[PATCH 08/12] fs: remove mapping->backing_dev_info

Christoph Hellwig
2015-01-08T17:45:29Z

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>
---
drivers/char/raw.c | 4 +---
fs/aio.c | 1 -
fs/block_dev.c | 26 +-------------------------
fs/btrfs/disk-io.c | 1 -
fs/btrfs/inode.c | 6 ------
fs/ceph/inode.c | 2 --
fs/cifs/inode.c | 2 --
fs/configfs/inode.c | 1 -
fs/ecryptfs/inode.c | 1 -
fs/exofs/inode.c | 2 --
fs/fuse/inode.c | 1 -
fs/gfs2/glock.c | 1 -
fs/gfs2/ops_fstype.c | 1 -
fs/hugetlbfs/inode.c | 1 -
fs/inode.c | 13 -------------
fs/kernfs/inode.c | 1 -
fs/ncpfs/inode.c | 1 -
fs/nfs/inode.c | 1 -
fs/nilfs2/gcinode.c | 1 -
fs/nilfs2/mdt.c | 6 ++----
fs/nilfs2/page.c | 4 +---
fs/nilfs2/page.h | 3 +--
fs/nilfs2/super.c | 2 +-
fs/ocfs2/dlmfs/dlmfs.c | 2 --
fs/ramfs/inode.c | 1 -
fs/romfs/super.c | 3 ---
fs/ubifs/dir.c | 2 --
fs/ubifs/super.c | 3 ---
include/linux/fs.h | 3 +--
mm/backing-dev.c | 1 -
mm/shmem.c | 1 -
mm/swap_state.c | 1 -
32 files changed, 8 insertions(+), 91 deletions(-)

diff --git a/drivers/char/raw.c b/drivers/char/raw.c
index a24891b..6e29bf2 100644
--- a/drivers/char/raw.c
+++ b/drivers/char/raw.c
@@ -104,11 +104,9 @@ static int raw_release(struct inode *inode, struct file *filp)

mutex_lock(&raw_mutex);
bdev = raw_devices[minor].binding;
- if (--raw_devices[minor].inuse == 0) {
+ if (--raw_devices[minor].inuse == 0)
/* Here inode->i_mapping == bdev->bd_inode->i_mapping */
inode->i_mapping = &inode->i_data;
- inode->i_mapping->backing_dev_info = &default_backing_dev_info;
- }
mutex_unlock(&raw_mutex);

blkdev_put(bdev, filp->f_mode | FMODE_EXCL);
diff --git a/fs/aio.c b/fs/aio.c
index 6f13d3f..3bf8b1d 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -176,7 +176,6 @@ static struct file *aio_private_file(struct kioctx *ctx, loff_t nr_pages)

inode->i_mapping->a_ops = &aio_ctx_aops;
inode->i_mapping->private_data = ctx;
- inode->i_mapping->backing_dev_info = &noop_backing_dev_info;
inode->i_size = PAGE_SIZE * nr_pages;

path.dentry = d_alloc_pseudo(aio_mnt->mnt_sb, &this);
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 288ba70..2ec7b3d 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -60,19 +60,6 @@ static void bdev_write_inode(struct inode *inode)
spin_unlock(&inode->i_lock);
}

-/*
- * Move the inode from its current bdi to a new bdi. Make sure the inode
- * is clean before moving so that it doesn't linger on the old bdi.
- */
-static void bdev_inode_switch_bdi(struct inode *inode,
- struct backing_dev_info *dst)
-{
- spin_lock(&inode->i_lock);
- WARN_ON_ONCE(inode->i_state & I_DIRTY);
- inode->i_data.backing_dev_info = dst;
- spin_unlock(&inode->i_lock);
-}
-
/* Kill _all_ buffers and pagecache , dirty or not.. */
void kill_bdev(struct block_device *bdev)
{
@@ -589,7 +576,6 @@ struct block_device *bdget(dev_t dev)
inode->i_bdev = bdev;
inode->i_data.a_ops = &def_blk_aops;
mapping_set_gfp_mask(&inode->i_data, GFP_USER);
- inode->i_data.backing_dev_info = &default_backing_dev_info;
spin_lock(&bdev_lock);
list_add(&bdev->bd_list, &all_bdevs);
spin_unlock(&bdev_lock);
@@ -1150,8 +1136,6 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
bdev->bd_queue = disk->queue;
bdev->bd_contains = bdev;
if (!partno) {
- struct backing_dev_info *bdi;
-
ret = -ENXIO;
bdev->bd_part = disk_get_part(disk, partno);
if (!bdev->bd_part)
@@ -1177,11 +1161,8 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
}
}

