Btrfs: fix tree mod logging
authorFilipe David Borba Manana <fdmanana@gmail.com>
Fri, 20 Dec 2013 15:17:46 +0000 (15:17 +0000)
committerChris Mason <clm@fb.com>
Tue, 28 Jan 2014 21:20:04 +0000 (13:20 -0800)
While running the test btrfs/004 from xfstests in a loop, it failed
about 1 time out of 20 runs in my desktop. The failure happened in
the backref walking part of the test, and the test's error message was
like this:

  btrfs/004 93s ... [failed, exit status 1] - output mismatch (see /home/fdmanana/git/hub/xfstests_2/results//btrfs/004.out.bad)
      --- tests/btrfs/004.out 2013-11-26 18:25:29.263333714 +0000
      +++ /home/fdmanana/git/hub/xfstests_2/results//btrfs/004.out.bad 2013-12-10 15:25:10.327518516 +0000
      @@ -1,3 +1,8 @@
       QA output created by 004
       *** test backref walking
      -*** done
      +unexpected output from
      + /home/fdmanana/git/hub/btrfs-progs/btrfs inspect-internal logical-resolve -P 141512704 /home/fdmanana/btrfs-tests/scratch_1
      +expected inum: 405, expected address: 454656, file: /home/fdmanana/btrfs-tests/scratch_1/snap1/p0/d6/d3d/d156/fce, got:
      +
       ...
       (Run 'diff -u tests/btrfs/004.out /home/fdmanana/git/hub/xfstests_2/results//btrfs/004.out.bad' to see the entire diff)
  Ran: btrfs/004
  Failures: btrfs/004
  Failed 1 of 1 tests

But immediately after the test finished, the btrfs inspect-internal command
returned the expected output:

  $ btrfs inspect-internal logical-resolve -P 141512704 /home/fdmanana/btrfs-tests/scratch_1
  inode 405 offset 454656 root 258
  inode 405 offset 454656 root 5

It turned out this was because the btrfs_search_old_slot() calls performed
during backref walking (backref.c:__resolve_indirect_ref) were not finding
anything. The reason for this turned out to be that the tree mod logging
code was not logging some node multi-step operations atomically, therefore
btrfs_search_old_slot() callers iterated often over an incomplete tree that
wasn't fully consistent with any tree state from the past. Besides missing
items, this often (but not always) resulted in -EIO errors during old slot
searches, reported in dmesg like this:

