[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)

#define AUTOFS_TYPE_TRIGGER	(AUTOFS_TYPE_DIRECT|AUTOFS_TYPE_OFFSET)

#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_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 vfsmount **mnt, struct dentry **dentry)
{
	int res = 0;

	while (d_mountpoint(*dentry)) {
		int followed = follow_down(mnt, dentry);
		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
bb979d7f IK	28	#define AUTOFS_TYPE_TRIGGER (AUTOFS_TYPE_DIRECT\|AUTOFS_TYPE_OFFSET)
bb979d7f IK	29
1da177e4 LT	30	#include <linux/kernel.h>
	31	#include <linux/slab.h>
	32	#include <linux/time.h>
	33	#include <linux/string.h>
	34	#include <linux/wait.h>
	35	#include <linux/sched.h>
	36	#include <linux/mount.h>
	37	#include <linux/namei.h>
	38	#include <asm/current.h>
	39	#include <asm/uaccess.h>
	40
	41	/* #define DEBUG */
	42
	43	#ifdef DEBUG
8d7b48e0 IK	44	#define DPRINTK(fmt, args...) \
	45	do { \
	46	printk(KERN_DEBUG "pid %d: %s: " fmt "\n", \
	47	current->pid, __func__, ##args); \
	48	} while (0)
1da177e4	49	#else
8d7b48e0	50	#define DPRINTK(fmt, args...) do {} while (0)
1da177e4 LT	51	#endif
1da177e4 LT	52
8d7b48e0 IK	53	#define AUTOFS_WARN(fmt, args...) \
	54	do { \
	55	printk(KERN_WARNING "pid %d: %s: " fmt "\n", \
	56	current->pid, __func__, ##args); \
	57	} while (0)
	58
	59	#define AUTOFS_ERROR(fmt, args...) \
	60	do { \
	61	printk(KERN_ERR "pid %d: %s: " fmt "\n", \
	62	current->pid, __func__, ##args); \
	63	} while (0)
	64
1da177e4 LT	65	/* Unified info structure. This is pointed to by both the dentry and
	66	inode structures. Each file in the filesystem has an instance of this
	67	structure. It holds a reference to the dentry, so dentries are never
	68	flushed while the file exists. All name lookups are dealt with at the
	69	dentry level, although the filesystem can interfere in the validation
	70	process. Readdir is implemented by traversing the dentry lists. */
	71	struct autofs_info {
	72	struct dentry *dentry;
	73	struct inode *inode;
	74
	75	int flags;
	76
6e60a9ab IK	77	struct completion expire_complete;
6e60a9ab IK	78
25767378	79	struct list_head active;
5f6f4f28	80	struct list_head expiring;
f50b6f86	81
1da177e4 LT	82	struct autofs_sb_info *sbi;
1da177e4 LT	83	unsigned long last_used;
1aff3c8b	84	atomic_t count;
1da177e4	85
c0f54d3e IK	86	uid_t uid;
	87	gid_t gid;
	88
1da177e4 LT	89	mode_t mode;
	90	size_t size;
	91
	92	void (free)(struct autofs_info );
	93	union {
	94	const char *symlink;
	95	} u;
	96	};
	97
	98	#define AUTOFS_INF_EXPIRING (1<<0) /* dentry is in the process of expiring */
6e60a9ab	99	#define AUTOFS_INF_MOUNTPOINT (1<<1) /* mountpoint status for direct expire */
1da177e4 LT	100
	101	struct autofs_wait_queue {
	102	wait_queue_head_t queue;
	103	struct autofs_wait_queue *next;
	104	autofs_wqt_t wait_queue_token;
	105	/* We use the following to see what we are waiting for */
70b52a0a	106	struct qstr name;
5c0a32fc IK	107	u32 dev;
	108	u64 ino;
	109	uid_t uid;
	110	gid_t gid;
	111	pid_t pid;
	112	pid_t tgid;
1da177e4 LT	113	/* This is for status reporting upon return */
1da177e4 LT	114	int status;
296f7bf7	115	unsigned int wait_ctr;
1da177e4 LT	116	};
	117
	118	#define AUTOFS_SBI_MAGIC 0x6d4a556d
	119
	120	struct autofs_sb_info {
	121	u32 magic;
d7c4a5f1	122	int pipefd;
1da177e4 LT	123	struct file *pipe;
	124	pid_t oz_pgrp;
	125	int catatonic;
	126	int version;
	127	int sub_version;
d7c4a5f1 IK	128	int min_proto;
d7c4a5f1 IK	129	int max_proto;
1da177e4	130	unsigned long exp_timeout;
34ca959c	131	unsigned int type;
1da177e4 LT	132	int reghost_enabled;
	133	int needs_reghost;
	134	struct super_block *sb;
1d5599e3	135	struct mutex wq_mutex;
3a9720ce	136	spinlock_t fs_lock;
1da177e4	137	struct autofs_wait_queue queues; / Wait queue pointer */
5f6f4f28	138	spinlock_t lookup_lock;
25767378	139	struct list_head active_list;
5f6f4f28	140	struct list_head expiring_list;
1da177e4 LT	141	};
	142
	143	static inline struct autofs_sb_info autofs4_sbi(struct super_block sb)
	144	{
	145	return (struct autofs_sb_info *)(sb->s_fs_info);
	146	}
	147
	148	static inline struct autofs_info autofs4_dentry_ino(struct dentry dentry)
	149	{
	150	return (struct autofs_info *)(dentry->d_fsdata);
	151	}
	152
	153	/* autofs4_oz_mode(): do we see the man behind the curtain? (The
	154	processes which do manipulations for us in user space sees the raw
	155	filesystem without "magic".) */
	156
	157	static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) {
a47afb0f	158	return sbi->catatonic \|\| task_pgrp_nr(current) == sbi->oz_pgrp;
1da177e4 LT	159	}
	160
	161	/* Does a dentry have some pending activity? */
	162	static inline int autofs4_ispending(struct dentry *dentry)
	163	{
	164	struct autofs_info *inf = autofs4_dentry_ino(dentry);
	165
3a9720ce IK	166	if (dentry->d_flags & DCACHE_AUTOFS_PENDING)
	167	return 1;
	168
97e7449a IK	169	if (inf->flags & AUTOFS_INF_EXPIRING)
97e7449a IK	170	return 1;
3a9720ce	171
97e7449a	172	return 0;
1da177e4 LT	173	}
	174
	175	static inline void autofs4_copy_atime(struct file src, struct file dst)
	176	{
a4669ed8 JJS	177	dst->f_path.dentry->d_inode->i_atime =
a4669ed8 JJS	178	src->f_path.dentry->d_inode->i_atime;
1da177e4 LT	179	return;
	180	}
	181
	182	struct inode autofs4_get_inode(struct super_block , struct autofs_info *);
	183	void autofs4_free_ino(struct autofs_info *);
	184
	185	/* Expiration */
	186	int is_autofs4_dentry(struct dentry *);
06a35985	187	int autofs4_expire_wait(struct dentry *dentry);
1da177e4 LT	188	int autofs4_expire_run(struct super_block , struct vfsmount ,
	189	struct autofs_sb_info *,
	190	struct autofs_packet_expire __user *);
	191	int autofs4_expire_multi(struct super_block , struct vfsmount ,
	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
9b1e3afd IK	226	static inline int autofs4_follow_mount(struct vfsmount mnt, struct dentry dentry)
	227	{
	228	int res = 0;
	229
	230	while (d_mountpoint(*dentry)) {
	231	int followed = follow_down(mnt, dentry);
	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 *);