Implement suspend operation for vdpa_sim devices, so vhost-vdpa will offer
that backend feature and userspace can effectively suspend the device.
This is a must before getting virtqueue indexes (base) for live migration,
since the device could modify them after userland gets them. There are
individual ways to perform that action for some devices
(VHOST_NET_SET_BACKEND, VHOST_VSOCK_SET_RUNNING, ...) but there was no
way to perform it for any vhost device (and, in particular, vhost-vdpa).
After a successful return of ioctl the device must not process more virtqueue
descriptors. The device can answer to read or writes of config fields as if it
were not suspended. In particular, writing to "queue_enable" with a value of 1
will not make the device start processing virtqueue buffers.
In the future, we will provide features similar to
VHOST_USER_GET_INFLIGHT_FD so the device can save pending operations.
Applied on top of [1] branch after removing the old commits.
Comments are welcome.
v7:
* Remove ioctl leftover argument and update doc accordingly.
v6:
* Remove the resume operation, making the ioctl simpler. We can always add
another ioctl for VM_STOP/VM_RESUME operation later.
* s/stop/suspend/ to differentiate more from reset.
* Clarify scope of the suspend operation.
v5:
* s/not stop/resume/ in doc.
v4:
* Replace VHOST_STOP to VHOST_VDPA_STOP in vhost ioctl switch case too.
v3:
* s/VHOST_STOP/VHOST_VDPA_STOP/
* Add documentation and requirements of the ioctl above its definition.
v2:
* Replace raw _F_STOP with BIT_ULL(_F_STOP).
* Fix obtaining of stop ioctl arg (it was not obtained but written).
* Add stop to vdpa_sim_blk.
[1] git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git
Eugenio Pérez (4):
vdpa: Add suspend operation
vhost-vdpa: introduce SUSPEND backend feature bit
vhost-vdpa: uAPI to suspend the device
vdpa_sim: Implement suspend vdpa op
drivers/vdpa/vdpa_sim/vdpa_sim.c | 14 +++++++++++
drivers/vdpa/vdpa_sim/vdpa_sim.h | 1 +
drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 3 +++
drivers/vdpa/vdpa_sim/vdpa_sim_net.c | 3 +++
drivers/vhost/vdpa.c | 35 +++++++++++++++++++++++++++-
include/linux/vdpa.h | 4 ++++
include/uapi/linux/vhost.h | 9 +++++++
include/uapi/linux/vhost_types.h | 2 ++
8 files changed, 70 insertions(+), 1 deletion(-)
--
2.31.1
Userland knows if it can suspend the device or not by checking this feature
bit.
It's only offered if the vdpa driver backend implements the suspend()
operation callback, and to offer it or userland to ack it if the backend
does not offer that callback is an error.
Signed-off-by: Eugenio Pérez <[email protected]>
Message-Id: <[email protected]>
Signed-off-by: Michael S. Tsirkin <[email protected]>
---
drivers/vhost/vdpa.c | 16 +++++++++++++++-
include/uapi/linux/vhost_types.h | 2 ++
2 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 23dcbfdfa13b..3d636e192061 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -347,6 +347,14 @@ static long vhost_vdpa_set_config(struct vhost_vdpa *v,
return 0;
}
+static bool vhost_vdpa_can_suspend(const struct vhost_vdpa *v)
+{
+ struct vdpa_device *vdpa = v->vdpa;
+ const struct vdpa_config_ops *ops = vdpa->config;
+
+ return ops->suspend;
+}
+
static long vhost_vdpa_get_features(struct vhost_vdpa *v, u64 __user *featurep)
{
struct vdpa_device *vdpa = v->vdpa;
@@ -577,7 +585,11 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep,
if (cmd == VHOST_SET_BACKEND_FEATURES) {
if (copy_from_user(&features, featurep, sizeof(features)))
return -EFAULT;
- if (features & ~VHOST_VDPA_BACKEND_FEATURES)
+ if (features & ~(VHOST_VDPA_BACKEND_FEATURES |
+ BIT_ULL(VHOST_BACKEND_F_SUSPEND)))
+ return -EOPNOTSUPP;
+ if ((features & BIT_ULL(VHOST_BACKEND_F_SUSPEND)) &&
+ !vhost_vdpa_can_suspend(v))
return -EOPNOTSUPP;
vhost_set_backend_features(&v->vdev, features);
return 0;
@@ -628,6 +640,8 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep,
break;
case VHOST_GET_BACKEND_FEATURES:
features = VHOST_VDPA_BACKEND_FEATURES;
+ if (vhost_vdpa_can_suspend(v))
+ features |= BIT_ULL(VHOST_BACKEND_F_SUSPEND);
if (copy_to_user(featurep, &features, sizeof(features)))
r = -EFAULT;
break;
diff --git a/include/uapi/linux/vhost_types.h b/include/uapi/linux/vhost_types.h
index 634cee485abb..1bdd6e363f4c 100644
--- a/include/uapi/linux/vhost_types.h
+++ b/include/uapi/linux/vhost_types.h
@@ -161,5 +161,7 @@ struct vhost_vdpa_iova_range {
* message
*/
#define VHOST_BACKEND_F_IOTLB_ASID 0x3
+/* Device can be suspended */
+#define VHOST_BACKEND_F_SUSPEND 0x4
#endif
--
2.31.1
The ioctl adds support for suspending the device from userspace.
