58be76017fd000f3b019c0acab6d3cdeb672afda
[linux-2.6.git] / kernel / sysctl.c
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/security.h>
28 #include <linux/ctype.h>
29 #include <linux/utsname.h>
30 #include <linux/kmemcheck.h>
31 #include <linux/smp_lock.h>
32 #include <linux/fs.h>
33 #include <linux/init.h>
34 #include <linux/kernel.h>
35 #include <linux/kobject.h>
36 #include <linux/net.h>
37 #include <linux/sysrq.h>
38 #include <linux/highuid.h>
39 #include <linux/writeback.h>
40 #include <linux/hugetlb.h>
41 #include <linux/initrd.h>
42 #include <linux/key.h>
43 #include <linux/times.h>
44 #include <linux/limits.h>
45 #include <linux/dcache.h>
46 #include <linux/syscalls.h>
47 #include <linux/vmstat.h>
48 #include <linux/nfs_fs.h>
49 #include <linux/acpi.h>
50 #include <linux/reboot.h>
51 #include <linux/ftrace.h>
52 #include <linux/security.h>
53 #include <linux/slow-work.h>
54 #include <linux/perf_counter.h>
55
56 #include <asm/uaccess.h>
57 #include <asm/processor.h>
58
59 #ifdef CONFIG_X86
60 #include <asm/nmi.h>
61 #include <asm/stacktrace.h>
62 #include <asm/io.h>
63 #endif
64
65 static int deprecated_sysctl_warning(struct __sysctl_args *args);
66
67 #if defined(CONFIG_SYSCTL)
68
69 /* External variables not in a header file. */
70 extern int C_A_D;
71 extern int print_fatal_signals;
72 extern int sysctl_overcommit_memory;
73 extern int sysctl_overcommit_ratio;
74 extern int sysctl_panic_on_oom;
75 extern int sysctl_oom_kill_allocating_task;
76 extern int sysctl_oom_dump_tasks;
77 extern int max_threads;
78 extern int core_uses_pid;
79 extern int suid_dumpable;
80 extern char core_pattern[];
81 extern int pid_max;
82 extern int min_free_kbytes;
83 extern int pid_max_min, pid_max_max;
84 extern int sysctl_drop_caches;
85 extern int percpu_pagelist_fraction;
86 extern int compat_log;
87 extern int latencytop_enabled;
88 extern int sysctl_nr_open_min, sysctl_nr_open_max;
89 #ifndef CONFIG_MMU
90 extern int sysctl_nr_trim_pages;
91 #endif
92 #ifdef CONFIG_RCU_TORTURE_TEST
93 extern int rcutorture_runnable;
94 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
95
96 /* Constants used for minimum and  maximum */
97 #ifdef CONFIG_DETECT_SOFTLOCKUP
98 static int sixty = 60;
99 static int neg_one = -1;
100 #endif
101
102 static int zero;
103 static int __maybe_unused one = 1;
104 static int __maybe_unused two = 2;
105 static unsigned long one_ul = 1;
106 static int one_hundred = 100;
107
108 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
109 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
110
111 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
112 static int maxolduid = 65535;
113 static int minolduid;
114 static int min_percpu_pagelist_fract = 8;
115
116 static int ngroups_max = NGROUPS_MAX;
117
118 #ifdef CONFIG_MODULES
119 extern char modprobe_path[];
120 extern int modules_disabled;
121 #endif
122 #ifdef CONFIG_CHR_DEV_SG
123 extern int sg_big_buff;
124 #endif
125
126 #ifdef CONFIG_SPARC
127 #include <asm/system.h>
128 #endif
129
130 #ifdef CONFIG_SPARC64
131 extern int sysctl_tsb_ratio;
132 #endif
133
134 #ifdef __hppa__
135 extern int pwrsw_enabled;
136 extern int unaligned_enabled;
137 #endif
138
139 #ifdef CONFIG_S390
140 #ifdef CONFIG_MATHEMU
141 extern int sysctl_ieee_emulation_warnings;
142 #endif
143 extern int sysctl_userprocess_debug;
144 extern int spin_retry;
145 #endif
146
147 #ifdef CONFIG_BSD_PROCESS_ACCT
148 extern int acct_parm[];
149 #endif
150
151 #ifdef CONFIG_IA64
152 extern int no_unaligned_warning;
153 extern int unaligned_dump_stack;
154 #endif
155
156 #ifdef CONFIG_RT_MUTEXES
157 extern int max_lock_depth;
158 #endif
159
160 #ifdef CONFIG_PROC_SYSCTL
161 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
162                   void __user *buffer, size_t *lenp, loff_t *ppos);
163 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
164                                void __user *buffer, size_t *lenp, loff_t *ppos);
165 #endif
166
167 static struct ctl_table root_table[];
168 static struct ctl_table_root sysctl_table_root;
169 static struct ctl_table_header root_table_header = {
170         .count = 1,
171         .ctl_table = root_table,
172         .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
173         .root = &sysctl_table_root,
174         .set = &sysctl_table_root.default_set,
175 };
176 static struct ctl_table_root sysctl_table_root = {
177         .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
178         .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
179 };
180
181 static struct ctl_table kern_table[];
182 static struct ctl_table vm_table[];
183 static struct ctl_table fs_table[];
184 static struct ctl_table debug_table[];
185 static struct ctl_table dev_table[];
186 extern struct ctl_table random_table[];
187 #ifdef CONFIG_INOTIFY_USER
188 extern struct ctl_table inotify_table[];
189 #endif
190 #ifdef CONFIG_EPOLL
191 extern struct ctl_table epoll_table[];
192 #endif
193
194 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
195 int sysctl_legacy_va_layout;
196 #endif
197
198 extern int prove_locking;
199 extern int lock_stat;
200
201 /* The default sysctl tables: */
202
203 static struct ctl_table root_table[] = {
204         {
205                 .ctl_name       = CTL_KERN,
206                 .procname       = "kernel",
207                 .mode           = 0555,
208                 .child          = kern_table,
209         },
210         {
211                 .ctl_name       = CTL_VM,
212                 .procname       = "vm",
213                 .mode           = 0555,
214                 .child          = vm_table,
215         },
216         {
217                 .ctl_name       = CTL_FS,
218                 .procname       = "fs",
219                 .mode           = 0555,
220                 .child          = fs_table,
221         },
222         {
223                 .ctl_name       = CTL_DEBUG,
224                 .procname       = "debug",
225                 .mode           = 0555,
226                 .child          = debug_table,
227         },
228         {
229                 .ctl_name       = CTL_DEV,
230                 .procname       = "dev",
231                 .mode           = 0555,
232                 .child          = dev_table,
233         },
234 /*
235  * NOTE: do not add new entries to this table unless you have read
236  * Documentation/sysctl/ctl_unnumbered.txt
237  */
238         { .ctl_name = 0 }
239 };
240
241 #ifdef CONFIG_SCHED_DEBUG
242 static int min_sched_granularity_ns = 100000;           /* 100 usecs */
243 static int max_sched_granularity_ns = NSEC_PER_SEC;     /* 1 second */
244 static int min_wakeup_granularity_ns;                   /* 0 usecs */
245 static int max_wakeup_granularity_ns = NSEC_PER_SEC;    /* 1 second */
246 #endif
247
248 static struct ctl_table kern_table[] = {
249 #ifdef CONFIG_SCHED_DEBUG
250         {
251                 .ctl_name       = CTL_UNNUMBERED,
252                 .procname       = "sched_min_granularity_ns",
253                 .data           = &sysctl_sched_min_granularity,
254                 .maxlen         = sizeof(unsigned int),
255                 .mode           = 0644,
256                 .proc_handler   = &sched_nr_latency_handler,
257                 .strategy       = &sysctl_intvec,
258                 .extra1         = &min_sched_granularity_ns,
259                 .extra2         = &max_sched_granularity_ns,
260         },
261         {
262                 .ctl_name       = CTL_UNNUMBERED,
263                 .procname       = "sched_latency_ns",
264                 .data           = &sysctl_sched_latency,
265                 .maxlen         = sizeof(unsigned int),
266                 .mode           = 0644,
267                 .proc_handler   = &sched_nr_latency_handler,
268                 .strategy       = &sysctl_intvec,
269                 .extra1         = &min_sched_granularity_ns,
270                 .extra2         = &max_sched_granularity_ns,
271         },
272         {
273                 .ctl_name       = CTL_UNNUMBERED,
274                 .procname       = "sched_wakeup_granularity_ns",
275                 .data           = &sysctl_sched_wakeup_granularity,
276                 .maxlen         = sizeof(unsigned int),
277                 .mode           = 0644,
278                 .proc_handler   = &proc_dointvec_minmax,
279                 .strategy       = &sysctl_intvec,
280                 .extra1         = &min_wakeup_granularity_ns,
281                 .extra2         = &max_wakeup_granularity_ns,
282         },
283         {
284                 .ctl_name       = CTL_UNNUMBERED,
285                 .procname       = "sched_shares_ratelimit",
286                 .data           = &sysctl_sched_shares_ratelimit,
287                 .maxlen         = sizeof(unsigned int),
288                 .mode           = 0644,
289                 .proc_handler   = &proc_dointvec,
290         },
291         {
292                 .ctl_name       = CTL_UNNUMBERED,
293                 .procname       = "sched_shares_thresh",
294                 .data           = &sysctl_sched_shares_thresh,
295                 .maxlen         = sizeof(unsigned int),
296                 .mode           = 0644,
297                 .proc_handler   = &proc_dointvec_minmax,
298                 .strategy       = &sysctl_intvec,
299                 .extra1         = &zero,
300         },
301         {
302                 .ctl_name       = CTL_UNNUMBERED,
303                 .procname       = "sched_child_runs_first",
304                 .data           = &sysctl_sched_child_runs_first,
305                 .maxlen         = sizeof(unsigned int),
306                 .mode           = 0644,
307                 .proc_handler   = &proc_dointvec,
308         },
309         {
310                 .ctl_name       = CTL_UNNUMBERED,
311                 .procname       = "sched_features",
312                 .data           = &sysctl_sched_features,
313                 .maxlen         = sizeof(unsigned int),
314                 .mode           = 0644,
315                 .proc_handler   = &proc_dointvec,
316         },
317         {
318                 .ctl_name       = CTL_UNNUMBERED,
319                 .procname       = "sched_migration_cost",
320                 .data           = &sysctl_sched_migration_cost,
321                 .maxlen         = sizeof(unsigned int),
322                 .mode           = 0644,
323                 .proc_handler   = &proc_dointvec,
324         },
325         {
326                 .ctl_name       = CTL_UNNUMBERED,
327                 .procname       = "sched_nr_migrate",
328                 .data           = &sysctl_sched_nr_migrate,
329                 .maxlen         = sizeof(unsigned int),
330                 .mode           = 0644,
331                 .proc_handler   = &proc_dointvec,
332         },
333         {
334                 .ctl_name       = CTL_UNNUMBERED,
335                 .procname       = "timer_migration",
336                 .data           = &sysctl_timer_migration,
337                 .maxlen         = sizeof(unsigned int),
338                 .mode           = 0644,
339                 .proc_handler   = &proc_dointvec_minmax,
340                 .strategy       = &sysctl_intvec,
341                 .extra1         = &zero,
342                 .extra2         = &one,
343         },
344 #endif
345         {
346                 .ctl_name       = CTL_UNNUMBERED,
347                 .procname       = "sched_rt_period_us",
348                 .data           = &sysctl_sched_rt_period,
349                 .maxlen         = sizeof(unsigned int),
350                 .mode           = 0644,
351                 .proc_handler   = &sched_rt_handler,
352         },
353         {
354                 .ctl_name       = CTL_UNNUMBERED,
355                 .procname       = "sched_rt_runtime_us",
356                 .data           = &sysctl_sched_rt_runtime,
357                 .maxlen         = sizeof(int),
358                 .mode           = 0644,
359                 .proc_handler   = &sched_rt_handler,
360         },
361         {
362                 .ctl_name       = CTL_UNNUMBERED,
363                 .procname       = "sched_compat_yield",
364                 .data           = &sysctl_sched_compat_yield,
365                 .maxlen         = sizeof(unsigned int),
366                 .mode           = 0644,
367                 .proc_handler   = &proc_dointvec,
368         },
369 #ifdef CONFIG_PROVE_LOCKING
370         {
371                 .ctl_name       = CTL_UNNUMBERED,
372                 .procname       = "prove_locking",
373                 .data           = &prove_locking,
374                 .maxlen         = sizeof(int),
375                 .mode           = 0644,
376                 .proc_handler   = &proc_dointvec,
377         },
378 #endif
379 #ifdef CONFIG_LOCK_STAT
380         {
381                 .ctl_name       = CTL_UNNUMBERED,
382                 .procname       = "lock_stat",
383                 .data           = &lock_stat,
384                 .maxlen         = sizeof(int),
385                 .mode           = 0644,
386                 .proc_handler   = &proc_dointvec,
387         },
388 #endif
389         {
390                 .ctl_name       = KERN_PANIC,
391                 .procname       = "panic",
392                 .data           = &panic_timeout,
393                 .maxlen         = sizeof(int),
394                 .mode           = 0644,
395                 .proc_handler   = &proc_dointvec,
396         },
397         {
398                 .ctl_name       = KERN_CORE_USES_PID,
399                 .procname       = "core_uses_pid",
400                 .data           = &core_uses_pid,
401                 .maxlen         = sizeof(int),
402                 .mode           = 0644,
403                 .proc_handler   = &proc_dointvec,
404         },
405         {
406                 .ctl_name       = KERN_CORE_PATTERN,
407                 .procname       = "core_pattern",
408                 .data           = core_pattern,
409                 .maxlen         = CORENAME_MAX_SIZE,
410                 .mode           = 0644,
411                 .proc_handler   = &proc_dostring,
412                 .strategy       = &sysctl_string,
413         },
414 #ifdef CONFIG_PROC_SYSCTL
415         {
416                 .procname       = "tainted",
417                 .maxlen         = sizeof(long),
418                 .mode           = 0644,
419                 .proc_handler   = &proc_taint,
