fsnotify: Remove fsnotify_detach_group_marks()

The function is already mostly contained in what
fsnotify_clear_marks_by_group() does. Just update that function to not
select marks when all of them should be destroyed and remove
fsnotify_detach_group_marks().

Reviewed-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Jan Kara 2017-01-04 10:51:58 +01:00
parent 18f2e0d3a4
commit 2e37c6ca8d
4 changed files with 20 additions and 38 deletions

View file

@ -40,8 +40,6 @@ static inline void fsnotify_clear_marks_by_mount(struct vfsmount *mnt)
{
fsnotify_destroy_marks(&real_mount(mnt)->mnt_fsnotify_marks);
}
/* prepare for freeing all marks associated with given group */
extern void fsnotify_detach_group_marks(struct fsnotify_group *group);
/* Wait until all marks queued for destruction are destroyed */
extern void fsnotify_wait_marks_destroyed(void);

View file

@ -67,7 +67,14 @@ void fsnotify_destroy_group(struct fsnotify_group *group)
fsnotify_group_stop_queueing(group);
/* Clear all marks for this group and queue them for destruction */
fsnotify_detach_group_marks(group);
fsnotify_clear_marks_by_group(group, FSNOTIFY_OBJ_ALL_TYPES);
/*
* Some marks can still be pinned when waiting for response from
* userspace. Wait for those now. fsnotify_prepare_user_wait() will
* not succeed now so this wait is race-free.
*/
wait_event(group->notification_waitq, !atomic_read(&group->user_waits));
/*
* Wait until all marks get really destroyed. We could actually destroy

View file

@ -67,7 +67,7 @@
* - The fs the inode is on is unmounted. (fsnotify_inode_delete/fsnotify_unmount_inodes)
* - Something explicitly requests that it be removed. (fsnotify_destroy_mark)
* - The fsnotify_group associated with the mark is going away and all such marks
* need to be cleaned up. (fsnotify_detach_group_marks)
* need to be cleaned up. (fsnotify_clear_marks_by_group)
*
* This has the very interesting property of being able to run concurrently with
* any (or all) other directions.
@ -651,7 +651,13 @@ void fsnotify_clear_marks_by_group(struct fsnotify_group *group,
{
struct fsnotify_mark *lmark, *mark;
LIST_HEAD(to_free);
struct list_head *head = &to_free;
/* Skip selection step if we want to clear all marks. */
if (type == FSNOTIFY_OBJ_ALL_TYPES) {
head = &group->marks_list;
goto clear;
}
/*
* We have to be really careful here. Anytime we drop mark_mutex, e.g.
* fsnotify_clear_marks_by_inode() can come and free marks. Even in our
@ -668,13 +674,14 @@ void fsnotify_clear_marks_by_group(struct fsnotify_group *group,
}
mutex_unlock(&group->mark_mutex);
clear:
while (1) {
mutex_lock_nested(&group->mark_mutex, SINGLE_DEPTH_NESTING);
if (list_empty(&to_free)) {
if (list_empty(head)) {
mutex_unlock(&group->mark_mutex);
break;
}
mark = list_first_entry(&to_free, struct fsnotify_mark, g_list);
mark = list_first_entry(head, struct fsnotify_mark, g_list);
fsnotify_get_mark(mark);
fsnotify_detach_mark(mark);
mutex_unlock(&group->mark_mutex);
@ -683,38 +690,6 @@ void fsnotify_clear_marks_by_group(struct fsnotify_group *group,
}
}
/*
* Given a group, prepare for freeing all the marks associated with that group.
* The marks are attached to the list of marks prepared for destruction, the
* caller is responsible for freeing marks in that list after SRCU period has
* ended.
*/
void fsnotify_detach_group_marks(struct fsnotify_group *group)
{
struct fsnotify_mark *mark;
while (1) {
mutex_lock_nested(&group->mark_mutex, SINGLE_DEPTH_NESTING);
if (list_empty(&group->marks_list)) {
mutex_unlock(&group->mark_mutex);
break;
}
mark = list_first_entry(&group->marks_list,
struct fsnotify_mark, g_list);
fsnotify_get_mark(mark);
fsnotify_detach_mark(mark);
mutex_unlock(&group->mark_mutex);
fsnotify_free_mark(mark);
fsnotify_put_mark(mark);
}
/*
* Some marks can still be pinned when waiting for response from
* userspace. Wait for those now. fsnotify_prepare_user_wait() will
* not succeed now so this wait is race-free.
*/
wait_event(group->notification_waitq, !atomic_read(&group->user_waits));
}
/* Destroy all marks attached to inode / vfsmount */
void fsnotify_destroy_marks(struct fsnotify_mark_connector __rcu **connp)
{

View file

@ -208,6 +208,8 @@ struct fsnotify_mark_connector {
spinlock_t lock;
#define FSNOTIFY_OBJ_TYPE_INODE 0x01
#define FSNOTIFY_OBJ_TYPE_VFSMOUNT 0x02
#define FSNOTIFY_OBJ_ALL_TYPES (FSNOTIFY_OBJ_TYPE_INODE | \
FSNOTIFY_OBJ_TYPE_VFSMOUNT)
unsigned int flags; /* Type of object [lock] */
union { /* Object pointer [lock] */
struct inode *inode;