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/auto_dev-ioctl.h> 18#include <linux/mutex.h> 19#include <linux/list.h> 20 21/* This is the range of ioctl() numbers we claim as ours */ 22#define AUTOFS_IOC_FIRST AUTOFS_IOC_READY 23#define AUTOFS_IOC_COUNT 32 24 25#define AUTOFS_DEV_IOCTL_IOC_FIRST (AUTOFS_DEV_IOCTL_VERSION) 26#define AUTOFS_DEV_IOCTL_IOC_COUNT (AUTOFS_IOC_COUNT - 11) 27 28#include <linux/kernel.h> 29#include <linux/slab.h> 30#include <linux/time.h> 31#include <linux/string.h> 32#include <linux/wait.h> 33#include <linux/sched.h> 34#include <linux/mount.h> 35#include <linux/namei.h> 36#include <asm/current.h> 37#include <asm/uaccess.h> 38 39/* #define DEBUG */ 40 41#ifdef DEBUG 42#define DPRINTK(fmt, args...) \ 43do { \ 44 printk(KERN_DEBUG "pid %d: %s: " fmt "\n", \ 45 current->pid, __func__, ##args); \ 46} while (0) 47#else 48#define DPRINTK(fmt, args...) do {} while (0) 49#endif 50 51#define AUTOFS_WARN(fmt, args...) \ 52do { \ 53 printk(KERN_WARNING "pid %d: %s: " fmt "\n", \ 54 current->pid, __func__, ##args); \ 55} while (0) 56 57#define AUTOFS_ERROR(fmt, args...) \ 58do { \ 59 printk(KERN_ERR "pid %d: %s: " fmt "\n", \ 60 current->pid, __func__, ##args); \ 61} while (0) 62 63/* Unified info structure. This is pointed to by both the dentry and 64 inode structures. Each file in the filesystem has an instance of this 65 structure. It holds a reference to the dentry, so dentries are never 66 flushed while the file exists. All name lookups are dealt with at the 67 dentry level, although the filesystem can interfere in the validation 68 process. Readdir is implemented by traversing the dentry lists. */ 69struct autofs_info { 70 struct dentry *dentry; 71 struct inode *inode; 72 73 int flags; 74 75 struct completion expire_complete; 76 77 struct list_head active; 78 int active_count; 79 80 struct list_head expiring; 81 82 struct autofs_sb_info *sbi; 83 unsigned long last_used; 84 atomic_t count; 85 86 uid_t uid; 87 gid_t gid; 88 89 mode_t mode; 90 size_t size; 91 92 void (*free)(struct autofs_info *); 93 union { 94 const char *symlink; 95 } u; 96}; 97 98#define AUTOFS_INF_EXPIRING (1<<0) /* dentry is in the process of expiring */ 99#define AUTOFS_INF_MOUNTPOINT (1<<1) /* mountpoint status for direct expire */ 100#define AUTOFS_INF_PENDING (1<<2) /* dentry pending mount */ 101 102struct autofs_wait_queue { 103 wait_queue_head_t queue; 104 struct autofs_wait_queue *next; 105 autofs_wqt_t wait_queue_token; 106 /* We use the following to see what we are waiting for */ 107 struct qstr name; 108 u32 dev; 109 u64 ino; 110 uid_t uid; 111 gid_t gid; 112 pid_t pid; 113 pid_t tgid; 114 /* This is for status reporting upon return */ 115 int status; 116 unsigned int wait_ctr; 117}; 118 119#define AUTOFS_SBI_MAGIC 0x6d4a556d 120 121struct autofs_sb_info { 122 u32 magic; 123 int pipefd; 124 struct file *pipe; 125 pid_t oz_pgrp; 126 int catatonic; 127 int version; 128 int sub_version; 129 int min_proto; 130 int max_proto; 131 unsigned long exp_timeout; 132 unsigned int type; 133 int reghost_enabled; 134 int needs_reghost; 135 struct super_block *sb; 136 struct mutex wq_mutex; 137 spinlock_t fs_lock; 138 struct autofs_wait_queue *queues; /* Wait queue pointer */ 139 spinlock_t lookup_lock; 140 struct list_head active_list; 141 struct list_head expiring_list; 142}; 143 144static inline struct autofs_sb_info *autofs4_sbi(struct super_block *sb) 145{ 146 return (struct autofs_sb_info *)(sb->s_fs_info); 147} 148 149static inline struct autofs_info *autofs4_dentry_ino(struct dentry *dentry) 150{ 151 return (struct autofs_info *)(dentry->d_fsdata); 152} 153 154/* autofs4_oz_mode(): do we see the man behind the curtain? (The 155 processes which do manipulations for us in user space sees the raw 156 filesystem without "magic".) */ 157 158static inline int autofs4_oz_mode(struct autofs_sb_info *sbi) { 159 return sbi->catatonic || task_pgrp_nr(current) == sbi->oz_pgrp; 160} 161 162/* Does a dentry have some pending activity? */ 163static inline int autofs4_ispending(struct dentry *dentry) 164{ 165 struct autofs_info *inf = autofs4_dentry_ino(dentry); 166 167 if (inf->flags & AUTOFS_INF_PENDING) 168 return 1; 169 170 if (inf->flags & AUTOFS_INF_EXPIRING) 171 return 1; 172 173 return 0; 174} 175 176static inline void autofs4_copy_atime(struct file *src, struct file *dst) 177{ 178 dst->f_path.dentry->d_inode->i_atime = 179 src->f_path.dentry->d_inode->i_atime; 180 return; 181} 182 183struct inode *autofs4_get_inode(struct super_block *, struct autofs_info *); 184void autofs4_free_ino(struct autofs_info *); 185 186/* Expiration */ 187int is_autofs4_dentry(struct dentry *); 188int autofs4_expire_wait(struct dentry *dentry); 189int autofs4_expire_run(struct super_block *, struct vfsmount *, 190 struct autofs_sb_info *, 191 struct autofs_packet_expire __user *); 192int autofs4_do_expire_multi(struct super_block *sb, struct vfsmount *mnt, 193 struct autofs_sb_info *sbi, int when); 194int autofs4_expire_multi(struct super_block *, struct vfsmount *, 195 struct autofs_sb_info *, int __user *); 196struct dentry *autofs4_expire_direct(struct super_block *sb, 197 struct vfsmount *mnt, 198 struct autofs_sb_info *sbi, int how); 199struct dentry *autofs4_expire_indirect(struct super_block *sb, 200 struct vfsmount *mnt, 201 struct autofs_sb_info *sbi, int how); 202 203/* Device node initialization */ 204 205int autofs_dev_ioctl_init(void); 206void autofs_dev_ioctl_exit(void); 207 208/* Operations structures */ 209 210extern const struct inode_operations autofs4_symlink_inode_operations; 211extern const struct inode_operations autofs4_dir_inode_operations; 212extern const struct inode_operations autofs4_root_inode_operations; 213extern const struct inode_operations autofs4_indirect_root_inode_operations; 214extern const struct inode_operations autofs4_direct_root_inode_operations; 215extern const struct file_operations autofs4_dir_operations; 216extern const struct file_operations autofs4_root_operations; 217 218/* Initializing function */ 219 220int autofs4_fill_super(struct super_block *, void *, int); 221struct autofs_info *autofs4_init_ino(struct autofs_info *, struct autofs_sb_info *sbi, mode_t mode); 222 223/* Queue management functions */ 224 225int autofs4_wait(struct autofs_sb_info *,struct dentry *, enum autofs_notify); 226int autofs4_wait_release(struct autofs_sb_info *,autofs_wqt_t,int); 227void autofs4_catatonic_mode(struct autofs_sb_info *); 228 229static inline int autofs4_follow_mount(struct path *path) 230{ 231 int res = 0; 232 233 while (d_mountpoint(path->dentry)) { 234 int followed = follow_down(path); 235 if (!followed) 236 break; 237 res = 1; 238 } 239 return res; 240} 241 242static inline u32 autofs4_get_dev(struct autofs_sb_info *sbi) 243{ 244 return new_encode_dev(sbi->sb->s_dev); 245} 246 247static inline u64 autofs4_get_ino(struct autofs_sb_info *sbi) 248{ 249 return sbi->sb->s_root->d_inode->i_ino; 250} 251 252static inline int simple_positive(struct dentry *dentry) 253{ 254 return dentry->d_inode && !d_unhashed(dentry); 255} 256 257static inline int __simple_empty(struct dentry *dentry) 258{ 259 struct dentry *child; 260 int ret = 0; 261 262 list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child) 263 if (simple_positive(child)) 264 goto out; 265 ret = 1; 266out: 267 return ret; 268} 269 270static inline void autofs4_add_expiring(struct dentry *dentry) 271{ 272 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); 273 struct autofs_info *ino = autofs4_dentry_ino(dentry); 274 if (ino) { 275 spin_lock(&sbi->lookup_lock); 276 if (list_empty(&ino->expiring)) 277 list_add(&ino->expiring, &sbi->expiring_list); 278 spin_unlock(&sbi->lookup_lock); 279 } 280 return; 281} 282 283static inline void autofs4_del_expiring(struct dentry *dentry) 284{ 285 struct autofs_sb_info *sbi = autofs4_sbi(dentry->d_sb); 286 struct autofs_info *ino = autofs4_dentry_ino(dentry); 287 if (ino) { 288 spin_lock(&sbi->lookup_lock); 289 if (!list_empty(&ino->expiring)) 290 list_del_init(&ino->expiring); 291 spin_unlock(&sbi->lookup_lock); 292 } 293 return; 294} 295 296void autofs4_dentry_release(struct dentry *); 297extern void autofs4_kill_sb(struct super_block *); 298