[PATCH vhost v4 06/15] vdpa: Track device suspended state

Dragos Tatulea
2023-12-19T18:09:45Z

Set vdpa device suspended state on successful suspend. Clear it on
successful resume and reset.

The state will be locked by the vhost_vdpa mutex. The mutex is taken
during suspend, resume and reset in vhost_vdpa_unlocked_ioctl. The
exception is vhost_vdpa_open which does a device reset but that should
be safe because it can only happen before the other ops.

Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Suggested-by: Eugenio Pérez <eperezma@redhat.com>
---
drivers/vhost/vdpa.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index b4e8ddf86485..00b4fa8e89f2 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -59,6 +59,7 @@ struct vhost_vdpa {
int in_batch;
struct vdpa_iova_range range;
u32 batch_asid;
+ bool suspended;
};

static DEFINE_IDA(vhost_vdpa_ida);
@@ -232,6 +233,8 @@ static int _compat_vdpa_reset(struct vhost_vdpa *v)
struct vdpa_device *vdpa = v->vdpa;
u32 flags = 0;

+ v->suspended = false;
+
if (v->vdev.vqs) {
flags |= !vhost_backend_has_feature(v->vdev.vqs[0],
VHOST_BACKEND_F_IOTLB_PERSIST) ?
@@ -590,11 +593,16 @@ static long vhost_vdpa_suspend(struct vhost_vdpa *v)
{
struct vdpa_device *vdpa = v->vdpa;
const struct vdpa_config_ops *ops = vdpa->config;
+ int ret;

if (!ops->suspend)
return -EOPNOTSUPP;

- return ops->suspend(vdpa);
+ ret = ops->suspend(vdpa);
+ if (!ret)
+ v->suspended = true;
+
+ return ret;
}

/* After a successful return of this ioctl the device resumes processing
@@ -605,11 +613,16 @@ static long vhost_vdpa_resume(struct vhost_vdpa *v)
{
struct vdpa_device *vdpa = v->vdpa;
const struct vdpa_config_ops *ops = vdpa->config;
+ int ret;

if (!ops->resume)
return -EOPNOTSUPP;

- return ops->resume(vdpa);
+ ret = ops->resume(vdpa);
+ if (!ret)
+ v->suspended = false;
+
+ return ret;
}

static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
--
2.43.0