Re: [RFC][PATCH 1/2] fanotify: add support for FAN_UNMOUNT event

On Wed, Apr 19, 2023 at 4:14 PM Jan Kara [off-list ref] wrote:

On Fri 14-04-23 21:29:02, Amir Goldstein wrote:

quoted

inotify generates unsolicited IN_UNMOUNT events for every inode
mark before the filesystem containing the inode is shutdown.

Unlike IN_UNMOUNT, FAN_UNMOUNT is an opt-in event that can only be
set on a mount mark and is generated when the mount is unmounted.

FAN_UNMOUNT requires FAN_REPORT_FID and reports an fid info record
with fsid of the filesystem and an empty file handle.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>

Seeing the discussion further in this thread regarding FAN_IGNORED won't
it be more consistent (extensible) to implement the above functionality as
FAN_IGNORED delivered to mount mark when it is getting destroyed?

I.e., define FAN_IGNORED as an event that gets delivered when a mark is
getting destroyed (with the records identifying the mark). For now start
supporting it on mount marks, later we can add support to other mark types
if there's demand. Thoughts?

Sounds like a good idea.

I will look into it.

Thanks,
Amir.