Merge commit 'v2.6.38-rc5' into core/locking

Merge reason: pick up upstream fixes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

19 files changed, 439 insertions, 127 deletions

diff --git a/fs/btrfs/acl.c b/fs/btrfs/acl.c
index 15b5ca2a260..9c949348510 100644
--- a/fs/btrfs/acl.c
+++ b/fs/btrfs/acl.c
@@ -37,6 +37,9 @@ static struct posix_acl *btrfs_get_acl(struct inode *inode, int type)
 	char *value = NULL;
 	struct posix_acl *acl;
 
+	if (!IS_POSIXACL(inode))
+		return NULL;
+
 	acl = get_cached_acl(inode, type);
 	if (acl != ACL_NOT_CACHED)
 		return acl;
@@ -84,6 +87,9 @@ static int btrfs_xattr_acl_get(struct dentry *dentry, const char *name,
 	struct posix_acl *acl;
 	int ret = 0;
 
+	if (!IS_POSIXACL(dentry->d_inode))
+		return -EOPNOTSUPP;
+
 	acl = btrfs_get_acl(dentry->d_inode, type);
 
 	if (IS_ERR(acl))
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index f745287fbf2..4d2110eafe2 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -562,7 +562,7 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 	u64 em_len;
 	u64 em_start;
 	struct extent_map *em;
-	int ret;
+	int ret = -ENOMEM;
 	u32 *sums;
 
 	tree = &BTRFS_I(inode)->io_tree;
@@ -577,6 +577,9 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 
 	compressed_len = em->block_len;
 	cb = kmalloc(compressed_bio_size(root, compressed_len), GFP_NOFS);
+	if (!cb)
+		goto out;
+
 	atomic_set(&cb->pending_bios, 0);
 	cb->errors = 0;
 	cb->inode = inode;
@@ -597,13 +600,18 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 
 	nr_pages = (compressed_len + PAGE_CACHE_SIZE - 1) /
 				 PAGE_CACHE_SIZE;
-	cb->compressed_pages = kmalloc(sizeof(struct page *) * nr_pages,
+	cb->compressed_pages = kzalloc(sizeof(struct page *) * nr_pages,
 				       GFP_NOFS);
+	if (!cb->compressed_pages)
+		goto fail1;
+
 	bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
 
 	for (page_index = 0; page_index < nr_pages; page_index++) {
 		cb->compressed_pages[page_index] = alloc_page(GFP_NOFS |
 							      __GFP_HIGHMEM);
+		if (!cb->compressed_pages[page_index])
+			goto fail2;
 	}
 	cb->nr_pages = nr_pages;
 
@@ -614,6 +622,8 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 	cb->len = uncompressed_len;
 
 	comp_bio = compressed_bio_alloc(bdev, cur_disk_byte, GFP_NOFS);
+	if (!comp_bio)
+		goto fail2;
 	comp_bio->bi_private = cb;
 	comp_bio->bi_end_io = end_compressed_bio_read;
 	atomic_inc(&cb->pending_bios);
@@ -681,6 +691,17 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 
 	bio_put(comp_bio);
 	return 0;
+
+fail2:
+	for (page_index = 0; page_index < nr_pages; page_index++)
+		free_page((unsigned long)cb->compressed_pages[page_index]);
+
+	kfree(cb->compressed_pages);
+fail1:
+	kfree(cb);
+out:
+	free_extent_map(em);
+	return ret;
 }
 
 static struct list_head comp_idle_workspace[BTRFS_COMPRESS_TYPES];
@@ -900,7 +921,7 @@ int btrfs_decompress(int type, unsigned char *data_in, struct page *dest_page,
 	return ret;
 }
 
-void __exit btrfs_exit_compress(void)
+void btrfs_exit_compress(void)
 {
 	free_workspaces();
 }
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index b531c36455d..e1aa8d607bc 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -359,10 +359,14 @@ static int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
 
 	tree = &BTRFS_I(page->mapping->host)->io_tree;
 
-	if (page->private == EXTENT_PAGE_PRIVATE)
+	if (page->private == EXTENT_PAGE_PRIVATE) {
+		WARN_ON(1);
 		goto out;
-	if (!page->private)
+	}
+	if (!page->private) {
+		WARN_ON(1);
 		goto out;
+	}
 	len = page->private >> 2;
 	WARN_ON(len == 0);
 
@@ -1550,6 +1554,7 @@ static int transaction_kthread(void *arg)
 		spin_unlock(&root->fs_info->new_trans_lock);
 
 		trans = btrfs_join_transaction(root, 1);
+		BUG_ON(IS_ERR(trans));
 		if (transid == trans->transid) {
 			ret = btrfs_commit_transaction(trans, root);
 			BUG_ON(ret);
@@ -2453,10 +2458,14 @@ int btrfs_commit_super(struct btrfs_root *root)
 	up_write(&root->fs_info->cleanup_work_sem);
 
 	trans = btrfs_join_transaction(root, 1);
+	if (IS_ERR(trans))
+		return PTR_ERR(trans);
 	ret = btrfs_commit_transaction(trans, root);
 	BUG_ON(ret);
 	/* run commit again to drop the original snapshot */
 	trans = btrfs_join_transaction(root, 1);
+	if (IS_ERR(trans))
+		return PTR_ERR(trans);
 	btrfs_commit_transaction(trans, root);
 	ret = btrfs_write_and_wait_transaction(NULL, root);
 	BUG_ON(ret);
@@ -2554,6 +2563,8 @@ int close_ctree(struct btrfs_root *root)
 	kfree(fs_info->chunk_root);
 	kfree(fs_info->dev_root);
 	kfree(fs_info->csum_root);
+	kfree(fs_info);
+
 	return 0;
 }
 
diff --git a/fs/btrfs/export.c b/fs/btrfs/export.c
index 9786963b07e..ff27d7a477b 100644
--- a/fs/btrfs/export.c
+++ b/fs/btrfs/export.c
@@ -171,6 +171,8 @@ static struct dentry *btrfs_get_parent(struct dentry *child)
 	int ret;
 
 	path = btrfs_alloc_path();
+	if (!path)
+		return ERR_PTR(-ENOMEM);
 
 	if (dir->i_ino == BTRFS_FIRST_FREE_OBJECTID) {
 		key.objectid = root->root_key.objectid;
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index b55269340ce..f3c96fc0143 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -320,11 +320,6 @@ static int caching_kthread(void *data)
 	if (!path)
 		return -ENOMEM;
 
-	exclude_super_stripes(extent_root, block_group);
-	spin_lock(&block_group->space_info->lock);
-	block_group->space_info->bytes_readonly += block_group->bytes_super;
-	spin_unlock(&block_group->space_info->lock);
-
 	last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
 
 	/*
@@ -467,8 +462,10 @@ static int cache_block_group(struct btrfs_block_group_cache *cache,
 			cache->cached = BTRFS_CACHE_NO;
 		}
 		spin_unlock(&cache->lock);
-		if (ret == 1)
+		if (ret == 1) {
+			free_excluded_extents(fs_info->extent_root, cache);
 			return 0;
+		}
 	}
 
 	if (load_cache_only)
@@ -3344,8 +3341,10 @@ static int shrink_delalloc(struct btrfs_trans_handle *trans,
 	u64 reserved;
 	u64 max_reclaim;
 	u64 reclaimed = 0;
+	long time_left;
 	int pause = 1;
 	int nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT;
+	int loops = 0;
 
 	block_rsv = &root->fs_info->delalloc_block_rsv;
 	space_info = block_rsv->space_info;
@@ -3358,7 +3357,7 @@ static int shrink_delalloc(struct btrfs_trans_handle *trans,
 
 	max_reclaim = min(reserved, to_reclaim);
 
