* [PATCH V3 0/4] Change vring space from nomal memory to dma coherent memory
@ 2020-10-22 5:06 Sherry Sun
2020-10-22 5:06 ` [PATCH V3 1/4] misc: vop: change the way of allocating vring and device page Sherry Sun
` (3 more replies)
0 siblings, 4 replies; 13+ messages in thread
From: Sherry Sun @ 2020-10-22 5:06 UTC (permalink / raw)
To: hch, sudeep.dutt, ashutosh.dixit, arnd, gregkh, kishon,
lorenzo.pieralisi
Cc: linux-kernel, linux-pci, linux-imx
Changes in V3:
1. Change the device page allocation method of the Intel mic layer in Patch 1 to
align with the vring allocation.
2. Move the vring physical address changes in mmap callback from Prach 3 to 1.
3. Use must_be_zero instead of directly deleting used_address_updated in
Patch 2 to avoid the influence of ABI change.
(I tried to use dma_mmap_coherent api in Patch 4 as Christoph suggested, but
met some issues explained here https://lore.kernel.org/patchwork/patch/1313327/,
so there is no change to Patch 4, and still can't find a better way than
patch 3)
The original vop driver only supports dma coherent device, as it allocates and
maps vring by _get_free_pages and dma_map_single, but not use
dma_sync_single_for_cpu/device to sync the updates of device_page/vring between
EP and RC, which will cause memory synchronization problem for device don't
support hardware dma coherent.
And allocate vrings use dma_alloc_coherent is a common way in kernel, as the
memory interacted between two systems should use consistent memory to avoid
caching effects. So here add noncoherent platform support for vop driver.
Also add some related dma changes to make sure noncoherent platform works
well.
Sherry Sun (4):
misc: vop: change the way of allocating vring and device page
misc: vop: do not allocate and reassign the used ring
misc: vop: simply return the saved dma address instead of virt_to_phys
misc: vop: mapping kernel memory to user space as noncached
drivers/misc/mic/bus/vop_bus.h | 2 +
drivers/misc/mic/host/mic_boot.c | 8 +++
drivers/misc/mic/host/mic_main.c | 15 ++----
drivers/misc/mic/vop/vop_debugfs.c | 2 -
drivers/misc/mic/vop/vop_main.c | 48 +++--------------
drivers/misc/mic/vop/vop_vringh.c | 84 +++++++-----------------------
include/uapi/linux/mic_common.h | 5 +-
7 files changed, 42 insertions(+), 122 deletions(-)
--
2.17.1
^ permalink raw reply [flat|nested] 13+ messages in thread
* [PATCH V3 1/4] misc: vop: change the way of allocating vring and device page
2020-10-22 5:06 [PATCH V3 0/4] Change vring space from nomal memory to dma coherent memory Sherry Sun
@ 2020-10-22 5:06 ` Sherry Sun
2020-10-22 7:58 ` kernel test robot
2020-10-23 9:25 ` Christoph Hellwig
2020-10-22 5:06 ` [PATCH V3 2/4] misc: vop: do not allocate and reassign the used ring Sherry Sun
` (2 subsequent siblings)
3 siblings, 2 replies; 13+ messages in thread
From: Sherry Sun @ 2020-10-22 5:06 UTC (permalink / raw)
To: hch, sudeep.dutt, ashutosh.dixit, arnd, gregkh, kishon,
lorenzo.pieralisi
Cc: linux-kernel, linux-pci, linux-imx
Allocate vrings use dma_alloc_coherent is a common way in kernel. As the
memory interacted between two systems should use consistent memory to
avoid caching effects, same as device page memory.
The orginal way use __get_free_pages and dma_map_single to allocate and
map vring, but not use dma_sync_single_for_cpu/device api to sync the
changes of vring between EP and RC, which will cause memory
synchronization problem for those devices which don't support hardware
dma coherent.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
---
drivers/misc/mic/host/mic_main.c | 15 +++--------
drivers/misc/mic/vop/vop_vringh.c | 43 +++++++++----------------------
2 files changed, 16 insertions(+), 42 deletions(-)
diff --git a/drivers/misc/mic/host/mic_main.c b/drivers/misc/mic/host/mic_main.c
index ea4608527ea0..ebacaa35cb47 100644
--- a/drivers/misc/mic/host/mic_main.c
+++ b/drivers/misc/mic/host/mic_main.c
@@ -10,6 +10,7 @@
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/poll.h>
+#include <linux/dma-mapping.h>
#include <linux/mic_common.h>
#include "../common/mic_dev.h"
@@ -48,18 +49,11 @@ static struct ida g_mic_ida;
/* Initialize the device page */
static int mic_dp_init(struct mic_device *mdev)
{
- mdev->dp = kzalloc(MIC_DP_SIZE, GFP_KERNEL);
+ mdev->dp = dma_alloc_coherent(&mdev->pdev->dev, MIC_DP_SIZE,
+ &mdev->dp_dma_addr, GFP_KERNEL);
if (!mdev->dp)
return -ENOMEM;
- mdev->dp_dma_addr = mic_map_single(mdev,
- mdev->dp, MIC_DP_SIZE);
- if (mic_map_error(mdev->dp_dma_addr)) {
- kfree(mdev->dp);
- dev_err(&mdev->pdev->dev, "%s %d err %d\n",
- __func__, __LINE__, -ENOMEM);
- return -ENOMEM;
- }
mdev->ops->write_spad(mdev, MIC_DPLO_SPAD, mdev->dp_dma_addr);
mdev->ops->write_spad(mdev, MIC_DPHI_SPAD, mdev->dp_dma_addr >> 32);
return 0;
@@ -68,8 +62,7 @@ static int mic_dp_init(struct mic_device *mdev)
/* Uninitialize the device page */
static void mic_dp_uninit(struct mic_device *mdev)
