V4L/DVB: v4l2-ctrls: reorder 'case' statements to match order in header
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / kernel / sysctl.c
blob6d850bf0a5178f3b6c5c435e89f6d6f2dfb8cfa5
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/signal.h>
27 #include <linux/proc_fs.h>
28 #include <linux/security.h>
29 #include <linux/ctype.h>
30 #include <linux/kmemcheck.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/ratelimit.h>
40 #include <linux/compaction.h>
41 #include <linux/hugetlb.h>
42 #include <linux/initrd.h>
43 #include <linux/key.h>
44 #include <linux/times.h>
45 #include <linux/limits.h>
46 #include <linux/dcache.h>
47 #include <linux/syscalls.h>
48 #include <linux/vmstat.h>
49 #include <linux/nfs_fs.h>
50 #include <linux/acpi.h>
51 #include <linux/reboot.h>
52 #include <linux/ftrace.h>
53 #include <linux/perf_event.h>
54 #include <linux/kprobes.h>
55 #include <linux/pipe_fs_i.h>
57 #include <asm/uaccess.h>
58 #include <asm/processor.h>
60 #ifdef CONFIG_X86
61 #include <asm/nmi.h>
62 #include <asm/stacktrace.h>
63 #include <asm/io.h>
64 #endif
65 #ifdef CONFIG_BSD_PROCESS_ACCT
66 #include <linux/acct.h>
67 #endif
68 #ifdef CONFIG_RT_MUTEXES
69 #include <linux/rtmutex.h>
70 #endif
71 #if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT)
72 #include <linux/lockdep.h>
73 #endif
74 #ifdef CONFIG_CHR_DEV_SG
75 #include <scsi/sg.h>
76 #endif
78 #ifdef CONFIG_LOCKUP_DETECTOR
79 #include <linux/nmi.h>
80 #endif
83 #if defined(CONFIG_SYSCTL)
85 /* External variables not in a header file. */
86 extern int sysctl_overcommit_memory;
87 extern int sysctl_overcommit_ratio;
88 extern int sysctl_panic_on_oom;
89 extern int sysctl_oom_kill_allocating_task;
90 extern int sysctl_oom_dump_tasks;
91 extern int max_threads;
92 extern int core_uses_pid;
93 extern int suid_dumpable;
94 extern char core_pattern[];
95 extern unsigned int core_pipe_limit;
96 extern int pid_max;
97 extern int min_free_kbytes;
98 extern int pid_max_min, pid_max_max;
99 extern int sysctl_drop_caches;
100 extern int percpu_pagelist_fraction;
101 extern int compat_log;
102 extern int latencytop_enabled;
103 extern int sysctl_nr_open_min, sysctl_nr_open_max;
104 #ifndef CONFIG_MMU
105 extern int sysctl_nr_trim_pages;
106 #endif
107 #ifdef CONFIG_BLOCK
108 extern int blk_iopoll_enabled;
109 #endif
111 /* Constants used for minimum and maximum */
112 #ifdef CONFIG_LOCKUP_DETECTOR
113 static int sixty = 60;
114 static int neg_one = -1;
115 #endif
117 static int zero;
118 static int __maybe_unused one = 1;
119 static int __maybe_unused two = 2;
120 static unsigned long one_ul = 1;
121 static int one_hundred = 100;
122 #ifdef CONFIG_PRINTK
123 static int ten_thousand = 10000;
124 #endif
126 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
127 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
129 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
130 static int maxolduid = 65535;
131 static int minolduid;
132 static int min_percpu_pagelist_fract = 8;
134 static int ngroups_max = NGROUPS_MAX;
136 #ifdef CONFIG_SPARC
137 #include <asm/system.h>
138 #endif
140 #ifdef CONFIG_SPARC64
141 extern int sysctl_tsb_ratio;
142 #endif
144 #ifdef __hppa__
145 extern int pwrsw_enabled;
146 extern int unaligned_enabled;
147 #endif
149 #ifdef CONFIG_S390
150 #ifdef CONFIG_MATHEMU
151 extern int sysctl_ieee_emulation_warnings;
152 #endif
153 extern int sysctl_userprocess_debug;
154 extern int spin_retry;
155 #endif
157 #ifdef CONFIG_IA64
158 extern int no_unaligned_warning;
159 extern int unaligned_dump_stack;
160 #endif
162 extern struct ratelimit_state printk_ratelimit_state;
164 #ifdef CONFIG_PROC_SYSCTL
165 static int proc_do_cad_pid(struct ctl_table *table, int write,
166 void __user *buffer, size_t *lenp, loff_t *ppos);
167 static int proc_taint(struct ctl_table *table, int write,
168 void __user *buffer, size_t *lenp, loff_t *ppos);
169 #endif
171 #ifdef CONFIG_MAGIC_SYSRQ
172 static int __sysrq_enabled; /* Note: sysrq code ises it's own private copy */
174 static int sysrq_sysctl_handler(ctl_table *table, int write,
175 void __user *buffer, size_t *lenp,
176 loff_t *ppos)
178 int error;
180 error = proc_dointvec(table, write, buffer, lenp, ppos);
181 if (error)
182 return error;
184 if (write)
185 sysrq_toggle_support(__sysrq_enabled);
187 return 0;
190 #endif
192 static struct ctl_table root_table[];
193 static struct ctl_table_root sysctl_table_root;
194 static struct ctl_table_header root_table_header = {
195 .count = 1,
196 .ctl_table = root_table,
197 .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
198 .root = &sysctl_table_root,
199 .set = &sysctl_table_root.default_set,
201 static struct ctl_table_root sysctl_table_root = {
202 .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
203 .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
206 static struct ctl_table kern_table[];
207 static struct ctl_table vm_table[];
208 static struct ctl_table fs_table[];
209 static struct ctl_table debug_table[];
210 static struct ctl_table dev_table[];
211 extern struct ctl_table random_table[];
212 #ifdef CONFIG_INOTIFY_USER
213 extern struct ctl_table inotify_table[];
214 #endif
215 #ifdef CONFIG_EPOLL
216 extern struct ctl_table epoll_table[];
217 #endif
219 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
220 int sysctl_legacy_va_layout;
221 #endif
223 /* The default sysctl tables: */
225 static struct ctl_table root_table[] = {
227 .procname = "kernel",
228 .mode = 0555,
229 .child = kern_table,
232 .procname = "vm",
233 .mode = 0555,
234 .child = vm_table,
237 .procname = "fs",
238 .mode = 0555,
239 .child = fs_table,
242 .procname = "debug",
243 .mode = 0555,
244 .child = debug_table,
247 .procname = "dev",
248 .mode = 0555,
249 .child = dev_table,
252 * NOTE: do not add new entries to this table unless you have read
253 * Documentation/sysctl/ctl_unnumbered.txt
258 #ifdef CONFIG_SCHED_DEBUG
259 static int min_sched_granularity_ns = 100000; /* 100 usecs */
260 static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
261 static int min_wakeup_granularity_ns; /* 0 usecs */
262 static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
263 static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
264 static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
265 static int min_sched_shares_ratelimit = 100000; /* 100 usec */
266 static int max_sched_shares_ratelimit = NSEC_PER_SEC; /* 1 second */
267 #endif
269 #ifdef CONFIG_COMPACTION
270 static int min_extfrag_threshold;
271 static int max_extfrag_threshold = 1000;
272 #endif
274 static struct ctl_table kern_table[] = {
276 .procname = "sched_child_runs_first",
277 .data = &sysctl_sched_child_runs_first,
278 .maxlen = sizeof(unsigned int),
279 .mode = 0644,
280 .proc_handler = proc_dointvec,
282 #ifdef CONFIG_SCHED_DEBUG
284 .procname = "sched_min_granularity_ns",
285 .data = &sysctl_sched_min_granularity,
286 .maxlen = sizeof(unsigned int),
287 .mode = 0644,
288 .proc_handler = sched_proc_update_handler,
289 .extra1 = &min_sched_granularity_ns,
290 .extra2 = &max_sched_granularity_ns,
293 .procname = "sched_latency_ns",
294 .data = &sysctl_sched_latency,
295 .maxlen = sizeof(unsigned int),
296 .mode = 0644,
297 .proc_handler = sched_proc_update_handler,
298 .extra1 = &min_sched_granularity_ns,
299 .extra2 = &max_sched_granularity_ns,
302 .procname = "sched_wakeup_granularity_ns",
303 .data = &sysctl_sched_wakeup_granularity,
304 .maxlen = sizeof(unsigned int),
305 .mode = 0644,
306 .proc_handler = sched_proc_update_handler,
307 .extra1 = &min_wakeup_granularity_ns,
308 .extra2 = &max_wakeup_granularity_ns,
311 .procname = "sched_shares_ratelimit",
312 .data = &sysctl_sched_shares_ratelimit,
313 .maxlen = sizeof(unsigned int),
314 .mode = 0644,
315 .proc_handler = sched_proc_update_handler,
316 .extra1 = &min_sched_shares_ratelimit,
317 .extra2 = &max_sched_shares_ratelimit,
320 .procname = "sched_tunable_scaling",
321 .data = &sysctl_sched_tunable_scaling,
322 .maxlen = sizeof(enum sched_tunable_scaling),
323 .mode = 0644,
324 .proc_handler = sched_proc_update_handler,
325 .extra1 = &min_sched_tunable_scaling,
326 .extra2 = &max_sched_tunable_scaling,
329 .procname = "sched_shares_thresh",
330 .data = &sysctl_sched_shares_thresh,
331 .maxlen = sizeof(unsigned int),
332 .mode = 0644,
333 .proc_handler = proc_dointvec_minmax,
334 .extra1 = &zero,
337 .procname = "sched_migration_cost",
338 .data = &sysctl_sched_migration_cost,
