[PATCH 3.4 001/107] Btrfs: use kmem_cache_free when freeing entry in inode cache

lizf
2016-03-16T08:06:57Z

From: Filipe Manana <fdmanana@suse.com>

3.4.111-rc1 review patch. If anyone has any objections, please let me know.

------------------

commit c3f4a1685bb87e59c886ee68f7967eae07d4dffa upstream.

The free space entries are allocated using kmem_cache_zalloc(),
through __btrfs_add_free_space(), therefore we should use
kmem_cache_free() and not kfree() to avoid any confusion and
any potential problem. Looking at the kfree() definition at
mm/slab.c it has the following comment:

/*
* (...)
*
* Don't free memory not originally allocated by kmalloc()
* or you will run into trouble.
*/

So better be safe and use kmem_cache_free().

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Zefan Li <lizefan@huawei.com>
---
fs/btrfs/inode-map.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c
index b1a1c92..47abfd2 100644
--- a/fs/btrfs/inode-map.c
+++ b/fs/btrfs/inode-map.c
@@ -283,7 +283,7 @@ void btrfs_unpin_free_ino(struct btrfs_root *root)
__btrfs_add_free_space(ctl, info->offset, count);
free:
rb_erase(&info->offset_index, rbroot);
- kfree(info);
+ kmem_cache_free(btrfs_free_space_cachep, info);
}
}

--
1.9.1