[ 4299.933936] ------------[ cut here ]------------
[ 4299.933949] WARNING: CPU: 0 PID: 23190 at fs/btrfs/ctree.c:1343 btrfs_search_old_slot+0x57b/0xab0 [btrfs]()
[ 4299.933950] Modules linked in: btrfs raid6_pq xor pci_stub vboxpci(O) vboxnetadp(O) vboxnetflt(O) vboxdrv(O) bnep rfcomm bluetooth parport_pc ppdev binfmt_misc joydev snd_hda_codec_h
[ 4299.933977] CPU: 0 PID: 23190 Comm: btrfs Tainted: G        W  O 3.12.0-fdm-btrfs-next-16+ #70
[ 4299.933978] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./Z77 Pro4, BIOS P1.50 09/04/2012
[ 4299.933979]  000000000000053f ffff8806f3fd98f8 ffffffff8176d284 0000000000000007
[ 4299.933982]  0000000000000000 ffff8806f3fd9938 ffffffff8104a81c ffff880659c64b70
[ 4299.933984]  ffff880659c643d0 ffff8806599233d8 ffff880701e2e938 0000160000000000
[ 4299.933987] Call Trace:
[ 4299.933991]  [<ffffffff8176d284>] dump_stack+0x55/0x76
[ 4299.933994]  [<ffffffff8104a81c>] warn_slowpath_common+0x8c/0xc0
[ 4299.933997]  [<ffffffff8104a86a>] warn_slowpath_null+0x1a/0x20
[ 4299.934003]  [<ffffffffa065d3bb>] btrfs_search_old_slot+0x57b/0xab0 [btrfs]
[ 4299.934005]  [<ffffffff81775f3b>] ? _raw_read_unlock+0x2b/0x50
[ 4299.934010]  [<ffffffffa0655001>] ? __tree_mod_log_search+0x81/0xc0 [btrfs]
[ 4299.934019]  [<ffffffffa06dd9b0>] __resolve_indirect_refs+0x130/0x5f0 [btrfs]
[ 4299.934027]  [<ffffffffa06a21f1>] ? free_extent_buffer+0x61/0xc0 [btrfs]
[ 4299.934034]  [<ffffffffa06de39c>] find_parent_nodes+0x1fc/0xe40 [btrfs]
[ 4299.934042]  [<ffffffffa06b13e0>] ? defrag_lookup_extent+0xe0/0xe0 [btrfs]
[ 4299.934048]  [<ffffffffa06b13e0>] ? defrag_lookup_extent+0xe0/0xe0 [btrfs]
[ 4299.934056]  [<ffffffffa06df980>] iterate_extent_inodes+0xe0/0x250 [btrfs]
[ 4299.934058]  [<ffffffff817762db>] ? _raw_spin_unlock+0x2b/0x50
[ 4299.934065]  [<ffffffffa06dfb82>] iterate_inodes_from_logical+0x92/0xb0 [btrfs]
[ 4299.934071]  [<ffffffffa06b13e0>] ? defrag_lookup_extent+0xe0/0xe0 [btrfs]
[ 4299.934078]  [<ffffffffa06b7015>] btrfs_ioctl+0xf65/0x1f60 [btrfs]
[ 4299.934080]  [<ffffffff811658b8>] ? handle_mm_fault+0x278/0xb00
[ 4299.934083]  [<ffffffff81075563>] ? up_read+0x23/0x40
[ 4299.934085]  [<ffffffff8177a41c>] ? __do_page_fault+0x20c/0x5a0
[ 4299.934088]  [<ffffffff811b2946>] do_vfs_ioctl+0x96/0x570
[ 4299.934090]  [<ffffffff81776e23>] ? error_sti+0x5/0x6
[ 4299.934093]  [<ffffffff810b71e8>] ? trace_hardirqs_off_caller+0x28/0xd0
[ 4299.934096]  [<ffffffff81776a09>] ? retint_swapgs+0xe/0x13
[ 4299.934098]  [<ffffffff811b2eb1>] SyS_ioctl+0x91/0xb0
[ 4299.934100]  [<ffffffff813eecde>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[ 4299.934102]  [<ffffffff8177ef12>] system_call_fastpath+0x16/0x1b
[ 4299.934102]  [<ffffffff8177ef12>] system_call_fastpath+0x16/0x1b
[ 4299.934104] ---[ end trace 48f0cfc902491414 ]---
[ 4299.934378] btrfs bad fsid on block 0

These tree mod log operations that must be performed atomically, tree_mod_log_free_eb,
tree_mod_log_eb_copy, tree_mod_log_insert_root and tree_mod_log_insert_move, used to
be performed atomically before the following commit:

  c8cc6341653721b54760480b0d0d9b5f09b46741
  (Btrfs: stop using GFP_ATOMIC for the tree mod log allocations)

That change removed the atomicity of such operations. This patch restores the
atomicity while still not doing the GFP_ATOMIC allocations of tree_mod_elem
structures, so it has to do the allocations using GFP_NOFS before acquiring
the mod log lock.

This issue has been experienced by several users recently, such as for example:

  http://www.spinics.net/lists/linux-btrfs/msg28574.html

After running the btrfs/004 test for 679 consecutive iterations with this
patch applied, I didn't ran into the issue anymore.

