i2c: Convert the pca9539 driver to a new-style i2c driver
[linux-2.6/mini2440.git] / kernel / sysctl.c
blob6b16e16428d8f57febcb2e67dde5b6c2fd211a4e
1 /*
2 * sysctl.c: General linux system control interface
4 * Begun 24 March 1995, Stephen Tweedie
5 * Added /proc support, Dec 1995
6 * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
7 * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
8 * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
9 * Dynamic registration fixes, Stephen Tweedie.
10 * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
11 * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
12 * Horn.
13 * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
14 * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
15 * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
16 * Wendling.
17 * The list_for_each() macro wasn't appropriate for the sysctl loop.
18 * Removed it and replaced it with older style, 03/23/00, Bill Wendling
21 #include <linux/module.h>
22 #include <linux/mm.h>
23 #include <linux/swap.h>
24 #include <linux/slab.h>
25 #include <linux/sysctl.h>
26 #include <linux/proc_fs.h>
27 #include <linux/security.h>
28 #include <linux/ctype.h>
29 #include <linux/utsname.h>
30 #include <linux/smp_lock.h>
31 #include <linux/fs.h>
32 #include <linux/init.h>
33 #include <linux/kernel.h>
34 #include <linux/kobject.h>
35 #include <linux/net.h>
36 #include <linux/sysrq.h>
37 #include <linux/highuid.h>
38 #include <linux/writeback.h>
39 #include <linux/hugetlb.h>
40 #include <linux/initrd.h>
41 #include <linux/key.h>
42 #include <linux/times.h>
43 #include <linux/limits.h>
44 #include <linux/dcache.h>
45 #include <linux/syscalls.h>
46 #include <linux/nfs_fs.h>
47 #include <linux/acpi.h>
48 #include <linux/reboot.h>
49 #include <linux/ftrace.h>
51 #include <asm/uaccess.h>
52 #include <asm/processor.h>
54 #ifdef CONFIG_X86
55 #include <asm/nmi.h>
56 #include <asm/stacktrace.h>
57 #include <asm/io.h>
58 #endif
60 static int deprecated_sysctl_warning(struct __sysctl_args *args);
62 #if defined(CONFIG_SYSCTL)
64 /* External variables not in a header file. */
65 extern int C_A_D;
66 extern int print_fatal_signals;
67 extern int sysctl_overcommit_memory;
68 extern int sysctl_overcommit_ratio;
69 extern int sysctl_panic_on_oom;
70 extern int sysctl_oom_kill_allocating_task;
71 extern int sysctl_oom_dump_tasks;
72 extern int max_threads;
73 extern int core_uses_pid;
74 extern int suid_dumpable;
75 extern char core_pattern[];
76 extern int pid_max;
77 extern int min_free_kbytes;
78 extern int pid_max_min, pid_max_max;
79 extern int sysctl_drop_caches;
80 extern int percpu_pagelist_fraction;
81 extern int compat_log;
82 extern int maps_protect;
83 extern int sysctl_stat_interval;
84 extern int latencytop_enabled;
85 extern int sysctl_nr_open_min, sysctl_nr_open_max;
86 #ifdef CONFIG_RCU_TORTURE_TEST
87 extern int rcutorture_runnable;
88 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
90 /* Constants used for minimum and maximum */
91 #if defined(CONFIG_DETECT_SOFTLOCKUP) || defined(CONFIG_HIGHMEM)
92 static int one = 1;
93 #endif
95 #ifdef CONFIG_DETECT_SOFTLOCKUP
96 static int sixty = 60;
97 #endif
99 #ifdef CONFIG_MMU
100 static int two = 2;
101 #endif
103 static int zero;
104 static int one_hundred = 100;
106 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
107 static int maxolduid = 65535;
108 static int minolduid;
109 static int min_percpu_pagelist_fract = 8;
111 static int ngroups_max = NGROUPS_MAX;
113 #ifdef CONFIG_KMOD
114 extern char modprobe_path[];
115 #endif
116 #ifdef CONFIG_CHR_DEV_SG
117 extern int sg_big_buff;
118 #endif
120 #ifdef __sparc__
121 extern char reboot_command [];
122 extern int stop_a_enabled;
123 extern int scons_pwroff;
124 #endif
126 #ifdef __hppa__
127 extern int pwrsw_enabled;
128 extern int unaligned_enabled;
129 #endif
131 #ifdef CONFIG_S390
132 #ifdef CONFIG_MATHEMU
133 extern int sysctl_ieee_emulation_warnings;
134 #endif
135 extern int sysctl_userprocess_debug;
136 extern int spin_retry;
137 #endif
139 #ifdef CONFIG_BSD_PROCESS_ACCT
140 extern int acct_parm[];
141 #endif
143 #ifdef CONFIG_IA64
144 extern int no_unaligned_warning;
145 #endif
147 #ifdef CONFIG_RT_MUTEXES
148 extern int max_lock_depth;
149 #endif
151 #ifdef CONFIG_PROC_SYSCTL
152 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
153 void __user *buffer, size_t *lenp, loff_t *ppos);
154 static int proc_dointvec_taint(struct ctl_table *table, int write, struct file *filp,
155 void __user *buffer, size_t *lenp, loff_t *ppos);
156 #endif
158 static struct ctl_table root_table[];
159 static struct ctl_table_root sysctl_table_root;
160 static struct ctl_table_header root_table_header = {
161 .ctl_table = root_table,
162 .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.header_list),
163 .root = &sysctl_table_root,
165 static struct ctl_table_root sysctl_table_root = {
166 .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
167 .header_list = LIST_HEAD_INIT(root_table_header.ctl_entry),
170 static struct ctl_table kern_table[];
171 static struct ctl_table vm_table[];
172 static struct ctl_table fs_table[];
173 static struct ctl_table debug_table[];
174 static struct ctl_table dev_table[];
175 extern struct ctl_table random_table[];
176 #ifdef CONFIG_INOTIFY_USER
177 extern struct ctl_table inotify_table[];
178 #endif
180 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
181 int sysctl_legacy_va_layout;
182 #endif
184 extern int prove_locking;
185 extern int lock_stat;
187 /* The default sysctl tables: */
189 static struct ctl_table root_table[] = {
191 .ctl_name = CTL_KERN,
192 .procname = "kernel",
193 .mode = 0555,
194 .child = kern_table,
197 .ctl_name = CTL_VM,
198 .procname = "vm",
199 .mode = 0555,
200 .child = vm_table,
203 .ctl_name = CTL_FS,
204 .procname = "fs",
205 .mode = 0555,
206 .child = fs_table,
209 .ctl_name = CTL_DEBUG,
210 .procname = "debug",
211 .mode = 0555,
212 .child = debug_table,
215 .ctl_name = CTL_DEV,
216 .procname = "dev",
217 .mode = 0555,
218 .child = dev_table,
221 * NOTE: do not add new entries to this table unless you have read
222 * Documentation/sysctl/ctl_unnumbered.txt
224 { .ctl_name = 0 }
227 #ifdef CONFIG_SCHED_DEBUG
228 static int min_sched_granularity_ns = 100000; /* 100 usecs */
229 static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
230 static int min_wakeup_granularity_ns; /* 0 usecs */
231 static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
232 #endif
234 static struct ctl_table kern_table[] = {
235 #ifdef CONFIG_SCHED_DEBUG
237 .ctl_name = CTL_UNNUMBERED,
238 .procname = "sched_min_granularity_ns",
239 .data = &sysctl_sched_min_granularity,
240 .maxlen = sizeof(unsigned int),
241 .mode = 0644,
242 .proc_handler = &sched_nr_latency_handler,
243 .strategy = &sysctl_intvec,
244 .extra1 = &min_sched_granularity_ns,
245 .extra2 = &max_sched_granularity_ns,
248 .ctl_name = CTL_UNNUMBERED,
249 .procname = "sched_latency_ns",
250 .data = &sysctl_sched_latency,
251 .maxlen = sizeof(unsigned int),
252 .mode = 0644,
253 .proc_handler = &sched_nr_latency_handler,
254 .strategy = &sysctl_intvec,
255 .extra1 = &min_sched_granularity_ns,
256 .extra2 = &max_sched_granularity_ns,
259 .ctl_name = CTL_UNNUMBERED,
260 .procname = "sched_wakeup_granularity_ns",
261 .data = &sysctl_sched_wakeup_granularity,
262 .maxlen = sizeof(unsigned int),
263 .mode = 0644,
264 .proc_handler = &proc_dointvec_minmax,
265 .strategy = &sysctl_intvec,
266 .extra1 = &min_wakeup_granularity_ns,
267 .extra2 = &max_wakeup_granularity_ns,
270 .ctl_name = CTL_UNNUMBERED,
271 .procname = "sched_shares_ratelimit",
272 .data = &sysctl_sched_shares_ratelimit,
273 .maxlen = sizeof(unsigned int),
274 .mode = 0644,
275 .proc_handler = &proc_dointvec,
278 .ctl_name = CTL_UNNUMBERED,
279 .procname = "sched_child_runs_first",
280 .data = &sysctl_sched_child_runs_first,
281 .maxlen = sizeof(unsigned int),
282 .mode = 0644,
283 .proc_handler = &proc_dointvec,
286 .ctl_name = CTL_UNNUMBERED,
287 .procname = "sched_features",
288 .data = &sysctl_sched_features,
289 .maxlen = sizeof(unsigned int),
290 .mode = 0644,
291 .proc_handler = &proc_dointvec,
294 .ctl_name = CTL_UNNUMBERED,
295 .procname = "sched_migration_cost",
296 .data = &sysctl_sched_migration_cost,
297 .maxlen = sizeof(unsigned int),
298 .mode = 0644,
299 .proc_handler = &proc_dointvec,
302 .ctl_name = CTL_UNNUMBERED,
303 .procname = "sched_nr_migrate",
304 .data = &sysctl_sched_nr_migrate,
305 .maxlen = sizeof(unsigned int),
306 .mode = 0644,
307 .proc_handler = &proc_dointvec,
309 #endif
311 .ctl_name = CTL_UNNUMBERED,
