2 * Copyright 1997-1998 Transmeta Corporation - All Rights Reserved
3 * Copyright 2005-2006 Ian Kent <raven@themaw.net>
5 * This file is part of the Linux kernel and is made available under
6 * the terms of the GNU General Public License, version 2, or at your
7 * option, any later version, incorporated herein by reference.
10 /* Internal header file for autofs */
12 #include <linux/auto_fs4.h>
13 #include <linux/auto_dev-ioctl.h>
14 #include <linux/mutex.h>
15 #include <linux/spinlock.h>
16 #include <linux/list.h>
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
22 #define AUTOFS_DEV_IOCTL_IOC_FIRST (AUTOFS_DEV_IOCTL_VERSION)
23 #define AUTOFS_DEV_IOCTL_IOC_COUNT (AUTOFS_IOC_COUNT - 11)
25 #include <linux/kernel.h>
26 #include <linux/slab.h>
27 #include <linux/time.h>
28 #include <linux/string.h>
29 #include <linux/wait.h>
30 #include <linux/sched.h>
31 #include <linux/mount.h>
32 #include <linux/namei.h>
33 #include <asm/current.h>
34 #include <linux/uaccess.h>
38 #define DPRINTK(fmt, ...) \
39 pr_debug(KBUILD_MODNAME ":pid:%d:%s: " fmt, \
40 current->pid, __func__, ##__VA_ARGS__)
42 #define AUTOFS_WARN(fmt, ...) \
43 pr_warn(KBUILD_MODNAME ":pid:%d:%s: " fmt, \
44 current->pid, __func__, ##__VA_ARGS__)
46 #define AUTOFS_ERROR(fmt, ...) \
47 pr_err(KBUILD_MODNAME ":pid:%d:%s: " fmt, \
48 current->pid, __func__, ##__VA_ARGS__)
51 * Unified info structure. This is pointed to by both the dentry and
52 * inode structures. Each file in the filesystem has an instance of this
53 * structure. It holds a reference to the dentry, so dentries are never
54 * flushed while the file exists. All name lookups are dealt with at the
55 * dentry level, although the filesystem can interfere in the validation
56 * process. Readdir is implemented by traversing the dentry lists.
59 struct dentry *dentry;
64 struct completion expire_complete;
66 struct list_head active;
69 struct list_head expiring;
71 struct autofs_sb_info *sbi;
72 unsigned long last_used;
79 #define AUTOFS_INF_EXPIRING (1<<0) /* dentry in the process of expiring */
80 #define AUTOFS_INF_NO_RCU (1<<1) /* the dentry is being considered
81 * for expiry, so RCU_walk is
84 #define AUTOFS_INF_PENDING (1<<2) /* dentry pending mount */
86 struct autofs_wait_queue {
87 wait_queue_head_t queue;
88 struct autofs_wait_queue *next;
89 autofs_wqt_t wait_queue_token;
90 /* We use the following to see what we are waiting for */
98 /* This is for status reporting upon return */
100 unsigned int wait_ctr;
103 #define AUTOFS_SBI_MAGIC 0x6d4a556d
105 struct autofs_sb_info {
115 unsigned long exp_timeout;
119 struct super_block *sb;
120 struct mutex wq_mutex;
121 struct mutex pipe_mutex;
123 struct autofs_wait_queue *queues; /* Wait queue pointer */
124 spinlock_t lookup_lock;
125 struct list_head active_list;
126 struct list_head expiring_list;
130 static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb)
132 return (struct autofs_sb_info *)(sb->s_fs_info);
135 static inline struct autofs_info *autofs4_dentry_ino(struct dentry *dentry)
137 return (struct autofs_info *)(dentry->d_fsdata);
140 /* autofs4_oz_mode(): do we see the man behind the curtain? (The
141 * processes which do manipulations for us in user space sees the raw
142 * filesystem without "magic".)