339 .maxlen = sizeof(unsigned int),
340 .mode = 0644,
341 .proc_handler = proc_dointvec,
344 .procname = "sched_nr_migrate",
345 .data = &sysctl_sched_nr_migrate,
346 .maxlen = sizeof(unsigned int),
347 .mode = 0644,
348 .proc_handler = proc_dointvec,
351 .procname = "sched_time_avg",
352 .data = &sysctl_sched_time_avg,
353 .maxlen = sizeof(unsigned int),
354 .mode = 0644,
355 .proc_handler = proc_dointvec,
358 .procname = "timer_migration",
359 .data = &sysctl_timer_migration,
360 .maxlen = sizeof(unsigned int),
361 .mode = 0644,
362 .proc_handler = proc_dointvec_minmax,
363 .extra1 = &zero,
364 .extra2 = &one,
366 #endif
368 .procname = "sched_rt_period_us",
369 .data = &sysctl_sched_rt_period,
370 .maxlen = sizeof(unsigned int),
371 .mode = 0644,
372 .proc_handler = sched_rt_handler,
375 .procname = "sched_rt_runtime_us",
376 .data = &sysctl_sched_rt_runtime,
377 .maxlen = sizeof(int),
378 .mode = 0644,
379 .proc_handler = sched_rt_handler,
382 .procname = "sched_compat_yield",
383 .data = &sysctl_sched_compat_yield,
384 .maxlen = sizeof(unsigned int),
385 .mode = 0644,
386 .proc_handler = proc_dointvec,
388 #ifdef CONFIG_PROVE_LOCKING
390 .procname = "prove_locking",
391 .data = &prove_locking,
392 .maxlen = sizeof(int),
393 .mode = 0644,
394 .proc_handler = proc_dointvec,
396 #endif
397 #ifdef CONFIG_LOCK_STAT
399 .procname = "lock_stat",
400 .data = &lock_stat,
401 .maxlen = sizeof(int),
402 .mode = 0644,
403 .proc_handler = proc_dointvec,
405 #endif
407 .procname = "panic",
408 .data = &panic_timeout,
409 .maxlen = sizeof(int),
410 .mode = 0644,
411 .proc_handler = proc_dointvec,
414 .procname = "core_uses_pid",
415 .data = &core_uses_pid,
416 .maxlen = sizeof(int),
417 .mode = 0644,
418 .proc_handler = proc_dointvec,
421 .procname = "core_pattern",
422 .data = core_pattern,
423 .maxlen = CORENAME_MAX_SIZE,
424 .mode = 0644,
425 .proc_handler = proc_dostring,
428 .procname = "core_pipe_limit",
429 .data = &core_pipe_limit,
430 .maxlen = sizeof(unsigned int),
431 .mode = 0644,
432 .proc_handler = proc_dointvec,
434 #ifdef CONFIG_PROC_SYSCTL
436 .procname = "tainted",
437 .maxlen = sizeof(long),
438 .mode = 0644,
439 .proc_handler = proc_taint,
441 #endif
442 #ifdef CONFIG_LATENCYTOP
444 .procname = "latencytop",
445 .data = &latencytop_enabled,
446 .maxlen = sizeof(int),
447 .mode = 0644,
448 .proc_handler = proc_dointvec,
450 #endif
451 #ifdef CONFIG_BLK_DEV_INITRD
453 .procname = "real-root-dev",
454 .data = &real_root_dev,
455 .maxlen = sizeof(int),
456 .mode = 0644,
457 .proc_handler = proc_dointvec,
459 #endif
461 .procname = "print-fatal-signals",
462 .data = &print_fatal_signals,
463 .maxlen = sizeof(int),
464 .mode = 0644,
465 .proc_handler = proc_dointvec,
467 #ifdef CONFIG_SPARC
469 .procname = "reboot-cmd",
470 .data = reboot_command,
471 .maxlen = 256,
472 .mode = 0644,
473 .proc_handler = proc_dostring,
476 .procname = "stop-a",
477 .data = &stop_a_enabled,
478 .maxlen = sizeof (int),
479 .mode = 0644,
480 .proc_handler = proc_dointvec,
483 .procname = "scons-poweroff",
484 .data = &scons_pwroff,
485 .maxlen = sizeof (int),
486 .mode = 0644,
487 .proc_handler = proc_dointvec,
489 #endif
490 #ifdef CONFIG_SPARC64
492 .procname = "tsb-ratio",
493 .data = &sysctl_tsb_ratio,
494 .maxlen = sizeof (int),
495 .mode = 0644,
496 .proc_handler = proc_dointvec,
498 #endif
499 #ifdef __hppa__
501 .procname = "soft-power",
502 .data = &pwrsw_enabled,
503 .maxlen = sizeof (int),
504 .mode = 0644,
505 .proc_handler = proc_dointvec,
508 .procname = "unaligned-trap",
509 .data = &unaligned_enabled,
510 .maxlen = sizeof (int),
511 .mode = 0644,
512 .proc_handler = proc_dointvec,
514 #endif
516 .procname = "ctrl-alt-del",
517 .data = &C_A_D,
518 .maxlen = sizeof(int),
519 .mode = 0644,
520 .proc_handler = proc_dointvec,
522 #ifdef CONFIG_FUNCTION_TRACER
524 .procname = "ftrace_enabled",
525 .data = &ftrace_enabled,
526 .maxlen = sizeof(int),
527 .mode = 0644,
528 .proc_handler = ftrace_enable_sysctl,
530 #endif
531 #ifdef CONFIG_STACK_TRACER
533 .procname = "stack_tracer_enabled",
534 .data = &stack_tracer_enabled,
535 .maxlen = sizeof(int),
536 .mode = 0644,
537 .proc_handler = stack_trace_sysctl,
539 #endif
540 #ifdef CONFIG_TRACING
542 .procname = "ftrace_dump_on_oops",
543 .data = &ftrace_dump_on_oops,
544 .maxlen = sizeof(int),
545 .mode = 0644,
546 .proc_handler = proc_dointvec,
548 #endif
549 #ifdef CONFIG_MODULES
551 .procname = "modprobe",
552 .data = &modprobe_path,
553 .maxlen = KMOD_PATH_LEN,
554 .mode = 0644,
555 .proc_handler = proc_dostring,
558 .procname = "modules_disabled",
559 .data = &modules_disabled,
560 .maxlen = sizeof(int),
561 .mode = 0644,
562 /* only handle a transition from default "0" to "1" */
563 .proc_handler = proc_dointvec_minmax,
564 .extra1 = &one,
565 .extra2 = &one,
567 #endif
568 #ifdef CONFIG_HOTPLUG
570 .procname = "hotplug",
571 .data = &uevent_helper,
572 .maxlen = UEVENT_HELPER_PATH_LEN,
573 .mode = 0644,
574 .proc_handler = proc_dostring,
576 #endif
577 #ifdef CONFIG_CHR_DEV_SG
579 .procname = "sg-big-buff",
580 .data = &sg_big_buff,
581 .maxlen = sizeof (int),
582 .mode = 0444,
583 .proc_handler = proc_dointvec,
585 #endif
586 #ifdef CONFIG_BSD_PROCESS_ACCT
588 .procname = "acct",
589 .data = &acct_parm,
590 .maxlen = 3*sizeof(int),
591 .mode = 0644,
592 .proc_handler = proc_dointvec,
594 #endif
595 #ifdef CONFIG_MAGIC_SYSRQ
597 .procname = "sysrq",
598 .data = &__sysrq_enabled,
599 .maxlen = sizeof (int),
600 .mode = 0644,
601 .proc_handler = sysrq_sysctl_handler,
603 #endif
604 #ifdef CONFIG_PROC_SYSCTL
606 .procname = "cad_pid",
607 .data = NULL,
608 .maxlen = sizeof (int),
609 .mode = 0600,
610 .proc_handler = proc_do_cad_pid,
612 #endif
614 .procname = "threads-max",
615 .data = &max_threads,
616 .maxlen = sizeof(int),
617 .mode = 0644,
618 .proc_handler = proc_dointvec,
621 .procname = "random",
622 .mode = 0555,
623 .child = random_table,
626 .procname = "overflowuid",
627 .data = &overflowuid,
628 .maxlen = sizeof(int),
629 .mode = 0644,
630 .proc_handler = proc_dointvec_minmax,
631 .extra1 = &minolduid,
632 .extra2 = &maxolduid,
635 .procname = "overflowgid",
636 .data = &overflowgid,
637 .maxlen = sizeof(int),
638 .mode = 0644,
639 .proc_handler = proc_dointvec_minmax,
640 .extra1 = &minolduid,
641 .extra2 = &maxolduid,
643 #ifdef CONFIG_S390
644 #ifdef CONFIG_MATHEMU
646 .procname = "ieee_emulation_warnings",
647 .data = &sysctl_ieee_emulation_warnings,
648 .maxlen = sizeof(int),
649 .mode = 0644,
650 .proc_handler = proc_dointvec,
652 #endif
654 .procname = "userprocess_debug",
655 .data = &show_unhandled_signals,
656 .maxlen = sizeof(int),
657 .mode = 0644,
658 .proc_handler = proc_dointvec,
660 #endif
662 .procname = "pid_max",
663 .data = &pid_max,
664 .maxlen = sizeof (int),
665 .mode = 0644,
666 .proc_handler = proc_dointvec_minmax,
667 .extra1 = &pid_max_min,
668 .extra2 = &pid_max_max,
671 .procname = "panic_on_oops",
672 .data = &panic_on_oops,
673 .maxlen = sizeof(int),
674 .mode = 0644,
675 .proc_handler = proc_dointvec,
677 #if defined CONFIG_PRINTK
679 .procname = "printk",
680 .data = &console_loglevel,
681 .maxlen = 4*sizeof(int),
682 .mode = 0644,
683 .proc_handler = proc_dointvec,
686 .procname = "printk_ratelimit",
687 .data = &printk_ratelimit_state.interval,
688 .maxlen = sizeof(int),
689 .mode = 0644,
690 .proc_handler = proc_dointvec_jiffies,
693 .procname = "printk_ratelimit_burst",
694 .data = &printk_ratelimit_state.burst,
695 .maxlen = sizeof(int),
696 .mode = 0644,
697 .proc_handler = proc_dointvec,
700 .procname = "printk_delay",
701 .data = &printk_delay_msec,
702 .maxlen = sizeof(int),
703 .mode = 0644,
704 .proc_handler = proc_dointvec_minmax,
705 .extra1 = &zero,
706 .extra2 = &ten_thousand,
708 #endif
710 .procname = "ngroups_max",
711 .data = &ngroups_max,
712 .maxlen = sizeof (int),
713 .mode = 0444,
714 .proc_handler = proc_dointvec,
716 #if defined(CONFIG_LOCKUP_DETECTOR)
718 .procname = "watchdog",
719 .data = &watchdog_enabled,
720 .maxlen = sizeof (int),
721 .mode = 0644,
722 .proc_handler = proc_dowatchdog_enabled,
725 .procname = "watchdog_thresh",
726 .data = &softlockup_thresh,
727 .maxlen = sizeof(int),
728 .mode = 0644,
729 .proc_handler = proc_dowatchdog_thresh,
730 .extra1 = &neg_one,
731 .extra2 = &sixty,
734 .procname = "softlockup_panic",
735 .data = &softlockup_panic,
736 .maxlen = sizeof(int),
737 .mode = 0644,