312 .procname = "sched_rt_period_us",
313 .data = &sysctl_sched_rt_period,
314 .maxlen = sizeof(unsigned int),
315 .mode = 0644,
316 .proc_handler = &sched_rt_handler,
319 .ctl_name = CTL_UNNUMBERED,
320 .procname = "sched_rt_runtime_us",
321 .data = &sysctl_sched_rt_runtime,
322 .maxlen = sizeof(int),
323 .mode = 0644,
324 .proc_handler = &sched_rt_handler,
327 .ctl_name = CTL_UNNUMBERED,
328 .procname = "sched_compat_yield",
329 .data = &sysctl_sched_compat_yield,
330 .maxlen = sizeof(unsigned int),
331 .mode = 0644,
332 .proc_handler = &proc_dointvec,
334 #ifdef CONFIG_PROVE_LOCKING
336 .ctl_name = CTL_UNNUMBERED,
337 .procname = "prove_locking",
338 .data = &prove_locking,
339 .maxlen = sizeof(int),
340 .mode = 0644,
341 .proc_handler = &proc_dointvec,
343 #endif
344 #ifdef CONFIG_LOCK_STAT
346 .ctl_name = CTL_UNNUMBERED,
347 .procname = "lock_stat",
348 .data = &lock_stat,
349 .maxlen = sizeof(int),
350 .mode = 0644,
351 .proc_handler = &proc_dointvec,
353 #endif
355 .ctl_name = KERN_PANIC,
356 .procname = "panic",
357 .data = &panic_timeout,
358 .maxlen = sizeof(int),
359 .mode = 0644,
360 .proc_handler = &proc_dointvec,
363 .ctl_name = KERN_CORE_USES_PID,
364 .procname = "core_uses_pid",
365 .data = &core_uses_pid,
366 .maxlen = sizeof(int),
367 .mode = 0644,
368 .proc_handler = &proc_dointvec,
371 .ctl_name = KERN_CORE_PATTERN,
372 .procname = "core_pattern",
373 .data = core_pattern,
374 .maxlen = CORENAME_MAX_SIZE,
375 .mode = 0644,
376 .proc_handler = &proc_dostring,
377 .strategy = &sysctl_string,
379 #ifdef CONFIG_PROC_SYSCTL
381 .procname = "tainted",
382 .data = &tainted,
383 .maxlen = sizeof(int),
384 .mode = 0644,
385 .proc_handler = &proc_dointvec_taint,
387 #endif
388 #ifdef CONFIG_LATENCYTOP
390 .procname = "latencytop",
391 .data = &latencytop_enabled,
392 .maxlen = sizeof(int),
393 .mode = 0644,
394 .proc_handler = &proc_dointvec,
396 #endif
397 #ifdef CONFIG_BLK_DEV_INITRD
399 .ctl_name = KERN_REALROOTDEV,
400 .procname = "real-root-dev",
401 .data = &real_root_dev,
402 .maxlen = sizeof(int),
403 .mode = 0644,
404 .proc_handler = &proc_dointvec,
406 #endif
408 .ctl_name = CTL_UNNUMBERED,
409 .procname = "print-fatal-signals",
410 .data = &print_fatal_signals,
411 .maxlen = sizeof(int),
412 .mode = 0644,
413 .proc_handler = &proc_dointvec,
415 #ifdef __sparc__
417 .ctl_name = KERN_SPARC_REBOOT,
418 .procname = "reboot-cmd",
419 .data = reboot_command,
420 .maxlen = 256,
421 .mode = 0644,
422 .proc_handler = &proc_dostring,
423 .strategy = &sysctl_string,
426 .ctl_name = KERN_SPARC_STOP_A,
427 .procname = "stop-a",
428 .data = &stop_a_enabled,
429 .maxlen = sizeof (int),
430 .mode = 0644,
431 .proc_handler = &proc_dointvec,
434 .ctl_name = KERN_SPARC_SCONS_PWROFF,
435 .procname = "scons-poweroff",
436 .data = &scons_pwroff,
437 .maxlen = sizeof (int),
438 .mode = 0644,
439 .proc_handler = &proc_dointvec,
441 #endif
442 #ifdef __hppa__
444 .ctl_name = KERN_HPPA_PWRSW,
445 .procname = "soft-power",
446 .data = &pwrsw_enabled,
447 .maxlen = sizeof (int),
448 .mode = 0644,
449 .proc_handler = &proc_dointvec,
452 .ctl_name = KERN_HPPA_UNALIGNED,
453 .procname = "unaligned-trap",
454 .data = &unaligned_enabled,
455 .maxlen = sizeof (int),
456 .mode = 0644,
457 .proc_handler = &proc_dointvec,
459 #endif
461 .ctl_name = KERN_CTLALTDEL,
462 .procname = "ctrl-alt-del",
463 .data = &C_A_D,
464 .maxlen = sizeof(int),
465 .mode = 0644,
466 .proc_handler = &proc_dointvec,
468 #ifdef CONFIG_FTRACE
470 .ctl_name = CTL_UNNUMBERED,
471 .procname = "ftrace_enabled",
472 .data = &ftrace_enabled,
473 .maxlen = sizeof(int),
474 .mode = 0644,
475 .proc_handler = &ftrace_enable_sysctl,
477 #endif
478 #ifdef CONFIG_KMOD
480 .ctl_name = KERN_MODPROBE,
481 .procname = "modprobe",
482 .data = &modprobe_path,
483 .maxlen = KMOD_PATH_LEN,
484 .mode = 0644,
485 .proc_handler = &proc_dostring,
486 .strategy = &sysctl_string,
488 #endif
489 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
491 .ctl_name = KERN_HOTPLUG,
492 .procname = "hotplug",
493 .data = &uevent_helper,
494 .maxlen = UEVENT_HELPER_PATH_LEN,
495 .mode = 0644,
496 .proc_handler = &proc_dostring,
497 .strategy = &sysctl_string,
499 #endif
500 #ifdef CONFIG_CHR_DEV_SG
502 .ctl_name = KERN_SG_BIG_BUFF,
503 .procname = "sg-big-buff",
504 .data = &sg_big_buff,
505 .maxlen = sizeof (int),
506 .mode = 0444,
507 .proc_handler = &proc_dointvec,
509 #endif
510 #ifdef CONFIG_BSD_PROCESS_ACCT
512 .ctl_name = KERN_ACCT,
513 .procname = "acct",
514 .data = &acct_parm,
515 .maxlen = 3*sizeof(int),
516 .mode = 0644,
517 .proc_handler = &proc_dointvec,
519 #endif
520 #ifdef CONFIG_MAGIC_SYSRQ
522 .ctl_name = KERN_SYSRQ,
523 .procname = "sysrq",
524 .data = &__sysrq_enabled,
525 .maxlen = sizeof (int),
526 .mode = 0644,
527 .proc_handler = &proc_dointvec,
529 #endif
530 #ifdef CONFIG_PROC_SYSCTL
532 .procname = "cad_pid",
533 .data = NULL,
534 .maxlen = sizeof (int),
535 .mode = 0600,
536 .proc_handler = &proc_do_cad_pid,
538 #endif
540 .ctl_name = KERN_MAX_THREADS,
541 .procname = "threads-max",
542 .data = &max_threads,
543 .maxlen = sizeof(int),
544 .mode = 0644,
545 .proc_handler = &proc_dointvec,
548 .ctl_name = KERN_RANDOM,
549 .procname = "random",
550 .mode = 0555,
551 .child = random_table,
554 .ctl_name = KERN_OVERFLOWUID,
555 .procname = "overflowuid",
556 .data = &overflowuid,
557 .maxlen = sizeof(int),
558 .mode = 0644,
559 .proc_handler = &proc_dointvec_minmax,
560 .strategy = &sysctl_intvec,
561 .extra1 = &minolduid,
562 .extra2 = &maxolduid,
565 .ctl_name = KERN_OVERFLOWGID,
566 .procname = "overflowgid",
567 .data = &overflowgid,
568 .maxlen = sizeof(int),
569 .mode = 0644,
570 .proc_handler = &proc_dointvec_minmax,
571 .strategy = &sysctl_intvec,
572 .extra1 = &minolduid,
573 .extra2 = &maxolduid,
575 #ifdef CONFIG_S390
576 #ifdef CONFIG_MATHEMU
578 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
579 .procname = "ieee_emulation_warnings",
580 .data = &sysctl_ieee_emulation_warnings,
581 .maxlen = sizeof(int),
582 .mode = 0644,
583 .proc_handler = &proc_dointvec,
585 #endif
587 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
588 .procname = "userprocess_debug",
589 .data = &sysctl_userprocess_debug,
590 .maxlen = sizeof(int),
591 .mode = 0644,
592 .proc_handler = &proc_dointvec,
594 #endif
596 .ctl_name = KERN_PIDMAX,
597 .procname = "pid_max",
598 .data = &pid_max,
599 .maxlen = sizeof (int),
600 .mode = 0644,
601 .proc_handler = &proc_dointvec_minmax,
602 .strategy = sysctl_intvec,
603 .extra1 = &pid_max_min,
604 .extra2 = &pid_max_max,
607 .ctl_name = KERN_PANIC_ON_OOPS,
608 .procname = "panic_on_oops",
609 .data = &panic_on_oops,
610 .maxlen = sizeof(int),
611 .mode = 0644,
612 .proc_handler = &proc_dointvec,
614 #if defined CONFIG_PRINTK
616 .ctl_name = KERN_PRINTK,
617 .procname = "printk",
618 .data = &console_loglevel,
619 .maxlen = 4*sizeof(int),
620 .mode = 0644,
621 .proc_handler = &proc_dointvec,
624 .ctl_name = KERN_PRINTK_RATELIMIT,
625 .procname = "printk_ratelimit",
626 .data = &printk_ratelimit_jiffies,
627 .maxlen = sizeof(int),
628 .mode = 0644,
629 .proc_handler = &proc_dointvec_jiffies,
630 .strategy = &sysctl_jiffies,
633 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
634 .procname = "printk_ratelimit_burst",
635 .data = &printk_ratelimit_burst,
636 .maxlen = sizeof(int),
637 .mode = 0644,
638 .proc_handler = &proc_dointvec,
640 #endif
642 .ctl_name = KERN_NGROUPS_MAX,
643 .procname = "ngroups_max",
644 .data = &ngroups_max,
645 .maxlen = sizeof (int),
646 .mode = 0444,
647 .proc_handler = &proc_dointvec,
649 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
651 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
652 .procname = "unknown_nmi_panic",
653 .data = &unknown_nmi_panic,
654 .maxlen = sizeof (int),
655 .mode = 0644,
656 .proc_handler = &proc_dointvec,
659 .procname = "nmi_watchdog",
660 .data = &nmi_watchdog_enabled,
661 .maxlen = sizeof (int),
662 .mode = 0644,
663 .proc_handler = &proc_nmi_enabled,
665 #endif
666 #if defined(CONFIG_X86)
668 .ctl_name = KERN_PANIC_ON_NMI,
669 .procname = "panic_on_unrecovered_nmi",
670 .data = &panic_on_unrecovered_nmi,
671 .maxlen = sizeof(int),
672 .mode = 0644,
673 .proc_handler = &proc_dointvec,
676 .ctl_name = KERN_BOOTLOADER_TYPE,
677 .procname = "bootloader_type",
678 .data = &bootloader_type,
679 .maxlen = sizeof (int),
680 .mode = 0444,
681 .proc_handler = &proc_dointvec,
684 .ctl_name = CTL_UNNUMBERED,
685 .procname = "kstack_depth_to_print",
686 .data = &kstack_depth_to_print,
687 .maxlen = sizeof(int),
688 .mode = 0644,
689 .proc_handler = &proc_dointvec,
