fs: pass exact type of data dirties to ->dirty_inode

Tell the filesystem if we just updated timestamp (I_DIRTY_SYNC) or
anything else, so that the filesystem can track internally if it
needs to push out a transaction for fdatasync or not.

This is just the prototype change with no user for it yet.  I plan
to push large XFS changes for the next merge window, and getting
this trivial infrastructure in this window would help a lot to avoid
tree interdependencies.

Also remove incorrect comments that ->dirty_inode can't block.  That
has been changed a long time ago, and many implementations rely on it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 61b31ac..57d827d6 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -104,7 +104,7 @@
 prototypes:
 	struct inode *(*alloc_inode)(struct super_block *sb);
 	void (*destroy_inode)(struct inode *);
-	void (*dirty_inode) (struct inode *);
+	void (*dirty_inode) (struct inode *, int flags);
 	int (*write_inode) (struct inode *, struct writeback_control *wbc);
 	int (*drop_inode) (struct inode *);
 	void (*evict_inode) (struct inode *);
@@ -126,7 +126,7 @@
 			s_umount
 alloc_inode:
 destroy_inode:
-dirty_inode:				(must not sleep)
+dirty_inode:
 write_inode:
 drop_inode:				!!!inode->i_lock!!!
 evict_inode:
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index 21a7dc4..88b9f55 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -211,7 +211,7 @@
         struct inode *(*alloc_inode)(struct super_block *sb);
         void (*destroy_inode)(struct inode *);
 
-        void (*dirty_inode) (struct inode *);
+        void (*dirty_inode) (struct inode *, int flags);
         int (*write_inode) (struct inode *, int);
         void (*drop_inode) (struct inode *);
         void (*delete_inode) (struct inode *);
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 8f4b81d..d2177e7 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2522,7 +2522,7 @@
 void btrfs_evict_inode(struct inode *inode);
 void btrfs_put_inode(struct inode *inode);
 int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc);
-void btrfs_dirty_inode(struct inode *inode);
+void btrfs_dirty_inode(struct inode *inode, int flags);
 struct inode *btrfs_alloc_inode(struct super_block *sb);
 void btrfs_destroy_inode(struct inode *inode);
 int btrfs_drop_inode(struct inode *inode);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 7cd8ab0..ecff7d7 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4396,7 +4396,7 @@
  * FIXME, needs more benchmarking...there are no reasons other than performance
  * to keep or drop this code.
  */
-void btrfs_dirty_inode(struct inode *inode)
+void btrfs_dirty_inode(struct inode *inode, int flags)
 {
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_trans_handle *trans;
diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index 68b2e43..3451d23 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -3392,7 +3392,7 @@
  * so would cause a commit on atime updates, which we don't bother doing.
  * We handle synchronous inodes at the highest possible level.
  */
-void ext3_dirty_inode(struct inode *inode)
+void ext3_dirty_inode(struct inode *inode, int flags)
 {
 	handle_t *current_handle = ext3_journal_current_handle();
 	handle_t *handle;
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index a74b89c..1921392 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1813,7 +1813,7 @@
 extern void ext4_evict_inode(struct inode *);
 extern void ext4_clear_inode(struct inode *);
 extern int  ext4_sync_inode(handle_t *, struct inode *);
-extern void ext4_dirty_inode(struct inode *);
+extern void ext4_dirty_inode(struct inode *, int);
 extern int ext4_change_inode_journal_flag(struct inode *, int);
 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
 extern int ext4_can_truncate(struct inode *inode);
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 50d0e9c..a5763e3 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5733,7 +5733,7 @@
  * so would cause a commit on atime updates, which we don't bother doing.
  * We handle synchronous inodes at the highest possible level.
  */
-void ext4_dirty_inode(struct inode *inode)
+void ext4_dirty_inode(struct inode *inode, int flags)
 {
 	handle_t *handle;
 
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 34591ee8..0f015a0 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -1007,9 +1007,6 @@
  * In short, make sure you hash any inodes _before_ you start marking
  * them dirty.
  *
- * This function *must* be atomic for the I_DIRTY_PAGES case -
- * set_page_dirty() is called under spinlock in several places.
- *
  * Note that for blockdevs, inode->dirtied_when represents the dirtying time of
  * the block-special inode (/dev/hda1) itself.  And the ->dirtied_when field of
  * the kernel-internal blockdev inode represents the dirtying time of the
@@ -1028,7 +1025,7 @@
 	 */
 	if (flags & (I_DIRTY_SYNC | I_DIRTY_DATASYNC)) {
 		if (sb->s_op->dirty_inode)
-			sb->s_op->dirty_inode(inode);
+			sb->s_op->dirty_inode(inode, flags);
 	}
 
 	/*
diff --git a/fs/jffs2/fs.c b/fs/jffs2/fs.c
index e896e67..46ad619 100644
--- a/fs/jffs2/fs.c
+++ b/fs/jffs2/fs.c
@@ -357,7 +357,7 @@
 	return ERR_PTR(ret);
 }
 
