[PATCH v3 03/32] cxlflash: Fix read capacity timeout

[Matthew R. Ochs]

From: Manoj Kumar <kumarmn at us.ibm.com>

The timeout value for read capacity is too small. Certain devices
may take longer to respond and thus the command may prematurely
timeout. Additionally the literal used for the timeout is stale.

Update the timeout to 30 seconds (matches the value used in sd.c)
and rework the timeout literal to a more appropriate description.

Signed-off-by: Matthew R. Ochs <mrochs at linux.vnet.ibm.com>
Signed-off-by: Manoj N. Kumar <manoj at linux.vnet.ibm.com>
Reviewed-by: Brian King <brking at linux.vnet.ibm.com>
---
 drivers/scsi/cxlflash/superpipe.c | 9 ++++-----
 drivers/scsi/cxlflash/superpipe.h | 2 +-
 drivers/scsi/cxlflash/vlun.c      | 4 ++--
 3 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/scsi/cxlflash/superpipe.c b/drivers/scsi/cxlflash/superpipe.c
index 4db15a4..4e44a48 100644
--- a/drivers/scsi/cxlflash/superpipe.c
+++ b/drivers/scsi/cxlflash/superpipe.c
@@ -296,7 +296,7 @@ static int read_cap16(struct scsi_device *sdev, struct llun_info *lli)
 	int rc = 0;
 	int result = 0;
 	int retry_cnt = 0;
-	u32 tout = (MC_DISCOVERY_TIMEOUT * HZ);
+	u32 to = CMD_TIMEOUT * HZ;
 
 retry:
 	cmd_buf = kzalloc(CMD_BUFSIZE, GFP_KERNEL);
@@ -315,8 +315,7 @@ retry:
 		retry_cnt ? "re" : "", scsi_cmd[0]);
 
 	result = scsi_execute(sdev, scsi_cmd, DMA_FROM_DEVICE, cmd_buf,
-			      CMD_BUFSIZE, sense_buf, tout, CMD_RETRIES,
-			      0, NULL);
+			      CMD_BUFSIZE, sense_buf, to, CMD_RETRIES, 0, NULL);
 
 	if (driver_byte(result) == DRIVER_SENSE) {
 		result &= ~(0xFF<<24); /* DRIVER_SENSE is not an error */
@@ -1376,8 +1375,8 @@ out_attach:
 	attach->block_size = gli->blk_len;
 	attach->mmio_size = sizeof(afu->afu_map->hosts[0].harea);
 	attach->last_lba = gli->max_lba;
-	attach->max_xfer = (sdev->host->max_sectors * MAX_SECTOR_UNIT) /
-		gli->blk_len;
+	attach->max_xfer = sdev->host->max_sectors * MAX_SECTOR_UNIT;
+	attach->max_xfer /= gli->blk_len;
 
 out:
 	attach->adap_fd = fd;
diff --git a/drivers/scsi/cxlflash/superpipe.h b/drivers/scsi/cxlflash/superpipe.h
index 3f7856b..fffb179 100644
--- a/drivers/scsi/cxlflash/superpipe.h
+++ b/drivers/scsi/cxlflash/superpipe.h
@@ -28,7 +28,7 @@ extern struct cxlflash_global global;
 */
 #define MC_CHUNK_SIZE     (1 << MC_RHT_NMASK)	/* in LBAs */
 
-#define MC_DISCOVERY_TIMEOUT 5  /* 5 secs */
+#define CMD_TIMEOUT 30  /* 30 secs */
 #define CMD_RETRIES 5   /* 5 retries for scsi_execute */
 
 #define MAX_SECTOR_UNIT  512 /* max_sector is in 512 byte multiples */
diff --git a/drivers/scsi/cxlflash/vlun.c b/drivers/scsi/cxlflash/vlun.c
index 6d6608b..68994c4 100644
--- a/drivers/scsi/cxlflash/vlun.c
+++ b/drivers/scsi/cxlflash/vlun.c
@@ -414,7 +414,7 @@ static int write_same16(struct scsi_device *sdev,
 	int ws_limit = SISLITE_MAX_WS_BLOCKS;
 	u64 offset = lba;
 	int left = nblks;
-	u32 tout = sdev->request_queue->rq_timeout;
+	u32 to = sdev->request_queue->rq_timeout;
 	struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
 	struct device *dev = &cfg->dev->dev;
 
@@ -434,7 +434,7 @@ static int write_same16(struct scsi_device *sdev,
 				   &scsi_cmd[10]);
 
 		result = scsi_execute(sdev, scsi_cmd, DMA_TO_DEVICE, cmd_buf,
-				      CMD_BUFSIZE, sense_buf, tout, CMD_RETRIES,
+				      CMD_BUFSIZE, sense_buf, to, CMD_RETRIES,
 				      0, NULL);
 		if (result) {
 			dev_err_ratelimited(dev, "%s: command failed for "
-- 
2.1.0