Cc: stable@vger.kernel.org
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
fs/btrfs/ctree.c

index 59664f6cbc4e9830ea0b01c142a872656286cf94..7d88d8543aa1e5c29fc2f55553ac65352f7fcb8e 100644 (file)
@@ -39,7 +39,7 @@ static int balance_node_right(struct btrfs_trans_handle *trans,
                              struct extent_buffer *src_buf);
 static void del_ptr(struct btrfs_root *root, struct btrfs_path *path,
                    int level, int slot);
-static void tree_mod_log_free_eb(struct btrfs_fs_info *fs_info,
+static int tree_mod_log_free_eb(struct btrfs_fs_info *fs_info,
                                 struct extent_buffer *eb);
 
 struct btrfs_path *btrfs_alloc_path(void)
@@ -474,6 +474,8 @@ void btrfs_put_tree_mod_seq(struct btrfs_fs_info *fs_info,
  * the index is the shifted logical of the *new* root node for root replace
  * operations, or the shifted logical of the affected block for all other
  * operations.
+ *
+ * Note: must be called with write lock (tree_mod_log_write_lock).
  */
 static noinline int
 __tree_mod_log_insert(struct btrfs_fs_info *fs_info, struct tree_mod_elem *tm)
@@ -482,24 +484,9 @@ __tree_mod_log_insert(struct btrfs_fs_info *fs_info, struct tree_mod_elem *tm)
        struct rb_node **new;
        struct rb_node *parent = NULL;
        struct tree_mod_elem *cur;
-       int ret = 0;
 
        BUG_ON(!tm);
 
-       tree_mod_log_write_lock(fs_info);
-       if (list_empty(&fs_info->tree_mod_seq_list)) {
-               tree_mod_log_write_unlock(fs_info);
-               /*
-                * Ok we no longer care about logging modifications, free up tm
-                * and return 0.  Any callers shouldn't be using tm after
-                * calling tree_mod_log_insert, but if they do we can just
-                * change this to return a special error code to let the callers
-                * do their own thing.
-                */
-               kfree(tm);
-               return 0;
-       }
-
        spin_lock(&fs_info->tree_mod_seq_lock);
        tm->seq = btrfs_inc_tree_mod_seq_minor(fs_info);
        spin_unlock(&fs_info->tree_mod_seq_lock);
@@ -517,18 +504,13 @@ __tree_mod_log_insert(struct btrfs_fs_info *fs_info, struct tree_mod_elem *tm)
                        new = &((*new)->rb_left);
                else if (cur->seq > tm->seq)
                        new = &((*new)->rb_right);
-               else {
-                       ret = -EEXIST;
-                       kfree(tm);
-                       goto out;
-               }
+               else
+                       return -EEXIST;
        }
 
        rb_link_node(&tm->node, parent, new);
        rb_insert_color(&tm->node, tm_root);
-out:
-       tree_mod_log_write_unlock(fs_info);
-       return ret;
+       return 0;
 }
 
 /*
@@ -544,19 +526,38 @@ static inline int tree_mod_dont_log(struct btrfs_fs_info *fs_info,
                return 1;
        if (eb && btrfs_header_level(eb) == 0)
                return 1;
+
+       tree_mod_log_write_lock(fs_info);
+       if (list_empty(&(fs_info)->tree_mod_seq_list)) {
+               tree_mod_log_write_unlock(fs_info);
+               return 1;
+       }
+
        return 0;
 }
 
-static inline int
-__tree_mod_log_insert_key(struct btrfs_fs_info *fs_info,
-                         struct extent_buffer *eb, int slot,
-                         enum mod_log_op op, gfp_t flags)
+/* Similar to tree_mod_dont_log, but doesn't acquire any locks. */
+static inline int tree_mod_need_log(const struct btrfs_fs_info *fs_info,
+                                   struct extent_buffer *eb)
+{
+       smp_mb();
+       if (list_empty(&(fs_info)->tree_mod_seq_list))
+               return 0;
+       if (eb && btrfs_header_level(eb) == 0)
+               return 0;
+
+       return 1;
+}
+
+static struct tree_mod_elem *
+alloc_tree_mod_elem(struct extent_buffer *eb, int slot,
+                   enum mod_log_op op, gfp_t flags)
 {
        struct tree_mod_elem *tm;
 
        tm = kzalloc(sizeof(*tm), flags);
        if (!tm)
-               return -ENOMEM;
+               return NULL;
 
        tm->index = eb->start >> PAGE_CACHE_SHIFT;
        if (op != MOD_LOG_KEY_ADD) {
@@ -566,8 +567,9 @@ __tree_mod_log_insert_key(struct btrfs_fs_info *fs_info,
        tm->op = op;
        tm->slot = slot;
        tm->generation = btrfs_node_ptr_generation(eb, slot);
+       RB_CLEAR_NODE(&tm->node);
 
