Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-2.6-block

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-2.6-block:
  ide: always ensure that blk_delay_queue() is called if we have pending IO
  block: fix request sorting at unplug
  dm: improve block integrity support
  fs: export empty_aops
  ide: ide_requeue_and_plug() reinstate "always plug" behaviour
  blk-throttle: don't call xchg on bool
  ufs: remove unessecary blk_flush_plug
  block: make the flush insertion use the tail of the dispatch list
  block: get rid of elv_insert() interface
  block: dump request state on seeing a corrupted request completion

14 files changed, 148 insertions, 91 deletions

diff --git a/block/blk-core.c b/block/blk-core.c
index e0a062363937..725091d5496d 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -2163,7 +2163,7 @@ bool blk_update_request(struct request *req, int error, unsigned int nr_bytes)
 	 * size, something has gone terribly wrong.
 	 */
 	if (blk_rq_bytes(req) < blk_rq_cur_bytes(req)) {
-		printk(KERN_ERR "blk: request botched\n");
+		blk_dump_rq_flags(req, "request botched");
 		req->__data_len = blk_rq_cur_bytes(req);
 	}
 
@@ -2665,7 +2665,7 @@ static int plug_rq_cmp(void *priv, struct list_head *a, struct list_head *b)
 	struct request *rqa = container_of(a, struct request, queuelist);
 	struct request *rqb = container_of(b, struct request, queuelist);
 
-	return !(rqa->q == rqb->q);
+	return !(rqa->q <= rqb->q);
 }
 
 static void flush_plug_list(struct blk_plug *plug)
diff --git a/block/blk-flush.c b/block/blk-flush.c
index 93d5fd8e51eb..eba4a2790c6c 100644
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -261,7 +261,7 @@ static bool blk_kick_flush(struct request_queue *q)
 	q->flush_rq.end_io = flush_end_io;
 
 	q->flush_pending_idx ^= 1;
-	elv_insert(q, &q->flush_rq, ELEVATOR_INSERT_REQUEUE);
+	list_add_tail(&q->flush_rq.queuelist, &q->queue_head);
 	return true;
 }
 
@@ -281,7 +281,7 @@ static void flush_data_end_io(struct request *rq, int error)
  * blk_insert_flush - insert a new FLUSH/FUA request
  * @rq: request to insert
  *
- * To be called from elv_insert() for %ELEVATOR_INSERT_FLUSH insertions.
+ * To be called from __elv_add_request() for %ELEVATOR_INSERT_FLUSH insertions.
  * @rq is being submitted.  Analyze what needs to be done and put it on the
  * right queue.
  *
@@ -312,7 +312,7 @@ void blk_insert_flush(struct request *rq)
 	 */
 	if ((policy & REQ_FSEQ_DATA) &&
 	    !(policy & (REQ_FSEQ_PREFLUSH | REQ_FSEQ_POSTFLUSH))) {
-		list_add(&rq->queuelist, &q->queue_head);
+		list_add_tail(&rq->queuelist, &q->queue_head);
 		return;
 	}
 
diff --git a/block/blk-integrity.c b/block/blk-integrity.c
index 54bcba6c02a7..129b9e209a3b 100644
--- a/block/blk-integrity.c
+++ b/block/blk-integrity.c
@@ -30,6 +30,8 @@
 
 static struct kmem_cache *integrity_cachep;
 
+static const char *bi_unsupported_name = "unsupported";
+
 /**
  * blk_rq_count_integrity_sg - Count number of integrity scatterlist elements
  * @q:		request queue
@@ -358,6 +360,14 @@ static struct kobj_type integrity_ktype = {
 	.release	= blk_integrity_release,
 };
 