420         },
421 #endif
422 #ifdef CONFIG_LATENCYTOP
423         {
424                 .procname       = "latencytop",
425                 .data           = &latencytop_enabled,
426                 .maxlen         = sizeof(int),
427                 .mode           = 0644,
428                 .proc_handler   = &proc_dointvec,
429         },
430 #endif
431 #ifdef CONFIG_BLK_DEV_INITRD
432         {
433                 .ctl_name       = KERN_REALROOTDEV,
434                 .procname       = "real-root-dev",
435                 .data           = &real_root_dev,
436                 .maxlen         = sizeof(int),
437                 .mode           = 0644,
438                 .proc_handler   = &proc_dointvec,
439         },
440 #endif
441         {
442                 .ctl_name       = CTL_UNNUMBERED,
443                 .procname       = "print-fatal-signals",
444                 .data           = &print_fatal_signals,
445                 .maxlen         = sizeof(int),
446                 .mode           = 0644,
447                 .proc_handler   = &proc_dointvec,
448         },
449 #ifdef CONFIG_SPARC
450         {
451                 .ctl_name       = KERN_SPARC_REBOOT,
452                 .procname       = "reboot-cmd",
453                 .data           = reboot_command,
454                 .maxlen         = 256,
455                 .mode           = 0644,
456                 .proc_handler   = &proc_dostring,
457                 .strategy       = &sysctl_string,
458         },
459         {
460                 .ctl_name       = KERN_SPARC_STOP_A,
461                 .procname       = "stop-a",
462                 .data           = &stop_a_enabled,
463                 .maxlen         = sizeof (int),
464                 .mode           = 0644,
465                 .proc_handler   = &proc_dointvec,
466         },
467         {
468                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
469                 .procname       = "scons-poweroff",
470                 .data           = &scons_pwroff,
471                 .maxlen         = sizeof (int),
472                 .mode           = 0644,
473                 .proc_handler   = &proc_dointvec,
474         },
475 #endif
476 #ifdef CONFIG_SPARC64
477         {
478                 .ctl_name       = CTL_UNNUMBERED,
479                 .procname       = "tsb-ratio",
480                 .data           = &sysctl_tsb_ratio,
481                 .maxlen         = sizeof (int),
482                 .mode           = 0644,
483                 .proc_handler   = &proc_dointvec,
484         },
485 #endif
486 #ifdef __hppa__
487         {
488                 .ctl_name       = KERN_HPPA_PWRSW,
489                 .procname       = "soft-power",
490                 .data           = &pwrsw_enabled,
491                 .maxlen         = sizeof (int),
492                 .mode           = 0644,
493                 .proc_handler   = &proc_dointvec,
494         },
495         {
496                 .ctl_name       = KERN_HPPA_UNALIGNED,
497                 .procname       = "unaligned-trap",
498                 .data           = &unaligned_enabled,
499                 .maxlen         = sizeof (int),
500                 .mode           = 0644,
501                 .proc_handler   = &proc_dointvec,
502         },
503 #endif
504         {
505                 .ctl_name       = KERN_CTLALTDEL,
506                 .procname       = "ctrl-alt-del",
507                 .data           = &C_A_D,
508                 .maxlen         = sizeof(int),
509                 .mode           = 0644,
510                 .proc_handler   = &proc_dointvec,
511         },
512 #ifdef CONFIG_FUNCTION_TRACER
513         {
514                 .ctl_name       = CTL_UNNUMBERED,
515                 .procname       = "ftrace_enabled",
516                 .data           = &ftrace_enabled,
517                 .maxlen         = sizeof(int),
518                 .mode           = 0644,
519                 .proc_handler   = &ftrace_enable_sysctl,
520         },
521 #endif
522 #ifdef CONFIG_STACK_TRACER
523         {
524                 .ctl_name       = CTL_UNNUMBERED,
525                 .procname       = "stack_tracer_enabled",
526                 .data           = &stack_tracer_enabled,
527                 .maxlen         = sizeof(int),
528                 .mode           = 0644,
529                 .proc_handler   = &stack_trace_sysctl,
530         },
531 #endif
532 #ifdef CONFIG_TRACING
533         {
534                 .ctl_name       = CTL_UNNUMBERED,
535                 .procname       = "ftrace_dump_on_oops",
536                 .data           = &ftrace_dump_on_oops,
537                 .maxlen         = sizeof(int),
538                 .mode           = 0644,
539                 .proc_handler   = &proc_dointvec,
540         },
541 #endif
542 #ifdef CONFIG_MODULES
543         {
544                 .ctl_name       = KERN_MODPROBE,
545                 .procname       = "modprobe",
546                 .data           = &modprobe_path,
547                 .maxlen         = KMOD_PATH_LEN,
548                 .mode           = 0644,
549                 .proc_handler   = &proc_dostring,
550                 .strategy       = &sysctl_string,
551         },
552         {
553                 .ctl_name       = CTL_UNNUMBERED,
554                 .procname       = "modules_disabled",
555                 .data           = &modules_disabled,
556                 .maxlen         = sizeof(int),
557                 .mode           = 0644,
558                 /* only handle a transition from default "0" to "1" */
559                 .proc_handler   = &proc_dointvec_minmax,
560                 .extra1         = &one,
561                 .extra2         = &one,
562         },
563 #endif
564 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
565         {
566                 .ctl_name       = KERN_HOTPLUG,
567                 .procname       = "hotplug",
568                 .data           = &uevent_helper,
569                 .maxlen         = UEVENT_HELPER_PATH_LEN,
570                 .mode           = 0644,
571                 .proc_handler   = &proc_dostring,
572                 .strategy       = &sysctl_string,
573         },
574 #endif
575 #ifdef CONFIG_CHR_DEV_SG
576         {
577                 .ctl_name       = KERN_SG_BIG_BUFF,
578                 .procname       = "sg-big-buff",
579                 .data           = &sg_big_buff,
580                 .maxlen         = sizeof (int),
581                 .mode           = 0444,
582                 .proc_handler   = &proc_dointvec,
583         },
584 #endif
585 #ifdef CONFIG_BSD_PROCESS_ACCT
586         {
587                 .ctl_name       = KERN_ACCT,
588                 .procname       = "acct",
589                 .data           = &acct_parm,
590                 .maxlen         = 3*sizeof(int),
591                 .mode           = 0644,
592                 .proc_handler   = &proc_dointvec,
593         },
594 #endif
595 #ifdef CONFIG_MAGIC_SYSRQ
596         {
597                 .ctl_name       = KERN_SYSRQ,
598                 .procname       = "sysrq",
599                 .data           = &__sysrq_enabled,
600                 .maxlen         = sizeof (int),
601                 .mode           = 0644,
602                 .proc_handler   = &proc_dointvec,
603         },
604 #endif
605 #ifdef CONFIG_PROC_SYSCTL
606         {
607                 .procname       = "cad_pid",
608                 .data           = NULL,
609                 .maxlen         = sizeof (int),
610                 .mode           = 0600,
611                 .proc_handler   = &proc_do_cad_pid,
612         },
613 #endif
614         {
615                 .ctl_name       = KERN_MAX_THREADS,
616                 .procname       = "threads-max",
617                 .data           = &max_threads,
618                 .maxlen         = sizeof(int),
619                 .mode           = 0644,
620                 .proc_handler   = &proc_dointvec,
621         },
622         {
623                 .ctl_name       = KERN_RANDOM,
624                 .procname       = "random",
625                 .mode           = 0555,
626                 .child          = random_table,
627         },
628         {
629                 .ctl_name       = KERN_OVERFLOWUID,
630                 .procname       = "overflowuid",
631                 .data           = &overflowuid,
632                 .maxlen         = sizeof(int),
633                 .mode           = 0644,
634                 .proc_handler   = &proc_dointvec_minmax,
635                 .strategy       = &sysctl_intvec,
636                 .extra1         = &minolduid,
637                 .extra2         = &maxolduid,
638         },
639         {
640                 .ctl_name       = KERN_OVERFLOWGID,
641                 .procname       = "overflowgid",
642                 .data           = &overflowgid,
643                 .maxlen         = sizeof(int),
644                 .mode           = 0644,
645                 .proc_handler   = &proc_dointvec_minmax,
646                 .strategy       = &sysctl_intvec,
647                 .extra1         = &minolduid,
648                 .extra2         = &maxolduid,
649         },
650 #ifdef CONFIG_S390
651 #ifdef CONFIG_MATHEMU
652         {
653                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
654                 .procname       = "ieee_emulation_warnings",
655                 .data           = &sysctl_ieee_emulation_warnings,
656                 .maxlen         = sizeof(int),
657                 .mode           = 0644,
658                 .proc_handler   = &proc_dointvec,
659         },
660 #endif
661         {
662                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
663                 .procname       = "userprocess_debug",
664                 .data           = &sysctl_userprocess_debug,
665                 .maxlen         = sizeof(int),
666                 .mode           = 0644,
667                 .proc_handler   = &proc_dointvec,
668         },
669 #endif
670         {
671                 .ctl_name       = KERN_PIDMAX,
672                 .procname       = "pid_max",
673                 .data           = &pid_max,
674                 .maxlen         = sizeof (int),
675                 .mode           = 0644,
676                 .proc_handler   = &proc_dointvec_minmax,
677                 .strategy       = sysctl_intvec,
678                 .extra1         = &pid_max_min,
679                 .extra2         = &pid_max_max,
680         },
681         {
682                 .ctl_name       = KERN_PANIC_ON_OOPS,
683                 .procname       = "panic_on_oops",
684                 .data           = &panic_on_oops,
685                 .maxlen         = sizeof(int),
686                 .mode           = 0644,
687                 .proc_handler   = &proc_dointvec,
688         },
689 #if defined CONFIG_PRINTK
690         {
691                 .ctl_name       = KERN_PRINTK,
692                 .procname       = "printk",
693                 .data           = &console_loglevel,
694                 .maxlen         = 4*sizeof(int),
695                 .mode           = 0644,
696                 .proc_handler   = &proc_dointvec,
697         },
698         {
699                 .ctl_name       = KERN_PRINTK_RATELIMIT,
700                 .procname       = "printk_ratelimit",
701                 .data           = &printk_ratelimit_state.interval,
702                 .maxlen         = sizeof(int),
703                 .mode           = 0644,
704                 .proc_handler   = &proc_dointvec_jiffies,
705                 .strategy       = &sysctl_jiffies,
706         },
707         {
708                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
709                 .procname       = "printk_ratelimit_burst",
710                 .data           = &printk_ratelimit_state.burst,
711                 .maxlen         = sizeof(int),
712                 .mode           = 0644,
713                 .proc_handler   = &proc_dointvec,
714         },
715 #endif
716         {
717                 .ctl_name       = KERN_NGROUPS_MAX,
718                 .procname       = "ngroups_max",
719                 .data           = &ngroups_max,
720                 .maxlen         = sizeof (int),
721                 .mode           = 0444,
722                 .proc_handler   = &proc_dointvec,
723         },
724 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
725         {
726                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
727                 .procname       = "unknown_nmi_panic",
728                 .data           = &unknown_nmi_panic,
729                 .maxlen         = sizeof (int),
730                 .mode           = 0644,
731                 .proc_handler   = &proc_dointvec,
732         },
733         {
734                 .procname       = "nmi_watchdog",
735                 .data           = &nmi_watchdog_enabled,
736                 .maxlen         = sizeof (int),
737                 .mode           = 0644,
738                 .proc_handler   = &proc_nmi_enabled,
739         },
740 #endif
741 #if defined(CONFIG_X86)
742         {
743                 .ctl_name       = KERN_PANIC_ON_NMI,
744                 .procname       = "panic_on_unrecovered_nmi",
745                 .data           = &panic_on_unrecovered_nmi,
746                 .maxlen         = sizeof(int),
747                 .mode           = 0644,
748                 .proc_handler   = &proc_dointvec,
749         },
750         {
751                 .ctl_name       = CTL_UNNUMBERED,
752                 .procname       = "panic_on_io_nmi",
753                 .data           = &panic_on_io_nmi,
754                 .maxlen         = sizeof(int),
755                 .mode           = 0644,
756                 .proc_handler   = &proc_dointvec,
757         },
758         {
759                 .ctl_name       = KERN_BOOTLOADER_TYPE,
760                 .procname       = "bootloader_type",
761                 .data           = &bootloader_type,
762                 .maxlen         = sizeof (int),
763                 .mode           = 0444,
764                 .proc_handler   = &proc_dointvec,
765         },
766         {
767                 .ctl_name       = CTL_UNNUMBERED,
768                 .procname       = "bootloader_version",
769                 .data           = &bootloader_version,
770                 .maxlen         = sizeof (int),
771                 .mode           = 0444,
