Commit aad9a1ce authored by Al Viro's avatar Al Viro
Browse files

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: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 8ae5e030

drivers/vhost/vhost.c

+4 −2
Original line number Diff line number Diff line
@@ -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;

include/linux/uio.h

+0 −1
Original line number Diff line number Diff line
@@ -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,

lib/iovec.c

+0 −25
Original line number Diff line number Diff line
@@ -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.

 */