738 .proc_handler = proc_dointvec_minmax,
739 .extra1 = &zero,
740 .extra2 = &one,
742 #endif
743 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) && !defined(CONFIG_LOCKUP_DETECTOR)
745 .procname = "unknown_nmi_panic",
746 .data = &unknown_nmi_panic,
747 .maxlen = sizeof (int),
748 .mode = 0644,
749 .proc_handler = proc_dointvec,
752 .procname = "nmi_watchdog",
753 .data = &nmi_watchdog_enabled,
754 .maxlen = sizeof (int),
755 .mode = 0644,
756 .proc_handler = proc_nmi_enabled,
758 #endif
759 #if defined(CONFIG_X86)
761 .procname = "panic_on_unrecovered_nmi",
762 .data = &panic_on_unrecovered_nmi,
763 .maxlen = sizeof(int),
764 .mode = 0644,
765 .proc_handler = proc_dointvec,
768 .procname = "panic_on_io_nmi",
769 .data = &panic_on_io_nmi,
770 .maxlen = sizeof(int),
771 .mode = 0644,
772 .proc_handler = proc_dointvec,
775 .procname = "bootloader_type",
776 .data = &bootloader_type,
777 .maxlen = sizeof (int),
778 .mode = 0444,
779 .proc_handler = proc_dointvec,
782 .procname = "bootloader_version",
783 .data = &bootloader_version,
784 .maxlen = sizeof (int),
785 .mode = 0444,
786 .proc_handler = proc_dointvec,
789 .procname = "kstack_depth_to_print",
790 .data = &kstack_depth_to_print,
791 .maxlen = sizeof(int),
792 .mode = 0644,
793 .proc_handler = proc_dointvec,
796 .procname = "io_delay_type",
797 .data = &io_delay_type,
798 .maxlen = sizeof(int),
799 .mode = 0644,
800 .proc_handler = proc_dointvec,
802 #endif
803 #if defined(CONFIG_MMU)
805 .procname = "randomize_va_space",
806 .data = &randomize_va_space,
807 .maxlen = sizeof(int),
808 .mode = 0644,
809 .proc_handler = proc_dointvec,
811 #endif
812 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
814 .procname = "spin_retry",
815 .data = &spin_retry,
816 .maxlen = sizeof (int),
817 .mode = 0644,
818 .proc_handler = proc_dointvec,
820 #endif
821 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
823 .procname = "acpi_video_flags",
824 .data = &acpi_realmode_flags,
825 .maxlen = sizeof (unsigned long),
826 .mode = 0644,
827 .proc_handler = proc_doulongvec_minmax,
829 #endif
830 #ifdef CONFIG_IA64
832 .procname = "ignore-unaligned-usertrap",
833 .data = &no_unaligned_warning,
834 .maxlen = sizeof (int),
835 .mode = 0644,
836 .proc_handler = proc_dointvec,
839 .procname = "unaligned-dump-stack",
840 .data = &unaligned_dump_stack,
841 .maxlen = sizeof (int),
842 .mode = 0644,
843 .proc_handler = proc_dointvec,
845 #endif
846 #ifdef CONFIG_DETECT_HUNG_TASK
848 .procname = "hung_task_panic",
849 .data = &sysctl_hung_task_panic,
850 .maxlen = sizeof(int),
851 .mode = 0644,
852 .proc_handler = proc_dointvec_minmax,
853 .extra1 = &zero,
854 .extra2 = &one,
857 .procname = "hung_task_check_count",
858 .data = &sysctl_hung_task_check_count,
859 .maxlen = sizeof(unsigned long),
860 .mode = 0644,
861 .proc_handler = proc_doulongvec_minmax,
864 .procname = "hung_task_timeout_secs",
865 .data = &sysctl_hung_task_timeout_secs,
866 .maxlen = sizeof(unsigned long),
867 .mode = 0644,
868 .proc_handler = proc_dohung_task_timeout_secs,
871 .procname = "hung_task_warnings",
872 .data = &sysctl_hung_task_warnings,
873 .maxlen = sizeof(unsigned long),
874 .mode = 0644,
875 .proc_handler = proc_doulongvec_minmax,
877 #endif
878 #ifdef CONFIG_COMPAT
880 .procname = "compat-log",
881 .data = &compat_log,
882 .maxlen = sizeof (int),
883 .mode = 0644,
884 .proc_handler = proc_dointvec,
886 #endif
887 #ifdef CONFIG_RT_MUTEXES
889 .procname = "max_lock_depth",
890 .data = &max_lock_depth,
891 .maxlen = sizeof(int),
892 .mode = 0644,
893 .proc_handler = proc_dointvec,
895 #endif
897 .procname = "poweroff_cmd",
898 .data = &poweroff_cmd,
899 .maxlen = POWEROFF_CMD_PATH_LEN,
900 .mode = 0644,
901 .proc_handler = proc_dostring,
903 #ifdef CONFIG_KEYS
905 .procname = "keys",
906 .mode = 0555,
907 .child = key_sysctls,
909 #endif
910 #ifdef CONFIG_RCU_TORTURE_TEST
912 .procname = "rcutorture_runnable",
913 .data = &rcutorture_runnable,
914 .maxlen = sizeof(int),
915 .mode = 0644,
916 .proc_handler = proc_dointvec,
918 #endif
919 #ifdef CONFIG_PERF_EVENTS
921 .procname = "perf_event_paranoid",
922 .data = &sysctl_perf_event_paranoid,
923 .maxlen = sizeof(sysctl_perf_event_paranoid),
924 .mode = 0644,
925 .proc_handler = proc_dointvec,
928 .procname = "perf_event_mlock_kb",
929 .data = &sysctl_perf_event_mlock,
930 .maxlen = sizeof(sysctl_perf_event_mlock),
931 .mode = 0644,
932 .proc_handler = proc_dointvec,
935 .procname = "perf_event_max_sample_rate",
936 .data = &sysctl_perf_event_sample_rate,
937 .maxlen = sizeof(sysctl_perf_event_sample_rate),
938 .mode = 0644,
939 .proc_handler = proc_dointvec,
941 #endif
942 #ifdef CONFIG_KMEMCHECK
944 .procname = "kmemcheck",
945 .data = &kmemcheck_enabled,
946 .maxlen = sizeof(int),
947 .mode = 0644,
948 .proc_handler = proc_dointvec,
950 #endif
951 #ifdef CONFIG_BLOCK
953 .procname = "blk_iopoll",
954 .data = &blk_iopoll_enabled,
955 .maxlen = sizeof(int),
956 .mode = 0644,
957 .proc_handler = proc_dointvec,
959 #endif
961 * NOTE: do not add new entries to this table unless you have read
962 * Documentation/sysctl/ctl_unnumbered.txt
967 static struct ctl_table vm_table[] = {
969 .procname = "overcommit_memory",
970 .data = &sysctl_overcommit_memory,
971 .maxlen = sizeof(sysctl_overcommit_memory),
972 .mode = 0644,
973 .proc_handler = proc_dointvec,
976 .procname = "panic_on_oom",
977 .data = &sysctl_panic_on_oom,
978 .maxlen = sizeof(sysctl_panic_on_oom),
979 .mode = 0644,
980 .proc_handler = proc_dointvec,
983 .procname = "oom_kill_allocating_task",
984 .data = &sysctl_oom_kill_allocating_task,
985 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
986 .mode = 0644,
987 .proc_handler = proc_dointvec,
990 .procname = "oom_dump_tasks",
991 .data = &sysctl_oom_dump_tasks,
992 .maxlen = sizeof(sysctl_oom_dump_tasks),
993 .mode = 0644,
994 .proc_handler = proc_dointvec,
997 .procname = "overcommit_ratio",
998 .data = &sysctl_overcommit_ratio,
999 .maxlen = sizeof(sysctl_overcommit_ratio),
1000 .mode = 0644,
1001 .proc_handler = proc_dointvec,
1004 .procname = "page-cluster",
1005 .data = &page_cluster,
1006 .maxlen = sizeof(int),
1007 .mode = 0644,
1008 .proc_handler = proc_dointvec,
1011 .procname = "dirty_background_ratio",
1012 .data = &dirty_background_ratio,
1013 .maxlen = sizeof(dirty_background_ratio),
1014 .mode = 0644,
1015 .proc_handler = dirty_background_ratio_handler,
1016 .extra1 = &zero,
1017 .extra2 = &one_hundred,
1020 .procname = "dirty_background_bytes",
1021 .data = &dirty_background_bytes,
1022 .maxlen = sizeof(dirty_background_bytes),
1023 .mode = 0644,
1024 .proc_handler = dirty_background_bytes_handler,
1025 .extra1 = &one_ul,
1028 .procname = "dirty_ratio",
1029 .data = &vm_dirty_ratio,
1030 .maxlen = sizeof(vm_dirty_ratio),
1031 .mode = 0644,
1032 .proc_handler = dirty_ratio_handler,
1033 .extra1 = &zero,
1034 .extra2 = &one_hundred,
1037 .procname = "dirty_bytes",
1038 .data = &vm_dirty_bytes,
1039 .maxlen = sizeof(vm_dirty_bytes),
1040 .mode = 0644,
1041 .proc_handler = dirty_bytes_handler,
1042 .extra1 = &dirty_bytes_min,
1045 .procname = "dirty_writeback_centisecs",
1046 .data = &dirty_writeback_interval,
1047 .maxlen = sizeof(dirty_writeback_interval),
1048 .mode = 0644,
1049 .proc_handler = dirty_writeback_centisecs_handler,
1052 .procname = "dirty_expire_centisecs",
1053 .data = &dirty_expire_interval,
1054 .maxlen = sizeof(dirty_expire_interval),
1055 .mode = 0644,
1056 .proc_handler = proc_dointvec,
1059 .procname = "nr_pdflush_threads",
1060 .data = &nr_pdflush_threads,
1061 .maxlen = sizeof nr_pdflush_threads,
1062 .mode = 0444 /* read-only*/,
1063 .proc_handler = proc_dointvec,
1066 .procname = "swappiness",
1067 .data = &vm_swappiness,
1068 .maxlen = sizeof(vm_swappiness),
1069 .mode = 0644,
1070 .proc_handler = proc_dointvec_minmax,
1071 .extra1 = &zero,
1072 .extra2 = &one_hundred,
1074 #ifdef CONFIG_HUGETLB_PAGE
1076 .procname = "nr_hugepages",
1077 .data = NULL,
1078 .maxlen = sizeof(unsigned long),
1079 .mode = 0644,
1080 .proc_handler = hugetlb_sysctl_handler,
1081 .extra1 = (void *)&hugetlb_zero,
1082 .extra2 = (void *)&hugetlb_infinity,
1084 #ifdef CONFIG_NUMA
1086 .procname = "nr_hugepages_mempolicy",
1087 .data = NULL,
1088 .maxlen = sizeof(unsigned long),
1089 .mode = 0644,
1090 .proc_handler = &hugetlb_mempolicy_sysctl_handler,
1091 .extra1 = (void *)&hugetlb_zero,
1092 .extra2 = (void *)&hugetlb_infinity,
1094 #endif
