1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* nommu.c: mmu-less memory info files
4 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
8 #include <linux/init.h>
9 #include <linux/module.h>
10 #include <linux/errno.h>
11 #include <linux/time.h>
12 #include <linux/kernel.h>
13 #include <linux/string.h>
14 #include <linux/mman.h>
15 #include <linux/proc_fs.h>
17 #include <linux/mmzone.h>
18 #include <linux/pagemap.h>
19 #include <linux/swap.h>
20 #include <linux/smp.h>
21 #include <linux/seq_file.h>
22 #include <linux/hugetlb.h>
23 #include <linux/vmalloc.h>
24 #include <linux/uaccess.h>
26 #include <asm/div64.h>
30 * display a single region to a sequenced file
32 static int nommu_region_show(struct seq_file *m, struct vm_region *region)
34 unsigned long ino = 0;
39 flags = region->vm_flags;
40 file = region->vm_file;
43 struct inode *inode = file_inode(region->vm_file);
44 dev = inode->i_sb->s_dev;
48 seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
50 "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ",
53 flags & VM_READ ? 'r' : '-',
54 flags & VM_WRITE ? 'w' : '-',
55 flags & VM_EXEC ? 'x' : '-',
56 flags & VM_MAYSHARE ? flags & VM_SHARED ? 'S' : 's' : 'p',
57 ((loff_t)region->vm_pgoff) << PAGE_SHIFT,
58 MAJOR(dev), MINOR(dev), ino);
62 seq_file_path(m, file, "");
70 * display a list of all the REGIONs the kernel knows about
71 * - nommu kernels have a single flat list
73 static int nommu_region_list_show(struct seq_file *m, void *_p)
75 struct rb_node *p = _p;
77 return nommu_region_show(m, rb_entry(p, struct vm_region, vm_rb));
80 static void *nommu_region_list_start(struct seq_file *m, loff_t *_pos)
85 down_read(&nommu_region_sem);
87 for (p = rb_first(&nommu_region_tree); p; p = rb_next(p))
93 static void nommu_region_list_stop(struct seq_file *m, void *v)
95 up_read(&nommu_region_sem);
98 static void *nommu_region_list_next(struct seq_file *m, void *v, loff_t *pos)
101 return rb_next((struct rb_node *) v);
104 static const struct seq_operations proc_nommu_region_list_seqop = {
105 .start = nommu_region_list_start,
106 .next = nommu_region_list_next,
107 .stop = nommu_region_list_stop,
108 .show = nommu_region_list_show
111 static int __init proc_nommu_init(void)
113 proc_create_seq("maps", S_IRUGO, NULL, &proc_nommu_region_list_seqop);
117 fs_initcall(proc_nommu_init);