diff options
| author | Takahiro Yasui <tyasui@redhat.com> | 2009-04-29 12:13:02 -0400 |
|---|---|---|
| committer | James Bottomley <James.Bottomley@HansenPartnership.com> | 2009-05-23 15:44:05 -0500 |
| commit | 5c10e63c943b4c67561ddc6bf61e01d4141f881f (patch) | |
| tree | 7b71f601bcf852159bae15a2cf6caa038d74e27d /drivers/scsi/scsi_lib.c | |
| parent | b0d428adebe9f1232c72bf4c686a6f0eed047cc2 (diff) | |
[SCSI] limit state transitions in scsi_internal_device_unblock
scsi timeout on two or more devices may cause extremely long execution
time for user applications because SDEV_OFFLINE state is changed to
SDEV_RUNNING state during scsi error recovery procedures triggered by
a bus reset or a host reset of scsi LLD, and scsi timeout can happens
on the same devices many times.
This happens because scsi_internal_device_unblock() changes device's
state to SDEV_RUNNING even if a device in other states than SDEV_BLOCK,
while the following two transitions are required in this function.
SDEV_BLOCK -> SDEV_RUNNING
SDEV_CREATED_BLOCK -> SDEV_CREATED
Otherwise, it returns -EINVAL.
Signed-off-by: Takahiro Yasui <tyasui@redhat.com>
[matthew@wil.cx: supplied rewritten base for patch]
Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Diffstat (limited to 'drivers/scsi/scsi_lib.c')
| -rw-r--r-- | drivers/scsi/scsi_lib.c | 14 |
1 files changed, 6 insertions, 8 deletions
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index bb218c8b6e9..27dbf2e8e34 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -2441,20 +2441,18 @@ int scsi_internal_device_unblock(struct scsi_device *sdev) { struct request_queue *q = sdev->request_queue; - int err; unsigned long flags; /* * Try to transition the scsi device to SDEV_RUNNING * and goose the device queue if successful. */ - err = scsi_device_set_state(sdev, SDEV_RUNNING); - if (err) { - err = scsi_device_set_state(sdev, SDEV_CREATED); - - if (err) - return err; - } + if (sdev->sdev_state == SDEV_BLOCK) + sdev->sdev_state = SDEV_RUNNING; + else if (sdev->sdev_state == SDEV_CREATED_BLOCK) + sdev->sdev_state = SDEV_CREATED; + else + return -EINVAL; spin_lock_irqsave(q->queue_lock, flags); blk_start_queue(q); |