+bool blk_integrity_is_initialized(struct gendisk *disk)
+{
+	struct blk_integrity *bi = blk_get_integrity(disk);
+
+	return (bi && bi->name && strcmp(bi->name, bi_unsupported_name) != 0);
+}
+EXPORT_SYMBOL(blk_integrity_is_initialized);
+
 /**
  * blk_integrity_register - Register a gendisk as being integrity-capable
  * @disk:	struct gendisk pointer to make integrity-aware
@@ -407,7 +417,7 @@ int blk_integrity_register(struct gendisk *disk, struct blk_integrity *template)
 		bi->get_tag_fn = template->get_tag_fn;
 		bi->tag_size = template->tag_size;
 	} else
-		bi->name = "unsupported";
+		bi->name = bi_unsupported_name;
 
 	return 0;
 }
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 5352bdafbcf0..6c98cfeeedf0 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -77,7 +77,7 @@ struct throtl_grp {
 	unsigned long slice_end[2];
 
 	/* Some throttle limits got updated for the group */
-	bool limits_changed;
+	int limits_changed;
 };
 
 struct throtl_data
@@ -102,7 +102,7 @@ struct throtl_data
 	/* Work for dispatching throttled bios */
 	struct delayed_work throtl_work;
 
-	bool limits_changed;
+	int limits_changed;
 };
 
 enum tg_state_flags {
diff --git a/block/elevator.c b/block/elevator.c
index c387d3168734..0cdb4e7ebab4 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -610,7 +610,7 @@ void elv_requeue_request(struct request_queue *q, struct request *rq)
 
 	rq->cmd_flags &= ~REQ_STARTED;
 
-	elv_insert(q, rq, ELEVATOR_INSERT_REQUEUE);
+	__elv_add_request(q, rq, ELEVATOR_INSERT_REQUEUE);
 }
 
 void elv_drain_elevator(struct request_queue *q)
@@ -655,12 +655,25 @@ void elv_quiesce_end(struct request_queue *q)
 	queue_flag_clear(QUEUE_FLAG_ELVSWITCH, q);
 }
 
-void elv_insert(struct request_queue *q, struct request *rq, int where)
+void __elv_add_request(struct request_queue *q, struct request *rq, int where)
 {
 	trace_block_rq_insert(q, rq);
 
 	rq->q = q;
 
+	BUG_ON(rq->cmd_flags & REQ_ON_PLUG);
+
+	if (rq->cmd_flags & REQ_SOFTBARRIER) {
+		/* barriers are scheduling boundary, update end_sector */
+		if (rq->cmd_type == REQ_TYPE_FS ||
+		    (rq->cmd_flags & REQ_DISCARD)) {
+			q->end_sector = rq_end_sector(rq);
+			q->boundary_rq = rq;
+		}
+	} else if (!(rq->cmd_flags & REQ_ELVPRIV) &&
+		    where == ELEVATOR_INSERT_SORT)
+		where = ELEVATOR_INSERT_BACK;
+
 	switch (where) {
 	case ELEVATOR_INSERT_REQUEUE:
 	case ELEVATOR_INSERT_FRONT:
@@ -722,24 +735,6 @@ void elv_insert(struct request_queue *q, struct request *rq, int where)
 		BUG();
 	}
 }
-
-void __elv_add_request(struct request_queue *q, struct request *rq, int where)
-{
-	BUG_ON(rq->cmd_flags & REQ_ON_PLUG);
-
-	if (rq->cmd_flags & REQ_SOFTBARRIER) {
-		/* barriers are scheduling boundary, update end_sector */
-		if (rq->cmd_type == REQ_TYPE_FS ||
-		    (rq->cmd_flags & REQ_DISCARD)) {
-			q->end_sector = rq_end_sector(rq);
-			q->boundary_rq = rq;
-		}
-	} else if (!(rq->cmd_flags & REQ_ELVPRIV) &&
-		    where == ELEVATOR_INSERT_SORT)
-		where = ELEVATOR_INSERT_BACK;
-
-	elv_insert(q, rq, where);
-}
 EXPORT_SYMBOL(__elv_add_request);
 
 void elv_add_request(struct request_queue *q, struct request *rq, int where)
diff --git a/drivers/ide/ide-io.c b/drivers/ide/ide-io.c
index 0e406d73b2c8..177db6d5b2f5 100644
--- a/drivers/ide/ide-io.c
+++ b/drivers/ide/ide-io.c
@@ -430,6 +430,26 @@ static inline void ide_unlock_host(struct ide_host *host)
 	}
 }
 
