mutex: Fix annotations to include it in kernel-locking docbook
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / kernel / sysctl.c
CommitLineData
1da177e4
LT
1/*
2 * sysctl.c: General linux system control interface
3 *
4 * Begun 24 March 1995, Stephen Tweedie
5 * Added /proc support, Dec 1995
6 * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
7 * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
8 * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
9 * Dynamic registration fixes, Stephen Tweedie.
10 * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
11 * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
12 * Horn.
13 * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
14 * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
15 * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
16 * Wendling.
17 * The list_for_each() macro wasn't appropriate for the sysctl loop.
18 * Removed it and replaced it with older style, 03/23/00, Bill Wendling
19 */
20
1da177e4
LT
21#include <linux/module.h>
22#include <linux/mm.h>
23#include <linux/swap.h>
24#include <linux/slab.h>
25#include <linux/sysctl.h>
d33ed52d 26#include <linux/signal.h>
1da177e4 27#include <linux/proc_fs.h>
72c2d582 28#include <linux/security.h>
1da177e4 29#include <linux/ctype.h>
dfec072e 30#include <linux/kmemcheck.h>
62239ac2 31#include <linux/fs.h>
1da177e4
LT
32#include <linux/init.h>
33#include <linux/kernel.h>
0296b228 34#include <linux/kobject.h>
20380731 35#include <linux/net.h>
1da177e4
LT
36#include <linux/sysrq.h>
37#include <linux/highuid.h>
38#include <linux/writeback.h>
3fff4c42 39#include <linux/ratelimit.h>
76ab0f53 40#include <linux/compaction.h>
1da177e4 41#include <linux/hugetlb.h>
1da177e4 42#include <linux/initrd.h>
0b77f5bf 43#include <linux/key.h>
1da177e4
LT
44#include <linux/times.h>
45#include <linux/limits.h>
46#include <linux/dcache.h>
6e006701 47#include <linux/dnotify.h>
1da177e4 48#include <linux/syscalls.h>
c748e134 49#include <linux/vmstat.h>
c255d844
PM
50#include <linux/nfs_fs.h>
51#include <linux/acpi.h>
10a0a8d4 52#include <linux/reboot.h>
b0fc494f 53#include <linux/ftrace.h>
cdd6c482 54#include <linux/perf_event.h>
b2be84df 55#include <linux/kprobes.h>
b492e95b 56#include <linux/pipe_fs_i.h>
8e4228e1 57#include <linux/oom.h>
1da177e4
LT
58
59#include <asm/uaccess.h>
60#include <asm/processor.h>
61
29cbc78b
AK
62#ifdef CONFIG_X86
63#include <asm/nmi.h>
0741f4d2 64#include <asm/stacktrace.h>
6e7c4025 65#include <asm/io.h>
29cbc78b 66#endif
c55b7c3e
DY
67#ifdef CONFIG_BSD_PROCESS_ACCT
68#include <linux/acct.h>
69#endif
4f0e056f
DY
70#ifdef CONFIG_RT_MUTEXES
71#include <linux/rtmutex.h>
72#endif
2edf5e49
DY
73#if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT)
74#include <linux/lockdep.h>
75#endif
15485a46
DY
76#ifdef CONFIG_CHR_DEV_SG
77#include <scsi/sg.h>
78#endif
29cbc78b 79
58687acb 80#ifdef CONFIG_LOCKUP_DETECTOR
504d7cf1
DZ
81#include <linux/nmi.h>
82#endif
83
7058cb02 84
1da177e4
LT
85#if defined(CONFIG_SYSCTL)
86
87/* External variables not in a header file. */
1da177e4
LT
88extern int sysctl_overcommit_memory;
89extern int sysctl_overcommit_ratio;
90extern int max_threads;
1da177e4 91extern int core_uses_pid;
d6e71144 92extern int suid_dumpable;
1da177e4 93extern char core_pattern[];
a293980c 94extern unsigned int core_pipe_limit;
1da177e4
LT
95extern int pid_max;
96extern int min_free_kbytes;
1da177e4 97extern int pid_max_min, pid_max_max;
9d0243bc 98extern int sysctl_drop_caches;
8ad4b1fb 99extern int percpu_pagelist_fraction;
bebfa101 100extern int compat_log;
9745512c 101extern int latencytop_enabled;
eceea0b3 102extern int sysctl_nr_open_min, sysctl_nr_open_max;
dd8632a1
PM
103#ifndef CONFIG_MMU
104extern int sysctl_nr_trim_pages;
105#endif
cb684b5b 106#ifdef CONFIG_BLOCK
5e605b64 107extern int blk_iopoll_enabled;
cb684b5b 108#endif
1da177e4 109
c4f3b63f 110/* Constants used for minimum and maximum */
2508ce18 111#ifdef CONFIG_LOCKUP_DETECTOR
c4f3b63f 112static int sixty = 60;
9383d967 113static int neg_one = -1;
c4f3b63f
RT
114#endif
115
c4f3b63f 116static int zero;
cd5f9a4c
LT
117static int __maybe_unused one = 1;
118static int __maybe_unused two = 2;
fc3501d4 119static unsigned long one_ul = 1;
c4f3b63f 120static int one_hundred = 100;
af91322e
DY
121#ifdef CONFIG_PRINTK
122static int ten_thousand = 10000;
123#endif
c4f3b63f 124
9e4a5bda
AR
125/* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
126static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
127
1da177e4
LT
128/* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
129static int maxolduid = 65535;
130static int minolduid;
8ad4b1fb 131static int min_percpu_pagelist_fract = 8;
1da177e4
LT
132
133static int ngroups_max = NGROUPS_MAX;
134
d14f1729
DY
135#ifdef CONFIG_INOTIFY_USER
136#include <linux/inotify.h>
137#endif
72c57ed5 138#ifdef CONFIG_SPARC
17f04fbb 139#include <asm/system.h>
1da177e4
LT
140#endif
141
0871420f
DM
142#ifdef CONFIG_SPARC64
143extern int sysctl_tsb_ratio;
144#endif
145
1da177e4
LT
146#ifdef __hppa__
147extern int pwrsw_enabled;
148extern int unaligned_enabled;
149#endif
150
347a8dc3 151#ifdef CONFIG_S390
1da177e4
LT
152#ifdef CONFIG_MATHEMU
153extern int sysctl_ieee_emulation_warnings;
154#endif
155extern int sysctl_userprocess_debug;
951f22d5 156extern int spin_retry;
1da177e4
LT
157#endif
158
d2b176ed
JS
159#ifdef CONFIG_IA64
160extern int no_unaligned_warning;
88fc241f 161extern int unaligned_dump_stack;
d2b176ed
JS
162#endif
163
3fff4c42
IM
164extern struct ratelimit_state printk_ratelimit_state;
165
d6f8ff73 166#ifdef CONFIG_PROC_SYSCTL
8d65af78 167static int proc_do_cad_pid(struct ctl_table *table, int write,
9ec52099 168 void __user *buffer, size_t *lenp, loff_t *ppos);
8d65af78 169static int proc_taint(struct ctl_table *table, int write,
34f5a398 170 void __user *buffer, size_t *lenp, loff_t *ppos);
d6f8ff73 171#endif
9ec52099 172
97f5f0cd
DT
173#ifdef CONFIG_MAGIC_SYSRQ
174static int __sysrq_enabled; /* Note: sysrq code ises it's own private copy */
175
176static int sysrq_sysctl_handler(ctl_table *table, int write,
177 void __user *buffer, size_t *lenp,
178 loff_t *ppos)
179{
180 int error;
181
182 error = proc_dointvec(table, write, buffer, lenp, ppos);
183 if (error)
184 return error;
185
186 if (write)
187 sysrq_toggle_support(__sysrq_enabled);
188
189 return 0;
190}
191
192#endif
193
d8217f07 194static struct ctl_table root_table[];
e51b6ba0
EB
195static struct ctl_table_root sysctl_table_root;
196static struct ctl_table_header root_table_header = {
b380b0d4 197 .count = 1,
e51b6ba0 198 .ctl_table = root_table,
73455092 199 .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
e51b6ba0 200 .root = &sysctl_table_root,
73455092 201 .set = &sysctl_table_root.default_set,
e51b6ba0
EB
202};
203static struct ctl_table_root sysctl_table_root = {
204 .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
73455092 205 .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
e51b6ba0 206};
1da177e4 207
d8217f07
EB
208static struct ctl_table kern_table[];
209static struct ctl_table vm_table[];
210static struct ctl_table fs_table[];
211static struct ctl_table debug_table[];
212static struct ctl_table dev_table[];
213extern struct ctl_table random_table[];
7ef9964e
DL
214#ifdef CONFIG_EPOLL
215extern struct ctl_table epoll_table[];
216#endif
1da177e4
LT
217
218#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
219int sysctl_legacy_va_layout;
220#endif
221
1da177e4
LT
222/* The default sysctl tables: */
223
d8217f07 224static struct ctl_table root_table[] = {
1da177e4 225 {
1da177e4
LT
226 .procname = "kernel",
227 .mode = 0555,
228 .child = kern_table,
229 },
230 {
1da177e4
LT
231 .procname = "vm",
232 .mode = 0555,
233 .child = vm_table,
234 },
1da177e4 235 {
1da177e4
LT
236 .procname = "fs",
237 .mode = 0555,
238 .child = fs_table,
239 },
240 {
1da177e4
LT
241 .procname = "debug",
242 .mode = 0555,
243 .child = debug_table,
244 },
245 {
1da177e4
LT
246 .procname = "dev",
247 .mode = 0555,
248 .child = dev_table,
249 },
2be7fe07
AM
250/*
251 * NOTE: do not add new entries to this table unless you have read
252 * Documentation/sysctl/ctl_unnumbered.txt
253 */
6fce56ec 254 { }
1da177e4
LT
255};
256
77e54a1f 257#ifdef CONFIG_SCHED_DEBUG
73c4efd2
ED
258static int min_sched_granularity_ns = 100000; /* 100 usecs */
259static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
260static int min_wakeup_granularity_ns; /* 0 usecs */
261static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
1983a922
CE
262static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
263static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
acb4a848
CE
264static int min_sched_shares_ratelimit = 100000; /* 100 usec */
265static int max_sched_shares_ratelimit = NSEC_PER_SEC; /* 1 second */
77e54a1f
IM
266#endif
267
5e771905
MG
268#ifdef CONFIG_COMPACTION
269static int min_extfrag_threshold;
270static int max_extfrag_threshold = 1000;
271#endif
272
d8217f07 273static struct ctl_table kern_table[] = {
2bba22c5 274 {
2bba22c5
MG
275 .procname = "sched_child_runs_first",
276 .data = &sysctl_sched_child_runs_first,
277 .maxlen = sizeof(unsigned int),
278 .mode = 0644,
6d456111 279 .proc_handler = proc_dointvec,
2bba22c5 280 },
77e54a1f
IM
281#ifdef CONFIG_SCHED_DEBUG
282 {
b2be5e96
PZ
283 .procname = "sched_min_granularity_ns",
284 .data = &sysctl_sched_min_granularity,
77e54a1f
IM
285 .maxlen = sizeof(unsigned int),
286 .mode = 0644,
702a7c76 287 .proc_handler = sched_proc_update_handler,
b2be5e96
PZ
288 .extra1 = &min_sched_granularity_ns,
289 .extra2 = &max_sched_granularity_ns,
77e54a1f 290 },
21805085 291 {
21805085
PZ
292 .procname = "sched_latency_ns",
293 .data = &sysctl_sched_latency,
294 .maxlen = sizeof(unsigned int),
295 .mode = 0644,
702a7c76 296 .proc_handler = sched_proc_update_handler,
21805085
PZ
297 .extra1 = &min_sched_granularity_ns,
298 .extra2 = &max_sched_granularity_ns,
299 },
77e54a1f 300 {
77e54a1f
IM
301 .procname = "sched_wakeup_granularity_ns",
302 .data = &sysctl_sched_wakeup_granularity,
303 .maxlen = sizeof(unsigned int),
304 .mode = 0644,
702a7c76 305 .proc_handler = sched_proc_update_handler,
77e54a1f
IM
306 .extra1 = &min_wakeup_granularity_ns,
307 .extra2 = &max_wakeup_granularity_ns,
308 },
2398f2c6 309 {
2398f2c6
PZ
310 .procname = "sched_shares_ratelimit",
311 .data = &sysctl_sched_shares_ratelimit,
312 .maxlen = sizeof(unsigned int),
313 .mode = 0644,
702a7c76 314 .proc_handler = sched_proc_update_handler,
acb4a848
CE
315 .extra1 = &min_sched_shares_ratelimit,
316 .extra2 = &max_sched_shares_ratelimit,
2398f2c6 317 },
1983a922 318 {
1983a922
CE
319 .procname = "sched_tunable_scaling",
320 .data = &sysctl_sched_tunable_scaling,
321 .maxlen = sizeof(enum sched_tunable_scaling),
322 .mode = 0644,
702a7c76 323 .proc_handler = sched_proc_update_handler,
1983a922
CE
324 .extra1 = &min_sched_tunable_scaling,
325 .extra2 = &max_sched_tunable_scaling,
2398f2c6 326 },
ffda12a1 327 {
ffda12a1
PZ
328 .procname = "sched_shares_thresh",
329 .data = &sysctl_sched_shares_thresh,
330 .maxlen = sizeof(unsigned int),
331 .mode = 0644,
6d456111 332 .proc_handler = proc_dointvec_minmax,
ffda12a1
PZ
333 .extra1 = &zero,
334 },
da84d961 335 {
da84d961
IM
336 .procname = "sched_migration_cost",
337 .data = &sysctl_sched_migration_cost,
338 .maxlen = sizeof(unsigned int),
339 .mode = 0644,
6d456111 340 .proc_handler = proc_dointvec,
da84d961 341 },
b82d9fdd 342 {
b82d9fdd
PZ
343 .procname = "sched_nr_migrate",
344 .data = &sysctl_sched_nr_migrate,
345 .maxlen = sizeof(unsigned int),
fa85ae24 346 .mode = 0644,
6d456111 347 .proc_handler = proc_dointvec,
fa85ae24 348 },
e9e9250b 349 {
e9e9250b
PZ
350 .procname = "sched_time_avg",
351 .data = &sysctl_sched_time_avg,
352 .maxlen = sizeof(unsigned int),
353 .mode = 0644,
6d456111 354 .proc_handler = proc_dointvec,
e9e9250b 355 },
cd1bb94b 356 {
cd1bb94b
AB
357 .procname = "timer_migration",
358 .data = &sysctl_timer_migration,
359 .maxlen = sizeof(unsigned int),
360 .mode = 0644,
6d456111 361 .proc_handler = proc_dointvec_minmax,
bfdb4d9f
AB
362 .extra1 = &zero,
363 .extra2 = &one,
fa85ae24 364 },
1fc84aaa 365#endif
9f0c1e56 366 {
9f0c1e56
PZ
367 .procname = "sched_rt_period_us",
368 .data = &sysctl_sched_rt_period,
369 .maxlen = sizeof(unsigned int),
370 .mode = 0644,
6d456111 371 .proc_handler = sched_rt_handler,
9f0c1e56
PZ
372 },
373 {
9f0c1e56
PZ
374 .procname = "sched_rt_runtime_us",
375 .data = &sysctl_sched_rt_runtime,
376 .maxlen = sizeof(int),
377 .mode = 0644,
6d456111 378 .proc_handler = sched_rt_handler,
9f0c1e56 379 },
1799e35d 380 {
1799e35d
IM
381 .procname = "sched_compat_yield",
382 .data = &sysctl_sched_compat_yield,
383 .maxlen = sizeof(unsigned int),
384 .mode = 0644,
6d456111 385 .proc_handler = proc_dointvec,
1799e35d 386 },
f20786ff
PZ
387#ifdef CONFIG_PROVE_LOCKING
388 {
f20786ff
PZ
389 .procname = "prove_locking",
390 .data = &prove_locking,
391 .maxlen = sizeof(int),
392 .mode = 0644,
6d456111 393 .proc_handler = proc_dointvec,
f20786ff
PZ
394 },
395#endif
396#ifdef CONFIG_LOCK_STAT
397 {
f20786ff
PZ
398 .procname = "lock_stat",
399 .data = &lock_stat,
400 .maxlen = sizeof(int),
401 .mode = 0644,
6d456111 402 .proc_handler = proc_dointvec,
f20786ff 403 },
77e54a1f 404#endif
1da177e4 405 {
1da177e4
LT
406 .procname = "panic",
407 .data = &panic_timeout,
408 .maxlen = sizeof(int),
409 .mode = 0644,
6d456111 410 .proc_handler = proc_dointvec,
1da177e4
LT
411 },
412 {
1da177e4
LT
413 .procname = "core_uses_pid",
414 .data = &core_uses_pid,
415 .maxlen = sizeof(int),
416 .mode = 0644,
6d456111 417 .proc_handler = proc_dointvec,
1da177e4
LT
418 },
419 {
1da177e4
LT
420 .procname = "core_pattern",
421 .data = core_pattern,
71ce92f3 422 .maxlen = CORENAME_MAX_SIZE,
1da177e4 423 .mode = 0644,
6d456111 424 .proc_handler = proc_dostring,
1da177e4 425 },
a293980c 426 {
a293980c
NH
427 .procname = "core_pipe_limit",
428 .data = &core_pipe_limit,
429 .maxlen = sizeof(unsigned int),
430 .mode = 0644,
6d456111 431 .proc_handler = proc_dointvec,
a293980c 432 },
34f5a398 433#ifdef CONFIG_PROC_SYSCTL
1da177e4 434 {
1da177e4 435 .procname = "tainted",
25ddbb18 436 .maxlen = sizeof(long),
34f5a398 437 .mode = 0644,
6d456111 438 .proc_handler = proc_taint,
1da177e4 439 },
34f5a398 440#endif
9745512c
AV
441#ifdef CONFIG_LATENCYTOP
442 {
443 .procname = "latencytop",
444 .data = &latencytop_enabled,
445 .maxlen = sizeof(int),
446 .mode = 0644,
6d456111 447 .proc_handler = proc_dointvec,
9745512c
AV
448 },
449#endif
1da177e4
LT
450#ifdef CONFIG_BLK_DEV_INITRD
451 {
1da177e4
LT
452 .procname = "real-root-dev",
453 .data = &real_root_dev,
454 .maxlen = sizeof(int),
455 .mode = 0644,
6d456111 456 .proc_handler = proc_dointvec,
1da177e4
LT
457 },
458#endif
45807a1d 459 {
45807a1d
IM
460 .procname = "print-fatal-signals",
461 .data = &print_fatal_signals,
462 .maxlen = sizeof(int),
463 .mode = 0644,
6d456111 464 .proc_handler = proc_dointvec,
45807a1d 465 },
72c57ed5 466#ifdef CONFIG_SPARC
1da177e4 467 {
1da177e4
LT
468 .procname = "reboot-cmd",
469 .data = reboot_command,
470 .maxlen = 256,
471 .mode = 0644,
6d456111 472 .proc_handler = proc_dostring,
1da177e4
LT
473 },
474 {
1da177e4
LT
475 .procname = "stop-a",
476 .data = &stop_a_enabled,
477 .maxlen = sizeof (int),
478 .mode = 0644,
6d456111 479 .proc_handler = proc_dointvec,
1da177e4
LT
480 },
481 {
1da177e4
LT
482 .procname = "scons-poweroff",
483 .data = &scons_pwroff,
484 .maxlen = sizeof (int),
485 .mode = 0644,
6d456111 486 .proc_handler = proc_dointvec,
1da177e4
LT
487 },
488#endif
0871420f
DM
489#ifdef CONFIG_SPARC64
490 {
0871420f
DM
491 .procname = "tsb-ratio",
492 .data = &sysctl_tsb_ratio,
493 .maxlen = sizeof (int),
494 .mode = 0644,
6d456111 495 .proc_handler = proc_dointvec,
0871420f
DM
496 },
497#endif
1da177e4
LT
498#ifdef __hppa__
499 {
1da177e4
LT
500 .procname = "soft-power",
501 .data = &pwrsw_enabled,
502 .maxlen = sizeof (int),
503 .mode = 0644,
6d456111 504 .proc_handler = proc_dointvec,
1da177e4
LT
505 },
506 {
1da177e4
LT
507 .procname = "unaligned-trap",
508 .data = &unaligned_enabled,
509 .maxlen = sizeof (int),
510 .mode = 0644,
6d456111 511 .proc_handler = proc_dointvec,
1da177e4
LT
512 },
513#endif
514 {
1da177e4
LT
515 .procname = "ctrl-alt-del",
516 .data = &C_A_D,
517 .maxlen = sizeof(int),
518 .mode = 0644,
6d456111 519 .proc_handler = proc_dointvec,
1da177e4 520 },
606576ce 521#ifdef CONFIG_FUNCTION_TRACER
b0fc494f 522 {
b0fc494f
SR
523 .procname = "ftrace_enabled",
524 .data = &ftrace_enabled,
525 .maxlen = sizeof(int),
526 .mode = 0644,
6d456111 527 .proc_handler = ftrace_enable_sysctl,
b0fc494f
SR
528 },
529#endif
f38f1d2a
SR
530#ifdef CONFIG_STACK_TRACER
531 {
f38f1d2a
SR
532 .procname = "stack_tracer_enabled",
533 .data = &stack_tracer_enabled,
534 .maxlen = sizeof(int),
535 .mode = 0644,
6d456111 536 .proc_handler = stack_trace_sysctl,
f38f1d2a
SR
537 },
538#endif
944ac425
SR
539#ifdef CONFIG_TRACING
540 {
3299b4dd 541 .procname = "ftrace_dump_on_oops",
944ac425
SR
542 .data = &ftrace_dump_on_oops,
543 .maxlen = sizeof(int),
544 .mode = 0644,
6d456111 545 .proc_handler = proc_dointvec,
944ac425
SR
546 },
547#endif
a1ef5adb 548#ifdef CONFIG_MODULES
1da177e4 549 {
1da177e4
LT
550 .procname = "modprobe",
551 .data = &modprobe_path,
552 .maxlen = KMOD_PATH_LEN,
553 .mode = 0644,
6d456111 554 .proc_handler = proc_dostring,
1da177e4 555 },
3d43321b 556 {
3d43321b
KC
557 .procname = "modules_disabled",
558 .data = &modules_disabled,
559 .maxlen = sizeof(int),
560 .mode = 0644,
561 /* only handle a transition from default "0" to "1" */
6d456111 562 .proc_handler = proc_dointvec_minmax,
3d43321b
KC
563 .extra1 = &one,
564 .extra2 = &one,
565 },
1da177e4 566#endif
94f17cd7 567#ifdef CONFIG_HOTPLUG
1da177e4 568 {
1da177e4 569 .procname = "hotplug",
312c004d
KS
570 .data = &uevent_helper,
571 .maxlen = UEVENT_HELPER_PATH_LEN,
1da177e4 572 .mode = 0644,
6d456111 573 .proc_handler = proc_dostring,
1da177e4
LT
574 },
575#endif
576#ifdef CONFIG_CHR_DEV_SG
577 {
1da177e4
LT
578 .procname = "sg-big-buff",
579 .data = &sg_big_buff,
580 .maxlen = sizeof (int),
581 .mode = 0444,
6d456111 582 .proc_handler = proc_dointvec,
1da177e4
LT
583 },
584#endif
585#ifdef CONFIG_BSD_PROCESS_ACCT
586 {
1da177e4
LT
587 .procname = "acct",
588 .data = &acct_parm,
589 .maxlen = 3*sizeof(int),
590 .mode = 0644,
6d456111 591 .proc_handler = proc_dointvec,
1da177e4
LT
592 },
593#endif
1da177e4
LT
594#ifdef CONFIG_MAGIC_SYSRQ
595 {
1da177e4 596 .procname = "sysrq",
5d6f647f 597 .data = &__sysrq_enabled,
1da177e4
LT
598 .maxlen = sizeof (int),
599 .mode = 0644,
97f5f0cd 600 .proc_handler = sysrq_sysctl_handler,
1da177e4
LT
601 },
602#endif
d6f8ff73 603#ifdef CONFIG_PROC_SYSCTL
1da177e4 604 {
1da177e4 605 .procname = "cad_pid",
9ec52099 606 .data = NULL,
1da177e4
LT
607 .maxlen = sizeof (int),
608 .mode = 0600,
6d456111 609 .proc_handler = proc_do_cad_pid,
1da177e4 610 },
d6f8ff73 611#endif
1da177e4 612 {
1da177e4
LT
613 .procname = "threads-max",
614 .data = &max_threads,
615 .maxlen = sizeof(int),
616 .mode = 0644,
6d456111 617 .proc_handler = proc_dointvec,
1da177e4
LT
618 },
619 {
1da177e4
LT
620 .procname = "random",
621 .mode = 0555,
622 .child = random_table,
623 },
1da177e4 624 {
1da177e4
LT
625 .procname = "overflowuid",
626 .data = &overflowuid,
627 .maxlen = sizeof(int),
628 .mode = 0644,
6d456111 629 .proc_handler = proc_dointvec_minmax,
1da177e4
LT
630 .extra1 = &minolduid,
631 .extra2 = &maxolduid,
632 },
633 {
1da177e4
LT
634 .procname = "overflowgid",
635 .data = &overflowgid,
636 .maxlen = sizeof(int),
637 .mode = 0644,
6d456111 638 .proc_handler = proc_dointvec_minmax,
1da177e4
LT
639 .extra1 = &minolduid,
640 .extra2 = &maxolduid,
641 },
347a8dc3 642#ifdef CONFIG_S390
1da177e4
LT
643#ifdef CONFIG_MATHEMU
644 {
1da177e4
LT
645 .procname = "ieee_emulation_warnings",
646 .data = &sysctl_ieee_emulation_warnings,
647 .maxlen = sizeof(int),
648 .mode = 0644,
6d456111 649 .proc_handler = proc_dointvec,
1da177e4 650 },
1da177e4
LT
651#endif
652 {
1da177e4 653 .procname = "userprocess_debug",
ab3c68ee 654 .data = &show_unhandled_signals,
1da177e4
LT
655 .maxlen = sizeof(int),
656 .mode = 0644,
6d456111 657 .proc_handler = proc_dointvec,
1da177e4
LT
658 },
659#endif
660 {
1da177e4
LT
661 .procname = "pid_max",
662 .data = &pid_max,
663 .maxlen = sizeof (int),
664 .mode = 0644,
6d456111 665 .proc_handler = proc_dointvec_minmax,
1da177e4
LT
666 .extra1 = &pid_max_min,
667 .extra2 = &pid_max_max,
668 },
669 {
1da177e4
LT
670 .procname = "panic_on_oops",
671 .data = &panic_on_oops,
672 .maxlen = sizeof(int),
673 .mode = 0644,
6d456111 674 .proc_handler = proc_dointvec,
1da177e4 675 },
7ef3d2fd
JP
676#if defined CONFIG_PRINTK
677 {
7ef3d2fd
JP
678 .procname = "printk",
679 .data = &console_loglevel,
680 .maxlen = 4*sizeof(int),
681 .mode = 0644,
6d456111 682 .proc_handler = proc_dointvec,
7ef3d2fd 683 },
1da177e4 684 {
1da177e4 685 .procname = "printk_ratelimit",
717115e1 686 .data = &printk_ratelimit_state.interval,
1da177e4
LT
687 .maxlen = sizeof(int),
688 .mode = 0644,
6d456111 689 .proc_handler = proc_dointvec_jiffies,
1da177e4
LT
690 },
691 {
1da177e4 692 .procname = "printk_ratelimit_burst",
717115e1 693 .data = &printk_ratelimit_state.burst,
1da177e4
LT
694 .maxlen = sizeof(int),
695 .mode = 0644,
6d456111 696 .proc_handler = proc_dointvec,
1da177e4 697 },
af91322e 698 {
af91322e
DY
699 .procname = "printk_delay",
700 .data = &printk_delay_msec,
701 .maxlen = sizeof(int),
702 .mode = 0644,
6d456111 703 .proc_handler = proc_dointvec_minmax,
af91322e
DY
704 .extra1 = &zero,
705 .extra2 = &ten_thousand,
706 },
7ef3d2fd 707#endif
1da177e4 708 {
1da177e4
LT
709 .procname = "ngroups_max",
710 .data = &ngroups_max,
711 .maxlen = sizeof (int),
712 .mode = 0444,
6d456111 713 .proc_handler = proc_dointvec,
1da177e4 714 },
58687acb 715#if defined(CONFIG_LOCKUP_DETECTOR)
504d7cf1 716 {
58687acb
DZ
717 .procname = "watchdog",
718 .data = &watchdog_enabled,
504d7cf1
DZ
719 .maxlen = sizeof (int),
720 .mode = 0644,
58687acb
DZ
721 .proc_handler = proc_dowatchdog_enabled,
722 },
723 {
724 .procname = "watchdog_thresh",
725 .data = &softlockup_thresh,
726 .maxlen = sizeof(int),
727 .mode = 0644,
728 .proc_handler = proc_dowatchdog_thresh,
729 .extra1 = &neg_one,
730 .extra2 = &sixty,
504d7cf1 731 },
2508ce18
DZ
732 {
733 .procname = "softlockup_panic",
734 .data = &softlockup_panic,
735 .maxlen = sizeof(int),
736 .mode = 0644,
737 .proc_handler = proc_dointvec_minmax,
738 .extra1 = &zero,
739 .extra2 = &one,
740 },
504d7cf1 741#endif
58687acb 742#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) && !defined(CONFIG_LOCKUP_DETECTOR)
1da177e4 743 {
1da177e4
LT
744 .procname = "unknown_nmi_panic",
745 .data = &unknown_nmi_panic,
746 .maxlen = sizeof (int),
747 .mode = 0644,
6d456111 748 .proc_handler = proc_dointvec,
1da177e4 749 },
407984f1 750 {
407984f1
DZ
751 .procname = "nmi_watchdog",
752 .data = &nmi_watchdog_enabled,
753 .maxlen = sizeof (int),
754 .mode = 0644,
6d456111 755 .proc_handler = proc_nmi_enabled,
1da177e4
LT
756 },
757#endif
758#if defined(CONFIG_X86)
8da5adda 759 {
8da5adda
DZ
760 .procname = "panic_on_unrecovered_nmi",
761 .data = &panic_on_unrecovered_nmi,
762 .maxlen = sizeof(int),
763 .mode = 0644,
6d456111 764 .proc_handler = proc_dointvec,
8da5adda 765 },
5211a242 766 {
5211a242
KG
767 .procname = "panic_on_io_nmi",
768 .data = &panic_on_io_nmi,
769 .maxlen = sizeof(int),
770 .mode = 0644,
6d456111 771 .proc_handler = proc_dointvec,
5211a242 772 },
1da177e4 773 {
1da177e4
LT
774 .procname = "bootloader_type",
775 .data = &bootloader_type,
776 .maxlen = sizeof (int),
777 .mode = 0444,
6d456111 778 .proc_handler = proc_dointvec,
1da177e4 779 },
5031296c 780 {
5031296c
PA
781 .procname = "bootloader_version",
782 .data = &bootloader_version,
783 .maxlen = sizeof (int),
784 .mode = 0444,
6d456111 785 .proc_handler = proc_dointvec,
5031296c 786 },
0741f4d2 787 {
0741f4d2
CE
788 .procname = "kstack_depth_to_print",
789 .data = &kstack_depth_to_print,
790 .maxlen = sizeof(int),
791 .mode = 0644,
6d456111 792 .proc_handler = proc_dointvec,
0741f4d2 793 },
6e7c4025 794 {
6e7c4025
IM
795 .procname = "io_delay_type",
796 .data = &io_delay_type,
797 .maxlen = sizeof(int),
798 .mode = 0644,
6d456111 799 .proc_handler = proc_dointvec,
6e7c4025 800 },
1da177e4 801#endif
7a9166e3 802#if defined(CONFIG_MMU)
1da177e4 803 {
1da177e4
LT
804 .procname = "randomize_va_space",
805 .data = &randomize_va_space,
806 .maxlen = sizeof(int),
807 .mode = 0644,
6d456111 808 .proc_handler = proc_dointvec,
1da177e4 809 },
7a9166e3 810#endif
0152fb37 811#if defined(CONFIG_S390) && defined(CONFIG_SMP)
951f22d5 812 {
951f22d5
MS
813 .procname = "spin_retry",
814 .data = &spin_retry,
815 .maxlen = sizeof (int),
816 .mode = 0644,
6d456111 817 .proc_handler = proc_dointvec,
951f22d5 818 },
c255d844 819#endif
673d5b43 820#if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
c255d844 821 {
c255d844 822 .procname = "acpi_video_flags",
77afcf78 823 .data = &acpi_realmode_flags,
c255d844
PM
824 .maxlen = sizeof (unsigned long),
825 .mode = 0644,
6d456111 826 .proc_handler = proc_doulongvec_minmax,
c255d844 827 },
d2b176ed
JS
828#endif
829#ifdef CONFIG_IA64
830 {
d2b176ed
JS
831 .procname = "ignore-unaligned-usertrap",
832 .data = &no_unaligned_warning,
833 .maxlen = sizeof (int),
834 .mode = 0644,
6d456111 835 .proc_handler = proc_dointvec,
d2b176ed 836 },
88fc241f 837 {
88fc241f
DC
838 .procname = "unaligned-dump-stack",
839 .data = &unaligned_dump_stack,
840 .maxlen = sizeof (int),
841 .mode = 0644,
6d456111 842 .proc_handler = proc_dointvec,
88fc241f 843 },
bebfa101 844#endif
e162b39a
MSB
845#ifdef CONFIG_DETECT_HUNG_TASK
846 {
e162b39a
MSB
847 .procname = "hung_task_panic",
848 .data = &sysctl_hung_task_panic,
849 .maxlen = sizeof(int),
850 .mode = 0644,
6d456111 851 .proc_handler = proc_dointvec_minmax,
e162b39a
MSB
852 .extra1 = &zero,
853 .extra2 = &one,
854 },
82a1fcb9 855 {
82a1fcb9
IM
856 .procname = "hung_task_check_count",
857 .data = &sysctl_hung_task_check_count,
90739081 858 .maxlen = sizeof(unsigned long),
82a1fcb9 859 .mode = 0644,
6d456111 860 .proc_handler = proc_doulongvec_minmax,
82a1fcb9
IM
861 },
862 {
82a1fcb9
IM
863 .procname = "hung_task_timeout_secs",
864 .data = &sysctl_hung_task_timeout_secs,
90739081 865 .maxlen = sizeof(unsigned long),
82a1fcb9 866 .mode = 0644,
6d456111 867 .proc_handler = proc_dohung_task_timeout_secs,
82a1fcb9
IM
868 },
869 {
82a1fcb9
IM
870 .procname = "hung_task_warnings",
871 .data = &sysctl_hung_task_warnings,
90739081 872 .maxlen = sizeof(unsigned long),
82a1fcb9 873 .mode = 0644,
6d456111 874 .proc_handler = proc_doulongvec_minmax,
82a1fcb9 875 },
c4f3b63f 876#endif
bebfa101
AK
877#ifdef CONFIG_COMPAT
878 {
bebfa101
AK
879 .procname = "compat-log",
880 .data = &compat_log,
881 .maxlen = sizeof (int),
882 .mode = 0644,
6d456111 883 .proc_handler = proc_dointvec,
bebfa101 884 },
951f22d5 885#endif
23f78d4a
IM
886#ifdef CONFIG_RT_MUTEXES
887 {
23f78d4a
IM
888 .procname = "max_lock_depth",
889 .data = &max_lock_depth,
890 .maxlen = sizeof(int),
891 .mode = 0644,
6d456111 892 .proc_handler = proc_dointvec,
23f78d4a 893 },
5096add8 894#endif
10a0a8d4 895 {
10a0a8d4
JF
896 .procname = "poweroff_cmd",
897 .data = &poweroff_cmd,
898 .maxlen = POWEROFF_CMD_PATH_LEN,
899 .mode = 0644,
6d456111 900 .proc_handler = proc_dostring,
10a0a8d4 901 },
0b77f5bf
DH
902#ifdef CONFIG_KEYS
903 {
0b77f5bf
DH
904 .procname = "keys",
905 .mode = 0555,
906 .child = key_sysctls,
907 },
908#endif
31a72bce
PM
909#ifdef CONFIG_RCU_TORTURE_TEST
910 {
31a72bce
PM
911 .procname = "rcutorture_runnable",
912 .data = &rcutorture_runnable,
913 .maxlen = sizeof(int),
914 .mode = 0644,
6d456111 915 .proc_handler = proc_dointvec,
31a72bce
PM
916 },
917#endif
cdd6c482 918#ifdef CONFIG_PERF_EVENTS
1ccd1549 919 {
cdd6c482
IM
920 .procname = "perf_event_paranoid",
921 .data = &sysctl_perf_event_paranoid,
922 .maxlen = sizeof(sysctl_perf_event_paranoid),
1ccd1549 923 .mode = 0644,
6d456111 924 .proc_handler = proc_dointvec,
1ccd1549 925 },
c5078f78 926 {
cdd6c482
IM
927 .procname = "perf_event_mlock_kb",
928 .data = &sysctl_perf_event_mlock,
929 .maxlen = sizeof(sysctl_perf_event_mlock),
c5078f78 930 .mode = 0644,
6d456111 931 .proc_handler = proc_dointvec,
c5078f78 932 },
a78ac325 933 {
cdd6c482
IM
934 .procname = "perf_event_max_sample_rate",
935 .data = &sysctl_perf_event_sample_rate,
936 .maxlen = sizeof(sysctl_perf_event_sample_rate),
a78ac325 937 .mode = 0644,
6d456111 938 .proc_handler = proc_dointvec,
a78ac325 939 },
1ccd1549 940#endif
dfec072e
VN
941#ifdef CONFIG_KMEMCHECK
942 {
dfec072e
VN
943 .procname = "kmemcheck",
944 .data = &kmemcheck_enabled,
945 .maxlen = sizeof(int),
946 .mode = 0644,
6d456111 947 .proc_handler = proc_dointvec,
dfec072e
VN
948 },
949#endif
cb684b5b 950#ifdef CONFIG_BLOCK
5e605b64 951 {
5e605b64
JA
952 .procname = "blk_iopoll",
953 .data = &blk_iopoll_enabled,
954 .maxlen = sizeof(int),
955 .mode = 0644,
6d456111 956 .proc_handler = proc_dointvec,
5e605b64 957 },
cb684b5b 958#endif
ed2c12f3
AM
959/*
960 * NOTE: do not add new entries to this table unless you have read
961 * Documentation/sysctl/ctl_unnumbered.txt
962 */
6fce56ec 963 { }
1da177e4
LT
964};
965
d8217f07 966static struct ctl_table vm_table[] = {
1da177e4 967 {
1da177e4
LT
968 .procname = "overcommit_memory",
969 .data = &sysctl_overcommit_memory,
970 .maxlen = sizeof(sysctl_overcommit_memory),
971 .mode = 0644,
6d456111 972 .proc_handler = proc_dointvec,
1da177e4 973 },
fadd8fbd 974 {
fadd8fbd
KH
975 .procname = "panic_on_oom",
976 .data = &sysctl_panic_on_oom,
977 .maxlen = sizeof(sysctl_panic_on_oom),
978 .mode = 0644,
6d456111 979 .proc_handler = proc_dointvec,
fadd8fbd 980 },
fe071d7e 981 {
fe071d7e
DR
982 .procname = "oom_kill_allocating_task",
983 .data = &sysctl_oom_kill_allocating_task,
984 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
985 .mode = 0644,
6d456111 986 .proc_handler = proc_dointvec,
fe071d7e 987 },
fef1bdd6 988 {
fef1bdd6
DR
989 .procname = "oom_dump_tasks",
990 .data = &sysctl_oom_dump_tasks,
991 .maxlen = sizeof(sysctl_oom_dump_tasks),
992 .mode = 0644,
6d456111 993 .proc_handler = proc_dointvec,
fef1bdd6 994 },
1da177e4 995 {
1da177e4
LT
996 .procname = "overcommit_ratio",
997 .data = &sysctl_overcommit_ratio,
998 .maxlen = sizeof(sysctl_overcommit_ratio),
999 .mode = 0644,
6d456111 1000 .proc_handler = proc_dointvec,
1da177e4
LT
1001 },
1002 {
1da177e4
LT
1003 .procname = "page-cluster",
1004 .data = &page_cluster,
1005 .maxlen = sizeof(int),
1006 .mode = 0644,
6d456111 1007 .proc_handler = proc_dointvec,
1da177e4
LT
1008 },
1009 {
1da177e4
LT
1010 .procname = "dirty_background_ratio",
1011 .data = &dirty_background_ratio,
1012 .maxlen = sizeof(dirty_background_ratio),
1013 .mode = 0644,
6d456111 1014 .proc_handler = dirty_background_ratio_handler,
1da177e4
LT
1015 .extra1 = &zero,
1016 .extra2 = &one_hundred,
1017 },
2da02997 1018 {
2da02997
DR
1019 .procname = "dirty_background_bytes",
1020 .data = &dirty_background_bytes,
1021 .maxlen = sizeof(dirty_background_bytes),
1022 .mode = 0644,
6d456111 1023 .proc_handler = dirty_background_bytes_handler,
fc3501d4 1024 .extra1 = &one_ul,
2da02997 1025 },
1da177e4 1026 {
1da177e4
LT
1027 .procname = "dirty_ratio",
1028 .data = &vm_dirty_ratio,
1029 .maxlen = sizeof(vm_dirty_ratio),
1030 .mode = 0644,
6d456111 1031 .proc_handler = dirty_ratio_handler,
1da177e4
LT
1032 .extra1 = &zero,
1033 .extra2 = &one_hundred,
1034 },
2da02997 1035 {
2da02997
DR
1036 .procname = "dirty_bytes",
1037 .data = &vm_dirty_bytes,
1038 .maxlen = sizeof(vm_dirty_bytes),
1039 .mode = 0644,
6d456111 1040 .proc_handler = dirty_bytes_handler,
9e4a5bda 1041 .extra1 = &dirty_bytes_min,
2da02997 1042 },
1da177e4 1043 {
1da177e4 1044 .procname = "dirty_writeback_centisecs",
f6ef9438
BS
1045 .data = &dirty_writeback_interval,
1046 .maxlen = sizeof(dirty_writeback_interval),
1da177e4 1047 .mode = 0644,
6d456111 1048 .proc_handler = dirty_writeback_centisecs_handler,
1da177e4
LT
1049 },
1050 {
1da177e4 1051 .procname = "dirty_expire_centisecs",
f6ef9438
BS
1052 .data = &dirty_expire_interval,
1053 .maxlen = sizeof(dirty_expire_interval),
1da177e4 1054 .mode = 0644,
6d456111 1055 .proc_handler = proc_dointvec,
1da177e4
LT
1056 },
1057 {
1da177e4
LT
1058 .procname = "nr_pdflush_threads",
1059 .data = &nr_pdflush_threads,
1060 .maxlen = sizeof nr_pdflush_threads,
1061 .mode = 0444 /* read-only*/,
6d456111 1062 .proc_handler = proc_dointvec,
1da177e4
LT
1063 },
1064 {
1da177e4
LT
1065 .procname = "swappiness",
1066 .data = &vm_swappiness,
1067 .maxlen = sizeof(vm_swappiness),
1068 .mode = 0644,
6d456111 1069 .proc_handler = proc_dointvec_minmax,
1da177e4
LT
1070 .extra1 = &zero,
1071 .extra2 = &one_hundred,
1072 },
1073#ifdef CONFIG_HUGETLB_PAGE
06808b08 1074 {
1da177e4 1075 .procname = "nr_hugepages",
e5ff2159 1076 .data = NULL,
1da177e4
LT
1077 .maxlen = sizeof(unsigned long),
1078 .mode = 0644,
6d456111 1079 .proc_handler = hugetlb_sysctl_handler,
1da177e4
LT
1080 .extra1 = (void *)&hugetlb_zero,
1081 .extra2 = (void *)&hugetlb_infinity,
06808b08
LS
1082 },
1083#ifdef CONFIG_NUMA
1084 {
1085 .procname = "nr_hugepages_mempolicy",
1086 .data = NULL,
1087 .maxlen = sizeof(unsigned long),
1088 .mode = 0644,
1089 .proc_handler = &hugetlb_mempolicy_sysctl_handler,
1090 .extra1 = (void *)&hugetlb_zero,
1091 .extra2 = (void *)&hugetlb_infinity,
1092 },
1093#endif
1da177e4 1094 {
1da177e4
LT
1095 .procname = "hugetlb_shm_group",
1096 .data = &sysctl_hugetlb_shm_group,
1097 .maxlen = sizeof(gid_t),
1098 .mode = 0644,
6d456111 1099 .proc_handler = proc_dointvec,
1da177e4 1100 },
396faf03 1101 {
396faf03
MG
1102 .procname = "hugepages_treat_as_movable",
1103 .data = &hugepages_treat_as_movable,
1104 .maxlen = sizeof(int),
1105 .mode = 0644,
6d456111 1106 .proc_handler = hugetlb_treat_movable_handler,
396faf03 1107 },
d1c3fb1f 1108 {
d1c3fb1f 1109 .procname = "nr_overcommit_hugepages",
e5ff2159
AK
1110 .data = NULL,
1111 .maxlen = sizeof(unsigned long),
d1c3fb1f 1112 .mode = 0644,
6d456111 1113 .proc_handler = hugetlb_overcommit_handler,
e5ff2159
AK
1114 .extra1 = (void *)&hugetlb_zero,
1115 .extra2 = (void *)&hugetlb_infinity,
d1c3fb1f 1116 },
1da177e4
LT
1117#endif
1118 {
1da177e4
LT
1119 .procname = "lowmem_reserve_ratio",
1120 .data = &sysctl_lowmem_reserve_ratio,
1121 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1122 .mode = 0644,
6d456111 1123 .proc_handler = lowmem_reserve_ratio_sysctl_handler,
1da177e4 1124 },
9d0243bc 1125 {
9d0243bc
AM
1126 .procname = "drop_caches",
1127 .data = &sysctl_drop_caches,
1128 .maxlen = sizeof(int),
1129 .mode = 0644,
1130 .proc_handler = drop_caches_sysctl_handler,
9d0243bc 1131 },
76ab0f53
MG
1132#ifdef CONFIG_COMPACTION
1133 {
1134 .procname = "compact_memory",
1135 .data = &sysctl_compact_memory,
1136 .maxlen = sizeof(int),
1137 .mode = 0200,
1138 .proc_handler = sysctl_compaction_handler,
1139 },
5e771905
MG
1140 {
1141 .procname = "extfrag_threshold",
1142 .data = &sysctl_extfrag_threshold,
1143 .maxlen = sizeof(int),
1144 .mode = 0644,
1145 .proc_handler = sysctl_extfrag_handler,
1146 .extra1 = &min_extfrag_threshold,
1147 .extra2 = &max_extfrag_threshold,
1148 },
1149
76ab0f53 1150#endif /* CONFIG_COMPACTION */
1da177e4 1151 {
1da177e4
LT
1152 .procname = "min_free_kbytes",
1153 .data = &min_free_kbytes,
1154 .maxlen = sizeof(min_free_kbytes),
1155 .mode = 0644,
6d456111 1156 .proc_handler = min_free_kbytes_sysctl_handler,
1da177e4
LT
1157 .extra1 = &zero,
1158 },
8ad4b1fb 1159 {
8ad4b1fb
RS
1160 .procname = "percpu_pagelist_fraction",
1161 .data = &percpu_pagelist_fraction,
1162 .maxlen = sizeof(percpu_pagelist_fraction),
1163 .mode = 0644,
6d456111 1164 .proc_handler = percpu_pagelist_fraction_sysctl_handler,
8ad4b1fb
RS
1165 .extra1 = &min_percpu_pagelist_fract,
1166 },
1da177e4
LT
1167#ifdef CONFIG_MMU
1168 {
1da177e4
LT
1169 .procname = "max_map_count",
1170 .data = &sysctl_max_map_count,
1171 .maxlen = sizeof(sysctl_max_map_count),
1172 .mode = 0644,
3e26120c 1173 .proc_handler = proc_dointvec_minmax,
70da2340 1174 .extra1 = &zero,
1da177e4 1175 },
dd8632a1
PM
1176#else
1177 {
dd8632a1
PM
1178 .procname = "nr_trim_pages",
1179 .data = &sysctl_nr_trim_pages,
1180 .maxlen = sizeof(sysctl_nr_trim_pages),
1181 .mode = 0644,
6d456111 1182 .proc_handler = proc_dointvec_minmax,
dd8632a1
PM
1183 .extra1 = &zero,
1184 },
1da177e4
LT
1185#endif
1186 {
1da177e4
LT
1187 .procname = "laptop_mode",
1188 .data = &laptop_mode,
1189 .maxlen = sizeof(laptop_mode),
1190 .mode = 0644,
6d456111 1191 .proc_handler = proc_dointvec_jiffies,
1da177e4
LT
1192 },
1193 {
1da177e4
LT
1194 .procname = "block_dump",
1195 .data = &block_dump,
1196 .maxlen = sizeof(block_dump),
1197 .mode = 0644,
6d456111 1198 .proc_handler = proc_dointvec,
1da177e4
LT
1199 .extra1 = &zero,
1200 },
1201 {
1da177e4
LT
1202 .procname = "vfs_cache_pressure",
1203 .data = &sysctl_vfs_cache_pressure,
1204 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1205 .mode = 0644,
6d456111 1206 .proc_handler = proc_dointvec,
1da177e4
LT
1207 .extra1 = &zero,
1208 },
1209#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1210 {
1da177e4
LT
1211 .procname = "legacy_va_layout",
1212 .data = &sysctl_legacy_va_layout,
1213 .maxlen = sizeof(sysctl_legacy_va_layout),
1214 .mode = 0644,
6d456111 1215 .proc_handler = proc_dointvec,
1da177e4
LT
1216 .extra1 = &zero,
1217 },
1218#endif
1743660b
CL
1219#ifdef CONFIG_NUMA
1220 {
1743660b
CL
1221 .procname = "zone_reclaim_mode",
1222 .data = &zone_reclaim_mode,
1223 .maxlen = sizeof(zone_reclaim_mode),
1224 .mode = 0644,
6d456111 1225 .proc_handler = proc_dointvec,
c84db23c 1226 .extra1 = &zero,
1743660b 1227 },
9614634f 1228 {
9614634f
CL
1229 .procname = "min_unmapped_ratio",
1230 .data = &sysctl_min_unmapped_ratio,
1231 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1232 .mode = 0644,
6d456111 1233 .proc_handler = sysctl_min_unmapped_ratio_sysctl_handler,
9614634f
CL
1234 .extra1 = &zero,
1235 .extra2 = &one_hundred,
1236 },
0ff38490 1237 {
0ff38490
CL
1238 .procname = "min_slab_ratio",
1239 .data = &sysctl_min_slab_ratio,
1240 .maxlen = sizeof(sysctl_min_slab_ratio),
1241 .mode = 0644,
6d456111 1242 .proc_handler = sysctl_min_slab_ratio_sysctl_handler,
0ff38490
CL
1243 .extra1 = &zero,
1244 .extra2 = &one_hundred,
1245 },
e6e5494c 1246#endif
77461ab3
CL
1247#ifdef CONFIG_SMP
1248 {
77461ab3
CL
1249 .procname = "stat_interval",
1250 .data = &sysctl_stat_interval,
1251 .maxlen = sizeof(sysctl_stat_interval),
1252 .mode = 0644,
6d456111 1253 .proc_handler = proc_dointvec_jiffies,
77461ab3
CL
1254 },
1255#endif
6e141546 1256#ifdef CONFIG_MMU
ed032189 1257 {
ed032189 1258 .procname = "mmap_min_addr",
788084ab
EP
1259 .data = &dac_mmap_min_addr,
1260 .maxlen = sizeof(unsigned long),
ed032189 1261 .mode = 0644,
6d456111 1262 .proc_handler = mmap_min_addr_handler,
ed032189 1263 },
6e141546 1264#endif
f0c0b2b8
KH
1265#ifdef CONFIG_NUMA
1266 {
f0c0b2b8
KH
1267 .procname = "numa_zonelist_order",
1268 .data = &numa_zonelist_order,
1269 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1270 .mode = 0644,
6d456111 1271 .proc_handler = numa_zonelist_order_handler,
f0c0b2b8
KH
1272 },
1273#endif
2b8232ce 1274#if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
5c36e657 1275 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
e6e5494c 1276 {
e6e5494c
IM
1277 .procname = "vdso_enabled",
1278 .data = &vdso_enabled,
1279 .maxlen = sizeof(vdso_enabled),
1280 .mode = 0644,
6d456111 1281 .proc_handler = proc_dointvec,
e6e5494c
IM
1282 .extra1 = &zero,
1283 },
1da177e4 1284#endif
195cf453
BG
1285#ifdef CONFIG_HIGHMEM
1286 {
195cf453
BG
1287 .procname = "highmem_is_dirtyable",
1288 .data = &vm_highmem_is_dirtyable,
1289 .maxlen = sizeof(vm_highmem_is_dirtyable),
1290 .mode = 0644,
6d456111 1291 .proc_handler = proc_dointvec_minmax,
195cf453
BG
1292 .extra1 = &zero,
1293 .extra2 = &one,
1294 },
1295#endif
4be6f6bb 1296 {
4be6f6bb
PZ
1297 .procname = "scan_unevictable_pages",
1298 .data = &scan_unevictable_pages,
1299 .maxlen = sizeof(scan_unevictable_pages),
1300 .mode = 0644,
6d456111 1301 .proc_handler = scan_unevictable_handler,
4be6f6bb 1302 },
6a46079c
AK
1303#ifdef CONFIG_MEMORY_FAILURE
1304 {
6a46079c
AK
1305 .procname = "memory_failure_early_kill",
1306 .data = &sysctl_memory_failure_early_kill,
1307 .maxlen = sizeof(sysctl_memory_failure_early_kill),
1308 .mode = 0644,
6d456111 1309 .proc_handler = proc_dointvec_minmax,
6a46079c
AK
1310 .extra1 = &zero,
1311 .extra2 = &one,
1312 },
1313 {
6a46079c
AK
1314 .procname = "memory_failure_recovery",
1315 .data = &sysctl_memory_failure_recovery,
1316 .maxlen = sizeof(sysctl_memory_failure_recovery),
1317 .mode = 0644,
6d456111 1318 .proc_handler = proc_dointvec_minmax,
6a46079c
AK
1319 .extra1 = &zero,
1320 .extra2 = &one,
1321 },
1322#endif
1323
2be7fe07
AM
1324/*
1325 * NOTE: do not add new entries to this table unless you have read
1326 * Documentation/sysctl/ctl_unnumbered.txt
1327 */
6fce56ec 1328 { }
1da177e4
LT
1329};
1330
2abc26fc 1331#if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
d8217f07 1332static struct ctl_table binfmt_misc_table[] = {
6fce56ec 1333 { }
2abc26fc
EB
1334};
1335#endif
1336
d8217f07 1337static struct ctl_table fs_table[] = {
1da177e4 1338 {
1da177e4
LT
1339 .procname = "inode-nr",
1340 .data = &inodes_stat,
1341 .maxlen = 2*sizeof(int),
1342 .mode = 0444,
6d456111 1343 .proc_handler = proc_dointvec,
1da177e4
LT
1344 },
1345 {
1da177e4
LT
1346 .procname = "inode-state",
1347 .data = &inodes_stat,
1348 .maxlen = 7*sizeof(int),
1349 .mode = 0444,
6d456111 1350 .proc_handler = proc_dointvec,
1da177e4
LT
1351 },
1352 {
1da177e4
LT
1353 .procname = "file-nr",
1354 .data = &files_stat,
1355 .maxlen = 3*sizeof(int),
1356 .mode = 0444,
6d456111 1357 .proc_handler = proc_nr_files,
1da177e4
LT
1358 },
1359 {
1da177e4
LT
1360 .procname = "file-max",
1361 .data = &files_stat.max_files,
1362 .maxlen = sizeof(int),
1363 .mode = 0644,
6d456111 1364 .proc_handler = proc_dointvec,
1da177e4 1365 },
9cfe015a 1366 {
9cfe015a
ED
1367 .procname = "nr_open",
1368 .data = &sysctl_nr_open,
1369 .maxlen = sizeof(int),
1370 .mode = 0644,
6d456111 1371 .proc_handler = proc_dointvec_minmax,
eceea0b3
AV
1372 .extra1 = &sysctl_nr_open_min,
1373 .extra2 = &sysctl_nr_open_max,
9cfe015a 1374 },
1da177e4 1375 {
1da177e4
LT
1376 .procname = "dentry-state",
1377 .data = &dentry_stat,
1378 .maxlen = 6*sizeof(int),
1379 .mode = 0444,
6d456111 1380 .proc_handler = proc_dointvec,
1da177e4
LT
1381 },
1382 {
1da177e4
LT
1383 .procname = "overflowuid",
1384 .data = &fs_overflowuid,
1385 .maxlen = sizeof(int),
1386 .mode = 0644,
6d456111 1387 .proc_handler = proc_dointvec_minmax,
1da177e4
LT
1388 .extra1 = &minolduid,
1389 .extra2 = &maxolduid,
1390 },
1391 {
1da177e4
LT
1392 .procname = "overflowgid",
1393 .data = &fs_overflowgid,
1394 .maxlen = sizeof(int),
1395 .mode = 0644,
6d456111 1396 .proc_handler = proc_dointvec_minmax,
1da177e4
LT
1397 .extra1 = &minolduid,
1398 .extra2 = &maxolduid,
1399 },
bfcd17a6 1400#ifdef CONFIG_FILE_LOCKING
1da177e4 1401 {
1da177e4
LT
1402 .procname = "leases-enable",
1403 .data = &leases_enable,
1404 .maxlen = sizeof(int),
1405 .mode = 0644,
6d456111 1406 .proc_handler = proc_dointvec,
1da177e4 1407 },
bfcd17a6 1408#endif
1da177e4
LT
1409#ifdef CONFIG_DNOTIFY
1410 {
1da177e4
LT
1411 .procname = "dir-notify-enable",
1412 .data = &dir_notify_enable,
1413 .maxlen = sizeof(int),
1414 .mode = 0644,
6d456111 1415 .proc_handler = proc_dointvec,
1da177e4
LT
1416 },
1417#endif
1418#ifdef CONFIG_MMU
bfcd17a6 1419#ifdef CONFIG_FILE_LOCKING
1da177e4 1420 {
1da177e4
LT
1421 .procname = "lease-break-time",
1422 .data = &lease_break_time,
1423 .maxlen = sizeof(int),
1424 .mode = 0644,
6d456111 1425 .proc_handler = proc_dointvec,
1da177e4 1426 },
bfcd17a6 1427#endif
ebf3f09c 1428#ifdef CONFIG_AIO
1da177e4 1429 {
1da177e4
LT
1430 .procname = "aio-nr",
1431 .data = &aio_nr,
1432 .maxlen = sizeof(aio_nr),
1433 .mode = 0444,
6d456111 1434 .proc_handler = proc_doulongvec_minmax,
1da177e4
LT
1435 },
1436 {
1da177e4
LT
1437 .procname = "aio-max-nr",
1438 .data = &aio_max_nr,
1439 .maxlen = sizeof(aio_max_nr),
1440 .mode = 0644,
6d456111 1441 .proc_handler = proc_doulongvec_minmax,
1da177e4 1442 },
ebf3f09c 1443#endif /* CONFIG_AIO */
2d9048e2 1444#ifdef CONFIG_INOTIFY_USER
0399cb08 1445 {
0399cb08
RL
1446 .procname = "inotify",
1447 .mode = 0555,
1448 .child = inotify_table,
1449 },
1450#endif
7ef9964e
DL
1451#ifdef CONFIG_EPOLL
1452 {
1453 .procname = "epoll",
1454 .mode = 0555,
1455 .child = epoll_table,
1456 },
1457#endif
1da177e4 1458#endif
d6e71144 1459 {
d6e71144
AC
1460 .procname = "suid_dumpable",
1461 .data = &suid_dumpable,
1462 .maxlen = sizeof(int),
1463 .mode = 0644,
6d456111 1464 .proc_handler = proc_dointvec_minmax,
8e654fba
MW
1465 .extra1 = &zero,
1466 .extra2 = &two,
d6e71144 1467 },
2abc26fc
EB
1468#if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1469 {
2abc26fc
EB
1470 .procname = "binfmt_misc",
1471 .mode = 0555,
1472 .child = binfmt_misc_table,
1473 },
1474#endif
b492e95b 1475 {
ff9da691
JA
1476 .procname = "pipe-max-size",
1477 .data = &pipe_max_size,
b492e95b
JA
1478 .maxlen = sizeof(int),
1479 .mode = 0644,
ff9da691
JA
1480 .proc_handler = &pipe_proc_fn,
1481 .extra1 = &pipe_min_size,
b492e95b 1482 },
2be7fe07
AM
1483/*
1484 * NOTE: do not add new entries to this table unless you have read
1485 * Documentation/sysctl/ctl_unnumbered.txt
2be7fe07 1486 */
6fce56ec 1487 { }
1da177e4
LT
1488};
1489
d8217f07 1490static struct ctl_table debug_table[] = {
ab3c68ee
HC
1491#if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_SPARC) || \
1492 defined(CONFIG_S390)
abd4f750 1493 {
abd4f750
MAS
1494 .procname = "exception-trace",
1495 .data = &show_unhandled_signals,
1496 .maxlen = sizeof(int),
1497 .mode = 0644,
1498 .proc_handler = proc_dointvec
1499 },
b2be84df
MH
1500#endif
1501#if defined(CONFIG_OPTPROBES)
1502 {
1503 .procname = "kprobes-optimization",
1504 .data = &sysctl_kprobes_optimization,
1505 .maxlen = sizeof(int),
1506 .mode = 0644,
1507 .proc_handler = proc_kprobes_optimization_handler,
1508 .extra1 = &zero,
1509 .extra2 = &one,
1510 },
abd4f750 1511#endif
6fce56ec 1512 { }
1da177e4
LT
1513};
1514
d8217f07 1515static struct ctl_table dev_table[] = {
6fce56ec 1516 { }
0eeca283 1517};
1da177e4 1518
330d57fb
AV
1519static DEFINE_SPINLOCK(sysctl_lock);
1520
1521/* called under sysctl_lock */
1522static int use_table(struct ctl_table_header *p)
1523{
1524 if (unlikely(p->unregistering))
1525 return 0;
1526 p->used++;
1527 return 1;
1528}
1529
1530/* called under sysctl_lock */
1531static void unuse_table(struct ctl_table_header *p)
1532{
1533 if (!--p->used)
1534 if (unlikely(p->unregistering))
1535 complete(p->unregistering);
1536}
1537
1538/* called under sysctl_lock, will reacquire if has to wait */
1539static void start_unregistering(struct ctl_table_header *p)
1540{
1541 /*
1542 * if p->used is 0, nobody will ever touch that entry again;
1543 * we'll eliminate all paths to it before dropping sysctl_lock
1544 */
1545 if (unlikely(p->used)) {
1546 struct completion wait;
1547 init_completion(&wait);
1548 p->unregistering = &wait;
1549 spin_unlock(&sysctl_lock);
1550 wait_for_completion(&wait);
1551 spin_lock(&sysctl_lock);
f7e6ced4
AV
1552 } else {
1553 /* anything non-NULL; we'll never dereference it */
1554 p->unregistering = ERR_PTR(-EINVAL);
330d57fb
AV
1555 }
1556 /*
1557 * do not remove from the list until nobody holds it; walking the
1558 * list in do_sysctl() relies on that.
1559 */
1560 list_del_init(&p->ctl_entry);
1561}
1562
f7e6ced4
AV
1563void sysctl_head_get(struct ctl_table_header *head)
1564{
1565 spin_lock(&sysctl_lock);
1566 head->count++;
1567 spin_unlock(&sysctl_lock);
1568}
1569
1570void sysctl_head_put(struct ctl_table_header *head)
1571{
1572 spin_lock(&sysctl_lock);
1573 if (!--head->count)
1574 kfree(head);
1575 spin_unlock(&sysctl_lock);
1576}
1577
1578struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1579{
1580 if (!head)
1581 BUG();
1582 spin_lock(&sysctl_lock);
1583 if (!use_table(head))
1584 head = ERR_PTR(-ENOENT);
1585 spin_unlock(&sysctl_lock);
1586 return head;
1587}
1588
805b5d5e
EB
1589void sysctl_head_finish(struct ctl_table_header *head)
1590{
1591 if (!head)
1592 return;
1593 spin_lock(&sysctl_lock);
1594 unuse_table(head);
1595 spin_unlock(&sysctl_lock);
1596}
1597
73455092
AV
1598static struct ctl_table_set *
1599lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1600{
1601 struct ctl_table_set *set = &root->default_set;
1602 if (root->lookup)
1603 set = root->lookup(root, namespaces);
1604 return set;
1605}
1606
e51b6ba0
EB
1607static struct list_head *
1608lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
805b5d5e 1609{
73455092
AV
1610 struct ctl_table_set *set = lookup_header_set(root, namespaces);
1611 return &set->list;
e51b6ba0
EB
1612}
1613
1614struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1615 struct ctl_table_header *prev)
1616{
1617 struct ctl_table_root *root;
1618 struct list_head *header_list;
805b5d5e
EB
1619 struct ctl_table_header *head;
1620 struct list_head *tmp;
e51b6ba0 1621
805b5d5e
EB
1622 spin_lock(&sysctl_lock);
1623 if (prev) {
e51b6ba0 1624 head = prev;
805b5d5e
EB
1625 tmp = &prev->ctl_entry;
1626 unuse_table(prev);
1627 goto next;
1628 }
1629 tmp = &root_table_header.ctl_entry;
1630 for (;;) {
1631 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1632
1633 if (!use_table(head))
1634 goto next;
1635 spin_unlock(&sysctl_lock);
1636 return head;
1637 next:
e51b6ba0 1638 root = head->root;
805b5d5e 1639 tmp = tmp->next;
e51b6ba0
EB
1640 header_list = lookup_header_list(root, namespaces);
1641 if (tmp != header_list)
1642 continue;
1643
1644 do {
1645 root = list_entry(root->root_list.next,
1646 struct ctl_table_root, root_list);
1647 if (root == &sysctl_table_root)
1648 goto out;
1649 header_list = lookup_header_list(root, namespaces);
1650 } while (list_empty(header_list));
1651 tmp = header_list->next;
805b5d5e 1652 }
e51b6ba0 1653out:
805b5d5e
EB
1654 spin_unlock(&sysctl_lock);
1655 return NULL;
1656}
1657
e51b6ba0
EB
1658struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1659{
1660 return __sysctl_head_next(current->nsproxy, prev);
1661}
1662
1663void register_sysctl_root(struct ctl_table_root *root)
1664{
1665 spin_lock(&sysctl_lock);
1666 list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1667 spin_unlock(&sysctl_lock);
1668}
1669
1da177e4 1670/*
1ff007eb 1671 * sysctl_perm does NOT grant the superuser all rights automatically, because
1da177e4
LT
1672 * some sysctl variables are readonly even to root.
1673 */
1674
1675static int test_perm(int mode, int op)
1676{
76aac0e9 1677 if (!current_euid())
1da177e4
LT
1678 mode >>= 6;
1679 else if (in_egroup_p(0))
1680 mode >>= 3;
e6305c43 1681 if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1da177e4
LT
1682 return 0;
1683 return -EACCES;
1684}
1685
d7321cd6 1686int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1da177e4
LT
1687{
1688 int error;
d7321cd6
PE
1689 int mode;
1690
e6305c43 1691 error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1da177e4
LT
1692 if (error)
1693 return error;
d7321cd6
PE
1694
1695 if (root->permissions)
1696 mode = root->permissions(root, current->nsproxy, table);
1697 else
1698 mode = table->mode;
1699
1700 return test_perm(mode, op);
1da177e4
LT
1701}
1702
d912b0cc
EB
1703static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1704{
2315ffa0 1705 for (; table->procname; table++) {
d912b0cc
EB
1706 table->parent = parent;
1707 if (table->child)
1708 sysctl_set_parent(table, table->child);
1709 }
1710}
1711
1712static __init int sysctl_init(void)
1713{
1714 sysctl_set_parent(NULL, root_table);
88f458e4
HS
1715#ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1716 {
1717 int err;
1718 err = sysctl_check_table(current->nsproxy, root_table);
1719 }
1720#endif
d912b0cc
EB
1721 return 0;
1722}
1723
1724core_initcall(sysctl_init);
1725
bfbcf034
AV
1726static struct ctl_table *is_branch_in(struct ctl_table *branch,
1727 struct ctl_table *table)
ae7edecc
AV
1728{
1729 struct ctl_table *p;
1730 const char *s = branch->procname;
1731
1732 /* branch should have named subdirectory as its first element */
1733 if (!s || !branch->child)
bfbcf034 1734 return NULL;
ae7edecc
AV
1735
1736 /* ... and nothing else */
2315ffa0 1737 if (branch[1].procname)
bfbcf034 1738 return NULL;
ae7edecc
AV
1739
1740 /* table should contain subdirectory with the same name */
2315ffa0 1741 for (p = table; p->procname; p++) {
ae7edecc
AV
1742 if (!p->child)
1743 continue;
1744 if (p->procname && strcmp(p->procname, s) == 0)
bfbcf034 1745 return p;
ae7edecc 1746 }
bfbcf034 1747 return NULL;
ae7edecc
AV
1748}
1749
1750/* see if attaching q to p would be an improvement */
1751static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1752{
1753 struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
bfbcf034 1754 struct ctl_table *next;
ae7edecc
AV
1755 int is_better = 0;
1756 int not_in_parent = !p->attached_by;
1757
bfbcf034 1758 while ((next = is_branch_in(by, to)) != NULL) {
ae7edecc
AV
1759 if (by == q->attached_by)
1760 is_better = 1;
1761 if (to == p->attached_by)
1762 not_in_parent = 1;
1763 by = by->child;
bfbcf034 1764 to = next->child;
ae7edecc
AV
1765 }
1766
1767 if (is_better && not_in_parent) {
1768 q->attached_by = by;
1769 q->attached_to = to;
1770 q->parent = p;
1771 }
1772}
1773
1da177e4 1774/**
e51b6ba0
EB
1775 * __register_sysctl_paths - register a sysctl hierarchy
1776 * @root: List of sysctl headers to register on
1777 * @namespaces: Data to compute which lists of sysctl entries are visible
29e796fd 1778 * @path: The path to the directory the sysctl table is in.
1da177e4 1779 * @table: the top-level table structure
1da177e4
LT
1780 *
1781 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
29e796fd 1782 * array. A completely 0 filled entry terminates the table.
1da177e4 1783 *
d8217f07 1784 * The members of the &struct ctl_table structure are used as follows:
1da177e4 1785 *
1da177e4
LT
1786 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1787 * enter a sysctl file
1788 *
1789 * data - a pointer to data for use by proc_handler
1790 *
1791 * maxlen - the maximum size in bytes of the data
1792 *
1793 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1794 *
1795 * child - a pointer to the child sysctl table if this entry is a directory, or
1796 * %NULL.
1797 *
1798 * proc_handler - the text handler routine (described below)
1799 *
1da177e4
LT
1800 * de - for internal use by the sysctl routines
1801 *
1802 * extra1, extra2 - extra pointers usable by the proc handler routines
1803 *
1804 * Leaf nodes in the sysctl tree will be represented by a single file
1805 * under /proc; non-leaf nodes will be represented by directories.
1806 *
1807 * sysctl(2) can automatically manage read and write requests through
1808 * the sysctl table. The data and maxlen fields of the ctl_table
1809 * struct enable minimal validation of the values being written to be
1810 * performed, and the mode field allows minimal authentication.
1811 *
1da177e4
LT
1812 * There must be a proc_handler routine for any terminal nodes
1813 * mirrored under /proc/sys (non-terminals are handled by a built-in
1814 * directory handler). Several default handlers are available to
1815 * cover common cases -
1816 *
1817 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1818 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1819 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1820 *
1821 * It is the handler's job to read the input buffer from user memory
1822 * and process it. The handler should return 0 on success.
1823 *
1824 * This routine returns %NULL on a failure to register, and a pointer
1825 * to the table header on success.
1826 */
e51b6ba0
EB
1827struct ctl_table_header *__register_sysctl_paths(
1828 struct ctl_table_root *root,
1829 struct nsproxy *namespaces,
1830 const struct ctl_path *path, struct ctl_table *table)
1da177e4 1831{
29e796fd
EB
1832 struct ctl_table_header *header;
1833 struct ctl_table *new, **prevp;
1834 unsigned int n, npath;
ae7edecc 1835 struct ctl_table_set *set;
29e796fd
EB
1836
1837 /* Count the path components */
2315ffa0 1838 for (npath = 0; path[npath].procname; ++npath)
29e796fd
EB
1839 ;
1840
1841 /*
1842 * For each path component, allocate a 2-element ctl_table array.
1843 * The first array element will be filled with the sysctl entry
2315ffa0 1844 * for this, the second will be the sentinel (procname == 0).
29e796fd
EB
1845 *
1846 * We allocate everything in one go so that we don't have to
1847 * worry about freeing additional memory in unregister_sysctl_table.
1848 */
1849 header = kzalloc(sizeof(struct ctl_table_header) +
1850 (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
1851 if (!header)
1da177e4 1852 return NULL;
29e796fd
EB
1853
1854 new = (struct ctl_table *) (header + 1);
1855
1856 /* Now connect the dots */
1857 prevp = &header->ctl_table;
1858 for (n = 0; n < npath; ++n, ++path) {
1859 /* Copy the procname */
1860 new->procname = path->procname;
29e796fd
EB
1861 new->mode = 0555;
1862
1863 *prevp = new;
1864 prevp = &new->child;
1865
1866 new += 2;
1867 }
1868 *prevp = table;
23eb06de 1869 header->ctl_table_arg = table;
29e796fd
EB
1870
1871 INIT_LIST_HEAD(&header->ctl_entry);
1872 header->used = 0;
1873 header->unregistering = NULL;
e51b6ba0 1874 header->root = root;
29e796fd 1875 sysctl_set_parent(NULL, header->ctl_table);
f7e6ced4 1876 header->count = 1;
88f458e4 1877#ifdef CONFIG_SYSCTL_SYSCALL_CHECK
e51b6ba0 1878 if (sysctl_check_table(namespaces, header->ctl_table)) {
29e796fd 1879 kfree(header);
fc6cd25b
EB
1880 return NULL;
1881 }
88f458e4 1882#endif
330d57fb 1883 spin_lock(&sysctl_lock);
73455092 1884 header->set = lookup_header_set(root, namespaces);
ae7edecc
AV
1885 header->attached_by = header->ctl_table;
1886 header->attached_to = root_table;
1887 header->parent = &root_table_header;
1888 for (set = header->set; set; set = set->parent) {
1889 struct ctl_table_header *p;
1890 list_for_each_entry(p, &set->list, ctl_entry) {
1891 if (p->unregistering)
1892 continue;
1893 try_attach(p, header);
1894 }
1895 }
1896 header->parent->count++;
73455092 1897 list_add_tail(&header->ctl_entry, &header->set->list);
330d57fb 1898 spin_unlock(&sysctl_lock);
29e796fd
EB
1899
1900 return header;
1901}
1902
e51b6ba0
EB
1903/**
1904 * register_sysctl_table_path - register a sysctl table hierarchy
1905 * @path: The path to the directory the sysctl table is in.
1906 * @table: the top-level table structure
1907 *
1908 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1909 * array. A completely 0 filled entry terminates the table.
1910 *
1911 * See __register_sysctl_paths for more details.
1912 */
1913struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1914 struct ctl_table *table)
1915{
1916 return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
1917 path, table);
1918}
1919
29e796fd
EB
1920/**
1921 * register_sysctl_table - register a sysctl table hierarchy
1922 * @table: the top-level table structure
1923 *
1924 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1925 * array. A completely 0 filled entry terminates the table.
1926 *
1927 * See register_sysctl_paths for more details.
1928 */
1929struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
1930{
1931 static const struct ctl_path null_path[] = { {} };
1932
1933 return register_sysctl_paths(null_path, table);
1da177e4
LT
1934}
1935
1936/**
1937 * unregister_sysctl_table - unregister a sysctl table hierarchy
1938 * @header: the header returned from register_sysctl_table
1939 *
1940 * Unregisters the sysctl table and all children. proc entries may not
1941 * actually be removed until they are no longer used by anyone.
1942 */
1943void unregister_sysctl_table(struct ctl_table_header * header)
1944{
330d57fb 1945 might_sleep();
f1dad166
PE
1946
1947 if (header == NULL)
1948 return;
1949
330d57fb
AV
1950 spin_lock(&sysctl_lock);
1951 start_unregistering(header);
ae7edecc
AV
1952 if (!--header->parent->count) {
1953 WARN_ON(1);
1954 kfree(header->parent);
1955 }
f7e6ced4
AV
1956 if (!--header->count)
1957 kfree(header);
330d57fb 1958 spin_unlock(&sysctl_lock);
1da177e4
LT
1959}
1960
9043476f
AV
1961int sysctl_is_seen(struct ctl_table_header *p)
1962{
1963 struct ctl_table_set *set = p->set;
1964 int res;
1965 spin_lock(&sysctl_lock);
1966 if (p->unregistering)
1967 res = 0;
1968 else if (!set->is_seen)
1969 res = 1;
1970 else
1971 res = set->is_seen(set);
1972 spin_unlock(&sysctl_lock);
1973 return res;
1974}
1975
73455092
AV
1976void setup_sysctl_set(struct ctl_table_set *p,
1977 struct ctl_table_set *parent,
1978 int (*is_seen)(struct ctl_table_set *))
1979{
1980 INIT_LIST_HEAD(&p->list);
1981 p->parent = parent ? parent : &sysctl_table_root.default_set;
1982 p->is_seen = is_seen;
1983}
1984
b89a8171 1985#else /* !CONFIG_SYSCTL */
d8217f07 1986struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
b89a8171
EB
1987{
1988 return NULL;
1989}
1990
29e796fd
EB
1991struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1992 struct ctl_table *table)
1993{
1994 return NULL;
1995}
1996
b89a8171
EB
1997void unregister_sysctl_table(struct ctl_table_header * table)
1998{
1999}
2000
73455092
AV
2001void setup_sysctl_set(struct ctl_table_set *p,
2002 struct ctl_table_set *parent,
2003 int (*is_seen)(struct ctl_table_set *))
2004{
2005}
2006
f7e6ced4
AV
2007void sysctl_head_put(struct ctl_table_header *head)
2008{
2009}
2010
b89a8171
EB
2011#endif /* CONFIG_SYSCTL */
2012
1da177e4
LT
2013/*
2014 * /proc/sys support
2015 */
2016
b89a8171 2017#ifdef CONFIG_PROC_SYSCTL
1da177e4 2018
b1ba4ddd 2019static int _proc_do_string(void* data, int maxlen, int write,
8d65af78 2020 void __user *buffer,
b1ba4ddd 2021 size_t *lenp, loff_t *ppos)
1da177e4
LT
2022{
2023 size_t len;
2024 char __user *p;
2025 char c;
8d060877
ON
2026
2027 if (!data || !maxlen || !*lenp) {
1da177e4
LT
2028 *lenp = 0;
2029 return 0;
2030 }
8d060877 2031
1da177e4
LT
2032 if (write) {
2033 len = 0;
2034 p = buffer;
2035 while (len < *lenp) {
2036 if (get_user(c, p++))
2037 return -EFAULT;
2038 if (c == 0 || c == '\n')
2039 break;
2040 len++;
2041 }
f5dd3d6f
SV
2042 if (len >= maxlen)
2043 len = maxlen-1;
2044 if(copy_from_user(data, buffer, len))
1da177e4 2045 return -EFAULT;
f5dd3d6f 2046 ((char *) data)[len] = 0;
1da177e4
LT
2047 *ppos += *lenp;
2048 } else {
f5dd3d6f
SV
2049 len = strlen(data);
2050 if (len > maxlen)
2051 len = maxlen;
8d060877
ON
2052
2053 if (*ppos > len) {
2054 *lenp = 0;
2055 return 0;
2056 }
2057
2058 data += *ppos;
2059 len -= *ppos;
2060
1da177e4
LT
2061 if (len > *lenp)
2062 len = *lenp;
2063 if (len)
f5dd3d6f 2064 if(copy_to_user(buffer, data, len))
1da177e4
LT
2065 return -EFAULT;
2066 if (len < *lenp) {
2067 if(put_user('\n', ((char __user *) buffer) + len))
2068 return -EFAULT;
2069 len++;
2070 }
2071 *lenp = len;
2072 *ppos += len;
2073 }
2074 return 0;
2075}
2076
f5dd3d6f
SV
2077/**
2078 * proc_dostring - read a string sysctl
2079 * @table: the sysctl table
2080 * @write: %TRUE if this is a write to the sysctl file
f5dd3d6f
SV
2081 * @buffer: the user buffer
2082 * @lenp: the size of the user buffer
2083 * @ppos: file position
2084 *
2085 * Reads/writes a string from/to the user buffer. If the kernel
2086 * buffer provided is not large enough to hold the string, the
2087 * string is truncated. The copied string is %NULL-terminated.
2088 * If the string is being read by the user process, it is copied
2089 * and a newline '\n' is added. It is truncated if the buffer is
2090 * not large enough.
2091 *
2092 * Returns 0 on success.
2093 */
8d65af78 2094int proc_dostring(struct ctl_table *table, int write,
f5dd3d6f
SV
2095 void __user *buffer, size_t *lenp, loff_t *ppos)
2096{
8d65af78 2097 return _proc_do_string(table->data, table->maxlen, write,
f5dd3d6f
SV
2098 buffer, lenp, ppos);
2099}
2100
00b7c339
AW
2101static size_t proc_skip_spaces(char **buf)
2102{
2103 size_t ret;
2104 char *tmp = skip_spaces(*buf);
2105 ret = tmp - *buf;
2106 *buf = tmp;
2107 return ret;
2108}
2109
9f977fb7
OP
2110static void proc_skip_char(char **buf, size_t *size, const char v)
2111{
2112 while (*size) {
2113 if (**buf != v)
2114 break;
2115 (*size)--;
2116 (*buf)++;
2117 }
2118}
2119
00b7c339
AW
2120#define TMPBUFLEN 22
2121/**
0fc377bd 2122 * proc_get_long - reads an ASCII formatted integer from a user buffer
00b7c339 2123 *
0fc377bd
RD
2124 * @buf: a kernel buffer
2125 * @size: size of the kernel buffer
2126 * @val: this is where the number will be stored
2127 * @neg: set to %TRUE if number is negative
2128 * @perm_tr: a vector which contains the allowed trailers
2129 * @perm_tr_len: size of the perm_tr vector
2130 * @tr: pointer to store the trailer character
00b7c339 2131 *
0fc377bd
RD
2132 * In case of success %0 is returned and @buf and @size are updated with
2133 * the amount of bytes read. If @tr is non-NULL and a trailing
2134 * character exists (size is non-zero after returning from this
2135 * function), @tr is updated with the trailing character.
00b7c339
AW
2136 */
2137static int proc_get_long(char **buf, size_t *size,
2138 unsigned long *val, bool *neg,
2139 const char *perm_tr, unsigned perm_tr_len, char *tr)
2140{
2141 int len;
2142 char *p, tmp[TMPBUFLEN];
2143
2144 if (!*size)
2145 return -EINVAL;
2146
2147 len = *size;
2148 if (len > TMPBUFLEN - 1)
2149 len = TMPBUFLEN - 1;
2150
2151 memcpy(tmp, *buf, len);
2152
2153 tmp[len] = 0;
2154 p = tmp;
2155 if (*p == '-' && *size > 1) {
2156 *neg = true;
2157 p++;
2158 } else
2159 *neg = false;
2160 if (!isdigit(*p))
2161 return -EINVAL;
2162
2163 *val = simple_strtoul(p, &p, 0);
2164
2165 len = p - tmp;
2166
2167 /* We don't know if the next char is whitespace thus we may accept
2168 * invalid integers (e.g. 1234...a) or two integers instead of one
2169 * (e.g. 123...1). So lets not allow such large numbers. */
2170 if (len == TMPBUFLEN - 1)
2171 return -EINVAL;
2172
2173 if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
2174 return -EINVAL;
1da177e4 2175
00b7c339
AW
2176 if (tr && (len < *size))
2177 *tr = *p;
2178
2179 *buf += len;
2180 *size -= len;
2181
2182 return 0;
2183}
2184
2185/**
0fc377bd 2186 * proc_put_long - converts an integer to a decimal ASCII formatted string
00b7c339 2187 *
0fc377bd
RD
2188 * @buf: the user buffer
2189 * @size: the size of the user buffer
2190 * @val: the integer to be converted
2191 * @neg: sign of the number, %TRUE for negative
00b7c339 2192 *
0fc377bd
RD
2193 * In case of success %0 is returned and @buf and @size are updated with
2194 * the amount of bytes written.
00b7c339
AW
2195 */
2196static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2197 bool neg)
2198{
2199 int len;
2200 char tmp[TMPBUFLEN], *p = tmp;
2201
2202 sprintf(p, "%s%lu", neg ? "-" : "", val);
2203 len = strlen(tmp);
2204 if (len > *size)
2205 len = *size;
2206 if (copy_to_user(*buf, tmp, len))
2207 return -EFAULT;
2208 *size -= len;
2209 *buf += len;
2210 return 0;
2211}
2212#undef TMPBUFLEN
2213
2214static int proc_put_char(void __user **buf, size_t *size, char c)
2215{
2216 if (*size) {
2217 char __user **buffer = (char __user **)buf;
2218 if (put_user(c, *buffer))
2219 return -EFAULT;
2220 (*size)--, (*buffer)++;
2221 *buf = *buffer;
2222 }
2223 return 0;
2224}
1da177e4 2225
00b7c339 2226static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
1da177e4
LT
2227 int *valp,
2228 int write, void *data)
2229{
2230 if (write) {
2231 *valp = *negp ? -*lvalp : *lvalp;
2232 } else {
2233 int val = *valp;
2234 if (val < 0) {
00b7c339 2235 *negp = true;
1da177e4
LT
2236 *lvalp = (unsigned long)-val;
2237 } else {
00b7c339 2238 *negp = false;
1da177e4
LT
2239 *lvalp = (unsigned long)val;
2240 }
2241 }
2242 return 0;
2243}
2244
00b7c339
AW
2245static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2246
d8217f07 2247static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
8d65af78 2248 int write, void __user *buffer,
fcfbd547 2249 size_t *lenp, loff_t *ppos,
00b7c339 2250 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
1da177e4
LT
2251 int write, void *data),
2252 void *data)
2253{
00b7c339
AW
2254 int *i, vleft, first = 1, err = 0;
2255 unsigned long page = 0;
2256 size_t left;
2257 char *kbuf;
1da177e4 2258
00b7c339 2259 if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
1da177e4
LT
2260 *lenp = 0;
2261 return 0;
2262 }
2263
fcfbd547 2264 i = (int *) tbl_data;
1da177e4
LT
2265 vleft = table->maxlen / sizeof(*i);
2266 left = *lenp;
2267
2268 if (!conv)
2269 conv = do_proc_dointvec_conv;
2270
00b7c339
AW
2271 if (write) {
2272 if (left > PAGE_SIZE - 1)
2273 left = PAGE_SIZE - 1;
2274 page = __get_free_page(GFP_TEMPORARY);
2275 kbuf = (char *) page;
2276 if (!kbuf)
2277 return -ENOMEM;
2278 if (copy_from_user(kbuf, buffer, left)) {
2279 err = -EFAULT;
2280 goto free;
2281 }
2282 kbuf[left] = 0;
2283 }
2284
1da177e4 2285 for (; left && vleft--; i++, first=0) {
00b7c339
AW
2286 unsigned long lval;
2287 bool neg;
1da177e4 2288
00b7c339
AW
2289 if (write) {
2290 left -= proc_skip_spaces(&kbuf);
1da177e4 2291
563b0467
O
2292 if (!left)
2293 break;
00b7c339
AW
2294 err = proc_get_long(&kbuf, &left, &lval, &neg,
2295 proc_wspace_sep,
2296 sizeof(proc_wspace_sep), NULL);
2297 if (err)
1da177e4 2298 break;
00b7c339
AW
2299 if (conv(&neg, &lval, i, 1, data)) {
2300 err = -EINVAL;
1da177e4 2301 break;
00b7c339 2302 }
1da177e4 2303 } else {
00b7c339
AW
2304 if (conv(&neg, &lval, i, 0, data)) {
2305 err = -EINVAL;
2306 break;
2307 }
1da177e4 2308 if (!first)
00b7c339
AW
2309 err = proc_put_char(&buffer, &left, '\t');
2310 if (err)
2311 break;
2312 err = proc_put_long(&buffer, &left, lval, neg);
2313 if (err)
1da177e4 2314 break;
1da177e4
LT
2315 }
2316 }
2317
00b7c339
AW
2318 if (!write && !first && left && !err)
2319 err = proc_put_char(&buffer, &left, '\n');
563b0467 2320 if (write && !err && left)
00b7c339
AW
2321 left -= proc_skip_spaces(&kbuf);
2322free:
1da177e4 2323 if (write) {
00b7c339
AW
2324 free_page(page);
2325 if (first)
2326 return err ? : -EINVAL;
1da177e4 2327 }
1da177e4
LT
2328 *lenp -= left;
2329 *ppos += *lenp;
00b7c339 2330 return err;
1da177e4
LT
2331}
2332
8d65af78 2333static int do_proc_dointvec(struct ctl_table *table, int write,
fcfbd547 2334 void __user *buffer, size_t *lenp, loff_t *ppos,
00b7c339 2335 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
fcfbd547
KK
2336 int write, void *data),
2337 void *data)
2338{
8d65af78 2339 return __do_proc_dointvec(table->data, table, write,
fcfbd547
KK
2340 buffer, lenp, ppos, conv, data);
2341}
2342
1da177e4
LT
2343/**
2344 * proc_dointvec - read a vector of integers
2345 * @table: the sysctl table
2346 * @write: %TRUE if this is a write to the sysctl file
1da177e4
LT
2347 * @buffer: the user buffer
2348 * @lenp: the size of the user buffer
2349 * @ppos: file position
2350 *
2351 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2352 * values from/to the user buffer, treated as an ASCII string.
2353 *
2354 * Returns 0 on success.
2355 */
8d65af78 2356int proc_dointvec(struct ctl_table *table, int write,
1da177e4
LT
2357 void __user *buffer, size_t *lenp, loff_t *ppos)
2358{
8d65af78 2359 return do_proc_dointvec(table,write,buffer,lenp,ppos,
1da177e4
LT
2360 NULL,NULL);
2361}
2362
34f5a398 2363/*
25ddbb18
AK
2364 * Taint values can only be increased
2365 * This means we can safely use a temporary.
34f5a398 2366 */
8d65af78 2367static int proc_taint(struct ctl_table *table, int write,
34f5a398
TT
2368 void __user *buffer, size_t *lenp, loff_t *ppos)
2369{
25ddbb18
AK
2370 struct ctl_table t;
2371 unsigned long tmptaint = get_taint();
2372 int err;
34f5a398 2373
91fcd412 2374 if (write && !capable(CAP_SYS_ADMIN))
34f5a398
TT
2375 return -EPERM;
2376
25ddbb18
AK
2377 t = *table;
2378 t.data = &tmptaint;
8d65af78 2379 err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
25ddbb18
AK
2380 if (err < 0)
2381 return err;
2382
2383 if (write) {
2384 /*
2385 * Poor man's atomic or. Not worth adding a primitive
2386 * to everyone's atomic.h for this
2387 */
2388 int i;
2389 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2390 if ((tmptaint >> i) & 1)
2391 add_taint(i);
2392 }
2393 }
2394
2395 return err;
34f5a398
TT
2396}
2397
1da177e4
LT
2398struct do_proc_dointvec_minmax_conv_param {
2399 int *min;
2400 int *max;
2401};
2402
00b7c339
AW
2403static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2404 int *valp,
1da177e4
LT
2405 int write, void *data)
2406{
2407 struct do_proc_dointvec_minmax_conv_param *param = data;
2408 if (write) {
2409 int val = *negp ? -*lvalp : *lvalp;
2410 if ((param->min && *param->min > val) ||
2411 (param->max && *param->max < val))
2412 return -EINVAL;
2413 *valp = val;
2414 } else {
2415 int val = *valp;
2416 if (val < 0) {
00b7c339 2417 *negp = true;
1da177e4
LT
2418 *lvalp = (unsigned long)-val;
2419 } else {
00b7c339 2420 *negp = false;
1da177e4
LT
2421 *lvalp = (unsigned long)val;
2422 }
2423 }
2424 return 0;
2425}
2426
2427/**
2428 * proc_dointvec_minmax - read a vector of integers with min/max values
2429 * @table: the sysctl table
2430 * @write: %TRUE if this is a write to the sysctl file
1da177e4
LT
2431 * @buffer: the user buffer
2432 * @lenp: the size of the user buffer
2433 * @ppos: file position
2434 *
2435 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2436 * values from/to the user buffer, treated as an ASCII string.
2437 *
2438 * This routine will ensure the values are within the range specified by
2439 * table->extra1 (min) and table->extra2 (max).
2440 *
2441 * Returns 0 on success.
2442 */
8d65af78 2443int proc_dointvec_minmax(struct ctl_table *table, int write,
1da177e4
LT
2444 void __user *buffer, size_t *lenp, loff_t *ppos)
2445{
2446 struct do_proc_dointvec_minmax_conv_param param = {
2447 .min = (int *) table->extra1,
2448 .max = (int *) table->extra2,
2449 };
8d65af78 2450 return do_proc_dointvec(table, write, buffer, lenp, ppos,
1da177e4
LT
2451 do_proc_dointvec_minmax_conv, &param);
2452}
2453
d8217f07 2454static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
1da177e4
LT
2455 void __user *buffer,
2456 size_t *lenp, loff_t *ppos,
2457 unsigned long convmul,
2458 unsigned long convdiv)
2459{
00b7c339
AW
2460 unsigned long *i, *min, *max;
2461 int vleft, first = 1, err = 0;
2462 unsigned long page = 0;
2463 size_t left;
2464 char *kbuf;
2465
2466 if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
1da177e4
LT
2467 *lenp = 0;
2468 return 0;
2469 }
00b7c339 2470
fcfbd547 2471 i = (unsigned long *) data;
1da177e4
LT
2472 min = (unsigned long *) table->extra1;
2473 max = (unsigned long *) table->extra2;
2474 vleft = table->maxlen / sizeof(unsigned long);
2475 left = *lenp;
00b7c339
AW
2476
2477 if (write) {
2478 if (left > PAGE_SIZE - 1)
2479 left = PAGE_SIZE - 1;
2480 page = __get_free_page(GFP_TEMPORARY);
2481 kbuf = (char *) page;
2482 if (!kbuf)
2483 return -ENOMEM;
2484 if (copy_from_user(kbuf, buffer, left)) {
2485 err = -EFAULT;
2486 goto free;
2487 }
2488 kbuf[left] = 0;
2489 }
2490
1da177e4 2491 for (; left && vleft--; i++, min++, max++, first=0) {
00b7c339
AW
2492 unsigned long val;
2493
1da177e4 2494 if (write) {
00b7c339
AW
2495 bool neg;
2496
2497 left -= proc_skip_spaces(&kbuf);
2498
2499 err = proc_get_long(&kbuf, &left, &val, &neg,
2500 proc_wspace_sep,
2501 sizeof(proc_wspace_sep), NULL);
2502 if (err)
1da177e4
LT
2503 break;
2504 if (neg)
1da177e4
LT
2505 continue;
2506 if ((min && val < *min) || (max && val > *max))
2507 continue;
2508 *i = val;
2509 } else {
00b7c339 2510 val = convdiv * (*i) / convmul;
1da177e4 2511 if (!first)
00b7c339
AW
2512 err = proc_put_char(&buffer, &left, '\t');
2513 err = proc_put_long(&buffer, &left, val, false);
2514 if (err)
2515 break;
1da177e4
LT
2516 }
2517 }
2518
00b7c339
AW
2519 if (!write && !first && left && !err)
2520 err = proc_put_char(&buffer, &left, '\n');
2521 if (write && !err)
2522 left -= proc_skip_spaces(&kbuf);
2523free:
1da177e4 2524 if (write) {
00b7c339
AW
2525 free_page(page);
2526 if (first)
2527 return err ? : -EINVAL;
1da177e4 2528 }
1da177e4
LT
2529 *lenp -= left;
2530 *ppos += *lenp;
00b7c339 2531 return err;
1da177e4
LT
2532}
2533
d8217f07 2534static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
fcfbd547
KK
2535 void __user *buffer,
2536 size_t *lenp, loff_t *ppos,
2537 unsigned long convmul,
2538 unsigned long convdiv)
2539{
2540 return __do_proc_doulongvec_minmax(table->data, table, write,
8d65af78 2541 buffer, lenp, ppos, convmul, convdiv);
fcfbd547
KK
2542}
2543
1da177e4
LT
2544/**
2545 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2546 * @table: the sysctl table
2547 * @write: %TRUE if this is a write to the sysctl file
1da177e4
LT
2548 * @buffer: the user buffer
2549 * @lenp: the size of the user buffer
2550 * @ppos: file position
2551 *
2552 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2553 * values from/to the user buffer, treated as an ASCII string.
2554 *
2555 * This routine will ensure the values are within the range specified by
2556 * table->extra1 (min) and table->extra2 (max).
2557 *
2558 * Returns 0 on success.
2559 */
8d65af78 2560int proc_doulongvec_minmax(struct ctl_table *table, int write,
1da177e4
LT
2561 void __user *buffer, size_t *lenp, loff_t *ppos)
2562{
8d65af78 2563 return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
1da177e4
LT
2564}
2565
2566/**
2567 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2568 * @table: the sysctl table
2569 * @write: %TRUE if this is a write to the sysctl file
1da177e4
LT
2570 * @buffer: the user buffer
2571 * @lenp: the size of the user buffer
2572 * @ppos: file position
2573 *
2574 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2575 * values from/to the user buffer, treated as an ASCII string. The values
2576 * are treated as milliseconds, and converted to jiffies when they are stored.
2577 *
2578 * This routine will ensure the values are within the range specified by
2579 * table->extra1 (min) and table->extra2 (max).
2580 *
2581 * Returns 0 on success.
2582 */
d8217f07 2583int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
1da177e4
LT
2584 void __user *buffer,
2585 size_t *lenp, loff_t *ppos)
2586{
8d65af78 2587 return do_proc_doulongvec_minmax(table, write, buffer,
1da177e4
LT
2588 lenp, ppos, HZ, 1000l);
2589}
2590
2591
00b7c339 2592static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
1da177e4
LT
2593 int *valp,
2594 int write, void *data)
2595{
2596 if (write) {
cba9f33d
BS
2597 if (*lvalp > LONG_MAX / HZ)
2598 return 1;
1da177e4
LT
2599 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2600 } else {
2601 int val = *valp;
2602 unsigned long lval;
2603 if (val < 0) {
00b7c339 2604 *negp = true;
1da177e4
LT
2605 lval = (unsigned long)-val;
2606 } else {
00b7c339 2607 *negp = false;
1da177e4
LT
2608 lval = (unsigned long)val;
2609 }
2610 *lvalp = lval / HZ;
2611 }
2612 return 0;
2613}
2614
00b7c339 2615static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
1da177e4
LT
2616 int *valp,
2617 int write, void *data)
2618{
2619 if (write) {
cba9f33d
BS
2620 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2621 return 1;
1da177e4
LT
2622 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2623 } else {
2624 int val = *valp;
2625 unsigned long lval;
2626 if (val < 0) {
00b7c339 2627 *negp = true;
1da177e4
LT
2628 lval = (unsigned long)-val;
2629 } else {
00b7c339 2630 *negp = false;
1da177e4
LT
2631 lval = (unsigned long)val;
2632 }
2633 *lvalp = jiffies_to_clock_t(lval);
2634 }
2635 return 0;
2636}
2637
00b7c339 2638static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
1da177e4
LT
2639 int *valp,
2640 int write, void *data)
2641{
2642 if (write) {
2643 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2644 } else {
2645 int val = *valp;
2646 unsigned long lval;
2647 if (val < 0) {
00b7c339 2648 *negp = true;
1da177e4
LT
2649 lval = (unsigned long)-val;
2650 } else {
00b7c339 2651 *negp = false;
1da177e4
LT
2652 lval = (unsigned long)val;
2653 }
2654 *lvalp = jiffies_to_msecs(lval);
2655 }
2656 return 0;
2657}
2658
2659/**
2660 * proc_dointvec_jiffies - read a vector of integers as seconds
2661 * @table: the sysctl table
2662 * @write: %TRUE if this is a write to the sysctl file
1da177e4
LT
2663 * @buffer: the user buffer
2664 * @lenp: the size of the user buffer
2665 * @ppos: file position
2666 *
2667 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2668 * values from/to the user buffer, treated as an ASCII string.
2669 * The values read are assumed to be in seconds, and are converted into
2670 * jiffies.
2671 *
2672 * Returns 0 on success.
2673 */
8d65af78 2674int proc_dointvec_jiffies(struct ctl_table *table, int write,
1da177e4
LT
2675 void __user *buffer, size_t *lenp, loff_t *ppos)
2676{
8d65af78 2677 return do_proc_dointvec(table,write,buffer,lenp,ppos,
1da177e4
LT
2678 do_proc_dointvec_jiffies_conv,NULL);
2679}
2680
2681/**
2682 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2683 * @table: the sysctl table
2684 * @write: %TRUE if this is a write to the sysctl file
1da177e4
LT
2685 * @buffer: the user buffer
2686 * @lenp: the size of the user buffer
1e5d5331 2687 * @ppos: pointer to the file position
1da177e4
LT
2688 *
2689 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2690 * values from/to the user buffer, treated as an ASCII string.
2691 * The values read are assumed to be in 1/USER_HZ seconds, and
2692 * are converted into jiffies.
2693 *
2694 * Returns 0 on success.
2695 */
8d65af78 2696int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
1da177e4
LT
2697 void __user *buffer, size_t *lenp, loff_t *ppos)
2698{
8d65af78 2699 return do_proc_dointvec(table,write,buffer,lenp,ppos,
1da177e4
LT
2700 do_proc_dointvec_userhz_jiffies_conv,NULL);
2701}
2702
2703/**
2704 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2705 * @table: the sysctl table
2706 * @write: %TRUE if this is a write to the sysctl file
1da177e4
LT
2707 * @buffer: the user buffer
2708 * @lenp: the size of the user buffer
67be2dd1
MW
2709 * @ppos: file position
2710 * @ppos: the current position in the file
1da177e4
LT
2711 *
2712 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2713 * values from/to the user buffer, treated as an ASCII string.
2714 * The values read are assumed to be in 1/1000 seconds, and
2715 * are converted into jiffies.
2716 *
2717 * Returns 0 on success.
2718 */
8d65af78 2719int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
1da177e4
LT
2720 void __user *buffer, size_t *lenp, loff_t *ppos)
2721{
8d65af78 2722 return do_proc_dointvec(table, write, buffer, lenp, ppos,
1da177e4
LT
2723 do_proc_dointvec_ms_jiffies_conv, NULL);
2724}
2725
8d65af78 2726static int proc_do_cad_pid(struct ctl_table *table, int write,
9ec52099
CLG
2727 void __user *buffer, size_t *lenp, loff_t *ppos)
2728{
2729 struct pid *new_pid;
2730 pid_t tmp;
2731 int r;
2732
6c5f3e7b 2733 tmp = pid_vnr(cad_pid);
9ec52099 2734
8d65af78 2735 r = __do_proc_dointvec(&tmp, table, write, buffer,
9ec52099
CLG
2736 lenp, ppos, NULL, NULL);
2737 if (r || !write)
2738 return r;
2739
2740 new_pid = find_get_pid(tmp);
2741 if (!new_pid)
2742 return -ESRCH;
2743
2744 put_pid(xchg(&cad_pid, new_pid));
2745 return 0;
2746}
2747
9f977fb7
OP
2748/**
2749 * proc_do_large_bitmap - read/write from/to a large bitmap
2750 * @table: the sysctl table
2751 * @write: %TRUE if this is a write to the sysctl file
2752 * @buffer: the user buffer
2753 * @lenp: the size of the user buffer
2754 * @ppos: file position
2755 *
2756 * The bitmap is stored at table->data and the bitmap length (in bits)
2757 * in table->maxlen.
2758 *
2759 * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2760 * large bitmaps may be represented in a compact manner. Writing into
2761 * the file will clear the bitmap then update it with the given input.
2762 *
2763 * Returns 0 on success.
2764 */
2765int proc_do_large_bitmap(struct ctl_table *table, int write,
2766 void __user *buffer, size_t *lenp, loff_t *ppos)
2767{
2768 int err = 0;
2769 bool first = 1;
2770 size_t left = *lenp;
2771 unsigned long bitmap_len = table->maxlen;
2772 unsigned long *bitmap = (unsigned long *) table->data;
2773 unsigned long *tmp_bitmap = NULL;
2774 char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
2775
2776 if (!bitmap_len || !left || (*ppos && !write)) {
2777 *lenp = 0;
2778 return 0;
2779 }
2780
2781 if (write) {
2782 unsigned long page = 0;
2783 char *kbuf;
2784
2785 if (left > PAGE_SIZE - 1)
2786 left = PAGE_SIZE - 1;
2787
2788 page = __get_free_page(GFP_TEMPORARY);
2789 kbuf = (char *) page;
2790 if (!kbuf)
2791 return -ENOMEM;
2792 if (copy_from_user(kbuf, buffer, left)) {
2793 free_page(page);
2794 return -EFAULT;
2795 }
2796 kbuf[left] = 0;
2797
2798 tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
2799 GFP_KERNEL);
2800 if (!tmp_bitmap) {
2801 free_page(page);
2802 return -ENOMEM;
2803 }
2804 proc_skip_char(&kbuf, &left, '\n');
2805 while (!err && left) {
2806 unsigned long val_a, val_b;
2807 bool neg;
2808
2809 err = proc_get_long(&kbuf, &left, &val_a, &neg, tr_a,
2810 sizeof(tr_a), &c);
2811 if (err)
2812 break;
2813 if (val_a >= bitmap_len || neg) {
2814 err = -EINVAL;
2815 break;
2816 }
2817
2818 val_b = val_a;
2819 if (left) {
2820 kbuf++;
2821 left--;
2822 }
2823
2824 if (c == '-') {
2825 err = proc_get_long(&kbuf, &left, &val_b,
2826 &neg, tr_b, sizeof(tr_b),
2827 &c);
2828 if (err)
2829 break;
2830 if (val_b >= bitmap_len || neg ||
2831 val_a > val_b) {
2832 err = -EINVAL;
2833 break;
2834 }
2835 if (left) {
2836 kbuf++;
2837 left--;
2838 }
2839 }
2840
2841 while (val_a <= val_b)
2842 set_bit(val_a++, tmp_bitmap);
2843
2844 first = 0;
2845 proc_skip_char(&kbuf, &left, '\n');
2846 }
2847 free_page(page);
2848 } else {
2849 unsigned long bit_a, bit_b = 0;
2850
2851 while (left) {
2852 bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
2853 if (bit_a >= bitmap_len)
2854 break;
2855 bit_b = find_next_zero_bit(bitmap, bitmap_len,
2856 bit_a + 1) - 1;
2857
2858 if (!first) {
2859 err = proc_put_char(&buffer, &left, ',');
2860 if (err)
2861 break;
2862 }
2863 err = proc_put_long(&buffer, &left, bit_a, false);
2864 if (err)
2865 break;
2866 if (bit_a != bit_b) {
2867 err = proc_put_char(&buffer, &left, '-');
2868 if (err)
2869 break;
2870 err = proc_put_long(&buffer, &left, bit_b, false);
2871 if (err)
2872 break;
2873 }
2874
2875 first = 0; bit_b++;
2876 }
2877 if (!err)
2878 err = proc_put_char(&buffer, &left, '\n');
2879 }
2880
2881 if (!err) {
2882 if (write) {
2883 if (*ppos)
2884 bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
2885 else
2886 memcpy(bitmap, tmp_bitmap,
2887 BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long));
2888 }
2889 kfree(tmp_bitmap);
2890 *lenp -= left;
2891 *ppos += *lenp;
2892 return 0;
2893 } else {
2894 kfree(tmp_bitmap);
2895 return err;
2896 }
2897}
2898
1da177e4
LT
2899#else /* CONFIG_PROC_FS */
2900
8d65af78 2901int proc_dostring(struct ctl_table *table, int write,
1da177e4
LT
2902 void __user *buffer, size_t *lenp, loff_t *ppos)
2903{
2904 return -ENOSYS;
2905}
2906
8d65af78 2907int proc_dointvec(struct ctl_table *table, int write,
1da177e4 2908 void __user *buffer, size_t *lenp, loff_t *ppos)
1da177e4
LT
2909{
2910 return -ENOSYS;
2911}
2912
8d65af78 2913int proc_dointvec_minmax(struct ctl_table *table, int write,
1da177e4
LT
2914 void __user *buffer, size_t *lenp, loff_t *ppos)
2915{
2916 return -ENOSYS;
2917}
2918
8d65af78 2919int proc_dointvec_jiffies(struct ctl_table *table, int write,
1da177e4
LT
2920 void __user *buffer, size_t *lenp, loff_t *ppos)
2921{
2922 return -ENOSYS;
2923}
2924
8d65af78 2925int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
1da177e4
LT
2926 void __user *buffer, size_t *lenp, loff_t *ppos)
2927{
2928 return -ENOSYS;
2929}
2930
8d65af78 2931int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
1da177e4
LT
2932 void __user *buffer, size_t *lenp, loff_t *ppos)
2933{
2934 return -ENOSYS;
2935}
2936
8d65af78 2937int proc_doulongvec_minmax(struct ctl_table *table, int write,
1da177e4
LT
2938 void __user *buffer, size_t *lenp, loff_t *ppos)
2939{
2940 return -ENOSYS;
2941}
2942
d8217f07 2943int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
1da177e4
LT
2944 void __user *buffer,
2945 size_t *lenp, loff_t *ppos)
2946{
2947 return -ENOSYS;
2948}
2949
2950
2951#endif /* CONFIG_PROC_FS */
2952
1da177e4
LT
2953/*
2954 * No sense putting this after each symbol definition, twice,
2955 * exception granted :-)
2956 */
2957EXPORT_SYMBOL(proc_dointvec);
2958EXPORT_SYMBOL(proc_dointvec_jiffies);
2959EXPORT_SYMBOL(proc_dointvec_minmax);
2960EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2961EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2962EXPORT_SYMBOL(proc_dostring);
2963EXPORT_SYMBOL(proc_doulongvec_minmax);
2964EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2965EXPORT_SYMBOL(register_sysctl_table);
29e796fd 2966EXPORT_SYMBOL(register_sysctl_paths);
1da177e4 2967EXPORT_SYMBOL(unregister_sysctl_table);