[PATCH v1 1/1] [io_uring] require RWF_HIPRI for iopoll reads and writes

From: "Stefan Bühler" <source@stbuehler.de>
To: Jens Axboe <axboe@kernel.dk>,
	linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: [PATCH v1 1/1] [io_uring] require RWF_HIPRI for iopoll reads and writes
Date: Wed,  1 May 2019 13:52:23 +0200	[thread overview]
Message-ID: <20190501115223.13296-1-source@stbuehler.de> (raw)

This makes the mapping RWF_HIPRI <-> IOCB_HIPRI <-> iopoll more
consistent; it also allows supporting iopoll operations without
IORING_SETUP_IOPOLL in the future.

Signed-off-by: Stefan Bühler <source@stbuehler.de>
---
 fs/io_uring.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 17eae94a54fc..6a480f04b0f3 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -881,14 +881,16 @@ static int io_prep_rw(struct io_kiocb *req, const struct sqe_submit *s,
 		kiocb->ki_flags |= IOCB_NOWAIT;
 
 	if (ctx->flags & IORING_SETUP_IOPOLL) {
+		/* require O_DIRECT (or DAX) and RWF_HIPRI */
 		if (!(kiocb->ki_flags & IOCB_DIRECT) ||
+		    !(kiocb->ki_flags & IOCB_HIPRI) ||
 		    !kiocb->ki_filp->f_op->iopoll)
 			return -EOPNOTSUPP;
 
 		req->error = 0;
-		kiocb->ki_flags |= IOCB_HIPRI;
 		kiocb->ki_complete = io_complete_rw_iopoll;
 	} else {
+		/* RWF_HIPRI not allowed */
 		if (kiocb->ki_flags & IOCB_HIPRI)
 			return -EINVAL;
 		kiocb->ki_complete = io_complete_rw;
-- 
2.20.1