-       return __tree_mod_log_insert(fs_info, tm);
+       return tm;
 }
 
 static noinline int
@@ -575,10 +577,27 @@ tree_mod_log_insert_key(struct btrfs_fs_info *fs_info,
                        struct extent_buffer *eb, int slot,
                        enum mod_log_op op, gfp_t flags)
 {
-       if (tree_mod_dont_log(fs_info, eb))
+       struct tree_mod_elem *tm;
+       int ret;
+
+       if (!tree_mod_need_log(fs_info, eb))
+               return 0;
+
+       tm = alloc_tree_mod_elem(eb, slot, op, flags);
+       if (!tm)
+               return -ENOMEM;
+
+       if (tree_mod_dont_log(fs_info, eb)) {
+               kfree(tm);
                return 0;
+       }
+
+       ret = __tree_mod_log_insert(fs_info, tm);
+       tree_mod_log_write_unlock(fs_info);
+       if (ret)
+               kfree(tm);
 
-       return __tree_mod_log_insert_key(fs_info, eb, slot, op, flags);
+       return ret;
 }
 
 static noinline int
@@ -586,53 +605,95 @@ tree_mod_log_insert_move(struct btrfs_fs_info *fs_info,
                         struct extent_buffer *eb, int dst_slot, int src_slot,
                         int nr_items, gfp_t flags)
 {
-       struct tree_mod_elem *tm;
-       int ret;
+       struct tree_mod_elem *tm = NULL;
+       struct tree_mod_elem **tm_list = NULL;
+       int ret = 0;
        int i;
+       int locked = 0;
 
-       if (tree_mod_dont_log(fs_info, eb))
+       if (!tree_mod_need_log(fs_info, eb))
                return 0;
 
+       tm_list = kzalloc(nr_items * sizeof(struct tree_mod_elem *), flags);
+       if (!tm_list)
+               return -ENOMEM;
+
+       tm = kzalloc(sizeof(*tm), flags);
+       if (!tm) {
+               ret = -ENOMEM;
+               goto free_tms;
+       }
+
+       tm->index = eb->start >> PAGE_CACHE_SHIFT;
+       tm->slot = src_slot;
+       tm->move.dst_slot = dst_slot;
+       tm->move.nr_items = nr_items;
+       tm->op = MOD_LOG_MOVE_KEYS;
+
+       for (i = 0; i + dst_slot < src_slot && i < nr_items; i++) {
+               tm_list[i] = alloc_tree_mod_elem(eb, i + dst_slot,
+                   MOD_LOG_KEY_REMOVE_WHILE_MOVING, flags);
+               if (!tm_list[i]) {
+                       ret = -ENOMEM;
+                       goto free_tms;
+               }
+       }
+
+       if (tree_mod_dont_log(fs_info, eb))
+               goto free_tms;
+       locked = 1;
+
        /*
         * When we override something during the move, we log these removals.
         * This can only happen when we move towards the beginning of the
         * buffer, i.e. dst_slot < src_slot.
         */
        for (i = 0; i + dst_slot < src_slot && i < nr_items; i++) {
-               ret = __tree_mod_log_insert_key(fs_info, eb, i + dst_slot,
-                               MOD_LOG_KEY_REMOVE_WHILE_MOVING, GFP_NOFS);
-               BUG_ON(ret < 0);
+               ret = __tree_mod_log_insert(fs_info, tm_list[i]);
+               if (ret)
+                       goto free_tms;
        }
 
-       tm = kzalloc(sizeof(*tm), flags);
-       if (!tm)
-               return -ENOMEM;
+       ret = __tree_mod_log_insert(fs_info, tm);
+       if (ret)
+               goto free_tms;
+       tree_mod_log_write_unlock(fs_info);
+       kfree(tm_list);
 
