Merge branch 'for-2.6.39/stack-plug' into for-2.6.39/core

Conflicts:
	block/blk-core.c
	block/blk-flush.c
	drivers/md/raid1.c
	drivers/md/raid10.c
	drivers/md/raid5.c
	fs/nilfs2/btnode.c
	fs/nilfs2/mdt.c

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

1 files changed, 6 insertions, 12 deletions

diff --git a/mm/readahead.c b/mm/readahead.c
index 77506a291a2..2c0cc489e28 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -109,9 +109,12 @@ EXPORT_SYMBOL(read_cache_pages);
 static int read_pages(struct address_space *mapping, struct file *filp,
 		struct list_head *pages, unsigned nr_pages)
 {
+	struct blk_plug plug;
 	unsigned page_idx;
 	int ret;
 
+	blk_start_plug(&plug);
+
 	if (mapping->a_ops->readpages) {
 		ret = mapping->a_ops->readpages(filp, mapping, pages, nr_pages);
 		/* Clean up the remaining pages */
@@ -129,7 +132,10 @@ static int read_pages(struct address_space *mapping, struct file *filp,
 		page_cache_release(page);
 	}
 	ret = 0;
+
 out:
+	blk_finish_plug(&plug);
+
 	return ret;
 }
 
@@ -554,17 +560,5 @@ page_cache_async_readahead(struct address_space *mapping,
 
 	/* do read-ahead */
 	ondemand_readahead(mapping, ra, filp, true, offset, req_size);
-
-#ifdef CONFIG_BLOCK
-	/*
-	 * Normally the current page is !uptodate and lock_page() will be
-	 * immediately called to implicitly unplug the device. However this
-	 * is not always true for RAID conifgurations, where data arrives
-	 * not strictly in their submission order. In this case we need to
-	 * explicitly kick off the IO.
-	 */
-	if (PageUptodate(page))
-		blk_run_backing_dev(mapping->backing_dev_info, NULL);
-#endif
 }
 EXPORT_SYMBOL_GPL(page_cache_async_readahead);