692 .ctl_name = CTL_UNNUMBERED,
693 .procname = "io_delay_type",
694 .data = &io_delay_type,
695 .maxlen = sizeof(int),
696 .mode = 0644,
697 .proc_handler = &proc_dointvec,
699 #endif
700 #if defined(CONFIG_MMU)
702 .ctl_name = KERN_RANDOMIZE,
703 .procname = "randomize_va_space",
704 .data = &randomize_va_space,
705 .maxlen = sizeof(int),
706 .mode = 0644,
707 .proc_handler = &proc_dointvec,
709 #endif
710 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
712 .ctl_name = KERN_SPIN_RETRY,
713 .procname = "spin_retry",
714 .data = &spin_retry,
715 .maxlen = sizeof (int),
716 .mode = 0644,
717 .proc_handler = &proc_dointvec,
719 #endif
720 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
722 .procname = "acpi_video_flags",
723 .data = &acpi_realmode_flags,
724 .maxlen = sizeof (unsigned long),
725 .mode = 0644,
726 .proc_handler = &proc_doulongvec_minmax,
728 #endif
729 #ifdef CONFIG_IA64
731 .ctl_name = KERN_IA64_UNALIGNED,
732 .procname = "ignore-unaligned-usertrap",
733 .data = &no_unaligned_warning,
734 .maxlen = sizeof (int),
735 .mode = 0644,
736 .proc_handler = &proc_dointvec,
738 #endif
739 #ifdef CONFIG_DETECT_SOFTLOCKUP
741 .ctl_name = CTL_UNNUMBERED,
742 .procname = "softlockup_thresh",
743 .data = &softlockup_thresh,
744 .maxlen = sizeof(unsigned long),
745 .mode = 0644,
746 .proc_handler = &proc_doulongvec_minmax,
747 .strategy = &sysctl_intvec,
748 .extra1 = &one,
749 .extra2 = &sixty,
752 .ctl_name = CTL_UNNUMBERED,
753 .procname = "hung_task_check_count",
754 .data = &sysctl_hung_task_check_count,
755 .maxlen = sizeof(unsigned long),
756 .mode = 0644,
757 .proc_handler = &proc_doulongvec_minmax,
758 .strategy = &sysctl_intvec,
761 .ctl_name = CTL_UNNUMBERED,
762 .procname = "hung_task_timeout_secs",
763 .data = &sysctl_hung_task_timeout_secs,
764 .maxlen = sizeof(unsigned long),
765 .mode = 0644,
766 .proc_handler = &proc_doulongvec_minmax,
767 .strategy = &sysctl_intvec,
770 .ctl_name = CTL_UNNUMBERED,
771 .procname = "hung_task_warnings",
772 .data = &sysctl_hung_task_warnings,
773 .maxlen = sizeof(unsigned long),
774 .mode = 0644,
775 .proc_handler = &proc_doulongvec_minmax,
776 .strategy = &sysctl_intvec,
778 #endif
779 #ifdef CONFIG_COMPAT
781 .ctl_name = KERN_COMPAT_LOG,
782 .procname = "compat-log",
783 .data = &compat_log,
784 .maxlen = sizeof (int),
785 .mode = 0644,
786 .proc_handler = &proc_dointvec,
788 #endif
789 #ifdef CONFIG_RT_MUTEXES
791 .ctl_name = KERN_MAX_LOCK_DEPTH,
792 .procname = "max_lock_depth",
793 .data = &max_lock_depth,
794 .maxlen = sizeof(int),
795 .mode = 0644,
796 .proc_handler = &proc_dointvec,
798 #endif
799 #ifdef CONFIG_PROC_FS
801 .ctl_name = CTL_UNNUMBERED,
802 .procname = "maps_protect",
803 .data = &maps_protect,
804 .maxlen = sizeof(int),
805 .mode = 0644,
806 .proc_handler = &proc_dointvec,
808 #endif
810 .ctl_name = CTL_UNNUMBERED,
811 .procname = "poweroff_cmd",
812 .data = &poweroff_cmd,
813 .maxlen = POWEROFF_CMD_PATH_LEN,
814 .mode = 0644,
815 .proc_handler = &proc_dostring,
816 .strategy = &sysctl_string,
818 #ifdef CONFIG_KEYS
820 .ctl_name = CTL_UNNUMBERED,
821 .procname = "keys",
822 .mode = 0555,
823 .child = key_sysctls,
825 #endif
826 #ifdef CONFIG_RCU_TORTURE_TEST
828 .ctl_name = CTL_UNNUMBERED,
829 .procname = "rcutorture_runnable",
830 .data = &rcutorture_runnable,
831 .maxlen = sizeof(int),
832 .mode = 0644,
833 .proc_handler = &proc_dointvec,
835 #endif
837 * NOTE: do not add new entries to this table unless you have read
838 * Documentation/sysctl/ctl_unnumbered.txt
840 { .ctl_name = 0 }
843 static struct ctl_table vm_table[] = {
845 .ctl_name = VM_OVERCOMMIT_MEMORY,
846 .procname = "overcommit_memory",
847 .data = &sysctl_overcommit_memory,
848 .maxlen = sizeof(sysctl_overcommit_memory),
849 .mode = 0644,
850 .proc_handler = &proc_dointvec,
853 .ctl_name = VM_PANIC_ON_OOM,
854 .procname = "panic_on_oom",
855 .data = &sysctl_panic_on_oom,
856 .maxlen = sizeof(sysctl_panic_on_oom),
857 .mode = 0644,
858 .proc_handler = &proc_dointvec,
861 .ctl_name = CTL_UNNUMBERED,
862 .procname = "oom_kill_allocating_task",
863 .data = &sysctl_oom_kill_allocating_task,
864 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
865 .mode = 0644,
866 .proc_handler = &proc_dointvec,
869 .ctl_name = CTL_UNNUMBERED,
870 .procname = "oom_dump_tasks",
871 .data = &sysctl_oom_dump_tasks,
872 .maxlen = sizeof(sysctl_oom_dump_tasks),
873 .mode = 0644,
874 .proc_handler = &proc_dointvec,
877 .ctl_name = VM_OVERCOMMIT_RATIO,
878 .procname = "overcommit_ratio",
879 .data = &sysctl_overcommit_ratio,
880 .maxlen = sizeof(sysctl_overcommit_ratio),
881 .mode = 0644,
882 .proc_handler = &proc_dointvec,
885 .ctl_name = VM_PAGE_CLUSTER,
886 .procname = "page-cluster",
887 .data = &page_cluster,
888 .maxlen = sizeof(int),
889 .mode = 0644,
890 .proc_handler = &proc_dointvec,
893 .ctl_name = VM_DIRTY_BACKGROUND,
894 .procname = "dirty_background_ratio",
895 .data = &dirty_background_ratio,
896 .maxlen = sizeof(dirty_background_ratio),
897 .mode = 0644,
898 .proc_handler = &proc_dointvec_minmax,
899 .strategy = &sysctl_intvec,
900 .extra1 = &zero,
901 .extra2 = &one_hundred,
904 .ctl_name = VM_DIRTY_RATIO,
905 .procname = "dirty_ratio",
906 .data = &vm_dirty_ratio,
907 .maxlen = sizeof(vm_dirty_ratio),
908 .mode = 0644,
909 .proc_handler = &dirty_ratio_handler,
910 .strategy = &sysctl_intvec,
911 .extra1 = &zero,
912 .extra2 = &one_hundred,
915 .procname = "dirty_writeback_centisecs",
916 .data = &dirty_writeback_interval,
917 .maxlen = sizeof(dirty_writeback_interval),
918 .mode = 0644,
919 .proc_handler = &dirty_writeback_centisecs_handler,
922 .procname = "dirty_expire_centisecs",
923 .data = &dirty_expire_interval,
924 .maxlen = sizeof(dirty_expire_interval),
925 .mode = 0644,
926 .proc_handler = &proc_dointvec_userhz_jiffies,
929 .ctl_name = VM_NR_PDFLUSH_THREADS,
930 .procname = "nr_pdflush_threads",
931 .data = &nr_pdflush_threads,
932 .maxlen = sizeof nr_pdflush_threads,
933 .mode = 0444 /* read-only*/,
934 .proc_handler = &proc_dointvec,
937 .ctl_name = VM_SWAPPINESS,
938 .procname = "swappiness",
939 .data = &vm_swappiness,
940 .maxlen = sizeof(vm_swappiness),
941 .mode = 0644,
942 .proc_handler = &proc_dointvec_minmax,
943 .strategy = &sysctl_intvec,
944 .extra1 = &zero,
945 .extra2 = &one_hundred,
947 #ifdef CONFIG_HUGETLB_PAGE
949 .procname = "nr_hugepages",
950 .data = &max_huge_pages,
951 .maxlen = sizeof(unsigned long),
952 .mode = 0644,
953 .proc_handler = &hugetlb_sysctl_handler,
954 .extra1 = (void *)&hugetlb_zero,
955 .extra2 = (void *)&hugetlb_infinity,
958 .ctl_name = VM_HUGETLB_GROUP,
959 .procname = "hugetlb_shm_group",
960 .data = &sysctl_hugetlb_shm_group,
961 .maxlen = sizeof(gid_t),
962 .mode = 0644,
963 .proc_handler = &proc_dointvec,
966 .ctl_name = CTL_UNNUMBERED,
967 .procname = "hugepages_treat_as_movable",
968 .data = &hugepages_treat_as_movable,
969 .maxlen = sizeof(int),
970 .mode = 0644,
971 .proc_handler = &hugetlb_treat_movable_handler,
974 .ctl_name = CTL_UNNUMBERED,
975 .procname = "nr_overcommit_hugepages",
976 .data = &sysctl_overcommit_huge_pages,
977 .maxlen = sizeof(sysctl_overcommit_huge_pages),
978 .mode = 0644,
979 .proc_handler = &hugetlb_overcommit_handler,
981 #endif
983 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
984 .procname = "lowmem_reserve_ratio",
985 .data = &sysctl_lowmem_reserve_ratio,
986 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
987 .mode = 0644,
988 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
989 .strategy = &sysctl_intvec,
992 .ctl_name = VM_DROP_PAGECACHE,
993 .procname = "drop_caches",
994 .data = &sysctl_drop_caches,
995 .maxlen = sizeof(int),
996 .mode = 0644,
997 .proc_handler = drop_caches_sysctl_handler,
998 .strategy = &sysctl_intvec,
1001 .ctl_name = VM_MIN_FREE_KBYTES,
1002 .procname = "min_free_kbytes",
1003 .data = &min_free_kbytes,
1004 .maxlen = sizeof(min_free_kbytes),
1005 .mode = 0644,
1006 .proc_handler = &min_free_kbytes_sysctl_handler,
1007 .strategy = &sysctl_intvec,
1008 .extra1 = &zero,
1011 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
1012 .procname = "percpu_pagelist_fraction",
1013 .data = &percpu_pagelist_fraction,
1014 .maxlen = sizeof(percpu_pagelist_fraction),
1015 .mode = 0644,
1016 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
1017 .strategy = &sysctl_intvec,
1018 .extra1 = &min_percpu_pagelist_fract,
1020 #ifdef CONFIG_MMU
1022 .ctl_name = VM_MAX_MAP_COUNT,
1023 .procname = "max_map_count",
1024 .data = &sysctl_max_map_count,
1025 .maxlen = sizeof(sysctl_max_map_count),
1026 .mode = 0644,
1027 .proc_handler = &proc_dointvec
1029 #endif
