Upgrade to 4.4.50-rt62
[kvmfornfv.git] / kernel / fs / btrfs / inode.c
index 4bc9dbf..3cff652 100644 (file)
@@ -8691,9 +8691,14 @@ static void btrfs_invalidatepage(struct page *page, unsigned int offset,
         *    So even we call qgroup_free_data(), it won't decrease reserved
         *    space.
         * 2) Not written to disk
-        *    This means the reserved space should be freed here.
+        *    This means the reserved space should be freed here. However,
+        *    if a truncate invalidates the page (by clearing PageDirty)
+        *    and the page is accounted for while allocating extent
+        *    in btrfs_check_data_free_space() we let delayed_ref to
+        *    free the entire extent.
         */
-       btrfs_qgroup_free_data(inode, page_start, PAGE_CACHE_SIZE);
+       if (PageDirty(page))
+               btrfs_qgroup_free_data(inode, page_start, PAGE_SIZE);
        if (!inode_evicting) {
                clear_extent_bit(tree, page_start, page_end,
                                 EXTENT_LOCKED | EXTENT_DIRTY |