[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 , __FUNCTION__ , ##args); } while(0)
#else
#define DPRINTK(fmt,args...) do {} while(0)
#endif

#define AUTOFS_SUPER_MAGIC 0x0187

/* 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 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 */

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 */
	int hash;
	int len;
	char *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;
	atomic_t notified;
	atomic_t 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;
	struct dentry *root;
	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 */
};

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 || process_group(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);
	int pending = 0;

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

	if (inf) {
		spin_lock(&inf->sbi->fs_lock);
		pending = inf->flags & AUTOFS_INF_EXPIRING;
		spin_unlock(&inf->sbi->fs_lock);
	}

	return pending;
}

static inline void autofs4_copy_atime(struct file *src, struct file *dst)
{
	dst->f_dentry->d_inode->i_atime = src->f_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_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 struct inode_operations autofs4_symlink_inode_operations;
extern struct inode_operations autofs4_dir_inode_operations;
extern struct inode_operations autofs4_root_inode_operations;
extern struct inode_operations autofs4_indirect_root_inode_operations;
extern struct inode_operations autofs4_direct_root_inode_operations;
extern struct file_operations autofs4_dir_operations;
extern 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;
}
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
	38	#define DPRINTK(fmt,args...) do { printk(KERN_DEBUG "pid %d: %s: " fmt "\n" , current->pid , __FUNCTION__ , ##args); } while(0)
	39	#else
	40	#define DPRINTK(fmt,args...) do {} while(0)
	41	#endif
	42
	43	#define AUTOFS_SUPER_MAGIC 0x0187
	44
1da177e4 LT	45	/* Unified info structure. This is pointed to by both the dentry and
	46	inode structures. Each file in the filesystem has an instance of this
	47	structure. It holds a reference to the dentry, so dentries are never
	48	flushed while the file exists. All name lookups are dealt with at the
	49	dentry level, although the filesystem can interfere in the validation
	50	process. Readdir is implemented by traversing the dentry lists. */
	51	struct autofs_info {
	52	struct dentry *dentry;
	53	struct inode *inode;
	54
	55	int flags;
	56
	57	struct autofs_sb_info *sbi;
	58	unsigned long last_used;
1aff3c8b	59	atomic_t count;
1da177e4 LT	60
	61	mode_t mode;
	62	size_t size;
	63
	64	void (free)(struct autofs_info );
	65	union {
	66	const char *symlink;
	67	} u;
	68	};
	69
	70	#define AUTOFS_INF_EXPIRING (1<<0) /* dentry is in the process of expiring */
	71
	72	struct autofs_wait_queue {
	73	wait_queue_head_t queue;
	74	struct autofs_wait_queue *next;
	75	autofs_wqt_t wait_queue_token;
	76	/* We use the following to see what we are waiting for */
	77	int hash;
	78	int len;
	79	char *name;
5c0a32fc IK	80	u32 dev;
	81	u64 ino;
	82	uid_t uid;
	83	gid_t gid;
	84	pid_t pid;
	85	pid_t tgid;
1da177e4 LT	86	/* This is for status reporting upon return */
1da177e4 LT	87	int status;
4dcd00b1	88	atomic_t notified;
1da177e4 LT	89	atomic_t wait_ctr;
	90	};
	91
	92	#define AUTOFS_SBI_MAGIC 0x6d4a556d
	93
44d53eb0 IK	94	#define AUTOFS_TYPE_INDIRECT 0x0001
	95	#define AUTOFS_TYPE_DIRECT 0x0002
	96	#define AUTOFS_TYPE_OFFSET 0x0004
34ca959c	97
1da177e4 LT	98	struct autofs_sb_info {
1da177e4 LT	99	u32 magic;
104e49fc	100	struct dentry *root;
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 LT	116	struct autofs_wait_queue queues; / Wait queue pointer */