- if (!ret) {
+ if (!ret)
bd_set_size(bdev,(loff_t)get_capacity(disk)<<9);
- bdi = blk_get_backing_dev_info(bdev);
- bdev_inode_switch_bdi(bdev->bd_inode, bdi);
- }

/*
* If the device is invalidated, rescan partition
@@ -1208,8 +1189,6 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
if (ret)
goto out_clear;
bdev->bd_contains = whole;
- bdev_inode_switch_bdi(bdev->bd_inode,
- whole->bd_inode->i_data.backing_dev_info);
bdev->bd_part = disk_get_part(disk, partno);
if (!(disk->flags & GENHD_FL_UP) ||
!bdev->bd_part || !bdev->bd_part->nr_sects) {
@@ -1249,7 +1228,6 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
bdev->bd_disk = NULL;
bdev->bd_part = NULL;
bdev->bd_queue = NULL;
- bdev_inode_switch_bdi(bdev->bd_inode, &default_backing_dev_info);
if (bdev != bdev->bd_contains)
__blkdev_put(bdev->bd_contains, mode, 1);
bdev->bd_contains = NULL;
@@ -1474,8 +1452,6 @@ static void __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part)
* dirty data before.
*/
bdev_write_inode(bdev->bd_inode);
- bdev_inode_switch_bdi(bdev->bd_inode,
- &default_backing_dev_info);
}
if (bdev->bd_contains == bdev) {
if (disk->fops->release)
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index afc4092..1ec872e 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2318,7 +2318,6 @@ int open_ctree(struct super_block *sb,
*/
fs_info->btree_inode->i_size = OFFSET_MAX;
fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
- fs_info->btree_inode->i_mapping->backing_dev_info = &fs_info->bdi;

RB_CLEAR_NODE(&BTRFS_I(fs_info->btree_inode)->rb_node);
extent_io_tree_init(&BTRFS_I(fs_info->btree_inode)->io_tree,
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index e687bb0..5a4046a 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -3608,7 +3608,6 @@ cache_acl:
switch (inode->i_mode & S_IFMT) {
case S_IFREG:
inode->i_mapping->a_ops = &btrfs_aops;
- inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
inode->i_fop = &btrfs_file_operations;
inode->i_op = &btrfs_file_inode_operations;
@@ -3623,7 +3622,6 @@ cache_acl:
case S_IFLNK:
inode->i_op = &btrfs_symlink_inode_operations;
inode->i_mapping->a_ops = &btrfs_symlink_aops;
- inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
break;
default:
inode->i_op = &btrfs_special_inode_operations;
@@ -6088,7 +6086,6 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
inode->i_fop = &btrfs_file_operations;
inode->i_op = &btrfs_file_inode_operations;
inode->i_mapping->a_ops = &btrfs_aops;
- inode->i_mapping->backing_dev_info = &root->fs_info->bdi;

err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
if (err)
@@ -9201,7 +9198,6 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
inode->i_fop = &btrfs_file_operations;
inode->i_op = &btrfs_file_inode_operations;
inode->i_mapping->a_ops = &btrfs_aops;
- inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;

err = btrfs_init_inode_security(trans, inode, dir, &dentry->d_name);
@@ -9245,7 +9241,6 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,

