[mirror_ubuntu-jammy-kernel.git] / fs / autofs4 / autofs_i.h

/* -*- c -*- ------------------------------------------------------------- *
 *   
 * linux/fs/autofs/autofs_i.h
 *
 *   Copyright 1997-1998 Transmeta Corporation - All Rights Reserved
 *   Copyright 2005-2006 Ian Kent <raven@themaw.net>
 *
 * This file is part of the Linux kernel and is made available under
 * the terms of the GNU General Public License, version 2, or at your
 * option, any later version, incorporated herein by reference.
 *
 * ----------------------------------------------------------------------- */

/* Internal header file for autofs */

#include <linux/auto_fs4.h>
#include <linux/auto_dev-ioctl.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/list.h>

/* This is the range of ioctl() numbers we claim as ours */
#define AUTOFS_IOC_FIRST     AUTOFS_IOC_READY
#define AUTOFS_IOC_COUNT     32

#define AUTOFS_DEV_IOCTL_IOC_FIRST	(AUTOFS_DEV_IOCTL_VERSION)
#define AUTOFS_DEV_IOCTL_IOC_COUNT	(AUTOFS_IOC_COUNT - 11)

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/string.h>
#include <linux/wait.h>
#include <linux/sched.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <asm/current.h>
#include <asm/uaccess.h>

/* #define DEBUG */

#define DPRINTK(fmt, ...)				\
	pr_debug("pid %d: %s: " fmt "\n",		\
		current->pid, __func__, ##__VA_ARGS__)

#define AUTOFS_WARN(fmt, ...)				\
	printk(KERN_WARNING "pid %d: %s: " fmt "\n",	\
		current->pid, __func__, ##__VA_ARGS__)

#define AUTOFS_ERROR(fmt, ...)				\
	printk(KERN_ERR "pid %d: %s: " fmt "\n",	\
		current->pid, __func__, ##__VA_ARGS__)

/* Unified info structure.  This is pointed to by both the dentry and
   inode structures.  Each file in the filesystem has an instance of this
   structure.  It holds a reference to the dentry, so dentries are never
   flushed while the file exists.  All name lookups are dealt with at the
   dentry level, although the filesystem can interfere in the validation
   process.  Readdir is implemented by traversing the dentry lists. */
struct autofs_info {
	struct dentry	*dentry;
	struct inode	*inode;

	int		flags;

	struct completion expire_complete;

	struct list_head active;
	int active_count;

	struct list_head expiring;

	struct autofs_sb_info *sbi;
	unsigned long last_used;
	atomic_t count;

	kuid_t uid;
	kgid_t gid;
};

#define AUTOFS_INF_EXPIRING	(1<<0) /* dentry is in the process of expiring */
#define AUTOFS_INF_PENDING	(1<<2) /* dentry pending mount */

struct autofs_wait_queue {
	wait_queue_head_t queue;
	struct autofs_wait_queue *next;
	autofs_wqt_t wait_queue_token;
	/* We use the following to see what we are waiting for */
	struct qstr name;
	u32 dev;
	u64 ino;
	kuid_t uid;
	kgid_t gid;
	pid_t pid;
	pid_t tgid;
	/* This is for status reporting upon return */
	int status;
	unsigned int wait_ctr;
};

#define AUTOFS_SBI_MAGIC 0x6d4a556d

struct autofs_sb_info {
	u32 magic;
	int pipefd;
	struct file *pipe;
	struct pid *oz_pgrp;
	int catatonic;
	int version;
	int sub_version;
	int min_proto;
	int max_proto;
	unsigned long exp_timeout;
	unsigned int type;
	int reghost_enabled;
	int needs_reghost;
	struct super_block *sb;
	struct mutex wq_mutex;
	struct mutex pipe_mutex;
	spinlock_t fs_lock;
	struct autofs_wait_queue *queues; /* Wait queue pointer */
	spinlock_t lookup_lock;
	struct list_head active_list;
	struct list_head expiring_list;
	struct rcu_head rcu;
};

static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb)
{
	return (struct autofs_sb_info *)(sb->s_fs_info);
}

static inline struct autofs_info *autofs4_dentry_ino(struct dentry *dentry)
{
	return (struct autofs_info *)(dentry->d_fsdata);
}

