vhost: switch vhost get_indirect() to iov_iter, kill memcpy_fromiovec()

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: kvm@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 4 insertions, 2 deletions

diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index cb807d0ea498..2ee28266fd07 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -1125,6 +1125,7 @@ static int get_indirect(struct vhost_virtqueue *vq,
         struct vring_desc desc;
         unsigned int i = 0, count, found = 0;
         u32 len = vhost32_to_cpu(vq, indirect->len);
+        struct iov_iter from;
         int ret;
 
         /* Sanity check */
@@ -1142,6 +1143,7 @@ static int get_indirect(struct vhost_virtqueue *vq,
                 vq_err(vq, "Translation failure %d in indirect.\n", ret);
                 return ret;
         }
+        iov_iter_init(&from, READ, vq->indirect, ret, len);
 
         /* We will use the result as an address to read from, so most
          * architectures only need a compiler barrier here. */
@@ -1164,8 +1166,8 @@ static int get_indirect(struct vhost_virtqueue *vq,
                                i, count);
                         return -EINVAL;
                 }
-                if (unlikely(memcpy_fromiovec((unsigned char *)&desc,
-                                              vq->indirect, sizeof desc))) {
+                if (unlikely(copy_from_iter(&desc, sizeof(desc), &from) !=
+                             sizeof(desc))) {
                         vq_err(vq, "Failed indirect descriptor: idx %d, %zx\n",
                                i, (size_t)vhost64_to_cpu(vq, indirect->addr) + i * sizeof desc);
                         return -EINVAL;