On Tue, Sep 6, 2022 at 12:48 PM Jan Kara <jack@xxxxxxx> wrote: > > On Sun 04-09-22 18:51:13, Amir Goldstein wrote: > > A new flavor of FAN_MARK_IGNORED_MASK that helps to resolve the > > ambiguity around the combination of event flags and ignore mask. > > > > It is also more strict in the events and flags allowed to be > > set in a non-directory inode mark mask and it mandates the use > > of FAN_MARK_IGNORED_SURV_MODIFY flag on filesystem, mount and > > directory inode marks. > > > > Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> > > <snip> > > > +.BR FAN_MARK_IGNORE " (since Linux 6.0)" > > +.\" commit e252f2ed1c8c6c3884ab5dd34e003ed21f1fe6e0 > > +This flag has a similar effect as setting the > > +.B FAN_MARK_IGNORED_MASK > > +flag. > > +The events in > > +.I mask > > +shall be added to or removed from the ignore mask. > > +Unlike the > > +.B FAN_MARK_IGNORED_MASK > > +flag, > > +this flag also has the effect that the > > +.B FAN_ONDIR , > > +and > > +.B FAN_EVENT_ON_CHILD > > +flags take effect on the ignore mask. > > +Specifically, unless > > +.B FAN_ONDIR > > +flag is set with > > +.BR FAN_MARK_IGNORE , > > +events on directories will not be ignored > > +and if the flag > > +.B FAN_EVENT_ON_CHILD > > +is set, > > +events on children will be ignored. > > +For example, > > +a mark on a directory with combination of > > +a mask with > > +.B FAN_CREATE > > +event > > +and > > +.B FAN_ONDIR > > +flag > > +and an ignore mask with > > +.B FAN_CREATE > > +event > > +and without > > +.B FAN_ONDIR > > +flag, > > +will result in getting only events for creation of sub-directories. > > +When using this flag to add to an ignore mask > > +of a mount, filesystem, or directory inode mark, > > +the > > +.B FAN_MARK_IGNORED_SURV_MODIFY > > +flag must be specified. > > Perhaps a short rationaly why this flag is required would be good here? Here is a bit much IMO. I will add it to the next section. How's that? .B FAN_MARK_IGNORED_SURV_MODIFY The ignore mask shall survive modify events. If this flag is not set, the ignore mask is cleared when a modify event occurs -for the ignored file or directory. +on the marked object. +Omitting this flag is typically used to suppress events +(e.g., +.BR FAN_OPEN ) +for a specific file, +until that specific file's content has been modified. +It is far less useful to suppress events +on an entire filesystem, +or mount, +or on all files inside a directory, +until some file's content has been modified. +For this reason, +the +.B FAN_MARK_IGNORE +flag requires the +.B FAN_MARK_IGNORED_SURV_MODIFY +flag on a mount, +filesystem, +or directory inode mark. +This flag cannot be removed from a mark once set. +When the ignore mask is updated without this flag, +on a mark that was previously updated with the +.B FAN_MARK_IGNORE +and +.B FAN_MARK_IGNORED_SURV_MODIFY +flags, +the update fails with +.B EEXIST +error. +.TP +.B FAN_MARK_IGNORE_SURV +This is a synonym for +.RB ( FAN_MARK_IGNORE | FAN_MARK_IGNORED_SURV_MODIFY ). .TP > > > +Failure to do so will results with > > +.B EINVAL > > +or > > +.B EISDIR > > +error. > > <snip> > > > +.TP > > +.B EISDIR > > +.I flags > > +contains > > +.BR FAN_MARK_IGNORE , > > +and > > +.BR FAN_MARK_IGNORED_SURV_MODIFY , > > I think it should rather be "but does not contain > FAN_MARK_IGNORED_SURV_MODIFY", shouldn't it? > Yes. Good catch! Thanks, Amir.
