writeback: separate out include/linux/backing-dev-defs.h

With the planned cgroup writeback support, backing-dev related
declarations will be more widely used across block and cgroup;
unfortunately, including backing-dev.h from include/linux/blkdev.h
makes cyclic include dependency quite likely.

This patch separates out backing-dev-defs.h which only has the
essential definitions and updates blkdev.h to include it.  c files
which need access to more backing-dev details now include
backing-dev.h directly.  This takes backing-dev.h off the common
include dependency chain making it a lot easier to use it across block
and cgroup.

v2: fs/fat build failure fixed.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@fb.com>

14 files changed, 14 insertions, 0 deletions

diff --git a/fs/block_dev.c b/fs/block_dev.c
index c7e4163ede87..e545cbfbe5b2 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -14,6 +14,7 @@
 #include <linux/device_cgroup.h>
 #include <linux/highmem.h>
 #include <linux/blkdev.h>
+#include <linux/backing-dev.h>
 #include <linux/module.h>
 #include <linux/blkpg.h>
 #include <linux/magic.h>
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index d74e08029643..e8b5866ffa07 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -39,6 +39,7 @@
 #include <linux/slab.h>
 #include <asm/uaccess.h>
 #include <linux/fiemap.h>
+#include <linux/backing-dev.h>
 #include "ext4_jbd2.h"
 #include "ext4_extents.h"
 #include "xattr.h"
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 8d1e60214ef0..440987c8ba9e 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -26,6 +26,7 @@
 #include <linux/log2.h>
 #include <linux/module.h>
 #include <linux/slab.h>
+#include <linux/backing-dev.h>
 #include <trace/events/ext4.h>
 
 #ifdef CONFIG_EXT4_DEBUG
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index f06d0589ddba..56b8bb75c3fc 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -24,6 +24,7 @@
 #include <linux/slab.h>
 #include <linux/init.h>
 #include <linux/blkdev.h>
+#include <linux/backing-dev.h>
 #include <linux/parser.h>
 #include <linux/buffer_head.h>
 #include <linux/exportfs.h>
diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
index 6408989857e0..aba72f7a8ac4 100644
--- a/fs/f2fs/segment.h
+++ b/fs/f2fs/segment.h
@@ -9,6 +9,7 @@
  * published by the Free Software Foundation.
  */
 #include <linux/blkdev.h>
+#include <linux/backing-dev.h>
 
 /* constant macro */
 #define NULL_SEGNO			((unsigned int)(~0))
diff --git a/fs/fat/file.c b/fs/fat/file.c
index 442d50a0e33e..a08f1039909a 100644
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -11,6 +11,7 @@
 #include <linux/compat.h>
 #include <linux/mount.h>
 #include <linux/blkdev.h>
+#include <linux/backing-dev.h>
 #include <linux/fsnotify.h>
 #include <linux/security.h>
 #include "fat.h"
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index c06774658345..509411dd3698 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -18,6 +18,7 @@
 #include <linux/parser.h>
 #include <linux/uio.h>
 #include <linux/blkdev.h>
+#include <linux/backing-dev.h>
 #include <asm/unaligned.h>
 #include "fat.h"
 
diff --git a/fs/hfs/super.c b/fs/hfs/super.c
index eee7206c38d1..55c03b9e9070 100644
--- a/fs/hfs/super.c
+++ b/fs/hfs/super.c
@@ -14,6 +14,7 @@
 
 #include <linux/module.h>
 #include <linux/blkdev.h>
+#include <linux/backing-dev.h>
 #include <linux/mount.h>
 #include <linux/init.h>
 #include <linux/nls.h>
diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c
index 593af2fdcc2d..7302d96ae8bf 100644
--- a/fs/hfsplus/super.c
+++ b/fs/hfsplus/super.c
@@ -11,6 +11,7 @@
 #include <linux/init.h>
 #include <linux/pagemap.h>
 #include <linux/blkdev.h>
+#include <linux/backing-dev.h>
 #include <linux/fs.h>
 #include <linux/slab.h>
 #include <linux/vfs.h>
diff --git a/fs/nfs/filelayout/filelayout.c b/fs/nfs/filelayout/filelayout.c
index a46bf6de9ce4..b34f2e228601 100644
--- a/fs/nfs/filelayout/filelayout.c
+++ b/fs/nfs/filelayout/filelayout.c
@@ -32,6 +32,7 @@
 #include <linux/nfs_fs.h>
 #include <linux/nfs_page.h>
 #include <linux/module.h>
+#include <linux/backing-dev.h>
 
 #include <linux/sunrpc/metrics.h>
 
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index d8b670cbd909..8f1feca89fb0 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -37,6 +37,7 @@
 #include <linux/falloc.h>
 #include <linux/quotaops.h>
 #include <linux/blkdev.h>
+#include <linux/backing-dev.h>
 
 #include <cluster/masklog.h>
 
diff --git a/fs/reiserfs/super.c b/fs/reiserfs/super.c
index 0111ad0466ed..3e0af317fcc3 100644
--- a/fs/reiserfs/super.c
+++ b/fs/reiserfs/super.c
@@ -21,6 +21,7 @@
 #include "xattr.h"
 #include <linux/init.h>
 #include <linux/blkdev.h>
+#include <linux/backing-dev.h>
 #include <linux/buffer_head.h>
 #include <linux/exportfs.h>
 #include <linux/quotaops.h>
diff --git a/fs/ufs/super.c b/fs/ufs/super.c
index b3bc3e7ae79d..098508a93c7b 100644
--- a/fs/ufs/super.c
+++ b/fs/ufs/super.c
@@ -80,6 +80,7 @@
 #include <linux/stat.h>
 #include <linux/string.h>
 #include <linux/blkdev.h>
+#include <linux/backing-dev.h>
 #include <linux/init.h>
 #include <linux/parser.h>
 #include <linux/buffer_head.h>
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 8121e75352ee..4e00b38efbe0 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -41,6 +41,7 @@
 #include <linux/dcache.h>
 #include <linux/falloc.h>
 #include <linux/pagevec.h>
+#include <linux/backing-dev.h>
 
 static const struct vm_operations_struct xfs_file_vm_ops;