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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* -*- c -*- ------------------------------------------------------------- *
2 *
3 * linux/fs/autofs/autofs_i.h
4 *
5 * Copyright 1997-1998 Transmeta Corporation - All Rights Reserved
Ian Kent34ca9592006-03-27 01:14:54 -08006 * Copyright 2005-2006 Ian Kent <raven@themaw.net>
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 *
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>
Ian Kent8d7b48e2008-10-15 22:02:54 -070017#include <linux/auto_dev-ioctl.h>
Ingo Molnar1d5599e2006-03-23 03:00:41 -080018#include <linux/mutex.h>
Nick Pigginb5c84bf2011-01-07 17:49:38 +110019#include <linux/spinlock.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <linux/list.h>
21
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
25
Ian Kent8d7b48e2008-10-15 22:02:54 -070026#define AUTOFS_DEV_IOCTL_IOC_FIRST (AUTOFS_DEV_IOCTL_VERSION)
27#define AUTOFS_DEV_IOCTL_IOC_COUNT (AUTOFS_IOC_COUNT - 11)
28
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#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 <asm/current.h>
38#include <asm/uaccess.h>
39
40/* #define DEBUG */
41
Linus Torvaldsc3ad9962011-08-08 11:35:17 -070042#define DPRINTK(fmt, ...) \
43 pr_debug("pid %d: %s: " fmt "\n", \
44 current->pid, __func__, ##__VA_ARGS__)
Linus Torvalds1da177e2005-04-16 15:20:36 -070045
Linus Torvaldsc3ad9962011-08-08 11:35:17 -070046#define AUTOFS_WARN(fmt, ...) \
Ian Kent8d7b48e2008-10-15 22:02:54 -070047 printk(KERN_WARNING "pid %d: %s: " fmt "\n", \
Linus Torvaldsc3ad9962011-08-08 11:35:17 -070048 current->pid, __func__, ##__VA_ARGS__)
Ian Kent8d7b48e2008-10-15 22:02:54 -070049
Linus Torvaldsc3ad9962011-08-08 11:35:17 -070050#define AUTOFS_ERROR(fmt, ...) \
Ian Kent8d7b48e2008-10-15 22:02:54 -070051 printk(KERN_ERR "pid %d: %s: " fmt "\n", \
Linus Torvaldsc3ad9962011-08-08 11:35:17 -070052 current->pid, __func__, ##__VA_ARGS__)
Ian Kent8d7b48e2008-10-15 22:02:54 -070053
Linus Torvalds1da177e2005-04-16 15:20:36 -070054/* Unified info structure. This is pointed to by both the dentry and
55 inode structures. Each file in the filesystem has an instance of this
56 structure. It holds a reference to the dentry, so dentries are never
57 flushed while the file exists. All name lookups are dealt with at the
58 dentry level, although the filesystem can interfere in the validation
59 process. Readdir is implemented by traversing the dentry lists. */
60struct autofs_info {
61 struct dentry *dentry;
62 struct inode *inode;
63
64 int flags;
65
Ian Kent6e60a9a2008-07-23 21:30:27 -070066 struct completion expire_complete;
67
Ian Kent25767372008-07-23 21:30:12 -070068 struct list_head active;
Ian Kent4f8427d2009-12-15 16:45:42 -080069 int active_count;
70
Ian Kent5f6f4f22008-07-23 21:30:09 -070071 struct list_head expiring;
Ian Kentf50b6f82007-02-20 13:58:10 -080072
Linus Torvalds1da177e2005-04-16 15:20:36 -070073 struct autofs_sb_info *sbi;
74 unsigned long last_used;
Ian Kent1aff3c82006-03-27 01:14:46 -080075 atomic_t count;
Linus Torvalds1da177e2005-04-16 15:20:36 -070076
Eric W. Biederman45634cd2012-02-07 16:18:52 -080077 kuid_t uid;
78 kgid_t gid;
Linus Torvalds1da177e2005-04-16 15:20:36 -070079};
80
81#define AUTOFS_INF_EXPIRING (1<<0) /* dentry is in the process of expiring */
Ian Kentaa952eb2009-12-15 16:45:45 -080082#define AUTOFS_INF_PENDING (1<<2) /* dentry pending mount */
