Merge branch 'post-2.6.15' of git://brick.kernel.dk/data/git/linux-2.6-block

Manual fixup for merge with Jens' "Suspend support for libata", commit
ID 9b847548.
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Documentation/block/biodoc.txt

@@ -263,14 +263,8 @@ A flag in the bio structure, BIO_BARRIER is used to identify a barrier i/o.
 The generic i/o scheduler would make sure that it places the barrier request and
 all other requests coming after it after all the previous requests in the
 queue. Barriers may be implemented in different ways depending on the
-driver. A SCSI driver for example could make use of ordered tags to
-preserve the necessary ordering with a lower impact on throughput. For IDE
-this might be two sync cache flush: a pre and post flush when encountering
-a barrier write.
-
-There is a provision for queues to indicate what kind of barriers they
-can provide. This is as of yet unmerged, details will be added here once it
-is in the kernel.
+driver. For more details regarding I/O barriers, please read barrier.txt
+in this directory.
 
 1.2.2 Request Priority/Latency
 

block/as-iosched.c

@@ -182,6 +182,9 @@ struct as_rq {
 
 static kmem_cache_t *arq_pool;
 
+static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq);
+static void as_antic_stop(struct as_data *ad);
+
 /*
  * IO Context helper functions
  */
@@ -370,7 +373,7 @@ static struct as_rq *as_find_first_arq(struct as_data *ad, int data_dir)
  * existing request against the same sector), which can happen when using
  * direct IO, then return the alias.
  */
-static struct as_rq *as_add_arq_rb(struct as_data *ad, struct as_rq *arq)
+static struct as_rq *__as_add_arq_rb(struct as_data *ad, struct as_rq *arq)
 {
 	struct rb_node **p = &ARQ_RB_ROOT(ad, arq)->rb_node;
 	struct rb_node *parent = NULL;
@@ -397,6 +400,16 @@ static struct as_rq *as_add_arq_rb(struct as_data *ad, struct as_rq *arq)
 	return NULL;
 }
 
+static void as_add_arq_rb(struct as_data *ad, struct as_rq *arq)
+{
+	struct as_rq *alias;
+
+	while ((unlikely(alias = __as_add_arq_rb(ad, arq)))) {
+		as_move_to_dispatch(ad, alias);
+		as_antic_stop(ad);
+	}
+}
+
 static inline void as_del_arq_rb(struct as_data *ad, struct as_rq *arq)
 {
 	if (!ON_RB(&arq->rb_node)) {
@@ -1133,23 +1146,6 @@ static void as_move_to_dispatch(struct as_data *ad, struct as_rq *arq)
 	/*
 	 * take it off the sort and fifo list, add to dispatch queue
 	 */
-	while (!list_empty(&rq->queuelist)) {
-		struct request *__rq = list_entry_rq(rq->queuelist.next);
-		struct as_rq *__arq = RQ_DATA(__rq);
-
-		list_del(&__rq->queuelist);
-
-		elv_dispatch_add_tail(ad->q, __rq);
-
-		if (__arq->io_context && __arq->io_context->aic)
-			atomic_inc(&__arq->io_context->aic->nr_dispatched);
-
-		WARN_ON(__arq->state != AS_RQ_QUEUED);
-		__arq->state = AS_RQ_DISPATCHED;
-
-		ad->nr_dispatched++;
-	}
-
 	as_remove_queued_request(ad->q, rq);
 	WARN_ON(arq->state != AS_RQ_QUEUED);
 
@@ -1325,42 +1321,6 @@ static int as_dispatch_request(request_queue_t *q, int force)
 	return 1;
 }
 
-/*
- * Add arq to a list behind alias
- */
-static inline void
-as_add_aliased_request(struct as_data *ad, struct as_rq *arq,
-				struct as_rq *alias)
-{
-	struct request  *req = arq->request;
-	struct list_head *insert = alias->request->queuelist.prev;
-
-	/*
-	 * Transfer list of aliases
-	 */
-	while (!list_empty(&req->queuelist)) {
-		struct request *__rq = list_entry_rq(req->queuelist.next);
-		struct as_rq *__arq = RQ_DATA(__rq);
-
-		list_move_tail(&__rq->queuelist, &alias->request->queuelist);
-
-		WARN_ON(__arq->state != AS_RQ_QUEUED);
-	}
-
-	/*
-	 * Another request with the same start sector on the rbtree.
-	 * Link this request to that sector. They are untangled in
-	 * as_move_to_dispatch
-	 */
-	list_add(&arq->request->queuelist, insert);
-
-	/*
-	 * Don't want to have to handle merges.
-	 */
-	as_del_arq_hash(arq);
-	arq->request->flags |= REQ_NOMERGE;
-}
-
 /*
  * add arq to rbtree and fifo
  */
@@ -1368,7 +1328,6 @@ static void as_add_request(request_queue_t *q, struct request *rq)
 {
 	struct as_data *ad = q->elevator->elevator_data;
 	struct as_rq *arq = RQ_DATA(rq);
-	struct as_rq *alias;
 	int data_dir;
 
 	arq->state = AS_RQ_NEW;
@@ -1387,33 +1346,17 @@ static void as_add_request(request_queue_t *q, struct request *rq)
 		atomic_inc(&arq->io_context->aic->nr_queued);
 	}
 
-	alias = as_add_arq_rb(ad, arq);
-	if (!alias) {
-		/*
-		 * set expire time (only used for reads) and add to fifo list
-		 */
-		arq->expires = jiffies + ad->fifo_expire[data_dir];
-		list_add_tail(&arq->fifo, &ad->fifo_list[data_dir]);
+	as_add_arq_rb(ad, arq);
+	if (rq_mergeable(arq->request))
+		as_add_arq_hash(ad, arq);
 
-		if (rq_mergeable(arq->request))
-			as_add_arq_hash(ad, arq);
-		as_update_arq(ad, arq); /* keep state machine up to date */
-
-	} else {
-		as_add_aliased_request(ad, arq, alias);
-
-		/*
-		 * have we been anticipating this request?
-		 * or does it come from the same process as the one we are
-		 * anticipating for?
-		 */
-		if (ad->antic_status == ANTIC_WAIT_REQ
-				|| ad->antic_status == ANTIC_WAIT_NEXT) {
-			if (as_can_break_anticipation(ad, arq))
-				as_antic_stop(ad);
-		}
-	}
+	/*
+	 * set expire time (only used for reads) and add to fifo list
+	 */
+	arq->expires = jiffies + ad->fifo_expire[data_dir];
+	list_add_tail(&arq->fifo, &ad->fifo_list[data_dir]);
 
+	as_update_arq(ad, arq); /* keep state machine up to date */
 	arq->state = AS_RQ_QUEUED;
 }
 
@@ -1536,23 +1479,8 @@ static void as_merged_request(request_queue_t *q, struct request *req)
 	 * if the merge was a front merge, we need to reposition request
 	 */
 	if (rq_rb_key(req) != arq->rb_key) {
-		struct as_rq *alias, *next_arq = NULL;
-
-		if (ad->next_arq[arq->is_sync] == arq)
-			next_arq = as_find_next_arq(ad, arq);
-
-		/*
-		 * Note! We should really be moving any old aliased requests
-		 * off this request and try to insert them into the rbtree. We
-		 * currently don't bother. Ditto the next function.
-		 */
 		as_del_arq_rb(ad, arq);
-		if ((alias = as_add_arq_rb(ad, arq))) {
-			list_del_init(&arq->fifo);
-			as_add_aliased_request(ad, arq, alias);
-			if (next_arq)
-				ad->next_arq[arq->is_sync] = next_arq;
-		}
+		as_add_arq_rb(ad, arq);
 		/*
 		 * Note! At this stage of this and the next function, our next
 		 * request may not be optimal - eg the request may have "grown"
@@ -1579,18 +1507,8 @@ static void as_merged_requests(request_queue_t *q, struct request *req,
 	as_add_arq_hash(ad, arq);
 
 	if (rq_rb_key(req) != arq->rb_key) {
-		struct as_rq *alias, *next_arq = NULL;
-
-		if (ad->next_arq[arq->is_sync] == arq)
-			next_arq = as_find_next_arq(ad, arq);
-
 		as_del_arq_rb(ad, arq);
-		if ((alias = as_add_arq_rb(ad, arq))) {
-			list_del_init(&arq->fifo);
-			as_add_aliased_request(ad, arq, alias);
-			if (next_arq)
-				ad->next_arq[arq->is_sync] = next_arq;
-		}
+		as_add_arq_rb(ad, arq);
 	}
 
 	/*
@@ -1609,18 +1527,6 @@ static void as_merged_requests(request_queue_t *q, struct request *req,
 		}
 	}
 
