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Diffstat (limited to 'include/linux/fsnotify_backend.h')
-rw-r--r--include/linux/fsnotify_backend.h89
1 files changed, 83 insertions, 6 deletions
diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index 9560734759fa..d7d96c806bff 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -518,8 +518,8 @@ struct fsnotify_mark {
struct hlist_node obj_list;
/* Head of list of marks for an object [mark ref] */
struct fsnotify_mark_connector *connector;
- /* Events types to ignore [mark->lock, group->mark_mutex] */
- __u32 ignored_mask;
+ /* Events types and flags to ignore [mark->lock, group->mark_mutex] */
+ __u32 ignore_mask;
/* General fsnotify mark flags */
#define FSNOTIFY_MARK_FLAG_ALIVE 0x0001
#define FSNOTIFY_MARK_FLAG_ATTACHED 0x0002
@@ -529,6 +529,7 @@ struct fsnotify_mark {
/* fanotify mark flags */
#define FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY 0x0100
#define FSNOTIFY_MARK_FLAG_NO_IREF 0x0200
+#define FSNOTIFY_MARK_FLAG_HAS_IGNORE_FLAGS 0x0400
unsigned int flags; /* flags [mark->lock] */
};
@@ -655,15 +656,91 @@ extern void fsnotify_remove_queued_event(struct fsnotify_group *group,
/* functions used to manipulate the marks attached to inodes */
-/* Get mask for calculating object interest taking ignored mask into account */
+/*
+ * Canonical "ignore mask" including event flags.
+ *
+ * Note the subtle semantic difference from the legacy ->ignored_mask.
+ * ->ignored_mask traditionally only meant which events should be ignored,
+ * while ->ignore_mask also includes flags regarding the type of objects on
+ * which events should be ignored.
+ */
+static inline __u32 fsnotify_ignore_mask(struct fsnotify_mark *mark)
+{
+ __u32 ignore_mask = mark->ignore_mask;
+
+ /* The event flags in ignore mask take effect */
+ if (mark->flags & FSNOTIFY_MARK_FLAG_HAS_IGNORE_FLAGS)
+ return ignore_mask;
+
+ /*
+ * Legacy behavior:
+ * - Always ignore events on dir
+ * - Ignore events on child if parent is watching children
+ */
+ ignore_mask |= FS_ISDIR;
+ ignore_mask &= ~FS_EVENT_ON_CHILD;
+ ignore_mask |= mark->mask & FS_EVENT_ON_CHILD;
+
+ return ignore_mask;
+}
+
+/* Legacy ignored_mask - only event types to ignore */
+static inline __u32 fsnotify_ignored_events(struct fsnotify_mark *mark)
+{
+ return mark->ignore_mask & ALL_FSNOTIFY_EVENTS;
+}
+
+/*
+ * Check if mask (or ignore mask) should be applied depending if victim is a
+ * directory and whether it is reported to a watching parent.
+ */
+static inline bool fsnotify_mask_applicable(__u32 mask, bool is_dir,
+ int iter_type)
+{
+ /* Should mask be applied to a directory? */
+ if (is_dir && !(mask & FS_ISDIR))
+ return false;
+
+ /* Should mask be applied to a child? */
+ if (iter_type == FSNOTIFY_ITER_TYPE_PARENT &&
+ !(mask & FS_EVENT_ON_CHILD))
+ return false;
+
+ return true;
+}
+
+/*
+ * Effective ignore mask taking into account if event victim is a
+ * directory and whether it is reported to a watching parent.
+ */
+static inline __u32 fsnotify_effective_ignore_mask(struct fsnotify_mark *mark,
+ bool is_dir, int iter_type)
+{
+ __u32 ignore_mask = fsnotify_ignored_events(mark);
+
+ if (!ignore_mask)
+ return 0;
+
+ /* For non-dir and non-child, no need to consult the event flags */
+ if (!is_dir && iter_type != FSNOTIFY_ITER_TYPE_PARENT)
+ return ignore_mask;
+
+ ignore_mask = fsnotify_ignore_mask(mark);
+ if (!fsnotify_mask_applicable(ignore_mask, is_dir, iter_type))
+ return 0;
+
+ return ignore_mask & ALL_FSNOTIFY_EVENTS;
+}
+
+/* Get mask for calculating object interest taking ignore mask into account */
static inline __u32 fsnotify_calc_mask(struct fsnotify_mark *mark)
{
__u32 mask = mark->mask;
- if (!mark->ignored_mask)
+ if (!fsnotify_ignored_events(mark))
return mask;
- /* Interest in FS_MODIFY may be needed for clearing ignored mask */
+ /* Interest in FS_MODIFY may be needed for clearing ignore mask */
if (!(mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY))
mask |= FS_MODIFY;
@@ -671,7 +748,7 @@ static inline __u32 fsnotify_calc_mask(struct fsnotify_mark *mark)
* If mark is interested in ignoring events on children, the object must
* show interest in those events for fsnotify_parent() to notice it.
*/
- return mask | (mark->ignored_mask & ALL_FSNOTIFY_EVENTS);
+ return mask | mark->ignore_mask;
}
/* Get mask of events for a list of marks */