vhost: vhost_scsi_handle_vq() should just use copy_from_user()

it has just verified that it asks no more than the length of the
first segment of iovec.

And with that the last user of stuff in lib/iovec.c is gone.
RIP.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Nicholas A. Bellinger <nab@linux-iscsi.org>
Cc: kvm@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2014-12-10 16:03:43 -05:00
parent ba7438aed9
commit 57dd8a0735
4 changed files with 2 additions and 40 deletions

View File

@ -1079,7 +1079,7 @@ vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
req_size, vq->iov[0].iov_len);
break;
}
ret = memcpy_fromiovecend(req, &vq->iov[0], 0, req_size);
ret = copy_from_user(req, vq->iov[0].iov_base, req_size);
if (unlikely(ret)) {
vq_err(vq, "Faulted on virtio_scsi_cmd_req\n");
break;

View File

@ -135,6 +135,4 @@ 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_fromiovecend(unsigned char *kdata, const struct iovec *iov,
int offset, int len);
#endif

View File

@ -24,7 +24,7 @@ obj-y += lockref.o
obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \
gcd.o lcm.o list_sort.o uuid.o flex_array.o iovec.o clz_ctz.o \
gcd.o lcm.o list_sort.o uuid.o flex_array.o clz_ctz.o \
bsearch.o find_last_bit.o find_next_bit.o llist.o memweight.o kfifo.o \
percpu-refcount.o percpu_ida.o rhashtable.o reciprocal_div.o
obj-y += string_helpers.o

View File

@ -1,36 +0,0 @@
#include <linux/uaccess.h>
#include <linux/export.h>
#include <linux/uio.h>
/*
* Copy iovec to kernel. Returns -EFAULT on error.
*/
int memcpy_fromiovecend(unsigned char *kdata, const struct iovec *iov,
int offset, int len)
{
/* No data? Done! */
if (len == 0)
return 0;
/* Skip over the finished iovecs */
while (offset >= iov->iov_len) {
offset -= iov->iov_len;
iov++;
}
while (len > 0) {
u8 __user *base = iov->iov_base + offset;
int copy = min_t(unsigned int, len, iov->iov_len - offset);
offset = 0;
if (copy_from_user(kdata, base, copy))
return -EFAULT;
len -= copy;
kdata += copy;
iov++;
}
return 0;
}
EXPORT_SYMBOL(memcpy_fromiovecend);