-	/*
-	 * Transfer list of aliases
-	 */
-	while (!list_empty(&next->queuelist)) {
-		struct request *__rq = list_entry_rq(next->queuelist.next);
-		struct as_rq *__arq = RQ_DATA(__rq);
-
-		list_move_tail(&__rq->queuelist, &req->queuelist);
-
-		WARN_ON(__arq->state != AS_RQ_QUEUED);
-	}
-
 	/*
 	 * kill knowledge of next, this one is a goner
 	 */

block/cfq-iosched.c

@@ -25,15 +25,15 @@
 /*
  * tunables
  */
-static int cfq_quantum = 4;		/* max queue in one round of service */
-static int cfq_queued = 8;		/* minimum rq allocate limit per-queue*/
-static int cfq_fifo_expire[2] = { HZ / 4, HZ / 8 };
-static int cfq_back_max = 16 * 1024;	/* maximum backwards seek, in KiB */
-static int cfq_back_penalty = 2;	/* penalty of a backwards seek */
+static const int cfq_quantum = 4;		/* max queue in one round of service */
+static const int cfq_queued = 8;		/* minimum rq allocate limit per-queue*/
+static const int cfq_fifo_expire[2] = { HZ / 4, HZ / 8 };
+static const int cfq_back_max = 16 * 1024;	/* maximum backwards seek, in KiB */
+static const int cfq_back_penalty = 2;		/* penalty of a backwards seek */
 
-static int cfq_slice_sync = HZ / 10;
+static const int cfq_slice_sync = HZ / 10;
 static int cfq_slice_async = HZ / 25;
-static int cfq_slice_async_rq = 2;
+static const int cfq_slice_async_rq = 2;
 static int cfq_slice_idle = HZ / 100;
 
 #define CFQ_IDLE_GRACE		(HZ / 10)
@@ -45,7 +45,7 @@ static int cfq_slice_idle = HZ / 100;
 /*
  * disable queueing at the driver/hardware level
  */
-static int cfq_max_depth = 2;
+static const int cfq_max_depth = 2;
 
 /*
  * for the hash of cfqq inside the cfqd

block/deadline-iosched.c

@@ -19,10 +19,10 @@
 /*
  * See Documentation/block/deadline-iosched.txt
  */
-static int read_expire = HZ / 2;  /* max time before a read is submitted. */
-static int write_expire = 5 * HZ; /* ditto for writes, these limits are SOFT! */
-static int writes_starved = 2;    /* max times reads can starve a write */
-static int fifo_batch = 16;       /* # of sequential requests treated as one
+static const int read_expire = HZ / 2;  /* max time before a read is submitted. */
+static const int write_expire = 5 * HZ; /* ditto for writes, these limits are SOFT! */
+static const int writes_starved = 2;    /* max times reads can starve a write */
+static const int fifo_batch = 16;       /* # of sequential requests treated as one
 				     by the above parameters. For throughput. */
 
 static const int deadline_hash_shift = 5;

block/elevator.c

@@ -304,15 +304,7 @@ void elv_requeue_request(request_queue_t *q, struct request *rq)
 
 	rq->flags &= ~REQ_STARTED;
 
-	/*
-	 * if this is the flush, requeue the original instead and drop the flush
-	 */
-	if (rq->flags & REQ_BAR_FLUSH) {
-		clear_bit(QUEUE_FLAG_FLUSH, &q->queue_flags);
-		rq = rq->end_io_data;
-	}
-
-	__elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 0);
+	__elv_add_request(q, rq, ELEVATOR_INSERT_REQUEUE, 0);
 }
 
 static void elv_drain_elevator(request_queue_t *q)
@@ -332,7 +324,18 @@ static void elv_drain_elevator(request_queue_t *q)
 void __elv_add_request(request_queue_t *q, struct request *rq, int where,
 		       int plug)
 {
+	struct list_head *pos;
+	unsigned ordseq;
+
+	if (q->ordcolor)
+		rq->flags |= REQ_ORDERED_COLOR;
+
 	if (rq->flags & (REQ_SOFTBARRIER | REQ_HARDBARRIER)) {
+		/*
+		 * toggle ordered color
+		 */
+		q->ordcolor ^= 1;
+
 		/*
 		 * barriers implicitly indicate back insertion
 		 */
@@ -393,6 +396,30 @@ void __elv_add_request(request_queue_t *q, struct request *rq, int where,
 		q->elevator->ops->elevator_add_req_fn(q, rq);
 		break;
 
+	case ELEVATOR_INSERT_REQUEUE:
+		/*
+		 * If ordered flush isn't in progress, we do front
+		 * insertion; otherwise, requests should be requeued
+		 * in ordseq order.
+		 */
+		rq->flags |= REQ_SOFTBARRIER;
+
+		if (q->ordseq == 0) {
+			list_add(&rq->queuelist, &q->queue_head);
+			break;
+		}
+
+		ordseq = blk_ordered_req_seq(rq);
+
+		list_for_each(pos, &q->queue_head) {
+			struct request *pos_rq = list_entry_rq(pos);
+			if (ordseq <= blk_ordered_req_seq(pos_rq))
+				break;
+		}
+
+		list_add_tail(&rq->queuelist, pos);
+		break;
+
 	default:
 		printk(KERN_ERR "%s: bad insertion point %d\n",
 		       __FUNCTION__, where);
@@ -422,25 +449,16 @@ static inline struct request *__elv_next_request(request_queue_t *q)
 {
 	struct request *rq;
 
-	if (unlikely(list_empty(&q->queue_head) &&
-		     !q->elevator->ops->elevator_dispatch_fn(q, 0)))
-		return NULL;
-
-	rq = list_entry_rq(q->queue_head.next);
-
-	/*
-	 * if this is a barrier write and the device has to issue a
-	 * flush sequence to support it, check how far we are
-	 */
-	if (blk_fs_request(rq) && blk_barrier_rq(rq)) {
-		BUG_ON(q->ordered == QUEUE_ORDERED_NONE);
+	while (1) {
+		while (!list_empty(&q->queue_head)) {
+			rq = list_entry_rq(q->queue_head.next);
+			if (blk_do_ordered(q, &rq))
+				return rq;
+		}
 
-		if (q->ordered == QUEUE_ORDERED_FLUSH &&
-		    !blk_barrier_preflush(rq))
-			rq = blk_start_pre_flush(q, rq);
+		if (!q->elevator->ops->elevator_dispatch_fn(q, 0))
+			return NULL;
 	}
-
-	return rq;
 }
 
 struct request *elv_next_request(request_queue_t *q)
@@ -498,7 +516,7 @@ struct request *elv_next_request(request_queue_t *q)
 			blkdev_dequeue_request(rq);
 			rq->flags |= REQ_QUIET;
 			end_that_request_chunk(rq, 0, nr_bytes);
-			end_that_request_last(rq);
+			end_that_request_last(rq, 0);
 		} else {
 			printk(KERN_ERR "%s: bad return=%d\n", __FUNCTION__,
 								ret);
@@ -593,7 +611,21 @@ void elv_completed_request(request_queue_t *q, struct request *rq)
 	 * request is released from the driver, io must be done
 	 */
 	if (blk_account_rq(rq)) {
+		struct request *first_rq = list_entry_rq(q->queue_head.next);
+
 		q->in_flight--;
+
+		/*
+		 * Check if the queue is waiting for fs requests to be
+		 * drained for flush sequence.
+		 */
+		if (q->ordseq && q->in_flight == 0 &&
+		    blk_ordered_cur_seq(q) == QUEUE_ORDSEQ_DRAIN &&
+		    blk_ordered_req_seq(first_rq) > QUEUE_ORDSEQ_DRAIN) {
+			blk_ordered_complete_seq(q, QUEUE_ORDSEQ_DRAIN, 0);
+			q->request_fn(q);
+		}
+
 		if (blk_sorted_rq(rq) && e->ops->elevator_completed_req_fn)
 			e->ops->elevator_completed_req_fn(q, rq);
 	}

block/scsi_ioctl.c

@@ -46,7 +46,7 @@ EXPORT_SYMBOL(scsi_command_size);
 
 static int sg_get_version(int __user *p)
 {
-	static int sg_version_num = 30527;
+	static const int sg_version_num = 30527;
 	return put_user(sg_version_num, p);
 }
 

drivers/block/DAC960.c

@@ -3471,7 +3471,7 @@ static inline boolean DAC960_ProcessCompletedRequest(DAC960_Command_T *Command,
 
 	 if (!end_that_request_first(Request, UpToDate, Command->BlockCount)) {
 
- 	 	end_that_request_last(Request);
+ 	 	end_that_request_last(Request, UpToDate);
 
 		if (Command->Completion) {
 			complete(Command->Completion);

drivers/block/cciss.c

@@ -2310,7 +2310,7 @@ static inline void complete_command( ctlr_info_t *h, CommandList_struct *cmd,
 	printk("Done with %p\n", cmd->rq);
 #endif /* CCISS_DEBUG */ 
 
-	end_that_request_last(cmd->rq);
+	end_that_request_last(cmd->rq, status ? 1 : -EIO);
 	cmd_free(h,cmd,1);
 }
 

drivers/block/cpqarray.c

@@ -1036,7 +1036,7 @@ static inline void complete_command(cmdlist_t *cmd, int timeout)
 	complete_buffers(cmd->rq->bio, ok);
 
         DBGPX(printk("Done with %p\n", cmd->rq););
-	end_that_request_last(cmd->rq);
+	end_that_request_last(cmd->rq, ok ? 1 : -EIO);
 }
 
 /*

drivers/block/floppy.c

@@ -2301,7 +2301,7 @@ static void floppy_end_request(struct request *req, int uptodate)
 	add_disk_randomness(req->rq_disk);
 	floppy_off((long)req->rq_disk->private_data);
 	blkdev_dequeue_request(req);
-	end_that_request_last(req);
+	end_that_request_last(req, uptodate);
 
