[PATCH v2 bpf-next 2/4] bpf: Make bpf inode storage available to tracing program

[Alexei Starovoitov]

On Tue, Nov 12, 2024 at 12:37 AM Song Liu <song at kernel.org> wrote:
>
> inode storage can be useful for non-LSM program. For example, file* tools
> from bcc/libbpf-tools can use inode storage instead of hash map; fanotify
> fastpath [1] can also use inode storage to store useful data.
>
> Make inode storage available for tracing program. Move bpf inode storage
> from a security blob to inode->i_bpf_storage, and adjust related code
> accordingly.

...

> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index 3559446279c1..479097e4dd5b 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -79,6 +79,7 @@ struct fs_context;
>  struct fs_parameter_spec;
>  struct fileattr;
>  struct iomap_ops;
> +struct bpf_local_storage;
>
>  extern void __init inode_init(void);
>  extern void __init inode_init_early(void);
> @@ -648,6 +649,9 @@ struct inode {
>  #ifdef CONFIG_SECURITY
>         void                    *i_security;
>  #endif
> +#ifdef CONFIG_BPF_SYSCALL
> +       struct bpf_local_storage __rcu *i_bpf_storage;
> +#endif
>

This bit needs an ack from vfs folks.