From 2f6caa538735189fc29aea69d21ae13a042a35b0 Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@kernel.dk>
Date: Fri, 24 Sep 2021 08:43:54 -0600
Subject: [PATCH] io_uring: don't punt files update to io-wq unconditionally
Git-commit: cdb31c29d397a8076d81fd1458d091c647ef94ba
Patch-mainline: v5.15-rc3
References: stable-5.14.9

[ Upstream commit cdb31c29d397a8076d81fd1458d091c647ef94ba ]

There's no reason to punt it unconditionally, we just need to ensure that
the submit lock grabbing is conditional.

Fixes: 05f3fb3c5397 ("io_uring: avoid ring quiesce for fixed file set unregister and update")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 fs/io_uring.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 187eb1907bde..699a08d724c2 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -5919,19 +5919,16 @@ static int io_files_update(struct io_kiocb *req, unsigned int issue_flags)
 	struct io_uring_rsrc_update2 up;
 	int ret;
 
-	if (issue_flags & IO_URING_F_NONBLOCK)
-		return -EAGAIN;
-
 	up.offset = req->rsrc_update.offset;
 	up.data = req->rsrc_update.arg;
 	up.nr = 0;
 	up.tags = 0;
 	up.resv = 0;
 
-	mutex_lock(&ctx->uring_lock);
+	io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
 	ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE,
 					&up, req->rsrc_update.nr_args);
-	mutex_unlock(&ctx->uring_lock);
+	io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
 
 	if (ret < 0)
 		req_set_fail(req);
-- 
2.26.2