Linus Torvalds1da177e2005-04-16 15:20:36 -070083
84struct autofs_wait_queue {
85 wait_queue_head_t queue;
86 struct autofs_wait_queue *next;
87 autofs_wqt_t wait_queue_token;
88 /* We use the following to see what we are waiting for */
Jeff Moyer70b52a02008-07-23 21:30:16 -070089 struct qstr name;
Ian Kent5c0a32f2006-03-27 01:14:55 -080090 u32 dev;
91 u64 ino;
Eric W. Biederman45634cd2012-02-07 16:18:52 -080092 kuid_t uid;
93 kgid_t gid;
Ian Kent5c0a32f2006-03-27 01:14:55 -080094 pid_t pid;
95 pid_t tgid;
Linus Torvalds1da177e2005-04-16 15:20:36 -070096 /* This is for status reporting upon return */
97 int status;
Ian Kent296f7bf2008-07-23 21:30:21 -070098 unsigned int wait_ctr;
Linus Torvalds1da177e2005-04-16 15:20:36 -070099};
100
101#define AUTOFS_SBI_MAGIC 0x6d4a556d
102
103struct autofs_sb_info {
104 u32 magic;
Ian Kentd7c4a5f2006-03-27 01:14:49 -0800105 int pipefd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106 struct file *pipe;
107 pid_t oz_pgrp;
108 int catatonic;
109 int version;
110 int sub_version;
Ian Kentd7c4a5f2006-03-27 01:14:49 -0800111 int min_proto;
112 int max_proto;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113 unsigned long exp_timeout;
Ian Kent34ca9592006-03-27 01:14:54 -0800114 unsigned int type;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 int reghost_enabled;
116 int needs_reghost;
117 struct super_block *sb;
Ingo Molnar1d5599e2006-03-23 03:00:41 -0800118 struct mutex wq_mutex;
Al Virod668dc52012-01-10 22:35:38 -0500119 struct mutex pipe_mutex;
Ian Kent3a9720c2005-05-01 08:59:17 -0700120 spinlock_t fs_lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121 struct autofs_wait_queue *queues; /* Wait queue pointer */
Ian Kent5f6f4f22008-07-23 21:30:09 -0700122 spinlock_t lookup_lock;
Ian Kent25767372008-07-23 21:30:12 -0700123 struct list_head active_list;
Ian Kent5f6f4f22008-07-23 21:30:09 -0700124 struct list_head expiring_list;
Al Virobaa40672013-10-03 12:46:44 -0400125 struct rcu_head rcu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126};
127
128static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb)
129{
130 return (struct autofs_sb_info *)(sb->s_fs_info);
131}
132
133static inline struct autofs_info *autofs4_dentry_ino(struct dentry *dentry)
134{
135 return (struct autofs_info *)(dentry->d_fsdata);
136}
137
138/* autofs4_oz_mode(): do we see the man behind the curtain? (The
139 processes which do manipulations for us in user space sees the raw
140 filesystem without "magic".) */
141
142static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) {
Pavel Emelianova47afb02007-10-18 23:39:46 -0700143 return sbi->catatonic || task_pgrp_nr(current) == sbi->oz_pgrp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144}
145
146/* Does a dentry have some pending activity? */
147static inline int autofs4_ispending(struct dentry *dentry)
148{
149 struct autofs_info *inf = autofs4_dentry_ino(dentry);
150
Ian Kentaa952eb2009-12-15 16:45:45 -0800151 if (inf->flags & AUTOFS_INF_PENDING)
Ian Kent3a9720c2005-05-01 08:59:17 -0700152 return 1;
153
Ian Kent97e74492008-07-23 21:30:26 -0700154 if (inf->flags & AUTOFS_INF_EXPIRING)
155 return 1;
Ian Kent3a9720c2005-05-01 08:59:17 -0700156
Ian Kent97e74492008-07-23 21:30:26 -0700157 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158}
159
Al Viro030a8ba2011-07-26 03:29:03 -0400160struct inode *autofs4_get_inode(struct super_block *, umode_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161void autofs4_free_ino(struct autofs_info *);
