Revert "writeback: do not sync data dirtied after sync start"
This reverts commit c4a391b53a72d2df4ee97f96f78c1d5971b47489. Dave
Chinner <david@fromorbit.com> has reported the commit may cause some
inodes to be left out from sync(2). This is because we can call
redirty_tail() for some inode (which sets i_dirtied_when to current time)
after sync(2) has started or similarly requeue_inode() can set
i_dirtied_when to current time if writeback had to skip some pages. The
real problem is in the functions clobbering i_dirtied_when but fixing
that isn't trivial so revert is a safer choice for now.
CC: stable@vger.kernel.org # >= 3.13
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/sync.c b/fs/sync.c
index e8ba024..b28d1dd 100644
--- a/fs/sync.c
+++ b/fs/sync.c
@@ -27,11 +27,10 @@
* wait == 1 case since in that case write_inode() functions do
* sync_dirty_buffer() and thus effectively write one block at a time.
*/
-static int __sync_filesystem(struct super_block *sb, int wait,
- unsigned long start)
+static int __sync_filesystem(struct super_block *sb, int wait)
{
if (wait)
- sync_inodes_sb(sb, start);
+ sync_inodes_sb(sb);
else
writeback_inodes_sb(sb, WB_REASON_SYNC);
@@ -48,7 +47,6 @@
int sync_filesystem(struct super_block *sb)
{
int ret;
- unsigned long start = jiffies;
/*
* We need to be protected against the filesystem going from
@@ -62,17 +60,17 @@
if (sb->s_flags & MS_RDONLY)
return 0;
- ret = __sync_filesystem(sb, 0, start);
+ ret = __sync_filesystem(sb, 0);
if (ret < 0)
return ret;
- return __sync_filesystem(sb, 1, start);
+ return __sync_filesystem(sb, 1);
}
EXPORT_SYMBOL_GPL(sync_filesystem);
static void sync_inodes_one_sb(struct super_block *sb, void *arg)
{
if (!(sb->s_flags & MS_RDONLY))
- sync_inodes_sb(sb, *((unsigned long *)arg));
+ sync_inodes_sb(sb);
}
static void sync_fs_one_sb(struct super_block *sb, void *arg)
@@ -104,10 +102,9 @@
SYSCALL_DEFINE0(sync)
{
int nowait = 0, wait = 1;
- unsigned long start = jiffies;
wakeup_flusher_threads(0, WB_REASON_SYNC);
- iterate_supers(sync_inodes_one_sb, &start);
+ iterate_supers(sync_inodes_one_sb, NULL);
iterate_supers(sync_fs_one_sb, &nowait);
iterate_supers(sync_fs_one_sb, &wait);
iterate_bdevs(fdatawrite_one_bdev, NULL);