1 files changed, 34 insertions, 114 deletions

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index ab55bfc31a06..f777145203df 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -44,16 +44,6 @@ static int btrfs_relocate_sys_chunks(struct btrfs_root *root);
 static DEFINE_MUTEX(uuid_mutex);
 static LIST_HEAD(fs_uuids);
 
-void btrfs_lock_volumes(void)
-{
-	mutex_lock(&uuid_mutex);
-}
-
-void btrfs_unlock_volumes(void)
-{
-	mutex_unlock(&uuid_mutex);
-}
-
 static void lock_chunks(struct btrfs_root *root)
 {
 	mutex_lock(&root->fs_info->chunk_mutex);
@@ -151,22 +141,25 @@ static noinline int run_scheduled_bios(struct btrfs_device *device)
 	struct bio *cur;
 	int again = 0;
 	unsigned long num_run;
-	unsigned long num_sync_run;
 	unsigned long batch_run = 0;
 	unsigned long limit;
 	unsigned long last_waited = 0;
 	int force_reg = 0;
+	struct blk_plug plug;
+
+	/*
+	 * this function runs all the bios we've collected for
+	 * a particular device.  We don't want to wander off to
+	 * another device without first sending all of these down.
+	 * So, setup a plug here and finish it off before we return
+	 */
+	blk_start_plug(&plug);
 
 	bdi = blk_get_backing_dev_info(device->bdev);
 	fs_info = device->dev_root->fs_info;
 	limit = btrfs_async_submit_limit(fs_info);
 	limit = limit * 2 / 3;
 
-	/* we want to make sure that every time we switch from the sync
-	 * list to the normal list, we unplug
-	 */
-	num_sync_run = 0;
-
 loop:
 	spin_lock(&device->io_lock);
 
@@ -212,15 +205,6 @@ loop_lock:
 
 	spin_unlock(&device->io_lock);
 
-	/*
-	 * if we're doing the regular priority list, make sure we unplug
-	 * for any high prio bios we've sent down
-	 */
-	if (pending_bios == &device->pending_bios && num_sync_run > 0) {
-		num_sync_run = 0;
-		blk_run_backing_dev(bdi, NULL);
-	}
-
 	while (pending) {
 
 		rmb();
@@ -248,19 +232,11 @@ loop_lock:
 
 		BUG_ON(atomic_read(&cur->bi_cnt) == 0);
 
-		if (cur->bi_rw & REQ_SYNC)
-			num_sync_run++;
-
 		submit_bio(cur->bi_rw, cur);
 		num_run++;
 		batch_run++;
-		if (need_resched()) {
-			if (num_sync_run) {
-				blk_run_backing_dev(bdi, NULL);
-				num_sync_run = 0;
-			}
+		if (need_resched())
 			cond_resched();
-		}
 
 		/*
 		 * we made progress, there is more work to do and the bdi
@@ -293,13 +269,8 @@ loop_lock:
 				 * against it before looping
 				 */
 				last_waited = ioc->last_waited;
-				if (need_resched()) {
-					if (num_sync_run) {
-						blk_run_backing_dev(bdi, NULL);
-						num_sync_run = 0;
-					}
+				if (need_resched())
 					cond_resched();
-				}
 				continue;
 			}
 			spin_lock(&device->io_lock);
@@ -312,22 +283,6 @@ loop_lock:
 		}
 	}
 
-	if (num_sync_run) {
-		num_sync_run = 0;
-		blk_run_backing_dev(bdi, NULL);
-	}
-	/*
-	 * IO has already been through a long path to get here.  Checksumming,
-	 * async helper threads, perhaps compression.  We've done a pretty
-	 * good job of collecting a batch of IO and should just unplug
-	 * the device right away.
-	 *
-	 * This will help anyone who is waiting on the IO, they might have
-	 * already unplugged, but managed to do so before the bio they
-	 * cared about found its way down here.
-	 */
-	blk_run_backing_dev(bdi, NULL);
-
 	cond_resched();
 	if (again)
 		goto loop;
@@ -338,6 +293,7 @@ loop_lock:
 	spin_unlock(&device->io_lock);
 
 done:
+	blk_finish_plug(&plug);
 	return 0;
 }
 
@@ -1506,7 +1462,7 @@ next_slot:
 				goto error;
 			leaf = path->nodes[0];
 			btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
-			btrfs_release_path(root, path);
+			btrfs_release_path(path);
 			continue;
 		}
 
@@ -1978,7 +1934,7 @@ again:
 		chunk = btrfs_item_ptr(leaf, path->slots[0],
 				       struct btrfs_chunk);
 		chunk_type = btrfs_chunk_type(leaf, chunk);
-		btrfs_release_path(chunk_root, path);
+		btrfs_release_path(path);
 
 		if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
 			ret = btrfs_relocate_chunk(chunk_root, chunk_tree,
@@ -2096,7 +2052,7 @@ int btrfs_balance(struct btrfs_root *dev_root)
 		if (found_key.offset == 0)
 			break;
 
-		btrfs_release_path(chunk_root, path);
+		btrfs_release_path(path);
 		ret = btrfs_relocate_chunk(chunk_root,
 					   chunk_root->root_key.objectid,
 					   found_key.objectid,
@@ -2168,7 +2124,7 @@ again:
 			goto done;
 		if (ret) {
 			ret = 0;
-			btrfs_release_path(root, path);
+			btrfs_release_path(path);
 			break;
 		}
 
@@ -2177,7 +2133,7 @@ again:
 		btrfs_item_key_to_cpu(l, &key, path->slots[0]);
 
 		if (key.objectid != device->devid) {
-			btrfs_release_path(root, path);
+			btrfs_release_path(path);
 			break;
 		}
 
