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Create the ZONE_MOVABLE zone
[linux-2.6/mini2440.git] / kernel / sysctl.c
blob2ce7acf841aefede15e0304ef09865484c0cb07e
1 /*
2 * sysctl.c: General linux system control interface
3 *
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
19 */
20
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/capability.h>
31 #include <linux/smp_lock.h>
32 #include <linux/init.h>
33 #include <linux/kernel.h>
34 #include <linux/kobject.h>
35 #include <linux/net.h>
36 #include <linux/sysrq.h>
37 #include <linux/highuid.h>
38 #include <linux/writeback.h>
39 #include <linux/hugetlb.h>
40 #include <linux/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
49 #include <asm/uaccess.h>
50 #include <asm/processor.h>
51
52 extern int proc_nr_files(ctl_table *table, int write, struct file *filp,
53 void __user *buffer, size_t *lenp, loff_t *ppos);
54
55 #ifdef CONFIG_X86
56 #include <asm/nmi.h>
57 #include <asm/stacktrace.h>
58 #endif
59
60 #if defined(CONFIG_SYSCTL)
61
62 /* External variables not in a header file. */
63 extern int C_A_D;
64 extern int print_fatal_signals;
65 extern int sysctl_overcommit_memory;
66 extern int sysctl_overcommit_ratio;
67 extern int sysctl_panic_on_oom;
68 extern int max_threads;
69 extern int core_uses_pid;
70 extern int suid_dumpable;
71 extern char core_pattern[];
72 extern int pid_max;
73 extern int min_free_kbytes;
74 extern int printk_ratelimit_jiffies;
75 extern int printk_ratelimit_burst;
76 extern int pid_max_min, pid_max_max;
77 extern int sysctl_drop_caches;
78 extern int percpu_pagelist_fraction;
79 extern int compat_log;
80 extern int maps_protect;
81 extern int sysctl_stat_interval;
82
83 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
84 static int maxolduid = 65535;
85 static int minolduid;
86 static int min_percpu_pagelist_fract = 8;
87
88 static int ngroups_max = NGROUPS_MAX;
89
90 #ifdef CONFIG_KMOD
91 extern char modprobe_path[];
92 #endif
93 #ifdef CONFIG_CHR_DEV_SG
94 extern int sg_big_buff;
95 #endif
96
97 #ifdef __sparc__
98 extern char reboot_command [];
99 extern int stop_a_enabled;
100 extern int scons_pwroff;
101 #endif
102
103 #ifdef __hppa__
104 extern int pwrsw_enabled;
105 extern int unaligned_enabled;
106 #endif
107
108 #ifdef CONFIG_S390
109 #ifdef CONFIG_MATHEMU
110 extern int sysctl_ieee_emulation_warnings;
111 #endif
112 extern int sysctl_userprocess_debug;
113 extern int spin_retry;
114 #endif
115
116 extern int sysctl_hz_timer;
117
118 #ifdef CONFIG_BSD_PROCESS_ACCT
119 extern int acct_parm[];
120 #endif
121
122 #ifdef CONFIG_IA64
123 extern int no_unaligned_warning;
124 #endif
125
126 #ifdef CONFIG_RT_MUTEXES
127 extern int max_lock_depth;
128 #endif
129
130 #ifdef CONFIG_SYSCTL_SYSCALL
131 static int parse_table(int __user *, int, void __user *, size_t __user *,
132 void __user *, size_t, ctl_table *);
133 #endif
134
135
136 #ifdef CONFIG_PROC_SYSCTL
137 static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
138 void __user *buffer, size_t *lenp, loff_t *ppos);
139 static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
140 void __user *buffer, size_t *lenp, loff_t *ppos);
141 #endif
142
143 static ctl_table root_table[];
144 static struct ctl_table_header root_table_header =
145 { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
146
147 static ctl_table kern_table[];
148 static ctl_table vm_table[];
149 static ctl_table fs_table[];
150 static ctl_table debug_table[];
151 static ctl_table dev_table[];
152 extern ctl_table random_table[];
153 #ifdef CONFIG_UNIX98_PTYS
154 extern ctl_table pty_table[];
155 #endif
156 #ifdef CONFIG_INOTIFY_USER
157 extern ctl_table inotify_table[];
158 #endif
159
160 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
161 int sysctl_legacy_va_layout;
162 #endif
163
164
165 /* The default sysctl tables: */
166
167 static ctl_table root_table[] = {
168 {
169 .ctl_name = CTL_KERN,
170 .procname = "kernel",
171 .mode = 0555,
172 .child = kern_table,
173 },
174 {
175 .ctl_name = CTL_VM,
176 .procname = "vm",
177 .mode = 0555,
178 .child = vm_table,
179 },
180 #ifdef CONFIG_NET
181 {
182 .ctl_name = CTL_NET,
183 .procname = "net",
184 .mode = 0555,
185 .child = net_table,
186 },
187 #endif
188 {
189 .ctl_name = CTL_FS,
190 .procname = "fs",
191 .mode = 0555,
192 .child = fs_table,
193 },
194 {
195 .ctl_name = CTL_DEBUG,
196 .procname = "debug",
197 .mode = 0555,
198 .child = debug_table,
199 },
200 {
201 .ctl_name = CTL_DEV,
202 .procname = "dev",
203 .mode = 0555,
204 .child = dev_table,
205 },
206 /*
207 * NOTE: do not add new entries to this table unless you have read
208 * Documentation/sysctl/ctl_unnumbered.txt
209 */
210 { .ctl_name = 0 }
211 };
212
213 #ifdef CONFIG_SCHED_DEBUG
214 static unsigned long min_sched_granularity_ns = 100000; /* 100 usecs */
215 static unsigned long max_sched_granularity_ns = 1000000000; /* 1 second */
216 static unsigned long min_wakeup_granularity_ns; /* 0 usecs */
217 static unsigned long max_wakeup_granularity_ns = 1000000000; /* 1 second */
218 #endif
219
220 static ctl_table kern_table[] = {
221 #ifdef CONFIG_SCHED_DEBUG
222 {
223 .ctl_name = CTL_UNNUMBERED,
224 .procname = "sched_granularity_ns",
225 .data = &sysctl_sched_granularity,
226 .maxlen = sizeof(unsigned int),
227 .mode = 0644,
228 .proc_handler = &proc_dointvec_minmax,
229 .strategy = &sysctl_intvec,
230 .extra1 = &min_sched_granularity_ns,
231 .extra2 = &max_sched_granularity_ns,
232 },
233 {
234 .ctl_name = CTL_UNNUMBERED,
235 .procname = "sched_wakeup_granularity_ns",
236 .data = &sysctl_sched_wakeup_granularity,
237 .maxlen = sizeof(unsigned int),
238 .mode = 0644,
239 .proc_handler = &proc_dointvec_minmax,
240 .strategy = &sysctl_intvec,
241 .extra1 = &min_wakeup_granularity_ns,
242 .extra2 = &max_wakeup_granularity_ns,
243 },
244 {
245 .ctl_name = CTL_UNNUMBERED,
246 .procname = "sched_batch_wakeup_granularity_ns",
247 .data = &sysctl_sched_batch_wakeup_granularity,
248 .maxlen = sizeof(unsigned int),
249 .mode = 0644,
250 .proc_handler = &proc_dointvec_minmax,
251 .strategy = &sysctl_intvec,
252 .extra1 = &min_wakeup_granularity_ns,
253 .extra2 = &max_wakeup_granularity_ns,
254 },
255 {
256 .ctl_name = CTL_UNNUMBERED,
257 .procname = "sched_stat_granularity_ns",
258 .data = &sysctl_sched_stat_granularity,
259 .maxlen = sizeof(unsigned int),
260 .mode = 0644,
261 .proc_handler = &proc_dointvec_minmax,
262 .strategy = &sysctl_intvec,
263 .extra1 = &min_wakeup_granularity_ns,
264 .extra2 = &max_wakeup_granularity_ns,
265 },
266 {
267 .ctl_name = CTL_UNNUMBERED,
268 .procname = "sched_runtime_limit_ns",
269 .data = &sysctl_sched_runtime_limit,
270 .maxlen = sizeof(unsigned int),
271 .mode = 0644,
272 .proc_handler = &proc_dointvec_minmax,
273 .strategy = &sysctl_intvec,
274 .extra1 = &min_sched_granularity_ns,
275 .extra2 = &max_sched_granularity_ns,
276 },
277 {
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,
284 },
285 {
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,
292 },
293 #endif
294 {
295 .ctl_name = KERN_PANIC,
296 .procname = "panic",
297 .data = &panic_timeout,
298 .maxlen = sizeof(int),
299 .mode = 0644,
300 .proc_handler = &proc_dointvec,
301 },
302 {
303 .ctl_name = KERN_CORE_USES_PID,
304 .procname = "core_uses_pid",
305 .data = &core_uses_pid,
306 .maxlen = sizeof(int),
307 .mode = 0644,
308 .proc_handler = &proc_dointvec,
309 },
310 {
311 .ctl_name = KERN_CORE_PATTERN,
312 .procname = "core_pattern",
313 .data = core_pattern,
314 .maxlen = CORENAME_MAX_SIZE,
315 .mode = 0644,
316 .proc_handler = &proc_dostring,
317 .strategy = &sysctl_string,
318 },
319 #ifdef CONFIG_PROC_SYSCTL
320 {
321 .ctl_name = KERN_TAINTED,
322 .procname = "tainted",
323 .data = &tainted,
324 .maxlen = sizeof(int),
325 .mode = 0644,
326 .proc_handler = &proc_dointvec_taint,
327 },
328 #endif
329 {
330 .ctl_name = KERN_CAP_BSET,
331 .procname = "cap-bound",
332 .data = &cap_bset,
333 .maxlen = sizeof(kernel_cap_t),
334 .mode = 0600,
335 .proc_handler = &proc_dointvec_bset,
336 },
337 #ifdef CONFIG_BLK_DEV_INITRD
338 {
339 .ctl_name = KERN_REALROOTDEV,
340 .procname = "real-root-dev",
341 .data = &real_root_dev,
342 .maxlen = sizeof(int),
343 .mode = 0644,
344 .proc_handler = &proc_dointvec,
345 },
346 #endif
347 {
348 .ctl_name = CTL_UNNUMBERED,
349 .procname = "print-fatal-signals",
350 .data = &print_fatal_signals,
351 .maxlen = sizeof(int),
352 .mode = 0644,
353 .proc_handler = &proc_dointvec,
354 },
355 #ifdef __sparc__
356 {
357 .ctl_name = KERN_SPARC_REBOOT,
358 .procname = "reboot-cmd",
