[PATCH] ZVC/zone_reclaim: Leave 1% of unmapped pagecache pages for file I/O
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / kernel / sysctl.c
CommitLineData
1da177e4
LT
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
1da177e4
LT
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>
c59ede7b 27#include <linux/capability.h>
1da177e4
LT
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>
0296b228 34#include <linux/kobject.h>
20380731 35#include <linux/net.h>
1da177e4
LT
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>
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46#include <linux/nfs_fs.h>
47#include <linux/acpi.h>
1da177e4
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48
49#include <asm/uaccess.h>
50#include <asm/processor.h>
51
529bf6be
DS
52extern int proc_nr_files(ctl_table *table, int write, struct file *filp,
53 void __user *buffer, size_t *lenp, loff_t *ppos);
54
1da177e4
LT
55#if defined(CONFIG_SYSCTL)
56
57/* External variables not in a header file. */
58extern int C_A_D;
59extern int sysctl_overcommit_memory;
60extern int sysctl_overcommit_ratio;
fadd8fbd 61extern int sysctl_panic_on_oom;
1da177e4
LT
62extern int max_threads;
63extern int sysrq_enabled;
64extern int core_uses_pid;
d6e71144 65extern int suid_dumpable;
1da177e4
LT
66extern char core_pattern[];
67extern int cad_pid;
68extern int pid_max;
69extern int min_free_kbytes;
70extern int printk_ratelimit_jiffies;
71extern int printk_ratelimit_burst;
72extern int pid_max_min, pid_max_max;
9d0243bc 73extern int sysctl_drop_caches;
8ad4b1fb 74extern int percpu_pagelist_fraction;
bebfa101 75extern int compat_log;
1da177e4
LT
76
77#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
78int unknown_nmi_panic;
79extern int proc_unknown_nmi_panic(ctl_table *, int, struct file *,
80 void __user *, size_t *, loff_t *);
81#endif
82
83/* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
84static int maxolduid = 65535;
85static int minolduid;
8ad4b1fb 86static int min_percpu_pagelist_fract = 8;
1da177e4
LT
87
88static int ngroups_max = NGROUPS_MAX;
89
90#ifdef CONFIG_KMOD
91extern char modprobe_path[];
92#endif
1da177e4
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93#ifdef CONFIG_CHR_DEV_SG
94extern int sg_big_buff;
95#endif
96#ifdef CONFIG_SYSVIPC
97extern size_t shm_ctlmax;
98extern size_t shm_ctlall;
99extern int shm_ctlmni;
100extern int msg_ctlmax;
101extern int msg_ctlmnb;
102extern int msg_ctlmni;
103extern int sem_ctls[];
104#endif
105
106#ifdef __sparc__
107extern char reboot_command [];
108extern int stop_a_enabled;
109extern int scons_pwroff;
110#endif
111
112#ifdef __hppa__
113extern int pwrsw_enabled;
114extern int unaligned_enabled;
115#endif
116
347a8dc3 117#ifdef CONFIG_S390
1da177e4
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118#ifdef CONFIG_MATHEMU
119extern int sysctl_ieee_emulation_warnings;
120#endif
121extern int sysctl_userprocess_debug;
951f22d5 122extern int spin_retry;
1da177e4
LT
123#endif
124
125extern int sysctl_hz_timer;
126
127#ifdef CONFIG_BSD_PROCESS_ACCT
128extern int acct_parm[];
129#endif
130
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131#ifdef CONFIG_IA64
132extern int no_unaligned_warning;
133#endif
134
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135#ifdef CONFIG_RT_MUTEXES
136extern int max_lock_depth;
137#endif
138
1da177e4
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139static int parse_table(int __user *, int, void __user *, size_t __user *, void __user *, size_t,
140 ctl_table *, void **);
141static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
142 void __user *buffer, size_t *lenp, loff_t *ppos);
143
144static ctl_table root_table[];
145static struct ctl_table_header root_table_header =
146 { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
147
148static ctl_table kern_table[];
149static ctl_table vm_table[];
1da177e4
LT
150static ctl_table fs_table[];
151static ctl_table debug_table[];
152static ctl_table dev_table[];
153extern ctl_table random_table[];
154#ifdef CONFIG_UNIX98_PTYS
155extern ctl_table pty_table[];
156#endif
2d9048e2 157#ifdef CONFIG_INOTIFY_USER
0399cb08
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158extern ctl_table inotify_table[];
159#endif
1da177e4
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160
161#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
162int sysctl_legacy_va_layout;
163#endif
164
165/* /proc declarations: */
166
167#ifdef CONFIG_PROC_FS
168
169static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
170static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
171static int proc_opensys(struct inode *, struct file *);
172
173struct file_operations proc_sys_file_operations = {
174 .open = proc_opensys,
175 .read = proc_readsys,
176 .write = proc_writesys,
177};
178
179extern struct proc_dir_entry *proc_sys_root;
180
330d57fb 181static void register_proc_table(ctl_table *, struct proc_dir_entry *, void *);
1da177e4
LT
182static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
183#endif
184
185/* The default sysctl tables: */
186
187static ctl_table root_table[] = {
188 {
189 .ctl_name = CTL_KERN,
190 .procname = "kernel",
191 .mode = 0555,
192 .child = kern_table,
193 },
194 {
195 .ctl_name = CTL_VM,
196 .procname = "vm",
197 .mode = 0555,
198 .child = vm_table,
199 },
200#ifdef CONFIG_NET
201 {
202 .ctl_name = CTL_NET,
203 .procname = "net",
204 .mode = 0555,
205 .child = net_table,
206 },
207#endif
1da177e4
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208 {
209 .ctl_name = CTL_FS,
210 .procname = "fs",
211 .mode = 0555,
212 .child = fs_table,
213 },
214 {
215 .ctl_name = CTL_DEBUG,
216 .procname = "debug",
217 .mode = 0555,
218 .child = debug_table,
219 },
220 {
221 .ctl_name = CTL_DEV,
222 .procname = "dev",
223 .mode = 0555,
224 .child = dev_table,
225 },
0eeca283 226
1da177e4
LT
227 { .ctl_name = 0 }
228};
229
230static ctl_table kern_table[] = {
231 {
232 .ctl_name = KERN_OSTYPE,
233 .procname = "ostype",
234 .data = system_utsname.sysname,
235 .maxlen = sizeof(system_utsname.sysname),
236 .mode = 0444,
237 .proc_handler = &proc_doutsstring,
238 .strategy = &sysctl_string,
239 },
240 {
241 .ctl_name = KERN_OSRELEASE,
242 .procname = "osrelease",
243 .data = system_utsname.release,
244 .maxlen = sizeof(system_utsname.release),
245 .mode = 0444,
246 .proc_handler = &proc_doutsstring,
247 .strategy = &sysctl_string,
248 },
249 {
250 .ctl_name = KERN_VERSION,
251 .procname = "version",
252 .data = system_utsname.version,
253 .maxlen = sizeof(system_utsname.version),
254 .mode = 0444,
255 .proc_handler = &proc_doutsstring,
256 .strategy = &sysctl_string,
257 },
258 {
259 .ctl_name = KERN_NODENAME,
260 .procname = "hostname",
261 .data = system_utsname.nodename,
262 .maxlen = sizeof(system_utsname.nodename),
263 .mode = 0644,
264 .proc_handler = &proc_doutsstring,
265 .strategy = &sysctl_string,
266 },
267 {
268 .ctl_name = KERN_DOMAINNAME,
269 .procname = "domainname",
270 .data = system_utsname.domainname,
271 .maxlen = sizeof(system_utsname.domainname),
272 .mode = 0644,
273 .proc_handler = &proc_doutsstring,
274 .strategy = &sysctl_string,
275 },
276 {
277 .ctl_name = KERN_PANIC,
278 .procname = "panic",
279 .data = &panic_timeout,
280 .maxlen = sizeof(int),
281 .mode = 0644,
282 .proc_handler = &proc_dointvec,
283 },
284 {
285 .ctl_name = KERN_CORE_USES_PID,
286 .procname = "core_uses_pid",
287 .data = &core_uses_pid,
288 .maxlen = sizeof(int),
289 .mode = 0644,
290 .proc_handler = &proc_dointvec,
291 },
292 {
293 .ctl_name = KERN_CORE_PATTERN,
294 .procname = "core_pattern",
295 .data = core_pattern,
296 .maxlen = 64,
297 .mode = 0644,
298 .proc_handler = &proc_dostring,
299 .strategy = &sysctl_string,
300 },
301 {
302 .ctl_name = KERN_TAINTED,
303 .procname = "tainted",
304 .data = &tainted,
305 .maxlen = sizeof(int),
306 .mode = 0444,
307 .proc_handler = &proc_dointvec,
308 },
309 {
310 .ctl_name = KERN_CAP_BSET,
311 .procname = "cap-bound",
312 .data = &cap_bset,
313 .maxlen = sizeof(kernel_cap_t),
314 .mode = 0600,
315 .proc_handler = &proc_dointvec_bset,
316 },
317#ifdef CONFIG_BLK_DEV_INITRD
318 {
319 .ctl_name = KERN_REALROOTDEV,
320 .procname = "real-root-dev",
321 .data = &real_root_dev,
322 .maxlen = sizeof(int),
323 .mode = 0644,
324 .proc_handler = &proc_dointvec,
325 },
326#endif
327#ifdef __sparc__
328 {
329 .ctl_name = KERN_SPARC_REBOOT,
330 .procname = "reboot-cmd",
331 .data = reboot_command,
332 .maxlen = 256,
333 .mode = 0644,
334 .proc_handler = &proc_dostring,
335 .strategy = &sysctl_string,
336 },
337 {
338 .ctl_name = KERN_SPARC_STOP_A,
339 .procname = "stop-a",
340 .data = &stop_a_enabled,
341 .maxlen = sizeof (int),
342 .mode = 0644,
343 .proc_handler = &proc_dointvec,
344 },
345 {
346 .ctl_name = KERN_SPARC_SCONS_PWROFF,
347 .procname = "scons-poweroff",
348 .data = &scons_pwroff,
349 .maxlen = sizeof (int),
350 .mode = 0644,
351 .proc_handler = &proc_dointvec,
352 },
353#endif
354#ifdef __hppa__
355 {
356 .ctl_name = KERN_HPPA_PWRSW,
357 .procname = "soft-power",
358 .data = &pwrsw_enabled,
359 .maxlen = sizeof (int),
360 .mode = 0644,
361 .proc_handler = &proc_dointvec,
362 },
363 {
364 .ctl_name = KERN_HPPA_UNALIGNED,
365 .procname = "unaligned-trap",
366 .data = &unaligned_enabled,
367 .maxlen = sizeof (int),
368 .mode = 0644,
369 .proc_handler = &proc_dointvec,
370 },
371#endif
372 {
373 .ctl_name = KERN_CTLALTDEL,
374 .procname = "ctrl-alt-del",
375 .data = &C_A_D,
376 .maxlen = sizeof(int),
377 .mode = 0644,
378 .proc_handler = &proc_dointvec,
379 },
380 {
381 .ctl_name = KERN_PRINTK,
382 .procname = "printk",
383 .data = &console_loglevel,
384 .maxlen = 4*sizeof(int),
385 .mode = 0644,
386 .proc_handler = &proc_dointvec,
387 },
388#ifdef CONFIG_KMOD
389 {
390 .ctl_name = KERN_MODPROBE,
391 .procname = "modprobe",
392 .data = &modprobe_path,
393 .maxlen = KMOD_PATH_LEN,
394 .mode = 0644,
395 .proc_handler = &proc_dostring,
396 .strategy = &sysctl_string,
397 },
398#endif
57ae2508 399#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
1da177e4
LT
400 {
401 .ctl_name = KERN_HOTPLUG,
402 .procname = "hotplug",
312c004d
KS
403 .data = &uevent_helper,
404 .maxlen = UEVENT_HELPER_PATH_LEN,
1da177e4
LT
405 .mode = 0644,
406 .proc_handler = &proc_dostring,
407 .strategy = &sysctl_string,
408 },
409#endif
410#ifdef CONFIG_CHR_DEV_SG
411 {
412 .ctl_name = KERN_SG_BIG_BUFF,
413 .procname = "sg-big-buff",
414 .data = &sg_big_buff,
415 .maxlen = sizeof (int),
416 .mode = 0444,
417 .proc_handler = &proc_dointvec,
418 },
419#endif
420#ifdef CONFIG_BSD_PROCESS_ACCT
421 {
422 .ctl_name = KERN_ACCT,
423 .procname = "acct",
424 .data = &acct_parm,
425 .maxlen = 3*sizeof(int),
426 .mode = 0644,
427 .proc_handler = &proc_dointvec,
428 },
429#endif
430#ifdef CONFIG_SYSVIPC
431 {
432 .ctl_name = KERN_SHMMAX,
433 .procname = "shmmax",
434 .data = &shm_ctlmax,
435 .maxlen = sizeof (size_t),
436 .mode = 0644,
437 .proc_handler = &proc_doulongvec_minmax,
438 },
439 {
440 .ctl_name = KERN_SHMALL,
441 .procname = "shmall",
442 .data = &shm_ctlall,
443 .maxlen = sizeof (size_t),
444 .mode = 0644,
445 .proc_handler = &proc_doulongvec_minmax,
446 },
447 {
448 .ctl_name = KERN_SHMMNI,
449 .procname = "shmmni",
450 .data = &shm_ctlmni,
451 .maxlen = sizeof (int),
452 .mode = 0644,
453 .proc_handler = &proc_dointvec,
454 },
455 {
456 .ctl_name = KERN_MSGMAX,
457 .procname = "msgmax",
458 .data = &msg_ctlmax,
459 .maxlen = sizeof (int),
460 .mode = 0644,
461 .proc_handler = &proc_dointvec,
462 },
463 {
464 .ctl_name = KERN_MSGMNI,
465 .procname = "msgmni",
466 .data = &msg_ctlmni,
467 .maxlen = sizeof (int),
468 .mode = 0644,
469 .proc_handler = &proc_dointvec,
470 },
471 {
472 .ctl_name = KERN_MSGMNB,
473 .procname = "msgmnb",
474 .data = &msg_ctlmnb,
475 .maxlen = sizeof (int),
476 .mode = 0644,
477 .proc_handler = &proc_dointvec,
478 },
479 {
480 .ctl_name = KERN_SEM,
481 .procname = "sem",
482 .data = &sem_ctls,
483 .maxlen = 4*sizeof (int),
484 .mode = 0644,
485 .proc_handler = &proc_dointvec,
486 },
487#endif
488#ifdef CONFIG_MAGIC_SYSRQ
489 {
490 .ctl_name = KERN_SYSRQ,
491 .procname = "sysrq",
492 .data = &sysrq_enabled,
493 .maxlen = sizeof (int),
494 .mode = 0644,
495 .proc_handler = &proc_dointvec,
496 },
497#endif
498 {
499 .ctl_name = KERN_CADPID,
500 .procname = "cad_pid",
501 .data = &cad_pid,
502 .maxlen = sizeof (int),
503 .mode = 0600,
504 .proc_handler = &proc_dointvec,
505 },
506 {
507 .ctl_name = KERN_MAX_THREADS,
508 .procname = "threads-max",
509 .data = &max_threads,
510 .maxlen = sizeof(int),
511 .mode = 0644,
512 .proc_handler = &proc_dointvec,
513 },
514 {
515 .ctl_name = KERN_RANDOM,
516 .procname = "random",
517 .mode = 0555,
518 .child = random_table,
519 },
520#ifdef CONFIG_UNIX98_PTYS
521 {
522 .ctl_name = KERN_PTY,
523 .procname = "pty",
524 .mode = 0555,
525 .child = pty_table,
526 },
527#endif
528 {
529 .ctl_name = KERN_OVERFLOWUID,
530 .procname = "overflowuid",
531 .data = &overflowuid,
532 .maxlen = sizeof(int),
533 .mode = 0644,
534 .proc_handler = &proc_dointvec_minmax,
535 .strategy = &sysctl_intvec,
536 .extra1 = &minolduid,
537 .extra2 = &maxolduid,
538 },
539 {
540 .ctl_name = KERN_OVERFLOWGID,
541 .procname = "overflowgid",
542 .data = &overflowgid,
543 .maxlen = sizeof(int),
544 .mode = 0644,
545 .proc_handler = &proc_dointvec_minmax,
546 .strategy = &sysctl_intvec,
547 .extra1 = &minolduid,
548 .extra2 = &maxolduid,
549 },
347a8dc3 550#ifdef CONFIG_S390
1da177e4
LT
551#ifdef CONFIG_MATHEMU
552 {
553 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
554 .procname = "ieee_emulation_warnings",
555 .data = &sysctl_ieee_emulation_warnings,
556 .maxlen = sizeof(int),
557 .mode = 0644,
558 .proc_handler = &proc_dointvec,
559 },
560#endif
561#ifdef CONFIG_NO_IDLE_HZ
562 {
563 .ctl_name = KERN_HZ_TIMER,
564 .procname = "hz_timer",
565 .data = &sysctl_hz_timer,
566 .maxlen = sizeof(int),
567 .mode = 0644,
568 .proc_handler = &proc_dointvec,
569 },
570#endif
571 {
572 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
573 .procname = "userprocess_debug",
574 .data = &sysctl_userprocess_debug,
575 .maxlen = sizeof(int),
576 .mode = 0644,
577 .proc_handler = &proc_dointvec,
578 },
579#endif
580 {
581 .ctl_name = KERN_PIDMAX,
582 .procname = "pid_max",
583 .data = &pid_max,
584 .maxlen = sizeof (int),
585 .mode = 0644,
586 .proc_handler = &proc_dointvec_minmax,
587 .strategy = sysctl_intvec,
588 .extra1 = &pid_max_min,
589 .extra2 = &pid_max_max,
590 },
591 {
592 .ctl_name = KERN_PANIC_ON_OOPS,
593 .procname = "panic_on_oops",
594 .data = &panic_on_oops,
595 .maxlen = sizeof(int),
596 .mode = 0644,
597 .proc_handler = &proc_dointvec,
598 },
599 {
600 .ctl_name = KERN_PRINTK_RATELIMIT,
601 .procname = "printk_ratelimit",
602 .data = &printk_ratelimit_jiffies,
603 .maxlen = sizeof(int),
604 .mode = 0644,
605 .proc_handler = &proc_dointvec_jiffies,
606 .strategy = &sysctl_jiffies,
607 },
608 {
609 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
610 .procname = "printk_ratelimit_burst",
611 .data = &printk_ratelimit_burst,
612 .maxlen = sizeof(int),
613 .mode = 0644,
614 .proc_handler = &proc_dointvec,
615 },
616 {
617 .ctl_name = KERN_NGROUPS_MAX,
618 .procname = "ngroups_max",
619 .data = &ngroups_max,
620 .maxlen = sizeof (int),
621 .mode = 0444,
622 .proc_handler = &proc_dointvec,
623 },
624#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
625 {
626 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
627 .procname = "unknown_nmi_panic",
628 .data = &unknown_nmi_panic,
629 .maxlen = sizeof (int),
630 .mode = 0644,
631 .proc_handler = &proc_unknown_nmi_panic,
632 },
633#endif
634#if defined(CONFIG_X86)
635 {
636 .ctl_name = KERN_BOOTLOADER_TYPE,
637 .procname = "bootloader_type",
638 .data = &bootloader_type,
639 .maxlen = sizeof (int),
640 .mode = 0444,
641 .proc_handler = &proc_dointvec,
642 },
643#endif
7a9166e3 644#if defined(CONFIG_MMU)
1da177e4
LT
645 {
646 .ctl_name = KERN_RANDOMIZE,
647 .procname = "randomize_va_space",
648 .data = &randomize_va_space,
649 .maxlen = sizeof(int),
650 .mode = 0644,
651 .proc_handler = &proc_dointvec,
652 },
7a9166e3 653#endif
0152fb37 654#if defined(CONFIG_S390) && defined(CONFIG_SMP)
951f22d5
MS
655 {
656 .ctl_name = KERN_SPIN_RETRY,
657 .procname = "spin_retry",
658 .data = &spin_retry,
659 .maxlen = sizeof (int),
660 .mode = 0644,
661 .proc_handler = &proc_dointvec,
662 },
c255d844
PM
663#endif
664#ifdef CONFIG_ACPI_SLEEP
665 {
666 .ctl_name = KERN_ACPI_VIDEO_FLAGS,
667 .procname = "acpi_video_flags",
668 .data = &acpi_video_flags,
669 .maxlen = sizeof (unsigned long),
670 .mode = 0644,
7f99f06f 671 .proc_handler = &proc_doulongvec_minmax,
c255d844 672 },
d2b176ed
JS
673#endif
674#ifdef CONFIG_IA64
675 {
676 .ctl_name = KERN_IA64_UNALIGNED,
677 .procname = "ignore-unaligned-usertrap",
678 .data = &no_unaligned_warning,
679 .maxlen = sizeof (int),
680 .mode = 0644,
681 .proc_handler = &proc_dointvec,
682 },
bebfa101
AK
683#endif
684#ifdef CONFIG_COMPAT
685 {
686 .ctl_name = KERN_COMPAT_LOG,
687 .procname = "compat-log",
688 .data = &compat_log,
689 .maxlen = sizeof (int),
690 .mode = 0644,
691 .proc_handler = &proc_dointvec,
692 },
951f22d5 693#endif
23f78d4a
IM
694#ifdef CONFIG_RT_MUTEXES
695 {
696 .ctl_name = KERN_MAX_LOCK_DEPTH,
697 .procname = "max_lock_depth",
698 .data = &max_lock_depth,
699 .maxlen = sizeof(int),
700 .mode = 0644,
701 .proc_handler = &proc_dointvec,
702 },
703#endif
704
1da177e4
LT
705 { .ctl_name = 0 }
706};
707
708/* Constants for minimum and maximum testing in vm_table.
709 We use these as one-element integer vectors. */
710static int zero;
711static int one_hundred = 100;
712
713
714static ctl_table vm_table[] = {
715 {
716 .ctl_name = VM_OVERCOMMIT_MEMORY,
717 .procname = "overcommit_memory",
718 .data = &sysctl_overcommit_memory,
719 .maxlen = sizeof(sysctl_overcommit_memory),
720 .mode = 0644,
721 .proc_handler = &proc_dointvec,
722 },
fadd8fbd
KH
723 {
724 .ctl_name = VM_PANIC_ON_OOM,
725 .procname = "panic_on_oom",
726 .data = &sysctl_panic_on_oom,
727 .maxlen = sizeof(sysctl_panic_on_oom),
728 .mode = 0644,
729 .proc_handler = &proc_dointvec,
730 },
1da177e4
LT
731 {
732 .ctl_name = VM_OVERCOMMIT_RATIO,
733 .procname = "overcommit_ratio",
734 .data = &sysctl_overcommit_ratio,
735 .maxlen = sizeof(sysctl_overcommit_ratio),
736 .mode = 0644,
737 .proc_handler = &proc_dointvec,
738 },
739 {
740 .ctl_name = VM_PAGE_CLUSTER,
741 .procname = "page-cluster",
742 .data = &page_cluster,
743 .maxlen = sizeof(int),
744 .mode = 0644,
745 .proc_handler = &proc_dointvec,
746 },
747 {
748 .ctl_name = VM_DIRTY_BACKGROUND,
749 .procname = "dirty_background_ratio",
750 .data = &dirty_background_ratio,
751 .maxlen = sizeof(dirty_background_ratio),
752 .mode = 0644,
753 .proc_handler = &proc_dointvec_minmax,
754 .strategy = &sysctl_intvec,
755 .extra1 = &zero,
756 .extra2 = &one_hundred,
757 },
758 {
759 .ctl_name = VM_DIRTY_RATIO,
760 .procname = "dirty_ratio",
761 .data = &vm_dirty_ratio,
762 .maxlen = sizeof(vm_dirty_ratio),
763 .mode = 0644,
764 .proc_handler = &proc_dointvec_minmax,
765 .strategy = &sysctl_intvec,
766 .extra1 = &zero,
767 .extra2 = &one_hundred,
768 },
769 {
770 .ctl_name = VM_DIRTY_WB_CS,
771 .procname = "dirty_writeback_centisecs",
f6ef9438
BS
772 .data = &dirty_writeback_interval,
773 .maxlen = sizeof(dirty_writeback_interval),
1da177e4
LT
774 .mode = 0644,
775 .proc_handler = &dirty_writeback_centisecs_handler,
776 },
777 {
778 .ctl_name = VM_DIRTY_EXPIRE_CS,
779 .procname = "dirty_expire_centisecs",
f6ef9438
BS
780 .data = &dirty_expire_interval,
781 .maxlen = sizeof(dirty_expire_interval),
1da177e4 782 .mode = 0644,
f6ef9438 783 .proc_handler = &proc_dointvec_userhz_jiffies,
1da177e4
LT
784 },
785 {
786 .ctl_name = VM_NR_PDFLUSH_THREADS,
787 .procname = "nr_pdflush_threads",
788 .data = &nr_pdflush_threads,
789 .maxlen = sizeof nr_pdflush_threads,
790 .mode = 0444 /* read-only*/,
791 .proc_handler = &proc_dointvec,
792 },
793 {
794 .ctl_name = VM_SWAPPINESS,
795 .procname = "swappiness",
796 .data = &vm_swappiness,
797 .maxlen = sizeof(vm_swappiness),
798 .mode = 0644,
799 .proc_handler = &proc_dointvec_minmax,
800 .strategy = &sysctl_intvec,
801 .extra1 = &zero,
802 .extra2 = &one_hundred,
803 },
804#ifdef CONFIG_HUGETLB_PAGE
805 {
806 .ctl_name = VM_HUGETLB_PAGES,
807 .procname = "nr_hugepages",
808 .data = &max_huge_pages,
809 .maxlen = sizeof(unsigned long),
810 .mode = 0644,
811 .proc_handler = &hugetlb_sysctl_handler,
812 .extra1 = (void *)&hugetlb_zero,
813 .extra2 = (void *)&hugetlb_infinity,
814 },
815 {
816 .ctl_name = VM_HUGETLB_GROUP,
817 .procname = "hugetlb_shm_group",
818 .data = &sysctl_hugetlb_shm_group,
819 .maxlen = sizeof(gid_t),
820 .mode = 0644,
821 .proc_handler = &proc_dointvec,
822 },
823#endif
824 {
825 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
826 .procname = "lowmem_reserve_ratio",
827 .data = &sysctl_lowmem_reserve_ratio,
828 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
829 .mode = 0644,
830 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
831 .strategy = &sysctl_intvec,
832 },
9d0243bc
AM
833 {
834 .ctl_name = VM_DROP_PAGECACHE,
835 .procname = "drop_caches",
836 .data = &sysctl_drop_caches,
837 .maxlen = sizeof(int),
838 .mode = 0644,
839 .proc_handler = drop_caches_sysctl_handler,
840 .strategy = &sysctl_intvec,
841 },
1da177e4
LT
842 {
843 .ctl_name = VM_MIN_FREE_KBYTES,
844 .procname = "min_free_kbytes",
845 .data = &min_free_kbytes,
846 .maxlen = sizeof(min_free_kbytes),
847 .mode = 0644,
848 .proc_handler = &min_free_kbytes_sysctl_handler,
849 .strategy = &sysctl_intvec,
850 .extra1 = &zero,
851 },
8ad4b1fb
RS
852 {
853 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
854 .procname = "percpu_pagelist_fraction",
855 .data = &percpu_pagelist_fraction,
856 .maxlen = sizeof(percpu_pagelist_fraction),
857 .mode = 0644,
858 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
859 .strategy = &sysctl_intvec,
860 .extra1 = &min_percpu_pagelist_fract,
861 },
1da177e4
LT
862#ifdef CONFIG_MMU
863 {
864 .ctl_name = VM_MAX_MAP_COUNT,
865 .procname = "max_map_count",
866 .data = &sysctl_max_map_count,
867 .maxlen = sizeof(sysctl_max_map_count),
868 .mode = 0644,
869 .proc_handler = &proc_dointvec
870 },
871#endif
872 {
873 .ctl_name = VM_LAPTOP_MODE,
874 .procname = "laptop_mode",
875 .data = &laptop_mode,
876 .maxlen = sizeof(laptop_mode),
877 .mode = 0644,
ed5b43f1
BS
878 .proc_handler = &proc_dointvec_jiffies,
879 .strategy = &sysctl_jiffies,
1da177e4
LT
880 },
881 {
882 .ctl_name = VM_BLOCK_DUMP,
883 .procname = "block_dump",
884 .data = &block_dump,
885 .maxlen = sizeof(block_dump),
886 .mode = 0644,
887 .proc_handler = &proc_dointvec,
888 .strategy = &sysctl_intvec,
889 .extra1 = &zero,
890 },
891 {
892 .ctl_name = VM_VFS_CACHE_PRESSURE,
893 .procname = "vfs_cache_pressure",
894 .data = &sysctl_vfs_cache_pressure,
895 .maxlen = sizeof(sysctl_vfs_cache_pressure),
896 .mode = 0644,
897 .proc_handler = &proc_dointvec,
898 .strategy = &sysctl_intvec,
899 .extra1 = &zero,
900 },
901#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
902 {
903 .ctl_name = VM_LEGACY_VA_LAYOUT,
904 .procname = "legacy_va_layout",
905 .data = &sysctl_legacy_va_layout,
906 .maxlen = sizeof(sysctl_legacy_va_layout),
907 .mode = 0644,
908 .proc_handler = &proc_dointvec,
909 .strategy = &sysctl_intvec,
910 .extra1 = &zero,
911 },
912#endif
913#ifdef CONFIG_SWAP
914 {
915 .ctl_name = VM_SWAP_TOKEN_TIMEOUT,
916 .procname = "swap_token_timeout",
917 .data = &swap_token_default_timeout,
918 .maxlen = sizeof(swap_token_default_timeout),
919 .mode = 0644,
920 .proc_handler = &proc_dointvec_jiffies,
921 .strategy = &sysctl_jiffies,
922 },
1743660b
CL
923#endif
924#ifdef CONFIG_NUMA
925 {
926 .ctl_name = VM_ZONE_RECLAIM_MODE,
927 .procname = "zone_reclaim_mode",
928 .data = &zone_reclaim_mode,
929 .maxlen = sizeof(zone_reclaim_mode),
930 .mode = 0644,
931 .proc_handler = &proc_dointvec,
c84db23c
CL
932 .strategy = &sysctl_intvec,
933 .extra1 = &zero,
1743660b 934 },
9614634f
CL
935 {
936 .ctl_name = VM_MIN_UNMAPPED,
937 .procname = "min_unmapped_ratio",
938 .data = &sysctl_min_unmapped_ratio,
939 .maxlen = sizeof(sysctl_min_unmapped_ratio),
940 .mode = 0644,
941 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
942 .strategy = &sysctl_intvec,
943 .extra1 = &zero,
944 .extra2 = &one_hundred,
945 },
e6e5494c
IM
946#endif
947#ifdef CONFIG_X86_32
948 {
949 .ctl_name = VM_VDSO_ENABLED,
950 .procname = "vdso_enabled",
951 .data = &vdso_enabled,
952 .maxlen = sizeof(vdso_enabled),
953 .mode = 0644,
954 .proc_handler = &proc_dointvec,
955 .strategy = &sysctl_intvec,
956 .extra1 = &zero,
957 },
1da177e4
LT
958#endif
959 { .ctl_name = 0 }
960};
961
1da177e4
LT
962static ctl_table fs_table[] = {
963 {
964 .ctl_name = FS_NRINODE,
965 .procname = "inode-nr",
966 .data = &inodes_stat,
967 .maxlen = 2*sizeof(int),
968 .mode = 0444,
969 .proc_handler = &proc_dointvec,
970 },
971 {
972 .ctl_name = FS_STATINODE,
973 .procname = "inode-state",
974 .data = &inodes_stat,
975 .maxlen = 7*sizeof(int),
976 .mode = 0444,
977 .proc_handler = &proc_dointvec,
978 },
979 {
980 .ctl_name = FS_NRFILE,
981 .procname = "file-nr",
982 .data = &files_stat,
983 .maxlen = 3*sizeof(int),
984 .mode = 0444,
529bf6be 985 .proc_handler = &proc_nr_files,
1da177e4
LT
986 },
987 {
988 .ctl_name = FS_MAXFILE,
989 .procname = "file-max",
990 .data = &files_stat.max_files,
991 .maxlen = sizeof(int),
992 .mode = 0644,
993 .proc_handler = &proc_dointvec,
994 },
995 {
996 .ctl_name = FS_DENTRY,
997 .procname = "dentry-state",
998 .data = &dentry_stat,
999 .maxlen = 6*sizeof(int),
1000 .mode = 0444,
1001 .proc_handler = &proc_dointvec,
1002 },
1003 {
1004 .ctl_name = FS_OVERFLOWUID,
1005 .procname = "overflowuid",
1006 .data = &fs_overflowuid,
1007 .maxlen = sizeof(int),
1008 .mode = 0644,
1009 .proc_handler = &proc_dointvec_minmax,
1010 .strategy = &sysctl_intvec,
1011 .extra1 = &minolduid,
1012 .extra2 = &maxolduid,
1013 },
1014 {
1015 .ctl_name = FS_OVERFLOWGID,
1016 .procname = "overflowgid",
1017 .data = &fs_overflowgid,
1018 .maxlen = sizeof(int),
1019 .mode = 0644,
1020 .proc_handler = &proc_dointvec_minmax,
1021 .strategy = &sysctl_intvec,
1022 .extra1 = &minolduid,
1023 .extra2 = &maxolduid,
1024 },
1025 {
1026 .ctl_name = FS_LEASES,
1027 .procname = "leases-enable",
1028 .data = &leases_enable,
1029 .maxlen = sizeof(int),
1030 .mode = 0644,
1031 .proc_handler = &proc_dointvec,
1032 },
1033#ifdef CONFIG_DNOTIFY
1034 {
1035 .ctl_name = FS_DIR_NOTIFY,
1036 .procname = "dir-notify-enable",
1037 .data = &dir_notify_enable,
1038 .maxlen = sizeof(int),
1039 .mode = 0644,
1040 .proc_handler = &proc_dointvec,
1041 },
1042#endif
1043#ifdef CONFIG_MMU
1044 {
1045 .ctl_name = FS_LEASE_TIME,
1046 .procname = "lease-break-time",
1047 .data = &lease_break_time,
1048 .maxlen = sizeof(int),
1049 .mode = 0644,
1050 .proc_handler = &proc_dointvec,
1051 },
1052 {
1053 .ctl_name = FS_AIO_NR,
1054 .procname = "aio-nr",
1055 .data = &aio_nr,
1056 .maxlen = sizeof(aio_nr),
1057 .mode = 0444,
d55b5fda 1058 .proc_handler = &proc_doulongvec_minmax,
1da177e4
LT
1059 },
1060 {
1061 .ctl_name = FS_AIO_MAX_NR,
1062 .procname = "aio-max-nr",
1063 .data = &aio_max_nr,
1064 .maxlen = sizeof(aio_max_nr),
1065 .mode = 0644,
d55b5fda 1066 .proc_handler = &proc_doulongvec_minmax,
1da177e4 1067 },
2d9048e2 1068#ifdef CONFIG_INOTIFY_USER
0399cb08
RL
1069 {
1070 .ctl_name = FS_INOTIFY,
1071 .procname = "inotify",
1072 .mode = 0555,
1073 .child = inotify_table,
1074 },
1075#endif
1da177e4 1076#endif
d6e71144
AC
1077 {
1078 .ctl_name = KERN_SETUID_DUMPABLE,
1079 .procname = "suid_dumpable",
1080 .data = &suid_dumpable,
1081 .maxlen = sizeof(int),
1082 .mode = 0644,
1083 .proc_handler = &proc_dointvec,
1084 },
1da177e4
LT
1085 { .ctl_name = 0 }
1086};
1087
1088static ctl_table debug_table[] = {
1089 { .ctl_name = 0 }
1090};
1091
1092static ctl_table dev_table[] = {
1093 { .ctl_name = 0 }
0eeca283 1094};
1da177e4
LT
1095
1096extern void init_irq_proc (void);
1097
330d57fb
AV
1098static DEFINE_SPINLOCK(sysctl_lock);
1099
1100/* called under sysctl_lock */
1101static int use_table(struct ctl_table_header *p)
1102{
1103 if (unlikely(p->unregistering))
1104 return 0;
1105 p->used++;
1106 return 1;
1107}
1108
1109/* called under sysctl_lock */
1110static void unuse_table(struct ctl_table_header *p)
1111{
1112 if (!--p->used)
1113 if (unlikely(p->unregistering))
1114 complete(p->unregistering);
1115}
1116
1117/* called under sysctl_lock, will reacquire if has to wait */
1118static void start_unregistering(struct ctl_table_header *p)
1119{
1120 /*
1121 * if p->used is 0, nobody will ever touch that entry again;
1122 * we'll eliminate all paths to it before dropping sysctl_lock
1123 */
1124 if (unlikely(p->used)) {
1125 struct completion wait;
1126 init_completion(&wait);
1127 p->unregistering = &wait;
1128 spin_unlock(&sysctl_lock);
1129 wait_for_completion(&wait);
1130 spin_lock(&sysctl_lock);
1131 }
1132 /*
1133 * do not remove from the list until nobody holds it; walking the
1134 * list in do_sysctl() relies on that.
1135 */
1136 list_del_init(&p->ctl_entry);
1137}
1138
1da177e4
LT
1139void __init sysctl_init(void)
1140{
1141#ifdef CONFIG_PROC_FS
330d57fb 1142 register_proc_table(root_table, proc_sys_root, &root_table_header);
1da177e4
LT
1143 init_irq_proc();
1144#endif
1145}
1146
1147int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1148 void __user *newval, size_t newlen)
1149{
1150 struct list_head *tmp;
330d57fb 1151 int error = -ENOTDIR;
1da177e4
LT
1152
1153 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1154 return -ENOTDIR;
1155 if (oldval) {
1156 int old_len;
1157 if (!oldlenp || get_user(old_len, oldlenp))
1158 return -EFAULT;
1159 }
330d57fb 1160 spin_lock(&sysctl_lock);
1da177e4
LT
1161 tmp = &root_table_header.ctl_entry;
1162 do {
1163 struct ctl_table_header *head =
1164 list_entry(tmp, struct ctl_table_header, ctl_entry);
1165 void *context = NULL;
330d57fb
AV
1166
1167 if (!use_table(head))
1168 continue;
1169
1170 spin_unlock(&sysctl_lock);
1171
1172 error = parse_table(name, nlen, oldval, oldlenp,
1da177e4
LT
1173 newval, newlen, head->ctl_table,
1174 &context);
5a6b454f 1175 kfree(context);
330d57fb
AV
1176
1177 spin_lock(&sysctl_lock);
1178 unuse_table(head);
1da177e4 1179 if (error != -ENOTDIR)
330d57fb
AV
1180 break;
1181 } while ((tmp = tmp->next) != &root_table_header.ctl_entry);
1182 spin_unlock(&sysctl_lock);
1183 return error;
1da177e4
LT
1184}
1185
1186asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1187{
1188 struct __sysctl_args tmp;
1189 int error;
1190
1191 if (copy_from_user(&tmp, args, sizeof(tmp)))
1192 return -EFAULT;
1193
1194 lock_kernel();
1195 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1196 tmp.newval, tmp.newlen);
1197 unlock_kernel();
1198 return error;
1199}
1200
1201/*
1202 * ctl_perm does NOT grant the superuser all rights automatically, because
1203 * some sysctl variables are readonly even to root.
1204 */
1205
1206static int test_perm(int mode, int op)
1207{
1208 if (!current->euid)
1209 mode >>= 6;
1210 else if (in_egroup_p(0))
1211 mode >>= 3;
1212 if ((mode & op & 0007) == op)
1213 return 0;
1214 return -EACCES;
1215}
1216
1217static inline int ctl_perm(ctl_table *table, int op)
1218{
1219 int error;
1220 error = security_sysctl(table, op);
1221 if (error)
1222 return error;
1223 return test_perm(table->mode, op);
1224}
1225
1226static int parse_table(int __user *name, int nlen,
1227 void __user *oldval, size_t __user *oldlenp,
1228 void __user *newval, size_t newlen,
1229 ctl_table *table, void **context)
1230{
1231 int n;
1232repeat:
1233 if (!nlen)
1234 return -ENOTDIR;
1235 if (get_user(n, name))
1236 return -EFAULT;
1237 for ( ; table->ctl_name; table++) {
1238 if (n == table->ctl_name || table->ctl_name == CTL_ANY) {
1239 int error;
1240 if (table->child) {
1241 if (ctl_perm(table, 001))
1242 return -EPERM;
1243 if (table->strategy) {
1244 error = table->strategy(
1245 table, name, nlen,
1246 oldval, oldlenp,
1247 newval, newlen, context);
1248 if (error)
1249 return error;
1250 }
1251 name++;
1252 nlen--;
1253 table = table->child;
1254 goto repeat;
1255 }
1256 error = do_sysctl_strategy(table, name, nlen,
1257 oldval, oldlenp,
1258 newval, newlen, context);
1259 return error;
1260 }
1261 }
1262 return -ENOTDIR;
1263}
1264
1265/* Perform the actual read/write of a sysctl table entry. */
1266int do_sysctl_strategy (ctl_table *table,
1267 int __user *name, int nlen,
1268 void __user *oldval, size_t __user *oldlenp,
1269 void __user *newval, size_t newlen, void **context)
1270{
1271 int op = 0, rc;
1272 size_t len;
1273
1274 if (oldval)
1275 op |= 004;
1276 if (newval)
1277 op |= 002;
1278 if (ctl_perm(table, op))
1279 return -EPERM;
1280
1281 if (table->strategy) {
1282 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1283 newval, newlen, context);
1284 if (rc < 0)
1285 return rc;
1286 if (rc > 0)
1287 return 0;
1288 }
1289
1290 /* If there is no strategy routine, or if the strategy returns
1291 * zero, proceed with automatic r/w */
1292 if (table->data && table->maxlen) {
1293 if (oldval && oldlenp) {
1294 if (get_user(len, oldlenp))
1295 return -EFAULT;
1296 if (len) {
1297 if (len > table->maxlen)
1298 len = table->maxlen;
1299 if(copy_to_user(oldval, table->data, len))
1300 return -EFAULT;
1301 if(put_user(len, oldlenp))
1302 return -EFAULT;
1303 }
1304 }
1305 if (newval && newlen) {
1306 len = newlen;
1307 if (len > table->maxlen)
1308 len = table->maxlen;
1309 if(copy_from_user(table->data, newval, len))
1310 return -EFAULT;
1311 }
1312 }
1313 return 0;
1314}
1315
1316/**
1317 * register_sysctl_table - register a sysctl hierarchy
1318 * @table: the top-level table structure
1319 * @insert_at_head: whether the entry should be inserted in front or at the end
1320 *
1321 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1322 * array. An entry with a ctl_name of 0 terminates the table.
1323 *
1324 * The members of the &ctl_table structure are used as follows:
1325 *
1326 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1327 * must be unique within that level of sysctl
1328 *
1329 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1330 * enter a sysctl file
1331 *
1332 * data - a pointer to data for use by proc_handler
1333 *
1334 * maxlen - the maximum size in bytes of the data
1335 *
1336 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1337 *
1338 * child - a pointer to the child sysctl table if this entry is a directory, or
1339 * %NULL.
1340 *
1341 * proc_handler - the text handler routine (described below)
1342 *
1343 * strategy - the strategy routine (described below)
1344 *
1345 * de - for internal use by the sysctl routines
1346 *
1347 * extra1, extra2 - extra pointers usable by the proc handler routines
1348 *
1349 * Leaf nodes in the sysctl tree will be represented by a single file
1350 * under /proc; non-leaf nodes will be represented by directories.
1351 *
1352 * sysctl(2) can automatically manage read and write requests through
1353 * the sysctl table. The data and maxlen fields of the ctl_table
1354 * struct enable minimal validation of the values being written to be
1355 * performed, and the mode field allows minimal authentication.
1356 *
1357 * More sophisticated management can be enabled by the provision of a
1358 * strategy routine with the table entry. This will be called before
1359 * any automatic read or write of the data is performed.
1360 *
1361 * The strategy routine may return
1362 *
1363 * < 0 - Error occurred (error is passed to user process)
1364 *
1365 * 0 - OK - proceed with automatic read or write.
1366 *
1367 * > 0 - OK - read or write has been done by the strategy routine, so
1368 * return immediately.
1369 *
1370 * There must be a proc_handler routine for any terminal nodes
1371 * mirrored under /proc/sys (non-terminals are handled by a built-in
1372 * directory handler). Several default handlers are available to
1373 * cover common cases -
1374 *
1375 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1376 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1377 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1378 *
1379 * It is the handler's job to read the input buffer from user memory
1380 * and process it. The handler should return 0 on success.
1381 *
1382 * This routine returns %NULL on a failure to register, and a pointer
1383 * to the table header on success.
1384 */
1385struct ctl_table_header *register_sysctl_table(ctl_table * table,
1386 int insert_at_head)
1387{
1388 struct ctl_table_header *tmp;
1389 tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1390 if (!tmp)
1391 return NULL;
1392 tmp->ctl_table = table;
1393 INIT_LIST_HEAD(&tmp->ctl_entry);
330d57fb
AV
1394 tmp->used = 0;
1395 tmp->unregistering = NULL;
1396 spin_lock(&sysctl_lock);
1da177e4
LT
1397 if (insert_at_head)
1398 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
1399 else
1400 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
330d57fb 1401 spin_unlock(&sysctl_lock);
1da177e4 1402#ifdef CONFIG_PROC_FS
330d57fb 1403 register_proc_table(table, proc_sys_root, tmp);
1da177e4
LT
1404#endif
1405 return tmp;
1406}
1407
1408/**
1409 * unregister_sysctl_table - unregister a sysctl table hierarchy
1410 * @header: the header returned from register_sysctl_table
1411 *
1412 * Unregisters the sysctl table and all children. proc entries may not
1413 * actually be removed until they are no longer used by anyone.
1414 */
1415void unregister_sysctl_table(struct ctl_table_header * header)
1416{
330d57fb
AV
1417 might_sleep();
1418 spin_lock(&sysctl_lock);
1419 start_unregistering(header);
1da177e4
LT
1420#ifdef CONFIG_PROC_FS
1421 unregister_proc_table(header->ctl_table, proc_sys_root);
1422#endif
330d57fb 1423 spin_unlock(&sysctl_lock);
1da177e4
LT
1424 kfree(header);
1425}
1426
1427/*
1428 * /proc/sys support
1429 */
1430
1431#ifdef CONFIG_PROC_FS
1432
1433/* Scan the sysctl entries in table and add them all into /proc */
330d57fb 1434static void register_proc_table(ctl_table * table, struct proc_dir_entry *root, void *set)
1da177e4
LT
1435{
1436 struct proc_dir_entry *de;
1437 int len;
1438 mode_t mode;
1439
1440 for (; table->ctl_name; table++) {
1441 /* Can't do anything without a proc name. */
1442 if (!table->procname)
1443 continue;
1444 /* Maybe we can't do anything with it... */
1445 if (!table->proc_handler && !table->child) {
1446 printk(KERN_WARNING "SYSCTL: Can't register %s\n",
1447 table->procname);
1448 continue;
1449 }
1450
1451 len = strlen(table->procname);
1452 mode = table->mode;
1453
1454 de = NULL;
1455 if (table->proc_handler)
1456 mode |= S_IFREG;
1457 else {
1458 mode |= S_IFDIR;
1459 for (de = root->subdir; de; de = de->next) {
1460 if (proc_match(len, table->procname, de))
1461 break;
1462 }
1463 /* If the subdir exists already, de is non-NULL */
1464 }
1465
1466 if (!de) {
1467 de = create_proc_entry(table->procname, mode, root);
1468 if (!de)
1469 continue;
330d57fb 1470 de->set = set;
1da177e4
LT
1471 de->data = (void *) table;
1472 if (table->proc_handler)
1473 de->proc_fops = &proc_sys_file_operations;
1474 }
1475 table->de = de;
1476 if (de->mode & S_IFDIR)
330d57fb 1477 register_proc_table(table->child, de, set);
1da177e4
LT
1478 }
1479}
1480
1481/*
1482 * Unregister a /proc sysctl table and any subdirectories.
1483 */
1484static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
1485{
1486 struct proc_dir_entry *de;
1487 for (; table->ctl_name; table++) {
1488 if (!(de = table->de))
1489 continue;
1490 if (de->mode & S_IFDIR) {
1491 if (!table->child) {
1492 printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
1493 continue;
1494 }
1495 unregister_proc_table(table->child, de);
1496
1497 /* Don't unregister directories which still have entries.. */
1498 if (de->subdir)
1499 continue;
1500 }
1501
330d57fb
AV
1502 /*
1503 * In any case, mark the entry as goner; we'll keep it
1504 * around if it's busy, but we'll know to do nothing with
1505 * its fields. We are under sysctl_lock here.
1506 */
1507 de->data = NULL;
1508
1da177e4
LT
1509 /* Don't unregister proc entries that are still being used.. */
1510 if (atomic_read(&de->count))
1511 continue;
1512
1513 table->de = NULL;
1514 remove_proc_entry(table->procname, root);
1515 }
1516}
1517
1518static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
1519 size_t count, loff_t *ppos)
1520{
1521 int op;
330d57fb 1522 struct proc_dir_entry *de = PDE(file->f_dentry->d_inode);
1da177e4
LT
1523 struct ctl_table *table;
1524 size_t res;
330d57fb 1525 ssize_t error = -ENOTDIR;
1da177e4 1526
330d57fb
AV
1527 spin_lock(&sysctl_lock);
1528 if (de && de->data && use_table(de->set)) {
1529 /*
1530 * at that point we know that sysctl was not unregistered
1531 * and won't be until we finish
1532 */
1533 spin_unlock(&sysctl_lock);
1534 table = (struct ctl_table *) de->data;
1535 if (!table || !table->proc_handler)
1536 goto out;
1537 error = -EPERM;
1538 op = (write ? 002 : 004);
1539 if (ctl_perm(table, op))
1540 goto out;
1541
1542 /* careful: calling conventions are nasty here */
1543 res = count;
1544 error = (*table->proc_handler)(table, write, file,
1545 buf, &res, ppos);
1546 if (!error)
1547 error = res;
1548 out:
1549 spin_lock(&sysctl_lock);
1550 unuse_table(de->set);
1551 }
1552 spin_unlock(&sysctl_lock);
1553 return error;
1da177e4
LT
1554}
1555
1556static int proc_opensys(struct inode *inode, struct file *file)
1557{
1558 if (file->f_mode & FMODE_WRITE) {
1559 /*
1560 * sysctl entries that are not writable,
1561 * are _NOT_ writable, capabilities or not.
1562 */
1563 if (!(inode->i_mode & S_IWUSR))
1564 return -EPERM;
1565 }
1566
1567 return 0;
1568}
1569
1570static ssize_t proc_readsys(struct file * file, char __user * buf,
1571 size_t count, loff_t *ppos)
1572{
1573 return do_rw_proc(0, file, buf, count, ppos);
1574}
1575
1576static ssize_t proc_writesys(struct file * file, const char __user * buf,
1577 size_t count, loff_t *ppos)
1578{
1579 return do_rw_proc(1, file, (char __user *) buf, count, ppos);
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 */
1600int proc_dostring(ctl_table *table, int write, struct file *filp,
1601 void __user *buffer, size_t *lenp, loff_t *ppos)
1602{
1603 size_t len;
1604 char __user *p;
1605 char c;
1606
1607 if (!table->data || !table->maxlen || !*lenp ||
1608 (*ppos && !write)) {
1609 *lenp = 0;
1610 return 0;
1611 }
1612
1613 if (write) {
1614 len = 0;
1615 p = buffer;
1616 while (len < *lenp) {
1617 if (get_user(c, p++))
1618 return -EFAULT;
1619 if (c == 0 || c == '\n')
1620 break;
1621 len++;
1622 }
1623 if (len >= table->maxlen)
1624 len = table->maxlen-1;
1625 if(copy_from_user(table->data, buffer, len))
1626 return -EFAULT;
1627 ((char *) table->data)[len] = 0;
1628 *ppos += *lenp;
1629 } else {
1630 len = strlen(table->data);
1631 if (len > table->maxlen)
1632 len = table->maxlen;
1633 if (len > *lenp)
1634 len = *lenp;
1635 if (len)
1636 if(copy_to_user(buffer, table->data, len))
1637 return -EFAULT;
1638 if (len < *lenp) {
1639 if(put_user('\n', ((char __user *) buffer) + len))
1640 return -EFAULT;
1641 len++;
1642 }
1643 *lenp = len;
1644 *ppos += len;
1645 }
1646 return 0;
1647}
1648
1649/*
1650 * Special case of dostring for the UTS structure. This has locks
1651 * to observe. Should this be in kernel/sys.c ????
1652 */
1653
1654static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
1655 void __user *buffer, size_t *lenp, loff_t *ppos)
1656{
1657 int r;
1658
1659 if (!write) {
1660 down_read(&uts_sem);
1661 r=proc_dostring(table,0,filp,buffer,lenp, ppos);
1662 up_read(&uts_sem);
1663 } else {
1664 down_write(&uts_sem);
1665 r=proc_dostring(table,1,filp,buffer,lenp, ppos);
1666 up_write(&uts_sem);
1667 }
1668 return r;
1669}
1670
1671static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1672 int *valp,
1673 int write, void *data)
1674{
1675 if (write) {
1676 *valp = *negp ? -*lvalp : *lvalp;
1677 } else {
1678 int val = *valp;
1679 if (val < 0) {
1680 *negp = -1;
1681 *lvalp = (unsigned long)-val;
1682 } else {
1683 *negp = 0;
1684 *lvalp = (unsigned long)val;
1685 }
1686 }
1687 return 0;
1688}
1689
1690static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1691 void __user *buffer, size_t *lenp, loff_t *ppos,
1692 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1693 int write, void *data),
1694 void *data)
1695{
1696#define TMPBUFLEN 21
1697 int *i, vleft, first=1, neg, val;
1698 unsigned long lval;
1699 size_t left, len;
1700
1701 char buf[TMPBUFLEN], *p;
1702 char __user *s = buffer;
1703
1704 if (!table->data || !table->maxlen || !*lenp ||
1705 (*ppos && !write)) {
1706 *lenp = 0;
1707 return 0;
1708 }
1709
1710 i = (int *) table->data;
1711 vleft = table->maxlen / sizeof(*i);
1712 left = *lenp;
1713
1714 if (!conv)
1715 conv = do_proc_dointvec_conv;
1716
1717 for (; left && vleft--; i++, first=0) {
1718 if (write) {
1719 while (left) {
1720 char c;
1721 if (get_user(c, s))
1722 return -EFAULT;
1723 if (!isspace(c))
1724 break;
1725 left--;
1726 s++;
1727 }
1728 if (!left)
1729 break;
1730 neg = 0;
1731 len = left;
1732 if (len > sizeof(buf) - 1)
1733 len = sizeof(buf) - 1;
1734 if (copy_from_user(buf, s, len))
1735 return -EFAULT;
1736 buf[len] = 0;
1737 p = buf;
1738 if (*p == '-' && left > 1) {
1739 neg = 1;
1740 left--, p++;
1741 }
1742 if (*p < '0' || *p > '9')
1743 break;
1744
1745 lval = simple_strtoul(p, &p, 0);
1746
1747 len = p-buf;
1748 if ((len < left) && *p && !isspace(*p))
1749 break;
1750 if (neg)
1751 val = -val;
1752 s += len;
1753 left -= len;
1754
1755 if (conv(&neg, &lval, i, 1, data))
1756 break;
1757 } else {
1758 p = buf;
1759 if (!first)
1760 *p++ = '\t';
1761
1762 if (conv(&neg, &lval, i, 0, data))
1763 break;
1764
1765 sprintf(p, "%s%lu", neg ? "-" : "", lval);
1766 len = strlen(buf);
1767 if (len > left)
1768 len = left;
1769 if(copy_to_user(s, buf, len))
1770 return -EFAULT;
1771 left -= len;
1772 s += len;
1773 }
1774 }
1775
1776 if (!write && !first && left) {
1777 if(put_user('\n', s))
1778 return -EFAULT;
1779 left--, s++;
1780 }
1781 if (write) {
1782 while (left) {
1783 char c;
1784 if (get_user(c, s++))
1785 return -EFAULT;
1786 if (!isspace(c))
1787 break;
1788 left--;
1789 }
1790 }
1791 if (write && first)
1792 return -EINVAL;
1793 *lenp -= left;
1794 *ppos += *lenp;
1795 return 0;
1796#undef TMPBUFLEN
1797}
1798
1799/**
1800 * proc_dointvec - read a vector of integers
1801 * @table: the sysctl table
1802 * @write: %TRUE if this is a write to the sysctl file
1803 * @filp: the file structure
1804 * @buffer: the user buffer
1805 * @lenp: the size of the user buffer
1806 * @ppos: file position
1807 *
1808 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1809 * values from/to the user buffer, treated as an ASCII string.
1810 *
1811 * Returns 0 on success.
1812 */
1813int proc_dointvec(ctl_table *table, int write, struct file *filp,
1814 void __user *buffer, size_t *lenp, loff_t *ppos)
1815{
1816 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1817 NULL,NULL);
1818}
1819
1820#define OP_SET 0
1821#define OP_AND 1
1822#define OP_OR 2
1823#define OP_MAX 3
1824#define OP_MIN 4
1825
1826static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1827 int *valp,
1828 int write, void *data)
1829{
1830 int op = *(int *)data;
1831 if (write) {
1832 int val = *negp ? -*lvalp : *lvalp;
1833 switch(op) {
1834 case OP_SET: *valp = val; break;
1835 case OP_AND: *valp &= val; break;
1836 case OP_OR: *valp |= val; break;
1837 case OP_MAX: if(*valp < val)
1838 *valp = val;
1839 break;
1840 case OP_MIN: if(*valp > val)
1841 *valp = val;
1842 break;
1843 }
1844 } else {
1845 int val = *valp;
1846 if (val < 0) {
1847 *negp = -1;
1848 *lvalp = (unsigned long)-val;
1849 } else {
1850 *negp = 0;
1851 *lvalp = (unsigned long)val;
1852 }
1853 }
1854 return 0;
1855}
1856
1857/*
1858 * init may raise the set.
1859 */
1860
1861int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1862 void __user *buffer, size_t *lenp, loff_t *ppos)
1863{
1864 int op;
1865
1866 if (!capable(CAP_SYS_MODULE)) {
1867 return -EPERM;
1868 }
1869
1870 op = (current->pid == 1) ? OP_SET : OP_AND;
1871 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1872 do_proc_dointvec_bset_conv,&op);
1873}
1874
1875struct do_proc_dointvec_minmax_conv_param {
1876 int *min;
1877 int *max;
1878};
1879
1880static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1881 int *valp,
1882 int write, void *data)
1883{
1884 struct do_proc_dointvec_minmax_conv_param *param = data;
1885 if (write) {
1886 int val = *negp ? -*lvalp : *lvalp;
1887 if ((param->min && *param->min > val) ||
1888 (param->max && *param->max < val))
1889 return -EINVAL;
1890 *valp = val;
1891 } else {
1892 int val = *valp;
1893 if (val < 0) {
1894 *negp = -1;
1895 *lvalp = (unsigned long)-val;
1896 } else {
1897 *negp = 0;
1898 *lvalp = (unsigned long)val;
1899 }
1900 }
1901 return 0;
1902}
1903
1904/**
1905 * proc_dointvec_minmax - read a vector of integers with min/max values
1906 * @table: the sysctl table
1907 * @write: %TRUE if this is a write to the sysctl file
1908 * @filp: the file structure
1909 * @buffer: the user buffer
1910 * @lenp: the size of the user buffer
1911 * @ppos: file position
1912 *
1913 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1914 * values from/to the user buffer, treated as an ASCII string.
1915 *
1916 * This routine will ensure the values are within the range specified by
1917 * table->extra1 (min) and table->extra2 (max).
1918 *
1919 * Returns 0 on success.
1920 */
1921int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1922 void __user *buffer, size_t *lenp, loff_t *ppos)
1923{
1924 struct do_proc_dointvec_minmax_conv_param param = {
1925 .min = (int *) table->extra1,
1926 .max = (int *) table->extra2,
1927 };
1928 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1929 do_proc_dointvec_minmax_conv, &param);
1930}
1931
1932static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1933 struct file *filp,
1934 void __user *buffer,
1935 size_t *lenp, loff_t *ppos,
1936 unsigned long convmul,
1937 unsigned long convdiv)
1938{
1939#define TMPBUFLEN 21
1940 unsigned long *i, *min, *max, val;
1941 int vleft, first=1, neg;
1942 size_t len, left;
1943 char buf[TMPBUFLEN], *p;
1944 char __user *s = buffer;
1945
1946 if (!table->data || !table->maxlen || !*lenp ||
1947 (*ppos && !write)) {
1948 *lenp = 0;
1949 return 0;
1950 }
1951
1952 i = (unsigned long *) table->data;
1953 min = (unsigned long *) table->extra1;
1954 max = (unsigned long *) table->extra2;
1955 vleft = table->maxlen / sizeof(unsigned long);
1956 left = *lenp;
1957
1958 for (; left && vleft--; i++, min++, max++, first=0) {
1959 if (write) {
1960 while (left) {
1961 char c;
1962 if (get_user(c, s))
1963 return -EFAULT;
1964 if (!isspace(c))
1965 break;
1966 left--;
1967 s++;
1968 }
1969 if (!left)
1970 break;
1971 neg = 0;
1972 len = left;
1973 if (len > TMPBUFLEN-1)
1974 len = TMPBUFLEN-1;
1975 if (copy_from_user(buf, s, len))
1976 return -EFAULT;
1977 buf[len] = 0;
1978 p = buf;
1979 if (*p == '-' && left > 1) {
1980 neg = 1;
1981 left--, p++;
1982 }
1983 if (*p < '0' || *p > '9')
1984 break;
1985 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1986 len = p-buf;
1987 if ((len < left) && *p && !isspace(*p))
1988 break;
1989 if (neg)
1990 val = -val;
1991 s += len;
1992 left -= len;
1993
1994 if(neg)
1995 continue;
1996 if ((min && val < *min) || (max && val > *max))
1997 continue;
1998 *i = val;
1999 } else {
2000 p = buf;
2001 if (!first)
2002 *p++ = '\t';
2003 sprintf(p, "%lu", convdiv * (*i) / convmul);
2004 len = strlen(buf);
2005 if (len > left)
2006 len = left;
2007 if(copy_to_user(s, buf, len))
2008 return -EFAULT;
2009 left -= len;
2010 s += len;
2011 }
2012 }
2013
2014 if (!write && !first && left) {
2015 if(put_user('\n', s))
2016 return -EFAULT;
2017 left--, s++;
2018 }
2019 if (write) {
2020 while (left) {
2021 char c;
2022 if (get_user(c, s++))
2023 return -EFAULT;
2024 if (!isspace(c))
2025 break;
2026 left--;
2027 }
2028 }
2029 if (write && first)
2030 return -EINVAL;
2031 *lenp -= left;
2032 *ppos += *lenp;
2033 return 0;
2034#undef TMPBUFLEN
2035}
2036
2037/**
2038 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2039 * @table: the sysctl table
2040 * @write: %TRUE if this is a write to the sysctl file
2041 * @filp: the file structure
2042 * @buffer: the user buffer
2043 * @lenp: the size of the user buffer
2044 * @ppos: file position
2045 *
2046 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2047 * values from/to the user buffer, treated as an ASCII string.
2048 *
2049 * This routine will ensure the values are within the range specified by
2050 * table->extra1 (min) and table->extra2 (max).
2051 *
2052 * Returns 0 on success.
2053 */
2054int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2055 void __user *buffer, size_t *lenp, loff_t *ppos)
2056{
2057 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2058}
2059
2060/**
2061 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2062 * @table: the sysctl table
2063 * @write: %TRUE if this is a write to the sysctl file
2064 * @filp: the file structure
2065 * @buffer: the user buffer
2066 * @lenp: the size of the user buffer
2067 * @ppos: file position
2068 *
2069 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2070 * values from/to the user buffer, treated as an ASCII string. The values
2071 * are treated as milliseconds, and converted to jiffies when they are stored.
2072 *
2073 * This routine will ensure the values are within the range specified by
2074 * table->extra1 (min) and table->extra2 (max).
2075 *
2076 * Returns 0 on success.
2077 */
2078int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2079 struct file *filp,
2080 void __user *buffer,
2081 size_t *lenp, loff_t *ppos)
2082{
2083 return do_proc_doulongvec_minmax(table, write, filp, buffer,
2084 lenp, ppos, HZ, 1000l);
2085}
2086
2087
2088static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2089 int *valp,
2090 int write, void *data)
2091{
2092 if (write) {
cba9f33d
BS
2093 if (*lvalp > LONG_MAX / HZ)
2094 return 1;
1da177e4
LT
2095 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2096 } else {
2097 int val = *valp;
2098 unsigned long lval;
2099 if (val < 0) {
2100 *negp = -1;
2101 lval = (unsigned long)-val;
2102 } else {
2103 *negp = 0;
2104 lval = (unsigned long)val;
2105 }
2106 *lvalp = lval / HZ;
2107 }
2108 return 0;
2109}
2110
2111static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2112 int *valp,
2113 int write, void *data)
2114{
2115 if (write) {
cba9f33d
BS
2116 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2117 return 1;
1da177e4
LT
2118 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2119 } else {
2120 int val = *valp;
2121 unsigned long lval;
2122 if (val < 0) {
2123 *negp = -1;
2124 lval = (unsigned long)-val;
2125 } else {
2126 *negp = 0;
2127 lval = (unsigned long)val;
2128 }
2129 *lvalp = jiffies_to_clock_t(lval);
2130 }
2131 return 0;
2132}
2133
2134static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2135 int *valp,
2136 int write, void *data)
2137{
2138 if (write) {
2139 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2140 } else {
2141 int val = *valp;
2142 unsigned long lval;
2143 if (val < 0) {
2144 *negp = -1;
2145 lval = (unsigned long)-val;
2146 } else {
2147 *negp = 0;
2148 lval = (unsigned long)val;
2149 }
2150 *lvalp = jiffies_to_msecs(lval);
2151 }
2152 return 0;
2153}
2154
2155/**
2156 * proc_dointvec_jiffies - read a vector of integers as seconds
2157 * @table: the sysctl table
2158 * @write: %TRUE if this is a write to the sysctl file
2159 * @filp: the file structure
2160 * @buffer: the user buffer
2161 * @lenp: the size of the user buffer
2162 * @ppos: file position
2163 *
2164 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2165 * values from/to the user buffer, treated as an ASCII string.
2166 * The values read are assumed to be in seconds, and are converted into
2167 * jiffies.
2168 *
2169 * Returns 0 on success.
2170 */
2171int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2172 void __user *buffer, size_t *lenp, loff_t *ppos)
2173{
2174 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2175 do_proc_dointvec_jiffies_conv,NULL);
2176}
2177
2178/**
2179 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2180 * @table: the sysctl table
2181 * @write: %TRUE if this is a write to the sysctl file
2182 * @filp: the file structure
2183 * @buffer: the user buffer
2184 * @lenp: the size of the user buffer
1e5d5331 2185 * @ppos: pointer to the file position
1da177e4
LT
2186 *
2187 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2188 * values from/to the user buffer, treated as an ASCII string.
2189 * The values read are assumed to be in 1/USER_HZ seconds, and
2190 * are converted into jiffies.
2191 *
2192 * Returns 0 on success.
2193 */
2194int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2195 void __user *buffer, size_t *lenp, loff_t *ppos)
2196{
2197 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2198 do_proc_dointvec_userhz_jiffies_conv,NULL);
2199}
2200
2201/**
2202 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2203 * @table: the sysctl table
2204 * @write: %TRUE if this is a write to the sysctl file
2205 * @filp: the file structure
2206 * @buffer: the user buffer
2207 * @lenp: the size of the user buffer
67be2dd1
MW
2208 * @ppos: file position
2209 * @ppos: the current position in the file
1da177e4
LT
2210 *
2211 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2212 * values from/to the user buffer, treated as an ASCII string.
2213 * The values read are assumed to be in 1/1000 seconds, and
2214 * are converted into jiffies.
2215 *
2216 * Returns 0 on success.
