From 305474010cdd105e08eb0aec4bc39d2fb5736d58 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 15 Apr 2021 17:36:40 +0800 Subject: [PATCH] io_uring: retry raw bdev writes if we hit -EOPNOTSUPP mainline inclusion from mainline-5.6-rc2 commit faac996ccd5da95bc56b91aa80f2643c2d0a1c56 category: feature bugzilla: https://bugzilla.openeuler.org/show_bug.cgi?id=27 CVE: NA --------------------------- For non-blocking issue, we set IOCB_NOWAIT in the kiocb. However, on a raw block device, this yields an -EOPNOTSUPP return, as non-blocking writes aren't supported. Turn this -EOPNOTSUPP into -EAGAIN, so we retry from blocking context with IOCB_NOWAIT cleared. Cc: stable@vger.kernel.org # 5.5 Signed-off-by: Jens Axboe Signed-off-by: yangerkun Reviewed-by: zhangyi (F) Signed-off-by: Cheng Jian --- fs/io_uring.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/io_uring.c b/fs/io_uring.c index 98243d7f5f3d..c06b0c0808ab 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2335,6 +2335,12 @@ static int io_write(struct io_kiocb *req, struct io_kiocb **nxt, ret2 = call_write_iter(req->file, kiocb, &iter); else ret2 = loop_rw_iter(WRITE, req->file, kiocb, &iter); + /* + * Raw bdev writes will -EOPNOTSUPP for IOCB_NOWAIT. Just + * retry them without IOCB_NOWAIT. + */ + if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT)) + ret2 = -EAGAIN; if (!force_nonblock || ret2 != -EAGAIN) { kiocb_done(kiocb, ret2, nxt, req->in_async); } else { -- GitLab