From 707527956d90ea4f304188555a97144183af1e49 Mon Sep 17 00:00:00 2001 From: Paul Moore Date: Fri, 19 Aug 2022 16:20:33 -0400 Subject: /dev/null: add IORING_OP_URING_CMD support This patch adds support for the io_uring command pass through, aka IORING_OP_URING_CMD, to the /dev/null driver. As with all of the /dev/null functionality, the implementation is just a simple sink where commands go to die, but it should be useful for developers who need a simple IORING_OP_URING_CMD test device that doesn't require any special hardware. Cc: Arnd Bergmann Cc: Greg Kroah-Hartman Acked-by: Jens Axboe Signed-off-by: Paul Moore --- drivers/char/mem.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'drivers/char') diff --git a/drivers/char/mem.c b/drivers/char/mem.c index 84ca98ed1dad..32a932a065a6 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -480,6 +480,11 @@ static ssize_t splice_write_null(struct pipe_inode_info *pipe, struct file *out, return splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_null); } +static int uring_cmd_null(struct io_uring_cmd *ioucmd, unsigned int issue_flags) +{ + return 0; +} + static ssize_t read_iter_zero(struct kiocb *iocb, struct iov_iter *iter) { size_t written = 0; @@ -663,6 +668,7 @@ static const struct file_operations null_fops = { .read_iter = read_iter_null, .write_iter = write_iter_null, .splice_write = splice_write_null, + .uring_cmd = uring_cmd_null, }; static const struct file_operations __maybe_unused port_fops = { -- cgit v1.2.3