[PATCH -v1 08/11] fsnotify: add correlations between events

Eric Paris
2009-02-09T21:19:04Z

inotify sends userspace a correlation between events when they are related
(aka when dentries are moved). This adds that same support for all
fsnotify events.

Signed-off-by: Eric Paris <eparis@redhat.com>
---

fs/notify/fsnotify.c | 4 ++--
fs/notify/fsnotify.h | 2 +-
fs/notify/notification.c | 14 +++++++++++++-
include/linux/fsnotify.h | 39 +++++++++++++++++++-------------------
include/linux/fsnotify_backend.h | 11 +++++++++--
5 files changed, 45 insertions(+), 25 deletions(-)

diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index 2aa437b..8b816c0 100644
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -34,7 +34,7 @@ void __fsnotify_inode_delete(struct inode *inode, int flag)
}
EXPORT_SYMBOL_GPL(__fsnotify_inode_delete);

-void fsnotify(struct inode *to_tell, __u64 mask, void *data, int data_is, const char *file_name)
+void fsnotify(struct inode *to_tell, __u64 mask, void *data, int data_is, const char *file_name, u32 cookie)
{
struct fsnotify_group *group;
struct fsnotify_event *event = NULL;
@@ -66,7 +66,7 @@ void fsnotify(struct inode *to_tell, __u64 mask, void *data, int data_is, const
if (!group->ops->should_send_event(group, to_tell, mask))
continue;
if (!event) {
- event = fsnotify_create_event(to_tell, mask, data, data_is, file_name);
+ event = fsnotify_create_event(to_tell, mask, data, data_is, file_name, cookie);
/* shit, we OOM'd and now we can't tell, lets hope something else blows up */
if (!event)
break;
diff --git a/fs/notify/fsnotify.h b/fs/notify/fsnotify.h
index 72e163e..b384fa8 100644
--- a/fs/notify/fsnotify.h
+++ b/fs/notify/fsnotify.h
@@ -17,7 +17,7 @@ extern __u64 fsnotify_mask;

extern void fsnotify_flush_notif(struct fsnotify_group *group);

-extern struct fsnotify_event *fsnotify_create_event(struct inode *to_tell, __u64 mask, void *data, int data_is, const char *name);
+extern struct fsnotify_event *fsnotify_create_event(struct inode *to_tell, __u64 mask, void *data, int data_is, const char *name, u32 cookie);

extern void fsnotify_clear_marks_by_group(struct fsnotify_group *group);
extern void fsnotify_clear_marks_by_inode(struct inode *inode, unsigned int flags);
diff --git a/fs/notify/notification.c b/fs/notify/notification.c
index 21a8b03..a636a1f 100644
--- a/fs/notify/notification.c
+++ b/fs/notify/notification.c
@@ -20,6 +20,7 @@
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/list.h>
+#include <linux/module.h>
#include <linux/mount.h>
#include <linux/mutex.h>
#include <linux/namei.h>
@@ -35,6 +36,13 @@
static struct kmem_cache *event_kmem_cache;
static struct kmem_cache *event_holder_kmem_cache;
static struct fsnotify_event q_overflow_event;
+static atomic_t fsnotify_sync_cookie = ATOMIC_INIT(0);
+
+u32 fsnotify_get_cookie(void)
+{
+ return atomic_inc_return(&fsnotify_sync_cookie);
+}
+EXPORT_SYMBOL_GPL(fsnotify_get_cookie);

/* return 1 if something is available, return 0 otherwise */
int fsnotify_check_notif_queue(struct fsnotify_group *group)
@@ -252,9 +260,11 @@ static void initialize_event(struct fsnotify_event *event)

event->file_name = NULL;
event->name_len = 0;
+
+ event->sync_cookie = 0;
}

-struct fsnotify_event *fsnotify_create_event(struct inode *to_tell, __u64 mask, void *data, int data_is, const char *name)
+struct fsnotify_event *fsnotify_create_event(struct inode *to_tell, __u64 mask, void *data, int data_is, const char *name, u32 cookie)
{
struct fsnotify_event *event;

