kernel-ark/fs/autofs/autofs_i.h
Sukadev Bhattiprolu fa0334f19f Replace pid_t in autofs with struct pid reference
Make autofs container-friendly by caching struct pid reference rather than
pid_t and using pid_nr() to retreive a task's pid_t.

ChangeLog:
	- Fix Eric Biederman's comments - Use find_get_pid() to hold a
	  reference to oz_pgrp and release while unmounting; separate out
	  changes to autofs and autofs4.
	- Fix Cedric's comments: retain old prototype of parse_options()
	  and move necessary change to its caller.

Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: containers@lists.osdl.org
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-11 08:29:36 -07:00

165 lines
4.6 KiB
C

/* -*- linux-c -*- ------------------------------------------------------- *
*
* linux/fs/autofs/autofs_i.h
*
* Copyright 1997-1998 Transmeta Corporation - All Rights Reserved
*
* 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>
/* This is the range of ioctl() numbers we claim as ours */
#define AUTOFS_IOC_FIRST AUTOFS_IOC_READY
#define AUTOFS_IOC_COUNT 32
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/string.h>
#include <linux/wait.h>
#include <linux/dcache.h>
#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/sched.h>
#include <asm/current.h>
#include <asm/uaccess.h>
#ifdef DEBUG
#define DPRINTK(D) (printk D)
#else
#define DPRINTK(D) ((void)0)
#endif
/*
* If the daemon returns a negative response (AUTOFS_IOC_FAIL) then the
* kernel will keep the negative response cached for up to the time given
* here, although the time can be shorter if the kernel throws the dcache
* entry away. This probably should be settable from user space.
*/
#define AUTOFS_NEGATIVE_TIMEOUT (60*HZ) /* 1 minute */
/* Structures associated with the root directory hash table */
#define AUTOFS_HASH_SIZE 67
struct autofs_dir_ent {
int hash;
char *name;
int len;
ino_t ino;
struct dentry *dentry;
/* Linked list of entries */
struct autofs_dir_ent *next;
struct autofs_dir_ent **back;
/* The following entries are for the expiry system */
unsigned long last_usage;
struct list_head exp;
};
struct autofs_dirhash {
struct autofs_dir_ent *h[AUTOFS_HASH_SIZE];
struct list_head expiry_head;
};
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 */
int hash;
int len;
char *name;
/* This is for status reporting upon return */
int status;
int wait_ctr;
};
struct autofs_symlink {
char *data;
int len;
time_t mtime;
};
#define AUTOFS_MAX_SYMLINKS 256
#define AUTOFS_ROOT_INO 1
#define AUTOFS_FIRST_SYMLINK 2
#define AUTOFS_FIRST_DIR_INO (AUTOFS_FIRST_SYMLINK+AUTOFS_MAX_SYMLINKS)
#define AUTOFS_SYMLINK_BITMAP_LEN \
((AUTOFS_MAX_SYMLINKS+((sizeof(long)*1)-1))/(sizeof(long)*8))
#define AUTOFS_SBI_MAGIC 0x6d4a556d
struct autofs_sb_info {
u32 magic;
struct file *pipe;
struct pid *oz_pgrp;
int catatonic;
struct super_block *sb;
unsigned long exp_timeout;
ino_t next_dir_ino;
struct autofs_wait_queue *queues; /* Wait queue pointer */
struct autofs_dirhash dirhash; /* Root directory hash */
struct autofs_symlink symlink[AUTOFS_MAX_SYMLINKS];
unsigned long symlink_bitmap[AUTOFS_SYMLINK_BITMAP_LEN];
};
static inline struct autofs_sb_info *autofs_sbi(struct super_block *sb)
{
return (struct autofs_sb_info *)(sb->s_fs_info);
}
/* 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;
}
/* Hash operations */
void autofs_initialize_hash(struct autofs_dirhash *);
struct autofs_dir_ent *autofs_hash_lookup(const struct autofs_dirhash *,struct qstr *);
void autofs_hash_insert(struct autofs_dirhash *,struct autofs_dir_ent *);
void autofs_hash_delete(struct autofs_dir_ent *);
struct autofs_dir_ent *autofs_hash_enum(const struct autofs_dirhash *,off_t *,struct autofs_dir_ent *);
void autofs_hash_dputall(struct autofs_dirhash *);
void autofs_hash_nuke(struct autofs_sb_info *);
/* Expiration-handling functions */
void autofs_update_usage(struct autofs_dirhash *,struct autofs_dir_ent *);
struct autofs_dir_ent *autofs_expire(struct super_block *,struct autofs_sb_info *, struct vfsmount *mnt);
/* Operations structures */
extern const struct inode_operations autofs_root_inode_operations;
extern const struct inode_operations autofs_symlink_inode_operations;
extern const struct file_operations autofs_root_operations;
/* Initializing function */
int autofs_fill_super(struct super_block *, void *, int);
void autofs_kill_sb(struct super_block *sb);
/* Queue management functions */
int autofs_wait(struct autofs_sb_info *,struct qstr *);
int autofs_wait_release(struct autofs_sb_info *,autofs_wqt_t,int);
void autofs_catatonic_mode(struct autofs_sb_info *);
#ifdef DEBUG
void autofs_say(const char *name, int len);
#else
#define autofs_say(n,l) ((void)0)
#endif