[PATCH] Fix XFS after clear_page_dirty() removal

XFS appears to call clear_page_dirty to get the mapping tree dirty tag
set correctly at the same time the page dirty flag is cleared.  I note
that this can be done by set_page_writeback() if we clear the dirty flag
on the page first when we are writing back the entire page.

Hence it seems to me that the XFS call to clear_page_dirty() could
easily be substituted by clear_page_dirty_for_io() followed by a call to
set_page_writeback() to get the mapping tree tags set correctly after
the page has been marked clean.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index b56eb75..7b54461 100644 (file)
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -341,9 +341,9 @@ xfs_start_page_writeback(
 {
        ASSERT(PageLocked(page));
        ASSERT(!PageWriteback(page));
-       set_page_writeback(page);
        if (clear_dirty)
-               clear_page_dirty(page);
+               clear_page_dirty_for_io(page);
+       set_page_writeback(page);
        unlock_page(page);
        if (!buffers) {
                end_page_writeback(page);