USB: ftdi_sio: Add PID for accesio products
[linux/fpc-iii.git] / kernel / sysctl.c
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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/slow-work.h>
54 #include <linux/perf_event.h>
55 #include <linux/kprobes.h>
56 #include <linux/pipe_fs_i.h>
58 #include <asm/uaccess.h>
59 #include <asm/processor.h>
61 #ifdef CONFIG_X86
62 #include <asm/nmi.h>
63 #include <asm/stacktrace.h>
64 #include <asm/io.h>
65 #endif
66 #ifdef CONFIG_BSD_PROCESS_ACCT
67 #include <linux/acct.h>
68 #endif
69 #ifdef CONFIG_RT_MUTEXES
70 #include <linux/rtmutex.h>
71 #endif
72 #if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT)
73 #include <linux/lockdep.h>
74 #endif
75 #ifdef CONFIG_CHR_DEV_SG
76 #include <scsi/sg.h>
77 #endif
80 #if defined(CONFIG_SYSCTL)
82 /* External variables not in a header file. */
83 extern int sysctl_overcommit_memory;
84 extern int sysctl_overcommit_ratio;
85 extern int sysctl_panic_on_oom;
86 extern int sysctl_oom_kill_allocating_task;
87 extern int sysctl_oom_dump_tasks;
88 extern int max_threads;
89 extern int core_uses_pid;
90 extern int suid_dumpable;
91 extern char core_pattern[];
92 extern unsigned int core_pipe_limit;
93 extern int pid_max;
94 extern int min_free_kbytes;
95 extern int pid_max_min, pid_max_max;
96 extern int sysctl_drop_caches;
97 extern int percpu_pagelist_fraction;
98 extern int compat_log;
99 extern int latencytop_enabled;
100 extern int sysctl_nr_open_min, sysctl_nr_open_max;
101 #ifndef CONFIG_MMU
102 extern int sysctl_nr_trim_pages;
103 #endif
104 #ifdef CONFIG_BLOCK
105 extern int blk_iopoll_enabled;
106 #endif
108 /* Constants used for minimum and maximum */
109 #ifdef CONFIG_DETECT_SOFTLOCKUP
110 static int sixty = 60;
111 static int neg_one = -1;
112 #endif
114 static int zero;
115 static int __maybe_unused one = 1;
116 static int __maybe_unused two = 2;
117 static unsigned long one_ul = 1;
118 static int one_hundred = 100;
119 #ifdef CONFIG_PRINTK
120 static int ten_thousand = 10000;
121 #endif
123 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
124 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
126 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
127 static int maxolduid = 65535;
128 static int minolduid;
129 static int min_percpu_pagelist_fract = 8;
131 static int ngroups_max = NGROUPS_MAX;
133 #ifdef CONFIG_SPARC
134 #include <asm/system.h>
135 #endif
137 #ifdef CONFIG_SPARC64
138 extern int sysctl_tsb_ratio;
139 #endif
141 #ifdef __hppa__
142 extern int pwrsw_enabled;
143 extern int unaligned_enabled;
144 #endif
146 #ifdef CONFIG_S390
147 #ifdef CONFIG_MATHEMU
148 extern int sysctl_ieee_emulation_warnings;
149 #endif
150 extern int sysctl_userprocess_debug;
151 extern int spin_retry;
152 #endif
154 #ifdef CONFIG_IA64
155 extern int no_unaligned_warning;
156 extern int unaligned_dump_stack;
157 #endif
159 extern struct ratelimit_state printk_ratelimit_state;
161 #ifdef CONFIG_PROC_SYSCTL
162 static int proc_do_cad_pid(struct ctl_table *table, int write,
163 void __user *buffer, size_t *lenp, loff_t *ppos);
164 static int proc_taint(struct ctl_table *table, int write,
165 void __user *buffer, size_t *lenp, loff_t *ppos);
166 #endif
168 #ifdef CONFIG_MAGIC_SYSRQ
169 static int __sysrq_enabled; /* Note: sysrq code ises it's own private copy */
171 static int sysrq_sysctl_handler(ctl_table *table, int write,
172 void __user *buffer, size_t *lenp,
173 loff_t *ppos)
175 int error;
177 error = proc_dointvec(table, write, buffer, lenp, ppos);
178 if (error)
179 return error;
181 if (write)
182 sysrq_toggle_support(__sysrq_enabled);
184 return 0;
187 #endif
189 static struct ctl_table root_table[];
190 static struct ctl_table_root sysctl_table_root;
191 static struct ctl_table_header root_table_header = {
192 .count = 1,
193 .ctl_table = root_table,
194 .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
195 .root = &sysctl_table_root,
196 .set = &sysctl_table_root.default_set,
198 static struct ctl_table_root sysctl_table_root = {
199 .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
200 .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
203 static struct ctl_table kern_table[];
204 static struct ctl_table vm_table[];
205 static struct ctl_table fs_table[];
206 static struct ctl_table debug_table[];
207 static struct ctl_table dev_table[];
208 extern struct ctl_table random_table[];
209 #ifdef CONFIG_INOTIFY_USER
210 extern struct ctl_table inotify_table[];
211 #endif
212 #ifdef CONFIG_EPOLL
213 extern struct ctl_table epoll_table[];
214 #endif
216 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
217 int sysctl_legacy_va_layout;
218 #endif
220 /* The default sysctl tables: */
222 static struct ctl_table root_table[] = {
224 .procname = "kernel",
225 .mode = 0555,
226 .child = kern_table,
229 .procname = "vm",
230 .mode = 0555,
231 .child = vm_table,
234 .procname = "fs",
235 .mode = 0555,
236 .child = fs_table,
239 .procname = "debug",
240 .mode = 0555,
241 .child = debug_table,
244 .procname = "dev",
245 .mode = 0555,
246 .child = dev_table,
249 * NOTE: do not add new entries to this table unless you have read
250 * Documentation/sysctl/ctl_unnumbered.txt
255 #ifdef CONFIG_SCHED_DEBUG
256 static int min_sched_granularity_ns = 100000; /* 100 usecs */
257 static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
258 static int min_wakeup_granularity_ns; /* 0 usecs */
259 static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
260 static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
261 static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
262 static int min_sched_shares_ratelimit = 100000; /* 100 usec */
263 static int max_sched_shares_ratelimit = NSEC_PER_SEC; /* 1 second */
264 #endif
266 #ifdef CONFIG_COMPACTION
267 static int min_extfrag_threshold;
268 static int max_extfrag_threshold = 1000;
269 #endif
271 static struct ctl_table kern_table[] = {
273 .procname = "sched_child_runs_first",
274 .data = &sysctl_sched_child_runs_first,
275 .maxlen = sizeof(unsigned int),
276 .mode = 0644,
277 .proc_handler = proc_dointvec,
279 #ifdef CONFIG_SCHED_DEBUG
281 .procname = "sched_min_granularity_ns",
282 .data = &sysctl_sched_min_granularity,
283 .maxlen = sizeof(unsigned int),
284 .mode = 0644,
285 .proc_handler = sched_proc_update_handler,
286 .extra1 = &min_sched_granularity_ns,
287 .extra2 = &max_sched_granularity_ns,
290 .procname = "sched_latency_ns",
291 .data = &sysctl_sched_latency,
292 .maxlen = sizeof(unsigned int),
293 .mode = 0644,
294 .proc_handler = sched_proc_update_handler,
295 .extra1 = &min_sched_granularity_ns,
296 .extra2 = &max_sched_granularity_ns,
299 .procname = "sched_wakeup_granularity_ns",
300 .data = &sysctl_sched_wakeup_granularity,
301 .maxlen = sizeof(unsigned int),
302 .mode = 0644,
303 .proc_handler = sched_proc_update_handler,
304 .extra1 = &min_wakeup_granularity_ns,
305 .extra2 = &max_wakeup_granularity_ns,
308 .procname = "sched_shares_ratelimit",
309 .data = &sysctl_sched_shares_ratelimit,
310 .maxlen = sizeof(unsigned int),
311 .mode = 0644,
312 .proc_handler = sched_proc_update_handler,
313 .extra1 = &min_sched_shares_ratelimit,
314 .extra2 = &max_sched_shares_ratelimit,
317 .procname = "sched_tunable_scaling",
318 .data = &sysctl_sched_tunable_scaling,
319 .maxlen = sizeof(enum sched_tunable_scaling),
320 .mode = 0644,
321 .proc_handler = sched_proc_update_handler,
322 .extra1 = &min_sched_tunable_scaling,
323 .extra2 = &max_sched_tunable_scaling,
326 .procname = "sched_shares_thresh",
327 .data = &sysctl_sched_shares_thresh,
328 .maxlen = sizeof(unsigned int),
329 .mode = 0644,
330 .proc_handler = proc_dointvec_minmax,
331 .extra1 = &zero,
334 .procname = "sched_migration_cost",
335 .data = &sysctl_sched_migration_cost,
336 .maxlen = sizeof(unsigned int),
337 .mode = 0644,
338 .proc_handler = proc_dointvec,
341 .procname = "sched_nr_migrate",
342 .data = &sysctl_sched_nr_migrate,
343 .maxlen = sizeof(unsigned int),
344 .mode = 0644,
345 .proc_handler = proc_dointvec,
348 .procname = "sched_time_avg",
349 .data = &sysctl_sched_time_avg,
350 .maxlen = sizeof(unsigned int),
351 .mode = 0644,
352 .proc_handler = proc_dointvec,
355 .procname = "timer_migration",
356 .data = &sysctl_timer_migration,
357 .maxlen = sizeof(unsigned int),
358 .mode = 0644,
359 .proc_handler = proc_dointvec_minmax,