1096 .procname = "hugetlb_shm_group",
1097 .data = &sysctl_hugetlb_shm_group,
1098 .maxlen = sizeof(gid_t),
1099 .mode = 0644,
1100 .proc_handler = proc_dointvec,
1103 .procname = "hugepages_treat_as_movable",
1104 .data = &hugepages_treat_as_movable,
1105 .maxlen = sizeof(int),
1106 .mode = 0644,
1107 .proc_handler = hugetlb_treat_movable_handler,
1110 .procname = "nr_overcommit_hugepages",
1111 .data = NULL,
1112 .maxlen = sizeof(unsigned long),
1113 .mode = 0644,
1114 .proc_handler = hugetlb_overcommit_handler,
1115 .extra1 = (void *)&hugetlb_zero,
1116 .extra2 = (void *)&hugetlb_infinity,
1118 #endif
1120 .procname = "lowmem_reserve_ratio",
1121 .data = &sysctl_lowmem_reserve_ratio,
1122 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1123 .mode = 0644,
1124 .proc_handler = lowmem_reserve_ratio_sysctl_handler,
1127 .procname = "drop_caches",
1128 .data = &sysctl_drop_caches,
1129 .maxlen = sizeof(int),
1130 .mode = 0644,
1131 .proc_handler = drop_caches_sysctl_handler,
1133 #ifdef CONFIG_COMPACTION
1135 .procname = "compact_memory",
1136 .data = &sysctl_compact_memory,
1137 .maxlen = sizeof(int),
1138 .mode = 0200,
1139 .proc_handler = sysctl_compaction_handler,
1142 .procname = "extfrag_threshold",
1143 .data = &sysctl_extfrag_threshold,
1144 .maxlen = sizeof(int),
1145 .mode = 0644,
1146 .proc_handler = sysctl_extfrag_handler,
1147 .extra1 = &min_extfrag_threshold,
1148 .extra2 = &max_extfrag_threshold,
1151 #endif /* CONFIG_COMPACTION */
1153 .procname = "min_free_kbytes",
1154 .data = &min_free_kbytes,
1155 .maxlen = sizeof(min_free_kbytes),
1156 .mode = 0644,
1157 .proc_handler = min_free_kbytes_sysctl_handler,
1158 .extra1 = &zero,
1161 .procname = "percpu_pagelist_fraction",
1162 .data = &percpu_pagelist_fraction,
1163 .maxlen = sizeof(percpu_pagelist_fraction),
1164 .mode = 0644,
1165 .proc_handler = percpu_pagelist_fraction_sysctl_handler,
1166 .extra1 = &min_percpu_pagelist_fract,
1168 #ifdef CONFIG_MMU
1170 .procname = "max_map_count",
1171 .data = &sysctl_max_map_count,
1172 .maxlen = sizeof(sysctl_max_map_count),
1173 .mode = 0644,
1174 .proc_handler = proc_dointvec_minmax,
1175 .extra1 = &zero,
1177 #else
1179 .procname = "nr_trim_pages",
1180 .data = &sysctl_nr_trim_pages,
1181 .maxlen = sizeof(sysctl_nr_trim_pages),
1182 .mode = 0644,
1183 .proc_handler = proc_dointvec_minmax,
1184 .extra1 = &zero,
1186 #endif
1188 .procname = "laptop_mode",
1189 .data = &laptop_mode,
1190 .maxlen = sizeof(laptop_mode),
1191 .mode = 0644,
1192 .proc_handler = proc_dointvec_jiffies,
1195 .procname = "block_dump",
1196 .data = &block_dump,
1197 .maxlen = sizeof(block_dump),
1198 .mode = 0644,
1199 .proc_handler = proc_dointvec,
1200 .extra1 = &zero,
1203 .procname = "vfs_cache_pressure",
1204 .data = &sysctl_vfs_cache_pressure,
1205 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1206 .mode = 0644,
1207 .proc_handler = proc_dointvec,
1208 .extra1 = &zero,
1210 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1212 .procname = "legacy_va_layout",
1213 .data = &sysctl_legacy_va_layout,
1214 .maxlen = sizeof(sysctl_legacy_va_layout),
1215 .mode = 0644,
1216 .proc_handler = proc_dointvec,
1217 .extra1 = &zero,
1219 #endif
1220 #ifdef CONFIG_NUMA
1222 .procname = "zone_reclaim_mode",
1223 .data = &zone_reclaim_mode,
1224 .maxlen = sizeof(zone_reclaim_mode),
1225 .mode = 0644,
1226 .proc_handler = proc_dointvec,
1227 .extra1 = &zero,
1230 .procname = "min_unmapped_ratio",
1231 .data = &sysctl_min_unmapped_ratio,
1232 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1233 .mode = 0644,
1234 .proc_handler = sysctl_min_unmapped_ratio_sysctl_handler,
1235 .extra1 = &zero,
1236 .extra2 = &one_hundred,
1239 .procname = "min_slab_ratio",
1240 .data = &sysctl_min_slab_ratio,
1241 .maxlen = sizeof(sysctl_min_slab_ratio),
1242 .mode = 0644,
1243 .proc_handler = sysctl_min_slab_ratio_sysctl_handler,
1244 .extra1 = &zero,
1245 .extra2 = &one_hundred,
1247 #endif
1248 #ifdef CONFIG_SMP
1250 .procname = "stat_interval",
1251 .data = &sysctl_stat_interval,
1252 .maxlen = sizeof(sysctl_stat_interval),
1253 .mode = 0644,
1254 .proc_handler = proc_dointvec_jiffies,
1256 #endif
1257 #ifdef CONFIG_MMU
1259 .procname = "mmap_min_addr",
1260 .data = &dac_mmap_min_addr,
1261 .maxlen = sizeof(unsigned long),
1262 .mode = 0644,
1263 .proc_handler = mmap_min_addr_handler,
1265 #endif
1266 #ifdef CONFIG_NUMA
1268 .procname = "numa_zonelist_order",
1269 .data = &numa_zonelist_order,
1270 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1271 .mode = 0644,
1272 .proc_handler = numa_zonelist_order_handler,
1274 #endif
1275 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1276 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1278 .procname = "vdso_enabled",
1279 .data = &vdso_enabled,
1280 .maxlen = sizeof(vdso_enabled),
1281 .mode = 0644,
1282 .proc_handler = proc_dointvec,
1283 .extra1 = &zero,
1285 #endif
1286 #ifdef CONFIG_HIGHMEM
1288 .procname = "highmem_is_dirtyable",
1289 .data = &vm_highmem_is_dirtyable,
1290 .maxlen = sizeof(vm_highmem_is_dirtyable),
1291 .mode = 0644,
1292 .proc_handler = proc_dointvec_minmax,
1293 .extra1 = &zero,
1294 .extra2 = &one,
1296 #endif
1298 .procname = "scan_unevictable_pages",
1299 .data = &scan_unevictable_pages,
1300 .maxlen = sizeof(scan_unevictable_pages),
1301 .mode = 0644,
1302 .proc_handler = scan_unevictable_handler,
1304 #ifdef CONFIG_MEMORY_FAILURE
1306 .procname = "memory_failure_early_kill",
1307 .data = &sysctl_memory_failure_early_kill,
1308 .maxlen = sizeof(sysctl_memory_failure_early_kill),
1309 .mode = 0644,
1310 .proc_handler = proc_dointvec_minmax,
1311 .extra1 = &zero,
1312 .extra2 = &one,
1315 .procname = "memory_failure_recovery",
1316 .data = &sysctl_memory_failure_recovery,
1317 .maxlen = sizeof(sysctl_memory_failure_recovery),
1318 .mode = 0644,
1319 .proc_handler = proc_dointvec_minmax,
1320 .extra1 = &zero,
1321 .extra2 = &one,
1323 #endif
1326 * NOTE: do not add new entries to this table unless you have read
1327 * Documentation/sysctl/ctl_unnumbered.txt
1332 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1333 static struct ctl_table binfmt_misc_table[] = {
1336 #endif
1338 static struct ctl_table fs_table[] = {
1340 .procname = "inode-nr",
1341 .data = &inodes_stat,
1342 .maxlen = 2*sizeof(int),
1343 .mode = 0444,
1344 .proc_handler = proc_dointvec,
1347 .procname = "inode-state",
1348 .data = &inodes_stat,
1349 .maxlen = 7*sizeof(int),
1350 .mode = 0444,
1351 .proc_handler = proc_dointvec,
1354 .procname = "file-nr",
1355 .data = &files_stat,
1356 .maxlen = 3*sizeof(int),
1357 .mode = 0444,
1358 .proc_handler = proc_nr_files,
1361 .procname = "file-max",
1362 .data = &files_stat.max_files,
1363 .maxlen = sizeof(int),
1364 .mode = 0644,
1365 .proc_handler = proc_dointvec,
1368 .procname = "nr_open",
1369 .data = &sysctl_nr_open,
1370 .maxlen = sizeof(int),
1371 .mode = 0644,
1372 .proc_handler = proc_dointvec_minmax,
1373 .extra1 = &sysctl_nr_open_min,
1374 .extra2 = &sysctl_nr_open_max,
1377 .procname = "dentry-state",
1378 .data = &dentry_stat,
1379 .maxlen = 6*sizeof(int),
1380 .mode = 0444,
1381 .proc_handler = proc_dointvec,
1384 .procname = "overflowuid",
1385 .data = &fs_overflowuid,
1386 .maxlen = sizeof(int),
1387 .mode = 0644,
1388 .proc_handler = proc_dointvec_minmax,
1389 .extra1 = &minolduid,
1390 .extra2 = &maxolduid,
1393 .procname = "overflowgid",
1394 .data = &fs_overflowgid,
1395 .maxlen = sizeof(int),
1396 .mode = 0644,
1397 .proc_handler = proc_dointvec_minmax,
1398 .extra1 = &minolduid,
1399 .extra2 = &maxolduid,
1401 #ifdef CONFIG_FILE_LOCKING
1403 .procname = "leases-enable",
1404 .data = &leases_enable,
1405 .maxlen = sizeof(int),
1406 .mode = 0644,
1407 .proc_handler = proc_dointvec,
1409 #endif
1410 #ifdef CONFIG_DNOTIFY
1412 .procname = "dir-notify-enable",
1413 .data = &dir_notify_enable,
1414 .maxlen = sizeof(int),
1415 .mode = 0644,
1416 .proc_handler = proc_dointvec,
1418 #endif
1419 #ifdef CONFIG_MMU
1420 #ifdef CONFIG_FILE_LOCKING
1422 .procname = "lease-break-time",
1423 .data = &lease_break_time,
1424 .maxlen = sizeof(int),
1425 .mode = 0644,
1426 .proc_handler = proc_dointvec,
1428 #endif
1429 #ifdef CONFIG_AIO
1431 .procname = "aio-nr",
1432 .data = &aio_nr,
1433 .maxlen = sizeof(aio_nr),
1434 .mode = 0444,
1435 .proc_handler = proc_doulongvec_minmax,
1438 .procname = "aio-max-nr",
1439 .data = &aio_max_nr,
1440 .maxlen = sizeof(aio_max_nr),
1441 .mode = 0644,
