unfuck proc_sysctl ->d_compare()
[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/signal.h>
27 #include <linux/printk.h>
28 #include <linux/proc_fs.h>
29 #include <linux/security.h>
30 #include <linux/ctype.h>
31 #include <linux/kmemcheck.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/ratelimit.h>
41 #include <linux/compaction.h>
42 #include <linux/hugetlb.h>
43 #include <linux/initrd.h>
44 #include <linux/key.h>
45 #include <linux/times.h>
46 #include <linux/limits.h>
47 #include <linux/dcache.h>
48 #include <linux/dnotify.h>
49 #include <linux/syscalls.h>
50 #include <linux/vmstat.h>
51 #include <linux/nfs_fs.h>
52 #include <linux/acpi.h>
53 #include <linux/reboot.h>
54 #include <linux/ftrace.h>
55 #include <linux/perf_event.h>
56 #include <linux/kprobes.h>
57 #include <linux/pipe_fs_i.h>
58 #include <linux/oom.h>
59
60 #include <asm/uaccess.h>
61 #include <asm/processor.h>
62
63 #ifdef CONFIG_X86
64 #include <asm/nmi.h>
65 #include <asm/stacktrace.h>
66 #include <asm/io.h>
67 #endif
68 #ifdef CONFIG_BSD_PROCESS_ACCT
69 #include <linux/acct.h>
70 #endif
71 #ifdef CONFIG_RT_MUTEXES
72 #include <linux/rtmutex.h>
73 #endif
74 #if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT)
75 #include <linux/lockdep.h>
76 #endif
77 #ifdef CONFIG_CHR_DEV_SG
78 #include <scsi/sg.h>
79 #endif
80
81 #ifdef CONFIG_LOCKUP_DETECTOR
82 #include <linux/nmi.h>
83 #endif
84
85
86 #if defined(CONFIG_SYSCTL)
87
88 /* External variables not in a header file. */
89 extern int sysctl_overcommit_memory;
90 extern int sysctl_overcommit_ratio;
91 extern int max_threads;
92 extern int core_uses_pid;
93 extern int suid_dumpable;
94 extern char core_pattern[];
95 extern unsigned int core_pipe_limit;
96 extern int pid_max;
97 extern int min_free_kbytes;
98 extern int pid_max_min, pid_max_max;
99 extern int sysctl_drop_caches;
100 extern int percpu_pagelist_fraction;
101 extern int compat_log;
102 extern int latencytop_enabled;
103 extern int sysctl_nr_open_min, sysctl_nr_open_max;
104 #ifndef CONFIG_MMU
105 extern int sysctl_nr_trim_pages;
106 #endif
107 #ifdef CONFIG_BLOCK
108 extern int blk_iopoll_enabled;
109 #endif
110
111 /* Constants used for minimum and  maximum */
112 #ifdef CONFIG_LOCKUP_DETECTOR
113 static int sixty = 60;
114 static int neg_one = -1;
115 #endif
116
117 static int zero;
118 static int __maybe_unused one = 1;
119 static int __maybe_unused two = 2;
120 static unsigned long one_ul = 1;
121 static int one_hundred = 100;
122 #ifdef CONFIG_PRINTK
123 static int ten_thousand = 10000;
124 #endif
125
126 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
127 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
128
129 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
130 static int maxolduid = 65535;
131 static int minolduid;
132 static int min_percpu_pagelist_fract = 8;
133
134 static int ngroups_max = NGROUPS_MAX;
135
136 #ifdef CONFIG_INOTIFY_USER
137 #include <linux/inotify.h>
138 #endif
139 #ifdef CONFIG_SPARC
140 #include <asm/system.h>
141 #endif
142
143 #ifdef CONFIG_SPARC64
144 extern int sysctl_tsb_ratio;
145 #endif
146
147 #ifdef __hppa__
148 extern int pwrsw_enabled;
149 extern int unaligned_enabled;
150 #endif
151
152 #ifdef CONFIG_S390
153 #ifdef CONFIG_MATHEMU
154 extern int sysctl_ieee_emulation_warnings;
155 #endif
156 extern int sysctl_userprocess_debug;
157 extern int spin_retry;
158 #endif
159
160 #ifdef CONFIG_IA64
161 extern int no_unaligned_warning;
162 extern int unaligned_dump_stack;
163 #endif
164
165 #ifdef CONFIG_PROC_SYSCTL
166 static int proc_do_cad_pid(struct ctl_table *table, int write,
167                   void __user *buffer, size_t *lenp, loff_t *ppos);
168 static int proc_taint(struct ctl_table *table, int write,
169                                void __user *buffer, size_t *lenp, loff_t *ppos);
170 #endif
171
172 #ifdef CONFIG_MAGIC_SYSRQ
173 /* Note: sysrq code uses it's own private copy */
174 static int __sysrq_enabled = SYSRQ_DEFAULT_ENABLE;
175
176 static int sysrq_sysctl_handler(ctl_table *table, int write,
177                                 void __user *buffer, size_t *lenp,
178                                 loff_t *ppos)
179 {
180         int error;
181
182         error = proc_dointvec(table, write, buffer, lenp, ppos);
183         if (error)
184                 return error;
185
186         if (write)
187                 sysrq_toggle_support(__sysrq_enabled);
188
189         return 0;
190 }
191
192 #endif
193
194 static struct ctl_table root_table[];
195 static struct ctl_table_root sysctl_table_root;
196 static struct ctl_table_header root_table_header = {
197         {{.count = 1,
198         .ctl_table = root_table,
199         .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),}},
200         .root = &sysctl_table_root,
201         .set = &sysctl_table_root.default_set,
202 };
203 static struct ctl_table_root sysctl_table_root = {
204         .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
205         .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
206 };
207
208 static struct ctl_table kern_table[];
209 static struct ctl_table vm_table[];
210 static struct ctl_table fs_table[];
211 static struct ctl_table debug_table[];
212 static struct ctl_table dev_table[];
213 extern struct ctl_table random_table[];
214 #ifdef CONFIG_EPOLL
215 extern struct ctl_table epoll_table[];
216 #endif
217