360 .extra1 = &zero,
361 .extra2 = &one,
363 #endif
365 .procname = "sched_rt_period_us",
366 .data = &sysctl_sched_rt_period,
367 .maxlen = sizeof(unsigned int),
368 .mode = 0644,
369 .proc_handler = sched_rt_handler,
372 .procname = "sched_rt_runtime_us",
373 .data = &sysctl_sched_rt_runtime,
374 .maxlen = sizeof(int),
375 .mode = 0644,
376 .proc_handler = sched_rt_handler,
379 .procname = "sched_compat_yield",
380 .data = &sysctl_sched_compat_yield,
381 .maxlen = sizeof(unsigned int),
382 .mode = 0644,
383 .proc_handler = proc_dointvec,
385 #ifdef CONFIG_PROVE_LOCKING
387 .procname = "prove_locking",
388 .data = &prove_locking,
389 .maxlen = sizeof(int),
390 .mode = 0644,
391 .proc_handler = proc_dointvec,
393 #endif
394 #ifdef CONFIG_LOCK_STAT
396 .procname = "lock_stat",
397 .data = &lock_stat,
398 .maxlen = sizeof(int),
399 .mode = 0644,
400 .proc_handler = proc_dointvec,
402 #endif
404 .procname = "panic",
405 .data = &panic_timeout,
406 .maxlen = sizeof(int),
407 .mode = 0644,
408 .proc_handler = proc_dointvec,
411 .procname = "core_uses_pid",
412 .data = &core_uses_pid,
413 .maxlen = sizeof(int),
414 .mode = 0644,
415 .proc_handler = proc_dointvec,
418 .procname = "core_pattern",
419 .data = core_pattern,
420 .maxlen = CORENAME_MAX_SIZE,
421 .mode = 0644,
422 .proc_handler = proc_dostring,
425 .procname = "core_pipe_limit",
426 .data = &core_pipe_limit,
427 .maxlen = sizeof(unsigned int),
428 .mode = 0644,
429 .proc_handler = proc_dointvec,
431 #ifdef CONFIG_PROC_SYSCTL
433 .procname = "tainted",
434 .maxlen = sizeof(long),
435 .mode = 0644,
436 .proc_handler = proc_taint,
438 #endif
439 #ifdef CONFIG_LATENCYTOP
441 .procname = "latencytop",
442 .data = &latencytop_enabled,
443 .maxlen = sizeof(int),
444 .mode = 0644,
445 .proc_handler = proc_dointvec,
447 #endif
448 #ifdef CONFIG_BLK_DEV_INITRD
450 .procname = "real-root-dev",
451 .data = &real_root_dev,
452 .maxlen = sizeof(int),
453 .mode = 0644,
454 .proc_handler = proc_dointvec,
456 #endif
458 .procname = "print-fatal-signals",
459 .data = &print_fatal_signals,
460 .maxlen = sizeof(int),
461 .mode = 0644,
462 .proc_handler = proc_dointvec,
464 #ifdef CONFIG_SPARC
466 .procname = "reboot-cmd",
467 .data = reboot_command,
468 .maxlen = 256,
469 .mode = 0644,
470 .proc_handler = proc_dostring,
473 .procname = "stop-a",
474 .data = &stop_a_enabled,
475 .maxlen = sizeof (int),
476 .mode = 0644,
477 .proc_handler = proc_dointvec,
480 .procname = "scons-poweroff",
481 .data = &scons_pwroff,
482 .maxlen = sizeof (int),
483 .mode = 0644,
484 .proc_handler = proc_dointvec,
486 #endif
487 #ifdef CONFIG_SPARC64
489 .procname = "tsb-ratio",
490 .data = &sysctl_tsb_ratio,
491 .maxlen = sizeof (int),
492 .mode = 0644,
493 .proc_handler = proc_dointvec,
495 #endif
496 #ifdef __hppa__
498 .procname = "soft-power",
499 .data = &pwrsw_enabled,
500 .maxlen = sizeof (int),
501 .mode = 0644,
502 .proc_handler = proc_dointvec,
505 .procname = "unaligned-trap",
506 .data = &unaligned_enabled,
507 .maxlen = sizeof (int),
508 .mode = 0644,
509 .proc_handler = proc_dointvec,
511 #endif
513 .procname = "ctrl-alt-del",
514 .data = &C_A_D,
515 .maxlen = sizeof(int),
516 .mode = 0644,
517 .proc_handler = proc_dointvec,
519 #ifdef CONFIG_FUNCTION_TRACER
521 .procname = "ftrace_enabled",
522 .data = &ftrace_enabled,
523 .maxlen = sizeof(int),
524 .mode = 0644,
525 .proc_handler = ftrace_enable_sysctl,
527 #endif
528 #ifdef CONFIG_STACK_TRACER
530 .procname = "stack_tracer_enabled",
531 .data = &stack_tracer_enabled,
532 .maxlen = sizeof(int),
533 .mode = 0644,
534 .proc_handler = stack_trace_sysctl,
536 #endif
537 #ifdef CONFIG_TRACING
539 .procname = "ftrace_dump_on_oops",
540 .data = &ftrace_dump_on_oops,
541 .maxlen = sizeof(int),
542 .mode = 0644,
543 .proc_handler = proc_dointvec,
545 #endif
546 #ifdef CONFIG_MODULES
548 .procname = "modprobe",
549 .data = &modprobe_path,
550 .maxlen = KMOD_PATH_LEN,
551 .mode = 0644,
552 .proc_handler = proc_dostring,
555 .procname = "modules_disabled",
556 .data = &modules_disabled,
557 .maxlen = sizeof(int),
558 .mode = 0644,
559 /* only handle a transition from default "0" to "1" */
560 .proc_handler = proc_dointvec_minmax,
561 .extra1 = &one,
562 .extra2 = &one,
564 #endif
565 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
567 .procname = "hotplug",
568 .data = &uevent_helper,
569 .maxlen = UEVENT_HELPER_PATH_LEN,
570 .mode = 0644,
571 .proc_handler = proc_dostring,
573 #endif
574 #ifdef CONFIG_CHR_DEV_SG
576 .procname = "sg-big-buff",
577 .data = &sg_big_buff,
578 .maxlen = sizeof (int),
579 .mode = 0444,
580 .proc_handler = proc_dointvec,
582 #endif
583 #ifdef CONFIG_BSD_PROCESS_ACCT
585 .procname = "acct",
586 .data = &acct_parm,
587 .maxlen = 3*sizeof(int),
588 .mode = 0644,
589 .proc_handler = proc_dointvec,
591 #endif
592 #ifdef CONFIG_MAGIC_SYSRQ
594 .procname = "sysrq",
595 .data = &__sysrq_enabled,
596 .maxlen = sizeof (int),
597 .mode = 0644,
598 .proc_handler = sysrq_sysctl_handler,
600 #endif
601 #ifdef CONFIG_PROC_SYSCTL
603 .procname = "cad_pid",
604 .data = NULL,
605 .maxlen = sizeof (int),
606 .mode = 0600,
607 .proc_handler = proc_do_cad_pid,
609 #endif
611 .procname = "threads-max",
612 .data = &max_threads,
613 .maxlen = sizeof(int),
614 .mode = 0644,
615 .proc_handler = proc_dointvec,
618 .procname = "random",
619 .mode = 0555,
620 .child = random_table,
623 .procname = "overflowuid",
624 .data = &overflowuid,
625 .maxlen = sizeof(int),
626 .mode = 0644,
627 .proc_handler = proc_dointvec_minmax,
628 .extra1 = &minolduid,
629 .extra2 = &maxolduid,
632 .procname = "overflowgid",
633 .data = &overflowgid,
634 .maxlen = sizeof(int),
635 .mode = 0644,
636 .proc_handler = proc_dointvec_minmax,
637 .extra1 = &minolduid,
638 .extra2 = &maxolduid,
640 #ifdef CONFIG_S390
641 #ifdef CONFIG_MATHEMU
643 .procname = "ieee_emulation_warnings",
644 .data = &sysctl_ieee_emulation_warnings,
645 .maxlen = sizeof(int),
646 .mode = 0644,
647 .proc_handler = proc_dointvec,
649 #endif
651 .procname = "userprocess_debug",
652 .data = &show_unhandled_signals,
653 .maxlen = sizeof(int),
654 .mode = 0644,
655 .proc_handler = proc_dointvec,
657 #endif
659 .procname = "pid_max",
660 .data = &pid_max,
661 .maxlen = sizeof (int),
662 .mode = 0644,
663 .proc_handler = proc_dointvec_minmax,
664 .extra1 = &pid_max_min,
665 .extra2 = &pid_max_max,
668 .procname = "panic_on_oops",
669 .data = &panic_on_oops,
670 .maxlen = sizeof(int),
671 .mode = 0644,
672 .proc_handler = proc_dointvec,
674 #if defined CONFIG_PRINTK
676 .procname = "printk",
677 .data = &console_loglevel,
678 .maxlen = 4*sizeof(int),
679 .mode = 0644,
680 .proc_handler = proc_dointvec,
683 .procname = "printk_ratelimit",
684 .data = &printk_ratelimit_state.interval,
685 .maxlen = sizeof(int),
686 .mode = 0644,
687 .proc_handler = proc_dointvec_jiffies,
690 .procname = "printk_ratelimit_burst",
691 .data = &printk_ratelimit_state.burst,
692 .maxlen = sizeof(int),
693 .mode = 0644,
694 .proc_handler = proc_dointvec,
697 .procname = "printk_delay",
698 .data = &printk_delay_msec,
699 .maxlen = sizeof(int),
700 .mode = 0644,
701 .proc_handler = proc_dointvec_minmax,
702 .extra1 = &zero,
703 .extra2 = &ten_thousand,
705 #endif
707 .procname = "ngroups_max",
708 .data = &ngroups_max,
709 .maxlen = sizeof (int),
710 .mode = 0444,
711 .proc_handler = proc_dointvec,
713 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
715 .procname = "unknown_nmi_panic",
716 .data = &unknown_nmi_panic,
717 .maxlen = sizeof (int),
718 .mode = 0644,
719 .proc_handler = proc_dointvec,
722 .procname = "nmi_watchdog",
723 .data = &nmi_watchdog_enabled,
724 .maxlen = sizeof (int),
725 .mode = 0644,
726 .proc_handler = proc_nmi_enabled,
728 #endif
729 #if defined(CONFIG_X86)
731 .procname = "panic_on_unrecovered_nmi",
732 .data = &panic_on_unrecovered_nmi,
733 .maxlen = sizeof(int),
734 .mode = 0644,
735 .proc_handler = proc_dointvec,
738 .procname = "panic_on_io_nmi",
739 .data = &panic_on_io_nmi,
740 .maxlen = sizeof(int),
741 .mode = 0644,
742 .proc_handler = proc_dointvec,
745 .procname = "bootloader_type",
746 .data = &bootloader_type,
747 .maxlen = sizeof (int),
748 .mode = 0444,
749 .proc_handler = proc_dointvec,
752 .procname = "bootloader_version",
753 .data = &bootloader_version,
754 .maxlen = sizeof (int),
755 .mode = 0444,
756 .proc_handler = proc_dointvec,
