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>

1 files changed, 1 insertions, 4 deletions

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 34591ee804b5..0f015a0468de 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -1007,9 +1007,6 @@ static noinline void block_dump___mark_inode_dirty(struct inode *inode)
  * 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 @@ void __mark_inode_dirty(struct inode *inode, int flags)
          */
         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);
         }
 
         /*