1 /* -*- c -*- ------------------------------------------------------------- *
2 *
3 * linux/fs/autofs/autofs_i.h
4 *
5 * Copyright 1997-1998 Transmeta Corporation - All Rights Reserved
6 * Copyright 2005-2006 Ian Kent <raven@themaw.net>
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>
17 #include <linux/mutex.h>
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 /* 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. */
49 struct autofs_info {
50 struct dentry *dentry;
51 struct inode *inode;
52
53 int flags;
54
55 struct list_head rehash;
56
57 struct autofs_sb_info *sbi;
58 unsigned long last_used;
59 atomic_t count;
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 unsigned int hash;
78 unsigned int len;
79 char *name;
80 u32 dev;
81 u64 ino;
82 uid_t uid;
83 gid_t gid;
84 pid_t pid;
85 pid_t tgid;
86 /* This is for status reporting upon return */
87 int status;
88 atomic_t wait_ctr;
89 };
90
91 #define AUTOFS_SBI_MAGIC 0x6d4a556d
92
93 #define AUTOFS_TYPE_INDIRECT 0x0001
94 #define AUTOFS_TYPE_DIRECT 0x0002
95 #define AUTOFS_TYPE_OFFSET 0x0004
96
97 struct autofs_sb_info {
98 u32 magic;
99 int pipefd;
100 struct file *pipe;
101 pid_t oz_pgrp;
102 int catatonic;
103 int version;
104 int sub_version;
105 int min_proto;
106 int max_proto;
107 unsigned long exp_timeout;
108 unsigned int type;
109 int reghost_enabled;
110 int needs_reghost;
111 struct super_block *sb;
112 struct mutex wq_mutex;
113 spinlock_t fs_lock;
114 struct autofs_wait_queue *queues; /* Wait queue pointer */
115 spinlock_t rehash_lock;
116 struct list_head rehash_list;
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 || task_pgrp_nr(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);
141 int pending = 0;
142
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;
153 }
154
155 static inline void autofs4_copy_atime(struct file *src, struct file *dst)
156 {
157 dst->f_path.dentry->d_inode->i_atime =
158 src->f_path.dentry->d_inode->i_atime;
159 return;
160 }
161
162 struct inode *autofs4_get_inode(struct super_block *, struct autofs_info *);
163 void autofs4_free_ino(struct autofs_info *);
164
165 /* Expiration */
166 int is_autofs4_dentry(struct dentry *);
167 int autofs4_expire_run(struct super_block *, struct vfsmount *,
168 struct autofs_sb_info *,
169 struct autofs_packet_expire __user *);
170 int autofs4_expire_multi(struct super_block *, struct vfsmount *,
171 struct autofs_sb_info *, int __user *);
172
173 /* Operations structures */
174
175 extern const struct inode_operations autofs4_symlink_inode_operations;
176 extern const struct inode_operations autofs4_dir_inode_operations;
177 extern const struct inode_operations autofs4_root_inode_operations;
178 extern const struct inode_operations autofs4_indirect_root_inode_operations;
179 extern const struct inode_operations autofs4_direct_root_inode_operations;
180 extern const struct file_operations autofs4_dir_operations;
181 extern const struct file_operations autofs4_root_operations;
182
183 /* Initializing function */
184
185 int autofs4_fill_super(struct super_block *, void *, int);
186 struct autofs_info *autofs4_init_ino(struct autofs_info *, struct autofs_sb_info *sbi, mode_t mode);
187
188 /* Queue management functions */
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
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
207 static inline u32 autofs4_get_dev(struct autofs_sb_info *sbi)
208 {
209 return new_encode_dev(sbi->sb->s_dev);
210 }
211
212 static inline u64 autofs4_get_ino(struct autofs_sb_info *sbi)
213 {
214 return sbi->sb->s_root->d_inode->i_ino;
215 }
216
217 static inline int simple_positive(struct dentry *dentry)
218 {
219 return dentry->d_inode && !d_unhashed(dentry);
220 }
221
222 static inline int __simple_empty(struct dentry *dentry)
223 {
224 struct dentry *child;
225 int ret = 0;
226
227 list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child)
228 if (simple_positive(child))
229 goto out;
230 ret = 1;
231 out:
232 return ret;
233 }
234
235 void autofs4_dentry_release(struct dentry *);
236 extern void autofs4_kill_sb(struct super_block *);
237
|
This page was automatically generated by the
LXR engine.
|