[PATCH v13 09/13] vdpa: factor out vhost_vdpa_pa_map() and vhost_vdpa_pa_unmap()

Xie Yongji
2021-08-31T10:38:09Z

The upcoming patch is going to support VA mapping/unmapping.
So let's factor out the logic of PA mapping/unmapping firstly
to make the code more readable.

Suggested-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Acked-by: Jason Wang <jasowang@redhat.com>
---
drivers/vhost/vdpa.c | 55 +++++++++++++++++++++++++++++++++-------------------
1 file changed, 35 insertions(+), 20 deletions(-)

diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index ba030150b4b6..49a1f45ccef8 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -504,7 +504,7 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep,
return r;
}

-static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last)
+static void vhost_vdpa_pa_unmap(struct vhost_vdpa *v, u64 start, u64 last)
{
struct vhost_dev *dev = &v->vdev;
struct vhost_iotlb *iotlb = dev->iotlb;
@@ -526,6 +526,11 @@ static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last)
}
}

+static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last)
+{
+ return vhost_vdpa_pa_unmap(v, start, last);
+}
+
static void vhost_vdpa_iotlb_free(struct vhost_vdpa *v)
{
struct vhost_dev *dev = &v->vdev;
@@ -606,38 +611,28 @@ static void vhost_vdpa_unmap(struct vhost_vdpa *v, u64 iova, u64 size)
}
}

-static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
- struct vhost_iotlb_msg *msg)
+static int vhost_vdpa_pa_map(struct vhost_vdpa *v,
+ u64 iova, u64 size, u64 uaddr, u32 perm)
{
struct vhost_dev *dev = &v->vdev;
- struct vhost_iotlb *iotlb = dev->iotlb;
struct page **page_list;
unsigned long list_size = PAGE_SIZE / sizeof(struct page *);
unsigned int gup_flags = FOLL_LONGTERM;
unsigned long npages, cur_base, map_pfn, last_pfn = 0;
unsigned long lock_limit, sz2pin, nchunks, i;
- u64 iova = msg->iova;
+ u64 start = iova;
long pinned;
int ret = 0;

- if (msg->iova < v->range.first || !msg->size ||
- msg->iova > U64_MAX - msg->size + 1 ||
- msg->iova + msg->size - 1 > v->range.last)
- return -EINVAL;
-
- if (vhost_iotlb_itree_first(iotlb, msg->iova,
- msg->iova + msg->size - 1))
- return -EEXIST;
-
/* Limit the use of memory for bookkeeping */
page_list = (struct page **) __get_free_page(GFP_KERNEL);
if (!page_list)
return -ENOMEM;

- if (msg->perm & VHOST_ACCESS_WO)
+ if (perm & VHOST_ACCESS_WO)
gup_flags |= FOLL_WRITE;

- npages = PAGE_ALIGN(msg->size + (iova & ~PAGE_MASK)) >> PAGE_SHIFT;
+ npages = PAGE_ALIGN(size + (iova & ~PAGE_MASK)) >> PAGE_SHIFT;
if (!npages) {
ret = -EINVAL;
goto free;
@@ -651,7 +646,7 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
goto unlock;
}

- cur_base = msg->uaddr & PAGE_MASK;
+ cur_base = uaddr & PAGE_MASK;
iova &= PAGE_MASK;
nchunks = 0;

@@ -682,7 +677,7 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
csize = (last_pfn - map_pfn + 1) << PAGE_SHIFT;
ret = vhost_vdpa_map(v, iova, csize,
map_pfn << PAGE_SHIFT,
- msg->perm);
+ perm);
if (ret) {
/*
* Unpin the pages that are left unmapped
@@ -711,7 +706,7 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,

/* Pin the rest chunk */
ret = vhost_vdpa_map(v, iova, (last_pfn - map_pfn + 1) << PAGE_SHIFT,
- map_pfn << PAGE_SHIFT, msg->perm);
+ map_pfn << PAGE_SHIFT, perm);
out:
if (ret) {
if (nchunks) {
@@ -730,13 +725,33 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
for (pfn = map_pfn; pfn <= last_pfn; pfn++)
unpin_user_page(pfn_to_page(pfn));
}
- vhost_vdpa_unmap(v, msg->iova, msg->size);
+ vhost_vdpa_unmap(v, start, size);
}
unlock:
mmap_read_unlock(dev->mm);
free:
free_page((unsigned long)page_list);
return ret;
+
+}
+
+static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
+ struct vhost_iotlb_msg *msg)
+{
+ struct vhost_dev *dev = &v->vdev;
+ struct vhost_iotlb *iotlb = dev->iotlb;
+
+ if (msg->iova < v->range.first || !msg->size ||
+ msg->iova > U64_MAX - msg->size + 1 ||
+ msg->iova + msg->size - 1 > v->range.last)
+ return -EINVAL;
+
+ if (vhost_iotlb_itree_first(iotlb, msg->iova,
+ msg->iova + msg->size - 1))
+ return -EEXIST;
+
+ return vhost_vdpa_pa_map(v, msg->iova, msg->size, msg->uaddr,
+ msg->perm);
}

static int vhost_vdpa_process_iotlb_msg(struct vhost_dev *dev,
--
2.11.0