diff options
Diffstat (limited to 'fs/autofs/autofs_i.h')
| -rw-r--r-- | fs/autofs/autofs_i.h | 273 |
1 files changed, 273 insertions, 0 deletions
diff --git a/fs/autofs/autofs_i.h b/fs/autofs/autofs_i.h new file mode 100644 index 000000000000..9110b66c7ef1 --- /dev/null +++ b/fs/autofs/autofs_i.h @@ -0,0 +1,273 @@ +/* + * Copyright 1997-1998 Transmeta Corporation - All Rights Reserved + * Copyright 2005-2006 Ian Kent <raven@themaw.net> + * + * This file is part of the Linux kernel and is made available under + * the terms of the GNU General Public License, version 2, or at your + * option, any later version, incorporated herein by reference. + */ + +/* Internal header file for autofs */ + +#include <linux/auto_fs.h> +#include <linux/auto_dev-ioctl.h> + +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/time.h> +#include <linux/string.h> +#include <linux/wait.h> +#include <linux/sched.h> +#include <linux/mount.h> +#include <linux/namei.h> +#include <linux/uaccess.h> +#include <linux/mutex.h> +#include <linux/spinlock.h> +#include <linux/list.h> +#include <linux/completion.h> +#include <asm/current.h> + +/* This is the range of ioctl() numbers we claim as ours */ +#define AUTOFS_IOC_FIRST AUTOFS_IOC_READY +#define AUTOFS_IOC_COUNT 32 + +#define AUTOFS_DEV_IOCTL_IOC_FIRST (AUTOFS_DEV_IOCTL_VERSION) +#define AUTOFS_DEV_IOCTL_IOC_COUNT \ + (AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD - AUTOFS_DEV_IOCTL_VERSION_CMD) + +#ifdef pr_fmt +#undef pr_fmt +#endif +#define pr_fmt(fmt) KBUILD_MODNAME ":pid:%d:%s: " fmt, current->pid, __func__ + +/* + * Unified info structure. This is pointed to by both the dentry and + * inode structures. Each file in the filesystem has an instance of this + * structure. It holds a reference to the dentry, so dentries are never + * flushed while the file exists. All name lookups are dealt with at the + * dentry level, although the filesystem can interfere in the validation + * process. Readdir is implemented by traversing the dentry lists. + */ +struct autofs_info { + struct dentry *dentry; + struct inode *inode; + + int flags; + + struct completion expire_complete; + + struct list_head active; + int active_count; + + struct list_head expiring; + + struct autofs_sb_info *sbi; + unsigned long last_used; + atomic_t count; + + kuid_t uid; + kgid_t gid; +}; + +#define AUTOFS_INF_EXPIRING (1<<0) /* dentry in the process of expiring */ +#define AUTOFS_INF_WANT_EXPIRE (1<<1) /* the dentry is being considered + * for expiry, so RCU_walk is + * not permitted. If it progresses to + * actual expiry attempt, the flag is + * not cleared when EXPIRING is set - + * in that case it gets cleared only + * when it comes to clearing EXPIRING. + */ +#define AUTOFS_INF_PENDING (1<<2) /* dentry pending mount */ + +struct autofs_wait_queue { + wait_queue_head_t queue; + struct autofs_wait_queue *next; + autofs_wqt_t wait_queue_token; + /* We use the following to see what we are waiting for */ + struct qstr name; + u32 dev; + u64 ino; + kuid_t uid; + kgid_t gid; + pid_t pid; + pid_t tgid; + /* This is for status reporting upon return */ + int status; + unsigned int wait_ctr; +}; + +#define AUTOFS_SBI_MAGIC 0x6d4a556d + +struct autofs_sb_info { + u32 magic; + int pipefd; + struct file *pipe; + struct pid *oz_pgrp; + int catatonic; + int version; + int sub_version; + int min_proto; + int max_proto; + unsigned long exp_timeout; + unsigned int type; + struct super_block *sb; + struct mutex wq_mutex; + struct mutex pipe_mutex; + spinlock_t fs_lock; + struct autofs_wait_queue *queues; /* Wait queue pointer */ + spinlock_t lookup_lock; + struct list_head active_list; + struct list_head expiring_list; + struct rcu_head rcu; +}; + +static inline struct autofs_sb_info *autofs_sbi(struct super_block *sb) +{ + return (struct autofs_sb_info *)(sb->s_fs_info); +} + +static inline struct autofs_info *autofs_dentry_ino(struct dentry *dentry) +{ + return (struct autofs_info *)(dentry->d_fsdata); +} + +/* autofs_oz_mode(): do we see the man behind the curtain? (The + * processes which do manipulations for us in user space sees the raw + * filesystem without "magic".) + */ +static inline int autofs_oz_mode(struct autofs_sb_info *sbi) +{ + return sbi->catatonic || task_pgrp(current) == sbi->oz_pgrp; +} + +struct inode *autofs_get_inode(struct super_block *, umode_t); +void autofs_free_ino(struct autofs_info *); + +/* Expiration */ +int is_autofs_dentry(struct dentry *); +int autofs_expire_wait(const struct path *path, int rcu_walk); +int autofs_expire_run(struct super_block *, struct vfsmount *, + struct autofs_sb_info *, + struct autofs_packet_expire __user *); +int autofs_do_expire_multi(struct super_block *sb, struct vfsmount *mnt, + struct autofs_sb_info *sbi, int when); +int autofs_expire_multi(struct super_block *, struct vfsmount *, + struct autofs_sb_info *, int __user *); +struct dentry *autofs_expire_direct(struct super_block *sb, + struct vfsmount *mnt, + struct autofs_sb_info *sbi, int how); +struct dentry *autofs_expire_indirect(struct super_block *sb, + struct vfsmount *mnt, + struct autofs_sb_info *sbi, int how); + +/* Device node initialization */ + +int autofs_dev_ioctl_init(void); +void autofs_dev_ioctl_exit(void); + +/* Operations structures */ + +extern const struct inode_operations autofs_symlink_inode_operations; +extern const struct inode_operations autofs_dir_inode_operations; +extern const struct file_operations autofs_dir_operations; +extern const struct file_operations autofs_root_operations; +extern const struct dentry_operations autofs_dentry_operations; + +/* VFS automount flags management functions */ +static inline void __managed_dentry_set_managed(struct dentry *dentry) +{ + dentry->d_flags |= (DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT); +} + +static inline void managed_dentry_set_managed(struct dentry *dentry) +{ + spin_lock(&dentry->d_lock); + __managed_dentry_set_managed(dentry); + spin_unlock(&dentry->d_lock); +} + +static inline void __managed_dentry_clear_managed(struct dentry *dentry) +{ + dentry->d_flags &= ~(DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT); +} + +static inline void managed_dentry_clear_managed(struct dentry *dentry) +{ + spin_lock(&dentry->d_lock); + __managed_dentry_clear_managed(dentry); + spin_unlock(&dentry->d_lock); +} + +/* Initializing function */ + +int autofs_fill_super(struct super_block *, void *, int); +struct autofs_info *autofs_new_ino(struct autofs_sb_info *); +void autofs_clean_ino(struct autofs_info *); + +static inline int autofs_prepare_pipe(struct file *pipe) +{ + if (!(pipe->f_mode & FMODE_CAN_WRITE)) + return -EINVAL; + if (!S_ISFIFO(file_inode(pipe)->i_mode)) + return -EINVAL; + /* We want a packet pipe */ + pipe->f_flags |= O_DIRECT; + return 0; +} + +/* Queue management functions */ + +int autofs_wait(struct autofs_sb_info *, + const struct path *, enum autofs_notify); +int autofs_wait_release(struct autofs_sb_info *, autofs_wqt_t, int); +void autofs_catatonic_mode(struct autofs_sb_info *); + +static inline u32 autofs_get_dev(struct autofs_sb_info *sbi) +{ + return new_encode_dev(sbi->sb->s_dev); +} + +static inline u64 autofs_get_ino(struct autofs_sb_info *sbi) +{ + return d_inode(sbi->sb->s_root)->i_ino; +} + +static inline void __autofs_add_expiring(struct dentry *dentry) +{ + struct autofs_sb_info *sbi = autofs_sbi(dentry->d_sb); + struct autofs_info *ino = autofs_dentry_ino(dentry); + + if (ino) { + if (list_empty(&ino->expiring)) + list_add(&ino->expiring, &sbi->expiring_list); + } +} + +static inline void autofs_add_expiring(struct dentry *dentry) +{ + struct autofs_sb_info *sbi = autofs_sbi(dentry->d_sb); + struct autofs_info *ino = autofs_dentry_ino(dentry); + + if (ino) { + spin_lock(&sbi->lookup_lock); + if (list_empty(&ino->expiring)) + list_add(&ino->expiring, &sbi->expiring_list); + spin_unlock(&sbi->lookup_lock); + } +} + +static inline void autofs_del_expiring(struct dentry *dentry) +{ + struct autofs_sb_info *sbi = autofs_sbi(dentry->d_sb); + struct autofs_info *ino = autofs_dentry_ino(dentry); + + if (ino) { + spin_lock(&sbi->lookup_lock); + if (!list_empty(&ino->expiring)) + list_del_init(&ino->expiring); + spin_unlock(&sbi->lookup_lock); + } +} + +void autofs_kill_sb(struct super_block *); |