xref: /openbmc/linux/fs/proc/nommu.c (revision 1da177e4)
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 list of all the VMAs the kernel knows about
37  * - nommu kernals have a single flat list
38  */
39 static int nommu_vma_list_show(struct seq_file *m, void *v)
40 {
41 	struct vm_area_struct *vma;
42 	unsigned long ino = 0;
43 	struct file *file;
44 	dev_t dev = 0;
45 	int flags, len;
46 
47 	vma = rb_entry((struct rb_node *) v, struct vm_area_struct, vm_rb);
48 
49 	flags = vma->vm_flags;
50 	file = vma->vm_file;
51 
52 	if (file) {
53 		struct inode *inode = vma->vm_file->f_dentry->d_inode;
54 		dev = inode->i_sb->s_dev;
55 		ino = inode->i_ino;
56 	}
57 
58 	seq_printf(m,
59 		   "%08lx-%08lx %c%c%c%c %08lx %02x:%02x %lu %n",
60 		   vma->vm_start,
61 		   vma->vm_end,
62 		   flags & VM_READ ? 'r' : '-',
63 		   flags & VM_WRITE ? 'w' : '-',
64 		   flags & VM_EXEC ? 'x' : '-',
65 		   flags & VM_MAYSHARE ? flags & VM_SHARED ? 'S' : 's' : 'p',
66 		   vma->vm_pgoff << PAGE_SHIFT,
67 		   MAJOR(dev), MINOR(dev), ino, &len);
68 
69 	if (file) {
70 		len = 25 + sizeof(void *) * 6 - len;
71 		if (len < 1)
72 			len = 1;
73 		seq_printf(m, "%*c", len, ' ');
74 		seq_path(m, file->f_vfsmnt, file->f_dentry, "");
75 	}
76 
77 	seq_putc(m, '\n');
78 	return 0;
79 }
80 
81 static void *nommu_vma_list_start(struct seq_file *m, loff_t *_pos)
82 {
83 	struct rb_node *_rb;
84 	loff_t pos = *_pos;
85 	void *next = NULL;
86 
87 	down_read(&nommu_vma_sem);
88 
89 	for (_rb = rb_first(&nommu_vma_tree); _rb; _rb = rb_next(_rb)) {
90 		if (pos == 0) {
91 			next = _rb;
92 			break;
93 		}
94 	}
95 
96 	return next;
97 }
98 
99 static void nommu_vma_list_stop(struct seq_file *m, void *v)
100 {
101 	up_read(&nommu_vma_sem);
102 }
103 
104 static void *nommu_vma_list_next(struct seq_file *m, void *v, loff_t *pos)
105 {
106 	(*pos)++;
107 	return rb_next((struct rb_node *) v);
108 }
109 
110 static struct seq_operations proc_nommu_vma_list_seqop = {
111 	.start	= nommu_vma_list_start,
112 	.next	= nommu_vma_list_next,
113 	.stop	= nommu_vma_list_stop,
114 	.show	= nommu_vma_list_show
115 };
116 
117 static int proc_nommu_vma_list_open(struct inode *inode, struct file *file)
118 {
119 	return seq_open(file, &proc_nommu_vma_list_seqop);
120 }
121 
122 static struct file_operations proc_nommu_vma_list_operations = {
123 	.open    = proc_nommu_vma_list_open,
124 	.read    = seq_read,
125 	.llseek  = seq_lseek,
126 	.release = seq_release,
127 };
128 
129 static int __init proc_nommu_init(void)
130 {
131 	create_seq_entry("maps", S_IRUGO, &proc_nommu_vma_list_operations);
132 	return 0;
133 }
134 
135 module_init(proc_nommu_init);
136