ACPI: thinkpad-acpi: preserve radio state across shutdown
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / kernel / sysctl.c
blob6816e6db0ab0709c9029c77357bea2d0d6e4d429
1 /*
2 * sysctl.c: General linux system control interface
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
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>
26 #include <linux/proc_fs.h>
27 #include <linux/security.h>
28 #include <linux/ctype.h>
29 #include <linux/utsname.h>
30 #include <linux/smp_lock.h>
31 #include <linux/fs.h>
32 #include <linux/init.h>
33 #include <linux/kernel.h>
34 #include <linux/kobject.h>
35 #include <linux/net.h>
36 #include <linux/sysrq.h>
37 #include <linux/highuid.h>
38 #include <linux/writeback.h>
39 #include <linux/hugetlb.h>
40 #include <linux/initrd.h>
41 #include <linux/key.h>
42 #include <linux/times.h>
43 #include <linux/limits.h>
44 #include <linux/dcache.h>
45 #include <linux/syscalls.h>
46 #include <linux/vmstat.h>
47 #include <linux/nfs_fs.h>
48 #include <linux/acpi.h>
49 #include <linux/reboot.h>
50 #include <linux/ftrace.h>
52 #include <asm/uaccess.h>
53 #include <asm/processor.h>
55 #ifdef CONFIG_X86
56 #include <asm/nmi.h>
57 #include <asm/stacktrace.h>
58 #include <asm/io.h>
59 #endif
61 static int deprecated_sysctl_warning(struct __sysctl_args *args);
63 #if defined(CONFIG_SYSCTL)
65 /* External variables not in a header file. */
66 extern int C_A_D;
67 extern int print_fatal_signals;
68 extern int sysctl_overcommit_memory;
69 extern int sysctl_overcommit_ratio;
70 extern int sysctl_panic_on_oom;
71 extern int sysctl_oom_kill_allocating_task;
72 extern int sysctl_oom_dump_tasks;
73 extern int max_threads;
74 extern int core_uses_pid;
75 extern int suid_dumpable;
76 extern char core_pattern[];
77 extern int pid_max;
78 extern int min_free_kbytes;
79 extern int pid_max_min, pid_max_max;
80 extern int sysctl_drop_caches;
81 extern int percpu_pagelist_fraction;
82 extern int compat_log;
83 extern int maps_protect;
84 extern int latencytop_enabled;
85 extern int sysctl_nr_open_min, sysctl_nr_open_max;
86 #ifdef CONFIG_RCU_TORTURE_TEST
87 extern int rcutorture_runnable;
88 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
90 /* Constants used for minimum and maximum */
91 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_DETECT_SOFTLOCKUP)
92 static int one = 1;
93 #endif
95 #ifdef CONFIG_DETECT_SOFTLOCKUP
96 static int sixty = 60;
97 static int neg_one = -1;
98 #endif
100 #ifdef CONFIG_MMU
101 static int two = 2;
102 #endif
104 static int zero;
105 static int one_hundred = 100;
107 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
108 static int maxolduid = 65535;
109 static int minolduid;
110 static int min_percpu_pagelist_fract = 8;
112 static int ngroups_max = NGROUPS_MAX;
114 #ifdef CONFIG_MODULES
115 extern char modprobe_path[];
116 #endif
117 #ifdef CONFIG_CHR_DEV_SG
118 extern int sg_big_buff;
119 #endif
121 #ifdef __sparc__
122 extern char reboot_command [];
123 extern int stop_a_enabled;
124 extern int scons_pwroff;
125 #endif
127 #ifdef __hppa__
128 extern int pwrsw_enabled;
129 extern int unaligned_enabled;
130 #endif
132 #ifdef CONFIG_S390
133 #ifdef CONFIG_MATHEMU
134 extern int sysctl_ieee_emulation_warnings;
135 #endif
136 extern int sysctl_userprocess_debug;
137 extern int spin_retry;
138 #endif
140 #ifdef CONFIG_BSD_PROCESS_ACCT
141 extern int acct_parm[];
142 #endif
144 #ifdef CONFIG_IA64
145 extern int no_unaligned_warning;
146 #endif
148 #ifdef CONFIG_RT_MUTEXES
149 extern int max_lock_depth;
150 #endif
152 #ifdef CONFIG_PROC_SYSCTL
153 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
154 void __user *buffer, size_t *lenp, loff_t *ppos);
155 static int proc_dointvec_taint(struct ctl_table *table, int write, struct file *filp,
156 void __user *buffer, size_t *lenp, loff_t *ppos);
157 #endif
159 static struct ctl_table root_table[];
160 static struct ctl_table_root sysctl_table_root;
161 static struct ctl_table_header root_table_header = {
162 .count = 1,
163 .ctl_table = root_table,
164 .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
165 .root = &sysctl_table_root,
166 .set = &sysctl_table_root.default_set,
168 static struct ctl_table_root sysctl_table_root = {
169 .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
170 .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
173 static struct ctl_table kern_table[];
174 static struct ctl_table vm_table[];
175 static struct ctl_table fs_table[];
176 static struct ctl_table debug_table[];
177 static struct ctl_table dev_table[];
178 extern struct ctl_table random_table[];
179 #ifdef CONFIG_INOTIFY_USER
180 extern struct ctl_table inotify_table[];
181 #endif
182 #ifdef CONFIG_EPOLL
183 extern struct ctl_table epoll_table[];
184 #endif
186 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
187 int sysctl_legacy_va_layout;
188 #endif
190 extern int prove_locking;
191 extern int lock_stat;
193 /* The default sysctl tables: */
195 static struct ctl_table root_table[] = {
197 .ctl_name = CTL_KERN,
198 .procname = "kernel",
199 .mode = 0555,
200 .child = kern_table,
203 .ctl_name = CTL_VM,
204 .procname = "vm",
205 .mode = 0555,
206 .child = vm_table,
209 .ctl_name = CTL_FS,
210 .procname = "fs",
211 .mode = 0555,
212 .child = fs_table,
215 .ctl_name = CTL_DEBUG,
216 .procname = "debug",
217 .mode = 0555,
218 .child = debug_table,
221 .ctl_name = CTL_DEV,
222 .procname = "dev",
223 .mode = 0555,
224 .child = dev_table,
227 * NOTE: do not add new entries to this table unless you have read
228 * Documentation/sysctl/ctl_unnumbered.txt
230 { .ctl_name = 0 }
233 #ifdef CONFIG_SCHED_DEBUG
234 static int min_sched_granularity_ns = 100000; /* 100 usecs */
235 static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
236 static int min_wakeup_granularity_ns; /* 0 usecs */
237 static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
238 #endif
240 static struct ctl_table kern_table[] = {
241 #ifdef CONFIG_SCHED_DEBUG
243 .ctl_name = CTL_UNNUMBERED,
244 .procname = "sched_min_granularity_ns",
245 .data = &sysctl_sched_min_granularity,
246 .maxlen = sizeof(unsigned int),
247 .mode = 0644,
248 .proc_handler = &sched_nr_latency_handler,
249 .strategy = &sysctl_intvec,
250 .extra1 = &min_sched_granularity_ns,
251 .extra2 = &max_sched_granularity_ns,
254 .ctl_name = CTL_UNNUMBERED,
255 .procname = "sched_latency_ns",
256 .data = &sysctl_sched_latency,
257 .maxlen = sizeof(unsigned int),
258 .mode = 0644,
259 .proc_handler = &sched_nr_latency_handler,
260 .strategy = &sysctl_intvec,
261 .extra1 = &min_sched_granularity_ns,
262 .extra2 = &max_sched_granularity_ns,
265 .ctl_name = CTL_UNNUMBERED,
266 .procname = "sched_wakeup_granularity_ns",
267 .data = &sysctl_sched_wakeup_granularity,
268 .maxlen = sizeof(unsigned int),
269 .mode = 0644,
270 .proc_handler = &proc_dointvec_minmax,
271 .strategy = &sysctl_intvec,
272 .extra1 = &min_wakeup_granularity_ns,
273 .extra2 = &max_wakeup_granularity_ns,
276 .ctl_name = CTL_UNNUMBERED,
277 .procname = "sched_shares_ratelimit",
278 .data = &sysctl_sched_shares_ratelimit,
279 .maxlen = sizeof(unsigned int),
280 .mode = 0644,
281 .proc_handler = &proc_dointvec,
284 .ctl_name = CTL_UNNUMBERED,
285 .procname = "sched_child_runs_first",
286 .data = &sysctl_sched_child_runs_first,
287 .maxlen = sizeof(unsigned int),
288 .mode = 0644,
289 .proc_handler = &proc_dointvec,
292 .ctl_name = CTL_UNNUMBERED,
293 .procname = "sched_features",
294 .data = &sysctl_sched_features,
295 .maxlen = sizeof(unsigned int),
296 .mode = 0644,
297 .proc_handler = &proc_dointvec,
300 .ctl_name = CTL_UNNUMBERED,
301 .procname = "sched_migration_cost",
302 .data = &sysctl_sched_migration_cost,
303 .maxlen = sizeof(unsigned int),
304 .mode = 0644,
305 .proc_handler = &proc_dointvec,
308 .ctl_name = CTL_UNNUMBERED,
309 .procname = "sched_nr_migrate",
310 .data = &sysctl_sched_nr_migrate,
311 .maxlen = sizeof(unsigned int),
312 .mode = 0644,
313 .proc_handler = &proc_dointvec,
315 #endif
317 .ctl_name = CTL_UNNUMBERED,
318 .procname = "sched_rt_period_us",
319 .data = &sysctl_sched_rt_period,
320 .maxlen = sizeof(unsigned int),
321 .mode = 0644,
322 .proc_handler = &sched_rt_handler,
325 .ctl_name = CTL_UNNUMBERED,
326 .procname = "sched_rt_runtime_us",
327 .data = &sysctl_sched_rt_runtime,
328 .maxlen = sizeof(int),
329 .mode = 0644,
330 .proc_handler = &sched_rt_handler,
333 .ctl_name = CTL_UNNUMBERED,
334 .procname = "sched_compat_yield",
335 .data = &sysctl_sched_compat_yield,
336 .maxlen = sizeof(unsigned int),
337 .mode = 0644,
338 .proc_handler = &proc_dointvec,
340 #ifdef CONFIG_PROVE_LOCKING
