sysctl: Factor out sysctl_data.
[linux-2.6/kmemtrace.git] / kernel / sysctl.c
blob88c8ea8f5e8cd566fb386dcc4bf0daae8ca7c126
1 /*
2 * sysctl.c: General linux system control interface
4 * Begun 24 March 1995, Stephen Tweedie
5 * Added /proc support, Dec 1995
6 * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
7 * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
8 * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
9 * Dynamic registration fixes, Stephen Tweedie.
10 * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
11 * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
12 * Horn.
13 * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
14 * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
15 * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
16 * Wendling.
17 * The list_for_each() macro wasn't appropriate for the sysctl loop.
18 * Removed it and replaced it with older style, 03/23/00, Bill Wendling
21 #include <linux/module.h>
22 #include <linux/mm.h>
23 #include <linux/swap.h>
24 #include <linux/slab.h>
25 #include <linux/sysctl.h>
26 #include <linux/proc_fs.h>
27 #include <linux/capability.h>
28 #include <linux/ctype.h>
29 #include <linux/utsname.h>
30 #include <linux/smp_lock.h>
31 #include <linux/fs.h>
32 #include <linux/init.h>
33 #include <linux/kernel.h>
34 #include <linux/kobject.h>
35 #include <linux/net.h>
36 #include <linux/sysrq.h>
37 #include <linux/highuid.h>
38 #include <linux/writeback.h>
39 #include <linux/hugetlb.h>
40 #include <linux/security.h>
41 #include <linux/initrd.h>
42 #include <linux/times.h>
43 #include <linux/limits.h>
44 #include <linux/dcache.h>
45 #include <linux/syscalls.h>
46 #include <linux/nfs_fs.h>
47 #include <linux/acpi.h>
48 #include <linux/reboot.h>
50 #include <asm/uaccess.h>
51 #include <asm/processor.h>
53 #ifdef CONFIG_X86
54 #include <asm/nmi.h>
55 #include <asm/stacktrace.h>
56 #endif
58 #if defined(CONFIG_SYSCTL)
60 /* External variables not in a header file. */
61 extern int C_A_D;
62 extern int print_fatal_signals;
63 extern int sysctl_overcommit_memory;
64 extern int sysctl_overcommit_ratio;
65 extern int sysctl_panic_on_oom;
66 extern int sysctl_oom_kill_allocating_task;
67 extern int max_threads;
68 extern int core_uses_pid;
69 extern int suid_dumpable;
70 extern char core_pattern[];
71 extern int pid_max;
72 extern int min_free_kbytes;
73 extern int printk_ratelimit_jiffies;
74 extern int printk_ratelimit_burst;
75 extern int pid_max_min, pid_max_max;
76 extern int sysctl_drop_caches;
77 extern int percpu_pagelist_fraction;
78 extern int compat_log;
79 extern int maps_protect;
80 extern int sysctl_stat_interval;
81 extern int audit_argv_kb;
83 /* Constants used for minimum and maximum */
84 #ifdef CONFIG_DETECT_SOFTLOCKUP
85 static int one = 1;
86 static int sixty = 60;
87 #endif
89 #ifdef CONFIG_MMU
90 static int two = 2;
91 #endif
93 static int zero;
94 static int one_hundred = 100;
96 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
97 static int maxolduid = 65535;
98 static int minolduid;
99 static int min_percpu_pagelist_fract = 8;
101 static int ngroups_max = NGROUPS_MAX;
103 #ifdef CONFIG_KMOD
104 extern char modprobe_path[];
105 #endif
106 #ifdef CONFIG_CHR_DEV_SG
107 extern int sg_big_buff;
108 #endif
110 #ifdef __sparc__
111 extern char reboot_command [];
112 extern int stop_a_enabled;
113 extern int scons_pwroff;
114 #endif
116 #ifdef __hppa__
117 extern int pwrsw_enabled;
118 extern int unaligned_enabled;
119 #endif
121 #ifdef CONFIG_S390
122 #ifdef CONFIG_MATHEMU
123 extern int sysctl_ieee_emulation_warnings;
124 #endif
125 extern int sysctl_userprocess_debug;
126 extern int spin_retry;
127 #endif
129 extern int sysctl_hz_timer;
131 #ifdef CONFIG_BSD_PROCESS_ACCT
132 extern int acct_parm[];
133 #endif
135 #ifdef CONFIG_IA64
136 extern int no_unaligned_warning;
137 #endif
139 #ifdef CONFIG_RT_MUTEXES
140 extern int max_lock_depth;
141 #endif
143 #ifdef CONFIG_SYSCTL_SYSCALL
144 static int parse_table(int __user *, int, void __user *, size_t __user *,
145 void __user *, size_t, struct ctl_table *);
146 #endif
149 #ifdef CONFIG_PROC_SYSCTL
150 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
151 void __user *buffer, size_t *lenp, loff_t *ppos);
152 static int proc_dointvec_taint(struct ctl_table *table, int write, struct file *filp,
153 void __user *buffer, size_t *lenp, loff_t *ppos);
154 #endif
156 static struct ctl_table root_table[];
157 static struct ctl_table_header root_table_header =
158 { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
160 static struct ctl_table kern_table[];
161 static struct ctl_table vm_table[];
162 static struct ctl_table fs_table[];
163 static struct ctl_table debug_table[];
164 static struct ctl_table dev_table[];
165 extern struct ctl_table random_table[];
166 #ifdef CONFIG_UNIX98_PTYS
167 extern struct ctl_table pty_table[];
168 #endif
169 #ifdef CONFIG_INOTIFY_USER
170 extern struct ctl_table inotify_table[];
171 #endif
173 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
174 int sysctl_legacy_va_layout;
175 #endif
177 extern int prove_locking;
178 extern int lock_stat;
180 /* The default sysctl tables: */
182 static struct ctl_table root_table[] = {
184 .ctl_name = CTL_KERN,
185 .procname = "kernel",
186 .mode = 0555,
187 .child = kern_table,
190 .ctl_name = CTL_VM,
191 .procname = "vm",
192 .mode = 0555,
193 .child = vm_table,
195 #ifdef CONFIG_NET
197 .ctl_name = CTL_NET,
198 .procname = "net",
199 .mode = 0555,
200 .child = net_table,
202 #endif
204 .ctl_name = CTL_FS,
205 .procname = "fs",
206 .mode = 0555,
207 .child = fs_table,
210 .ctl_name = CTL_DEBUG,
211 .procname = "debug",
212 .mode = 0555,
213 .child = debug_table,
216 .ctl_name = CTL_DEV,
217 .procname = "dev",
218 .mode = 0555,
219 .child = dev_table,
222 * NOTE: do not add new entries to this table unless you have read
223 * Documentation/sysctl/ctl_unnumbered.txt
225 { .ctl_name = 0 }
228 #ifdef CONFIG_SCHED_DEBUG
229 static unsigned long min_sched_granularity_ns = 100000; /* 100 usecs */
230 static unsigned long max_sched_granularity_ns = 1000000000; /* 1 second */
231 static unsigned long min_wakeup_granularity_ns; /* 0 usecs */
232 static unsigned long max_wakeup_granularity_ns = 1000000000; /* 1 second */
233 #endif
235 static struct ctl_table kern_table[] = {
236 #ifdef CONFIG_SCHED_DEBUG
238 .ctl_name = CTL_UNNUMBERED,
239 .procname = "sched_nr_latency",
240 .data = &sysctl_sched_nr_latency,
241 .maxlen = sizeof(unsigned int),
242 .mode = 0644,
243 .proc_handler = &proc_dointvec,
246 .ctl_name = CTL_UNNUMBERED,
247 .procname = "sched_latency_ns",
248 .data = &sysctl_sched_latency,
249 .maxlen = sizeof(unsigned int),
250 .mode = 0644,
251 .proc_handler = &proc_dointvec_minmax,
252 .strategy = &sysctl_intvec,
253 .extra1 = &min_sched_granularity_ns,
254 .extra2 = &max_sched_granularity_ns,
257 .ctl_name = CTL_UNNUMBERED,
258 .procname = "sched_wakeup_granularity_ns",
259 .data = &sysctl_sched_wakeup_granularity,
260 .maxlen = sizeof(unsigned int),
261 .mode = 0644,
262 .proc_handler = &proc_dointvec_minmax,
263 .strategy = &sysctl_intvec,
264 .extra1 = &min_wakeup_granularity_ns,
265 .extra2 = &max_wakeup_granularity_ns,
268 .ctl_name = CTL_UNNUMBERED,
269 .procname = "sched_batch_wakeup_granularity_ns",
270 .data = &sysctl_sched_batch_wakeup_granularity,
271 .maxlen = sizeof(unsigned int),
272 .mode = 0644,
273 .proc_handler = &proc_dointvec_minmax,
274 .strategy = &sysctl_intvec,
275 .extra1 = &min_wakeup_granularity_ns,
276 .extra2 = &max_wakeup_granularity_ns,
279 .ctl_name = CTL_UNNUMBERED,
280 .procname = "sched_child_runs_first",
281 .data = &sysctl_sched_child_runs_first,
