[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/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

#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

/* 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;

	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

#define AUTOFS_TYPE_INDIRECT     0x0001
#define AUTOFS_TYPE_DIRECT       0x0002
#define AUTOFS_TYPE_OFFSET       0x0004

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 *);

/* 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>
1d5599e3	17	#include <linux/mutex.h>
1da177e4 LT	18	#include <linux/list.h>
	19
	20	/* This is the range of ioctl() numbers we claim as ours */
	21	#define AUTOFS_IOC_FIRST AUTOFS_IOC_READY
	22	#define AUTOFS_IOC_COUNT 32
	23
	24	#include <linux/kernel.h>
	25	#include <linux/slab.h>
	26	#include <linux/time.h>
	27	#include <linux/string.h>
	28	#include <linux/wait.h>
	29	#include <linux/sched.h>
	30	#include <linux/mount.h>
	31	#include <linux/namei.h>
	32	#include <asm/current.h>
	33	#include <asm/uaccess.h>
	34
	35	/* #define DEBUG */
	36
	37	#ifdef DEBUG
8e24eea7	38	#define DPRINTK(fmt,args...) do { printk(KERN_DEBUG "pid %d: %s: " fmt "\n" , current->pid , __func__ , ##args); } while(0)
1da177e4 LT	39	#else
	40	#define DPRINTK(fmt,args...) do {} while(0)
	41	#endif
	42
1da177e4 LT	43	/* Unified info structure. This is pointed to by both the dentry and
	44	inode structures. Each file in the filesystem has an instance of this
	45	structure. It holds a reference to the dentry, so dentries are never
	46	flushed while the file exists. All name lookups are dealt with at the
	47	dentry level, although the filesystem can interfere in the validation
	48	process. Readdir is implemented by traversing the dentry lists. */
	49	struct autofs_info {
	50	struct dentry *dentry;
	51	struct inode *inode;
	52
	53	int flags;
	54
6e60a9ab IK	55	struct completion expire_complete;
6e60a9ab IK	56
25767378	57	struct list_head active;
5f6f4f28	58	struct list_head expiring;
f50b6f86	59
1da177e4 LT	60	struct autofs_sb_info *sbi;
1da177e4 LT	61	unsigned long last_used;
1aff3c8b	62	atomic_t count;
1da177e4 LT	63
	64	mode_t mode;
	65	size_t size;
	66
	67	void (free)(struct autofs_info );
	68	union {
	69	const char *symlink;
	70	} u;
	71	};
	72
	73	#define AUTOFS_INF_EXPIRING (1<<0) /* dentry is in the process of expiring */
6e60a9ab	74	#define AUTOFS_INF_MOUNTPOINT (1<<1) /* mountpoint status for direct expire */
1da177e4 LT	75
	76	struct autofs_wait_queue {
	77	wait_queue_head_t queue;
	78	struct autofs_wait_queue *next;
	79	autofs_wqt_t wait_queue_token;
	80	/* We use the following to see what we are waiting for */
70b52a0a	81	struct qstr name;
5c0a32fc IK	82	u32 dev;
	83	u64 ino;
	84	uid_t uid;
	85	gid_t gid;
	86	pid_t pid;
	87	pid_t tgid;
1da177e4 LT	88	/* This is for status reporting upon return */
1da177e4 LT	89	int status;
296f7bf7	90	unsigned int wait_ctr;
1da177e4 LT	91	};
	92
	93	#define AUTOFS_SBI_MAGIC 0x6d4a556d
	94
44d53eb0 IK	95	#define AUTOFS_TYPE_INDIRECT 0x0001
	96	#define AUTOFS_TYPE_DIRECT 0x0002
	97	#define AUTOFS_TYPE_OFFSET 0x0004
34ca959c	98
1da177e4 LT	99	struct autofs_sb_info {
1da177e4 LT	100	u32 magic;
d7c4a5f1	101	int pipefd;
1da177e4 LT	102	struct file *pipe;
	103	pid_t oz_pgrp;
	104	int catatonic;
	105	int version;
	106	int sub_version;
d7c4a5f1 IK	107	int min_proto;
d7c4a5f1 IK	108	int max_proto;
1da177e4	109	unsigned long exp_timeout;
34ca959c	110	unsigned int type;
1da177e4 LT	111	int reghost_enabled;
	112	int needs_reghost;
	113	struct super_block *sb;
1d5599e3	114	struct mutex wq_mutex;
3a9720ce	115	spinlock_t fs_lock;
1da177e4	116	struct autofs_wait_queue queues; / Wait queue pointer */
5f6f4f28	117	spinlock_t lookup_lock;
25767378	118	struct list_head active_list;
5f6f4f28	119	struct list_head expiring_list;
1da177e4 LT	120	};
	121
	122	static inline struct autofs_sb_info autofs4_sbi(struct super_block sb)
	123	{
	124	return (struct autofs_sb_info *)(sb->s_fs_info);
