Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* -*- c -*- ------------------------------------------------------------- * |
| 2 | * |
| 3 | * linux/fs/autofs/autofs_i.h |
| 4 | * |
| 5 | * Copyright 1997-1998 Transmeta Corporation - All Rights Reserved |
Ian Kent | 34ca959 | 2006-03-27 01:14:54 -0800 | [diff] [blame] | 6 | * Copyright 2005-2006 Ian Kent <raven@themaw.net> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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> |
Ian Kent | 8d7b48e | 2008-10-15 22:02:54 -0700 | [diff] [blame] | 17 | #include <linux/auto_dev-ioctl.h> |
Ingo Molnar | 1d5599e | 2006-03-23 03:00:41 -0800 | [diff] [blame] | 18 | #include <linux/mutex.h> |
Nick Piggin | b5c84bf | 2011-01-07 17:49:38 +1100 | [diff] [blame] | 19 | #include <linux/spinlock.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | #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 Kent | 8d7b48e | 2008-10-15 22:02:54 -0700 | [diff] [blame] | 26 | #define AUTOFS_DEV_IOCTL_IOC_FIRST (AUTOFS_DEV_IOCTL_VERSION) |
| 27 | #define AUTOFS_DEV_IOCTL_IOC_COUNT (AUTOFS_IOC_COUNT - 11) |
| 28 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 <asm/current.h> |
| 38 | #include <asm/uaccess.h> |
| 39 | |
| 40 | /* #define DEBUG */ |
| 41 | |
| 42 | #ifdef DEBUG |
Ian Kent | 8d7b48e | 2008-10-15 22:02:54 -0700 | [diff] [blame] | 43 | #define DPRINTK(fmt, args...) \ |
| 44 | do { \ |
| 45 | printk(KERN_DEBUG "pid %d: %s: " fmt "\n", \ |
| 46 | current->pid, __func__, ##args); \ |
| 47 | } while (0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | #else |
Ian Kent | 8d7b48e | 2008-10-15 22:02:54 -0700 | [diff] [blame] | 49 | #define DPRINTK(fmt, args...) do {} while (0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | #endif |
| 51 | |
Ian Kent | 8d7b48e | 2008-10-15 22:02:54 -0700 | [diff] [blame] | 52 | #define AUTOFS_WARN(fmt, args...) \ |
| 53 | do { \ |
| 54 | printk(KERN_WARNING "pid %d: %s: " fmt "\n", \ |
| 55 | current->pid, __func__, ##args); \ |
| 56 | } while (0) |
| 57 | |
| 58 | #define AUTOFS_ERROR(fmt, args...) \ |
| 59 | do { \ |
| 60 | printk(KERN_ERR "pid %d: %s: " fmt "\n", \ |
| 61 | current->pid, __func__, ##args); \ |
| 62 | } while (0) |
| 63 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 64 | /* Unified info structure. This is pointed to by both the dentry and |
| 65 | inode structures. Each file in the filesystem has an instance of this |
| 66 | structure. It holds a reference to the dentry, so dentries are never |
| 67 | flushed while the file exists. All name lookups are dealt with at the |
| 68 | dentry level, although the filesystem can interfere in the validation |
| 69 | process. Readdir is implemented by traversing the dentry lists. */ |
| 70 | struct autofs_info { |
| 71 | struct dentry *dentry; |
| 72 | struct inode *inode; |
| 73 | |
| 74 | int flags; |
| 75 | |
Ian Kent | 6e60a9a | 2008-07-23 21:30:27 -0700 | [diff] [blame] | 76 | struct completion expire_complete; |
| 77 | |
Ian Kent | 2576737 | 2008-07-23 21:30:12 -0700 | [diff] [blame] | 78 | struct list_head active; |
Ian Kent | 4f8427d | 2009-12-15 16:45:42 -0800 | [diff] [blame] | 79 | int active_count; |
