diff options
Diffstat (limited to 'hw/block/virtio-blk.c')
| -rw-r--r-- | hw/block/virtio-blk.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index 000c38d2a1..9546fd2919 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -33,6 +33,7 @@ VirtIOBlockReq *virtio_blk_alloc_request(VirtIOBlock *s) VirtIOBlockReq *req = g_slice_new(VirtIOBlockReq); req->dev = s; req->qiov.size = 0; + req->in_len = 0; req->next = NULL; req->mr_next = NULL; return req; @@ -54,7 +55,7 @@ static void virtio_blk_complete_request(VirtIOBlockReq *req, trace_virtio_blk_req_complete(req, status); stb_p(&req->in->status, status); - virtqueue_push(s->vq, &req->elem, req->qiov.size + sizeof(*req->in)); + virtqueue_push(s->vq, &req->elem, req->in_len); virtio_notify(vdev, s->vq); } @@ -102,6 +103,14 @@ static void virtio_blk_rw_complete(void *opaque, int ret) if (ret) { int p = virtio_ldl_p(VIRTIO_DEVICE(req->dev), &req->out.type); bool is_read = !(p & VIRTIO_BLK_T_OUT); + /* Note that memory may be dirtied on read failure. If the + * virtio request is not completed here, as is the case for + * BLOCK_ERROR_ACTION_STOP, the memory may not be copied + * correctly during live migration. While this is ugly, + * it is acceptable because the device is free to write to + * the memory until the request is completed (which will + * happen on the other side of the migration). + */ if (virtio_blk_handle_rw_error(req, -ret, is_read)) { continue; } @@ -496,6 +505,8 @@ void virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb) exit(1); } + /* We always touch the last byte, so just see how big in_iov is. */ + req->in_len = iov_size(in_iov, in_num); req->in = (void *)in_iov[in_num - 1].iov_base + in_iov[in_num - 1].iov_len - sizeof(struct virtio_blk_inhdr); |