1031 .ctl_name = VM_LAPTOP_MODE,
1032 .procname = "laptop_mode",
1033 .data = &laptop_mode,
1034 .maxlen = sizeof(laptop_mode),
1035 .mode = 0644,
1036 .proc_handler = &proc_dointvec_jiffies,
1037 .strategy = &sysctl_jiffies,
1040 .ctl_name = VM_BLOCK_DUMP,
1041 .procname = "block_dump",
1042 .data = &block_dump,
1043 .maxlen = sizeof(block_dump),
1044 .mode = 0644,
1045 .proc_handler = &proc_dointvec,
1046 .strategy = &sysctl_intvec,
1047 .extra1 = &zero,
1050 .ctl_name = VM_VFS_CACHE_PRESSURE,
1051 .procname = "vfs_cache_pressure",
1052 .data = &sysctl_vfs_cache_pressure,
1053 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1054 .mode = 0644,
1055 .proc_handler = &proc_dointvec,
1056 .strategy = &sysctl_intvec,
1057 .extra1 = &zero,
1059 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1061 .ctl_name = VM_LEGACY_VA_LAYOUT,
1062 .procname = "legacy_va_layout",
1063 .data = &sysctl_legacy_va_layout,
1064 .maxlen = sizeof(sysctl_legacy_va_layout),
1065 .mode = 0644,
1066 .proc_handler = &proc_dointvec,
1067 .strategy = &sysctl_intvec,
1068 .extra1 = &zero,
1070 #endif
1071 #ifdef CONFIG_NUMA
1073 .ctl_name = VM_ZONE_RECLAIM_MODE,
1074 .procname = "zone_reclaim_mode",
1075 .data = &zone_reclaim_mode,
1076 .maxlen = sizeof(zone_reclaim_mode),
1077 .mode = 0644,
1078 .proc_handler = &proc_dointvec,
1079 .strategy = &sysctl_intvec,
1080 .extra1 = &zero,
1083 .ctl_name = VM_MIN_UNMAPPED,
1084 .procname = "min_unmapped_ratio",
1085 .data = &sysctl_min_unmapped_ratio,
1086 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1087 .mode = 0644,
1088 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
1089 .strategy = &sysctl_intvec,
1090 .extra1 = &zero,
1091 .extra2 = &one_hundred,
1094 .ctl_name = VM_MIN_SLAB,
1095 .procname = "min_slab_ratio",
1096 .data = &sysctl_min_slab_ratio,
1097 .maxlen = sizeof(sysctl_min_slab_ratio),
1098 .mode = 0644,
1099 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler,
1100 .strategy = &sysctl_intvec,
1101 .extra1 = &zero,
1102 .extra2 = &one_hundred,
1104 #endif
1105 #ifdef CONFIG_SMP
1107 .ctl_name = CTL_UNNUMBERED,
1108 .procname = "stat_interval",
1109 .data = &sysctl_stat_interval,
1110 .maxlen = sizeof(sysctl_stat_interval),
1111 .mode = 0644,
1112 .proc_handler = &proc_dointvec_jiffies,
1113 .strategy = &sysctl_jiffies,
1115 #endif
1116 #ifdef CONFIG_SECURITY
1118 .ctl_name = CTL_UNNUMBERED,
1119 .procname = "mmap_min_addr",
1120 .data = &mmap_min_addr,
1121 .maxlen = sizeof(unsigned long),
1122 .mode = 0644,
1123 .proc_handler = &proc_doulongvec_minmax,
1125 #endif
1126 #ifdef CONFIG_NUMA
1128 .ctl_name = CTL_UNNUMBERED,
1129 .procname = "numa_zonelist_order",
1130 .data = &numa_zonelist_order,
1131 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1132 .mode = 0644,
1133 .proc_handler = &numa_zonelist_order_handler,
1134 .strategy = &sysctl_string,
1136 #endif
1137 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1138 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1140 .ctl_name = VM_VDSO_ENABLED,
1141 .procname = "vdso_enabled",
1142 .data = &vdso_enabled,
1143 .maxlen = sizeof(vdso_enabled),
1144 .mode = 0644,
1145 .proc_handler = &proc_dointvec,
1146 .strategy = &sysctl_intvec,
1147 .extra1 = &zero,
1149 #endif
1150 #ifdef CONFIG_HIGHMEM
1152 .ctl_name = CTL_UNNUMBERED,
1153 .procname = "highmem_is_dirtyable",
1154 .data = &vm_highmem_is_dirtyable,
1155 .maxlen = sizeof(vm_highmem_is_dirtyable),
1156 .mode = 0644,
1157 .proc_handler = &proc_dointvec_minmax,
1158 .strategy = &sysctl_intvec,
1159 .extra1 = &zero,
1160 .extra2 = &one,
1162 #endif
1164 * NOTE: do not add new entries to this table unless you have read
1165 * Documentation/sysctl/ctl_unnumbered.txt
1167 { .ctl_name = 0 }
1170 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1171 static struct ctl_table binfmt_misc_table[] = {
1172 { .ctl_name = 0 }
1174 #endif
1176 static struct ctl_table fs_table[] = {
1178 .ctl_name = FS_NRINODE,
1179 .procname = "inode-nr",
1180 .data = &inodes_stat,
1181 .maxlen = 2*sizeof(int),
1182 .mode = 0444,
1183 .proc_handler = &proc_dointvec,
1186 .ctl_name = FS_STATINODE,
1187 .procname = "inode-state",
1188 .data = &inodes_stat,
1189 .maxlen = 7*sizeof(int),
1190 .mode = 0444,
1191 .proc_handler = &proc_dointvec,
1194 .procname = "file-nr",
1195 .data = &files_stat,
1196 .maxlen = 3*sizeof(int),
1197 .mode = 0444,
1198 .proc_handler = &proc_nr_files,
1201 .ctl_name = FS_MAXFILE,
1202 .procname = "file-max",
1203 .data = &files_stat.max_files,
1204 .maxlen = sizeof(int),
1205 .mode = 0644,
1206 .proc_handler = &proc_dointvec,
1209 .ctl_name = CTL_UNNUMBERED,
1210 .procname = "nr_open",
1211 .data = &sysctl_nr_open,
1212 .maxlen = sizeof(int),
1213 .mode = 0644,
1214 .proc_handler = &proc_dointvec_minmax,
1215 .extra1 = &sysctl_nr_open_min,
1216 .extra2 = &sysctl_nr_open_max,
1219 .ctl_name = FS_DENTRY,
1220 .procname = "dentry-state",
1221 .data = &dentry_stat,
1222 .maxlen = 6*sizeof(int),
1223 .mode = 0444,
1224 .proc_handler = &proc_dointvec,
1227 .ctl_name = FS_OVERFLOWUID,
1228 .procname = "overflowuid",
1229 .data = &fs_overflowuid,
1230 .maxlen = sizeof(int),
1231 .mode = 0644,
1232 .proc_handler = &proc_dointvec_minmax,
1233 .strategy = &sysctl_intvec,
1234 .extra1 = &minolduid,
1235 .extra2 = &maxolduid,
1238 .ctl_name = FS_OVERFLOWGID,
1239 .procname = "overflowgid",
1240 .data = &fs_overflowgid,
1241 .maxlen = sizeof(int),
1242 .mode = 0644,
1243 .proc_handler = &proc_dointvec_minmax,
1244 .strategy = &sysctl_intvec,
1245 .extra1 = &minolduid,
1246 .extra2 = &maxolduid,
1249 .ctl_name = FS_LEASES,
1250 .procname = "leases-enable",
1251 .data = &leases_enable,
1252 .maxlen = sizeof(int),
1253 .mode = 0644,
1254 .proc_handler = &proc_dointvec,
1256 #ifdef CONFIG_DNOTIFY
1258 .ctl_name = FS_DIR_NOTIFY,
1259 .procname = "dir-notify-enable",
1260 .data = &dir_notify_enable,
1261 .maxlen = sizeof(int),
1262 .mode = 0644,
1263 .proc_handler = &proc_dointvec,
1265 #endif
1266 #ifdef CONFIG_MMU
1268 .ctl_name = FS_LEASE_TIME,
1269 .procname = "lease-break-time",
1270 .data = &lease_break_time,
1271 .maxlen = sizeof(int),
1272 .mode = 0644,
1273 .proc_handler = &proc_dointvec_minmax,
1274 .strategy = &sysctl_intvec,
1275 .extra1 = &zero,
1276 .extra2 = &two,
1279 .procname = "aio-nr",
1280 .data = &aio_nr,
1281 .maxlen = sizeof(aio_nr),
1282 .mode = 0444,
1283 .proc_handler = &proc_doulongvec_minmax,
1286 .procname = "aio-max-nr",
1287 .data = &aio_max_nr,
1288 .maxlen = sizeof(aio_max_nr),
1289 .mode = 0644,
1290 .proc_handler = &proc_doulongvec_minmax,
1292 #ifdef CONFIG_INOTIFY_USER
1294 .ctl_name = FS_INOTIFY,
1295 .procname = "inotify",
1296 .mode = 0555,
1297 .child = inotify_table,
1299 #endif
1300 #endif
1302 .ctl_name = KERN_SETUID_DUMPABLE,
1303 .procname = "suid_dumpable",
1304 .data = &suid_dumpable,
1305 .maxlen = sizeof(int),
1306 .mode = 0644,
1307 .proc_handler = &proc_dointvec,
1309 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1311 .ctl_name = CTL_UNNUMBERED,
1312 .procname = "binfmt_misc",
1313 .mode = 0555,
1314 .child = binfmt_misc_table,
1316 #endif
1318 * NOTE: do not add new entries to this table unless you have read
1319 * Documentation/sysctl/ctl_unnumbered.txt
1321 { .ctl_name = 0 }
1324 static struct ctl_table debug_table[] = {
1325 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1327 .ctl_name = CTL_UNNUMBERED,
1328 .procname = "exception-trace",
1329 .data = &show_unhandled_signals,
1330 .maxlen = sizeof(int),
1331 .mode = 0644,
1332 .proc_handler = proc_dointvec
1334 #endif
1335 { .ctl_name = 0 }
1338 static struct ctl_table dev_table[] = {
1339 { .ctl_name = 0 }
1342 static DEFINE_SPINLOCK(sysctl_lock);
1344 /* called under sysctl_lock */
1345 static int use_table(struct ctl_table_header *p)
1347 if (unlikely(p->unregistering))
1348 return 0;
1349 p->used++;
1350 return 1;
1353 /* called under sysctl_lock */
1354 static void unuse_table(struct ctl_table_header *p)
1356 if (!--p->used)
1357 if (unlikely(p->unregistering))
1358 complete(p->unregistering);
1361 /* called under sysctl_lock, will reacquire if has to wait */
1362 static void start_unregistering(struct ctl_table_header *p)
1365 * if p->used is 0, nobody will ever touch that entry again;
1366 * we'll eliminate all paths to it before dropping sysctl_lock
1368 if (unlikely(p->used)) {
1369 struct completion wait;
1370 init_completion(&wait);
1371 p->unregistering = &wait;
1372 spin_unlock(&sysctl_lock);
1373 wait_for_completion(&wait);
1374 spin_lock(&sysctl_lock);
1377 * do not remove from the list until nobody holds it; walking the
1378 * list in do_sysctl() relies on that.