218 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
219 int sysctl_legacy_va_layout;
220 #endif
221
222 /* The default sysctl tables: */
223
224 static struct ctl_table root_table[] = {
225         {
226                 .procname       = "kernel",
227                 .mode           = 0555,
228                 .child          = kern_table,
229         },
230         {
231                 .procname       = "vm",
232                 .mode           = 0555,
233                 .child          = vm_table,
234         },
235         {
236                 .procname       = "fs",
237                 .mode           = 0555,
238                 .child          = fs_table,
239         },
240         {
241                 .procname       = "debug",
242                 .mode           = 0555,
243                 .child          = debug_table,
244         },
245         {
246                 .procname       = "dev",
247                 .mode           = 0555,
248                 .child          = dev_table,
249         },
250         { }
251 };
252
253 #ifdef CONFIG_SCHED_DEBUG
254 static int min_sched_granularity_ns = 100000;           /* 100 usecs */
255 static int max_sched_granularity_ns = NSEC_PER_SEC;     /* 1 second */
256 static int min_wakeup_granularity_ns;                   /* 0 usecs */
257 static int max_wakeup_granularity_ns = NSEC_PER_SEC;    /* 1 second */
258 static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
259 static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
260 #endif
261
262 #ifdef CONFIG_COMPACTION
263 static int min_extfrag_threshold;
264 static int max_extfrag_threshold = 1000;
265 #endif
266
267 static struct ctl_table kern_table[] = {
268         {
269                 .procname       = "sched_child_runs_first",
270                 .data           = &sysctl_sched_child_runs_first,
271                 .maxlen         = sizeof(unsigned int),
272                 .mode           = 0644,
273                 .proc_handler   = proc_dointvec,
274         },
275 #ifdef CONFIG_SCHED_DEBUG
276         {
277                 .procname       = "sched_min_granularity_ns",
278                 .data           = &sysctl_sched_min_granularity,
279                 .maxlen         = sizeof(unsigned int),
280                 .mode           = 0644,
281                 .proc_handler   = sched_proc_update_handler,
282                 .extra1         = &min_sched_granularity_ns,
283                 .extra2         = &max_sched_granularity_ns,
284         },
285         {
286                 .procname       = "sched_latency_ns",
287                 .data           = &sysctl_sched_latency,
288                 .maxlen         = sizeof(unsigned int),
289                 .mode           = 0644,
290                 .proc_handler   = sched_proc_update_handler,
291                 .extra1         = &min_sched_granularity_ns,
292                 .extra2         = &max_sched_granularity_ns,
293         },
294         {
295                 .procname       = "sched_wakeup_granularity_ns",
296                 .data           = &sysctl_sched_wakeup_granularity,
297                 .maxlen         = sizeof(unsigned int),
298                 .mode           = 0644,
299                 .proc_handler   = sched_proc_update_handler,
300                 .extra1         = &min_wakeup_granularity_ns,
301                 .extra2         = &max_wakeup_granularity_ns,
302         },
303         {
304                 .procname       = "sched_tunable_scaling",
305                 .data           = &sysctl_sched_tunable_scaling,
306                 .maxlen         = sizeof(enum sched_tunable_scaling),
307                 .mode           = 0644,
308                 .proc_handler   = sched_proc_update_handler,
309                 .extra1         = &min_sched_tunable_scaling,
310                 .extra2         = &max_sched_tunable_scaling,
311         },
312         {
313                 .procname       = "sched_migration_cost",
314                 .data           = &sysctl_sched_migration_cost,
315                 .maxlen         = sizeof(unsigned int),
316                 .mode           = 0644,
317                 .proc_handler   = proc_dointvec,
318         },
319         {
320                 .procname       = "sched_nr_migrate",
321                 .data           = &sysctl_sched_nr_migrate,
322                 .maxlen         = sizeof(unsigned int),
323                 .mode           = 0644,
324                 .proc_handler   = proc_dointvec,
325         },
326         {
327                 .procname       = "sched_time_avg",
328                 .data           = &sysctl_sched_time_avg,
329                 .maxlen         = sizeof(unsigned int),
330                 .mode           = 0644,
331                 .proc_handler   = proc_dointvec,
332         },
333         {
334                 .procname       = "sched_shares_window",
335                 .data           = &sysctl_sched_shares_window,
336                 .maxlen         = sizeof(unsigned int),
337                 .mode           = 0644,
338                 .proc_handler   = proc_dointvec,
339         },
340         {
341                 .procname       = "timer_migration",
342                 .data           = &sysctl_timer_migration,
343                 .maxlen         = sizeof(unsigned int),
344                 .mode           = 0644,
