[mirror_ubuntu-bionic-kernel.git] / fs / mount.h

#include <linux/mount.h>
#include <linux/seq_file.h>
#include <linux/poll.h>

struct mnt_namespace {
	atomic_t		count;
	unsigned int		proc_inum;
	struct mount *	root;
	struct list_head	list;
	struct user_namespace	*user_ns;
	u64			seq;	/* Sequence number to prevent loops */
	wait_queue_head_t poll;
	int event;
};

struct mnt_pcp {
	int mnt_count;
	int mnt_writers;
};

struct mountpoint {
	struct hlist_node m_hash;
	struct dentry *m_dentry;
	int m_count;
};

struct mount {
	struct hlist_node mnt_hash;
	struct mount *mnt_parent;
	struct dentry *mnt_mountpoint;
	struct vfsmount mnt;
	struct rcu_head mnt_rcu;
#ifdef CONFIG_SMP
	struct mnt_pcp __percpu *mnt_pcp;
#else
	int mnt_count;
	int mnt_writers;
#endif
	struct list_head mnt_mounts;	/* list of children, anchored here */
	struct list_head mnt_child;	/* and going through their mnt_child */
	struct list_head mnt_instance;	/* mount instance on sb->s_mounts */
	const char *mnt_devname;	/* Name of device e.g. /dev/dsk/hda1 */
	struct list_head mnt_list;
	struct list_head mnt_expire;	/* link in fs-specific expiry list */
	struct list_head mnt_share;	/* circular list of shared mounts */
	struct list_head mnt_slave_list;/* list of slave mounts */
	struct list_head mnt_slave;	/* slave list entry */
	struct mount *mnt_master;	/* slave is on master->mnt_slave_list */
	struct mnt_namespace *mnt_ns;	/* containing namespace */
	struct mountpoint *mnt_mp;	/* where is it mounted */
#ifdef CONFIG_FSNOTIFY
	struct hlist_head mnt_fsnotify_marks;
	__u32 mnt_fsnotify_mask;
#endif
	int mnt_id;			/* mount identifier */
	int mnt_group_id;		/* peer group identifier */
	int mnt_expiry_mark;		/* true if marked for expiry */
	int mnt_pinned;
	struct path mnt_ex_mountpoint;
};

#define MNT_NS_INTERNAL ERR_PTR(-EINVAL) /* distinct from any mnt_namespace */

static inline struct mount *real_mount(struct vfsmount *mnt)
{
	return container_of(mnt, struct mount, mnt);
}

static inline int mnt_has_parent(struct mount *mnt)
{
	return mnt != mnt->mnt_parent;
}

static inline int is_mounted(struct vfsmount *mnt)
{
	/* neither detached nor internal? */
	return !IS_ERR_OR_NULL(real_mount(mnt)->mnt_ns);
}

extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *);
extern struct mount *__lookup_mnt_last(struct vfsmount *, struct dentry *);

extern bool legitimize_mnt(struct vfsmount *, unsigned);

static inline void get_mnt_ns(struct mnt_namespace *ns)
{
	atomic_inc(&ns->count);
}

extern seqlock_t mount_lock;

static inline void lock_mount_hash(void)
{
	write_seqlock(&mount_lock);
}

static inline void unlock_mount_hash(void)
{
	write_sequnlock(&mount_lock);
}

struct proc_mounts {
	struct seq_file m;
	struct mnt_namespace *ns;
	struct path root;
	int (*show)(struct seq_file *, struct vfsmount *);
};

#define proc_mounts(p) (container_of((p), struct proc_mounts, m))