 	/* We're done with the request */
 	current_req = NULL;

drivers/block/nbd.c

@@ -140,7 +140,7 @@ static void nbd_end_request(struct request *req)
 
 	spin_lock_irqsave(q->queue_lock, flags);
 	if (!end_that_request_first(req, uptodate, req->nr_sectors)) {
-		end_that_request_last(req);
+		end_that_request_last(req, uptodate);
 	}
 	spin_unlock_irqrestore(q->queue_lock, flags);
 }

drivers/block/sx8.c

@@ -770,7 +770,7 @@ static inline void carm_end_request_queued(struct carm_host *host,
 	rc = end_that_request_first(req, uptodate, req->hard_nr_sectors);
 	assert(rc == 0);
 
-	end_that_request_last(req);
+	end_that_request_last(req, uptodate);
 
 	rc = carm_put_request(host, crq);
 	assert(rc == 0);

drivers/block/ub.c

@@ -951,7 +951,7 @@ static void ub_rw_cmd_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
 static void ub_end_rq(struct request *rq, int uptodate)
 {
 	end_that_request_first(rq, uptodate, rq->hard_nr_sectors);
-	end_that_request_last(rq);
+	end_that_request_last(rq, uptodate);
 }
 
 static int ub_rw_cmd_retry(struct ub_dev *sc, struct ub_lun *lun,

drivers/block/viodasd.c

@@ -305,7 +305,7 @@ static void viodasd_end_request(struct request *req, int uptodate,
 	if (end_that_request_first(req, uptodate, num_sectors))
 		return;
 	add_disk_randomness(req->rq_disk);
-	end_that_request_last(req);
+	end_that_request_last(req, uptodate);
 }
 
 /*

drivers/cdrom/cdu31a.c

@@ -1402,7 +1402,7 @@ static void do_cdu31a_request(request_queue_t * q)
 			if (!end_that_request_first(req, 1, nblock)) {
 				spin_lock_irq(q->queue_lock);
 				blkdev_dequeue_request(req);
-				end_that_request_last(req);
+				end_that_request_last(req, 1);
 				spin_unlock_irq(q->queue_lock);
 			}
 			continue;

drivers/ide/ide-cd.c

@@ -614,7 +614,7 @@ static void cdrom_end_request (ide_drive_t *drive, int uptodate)
 			 */
 			spin_lock_irqsave(&ide_lock, flags);
 			end_that_request_chunk(failed, 0, failed->data_len);
-			end_that_request_last(failed);
+			end_that_request_last(failed, 0);
 			spin_unlock_irqrestore(&ide_lock, flags);
 		}
 
@@ -1735,7 +1735,7 @@ static ide_startstop_t cdrom_newpc_intr(ide_drive_t *drive)
 
 	spin_lock_irqsave(&ide_lock, flags);
 	blkdev_dequeue_request(rq);
-	end_that_request_last(rq);
+	end_that_request_last(rq, 1);
 	HWGROUP(drive)->rq = NULL;
 	spin_unlock_irqrestore(&ide_lock, flags);
 	return ide_stopped;

drivers/ide/ide-disk.c

@@ -681,50 +681,9 @@ static ide_proc_entry_t idedisk_proc[] = {
 
 #endif	/* CONFIG_PROC_FS */
 
-static void idedisk_end_flush(request_queue_t *q, struct request *flush_rq)
+static void idedisk_prepare_flush(request_queue_t *q, struct request *rq)
 {
 	ide_drive_t *drive = q->queuedata;
-	struct request *rq = flush_rq->end_io_data;
-	int good_sectors = rq->hard_nr_sectors;
-	int bad_sectors;
-	sector_t sector;
-
-	if (flush_rq->errors & ABRT_ERR) {
-		printk(KERN_ERR "%s: barrier support doesn't work\n", drive->name);
-		blk_queue_ordered(drive->queue, QUEUE_ORDERED_NONE);
-		blk_queue_issue_flush_fn(drive->queue, NULL);
-		good_sectors = 0;
-	} else if (flush_rq->errors) {
-		good_sectors = 0;
-		if (blk_barrier_preflush(rq)) {
-			sector = ide_get_error_location(drive,flush_rq->buffer);
-			if ((sector >= rq->hard_sector) &&
-			    (sector < rq->hard_sector + rq->hard_nr_sectors))
-				good_sectors = sector - rq->hard_sector;
-		}
-	}
-
-	if (flush_rq->errors)
-		printk(KERN_ERR "%s: failed barrier write: "
-				"sector=%Lx(good=%d/bad=%d)\n",
-				drive->name, (unsigned long long)rq->sector,
-				good_sectors,
-				(int) (rq->hard_nr_sectors-good_sectors));
-
-	bad_sectors = rq->hard_nr_sectors - good_sectors;
-
-	if (good_sectors)
-		__ide_end_request(drive, rq, 1, good_sectors);
-	if (bad_sectors)
-		__ide_end_request(drive, rq, 0, bad_sectors);
-}
-
-static int idedisk_prepare_flush(request_queue_t *q, struct request *rq)
-{
-	ide_drive_t *drive = q->queuedata;
-
-	if (!drive->wcache)
-		return 0;
 
 	memset(rq->cmd, 0, sizeof(rq->cmd));
 
@@ -735,9 +694,8 @@ static int idedisk_prepare_flush(request_queue_t *q, struct request *rq)
 		rq->cmd[0] = WIN_FLUSH_CACHE;
 
 
-	rq->flags |= REQ_DRIVE_TASK | REQ_SOFTBARRIER;
+	rq->flags |= REQ_DRIVE_TASK;
 	rq->buffer = rq->cmd;
-	return 1;
 }
 
 static int idedisk_issue_flush(request_queue_t *q, struct gendisk *disk,
@@ -794,27 +752,64 @@ static int set_nowerr(ide_drive_t *drive, int arg)
 	return 0;
 }
 
+static void update_ordered(ide_drive_t *drive)
+{
+	struct hd_driveid *id = drive->id;
+	unsigned ordered = QUEUE_ORDERED_NONE;
+	prepare_flush_fn *prep_fn = NULL;
+	issue_flush_fn *issue_fn = NULL;
+
+	if (drive->wcache) {
+		unsigned long long capacity;
+		int barrier;
+		/*
+		 * We must avoid issuing commands a drive does not
+		 * understand or we may crash it. We check flush cache
+		 * is supported. We also check we have the LBA48 flush
+		 * cache if the drive capacity is too large. By this
+		 * time we have trimmed the drive capacity if LBA48 is
+		 * not available so we don't need to recheck that.
+		 */
+		capacity = idedisk_capacity(drive);
+		barrier = ide_id_has_flush_cache(id) &&
+			(drive->addressing == 0 || capacity <= (1ULL << 28) ||
+			 ide_id_has_flush_cache_ext(id));
+
+		printk(KERN_INFO "%s: cache flushes %ssupported\n",
+		       drive->name, barrier ? "" : "not");
+
+		if (barrier) {
+			ordered = QUEUE_ORDERED_DRAIN_FLUSH;
+			prep_fn = idedisk_prepare_flush;
+			issue_fn = idedisk_issue_flush;
+		}
+	} else
+		ordered = QUEUE_ORDERED_DRAIN;
+
+	blk_queue_ordered(drive->queue, ordered, prep_fn);
+	blk_queue_issue_flush_fn(drive->queue, issue_fn);
+}
+
 static int write_cache(ide_drive_t *drive, int arg)
 {
 	ide_task_t args;
-	int err;
-
-	if (!ide_id_has_flush_cache(drive->id))
-		return 1;
+	int err = 1;
 
-	memset(&args, 0, sizeof(ide_task_t));
-	args.tfRegister[IDE_FEATURE_OFFSET]	= (arg) ?
+	if (ide_id_has_flush_cache(drive->id)) {
+		memset(&args, 0, sizeof(ide_task_t));
+		args.tfRegister[IDE_FEATURE_OFFSET]	= (arg) ?
 			SETFEATURES_EN_WCACHE : SETFEATURES_DIS_WCACHE;
-	args.tfRegister[IDE_COMMAND_OFFSET]	= WIN_SETFEATURES;
-	args.command_type			= IDE_DRIVE_TASK_NO_DATA;
-	args.handler				= &task_no_data_intr;
+		args.tfRegister[IDE_COMMAND_OFFSET]	= WIN_SETFEATURES;
+		args.command_type		= IDE_DRIVE_TASK_NO_DATA;
+		args.handler			= &task_no_data_intr;
+		err = ide_raw_taskfile(drive, &args, NULL);
+		if (err == 0)
+			drive->wcache = arg;
+	}
 
-	err = ide_raw_taskfile(drive, &args, NULL);
-	if (err)
-		return err;
+	update_ordered(drive);
 
-	drive->wcache = arg;
-	return 0;
+	return err;
 }
 
 static int do_idedisk_flushcache (ide_drive_t *drive)
@@ -888,7 +883,6 @@ static void idedisk_setup (ide_drive_t *drive)
 {
 	struct hd_driveid *id = drive->id;
 	unsigned long long capacity;
-	int barrier;
 
 	idedisk_add_settings(drive);
 