359 .data = reboot_command,
360 .maxlen = 256,
361 .mode = 0644,
362 .proc_handler = &proc_dostring,
363 .strategy = &sysctl_string,
364 },
365 {
366 .ctl_name = KERN_SPARC_STOP_A,
367 .procname = "stop-a",
368 .data = &stop_a_enabled,
369 .maxlen = sizeof (int),
370 .mode = 0644,
371 .proc_handler = &proc_dointvec,
372 },
373 {
374 .ctl_name = KERN_SPARC_SCONS_PWROFF,
375 .procname = "scons-poweroff",
376 .data = &scons_pwroff,
377 .maxlen = sizeof (int),
378 .mode = 0644,
379 .proc_handler = &proc_dointvec,
380 },
381 #endif
382 #ifdef __hppa__
383 {
384 .ctl_name = KERN_HPPA_PWRSW,
385 .procname = "soft-power",
386 .data = &pwrsw_enabled,
387 .maxlen = sizeof (int),
388 .mode = 0644,
389 .proc_handler = &proc_dointvec,
390 },
391 {
392 .ctl_name = KERN_HPPA_UNALIGNED,
393 .procname = "unaligned-trap",
394 .data = &unaligned_enabled,
395 .maxlen = sizeof (int),
396 .mode = 0644,
397 .proc_handler = &proc_dointvec,
398 },
399 #endif
400 {
401 .ctl_name = KERN_CTLALTDEL,
402 .procname = "ctrl-alt-del",
403 .data = &C_A_D,
404 .maxlen = sizeof(int),
405 .mode = 0644,
406 .proc_handler = &proc_dointvec,
407 },
408 {
409 .ctl_name = KERN_PRINTK,
410 .procname = "printk",
411 .data = &console_loglevel,
412 .maxlen = 4*sizeof(int),
413 .mode = 0644,
414 .proc_handler = &proc_dointvec,
415 },
416 #ifdef CONFIG_KMOD
417 {
418 .ctl_name = KERN_MODPROBE,
419 .procname = "modprobe",
420 .data = &modprobe_path,
421 .maxlen = KMOD_PATH_LEN,
422 .mode = 0644,
423 .proc_handler = &proc_dostring,
424 .strategy = &sysctl_string,
425 },
426 #endif
427 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
428 {
429 .ctl_name = KERN_HOTPLUG,
430 .procname = "hotplug",
431 .data = &uevent_helper,
432 .maxlen = UEVENT_HELPER_PATH_LEN,
433 .mode = 0644,
434 .proc_handler = &proc_dostring,
435 .strategy = &sysctl_string,
436 },
437 #endif
438 #ifdef CONFIG_CHR_DEV_SG
439 {
440 .ctl_name = KERN_SG_BIG_BUFF,
441 .procname = "sg-big-buff",
442 .data = &sg_big_buff,
443 .maxlen = sizeof (int),
444 .mode = 0444,
445 .proc_handler = &proc_dointvec,
446 },
447 #endif
448 #ifdef CONFIG_BSD_PROCESS_ACCT
449 {
450 .ctl_name = KERN_ACCT,
451 .procname = "acct",
452 .data = &acct_parm,
453 .maxlen = 3*sizeof(int),
454 .mode = 0644,
455 .proc_handler = &proc_dointvec,
456 },
457 #endif
458 #ifdef CONFIG_MAGIC_SYSRQ
459 {
460 .ctl_name = KERN_SYSRQ,
461 .procname = "sysrq",
462 .data = &__sysrq_enabled,
463 .maxlen = sizeof (int),
464 .mode = 0644,
465 .proc_handler = &proc_dointvec,
466 },
467 #endif
468 #ifdef CONFIG_PROC_SYSCTL
469 {
470 .ctl_name = KERN_CADPID,
471 .procname = "cad_pid",
472 .data = NULL,
473 .maxlen = sizeof (int),
474 .mode = 0600,
475 .proc_handler = &proc_do_cad_pid,
476 },
477 #endif
478 {
479 .ctl_name = KERN_MAX_THREADS,
480 .procname = "threads-max",
481 .data = &max_threads,
482 .maxlen = sizeof(int),
483 .mode = 0644,
484 .proc_handler = &proc_dointvec,
485 },
486 {
487 .ctl_name = KERN_RANDOM,
488 .procname = "random",
489 .mode = 0555,
490 .child = random_table,
491 },
492 #ifdef CONFIG_UNIX98_PTYS
493 {
494 .ctl_name = KERN_PTY,
495 .procname = "pty",
496 .mode = 0555,
497 .child = pty_table,
498 },
499 #endif
500 {
501 .ctl_name = KERN_OVERFLOWUID,
502 .procname = "overflowuid",
503 .data = &overflowuid,
504 .maxlen = sizeof(int),
505 .mode = 0644,
506 .proc_handler = &proc_dointvec_minmax,
507 .strategy = &sysctl_intvec,
508 .extra1 = &minolduid,
509 .extra2 = &maxolduid,
510 },
511 {
512 .ctl_name = KERN_OVERFLOWGID,
513 .procname = "overflowgid",
514 .data = &overflowgid,
515 .maxlen = sizeof(int),
516 .mode = 0644,
517 .proc_handler = &proc_dointvec_minmax,
518 .strategy = &sysctl_intvec,
519 .extra1 = &minolduid,
520 .extra2 = &maxolduid,
521 },
522 #ifdef CONFIG_S390
523 #ifdef CONFIG_MATHEMU
524 {
525 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
526 .procname = "ieee_emulation_warnings",
527 .data = &sysctl_ieee_emulation_warnings,
528 .maxlen = sizeof(int),
529 .mode = 0644,
530 .proc_handler = &proc_dointvec,
531 },
532 #endif
533 #ifdef CONFIG_NO_IDLE_HZ
534 {
535 .ctl_name = KERN_HZ_TIMER,
536 .procname = "hz_timer",
537 .data = &sysctl_hz_timer,
538 .maxlen = sizeof(int),
539 .mode = 0644,
540 .proc_handler = &proc_dointvec,
541 },
542 #endif
543 {
544 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
545 .procname = "userprocess_debug",
546 .data = &sysctl_userprocess_debug,
547 .maxlen = sizeof(int),
548 .mode = 0644,
549 .proc_handler = &proc_dointvec,
550 },
551 #endif
552 {
553 .ctl_name = KERN_PIDMAX,
554 .procname = "pid_max",
555 .data = &pid_max,
556 .maxlen = sizeof (int),
557 .mode = 0644,
558 .proc_handler = &proc_dointvec_minmax,
559 .strategy = sysctl_intvec,
560 .extra1 = &pid_max_min,
561 .extra2 = &pid_max_max,
562 },
563 {
564 .ctl_name = KERN_PANIC_ON_OOPS,
565 .procname = "panic_on_oops",
566 .data = &panic_on_oops,
567 .maxlen = sizeof(int),
568 .mode = 0644,
569 .proc_handler = &proc_dointvec,
570 },
571 {
572 .ctl_name = KERN_PRINTK_RATELIMIT,
573 .procname = "printk_ratelimit",
574 .data = &printk_ratelimit_jiffies,
575 .maxlen = sizeof(int),
576 .mode = 0644,
577 .proc_handler = &proc_dointvec_jiffies,
578 .strategy = &sysctl_jiffies,
579 },
580 {
581 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
582 .procname = "printk_ratelimit_burst",
583 .data = &printk_ratelimit_burst,
584 .maxlen = sizeof(int),
585 .mode = 0644,
586 .proc_handler = &proc_dointvec,
587 },
588 {
589 .ctl_name = KERN_NGROUPS_MAX,
590 .procname = "ngroups_max",
591 .data = &ngroups_max,
592 .maxlen = sizeof (int),
593 .mode = 0444,
594 .proc_handler = &proc_dointvec,
595 },
596 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
597 {
598 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
599 .procname = "unknown_nmi_panic",
600 .data = &unknown_nmi_panic,
601 .maxlen = sizeof (int),
602 .mode = 0644,
603 .proc_handler = &proc_dointvec,
604 },
605 {
606 .ctl_name = KERN_NMI_WATCHDOG,
607 .procname = "nmi_watchdog",
608 .data = &nmi_watchdog_enabled,
609 .maxlen = sizeof (int),
610 .mode = 0644,
611 .proc_handler = &proc_nmi_enabled,
612 },
613 #endif
614 #if defined(CONFIG_X86)
615 {
616 .ctl_name = KERN_PANIC_ON_NMI,
617 .procname = "panic_on_unrecovered_nmi",
618 .data = &panic_on_unrecovered_nmi,
619 .maxlen = sizeof(int),
620 .mode = 0644,
621 .proc_handler = &proc_dointvec,
622 },
623 {
624 .ctl_name = KERN_BOOTLOADER_TYPE,
625 .procname = "bootloader_type",
626 .data = &bootloader_type,
627 .maxlen = sizeof (int),
628 .mode = 0444,
629 .proc_handler = &proc_dointvec,
630 },
631 {
632 .ctl_name = CTL_UNNUMBERED,
633 .procname = "kstack_depth_to_print",
634 .data = &kstack_depth_to_print,
635 .maxlen = sizeof(int),
636 .mode = 0644,
637 .proc_handler = &proc_dointvec,
638 },
639 #endif
640 #if defined(CONFIG_MMU)
641 {
642 .ctl_name = KERN_RANDOMIZE,
643 .procname = "randomize_va_space",
644 .data = &randomize_va_space,
645 .maxlen = sizeof(int),
646 .mode = 0644,
647 .proc_handler = &proc_dointvec,
648 },
649 #endif
650 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
651 {
652 .ctl_name = KERN_SPIN_RETRY,
653 .procname = "spin_retry",
654 .data = &spin_retry,
655 .maxlen = sizeof (int),
656 .mode = 0644,
657 .proc_handler = &proc_dointvec,
658 },
659 #endif
660 #ifdef CONFIG_ACPI_SLEEP
661 {
662 .ctl_name = KERN_ACPI_VIDEO_FLAGS,
663 .procname = "acpi_video_flags",
664 .data = &acpi_video_flags,
665 .maxlen = sizeof (unsigned long),
666 .mode = 0644,
667 .proc_handler = &proc_doulongvec_minmax,
668 },
669 #endif
670 #ifdef CONFIG_IA64
671 {
672 .ctl_name = KERN_IA64_UNALIGNED,
673 .procname = "ignore-unaligned-usertrap",
674 .data = &no_unaligned_warning,
675 .maxlen = sizeof (int),
676 .mode = 0644,
677 .proc_handler = &proc_dointvec,
678 },
679 #endif
680 #ifdef CONFIG_COMPAT
681 {
682 .ctl_name = KERN_COMPAT_LOG,
683 .procname = "compat-log",
684 .data = &compat_log,
685 .maxlen = sizeof (int),
686 .mode = 0644,
687 .proc_handler = &proc_dointvec,
688 },
689 #endif
690 #ifdef CONFIG_RT_MUTEXES
691 {
692 .ctl_name = KERN_MAX_LOCK_DEPTH,
693 .procname = "max_lock_depth",
694 .data = &max_lock_depth,
695 .maxlen = sizeof(int),
696 .mode = 0644,
697 .proc_handler = &proc_dointvec,
698 },
699 #endif
700 #ifdef CONFIG_PROC_FS
701 {
702 .ctl_name = CTL_UNNUMBERED,
703 .procname = "maps_protect",
704 .data = &maps_protect,
705 .maxlen = sizeof(int),
706 .mode = 0644,
707 .proc_handler = &proc_dointvec,
708 },
709 #endif
710
711 { .ctl_name = 0 }
712 };
713
714 /* Constants for minimum and maximum testing in vm_table.
