linux/fs/proc/internal.h
Cyrill Gorcunov 818411616b fs, proc: introduce /proc/<pid>/task/<tid>/children entry
When we do checkpoint of a task we need to know the list of children the
task, has but there is no easy and fast way to generate reverse
parent->children chain from arbitrary <pid> (while a parent pid is
provided in "PPid" field of /proc/<pid>/status).

So instead of walking over all pids in the system (creating one big
process tree in memory, just to figure out which children a task has) --
we add explicit /proc/<pid>/task/<tid>/children entry, because the kernel
already has this kind of information but it is not yet exported.

This is a first level children, not the whole process tree.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31 17:49:32 -07:00

154 lines
5.1 KiB
C

/* internal.h: internal procfs definitions
*
* Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/proc_fs.h>
struct ctl_table_header;
extern struct proc_dir_entry proc_root;
#ifdef CONFIG_PROC_SYSCTL
extern int proc_sys_init(void);
extern void sysctl_head_put(struct ctl_table_header *head);
#else
static inline void proc_sys_init(void) { }
static inline void sysctl_head_put(struct ctl_table_header *head) { }
#endif
#ifdef CONFIG_NET
extern int proc_net_init(void);
#else
static inline int proc_net_init(void) { return 0; }
#endif
struct vmalloc_info {
unsigned long used;
unsigned long largest_chunk;
};
#ifdef CONFIG_MMU
#define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
extern void get_vmalloc_info(struct vmalloc_info *vmi);
#else
#define VMALLOC_TOTAL 0UL
#define get_vmalloc_info(vmi) \
do { \
(vmi)->used = 0; \
(vmi)->largest_chunk = 0; \
} while(0)
#endif
extern int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
struct pid *pid, struct task_struct *task);
extern int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
struct pid *pid, struct task_struct *task);
extern int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
struct pid *pid, struct task_struct *task);
extern int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
struct pid *pid, struct task_struct *task);
extern loff_t mem_lseek(struct file *file, loff_t offset, int orig);
extern const struct file_operations proc_tid_children_operations;
extern const struct file_operations proc_pid_maps_operations;
extern const struct file_operations proc_tid_maps_operations;
extern const struct file_operations proc_pid_numa_maps_operations;
extern const struct file_operations proc_tid_numa_maps_operations;
extern const struct file_operations proc_pid_smaps_operations;
extern const struct file_operations proc_tid_smaps_operations;
extern const struct file_operations proc_clear_refs_operations;
extern const struct file_operations proc_pagemap_operations;
extern const struct file_operations proc_net_operations;
extern const struct inode_operations proc_net_inode_operations;
struct proc_maps_private {
struct pid *pid;
struct task_struct *task;
#ifdef CONFIG_MMU
struct vm_area_struct *tail_vma;
#endif
};
void proc_init_inodecache(void);
static inline struct pid *proc_pid(struct inode *inode)
{
return PROC_I(inode)->pid;
}
static inline struct task_struct *get_proc_task(struct inode *inode)
{
return get_pid_task(proc_pid(inode), PIDTYPE_PID);
}
static inline int proc_fd(struct inode *inode)
{
return PROC_I(inode)->fd;
}
struct dentry *proc_lookup_de(struct proc_dir_entry *de, struct inode *ino,
struct dentry *dentry);
int proc_readdir_de(struct proc_dir_entry *de, struct file *filp, void *dirent,
filldir_t filldir);
struct pde_opener {
struct inode *inode;
struct file *file;
int (*release)(struct inode *, struct file *);
struct list_head lh;
};
void pde_users_dec(struct proc_dir_entry *pde);
extern spinlock_t proc_subdir_lock;
struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *);
int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir);
unsigned long task_vsize(struct mm_struct *);
unsigned long task_statm(struct mm_struct *,
unsigned long *, unsigned long *, unsigned long *, unsigned long *);
void task_mem(struct seq_file *, struct mm_struct *);
static inline struct proc_dir_entry *pde_get(struct proc_dir_entry *pde)
{
atomic_inc(&pde->count);
return pde;
}
void pde_put(struct proc_dir_entry *pde);
int proc_fill_super(struct super_block *);
struct inode *proc_get_inode(struct super_block *, struct proc_dir_entry *);
int proc_remount(struct super_block *sb, int *flags, char *data);
/*
* These are generic /proc routines that use the internal
* "struct proc_dir_entry" tree to traverse the filesystem.
*
* The /proc root directory has extended versions to take care
* of the /proc/<pid> subdirectories.
*/
int proc_readdir(struct file *, void *, filldir_t);
struct dentry *proc_lookup(struct inode *, struct dentry *, struct nameidata *);
/* Lookups */
typedef struct dentry *instantiate_t(struct inode *, struct dentry *,
struct task_struct *, const void *);
int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
const char *name, int len,
instantiate_t instantiate, struct task_struct *task, const void *ptr);
int pid_revalidate(struct dentry *dentry, struct nameidata *nd);
struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task);
extern const struct dentry_operations pid_dentry_operations;
int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat);
int proc_setattr(struct dentry *dentry, struct iattr *attr);
extern const struct inode_operations proc_ns_dir_inode_operations;
extern const struct file_operations proc_ns_dir_operations;