[PATCH] Fix up CIFS for "test_clear_page_dirty()" removal

Fix up CIFS for "test_clear_page_dirty()" removal

This also adds he required page "writeback" flag handling, that cifs
hasn't been doing and that the page dirty flag changes made obvious.

Acked-by: Steve French <smfltc@us.ibm.com>
Acked-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>

diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 2436ed8fc8400e2d86b4e5bbb569b122ac013e34..14fd25122fdd91a718a9c539fcb87c543f55389a 100644 (file)
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1244,14 +1244,21 @@ retry:
                                wait_on_page_writeback(page);
 
                        if (PageWriteback(page) ||
-                                       !test_clear_page_dirty(page)) {
+                                       !clear_page_dirty_for_io(page)) {
                                unlock_page(page);
                                break;
                        }
 
+                       /*
+                        * This actually clears the dirty bit in the radix tree.
+                        * See cifs_writepage() for more commentary.
+                        */
+                       set_page_writeback(page);
+
                        if (page_offset(page) >= mapping->host->i_size) {
                                done = 1;
                                unlock_page(page);
+                               end_page_writeback(page);
                                break;
                        }
 
@@ -1315,6 +1322,7 @@ retry:
                                        SetPageError(page);
                                kunmap(page);
                                unlock_page(page);
+                               end_page_writeback(page);
                                page_cache_release(page);
                        }
                        if ((wbc->nr_to_write -= n_iov) <= 0)
@@ -1351,11 +1359,23 @@ static int cifs_writepage(struct page* page, struct writeback_control *wbc)
         if (!PageUptodate(page)) {
                cFYI(1, ("ppw - page not up to date"));
        }
-       
+
+       /*
+        * Set the "writeback" flag, and clear "dirty" in the radix tree.
+        *
+        * A writepage() implementation always needs to do either this,
+        * or re-dirty the page with "redirty_page_for_writepage()" in
+        * the case of a failure.
+        *
+        * Just unlocking the page will cause the radix tree tag-bits
+        * to fail to update with the state of the page correctly.
+        */
+       set_page_writeback(page);               
        rc = cifs_partialpagewrite(page, 0, PAGE_CACHE_SIZE);
        SetPageUptodate(page); /* BB add check for error and Clearuptodate? */
        unlock_page(page);
-       page_cache_release(page);       
+       end_page_writeback(page);
+       page_cache_release(page);
        FreeXid(xid);
        return rc;
 }