| 80 | |
Ian Kent | 5f6f4f2 | 2008-07-23 21:30:09 -0700 | [diff] [blame] | 81 | struct list_head expiring; |
Ian Kent | f50b6f8 | 2007-02-20 13:58:10 -0800 | [diff] [blame] | 82 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 83 | struct autofs_sb_info *sbi; |
| 84 | unsigned long last_used; |
Ian Kent | 1aff3c8 | 2006-03-27 01:14:46 -0800 | [diff] [blame] | 85 | atomic_t count; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 86 | |
Ian Kent | c0f54d3 | 2008-10-15 22:02:52 -0700 | [diff] [blame] | 87 | uid_t uid; |
| 88 | gid_t gid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | }; |
| 90 | |
| 91 | #define AUTOFS_INF_EXPIRING (1<<0) /* dentry is in the process of expiring */ |
Ian Kent | aa952eb | 2009-12-15 16:45:45 -0800 | [diff] [blame] | 92 | #define AUTOFS_INF_PENDING (1<<2) /* dentry pending mount */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 93 | |
| 94 | struct autofs_wait_queue { |
| 95 | wait_queue_head_t queue; |
| 96 | struct autofs_wait_queue *next; |
| 97 | autofs_wqt_t wait_queue_token; |
| 98 | /* We use the following to see what we are waiting for */ |
Jeff Moyer | 70b52a0 | 2008-07-23 21:30:16 -0700 | [diff] [blame] | 99 | struct qstr name; |
Ian Kent | 5c0a32f | 2006-03-27 01:14:55 -0800 | [diff] [blame] | 100 | u32 dev; |
| 101 | u64 ino; |
| 102 | uid_t uid; |
| 103 | gid_t gid; |
| 104 | pid_t pid; |
| 105 | pid_t tgid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | /* This is for status reporting upon return */ |
| 107 | int status; |
Ian Kent | 296f7bf | 2008-07-23 21:30:21 -0700 | [diff] [blame] | 108 | unsigned int wait_ctr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 109 | }; |
| 110 | |
| 111 | #define AUTOFS_SBI_MAGIC 0x6d4a556d |
| 112 | |
| 113 | struct autofs_sb_info { |
| 114 | u32 magic; |
Ian Kent | d7c4a5f | 2006-03-27 01:14:49 -0800 | [diff] [blame] | 115 | int pipefd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | struct file *pipe; |
| 117 | pid_t oz_pgrp; |
| 118 | int catatonic; |
| 119 | int version; |
| 120 | int sub_version; |
Ian Kent | d7c4a5f | 2006-03-27 01:14:49 -0800 | [diff] [blame] | 121 | int min_proto; |
| 122 | int max_proto; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 123 | unsigned long exp_timeout; |
Ian Kent | 34ca959 | 2006-03-27 01:14:54 -0800 | [diff] [blame] | 124 | unsigned int type; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 125 | int reghost_enabled; |
| 126 | int needs_reghost; |
| 127 | struct super_block *sb; |
Ingo Molnar | 1d5599e | 2006-03-23 03:00:41 -0800 | [diff] [blame] | 128 | struct mutex wq_mutex; |
Ian Kent | 3a9720c | 2005-05-01 08:59:17 -0700 | [diff] [blame] | 129 | spinlock_t fs_lock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | struct autofs_wait_queue *queues; /* Wait queue pointer */ |
Ian Kent | 5f6f4f2 | 2008-07-23 21:30:09 -0700 | [diff] [blame] | 131 | spinlock_t lookup_lock; |
Ian Kent | 2576737 | 2008-07-23 21:30:12 -0700 | [diff] [blame] | 132 | struct list_head active_list; |
Ian Kent | 5f6f4f2 | 2008-07-23 21:30:09 -0700 | [diff] [blame] | 133 | struct list_head expiring_list; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | }; |
| 135 | |
