4.4-stable review patch. If anyone has any objections, please let me know.
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From: Josef Bacik jbacik@fb.com
[ Upstream commit b77000ed558daa3bef0899d29bf171b8c9b5e6a8 ]
If we fail to prepare our pages for whatever reason (out of memory in our case) we need to make sure to drop the block_group->data_rwsem, otherwise hilarity ensues.
Signed-off-by: Josef Bacik jbacik@fb.com Reviewed-by: Omar Sandoval osandov@fb.com Reviewed-by: Liu Bo bo.li.liu@oracle.com Reviewed-by: David Sterba dsterba@suse.com [ add label and use existing unlocking code ] Signed-off-by: David Sterba dsterba@suse.com
Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/btrfs/free-space-cache.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/fs/btrfs/free-space-cache.c +++ b/fs/btrfs/free-space-cache.c @@ -1258,7 +1258,7 @@ static int __btrfs_write_out_cache(struc /* Lock all pages first so we can lock the extent safely. */ ret = io_ctl_prepare_pages(io_ctl, inode, 0); if (ret) - goto out; + goto out_unlock;
lock_extent_bits(&BTRFS_I(inode)->io_tree, 0, i_size_read(inode) - 1, 0, &cached_state); @@ -1351,6 +1351,7 @@ out_nospc_locked: out_nospc: cleanup_write_cache_enospc(inode, io_ctl, &cached_state, &bitmap_list);
+out_unlock: if (block_group && (block_group->flags & BTRFS_BLOCK_GROUP_DATA)) up_write(&block_group->data_rwsem);