715 We use these as one-element integer vectors. */
716 static int zero;
717 static int one_hundred = 100;
718
719
720 static ctl_table vm_table[] = {
721 {
722 .ctl_name = VM_OVERCOMMIT_MEMORY,
723 .procname = "overcommit_memory",
724 .data = &sysctl_overcommit_memory,
725 .maxlen = sizeof(sysctl_overcommit_memory),
726 .mode = 0644,
727 .proc_handler = &proc_dointvec,
728 },
729 {
730 .ctl_name = VM_PANIC_ON_OOM,
731 .procname = "panic_on_oom",
732 .data = &sysctl_panic_on_oom,
733 .maxlen = sizeof(sysctl_panic_on_oom),
734 .mode = 0644,
735 .proc_handler = &proc_dointvec,
736 },
737 {
738 .ctl_name = VM_OVERCOMMIT_RATIO,
739 .procname = "overcommit_ratio",
740 .data = &sysctl_overcommit_ratio,
741 .maxlen = sizeof(sysctl_overcommit_ratio),
742 .mode = 0644,
743 .proc_handler = &proc_dointvec,
744 },
745 {
746 .ctl_name = VM_PAGE_CLUSTER,
747 .procname = "page-cluster",
748 .data = &page_cluster,
749 .maxlen = sizeof(int),
750 .mode = 0644,
751 .proc_handler = &proc_dointvec,
752 },
753 {
754 .ctl_name = VM_DIRTY_BACKGROUND,
755 .procname = "dirty_background_ratio",
756 .data = &dirty_background_ratio,
757 .maxlen = sizeof(dirty_background_ratio),
758 .mode = 0644,
759 .proc_handler = &proc_dointvec_minmax,
760 .strategy = &sysctl_intvec,
761 .extra1 = &zero,
762 .extra2 = &one_hundred,
763 },
764 {
765 .ctl_name = VM_DIRTY_RATIO,
766 .procname = "dirty_ratio",
767 .data = &vm_dirty_ratio,
768 .maxlen = sizeof(vm_dirty_ratio),
769 .mode = 0644,
770 .proc_handler = &proc_dointvec_minmax,
771 .strategy = &sysctl_intvec,
772 .extra1 = &zero,
773 .extra2 = &one_hundred,
774 },
775 {
776 .ctl_name = VM_DIRTY_WB_CS,
777 .procname = "dirty_writeback_centisecs",
778 .data = &dirty_writeback_interval,
779 .maxlen = sizeof(dirty_writeback_interval),
780 .mode = 0644,
781 .proc_handler = &dirty_writeback_centisecs_handler,
782 },
783 {
784 .ctl_name = VM_DIRTY_EXPIRE_CS,
785 .procname = "dirty_expire_centisecs",
786 .data = &dirty_expire_interval,
787 .maxlen = sizeof(dirty_expire_interval),
788 .mode = 0644,
789 .proc_handler = &proc_dointvec_userhz_jiffies,
790 },
791 {
792 .ctl_name = VM_NR_PDFLUSH_THREADS,
793 .procname = "nr_pdflush_threads",
794 .data = &nr_pdflush_threads,
795 .maxlen = sizeof nr_pdflush_threads,
796 .mode = 0444 /* read-only*/,
797 .proc_handler = &proc_dointvec,
798 },
799 {
800 .ctl_name = VM_SWAPPINESS,
801 .procname = "swappiness",
802 .data = &vm_swappiness,
803 .maxlen = sizeof(vm_swappiness),
804 .mode = 0644,
805 .proc_handler = &proc_dointvec_minmax,
806 .strategy = &sysctl_intvec,
807 .extra1 = &zero,
808 .extra2 = &one_hundred,
809 },
810 #ifdef CONFIG_HUGETLB_PAGE
811 {
812 .ctl_name = VM_HUGETLB_PAGES,
813 .procname = "nr_hugepages",
814 .data = &max_huge_pages,
815 .maxlen = sizeof(unsigned long),
816 .mode = 0644,
817 .proc_handler = &hugetlb_sysctl_handler,
818 .extra1 = (void *)&hugetlb_zero,
819 .extra2 = (void *)&hugetlb_infinity,
820 },
821 {
822 .ctl_name = VM_HUGETLB_GROUP,
823 .procname = "hugetlb_shm_group",
824 .data = &sysctl_hugetlb_shm_group,
825 .maxlen = sizeof(gid_t),
826 .mode = 0644,
827 .proc_handler = &proc_dointvec,
828 },
829 #endif
830 {
831 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
832 .procname = "lowmem_reserve_ratio",
833 .data = &sysctl_lowmem_reserve_ratio,
834 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
835 .mode = 0644,
836 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
837 .strategy = &sysctl_intvec,
838 },
839 {
840 .ctl_name = VM_DROP_PAGECACHE,
841 .procname = "drop_caches",
842 .data = &sysctl_drop_caches,
843 .maxlen = sizeof(int),
844 .mode = 0644,
845 .proc_handler = drop_caches_sysctl_handler,
846 .strategy = &sysctl_intvec,
847 },
848 {
849 .ctl_name = VM_MIN_FREE_KBYTES,
850 .procname = "min_free_kbytes",
851 .data = &min_free_kbytes,
852 .maxlen = sizeof(min_free_kbytes),
853 .mode = 0644,
854 .proc_handler = &min_free_kbytes_sysctl_handler,
855 .strategy = &sysctl_intvec,
856 .extra1 = &zero,
857 },
858 {
859 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
860 .procname = "percpu_pagelist_fraction",
861 .data = &percpu_pagelist_fraction,
862 .maxlen = sizeof(percpu_pagelist_fraction),
863 .mode = 0644,
864 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
865 .strategy = &sysctl_intvec,
866 .extra1 = &min_percpu_pagelist_fract,
867 },
868 #ifdef CONFIG_MMU
869 {
870 .ctl_name = VM_MAX_MAP_COUNT,
871 .procname = "max_map_count",
872 .data = &sysctl_max_map_count,
873 .maxlen = sizeof(sysctl_max_map_count),
874 .mode = 0644,
875 .proc_handler = &proc_dointvec
876 },
877 #endif
878 {
879 .ctl_name = VM_LAPTOP_MODE,
880 .procname = "laptop_mode",
881 .data = &laptop_mode,
882 .maxlen = sizeof(laptop_mode),
883 .mode = 0644,
884 .proc_handler = &proc_dointvec_jiffies,
885 .strategy = &sysctl_jiffies,
886 },
887 {
888 .ctl_name = VM_BLOCK_DUMP,
889 .procname = "block_dump",
890 .data = &block_dump,
891 .maxlen = sizeof(block_dump),
892 .mode = 0644,
893 .proc_handler = &proc_dointvec,
894 .strategy = &sysctl_intvec,
895 .extra1 = &zero,
896 },
897 {
898 .ctl_name = VM_VFS_CACHE_PRESSURE,
899 .procname = "vfs_cache_pressure",
900 .data = &sysctl_vfs_cache_pressure,
901 .maxlen = sizeof(sysctl_vfs_cache_pressure),
902 .mode = 0644,
903 .proc_handler = &proc_dointvec,
904 .strategy = &sysctl_intvec,
905 .extra1 = &zero,
906 },
907 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
908 {
909 .ctl_name = VM_LEGACY_VA_LAYOUT,
910 .procname = "legacy_va_layout",
911 .data = &sysctl_legacy_va_layout,
912 .maxlen = sizeof(sysctl_legacy_va_layout),
913 .mode = 0644,
914 .proc_handler = &proc_dointvec,
915 .strategy = &sysctl_intvec,
916 .extra1 = &zero,
917 },
918 #endif
919 #ifdef CONFIG_NUMA
920 {
921 .ctl_name = VM_ZONE_RECLAIM_MODE,
922 .procname = "zone_reclaim_mode",
923 .data = &zone_reclaim_mode,
924 .maxlen = sizeof(zone_reclaim_mode),
925 .mode = 0644,
926 .proc_handler = &proc_dointvec,
927 .strategy = &sysctl_intvec,
928 .extra1 = &zero,
929 },
930 {
931 .ctl_name = VM_MIN_UNMAPPED,
932 .procname = "min_unmapped_ratio",
933 .data = &sysctl_min_unmapped_ratio,
934 .maxlen = sizeof(sysctl_min_unmapped_ratio),
935 .mode = 0644,
936 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
937 .strategy = &sysctl_intvec,
938 .extra1 = &zero,
939 .extra2 = &one_hundred,
940 },
941 {
942 .ctl_name = VM_MIN_SLAB,
