Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* -*- linux-c -*- ------------------------------------------------------- * |
| 2 | * |
| 3 | * linux/fs/autofs/autofs_i.h |
| 4 | * |
| 5 | * Copyright 1997-1998 Transmeta Corporation - All Rights Reserved |
| 6 | * |
| 7 | * This file is part of the Linux kernel and is made available under |
| 8 | * the terms of the GNU General Public License, version 2, or at your |
| 9 | * option, any later version, incorporated herein by reference. |
| 10 | * |
| 11 | * ----------------------------------------------------------------------- */ |
| 12 | |
| 13 | /* Internal header file for autofs */ |
| 14 | |
| 15 | #include <linux/auto_fs.h> |
| 16 | |
| 17 | /* This is the range of ioctl() numbers we claim as ours */ |
| 18 | #define AUTOFS_IOC_FIRST AUTOFS_IOC_READY |
| 19 | #define AUTOFS_IOC_COUNT 32 |
| 20 | |
| 21 | #include <linux/kernel.h> |
| 22 | #include <linux/slab.h> |
| 23 | #include <linux/time.h> |
| 24 | #include <linux/string.h> |
| 25 | #include <linux/wait.h> |
| 26 | #include <linux/dcache.h> |
| 27 | #include <linux/namei.h> |
| 28 | #include <linux/mount.h> |
| 29 | #include <linux/sched.h> |
| 30 | |
| 31 | #include <asm/current.h> |
| 32 | #include <asm/uaccess.h> |
| 33 | |
| 34 | #ifdef DEBUG |
| 35 | #define DPRINTK(D) (printk D) |
| 36 | #else |
| 37 | #define DPRINTK(D) ((void)0) |
| 38 | #endif |
| 39 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | /* |
| 41 | * If the daemon returns a negative response (AUTOFS_IOC_FAIL) then the |
| 42 | * kernel will keep the negative response cached for up to the time given |
| 43 | * here, although the time can be shorter if the kernel throws the dcache |
| 44 | * entry away. This probably should be settable from user space. |
| 45 | */ |
| 46 | #define AUTOFS_NEGATIVE_TIMEOUT (60*HZ) /* 1 minute */ |
| 47 | |
| 48 | /* Structures associated with the root directory hash table */ |
| 49 | |
| 50 | #define AUTOFS_HASH_SIZE 67 |
| 51 | |
| 52 | struct autofs_dir_ent { |
| 53 | int hash; |
| 54 | char *name; |
| 55 | int len; |
| 56 | ino_t ino; |
| 57 | struct dentry *dentry; |
| 58 | /* Linked list of entries */ |
| 59 | struct autofs_dir_ent *next; |
| 60 | struct autofs_dir_ent **back; |
| 61 | /* The following entries are for the expiry system */ |
| 62 | unsigned long last_usage; |
| 63 | struct list_head exp; |
| 64 | }; |
| 65 | |
| 66 | struct autofs_dirhash { |
| 67 | struct autofs_dir_ent *h[AUTOFS_HASH_SIZE]; |
| 68 | struct list_head expiry_head; |
| 69 | }; |
| 70 | |
| 71 | struct autofs_wait_queue { |
| 72 | wait_queue_head_t queue; |
| 73 | struct autofs_wait_queue *next; |
| 74 | autofs_wqt_t wait_queue_token; |
| 75 | /* We use the following to see what we are waiting for */ |
| 76 | int hash; |
| 77 | int len; |
| 78 | char *name; |
| 79 | /* This is for status reporting upon return */ |
| 80 | int status; |
| 81 | int wait_ctr; |
| 82 | }; |
| 83 | |
| 84 | struct autofs_symlink { |
| 85 | char *data; |
| 86 | int len; |
| 87 | time_t mtime; |
| 88 | }; |
| 89 | |
| 90 | #define AUTOFS_MAX_SYMLINKS 256 |
| 91 | |
| 92 | #define AUTOFS_ROOT_INO 1 |
| 93 | #define AUTOFS_FIRST_SYMLINK 2 |
| 94 | #define AUTOFS_FIRST_DIR_INO (AUTOFS_FIRST_SYMLINK+AUTOFS_MAX_SYMLINKS) |
| 95 | |
| 96 | #define AUTOFS_SYMLINK_BITMAP_LEN \ |
| 97 | ((AUTOFS_MAX_SYMLINKS+((sizeof(long)*1)-1))/(sizeof(long)*8)) |