@@ -992,31 +986,6 @@ static void idedisk_setup (ide_drive_t *drive)
 		drive->wcache = 1;
 
 	write_cache(drive, 1);
-
-	/*
-	 * We must avoid issuing commands a drive does not understand
-	 * or we may crash it. We check flush cache is supported. We also
-	 * check we have the LBA48 flush cache if the drive capacity is
-	 * too large. By this time we have trimmed the drive capacity if
-	 * LBA48 is not available so we don't need to recheck that.
-	 */
-	barrier = 0;
-	if (ide_id_has_flush_cache(id))
-		barrier = 1;
-	if (drive->addressing == 1) {
-		/* Can't issue the correct flush ? */
-		if (capacity > (1ULL << 28) && !ide_id_has_flush_cache_ext(id))
-			barrier = 0;
-	}
-
-	printk(KERN_INFO "%s: cache flushes %ssupported\n",
-		drive->name, barrier ? "" : "not ");
-	if (barrier) {
-		blk_queue_ordered(drive->queue, QUEUE_ORDERED_FLUSH);
-		drive->queue->prepare_flush_fn = idedisk_prepare_flush;
-		drive->queue->end_flush_fn = idedisk_end_flush;
-		blk_queue_issue_flush_fn(drive->queue, idedisk_issue_flush);
-	}
 }
 
 static void ide_cacheflush_p(ide_drive_t *drive)

drivers/ide/ide-io.c

@@ -89,7 +89,7 @@ int __ide_end_request(ide_drive_t *drive, struct request *rq, int uptodate,
 
 		blkdev_dequeue_request(rq);
 		HWGROUP(drive)->rq = NULL;
-		end_that_request_last(rq);
+		end_that_request_last(rq, uptodate);
 		ret = 0;
 	}
 	return ret;
@@ -119,10 +119,7 @@ int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors)
 	if (!nr_sectors)
 		nr_sectors = rq->hard_cur_sectors;
 
-	if (blk_complete_barrier_rq_locked(drive->queue, rq, nr_sectors))
-		ret = rq->nr_sectors != 0;
-	else
-		ret = __ide_end_request(drive, rq, uptodate, nr_sectors);
+	ret = __ide_end_request(drive, rq, uptodate, nr_sectors);
 
 	spin_unlock_irqrestore(&ide_lock, flags);
 	return ret;
@@ -247,7 +244,7 @@ static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq)
 	}
 	blkdev_dequeue_request(rq);
 	HWGROUP(drive)->rq = NULL;
-	end_that_request_last(rq);
+	end_that_request_last(rq, 1);
 	spin_unlock_irqrestore(&ide_lock, flags);
 }
 
@@ -379,7 +376,7 @@ void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err)
 	blkdev_dequeue_request(rq);
 	HWGROUP(drive)->rq = NULL;
 	rq->errors = err;
-	end_that_request_last(rq);
+	end_that_request_last(rq, !rq->errors);
 	spin_unlock_irqrestore(&ide_lock, flags);
 }
 

drivers/message/i2o/i2o_block.c

@@ -468,7 +468,7 @@ static void i2o_block_end_request(struct request *req, int uptodate,
 
 	spin_lock_irqsave(q->queue_lock, flags);
 
-	end_that_request_last(req);
+	end_that_request_last(req, uptodate);
 
 	if (likely(dev)) {
 		dev->open_queue_depth--;

drivers/mmc/mmc_block.c

@@ -263,7 +263,7 @@ static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
 			 */
 			add_disk_randomness(req->rq_disk);
 			blkdev_dequeue_request(req);
-			end_that_request_last(req);
+			end_that_request_last(req, 1);
 		}
 		spin_unlock_irq(&md->lock);
 	} while (ret);
@@ -289,7 +289,7 @@ static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
 
 	add_disk_randomness(req->rq_disk);
 	blkdev_dequeue_request(req);
-	end_that_request_last(req);
+	end_that_request_last(req, 0);
 	spin_unlock_irq(&md->lock);
 
 	return 0;

drivers/s390/block/dasd.c

@@ -1035,7 +1035,7 @@ dasd_end_request(struct request *req, int uptodate)
 	if (end_that_request_first(req, uptodate, req->hard_nr_sectors))
 		BUG();
 	add_disk_randomness(req->rq_disk);
-	end_that_request_last(req);
+	end_that_request_last(req, uptodate);
 }
 
 /*

drivers/s390/char/tape_block.c

@@ -78,7 +78,7 @@ tapeblock_end_request(struct request *req, int uptodate)
 {
 	if (end_that_request_first(req, uptodate, req->hard_nr_sectors))
 		BUG();
-	end_that_request_last(req);
+	end_that_request_last(req, uptodate);
 }
 
 static void

drivers/scsi/ahci.c

@@ -214,7 +214,6 @@ static struct scsi_host_template ahci_sht = {
 	.dma_boundary		= AHCI_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
 	.bios_param		= ata_std_bios_param,
-	.ordered_flush		= 1,
 };
 
 static const struct ata_port_operations ahci_ops = {

drivers/scsi/ata_piix.c

@@ -187,7 +187,6 @@ static struct scsi_host_template piix_sht = {
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
 	.bios_param		= ata_std_bios_param,
-	.ordered_flush		= 1,
 	.resume			= ata_scsi_device_resume,
 	.suspend		= ata_scsi_device_suspend,
 };

drivers/scsi/hosts.c

@@ -347,17 +347,8 @@ struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize)
 	shost->cmd_per_lun = sht->cmd_per_lun;
 	shost->unchecked_isa_dma = sht->unchecked_isa_dma;
 	shost->use_clustering = sht->use_clustering;
-	shost->ordered_flush = sht->ordered_flush;
 	shost->ordered_tag = sht->ordered_tag;
 
-	/*
-	 * hosts/devices that do queueing must support ordered tags
-	 */
-	if (shost->can_queue > 1 && shost->ordered_flush) {
-		printk(KERN_ERR "scsi: ordered flushes don't support queueing\n");
-		shost->ordered_flush = 0;
-	}
-
 	if (sht->max_host_blocked)
 		shost->max_host_blocked = sht->max_host_blocked;
 	else

drivers/scsi/ide-scsi.c

@@ -1046,7 +1046,7 @@ static int idescsi_eh_reset (struct scsi_cmnd *cmd)
 
 	/* kill current request */
 	blkdev_dequeue_request(req);
-	end_that_request_last(req);
+	end_that_request_last(req, 0);
 	if (req->flags & REQ_SENSE)
 		kfree(scsi->pc->buffer);
 	kfree(scsi->pc);
@@ -1056,7 +1056,7 @@ static int idescsi_eh_reset (struct scsi_cmnd *cmd)
 	/* now nuke the drive queue */
 	while ((req = elv_next_request(drive->queue))) {
 		blkdev_dequeue_request(req);
-		end_that_request_last(req);
+		end_that_request_last(req, 0);
 	}
 
 	HWGROUP(drive)->rq = NULL;

drivers/scsi/libata-core.c

@@ -562,16 +562,28 @@ static const u8 ata_rw_cmds[] = {
 	ATA_CMD_WRITE_MULTI,
 	ATA_CMD_READ_MULTI_EXT,
 	ATA_CMD_WRITE_MULTI_EXT,
+	0,
+	0,
+	0,
+	ATA_CMD_WRITE_MULTI_FUA_EXT,
 	/* pio */
 	ATA_CMD_PIO_READ,
 	ATA_CMD_PIO_WRITE,
 	ATA_CMD_PIO_READ_EXT,
 	ATA_CMD_PIO_WRITE_EXT,
+	0,
+	0,
+	0,
+	0,
 	/* dma */
 	ATA_CMD_READ,
 	ATA_CMD_WRITE,
 	ATA_CMD_READ_EXT,
-	ATA_CMD_WRITE_EXT
+	ATA_CMD_WRITE_EXT,
+	0,
+	0,
+	0,
+	ATA_CMD_WRITE_FUA_EXT
 };
 
 /**
@@ -584,25 +596,32 @@ static const u8 ata_rw_cmds[] = {
  *	LOCKING:
  *	caller.
  */
-void ata_rwcmd_protocol(struct ata_queued_cmd *qc)
+int ata_rwcmd_protocol(struct ata_queued_cmd *qc)
 {
 	struct ata_taskfile *tf = &qc->tf;
 	struct ata_device *dev = qc->dev;
+	u8 cmd;
 
-	int index, lba48, write;
+	int index, fua, lba48, write;
  
+	fua = (tf->flags & ATA_TFLAG_FUA) ? 4 : 0;
 	lba48 = (tf->flags & ATA_TFLAG_LBA48) ? 2 : 0;
 	write = (tf->flags & ATA_TFLAG_WRITE) ? 1 : 0;
 
 	if (dev->flags & ATA_DFLAG_PIO) {
 		tf->protocol = ATA_PROT_PIO;
-		index = dev->multi_count ? 0 : 4;
+		index = dev->multi_count ? 0 : 8;
 	} else {
 		tf->protocol = ATA_PROT_DMA;
-		index = 8;
+		index = 16;
 	}
 