{
- mic_unmap_single(mdev, mdev->dp_dma_addr, MIC_DP_SIZE);
- kfree(mdev->dp);
+ dma_free_coherent(&mdev->pdev->dev, MIC_DP_SIZE, mdev->dp, mdev->dp_dma_addr);
}
/**
diff --git a/drivers/misc/mic/vop/vop_vringh.c b/drivers/misc/mic/vop/vop_vringh.c
index 7014ffe88632..2cc3c22482b5 100644
--- a/drivers/misc/mic/vop/vop_vringh.c
+++ b/drivers/misc/mic/vop/vop_vringh.c
@@ -298,9 +298,8 @@ static int vop_virtio_add_device(struct vop_vdev *vdev,
mutex_init(&vvr->vr_mutex);
vr_size = PAGE_ALIGN(round_up(vring_size(num, MIC_VIRTIO_RING_ALIGN), 4) +
sizeof(struct _mic_vring_info));
- vr->va = (void *)
- __get_free_pages(GFP_KERNEL | __GFP_ZERO,
- get_order(vr_size));
+ vr->va = dma_alloc_coherent(vop_dev(vdev), vr_size, &vr_addr,
+ GFP_KERNEL);
if (!vr->va) {
ret = -ENOMEM;
dev_err(vop_dev(vdev), "%s %d err %d\n",
@@ -310,15 +309,6 @@ static int vop_virtio_add_device(struct vop_vdev *vdev,
vr->len = vr_size;
vr->info = vr->va + round_up(vring_size(num, MIC_VIRTIO_RING_ALIGN), 4);
vr->info->magic = cpu_to_le32(MIC_MAGIC + vdev->virtio_id + i);
- vr_addr = dma_map_single(&vpdev->dev, vr->va, vr_size,
- DMA_BIDIRECTIONAL);
- if (dma_mapping_error(&vpdev->dev, vr_addr)) {
- free_pages((unsigned long)vr->va, get_order(vr_size));
- ret = -ENOMEM;
- dev_err(vop_dev(vdev), "%s %d err %d\n",
- __func__, __LINE__, ret);
- goto err;
- }
vqconfig[i].address = cpu_to_le64(vr_addr);
vring_init(&vr->vr, num, vr->va, MIC_VIRTIO_RING_ALIGN);
@@ -339,11 +329,8 @@ static int vop_virtio_add_device(struct vop_vdev *vdev,
dev_dbg(&vpdev->dev,
"%s %d index %d va %p info %p vr_size 0x%x\n",
__func__, __LINE__, i, vr->va, vr->info, vr_size);
- vvr->buf = (void *)__get_free_pages(GFP_KERNEL,
- get_order(VOP_INT_DMA_BUF_SIZE));
- vvr->buf_da = dma_map_single(&vpdev->dev,
- vvr->buf, VOP_INT_DMA_BUF_SIZE,
- DMA_BIDIRECTIONAL);
+ vvr->buf = dma_alloc_coherent(vop_dev(vdev), VOP_INT_DMA_BUF_SIZE,
+ &vvr->buf_da, GFP_KERNEL);
}
snprintf(irqname, sizeof(irqname), "vop%dvirtio%d", vpdev->index,
@@ -382,10 +369,8 @@ static int vop_virtio_add_device(struct vop_vdev *vdev,
for (j = 0; j < i; j++) {
struct vop_vringh *vvr = &vdev->vvr[j];
- dma_unmap_single(&vpdev->dev, le64_to_cpu(vqconfig[j].address),
- vvr->vring.len, DMA_BIDIRECTIONAL);
- free_pages((unsigned long)vvr->vring.va,
- get_order(vvr->vring.len));
+ dma_free_coherent(vop_dev(vdev), vvr->vring.len, vvr->vring.va,
+ le64_to_cpu(vqconfig[j].address));
}
return ret;
}
@@ -433,17 +418,12 @@ static void vop_virtio_del_device(struct vop_vdev *vdev)
for (i = 0; i < vdev->dd->num_vq; i++) {
struct vop_vringh *vvr = &vdev->vvr[i];
- dma_unmap_single(&vpdev->dev,
- vvr->buf_da, VOP_INT_DMA_BUF_SIZE,
- DMA_BIDIRECTIONAL);
- free_pages((unsigned long)vvr->buf,
- get_order(VOP_INT_DMA_BUF_SIZE));
+ dma_free_coherent(vop_dev(vdev), VOP_INT_DMA_BUF_SIZE,
+ vvr->buf, vvr->buf_da);
vringh_kiov_cleanup(&vvr->riov);
vringh_kiov_cleanup(&vvr->wiov);
- dma_unmap_single(&vpdev->dev, le64_to_cpu(vqconfig[i].address),
- vvr->vring.len, DMA_BIDIRECTIONAL);
- free_pages((unsigned long)vvr->vring.va,
- get_order(vvr->vring.len));
+ dma_free_coherent(vop_dev(vdev), vvr->vring.len, vvr->vring.va,
+ le64_to_cpu(vqconfig[i].address));
}
/*
* Order the type update with previous stores. This write barrier
@@ -1047,6 +1027,7 @@ vop_query_offset(struct vop_vdev *vdev, unsigned long offset,
unsigned long *size, unsigned long *pa)
{
struct vop_device *vpdev = vdev->vpdev;
+ struct mic_vqconfig *vqconfig = mic_vq_config(vdev->dd);
unsigned long start = MIC_DP_SIZE;
int i;
@@ -1068,7 +1049,7 @@ vop_query_offset(struct vop_vdev *vdev, unsigned long offset,
struct vop_vringh *vvr = &vdev->vvr[i];
if (offset == start) {
- *pa = virt_to_phys(vvr->vring.va);
+ *pa = vqconfig[i].address;
*size = vvr->vring.len;
return 0;
}
--
2.17.1
^ permalink raw reply related [flat|nested] 13+ messages in thread
* [PATCH V3 2/4] misc: vop: do not allocate and reassign the used ring
2020-10-22 5:06 [PATCH V3 0/4] Change vring space from nomal memory to dma coherent memory Sherry Sun
2020-10-22 5:06 ` [PATCH V3 1/4] misc: vop: change the way of allocating vring and device page Sherry Sun
@ 2020-10-22 5:06 ` Sherry Sun
2020-10-22 8:53 ` kernel test robot
2020-10-23 9:26 ` Christoph Hellwig
2020-10-22 5:06 ` [PATCH V3 3/4] misc: vop: simply return the saved dma address instead of virt_to_phys Sherry Sun
2020-10-22 5:06 ` [PATCH V3 4/4] misc: vop: mapping kernel memory to user space as noncached Sherry Sun
3 siblings, 2 replies; 13+ messages in thread
From: Sherry Sun @ 2020-10-22 5:06 UTC (permalink / raw)
To: hch, sudeep.dutt, ashutosh.dixit, arnd, gregkh, kishon,
lorenzo.pieralisi
Cc: linux-kernel, linux-pci, linux-imx
We don't need to allocate and reassign the used ring here and remove the
used_address_updated flag.Since RC has allocated the entire vring,
including the used ring. Simply add the corresponding offset can get the
used ring address.
