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
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
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>
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>
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/nfs_fs.h>
47 #include <linux/acpi.h>
48 #include <linux/reboot.h>
50 #include <asm/uaccess.h>
51 #include <asm/processor.h>
55 #include <asm/stacktrace.h>
59 static int deprecated_sysctl_warning(struct __sysctl_args *args);
61 #if defined(CONFIG_SYSCTL)
63 /* External variables not in a header file. */
65 extern int print_fatal_signals;
66 extern int sysctl_overcommit_memory;
67 extern int sysctl_overcommit_ratio;
68 extern int sysctl_panic_on_oom;
69 extern int sysctl_oom_kill_allocating_task;
70 extern int sysctl_oom_dump_tasks;
71 extern int max_threads;
72 extern int core_uses_pid;
73 extern int suid_dumpable;
74 extern char core_pattern[];
76 extern int min_free_kbytes;
77 extern int pid_max_min, pid_max_max;
78 extern int sysctl_drop_caches;
79 extern int percpu_pagelist_fraction;
80 extern int compat_log;
81 extern int maps_protect;
82 extern int sysctl_stat_interval;
83 extern int latencytop_enabled;
84 extern int sysctl_nr_open_min, sysctl_nr_open_max;
86 /* Constants used for minimum and maximum */
87 #if defined(CONFIG_DETECT_SOFTLOCKUP) || defined(CONFIG_HIGHMEM)
91 #ifdef CONFIG_DETECT_SOFTLOCKUP
92 static int sixty = 60;
100 static int one_hundred = 100;
102 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
103 static int maxolduid = 65535;
104 static int minolduid;
105 static int min_percpu_pagelist_fract = 8;
107 static int ngroups_max = NGROUPS_MAX;
110 extern char modprobe_path[];
112 #ifdef CONFIG_CHR_DEV_SG
113 extern int sg_big_buff;
117 extern char reboot_command [];
118 extern int stop_a_enabled;
119 extern int scons_pwroff;
123 extern int pwrsw_enabled;
124 extern int unaligned_enabled;
128 #ifdef CONFIG_MATHEMU
129 extern int sysctl_ieee_emulation_warnings;
131 extern int sysctl_userprocess_debug;
132 extern int spin_retry;
135 extern int sysctl_hz_timer;
137 #ifdef CONFIG_BSD_PROCESS_ACCT
138 extern int acct_parm[];
142 extern int no_unaligned_warning;
145 #ifdef CONFIG_RT_MUTEXES
146 extern int max_lock_depth;
149 #ifdef CONFIG_PROC_SYSCTL
150 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
151 void __user *buffer, size_t *lenp, loff_t *ppos);
152 static int proc_dointvec_taint(struct ctl_table *table, int write, struct file *filp,
153 void __user *buffer, size_t *lenp, loff_t *ppos);
156 static struct ctl_table root_table[];
157 static struct ctl_table_root sysctl_table_root;
158 static struct ctl_table_header root_table_header = {
159 .ctl_table = root_table,
160 .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.header_list),
161 .root = &sysctl_table_root,
163 static struct ctl_table_root sysctl_table_root = {
164 .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
165 .header_list = LIST_HEAD_INIT(root_table_header.ctl_entry),
168 static struct ctl_table kern_table[];
169 static struct ctl_table vm_table[];
170 static struct ctl_table fs_table[];
171 static struct ctl_table debug_table[];
172 static struct ctl_table dev_table[];
173 extern struct ctl_table random_table[];
174 #ifdef CONFIG_INOTIFY_USER
175 extern struct ctl_table inotify_table[];
178 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
179 int sysctl_legacy_va_layout;
182 extern int prove_locking;
183 extern int lock_stat;
185 /* The default sysctl tables: */
187 static struct ctl_table root_table[] = {
189 .ctl_name = CTL_KERN,
190 .procname = "kernel",
207 .ctl_name = CTL_DEBUG,
210 .child = debug_table,
219 * NOTE: do not add new entries to this table unless you have read
220 * Documentation/sysctl/ctl_unnumbered.txt
225 #ifdef CONFIG_SCHED_DEBUG
226 static int min_sched_granularity_ns = 100000; /* 100 usecs */
227 static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
228 static int min_wakeup_granularity_ns; /* 0 usecs */
229 static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
232 static struct ctl_table kern_table[] = {
233 #ifdef CONFIG_SCHED_DEBUG
235 .ctl_name = CTL_UNNUMBERED,
236 .procname = "sched_min_granularity_ns",
237 .data = &sysctl_sched_min_granularity,
238 .maxlen = sizeof(unsigned int),
240 .proc_handler = &sched_nr_latency_handler,
241 .strategy = &sysctl_intvec,
242 .extra1 = &min_sched_granularity_ns,
243 .extra2 = &max_sched_granularity_ns,
246 .ctl_name = CTL_UNNUMBERED,
247 .procname = "sched_latency_ns",
248 .data = &sysctl_sched_latency,
249 .maxlen = sizeof(unsigned int),
251 .proc_handler = &sched_nr_latency_handler,
252 .strategy = &sysctl_intvec,
253 .extra1 = &min_sched_granularity_ns,
254 .extra2 = &max_sched_granularity_ns,
257 .ctl_name = CTL_UNNUMBERED,
258 .procname = "sched_wakeup_granularity_ns",
259 .data = &sysctl_sched_wakeup_granularity,
260 .maxlen = sizeof(unsigned int),
262 .proc_handler = &proc_dointvec_minmax,
263 .strategy = &sysctl_intvec,
264 .extra1 = &min_wakeup_granularity_ns,
265 .extra2 = &max_wakeup_granularity_ns,
268 .ctl_name = CTL_UNNUMBERED,
269 .procname = "sched_shares_ratelimit",
270 .data = &sysctl_sched_shares_ratelimit,
271 .maxlen = sizeof(unsigned int),
273 .proc_handler = &proc_dointvec,
276 .ctl_name = CTL_UNNUMBERED,
277 .procname = "sched_child_runs_first",
278 .data = &sysctl_sched_child_runs_first,
279 .maxlen = sizeof(unsigned int),
281 .proc_handler = &proc_dointvec,
284 .ctl_name = CTL_UNNUMBERED,
285 .procname = "sched_features",
286 .data = &sysctl_sched_features,
287 .maxlen = sizeof(unsigned int),
289 .proc_handler = &proc_dointvec,
292 .ctl_name = CTL_UNNUMBERED,
293 .procname = "sched_migration_cost",
294 .data = &sysctl_sched_migration_cost,
295 .maxlen = sizeof(unsigned int),
297 .proc_handler = &proc_dointvec,
300 .ctl_name = CTL_UNNUMBERED,
301 .procname = "sched_nr_migrate",
302 .data = &sysctl_sched_nr_migrate,
303 .maxlen = sizeof(unsigned int),
305 .proc_handler = &proc_dointvec,
309 .ctl_name = CTL_UNNUMBERED,
310 .procname = "sched_rt_period_us",
311 .data = &sysctl_sched_rt_period,
312 .maxlen = sizeof(unsigned int),
314 .proc_handler = &sched_rt_handler,
317 .ctl_name = CTL_UNNUMBERED,
318 .procname = "sched_rt_runtime_us",
319 .data = &sysctl_sched_rt_runtime,
320 .maxlen = sizeof(int),
322 .proc_handler = &sched_rt_handler,
325 .ctl_name = CTL_UNNUMBERED,
326 .procname = "sched_compat_yield",
327 .data = &sysctl_sched_compat_yield,
328 .maxlen = sizeof(unsigned int),
330 .proc_handler = &proc_dointvec,