This is a must before getting virtqueue indexes (base) for live migration,
since the device could modify them after userland gets them. There are
individual ways to perform that action for some devices
(VHOST_NET_SET_BACKEND, VHOST_VSOCK_SET_RUNNING, ...) but there was no
way to perform it for any vhost device (and, in particular, vhost-vdpa).
After a successful return of the ioctl call the device must not process
more virtqueue descriptors. The device can answer to read or writes of
config fields as if it were not suspended. In particular, writing to
"queue_enable" with a value of 1 will not make the device start
processing buffers of the virtqueue.
Signed-off-by: Eugenio Pérez <[email protected]>
Message-Id: <[email protected]>
Signed-off-by: Michael S. Tsirkin <[email protected]>
---
v7: Delete argument to ioctl, unused
---
drivers/vhost/vdpa.c | 19 +++++++++++++++++++
include/uapi/linux/vhost.h | 9 +++++++++
2 files changed, 28 insertions(+)
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 3d636e192061..7fa671ac4bdf 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -478,6 +478,22 @@ static long vhost_vdpa_get_vqs_count(struct vhost_vdpa *v, u32 __user *argp)
return 0;
}
+/* After a successful return of ioctl the device must not process more
+ * virtqueue descriptors. The device can answer to read or writes of config
+ * fields as if it were not suspended. In particular, writing to "queue_enable"
+ * with a value of 1 will not make the device start processing buffers.
+ */
+static long vhost_vdpa_suspend(struct vhost_vdpa *v)
+{
+ struct vdpa_device *vdpa = v->vdpa;
+ const struct vdpa_config_ops *ops = vdpa->config;
+
+ if (!ops->suspend)
+ return -EOPNOTSUPP;
+
+ return ops->suspend(vdpa);
+}
+
static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
void __user *argp)
{
@@ -654,6 +670,9 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep,
case VHOST_VDPA_GET_VQS_COUNT:
r = vhost_vdpa_get_vqs_count(v, argp);
break;
+ case VHOST_VDPA_SUSPEND:
+ r = vhost_vdpa_suspend(v);
+ break;
default:
r = vhost_dev_ioctl(&v->vdev, cmd, argp);
if (r == -ENOIOCTLCMD)
diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h
index cab645d4a645..f9f115a7c75b 100644
--- a/include/uapi/linux/vhost.h
+++ b/include/uapi/linux/vhost.h
@@ -171,4 +171,13 @@
#define VHOST_VDPA_SET_GROUP_ASID _IOW(VHOST_VIRTIO, 0x7C, \
struct vhost_vring_state)
+/* Suspend a device so it does not process virtqueue requests anymore
+ *
+ * After the return of ioctl the device must preserve all the necessary state
+ * (the virtqueue vring base plus the possible device specific states) that is
+ * required for restoring in the future. The device must not change its
+ * configuration after that point.
+ */
+#define VHOST_VDPA_SUSPEND _IO(VHOST_VIRTIO, 0x7D)
+
#endif
--
2.31.1
Implement suspend operation for vdpa_sim devices, so vhost-vdpa will
offer that backend feature and userspace can effectively suspend the
device.
