1 /* -*- c -*- ------------------------------------------------------------- *
2 *
3 * linux/fs/autofs/autofs_i.h
4 *
5 * Copyright 1997-1998 Transmeta Corporation - All Rights Reserved
6 *
7 * This file is part of the Linux kernel and is made available under
8 * the terms of the GNU General Public License, version 2, or at your
9 * option, any later version, incorporated herein by reference.
10 *
11 * ----------------------------------------------------------------------- */
12
13 /* Internal header file for autofs */
14
15 #include <linux/auto_fs4.h>
16 #include <linux/list.h>
17
18 /* This is the range of ioctl() numbers we claim as ours */
19 #define AUTOFS_IOC_FIRST AUTOFS_IOC_READY
20 #define AUTOFS_IOC_COUNT 32
21
22 #include <linux/kernel.h>
23 #include <linux/slab.h>
24 #include <linux/sched.h>
25 #include <linux/string.h>
26 #include <linux/wait.h>
27 #include <asm/uaccess.h>
28
29 /* #define DEBUG */
30
31 #ifdef DEBUG
32 #define DPRINTK(D) do{ printk("pid %d: ", current->pid); printk D; } while(0)
33 #else
34 #define DPRINTK(D) do {} while(0)
35 #endif
36
37 #define AUTOFS_SUPER_MAGIC 0x0187
38
39 /*
40 * If the daemon returns a negative response (AUTOFS_IOC_FAIL) then the
41 * kernel will keep the negative response cached for up to the time given
42 * here, although the time can be shorter if the kernel throws the dcache
43 * entry away. This probably should be settable from user space.
44 */
45 #define AUTOFS_NEGATIVE_TIMEOUT (60*HZ) /* 1 minute */
46
47 /* Unified info structure. This is pointed to by both the dentry and
48 inode structures. Each file in the filesystem has an instance of this
49 structure. It holds a reference to the dentry, so dentries are never
50 flushed while the file exists. All name lookups are dealt with at the
51 dentry level, although the filesystem can interfere in the validation
52 process. Readdir is implemented by traversing the dentry lists. */
53 struct autofs_info {
54 struct dentry *dentry;
55 struct inode *inode;
56
57 int flags;
58
59 struct autofs_sb_info *sbi;
60 unsigned long last_used;
61
62 mode_t mode;
63 size_t size;
64
65 void (*free)(struct autofs_info *);
66 union {
67 const char *symlink;
68 } u;
69 };
70
71 #define AUTOFS_INF_EXPIRING (1<<0) /* dentry is in the process of expiring */
72
73 struct autofs_wait_queue {
74 wait_queue_head_t queue;
75 struct autofs_wait_queue *next;
76 autofs_wqt_t wait_queue_token;
77 /* We use the following to see what we are waiting for */
78 int hash;
79 int len;
80 char *name;
81 /* This is for status reporting upon return */
82 int status;
83 int wait_ctr;
84 };
85
86 #define AUTOFS_SBI_MAGIC 0x6d4a556d
87
88 struct autofs_sb_info {
89 u32 magic;
90 struct file *pipe;
91 pid_t oz_pgrp;
92 int catatonic;
93 int version;
94 unsigned long exp_timeout;
95 struct super_block *sb;
96 struct autofs_wait_queue *queues; /* Wait queue pointer */
97 };
98
autofs4_sbi(struct super_block * sb)99 static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb)
100 {
101 return (struct autofs_sb_info *)(sb->u.generic_sbp);
102 }
103
autofs4_dentry_ino(struct dentry * dentry)104 static inline struct autofs_info *autofs4_dentry_ino(struct dentry *dentry)
105 {
106 return (struct autofs_info *)(dentry->d_fsdata);
107 }
108
109 /* autofs4_oz_mode(): do we see the man behind the curtain? (The
110 processes which do manipulations for us in user space sees the raw
111 filesystem without "magic".) */
112
autofs4_oz_mode(struct autofs_sb_info * sbi)113 static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) {
114 return sbi->catatonic || current->pgrp == sbi->oz_pgrp;
115 }
116
117 /* Does a dentry have some pending activity? */
autofs4_ispending(struct dentry * dentry)118 static inline int autofs4_ispending(struct dentry *dentry)
119 {
120 struct autofs_info *inf = autofs4_dentry_ino(dentry);
121
122 return (dentry->d_flags & DCACHE_AUTOFS_PENDING) ||
123 (inf != NULL && inf->flags & AUTOFS_INF_EXPIRING);
124 }
125
126 struct inode *autofs4_get_inode(struct super_block *, struct autofs_info *);
127 struct autofs_info *autofs4_init_inf(struct autofs_sb_info *, mode_t mode);
128 void autofs4_free_ino(struct autofs_info *);
129
130 /* Expiration */
131 int is_autofs4_dentry(struct dentry *);
132 int autofs4_expire_run(struct super_block *, struct vfsmount *,
133 struct autofs_sb_info *, struct autofs_packet_expire *);
134 int autofs4_expire_multi(struct super_block *, struct vfsmount *,
135 struct autofs_sb_info *, int *);
136
137 /* Operations structures */
138
139 extern struct inode_operations autofs4_symlink_inode_operations;
140 extern struct inode_operations autofs4_dir_inode_operations;
141 extern struct inode_operations autofs4_root_inode_operations;
142 extern struct file_operations autofs4_root_operations;
143
144 /* Initializing function */
145
146 struct super_block *autofs4_read_super(struct super_block *, void *,int);
147 struct autofs_info *autofs4_init_ino(struct autofs_info *, struct autofs_sb_info *sbi, mode_t mode);
148
149 /* Queue management functions */
150
151 enum autofs_notify
152 {
153 NFY_NONE,
154 NFY_MOUNT,
155 NFY_EXPIRE
156 };
157
158 int autofs4_wait(struct autofs_sb_info *,struct qstr *, enum autofs_notify);
159 int autofs4_wait_release(struct autofs_sb_info *,autofs_wqt_t,int);
160 void autofs4_catatonic_mode(struct autofs_sb_info *);
161