---
drivers/vdpa/vdpa_sim/vdpa_sim.c | 67 ++++++++++++++++++++++++++++++++
drivers/vdpa/vdpa_sim/vdpa_sim.h | 3 ++
2 files changed, 70 insertions(+)
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index cb88891b44a8..5a8c820b179f 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -39,6 +39,8 @@ MODULE_PARM_DESC(max_iotlb_entries,
#define VDPASIM_QUEUE_ALIGN PAGE_SIZE
#define VDPASIM_QUEUE_MAX 256
#define VDPASIM_VENDOR_ID 0
+#define VDPASIM_VRING_POLL_PERIOD 100 /* ms */
+#define VDPASIM_NOTIFY_DEFVAL 0xffff
static struct vdpasim *vdpa_to_sim(struct vdpa_device *vdpa)
{
@@ -245,6 +247,28 @@ static const struct dma_map_ops vdpasim_dma_ops = {
static const struct vdpa_config_ops vdpasim_config_ops;
static const struct vdpa_config_ops vdpasim_batch_config_ops;
+static void vdpasim_notify_work(struct work_struct *work)
+{
+ struct vdpasim *vdpasim;
+ u16 *val;
+
+ vdpasim = container_of(work, struct vdpasim, notify_work.work);
+
+ if (!(vdpasim->status & VIRTIO_CONFIG_S_DRIVER_OK))
+ goto out;
+
+ if (!vdpasim->running)
+ goto out;
+
+ val = (u16 *)vdpasim->notify;
+ if (xchg(val, VDPASIM_NOTIFY_DEFVAL) != VDPASIM_NOTIFY_DEFVAL)
+ schedule_work(&vdpasim->work);
+
+out:
+ schedule_delayed_work(&vdpasim->notify_work,
+ msecs_to_jiffies(VDPASIM_VRING_POLL_PERIOD));
+}
+
struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *dev_attr,
const struct vdpa_dev_set_config *config)
{
@@ -286,6 +310,13 @@ struct vdpasim *vdpasim_create(struct vdpasim_dev_attr
*dev_attr,
set_dma_ops(dev, &vdpasim_dma_ops);
vdpasim->vdpa.mdev = dev_attr->mgmt_dev;
+ INIT_DELAYED_WORK(&vdpasim->notify_work, vdpasim_notify_work);
+
+ vdpasim->notify = (u16 *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
+ if (!vdpasim->notify)
+ goto err_iommu;
+ WRITE_ONCE(*vdpasim->notify, VDPASIM_NOTIFY_DEFVAL);
+
vdpasim->config = kzalloc(dev_attr->config_size, GFP_KERNEL);
if (!vdpasim->config)
goto err_iommu;
@@ -320,6 +351,13 @@ struct vdpasim *vdpasim_create(struct vdpasim_dev_attr
*dev_attr,
vdpasim->vdpa.dma_dev = dev;
+ /*
+ * Start periodic (every 100ms) notify work, it won't introduce
+ * any overhead if the device is not started.
+ */
+ schedule_delayed_work(&vdpasim->notify_work,
+ msecs_to_jiffies(VDPASIM_VRING_POLL_PERIOD));
+
return vdpasim;
err_iommu:
@@ -671,11 +709,34 @@ static int vdpasim_dma_unmap(struct vdpa_device *vdpa,
unsigned int asid,
return 0;
}
+static pgprot_t vdpasim_get_vq_notification_pgprot(struct vdpa_device *vdpa,
+ u16 qid, pgprot_t prot)
+{
+ /*
+ * We use normal RAM pages to emulate the vq notification area, so
+ * just keep the pgprot as it mmaped.
+ */
+ return prot;
+}
+
+static struct vdpa_notification_area
+vdpasim_get_vq_notification(struct vdpa_device *vdpa, u16 qid)
+{
+ struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+ struct vdpa_notification_area notify;
+
+ notify.addr = virt_to_phys((void *)vdpasim->notify);
+ notify.size = PAGE_SIZE;
+
+ return notify;
+}
+
static void vdpasim_free(struct vdpa_device *vdpa)
{
struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
int i;
+ cancel_delayed_work_sync(&vdpasim->notify_work);
cancel_work_sync(&vdpasim->work);
for (i = 0; i < vdpasim->dev_attr.nvqs; i++) {
@@ -694,6 +755,8 @@ static void vdpasim_free(struct vdpa_device *vdpa)
kfree(vdpasim->iommu);
kfree(vdpasim->vqs);
kfree(vdpasim->config);
+ if (vdpasim->notify)
+ free_page((unsigned long)vdpasim->notify);
}
static const struct vdpa_config_ops vdpasim_config_ops = {
@@ -705,6 +768,8 @@ static const struct vdpa_config_ops vdpasim_config_ops = {
.get_vq_ready = vdpasim_get_vq_ready,
.set_vq_state = vdpasim_set_vq_state,
.get_vq_state = vdpasim_get_vq_state,
+ .get_vq_notification = vdpasim_get_vq_notification,
+ .get_vq_notification_pgprot = vdpasim_get_vq_notification_pgprot,
.get_vq_align = vdpasim_get_vq_align,
.get_vq_group = vdpasim_get_vq_group,
.get_device_features = vdpasim_get_device_features,
@@ -738,6 +803,8 @@ static const struct vdpa_config_ops
vdpasim_batch_config_ops = {
.get_vq_ready = vdpasim_get_vq_ready,
.set_vq_state = vdpasim_set_vq_state,
.get_vq_state = vdpasim_get_vq_state,
+ .get_vq_notification = vdpasim_get_vq_notification,
+ .get_vq_notification_pgprot = vdpasim_get_vq_notification_pgprot,
.get_vq_align = vdpasim_get_vq_align,
.get_vq_group = vdpasim_get_vq_group,
.get_device_features = vdpasim_get_device_features,
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.h b/drivers/vdpa/vdpa_sim/vdpa_sim.h
index 0e78737dcc16..786e902de0b2 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.h
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.h
@@ -69,6 +69,9 @@ struct vdpasim {
bool running;
/* spinlock to synchronize iommu table */
spinlock_t iommu_lock;
+ /* dummy notify page */
+ u16 *notify;
+ struct delayed_work notify_work;
};
struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *attr,
