md: simplify sync_page_io

Use an on-stack bio and biovec for the single page synchronous I/O.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/md/md.c b/drivers/md/md.c
index e2b9dbb..6a27f52 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1021,29 +1021,29 @@ int md_super_wait(struct mddev *mddev)
 int sync_page_io(struct md_rdev *rdev, sector_t sector, int size,
                 struct page *page, int op, int op_flags, bool metadata_op)
 {
-       struct bio *bio = md_bio_alloc_sync(rdev->mddev);
-       int ret;
+       struct bio bio;
+       struct bio_vec bvec;
+
+       bio_init(&bio, &bvec, 1);
 
        if (metadata_op && rdev->meta_bdev)
-               bio_set_dev(bio, rdev->meta_bdev);
+               bio_set_dev(&bio, rdev->meta_bdev);
        else
-               bio_set_dev(bio, rdev->bdev);
-       bio_set_op_attrs(bio, op, op_flags);
+               bio_set_dev(&bio, rdev->bdev);
+       bio.bi_opf = op | op_flags;
        if (metadata_op)
-               bio->bi_iter.bi_sector = sector + rdev->sb_start;
+               bio.bi_iter.bi_sector = sector + rdev->sb_start;
        else if (rdev->mddev->reshape_position != MaxSector &&
                 (rdev->mddev->reshape_backwards ==
                  (sector >= rdev->mddev->reshape_position)))
-               bio->bi_iter.bi_sector = sector + rdev->new_data_offset;
+               bio.bi_iter.bi_sector = sector + rdev->new_data_offset;
        else
-               bio->bi_iter.bi_sector = sector + rdev->data_offset;
-       bio_add_page(bio, page, size, 0);
+               bio.bi_iter.bi_sector = sector + rdev->data_offset;
+       bio_add_page(&bio, page, size, 0);
 
-       submit_bio_wait(bio);
+       submit_bio_wait(&bio);
 
-       ret = !bio->bi_status;
-       bio_put(bio);
-       return ret;
+       return !bio.bi_status;
 }
 EXPORT_SYMBOL_GPL(sync_page_io);