282 .maxlen = sizeof(unsigned int),
283 .mode = 0644,
284 .proc_handler = &proc_dointvec,
287 .ctl_name = CTL_UNNUMBERED,
288 .procname = "sched_features",
289 .data = &sysctl_sched_features,
290 .maxlen = sizeof(unsigned int),
291 .mode = 0644,
292 .proc_handler = &proc_dointvec,
295 .ctl_name = CTL_UNNUMBERED,
296 .procname = "sched_migration_cost",
297 .data = &sysctl_sched_migration_cost,
298 .maxlen = sizeof(unsigned int),
299 .mode = 0644,
300 .proc_handler = &proc_dointvec,
302 #endif
304 .ctl_name = CTL_UNNUMBERED,
305 .procname = "sched_compat_yield",
306 .data = &sysctl_sched_compat_yield,
307 .maxlen = sizeof(unsigned int),
308 .mode = 0644,
309 .proc_handler = &proc_dointvec,
311 #ifdef CONFIG_PROVE_LOCKING
313 .ctl_name = CTL_UNNUMBERED,
314 .procname = "prove_locking",
315 .data = &prove_locking,
316 .maxlen = sizeof(int),
317 .mode = 0644,
318 .proc_handler = &proc_dointvec,
320 #endif
321 #ifdef CONFIG_LOCK_STAT
323 .ctl_name = CTL_UNNUMBERED,
324 .procname = "lock_stat",
325 .data = &lock_stat,
326 .maxlen = sizeof(int),
327 .mode = 0644,
328 .proc_handler = &proc_dointvec,
330 #endif
332 .ctl_name = KERN_PANIC,
333 .procname = "panic",
334 .data = &panic_timeout,
335 .maxlen = sizeof(int),
336 .mode = 0644,
337 .proc_handler = &proc_dointvec,
340 .ctl_name = KERN_CORE_USES_PID,
341 .procname = "core_uses_pid",
342 .data = &core_uses_pid,
343 .maxlen = sizeof(int),
344 .mode = 0644,
345 .proc_handler = &proc_dointvec,
347 #ifdef CONFIG_AUDITSYSCALL
349 .ctl_name = CTL_UNNUMBERED,
350 .procname = "audit_argv_kb",
351 .data = &audit_argv_kb,
352 .maxlen = sizeof(int),
353 .mode = 0644,
354 .proc_handler = &proc_dointvec,
356 #endif
358 .ctl_name = KERN_CORE_PATTERN,
359 .procname = "core_pattern",
360 .data = core_pattern,
361 .maxlen = CORENAME_MAX_SIZE,
362 .mode = 0644,
363 .proc_handler = &proc_dostring,
364 .strategy = &sysctl_string,
366 #ifdef CONFIG_PROC_SYSCTL
368 .ctl_name = KERN_TAINTED,
369 .procname = "tainted",
370 .data = &tainted,
371 .maxlen = sizeof(int),
372 .mode = 0644,
373 .proc_handler = &proc_dointvec_taint,
375 #endif
377 .ctl_name = KERN_CAP_BSET,
378 .procname = "cap-bound",
379 .data = &cap_bset,
380 .maxlen = sizeof(kernel_cap_t),
381 .mode = 0600,
382 .proc_handler = &proc_dointvec_bset,
384 #ifdef CONFIG_BLK_DEV_INITRD
386 .ctl_name = KERN_REALROOTDEV,
387 .procname = "real-root-dev",
388 .data = &real_root_dev,
389 .maxlen = sizeof(int),
390 .mode = 0644,
391 .proc_handler = &proc_dointvec,
393 #endif
395 .ctl_name = CTL_UNNUMBERED,
396 .procname = "print-fatal-signals",
397 .data = &print_fatal_signals,
398 .maxlen = sizeof(int),
399 .mode = 0644,
400 .proc_handler = &proc_dointvec,
402 #ifdef __sparc__
404 .ctl_name = KERN_SPARC_REBOOT,
405 .procname = "reboot-cmd",
406 .data = reboot_command,
407 .maxlen = 256,
408 .mode = 0644,
409 .proc_handler = &proc_dostring,
410 .strategy = &sysctl_string,
413 .ctl_name = KERN_SPARC_STOP_A,
414 .procname = "stop-a",
415 .data = &stop_a_enabled,
416 .maxlen = sizeof (int),
417 .mode = 0644,
418 .proc_handler = &proc_dointvec,
421 .ctl_name = KERN_SPARC_SCONS_PWROFF,
422 .procname = "scons-poweroff",
423 .data = &scons_pwroff,
424 .maxlen = sizeof (int),
425 .mode = 0644,
426 .proc_handler = &proc_dointvec,
428 #endif
429 #ifdef __hppa__
431 .ctl_name = KERN_HPPA_PWRSW,
432 .procname = "soft-power",
433 .data = &pwrsw_enabled,
434 .maxlen = sizeof (int),
435 .mode = 0644,
436 .proc_handler = &proc_dointvec,
439 .ctl_name = KERN_HPPA_UNALIGNED,
440 .procname = "unaligned-trap",
441 .data = &unaligned_enabled,
442 .maxlen = sizeof (int),
443 .mode = 0644,
444 .proc_handler = &proc_dointvec,
446 #endif
448 .ctl_name = KERN_CTLALTDEL,
449 .procname = "ctrl-alt-del",
450 .data = &C_A_D,
451 .maxlen = sizeof(int),
452 .mode = 0644,
453 .proc_handler = &proc_dointvec,
456 .ctl_name = KERN_PRINTK,
457 .procname = "printk",
458 .data = &console_loglevel,
459 .maxlen = 4*sizeof(int),
460 .mode = 0644,
461 .proc_handler = &proc_dointvec,
463 #ifdef CONFIG_KMOD
465 .ctl_name = KERN_MODPROBE,
466 .procname = "modprobe",
467 .data = &modprobe_path,
468 .maxlen = KMOD_PATH_LEN,
469 .mode = 0644,
470 .proc_handler = &proc_dostring,
471 .strategy = &sysctl_string,
473 #endif
474 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
476 .ctl_name = KERN_HOTPLUG,
477 .procname = "hotplug",
478 .data = &uevent_helper,
479 .maxlen = UEVENT_HELPER_PATH_LEN,
480 .mode = 0644,
481 .proc_handler = &proc_dostring,
482 .strategy = &sysctl_string,
484 #endif
485 #ifdef CONFIG_CHR_DEV_SG
487 .ctl_name = KERN_SG_BIG_BUFF,
488 .procname = "sg-big-buff",
489 .data = &sg_big_buff,
490 .maxlen = sizeof (int),
491 .mode = 0444,
492 .proc_handler = &proc_dointvec,
494 #endif
495 #ifdef CONFIG_BSD_PROCESS_ACCT
497 .ctl_name = KERN_ACCT,
498 .procname = "acct",
499 .data = &acct_parm,
500 .maxlen = 3*sizeof(int),
501 .mode = 0644,
502 .proc_handler = &proc_dointvec,
504 #endif
505 #ifdef CONFIG_MAGIC_SYSRQ
507 .ctl_name = KERN_SYSRQ,
508 .procname = "sysrq",
509 .data = &__sysrq_enabled,
510 .maxlen = sizeof (int),
511 .mode = 0644,
512 .proc_handler = &proc_dointvec,
514 #endif
515 #ifdef CONFIG_PROC_SYSCTL
517 .ctl_name = KERN_CADPID,
518 .procname = "cad_pid",
519 .data = NULL,
520 .maxlen = sizeof (int),
521 .mode = 0600,
522 .proc_handler = &proc_do_cad_pid,
524 #endif
526 .ctl_name = KERN_MAX_THREADS,
527 .procname = "threads-max",
528 .data = &max_threads,
529 .maxlen = sizeof(int),
530 .mode = 0644,
531 .proc_handler = &proc_dointvec,
534 .ctl_name = KERN_RANDOM,
535 .procname = "random",
536 .mode = 0555,
537 .child = random_table,
539 #ifdef CONFIG_UNIX98_PTYS
541 .ctl_name = KERN_PTY,
542 .procname = "pty",
543 .mode = 0555,
544 .child = pty_table,
546 #endif
548 .ctl_name = KERN_OVERFLOWUID,
549 .procname = "overflowuid",
550 .data = &overflowuid,
551 .maxlen = sizeof(int),
552 .mode = 0644,
553 .proc_handler = &proc_dointvec_minmax,
554 .strategy = &sysctl_intvec,
555 .extra1 = &minolduid,
556 .extra2 = &maxolduid,
559 .ctl_name = KERN_OVERFLOWGID,
560 .procname = "overflowgid",
561 .data = &overflowgid,
562 .maxlen = sizeof(int),
563 .mode = 0644,
564 .proc_handler = &proc_dointvec_minmax,
565 .strategy = &sysctl_intvec,
566 .extra1 = &minolduid,
567 .extra2 = &maxolduid,
569 #ifdef CONFIG_S390
570 #ifdef CONFIG_MATHEMU
572 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
573 .procname = "ieee_emulation_warnings",
574 .data = &sysctl_ieee_emulation_warnings,
575 .maxlen = sizeof(int),
576 .mode = 0644,
577 .proc_handler = &proc_dointvec,
579 #endif
580 #ifdef CONFIG_NO_IDLE_HZ
582 .ctl_name = KERN_HZ_TIMER,
583 .procname = "hz_timer",
584 .data = &sysctl_hz_timer,
585 .maxlen = sizeof(int),
586 .mode = 0644,
587 .proc_handler = &proc_dointvec,
589 #endif
591 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
592 .procname = "userprocess_debug",
593 .data = &sysctl_userprocess_debug,
594 .maxlen = sizeof(int),
595 .mode = 0644,
596 .proc_handler = &proc_dointvec,
598 #endif
600 .ctl_name = KERN_PIDMAX,
601 .procname = "pid_max",
602 .data = &pid_max,
603 .maxlen = sizeof (int),
604 .mode = 0644,
605 .proc_handler = &proc_dointvec_minmax,
606 .strategy = sysctl_intvec,
607 .extra1 = &pid_max_min,
608 .extra2 = &pid_max_max,
611 .ctl_name = KERN_PANIC_ON_OOPS,
612 .procname = "panic_on_oops",
613 .data = &panic_on_oops,
614 .maxlen = sizeof(int),
615 .mode = 0644,
616 .proc_handler = &proc_dointvec,
619 .ctl_name = KERN_PRINTK_RATELIMIT,
620 .procname = "printk_ratelimit",
621 .data = &printk_ratelimit_jiffies,
622 .maxlen = sizeof(int),
623 .mode = 0644,
624 .proc_handler = &proc_dointvec_jiffies,
625 .strategy = &sysctl_jiffies,