943 .procname = "min_slab_ratio",
944 .data = &sysctl_min_slab_ratio,
945 .maxlen = sizeof(sysctl_min_slab_ratio),
946 .mode = 0644,
947 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler,
948 .strategy = &sysctl_intvec,
949 .extra1 = &zero,
950 .extra2 = &one_hundred,
951 },
952 #endif
953 #ifdef CONFIG_SMP
954 {
955 .ctl_name = CTL_UNNUMBERED,
956 .procname = "stat_interval",
957 .data = &sysctl_stat_interval,
958 .maxlen = sizeof(sysctl_stat_interval),
959 .mode = 0644,
960 .proc_handler = &proc_dointvec_jiffies,
961 .strategy = &sysctl_jiffies,
962 },
963 #endif
964 #ifdef CONFIG_SECURITY
965 {
966 .ctl_name = CTL_UNNUMBERED,
967 .procname = "mmap_min_addr",
968 .data = &mmap_min_addr,
969 .maxlen = sizeof(unsigned long),
970 .mode = 0644,
971 .proc_handler = &proc_doulongvec_minmax,
972 },
973 #ifdef CONFIG_NUMA
974 {
975 .ctl_name = CTL_UNNUMBERED,
976 .procname = "numa_zonelist_order",
977 .data = &numa_zonelist_order,
978 .maxlen = NUMA_ZONELIST_ORDER_LEN,
979 .mode = 0644,
980 .proc_handler = &numa_zonelist_order_handler,
981 .strategy = &sysctl_string,
982 },
983 #endif
984 #endif
985 #if defined(CONFIG_X86_32) || \
986 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
987 {
988 .ctl_name = VM_VDSO_ENABLED,
989 .procname = "vdso_enabled",
990 .data = &vdso_enabled,
991 .maxlen = sizeof(vdso_enabled),
992 .mode = 0644,
993 .proc_handler = &proc_dointvec,
994 .strategy = &sysctl_intvec,
995 .extra1 = &zero,
996 },
997 #endif
998 /*
999 * NOTE: do not add new entries to this table unless you have read
1000 * Documentation/sysctl/ctl_unnumbered.txt
1001 */
1002 { .ctl_name = 0 }
1003 };
1004
1005 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1006 static ctl_table binfmt_misc_table[] = {
1007 { .ctl_name = 0 }
1008 };
1009 #endif
1010
1011 static ctl_table fs_table[] = {
1012 {
1013 .ctl_name = FS_NRINODE,
1014 .procname = "inode-nr",
1015 .data = &inodes_stat,
1016 .maxlen = 2*sizeof(int),
1017 .mode = 0444,
1018 .proc_handler = &proc_dointvec,
1019 },
1020 {
1021 .ctl_name = FS_STATINODE,
1022 .procname = "inode-state",
1023 .data = &inodes_stat,
1024 .maxlen = 7*sizeof(int),
1025 .mode = 0444,
1026 .proc_handler = &proc_dointvec,
1027 },
1028 {
1029 .ctl_name = FS_NRFILE,
1030 .procname = "file-nr",
1031 .data = &files_stat,
1032 .maxlen = 3*sizeof(int),
1033 .mode = 0444,
1034 .proc_handler = &proc_nr_files,
1035 },
1036 {
1037 .ctl_name = FS_MAXFILE,
1038 .procname = "file-max",
1039 .data = &files_stat.max_files,
1040 .maxlen = sizeof(int),
1041 .mode = 0644,
1042 .proc_handler = &proc_dointvec,
1043 },
1044 {
1045 .ctl_name = FS_DENTRY,
1046 .procname = "dentry-state",
1047 .data = &dentry_stat,
1048 .maxlen = 6*sizeof(int),
1049 .mode = 0444,
1050 .proc_handler = &proc_dointvec,
1051 },
1052 {
1053 .ctl_name = FS_OVERFLOWUID,
1054 .procname = "overflowuid",
1055 .data = &fs_overflowuid,
1056 .maxlen = sizeof(int),
1057 .mode = 0644,
1058 .proc_handler = &proc_dointvec_minmax,
1059 .strategy = &sysctl_intvec,
1060 .extra1 = &minolduid,
1061 .extra2 = &maxolduid,
1062 },
1063 {
1064 .ctl_name = FS_OVERFLOWGID,
1065 .procname = "overflowgid",
1066 .data = &fs_overflowgid,
1067 .maxlen = sizeof(int),
1068 .mode = 0644,
1069 .proc_handler = &proc_dointvec_minmax,
1070 .strategy = &sysctl_intvec,
1071 .extra1 = &minolduid,
1072 .extra2 = &maxolduid,
1073 },
1074 {
1075 .ctl_name = FS_LEASES,
1076 .procname = "leases-enable",
1077 .data = &leases_enable,
1078 .maxlen = sizeof(int),
1079 .mode = 0644,
1080 .proc_handler = &proc_dointvec,
1081 },
1082 #ifdef CONFIG_DNOTIFY
1083 {
1084 .ctl_name = FS_DIR_NOTIFY,
1085 .procname = "dir-notify-enable",
1086 .data = &dir_notify_enable,
1087 .maxlen = sizeof(int),
1088 .mode = 0644,
1089 .proc_handler = &proc_dointvec,
1090 },
1091 #endif
1092 #ifdef CONFIG_MMU
1093 {
1094 .ctl_name = FS_LEASE_TIME,
1095 .procname = "lease-break-time",
1096 .data = &lease_break_time,
1097 .maxlen = sizeof(int),
1098 .mode = 0644,
1099 .proc_handler = &proc_dointvec,
1100 },
1101 {
1102 .ctl_name = FS_AIO_NR,
1103 .procname = "aio-nr",
1104 .data = &aio_nr,
1105 .maxlen = sizeof(aio_nr),
1106 .mode = 0444,
1107 .proc_handler = &proc_doulongvec_minmax,
1108 },
1109 {
1110 .ctl_name = FS_AIO_MAX_NR,
1111 .procname = "aio-max-nr",
1112 .data = &aio_max_nr,
1113 .maxlen = sizeof(aio_max_nr),
1114 .mode = 0644,
1115 .proc_handler = &proc_doulongvec_minmax,
1116 },
1117 #ifdef CONFIG_INOTIFY_USER
1118 {
1119 .ctl_name = FS_INOTIFY,
1120 .procname = "inotify",
1121 .mode = 0555,
1122 .child = inotify_table,
1123 },
1124 #endif
1125 #endif
1126 {
1127 .ctl_name = KERN_SETUID_DUMPABLE,
1128 .procname = "suid_dumpable",
1129 .data = &suid_dumpable,
1130 .maxlen = sizeof(int),
1131 .mode = 0644,
1132 .proc_handler = &proc_dointvec,
1133 },
1134 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1135 {
1136 .ctl_name = CTL_UNNUMBERED,
1137 .procname = "binfmt_misc",
1138 .mode = 0555,
1139 .child = binfmt_misc_table,
1140 },
1141 #endif
1142 /*
1143 * NOTE: do not add new entries to this table unless you have read
1144 * Documentation/sysctl/ctl_unnumbered.txt
1145 */
1146 { .ctl_name = 0 }
1147 };
1148
1149 static ctl_table debug_table[] = {
1150 { .ctl_name = 0 }
1151 };
1152
1153 static ctl_table dev_table[] = {
1154 { .ctl_name = 0 }
1155 };
1156
1157 static DEFINE_SPINLOCK(sysctl_lock);
1158
1159 /* called under sysctl_lock */
1160 static int use_table(struct ctl_table_header *p)
1161 {
1162 if (unlikely(p->unregistering))
1163 return 0;
1164 p->used++;
1165 return 1;
1166 }
1167
1168 /* called under sysctl_lock */
1169 static void unuse_table(struct ctl_table_header *p)
1170 {
1171 if (!--p->used)
1172 if (unlikely(p->unregistering))
1173 complete(p->unregistering);
1174 }
1175
1176 /* called under sysctl_lock, will reacquire if has to wait */
1177 static void start_unregistering(struct ctl_table_header *p)
1178 {
1179 /*
1180 * if p->used is 0, nobody will ever touch that entry again;
1181 * we'll eliminate all paths to it before dropping sysctl_lock
1182 */
1183 if (unlikely(p->used)) {
1184 struct completion wait;
1185 init_completion(&wait);
1186 p->unregistering = &wait;
1187 spin_unlock(&sysctl_lock);
1188 wait_for_completion(&wait);
1189 spin_lock(&sysctl_lock);
1190 }
1191 /*
1192 * do not remove from the list until nobody holds it; walking the
1193 * list in do_sysctl() relies on that.
