Commit | Line | Data |
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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; | |
80 | /* This is for status reporting upon return */ | |
81 | int status; | |
4dcd00b1 | 82 | atomic_t notified; |
1da177e4 LT |
83 | atomic_t wait_ctr; |
84 | }; | |
85 | ||
86 | #define AUTOFS_SBI_MAGIC 0x6d4a556d | |
87 | ||
34ca959c IK |
88 | #define AUTOFS_TYP_INDIRECT 0x0001 |
89 | #define AUTOFS_TYP_DIRECT 0x0002 | |
90 | #define AUTOFS_TYP_OFFSET 0x0004 | |
91 | ||
1da177e4 LT |
92 | struct autofs_sb_info { |
93 | u32 magic; | |
104e49fc | 94 | struct dentry *root; |
d7c4a5f1 | 95 | int pipefd; |
1da177e4 LT |
96 | struct file *pipe; |
97 | pid_t oz_pgrp; | |
98 | int catatonic; | |
99 | int version; | |
100 | int sub_version; | |
d7c4a5f1 IK |
101 | int min_proto; |
102 | int max_proto; | |
1da177e4 | 103 | unsigned long exp_timeout; |
34ca959c | 104 | unsigned int type; |
1da177e4 LT |
105 | int reghost_enabled; |
106 | int needs_reghost; | |
107 | struct super_block *sb; | |
1d5599e3 | 108 | struct mutex wq_mutex; |
3a9720ce | 109 | spinlock_t fs_lock; |
1da177e4 LT |
110 | struct autofs_wait_queue *queues; /* Wait queue pointer */ |
111 | }; | |
112 | ||
113 | static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb) | |
114 | { | |
115 | return (struct autofs_sb_info *)(sb->s_fs_info); | |
116 | } | |
117 | ||
118 | static inline struct autofs_info *autofs4_dentry_ino(struct dentry *dentry) | |
119 | { | |
120 | return (struct autofs_info *)(dentry->d_fsdata); | |
121 | } | |
122 | ||
123 | /* autofs4_oz_mode(): do we see the man behind the curtain? (The | |
124 | processes which do manipulations for us in user space sees the raw | |
125 | filesystem without "magic".) */ | |
126 | ||
127 | static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) { | |
128 | return sbi->catatonic || process_group(current) == sbi->oz_pgrp; | |
129 | } | |
130 | ||
131 | /* Does a dentry have some pending activity? */ | |
132 | static inline int autofs4_ispending(struct dentry *dentry) | |
133 | { | |
134 | struct autofs_info *inf = autofs4_dentry_ino(dentry); | |
3a9720ce | 135 | int pending = 0; |
1da177e4 | 136 | |
3a9720ce IK |
137 | if (dentry->d_flags & DCACHE_AUTOFS_PENDING) |
138 | return 1; | |
139 | ||
140 | if (inf) { | |
141 | spin_lock(&inf->sbi->fs_lock); | |
142 | pending = inf->flags & AUTOFS_INF_EXPIRING; | |
143 | spin_unlock(&inf->sbi->fs_lock); | |
144 | } | |
145 | ||
146 | return pending; | |
1da177e4 LT |
147 | } |
148 | ||
149 | static inline void autofs4_copy_atime(struct file *src, struct file *dst) | |
150 | { | |
151 | dst->f_dentry->d_inode->i_atime = src->f_dentry->d_inode->i_atime; | |
152 | return; | |
153 | } | |
154 | ||
155 | struct inode *autofs4_get_inode(struct super_block *, struct autofs_info *); | |
156 | void autofs4_free_ino(struct autofs_info *); | |
157 | ||
158 | /* Expiration */ | |
159 | int is_autofs4_dentry(struct dentry *); | |
160 | int autofs4_expire_run(struct super_block *, struct vfsmount *, | |
161 | struct autofs_sb_info *, | |
162 | struct autofs_packet_expire __user *); | |
163 | int autofs4_expire_multi(struct super_block *, struct vfsmount *, | |
164 | struct autofs_sb_info *, int __user *); | |
165 | ||
166 | /* Operations structures */ | |
167 | ||
168 | extern struct inode_operations autofs4_symlink_inode_operations; | |
169 | extern struct inode_operations autofs4_dir_inode_operations; | |
170 | extern struct inode_operations autofs4_root_inode_operations; | |
34ca959c IK |
171 | extern struct inode_operations autofs4_indirect_root_inode_operations; |
172 | extern struct inode_operations autofs4_direct_root_inode_operations; | |
1da177e4 LT |
173 | extern struct file_operations autofs4_dir_operations; |
174 | extern struct file_operations autofs4_root_operations; | |
175 | ||
176 | /* Initializing function */ | |
177 | ||
178 | int autofs4_fill_super(struct super_block *, void *, int); | |
179 | struct autofs_info *autofs4_init_ino(struct autofs_info *, struct autofs_sb_info *sbi, mode_t mode); | |
180 | ||
181 | /* Queue management functions */ | |
182 | ||
183 | enum autofs_notify | |
184 | { | |
185 | NFY_NONE, | |
186 | NFY_MOUNT, | |
187 | NFY_EXPIRE | |
188 | }; | |
189 | ||
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 | ||
1da177e4 LT |
207 | static inline int simple_positive(struct dentry *dentry) |
208 | { | |
209 | return dentry->d_inode && !d_unhashed(dentry); | |
210 | } | |
211 | ||
90a59c7c | 212 | static inline int __simple_empty(struct dentry *dentry) |
1da177e4 LT |
213 | { |
214 | struct dentry *child; | |
215 | int ret = 0; | |
216 | ||
5160ee6f | 217 | list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child) |
1da177e4 LT |
218 | if (simple_positive(child)) |
219 | goto out; | |
220 | ret = 1; | |
221 | out: | |
222 | return ret; | |
223 | } |