fsnotify: add super block object type

Add the infrastructure to attach a mark to a super_block struct
and detach all attached marks when super block is destroyed.

This is going to be used by fanotify backend to setup super block
marks.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Amir Goldstein 2018-09-01 10:41:11 +03:00 committed by Jan Kara
parent 9bdda4e9cf
commit 1e6cb72399
7 changed files with 47 additions and 5 deletions

View File

@ -131,6 +131,11 @@ static void fanotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
seq_printf(m, "fanotify mnt_id:%x mflags:%x mask:%x ignored_mask:%x\n",
mnt->mnt_id, mflags, mark->mask, mark->ignored_mask);
} else if (mark->connector->type == FSNOTIFY_OBJ_TYPE_SB) {
struct super_block *sb = fsnotify_conn_sb(mark->connector);
seq_printf(m, "fanotify sdev:%x mflags:%x mask:%x ignored_mask:%x\n",
sb->s_dev, mflags, mark->mask, mark->ignored_mask);
}
}

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@ -48,7 +48,7 @@ void __fsnotify_vfsmount_delete(struct vfsmount *mnt)
* Called during unmount with no locks held, so needs to be safe against
* concurrent modifiers. We temporarily drop sb->s_inode_list_lock and CAN block.
*/
void fsnotify_unmount_inodes(struct super_block *sb)
static void fsnotify_unmount_inodes(struct super_block *sb)
{
struct inode *inode, *iput_inode = NULL;
@ -98,6 +98,12 @@ void fsnotify_unmount_inodes(struct super_block *sb)
iput(iput_inode);
}
void fsnotify_sb_delete(struct super_block *sb)
{
fsnotify_unmount_inodes(sb);
fsnotify_clear_marks_by_sb(sb);
}
/*
* Given an inode, first check if we care what happens to our children. Inotify
* and dnotify both tell their parents about events. If we care about any event

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@ -21,6 +21,12 @@ static inline struct mount *fsnotify_conn_mount(
return container_of(conn->obj, struct mount, mnt_fsnotify_marks);
}
static inline struct super_block *fsnotify_conn_sb(
struct fsnotify_mark_connector *conn)
{
return container_of(conn->obj, struct super_block, s_fsnotify_marks);
}
/* destroy all events sitting in this groups notification queue */
extern void fsnotify_flush_notify(struct fsnotify_group *group);
@ -43,6 +49,11 @@ static inline void fsnotify_clear_marks_by_mount(struct vfsmount *mnt)
{
fsnotify_destroy_marks(&real_mount(mnt)->mnt_fsnotify_marks);
}
/* run the list of all marks associated with sb and destroy them */
static inline void fsnotify_clear_marks_by_sb(struct super_block *sb)
{
fsnotify_destroy_marks(&sb->s_fsnotify_marks);
}
/* Wait until all marks queued for destruction are destroyed */
extern void fsnotify_wait_marks_destroyed(void);

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@ -115,6 +115,8 @@ static __u32 *fsnotify_conn_mask_p(struct fsnotify_mark_connector *conn)
return &fsnotify_conn_inode(conn)->i_fsnotify_mask;
else if (conn->type == FSNOTIFY_OBJ_TYPE_VFSMOUNT)
return &fsnotify_conn_mount(conn)->mnt_fsnotify_mask;
else if (conn->type == FSNOTIFY_OBJ_TYPE_SB)
return &fsnotify_conn_sb(conn)->s_fsnotify_mask;
return NULL;
}
@ -192,6 +194,8 @@ static struct inode *fsnotify_detach_connector_from_object(
inode->i_fsnotify_mask = 0;
} else if (conn->type == FSNOTIFY_OBJ_TYPE_VFSMOUNT) {
fsnotify_conn_mount(conn)->mnt_fsnotify_mask = 0;
} else if (conn->type == FSNOTIFY_OBJ_TYPE_SB) {
fsnotify_conn_sb(conn)->s_fsnotify_mask = 0;
}
rcu_assign_pointer(*(conn->obj), NULL);

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@ -442,7 +442,7 @@ void generic_shutdown_super(struct super_block *sb)
sync_filesystem(sb);
sb->s_flags &= ~SB_ACTIVE;
fsnotify_unmount_inodes(sb);
fsnotify_sb_delete(sb);
cgroup_writeback_umount();
evict_inodes(sb);