759 .procname = "kstack_depth_to_print",
760 .data = &kstack_depth_to_print,
761 .maxlen = sizeof(int),
762 .mode = 0644,
763 .proc_handler = proc_dointvec,
766 .procname = "io_delay_type",
767 .data = &io_delay_type,
768 .maxlen = sizeof(int),
769 .mode = 0644,
770 .proc_handler = proc_dointvec,
772 #endif
773 #if defined(CONFIG_MMU)
775 .procname = "randomize_va_space",
776 .data = &randomize_va_space,
777 .maxlen = sizeof(int),
778 .mode = 0644,
779 .proc_handler = proc_dointvec,
781 #endif
782 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
784 .procname = "spin_retry",
785 .data = &spin_retry,
786 .maxlen = sizeof (int),
787 .mode = 0644,
788 .proc_handler = proc_dointvec,
790 #endif
791 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
793 .procname = "acpi_video_flags",
794 .data = &acpi_realmode_flags,
795 .maxlen = sizeof (unsigned long),
796 .mode = 0644,
797 .proc_handler = proc_doulongvec_minmax,
799 #endif
800 #ifdef CONFIG_IA64
802 .procname = "ignore-unaligned-usertrap",
803 .data = &no_unaligned_warning,
804 .maxlen = sizeof (int),
805 .mode = 0644,
806 .proc_handler = proc_dointvec,
809 .procname = "unaligned-dump-stack",
810 .data = &unaligned_dump_stack,
811 .maxlen = sizeof (int),
812 .mode = 0644,
813 .proc_handler = proc_dointvec,
815 #endif
816 #ifdef CONFIG_DETECT_SOFTLOCKUP
818 .procname = "softlockup_panic",
819 .data = &softlockup_panic,
820 .maxlen = sizeof(int),
821 .mode = 0644,
822 .proc_handler = proc_dointvec_minmax,
823 .extra1 = &zero,
824 .extra2 = &one,
827 .procname = "softlockup_thresh",
828 .data = &softlockup_thresh,
829 .maxlen = sizeof(int),
830 .mode = 0644,
831 .proc_handler = proc_dosoftlockup_thresh,
832 .extra1 = &neg_one,
833 .extra2 = &sixty,
835 #endif
836 #ifdef CONFIG_DETECT_HUNG_TASK
838 .procname = "hung_task_panic",
839 .data = &sysctl_hung_task_panic,
840 .maxlen = sizeof(int),
841 .mode = 0644,
842 .proc_handler = proc_dointvec_minmax,
843 .extra1 = &zero,
844 .extra2 = &one,
847 .procname = "hung_task_check_count",
848 .data = &sysctl_hung_task_check_count,
849 .maxlen = sizeof(unsigned long),
850 .mode = 0644,
851 .proc_handler = proc_doulongvec_minmax,
854 .procname = "hung_task_timeout_secs",
855 .data = &sysctl_hung_task_timeout_secs,
856 .maxlen = sizeof(unsigned long),
857 .mode = 0644,
858 .proc_handler = proc_dohung_task_timeout_secs,
861 .procname = "hung_task_warnings",
862 .data = &sysctl_hung_task_warnings,
863 .maxlen = sizeof(unsigned long),
864 .mode = 0644,
865 .proc_handler = proc_doulongvec_minmax,
867 #endif
868 #ifdef CONFIG_COMPAT
870 .procname = "compat-log",
871 .data = &compat_log,
872 .maxlen = sizeof (int),
873 .mode = 0644,
874 .proc_handler = proc_dointvec,
876 #endif
877 #ifdef CONFIG_RT_MUTEXES
879 .procname = "max_lock_depth",
880 .data = &max_lock_depth,
881 .maxlen = sizeof(int),
882 .mode = 0644,
883 .proc_handler = proc_dointvec,
885 #endif
887 .procname = "poweroff_cmd",
888 .data = &poweroff_cmd,
889 .maxlen = POWEROFF_CMD_PATH_LEN,
890 .mode = 0644,
891 .proc_handler = proc_dostring,
893 #ifdef CONFIG_KEYS
895 .procname = "keys",
896 .mode = 0555,
897 .child = key_sysctls,
899 #endif
900 #ifdef CONFIG_RCU_TORTURE_TEST
902 .procname = "rcutorture_runnable",
903 .data = &rcutorture_runnable,
904 .maxlen = sizeof(int),
905 .mode = 0644,
906 .proc_handler = proc_dointvec,
908 #endif
909 #ifdef CONFIG_SLOW_WORK
911 .procname = "slow-work",
912 .mode = 0555,
913 .child = slow_work_sysctls,
915 #endif
916 #ifdef CONFIG_PERF_EVENTS
918 .procname = "perf_event_paranoid",
919 .data = &sysctl_perf_event_paranoid,
920 .maxlen = sizeof(sysctl_perf_event_paranoid),
921 .mode = 0644,
922 .proc_handler = proc_dointvec,
925 .procname = "perf_event_mlock_kb",
926 .data = &sysctl_perf_event_mlock,
927 .maxlen = sizeof(sysctl_perf_event_mlock),
928 .mode = 0644,
929 .proc_handler = proc_dointvec,
932 .procname = "perf_event_max_sample_rate",
933 .data = &sysctl_perf_event_sample_rate,
934 .maxlen = sizeof(sysctl_perf_event_sample_rate),
935 .mode = 0644,
936 .proc_handler = proc_dointvec,
938 #endif
939 #ifdef CONFIG_KMEMCHECK
941 .procname = "kmemcheck",
942 .data = &kmemcheck_enabled,
943 .maxlen = sizeof(int),
944 .mode = 0644,
945 .proc_handler = proc_dointvec,
947 #endif
948 #ifdef CONFIG_BLOCK
950 .procname = "blk_iopoll",
951 .data = &blk_iopoll_enabled,
952 .maxlen = sizeof(int),
953 .mode = 0644,
954 .proc_handler = proc_dointvec,
956 #endif
958 * NOTE: do not add new entries to this table unless you have read
959 * Documentation/sysctl/ctl_unnumbered.txt
964 static struct ctl_table vm_table[] = {
966 .procname = "overcommit_memory",
967 .data = &sysctl_overcommit_memory,
968 .maxlen = sizeof(sysctl_overcommit_memory),
969 .mode = 0644,
970 .proc_handler = proc_dointvec,
973 .procname = "panic_on_oom",
974 .data = &sysctl_panic_on_oom,
975 .maxlen = sizeof(sysctl_panic_on_oom),
976 .mode = 0644,
977 .proc_handler = proc_dointvec,
980 .procname = "oom_kill_allocating_task",
981 .data = &sysctl_oom_kill_allocating_task,
982 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
983 .mode = 0644,
984 .proc_handler = proc_dointvec,
987 .procname = "oom_dump_tasks",
988 .data = &sysctl_oom_dump_tasks,
989 .maxlen = sizeof(sysctl_oom_dump_tasks),
990 .mode = 0644,
991 .proc_handler = proc_dointvec,
994 .procname = "overcommit_ratio",
995 .data = &sysctl_overcommit_ratio,
996 .maxlen = sizeof(sysctl_overcommit_ratio),
997 .mode = 0644,
998 .proc_handler = proc_dointvec,
1001 .procname = "page-cluster",
1002 .data = &page_cluster,
1003 .maxlen = sizeof(int),
1004 .mode = 0644,
1005 .proc_handler = proc_dointvec,
1008 .procname = "dirty_background_ratio",
1009 .data = &dirty_background_ratio,
1010 .maxlen = sizeof(dirty_background_ratio),
1011 .mode = 0644,
1012 .proc_handler = dirty_background_ratio_handler,
1013 .extra1 = &zero,
1014 .extra2 = &one_hundred,
1017 .procname = "dirty_background_bytes",
1018 .data = &dirty_background_bytes,
1019 .maxlen = sizeof(dirty_background_bytes),
1020 .mode = 0644,
1021 .proc_handler = dirty_background_bytes_handler,
1022 .extra1 = &one_ul,
1025 .procname = "dirty_ratio",
1026 .data = &vm_dirty_ratio,
1027 .maxlen = sizeof(vm_dirty_ratio),
1028 .mode = 0644,
1029 .proc_handler = dirty_ratio_handler,
1030 .extra1 = &zero,
1031 .extra2 = &one_hundred,
1034 .procname = "dirty_bytes",
1035 .data = &vm_dirty_bytes,
1036 .maxlen = sizeof(vm_dirty_bytes),
1037 .mode = 0644,
1038 .proc_handler = dirty_bytes_handler,
1039 .extra1 = &dirty_bytes_min,
1042 .procname = "dirty_writeback_centisecs",
1043 .data = &dirty_writeback_interval,
1044 .maxlen = sizeof(dirty_writeback_interval),
1045 .mode = 0644,
1046 .proc_handler = dirty_writeback_centisecs_handler,
1049 .procname = "dirty_expire_centisecs",
1050 .data = &dirty_expire_interval,
1051 .maxlen = sizeof(dirty_expire_interval),
1052 .mode = 0644,
1053 .proc_handler = proc_dointvec,
1056 .procname = "nr_pdflush_threads",
1057 .data = &nr_pdflush_threads,
1058 .maxlen = sizeof nr_pdflush_threads,
1059 .mode = 0444 /* read-only*/,
1060 .proc_handler = proc_dointvec,
1063 .procname = "swappiness",
1064 .data = &vm_swappiness,
1065 .maxlen = sizeof(vm_swappiness),
1066 .mode = 0644,
1067 .proc_handler = proc_dointvec_minmax,
1068 .extra1 = &zero,
1069 .extra2 = &one_hundred,
1071 #ifdef CONFIG_HUGETLB_PAGE
1073 .procname = "nr_hugepages",
1074 .data = NULL,
1075 .maxlen = sizeof(unsigned long),
1076 .mode = 0644,
1077 .proc_handler = hugetlb_sysctl_handler,
1078 .extra1 = (void *)&hugetlb_zero,
1079 .extra2 = (void *)&hugetlb_infinity,
1081 #ifdef CONFIG_NUMA
1083 .procname = "nr_hugepages_mempolicy",
1084 .data = NULL,
1085 .maxlen = sizeof(unsigned long),
1086 .mode = 0644,
1087 .proc_handler = &hugetlb_mempolicy_sysctl_handler,
1088 .extra1 = (void *)&hugetlb_zero,
1089 .extra2 = (void *)&hugetlb_infinity,
1091 #endif
1093 .procname = "hugetlb_shm_group",
1094 .data = &sysctl_hugetlb_shm_group,
1095 .maxlen = sizeof(gid_t),
1096 .mode = 0644,
1097 .proc_handler = proc_dointvec,
1100 .procname = "hugepages_treat_as_movable",
1101 .data = &hugepages_treat_as_movable,
1102 .maxlen = sizeof(int),
1103 .mode = 0644,
1104 .proc_handler = hugetlb_treat_movable_handler,
1107 .procname = "nr_overcommit_hugepages",
1108 .data = NULL,
1109 .maxlen = sizeof(unsigned long),
1110 .mode = 0644,
1111 .proc_handler = hugetlb_overcommit_handler,
