1/* nommu.c: mmu-less memory info files
2 *
3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#include <linux/init.h>
13#include <linux/module.h>
14#include <linux/errno.h>
15#include <linux/time.h>
16#include <linux/kernel.h>
17#include <linux/string.h>
18#include <linux/mman.h>
19#include <linux/proc_fs.h>
20#include <linux/mm.h>
21#include <linux/mmzone.h>
22#include <linux/pagemap.h>
23#include <linux/swap.h>
24#include <linux/slab.h>
25#include <linux/smp.h>
26#include <linux/seq_file.h>
27#include <linux/hugetlb.h>
28#include <linux/vmalloc.h>
29#include <asm/uaccess.h>
30#include <asm/pgtable.h>
31#include <asm/tlb.h>
32#include <asm/div64.h>
33#include "internal.h"
34
35/*
36 * display a single VMA to a sequenced file
37 */
38int nommu_vma_show(struct seq_file *m, struct vm_area_struct *vma)
39{
40	unsigned long ino = 0;
41	struct file *file;
42	dev_t dev = 0;
43	int flags, len;
44
45	flags = vma->vm_flags;
46	file = vma->vm_file;
47
48	if (file) {
49		struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
50		dev = inode->i_sb->s_dev;
51		ino = inode->i_ino;
52	}
53
54	seq_printf(m,
55		   "%08lx-%08lx %c%c%c%c %08lx %02x:%02x %lu %n",
56		   vma->vm_start,
57		   vma->vm_end,
58		   flags & VM_READ ? 'r' : '-',
59		   flags & VM_WRITE ? 'w' : '-',
60		   flags & VM_EXEC ? 'x' : '-',
61		   flags & VM_MAYSHARE ? flags & VM_SHARED ? 'S' : 's' : 'p',
62		   vma->vm_pgoff << PAGE_SHIFT,
63		   MAJOR(dev), MINOR(dev), ino, &len);
64
65	if (file) {
66		len = 25 + sizeof(void *) * 6 - len;
67		if (len < 1)
68			len = 1;
69		seq_printf(m, "%*c", len, ' ');
70		seq_path(m, file->f_path.mnt, file->f_path.dentry, "");
71	}
72
73	seq_putc(m, '\n');
74	return 0;
75}
76
77/*
78 * display a list of all the VMAs the kernel knows about
79 * - nommu kernals have a single flat list
80 */
81static int nommu_vma_list_show(struct seq_file *m, void *v)
82{
83	struct vm_area_struct *vma;
84
85	vma = rb_entry((struct rb_node *) v, struct vm_area_struct, vm_rb);
86	return nommu_vma_show(m, vma);
87}
88
89static void *nommu_vma_list_start(struct seq_file *m, loff_t *_pos)
90{
91	struct rb_node *_rb;
92	loff_t pos = *_pos;
93	void *next = NULL;
94
95	down_read(&nommu_vma_sem);
96
97	for (_rb = rb_first(&nommu_vma_tree); _rb; _rb = rb_next(_rb)) {
98		if (pos == 0) {
99			next = _rb;
100			break;
101		}
102		pos--;
103	}
104
105	return next;
106}
107
108static void nommu_vma_list_stop(struct seq_file *m, void *v)
109{
110	up_read(&nommu_vma_sem);
111}
112
113static void *nommu_vma_list_next(struct seq_file *m, void *v, loff_t *pos)
114{
115	(*pos)++;
116	return rb_next((struct rb_node *) v);
117}
118
119static struct seq_operations proc_nommu_vma_list_seqop = {
120	.start	= nommu_vma_list_start,
121	.next	= nommu_vma_list_next,
122	.stop	= nommu_vma_list_stop,
123	.show	= nommu_vma_list_show
124};
125
126static int proc_nommu_vma_list_open(struct inode *inode, struct file *file)
127{
128	return seq_open(file, &proc_nommu_vma_list_seqop);
129}
130
131static const struct file_operations proc_nommu_vma_list_operations = {
132	.open    = proc_nommu_vma_list_open,
133	.read    = seq_read,
134	.llseek  = seq_lseek,
135	.release = seq_release,
136};
137
138static int __init proc_nommu_init(void)
139{
140	create_seq_entry("maps", S_IRUGO, &proc_nommu_vma_list_operations);
141	return 0;
142}
143
144module_init(proc_nommu_init);
145