This is just the plumbing between the event source (fs/namespace.c) and the
event consumer (fanotify). In itself it does nothing.
Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
---
fs/mount.h | 4 +++
fs/notify/fsnotify.c | 47 +++++++++++++++++++++++++++-----
fs/notify/fsnotify.h | 11 ++++++++
fs/notify/mark.c | 14 ++++++++--
include/linux/fsnotify.h | 20 ++++++++++++++
include/linux/fsnotify_backend.h | 42 ++++++++++++++++++++++++++++
6 files changed, 128 insertions(+), 10 deletions(-)
diff --git a/fs/mount.h b/fs/mount.h
index ffb613cdfeee..82aa3bad7cf5 100644
--- a/fs/mount.h
+++ b/fs/mount.h
@@ -21,6 +21,10 @@ struct mnt_namespace {
struct rcu_head mnt_ns_rcu;
};
u64 event;
+#ifdef CONFIG_FSNOTIFY
+ __u32 n_fsnotify_mask;
+ struct fsnotify_mark_connector __rcu *n_fsnotify_marks;
+#endif
unsigned int nr_mounts; /* # of mounts in the namespace */
unsigned int pending_mounts;
struct rb_node mnt_ns_tree_node; /* node in the mnt_ns_tree */
diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index 8ee495a58d0a..c64b95cf50c7 100644
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -28,6 +28,11 @@ void __fsnotify_vfsmount_delete(struct vfsmount *mnt)
fsnotify_clear_marks_by_mount(mnt);
}
+void __fsnotify_mntns_delete(struct mnt_namespace *mntns)
+{
+ fsnotify_clear_marks_by_mntns(mntns);
+}
+
/**
* fsnotify_unmount_inodes - an sb is unmounting. handle any watched inodes.
* @sb: superblock being unmounted.
@@ -420,7 +425,7 @@ static int send_to_group(__u32 mask, const void *data, int data_type,
file_name, cookie, iter_info);
}
-static struct fsnotify_mark *fsnotify_first_mark(struct fsnotify_mark_connector **connp)
+static struct fsnotify_mark *fsnotify_first_mark(struct fsnotify_mark_connector *const *connp)
{
struct fsnotify_mark_connector *conn;
struct hlist_node *node = NULL;
@@ -538,14 +543,15 @@ int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir,
{
const struct path *path = fsnotify_data_path(data, data_type);
struct super_block *sb = fsnotify_data_sb(data, data_type);
- struct fsnotify_sb_info *sbinfo = fsnotify_sb_info(sb);
+ const struct fsnotify_mnt *mnt_data = fsnotify_data_mnt(data, data_type);
+ struct fsnotify_sb_info *sbinfo = sb ? fsnotify_sb_info(sb) : NULL;
struct fsnotify_iter_info iter_info = {};
struct mount *mnt = NULL;
struct inode *inode2 = NULL;
struct dentry *moved;
int inode2_type;
int ret = 0;
- __u32 test_mask, marks_mask;
+ __u32 test_mask, marks_mask = 0;
if (path)
mnt = real_mount(path->mnt);
@@ -578,17 +584,20 @@ int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir,
if ((!sbinfo || !sbinfo->sb_marks) &&
(!mnt || !mnt->mnt_fsnotify_marks) &&
(!inode || !inode->i_fsnotify_marks) &&
- (!inode2 || !inode2->i_fsnotify_marks))
+ (!inode2 || !inode2->i_fsnotify_marks) &&
+ (!mnt_data || !mnt_data->ns->n_fsnotify_marks))
return 0;
- marks_mask = READ_ONCE(sb->s_fsnotify_mask);
+ if (sb)
+ marks_mask |= READ_ONCE(sb->s_fsnotify_mask);
if (mnt)
marks_mask |= READ_ONCE(mnt->mnt_fsnotify_mask);
if (inode)
marks_mask |= READ_ONCE(inode->i_fsnotify_mask);
if (inode2)
marks_mask |= READ_ONCE(inode2->i_fsnotify_mask);
-
+ if (mnt_data)
+ marks_mask |= READ_ONCE(mnt_data->ns->n_fsnotify_mask);
/*
* If this is a modify event we may need to clear some ignore masks.