| 98 | |
| 99 | #define AUTOFS_SBI_MAGIC 0x6d4a556d |
| 100 | |
| 101 | struct autofs_sb_info { |
| 102 | u32 magic; |
| 103 | struct file *pipe; |
| 104 | pid_t oz_pgrp; |
| 105 | int catatonic; |
Alexander Krizhanovsky | f76baf9 | 2005-09-09 13:01:59 -0700 | [diff] [blame] | 106 | struct super_block *sb; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | unsigned long exp_timeout; |
| 108 | ino_t next_dir_ino; |
| 109 | struct autofs_wait_queue *queues; /* Wait queue pointer */ |
| 110 | struct autofs_dirhash dirhash; /* Root directory hash */ |
| 111 | struct autofs_symlink symlink[AUTOFS_MAX_SYMLINKS]; |
| 112 | unsigned long symlink_bitmap[AUTOFS_SYMLINK_BITMAP_LEN]; |
| 113 | }; |
| 114 | |
| 115 | static inline struct autofs_sb_info *autofs_sbi(struct super_block *sb) |
| 116 | { |
| 117 | return (struct autofs_sb_info *)(sb->s_fs_info); |
| 118 | } |
| 119 | |
| 120 | /* autofs_oz_mode(): do we see the man behind the curtain? (The |
| 121 | processes which do manipulations for us in user space sees the raw |
| 122 | filesystem without "magic".) */ |
| 123 | |
| 124 | static inline int autofs_oz_mode(struct autofs_sb_info *sbi) { |
| 125 | return sbi->catatonic || process_group(current) == sbi->oz_pgrp; |
| 126 | } |
| 127 | |
| 128 | /* Hash operations */ |
| 129 | |
| 130 | void autofs_initialize_hash(struct autofs_dirhash *); |
| 131 | struct autofs_dir_ent *autofs_hash_lookup(const struct autofs_dirhash *,struct qstr *); |
| 132 | void autofs_hash_insert(struct autofs_dirhash *,struct autofs_dir_ent *); |
| 133 | void autofs_hash_delete(struct autofs_dir_ent *); |
| 134 | struct autofs_dir_ent *autofs_hash_enum(const struct autofs_dirhash *,off_t *,struct autofs_dir_ent *); |
| 135 | void autofs_hash_dputall(struct autofs_dirhash *); |
Alexander Krizhanovsky | f76baf9 | 2005-09-09 13:01:59 -0700 | [diff] [blame] | 136 | void autofs_hash_nuke(struct autofs_sb_info *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 137 | |
| 138 | /* Expiration-handling functions */ |
| 139 | |
| 140 | void autofs_update_usage(struct autofs_dirhash *,struct autofs_dir_ent *); |
| 141 | struct autofs_dir_ent *autofs_expire(struct super_block *,struct autofs_sb_info *, struct vfsmount *mnt); |
| 142 | |
| 143 | /* Operations structures */ |
| 144 | |
| 145 | extern struct inode_operations autofs_root_inode_operations; |
| 146 | extern struct inode_operations autofs_symlink_inode_operations; |
Arjan van de Ven | 4b6f5d2 | 2006-03-28 01:56:42 -0800 | [diff] [blame] | 147 | extern const struct file_operations autofs_root_operations; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 148 | |
| 149 | /* Initializing function */ |
| 150 | |
| 151 | int autofs_fill_super(struct super_block *, void *, int); |
David Howells | 0e7d738 | 2006-10-19 23:28:36 -0700 | [diff] [blame] | 152 | void autofs_kill_sb(struct super_block *sb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 153 | |
| 154 | /* Queue management functions */ |
| 155 | |
| 156 | int autofs_wait(struct autofs_sb_info *,struct qstr *); |
| 157 | int autofs_wait_release(struct autofs_sb_info *,autofs_wqt_t,int); |
| 158 | void autofs_catatonic_mode(struct autofs_sb_info *); |
| 159 | |
| 160 | #ifdef DEBUG |
| 161 | void autofs_say(const char *name, int len); |
| 162 | #else |
| 163 | #define autofs_say(n,l) ((void)0) |
| 164 | #endif |