block: fix direct io NOWAIT flag not work

commit 8b44b4d81598 ("block: don't allow multiple bios for IOCB_NOWAIT
issue") backport a upstream fix, but miss commit b77c88c ("block:
pass a block_device and opf to bio_alloc_kiocb"), and introduce this bug.
commit b77c88c ("block: pass a block_device and opf to
bio_alloc_kiocb") have other depend patch, so just fix it.

Fixes: 8b44b4d81598 ("block: don't allow multiple bios for IOCB_NOWAIT issue")
Signed-off-by: Fengnan Chang <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
(cherry picked from commit 4f8244e0a2f4c3eaf65d749f90925b1630f812a0)
Signed-off-by: Vijayendra Suman <[email protected]>

Author: Fengnan Chang

block/fops.c

@@ -259,7 +259,6 @@ static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
 				blk_finish_plug(&plug);
 				return -EAGAIN;
 			}
-			bio->bi_opf |= REQ_NOWAIT;
 		}
 
 		if (is_read) {
@@ -270,6 +269,10 @@ static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
 			bio->bi_opf = dio_bio_write_op(iocb);
 			task_io_account_write(bio->bi_iter.bi_size);
 		}
+
+		if (iocb->ki_flags & IOCB_NOWAIT)
+			bio->bi_opf |= REQ_NOWAIT;
+
 		dio->size += bio->bi_iter.bi_size;
 		pos += bio->bi_iter.bi_size;