This patches introduces SVA (Shared Virtual Addressing)
support for vDPA device. During vDPA device allocation,
vDPA device driver needs to indicate whether SVA is
supported by the device. Then vhost-vdpa bus driver
will not pin user page and transfer userspace virtual
address instead of physical address during DMA mapping.
Suggested-by: Jason Wang <jasowang@xxxxxxxxxx>
Signed-off-by: Xie Yongji <xieyongji@xxxxxxxxxxxxx>
---
drivers/vdpa/ifcvf/ifcvf_main.c | 2 +-
drivers/vdpa/mlx5/net/mlx5_vnet.c | 2 +-
drivers/vdpa/vdpa.c | 5 ++++-
drivers/vdpa/vdpa_sim/vdpa_sim.c | 3 ++-
drivers/vhost/vdpa.c | 35 +++++++++++++++++++++++------------
include/linux/vdpa.h | 10 +++++++---
6 files changed, 38 insertions(+), 19 deletions(-)
diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
index 23474af7da40..95c4601f82f5 100644
--- a/drivers/vdpa/ifcvf/ifcvf_main.c
+++ b/drivers/vdpa/ifcvf/ifcvf_main.c
@@ -439,7 +439,7 @@ static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
adapter = vdpa_alloc_device(struct ifcvf_adapter, vdpa,
dev, &ifc_vdpa_ops,
- IFCVF_MAX_QUEUE_PAIRS * 2, NULL);
+ IFCVF_MAX_QUEUE_PAIRS * 2, NULL, false);
if (adapter == NULL) {
IFCVF_ERR(pdev, "Failed to allocate vDPA structure");
return -ENOMEM;
diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 77595c81488d..05988d6907f2 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -1959,7 +1959,7 @@ static int mlx5v_probe(struct auxiliary_device *adev,
max_vqs = min_t(u32, max_vqs, MLX5_MAX_SUPPORTED_VQS);
ndev = vdpa_alloc_device(struct mlx5_vdpa_net, mvdev.vdev, mdev->device, &mlx5_vdpa_ops,
- 2 * mlx5_vdpa_max_qps(max_vqs), NULL);
+ 2 * mlx5_vdpa_max_qps(max_vqs), NULL, false);
if (IS_ERR(ndev))
return PTR_ERR(ndev);
diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
index 32bd48baffab..50cab930b2e5 100644
--- a/drivers/vdpa/vdpa.c
+++ b/drivers/vdpa/vdpa.c
@@ -72,6 +72,7 @@ static void vdpa_release_dev(struct device *d)
* @nvqs: number of virtqueues supported by this device
* @size: size of the parent structure that contains private data
* @name: name of the vdpa device; optional.
+ * @sva: indicate whether SVA (Shared Virtual Addressing) is supported
*
* Driver should use vdpa_alloc_device() wrapper macro instead of
* using this directly.
@@ -81,7 +82,8 @@ static void vdpa_release_dev(struct device *d)
*/
struct vdpa_device *__vdpa_alloc_device(struct device *parent,
const struct vdpa_config_ops *config,
- int nvqs, size_t size, const char *name)
+ int nvqs, size_t size, const char *name,
+ bool sva)
{
struct vdpa_device *vdev;
int err = -EINVAL;
@@ -108,6 +110,7 @@ struct vdpa_device *__vdpa_alloc_device(struct device *parent,
vdev->config = config;
vdev->features_valid = false;
vdev->nvqs = nvqs;
+ vdev->sva = sva;
if (name)
err = dev_set_name(&vdev->dev, "%s", name);
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index 85776e4e6749..03c796873a6b 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -367,7 +367,8 @@ static struct vdpasim *vdpasim_create(const char *name)
else
ops = &vdpasim_net_config_ops;
- vdpasim = vdpa_alloc_device(struct vdpasim, vdpa, NULL, ops, VDPASIM_VQ_NUM, name);
+ vdpasim = vdpa_alloc_device(struct vdpasim, vdpa, NULL, ops,
+ VDPASIM_VQ_NUM, name, false);
if (!vdpasim)
goto err_alloc;
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 4a241d380c40..36b6950ba37f 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -486,21 +486,25 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep,
static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last)
{
struct vhost_dev *dev = &v->vdev;
+ struct vdpa_device *vdpa = v->vdpa;
struct vhost_iotlb *iotlb = dev->iotlb;
struct vhost_iotlb_map *map;
struct page *page;
unsigned long pfn, pinned;
while ((map = vhost_iotlb_itree_first(iotlb, start, last)) != NULL) {
- pinned = map->size >> PAGE_SHIFT;
- for (pfn = map->addr >> PAGE_SHIFT;
- pinned > 0; pfn++, pinned--) {
- page = pfn_to_page(pfn);
- if (map->perm & VHOST_ACCESS_WO)
- set_page_dirty_lock(page);
- unpin_user_page(page);
+ if (!vdpa->sva) {
+ pinned = map->size >> PAGE_SHIFT;
+ for (pfn = map->addr >> PAGE_SHIFT;
+ pinned > 0; pfn++, pinned--) {
+ page = pfn_to_page(pfn);
+ if (map->perm & VHOST_ACCESS_WO)
+ set_page_dirty_lock(page);
+ unpin_user_page(page);
+ }
+ atomic64_sub(map->size >> PAGE_SHIFT,
+ &dev->mm->pinned_vm);
}
- atomic64_sub(map->size >> PAGE_SHIFT, &dev->mm->pinned_vm);
vhost_iotlb_map_free(iotlb, map);
}
}
@@ -558,13 +562,15 @@ static int vhost_vdpa_map(struct vhost_vdpa *v,
r = iommu_map(v->domain, iova, pa, size,
perm_to_iommu_flags(perm));
}
-
- if (r)
+ if (r) {
vhost_iotlb_del_range(dev->iotlb, iova, iova + size - 1);
- else
+ return r;
+ }
+
+ if (!vdpa->sva)
atomic64_add(size >> PAGE_SHIFT, &dev->mm->pinned_vm);
- return r;
+ return 0;
}
static void vhost_vdpa_unmap(struct vhost_vdpa *v, u64 iova, u64 size)
@@ -589,6 +595,7 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
struct vhost_iotlb_msg *msg)
{
struct vhost_dev *dev = &v->vdev;
+ struct vdpa_device *vdpa = v->vdpa;
struct vhost_iotlb *iotlb = dev->iotlb;
struct page **page_list;
unsigned long list_size = PAGE_SIZE / sizeof(struct page *);
@@ -607,6 +614,10 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
msg->iova + msg->size - 1))
return -EEXIST;
+ if (vdpa->sva)
+ return vhost_vdpa_map(v, msg->iova, msg->size,
+ msg->uaddr, msg->perm);
+
/* Limit the use of memory for bookkeeping */
page_list = (struct page **) __get_free_page(GFP_KERNEL);
if (!page_list)
diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index cb5a3d847af3..f86869651614 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -44,6 +44,7 @@ struct vdpa_parent_dev;
* @config: the configuration ops for this device.
* @index: device index
* @features_valid: were features initialized? for legacy guests
+ * @sva: indicate whether SVA (Shared Virtual Addressing) is supported