+static void __ide_requeue_and_plug(struct request_queue *q, struct request *rq)
+{
+	if (rq)
+		blk_requeue_request(q, rq);
+	if (rq || blk_peek_request(q)) {
+		/* Use 3ms as that was the old plug delay */
+		blk_delay_queue(q, 3);
+	}
+}
+
+void ide_requeue_and_plug(ide_drive_t *drive, struct request *rq)
+{
+	struct request_queue *q = drive->queue;
+	unsigned long flags;
+
+	spin_lock_irqsave(q->queue_lock, flags);
+	__ide_requeue_and_plug(q, rq);
+	spin_unlock_irqrestore(q->queue_lock, flags);
+}
+
 /*
  * Issue a new request to a device.
  */
@@ -550,28 +570,7 @@ plug_device:
 	ide_unlock_host(host);
 plug_device_2:
 	spin_lock_irq(q->queue_lock);
-
-	if (rq) {
-		blk_requeue_request(q, rq);
-		blk_delay_queue(q, queue_run_ms);
-	}
-}
-
-void ide_requeue_and_plug(ide_drive_t *drive, struct request *rq)
-{
-	struct request_queue *q = drive->queue;
-	unsigned long flags;
-
-	spin_lock_irqsave(q->queue_lock, flags);
-
-	if (rq)
-		blk_requeue_request(q, rq);
-
-	spin_unlock_irqrestore(q->queue_lock, flags);
-
-	/* Use 3ms as that was the old plug delay */
-	if (rq)
-		blk_delay_queue(q, 3);
+	__ide_requeue_and_plug(q, rq);
 }
 
 static int drive_is_ready(ide_drive_t *drive)
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 416d4e258df6..cb8380c9767f 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -927,20 +927,80 @@ static int dm_table_build_index(struct dm_table *t)
 }
 
 /*
+ * Get a disk whose integrity profile reflects the table's profile.
+ * If %match_all is true, all devices' profiles must match.
+ * If %match_all is false, all devices must at least have an
+ * allocated integrity profile; but uninitialized is ok.
+ * Returns NULL if integrity support was inconsistent or unavailable.
+ */
+static struct gendisk * dm_table_get_integrity_disk(struct dm_table *t,
+						    bool match_all)
+{
+	struct list_head *devices = dm_table_get_devices(t);
+	struct dm_dev_internal *dd = NULL;
+	struct gendisk *prev_disk = NULL, *template_disk = NULL;
+
+	list_for_each_entry(dd, devices, list) {
+		template_disk = dd->dm_dev.bdev->bd_disk;
+		if (!blk_get_integrity(template_disk))
+			goto no_integrity;
+		if (!match_all && !blk_integrity_is_initialized(template_disk))
+			continue; /* skip uninitialized profiles */
+		else if (prev_disk &&
+			 blk_integrity_compare(prev_disk, template_disk) < 0)
+			goto no_integrity;
+		prev_disk = template_disk;
+	}
+
+	return template_disk;
+
+no_integrity:
+	if (prev_disk)
+		DMWARN("%s: integrity not set: %s and %s profile mismatch",
+		       dm_device_name(t->md),
+		       prev_disk->disk_name,
+		       template_disk->disk_name);
+	return NULL;
+}
+
+/*
  * Register the mapped device for blk_integrity support if
- * the underlying devices support it.
+ * the underlying devices have an integrity profile.  But all devices
+ * may not have matching profiles (checking all devices isn't reliable
+ * during table load because this table may use other DM device(s) which
+ * must be resumed before they will have an initialized integity profile).
+ * Stacked DM devices force a 2 stage integrity profile validation:
+ * 1 - during load, validate all initialized integrity profiles match
+ * 2 - during resume, validate all integrity profiles match
  */
 static int dm_table_prealloc_integrity(struct dm_table *t, struct mapped_device *md)
 {
-	struct list_head *devices = dm_table_get_devices(t);
-	struct dm_dev_internal *dd;
+	struct gendisk *template_disk = NULL;
 