If following the orginal way to reassign the used ring, will encounter a
problem. When host finished with descriptor, it will update the used
ring with putused_kern api, if reassign used ring at EP side, used
ring will be io device memory for RC, use memcpy in putused_kern will
cause kernel panic.
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
---
drivers/misc/mic/vop/vop_debugfs.c | 2 --
drivers/misc/mic/vop/vop_main.c | 48 ++++--------------------------
drivers/misc/mic/vop/vop_vringh.c | 31 -------------------
include/uapi/linux/mic_common.h | 5 ++--
4 files changed, 8 insertions(+), 78 deletions(-)
diff --git a/drivers/misc/mic/vop/vop_debugfs.c b/drivers/misc/mic/vop/vop_debugfs.c
index 9d4f175f4dd1..05eca4a98585 100644
--- a/drivers/misc/mic/vop/vop_debugfs.c
+++ b/drivers/misc/mic/vop/vop_debugfs.c
@@ -79,8 +79,6 @@ static int vop_dp_show(struct seq_file *s, void *pos)
seq_printf(s, "Vdev reset %d\n", dc->vdev_reset);
seq_printf(s, "Guest Ack %d ", dc->guest_ack);
seq_printf(s, "Host ack %d\n", dc->host_ack);
- seq_printf(s, "Used address updated %d ",
- dc->used_address_updated);
seq_printf(s, "Vdev 0x%llx\n", dc->vdev);
seq_printf(s, "c2h doorbell %d ", dc->c2h_vdev_db);
seq_printf(s, "h2c doorbell %d\n", dc->h2c_vdev_db);
diff --git a/drivers/misc/mic/vop/vop_main.c b/drivers/misc/mic/vop/vop_main.c
index 714b94f42d38..1ccc94dfd6ac 100644
--- a/drivers/misc/mic/vop/vop_main.c
+++ b/drivers/misc/mic/vop/vop_main.c
@@ -250,10 +250,6 @@ static void vop_del_vq(struct virtqueue *vq, int n)
struct _vop_vdev *vdev = to_vopvdev(vq->vdev);
struct vop_device *vpdev = vdev->vpdev;
- dma_unmap_single(&vpdev->dev, vdev->used[n],
- vdev->used_size[n], DMA_BIDIRECTIONAL);
- free_pages((unsigned long)vdev->used_virt[n],
- get_order(vdev->used_size[n]));
vring_del_virtqueue(vq);
vpdev->hw_ops->unmap(vpdev, vdev->vr[n]);
vdev->vr[n] = NULL;
@@ -340,8 +336,8 @@ static struct virtqueue *vop_find_vq(struct virtio_device *dev,
vdev->used_size[index] = PAGE_ALIGN(sizeof(__u16) * 3 +
sizeof(struct vring_used_elem) *
le16_to_cpu(config.num));
- used = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
- get_order(vdev->used_size[index]));
+ used = va + PAGE_ALIGN(sizeof(struct vring_desc) * le16_to_cpu(config.num) +
+ sizeof(__u16) * (3 + le16_to_cpu(config.num)));
vdev->used_virt[index] = used;
if (!used) {
err = -ENOMEM;
@@ -355,27 +351,15 @@ static struct virtqueue *vop_find_vq(struct virtio_device *dev,
name, used);
if (!vq) {
err = -ENOMEM;
- goto free_used;
+ goto unmap;
}
- vdev->used[index] = dma_map_single(&vpdev->dev, used,
- vdev->used_size[index],
- DMA_BIDIRECTIONAL);
- if (dma_mapping_error(&vpdev->dev, vdev->used[index])) {
- err = -ENOMEM;
- dev_err(_vop_dev(vdev), "%s %d err %d\n",
- __func__, __LINE__, err);
- goto del_vq;
- }
+ vdev->used[index] = config.address + PAGE_ALIGN(sizeof(struct vring_desc) * le16_to_cpu(config.num) +
+ sizeof(__u16) * (3 + le16_to_cpu(config.num)));
writeq(vdev->used[index], &vqconfig->used_address);
vq->priv = vdev;
return vq;
-del_vq:
- vring_del_virtqueue(vq);
-free_used:
- free_pages((unsigned long)used,
- get_order(vdev->used_size[index]));
unmap:
vpdev->hw_ops->unmap(vpdev, vdev->vr[index]);
return ERR_PTR(err);
@@ -388,9 +372,7 @@ static int vop_find_vqs(struct virtio_device *dev, unsigned nvqs,
struct irq_affinity *desc)
{
struct _vop_vdev *vdev = to_vopvdev(dev);
- struct vop_device *vpdev = vdev->vpdev;
- struct mic_device_ctrl __iomem *dc = vdev->dc;
- int i, err, retry, queue_idx = 0;
+ int i, err, queue_idx = 0;
/* We must have this many virtqueues. */
if (nvqs > ioread8(&vdev->desc->num_vq))
@@ -412,24 +394,6 @@ static int vop_find_vqs(struct virtio_device *dev, unsigned nvqs,
}
}
- iowrite8(1, &dc->used_address_updated);
- /*
- * Send an interrupt to the host to inform it that used
- * rings have been re-assigned.
