[PATCH 4.18 343/350] btrfs: fix insert_reserved error handling

Greg Kroah-Hartman
2018-11-11T23:12:51Z

From: Josef Bacik <josef@toxicpanda.com>

commit 80ee54bfe8a3850015585ebc84e8d207fcae6831 upstream.

We were not handling the reserved byte accounting properly for data
references. Metadata was fine, if it errored out the error paths would
free the bytes_reserved count and pin the extent, but it even missed one
of the error cases. So instead move this handling up into
run_one_delayed_ref so we are sure that both cases are properly cleaned
up in case of a transaction abort.

CC: stable@vger.kernel.org # 4.18+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/btrfs/extent-tree.c | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)

--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -2490,6 +2490,9 @@ static int run_one_delayed_ref(struct bt
insert_reserved);
else
BUG();
+ if (ret && insert_reserved)
+ btrfs_pin_extent(trans->fs_info, node->bytenr,
+ node->num_bytes, 1);
return ret;
}

@@ -8158,21 +8161,14 @@ static int alloc_reserved_tree_block(str
}

path = btrfs_alloc_path();
- if (!path) {
- btrfs_free_and_pin_reserved_extent(fs_info,
- extent_key.objectid,
- fs_info->nodesize);
+ if (!path)
return -ENOMEM;
- }

path->leave_spinning = 1;
ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
&extent_key, size);
if (ret) {
btrfs_free_path(path);
- btrfs_free_and_pin_reserved_extent(fs_info,
- extent_key.objectid,
- fs_info->nodesize);
return ret;
}