1380 list_del_init(&p->ctl_entry);
1383 void sysctl_head_finish(struct ctl_table_header *head)
1385 if (!head)
1386 return;
1387 spin_lock(&sysctl_lock);
1388 unuse_table(head);
1389 spin_unlock(&sysctl_lock);
1392 static struct list_head *
1393 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1395 struct list_head *header_list;
1396 header_list = &root->header_list;
1397 if (root->lookup)
1398 header_list = root->lookup(root, namespaces);
1399 return header_list;
1402 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1403 struct ctl_table_header *prev)
1405 struct ctl_table_root *root;
1406 struct list_head *header_list;
1407 struct ctl_table_header *head;
1408 struct list_head *tmp;
1410 spin_lock(&sysctl_lock);
1411 if (prev) {
1412 head = prev;
1413 tmp = &prev->ctl_entry;
1414 unuse_table(prev);
1415 goto next;
1417 tmp = &root_table_header.ctl_entry;
1418 for (;;) {
1419 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1421 if (!use_table(head))
1422 goto next;
1423 spin_unlock(&sysctl_lock);
1424 return head;
1425 next:
1426 root = head->root;
1427 tmp = tmp->next;
1428 header_list = lookup_header_list(root, namespaces);
1429 if (tmp != header_list)
1430 continue;
1432 do {
1433 root = list_entry(root->root_list.next,
1434 struct ctl_table_root, root_list);
1435 if (root == &sysctl_table_root)
1436 goto out;
1437 header_list = lookup_header_list(root, namespaces);
1438 } while (list_empty(header_list));
1439 tmp = header_list->next;
1441 out:
1442 spin_unlock(&sysctl_lock);
1443 return NULL;
1446 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1448 return __sysctl_head_next(current->nsproxy, prev);
1451 void register_sysctl_root(struct ctl_table_root *root)
1453 spin_lock(&sysctl_lock);
1454 list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1455 spin_unlock(&sysctl_lock);
1458 #ifdef CONFIG_SYSCTL_SYSCALL
1459 /* Perform the actual read/write of a sysctl table entry. */
1460 static int do_sysctl_strategy(struct ctl_table_root *root,
1461 struct ctl_table *table,
1462 int __user *name, int nlen,
1463 void __user *oldval, size_t __user *oldlenp,
1464 void __user *newval, size_t newlen)
1466 int op = 0, rc;
1468 if (oldval)
1469 op |= 004;
1470 if (newval)
1471 op |= 002;
1472 if (sysctl_perm(root, table, op))
1473 return -EPERM;
1475 if (table->strategy) {
1476 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1477 newval, newlen);
1478 if (rc < 0)
1479 return rc;
1480 if (rc > 0)
1481 return 0;
1484 /* If there is no strategy routine, or if the strategy returns
1485 * zero, proceed with automatic r/w */
1486 if (table->data && table->maxlen) {
1487 rc = sysctl_data(table, name, nlen, oldval, oldlenp,
1488 newval, newlen);
1489 if (rc < 0)
1490 return rc;
1492 return 0;
1495 static int parse_table(int __user *name, int nlen,
1496 void __user *oldval, size_t __user *oldlenp,
1497 void __user *newval, size_t newlen,
1498 struct ctl_table_root *root,
1499 struct ctl_table *table)
1501 int n;
1502 repeat:
1503 if (!nlen)
1504 return -ENOTDIR;
1505 if (get_user(n, name))
1506 return -EFAULT;
1507 for ( ; table->ctl_name || table->procname; table++) {
1508 if (!table->ctl_name)
1509 continue;
1510 if (n == table->ctl_name) {
1511 int error;
1512 if (table->child) {
1513 if (sysctl_perm(root, table, 001))
1514 return -EPERM;
1515 name++;
1516 nlen--;
1517 table = table->child;
1518 goto repeat;
1520 error = do_sysctl_strategy(root, table, name, nlen,
1521 oldval, oldlenp,
1522 newval, newlen);
1523 return error;
1526 return -ENOTDIR;
1529 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1530 void __user *newval, size_t newlen)
1532 struct ctl_table_header *head;
1533 int error = -ENOTDIR;
1535 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1536 return -ENOTDIR;
1537 if (oldval) {
1538 int old_len;
1539 if (!oldlenp || get_user(old_len, oldlenp))
1540 return -EFAULT;
1543 for (head = sysctl_head_next(NULL); head;
1544 head = sysctl_head_next(head)) {
1545 error = parse_table(name, nlen, oldval, oldlenp,
1546 newval, newlen,
1547 head->root, head->ctl_table);
1548 if (error != -ENOTDIR) {
1549 sysctl_head_finish(head);
1550 break;
1553 return error;
1556 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1558 struct __sysctl_args tmp;
1559 int error;
1561 if (copy_from_user(&tmp, args, sizeof(tmp)))
1562 return -EFAULT;
1564 error = deprecated_sysctl_warning(&tmp);
1565 if (error)
1566 goto out;
1568 lock_kernel();
1569 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1570 tmp.newval, tmp.newlen);
1571 unlock_kernel();
1572 out:
1573 return error;
1575 #endif /* CONFIG_SYSCTL_SYSCALL */
1578 * sysctl_perm does NOT grant the superuser all rights automatically, because
1579 * some sysctl variables are readonly even to root.
1582 static int test_perm(int mode, int op)
1584 if (!current->euid)
1585 mode >>= 6;
1586 else if (in_egroup_p(0))
1587 mode >>= 3;
1588 if ((mode & op & 0007) == op)
1589 return 0;
1590 return -EACCES;
1593 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1595 int error;
1596 int mode;
1598 error = security_sysctl(table, op);
1599 if (error)
1600 return error;
1602 if (root->permissions)
1603 mode = root->permissions(root, current->nsproxy, table);
1604 else
1605 mode = table->mode;
1607 return test_perm(mode, op);
1610 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1612 for (; table->ctl_name || table->procname; table++) {
1613 table->parent = parent;
1614 if (table->child)
1615 sysctl_set_parent(table, table->child);
1619 static __init int sysctl_init(void)
1621 sysctl_set_parent(NULL, root_table);
1622 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1624 int err;
1625 err = sysctl_check_table(current->nsproxy, root_table);
1627 #endif
1628 return 0;
1631 core_initcall(sysctl_init);
1634 * __register_sysctl_paths - register a sysctl hierarchy
1635 * @root: List of sysctl headers to register on
1636 * @namespaces: Data to compute which lists of sysctl entries are visible
1637 * @path: The path to the directory the sysctl table is in.
1638 * @table: the top-level table structure
1640 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1641 * array. A completely 0 filled entry terminates the table.
1643 * The members of the &struct ctl_table structure are used as follows:
1645 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1646 * must be unique within that level of sysctl
1648 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1649 * enter a sysctl file
1651 * data - a pointer to data for use by proc_handler
1653 * maxlen - the maximum size in bytes of the data
1655 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1657 * child - a pointer to the child sysctl table if this entry is a directory, or
1658 * %NULL.
1660 * proc_handler - the text handler routine (described below)
1662 * strategy - the strategy routine (described below)
1664 * de - for internal use by the sysctl routines
1666 * extra1, extra2 - extra pointers usable by the proc handler routines
1668 * Leaf nodes in the sysctl tree will be represented by a single file
1669 * under /proc; non-leaf nodes will be represented by directories.
1671 * sysctl(2) can automatically manage read and write requests through
1672 * the sysctl table. The data and maxlen fields of the ctl_table
1673 * struct enable minimal validation of the values being written to be
1674 * performed, and the mode field allows minimal authentication.
