Re: Review: Clear unwritten flag on during partial page truncation

[Lachlan McIlroy <lachlan@xxxxxxx>]

@@ -41,6 +41,8 @@
 #include <linux/pagevec.h>
 #include <linux/writeback.h>

+STATIC void xfs_vm_invalidatepage(struct page *, unsigned long);
+
 STATIC void
 xfs_count_page_state(
        struct page             *page,
@@ -1061,7 +1063,7 @@ error:
         */
        if (err != -EAGAIN) {
                if (!unmapped)
-                       block_invalidatepage(page, 0);
+                       xfs_vm_invalidatepage(page, 0);

We pass in an offset of zero here...


@@ -1458,6 +1468,32 @@ xfs_vm_invalidatepage(
 {
        xfs_page_trace(XFS_INVALIDPAGE_ENTER,
                        page->mapping->host, page, offset);
+
+       /*
+        * Need to clear private flags from buffers on partial
+        * page truncations ourselves. Same inner loop as
+        * block_invalidatepage() is used.
+        */
+       if (offset && page_has_buffers(page)) {

And only do this code for non-zero offsets.  Are you sure this is correct?