extern const struct seq_operations mounts_op;
Commit	Line	Data
b2dba1af	1	#include <linux/mount.h>
0226f492 AV	2	#include <linux/seq_file.h>
	3	#include <linux/poll.h>
	4
	5	struct mnt_namespace {
	6	atomic_t count;
98f842e6	7	unsigned int proc_inum;
be08d6d2	8	struct mount * root;
0226f492	9	struct list_head list;
771b1371	10	struct user_namespace *user_ns;
8823c079	11	u64 seq; /* Sequence number to prevent loops */
0226f492 AV	12	wait_queue_head_t poll;
	13	int event;
	14	};
b2dba1af	15
68e8a9fe AV	16	struct mnt_pcp {
	17	int mnt_count;
	18	int mnt_writers;
	19	};
	20
84d17192	21	struct mountpoint {
0818bf27	22	struct hlist_node m_hash;
84d17192 AV	23	struct dentry *m_dentry;
	24	int m_count;
	25	};
	26
7d6fec45	27	struct mount {
38129a13	28	struct hlist_node mnt_hash;
0714a533	29	struct mount *mnt_parent;
a73324da	30	struct dentry *mnt_mountpoint;
7d6fec45	31	struct vfsmount mnt;
48a066e7	32	struct rcu_head mnt_rcu;
68e8a9fe AV	33	#ifdef CONFIG_SMP
68e8a9fe AV	34	struct mnt_pcp __percpu *mnt_pcp;
68e8a9fe AV	35	#else
	36	int mnt_count;
	37	int mnt_writers;
	38	#endif
6b41d536 AV	39	struct list_head mnt_mounts; /* list of children, anchored here */
6b41d536 AV	40	struct list_head mnt_child; /* and going through their mnt_child */
39f7c4db	41	struct list_head mnt_instance; /* mount instance on sb->s_mounts */
52ba1621	42	const char mnt_devname; / Name of device e.g. /dev/dsk/hda1 */
1a4eeaf2	43	struct list_head mnt_list;
6776db3d AV	44	struct list_head mnt_expire; /* link in fs-specific expiry list */
	45	struct list_head mnt_share; /* circular list of shared mounts */
	46	struct list_head mnt_slave_list;/* list of slave mounts */
	47	struct list_head mnt_slave; /* slave list entry */
32301920	48	struct mount mnt_master; / slave is on master->mnt_slave_list */
143c8c91	49	struct mnt_namespace mnt_ns; / containing namespace */
84d17192	50	struct mountpoint mnt_mp; / where is it mounted */
c63181e6 AV	51	#ifdef CONFIG_FSNOTIFY
	52	struct hlist_head mnt_fsnotify_marks;
	53	__u32 mnt_fsnotify_mask;
	54	#endif
15169fe7 AV	55	int mnt_id; /* mount identifier */
15169fe7 AV	56	int mnt_group_id; /* peer group identifier */
863d684f AV	57	int mnt_expiry_mark; /* true if marked for expiry */
863d684f AV	58	int mnt_pinned;
aba809cf	59	struct path mnt_ex_mountpoint;
7d6fec45 AV	60	};
7d6fec45 AV	61
f7a99c5b AV	62	#define MNT_NS_INTERNAL ERR_PTR(-EINVAL) /* distinct from any mnt_namespace */
f7a99c5b AV	63
7d6fec45 AV	64	static inline struct mount real_mount(struct vfsmount mnt)
	65	{
	66	return container_of(mnt, struct mount, mnt);
	67	}
	68
676da58d	69	static inline int mnt_has_parent(struct mount *mnt)
b2dba1af	70	{
0714a533	71	return mnt != mnt->mnt_parent;
b2dba1af	72	}
c7105365	73
f7a99c5b AV	74	static inline int is_mounted(struct vfsmount *mnt)
	75	{
	76	/* neither detached nor internal? */
260a459d	77	return !IS_ERR_OR_NULL(real_mount(mnt)->mnt_ns);
f7a99c5b AV	78	}
f7a99c5b AV	79
474279dc AV	80	extern struct mount __lookup_mnt(struct vfsmount , struct dentry *);
474279dc AV	81	extern struct mount __lookup_mnt_last(struct vfsmount , struct dentry *);
0226f492	82
48a066e7 AV	83	extern bool legitimize_mnt(struct vfsmount *, unsigned);
48a066e7 AV	84
0226f492 AV	85	static inline void get_mnt_ns(struct mnt_namespace *ns)
	86	{
	87	atomic_inc(&ns->count);
	88	}
	89
48a066e7	90	extern seqlock_t mount_lock;
719ea2fb AV	91
	92	static inline void lock_mount_hash(void)
	93	{
48a066e7	94	write_seqlock(&mount_lock);
719ea2fb AV	95	}
	96
	97	static inline void unlock_mount_hash(void)
	98	{
48a066e7	99	write_sequnlock(&mount_lock);
719ea2fb AV	100	}
719ea2fb AV	101
0226f492	102	struct proc_mounts {
6ce6e24e	103	struct seq_file m;
0226f492 AV	104	struct mnt_namespace *ns;
	105	struct path root;
	106	int (show)(struct seq_file , struct vfsmount *);
	107	};
	108
6ce6e24e AV	109	#define proc_mounts(p) (container_of((p), struct proc_mounts, m))
6ce6e24e AV	110
0226f492	111	extern const struct seq_operations mounts_op;