345                 .proc_handler   = proc_dointvec_minmax,
346                 .extra1         = &zero,
347                 .extra2         = &one,
348         },
349 #endif
350         {
351                 .procname       = "sched_rt_period_us",
352                 .data           = &sysctl_sched_rt_period,
353                 .maxlen         = sizeof(unsigned int),
354                 .mode           = 0644,
355                 .proc_handler   = sched_rt_handler,
356         },
357         {
358                 .procname       = "sched_rt_runtime_us",
359                 .data           = &sysctl_sched_rt_runtime,
360                 .maxlen         = sizeof(int),
361                 .mode           = 0644,
362                 .proc_handler   = sched_rt_handler,
363         },
364         {
365                 .procname       = "sched_compat_yield",
366                 .data           = &sysctl_sched_compat_yield,
367                 .maxlen         = sizeof(unsigned int),
368                 .mode           = 0644,
369                 .proc_handler   = proc_dointvec,
370         },
371 #ifdef CONFIG_SCHED_AUTOGROUP
372         {
373                 .procname       = "sched_autogroup_enabled",
374                 .data           = &sysctl_sched_autogroup_enabled,
375                 .maxlen         = sizeof(unsigned int),
376                 .mode           = 0644,
377                 .proc_handler   = proc_dointvec,
378                 .extra1         = &zero,
379                 .extra2         = &one,
380         },
381 #endif
382 #ifdef CONFIG_PROVE_LOCKING
383         {
384                 .procname       = "prove_locking",
385                 .data           = &prove_locking,
386                 .maxlen         = sizeof(int),
387                 .mode           = 0644,
388                 .proc_handler   = proc_dointvec,
389         },
390 #endif
391 #ifdef CONFIG_LOCK_STAT
392         {
393                 .procname       = "lock_stat",
394                 .data           = &lock_stat,
395                 .maxlen         = sizeof(int),
396                 .mode           = 0644,
397                 .proc_handler   = proc_dointvec,
398         },
399 #endif
400         {
401                 .procname       = "panic",
402                 .data           = &panic_timeout,
403                 .maxlen         = sizeof(int),
404                 .mode           = 0644,
405                 .proc_handler   = proc_dointvec,
406         },
407         {
408                 .procname       = "core_uses_pid",
409                 .data           = &core_uses_pid,
410                 .maxlen         = sizeof(int),
411                 .mode           = 0644,
412                 .proc_handler   = proc_dointvec,
413         },
414         {
415                 .procname       = "core_pattern",
416                 .data           = core_pattern,
417                 .maxlen         = CORENAME_MAX_SIZE,
418                 .mode           = 0644,
419                 .proc_handler   = proc_dostring,
420         },
421         {
422                 .procname       = "core_pipe_limit",
423                 .data           = &core_pipe_limit,
424                 .maxlen         = sizeof(unsigned int),
425                 .mode           = 0644,
426                 .proc_handler   = proc_dointvec,
427         },
428 #ifdef CONFIG_PROC_SYSCTL
429         {
430                 .procname       = "tainted",
431                 .maxlen         = sizeof(long),
432                 .mode           = 0644,
433                 .proc_handler   = proc_taint,
434         },
435 #endif
436 #ifdef CONFIG_LATENCYTOP
437         {
438                 .procname       = "latencytop",
439                 .data           = &latencytop_enabled,
440                 .maxlen         = sizeof(int),
441                 .mode           = 0644,
442                 .proc_handler   = proc_dointvec,
443         },
444 #endif
445 #ifdef CONFIG_BLK_DEV_INITRD
446         {
447                 .procname       = "real-root-dev",
448                 .data           = &real_root_dev,
449                 .maxlen         = sizeof(int),
450                 .mode           = 0644,
451                 .proc_handler   = proc_dointvec,
452         },
453 #endif
454         {
455                 .procname       = "print-fatal-signals",
456                 .data           = &print_fatal_signals,
457                 .maxlen         = sizeof(int),
458                 .mode           = 0644,
459                 .proc_handler   = proc_dointvec,
460         },
461 #ifdef CONFIG_SPARC
462         {
463                 .procname       = "reboot-cmd",
464                 .data           = reboot_command,
465                 .maxlen         = 256,
466                 .mode           = 0644,
467                 .proc_handler   = proc_dostring,
468         },
469         {
470                 .procname       = "stop-a",
471                 .data           = &stop_a_enabled,
472                 .maxlen         = sizeof (int),
473                 .mode           = 0644,
474                 .proc_handler   = proc_dointvec,
475         },
476         {
477                 .procname       = "scons-poweroff",
478                 .data           = &scons_pwroff,
479                 .maxlen         = sizeof (int),
480                 .mode           = 0644,
481                 .proc_handler   = proc_dointvec,
