1 files changed, 24 insertions, 5 deletions

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 77a0bc4e261a..555752907dc3 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -23,6 +23,7 @@
 #include <linux/backing-dev.h>
 #include <linux/blkdev.h>
 #include <linux/mpage.h>
+#include <linux/rmap.h>
 #include <linux/percpu.h>
 #include <linux/notifier.h>
 #include <linux/smp.h>
@@ -243,6 +244,16 @@ static void balance_dirty_pages(struct address_space *mapping)
                 pdflush_operation(background_writeout, 0);
 }
 
+void set_page_dirty_balance(struct page *page)
+{
+        if (set_page_dirty(page)) {
+                struct address_space *mapping = page_mapping(page);
+
+                if (mapping)
+                        balance_dirty_pages_ratelimited(mapping);
+        }
+}
+
 /**
  * balance_dirty_pages_ratelimited_nr - balance dirty memory state
  * @mapping: address_space which was dirtied
@@ -550,7 +561,7 @@ int do_writepages(struct address_space *mapping, struct writeback_control *wbc)
                 return 0;
         wbc->for_writepages = 1;
         if (mapping->a_ops->writepages)
-                ret =  mapping->a_ops->writepages(mapping, wbc);
+                ret = mapping->a_ops->writepages(mapping, wbc);
         else
                 ret = generic_writepages(mapping, wbc);
         wbc->for_writepages = 0;
@@ -690,7 +701,7 @@ int set_page_dirty_lock(struct page *page)
 {
         int ret;
 
-        lock_page(page);
+        lock_page_nosync(page);
         ret = set_page_dirty(page);
         unlock_page(page);
         return ret;
@@ -712,9 +723,15 @@ int test_clear_page_dirty(struct page *page)
                         radix_tree_tag_clear(&mapping->page_tree,
                                                 page_index(page),
                                                 PAGECACHE_TAG_DIRTY);
-                        if (mapping_cap_account_dirty(mapping))
-                                __dec_zone_page_state(page, NR_FILE_DIRTY);
                         write_unlock_irqrestore(&mapping->tree_lock, flags);
+                        /*
+                         * We can continue to use `mapping' here because the
+                         * page is locked, which pins the address_space
+                         */
+                        if (mapping_cap_account_dirty(mapping)) {
+                                page_mkclean(page);
+                                dec_zone_page_state(page, NR_FILE_DIRTY);
+                        }
                         return 1;
                 }
                 write_unlock_irqrestore(&mapping->tree_lock, flags);
@@ -744,8 +761,10 @@ int clear_page_dirty_for_io(struct page *page)
 
         if (mapping) {
                 if (TestClearPageDirty(page)) {
-                        if (mapping_cap_account_dirty(mapping))
+                        if (mapping_cap_account_dirty(mapping)) {
+                                page_mkclean(page);
                                 dec_zone_page_state(page, NR_FILE_DIRTY);
+                        }
                         return 1;
                 }
                 return 0;