This is a must before get virtqueue indexes (base) for live migration,
since the device could modify them after userland gets them. There are
individual ways to perform that action for some devices
(VHOST_NET_SET_BACKEND, VHOST_VSOCK_SET_RUNNING, ...) but there was no
way to perform it for any vhost device (and, in particular, vhost-vdpa).
Reviewed-by: Stefano Garzarella <[email protected]>
Signed-off-by: Eugenio Pérez <[email protected]>
Message-Id: <[email protected]>
Signed-off-by: Michael S. Tsirkin <[email protected]>
---
v7: Delete leftover resume code
---
drivers/vdpa/vdpa_sim/vdpa_sim.c | 14 ++++++++++++++
drivers/vdpa/vdpa_sim/vdpa_sim.h | 1 +
drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 3 +++
drivers/vdpa/vdpa_sim/vdpa_sim_net.c | 3 +++
4 files changed, 21 insertions(+)
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index 0f2865899647..79a50edf8998 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -107,6 +107,7 @@ static void vdpasim_do_reset(struct vdpasim *vdpasim)
for (i = 0; i < vdpasim->dev_attr.nas; i++)
vhost_iotlb_reset(&vdpasim->iommu[i]);
+ vdpasim->running = true;
spin_unlock(&vdpasim->iommu_lock);
vdpasim->features = 0;
@@ -505,6 +506,17 @@ static int vdpasim_reset(struct vdpa_device *vdpa)
return 0;
}
+static int vdpasim_suspend(struct vdpa_device *vdpa)
+{
+ struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+
+ spin_lock(&vdpasim->lock);
+ vdpasim->running = false;
+ spin_unlock(&vdpasim->lock);
+
+ return 0;
+}
+
static size_t vdpasim_get_config_size(struct vdpa_device *vdpa)
{
struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
@@ -694,6 +706,7 @@ static const struct vdpa_config_ops vdpasim_config_ops = {
.get_status = vdpasim_get_status,
.set_status = vdpasim_set_status,
.reset = vdpasim_reset,
+ .suspend = vdpasim_suspend,
.get_config_size = vdpasim_get_config_size,
.get_config = vdpasim_get_config,
.set_config = vdpasim_set_config,
@@ -726,6 +739,7 @@ static const struct vdpa_config_ops vdpasim_batch_config_ops = {
.get_status = vdpasim_get_status,
.set_status = vdpasim_set_status,
.reset = vdpasim_reset,
+ .suspend = vdpasim_suspend,
.get_config_size = vdpasim_get_config_size,
.get_config = vdpasim_get_config,
.set_config = vdpasim_set_config,
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.h b/drivers/vdpa/vdpa_sim/vdpa_sim.h
index 622782e92239..061986f30911 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.h
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.h
@@ -66,6 +66,7 @@ struct vdpasim {
u32 generation;
u64 features;
u32 groups;
+ bool running;
/* spinlock to synchronize iommu table */
spinlock_t iommu_lock;
};
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
index 42d401d43911..bcdb1982c378 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
@@ -204,6 +204,9 @@ static void vdpasim_blk_work(struct work_struct *work)
if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK))
goto out;
+ if (!vdpasim->running)
+ goto out;
+
for (i = 0; i < VDPASIM_BLK_VQ_NUM; i++) {
struct vdpasim_virtqueue *vq = &vdpasim->vqs[i];
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
index 5125976a4df8..886449e88502 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim_net.c
@@ -154,6 +154,9 @@ static void vdpasim_net_work(struct work_struct *work)
spin_lock(&vdpasim->lock);
+ if (!vdpasim->running)
+ goto out;
+
if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK))
goto out;
--
2.31.1
On Wed, Aug 10, 2022 at 07:15:08PM +0200, Eugenio P?rez wrote:
> Implement suspend operation for vdpa_sim devices, so vhost-vdpa will offer
> that backend feature and userspace can effectively suspend the device.
>
> This is a must before getting virtqueue indexes (base) for live migration,
> since the device could modify them after userland gets them. There are
> individual ways to perform that action for some devices
> (VHOST_NET_SET_BACKEND, VHOST_VSOCK_SET_RUNNING, ...) but there was no
> way to perform it for any vhost device (and, in particular, vhost-vdpa).
>
> After a successful return of ioctl the device must not process more virtqueue
> descriptors. The device can answer to read or writes of config fields as if it
> were not suspended. In particular, writing to "queue_enable" with a value of 1
> will not make the device start processing virtqueue buffers.