-	tf->command = ata_rw_cmds[index + lba48 + write];
+	cmd = ata_rw_cmds[index + fua + lba48 + write];
+	if (cmd) {
+		tf->command = cmd;
+		return 0;
+	}
+	return -1;
 }
 
 static const char * const xfer_mode_str[] = {

drivers/scsi/libata-scsi.c

@@ -1096,11 +1096,13 @@ static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc, const u8 *scsicm
 	    scsicmd[0] == WRITE_16)
 		tf->flags |= ATA_TFLAG_WRITE;
 
-	/* Calculate the SCSI LBA and transfer length. */
+	/* Calculate the SCSI LBA, transfer length and FUA. */
 	switch (scsicmd[0]) {
 	case READ_10:
 	case WRITE_10:
 		scsi_10_lba_len(scsicmd, &block, &n_block);
+		if (unlikely(scsicmd[1] & (1 << 3)))
+			tf->flags |= ATA_TFLAG_FUA;
 		break;
 	case READ_6:
 	case WRITE_6:
@@ -1115,6 +1117,8 @@ static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc, const u8 *scsicm
 	case READ_16:
 	case WRITE_16:
 		scsi_16_lba_len(scsicmd, &block, &n_block);
+		if (unlikely(scsicmd[1] & (1 << 3)))
+			tf->flags |= ATA_TFLAG_FUA;
 		break;
 	default:
 		DPRINTK("no-byte command\n");
@@ -1158,7 +1162,8 @@ static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc, const u8 *scsicm
 			tf->device |= (block >> 24) & 0xf;
 		}
 
-		ata_rwcmd_protocol(qc);
+		if (unlikely(ata_rwcmd_protocol(qc) < 0))
+			goto invalid_fld;
 
 		qc->nsect = n_block;
 		tf->nsect = n_block & 0xff;
@@ -1176,7 +1181,8 @@ static unsigned int ata_scsi_rw_xlat(struct ata_queued_cmd *qc, const u8 *scsicm
 		if ((block >> 28) || (n_block > 256))
 			goto out_of_range;
 
-		ata_rwcmd_protocol(qc);
+		if (unlikely(ata_rwcmd_protocol(qc) < 0))
+			goto invalid_fld;
 
 		/* Convert LBA to CHS */
 		track = (u32)block / dev->sectors;
@@ -1711,6 +1717,7 @@ static unsigned int ata_msense_rw_recovery(u8 **ptr_io, const u8 *last)
 unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf,
 				  unsigned int buflen)
 {
+	struct ata_device *dev = args->dev;
 	u8 *scsicmd = args->cmd->cmnd, *p, *last;
 	const u8 sat_blk_desc[] = {
 		0, 0, 0, 0,	/* number of blocks: sat unspecified */
@@ -1719,6 +1726,7 @@ unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf,
 	};
 	u8 pg, spg;
 	unsigned int ebd, page_control, six_byte, output_len, alloc_len, minlen;
+	u8 dpofua;
 
 	VPRINTK("ENTER\n");
 
@@ -1787,9 +1795,17 @@ unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf,
 
 	if (minlen < 1)
 		return 0;
+
+	dpofua = 0;
+	if (ata_id_has_fua(args->id) && dev->flags & ATA_DFLAG_LBA48 &&
+	    (!(dev->flags & ATA_DFLAG_PIO) || dev->multi_count))
+		dpofua = 1 << 4;
+
 	if (six_byte) {
 		output_len--;
 		rbuf[0] = output_len;
+		if (minlen > 2)
+			rbuf[2] |= dpofua;
 		if (ebd) {
 			if (minlen > 3)
 				rbuf[3] = sizeof(sat_blk_desc);
@@ -1802,6 +1818,8 @@ unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf,
 		rbuf[0] = output_len >> 8;
 		if (minlen > 1)
 			rbuf[1] = output_len;
+		if (minlen > 3)
+			rbuf[3] |= dpofua;
 		if (ebd) {
 			if (minlen > 7)
 				rbuf[7] = sizeof(sat_blk_desc);
@@ -2462,7 +2480,7 @@ int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
 		if (xlat_func)
 			ata_scsi_translate(ap, dev, cmd, done, xlat_func);
 		else
-			ata_scsi_simulate(dev->id, cmd, done);
+			ata_scsi_simulate(ap, dev, cmd, done);
 	} else
 		ata_scsi_translate(ap, dev, cmd, done, atapi_xlat);
 
@@ -2485,14 +2503,16 @@ int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
  *	spin_lock_irqsave(host_set lock)
  */
 
-void ata_scsi_simulate(u16 *id,
+void ata_scsi_simulate(struct ata_port *ap, struct ata_device *dev,
 		      struct scsi_cmnd *cmd,
 		      void (*done)(struct scsi_cmnd *))
 {
 	struct ata_scsi_args args;
 	const u8 *scsicmd = cmd->cmnd;
 
-	args.id = id;
+	args.ap = ap;
+	args.dev = dev;
+	args.id = dev->id;
 	args.cmd = cmd;
 	args.done = done;
 

drivers/scsi/libata.h

@@ -32,6 +32,8 @@
 #define DRV_VERSION	"1.20"	/* must be exactly four chars */
 
 struct ata_scsi_args {
+	struct ata_port		*ap;
+	struct ata_device	*dev;
 	u16			*id;
 	struct scsi_cmnd	*cmd;
 	void			(*done)(struct scsi_cmnd *);
@@ -41,7 +43,7 @@ struct ata_scsi_args {
 extern int atapi_enabled;
 extern struct ata_queued_cmd *ata_qc_new_init(struct ata_port *ap,
 				      struct ata_device *dev);
-extern void ata_rwcmd_protocol(struct ata_queued_cmd *qc);
+extern int ata_rwcmd_protocol(struct ata_queued_cmd *qc);
 extern void ata_qc_free(struct ata_queued_cmd *qc);
 extern int ata_qc_issue(struct ata_queued_cmd *qc);
 extern int ata_check_atapi_dma(struct ata_queued_cmd *qc);

drivers/scsi/sata_mv.c

@@ -374,7 +374,6 @@ static struct scsi_host_template mv_sht = {
 	.dma_boundary		= MV_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
 	.bios_param		= ata_std_bios_param,
-	.ordered_flush		= 1,
 };
 
 static const struct ata_port_operations mv5_ops = {

drivers/scsi/sata_nv.c

@@ -235,7 +235,6 @@ static struct scsi_host_template nv_sht = {
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
 	.bios_param		= ata_std_bios_param,
-	.ordered_flush		= 1,
 };
 
 static const struct ata_port_operations nv_ops = {

drivers/scsi/sata_promise.c

@@ -114,7 +114,6 @@ static struct scsi_host_template pdc_ata_sht = {
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
 	.bios_param		= ata_std_bios_param,
-	.ordered_flush		= 1,
 };
 
 static const struct ata_port_operations pdc_sata_ops = {

drivers/scsi/sata_sil.c

@@ -147,7 +147,6 @@ static struct scsi_host_template sil_sht = {
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
 	.bios_param		= ata_std_bios_param,
-	.ordered_flush		= 1,
 };
 
 static const struct ata_port_operations sil_ops = {

drivers/scsi/sata_sil24.c

@@ -292,7 +292,6 @@ static struct scsi_host_template sil24_sht = {
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
 	.bios_param		= ata_std_bios_param,
-	.ordered_flush		= 1, /* NCQ not supported yet */
 };
 
 static const struct ata_port_operations sil24_ops = {

drivers/scsi/sata_sis.c

@@ -99,7 +99,6 @@ static struct scsi_host_template sis_sht = {
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
 	.bios_param		= ata_std_bios_param,
-	.ordered_flush		= 1,
 };
 
 static const struct ata_port_operations sis_ops = {

drivers/scsi/sata_svw.c

@@ -303,7 +303,6 @@ static struct scsi_host_template k2_sata_sht = {
 	.proc_info		= k2_sata_proc_info,
 #endif
 	.bios_param		= ata_std_bios_param,
-	.ordered_flush		= 1,
 };
 
 

drivers/scsi/sata_sx4.c

@@ -194,7 +194,6 @@ static struct scsi_host_template pdc_sata_sht = {
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
 	.bios_param		= ata_std_bios_param,
-	.ordered_flush		= 1,
 };
 
 static const struct ata_port_operations pdc_20621_ops = {

drivers/scsi/sata_uli.c

@@ -87,7 +87,6 @@ static struct scsi_host_template uli_sht = {
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
 	.bios_param		= ata_std_bios_param,
-	.ordered_flush		= 1,
 };
 
 static const struct ata_port_operations uli_ops = {

drivers/scsi/sata_via.c

@@ -106,7 +106,6 @@ static struct scsi_host_template svia_sht = {
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
 	.bios_param		= ata_std_bios_param,
-	.ordered_flush		= 1,
 };
 
 static const struct ata_port_operations svia_sata_ops = {

drivers/scsi/sata_vsc.c

@@ -235,7 +235,6 @@ static struct scsi_host_template vsc_sata_sht = {
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
 	.bios_param		= ata_std_bios_param,
-	.ordered_flush		= 1,
 };
 
 

drivers/scsi/scsi_lib.c

@@ -308,7 +308,7 @@ struct scsi_io_context {
 
 static kmem_cache_t *scsi_io_context_cache;
 
-static void scsi_end_async(struct request *req)
+static void scsi_end_async(struct request *req, int uptodate)
 {
 	struct scsi_io_context *sioc = req->end_io_data;
 