-	while (1) {
+	while (loops < 1024) {
 		/* have the flusher threads jump in and do some IO */
 		smp_mb();
 		nr_pages = min_t(unsigned long, nr_pages,
@@ -3366,8 +3365,12 @@ static int shrink_delalloc(struct btrfs_trans_handle *trans,
 		writeback_inodes_sb_nr_if_idle(root->fs_info->sb, nr_pages);
 
 		spin_lock(&space_info->lock);
-		if (reserved > space_info->bytes_reserved)
+		if (reserved > space_info->bytes_reserved) {
+			loops = 0;
 			reclaimed += reserved - space_info->bytes_reserved;
+		} else {
+			loops++;
+		}
 		reserved = space_info->bytes_reserved;
 		spin_unlock(&space_info->lock);
 
@@ -3378,7 +3381,12 @@ static int shrink_delalloc(struct btrfs_trans_handle *trans,
 			return -EAGAIN;
 
 		__set_current_state(TASK_INTERRUPTIBLE);
-		schedule_timeout(pause);
+		time_left = schedule_timeout(pause);
+
+		/* We were interrupted, exit */
+		if (time_left)
+			break;
+
 		pause <<= 1;
 		if (pause > HZ / 10)
 			pause = HZ / 10;
@@ -3588,8 +3596,20 @@ void block_rsv_release_bytes(struct btrfs_block_rsv *block_rsv,
 
 	if (num_bytes > 0) {
 		if (dest) {
-			block_rsv_add_bytes(dest, num_bytes, 0);
-		} else {
+			spin_lock(&dest->lock);
+			if (!dest->full) {
+				u64 bytes_to_add;
+
+				bytes_to_add = dest->size - dest->reserved;
+				bytes_to_add = min(num_bytes, bytes_to_add);
+				dest->reserved += bytes_to_add;
+				if (dest->reserved >= dest->size)
+					dest->full = 1;
+				num_bytes -= bytes_to_add;
+			}
+			spin_unlock(&dest->lock);
+		}
+		if (num_bytes) {
 			spin_lock(&space_info->lock);
 			space_info->bytes_reserved -= num_bytes;
 			spin_unlock(&space_info->lock);
@@ -4012,6 +4032,7 @@ void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
 
 	num_bytes = ALIGN(num_bytes, root->sectorsize);
 	atomic_dec(&BTRFS_I(inode)->outstanding_extents);
+	WARN_ON(atomic_read(&BTRFS_I(inode)->outstanding_extents) < 0);
 
 	spin_lock(&BTRFS_I(inode)->accounting_lock);
 	nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents);
@@ -5633,6 +5654,7 @@ use_block_rsv(struct btrfs_trans_handle *trans,
 	      struct btrfs_root *root, u32 blocksize)
 {
 	struct btrfs_block_rsv *block_rsv;
+	struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv;
 	int ret;
 
 	block_rsv = get_block_rsv(trans, root);
@@ -5640,14 +5662,39 @@ use_block_rsv(struct btrfs_trans_handle *trans,
 	if (block_rsv->size == 0) {
 		ret = reserve_metadata_bytes(trans, root, block_rsv,
 					     blocksize, 0);
-		if (ret)
+		/*
+		 * If we couldn't reserve metadata bytes try and use some from
+		 * the global reserve.
+		 */
+		if (ret && block_rsv != global_rsv) {
+			ret = block_rsv_use_bytes(global_rsv, blocksize);
+			if (!ret)
+				return global_rsv;
+			return ERR_PTR(ret);
+		} else if (ret) {
 			return ERR_PTR(ret);
+		}
 		return block_rsv;
 	}
 
 	ret = block_rsv_use_bytes(block_rsv, blocksize);
 	if (!ret)
 		return block_rsv;
+	if (ret) {
+		WARN_ON(1);
+		ret = reserve_metadata_bytes(trans, root, block_rsv, blocksize,
+					     0);
+		if (!ret) {
+			spin_lock(&block_rsv->lock);
+			block_rsv->size += blocksize;
+			spin_unlock(&block_rsv->lock);
+			return block_rsv;
+		} else if (ret && block_rsv != global_rsv) {
+			ret = block_rsv_use_bytes(global_rsv, blocksize);
+			if (!ret)
+				return global_rsv;
+		}
+	}
 
 	return ERR_PTR(-ENOSPC);
 }
@@ -6221,6 +6268,8 @@ int btrfs_drop_snapshot(struct btrfs_root *root,
 	BUG_ON(!wc);
 
 	trans = btrfs_start_transaction(tree_root, 0);
+	BUG_ON(IS_ERR(trans));
+
 	if (block_rsv)
 		trans->block_rsv = block_rsv;
 
@@ -6318,6 +6367,7 @@ int btrfs_drop_snapshot(struct btrfs_root *root,
 
 			btrfs_end_transaction_throttle(trans, tree_root);
 			trans = btrfs_start_transaction(tree_root, 0);
+			BUG_ON(IS_ERR(trans));
 			if (block_rsv)
 				trans->block_rsv = block_rsv;
 		}
@@ -6446,6 +6496,8 @@ static noinline int relocate_inode_pages(struct inode *inode, u64 start,
 	int ret = 0;
 
 	ra = kzalloc(sizeof(*ra), GFP_NOFS);
+	if (!ra)
+		return -ENOMEM;
 
 	mutex_lock(&inode->i_mutex);
 	first_index = start >> PAGE_CACHE_SHIFT;
@@ -6531,7 +6583,7 @@ static noinline int relocate_data_extent(struct inode *reloc_inode,
 	u64 end = start + extent_key->offset - 1;
 
 	em = alloc_extent_map(GFP_NOFS);
-	BUG_ON(!em || IS_ERR(em));
+	BUG_ON(!em);
 
 	em->start = start;
 	em->len = extent_key->offset;
@@ -7477,7 +7529,7 @@ int btrfs_drop_dead_reloc_roots(struct btrfs_root *root)
 		BUG_ON(reloc_root->commit_root != NULL);
 		while (1) {
 			trans = btrfs_join_transaction(root, 1);
-			BUG_ON(!trans);
+			BUG_ON(IS_ERR(trans));
 
 			mutex_lock(&root->fs_info->drop_mutex);
 			ret = btrfs_drop_snapshot(trans, reloc_root);
@@ -7535,7 +7587,7 @@ int btrfs_cleanup_reloc_trees(struct btrfs_root *root)
 
 	if (found) {
 		trans = btrfs_start_transaction(root, 1);
-		BUG_ON(!trans);
+		BUG_ON(IS_ERR(trans));
 		ret = btrfs_commit_transaction(trans, root);
 		BUG_ON(ret);
 	}
@@ -7779,7 +7831,7 @@ static noinline int relocate_one_extent(struct btrfs_root *extent_root,
 
 
 	trans = btrfs_start_transaction(extent_root, 1);
-	BUG_ON(!trans);
+	BUG_ON(IS_ERR(trans));
 
 	if (extent_key->objectid == 0) {
 		ret = del_extent_zero(trans, extent_root, path, extent_key);
@@ -8270,6 +8322,13 @@ int btrfs_free_block_groups(struct btrfs_fs_info *info)
 		if (block_group->cached == BTRFS_CACHE_STARTED)
 			wait_block_group_cache_done(block_group);
 
