925d1c401f
The kernel implements readlink of /proc/pid/exe by getting the file from the first executable VMA. Then the path to the file is reconstructed and reported as the result. Because of the VMA walk the code is slightly different on nommu systems. This patch avoids separate /proc/pid/exe code on nommu systems. Instead of walking the VMAs to find the first executable file-backed VMA we store a reference to the exec'd file in the mm_struct. That reference would prevent the filesystem holding the executable file from being unmounted even after unmapping the VMAs. So we track the number of VM_EXECUTABLE VMAs and drop the new reference when the last one is unmapped. This avoids pinning the mounted filesystem. [akpm@linux-foundation.org: improve comments] [yamamoto@valinux.co.jp: fix dup_mmap] Signed-off-by: Matt Helsley <matthltc@us.ibm.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: David Howells <dhowells@redhat.com> Cc:"Eric W. Biederman" <ebiederm@xmission.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Hugh Dickins <hugh@veritas.com> Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
92 lines
2.8 KiB
C
92 lines
2.8 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>
|
|
|
|
#ifdef CONFIG_PROC_SYSCTL
|
|
extern int proc_sys_init(void);
|
|
#else
|
|
static inline void proc_sys_init(void) { }
|
|
#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;
|
|
};
|
|
|
|
extern struct mm_struct *mm_for_maps(struct task_struct *);
|
|
|
|
#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)
|
|
|
|
extern int nommu_vma_show(struct seq_file *, struct vm_area_struct *);
|
|
#endif
|
|
|
|
extern int maps_protect;
|
|
|
|
extern void create_seq_entry(char *name, mode_t mode,
|
|
const struct file_operations *f);
|
|
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_maps_operations;
|
|
extern const struct file_operations proc_numa_maps_operations;
|
|
extern const struct file_operations proc_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;
|
|
|
|
void free_proc_entry(struct proc_dir_entry *de);
|
|
|
|
int 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);
|