1112 .extra1 = (void *)&hugetlb_zero,
1113 .extra2 = (void *)&hugetlb_infinity,
1115 #endif
1117 .procname = "lowmem_reserve_ratio",
1118 .data = &sysctl_lowmem_reserve_ratio,
1119 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1120 .mode = 0644,
1121 .proc_handler = lowmem_reserve_ratio_sysctl_handler,
1124 .procname = "drop_caches",
1125 .data = &sysctl_drop_caches,
1126 .maxlen = sizeof(int),
1127 .mode = 0644,
1128 .proc_handler = drop_caches_sysctl_handler,
1130 #ifdef CONFIG_COMPACTION
1132 .procname = "compact_memory",
1133 .data = &sysctl_compact_memory,
1134 .maxlen = sizeof(int),
1135 .mode = 0200,
1136 .proc_handler = sysctl_compaction_handler,
1139 .procname = "extfrag_threshold",
1140 .data = &sysctl_extfrag_threshold,
1141 .maxlen = sizeof(int),
1142 .mode = 0644,
1143 .proc_handler = sysctl_extfrag_handler,
1144 .extra1 = &min_extfrag_threshold,
1145 .extra2 = &max_extfrag_threshold,
1148 #endif /* CONFIG_COMPACTION */
1150 .procname = "min_free_kbytes",
1151 .data = &min_free_kbytes,
1152 .maxlen = sizeof(min_free_kbytes),
1153 .mode = 0644,
1154 .proc_handler = min_free_kbytes_sysctl_handler,
1155 .extra1 = &zero,
1158 .procname = "percpu_pagelist_fraction",
1159 .data = &percpu_pagelist_fraction,
1160 .maxlen = sizeof(percpu_pagelist_fraction),
1161 .mode = 0644,
1162 .proc_handler = percpu_pagelist_fraction_sysctl_handler,
1163 .extra1 = &min_percpu_pagelist_fract,
1165 #ifdef CONFIG_MMU
1167 .procname = "max_map_count",
1168 .data = &sysctl_max_map_count,
1169 .maxlen = sizeof(sysctl_max_map_count),
1170 .mode = 0644,
1171 .proc_handler = proc_dointvec_minmax,
1172 .extra1 = &zero,
1174 #else
1176 .procname = "nr_trim_pages",
1177 .data = &sysctl_nr_trim_pages,
1178 .maxlen = sizeof(sysctl_nr_trim_pages),
1179 .mode = 0644,
1180 .proc_handler = proc_dointvec_minmax,
1181 .extra1 = &zero,
1183 #endif
1185 .procname = "laptop_mode",
1186 .data = &laptop_mode,
1187 .maxlen = sizeof(laptop_mode),
1188 .mode = 0644,
1189 .proc_handler = proc_dointvec_jiffies,
1192 .procname = "block_dump",
1193 .data = &block_dump,
1194 .maxlen = sizeof(block_dump),
1195 .mode = 0644,
1196 .proc_handler = proc_dointvec,
1197 .extra1 = &zero,
1200 .procname = "vfs_cache_pressure",
1201 .data = &sysctl_vfs_cache_pressure,
1202 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1203 .mode = 0644,
1204 .proc_handler = proc_dointvec,
1205 .extra1 = &zero,
1207 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1209 .procname = "legacy_va_layout",
1210 .data = &sysctl_legacy_va_layout,
1211 .maxlen = sizeof(sysctl_legacy_va_layout),
1212 .mode = 0644,
1213 .proc_handler = proc_dointvec,
1214 .extra1 = &zero,
1216 #endif
1217 #ifdef CONFIG_NUMA
1219 .procname = "zone_reclaim_mode",
1220 .data = &zone_reclaim_mode,
1221 .maxlen = sizeof(zone_reclaim_mode),
1222 .mode = 0644,
1223 .proc_handler = proc_dointvec,
1224 .extra1 = &zero,
1227 .procname = "min_unmapped_ratio",
1228 .data = &sysctl_min_unmapped_ratio,
1229 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1230 .mode = 0644,
1231 .proc_handler = sysctl_min_unmapped_ratio_sysctl_handler,
1232 .extra1 = &zero,
1233 .extra2 = &one_hundred,
1236 .procname = "min_slab_ratio",
1237 .data = &sysctl_min_slab_ratio,
1238 .maxlen = sizeof(sysctl_min_slab_ratio),
1239 .mode = 0644,
1240 .proc_handler = sysctl_min_slab_ratio_sysctl_handler,
1241 .extra1 = &zero,
1242 .extra2 = &one_hundred,
1244 #endif
1245 #ifdef CONFIG_SMP
1247 .procname = "stat_interval",
1248 .data = &sysctl_stat_interval,
1249 .maxlen = sizeof(sysctl_stat_interval),
1250 .mode = 0644,
1251 .proc_handler = proc_dointvec_jiffies,
1253 #endif
1254 #ifdef CONFIG_MMU
1256 .procname = "mmap_min_addr",
1257 .data = &dac_mmap_min_addr,
1258 .maxlen = sizeof(unsigned long),
1259 .mode = 0644,
1260 .proc_handler = mmap_min_addr_handler,
1262 #endif
1263 #ifdef CONFIG_NUMA
1265 .procname = "numa_zonelist_order",
1266 .data = &numa_zonelist_order,
1267 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1268 .mode = 0644,
1269 .proc_handler = numa_zonelist_order_handler,
1271 #endif
1272 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1273 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1275 .procname = "vdso_enabled",
1276 .data = &vdso_enabled,
1277 .maxlen = sizeof(vdso_enabled),
1278 .mode = 0644,
1279 .proc_handler = proc_dointvec,
1280 .extra1 = &zero,
1282 #endif
1283 #ifdef CONFIG_HIGHMEM
1285 .procname = "highmem_is_dirtyable",
1286 .data = &vm_highmem_is_dirtyable,
1287 .maxlen = sizeof(vm_highmem_is_dirtyable),
1288 .mode = 0644,
1289 .proc_handler = proc_dointvec_minmax,
1290 .extra1 = &zero,
1291 .extra2 = &one,
1293 #endif
1295 .procname = "scan_unevictable_pages",
1296 .data = &scan_unevictable_pages,
1297 .maxlen = sizeof(scan_unevictable_pages),
1298 .mode = 0644,
1299 .proc_handler = scan_unevictable_handler,
1301 #ifdef CONFIG_MEMORY_FAILURE
1303 .procname = "memory_failure_early_kill",
1304 .data = &sysctl_memory_failure_early_kill,
1305 .maxlen = sizeof(sysctl_memory_failure_early_kill),
1306 .mode = 0644,
1307 .proc_handler = proc_dointvec_minmax,
1308 .extra1 = &zero,
1309 .extra2 = &one,
1312 .procname = "memory_failure_recovery",
1313 .data = &sysctl_memory_failure_recovery,
1314 .maxlen = sizeof(sysctl_memory_failure_recovery),
1315 .mode = 0644,
1316 .proc_handler = proc_dointvec_minmax,
1317 .extra1 = &zero,
1318 .extra2 = &one,
1320 #endif
1323 * NOTE: do not add new entries to this table unless you have read
1324 * Documentation/sysctl/ctl_unnumbered.txt
1329 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1330 static struct ctl_table binfmt_misc_table[] = {
1333 #endif
1335 static struct ctl_table fs_table[] = {
1337 .procname = "inode-nr",
1338 .data = &inodes_stat,
1339 .maxlen = 2*sizeof(int),
1340 .mode = 0444,
1341 .proc_handler = proc_dointvec,
1344 .procname = "inode-state",
1345 .data = &inodes_stat,
1346 .maxlen = 7*sizeof(int),
1347 .mode = 0444,
1348 .proc_handler = proc_dointvec,
1351 .procname = "file-nr",
1352 .data = &files_stat,
1353 .maxlen = 3*sizeof(int),
1354 .mode = 0444,
1355 .proc_handler = proc_nr_files,
1358 .procname = "file-max",
1359 .data = &files_stat.max_files,
1360 .maxlen = sizeof(int),
1361 .mode = 0644,
1362 .proc_handler = proc_dointvec,
1365 .procname = "nr_open",
1366 .data = &sysctl_nr_open,
1367 .maxlen = sizeof(int),
1368 .mode = 0644,
1369 .proc_handler = proc_dointvec_minmax,
1370 .extra1 = &sysctl_nr_open_min,
1371 .extra2 = &sysctl_nr_open_max,
1374 .procname = "dentry-state",
1375 .data = &dentry_stat,
1376 .maxlen = 6*sizeof(int),
1377 .mode = 0444,
1378 .proc_handler = proc_dointvec,
1381 .procname = "overflowuid",
1382 .data = &fs_overflowuid,
1383 .maxlen = sizeof(int),
1384 .mode = 0644,
1385 .proc_handler = proc_dointvec_minmax,
1386 .extra1 = &minolduid,
1387 .extra2 = &maxolduid,
1390 .procname = "overflowgid",
1391 .data = &fs_overflowgid,
1392 .maxlen = sizeof(int),
1393 .mode = 0644,
1394 .proc_handler = proc_dointvec_minmax,
1395 .extra1 = &minolduid,
1396 .extra2 = &maxolduid,
1398 #ifdef CONFIG_FILE_LOCKING
1400 .procname = "leases-enable",
1401 .data = &leases_enable,
1402 .maxlen = sizeof(int),
1403 .mode = 0644,
1404 .proc_handler = proc_dointvec,
1406 #endif
1407 #ifdef CONFIG_DNOTIFY
1409 .procname = "dir-notify-enable",
1410 .data = &dir_notify_enable,
1411 .maxlen = sizeof(int),
1412 .mode = 0644,
1413 .proc_handler = proc_dointvec,
1415 #endif
1416 #ifdef CONFIG_MMU
1417 #ifdef CONFIG_FILE_LOCKING
1419 .procname = "lease-break-time",
1420 .data = &lease_break_time,
1421 .maxlen = sizeof(int),
1422 .mode = 0644,
1423 .proc_handler = proc_dointvec,
1425 #endif
1426 #ifdef CONFIG_AIO
1428 .procname = "aio-nr",
1429 .data = &aio_nr,
1430 .maxlen = sizeof(aio_nr),
1431 .mode = 0444,
1432 .proc_handler = proc_doulongvec_minmax,
1435 .procname = "aio-max-nr",
1436 .data = &aio_max_nr,
1437 .maxlen = sizeof(aio_max_nr),
1438 .mode = 0644,
1439 .proc_handler = proc_doulongvec_minmax,
1441 #endif /* CONFIG_AIO */
1442 #ifdef CONFIG_INOTIFY_USER
1444 .procname = "inotify",
1445 .mode = 0555,
1446 .child = inotify_table,
1448 #endif
1449 #ifdef CONFIG_EPOLL
1451 .procname = "epoll",
1452 .mode = 0555,
1453 .child = epoll_table,
1455 #endif
1456 #endif
1458 .procname = "suid_dumpable",
1459 .data = &suid_dumpable,
1460 .maxlen = sizeof(int),