342 .ctl_name = CTL_UNNUMBERED,
343 .procname = "prove_locking",
344 .data = &prove_locking,
345 .maxlen = sizeof(int),
346 .mode = 0644,
347 .proc_handler = &proc_dointvec,
349 #endif
350 #ifdef CONFIG_LOCK_STAT
352 .ctl_name = CTL_UNNUMBERED,
353 .procname = "lock_stat",
354 .data = &lock_stat,
355 .maxlen = sizeof(int),
356 .mode = 0644,
357 .proc_handler = &proc_dointvec,
359 #endif
361 .ctl_name = KERN_PANIC,
362 .procname = "panic",
363 .data = &panic_timeout,
364 .maxlen = sizeof(int),
365 .mode = 0644,
366 .proc_handler = &proc_dointvec,
369 .ctl_name = KERN_CORE_USES_PID,
370 .procname = "core_uses_pid",
371 .data = &core_uses_pid,
372 .maxlen = sizeof(int),
373 .mode = 0644,
374 .proc_handler = &proc_dointvec,
377 .ctl_name = KERN_CORE_PATTERN,
378 .procname = "core_pattern",
379 .data = core_pattern,
380 .maxlen = CORENAME_MAX_SIZE,
381 .mode = 0644,
382 .proc_handler = &proc_dostring,
383 .strategy = &sysctl_string,
385 #ifdef CONFIG_PROC_SYSCTL
387 .procname = "tainted",
388 .data = &tainted,
389 .maxlen = sizeof(int),
390 .mode = 0644,
391 .proc_handler = &proc_dointvec_taint,
393 #endif
394 #ifdef CONFIG_LATENCYTOP
396 .procname = "latencytop",
397 .data = &latencytop_enabled,
398 .maxlen = sizeof(int),
399 .mode = 0644,
400 .proc_handler = &proc_dointvec,
402 #endif
403 #ifdef CONFIG_BLK_DEV_INITRD
405 .ctl_name = KERN_REALROOTDEV,
406 .procname = "real-root-dev",
407 .data = &real_root_dev,
408 .maxlen = sizeof(int),
409 .mode = 0644,
410 .proc_handler = &proc_dointvec,
412 #endif
414 .ctl_name = CTL_UNNUMBERED,
415 .procname = "print-fatal-signals",
416 .data = &print_fatal_signals,
417 .maxlen = sizeof(int),
418 .mode = 0644,
419 .proc_handler = &proc_dointvec,
421 #ifdef __sparc__
423 .ctl_name = KERN_SPARC_REBOOT,
424 .procname = "reboot-cmd",
425 .data = reboot_command,
426 .maxlen = 256,
427 .mode = 0644,
428 .proc_handler = &proc_dostring,
429 .strategy = &sysctl_string,
432 .ctl_name = KERN_SPARC_STOP_A,
433 .procname = "stop-a",
434 .data = &stop_a_enabled,
435 .maxlen = sizeof (int),
436 .mode = 0644,
437 .proc_handler = &proc_dointvec,
440 .ctl_name = KERN_SPARC_SCONS_PWROFF,
441 .procname = "scons-poweroff",
442 .data = &scons_pwroff,
443 .maxlen = sizeof (int),
444 .mode = 0644,
445 .proc_handler = &proc_dointvec,
447 #endif
448 #ifdef __hppa__
450 .ctl_name = KERN_HPPA_PWRSW,
451 .procname = "soft-power",
452 .data = &pwrsw_enabled,
453 .maxlen = sizeof (int),
454 .mode = 0644,
455 .proc_handler = &proc_dointvec,
458 .ctl_name = KERN_HPPA_UNALIGNED,
459 .procname = "unaligned-trap",
460 .data = &unaligned_enabled,
461 .maxlen = sizeof (int),
462 .mode = 0644,
463 .proc_handler = &proc_dointvec,
465 #endif
467 .ctl_name = KERN_CTLALTDEL,
468 .procname = "ctrl-alt-del",
469 .data = &C_A_D,
470 .maxlen = sizeof(int),
471 .mode = 0644,
472 .proc_handler = &proc_dointvec,
474 #ifdef CONFIG_FTRACE
476 .ctl_name = CTL_UNNUMBERED,
477 .procname = "ftrace_enabled",
478 .data = &ftrace_enabled,
479 .maxlen = sizeof(int),
480 .mode = 0644,
481 .proc_handler = &ftrace_enable_sysctl,
483 #endif
484 #ifdef CONFIG_MODULES
486 .ctl_name = KERN_MODPROBE,
487 .procname = "modprobe",
488 .data = &modprobe_path,
489 .maxlen = KMOD_PATH_LEN,
490 .mode = 0644,
491 .proc_handler = &proc_dostring,
492 .strategy = &sysctl_string,
494 #endif
495 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
497 .ctl_name = KERN_HOTPLUG,
498 .procname = "hotplug",
499 .data = &uevent_helper,
500 .maxlen = UEVENT_HELPER_PATH_LEN,
501 .mode = 0644,
502 .proc_handler = &proc_dostring,
503 .strategy = &sysctl_string,
505 #endif
506 #ifdef CONFIG_CHR_DEV_SG
508 .ctl_name = KERN_SG_BIG_BUFF,
509 .procname = "sg-big-buff",
510 .data = &sg_big_buff,
511 .maxlen = sizeof (int),
512 .mode = 0444,
513 .proc_handler = &proc_dointvec,
515 #endif
516 #ifdef CONFIG_BSD_PROCESS_ACCT
518 .ctl_name = KERN_ACCT,
519 .procname = "acct",
520 .data = &acct_parm,
521 .maxlen = 3*sizeof(int),
522 .mode = 0644,
523 .proc_handler = &proc_dointvec,
525 #endif
526 #ifdef CONFIG_MAGIC_SYSRQ
528 .ctl_name = KERN_SYSRQ,
529 .procname = "sysrq",
530 .data = &__sysrq_enabled,
531 .maxlen = sizeof (int),
532 .mode = 0644,
533 .proc_handler = &proc_dointvec,
535 #endif
536 #ifdef CONFIG_PROC_SYSCTL
538 .procname = "cad_pid",
539 .data = NULL,
540 .maxlen = sizeof (int),
541 .mode = 0600,
542 .proc_handler = &proc_do_cad_pid,
544 #endif
546 .ctl_name = KERN_MAX_THREADS,
547 .procname = "threads-max",
548 .data = &max_threads,
549 .maxlen = sizeof(int),
550 .mode = 0644,
551 .proc_handler = &proc_dointvec,
554 .ctl_name = KERN_RANDOM,
555 .procname = "random",
556 .mode = 0555,
557 .child = random_table,
560 .ctl_name = KERN_OVERFLOWUID,
561 .procname = "overflowuid",
562 .data = &overflowuid,
563 .maxlen = sizeof(int),
564 .mode = 0644,
565 .proc_handler = &proc_dointvec_minmax,
566 .strategy = &sysctl_intvec,
567 .extra1 = &minolduid,
568 .extra2 = &maxolduid,
571 .ctl_name = KERN_OVERFLOWGID,
572 .procname = "overflowgid",
573 .data = &overflowgid,
574 .maxlen = sizeof(int),
575 .mode = 0644,
576 .proc_handler = &proc_dointvec_minmax,
577 .strategy = &sysctl_intvec,
578 .extra1 = &minolduid,
579 .extra2 = &maxolduid,
581 #ifdef CONFIG_S390
582 #ifdef CONFIG_MATHEMU
584 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
585 .procname = "ieee_emulation_warnings",
586 .data = &sysctl_ieee_emulation_warnings,
587 .maxlen = sizeof(int),
588 .mode = 0644,
589 .proc_handler = &proc_dointvec,
591 #endif
593 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
594 .procname = "userprocess_debug",
595 .data = &sysctl_userprocess_debug,
596 .maxlen = sizeof(int),
597 .mode = 0644,
598 .proc_handler = &proc_dointvec,
600 #endif
602 .ctl_name = KERN_PIDMAX,
603 .procname = "pid_max",
604 .data = &pid_max,
605 .maxlen = sizeof (int),
606 .mode = 0644,
607 .proc_handler = &proc_dointvec_minmax,
608 .strategy = sysctl_intvec,
609 .extra1 = &pid_max_min,
610 .extra2 = &pid_max_max,
613 .ctl_name = KERN_PANIC_ON_OOPS,
614 .procname = "panic_on_oops",
615 .data = &panic_on_oops,
616 .maxlen = sizeof(int),
617 .mode = 0644,
618 .proc_handler = &proc_dointvec,
620 #if defined CONFIG_PRINTK
622 .ctl_name = KERN_PRINTK,
623 .procname = "printk",
624 .data = &console_loglevel,
625 .maxlen = 4*sizeof(int),
626 .mode = 0644,
627 .proc_handler = &proc_dointvec,
630 .ctl_name = KERN_PRINTK_RATELIMIT,
631 .procname = "printk_ratelimit",
632 .data = &printk_ratelimit_state.interval,
633 .maxlen = sizeof(int),
634 .mode = 0644,
635 .proc_handler = &proc_dointvec_jiffies,
636 .strategy = &sysctl_jiffies,
639 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
640 .procname = "printk_ratelimit_burst",
641 .data = &printk_ratelimit_state.burst,
642 .maxlen = sizeof(int),
643 .mode = 0644,
644 .proc_handler = &proc_dointvec,
646 #endif
648 .ctl_name = KERN_NGROUPS_MAX,
649 .procname = "ngroups_max",
650 .data = &ngroups_max,
651 .maxlen = sizeof (int),
652 .mode = 0444,
653 .proc_handler = &proc_dointvec,
655 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
657 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
658 .procname = "unknown_nmi_panic",
659 .data = &unknown_nmi_panic,
660 .maxlen = sizeof (int),
661 .mode = 0644,
662 .proc_handler = &proc_dointvec,
665 .procname = "nmi_watchdog",
666 .data = &nmi_watchdog_enabled,
667 .maxlen = sizeof (int),
668 .mode = 0644,
669 .proc_handler = &proc_nmi_enabled,
671 #endif
672 #if defined(CONFIG_X86)
674 .ctl_name = KERN_PANIC_ON_NMI,
675 .procname = "panic_on_unrecovered_nmi",
676 .data = &panic_on_unrecovered_nmi,
677 .maxlen = sizeof(int),
678 .mode = 0644,
679 .proc_handler = &proc_dointvec,
682 .ctl_name = KERN_BOOTLOADER_TYPE,
683 .procname = "bootloader_type",
684 .data = &bootloader_type,
685 .maxlen = sizeof (int),
686 .mode = 0444,
687 .proc_handler = &proc_dointvec,
690 .ctl_name = CTL_UNNUMBERED,
691 .procname = "kstack_depth_to_print",
692 .data = &kstack_depth_to_print,
693 .maxlen = sizeof(int),
694 .mode = 0644,
695 .proc_handler = &proc_dointvec,
698 .ctl_name = CTL_UNNUMBERED,
699 .procname = "io_delay_type",
700 .data = &io_delay_type,
701 .maxlen = sizeof(int),
702 .mode = 0644,
703 .proc_handler = &proc_dointvec,
705 #endif
706 #if defined(CONFIG_MMU)
708 .ctl_name = KERN_RANDOMIZE,
709 .procname = "randomize_va_space",
710 .data = &randomize_va_space,
711 .maxlen = sizeof(int),
712 .mode = 0644,
713 .proc_handler = &proc_dointvec,
715 #endif
716 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
718 .ctl_name = KERN_SPIN_RETRY,
719 .procname = "spin_retry",
720 .data = &spin_retry,
