Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial

[kernel/kernel-generic.git] / mm / bounce.c

diff --git a/mm/bounce.c b/mm/bounce.c
index 5f89017..a5c2ec3 100644 (file)
--- a/mm/bounce.c
+++ b/mm/bounce.c
@@ -181,32 +181,13 @@ static void bounce_end_io_read_isa(struct bio *bio, int err)
 #ifdef CONFIG_NEED_BOUNCE_POOL
 static int must_snapshot_stable_pages(struct request_queue *q, struct bio *bio)
 {
-       struct page *page;
-       struct backing_dev_info *bdi;
-       struct address_space *mapping;
-       struct bio_vec *from;
-       int i;
-
        if (bio_data_dir(bio) != WRITE)
                return 0;
 
        if (!bdi_cap_stable_pages_required(&q->backing_dev_info))
                return 0;
 
-       /*
-        * Based on the first page that has a valid mapping, decide whether or
-        * not we have to employ bounce buffering to guarantee stable pages.
-        */
-       bio_for_each_segment(from, bio, i) {
-               page = from->bv_page;
-               mapping = page_mapping(page);
-               if (!mapping)
-                       continue;
-               bdi = mapping->backing_dev_info;
-               return mapping->host->i_sb->s_flags & MS_SNAP_STABLE;
-       }
-
-       return 0;
+       return test_bit(BIO_SNAP_STABLE, &bio->bi_flags);
 }
 #else
 static int must_snapshot_stable_pages(struct request_queue *q, struct bio *bio)