772                 .proc_handler   = &proc_dointvec,
773         },
774         {
775                 .ctl_name       = CTL_UNNUMBERED,
776                 .procname       = "kstack_depth_to_print",
777                 .data           = &kstack_depth_to_print,
778                 .maxlen         = sizeof(int),
779                 .mode           = 0644,
780                 .proc_handler   = &proc_dointvec,
781         },
782         {
783                 .ctl_name       = CTL_UNNUMBERED,
784                 .procname       = "io_delay_type",
785                 .data           = &io_delay_type,
786                 .maxlen         = sizeof(int),
787                 .mode           = 0644,
788                 .proc_handler   = &proc_dointvec,
789         },
790 #endif
791 #if defined(CONFIG_MMU)
792         {
793                 .ctl_name       = KERN_RANDOMIZE,
794                 .procname       = "randomize_va_space",
795                 .data           = &randomize_va_space,
796                 .maxlen         = sizeof(int),
797                 .mode           = 0644,
798                 .proc_handler   = &proc_dointvec,
799         },
800 #endif
801 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
802         {
803                 .ctl_name       = KERN_SPIN_RETRY,
804                 .procname       = "spin_retry",
805                 .data           = &spin_retry,
806                 .maxlen         = sizeof (int),
807                 .mode           = 0644,
808                 .proc_handler   = &proc_dointvec,
809         },
810 #endif
811 #if     defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
812         {
813                 .procname       = "acpi_video_flags",
814                 .data           = &acpi_realmode_flags,
815                 .maxlen         = sizeof (unsigned long),
816                 .mode           = 0644,
817                 .proc_handler   = &proc_doulongvec_minmax,
818         },
819 #endif
820 #ifdef CONFIG_IA64
821         {
822                 .ctl_name       = KERN_IA64_UNALIGNED,
823                 .procname       = "ignore-unaligned-usertrap",
824                 .data           = &no_unaligned_warning,
825                 .maxlen         = sizeof (int),
826                 .mode           = 0644,
827                 .proc_handler   = &proc_dointvec,
828         },
829         {
830                 .ctl_name       = CTL_UNNUMBERED,
831                 .procname       = "unaligned-dump-stack",
832                 .data           = &unaligned_dump_stack,
833                 .maxlen         = sizeof (int),
834                 .mode           = 0644,
835                 .proc_handler   = &proc_dointvec,
836         },
837 #endif
838 #ifdef CONFIG_DETECT_SOFTLOCKUP
839         {
840                 .ctl_name       = CTL_UNNUMBERED,
841                 .procname       = "softlockup_panic",
842                 .data           = &softlockup_panic,
843                 .maxlen         = sizeof(int),
844                 .mode           = 0644,
845                 .proc_handler   = &proc_dointvec_minmax,
846                 .strategy       = &sysctl_intvec,
847                 .extra1         = &zero,
848                 .extra2         = &one,
849         },
850         {
851                 .ctl_name       = CTL_UNNUMBERED,
852                 .procname       = "softlockup_thresh",
853                 .data           = &softlockup_thresh,
854                 .maxlen         = sizeof(int),
855                 .mode           = 0644,
856                 .proc_handler   = &proc_dosoftlockup_thresh,
857                 .strategy       = &sysctl_intvec,
858                 .extra1         = &neg_one,
859                 .extra2         = &sixty,
860         },
861 #endif
862 #ifdef CONFIG_DETECT_HUNG_TASK
863         {
864                 .ctl_name       = CTL_UNNUMBERED,
865                 .procname       = "hung_task_panic",
866                 .data           = &sysctl_hung_task_panic,
867                 .maxlen         = sizeof(int),
868                 .mode           = 0644,
869                 .proc_handler   = &proc_dointvec_minmax,
870                 .strategy       = &sysctl_intvec,
871                 .extra1         = &zero,
872                 .extra2         = &one,
873         },
874         {
875                 .ctl_name       = CTL_UNNUMBERED,
876                 .procname       = "hung_task_check_count",
877                 .data           = &sysctl_hung_task_check_count,
878                 .maxlen         = sizeof(unsigned long),
879                 .mode           = 0644,
880                 .proc_handler   = &proc_doulongvec_minmax,
881                 .strategy       = &sysctl_intvec,
882         },
883         {
884                 .ctl_name       = CTL_UNNUMBERED,
885                 .procname       = "hung_task_timeout_secs",
886                 .data           = &sysctl_hung_task_timeout_secs,
887                 .maxlen         = sizeof(unsigned long),
888                 .mode           = 0644,
889                 .proc_handler   = &proc_dohung_task_timeout_secs,
890                 .strategy       = &sysctl_intvec,
891         },
892         {
893                 .ctl_name       = CTL_UNNUMBERED,
894                 .procname       = "hung_task_warnings",
895                 .data           = &sysctl_hung_task_warnings,
896                 .maxlen         = sizeof(unsigned long),
897                 .mode           = 0644,
898                 .proc_handler   = &proc_doulongvec_minmax,
899                 .strategy       = &sysctl_intvec,
900         },
901 #endif
902 #ifdef CONFIG_COMPAT
903         {
904                 .ctl_name       = KERN_COMPAT_LOG,
905                 .procname       = "compat-log",
906                 .data           = &compat_log,
907                 .maxlen         = sizeof (int),
908                 .mode           = 0644,
909                 .proc_handler   = &proc_dointvec,
910         },
911 #endif
912 #ifdef CONFIG_RT_MUTEXES
913         {
914                 .ctl_name       = KERN_MAX_LOCK_DEPTH,
915                 .procname       = "max_lock_depth",
916                 .data           = &max_lock_depth,
917                 .maxlen         = sizeof(int),
918                 .mode           = 0644,
919                 .proc_handler   = &proc_dointvec,
920         },
921 #endif
922         {
923                 .ctl_name       = CTL_UNNUMBERED,
924                 .procname       = "poweroff_cmd",
925                 .data           = &poweroff_cmd,
926                 .maxlen         = POWEROFF_CMD_PATH_LEN,
927                 .mode           = 0644,
928                 .proc_handler   = &proc_dostring,
929                 .strategy       = &sysctl_string,
930         },
931 #ifdef CONFIG_KEYS
932         {
933                 .ctl_name       = CTL_UNNUMBERED,
934                 .procname       = "keys",
935                 .mode           = 0555,
936                 .child          = key_sysctls,
937         },
938 #endif
939 #ifdef CONFIG_RCU_TORTURE_TEST
940         {
941                 .ctl_name       = CTL_UNNUMBERED,
942                 .procname       = "rcutorture_runnable",
943                 .data           = &rcutorture_runnable,
944                 .maxlen         = sizeof(int),
945                 .mode           = 0644,
946                 .proc_handler   = &proc_dointvec,
947         },
948 #endif
949 #ifdef CONFIG_SLOW_WORK
950         {
951                 .ctl_name       = CTL_UNNUMBERED,
952                 .procname       = "slow-work",
953                 .mode           = 0555,
954                 .child          = slow_work_sysctls,
955         },
956 #endif
957 #ifdef CONFIG_PERF_COUNTERS
958         {
959                 .ctl_name       = CTL_UNNUMBERED,
960                 .procname       = "perf_counter_paranoid",
961                 .data           = &sysctl_perf_counter_paranoid,
962                 .maxlen         = sizeof(sysctl_perf_counter_paranoid),
963                 .mode           = 0644,
964                 .proc_handler   = &proc_dointvec,
965         },
966         {
967                 .ctl_name       = CTL_UNNUMBERED,
968                 .procname       = "perf_counter_mlock_kb",
969                 .data           = &sysctl_perf_counter_mlock,
970                 .maxlen         = sizeof(sysctl_perf_counter_mlock),
971                 .mode           = 0644,
972                 .proc_handler   = &proc_dointvec,
973         },
974         {
975                 .ctl_name       = CTL_UNNUMBERED,
976                 .procname       = "perf_counter_max_sample_rate",
977                 .data           = &sysctl_perf_counter_sample_rate,
978                 .maxlen         = sizeof(sysctl_perf_counter_sample_rate),
979                 .mode           = 0644,
980                 .proc_handler   = &proc_dointvec,
981         },
982 #endif
983 #ifdef CONFIG_KMEMCHECK
984         {
985                 .ctl_name       = CTL_UNNUMBERED,
986                 .procname       = "kmemcheck",
987                 .data           = &kmemcheck_enabled,
988                 .maxlen         = sizeof(int),
989                 .mode           = 0644,
990                 .proc_handler   = &proc_dointvec,
991         },
992 #endif
993
994 /*
995  * NOTE: do not add new entries to this table unless you have read
996  * Documentation/sysctl/ctl_unnumbered.txt
997  */
998         { .ctl_name = 0 }
999 };
1000
1001 static struct ctl_table vm_table[] = {
1002         {
1003                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
1004                 .procname       = "overcommit_memory",
1005                 .data           = &sysctl_overcommit_memory,
1006                 .maxlen         = sizeof(sysctl_overcommit_memory),
1007                 .mode           = 0644,
1008                 .proc_handler   = &proc_dointvec,
1009         },
1010         {
1011                 .ctl_name       = VM_PANIC_ON_OOM,
1012                 .procname       = "panic_on_oom",
1013                 .data           = &sysctl_panic_on_oom,
1014                 .maxlen         = sizeof(sysctl_panic_on_oom),
1015                 .mode           = 0644,
1016                 .proc_handler   = &proc_dointvec,
1017         },
1018         {
1019                 .ctl_name       = CTL_UNNUMBERED,
1020                 .procname       = "oom_kill_allocating_task",
1021                 .data           = &sysctl_oom_kill_allocating_task,
1022                 .maxlen         = sizeof(sysctl_oom_kill_allocating_task),
1023                 .mode           = 0644,
1024                 .proc_handler   = &proc_dointvec,
1025         },
1026         {
1027                 .ctl_name       = CTL_UNNUMBERED,
1028                 .procname       = "oom_dump_tasks",
1029                 .data           = &sysctl_oom_dump_tasks,
1030                 .maxlen         = sizeof(sysctl_oom_dump_tasks),
1031                 .mode           = 0644,
1032                 .proc_handler   = &proc_dointvec,
1033         },
1034         {
1035                 .ctl_name       = VM_OVERCOMMIT_RATIO,
1036                 .procname       = "overcommit_ratio",
1037                 .data           = &sysctl_overcommit_ratio,
1038                 .maxlen         = sizeof(sysctl_overcommit_ratio),
1039                 .mode           = 0644,
1040                 .proc_handler   = &proc_dointvec,
1041         },
1042         {
1043                 .ctl_name       = VM_PAGE_CLUSTER,
1044                 .procname       = "page-cluster", 
1045                 .data           = &page_cluster,
1046                 .maxlen         = sizeof(int),
1047                 .mode           = 0644,
1048                 .proc_handler   = &proc_dointvec,
1049         },
1050         {
1051                 .ctl_name       = VM_DIRTY_BACKGROUND,
1052                 .procname       = "dirty_background_ratio",
1053                 .data           = &dirty_background_ratio,
1054                 .maxlen         = sizeof(dirty_background_ratio),
1055                 .mode           = 0644,
1056                 .proc_handler   = &dirty_background_ratio_handler,
1057                 .strategy       = &sysctl_intvec,
1058                 .extra1         = &zero,
1059                 .extra2         = &one_hundred,
1060         },
1061         {
1062                 .ctl_name       = CTL_UNNUMBERED,
1063                 .procname       = "dirty_background_bytes",
1064                 .data           = &dirty_background_bytes,
1065                 .maxlen         = sizeof(dirty_background_bytes),
1066                 .mode           = 0644,
1067                 .proc_handler   = &dirty_background_bytes_handler,
1068                 .strategy       = &sysctl_intvec,
1069                 .extra1         = &one_ul,
1070         },
1071         {
1072                 .ctl_name       = VM_DIRTY_RATIO,
1073                 .procname       = "dirty_ratio",
1074                 .data           = &vm_dirty_ratio,
1075                 .maxlen         = sizeof(vm_dirty_ratio),
1076                 .mode           = 0644,
1077                 .proc_handler   = &dirty_ratio_handler,
1078                 .strategy       = &sysctl_intvec,
1079                 .extra1         = &zero,
1080                 .extra2         = &one_hundred,
1081         },
1082         {
1083                 .ctl_name       = CTL_UNNUMBERED,
1084                 .procname       = "dirty_bytes",
1085                 .data           = &vm_dirty_bytes,
1086                 .maxlen         = sizeof(vm_dirty_bytes),
1087                 .mode           = 0644,
1088                 .proc_handler   = &dirty_bytes_handler,
1089                 .strategy       = &sysctl_intvec,
1090                 .extra1         = &dirty_bytes_min,
1091         },
1092         {
1093                 .procname       = "dirty_writeback_centisecs",
1094                 .data           = &dirty_writeback_interval,
1095                 .maxlen         = sizeof(dirty_writeback_interval),
1096                 .mode           = 0644,
1097                 .proc_handler   = &dirty_writeback_centisecs_handler,
1098         },
1099         {
1100                 .procname       = "dirty_expire_centisecs",
1101                 .data           = &dirty_expire_interval,
1102                 .maxlen         = sizeof(dirty_expire_interval),
1103                 .mode           = 0644,
1104                 .proc_handler   = &proc_dointvec,