332 #ifdef CONFIG_PROVE_LOCKING
334 .ctl_name = CTL_UNNUMBERED,
335 .procname = "prove_locking",
336 .data = &prove_locking,
337 .maxlen = sizeof(int),
339 .proc_handler = &proc_dointvec,
342 #ifdef CONFIG_LOCK_STAT
344 .ctl_name = CTL_UNNUMBERED,
345 .procname = "lock_stat",
347 .maxlen = sizeof(int),
349 .proc_handler = &proc_dointvec,
353 .ctl_name = KERN_PANIC,
355 .data = &panic_timeout,
356 .maxlen = sizeof(int),
358 .proc_handler = &proc_dointvec,
361 .ctl_name = KERN_CORE_USES_PID,
362 .procname = "core_uses_pid",
363 .data = &core_uses_pid,
364 .maxlen = sizeof(int),
366 .proc_handler = &proc_dointvec,
369 .ctl_name = KERN_CORE_PATTERN,
370 .procname = "core_pattern",
371 .data = core_pattern,
372 .maxlen = CORENAME_MAX_SIZE,
374 .proc_handler = &proc_dostring,
375 .strategy = &sysctl_string,
377 #ifdef CONFIG_PROC_SYSCTL
379 .procname = "tainted",
381 .maxlen = sizeof(int),
383 .proc_handler = &proc_dointvec_taint,
386 #ifdef CONFIG_LATENCYTOP
388 .procname = "latencytop",
389 .data = &latencytop_enabled,
390 .maxlen = sizeof(int),
392 .proc_handler = &proc_dointvec,
395 #ifdef CONFIG_BLK_DEV_INITRD
397 .ctl_name = KERN_REALROOTDEV,
398 .procname = "real-root-dev",
399 .data = &real_root_dev,
400 .maxlen = sizeof(int),
402 .proc_handler = &proc_dointvec,
406 .ctl_name = CTL_UNNUMBERED,
407 .procname = "print-fatal-signals",
408 .data = &print_fatal_signals,
409 .maxlen = sizeof(int),
411 .proc_handler = &proc_dointvec,
415 .ctl_name = KERN_SPARC_REBOOT,
416 .procname = "reboot-cmd",
417 .data = reboot_command,
420 .proc_handler = &proc_dostring,
421 .strategy = &sysctl_string,
424 .ctl_name = KERN_SPARC_STOP_A,
425 .procname = "stop-a",
426 .data = &stop_a_enabled,
427 .maxlen = sizeof (int),
429 .proc_handler = &proc_dointvec,
432 .ctl_name = KERN_SPARC_SCONS_PWROFF,
433 .procname = "scons-poweroff",
434 .data = &scons_pwroff,
435 .maxlen = sizeof (int),
437 .proc_handler = &proc_dointvec,
442 .ctl_name = KERN_HPPA_PWRSW,
443 .procname = "soft-power",
444 .data = &pwrsw_enabled,
445 .maxlen = sizeof (int),
447 .proc_handler = &proc_dointvec,
450 .ctl_name = KERN_HPPA_UNALIGNED,
451 .procname = "unaligned-trap",
452 .data = &unaligned_enabled,
453 .maxlen = sizeof (int),
455 .proc_handler = &proc_dointvec,
459 .ctl_name = KERN_CTLALTDEL,
460 .procname = "ctrl-alt-del",
462 .maxlen = sizeof(int),
464 .proc_handler = &proc_dointvec,
468 .ctl_name = KERN_MODPROBE,
469 .procname = "modprobe",
470 .data = &modprobe_path,
471 .maxlen = KMOD_PATH_LEN,
473 .proc_handler = &proc_dostring,
474 .strategy = &sysctl_string,
477 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
479 .ctl_name = KERN_HOTPLUG,
480 .procname = "hotplug",
481 .data = &uevent_helper,
482 .maxlen = UEVENT_HELPER_PATH_LEN,
484 .proc_handler = &proc_dostring,
485 .strategy = &sysctl_string,
488 #ifdef CONFIG_CHR_DEV_SG
490 .ctl_name = KERN_SG_BIG_BUFF,
491 .procname = "sg-big-buff",
492 .data = &sg_big_buff,
493 .maxlen = sizeof (int),
495 .proc_handler = &proc_dointvec,
498 #ifdef CONFIG_BSD_PROCESS_ACCT
500 .ctl_name = KERN_ACCT,
503 .maxlen = 3*sizeof(int),
505 .proc_handler = &proc_dointvec,
508 #ifdef CONFIG_MAGIC_SYSRQ
510 .ctl_name = KERN_SYSRQ,
512 .data = &__sysrq_enabled,
513 .maxlen = sizeof (int),
515 .proc_handler = &proc_dointvec,
518 #ifdef CONFIG_PROC_SYSCTL
520 .procname = "cad_pid",
522 .maxlen = sizeof (int),
524 .proc_handler = &proc_do_cad_pid,
528 .ctl_name = KERN_MAX_THREADS,
529 .procname = "threads-max",
530 .data = &max_threads,
531 .maxlen = sizeof(int),
533 .proc_handler = &proc_dointvec,
536 .ctl_name = KERN_RANDOM,
537 .procname = "random",
539 .child = random_table,
542 .ctl_name = KERN_OVERFLOWUID,
543 .procname = "overflowuid",
544 .data = &overflowuid,
545 .maxlen = sizeof(int),
547 .proc_handler = &proc_dointvec_minmax,
548 .strategy = &sysctl_intvec,
549 .extra1 = &minolduid,
550 .extra2 = &maxolduid,
553 .ctl_name = KERN_OVERFLOWGID,
554 .procname = "overflowgid",
555 .data = &overflowgid,
556 .maxlen = sizeof(int),
558 .proc_handler = &proc_dointvec_minmax,
559 .strategy = &sysctl_intvec,
560 .extra1 = &minolduid,
561 .extra2 = &maxolduid,
564 #ifdef CONFIG_MATHEMU
566 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
567 .procname = "ieee_emulation_warnings",
568 .data = &sysctl_ieee_emulation_warnings,
569 .maxlen = sizeof(int),
571 .proc_handler = &proc_dointvec,
574 #ifdef CONFIG_NO_IDLE_HZ
576 .ctl_name = KERN_HZ_TIMER,
577 .procname = "hz_timer",
578 .data = &sysctl_hz_timer,
579 .maxlen = sizeof(int),
581 .proc_handler = &proc_dointvec,
585 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
586 .procname = "userprocess_debug",
587 .data = &sysctl_userprocess_debug,
588 .maxlen = sizeof(int),
590 .proc_handler = &proc_dointvec,
594 .ctl_name = KERN_PIDMAX,
595 .procname = "pid_max",
597 .maxlen = sizeof (int),
599 .proc_handler = &proc_dointvec_minmax,
600 .strategy = sysctl_intvec,
601 .extra1 = &pid_max_min,
602 .extra2 = &pid_max_max,
605 .ctl_name = KERN_PANIC_ON_OOPS,
606 .procname = "panic_on_oops",
607 .data = &panic_on_oops,
608 .maxlen = sizeof(int),
610 .proc_handler = &proc_dointvec,
612 #if defined CONFIG_PRINTK
614 .ctl_name = KERN_PRINTK,
615 .procname = "printk",
616 .data = &console_loglevel,
617 .maxlen = 4*sizeof(int),
619 .proc_handler = &proc_dointvec,
622 .ctl_name = KERN_PRINTK_RATELIMIT,
623 .procname = "printk_ratelimit",
624 .data = &printk_ratelimit_jiffies,
625 .maxlen = sizeof(int),
627 .proc_handler = &proc_dointvec_jiffies,
628 .strategy = &sysctl_jiffies,
631 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
632 .procname = "printk_ratelimit_burst",
633 .data = &printk_ratelimit_burst,
634 .maxlen = sizeof(int),
636 .proc_handler = &proc_dointvec,
640 .ctl_name = KERN_NGROUPS_MAX,
641 .procname = "ngroups_max",
642 .data = &ngroups_max,
643 .maxlen = sizeof (int),
645 .proc_handler = &proc_dointvec,
647 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
649 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
650 .procname = "unknown_nmi_panic",
651 .data = &unknown_nmi_panic,
652 .maxlen = sizeof (int),
654 .proc_handler = &proc_dointvec,
657 .procname = "nmi_watchdog",
658 .data = &nmi_watchdog_enabled,
659 .maxlen = sizeof (int),
661 .proc_handler = &proc_nmi_enabled,
664 #if defined(CONFIG_X86)
666 .ctl_name = KERN_PANIC_ON_NMI,
667 .procname = "panic_on_unrecovered_nmi",
668 .data = &panic_on_unrecovered_nmi,
669 .maxlen = sizeof(int),
671 .proc_handler = &proc_dointvec,
674 .ctl_name = KERN_BOOTLOADER_TYPE,
