Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * kernel/ksysfs.c - sysfs attributes in /sys/kernel, which |
| 3 | * are not related to any other subsystem |
| 4 | * |
| 5 | * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org> |
| 6 | * |
| 7 | * This file is release under the GPLv2 |
| 8 | * |
| 9 | */ |
| 10 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | #include <linux/kobject.h> |
| 12 | #include <linux/string.h> |
| 13 | #include <linux/sysfs.h> |
| 14 | #include <linux/module.h> |
| 15 | #include <linux/init.h> |
Jeff Moyer | c330dda | 2006-06-23 02:05:07 -0700 | [diff] [blame] | 16 | #include <linux/kexec.h> |
Dave Hansen | 22b8ce9 | 2008-10-15 22:01:46 -0700 | [diff] [blame] | 17 | #include <linux/profile.h> |
Dhaval Giani | 5cb350b | 2007-10-15 17:00:14 +0200 | [diff] [blame] | 18 | #include <linux/sched.h> |
Ludwig Nussel | 088ab0b | 2011-02-28 15:57:17 +0100 | [diff] [blame] | 19 | #include <linux/capability.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | |
| 21 | #define KERNEL_ATTR_RO(_name) \ |
Kay Sievers | 386f275 | 2007-11-02 13:47:53 +0100 | [diff] [blame] | 22 | static struct kobj_attribute _name##_attr = __ATTR_RO(_name) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | |
| 24 | #define KERNEL_ATTR_RW(_name) \ |
Kay Sievers | 386f275 | 2007-11-02 13:47:53 +0100 | [diff] [blame] | 25 | static struct kobj_attribute _name##_attr = \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | __ATTR(_name, 0644, _name##_show, _name##_store) |
| 27 | |
Ming Lei | cd3772e | 2008-11-16 18:22:09 +0800 | [diff] [blame] | 28 | #if defined(CONFIG_HOTPLUG) |
Kay Sievers | 0f76e5a | 2005-11-11 04:58:04 +0100 | [diff] [blame] | 29 | /* current uevent sequence number */ |
Kay Sievers | 386f275 | 2007-11-02 13:47:53 +0100 | [diff] [blame] | 30 | static ssize_t uevent_seqnum_show(struct kobject *kobj, |
| 31 | struct kobj_attribute *attr, char *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | { |
Kay Sievers | 386f275 | 2007-11-02 13:47:53 +0100 | [diff] [blame] | 33 | return sprintf(buf, "%llu\n", (unsigned long long)uevent_seqnum); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | } |
Kay Sievers | 0f76e5a | 2005-11-11 04:58:04 +0100 | [diff] [blame] | 35 | KERNEL_ATTR_RO(uevent_seqnum); |
| 36 | |
Thadeu Lima de Souza Cascardo | af66585 | 2010-01-17 19:14:26 -0200 | [diff] [blame] | 37 | /* uevent helper program, used during early boot */ |
Kay Sievers | 386f275 | 2007-11-02 13:47:53 +0100 | [diff] [blame] | 38 | static ssize_t uevent_helper_show(struct kobject *kobj, |
| 39 | struct kobj_attribute *attr, char *buf) |
Kay Sievers | 0f76e5a | 2005-11-11 04:58:04 +0100 | [diff] [blame] | 40 | { |
Kay Sievers | 386f275 | 2007-11-02 13:47:53 +0100 | [diff] [blame] | 41 | return sprintf(buf, "%s\n", uevent_helper); |
Kay Sievers | 0f76e5a | 2005-11-11 04:58:04 +0100 | [diff] [blame] | 42 | } |
Kay Sievers | 386f275 | 2007-11-02 13:47:53 +0100 | [diff] [blame] | 43 | static ssize_t uevent_helper_store(struct kobject *kobj, |
| 44 | struct kobj_attribute *attr, |
| 45 | const char *buf, size_t count) |
Kay Sievers | 0f76e5a | 2005-11-11 04:58:04 +0100 | [diff] [blame] | 46 | { |