+		/*
+		 * We haven't cached this block group, which means we could
+		 * possibly have excluded extents on this block group.
+		 */
+		if (block_group->cached == BTRFS_CACHE_NO)
+			free_excluded_extents(info->extent_root, block_group);
+
 		btrfs_remove_free_space_cache(block_group);
 		btrfs_put_block_group(block_group);
 
@@ -8385,6 +8444,13 @@ int btrfs_read_block_groups(struct btrfs_root *root)
 		cache->sectorsize = root->sectorsize;
 
 		/*
+		 * We need to exclude the super stripes now so that the space
+		 * info has super bytes accounted for, otherwise we'll think
+		 * we have more space than we actually do.
+		 */
+		exclude_super_stripes(root, cache);
+
+		/*
 		 * check for two cases, either we are full, and therefore
 		 * don't need to bother with the caching work since we won't
 		 * find any space, or we are empty, and we can just add all
@@ -8392,12 +8458,10 @@ int btrfs_read_block_groups(struct btrfs_root *root)
 		 * time, particularly in the full case.
 		 */
 		if (found_key.offset == btrfs_block_group_used(&cache->item)) {
-			exclude_super_stripes(root, cache);
 			cache->last_byte_to_unpin = (u64)-1;
 			cache->cached = BTRFS_CACHE_FINISHED;
 			free_excluded_extents(root, cache);
 		} else if (btrfs_block_group_used(&cache->item) == 0) {
-			exclude_super_stripes(root, cache);
 			cache->last_byte_to_unpin = (u64)-1;
 			cache->cached = BTRFS_CACHE_FINISHED;
 			add_new_free_space(cache, root->fs_info,
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 2e993cf1766..92ac5192c51 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1865,7 +1865,7 @@ static int submit_one_bio(int rw, struct bio *bio, int mirror_num,
 	bio_get(bio);
 
 	if (tree->ops && tree->ops->submit_bio_hook)
-		tree->ops->submit_bio_hook(page->mapping->host, rw, bio,
+		ret = tree->ops->submit_bio_hook(page->mapping->host, rw, bio,
 					   mirror_num, bio_flags, start);
 	else
 		submit_bio(rw, bio);
@@ -1920,6 +1920,8 @@ static int submit_extent_page(int rw, struct extent_io_tree *tree,
 		nr = bio_get_nr_vecs(bdev);
 
 	bio = btrfs_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH);
+	if (!bio)
+		return -ENOMEM;
 
 	bio_add_page(bio, page, page_size, offset);
 	bio->bi_end_io = end_io_func;
@@ -1944,6 +1946,7 @@ void set_page_extent_mapped(struct page *page)
 
 static void set_page_extent_head(struct page *page, unsigned long len)
 {
+	WARN_ON(!PagePrivate(page));
 	set_page_private(page, EXTENT_PAGE_PRIVATE_FIRST_PAGE | len << 2);
 }
 
@@ -2126,7 +2129,7 @@ int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
 	ret = __extent_read_full_page(tree, page, get_extent, &bio, 0,
 				      &bio_flags);
 	if (bio)
-		submit_one_bio(READ, bio, 0, bio_flags);
+		ret = submit_one_bio(READ, bio, 0, bio_flags);
 	return ret;
 }
 
@@ -2819,9 +2822,17 @@ int try_release_extent_state(struct extent_map_tree *map,
 		 * at this point we can safely clear everything except the
 		 * locked bit and the nodatasum bit
 		 */
-		clear_extent_bit(tree, start, end,
+		ret = clear_extent_bit(tree, start, end,
 				 ~(EXTENT_LOCKED | EXTENT_NODATASUM),
 				 0, 0, NULL, mask);
+
+		/* if clear_extent_bit failed for enomem reasons,
+		 * we can't allow the release to continue.
+		 */
+		if (ret < 0)
+			ret = 0;
+		else
+			ret = 1;
 	}
 	return ret;
 }
@@ -3192,7 +3203,13 @@ struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
 		}
 		if (!PageUptodate(p))
 			uptodate = 0;
-		unlock_page(p);
+
+		/*
+		 * see below about how we avoid a nasty race with release page
+		 * and why we unlock later
+		 */
+		if (i != 0)
+			unlock_page(p);
 	}
 	if (uptodate)
 		set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
@@ -3216,9 +3233,26 @@ struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
 	atomic_inc(&eb->refs);
 	spin_unlock(&tree->buffer_lock);
 	radix_tree_preload_end();
+
+	/*
+	 * there is a race where release page may have
+	 * tried to find this extent buffer in the radix
+	 * but failed.  It will tell the VM it is safe to
+	 * reclaim the, and it will clear the page private bit.
+	 * We must make sure to set the page private bit properly
+	 * after the extent buffer is in the radix tree so
+	 * it doesn't get lost
+	 */
+	set_page_extent_mapped(eb->first_page);
+	set_page_extent_head(eb->first_page, eb->len);
+	if (!page0)
+		unlock_page(eb->first_page);
 	return eb;
 
 free_eb:
+	if (eb->first_page && !page0)
+		unlock_page(eb->first_page);
+
 	if (!atomic_dec_and_test(&eb->refs))
 		return exists;
 	btrfs_release_extent_buffer(eb);
@@ -3269,10 +3303,11 @@ int clear_extent_buffer_dirty(struct extent_io_tree *tree,
 			continue;
 
 		lock_page(page);
+		WARN_ON(!PagePrivate(page));
+
+		set_page_extent_mapped(page);
 		if (i == 0)
 			set_page_extent_head(page, eb->len);
-		else
-			set_page_private(page, EXTENT_PAGE_PRIVATE);
 
 		clear_page_dirty_for_io(page);
 		spin_lock_irq(&page->mapping->tree_lock);
@@ -3462,6 +3497,13 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
 
 	for (i = start_i; i < num_pages; i++) {
 		page = extent_buffer_page(eb, i);
+
+		WARN_ON(!PagePrivate(page));
+
+		set_page_extent_mapped(page);
+		if (i == 0)
+			set_page_extent_head(page, eb->len);
+
 		if (inc_all_pages)
 			page_cache_get(page);
 		if (!PageUptodate(page)) {
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index b0e1fce1253..2b6c12e983b 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -51,8 +51,8 @@ struct extent_map *alloc_extent_map(gfp_t mask)
 {
 	struct extent_map *em;
 	em = kmem_cache_alloc(extent_map_cache, mask);
-	if (!em || IS_ERR(em))
-		return em;
+	if (!em)
+		return NULL;
 	em->in_tree = 0;
 	em->flags = 0;
 	em->compress_type = BTRFS_COMPRESS_NONE;
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index a562a250ae7..4f19a3e1bf3 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -536,6 +536,8 @@ int btrfs_del_csums(struct btrfs_trans_handle *trans,
 	root = root->fs_info->csum_root;
 
 	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
 
 	while (1) {
 		key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
@@ -548,7 +550,10 @@ int btrfs_del_csums(struct btrfs_trans_handle *trans,
 			if (path->slots[0] == 0)
 				goto out;
 			path->slots[0]--;
+		} else if (ret < 0) {
+			goto out;
 		}
+
 		leaf = path->nodes[0];
 		btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
 
