scsi: centralize command re-queueing in scsi_dispatch_fn

Make sure we only have the logic for requeing commands in one place.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Webb Scales <webbnh@hp.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Robert Elliott <elliott@hp.com>
This commit is contained in:
Christoph Hellwig 2014-01-22 18:39:04 +01:00
parent de3e8bf331
commit d0d3bbf96e
2 changed files with 18 additions and 26 deletions

View File

@ -645,9 +645,7 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
* returns an immediate error upwards, and signals
* that the device is no longer present */
cmd->result = DID_NO_CONNECT << 16;
scsi_done(cmd);
/* return 0 (because the command has been processed) */
goto out;
goto done;
}
/* Check to see if the scsi lld made this device blocked. */
@ -659,17 +657,9 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
* occur until the device transitions out of the
* suspend state.
*/
scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY);
SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
"queuecommand : device blocked\n"));
/*
* NOTE: rtn is still zero here because we don't need the
* queue to be plugged on return (it's already stopped)
*/
goto out;
return SCSI_MLQUEUE_DEVICE_BUSY;
}
/*
@ -693,20 +683,19 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
"cdb_size=%d host->max_cmd_len=%d\n",
cmd->cmd_len, cmd->device->host->max_cmd_len));
cmd->result = (DID_ABORT << 16);
scsi_done(cmd);
goto out;
goto done;
}
if (unlikely(host->shost_state == SHOST_DEL)) {
cmd->result = (DID_NO_CONNECT << 16);
scsi_done(cmd);
} else {
trace_scsi_dispatch_cmd_start(cmd);
cmd->scsi_done = scsi_done;
rtn = host->hostt->queuecommand(host, cmd);
goto done;
}
trace_scsi_dispatch_cmd_start(cmd);
cmd->scsi_done = scsi_done;
rtn = host->hostt->queuecommand(host, cmd);
if (rtn) {
trace_scsi_dispatch_cmd_error(cmd, rtn);
if (rtn != SCSI_MLQUEUE_DEVICE_BUSY &&
@ -715,12 +704,12 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
SCSI_LOG_MLQUEUE(3, scmd_printk(KERN_INFO, cmd,
"queuecommand : request rejected\n"));
scsi_queue_insert(cmd, rtn);
}
out:
return rtn;
done:
scsi_done(cmd);
return 0;
}
/**

View File

@ -1557,9 +1557,12 @@ static void scsi_request_fn(struct request_queue *q)
* Dispatch the command to the low-level driver.
*/
rtn = scsi_dispatch_cmd(cmd);
spin_lock_irq(q->queue_lock);
if (rtn)
if (rtn) {
scsi_queue_insert(cmd, rtn);
spin_lock_irq(q->queue_lock);
goto out_delay;
}
spin_lock_irq(q->queue_lock);
}
return;
@ -1579,7 +1582,7 @@ static void scsi_request_fn(struct request_queue *q)
blk_requeue_request(q, req);
sdev->device_busy--;
out_delay:
if (sdev->device_busy == 0)
if (sdev->device_busy == 0 && !scsi_device_blocked(sdev))
blk_delay_queue(q, SCSI_QUEUE_DELAY);
}