1 /* -*- c -*- ------------------------------------------------------------- *
3 * linux/fs/autofs/autofs_i.h
5 * Copyright 1997-1998 Transmeta Corporation - All Rights Reserved
6 * Copyright 2005-2006 Ian Kent <raven@themaw.net>
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.
12 * ----------------------------------------------------------------------- */
14 /* Internal header file for autofs */
16 #include <linux/auto_fs4.h>
17 #include <linux/auto_dev-ioctl.h>
18 #include <linux/mutex.h>
19 #include <linux/spinlock.h>
20 #include <linux/list.h>
22 /* This is the range of ioctl() numbers we claim as ours */
23 #define AUTOFS_IOC_FIRST AUTOFS_IOC_READY
24 #define AUTOFS_IOC_COUNT 32
26 #define AUTOFS_DEV_IOCTL_IOC_FIRST (AUTOFS_DEV_IOCTL_VERSION)
27 #define AUTOFS_DEV_IOCTL_IOC_COUNT (AUTOFS_IOC_COUNT - 11)
29 #include <linux/kernel.h>
30 #include <linux/slab.h>
31 #include <linux/time.h>
32 #include <linux/string.h>
33 #include <linux/wait.h>
34 #include <linux/sched.h>
35 #include <linux/mount.h>
36 #include <linux/namei.h>
37 #include <linux/delay.h>
38 #include <asm/current.h>
39 #include <asm/uaccess.h>
43 #define DPRINTK(fmt, ...) \
44 pr_debug("pid %d: %s: " fmt "\n", \
45 current->pid, __func__, ##__VA_ARGS__)
47 #define AUTOFS_WARN(fmt, ...) \
48 printk(KERN_WARNING "pid %d: %s: " fmt "\n", \
49 current->pid, __func__, ##__VA_ARGS__)
51 #define AUTOFS_ERROR(fmt, ...) \
52 printk(KERN_ERR "pid %d: %s: " fmt "\n", \
53 current->pid, __func__, ##__VA_ARGS__)
55 /* Unified info structure. This is pointed to by both the dentry and
56 inode structures. Each file in the filesystem has an instance of this
57 structure. It holds a reference to the dentry, so dentries are never
58 flushed while the file exists. All name lookups are dealt with at the
59 dentry level, although the filesystem can interfere in the validation
60 process. Readdir is implemented by traversing the dentry lists. */
62 struct dentry *dentry;
67 struct completion expire_complete;
69 struct list_head active;
72 struct list_head expiring;
74 struct autofs_sb_info *sbi;
75 unsigned long last_used;
82 #define AUTOFS_INF_EXPIRING (1<<0) /* dentry is in the process of expiring */
83 #define AUTOFS_INF_WANT_EXPIRE (1<<1) /* the dentry is being considered
84 * for expiry, so RCU_walk is
85 * not permitted. If it progresses to
86 * actual expiry attempt, the flag is
87 * not cleared when EXPIRING is set -
88 * in that case it gets cleared only
89 * when it comes to clearing EXPIRING.
91 #define AUTOFS_INF_PENDING (1<<2) /* dentry pending mount */
93 struct autofs_wait_queue {
94 wait_queue_head_t queue;
95 struct autofs_wait_queue *next;
96 autofs_wqt_t wait_queue_token;
97 /* We use the following to see what we are waiting for */
105 /* This is for status reporting upon return */
107 unsigned int wait_ctr;
110 #define AUTOFS_SBI_MAGIC 0x6d4a556d
112 struct autofs_sb_info {
122 unsigned long exp_timeout;
126 struct super_block *sb;
127 struct mutex wq_mutex;
128 struct mutex pipe_mutex;
130 struct autofs_wait_queue *queues; /* Wait queue pointer */
131 spinlock_t lookup_lock;
132 struct list_head active_list;
133 struct list_head expiring_list;
137 static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb)
139 return (struct autofs_sb_info *)(sb->s_fs_info);
142 static inline struct autofs_info *autofs4_dentry_ino(struct dentry *dentry)
144 return (struct autofs_info *)(dentry->d_fsdata);
147 /* autofs4_oz_mode(): do we see the man behind the curtain? (The
148 processes which do manipulations for us in user space sees the raw
149 filesystem without "magic".) */
151 static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) {
152 return sbi->catatonic || task_pgrp(current) == sbi->oz_pgrp;
155 struct inode *autofs4_get_inode(struct super_block *, umode_t);
156 void autofs4_free_ino(struct autofs_info *);