inode->i_op = &btrfs_symlink_inode_operations;
inode->i_mapping->a_ops = &btrfs_symlink_aops;
- inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
inode_set_bytes(inode, name_len);
btrfs_i_size_write(inode, name_len);
err = btrfs_update_inode(trans, root, inode);
@@ -9457,7 +9452,6 @@ static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
inode->i_op = &btrfs_file_inode_operations;

inode->i_mapping->a_ops = &btrfs_aops;
- inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;

ret = btrfs_init_inode_security(trans, inode, dir, NULL);
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index f61a741..6b51736 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -783,8 +783,6 @@ static int fill_inode(struct inode *inode, struct page *locked_page,
}

inode->i_mapping->a_ops = &ceph_aops;
- inode->i_mapping->backing_dev_info =
- &ceph_sb_to_client(inode->i_sb)->backing_dev_info;

switch (inode->i_mode & S_IFMT) {
case S_IFIFO:
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 0c3ce464..2d4f372 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -937,8 +937,6 @@ retry_iget5_locked:
inode->i_flags |= S_NOATIME | S_NOCMTIME;
if (inode->i_state & I_NEW) {
inode->i_ino = hash;
- if (S_ISREG(inode->i_mode))
- inode->i_data.backing_dev_info = sb->s_bdi;
#ifdef CONFIG_CIFS_FSCACHE
/* initialize per-inode cache cookie pointer */
CIFS_I(inode)->fscache = NULL;
diff --git a/fs/configfs/inode.c b/fs/configfs/inode.c
index 0ad6b4d..65af861 100644
--- a/fs/configfs/inode.c
+++ b/fs/configfs/inode.c
@@ -131,7 +131,6 @@ struct inode *configfs_new_inode(umode_t mode, struct configfs_dirent *sd,
if (inode) {
inode->i_ino = get_next_ino();
inode->i_mapping->a_ops = &configfs_aops;
- inode->i_mapping->backing_dev_info = &noop_backing_dev_info;
inode->i_op = &configfs_inode_operations;

if (sd->s_iattr) {
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 1686dc2..34b36a5 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -67,7 +67,6 @@ static int ecryptfs_inode_set(struct inode *inode, void *opaque)
inode->i_ino = lower_inode->i_ino;
inode->i_version++;
inode->i_mapping->a_ops = &ecryptfs_aops;
- inode->i_mapping->backing_dev_info = inode->i_sb->s_bdi;

if (S_ISLNK(inode->i_mode))
inode->i_op = &ecryptfs_symlink_iops;
diff --git a/fs/exofs/inode.c b/fs/exofs/inode.c
index f1d3d4e..6fc91df 100644
--- a/fs/exofs/inode.c
+++ b/fs/exofs/inode.c
@@ -1214,7 +1214,6 @@ struct inode *exofs_iget(struct super_block *sb, unsigned long ino)
memcpy(oi->i_data, fcb.i_data, sizeof(fcb.i_data));
}

- inode->i_mapping->backing_dev_info = sb->s_bdi;
if (S_ISREG(inode->i_mode)) {
inode->i_op = &exofs_file_inode_operations;
inode->i_fop = &exofs_file_operations;
@@ -1314,7 +1313,6 @@ struct inode *exofs_new_inode(struct inode *dir, umode_t mode)

set_obj_2bcreated(oi);

- inode->i_mapping->backing_dev_info = sb->s_bdi;
inode_init_owner(inode, dir, mode);
inode->i_ino = sbi->s_nextid++;
inode->i_blkbits = EXOFS_BLKSHIFT;
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 6749109..ea0aacd 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -308,7 +308,6 @@ struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
if (!fc->writeback_cache || !S_ISREG(attr->mode))
inode->i_flags |= S_NOCMTIME;
inode->i_generation = generation;
- inode->i_data.backing_dev_info = &fc->bdi;
fuse_init_inode(inode, attr);
unlock_new_inode(inode);
} else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index a23524a..08ea717 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -775,7 +775,6 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
mapping->flags = 0;
mapping_set_gfp_mask(mapping, GFP_NOFS);
mapping->private_data = NULL;
- mapping->backing_dev_info = s->s_bdi;
mapping->writeback_index = 0;
}

diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index 8633ad3..efc8e25 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -112,7 +112,6 @@ static struct gfs2_sbd *init_sbd(struct super_block *sb)
mapping->flags = 0;
mapping_set_gfp_mask(mapping, GFP_NOFS);
mapping->private_data = NULL;
- mapping->backing_dev_info = sb->s_bdi;
mapping->writeback_index = 0;

spin_lock_init(&sdp->sd_log_lock);
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index de7c95c..c274aca 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -492,7 +492,6 @@ static struct inode *hugetlbfs_get_inode(struct super_block *sb,
lockdep_set_class(&inode->i_mapping->i_mmap_rwsem,
&hugetlbfs_i_mmap_rwsem_key);
inode->i_mapping->a_ops = &hugetlbfs_aops;
- inode->i_mapping->backing_dev_info = &noop_backing_dev_info;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
inode->i_mapping->private_data = resv_map;
info = HUGETLBFS_I(inode);
diff --git a/fs/inode.c b/fs/inode.c
index aa149e7..e4e8caa 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 */
diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
index 06f0688..9000874 100644
--- a/fs/kernfs/inode.c
+++ b/fs/kernfs/inode.c
@@ -286,7 +286,6 @@ static void kernfs_init_inode(struct kernfs_node *kn, struct inode *inode)
kernfs_get(kn);
inode->i_private = kn;
inode->i_mapping->a_ops = &kernfs_aops;
- inode->i_mapping->backing_dev_info = &noop_backing_dev_info;
inode->i_op = &kernfs_iops;

set_default_inode_attr(inode, kn->mode);
diff --git a/fs/ncpfs/inode.c b/fs/ncpfs/inode.c
index a699a3f..01a9e16 100644
--- a/fs/ncpfs/inode.c
+++ b/fs/ncpfs/inode.c
@@ -267,7 +267,6 @@ ncp_iget(struct super_block *sb, struct ncp_entry_info *info)
if (inode) {
atomic_set(&NCP_FINFO(inode)->opened, info->opened);

- inode->i_mapping->backing_dev_info = sb->s_bdi;
inode->i_ino = info->ino;
ncp_set_attr(inode, info);
if (S_ISREG(inode->i_mode)) {
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 4bffe63..24aac72 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -387,7 +387,6 @@ nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr, st
if (S_ISREG(inode->i_mode)) {
inode->i_fop = NFS_SB(sb)->nfs_client->rpc_ops->file_ops;
inode->i_data.a_ops = &nfs_file_aops;
- inode->i_data.backing_dev_info = &NFS_SB(sb)->backing_dev_info;
} else if (S_ISDIR(inode->i_mode)) {
inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->dir_inode_ops;
inode->i_fop = &nfs_dir_operations;
diff --git a/fs/nilfs2/gcinode.c b/fs/nilfs2/gcinode.c
index 57ceaf3..748ca23 100644
--- a/fs/nilfs2/gcinode.c
+++ b/fs/nilfs2/gcinode.c
@@ -172,7 +172,6 @@ int nilfs_init_gcinode(struct inode *inode)
inode->i_mode = S_IFREG;
mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);
inode->i_mapping->a_ops = &empty_aops;
- inode->i_mapping->backing_dev_info = inode->i_sb->s_bdi;

ii->i_flags = 0;
nilfs_bmap_init_gc(ii->i_bmap);
diff --git a/fs/nilfs2/mdt.c b/fs/nilfs2/mdt.c
index c4dcd1d..892cf5f 100644
--- a/fs/nilfs2/mdt.c
+++ b/fs/nilfs2/mdt.c
@@ -429,7 +429,6 @@ int nilfs_mdt_init(struct inode *inode, gfp_t gfp_mask, size_t objsz)

inode->i_mode = S_IFREG;
mapping_set_gfp_mask(inode->i_mapping, gfp_mask);
- inode->i_mapping->backing_dev_info = inode->i_sb->s_bdi;

inode->i_op = &def_mdt_iops;
inode->i_fop = &def_mdt_fops;
@@ -457,13 +456,12 @@ int nilfs_mdt_setup_shadow_map(struct inode *inode,
struct nilfs_shadow_map *shadow)
{
struct nilfs_mdt_info *mi = NILFS_MDT(inode);
- struct backing_dev_info *bdi = inode->i_sb->s_bdi;