628 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
629 .procname = "printk_ratelimit_burst",
630 .data = &printk_ratelimit_burst,
631 .maxlen = sizeof(int),
632 .mode = 0644,
633 .proc_handler = &proc_dointvec,
636 .ctl_name = KERN_NGROUPS_MAX,
637 .procname = "ngroups_max",
638 .data = &ngroups_max,
639 .maxlen = sizeof (int),
640 .mode = 0444,
641 .proc_handler = &proc_dointvec,
643 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
645 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
646 .procname = "unknown_nmi_panic",
647 .data = &unknown_nmi_panic,
648 .maxlen = sizeof (int),
649 .mode = 0644,
650 .proc_handler = &proc_dointvec,
653 .ctl_name = KERN_NMI_WATCHDOG,
654 .procname = "nmi_watchdog",
655 .data = &nmi_watchdog_enabled,
656 .maxlen = sizeof (int),
657 .mode = 0644,
658 .proc_handler = &proc_nmi_enabled,
660 #endif
661 #if defined(CONFIG_X86)
663 .ctl_name = KERN_PANIC_ON_NMI,
664 .procname = "panic_on_unrecovered_nmi",
665 .data = &panic_on_unrecovered_nmi,
666 .maxlen = sizeof(int),
667 .mode = 0644,
668 .proc_handler = &proc_dointvec,
671 .ctl_name = KERN_BOOTLOADER_TYPE,
672 .procname = "bootloader_type",
673 .data = &bootloader_type,
674 .maxlen = sizeof (int),
675 .mode = 0444,
676 .proc_handler = &proc_dointvec,
679 .ctl_name = CTL_UNNUMBERED,
680 .procname = "kstack_depth_to_print",
681 .data = &kstack_depth_to_print,
682 .maxlen = sizeof(int),
683 .mode = 0644,
684 .proc_handler = &proc_dointvec,
686 #endif
687 #if defined(CONFIG_MMU)
689 .ctl_name = KERN_RANDOMIZE,
690 .procname = "randomize_va_space",
691 .data = &randomize_va_space,
692 .maxlen = sizeof(int),
693 .mode = 0644,
694 .proc_handler = &proc_dointvec,
696 #endif
697 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
699 .ctl_name = KERN_SPIN_RETRY,
700 .procname = "spin_retry",
701 .data = &spin_retry,
702 .maxlen = sizeof (int),
703 .mode = 0644,
704 .proc_handler = &proc_dointvec,
706 #endif
707 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
709 .ctl_name = KERN_ACPI_VIDEO_FLAGS,
710 .procname = "acpi_video_flags",
711 .data = &acpi_realmode_flags,
712 .maxlen = sizeof (unsigned long),
713 .mode = 0644,
714 .proc_handler = &proc_doulongvec_minmax,
716 #endif
717 #ifdef CONFIG_IA64
719 .ctl_name = KERN_IA64_UNALIGNED,
720 .procname = "ignore-unaligned-usertrap",
721 .data = &no_unaligned_warning,
722 .maxlen = sizeof (int),
723 .mode = 0644,
724 .proc_handler = &proc_dointvec,
726 #endif
727 #ifdef CONFIG_DETECT_SOFTLOCKUP
729 .ctl_name = CTL_UNNUMBERED,
730 .procname = "softlockup_thresh",
731 .data = &softlockup_thresh,
732 .maxlen = sizeof(int),
733 .mode = 0644,
734 .proc_handler = &proc_dointvec_minmax,
735 .strategy = &sysctl_intvec,
736 .extra1 = &one,
737 .extra2 = &sixty,
739 #endif
740 #ifdef CONFIG_COMPAT
742 .ctl_name = KERN_COMPAT_LOG,
743 .procname = "compat-log",
744 .data = &compat_log,
745 .maxlen = sizeof (int),
746 .mode = 0644,
747 .proc_handler = &proc_dointvec,
749 #endif
750 #ifdef CONFIG_RT_MUTEXES
752 .ctl_name = KERN_MAX_LOCK_DEPTH,
753 .procname = "max_lock_depth",
754 .data = &max_lock_depth,
755 .maxlen = sizeof(int),
756 .mode = 0644,
757 .proc_handler = &proc_dointvec,
759 #endif
760 #ifdef CONFIG_PROC_FS
762 .ctl_name = CTL_UNNUMBERED,
763 .procname = "maps_protect",
764 .data = &maps_protect,
765 .maxlen = sizeof(int),
766 .mode = 0644,
767 .proc_handler = &proc_dointvec,
769 #endif
771 .ctl_name = CTL_UNNUMBERED,
772 .procname = "poweroff_cmd",
773 .data = &poweroff_cmd,
774 .maxlen = POWEROFF_CMD_PATH_LEN,
775 .mode = 0644,
776 .proc_handler = &proc_dostring,
777 .strategy = &sysctl_string,
780 * NOTE: do not add new entries to this table unless you have read
781 * Documentation/sysctl/ctl_unnumbered.txt
783 { .ctl_name = 0 }
786 static struct ctl_table vm_table[] = {
788 .ctl_name = VM_OVERCOMMIT_MEMORY,
789 .procname = "overcommit_memory",
790 .data = &sysctl_overcommit_memory,
791 .maxlen = sizeof(sysctl_overcommit_memory),
792 .mode = 0644,
793 .proc_handler = &proc_dointvec,
796 .ctl_name = VM_PANIC_ON_OOM,
797 .procname = "panic_on_oom",
798 .data = &sysctl_panic_on_oom,
799 .maxlen = sizeof(sysctl_panic_on_oom),
800 .mode = 0644,
801 .proc_handler = &proc_dointvec,
804 .ctl_name = CTL_UNNUMBERED,
805 .procname = "oom_kill_allocating_task",
806 .data = &sysctl_oom_kill_allocating_task,
807 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
808 .mode = 0644,
809 .proc_handler = &proc_dointvec,
812 .ctl_name = VM_OVERCOMMIT_RATIO,
813 .procname = "overcommit_ratio",
814 .data = &sysctl_overcommit_ratio,
815 .maxlen = sizeof(sysctl_overcommit_ratio),
816 .mode = 0644,
817 .proc_handler = &proc_dointvec,
820 .ctl_name = VM_PAGE_CLUSTER,
821 .procname = "page-cluster",
822 .data = &page_cluster,
823 .maxlen = sizeof(int),
824 .mode = 0644,
825 .proc_handler = &proc_dointvec,
828 .ctl_name = VM_DIRTY_BACKGROUND,
829 .procname = "dirty_background_ratio",
830 .data = &dirty_background_ratio,
831 .maxlen = sizeof(dirty_background_ratio),
832 .mode = 0644,
833 .proc_handler = &proc_dointvec_minmax,
834 .strategy = &sysctl_intvec,
835 .extra1 = &zero,
836 .extra2 = &one_hundred,
839 .ctl_name = VM_DIRTY_RATIO,
840 .procname = "dirty_ratio",
841 .data = &vm_dirty_ratio,
842 .maxlen = sizeof(vm_dirty_ratio),
843 .mode = 0644,
844 .proc_handler = &dirty_ratio_handler,
845 .strategy = &sysctl_intvec,
846 .extra1 = &zero,
847 .extra2 = &one_hundred,
850 .ctl_name = VM_DIRTY_WB_CS,
851 .procname = "dirty_writeback_centisecs",
852 .data = &dirty_writeback_interval,
853 .maxlen = sizeof(dirty_writeback_interval),
854 .mode = 0644,
855 .proc_handler = &dirty_writeback_centisecs_handler,
858 .ctl_name = VM_DIRTY_EXPIRE_CS,
859 .procname = "dirty_expire_centisecs",
860 .data = &dirty_expire_interval,
861 .maxlen = sizeof(dirty_expire_interval),
862 .mode = 0644,
863 .proc_handler = &proc_dointvec_userhz_jiffies,
866 .ctl_name = VM_NR_PDFLUSH_THREADS,
867 .procname = "nr_pdflush_threads",
868 .data = &nr_pdflush_threads,
869 .maxlen = sizeof nr_pdflush_threads,
870 .mode = 0444 /* read-only*/,
871 .proc_handler = &proc_dointvec,
874 .ctl_name = VM_SWAPPINESS,
875 .procname = "swappiness",
876 .data = &vm_swappiness,
877 .maxlen = sizeof(vm_swappiness),
878 .mode = 0644,
879 .proc_handler = &proc_dointvec_minmax,
880 .strategy = &sysctl_intvec,
881 .extra1 = &zero,
882 .extra2 = &one_hundred,
884 #ifdef CONFIG_HUGETLB_PAGE
886 .ctl_name = VM_HUGETLB_PAGES,
887 .procname = "nr_hugepages",
888 .data = &max_huge_pages,
889 .maxlen = sizeof(unsigned long),
890 .mode = 0644,
891 .proc_handler = &hugetlb_sysctl_handler,
892 .extra1 = (void *)&hugetlb_zero,
893 .extra2 = (void *)&hugetlb_infinity,
896 .ctl_name = VM_HUGETLB_GROUP,
897 .procname = "hugetlb_shm_group",
898 .data = &sysctl_hugetlb_shm_group,
899 .maxlen = sizeof(gid_t),
900 .mode = 0644,
901 .proc_handler = &proc_dointvec,
904 .ctl_name = CTL_UNNUMBERED,
905 .procname = "hugepages_treat_as_movable",
906 .data = &hugepages_treat_as_movable,
907 .maxlen = sizeof(int),
908 .mode = 0644,
909 .proc_handler = &hugetlb_treat_movable_handler,
912 .ctl_name = CTL_UNNUMBERED,
913 .procname = "hugetlb_dynamic_pool",
914 .data = &hugetlb_dynamic_pool,
915 .maxlen = sizeof(hugetlb_dynamic_pool),
916 .mode = 0644,
917 .proc_handler = &proc_dointvec,
919 #endif
921 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
922 .procname = "lowmem_reserve_ratio",
923 .data = &sysctl_lowmem_reserve_ratio,
924 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
925 .mode = 0644,
926 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
927 .strategy = &sysctl_intvec,
930 .ctl_name = VM_DROP_PAGECACHE,
931 .procname = "drop_caches",