1194 */
1195 list_del_init(&p->ctl_entry);
1196 }
1197
1198 void sysctl_head_finish(struct ctl_table_header *head)
1199 {
1200 if (!head)
1201 return;
1202 spin_lock(&sysctl_lock);
1203 unuse_table(head);
1204 spin_unlock(&sysctl_lock);
1205 }
1206
1207 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1208 {
1209 struct ctl_table_header *head;
1210 struct list_head *tmp;
1211 spin_lock(&sysctl_lock);
1212 if (prev) {
1213 tmp = &prev->ctl_entry;
1214 unuse_table(prev);
1215 goto next;
1216 }
1217 tmp = &root_table_header.ctl_entry;
1218 for (;;) {
1219 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1220
1221 if (!use_table(head))
1222 goto next;
1223 spin_unlock(&sysctl_lock);
1224 return head;
1225 next:
1226 tmp = tmp->next;
1227 if (tmp == &root_table_header.ctl_entry)
1228 break;
1229 }
1230 spin_unlock(&sysctl_lock);
1231 return NULL;
1232 }
1233
1234 #ifdef CONFIG_SYSCTL_SYSCALL
1235 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1236 void __user *newval, size_t newlen)
1237 {
1238 struct ctl_table_header *head;
1239 int error = -ENOTDIR;
1240
1241 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1242 return -ENOTDIR;
1243 if (oldval) {
1244 int old_len;
1245 if (!oldlenp || get_user(old_len, oldlenp))
1246 return -EFAULT;
1247 }
1248
1249 for (head = sysctl_head_next(NULL); head;
1250 head = sysctl_head_next(head)) {
1251 error = parse_table(name, nlen, oldval, oldlenp,
1252 newval, newlen, head->ctl_table);
1253 if (error != -ENOTDIR) {
1254 sysctl_head_finish(head);
1255 break;
1256 }
1257 }
1258 return error;
1259 }
1260
1261 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1262 {
1263 struct __sysctl_args tmp;
1264 int error;
1265
1266 if (copy_from_user(&tmp, args, sizeof(tmp)))
1267 return -EFAULT;
1268
1269 lock_kernel();
1270 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1271 tmp.newval, tmp.newlen);
1272 unlock_kernel();
1273 return error;
1274 }
1275 #endif /* CONFIG_SYSCTL_SYSCALL */
1276
1277 /*
1278 * sysctl_perm does NOT grant the superuser all rights automatically, because
1279 * some sysctl variables are readonly even to root.
1280 */
1281
1282 static int test_perm(int mode, int op)
1283 {
1284 if (!current->euid)
1285 mode >>= 6;
1286 else if (in_egroup_p(0))
1287 mode >>= 3;
1288 if ((mode & op & 0007) == op)
1289 return 0;
1290 return -EACCES;
1291 }
1292
1293 int sysctl_perm(ctl_table *table, int op)
1294 {
1295 int error;
1296 error = security_sysctl(table, op);
1297 if (error)
1298 return error;
1299 return test_perm(table->mode, op);
1300 }
1301
1302 #ifdef CONFIG_SYSCTL_SYSCALL
1303 static int parse_table(int __user *name, int nlen,
1304 void __user *oldval, size_t __user *oldlenp,
1305 void __user *newval, size_t newlen,
1306 ctl_table *table)
1307 {
1308 int n;
1309 repeat:
1310 if (!nlen)
1311 return -ENOTDIR;
1312 if (get_user(n, name))
1313 return -EFAULT;
1314 for ( ; table->ctl_name || table->procname; table++) {
1315 if (!table->ctl_name)
1316 continue;
1317 if (n == table->ctl_name) {
1318 int error;
1319 if (table->child) {
1320 if (sysctl_perm(table, 001))
1321 return -EPERM;
1322 name++;
1323 nlen--;
1324 table = table->child;
1325 goto repeat;
1326 }
1327 error = do_sysctl_strategy(table, name, nlen,
1328 oldval, oldlenp,
1329 newval, newlen);
1330 return error;
1331 }
1332 }
1333 return -ENOTDIR;
1334 }
1335
1336 /* Perform the actual read/write of a sysctl table entry. */
1337 int do_sysctl_strategy (ctl_table *table,
1338 int __user *name, int nlen,
1339 void __user *oldval, size_t __user *oldlenp,
1340 void __user *newval, size_t newlen)
1341 {
1342 int op = 0, rc;
1343 size_t len;
1344
1345 if (oldval)
1346 op |= 004;
1347 if (newval)
1348 op |= 002;
1349 if (sysctl_perm(table, op))
1350 return -EPERM;
1351
1352 if (table->strategy) {
1353 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1354 newval, newlen);
1355 if (rc < 0)
1356 return rc;
1357 if (rc > 0)
1358 return 0;
1359 }
1360
1361 /* If there is no strategy routine, or if the strategy returns
1362 * zero, proceed with automatic r/w */
1363 if (table->data && table->maxlen) {
1364 if (oldval && oldlenp) {
1365 if (get_user(len, oldlenp))
1366 return -EFAULT;
1367 if (len) {
1368 if (len > table->maxlen)
1369 len = table->maxlen;
1370 if(copy_to_user(oldval, table->data, len))
1371 return -EFAULT;
1372 if(put_user(len, oldlenp))
1373 return -EFAULT;
1374 }
1375 }
1376 if (newval && newlen) {
1377 len = newlen;
1378 if (len > table->maxlen)
1379 len = table->maxlen;
1380 if(copy_from_user(table->data, newval, len))
1381 return -EFAULT;
1382 }
1383 }
1384 return 0;
1385 }
1386 #endif /* CONFIG_SYSCTL_SYSCALL */
1387
1388 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1389 {
1390 for (; table->ctl_name || table->procname; table++) {
1391 table->parent = parent;
1392 if (table->child)
1393 sysctl_set_parent(table, table->child);
1394 }
1395 }
1396
1397 static __init int sysctl_init(void)
1398 {
1399 sysctl_set_parent(NULL, root_table);
1400 return 0;
1401 }
1402
1403 core_initcall(sysctl_init);
1404
1405 /**
1406 * register_sysctl_table - register a sysctl hierarchy
1407 * @table: the top-level table structure
1408 *
1409 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1410 * array. An entry with a ctl_name of 0 terminates the table.
1411 *
1412 * The members of the &ctl_table structure are used as follows:
1413 *
1414 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1415 * must be unique within that level of sysctl
1416 *
1417 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1418 * enter a sysctl file
1419 *
1420 * data - a pointer to data for use by proc_handler
1421 *
1422 * maxlen - the maximum size in bytes of the data
1423 *
1424 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1425 *
1426 * child - a pointer to the child sysctl table if this entry is a directory, or
1427 * %NULL.
1428 *
1429 * proc_handler - the text handler routine (described below)
1430 *
1431 * strategy - the strategy routine (described below)
1432 *
1433 * de - for internal use by the sysctl routines
1434 *
1435 * extra1, extra2 - extra pointers usable by the proc handler routines
1436 *
1437 * Leaf nodes in the sysctl tree will be represented by a single file
1438 * under /proc; non-leaf nodes will be represented by directories.
1439 *
1440 * sysctl(2) can automatically manage read and write requests through
1441 * the sysctl table. The data and maxlen fields of the ctl_table
1442 * struct enable minimal validation of the values being written to be
1443 * performed, and the mode field allows minimal authentication.
1444 *
1445 * More sophisticated management can be enabled by the provision of a
1446 * strategy routine with the table entry. This will be called before
1447 * any automatic read or write of the data is performed.
1448 *
1449 * The strategy routine may return
1450 *
1451 * < 0 - Error occurred (error is passed to user process)
1452 *
1453 * 0 - OK - proceed with automatic read or write.
1454 *
1455 * > 0 - OK - read or write has been done by the strategy routine, so
1456 * return immediately.
1457 *
1458 * There must be a proc_handler routine for any terminal nodes
1459 * mirrored under /proc/sys (non-terminals are handled by a built-in
1460 * directory handler). Several default handlers are available to
1461 * cover common cases -
1462 *
1463 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1464 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1465 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1466 *
1467 * It is the handler's job to read the input buffer from user memory
1468 * and process it. The handler should return 0 on success.
1469 *
1470 * This routine returns %NULL on a failure to register, and a pointer
1471 * to the table header on success.
1472 */
1473 struct ctl_table_header *register_sysctl_table(ctl_table * table)
1474 {
1475 struct ctl_table_header *tmp;
1476 tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1477 if (!tmp)
1478 return NULL;
1479 tmp->ctl_table = table;
1480 INIT_LIST_HEAD(&tmp->ctl_entry);
1481 tmp->used = 0;
1482 tmp->unregistering = NULL;
1483 sysctl_set_parent(NULL, table);
1484 spin_lock(&sysctl_lock);
1485 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1486 spin_unlock(&sysctl_lock);
1487 return tmp;
1488 }
1489
1490 /**
1491 * unregister_sysctl_table - unregister a sysctl table hierarchy
1492 * @header: the header returned from register_sysctl_table
1493 *
1494 * Unregisters the sysctl table and all children. proc entries may not
1495 * actually be removed until they are no longer used by anyone.