Kay Sievers | 312c004 | 2005-11-16 09:00:00 +0100 | [diff] [blame] | 47 | if (count+1 > UEVENT_HELPER_PATH_LEN) |
Kay Sievers | 0f76e5a | 2005-11-11 04:58:04 +0100 | [diff] [blame] | 48 | return -ENOENT; |
Kay Sievers | 386f275 | 2007-11-02 13:47:53 +0100 | [diff] [blame] | 49 | memcpy(uevent_helper, buf, count); |
Kay Sievers | 312c004 | 2005-11-16 09:00:00 +0100 | [diff] [blame] | 50 | uevent_helper[count] = '\0'; |
| 51 | if (count && uevent_helper[count-1] == '\n') |
| 52 | uevent_helper[count-1] = '\0'; |
Kay Sievers | 0f76e5a | 2005-11-11 04:58:04 +0100 | [diff] [blame] | 53 | return count; |
| 54 | } |
| 55 | KERNEL_ATTR_RW(uevent_helper); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 56 | #endif |
| 57 | |
Dave Hansen | 22b8ce9 | 2008-10-15 22:01:46 -0700 | [diff] [blame] | 58 | #ifdef CONFIG_PROFILING |
| 59 | static ssize_t profiling_show(struct kobject *kobj, |
| 60 | struct kobj_attribute *attr, char *buf) |
| 61 | { |
| 62 | return sprintf(buf, "%d\n", prof_on); |
| 63 | } |
| 64 | static ssize_t profiling_store(struct kobject *kobj, |
| 65 | struct kobj_attribute *attr, |
| 66 | const char *buf, size_t count) |
| 67 | { |
| 68 | int ret; |
| 69 | |
| 70 | if (prof_on) |
| 71 | return -EEXIST; |
| 72 | /* |
| 73 | * This eventually calls into get_option() which |
| 74 | * has a ton of callers and is not const. It is |
| 75 | * easiest to cast it away here. |
| 76 | */ |
| 77 | profile_setup((char *)buf); |
| 78 | ret = profile_init(); |
| 79 | if (ret) |
| 80 | return ret; |
| 81 | ret = create_proc_profile(); |
| 82 | if (ret) |
| 83 | return ret; |
| 84 | return count; |
| 85 | } |
| 86 | KERNEL_ATTR_RW(profiling); |
| 87 | #endif |
| 88 | |
Jeff Moyer | c330dda | 2006-06-23 02:05:07 -0700 | [diff] [blame] | 89 | #ifdef CONFIG_KEXEC |
Kay Sievers | 386f275 | 2007-11-02 13:47:53 +0100 | [diff] [blame] | 90 | static ssize_t kexec_loaded_show(struct kobject *kobj, |
| 91 | struct kobj_attribute *attr, char *buf) |
Jeff Moyer | c330dda | 2006-06-23 02:05:07 -0700 | [diff] [blame] | 92 | { |
Kay Sievers | 386f275 | 2007-11-02 13:47:53 +0100 | [diff] [blame] | 93 | return sprintf(buf, "%d\n", !!kexec_image); |
Jeff Moyer | c330dda | 2006-06-23 02:05:07 -0700 | [diff] [blame] | 94 | } |
| 95 | KERNEL_ATTR_RO(kexec_loaded); |
| 96 | |
Kay Sievers | 386f275 | 2007-11-02 13:47:53 +0100 | [diff] [blame] | 97 | static ssize_t kexec_crash_loaded_show(struct kobject *kobj, |
| 98 | struct kobj_attribute *attr, char *buf) |
Jeff Moyer | c330dda | 2006-06-23 02:05:07 -0700 | [diff] [blame] | 99 | { |
Kay Sievers | 386f275 | 2007-11-02 13:47:53 +0100 | [diff] [blame] | 100 | return sprintf(buf, "%d\n", !!kexec_crash_image); |
Jeff Moyer | c330dda | 2006-06-23 02:05:07 -0700 | [diff] [blame] | 101 | } |
| 102 | KERNEL_ATTR_RO(kexec_crash_loaded); |
Ken'ichi Ohmichi | fd59d23 | 2007-10-16 23:27:27 -0700 | [diff] [blame] | 103 | |
Amerigo Wang | 06a7f71 | 2009-12-15 16:47:46 -0800 | [diff] [blame] | 104 | static ssize_t kexec_crash_size_show(struct kobject *kobj, |
| 105 | struct kobj_attribute *attr, char *buf) |
| 106 | { |
| 107 | return sprintf(buf, "%zu\n", crash_get_memory_size()); |
| 108 | } |
| 109 | static ssize_t kexec_crash_size_store(struct kobject *kobj, |
| 110 | struct kobj_attribute *attr, |
| 111 | const char *buf, size_t count) |
| 112 | { |
| 113 | unsigned long cnt; |
| 114 | int ret; |
| 115 | |
| 116 | if (strict_strtoul(buf, 0, &cnt)) |
| 117 | return -EINVAL; |
| 118 | |
| 119 | ret = crash_shrink_memory(cnt); |
| 120 | return ret < 0 ? ret : count; |
| 121 | } |
| 122 | KERNEL_ATTR_RW(kexec_crash_size); |
| 123 | |
Kay Sievers | 386f275 | 2007-11-02 13:47:53 +0100 | [diff] [blame] | 124 | static ssize_t vmcoreinfo_show(struct kobject *kobj, |
| 125 | struct kobj_attribute *attr, char *buf) |
Ken'ichi Ohmichi | fd59d23 | 2007-10-16 23:27:27 -0700 | [diff] [blame] | 126 | { |
Kay Sievers | 386f275 | 2007-11-02 13:47:53 +0100 | [diff] [blame] | 127 | return sprintf(buf, "%lx %x\n", |
Ken'ichi Ohmichi | fd59d23 | 2007-10-16 23:27:27 -0700 | [diff] [blame] | 128 | paddr_vmcoreinfo_note(), |
Ken'ichi Ohmichi | d768281 | 2007-10-16 23:27:28 -0700 | [diff] [blame] | 129 | (unsigned int)vmcoreinfo_max_size); |
Ken'ichi Ohmichi | fd59d23 | 2007-10-16 23:27:27 -0700 | [diff] [blame] | 130 | } |
| 131 | KERNEL_ATTR_RO(vmcoreinfo); |
| 132 | |
Jeff Moyer | c330dda | 2006-06-23 02:05:07 -0700 | [diff] [blame] | 133 | #endif /* CONFIG_KEXEC */ |
| 134 | |
Ludwig Nussel | 088ab0b | 2011-02-28 15:57:17 +0100 | [diff] [blame] | 135 | /* whether file capabilities are enabled */ |
| 136 | static ssize_t fscaps_show(struct kobject *kobj, |
| 137 | struct kobj_attribute *attr, char *buf) |
| 138 | { |
| 139 | return sprintf(buf, "%d\n", file_caps_enabled); |
| 140 | } |
| 141 | KERNEL_ATTR_RO(fscaps); |
| 142 | |
Roland McGrath | da1a679 | 2007-07-19 01:48:39 -0700 | [diff] [blame] | 143 | /* |
| 144 | * Make /sys/kernel/notes give the raw contents of our kernel .notes section. |
| 145 | */ |
David Howells | 0b1937a | 2007-07-20 17:02:04 +0100 | [diff] [blame] | 146 | extern const void __start_notes __attribute__((weak)); |
| 147 | extern const void __stop_notes __attribute__((weak)); |
Roland McGrath | da1a679 | 2007-07-19 01:48:39 -0700 | [diff] [blame] | 148 | #define notes_size (&__stop_notes - &__start_notes) |
| 149 | |
Chris Wright | 2c3c8be | 2010-05-12 18:28:57 -0700 | [diff] [blame] | 150 | static ssize_t notes_read(struct file *filp, struct kobject *kobj, |
| 151 | struct bin_attribute *bin_attr, |
Roland McGrath | da1a679 | 2007-07-19 01:48:39 -0700 | [diff] [blame] | 152 | char *buf, loff_t off, size_t count) |
| 153 | { |
| 154 | memcpy(buf, &__start_notes + off, count); |
| 155 | return count; |
| 156 | } |
| 157 | |
| 158 | static struct bin_attribute notes_attr = { |
| 159 | .attr = { |
| 160 | .name = "notes", |
| 161 | .mode = S_IRUGO, |
| 162 | }, |
| 163 | .read = ¬es_read, |
| 164 | }; |
| 165 | |
Greg Kroah-Hartman | 0ff21e4 | 2007-11-06 10:36:58 -0800 | [diff] [blame] | 166 | struct kobject *kernel_kobj; |
| 167 | EXPORT_SYMBOL_GPL(kernel_kobj); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 168 | |
| 169 | static struct attribute * kernel_attrs[] = { |
Ludwig Nussel | 088ab0b | 2011-02-28 15:57:17 +0100 | [diff] [blame] | 170 | &fscaps_attr.attr, |
Ming Lei | cd3772e | 2008-11-16 18:22:09 +0800 | [diff] [blame] | 171 | #if defined(CONFIG_HOTPLUG) |
Kay Sievers | 0f76e5a | 2005-11-11 04:58:04 +0100 | [diff] [blame] | 172 | &uevent_seqnum_attr.attr, |
| 173 | &uevent_helper_attr.attr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 174 | #endif |
Dave Hansen | 22b8ce9 | 2008-10-15 22:01:46 -0700 | [diff] [blame] | 175 | #ifdef CONFIG_PROFILING |
| 176 | &profiling_attr.attr, |
| 177 | #endif |
Jeff Moyer | c330dda | 2006-06-23 02:05:07 -0700 | [diff] [blame] | 178 | #ifdef CONFIG_KEXEC |
| 179 | &kexec_loaded_attr.attr, |
| 180 | &kexec_crash_loaded_attr.attr, |
Amerigo Wang | 06a7f71 | 2009-12-15 16:47:46 -0800 | [diff] [blame] | 181 | &kexec_crash_size_attr.attr, |
Ken'ichi Ohmichi | fd59d23 | 2007-10-16 23:27:27 -0700 | [diff] [blame] | 182 | &vmcoreinfo_attr.attr, |
Jeff Moyer | c330dda | 2006-06-23 02:05:07 -0700 | [diff] [blame] | 183 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 184 | NULL |
| 185 | }; |
| 186 | |
| 187 | static struct attribute_group kernel_attr_group = { |
| 188 | .attrs = kernel_attrs, |
| 189 | }; |
| 190 | |
| 191 | static int __init ksysfs_init(void) |
| 192 | { |
Greg Kroah-Hartman | bd35b93 | 2007-10-29 20:13:17 +0100 | [diff] [blame] | 193 | int error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | |
Greg Kroah-Hartman | 0ff21e4 | 2007-11-06 10:36:58 -0800 | [diff] [blame] | 195 | kernel_kobj = kobject_create_and_add("kernel", NULL); |
| 196 | if (!kernel_kobj) { |
Greg Kroah-Hartman | bd35b93 | 2007-10-29 20:13:17 +0100 | [diff] [blame] | 197 | error = -ENOMEM; |
| 198 | goto exit; |
| 199 | } |
Greg Kroah-Hartman | 0ff21e4 | 2007-11-06 10:36:58 -0800 | [diff] [blame] | 200 | error = sysfs_create_group(kernel_kobj, &kernel_attr_group); |
Greg Kroah-Hartman | bd35b93 | 2007-10-29 20:13:17 +0100 | [diff] [blame] | 201 | if (error) |
| 202 | goto kset_exit; |
| 203 | |
| 204 | if (notes_size > 0) { |
Roland McGrath | da1a679 | 2007-07-19 01:48:39 -0700 | [diff] [blame] | 205 | notes_attr.size = notes_size; |
Greg Kroah-Hartman | 0ff21e4 | 2007-11-06 10:36:58 -0800 | [diff] [blame] | 206 | error = sysfs_create_bin_file(kernel_kobj, ¬es_attr); |
Greg Kroah-Hartman | bd35b93 | 2007-10-29 20:13:17 +0100 | [diff] [blame] | 207 | if (error) |
| 208 | goto group_exit; |
Roland McGrath | da1a679 | 2007-07-19 01:48:39 -0700 | [diff] [blame] | 209 | } |
| 210 | |
Greg Kroah-Hartman | bd35b93 | 2007-10-29 20:13:17 +0100 | [diff] [blame] | 211 | return 0; |
| 212 | |
Greg Kroah-Hartman | bd35b93 | 2007-10-29 20:13:17 +0100 | [diff] [blame] | 213 | group_exit: |
Greg Kroah-Hartman | 0ff21e4 | 2007-11-06 10:36:58 -0800 | [diff] [blame] | 214 | sysfs_remove_group(kernel_kobj, &kernel_attr_group); |
Greg Kroah-Hartman | bd35b93 | 2007-10-29 20:13:17 +0100 | [diff] [blame] | 215 | kset_exit: |
Greg Kroah-Hartman | 78a2d90 | 2007-12-20 08:13:05 -0800 | [diff] [blame] | 216 | kobject_put(kernel_kobj); |
Greg Kroah-Hartman | bd35b93 | 2007-10-29 20:13:17 +0100 | [diff] [blame] | 217 | exit: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 218 | return error; |
| 219 | } |
| 220 | |
| 221 | core_initcall(ksysfs_init); |