block: unify request timeout handling

Right now SCSI and others do their own command timeout handling.
Move those bits to the block layer.

Instead of having a timer per command, we try to be a bit more clever
and simply have one per-queue. This avoids the overhead of having to
tear down and setup a timer for each command, so it will result in a lot
less timer fiddling.

Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 13 insertions, 4 deletions

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 62307bd794a9..e7686500e9dd 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1181,7 +1181,6 @@ int scsi_setup_blk_pc_cmnd(struct scsi_device *sdev, struct request *req)
         
         cmd->transfersize = req->data_len;
         cmd->allowed = req->retries;
-        cmd->timeout_per_command = req->timeout;
         return BLKPREP_OK;
 }
 EXPORT_SYMBOL(scsi_setup_blk_pc_cmnd);
@@ -1416,17 +1415,26 @@ static void scsi_kill_request(struct request *req, struct request_queue *q)
         spin_unlock(shost->host_lock);
         spin_lock(sdev->request_queue->queue_lock);
 
-        __scsi_done(cmd);
+        blk_complete_request(req);
 }
 
 static void scsi_softirq_done(struct request *rq)
 {
-        struct scsi_cmnd *cmd = rq->completion_data;
-        unsigned long wait_for = (cmd->allowed + 1) * cmd->timeout_per_command;
+        struct scsi_cmnd *cmd = rq->special;
+        unsigned long wait_for = (cmd->allowed + 1) * rq->timeout;
         int disposition;
 
         INIT_LIST_HEAD(&cmd->eh_entry);
 
+        /*
+         * Set the serial numbers back to zero
+         */
+        cmd->serial_number = 0;
+
+        atomic_inc(&cmd->device->iodone_cnt);
+        if (cmd->result)
+                atomic_inc(&cmd->device->ioerr_cnt);
+
         disposition = scsi_decide_disposition(cmd);
         if (disposition != SUCCESS &&
             time_before(cmd->jiffies_at_alloc + wait_for, jiffies)) {
@@ -1675,6 +1683,7 @@ struct request_queue *scsi_alloc_queue(struct scsi_device *sdev)
 
         blk_queue_prep_rq(q, scsi_prep_fn);
         blk_queue_softirq_done(q, scsi_softirq_done);
+        blk_queue_rq_timed_out(q, scsi_times_out);
         return q;
 }