Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block

* 'for-linus' of git://git.kernel.dk/linux-2.6-block: (27 commits)
  block: make blk_init_free_list and elevator_init idempotent
  block: avoid unconditionally freeing previously allocated request_queue
  pipe: change /proc/sys/fs/pipe-max-pages to byte sized interface
  pipe: change the privilege required for growing a pipe beyond system max
  pipe: adjust minimum pipe size to 1 page
  block: disable preemption before using sched_clock()
  cciss: call BUG() earlier
  Preparing 8.3.8rc2
  drbd: Reduce verbosity
  drbd: use drbd specific ratelimit instead of global printk_ratelimit
  drbd: fix hang on local read errors while disconnected
  drbd: Removed the now empty w_io_error() function
  drbd: removed duplicated #includes
  drbd: improve usage of MSG_MORE
  drbd: need to set socket bufsize early to take effect
  drbd: improve network latency, TCP_QUICKACK
  drbd: Revert "drbd: Create new current UUID as late as possible"
  brd: support discard
  Revert "writeback: fix WB_SYNC_NONE writeback from umount"
  Revert "writeback: ensure that WB_SYNC_NONE writeback with sb pinned is sync"
  ...

1 files changed, 16 insertions, 48 deletions

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index ea8592b90696..1d1088f48bc2 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -45,7 +45,6 @@ struct wb_writeback_args {
 	unsigned int for_kupdate:1;
 	unsigned int range_cyclic:1;
 	unsigned int for_background:1;
-	unsigned int sb_pinned:1;
 };
 
 /*
@@ -193,8 +192,7 @@ static void bdi_wait_on_work_clear(struct bdi_work *work)
 }
 
 static void bdi_alloc_queue_work(struct backing_dev_info *bdi,
-				 struct wb_writeback_args *args,
-				 int wait)
+				 struct wb_writeback_args *args)
 {
 	struct bdi_work *work;
 
@@ -206,8 +204,6 @@ static void bdi_alloc_queue_work(struct backing_dev_info *bdi,
 	if (work) {
 		bdi_work_init(work, args);
 		bdi_queue_work(bdi, work);
-		if (wait)
-			bdi_wait_on_work_clear(work);
 	} else {
 		struct bdi_writeback *wb = &bdi->wb;
 
@@ -234,11 +230,6 @@ static void bdi_sync_writeback(struct backing_dev_info *bdi,
 		.sync_mode	= WB_SYNC_ALL,
 		.nr_pages	= LONG_MAX,
 		.range_cyclic	= 0,
-		/*
-		 * Setting sb_pinned is not necessary for WB_SYNC_ALL, but
-		 * lets make it explicitly clear.
-		 */
-		.sb_pinned	= 1,
 	};
 	struct bdi_work work;
 
@@ -254,23 +245,21 @@ static void bdi_sync_writeback(struct backing_dev_info *bdi,
  * @bdi: the backing device to write from
  * @sb: write inodes from this super_block
  * @nr_pages: the number of pages to write
- * @sb_locked: caller already holds sb umount sem.
  *
  * Description:
  *   This does WB_SYNC_NONE opportunistic writeback. The IO is only
  *   started when this function returns, we make no guarentees on
- *   completion. Caller specifies whether sb umount sem is held already or not.
+ *   completion. Caller need not hold sb s_umount semaphore.
  *
  */
 void bdi_start_writeback(struct backing_dev_info *bdi, struct super_block *sb,
-			 long nr_pages, int sb_locked)
+			 long nr_pages)
 {
 	struct wb_writeback_args args = {
 		.sb		= sb,
 		.sync_mode	= WB_SYNC_NONE,
 		.nr_pages	= nr_pages,
 		.range_cyclic	= 1,
-		.sb_pinned	= sb_locked,
 	};
 
 	/*
@@ -282,7 +271,7 @@ void bdi_start_writeback(struct backing_dev_info *bdi, struct super_block *sb,
 		args.for_background = 1;
 	}
 
-	bdi_alloc_queue_work(bdi, &args, sb_locked);
+	bdi_alloc_queue_work(bdi, &args);
 }
 
