fsnotify: remove mark->free_list

Free list is used when all marks on given inode / mount should be
destroyed when inode / mount is going away.  However we can free all of
the marks without using a special list with some care.

Signed-off-by: Jan Kara <jack@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Jan Kara 2015-09-04 15:43:09 -07:00 committed by Linus Torvalds
parent 1e39fc0183
commit 925d1132a0
6 changed files with 40 additions and 63 deletions

View File

@ -26,7 +26,6 @@
#include <linux/fsnotify_backend.h>
#include "fsnotify.h"
#include "../mount.h"
/*
* Clear all of the marks on an inode when it is being evicted from core

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@ -6,6 +6,8 @@
#include <linux/srcu.h>
#include <linux/types.h>
#include "../mount.h"
/* destroy all events sitting in this groups notification queue */
extern void fsnotify_flush_notify(struct fsnotify_group *group);
@ -38,15 +40,22 @@ extern int fsnotify_add_vfsmount_mark(struct fsnotify_mark *mark,
extern void fsnotify_destroy_vfsmount_mark(struct fsnotify_mark *mark);
/* inode specific destruction of a mark */
extern void fsnotify_destroy_inode_mark(struct fsnotify_mark *mark);
/* Destroy all marks in the given list */
extern void fsnotify_destroy_marks(struct list_head *to_free);
/* Find mark belonging to given group in the list of marks */
extern struct fsnotify_mark *fsnotify_find_mark(struct hlist_head *head,
struct fsnotify_group *group);
/* run the list of all marks associated with inode and flag them to be freed */
extern void fsnotify_clear_marks_by_inode(struct inode *inode);
/* run the list of all marks associated with vfsmount and flag them to be freed */
extern void fsnotify_clear_marks_by_mount(struct vfsmount *mnt);
/* Destroy all marks in the given list protected by 'lock' */
extern void fsnotify_destroy_marks(struct hlist_head *head, spinlock_t *lock);
/* run the list of all marks associated with inode and destroy them */
static inline void fsnotify_clear_marks_by_inode(struct inode *inode)
{
fsnotify_destroy_marks(&inode->i_fsnotify_marks, &inode->i_lock);
}
/* run the list of all marks associated with vfsmount and destroy them */
static inline void fsnotify_clear_marks_by_mount(struct vfsmount *mnt)
{
fsnotify_destroy_marks(&real_mount(mnt)->mnt_fsnotify_marks,
&mnt->mnt_root->d_lock);
}
/*
* update the dentry->d_flags of all of inode's children to indicate if inode cares
* about events that happen to its children.

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@ -64,26 +64,6 @@ void fsnotify_destroy_inode_mark(struct fsnotify_mark *mark)
spin_unlock(&inode->i_lock);
}
/*
* Given an inode, destroy all of the marks associated with that inode.
*/
void fsnotify_clear_marks_by_inode(struct inode *inode)
{
struct fsnotify_mark *mark;
struct hlist_node *n;
LIST_HEAD(free_list);
spin_lock(&inode->i_lock);
hlist_for_each_entry_safe(mark, n, &inode->i_fsnotify_marks, obj_list) {
list_add(&mark->free_list, &free_list);
hlist_del_init_rcu(&mark->obj_list);
fsnotify_get_mark(mark);
}
spin_unlock(&inode->i_lock);
fsnotify_destroy_marks(&free_list);
}
/*
* Given a group clear all of the inode marks associated with that group.
*/

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@ -203,24 +203,34 @@ void fsnotify_destroy_mark(struct fsnotify_mark *mark,
mutex_unlock(&group->mark_mutex);
}
/*
* Destroy all marks in the given list. The marks must be already detached from
* the original inode / vfsmount.
*/
void fsnotify_destroy_marks(struct list_head *to_free)
void fsnotify_destroy_marks(struct hlist_head *head, spinlock_t *lock)
{
struct fsnotify_mark *mark, *lmark;
struct fsnotify_group *group;
struct fsnotify_mark *mark;
list_for_each_entry_safe(mark, lmark, to_free, free_list) {
spin_lock(&mark->lock);
fsnotify_get_group(mark->group);
group = mark->group;
spin_unlock(&mark->lock);
fsnotify_destroy_mark(mark, group);
while (1) {
/*
* We have to be careful since we can race with e.g.
* fsnotify_clear_marks_by_group() and once we drop 'lock',
* mark can get removed from the obj_list and destroyed. But
* we are holding mark reference so mark cannot be freed and
* calling fsnotify_destroy_mark() more than once is fine.
*/
spin_lock(lock);
if (hlist_empty(head)) {
spin_unlock(lock);
break;
}
mark = hlist_entry(head->first, struct fsnotify_mark, obj_list);
/*
* We don't update i_fsnotify_mask / mnt_fsnotify_mask here
* since inode / mount is going away anyway. So just remove
* mark from the list.
*/
hlist_del_init_rcu(&mark->obj_list);
fsnotify_get_mark(mark);
spin_unlock(lock);
fsnotify_destroy_mark(mark, mark->group);
fsnotify_put_mark(mark);
fsnotify_put_group(group);
}
}

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@ -28,25 +28,6 @@
#include <linux/fsnotify_backend.h>
#include "fsnotify.h"
#include "../mount.h"
void fsnotify_clear_marks_by_mount(struct vfsmount *mnt)
{
struct fsnotify_mark *mark;
struct hlist_node *n;
struct mount *m = real_mount(mnt);
LIST_HEAD(free_list);
spin_lock(&mnt->mnt_root->d_lock);
hlist_for_each_entry_safe(mark, n, &m->mnt_fsnotify_marks, obj_list) {
list_add(&mark->free_list, &free_list);
hlist_del_init_rcu(&mark->obj_list);
fsnotify_get_mark(mark);
}
spin_unlock(&mnt->mnt_root->d_lock);
fsnotify_destroy_marks(&free_list);
}
void fsnotify_clear_vfsmount_marks_by_group(struct fsnotify_group *group)
{

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@ -225,8 +225,6 @@ struct fsnotify_mark {
spinlock_t lock;
/* List of marks for inode / vfsmount [obj_lock] */
struct hlist_node obj_list;
/* tmp list used when freeing this mark */
struct list_head free_list;
union { /* Object pointer [mark->lock, group->mark_mutex] */
struct inode *inode; /* inode this mark is associated with */
struct vfsmount *mnt; /* vfsmount this mark is associated with */