@@ -618,6 +627,10 @@ int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir,
iter_info.marks[inode2_type] =
fsnotify_first_mark(&inode2->i_fsnotify_marks);
}
+ if (mnt_data) {
+ iter_info.marks[FSNOTIFY_ITER_TYPE_MNTNS] =
+ fsnotify_first_mark(&mnt_data->ns->n_fsnotify_marks);
+ }
/*
* We need to merge inode/vfsmount/sb mark lists so that e.g. inode mark
@@ -702,11 +715,31 @@ void file_set_fsnotify_mode(struct file *file)
}
#endif
+void fsnotify_mnt(__u32 mask, struct mnt_namespace *ns, struct vfsmount *mnt)
+{
+ struct fsnotify_mnt data = {
+ .ns = ns,
+ .mnt_id = real_mount(mnt)->mnt_id_unique,
+ };
+
+ if (WARN_ON_ONCE(!ns))
+ return;
+
+ /*
+ * This is an optimization as well as making sure fsnotify_init() has
+ * been called.
+ */
+ if (!ns->n_fsnotify_marks)
+ return;
+
+ fsnotify(mask, &data, FSNOTIFY_EVENT_MNT, NULL, NULL, NULL, 0);
+}
+
static __init int fsnotify_init(void)
{
int ret;
- BUILD_BUG_ON(HWEIGHT32(ALL_FSNOTIFY_BITS) != 24);
+ BUILD_BUG_ON(HWEIGHT32(ALL_FSNOTIFY_BITS) != 26);
ret = init_srcu_struct(&fsnotify_mark_srcu);
if (ret)
diff --git a/fs/notify/fsnotify.h b/fs/notify/fsnotify.h
index 663759ed6fbc..5950c7a67f41 100644
--- a/fs/notify/fsnotify.h
+++ b/fs/notify/fsnotify.h
@@ -33,6 +33,12 @@ static inline struct super_block *fsnotify_conn_sb(
return conn->obj;
}
+static inline struct mnt_namespace *fsnotify_conn_mntns(
+ struct fsnotify_mark_connector *conn)
+{
+ return conn->obj;
+}
+
static inline struct super_block *fsnotify_object_sb(void *obj,
enum fsnotify_obj_type obj_type)
{
@@ -89,6 +95,11 @@ static inline void fsnotify_clear_marks_by_sb(struct super_block *sb)
fsnotify_destroy_marks(fsnotify_sb_marks(sb));
}
+static inline void fsnotify_clear_marks_by_mntns(struct mnt_namespace *mntns)
+{
+ fsnotify_destroy_marks(&mntns->n_fsnotify_marks);
+}
+
/*
* update the dentry->d_flags of all of inode's children to indicate if inode cares
* about events that happen to its children.
diff --git a/fs/notify/mark.c b/fs/notify/mark.c
index 4981439e6209..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;
}
@@ -346,12 +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;
}
@@ -724,7 +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;
@@ -770,7 +777,8 @@ static int fsnotify_add_mark_list(struct fsnotify_mark *mark, void *obj,
/* 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
diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h
index 1a9ef8f6784d..589e274adc7d 100644
--- a/include/linux/fsnotify.h
+++ b/include/linux/fsnotify.h
@@ -299,6 +299,11 @@ static inline void fsnotify_vfsmount_delete(struct vfsmount *mnt)
__fsnotify_vfsmount_delete(mnt);
}
+static inline void fsnotify_mntns_delete(struct mnt_namespace *mntns)
+{
+ __fsnotify_mntns_delete(mntns);
+}
+
/*
* fsnotify_inoderemove - an inode is going away
*/
@@ -507,4 +512,19 @@ static inline int fsnotify_sb_error(struct super_block *sb, struct inode *inode,
NULL, NULL, NULL, 0);
}
+static inline void fsnotify_mnt_attach(struct mnt_namespace *ns, struct vfsmount *mnt)
+{
+ fsnotify_mnt(FS_MNT_ATTACH, ns, mnt);
+}
+
+static inline void fsnotify_mnt_detach(struct mnt_namespace *ns, struct vfsmount *mnt)
+{
+ fsnotify_mnt(FS_MNT_DETACH, ns, mnt);
+}
+
+static inline void fsnotify_mnt_move(struct mnt_namespace *ns, struct vfsmount *mnt)
+{
+ fsnotify_mnt(FS_MNT_MOVE, ns, mnt);
+}
+
#endif /* _LINUX_FS_NOTIFY_H */
diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index 0d24a21a8e60..6cd8d1d28b8b 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -59,6 +59,10 @@
#define FS_PRE_ACCESS 0x00100000 /* Pre-content access hook */
+#define FS_MNT_ATTACH 0x01000000 /* Mount was attached */
+#define FS_MNT_DETACH 0x02000000 /* Mount was detached */
+#define FS_MNT_MOVE (FS_MNT_ATTACH | FS_MNT_DETACH)
+
/*
* Set on inode mark that cares about things that happen to its children.
* Always set for dnotify and inotify.