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index c800d58f301..7084140d594 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -186,6 +186,7 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
 			split = alloc_extent_map(GFP_NOFS);
 		if (!split2)
 			split2 = alloc_extent_map(GFP_NOFS);
+		BUG_ON(!split || !split2);
 
 		write_lock(&em_tree->lock);
 		em = lookup_extent_mapping(em_tree, start, len);
@@ -793,8 +794,12 @@ again:
 	for (i = 0; i < num_pages; i++) {
 		pages[i] = grab_cache_page(inode->i_mapping, index + i);
 		if (!pages[i]) {
-			err = -ENOMEM;
-			BUG_ON(1);
+			int c;
+			for (c = i - 1; c >= 0; c--) {
+				unlock_page(pages[c]);
+				page_cache_release(pages[c]);
+			}
+			return -ENOMEM;
 		}
 		wait_on_page_writeback(pages[i]);
 	}
@@ -946,6 +951,10 @@ static ssize_t btrfs_file_aio_write(struct kiocb *iocb,
 		     PAGE_CACHE_SIZE, PAGE_CACHE_SIZE /
 		     (sizeof(struct page *)));
 	pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL);
+	if (!pages) {
+		ret = -ENOMEM;
+		goto out;
+	}
 
 	/* generic_write_checks can change our pos */
 	start_pos = pos;
@@ -984,8 +993,8 @@ static ssize_t btrfs_file_aio_write(struct kiocb *iocb,
 		size_t write_bytes = min(iov_iter_count(&i),
 					 nrptrs * (size_t)PAGE_CACHE_SIZE -
 					 offset);
-		size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >>
-					PAGE_CACHE_SHIFT;
+		size_t num_pages = (write_bytes + offset +
+				    PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
 
 		WARN_ON(num_pages > nrptrs);
 		memset(pages, 0, sizeof(struct page *) * nrptrs);
@@ -1015,8 +1024,8 @@ static ssize_t btrfs_file_aio_write(struct kiocb *iocb,
 
 		copied = btrfs_copy_from_user(pos, num_pages,
 					   write_bytes, pages, &i);
-		dirty_pages = (copied + PAGE_CACHE_SIZE - 1) >>
-					PAGE_CACHE_SHIFT;
+		dirty_pages = (copied + offset + PAGE_CACHE_SIZE - 1) >>
+				PAGE_CACHE_SHIFT;
 
 		if (num_pages > dirty_pages) {
 			if (copied > 0)
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 60d68426695..a0390657451 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -987,11 +987,18 @@ tree_search_offset(struct btrfs_block_group_cache *block_group,
 	return entry;
 }
 
-static void unlink_free_space(struct btrfs_block_group_cache *block_group,
-			      struct btrfs_free_space *info)
+static inline void
+__unlink_free_space(struct btrfs_block_group_cache *block_group,
+		    struct btrfs_free_space *info)
 {
 	rb_erase(&info->offset_index, &block_group->free_space_offset);
 	block_group->free_extents--;
+}
+
+static void unlink_free_space(struct btrfs_block_group_cache *block_group,
+			      struct btrfs_free_space *info)
+{
+	__unlink_free_space(block_group, info);
 	block_group->free_space -= info->bytes;
 }
 
@@ -1016,14 +1023,18 @@ static void recalculate_thresholds(struct btrfs_block_group_cache *block_group)
 	u64 max_bytes;
 	u64 bitmap_bytes;
 	u64 extent_bytes;
+	u64 size = block_group->key.offset;
 
 	/*
 	 * The goal is to keep the total amount of memory used per 1gb of space
 	 * at or below 32k, so we need to adjust how much memory we allow to be
 	 * used by extent based free space tracking
 	 */
-	max_bytes = MAX_CACHE_BYTES_PER_GIG *
-		(div64_u64(block_group->key.offset, 1024 * 1024 * 1024));
+	if (size < 1024 * 1024 * 1024)
+		max_bytes = MAX_CACHE_BYTES_PER_GIG;
+	else
+		max_bytes = MAX_CACHE_BYTES_PER_GIG *
+			div64_u64(size, 1024 * 1024 * 1024);
 
 	/*
 	 * we want to account for 1 more bitmap than what we have so we can make
@@ -1171,6 +1182,16 @@ static void add_new_bitmap(struct btrfs_block_group_cache *block_group,
 	recalculate_thresholds(block_group);
 }
 
+static void free_bitmap(struct btrfs_block_group_cache *block_group,
+			struct btrfs_free_space *bitmap_info)
+{
+	unlink_free_space(block_group, bitmap_info);
+	kfree(bitmap_info->bitmap);
+	kfree(bitmap_info);
+	block_group->total_bitmaps--;
+	recalculate_thresholds(block_group);
+}
+
 static noinline int remove_from_bitmap(struct btrfs_block_group_cache *block_group,
 			      struct btrfs_free_space *bitmap_info,
 			      u64 *offset, u64 *bytes)
@@ -1195,6 +1216,7 @@ again:
 	 */
 	search_start = *offset;
 	search_bytes = *bytes;
+	search_bytes = min(search_bytes, end - search_start + 1);
 	ret = search_bitmap(block_group, bitmap_info, &search_start,
 			    &search_bytes);
 	BUG_ON(ret < 0 || search_start != *offset);
@@ -1211,13 +1233,8 @@ again:
 
 	if (*bytes) {
 		struct rb_node *next = rb_next(&bitmap_info->offset_index);
-		if (!bitmap_info->bytes) {
-			unlink_free_space(block_group, bitmap_info);
-			kfree(bitmap_info->bitmap);
-			kfree(bitmap_info);
-			block_group->total_bitmaps--;
-			recalculate_thresholds(block_group);
-		}
+		if (!bitmap_info->bytes)
+			free_bitmap(block_group, bitmap_info);
 
 		/*
 		 * no entry after this bitmap, but we still have bytes to
@@ -1250,13 +1267,8 @@ again:
 			return -EAGAIN;
 
 		goto again;
-	} else if (!bitmap_info->bytes) {
-		unlink_free_space(block_group, bitmap_info);
-		kfree(bitmap_info->bitmap);
-		kfree(bitmap_info);
-		block_group->total_bitmaps--;
-		recalculate_thresholds(block_group);
-	}
+	} else if (!bitmap_info->bytes)
+		free_bitmap(block_group, bitmap_info);
 
 	return 0;
 }
@@ -1359,22 +1371,14 @@ out:
 	return ret;
 }
 
-int btrfs_add_free_space(struct btrfs_block_group_cache *block_group,
-			 u64 offset, u64 bytes)
+bool try_merge_free_space(struct btrfs_block_group_cache *block_group,
+			  struct btrfs_free_space *info, bool update_stat)
 {
-	struct btrfs_free_space *right_info = NULL;
-	struct btrfs_free_space *left_info = NULL;
-	struct btrfs_free_space *info = NULL;
-	int ret = 0;
-
-	info = kzalloc(sizeof(struct btrfs_free_space), GFP_NOFS);
-	if (!info)
-		return -ENOMEM;
-
-	info->offset = offset;
-	info->bytes = bytes;
-
-	spin_lock(&block_group->tree_lock);
+	struct btrfs_free_space *left_info;
+	struct btrfs_free_space *right_info;
+	bool merged = false;
+	u64 offset = info->offset;
+	u64 bytes = info->bytes;
 
