[SCSI] Update the SCSI state model to allow blocking in the created state

[linux-2.6-omap-h63xx.git] / drivers / scsi / scsi_lib.c

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 88d1b5f44e59f2847bfca483a035b686e57de051..d2884bffa1b9410a11c624fc3ebf7da415220e22 100644 (file)
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -65,7 +65,7 @@ static struct scsi_host_sg_pool scsi_sg_pools[] = {
 };
 #undef SP
 
-static struct kmem_cache *scsi_sdb_cache;
+struct kmem_cache *scsi_sdb_cache;
 
 static void scsi_run_queue(struct request_queue *q);
 
@@ -787,6 +787,9 @@ void scsi_release_buffers(struct scsi_cmnd *cmd)
                kmem_cache_free(scsi_sdb_cache, bidi_sdb);
                cmd->request->next_rq->special = NULL;
        }
+
+       if (scsi_prot_sg_count(cmd))
+               scsi_free_sgtable(cmd->prot_sdb);
 }
 EXPORT_SYMBOL(scsi_release_buffers);
 
@@ -849,7 +852,7 @@ static void scsi_end_bidi_request(struct scsi_cmnd *cmd)
 void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
 {
        int result = cmd->result;
-       int this_count = scsi_bufflen(cmd);
+       int this_count;
        struct request_queue *q = cmd->device->request_queue;
        struct request *req = cmd->request;
        int error = 0;
@@ -905,6 +908,7 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
         */
        if (scsi_end_request(cmd, error, good_bytes, result == 0) == NULL)
                return;
+       this_count = blk_rq_bytes(req);
 
        /* good_bytes = 0, or (inclusive) there were leftovers and
         * result = 0, so scsi_end_request couldn't retry.
@@ -947,9 +951,14 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
                                 * 6-byte command.
                                 */
                                scsi_requeue_command(q, cmd);
-                               return;
-                       } else {
+                       } else if (sshdr.asc == 0x10) /* DIX */
+                               scsi_end_request(cmd, -EIO, this_count, 0);
+                       else
                                scsi_end_request(cmd, -EIO, this_count, 1);
+                       return;
+               case ABORTED_COMMAND:
+                       if (sshdr.asc == 0x10) { /* DIF */
+                               scsi_end_request(cmd, -EIO, this_count, 0);
                                return;
                        }
                        break;
@@ -1072,6 +1081,26 @@ int scsi_init_io(struct scsi_cmnd *cmd, gfp_t gfp_mask)
                        goto err_exit;
        }
 
+       if (blk_integrity_rq(cmd->request)) {
+               struct scsi_data_buffer *prot_sdb = cmd->prot_sdb;
+               int ivecs, count;
+
+               BUG_ON(prot_sdb == NULL);
+               ivecs = blk_rq_count_integrity_sg(cmd->request);
+
+               if (scsi_alloc_sgtable(prot_sdb, ivecs, gfp_mask)) {
+                       error = BLKPREP_DEFER;
+                       goto err_exit;
+               }
+
+               count = blk_rq_map_integrity_sg(cmd->request,
+                                               prot_sdb->table.sgl);
+               BUG_ON(unlikely(count > ivecs));
+
+               cmd->prot_sdb = prot_sdb;
+               cmd->prot_sdb->table.nents = count;
+       }
+
        return BLKPREP_OK ;
 
 err_exit:
@@ -1222,6 +1251,7 @@ int scsi_prep_state_check(struct scsi_device *sdev, struct request *req)
                        break;
                case SDEV_QUIESCE:
                case SDEV_BLOCK:
+               case SDEV_CREATED_BLOCK:
                        /*
                         * If the devices is blocked we defer normal commands.
                         */
@@ -1367,7 +1397,7 @@ static void scsi_kill_request(struct request *req, struct request_queue *q)
 
        if (unlikely(cmd == NULL)) {
                printk(KERN_CRIT "impossible request in %s.\n",
-                                __FUNCTION__);
+                                __func__);
                BUG();
        }
 
@@ -1491,12 +1521,27 @@ static void scsi_request_fn(struct request_queue *q)
                        printk(KERN_CRIT "impossible request in %s.\n"
                                         "please mail a stack trace to "
                                         "linux-scsi@vger.kernel.org\n",
-                                        __FUNCTION__);
+                                        __func__);
                        blk_dump_rq_flags(req, "foo");
                        BUG();
                }
                spin_lock(shost->host_lock);
 
+               /*
+                * We hit this when the driver is using a host wide
+                * tag map. For device level tag maps the queue_depth check
+                * in the device ready fn would prevent us from trying
+                * to allocate a tag. Since the map is a shared host resource
+                * we add the dev to the starved list so it eventually gets
+                * a run when a tag is freed.
+                */
+               if (blk_queue_tagged(q) && !blk_rq_tagged(req)) {
+                       if (list_empty(&sdev->starved_entry))
+                               list_add_tail(&sdev->starved_entry,
+                                             &shost->starved_list);
+                       goto not_ready;
+               }
+
                if (!scsi_host_queue_ready(q, shost, sdev))
                        goto not_ready;
                if (scsi_target(sdev)->single_lun) {
@@ -2020,10 +2065,13 @@ scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state)
 
        switch (state) {
        case SDEV_CREATED:
-               /* There are no legal states that come back to
-                * created.  This is the manually initialised start
-                * state */
-               goto illegal;
+               switch (oldstate) {
+               case SDEV_CREATED_BLOCK:
+                       break;
+               default:
+                       goto illegal;
+               }
+               break;
                        
        case SDEV_RUNNING:
                switch (oldstate) {
@@ -2061,8 +2109,17 @@ scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state)
 
        case SDEV_BLOCK:
                switch (oldstate) {
-               case SDEV_CREATED:
                case SDEV_RUNNING:
+               case SDEV_CREATED_BLOCK:
+                       break;
+               default:
+                       goto illegal;
+               }
+               break;
+
+       case SDEV_CREATED_BLOCK:
+               switch (oldstate) {
+               case SDEV_CREATED:
                        break;
                default:
                        goto illegal;
@@ -2350,8 +2407,12 @@ scsi_internal_device_block(struct scsi_device *sdev)
        int err = 0;
 
        err = scsi_device_set_state(sdev, SDEV_BLOCK);
-       if (err)
-               return err;
+       if (err) {
+               err = scsi_device_set_state(sdev, SDEV_CREATED_BLOCK);
+
+               if (err)
+                       return err;
+       }
 
        /* 
         * The device has transitioned to SDEV_BLOCK.  Stop the
@@ -2394,8 +2455,12 @@ scsi_internal_device_unblock(struct scsi_device *sdev)
         * and goose the device queue if successful.  
         */
        err = scsi_device_set_state(sdev, SDEV_RUNNING);
-       if (err)
-               return err;
+       if (err) {
+               err = scsi_device_set_state(sdev, SDEV_CREATED);
+
+               if (err)
+                       return err;
+       }
 
        spin_lock_irqsave(q->queue_lock, flags);
        blk_start_queue(q);
@@ -2486,7 +2551,7 @@ void *scsi_kmap_atomic_sg(struct scatterlist *sgl, int sg_count,
        if (unlikely(i == sg_count)) {
                printk(KERN_ERR "%s: Bytes in sg: %zu, requested offset %zu, "
                        "elements %d\n",
-                      __FUNCTION__, sg_len, *offset, sg_count);
+                      __func__, sg_len, *offset, sg_count);
                WARN_ON(1);
                return NULL;
        }