1496 */
1497 void unregister_sysctl_table(struct ctl_table_header * header)
1498 {
1499 might_sleep();
1500 spin_lock(&sysctl_lock);
1501 start_unregistering(header);
1502 spin_unlock(&sysctl_lock);
1503 kfree(header);
1504 }
1505
1506 #else /* !CONFIG_SYSCTL */
1507 struct ctl_table_header *register_sysctl_table(ctl_table * table)
1508 {
1509 return NULL;
1510 }
1511
1512 void unregister_sysctl_table(struct ctl_table_header * table)
1513 {
1514 }
1515
1516 #endif /* CONFIG_SYSCTL */
1517
1518 /*
1519 * /proc/sys support
1520 */
1521
1522 #ifdef CONFIG_PROC_SYSCTL
1523
1524 static int _proc_do_string(void* data, int maxlen, int write,
1525 struct file *filp, void __user *buffer,
1526 size_t *lenp, loff_t *ppos)
1527 {
1528 size_t len;
1529 char __user *p;
1530 char c;
1531
1532 if (!data || !maxlen || !*lenp) {
1533 *lenp = 0;
1534 return 0;
1535 }
1536
1537 if (write) {
1538 len = 0;
1539 p = buffer;
1540 while (len < *lenp) {
1541 if (get_user(c, p++))
1542 return -EFAULT;
1543 if (c == 0 || c == '\n')
1544 break;
1545 len++;
1546 }
1547 if (len >= maxlen)
1548 len = maxlen-1;
1549 if(copy_from_user(data, buffer, len))
1550 return -EFAULT;
1551 ((char *) data)[len] = 0;
1552 *ppos += *lenp;
1553 } else {
1554 len = strlen(data);
1555 if (len > maxlen)
1556 len = maxlen;
1557
1558 if (*ppos > len) {
1559 *lenp = 0;
1560 return 0;
1561 }
1562
1563 data += *ppos;
1564 len -= *ppos;
1565
1566 if (len > *lenp)
1567 len = *lenp;
1568 if (len)
1569 if(copy_to_user(buffer, data, len))
1570 return -EFAULT;
1571 if (len < *lenp) {
1572 if(put_user('\n', ((char __user *) buffer) + len))
1573 return -EFAULT;
1574 len++;
1575 }
1576 *lenp = len;
1577 *ppos += len;
1578 }
1579 return 0;
1580 }
1581
1582 /**
1583 * proc_dostring - read a string sysctl
1584 * @table: the sysctl table
1585 * @write: %TRUE if this is a write to the sysctl file
1586 * @filp: the file structure
1587 * @buffer: the user buffer
1588 * @lenp: the size of the user buffer
1589 * @ppos: file position
1590 *
1591 * Reads/writes a string from/to the user buffer. If the kernel
1592 * buffer provided is not large enough to hold the string, the
1593 * string is truncated. The copied string is %NULL-terminated.
1594 * If the string is being read by the user process, it is copied
1595 * and a newline '\n' is added. It is truncated if the buffer is
1596 * not large enough.
1597 *
1598 * Returns 0 on success.
1599 */
1600 int proc_dostring(ctl_table *table, int write, struct file *filp,
1601 void __user *buffer, size_t *lenp, loff_t *ppos)
1602 {
1603 return _proc_do_string(table->data, table->maxlen, write, filp,
1604 buffer, lenp, ppos);
1605 }
1606
1607
1608 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1609 int *valp,
1610 int write, void *data)
1611 {
1612 if (write) {
1613 *valp = *negp ? -*lvalp : *lvalp;
1614 } else {
1615 int val = *valp;
1616 if (val < 0) {
1617 *negp = -1;
1618 *lvalp = (unsigned long)-val;
1619 } else {
1620 *negp = 0;
1621 *lvalp = (unsigned long)val;
1622 }
1623 }
1624 return 0;
1625 }
1626
1627 static int __do_proc_dointvec(void *tbl_data, ctl_table *table,
1628 int write, struct file *filp, void __user *buffer,
1629 size_t *lenp, loff_t *ppos,
1630 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1631 int write, void *data),
1632 void *data)
1633 {
1634 #define TMPBUFLEN 21
1635 int *i, vleft, first=1, neg, val;
1636 unsigned long lval;
1637 size_t left, len;
1638
1639 char buf[TMPBUFLEN], *p;
1640 char __user *s = buffer;
1641
1642 if (!tbl_data || !table->maxlen || !*lenp ||
1643 (*ppos && !write)) {
1644 *lenp = 0;
1645 return 0;
1646 }
1647
1648 i = (int *) tbl_data;
1649 vleft = table->maxlen / sizeof(*i);
1650 left = *lenp;
1651
1652 if (!conv)
1653 conv = do_proc_dointvec_conv;
1654
1655 for (; left && vleft--; i++, first=0) {
1656 if (write) {
1657 while (left) {
1658 char c;
1659 if (get_user(c, s))
1660 return -EFAULT;
1661 if (!isspace(c))
1662 break;
1663 left--;
1664 s++;
1665 }
1666 if (!left)
1667 break;
1668 neg = 0;
1669 len = left;
1670 if (len > sizeof(buf) - 1)
1671 len = sizeof(buf) - 1;
1672 if (copy_from_user(buf, s, len))
1673 return -EFAULT;
1674 buf[len] = 0;
1675 p = buf;
1676 if (*p == '-' && left > 1) {
1677 neg = 1;
1678 p++;
1679 }
1680 if (*p < '0' || *p > '9')
1681 break;
1682
1683 lval = simple_strtoul(p, &p, 0);
1684
1685 len = p-buf;
1686 if ((len < left) && *p && !isspace(*p))
1687 break;
1688 if (neg)
1689 val = -val;
1690 s += len;
1691 left -= len;
1692
1693 if (conv(&neg, &lval, i, 1, data))
1694 break;
1695 } else {
1696 p = buf;
1697 if (!first)
1698 *p++ = '\t';
1699
1700 if (conv(&neg, &lval, i, 0, data))
1701 break;
1702
1703 sprintf(p, "%s%lu", neg ? "-" : "", lval);
1704 len = strlen(buf);
1705 if (len > left)
1706 len = left;
1707 if(copy_to_user(s, buf, len))
1708 return -EFAULT;
1709 left -= len;
1710 s += len;
1711 }
1712 }
1713
1714 if (!write && !first && left) {
1715 if(put_user('\n', s))
1716 return -EFAULT;
1717 left--, s++;
1718 }
1719 if (write) {
1720 while (left) {
1721 char c;
1722 if (get_user(c, s++))
1723 return -EFAULT;
1724 if (!isspace(c))
1725 break;
1726 left--;
1727 }
1728 }
1729 if (write && first)
1730 return -EINVAL;
1731 *lenp -= left;
1732 *ppos += *lenp;
1733 return 0;
1734 #undef TMPBUFLEN
1735 }
1736
1737 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1738 void __user *buffer, size_t *lenp, loff_t *ppos,
1739 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1740 int write, void *data),
1741 void *data)
1742 {
1743 return __do_proc_dointvec(table->data, table, write, filp,
1744 buffer, lenp, ppos, conv, data);
1745 }
1746
1747 /**
1748 * proc_dointvec - read a vector of integers
1749 * @table: the sysctl table
1750 * @write: %TRUE if this is a write to the sysctl file
1751 * @filp: the file structure
1752 * @buffer: the user buffer
1753 * @lenp: the size of the user buffer
1754 * @ppos: file position
1755 *
1756 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1757 * values from/to the user buffer, treated as an ASCII string.
1758 *
1759 * Returns 0 on success.
1760 */
1761 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1762 void __user *buffer, size_t *lenp, loff_t *ppos)
1763 {
1764 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1765 NULL,NULL);
1766 }
1767
1768 #define OP_SET 0
1769 #define OP_AND 1
1770 #define OP_OR 2
1771
1772 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1773 int *valp,
1774 int write, void *data)
1775 {
1776 int op = *(int *)data;
1777 if (write) {
1778 int val = *negp ? -*lvalp : *lvalp;
1779 switch(op) {
1780 case OP_SET: *valp = val; break;
1781 case OP_AND: *valp &= val; break;
1782 case OP_OR: *valp |= val; break;
1783 }
1784 } else {
1785 int val = *valp;
1786 if (val < 0) {
1787 *negp = -1;
1788 *lvalp = (unsigned long)-val;
1789 } else {
1790 *negp = 0;
1791 *lvalp = (unsigned long)val;
1792 }
1793 }
1794 return 0;
1795 }
1796
1797 /*
1798 * init may raise the set.
1799 */
1800
1801 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1802 void __user *buffer, size_t *lenp, loff_t *ppos)
1803 {
1804 int op;
1805
1806 if (write && !capable(CAP_SYS_MODULE)) {
1807 return -EPERM;
1808 }
1809
1810 op = is_init(current) ? OP_SET : OP_AND;
1811 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1812 do_proc_dointvec_bset_conv,&op);
1813 }
1814
1815 /*
1816 * Taint values can only be increased
1817 */
1818 static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
1819 void __user *buffer, size_t *lenp, loff_t *ppos)
1820 {
1821 int op;
1822
1823 if (write && !capable(CAP_SYS_ADMIN))
1824 return -EPERM;
1825
1826 op = OP_OR;
1827 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1828 do_proc_dointvec_bset_conv,&op);
1829 }
1830
1831 struct do_proc_dointvec_minmax_conv_param {
1832 int *min;
1833 int *max;
1834 };
1835
1836 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1837 int *valp,
1838 int write, void *data)
1839 {
1840 struct do_proc_dointvec_minmax_conv_param *param = data;
1841 if (write) {
1842 int val = *negp ? -*lvalp : *lvalp;
1843 if ((param->min && *param->min > val) ||
1844 (param->max && *param->max < val))
1845 return -EINVAL;
1846 *valp = val;
1847 } else {
1848 int val = *valp;
1849 if (val < 0) {
1850 *negp = -1;
1851 *lvalp = (unsigned long)-val;
1852 } else {
1853 *negp = 0;
1854 *lvalp = (unsigned long)val;
1855 }
1856 }
1857 return 0;
1858 }
1859
1860 /**
1861 * proc_dointvec_minmax - read a vector of integers with min/max values
1862 * @table: the sysctl table
1863 * @write: %TRUE if this is a write to the sysctl file
1864 * @filp: the file structure
1865 * @buffer: the user buffer
1866 * @lenp: the size of the user buffer
1867 * @ppos: file position
1868 *
1869 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1870 * values from/to the user buffer, treated as an ASCII string.