- */
- vpdev->hw_ops->send_intr(vpdev, vdev->c2h_vdev_db);
- for (retry = 100; --retry;) {
- if (!ioread8(&dc->used_address_updated))
- break;
- msleep(100);
- }
-
- dev_dbg(_vop_dev(vdev), "%s: retry: %d\n", __func__, retry);
- if (!retry) {
- err = -ENODEV;
- goto error;
- }
-
return 0;
error:
vop_del_vqs(dev);
diff --git a/drivers/misc/mic/vop/vop_vringh.c b/drivers/misc/mic/vop/vop_vringh.c
index 2cc3c22482b5..cc928d45af5a 100644
--- a/drivers/misc/mic/vop/vop_vringh.c
+++ b/drivers/misc/mic/vop/vop_vringh.c
@@ -53,33 +53,6 @@ static void _vop_notify(struct vringh *vrh)
vpdev->hw_ops->send_intr(vpdev, db);
}
-static void vop_virtio_init_post(struct vop_vdev *vdev)
-{
- struct mic_vqconfig *vqconfig = mic_vq_config(vdev->dd);
- struct vop_device *vpdev = vdev->vpdev;
- int i, used_size;
-
- for (i = 0; i < vdev->dd->num_vq; i++) {
- used_size = PAGE_ALIGN(sizeof(u16) * 3 +
- sizeof(struct vring_used_elem) *
- le16_to_cpu(vqconfig->num));
- if (!le64_to_cpu(vqconfig[i].used_address)) {
- dev_warn(vop_dev(vdev), "used_address zero??\n");
- continue;
- }
- vdev->vvr[i].vrh.vring.used =
- (void __force *)vpdev->hw_ops->remap(
- vpdev,
- le64_to_cpu(vqconfig[i].used_address),
- used_size);
- }
-
- vdev->dc->used_address_updated = 0;
-
- dev_info(vop_dev(vdev), "%s: device type %d LINKUP\n",
- __func__, vdev->virtio_id);
-}
-
static inline void vop_virtio_device_reset(struct vop_vdev *vdev)
{
int i;
@@ -130,9 +103,6 @@ static void vop_bh_handler(struct work_struct *work)
struct vop_vdev *vdev = container_of(work, struct vop_vdev,
virtio_bh_work);
- if (vdev->dc->used_address_updated)
- vop_virtio_init_post(vdev);
-
if (vdev->dc->vdev_reset)
vop_virtio_device_reset(vdev);
@@ -250,7 +220,6 @@ static void vop_init_device_ctrl(struct vop_vdev *vdev,
dc->guest_ack = 0;
dc->vdev_reset = 0;
dc->host_ack = 0;
- dc->used_address_updated = 0;
dc->c2h_vdev_db = -1;
dc->h2c_vdev_db = -1;
vdev->dc = dc;
diff --git a/include/uapi/linux/mic_common.h b/include/uapi/linux/mic_common.h
index 504e523f702c..fe660d486b20 100644
--- a/include/uapi/linux/mic_common.h
+++ b/include/uapi/linux/mic_common.h
@@ -56,8 +56,7 @@ struct mic_device_desc {
* @vdev_reset: Set to 1 by guest to indicate virtio device has been reset.
* @guest_ack: Set to 1 by guest to ack a command.
* @host_ack: Set to 1 by host to ack a command.
- * @used_address_updated: Set to 1 by guest when the used address should be
- * updated.
+ * @must_be_zero: Reserved because this bit is no longer needed.
* @c2h_vdev_db: The doorbell number to be used by guest. Set by host.
* @h2c_vdev_db: The doorbell number to be used by host. Set by guest.
*/
@@ -67,7 +66,7 @@ struct mic_device_ctrl {
__u8 vdev_reset;
__u8 guest_ack;
__u8 host_ack;
- __u8 used_address_updated;
+ __u8 must_be_zero;
__s8 c2h_vdev_db;
__s8 h2c_vdev_db;
} __attribute__ ((aligned(8)));
--
2.17.1
^ permalink raw reply related [flat|nested] 13+ messages in thread
* [PATCH V3 3/4] misc: vop: simply return the saved dma address instead of virt_to_phys
2020-10-22 5:06 [PATCH V3 0/4] Change vring space from nomal memory to dma coherent memory Sherry Sun
2020-10-22 5:06 ` [PATCH V3 1/4] misc: vop: change the way of allocating vring and device page Sherry Sun
2020-10-22 5:06 ` [PATCH V3 2/4] misc: vop: do not allocate and reassign the used ring Sherry Sun
@ 2020-10-22 5:06 ` Sherry Sun
2020-10-22 5:06 ` [PATCH V3 4/4] misc: vop: mapping kernel memory to user space as noncached Sherry Sun
3 siblings, 0 replies; 13+ messages in thread
From: Sherry Sun @ 2020-10-22 5:06 UTC (permalink / raw)
To: hch, sudeep.dutt, ashutosh.dixit, arnd, gregkh, kishon,
lorenzo.pieralisi
Cc: linux-kernel, linux-pci, linux-imx
The device page and vring should use consistent memory which are
allocated by dma_alloc_coherent api, when user space wants to get its
physical address, virt_to_phys cannot be used, should simply return the
saved device page dma address by get_dp_dma callback and the vring dma
address saved in mic_vqconfig.
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
---
drivers/misc/mic/bus/vop_bus.h | 2 ++
drivers/misc/mic/host/mic_boot.c | 8 ++++++++
drivers/misc/mic/vop/vop_vringh.c | 8 +++++++-
3 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/drivers/misc/mic/bus/vop_bus.h b/drivers/misc/mic/bus/vop_bus.h
index 4fa02808c1e2..d891eacae358 100644
--- a/drivers/misc/mic/bus/vop_bus.h
+++ b/drivers/misc/mic/bus/vop_bus.h
@@ -75,6 +75,7 @@ struct vop_driver {
* node to add/remove/configure virtio devices.
* @get_dp: Get access to the virtio device page used by the self
* node to add/remove/configure virtio devices.
+ * @get_dp_dma: Get dma address of the virtio device page.
* @send_intr: Send an interrupt to the peer node on a specified doorbell.
* @remap: Map a buffer with the specified DMA address and length.
* @unmap: Unmap a buffer previously mapped.
@@ -92,6 +93,7 @@ struct vop_hw_ops {
void (*ack_interrupt)(struct vop_device *vpdev, int num);
void __iomem * (*get_remote_dp)(struct vop_device *vpdev);
void * (*get_dp)(struct vop_device *vpdev);
+ dma_addr_t (*get_dp_dma)(struct vop_device *vpdev);
void (*send_intr)(struct vop_device *vpdev, int db);
void __iomem * (*remap)(struct vop_device *vpdev,
dma_addr_t pa, size_t len);
diff --git a/drivers/misc/mic/host/mic_boot.c b/drivers/misc/mic/host/mic_boot.c
index 8cb85b8b3e19..9591bf609f57 100644
--- a/drivers/misc/mic/host/mic_boot.c
+++ b/drivers/misc/mic/host/mic_boot.c
@@ -89,6 +89,13 @@ static void *__mic_get_dp(struct vop_device *vpdev)
return mdev->dp;
}
+static dma_addr_t __mic_get_dp_dma(struct vop_device *vpdev)
+{
+ struct mic_device *mdev = vpdev_to_mdev(&vpdev->dev);
+
+ return mdev->dp_dma_addr;
+}
+
static void __iomem *__mic_get_remote_dp(struct vop_device *vpdev)
{
return NULL;
@@ -120,6 +127,7 @@ static struct vop_hw_ops vop_hw_ops = {
.ack_interrupt = __mic_ack_interrupt,
.next_db = __mic_next_db,
.get_dp = __mic_get_dp,
+ .get_dp_dma = __mic_get_dp_dma,
.get_remote_dp = __mic_get_remote_dp,
.send_intr = __mic_send_intr,
.remap = __mic_ioremap,
diff --git a/drivers/misc/mic/vop/vop_vringh.c b/drivers/misc/mic/vop/vop_vringh.c
index cc928d45af5a..b5612183dcb8 100644
--- a/drivers/misc/mic/vop/vop_vringh.c
+++ b/drivers/misc/mic/vop/vop_vringh.c
@@ -1009,7 +1009,13 @@ vop_query_offset(struct vop_vdev *vdev, unsigned long offset,
* ....