1676 * More sophisticated management can be enabled by the provision of a
1677 * strategy routine with the table entry. This will be called before
1678 * any automatic read or write of the data is performed.
1680 * The strategy routine may return
1682 * < 0 - Error occurred (error is passed to user process)
1684 * 0 - OK - proceed with automatic read or write.
1686 * > 0 - OK - read or write has been done by the strategy routine, so
1687 * return immediately.
1689 * There must be a proc_handler routine for any terminal nodes
1690 * mirrored under /proc/sys (non-terminals are handled by a built-in
1691 * directory handler). Several default handlers are available to
1692 * cover common cases -
1694 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1695 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1696 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1698 * It is the handler's job to read the input buffer from user memory
1699 * and process it. The handler should return 0 on success.
1701 * This routine returns %NULL on a failure to register, and a pointer
1702 * to the table header on success.
1704 struct ctl_table_header *__register_sysctl_paths(
1705 struct ctl_table_root *root,
1706 struct nsproxy *namespaces,
1707 const struct ctl_path *path, struct ctl_table *table)
1709 struct list_head *header_list;
1710 struct ctl_table_header *header;
1711 struct ctl_table *new, **prevp;
1712 unsigned int n, npath;
1714 /* Count the path components */
1715 for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
1719 * For each path component, allocate a 2-element ctl_table array.
1720 * The first array element will be filled with the sysctl entry
1721 * for this, the second will be the sentinel (ctl_name == 0).
1723 * We allocate everything in one go so that we don't have to
1724 * worry about freeing additional memory in unregister_sysctl_table.
1726 header = kzalloc(sizeof(struct ctl_table_header) +
1727 (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
1728 if (!header)
1729 return NULL;
1731 new = (struct ctl_table *) (header + 1);
1733 /* Now connect the dots */
1734 prevp = &header->ctl_table;
1735 for (n = 0; n < npath; ++n, ++path) {
1736 /* Copy the procname */
1737 new->procname = path->procname;
1738 new->ctl_name = path->ctl_name;
1739 new->mode = 0555;
1741 *prevp = new;
1742 prevp = &new->child;
1744 new += 2;
1746 *prevp = table;
1747 header->ctl_table_arg = table;
1749 INIT_LIST_HEAD(&header->ctl_entry);
1750 header->used = 0;
1751 header->unregistering = NULL;
1752 header->root = root;
1753 sysctl_set_parent(NULL, header->ctl_table);
1754 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1755 if (sysctl_check_table(namespaces, header->ctl_table)) {
1756 kfree(header);
1757 return NULL;
1759 #endif
1760 spin_lock(&sysctl_lock);
1761 header_list = lookup_header_list(root, namespaces);
1762 list_add_tail(&header->ctl_entry, header_list);
1763 spin_unlock(&sysctl_lock);
1765 return header;
1769 * register_sysctl_table_path - register a sysctl table hierarchy
1770 * @path: The path to the directory the sysctl table is in.
1771 * @table: the top-level table structure
1773 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1774 * array. A completely 0 filled entry terminates the table.
1776 * See __register_sysctl_paths for more details.
1778 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1779 struct ctl_table *table)
1781 return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
1782 path, table);
1786 * register_sysctl_table - register a sysctl table hierarchy
1787 * @table: the top-level table structure
1789 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1790 * array. A completely 0 filled entry terminates the table.
1792 * See register_sysctl_paths for more details.
1794 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
1796 static const struct ctl_path null_path[] = { {} };
1798 return register_sysctl_paths(null_path, table);
1802 * unregister_sysctl_table - unregister a sysctl table hierarchy
1803 * @header: the header returned from register_sysctl_table
1805 * Unregisters the sysctl table and all children. proc entries may not
1806 * actually be removed until they are no longer used by anyone.
1808 void unregister_sysctl_table(struct ctl_table_header * header)
1810 might_sleep();
1812 if (header == NULL)
1813 return;
1815 spin_lock(&sysctl_lock);
1816 start_unregistering(header);
1817 spin_unlock(&sysctl_lock);
1818 kfree(header);
1821 #else /* !CONFIG_SYSCTL */
1822 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
1824 return NULL;
1827 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1828 struct ctl_table *table)
1830 return NULL;
1833 void unregister_sysctl_table(struct ctl_table_header * table)
1837 #endif /* CONFIG_SYSCTL */
1840 * /proc/sys support
1843 #ifdef CONFIG_PROC_SYSCTL
1845 static int _proc_do_string(void* data, int maxlen, int write,
1846 struct file *filp, void __user *buffer,
1847 size_t *lenp, loff_t *ppos)
1849 size_t len;
1850 char __user *p;
1851 char c;
1853 if (!data || !maxlen || !*lenp) {
1854 *lenp = 0;
1855 return 0;
1858 if (write) {
1859 len = 0;
1860 p = buffer;
1861 while (len < *lenp) {
1862 if (get_user(c, p++))
1863 return -EFAULT;
1864 if (c == 0 || c == '\n')
1865 break;
1866 len++;
1868 if (len >= maxlen)
1869 len = maxlen-1;
1870 if(copy_from_user(data, buffer, len))
1871 return -EFAULT;
1872 ((char *) data)[len] = 0;
1873 *ppos += *lenp;
1874 } else {
1875 len = strlen(data);
1876 if (len > maxlen)
1877 len = maxlen;
1879 if (*ppos > len) {
1880 *lenp = 0;
1881 return 0;
1884 data += *ppos;
1885 len -= *ppos;
1887 if (len > *lenp)
1888 len = *lenp;
1889 if (len)
1890 if(copy_to_user(buffer, data, len))
1891 return -EFAULT;
1892 if (len < *lenp) {
1893 if(put_user('\n', ((char __user *) buffer) + len))
1894 return -EFAULT;
1895 len++;
1897 *lenp = len;
1898 *ppos += len;
1900 return 0;
1904 * proc_dostring - read a string sysctl
1905 * @table: the sysctl table
1906 * @write: %TRUE if this is a write to the sysctl file
1907 * @filp: the file structure
1908 * @buffer: the user buffer
1909 * @lenp: the size of the user buffer
1910 * @ppos: file position
1912 * Reads/writes a string from/to the user buffer. If the kernel
1913 * buffer provided is not large enough to hold the string, the
1914 * string is truncated. The copied string is %NULL-terminated.
1915 * If the string is being read by the user process, it is copied
1916 * and a newline '\n' is added. It is truncated if the buffer is
1917 * not large enough.
1919 * Returns 0 on success.
1921 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
1922 void __user *buffer, size_t *lenp, loff_t *ppos)
1924 return _proc_do_string(table->data, table->maxlen, write, filp,
1925 buffer, lenp, ppos);
1929 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1930 int *valp,
1931 int write, void *data)
1933 if (write) {
1934 *valp = *negp ? -*lvalp : *lvalp;
1935 } else {
1936 int val = *valp;
1937 if (val < 0) {
1938 *negp = -1;
1939 *lvalp = (unsigned long)-val;
1940 } else {
1941 *negp = 0;
1942 *lvalp = (unsigned long)val;
1945 return 0;
1948 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
1949 int write, struct file *filp, void __user *buffer,
1950 size_t *lenp, loff_t *ppos,
1951 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1952 int write, void *data),
1953 void *data)
1955 #define TMPBUFLEN 21
1956 int *i, vleft, first=1, neg, val;
1957 unsigned long lval;
1958 size_t left, len;
1960 char buf[TMPBUFLEN], *p;
1961 char __user *s = buffer;
1963 if (!tbl_data || !table->maxlen || !*lenp ||
1964 (*ppos && !write)) {
1965 *lenp = 0;
1966 return 0;
1969 i = (int *) tbl_data;
1970 vleft = table->maxlen / sizeof(*i);
1971 left = *lenp;
1973 if (!conv)
1974 conv = do_proc_dointvec_conv;
1976 for (; left && vleft--; i++, first=0) {
1977 if (write) {
1978 while (left) {
1979 char c;
1980 if (get_user(c, s))
1981 return -EFAULT;
1982 if (!isspace(c))
1983 break;
1984 left--;
1985 s++;
1987 if (!left)
1988 break;
1989 neg = 0;
1990 len = left;
1991 if (len > sizeof(buf) - 1)
1992 len = sizeof(buf) - 1;
1993 if (copy_from_user(buf, s, len))
1994 return -EFAULT;
1995 buf[len] = 0;
1996 p = buf;
1997 if (*p == '-' && left > 1) {
1998 neg = 1;
1999 p++;
2001 if (*p < '0' || *p > '9')
2002 break;
2004 lval = simple_strtoul(p, &p, 0);
2006 len = p-buf;
2007 if ((len < left) && *p && !isspace(*p))
2008 break;
2009 if (neg)
2010 val = -val;
2011 s += len;
2012 left -= len;
2014 if (conv(&neg, &lval, i, 1, data))
2015 break;
2016 } else {
2017 p = buf;
2018 if (!first)
2019 *p++ = '\t';
2021 if (conv(&neg, &lval, i, 0, data))
2022 break;
2024 sprintf(p, "%s%lu", neg ? "-" : "", lval);
2025 len = strlen(buf);
2026 if (len > left)
2027 len = left;
2028 if(copy_to_user(s, buf, len))
2029 return -EFAULT;
2030 left -= len;
2031 s += len;
2035 if (!write && !first && left) {
2036 if(put_user('\n', s))
2037 return -EFAULT;
2038 left--, s++;
2040 if (write) {
2041 while (left) {
2042 char c;
2043 if (get_user(c, s++))
2044 return -EFAULT;
2045 if (!isspace(c))
2046 break;
2047 left--;
2050 if (write && first)
2051 return -EINVAL;
2052 *lenp -= left;
2053 *ppos += *lenp;
2054 return 0;
2055 #undef TMPBUFLEN
2058 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2059 void __user *buffer, size_t *lenp, loff_t *ppos,
2060 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2061 int write, void *data),
2062 void *data)
2064 return __do_proc_dointvec(table->data, table, write, filp,
2065 buffer, lenp, ppos, conv, data);
2069 * proc_dointvec - read a vector of integers
2070 * @table: the sysctl table
2071 * @write: %TRUE if this is a write to the sysctl file
2072 * @filp: the file structure
2073 * @buffer: the user buffer
2074 * @lenp: the size of the user buffer
2075 * @ppos: file position
2077 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2078 * values from/to the user buffer, treated as an ASCII string.