@@ -80,6 +84,9 @@
*/
#define ALL_FSNOTIFY_DIRENT_EVENTS (FS_CREATE | FS_DELETE | FS_MOVE | FS_RENAME)
+/* Mount namespace events */
+#define FSNOTIFY_MNT_EVENTS (FS_MNT_ATTACH | FS_MNT_DETACH)
+
/* Content events can be used to inspect file content */
#define FSNOTIFY_CONTENT_PERM_EVENTS (FS_OPEN_PERM | FS_OPEN_EXEC_PERM | \
FS_ACCESS_PERM)
@@ -108,6 +115,7 @@
/* Events that can be reported to backends */
#define ALL_FSNOTIFY_EVENTS (ALL_FSNOTIFY_DIRENT_EVENTS | \
+ FSNOTIFY_MNT_EVENTS | \
FS_EVENTS_POSS_ON_CHILD | \
FS_DELETE_SELF | FS_MOVE_SELF | \
FS_UNMOUNT | FS_Q_OVERFLOW | FS_IN_IGNORED | \
@@ -298,6 +306,7 @@ enum fsnotify_data_type {
FSNOTIFY_EVENT_PATH,
FSNOTIFY_EVENT_INODE,
FSNOTIFY_EVENT_DENTRY,
+ FSNOTIFY_EVENT_MNT,
FSNOTIFY_EVENT_ERROR,
};
@@ -318,6 +327,11 @@ static inline const struct path *file_range_path(const struct file_range *range)
return range->path;
}
+struct fsnotify_mnt {
+ const struct mnt_namespace *ns;
+ u64 mnt_id;
+};
+
static inline struct inode *fsnotify_data_inode(const void *data, int data_type)
{
switch (data_type) {
@@ -383,6 +397,24 @@ static inline struct super_block *fsnotify_data_sb(const void *data,
}
}
+static inline const struct fsnotify_mnt *fsnotify_data_mnt(const void *data,
+ int data_type)
+{
+ switch (data_type) {
+ case FSNOTIFY_EVENT_MNT:
+ return data;
+ default:
+ return NULL;
+ }
+}
+
+static inline u64 fsnotify_data_mnt_id(const void *data, int data_type)
+{
+ const struct fsnotify_mnt *mnt_data = fsnotify_data_mnt(data, data_type);
+
+ return mnt_data ? mnt_data->mnt_id : 0;
+}
+
static inline struct fs_error_report *fsnotify_data_error_report(
const void *data,
int data_type)
@@ -420,6 +452,7 @@ enum fsnotify_iter_type {
FSNOTIFY_ITER_TYPE_SB,
FSNOTIFY_ITER_TYPE_PARENT,
FSNOTIFY_ITER_TYPE_INODE2,
+ FSNOTIFY_ITER_TYPE_MNTNS,
FSNOTIFY_ITER_TYPE_COUNT
};
@@ -429,6 +462,7 @@ enum fsnotify_obj_type {
FSNOTIFY_OBJ_TYPE_INODE,
FSNOTIFY_OBJ_TYPE_VFSMOUNT,
FSNOTIFY_OBJ_TYPE_SB,
+ FSNOTIFY_OBJ_TYPE_MNTNS,
FSNOTIFY_OBJ_TYPE_COUNT,
FSNOTIFY_OBJ_TYPE_DETACHED = FSNOTIFY_OBJ_TYPE_COUNT
};
@@ -613,8 +647,10 @@ extern int __fsnotify_parent(struct dentry *dentry, __u32 mask, const void *data
extern void __fsnotify_inode_delete(struct inode *inode);
extern void __fsnotify_vfsmount_delete(struct vfsmount *mnt);
extern void fsnotify_sb_delete(struct super_block *sb);
+extern void __fsnotify_mntns_delete(struct mnt_namespace *mntns);
extern void fsnotify_sb_free(struct super_block *sb);
extern u32 fsnotify_get_cookie(void);
+extern void fsnotify_mnt(__u32 mask, struct mnt_namespace *ns, struct vfsmount *mnt);
static inline __u32 fsnotify_parent_needed_mask(__u32 mask)
{
@@ -928,6 +964,9 @@ static inline void __fsnotify_vfsmount_delete(struct vfsmount *mnt)
static inline void fsnotify_sb_delete(struct super_block *sb)
{}
+static inline void __fsnotify_mntns_delete(struct mnt_namespace *mntns)
+{}
+
static inline void fsnotify_sb_free(struct super_block *sb)
{}
@@ -942,6 +981,9 @@ static inline u32 fsnotify_get_cookie(void)
static inline void fsnotify_unmount_inodes(struct super_block *sb)
{}
+static inline void fsnotify_mnt(__u32 mask, struct mnt_namespace *ns, struct vfsmount *mnt)
+{}
+
#endif /* CONFIG_FSNOTIFY */
#endif /* __KERNEL __ */
--
2.48.1