675 .procname = "bootloader_type",
676 .data = &bootloader_type,
677 .maxlen = sizeof (int),
679 .proc_handler = &proc_dointvec,
682 .ctl_name = CTL_UNNUMBERED,
683 .procname = "kstack_depth_to_print",
684 .data = &kstack_depth_to_print,
685 .maxlen = sizeof(int),
687 .proc_handler = &proc_dointvec,
690 .ctl_name = CTL_UNNUMBERED,
691 .procname = "io_delay_type",
692 .data = &io_delay_type,
693 .maxlen = sizeof(int),
695 .proc_handler = &proc_dointvec,
698 #if defined(CONFIG_MMU)
700 .ctl_name = KERN_RANDOMIZE,
701 .procname = "randomize_va_space",
702 .data = &randomize_va_space,
703 .maxlen = sizeof(int),
705 .proc_handler = &proc_dointvec,
708 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
710 .ctl_name = KERN_SPIN_RETRY,
711 .procname = "spin_retry",
713 .maxlen = sizeof (int),
715 .proc_handler = &proc_dointvec,
718 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
720 .procname = "acpi_video_flags",
721 .data = &acpi_realmode_flags,
722 .maxlen = sizeof (unsigned long),
724 .proc_handler = &proc_doulongvec_minmax,
729 .ctl_name = KERN_IA64_UNALIGNED,
730 .procname = "ignore-unaligned-usertrap",
731 .data = &no_unaligned_warning,
732 .maxlen = sizeof (int),
734 .proc_handler = &proc_dointvec,
737 #ifdef CONFIG_DETECT_SOFTLOCKUP
739 .ctl_name = CTL_UNNUMBERED,
740 .procname = "softlockup_thresh",
741 .data = &softlockup_thresh,
742 .maxlen = sizeof(unsigned long),
744 .proc_handler = &proc_doulongvec_minmax,
745 .strategy = &sysctl_intvec,
750 .ctl_name = CTL_UNNUMBERED,
751 .procname = "hung_task_check_count",
752 .data = &sysctl_hung_task_check_count,
753 .maxlen = sizeof(unsigned long),
755 .proc_handler = &proc_doulongvec_minmax,
756 .strategy = &sysctl_intvec,
759 .ctl_name = CTL_UNNUMBERED,
760 .procname = "hung_task_timeout_secs",
761 .data = &sysctl_hung_task_timeout_secs,
762 .maxlen = sizeof(unsigned long),
764 .proc_handler = &proc_doulongvec_minmax,
765 .strategy = &sysctl_intvec,
768 .ctl_name = CTL_UNNUMBERED,
769 .procname = "hung_task_warnings",
770 .data = &sysctl_hung_task_warnings,
771 .maxlen = sizeof(unsigned long),
773 .proc_handler = &proc_doulongvec_minmax,
774 .strategy = &sysctl_intvec,
779 .ctl_name = KERN_COMPAT_LOG,
780 .procname = "compat-log",
782 .maxlen = sizeof (int),
784 .proc_handler = &proc_dointvec,
787 #ifdef CONFIG_RT_MUTEXES
789 .ctl_name = KERN_MAX_LOCK_DEPTH,
790 .procname = "max_lock_depth",
791 .data = &max_lock_depth,
792 .maxlen = sizeof(int),
794 .proc_handler = &proc_dointvec,
797 #ifdef CONFIG_PROC_FS
799 .ctl_name = CTL_UNNUMBERED,
800 .procname = "maps_protect",
801 .data = &maps_protect,
802 .maxlen = sizeof(int),
804 .proc_handler = &proc_dointvec,
808 .ctl_name = CTL_UNNUMBERED,
809 .procname = "poweroff_cmd",
810 .data = &poweroff_cmd,
811 .maxlen = POWEROFF_CMD_PATH_LEN,
813 .proc_handler = &proc_dostring,
814 .strategy = &sysctl_string,
818 .ctl_name = CTL_UNNUMBERED,
821 .child = key_sysctls,
825 * NOTE: do not add new entries to this table unless you have read
826 * Documentation/sysctl/ctl_unnumbered.txt
831 static struct ctl_table vm_table[] = {
833 .ctl_name = VM_OVERCOMMIT_MEMORY,
834 .procname = "overcommit_memory",
835 .data = &sysctl_overcommit_memory,
836 .maxlen = sizeof(sysctl_overcommit_memory),
838 .proc_handler = &proc_dointvec,
841 .ctl_name = VM_PANIC_ON_OOM,
842 .procname = "panic_on_oom",
843 .data = &sysctl_panic_on_oom,
844 .maxlen = sizeof(sysctl_panic_on_oom),
846 .proc_handler = &proc_dointvec,
849 .ctl_name = CTL_UNNUMBERED,
850 .procname = "oom_kill_allocating_task",
851 .data = &sysctl_oom_kill_allocating_task,
852 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
854 .proc_handler = &proc_dointvec,
857 .ctl_name = CTL_UNNUMBERED,
858 .procname = "oom_dump_tasks",
859 .data = &sysctl_oom_dump_tasks,
860 .maxlen = sizeof(sysctl_oom_dump_tasks),
862 .proc_handler = &proc_dointvec,
865 .ctl_name = VM_OVERCOMMIT_RATIO,
866 .procname = "overcommit_ratio",
867 .data = &sysctl_overcommit_ratio,
868 .maxlen = sizeof(sysctl_overcommit_ratio),
870 .proc_handler = &proc_dointvec,
873 .ctl_name = VM_PAGE_CLUSTER,
874 .procname = "page-cluster",
875 .data = &page_cluster,
876 .maxlen = sizeof(int),
878 .proc_handler = &proc_dointvec,
881 .ctl_name = VM_DIRTY_BACKGROUND,
882 .procname = "dirty_background_ratio",
883 .data = &dirty_background_ratio,
884 .maxlen = sizeof(dirty_background_ratio),
886 .proc_handler = &proc_dointvec_minmax,
887 .strategy = &sysctl_intvec,
889 .extra2 = &one_hundred,
892 .ctl_name = VM_DIRTY_RATIO,
893 .procname = "dirty_ratio",
894 .data = &vm_dirty_ratio,
895 .maxlen = sizeof(vm_dirty_ratio),
897 .proc_handler = &dirty_ratio_handler,
898 .strategy = &sysctl_intvec,
900 .extra2 = &one_hundred,
903 .procname = "dirty_writeback_centisecs",
904 .data = &dirty_writeback_interval,
905 .maxlen = sizeof(dirty_writeback_interval),
907 .proc_handler = &dirty_writeback_centisecs_handler,
910 .procname = "dirty_expire_centisecs",
911 .data = &dirty_expire_interval,
912 .maxlen = sizeof(dirty_expire_interval),
914 .proc_handler = &proc_dointvec_userhz_jiffies,
917 .ctl_name = VM_NR_PDFLUSH_THREADS,
918 .procname = "nr_pdflush_threads",
919 .data = &nr_pdflush_threads,
920 .maxlen = sizeof nr_pdflush_threads,
921 .mode = 0444 /* read-only*/,
922 .proc_handler = &proc_dointvec,
925 .ctl_name = VM_SWAPPINESS,
926 .procname = "swappiness",
927 .data = &vm_swappiness,
928 .maxlen = sizeof(vm_swappiness),
930 .proc_handler = &proc_dointvec_minmax,
931 .strategy = &sysctl_intvec,
933 .extra2 = &one_hundred,
935 #ifdef CONFIG_HUGETLB_PAGE
937 .procname = "nr_hugepages",
938 .data = &max_huge_pages,
939 .maxlen = sizeof(unsigned long),
941 .proc_handler = &hugetlb_sysctl_handler,
942 .extra1 = (void *)&hugetlb_zero,
943 .extra2 = (void *)&hugetlb_infinity,
946 .ctl_name = VM_HUGETLB_GROUP,
947 .procname = "hugetlb_shm_group",
948 .data = &sysctl_hugetlb_shm_group,
949 .maxlen = sizeof(gid_t),
951 .proc_handler = &proc_dointvec,
954 .ctl_name = CTL_UNNUMBERED,
955 .procname = "hugepages_treat_as_movable",
956 .data = &hugepages_treat_as_movable,
957 .maxlen = sizeof(int),
959 .proc_handler = &hugetlb_treat_movable_handler,
962 .ctl_name = CTL_UNNUMBERED,
963 .procname = "nr_overcommit_hugepages",
964 .data = &sysctl_overcommit_huge_pages,
965 .maxlen = sizeof(sysctl_overcommit_huge_pages),
967 .proc_handler = &hugetlb_overcommit_handler,
971 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
972 .procname = "lowmem_reserve_ratio",
973 .data = &sysctl_lowmem_reserve_ratio,
974 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
976 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
977 .strategy = &sysctl_intvec,
980 .ctl_name = VM_DROP_PAGECACHE,
981 .procname = "drop_caches",
982 .data = &sysctl_drop_caches,
983 .maxlen = sizeof(int),
985 .proc_handler = drop_caches_sysctl_handler,
986 .strategy = &sysctl_intvec,
989 .ctl_name = VM_MIN_FREE_KBYTES,
990 .procname = "min_free_kbytes",
991 .data = &min_free_kbytes,
992 .maxlen = sizeof(min_free_kbytes),
994 .proc_handler = &min_free_kbytes_sysctl_handler,
995 .strategy = &sysctl_intvec,
999 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
1000 .procname = "percpu_pagelist_fraction",
1001 .data = &percpu_pagelist_fraction,
1002 .maxlen = sizeof(percpu_pagelist_fraction),
1004 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
1005 .strategy = &sysctl_intvec,
1006 .extra1 = &min_percpu_pagelist_fract,
1010 .ctl_name = VM_MAX_MAP_COUNT,
1011 .procname = "max_map_count",
1012 .data = &sysctl_max_map_count,
1013 .maxlen = sizeof(sysctl_max_map_count),
1015 .proc_handler = &proc_dointvec
1019 .ctl_name = VM_LAPTOP_MODE,
1020 .procname = "laptop_mode",
1021 .data = &laptop_mode,
1022 .maxlen = sizeof(laptop_mode),
1024 .proc_handler = &proc_dointvec_jiffies,
1025 .strategy = &sysctl_jiffies,
1028 .ctl_name = VM_BLOCK_DUMP,
1029 .procname = "block_dump",
1030 .data = &block_dump,
1031 .maxlen = sizeof(block_dump),
1033 .proc_handler = &proc_dointvec,
1034 .strategy = &sysctl_intvec,
1038 .ctl_name = VM_VFS_CACHE_PRESSURE,
1039 .procname = "vfs_cache_pressure",
1040 .data = &sysctl_vfs_cache_pressure,
1041 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1043 .proc_handler = &proc_dointvec,
1044 .strategy = &sysctl_intvec,
1047 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1049 .ctl_name = VM_LEGACY_VA_LAYOUT,
1050 .procname = "legacy_va_layout",
1051 .data = &sysctl_legacy_va_layout,
1052 .maxlen = sizeof(sysctl_legacy_va_layout),
1054 .proc_handler = &proc_dointvec,
1055 .strategy = &sysctl_intvec,
1061 .ctl_name = VM_ZONE_RECLAIM_MODE,
1062 .procname = "zone_reclaim_mode",
1063 .data = &zone_reclaim_mode,
1064 .maxlen = sizeof(zone_reclaim_mode),
1066 .proc_handler = &proc_dointvec,
1067 .strategy = &sysctl_intvec,
1071 .ctl_name = VM_MIN_UNMAPPED,
1072 .procname = "min_unmapped_ratio",
1073 .data = &sysctl_min_unmapped_ratio,
1074 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1076 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
1077 .strategy = &sysctl_intvec,
1079 .extra2 = &one_hundred,
1082 .ctl_name = VM_MIN_SLAB,
1083 .procname = "min_slab_ratio",
1084 .data = &sysctl_min_slab_ratio,
1085 .maxlen = sizeof(sysctl_min_slab_ratio),
1087 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler,
1088 .strategy = &sysctl_intvec,
1090 .extra2 = &one_hundred,
1095 .ctl_name = CTL_UNNUMBERED,
1096 .procname = "stat_interval",
1097 .data = &sysctl_stat_interval,
1098 .maxlen = sizeof(sysctl_stat_interval),
1100 .proc_handler = &proc_dointvec_jiffies,
1101 .strategy = &sysctl_jiffies,
1104 #ifdef CONFIG_SECURITY
1106 .ctl_name = CTL_UNNUMBERED,
1107 .procname = "mmap_min_addr",
1108 .data = &mmap_min_addr,
1109 .maxlen = sizeof(unsigned long),
1111 .proc_handler = &proc_doulongvec_minmax,
1116 .ctl_name = CTL_UNNUMBERED,
1117 .procname = "numa_zonelist_order",
1118 .data = &numa_zonelist_order,
1119 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1121 .proc_handler = &numa_zonelist_order_handler,
1122 .strategy = &sysctl_string,
1125 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1126 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1128 .ctl_name = VM_VDSO_ENABLED,
1129 .procname = "vdso_enabled",
1130 .data = &vdso_enabled,
1131 .maxlen = sizeof(vdso_enabled),
1133 .proc_handler = &proc_dointvec,
1134 .strategy = &sysctl_intvec,
1138 #ifdef CONFIG_HIGHMEM
1140 .ctl_name = CTL_UNNUMBERED,
1141 .procname = "highmem_is_dirtyable",
1142 .data = &vm_highmem_is_dirtyable,
1143 .maxlen = sizeof(vm_highmem_is_dirtyable),
1145 .proc_handler = &proc_dointvec_minmax,
1146 .strategy = &sysctl_intvec,
1152 * NOTE: do not add new entries to this table unless you have read
1153 * Documentation/sysctl/ctl_unnumbered.txt
1158 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1159 static struct ctl_table binfmt_misc_table[] = {
1164 static struct ctl_table fs_table[] = {
1166 .ctl_name = FS_NRINODE,
1167 .procname = "inode-nr",
1168 .data = &inodes_stat,
1169 .maxlen = 2*sizeof(int),
1171 .proc_handler = &proc_dointvec,
1174 .ctl_name = FS_STATINODE,
1175 .procname = "inode-state",
1176 .data = &inodes_stat,
1177 .maxlen = 7*sizeof(int),
1179 .proc_handler = &proc_dointvec,
1182 .procname = "file-nr",
1183 .data = &files_stat,
1184 .maxlen = 3*sizeof(int),
1186 .proc_handler = &proc_nr_files,
1189 .ctl_name = FS_MAXFILE,
1190 .procname = "file-max",
1191 .data = &files_stat.max_files,
1192 .maxlen = sizeof(int),
1194 .proc_handler = &proc_dointvec,
1197 .ctl_name = CTL_UNNUMBERED,
1198 .procname = "nr_open",
1199 .data = &sysctl_nr_open,
1200 .maxlen = sizeof(int),
1202 .proc_handler = &proc_dointvec_minmax,
1203 .extra1 = &sysctl_nr_open_min,
1204 .extra2 = &sysctl_nr_open_max,
1207 .ctl_name = FS_DENTRY,
1208 .procname = "dentry-state",
1209 .data = &dentry_stat,
1210 .maxlen = 6*sizeof(int),
1212 .proc_handler = &proc_dointvec,
1215 .ctl_name = FS_OVERFLOWUID,
1216 .procname = "overflowuid",
1217 .data = &fs_overflowuid,
1218 .maxlen = sizeof(int),
1220 .proc_handler = &proc_dointvec_minmax,
1221 .strategy = &sysctl_intvec,
1222 .extra1 = &minolduid,
1223 .extra2 = &maxolduid,
1226 .ctl_name = FS_OVERFLOWGID,
1227 .procname = "overflowgid",
1228 .data = &fs_overflowgid,
1229 .maxlen = sizeof(int),
1231 .proc_handler = &proc_dointvec_minmax,
1232 .strategy = &sysctl_intvec,
1233 .extra1 = &minolduid,
1234 .extra2 = &maxolduid,
1237 .ctl_name = FS_LEASES,
1238 .procname = "leases-enable",
1239 .data = &leases_enable,
1240 .maxlen = sizeof(int),
1242 .proc_handler = &proc_dointvec,
1244 #ifdef CONFIG_DNOTIFY
1246 .ctl_name = FS_DIR_NOTIFY,
1247 .procname = "dir-notify-enable",
1248 .data = &dir_notify_enable,
1249 .maxlen = sizeof(int),
1251 .proc_handler = &proc_dointvec,
1256 .ctl_name = FS_LEASE_TIME,
1257 .procname = "lease-break-time",
1258 .data = &lease_break_time,
1259 .maxlen = sizeof(int),
1261 .proc_handler = &proc_dointvec_minmax,
1262 .strategy = &sysctl_intvec,
1267 .procname = "aio-nr",
1269 .maxlen = sizeof(aio_nr),
1271 .proc_handler = &proc_doulongvec_minmax,
1274 .procname = "aio-max-nr",
1275 .data = &aio_max_nr,
1276 .maxlen = sizeof(aio_max_nr),
1278 .proc_handler = &proc_doulongvec_minmax,
1280 #ifdef CONFIG_INOTIFY_USER
1282 .ctl_name = FS_INOTIFY,
1283 .procname = "inotify",
1285 .child = inotify_table,
1290 .ctl_name = KERN_SETUID_DUMPABLE,
1291 .procname = "suid_dumpable",
1292 .data = &suid_dumpable,
1293 .maxlen = sizeof(int),
1295 .proc_handler = &proc_dointvec,
1297 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1299 .ctl_name = CTL_UNNUMBERED,
1300 .procname = "binfmt_misc",
1302 .child = binfmt_misc_table,
1306 * NOTE: do not add new entries to this table unless you have read
1307 * Documentation/sysctl/ctl_unnumbered.txt
1312 static struct ctl_table debug_table[] = {
1313 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1315 .ctl_name = CTL_UNNUMBERED,
1316 .procname = "exception-trace",
1317 .data = &show_unhandled_signals,
1318 .maxlen = sizeof(int),
1320 .proc_handler = proc_dointvec
1326 static struct ctl_table dev_table[] = {
1330 static DEFINE_SPINLOCK(sysctl_lock);
1332 /* called under sysctl_lock */
1333 static int use_table(struct ctl_table_header *p)
1335 if (unlikely(p->unregistering))
1341 /* called under sysctl_lock */
1342 static void unuse_table(struct ctl_table_header *p)
1345 if (unlikely(p->unregistering))
1346 complete(p->unregistering);
1349 /* called under sysctl_lock, will reacquire if has to wait */
1350 static void start_unregistering(struct ctl_table_header *p)
1353 * if p->used is 0, nobody will ever touch that entry again;
1354 * we'll eliminate all paths to it before dropping sysctl_lock
1356 if (unlikely(p->used)) {
1357 struct completion wait;
1358 init_completion(&wait);
1359 p->unregistering = &wait;
1360 spin_unlock(&sysctl_lock);
1361 wait_for_completion(&wait);
1362 spin_lock(&sysctl_lock);
1365 * do not remove from the list until nobody holds it; walking the
1366 * list in do_sysctl() relies on that.
1368 list_del_init(&p->ctl_entry);
1371 void sysctl_head_finish(struct ctl_table_header *head)
1375 spin_lock(&sysctl_lock);
1377 spin_unlock(&sysctl_lock);
1380 static struct list_head *
1381 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1383 struct list_head *header_list;
1384 header_list = &root->header_list;
1386 header_list = root->lookup(root, namespaces);
1390 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1391 struct ctl_table_header *prev)
1393 struct ctl_table_root *root;
1394 struct list_head *header_list;
1395 struct ctl_table_header *head;
1396 struct list_head *tmp;
1398 spin_lock(&sysctl_lock);
1401 tmp = &prev->ctl_entry;
1405 tmp = &root_table_header.ctl_entry;
1407 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1409 if (!use_table(head))
1411 spin_unlock(&sysctl_lock);
1416 header_list = lookup_header_list(root, namespaces);
1417 if (tmp != header_list)
1421 root = list_entry(root->root_list.next,
1422 struct ctl_table_root, root_list);
1423 if (root == &sysctl_table_root)
1425 header_list = lookup_header_list(root, namespaces);
1426 } while (list_empty(header_list));
1427 tmp = header_list->next;
1430 spin_unlock(&sysctl_lock);
1434 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1436 return __sysctl_head_next(current->nsproxy, prev);
1439 void register_sysctl_root(struct ctl_table_root *root)
1441 spin_lock(&sysctl_lock);
1442 list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1443 spin_unlock(&sysctl_lock);
1446 #ifdef CONFIG_SYSCTL_SYSCALL
1447 /* Perform the actual read/write of a sysctl table entry. */
1448 static int do_sysctl_strategy(struct ctl_table_root *root,
1449 struct ctl_table *table,
1450 int __user *name, int nlen,
1451 void __user *oldval, size_t __user *oldlenp,
1452 void __user *newval, size_t newlen)
1460 if (sysctl_perm(root, table, op))
1463 if (table->strategy) {
1464 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1472 /* If there is no strategy routine, or if the strategy returns
1473 * zero, proceed with automatic r/w */
1474 if (table->data && table->maxlen) {
1475 rc = sysctl_data(table, name, nlen, oldval, oldlenp,
1483 static int parse_table(int __user *name, int nlen,
1484 void __user *oldval, size_t __user *oldlenp,
1485 void __user *newval, size_t newlen,
1486 struct ctl_table_root *root,
1487 struct ctl_table *table)
1493 if (get_user(n, name))
1495 for ( ; table->ctl_name || table->procname; table++) {
1496 if (!table->ctl_name)
1498 if (n == table->ctl_name) {
1501 if (sysctl_perm(root, table, 001))
1505 table = table->child;
1508 error = do_sysctl_strategy(root, table, name, nlen,
1517 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1518 void __user *newval, size_t newlen)
1520 struct ctl_table_header *head;
1521 int error = -ENOTDIR;
1523 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1527 if (!oldlenp || get_user(old_len, oldlenp))
1531 for (head = sysctl_head_next(NULL); head;
1532 head = sysctl_head_next(head)) {
1533 error = parse_table(name, nlen, oldval, oldlenp,
1535 head->root, head->ctl_table);
1536 if (error != -ENOTDIR) {
1537 sysctl_head_finish(head);
1544 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1546 struct __sysctl_args tmp;
1549 if (copy_from_user(&tmp, args, sizeof(tmp)))
1552 error = deprecated_sysctl_warning(&tmp);
1557 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1558 tmp.newval, tmp.newlen);
1563 #endif /* CONFIG_SYSCTL_SYSCALL */
1566 * sysctl_perm does NOT grant the superuser all rights automatically, because
1567 * some sysctl variables are readonly even to root.
1570 static int test_perm(int mode, int op)
1574 else if (in_egroup_p(0))
1576 if ((mode & op & 0007) == op)
1581 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1586 error = security_sysctl(table, op);
1590 if (root->permissions)
1591 mode = root->permissions(root, current->nsproxy, table);
1595 return test_perm(mode, op);
1598 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1600 for (; table->ctl_name || table->procname; table++) {
1601 table->parent = parent;
1603 sysctl_set_parent(table, table->child);
1607 static __init int sysctl_init(void)
1609 sysctl_set_parent(NULL, root_table);
1610 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1613 err = sysctl_check_table(current->nsproxy, root_table);
1619 core_initcall(sysctl_init);
1622 * __register_sysctl_paths - register a sysctl hierarchy
1623 * @root: List of sysctl headers to register on
1624 * @namespaces: Data to compute which lists of sysctl entries are visible
1625 * @path: The path to the directory the sysctl table is in.
1626 * @table: the top-level table structure
1628 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1629 * array. A completely 0 filled entry terminates the table.
1631 * The members of the &struct ctl_table structure are used as follows:
1633 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1634 * must be unique within that level of sysctl
1636 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1637 * enter a sysctl file
1639 * data - a pointer to data for use by proc_handler
1641 * maxlen - the maximum size in bytes of the data
1643 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1645 * child - a pointer to the child sysctl table if this entry is a directory, or
1648 * proc_handler - the text handler routine (described below)
1650 * strategy - the strategy routine (described below)
1652 * de - for internal use by the sysctl routines
1654 * extra1, extra2 - extra pointers usable by the proc handler routines
1656 * Leaf nodes in the sysctl tree will be represented by a single file
1657 * under /proc; non-leaf nodes will be represented by directories.
1659 * sysctl(2) can automatically manage read and write requests through
1660 * the sysctl table. The data and maxlen fields of the ctl_table
1661 * struct enable minimal validation of the values being written to be
1662 * performed, and the mode field allows minimal authentication.
1664 * More sophisticated management can be enabled by the provision of a
1665 * strategy routine with the table entry. This will be called before
1666 * any automatic read or write of the data is performed.
1668 * The strategy routine may return
1670 * < 0 - Error occurred (error is passed to user process)
1672 * 0 - OK - proceed with automatic read or write.
1674 * > 0 - OK - read or write has been done by the strategy routine, so
1675 * return immediately.
1677 * There must be a proc_handler routine for any terminal nodes
1678 * mirrored under /proc/sys (non-terminals are handled by a built-in
1679 * directory handler). Several default handlers are available to
1680 * cover common cases -
1682 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1683 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1684 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1686 * It is the handler's job to read the input buffer from user memory
1687 * and process it. The handler should return 0 on success.
1689 * This routine returns %NULL on a failure to register, and a pointer
1690 * to the table header on success.
1692 struct ctl_table_header *__register_sysctl_paths(
1693 struct ctl_table_root *root,
1694 struct nsproxy *namespaces,
1695 const struct ctl_path *path, struct ctl_table *table)
1697 struct list_head *header_list;
1698 struct ctl_table_header *header;
1699 struct ctl_table *new, **prevp;
1700 unsigned int n, npath;
1702 /* Count the path components */
1703 for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
1707 * For each path component, allocate a 2-element ctl_table array.
1708 * The first array element will be filled with the sysctl entry
1709 * for this, the second will be the sentinel (ctl_name == 0).
1711 * We allocate everything in one go so that we don't have to
1712 * worry about freeing additional memory in unregister_sysctl_table.
1714 header = kzalloc(sizeof(struct ctl_table_header) +
1715 (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
1719 new = (struct ctl_table *) (header + 1);
1721 /* Now connect the dots */
1722 prevp = &header->ctl_table;
1723 for (n = 0; n < npath; ++n, ++path) {
1724 /* Copy the procname */
1725 new->procname = path->procname;
1726 new->ctl_name = path->ctl_name;
1730 prevp = &new->child;
1735 header->ctl_table_arg = table;
1737 INIT_LIST_HEAD(&header->ctl_entry);
1739 header->unregistering = NULL;
1740 header->root = root;
1741 sysctl_set_parent(NULL, header->ctl_table);
1742 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1743 if (sysctl_check_table(namespaces, header->ctl_table)) {
1748 spin_lock(&sysctl_lock);
1749 header_list = lookup_header_list(root, namespaces);
1750 list_add_tail(&header->ctl_entry, header_list);
1751 spin_unlock(&sysctl_lock);
1757 * register_sysctl_table_path - register a sysctl table hierarchy
1758 * @path: The path to the directory the sysctl table is in.
1759 * @table: the top-level table structure
1761 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1762 * array. A completely 0 filled entry terminates the table.
1764 * See __register_sysctl_paths for more details.
1766 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1767 struct ctl_table *table)
1769 return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
1774 * register_sysctl_table - register a sysctl table hierarchy
1775 * @table: the top-level table structure
1777 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1778 * array. A completely 0 filled entry terminates the table.
1780 * See register_sysctl_paths for more details.
1782 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
1784 static const struct ctl_path null_path[] = { {} };
1786 return register_sysctl_paths(null_path, table);
1790 * unregister_sysctl_table - unregister a sysctl table hierarchy
1791 * @header: the header returned from register_sysctl_table
1793 * Unregisters the sysctl table and all children. proc entries may not
1794 * actually be removed until they are no longer used by anyone.
1796 void unregister_sysctl_table(struct ctl_table_header * header)
1803 spin_lock(&sysctl_lock);
1804 start_unregistering(header);
1805 spin_unlock(&sysctl_lock);
1809 #else /* !CONFIG_SYSCTL */
1810 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
1815 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1816 struct ctl_table *table)
1821 void unregister_sysctl_table(struct ctl_table_header * table)
1825 #endif /* CONFIG_SYSCTL */
1831 #ifdef CONFIG_PROC_SYSCTL
1833 static int _proc_do_string(void* data, int maxlen, int write,
1834 struct file *filp, void __user *buffer,
1835 size_t *lenp, loff_t *ppos)
1841 if (!data || !maxlen || !*lenp) {
1849 while (len < *lenp) {
1850 if (get_user(c, p++))
1852 if (c == 0 || c == '\n')
1858 if(copy_from_user(data, buffer, len))
1860 ((char *) data)[len] = 0;
1878 if(copy_to_user(buffer, data, len))
1881 if(put_user('\n', ((char __user *) buffer) + len))
1892 * proc_dostring - read a string sysctl
1893 * @table: the sysctl table
1894 * @write: %TRUE if this is a write to the sysctl file
1895 * @filp: the file structure
1896 * @buffer: the user buffer
1897 * @lenp: the size of the user buffer
1898 * @ppos: file position
1900 * Reads/writes a string from/to the user buffer. If the kernel
1901 * buffer provided is not large enough to hold the string, the
1902 * string is truncated. The copied string is %NULL-terminated.
1903 * If the string is being read by the user process, it is copied
1904 * and a newline '\n' is added. It is truncated if the buffer is
1907 * Returns 0 on success.
1909 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
1910 void __user *buffer, size_t *lenp, loff_t *ppos)
1912 return _proc_do_string(table->data, table->maxlen, write, filp,
1913 buffer, lenp, ppos);
1917 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1919 int write, void *data)
1922 *valp = *negp ? -*lvalp : *lvalp;
1927 *lvalp = (unsigned long)-val;
1930 *lvalp = (unsigned long)val;
1936 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
1937 int write, struct file *filp, void __user *buffer,
1938 size_t *lenp, loff_t *ppos,
1939 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1940 int write, void *data),
1943 #define TMPBUFLEN 21
1944 int *i, vleft, first=1, neg, val;
1948 char buf[TMPBUFLEN], *p;
1949 char __user *s = buffer;
1951 if (!tbl_data || !table->maxlen || !*lenp ||
1952 (*ppos && !write)) {
1957 i = (int *) tbl_data;
1958 vleft = table->maxlen / sizeof(*i);
1962 conv = do_proc_dointvec_conv;
1964 for (; left && vleft--; i++, first=0) {
1979 if (len > sizeof(buf) - 1)
1980 len = sizeof(buf) - 1;
1981 if (copy_from_user(buf, s, len))
1985 if (*p == '-' && left > 1) {
1989 if (*p < '0' || *p > '9')
1992 lval = simple_strtoul(p, &p, 0);
1995 if ((len < left) && *p && !isspace(*p))
2002 if (conv(&neg, &lval, i, 1, data))
2009 if (conv(&neg, &lval, i, 0, data))
2012 sprintf(p, "%s%lu", neg ? "-" : "", lval);
2016 if(copy_to_user(s, buf, len))
2023 if (!write && !first && left) {
2024 if(put_user('\n', s))
2031 if (get_user(c, s++))
2046 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2047 void __user *buffer, size_t *lenp, loff_t *ppos,
2048 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2049 int write, void *data),
2052 return __do_proc_dointvec(table->data, table, write, filp,
2053 buffer, lenp, ppos, conv, data);
2057 * proc_dointvec - read a vector of integers
2058 * @table: the sysctl table
2059 * @write: %TRUE if this is a write to the sysctl file
2060 * @filp: the file structure
2061 * @buffer: the user buffer
2062 * @lenp: the size of the user buffer
2063 * @ppos: file position
2065 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2066 * values from/to the user buffer, treated as an ASCII string.
2068 * Returns 0 on success.
2070 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2071 void __user *buffer, size_t *lenp, loff_t *ppos)
2073 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2081 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
2083 int write, void *data)
2085 int op = *(int *)data;
2087 int val = *negp ? -*lvalp : *lvalp;
2089 case OP_SET: *valp = val; break;
2090 case OP_AND: *valp &= val; break;
2091 case OP_OR: *valp |= val; break;
2097 *lvalp = (unsigned long)-val;
2100 *lvalp = (unsigned long)val;
2107 * Taint values can only be increased
2109 static int proc_dointvec_taint(struct ctl_table *table, int write, struct file *filp,
2110 void __user *buffer, size_t *lenp, loff_t *ppos)
2114 if (write && !capable(CAP_SYS_ADMIN))
2118 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2119 do_proc_dointvec_bset_conv,&op);
2122 struct do_proc_dointvec_minmax_conv_param {
2127 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2129 int write, void *data)
2131 struct do_proc_dointvec_minmax_conv_param *param = data;
2133 int val = *negp ? -*lvalp : *lvalp;
2134 if ((param->min && *param->min > val) ||
2135 (param->max && *param->max < val))
2142 *lvalp = (unsigned long)-val;
2145 *lvalp = (unsigned long)val;
2152 * proc_dointvec_minmax - read a vector of integers with min/max values
2153 * @table: the sysctl table
2154 * @write: %TRUE if this is a write to the sysctl file
2155 * @filp: the file structure
2156 * @buffer: the user buffer
2157 * @lenp: the size of the user buffer
2158 * @ppos: file position
2160 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2161 * values from/to the user buffer, treated as an ASCII string.
2163 * This routine will ensure the values are within the range specified by
2164 * table->extra1 (min) and table->extra2 (max).
2166 * Returns 0 on success.
2168 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2169 void __user *buffer, size_t *lenp, loff_t *ppos)
2171 struct do_proc_dointvec_minmax_conv_param param = {
2172 .min = (int *) table->extra1,
2173 .max = (int *) table->extra2,
2175 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2176 do_proc_dointvec_minmax_conv, ¶m);
2179 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2181 void __user *buffer,
2182 size_t *lenp, loff_t *ppos,
2183 unsigned long convmul,
2184 unsigned long convdiv)
2186 #define TMPBUFLEN 21
2187 unsigned long *i, *min, *max, val;
2188 int vleft, first=1, neg;
2190 char buf[TMPBUFLEN], *p;
2191 char __user *s = buffer;
2193 if (!data || !table->maxlen || !*lenp ||
2194 (*ppos && !write)) {
2199 i = (unsigned long *) data;
2200 min = (unsigned long *) table->extra1;
2201 max = (unsigned long *) table->extra2;
2202 vleft = table->maxlen / sizeof(unsigned long);
2205 for (; left && vleft--; i++, min++, max++, first=0) {
2220 if (len > TMPBUFLEN-1)
2222 if (copy_from_user(buf, s, len))
2226 if (*p == '-' && left > 1) {
2230 if (*p < '0' || *p > '9')
2232 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2234 if ((len < left) && *p && !isspace(*p))
2243 if ((min && val < *min) || (max && val > *max))
2250 sprintf(p, "%lu", convdiv * (*i) / convmul);
2254 if(copy_to_user(s, buf, len))
2261 if (!write && !first && left) {
2262 if(put_user('\n', s))
2269 if (get_user(c, s++))
2284 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2286 void __user *buffer,
2287 size_t *lenp, loff_t *ppos,
2288 unsigned long convmul,
2289 unsigned long convdiv)
2291 return __do_proc_doulongvec_minmax(table->data, table, write,
2292 filp, buffer, lenp, ppos, convmul, convdiv);
2296 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2297 * @table: the sysctl table
2298 * @write: %TRUE if this is a write to the sysctl file
2299 * @filp: the file structure
2300 * @buffer: the user buffer
2301 * @lenp: the size of the user buffer
2302 * @ppos: file position
2304 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2305 * values from/to the user buffer, treated as an ASCII string.
2307 * This routine will ensure the values are within the range specified by
2308 * table->extra1 (min) and table->extra2 (max).
2310 * Returns 0 on success.
2312 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2313 void __user *buffer, size_t *lenp, loff_t *ppos)
2315 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2319 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2320 * @table: the sysctl table
2321 * @write: %TRUE if this is a write to the sysctl file
2322 * @filp: the file structure
2323 * @buffer: the user buffer
2324 * @lenp: the size of the user buffer
2325 * @ppos: file position
2327 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2328 * values from/to the user buffer, treated as an ASCII string. The values
2329 * are treated as milliseconds, and converted to jiffies when they are stored.
2331 * This routine will ensure the values are within the range specified by
2332 * table->extra1 (min) and table->extra2 (max).
2334 * Returns 0 on success.
2336 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2338 void __user *buffer,
2339 size_t *lenp, loff_t *ppos)
2341 return do_proc_doulongvec_minmax(table, write, filp, buffer,
2342 lenp, ppos, HZ, 1000l);
2346 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2348 int write, void *data)
2351 if (*lvalp > LONG_MAX / HZ)
2353 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2359 lval = (unsigned long)-val;
2362 lval = (unsigned long)val;
2369 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2371 int write, void *data)
2374 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2376 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2382 lval = (unsigned long)-val;
2385 lval = (unsigned long)val;
2387 *lvalp = jiffies_to_clock_t(lval);
2392 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2394 int write, void *data)
2397 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2403 lval = (unsigned long)-val;
2406 lval = (unsigned long)val;
2408 *lvalp = jiffies_to_msecs(lval);
2414 * proc_dointvec_jiffies - read a vector of integers as seconds
2415 * @table: the sysctl table
2416 * @write: %TRUE if this is a write to the sysctl file
2417 * @filp: the file structure
2418 * @buffer: the user buffer
2419 * @lenp: the size of the user buffer
2420 * @ppos: file position
2422 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2423 * values from/to the user buffer, treated as an ASCII string.
2424 * The values read are assumed to be in seconds, and are converted into
2427 * Returns 0 on success.
2429 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2430 void __user *buffer, size_t *lenp, loff_t *ppos)
2432 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2433 do_proc_dointvec_jiffies_conv,NULL);
2437 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2438 * @table: the sysctl table
2439 * @write: %TRUE if this is a write to the sysctl file
2440 * @filp: the file structure
2441 * @buffer: the user buffer
2442 * @lenp: the size of the user buffer
2443 * @ppos: pointer to the file position
2445 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2446 * values from/to the user buffer, treated as an ASCII string.
2447 * The values read are assumed to be in 1/USER_HZ seconds, and
2448 * are converted into jiffies.
2450 * Returns 0 on success.
2452 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2453 void __user *buffer, size_t *lenp, loff_t *ppos)
2455 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2456 do_proc_dointvec_userhz_jiffies_conv,NULL);
2460 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2461 * @table: the sysctl table
2462 * @write: %TRUE if this is a write to the sysctl file
2463 * @filp: the file structure
2464 * @buffer: the user buffer
2465 * @lenp: the size of the user buffer
2466 * @ppos: file position
2467 * @ppos: the current position in the file
2469 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2470 * values from/to the user buffer, treated as an ASCII string.
2471 * The values read are assumed to be in 1/1000 seconds, and
2472 * are converted into jiffies.
2474 * Returns 0 on success.
