scsi: core: Allow the state change from SDEV_QUIESCE to SDEV_BLOCK

The APIs scsi_host_block()/scsi_host_unblock() were recently added by
commit 2bb955840c1d ("scsi: core: add scsi_host_(block,unblock) helper
function") and so far the APIs are only used by: commit 3d3ca53b1639
("scsi: aacraid: use scsi_host_(block,unblock) to block I/O").

However, from reading the code, I think the APIs don't really work for
aacraid, because, in the resume path of hibernation, when aac_suspend() ->
scsi_host_block() is called, scsi_device_quiesce() has set the state to
SDEV_QUIESCE, so aac_suspend() -> scsi_host_block() returns -EINVAL.

Fix the issue by allowing the state change.

Link: https://lore.kernel.org/r/1587170445-50013-1-git-send-email-decui@microsoft.com
Fixes: 2bb955840c1d ("scsi: core: add scsi_host_(block,unblock) helper function")
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 47835c4b4ee05016420f07f0bf63c015879e5009..06c260f6cdae3f43fc8de4ced5d5b98a0d36bac9 100644 (file)
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2284,6 +2284,7 @@ scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state)
                switch (oldstate) {
                case SDEV_RUNNING:
                case SDEV_CREATED_BLOCK:
+               case SDEV_QUIESCE:
                case SDEV_OFFLINE:
                        break;
                default: