block: submit_bio_wait() conversions

It was being open coded in a few places.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Joern Engel <joern@logfs.org>
Cc: Prasad Joshi <prasadjoshi.linux@gmail.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Chris Mason <chris.mason@fusionio.com>
Acked-by: NeilBrown <neilb@suse.de>
diff --git a/fs/logfs/dev_bdev.c b/fs/logfs/dev_bdev.c
index 550475c..0f95f0d 100644
--- a/fs/logfs/dev_bdev.c
+++ b/fs/logfs/dev_bdev.c
@@ -14,16 +14,10 @@
 
 #define PAGE_OFS(ofs) ((ofs) & (PAGE_SIZE-1))
 
-static void request_complete(struct bio *bio, int err)
-{
-	complete((struct completion *)bio->bi_private);
-}
-
 static int sync_request(struct page *page, struct block_device *bdev, int rw)
 {
 	struct bio bio;
 	struct bio_vec bio_vec;
-	struct completion complete;
 
 	bio_init(&bio);
 	bio.bi_max_vecs = 1;
@@ -35,13 +29,8 @@
 	bio.bi_size = PAGE_SIZE;
 	bio.bi_bdev = bdev;
 	bio.bi_sector = page->index * (PAGE_SIZE >> 9);
-	init_completion(&complete);
-	bio.bi_private = &complete;
-	bio.bi_end_io = request_complete;
 
-	submit_bio(rw, &bio);
-	wait_for_completion(&complete);
-	return test_bit(BIO_UPTODATE, &bio.bi_flags) ? 0 : -EIO;
+	return submit_bio_wait(rw, &bio);
 }
 
 static int bdev_readpage(void *_sb, struct page *page)