From fd9b8547bc5c34186dc42ea05fb4380d21695374 Mon Sep 17 00:00:00 2001 From: Breno Leitao Date: Thu, 4 May 2023 05:18:55 -0700 Subject: io_uring: Pass whole sqe to commands Currently uring CMD operation relies on having large SQEs, but future operations might want to use normal SQE. The io_uring_cmd currently only saves the payload (cmd) part of the SQE, but, for commands that use normal SQE size, it might be necessary to access the initial SQE fields outside of the payload/cmd block. So, saves the whole SQE other than just the pdu. This changes slightly how the io_uring_cmd works, since the cmd structures and callbacks are not opaque to io_uring anymore. I.e, the callbacks can look at the SQE entries, not only, in the cmd structure. The main advantage is that we don't need to create custom structures for simple commands. Creates io_uring_sqe_cmd() that returns the cmd private data as a null pointer and avoids casting in the callee side. Also, make most of ublk_drv's sqe->cmd priv structure into const, and use io_uring_sqe_cmd() to get the private structure, removing the unwanted cast. (There is one case where the cast is still needed since the header->{len,addr} is updated in the private structure) Suggested-by: Pavel Begunkov Signed-off-by: Breno Leitao Reviewed-by: Keith Busch Reviewed-by: Christoph Hellwig Reviewed-by: Pavel Begunkov Link: https://lore.kernel.org/r/20230504121856.904491-3-leitao@debian.org Signed-off-by: Jens Axboe --- include/linux/io_uring.h | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/io_uring.h b/include/linux/io_uring.h index 35b9328ca335..3399d979ee1c 100644 --- a/include/linux/io_uring.h +++ b/include/linux/io_uring.h @@ -24,7 +24,7 @@ enum io_uring_cmd_flags { struct io_uring_cmd { struct file *file; - const void *cmd; + const struct io_uring_sqe *sqe; union { /* callback to defer completions to task context */ void (*task_work_cb)(struct io_uring_cmd *cmd, unsigned); @@ -66,6 +66,11 @@ static inline void io_uring_free(struct task_struct *tsk) if (tsk->io_uring) __io_uring_free(tsk); } + +static inline const void *io_uring_sqe_cmd(const struct io_uring_sqe *sqe) +{ + return sqe->cmd; +} #else static inline int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw, struct iov_iter *iter, void *ioucmd) -- cgit v1.2.3