1 files changed, 12 insertions, 52 deletions

diff --git a/fs/block_dev.c b/fs/block_dev.c
index a6f7c892cb4a..677cb364d33f 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -345,24 +345,15 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
 	struct bio *bio;
 	bool is_poll = (iocb->ki_flags & IOCB_HIPRI) != 0;
 	bool is_read = (iov_iter_rw(iter) == READ), is_sync;
-	bool nowait = (iocb->ki_flags & IOCB_NOWAIT) != 0;
 	loff_t pos = iocb->ki_pos;
 	blk_qc_t qc = BLK_QC_T_NONE;
-	gfp_t gfp;
-	ssize_t ret;
+	int ret = 0;
 
 	if ((pos | iov_iter_alignment(iter)) &
 	    (bdev_logical_block_size(bdev) - 1))
 		return -EINVAL;
 
-	if (nowait)
-		gfp = GFP_NOWAIT;
-	else
-		gfp = GFP_KERNEL;
-
-	bio = bio_alloc_bioset(gfp, nr_pages, &blkdev_dio_pool);
-	if (!bio)
-		return -EAGAIN;
+	bio = bio_alloc_bioset(GFP_KERNEL, nr_pages, &blkdev_dio_pool);
 
 	dio = container_of(bio, struct blkdev_dio, bio);
 	dio->is_sync = is_sync = is_sync_kiocb(iocb);
@@ -384,10 +375,7 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
 	if (!is_poll)
 		blk_start_plug(&plug);
 
-	ret = 0;
 	for (;;) {
-		int err;
-
 		bio_set_dev(bio, bdev);
 		bio->bi_iter.bi_sector = pos >> 9;
 		bio->bi_write_hint = iocb->ki_hint;
@@ -395,10 +383,8 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
 		bio->bi_end_io = blkdev_bio_end_io;
 		bio->bi_ioprio = iocb->ki_ioprio;
 
-		err = bio_iov_iter_get_pages(bio, iter);
-		if (unlikely(err)) {
-			if (!ret)
-				ret = err;
+		ret = bio_iov_iter_get_pages(bio, iter);
+		if (unlikely(ret)) {
 			bio->bi_status = BLK_STS_IOERR;
 			bio_endio(bio);
 			break;
@@ -413,14 +399,6 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
 			task_io_account_write(bio->bi_iter.bi_size);
 		}
 
-		/*
-		 * Tell underlying layer to not block for resource shortage.
-		 * And if we would have blocked, return error inline instead
-		 * of through the bio->bi_end_io() callback.
-		 */
-		if (nowait)
-			bio->bi_opf |= (REQ_NOWAIT | REQ_NOWAIT_INLINE);
-
 		dio->size += bio->bi_iter.bi_size;
 		pos += bio->bi_iter.bi_size;
 
@@ -434,12 +412,6 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
 			}
 
 			qc = submit_bio(bio);
-			if (qc == BLK_QC_T_EAGAIN) {
-				if (!ret)
-					ret = -EAGAIN;
-				goto error;
-			}
-			ret = dio->size;
 
 			if (polled)
 				WRITE_ONCE(iocb->ki_cookie, qc);
@@ -460,20 +432,8 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
 			atomic_inc(&dio->ref);
 		}
 
-		qc = submit_bio(bio);
-		if (qc == BLK_QC_T_EAGAIN) {
-			if (!ret)
-				ret = -EAGAIN;
-			goto error;
-		}
-		ret = dio->size;
-
-		bio = bio_alloc(gfp, nr_pages);
-		if (!bio) {
-			if (!ret)
-				ret = -EAGAIN;
-			goto error;
-		}
+		submit_bio(bio);
+		bio = bio_alloc(GFP_KERNEL, nr_pages);
 	}
 
 	if (!is_poll)
@@ -493,16 +453,13 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
 	}
 	__set_current_state(TASK_RUNNING);
 
-out:
 	if (!ret)
 		ret = blk_status_to_errno(dio->bio.bi_status);
+	if (likely(!ret))
+		ret = dio->size;
 
 	bio_put(&dio->bio);
 	return ret;
-error:
-	if (!is_poll)
-		blk_finish_plug(&plug);
-	goto out;
 }
 
 static ssize_t
@@ -1754,7 +1711,10 @@ int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder)
 
 		/* finish claiming */
 		mutex_lock(&bdev->bd_mutex);
-		bd_finish_claiming(bdev, whole, holder);
+		if (!res)
+			bd_finish_claiming(bdev, whole, holder);
+		else
+			bd_abort_claiming(bdev, whole, holder);
 		/*
 		 * Block event polling for write claims if requested.  Any
 		 * write holder makes the write_holder state stick until