2080 * Returns 0 on success.
2082 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2083 void __user *buffer, size_t *lenp, loff_t *ppos)
2085 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2086 NULL,NULL);
2089 #define OP_SET 0
2090 #define OP_AND 1
2091 #define OP_OR 2
2093 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
2094 int *valp,
2095 int write, void *data)
2097 int op = *(int *)data;
2098 if (write) {
2099 int val = *negp ? -*lvalp : *lvalp;
2100 switch(op) {
2101 case OP_SET: *valp = val; break;
2102 case OP_AND: *valp &= val; break;
2103 case OP_OR: *valp |= val; break;
2105 } else {
2106 int val = *valp;
2107 if (val < 0) {
2108 *negp = -1;
2109 *lvalp = (unsigned long)-val;
2110 } else {
2111 *negp = 0;
2112 *lvalp = (unsigned long)val;
2115 return 0;
2119 * Taint values can only be increased
2121 static int proc_dointvec_taint(struct ctl_table *table, int write, struct file *filp,
2122 void __user *buffer, size_t *lenp, loff_t *ppos)
2124 int op;
2126 if (write && !capable(CAP_SYS_ADMIN))
2127 return -EPERM;
2129 op = OP_OR;
2130 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2131 do_proc_dointvec_bset_conv,&op);
2134 struct do_proc_dointvec_minmax_conv_param {
2135 int *min;
2136 int *max;
2139 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2140 int *valp,
2141 int write, void *data)
2143 struct do_proc_dointvec_minmax_conv_param *param = data;
2144 if (write) {
2145 int val = *negp ? -*lvalp : *lvalp;
2146 if ((param->min && *param->min > val) ||
2147 (param->max && *param->max < val))
2148 return -EINVAL;
2149 *valp = val;
2150 } else {
2151 int val = *valp;
2152 if (val < 0) {
2153 *negp = -1;
2154 *lvalp = (unsigned long)-val;
2155 } else {
2156 *negp = 0;
2157 *lvalp = (unsigned long)val;
2160 return 0;
2164 * proc_dointvec_minmax - read a vector of integers with min/max values
2165 * @table: the sysctl table
2166 * @write: %TRUE if this is a write to the sysctl file
2167 * @filp: the file structure
2168 * @buffer: the user buffer
2169 * @lenp: the size of the user buffer
2170 * @ppos: file position
2172 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2173 * values from/to the user buffer, treated as an ASCII string.
2175 * This routine will ensure the values are within the range specified by
2176 * table->extra1 (min) and table->extra2 (max).
2178 * Returns 0 on success.
2180 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2181 void __user *buffer, size_t *lenp, loff_t *ppos)
2183 struct do_proc_dointvec_minmax_conv_param param = {
2184 .min = (int *) table->extra1,
2185 .max = (int *) table->extra2,
2187 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2188 do_proc_dointvec_minmax_conv, &param);
2191 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2192 struct file *filp,
2193 void __user *buffer,
2194 size_t *lenp, loff_t *ppos,
2195 unsigned long convmul,
2196 unsigned long convdiv)
2198 #define TMPBUFLEN 21
2199 unsigned long *i, *min, *max, val;
2200 int vleft, first=1, neg;
2201 size_t len, left;
2202 char buf[TMPBUFLEN], *p;
2203 char __user *s = buffer;
2205 if (!data || !table->maxlen || !*lenp ||
2206 (*ppos && !write)) {
2207 *lenp = 0;
2208 return 0;
2211 i = (unsigned long *) data;
2212 min = (unsigned long *) table->extra1;
2213 max = (unsigned long *) table->extra2;
2214 vleft = table->maxlen / sizeof(unsigned long);
2215 left = *lenp;
2217 for (; left && vleft--; i++, min++, max++, first=0) {
2218 if (write) {
2219 while (left) {
2220 char c;
2221 if (get_user(c, s))
2222 return -EFAULT;
2223 if (!isspace(c))
2224 break;
2225 left--;
2226 s++;
2228 if (!left)
2229 break;
2230 neg = 0;
2231 len = left;
2232 if (len > TMPBUFLEN-1)
2233 len = TMPBUFLEN-1;
2234 if (copy_from_user(buf, s, len))
2235 return -EFAULT;
2236 buf[len] = 0;
2237 p = buf;
2238 if (*p == '-' && left > 1) {
2239 neg = 1;
2240 p++;
2242 if (*p < '0' || *p > '9')
2243 break;
2244 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2245 len = p-buf;
2246 if ((len < left) && *p && !isspace(*p))
2247 break;
2248 if (neg)
2249 val = -val;
2250 s += len;
2251 left -= len;
2253 if(neg)
2254 continue;
2255 if ((min && val < *min) || (max && val > *max))
2256 continue;
2257 *i = val;
2258 } else {
2259 p = buf;
2260 if (!first)
2261 *p++ = '\t';
2262 sprintf(p, "%lu", convdiv * (*i) / convmul);
2263 len = strlen(buf);
2264 if (len > left)
2265 len = left;
2266 if(copy_to_user(s, buf, len))
2267 return -EFAULT;
2268 left -= len;
2269 s += len;
2273 if (!write && !first && left) {
2274 if(put_user('\n', s))
2275 return -EFAULT;
2276 left--, s++;
2278 if (write) {
2279 while (left) {
2280 char c;
2281 if (get_user(c, s++))
2282 return -EFAULT;
2283 if (!isspace(c))
2284 break;
2285 left--;
2288 if (write && first)
2289 return -EINVAL;
2290 *lenp -= left;
2291 *ppos += *lenp;
2292 return 0;
2293 #undef TMPBUFLEN
2296 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2297 struct file *filp,
2298 void __user *buffer,
2299 size_t *lenp, loff_t *ppos,
2300 unsigned long convmul,
2301 unsigned long convdiv)
2303 return __do_proc_doulongvec_minmax(table->data, table, write,
2304 filp, buffer, lenp, ppos, convmul, convdiv);
2308 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2309 * @table: the sysctl table
2310 * @write: %TRUE if this is a write to the sysctl file
2311 * @filp: the file structure
2312 * @buffer: the user buffer
2313 * @lenp: the size of the user buffer
2314 * @ppos: file position
2316 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2317 * values from/to the user buffer, treated as an ASCII string.
2319 * This routine will ensure the values are within the range specified by
2320 * table->extra1 (min) and table->extra2 (max).
2322 * Returns 0 on success.
2324 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2325 void __user *buffer, size_t *lenp, loff_t *ppos)
2327 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2331 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2332 * @table: the sysctl table
2333 * @write: %TRUE if this is a write to the sysctl file
2334 * @filp: the file structure
2335 * @buffer: the user buffer
2336 * @lenp: the size of the user buffer
2337 * @ppos: file position
2339 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2340 * values from/to the user buffer, treated as an ASCII string. The values
2341 * are treated as milliseconds, and converted to jiffies when they are stored.
2343 * This routine will ensure the values are within the range specified by
2344 * table->extra1 (min) and table->extra2 (max).
2346 * Returns 0 on success.
2348 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2349 struct file *filp,
2350 void __user *buffer,
2351 size_t *lenp, loff_t *ppos)
2353 return do_proc_doulongvec_minmax(table, write, filp, buffer,
2354 lenp, ppos, HZ, 1000l);
2358 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2359 int *valp,
2360 int write, void *data)
2362 if (write) {
2363 if (*lvalp > LONG_MAX / HZ)
2364 return 1;
2365 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2366 } else {
2367 int val = *valp;
2368 unsigned long lval;
2369 if (val < 0) {
2370 *negp = -1;
2371 lval = (unsigned long)-val;
2372 } else {
2373 *negp = 0;
2374 lval = (unsigned long)val;
2376 *lvalp = lval / HZ;
2378 return 0;
2381 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2382 int *valp,
2383 int write, void *data)
2385 if (write) {
2386 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2387 return 1;
2388 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2389 } else {
2390 int val = *valp;
2391 unsigned long lval;
2392 if (val < 0) {
2393 *negp = -1;
2394 lval = (unsigned long)-val;
2395 } else {
2396 *negp = 0;
2397 lval = (unsigned long)val;
2399 *lvalp = jiffies_to_clock_t(lval);
2401 return 0;
2404 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2405 int *valp,
2406 int write, void *data)
2408 if (write) {
2409 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2410 } else {
2411 int val = *valp;
2412 unsigned long lval;
2413 if (val < 0) {
2414 *negp = -1;
2415 lval = (unsigned long)-val;
2416 } else {
2417 *negp = 0;
2418 lval = (unsigned long)val;
2420 *lvalp = jiffies_to_msecs(lval);
2422 return 0;
2426 * proc_dointvec_jiffies - read a vector of integers as seconds
2427 * @table: the sysctl table
2428 * @write: %TRUE if this is a write to the sysctl file
2429 * @filp: the file structure
2430 * @buffer: the user buffer
2431 * @lenp: the size of the user buffer
2432 * @ppos: file position
2434 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2435 * values from/to the user buffer, treated as an ASCII string.
2436 * The values read are assumed to be in seconds, and are converted into
2437 * jiffies.
2439 * Returns 0 on success.
2441 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2442 void __user *buffer, size_t *lenp, loff_t *ppos)
2444 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2445 do_proc_dointvec_jiffies_conv,NULL);
2449 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2450 * @table: the sysctl table
2451 * @write: %TRUE if this is a write to the sysctl file
2452 * @filp: the file structure
2453 * @buffer: the user buffer
2454 * @lenp: the size of the user buffer
2455 * @ppos: pointer to the file position
2457 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2458 * values from/to the user buffer, treated as an ASCII string.
2459 * The values read are assumed to be in 1/USER_HZ seconds, and
2460 * are converted into jiffies.
2462 * Returns 0 on success.
2464 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2465 void __user *buffer, size_t *lenp, loff_t *ppos)
2467 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2468 do_proc_dointvec_userhz_jiffies_conv,NULL);
2472 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2473 * @table: the sysctl table
2474 * @write: %TRUE if this is a write to the sysctl file
2475 * @filp: the file structure
2476 * @buffer: the user buffer
2477 * @lenp: the size of the user buffer
2478 * @ppos: file position
2479 * @ppos: the current position in the file
2481 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2482 * values from/to the user buffer, treated as an ASCII string.
2483 * The values read are assumed to be in 1/1000 seconds, and
2484 * are converted into jiffies.
2486 * Returns 0 on success.
