scsi_dh_alua: switch to scsi_execute_req_flags()

All commands are issued synchronously, so no need to open-code
scsi_execute_req_flags() anymore. And we can get rid of the
static sense code structure element. scsi_execute_req_flags()
will be setting REQ_QUIET and REQ_PREEMPT, but that is
perfectly fine as we're evaluating and logging any errors
ourselves and we really need to send the command even if
the device is quiesced.

Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index b2a2a771badc678fe6157c83ca568ae47e5377b9..73df60e83e4d552c4d81c805384d6f0857630569 100644 (file)
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -75,7 +75,6 @@ struct alua_dh_data {
        unsigned char           *buff;
        int                     bufflen;
        unsigned char           transition_tmo;
-       unsigned char           sense[SCSI_SENSE_BUFFERSIZE];
        struct scsi_device      *sdev;
        activate_complete       callback_fn;
        void                    *callback_data;
@@ -101,71 +100,30 @@ static int realloc_buffer(struct alua_dh_data *h, unsigned len)
        return 0;
 }
 
-static struct request *get_alua_req(struct scsi_device *sdev,
-                                   void *buffer, unsigned buflen, int rw)
-{
-       struct request *rq;
-       struct request_queue *q = sdev->request_queue;
-
-       rq = blk_get_request(q, rw, GFP_NOIO);
-
-       if (IS_ERR(rq)) {
-               sdev_printk(KERN_INFO, sdev,
-                           "%s: blk_get_request failed\n", __func__);
-               return NULL;
-       }
-       blk_rq_set_block_pc(rq);
-
-       if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_NOIO)) {
-               blk_put_request(rq);
-               sdev_printk(KERN_INFO, sdev,
-                           "%s: blk_rq_map_kern failed\n", __func__);
-               return NULL;
-       }
-
-       rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
-                        REQ_FAILFAST_DRIVER;
-       rq->retries = ALUA_FAILOVER_RETRIES;
-       rq->timeout = ALUA_FAILOVER_TIMEOUT * HZ;
-
-       return rq;
-}
-
 /*
  * submit_rtpg - Issue a REPORT TARGET GROUP STATES command
  * @sdev: sdev the command should be sent to
  */
-static unsigned submit_rtpg(struct scsi_device *sdev, unsigned char *buff,
-                           int bufflen, unsigned char *sense, int flags)
+static int submit_rtpg(struct scsi_device *sdev, unsigned char *buff,
+                      int bufflen, struct scsi_sense_hdr *sshdr, int flags)
 {
-       struct request *rq;
-       int err = 0;
-
-       rq = get_alua_req(sdev, buff, bufflen, READ);
-       if (!rq) {
-               err = DRIVER_BUSY << 24;
-               goto done;
-       }
+       u8 cdb[COMMAND_SIZE(MAINTENANCE_IN)];
+       int req_flags = REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
+               REQ_FAILFAST_DRIVER;
 
        /* Prepare the command. */
-       rq->cmd[0] = MAINTENANCE_IN;
+       memset(cdb, 0x0, COMMAND_SIZE(MAINTENANCE_IN));
+       cdb[0] = MAINTENANCE_IN;
        if (!(flags & ALUA_RTPG_EXT_HDR_UNSUPP))
-               rq->cmd[1] = MI_REPORT_TARGET_PGS | MI_EXT_HDR_PARAM_FMT;
+               cdb[1] = MI_REPORT_TARGET_PGS | MI_EXT_HDR_PARAM_FMT;
        else
-               rq->cmd[1] = MI_REPORT_TARGET_PGS;
-       put_unaligned_be32(bufflen, &rq->cmd[6]);
-       rq->cmd_len = COMMAND_SIZE(MAINTENANCE_IN);
-
-       rq->sense = sense;
-       memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
-       rq->sense_len = 0;
-
-       blk_execute_rq(rq->q, NULL, rq, 1);
-       if (rq->errors)
-               err = rq->errors;
-       blk_put_request(rq);
-done:
-       return err;
+               cdb[1] = MI_REPORT_TARGET_PGS;
+       put_unaligned_be32(bufflen, &cdb[6]);
+
+       return scsi_execute_req_flags(sdev, cdb, DMA_FROM_DEVICE,
+                                     buff, bufflen, sshdr,
+                                     ALUA_FAILOVER_TIMEOUT * HZ,
+                                     ALUA_FAILOVER_RETRIES, NULL, req_flags);
 }
 
