Merge branch 'akpm' (patches from Andrew Morton)

Merge first patch-bomb from Andrew Morton:
 "Quite a lot of other stuff is banked up awaiting further
  next->mainline merging, but this batch contains:

   - Lots of random misc patches
   - OCFS2
   - Most of MM
   - backlight updates
   - lib/ updates
   - printk updates
   - checkpatch updates
   - epoll tweaking
   - rtc updates
   - hfs
   - hfsplus
   - documentation
   - procfs
   - update gcov to gcc-4.7 format
   - IPC"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (269 commits)
  ipc, msg: fix message length check for negative values
  ipc/util.c: remove unnecessary work pending test
  devpts: plug the memory leak in kill_sb
  ./Makefile: export initial ramdisk compression config option
  init/Kconfig: add option to disable kernel compression
  drivers: w1: make w1_slave::flags long to avoid memory corruption
  drivers/w1/masters/ds1wm.cuse dev_get_platdata()
  drivers/memstick/core/ms_block.c: fix unreachable state in h_msb_read_page()
  drivers/memstick/core/mspro_block.c: fix attributes array allocation
  drivers/pps/clients/pps-gpio.c: remove redundant of_match_ptr
  kernel/panic.c: reduce 1 byte usage for print tainted buffer
  gcov: reuse kbasename helper
  kernel/gcov/fs.c: use pr_warn()
  kernel/module.c: use pr_foo()
  gcov: compile specific gcov implementation based on gcc version
  gcov: add support for gcc 4.7 gcov format
  gcov: move gcov structs definitions to a gcc version specific file
  kernel/taskstats.c: return -ENOMEM when alloc memory fails in add_del_listener()
  kernel/taskstats.c: add nla_nest_cancel() for failure processing between nla_nest_start() and nla_nest_end()
  kernel/sysctl_binary.c: use scnprintf() instead of snprintf()
  ...

1 files changed, 22 insertions, 11 deletions

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 09c11329a17c..1f4a10ece2f1 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -40,13 +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 */
@@ -247,10 +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++;
@@ -734,6 +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);
@@ -792,12 +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 (;;) {
@@ -831,10 +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))
@@ -1346,18 +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,