockaddr *)&un, len) < 0) {
+        perror("bind");
+        goto fail;
+    }
+
+    if (listen(sock, 1) < 0) {
+        perror("listen");
+        goto fail;
+    }
+
+    return sock;
+
+fail:
+    close(sock);
+
+    return -1;
+}
+
+static char *opt_evdev;
+static int opt_fdnum = -1;
+static char *opt_socket_path;
+static gboolean opt_nograb;
+static gboolean opt_print_caps;
+
+static GOptionEntry entries[] = {
+    { "print-capabilities", 'c', 0, G_OPTION_ARG_NONE, &opt_print_caps,
+      "Print capabilities", NULL },
+    { "no-grab", 'n', 0, G_OPTION_ARG_NONE, &opt_nograb,
+      "Don't grab device", NULL },
+    { "fd", 'f', 0, G_OPTION_ARG_INT, &opt_fdnum,
+      "Use inherited fd socket", "FDNUM" },
+    { "socket-path", 's', 0, G_OPTION_ARG_FILENAME, &opt_socket_path,
+      "Use UNIX socket path", "PATH" },
+    { "evdev-path", 'p', 0, G_OPTION_ARG_FILENAME, &opt_evdev,
+      "evdev input device path", "PATH" },
+    { NULL, }
+};
+
+int
+main(int argc, char *argv[])
+{
+    GMainLoop *loop = NULL;
+    VuInput vi = { 0, };
+    int rc, ver, fd;
+    virtio_input_config id;
+    struct input_id ids;
+    GError *error = NULL;
+    GOptionContext *context;
+
+    context = g_option_context_new(NULL);
+    g_option_context_add_main_entries(context, entries, NULL);
+    if (!g_option_context_parse(context, &argc, &argv, &error)) {
+        g_printerr("Option parsing failed: %s\n", error->message);
+        exit(EXIT_FAILURE);
+    }
+    if (opt_print_caps) {
+        g_print("{\n");
+        g_print("  \"type\": \"input\",\n");
+        g_print("  \"features\": [\n");
+        g_print("    \"evdev-path\",\n");
+        g_print("    \"no-grab\"\n");
+        g_print("  ]\n");
+        g_print("}\n");
+        exit(EXIT_SUCCESS);
+    }
+    if (!opt_evdev) {
+        g_printerr("Please specify an evdev path\n");
+        exit(EXIT_FAILURE);
+    }
+    if ((!!opt_socket_path + (opt_fdnum != -1)) != 1) {
+        g_printerr("Please specify either --fd or --socket-path\n");
+        exit(EXIT_FAILURE);
+    }
+
+    vi.evdevfd = open(opt_evdev, O_RDWR);
+    if (vi.evdevfd < 0) {
+        g_printerr("Failed to open evdev: %s\n", g_strerror(errno));
+        exit(EXIT_FAILURE);
+    }
+
+    rc = ioctl(vi.evdevfd, EVIOCGVERSION, &ver);
+    if (rc < 0) {
+        g_printerr("%s: is not an evdev device\n", argv[1]);
+        exit(EXIT_FAILURE);
+    }
+
+    if (!opt_nograb) {
+        rc = ioctl(vi.evdevfd, EVIOCGRAB, 1);
+        if (rc < 0) {
+            g_printerr("Failed to grab device\n");
+            exit(EXIT_FAILURE);
+        }
+    }
+
+    vi.config = g_array_new(false, false, sizeof(virtio_input_config));
+    memset(&id, 0, sizeof(id));
+    ioctl(vi.evdevfd, EVIOCGNAME(sizeof(id.u.string) - 1), id.u.string);
+    id.select = VIRTIO_INPUT_CFG_ID_NAME;
+    id.size = strlen(id.u.string);
+    g_array_append_val(vi.config, id);
+
+    if (ioctl(vi.evdevfd, EVIOCGID, &ids) == 0) {
+        memset(&id, 0, sizeof(id));
+        id.select = VIRTIO_INPUT_CFG_ID_DEVIDS;
+        id.size = sizeof(struct virtio_input_devids);
+        id.u.ids.bustype = cpu_to_le16(ids.bustype);
+        id.u.ids.vendor  = cpu_to_le16(ids.vendor);
+        id.u.ids.product = cpu_to_le16(ids.product);
+        id.u.ids.version = cpu_to_le16(ids.version);
+        g_array_append_val(vi.config, id);
+    }
+
+    vi_bits_config(&vi, EV_KEY, KEY_CNT);
+    vi_bits_config(&vi, EV_REL, REL_CNT);
+    vi_bits_config(&vi, EV_ABS, ABS_CNT);
+    vi_bits_config(&vi, EV_MSC, MSC_CNT);
+    vi_bits_config(&vi, EV_SW,  SW_CNT);
+    g_debug("config length: %u", vi.config->len);
+
+    if (opt_socket_path) {
+        int lsock = unix_sock_new(opt_socket_path);
+        fd = accept(lsock, NULL, NULL);
+        close(lsock);
+    } else {
+        fd = opt_fdnum;
+    }
+    if (fd == -1) {
+        g_printerr("Invalid socket");
+        exit(EXIT_FAILURE);
+    }
+    vug_init(&vi.dev, fd, vi_panic, &vuiface);
+
+    loop = g_main_loop_new(NULL, FALSE);
+    g_main_loop_run(loop);
+    g_main_loop_unref(loop);
+
+    vug_deinit(&vi.dev);
+
+    if (vi.evsrc) {
+        g_source_unref(vi.evsrc);
+    }
+    g_array_free(vi.config, TRUE);
+    g_free(vi.queue);
+    return 0;
+}
diff --git a/MAINTAINERS b/MAINTAINERS
index a601b97adb..d4eb155b2a 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1500,6 +1500,7 @@ S: Maintained
 F: hw/input/vhost-user-input.c
 F: hw/input/virtio-input*.c
 F: include/hw/virtio/virtio-input.h
+F: contrib/vhost-user-input/*
 