1461 .mode = 0644,
1462 .proc_handler = proc_dointvec_minmax,
1463 .extra1 = &zero,
1464 .extra2 = &two,
1466 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1468 .procname = "binfmt_misc",
1469 .mode = 0555,
1470 .child = binfmt_misc_table,
1472 #endif
1474 .procname = "pipe-max-size",
1475 .data = &pipe_max_size,
1476 .maxlen = sizeof(int),
1477 .mode = 0644,
1478 .proc_handler = &pipe_proc_fn,
1479 .extra1 = &pipe_min_size,
1482 * NOTE: do not add new entries to this table unless you have read
1483 * Documentation/sysctl/ctl_unnumbered.txt
1488 static struct ctl_table debug_table[] = {
1489 #if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_SPARC) || \
1490 defined(CONFIG_S390)
1492 .procname = "exception-trace",
1493 .data = &show_unhandled_signals,
1494 .maxlen = sizeof(int),
1495 .mode = 0644,
1496 .proc_handler = proc_dointvec
1498 #endif
1499 #if defined(CONFIG_OPTPROBES)
1501 .procname = "kprobes-optimization",
1502 .data = &sysctl_kprobes_optimization,
1503 .maxlen = sizeof(int),
1504 .mode = 0644,
1505 .proc_handler = proc_kprobes_optimization_handler,
1506 .extra1 = &zero,
1507 .extra2 = &one,
1509 #endif
1513 static struct ctl_table dev_table[] = {
1517 static DEFINE_SPINLOCK(sysctl_lock);
1519 /* called under sysctl_lock */
1520 static int use_table(struct ctl_table_header *p)
1522 if (unlikely(p->unregistering))
1523 return 0;
1524 p->used++;
1525 return 1;
1528 /* called under sysctl_lock */
1529 static void unuse_table(struct ctl_table_header *p)
1531 if (!--p->used)
1532 if (unlikely(p->unregistering))
1533 complete(p->unregistering);
1536 /* called under sysctl_lock, will reacquire if has to wait */
1537 static void start_unregistering(struct ctl_table_header *p)
1540 * if p->used is 0, nobody will ever touch that entry again;
1541 * we'll eliminate all paths to it before dropping sysctl_lock
1543 if (unlikely(p->used)) {
1544 struct completion wait;
1545 init_completion(&wait);
1546 p->unregistering = &wait;
1547 spin_unlock(&sysctl_lock);
1548 wait_for_completion(&wait);
1549 spin_lock(&sysctl_lock);
1550 } else {
1551 /* anything non-NULL; we'll never dereference it */
1552 p->unregistering = ERR_PTR(-EINVAL);
1555 * do not remove from the list until nobody holds it; walking the
1556 * list in do_sysctl() relies on that.
1558 list_del_init(&p->ctl_entry);
1561 void sysctl_head_get(struct ctl_table_header *head)
1563 spin_lock(&sysctl_lock);
1564 head->count++;
1565 spin_unlock(&sysctl_lock);
1568 void sysctl_head_put(struct ctl_table_header *head)
1570 spin_lock(&sysctl_lock);
1571 if (!--head->count)
1572 kfree(head);
1573 spin_unlock(&sysctl_lock);
1576 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1578 if (!head)
1579 BUG();
1580 spin_lock(&sysctl_lock);
1581 if (!use_table(head))
1582 head = ERR_PTR(-ENOENT);
1583 spin_unlock(&sysctl_lock);
1584 return head;
1587 void sysctl_head_finish(struct ctl_table_header *head)
1589 if (!head)
1590 return;
1591 spin_lock(&sysctl_lock);
1592 unuse_table(head);
1593 spin_unlock(&sysctl_lock);
1596 static struct ctl_table_set *
1597 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1599 struct ctl_table_set *set = &root->default_set;
1600 if (root->lookup)
1601 set = root->lookup(root, namespaces);
1602 return set;
1605 static struct list_head *
1606 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1608 struct ctl_table_set *set = lookup_header_set(root, namespaces);
1609 return &set->list;
1612 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1613 struct ctl_table_header *prev)
1615 struct ctl_table_root *root;
1616 struct list_head *header_list;
1617 struct ctl_table_header *head;
1618 struct list_head *tmp;
1620 spin_lock(&sysctl_lock);
1621 if (prev) {
1622 head = prev;
1623 tmp = &prev->ctl_entry;
1624 unuse_table(prev);
1625 goto next;
1627 tmp = &root_table_header.ctl_entry;
1628 for (;;) {
1629 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1631 if (!use_table(head))
1632 goto next;
1633 spin_unlock(&sysctl_lock);
1634 return head;
1635 next:
1636 root = head->root;
1637 tmp = tmp->next;
1638 header_list = lookup_header_list(root, namespaces);
1639 if (tmp != header_list)
1640 continue;
1642 do {
1643 root = list_entry(root->root_list.next,
1644 struct ctl_table_root, root_list);
1645 if (root == &sysctl_table_root)
1646 goto out;
1647 header_list = lookup_header_list(root, namespaces);
1648 } while (list_empty(header_list));
1649 tmp = header_list->next;
1651 out:
1652 spin_unlock(&sysctl_lock);
1653 return NULL;
1656 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1658 return __sysctl_head_next(current->nsproxy, prev);
1661 void register_sysctl_root(struct ctl_table_root *root)
1663 spin_lock(&sysctl_lock);
1664 list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1665 spin_unlock(&sysctl_lock);
1669 * sysctl_perm does NOT grant the superuser all rights automatically, because
1670 * some sysctl variables are readonly even to root.
1673 static int test_perm(int mode, int op)
1675 if (!current_euid())
1676 mode >>= 6;
1677 else if (in_egroup_p(0))
1678 mode >>= 3;
1679 if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1680 return 0;
1681 return -EACCES;
1684 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1686 int error;
1687 int mode;
1689 error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1690 if (error)
1691 return error;
1693 if (root->permissions)
1694 mode = root->permissions(root, current->nsproxy, table);
1695 else
1696 mode = table->mode;
1698 return test_perm(mode, op);
1701 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1703 for (; table->procname; table++) {
1704 table->parent = parent;
1705 if (table->child)
1706 sysctl_set_parent(table, table->child);
1710 static __init int sysctl_init(void)
1712 sysctl_set_parent(NULL, root_table);
1713 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1715 int err;
1716 err = sysctl_check_table(current->nsproxy, root_table);
1718 #endif
1719 return 0;
1722 core_initcall(sysctl_init);
1724 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1725 struct ctl_table *table)
1727 struct ctl_table *p;
1728 const char *s = branch->procname;
1730 /* branch should have named subdirectory as its first element */
1731 if (!s || !branch->child)
1732 return NULL;
1734 /* ... and nothing else */
1735 if (branch[1].procname)
1736 return NULL;
1738 /* table should contain subdirectory with the same name */
1739 for (p = table; p->procname; p++) {
1740 if (!p->child)
1741 continue;
1742 if (p->procname && strcmp(p->procname, s) == 0)
1743 return p;
1745 return NULL;
1748 /* see if attaching q to p would be an improvement */
1749 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1751 struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1752 struct ctl_table *next;
1753 int is_better = 0;
1754 int not_in_parent = !p->attached_by;
1756 while ((next = is_branch_in(by, to)) != NULL) {
1757 if (by == q->attached_by)
1758 is_better = 1;
1759 if (to == p->attached_by)
1760 not_in_parent = 1;
1761 by = by->child;
1762 to = next->child;
1765 if (is_better && not_in_parent) {
1766 q->attached_by = by;
1767 q->attached_to = to;
1768 q->parent = p;
1773 * __register_sysctl_paths - register a sysctl hierarchy
1774 * @root: List of sysctl headers to register on
1775 * @namespaces: Data to compute which lists of sysctl entries are visible
1776 * @path: The path to the directory the sysctl table is in.
1777 * @table: the top-level table structure
1779 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1780 * array. A completely 0 filled entry terminates the table.
1782 * The members of the &struct ctl_table structure are used as follows:
1784 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1785 * enter a sysctl file
1787 * data - a pointer to data for use by proc_handler
1789 * maxlen - the maximum size in bytes of the data
1791 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1793 * child - a pointer to the child sysctl table if this entry is a directory, or
1794 * %NULL.
1796 * proc_handler - the text handler routine (described below)
1798 * de - for internal use by the sysctl routines
1800 * extra1, extra2 - extra pointers usable by the proc handler routines
1802 * Leaf nodes in the sysctl tree will be represented by a single file
1803 * under /proc; non-leaf nodes will be represented by directories.
