[deliverable/linux.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/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 */

#ifdef DEBUG
#define DPRINTK(fmt, args...)				\
do {							\
	printk(KERN_DEBUG "pid %d: %s: " fmt "\n",	\
		current->pid, __func__, ##args);	\
} while (0)
#else
#define DPRINTK(fmt, args...) do {} while (0)
#endif

#define AUTOFS_WARN(fmt, args...)			\
do {							\
	printk(KERN_WARNING "pid %d: %s: " fmt "\n",	\
		current->pid, __func__, ##args);	\
} while (0)

#define AUTOFS_ERROR(fmt, args...)			\
do {							\
	printk(KERN_ERR "pid %d: %s: " fmt "\n",	\
		current->pid, __func__, ##args);	\
} while (0)

/* 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;
	struct list_head expiring;

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

	uid_t uid;
	gid_t gid;

	mode_t	mode;
	size_t	size;

	void (*free)(struct autofs_info *);
	union {
		const char *symlink;
	} u;
};

#define AUTOFS_INF_EXPIRING	(1<<0) /* dentry is in the process of expiring */
#define AUTOFS_INF_MOUNTPOINT	(1<<1) /* mountpoint status for direct expire */

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;
	uid_t uid;
	gid_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;
	pid_t 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;
	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;
};

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_nr(current) == sbi->oz_pgrp;
}

/* Does a dentry have some pending activity? */
static inline int autofs4_ispending(struct dentry *dentry)
{
	struct autofs_info *inf = autofs4_dentry_ino(dentry);

	if (dentry->d_flags & DCACHE_AUTOFS_PENDING)
		return 1;

	if (inf->flags & AUTOFS_INF_EXPIRING)
		return 1;

	return 0;
}

static inline void autofs4_copy_atime(struct file *src, struct file *dst)
{
	dst->f_path.dentry->d_inode->i_atime =
		src->f_path.dentry->d_inode->i_atime;
	return;
}

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

/* Expiration */
int is_autofs4_dentry(struct dentry *);
int autofs4_expire_wait(struct dentry *dentry);
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 inode_operations autofs4_root_inode_operations;
extern const struct inode_operations autofs4_indirect_root_inode_operations;
extern const struct inode_operations autofs4_direct_root_inode_operations;
extern const struct file_operations autofs4_dir_operations;
extern const struct file_operations autofs4_root_operations;

/* Initializing function */

int autofs4_fill_super(struct super_block *, void *, int);
struct autofs_info *autofs4_init_ino(struct autofs_info *, struct autofs_sb_info *sbi, mode_t mode);

/* 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 int autofs4_follow_mount(struct path *path)
{
	int res = 0;

	while (d_mountpoint(path->dentry)) {
		int followed = follow_down(path);
		if (!followed)
			break;
		res = 1;
	}
	return res;
}

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 int __simple_empty(struct dentry *dentry)
{
	struct dentry *child;
	int ret = 0;

	list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child)
		if (simple_positive(child))
			goto out;
	ret = 1;
out:
	return ret;
}