@@ -791,7 +791,7 @@ static struct scsi_cmnd *scsi_end_request(struct scsi_cmnd *cmd, int uptodate,
 	spin_lock_irqsave(q->queue_lock, flags);
 	if (blk_rq_tagged(req))
 		blk_queue_end_tag(q, req);
-	end_that_request_last(req);
+	end_that_request_last(req, uptodate);
 	spin_unlock_irqrestore(q->queue_lock, flags);
 
 	/*
@@ -932,9 +932,6 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes,
 	int sense_valid = 0;
 	int sense_deferred = 0;
 
-	if (blk_complete_barrier_rq(q, req, good_bytes >> 9))
-		return;
-
 	/*
 	 * Free up any indirection buffers we allocated for DMA purposes. 
 	 * For the case of a READ, we need to copy the data out of the
@@ -1199,38 +1196,6 @@ static int scsi_init_io(struct scsi_cmnd *cmd)
 	return BLKPREP_KILL;
 }
 
-static int scsi_prepare_flush_fn(request_queue_t *q, struct request *rq)
-{
-	struct scsi_device *sdev = q->queuedata;
-	struct scsi_driver *drv;
-
-	if (sdev->sdev_state == SDEV_RUNNING) {
-		drv = *(struct scsi_driver **) rq->rq_disk->private_data;
-
-		if (drv->prepare_flush)
-			return drv->prepare_flush(q, rq);
-	}
-
-	return 0;
-}
-
-static void scsi_end_flush_fn(request_queue_t *q, struct request *rq)
-{
-	struct scsi_device *sdev = q->queuedata;
-	struct request *flush_rq = rq->end_io_data;
-	struct scsi_driver *drv;
-
-	if (flush_rq->errors) {
-		printk("scsi: barrier error, disabling flush support\n");
-		blk_queue_ordered(q, QUEUE_ORDERED_NONE);
-	}
-
-	if (sdev->sdev_state == SDEV_RUNNING) {
-		drv = *(struct scsi_driver **) rq->rq_disk->private_data;
-		drv->end_flush(q, rq);
-	}
-}
-
 static int scsi_issue_flush_fn(request_queue_t *q, struct gendisk *disk,
 			       sector_t *error_sector)
 {
@@ -1703,17 +1668,6 @@ struct request_queue *scsi_alloc_queue(struct scsi_device *sdev)
 	blk_queue_segment_boundary(q, shost->dma_boundary);
 	blk_queue_issue_flush_fn(q, scsi_issue_flush_fn);
 
-	/*
-	 * ordered tags are superior to flush ordering
-	 */
-	if (shost->ordered_tag)
-		blk_queue_ordered(q, QUEUE_ORDERED_TAG);
-	else if (shost->ordered_flush) {
-		blk_queue_ordered(q, QUEUE_ORDERED_FLUSH);
-		q->prepare_flush_fn = scsi_prepare_flush_fn;
-		q->end_flush_fn = scsi_end_flush_fn;
-	}
-
 	if (!shost->use_clustering)
 		clear_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags);
 	return q;

drivers/scsi/sd.c

@@ -102,6 +102,7 @@ struct scsi_disk {
 	u8		write_prot;
 	unsigned	WCE : 1;	/* state of disk WCE bit */
 	unsigned	RCD : 1;	/* state of disk RCD bit, unused */
+	unsigned	DPOFUA : 1;	/* state of disk DPOFUA bit */
 };
 
 static DEFINE_IDR(sd_index_idr);
@@ -121,8 +122,7 @@ static void sd_shutdown(struct device *dev);
 static void sd_rescan(struct device *);
 static int sd_init_command(struct scsi_cmnd *);
 static int sd_issue_flush(struct device *, sector_t *);
-static void sd_end_flush(request_queue_t *, struct request *);
-static int sd_prepare_flush(request_queue_t *, struct request *);
+static void sd_prepare_flush(request_queue_t *, struct request *);
 static void sd_read_capacity(struct scsi_disk *sdkp, char *diskname,
 			     unsigned char *buffer);
 
@@ -137,8 +137,6 @@ static struct scsi_driver sd_template = {
 	.rescan			= sd_rescan,
 	.init_command		= sd_init_command,
 	.issue_flush		= sd_issue_flush,
-	.prepare_flush		= sd_prepare_flush,
-	.end_flush		= sd_end_flush,
 };
 
 /*
@@ -346,6 +344,7 @@ static int sd_init_command(struct scsi_cmnd * SCpnt)
 	
 	if (block > 0xffffffff) {
 		SCpnt->cmnd[0] += READ_16 - READ_6;
+		SCpnt->cmnd[1] |= blk_fua_rq(rq) ? 0x8 : 0;
 		SCpnt->cmnd[2] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
 		SCpnt->cmnd[3] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
 		SCpnt->cmnd[4] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
@@ -365,6 +364,7 @@ static int sd_init_command(struct scsi_cmnd * SCpnt)
 			this_count = 0xffff;
 
 		SCpnt->cmnd[0] += READ_10 - READ_6;
+		SCpnt->cmnd[1] |= blk_fua_rq(rq) ? 0x8 : 0;
 		SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff;
 		SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff;
 		SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff;
@@ -373,6 +373,17 @@ static int sd_init_command(struct scsi_cmnd * SCpnt)
 		SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff;
 		SCpnt->cmnd[8] = (unsigned char) this_count & 0xff;
 	} else {
+		if (unlikely(blk_fua_rq(rq))) {
+			/*
+			 * This happens only if this drive failed
+			 * 10byte rw command with ILLEGAL_REQUEST
+			 * during operation and thus turned off
+			 * use_10_for_rw.
+			 */
+			printk(KERN_ERR "sd: FUA write on READ/WRITE(6) drive\n");
+			return 0;
+		}
+
 		SCpnt->cmnd[1] |= (unsigned char) ((block >> 16) & 0x1f);
 		SCpnt->cmnd[2] = (unsigned char) ((block >> 8) & 0xff);
 		SCpnt->cmnd[3] = (unsigned char) block & 0xff;
@@ -729,42 +740,13 @@ static int sd_issue_flush(struct device *dev, sector_t *error_sector)
 	return ret;
 }
 
-static void sd_end_flush(request_queue_t *q, struct request *flush_rq)
-{
-	struct request *rq = flush_rq->end_io_data;
-	struct scsi_cmnd *cmd = rq->special;
-	unsigned int bytes = rq->hard_nr_sectors << 9;
-
-	if (!flush_rq->errors) {
-		spin_unlock(q->queue_lock);
-		scsi_io_completion(cmd, bytes, 0);
-		spin_lock(q->queue_lock);
-	} else if (blk_barrier_postflush(rq)) {
-		spin_unlock(q->queue_lock);
-		scsi_io_completion(cmd, 0, bytes);
-		spin_lock(q->queue_lock);
-	} else {
-		/*
-		 * force journal abort of barriers
-		 */
-		end_that_request_first(rq, -EOPNOTSUPP, rq->hard_nr_sectors);
-		end_that_request_last(rq);
-	}
-}
-
-static int sd_prepare_flush(request_queue_t *q, struct request *rq)
+static void sd_prepare_flush(request_queue_t *q, struct request *rq)
 {
-	struct scsi_device *sdev = q->queuedata;
-	struct scsi_disk *sdkp = dev_get_drvdata(&sdev->sdev_gendev);
-
-	if (!sdkp || !sdkp->WCE)
-		return 0;
-
 	memset(rq->cmd, 0, sizeof(rq->cmd));
-	rq->flags |= REQ_BLOCK_PC | REQ_SOFTBARRIER;
+	rq->flags |= REQ_BLOCK_PC;
 	rq->timeout = SD_TIMEOUT;
 	rq->cmd[0] = SYNCHRONIZE_CACHE;
-	return 1;
+	rq->cmd_len = 10;
 }
 
 static void sd_rescan(struct device *dev)
@@ -1427,10 +1409,18 @@ sd_read_cache_type(struct scsi_disk *sdkp, char *diskname,
 			sdkp->RCD = 0;
 		}
 
+		sdkp->DPOFUA = (data.device_specific & 0x10) != 0;
+		if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) {
+			printk(KERN_NOTICE "SCSI device %s: uses "
+			       "READ/WRITE(6), disabling FUA\n", diskname);
+			sdkp->DPOFUA = 0;
+		}
+
 		ct =  sdkp->RCD + 2*sdkp->WCE;
 
-		printk(KERN_NOTICE "SCSI device %s: drive cache: %s\n",
-		       diskname, types[ct]);
+		printk(KERN_NOTICE "SCSI device %s: drive cache: %s%s\n",
+		       diskname, types[ct],
+		       sdkp->DPOFUA ? " w/ FUA" : "");
 
 		return;
 	}
@@ -1462,6 +1452,7 @@ static int sd_revalidate_disk(struct gendisk *disk)
 	struct scsi_disk *sdkp = scsi_disk(disk);
 	struct scsi_device *sdp = sdkp->device;
 	unsigned char *buffer;
+	unsigned ordered;
 
 	SCSI_LOG_HLQUEUE(3, printk("sd_revalidate_disk: disk=%s\n", disk->disk_name));
 