@@ -2185,14 +2141,14 @@ again:
 		length = btrfs_dev_extent_length(l, dev_extent);
 
 		if (key.offset + length <= new_size) {
-			btrfs_release_path(root, path);
+			btrfs_release_path(path);
 			break;
 		}
 
 		chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent);
 		chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
 		chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
-		btrfs_release_path(root, path);
+		btrfs_release_path(path);
 
 		ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid,
 					   chunk_offset);
@@ -2497,7 +2453,7 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 
 	trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes);
 
-	em = alloc_extent_map(GFP_NOFS);
+	em = alloc_extent_map();
 	if (!em) {
 		ret = -ENOMEM;
 		goto error;
@@ -2738,7 +2694,7 @@ int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
 
 void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
 {
-	extent_map_tree_init(&tree->map_tree, GFP_NOFS);
+	extent_map_tree_init(&tree->map_tree);
 }
 
 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
@@ -2804,7 +2760,7 @@ static int find_live_mirror(struct map_lookup *map, int first, int num,
 static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
 			     u64 logical, u64 *length,
 			     struct btrfs_multi_bio **multi_ret,
-			     int mirror_num, struct page *unplug_page)
+			     int mirror_num)
 {
 	struct extent_map *em;
 	struct map_lookup *map;
@@ -2839,11 +2795,6 @@ again:
 	em = lookup_extent_mapping(em_tree, logical, *length);
 	read_unlock(&em_tree->lock);
 
-	if (!em && unplug_page) {
-		kfree(multi);
-		return 0;
-	}
-
 	if (!em) {
 		printk(KERN_CRIT "unable to find logical %llu len %llu\n",
 		       (unsigned long long)logical,
@@ -2910,7 +2861,7 @@ again:
 		*length = em->len - offset;
 	}
 
-	if (!multi_ret && !unplug_page)
+	if (!multi_ret)
 		goto out;
 
 	num_stripes = 1;
@@ -2927,7 +2878,7 @@ again:
 					    stripe_nr_end - stripe_nr_orig);
 		stripe_index = do_div(stripe_nr, map->num_stripes);
 	} else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
-		if (unplug_page || (rw & (REQ_WRITE | REQ_DISCARD)))
+		if (rw & (REQ_WRITE | REQ_DISCARD))
 			num_stripes = map->num_stripes;
 		else if (mirror_num)
 			stripe_index = mirror_num - 1;
@@ -2949,7 +2900,7 @@ again:
 		stripe_index = do_div(stripe_nr, factor);
 		stripe_index *= map->sub_stripes;
 
-		if (unplug_page || (rw & REQ_WRITE))
+		if (rw & REQ_WRITE)
 			num_stripes = map->sub_stripes;
 		else if (rw & REQ_DISCARD)
 			num_stripes = min_t(u64, map->sub_stripes *
@@ -3059,26 +3010,12 @@ again:
 		}
 	} else {
 		for (i = 0; i < num_stripes; i++) {
-			if (unplug_page) {
-				struct btrfs_device *device;
-				struct backing_dev_info *bdi;
-
-				device = map->stripes[stripe_index].dev;
-				if (device->bdev) {
-					bdi = blk_get_backing_dev_info(device->
-								       bdev);
-					if (bdi->unplug_io_fn)
-						bdi->unplug_io_fn(bdi,
-								  unplug_page);
-				}
-			} else {
-				multi->stripes[i].physical =
-					map->stripes[stripe_index].physical +
-					stripe_offset +
-					stripe_nr * map->stripe_len;
-				multi->stripes[i].dev =
-					map->stripes[stripe_index].dev;
-			}
+			multi->stripes[i].physical =
+				map->stripes[stripe_index].physical +
+				stripe_offset +
+				stripe_nr * map->stripe_len;
+			multi->stripes[i].dev =
+				map->stripes[stripe_index].dev;
 			stripe_index++;
 		}
 	}
@@ -3097,7 +3034,7 @@ int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
 		      struct btrfs_multi_bio **multi_ret, int mirror_num)
 {
 	return __btrfs_map_block(map_tree, rw, logical, length, multi_ret,
-				 mirror_num, NULL);
+				 mirror_num);
 }
 
 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
@@ -3165,14 +3102,6 @@ int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
 	return 0;
 }
 
-int btrfs_unplug_page(struct btrfs_mapping_tree *map_tree,
-		      u64 logical, struct page *page)
-{
-	u64 length = PAGE_CACHE_SIZE;
-	return __btrfs_map_block(map_tree, READ, logical, &length,
-				 NULL, 0, page);
-}
-
 static void end_bio_multi_stripe(struct bio *bio, int err)
 {
 	struct btrfs_multi_bio *multi = bio->bi_private;
@@ -3415,7 +3344,7 @@ static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
 		free_extent_map(em);
 	}
 
-	em = alloc_extent_map(GFP_NOFS);
+	em = alloc_extent_map();
 	if (!em)
 		return -ENOMEM;
 	num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
@@ -3604,15 +3533,6 @@ static int read_one_dev(struct btrfs_root *root,
 	return ret;
 }
 
-int btrfs_read_super_device(struct btrfs_root *root, struct extent_buffer *buf)
-{
-	struct btrfs_dev_item *dev_item;
-
-	dev_item = (struct btrfs_dev_item *)offsetof(struct btrfs_super_block,
-						     dev_item);
-	return read_one_dev(root, buf, dev_item);
-}
-
 int btrfs_read_sys_array(struct btrfs_root *root)
 {
 	struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
@@ -3729,7 +3649,7 @@ again:
 	}
 	if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
 		key.objectid = 0;
-		btrfs_release_path(root, path);
+		btrfs_release_path(path);
 		goto again;
 	}
 	ret = 0;