932 .data = &sysctl_drop_caches,
933 .maxlen = sizeof(int),
934 .mode = 0644,
935 .proc_handler = drop_caches_sysctl_handler,
936 .strategy = &sysctl_intvec,
939 .ctl_name = VM_MIN_FREE_KBYTES,
940 .procname = "min_free_kbytes",
941 .data = &min_free_kbytes,
942 .maxlen = sizeof(min_free_kbytes),
943 .mode = 0644,
944 .proc_handler = &min_free_kbytes_sysctl_handler,
945 .strategy = &sysctl_intvec,
946 .extra1 = &zero,
949 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
950 .procname = "percpu_pagelist_fraction",
951 .data = &percpu_pagelist_fraction,
952 .maxlen = sizeof(percpu_pagelist_fraction),
953 .mode = 0644,
954 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
955 .strategy = &sysctl_intvec,
956 .extra1 = &min_percpu_pagelist_fract,
958 #ifdef CONFIG_MMU
960 .ctl_name = VM_MAX_MAP_COUNT,
961 .procname = "max_map_count",
962 .data = &sysctl_max_map_count,
963 .maxlen = sizeof(sysctl_max_map_count),
964 .mode = 0644,
965 .proc_handler = &proc_dointvec
967 #endif
969 .ctl_name = VM_LAPTOP_MODE,
970 .procname = "laptop_mode",
971 .data = &laptop_mode,
972 .maxlen = sizeof(laptop_mode),
973 .mode = 0644,
974 .proc_handler = &proc_dointvec_jiffies,
975 .strategy = &sysctl_jiffies,
978 .ctl_name = VM_BLOCK_DUMP,
979 .procname = "block_dump",
980 .data = &block_dump,
981 .maxlen = sizeof(block_dump),
982 .mode = 0644,
983 .proc_handler = &proc_dointvec,
984 .strategy = &sysctl_intvec,
985 .extra1 = &zero,
988 .ctl_name = VM_VFS_CACHE_PRESSURE,
989 .procname = "vfs_cache_pressure",
990 .data = &sysctl_vfs_cache_pressure,
991 .maxlen = sizeof(sysctl_vfs_cache_pressure),
992 .mode = 0644,
993 .proc_handler = &proc_dointvec,
994 .strategy = &sysctl_intvec,
995 .extra1 = &zero,
997 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
999 .ctl_name = VM_LEGACY_VA_LAYOUT,
1000 .procname = "legacy_va_layout",
1001 .data = &sysctl_legacy_va_layout,
1002 .maxlen = sizeof(sysctl_legacy_va_layout),
1003 .mode = 0644,
1004 .proc_handler = &proc_dointvec,
1005 .strategy = &sysctl_intvec,
1006 .extra1 = &zero,
1008 #endif
1009 #ifdef CONFIG_NUMA
1011 .ctl_name = VM_ZONE_RECLAIM_MODE,
1012 .procname = "zone_reclaim_mode",
1013 .data = &zone_reclaim_mode,
1014 .maxlen = sizeof(zone_reclaim_mode),
1015 .mode = 0644,
1016 .proc_handler = &proc_dointvec,
1017 .strategy = &sysctl_intvec,
1018 .extra1 = &zero,
1021 .ctl_name = VM_MIN_UNMAPPED,
1022 .procname = "min_unmapped_ratio",
1023 .data = &sysctl_min_unmapped_ratio,
1024 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1025 .mode = 0644,
1026 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
1027 .strategy = &sysctl_intvec,
1028 .extra1 = &zero,
1029 .extra2 = &one_hundred,
1032 .ctl_name = VM_MIN_SLAB,
1033 .procname = "min_slab_ratio",
1034 .data = &sysctl_min_slab_ratio,
1035 .maxlen = sizeof(sysctl_min_slab_ratio),
1036 .mode = 0644,
1037 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler,
1038 .strategy = &sysctl_intvec,
1039 .extra1 = &zero,
1040 .extra2 = &one_hundred,
1042 #endif
1043 #ifdef CONFIG_SMP
1045 .ctl_name = CTL_UNNUMBERED,
1046 .procname = "stat_interval",
1047 .data = &sysctl_stat_interval,
1048 .maxlen = sizeof(sysctl_stat_interval),
1049 .mode = 0644,
1050 .proc_handler = &proc_dointvec_jiffies,
1051 .strategy = &sysctl_jiffies,
1053 #endif
1054 #ifdef CONFIG_SECURITY
1056 .ctl_name = CTL_UNNUMBERED,
1057 .procname = "mmap_min_addr",
1058 .data = &mmap_min_addr,
1059 .maxlen = sizeof(unsigned long),
1060 .mode = 0644,
1061 .proc_handler = &proc_doulongvec_minmax,
1063 #endif
1064 #ifdef CONFIG_NUMA
1066 .ctl_name = CTL_UNNUMBERED,
1067 .procname = "numa_zonelist_order",
1068 .data = &numa_zonelist_order,
1069 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1070 .mode = 0644,
1071 .proc_handler = &numa_zonelist_order_handler,
1072 .strategy = &sysctl_string,
1074 #endif
1075 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1076 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1078 .ctl_name = VM_VDSO_ENABLED,
1079 .procname = "vdso_enabled",
1080 .data = &vdso_enabled,
1081 .maxlen = sizeof(vdso_enabled),
1082 .mode = 0644,
1083 .proc_handler = &proc_dointvec,
1084 .strategy = &sysctl_intvec,
1085 .extra1 = &zero,
1087 #endif
1089 * NOTE: do not add new entries to this table unless you have read
1090 * Documentation/sysctl/ctl_unnumbered.txt
1092 { .ctl_name = 0 }
1095 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1096 static struct ctl_table binfmt_misc_table[] = {
1097 { .ctl_name = 0 }
1099 #endif
1101 static struct ctl_table fs_table[] = {
1103 .ctl_name = FS_NRINODE,
1104 .procname = "inode-nr",
1105 .data = &inodes_stat,
1106 .maxlen = 2*sizeof(int),
1107 .mode = 0444,
1108 .proc_handler = &proc_dointvec,
1111 .ctl_name = FS_STATINODE,
1112 .procname = "inode-state",
1113 .data = &inodes_stat,
1114 .maxlen = 7*sizeof(int),
1115 .mode = 0444,
1116 .proc_handler = &proc_dointvec,
1119 .ctl_name = FS_NRFILE,
1120 .procname = "file-nr",
1121 .data = &files_stat,
1122 .maxlen = 3*sizeof(int),
1123 .mode = 0444,
1124 .proc_handler = &proc_nr_files,
1127 .ctl_name = FS_MAXFILE,
1128 .procname = "file-max",
1129 .data = &files_stat.max_files,
1130 .maxlen = sizeof(int),
1131 .mode = 0644,
1132 .proc_handler = &proc_dointvec,
1135 .ctl_name = FS_DENTRY,
1136 .procname = "dentry-state",
1137 .data = &dentry_stat,
1138 .maxlen = 6*sizeof(int),
1139 .mode = 0444,
1140 .proc_handler = &proc_dointvec,
1143 .ctl_name = FS_OVERFLOWUID,
1144 .procname = "overflowuid",
1145 .data = &fs_overflowuid,
1146 .maxlen = sizeof(int),
1147 .mode = 0644,
1148 .proc_handler = &proc_dointvec_minmax,
1149 .strategy = &sysctl_intvec,
1150 .extra1 = &minolduid,
1151 .extra2 = &maxolduid,
1154 .ctl_name = FS_OVERFLOWGID,
1155 .procname = "overflowgid",
1156 .data = &fs_overflowgid,
1157 .maxlen = sizeof(int),
1158 .mode = 0644,
1159 .proc_handler = &proc_dointvec_minmax,
1160 .strategy = &sysctl_intvec,
1161 .extra1 = &minolduid,
1162 .extra2 = &maxolduid,
1165 .ctl_name = FS_LEASES,
1166 .procname = "leases-enable",
1167 .data = &leases_enable,
1168 .maxlen = sizeof(int),
1169 .mode = 0644,
1170 .proc_handler = &proc_dointvec,
1172 #ifdef CONFIG_DNOTIFY
1174 .ctl_name = FS_DIR_NOTIFY,
1175 .procname = "dir-notify-enable",
1176 .data = &dir_notify_enable,
1177 .maxlen = sizeof(int),
1178 .mode = 0644,
1179 .proc_handler = &proc_dointvec,
1181 #endif
1182 #ifdef CONFIG_MMU
1184 .ctl_name = FS_LEASE_TIME,
1185 .procname = "lease-break-time",
1186 .data = &lease_break_time,
1187 .maxlen = sizeof(int),
1188 .mode = 0644,
1189 .proc_handler = &proc_dointvec_minmax,
1190 .strategy = &sysctl_intvec,
1191 .extra1 = &zero,
1192 .extra2 = &two,
1195 .ctl_name = FS_AIO_NR,
1196 .procname = "aio-nr",
1197 .data = &aio_nr,
1198 .maxlen = sizeof(aio_nr),
1199 .mode = 0444,
1200 .proc_handler = &proc_doulongvec_minmax,
1203 .ctl_name = FS_AIO_MAX_NR,
1204 .procname = "aio-max-nr",
1205 .data = &aio_max_nr,
1206 .maxlen = sizeof(aio_max_nr),
1207 .mode = 0644,
1208 .proc_handler = &proc_doulongvec_minmax,
1210 #ifdef CONFIG_INOTIFY_USER
1212 .ctl_name = FS_INOTIFY,
1213 .procname = "inotify",
1214 .mode = 0555,
1215 .child = inotify_table,
1217 #endif
1218 #endif
1220 .ctl_name = KERN_SETUID_DUMPABLE,
1221 .procname = "suid_dumpable",
1222 .data = &suid_dumpable,
1223 .maxlen = sizeof(int),
1224 .mode = 0644,
1225 .proc_handler = &proc_dointvec,
1227 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1229 .ctl_name = CTL_UNNUMBERED,
1230 .procname = "binfmt_misc",
1231 .mode = 0555,
1232 .child = binfmt_misc_table,
1234 #endif
1236 * NOTE: do not add new entries to this table unless you have read
1237 * Documentation/sysctl/ctl_unnumbered.txt