482         },
483 #endif
484 #ifdef CONFIG_SPARC64
485         {
486                 .procname       = "tsb-ratio",
487                 .data           = &sysctl_tsb_ratio,
488                 .maxlen         = sizeof (int),
489                 .mode           = 0644,
490                 .proc_handler   = proc_dointvec,
491         },
492 #endif
493 #ifdef __hppa__
494         {
495                 .procname       = "soft-power",
496                 .data           = &pwrsw_enabled,
497                 .maxlen         = sizeof (int),
498                 .mode           = 0644,
499                 .proc_handler   = proc_dointvec,
500         },
501         {
502                 .procname       = "unaligned-trap",
503                 .data           = &unaligned_enabled,
504                 .maxlen         = sizeof (int),
505                 .mode           = 0644,
506                 .proc_handler   = proc_dointvec,
507         },
508 #endif
509         {
510                 .procname       = "ctrl-alt-del",
511                 .data           = &C_A_D,
512                 .maxlen         = sizeof(int),
513                 .mode           = 0644,
514                 .proc_handler   = proc_dointvec,
515         },
516 #ifdef CONFIG_FUNCTION_TRACER
517         {
518                 .procname       = "ftrace_enabled",
519                 .data           = &ftrace_enabled,
520                 .maxlen         = sizeof(int),
521                 .mode           = 0644,
522                 .proc_handler   = ftrace_enable_sysctl,
523         },
524 #endif
525 #ifdef CONFIG_STACK_TRACER
526         {
527                 .procname       = "stack_tracer_enabled",
528                 .data           = &stack_tracer_enabled,
529                 .maxlen         = sizeof(int),
530                 .mode           = 0644,
531                 .proc_handler   = stack_trace_sysctl,
532         },
533 #endif
534 #ifdef CONFIG_TRACING
535         {
536                 .procname       = "ftrace_dump_on_oops",
537                 .data           = &ftrace_dump_on_oops,
538                 .maxlen         = sizeof(int),
539                 .mode           = 0644,
540                 .proc_handler   = proc_dointvec,
541         },
542 #endif
543 #ifdef CONFIG_MODULES
544         {
545                 .procname       = "modprobe",
546                 .data           = &modprobe_path,
547                 .maxlen         = KMOD_PATH_LEN,
548                 .mode           = 0644,
549                 .proc_handler   = proc_dostring,
550         },
551         {
552                 .procname       = "modules_disabled",
553                 .data           = &modules_disabled,
554                 .maxlen         = sizeof(int),
555                 .mode           = 0644,
556                 /* only handle a transition from default "0" to "1" */
557                 .proc_handler   = proc_dointvec_minmax,
558                 .extra1         = &one,
559                 .extra2         = &one,
560         },
561 #endif
562 #ifdef CONFIG_HOTPLUG
563         {
564                 .procname       = "hotplug",
565                 .data           = &uevent_helper,
566                 .maxlen         = UEVENT_HELPER_PATH_LEN,
567                 .mode           = 0644,
568                 .proc_handler   = proc_dostring,
569         },
570 #endif
571 #ifdef CONFIG_CHR_DEV_SG
572         {
573                 .procname       = "sg-big-buff",
574                 .data           = &sg_big_buff,
575                 .maxlen         = sizeof (int),
576                 .mode           = 0444,
577                 .proc_handler   = proc_dointvec,
578         },
579 #endif
580 #ifdef CONFIG_BSD_PROCESS_ACCT
581         {
582                 .procname       = "acct",
583                 .data           = &acct_parm,
584                 .maxlen         = 3*sizeof(int),
585                 .mode           = 0644,
586                 .proc_handler   = proc_dointvec,
587         },
588 #endif
589 #ifdef CONFIG_MAGIC_SYSRQ
590         {
591                 .procname       = "sysrq",
592                 .data           = &__sysrq_enabled,
593                 .maxlen         = sizeof (int),
594                 .mode           = 0644,
595                 .proc_handler   = sysrq_sysctl_handler,
596         },
597 #endif
598 #ifdef CONFIG_PROC_SYSCTL
599         {
600                 .procname       = "cad_pid",
601                 .data           = NULL,
602                 .maxlen         = sizeof (int),
603                 .mode           = 0600,
604                 .proc_handler   = proc_do_cad_pid,
605         },
606 #endif
607         {
608                 .procname       = "threads-max",
609                 .data           = &max_threads,
610                 .maxlen         = sizeof(int),
611                 .mode           = 0644,
612                 .proc_handler   = proc_dointvec,
613         },
614         {
615                 .procname       = "random",
616                 .mode           = 0555,
617                 .child          = random_table,
618         },
619         {
620                 .procname       = "overflowuid",
621                 .data           = &overflowuid,
622                 .maxlen         = sizeof(int),
623                 .mode           = 0644,
624                 .proc_handler   = proc_dointvec_minmax,