 	/*
 	 * first we want to see if there is free space adjacent to the range we
@@ -1388,37 +1392,62 @@ int btrfs_add_free_space(struct btrfs_block_group_cache *block_group,
 	else
 		left_info = tree_search_offset(block_group, offset - 1, 0, 0);
 
-	/*
-	 * If there was no extent directly to the left or right of this new
-	 * extent then we know we're going to have to allocate a new extent, so
-	 * before we do that see if we need to drop this into a bitmap
-	 */
-	if ((!left_info || left_info->bitmap) &&
-	    (!right_info || right_info->bitmap)) {
-		ret = insert_into_bitmap(block_group, info);
-
-		if (ret < 0) {
-			goto out;
-		} else if (ret) {
-			ret = 0;
-			goto out;
-		}
-	}
-
 	if (right_info && !right_info->bitmap) {
-		unlink_free_space(block_group, right_info);
+		if (update_stat)
+			unlink_free_space(block_group, right_info);
+		else
+			__unlink_free_space(block_group, right_info);
 		info->bytes += right_info->bytes;
 		kfree(right_info);
+		merged = true;
 	}
 
 	if (left_info && !left_info->bitmap &&
 	    left_info->offset + left_info->bytes == offset) {
-		unlink_free_space(block_group, left_info);
+		if (update_stat)
+			unlink_free_space(block_group, left_info);
+		else
+			__unlink_free_space(block_group, left_info);
 		info->offset = left_info->offset;
 		info->bytes += left_info->bytes;
 		kfree(left_info);
+		merged = true;
 	}
 
+	return merged;
+}
+
+int btrfs_add_free_space(struct btrfs_block_group_cache *block_group,
+			 u64 offset, u64 bytes)
+{
+	struct btrfs_free_space *info;
+	int ret = 0;
+
+	info = kzalloc(sizeof(struct btrfs_free_space), GFP_NOFS);
+	if (!info)
+		return -ENOMEM;
+
+	info->offset = offset;
+	info->bytes = bytes;
+
+	spin_lock(&block_group->tree_lock);
+
+	if (try_merge_free_space(block_group, info, true))
+		goto link;
+
+	/*
+	 * There was no extent directly to the left or right of this new
+	 * extent then we know we're going to have to allocate a new extent, so
+	 * before we do that see if we need to drop this into a bitmap
+	 */
+	ret = insert_into_bitmap(block_group, info);
+	if (ret < 0) {
+		goto out;
+	} else if (ret) {
+		ret = 0;
+		goto out;
+	}
+link:
 	ret = link_free_space(block_group, info);
 	if (ret)
 		kfree(info);
@@ -1621,6 +1650,7 @@ __btrfs_return_cluster_to_free_space(
 		node = rb_next(&entry->offset_index);
 		rb_erase(&entry->offset_index, &cluster->root);
 		BUG_ON(entry->bitmap);
+		try_merge_free_space(block_group, entry, false);
 		tree_insert_offset(&block_group->free_space_offset,
 				   entry->offset, &entry->offset_index, 0);
 	}
@@ -1685,13 +1715,8 @@ u64 btrfs_find_space_for_alloc(struct btrfs_block_group_cache *block_group,
 	ret = offset;
 	if (entry->bitmap) {
 		bitmap_clear_bits(block_group, entry, offset, bytes);
-		if (!entry->bytes) {
-			unlink_free_space(block_group, entry);
-			kfree(entry->bitmap);
-			kfree(entry);
-			block_group->total_bitmaps--;
-			recalculate_thresholds(block_group);
-		}
+		if (!entry->bytes)
+			free_bitmap(block_group, entry);
 	} else {
 		unlink_free_space(block_group, entry);
 		entry->offset += bytes;
@@ -1789,6 +1814,8 @@ static u64 btrfs_alloc_from_bitmap(struct btrfs_block_group_cache *block_group,
 
 	ret = search_start;
 	bitmap_clear_bits(block_group, entry, ret, bytes);
+	if (entry->bytes == 0)
+		free_bitmap(block_group, entry);
 out:
 	spin_unlock(&cluster->lock);
 	spin_unlock(&block_group->tree_lock);
@@ -1842,15 +1869,26 @@ u64 btrfs_alloc_from_cluster(struct btrfs_block_group_cache *block_group,
 		entry->offset += bytes;
 		entry->bytes -= bytes;
 
-		if (entry->bytes == 0) {
+		if (entry->bytes == 0)
 			rb_erase(&entry->offset_index, &cluster->root);
-			kfree(entry);
-		}
 		break;
 	}
 out:
 	spin_unlock(&cluster->lock);
 
+	if (!ret)
+		return 0;
+
+	spin_lock(&block_group->tree_lock);
+
+	block_group->free_space -= bytes;
+	if (entry->bytes == 0) {
+		block_group->free_extents--;
+		kfree(entry);
+	}
+
+	spin_unlock(&block_group->tree_lock);
+
 	return ret;
 }
 
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 160b55b3e13..fb9bd7832b6 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -416,7 +416,7 @@ again:
 	}
 	if (start == 0) {
 		trans = btrfs_join_transaction(root, 1);
-		BUG_ON(!trans);
+		BUG_ON(IS_ERR(trans));
 		btrfs_set_trans_block_group(trans, inode);
 		trans->block_rsv = &root->fs_info->delalloc_block_rsv;
 
@@ -612,6 +612,7 @@ retry:
 			    GFP_NOFS);
 
 		trans = btrfs_join_transaction(root, 1);
+		BUG_ON(IS_ERR(trans));
 		ret = btrfs_reserve_extent(trans, root,
 					   async_extent->compressed_size,
 					   async_extent->compressed_size,
@@ -643,6 +644,7 @@ retry:
 					async_extent->ram_size - 1, 0);
 
 		em = alloc_extent_map(GFP_NOFS);
+		BUG_ON(!em);
 		em->start = async_extent->start;
 		em->len = async_extent->ram_size;
 		em->orig_start = em->start;
@@ -771,7 +773,7 @@ static noinline int cow_file_range(struct inode *inode,
 
 	BUG_ON(root == root->fs_info->tree_root);
 	trans = btrfs_join_transaction(root, 1);
-	BUG_ON(!trans);
+	BUG_ON(IS_ERR(trans));
 	btrfs_set_trans_block_group(trans, inode);
 	trans->block_rsv = &root->fs_info->delalloc_block_rsv;
 
@@ -819,6 +821,7 @@ static noinline int cow_file_range(struct inode *inode,
 		BUG_ON(ret);
 
 		em = alloc_extent_map(GFP_NOFS);
+		BUG_ON(!em);
 		em->start = start;
 		em->orig_start = em->start;
 		ram_size = ins.offset;
@@ -1049,7 +1052,7 @@ static noinline int run_delalloc_nocow(struct inode *inode,
 	} else {
 		trans = btrfs_join_transaction(root, 1);
 	}
-	BUG_ON(!trans);
+	BUG_ON(IS_ERR(trans));
 
 	cow_start = (u64)-1;
 	cur_offset = start;
@@ -1168,6 +1171,7 @@ out_check:
 			struct extent_map_tree *em_tree;
 			em_tree = &BTRFS_I(inode)->extent_tree;
 			em = alloc_extent_map(GFP_NOFS);
+			BUG_ON(!em);
 			em->start = cur_offset;
 			em->orig_start = em->start;
 			em->len = num_bytes;
@@ -1557,6 +1561,7 @@ out:
 out_page:
 	unlock_page(page);
 	page_cache_release(page);
+	kfree(fixup);
 }
 