/* autofs4_oz_mode(): do we see the man behind the curtain?  (The
   processes which do manipulations for us in user space sees the raw
   filesystem without "magic".) */

static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) {
	return sbi->catatonic || task_pgrp(current) == sbi->oz_pgrp;
}

struct inode *autofs4_get_inode(struct super_block *, umode_t);
void autofs4_free_ino(struct autofs_info *);

/* Expiration */
int is_autofs4_dentry(struct dentry *);
int autofs4_expire_wait(struct dentry *dentry, int rcu_walk);
int autofs4_expire_run(struct super_block *, struct vfsmount *,
			struct autofs_sb_info *,
			struct autofs_packet_expire __user *);
int autofs4_do_expire_multi(struct super_block *sb, struct vfsmount *mnt,
			    struct autofs_sb_info *sbi, int when);
int autofs4_expire_multi(struct super_block *, struct vfsmount *,
			struct autofs_sb_info *, int __user *);
struct dentry *autofs4_expire_direct(struct super_block *sb,
				     struct vfsmount *mnt,
				     struct autofs_sb_info *sbi, int how);
struct dentry *autofs4_expire_indirect(struct super_block *sb,
				       struct vfsmount *mnt,
				       struct autofs_sb_info *sbi, int how);

/* Device node initialization */

int autofs_dev_ioctl_init(void);
void autofs_dev_ioctl_exit(void);

/* Operations structures */

extern const struct inode_operations autofs4_symlink_inode_operations;
extern const struct inode_operations autofs4_dir_inode_operations;
extern const struct file_operations autofs4_dir_operations;
extern const struct file_operations autofs4_root_operations;
extern const struct dentry_operations autofs4_dentry_operations;

/* VFS automount flags management functions */
static inline void __managed_dentry_set_managed(struct dentry *dentry)
{
	dentry->d_flags |= (DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT);
}

static inline void managed_dentry_set_managed(struct dentry *dentry)
{
	spin_lock(&dentry->d_lock);
	__managed_dentry_set_managed(dentry);
	spin_unlock(&dentry->d_lock);
}

static inline void __managed_dentry_clear_managed(struct dentry *dentry)
{
	dentry->d_flags &= ~(DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT);
}

static inline void managed_dentry_clear_managed(struct dentry *dentry)
{
	spin_lock(&dentry->d_lock);
	__managed_dentry_clear_managed(dentry);
	spin_unlock(&dentry->d_lock);
}

/* Initializing function */

int autofs4_fill_super(struct super_block *, void *, int);
struct autofs_info *autofs4_new_ino(struct autofs_sb_info *);
void autofs4_clean_ino(struct autofs_info *);

static inline int autofs_prepare_pipe(struct file *pipe)
{
	if (!pipe->f_op->write)
		return -EINVAL;
	if (!S_ISFIFO(file_inode(pipe)->i_mode))
		return -EINVAL;
	/* We want a packet pipe */
	pipe->f_flags |= O_DIRECT;
	return 0;
}

/* Queue management functions */

int autofs4_wait(struct autofs_sb_info *,struct dentry *, enum autofs_notify);
int autofs4_wait_release(struct autofs_sb_info *,autofs_wqt_t,int);
void autofs4_catatonic_mode(struct autofs_sb_info *);

static inline u32 autofs4_get_dev(struct autofs_sb_info *sbi)
{
	return new_encode_dev(sbi->sb->s_dev);
}

static inline u64 autofs4_get_ino(struct autofs_sb_info *sbi)
{
	return sbi->sb->s_root->d_inode->i_ino;
}

static inline int simple_positive(struct dentry *dentry)
{
	return dentry->d_inode && !d_unhashed(dentry);
}

static inline void __autofs4_add_expiring(struct dentry *dentry)
{
	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
	struct autofs_info *ino = autofs4_dentry_ino(dentry);
	if (ino) {
		if (list_empty(&ino->expiring))
			list_add(&ino->expiring, &sbi->expiring_list);
	}
	return;
}

static inline void autofs4_add_expiring(struct dentry *dentry)
{
	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
	struct autofs_info *ino = autofs4_dentry_ino(dentry);
	if (ino) {
		spin_lock(&sbi->lookup_lock);
		if (list_empty(&ino->expiring))
			list_add(&ino->expiring, &sbi->expiring_list);
		spin_unlock(&sbi->lookup_lock);
	}
	return;
}

static inline void autofs4_del_expiring(struct dentry *dentry)
{
	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
	struct autofs_info *ino = autofs4_dentry_ino(dentry);
	if (ino) {
		spin_lock(&sbi->lookup_lock);
		if (!list_empty(&ino->expiring))
			list_del_init(&ino->expiring);
		spin_unlock(&sbi->lookup_lock);
	}
	return;
}