721 .maxlen = sizeof (int),
722 .mode = 0644,
723 .proc_handler = &proc_dointvec,
725 #endif
726 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
728 .procname = "acpi_video_flags",
729 .data = &acpi_realmode_flags,
730 .maxlen = sizeof (unsigned long),
731 .mode = 0644,
732 .proc_handler = &proc_doulongvec_minmax,
734 #endif
735 #ifdef CONFIG_IA64
737 .ctl_name = KERN_IA64_UNALIGNED,
738 .procname = "ignore-unaligned-usertrap",
739 .data = &no_unaligned_warning,
740 .maxlen = sizeof (int),
741 .mode = 0644,
742 .proc_handler = &proc_dointvec,
744 #endif
745 #ifdef CONFIG_DETECT_SOFTLOCKUP
747 .ctl_name = CTL_UNNUMBERED,
748 .procname = "softlockup_panic",
749 .data = &softlockup_panic,
750 .maxlen = sizeof(int),
751 .mode = 0644,
752 .proc_handler = &proc_dointvec_minmax,
753 .strategy = &sysctl_intvec,
754 .extra1 = &zero,
755 .extra2 = &one,
758 .ctl_name = CTL_UNNUMBERED,
759 .procname = "softlockup_thresh",
760 .data = &softlockup_thresh,
761 .maxlen = sizeof(int),
762 .mode = 0644,
763 .proc_handler = &proc_dointvec_minmax,
764 .strategy = &sysctl_intvec,
765 .extra1 = &neg_one,
766 .extra2 = &sixty,
769 .ctl_name = CTL_UNNUMBERED,
770 .procname = "hung_task_check_count",
771 .data = &sysctl_hung_task_check_count,
772 .maxlen = sizeof(unsigned long),
773 .mode = 0644,
774 .proc_handler = &proc_doulongvec_minmax,
775 .strategy = &sysctl_intvec,
778 .ctl_name = CTL_UNNUMBERED,
779 .procname = "hung_task_timeout_secs",
780 .data = &sysctl_hung_task_timeout_secs,
781 .maxlen = sizeof(unsigned long),
782 .mode = 0644,
783 .proc_handler = &proc_doulongvec_minmax,
784 .strategy = &sysctl_intvec,
787 .ctl_name = CTL_UNNUMBERED,
788 .procname = "hung_task_warnings",
789 .data = &sysctl_hung_task_warnings,
790 .maxlen = sizeof(unsigned long),
791 .mode = 0644,
792 .proc_handler = &proc_doulongvec_minmax,
793 .strategy = &sysctl_intvec,
795 #endif
796 #ifdef CONFIG_COMPAT
798 .ctl_name = KERN_COMPAT_LOG,
799 .procname = "compat-log",
800 .data = &compat_log,
801 .maxlen = sizeof (int),
802 .mode = 0644,
803 .proc_handler = &proc_dointvec,
805 #endif
806 #ifdef CONFIG_RT_MUTEXES
808 .ctl_name = KERN_MAX_LOCK_DEPTH,
809 .procname = "max_lock_depth",
810 .data = &max_lock_depth,
811 .maxlen = sizeof(int),
812 .mode = 0644,
813 .proc_handler = &proc_dointvec,
815 #endif
816 #ifdef CONFIG_PROC_FS
818 .ctl_name = CTL_UNNUMBERED,
819 .procname = "maps_protect",
820 .data = &maps_protect,
821 .maxlen = sizeof(int),
822 .mode = 0644,
823 .proc_handler = &proc_dointvec,
825 #endif
827 .ctl_name = CTL_UNNUMBERED,
828 .procname = "poweroff_cmd",
829 .data = &poweroff_cmd,
830 .maxlen = POWEROFF_CMD_PATH_LEN,
831 .mode = 0644,
832 .proc_handler = &proc_dostring,
833 .strategy = &sysctl_string,
835 #ifdef CONFIG_KEYS
837 .ctl_name = CTL_UNNUMBERED,
838 .procname = "keys",
839 .mode = 0555,
840 .child = key_sysctls,
842 #endif
843 #ifdef CONFIG_RCU_TORTURE_TEST
845 .ctl_name = CTL_UNNUMBERED,
846 .procname = "rcutorture_runnable",
847 .data = &rcutorture_runnable,
848 .maxlen = sizeof(int),
849 .mode = 0644,
850 .proc_handler = &proc_dointvec,
852 #endif
854 * NOTE: do not add new entries to this table unless you have read
855 * Documentation/sysctl/ctl_unnumbered.txt
857 { .ctl_name = 0 }
860 static struct ctl_table vm_table[] = {
862 .ctl_name = VM_OVERCOMMIT_MEMORY,
863 .procname = "overcommit_memory",
864 .data = &sysctl_overcommit_memory,
865 .maxlen = sizeof(sysctl_overcommit_memory),
866 .mode = 0644,
867 .proc_handler = &proc_dointvec,
870 .ctl_name = VM_PANIC_ON_OOM,
871 .procname = "panic_on_oom",
872 .data = &sysctl_panic_on_oom,
873 .maxlen = sizeof(sysctl_panic_on_oom),
874 .mode = 0644,
875 .proc_handler = &proc_dointvec,
878 .ctl_name = CTL_UNNUMBERED,
879 .procname = "oom_kill_allocating_task",
880 .data = &sysctl_oom_kill_allocating_task,
881 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
882 .mode = 0644,
883 .proc_handler = &proc_dointvec,
886 .ctl_name = CTL_UNNUMBERED,
887 .procname = "oom_dump_tasks",
888 .data = &sysctl_oom_dump_tasks,
889 .maxlen = sizeof(sysctl_oom_dump_tasks),
890 .mode = 0644,
891 .proc_handler = &proc_dointvec,
894 .ctl_name = VM_OVERCOMMIT_RATIO,
895 .procname = "overcommit_ratio",
896 .data = &sysctl_overcommit_ratio,
897 .maxlen = sizeof(sysctl_overcommit_ratio),
898 .mode = 0644,
899 .proc_handler = &proc_dointvec,
902 .ctl_name = VM_PAGE_CLUSTER,
903 .procname = "page-cluster",
904 .data = &page_cluster,
905 .maxlen = sizeof(int),
906 .mode = 0644,
907 .proc_handler = &proc_dointvec,
910 .ctl_name = VM_DIRTY_BACKGROUND,
911 .procname = "dirty_background_ratio",
912 .data = &dirty_background_ratio,
913 .maxlen = sizeof(dirty_background_ratio),
914 .mode = 0644,
915 .proc_handler = &proc_dointvec_minmax,
916 .strategy = &sysctl_intvec,
917 .extra1 = &zero,
918 .extra2 = &one_hundred,
921 .ctl_name = VM_DIRTY_RATIO,
922 .procname = "dirty_ratio",
923 .data = &vm_dirty_ratio,
924 .maxlen = sizeof(vm_dirty_ratio),
925 .mode = 0644,
926 .proc_handler = &dirty_ratio_handler,
927 .strategy = &sysctl_intvec,
928 .extra1 = &zero,
929 .extra2 = &one_hundred,
932 .procname = "dirty_writeback_centisecs",
933 .data = &dirty_writeback_interval,
934 .maxlen = sizeof(dirty_writeback_interval),
935 .mode = 0644,
936 .proc_handler = &dirty_writeback_centisecs_handler,
939 .procname = "dirty_expire_centisecs",
940 .data = &dirty_expire_interval,
941 .maxlen = sizeof(dirty_expire_interval),
942 .mode = 0644,
943 .proc_handler = &proc_dointvec_userhz_jiffies,
946 .ctl_name = VM_NR_PDFLUSH_THREADS,
947 .procname = "nr_pdflush_threads",
948 .data = &nr_pdflush_threads,
949 .maxlen = sizeof nr_pdflush_threads,
950 .mode = 0444 /* read-only*/,
951 .proc_handler = &proc_dointvec,
954 .ctl_name = VM_SWAPPINESS,
955 .procname = "swappiness",
956 .data = &vm_swappiness,
957 .maxlen = sizeof(vm_swappiness),
958 .mode = 0644,
959 .proc_handler = &proc_dointvec_minmax,
960 .strategy = &sysctl_intvec,
961 .extra1 = &zero,
962 .extra2 = &one_hundred,
964 #ifdef CONFIG_HUGETLB_PAGE
966 .procname = "nr_hugepages",
967 .data = NULL,
968 .maxlen = sizeof(unsigned long),
969 .mode = 0644,
970 .proc_handler = &hugetlb_sysctl_handler,
971 .extra1 = (void *)&hugetlb_zero,
972 .extra2 = (void *)&hugetlb_infinity,
975 .ctl_name = VM_HUGETLB_GROUP,
976 .procname = "hugetlb_shm_group",
977 .data = &sysctl_hugetlb_shm_group,
978 .maxlen = sizeof(gid_t),
979 .mode = 0644,
980 .proc_handler = &proc_dointvec,
983 .ctl_name = CTL_UNNUMBERED,
984 .procname = "hugepages_treat_as_movable",
985 .data = &hugepages_treat_as_movable,
986 .maxlen = sizeof(int),
987 .mode = 0644,
988 .proc_handler = &hugetlb_treat_movable_handler,
991 .ctl_name = CTL_UNNUMBERED,
992 .procname = "nr_overcommit_hugepages",
993 .data = NULL,
994 .maxlen = sizeof(unsigned long),
995 .mode = 0644,
996 .proc_handler = &hugetlb_overcommit_handler,
997 .extra1 = (void *)&hugetlb_zero,
998 .extra2 = (void *)&hugetlb_infinity,
1000 #endif
1002 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
1003 .procname = "lowmem_reserve_ratio",
1004 .data = &sysctl_lowmem_reserve_ratio,
1005 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1006 .mode = 0644,
1007 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
1008 .strategy = &sysctl_intvec,
1011 .ctl_name = VM_DROP_PAGECACHE,
1012 .procname = "drop_caches",
1013 .data = &sysctl_drop_caches,
1014 .maxlen = sizeof(int),
1015 .mode = 0644,
1016 .proc_handler = drop_caches_sysctl_handler,
1017 .strategy = &sysctl_intvec,
1020 .ctl_name = VM_MIN_FREE_KBYTES,
1021 .procname = "min_free_kbytes",
1022 .data = &min_free_kbytes,
1023 .maxlen = sizeof(min_free_kbytes),
1024 .mode = 0644,
1025 .proc_handler = &min_free_kbytes_sysctl_handler,
1026 .strategy = &sysctl_intvec,
1027 .extra1 = &zero,
1030 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
1031 .procname = "percpu_pagelist_fraction",
1032 .data = &percpu_pagelist_fraction,
1033 .maxlen = sizeof(percpu_pagelist_fraction),
1034 .mode = 0644,
1035 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
1036 .strategy = &sysctl_intvec,
1037 .extra1 = &min_percpu_pagelist_fract,
1039 #ifdef CONFIG_MMU
1041 .ctl_name = VM_MAX_MAP_COUNT,
1042 .procname = "max_map_count",
1043 .data = &sysctl_max_map_count,
1044 .maxlen = sizeof(sysctl_max_map_count),
1045 .mode = 0644,
1046 .proc_handler = &proc_dointvec
1048 #endif
1050 .ctl_name = VM_LAPTOP_MODE,
1051 .procname = "laptop_mode",
1052 .data = &laptop_mode,
1053 .maxlen = sizeof(laptop_mode),
1054 .mode = 0644,
1055 .proc_handler = &proc_dointvec_jiffies,
1056 .strategy = &sysctl_jiffies,
1059 .ctl_name = VM_BLOCK_DUMP,
1060 .procname = "block_dump",
1061 .data = &block_dump,
1062 .maxlen = sizeof(block_dump),
1063 .mode = 0644,
1064 .proc_handler = &proc_dointvec,
1065 .strategy = &sysctl_intvec,
1066 .extra1 = &zero,
1069 .ctl_name = VM_VFS_CACHE_PRESSURE,
1070 .procname = "vfs_cache_pressure",
1071 .data = &sysctl_vfs_cache_pressure,
1072 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1073 .mode = 0644,
1074 .proc_handler = &proc_dointvec,
1075 .strategy = &sysctl_intvec,
1076 .extra1 = &zero,
1078 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1080 .ctl_name = VM_LEGACY_VA_LAYOUT,
1081 .procname = "legacy_va_layout",
1082 .data = &sysctl_legacy_va_layout,
1083 .maxlen = sizeof(sysctl_legacy_va_layout),
1084 .mode = 0644,
1085 .proc_handler = &proc_dointvec,
1086 .strategy = &sysctl_intvec,
1087 .extra1 = &zero,
1089 #endif
1090 #ifdef CONFIG_NUMA
1092 .ctl_name = VM_ZONE_RECLAIM_MODE,
1093 .procname = "zone_reclaim_mode",
1094 .data = &zone_reclaim_mode,
1095 .maxlen = sizeof(zone_reclaim_mode),
1096 .mode = 0644,
1097 .proc_handler = &proc_dointvec,
1098 .strategy = &sysctl_intvec,
1099 .extra1 = &zero,
1102 .ctl_name = VM_MIN_UNMAPPED,
1103 .procname = "min_unmapped_ratio",
1104 .data = &sysctl_min_unmapped_ratio,
1105 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1106 .mode = 0644,
1107 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
1108 .strategy = &sysctl_intvec,
1109 .extra1 = &zero,
1110 .extra2 = &one_hundred,
1113 .ctl_name = VM_MIN_SLAB,
1114 .procname = "min_slab_ratio",
1115 .data = &sysctl_min_slab_ratio,
1116 .maxlen = sizeof(sysctl_min_slab_ratio),
1117 .mode = 0644,
1118 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler,
1119 .strategy = &sysctl_intvec,
1120 .extra1 = &zero,
1121 .extra2 = &one_hundred,
1123 #endif
1124 #ifdef CONFIG_SMP
1126 .ctl_name = CTL_UNNUMBERED,
1127 .procname = "stat_interval",
1128 .data = &sysctl_stat_interval,
1129 .maxlen = sizeof(sysctl_stat_interval),
1130 .mode = 0644,
1131 .proc_handler = &proc_dointvec_jiffies,
1132 .strategy = &sysctl_jiffies,
1134 #endif
1135 #ifdef CONFIG_SECURITY
1137 .ctl_name = CTL_UNNUMBERED,
1138 .procname = "mmap_min_addr",
1139 .data = &mmap_min_addr,
1140 .maxlen = sizeof(unsigned long),
1141 .mode = 0644,
1142 .proc_handler = &proc_doulongvec_minmax,
1144 #endif
1145 #ifdef CONFIG_NUMA
1147 .ctl_name = CTL_UNNUMBERED,
1148 .procname = "numa_zonelist_order",
1149 .data = &numa_zonelist_order,
1150 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1151 .mode = 0644,
1152 .proc_handler = &numa_zonelist_order_handler,
1153 .strategy = &sysctl_string,
1155 #endif
1156 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1157 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1159 .ctl_name = VM_VDSO_ENABLED,
1160 .procname = "vdso_enabled",
1161 .data = &vdso_enabled,
1162 .maxlen = sizeof(vdso_enabled),
1163 .mode = 0644,
1164 .proc_handler = &proc_dointvec,
1165 .strategy = &sysctl_intvec,
1166 .extra1 = &zero,
1168 #endif
1169 #ifdef CONFIG_HIGHMEM
1171 .ctl_name = CTL_UNNUMBERED,
1172 .procname = "highmem_is_dirtyable",
1173 .data = &vm_highmem_is_dirtyable,
1174 .maxlen = sizeof(vm_highmem_is_dirtyable),
1175 .mode = 0644,
1176 .proc_handler = &proc_dointvec_minmax,
1177 .strategy = &sysctl_intvec,
1178 .extra1 = &zero,
1179 .extra2 = &one,
1181 #endif
1183 * NOTE: do not add new entries to this table unless you have read
1184 * Documentation/sysctl/ctl_unnumbered.txt
1186 { .ctl_name = 0 }
1189 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1190 static struct ctl_table binfmt_misc_table[] = {
1191 { .ctl_name = 0 }
1193 #endif
1195 static struct ctl_table fs_table[] = {
1197 .ctl_name = FS_NRINODE,
1198 .procname = "inode-nr",
1199 .data = &inodes_stat,
1200 .maxlen = 2*sizeof(int),
1201 .mode = 0444,
1202 .proc_handler = &proc_dointvec,
1205 .ctl_name = FS_STATINODE,
1206 .procname = "inode-state",
1207 .data = &inodes_stat,
1208 .maxlen = 7*sizeof(int),
1209 .mode = 0444,
1210 .proc_handler = &proc_dointvec,
1213 .procname = "file-nr",
1214 .data = &files_stat,
1215 .maxlen = 3*sizeof(int),
1216 .mode = 0444,
1217 .proc_handler = &proc_nr_files,
1220 .ctl_name = FS_MAXFILE,
1221 .procname = "file-max",
1222 .data = &files_stat.max_files,
1223 .maxlen = sizeof(int),
1224 .mode = 0644,
1225 .proc_handler = &proc_dointvec,
1228 .ctl_name = CTL_UNNUMBERED,
1229 .procname = "nr_open",
1230 .data = &sysctl_nr_open,
1231 .maxlen = sizeof(int),
1232 .mode = 0644,
1233 .proc_handler = &proc_dointvec_minmax,
1234 .extra1 = &sysctl_nr_open_min,
1235 .extra2 = &sysctl_nr_open_max,
1238 .ctl_name = FS_DENTRY,
1239 .procname = "dentry-state",
1240 .data = &dentry_stat,
1241 .maxlen = 6*sizeof(int),
1242 .mode = 0444,
1243 .proc_handler = &proc_dointvec,
1246 .ctl_name = FS_OVERFLOWUID,
1247 .procname = "overflowuid",
1248 .data = &fs_overflowuid,
1249 .maxlen = sizeof(int),
1250 .mode = 0644,
1251 .proc_handler = &proc_dointvec_minmax,
1252 .strategy = &sysctl_intvec,
1253 .extra1 = &minolduid,
1254 .extra2 = &maxolduid,
1257 .ctl_name = FS_OVERFLOWGID,
1258 .procname = "overflowgid",
1259 .data = &fs_overflowgid,
1260 .maxlen = sizeof(int),
1261 .mode = 0644,
1262 .proc_handler = &proc_dointvec_minmax,
1263 .strategy = &sysctl_intvec,
1264 .extra1 = &minolduid,
1265 .extra2 = &maxolduid,
1268 .ctl_name = FS_LEASES,
1269 .procname = "leases-enable",
1270 .data = &leases_enable,
1271 .maxlen = sizeof(int),
1272 .mode = 0644,
1273 .proc_handler = &proc_dointvec,
1275 #ifdef CONFIG_DNOTIFY
1277 .ctl_name = FS_DIR_NOTIFY,
1278 .procname = "dir-notify-enable",
1279 .data = &dir_notify_enable,
1280 .maxlen = sizeof(int),
1281 .mode = 0644,
1282 .proc_handler = &proc_dointvec,
1284 #endif
1285 #ifdef CONFIG_MMU
1287 .ctl_name = FS_LEASE_TIME,
1288 .procname = "lease-break-time",
1289 .data = &lease_break_time,
1290 .maxlen = sizeof(int),
1291 .mode = 0644,
1292 .proc_handler = &proc_dointvec_minmax,
1293 .strategy = &sysctl_intvec,
1294 .extra1 = &zero,
1295 .extra2 = &two,
1298 .procname = "aio-nr",
1299 .data = &aio_nr,
1300 .maxlen = sizeof(aio_nr),
1301 .mode = 0444,
1302 .proc_handler = &proc_doulongvec_minmax,
1305 .procname = "aio-max-nr",
1306 .data = &aio_max_nr,
1307 .maxlen = sizeof(aio_max_nr),
1308 .mode = 0644,
1309 .proc_handler = &proc_doulongvec_minmax,
1311 #ifdef CONFIG_INOTIFY_USER
1313 .ctl_name = FS_INOTIFY,
1314 .procname = "inotify",
1315 .mode = 0555,
1316 .child = inotify_table,
1318 #endif
1319 #ifdef CONFIG_EPOLL
1321 .procname = "epoll",
1322 .mode = 0555,
1323 .child = epoll_table,
1325 #endif
1326 #endif
1328 .ctl_name = KERN_SETUID_DUMPABLE,
1329 .procname = "suid_dumpable",
1330 .data = &suid_dumpable,
1331 .maxlen = sizeof(int),
1332 .mode = 0644,
1333 .proc_handler = &proc_dointvec,
1335 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1337 .ctl_name = CTL_UNNUMBERED,
1338 .procname = "binfmt_misc",
1339 .mode = 0555,
1340 .child = binfmt_misc_table,
1342 #endif
1344 * NOTE: do not add new entries to this table unless you have read
1345 * Documentation/sysctl/ctl_unnumbered.txt
1347 { .ctl_name = 0 }
1350 static struct ctl_table debug_table[] = {
1351 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1353 .ctl_name = CTL_UNNUMBERED,
1354 .procname = "exception-trace",
1355 .data = &show_unhandled_signals,
1356 .maxlen = sizeof(int),
1357 .mode = 0644,
1358 .proc_handler = proc_dointvec
1360 #endif
1361 { .ctl_name = 0 }
1364 static struct ctl_table dev_table[] = {
1365 { .ctl_name = 0 }
1368 static DEFINE_SPINLOCK(sysctl_lock);
1370 /* called under sysctl_lock */
1371 static int use_table(struct ctl_table_header *p)
1373 if (unlikely(p->unregistering))
1374 return 0;
1375 p->used++;
1376 return 1;
1379 /* called under sysctl_lock */
1380 static void unuse_table(struct ctl_table_header *p)
1382 if (!--p->used)
1383 if (unlikely(p->unregistering))
1384 complete(p->unregistering);
1387 /* called under sysctl_lock, will reacquire if has to wait */
1388 static void start_unregistering(struct ctl_table_header *p)
1391 * if p->used is 0, nobody will ever touch that entry again;
1392 * we'll eliminate all paths to it before dropping sysctl_lock
1394 if (unlikely(p->used)) {
1395 struct completion wait;
1396 init_completion(&wait);
1397 p->unregistering = &wait;
1398 spin_unlock(&sysctl_lock);
1399 wait_for_completion(&wait);
1400 spin_lock(&sysctl_lock);
1401 } else {
1402 /* anything non-NULL; we'll never dereference it */
1403 p->unregistering = ERR_PTR(-EINVAL);
1406 * do not remove from the list until nobody holds it; walking the
1407 * list in do_sysctl() relies on that.
1409 list_del_init(&p->ctl_entry);
1412 void sysctl_head_get(struct ctl_table_header *head)
1414 spin_lock(&sysctl_lock);
1415 head->count++;
1416 spin_unlock(&sysctl_lock);
1419 void sysctl_head_put(struct ctl_table_header *head)
1421 spin_lock(&sysctl_lock);
1422 if (!--head->count)
1423 kfree(head);
1424 spin_unlock(&sysctl_lock);
1427 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1429 if (!head)
1430 BUG();
1431 spin_lock(&sysctl_lock);
1432 if (!use_table(head))
1433 head = ERR_PTR(-ENOENT);
1434 spin_unlock(&sysctl_lock);
1435 return head;
1438 void sysctl_head_finish(struct ctl_table_header *head)
1440 if (!head)
1441 return;
1442 spin_lock(&sysctl_lock);
1443 unuse_table(head);
1444 spin_unlock(&sysctl_lock);
1447 static struct ctl_table_set *
1448 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1450 struct ctl_table_set *set = &root->default_set;
1451 if (root->lookup)
1452 set = root->lookup(root, namespaces);
1453 return set;
1456 static struct list_head *
1457 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1459 struct ctl_table_set *set = lookup_header_set(root, namespaces);
1460 return &set->list;
1463 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1464 struct ctl_table_header *prev)
1466 struct ctl_table_root *root;
1467 struct list_head *header_list;
1468 struct ctl_table_header *head;
1469 struct list_head *tmp;
1471 spin_lock(&sysctl_lock);
1472 if (prev) {
1473 head = prev;
1474 tmp = &prev->ctl_entry;
1475 unuse_table(prev);
1476 goto next;
1478 tmp = &root_table_header.ctl_entry;
1479 for (;;) {
1480 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1482 if (!use_table(head))
1483 goto next;
1484 spin_unlock(&sysctl_lock);
1485 return head;
1486 next:
1487 root = head->root;
1488 tmp = tmp->next;
1489 header_list = lookup_header_list(root, namespaces);
1490 if (tmp != header_list)
1491 continue;
1493 do {
1494 root = list_entry(root->root_list.next,
1495 struct ctl_table_root, root_list);
1496 if (root == &sysctl_table_root)
1497 goto out;
1498 header_list = lookup_header_list(root, namespaces);
1499 } while (list_empty(header_list));
1500 tmp = header_list->next;
1502 out:
1503 spin_unlock(&sysctl_lock);
1504 return NULL;
1507 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1509 return __sysctl_head_next(current->nsproxy, prev);
1512 void register_sysctl_root(struct ctl_table_root *root)
1514 spin_lock(&sysctl_lock);
1515 list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1516 spin_unlock(&sysctl_lock);
1519 #ifdef CONFIG_SYSCTL_SYSCALL
1520 /* Perform the actual read/write of a sysctl table entry. */
1521 static int do_sysctl_strategy(struct ctl_table_root *root,
1522 struct ctl_table *table,
1523 int __user *name, int nlen,
1524 void __user *oldval, size_t __user *oldlenp,
1525 void __user *newval, size_t newlen)
1527 int op = 0, rc;
1529 if (oldval)
1530 op |= MAY_READ;
1531 if (newval)
1532 op |= MAY_WRITE;
1533 if (sysctl_perm(root, table, op))
1534 return -EPERM;
1536 if (table->strategy) {
1537 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1538 newval, newlen);
1539 if (rc < 0)
1540 return rc;
1541 if (rc > 0)
1542 return 0;
1545 /* If there is no strategy routine, or if the strategy returns
1546 * zero, proceed with automatic r/w */
1547 if (table->data && table->maxlen) {
1548 rc = sysctl_data(table, name, nlen, oldval, oldlenp,
1549 newval, newlen);
1550 if (rc < 0)
1551 return rc;
1553 return 0;
1556 static int parse_table(int __user *name, int nlen,
1557 void __user *oldval, size_t __user *oldlenp,
1558 void __user *newval, size_t newlen,
1559 struct ctl_table_root *root,
1560 struct ctl_table *table)
1562 int n;
1563 repeat:
1564 if (!nlen)
1565 return -ENOTDIR;
1566 if (get_user(n, name))
1567 return -EFAULT;
1568 for ( ; table->ctl_name || table->procname; table++) {
1569 if (!table->ctl_name)
1570 continue;
1571 if (n == table->ctl_name) {
1572 int error;
1573 if (table->child) {
1574 if (sysctl_perm(root, table, MAY_EXEC))
1575 return -EPERM;
1576 name++;
1577 nlen--;
1578 table = table->child;
1579 goto repeat;
1581 error = do_sysctl_strategy(root, table, name, nlen,
1582 oldval, oldlenp,
1583 newval, newlen);
1584 return error;
1587 return -ENOTDIR;
1590 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1591 void __user *newval, size_t newlen)
1593 struct ctl_table_header *head;
1594 int error = -ENOTDIR;
1596 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1597 return -ENOTDIR;
1598 if (oldval) {
1599 int old_len;
1600 if (!oldlenp || get_user(old_len, oldlenp))
1601 return -EFAULT;
1604 for (head = sysctl_head_next(NULL); head;
1605 head = sysctl_head_next(head)) {
1606 error = parse_table(name, nlen, oldval, oldlenp,
1607 newval, newlen,
1608 head->root, head->ctl_table);
1609 if (error != -ENOTDIR) {
1610 sysctl_head_finish(head);
1611 break;
1614 return error;
1617 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
1619 struct __sysctl_args tmp;
1620 int error;
1622 if (copy_from_user(&tmp, args, sizeof(tmp)))
1623 return -EFAULT;
1625 error = deprecated_sysctl_warning(&tmp);
1626 if (error)
1627 goto out;
1629 lock_kernel();
1630 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1631 tmp.newval, tmp.newlen);
1632 unlock_kernel();
1633 out:
1634 return error;
1636 #endif /* CONFIG_SYSCTL_SYSCALL */
1639 * sysctl_perm does NOT grant the superuser all rights automatically, because
1640 * some sysctl variables are readonly even to root.
1643 static int test_perm(int mode, int op)
1645 if (!current->euid)
1646 mode >>= 6;
1647 else if (in_egroup_p(0))
1648 mode >>= 3;
1649 if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1650 return 0;
1651 return -EACCES;
1654 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1656 int error;
1657 int mode;
1659 error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1660 if (error)
1661 return error;
1663 if (root->permissions)
1664 mode = root->permissions(root, current->nsproxy, table);
1665 else
1666 mode = table->mode;
1668 return test_perm(mode, op);
1671 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1673 for (; table->ctl_name || table->procname; table++) {
1674 table->parent = parent;
1675 if (table->child)
1676 sysctl_set_parent(table, table->child);
1680 static __init int sysctl_init(void)
1682 sysctl_set_parent(NULL, root_table);
1683 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1685 int err;
1686 err = sysctl_check_table(current->nsproxy, root_table);
1688 #endif
1689 return 0;
1692 core_initcall(sysctl_init);
1694 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1695 struct ctl_table *table)
1697 struct ctl_table *p;
1698 const char *s = branch->procname;
1700 /* branch should have named subdirectory as its first element */
1701 if (!s || !branch->child)
1702 return NULL;
1704 /* ... and nothing else */
1705 if (branch[1].procname || branch[1].ctl_name)
1706 return NULL;
1708 /* table should contain subdirectory with the same name */
1709 for (p = table; p->procname || p->ctl_name; p++) {
1710 if (!p->child)
1711 continue;
1712 if (p->procname && strcmp(p->procname, s) == 0)
1713 return p;
1715 return NULL;
1718 /* see if attaching q to p would be an improvement */
1719 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1721 struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1722 struct ctl_table *next;
1723 int is_better = 0;
1724 int not_in_parent = !p->attached_by;
1726 while ((next = is_branch_in(by, to)) != NULL) {
1727 if (by == q->attached_by)
1728 is_better = 1;
1729 if (to == p->attached_by)
1730 not_in_parent = 1;
1731 by = by->child;
1732 to = next->child;
1735 if (is_better && not_in_parent) {
1736 q->attached_by = by;
1737 q->attached_to = to;
1738 q->parent = p;
1743 * __register_sysctl_paths - register a sysctl hierarchy
1744 * @root: List of sysctl headers to register on
1745 * @namespaces: Data to compute which lists of sysctl entries are visible
1746 * @path: The path to the directory the sysctl table is in.
1747 * @table: the top-level table structure
1749 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1750 * array. A completely 0 filled entry terminates the table.
1752 * The members of the &struct ctl_table structure are used as follows:
1754 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1755 * must be unique within that level of sysctl
1757 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1758 * enter a sysctl file
1760 * data - a pointer to data for use by proc_handler
1762 * maxlen - the maximum size in bytes of the data
1764 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1766 * child - a pointer to the child sysctl table if this entry is a directory, or
1767 * %NULL.
1769 * proc_handler - the text handler routine (described below)
1771 * strategy - the strategy routine (described below)
1773 * de - for internal use by the sysctl routines
1775 * extra1, extra2 - extra pointers usable by the proc handler routines
1777 * Leaf nodes in the sysctl tree will be represented by a single file
1778 * under /proc; non-leaf nodes will be represented by directories.
1780 * sysctl(2) can automatically manage read and write requests through
1781 * the sysctl table. The data and maxlen fields of the ctl_table
1782 * struct enable minimal validation of the values being written to be
1783 * performed, and the mode field allows minimal authentication.
1785 * More sophisticated management can be enabled by the provision of a
1786 * strategy routine with the table entry. This will be called before
1787 * any automatic read or write of the data is performed.
1789 * The strategy routine may return
1791 * < 0 - Error occurred (error is passed to user process)
1793 * 0 - OK - proceed with automatic read or write.
1795 * > 0 - OK - read or write has been done by the strategy routine, so
1796 * return immediately.
1798 * There must be a proc_handler routine for any terminal nodes
1799 * mirrored under /proc/sys (non-terminals are handled by a built-in
1800 * directory handler). Several default handlers are available to
1801 * cover common cases -
1803 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1804 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1805 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1807 * It is the handler's job to read the input buffer from user memory
1808 * and process it. The handler should return 0 on success.
1810 * This routine returns %NULL on a failure to register, and a pointer
1811 * to the table header on success.
1813 struct ctl_table_header *__register_sysctl_paths(
1814 struct ctl_table_root *root,
1815 struct nsproxy *namespaces,
1816 const struct ctl_path *path, struct ctl_table *table)
1818 struct ctl_table_header *header;
1819 struct ctl_table *new, **prevp;
1820 unsigned int n, npath;
1821 struct ctl_table_set *set;
1823 /* Count the path components */
1824 for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
1828 * For each path component, allocate a 2-element ctl_table array.
1829 * The first array element will be filled with the sysctl entry
1830 * for this, the second will be the sentinel (ctl_name == 0).
1832 * We allocate everything in one go so that we don't have to
1833 * worry about freeing additional memory in unregister_sysctl_table.
1835 header = kzalloc(sizeof(struct ctl_table_header) +
1836 (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
1837 if (!header)
1838 return NULL;
1840 new = (struct ctl_table *) (header + 1);
1842 /* Now connect the dots */
1843 prevp = &header->ctl_table;
1844 for (n = 0; n < npath; ++n, ++path) {
1845 /* Copy the procname */
1846 new->procname = path->procname;
1847 new->ctl_name = path->ctl_name;
1848 new->mode = 0555;
1850 *prevp = new;
1851 prevp = &new->child;
1853 new += 2;
1855 *prevp = table;
1856 header->ctl_table_arg = table;
1858 INIT_LIST_HEAD(&header->ctl_entry);
1859 header->used = 0;
1860 header->unregistering = NULL;
1861 header->root = root;
1862 sysctl_set_parent(NULL, header->ctl_table);
1863 header->count = 1;
1864 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1865 if (sysctl_check_table(namespaces, header->ctl_table)) {
1866 kfree(header);
1867 return NULL;
1869 #endif
1870 spin_lock(&sysctl_lock);
1871 header->set = lookup_header_set(root, namespaces);
1872 header->attached_by = header->ctl_table;
1873 header->attached_to = root_table;
1874 header->parent = &root_table_header;
1875 for (set = header->set; set; set = set->parent) {
1876 struct ctl_table_header *p;
1877 list_for_each_entry(p, &set->list, ctl_entry) {
1878 if (p->unregistering)
1879 continue;
1880 try_attach(p, header);
1883 header->parent->count++;
1884 list_add_tail(&header->ctl_entry, &header->set->list);
1885 spin_unlock(&sysctl_lock);
1887 return header;
1891 * register_sysctl_table_path - register a sysctl table hierarchy
1892 * @path: The path to the directory the sysctl table is in.
1893 * @table: the top-level table structure
1895 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1896 * array. A completely 0 filled entry terminates the table.
1898 * See __register_sysctl_paths for more details.
1900 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1901 struct ctl_table *table)
1903 return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
1904 path, table);
1908 * register_sysctl_table - register a sysctl table hierarchy
1909 * @table: the top-level table structure
1911 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1912 * array. A completely 0 filled entry terminates the table.
1914 * See register_sysctl_paths for more details.
1916 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
1918 static const struct ctl_path null_path[] = { {} };
1920 return register_sysctl_paths(null_path, table);
1924 * unregister_sysctl_table - unregister a sysctl table hierarchy
1925 * @header: the header returned from register_sysctl_table
1927 * Unregisters the sysctl table and all children. proc entries may not
1928 * actually be removed until they are no longer used by anyone.
1930 void unregister_sysctl_table(struct ctl_table_header * header)
1932 might_sleep();
1934 if (header == NULL)
1935 return;
1937 spin_lock(&sysctl_lock);
1938 start_unregistering(header);
1939 if (!--header->parent->count) {
1940 WARN_ON(1);
1941 kfree(header->parent);
1943 if (!--header->count)
1944 kfree(header);
1945 spin_unlock(&sysctl_lock);
1948 int sysctl_is_seen(struct ctl_table_header *p)
1950 struct ctl_table_set *set = p->set;
1951 int res;
1952 spin_lock(&sysctl_lock);
1953 if (p->unregistering)
1954 res = 0;
1955 else if (!set->is_seen)
1956 res = 1;
1957 else
1958 res = set->is_seen(set);
1959 spin_unlock(&sysctl_lock);
1960 return res;
1963 void setup_sysctl_set(struct ctl_table_set *p,
1964 struct ctl_table_set *parent,
1965 int (*is_seen)(struct ctl_table_set *))
1967 INIT_LIST_HEAD(&p->list);
1968 p->parent = parent ? parent : &sysctl_table_root.default_set;
1969 p->is_seen = is_seen;
1972 #else /* !CONFIG_SYSCTL */
1973 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
1975 return NULL;
1978 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1979 struct ctl_table *table)
1981 return NULL;
1984 void unregister_sysctl_table(struct ctl_table_header * table)
1988 void setup_sysctl_set(struct ctl_table_set *p,
1989 struct ctl_table_set *parent,
1990 int (*is_seen)(struct ctl_table_set *))
1994 void sysctl_head_put(struct ctl_table_header *head)
1998 #endif /* CONFIG_SYSCTL */
2001 * /proc/sys support
2004 #ifdef CONFIG_PROC_SYSCTL
2006 static int _proc_do_string(void* data, int maxlen, int write,
2007 struct file *filp, void __user *buffer,
2008 size_t *lenp, loff_t *ppos)
2010 size_t len;
2011 char __user *p;
2012 char c;
2014 if (!data || !maxlen || !*lenp) {
2015 *lenp = 0;
2016 return 0;
2019 if (write) {
2020 len = 0;
2021 p = buffer;
2022 while (len < *lenp) {
2023 if (get_user(c, p++))
2024 return -EFAULT;
2025 if (c == 0 || c == '\n')
2026 break;
2027 len++;
2029 if (len >= maxlen)
2030 len = maxlen-1;
2031 if(copy_from_user(data, buffer, len))
2032 return -EFAULT;
2033 ((char *) data)[len] = 0;
2034 *ppos += *lenp;
2035 } else {
2036 len = strlen(data);
2037 if (len > maxlen)
2038 len = maxlen;
2040 if (*ppos > len) {
2041 *lenp = 0;
2042 return 0;
2045 data += *ppos;
2046 len -= *ppos;
2048 if (len > *lenp)
2049 len = *lenp;
2050 if (len)
2051 if(copy_to_user(buffer, data, len))
2052 return -EFAULT;
2053 if (len < *lenp) {
2054 if(put_user('\n', ((char __user *) buffer) + len))
2055 return -EFAULT;
2056 len++;
2058 *lenp = len;
2059 *ppos += len;
2061 return 0;
2065 * proc_dostring - read a string sysctl
2066 * @table: the sysctl table
2067 * @write: %TRUE if this is a write to the sysctl file
2068 * @filp: the file structure
2069 * @buffer: the user buffer
2070 * @lenp: the size of the user buffer
2071 * @ppos: file position
2073 * Reads/writes a string from/to the user buffer. If the kernel
2074 * buffer provided is not large enough to hold the string, the
2075 * string is truncated. The copied string is %NULL-terminated.
2076 * If the string is being read by the user process, it is copied
2077 * and a newline '\n' is added. It is truncated if the buffer is
2078 * not large enough.
2080 * Returns 0 on success.
2082 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2083 void __user *buffer, size_t *lenp, loff_t *ppos)
2085 return _proc_do_string(table->data, table->maxlen, write, filp,
2086 buffer, lenp, ppos);
2090 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
2091 int *valp,
2092 int write, void *data)
2094 if (write) {
2095 *valp = *negp ? -*lvalp : *lvalp;
2096 } else {
2097 int val = *valp;
2098 if (val < 0) {
2099 *negp = -1;
2100 *lvalp = (unsigned long)-val;
2101 } else {
2102 *negp = 0;
2103 *lvalp = (unsigned long)val;
2106 return 0;
2109 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2110 int write, struct file *filp, void __user *buffer,
2111 size_t *lenp, loff_t *ppos,
2112 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2113 int write, void *data),
2114 void *data)
2116 #define TMPBUFLEN 21
2117 int *i, vleft, first=1, neg, val;
2118 unsigned long lval;
2119 size_t left, len;
2121 char buf[TMPBUFLEN], *p;
2122 char __user *s = buffer;
2124 if (!tbl_data || !table->maxlen || !*lenp ||
2125 (*ppos && !write)) {
2126 *lenp = 0;
2127 return 0;
2130 i = (int *) tbl_data;
2131 vleft = table->maxlen / sizeof(*i);
2132 left = *lenp;
2134 if (!conv)
2135 conv = do_proc_dointvec_conv;
2137 for (; left && vleft--; i++, first=0) {
2138 if (write) {
2139 while (left) {
2140 char c;
2141 if (get_user(c, s))
2142 return -EFAULT;
2143 if (!isspace(c))
2144 break;
2145 left--;
2146 s++;
2148 if (!left)
2149 break;
2150 neg = 0;
2151 len = left;
2152 if (len > sizeof(buf) - 1)
2153 len = sizeof(buf) - 1;
2154 if (copy_from_user(buf, s, len))
2155 return -EFAULT;
2156 buf[len] = 0;
2157 p = buf;
2158 if (*p == '-' && left > 1) {
2159 neg = 1;
2160 p++;
2162 if (*p < '0' || *p > '9')
2163 break;
2165 lval = simple_strtoul(p, &p, 0);
2167 len = p-buf;
2168 if ((len < left) && *p && !isspace(*p))
2169 break;
2170 if (neg)
2171 val = -val;
2172 s += len;
2173 left -= len;
2175 if (conv(&neg, &lval, i, 1, data))
2176 break;
2177 } else {
2178 p = buf;
2179 if (!first)
2180 *p++ = '\t';
2182 if (conv(&neg, &lval, i, 0, data))
2183 break;
2185 sprintf(p, "%s%lu", neg ? "-" : "", lval);
2186 len = strlen(buf);
2187 if (len > left)
2188 len = left;
2189 if(copy_to_user(s, buf, len))
2190 return -EFAULT;
2191 left -= len;
2192 s += len;
2196 if (!write && !first && left) {
2197 if(put_user('\n', s))
2198 return -EFAULT;
2199 left--, s++;
2201 if (write) {
2202 while (left) {
2203 char c;
2204 if (get_user(c, s++))
2205 return -EFAULT;
2206 if (!isspace(c))
2207 break;
2208 left--;
2211 if (write && first)
2212 return -EINVAL;
2213 *lenp -= left;
2214 *ppos += *lenp;
2215 return 0;
2216 #undef TMPBUFLEN
2219 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2220 void __user *buffer, size_t *lenp, loff_t *ppos,
2221 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2222 int write, void *data),
2223 void *data)
2225 return __do_proc_dointvec(table->data, table, write, filp,
2226 buffer, lenp, ppos, conv, data);
2230 * proc_dointvec - read a vector of integers
2231 * @table: the sysctl table
2232 * @write: %TRUE if this is a write to the sysctl file
2233 * @filp: the file structure
2234 * @buffer: the user buffer
2235 * @lenp: the size of the user buffer
2236 * @ppos: file position
2238 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2239 * values from/to the user buffer, treated as an ASCII string.
2241 * Returns 0 on success.
2243 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2244 void __user *buffer, size_t *lenp, loff_t *ppos)
2246 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2247 NULL,NULL);
2250 #define OP_SET 0
2251 #define OP_AND 1
2252 #define OP_OR 2
2254 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
2255 int *valp,
2256 int write, void *data)
2258 int op = *(int *)data;
2259 if (write) {
2260 int val = *negp ? -*lvalp : *lvalp;
2261 switch(op) {
2262 case OP_SET: *valp = val; break;
2263 case OP_AND: *valp &= val; break;
2264 case OP_OR: *valp |= val; break;
2266 } else {
2267 int val = *valp;
2268 if (val < 0) {
2269 *negp = -1;
2270 *lvalp = (unsigned long)-val;
2271 } else {
2272 *negp = 0;
2273 *lvalp = (unsigned long)val;
2276 return 0;
2280 * Taint values can only be increased
2282 static int proc_dointvec_taint(struct ctl_table *table, int write, struct file *filp,
2283 void __user *buffer, size_t *lenp, loff_t *ppos)
2285 int op;
2287 if (write && !capable(CAP_SYS_ADMIN))
2288 return -EPERM;
2290 op = OP_OR;
2291 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2292 do_proc_dointvec_bset_conv,&op);
2295 struct do_proc_dointvec_minmax_conv_param {
2296 int *min;
2297 int *max;
2300 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2301 int *valp,
2302 int write, void *data)
2304 struct do_proc_dointvec_minmax_conv_param *param = data;
2305 if (write) {
2306 int val = *negp ? -*lvalp : *lvalp;
2307 if ((param->min && *param->min > val) ||
2308 (param->max && *param->max < val))
2309 return -EINVAL;
2310 *valp = val;
2311 } else {
2312 int val = *valp;
2313 if (val < 0) {
2314 *negp = -1;
2315 *lvalp = (unsigned long)-val;
2316 } else {
2317 *negp = 0;
2318 *lvalp = (unsigned long)val;
2321 return 0;
2325 * proc_dointvec_minmax - read a vector of integers with min/max values
2326 * @table: the sysctl table
2327 * @write: %TRUE if this is a write to the sysctl file
2328 * @filp: the file structure
2329 * @buffer: the user buffer
2330 * @lenp: the size of the user buffer
2331 * @ppos: file position
2333 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2334 * values from/to the user buffer, treated as an ASCII string.
2336 * This routine will ensure the values are within the range specified by
2337 * table->extra1 (min) and table->extra2 (max).
2339 * Returns 0 on success.
2341 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2342 void __user *buffer, size_t *lenp, loff_t *ppos)
2344 struct do_proc_dointvec_minmax_conv_param param = {
2345 .min = (int *) table->extra1,
2346 .max = (int *) table->extra2,
2348 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2349 do_proc_dointvec_minmax_conv, &param);
2352 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2353 struct file *filp,
2354 void __user *buffer,
2355 size_t *lenp, loff_t *ppos,
2356 unsigned long convmul,
2357 unsigned long convdiv)
2359 #define TMPBUFLEN 21
2360 unsigned long *i, *min, *max, val;
2361 int vleft, first=1, neg;
2362 size_t len, left;
2363 char buf[TMPBUFLEN], *p;
2364 char __user *s = buffer;
2366 if (!data || !table->maxlen || !*lenp ||
2367 (*ppos && !write)) {
2368 *lenp = 0;
2369 return 0;
2372 i = (unsigned long *) data;
2373 min = (unsigned long *) table->extra1;
2374 max = (unsigned long *) table->extra2;
2375 vleft = table->maxlen / sizeof(unsigned long);
2376 left = *lenp;
2378 for (; left && vleft--; i++, min++, max++, first=0) {
2379 if (write) {
2380 while (left) {
2381 char c;
2382 if (get_user(c, s))
2383 return -EFAULT;
2384 if (!isspace(c))
2385 break;
2386 left--;
2387 s++;
2389 if (!left)
2390 break;
2391 neg = 0;
2392 len = left;
2393 if (len > TMPBUFLEN-1)
2394 len = TMPBUFLEN-1;
2395 if (copy_from_user(buf, s, len))
2396 return -EFAULT;
2397 buf[len] = 0;
2398 p = buf;
2399 if (*p == '-' && left > 1) {
2400 neg = 1;
2401 p++;
2403 if (*p < '0' || *p > '9')
2404 break;
2405 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2406 len = p-buf;
2407 if ((len < left) && *p && !isspace(*p))
2408 break;
2409 if (neg)
2410 val = -val;
2411 s += len;
2412 left -= len;
2414 if(neg)
2415 continue;
2416 if ((min && val < *min) || (max && val > *max))
2417 continue;
2418 *i = val;
2419 } else {
2420 p = buf;
2421 if (!first)
2422 *p++ = '\t';
2423 sprintf(p, "%lu", convdiv * (*i) / convmul);
2424 len = strlen(buf);
2425 if (len > left)
2426 len = left;
2427 if(copy_to_user(s, buf, len))
2428 return -EFAULT;
2429 left -= len;
2430 s += len;
2434 if (!write && !first && left) {
2435 if(put_user('\n', s))
2436 return -EFAULT;
2437 left--, s++;
2439 if (write) {
2440 while (left) {
2441 char c;
2442 if (get_user(c, s++))
2443 return -EFAULT;
2444 if (!isspace(c))
2445 break;
2446 left--;
2449 if (write && first)
2450 return -EINVAL;
2451 *lenp -= left;
2452 *ppos += *lenp;
2453 return 0;
2454 #undef TMPBUFLEN
2457 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2458 struct file *filp,
2459 void __user *buffer,
2460 size_t *lenp, loff_t *ppos,
2461 unsigned long convmul,
2462 unsigned long convdiv)
2464 return __do_proc_doulongvec_minmax(table->data, table, write,
2465 filp, buffer, lenp, ppos, convmul, convdiv);
2469 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2470 * @table: the sysctl table
2471 * @write: %TRUE if this is a write to the sysctl file
2472 * @filp: the file structure
2473 * @buffer: the user buffer
2474 * @lenp: the size of the user buffer
2475 * @ppos: file position
2477 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2478 * values from/to the user buffer, treated as an ASCII string.
2480 * This routine will ensure the values are within the range specified by
2481 * table->extra1 (min) and table->extra2 (max).
2483 * Returns 0 on success.
2485 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2486 void __user *buffer, size_t *lenp, loff_t *ppos)
2488 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2492 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2493 * @table: the sysctl table
2494 * @write: %TRUE if this is a write to the sysctl file
2495 * @filp: the file structure
2496 * @buffer: the user buffer
2497 * @lenp: the size of the user buffer
2498 * @ppos: file position
2500 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2501 * values from/to the user buffer, treated as an ASCII string. The values
2502 * are treated as milliseconds, and converted to jiffies when they are stored.
2504 * This routine will ensure the values are within the range specified by
2505 * table->extra1 (min) and table->extra2 (max).
2507 * Returns 0 on success.
2509 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2510 struct file *filp,
2511 void __user *buffer,
2512 size_t *lenp, loff_t *ppos)
2514 return do_proc_doulongvec_minmax(table, write, filp, buffer,
2515 lenp, ppos, HZ, 1000l);
2519 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2520 int *valp,
2521 int write, void *data)
2523 if (write) {
2524 if (*lvalp > LONG_MAX / HZ)
2525 return 1;
2526 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2527 } else {
2528 int val = *valp;
2529 unsigned long lval;
2530 if (val < 0) {
2531 *negp = -1;
2532 lval = (unsigned long)-val;
2533 } else {
2534 *negp = 0;
2535 lval = (unsigned long)val;
2537 *lvalp = lval / HZ;
2539 return 0;
2542 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2543 int *valp,
2544 int write, void *data)
2546 if (write) {
2547 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2548 return 1;
2549 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2550 } else {
2551 int val = *valp;
2552 unsigned long lval;
2553 if (val < 0) {
2554 *negp = -1;
2555 lval = (unsigned long)-val;
2556 } else {
2557 *negp = 0;
2558 lval = (unsigned long)val;
2560 *lvalp = jiffies_to_clock_t(lval);
2562 return 0;
2565 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2566 int *valp,
2567 int write, void *data)
2569 if (write) {
2570 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2571 } else {
2572 int val = *valp;
2573 unsigned long lval;
2574 if (val < 0) {
2575 *negp = -1;
2576 lval = (unsigned long)-val;
2577 } else {
2578 *negp = 0;
2579 lval = (unsigned long)val;
2581 *lvalp = jiffies_to_msecs(lval);
2583 return 0;
2587 * proc_dointvec_jiffies - read a vector of integers as seconds
2588 * @table: the sysctl table
2589 * @write: %TRUE if this is a write to the sysctl file
2590 * @filp: the file structure
2591 * @buffer: the user buffer
2592 * @lenp: the size of the user buffer
2593 * @ppos: file position
2595 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2596 * values from/to the user buffer, treated as an ASCII string.
2597 * The values read are assumed to be in seconds, and are converted into
2598 * jiffies.
2600 * Returns 0 on success.
2602 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2603 void __user *buffer, size_t *lenp, loff_t *ppos)
2605 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2606 do_proc_dointvec_jiffies_conv,NULL);
2610 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2611 * @table: the sysctl table
2612 * @write: %TRUE if this is a write to the sysctl file
2613 * @filp: the file structure
2614 * @buffer: the user buffer
2615 * @lenp: the size of the user buffer
2616 * @ppos: pointer to the file position
2618 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2619 * values from/to the user buffer, treated as an ASCII string.
2620 * The values read are assumed to be in 1/USER_HZ seconds, and
2621 * are converted into jiffies.
2623 * Returns 0 on success.
2625 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2626 void __user *buffer, size_t *lenp, loff_t *ppos)
2628 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2629 do_proc_dointvec_userhz_jiffies_conv,NULL);
2633 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2634 * @table: the sysctl table
2635 * @write: %TRUE if this is a write to the sysctl file
2636 * @filp: the file structure
2637 * @buffer: the user buffer
2638 * @lenp: the size of the user buffer
2639 * @ppos: file position
2640 * @ppos: the current position in the file
2642 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2643 * values from/to the user buffer, treated as an ASCII string.
2644 * The values read are assumed to be in 1/1000 seconds, and
2645 * are converted into jiffies.
2647 * Returns 0 on success.
2649 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2650 void __user *buffer, size_t *lenp, loff_t *ppos)
2652 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2653 do_proc_dointvec_ms_jiffies_conv, NULL);
2656 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2657 void __user *buffer, size_t *lenp, loff_t *ppos)
2659 struct pid *new_pid;
2660 pid_t tmp;
2661 int r;
2663 tmp = pid_vnr(cad_pid);
2665 r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2666 lenp, ppos, NULL, NULL);
2667 if (r || !write)
2668 return r;
2670 new_pid = find_get_pid(tmp);
2671 if (!new_pid)
2672 return -ESRCH;
2674 put_pid(xchg(&cad_pid, new_pid));
2675 return 0;
2678 #else /* CONFIG_PROC_FS */
2680 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2681 void __user *buffer, size_t *lenp, loff_t *ppos)
2683 return -ENOSYS;
2686 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2687 void __user *buffer, size_t *lenp, loff_t *ppos)
2689 return -ENOSYS;
2692 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2693 void __user *buffer, size_t *lenp, loff_t *ppos)
2695 return -ENOSYS;
2698 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2699 void __user *buffer, size_t *lenp, loff_t *ppos)
2701 return -ENOSYS;
2704 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2705 void __user *buffer, size_t *lenp, loff_t *ppos)
2707 return -ENOSYS;
2710 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2711 void __user *buffer, size_t *lenp, loff_t *ppos)
2713 return -ENOSYS;
2716 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2717 void __user *buffer, size_t *lenp, loff_t *ppos)
2719 return -ENOSYS;
2722 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2723 struct file *filp,
2724 void __user *buffer,
2725 size_t *lenp, loff_t *ppos)
2727 return -ENOSYS;
2731 #endif /* CONFIG_PROC_FS */
2734 #ifdef CONFIG_SYSCTL_SYSCALL
2736 * General sysctl support routines
2739 /* The generic sysctl data routine (used if no strategy routine supplied) */
2740 int sysctl_data(struct ctl_table *table, int __user *name, int nlen,
2741 void __user *oldval, size_t __user *oldlenp,
2742 void __user *newval, size_t newlen)
2744 size_t len;
2746 /* Get out of I don't have a variable */
2747 if (!table->data || !table->maxlen)
2748 return -ENOTDIR;
2750 if (oldval && oldlenp) {
2751 if (get_user(len, oldlenp))
2752 return -EFAULT;
2753 if (len) {
2754 if (len > table->maxlen)
2755 len = table->maxlen;
2756 if (copy_to_user(oldval, table->data, len))
2757 return -EFAULT;
2758 if (put_user(len, oldlenp))
2759 return -EFAULT;
2763 if (newval && newlen) {
2764 if (newlen > table->maxlen)
2765 newlen = table->maxlen;
2767 if (copy_from_user(table->data, newval, newlen))
2768 return -EFAULT;
2770 return 1;
2773 /* The generic string strategy routine: */
2774 int sysctl_string(struct ctl_table *table, int __user *name, int nlen,
2775 void __user *oldval, size_t __user *oldlenp,
2776 void __user *newval, size_t newlen)
2778 if (!table->data || !table->maxlen)
2779 return -ENOTDIR;
2781 if (oldval && oldlenp) {
2782 size_t bufsize;
2783 if (get_user(bufsize, oldlenp))
2784 return -EFAULT;
2785 if (bufsize) {
2786 size_t len = strlen(table->data), copied;
2788 /* This shouldn't trigger for a well-formed sysctl */
2789 if (len > table->maxlen)
2790 len = table->maxlen;
2792 /* Copy up to a max of bufsize-1 bytes of the string */
2793 copied = (len >= bufsize) ? bufsize - 1 : len;
2795 if (copy_to_user(oldval, table->data, copied) ||
2796 put_user(0, (char __user *)(oldval + copied)))
2797 return -EFAULT;
2798 if (put_user(len, oldlenp))
2799 return -EFAULT;
2802 if (newval && newlen) {
2803 size_t len = newlen;
2804 if (len > table->maxlen)
2805 len = table->maxlen;
2806 if(copy_from_user(table->data, newval, len))
2807 return -EFAULT;
2808 if (len == table->maxlen)
2809 len--;
2810 ((char *) table->data)[len] = 0;
2812 return 1;
2816 * This function makes sure that all of the integers in the vector
2817 * are between the minimum and maximum values given in the arrays
2818 * table->extra1 and table->extra2, respectively.
2820 int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen,
2821 void __user *oldval, size_t __user *oldlenp,
2822 void __user *newval, size_t newlen)
2825 if (newval && newlen) {
2826 int __user *vec = (int __user *) newval;
2827 int *min = (int *) table->extra1;
2828 int *max = (int *) table->extra2;
2829 size_t length;
2830 int i;
2832 if (newlen % sizeof(int) != 0)
2833 return -EINVAL;
2835 if (!table->extra1 && !table->extra2)
2836 return 0;
2838 if (newlen > table->maxlen)
2839 newlen = table->maxlen;
2840 length = newlen / sizeof(int);
2842 for (i = 0; i < length; i++) {
2843 int value;
2844 if (get_user(value, vec + i))
2845 return -EFAULT;
2846 if (min && value < min[i])
2847 return -EINVAL;
2848 if (max && value > max[i])
2849 return -EINVAL;
2852 return 0;
2855 /* Strategy function to convert jiffies to seconds */
2856 int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen,
2857 void __user *oldval, size_t __user *oldlenp,
2858 void __user *newval, size_t newlen)
2860 if (oldval && oldlenp) {
2861 size_t olen;
2863 if (get_user(olen, oldlenp))
2864 return -EFAULT;
2865 if (olen) {
2866 int val;
2868 if (olen < sizeof(int))
2869 return -EINVAL;
2871 val = *(int *)(table->data) / HZ;
2872 if (put_user(val, (int __user *)oldval))
2873 return -EFAULT;
2874 if (put_user(sizeof(int), oldlenp))
2875 return -EFAULT;
2878 if (newval && newlen) {
2879 int new;
2880 if (newlen != sizeof(int))
2881 return -EINVAL;
2882 if (get_user(new, (int __user *)newval))
2883 return -EFAULT;
2884 *(int *)(table->data) = new*HZ;
2886 return 1;
2889 /* Strategy function to convert jiffies to seconds */
2890 int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen,
2891 void __user *oldval, size_t __user *oldlenp,
2892 void __user *newval, size_t newlen)
2894 if (oldval && oldlenp) {
2895 size_t olen;
2897 if (get_user(olen, oldlenp))
2898 return -EFAULT;
2899 if (olen) {
2900 int val;
2902 if (olen < sizeof(int))
2903 return -EINVAL;
2905 val = jiffies_to_msecs(*(int *)(table->data));
2906 if (put_user(val, (int __user *)oldval))
2907 return -EFAULT;
2908 if (put_user(sizeof(int), oldlenp))
2909 return -EFAULT;
2912 if (newval && newlen) {
2913 int new;
2914 if (newlen != sizeof(int))
2915 return -EINVAL;
2916 if (get_user(new, (int __user *)newval))
2917 return -EFAULT;
2918 *(int *)(table->data) = msecs_to_jiffies(new);
2920 return 1;
2925 #else /* CONFIG_SYSCTL_SYSCALL */
2928 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
2930 struct __sysctl_args tmp;
2931 int error;
2933 if (copy_from_user(&tmp, args, sizeof(tmp)))
2934 return -EFAULT;
2936 error = deprecated_sysctl_warning(&tmp);
2938 /* If no error reading the parameters then just -ENOSYS ... */
2939 if (!error)
2940 error = -ENOSYS;
2942 return error;
2945 int sysctl_data(struct ctl_table *table, int __user *name, int nlen,
2946 void __user *oldval, size_t __user *oldlenp,
2947 void __user *newval, size_t newlen)
2949 return -ENOSYS;
2952 int sysctl_string(struct ctl_table *table, int __user *name, int nlen,
2953 void __user *oldval, size_t __user *oldlenp,
2954 void __user *newval, size_t newlen)
2956 return -ENOSYS;
2959 int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen,
2960 void __user *oldval, size_t __user *oldlenp,
2961 void __user *newval, size_t newlen)
2963 return -ENOSYS;
2966 int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen,
2967 void __user *oldval, size_t __user *oldlenp,
2968 void __user *newval, size_t newlen)
2970 return -ENOSYS;
2973 int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen,
2974 void __user *oldval, size_t __user *oldlenp,
2975 void __user *newval, size_t newlen)
2977 return -ENOSYS;
2980 #endif /* CONFIG_SYSCTL_SYSCALL */
2982 static int deprecated_sysctl_warning(struct __sysctl_args *args)
2984 static int msg_count;
2985 int name[CTL_MAXNAME];
2986 int i;
2988 /* Check args->nlen. */
2989 if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
2990 return -ENOTDIR;
2992 /* Read in the sysctl name for better debug message logging */
2993 for (i = 0; i < args->nlen; i++)
2994 if (get_user(name[i], args->name + i))
2995 return -EFAULT;
2997 /* Ignore accesses to kernel.version */
2998 if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
2999 return 0;
3001 if (msg_count < 5) {
3002 msg_count++;
3003 printk(KERN_INFO
3004 "warning: process `%s' used the deprecated sysctl "
3005 "system call with ", current->comm);
3006 for (i = 0; i < args->nlen; i++)
3007 printk("%d.", name[i]);
3008 printk("\n");
3010 return 0;
3014 * No sense putting this after each symbol definition, twice,
3015 * exception granted :-)
3017 EXPORT_SYMBOL(proc_dointvec);
3018 EXPORT_SYMBOL(proc_dointvec_jiffies);
3019 EXPORT_SYMBOL(proc_dointvec_minmax);
3020 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3021 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3022 EXPORT_SYMBOL(proc_dostring);
3023 EXPORT_SYMBOL(proc_doulongvec_minmax);
3024 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3025 EXPORT_SYMBOL(register_sysctl_table);
3026 EXPORT_SYMBOL(register_sysctl_paths);
3027 EXPORT_SYMBOL(sysctl_intvec);
3028 EXPORT_SYMBOL(sysctl_jiffies);
3029 EXPORT_SYMBOL(sysctl_ms_jiffies);
3030 EXPORT_SYMBOL(sysctl_string);
3031 EXPORT_SYMBOL(sysctl_data);
3032 EXPORT_SYMBOL(unregister_sysctl_table);