1239 { .ctl_name = 0 }
1242 static struct ctl_table debug_table[] = {
1243 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1245 .ctl_name = CTL_UNNUMBERED,
1246 .procname = "exception-trace",
1247 .data = &show_unhandled_signals,
1248 .maxlen = sizeof(int),
1249 .mode = 0644,
1250 .proc_handler = proc_dointvec
1252 #endif
1253 { .ctl_name = 0 }
1256 static struct ctl_table dev_table[] = {
1257 { .ctl_name = 0 }
1260 static DEFINE_SPINLOCK(sysctl_lock);
1262 /* called under sysctl_lock */
1263 static int use_table(struct ctl_table_header *p)
1265 if (unlikely(p->unregistering))
1266 return 0;
1267 p->used++;
1268 return 1;
1271 /* called under sysctl_lock */
1272 static void unuse_table(struct ctl_table_header *p)
1274 if (!--p->used)
1275 if (unlikely(p->unregistering))
1276 complete(p->unregistering);
1279 /* called under sysctl_lock, will reacquire if has to wait */
1280 static void start_unregistering(struct ctl_table_header *p)
1283 * if p->used is 0, nobody will ever touch that entry again;
1284 * we'll eliminate all paths to it before dropping sysctl_lock
1286 if (unlikely(p->used)) {
1287 struct completion wait;
1288 init_completion(&wait);
1289 p->unregistering = &wait;
1290 spin_unlock(&sysctl_lock);
1291 wait_for_completion(&wait);
1292 spin_lock(&sysctl_lock);
1295 * do not remove from the list until nobody holds it; walking the
1296 * list in do_sysctl() relies on that.
1298 list_del_init(&p->ctl_entry);
1301 void sysctl_head_finish(struct ctl_table_header *head)
1303 if (!head)
1304 return;
1305 spin_lock(&sysctl_lock);
1306 unuse_table(head);
1307 spin_unlock(&sysctl_lock);
1310 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1312 struct ctl_table_header *head;
1313 struct list_head *tmp;
1314 spin_lock(&sysctl_lock);
1315 if (prev) {
1316 tmp = &prev->ctl_entry;
1317 unuse_table(prev);
1318 goto next;
1320 tmp = &root_table_header.ctl_entry;
1321 for (;;) {
1322 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1324 if (!use_table(head))
1325 goto next;
1326 spin_unlock(&sysctl_lock);
1327 return head;
1328 next:
1329 tmp = tmp->next;
1330 if (tmp == &root_table_header.ctl_entry)
1331 break;
1333 spin_unlock(&sysctl_lock);
1334 return NULL;
1337 #ifdef CONFIG_SYSCTL_SYSCALL
1338 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1339 void __user *newval, size_t newlen)
1341 struct ctl_table_header *head;
1342 int error = -ENOTDIR;
1344 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1345 return -ENOTDIR;
1346 if (oldval) {
1347 int old_len;
1348 if (!oldlenp || get_user(old_len, oldlenp))
1349 return -EFAULT;
1352 for (head = sysctl_head_next(NULL); head;
1353 head = sysctl_head_next(head)) {
1354 error = parse_table(name, nlen, oldval, oldlenp,
1355 newval, newlen, head->ctl_table);
1356 if (error != -ENOTDIR) {
1357 sysctl_head_finish(head);
1358 break;
1361 return error;
1364 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1366 struct __sysctl_args tmp;
1367 int error;
1369 if (copy_from_user(&tmp, args, sizeof(tmp)))
1370 return -EFAULT;
1372 lock_kernel();
1373 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1374 tmp.newval, tmp.newlen);
1375 unlock_kernel();
1376 return error;
1378 #endif /* CONFIG_SYSCTL_SYSCALL */
1381 * sysctl_perm does NOT grant the superuser all rights automatically, because
1382 * some sysctl variables are readonly even to root.
1385 static int test_perm(int mode, int op)
1387 if (!current->euid)
1388 mode >>= 6;
1389 else if (in_egroup_p(0))
1390 mode >>= 3;
1391 if ((mode & op & 0007) == op)
1392 return 0;
1393 return -EACCES;
1396 int sysctl_perm(struct ctl_table *table, int op)
1398 int error;
1399 error = security_sysctl(table, op);
1400 if (error)
1401 return error;
1402 return test_perm(table->mode, op);
1405 #ifdef CONFIG_SYSCTL_SYSCALL
1406 static int parse_table(int __user *name, int nlen,
1407 void __user *oldval, size_t __user *oldlenp,
1408 void __user *newval, size_t newlen,
1409 struct ctl_table *table)
1411 int n;
1412 repeat:
1413 if (!nlen)
1414 return -ENOTDIR;
1415 if (get_user(n, name))
1416 return -EFAULT;
1417 for ( ; table->ctl_name || table->procname; table++) {
1418 if (!table->ctl_name)
1419 continue;
1420 if (n == table->ctl_name) {
1421 int error;
1422 if (table->child) {
1423 if (sysctl_perm(table, 001))
1424 return -EPERM;
1425 name++;
1426 nlen--;
1427 table = table->child;
1428 goto repeat;
1430 error = do_sysctl_strategy(table, name, nlen,
1431 oldval, oldlenp,
1432 newval, newlen);
1433 return error;
1436 return -ENOTDIR;
1439 /* Perform the actual read/write of a sysctl table entry. */
1440 int do_sysctl_strategy (struct ctl_table *table,
1441 int __user *name, int nlen,
1442 void __user *oldval, size_t __user *oldlenp,
1443 void __user *newval, size_t newlen)
1445 int op = 0, rc;
1447 if (oldval)
1448 op |= 004;
1449 if (newval)
1450 op |= 002;
1451 if (sysctl_perm(table, op))
1452 return -EPERM;
1454 if (table->strategy) {
1455 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1456 newval, newlen);
1457 if (rc < 0)
1458 return rc;
1459 if (rc > 0)
1460 return 0;
1463 /* If there is no strategy routine, or if the strategy returns
1464 * zero, proceed with automatic r/w */
1465 if (table->data && table->maxlen) {
1466 rc = sysctl_data(table, name, nlen, oldval, oldlenp,
1467 newval, newlen);
1468 if (rc < 0)
1469 return rc;
1471 return 0;
1473 #endif /* CONFIG_SYSCTL_SYSCALL */
1475 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1477 for (; table->ctl_name || table->procname; table++) {
1478 table->parent = parent;
1479 if (table->child)
1480 sysctl_set_parent(table, table->child);
1484 static __init int sysctl_init(void)
1486 sysctl_set_parent(NULL, root_table);
1487 return 0;
1490 core_initcall(sysctl_init);
1493 * register_sysctl_table - register a sysctl hierarchy
1494 * @table: the top-level table structure
1496 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1497 * array. An entry with a ctl_name of 0 terminates the table.
1499 * The members of the &struct ctl_table structure are used as follows:
1501 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1502 * must be unique within that level of sysctl
1504 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1505 * enter a sysctl file
1507 * data - a pointer to data for use by proc_handler
1509 * maxlen - the maximum size in bytes of the data
1511 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1513 * child - a pointer to the child sysctl table if this entry is a directory, or
1514 * %NULL.
1516 * proc_handler - the text handler routine (described below)
1518 * strategy - the strategy routine (described below)
1520 * de - for internal use by the sysctl routines
1522 * extra1, extra2 - extra pointers usable by the proc handler routines
1524 * Leaf nodes in the sysctl tree will be represented by a single file
1525 * under /proc; non-leaf nodes will be represented by directories.
1527 * sysctl(2) can automatically manage read and write requests through
1528 * the sysctl table. The data and maxlen fields of the ctl_table
1529 * struct enable minimal validation of the values being written to be
1530 * performed, and the mode field allows minimal authentication.
1532 * More sophisticated management can be enabled by the provision of a
1533 * strategy routine with the table entry. This will be called before
1534 * any automatic read or write of the data is performed.
1536 * The strategy routine may return
1538 * < 0 - Error occurred (error is passed to user process)
1540 * 0 - OK - proceed with automatic read or write.
1542 * > 0 - OK - read or write has been done by the strategy routine, so
1543 * return immediately.