162
163/* Expiration */
164int is_autofs4_dentry(struct dentry *);
Ian Kent06a35982008-07-23 21:30:28 -0700165int autofs4_expire_wait(struct dentry *dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166int autofs4_expire_run(struct super_block *, struct vfsmount *,
167 struct autofs_sb_info *,
168 struct autofs_packet_expire __user *);
Ian Kent56fcef72009-03-31 15:24:43 -0700169int autofs4_do_expire_multi(struct super_block *sb, struct vfsmount *mnt,
170 struct autofs_sb_info *sbi, int when);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171int autofs4_expire_multi(struct super_block *, struct vfsmount *,
172 struct autofs_sb_info *, int __user *);
Ian Kent8d7b48e2008-10-15 22:02:54 -0700173struct dentry *autofs4_expire_direct(struct super_block *sb,
174 struct vfsmount *mnt,
175 struct autofs_sb_info *sbi, int how);
176struct dentry *autofs4_expire_indirect(struct super_block *sb,
177 struct vfsmount *mnt,
178 struct autofs_sb_info *sbi, int how);
179
180/* Device node initialization */
181
182int autofs_dev_ioctl_init(void);
183void autofs_dev_ioctl_exit(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184
185/* Operations structures */
186
Arjan van de Ven754661f2007-02-12 00:55:38 -0800187extern const struct inode_operations autofs4_symlink_inode_operations;
188extern const struct inode_operations autofs4_dir_inode_operations;
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -0800189extern const struct file_operations autofs4_dir_operations;
190extern const struct file_operations autofs4_root_operations;
Ian Kent71e469d2011-01-14 18:46:19 +0000191extern const struct dentry_operations autofs4_dentry_operations;
Ian Kent10584212011-01-14 18:45:58 +0000192
193/* VFS automount flags management functions */
194
195static inline void __managed_dentry_set_automount(struct dentry *dentry)
196{
197 dentry->d_flags |= DCACHE_NEED_AUTOMOUNT;
198}
199
200static inline void managed_dentry_set_automount(struct dentry *dentry)
201{
202 spin_lock(&dentry->d_lock);
203 __managed_dentry_set_automount(dentry);
204 spin_unlock(&dentry->d_lock);
205}
206
207static inline void __managed_dentry_clear_automount(struct dentry *dentry)
208{
209 dentry->d_flags &= ~DCACHE_NEED_AUTOMOUNT;
210}
211
212static inline void managed_dentry_clear_automount(struct dentry *dentry)
213{
214 spin_lock(&dentry->d_lock);
215 __managed_dentry_clear_automount(dentry);
216 spin_unlock(&dentry->d_lock);
217}
218
Ian Kentb5b80172011-01-14 18:46:03 +0000219static inline void __managed_dentry_set_transit(struct dentry *dentry)
220{
221 dentry->d_flags |= DCACHE_MANAGE_TRANSIT;
222}
223
224static inline void managed_dentry_set_transit(struct dentry *dentry)
225{
226 spin_lock(&dentry->d_lock);
227 __managed_dentry_set_transit(dentry);
228 spin_unlock(&dentry->d_lock);
229}
230
231static inline void __managed_dentry_clear_transit(struct dentry *dentry)
232{
233 dentry->d_flags &= ~DCACHE_MANAGE_TRANSIT;
234}
235
236static inline void managed_dentry_clear_transit(struct dentry *dentry)
237{
238 spin_lock(&dentry->d_lock);
239 __managed_dentry_clear_transit(dentry);
240 spin_unlock(&dentry->d_lock);
241}
242
243static inline void __managed_dentry_set_managed(struct dentry *dentry)
244{
245 dentry->d_flags |= (DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT);
246}
247
248static inline void managed_dentry_set_managed(struct dentry *dentry)