void autofs4_dentry_release(struct dentry *);
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>
1da177e4 LT	19	#include <linux/list.h>
	20
	21	/* This is the range of ioctl() numbers we claim as ours */
	22	#define AUTOFS_IOC_FIRST AUTOFS_IOC_READY
	23	#define AUTOFS_IOC_COUNT 32
	24
8d7b48e0 IK	25	#define AUTOFS_DEV_IOCTL_IOC_FIRST (AUTOFS_DEV_IOCTL_VERSION)
	26	#define AUTOFS_DEV_IOCTL_IOC_COUNT (AUTOFS_IOC_COUNT - 11)
	27
1da177e4 LT	28	#include <linux/kernel.h>
	29	#include <linux/slab.h>
	30	#include <linux/time.h>
	31	#include <linux/string.h>
	32	#include <linux/wait.h>
	33	#include <linux/sched.h>
	34	#include <linux/mount.h>
	35	#include <linux/namei.h>
	36	#include <asm/current.h>
	37	#include <asm/uaccess.h>
	38
	39	/* #define DEBUG */
	40
	41	#ifdef DEBUG
8d7b48e0 IK	42	#define DPRINTK(fmt, args...) \
	43	do { \
	44	printk(KERN_DEBUG "pid %d: %s: " fmt "\n", \
	45	current->pid, __func__, ##args); \
	46	} while (0)
1da177e4	47	#else
8d7b48e0	48	#define DPRINTK(fmt, args...) do {} while (0)
1da177e4 LT	49	#endif
1da177e4 LT	50
8d7b48e0 IK	51	#define AUTOFS_WARN(fmt, args...) \
	52	do { \
	53	printk(KERN_WARNING "pid %d: %s: " fmt "\n", \
	54	current->pid, __func__, ##args); \
	55	} while (0)
	56
	57	#define AUTOFS_ERROR(fmt, args...) \
	58	do { \
	59	printk(KERN_ERR "pid %d: %s: " fmt "\n", \
	60	current->pid, __func__, ##args); \
	61	} while (0)
	62
1da177e4 LT	63	/* Unified info structure. This is pointed to by both the dentry and
	64	inode structures. Each file in the filesystem has an instance of this
	65	structure. It holds a reference to the dentry, so dentries are never
	66	flushed while the file exists. All name lookups are dealt with at the
	67	dentry level, although the filesystem can interfere in the validation
	68	process. Readdir is implemented by traversing the dentry lists. */
	69	struct autofs_info {
	70	struct dentry *dentry;
	71	struct inode *inode;
	72
	73	int flags;
	74
6e60a9ab IK	75	struct completion expire_complete;
6e60a9ab IK	76
25767378	77	struct list_head active;
5f6f4f28	78	struct list_head expiring;
f50b6f86	79
1da177e4 LT	80	struct autofs_sb_info *sbi;
1da177e4 LT	81	unsigned long last_used;
1aff3c8b	82	atomic_t count;
1da177e4	83
c0f54d3e IK	84	uid_t uid;
	85	gid_t gid;
	86
1da177e4 LT	87	mode_t mode;
	88	size_t size;
	89
	90	void (free)(struct autofs_info );
	91	union {
	92	const char *symlink;
	93	} u;
	94	};
	95
	96	#define AUTOFS_INF_EXPIRING (1<<0) /* dentry is in the process of expiring */
6e60a9ab	97	#define AUTOFS_INF_MOUNTPOINT (1<<1) /* mountpoint status for direct expire */
1da177e4 LT	98
	99	struct autofs_wait_queue {
	100	wait_queue_head_t queue;
	101	struct autofs_wait_queue *next;
	102	autofs_wqt_t wait_queue_token;
	103	/* We use the following to see what we are waiting for */
70b52a0a	104	struct qstr name;
5c0a32fc IK	105	u32 dev;
	106	u64 ino;
	107	uid_t uid;
	108	gid_t gid;
	109	pid_t pid;
	110	pid_t tgid;
1da177e4 LT	111	/* This is for status reporting upon return */
1da177e4 LT	112	int status;
296f7bf7	113	unsigned int wait_ctr;
1da177e4 LT	114	};
	115
	116	#define AUTOFS_SBI_MAGIC 0x6d4a556d
	117
	118	struct autofs_sb_info {
	119	u32 magic;
d7c4a5f1	120	int pipefd;
1da177e4 LT	121	struct file *pipe;
	122	pid_t oz_pgrp;
	123	int catatonic;
	124	int version;
	125	int sub_version;
d7c4a5f1 IK	126	int min_proto;
d7c4a5f1 IK	127	int max_proto;
1da177e4	128	unsigned long exp_timeout;
34ca959c	129	unsigned int type;
1da177e4 LT	130	int reghost_enabled;
	131	int needs_reghost;
	132	struct super_block *sb;
1d5599e3	133	struct mutex wq_mutex;
3a9720ce	134	spinlock_t fs_lock;
1da177e4	135	struct autofs_wait_queue queues; / Wait queue pointer */
5f6f4f28	136	spinlock_t lookup_lock;
25767378	137	struct list_head active_list;
5f6f4f28	138	struct list_head expiring_list;
1da177e4 LT	139	};
	140
	141	static inline struct autofs_sb_info autofs4_sbi(struct super_block sb)
	142	{
	143	return (struct autofs_sb_info *)(sb->s_fs_info);
	144	}
	145
	146	static inline struct autofs_info autofs4_dentry_ino(struct dentry dentry)
	147	{
	148	return (struct autofs_info *)(dentry->d_fsdata);
	149	}
	150
	151	/* autofs4_oz_mode(): do we see the man behind the curtain? (The
	152	processes which do manipulations for us in user space sees the raw
