# Re: \[PATCH v3 06/15\] fsnotify: Add helper to detect overflow\_event

- From: Jan Kara \<jack@suse.cz\>
- Date: 2021-07-07 20:14:10 
- List: linux-ext4
- Page: https://ratatoskr.run/linux-ext4/2021/07/209351
- Thread: https://ratatoskr.run/linux-fsdevel/2021/06/208949/t.md

```text
On Tue 29-06-21 15:10:26, Gabriel Krisman Bertazi wrote:
> Similarly to fanotify_is_perm_event and friends, provide a helper
> predicate to say whether a mask is of an overflow event.
> 
> Suggested-by: Amir Goldstein <amir73il@gmail.com>
> Reviewed-by: Amir Goldstein <amir73il@gmail.com>
> Signed-off-by: Gabriel Krisman Bertazi <redacted>
> ---
>  fs/notify/fanotify/fanotify.h    | 3 ++-
>  include/linux/fsnotify_backend.h | 5 +++++
>  2 files changed, 7 insertions(+), 1 deletion(-)

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> 
> diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h
> index fd125a949187..2e005b3a75f2 100644
> --- a/fs/notify/fanotify/fanotify.h
> +++ b/fs/notify/fanotify/fanotify.h
> @@ -328,7 +328,8 @@ static inline struct path *fanotify_event_path(struct fanotify_event *event)
>   */
>  static inline bool fanotify_is_hashed_event(u32 mask)
>  {
> -	return !fanotify_is_perm_event(mask) && !(mask & FS_Q_OVERFLOW);
> +	return !(fanotify_is_perm_event(mask) ||
> +		 fsnotify_is_overflow_event(mask));
>  }
>  
>  static inline unsigned int fanotify_event_hash_bucket(
> diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
> index c4473b467c28..f9e2c6cd0f7d 100644
> --- a/include/linux/fsnotify_backend.h
> +++ b/include/linux/fsnotify_backend.h
> @@ -495,6 +495,11 @@ static inline void fsnotify_queue_overflow(struct fsnotify_group *group)
>  	fsnotify_add_event(group, group->overflow_event, NULL, NULL);
>  }
>  
> +static inline bool fsnotify_is_overflow_event(u32 mask)
> +{
> +	return mask & FS_Q_OVERFLOW;
> +}
> +
>  static inline bool fsnotify_notify_queue_is_empty(struct fsnotify_group *group)
>  {
>  	assert_spin_locked(&group->notification_lock);
> -- 
> 2.32.0
> 
-- 
Jan Kara [ref]
SUSE Labs, CR
```