-       tm->index = eb->start >> PAGE_CACHE_SHIFT;
-       tm->slot = src_slot;
-       tm->move.dst_slot = dst_slot;
-       tm->move.nr_items = nr_items;
-       tm->op = MOD_LOG_MOVE_KEYS;
+       return 0;
+free_tms:
+       for (i = 0; i < nr_items; i++) {
+               if (tm_list[i] && !RB_EMPTY_NODE(&tm_list[i]->node))
+                       rb_erase(&tm_list[i]->node, &fs_info->tree_mod_log);
+               kfree(tm_list[i]);
+       }
+       if (locked)
+               tree_mod_log_write_unlock(fs_info);
+       kfree(tm_list);
+       kfree(tm);
 
-       return __tree_mod_log_insert(fs_info, tm);
+       return ret;
 }
 
-static inline void
-__tree_mod_log_free_eb(struct btrfs_fs_info *fs_info, struct extent_buffer *eb)
+static inline int
+__tree_mod_log_free_eb(struct btrfs_fs_info *fs_info,
+                      struct tree_mod_elem **tm_list,
+                      int nritems)
 {
-       int i;
-       u32 nritems;
+       int i, j;
        int ret;
 
-       if (btrfs_header_level(eb) == 0)
-               return;
-
-       nritems = btrfs_header_nritems(eb);
        for (i = nritems - 1; i >= 0; i--) {
-               ret = __tree_mod_log_insert_key(fs_info, eb, i,
-                               MOD_LOG_KEY_REMOVE_WHILE_FREEING, GFP_NOFS);
-               BUG_ON(ret < 0);
+               ret = __tree_mod_log_insert(fs_info, tm_list[i]);
+               if (ret) {
+                       for (j = nritems - 1; j > i; j--)
+                               rb_erase(&tm_list[j]->node,
+                                        &fs_info->tree_mod_log);
+                       return ret;
+               }
        }
+
+       return 0;
 }
 
 static noinline int
@@ -641,17 +702,38 @@ tree_mod_log_insert_root(struct btrfs_fs_info *fs_info,
                         struct extent_buffer *new_root, gfp_t flags,
                         int log_removal)
 {
-       struct tree_mod_elem *tm;
+       struct tree_mod_elem *tm = NULL;
+       struct tree_mod_elem **tm_list = NULL;
+       int nritems = 0;
+       int ret = 0;
+       int i;
 
-       if (tree_mod_dont_log(fs_info, NULL))
+       if (!tree_mod_need_log(fs_info, NULL))
                return 0;
 
-       if (log_removal)
-               __tree_mod_log_free_eb(fs_info, old_root);
+       if (log_removal && btrfs_header_level(old_root) > 0) {
+               nritems = btrfs_header_nritems(old_root);
+               tm_list = kzalloc(nritems * sizeof(struct tree_mod_elem *),
+                                 flags);
+               if (!tm_list) {
+                       ret = -ENOMEM;
+                       goto free_tms;
+               }
+               for (i = 0; i < nritems; i++) {
+                       tm_list[i] = alloc_tree_mod_elem(old_root, i,
+                           MOD_LOG_KEY_REMOVE_WHILE_FREEING, flags);
+                       if (!tm_list[i]) {
+                               ret = -ENOMEM;
+                               goto free_tms;
+                       }
+               }
+       }
 
        tm = kzalloc(sizeof(*tm), flags);
-       if (!tm)
-               return -ENOMEM;
+       if (!tm) {
+               ret = -ENOMEM;
+               goto free_tms;
+       }
 
        tm->index = new_root->start >> PAGE_CACHE_SHIFT;
        tm->old_root.logical = old_root->start;
@@ -659,7 +741,30 @@ tree_mod_log_insert_root(struct btrfs_fs_info *fs_info,
        tm->generation = btrfs_header_generation(old_root);
        tm->op = MOD_LOG_ROOT_REPLACE;
 