1545 * There must be a proc_handler routine for any terminal nodes
1546 * mirrored under /proc/sys (non-terminals are handled by a built-in
1547 * directory handler). Several default handlers are available to
1548 * cover common cases -
1550 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1551 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1552 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1554 * It is the handler's job to read the input buffer from user memory
1555 * and process it. The handler should return 0 on success.
1557 * This routine returns %NULL on a failure to register, and a pointer
1558 * to the table header on success.
1560 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
1562 struct ctl_table_header *tmp;
1563 tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1564 if (!tmp)
1565 return NULL;
1566 tmp->ctl_table = table;
1567 INIT_LIST_HEAD(&tmp->ctl_entry);
1568 tmp->used = 0;
1569 tmp->unregistering = NULL;
1570 sysctl_set_parent(NULL, table);
1571 spin_lock(&sysctl_lock);
1572 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1573 spin_unlock(&sysctl_lock);
1574 return tmp;
1578 * unregister_sysctl_table - unregister a sysctl table hierarchy
1579 * @header: the header returned from register_sysctl_table
1581 * Unregisters the sysctl table and all children. proc entries may not
1582 * actually be removed until they are no longer used by anyone.
1584 void unregister_sysctl_table(struct ctl_table_header * header)
1586 might_sleep();
1587 spin_lock(&sysctl_lock);
1588 start_unregistering(header);
1589 spin_unlock(&sysctl_lock);
1590 kfree(header);
1593 #else /* !CONFIG_SYSCTL */
1594 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
1596 return NULL;
1599 void unregister_sysctl_table(struct ctl_table_header * table)
1603 #endif /* CONFIG_SYSCTL */
1606 * /proc/sys support
1609 #ifdef CONFIG_PROC_SYSCTL
1611 static int _proc_do_string(void* data, int maxlen, int write,
1612 struct file *filp, void __user *buffer,
1613 size_t *lenp, loff_t *ppos)
1615 size_t len;
1616 char __user *p;
1617 char c;
1619 if (!data || !maxlen || !*lenp) {
1620 *lenp = 0;
1621 return 0;
1624 if (write) {
1625 len = 0;
1626 p = buffer;
1627 while (len < *lenp) {
1628 if (get_user(c, p++))
1629 return -EFAULT;
1630 if (c == 0 || c == '\n')
1631 break;
1632 len++;
1634 if (len >= maxlen)
1635 len = maxlen-1;
1636 if(copy_from_user(data, buffer, len))
1637 return -EFAULT;
1638 ((char *) data)[len] = 0;
1639 *ppos += *lenp;
1640 } else {
1641 len = strlen(data);
1642 if (len > maxlen)
1643 len = maxlen;
1645 if (*ppos > len) {
1646 *lenp = 0;
1647 return 0;
1650 data += *ppos;
1651 len -= *ppos;
1653 if (len > *lenp)
1654 len = *lenp;
1655 if (len)
1656 if(copy_to_user(buffer, data, len))
1657 return -EFAULT;
1658 if (len < *lenp) {
1659 if(put_user('\n', ((char __user *) buffer) + len))
1660 return -EFAULT;
1661 len++;
1663 *lenp = len;
1664 *ppos += len;
1666 return 0;
1670 * proc_dostring - read a string sysctl
1671 * @table: the sysctl table
1672 * @write: %TRUE if this is a write to the sysctl file
1673 * @filp: the file structure
1674 * @buffer: the user buffer
1675 * @lenp: the size of the user buffer
1676 * @ppos: file position
1678 * Reads/writes a string from/to the user buffer. If the kernel
1679 * buffer provided is not large enough to hold the string, the
1680 * string is truncated. The copied string is %NULL-terminated.
1681 * If the string is being read by the user process, it is copied
1682 * and a newline '\n' is added. It is truncated if the buffer is
1683 * not large enough.
1685 * Returns 0 on success.
1687 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
1688 void __user *buffer, size_t *lenp, loff_t *ppos)
1690 return _proc_do_string(table->data, table->maxlen, write, filp,
1691 buffer, lenp, ppos);
1695 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1696 int *valp,
1697 int write, void *data)
1699 if (write) {
1700 *valp = *negp ? -*lvalp : *lvalp;
1701 } else {
1702 int val = *valp;
1703 if (val < 0) {
1704 *negp = -1;
1705 *lvalp = (unsigned long)-val;
1706 } else {
1707 *negp = 0;
1708 *lvalp = (unsigned long)val;
1711 return 0;
1714 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
1715 int write, struct file *filp, void __user *buffer,
1716 size_t *lenp, loff_t *ppos,
1717 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1718 int write, void *data),
1719 void *data)
1721 #define TMPBUFLEN 21
1722 int *i, vleft, first=1, neg, val;
1723 unsigned long lval;
1724 size_t left, len;
1726 char buf[TMPBUFLEN], *p;
1727 char __user *s = buffer;
1729 if (!tbl_data || !table->maxlen || !*lenp ||
1730 (*ppos && !write)) {
1731 *lenp = 0;
1732 return 0;
1735 i = (int *) tbl_data;
1736 vleft = table->maxlen / sizeof(*i);
1737 left = *lenp;
1739 if (!conv)
1740 conv = do_proc_dointvec_conv;
1742 for (; left && vleft--; i++, first=0) {
1743 if (write) {
1744 while (left) {
1745 char c;
1746 if (get_user(c, s))
1747 return -EFAULT;
1748 if (!isspace(c))
1749 break;
1750 left--;
1751 s++;
1753 if (!left)
1754 break;
1755 neg = 0;
1756 len = left;
1757 if (len > sizeof(buf) - 1)
1758 len = sizeof(buf) - 1;
1759 if (copy_from_user(buf, s, len))
1760 return -EFAULT;
1761 buf[len] = 0;
1762 p = buf;
1763 if (*p == '-' && left > 1) {
1764 neg = 1;
1765 p++;
1767 if (*p < '0' || *p > '9')
1768 break;
1770 lval = simple_strtoul(p, &p, 0);
1772 len = p-buf;
1773 if ((len < left) && *p && !isspace(*p))
1774 break;
1775 if (neg)
1776 val = -val;
1777 s += len;
1778 left -= len;
1780 if (conv(&neg, &lval, i, 1, data))
1781 break;
1782 } else {
1783 p = buf;
1784 if (!first)
1785 *p++ = '\t';
1787 if (conv(&neg, &lval, i, 0, data))
1788 break;
1790 sprintf(p, "%s%lu", neg ? "-" : "", lval);
1791 len = strlen(buf);
1792 if (len > left)
1793 len = left;
1794 if(copy_to_user(s, buf, len))
1795 return -EFAULT;
1796 left -= len;
1797 s += len;
1801 if (!write && !first && left) {
1802 if(put_user('\n', s))
1803 return -EFAULT;
1804 left--, s++;
1806 if (write) {
1807 while (left) {
1808 char c;
1809 if (get_user(c, s++))
1810 return -EFAULT;
1811 if (!isspace(c))
1812 break;
1813 left--;
1816 if (write && first)
1817 return -EINVAL;
1818 *lenp -= left;
1819 *ppos += *lenp;
1820 return 0;
1821 #undef TMPBUFLEN
1824 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
1825 void __user *buffer, size_t *lenp, loff_t *ppos,
1826 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1827 int write, void *data),
1828 void *data)
1830 return __do_proc_dointvec(table->data, table, write, filp,
1831 buffer, lenp, ppos, conv, data);
1835 * proc_dointvec - read a vector of integers
1836 * @table: the sysctl table
1837 * @write: %TRUE if this is a write to the sysctl file
1838 * @filp: the file structure
1839 * @buffer: the user buffer
1840 * @lenp: the size of the user buffer
1841 * @ppos: file position
1843 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1844 * values from/to the user buffer, treated as an ASCII string.
1846 * Returns 0 on success.
1848 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
1849 void __user *buffer, size_t *lenp, loff_t *ppos)
1851 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1852 NULL,NULL);
1855 #define OP_SET 0
1856 #define OP_AND 1
1857 #define OP_OR 2
1859 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1860 int *valp,
1861 int write, void *data)
1863 int op = *(int *)data;
1864 if (write) {
1865 int val = *negp ? -*lvalp : *lvalp;
1866 switch(op) {
1867 case OP_SET: *valp = val; break;
1868 case OP_AND: *valp &= val; break;
1869 case OP_OR: *valp |= val; break;
1871 } else {
1872 int val = *valp;
1873 if (val < 0) {
1874 *negp = -1;
1875 *lvalp = (unsigned long)-val;
1876 } else {
1877 *negp = 0;
1878 *lvalp = (unsigned long)val;
1881 return 0;
1885 * init may raise the set.
1888 int proc_dointvec_bset(struct ctl_table *table, int write, struct file *filp,
1889 void __user *buffer, size_t *lenp, loff_t *ppos)
1891 int op;
1893 if (write && !capable(CAP_SYS_MODULE)) {
1894 return -EPERM;
1897 op = is_init(current) ? OP_SET : OP_AND;
1898 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1899 do_proc_dointvec_bset_conv,&op);
1903 * Taint values can only be increased
1905 static int proc_dointvec_taint(struct ctl_table *table, int write, struct file *filp,
1906 void __user *buffer, size_t *lenp, loff_t *ppos)
1908 int op;
1910 if (write && !capable(CAP_SYS_ADMIN))
1911 return -EPERM;
1913 op = OP_OR;
1914 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1915 do_proc_dointvec_bset_conv,&op);
1918 struct do_proc_dointvec_minmax_conv_param {
1919 int *min;
1920 int *max;
1923 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1924 int *valp,
1925 int write, void *data)
1927 struct do_proc_dointvec_minmax_conv_param *param = data;
1928 if (write) {
1929 int val = *negp ? -*lvalp : *lvalp;
1930 if ((param->min && *param->min > val) ||
1931 (param->max && *param->max < val))
1932 return -EINVAL;
1933 *valp = val;
1934 } else {
1935 int val = *valp;
1936 if (val < 0) {
1937 *negp = -1;
1938 *lvalp = (unsigned long)-val;
1939 } else {
1940 *negp = 0;
1941 *lvalp = (unsigned long)val;
1944 return 0;
1948 * proc_dointvec_minmax - read a vector of integers with min/max values
1949 * @table: the sysctl table
1950 * @write: %TRUE if this is a write to the sysctl file
1951 * @filp: the file structure
1952 * @buffer: the user buffer
1953 * @lenp: the size of the user buffer
1954 * @ppos: file position
1956 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1957 * values from/to the user buffer, treated as an ASCII string.