1442 .proc_handler = proc_doulongvec_minmax,
1444 #endif /* CONFIG_AIO */
1445 #ifdef CONFIG_INOTIFY_USER
1447 .procname = "inotify",
1448 .mode = 0555,
1449 .child = inotify_table,
1451 #endif
1452 #ifdef CONFIG_EPOLL
1454 .procname = "epoll",
1455 .mode = 0555,
1456 .child = epoll_table,
1458 #endif
1459 #endif
1461 .procname = "suid_dumpable",
1462 .data = &suid_dumpable,
1463 .maxlen = sizeof(int),
1464 .mode = 0644,
1465 .proc_handler = proc_dointvec_minmax,
1466 .extra1 = &zero,
1467 .extra2 = &two,
1469 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1471 .procname = "binfmt_misc",
1472 .mode = 0555,
1473 .child = binfmt_misc_table,
1475 #endif
1477 .procname = "pipe-max-size",
1478 .data = &pipe_max_size,
1479 .maxlen = sizeof(int),
1480 .mode = 0644,
1481 .proc_handler = &pipe_proc_fn,
1482 .extra1 = &pipe_min_size,
1485 * NOTE: do not add new entries to this table unless you have read
1486 * Documentation/sysctl/ctl_unnumbered.txt
1491 static struct ctl_table debug_table[] = {
1492 #if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_SPARC) || \
1493 defined(CONFIG_S390)
1495 .procname = "exception-trace",
1496 .data = &show_unhandled_signals,
1497 .maxlen = sizeof(int),
1498 .mode = 0644,
1499 .proc_handler = proc_dointvec
1501 #endif
1502 #if defined(CONFIG_OPTPROBES)
1504 .procname = "kprobes-optimization",
1505 .data = &sysctl_kprobes_optimization,
1506 .maxlen = sizeof(int),
1507 .mode = 0644,
1508 .proc_handler = proc_kprobes_optimization_handler,
1509 .extra1 = &zero,
1510 .extra2 = &one,
1512 #endif
1516 static struct ctl_table dev_table[] = {
1520 static DEFINE_SPINLOCK(sysctl_lock);
1522 /* called under sysctl_lock */
1523 static int use_table(struct ctl_table_header *p)
1525 if (unlikely(p->unregistering))
1526 return 0;
1527 p->used++;
1528 return 1;
1531 /* called under sysctl_lock */
1532 static void unuse_table(struct ctl_table_header *p)
1534 if (!--p->used)
1535 if (unlikely(p->unregistering))
1536 complete(p->unregistering);
1539 /* called under sysctl_lock, will reacquire if has to wait */
1540 static void start_unregistering(struct ctl_table_header *p)
1543 * if p->used is 0, nobody will ever touch that entry again;
1544 * we'll eliminate all paths to it before dropping sysctl_lock
1546 if (unlikely(p->used)) {
1547 struct completion wait;
1548 init_completion(&wait);
1549 p->unregistering = &wait;
1550 spin_unlock(&sysctl_lock);
1551 wait_for_completion(&wait);
1552 spin_lock(&sysctl_lock);
1553 } else {
1554 /* anything non-NULL; we'll never dereference it */
1555 p->unregistering = ERR_PTR(-EINVAL);
1558 * do not remove from the list until nobody holds it; walking the
1559 * list in do_sysctl() relies on that.
1561 list_del_init(&p->ctl_entry);
1564 void sysctl_head_get(struct ctl_table_header *head)
1566 spin_lock(&sysctl_lock);
1567 head->count++;
1568 spin_unlock(&sysctl_lock);
1571 void sysctl_head_put(struct ctl_table_header *head)
1573 spin_lock(&sysctl_lock);
1574 if (!--head->count)
1575 kfree(head);
1576 spin_unlock(&sysctl_lock);
1579 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1581 if (!head)
1582 BUG();
1583 spin_lock(&sysctl_lock);
1584 if (!use_table(head))
1585 head = ERR_PTR(-ENOENT);
1586 spin_unlock(&sysctl_lock);
1587 return head;
1590 void sysctl_head_finish(struct ctl_table_header *head)
1592 if (!head)
1593 return;
1594 spin_lock(&sysctl_lock);
1595 unuse_table(head);
1596 spin_unlock(&sysctl_lock);
1599 static struct ctl_table_set *
1600 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1602 struct ctl_table_set *set = &root->default_set;
1603 if (root->lookup)
1604 set = root->lookup(root, namespaces);
1605 return set;
1608 static struct list_head *
1609 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1611 struct ctl_table_set *set = lookup_header_set(root, namespaces);
1612 return &set->list;
1615 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1616 struct ctl_table_header *prev)
1618 struct ctl_table_root *root;
1619 struct list_head *header_list;
1620 struct ctl_table_header *head;
1621 struct list_head *tmp;
1623 spin_lock(&sysctl_lock);
1624 if (prev) {
1625 head = prev;
1626 tmp = &prev->ctl_entry;
1627 unuse_table(prev);
1628 goto next;
1630 tmp = &root_table_header.ctl_entry;
1631 for (;;) {
1632 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1634 if (!use_table(head))
1635 goto next;
1636 spin_unlock(&sysctl_lock);
1637 return head;
1638 next:
1639 root = head->root;
1640 tmp = tmp->next;
1641 header_list = lookup_header_list(root, namespaces);
1642 if (tmp != header_list)
1643 continue;
1645 do {
1646 root = list_entry(root->root_list.next,
1647 struct ctl_table_root, root_list);
1648 if (root == &sysctl_table_root)
1649 goto out;
1650 header_list = lookup_header_list(root, namespaces);
1651 } while (list_empty(header_list));
1652 tmp = header_list->next;
1654 out:
1655 spin_unlock(&sysctl_lock);
1656 return NULL;
1659 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1661 return __sysctl_head_next(current->nsproxy, prev);
1664 void register_sysctl_root(struct ctl_table_root *root)
1666 spin_lock(&sysctl_lock);
1667 list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1668 spin_unlock(&sysctl_lock);
1672 * sysctl_perm does NOT grant the superuser all rights automatically, because
1673 * some sysctl variables are readonly even to root.
1676 static int test_perm(int mode, int op)
1678 if (!current_euid())
1679 mode >>= 6;
1680 else if (in_egroup_p(0))
1681 mode >>= 3;
1682 if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1683 return 0;
1684 return -EACCES;
1687 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1689 int error;
1690 int mode;
1692 error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1693 if (error)
1694 return error;
1696 if (root->permissions)
1697 mode = root->permissions(root, current->nsproxy, table);
1698 else
1699 mode = table->mode;
1701 return test_perm(mode, op);
1704 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1706 for (; table->procname; table++) {
1707 table->parent = parent;
1708 if (table->child)
1709 sysctl_set_parent(table, table->child);
1713 static __init int sysctl_init(void)
1715 sysctl_set_parent(NULL, root_table);
1716 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1718 int err;
1719 err = sysctl_check_table(current->nsproxy, root_table);
1721 #endif
1722 return 0;
1725 core_initcall(sysctl_init);
1727 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1728 struct ctl_table *table)
1730 struct ctl_table *p;
1731 const char *s = branch->procname;
1733 /* branch should have named subdirectory as its first element */
1734 if (!s || !branch->child)
1735 return NULL;
1737 /* ... and nothing else */
1738 if (branch[1].procname)
1739 return NULL;
1741 /* table should contain subdirectory with the same name */
1742 for (p = table; p->procname; p++) {
1743 if (!p->child)
1744 continue;
1745 if (p->procname && strcmp(p->procname, s) == 0)
1746 return p;
1748 return NULL;
1751 /* see if attaching q to p would be an improvement */
1752 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1754 struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1755 struct ctl_table *next;
1756 int is_better = 0;
1757 int not_in_parent = !p->attached_by;
1759 while ((next = is_branch_in(by, to)) != NULL) {
1760 if (by == q->attached_by)
1761 is_better = 1;
1762 if (to == p->attached_by)
1763 not_in_parent = 1;
1764 by = by->child;
1765 to = next->child;
1768 if (is_better && not_in_parent) {
1769 q->attached_by = by;
1770 q->attached_to = to;
1771 q->parent = p;
1776 * __register_sysctl_paths - register a sysctl hierarchy
1777 * @root: List of sysctl headers to register on
1778 * @namespaces: Data to compute which lists of sysctl entries are visible
1779 * @path: The path to the directory the sysctl table is in.
1780 * @table: the top-level table structure
1782 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1783 * array. A completely 0 filled entry terminates the table.
1785 * The members of the &struct ctl_table structure are used as follows:
1787 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1788 * enter a sysctl file
1790 * data - a pointer to data for use by proc_handler
1792 * maxlen - the maximum size in bytes of the data
1794 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1796 * child - a pointer to the child sysctl table if this entry is a directory, or
1797 * %NULL.
