1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* nommu.c: mmu-less memory info files |
3 | * |
4 | * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. |
5 | * Written by David Howells (dhowells@redhat.com) |
6 | */ |
7 | |
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> |
16 | #include <linux/mm.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 <asm/tlb.h> |
25 | #include <asm/div64.h> |
26 | #include "internal.h" |
27 | |
28 | /* |
29 | * display a single region to a sequenced file |
30 | */ |
31 | static int nommu_region_show(struct seq_file *m, struct vm_region *region) |
32 | { |
33 | unsigned long ino = 0; |
34 | struct file *file; |
35 | dev_t dev = 0; |
36 | int flags; |
37 | |
38 | flags = region->vm_flags; |
39 | file = region->vm_file; |
40 | |
41 | if (file) { |
42 | struct inode *inode = file_inode(f: region->vm_file); |
43 | dev = inode->i_sb->s_dev; |
44 | ino = inode->i_ino; |
45 | } |
46 | |
47 | seq_setwidth(m, size: 25 + sizeof(void *) * 6 - 1); |
48 | seq_printf(m, |
49 | fmt: "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu " , |
50 | region->vm_start, |
51 | region->vm_end, |
52 | flags & VM_READ ? 'r' : '-', |
53 | flags & VM_WRITE ? 'w' : '-', |
54 | flags & VM_EXEC ? 'x' : '-', |
55 | flags & VM_MAYSHARE ? flags & VM_SHARED ? 'S' : 's' : 'p', |
56 | ((loff_t)region->vm_pgoff) << PAGE_SHIFT, |
57 | MAJOR(dev), MINOR(dev), ino); |
58 | |
59 | if (file) { |
60 | seq_pad(m, c: ' '); |
61 | seq_path(m, file_user_path(f: file), "" ); |
62 | } |
63 | |
64 | seq_putc(m, c: '\n'); |
65 | return 0; |
66 | } |
67 | |
68 | /* |
69 | * display a list of all the REGIONs the kernel knows about |
70 | * - nommu kernels have a single flat list |
71 | */ |
72 | static int nommu_region_list_show(struct seq_file *m, void *_p) |
73 | { |
74 | struct rb_node *p = _p; |
75 | |
76 | return nommu_region_show(m, rb_entry(p, struct vm_region, vm_rb)); |
77 | } |
78 | |
79 | static void *nommu_region_list_start(struct seq_file *m, loff_t *_pos) |
80 | { |
81 | struct rb_node *p; |
82 | loff_t pos = *_pos; |
83 | |
84 | down_read(sem: &nommu_region_sem); |
85 | |
86 | for (p = rb_first(&nommu_region_tree); p; p = rb_next(p)) |
87 | if (pos-- == 0) |
88 | return p; |
89 | return NULL; |
90 | } |
91 | |
92 | static void nommu_region_list_stop(struct seq_file *m, void *v) |
93 | { |
94 | up_read(sem: &nommu_region_sem); |
95 | } |
96 | |
97 | static void *nommu_region_list_next(struct seq_file *m, void *v, loff_t *pos) |
98 | { |
99 | (*pos)++; |
100 | return rb_next((struct rb_node *) v); |
101 | } |
102 | |
103 | static const struct seq_operations proc_nommu_region_list_seqop = { |
104 | .start = nommu_region_list_start, |
105 | .next = nommu_region_list_next, |
106 | .stop = nommu_region_list_stop, |
107 | .show = nommu_region_list_show |
108 | }; |
109 | |
110 | static int __init proc_nommu_init(void) |
111 | { |
112 | proc_create_seq("maps" , S_IRUGO, NULL, &proc_nommu_region_list_seqop); |
113 | return 0; |
114 | } |
115 | |
116 | fs_initcall(proc_nommu_init); |
117 | |