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 | |
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> | |
1d5599e3 | 16 | #include <linux/mutex.h> |
1da177e4 LT |
17 | #include <linux/list.h> |
18 | ||
19 | /* This is the range of ioctl() numbers we claim as ours */ | |
20 | #define AUTOFS_IOC_FIRST AUTOFS_IOC_READY | |
21 | #define AUTOFS_IOC_COUNT 32 | |
22 | ||
23 | #include <linux/kernel.h> | |
24 | #include <linux/slab.h> | |
25 | #include <linux/time.h> | |
26 | #include <linux/string.h> | |
27 | #include <linux/wait.h> | |
28 | #include <linux/sched.h> | |
29 | #include <linux/mount.h> | |
30 | #include <linux/namei.h> | |
31 | #include <asm/current.h> | |
32 | #include <asm/uaccess.h> | |
33 | ||
34 | /* #define DEBUG */ | |
35 | ||
36 | #ifdef DEBUG | |
37 | #define DPRINTK(fmt,args...) do { printk(KERN_DEBUG "pid %d: %s: " fmt "\n" , current->pid , __FUNCTION__ , ##args); } while(0) | |
38 | #else | |
39 | #define DPRINTK(fmt,args...) do {} while(0) | |
40 | #endif | |
41 | ||
42 | #define AUTOFS_SUPER_MAGIC 0x0187 | |
43 | ||
1da177e4 LT |
44 | /* Unified info structure. This is pointed to by both the dentry and |
45 | inode structures. Each file in the filesystem has an instance of this | |
46 | structure. It holds a reference to the dentry, so dentries are never | |
47 | flushed while the file exists. All name lookups are dealt with at the | |
48 | dentry level, although the filesystem can interfere in the validation | |
49 | process. Readdir is implemented by traversing the dentry lists. */ | |
50 | struct autofs_info { | |
51 | struct dentry *dentry; | |
52 | struct inode *inode; | |
53 | ||
54 | int flags; | |
55 | ||
56 | struct autofs_sb_info *sbi; | |
57 | unsigned long last_used; | |
58 | ||
59 | mode_t mode; | |
60 | size_t size; | |
61 | ||
62 | void (*free)(struct autofs_info *); | |
63 | union { | |
64 | const char *symlink; | |
65 | } u; | |
66 | }; | |
67 | ||
68 | #define AUTOFS_INF_EXPIRING (1<<0) /* dentry is in the process of expiring */ | |
69 | ||
70 | struct autofs_wait_queue { | |
71 | wait_queue_head_t queue; | |
72 | struct autofs_wait_queue *next; | |
73 | autofs_wqt_t wait_queue_token; | |
74 | /* We use the following to see what we are waiting for */ | |
75 | int hash; | |
76 | int len; | |
77 | char *name; | |
78 | /* This is for status reporting upon return */ | |
79 | int status; | |
4dcd00b1 | 80 | atomic_t notified; |
1da177e4 LT |
81 | atomic_t wait_ctr; |
82 | }; | |
83 | ||
84 | #define AUTOFS_SBI_MAGIC 0x6d4a556d | |
85 | ||
86 | struct autofs_sb_info { | |
87 | u32 magic; | |
104e49fc | 88 | struct dentry *root; |
1da177e4 LT |
89 | struct file *pipe; |
90 | pid_t oz_pgrp; | |
91 | int catatonic; | |
92 | int version; | |
93 | int sub_version; | |
94 | unsigned long exp_timeout; | |
95 | int reghost_enabled; | |
96 | int needs_reghost; | |
97 | struct super_block *sb; | |
1d5599e3 | 98 | struct mutex wq_mutex; |
3a9720ce | 99 | spinlock_t fs_lock; |
1da177e4 LT |
100 | struct autofs_wait_queue *queues; /* Wait queue pointer */ |
101 | }; | |
102 | ||
103 | static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb) | |
104 | { | |
105 | return (struct autofs_sb_info *)(sb->s_fs_info); | |
106 | } | |
107 | ||
108 | static inline struct autofs_info *autofs4_dentry_ino(struct dentry *dentry) | |
109 | { | |
110 | return (struct autofs_info *)(dentry->d_fsdata); | |
111 | } | |
112 | ||
113 | /* autofs4_oz_mode(): do we see the man behind the curtain? (The | |
114 | processes which do manipulations for us in user space sees the raw | |
