On Tue, Mar 30, 2021 at 12:31 PM Amir Goldstein <amir73il@xxxxxxxxx> wrote: > > On Tue, Mar 30, 2021 at 10:31 AM Christian Brauner > <christian.brauner@xxxxxxxxxx> wrote: > > > > On Sun, Mar 28, 2021 at 06:56:24PM +0300, Amir Goldstein wrote: > > > Add a high level hook fsnotify_path_create() which is called from > > > syscall context where mount context is available, so that FAN_CREATE > > > event can be added to a mount mark mask. > > > > > > This high level hook is called in addition to fsnotify_create(), > > > fsnotify_mkdir() and fsnotify_link() hooks in vfs helpers where the mount > > > context is not available. > > > > > > In the context where fsnotify_path_create() will be called, a dentry flag > > > flag is set on the new dentry the suppress the FS_CREATE event in the vfs > > > level hooks. > > > > > > This functionality was requested by Christian Brauner to replace > > > recursive inotify watches for detecting when some path was created under > > > an idmapped mount without having to monitor FAN_CREATE events in the > > > entire filesystem. > > > > > > In combination with more changes to allow unprivileged fanotify listener > > > to watch an idmapped mount, this functionality would be usable also by > > > nested container managers. > > > > > > Link: https://lore.kernel.org/linux-fsdevel/20210318143140.jxycfn3fpqntq34z@wittgenstein/ > > > Cc: Christian Brauner <christian.brauner@xxxxxxxxxx> > > > Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> > > > --- > > > > Was about to look at this. Does this require preliminary patches since > > it doesn't apply to current master. If so, can you just give me a link > > to a branch so I can pull from that? :) > > > > The patch is less useful on its own. > Better take the entire work for the demo which includes this patch: > > [1] https://github.com/amir73il/linux/commits/fanotify_userns > [2] https://github.com/amir73il/inotify-tools/commits/fanotify_userns > Christian, Apologies for the fast moving target. I just force force the kernel+demo branches to include support for the two extra events (delete and move) on mount mark. 3dd3d7f02717...6cfe8f7a9148 fanotify_userns -> fanotify_userns (forced update) The same demo I described before with a mix of: - CREATE event on MOUNT mark - Rest of events on recursive inode marks Still work when running demo script with --fanotify --recursive on idmapped mount But now the demo also works with --global on idmapped mount by setting up only a mount mark to watch most events excluding the unsupported events (see below). Thanks, Amir. # ./test_demo.sh /mnt 0 + WD=/mnt + ID=0 ... + inotifywatch --global -w --timeout -2 /mnt Establishing filesystem global watch... ... total modify close_write move_self create delete filename 3 0 1 0 1 1 /mnt/a/1 (deleted) 2 0 1 0 1 0 /mnt/a/0 (deleted) 2 0 1 0 1 0 /mnt/a/2 2 0 1 0 1 0 /mnt/a/3 2 0 0 0 1 1 /mnt/a/dir1 (deleted) 2 0 1 0 1 0 /mnt/a/dir2/A/B/C/file2 1 0 0 0 1 0 /mnt/a/dir0 (deleted) 1 0 0 0 1 0 /mnt/a/dir2 1 0 0 0 1 0 /mnt/a/dir2/A 1 0 0 0 1 0 /mnt/a/dir2/A/B 1 0 0 0 1 0 /mnt/a/dir2/A/B/C