-       return __tree_mod_log_insert(fs_info, tm);
+       if (tree_mod_dont_log(fs_info, NULL))
+               goto free_tms;
+
+       if (tm_list)
+               ret = __tree_mod_log_free_eb(fs_info, tm_list, nritems);
+       if (!ret)
+               ret = __tree_mod_log_insert(fs_info, tm);
+
+       tree_mod_log_write_unlock(fs_info);
+       if (ret)
+               goto free_tms;
+       kfree(tm_list);
+
+       return ret;
+
+free_tms:
+       if (tm_list) {
+               for (i = 0; i < nritems; i++)
+                       kfree(tm_list[i]);
+               kfree(tm_list);
+       }
+       kfree(tm);
+
+       return ret;
 }
 
 static struct tree_mod_elem *
@@ -728,31 +833,75 @@ tree_mod_log_search(struct btrfs_fs_info *fs_info, u64 start, u64 min_seq)
        return __tree_mod_log_search(fs_info, start, min_seq, 0);
 }
 
-static noinline void
+static noinline int
 tree_mod_log_eb_copy(struct btrfs_fs_info *fs_info, struct extent_buffer *dst,
                     struct extent_buffer *src, unsigned long dst_offset,
                     unsigned long src_offset, int nr_items)
 {
-       int ret;
+       int ret = 0;
+       struct tree_mod_elem **tm_list = NULL;
+       struct tree_mod_elem **tm_list_add, **tm_list_rem;
        int i;
+       int locked = 0;
 
-       if (tree_mod_dont_log(fs_info, NULL))
-               return;
+       if (!tree_mod_need_log(fs_info, NULL))
+               return 0;
 
        if (btrfs_header_level(dst) == 0 && btrfs_header_level(src) == 0)
-               return;
+               return 0;
 
+       tm_list = kzalloc(nr_items * 2 * sizeof(struct tree_mod_elem *),
+                         GFP_NOFS);
+       if (!tm_list)
+               return -ENOMEM;
+
+       tm_list_add = tm_list;
+       tm_list_rem = tm_list + nr_items;
        for (i = 0; i < nr_items; i++) {
-               ret = __tree_mod_log_insert_key(fs_info, src,
-                                               i + src_offset,
-                                               MOD_LOG_KEY_REMOVE, GFP_NOFS);
-               BUG_ON(ret < 0);
-               ret = __tree_mod_log_insert_key(fs_info, dst,
-                                                    i + dst_offset,
-                                                    MOD_LOG_KEY_ADD,
-                                                    GFP_NOFS);
-               BUG_ON(ret < 0);
+               tm_list_rem[i] = alloc_tree_mod_elem(src, i + src_offset,
+                   MOD_LOG_KEY_REMOVE, GFP_NOFS);
+               if (!tm_list_rem[i]) {
+                       ret = -ENOMEM;
+                       goto free_tms;
+               }
+
+               tm_list_add[i] = alloc_tree_mod_elem(dst, i + dst_offset,
+                   MOD_LOG_KEY_ADD, GFP_NOFS);
+               if (!tm_list_add[i]) {
+                       ret = -ENOMEM;
+                       goto free_tms;
+               }
+       }
+
+       if (tree_mod_dont_log(fs_info, NULL))
+               goto free_tms;
+       locked = 1;
+
+       for (i = 0; i < nr_items; i++) {
+               ret = __tree_mod_log_insert(fs_info, tm_list_rem[i]);
+               if (ret)
+                       goto free_tms;
+               ret = __tree_mod_log_insert(fs_info, tm_list_add[i]);
+               if (ret)
+                       goto free_tms;
+       }
+
+       tree_mod_log_write_unlock(fs_info);
+       kfree(tm_list);
+
+       return 0;
+
+free_tms:
+       for (i = 0; i < nr_items * 2; i++) {
+               if (tm_list[i] && !RB_EMPTY_NODE(&tm_list[i]->node))
+                       rb_erase(&tm_list[i]->node, &fs_info->tree_mod_log);
+               kfree(tm_list[i]);
        }
+       if (locked)
+               tree_mod_log_write_unlock(fs_info);
+       kfree(tm_list);
+
+       return ret;
 }
 
 static inline void
@@ -777,12 +926,52 @@ tree_mod_log_set_node_key(struct btrfs_fs_info *fs_info,
        BUG_ON(ret < 0);
 }
 