>
> In the future, we will provide features similar to
> VHOST_USER_GET_INFLIGHT_FD so the device can save pending operations.
>
> Applied on top of [1] branch after removing the old commits.
Except, I can't really do this without invaliding all testing.
Can't you post an incremental patch?
> Comments are welcome.
>
> v7:
> * Remove ioctl leftover argument and update doc accordingly.
> v6:
> * Remove the resume operation, making the ioctl simpler. We can always add
> another ioctl for VM_STOP/VM_RESUME operation later.
> * s/stop/suspend/ to differentiate more from reset.
> * Clarify scope of the suspend operation.
>
> v5:
> * s/not stop/resume/ in doc.
>
> v4:
> * Replace VHOST_STOP to VHOST_VDPA_STOP in vhost ioctl switch case too.
>
> v3:
> * s/VHOST_STOP/VHOST_VDPA_STOP/
> * Add documentation and requirements of the ioctl above its definition.
>
> v2:
> * Replace raw _F_STOP with BIT_ULL(_F_STOP).
> * Fix obtaining of stop ioctl arg (it was not obtained but written).
> * Add stop to vdpa_sim_blk.
>
> [1] git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git
>
> Eugenio P?rez (4):
> vdpa: Add suspend operation
> vhost-vdpa: introduce SUSPEND backend feature bit
> vhost-vdpa: uAPI to suspend the device
> vdpa_sim: Implement suspend vdpa op
>
> drivers/vdpa/vdpa_sim/vdpa_sim.c | 14 +++++++++++
> drivers/vdpa/vdpa_sim/vdpa_sim.h | 1 +
> drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 3 +++
> drivers/vdpa/vdpa_sim/vdpa_sim_net.c | 3 +++
> drivers/vhost/vdpa.c | 35 +++++++++++++++++++++++++++-
> include/linux/vdpa.h | 4 ++++
> include/uapi/linux/vhost.h | 9 +++++++
> include/uapi/linux/vhost_types.h | 2 ++
> 8 files changed, 70 insertions(+), 1 deletion(-)
>
> --
> 2.31.1
>
On Wed, Aug 10, 2022 at 9:20 PM Michael S. Tsirkin <[email protected]> wrote:
>
> On Wed, Aug 10, 2022 at 07:15:08PM +0200, Eugenio Pérez wrote:
> > Implement suspend operation for vdpa_sim devices, so vhost-vdpa will offer
> > that backend feature and userspace can effectively suspend the device.
> >
> > This is a must before getting virtqueue indexes (base) for live migration,
> > since the device could modify them after userland gets them. There are
> > individual ways to perform that action for some devices
> > (VHOST_NET_SET_BACKEND, VHOST_VSOCK_SET_RUNNING, ...) but there was no
> > way to perform it for any vhost device (and, in particular, vhost-vdpa).
> >
> > After a successful return of ioctl the device must not process more virtqueue
> > descriptors. The device can answer to read or writes of config fields as if it
> > were not suspended. In particular, writing to "queue_enable" with a value of 1
> > will not make the device start processing virtqueue buffers.
> >
> > In the future, we will provide features similar to
> > VHOST_USER_GET_INFLIGHT_FD so the device can save pending operations.
> >
> > Applied on top of [1] branch after removing the old commits.
>
> Except, I can't really do this without invaliding all testing.
> Can't you post an incremental patch?
>
Oops, sorry.
I can send it for doc and internal code. But is it ok to remove an
ioctl arg with incremental patches?
Thanks!
> > Comments are welcome.
> >
> > v7:
> > * Remove ioctl leftover argument and update doc accordingly.
>
> > v6:
> > * Remove the resume operation, making the ioctl simpler. We can always add
> > another ioctl for VM_STOP/VM_RESUME operation later.
> > * s/stop/suspend/ to differentiate more from reset.
> > * Clarify scope of the suspend operation.
> >
> > v5:
> > * s/not stop/resume/ in doc.
> >
> > v4:
> > * Replace VHOST_STOP to VHOST_VDPA_STOP in vhost ioctl switch case too.
> >
> > v3:
> > * s/VHOST_STOP/VHOST_VDPA_STOP/
> > * Add documentation and requirements of the ioctl above its definition.
> >
> > v2:
> > * Replace raw _F_STOP with BIT_ULL(_F_STOP).