1959 * This routine will ensure the values are within the range specified by
1960 * table->extra1 (min) and table->extra2 (max).
1962 * Returns 0 on success.
1964 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
1965 void __user *buffer, size_t *lenp, loff_t *ppos)
1967 struct do_proc_dointvec_minmax_conv_param param = {
1968 .min = (int *) table->extra1,
1969 .max = (int *) table->extra2,
1971 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1972 do_proc_dointvec_minmax_conv, &param);
1975 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
1976 struct file *filp,
1977 void __user *buffer,
1978 size_t *lenp, loff_t *ppos,
1979 unsigned long convmul,
1980 unsigned long convdiv)
1982 #define TMPBUFLEN 21
1983 unsigned long *i, *min, *max, val;
1984 int vleft, first=1, neg;
1985 size_t len, left;
1986 char buf[TMPBUFLEN], *p;
1987 char __user *s = buffer;
1989 if (!data || !table->maxlen || !*lenp ||
1990 (*ppos && !write)) {
1991 *lenp = 0;
1992 return 0;
1995 i = (unsigned long *) data;
1996 min = (unsigned long *) table->extra1;
1997 max = (unsigned long *) table->extra2;
1998 vleft = table->maxlen / sizeof(unsigned long);
1999 left = *lenp;
2001 for (; left && vleft--; i++, min++, max++, first=0) {
2002 if (write) {
2003 while (left) {
2004 char c;
2005 if (get_user(c, s))
2006 return -EFAULT;
2007 if (!isspace(c))
2008 break;
2009 left--;
2010 s++;
2012 if (!left)
2013 break;
2014 neg = 0;
2015 len = left;
2016 if (len > TMPBUFLEN-1)
2017 len = TMPBUFLEN-1;
2018 if (copy_from_user(buf, s, len))
2019 return -EFAULT;
2020 buf[len] = 0;
2021 p = buf;
2022 if (*p == '-' && left > 1) {
2023 neg = 1;
2024 p++;
2026 if (*p < '0' || *p > '9')
2027 break;
2028 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2029 len = p-buf;
2030 if ((len < left) && *p && !isspace(*p))
2031 break;
2032 if (neg)
2033 val = -val;
2034 s += len;
2035 left -= len;
2037 if(neg)
2038 continue;
2039 if ((min && val < *min) || (max && val > *max))
2040 continue;
2041 *i = val;
2042 } else {
2043 p = buf;
2044 if (!first)
2045 *p++ = '\t';
2046 sprintf(p, "%lu", convdiv * (*i) / convmul);
2047 len = strlen(buf);
2048 if (len > left)
2049 len = left;
2050 if(copy_to_user(s, buf, len))
2051 return -EFAULT;
2052 left -= len;
2053 s += len;
2057 if (!write && !first && left) {
2058 if(put_user('\n', s))
2059 return -EFAULT;
2060 left--, s++;
2062 if (write) {
2063 while (left) {
2064 char c;
2065 if (get_user(c, s++))
2066 return -EFAULT;
2067 if (!isspace(c))
2068 break;
2069 left--;
2072 if (write && first)
2073 return -EINVAL;
2074 *lenp -= left;
2075 *ppos += *lenp;
2076 return 0;
2077 #undef TMPBUFLEN
2080 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2081 struct file *filp,
2082 void __user *buffer,
2083 size_t *lenp, loff_t *ppos,
2084 unsigned long convmul,
2085 unsigned long convdiv)
2087 return __do_proc_doulongvec_minmax(table->data, table, write,
2088 filp, buffer, lenp, ppos, convmul, convdiv);
2092 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2093 * @table: the sysctl table
2094 * @write: %TRUE if this is a write to the sysctl file
2095 * @filp: the file structure
2096 * @buffer: the user buffer
2097 * @lenp: the size of the user buffer
2098 * @ppos: file position
2100 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2101 * values from/to the user buffer, treated as an ASCII string.
2103 * This routine will ensure the values are within the range specified by
2104 * table->extra1 (min) and table->extra2 (max).
2106 * Returns 0 on success.
2108 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2109 void __user *buffer, size_t *lenp, loff_t *ppos)
2111 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2115 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2116 * @table: the sysctl table
2117 * @write: %TRUE if this is a write to the sysctl file
2118 * @filp: the file structure
2119 * @buffer: the user buffer
2120 * @lenp: the size of the user buffer
2121 * @ppos: file position
2123 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2124 * values from/to the user buffer, treated as an ASCII string. The values
2125 * are treated as milliseconds, and converted to jiffies when they are stored.
2127 * This routine will ensure the values are within the range specified by
2128 * table->extra1 (min) and table->extra2 (max).
2130 * Returns 0 on success.
2132 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2133 struct file *filp,
2134 void __user *buffer,
2135 size_t *lenp, loff_t *ppos)
2137 return do_proc_doulongvec_minmax(table, write, filp, buffer,
2138 lenp, ppos, HZ, 1000l);
2142 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2143 int *valp,
2144 int write, void *data)
2146 if (write) {
2147 if (*lvalp > LONG_MAX / HZ)
2148 return 1;
2149 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2150 } else {
2151 int val = *valp;
2152 unsigned long lval;
2153 if (val < 0) {
2154 *negp = -1;
2155 lval = (unsigned long)-val;
2156 } else {
2157 *negp = 0;
2158 lval = (unsigned long)val;
2160 *lvalp = lval / HZ;
2162 return 0;
2165 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2166 int *valp,
2167 int write, void *data)
2169 if (write) {
2170 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2171 return 1;
2172 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2173 } else {
2174 int val = *valp;
2175 unsigned long lval;
2176 if (val < 0) {
2177 *negp = -1;
2178 lval = (unsigned long)-val;
2179 } else {
2180 *negp = 0;
2181 lval = (unsigned long)val;
2183 *lvalp = jiffies_to_clock_t(lval);
2185 return 0;
2188 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2189 int *valp,
2190 int write, void *data)
2192 if (write) {
2193 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2194 } else {
2195 int val = *valp;
2196 unsigned long lval;
2197 if (val < 0) {
2198 *negp = -1;
2199 lval = (unsigned long)-val;
2200 } else {
2201 *negp = 0;
2202 lval = (unsigned long)val;
2204 *lvalp = jiffies_to_msecs(lval);
2206 return 0;
2210 * proc_dointvec_jiffies - read a vector of integers as seconds
2211 * @table: the sysctl table
2212 * @write: %TRUE if this is a write to the sysctl file
2213 * @filp: the file structure
2214 * @buffer: the user buffer
2215 * @lenp: the size of the user buffer
2216 * @ppos: file position
2218 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2219 * values from/to the user buffer, treated as an ASCII string.
2220 * The values read are assumed to be in seconds, and are converted into
2221 * jiffies.
2223 * Returns 0 on success.
2225 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2226 void __user *buffer, size_t *lenp, loff_t *ppos)
2228 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2229 do_proc_dointvec_jiffies_conv,NULL);
2233 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2234 * @table: the sysctl table
2235 * @write: %TRUE if this is a write to the sysctl file
2236 * @filp: the file structure
2237 * @buffer: the user buffer
2238 * @lenp: the size of the user buffer
2239 * @ppos: pointer to the file position
2241 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2242 * values from/to the user buffer, treated as an ASCII string.
2243 * The values read are assumed to be in 1/USER_HZ seconds, and
2244 * are converted into jiffies.
2246 * Returns 0 on success.
2248 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2249 void __user *buffer, size_t *lenp, loff_t *ppos)
2251 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2252 do_proc_dointvec_userhz_jiffies_conv,NULL);
2256 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2257 * @table: the sysctl table
2258 * @write: %TRUE if this is a write to the sysctl file
2259 * @filp: the file structure
2260 * @buffer: the user buffer
2261 * @lenp: the size of the user buffer
2262 * @ppos: file position
2263 * @ppos: the current position in the file
2265 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2266 * values from/to the user buffer, treated as an ASCII string.
2267 * The values read are assumed to be in 1/1000 seconds, and
2268 * are converted into jiffies.
2270 * Returns 0 on success.
