1 // SPDX-License-Identifier: GPL-2.0-or-later
32  * fsnotify_unmount_inodes - an sb is unmounting.  handle any watched inodes.
36  * concurrent modifiers. We temporarily drop sb->s_inode_list_lock and CAN block.
42 	spin_lock(&sb->s_inode_list_lock);  in fsnotify_unmount_inodes()
43 	list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {  in fsnotify_unmount_inodes()
49 		spin_lock(&inode->i_lock);  in fsnotify_unmount_inodes()
50 		if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) {  in fsnotify_unmount_inodes()
51 			spin_unlock(&inode->i_lock);  in fsnotify_unmount_inodes()
64 		if (!atomic_read(&inode->i_count)) {  in fsnotify_unmount_inodes()
65 			spin_unlock(&inode->i_lock);  in fsnotify_unmount_inodes()
70 		spin_unlock(&inode->i_lock);  in fsnotify_unmount_inodes()
71 		spin_unlock(&sb->s_inode_list_lock);  in fsnotify_unmount_inodes()
84 		spin_lock(&sb->s_inode_list_lock);  in fsnotify_unmount_inodes()
86 	spin_unlock(&sb->s_inode_list_lock);  in fsnotify_unmount_inodes()
91 	wait_var_event(&sb->s_fsnotify_inode_refs,  in fsnotify_unmount_inodes()
92 		       !atomic_long_read(&sb->s_fsnotify_inode_refs));  in fsnotify_unmount_inodes()
104  * on a child we run all of our children and set a dentry flag saying that the
105  * parent cares.  Thus when an event happens on a child it can quickly tell if
106  * if there is a need to find a parent and send the event to the parent.
113 	if (!S_ISDIR(inode->i_mode))  in __fsnotify_update_child_dentry_flags()
119 	spin_lock(&inode->i_lock);  in __fsnotify_update_child_dentry_flags()
122 	hlist_for_each_entry(alias, &inode->i_dentry, d_u.d_alias) {  in __fsnotify_update_child_dentry_flags()
123 		struct dentry *child;  in __fsnotify_update_child_dentry_flags()  local
126 		 * d_flags to indicate parental interest (their parent is the  in __fsnotify_update_child_dentry_flags()
128 		spin_lock(&alias->d_lock);  in __fsnotify_update_child_dentry_flags()
129 		list_for_each_entry(child, &alias->d_subdirs, d_child) {  in __fsnotify_update_child_dentry_flags()
130 			if (!child->d_inode)  in __fsnotify_update_child_dentry_flags()
133 			spin_lock_nested(&child->d_lock, DENTRY_D_LOCK_NESTED);  in __fsnotify_update_child_dentry_flags()
135 				child->d_flags |= DCACHE_FSNOTIFY_PARENT_WATCHED;  in __fsnotify_update_child_dentry_flags()
137 				child->d_flags &= ~DCACHE_FSNOTIFY_PARENT_WATCHED;  in __fsnotify_update_child_dentry_flags()
138 			spin_unlock(&child->d_lock);  in __fsnotify_update_child_dentry_flags()
140 		spin_unlock(&alias->d_lock);  in __fsnotify_update_child_dentry_flags()
142 	spin_unlock(&inode->i_lock);  in __fsnotify_update_child_dentry_flags()
145 /* Are inode/sb/mount interested in parent and name info with this event? */
151 	/* We only send parent/name to inode/sb/mount for events on non-dir */  in fsnotify_event_needs_parent()
155 	/* Did either inode/sb/mount subscribe for events with parent/name? */  in fsnotify_event_needs_parent()
156 	marks_mask |= fsnotify_parent_needed_mask(inode->i_fsnotify_mask);  in fsnotify_event_needs_parent()
157 	marks_mask |= fsnotify_parent_needed_mask(inode->i_sb->s_fsnotify_mask);  in fsnotify_event_needs_parent()
159 		marks_mask |= fsnotify_parent_needed_mask(mnt->mnt_fsnotify_mask);  in fsnotify_event_needs_parent()
161 	/* Did they subscribe for this event with parent/name info? */  in fsnotify_event_needs_parent()
166  * Notify this dentry's parent about a child's events with child name info
167  * if parent is watching or if inode/sb/mount are interested in events with
168  * parent and name info.
170  * Notify only the child without name info if parent is not watching and
171  * inode/sb/mount are not interested in events with parent and name info.