extern void autofs4_kill_sb(struct super_block *);
Commit	Line	Data
1da177e4 LT	1	/* -- c -- ------------------------------------------------------------- *
	2	*
	3	* linux/fs/autofs/autofs_i.h
	4	*
	5	* Copyright 1997-1998 Transmeta Corporation - All Rights Reserved
34ca959c	6	* Copyright 2005-2006 Ian Kent <raven@themaw.net>
1da177e4 LT	7	*
	8	* This file is part of the Linux kernel and is made available under
	9	* the terms of the GNU General Public License, version 2, or at your
	10	* option, any later version, incorporated herein by reference.
	11	*
	12	* ----------------------------------------------------------------------- */
	13
	14	/* Internal header file for autofs */
	15
	16	#include <linux/auto_fs4.h>
8d7b48e0	17	#include <linux/auto_dev-ioctl.h>
1d5599e3	18	#include <linux/mutex.h>
b5c84bf6	19	#include <linux/spinlock.h>
1da177e4 LT	20	#include <linux/list.h>
	21
	22	/* This is the range of ioctl() numbers we claim as ours */
	23	#define AUTOFS_IOC_FIRST AUTOFS_IOC_READY
	24	#define AUTOFS_IOC_COUNT 32
	25
8d7b48e0 IK	26	#define AUTOFS_DEV_IOCTL_IOC_FIRST (AUTOFS_DEV_IOCTL_VERSION)
	27	#define AUTOFS_DEV_IOCTL_IOC_COUNT (AUTOFS_IOC_COUNT - 11)
	28
1da177e4 LT	29	#include <linux/kernel.h>
	30	#include <linux/slab.h>
	31	#include <linux/time.h>
	32	#include <linux/string.h>
	33	#include <linux/wait.h>
	34	#include <linux/sched.h>
	35	#include <linux/mount.h>
	36	#include <linux/namei.h>
	37	#include <asm/current.h>
	38	#include <asm/uaccess.h>
	39
	40	/* #define DEBUG */
	41
c3ad9962 LT	42	#define DPRINTK(fmt, ...) \
	43	pr_debug("pid %d: %s: " fmt "\n", \
	44	current->pid, __func__, ##__VA_ARGS__)
1da177e4	45
c3ad9962	46	#define AUTOFS_WARN(fmt, ...) \
8d7b48e0	47	printk(KERN_WARNING "pid %d: %s: " fmt "\n", \
c3ad9962	48	current->pid, __func__, ##__VA_ARGS__)
8d7b48e0	49
c3ad9962	50	#define AUTOFS_ERROR(fmt, ...) \
8d7b48e0	51	printk(KERN_ERR "pid %d: %s: " fmt "\n", \
c3ad9962	52	current->pid, __func__, ##__VA_ARGS__)
8d7b48e0	53
1da177e4 LT	54	/* Unified info structure. This is pointed to by both the dentry and
	55	inode structures. Each file in the filesystem has an instance of this
	56	structure. It holds a reference to the dentry, so dentries are never
	57	flushed while the file exists. All name lookups are dealt with at the
	58	dentry level, although the filesystem can interfere in the validation
	59	process. Readdir is implemented by traversing the dentry lists. */
	60	struct autofs_info {
	61	struct dentry *dentry;
	62	struct inode *inode;
	63
	64	int flags;
	65
6e60a9ab IK	66	struct completion expire_complete;
6e60a9ab IK	67
25767378	68	struct list_head active;
4f8427d1 IK	69	int active_count;
4f8427d1 IK	70
5f6f4f28	71	struct list_head expiring;
f50b6f86	72
1da177e4 LT	73	struct autofs_sb_info *sbi;
1da177e4 LT	74	unsigned long last_used;
1aff3c8b	75	atomic_t count;
1da177e4	76
45634cd8 EB	77	kuid_t uid;
45634cd8 EB	78	kgid_t gid;
1da177e4 LT	79	};
	80
	81	#define AUTOFS_INF_EXPIRING (1<<0) /* dentry is in the process of expiring */
aa952eb2	82	#define AUTOFS_INF_PENDING (1<<2) /* dentry pending mount */
1da177e4 LT	83
	84	struct autofs_wait_queue {
	85	wait_queue_head_t queue;
	86	struct autofs_wait_queue *next;
	87	autofs_wqt_t wait_queue_token;
	88	/* We use the following to see what we are waiting for */
70b52a0a	89	struct qstr name;
5c0a32fc IK	90	u32 dev;