625                 .extra1         = &minolduid,
626                 .extra2         = &maxolduid,
627         },
628         {
629                 .procname       = "overflowgid",
630                 .data           = &overflowgid,
631                 .maxlen         = sizeof(int),
632                 .mode           = 0644,
633                 .proc_handler   = proc_dointvec_minmax,
634                 .extra1         = &minolduid,
635                 .extra2         = &maxolduid,
636         },
637 #ifdef CONFIG_S390
638 #ifdef CONFIG_MATHEMU
639         {
640                 .procname       = "ieee_emulation_warnings",
641                 .data           = &sysctl_ieee_emulation_warnings,
642                 .maxlen         = sizeof(int),
643                 .mode           = 0644,
644                 .proc_handler   = proc_dointvec,
645         },
646 #endif
647         {
648                 .procname       = "userprocess_debug",
649                 .data           = &show_unhandled_signals,
650                 .maxlen         = sizeof(int),
651                 .mode           = 0644,
652                 .proc_handler   = proc_dointvec,
653         },
654 #endif
655         {
656                 .procname       = "pid_max",
657                 .data           = &pid_max,
658                 .maxlen         = sizeof (int),
659                 .mode           = 0644,
660                 .proc_handler   = proc_dointvec_minmax,
661                 .extra1         = &pid_max_min,
662                 .extra2         = &pid_max_max,
663         },
664         {
665                 .procname       = "panic_on_oops",
666                 .data           = &panic_on_oops,
667                 .maxlen         = sizeof(int),
668                 .mode           = 0644,
669                 .proc_handler   = proc_dointvec,
670         },
671 #if defined CONFIG_PRINTK
672         {
673                 .procname       = "printk",
674                 .data           = &console_loglevel,
675                 .maxlen         = 4*sizeof(int),
676                 .mode           = 0644,
677                 .proc_handler   = proc_dointvec,
678         },
679         {
680                 .procname       = "printk_ratelimit",
681                 .data           = &printk_ratelimit_state.interval,
682                 .maxlen         = sizeof(int),
683                 .mode           = 0644,
684                 .proc_handler   = proc_dointvec_jiffies,
685         },
686         {
687                 .procname       = "printk_ratelimit_burst",
688                 .data           = &printk_ratelimit_state.burst,
689                 .maxlen         = sizeof(int),
690                 .mode           = 0644,
691                 .proc_handler   = proc_dointvec,
692         },
693         {
694                 .procname       = "printk_delay",
695                 .data           = &printk_delay_msec,
696                 .maxlen         = sizeof(int),
697                 .mode           = 0644,
698                 .proc_handler   = proc_dointvec_minmax,
699                 .extra1         = &zero,
700                 .extra2         = &ten_thousand,
701         },
702         {
703                 .procname       = "dmesg_restrict",
704                 .data           = &dmesg_restrict,
705                 .maxlen         = sizeof(int),
706                 .mode           = 0644,
707                 .proc_handler   = proc_dointvec_minmax,
708                 .extra1         = &zero,
709                 .extra2         = &one,
710         },
711         {
712                 .procname       = "kptr_restrict",
713                 .data           = &kptr_restrict,
714                 .maxlen         = sizeof(int),
715                 .mode           = 0644,
716                 .proc_handler   = proc_dointvec_minmax,
717                 .extra1         = &zero,
718                 .extra2         = &two,
719         },
720 #endif
721         {
722                 .procname       = "ngroups_max",
723                 .data           = &ngroups_max,
724                 .maxlen         = sizeof (int),
725                 .mode           = 0444,
726                 .proc_handler   = proc_dointvec,
727         },
728 #if defined(CONFIG_LOCKUP_DETECTOR)
729         {
730                 .procname       = "watchdog",
731                 .data           = &watchdog_enabled,
732                 .maxlen         = sizeof (int),
733                 .mode           = 0644,
734                 .proc_handler   = proc_dowatchdog_enabled,
735         },
736         {
737                 .procname       = "watchdog_thresh",
738                 .data           = &softlockup_thresh,
739                 .maxlen         = sizeof(int),
740                 .mode           = 0644,
741                 .proc_handler   = proc_dowatchdog_thresh,
742                 .extra1         = &neg_one,
743                 .extra2         = &sixty,
744         },
745         {
746                 .procname       = "softlockup_panic",
747                 .data           = &softlockup_panic,
748                 .maxlen         = sizeof(int),
749                 .mode           = 0644,
750                 .proc_handler   = proc_dointvec_minmax,
751                 .extra1         = &zero,
752                 .extra2         = &one,
753         },
