On Tue, Jul 25, 2023 at 04:05:38PM -0400, Stefan Hajnoczi wrote:
On Mon, Jul 24, 2023 at 05:46:11PM +0200, Stefano Garzarella wrote:
The way the virtio-blk driver is implemented in libblkio,
it's much easier to use blkio_set_int() instead of blkio_get_int()
and have it fail right away to see if `fd` is supported by the
transport. See https://gitlab.com/libblkio/libblkio/-/merge_requests/208
The commit description is vague about what's going on here. My
understanding is:
Setting the `fd` property fails with virtio-blk-* libblkio drivers
that do not support fd passing since
https://gitlab.com/libblkio/libblkio/-/merge_requests/208.
Getting the `fd` property, on the other hand, always succeeds for
virtio-blk-* libblkio drivers even when they don't support fd passing.
This patch switches to setting the `fd` property because it is a
better mechanism for probing fd passing support than getting the `fd`
property.
Please update the commit description. Thanks!
Ack, I'll update it.
Thanks,
Stefano
Signed-off-by: Stefano Garzarella <sgarz...@redhat.com>
---
block/blkio.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/block/blkio.c b/block/blkio.c
index ca1149042a..719b19324b 100644
--- a/block/blkio.c
+++ b/block/blkio.c
@@ -665,7 +665,7 @@ static int blkio_virtio_blk_common_open(BlockDriverState
*bs,
const char *blkio_driver = bs->drv->protocol_name;
BDRVBlkioState *s = bs->opaque;
bool fd_supported = false;
- int fd, ret;
+ int ret;
if (!path) {
error_setg(errp, "missing 'path' option");
@@ -678,7 +678,7 @@ static int blkio_virtio_blk_common_open(BlockDriverState
*bs,
}
if (strcmp(blkio_driver, "virtio-blk-vhost-vdpa") == 0 &&
- blkio_get_int(s->blkio, "fd", &fd) == 0) {
+ blkio_set_int(s->blkio, "fd", -1) == 0) {
fd_supported = true;
}
@@ -688,7 +688,7 @@ static int blkio_virtio_blk_common_open(BlockDriverState
*bs,
* layer through the "/dev/fdset/N" special path.
*/
if (fd_supported) {
- int open_flags;
+ int open_flags, fd;
if (flags & BDRV_O_RDWR) {
open_flags = O_RDWR;
--
2.41.0
