[SCSI] Derive the FLUSH_TIMEOUT from the basic I/O timeout
Rather than having a separate constant for specifying the timeout on FLUSH
operations, use the basic I/O timeout value that is already configurable
on a per target basis to derive the FLUSH timeout. Looking at the current
definitions of these timeout values, the FLUSH operation is supposed to have
a value that is twice the normal timeout value. This patch preserves this
relationship while leveraging the flexibility of specifying the I/O timeout.
Based on a prior patch by KY Srinivasan <kys@microsoft.com>
Reviewed-by: KY Srinivasan <kys@microsoft.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 3824e75..fd874b8 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -830,7 +830,7 @@
static int scsi_setup_flush_cmnd(struct scsi_device *sdp, struct request *rq)
{
- rq->timeout = SD_FLUSH_TIMEOUT;
+ rq->timeout *= SD_FLUSH_TIMEOUT_MULTIPLIER;
rq->retries = SD_MAX_RETRIES;
rq->cmd[0] = SYNCHRONIZE_CACHE;
rq->cmd_len = 10;
@@ -1434,6 +1434,8 @@
{
int retries, res;
struct scsi_device *sdp = sdkp->device;
+ const int timeout = sdp->request_queue->rq_timeout
+ * SD_FLUSH_TIMEOUT_MULTIPLIER;
struct scsi_sense_hdr sshdr;
if (!scsi_device_online(sdp))
@@ -1448,8 +1450,8 @@
* flush everything.
*/
res = scsi_execute_req_flags(sdp, cmd, DMA_NONE, NULL, 0,
- &sshdr, SD_FLUSH_TIMEOUT,
- SD_MAX_RETRIES, NULL, REQ_PM);
+ &sshdr, timeout, SD_MAX_RETRIES,
+ NULL, REQ_PM);
if (res == 0)
break;
}
diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h
index 7a049de..26895ff 100644
--- a/drivers/scsi/sd.h
+++ b/drivers/scsi/sd.h
@@ -13,7 +13,11 @@
*/
#define SD_TIMEOUT (30 * HZ)
#define SD_MOD_TIMEOUT (75 * HZ)
-#define SD_FLUSH_TIMEOUT (60 * HZ)
+/*
+ * Flush timeout is a multiplier over the standard device timeout which is
+ * user modifiable via sysfs but initially set to SD_TIMEOUT
+ */
+#define SD_FLUSH_TIMEOUT_MULTIPLIER 2
#define SD_WRITE_SAME_TIMEOUT (120 * HZ)
/*