virtio: fail adding buffer on broken queues.

Heinz points out that adding buffers to a broken virtqueue (which
should "never happen") still works.  Failing allows drivers to detect
and complain about broken devices.

Now drivers are robust, we can add this extra check.

Reported-by: Heinz Graalfs <graalfs@linux.vnet.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Rusty Russell 2014-03-13 11:23:40 +10:30
parent 9914a76617
commit 70670444c2
1 changed files with 8 additions and 3 deletions

View File

@ -204,6 +204,11 @@ static inline int virtqueue_add(struct virtqueue *_vq,
BUG_ON(data == NULL);
if (unlikely(vq->broken)) {
END_USE(vq);
return -EIO;
}
#ifdef DEBUG
{
ktime_t now = ktime_get();
@ -310,7 +315,7 @@ add_head:
* Caller must ensure we don't call this with other virtqueue operations
* at the same time (except where noted).
*
* Returns zero or a negative error (ie. ENOSPC, ENOMEM).
* Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO).
*/
int virtqueue_add_sgs(struct virtqueue *_vq,
struct scatterlist *sgs[],
@ -348,7 +353,7 @@ EXPORT_SYMBOL_GPL(virtqueue_add_sgs);
* Caller must ensure we don't call this with other virtqueue operations
* at the same time (except where noted).
*
* Returns zero or a negative error (ie. ENOSPC, ENOMEM).
* Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO).
*/
int virtqueue_add_outbuf(struct virtqueue *vq,
struct scatterlist sg[], unsigned int num,
@ -370,7 +375,7 @@ EXPORT_SYMBOL_GPL(virtqueue_add_outbuf);
* Caller must ensure we don't call this with other virtqueue operations
* at the same time (except where noted).
*
* Returns zero or a negative error (ie. ENOSPC, ENOMEM).
* Returns zero or a negative error (ie. ENOSPC, ENOMEM, EIO).
*/
int virtqueue_add_inbuf(struct virtqueue *vq,
struct scatterlist sg[], unsigned int num,