| 136 | static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb) |
| 137 | { |
| 138 | return (struct autofs_sb_info *)(sb->s_fs_info); |
| 139 | } |
| 140 | |
| 141 | static inline struct autofs_info *autofs4_dentry_ino(struct dentry *dentry) |
| 142 | { |
| 143 | return (struct autofs_info *)(dentry->d_fsdata); |
| 144 | } |
| 145 | |
| 146 | /* autofs4_oz_mode(): do we see the man behind the curtain? (The |
| 147 | processes which do manipulations for us in user space sees the raw |
| 148 | filesystem without "magic".) */ |
| 149 | |
| 150 | static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) { |
Pavel Emelianov | a47afb0 | 2007-10-18 23:39:46 -0700 | [diff] [blame] | 151 | return sbi->catatonic || task_pgrp_nr(current) == sbi->oz_pgrp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | } |
| 153 | |
| 154 | /* Does a dentry have some pending activity? */ |
| 155 | static inline int autofs4_ispending(struct dentry *dentry) |
| 156 | { |
| 157 | struct autofs_info *inf = autofs4_dentry_ino(dentry); |
| 158 | |
Ian Kent | aa952eb | 2009-12-15 16:45:45 -0800 | [diff] [blame] | 159 | if (inf->flags & AUTOFS_INF_PENDING) |
Ian Kent | 3a9720c | 2005-05-01 08:59:17 -0700 | [diff] [blame] | 160 | return 1; |
| 161 | |
Ian Kent | 97e7449 | 2008-07-23 21:30:26 -0700 | [diff] [blame] | 162 | if (inf->flags & AUTOFS_INF_EXPIRING) |
| 163 | return 1; |
Ian Kent | 3a9720c | 2005-05-01 08:59:17 -0700 | [diff] [blame] | 164 | |
Ian Kent | 97e7449 | 2008-07-23 21:30:26 -0700 | [diff] [blame] | 165 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 166 | } |
| 167 | |
Al Viro | 726a5e0 | 2011-01-16 17:43:52 -0500 | [diff] [blame] | 168 | struct inode *autofs4_get_inode(struct super_block *, mode_t); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 169 | void autofs4_free_ino(struct autofs_info *); |
| 170 | |
| 171 | /* Expiration */ |
| 172 | int is_autofs4_dentry(struct dentry *); |
Ian Kent | 06a3598 | 2008-07-23 21:30:28 -0700 | [diff] [blame] | 173 | int autofs4_expire_wait(struct dentry *dentry); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 174 | int autofs4_expire_run(struct super_block *, struct vfsmount *, |
| 175 | struct autofs_sb_info *, |
| 176 | struct autofs_packet_expire __user *); |
Ian Kent | 56fcef7 | 2009-03-31 15:24:43 -0700 | [diff] [blame] | 177 | int autofs4_do_expire_multi(struct super_block *sb, struct vfsmount *mnt, |
| 178 | struct autofs_sb_info *sbi, int when); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 179 | int autofs4_expire_multi(struct super_block *, struct vfsmount *, |
| 180 | struct autofs_sb_info *, int __user *); |
Ian Kent | 8d7b48e | 2008-10-15 22:02:54 -0700 | [diff] [blame] | 181 | struct dentry *autofs4_expire_direct(struct super_block *sb, |
| 182 | struct vfsmount *mnt, |
| 183 | struct autofs_sb_info *sbi, int how); |
| 184 | struct dentry *autofs4_expire_indirect(struct super_block *sb, |
| 185 | struct vfsmount *mnt, |
| 186 | struct autofs_sb_info *sbi, int how); |
| 187 | |
| 188 | /* Device node initialization */ |
| 189 | |
| 190 | int autofs_dev_ioctl_init(void); |
| 191 | void autofs_dev_ioctl_exit(void); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 192 | |
