Re: [PATCH v9 00/31] file system-wide error monitoring

[Gabriel Krisman Bertazi <krisman@collabora.com>]

Amir Goldstein <amir73il@gmail.com> writes:

>> Also, thank you both for the extensive review and ideas during the
>> development of this series.  It was really appreciated!
>>
>
> Thank you for your appreciated effort!
> It was a wild journey through some interesting experiments, but
> you survived it well ;-)
>
> Would you be interested in pursuing FAN_WB_ERROR after a due rest
> and after all the dust on FAN_FS_ERROR has settled?

I think it would make sense for me to continue working on it, yes.  But,
before that, I think I still have some support to add to FAN_FS_ERROR,
like a detailed, fs-specific, info record, and an error location info
record, which has a use-case in Google Cloud environments.  I have to
discuss priorities internally, but we (collabora) do have an interest in
supporting WB_ERROR too.

For the detailed error report, fanotify could have a new info record
that carries a structure sent out by the file system.  fanotify could
handle the lifetime of this object, by keeping a larger mempool, or
delegate its allocation/destruction to the filesystem.

Like I proposed in an earlier version of FAN_FS_ERROR, the format could
be as simple as:

struct fanotify_error_data_info {
   struct fanotify_event_info_header hdr;
   char data[];
}

I think xfs, at least, would be able to make good use of this record with
xfs_scrub, as the xfs maintainers mentioned.

-- 
Gabriel Krisman Bertazi