diff options
Diffstat (limited to 'fs/notify')
| -rw-r--r-- | fs/notify/fsnotify.c | 32 | ||||
| -rw-r--r-- | fs/notify/fsnotify.h | 16 | ||||
| -rw-r--r-- | fs/notify/inode_mark.c | 8 | ||||
| -rw-r--r-- | fs/notify/mark.c | 80 | ||||
| -rw-r--r-- | fs/notify/vfsmount_mark.c | 8 |
5 files changed, 107 insertions, 37 deletions
diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c index b41515d3f081..eae621a18ac9 100644 --- a/fs/notify/fsnotify.c +++ b/fs/notify/fsnotify.c @@ -193,6 +193,7 @@ int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is, struct hlist_node *inode_node = NULL, *vfsmount_node = NULL; struct fsnotify_mark *inode_mark = NULL, *vfsmount_mark = NULL; struct fsnotify_group *inode_group, *vfsmount_group; + struct fsnotify_mark_connector *inode_conn, *vfsmount_conn; struct mount *mnt; int idx, ret = 0; /* global tests shouldn't care about events on child only the specific event */ @@ -210,8 +211,8 @@ int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is, * SRCU because we have no references to any objects and do not * need SRCU to keep them "alive". */ - if (hlist_empty(&to_tell->i_fsnotify_marks) && - (!mnt || hlist_empty(&mnt->mnt_fsnotify_marks))) + if (!to_tell->i_fsnotify_marks && + (!mnt || !mnt->mnt_fsnotify_marks)) return 0; /* * if this is a modify event we may need to clear the ignored masks @@ -226,16 +227,24 @@ int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is, idx = srcu_read_lock(&fsnotify_mark_srcu); if ((mask & FS_MODIFY) || - (test_mask & to_tell->i_fsnotify_mask)) - inode_node = srcu_dereference(to_tell->i_fsnotify_marks.first, - &fsnotify_mark_srcu); + (test_mask & to_tell->i_fsnotify_mask)) { + inode_conn = lockless_dereference(to_tell->i_fsnotify_marks); + if (inode_conn) + inode_node = srcu_dereference(inode_conn->list.first, + &fsnotify_mark_srcu); + } if (mnt && ((mask & FS_MODIFY) || (test_mask & mnt->mnt_fsnotify_mask))) { - vfsmount_node = srcu_dereference(mnt->mnt_fsnotify_marks.first, - &fsnotify_mark_srcu); - inode_node = srcu_dereference(to_tell->i_fsnotify_marks.first, - &fsnotify_mark_srcu); + inode_conn = lockless_dereference(to_tell->i_fsnotify_marks); + if (inode_conn) + inode_node = srcu_dereference(inode_conn->list.first, + &fsnotify_mark_srcu); + vfsmount_conn = lockless_dereference(mnt->mnt_fsnotify_marks); + if (vfsmount_conn) + vfsmount_node = srcu_dereference( + vfsmount_conn->list.first, + &fsnotify_mark_srcu); } /* @@ -293,6 +302,8 @@ out: } EXPORT_SYMBOL_GPL(fsnotify); +extern struct kmem_cache *fsnotify_mark_connector_cachep; + static __init int fsnotify_init(void) { int ret; @@ -303,6 +314,9 @@ static __init int fsnotify_init(void) if (ret) panic("initializing fsnotify_mark_srcu"); + fsnotify_mark_connector_cachep = KMEM_CACHE(fsnotify_mark_connector, + SLAB_PANIC); + return 0; } core_initcall(fsnotify_init); diff --git a/fs/notify/fsnotify.h b/fs/notify/fsnotify.h index 0a3bc2cf192c..eb64c59c9ad1 100644 --- a/fs/notify/fsnotify.h +++ b/fs/notify/fsnotify.h @@ -15,7 +15,7 @@ extern void fsnotify_flush_notify(struct fsnotify_group *group); extern struct srcu_struct fsnotify_mark_srcu; /* Calculate mask of events for a list of marks */ -extern u32 fsnotify_recalc_mask(struct hlist_head *head); +extern u32 fsnotify_recalc_mask(struct fsnotify_mark_connector *conn); /* compare two groups for sorting of marks lists */ extern int fsnotify_compare_groups(struct fsnotify_group *a, @@ -24,7 +24,7 @@ extern int fsnotify_compare_groups(struct fsnotify_group *a, extern void fsnotify_set_inode_mark_mask_locked(struct fsnotify_mark *fsn_mark, __u32 mask); /* Add mark to a proper place in mark list */ -extern int fsnotify_add_mark_list(struct hlist_head *head, +extern int fsnotify_add_mark_list(struct fsnotify_mark_connector **connp, struct fsnotify_mark *mark, int allow_dups); /* add a mark to an inode */ @@ -41,19 +41,21 @@ 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); /* 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); +extern struct fsnotify_mark *fsnotify_find_mark( + struct fsnotify_mark_connector *conn, + struct fsnotify_group *group); /* Destroy all marks in the given list protected by 'lock' */ -extern void fsnotify_destroy_marks(struct hlist_head *head, spinlock_t *lock); +extern void fsnotify_destroy_marks(struct fsnotify_mark_connector *conn, + 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); + 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, + fsnotify_destroy_marks(real_mount(mnt)->mnt_fsnotify_marks, &mnt->mnt_root->d_lock); } /* prepare for freeing all marks associated with given group */ diff --git a/fs/notify/inode_mark.c b/fs/notify/inode_mark.c index a3645249f7ec..e8c6b822ff8d 100644 --- a/fs/notify/inode_mark.c +++ b/fs/notify/inode_mark.c @@ -37,7 +37,7 @@ void fsnotify_recalc_inode_mask(struct inode *inode) { spin_lock(&inode->i_lock); - inode->i_fsnotify_mask = fsnotify_recalc_mask(&inode->i_fsnotify_marks); + inode->i_fsnotify_mask = fsnotify_recalc_mask(inode->i_fsnotify_marks); spin_unlock(&inode->i_lock); __fsnotify_update_child_dentry_flags(inode); @@ -60,7 +60,7 @@ void fsnotify_destroy_inode_mark(struct fsnotify_mark *mark) * hold the inode->i_lock, so this is the perfect time to update the * inode->i_fsnotify_mask */ - inode->i_fsnotify_mask = fsnotify_recalc_mask(&inode->i_fsnotify_marks); + inode->i_fsnotify_mask = fsnotify_recalc_mask(inode->i_fsnotify_marks); spin_unlock(&inode->i_lock); } @@ -82,7 +82,7 @@ struct fsnotify_mark *fsnotify_find_inode_mark(struct fsnotify_group *group, struct fsnotify_mark *mark; spin_lock(&inode->i_lock); - mark = fsnotify_find_mark(&inode->i_fsnotify_marks, group); + mark = fsnotify_find_mark(inode->i_fsnotify_marks, group); spin_unlock(&inode->i_lock); return mark; @@ -135,7 +135,7 @@ int fsnotify_add_inode_mark(struct fsnotify_mark *mark, mark->inode = inode; ret = fsnotify_add_mark_list(&inode->i_fsnotify_marks, mark, allow_dups); - inode->i_fsnotify_mask = fsnotify_recalc_mask(&inode->i_fsnotify_marks); + inode->i_fsnotify_mask = fsnotify_recalc_mask(inode->i_fsnotify_marks); spin_unlock(&inode->i_lock); return ret; diff --git a/fs/notify/mark.c b/fs/notify/mark.c index 44836e539169..24b6191bd6c6 100644 --- a/fs/notify/mark.c +++ b/fs/notify/mark.c @@ -83,6 +83,8 @@ #define FSNOTIFY_REAPER_DELAY (1) /* 1 jiffy */ struct srcu_struct fsnotify_mark_srcu; +struct kmem_cache *fsnotify_mark_connector_cachep; + static DEFINE_SPINLOCK(destroy_lock); static LIST_HEAD(destroy_list); @@ -104,12 +106,15 @@ void fsnotify_put_mark(struct fsnotify_mark *mark) } /* Calculate mask of events for a list of marks */ -u32 fsnotify_recalc_mask(struct hlist_head *head) +u32 fsnotify_recalc_mask(struct fsnotify_mark_connector *conn) { u32 new_mask = 0; struct fsnotify_mark *mark; - hlist_for_each_entry(mark, head, obj_list) + if (!conn) + return 0; + + hlist_for_each_entry(mark, &conn->list, obj_list) new_mask |= mark->mask; return new_mask; } @@ -220,10 +225,14 @@ void fsnotify_destroy_mark(struct fsnotify_mark *mark, fsnotify_free_mark(mark); } -void fsnotify_destroy_marks(struct hlist_head *head, spinlock_t *lock) +void fsnotify_destroy_marks(struct fsnotify_mark_connector *conn, + spinlock_t *lock) { struct fsnotify_mark *mark; + if (!conn) + return; + while (1) { /* * We have to be careful since we can race with e.g. @@ -233,11 +242,12 @@ void fsnotify_destroy_marks(struct hlist_head *head, spinlock_t *lock) * calling fsnotify_destroy_mark() more than once is fine. */ spin_lock(lock); - if (hlist_empty(head)) { + if (hlist_empty(&conn->list)) { spin_unlock(lock); break; } - mark = hlist_entry(head->first, struct fsnotify_mark, obj_list); + mark = hlist_entry(conn->list.