1805 * sysctl(2) can automatically manage read and write requests through
1806 * the sysctl table. The data and maxlen fields of the ctl_table
1807 * struct enable minimal validation of the values being written to be
1808 * performed, and the mode field allows minimal authentication.
1810 * There must be a proc_handler routine for any terminal nodes
1811 * mirrored under /proc/sys (non-terminals are handled by a built-in
1812 * directory handler). Several default handlers are available to
1813 * cover common cases -
1815 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1816 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1817 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1819 * It is the handler's job to read the input buffer from user memory
1820 * and process it. The handler should return 0 on success.
1822 * This routine returns %NULL on a failure to register, and a pointer
1823 * to the table header on success.
1825 struct ctl_table_header *__register_sysctl_paths(
1826 struct ctl_table_root *root,
1827 struct nsproxy *namespaces,
1828 const struct ctl_path *path, struct ctl_table *table)
1830 struct ctl_table_header *header;
1831 struct ctl_table *new, **prevp;
1832 unsigned int n, npath;
1833 struct ctl_table_set *set;
1835 /* Count the path components */
1836 for (npath = 0; path[npath].procname; ++npath)
1840 * For each path component, allocate a 2-element ctl_table array.
1841 * The first array element will be filled with the sysctl entry
1842 * for this, the second will be the sentinel (procname == 0).
1844 * We allocate everything in one go so that we don't have to
1845 * worry about freeing additional memory in unregister_sysctl_table.
1847 header = kzalloc(sizeof(struct ctl_table_header) +
1848 (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
1849 if (!header)
1850 return NULL;
1852 new = (struct ctl_table *) (header + 1);
1854 /* Now connect the dots */
1855 prevp = &header->ctl_table;
1856 for (n = 0; n < npath; ++n, ++path) {
1857 /* Copy the procname */
1858 new->procname = path->procname;
1859 new->mode = 0555;
1861 *prevp = new;
1862 prevp = &new->child;
1864 new += 2;
1866 *prevp = table;
1867 header->ctl_table_arg = table;
1869 INIT_LIST_HEAD(&header->ctl_entry);
1870 header->used = 0;
1871 header->unregistering = NULL;
1872 header->root = root;
1873 sysctl_set_parent(NULL, header->ctl_table);
1874 header->count = 1;
1875 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1876 if (sysctl_check_table(namespaces, header->ctl_table)) {
1877 kfree(header);
1878 return NULL;
1880 #endif
1881 spin_lock(&sysctl_lock);
1882 header->set = lookup_header_set(root, namespaces);
1883 header->attached_by = header->ctl_table;
1884 header->attached_to = root_table;
1885 header->parent = &root_table_header;
1886 for (set = header->set; set; set = set->parent) {
1887 struct ctl_table_header *p;
1888 list_for_each_entry(p, &set->list, ctl_entry) {
1889 if (p->unregistering)
1890 continue;
1891 try_attach(p, header);
1894 header->parent->count++;
1895 list_add_tail(&header->ctl_entry, &header->set->list);
1896 spin_unlock(&sysctl_lock);
1898 return header;
1902 * register_sysctl_table_path - register a sysctl table hierarchy
1903 * @path: The path to the directory the sysctl table is in.
1904 * @table: the top-level table structure
1906 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1907 * array. A completely 0 filled entry terminates the table.
1909 * See __register_sysctl_paths for more details.
1911 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1912 struct ctl_table *table)
1914 return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
1915 path, table);
1919 * register_sysctl_table - register a sysctl table hierarchy
1920 * @table: the top-level table structure
1922 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1923 * array. A completely 0 filled entry terminates the table.
1925 * See register_sysctl_paths for more details.
1927 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
1929 static const struct ctl_path null_path[] = { {} };
1931 return register_sysctl_paths(null_path, table);
1935 * unregister_sysctl_table - unregister a sysctl table hierarchy
1936 * @header: the header returned from register_sysctl_table
1938 * Unregisters the sysctl table and all children. proc entries may not
1939 * actually be removed until they are no longer used by anyone.
1941 void unregister_sysctl_table(struct ctl_table_header * header)
1943 might_sleep();
1945 if (header == NULL)
1946 return;
1948 spin_lock(&sysctl_lock);
1949 start_unregistering(header);
1950 if (!--header->parent->count) {
1951 WARN_ON(1);
1952 kfree(header->parent);
1954 if (!--header->count)
1955 kfree(header);
1956 spin_unlock(&sysctl_lock);
1959 int sysctl_is_seen(struct ctl_table_header *p)
1961 struct ctl_table_set *set = p->set;
1962 int res;
1963 spin_lock(&sysctl_lock);
1964 if (p->unregistering)
1965 res = 0;
1966 else if (!set->is_seen)
1967 res = 1;
1968 else
1969 res = set->is_seen(set);
1970 spin_unlock(&sysctl_lock);
1971 return res;
1974 void setup_sysctl_set(struct ctl_table_set *p,
1975 struct ctl_table_set *parent,
1976 int (*is_seen)(struct ctl_table_set *))
1978 INIT_LIST_HEAD(&p->list);
1979 p->parent = parent ? parent : &sysctl_table_root.default_set;
1980 p->is_seen = is_seen;
1983 #else /* !CONFIG_SYSCTL */
1984 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
1986 return NULL;
1989 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1990 struct ctl_table *table)
1992 return NULL;
1995 void unregister_sysctl_table(struct ctl_table_header * table)
1999 void setup_sysctl_set(struct ctl_table_set *p,
2000 struct ctl_table_set *parent,
2001 int (*is_seen)(struct ctl_table_set *))
2005 void sysctl_head_put(struct ctl_table_header *head)
2009 #endif /* CONFIG_SYSCTL */
2012 * /proc/sys support
2015 #ifdef CONFIG_PROC_SYSCTL
2017 static int _proc_do_string(void* data, int maxlen, int write,
2018 void __user *buffer,
2019 size_t *lenp, loff_t *ppos)
2021 size_t len;
2022 char __user *p;
2023 char c;
2025 if (!data || !maxlen || !*lenp) {
2026 *lenp = 0;
2027 return 0;
2030 if (write) {
2031 len = 0;
2032 p = buffer;
2033 while (len < *lenp) {
2034 if (get_user(c, p++))
2035 return -EFAULT;
2036 if (c == 0 || c == '\n')
2037 break;
2038 len++;
2040 if (len >= maxlen)
2041 len = maxlen-1;
2042 if(copy_from_user(data, buffer, len))
2043 return -EFAULT;
2044 ((char *) data)[len] = 0;
2045 *ppos += *lenp;
2046 } else {
2047 len = strlen(data);
2048 if (len > maxlen)
2049 len = maxlen;
2051 if (*ppos > len) {
2052 *lenp = 0;
2053 return 0;
2056 data += *ppos;
2057 len -= *ppos;
2059 if (len > *lenp)
2060 len = *lenp;
2061 if (len)
2062 if(copy_to_user(buffer, data, len))
2063 return -EFAULT;
2064 if (len < *lenp) {
2065 if(put_user('\n', ((char __user *) buffer) + len))
2066 return -EFAULT;
2067 len++;
2069 *lenp = len;
2070 *ppos += len;
2072 return 0;
2076 * proc_dostring - read a string sysctl
2077 * @table: the sysctl table
2078 * @write: %TRUE if this is a write to the sysctl file
2079 * @buffer: the user buffer
2080 * @lenp: the size of the user buffer
2081 * @ppos: file position
2083 * Reads/writes a string from/to the user buffer. If the kernel
2084 * buffer provided is not large enough to hold the string, the
2085 * string is truncated. The copied string is %NULL-terminated.
2086 * If the string is being read by the user process, it is copied
2087 * and a newline '\n' is added. It is truncated if the buffer is
2088 * not large enough.
2090 * Returns 0 on success.
2092 int proc_dostring(struct ctl_table *table, int write,
2093 void __user *buffer, size_t *lenp, loff_t *ppos)
2095 return _proc_do_string(table->data, table->maxlen, write,
2096 buffer, lenp, ppos);
2099 static size_t proc_skip_spaces(char **buf)
2101 size_t ret;
2102 char *tmp = skip_spaces(*buf);
2103 ret = tmp - *buf;
2104 *buf = tmp;
2105 return ret;
2108 static void proc_skip_char(char **buf, size_t *size, const char v)
2110 while (*size) {
2111 if (**buf != v)
2112 break;
2113 (*size)--;
2114 (*buf)++;
2118 #define TMPBUFLEN 22
2120 * proc_get_long - reads an ASCII formatted integer from a user buffer
2122 * @buf: a kernel buffer
2123 * @size: size of the kernel buffer
2124 * @val: this is where the number will be stored
2125 * @neg: set to %TRUE if number is negative
2126 * @perm_tr: a vector which contains the allowed trailers
2127 * @perm_tr_len: size of the perm_tr vector
2128 * @tr: pointer to store the trailer character
2130 * In case of success %0 is returned and @buf and @size are updated with
2131 * the amount of bytes read. If @tr is non-NULL and a trailing
2132 * character exists (size is non-zero after returning from this
2133 * function), @tr is updated with the trailing character.
2135 static int proc_get_long(char **buf, size_t *size,
2136 unsigned long *val, bool *neg,
2137 const char *perm_tr, unsigned perm_tr_len, char *tr)
2139 int len;
2140 char *p, tmp[TMPBUFLEN];
2142 if (!*size)
2143 return -EINVAL;
2145 len = *size;
2146 if (len > TMPBUFLEN - 1)
2147 len = TMPBUFLEN - 1;
2149 memcpy(tmp, *buf, len);
2151 tmp[len] = 0;
2152 p = tmp;
2153 if (*p == '-' && *size > 1) {
2154 *neg = true;
2155 p++;
2156 } else
2157 *neg = false;
2158 if (!isdigit(*p))
2159 return -EINVAL;
2161 *val = simple_strtoul(p, &p, 0);
2163 len = p - tmp;
2165 /* We don't know if the next char is whitespace thus we may accept
2166 * invalid integers (e.g. 1234...a) or two integers instead of one
2167 * (e.g. 123...1). So lets not allow such large numbers. */
2168 if (len == TMPBUFLEN - 1)
2169 return -EINVAL;
2171 if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
2172 return -EINVAL;
2174 if (tr && (len < *size))
2175 *tr = *p;
2177 *buf += len;
2178 *size -= len;
2180 return 0;
2184 * proc_put_long - converts an integer to a decimal ASCII formatted string
2186 * @buf: the user buffer
2187 * @size: the size of the user buffer
2188 * @val: the integer to be converted
2189 * @neg: sign of the number, %TRUE for negative
2191 * In case of success %0 is returned and @buf and @size are updated with
2192 * the amount of bytes written.
