projects/linux·blob v6.1 · refs

146 lines · 3.4 KiB

1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Module proc support
4 *
5 * Copyright (C) 2008 Alexey Dobriyan
6 */
7
8#include <linux/module.h>
9#include <linux/kallsyms.h>
10#include <linux/mutex.h>
11#include <linux/seq_file.h>
12#include <linux/proc_fs.h>
13#include "internal.h"
14
15#ifdef CONFIG_MODULE_UNLOAD
16static inline void print_unload_info(struct seq_file *m, struct module *mod)
17{
18 struct module_use *use;
19 int printed_something = 0;
20
21 seq_printf(m, " %i ", module_refcount(mod));
22
23 /*
24 * Always include a trailing , so userspace can differentiate
25 * between this and the old multi-field proc format.
26 */
27 list_for_each_entry(use, &mod->source_list, source_list) {
28 printed_something = 1;
29 seq_printf(m, "%s,", use->source->name);
30 }
31
32 if (mod->init && !mod->exit) {
33 printed_something = 1;
34 seq_puts(m, "[permanent],");
35 }
36
37 if (!printed_something)
38 seq_puts(m, "-");
39}
40#else /* !CONFIG_MODULE_UNLOAD */
41static inline void print_unload_info(struct seq_file *m, struct module *mod)
42{
43 /* We don't know the usage count, or what modules are using. */
44 seq_puts(m, " - -");
45}
46#endif /* CONFIG_MODULE_UNLOAD */
47
48/* Called by the /proc file system to return a list of modules. */
49static void *m_start(struct seq_file *m, loff_t *pos)
50{
51 mutex_lock(&module_mutex);
52 return seq_list_start(&modules, *pos);
53}
54
55static void *m_next(struct seq_file *m, void *p, loff_t *pos)
56{
57 return seq_list_next(p, &modules, pos);
58}
59
60static void m_stop(struct seq_file *m, void *p)
61{
62 mutex_unlock(&module_mutex);
63}
64
65static int m_show(struct seq_file *m, void *p)
66{
67 struct module *mod = list_entry(p, struct module, list);
68 char buf[MODULE_FLAGS_BUF_SIZE];
69 void *value;
70 unsigned int size;
71
72 /* We always ignore unformed modules. */
73 if (mod->state == MODULE_STATE_UNFORMED)
74 return 0;
75
76 size = mod->init_layout.size + mod->core_layout.size;
77#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC
78 size += mod->data_layout.size;
79#endif
80 seq_printf(m, "%s %u", mod->name, size);
81 print_unload_info(m, mod);
82
83 /* Informative for users. */
84 seq_printf(m, " %s",
85 mod->state == MODULE_STATE_GOING ? "Unloading" :
86 mod->state == MODULE_STATE_COMING ? "Loading" :
87 "Live");
88 /* Used by oprofile and other similar tools. */
89 value = m->private ? NULL : mod->core_layout.base;
90 seq_printf(m, " 0x%px", value);
91
92 /* Taints info */
93 if (mod->taints)
94 seq_printf(m, " %s", module_flags(mod, buf, true));
95
96 seq_puts(m, "\n");
97 return 0;
98}
99
100/*
101 * Format: modulename size refcount deps address
102 *
103 * Where refcount is a number or -, and deps is a comma-separated list
104 * of depends or -.
105 */
106static const struct seq_operations modules_op = {
107 .start = m_start,
108 .next = m_next,
109 .stop = m_stop,
110 .show = m_show
111};
112
113/*
114 * This also sets the "private" pointer to non-NULL if the
115 * kernel pointers should be hidden (so you can just test
116 * "m->private" to see if you should keep the values private).
117 *
118 * We use the same logic as for /proc/kallsyms.
119 */
120static int modules_open(struct inode *inode, struct file *file)
121{
122 int err = seq_open(file, &modules_op);
123
124 if (!err) {
125 struct seq_file *m = file->private_data;
126
127 m->private = kallsyms_show_value(file->f_cred) ? NULL : (void *)8ul;
128 }
129
130 return err;
131}
132
133static const struct proc_ops modules_proc_ops = {
134 .proc_flags = PROC_ENTRY_PERMANENT,
135 .proc_open = modules_open,
136 .proc_read = seq_read,
137 .proc_lseek = seq_lseek,
138 .proc_release = seq_release,
139};
140
141static int __init proc_modules_init(void)
142{
143 proc_create("modules", 0, NULL, &modules_proc_ops);
144 return 0;
145}
146module_init(proc_modules_init);