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 @@ -251,6 +261,14 @@ void fsnotify_destroy_marks(struct hlist_head *head, spinlock_t *lock) } } +void fsnotify_connector_free(struct fsnotify_mark_connector **connp) +{ + if (*connp) { + kmem_cache_free(fsnotify_mark_connector_cachep, *connp); + *connp = NULL; + } +} + void fsnotify_set_mark_mask_locked(struct fsnotify_mark *mark, __u32 mask) { assert_spin_locked(&mark->lock); @@ -304,21 +322,54 @@ int fsnotify_compare_groups(struct fsnotify_group *a, struct fsnotify_group *b) return -1; } -/* Add mark into proper place in given list of marks */ -int fsnotify_add_mark_list(struct hlist_head *head, struct fsnotify_mark *mark, - int allow_dups) +static int fsnotify_attach_connector_to_object( + struct fsnotify_mark_connector **connp) +{ + struct fsnotify_mark_connector *conn; + + conn = kmem_cache_alloc(fsnotify_mark_connector_cachep, GFP_ATOMIC); + if (!conn) + return -ENOMEM; + INIT_HLIST_HEAD(&conn->list); + /* + * Make sure 'conn' initialization is visible. Matches + * lockless_dereference() in fsnotify(). + */ + smp_wmb(); + *connp = conn; + + return 0; +} + +/* + * Add mark into proper place in given list of marks. These marks may be used + * for the fsnotify backend to determine which event types should be delivered + * to which group and for which inodes. These marks are ordered according to + * priority, highest number first, and then by the group's location in memory. + */ +int fsnotify_add_mark_list(struct fsnotify_mark_connector **connp, + struct fsnotify_mark *mark, int allow_dups) { struct fsnotify_mark *lmark, *last = NULL; + struct fsnotify_mark_connector *conn; int cmp; + int err; + + if (!*connp) { + err = fsnotify_attach_connector_to_object(connp); + if (err) + return err; + } + conn = *connp; /* is mark the first mark? */ - if (hlist_empty(head)) { - hlist_add_head_rcu(&mark->obj_list, head); + if (hlist_empty(&conn->list)) { + hlist_add_head_rcu(&mark->obj_list, &conn->list); return 0; } /* should mark be in the middle of the current list? */ - hlist_for_each_entry(lmark, head, obj_list) { + hlist_for_each_entry(lmark, &conn->list, obj_list) { last = lmark; if ((lmark->group == mark->group) && !allow_dups) @@ -419,12 +470,15 @@ int fsnotify_add_mark(struct fsnotify_mark *mark, struct fsnotify_group *group, * Given a list of marks, find the mark associated with given group. If found * take a reference to that mark and return it, else return NULL. */ -struct fsnotify_mark *fsnotify_find_mark(struct hlist_head *head, +struct fsnotify_mark *fsnotify_find_mark(struct fsnotify_mark_connector *conn, struct fsnotify_group *group) { struct fsnotify_mark *mark; - hlist_for_each_entry(mark, head, obj_list) { + if (!conn) + return NULL; + + hlist_for_each_entry(mark, &conn->list, obj_list) { if (mark->group == group) { fsnotify_get_mark(mark); return mark; diff --git a/fs/notify/vfsmount_mark.c b/fs/notify/vfsmount_mark.c index a8fcab68faef..28815d5cba7c 100644 --- a/fs/notify/vfsmount_mark.c +++ b/fs/notify/vfsmount_mark.c @@ -43,7 +43,7 @@ void fsnotify_recalc_vfsmount_mask(struct vfsmount *mnt) struct mount *m = real_mount(mnt); spin_lock(&mnt->mnt_root->d_lock); - m->mnt_fsnotify_mask = fsnotify_recalc_mask(&m->mnt_fsnotify_marks); + m->mnt_fsnotify_mask = fsnotify_recalc_mask(m->mnt_fsnotify_marks); spin_unlock(&mnt->mnt_root->d_lock); } @@ -60,7 +60,7 @@ void fsnotify_destroy_vfsmount_mark(struct fsnotify_mark *mark) hlist_del_init_rcu(&mark->obj_list); mark->mnt = NULL; - m->mnt_fsnotify_mask = fsnotify_recalc_mask(&m->mnt_fsnotify_marks); + m->mnt_fsnotify_mask = fsnotify_recalc_mask(m->mnt_fsnotify_marks); spin_unlock(&mnt->mnt_root->d_lock); } @@ -75,7 +75,7 @@ struct fsnotify_mark *fsnotify_find_vfsmount_mark(struct fsnotify_group *group, struct fsnotify_mark *mark; spin_lock(&mnt->mnt_root->d_lock); - mark = fsnotify_find_mark(&m->mnt_fsnotify_marks, group); + mark = fsnotify_find_mark(m->mnt_fsnotify_marks, group); spin_unlock(&mnt->mnt_root->d_lock); return mark; @@ -101,7 +101,7 @@ int fsnotify_add_vfsmount_mark(struct fsnotify_mark *mark, spin_lock(&mnt->mnt_root->d_lock); mark->mnt = mnt; ret = fsnotify_add_mark_list(&m->mnt_fsnotify_marks, mark, allow_dups); - m->mnt_fsnotify_mask = fsnotify_recalc_mask(&m->mnt_fsnotify_marks); + m->mnt_fsnotify_mask = fsnotify_recalc_mask(m->mnt_fsnotify_marks); spin_unlock(&mnt->mnt_root->d_lock); return ret; |