Re: [PATCH 13/23] io_uring: implement bpf prog registration

[Song Liu <songliubraving@fb.com>]

> On May 19, 2021, at 7:13 AM, Pavel Begunkov <asml.silence@gmail.com> wrote:
> 
> [de]register BPF programs through io_uring_register() with new
> IORING_ATTACH_BPF and IORING_DETACH_BPF commands.
> 
> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
> ---
> fs/io_uring.c                 | 81 +++++++++++++++++++++++++++++++++++
> include/uapi/linux/io_uring.h |  2 +
> 2 files changed, 83 insertions(+)
> 
> diff --git a/fs/io_uring.c b/fs/io_uring.c
> index 882b16b5e5eb..b13cbcd5c47b 100644
> --- a/fs/io_uring.c
> +++ b/fs/io_uring.c
> @@ -78,6 +78,7 @@
> #include <linux/task_work.h>
> #include <linux/pagemap.h>
> #include <linux/io_uring.h>
> +#include <linux/bpf.h>
> 
> #define CREATE_TRACE_POINTS
> #include <trace/events/io_uring.h>
> @@ -103,6 +104,8 @@
> #define IORING_MAX_RESTRICTIONS	(IORING_RESTRICTION_LAST + \
> 				 IORING_REGISTER_LAST + IORING_OP_LAST)
> 
> +#define IORING_MAX_BPF_PROGS	100

Is 100 a realistic number here? 

> +
> #define SQE_VALID_FLAGS	(IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK|	\
> 				IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
> 				IOSQE_BUFFER_SELECT)
> @@ -266,6 +269,10 @@ struct io_restriction {
> 	bool registered;
> };
> 

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