2488 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2489 void __user *buffer, size_t *lenp, loff_t *ppos)
2491 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2492 do_proc_dointvec_ms_jiffies_conv, NULL);
2495 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2496 void __user *buffer, size_t *lenp, loff_t *ppos)
2498 struct pid *new_pid;
2499 pid_t tmp;
2500 int r;
2502 tmp = pid_vnr(cad_pid);
2504 r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2505 lenp, ppos, NULL, NULL);
2506 if (r || !write)
2507 return r;
2509 new_pid = find_get_pid(tmp);
2510 if (!new_pid)
2511 return -ESRCH;
2513 put_pid(xchg(&cad_pid, new_pid));
2514 return 0;
2517 #else /* CONFIG_PROC_FS */
2519 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2520 void __user *buffer, size_t *lenp, loff_t *ppos)
2522 return -ENOSYS;
2525 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2526 void __user *buffer, size_t *lenp, loff_t *ppos)
2528 return -ENOSYS;
2531 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2532 void __user *buffer, size_t *lenp, loff_t *ppos)
2534 return -ENOSYS;
2537 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2538 void __user *buffer, size_t *lenp, loff_t *ppos)
2540 return -ENOSYS;
2543 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2544 void __user *buffer, size_t *lenp, loff_t *ppos)
2546 return -ENOSYS;
2549 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2550 void __user *buffer, size_t *lenp, loff_t *ppos)
2552 return -ENOSYS;
2555 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2556 void __user *buffer, size_t *lenp, loff_t *ppos)
2558 return -ENOSYS;
2561 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2562 struct file *filp,
2563 void __user *buffer,
2564 size_t *lenp, loff_t *ppos)
2566 return -ENOSYS;
2570 #endif /* CONFIG_PROC_FS */
2573 #ifdef CONFIG_SYSCTL_SYSCALL
2575 * General sysctl support routines
2578 /* The generic sysctl data routine (used if no strategy routine supplied) */
2579 int sysctl_data(struct ctl_table *table, int __user *name, int nlen,
2580 void __user *oldval, size_t __user *oldlenp,
2581 void __user *newval, size_t newlen)
2583 size_t len;
2585 /* Get out of I don't have a variable */
2586 if (!table->data || !table->maxlen)
2587 return -ENOTDIR;
2589 if (oldval && oldlenp) {
2590 if (get_user(len, oldlenp))
2591 return -EFAULT;
2592 if (len) {
2593 if (len > table->maxlen)
2594 len = table->maxlen;
2595 if (copy_to_user(oldval, table->data, len))
2596 return -EFAULT;
2597 if (put_user(len, oldlenp))
2598 return -EFAULT;
2602 if (newval && newlen) {
2603 if (newlen > table->maxlen)
2604 newlen = table->maxlen;
2606 if (copy_from_user(table->data, newval, newlen))
2607 return -EFAULT;
2609 return 1;
2612 /* The generic string strategy routine: */
2613 int sysctl_string(struct ctl_table *table, int __user *name, int nlen,
2614 void __user *oldval, size_t __user *oldlenp,
2615 void __user *newval, size_t newlen)
2617 if (!table->data || !table->maxlen)
2618 return -ENOTDIR;
2620 if (oldval && oldlenp) {
2621 size_t bufsize;
2622 if (get_user(bufsize, oldlenp))
2623 return -EFAULT;
2624 if (bufsize) {
2625 size_t len = strlen(table->data), copied;
2627 /* This shouldn't trigger for a well-formed sysctl */
2628 if (len > table->maxlen)
2629 len = table->maxlen;
2631 /* Copy up to a max of bufsize-1 bytes of the string */
2632 copied = (len >= bufsize) ? bufsize - 1 : len;
2634 if (copy_to_user(oldval, table->data, copied) ||
2635 put_user(0, (char __user *)(oldval + copied)))
2636 return -EFAULT;
2637 if (put_user(len, oldlenp))
2638 return -EFAULT;
2641 if (newval && newlen) {
2642 size_t len = newlen;
2643 if (len > table->maxlen)
2644 len = table->maxlen;
2645 if(copy_from_user(table->data, newval, len))
2646 return -EFAULT;
2647 if (len == table->maxlen)
2648 len--;
2649 ((char *) table->data)[len] = 0;
2651 return 1;
2655 * This function makes sure that all of the integers in the vector
2656 * are between the minimum and maximum values given in the arrays
2657 * table->extra1 and table->extra2, respectively.
2659 int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen,
2660 void __user *oldval, size_t __user *oldlenp,
2661 void __user *newval, size_t newlen)
2664 if (newval && newlen) {
2665 int __user *vec = (int __user *) newval;
2666 int *min = (int *) table->extra1;
2667 int *max = (int *) table->extra2;
2668 size_t length;
2669 int i;
2671 if (newlen % sizeof(int) != 0)
2672 return -EINVAL;
2674 if (!table->extra1 && !table->extra2)
2675 return 0;
2677 if (newlen > table->maxlen)
2678 newlen = table->maxlen;
2679 length = newlen / sizeof(int);
2681 for (i = 0; i < length; i++) {
2682 int value;
2683 if (get_user(value, vec + i))
2684 return -EFAULT;
2685 if (min && value < min[i])
2686 return -EINVAL;
2687 if (max && value > max[i])
2688 return -EINVAL;
2691 return 0;
2694 /* Strategy function to convert jiffies to seconds */
2695 int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen,
2696 void __user *oldval, size_t __user *oldlenp,
2697 void __user *newval, size_t newlen)
2699 if (oldval && oldlenp) {
2700 size_t olen;
2702 if (get_user(olen, oldlenp))
2703 return -EFAULT;
2704 if (olen) {
2705 int val;
2707 if (olen < sizeof(int))
2708 return -EINVAL;
2710 val = *(int *)(table->data) / HZ;
2711 if (put_user(val, (int __user *)oldval))
2712 return -EFAULT;
2713 if (put_user(sizeof(int), oldlenp))
2714 return -EFAULT;
2717 if (newval && newlen) {
2718 int new;
2719 if (newlen != sizeof(int))
2720 return -EINVAL;
2721 if (get_user(new, (int __user *)newval))
2722 return -EFAULT;
2723 *(int *)(table->data) = new*HZ;
2725 return 1;
2728 /* Strategy function to convert jiffies to seconds */
2729 int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen,
2730 void __user *oldval, size_t __user *oldlenp,
2731 void __user *newval, size_t newlen)
2733 if (oldval && oldlenp) {
2734 size_t olen;
2736 if (get_user(olen, oldlenp))
2737 return -EFAULT;
2738 if (olen) {
2739 int val;
2741 if (olen < sizeof(int))
2742 return -EINVAL;
2744 val = jiffies_to_msecs(*(int *)(table->data));
2745 if (put_user(val, (int __user *)oldval))
2746 return -EFAULT;
2747 if (put_user(sizeof(int), oldlenp))
2748 return -EFAULT;
2751 if (newval && newlen) {
2752 int new;
2753 if (newlen != sizeof(int))
2754 return -EINVAL;
2755 if (get_user(new, (int __user *)newval))
2756 return -EFAULT;
2757 *(int *)(table->data) = msecs_to_jiffies(new);
2759 return 1;
2764 #else /* CONFIG_SYSCTL_SYSCALL */
2767 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2769 struct __sysctl_args tmp;
2770 int error;
2772 if (copy_from_user(&tmp, args, sizeof(tmp)))
2773 return -EFAULT;
2775 error = deprecated_sysctl_warning(&tmp);
2777 /* If no error reading the parameters then just -ENOSYS ... */
2778 if (!error)
2779 error = -ENOSYS;
2781 return error;
2784 int sysctl_data(struct ctl_table *table, int __user *name, int nlen,
2785 void __user *oldval, size_t __user *oldlenp,
2786 void __user *newval, size_t newlen)
2788 return -ENOSYS;
2791 int sysctl_string(struct ctl_table *table, int __user *name, int nlen,
2792 void __user *oldval, size_t __user *oldlenp,
2793 void __user *newval, size_t newlen)
2795 return -ENOSYS;
2798 int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen,
2799 void __user *oldval, size_t __user *oldlenp,
2800 void __user *newval, size_t newlen)
2802 return -ENOSYS;
2805 int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen,
2806 void __user *oldval, size_t __user *oldlenp,
2807 void __user *newval, size_t newlen)
2809 return -ENOSYS;
2812 int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen,
2813 void __user *oldval, size_t __user *oldlenp,
2814 void __user *newval, size_t newlen)
2816 return -ENOSYS;
2819 #endif /* CONFIG_SYSCTL_SYSCALL */
2821 static int deprecated_sysctl_warning(struct __sysctl_args *args)
2823 static int msg_count;
2824 int name[CTL_MAXNAME];
2825 int i;
2827 /* Check args->nlen. */
2828 if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
2829 return -ENOTDIR;
2831 /* Read in the sysctl name for better debug message logging */
2832 for (i = 0; i < args->nlen; i++)
2833 if (get_user(name[i], args->name + i))
2834 return -EFAULT;
2836 /* Ignore accesses to kernel.version */
2837 if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
2838 return 0;
2840 if (msg_count < 5) {
2841 msg_count++;
2842 printk(KERN_INFO
2843 "warning: process `%s' used the deprecated sysctl "
2844 "system call with ", current->comm);
2845 for (i = 0; i < args->nlen; i++)
2846 printk("%d.", name[i]);
2847 printk("\n");
2849 return 0;
2853 * No sense putting this after each symbol definition, twice,
2854 * exception granted :-)
2856 EXPORT_SYMBOL(proc_dointvec);
2857 EXPORT_SYMBOL(proc_dointvec_jiffies);
2858 EXPORT_SYMBOL(proc_dointvec_minmax);
2859 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2860 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2861 EXPORT_SYMBOL(proc_dostring);
2862 EXPORT_SYMBOL(proc_doulongvec_minmax);
2863 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2864 EXPORT_SYMBOL(register_sysctl_table);
2865 EXPORT_SYMBOL(register_sysctl_paths);
2866 EXPORT_SYMBOL(sysctl_intvec);
2867 EXPORT_SYMBOL(sysctl_jiffies);
2868 EXPORT_SYMBOL(sysctl_ms_jiffies);
2869 EXPORT_SYMBOL(sysctl_string);
2870 EXPORT_SYMBOL(sysctl_data);
2871 EXPORT_SYMBOL(unregister_sysctl_table);