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@ -1464,6 +1464,11 @@ struct super_block {
spinlock_t s_inode_wblist_lock;
struct list_head s_inodes_wb; /* writeback inodes */
#ifdef CONFIG_FSNOTIFY
__u32 s_fsnotify_mask;
struct fsnotify_mark_connector __rcu *s_fsnotify_marks;
#endif
} __randomize_layout;
/* Helper functions so that in most cases filesystems will

View File

@ -206,12 +206,14 @@ struct fsnotify_group {
enum fsnotify_obj_type {
FSNOTIFY_OBJ_TYPE_INODE,
FSNOTIFY_OBJ_TYPE_VFSMOUNT,
FSNOTIFY_OBJ_TYPE_SB,
FSNOTIFY_OBJ_TYPE_COUNT,
FSNOTIFY_OBJ_TYPE_DETACHED = FSNOTIFY_OBJ_TYPE_COUNT
};
#define FSNOTIFY_OBJ_TYPE_INODE_FL (1U << FSNOTIFY_OBJ_TYPE_INODE)
#define FSNOTIFY_OBJ_TYPE_VFSMOUNT_FL (1U << FSNOTIFY_OBJ_TYPE_VFSMOUNT)
#define FSNOTIFY_OBJ_TYPE_SB_FL (1U << FSNOTIFY_OBJ_TYPE_SB)
#define FSNOTIFY_OBJ_ALL_TYPES_MASK ((1U << FSNOTIFY_OBJ_TYPE_COUNT) - 1)
static inline bool fsnotify_valid_obj_type(unsigned int type)
@ -255,6 +257,7 @@ static inline struct fsnotify_mark *fsnotify_iter_##name##_mark( \
FSNOTIFY_ITER_FUNCS(inode, INODE)
FSNOTIFY_ITER_FUNCS(vfsmount, VFSMOUNT)
FSNOTIFY_ITER_FUNCS(sb, SB)
#define fsnotify_foreach_obj_type(type) \
for (type = 0; type < FSNOTIFY_OBJ_TYPE_COUNT; type++)
@ -267,8 +270,8 @@ struct fsnotify_mark_connector;
typedef struct fsnotify_mark_connector __rcu *fsnotify_connp_t;
/*
* Inode / vfsmount point to this structure which tracks all marks attached to
* the inode / vfsmount. The reference to inode / vfsmount is held by this
* Inode/vfsmount/sb point to this structure which tracks all marks attached to
* the inode/vfsmount/sb. The reference to inode/vfsmount/sb is held by this
* structure. We destroy this structure when there are no more marks attached
* to it. The structure is protected by fsnotify_mark_srcu.
*/
@ -335,6 +338,7 @@ extern int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int dat
extern int __fsnotify_parent(const struct path *path, struct dentry *dentry, __u32 mask);
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 u32 fsnotify_get_cookie(void);
static inline int fsnotify_inode_watches_children(struct inode *inode)
@ -455,9 +459,13 @@ static inline void fsnotify_clear_inode_marks_by_group(struct fsnotify_group *gr
{
fsnotify_clear_marks_by_group(group, FSNOTIFY_OBJ_TYPE_INODE_FL);
}
/* run all the marks in a group, and clear all of the sn marks */
static inline void fsnotify_clear_sb_marks_by_group(struct fsnotify_group *group)
{
fsnotify_clear_marks_by_group(group, FSNOTIFY_OBJ_TYPE_SB_FL);
}
extern void fsnotify_get_mark(struct fsnotify_mark *mark);
extern void fsnotify_put_mark(struct fsnotify_mark *mark);
extern void fsnotify_unmount_inodes(struct super_block *sb);
extern void fsnotify_finish_user_wait(struct fsnotify_iter_info *iter_info);
extern bool fsnotify_prepare_user_wait(struct fsnotify_iter_info *iter_info);
@ -484,6 +492,9 @@ static inline void __fsnotify_inode_delete(struct inode *inode)
static inline void __fsnotify_vfsmount_delete(struct vfsmount *mnt)
{}
static inline void fsnotify_sb_delete(struct super_block *sb)
{}
static inline void fsnotify_update_flags(struct dentry *dentry)
{}