diff options
| author |   Bart Van Assche <bart.vanassche@sandisk.com> | 2017-06-02 14:21:55 -0700 |
|---|---|---|
| committer |   Martin K. Petersen <martin.petersen@oracle.com> | 2017-06-12 20:55:59 -0400 |
| commit | 0db6ca8a5e1ea585795db3643ec7d50fc8cb1aff (patch) | |
| tree | 52ae689dcddbc9155a840617c405de2b377de618 /drivers/scsi/sd.c | |
| parent | scsi: Create two versions of scsi_internal_device_unblock() (diff) | |
| download | linux-dev-0db6ca8a5e1ea585795db3643ec7d50fc8cb1aff.tar.xz linux-dev-0db6ca8a5e1ea585795db3643ec7d50fc8cb1aff.zip | |
scsi: Protect SCSI device state changes with a mutex
Serializing SCSI device state changes avoids that two state changes can
occur concurrently, e.g. the state changes in scsi_target_block() and
__scsi_remove_device(). This serialization is essential to make patch
"Make __scsi_remove_device go straight from BLOCKED to DEL" work
reliably.
Enable this mechanism for all scsi_target_*block() callers but not for
the scsi_internal_device_unblock() calls from the mpt3sas driver because
that driver can call scsi_internal_device_unblock() from atomic context.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'drivers/scsi/sd.c')
| -rw-r--r-- | drivers/scsi/sd.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index b6bb4e0ce0e3..53b6d72c214d 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -1818,8 +1818,9 @@ static void sd_eh_reset(struct scsi_cmnd *scmd) static int sd_eh_action(struct scsi_cmnd *scmd, int eh_disp) { struct scsi_disk *sdkp = scsi_disk(scmd->request->rq_disk); + struct scsi_device *sdev = scmd->device; - if (!scsi_device_online(scmd->device) || + if (!scsi_device_online(sdev) || !scsi_medium_access_command(scmd) || host_byte(scmd->result) != DID_TIME_OUT || eh_disp != SUCCESS) @@ -1845,7 +1846,9 @@ static int sd_eh_action(struct scsi_cmnd *scmd, int eh_disp) if (sdkp->medium_access_timed_out >= sdkp->max_medium_access_timeouts) { scmd_printk(KERN_ERR, scmd, "Medium access timeout failure. Offlining disk!\n"); - scsi_device_set_state(scmd->device, SDEV_OFFLINE); + mutex_lock(&sdev->state_mutex); + scsi_device_set_state(sdev, SDEV_OFFLINE); + mutex_unlock(&sdev->state_mutex); return SUCCESS; } |