 /*
@@ -595,7 +584,7 @@ static enum sb_pin_state pin_sb_for_writeback(struct writeback_control *wbc,
 	/*
 	 * Caller must already hold the ref for this
 	 */
-	if (wbc->sync_mode == WB_SYNC_ALL || wbc->sb_pinned) {
+	if (wbc->sync_mode == WB_SYNC_ALL) {
 		WARN_ON(!rwsem_is_locked(&sb->s_umount));
 		return SB_NOT_PINNED;
 	}
@@ -769,7 +758,6 @@ static long wb_writeback(struct bdi_writeback *wb,
 		.for_kupdate		= args->for_kupdate,
 		.for_background		= args->for_background,
 		.range_cyclic		= args->range_cyclic,
-		.sb_pinned		= args->sb_pinned,
 	};
 	unsigned long oldest_jif;
 	long wrote = 0;
@@ -912,7 +900,6 @@ long wb_do_writeback(struct bdi_writeback *wb, int force_wait)
 
 	while ((work = get_next_work_item(bdi, wb)) != NULL) {
 		struct wb_writeback_args args = work->args;
-		int post_clear;
 
 		/*
 		 * Override sync mode, in case we must wait for completion
@@ -920,13 +907,11 @@ long wb_do_writeback(struct bdi_writeback *wb, int force_wait)
 		if (force_wait)
 			work->args.sync_mode = args.sync_mode = WB_SYNC_ALL;
 
-		post_clear = WB_SYNC_ALL || args.sb_pinned;
-
 		/*
 		 * If this isn't a data integrity operation, just notify
 		 * that we have seen this work and we are now starting it.
 		 */
-		if (!post_clear)
+		if (args.sync_mode == WB_SYNC_NONE)
 			wb_clear_pending(wb, work);
 
 		wrote += wb_writeback(wb, &args);
@@ -935,7 +920,7 @@ long wb_do_writeback(struct bdi_writeback *wb, int force_wait)
 		 * This is a data integrity writeback, so only do the
 		 * notification when we have completed the work.
 		 */
-		if (post_clear)
+		if (args.sync_mode == WB_SYNC_ALL)
 			wb_clear_pending(wb, work);
 	}
 
@@ -1011,7 +996,7 @@ static void bdi_writeback_all(struct super_block *sb, long nr_pages)
 		if (!bdi_has_dirty_io(bdi))
 			continue;
 
-		bdi_alloc_queue_work(bdi, &args, 0);
+		bdi_alloc_queue_work(bdi, &args);
 	}
 
 	rcu_read_unlock();
@@ -1220,18 +1205,6 @@ static void wait_sb_inodes(struct super_block *sb)
 	iput(old_inode);
 }
 
-static void __writeback_inodes_sb(struct super_block *sb, int sb_locked)
-{
-	unsigned long nr_dirty = global_page_state(NR_FILE_DIRTY);
-	unsigned long nr_unstable = global_page_state(NR_UNSTABLE_NFS);
-	long nr_to_write;
-
-	nr_to_write = nr_dirty + nr_unstable +
-			(inodes_stat.nr_inodes - inodes_stat.nr_unused);
-
-	bdi_start_writeback(sb->s_bdi, sb, nr_to_write, sb_locked);
-}
-
 /**
  * writeback_inodes_sb	-	writeback dirty inodes from given super_block
  * @sb: the superblock
@@ -1243,21 +1216,16 @@ static void __writeback_inodes_sb(struct super_block *sb, int sb_locked)
  */
 void writeback_inodes_sb(struct super_block *sb)
 {
-	__writeback_inodes_sb(sb, 0);
-}
-EXPORT_SYMBOL(writeback_inodes_sb);
+	unsigned long nr_dirty = global_page_state(NR_FILE_DIRTY);
+	unsigned long nr_unstable = global_page_state(NR_UNSTABLE_NFS);
+	long nr_to_write;
 
-/**
- * writeback_inodes_sb_locked	- writeback dirty inodes from given super_block
- * @sb: the superblock
- *
- * Like writeback_inodes_sb(), except the caller already holds the
- * sb umount sem.
- */
-void writeback_inodes_sb_locked(struct super_block *sb)
-{
-	__writeback_inodes_sb(sb, 1);
+	nr_to_write = nr_dirty + nr_unstable +
+			(inodes_stat.nr_inodes - inodes_stat.nr_unused);
+
+	bdi_start_writeback(sb->s_bdi, sb, nr_to_write);
 }
+EXPORT_SYMBOL(writeback_inodes_sb);
 
 /**
  * writeback_inodes_sb_if_idle	-	start writeback if none underway