1 files changed, 17 insertions, 10 deletions

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 8bef063125b1..69b5fbabc8bd 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -158,37 +158,37 @@ static void update_completion_period(void)
 }
 
 int dirty_background_ratio_handler(struct ctl_table *table, int write,
-		struct file *filp, void __user *buffer, size_t *lenp,
+		void __user *buffer, size_t *lenp,
 		loff_t *ppos)
 {
 	int ret;
 
-	ret = proc_dointvec_minmax(table, write, filp, buffer, lenp, ppos);
+	ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
 	if (ret == 0 && write)
 		dirty_background_bytes = 0;
 	return ret;
 }
 
 int dirty_background_bytes_handler(struct ctl_table *table, int write,
-		struct file *filp, void __user *buffer, size_t *lenp,
+		void __user *buffer, size_t *lenp,
 		loff_t *ppos)
 {
 	int ret;
 
-	ret = proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos);
+	ret = proc_doulongvec_minmax(table, write, buffer, lenp, ppos);
 	if (ret == 0 && write)
 		dirty_background_ratio = 0;
 	return ret;
 }
 
 int dirty_ratio_handler(struct ctl_table *table, int write,
-		struct file *filp, void __user *buffer, size_t *lenp,
+		void __user *buffer, size_t *lenp,
 		loff_t *ppos)
 {
 	int old_ratio = vm_dirty_ratio;
 	int ret;
 
-	ret = proc_dointvec_minmax(table, write, filp, buffer, lenp, ppos);
+	ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
 	if (ret == 0 && write && vm_dirty_ratio != old_ratio) {
 		update_completion_period();
 		vm_dirty_bytes = 0;
@@ -198,13 +198,13 @@ int dirty_ratio_handler(struct ctl_table *table, int write,
 
 
 int dirty_bytes_handler(struct ctl_table *table, int write,
-		struct file *filp, void __user *buffer, size_t *lenp,
+		void __user *buffer, size_t *lenp,
 		loff_t *ppos)
 {
 	unsigned long old_bytes = vm_dirty_bytes;
 	int ret;
 
-	ret = proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos);
+	ret = proc_doulongvec_minmax(table, write, buffer, lenp, ppos);
 	if (ret == 0 && write && vm_dirty_bytes != old_bytes) {
 		update_completion_period();
 		vm_dirty_ratio = 0;
@@ -690,9 +690,9 @@ static DEFINE_TIMER(laptop_mode_wb_timer, laptop_timer_fn, 0, 0);
  * sysctl handler for /proc/sys/vm/dirty_writeback_centisecs
  */
 int dirty_writeback_centisecs_handler(ctl_table *table, int write,
-	struct file *file, void __user *buffer, size_t *length, loff_t *ppos)
+	void __user *buffer, size_t *length, loff_t *ppos)
 {
-	proc_dointvec(table, write, file, buffer, length, ppos);
+	proc_dointvec(table, write, buffer, length, ppos);
 	return 0;
 }
 
@@ -1153,6 +1153,13 @@ int redirty_page_for_writepage(struct writeback_control *wbc, struct page *page)
 EXPORT_SYMBOL(redirty_page_for_writepage);
 
 /*
+ * Dirty a page.
+ *
+ * For pages with a mapping this should be done under the page lock
+ * for the benefit of asynchronous memory errors who prefer a consistent
+ * dirty state. This rule can be broken in some special cases,
+ * but should be better not to.
+ *
  * If the mapping doesn't provide a set_page_dirty a_op, then
  * just fall through and assume that it wants buffer_heads.
  */