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, 5 insertions, 2 deletions

diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index ab3c71869be5..7f618ee5ecea 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -560,12 +560,15 @@ sdev_rd_attr (vendor, "%.8s\n");
 sdev_rd_attr (model, "%.16s\n");
 sdev_rd_attr (rev, "%.4s\n");
 
+/*
+ * TODO: can we make these symlinks to the block layer ones?
+ */
 static ssize_t
 sdev_show_timeout (struct device *dev, struct device_attribute *attr, char *buf)
 {
         struct scsi_device *sdev;
         sdev = to_scsi_device(dev);
-        return snprintf (buf, 20, "%d\n", sdev->timeout / HZ);
+        return snprintf(buf, 20, "%d\n", sdev->request_queue->rq_timeout / HZ);
 }
 
 static ssize_t
@@ -576,7 +579,7 @@ sdev_store_timeout (struct device *dev, struct device_attribute *attr,
         int timeout;
         sdev = to_scsi_device(dev);
         sscanf (buf, "%d\n", &timeout);
-        sdev->timeout = timeout * HZ;
+        blk_queue_rq_timeout(sdev->request_queue, timeout * HZ);
         return count;
 }
 static DEVICE_ATTR(timeout, S_IRUGO | S_IWUSR, sdev_show_timeout, sdev_store_timeout);