754         {
755                 .procname       = "nmi_watchdog",
756                 .data           = &watchdog_enabled,
757                 .maxlen         = sizeof (int),
758                 .mode           = 0644,
759                 .proc_handler   = proc_dowatchdog_enabled,
760         },
761 #endif
762 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
763         {
764                 .procname       = "unknown_nmi_panic",
765                 .data           = &unknown_nmi_panic,
766                 .maxlen         = sizeof (int),
767                 .mode           = 0644,
768                 .proc_handler   = proc_dointvec,
769         },
770 #endif
771 #if defined(CONFIG_X86)
772         {
773                 .procname       = "panic_on_unrecovered_nmi",
774                 .data           = &panic_on_unrecovered_nmi,
775                 .maxlen         = sizeof(int),
776                 .mode           = 0644,
777                 .proc_handler   = proc_dointvec,
778         },
779         {
780                 .procname       = "panic_on_io_nmi",
781                 .data           = &panic_on_io_nmi,
782                 .maxlen         = sizeof(int),
783                 .mode           = 0644,
784                 .proc_handler   = proc_dointvec,
785         },
786         {
787                 .procname       = "bootloader_type",
788                 .data           = &bootloader_type,
789                 .maxlen         = sizeof (int),
790                 .mode           = 0444,
791                 .proc_handler   = proc_dointvec,
792         },
793         {
794                 .procname       = "bootloader_version",
795                 .data           = &bootloader_version,
796                 .maxlen         = sizeof (int),
797                 .mode           = 0444,
798                 .proc_handler   = proc_dointvec,
799         },
800         {
801                 .procname       = "kstack_depth_to_print",
802                 .data           = &kstack_depth_to_print,
803                 .maxlen         = sizeof(int),
804                 .mode           = 0644,
805                 .proc_handler   = proc_dointvec,
806         },
807         {
808                 .procname       = "io_delay_type",
809                 .data           = &io_delay_type,
810                 .maxlen         = sizeof(int),
811                 .mode           = 0644,
812                 .proc_handler   = proc_dointvec,
813         },
814 #endif
815 #if defined(CONFIG_MMU)
816         {
817                 .procname       = "randomize_va_space",
818                 .data           = &randomize_va_space,
819                 .maxlen         = sizeof(int),
820                 .mode           = 0644,
821                 .proc_handler   = proc_dointvec,
822         },
823 #endif
824 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
825         {
826                 .procname       = "spin_retry",
827                 .data           = &spin_retry,
828                 .maxlen         = sizeof (int),
829                 .mode           = 0644,
830                 .proc_handler   = proc_dointvec,
831         },
832 #endif
833 #if     defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
834         {
835                 .procname       = "acpi_video_flags",
836                 .data           = &acpi_realmode_flags,
837                 .maxlen         = sizeof (unsigned long),
838                 .mode           = 0644,
839                 .proc_handler   = proc_doulongvec_minmax,
840         },
841 #endif
842 #ifdef CONFIG_IA64
843         {
844                 .procname       = "ignore-unaligned-usertrap",
845                 .data           = &no_unaligned_warning,
846                 .maxlen         = sizeof (int),
847                 .mode           = 0644,
848                 .proc_handler   = proc_dointvec,
849         },
850         {
851                 .procname       = "unaligned-dump-stack",
852                 .data           = &unaligned_dump_stack,
853                 .maxlen         = sizeof (int),
854                 .mode           = 0644,
855                 .proc_handler   = proc_dointvec,
856         },
857 #endif
858 #ifdef CONFIG_DETECT_HUNG_TASK
859         {
860                 .procname       = "hung_task_panic",
861                 .data           = &sysctl_hung_task_panic,
862                 .maxlen         = sizeof(int),
863                 .mode           = 0644,
864                 .proc_handler   = proc_dointvec_minmax,
865                 .extra1         = &zero,
866                 .extra2         = &one,
867         },
868         {
869                 .procname       = "hung_task_check_count",
870                 .data           = &sysctl_hung_task_check_count,
871                 .maxlen         = sizeof(unsigned long),
872                 .mode           = 0644,
873                 .proc_handler   = proc_doulongvec_minmax,
874         },
875         {
876                 .procname       = "hung_task_timeout_secs",
877                 .data           = &sysctl_hung_task_timeout_secs,
878                 .maxlen         = sizeof(unsigned long),
879                 .mode           = 0644,
880                 .proc_handler   = proc_dohung_task_timeout_secs,
881         },
882         {
883                 .procname       = "hung_task_warnings",