*/
if (!offset) {
- *pa = virt_to_phys(vpdev->hw_ops->get_dp(vpdev));
+ if (vpdev->hw_ops->get_dp_dma)
+ *pa = vpdev->hw_ops->get_dp_dma(vpdev);
+ else {
+ dev_err(vop_dev(vdev), "can't get device page physical address\n");
+ return -EINVAL;
+ }
+
*size = MIC_DP_SIZE;
return 0;
}
--
2.17.1
^ permalink raw reply related [flat|nested] 13+ messages in thread
* [PATCH V3 4/4] misc: vop: mapping kernel memory to user space as noncached
2020-10-22 5:06 [PATCH V3 0/4] Change vring space from nomal memory to dma coherent memory Sherry Sun
` (2 preceding siblings ...)
2020-10-22 5:06 ` [PATCH V3 3/4] misc: vop: simply return the saved dma address instead of virt_to_phys Sherry Sun
@ 2020-10-22 5:06 ` Sherry Sun
2020-10-23 9:28 ` Christoph Hellwig
3 siblings, 1 reply; 13+ messages in thread
From: Sherry Sun @ 2020-10-22 5:06 UTC (permalink / raw)
To: hch, sudeep.dutt, ashutosh.dixit, arnd, gregkh, kishon,
lorenzo.pieralisi
Cc: linux-kernel, linux-pci, linux-imx
Mapping kernel space memory to user space as noncached, since user space
need check the updates of avail_idx and device page flags timely.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
---
drivers/misc/mic/vop/vop_vringh.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/misc/mic/vop/vop_vringh.c b/drivers/misc/mic/vop/vop_vringh.c
index b5612183dcb8..b75c2b713a3b 100644
--- a/drivers/misc/mic/vop/vop_vringh.c
+++ b/drivers/misc/mic/vop/vop_vringh.c
@@ -1058,7 +1058,7 @@ static int vop_mmap(struct file *f, struct vm_area_struct *vma)
}
err = remap_pfn_range(vma, vma->vm_start + offset,
pa >> PAGE_SHIFT, size,
- vma->vm_page_prot);
+ pgprot_noncached(vma->vm_page_prot));
if (err)
goto ret;
size_rem -= size;
--
2.17.1
^ permalink raw reply related [flat|nested] 13+ messages in thread
* Re: [PATCH V3 1/4] misc: vop: change the way of allocating vring and device page
2020-10-22 5:06 ` [PATCH V3 1/4] misc: vop: change the way of allocating vring and device page Sherry Sun
@ 2020-10-22 7:58 ` kernel test robot
2020-10-23 9:25 ` Christoph Hellwig
1 sibling, 0 replies; 13+ messages in thread
From: kernel test robot @ 2020-10-22 7:58 UTC (permalink / raw)
To: Sherry Sun, hch, sudeep.dutt, ashutosh.dixit, arnd, gregkh,
kishon, lorenzo.pieralisi
Cc: kbuild-all, linux-kernel, linux-pci, linux-imx
[-- Attachment #1: Type: text/plain, Size: 3037 bytes --]
Hi Sherry,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on char-misc/char-misc-testing]
[also build test WARNING on soc/for-next linus/master v5.9 next-20201022]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Sherry-Sun/Change-vring-space-from-nomal-memory-to-dma-coherent-memory/20201022-131008
base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git f3277cbfba763cd2826396521b9296de67cf1bbc
config: i386-randconfig-s002-20201022 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0
reproduce:
# apt-get install sparse
# sparse version: v0.6.3-dirty
# https://github.com/0day-ci/linux/commit/6851e84ec2f16ab12b04b2a5bf61b05465d450e6
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Sherry-Sun/Change-vring-space-from-nomal-memory-to-dma-coherent-memory/20201022-131008
git checkout 6851e84ec2f16ab12b04b2a5bf61b05465d450e6
# save the attached .config to linux build tree
make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=i386
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
"sparse warnings: (new ones prefixed by >>)"
>> drivers/misc/mic/vop/vop_vringh.c:1052:29: sparse: sparse: incorrect type in assignment (different base types) @@ expected unsigned long @@ got restricted __le64 [usertype] address @@
>> drivers/misc/mic/vop/vop_vringh.c:1052:29: sparse: expected unsigned long
>> drivers/misc/mic/vop/vop_vringh.c:1052:29: sparse: got restricted __le64 [usertype] address
vim +1052 drivers/misc/mic/vop/vop_vringh.c
1024
1025 static inline int
1026 vop_query_offset(struct vop_vdev *vdev, unsigned long offset,
1027 unsigned long *size, unsigned long *pa)
1028 {
1029 struct vop_device *vpdev = vdev->vpdev;
1030 struct mic_vqconfig *vqconfig = mic_vq_config(vdev->dd);
1031 unsigned long start = MIC_DP_SIZE;
1032 int i;
1033
1034 /*
1035 * MMAP interface is as follows:
1036 * offset region
1037 * 0x0 virtio device_page
1038 * 0x1000 first vring
1039 * 0x1000 + size of 1st vring second vring
1040 * ....
