Re: [PATCH v4 08/16] fanotify: report file range info with pre-content events

Jan Kara
2024-08-29T10:13:31Z

On Wed 14-08-24 17:25:26, Josef Bacik wrote:
> From: Amir Goldstein <amir73il@gmail.com>
>
> With group class FAN_CLASS_PRE_CONTENT, report offset and length info
> along with FAN_PRE_ACCESS and FAN_PRE_MODIFY permission events.
>
> This information is meant to be used by hierarchical storage managers
> that want to fill partial content of files on first access to range.
>
> Signed-off-by: Amir Goldstein <amir73il@gmail.com>

...

> @@ -191,6 +192,12 @@ struct fanotify_event_info_error {
> __u32 error_count;
> };
>
> +struct fanotify_event_info_range {
> + struct fanotify_event_info_header hdr;

There will be 32-bits of padding here and for UAPI, I prefer to keep that
explicit by adding:

__u32 pad;

here. I can fix it on commit...

> + __u64 offset;
> + __u64 count;
> +};
> +
> /*
> * User space may need to record additional information about its decision.
> * The extra information type records what kind of information is included.

Honza
--
Jan Kara <jack@suse.com>
SUSE Labs, CR