2476 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2477 void __user *buffer, size_t *lenp, loff_t *ppos)
2479 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2480 do_proc_dointvec_ms_jiffies_conv, NULL);
2483 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2484 void __user *buffer, size_t *lenp, loff_t *ppos)
2486 struct pid *new_pid;
2490 tmp = pid_vnr(cad_pid);
2492 r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2493 lenp, ppos, NULL, NULL);
2497 new_pid = find_get_pid(tmp);
2501 put_pid(xchg(&cad_pid, new_pid));
2505 #else /* CONFIG_PROC_FS */
2507 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2508 void __user *buffer, size_t *lenp, loff_t *ppos)
2513 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2514 void __user *buffer, size_t *lenp, loff_t *ppos)
2519 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2520 void __user *buffer, size_t *lenp, loff_t *ppos)
2525 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2526 void __user *buffer, size_t *lenp, loff_t *ppos)
2531 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2532 void __user *buffer, size_t *lenp, loff_t *ppos)
2537 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2538 void __user *buffer, size_t *lenp, loff_t *ppos)
2543 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2544 void __user *buffer, size_t *lenp, loff_t *ppos)
2549 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2551 void __user *buffer,
2552 size_t *lenp, loff_t *ppos)
2558 #endif /* CONFIG_PROC_FS */
2561 #ifdef CONFIG_SYSCTL_SYSCALL
2563 * General sysctl support routines
2566 /* The generic sysctl data routine (used if no strategy routine supplied) */
2567 int sysctl_data(struct ctl_table *table, int __user *name, int nlen,
2568 void __user *oldval, size_t __user *oldlenp,
2569 void __user *newval, size_t newlen)
2573 /* Get out of I don't have a variable */
2574 if (!table->data || !table->maxlen)
2577 if (oldval && oldlenp) {
2578 if (get_user(len, oldlenp))
2581 if (len > table->maxlen)
2582 len = table->maxlen;
2583 if (copy_to_user(oldval, table->data, len))
2585 if (put_user(len, oldlenp))
2590 if (newval && newlen) {
2591 if (newlen > table->maxlen)
2592 newlen = table->maxlen;
2594 if (copy_from_user(table->data, newval, newlen))
2600 /* The generic string strategy routine: */
2601 int sysctl_string(struct ctl_table *table, int __user *name, int nlen,
2602 void __user *oldval, size_t __user *oldlenp,
2603 void __user *newval, size_t newlen)
2605 if (!table->data || !table->maxlen)
2608 if (oldval && oldlenp) {
2610 if (get_user(bufsize, oldlenp))
2613 size_t len = strlen(table->data), copied;
2615 /* This shouldn't trigger for a well-formed sysctl */
2616 if (len > table->maxlen)
2617 len = table->maxlen;
2619 /* Copy up to a max of bufsize-1 bytes of the string */
2620 copied = (len >= bufsize) ? bufsize - 1 : len;
2622 if (copy_to_user(oldval, table->data, copied) ||
2623 put_user(0, (char __user *)(oldval + copied)))
2625 if (put_user(len, oldlenp))
2629 if (newval && newlen) {
2630 size_t len = newlen;
2631 if (len > table->maxlen)
2632 len = table->maxlen;
2633 if(copy_from_user(table->data, newval, len))
2635 if (len == table->maxlen)
2637 ((char *) table->data)[len] = 0;
2643 * This function makes sure that all of the integers in the vector
2644 * are between the minimum and maximum values given in the arrays
2645 * table->extra1 and table->extra2, respectively.
2647 int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen,
2648 void __user *oldval, size_t __user *oldlenp,
2649 void __user *newval, size_t newlen)
2652 if (newval && newlen) {
2653 int __user *vec = (int __user *) newval;
2654 int *min = (int *) table->extra1;
2655 int *max = (int *) table->extra2;
2659 if (newlen % sizeof(int) != 0)
2662 if (!table->extra1 && !table->extra2)
2665 if (newlen > table->maxlen)
2666 newlen = table->maxlen;
2667 length = newlen / sizeof(int);
2669 for (i = 0; i < length; i++) {
2671 if (get_user(value, vec + i))
2673 if (min && value < min[i])
2675 if (max && value > max[i])
2682 /* Strategy function to convert jiffies to seconds */
2683 int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen,
2684 void __user *oldval, size_t __user *oldlenp,
2685 void __user *newval, size_t newlen)
2687 if (oldval && oldlenp) {
2690 if (get_user(olen, oldlenp))
2695 if (olen < sizeof(int))
2698 val = *(int *)(table->data) / HZ;
2699 if (put_user(val, (int __user *)oldval))
2701 if (put_user(sizeof(int), oldlenp))
2705 if (newval && newlen) {
2707 if (newlen != sizeof(int))
2709 if (get_user(new, (int __user *)newval))
2711 *(int *)(table->data) = new*HZ;
2716 /* Strategy function to convert jiffies to seconds */
2717 int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen,
2718 void __user *oldval, size_t __user *oldlenp,
2719 void __user *newval, size_t newlen)
2721 if (oldval && oldlenp) {
2724 if (get_user(olen, oldlenp))
2729 if (olen < sizeof(int))
2732 val = jiffies_to_msecs(*(int *)(table->data));
2733 if (put_user(val, (int __user *)oldval))
2735 if (put_user(sizeof(int), oldlenp))
2739 if (newval && newlen) {
2741 if (newlen != sizeof(int))
2743 if (get_user(new, (int __user *)newval))
2745 *(int *)(table->data) = msecs_to_jiffies(new);
2752 #else /* CONFIG_SYSCTL_SYSCALL */
2755 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2757 struct __sysctl_args tmp;
2760 if (copy_from_user(&tmp, args, sizeof(tmp)))
2763 error = deprecated_sysctl_warning(&tmp);
2765 /* If no error reading the parameters then just -ENOSYS ... */
2772 int sysctl_data(struct ctl_table *table, int __user *name, int nlen,
2773 void __user *oldval, size_t __user *oldlenp,
2774 void __user *newval, size_t newlen)
2779 int sysctl_string(struct ctl_table *table, int __user *name, int nlen,
2780 void __user *oldval, size_t __user *oldlenp,
2781 void __user *newval, size_t newlen)
2786 int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen,
2787 void __user *oldval, size_t __user *oldlenp,
2788 void __user *newval, size_t newlen)
2793 int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen,
2794 void __user *oldval, size_t __user *oldlenp,
2795 void __user *newval, size_t newlen)
2800 int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen,
2801 void __user *oldval, size_t __user *oldlenp,
2802 void __user *newval, size_t newlen)
2807 #endif /* CONFIG_SYSCTL_SYSCALL */
2809 static int deprecated_sysctl_warning(struct __sysctl_args *args)
2811 static int msg_count;
2812 int name[CTL_MAXNAME];
2815 /* Check args->nlen. */
2816 if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
2819 /* Read in the sysctl name for better debug message logging */
2820 for (i = 0; i < args->nlen; i++)
2821 if (get_user(name[i], args->name + i))
2824 /* Ignore accesses to kernel.version */
2825 if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
2828 if (msg_count < 5) {
2831 "warning: process `%s' used the deprecated sysctl "
2832 "system call with ", current->comm);
2833 for (i = 0; i < args->nlen; i++)
2834 printk("%d.", name[i]);
2841 * No sense putting this after each symbol definition, twice,
2842 * exception granted :-)
2844 EXPORT_SYMBOL(proc_dointvec);
2845 EXPORT_SYMBOL(proc_dointvec_jiffies);
2846 EXPORT_SYMBOL(proc_dointvec_minmax);
2847 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2848 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2849 EXPORT_SYMBOL(proc_dostring);
2850 EXPORT_SYMBOL(proc_doulongvec_minmax);
2851 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2852 EXPORT_SYMBOL(register_sysctl_table);
2853 EXPORT_SYMBOL(register_sysctl_paths);
2854 EXPORT_SYMBOL(sysctl_intvec);
2855 EXPORT_SYMBOL(sysctl_jiffies);
2856 EXPORT_SYMBOL(sysctl_ms_jiffies);
2857 EXPORT_SYMBOL(sysctl_string);
2858 EXPORT_SYMBOL(sysctl_data);
2859 EXPORT_SYMBOL(unregister_sysctl_table);