Commit 700307a2 authored by Eric Paris's avatar Eric Paris
Browse files

fsnotify: use an explicit flag to indicate fsnotify_destroy_mark has been called 



Currently fsnotify check is mark->group is NULL to decide if
fsnotify_destroy_mark() has already been called or not.  With the upcoming
rcu work it is a heck of a lot easier to use an explicit flag than worry
about group being set to NULL.

Signed-off-by: default avatarEric Paris <eparis@redhat.com>
parent a4c6e996

fs/notify/inode_mark.c

+1 −1
Original line number Diff line number Diff line
@@ -187,7 +187,7 @@ int fsnotify_add_inode_mark(struct fsnotify_mark *mark, 
	struct hlist_node *node, *last = NULL;

	int ret = 0;



	mark->flags = FSNOTIFY_MARK_FLAG_INODE;

	mark->flags |= FSNOTIFY_MARK_FLAG_INODE;



	assert_spin_locked(&mark->lock);

	assert_spin_locked(&group->mark_lock);

fs/notify/mark.c

+7 −4
Original line number Diff line number Diff line
@@ -121,12 +121,14 @@ void fsnotify_destroy_mark(struct fsnotify_mark *mark) 


	group = mark->group;



	/* if !group something else already marked this to die */

	if (!group) {

	/* something else already called this function on this mark */

	if (!(mark->flags & FSNOTIFY_MARK_FLAG_ALIVE)) {

		spin_unlock(&mark->lock);

		return;

	}



	mark->flags &= ~FSNOTIFY_MARK_FLAG_ALIVE;



	/* 1 from caller and 1 for being on i_list/g_list */

	BUG_ON(atomic_read(&mark->refcnt) < 2);
@@ -141,7 +143,6 @@ void fsnotify_destroy_mark(struct fsnotify_mark *mark) 
		BUG();



	list_del_init(&mark->g_list);

	mark->group = NULL;



	fsnotify_put_mark(mark); /* for i_list and g_list */
@@ -229,6 +230,8 @@ int fsnotify_add_mark(struct fsnotify_mark *mark, 
	spin_lock(&mark->lock);

	spin_lock(&group->mark_lock);



	mark->flags |= FSNOTIFY_MARK_FLAG_ALIVE;



	mark->group = group;

	list_add(&mark->g_list, &group->marks_list);

	atomic_inc(&group->num_marks);
@@ -258,7 +261,7 @@ int fsnotify_add_mark(struct fsnotify_mark *mark, 


	return ret;

err:

	mark->group = NULL;

	mark->flags &= ~FSNOTIFY_MARK_FLAG_ALIVE;

	list_del_init(&mark->g_list);

	atomic_dec(&group->num_marks);

	fsnotify_put_mark(mark);

fs/notify/vfsmount_mark.c

+1 −1
Original line number Diff line number Diff line
@@ -145,7 +145,7 @@ int fsnotify_add_vfsmount_mark(struct fsnotify_mark *mark, 
	struct hlist_node *node, *last = NULL;

	int ret = 0;



	mark->flags = FSNOTIFY_MARK_FLAG_VFSMOUNT;

	mark->flags |= FSNOTIFY_MARK_FLAG_VFSMOUNT;



	assert_spin_locked(&mark->lock);

	assert_spin_locked(&group->mark_lock);

include/linux/fsnotify_backend.h

+1 −0
Original line number Diff line number Diff line
@@ -300,6 +300,7 @@ struct fsnotify_mark { 
#define FSNOTIFY_MARK_FLAG_VFSMOUNT		0x02

#define FSNOTIFY_MARK_FLAG_OBJECT_PINNED	0x04

#define FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY	0x08

#define FSNOTIFY_MARK_FLAG_ALIVE		0x10

	unsigned int flags;		/* vfsmount or inode mark? */

	void (*free_mark)(struct fsnotify_mark *mark); /* called on final put+free */

};

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