5c0a32fc IK	91	u64 ino;
45634cd8 EB	92	kuid_t uid;
45634cd8 EB	93	kgid_t gid;
5c0a32fc IK	94	pid_t pid;
5c0a32fc IK	95	pid_t tgid;
1da177e4 LT	96	/* This is for status reporting upon return */
1da177e4 LT	97	int status;
296f7bf7	98	unsigned int wait_ctr;
1da177e4 LT	99	};
	100
	101	#define AUTOFS_SBI_MAGIC 0x6d4a556d
	102
	103	struct autofs_sb_info {
	104	u32 magic;
d7c4a5f1	105	int pipefd;
1da177e4	106	struct file *pipe;
6eaba35b	107	struct pid *oz_pgrp;
1da177e4 LT	108	int catatonic;
	109	int version;
	110	int sub_version;
d7c4a5f1 IK	111	int min_proto;
d7c4a5f1 IK	112	int max_proto;
1da177e4	113	unsigned long exp_timeout;
34ca959c	114	unsigned int type;
1da177e4 LT	115	int reghost_enabled;
	116	int needs_reghost;
	117	struct super_block *sb;
1d5599e3	118	struct mutex wq_mutex;
d668dc56	119	struct mutex pipe_mutex;
3a9720ce	120	spinlock_t fs_lock;
1da177e4	121	struct autofs_wait_queue queues; / Wait queue pointer */
5f6f4f28	122	spinlock_t lookup_lock;
25767378	123	struct list_head active_list;
5f6f4f28	124	struct list_head expiring_list;
baa40671	125	struct rcu_head rcu;
1da177e4 LT	126	};
	127
	128	static inline struct autofs_sb_info autofs4_sbi(struct super_block sb)
	129	{
	130	return (struct autofs_sb_info *)(sb->s_fs_info);
	131	}
	132
	133	static inline struct autofs_info autofs4_dentry_ino(struct dentry dentry)
	134	{
	135	return (struct autofs_info *)(dentry->d_fsdata);
	136	}
	137
	138	/* autofs4_oz_mode(): do we see the man behind the curtain? (The
	139	processes which do manipulations for us in user space sees the raw
	140	filesystem without "magic".) */
	141
	142	static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) {
6eaba35b	143	return sbi->catatonic \|\| task_pgrp(current) == sbi->oz_pgrp;
1da177e4 LT	144	}
1da177e4 LT	145
030a8ba4	146	struct inode autofs4_get_inode(struct super_block , umode_t);
1da177e4 LT	147	void autofs4_free_ino(struct autofs_info *);
	148
	149	/* Expiration */
	150	int is_autofs4_dentry(struct dentry *);
23bfc2a2	151	int autofs4_expire_wait(struct dentry *dentry, int rcu_walk);
1da177e4 LT	152	int autofs4_expire_run(struct super_block , struct vfsmount ,
	153	struct autofs_sb_info *,
	154	struct autofs_packet_expire __user *);
56fcef75 IK	155	int autofs4_do_expire_multi(struct super_block sb, struct vfsmount mnt,
56fcef75 IK	156	struct autofs_sb_info *sbi, int when);
1da177e4 LT	157	int autofs4_expire_multi(struct super_block , struct vfsmount ,
1da177e4 LT	158	struct autofs_sb_info , int __user );
8d7b48e0 IK	159	struct dentry autofs4_expire_direct(struct super_block sb,
	160	struct vfsmount *mnt,
	161	struct autofs_sb_info *sbi, int how);
	162	struct dentry autofs4_expire_indirect(struct super_block sb,
	163	struct vfsmount *mnt,
	164	struct autofs_sb_info *sbi, int how);
	165
	166	/* Device node initialization */
	167
	168	int autofs_dev_ioctl_init(void);
	169	void autofs_dev_ioctl_exit(void);
1da177e4 LT	170
	171	/* Operations structures */
	172
754661f1 AV	173	extern const struct inode_operations autofs4_symlink_inode_operations;
754661f1 AV	174	extern const struct inode_operations autofs4_dir_inode_operations;
4b6f5d20 AV	175	extern const struct file_operations autofs4_dir_operations;
4b6f5d20 AV	176	extern const struct file_operations autofs4_root_operations;
71e469db	177	extern const struct dentry_operations autofs4_dentry_operations;