1041 */
1042 if (!offset) {
1043 *pa = virt_to_phys(vpdev->hw_ops->get_dp(vpdev));
1044 *size = MIC_DP_SIZE;
1045 return 0;
1046 }
1047
1048 for (i = 0; i < vdev->dd->num_vq; i++) {
1049 struct vop_vringh *vvr = &vdev->vvr[i];
1050
1051 if (offset == start) {
> 1052 *pa = vqconfig[i].address;
1053 *size = vvr->vring.len;
1054 return 0;
1055 }
1056 start += vvr->vring.len;
1057 }
1058 return -1;
1059 }
1060
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 36245 bytes --]
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH V3 2/4] misc: vop: do not allocate and reassign the used ring
2020-10-22 5:06 ` [PATCH V3 2/4] misc: vop: do not allocate and reassign the used ring Sherry Sun
@ 2020-10-22 8:53 ` kernel test robot
2020-10-23 9:26 ` Christoph Hellwig
1 sibling, 0 replies; 13+ messages in thread
From: kernel test robot @ 2020-10-22 8:53 UTC (permalink / raw)
To: Sherry Sun, hch, sudeep.dutt, ashutosh.dixit, arnd, gregkh,
kishon, lorenzo.pieralisi
Cc: kbuild-all, linux-kernel, linux-pci, linux-imx
[-- Attachment #1: Type: text/plain, Size: 4976 bytes --]
Hi Sherry,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on char-misc/char-misc-testing]
[also build test WARNING on soc/for-next linus/master v5.9 next-20201022]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Sherry-Sun/Change-vring-space-from-nomal-memory-to-dma-coherent-memory/20201022-131008
base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git f3277cbfba763cd2826396521b9296de67cf1bbc
config: i386-randconfig-s002-20201022 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0
reproduce:
# apt-get install sparse
# sparse version: v0.6.3-dirty
# https://github.com/0day-ci/linux/commit/6ae9d6d36b63c7bb8170f4c0409470d8e7101880
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Sherry-Sun/Change-vring-space-from-nomal-memory-to-dma-coherent-memory/20201022-131008
git checkout 6ae9d6d36b63c7bb8170f4c0409470d8e7101880
# save the attached .config to linux build tree
make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=i386
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
"sparse warnings: (new ones prefixed by >>)"
>> drivers/misc/mic/vop/vop_main.c:339:14: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected void *used @@ got void [noderef] __iomem * @@
>> drivers/misc/mic/vop/vop_main.c:339:14: sparse: expected void *used
>> drivers/misc/mic/vop/vop_main.c:339:14: sparse: got void [noderef] __iomem *
>> drivers/misc/mic/vop/vop_main.c:357:35: sparse: sparse: restricted __le64 degrades to integer
vim +339 drivers/misc/mic/vop/vop_main.c
289
290 /*
291 * This routine will assign vring's allocated in host/io memory. Code in
292 * virtio_ring.c however continues to access this io memory as if it were local
293 * memory without io accessors.
294 */
295 static struct virtqueue *vop_find_vq(struct virtio_device *dev,
296 unsigned index,
297 void (*callback)(struct virtqueue *vq),
298 const char *name, bool ctx)
299 {
300 struct _vop_vdev *vdev = to_vopvdev(dev);
301 struct vop_device *vpdev = vdev->vpdev;
302 struct mic_vqconfig __iomem *vqconfig;
303 struct mic_vqconfig config;
304 struct virtqueue *vq;
305 void __iomem *va;
306 struct _mic_vring_info __iomem *info;
307 void *used;
308 int vr_size, _vr_size, err, magic;
309 u8 type = ioread8(&vdev->desc->type);
310
311 if (index >= ioread8(&vdev->desc->num_vq))
312 return ERR_PTR(-ENOENT);
313
314 if (!name)
315 return ERR_PTR(-ENOENT);
316
317 /* First assign the vring's allocated in host memory */
318 vqconfig = _vop_vq_config(vdev->desc) + index;
319 memcpy_fromio(&config, vqconfig, sizeof(config));
320 _vr_size = round_up(vring_size(le16_to_cpu(config.num), MIC_VIRTIO_RING_ALIGN), 4);
321 vr_size = PAGE_ALIGN(_vr_size + sizeof(struct _mic_vring_info));
322 va = vpdev->hw_ops->remap(vpdev, le64_to_cpu(config.address), vr_size);
323 if (!va)
324 return ERR_PTR(-ENOMEM);
325 vdev->vr[index] = va;
326 memset_io(va, 0x0, _vr_size);
327
328 info = va + _vr_size;
329 magic = ioread32(&info->magic);
330
331 if (WARN(magic != MIC_MAGIC + type + index, "magic mismatch")) {
332 err = -EIO;
333 goto unmap;
334 }
335
336 vdev->used_size[index] = PAGE_ALIGN(sizeof(__u16) * 3 +
337 sizeof(struct vring_used_elem) *
338 le16_to_cpu(config.num));
> 339 used = va + PAGE_ALIGN(sizeof(struct vring_desc) * le16_to_cpu(config.num) +
340 sizeof(__u16) * (3 + le16_to_cpu(config.num)));
341 vdev->used_virt[index] = used;
342 if (!used) {
343 err = -ENOMEM;
344 dev_err(_vop_dev(vdev), "%s %d err %d\n",
345 __func__, __LINE__, err);
346 goto unmap;
347 }
348
349 vq = vop_new_virtqueue(index, le16_to_cpu(config.num), dev, ctx,
350 (void __force *)va, vop_notify, callback,
351 name, used);
352 if (!vq) {
353 err = -ENOMEM;
354 goto unmap;
355 }
356
> 357 vdev->used[index] = config.address + PAGE_ALIGN(sizeof(struct vring_desc) * le16_to_cpu(config.num) +
358 sizeof(__u16) * (3 + le16_to_cpu(config.num)));
359 writeq(vdev->used[index], &vqconfig->used_address);
360
361 vq->priv = vdev;
362 return vq;
363 unmap:
364 vpdev->hw_ops->unmap(vpdev, vdev->vr[index]);
365 return ERR_PTR(err);
366 }
367
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 36245 bytes --]
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH V3 1/4] misc: vop: change the way of allocating vring and device page
2020-10-22 5:06 ` [PATCH V3 1/4] misc: vop: change the way of allocating vring and device page Sherry Sun
2020-10-22 7:58 ` kernel test robot
@ 2020-10-23 9:25 ` Christoph Hellwig
2020-10-26 2:54 ` Sherry Sun
1 sibling, 1 reply; 13+ messages in thread
From: Christoph Hellwig @ 2020-10-23 9:25 UTC (permalink / raw)
To: Sherry Sun
Cc: hch, sudeep.dutt, ashutosh.dixit, arnd, gregkh, kishon,
lorenzo.pieralisi, linux-kernel, linux-pci, linux-imx
> static int mic_dp_init(struct mic_device *mdev)
> {
> - mdev->dp = kzalloc(MIC_DP_SIZE, GFP_KERNEL);
> + mdev->dp = dma_alloc_coherent(&mdev->pdev->dev, MIC_DP_SIZE,
> + &mdev->dp_dma_addr, GFP_KERNEL);
> if (!mdev->dp)
> return -ENOMEM;
>
> - mdev->dp_dma_addr = mic_map_single(mdev,
> - mdev->dp, MIC_DP_SIZE);
> - if (mic_map_error(mdev->dp_dma_addr)) {
> - kfree(mdev->dp);
> - dev_err(&mdev->pdev->dev, "%s %d err %d\n",
> - __func__, __LINE__, -ENOMEM);
> - return -ENOMEM;
> - }
> mdev->ops->write_spad(mdev, MIC_DPLO_SPAD, mdev->dp_dma_addr);
> mdev->ops->write_spad(mdev, MIC_DPHI_SPAD, mdev->dp_dma_addr >> 32);
> return 0;
> @@ -68,8 +62,7 @@ static int mic_dp_init(struct mic_device *mdev)
> /* Uninitialize the device page */
> static void mic_dp_uninit(struct mic_device *mdev)
> {
> - mic_unmap_single(mdev, mdev->dp_dma_addr, MIC_DP_SIZE);
> - kfree(mdev->dp);
> + dma_free_coherent(&mdev->pdev->dev, MIC_DP_SIZE, mdev->dp, mdev->dp_dma_addr);
> }
This adds an over 80 char line. Also please just kill mic_dp_init and
mic_dp_uninit and inline those into the callers.
