drbd: bio_alloc can't fail if it is allow to sleep

Remove handling of NULL returns from sleeping bio_alloc calls given that
those can't fail.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220124091107.642561-10-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

drivers/block/drbd/drbd_receiver.c

@@ -1281,14 +1281,13 @@ static void submit_one_flush(struct drbd_device *device, struct issue_flush_cont
 {
 	struct bio *bio = bio_alloc(GFP_NOIO, 0);
 	struct one_flush_context *octx = kmalloc(sizeof(*octx), GFP_NOIO);
-	if (!bio || !octx) {
-		drbd_warn(device, "Could not allocate a bio, CANNOT ISSUE FLUSH\n");
+
+	if (!octx) {
+		drbd_warn(device, "Could not allocate a octx, CANNOT ISSUE FLUSH\n");
 		/* FIXME: what else can I do now?  disconnecting or detaching
 		 * really does not help to improve the state of the world, either.
 		 */
-		kfree(octx);
-		if (bio)
-			bio_put(bio);
+		bio_put(bio);
 
 		ctx->error = -ENOMEM;
 		put_ldev(device);
@@ -1646,7 +1645,6 @@ int drbd_submit_peer_request(struct drbd_device *device,
 	unsigned data_size = peer_req->i.size;
 	unsigned n_bios = 0;
 	unsigned nr_pages = (data_size + PAGE_SIZE -1) >> PAGE_SHIFT;
-	int err = -ENOMEM;
 
 	/* TRIM/DISCARD: for now, always use the helper function
 	 * blkdev_issue_zeroout(..., discard=true).
@@ -1688,10 +1686,6 @@ int drbd_submit_peer_request(struct drbd_device *device,
 	 */
 next_bio:
 	bio = bio_alloc(GFP_NOIO, nr_pages);
-	if (!bio) {
-		drbd_err(device, "submit_ee: Allocation of a bio failed (nr_pages=%u)\n", nr_pages);
-		goto fail;
-	}
 	/* > peer_req->i.sector, unless this is the first bio */
 	bio->bi_iter.bi_sector = sector;
 	bio_set_dev(bio, device->ldev->backing_bdev);
@@ -1726,14 +1720,6 @@ int drbd_submit_peer_request(struct drbd_device *device,
 		drbd_submit_bio_noacct(device, fault_type, bio);
 	} while (bios);
 	return 0;
-
-fail:
-	while (bios) {
-		bio = bios;
-		bios = bios->bi_next;
-		bio_put(bio);
-	}
-	return err;
 }
 
 static void drbd_remove_epoch_entry_interval(struct drbd_device *device,