-void jffs2_dirty_inode(struct inode *inode)
+void jffs2_dirty_inode(struct inode *inode, int flags)
 {
 	struct iattr iattr;
 
diff --git a/fs/jffs2/os-linux.h b/fs/jffs2/os-linux.h
index 00bae7c..65c6c43 100644
--- a/fs/jffs2/os-linux.h
+++ b/fs/jffs2/os-linux.h
@@ -172,7 +172,7 @@
 int jffs2_do_setattr (struct inode *, struct iattr *);
 struct inode *jffs2_iget(struct super_block *, unsigned long);
 void jffs2_evict_inode (struct inode *);
-void jffs2_dirty_inode(struct inode *inode);
+void jffs2_dirty_inode(struct inode *inode, int flags);
 struct inode *jffs2_new_inode (struct inode *dir_i, int mode,
 			       struct jffs2_raw_inode *ri);
 int jffs2_statfs (struct dentry *, struct kstatfs *);
diff --git a/fs/jfs/inode.c b/fs/jfs/inode.c
index eddbb37..1096559 100644
--- a/fs/jfs/inode.c
+++ b/fs/jfs/inode.c
@@ -173,7 +173,7 @@
 	dquot_drop(inode);
 }
 
-void jfs_dirty_inode(struct inode *inode)
+void jfs_dirty_inode(struct inode *inode, int flags)
 {
 	static int noisy = 5;
 
diff --git a/fs/jfs/jfs_inode.h b/fs/jfs/jfs_inode.h
index 155e91e..ec2fb8b 100644
--- a/fs/jfs/jfs_inode.h
+++ b/fs/jfs/jfs_inode.h
@@ -28,7 +28,7 @@
 extern int jfs_commit_inode(struct inode *, int);
 extern int jfs_write_inode(struct inode *, struct writeback_control *);
 extern void jfs_evict_inode(struct inode *);
-extern void jfs_dirty_inode(struct inode *);
+extern void jfs_dirty_inode(struct inode *, int);
 extern void jfs_truncate(struct inode *);
 extern void jfs_truncate_nolock(struct inode *, loff_t);
 extern void jfs_free_zero_link(struct inode *);
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 587f184..b954878 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -917,7 +917,7 @@
  * construction. This function can be called both as a single operation
  * and as a part of indivisible file operations.
  */
-void nilfs_dirty_inode(struct inode *inode)
+void nilfs_dirty_inode(struct inode *inode, int flags)
 {
 	struct nilfs_transaction_info ti;
 	struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
diff --git a/fs/nilfs2/nilfs.h b/fs/nilfs2/nilfs.h
index a9c6a53..f02b9ad 100644
--- a/fs/nilfs2/nilfs.h
+++ b/fs/nilfs2/nilfs.h
@@ -269,7 +269,7 @@
 extern int nilfs_inode_dirty(struct inode *);
 int nilfs_set_file_dirty(struct inode *inode, unsigned nr_dirty);
 extern int nilfs_mark_inode_dirty(struct inode *);
-extern void nilfs_dirty_inode(struct inode *);
+extern void nilfs_dirty_inode(struct inode *, int flags);
 int nilfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 		 __u64 start, __u64 len);
 
diff --git a/fs/reiserfs/super.c b/fs/reiserfs/super.c
index b216ff6..aa91089 100644
--- a/fs/reiserfs/super.c
+++ b/fs/reiserfs/super.c
@@ -568,7 +568,7 @@
 }
 
 /* we don't mark inodes dirty, we just log them */
-static void reiserfs_dirty_inode(struct inode *inode)
+static void reiserfs_dirty_inode(struct inode *inode, int flags)
 {
 	struct reiserfs_transaction_handle th;
 
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 6db0bdaa..1ab0d22 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -382,7 +382,7 @@
 	end_writeback(inode);
 }
 
-static void ubifs_dirty_inode(struct inode *inode)
+static void ubifs_dirty_inode(struct inode *inode, int flags)
 {
 	struct ubifs_inode *ui = ubifs_inode(inode);
 
diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c
index 98b9c91..1e3a7ce 100644
--- a/fs/xfs/linux-2.6/xfs_super.c
+++ b/fs/xfs/linux-2.6/xfs_super.c
@@ -925,7 +925,8 @@
  */
 STATIC void
 xfs_fs_dirty_inode(
-	struct inode	*inode)
+	struct inode	*inode,
+	int		flags)
 {
 	barrier();
 	XFS_I(inode)->i_update_core = 1;
diff --git a/include/linux/ext3_fs.h b/include/linux/ext3_fs.h
index 85c1d30..5e06acf 100644
--- a/include/linux/ext3_fs.h
+++ b/include/linux/ext3_fs.h
@@ -909,7 +909,7 @@
 extern void ext3_evict_inode (struct inode *);
 extern int  ext3_sync_inode (handle_t *, struct inode *);
 extern void ext3_discard_reservation (struct inode *);
-extern void ext3_dirty_inode(struct inode *);
+extern void ext3_dirty_inode(struct inode *, int);
 extern int ext3_change_inode_journal_flag(struct inode *, int);
 extern int ext3_get_inode_loc(struct inode *, struct ext3_iloc *);
 extern int ext3_can_truncate(struct inode *inode);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 2416093..573028d 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1618,7 +1618,7 @@
    	struct inode *(*alloc_inode)(struct super_block *sb);
 	void (*destroy_inode)(struct inode *);
 
-   	void (*dirty_inode) (struct inode *);
+   	void (*dirty_inode) (struct inode *, int flags);
 	int (*write_inode) (struct inode *, struct writeback_control *wbc);
 	int (*drop_inode) (struct inode *);
 	void (*evict_inode) (struct inode *);