144 static inline int autofs4_oz_mode(struct autofs_sb_info *sbi)
146 return sbi->catatonic || task_pgrp(current) == sbi->oz_pgrp;
149 struct inode *autofs4_get_inode(struct super_block *, umode_t);
150 void autofs4_free_ino(struct autofs_info *);
153 int is_autofs4_dentry(struct dentry *);
154 int autofs4_expire_wait(struct dentry *dentry, int rcu_walk);
155 int autofs4_expire_run(struct super_block *, struct vfsmount *,
156 struct autofs_sb_info *,
157 struct autofs_packet_expire __user *);
158 int autofs4_do_expire_multi(struct super_block *sb, struct vfsmount *mnt,
159 struct autofs_sb_info *sbi, int when);
160 int autofs4_expire_multi(struct super_block *, struct vfsmount *,
161 struct autofs_sb_info *, int __user *);
162 struct dentry *autofs4_expire_direct(struct super_block *sb,
163 struct vfsmount *mnt,
164 struct autofs_sb_info *sbi, int how);
165 struct dentry *autofs4_expire_indirect(struct super_block *sb,
166 struct vfsmount *mnt,
167 struct autofs_sb_info *sbi, int how);
169 /* Device node initialization */
171 int autofs_dev_ioctl_init(void);
172 void autofs_dev_ioctl_exit(void);
174 /* Operations structures */
176 extern const struct inode_operations autofs4_symlink_inode_operations;
177 extern const struct inode_operations autofs4_dir_inode_operations;
178 extern const struct file_operations autofs4_dir_operations;
179 extern const struct file_operations autofs4_root_operations;
180 extern const struct dentry_operations autofs4_dentry_operations;
182 /* VFS automount flags management functions */
183 static inline void __managed_dentry_set_managed(struct dentry *dentry)
185 dentry->d_flags |= (DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT);
188 static inline void managed_dentry_set_managed(struct dentry *dentry)
190 spin_lock(&dentry->d_lock);
191 __managed_dentry_set_managed(dentry);
192 spin_unlock(&dentry->d_lock);
195 static inline void __managed_dentry_clear_managed(struct dentry *dentry)
197 dentry->d_flags &= ~(DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT);
200 static inline void managed_dentry_clear_managed(struct dentry *dentry)
202 spin_lock(&dentry->d_lock);
203 __managed_dentry_clear_managed(dentry);
204 spin_unlock(&dentry->d_lock);
207 /* Initializing function */
209 int autofs4_fill_super(struct super_block *, void *, int);
210 struct autofs_info *autofs4_new_ino(struct autofs_sb_info *);
211 void autofs4_clean_ino(struct autofs_info *);
213 static inline int autofs_prepare_pipe(struct file *pipe)
215 if (!(pipe->f_mode & FMODE_CAN_WRITE))
217 if (!S_ISFIFO(file_inode(pipe)->i_mode))
219 /* We want a packet pipe */
220 pipe->f_flags |= O_DIRECT;
224 /* Queue management functions */
226 int autofs4_wait(struct autofs_sb_info *, struct dentry *, enum autofs_notify);
227 int autofs4_wait_release(struct autofs_sb_info *, autofs_wqt_t, int);
228 void autofs4_catatonic_mode(struct autofs_sb_info *);
230 static inline u32 autofs4_get_dev(struct autofs_sb_info *sbi)
232 return new_encode_dev(sbi->sb->s_dev);
235 static inline u64 autofs4_get_ino(struct autofs_sb_info *sbi)
237 return d_inode(sbi->sb->s_root)->i_ino;
240 static inline void __autofs4_add_expiring(struct dentry *dentry)
242 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
243 struct autofs_info *ino = autofs4_dentry_ino(dentry);
246 if (list_empty(&ino->expiring))
247 list_add(&ino->expiring, &sbi->expiring_list);
251 static inline void autofs4_add_expiring(struct dentry *dentry)
253 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
254 struct autofs_info *ino = autofs4_dentry_ino(dentry);
257 spin_lock(&sbi->lookup_lock);
258 if (list_empty(&ino->expiring))
259 list_add(&ino->expiring, &sbi->expiring_list);
260 spin_unlock(&sbi->lookup_lock);
264 static inline void autofs4_del_expiring(struct dentry *dentry)
266 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
267 struct autofs_info *ino = autofs4_dentry_ino(dentry);
270 spin_lock(&sbi->lookup_lock);
271 if (!list_empty(&ino->expiring))
272 list_del_init(&ino->expiring);
273 spin_unlock(&sbi->lookup_lock);
277 extern void autofs4_kill_sb(struct super_block *);