> > * Fix obtaining of stop ioctl arg (it was not obtained but written).
> > * Add stop to vdpa_sim_blk.
> >
> > [1] git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git
> >
> > Eugenio Pérez (4):
> > vdpa: Add suspend operation
> > vhost-vdpa: introduce SUSPEND backend feature bit
> > vhost-vdpa: uAPI to suspend the device
> > vdpa_sim: Implement suspend vdpa op
> >
> > drivers/vdpa/vdpa_sim/vdpa_sim.c | 14 +++++++++++
> > drivers/vdpa/vdpa_sim/vdpa_sim.h | 1 +
> > drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 3 +++
> > drivers/vdpa/vdpa_sim/vdpa_sim_net.c | 3 +++
> > drivers/vhost/vdpa.c | 35 +++++++++++++++++++++++++++-
> > include/linux/vdpa.h | 4 ++++
> > include/uapi/linux/vhost.h | 9 +++++++
> > include/uapi/linux/vhost_types.h | 2 ++
> > 8 files changed, 70 insertions(+), 1 deletion(-)
> >
> > --
> > 2.31.1
> >
>
On Wed, Aug 10, 2022 at 07:15:11PM +0200, Eugenio P?rez wrote:
> The ioctl adds support for suspending the device from userspace.
>
> This is a must before getting virtqueue indexes (base) for live migration,
> since the device could modify them after userland gets them. There are
> individual ways to perform that action for some devices
> (VHOST_NET_SET_BACKEND, VHOST_VSOCK_SET_RUNNING, ...) but there was no
> way to perform it for any vhost device (and, in particular, vhost-vdpa).
>
> After a successful return of the ioctl call the device must not process
> more virtqueue descriptors. The device can answer to read or writes of
> config fields as if it were not suspended. In particular, writing to
> "queue_enable" with a value of 1 will not make the device start
> processing buffers of the virtqueue.
>
> Signed-off-by: Eugenio P?rez <[email protected]>
> Message-Id: <[email protected]>
> Signed-off-by: Michael S. Tsirkin <[email protected]>
You are not supposed to include upstream maintainer's signoff
like this.
> ---
> v7: Delete argument to ioctl, unused
> ---
> drivers/vhost/vdpa.c | 19 +++++++++++++++++++
> include/uapi/linux/vhost.h | 9 +++++++++
> 2 files changed, 28 insertions(+)
>
> diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
> index 3d636e192061..7fa671ac4bdf 100644
> --- a/drivers/vhost/vdpa.c
> +++ b/drivers/vhost/vdpa.c
> @@ -478,6 +478,22 @@ static long vhost_vdpa_get_vqs_count(struct vhost_vdpa *v, u32 __user *argp)
> return 0;
> }
>
> +/* After a successful return of ioctl the device must not process more
> + * virtqueue descriptors. The device can answer to read or writes of config
> + * fields as if it were not suspended. In particular, writing to "queue_enable"
> + * with a value of 1 will not make the device start processing buffers.
> + */
> +static long vhost_vdpa_suspend(struct vhost_vdpa *v)
> +{
> + struct vdpa_device *vdpa = v->vdpa;
> + const struct vdpa_config_ops *ops = vdpa->config;
> +
> + if (!ops->suspend)
> + return -EOPNOTSUPP;
> +
> + return ops->suspend(vdpa);
> +}
> +
> static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
> void __user *argp)
> {
> @@ -654,6 +670,9 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep,
> case VHOST_VDPA_GET_VQS_COUNT:
> r = vhost_vdpa_get_vqs_count(v, argp);
> break;
> + case VHOST_VDPA_SUSPEND:
> + r = vhost_vdpa_suspend(v);
> + break;
> default:
> r = vhost_dev_ioctl(&v->vdev, cmd, argp);
> if (r == -ENOIOCTLCMD)
> diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h
> index cab645d4a645..f9f115a7c75b 100644
> --- a/include/uapi/linux/vhost.h
> +++ b/include/uapi/linux/vhost.h
> @@ -171,4 +171,13 @@
> #define VHOST_VDPA_SET_GROUP_ASID _IOW(VHOST_VIRTIO, 0x7C, \
> struct vhost_vring_state)
>
> +/* Suspend a device so it does not process virtqueue requests anymore
> + *
> + * After the return of ioctl the device must preserve all the necessary state
> + * (the virtqueue vring base plus the possible device specific states) that is
> + * required for restoring in the future. The device must not change its
> + * configuration after that point.
