block: remove bio_get_nr_vecs()

We can always fill up the bio now, no need to estimate the possible
size based on queue parameters.

Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
[hch: rebased and wrote a changelog]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 2 insertions, 7 deletions

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index c22f175ed024..68b12bbc709f 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2795,9 +2795,7 @@ static int submit_extent_page(int rw, struct extent_io_tree *tree,
 {
         int ret = 0;
         struct bio *bio;
-        int nr;
         int contig = 0;
-        int this_compressed = bio_flags & EXTENT_BIO_COMPRESSED;
         int old_compressed = prev_bio_flags & EXTENT_BIO_COMPRESSED;
         size_t page_size = min_t(size_t, size, PAGE_CACHE_SIZE);
 
@@ -2822,12 +2820,9 @@ static int submit_extent_page(int rw, struct extent_io_tree *tree,
                         return 0;
                 }
         }
-        if (this_compressed)
-                nr = BIO_MAX_PAGES;
-        else
-                nr = bio_get_nr_vecs(bdev);
 
-        bio = btrfs_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH);
+        bio = btrfs_bio_alloc(bdev, sector, BIO_MAX_PAGES,
+                        GFP_NOFS | __GFP_HIGH);
         if (!bio)
                 return -ENOMEM;