> + vvr->buf = dma_alloc_coherent(vop_dev(vdev), VOP_INT_DMA_BUF_SIZE,
> + &vvr->buf_da, GFP_KERNEL);
Another overly long line.
> @@ -1068,7 +1049,7 @@ vop_query_offset(struct vop_vdev *vdev, unsigned long offset,
> struct vop_vringh *vvr = &vdev->vvr[i];
>
> if (offset == start) {
> - *pa = virt_to_phys(vvr->vring.va);
> + *pa = vqconfig[i].address;
vqconfig[i].address is a __le64, so this needs an endian swap.
But more importantly the caller of vop_query_offset, vop_mmap, uses
remap_pfn_range and pa. You cannot mix remap_pfn_range with DMA
coherent allocations, it can only be mmaped using dma_mmap_coherent.
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH V3 2/4] misc: vop: do not allocate and reassign the used ring
2020-10-22 5:06 ` [PATCH V3 2/4] misc: vop: do not allocate and reassign the used ring Sherry Sun
2020-10-22 8:53 ` kernel test robot
@ 2020-10-23 9:26 ` Christoph Hellwig
2020-10-26 3:04 ` Sherry Sun
1 sibling, 1 reply; 13+ messages in thread
From: Christoph Hellwig @ 2020-10-23 9:26 UTC (permalink / raw)
To: Sherry Sun
Cc: hch, sudeep.dutt, ashutosh.dixit, arnd, gregkh, kishon,
lorenzo.pieralisi, linux-kernel, linux-pci, linux-imx
On Thu, Oct 22, 2020 at 01:06:36PM +0800, Sherry Sun wrote:
> We don't need to allocate and reassign the used ring here and remove the
> used_address_updated flag.Since RC has allocated the entire vring,
> including the used ring. Simply add the corresponding offset can get the
> used ring address.
Someone needs to verify this vs the existing intel implementations.
> - used = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
> - get_order(vdev->used_size[index]));
> + used = va + PAGE_ALIGN(sizeof(struct vring_desc) * le16_to_cpu(config.num) +
This adds an over 80 char line.
> + vdev->used[index] = config.address + PAGE_ALIGN(sizeof(struct vring_desc) * le16_to_cpu(config.num) +
Again.
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH V3 4/4] misc: vop: mapping kernel memory to user space as noncached
2020-10-22 5:06 ` [PATCH V3 4/4] misc: vop: mapping kernel memory to user space as noncached Sherry Sun
@ 2020-10-23 9:28 ` Christoph Hellwig
0 siblings, 0 replies; 13+ messages in thread
From: Christoph Hellwig @ 2020-10-23 9:28 UTC (permalink / raw)
To: Sherry Sun
Cc: hch, sudeep.dutt, ashutosh.dixit, arnd, gregkh, kishon,
lorenzo.pieralisi, linux-kernel, linux-pci, linux-imx
On Thu, Oct 22, 2020 at 01:06:38PM +0800, Sherry Sun wrote:
> Mapping kernel space memory to user space as noncached, since user space
> need check the updates of avail_idx and device page flags timely.
>
> Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
> Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
> ---
> drivers/misc/mic/vop/vop_vringh.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/misc/mic/vop/vop_vringh.c b/drivers/misc/mic/vop/vop_vringh.c
> index b5612183dcb8..b75c2b713a3b 100644
> --- a/drivers/misc/mic/vop/vop_vringh.c
> +++ b/drivers/misc/mic/vop/vop_vringh.c
> @@ -1058,7 +1058,7 @@ static int vop_mmap(struct file *f, struct vm_area_struct *vma)
> }
> err = remap_pfn_range(vma, vma->vm_start + offset,
> pa >> PAGE_SHIFT, size,
> - vma->vm_page_prot);
> + pgprot_noncached(vma->vm_page_prot));
Again, memory allocated using dma_alloc_coherent can only be mapped
using dma_mmap_coherent, which will use the right attributes for the
mapping, which often are cached.
^ permalink raw reply [flat|nested] 13+ messages in thread
* RE: [PATCH V3 1/4] misc: vop: change the way of allocating vring and device page
2020-10-23 9:25 ` Christoph Hellwig
@ 2020-10-26 2:54 ` Sherry Sun
0 siblings, 0 replies; 13+ messages in thread
From: Sherry Sun @ 2020-10-26 2:54 UTC (permalink / raw)
To: Christoph Hellwig
Cc: sudeep.dutt, ashutosh.dixit, arnd, gregkh, kishon,
lorenzo.pieralisi, linux-kernel, linux-pci, dl-linux-imx
Hi Christoph,
>
> > static int mic_dp_init(struct mic_device *mdev) {
> > - mdev->dp = kzalloc(MIC_DP_SIZE, GFP_KERNEL);
> > + mdev->dp = dma_alloc_coherent(&mdev->pdev->dev, MIC_DP_SIZE,
> > + &mdev->dp_dma_addr, GFP_KERNEL);
> > if (!mdev->dp)
> > return -ENOMEM;
> >
> > - mdev->dp_dma_addr = mic_map_single(mdev,
> > - mdev->dp, MIC_DP_SIZE);
> > - if (mic_map_error(mdev->dp_dma_addr)) {
> > - kfree(mdev->dp);
> > - dev_err(&mdev->pdev->dev, "%s %d err %d\n",
> > - __func__, __LINE__, -ENOMEM);
> > - return -ENOMEM;
> > - }
> > mdev->ops->write_spad(mdev, MIC_DPLO_SPAD, mdev-
> >dp_dma_addr);
> > mdev->ops->write_spad(mdev, MIC_DPHI_SPAD, mdev-
> >dp_dma_addr >> 32);
> > return 0;
> > @@ -68,8 +62,7 @@ static int mic_dp_init(struct mic_device *mdev)
> > /* Uninitialize the device page */
> > static void mic_dp_uninit(struct mic_device *mdev) {
> > - mic_unmap_single(mdev, mdev->dp_dma_addr, MIC_DP_SIZE);
> > - kfree(mdev->dp);
> > + dma_free_coherent(&mdev->pdev->dev, MIC_DP_SIZE, mdev->dp,
> > +mdev->dp_dma_addr);
> > }
>
> This adds an over 80 char line. Also please just kill mic_dp_init and
> mic_dp_uninit and inline those into the callers.