1871 *
1872 * This routine will ensure the values are within the range specified by
1873 * table->extra1 (min) and table->extra2 (max).
1874 *
1875 * Returns 0 on success.
1876 */
1877 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1878 void __user *buffer, size_t *lenp, loff_t *ppos)
1879 {
1880 struct do_proc_dointvec_minmax_conv_param param = {
1881 .min = (int *) table->extra1,
1882 .max = (int *) table->extra2,
1883 };
1884 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1885 do_proc_dointvec_minmax_conv, &param);
1886 }
1887
1888 static int __do_proc_doulongvec_minmax(void *data, ctl_table *table, int write,
1889 struct file *filp,
1890 void __user *buffer,
1891 size_t *lenp, loff_t *ppos,
1892 unsigned long convmul,
1893 unsigned long convdiv)
1894 {
1895 #define TMPBUFLEN 21
1896 unsigned long *i, *min, *max, val;
1897 int vleft, first=1, neg;
1898 size_t len, left;
1899 char buf[TMPBUFLEN], *p;
1900 char __user *s = buffer;
1901
1902 if (!data || !table->maxlen || !*lenp ||
1903 (*ppos && !write)) {
1904 *lenp = 0;
1905 return 0;
1906 }
1907
1908 i = (unsigned long *) data;
1909 min = (unsigned long *) table->extra1;
1910 max = (unsigned long *) table->extra2;
1911 vleft = table->maxlen / sizeof(unsigned long);
1912 left = *lenp;
1913
1914 for (; left && vleft--; i++, min++, max++, first=0) {
1915 if (write) {
1916 while (left) {
1917 char c;
1918 if (get_user(c, s))
1919 return -EFAULT;
1920 if (!isspace(c))
1921 break;
1922 left--;
1923 s++;
1924 }
1925 if (!left)
1926 break;
1927 neg = 0;
1928 len = left;
1929 if (len > TMPBUFLEN-1)
1930 len = TMPBUFLEN-1;
1931 if (copy_from_user(buf, s, len))
1932 return -EFAULT;
1933 buf[len] = 0;
1934 p = buf;
1935 if (*p == '-' && left > 1) {
1936 neg = 1;
1937 p++;
1938 }
1939 if (*p < '0' || *p > '9')
1940 break;
1941 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1942 len = p-buf;
1943 if ((len < left) && *p && !isspace(*p))
1944 break;
1945 if (neg)
1946 val = -val;
1947 s += len;
1948 left -= len;
1949
1950 if(neg)
1951 continue;
1952 if ((min && val < *min) || (max && val > *max))
1953 continue;
1954 *i = val;
1955 } else {
1956 p = buf;
1957 if (!first)
1958 *p++ = '\t';
1959 sprintf(p, "%lu", convdiv * (*i) / convmul);
1960 len = strlen(buf);
1961 if (len > left)
1962 len = left;
1963 if(copy_to_user(s, buf, len))
1964 return -EFAULT;
1965 left -= len;
1966 s += len;
1967 }
1968 }
1969
1970 if (!write && !first && left) {
1971 if(put_user('\n', s))
1972 return -EFAULT;
1973 left--, s++;
1974 }
1975 if (write) {
1976 while (left) {
1977 char c;
1978 if (get_user(c, s++))
1979 return -EFAULT;
1980 if (!isspace(c))
1981 break;
1982 left--;
1983 }
1984 }
1985 if (write && first)
1986 return -EINVAL;
1987 *lenp -= left;
1988 *ppos += *lenp;
1989 return 0;
1990 #undef TMPBUFLEN
1991 }
1992
1993 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1994 struct file *filp,
1995 void __user *buffer,
1996 size_t *lenp, loff_t *ppos,
1997 unsigned long convmul,
1998 unsigned long convdiv)
1999 {
2000 return __do_proc_doulongvec_minmax(table->data, table, write,
2001 filp, buffer, lenp, ppos, convmul, convdiv);
2002 }
2003
2004 /**
2005 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2006 * @table: the sysctl table
2007 * @write: %TRUE if this is a write to the sysctl file
2008 * @filp: the file structure
2009 * @buffer: the user buffer
2010 * @lenp: the size of the user buffer
2011 * @ppos: file position
2012 *
2013 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2014 * values from/to the user buffer, treated as an ASCII string.
2015 *
2016 * This routine will ensure the values are within the range specified by
2017 * table->extra1 (min) and table->extra2 (max).
2018 *
2019 * Returns 0 on success.
2020 */
2021 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2022 void __user *buffer, size_t *lenp, loff_t *ppos)
2023 {
2024 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2025 }
2026
2027 /**
2028 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2029 * @table: the sysctl table
2030 * @write: %TRUE if this is a write to the sysctl file
2031 * @filp: the file structure
2032 * @buffer: the user buffer
2033 * @lenp: the size of the user buffer
2034 * @ppos: file position
2035 *
2036 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2037 * values from/to the user buffer, treated as an ASCII string. The values
2038 * are treated as milliseconds, and converted to jiffies when they are stored.
2039 *
2040 * This routine will ensure the values are within the range specified by
2041 * table->extra1 (min) and table->extra2 (max).
2042 *
2043 * Returns 0 on success.
2044 */
2045 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2046 struct file *filp,
2047 void __user *buffer,
2048 size_t *lenp, loff_t *ppos)
2049 {
2050 return do_proc_doulongvec_minmax(table, write, filp, buffer,
2051 lenp, ppos, HZ, 1000l);
2052 }
2053
2054
2055 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2056 int *valp,
2057 int write, void *data)
2058 {
2059 if (write) {
2060 if (*lvalp > LONG_MAX / HZ)
2061 return 1;
2062 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2063 } else {
2064 int val = *valp;
2065 unsigned long lval;
2066 if (val < 0) {
2067 *negp = -1;
2068 lval = (unsigned long)-val;
2069 } else {
2070 *negp = 0;
2071 lval = (unsigned long)val;
2072 }
2073 *lvalp = lval / HZ;
2074 }
2075 return 0;
2076 }
2077
2078 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2079 int *valp,
2080 int write, void *data)
2081 {
2082 if (write) {
2083 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2084 return 1;
2085 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2086 } else {
2087 int val = *valp;
2088 unsigned long lval;
2089 if (val < 0) {
2090 *negp = -1;
2091 lval = (unsigned long)-val;
2092 } else {
2093 *negp = 0;
2094 lval = (unsigned long)val;
2095 }
2096 *lvalp = jiffies_to_clock_t(lval);
2097 }
2098 return 0;
2099 }
2100
2101 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2102 int *valp,
2103 int write, void *data)
2104 {
2105 if (write) {
2106 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2107 } else {
2108 int val = *valp;
2109 unsigned long lval;
2110 if (val < 0) {
2111 *negp = -1;
2112 lval = (unsigned long)-val;
2113 } else {
2114 *negp = 0;
2115 lval = (unsigned long)val;
2116 }
2117 *lvalp = jiffies_to_msecs(lval);
2118 }
2119 return 0;
2120 }
2121
2122 /**
2123 * proc_dointvec_jiffies - read a vector of integers as seconds
2124 * @table: the sysctl table
2125 * @write: %TRUE if this is a write to the sysctl file
2126 * @filp: the file structure
2127 * @buffer: the user buffer
2128 * @lenp: the size of the user buffer
2129 * @ppos: file position
2130 *
2131 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2132 * values from/to the user buffer, treated as an ASCII string.
2133 * The values read are assumed to be in seconds, and are converted into
2134 * jiffies.
2135 *
2136 * Returns 0 on success.
2137 */
2138 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2139 void __user *buffer, size_t *lenp, loff_t *ppos)
2140 {
2141 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2142 do_proc_dointvec_jiffies_conv,NULL);
2143 }
2144
2145 /**
2146 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2147 * @table: the sysctl table
2148 * @write: %TRUE if this is a write to the sysctl file
2149 * @filp: the file structure
2150 * @buffer: the user buffer
2151 * @lenp: the size of the user buffer
2152 * @ppos: pointer to the file position
2153 *
2154 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2155 * values from/to the user buffer, treated as an ASCII string.
2156 * The values read are assumed to be in 1/USER_HZ seconds, and
2157 * are converted into jiffies.
2158 *
2159 * Returns 0 on success.
2160 */
2161 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2162 void __user *buffer, size_t *lenp, loff_t *ppos)
2163 {
2164 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2165 do_proc_dointvec_userhz_jiffies_conv,NULL);
2166 }
2167
2168 /**
2169 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2170 * @table: the sysctl table
2171 * @write: %TRUE if this is a write to the sysctl file
2172 * @filp: the file structure
2173 * @buffer: the user buffer
2174 * @lenp: the size of the user buffer
2175 * @ppos: file position
2176 * @ppos: the current position in the file
2177 *
2178 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2179 * values from/to the user buffer, treated as an ASCII string.
2180 * The values read are assumed to be in 1/1000 seconds, and
2181 * are converted into jiffies.
2182 *
2183 * Returns 0 on success.