-	list_for_each_entry(dd, devices, list)
-		if (bdev_get_integrity(dd->dm_dev.bdev)) {
-			t->integrity_supported = 1;
-			return blk_integrity_register(dm_disk(md), NULL);
-		}
+	template_disk = dm_table_get_integrity_disk(t, false);
+	if (!template_disk)
+		return 0;
 
+	if (!blk_integrity_is_initialized(dm_disk(md))) {
+		t->integrity_supported = 1;
+		return blk_integrity_register(dm_disk(md), NULL);
+	}
+
+	/*
+	 * If DM device already has an initalized integrity
+	 * profile the new profile should not conflict.
+	 */
+	if (blk_integrity_is_initialized(template_disk) &&
+	    blk_integrity_compare(dm_disk(md), template_disk) < 0) {
+		DMWARN("%s: conflict with existing integrity profile: "
+		       "%s profile mismatch",
+		       dm_device_name(t->md),
+		       template_disk->disk_name);
+		return 1;
+	}
+
+	/* Preserve existing initialized integrity profile */
+	t->integrity_supported = 1;
 	return 0;
 }
 
@@ -1094,41 +1154,27 @@ combine_limits:
 
 /*
  * Set the integrity profile for this device if all devices used have
- * matching profiles.
+ * matching profiles.  We're quite deep in the resume path but still
+ * don't know if all devices (particularly DM devices this device
+ * may be stacked on) have matching profiles.  Even if the profiles
+ * don't match we have no way to fail (to resume) at this point.
  */
 static void dm_table_set_integrity(struct dm_table *t)
 {
-	struct list_head *devices = dm_table_get_devices(t);
-	struct dm_dev_internal *prev = NULL, *dd = NULL;
+	struct gendisk *template_disk = NULL;
 
 	if (!blk_get_integrity(dm_disk(t->md)))
 		return;
 
-	list_for_each_entry(dd, devices, list) {
-		if (prev &&
-		    blk_integrity_compare(prev->dm_dev.bdev->bd_disk,
-					  dd->dm_dev.bdev->bd_disk) < 0) {
-			DMWARN("%s: integrity not set: %s and %s mismatch",
-			       dm_device_name(t->md),
-			       prev->dm_dev.bdev->bd_disk->disk_name,
-			       dd->dm_dev.bdev->bd_disk->disk_name);
-			goto no_integrity;
-		}
-		prev = dd;
+	template_disk = dm_table_get_integrity_disk(t, true);
+	if (!template_disk &&
+	    blk_integrity_is_initialized(dm_disk(t->md))) {
+		DMWARN("%s: device no longer has a valid integrity profile",
+		       dm_device_name(t->md));
+		return;
 	}
-
-	if (!prev || !bdev_get_integrity(prev->dm_dev.bdev))
-		goto no_integrity;
-
 	blk_integrity_register(dm_disk(t->md),
-			       bdev_get_integrity(prev->dm_dev.bdev));
-
-	return;
-
-no_integrity:
-	blk_integrity_register(dm_disk(t->md), NULL);
-
-	return;
+			       blk_get_integrity(template_disk));
 }
 
 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
diff --git a/fs/inode.c b/fs/inode.c
index 5f4e11aaeb5c..33c963d08ab4 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -125,6 +125,14 @@ __cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_wb_list_lock);
 static DECLARE_RWSEM(iprune_sem);
 
 /*
+ * Empty aops. Can be used for the cases where the user does not
+ * define any of the address_space operations.
+ */
+const struct address_space_operations empty_aops = {
+};
+EXPORT_SYMBOL(empty_aops);
+
+/*
  * Statistics gathering..
  */
 struct inodes_stat_t inodes_stat;
@@ -176,7 +184,6 @@ int proc_nr_inodes(ctl_table *table, int write,
  */
 int inode_init_always(struct super_block *sb, struct inode *inode)
 {
-	static const struct address_space_operations empty_aops;
 	static const struct inode_operations empty_iops;
 	static const struct file_operations empty_fops;
 	struct address_space *const mapping = &inode->i_data;
diff --git a/fs/nilfs2/page.c b/fs/nilfs2/page.c
index 9d2dc6b4348e..1168059c7efd 100644
--- a/fs/nilfs2/page.c
+++ b/fs/nilfs2/page.c
@@ -495,8 +495,6 @@ unsigned nilfs_page_count_clean_buffers(struct page *page,
 void nilfs_mapping_init(struct address_space *mapping,
 			struct backing_dev_info *bdi)
 {
-	static const struct address_space_operations empty_aops;
-
 	mapping->host = NULL;
 	mapping->flags = 0;
 	mapping_set_gfp_mask(mapping, GFP_NOFS);
diff --git a/fs/ubifs/xattr.c b/fs/ubifs/xattr.c
index c74400f88fe0..3299f469e712 100644
--- a/fs/ubifs/xattr.c
+++ b/fs/ubifs/xattr.c
@@ -56,6 +56,7 @@
  */
 
