Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable

* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (33 commits)
  Btrfs: Fix page count calculation
  btrfs: Drop __exit attribute on btrfs_exit_compress
  btrfs: cleanup error handling in btrfs_unlink_inode()
  Btrfs: exclude super blocks when we read in block groups
  Btrfs: make sure search_bitmap finds something in remove_from_bitmap
  btrfs: fix return value check of btrfs_start_transaction()
  btrfs: checking NULL or not in some functions
  Btrfs: avoid uninit variable warnings in ordered-data.c
  Btrfs: catch errors from btrfs_sync_log
  Btrfs: make shrink_delalloc a little friendlier
  Btrfs: handle no memory properly in prepare_pages
  Btrfs: do error checking in btrfs_del_csums
  Btrfs: use the global block reserve if we cannot reserve space
  Btrfs: do not release more reserved bytes to the global_block_rsv than we need
  Btrfs: fix check_path_shared so it returns the right value
  btrfs: check return value of btrfs_start_ioctl_transaction() properly
  btrfs: fix return value check of btrfs_join_transaction()
  fs/btrfs/inode.c: Add missing IS_ERR test
  btrfs: fix missing break in switch phrase
  btrfs: fix several uncheck memory allocations
  ...

18 files changed, 371 insertions, 116 deletions

diff --git a/fs/btrfs/acl.c b/fs/btrfs/acl.c
index 15b5ca2a2606..9c949348510b 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 f745287fbf2e..4d2110eafe29 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 b531c36455d8..fdce8799b98d 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1550,6 +1550,7 @@ 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 +2454,14 @@ 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 +2559,8 @@ 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 9786963b07e5..ff27d7a477b2 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 b55269340cec..4e7e012ad667 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;
@@ -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 2e993cf1766e..5e76a474cb7e 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;
@@ -2126,7 +2128,7 @@ 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;
 }
 
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index a562a250ae77..4f19a3e1bf32 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 c800d58f3013..c1d3a818731a 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -793,8 +793,12 @@ 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 +950,10 @@ 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 +992,8 @@ 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 +1023,8 @@ 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 60d684266959..a0390657451b 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 160b55b3e132..bcc461a9695f 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,
@@ -771,7 +772,7 @@ 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;
 
@@ -1049,7 +1050,7 @@ 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;
@@ -1557,6 +1558,7 @@ out:
 out_page:
         unlock_page(page);
         page_cache_release(page);
+        kfree(fixup);
 }
 
 /*
@@ -1703,7 +1705,7 @@ 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 +1722,7 @@ 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 +2357,7 @@ 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 +2385,7 @@ 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 +2646,7 @@ 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 +2719,10 @@ 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 +2733,7 @@ static int check_path_shared(struct btrfs_root *root,
                 if (refs > 1)
                         return 1;
         }
-        return ret; /* XXX callers? */
+        return 0;
 }
 
 /*
@@ -4134,7 +4140,7 @@ 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 +4353,8 @@ 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 +4380,7 @@ 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 +5185,8 @@ 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 +5291,8 @@ 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 +5516,7 @@ 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 +5651,7 @@ 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 a506a22b522a..02d224e8c83f 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);
@@ -2334,6 +2341,8 @@ 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 2b61e1ddcd99..083a55477375 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 0d126be22b63..fb2605d998e9 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 045c9c2b2d7e..1f5556acb530 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -2028,6 +2028,7 @@ 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 +2148,12 @@ 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 +3229,7 @@ truncate:
         trans = btrfs_join_transaction(root, 0);
         if (IS_ERR(trans)) {
                 btrfs_free_path(path);
+                ret = PTR_ERR(trans);
                 goto out;
         }
 
@@ -3628,6 +3636,7 @@ 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 +3666,7 @@ 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 +3814,10 @@ 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 +4035,7 @@ 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 +4139,11 @@ 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 +4173,13 @@ 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 b2130c46fdb5..a004008f7d28 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 bae5c7b8bbe2..3d73c8d93bbb 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 054744ac5719..a4bbb854dfd2 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 d158530233b7..2636a051e4b2 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;
@@ -1606,6 +1610,12 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
         }
 
         trans = btrfs_start_transaction(root, 0);
+        if (IS_ERR(trans)) {
+                kfree(device);
+                ret = PTR_ERR(trans);
+                goto error;
+        }
+
         lock_chunks(root);
 
         device->writeable = 1;
@@ -1873,7 +1883,7 @@ 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 +2057,7 @@ 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 +2223,11 @@ 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;