 virtio-serial
 M: Amit Shah <amit@kernel.org>
diff --git a/Makefile b/Makefile
index ba32d810ea..c7abeb0123 100644
--- a/Makefile
+++ b/Makefile
@@ -401,6 +401,7 @@ dummy := $(call unnest-vars,, \
                 libvhost-user-obj-y \
                 vhost-user-scsi-obj-y \
                 vhost-user-blk-obj-y \
+                vhost-user-input-obj-y \
                 qga-vss-dll-obj-y \
                 block-obj-y \
                 block-obj-m \
@@ -606,6 +607,8 @@ vhost-user-blk$(EXESUF): $(vhost-user-blk-obj-y) libvhost-user.a
 rdmacm-mux$(EXESUF): LIBS += "-libumad"
 rdmacm-mux$(EXESUF): $(rdmacm-mux-obj-y) $(COMMON_LDADDS)
 	$(call LINK, $^)
+vhost-user-input$(EXESUF): $(vhost-user-input-obj-y) libvhost-user.a libqemuutil.a
+	$(call LINK, $^)
 
 module_block.h: $(SRC_PATH)/scripts/modules/module_block.py config-host.mak
 	$(call quiet-command,$(PYTHON) $< $@ \
diff --git a/Makefile.objs b/Makefile.objs
index 6e91ee5674..8084d9270c 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -124,6 +124,7 @@ vhost-user-scsi.o-libs := $(LIBISCSI_LIBS)
 vhost-user-scsi-obj-y = contrib/vhost-user-scsi/
 vhost-user-blk-obj-y = contrib/vhost-user-blk/
 rdmacm-mux-obj-y = contrib/rdmacm-mux/
+vhost-user-input-obj-y = contrib/vhost-user-input/
 
 ######################################################################
 trace-events-subdirs =
diff --git a/configure b/configure
index f9177dc479..eb4e52f4fd 100755
--- a/configure
+++ b/configure
@@ -5874,6 +5874,9 @@ if test "$want_tools" = "yes" ; then
   if [ "$curl" = "yes" ]; then
       tools="elf2dmp\$(EXESUF) $tools"
   fi
+  if [ "$vhost_user" = "yes" ] && [ "$linux" = "yes" ] ; then
+    tools="vhost-user-input\$(EXESUF) $tools"
+  fi
 fi
 if test "$softmmu" = yes ; then
   if test "$linux" = yes; then
diff --git a/contrib/vhost-user-input/Makefile.objs b/contrib/vhost-user-input/Makefile.objs
new file mode 100644
index 0000000000..b1fad90d51
--- /dev/null
+++ b/contrib/vhost-user-input/Makefile.objs
@@ -0,0 +1 @@
+vhost-user-input-obj-y = main.o
-- 
2.21.0.4.g36eb1cb9cf