2194 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2195 bool neg)
2197 int len;
2198 char tmp[TMPBUFLEN], *p = tmp;
2200 sprintf(p, "%s%lu", neg ? "-" : "", val);
2201 len = strlen(tmp);
2202 if (len > *size)
2203 len = *size;
2204 if (copy_to_user(*buf, tmp, len))
2205 return -EFAULT;
2206 *size -= len;
2207 *buf += len;
2208 return 0;
2210 #undef TMPBUFLEN
2212 static int proc_put_char(void __user **buf, size_t *size, char c)
2214 if (*size) {
2215 char __user **buffer = (char __user **)buf;
2216 if (put_user(c, *buffer))
2217 return -EFAULT;
2218 (*size)--, (*buffer)++;
2219 *buf = *buffer;
2221 return 0;
2224 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
2225 int *valp,
2226 int write, void *data)
2228 if (write) {
2229 *valp = *negp ? -*lvalp : *lvalp;
2230 } else {
2231 int val = *valp;
2232 if (val < 0) {
2233 *negp = true;
2234 *lvalp = (unsigned long)-val;
2235 } else {
2236 *negp = false;
2237 *lvalp = (unsigned long)val;
2240 return 0;
2243 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2245 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2246 int write, void __user *buffer,
2247 size_t *lenp, loff_t *ppos,
2248 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2249 int write, void *data),
2250 void *data)
2252 int *i, vleft, first = 1, err = 0;
2253 unsigned long page = 0;
2254 size_t left;
2255 char *kbuf;
2257 if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2258 *lenp = 0;
2259 return 0;
2262 i = (int *) tbl_data;
2263 vleft = table->maxlen / sizeof(*i);
2264 left = *lenp;
2266 if (!conv)
2267 conv = do_proc_dointvec_conv;
2269 if (write) {
2270 if (left > PAGE_SIZE - 1)
2271 left = PAGE_SIZE - 1;
2272 page = __get_free_page(GFP_TEMPORARY);
2273 kbuf = (char *) page;
2274 if (!kbuf)
2275 return -ENOMEM;
2276 if (copy_from_user(kbuf, buffer, left)) {
2277 err = -EFAULT;
2278 goto free;
2280 kbuf[left] = 0;
2283 for (; left && vleft--; i++, first=0) {
2284 unsigned long lval;
2285 bool neg;
2287 if (write) {
2288 left -= proc_skip_spaces(&kbuf);
2290 if (!left)
2291 break;
2292 err = proc_get_long(&kbuf, &left, &lval, &neg,
2293 proc_wspace_sep,
2294 sizeof(proc_wspace_sep), NULL);
2295 if (err)
2296 break;
2297 if (conv(&neg, &lval, i, 1, data)) {
2298 err = -EINVAL;
2299 break;
2301 } else {
2302 if (conv(&neg, &lval, i, 0, data)) {
2303 err = -EINVAL;
2304 break;
2306 if (!first)
2307 err = proc_put_char(&buffer, &left, '\t');
2308 if (err)
2309 break;
2310 err = proc_put_long(&buffer, &left, lval, neg);
2311 if (err)
2312 break;
2316 if (!write && !first && left && !err)
2317 err = proc_put_char(&buffer, &left, '\n');
2318 if (write && !err && left)
2319 left -= proc_skip_spaces(&kbuf);
2320 free:
2321 if (write) {
2322 free_page(page);
2323 if (first)
2324 return err ? : -EINVAL;
2326 *lenp -= left;
2327 *ppos += *lenp;
2328 return err;
2331 static int do_proc_dointvec(struct ctl_table *table, int write,
2332 void __user *buffer, size_t *lenp, loff_t *ppos,
2333 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2334 int write, void *data),
2335 void *data)
2337 return __do_proc_dointvec(table->data, table, write,
2338 buffer, lenp, ppos, conv, data);
2342 * proc_dointvec - read a vector of integers
2343 * @table: the sysctl table
2344 * @write: %TRUE if this is a write to the sysctl file
2345 * @buffer: the user buffer
2346 * @lenp: the size of the user buffer
2347 * @ppos: file position
2349 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2350 * values from/to the user buffer, treated as an ASCII string.
2352 * Returns 0 on success.
2354 int proc_dointvec(struct ctl_table *table, int write,
2355 void __user *buffer, size_t *lenp, loff_t *ppos)
2357 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2358 NULL,NULL);
2362 * Taint values can only be increased
2363 * This means we can safely use a temporary.
2365 static int proc_taint(struct ctl_table *table, int write,
2366 void __user *buffer, size_t *lenp, loff_t *ppos)
2368 struct ctl_table t;
2369 unsigned long tmptaint = get_taint();
2370 int err;
2372 if (write && !capable(CAP_SYS_ADMIN))
2373 return -EPERM;
2375 t = *table;
2376 t.data = &tmptaint;
2377 err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2378 if (err < 0)
2379 return err;
2381 if (write) {
2383 * Poor man's atomic or. Not worth adding a primitive
2384 * to everyone's atomic.h for this
2386 int i;
2387 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2388 if ((tmptaint >> i) & 1)
2389 add_taint(i);
2393 return err;
2396 struct do_proc_dointvec_minmax_conv_param {
2397 int *min;
2398 int *max;
2401 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2402 int *valp,
2403 int write, void *data)
2405 struct do_proc_dointvec_minmax_conv_param *param = data;
2406 if (write) {
2407 int val = *negp ? -*lvalp : *lvalp;
2408 if ((param->min && *param->min > val) ||
2409 (param->max && *param->max < val))
2410 return -EINVAL;
2411 *valp = val;
2412 } else {
2413 int val = *valp;
2414 if (val < 0) {
2415 *negp = true;
2416 *lvalp = (unsigned long)-val;
2417 } else {
2418 *negp = false;
2419 *lvalp = (unsigned long)val;
2422 return 0;
2426 * proc_dointvec_minmax - read a vector of integers with min/max values
2427 * @table: the sysctl table
2428 * @write: %TRUE if this is a write to the sysctl file
2429 * @buffer: the user buffer
2430 * @lenp: the size of the user buffer
2431 * @ppos: file position
2433 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2434 * values from/to the user buffer, treated as an ASCII string.
2436 * This routine will ensure the values are within the range specified by
2437 * table->extra1 (min) and table->extra2 (max).
2439 * Returns 0 on success.
2441 int proc_dointvec_minmax(struct ctl_table *table, int write,
2442 void __user *buffer, size_t *lenp, loff_t *ppos)
2444 struct do_proc_dointvec_minmax_conv_param param = {
2445 .min = (int *) table->extra1,
2446 .max = (int *) table->extra2,
2448 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2449 do_proc_dointvec_minmax_conv, &param);
2452 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2453 void __user *buffer,
2454 size_t *lenp, loff_t *ppos,
2455 unsigned long convmul,
2456 unsigned long convdiv)
2458 unsigned long *i, *min, *max;
2459 int vleft, first = 1, err = 0;
2460 unsigned long page = 0;
2461 size_t left;
2462 char *kbuf;
2464 if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2465 *lenp = 0;
2466 return 0;
2469 i = (unsigned long *) data;
2470 min = (unsigned long *) table->extra1;
2471 max = (unsigned long *) table->extra2;
2472 vleft = table->maxlen / sizeof(unsigned long);
2473 left = *lenp;
2475 if (write) {
2476 if (left > PAGE_SIZE - 1)
2477 left = PAGE_SIZE - 1;
2478 page = __get_free_page(GFP_TEMPORARY);
2479 kbuf = (char *) page;
2480 if (!kbuf)
2481 return -ENOMEM;
2482 if (copy_from_user(kbuf, buffer, left)) {
2483 err = -EFAULT;
2484 goto free;
2486 kbuf[left] = 0;
2489 for (; left && vleft--; i++, min++, max++, first=0) {
2490 unsigned long val;
2492 if (write) {
2493 bool neg;
2495 left -= proc_skip_spaces(&kbuf);
2497 err = proc_get_long(&kbuf, &left, &val, &neg,
2498 proc_wspace_sep,
2499 sizeof(proc_wspace_sep), NULL);
2500 if (err)
2501 break;
2502 if (neg)
2503 continue;
2504 if ((min && val < *min) || (max && val > *max))
2505 continue;
2506 *i = val;
2507 } else {
2508 val = convdiv * (*i) / convmul;
2509 if (!first)
2510 err = proc_put_char(&buffer, &left, '\t');
2511 err = proc_put_long(&buffer, &left, val, false);
2512 if (err)
2513 break;
2517 if (!write && !first && left && !err)
2518 err = proc_put_char(&buffer, &left, '\n');
2519 if (write && !err)
2520 left -= proc_skip_spaces(&kbuf);
2521 free:
2522 if (write) {
2523 free_page(page);
2524 if (first)
2525 return err ? : -EINVAL;
2527 *lenp -= left;
2528 *ppos += *lenp;
2529 return err;
2532 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2533 void __user *buffer,
2534 size_t *lenp, loff_t *ppos,
2535 unsigned long convmul,
2536 unsigned long convdiv)
2538 return __do_proc_doulongvec_minmax(table->data, table, write,
2539 buffer, lenp, ppos, convmul, convdiv);
2543 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2544 * @table: the sysctl table
2545 * @write: %TRUE if this is a write to the sysctl file
2546 * @buffer: the user buffer
2547 * @lenp: the size of the user buffer
2548 * @ppos: file position
2550 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2551 * values from/to the user buffer, treated as an ASCII string.
2553 * This routine will ensure the values are within the range specified by
2554 * table->extra1 (min) and table->extra2 (max).
2556 * Returns 0 on success.
2558 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2559 void __user *buffer, size_t *lenp, loff_t *ppos)
2561 return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2565 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2566 * @table: the sysctl table
2567 * @write: %TRUE if this is a write to the sysctl file
2568 * @buffer: the user buffer
2569 * @lenp: the size of the user buffer
2570 * @ppos: file position
2572 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2573 * values from/to the user buffer, treated as an ASCII string. The values
2574 * are treated as milliseconds, and converted to jiffies when they are stored.