| 193 | /* Operations structures */ |
| 194 | |
Arjan van de Ven | 754661f | 2007-02-12 00:55:38 -0800 | [diff] [blame] | 195 | extern const struct inode_operations autofs4_symlink_inode_operations; |
| 196 | extern const struct inode_operations autofs4_dir_inode_operations; |
Arjan van de Ven | 4b6f5d2 | 2006-03-28 01:56:42 -0800 | [diff] [blame] | 197 | extern const struct file_operations autofs4_dir_operations; |
| 198 | extern const struct file_operations autofs4_root_operations; |
Ian Kent | 71e469d | 2011-01-14 18:46:19 +0000 | [diff] [blame] | 199 | extern const struct dentry_operations autofs4_dentry_operations; |
Ian Kent | 1058421 | 2011-01-14 18:45:58 +0000 | [diff] [blame] | 200 | |
| 201 | /* VFS automount flags management functions */ |
| 202 | |
| 203 | static inline void __managed_dentry_set_automount(struct dentry *dentry) |
| 204 | { |
| 205 | dentry->d_flags |= DCACHE_NEED_AUTOMOUNT; |
| 206 | } |
| 207 | |
| 208 | static inline void managed_dentry_set_automount(struct dentry *dentry) |
| 209 | { |
| 210 | spin_lock(&dentry->d_lock); |
| 211 | __managed_dentry_set_automount(dentry); |
| 212 | spin_unlock(&dentry->d_lock); |
| 213 | } |
| 214 | |
| 215 | static inline void __managed_dentry_clear_automount(struct dentry *dentry) |
| 216 | { |
| 217 | dentry->d_flags &= ~DCACHE_NEED_AUTOMOUNT; |
| 218 | } |
| 219 | |
| 220 | static inline void managed_dentry_clear_automount(struct dentry *dentry) |
| 221 | { |
| 222 | spin_lock(&dentry->d_lock); |
| 223 | __managed_dentry_clear_automount(dentry); |
| 224 | spin_unlock(&dentry->d_lock); |
| 225 | } |
| 226 | |
Ian Kent | b5b8017 | 2011-01-14 18:46:03 +0000 | [diff] [blame] | 227 | static inline void __managed_dentry_set_transit(struct dentry *dentry) |
| 228 | { |
| 229 | dentry->d_flags |= DCACHE_MANAGE_TRANSIT; |
| 230 | } |
| 231 | |
| 232 | static inline void managed_dentry_set_transit(struct dentry *dentry) |
| 233 | { |
| 234 | spin_lock(&dentry->d_lock); |
| 235 | __managed_dentry_set_transit(dentry); |
| 236 | spin_unlock(&dentry->d_lock); |
| 237 | } |
| 238 | |
| 239 | static inline void __managed_dentry_clear_transit(struct dentry *dentry) |
| 240 | { |
| 241 | dentry->d_flags &= ~DCACHE_MANAGE_TRANSIT; |
| 242 | } |
| 243 | |
| 244 | static inline void managed_dentry_clear_transit(struct dentry *dentry) |
| 245 | { |
| 246 | spin_lock(&dentry->d_lock); |
| 247 | __managed_dentry_clear_transit(dentry); |
| 248 | spin_unlock(&dentry->d_lock); |
| 249 | } |
| 250 | |
| 251 | static inline void __managed_dentry_set_managed(struct dentry *dentry) |
| 252 | { |
| 253 | dentry->d_flags |= (DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT); |
| 254 | } |
| 255 | |
| 256 | static inline void managed_dentry_set_managed(struct dentry *dentry) |
| 257 | { |
| 258 | spin_lock(&dentry->d_lock); |
| 259 | __managed_dentry_set_managed(dentry); |
| 260 | spin_unlock(&dentry->d_lock); |
| 261 | } |
| 262 | |
| 263 | static inline void __managed_dentry_clear_managed(struct dentry *dentry) |
| 264 | { |
| 265 | dentry->d_flags &= ~(DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT); |
| 266 | } |