115 | filesystem without "magic".) */ | |
116 | ||
117 | static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) { | |
118 | return sbi->catatonic || process_group(current) == sbi->oz_pgrp; | |
119 | } | |
120 | ||
121 | /* Does a dentry have some pending activity? */ | |
122 | static inline int autofs4_ispending(struct dentry *dentry) | |
123 | { | |
124 | struct autofs_info *inf = autofs4_dentry_ino(dentry); | |
3a9720ce | 125 | int pending = 0; |
1da177e4 | 126 | |
3a9720ce IK |
127 | if (dentry->d_flags & DCACHE_AUTOFS_PENDING) |
128 | return 1; | |
129 | ||
130 | if (inf) { | |
131 | spin_lock(&inf->sbi->fs_lock); | |
132 | pending = inf->flags & AUTOFS_INF_EXPIRING; | |
133 | spin_unlock(&inf->sbi->fs_lock); | |
134 | } | |
135 | ||
136 | return pending; | |
1da177e4 LT |
137 | } |
138 | ||
139 | static inline void autofs4_copy_atime(struct file *src, struct file *dst) | |
140 | { | |
141 | dst->f_dentry->d_inode->i_atime = src->f_dentry->d_inode->i_atime; | |
142 | return; | |
143 | } | |
144 | ||
145 | struct inode *autofs4_get_inode(struct super_block *, struct autofs_info *); | |
146 | void autofs4_free_ino(struct autofs_info *); | |
147 | ||
148 | /* Expiration */ | |
149 | int is_autofs4_dentry(struct dentry *); | |
150 | int autofs4_expire_run(struct super_block *, struct vfsmount *, | |
151 | struct autofs_sb_info *, | |
152 | struct autofs_packet_expire __user *); | |
153 | int autofs4_expire_multi(struct super_block *, struct vfsmount *, | |
154 | struct autofs_sb_info *, int __user *); | |
155 | ||
156 | /* Operations structures */ | |
157 | ||
158 | extern struct inode_operations autofs4_symlink_inode_operations; | |
159 | extern struct inode_operations autofs4_dir_inode_operations; | |
160 | extern struct inode_operations autofs4_root_inode_operations; | |
161 | extern struct file_operations autofs4_dir_operations; | |
162 | extern struct file_operations autofs4_root_operations; | |
163 | ||
164 | /* Initializing function */ | |
165 | ||
166 | int autofs4_fill_super(struct super_block *, void *, int); | |
167 | struct autofs_info *autofs4_init_ino(struct autofs_info *, struct autofs_sb_info *sbi, mode_t mode); | |
168 | ||
169 | /* Queue management functions */ | |
170 | ||
171 | enum autofs_notify | |
172 | { | |
173 | NFY_NONE, | |
174 | NFY_MOUNT, | |
175 | NFY_EXPIRE | |
176 | }; | |
177 | ||
178 | int autofs4_wait(struct autofs_sb_info *,struct dentry *, enum autofs_notify); | |
179 | int autofs4_wait_release(struct autofs_sb_info *,autofs_wqt_t,int); | |
180 | void autofs4_catatonic_mode(struct autofs_sb_info *); | |
181 | ||
9b1e3afd IK |
182 | static inline int autofs4_follow_mount(struct vfsmount **mnt, struct dentry **dentry) |
183 | { | |
184 | int res = 0; | |
185 | ||
186 | while (d_mountpoint(*dentry)) { | |
187 | int followed = follow_down(mnt, dentry); | |
188 | if (!followed) | |
189 | break; | |
190 | res = 1; | |
191 | } | |
192 | return res; | |
193 | } | |
194 | ||
1da177e4 LT |
195 | static inline int simple_positive(struct dentry *dentry) |
196 | { | |
197 | return dentry->d_inode && !d_unhashed(dentry); | |
198 | } | |
199 | ||
200 | static inline int simple_empty_nolock(struct dentry *dentry) | |
201 | { | |
202 | struct dentry *child; | |
203 | int ret = 0; | |
204 | ||
5160ee6f | 205 | list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child) |
1da177e4 LT |
206 | if (simple_positive(child)) |
207 | goto out; | |
208 | ret = 1; | |
209 | out: | |
210 | return ret; | |
211 | } |