[PATCH v6 4/4] vdpa_sim: Implement resume vdpa op

From: sebastien . boeuf
Date: Tue Jan 03 2023 - 05:52:32 EST


From: Sebastien Boeuf <sebastien.boeuf@xxxxxxxxx>

Implement resume operation for vdpa_sim devices, so vhost-vdpa will
offer that backend feature and userspace can effectively resume the
device.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@xxxxxxxxx>
---
drivers/vdpa/vdpa_sim/vdpa_sim.c | 29 +++++++++++++++++++++++++++++
drivers/vdpa/vdpa_sim/vdpa_sim.h | 1 +
2 files changed, 30 insertions(+)

diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index b071f0d842fb..756a5db0109c 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -357,6 +357,12 @@ static void vdpasim_kick_vq(struct vdpa_device *vdpa, u16 idx)
struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx];

+ if (!vdpasim->running &&
+ (vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
+ vdpasim->pending_kick = true;
+ return;
+ }
+
if (vq->ready)
schedule_work(&vdpasim->work);
}
@@ -527,6 +533,27 @@ static int vdpasim_suspend(struct vdpa_device *vdpa)
return 0;
}

+static int vdpasim_resume(struct vdpa_device *vdpa)
+{
+ struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+ int i;
+
+ spin_lock(&vdpasim->lock);
+ vdpasim->running = true;
+
+ if (vdpasim->pending_kick) {
+ /* Process pending descriptors */
+ for (i = 0; i < vdpasim->dev_attr.nvqs; ++i)
+ vdpasim_kick_vq(vdpa, i);
+
+ vdpasim->pending_kick = 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);
@@ -717,6 +744,7 @@ static const struct vdpa_config_ops vdpasim_config_ops = {
.set_status = vdpasim_set_status,
.reset = vdpasim_reset,
.suspend = vdpasim_suspend,
+ .resume = vdpasim_resume,
.get_config_size = vdpasim_get_config_size,
.get_config = vdpasim_get_config,
.set_config = vdpasim_set_config,
@@ -750,6 +778,7 @@ static const struct vdpa_config_ops vdpasim_batch_config_ops = {
.set_status = vdpasim_set_status,
.reset = vdpasim_reset,
.suspend = vdpasim_suspend,
+ .resume = vdpasim_resume,
.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 0e78737dcc16..a745605589e2 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.h
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.h
@@ -67,6 +67,7 @@ struct vdpasim {
u64 features;
u32 groups;
bool running;
+ bool pending_kick;
/* spinlock to synchronize iommu table */
spinlock_t iommu_lock;
};
--
2.37.2

---------------------------------------------------------------------
Intel Corporation SAS (French simplified joint stock company)
Registered headquarters: "Les Montalets"- 2, rue de Paris,
92196 Meudon Cedex, France
Registration Number: 302 456 199 R.C.S. NANTERRE
Capital: 5 208 026.16 Euros

This e-mail and any attachments may contain confidential material for
the sole use of the intended recipient(s). Any review or distribution
by others is strictly prohibited. If you are not the intended
recipient, please contact the sender and delete all copies.