249{
250 spin_lock(&dentry->d_lock);
251 __managed_dentry_set_managed(dentry);
252 spin_unlock(&dentry->d_lock);
253}
254
255static inline void __managed_dentry_clear_managed(struct dentry *dentry)
256{
257 dentry->d_flags &= ~(DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT);
258}
259
260static inline void managed_dentry_clear_managed(struct dentry *dentry)
261{
262 spin_lock(&dentry->d_lock);
263 __managed_dentry_clear_managed(dentry);
264 spin_unlock(&dentry->d_lock);
265}
266
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267/* Initializing function */
268
269int autofs4_fill_super(struct super_block *, void *, int);
Al Viro26e6c912011-01-16 18:43:40 -0500270struct autofs_info *autofs4_new_ino(struct autofs_sb_info *);
271void autofs4_clean_ino(struct autofs_info *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272
Linus Torvalds64f371b2012-04-29 13:30:08 -0700273static inline int autofs_prepare_pipe(struct file *pipe)
274{
Al Viro72c2d532013-09-22 16:27:52 -0400275 if (!pipe->f_op->write)
Linus Torvalds64f371b2012-04-29 13:30:08 -0700276 return -EINVAL;
Al Viro496ad9a2013-01-23 17:07:38 -0500277 if (!S_ISFIFO(file_inode(pipe)->i_mode))
Linus Torvalds64f371b2012-04-29 13:30:08 -0700278 return -EINVAL;
279 /* We want a packet pipe */
280 pipe->f_flags |= O_DIRECT;
281 return 0;
282}
283
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284/* Queue management functions */
285
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286int autofs4_wait(struct autofs_sb_info *,struct dentry *, enum autofs_notify);
287int autofs4_wait_release(struct autofs_sb_info *,autofs_wqt_t,int);
288void autofs4_catatonic_mode(struct autofs_sb_info *);
289
Ian Kent5c0a32f2006-03-27 01:14:55 -0800290static inline u32 autofs4_get_dev(struct autofs_sb_info *sbi)
291{
292 return new_encode_dev(sbi->sb->s_dev);
293}
294
295static inline u64 autofs4_get_ino(struct autofs_sb_info *sbi)
296{
297 return sbi->sb->s_root->d_inode->i_ino;
298}
299
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300static inline int simple_positive(struct dentry *dentry)
301{
302 return dentry->d_inode && !d_unhashed(dentry);
303}
304
Nick Piggin2fd6b7f2011-01-07 17:49:34 +1100305static inline void __autofs4_add_expiring(struct dentry *dentry)
306{
307 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
308 struct autofs_info *ino = autofs4_dentry_ino(dentry);
309 if (ino) {
310 if (list_empty(&ino->expiring))
311 list_add(&ino->expiring, &sbi->expiring_list);
312 }
313 return;
314}
315
Ian Kentc4cd70b2009-12-15 16:45:43 -0800316static inline void autofs4_add_expiring(struct dentry *dentry)
317{
318 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
319 struct autofs_info *ino = autofs4_dentry_ino(dentry);
320 if (ino) {
321 spin_lock(&sbi->lookup_lock);
322 if (list_empty(&ino->expiring))
323 list_add(&ino->expiring, &sbi->expiring_list);
324 spin_unlock(&sbi->lookup_lock);
325 }
326 return;
327}
328
329static inline void autofs4_del_expiring(struct dentry *dentry)
330{
331 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb);
332 struct autofs_info *ino = autofs4_dentry_ino(dentry);
333 if (ino) {
334 spin_lock(&sbi->lookup_lock);
335 if (!list_empty(&ino->expiring))
336 list_del_init(&ino->expiring);
337 spin_unlock(&sbi->lookup_lock);
338 }
339 return;
340}
341
David Howells6ce31522006-10-11 01:22:15 -0700342extern void autofs4_kill_sb(struct super_block *);