1105         },
1106         {
1107                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
1108                 .procname       = "nr_pdflush_threads",
1109                 .data           = &nr_pdflush_threads,
1110                 .maxlen         = sizeof nr_pdflush_threads,
1111                 .mode           = 0444 /* read-only*/,
1112                 .proc_handler   = &proc_dointvec,
1113         },
1114         {
1115                 .ctl_name       = VM_SWAPPINESS,
1116                 .procname       = "swappiness",
1117                 .data           = &vm_swappiness,
1118                 .maxlen         = sizeof(vm_swappiness),
1119                 .mode           = 0644,
1120                 .proc_handler   = &proc_dointvec_minmax,
1121                 .strategy       = &sysctl_intvec,
1122                 .extra1         = &zero,
1123                 .extra2         = &one_hundred,
1124         },
1125 #ifdef CONFIG_HUGETLB_PAGE
1126          {
1127                 .procname       = "nr_hugepages",
1128                 .data           = NULL,
1129                 .maxlen         = sizeof(unsigned long),
1130                 .mode           = 0644,
1131                 .proc_handler   = &hugetlb_sysctl_handler,
1132                 .extra1         = (void *)&hugetlb_zero,
1133                 .extra2         = (void *)&hugetlb_infinity,
1134          },
1135          {
1136                 .ctl_name       = VM_HUGETLB_GROUP,
1137                 .procname       = "hugetlb_shm_group",
1138                 .data           = &sysctl_hugetlb_shm_group,
1139                 .maxlen         = sizeof(gid_t),
1140                 .mode           = 0644,
1141                 .proc_handler   = &proc_dointvec,
1142          },
1143          {
1144                 .ctl_name       = CTL_UNNUMBERED,
1145                 .procname       = "hugepages_treat_as_movable",
1146                 .data           = &hugepages_treat_as_movable,
1147                 .maxlen         = sizeof(int),
1148                 .mode           = 0644,
1149                 .proc_handler   = &hugetlb_treat_movable_handler,
1150         },
1151         {
1152                 .ctl_name       = CTL_UNNUMBERED,
1153                 .procname       = "nr_overcommit_hugepages",
1154                 .data           = NULL,
1155                 .maxlen         = sizeof(unsigned long),
1156                 .mode           = 0644,
1157                 .proc_handler   = &hugetlb_overcommit_handler,
1158                 .extra1         = (void *)&hugetlb_zero,
1159                 .extra2         = (void *)&hugetlb_infinity,
1160         },
1161 #endif
1162         {
1163                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
1164                 .procname       = "lowmem_reserve_ratio",
1165                 .data           = &sysctl_lowmem_reserve_ratio,
1166                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
1167                 .mode           = 0644,
1168                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
1169                 .strategy       = &sysctl_intvec,
1170         },
1171         {
1172                 .ctl_name       = VM_DROP_PAGECACHE,
1173                 .procname       = "drop_caches",
1174                 .data           = &sysctl_drop_caches,
1175                 .maxlen         = sizeof(int),
1176                 .mode           = 0644,
1177                 .proc_handler   = drop_caches_sysctl_handler,
1178                 .strategy       = &sysctl_intvec,
1179         },
1180         {
1181                 .ctl_name       = VM_MIN_FREE_KBYTES,
1182                 .procname       = "min_free_kbytes",
1183                 .data           = &min_free_kbytes,
1184                 .maxlen         = sizeof(min_free_kbytes),
1185                 .mode           = 0644,
1186                 .proc_handler   = &min_free_kbytes_sysctl_handler,
1187                 .strategy       = &sysctl_intvec,
1188                 .extra1         = &zero,
1189         },
1190         {
1191                 .ctl_name       = VM_PERCPU_PAGELIST_FRACTION,
1192                 .procname       = "percpu_pagelist_fraction",
1193                 .data           = &percpu_pagelist_fraction,
1194                 .maxlen         = sizeof(percpu_pagelist_fraction),
1195                 .mode           = 0644,
1196                 .proc_handler   = &percpu_pagelist_fraction_sysctl_handler,
1197                 .strategy       = &sysctl_intvec,
1198                 .extra1         = &min_percpu_pagelist_fract,
1199         },
1200 #ifdef CONFIG_MMU
1201         {
1202                 .ctl_name       = VM_MAX_MAP_COUNT,
1203                 .procname       = "max_map_count",
1204                 .data           = &sysctl_max_map_count,
1205                 .maxlen         = sizeof(sysctl_max_map_count),
1206                 .mode           = 0644,
1207                 .proc_handler   = &proc_dointvec
1208         },
1209 #else
1210         {
1211                 .ctl_name       = CTL_UNNUMBERED,
1212                 .procname       = "nr_trim_pages",
1213                 .data           = &sysctl_nr_trim_pages,
1214                 .maxlen         = sizeof(sysctl_nr_trim_pages),
1215                 .mode           = 0644,
1216                 .proc_handler   = &proc_dointvec_minmax,
1217                 .strategy       = &sysctl_intvec,
1218                 .extra1         = &zero,
1219         },
1220 #endif
1221         {
1222                 .ctl_name       = VM_LAPTOP_MODE,
1223                 .procname       = "laptop_mode",
1224                 .data           = &laptop_mode,
1225                 .maxlen         = sizeof(laptop_mode),
1226                 .mode           = 0644,
1227                 .proc_handler   = &proc_dointvec_jiffies,
1228                 .strategy       = &sysctl_jiffies,
1229         },
1230         {
1231                 .ctl_name       = VM_BLOCK_DUMP,
1232                 .procname       = "block_dump",
1233                 .data           = &block_dump,
1234                 .maxlen         = sizeof(block_dump),
1235                 .mode           = 0644,
1236                 .proc_handler   = &proc_dointvec,
1237                 .strategy       = &sysctl_intvec,
1238                 .extra1         = &zero,
1239         },
1240         {
1241                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
1242                 .procname       = "vfs_cache_pressure",
1243                 .data           = &sysctl_vfs_cache_pressure,
1244                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
1245                 .mode           = 0644,
1246                 .proc_handler   = &proc_dointvec,
1247                 .strategy       = &sysctl_intvec,
1248                 .extra1         = &zero,
1249         },
1250 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1251         {
1252                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
1253                 .procname       = "legacy_va_layout",
1254                 .data           = &sysctl_legacy_va_layout,
1255                 .maxlen         = sizeof(sysctl_legacy_va_layout),
1256                 .mode           = 0644,
1257                 .proc_handler   = &proc_dointvec,
1258                 .strategy       = &sysctl_intvec,
1259                 .extra1         = &zero,
1260         },
1261 #endif
1262 #ifdef CONFIG_NUMA
1263         {
1264                 .ctl_name       = VM_ZONE_RECLAIM_MODE,
1265                 .procname       = "zone_reclaim_mode",
1266                 .data           = &zone_reclaim_mode,
1267                 .maxlen         = sizeof(zone_reclaim_mode),
1268                 .mode           = 0644,
1269                 .proc_handler   = &proc_dointvec,
1270                 .strategy       = &sysctl_intvec,
1271                 .extra1         = &zero,
1272         },
1273         {
1274                 .ctl_name       = VM_MIN_UNMAPPED,
1275                 .procname       = "min_unmapped_ratio",
1276                 .data           = &sysctl_min_unmapped_ratio,
1277                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
1278                 .mode           = 0644,
1279                 .proc_handler   = &sysctl_min_unmapped_ratio_sysctl_handler,
1280                 .strategy       = &sysctl_intvec,
1281                 .extra1         = &zero,
1282                 .extra2         = &one_hundred,
1283         },
1284         {
1285                 .ctl_name       = VM_MIN_SLAB,
1286                 .procname       = "min_slab_ratio",
1287                 .data           = &sysctl_min_slab_ratio,
1288                 .maxlen         = sizeof(sysctl_min_slab_ratio),
1289                 .mode           = 0644,
1290                 .proc_handler   = &sysctl_min_slab_ratio_sysctl_handler,
1291                 .strategy       = &sysctl_intvec,
1292                 .extra1         = &zero,
1293                 .extra2         = &one_hundred,
1294         },
1295 #endif
1296 #ifdef CONFIG_SMP
1297         {
1298                 .ctl_name       = CTL_UNNUMBERED,
1299                 .procname       = "stat_interval",
1300                 .data           = &sysctl_stat_interval,
1301                 .maxlen         = sizeof(sysctl_stat_interval),
1302                 .mode           = 0644,
1303                 .proc_handler   = &proc_dointvec_jiffies,
1304                 .strategy       = &sysctl_jiffies,
1305         },
1306 #endif
1307         {
1308                 .ctl_name       = CTL_UNNUMBERED,
1309                 .procname       = "mmap_min_addr",
1310                 .data           = &dac_mmap_min_addr,
1311                 .maxlen         = sizeof(unsigned long),
1312                 .mode           = 0644,
1313                 .proc_handler   = &mmap_min_addr_handler,
1314         },
1315 #ifdef CONFIG_NUMA
1316         {
1317                 .ctl_name       = CTL_UNNUMBERED,
1318                 .procname       = "numa_zonelist_order",
1319                 .data           = &numa_zonelist_order,
1320                 .maxlen         = NUMA_ZONELIST_ORDER_LEN,
1321                 .mode           = 0644,
1322                 .proc_handler   = &numa_zonelist_order_handler,
1323                 .strategy       = &sysctl_string,
1324         },
1325 #endif
1326 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1327    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1328         {
1329                 .ctl_name       = VM_VDSO_ENABLED,
1330                 .procname       = "vdso_enabled",
1331                 .data           = &vdso_enabled,
1332                 .maxlen         = sizeof(vdso_enabled),
1333                 .mode           = 0644,
1334                 .proc_handler   = &proc_dointvec,
1335                 .strategy       = &sysctl_intvec,
1336                 .extra1         = &zero,
1337         },
1338 #endif
1339 #ifdef CONFIG_HIGHMEM
1340         {
1341                 .ctl_name       = CTL_UNNUMBERED,
1342                 .procname       = "highmem_is_dirtyable",
1343                 .data           = &vm_highmem_is_dirtyable,
1344                 .maxlen         = sizeof(vm_highmem_is_dirtyable),
1345                 .mode           = 0644,
1346                 .proc_handler   = &proc_dointvec_minmax,
1347                 .strategy       = &sysctl_intvec,
1348                 .extra1         = &zero,
1349                 .extra2         = &one,
1350         },
1351 #endif
1352         {
1353                 .ctl_name       = CTL_UNNUMBERED,
1354                 .procname       = "scan_unevictable_pages",
1355                 .data           = &scan_unevictable_pages,
1356                 .maxlen         = sizeof(scan_unevictable_pages),
1357                 .mode           = 0644,
1358                 .proc_handler   = &scan_unevictable_handler,
1359         },
1360 /*
1361  * NOTE: do not add new entries to this table unless you have read
1362  * Documentation/sysctl/ctl_unnumbered.txt
1363  */
1364         { .ctl_name = 0 }
1365 };
1366
1367 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1368 static struct ctl_table binfmt_misc_table[] = {
1369         { .ctl_name = 0 }
1370 };
1371 #endif
1372
1373 static struct ctl_table fs_table[] = {
1374         {
1375                 .ctl_name       = FS_NRINODE,
1376                 .procname       = "inode-nr",
1377                 .data           = &inodes_stat,
1378                 .maxlen         = 2*sizeof(int),
1379                 .mode           = 0444,
1380                 .proc_handler   = &proc_dointvec,
1381         },
1382         {
1383                 .ctl_name       = FS_STATINODE,
1384                 .procname       = "inode-state",
1385                 .data           = &inodes_stat,
1386                 .maxlen         = 7*sizeof(int),
1387                 .mode           = 0444,
1388                 .proc_handler   = &proc_dointvec,
1389         },
1390         {
1391                 .procname       = "file-nr",
1392                 .data           = &files_stat,
1393                 .maxlen         = 3*sizeof(int),
1394                 .mode           = 0444,
1395                 .proc_handler   = &proc_nr_files,
1396         },
1397         {
1398                 .ctl_name       = FS_MAXFILE,
1399                 .procname       = "file-max",
1400                 .data           = &files_stat.max_files,
1401                 .maxlen         = sizeof(int),
1402                 .mode           = 0644,
1403                 .proc_handler   = &proc_dointvec,
1404         },
1405         {
1406                 .ctl_name       = CTL_UNNUMBERED,
1407                 .procname       = "nr_open",
1408                 .data           = &sysctl_nr_open,
1409                 .maxlen         = sizeof(int),
1410                 .mode           = 0644,
1411                 .proc_handler   = &proc_dointvec_minmax,
1412                 .extra1         = &sysctl_nr_open_min,
1413                 .extra2         = &sysctl_nr_open_max,
1414         },
1415         {
1416                 .ctl_name       = FS_DENTRY,
1417                 .procname       = "dentry-state",
1418                 .data           = &dentry_stat,
1419                 .maxlen         = 6*sizeof(int),
1420                 .mode           = 0444,
1421                 .proc_handler   = &proc_dointvec,
1422         },
1423         {
1424                 .ctl_name       = FS_OVERFLOWUID,
1425                 .procname       = "overflowuid",
1426                 .data           = &fs_overflowuid,
1427                 .maxlen         = sizeof(int),
1428                 .mode           = 0644,
1429                 .proc_handler   = &proc_dointvec_minmax,
1430                 .strategy       = &sysctl_intvec,
1431                 .extra1         = &minolduid,
1432                 .extra2         = &maxolduid,
1433         },
1434         {
1435                 .ctl_name       = FS_OVERFLOWGID,
1436                 .procname       = "overflowgid",
1437                 .data           = &fs_overflowgid,
1438                 .maxlen         = sizeof(int),
1439                 .mode           = 0644,
1440                 .proc_handler   = &proc_dointvec_minmax,
1441                 .strategy       = &sysctl_intvec,
1442                 .extra1         = &minolduid,
1443                 .extra2         = &maxolduid,
1444         },
1445 #ifdef CONFIG_FILE_LOCKING
1446         {
1447                 .ctl_name       = FS_LEASES,
1448                 .procname       = "leases-enable",
1449                 .data           = &leases_enable,
1450                 .maxlen         = sizeof(int),
1451                 .mode           = 0644,
1452                 .proc_handler   = &proc_dointvec,
1453         },
1454 #endif
1455 #ifdef CONFIG_DNOTIFY
1456         {
1457                 .ctl_name       = FS_DIR_NOTIFY,
1458                 .procname       = "dir-notify-enable",
1459                 .data           = &dir_notify_enable,
1460                 .maxlen         = sizeof(int),
1461                 .mode           = 0644,
1462                 .proc_handler   = &proc_dointvec,
1463         },
1464 #endif
1465 #ifdef CONFIG_MMU
1466 #ifdef CONFIG_FILE_LOCKING
1467         {
1468                 .ctl_name       = FS_LEASE_TIME,
1469                 .procname       = "lease-break-time",
1470                 .data           = &lease_break_time,
1471                 .maxlen         = sizeof(int),
1472                 .mode           = 0644,
1473                 .proc_handler   = &proc_dointvec,
1474         },
1475 #endif
1476 #ifdef CONFIG_AIO
1477         {
1478                 .procname       = "aio-nr",
1479                 .data           = &aio_nr,
1480                 .maxlen         = sizeof(aio_nr),
1481                 .mode           = 0444,
1482                 .proc_handler   = &proc_doulongvec_minmax,
1483         },
1484         {
1485                 .procname       = "aio-max-nr",
1486                 .data           = &aio_max_nr,
1487                 .maxlen         = sizeof(aio_max_nr),
1488                 .mode           = 0644,
1489                 .proc_handler   = &proc_doulongvec_minmax,
1490         },
1491 #endif /* CONFIG_AIO */
1492 #ifdef CONFIG_INOTIFY_USER
1493         {
1494                 .ctl_name       = FS_INOTIFY,
1495                 .procname       = "inotify",
1496                 .mode           = 0555,
1497                 .child          = inotify_table,
1498         },
1499 #endif  
1500 #ifdef CONFIG_EPOLL
1501         {
1502                 .procname       = "epoll",
1503                 .mode           = 0555,
1504                 .child          = epoll_table,
1505         },
1506 #endif
1507 #endif
1508         {
1509                 .ctl_name       = KERN_SETUID_DUMPABLE,
1510                 .procname       = "suid_dumpable",
1511                 .data           = &suid_dumpable,
1512                 .maxlen         = sizeof(int),
1513                 .mode           = 0644,
1514                 .proc_handler   = &proc_dointvec_minmax,
1515                 .strategy       = &sysctl_intvec,
1516                 .extra1         = &zero,
1517                 .extra2         = &two,
1518         },
1519 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1520         {
1521                 .ctl_name       = CTL_UNNUMBERED,
1522                 .procname       = "binfmt_misc",
1523                 .mode           = 0555,
1524                 .child          = binfmt_misc_table,
1525         },
1526 #endif
1527 /*
1528  * NOTE: do not add new entries to this table unless you have read
1529  * Documentation/sysctl/ctl_unnumbered.txt
1530  */
1531         { .ctl_name = 0 }
1532 };
1533
1534 static struct ctl_table debug_table[] = {
1535 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1536         {
1537                 .ctl_name       = CTL_UNNUMBERED,
1538                 .procname       = "exception-trace",
1539                 .data           = &show_unhandled_signals,
1540                 .maxlen         = sizeof(int),
1541                 .mode           = 0644,
1542                 .proc_handler   = proc_dointvec
1543         },
1544 #endif
1545         { .ctl_name = 0 }
1546 };
1547
1548 static struct ctl_table dev_table[] = {
1549         { .ctl_name = 0 }
1550 };
1551
1552 static DEFINE_SPINLOCK(sysctl_lock);
1553
1554 /* called under sysctl_lock */
1555 static int use_table(struct ctl_table_header *p)
1556 {
1557         if (unlikely(p->unregistering))
1558                 return 0;
1559         p->used++;
1560         return 1;
1561 }
1562
1563 /* called under sysctl_lock */
1564 static void unuse_table(struct ctl_table_header *p)
1565 {
1566         if (!--p->used)
1567                 if (unlikely(p->unregistering))
1568                         complete(p->unregistering);
1569 }
1570
1571 /* called under sysctl_lock, will reacquire if has to wait */
1572 static void start_unregistering(struct ctl_table_header *p)
1573 {
1574         /*
1575          * if p->used is 0, nobody will ever touch that entry again;
1576          * we'll eliminate all paths to it before dropping sysctl_lock
1577          */
1578         if (unlikely(p->used)) {
1579                 struct completion wait;
1580                 init_completion(&wait);
1581                 p->unregistering = &wait;
1582                 spin_unlock(&sysctl_lock);
1583                 wait_for_completion(&wait);
1584                 spin_lock(&sysctl_lock);
1585         } else {
1586                 /* anything non-NULL; we'll never dereference it */
1587                 p->unregistering = ERR_PTR(-EINVAL);
1588         }
1589         /*
1590          * do not remove from the list until nobody holds it; walking the
1591          * list in do_sysctl() relies on that.
1592          */
1593         list_del_init(&p->ctl_entry);
1594 }
1595
1596 void sysctl_head_get(struct ctl_table_header *head)
1597 {
1598         spin_lock(&sysctl_lock);
1599         head->count++;
1600         spin_unlock(&sysctl_lock);
1601 }
1602
1603 void sysctl_head_put(struct ctl_table_header *head)
1604 {
1605         spin_lock(&sysctl_lock);
1606         if (!--head->count)
1607                 kfree(head);
1608         spin_unlock(&sysctl_lock);
1609 }
1610
1611 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1612 {
1613         if (!head)
1614                 BUG();
1615         spin_lock(&sysctl_lock);
1616         if (!use_table(head))
1617                 head = ERR_PTR(-ENOENT);
1618         spin_unlock(&sysctl_lock);
1619         return head;
1620 }
1621
1622 void sysctl_head_finish(struct ctl_table_header *head)
1623 {
1624         if (!head)
1625                 return;
1626         spin_lock(&sysctl_lock);
1627         unuse_table(head);
1628         spin_unlock(&sysctl_lock);
1629 }
1630
1631 static struct ctl_table_set *
1632 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1633 {
1634         struct ctl_table_set *set = &root->default_set;
1635         if (root->lookup)
1636                 set = root->lookup(root, namespaces);
1637         return set;
1638 }
1639
1640 static struct list_head *
1641 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1642 {
1643         struct ctl_table_set *set = lookup_header_set(root, namespaces);
1644         return &set->list;
1645 }
1646
1647 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1648                                             struct ctl_table_header *prev)
1649 {
1650         struct ctl_table_root *root;
1651         struct list_head *header_list;
1652         struct ctl_table_header *head;
1653         struct list_head *tmp;
1654
1655         spin_lock(&sysctl_lock);
1656         if (prev) {
1657                 head = prev;
1658                 tmp = &prev->ctl_entry;
1659                 unuse_table(prev);
1660                 goto next;
1661         }
1662         tmp = &root_table_header.ctl_entry;
1663         for (;;) {
1664                 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1665
1666                 if (!use_table(head))
1667                         goto next;
1668                 spin_unlock(&sysctl_lock);
1669                 return head;
1670         next:
1671                 root = head->root;
1672                 tmp = tmp->next;
1673                 header_list = lookup_header_list(root, namespaces);
1674                 if (tmp != header_list)
1675                         continue;
1676
1677                 do {
1678                         root = list_entry(root->root_list.next,
1679                                         struct ctl_table_root, root_list);
1680                         if (root == &sysctl_table_root)
1681                                 goto out;
1682                         header_list = lookup_header_list(root, namespaces);
1683                 } while (list_empty(header_list));
1684                 tmp = header_list->next;
1685         }
1686 out:
1687         spin_unlock(&sysctl_lock);
1688         return NULL;
1689 }
1690
1691 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1692 {
1693         return __sysctl_head_next(current->nsproxy, prev);
1694 }
1695
1696 void register_sysctl_root(struct ctl_table_root *root)
1697 {
1698         spin_lock(&sysctl_lock);
1699         list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1700         spin_unlock(&sysctl_lock);
1701 }
1702
1703 #ifdef CONFIG_SYSCTL_SYSCALL
1704 /* Perform the actual read/write of a sysctl table entry. */
1705 static int do_sysctl_strategy(struct ctl_table_root *root,
1706                         struct ctl_table *table,
1707                         void __user *oldval, size_t __user *oldlenp,
1708                         void __user *newval, size_t newlen)
1709 {
1710         int op = 0, rc;
1711
1712         if (oldval)
1713                 op |= MAY_READ;
1714         if (newval)
1715                 op |= MAY_WRITE;
1716         if (sysctl_perm(root, table, op))
1717                 return -EPERM;
1718
1719         if (table->strategy) {
1720                 rc = table->strategy(table, oldval, oldlenp, newval, newlen);
1721                 if (rc < 0)
1722                         return rc;
1723                 if (rc > 0)
1724                         return 0;
1725         }
1726
1727         /* If there is no strategy routine, or if the strategy returns
1728          * zero, proceed with automatic r/w */
1729         if (table->data && table->maxlen) {
1730                 rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
1731                 if (rc < 0)
1732                         return rc;
1733         }
1734         return 0;
1735 }
1736
1737 static int parse_table(int __user *name, int nlen,
1738                        void __user *oldval, size_t __user *oldlenp,
1739                        void __user *newval, size_t newlen,
1740                        struct ctl_table_root *root,
1741                        struct ctl_table *table)
1742 {
1743         int n;
1744 repeat:
1745         if (!nlen)
1746                 return -ENOTDIR;
1747         if (get_user(n, name))
1748                 return -EFAULT;
1749         for ( ; table->ctl_name || table->procname; table++) {
1750                 if (!table->ctl_name)
1751                         continue;
1752                 if (n == table->ctl_name) {
1753                         int error;
1754                         if (table->child) {
1755                                 if (sysctl_perm(root, table, MAY_EXEC))
1756                                         return -EPERM;
1757                                 name++;
1758                                 nlen--;
1759                                 table = table->child;
1760                                 goto repeat;
1761                         }
1762                         error = do_sysctl_strategy(root, table,
1763                                                    oldval, oldlenp,
1764                                                    newval, newlen);
1765                         return error;
1766                 }
1767         }
1768         return -ENOTDIR;
1769 }
1770
1771 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1772                void __user *newval, size_t newlen)
1773 {
1774         struct ctl_table_header *head;
1775         int error = -ENOTDIR;
1776
1777         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1778                 return -ENOTDIR;
1779         if (oldval) {
1780                 int old_len;
1781                 if (!oldlenp || get_user(old_len, oldlenp))
1782                         return -EFAULT;
1783         }
1784
1785         for (head = sysctl_head_next(NULL); head;
1786                         head = sysctl_head_next(head)) {
1787                 error = parse_table(name, nlen, oldval, oldlenp, 
1788                                         newval, newlen,
1789                                         head->root, head->ctl_table);
1790                 if (error != -ENOTDIR) {
1791                         sysctl_head_finish(head);
1792                         break;
1793                 }
1794         }
1795         return error;
1796 }
1797
1798 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
1799 {
1800         struct __sysctl_args tmp;
1801         int error;
1802
1803         if (copy_from_user(&tmp, args, sizeof(tmp)))
1804                 return -EFAULT;
1805
1806         error = deprecated_sysctl_warning(&tmp);
1807         if (error)
1808                 goto out;
1809
1810         lock_kernel();
1811         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1812                           tmp.newval, tmp.newlen);
1813         unlock_kernel();
1814 out:
1815         return error;
1816 }
1817 #endif /* CONFIG_SYSCTL_SYSCALL */
1818
1819 /*
1820  * sysctl_perm does NOT grant the superuser all rights automatically, because
1821  * some sysctl variables are readonly even to root.
1822  */
1823
1824 static int test_perm(int mode, int op)
1825 {
1826         if (!current_euid())
1827                 mode >>= 6;
1828         else if (in_egroup_p(0))
1829                 mode >>= 3;
1830         if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1831                 return 0;
1832         return -EACCES;
1833 }
1834
1835 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1836 {
1837         int error;
1838         int mode;
1839
1840         error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1841         if (error)
1842                 return error;
1843
1844         if (root->permissions)
1845                 mode = root->permissions(root, current->nsproxy, table);
1846         else
1847                 mode = table->mode;
1848
1849         return test_perm(mode, op);
1850 }
1851
1852 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1853 {
1854         for (; table->ctl_name || table->procname; table++) {
1855                 table->parent = parent;
1856                 if (table->child)
1857                         sysctl_set_parent(table, table->child);
1858         }
1859 }
1860
1861 static __init int sysctl_init(void)
1862 {
1863         sysctl_set_parent(NULL, root_table);
1864 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1865         {
1866                 int err;
1867                 err = sysctl_check_table(current->nsproxy, root_table);
1868         }
1869 #endif
1870         return 0;
1871 }
1872
1873 core_initcall(sysctl_init);
1874
1875 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1876                                       struct ctl_table *table)
1877 {
1878         struct ctl_table *p;
1879         const char *s = branch->procname;
1880
1881         /* branch should have named subdirectory as its first element */
1882         if (!s || !branch->child)
1883                 return NULL;
1884
1885         /* ... and nothing else */
1886         if (branch[1].procname || branch[1].ctl_name)
1887                 return NULL;
1888
1889         /* table should contain subdirectory with the same name */
1890         for (p = table; p->procname || p->ctl_name; p++) {
1891                 if (!p->child)
1892                         continue;
1893                 if (p->procname && strcmp(p->procname, s) == 0)
1894                         return p;
1895         }
1896         return NULL;
1897 }
1898
1899 /* see if attaching q to p would be an improvement */
1900 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1901 {
1902         struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1903         struct ctl_table *next;
1904         int is_better = 0;
1905         int not_in_parent = !p->attached_by;
1906
1907         while ((next = is_branch_in(by, to)) != NULL) {
1908                 if (by == q->attached_by)
1909                         is_better = 1;
1910                 if (to == p->attached_by)
1911                         not_in_parent = 1;
1912                 by = by->child;
1913                 to = next->child;
1914         }
1915
1916         if (is_better && not_in_parent) {
1917                 q->attached_by = by;
1918                 q->attached_to = to;
1919                 q->parent = p;
1920         }
1921 }
1922
1923 /**
1924  * __register_sysctl_paths - register a sysctl hierarchy
1925  * @root: List of sysctl headers to register on
1926  * @namespaces: Data to compute which lists of sysctl entries are visible
1927  * @path: The path to the directory the sysctl table is in.
1928  * @table: the top-level table structure
1929  *
1930  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1931  * array. A completely 0 filled entry terminates the table.
1932  *
1933  * The members of the &struct ctl_table structure are used as follows:
1934  *
1935  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1936  *            must be unique within that level of sysctl
1937  *
1938  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1939  *            enter a sysctl file
1940  *
1941  * data - a pointer to data for use by proc_handler
1942  *
1943  * maxlen - the maximum size in bytes of the data
1944  *
1945  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1946  *
1947  * child - a pointer to the child sysctl table if this entry is a directory, or
1948  *         %NULL.
1949  *
1950  * proc_handler - the text handler routine (described below)
1951  *
1952  * strategy - the strategy routine (described below)
1953  *
1954  * de - for internal use by the sysctl routines
1955  *
1956  * extra1, extra2 - extra pointers usable by the proc handler routines
1957  *
1958  * Leaf nodes in the sysctl tree will be represented by a single file
1959  * under /proc; non-leaf nodes will be represented by directories.
1960  *
1961  * sysctl(2) can automatically manage read and write requests through
1962  * the sysctl table.  The data and maxlen fields of the ctl_table
1963  * struct enable minimal validation of the values being written to be
1964  * performed, and the mode field allows minimal authentication.
1965  *
1966  * More sophisticated management can be enabled by the provision of a
1967  * strategy routine with the table entry.  This will be called before
1968  * any automatic read or write of the data is performed.
1969  *
1970  * The strategy routine may return
1971  *
1972  * < 0 - Error occurred (error is passed to user process)
1973  *
1974  * 0   - OK - proceed with automatic read or write.
1975  *
1976  * > 0 - OK - read or write has been done by the strategy routine, so
1977  *       return immediately.
1978  *
1979  * There must be a proc_handler routine for any terminal nodes
1980  * mirrored under /proc/sys (non-terminals are handled by a built-in
1981  * directory handler).  Several default handlers are available to
1982  * cover common cases -
1983  *
1984  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1985  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(), 
1986  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1987  *
1988  * It is the handler's job to read the input buffer from user memory
1989  * and process it. The handler should return 0 on success.
1990  *
1991  * This routine returns %NULL on a failure to register, and a pointer
1992  * to the table header on success.
1993  */
1994 struct ctl_table_header *__register_sysctl_paths(
1995         struct ctl_table_root *root,
1996         struct nsproxy *namespaces,
1997         const struct ctl_path *path, struct ctl_table *table)
1998 {
1999         struct ctl_table_header *header;
2000         struct ctl_table *new, **prevp;
2001         unsigned int n, npath;
2002         struct ctl_table_set *set;
2003
2004         /* Count the path components */
2005         for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
2006                 ;
2007
2008         /*
2009          * For each path component, allocate a 2-element ctl_table array.
2010          * The first array element will be filled with the sysctl entry
2011          * for this, the second will be the sentinel (ctl_name == 0).
2012          *
2013          * We allocate everything in one go so that we don't have to
2014          * worry about freeing additional memory in unregister_sysctl_table.
2015          */
2016         header = kzalloc(sizeof(struct ctl_table_header) +
2017                          (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
2018         if (!header)
2019                 return NULL;
2020
2021         new = (struct ctl_table *) (header + 1);
2022
2023         /* Now connect the dots */
2024         prevp = &header->ctl_table;
2025         for (n = 0; n < npath; ++n, ++path) {
2026                 /* Copy the procname */
2027                 new->procname = path->procname;
2028                 new->ctl_name = path->ctl_name;
2029                 new->mode     = 0555;
2030
2031                 *prevp = new;
2032                 prevp = &new->child;
2033
2034                 new += 2;
2035         }
2036         *prevp = table;
2037         header->ctl_table_arg = table;
2038
2039         INIT_LIST_HEAD(&header->ctl_entry);
2040         header->used = 0;
2041         header->unregistering = NULL;
2042         header->root = root;
2043         sysctl_set_parent(NULL, header->ctl_table);
2044         header->count = 1;
2045 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
2046         if (sysctl_check_table(namespaces, header->ctl_table)) {
2047                 kfree(header);
2048                 return NULL;
2049         }
2050 #endif
2051         spin_lock(&sysctl_lock);
2052         header->set = lookup_header_set(root, namespaces);
2053         header->attached_by = header->ctl_table;
2054         header->attached_to = root_table;
2055         header->parent = &root_table_header;
2056         for (set = header->set; set; set = set->parent) {
2057                 struct ctl_table_header *p;
2058                 list_for_each_entry(p, &set->list, ctl_entry) {
2059                         if (p->unregistering)
2060                                 continue;
2061                         try_attach(p, header);
2062                 }
2063         }
2064         header->parent->count++;
2065         list_add_tail(&header->ctl_entry, &header->set->list);
2066         spin_unlock(&sysctl_lock);
2067
2068         return header;
2069 }
2070
2071 /**
2072  * register_sysctl_table_path - register a sysctl table hierarchy
2073  * @path: The path to the directory the sysctl table is in.
2074  * @table: the top-level table structure
2075  *
2076  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2077  * array. A completely 0 filled entry terminates the table.
2078  *
2079  * See __register_sysctl_paths for more details.
2080  */
2081 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2082                                                 struct ctl_table *table)
2083 {
2084         return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
2085                                         path, table);
2086 }
2087
2088 /**
2089  * register_sysctl_table - register a sysctl table hierarchy
2090  * @table: the top-level table structure
2091  *
2092  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2093  * array. A completely 0 filled entry terminates the table.
2094  *
2095  * See register_sysctl_paths for more details.
2096  */
2097 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
2098 {
2099         static const struct ctl_path null_path[] = { {} };
2100
2101         return register_sysctl_paths(null_path, table);
2102 }
2103
2104 /**
2105  * unregister_sysctl_table - unregister a sysctl table hierarchy
2106  * @header: the header returned from register_sysctl_table
2107  *
2108  * Unregisters the sysctl table and all children. proc entries may not
2109  * actually be removed until they are no longer used by anyone.
2110  */
2111 void unregister_sysctl_table(struct ctl_table_header * header)
2112 {
2113         might_sleep();
2114
2115         if (header == NULL)
2116                 return;
2117
2118         spin_lock(&sysctl_lock);
2119         start_unregistering(header);
2120         if (!--header->parent->count) {
2121                 WARN_ON(1);
2122                 kfree(header->parent);
2123         }
2124         if (!--header->count)
2125                 kfree(header);
2126         spin_unlock(&sysctl_lock);
2127 }
2128
2129 int sysctl_is_seen(struct ctl_table_header *p)
2130 {
2131         struct ctl_table_set *set = p->set;
2132         int res;
2133         spin_lock(&sysctl_lock);
2134         if (p->unregistering)
2135                 res = 0;
2136         else if (!set->is_seen)
2137                 res = 1;
2138         else
2139                 res = set->is_seen(set);
2140         spin_unlock(&sysctl_lock);
2141         return res;
2142 }
2143
2144 void setup_sysctl_set(struct ctl_table_set *p,
2145         struct ctl_table_set *parent,
2146         int (*is_seen)(struct ctl_table_set *))
2147 {
2148         INIT_LIST_HEAD(&p->list);
2149         p->parent = parent ? parent : &sysctl_table_root.default_set;
2150         p->is_seen = is_seen;
2151 }
2152
2153 #else /* !CONFIG_SYSCTL */
2154 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
2155 {
2156         return NULL;
2157 }
2158
2159 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2160                                                     struct ctl_table *table)
2161 {
2162         return NULL;
2163 }
2164
2165 void unregister_sysctl_table(struct ctl_table_header * table)
2166 {
2167 }
2168
2169 void setup_sysctl_set(struct ctl_table_set *p,
2170         struct ctl_table_set *parent,
2171         int (*is_seen)(struct ctl_table_set *))
2172 {
2173 }
2174
2175 void sysctl_head_put(struct ctl_table_header *head)
2176 {
2177 }
2178
2179 #endif /* CONFIG_SYSCTL */
2180
2181 /*
2182  * /proc/sys support
2183  */
2184
2185 #ifdef CONFIG_PROC_SYSCTL
2186
2187 static int _proc_do_string(void* data, int maxlen, int write,
2188                            struct file *filp, void __user *buffer,
2189                            size_t *lenp, loff_t *ppos)
2190 {
2191         size_t len;
2192         char __user *p;
2193         char c;
2194
2195         if (!data || !maxlen || !*lenp) {
2196                 *lenp = 0;
2197                 return 0;
2198         }
2199
2200         if (write) {
2201                 len = 0;
2202                 p = buffer;
2203                 while (len < *lenp) {
2204                         if (get_user(c, p++))
2205                                 return -EFAULT;
2206                         if (c == 0 || c == '\n')
2207                                 break;
2208                         len++;
2209                 }
2210                 if (len >= maxlen)
2211                         len = maxlen-1;
2212                 if(copy_from_user(data, buffer, len))
2213                         return -EFAULT;
2214                 ((char *) data)[len] = 0;
2215                 *ppos += *lenp;
2216         } else {
2217                 len = strlen(data);
2218                 if (len > maxlen)
2219                         len = maxlen;
2220
2221                 if (*ppos > len) {
2222                         *lenp = 0;
2223                         return 0;
2224                 }
2225
2226                 data += *ppos;
2227                 len  -= *ppos;
2228
2229                 if (len > *lenp)
2230                         len = *lenp;
2231                 if (len)
2232                         if(copy_to_user(buffer, data, len))
2233                                 return -EFAULT;
2234                 if (len < *lenp) {
2235                         if(put_user('\n', ((char __user *) buffer) + len))
2236                                 return -EFAULT;
2237                         len++;
2238                 }
2239                 *lenp = len;
2240                 *ppos += len;
2241         }
2242         return 0;
2243 }
2244
2245 /**
2246  * proc_dostring - read a string sysctl
2247  * @table: the sysctl table
2248  * @write: %TRUE if this is a write to the sysctl file
2249  * @filp: the file structure
2250  * @buffer: the user buffer
2251  * @lenp: the size of the user buffer
2252  * @ppos: file position
2253  *
2254  * Reads/writes a string from/to the user buffer. If the kernel
2255  * buffer provided is not large enough to hold the string, the
2256  * string is truncated. The copied string is %NULL-terminated.
2257  * If the string is being read by the user process, it is copied
2258  * and a newline '\n' is added. It is truncated if the buffer is
2259  * not large enough.
2260  *
2261  * Returns 0 on success.
2262  */
2263 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2264                   void __user *buffer, size_t *lenp, loff_t *ppos)
2265 {
2266         return _proc_do_string(table->data, table->maxlen, write, filp,
2267                                buffer, lenp, ppos);
2268 }
2269
2270
2271 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
2272                                  int *valp,
2273                                  int write, void *data)
2274 {
2275         if (write) {
2276                 *valp = *negp ? -*lvalp : *lvalp;
2277         } else {
2278                 int val = *valp;
2279                 if (val < 0) {
2280                         *negp = -1;
2281                         *lvalp = (unsigned long)-val;
2282                 } else {
2283                         *negp = 0;
2284                         *lvalp = (unsigned long)val;
2285                 }
2286         }
2287         return 0;
2288 }
2289
2290 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2291                   int write, struct file *filp, void __user *buffer,
2292                   size_t *lenp, loff_t *ppos,
2293                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2294                               int write, void *data),
2295                   void *data)
2296 {
2297 #define TMPBUFLEN 21
2298         int *i, vleft, first = 1, neg;
2299         unsigned long lval;
2300         size_t left, len;
2301         
2302         char buf[TMPBUFLEN], *p;
2303         char __user *s = buffer;
2304         
2305         if (!tbl_data || !table->maxlen || !*lenp ||
2306             (*ppos && !write)) {
2307                 *lenp = 0;
2308                 return 0;
2309         }
2310         
2311         i = (int *) tbl_data;
2312         vleft = table->maxlen / sizeof(*i);
2313         left = *lenp;
2314
2315         if (!conv)
2316                 conv = do_proc_dointvec_conv;
2317
2318         for (; left && vleft--; i++, first=0) {
2319                 if (write) {
2320                         while (left) {
2321                                 char c;
2322                                 if (get_user(c, s))
2323                                         return -EFAULT;
2324                                 if (!isspace(c))
2325                                         break;
2326                                 left--;
2327                                 s++;
2328                         }
2329                         if (!left)
2330                                 break;
2331                         neg = 0;
2332                         len = left;
2333                         if (len > sizeof(buf) - 1)
2334                                 len = sizeof(buf) - 1;
2335                         if (copy_from_user(buf, s, len))
2336                                 return -EFAULT;
2337                         buf[len] = 0;
2338                         p = buf;
2339                         if (*p == '-' && left > 1) {
2340                                 neg = 1;
2341                                 p++;
2342                         }
2343                         if (*p < '0' || *p > '9')
2344                                 break;
2345
2346                         lval = simple_strtoul(p, &p, 0);
2347
2348                         len = p-buf;
2349                         if ((len < left) && *p && !isspace(*p))
2350                                 break;
2351                         s += len;
2352                         left -= len;
2353
2354                         if (conv(&neg, &lval, i, 1, data))
2355                                 break;
2356                 } else {
2357                         p = buf;
2358                         if (!first)
2359                                 *p++ = '\t';
2360         
2361                         if (conv(&neg, &lval, i, 0, data))
2362                                 break;
2363
2364                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
2365                         len = strlen(buf);
2366                         if (len > left)
2367                                 len = left;
2368                         if(copy_to_user(s, buf, len))
2369                                 return -EFAULT;
2370                         left -= len;
2371                         s += len;
2372                 }
2373         }
2374
2375         if (!write && !first && left) {
2376                 if(put_user('\n', s))
2377                         return -EFAULT;
2378                 left--, s++;
2379         }
2380         if (write) {
2381                 while (left) {
2382                         char c;
2383                         if (get_user(c, s++))
2384                                 return -EFAULT;
2385                         if (!isspace(c))
2386                                 break;
2387                         left--;
2388                 }
2389         }
2390         if (write && first)
2391                 return -EINVAL;
2392         *lenp -= left;
2393         *ppos += *lenp;
2394         return 0;
2395 #undef TMPBUFLEN
2396 }
2397
2398 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2399                   void __user *buffer, size_t *lenp, loff_t *ppos,
2400                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2401                               int write, void *data),
2402                   void *data)
2403 {
2404         return __do_proc_dointvec(table->data, table, write, filp,
2405                         buffer, lenp, ppos, conv, data);
2406 }
2407
2408 /**
2409  * proc_dointvec - read a vector of integers
2410  * @table: the sysctl table
2411  * @write: %TRUE if this is a write to the sysctl file
2412  * @filp: the file structure
2413  * @buffer: the user buffer
2414  * @lenp: the size of the user buffer
2415  * @ppos: file position
2416  *
2417  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2418  * values from/to the user buffer, treated as an ASCII string. 
2419  *
2420  * Returns 0 on success.
2421  */
2422 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2423                      void __user *buffer, size_t *lenp, loff_t *ppos)
2424 {
2425     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2426                             NULL,NULL);
2427 }
2428
2429 /*
2430  * Taint values can only be increased
2431  * This means we can safely use a temporary.
2432  */
2433 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
2434                                void __user *buffer, size_t *lenp, loff_t *ppos)
2435 {
2436         struct ctl_table t;
2437         unsigned long tmptaint = get_taint();
2438         int err;
2439
2440         if (write && !capable(CAP_SYS_ADMIN))
2441                 return -EPERM;
2442
2443         t = *table;
2444         t.data = &tmptaint;
2445         err = proc_doulongvec_minmax(&t, write, filp, buffer, lenp, ppos);
2446         if (err < 0)
2447                 return err;
2448
2449         if (write) {
2450                 /*
2451                  * Poor man's atomic or. Not worth adding a primitive
2452                  * to everyone's atomic.h for this
2453                  */
2454                 int i;
2455                 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2456                         if ((tmptaint >> i) & 1)
2457                                 add_taint(i);
2458                 }
2459         }
2460
2461         return err;
2462 }
2463
2464 struct do_proc_dointvec_minmax_conv_param {
2465         int *min;
2466         int *max;
2467 };
2468
2469 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp, 
2470                                         int *valp, 
2471                                         int write, void *data)
2472 {
2473         struct do_proc_dointvec_minmax_conv_param *param = data;
2474         if (write) {
2475                 int val = *negp ? -*lvalp : *lvalp;
2476                 if ((param->min && *param->min > val) ||
2477                     (param->max && *param->max < val))
2478                         return -EINVAL;
2479                 *valp = val;
2480         } else {
2481                 int val = *valp;
2482                 if (val < 0) {
2483                         *negp = -1;
2484                         *lvalp = (unsigned long)-val;
2485                 } else {
2486                         *negp = 0;
2487                         *lvalp = (unsigned long)val;
2488                 }
2489         }
2490         return 0;
2491 }
2492
2493 /**
2494  * proc_dointvec_minmax - read a vector of integers with min/max values
2495  * @table: the sysctl table
2496  * @write: %TRUE if this is a write to the sysctl file
2497  * @filp: the file structure
2498  * @buffer: the user buffer
2499  * @lenp: the size of the user buffer
2500  * @ppos: file position
2501  *
2502  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2503  * values from/to the user buffer, treated as an ASCII string.
2504  *
2505  * This routine will ensure the values are within the range specified by
2506  * table->extra1 (min) and table->extra2 (max).
2507  *
2508  * Returns 0 on success.
2509  */
2510 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2511                   void __user *buffer, size_t *lenp, loff_t *ppos)
2512 {
2513         struct do_proc_dointvec_minmax_conv_param param = {
2514                 .min = (int *) table->extra1,
2515                 .max = (int *) table->extra2,
2516         };
2517         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2518                                 do_proc_dointvec_minmax_conv, &param);
2519 }
2520
2521 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2522                                      struct file *filp,
2523                                      void __user *buffer,
2524                                      size_t *lenp, loff_t *ppos,
2525                                      unsigned long convmul,
2526                                      unsigned long convdiv)
2527 {
2528 #define TMPBUFLEN 21
2529         unsigned long *i, *min, *max, val;
2530         int vleft, first=1, neg;
2531         size_t len, left;
2532         char buf[TMPBUFLEN], *p;
2533         char __user *s = buffer;
2534         
2535         if (!data || !table->maxlen || !*lenp ||
2536             (*ppos && !write)) {
2537                 *lenp = 0;
2538                 return 0;
2539         }
2540         
2541         i = (unsigned long *) data;
2542         min = (unsigned long *) table->extra1;
2543         max = (unsigned long *) table->extra2;
2544         vleft = table->maxlen / sizeof(unsigned long);
2545         left = *lenp;
2546         
2547         for (; left && vleft--; i++, min++, max++, first=0) {
2548                 if (write) {
2549                         while (left) {
2550                                 char c;
2551                                 if (get_user(c, s))
2552                                         return -EFAULT;
2553                                 if (!isspace(c))
2554                                         break;
2555                                 left--;
2556                                 s++;
2557                         }
2558                         if (!left)
2559                                 break;
2560                         neg = 0;
2561                         len = left;
2562                         if (len > TMPBUFLEN-1)
2563                                 len = TMPBUFLEN-1;
2564                         if (copy_from_user(buf, s, len))
2565                                 return -EFAULT;
2566                         buf[len] = 0;
2567                         p = buf;
2568                         if (*p == '-' && left > 1) {
2569                                 neg = 1;
2570                                 p++;
2571                         }
2572                         if (*p < '0' || *p > '9')
2573                                 break;
2574                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2575                         len = p-buf;
2576                         if ((len < left) && *p && !isspace(*p))
2577                                 break;
2578                         if (neg)
2579                                 val = -val;
2580                         s += len;
2581                         left -= len;
2582
2583                         if(neg)
2584                                 continue;
2585                         if ((min && val < *min) || (max && val > *max))
2586                                 continue;
2587                         *i = val;
2588                 } else {
2589                         p = buf;
2590                         if (!first)
2591                                 *p++ = '\t';
2592                         sprintf(p, "%lu", convdiv * (*i) / convmul);
2593                         len = strlen(buf);
2594                         if (len > left)
2595                                 len = left;
2596                         if(copy_to_user(s, buf, len))
2597                                 return -EFAULT;
2598                         left -= len;
2599                         s += len;
2600                 }
2601         }
2602
2603         if (!write && !first && left) {
2604                 if(put_user('\n', s))
2605                         return -EFAULT;
2606                 left--, s++;
2607         }
2608         if (write) {
2609                 while (left) {
2610                         char c;
2611                         if (get_user(c, s++))
2612                                 return -EFAULT;
2613                         if (!isspace(c))
2614                                 break;
2615                         left--;
2616                 }
2617         }
2618         if (write && first)
2619                 return -EINVAL;
2620         *lenp -= left;
2621         *ppos += *lenp;
2622         return 0;
2623 #undef TMPBUFLEN
2624 }
2625
2626 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2627                                      struct file *filp,
2628                                      void __user *buffer,
2629                                      size_t *lenp, loff_t *ppos,
2630                                      unsigned long convmul,
2631                                      unsigned long convdiv)
2632 {
2633         return __do_proc_doulongvec_minmax(table->data, table, write,
2634                         filp, buffer, lenp, ppos, convmul, convdiv);
2635 }
2636
2637 /**
2638  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2639  * @table: the sysctl table
2640  * @write: %TRUE if this is a write to the sysctl file
2641  * @filp: the file structure
2642  * @buffer: the user buffer
2643  * @lenp: the size of the user buffer
2644  * @ppos: file position
2645  *
2646  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2647  * values from/to the user buffer, treated as an ASCII string.
2648  *
2649  * This routine will ensure the values are within the range specified by
2650  * table->extra1 (min) and table->extra2 (max).
2651  *
2652  * Returns 0 on success.
2653  */
2654 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2655                            void __user *buffer, size_t *lenp, loff_t *ppos)
2656 {
2657     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2658 }
2659
2660 /**
2661  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2662  * @table: the sysctl table
2663  * @write: %TRUE if this is a write to the sysctl file
2664  * @filp: the file structure
2665  * @buffer: the user buffer
2666  * @lenp: the size of the user buffer
2667  * @ppos: file position
2668  *
2669  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2670  * values from/to the user buffer, treated as an ASCII string. The values
2671  * are treated as milliseconds, and converted to jiffies when they are stored.
2672  *
2673  * This routine will ensure the values are within the range specified by
2674  * table->extra1 (min) and table->extra2 (max).
2675  *
2676  * Returns 0 on success.
2677  */
2678 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2679                                       struct file *filp,
2680                                       void __user *buffer,
2681                                       size_t *lenp, loff_t *ppos)
2682 {
2683     return do_proc_doulongvec_minmax(table, write, filp, buffer,
2684                                      lenp, ppos, HZ, 1000l);
2685 }
2686
2687
2688 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2689                                          int *valp,
2690                                          int write, void *data)
2691 {
2692         if (write) {
2693                 if (*lvalp > LONG_MAX / HZ)
2694                         return 1;
2695                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2696         } else {
2697                 int val = *valp;
2698                 unsigned long lval;
2699                 if (val < 0) {
2700                         *negp = -1;
2701                         lval = (unsigned long)-val;
2702                 } else {
2703                         *negp = 0;
2704                         lval = (unsigned long)val;
2705                 }
2706                 *lvalp = lval / HZ;
2707         }
2708         return 0;
2709 }
2710
2711 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2712                                                 int *valp,
2713                                                 int write, void *data)
2714 {
2715         if (write) {
2716                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2717                         return 1;
2718                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2719         } else {
2720                 int val = *valp;
2721                 unsigned long lval;
2722                 if (val < 0) {
2723                         *negp = -1;
2724                         lval = (unsigned long)-val;
2725                 } else {
2726                         *negp = 0;
2727                         lval = (unsigned long)val;
2728                 }
2729                 *lvalp = jiffies_to_clock_t(lval);
2730         }
2731         return 0;
2732 }
2733
2734 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2735                                             int *valp,
2736                                             int write, void *data)
2737 {
2738         if (write) {
2739                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2740         } else {
2741                 int val = *valp;
2742                 unsigned long lval;
2743                 if (val < 0) {
2744                         *negp = -1;
2745                         lval = (unsigned long)-val;
2746                 } else {
2747                         *negp = 0;
2748                         lval = (unsigned long)val;
2749                 }
2750                 *lvalp = jiffies_to_msecs(lval);
2751         }
2752         return 0;
2753 }
2754
2755 /**
2756  * proc_dointvec_jiffies - read a vector of integers as seconds
2757  * @table: the sysctl table
2758  * @write: %TRUE if this is a write to the sysctl file
2759  * @filp: the file structure
2760  * @buffer: the user buffer
2761  * @lenp: the size of the user buffer
2762  * @ppos: file position
2763  *
2764  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2765  * values from/to the user buffer, treated as an ASCII string. 
2766  * The values read are assumed to be in seconds, and are converted into
2767  * jiffies.
2768  *
2769  * Returns 0 on success.
