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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* -*- c -*- ------------------------------------------------------------- *
2 *
3 * linux/fs/autofs/autofs_i.h
4 *
5 * Copyright 1997-1998 Transmeta Corporation - All Rights Reserved
Ian Kent34ca9592006-03-27 01:14:54 -08006 * Copyright 2005-2006 Ian Kent <raven@themaw.net>
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 *
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>
Ingo Molnar1d5599e2006-03-23 03:00:41 -080017#include <linux/mutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#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
Harvey Harrison8e24eea2008-04-30 00:55:09 -070038#define DPRINTK(fmt,args...) do { printk(KERN_DEBUG "pid %d: %s: " fmt "\n" , current->pid , __func__ , ##args); } while(0)
Linus Torvalds1da177e2005-04-16 15:20:36 -070039#else
40#define DPRINTK(fmt,args...) do {} while(0)
41#endif
42
Linus Torvalds1da177e2005-04-16 15:20:36 -070043/* 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. */
49struct autofs_info {
50 struct dentry *dentry;
51 struct inode *inode;
52
53 int flags;
54
Ian Kentf50b6f82007-02-20 13:58:10 -080055 struct list_head rehash;
56
Linus Torvalds1da177e2005-04-16 15:20:36 -070057 struct autofs_sb_info *sbi;
58 unsigned long last_used;
Ian Kent1aff3c82006-03-27 01:14:46 -080059 atomic_t count;
Linus Torvalds1da177e2005-04-16 15:20:36 -070060
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
72struct 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 */
Ian Kenta5370552006-05-15 09:43:51 -070077 unsigned int hash;
78 unsigned int len;
Linus Torvalds1da177e2005-04-16 15:20:36 -070079 char *name;
Ian Kent5c0a32f2006-03-27 01:14:55 -080080 u32 dev;
81 u64 ino;
82 uid_t uid;
83 gid_t gid;
84 pid_t pid;
85 pid_t tgid;
Linus Torvalds1da177e2005-04-16 15:20:36 -070086 /* This is for status reporting upon return */
87 int status;
Linus Torvalds1da177e2005-04-16 15:20:36 -070088 atomic_t wait_ctr;
89};
90
91#define AUTOFS_SBI_MAGIC 0x6d4a556d
92
Ian Kent44d53eb2006-03-27 01:14:56 -080093#define AUTOFS_TYPE_INDIRECT 0x0001
94#define AUTOFS_TYPE_DIRECT 0x0002
95#define AUTOFS_TYPE_OFFSET 0x0004
Ian Kent34ca9592006-03-27 01:14:54 -080096
Linus Torvalds1da177e2005-04-16 15:20:36 -070097struct autofs_sb_info {
98 u32 magic;
Ian Kentd7c4a5f2006-03-27 01:14:49 -080099 int pipefd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100 struct file *pipe;
101 pid_t oz_pgrp;
102 int catatonic;
103 int version;
104 int sub_version;
Ian Kentd7c4a5f2006-03-27 01:14:49 -0800105 int min_proto;
106 int max_proto;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 unsigned long exp_timeout;
Ian Kent34ca9592006-03-27 01:14:54 -0800108 unsigned int type;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109 int reghost_enabled;
110 int needs_reghost;
111 struct super_block *sb;
Ingo Molnar1d5599e2006-03-23 03:00:41 -0800112 struct mutex wq_mutex;
Ian Kent3a9720c2005-05-01 08:59:17 -0700113 spinlock_t fs_lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114 struct autofs_wait_queue *queues; /* Wait queue pointer */
Ian Kentf50b6f82007-02-20 13:58:10 -0800115 spinlock_t rehash_lock;
116 struct list_head rehash_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117};
118
119static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb)
120{
121 return (struct autofs_sb_info *)(sb->s_fs_info);
122}
123
124static 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
133static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) {
Pavel Emelianova47afb02007-10-18 23:39:46 -0700134 return sbi->catatonic || task_pgrp_nr(current) == sbi->oz_pgrp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135}
136
137/* Does a dentry have some pending activity? */
138static inline int autofs4_ispending(struct dentry *dentry)
139{
140 struct autofs_info *inf = autofs4_dentry_ino(dentry);
Ian Kent3a9720c2005-05-01 08:59:17 -0700141 int pending = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142
Ian Kent3a9720c2005-05-01 08:59:17 -0700143 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;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153}
154
155static inline void autofs4_copy_atime(struct file *src, struct file *dst)
156{
Josef "Jeff" Sipeka4669ed2006-12-08 02:36:46 -0800157 dst->f_path.dentry->d_inode->i_atime =
158 src->f_path.dentry->d_inode->i_atime;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159 return;
160}
161
162struct inode *autofs4_get_inode(struct super_block *, struct autofs_info *);
163void autofs4_free_ino(struct autofs_info *);
164
165/* Expiration */
166int is_autofs4_dentry(struct dentry *);
167int autofs4_expire_run(struct super_block *, struct vfsmount *,
168 struct autofs_sb_info *,
169 struct autofs_packet_expire __user *);
170int autofs4_expire_multi(struct super_block *, struct vfsmount *,
171 struct autofs_sb_info *, int __user *);
172
173/* Operations structures */
174
Arjan van de Ven754661f2007-02-12 00:55:38 -0800175extern const struct inode_operations autofs4_symlink_inode_operations;
176extern const struct inode_operations autofs4_dir_inode_operations;
177extern const struct inode_operations autofs4_root_inode_operations;
178extern const struct inode_operations autofs4_indirect_root_inode_operations;
179extern const struct inode_operations autofs4_direct_root_inode_operations;
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -0800180extern const struct file_operations autofs4_dir_operations;
181extern const struct file_operations autofs4_root_operations;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182
183/* Initializing function */
184
185int autofs4_fill_super(struct super_block *, void *, int);
186struct autofs_info *autofs4_init_ino(struct autofs_info *, struct autofs_sb_info *sbi, mode_t mode);
187
188/* Queue management functions */
189
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190int autofs4_wait(struct autofs_sb_info *,struct dentry *, enum autofs_notify);
191int autofs4_wait_release(struct autofs_sb_info *,autofs_wqt_t,int);
192void autofs4_catatonic_mode(struct autofs_sb_info *);
193
Ian Kent9b1e3af2005-06-21 17:16:38 -0700194static 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
Ian Kent5c0a32f2006-03-27 01:14:55 -0800207static inline u32 autofs4_get_dev(struct autofs_sb_info *sbi)
208{
209 return new_encode_dev(sbi->sb->s_dev);
210}
211
212static inline u64 autofs4_get_ino(struct autofs_sb_info *sbi)
213{
214 return sbi->sb->s_root->d_inode->i_ino;
215}
216
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217static inline int simple_positive(struct dentry *dentry)
218{
219 return dentry->d_inode && !d_unhashed(dentry);
220}
221
Ian Kent90a59c72006-03-27 01:14:50 -0800222static inline int __simple_empty(struct dentry *dentry)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223{
224 struct dentry *child;
225 int ret = 0;
226
Eric Dumazet5160ee62006-01-08 01:03:32 -0800227 list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700228 if (simple_positive(child))
229 goto out;
230 ret = 1;
231out:
232 return ret;
233}
Adrian Bunkf5b95ff2006-03-28 01:56:29 -0800234
235void autofs4_dentry_release(struct dentry *);
David Howells6ce31522006-10-11 01:22:15 -0700236extern void autofs4_kill_sb(struct super_block *);