X-Git-Url: http://pileus.org/git/?a=blobdiff_plain;f=fs%2Ffs-writeback.c;h=1f4a10ece2f1249d5ae9991bfdde4874019b3462;hb=31e20bad8d5871c6f8673c28ea26ab7a0e520086;hp=9f4935b8f2087eb44475bf7fb8aab20f44889e86;hpb=a72e25f78134cc0c1ef2adc99d6c3680ebd80e35;p=~andy%2Flinux

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 9f4935b8f20..1f4a10ece2f 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -26,6 +26,7 @@
 #include <linux/blkdev.h>
 #include <linux/backing-dev.h>
 #include <linux/tracepoint.h>
+#include <linux/device.h>
 #include "internal.h"
 
 /*
@@ -39,13 +40,18 @@
 struct wb_writeback_work {
 	long nr_pages;
 	struct super_block *sb;
-	unsigned long *older_than_this;
+	/*
+	 * Write only inodes dirtied before this time. Don't forget to set
+	 * older_than_this_is_set when you set this.
+	 */
+	unsigned long older_than_this;
 	enum writeback_sync_modes sync_mode;
 	unsigned int tagged_writepages:1;
 	unsigned int for_kupdate:1;
 	unsigned int range_cyclic:1;
 	unsigned int for_background:1;
 	unsigned int for_sync:1;	/* sync(2) WB_SYNC_ALL writeback */
+	unsigned int older_than_this_is_set:1;
 	enum wb_reason reason;		/* why was writeback initiated? */
 
 	struct list_head list;		/* pending work list */
@@ -246,10 +252,10 @@ static int move_expired_inodes(struct list_head *delaying_queue,
 	int do_sb_sort = 0;
 	int moved = 0;
 
+	WARN_ON_ONCE(!work->older_than_this_is_set);
 	while (!list_empty(delaying_queue)) {
 		inode = wb_inode(delaying_queue->prev);
-		if (work->older_than_this &&
-		    inode_dirtied_after(inode, *work->older_than_this))
+		if (inode_dirtied_after(inode, work->older_than_this))
 			break;
 		list_move(&inode->i_wb_list, &tmp);
 		moved++;
@@ -733,6 +739,8 @@ static long writeback_inodes_wb(struct bdi_writeback *wb, long nr_pages,
 		.sync_mode	= WB_SYNC_NONE,
 		.range_cyclic	= 1,
 		.reason		= reason,
+		.older_than_this = jiffies,
+		.older_than_this_is_set = 1,
 	};
 
 	spin_lock(&wb->list_lock);
@@ -791,12 +799,13 @@ static long wb_writeback(struct bdi_writeback *wb,
 {
 	unsigned long wb_start = jiffies;
 	long nr_pages = work->nr_pages;
-	unsigned long oldest_jif;
 	struct inode *inode;
 	long progress;
 
-	oldest_jif = jiffies;
-	work->older_than_this = &oldest_jif;
+	if (!work->older_than_this_is_set) {
+		work->older_than_this = jiffies;
+		work->older_than_this_is_set = 1;
+	}
 
 	spin_lock(&wb->list_lock);
 	for (;;) {
@@ -830,10 +839,10 @@ static long wb_writeback(struct bdi_writeback *wb,
 		 * safe.
 		 */
 		if (work->for_kupdate) {
-			oldest_jif = jiffies -
+			work->older_than_this = jiffies -
 				msecs_to_jiffies(dirty_expire_interval * 10);
 		} else if (work->for_background)
-			oldest_jif = jiffies;
+			work->older_than_this = jiffies;
 
 		trace_writeback_start(wb->bdi, work);
 		if (list_empty(&wb->b_io))
@@ -1345,18 +1354,21 @@ EXPORT_SYMBOL(try_to_writeback_inodes_sb);
 
 /**
  * sync_inodes_sb	-	sync sb inode pages
- * @sb: the superblock
+ * @sb:			the superblock
+ * @older_than_this:	timestamp
  *
  * This function writes and waits on any dirty inode belonging to this
- * super_block.
+ * superblock that has been dirtied before given timestamp.
  */
-void sync_inodes_sb(struct super_block *sb)
+void sync_inodes_sb(struct super_block *sb, unsigned long older_than_this)
 {
 	DECLARE_COMPLETION_ONSTACK(done);
 	struct wb_writeback_work work = {
 		.sb		= sb,
 		.sync_mode	= WB_SYNC_ALL,
 		.nr_pages	= LONG_MAX,
+		.older_than_this = older_than_this,
+		.older_than_this_is_set = 1,
 		.range_cyclic	= 0,
 		.done		= &done,
 		.reason		= WB_REASON_SYNC,