2576 * This routine will ensure the values are within the range specified by
2577 * table->extra1 (min) and table->extra2 (max).
2579 * Returns 0 on success.
2581 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2582 void __user *buffer,
2583 size_t *lenp, loff_t *ppos)
2585 return do_proc_doulongvec_minmax(table, write, buffer,
2586 lenp, ppos, HZ, 1000l);
2590 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2591 int *valp,
2592 int write, void *data)
2594 if (write) {
2595 if (*lvalp > LONG_MAX / HZ)
2596 return 1;
2597 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2598 } else {
2599 int val = *valp;
2600 unsigned long lval;
2601 if (val < 0) {
2602 *negp = true;
2603 lval = (unsigned long)-val;
2604 } else {
2605 *negp = false;
2606 lval = (unsigned long)val;
2608 *lvalp = lval / HZ;
2610 return 0;
2613 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
2614 int *valp,
2615 int write, void *data)
2617 if (write) {
2618 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2619 return 1;
2620 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2621 } else {
2622 int val = *valp;
2623 unsigned long lval;
2624 if (val < 0) {
2625 *negp = true;
2626 lval = (unsigned long)-val;
2627 } else {
2628 *negp = false;
2629 lval = (unsigned long)val;
2631 *lvalp = jiffies_to_clock_t(lval);
2633 return 0;
2636 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
2637 int *valp,
2638 int write, void *data)
2640 if (write) {
2641 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2642 } else {
2643 int val = *valp;
2644 unsigned long lval;
2645 if (val < 0) {
2646 *negp = true;
2647 lval = (unsigned long)-val;
2648 } else {
2649 *negp = false;
2650 lval = (unsigned long)val;
2652 *lvalp = jiffies_to_msecs(lval);
2654 return 0;
2658 * proc_dointvec_jiffies - read a vector of integers as seconds
2659 * @table: the sysctl table
2660 * @write: %TRUE if this is a write to the sysctl file
2661 * @buffer: the user buffer
2662 * @lenp: the size of the user buffer
2663 * @ppos: file position
2665 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2666 * values from/to the user buffer, treated as an ASCII string.
2667 * The values read are assumed to be in seconds, and are converted into
2668 * jiffies.
2670 * Returns 0 on success.
2672 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2673 void __user *buffer, size_t *lenp, loff_t *ppos)
2675 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2676 do_proc_dointvec_jiffies_conv,NULL);
2680 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2681 * @table: the sysctl table
2682 * @write: %TRUE if this is a write to the sysctl file
2683 * @buffer: the user buffer
2684 * @lenp: the size of the user buffer
2685 * @ppos: pointer to the file position
2687 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2688 * values from/to the user buffer, treated as an ASCII string.
2689 * The values read are assumed to be in 1/USER_HZ seconds, and
2690 * are converted into jiffies.
2692 * Returns 0 on success.
2694 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2695 void __user *buffer, size_t *lenp, loff_t *ppos)
2697 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2698 do_proc_dointvec_userhz_jiffies_conv,NULL);
2702 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2703 * @table: the sysctl table
2704 * @write: %TRUE if this is a write to the sysctl file
2705 * @buffer: the user buffer
2706 * @lenp: the size of the user buffer
2707 * @ppos: file position
2708 * @ppos: the current position in the file
2710 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2711 * values from/to the user buffer, treated as an ASCII string.
2712 * The values read are assumed to be in 1/1000 seconds, and
2713 * are converted into jiffies.
2715 * Returns 0 on success.
2717 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2718 void __user *buffer, size_t *lenp, loff_t *ppos)
2720 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2721 do_proc_dointvec_ms_jiffies_conv, NULL);
2724 static int proc_do_cad_pid(struct ctl_table *table, int write,
2725 void __user *buffer, size_t *lenp, loff_t *ppos)
2727 struct pid *new_pid;
2728 pid_t tmp;
2729 int r;
2731 tmp = pid_vnr(cad_pid);
2733 r = __do_proc_dointvec(&tmp, table, write, buffer,
2734 lenp, ppos, NULL, NULL);
2735 if (r || !write)
2736 return r;
2738 new_pid = find_get_pid(tmp);
2739 if (!new_pid)
2740 return -ESRCH;
2742 put_pid(xchg(&cad_pid, new_pid));
2743 return 0;
2747 * proc_do_large_bitmap - read/write from/to a large bitmap
2748 * @table: the sysctl table
2749 * @write: %TRUE if this is a write to the sysctl file
2750 * @buffer: the user buffer
2751 * @lenp: the size of the user buffer
2752 * @ppos: file position
2754 * The bitmap is stored at table->data and the bitmap length (in bits)
2755 * in table->maxlen.
2757 * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2758 * large bitmaps may be represented in a compact manner. Writing into
2759 * the file will clear the bitmap then update it with the given input.
2761 * Returns 0 on success.
2763 int proc_do_large_bitmap(struct ctl_table *table, int write,
2764 void __user *buffer, size_t *lenp, loff_t *ppos)
2766 int err = 0;
2767 bool first = 1;
2768 size_t left = *lenp;
2769 unsigned long bitmap_len = table->maxlen;
2770 unsigned long *bitmap = (unsigned long *) table->data;
2771 unsigned long *tmp_bitmap = NULL;
2772 char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
2774 if (!bitmap_len || !left || (*ppos && !write)) {
2775 *lenp = 0;
2776 return 0;
2779 if (write) {
2780 unsigned long page = 0;
2781 char *kbuf;
2783 if (left > PAGE_SIZE - 1)
2784 left = PAGE_SIZE - 1;
2786 page = __get_free_page(GFP_TEMPORARY);
2787 kbuf = (char *) page;
2788 if (!kbuf)
2789 return -ENOMEM;
2790 if (copy_from_user(kbuf, buffer, left)) {
2791 free_page(page);
2792 return -EFAULT;
2794 kbuf[left] = 0;
2796 tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
2797 GFP_KERNEL);
2798 if (!tmp_bitmap) {
2799 free_page(page);
2800 return -ENOMEM;
2802 proc_skip_char(&kbuf, &left, '\n');
2803 while (!err && left) {
2804 unsigned long val_a, val_b;
2805 bool neg;
2807 err = proc_get_long(&kbuf, &left, &val_a, &neg, tr_a,
2808 sizeof(tr_a), &c);
2809 if (err)
2810 break;
2811 if (val_a >= bitmap_len || neg) {
2812 err = -EINVAL;
2813 break;
2816 val_b = val_a;
2817 if (left) {
2818 kbuf++;
2819 left--;
2822 if (c == '-') {
2823 err = proc_get_long(&kbuf, &left, &val_b,
2824 &neg, tr_b, sizeof(tr_b),
2825 &c);
2826 if (err)
2827 break;
2828 if (val_b >= bitmap_len || neg ||
2829 val_a > val_b) {
2830 err = -EINVAL;
2831 break;
2833 if (left) {
2834 kbuf++;
2835 left--;
2839 while (val_a <= val_b)
2840 set_bit(val_a++, tmp_bitmap);
2842 first = 0;
2843 proc_skip_char(&kbuf, &left, '\n');
2845 free_page(page);
2846 } else {
2847 unsigned long bit_a, bit_b = 0;
2849 while (left) {
2850 bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
2851 if (bit_a >= bitmap_len)
2852 break;
2853 bit_b = find_next_zero_bit(bitmap, bitmap_len,
2854 bit_a + 1) - 1;
2856 if (!first) {
2857 err = proc_put_char(&buffer, &left, ',');
2858 if (err)
2859 break;
2861 err = proc_put_long(&buffer, &left, bit_a, false);
2862 if (err)
2863 break;
2864 if (bit_a != bit_b) {
2865 err = proc_put_char(&buffer, &left, '-');
2866 if (err)
2867 break;
2868 err = proc_put_long(&buffer, &left, bit_b, false);
2869 if (err)
2870 break;
2873 first = 0; bit_b++;
2875 if (!err)
2876 err = proc_put_char(&buffer, &left, '\n');
2879 if (!err) {
2880 if (write) {
2881 if (*ppos)
2882 bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
2883 else
2884 memcpy(bitmap, tmp_bitmap,
2885 BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long));
2887 kfree(tmp_bitmap);
2888 *lenp -= left;
2889 *ppos += *lenp;
2890 return 0;
2891 } else {
2892 kfree(tmp_bitmap);
2893 return err;
2897 #else /* CONFIG_PROC_FS */
2899 int proc_dostring(struct ctl_table *table, int write,
2900 void __user *buffer, size_t *lenp, loff_t *ppos)
2902 return -ENOSYS;
2905 int proc_dointvec(struct ctl_table *table, int write,
2906 void __user *buffer, size_t *lenp, loff_t *ppos)
2908 return -ENOSYS;
2911 int proc_dointvec_minmax(struct ctl_table *table, int write,
2912 void __user *buffer, size_t *lenp, loff_t *ppos)
2914 return -ENOSYS;
2917 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2918 void __user *buffer, size_t *lenp, loff_t *ppos)
2920 return -ENOSYS;
2923 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2924 void __user *buffer, size_t *lenp, loff_t *ppos)
2926 return -ENOSYS;
2929 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2930 void __user *buffer, size_t *lenp, loff_t *ppos)
2932 return -ENOSYS;
2935 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2936 void __user *buffer, size_t *lenp, loff_t *ppos)
2938 return -ENOSYS;
2941 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2942 void __user *buffer,
2943 size_t *lenp, loff_t *ppos)
2945 return -ENOSYS;
2949 #endif /* CONFIG_PROC_FS */
2952 * No sense putting this after each symbol definition, twice,
2953 * exception granted :-)
2955 EXPORT_SYMBOL(proc_dointvec);
2956 EXPORT_SYMBOL(proc_dointvec_jiffies);
2957 EXPORT_SYMBOL(proc_dointvec_minmax);
2958 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2959 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2960 EXPORT_SYMBOL(proc_dostring);
2961 EXPORT_SYMBOL(proc_doulongvec_minmax);
2962 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2963 EXPORT_SYMBOL(register_sysctl_table);
2964 EXPORT_SYMBOL(register_sysctl_paths);
2965 EXPORT_SYMBOL(unregister_sysctl_table);