	153	filesystem without "magic".) */
	154
	155	static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) {
a47afb0f	156	return sbi->catatonic \|\| task_pgrp_nr(current) == sbi->oz_pgrp;
1da177e4 LT	157	}
	158
	159	/* Does a dentry have some pending activity? */
	160	static inline int autofs4_ispending(struct dentry *dentry)
	161	{
	162	struct autofs_info *inf = autofs4_dentry_ino(dentry);
	163
3a9720ce IK	164	if (dentry->d_flags & DCACHE_AUTOFS_PENDING)
	165	return 1;
	166
97e7449a IK	167	if (inf->flags & AUTOFS_INF_EXPIRING)
97e7449a IK	168	return 1;
3a9720ce	169
97e7449a	170	return 0;
1da177e4 LT	171	}
	172
	173	static inline void autofs4_copy_atime(struct file src, struct file dst)
	174	{
a4669ed8 JJS	175	dst->f_path.dentry->d_inode->i_atime =
a4669ed8 JJS	176	src->f_path.dentry->d_inode->i_atime;
1da177e4 LT	177	return;
	178	}
	179
	180	struct inode autofs4_get_inode(struct super_block , struct autofs_info *);
	181	void autofs4_free_ino(struct autofs_info *);
	182
	183	/* Expiration */
	184	int is_autofs4_dentry(struct dentry *);
06a35985	185	int autofs4_expire_wait(struct dentry *dentry);
1da177e4 LT	186	int autofs4_expire_run(struct super_block , struct vfsmount ,
	187	struct autofs_sb_info *,
	188	struct autofs_packet_expire __user *);
56fcef75 IK	189	int autofs4_do_expire_multi(struct super_block sb, struct vfsmount mnt,
56fcef75 IK	190	struct autofs_sb_info *sbi, int when);
1da177e4 LT	191	int autofs4_expire_multi(struct super_block , struct vfsmount ,
1da177e4 LT	192	struct autofs_sb_info , int __user );
8d7b48e0 IK	193	struct dentry autofs4_expire_direct(struct super_block sb,
	194	struct vfsmount *mnt,
	195	struct autofs_sb_info *sbi, int how);
	196	struct dentry autofs4_expire_indirect(struct super_block sb,
	197	struct vfsmount *mnt,
	198	struct autofs_sb_info *sbi, int how);
	199
	200	/* Device node initialization */
	201
	202	int autofs_dev_ioctl_init(void);
	203	void autofs_dev_ioctl_exit(void);
1da177e4 LT	204
	205	/* Operations structures */
	206
754661f1 AV	207	extern const struct inode_operations autofs4_symlink_inode_operations;
	208	extern const struct inode_operations autofs4_dir_inode_operations;
	209	extern const struct inode_operations autofs4_root_inode_operations;
	210	extern const struct inode_operations autofs4_indirect_root_inode_operations;
	211	extern const struct inode_operations autofs4_direct_root_inode_operations;
4b6f5d20 AV	212	extern const struct file_operations autofs4_dir_operations;
4b6f5d20 AV	213	extern const struct file_operations autofs4_root_operations;
1da177e4 LT	214
	215	/* Initializing function */
	216
	217	int autofs4_fill_super(struct super_block , void , int);
	218	struct autofs_info autofs4_init_ino(struct autofs_info , struct autofs_sb_info *sbi, mode_t mode);
	219
	220	/* Queue management functions */
	221
1da177e4 LT	222	int autofs4_wait(struct autofs_sb_info ,struct dentry , enum autofs_notify);
	223	int autofs4_wait_release(struct autofs_sb_info *,autofs_wqt_t,int);
	224	void autofs4_catatonic_mode(struct autofs_sb_info *);
	225
9393bd07	226	static inline int autofs4_follow_mount(struct path *path)
9b1e3afd IK	227	{
	228	int res = 0;
	229
9393bd07 AV	230	while (d_mountpoint(path->dentry)) {
9393bd07 AV	231	int followed = follow_down(path);
9b1e3afd IK	232	if (!followed)
	233	break;
	234	res = 1;
	235	}
	236	return res;
	237	}
	238
5c0a32fc IK	239	static inline u32 autofs4_get_dev(struct autofs_sb_info *sbi)
	240	{
	241	return new_encode_dev(sbi->sb->s_dev);
	242	}
	243
	244	static inline u64 autofs4_get_ino(struct autofs_sb_info *sbi)
	245	{
	246	return sbi->sb->s_root->d_inode->i_ino;
	247	}
	248
1da177e4 LT	249	static inline int simple_positive(struct dentry *dentry)
	250	{
	251	return dentry->d_inode && !d_unhashed(dentry);
	252	}
	253
90a59c7c	254	static inline int __simple_empty(struct dentry *dentry)
1da177e4 LT	255	{
	256	struct dentry *child;
	257	int ret = 0;
	258
5160ee6f	259	list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child)
1da177e4 LT	260	if (simple_positive(child))
	261	goto out;
	262	ret = 1;
	263	out:
	264	return ret;
	265	}
f5b95ff0 AB	266
f5b95ff0 AB	267	void autofs4_dentry_release(struct dentry *);
6ce31523	268	extern void autofs4_kill_sb(struct super_block *);