2184 */
2185 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2186 void __user *buffer, size_t *lenp, loff_t *ppos)
2187 {
2188 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2189 do_proc_dointvec_ms_jiffies_conv, NULL);
2190 }
2191
2192 static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
2193 void __user *buffer, size_t *lenp, loff_t *ppos)
2194 {
2195 struct pid *new_pid;
2196 pid_t tmp;
2197 int r;
2198
2199 tmp = pid_nr(cad_pid);
2200
2201 r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2202 lenp, ppos, NULL, NULL);
2203 if (r || !write)
2204 return r;
2205
2206 new_pid = find_get_pid(tmp);
2207 if (!new_pid)
2208 return -ESRCH;
2209
2210 put_pid(xchg(&cad_pid, new_pid));
2211 return 0;
2212 }
2213
2214 #else /* CONFIG_PROC_FS */
2215
2216 int proc_dostring(ctl_table *table, int write, struct file *filp,
2217 void __user *buffer, size_t *lenp, loff_t *ppos)
2218 {
2219 return -ENOSYS;
2220 }
2221
2222 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2223 void __user *buffer, size_t *lenp, loff_t *ppos)
2224 {
2225 return -ENOSYS;
2226 }
2227
2228 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2229 void __user *buffer, size_t *lenp, loff_t *ppos)
2230 {
2231 return -ENOSYS;
2232 }
2233
2234 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2235 void __user *buffer, size_t *lenp, loff_t *ppos)
2236 {
2237 return -ENOSYS;
2238 }
2239
2240 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2241 void __user *buffer, size_t *lenp, loff_t *ppos)
2242 {
2243 return -ENOSYS;
2244 }
2245
2246 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2247 void __user *buffer, size_t *lenp, loff_t *ppos)
2248 {
2249 return -ENOSYS;
2250 }
2251
2252 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2253 void __user *buffer, size_t *lenp, loff_t *ppos)
2254 {
2255 return -ENOSYS;
2256 }
2257
2258 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2259 void __user *buffer, size_t *lenp, loff_t *ppos)
2260 {
2261 return -ENOSYS;
2262 }
2263
2264 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2265 struct file *filp,
2266 void __user *buffer,
2267 size_t *lenp, loff_t *ppos)
2268 {
2269 return -ENOSYS;
2270 }
2271
2272
2273 #endif /* CONFIG_PROC_FS */
2274
2275
2276 #ifdef CONFIG_SYSCTL_SYSCALL
2277 /*
2278 * General sysctl support routines
2279 */
2280
2281 /* The generic string strategy routine: */
2282 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2283 void __user *oldval, size_t __user *oldlenp,
2284 void __user *newval, size_t newlen)
2285 {
2286 if (!table->data || !table->maxlen)
2287 return -ENOTDIR;
2288
2289 if (oldval && oldlenp) {
2290 size_t bufsize;
2291 if (get_user(bufsize, oldlenp))
2292 return -EFAULT;
2293 if (bufsize) {
2294 size_t len = strlen(table->data), copied;
2295
2296 /* This shouldn't trigger for a well-formed sysctl */
2297 if (len > table->maxlen)
2298 len = table->maxlen;
2299
2300 /* Copy up to a max of bufsize-1 bytes of the string */
2301 copied = (len >= bufsize) ? bufsize - 1 : len;
2302
2303 if (copy_to_user(oldval, table->data, copied) ||
2304 put_user(0, (char __user *)(oldval + copied)))
2305 return -EFAULT;
2306 if (put_user(len, oldlenp))
2307 return -EFAULT;
2308 }
2309 }
2310 if (newval && newlen) {
2311 size_t len = newlen;
2312 if (len > table->maxlen)
2313 len = table->maxlen;
2314 if(copy_from_user(table->data, newval, len))
2315 return -EFAULT;
2316 if (len == table->maxlen)
2317 len--;
2318 ((char *) table->data)[len] = 0;
2319 }
2320 return 1;
2321 }
2322
2323 /*
2324 * This function makes sure that all of the integers in the vector
2325 * are between the minimum and maximum values given in the arrays
2326 * table->extra1 and table->extra2, respectively.
2327 */
2328 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2329 void __user *oldval, size_t __user *oldlenp,
2330 void __user *newval, size_t newlen)
2331 {
2332
2333 if (newval && newlen) {
2334 int __user *vec = (int __user *) newval;
2335 int *min = (int *) table->extra1;
2336 int *max = (int *) table->extra2;
2337 size_t length;
2338 int i;
2339
2340 if (newlen % sizeof(int) != 0)
2341 return -EINVAL;
2342
2343 if (!table->extra1 && !table->extra2)
2344 return 0;
2345
2346 if (newlen > table->maxlen)
2347 newlen = table->maxlen;
2348 length = newlen / sizeof(int);
2349
2350 for (i = 0; i < length; i++) {
2351 int value;
2352 if (get_user(value, vec + i))
2353 return -EFAULT;
2354 if (min && value < min[i])
2355 return -EINVAL;
2356 if (max && value > max[i])
2357 return -EINVAL;
2358 }
2359 }
2360 return 0;
2361 }
2362
2363 /* Strategy function to convert jiffies to seconds */
2364 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2365 void __user *oldval, size_t __user *oldlenp,
2366 void __user *newval, size_t newlen)
2367 {
2368 if (oldval && oldlenp) {
2369 size_t olen;
2370
2371 if (get_user(olen, oldlenp))
2372 return -EFAULT;
2373 if (olen) {
2374 int val;
2375
2376 if (olen < sizeof(int))
2377 return -EINVAL;
2378
2379 val = *(int *)(table->data) / HZ;
2380 if (put_user(val, (int __user *)oldval))
2381 return -EFAULT;
2382 if (put_user(sizeof(int), oldlenp))
2383 return -EFAULT;
2384 }
2385 }
2386 if (newval && newlen) {
2387 int new;
2388 if (newlen != sizeof(int))
2389 return -EINVAL;
2390 if (get_user(new, (int __user *)newval))
2391 return -EFAULT;
2392 *(int *)(table->data) = new*HZ;
2393 }
2394 return 1;
2395 }
2396
2397 /* Strategy function to convert jiffies to seconds */
2398 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2399 void __user *oldval, size_t __user *oldlenp,
2400 void __user *newval, size_t newlen)
2401 {
2402 if (oldval && oldlenp) {
2403 size_t olen;
2404
2405 if (get_user(olen, oldlenp))
2406 return -EFAULT;
2407 if (olen) {
2408 int val;
2409
2410 if (olen < sizeof(int))
2411 return -EINVAL;
2412
2413 val = jiffies_to_msecs(*(int *)(table->data));
2414 if (put_user(val, (int __user *)oldval))
2415 return -EFAULT;
2416 if (put_user(sizeof(int), oldlenp))
2417 return -EFAULT;
2418 }
2419 }
2420 if (newval && newlen) {
2421 int new;
2422 if (newlen != sizeof(int))
2423 return -EINVAL;
2424 if (get_user(new, (int __user *)newval))
2425 return -EFAULT;
2426 *(int *)(table->data) = msecs_to_jiffies(new);
2427 }
2428 return 1;
2429 }
2430
2431
2432
2433 #else /* CONFIG_SYSCTL_SYSCALL */
2434
2435
2436 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2437 {
2438 static int msg_count;
2439 struct __sysctl_args tmp;
2440 int name[CTL_MAXNAME];
2441 int i;
2442
2443 /* Read in the sysctl name for better debug message logging */
2444 if (copy_from_user(&tmp, args, sizeof(tmp)))
2445 return -EFAULT;
2446 if (tmp.nlen <= 0 || tmp.nlen >= CTL_MAXNAME)
2447 return -ENOTDIR;
2448 for (i = 0; i < tmp.nlen; i++)
2449 if (get_user(name[i], tmp.name + i))
2450 return -EFAULT;
2451
2452 /* Ignore accesses to kernel.version */
2453 if ((tmp.nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
2454 goto out;
2455
2456 if (msg_count < 5) {
2457 msg_count++;
2458 printk(KERN_INFO
2459 "warning: process `%s' used the removed sysctl "
2460 "system call with ", current->comm);
2461 for (i = 0; i < tmp.nlen; i++)
2462 printk("%d.", name[i]);
2463 printk("\n");
2464 }
2465 out:
2466 return -ENOSYS;
2467 }
2468
2469 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2470 void __user *oldval, size_t __user *oldlenp,
2471 void __user *newval, size_t newlen)
2472 {
2473 return -ENOSYS;
2474 }
2475
2476 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2477 void __user *oldval, size_t __user *oldlenp,
2478 void __user *newval, size_t newlen)
2479 {
2480 return -ENOSYS;
2481 }
2482
2483 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2484 void __user *oldval, size_t __user *oldlenp,
2485 void __user *newval, size_t newlen)
2486 {
2487 return -ENOSYS;
2488 }
2489
2490 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2491 void __user *oldval, size_t __user *oldlenp,
2492 void __user *newval, size_t newlen)
2493 {
2494 return -ENOSYS;
2495 }
2496
2497 #endif /* CONFIG_SYSCTL_SYSCALL */
2498
2499 /*
2500 * No sense putting this after each symbol definition, twice,
2501 * exception granted :-)
2502 */
2503 EXPORT_SYMBOL(proc_dointvec);
2504 EXPORT_SYMBOL(proc_dointvec_jiffies);
2505 EXPORT_SYMBOL(proc_dointvec_minmax);
2506 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2507 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2508 EXPORT_SYMBOL(proc_dostring);
2509 EXPORT_SYMBOL(proc_doulongvec_minmax);
2510 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2511 EXPORT_SYMBOL(register_sysctl_table);
2512 EXPORT_SYMBOL(sysctl_intvec);
2513 EXPORT_SYMBOL(sysctl_jiffies);
2514 EXPORT_SYMBOL(sysctl_ms_jiffies);
2515 EXPORT_SYMBOL(sysctl_string);
2516 EXPORT_SYMBOL(unregister_sysctl_table);
Support for the Chinese Samsung S3C2440 based development boards