10584211 IK	178
10584211 IK	179	/* VFS automount flags management functions */
b5b80177 IK	180	static inline void __managed_dentry_set_managed(struct dentry *dentry)
	181	{
	182	dentry->d_flags \|= (DCACHE_NEED_AUTOMOUNT\|DCACHE_MANAGE_TRANSIT);
	183	}
	184
	185	static inline void managed_dentry_set_managed(struct dentry *dentry)
	186	{
	187	spin_lock(&dentry->d_lock);
	188	__managed_dentry_set_managed(dentry);
	189	spin_unlock(&dentry->d_lock);
	190	}
	191
	192	static inline void __managed_dentry_clear_managed(struct dentry *dentry)
	193	{
	194	dentry->d_flags &= ~(DCACHE_NEED_AUTOMOUNT\|DCACHE_MANAGE_TRANSIT);
	195	}
	196
	197	static inline void managed_dentry_clear_managed(struct dentry *dentry)
	198	{
	199	spin_lock(&dentry->d_lock);
	200	__managed_dentry_clear_managed(dentry);
	201	spin_unlock(&dentry->d_lock);
	202	}
	203
1da177e4 LT	204	/* Initializing function */
	205
	206	int autofs4_fill_super(struct super_block , void , int);
26e6c910 AV	207	struct autofs_info autofs4_new_ino(struct autofs_sb_info );
26e6c910 AV	208	void autofs4_clean_ino(struct autofs_info *);
1da177e4	209
64f371bc LT	210	static inline int autofs_prepare_pipe(struct file *pipe)
64f371bc LT	211	{
72c2d531	212	if (!pipe->f_op->write)
64f371bc	213	return -EINVAL;
496ad9aa	214	if (!S_ISFIFO(file_inode(pipe)->i_mode))
64f371bc LT	215	return -EINVAL;
	216	/* We want a packet pipe */
	217	pipe->f_flags \|= O_DIRECT;
	218	return 0;
	219	}
	220
1da177e4 LT	221	/* Queue management functions */
1da177e4 LT	222
1da177e4 LT	223	int autofs4_wait(struct autofs_sb_info ,struct dentry , enum autofs_notify);
	224	int autofs4_wait_release(struct autofs_sb_info *,autofs_wqt_t,int);
	225	void autofs4_catatonic_mode(struct autofs_sb_info *);
	226
5c0a32fc IK	227	static inline u32 autofs4_get_dev(struct autofs_sb_info *sbi)
	228	{
	229	return new_encode_dev(sbi->sb->s_dev);
	230	}
	231
	232	static inline u64 autofs4_get_ino(struct autofs_sb_info *sbi)
	233	{
	234	return sbi->sb->s_root->d_inode->i_ino;
	235	}
	236
1da177e4 LT	237	static inline int simple_positive(struct dentry *dentry)
	238	{
	239	return dentry->d_inode && !d_unhashed(dentry);
	240	}
	241
2fd6b7f5 NP	242	static inline void __autofs4_add_expiring(struct dentry *dentry)
	243	{
	244	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
	245	struct autofs_info *ino = autofs4_dentry_ino(dentry);
	246	if (ino) {
	247	if (list_empty(&ino->expiring))
	248	list_add(&ino->expiring, &sbi->expiring_list);
	249	}
	250	return;
	251	}
	252
c4cd70b3 IK	253	static inline void autofs4_add_expiring(struct dentry *dentry)
	254	{
	255	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
	256	struct autofs_info *ino = autofs4_dentry_ino(dentry);
	257	if (ino) {
	258	spin_lock(&sbi->lookup_lock);
	259	if (list_empty(&ino->expiring))
	260	list_add(&ino->expiring, &sbi->expiring_list);
	261	spin_unlock(&sbi->lookup_lock);
	262	}
	263	return;
	264	}
	265
	266	static inline void autofs4_del_expiring(struct dentry *dentry)
	267	{
	268	struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
	269	struct autofs_info *ino = autofs4_dentry_ino(dentry);
	270	if (ino) {
	271	spin_lock(&sbi->lookup_lock);
	272	if (!list_empty(&ino->expiring))
	273	list_del_init(&ino->expiring);
	274	spin_unlock(&sbi->lookup_lock);
	275	}
	276	return;
	277	}
	278
6ce31523	279	extern void autofs4_kill_sb(struct super_block *);