 #include "ubifs.h"
+#include <linux/fs.h>
 #include <linux/slab.h>
 #include <linux/xattr.h>
 #include <linux/posix_acl_xattr.h>
@@ -80,7 +81,6 @@ enum {
 };
 
 static const struct inode_operations none_inode_operations;
-static const struct address_space_operations none_address_operations;
 static const struct file_operations none_file_operations;
 
 /**
@@ -130,7 +130,7 @@ static int create_xattr(struct ubifs_info *c, struct inode *host,
 	}
 
 	/* Re-define all operations to be "nothing" */
-	inode->i_mapping->a_ops = &none_address_operations;
+	inode->i_mapping->a_ops = &empty_aops;
 	inode->i_op = &none_inode_operations;
 	inode->i_fop = &none_file_operations;
 
diff --git a/fs/ufs/truncate.c b/fs/ufs/truncate.c
index 11014302c9ca..5f821dbc0579 100644
--- a/fs/ufs/truncate.c
+++ b/fs/ufs/truncate.c
@@ -479,7 +479,6 @@ int ufs_truncate(struct inode *inode, loff_t old_i_size)
 			break;
 		if (IS_SYNC(inode) && (inode->i_state & I_DIRTY))
 			ufs_sync_inode (inode);
-		blk_flush_plug(current);
 		yield();
 	}
 
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 16a902f099ac..32176cc8e715 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1206,6 +1206,7 @@ struct blk_integrity {
 	struct kobject		kobj;
 };
 
+extern bool blk_integrity_is_initialized(struct gendisk *);
 extern int blk_integrity_register(struct gendisk *, struct blk_integrity *);
 extern void blk_integrity_unregister(struct gendisk *);
 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
@@ -1262,6 +1263,7 @@ queue_max_integrity_segments(struct request_queue *q)
 #define queue_max_integrity_segments(a)		(0)
 #define blk_integrity_merge_rq(a, b, c)		(0)
 #define blk_integrity_merge_bio(a, b, c)	(0)
+#define blk_integrity_is_initialized(a)		(0)
 
 #endif /* CONFIG_BLK_DEV_INTEGRITY */
 
diff --git a/include/linux/elevator.h b/include/linux/elevator.h
index d93efcc44570..21a8ebf2dc3a 100644
--- a/include/linux/elevator.h
+++ b/include/linux/elevator.h
@@ -101,7 +101,6 @@ extern void elv_dispatch_sort(struct request_queue *, struct request *);
 extern void elv_dispatch_add_tail(struct request_queue *, struct request *);
 extern void elv_add_request(struct request_queue *, struct request *, int);
 extern void __elv_add_request(struct request_queue *, struct request *, int);
-extern void elv_insert(struct request_queue *, struct request *, int);
 extern int elv_merge(struct request_queue *, struct request **, struct bio *);
 extern int elv_try_merge(struct request *, struct bio *);
 extern void elv_merge_requests(struct request_queue *, struct request *,
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 52f283c1edb2..1b95af37e3b3 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -613,6 +613,8 @@ struct address_space_operations {
 	int (*error_remove_page)(struct address_space *, struct page *);
 };
 
+extern const struct address_space_operations empty_aops;
+
 /*
  * pagecache_write_begin/pagecache_write_end must be used by general code
  * to write into the pagecache.