-static noinline void
+static noinline int
 tree_mod_log_free_eb(struct btrfs_fs_info *fs_info, struct extent_buffer *eb)
 {
+       struct tree_mod_elem **tm_list = NULL;
+       int nritems = 0;
+       int i;
+       int ret = 0;
+
+       if (btrfs_header_level(eb) == 0)
+               return 0;
+
+       if (!tree_mod_need_log(fs_info, NULL))
+               return 0;
+
+       nritems = btrfs_header_nritems(eb);
+       tm_list = kzalloc(nritems * sizeof(struct tree_mod_elem *),
+                         GFP_NOFS);
+       if (!tm_list)
+               return -ENOMEM;
+
+       for (i = 0; i < nritems; i++) {
+               tm_list[i] = alloc_tree_mod_elem(eb, i,
+                   MOD_LOG_KEY_REMOVE_WHILE_FREEING, GFP_NOFS);
+               if (!tm_list[i]) {
+                       ret = -ENOMEM;
+                       goto free_tms;
+               }
+       }
+
        if (tree_mod_dont_log(fs_info, eb))
-               return;
-       __tree_mod_log_free_eb(fs_info, eb);
+               goto free_tms;
+
+       ret = __tree_mod_log_free_eb(fs_info, tm_list, nritems);
+       tree_mod_log_write_unlock(fs_info);
+       if (ret)
+               goto free_tms;
+       kfree(tm_list);
+
+       return 0;
+
+free_tms:
+       for (i = 0; i < nritems; i++)
+               kfree(tm_list[i]);
+       kfree(tm_list);
+
+       return ret;
 }
 
 static noinline void
@@ -1040,8 +1229,13 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
                btrfs_set_node_ptr_generation(parent, parent_slot,
                                              trans->transid);
                btrfs_mark_buffer_dirty(parent);
-               if (last_ref)
-                       tree_mod_log_free_eb(root->fs_info, buf);
+               if (last_ref) {
+                       ret = tree_mod_log_free_eb(root->fs_info, buf);
+                       if (ret) {
+                               btrfs_abort_transaction(trans, root, ret);
+                               return ret;
+                       }
+               }
                btrfs_free_tree_block(trans, root, buf, parent_start,
                                      last_ref);
        }
@@ -3064,8 +3258,12 @@ static int push_node_left(struct btrfs_trans_handle *trans,
        } else
                push_items = min(src_nritems - 8, push_items);
 
-       tree_mod_log_eb_copy(root->fs_info, dst, src, dst_nritems, 0,
-                            push_items);
+       ret = tree_mod_log_eb_copy(root->fs_info, dst, src, dst_nritems, 0,
+                                  push_items);
+       if (ret) {
+               btrfs_abort_transaction(trans, root, ret);
+               return ret;
+       }
        copy_extent_buffer(dst, src,
                           btrfs_node_key_ptr_offset(dst_nritems),
                           btrfs_node_key_ptr_offset(0),
@@ -3135,8 +3333,12 @@ static int balance_node_right(struct btrfs_trans_handle *trans,
                                      (dst_nritems) *
                                      sizeof(struct btrfs_key_ptr));
 
-       tree_mod_log_eb_copy(root->fs_info, dst, src, 0,
-                            src_nritems - push_items, push_items);
+       ret = tree_mod_log_eb_copy(root->fs_info, dst, src, 0,
+                                  src_nritems - push_items, push_items);
+       if (ret) {
+               btrfs_abort_transaction(trans, root, ret);
+               return ret;
+       }
        copy_extent_buffer(dst, src,
                           btrfs_node_key_ptr_offset(0),
                           btrfs_node_key_ptr_offset(src_nritems - push_items),
@@ -3337,7 +3539,12 @@ static noinline int split_node(struct btrfs_trans_handle *trans,
                            btrfs_header_chunk_tree_uuid(split),
                            BTRFS_UUID_SIZE);
 
-       tree_mod_log_eb_copy(root->fs_info, split, c, 0, mid, c_nritems - mid);
+       ret = tree_mod_log_eb_copy(root->fs_info, split, c, 0,
+                                  mid, c_nritems - mid);
+       if (ret) {
+               btrfs_abort_transaction(trans, root, ret);
+               return ret;
+       }
        copy_extent_buffer(split, c,
                           btrfs_node_key_ptr_offset(0),
                           btrfs_node_key_ptr_offset(mid),