[SCSI] scsi_dh_alua: fix stpg sense handling

For the stpg_endio path we are not evaluating the sense. The bug
is that

1. The error value is set to -EIO when there is sense, so we hit the first
error check and always return SCSI_DH_IO.

2. h->senselen is set to zero in submit_stpg. It is not later set to
req->sense_len like in the synchrounous exection paths, so we must
check the req->sense_len field.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 6f4d8e6f32f1..6648ffbb121a 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -232,13 +232,13 @@ static void stpg_endio(struct request *req, int error)
         struct scsi_sense_hdr sense_hdr;
         unsigned err = SCSI_DH_OK;
 
-        if (error || host_byte(req->errors) != DID_OK ||
-                        msg_byte(req->errors) != COMMAND_COMPLETE) {
+        if (host_byte(req->errors) != DID_OK ||
+            msg_byte(req->errors) != COMMAND_COMPLETE) {
                 err = SCSI_DH_IO;
                 goto done;
         }
 
-        if (h->senselen > 0) {
+        if (req->sense_len > 0) {
                 err = scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE,
                                            &sense_hdr);
                 if (!err) {
@@ -255,7 +255,9 @@ static void stpg_endio(struct request *req, int error)
                             ALUA_DH_NAME, sense_hdr.sense_key,
                             sense_hdr.asc, sense_hdr.ascq);
                 err = SCSI_DH_IO;
-        }
+        } else if (error)
+                err = SCSI_DH_IO;
+
         if (err == SCSI_DH_OK) {
                 h->state = TPGS_STATE_OPTIMIZED;
                 sdev_printk(KERN_INFO, h->sdev,