virtio-blk: Correct bug in support for flexible descriptor layout

Without this correction, only a three descriptor layout is accepted, and
requests with just two descriptors are not completed and no error message is
displayed.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Marc Marí <marc.mari.barcelo@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Marc Marí 2014-08-12 13:41:51 +02:00 committed by Stefan Hajnoczi
parent 220c1a2fad
commit a83ceea8ff

View File

@ -404,19 +404,19 @@ void virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb)
* NB: per existing s/n string convention the string is
* terminated by '\0' only when shorter than buffer.
*/
strncpy(req->elem.in_sg[0].iov_base,
s->blk.serial ? s->blk.serial : "",
MIN(req->elem.in_sg[0].iov_len, VIRTIO_BLK_ID_BYTES));
const char *serial = s->blk.serial ? s->blk.serial : "";
size_t size = MIN(strlen(serial) + 1,
MIN(iov_size(in_iov, in_num),
VIRTIO_BLK_ID_BYTES));
iov_from_buf(in_iov, in_num, 0, serial, size);
virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
virtio_blk_free_request(req);
} else if (type & VIRTIO_BLK_T_OUT) {
qemu_iovec_init_external(&req->qiov, &req->elem.out_sg[1],
req->elem.out_num - 1);
qemu_iovec_init_external(&req->qiov, iov, out_num);
virtio_blk_handle_write(req, mrb);
} else if (type == VIRTIO_BLK_T_IN || type == VIRTIO_BLK_T_BARRIER) {
/* VIRTIO_BLK_T_IN is 0, so we can't just & it. */
qemu_iovec_init_external(&req->qiov, &req->elem.in_sg[0],
req->elem.in_num - 1);
qemu_iovec_init_external(&req->qiov, in_iov, in_num);
virtio_blk_handle_read(req);
} else {
virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP);