From 6fea15b01bafce2b30a32e4fcafd747c5665c16b Mon Sep 17 00:00:00 2001
From: Akinori Furuta <afuruta@m7.dion.ne.jp>
Date: Wed, 27 Oct 2010 20:39:24 +0900
Subject: [PATCH] SCSI: Take timeout value from sysfs "timeout" attr.
 To prevent ADATA SSD may hang at FLUSH_CACHE, write value to "timeout" attr greater than 30.

---
 drivers/scsi/sd.c |   27 +++++++++++++++++++++++++--
 1 files changed, 25 insertions(+), 2 deletions(-)
 mode change 100644 => 100755 drivers/scsi/sd.c

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
old mode 100644
new mode 100755
index ffa0689..ab5db46
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -426,6 +426,7 @@ static int scsi_setup_discard_cmnd(struct scsi_device *sdp, struct request *rq)
 	sector_t sector = bio->bi_sector;
 	unsigned int nr_sectors = bio_sectors(bio);
 	unsigned int len;
+	unsigned int timeout;
 	int ret;
 	struct page *page;
 
@@ -434,7 +435,17 @@ static int scsi_setup_discard_cmnd(struct scsi_device *sdp, struct request *rq)
 		nr_sectors >>= 3;
 	}
 
-	rq->timeout = SD_TIMEOUT;
+	/* Copy timeout value from request_queue. i.e. from sysfs timeout. */
+	timeout=rq->q->rq_timeout;
+	if (timeout<SD_TIMEOUT) {
+		/* Too small value. Limit smallest value tp SD_TIMEOUT. */
+		timeout=SD_TIMEOUT;
+	}
+	/* On SSD, UNMAP, WRITE SAME(16) or TRIM(ATA device) commands
+	   initiate writting and erasing on flush memory pages. So, 
+	   take timeout value from read/write timeout value.
+	*/
+	rq->timeout=timeout;
 
 	memset(rq->cmd, 0, rq->cmd_len);
 
@@ -477,7 +488,19 @@ static int scsi_setup_discard_cmnd(struct scsi_device *sdp, struct request *rq)
 
 static int scsi_setup_flush_cmnd(struct scsi_device *sdp, struct request *rq)
 {
-	rq->timeout = SD_TIMEOUT;
+	unsigned int timeout;
+	/* Copy timeout value from request_queue. i.e. from sysfs timeout. */
+	timeout=rq->q->rq_timeout;
+	if (timeout<SD_TIMEOUT) {
+		/* Too small value. Limit smallest value tp SD_TIMEOUT. */
+		timeout=SD_TIMEOUT;
+	}
+	/* On SSD, SYNCHRONIZE_CACHE or FLUSH CACHE(ATA device) commands
+	   initiate writting on flush memory pages. So, 
+	   take timeout value from read/write timeout value.
+	*/
+	rq->timeout=timeout;
+
 	rq->retries = SD_MAX_RETRIES;
 	rq->cmd[0] = SYNCHRONIZE_CACHE;
 	rq->cmd_len = 10;
-- 
1.7.2.3