884                 .data           = &sysctl_hung_task_warnings,
885                 .maxlen         = sizeof(unsigned long),
886                 .mode           = 0644,
887                 .proc_handler   = proc_doulongvec_minmax,
888         },
889 #endif
890 #ifdef CONFIG_COMPAT
891         {
892                 .procname       = "compat-log",
893                 .data           = &compat_log,
894                 .maxlen         = sizeof (int),
895                 .mode           = 0644,
896                 .proc_handler   = proc_dointvec,
897         },
898 #endif
899 #ifdef CONFIG_RT_MUTEXES
900         {
901                 .procname       = "max_lock_depth",
902                 .data           = &max_lock_depth,
903                 .maxlen         = sizeof(int),
904                 .mode           = 0644,
905                 .proc_handler   = proc_dointvec,
906         },
907 #endif
908         {
909                 .procname       = "poweroff_cmd",
910                 .data           = &poweroff_cmd,
911                 .maxlen         = POWEROFF_CMD_PATH_LEN,
912                 .mode           = 0644,
913                 .proc_handler   = proc_dostring,
914         },
915 #ifdef CONFIG_KEYS
916         {
917                 .procname       = "keys",
918                 .mode           = 0555,
919                 .child          = key_sysctls,
920         },
921 #endif
922 #ifdef CONFIG_RCU_TORTURE_TEST
923         {
924                 .procname       = "rcutorture_runnable",
925                 .data           = &rcutorture_runnable,
926                 .maxlen         = sizeof(int),
927                 .mode           = 0644,
928                 .proc_handler   = proc_dointvec,
929         },
930 #endif
931 #ifdef CONFIG_PERF_EVENTS
932         {
933                 .procname       = "perf_event_paranoid",
934                 .data           = &sysctl_perf_event_paranoid,
935                 .maxlen         = sizeof(sysctl_perf_event_paranoid),
936                 .mode           = 0644,
937                 .proc_handler   = proc_dointvec,
938         },
939         {
940                 .procname       = "perf_event_mlock_kb",
941                 .data           = &sysctl_perf_event_mlock,
942                 .maxlen         = sizeof(sysctl_perf_event_mlock),
943                 .mode           = 0644,
944                 .proc_handler   = proc_dointvec,
945         },
946         {
947                 .procname       = "perf_event_max_sample_rate",
948                 .data           = &sysctl_perf_event_sample_rate,
949                 .maxlen         = sizeof(sysctl_perf_event_sample_rate),
950                 .mode           = 0644,
951                 .proc_handler   = proc_dointvec,
952         },
953 #endif
954 #ifdef CONFIG_KMEMCHECK
955         {
956                 .procname       = "kmemcheck",
957                 .data           = &kmemcheck_enabled,
958                 .maxlen         = sizeof(int),
959                 .mode           = 0644,
960                 .proc_handler   = proc_dointvec,
961         },
962 #endif
963 #ifdef CONFIG_BLOCK
964         {
965                 .procname       = "blk_iopoll",
966                 .data           = &blk_iopoll_enabled,
967                 .maxlen         = sizeof(int),
968                 .mode           = 0644,
969                 .proc_handler   = proc_dointvec,
970         },
971 #endif
972         { }
973 };
974
975 static struct ctl_table vm_table[] = {
976         {
977                 .procname       = "overcommit_memory",
978                 .data           = &sysctl_overcommit_memory,
979                 .maxlen         = sizeof(sysctl_overcommit_memory),
980                 .mode           = 0644,
981                 .proc_handler   = proc_dointvec,
982         },
983         {
984                 .procname       = "panic_on_oom",
985                 .data           = &sysctl_panic_on_oom,
986                 .maxlen         = sizeof(sysctl_panic_on_oom),
987                 .mode           = 0644,
988                 .proc_handler   = proc_dointvec,
989         },
990         {
991                 .procname       = "oom_kill_allocating_task",
992                 .data           = &sysctl_oom_kill_allocating_task,
993                 .maxlen         = sizeof(sysctl_oom_kill_allocating_task),
994                 .mode           = 0644,
995                 .proc_handler   = proc_dointvec,
996         },
997         {
998                 .procname       = "oom_dump_tasks",
999                 .data           = &sysctl_oom_dump_tasks,
1000                 .maxlen         = sizeof(sysctl_oom_dump_tasks),
1001                 .mode           = 0644,
1002                 .proc_handler   = proc_dointvec,
1003         },
1004         {
1005                 .procname       = "overcommit_ratio",
1006                 .data           = &sysctl_overcommit_ratio,
1007                 .maxlen         = sizeof(sysctl_overcommit_ratio),
1008                 .mode           = 0644,
1009                 .proc_handler   = proc_dointvec,
1010         },
1011         {
1012                 .procname       = "page-cluster", 
1013                 .data           = &page_cluster,
1014                 .maxlen         = sizeof(int),
1015                 .mode           = 0644,
1016                 .proc_handler   = proc_dointvec,
1017         },