@@ -1498,7 +1489,21 @@ static int sd_revalidate_disk(struct gendisk *disk)
 		sd_read_write_protect_flag(sdkp, disk->disk_name, buffer);
 		sd_read_cache_type(sdkp, disk->disk_name, buffer);
 	}
-		
+
+	/*
+	 * We now have all cache related info, determine how we deal
+	 * with ordered requests.  Note that as the current SCSI
+	 * dispatch function can alter request order, we cannot use
+	 * QUEUE_ORDERED_TAG_* even when ordered tag is supported.
+	 */
+	if (sdkp->WCE)
+		ordered = sdkp->DPOFUA
+			? QUEUE_ORDERED_DRAIN_FUA : QUEUE_ORDERED_DRAIN_FLUSH;
+	else
+		ordered = QUEUE_ORDERED_DRAIN;
+
+	blk_queue_ordered(sdkp->disk->queue, ordered, sd_prepare_flush);
+
 	set_capacity(disk, sdkp->capacity);
 	kfree(buffer);
 
@@ -1598,6 +1603,7 @@ static int sd_probe(struct device *dev)
 	strcpy(gd->devfs_name, sdp->devfs_name);
 
 	gd->private_data = &sdkp->driver;
+	gd->queue = sdkp->device->request_queue;
 
 	sd_revalidate_disk(gd);
 
@@ -1605,7 +1611,6 @@ static int sd_probe(struct device *dev)
 	gd->flags = GENHD_FL_DRIVERFS;
 	if (sdp->removable)
 		gd->flags |= GENHD_FL_REMOVABLE;
-	gd->queue = sdkp->device->request_queue;
 
 	dev_set_drvdata(dev, sdkp);
 	add_disk(gd);

fs/bio.c

@@ -325,10 +325,31 @@ static int __bio_add_page(request_queue_t *q, struct bio *bio, struct page
 	if (unlikely(bio_flagged(bio, BIO_CLONED)))
 		return 0;
 
-	if (bio->bi_vcnt >= bio->bi_max_vecs)
+	if (((bio->bi_size + len) >> 9) > max_sectors)
 		return 0;
 
-	if (((bio->bi_size + len) >> 9) > max_sectors)
+	/*
+	 * For filesystems with a blocksize smaller than the pagesize
+	 * we will often be called with the same page as last time and
+	 * a consecutive offset.  Optimize this special case.
+	 */
+	if (bio->bi_vcnt > 0) {
+		struct bio_vec *prev = &bio->bi_io_vec[bio->bi_vcnt - 1];
+
+		if (page == prev->bv_page &&
+		    offset == prev->bv_offset + prev->bv_len) {
+			prev->bv_len += len;
+			if (q->merge_bvec_fn &&
+			    q->merge_bvec_fn(q, bio, prev) < len) {
+				prev->bv_len -= len;
+				return 0;
+			}
+
+			goto done;
+		}
+	}
+
+	if (bio->bi_vcnt >= bio->bi_max_vecs)
 		return 0;
 
 	/*
@@ -382,6 +403,7 @@ static int __bio_add_page(request_queue_t *q, struct bio *bio, struct page
 	bio->bi_vcnt++;
 	bio->bi_phys_segments++;
 	bio->bi_hw_segments++;
+ done:
 	bio->bi_size += len;
 	return len;
 }

include/linux/ata.h

@@ -129,6 +129,7 @@ enum {
 	ATA_CMD_READ_EXT	= 0x25,
 	ATA_CMD_WRITE		= 0xCA,
 	ATA_CMD_WRITE_EXT	= 0x35,
+	ATA_CMD_WRITE_FUA_EXT	= 0x3D,
 	ATA_CMD_PIO_READ	= 0x20,
 	ATA_CMD_PIO_READ_EXT	= 0x24,
 	ATA_CMD_PIO_WRITE	= 0x30,
@@ -137,6 +138,7 @@ enum {
 	ATA_CMD_READ_MULTI_EXT	= 0x29,
 	ATA_CMD_WRITE_MULTI	= 0xC5,
 	ATA_CMD_WRITE_MULTI_EXT	= 0x39,
+	ATA_CMD_WRITE_MULTI_FUA_EXT = 0xCE,
 	ATA_CMD_SET_FEATURES	= 0xEF,
 	ATA_CMD_PACKET		= 0xA0,
 	ATA_CMD_VERIFY		= 0x40,
@@ -194,6 +196,7 @@ enum {
 	ATA_TFLAG_DEVICE	= (1 << 2), /* enable r/w to device reg */
 	ATA_TFLAG_WRITE		= (1 << 3), /* data dir: host->dev==1 (write) */
 	ATA_TFLAG_LBA		= (1 << 4), /* enable LBA */
+	ATA_TFLAG_FUA		= (1 << 5), /* enable FUA */
 };
 
 enum ata_tf_protocols {
@@ -247,7 +250,8 @@ struct ata_taskfile {
 #define ata_id_is_sata(id)	((id)[93] == 0)
 #define ata_id_rahead_enabled(id) ((id)[85] & (1 << 6))
 #define ata_id_wcache_enabled(id) ((id)[85] & (1 << 5))
-#define ata_id_has_flush(id) ((id)[83] & (1 << 12))
+#define ata_id_has_fua(id)	((id)[84] & (1 << 6))
+#define ata_id_has_flush(id)	((id)[83] & (1 << 12))
 #define ata_id_has_flush_ext(id) ((id)[83] & (1 << 13))
 #define ata_id_has_lba48(id)	((id)[83] & (1 << 10))
 #define ata_id_has_wcache(id)	((id)[82] & (1 << 5))

include/linux/blkdev.h

@@ -102,7 +102,7 @@ void copy_io_context(struct io_context **pdst, struct io_context **psrc);
 void swap_io_context(struct io_context **ioc1, struct io_context **ioc2);
 
 struct request;
-typedef void (rq_end_io_fn)(struct request *);
+typedef void (rq_end_io_fn)(struct request *, int);
 
 struct request_list {
 	int count[2];
@@ -207,6 +207,7 @@ enum rq_flag_bits {
 	__REQ_SORTED,		/* elevator knows about this request */
 	__REQ_SOFTBARRIER,	/* may not be passed by ioscheduler */
 	__REQ_HARDBARRIER,	/* may not be passed by drive either */
+	__REQ_FUA,		/* forced unit access */
 	__REQ_CMD,		/* is a regular fs rw request */
 	__REQ_NOMERGE,		/* don't touch this for merging */
 	__REQ_STARTED,		/* drive already may have started this one */
@@ -230,9 +231,7 @@ enum rq_flag_bits {
 	__REQ_PM_SUSPEND,	/* suspend request */
 	__REQ_PM_RESUME,	/* resume request */
 	__REQ_PM_SHUTDOWN,	/* shutdown request */
-	__REQ_BAR_PREFLUSH,	/* barrier pre-flush done */
-	__REQ_BAR_POSTFLUSH,	/* barrier post-flush */
-	__REQ_BAR_FLUSH,	/* rq is the flush request */
+	__REQ_ORDERED_COLOR,	/* is before or after barrier */
 	__REQ_NR_BITS,		/* stops here */
 };
 
@@ -241,6 +240,7 @@ enum rq_flag_bits {
 #define REQ_SORTED	(1 << __REQ_SORTED)
 #define REQ_SOFTBARRIER	(1 << __REQ_SOFTBARRIER)
 #define REQ_HARDBARRIER	(1 << __REQ_HARDBARRIER)
+#define REQ_FUA		(1 << __REQ_FUA)
 #define REQ_CMD		(1 << __REQ_CMD)
 #define REQ_NOMERGE	(1 << __REQ_NOMERGE)
 #define REQ_STARTED	(1 << __REQ_STARTED)
@@ -260,9 +260,7 @@ enum rq_flag_bits {
 #define REQ_PM_SUSPEND	(1 << __REQ_PM_SUSPEND)
 #define REQ_PM_RESUME	(1 << __REQ_PM_RESUME)
 #define REQ_PM_SHUTDOWN	(1 << __REQ_PM_SHUTDOWN)
-#define REQ_BAR_PREFLUSH	(1 << __REQ_BAR_PREFLUSH)
-#define REQ_BAR_POSTFLUSH	(1 << __REQ_BAR_POSTFLUSH)
-#define REQ_BAR_FLUSH	(1 << __REQ_BAR_FLUSH)
+#define REQ_ORDERED_COLOR	(1 << __REQ_ORDERED_COLOR)
 
 /*
  * State information carried for REQ_PM_SUSPEND and REQ_PM_RESUME
@@ -292,8 +290,7 @@ struct bio_vec;
 typedef int (merge_bvec_fn) (request_queue_t *, struct bio *, struct bio_vec *);
 typedef void (activity_fn) (void *data, int rw);
 typedef int (issue_flush_fn) (request_queue_t *, struct gendisk *, sector_t *);
-typedef int (prepare_flush_fn) (request_queue_t *, struct request *);
-typedef void (end_flush_fn) (request_queue_t *, struct request *);
+typedef void (prepare_flush_fn) (request_queue_t *, struct request *);
 
 enum blk_queue_state {
 	Queue_down,
@@ -335,7 +332,6 @@ struct request_queue
 	activity_fn		*activity_fn;
 	issue_flush_fn		*issue_flush_fn;
 	prepare_flush_fn	*prepare_flush_fn;
-	end_flush_fn		*end_flush_fn;
 