> + */
> +#define VHOST_VDPA_SUSPEND _IO(VHOST_VIRTIO, 0x7D)
> +
> #endif
> --
> 2.31.1
On Thu, Aug 11, 2022 at 10:29 AM Michael S. Tsirkin <[email protected]> wrote:
>
> On Wed, Aug 10, 2022 at 07:15:11PM +0200, Eugenio Pérez wrote:
> > The ioctl adds support for suspending the device from userspace.
> >
> > This is a must before getting virtqueue indexes (base) for live migration,
> > since the device could modify them after userland gets them. There are
> > individual ways to perform that action for some devices
> > (VHOST_NET_SET_BACKEND, VHOST_VSOCK_SET_RUNNING, ...) but there was no
> > way to perform it for any vhost device (and, in particular, vhost-vdpa).
> >
> > After a successful return of the ioctl call the device must not process
> > more virtqueue descriptors. The device can answer to read or writes of
> > config fields as if it were not suspended. In particular, writing to
> > "queue_enable" with a value of 1 will not make the device start
> > processing buffers of the virtqueue.
> >
> > Signed-off-by: Eugenio Pérez <[email protected]>
> > Message-Id: <[email protected]>
> > Signed-off-by: Michael S. Tsirkin <[email protected]>
>
> You are not supposed to include upstream maintainer's signoff
> like this.
>
I'm very sorry, I modified the commits in your vhost branch and I left
the signoff (and message-id) lines by mistake.
> > ---
> > v7: Delete argument to ioctl, unused
> > ---
> > drivers/vhost/vdpa.c | 19 +++++++++++++++++++
> > include/uapi/linux/vhost.h | 9 +++++++++
> > 2 files changed, 28 insertions(+)
> >
> > diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
> > index 3d636e192061..7fa671ac4bdf 100644
> > --- a/drivers/vhost/vdpa.c
> > +++ b/drivers/vhost/vdpa.c
> > @@ -478,6 +478,22 @@ static long vhost_vdpa_get_vqs_count(struct vhost_vdpa *v, u32 __user *argp)
> > return 0;
> > }
> >
> > +/* After a successful return of ioctl the device must not process more
> > + * virtqueue descriptors. The device can answer to read or writes of config
> > + * fields as if it were not suspended. In particular, writing to "queue_enable"
> > + * with a value of 1 will not make the device start processing buffers.
> > + */
> > +static long vhost_vdpa_suspend(struct vhost_vdpa *v)
> > +{
> > + struct vdpa_device *vdpa = v->vdpa;
> > + const struct vdpa_config_ops *ops = vdpa->config;
> > +
> > + if (!ops->suspend)
> > + return -EOPNOTSUPP;
> > +
> > + return ops->suspend(vdpa);
> > +}
> > +
> > static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
> > void __user *argp)
> > {
> > @@ -654,6 +670,9 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep,
> > case VHOST_VDPA_GET_VQS_COUNT:
> > r = vhost_vdpa_get_vqs_count(v, argp);
> > break;
> > + case VHOST_VDPA_SUSPEND:
> > + r = vhost_vdpa_suspend(v);
> > + break;
> > default:
> > r = vhost_dev_ioctl(&v->vdev, cmd, argp);
> > if (r == -ENOIOCTLCMD)
> > diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h
> > index cab645d4a645..f9f115a7c75b 100644
> > --- a/include/uapi/linux/vhost.h
> > +++ b/include/uapi/linux/vhost.h
> > @@ -171,4 +171,13 @@
> > #define VHOST_VDPA_SET_GROUP_ASID _IOW(VHOST_VIRTIO, 0x7C, \
> > struct vhost_vring_state)
> >
> > +/* Suspend a device so it does not process virtqueue requests anymore
> > + *
> > + * After the return of ioctl the device must preserve all the necessary state
> > + * (the virtqueue vring base plus the possible device specific states) that is
> > + * required for restoring in the future. The device must not change its
> > + * configuration after that point.
> > + */
> > +#define VHOST_VDPA_SUSPEND _IO(VHOST_VIRTIO, 0x7D)
> > +
> > #endif
> > --
> > 2.31.1
>