	117	};
	118
	119	static inline struct autofs_sb_info autofs4_sbi(struct super_block sb)
	120	{
	121	return (struct autofs_sb_info *)(sb->s_fs_info);
	122	}
	123
	124	static inline struct autofs_info autofs4_dentry_ino(struct dentry dentry)
	125	{
	126	return (struct autofs_info *)(dentry->d_fsdata);
	127	}
	128
	129	/* autofs4_oz_mode(): do we see the man behind the curtain? (The
	130	processes which do manipulations for us in user space sees the raw
	131	filesystem without "magic".) */
	132
	133	static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) {
	134	return sbi->catatonic \|\| process_group(current) == sbi->oz_pgrp;
	135	}
	136
	137	/* Does a dentry have some pending activity? */
	138	static inline int autofs4_ispending(struct dentry *dentry)
	139	{
	140	struct autofs_info *inf = autofs4_dentry_ino(dentry);
3a9720ce	141	int pending = 0;
1da177e4	142
3a9720ce IK	143	if (dentry->d_flags & DCACHE_AUTOFS_PENDING)
	144	return 1;
	145
	146	if (inf) {
	147	spin_lock(&inf->sbi->fs_lock);
	148	pending = inf->flags & AUTOFS_INF_EXPIRING;
	149	spin_unlock(&inf->sbi->fs_lock);
	150	}
	151
	152	return pending;
1da177e4 LT	153	}
	154
	155	static inline void autofs4_copy_atime(struct file src, struct file dst)
	156	{
	157	dst->f_dentry->d_inode->i_atime = src->f_dentry->d_inode->i_atime;
	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 *);
	166	int autofs4_expire_run(struct super_block , struct vfsmount ,
	167	struct autofs_sb_info *,
	168	struct autofs_packet_expire __user *);
	169	int autofs4_expire_multi(struct super_block , struct vfsmount ,
	170	struct autofs_sb_info , int __user );
	171
	172	/* Operations structures */
	173
	174	extern struct inode_operations autofs4_symlink_inode_operations;
	175	extern struct inode_operations autofs4_dir_inode_operations;
	176	extern struct inode_operations autofs4_root_inode_operations;
34ca959c IK	177	extern struct inode_operations autofs4_indirect_root_inode_operations;
34ca959c IK	178	extern struct inode_operations autofs4_direct_root_inode_operations;
1da177e4 LT	179	extern struct file_operations autofs4_dir_operations;
	180	extern struct file_operations autofs4_root_operations;
	181
	182	/* Initializing function */
	183
	184	int autofs4_fill_super(struct super_block , void , int);
	185	struct autofs_info autofs4_init_ino(struct autofs_info , struct autofs_sb_info *sbi, mode_t mode);
	186
	187	/* Queue management functions */
	188
1da177e4 LT	189	int autofs4_wait(struct autofs_sb_info ,struct dentry , enum autofs_notify);
	190	int autofs4_wait_release(struct autofs_sb_info *,autofs_wqt_t,int);
	191	void autofs4_catatonic_mode(struct autofs_sb_info *);
	192
9b1e3afd IK	193	static inline int autofs4_follow_mount(struct vfsmount mnt, struct dentry dentry)
	194	{
	195	int res = 0;
	196
	197	while (d_mountpoint(*dentry)) {
	198	int followed = follow_down(mnt, dentry);
	199	if (!followed)
	200	break;
	201	res = 1;
	202	}
	203	return res;
	204	}
	205
5c0a32fc IK	206	static inline u32 autofs4_get_dev(struct autofs_sb_info *sbi)
	207	{
	208	return new_encode_dev(sbi->sb->s_dev);
	209	}
	210
	211	static inline u64 autofs4_get_ino(struct autofs_sb_info *sbi)
	212	{
	213	return sbi->sb->s_root->d_inode->i_ino;
	214	}
	215
1da177e4 LT	216	static inline int simple_positive(struct dentry *dentry)
	217	{
	218	return dentry->d_inode && !d_unhashed(dentry);
	219	}
	220
90a59c7c	221	static inline int __simple_empty(struct dentry *dentry)
1da177e4 LT	222	{
	223	struct dentry *child;
	224	int ret = 0;
	225
5160ee6f	226	list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child)
1da177e4 LT	227	if (simple_positive(child))
	228	goto out;
	229	ret = 1;
	230	out:
	231	return ret;
	232	}