159 int is_autofs4_dentry(struct dentry *);
160 int autofs4_expire_wait(struct dentry *dentry, int rcu_walk);
161 int autofs4_expire_run(struct super_block *, struct vfsmount *,
162 struct autofs_sb_info *,
163 struct autofs_packet_expire __user *);
164 int autofs4_do_expire_multi(struct super_block *sb, struct vfsmount *mnt,
165 struct autofs_sb_info *sbi, int when);
166 int autofs4_expire_multi(struct super_block *, struct vfsmount *,
167 struct autofs_sb_info *, int __user *);
168 struct dentry *autofs4_expire_direct(struct super_block *sb,
169 struct vfsmount *mnt,
170 struct autofs_sb_info *sbi, int how);
171 struct dentry *autofs4_expire_indirect(struct super_block *sb,
172 struct vfsmount *mnt,
173 struct autofs_sb_info *sbi, int how);
175 /* Device node initialization */
177 int autofs_dev_ioctl_init(void);
178 void autofs_dev_ioctl_exit(void);
180 /* Operations structures */
182 extern const struct inode_operations autofs4_symlink_inode_operations;
183 extern const struct inode_operations autofs4_dir_inode_operations;
184 extern const struct file_operations autofs4_dir_operations;
185 extern const struct file_operations autofs4_root_operations;
186 extern const struct dentry_operations autofs4_dentry_operations;
188 /* VFS automount flags management functions */
189 static inline void __managed_dentry_set_managed(struct dentry *dentry)
191 dentry->d_flags |= (DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT);
194 static inline void managed_dentry_set_managed(struct dentry *dentry)
196 spin_lock(&dentry->d_lock);
197 __managed_dentry_set_managed(dentry);
198 spin_unlock(&dentry->d_lock);
201 static inline void __managed_dentry_clear_managed(struct dentry *dentry)
203 dentry->d_flags &= ~(DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT);
206 static inline void managed_dentry_clear_managed(struct dentry *dentry)
208 spin_lock(&dentry->d_lock);
209 __managed_dentry_clear_managed(dentry);
210 spin_unlock(&dentry->d_lock);
213 /* Initializing function */
215 int autofs4_fill_super(struct super_block *, void *, int);
216 struct autofs_info *autofs4_new_ino(struct autofs_sb_info *);
217 void autofs4_clean_ino(struct autofs_info *);
219 static inline int autofs_prepare_pipe(struct file *pipe)
221 if (!(pipe->f_mode & FMODE_CAN_WRITE))
223 if (!S_ISFIFO(file_inode(pipe)->i_mode))
225 /* We want a packet pipe */
226 pipe->f_flags |= O_DIRECT;
230 /* Queue management functions */
232 int autofs4_wait(struct autofs_sb_info *,struct dentry *, enum autofs_notify);
233 int autofs4_wait_release(struct autofs_sb_info *,autofs_wqt_t,int);
234 void autofs4_catatonic_mode(struct autofs_sb_info *);
236 static inline u32 autofs4_get_dev(struct autofs_sb_info *sbi)
238 return new_encode_dev(sbi->sb->s_dev);
241 static inline u64 autofs4_get_ino(struct autofs_sb_info *sbi)
243 return d_inode(sbi->sb->s_root)->i_ino;
246 static inline void __autofs4_add_expiring(struct dentry *dentry)
248 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
249 struct autofs_info *ino = autofs4_dentry_ino(dentry);
251 if (list_empty(&ino->expiring))
252 list_add(&ino->expiring, &sbi->expiring_list);
257 static inline void autofs4_add_expiring(struct dentry *dentry)
259 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
260 struct autofs_info *ino = autofs4_dentry_ino(dentry);
262 spin_lock(&sbi->lookup_lock);
263 if (list_empty(&ino->expiring))
264 list_add(&ino->expiring, &sbi->expiring_list);
265 spin_unlock(&sbi->lookup_lock);
270 static inline void autofs4_del_expiring(struct dentry *dentry)
272 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
273 struct autofs_info *ino = autofs4_dentry_ino(dentry);
275 spin_lock(&sbi->lookup_lock);
276 if (!list_empty(&ino->expiring))
277 list_del_init(&ino->expiring);
278 spin_unlock(&sbi->lookup_lock);
283 extern void autofs4_kill_sb(struct super_block *);