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>

diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index cb807d0ea498df3a197d0c3ed70d5548e57d97b7..2ee28266fd0704fd1e1c4c64a6f19c8d863727fd 100644 (file)
--- 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;

diff --git a/include/linux/uio.h b/include/linux/uio.h
index 1c5e453f7ea997364a4d26852a2b532ec3b8acd5..af3439f4ebf2501485f2dbbc0e71ecf2e1e00fac 100644 (file)
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -135,7 +135,6 @@ static inline void iov_iter_reexpand(struct iov_iter *i, size_t count)
 size_t csum_and_copy_to_iter(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i);
 size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i);
 
-int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len);
 int memcpy_fromiovecend(unsigned char *kdata, const struct iovec *iov,
                        int offset, int len);
 int memcpy_toiovecend(const struct iovec *v, unsigned char *kdata,

diff --git a/lib/iovec.c b/lib/iovec.c
index 2d99cb4a500634b43fad5fe176c4951795b60721..4a90875c64ae711fad4e112951fbfbf0524ad50c 100644 (file)
--- a/lib/iovec.c
+++ b/lib/iovec.c
@@ -2,31 +2,6 @@
 #include <linux/export.h>
 #include <linux/uio.h>
 
-/*
- *     Copy iovec to kernel. Returns -EFAULT on error.
- *
- *     Note: this modifies the original iovec.
- */
-
-int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len)
-{
-       while (len > 0) {
-               if (iov->iov_len) {
-                       int copy = min_t(unsigned int, len, iov->iov_len);
-                       if (copy_from_user(kdata, iov->iov_base, copy))
-                               return -EFAULT;
-                       len -= copy;
-                       kdata += copy;
-                       iov->iov_base += copy;
-                       iov->iov_len -= copy;
-               }
-               iov++;
-       }
-
-       return 0;
-}
-EXPORT_SYMBOL(memcpy_fromiovec);
-
 /*
  *     Copy kernel to iovec. Returns -EFAULT on error.
  */