INIT_LIST_HEAD(&shadow->frozen_buffers);
address_space_init_once(&shadow->frozen_data);
- nilfs_mapping_init(&shadow->frozen_data, inode, bdi);
+ nilfs_mapping_init(&shadow->frozen_data, inode);
address_space_init_once(&shadow->frozen_btnodes);
- nilfs_mapping_init(&shadow->frozen_btnodes, inode, bdi);
+ nilfs_mapping_init(&shadow->frozen_btnodes, inode);
mi->mi_shadow = shadow;
return 0;
}
diff --git a/fs/nilfs2/page.c b/fs/nilfs2/page.c
index da27664..700ecbc 100644
--- a/fs/nilfs2/page.c
+++ b/fs/nilfs2/page.c
@@ -461,14 +461,12 @@ unsigned nilfs_page_count_clean_buffers(struct page *page,
return nc;
}

-void nilfs_mapping_init(struct address_space *mapping, struct inode *inode,
- struct backing_dev_info *bdi)
+void nilfs_mapping_init(struct address_space *mapping, struct inode *inode)
{
mapping->host = inode;
mapping->flags = 0;
mapping_set_gfp_mask(mapping, GFP_NOFS);
mapping->private_data = NULL;
- mapping->backing_dev_info = bdi;
mapping->a_ops = &empty_aops;
}

diff --git a/fs/nilfs2/page.h b/fs/nilfs2/page.h
index ef30c5c..a43b828 100644
--- a/fs/nilfs2/page.h
+++ b/fs/nilfs2/page.h
@@ -57,8 +57,7 @@ int nilfs_copy_dirty_pages(struct address_space *, struct address_space *);
void nilfs_copy_back_pages(struct address_space *, struct address_space *);
void nilfs_clear_dirty_page(struct page *, bool);
void nilfs_clear_dirty_pages(struct address_space *, bool);
-void nilfs_mapping_init(struct address_space *mapping, struct inode *inode,
- struct backing_dev_info *bdi);
+void nilfs_mapping_init(struct address_space *mapping, struct inode *inode);
unsigned nilfs_page_count_clean_buffers(struct page *, unsigned, unsigned);
unsigned long nilfs_find_uncommitted_extent(struct inode *inode,
sector_t start_blk,
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index 3d4bbac..5bc2a1c 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -166,7 +166,7 @@ struct inode *nilfs_alloc_inode(struct super_block *sb)
ii->i_state = 0;
ii->i_cno = 0;
ii->vfs_inode.i_version = 1;
- nilfs_mapping_init(&ii->i_btnode_cache, &ii->vfs_inode, sb->s_bdi);
+ nilfs_mapping_init(&ii->i_btnode_cache, &ii->vfs_inode);
return &ii->vfs_inode;
}

diff --git a/fs/ocfs2/dlmfs/dlmfs.c b/fs/ocfs2/dlmfs/dlmfs.c
index 6000d30..061ba6a 100644
--- a/fs/ocfs2/dlmfs/dlmfs.c
+++ b/fs/ocfs2/dlmfs/dlmfs.c
@@ -398,7 +398,6 @@ static struct inode *dlmfs_get_root_inode(struct super_block *sb)
if (inode) {
inode->i_ino = get_next_ino();
inode_init_owner(inode, NULL, mode);
- inode->i_mapping->backing_dev_info = &noop_backing_dev_info;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
inc_nlink(inode);