@@ -272,6 +282,8 @@ struct fsnotify_event *fsnotify_create_event(struct inode *to_tell, __u64 mask,
}
event->name_len = strlen(event->file_name);
}
+
+ event->sync_cookie = cookie;
event->to_tell = to_tell;

switch (data_is) {
diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h
index 3081d86..bdbc897 100644
--- a/include/linux/fsnotify.h
+++ b/include/linux/fsnotify.h
@@ -107,7 +107,7 @@ static inline void fsnotify_parent(struct dentry *dentry, __u64 orig_mask)
if (p_inode && (p_inode->i_fsnotify_mask & mask)) {
dget(parent);
spin_unlock(&dentry->d_lock);
- fsnotify(p_inode, mask, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name);
+ fsnotify(p_inode, mask, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0);
dput(parent);
} else {
spin_unlock(&dentry->d_lock);
@@ -139,7 +139,8 @@ static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir,
int isdir, struct inode *target, struct dentry *moved)
{
struct inode *source = moved->d_inode;
- u32 cookie = inotify_get_cookie();
+ u32 in_cookie = inotify_get_cookie();
+ u32 fs_cookie = fsnotify_get_cookie();
__u64 old_dir_mask = 0;
__u64 new_dir_mask = 0;

@@ -156,23 +157,23 @@ static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir,
old_dir_mask |= FS_MOVED_FROM;
new_dir_mask |= FS_MOVED_TO;

- inotify_inode_queue_event(old_dir, IN_MOVED_FROM|isdir,cookie,old_name,
+ inotify_inode_queue_event(old_dir, IN_MOVED_FROM|isdir, in_cookie, old_name,
source);
- inotify_inode_queue_event(new_dir, IN_MOVED_TO|isdir, cookie, new_name,
+ inotify_inode_queue_event(new_dir, IN_MOVED_TO|isdir, in_cookie, new_name,
source);

- fsnotify(old_dir, old_dir_mask, old_dir, FSNOTIFY_EVENT_INODE, old_name);
- fsnotify(new_dir, new_dir_mask, new_dir, FSNOTIFY_EVENT_INODE, new_name);
+ fsnotify(old_dir, old_dir_mask, old_dir, FSNOTIFY_EVENT_INODE, old_name, fs_cookie);
+ fsnotify(new_dir, new_dir_mask, new_dir, FSNOTIFY_EVENT_INODE, new_name, fs_cookie);

if (target) {
inotify_inode_queue_event(target, IN_DELETE_SELF, 0, NULL, NULL);
inotify_inode_is_dead(target);
- fsnotify(target, FS_DELETE, target, FSNOTIFY_EVENT_INODE, NULL);
+ fsnotify(target, FS_DELETE, target, FSNOTIFY_EVENT_INODE, NULL, 0);
}

if (source) {
inotify_inode_queue_event(source, IN_MOVE_SELF, 0, NULL, NULL);
- fsnotify(source, FS_MOVE_SELF, moved->d_inode, FSNOTIFY_EVENT_INODE, NULL);
+ fsnotify(source, FS_MOVE_SELF, moved->d_inode, FSNOTIFY_EVENT_INODE, NULL, 0);
}
audit_inode_child(new_name, moved, new_dir);
}
@@ -205,7 +206,7 @@ static inline void fsnotify_inoderemove(struct inode *inode)
inotify_inode_queue_event(inode, IN_DELETE_SELF, 0, NULL, NULL);
inotify_inode_is_dead(inode);

- fsnotify(inode, FS_DELETE_SELF, inode, FSNOTIFY_EVENT_INODE, NULL);
+ fsnotify(inode, FS_DELETE_SELF, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
__fsnotify_inode_delete(inode, FSNOTIFY_LAST_DENTRY);
}

@@ -216,7 +217,7 @@ static inline void fsnotify_link_count(struct inode *inode)
{
inotify_inode_queue_event(inode, IN_ATTRIB, 0, NULL, NULL);

- fsnotify(inode, FS_ATTRIB, inode, FSNOTIFY_EVENT_INODE, NULL);
+ fsnotify(inode, FS_ATTRIB, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
}

/*
@@ -228,7 +229,7 @@ static inline void fsnotify_create(struct inode *inode, struct dentry *dentry)
dentry->d_inode);
audit_inode_child(dentry->d_name.name, dentry, inode);

- fsnotify(inode, FS_CREATE, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name);
+ fsnotify(inode, FS_CREATE, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0);
}

