nbd: Add the nbd NBD_DISCONNECT_ON_CLOSE config flag.

[ Upstream commit 08ba91ee6e ]

If NBD_DISCONNECT_ON_CLOSE is set on a device, then the driver will
issue a disconnect from nbd_release if the device has no remaining
bdev->bd_openers.

Fix ret val so reconfigure with only setting the flag succeeds.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Doron Roberts-Kedes <doronrk@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Doron Roberts-Kedes
2018-06-15 14:05:32 -07:00
committed by Greg Kroah-Hartman
parent 473c7b01ff
commit b043ccf739
2 changed files with 36 additions and 7 deletions

View File

@@ -53,6 +53,9 @@ enum {
/* These are client behavior specific flags. */
#define NBD_CFLAG_DESTROY_ON_DISCONNECT (1 << 0) /* delete the nbd device on
disconnect. */
#define NBD_CFLAG_DISCONNECT_ON_CLOSE (1 << 1) /* disconnect the nbd device on
* close by last opener.
*/
/* userspace doesn't need the nbd_device structure */