io_uring: ensure that io_init_req() passes in the right issue_flags

We can't use 0 here, as io_init_req() is always invoked with the
ctx uring_lock held. Newer kernels have IO_URING_F_UNLOCKED for this,
but previously we used IO_URING_F_NONBLOCK to indicate this as well.

Fixes: cf7f9cd500 ("io_uring: add missing lock in io_get_file_fixed")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

io_uring/io_uring.c

@@ -7310,7 +7310,8 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
 
 	if (io_op_defs[req->opcode].needs_file) {
 		req->file = io_file_get(ctx, req, READ_ONCE(sqe->fd),
-					(sqe_flags & IOSQE_FIXED_FILE), 0);
+					(sqe_flags & IOSQE_FIXED_FILE),
+					IO_URING_F_NONBLOCK);
 		if (unlikely(!req->file))
 			ret = -EBADF;
 	}