1799 * proc_handler - the text handler routine (described below)
1801 * de - for internal use by the sysctl routines
1803 * extra1, extra2 - extra pointers usable by the proc handler routines
1805 * Leaf nodes in the sysctl tree will be represented by a single file
1806 * under /proc; non-leaf nodes will be represented by directories.
1808 * sysctl(2) can automatically manage read and write requests through
1809 * the sysctl table. The data and maxlen fields of the ctl_table
1810 * struct enable minimal validation of the values being written to be
1811 * performed, and the mode field allows minimal authentication.
1813 * There must be a proc_handler routine for any terminal nodes
1814 * mirrored under /proc/sys (non-terminals are handled by a built-in
1815 * directory handler). Several default handlers are available to
1816 * cover common cases -
1818 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1819 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1820 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1822 * It is the handler's job to read the input buffer from user memory
1823 * and process it. The handler should return 0 on success.
1825 * This routine returns %NULL on a failure to register, and a pointer
1826 * to the table header on success.
1828 struct ctl_table_header *__register_sysctl_paths(
1829 struct ctl_table_root *root,
1830 struct nsproxy *namespaces,
1831 const struct ctl_path *path, struct ctl_table *table)
1833 struct ctl_table_header *header;
1834 struct ctl_table *new, **prevp;
1835 unsigned int n, npath;
1836 struct ctl_table_set *set;
1838 /* Count the path components */
1839 for (npath = 0; path[npath].procname; ++npath)
1843 * For each path component, allocate a 2-element ctl_table array.
1844 * The first array element will be filled with the sysctl entry
1845 * for this, the second will be the sentinel (procname == 0).
1847 * We allocate everything in one go so that we don't have to
1848 * worry about freeing additional memory in unregister_sysctl_table.
1850 header = kzalloc(sizeof(struct ctl_table_header) +
1851 (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
1852 if (!header)
1853 return NULL;
1855 new = (struct ctl_table *) (header + 1);
1857 /* Now connect the dots */
1858 prevp = &header->ctl_table;
1859 for (n = 0; n < npath; ++n, ++path) {
1860 /* Copy the procname */
1861 new->procname = path->procname;
1862 new->mode = 0555;
1864 *prevp = new;
1865 prevp = &new->child;
1867 new += 2;
1869 *prevp = table;
1870 header->ctl_table_arg = table;
1872 INIT_LIST_HEAD(&header->ctl_entry);
1873 header->used = 0;
1874 header->unregistering = NULL;
1875 header->root = root;
1876 sysctl_set_parent(NULL, header->ctl_table);
1877 header->count = 1;
1878 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1879 if (sysctl_check_table(namespaces, header->ctl_table)) {
1880 kfree(header);
1881 return NULL;
1883 #endif
1884 spin_lock(&sysctl_lock);
1885 header->set = lookup_header_set(root, namespaces);
1886 header->attached_by = header->ctl_table;
1887 header->attached_to = root_table;
1888 header->parent = &root_table_header;
1889 for (set = header->set; set; set = set->parent) {
1890 struct ctl_table_header *p;
1891 list_for_each_entry(p, &set->list, ctl_entry) {
1892 if (p->unregistering)
1893 continue;
1894 try_attach(p, header);
1897 header->parent->count++;
1898 list_add_tail(&header->ctl_entry, &header->set->list);
1899 spin_unlock(&sysctl_lock);
1901 return header;
1905 * register_sysctl_table_path - register a sysctl table hierarchy
1906 * @path: The path to the directory the sysctl table is in.
1907 * @table: the top-level table structure
1909 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1910 * array. A completely 0 filled entry terminates the table.
1912 * See __register_sysctl_paths for more details.
1914 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1915 struct ctl_table *table)
1917 return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
1918 path, table);
1922 * register_sysctl_table - register a sysctl table hierarchy
1923 * @table: the top-level table structure
1925 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1926 * array. A completely 0 filled entry terminates the table.
1928 * See register_sysctl_paths for more details.
1930 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
1932 static const struct ctl_path null_path[] = { {} };
1934 return register_sysctl_paths(null_path, table);
1938 * unregister_sysctl_table - unregister a sysctl table hierarchy
1939 * @header: the header returned from register_sysctl_table
1941 * Unregisters the sysctl table and all children. proc entries may not
1942 * actually be removed until they are no longer used by anyone.
1944 void unregister_sysctl_table(struct ctl_table_header * header)
1946 might_sleep();
1948 if (header == NULL)
1949 return;
1951 spin_lock(&sysctl_lock);
1952 start_unregistering(header);
1953 if (!--header->parent->count) {
1954 WARN_ON(1);
1955 kfree(header->parent);
1957 if (!--header->count)
1958 kfree(header);
1959 spin_unlock(&sysctl_lock);
1962 int sysctl_is_seen(struct ctl_table_header *p)
1964 struct ctl_table_set *set = p->set;
1965 int res;
1966 spin_lock(&sysctl_lock);
1967 if (p->unregistering)
1968 res = 0;
1969 else if (!set->is_seen)
1970 res = 1;
1971 else
1972 res = set->is_seen(set);
1973 spin_unlock(&sysctl_lock);
1974 return res;
1977 void setup_sysctl_set(struct ctl_table_set *p,
1978 struct ctl_table_set *parent,
1979 int (*is_seen)(struct ctl_table_set *))
1981 INIT_LIST_HEAD(&p->list);
1982 p->parent = parent ? parent : &sysctl_table_root.default_set;
1983 p->is_seen = is_seen;
1986 #else /* !CONFIG_SYSCTL */
1987 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
1989 return NULL;
1992 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1993 struct ctl_table *table)
1995 return NULL;
1998 void unregister_sysctl_table(struct ctl_table_header * table)
2002 void setup_sysctl_set(struct ctl_table_set *p,
2003 struct ctl_table_set *parent,
2004 int (*is_seen)(struct ctl_table_set *))
2008 void sysctl_head_put(struct ctl_table_header *head)
2012 #endif /* CONFIG_SYSCTL */
2015 * /proc/sys support
2018 #ifdef CONFIG_PROC_SYSCTL
2020 static int _proc_do_string(void* data, int maxlen, int write,
2021 void __user *buffer,
2022 size_t *lenp, loff_t *ppos)
2024 size_t len;
2025 char __user *p;
2026 char c;
2028 if (!data || !maxlen || !*lenp) {
2029 *lenp = 0;
2030 return 0;
2033 if (write) {
2034 len = 0;
2035 p = buffer;
2036 while (len < *lenp) {
2037 if (get_user(c, p++))
2038 return -EFAULT;
2039 if (c == 0 || c == '\n')
2040 break;
2041 len++;
2043 if (len >= maxlen)
2044 len = maxlen-1;
2045 if(copy_from_user(data, buffer, len))
2046 return -EFAULT;
2047 ((char *) data)[len] = 0;
2048 *ppos += *lenp;
2049 } else {
2050 len = strlen(data);
2051 if (len > maxlen)
2052 len = maxlen;
2054 if (*ppos > len) {
2055 *lenp = 0;
2056 return 0;
2059 data += *ppos;
2060 len -= *ppos;
2062 if (len > *lenp)
2063 len = *lenp;
2064 if (len)
2065 if(copy_to_user(buffer, data, len))
2066 return -EFAULT;
2067 if (len < *lenp) {
2068 if(put_user('\n', ((char __user *) buffer) + len))
2069 return -EFAULT;
2070 len++;
2072 *lenp = len;
2073 *ppos += len;
2075 return 0;
2079 * proc_dostring - read a string sysctl
2080 * @table: the sysctl table
2081 * @write: %TRUE if this is a write to the sysctl file
2082 * @buffer: the user buffer
2083 * @lenp: the size of the user buffer
2084 * @ppos: file position
2086 * Reads/writes a string from/to the user buffer. If the kernel
2087 * buffer provided is not large enough to hold the string, the
2088 * string is truncated. The copied string is %NULL-terminated.
2089 * If the string is being read by the user process, it is copied
2090 * and a newline '\n' is added. It is truncated if the buffer is
2091 * not large enough.
2093 * Returns 0 on success.
2095 int proc_dostring(struct ctl_table *table, int write,
2096 void __user *buffer, size_t *lenp, loff_t *ppos)
2098 return _proc_do_string(table->data, table->maxlen, write,
2099 buffer, lenp, ppos);
2102 static size_t proc_skip_spaces(char **buf)
2104 size_t ret;
2105 char *tmp = skip_spaces(*buf);
2106 ret = tmp - *buf;
2107 *buf = tmp;
2108 return ret;
2111 static void proc_skip_char(char **buf, size_t *size, const char v)
2113 while (*size) {
2114 if (**buf != v)
2115 break;
2116 (*size)--;
2117 (*buf)++;
2121 #define TMPBUFLEN 22
2123 * proc_get_long - reads an ASCII formatted integer from a user buffer
2125 * @buf: a kernel buffer
2126 * @size: size of the kernel buffer
2127 * @val: this is where the number will be stored
2128 * @neg: set to %TRUE if number is negative
2129 * @perm_tr: a vector which contains the allowed trailers
2130 * @perm_tr_len: size of the perm_tr vector
2131 * @tr: pointer to store the trailer character
2133 * In case of success %0 is returned and @buf and @size are updated with
2134 * the amount of bytes read. If @tr is non-NULL and a trailing
2135 * character exists (size is non-zero after returning from this
2136 * function), @tr is updated with the trailing character.
2138 static int proc_get_long(char **buf, size_t *size,
2139 unsigned long *val, bool *neg,
2140 const char *perm_tr, unsigned perm_tr_len, char *tr)
2142 int len;
2143 char *p, tmp[TMPBUFLEN];
2145 if (!*size)
2146 return -EINVAL;
2148 len = *size;
2149 if (len > TMPBUFLEN - 1)
2150 len = TMPBUFLEN - 1;
2152 memcpy(tmp, *buf, len);
2154 tmp[len] = 0;
2155 p = tmp;
2156 if (*p == '-' && *size > 1) {
2157 *neg = true;
2158 p++;
2159 } else
2160 *neg = false;
2161 if (!isdigit(*p))
2162 return -EINVAL;
2164 *val = simple_strtoul(p, &p, 0);
2166 len = p - tmp;
2168 /* We don't know if the next char is whitespace thus we may accept
2169 * invalid integers (e.g. 1234...a) or two integers instead of one
2170 * (e.g. 123...1). So lets not allow such large numbers. */
2171 if (len == TMPBUFLEN - 1)
2172 return -EINVAL;
2174 if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
2175 return -EINVAL;
2177 if (tr && (len < *size))
2178 *tr = *p;
2180 *buf += len;
2181 *size -= len;
2183 return 0;
2187 * proc_put_long - converts an integer to a decimal ASCII formatted string
2189 * @buf: the user buffer
2190 * @size: the size of the user buffer
2191 * @val: the integer to be converted
2192 * @neg: sign of the number, %TRUE for negative
2194 * In case of success %0 is returned and @buf and @size are updated with
2195 * the amount of bytes written.
