[PATCH 04/17] scsi_dh_alua: Improve error handling

Hannes Reinecke
2015-05-04T12:42:28Z

Improve error handling and use standard logging functions
instead of hand-crafted ones.

Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 76 +++++++++++++++++-------------
1 file changed, 42 insertions(+), 34 deletions(-)

diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index b5903eb..f5d5859 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -23,6 +23,7 @@
#include <linux/delay.h>
#include <linux/module.h>
#include <scsi/scsi.h>
+#include <scsi/scsi_dbg.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_dh.h>

@@ -138,11 +139,13 @@ static unsigned submit_rtpg(struct scsi_device *sdev, struct alua_dh_data *h,
bool rtpg_ext_hdr_req)
{
struct request *rq;
- int err = SCSI_DH_RES_TEMP_UNAVAIL;
+ int err;

rq = get_alua_req(sdev, h->buff, h->bufflen, READ);
- if (!rq)
+ if (!rq) {
+ err = DRIVER_BUSY << 24;
goto done;
+ }

/* Prepare the command. */
rq->cmd[0] = MAINTENANCE_IN;
@@ -161,12 +164,12 @@ static unsigned submit_rtpg(struct scsi_device *sdev, struct alua_dh_data *h,
rq->sense_len = h->senselen = 0;

err = blk_execute_rq(rq->q, NULL, rq, 1);
- if (err == -EIO) {
- sdev_printk(KERN_INFO, sdev,
- "%s: rtpg failed with %x\n",
- ALUA_DH_NAME, rq->errors);
+ if (err < 0) {
+ if (!rq->errors)
+ err = DID_ERROR << 16;
+ else
+ err = rq->errors;
h->senselen = rq->sense_len;
- err = SCSI_DH_IO;
}
blk_put_request(rq);
done:
@@ -174,13 +177,11 @@ done:
}

/*
- * alua_stpg - Evaluate SET TARGET GROUP STATES
+ * stpg_endio - Evaluate SET TARGET GROUP STATES
* @sdev: the device to be evaluated
* @state: the new target group state
*
- * Send a SET TARGET GROUP STATES command to the device.
- * We only have to test here if we should resubmit the command;
- * any other error is assumed as a failure.
+ * Evaluate a SET TARGET GROUP STATES command response.
*/
static void stpg_endio(struct request *req, int error)
{
@@ -195,9 +196,8 @@ static void stpg_endio(struct request *req, int error)
}

if (req->sense_len > 0) {
- err = scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE,
- &sense_hdr);
- if (!err) {
+ if (!scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE,
+ &sense_hdr)) {
err = SCSI_DH_IO;
goto done;
}
@@ -206,10 +206,9 @@ static void stpg_endio(struct request *req, int error)
err = SCSI_DH_RETRY;
goto done;
}
- sdev_printk(KERN_INFO, h->sdev,
- "%s: stpg sense code: %02x/%02x/%02x\n",
- ALUA_DH_NAME, sense_hdr.sense_key,
- sense_hdr.asc, sense_hdr.ascq);
+ sdev_printk(KERN_INFO, h->sdev, "%s: stpg failed\n",
+ ALUA_DH_NAME);
+ scsi_print_sense_hdr(h->sdev, ALUA_DH_NAME, &sense_hdr);
err = SCSI_DH_IO;
} else if (error)
err = SCSI_DH_IO;
@@ -499,7 +498,7 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
struct scsi_sense_hdr sense_hdr;
int len, k, off, valid_states = 0;
unsigned char *ucp;
- unsigned err;
+ unsigned err, retval;
bool rtpg_ext_hdr_req = 1;
unsigned long expiry, interval = 0;
unsigned int tpg_desc_tbl_off;
@@ -511,13 +510,21 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
expiry = round_jiffies_up(jiffies + h->transition_tmo * HZ);

retry:
- err = submit_rtpg(sdev, h, rtpg_ext_hdr_req);
-
- if (err == SCSI_DH_IO && h->senselen > 0) {
- err = scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE,
- &sense_hdr);
- if (!err)
- return SCSI_DH_IO;
+ retval = submit_rtpg(sdev, h, rtpg_ext_hdr_req);
+
+ if (retval) {
+ if (h->senselen == 0 ||
+ !scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE,
+ &sense_hdr)) {
+ sdev_printk(KERN_INFO, sdev,
+ "%s: rtpg failed, result %d\n",
+ ALUA_DH_NAME, retval);
+ if (driver_byte(retval) == DRIVER_BUSY)
+ err = SCSI_DH_DEV_TEMP_BUSY;
+ else
+ err = SCSI_DH_IO;
+ return err;
+ }

/*
* submit_rtpg() has failed on existing arrays
@@ -535,16 +542,17 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
}

err = alua_check_sense(sdev, &sense_hdr);
- if (err == ADD_TO_MLQUEUE && time_before(jiffies, expiry))
+ if (err == ADD_TO_MLQUEUE && time_before(jiffies, expiry)) {
+ sdev_printk(KERN_ERR, sdev, "%s: rtpg retry\n",
+ ALUA_DH_NAME);
+ scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr);
goto retry;
- sdev_printk(KERN_INFO, sdev,
- "%s: rtpg sense code %02x/%02x/%02x\n",
- ALUA_DH_NAME, sense_hdr.sense_key,
- sense_hdr.asc, sense_hdr.ascq);
- err = SCSI_DH_IO;
+ }
+ sdev_printk(KERN_ERR, sdev, "%s: rtpg failed\n",
+ ALUA_DH_NAME);
+ scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr);
+ return SCSI_DH_IO;
}
- if (err != SCSI_DH_OK)
- return err;

len = (h->buff[0] << 24) + (h->buff[1] << 16) +
(h->buff[2] << 8) + h->buff[3] + 4;
--
1.8.5.2