Okay, will fix them.
>
> > + vvr->buf = dma_alloc_coherent(vop_dev(vdev),
> VOP_INT_DMA_BUF_SIZE,
> > + &vvr->buf_da, GFP_KERNEL);
>
> Another overly long line.
>
> > @@ -1068,7 +1049,7 @@ vop_query_offset(struct vop_vdev *vdev,
> unsigned long offset,
> > struct vop_vringh *vvr = &vdev->vvr[i];
> >
> > if (offset == start) {
> > - *pa = virt_to_phys(vvr->vring.va);
> > + *pa = vqconfig[i].address;
>
> vqconfig[i].address is a __le64, so this needs an endian swap.
>
> But more importantly the caller of vop_query_offset, vop_mmap, uses
> remap_pfn_range and pa. You cannot mix remap_pfn_range with DMA
> coherent allocations, it can only be mmaped using dma_mmap_coherent.
Will change to use dma_mmap_coherent in V4.
Best regards
Sherry
^ permalink raw reply [flat|nested] 13+ messages in thread
* RE: [PATCH V3 2/4] misc: vop: do not allocate and reassign the used ring
2020-10-23 9:26 ` Christoph Hellwig
@ 2020-10-26 3:04 ` Sherry Sun
2020-10-27 6:28 ` gregkh
0 siblings, 1 reply; 13+ messages in thread
From: Sherry Sun @ 2020-10-26 3:04 UTC (permalink / raw)
To: Christoph Hellwig, gregkh
Cc: sudeep.dutt, ashutosh.dixit, arnd, kishon, lorenzo.pieralisi,
linux-kernel, linux-pci, dl-linux-imx
Hi Greg & Christoph,
> Subject: Re: [PATCH V3 2/4] misc: vop: do not allocate and reassign the used
> ring
>
> On Thu, Oct 22, 2020 at 01:06:36PM +0800, Sherry Sun wrote:
> > We don't need to allocate and reassign the used ring here and remove
> > the used_address_updated flag.Since RC has allocated the entire vring,
> > including the used ring. Simply add the corresponding offset can get
> > the used ring address.
>
> Someone needs to verify this vs the existing intel implementations.
Hi Greg, @gregkh@linuxfoundation.org, sorry I don't have the Intel MIC devices so cannot test it, do you know anyone who can help test this patch changes on the Intel MIC platform? Thanks.
>
> > - used = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
> > - get_order(vdev->used_size[index]));
> > + used = va + PAGE_ALIGN(sizeof(struct vring_desc) *
> > +le16_to_cpu(config.num) +
>
> This adds an over 80 char line.
Hi Christoph, will fix it in V4, thanks.
>
> > + vdev->used[index] = config.address + PAGE_ALIGN(sizeof(struct
> > +vring_desc) * le16_to_cpu(config.num) +
>
> Again.
Best regards
Sherry
^ permalink raw reply [flat|nested] 13+ messages in thread
* Re: [PATCH V3 2/4] misc: vop: do not allocate and reassign the used ring
2020-10-26 3:04 ` Sherry Sun
@ 2020-10-27 6:28 ` gregkh
0 siblings, 0 replies; 13+ messages in thread
From: gregkh @ 2020-10-27 6:28 UTC (permalink / raw)
To: Sherry Sun
Cc: Christoph Hellwig, sudeep.dutt, ashutosh.dixit, arnd, kishon,
lorenzo.pieralisi, linux-kernel, linux-pci, dl-linux-imx
On Mon, Oct 26, 2020 at 03:04:45AM +0000, Sherry Sun wrote:
> Hi Greg & Christoph,
>
> > Subject: Re: [PATCH V3 2/4] misc: vop: do not allocate and reassign the used
> > ring
> >
> > On Thu, Oct 22, 2020 at 01:06:36PM +0800, Sherry Sun wrote:
> > > We don't need to allocate and reassign the used ring here and remove
> > > the used_address_updated flag.Since RC has allocated the entire vring,
> > > including the used ring. Simply add the corresponding offset can get
> > > the used ring address.
> >
> > Someone needs to verify this vs the existing intel implementations.
>
> Hi Greg, @gregkh@linuxfoundation.org, sorry I don't have the Intel MIC devices so cannot test it, do you know anyone who can help test this patch changes on the Intel MIC platform? Thanks.
Why not ask the authors/maintainers of that code?
greg k-h
^ permalink raw reply [flat|nested] 13+ messages in thread
end of thread, other threads:[~2020-10-27 6:28 UTC | newest]
Thread overview: 13+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-10-22 5:06 [PATCH V3 0/4] Change vring space from nomal memory to dma coherent memory Sherry Sun
2020-10-22 5:06 ` [PATCH V3 1/4] misc: vop: change the way of allocating vring and device page Sherry Sun
2020-10-22 7:58 ` kernel test robot
2020-10-23 9:25 ` Christoph Hellwig
2020-10-26 2:54 ` Sherry Sun
2020-10-22 5:06 ` [PATCH V3 2/4] misc: vop: do not allocate and reassign the used ring Sherry Sun
2020-10-22 8:53 ` kernel test robot
2020-10-23 9:26 ` Christoph Hellwig
2020-10-26 3:04 ` Sherry Sun
2020-10-27 6:28 ` gregkh
2020-10-22 5:06 ` [PATCH V3 3/4] misc: vop: simply return the saved dma address instead of virt_to_phys Sherry Sun
2020-10-22 5:06 ` [PATCH V3 4/4] misc: vop: mapping kernel memory to user space as noncached Sherry Sun
2020-10-23 9:28 ` Christoph Hellwig
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