2197 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2198 bool neg)
2200 int len;
2201 char tmp[TMPBUFLEN], *p = tmp;
2203 sprintf(p, "%s%lu", neg ? "-" : "", val);
2204 len = strlen(tmp);
2205 if (len > *size)
2206 len = *size;
2207 if (copy_to_user(*buf, tmp, len))
2208 return -EFAULT;
2209 *size -= len;
2210 *buf += len;
2211 return 0;
2213 #undef TMPBUFLEN
2215 static int proc_put_char(void __user **buf, size_t *size, char c)
2217 if (*size) {
2218 char __user **buffer = (char __user **)buf;
2219 if (put_user(c, *buffer))
2220 return -EFAULT;
2221 (*size)--, (*buffer)++;
2222 *buf = *buffer;
2224 return 0;
2227 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
2228 int *valp,
2229 int write, void *data)
2231 if (write) {
2232 *valp = *negp ? -*lvalp : *lvalp;
2233 } else {
2234 int val = *valp;
2235 if (val < 0) {
2236 *negp = true;
2237 *lvalp = (unsigned long)-val;
2238 } else {
2239 *negp = false;
2240 *lvalp = (unsigned long)val;
2243 return 0;
2246 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2248 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2249 int write, void __user *buffer,
2250 size_t *lenp, loff_t *ppos,
2251 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2252 int write, void *data),
2253 void *data)
2255 int *i, vleft, first = 1, err = 0;
2256 unsigned long page = 0;
2257 size_t left;
2258 char *kbuf;
2260 if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2261 *lenp = 0;
2262 return 0;
2265 i = (int *) tbl_data;
2266 vleft = table->maxlen / sizeof(*i);
2267 left = *lenp;
2269 if (!conv)
2270 conv = do_proc_dointvec_conv;
2272 if (write) {
2273 if (left > PAGE_SIZE - 1)
2274 left = PAGE_SIZE - 1;
2275 page = __get_free_page(GFP_TEMPORARY);
2276 kbuf = (char *) page;
2277 if (!kbuf)
2278 return -ENOMEM;
2279 if (copy_from_user(kbuf, buffer, left)) {
2280 err = -EFAULT;
2281 goto free;
2283 kbuf[left] = 0;
2286 for (; left && vleft--; i++, first=0) {
2287 unsigned long lval;
2288 bool neg;
2290 if (write) {
2291 left -= proc_skip_spaces(&kbuf);
2293 if (!left)
2294 break;
2295 err = proc_get_long(&kbuf, &left, &lval, &neg,
2296 proc_wspace_sep,
2297 sizeof(proc_wspace_sep), NULL);
2298 if (err)
2299 break;
2300 if (conv(&neg, &lval, i, 1, data)) {
2301 err = -EINVAL;
2302 break;
2304 } else {
2305 if (conv(&neg, &lval, i, 0, data)) {
2306 err = -EINVAL;
2307 break;
2309 if (!first)
2310 err = proc_put_char(&buffer, &left, '\t');
2311 if (err)
2312 break;
2313 err = proc_put_long(&buffer, &left, lval, neg);
2314 if (err)
2315 break;
2319 if (!write && !first && left && !err)
2320 err = proc_put_char(&buffer, &left, '\n');
2321 if (write && !err && left)
2322 left -= proc_skip_spaces(&kbuf);
2323 free:
2324 if (write) {
2325 free_page(page);
2326 if (first)
2327 return err ? : -EINVAL;
2329 *lenp -= left;
2330 *ppos += *lenp;
2331 return err;
2334 static int do_proc_dointvec(struct ctl_table *table, int write,
2335 void __user *buffer, size_t *lenp, loff_t *ppos,
2336 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2337 int write, void *data),
2338 void *data)
2340 return __do_proc_dointvec(table->data, table, write,
2341 buffer, lenp, ppos, conv, data);
2345 * proc_dointvec - read a vector of integers
2346 * @table: the sysctl table
2347 * @write: %TRUE if this is a write to the sysctl file
2348 * @buffer: the user buffer
2349 * @lenp: the size of the user buffer
2350 * @ppos: file position
2352 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2353 * values from/to the user buffer, treated as an ASCII string.
2355 * Returns 0 on success.
2357 int proc_dointvec(struct ctl_table *table, int write,
2358 void __user *buffer, size_t *lenp, loff_t *ppos)
2360 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2361 NULL,NULL);
2365 * Taint values can only be increased
2366 * This means we can safely use a temporary.
2368 static int proc_taint(struct ctl_table *table, int write,
2369 void __user *buffer, size_t *lenp, loff_t *ppos)
2371 struct ctl_table t;
2372 unsigned long tmptaint = get_taint();
2373 int err;
2375 if (write && !capable(CAP_SYS_ADMIN))
2376 return -EPERM;
2378 t = *table;
2379 t.data = &tmptaint;
2380 err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2381 if (err < 0)
2382 return err;
2384 if (write) {
2386 * Poor man's atomic or. Not worth adding a primitive
2387 * to everyone's atomic.h for this
2389 int i;
2390 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2391 if ((tmptaint >> i) & 1)
2392 add_taint(i);
2396 return err;
2399 struct do_proc_dointvec_minmax_conv_param {
2400 int *min;
2401 int *max;
2404 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2405 int *valp,
2406 int write, void *data)
2408 struct do_proc_dointvec_minmax_conv_param *param = data;
2409 if (write) {
2410 int val = *negp ? -*lvalp : *lvalp;
2411 if ((param->min && *param->min > val) ||
2412 (param->max && *param->max < val))
2413 return -EINVAL;
2414 *valp = val;
2415 } else {
2416 int val = *valp;
2417 if (val < 0) {
2418 *negp = true;
2419 *lvalp = (unsigned long)-val;
2420 } else {
2421 *negp = false;
2422 *lvalp = (unsigned long)val;
2425 return 0;
2429 * proc_dointvec_minmax - read a vector of integers with min/max values
2430 * @table: the sysctl table
2431 * @write: %TRUE if this is a write to the sysctl file
2432 * @buffer: the user buffer
2433 * @lenp: the size of the user buffer
2434 * @ppos: file position
2436 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2437 * values from/to the user buffer, treated as an ASCII string.
2439 * This routine will ensure the values are within the range specified by
2440 * table->extra1 (min) and table->extra2 (max).
2442 * Returns 0 on success.
2444 int proc_dointvec_minmax(struct ctl_table *table, int write,
2445 void __user *buffer, size_t *lenp, loff_t *ppos)
2447 struct do_proc_dointvec_minmax_conv_param param = {
2448 .min = (int *) table->extra1,
2449 .max = (int *) table->extra2,
2451 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2452 do_proc_dointvec_minmax_conv, &param);
2455 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2456 void __user *buffer,
2457 size_t *lenp, loff_t *ppos,
2458 unsigned long convmul,
2459 unsigned long convdiv)
2461 unsigned long *i, *min, *max;
2462 int vleft, first = 1, err = 0;
2463 unsigned long page = 0;
2464 size_t left;
2465 char *kbuf;
2467 if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2468 *lenp = 0;
2469 return 0;
2472 i = (unsigned long *) data;
2473 min = (unsigned long *) table->extra1;
2474 max = (unsigned long *) table->extra2;
2475 vleft = table->maxlen / sizeof(unsigned long);
2476 left = *lenp;
2478 if (write) {
2479 if (left > PAGE_SIZE - 1)
2480 left = PAGE_SIZE - 1;
2481 page = __get_free_page(GFP_TEMPORARY);
2482 kbuf = (char *) page;
2483 if (!kbuf)
2484 return -ENOMEM;
2485 if (copy_from_user(kbuf, buffer, left)) {
2486 err = -EFAULT;
2487 goto free;
2489 kbuf[left] = 0;
2492 for (; left && vleft--; i++, min++, max++, first=0) {
2493 unsigned long val;
2495 if (write) {
2496 bool neg;
2498 left -= proc_skip_spaces(&kbuf);
2500 err = proc_get_long(&kbuf, &left, &val, &neg,
2501 proc_wspace_sep,
2502 sizeof(proc_wspace_sep), NULL);
2503 if (err)
2504 break;
2505 if (neg)
2506 continue;
2507 if ((min && val < *min) || (max && val > *max))
2508 continue;
2509 *i = val;
2510 } else {
2511 val = convdiv * (*i) / convmul;
2512 if (!first)
2513 err = proc_put_char(&buffer, &left, '\t');
2514 err = proc_put_long(&buffer, &left, val, false);
2515 if (err)
2516 break;
2520 if (!write && !first && left && !err)
2521 err = proc_put_char(&buffer, &left, '\n');
2522 if (write && !err)
2523 left -= proc_skip_spaces(&kbuf);
2524 free:
2525 if (write) {
2526 free_page(page);
2527 if (first)
2528 return err ? : -EINVAL;
2530 *lenp -= left;
2531 *ppos += *lenp;
2532 return err;
2535 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2536 void __user *buffer,
2537 size_t *lenp, loff_t *ppos,
2538 unsigned long convmul,
2539 unsigned long convdiv)
2541 return __do_proc_doulongvec_minmax(table->data, table, write,
2542 buffer, lenp, ppos, convmul, convdiv);
2546 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2547 * @table: the sysctl table
2548 * @write: %TRUE if this is a write to the sysctl file
2549 * @buffer: the user buffer
2550 * @lenp: the size of the user buffer
2551 * @ppos: file position
2553 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2554 * values from/to the user buffer, treated as an ASCII string.
2556 * This routine will ensure the values are within the range specified by
2557 * table->extra1 (min) and table->extra2 (max).
2559 * Returns 0 on success.