 /*
@@ -1703,7 +1708,7 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
 				trans = btrfs_join_transaction_nolock(root, 1);
 			else
 				trans = btrfs_join_transaction(root, 1);
-			BUG_ON(!trans);
+			BUG_ON(IS_ERR(trans));
 			btrfs_set_trans_block_group(trans, inode);
 			trans->block_rsv = &root->fs_info->delalloc_block_rsv;
 			ret = btrfs_update_inode(trans, root, inode);
@@ -1720,6 +1725,7 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
 		trans = btrfs_join_transaction_nolock(root, 1);
 	else
 		trans = btrfs_join_transaction(root, 1);
+	BUG_ON(IS_ERR(trans));
 	btrfs_set_trans_block_group(trans, inode);
 	trans->block_rsv = &root->fs_info->delalloc_block_rsv;
 
@@ -2354,6 +2360,7 @@ void btrfs_orphan_cleanup(struct btrfs_root *root)
 		 */
 		if (is_bad_inode(inode)) {
 			trans = btrfs_start_transaction(root, 0);
+			BUG_ON(IS_ERR(trans));
 			btrfs_orphan_del(trans, inode);
 			btrfs_end_transaction(trans, root);
 			iput(inode);
@@ -2381,6 +2388,7 @@ void btrfs_orphan_cleanup(struct btrfs_root *root)
 
 	if (root->orphan_block_rsv || root->orphan_item_inserted) {
 		trans = btrfs_join_transaction(root, 1);
+		BUG_ON(IS_ERR(trans));
 		btrfs_end_transaction(trans, root);
 	}
 
@@ -2641,7 +2649,7 @@ int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
 	path = btrfs_alloc_path();
 	if (!path) {
 		ret = -ENOMEM;
-		goto err;
+		goto out;
 	}
 
 	path->leave_spinning = 1;
@@ -2714,9 +2722,10 @@ static int check_path_shared(struct btrfs_root *root,
 	struct extent_buffer *eb;
 	int level;
 	u64 refs = 1;
-	int uninitialized_var(ret);
 
 	for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
+		int ret;
+
 		if (!path->nodes[level])
 			break;
 		eb = path->nodes[level];
@@ -2727,7 +2736,7 @@ static int check_path_shared(struct btrfs_root *root,
 		if (refs > 1)
 			return 1;
 	}
-	return ret; /* XXX callers? */
+	return 0;
 }
 
 /*
@@ -4134,7 +4143,7 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
 	}
 	srcu_read_unlock(&root->fs_info->subvol_srcu, index);
 
-	if (root != sub_root) {
+	if (!IS_ERR(inode) && root != sub_root) {
 		down_read(&root->fs_info->cleanup_work_sem);
 		if (!(inode->i_sb->s_flags & MS_RDONLY))
 			btrfs_orphan_cleanup(sub_root);
@@ -4347,6 +4356,8 @@ int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc)
 			trans = btrfs_join_transaction_nolock(root, 1);
 		else
 			trans = btrfs_join_transaction(root, 1);
+		if (IS_ERR(trans))
+			return PTR_ERR(trans);
 		btrfs_set_trans_block_group(trans, inode);
 		if (nolock)
 			ret = btrfs_end_transaction_nolock(trans, root);
@@ -4372,6 +4383,7 @@ void btrfs_dirty_inode(struct inode *inode)
 		return;
 
 	trans = btrfs_join_transaction(root, 1);
+	BUG_ON(IS_ERR(trans));
 	btrfs_set_trans_block_group(trans, inode);
 
 	ret = btrfs_update_inode(trans, root, inode);
@@ -5176,6 +5188,8 @@ again:
 				em = NULL;
 				btrfs_release_path(root, path);
 				trans = btrfs_join_transaction(root, 1);
+				if (IS_ERR(trans))
+					return ERR_CAST(trans);
 				goto again;
 			}
 			map = kmap(page);
@@ -5280,8 +5294,8 @@ static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
 	btrfs_drop_extent_cache(inode, start, start + len - 1, 0);
 
 	trans = btrfs_join_transaction(root, 0);
-	if (!trans)
-		return ERR_PTR(-ENOMEM);
+	if (IS_ERR(trans))
+		return ERR_CAST(trans);
 
 	trans->block_rsv = &root->fs_info->delalloc_block_rsv;
 
@@ -5505,7 +5519,7 @@ static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
 		 * while we look for nocow cross refs
 		 */
 		trans = btrfs_join_transaction(root, 0);
-		if (!trans)
+		if (IS_ERR(trans))
 			goto must_cow;
 
 		if (can_nocow_odirect(trans, inode, start, len) == 1) {
@@ -5640,7 +5654,7 @@ again:
 	BUG_ON(!ordered);
 
 	trans = btrfs_join_transaction(root, 1);
-	if (!trans) {
+	if (IS_ERR(trans)) {
 		err = -ENOMEM;
 		goto out;
 	}
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index a506a22b522..be2d4f6aaa5 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -203,7 +203,7 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
 
 
 	trans = btrfs_join_transaction(root, 1);
-	BUG_ON(!trans);
+	BUG_ON(IS_ERR(trans));
 
 	ret = btrfs_update_inode(trans, root, inode);
 	BUG_ON(ret);
@@ -907,6 +907,10 @@ static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
 
 	if (new_size > old_size) {
 		trans = btrfs_start_transaction(root, 0);
+		if (IS_ERR(trans)) {
+			ret = PTR_ERR(trans);
+			goto out_unlock;
+		}
 		ret = btrfs_grow_device(trans, device, new_size);
 		btrfs_commit_transaction(trans, root);
 	} else {
@@ -1898,7 +1902,10 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
 
 			memcpy(&new_key, &key, sizeof(new_key));
 			new_key.objectid = inode->i_ino;
-			new_key.offset = key.offset + destoff - off;
+			if (off <= key.offset)
+				new_key.offset = key.offset + destoff - off;
+			else
+				new_key.offset = destoff;
 
 			trans = btrfs_start_transaction(root, 1);
 			if (IS_ERR(trans)) {
@@ -2082,7 +2089,7 @@ static long btrfs_ioctl_trans_start(struct file *file)
 
 	ret = -ENOMEM;
 	trans = btrfs_start_ioctl_transaction(root, 0);
-	if (!trans)
+	if (IS_ERR(trans))
 		goto out_drop;
 
 	file->private_data = trans;
@@ -2138,9 +2145,9 @@ static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
 	path->leave_spinning = 1;
 
 	trans = btrfs_start_transaction(root, 1);
-	if (!trans) {
+	if (IS_ERR(trans)) {
 		btrfs_free_path(path);
-		return -ENOMEM;
+		return PTR_ERR(trans);
 	}
 
 	dir_id = btrfs_super_root_dir(&root->fs_info->super_copy);
@@ -2201,7 +2208,7 @@ long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
 	int num_types = 4;
 	int alloc_size;
 	int ret = 0;
-	int slot_count = 0;
+	u64 slot_count = 0;
 	int i, c;
 
 	if (copy_from_user(&space_args,
@@ -2240,7 +2247,7 @@ long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
 		goto out;
 	}
 
-	slot_count = min_t(int, space_args.space_slots, slot_count);
+	slot_count = min_t(u64, space_args.space_slots, slot_count);
 
 	alloc_size = sizeof(*dest) * slot_count;
 