177 	struct mount *mnt = path ? real_mount(path->mnt) : NULL;  in __fsnotify_parent()
179 	struct dentry *parent;  in __fsnotify_parent()  local
180 	bool parent_watched = dentry->d_flags & DCACHE_FSNOTIFY_PARENT_WATCHED;  in __fsnotify_parent()
189 	 * Do inode/sb/mount care about parent and name info on non-dir?  in __fsnotify_parent()
192 	if (!inode->i_fsnotify_marks && !inode->i_sb->s_fsnotify_marks &&  in __fsnotify_parent()
193 	    (!mnt || !mnt->mnt_fsnotify_marks) && !parent_watched)  in __fsnotify_parent()
196 	parent = NULL;  in __fsnotify_parent()
201 	/* Does parent inode care about events on children? */  in __fsnotify_parent()
202 	parent = dget_parent(dentry);  in __fsnotify_parent()
203 	p_inode = parent->d_inode;  in __fsnotify_parent()
209 	 * Include parent/name in notification either if some notification  in __fsnotify_parent()
210 	 * groups require parent info or the parent is interested in this event.  in __fsnotify_parent()
214 		/* When notifying parent, child should be passed as data */  in __fsnotify_parent()
217 		/* Notify both parent and child with child name info */  in __fsnotify_parent()
229 	dput(parent);  in __fsnotify_parent()
243 	const struct fsnotify_ops *ops = group->ops;  in fsnotify_handle_event()
246 	if (WARN_ON_ONCE(!ops->handle_inode_event))  in fsnotify_handle_event()
254 	 * An event can be sent on child mark iterator instead of inode mark  in fsnotify_handle_event()
256 	 * and have marks on both parent and child.  We can simplify this case.  in fsnotify_handle_event()
265 	ret = ops->handle_inode_event(inode_mark, mask, inode, dir, name);  in fsnotify_handle_event()
270 	 * Some events can be sent on both parent dir and child marks  in fsnotify_handle_event()
271 	 * (e.g. FS_ATTRIB).  If both parent dir and child are watching,  in fsnotify_handle_event()
272 	 * report the event once to parent dir with name and once to child  in fsnotify_handle_event()
275 	return ops->handle_inode_event(child_mark, mask, inode, NULL, NULL);  in fsnotify_handle_event()
289 	if (WARN_ON(!iter_info->report_mask))  in send_to_group()
297 			mark = iter_info->marks[type];  in send_to_group()
299 			    !(mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY))  in send_to_group()
300 				mark->ignored_mask = 0;  in send_to_group()
307 		mark = iter_info->marks[type];  in send_to_group()
310 			group = mark->group;  in send_to_group()
311 			marks_mask |= mark->mask;  in send_to_group()
312 			marks_ignored_mask |= mark->ignored_mask;  in send_to_group()
323 	if (group->ops->handle_event) {  in send_to_group()
324 		return group->ops->handle_event(group, mask, data, data_type, dir,  in send_to_group()
339 		node = srcu_dereference(conn->list.first, &fsnotify_mark_srcu);  in fsnotify_first_mark()
349 		node = srcu_dereference(mark->obj_list.next,  in fsnotify_next_mark()
370 		mark = iter_info->marks[type];  in fsnotify_iter_select_report_types()
372 		    fsnotify_compare_groups(max_prio_group, mark->group) > 0)  in fsnotify_iter_select_report_types()
373 			max_prio_group = mark->group;  in fsnotify_iter_select_report_types()
380 	iter_info->report_mask = 0;  in fsnotify_iter_select_report_types()
382 		mark = iter_info->marks[type];  in fsnotify_iter_select_report_types()
384 		    fsnotify_compare_groups(max_prio_group, mark->group) == 0)  in fsnotify_iter_select_report_types()
388 	return iter_info->report_mask;  in fsnotify_iter_select_report_types()
401 			iter_info->marks[type] =  in fsnotify_iter_next()
402 				fsnotify_next_mark(iter_info->marks[type]);  in fsnotify_iter_next()
407  * fsnotify - This is the main call to fsnotify.
417  * @dir:	optional directory associated with event -
421  * @inode:	optional inode associated with event -
422  *		either @dir or @inode must be non-NULL.
423  *		if both are non-NULL event may be reported to both.
433 	struct inode *child = NULL;  in fsnotify()  local
438 		mnt = real_mount(path->mnt);  in fsnotify()
441 		/* Dirent event - report on TYPE_INODE to dir */  in fsnotify()
445 		 * Event on child - report on TYPE_INODE to dir if it is  in fsnotify()
446 		 * watching children and on TYPE_CHILD to child.  in fsnotify()
448 		child = inode;  in fsnotify()
451 	sb = inode->i_sb;  in fsnotify()
460 	if (!sb->s_fsnotify_marks &&  in fsnotify()
461 	    (!mnt || !mnt->mnt_fsnotify_marks) &&  in fsnotify()
462 	    (!inode || !inode->i_fsnotify_marks) &&  in fsnotify()
463 	    (!child || !child->i_fsnotify_marks))  in fsnotify()
466 	marks_mask = sb->s_fsnotify_mask;  in fsnotify()
468 		marks_mask |= mnt->mnt_fsnotify_mask;  in fsnotify()
470 		marks_mask |= inode->i_fsnotify_mask;  in fsnotify()
471 	if (child)  in fsnotify()
472 		marks_mask |= child->i_fsnotify_mask;  in fsnotify()
486 		fsnotify_first_mark(&sb->s_fsnotify_marks);  in fsnotify()
489 			fsnotify_first_mark(&mnt->mnt_fsnotify_marks);  in fsnotify()
493 			fsnotify_first_mark(&inode->i_fsnotify_marks);  in fsnotify()
495 	if (child) {  in fsnotify()
497 			fsnotify_first_mark(&child->i_fsnotify_marks);  in fsnotify()