	125	}
	126
	127	static inline struct autofs_info autofs4_dentry_ino(struct dentry dentry)
	128	{
	129	return (struct autofs_info *)(dentry->d_fsdata);
	130	}
	131
	132	/* autofs4_oz_mode(): do we see the man behind the curtain? (The
	133	processes which do manipulations for us in user space sees the raw
	134	filesystem without "magic".) */
	135
	136	static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) {
a47afb0f	137	return sbi->catatonic \|\| task_pgrp_nr(current) == sbi->oz_pgrp;
1da177e4 LT	138	}
	139
	140	/* Does a dentry have some pending activity? */
	141	static inline int autofs4_ispending(struct dentry *dentry)
	142	{
	143	struct autofs_info *inf = autofs4_dentry_ino(dentry);
	144
3a9720ce IK	145	if (dentry->d_flags & DCACHE_AUTOFS_PENDING)
	146	return 1;
	147
97e7449a IK	148	if (inf->flags & AUTOFS_INF_EXPIRING)
97e7449a IK	149	return 1;
3a9720ce	150
97e7449a	151	return 0;
1da177e4 LT	152	}
	153
	154	static inline void autofs4_copy_atime(struct file src, struct file dst)
	155	{
a4669ed8 JJS	156	dst->f_path.dentry->d_inode->i_atime =
a4669ed8 JJS	157	src->f_path.dentry->d_inode->i_atime;
1da177e4 LT	158	return;
	159	}
	160
	161	struct inode autofs4_get_inode(struct super_block , struct autofs_info *);
	162	void autofs4_free_ino(struct autofs_info *);
	163
	164	/* Expiration */
	165	int is_autofs4_dentry(struct dentry *);
06a35985	166	int autofs4_expire_wait(struct dentry *dentry);
1da177e4 LT	167	int autofs4_expire_run(struct super_block , struct vfsmount ,
	168	struct autofs_sb_info *,
	169	struct autofs_packet_expire __user *);
	170	int autofs4_expire_multi(struct super_block , struct vfsmount ,
	171	struct autofs_sb_info , int __user );
	172
	173	/* Operations structures */
	174
754661f1 AV	175	extern const struct inode_operations autofs4_symlink_inode_operations;
	176	extern const struct inode_operations autofs4_dir_inode_operations;
	177	extern const struct inode_operations autofs4_root_inode_operations;
	178	extern const struct inode_operations autofs4_indirect_root_inode_operations;
	179	extern const struct inode_operations autofs4_direct_root_inode_operations;
4b6f5d20 AV	180	extern const struct file_operations autofs4_dir_operations;
4b6f5d20 AV	181	extern const struct file_operations autofs4_root_operations;
1da177e4 LT	182
	183	/* Initializing function */
	184
	185	int autofs4_fill_super(struct super_block , void , int);
	186	struct autofs_info autofs4_init_ino(struct autofs_info , struct autofs_sb_info *sbi, mode_t mode);
	187
	188	/* Queue management functions */
	189
1da177e4 LT	190	int autofs4_wait(struct autofs_sb_info ,struct dentry , enum autofs_notify);
	191	int autofs4_wait_release(struct autofs_sb_info *,autofs_wqt_t,int);
	192	void autofs4_catatonic_mode(struct autofs_sb_info *);
	193
9b1e3afd IK	194	static inline int autofs4_follow_mount(struct vfsmount mnt, struct dentry dentry)
	195	{
	196	int res = 0;
	197
	198	while (d_mountpoint(*dentry)) {
	199	int followed = follow_down(mnt, dentry);
	200	if (!followed)
	201	break;
	202	res = 1;
	203	}
	204	return res;
	205	}
	206
5c0a32fc IK	207	static inline u32 autofs4_get_dev(struct autofs_sb_info *sbi)
	208	{
	209	return new_encode_dev(sbi->sb->s_dev);
	210	}
	211
	212	static inline u64 autofs4_get_ino(struct autofs_sb_info *sbi)
	213	{
	214	return sbi->sb->s_root->d_inode->i_ino;
	215	}
	216
1da177e4 LT	217	static inline int simple_positive(struct dentry *dentry)
	218	{
	219	return dentry->d_inode && !d_unhashed(dentry);
	220	}
	221
90a59c7c	222	static inline int __simple_empty(struct dentry *dentry)
1da177e4 LT	223	{
	224	struct dentry *child;
	225	int ret = 0;
	226
5160ee6f	227	list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child)
1da177e4 LT	228	if (simple_positive(child))
	229	goto out;
	230	ret = 1;
	231	out:
	232	return ret;
	233	}
f5b95ff0 AB	234
f5b95ff0 AB	235	void autofs4_dentry_release(struct dentry *);
6ce31523	236	extern void autofs4_kill_sb(struct super_block *);