@@ -2260,6 +2267,9 @@ long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
 	for (i = 0; i < num_types; i++) {
 		struct btrfs_space_info *tmp;
 
+		if (!slot_count)
+			break;
+
 		info = NULL;
 		rcu_read_lock();
 		list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
@@ -2281,7 +2291,10 @@ long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
 				memcpy(dest, &space, sizeof(space));
 				dest++;
 				space_args.total_spaces++;
+				slot_count--;
 			}
+			if (!slot_count)
+				break;
 		}
 		up_read(&info->groups_sem);
 	}
@@ -2334,6 +2347,8 @@ static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp
 	u64 transid;
 
 	trans = btrfs_start_transaction(root, 0);
+	if (IS_ERR(trans))
+		return PTR_ERR(trans);
 	transid = trans->transid;
 	btrfs_commit_transaction_async(trans, root, 0);
 
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 2b61e1ddcd9..083a5547737 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -141,7 +141,7 @@ static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree,
 					  u64 file_offset)
 {
 	struct rb_root *root = &tree->tree;
-	struct rb_node *prev;
+	struct rb_node *prev = NULL;
 	struct rb_node *ret;
 	struct btrfs_ordered_extent *entry;
 
diff --git a/fs/btrfs/print-tree.c b/fs/btrfs/print-tree.c
index 0d126be22b6..fb2605d998e 100644
--- a/fs/btrfs/print-tree.c
+++ b/fs/btrfs/print-tree.c
@@ -260,6 +260,7 @@ void btrfs_print_leaf(struct btrfs_root *root, struct extent_buffer *l)
 #else
 			BUG();
 #endif
+			break;
 		case BTRFS_BLOCK_GROUP_ITEM_KEY:
 			bi = btrfs_item_ptr(l, i,
 					    struct btrfs_block_group_item);
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 045c9c2b2d7..0825e4ed944 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -1157,6 +1157,7 @@ static int clone_backref_node(struct btrfs_trans_handle *trans,
 	new_node->bytenr = dest->node->start;
 	new_node->level = node->level;
 	new_node->lowest = node->lowest;
+	new_node->checked = 1;
 	new_node->root = dest;
 
 	if (!node->lowest) {
@@ -2028,6 +2029,7 @@ static noinline_for_stack int merge_reloc_root(struct reloc_control *rc,
 
 	while (1) {
 		trans = btrfs_start_transaction(root, 0);
+		BUG_ON(IS_ERR(trans));
 		trans->block_rsv = rc->block_rsv;
 
 		ret = btrfs_block_rsv_check(trans, root, rc->block_rsv,
@@ -2147,6 +2149,12 @@ again:
 	}
 
 	trans = btrfs_join_transaction(rc->extent_root, 1);
+	if (IS_ERR(trans)) {
+		if (!err)
+			btrfs_block_rsv_release(rc->extent_root,
+						rc->block_rsv, num_bytes);
+		return PTR_ERR(trans);
+	}
 
 	if (!err) {
 		if (num_bytes != rc->merging_rsv_size) {
@@ -3222,6 +3230,7 @@ truncate:
 	trans = btrfs_join_transaction(root, 0);
 	if (IS_ERR(trans)) {
 		btrfs_free_path(path);
+		ret = PTR_ERR(trans);
 		goto out;
 	}
 
@@ -3628,6 +3637,7 @@ int prepare_to_relocate(struct reloc_control *rc)
 	set_reloc_control(rc);
 
 	trans = btrfs_join_transaction(rc->extent_root, 1);
+	BUG_ON(IS_ERR(trans));
 	btrfs_commit_transaction(trans, rc->extent_root);
 	return 0;
 }
@@ -3657,6 +3667,7 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
 
 	while (1) {
 		trans = btrfs_start_transaction(rc->extent_root, 0);
+		BUG_ON(IS_ERR(trans));
 
 		if (update_backref_cache(trans, &rc->backref_cache)) {
 			btrfs_end_transaction(trans, rc->extent_root);
@@ -3804,7 +3815,10 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
 
 	/* get rid of pinned extents */
 	trans = btrfs_join_transaction(rc->extent_root, 1);
-	btrfs_commit_transaction(trans, rc->extent_root);
+	if (IS_ERR(trans))
+		err = PTR_ERR(trans);
+	else
+		btrfs_commit_transaction(trans, rc->extent_root);
 out_free:
 	btrfs_free_block_rsv(rc->extent_root, rc->block_rsv);
 	btrfs_free_path(path);
@@ -4022,6 +4036,7 @@ static noinline_for_stack int mark_garbage_root(struct btrfs_root *root)
 	int ret;
 
 	trans = btrfs_start_transaction(root->fs_info->tree_root, 0);
+	BUG_ON(IS_ERR(trans));
 
 	memset(&root->root_item.drop_progress, 0,
 		sizeof(root->root_item.drop_progress));
@@ -4125,6 +4140,11 @@ int btrfs_recover_relocation(struct btrfs_root *root)
 	set_reloc_control(rc);
 
 	trans = btrfs_join_transaction(rc->extent_root, 1);
+	if (IS_ERR(trans)) {
+		unset_reloc_control(rc);
+		err = PTR_ERR(trans);
+		goto out_free;
+	}
 
 	rc->merge_reloc_tree = 1;
 
@@ -4154,9 +4174,13 @@ int btrfs_recover_relocation(struct btrfs_root *root)
 	unset_reloc_control(rc);
 
 	trans = btrfs_join_transaction(rc->extent_root, 1);
-	btrfs_commit_transaction(trans, rc->extent_root);
-out:
+	if (IS_ERR(trans))
+		err = PTR_ERR(trans);
+	else
+		btrfs_commit_transaction(trans, rc->extent_root);
+out_free:
 	kfree(rc);
+out:
 	while (!list_empty(&reloc_roots)) {
 		reloc_root = list_entry(reloc_roots.next,
 					struct btrfs_root, root_list);
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index b2130c46fdb..a004008f7d2 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -383,7 +383,7 @@ static int btrfs_parse_early_options(const char *options, fmode_t flags,
 		struct btrfs_fs_devices **fs_devices)
 {
 	substring_t args[MAX_OPT_ARGS];
-	char *opts, *p;
+	char *opts, *orig, *p;
 	int error = 0;
 	int intarg;
 
@@ -397,6 +397,7 @@ static int btrfs_parse_early_options(const char *options, fmode_t flags,
 	opts = kstrdup(options, GFP_KERNEL);
 	if (!opts)
 		return -ENOMEM;
+	orig = opts;
 
 	while ((p = strsep(&opts, ",")) != NULL) {
 		int token;
@@ -432,7 +433,7 @@ static int btrfs_parse_early_options(const char *options, fmode_t flags,
 	}
 
  out_free_opts:
-	kfree(opts);
+	kfree(orig);
  out:
 	/*
 	 * If no subvolume name is specified we use the default one.  Allocate
@@ -623,6 +624,8 @@ int btrfs_sync_fs(struct super_block *sb, int wait)
 	btrfs_wait_ordered_extents(root, 0, 0);
 
 	trans = btrfs_start_transaction(root, 0);
+	if (IS_ERR(trans))
+		return PTR_ERR(trans);
 	ret = btrfs_commit_transaction(trans, root);
 	return ret;
 }
@@ -761,6 +764,8 @@ static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags,
 		}
 
 		btrfs_close_devices(fs_devices);
+		kfree(fs_info);
+		kfree(tree_root);
 	} else {
 		char b[BDEVNAME_SIZE];
 