2272 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2273 void __user *buffer, size_t *lenp, loff_t *ppos)
2275 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2276 do_proc_dointvec_ms_jiffies_conv, NULL);
2279 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2280 void __user *buffer, size_t *lenp, loff_t *ppos)
2282 struct pid *new_pid;
2283 pid_t tmp;
2284 int r;
2286 tmp = pid_nr(cad_pid);
2288 r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2289 lenp, ppos, NULL, NULL);
2290 if (r || !write)
2291 return r;
2293 new_pid = find_get_pid(tmp);
2294 if (!new_pid)
2295 return -ESRCH;
2297 put_pid(xchg(&cad_pid, new_pid));
2298 return 0;
2301 #else /* CONFIG_PROC_FS */
2303 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2304 void __user *buffer, size_t *lenp, loff_t *ppos)
2306 return -ENOSYS;
2309 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2310 void __user *buffer, size_t *lenp, loff_t *ppos)
2312 return -ENOSYS;
2315 int proc_dointvec_bset(struct ctl_table *table, int write, struct file *filp,
2316 void __user *buffer, size_t *lenp, loff_t *ppos)
2318 return -ENOSYS;
2321 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2322 void __user *buffer, size_t *lenp, loff_t *ppos)
2324 return -ENOSYS;
2327 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2328 void __user *buffer, size_t *lenp, loff_t *ppos)
2330 return -ENOSYS;
2333 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2334 void __user *buffer, size_t *lenp, loff_t *ppos)
2336 return -ENOSYS;
2339 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2340 void __user *buffer, size_t *lenp, loff_t *ppos)
2342 return -ENOSYS;
2345 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2346 void __user *buffer, size_t *lenp, loff_t *ppos)
2348 return -ENOSYS;
2351 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2352 struct file *filp,
2353 void __user *buffer,
2354 size_t *lenp, loff_t *ppos)
2356 return -ENOSYS;
2360 #endif /* CONFIG_PROC_FS */
2363 #ifdef CONFIG_SYSCTL_SYSCALL
2365 * General sysctl support routines
2368 /* The generic sysctl data routine (used if no strategy routine supplied) */
2369 int sysctl_data(struct ctl_table *table, int __user *name, int nlen,
2370 void __user *oldval, size_t __user *oldlenp,
2371 void __user *newval, size_t newlen)
2373 size_t len;
2375 /* Get out of I don't have a variable */
2376 if (!table->data || !table->maxlen)
2377 return -ENOTDIR;
2379 if (oldval && oldlenp) {
2380 if (get_user(len, oldlenp))
2381 return -EFAULT;
2382 if (len) {
2383 if (len > table->maxlen)
2384 len = table->maxlen;
2385 if (copy_to_user(oldval, table->data, len))
2386 return -EFAULT;
2387 if (put_user(len, oldlenp))
2388 return -EFAULT;
2392 if (newval && newlen) {
2393 if (newlen > table->maxlen)
2394 newlen = table->maxlen;
2396 if (copy_from_user(table->data, newval, newlen))
2397 return -EFAULT;
2399 return 1;
2402 /* The generic string strategy routine: */
2403 int sysctl_string(struct ctl_table *table, int __user *name, int nlen,
2404 void __user *oldval, size_t __user *oldlenp,
2405 void __user *newval, size_t newlen)
2407 if (!table->data || !table->maxlen)
2408 return -ENOTDIR;
2410 if (oldval && oldlenp) {
2411 size_t bufsize;
2412 if (get_user(bufsize, oldlenp))
2413 return -EFAULT;
2414 if (bufsize) {
2415 size_t len = strlen(table->data), copied;
2417 /* This shouldn't trigger for a well-formed sysctl */
2418 if (len > table->maxlen)
2419 len = table->maxlen;
2421 /* Copy up to a max of bufsize-1 bytes of the string */
2422 copied = (len >= bufsize) ? bufsize - 1 : len;
2424 if (copy_to_user(oldval, table->data, copied) ||
2425 put_user(0, (char __user *)(oldval + copied)))
2426 return -EFAULT;
2427 if (put_user(len, oldlenp))
2428 return -EFAULT;
2431 if (newval && newlen) {
2432 size_t len = newlen;
2433 if (len > table->maxlen)
2434 len = table->maxlen;
2435 if(copy_from_user(table->data, newval, len))
2436 return -EFAULT;
2437 if (len == table->maxlen)
2438 len--;
2439 ((char *) table->data)[len] = 0;
2441 return 1;
2445 * This function makes sure that all of the integers in the vector
2446 * are between the minimum and maximum values given in the arrays
2447 * table->extra1 and table->extra2, respectively.
2449 int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen,
2450 void __user *oldval, size_t __user *oldlenp,
2451 void __user *newval, size_t newlen)
2454 if (newval && newlen) {
2455 int __user *vec = (int __user *) newval;
2456 int *min = (int *) table->extra1;
2457 int *max = (int *) table->extra2;
2458 size_t length;
2459 int i;
2461 if (newlen % sizeof(int) != 0)
2462 return -EINVAL;
2464 if (!table->extra1 && !table->extra2)
2465 return 0;
2467 if (newlen > table->maxlen)
2468 newlen = table->maxlen;
2469 length = newlen / sizeof(int);
2471 for (i = 0; i < length; i++) {
2472 int value;
2473 if (get_user(value, vec + i))
2474 return -EFAULT;
2475 if (min && value < min[i])
2476 return -EINVAL;
2477 if (max && value > max[i])
2478 return -EINVAL;
2481 return 0;
2484 /* Strategy function to convert jiffies to seconds */
2485 int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen,
2486 void __user *oldval, size_t __user *oldlenp,
2487 void __user *newval, size_t newlen)
2489 if (oldval && oldlenp) {
2490 size_t olen;
2492 if (get_user(olen, oldlenp))
2493 return -EFAULT;
2494 if (olen) {
2495 int val;
2497 if (olen < sizeof(int))
2498 return -EINVAL;
2500 val = *(int *)(table->data) / HZ;
2501 if (put_user(val, (int __user *)oldval))
2502 return -EFAULT;
2503 if (put_user(sizeof(int), oldlenp))
2504 return -EFAULT;
2507 if (newval && newlen) {
2508 int new;
2509 if (newlen != sizeof(int))
2510 return -EINVAL;
2511 if (get_user(new, (int __user *)newval))
2512 return -EFAULT;
2513 *(int *)(table->data) = new*HZ;
2515 return 1;
2518 /* Strategy function to convert jiffies to seconds */
2519 int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen,
2520 void __user *oldval, size_t __user *oldlenp,
2521 void __user *newval, size_t newlen)
2523 if (oldval && oldlenp) {
2524 size_t olen;
2526 if (get_user(olen, oldlenp))
2527 return -EFAULT;
2528 if (olen) {
2529 int val;
2531 if (olen < sizeof(int))
2532 return -EINVAL;
2534 val = jiffies_to_msecs(*(int *)(table->data));
2535 if (put_user(val, (int __user *)oldval))
2536 return -EFAULT;
2537 if (put_user(sizeof(int), oldlenp))
2538 return -EFAULT;
2541 if (newval && newlen) {
2542 int new;
2543 if (newlen != sizeof(int))
2544 return -EINVAL;
2545 if (get_user(new, (int __user *)newval))
2546 return -EFAULT;
2547 *(int *)(table->data) = msecs_to_jiffies(new);
2549 return 1;
2554 #else /* CONFIG_SYSCTL_SYSCALL */
2557 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2559 static int msg_count;
2560 struct __sysctl_args tmp;
2561 int name[CTL_MAXNAME];
2562 int i;
2564 /* Read in the sysctl name for better debug message logging */
2565 if (copy_from_user(&tmp, args, sizeof(tmp)))
2566 return -EFAULT;
2567 if (tmp.nlen <= 0 || tmp.nlen >= CTL_MAXNAME)
2568 return -ENOTDIR;
2569 for (i = 0; i < tmp.nlen; i++)
2570 if (get_user(name[i], tmp.name + i))
2571 return -EFAULT;
2573 /* Ignore accesses to kernel.version */
2574 if ((tmp.nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
2575 goto out;
2577 if (msg_count < 5) {
2578 msg_count++;
2579 printk(KERN_INFO
2580 "warning: process `%s' used the removed sysctl "
2581 "system call with ", current->comm);
2582 for (i = 0; i < tmp.nlen; i++)
2583 printk("%d.", name[i]);
2584 printk("\n");
2586 out:
2587 return -ENOSYS;
2590 int sysctl_data(struct ctl_table *table, int __user *name, int nlen,
2591 void __user *oldval, size_t __user *oldlenp,
2592 void __user *newval, size_t newlen)
2594 return -ENOSYS;
2597 int sysctl_string(struct ctl_table *table, int __user *name, int nlen,
2598 void __user *oldval, size_t __user *oldlenp,
2599 void __user *newval, size_t newlen)
2601 return -ENOSYS;
2604 int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen,
2605 void __user *oldval, size_t __user *oldlenp,
2606 void __user *newval, size_t newlen)
2608 return -ENOSYS;
2611 int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen,
2612 void __user *oldval, size_t __user *oldlenp,
2613 void __user *newval, size_t newlen)
2615 return -ENOSYS;
2618 int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen,
2619 void __user *oldval, size_t __user *oldlenp,
2620 void __user *newval, size_t newlen)
2622 return -ENOSYS;
2625 #endif /* CONFIG_SYSCTL_SYSCALL */
2628 * No sense putting this after each symbol definition, twice,
2629 * exception granted :-)
2631 EXPORT_SYMBOL(proc_dointvec);
2632 EXPORT_SYMBOL(proc_dointvec_jiffies);
2633 EXPORT_SYMBOL(proc_dointvec_minmax);
2634 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2635 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2636 EXPORT_SYMBOL(proc_dostring);
2637 EXPORT_SYMBOL(proc_doulongvec_minmax);
2638 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2639 EXPORT_SYMBOL(register_sysctl_table);
2640 EXPORT_SYMBOL(sysctl_intvec);
2641 EXPORT_SYMBOL(sysctl_jiffies);
2642 EXPORT_SYMBOL(sysctl_ms_jiffies);
2643 EXPORT_SYMBOL(sysctl_string);
2644 EXPORT_SYMBOL(sysctl_data);
2645 EXPORT_SYMBOL(unregister_sysctl_table);