On Tue, Jan 15, 2019 at 3:56 AM Jens Axboe <axboe@xxxxxxxxx> wrote:
> diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
> index 542757a4c898..e36c264d74e8 100644
> --- a/include/linux/syscalls.h
> +++ b/include/linux/syscalls.h
> @@ -314,6 +314,8 @@ asmlinkage long sys_io_uring_setup(u32 entries,
> struct io_uring_params __user *p);
> asmlinkage long sys_io_uring_enter(unsigned int fd, u32 to_submit,
> u32 min_complete, u32 flags);
> +asmlinkage long sys_io_uring_register(unsigned int fd, unsigned op,
> + void __user *arg);
>
Would it be possible to make this a typed pointer instead? If this needs to
be extended later to pass a different structure, a new system call may
be better for consistency than overloading the argument in various
ways.
> + * io_uring_register(2) opcodes and arguments
> + */
> +#define IORING_REGISTER_BUFFERS 0
> +#define IORING_UNREGISTER_BUFFERS 1
> +
> +struct io_uring_register_buffers {
> + union {
> + struct iovec *iovecs;
> + __u64 pad;
> + };
> + __u32 nr_iovecs;
> +};
As before, I'd suggest making this structure compatible between 32-bit
and 64-bit architectectures, by avoiding pointer and implied padding
fields.
Arnd
