diff options
Diffstat (limited to 'fs/notify/mark.c')
| -rw-r--r-- | fs/notify/mark.c | 26 |
1 files changed, 20 insertions, 6 deletions
diff --git a/fs/notify/mark.c b/fs/notify/mark.c index c45b222cf9c1..798340db69d7 100644 --- a/fs/notify/mark.c +++ b/fs/notify/mark.c @@ -107,6 +107,8 @@ static fsnotify_connp_t *fsnotify_object_connp(void *obj, return &real_mount(obj)->mnt_fsnotify_marks; case FSNOTIFY_OBJ_TYPE_SB: return fsnotify_sb_marks(obj); + case FSNOTIFY_OBJ_TYPE_MNTNS: + return &((struct mnt_namespace *)obj)->n_fsnotify_marks; default: return NULL; } @@ -120,6 +122,8 @@ static __u32 *fsnotify_conn_mask_p(struct fsnotify_mark_connector *conn) return &fsnotify_conn_mount(conn)->mnt_fsnotify_mask; else if (conn->type == FSNOTIFY_OBJ_TYPE_SB) return &fsnotify_conn_sb(conn)->s_fsnotify_mask; + else if (conn->type == FSNOTIFY_OBJ_TYPE_MNTNS) + return &fsnotify_conn_mntns(conn)->n_fsnotify_mask; return NULL; } @@ -138,8 +142,11 @@ static void fsnotify_get_sb_watched_objects(struct super_block *sb) static void fsnotify_put_sb_watched_objects(struct super_block *sb) { - if (atomic_long_dec_and_test(fsnotify_sb_watched_objects(sb))) - wake_up_var(fsnotify_sb_watched_objects(sb)); + atomic_long_t *watched_objects = fsnotify_sb_watched_objects(sb); + + /* the superblock can go away after this decrement */ + if (atomic_long_dec_and_test(watched_objects)) + wake_up_var(watched_objects); } static void fsnotify_get_inode_ref(struct inode *inode) @@ -150,8 +157,11 @@ static void fsnotify_get_inode_ref(struct inode *inode) static void fsnotify_put_inode_ref(struct inode *inode) { - fsnotify_put_sb_watched_objects(inode->i_sb); + /* read ->i_sb before the inode can go away */ + struct super_block *sb = inode->i_sb; + iput(inode); + fsnotify_put_sb_watched_objects(sb); } /* @@ -340,12 +350,15 @@ static void *fsnotify_detach_connector_from_object( fsnotify_conn_mount(conn)->mnt_fsnotify_mask = 0; } else if (conn->type == FSNOTIFY_OBJ_TYPE_SB) { fsnotify_conn_sb(conn)->s_fsnotify_mask = 0; + } else if (conn->type == FSNOTIFY_OBJ_TYPE_MNTNS) { + fsnotify_conn_mntns(conn)->n_fsnotify_mask = 0; } rcu_assign_pointer(*connp, NULL); conn->obj = NULL; conn->type = FSNOTIFY_OBJ_TYPE_DETACHED; - fsnotify_update_sb_watchers(sb, conn); + if (sb) + fsnotify_update_sb_watchers(sb, conn); return inode; } @@ -718,7 +731,7 @@ static int fsnotify_add_mark_list(struct fsnotify_mark *mark, void *obj, * Attach the sb info before attaching a connector to any object on sb. * The sb info will remain attached as long as sb lives. */ - if (!fsnotify_sb_info(sb)) { + if (sb && !fsnotify_sb_info(sb)) { err = fsnotify_attach_info_to_sb(sb); if (err) return err; @@ -764,7 +777,8 @@ restart: /* mark should be the last entry. last is the current last entry */ hlist_add_behind_rcu(&mark->obj_list, &last->obj_list); added: - fsnotify_update_sb_watchers(sb, conn); + if (sb) + fsnotify_update_sb_watchers(sb, conn); /* * Since connector is attached to object using cmpxchg() we are * guaranteed that connector initialization is fully visible by anyone |