| 267 | |
| 268 | static inline void managed_dentry_clear_managed(struct dentry *dentry) |
| 269 | { |
| 270 | spin_lock(&dentry->d_lock); |
| 271 | __managed_dentry_clear_managed(dentry); |
| 272 | spin_unlock(&dentry->d_lock); |
| 273 | } |
| 274 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 275 | /* Initializing function */ |
| 276 | |
| 277 | int autofs4_fill_super(struct super_block *, void *, int); |
Al Viro | 26e6c91 | 2011-01-16 18:43:40 -0500 | [diff] [blame] | 278 | struct autofs_info *autofs4_new_ino(struct autofs_sb_info *); |
| 279 | void autofs4_clean_ino(struct autofs_info *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 280 | |
| 281 | /* Queue management functions */ |
| 282 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 283 | int autofs4_wait(struct autofs_sb_info *,struct dentry *, enum autofs_notify); |
| 284 | int autofs4_wait_release(struct autofs_sb_info *,autofs_wqt_t,int); |
| 285 | void autofs4_catatonic_mode(struct autofs_sb_info *); |
| 286 | |
Ian Kent | 5c0a32f | 2006-03-27 01:14:55 -0800 | [diff] [blame] | 287 | static inline u32 autofs4_get_dev(struct autofs_sb_info *sbi) |
| 288 | { |
| 289 | return new_encode_dev(sbi->sb->s_dev); |
| 290 | } |
| 291 | |
| 292 | static inline u64 autofs4_get_ino(struct autofs_sb_info *sbi) |
| 293 | { |
| 294 | return sbi->sb->s_root->d_inode->i_ino; |
| 295 | } |
| 296 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 297 | static inline int simple_positive(struct dentry *dentry) |
| 298 | { |
| 299 | return dentry->d_inode && !d_unhashed(dentry); |
| 300 | } |
| 301 | |
Nick Piggin | 2fd6b7f | 2011-01-07 17:49:34 +1100 | [diff] [blame] | 302 | static inline void __autofs4_add_expiring(struct dentry *dentry) |
| 303 | { |
| 304 | struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); |
| 305 | struct autofs_info *ino = autofs4_dentry_ino(dentry); |
| 306 | if (ino) { |
| 307 | if (list_empty(&ino->expiring)) |
| 308 | list_add(&ino->expiring, &sbi->expiring_list); |
| 309 | } |
| 310 | return; |
| 311 | } |
| 312 | |
Ian Kent | c4cd70b | 2009-12-15 16:45:43 -0800 | [diff] [blame] | 313 | static inline void autofs4_add_expiring(struct dentry *dentry) |
| 314 | { |
| 315 | struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); |
| 316 | struct autofs_info *ino = autofs4_dentry_ino(dentry); |
| 317 | if (ino) { |
| 318 | spin_lock(&sbi->lookup_lock); |
| 319 | if (list_empty(&ino->expiring)) |
| 320 | list_add(&ino->expiring, &sbi->expiring_list); |
| 321 | spin_unlock(&sbi->lookup_lock); |
| 322 | } |
| 323 | return; |
| 324 | } |
| 325 | |
| 326 | static inline void autofs4_del_expiring(struct dentry *dentry) |
| 327 | { |
| 328 | struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); |
| 329 | struct autofs_info *ino = autofs4_dentry_ino(dentry); |
| 330 | if (ino) { |
| 331 | spin_lock(&sbi->lookup_lock); |
| 332 | if (!list_empty(&ino->expiring)) |
| 333 | list_del_init(&ino->expiring); |
| 334 | spin_unlock(&sbi->lookup_lock); |
| 335 | } |
| 336 | return; |
| 337 | } |
| 338 | |
David Howells | 6ce3152 | 2006-10-11 01:22:15 -0700 | [diff] [blame] | 339 | extern void autofs4_kill_sb(struct super_block *); |