fs: remove mapping->backing_dev_info

Now that we never use the backing_dev_info pointer in struct address_space
we can simply remove it and save 4 to 8 bytes in every inode.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Reviewed-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 0 insertions, 13 deletions

diff --git a/fs/inode.c b/fs/inode.c
index aa149e7262ac..e4e8caa7464c 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -170,20 +170,7 @@ int inode_init_always(struct super_block *sb, struct inode *inode)
         atomic_set(&mapping->i_mmap_writable, 0);
         mapping_set_gfp_mask(mapping, GFP_HIGHUSER_MOVABLE);
         mapping->private_data = NULL;
-        mapping->backing_dev_info = &default_backing_dev_info;
         mapping->writeback_index = 0;
-
-        /*
-         * If the block_device provides a backing_dev_info for client
-         * inodes then use that.  Otherwise the inode share the bdev's
-         * backing_dev_info.
-         */
-        if (sb->s_bdev) {
-                struct backing_dev_info *bdi;
-
-                bdi = sb->s_bdev->bd_inode->i_mapping->backing_dev_info;
-                mapping->backing_dev_info = bdi;
-        }
         inode->i_private = NULL;
         inode->i_mapping = mapping;
         INIT_HLIST_HEAD(&inode->i_dentry);      /* buggered by rcu freeing */