2770  */
2771 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2772                           void __user *buffer, size_t *lenp, loff_t *ppos)
2773 {
2774     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2775                             do_proc_dointvec_jiffies_conv,NULL);
2776 }
2777
2778 /**
2779  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2780  * @table: the sysctl table
2781  * @write: %TRUE if this is a write to the sysctl file
2782  * @filp: the file structure
2783  * @buffer: the user buffer
2784  * @lenp: the size of the user buffer
2785  * @ppos: pointer to the file position
2786  *
2787  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2788  * values from/to the user buffer, treated as an ASCII string. 
2789  * The values read are assumed to be in 1/USER_HZ seconds, and 
2790  * are converted into jiffies.
2791  *
2792  * Returns 0 on success.
2793  */
2794 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2795                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2796 {
2797     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2798                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2799 }
2800
2801 /**
2802  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2803  * @table: the sysctl table
2804  * @write: %TRUE if this is a write to the sysctl file
2805  * @filp: the file structure
2806  * @buffer: the user buffer
2807  * @lenp: the size of the user buffer
2808  * @ppos: file position
2809  * @ppos: the current position in the file
2810  *
2811  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2812  * values from/to the user buffer, treated as an ASCII string. 
2813  * The values read are assumed to be in 1/1000 seconds, and 
2814  * are converted into jiffies.
2815  *
2816  * Returns 0 on success.
2817  */
2818 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2819                              void __user *buffer, size_t *lenp, loff_t *ppos)
2820 {
2821         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2822                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2823 }
2824
2825 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2826                            void __user *buffer, size_t *lenp, loff_t *ppos)
2827 {
2828         struct pid *new_pid;
2829         pid_t tmp;
2830         int r;
2831
2832         tmp = pid_vnr(cad_pid);
2833
2834         r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2835                                lenp, ppos, NULL, NULL);
2836         if (r || !write)
2837                 return r;
2838
2839         new_pid = find_get_pid(tmp);
2840         if (!new_pid)
2841                 return -ESRCH;
2842
2843         put_pid(xchg(&cad_pid, new_pid));
2844         return 0;
2845 }
2846
2847 #else /* CONFIG_PROC_FS */
2848
2849 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2850                   void __user *buffer, size_t *lenp, loff_t *ppos)
2851 {
2852         return -ENOSYS;
2853 }
2854
2855 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2856                   void __user *buffer, size_t *lenp, loff_t *ppos)
2857 {
2858         return -ENOSYS;
2859 }
2860
2861 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2862                     void __user *buffer, size_t *lenp, loff_t *ppos)
2863 {
2864         return -ENOSYS;
2865 }
2866
2867 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2868                     void __user *buffer, size_t *lenp, loff_t *ppos)
2869 {
2870         return -ENOSYS;
2871 }
2872
2873 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2874                     void __user *buffer, size_t *lenp, loff_t *ppos)
2875 {
2876         return -ENOSYS;
2877 }
2878
2879 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2880                              void __user *buffer, size_t *lenp, loff_t *ppos)
2881 {
2882         return -ENOSYS;
2883 }
2884
2885 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2886                     void __user *buffer, size_t *lenp, loff_t *ppos)
2887 {
2888         return -ENOSYS;
2889 }
2890
2891 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2892                                       struct file *filp,
2893                                       void __user *buffer,
2894                                       size_t *lenp, loff_t *ppos)
2895 {
2896     return -ENOSYS;
2897 }
2898
2899
2900 #endif /* CONFIG_PROC_FS */
2901
2902
2903 #ifdef CONFIG_SYSCTL_SYSCALL
2904 /*
2905  * General sysctl support routines 
2906  */
2907
2908 /* The generic sysctl data routine (used if no strategy routine supplied) */
2909 int sysctl_data(struct ctl_table *table,
2910                 void __user *oldval, size_t __user *oldlenp,
2911                 void __user *newval, size_t newlen)
2912 {
2913         size_t len;
2914
2915         /* Get out of I don't have a variable */
2916         if (!table->data || !table->maxlen)
2917                 return -ENOTDIR;
2918
2919         if (oldval && oldlenp) {
2920                 if (get_user(len, oldlenp))
2921                         return -EFAULT;
2922                 if (len) {
2923                         if (len > table->maxlen)
2924                                 len = table->maxlen;
2925                         if (copy_to_user(oldval, table->data, len))
2926                                 return -EFAULT;
2927                         if (put_user(len, oldlenp))
2928                                 return -EFAULT;
2929                 }
2930         }
2931
2932         if (newval && newlen) {
2933                 if (newlen > table->maxlen)
2934                         newlen = table->maxlen;
2935
2936                 if (copy_from_user(table->data, newval, newlen))
2937                         return -EFAULT;
2938         }
2939         return 1;
2940 }
2941
2942 /* The generic string strategy routine: */
2943 int sysctl_string(struct ctl_table *table,
2944                   void __user *oldval, size_t __user *oldlenp,
2945                   void __user *newval, size_t newlen)
2946 {
2947         if (!table->data || !table->maxlen) 
2948                 return -ENOTDIR;
2949         
2950         if (oldval && oldlenp) {
2951                 size_t bufsize;
2952                 if (get_user(bufsize, oldlenp))
2953                         return -EFAULT;
2954                 if (bufsize) {
2955                         size_t len = strlen(table->data), copied;
2956
2957                         /* This shouldn't trigger for a well-formed sysctl */
2958                         if (len > table->maxlen)
2959                                 len = table->maxlen;
2960
2961                         /* Copy up to a max of bufsize-1 bytes of the string */
2962                         copied = (len >= bufsize) ? bufsize - 1 : len;
2963
2964                         if (copy_to_user(oldval, table->data, copied) ||
2965                             put_user(0, (char __user *)(oldval + copied)))
2966                                 return -EFAULT;
2967                         if (put_user(len, oldlenp))
2968                                 return -EFAULT;
2969                 }
2970         }
2971         if (newval && newlen) {
2972                 size_t len = newlen;
2973                 if (len > table->maxlen)
2974                         len = table->maxlen;
2975                 if(copy_from_user(table->data, newval, len))
2976                         return -EFAULT;
2977                 if (len == table->maxlen)
2978                         len--;
2979                 ((char *) table->data)[len] = 0;
2980         }
2981         return 1;
2982 }
2983
2984 /*
2985  * This function makes sure that all of the integers in the vector
2986  * are between the minimum and maximum values given in the arrays
2987  * table->extra1 and table->extra2, respectively.
2988  */
2989 int sysctl_intvec(struct ctl_table *table,
2990                 void __user *oldval, size_t __user *oldlenp,
2991                 void __user *newval, size_t newlen)
2992 {
2993
2994         if (newval && newlen) {
2995                 int __user *vec = (int __user *) newval;
2996                 int *min = (int *) table->extra1;
2997                 int *max = (int *) table->extra2;
2998                 size_t length;
2999                 int i;
3000
3001                 if (newlen % sizeof(int) != 0)
3002                         return -EINVAL;
3003
3004                 if (!table->extra1 && !table->extra2)
3005                         return 0;
3006
3007                 if (newlen > table->maxlen)
3008                         newlen = table->maxlen;
3009                 length = newlen / sizeof(int);
3010
3011                 for (i = 0; i < length; i++) {
3012                         int value;
3013                         if (get_user(value, vec + i))
3014                                 return -EFAULT;
3015                         if (min && value < min[i])
3016                                 return -EINVAL;
3017                         if (max && value > max[i])
3018                                 return -EINVAL;
3019                 }
3020         }
3021         return 0;
3022 }
3023
3024 /* Strategy function to convert jiffies to seconds */ 
3025 int sysctl_jiffies(struct ctl_table *table,
3026                 void __user *oldval, size_t __user *oldlenp,
3027                 void __user *newval, size_t newlen)
3028 {
3029         if (oldval && oldlenp) {
3030                 size_t olen;
3031
3032                 if (get_user(olen, oldlenp))
3033                         return -EFAULT;
3034                 if (olen) {
3035                         int val;
3036
3037                         if (olen < sizeof(int))
3038                                 return -EINVAL;
3039
3040                         val = *(int *)(table->data) / HZ;
3041                         if (put_user(val, (int __user *)oldval))
3042                                 return -EFAULT;
3043                         if (put_user(sizeof(int), oldlenp))
3044                                 return -EFAULT;
3045                 }
3046         }
3047         if (newval && newlen) { 
3048                 int new;
3049                 if (newlen != sizeof(int))
3050                         return -EINVAL; 
3051                 if (get_user(new, (int __user *)newval))
3052                         return -EFAULT;
3053                 *(int *)(table->data) = new*HZ; 
3054         }
3055         return 1;
3056 }
3057
3058 /* Strategy function to convert jiffies to seconds */ 
3059 int sysctl_ms_jiffies(struct ctl_table *table,
3060                 void __user *oldval, size_t __user *oldlenp,
3061                 void __user *newval, size_t newlen)
3062 {
3063         if (oldval && oldlenp) {
3064                 size_t olen;
3065
3066                 if (get_user(olen, oldlenp))
3067                         return -EFAULT;
3068                 if (olen) {
3069                         int val;
3070
3071                         if (olen < sizeof(int))
3072                                 return -EINVAL;
3073
3074                         val = jiffies_to_msecs(*(int *)(table->data));
3075                         if (put_user(val, (int __user *)oldval))
3076                                 return -EFAULT;
3077                         if (put_user(sizeof(int), oldlenp))
3078                                 return -EFAULT;
3079                 }
3080         }
3081         if (newval && newlen) { 
3082                 int new;
3083                 if (newlen != sizeof(int))
3084                         return -EINVAL; 
3085                 if (get_user(new, (int __user *)newval))
3086                         return -EFAULT;
3087                 *(int *)(table->data) = msecs_to_jiffies(new);
3088         }
3089         return 1;
3090 }
3091
3092
3093
3094 #else /* CONFIG_SYSCTL_SYSCALL */
3095
3096
3097 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
3098 {
3099         struct __sysctl_args tmp;
3100         int error;
3101
3102         if (copy_from_user(&tmp, args, sizeof(tmp)))
3103                 return -EFAULT;
3104
3105         error = deprecated_sysctl_warning(&tmp);
3106
3107         /* If no error reading the parameters then just -ENOSYS ... */
3108         if (!error)
3109                 error = -ENOSYS;
3110
3111         return error;
3112 }
3113
3114 int sysctl_data(struct ctl_table *table,
3115                   void __user *oldval, size_t __user *oldlenp,
3116                   void __user *newval, size_t newlen)
3117 {
3118         return -ENOSYS;
3119 }
3120
3121 int sysctl_string(struct ctl_table *table,
3122                   void __user *oldval, size_t __user *oldlenp,
3123                   void __user *newval, size_t newlen)
3124 {
3125         return -ENOSYS;
3126 }
3127
3128 int sysctl_intvec(struct ctl_table *table,
3129                 void __user *oldval, size_t __user *oldlenp,
3130                 void __user *newval, size_t newlen)
3131 {
3132         return -ENOSYS;
3133 }
3134
3135 int sysctl_jiffies(struct ctl_table *table,
3136                 void __user *oldval, size_t __user *oldlenp,
3137                 void __user *newval, size_t newlen)
3138 {
3139         return -ENOSYS;
3140 }
3141
3142 int sysctl_ms_jiffies(struct ctl_table *table,
3143                 void __user *oldval, size_t __user *oldlenp,
3144                 void __user *newval, size_t newlen)
3145 {
3146         return -ENOSYS;
3147 }
3148
3149 #endif /* CONFIG_SYSCTL_SYSCALL */
3150
3151 static int deprecated_sysctl_warning(struct __sysctl_args *args)
3152 {
3153         static int msg_count;
3154         int name[CTL_MAXNAME];
3155         int i;
3156
3157         /* Check args->nlen. */
3158         if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
3159                 return -ENOTDIR;
3160
3161         /* Read in the sysctl name for better debug message logging */
3162         for (i = 0; i < args->nlen; i++)
3163                 if (get_user(name[i], args->name + i))
3164                         return -EFAULT;
3165
3166         /* Ignore accesses to kernel.version */
3167         if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
3168                 return 0;
3169
3170         if (msg_count < 5) {
3171                 msg_count++;
3172                 printk(KERN_INFO
3173                         "warning: process `%s' used the deprecated sysctl "
3174                         "system call with ", current->comm);
3175                 for (i = 0; i < args->nlen; i++)
3176                         printk("%d.", name[i]);
3177                 printk("\n");
3178         }
3179         return 0;
3180 }
3181
3182 /*
3183  * No sense putting this after each symbol definition, twice,
3184  * exception granted :-)
3185  */
3186 EXPORT_SYMBOL(proc_dointvec);
3187 EXPORT_SYMBOL(proc_dointvec_jiffies);
3188 EXPORT_SYMBOL(proc_dointvec_minmax);
3189 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3190 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3191 EXPORT_SYMBOL(proc_dostring);
3192 EXPORT_SYMBOL(proc_doulongvec_minmax);
3193 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3194 EXPORT_SYMBOL(register_sysctl_table);
3195 EXPORT_SYMBOL(register_sysctl_paths);
3196 EXPORT_SYMBOL(sysctl_intvec);
3197 EXPORT_SYMBOL(sysctl_jiffies);
3198 EXPORT_SYMBOL(sysctl_ms_jiffies);
3199 EXPORT_SYMBOL(sysctl_string);
3200 EXPORT_SYMBOL(sysctl_data);
3201 EXPORT_SYMBOL(unregister_sysctl_table);