/*
@@ -243,7 +244,7 @@ static inline void fsnotify_link(struct inode *dir, struct inode *inode, struct
fsnotify_link_count(inode);
audit_inode_child(new_dentry->d_name.name, new_dentry, dir);

- fsnotify(dir, FS_CREATE, inode, FSNOTIFY_EVENT_INODE, new_dentry->d_name.name);
+ fsnotify(dir, FS_CREATE, inode, FSNOTIFY_EVENT_INODE, new_dentry->d_name.name, 0);
}

/*
@@ -255,7 +256,7 @@ static inline void fsnotify_mkdir(struct inode *inode, struct dentry *dentry)
dentry->d_name.name, dentry->d_inode);
audit_inode_child(dentry->d_name.name, dentry, inode);

- fsnotify(inode, FS_CREATE | FS_IN_ISDIR, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name);
+ fsnotify(inode, FS_CREATE | FS_IN_ISDIR, dentry->d_inode, FSNOTIFY_EVENT_INODE, dentry->d_name.name, 0);
}

/*
@@ -273,7 +274,7 @@ static inline void fsnotify_access(struct dentry *dentry)
inotify_inode_queue_event(inode, mask, 0, NULL, NULL);

fsnotify_parent(dentry, mask);
- fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL);
+ fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
}

/*
@@ -291,7 +292,7 @@ static inline void fsnotify_modify(struct dentry *dentry)
inotify_inode_queue_event(inode, mask, 0, NULL, NULL);

fsnotify_parent(dentry, mask);
- fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL);
+ fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
}

/*
@@ -309,7 +310,7 @@ static inline void fsnotify_open(struct dentry *dentry)
inotify_inode_queue_event(inode, mask, 0, NULL, NULL);

fsnotify_parent(dentry, mask);
- fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL);
+ fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
}

/*
@@ -330,7 +331,7 @@ static inline void fsnotify_close(struct file *file)
inotify_inode_queue_event(inode, mask, 0, NULL, NULL);

fsnotify_parent(dentry, mask);
- fsnotify(inode, mask, file, FSNOTIFY_EVENT_FILE, NULL);
+ fsnotify(inode, mask, file, FSNOTIFY_EVENT_FILE, NULL, 0);
}

/*
@@ -348,7 +349,7 @@ static inline void fsnotify_xattr(struct dentry *dentry)
inotify_inode_queue_event(inode, mask, 0, NULL, NULL);

fsnotify_parent(dentry, mask);
- fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL);
+ fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
}

/*
@@ -386,7 +387,7 @@ static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid)
dentry->d_name.name);

fsnotify_parent(dentry, mask);
- fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL);
+ fsnotify(inode, mask, inode, FSNOTIFY_EVENT_INODE, NULL, 0);
}
}

diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index b86b4ef..c86795d 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -168,6 +168,7 @@ struct fsnotify_event {
atomic_t refcnt; /* how many groups still are using/need to send this event */
__u64 mask; /* the type of access */

+ u32 sync_cookie; /* used to corrolate events, namely inotify mv events */
char *file_name;
size_t name_len;

@@ -201,8 +202,9 @@ struct fsnotify_mark_entry {
#ifdef CONFIG_FSNOTIFY

/* called from the vfs to signal fs events */
-extern void fsnotify(struct inode *to_tell, __u64 mask, void *data, int data_is, const char *name);
+extern void fsnotify(struct inode *to_tell, __u64 mask, void *data, int data_is, const char *name, u32 cookie);
extern void __fsnotify_inode_delete(struct inode *inode, int flag);
+extern u32 fsnotify_get_cookie(void);

/* called from fsnotify interfaces, such as fanotify or dnotify */
extern void fsnotify_recalc_global_mask(void);
@@ -229,12 +231,17 @@ extern void fsnotify_get_mark(struct fsnotify_mark_entry *entry);
extern void fsnotify_put_mark(struct fsnotify_mark_entry *entry);
#else

-static inline void fsnotify(struct inode *to_tell, __u64 mask, void *data, int data_is, const char *name);
+static inline void fsnotify(struct inode *to_tell, __u64 mask, void *data, int data_is, const char *name, u32 cookie);
{}

static inline void __fsnotify_inode_delete(struct inode *inode, int flag)
{}

+static inline u32 fsnotify_get_cookie(void)
+{
+ return 0;
+}
+
#endif /* CONFIG_FSNOTIFY */

#endif /* __KERNEL __ */