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index bae5c7b8bbe..3d73c8d93bb 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -1161,6 +1161,11 @@ int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
 	INIT_DELAYED_WORK(&ac->work, do_async_commit);
 	ac->root = root;
 	ac->newtrans = btrfs_join_transaction(root, 0);
+	if (IS_ERR(ac->newtrans)) {
+		int err = PTR_ERR(ac->newtrans);
+		kfree(ac);
+		return err;
+	}
 
 	/* take transaction reference */
 	mutex_lock(&root->fs_info->trans_mutex);
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 054744ac571..a4bbb854dfd 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -338,6 +338,12 @@ static noinline int overwrite_item(struct btrfs_trans_handle *trans,
 		}
 		dst_copy = kmalloc(item_size, GFP_NOFS);
 		src_copy = kmalloc(item_size, GFP_NOFS);
+		if (!dst_copy || !src_copy) {
+			btrfs_release_path(root, path);
+			kfree(dst_copy);
+			kfree(src_copy);
+			return -ENOMEM;
+		}
 
 		read_extent_buffer(eb, src_copy, src_ptr, item_size);
 
@@ -665,6 +671,9 @@ static noinline int drop_one_dir_item(struct btrfs_trans_handle *trans,
 	btrfs_dir_item_key_to_cpu(leaf, di, &location);
 	name_len = btrfs_dir_name_len(leaf, di);
 	name = kmalloc(name_len, GFP_NOFS);
+	if (!name)
+		return -ENOMEM;
+
 	read_extent_buffer(leaf, name, (unsigned long)(di + 1), name_len);
 	btrfs_release_path(root, path);
 
@@ -744,6 +753,9 @@ static noinline int backref_in_log(struct btrfs_root *log,
 	int match = 0;
 
 	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
+
 	ret = btrfs_search_slot(NULL, log, key, path, 0, 0);
 	if (ret != 0)
 		goto out;
@@ -967,6 +979,8 @@ static noinline int fixup_inode_link_count(struct btrfs_trans_handle *trans,
 	key.offset = (u64)-1;
 
 	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
 
 	while (1) {
 		ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
@@ -1178,6 +1192,9 @@ static noinline int replay_one_name(struct btrfs_trans_handle *trans,
 
 	name_len = btrfs_dir_name_len(eb, di);
 	name = kmalloc(name_len, GFP_NOFS);
+	if (!name)
+		return -ENOMEM;
+
 	log_type = btrfs_dir_type(eb, di);
 	read_extent_buffer(eb, name, (unsigned long)(di + 1),
 		   name_len);
@@ -1692,6 +1709,8 @@ static noinline int walk_down_log_tree(struct btrfs_trans_handle *trans,
 		root_owner = btrfs_header_owner(parent);
 
 		next = btrfs_find_create_tree_block(root, bytenr, blocksize);
+		if (!next)
+			return -ENOMEM;
 
 		if (*level == 1) {
 			wc->process_func(root, next, wc, ptr_gen);
@@ -2032,6 +2051,7 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 		wait_log_commit(trans, log_root_tree,
 				log_root_tree->log_transid);
 		mutex_unlock(&log_root_tree->log_mutex);
+		ret = 0;
 		goto out;
 	}
 	atomic_set(&log_root_tree->log_commit[index2], 1);
@@ -2096,7 +2116,7 @@ out:
 	smp_mb();
 	if (waitqueue_active(&root->log_commit_wait[index1]))
 		wake_up(&root->log_commit_wait[index1]);
-	return 0;
+	return ret;
 }
 
 static void free_log_tree(struct btrfs_trans_handle *trans,
@@ -2194,6 +2214,9 @@ int btrfs_del_dir_entries_in_log(struct btrfs_trans_handle *trans,
 
 	log = root->log_root;
 	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
+
 	di = btrfs_lookup_dir_item(trans, log, path, dir->i_ino,
 				   name, name_len, -1);
 	if (IS_ERR(di)) {
@@ -2594,6 +2617,9 @@ static noinline int copy_items(struct btrfs_trans_handle *trans,
 
 	ins_data = kmalloc(nr * sizeof(struct btrfs_key) +
 			   nr * sizeof(u32), GFP_NOFS);
+	if (!ins_data)
+		return -ENOMEM;
+
 	ins_sizes = (u32 *)ins_data;
 	ins_keys = (struct btrfs_key *)(ins_data + nr * sizeof(u32));
 
@@ -2725,7 +2751,13 @@ static int btrfs_log_inode(struct btrfs_trans_handle *trans,
 	log = root->log_root;
 
 	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
 	dst_path = btrfs_alloc_path();
+	if (!dst_path) {
+		btrfs_free_path(path);
+		return -ENOMEM;
+	}
 
 	min_key.objectid = inode->i_ino;
 	min_key.type = BTRFS_INODE_ITEM_KEY;
@@ -3080,6 +3112,7 @@ int btrfs_recover_log_trees(struct btrfs_root *log_root_tree)
 	BUG_ON(!path);
 
 	trans = btrfs_start_transaction(fs_info->tree_root, 0);
+	BUG_ON(IS_ERR(trans));
 
 	wc.trans = trans;
 	wc.pin = 1;
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index d158530233b..af7dbca1527 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1213,6 +1213,10 @@ static int btrfs_rm_dev_item(struct btrfs_root *root,
 		return -ENOMEM;
 
 	trans = btrfs_start_transaction(root, 0);
+	if (IS_ERR(trans)) {
+		btrfs_free_path(path);
+		return PTR_ERR(trans);
+	}
 	key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
 	key.type = BTRFS_DEV_ITEM_KEY;
 	key.offset = device->devid;
@@ -1601,11 +1605,19 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
 
 	ret = find_next_devid(root, &device->devid);
 	if (ret) {
+		kfree(device->name);
 		kfree(device);
 		goto error;
 	}
 
 	trans = btrfs_start_transaction(root, 0);
+	if (IS_ERR(trans)) {
+		kfree(device->name);
+		kfree(device);
+		ret = PTR_ERR(trans);
+		goto error;
+	}
+
 	lock_chunks(root);
 
 	device->writeable = 1;
@@ -1873,7 +1885,7 @@ static int btrfs_relocate_chunk(struct btrfs_root *root,
 		return ret;
 
 	trans = btrfs_start_transaction(root, 0);
-	BUG_ON(!trans);
+	BUG_ON(IS_ERR(trans));
 
 	lock_chunks(root);
 
@@ -2047,7 +2059,7 @@ int btrfs_balance(struct btrfs_root *dev_root)
 		BUG_ON(ret);
 
 		trans = btrfs_start_transaction(dev_root, 0);
-		BUG_ON(!trans);
+		BUG_ON(IS_ERR(trans));
 
 		ret = btrfs_grow_device(trans, device, old_size);
 		BUG_ON(ret);
@@ -2213,6 +2225,11 @@ again:
 
 	/* Shrinking succeeded, else we would be at "done". */
 	trans = btrfs_start_transaction(root, 0);
+	if (IS_ERR(trans)) {
+		ret = PTR_ERR(trans);
+		goto done;
+	}
+
 	lock_chunks(root);
 
 	device->disk_total_bytes = new_size;