drbd: remove bio_alloc_drbd

Given that drbd_md_io_bio_set is initialized during module initialization
and the module fails to load if the initialization fails there is no need
to fall back to plain bio_alloc.

Signed-off-by: Christoph Hellwig <hch@lst.de>
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>

drivers/block/drbd/drbd_actlog.c

@@ -138,7 +138,7 @@ static int _drbd_md_sync_page_io(struct drbd_device *device,
 		op_flags |= REQ_FUA | REQ_PREFLUSH;
 	op_flags |= REQ_SYNC;
 
-	bio = bio_alloc_drbd(GFP_NOIO);
+	bio = bio_alloc_bioset(GFP_NOIO, 1, &drbd_md_io_bio_set);
 	bio_set_dev(bio, bdev->md_bdev);
 	bio->bi_iter.bi_sector = sector;
 	err = -EIO;

drivers/block/drbd/drbd_bitmap.c

@@ -976,7 +976,7 @@ static void drbd_bm_endio(struct bio *bio)
 
 static void bm_page_io_async(struct drbd_bm_aio_ctx *ctx, int page_nr) __must_hold(local)
 {
-	struct bio *bio = bio_alloc_drbd(GFP_NOIO);
+	struct bio *bio = bio_alloc_bioset(GFP_NOIO, 1, &drbd_md_io_bio_set);
 	struct drbd_device *device = ctx->device;
 	struct drbd_bitmap *b = device->bitmap;
 	struct page *page;

drivers/block/drbd/drbd_int.h

@@ -1422,8 +1422,6 @@ extern mempool_t drbd_md_io_page_pool;
 /* We also need to make sure we get a bio
  * when we need it for housekeeping purposes */
 extern struct bio_set drbd_md_io_bio_set;
-/* to allocate from that set */
-extern struct bio *bio_alloc_drbd(gfp_t gfp_mask);
 
 /* And a bio_set for cloning */
 extern struct bio_set drbd_io_bio_set;

drivers/block/drbd/drbd_main.c

@@ -138,19 +138,6 @@ static const struct block_device_operations drbd_ops = {
 	.release	= drbd_release,
 };
 
-struct bio *bio_alloc_drbd(gfp_t gfp_mask)
-{
-	struct bio *bio;
-
-	if (!bioset_initialized(&drbd_md_io_bio_set))
-		return bio_alloc(gfp_mask, 1);
-
-	bio = bio_alloc_bioset(gfp_mask, 1, &drbd_md_io_bio_set);
-	if (!bio)
-		return NULL;
-	return bio;
-}
-
 #ifdef __CHECKER__
 /* When checking with sparse, and this is an inline function, sparse will
    give tons of false positives. When this is a real functions sparse works.