2217 */
2218int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2219 void __user *buffer, size_t *lenp, loff_t *ppos)
2220{
2221 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2222 do_proc_dointvec_ms_jiffies_conv, NULL);
2223}
2224
2225#else /* CONFIG_PROC_FS */
2226
2227int proc_dostring(ctl_table *table, int write, struct file *filp,
2228 void __user *buffer, size_t *lenp, loff_t *ppos)
2229{
2230 return -ENOSYS;
2231}
2232
2233static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
2234 void __user *buffer, size_t *lenp, loff_t *ppos)
2235{
2236 return -ENOSYS;
2237}
2238
2239int proc_dointvec(ctl_table *table, int write, struct file *filp,
2240 void __user *buffer, size_t *lenp, loff_t *ppos)
2241{
2242 return -ENOSYS;
2243}
2244
2245int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2246 void __user *buffer, size_t *lenp, loff_t *ppos)
2247{
2248 return -ENOSYS;
2249}
2250
2251int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2252 void __user *buffer, size_t *lenp, loff_t *ppos)
2253{
2254 return -ENOSYS;
2255}
2256
2257int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2258 void __user *buffer, size_t *lenp, loff_t *ppos)
2259{
2260 return -ENOSYS;
2261}
2262
2263int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2264 void __user *buffer, size_t *lenp, loff_t *ppos)
2265{
2266 return -ENOSYS;
2267}
2268
2269int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2270 void __user *buffer, size_t *lenp, loff_t *ppos)
2271{
2272 return -ENOSYS;
2273}
2274
2275int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2276 void __user *buffer, size_t *lenp, loff_t *ppos)
2277{
2278 return -ENOSYS;
2279}
2280
2281int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2282 struct file *filp,
2283 void __user *buffer,
2284 size_t *lenp, loff_t *ppos)
2285{
2286 return -ENOSYS;
2287}
2288
2289
2290#endif /* CONFIG_PROC_FS */
2291
2292
2293/*
2294 * General sysctl support routines
2295 */
2296
2297/* The generic string strategy routine: */
2298int sysctl_string(ctl_table *table, int __user *name, int nlen,
2299 void __user *oldval, size_t __user *oldlenp,
2300 void __user *newval, size_t newlen, void **context)
2301{
1da177e4
LT
2302 if (!table->data || !table->maxlen)
2303 return -ENOTDIR;
2304
2305 if (oldval && oldlenp) {
de9e007d
LT
2306 size_t bufsize;
2307 if (get_user(bufsize, oldlenp))
1da177e4 2308 return -EFAULT;
de9e007d
LT
2309 if (bufsize) {
2310 size_t len = strlen(table->data), copied;
2311
2312 /* This shouldn't trigger for a well-formed sysctl */
2313 if (len > table->maxlen)
1da177e4 2314 len = table->maxlen;
de9e007d
LT
2315
2316 /* Copy up to a max of bufsize-1 bytes of the string */
2317 copied = (len >= bufsize) ? bufsize - 1 : len;
2318
2319 if (copy_to_user(oldval, table->data, copied) ||
2320 put_user(0, (char __user *)(oldval + copied)))
1da177e4 2321 return -EFAULT;
de9e007d 2322 if (put_user(len, oldlenp))
1da177e4
LT
2323 return -EFAULT;
2324 }
2325 }
2326 if (newval && newlen) {
de9e007d 2327 size_t len = newlen;
1da177e4
LT
2328 if (len > table->maxlen)
2329 len = table->maxlen;
2330 if(copy_from_user(table->data, newval, len))
2331 return -EFAULT;
2332 if (len == table->maxlen)
2333 len--;
2334 ((char *) table->data)[len] = 0;
2335 }
82c9df82 2336 return 1;
1da177e4
LT
2337}
2338
2339/*
2340 * This function makes sure that all of the integers in the vector
2341 * are between the minimum and maximum values given in the arrays
2342 * table->extra1 and table->extra2, respectively.
2343 */
2344int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2345 void __user *oldval, size_t __user *oldlenp,
2346 void __user *newval, size_t newlen, void **context)
2347{
2348
2349 if (newval && newlen) {
2350 int __user *vec = (int __user *) newval;
2351 int *min = (int *) table->extra1;
2352 int *max = (int *) table->extra2;
2353 size_t length;
2354 int i;
2355
2356 if (newlen % sizeof(int) != 0)
2357 return -EINVAL;
2358
2359 if (!table->extra1 && !table->extra2)
2360 return 0;
2361
2362 if (newlen > table->maxlen)
2363 newlen = table->maxlen;
2364 length = newlen / sizeof(int);
2365
2366 for (i = 0; i < length; i++) {
2367 int value;
2368 if (get_user(value, vec + i))
2369 return -EFAULT;
2370 if (min && value < min[i])
2371 return -EINVAL;
2372 if (max && value > max[i])
2373 return -EINVAL;
2374 }
2375 }
2376 return 0;
2377}
2378
2379/* Strategy function to convert jiffies to seconds */
2380int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2381 void __user *oldval, size_t __user *oldlenp,
2382 void __user *newval, size_t newlen, void **context)
2383{
2384 if (oldval) {
2385 size_t olen;
2386 if (oldlenp) {
2387 if (get_user(olen, oldlenp))
2388 return -EFAULT;
2389 if (olen!=sizeof(int))
2390 return -EINVAL;
2391 }
2392 if (put_user(*(int *)(table->data)/HZ, (int __user *)oldval) ||
2393 (oldlenp && put_user(sizeof(int),oldlenp)))
2394 return -EFAULT;
2395 }
2396 if (newval && newlen) {
2397 int new;
2398 if (newlen != sizeof(int))
2399 return -EINVAL;
2400 if (get_user(new, (int __user *)newval))
2401 return -EFAULT;
2402 *(int *)(table->data) = new*HZ;
2403 }
2404 return 1;
2405}
2406
2407/* Strategy function to convert jiffies to seconds */
2408int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2409 void __user *oldval, size_t __user *oldlenp,
2410 void __user *newval, size_t newlen, void **context)
2411{
2412 if (oldval) {
2413 size_t olen;
2414 if (oldlenp) {
2415 if (get_user(olen, oldlenp))
2416 return -EFAULT;
2417 if (olen!=sizeof(int))
2418 return -EINVAL;
2419 }
2420 if (put_user(jiffies_to_msecs(*(int *)(table->data)), (int __user *)oldval) ||
2421 (oldlenp && put_user(sizeof(int),oldlenp)))
2422 return -EFAULT;
2423 }
2424 if (newval && newlen) {
2425 int new;
2426 if (newlen != sizeof(int))
2427 return -EINVAL;
2428 if (get_user(new, (int __user *)newval))
2429 return -EFAULT;
2430 *(int *)(table->data) = msecs_to_jiffies(new);
2431 }
2432 return 1;
2433}
2434
2435#else /* CONFIG_SYSCTL */
2436
2437
2438asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2439{
2440 return -ENOSYS;
2441}
2442
2443int sysctl_string(ctl_table *table, int __user *name, int nlen,
2444 void __user *oldval, size_t __user *oldlenp,
2445 void __user *newval, size_t newlen, void **context)
2446{
2447 return -ENOSYS;
2448}
2449
2450int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2451 void __user *oldval, size_t __user *oldlenp,
2452 void __user *newval, size_t newlen, void **context)
2453{
2454 return -ENOSYS;
2455}
2456
2457int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2458 void __user *oldval, size_t __user *oldlenp,
2459 void __user *newval, size_t newlen, void **context)
2460{
2461 return -ENOSYS;
2462}
2463
2464int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2465 void __user *oldval, size_t __user *oldlenp,
2466 void __user *newval, size_t newlen, void **context)
2467{
2468 return -ENOSYS;
2469}
2470
2471int proc_dostring(ctl_table *table, int write, struct file *filp,
2472 void __user *buffer, size_t *lenp, loff_t *ppos)
2473{
2474 return -ENOSYS;
2475}
2476
2477int proc_dointvec(ctl_table *table, int write, struct file *filp,
2478 void __user *buffer, size_t *lenp, loff_t *ppos)
2479{
2480 return -ENOSYS;
2481}
2482
2483int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2484 void __user *buffer, size_t *lenp, loff_t *ppos)
2485{
2486 return -ENOSYS;
2487}
2488
2489int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2490 void __user *buffer, size_t *lenp, loff_t *ppos)
2491{
2492 return -ENOSYS;
2493}
2494
2495int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2496 void __user *buffer, size_t *lenp, loff_t *ppos)
2497{
2498 return -ENOSYS;
2499}
2500
2501int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2502 void __user *buffer, size_t *lenp, loff_t *ppos)
2503{
2504 return -ENOSYS;
2505}
2506
2507int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2508 void __user *buffer, size_t *lenp, loff_t *ppos)
2509{
2510 return -ENOSYS;
2511}
2512
2513int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2514 void __user *buffer, size_t *lenp, loff_t *ppos)
2515{
2516 return -ENOSYS;
2517}
2518
2519int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2520 struct file *filp,
2521 void __user *buffer,
2522 size_t *lenp, loff_t *ppos)
2523{
2524 return -ENOSYS;
2525}
2526
2527struct ctl_table_header * register_sysctl_table(ctl_table * table,
2528 int insert_at_head)
2529{
2530 return NULL;
2531}
2532
2533void unregister_sysctl_table(struct ctl_table_header * table)
2534{
2535}
2536
2537#endif /* CONFIG_SYSCTL */
2538
2539/*
2540 * No sense putting this after each symbol definition, twice,
2541 * exception granted :-)
2542 */
2543EXPORT_SYMBOL(proc_dointvec);
2544EXPORT_SYMBOL(proc_dointvec_jiffies);
2545EXPORT_SYMBOL(proc_dointvec_minmax);
2546EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2547EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2548EXPORT_SYMBOL(proc_dostring);
2549EXPORT_SYMBOL(proc_doulongvec_minmax);
2550EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2551EXPORT_SYMBOL(register_sysctl_table);
2552EXPORT_SYMBOL(sysctl_intvec);
2553EXPORT_SYMBOL(sysctl_jiffies);
2554EXPORT_SYMBOL(sysctl_ms_jiffies);
2555EXPORT_SYMBOL(sysctl_string);
2556EXPORT_SYMBOL(unregister_sysctl_table);