 /*
@@ -175,40 +133,30 @@ done:
  * to 'active/optimized' and let the array firmware figure out
  * the states of the remaining groups.
  */
-static unsigned submit_stpg(struct scsi_device *sdev, int group_id,
-                           unsigned char *sense)
+static int submit_stpg(struct scsi_device *sdev, int group_id,
+                      struct scsi_sense_hdr *sshdr)
 {
-       struct request *rq;
+       u8 cdb[COMMAND_SIZE(MAINTENANCE_OUT)];
        unsigned char stpg_data[8];
        int stpg_len = 8;
-       int err = 0;
+       int req_flags = REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
+               REQ_FAILFAST_DRIVER;
 
        /* Prepare the data buffer */
        memset(stpg_data, 0, stpg_len);
        stpg_data[4] = TPGS_STATE_OPTIMIZED & 0x0f;
        put_unaligned_be16(group_id, &stpg_data[6]);
 
-       rq = get_alua_req(sdev, stpg_data, stpg_len, WRITE);
-       if (!rq)
-               return DRIVER_BUSY << 24;
-
        /* Prepare the command. */
-       rq->cmd[0] = MAINTENANCE_OUT;
-       rq->cmd[1] = MO_SET_TARGET_PGS;
-       put_unaligned_be32(stpg_len, &rq->cmd[6]);
-       rq->cmd_len = COMMAND_SIZE(MAINTENANCE_OUT);
-
-       rq->sense = sense;
-       memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
-       rq->sense_len = 0;
-
-       blk_execute_rq(rq->q, NULL, rq, 1);
-       if (rq->errors)
-               err = rq->errors;
-
-       blk_put_request(rq);
-
-       return err;
+       memset(cdb, 0x0, COMMAND_SIZE(MAINTENANCE_OUT));
+       cdb[0] = MAINTENANCE_OUT;
+       cdb[1] = MO_SET_TARGET_PGS;
+       put_unaligned_be32(stpg_len, &cdb[6]);
+
+       return scsi_execute_req_flags(sdev, cdb, DMA_TO_DEVICE,
+                                     stpg_data, stpg_len,
+                                     sshdr, ALUA_FAILOVER_TIMEOUT * HZ,
+                                     ALUA_FAILOVER_RETRIES, NULL, req_flags);
 }
 
 /*
@@ -398,14 +346,14 @@ 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:
-       retval = submit_rtpg(sdev, h->buff, h->bufflen, h->sense, h->flags);
+       retval = submit_rtpg(sdev, h->buff, h->bufflen, &sense_hdr, h->flags);
+
        if (retval) {
-               if (!scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE,
-                                         &sense_hdr)) {
+               if (!scsi_sense_valid(&sense_hdr)) {
                        sdev_printk(KERN_INFO, sdev,
                                    "%s: rtpg failed, result %d\n",
                                    ALUA_DH_NAME, retval);
-                       if (driver_byte(retval) == DRIVER_BUSY)
+                       if (driver_byte(retval) == DRIVER_ERROR)
                                return SCSI_DH_DEV_TEMP_BUSY;
                        return SCSI_DH_IO;
                }
@@ -568,15 +516,14 @@ static unsigned alua_stpg(struct scsi_device *sdev, struct alua_dh_data *h)
                            ALUA_DH_NAME, h->state);
                return SCSI_DH_NOSYS;
        }
-       retval = submit_stpg(sdev, h->group_id, h->sense);
+       retval = submit_stpg(sdev, h->group_id, &sense_hdr);
 
        if (retval) {
-               if (!scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE,
-                                         &sense_hdr)) {
+               if (!scsi_sense_valid(&sense_hdr)) {
                        sdev_printk(KERN_INFO, sdev,
                                    "%s: stpg failed, result %d",
                                    ALUA_DH_NAME, retval);
-                       if (driver_byte(retval) == DRIVER_BUSY)
+                       if (driver_byte(retval) == DRIVER_ERROR)
                                return SCSI_DH_DEV_TEMP_BUSY;
                } else {
                        sdev_printk(KERN_INFO, h->sdev, "%s: stpg failed\n",