2561 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2562 void __user *buffer, size_t *lenp, loff_t *ppos)
2564 return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2568 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2569 * @table: the sysctl table
2570 * @write: %TRUE if this is a write to the sysctl file
2571 * @buffer: the user buffer
2572 * @lenp: the size of the user buffer
2573 * @ppos: file position
2575 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2576 * values from/to the user buffer, treated as an ASCII string. The values
2577 * are treated as milliseconds, and converted to jiffies when they are stored.
2579 * This routine will ensure the values are within the range specified by
2580 * table->extra1 (min) and table->extra2 (max).
2582 * Returns 0 on success.
2584 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2585 void __user *buffer,
2586 size_t *lenp, loff_t *ppos)
2588 return do_proc_doulongvec_minmax(table, write, buffer,
2589 lenp, ppos, HZ, 1000l);
2593 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2594 int *valp,
2595 int write, void *data)
2597 if (write) {
2598 if (*lvalp > LONG_MAX / HZ)
2599 return 1;
2600 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2601 } else {
2602 int val = *valp;
2603 unsigned long lval;
2604 if (val < 0) {
2605 *negp = true;
2606 lval = (unsigned long)-val;
2607 } else {
2608 *negp = false;
2609 lval = (unsigned long)val;
2611 *lvalp = lval / HZ;
2613 return 0;
2616 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
2617 int *valp,
2618 int write, void *data)
2620 if (write) {
2621 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2622 return 1;
2623 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2624 } else {
2625 int val = *valp;
2626 unsigned long lval;
2627 if (val < 0) {
2628 *negp = true;
2629 lval = (unsigned long)-val;
2630 } else {
2631 *negp = false;
2632 lval = (unsigned long)val;
2634 *lvalp = jiffies_to_clock_t(lval);
2636 return 0;
2639 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
2640 int *valp,
2641 int write, void *data)
2643 if (write) {
2644 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2645 } else {
2646 int val = *valp;
2647 unsigned long lval;
2648 if (val < 0) {
2649 *negp = true;
2650 lval = (unsigned long)-val;
2651 } else {
2652 *negp = false;
2653 lval = (unsigned long)val;
2655 *lvalp = jiffies_to_msecs(lval);
2657 return 0;
2661 * proc_dointvec_jiffies - read a vector of integers as seconds
2662 * @table: the sysctl table
2663 * @write: %TRUE if this is a write to the sysctl file
2664 * @buffer: the user buffer
2665 * @lenp: the size of the user buffer
2666 * @ppos: file position
2668 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2669 * values from/to the user buffer, treated as an ASCII string.
2670 * The values read are assumed to be in seconds, and are converted into
2671 * jiffies.
2673 * Returns 0 on success.
2675 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2676 void __user *buffer, size_t *lenp, loff_t *ppos)
2678 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2679 do_proc_dointvec_jiffies_conv,NULL);
2683 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2684 * @table: the sysctl table
2685 * @write: %TRUE if this is a write to the sysctl file
2686 * @buffer: the user buffer
2687 * @lenp: the size of the user buffer
2688 * @ppos: pointer to the file position
2690 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2691 * values from/to the user buffer, treated as an ASCII string.
2692 * The values read are assumed to be in 1/USER_HZ seconds, and
2693 * are converted into jiffies.
2695 * Returns 0 on success.
2697 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2698 void __user *buffer, size_t *lenp, loff_t *ppos)
2700 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2701 do_proc_dointvec_userhz_jiffies_conv,NULL);
2705 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2706 * @table: the sysctl table
2707 * @write: %TRUE if this is a write to the sysctl file
2708 * @buffer: the user buffer
2709 * @lenp: the size of the user buffer
2710 * @ppos: file position
2711 * @ppos: the current position in the file
2713 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2714 * values from/to the user buffer, treated as an ASCII string.
2715 * The values read are assumed to be in 1/1000 seconds, and
2716 * are converted into jiffies.
2718 * Returns 0 on success.
2720 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2721 void __user *buffer, size_t *lenp, loff_t *ppos)
2723 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2724 do_proc_dointvec_ms_jiffies_conv, NULL);
2727 static int proc_do_cad_pid(struct ctl_table *table, int write,
2728 void __user *buffer, size_t *lenp, loff_t *ppos)
2730 struct pid *new_pid;
2731 pid_t tmp;
2732 int r;
2734 tmp = pid_vnr(cad_pid);
2736 r = __do_proc_dointvec(&tmp, table, write, buffer,
2737 lenp, ppos, NULL, NULL);
2738 if (r || !write)
2739 return r;
2741 new_pid = find_get_pid(tmp);
2742 if (!new_pid)
2743 return -ESRCH;
2745 put_pid(xchg(&cad_pid, new_pid));
2746 return 0;
2750 * proc_do_large_bitmap - read/write from/to a large bitmap
2751 * @table: the sysctl table
2752 * @write: %TRUE if this is a write to the sysctl file
2753 * @buffer: the user buffer
2754 * @lenp: the size of the user buffer
2755 * @ppos: file position
2757 * The bitmap is stored at table->data and the bitmap length (in bits)
2758 * in table->maxlen.
2760 * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2761 * large bitmaps may be represented in a compact manner. Writing into
2762 * the file will clear the bitmap then update it with the given input.
2764 * Returns 0 on success.
2766 int proc_do_large_bitmap(struct ctl_table *table, int write,
2767 void __user *buffer, size_t *lenp, loff_t *ppos)
2769 int err = 0;
2770 bool first = 1;
2771 size_t left = *lenp;
2772 unsigned long bitmap_len = table->maxlen;
2773 unsigned long *bitmap = (unsigned long *) table->data;
2774 unsigned long *tmp_bitmap = NULL;
2775 char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
2777 if (!bitmap_len || !left || (*ppos && !write)) {
2778 *lenp = 0;
2779 return 0;
2782 if (write) {
2783 unsigned long page = 0;
2784 char *kbuf;
2786 if (left > PAGE_SIZE - 1)
2787 left = PAGE_SIZE - 1;
2789 page = __get_free_page(GFP_TEMPORARY);
2790 kbuf = (char *) page;
2791 if (!kbuf)
2792 return -ENOMEM;
2793 if (copy_from_user(kbuf, buffer, left)) {
2794 free_page(page);
2795 return -EFAULT;
2797 kbuf[left] = 0;
2799 tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
2800 GFP_KERNEL);
2801 if (!tmp_bitmap) {
2802 free_page(page);
2803 return -ENOMEM;
2805 proc_skip_char(&kbuf, &left, '\n');
2806 while (!err && left) {
2807 unsigned long val_a, val_b;
2808 bool neg;
2810 err = proc_get_long(&kbuf, &left, &val_a, &neg, tr_a,
2811 sizeof(tr_a), &c);
2812 if (err)
2813 break;
2814 if (val_a >= bitmap_len || neg) {
2815 err = -EINVAL;
2816 break;
2819 val_b = val_a;
2820 if (left) {
2821 kbuf++;
2822 left--;
2825 if (c == '-') {
2826 err = proc_get_long(&kbuf, &left, &val_b,
2827 &neg, tr_b, sizeof(tr_b),
2828 &c);
2829 if (err)
2830 break;
2831 if (val_b >= bitmap_len || neg ||
2832 val_a > val_b) {
2833 err = -EINVAL;
2834 break;
2836 if (left) {
2837 kbuf++;
2838 left--;
2842 while (val_a <= val_b)
2843 set_bit(val_a++, tmp_bitmap);
2845 first = 0;
2846 proc_skip_char(&kbuf, &left, '\n');
2848 free_page(page);
2849 } else {
2850 unsigned long bit_a, bit_b = 0;
2852 while (left) {
2853 bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
2854 if (bit_a >= bitmap_len)
2855 break;
2856 bit_b = find_next_zero_bit(bitmap, bitmap_len,
2857 bit_a + 1) - 1;
2859 if (!first) {
2860 err = proc_put_char(&buffer, &left, ',');
2861 if (err)
2862 break;
2864 err = proc_put_long(&buffer, &left, bit_a, false);
2865 if (err)
2866 break;
2867 if (bit_a != bit_b) {
2868 err = proc_put_char(&buffer, &left, '-');
2869 if (err)
2870 break;
2871 err = proc_put_long(&buffer, &left, bit_b, false);
2872 if (err)
2873 break;
2876 first = 0; bit_b++;
2878 if (!err)
2879 err = proc_put_char(&buffer, &left, '\n');
2882 if (!err) {
2883 if (write) {
2884 if (*ppos)
2885 bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
2886 else
2887 memcpy(bitmap, tmp_bitmap,
2888 BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long));
2890 kfree(tmp_bitmap);
2891 *lenp -= left;
2892 *ppos += *lenp;
2893 return 0;
2894 } else {
2895 kfree(tmp_bitmap);
2896 return err;
2900 #else /* CONFIG_PROC_FS */
2902 int proc_dostring(struct ctl_table *table, int write,
2903 void __user *buffer, size_t *lenp, loff_t *ppos)
2905 return -ENOSYS;
2908 int proc_dointvec(struct ctl_table *table, int write,
2909 void __user *buffer, size_t *lenp, loff_t *ppos)
2911 return -ENOSYS;
2914 int proc_dointvec_minmax(struct ctl_table *table, int write,
2915 void __user *buffer, size_t *lenp, loff_t *ppos)
2917 return -ENOSYS;
2920 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2921 void __user *buffer, size_t *lenp, loff_t *ppos)
2923 return -ENOSYS;
2926 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2927 void __user *buffer, size_t *lenp, loff_t *ppos)
2929 return -ENOSYS;
2932 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2933 void __user *buffer, size_t *lenp, loff_t *ppos)
2935 return -ENOSYS;
2938 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2939 void __user *buffer, size_t *lenp, loff_t *ppos)
2941 return -ENOSYS;
2944 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2945 void __user *buffer,
2946 size_t *lenp, loff_t *ppos)
2948 return -ENOSYS;
2952 #endif /* CONFIG_PROC_FS */
2955 * No sense putting this after each symbol definition, twice,
2956 * exception granted :-)
2958 EXPORT_SYMBOL(proc_dointvec);
2959 EXPORT_SYMBOL(proc_dointvec_jiffies);
2960 EXPORT_SYMBOL(proc_dointvec_minmax);
2961 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2962 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2963 EXPORT_SYMBOL(proc_dostring);
2964 EXPORT_SYMBOL(proc_doulongvec_minmax);
2965 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2966 EXPORT_SYMBOL(register_sysctl_table);
2967 EXPORT_SYMBOL(register_sysctl_paths);
2968 EXPORT_SYMBOL(unregister_sysctl_table);