@@ -422,7 +421,6 @@ static struct inode *dlmfs_get_inode(struct inode *parent,

inode->i_ino = get_next_ino();
inode_init_owner(inode, parent, mode);
- inode->i_mapping->backing_dev_info = &noop_backing_dev_info;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;

ip = DLMFS_I(inode);
diff --git a/fs/ramfs/inode.c b/fs/ramfs/inode.c
index ad4d712..889d558 100644
--- a/fs/ramfs/inode.c
+++ b/fs/ramfs/inode.c
@@ -59,7 +59,6 @@ struct inode *ramfs_get_inode(struct super_block *sb,
inode->i_ino = get_next_ino();
inode_init_owner(inode, dir, mode);
inode->i_mapping->a_ops = &ramfs_aops;
- inode->i_mapping->backing_dev_info = &noop_backing_dev_info;
mapping_set_gfp_mask(inode->i_mapping, GFP_HIGHUSER);
mapping_set_unevictable(inode->i_mapping);
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
diff --git a/fs/romfs/super.c b/fs/romfs/super.c
index e98dd88..268733c 100644
--- a/fs/romfs/super.c
+++ b/fs/romfs/super.c
@@ -355,9 +355,6 @@ static struct inode *romfs_iget(struct super_block *sb, unsigned long pos)
case ROMFH_REG:
i->i_fop = &romfs_ro_fops;
i->i_data.a_ops = &romfs_aops;
- if (i->i_sb->s_mtd)
- i->i_data.backing_dev_info =
- i->i_sb->s_mtd->backing_dev_info;
if (nextfh & ROMFH_EXEC)
mode |= S_IXUGO;
break;
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index ea41649..c49b198 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 ed93dc6..6197154 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;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 7939a2e..6484bb4 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -34,6 +34,7 @@
#include <asm/byteorder.h>
#include <uapi/linux/fs.h>

+struct backing_dev_info;
struct export_operations;
struct hd_geometry;
struct iovec;
@@ -394,7 +395,6 @@ int pagecache_write_end(struct file *, struct address_space *mapping,
loff_t pos, unsigned len, unsigned copied,
struct page *page, void *fsdata);

-struct backing_dev_info;
struct address_space {
struct inode *host; /* owner: inode, block_device */
struct radix_tree_root page_tree; /* radix tree of all pages */
@@ -409,7 +409,6 @@ struct address_space {
pgoff_t writeback_index;/* writeback starts here */
const struct address_space_operations *a_ops; /* methods */
unsigned long flags; /* error bits/gfp mask */
- struct backing_dev_info *backing_dev_info; /* device readahead, etc */
spinlock_t private_lock; /* for use by the address_space */
struct list_head private_list; /* ditto */
void *private_data; /* ditto */
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 16c6895..52e0c76 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -24,7 +24,6 @@ struct backing_dev_info noop_backing_dev_info = {
.name = "noop",
.capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK,
};
-EXPORT_SYMBOL_GPL(noop_backing_dev_info);

static struct class *bdi_class;

diff --git a/mm/shmem.c b/mm/shmem.c
index 1b77eaf..4c61d3d 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1410,7 +1410,6 @@ static struct inode *shmem_get_inode(struct super_block *sb, const struct inode
inode->i_ino = get_next_ino();
inode_init_owner(inode, dir, mode);
inode->i_blocks = 0;
- inode->i_mapping->backing_dev_info = &noop_backing_dev_info;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
inode->i_generation = get_seconds();
info = SHMEM_I(inode);
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 1c137b6..405923f 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -37,7 +37,6 @@ struct address_space swapper_spaces[MAX_SWAPFILES] = {
.page_tree = RADIX_TREE_INIT(GFP_ATOMIC|__GFP_NOWARN),
.i_mmap_writable = ATOMIC_INIT(0),
.a_ops = &swap_aops,
- .backing_dev_info = &noop_backing_dev_info,
}
};

--
1.9.1