 	/*
 	 * Dispatch queue sorting
@@ -420,14 +416,11 @@ struct request_queue
 	/*
 	 * reserved for flush operations
 	 */
-	struct request		*flush_rq;
-	unsigned char		ordered;
-};
-
-enum {
-	QUEUE_ORDERED_NONE,
-	QUEUE_ORDERED_TAG,
-	QUEUE_ORDERED_FLUSH,
+	unsigned int		ordered, next_ordered, ordseq;
+	int			orderr, ordcolor;
+	struct request		pre_flush_rq, bar_rq, post_flush_rq;
+	struct request		*orig_bar_rq;
+	unsigned int		bi_size;
 };
 
 #define RQ_INACTIVE		(-1)
@@ -445,12 +438,51 @@ enum {
 #define QUEUE_FLAG_REENTER	6	/* Re-entrancy avoidance */
 #define QUEUE_FLAG_PLUGGED	7	/* queue is plugged */
 #define QUEUE_FLAG_ELVSWITCH	8	/* don't use elevator, just do FIFO */
-#define QUEUE_FLAG_FLUSH	9	/* doing barrier flush sequence */
+
+enum {
+	/*
+	 * Hardbarrier is supported with one of the following methods.
+	 *
+	 * NONE		: hardbarrier unsupported
+	 * DRAIN	: ordering by draining is enough
+	 * DRAIN_FLUSH	: ordering by draining w/ pre and post flushes
+	 * DRAIN_FUA	: ordering by draining w/ pre flush and FUA write
+	 * TAG		: ordering by tag is enough
+	 * TAG_FLUSH	: ordering by tag w/ pre and post flushes
+	 * TAG_FUA	: ordering by tag w/ pre flush and FUA write
+	 */
+	QUEUE_ORDERED_NONE	= 0x00,
+	QUEUE_ORDERED_DRAIN	= 0x01,
+	QUEUE_ORDERED_TAG	= 0x02,
+
+	QUEUE_ORDERED_PREFLUSH	= 0x10,
+	QUEUE_ORDERED_POSTFLUSH	= 0x20,
+	QUEUE_ORDERED_FUA	= 0x40,
+
+	QUEUE_ORDERED_DRAIN_FLUSH = QUEUE_ORDERED_DRAIN |
+			QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_POSTFLUSH,
+	QUEUE_ORDERED_DRAIN_FUA	= QUEUE_ORDERED_DRAIN |
+			QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_FUA,
+	QUEUE_ORDERED_TAG_FLUSH	= QUEUE_ORDERED_TAG |
+			QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_POSTFLUSH,
+	QUEUE_ORDERED_TAG_FUA	= QUEUE_ORDERED_TAG |
+			QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_FUA,
+
+	/*
+	 * Ordered operation sequence
+	 */
+	QUEUE_ORDSEQ_STARTED	= 0x01,	/* flushing in progress */
+	QUEUE_ORDSEQ_DRAIN	= 0x02,	/* waiting for the queue to be drained */
+	QUEUE_ORDSEQ_PREFLUSH	= 0x04,	/* pre-flushing in progress */
+	QUEUE_ORDSEQ_BAR	= 0x08,	/* original barrier req in progress */
+	QUEUE_ORDSEQ_POSTFLUSH	= 0x10,	/* post-flushing in progress */
+	QUEUE_ORDSEQ_DONE	= 0x20,
+};
 
 #define blk_queue_plugged(q)	test_bit(QUEUE_FLAG_PLUGGED, &(q)->queue_flags)
 #define blk_queue_tagged(q)	test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
 #define blk_queue_stopped(q)	test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
-#define blk_queue_flushing(q)	test_bit(QUEUE_FLAG_FLUSH, &(q)->queue_flags)
+#define blk_queue_flushing(q)	((q)->ordseq)
 
 #define blk_fs_request(rq)	((rq)->flags & REQ_CMD)
 #define blk_pc_request(rq)	((rq)->flags & REQ_BLOCK_PC)
@@ -466,8 +498,7 @@ enum {
 
 #define blk_sorted_rq(rq)	((rq)->flags & REQ_SORTED)
 #define blk_barrier_rq(rq)	((rq)->flags & REQ_HARDBARRIER)
-#define blk_barrier_preflush(rq)	((rq)->flags & REQ_BAR_PREFLUSH)
-#define blk_barrier_postflush(rq)	((rq)->flags & REQ_BAR_POSTFLUSH)
+#define blk_fua_rq(rq)		((rq)->flags & REQ_FUA)
 
 #define list_entry_rq(ptr)	list_entry((ptr), struct request, queuelist)
 
@@ -560,7 +591,7 @@ extern void register_disk(struct gendisk *dev);
 extern void generic_make_request(struct bio *bio);
 extern void blk_put_request(struct request *);
 extern void __blk_put_request(request_queue_t *, struct request *);
-extern void blk_end_sync_rq(struct request *rq);
+extern void blk_end_sync_rq(struct request *rq, int error);
 extern void blk_attempt_remerge(request_queue_t *, struct request *);
 extern struct request *blk_get_request(request_queue_t *, int, gfp_t);
 extern void blk_insert_request(request_queue_t *, struct request *, int, void *);
@@ -582,8 +613,7 @@ extern int blk_rq_map_user_iov(request_queue_t *, struct request *, struct sg_io
 extern int blk_execute_rq(request_queue_t *, struct gendisk *,
 			  struct request *, int);
 extern void blk_execute_rq_nowait(request_queue_t *, struct gendisk *,
-				  struct request *, int,
-				  void (*done)(struct request *));
+				  struct request *, int, rq_end_io_fn *);
 
 static inline request_queue_t *bdev_get_queue(struct block_device *bdev)
 {
@@ -614,7 +644,7 @@ static inline void blk_run_address_space(struct address_space *mapping)
  */
 extern int end_that_request_first(struct request *, int, int);
 extern int end_that_request_chunk(struct request *, int, int);
-extern void end_that_request_last(struct request *);
+extern void end_that_request_last(struct request *, int);
 extern void end_request(struct request *req, int uptodate);
 
 /*
@@ -665,11 +695,12 @@ extern void blk_queue_prep_rq(request_queue_t *, prep_rq_fn *pfn);
 extern void blk_queue_merge_bvec(request_queue_t *, merge_bvec_fn *);
 extern void blk_queue_dma_alignment(request_queue_t *, int);
 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
-extern void blk_queue_ordered(request_queue_t *, int);
+extern int blk_queue_ordered(request_queue_t *, unsigned, prepare_flush_fn *);
 extern void blk_queue_issue_flush_fn(request_queue_t *, issue_flush_fn *);
-extern struct request *blk_start_pre_flush(request_queue_t *,struct request *);
-extern int blk_complete_barrier_rq(request_queue_t *, struct request *, int);
-extern int blk_complete_barrier_rq_locked(request_queue_t *, struct request *, int);
+extern int blk_do_ordered(request_queue_t *, struct request **);
+extern unsigned blk_ordered_cur_seq(request_queue_t *);
+extern unsigned blk_ordered_req_seq(struct request *);
+extern void blk_ordered_complete_seq(request_queue_t *, unsigned, int);
 
 extern int blk_rq_map_sg(request_queue_t *, struct request *, struct scatterlist *);
 extern void blk_dump_rq_flags(struct request *, char *);

include/linux/elevator.h

@@ -130,6 +130,7 @@ extern int elv_try_last_merge(request_queue_t *, struct bio *);
 #define ELEVATOR_INSERT_FRONT	1
 #define ELEVATOR_INSERT_BACK	2
 #define ELEVATOR_INSERT_SORT	3
+#define ELEVATOR_INSERT_REQUEUE	4
 
 /*
  * return values from elevator_may_queue_fn

include/linux/libata.h

@@ -488,7 +488,8 @@ extern u8   ata_bmdma_status(struct ata_port *ap);
 extern void ata_bmdma_irq_clear(struct ata_port *ap);
 extern void ata_qc_complete(struct ata_queued_cmd *qc);
 extern void ata_eng_timeout(struct ata_port *ap);
-extern void ata_scsi_simulate(u16 *id, struct scsi_cmnd *cmd,
+extern void ata_scsi_simulate(struct ata_port *ap, struct ata_device *dev,
+			      struct scsi_cmnd *cmd,
 			      void (*done)(struct scsi_cmnd *));
 extern int ata_std_bios_param(struct scsi_device *sdev,
 			      struct block_device *bdev,

include/scsi/scsi_driver.h

@@ -15,7 +15,6 @@ struct scsi_driver {
 	void (*rescan)(struct device *);
 	int (*issue_flush)(struct device *, sector_t *);
 	int (*prepare_flush)(struct request_queue *, struct request *);
-	void (*end_flush)(struct request_queue *, struct request *);
 };
 #define to_scsi_driver(drv) \
 	container_of((drv), struct scsi_driver, gendrv)

include/scsi/scsi_host.h

@@ -398,7 +398,6 @@ struct scsi_host_template {
 	/*
 	 * ordered write support
 	 */
-	unsigned ordered_flush:1;
 	unsigned ordered_tag:1;
 
 	/*