hugetlb: chg cannot become less than 0

[firefly-linux-kernel-4.4.55.git] / mm / page-writeback.c

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 40ca7cdb653ec280d8115ff3d8b35cb6ee57669e..6aa92b03c74704f328d157d8e6e84c340e42d6c5 100644 (file)
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -1197,6 +1197,20 @@ int __set_page_dirty_no_writeback(struct page *page)
        return 0;
 }
 
+/*
+ * Helper function for set_page_dirty family.
+ * NOTE: This relies on being atomic wrt interrupts.
+ */
+void account_page_dirtied(struct page *page, struct address_space *mapping)
+{
+       if (mapping_cap_account_dirty(mapping)) {
+               __inc_zone_page_state(page, NR_FILE_DIRTY);
+               __inc_bdi_stat(mapping->backing_dev_info, BDI_RECLAIMABLE);
+               task_dirty_inc(current);
+               task_io_account_write(PAGE_CACHE_SIZE);
+       }
+}
+
 /*
  * For address_spaces which do not use buffers.  Just tag the page as dirty in
  * its radix tree.
@@ -1226,13 +1240,7 @@ int __set_page_dirty_nobuffers(struct page *page)
                if (mapping2) { /* Race with truncate? */
                        BUG_ON(mapping2 != mapping);
                        WARN_ON_ONCE(!PagePrivate(page) && !PageUptodate(page));
-                       if (mapping_cap_account_dirty(mapping)) {
-                               __inc_zone_page_state(page, NR_FILE_DIRTY);
-                               __inc_bdi_stat(mapping->backing_dev_info,
-                                               BDI_RECLAIMABLE);
-                               task_dirty_inc(current);
-                               task_io_account_write(PAGE_CACHE_SIZE);
-                       }
+                       account_page_dirtied(page, mapping);
                        radix_tree_tag_set(&mapping->page_tree,
                                page_index(page), PAGECACHE_TAG_DIRTY);
                }