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>

2 files changed, 0 insertions, 5 deletions

diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index ea41649e4ca5..c49b1981ac95 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -108,8 +108,6 @@ struct inode *ubifs_new_inode(struct ubifs_info *c, const struct inode *dir,
         inode->i_mtime = inode->i_atime = inode->i_ctime =
                          ubifs_current_time(inode);
         inode->i_mapping->nrpages = 0;
-        /* Disable readahead */
-        inode->i_mapping->backing_dev_info = &c->bdi;
 
         switch (mode & S_IFMT) {
         case S_IFREG:
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index ed93dc6ae245..6197154f36ca 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -156,9 +156,6 @@ struct inode *ubifs_iget(struct super_block *sb, unsigned long inum)
         if (err)
                 goto out_invalid;
 
-        /* Disable read-ahead */
-        inode->i_mapping->backing_dev_info = &c->bdi;
-
         switch (inode->i_mode & S_IFMT) {
         case S_IFREG:
                 inode->i_mapping->a_ops = &ubifs_file_address_operations;