1018         {
1019                 .procname       = "dirty_background_ratio",
1020                 .data           = &dirty_background_ratio,
1021                 .maxlen         = sizeof(dirty_background_ratio),
1022                 .mode           = 0644,
1023                 .proc_handler   = dirty_background_ratio_handler,
1024                 .extra1         = &zero,
1025                 .extra2         = &one_hundred,
1026         },
1027         {
1028                 .procname       = "dirty_background_bytes",
1029                 .data           = &dirty_background_bytes,
1030                 .maxlen         = sizeof(dirty_background_bytes),
1031                 .mode           = 0644,
1032                 .proc_handler   = dirty_background_bytes_handler,
1033                 .extra1         = &one_ul,
1034         },
1035         {
1036                 .procname       = "dirty_ratio",
1037                 .data           = &vm_dirty_ratio,
1038                 .maxlen         = sizeof(vm_dirty_ratio),
1039                 .mode           = 0644,
1040                 .proc_handler   = dirty_ratio_handler,
1041                 .extra1         = &zero,
1042                 .extra2         = &one_hundred,
1043         },
1044         {
1045                 .procname       = "dirty_bytes",
1046                 .data           = &vm_dirty_bytes,
1047                 .maxlen         = sizeof(vm_dirty_bytes),
1048                 .mode           = 0644,
1049                 .proc_handler   = dirty_bytes_handler,
1050                 .extra1         = &dirty_bytes_min,
1051         },
1052         {
1053                 .procname       = "dirty_writeback_centisecs",
1054                 .data           = &dirty_writeback_interval,
1055                 .maxlen         = sizeof(dirty_writeback_interval),
1056                 .mode           = 0644,
1057                 .proc_handler   = dirty_writeback_centisecs_handler,
1058         },
1059         {
1060                 .procname       = "dirty_expire_centisecs",
1061                 .data           = &dirty_expire_interval,
1062                 .maxlen         = sizeof(dirty_expire_interval),
1063                 .mode           = 0644,
1064                 .proc_handler   = proc_dointvec,
1065         },
1066         {
1067                 .procname       = "nr_pdflush_threads",
1068                 .data           = &nr_pdflush_threads,
1069                 .maxlen         = sizeof nr_pdflush_threads,
1070                 .mode           = 0444 /* read-only*/,
1071                 .proc_handler   = proc_dointvec,
1072         },
1073         {
1074                 .procname       = "swappiness",
1075                 .data           = &vm_swappiness,
1076                 .maxlen         = sizeof(vm_swappiness),
1077                 .mode           = 0644,
1078                 .proc_handler   = proc_dointvec_minmax,
1079                 .extra1         = &zero,
1080                 .extra2         = &one_hundred,
1081         },
1082 #ifdef CONFIG_HUGETLB_PAGE
1083         {
1084                 .procname       = "nr_hugepages",
1085                 .data           = NULL,
1086                 .maxlen         = sizeof(unsigned long),
1087                 .mode           = 0644,
1088                 .proc_handler   = hugetlb_sysctl_handler,
1089                 .extra1         = (void *)&hugetlb_zero,
1090                 .extra2         = (void *)&hugetlb_infinity,
1091         },
1092 #ifdef CONFIG_NUMA
1093         {
1094                 .procname       = "nr_hugepages_mempolicy",
1095                 .data           = NULL,
1096                 .maxlen         = sizeof(unsigned long),
1097                 .mode           = 0644,
1098                 .proc_handler   = &hugetlb_mempolicy_sysctl_handler,
1099                 .extra1         = (void *)&hugetlb_zero,
1100                 .extra2         = (void *)&hugetlb_infinity,
1101         },
1102 #endif
1103          {
1104                 .procname       = "hugetlb_shm_group",
1105                 .data           = &sysctl_hugetlb_shm_group,
1106                 .maxlen         = sizeof(gid_t),
1107                 .mode           = 0644,
1108                 .proc_handler   = proc_dointvec,
1109          },
1110          {
1111                 .procname       = "hugepages_treat_as_movable",
1112                 .data           = &hugepages_treat_as_movable,
1113                 .maxlen         = sizeof(int),
1114                 .mode           = 0644,
1115                 .proc_handler   = hugetlb_treat_movable_handler,
1116         },
1117         {
1118                 .procname       = "nr_overcommit_hugepages",
1119                 .data           = NULL,
1120                 .maxlen         = sizeof(unsigned long),
1121                 .mode           = 0644,
1122                 .proc_handler   = hugetlb_overcommit_handler,
1123                 .extra1         = (void *)&hugetlb_zero,
1124                 .extra2         = (void *)&hugetlb_infinity,
1125         },
1126 #endif
1127         {
1128                 .procname       = "lowmem_reserve_ratio",
1129                 .data           = &sysctl_lowmem_reserve_ratio,
1130                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
1131                 .mode           = 0644,
1132                 .proc_handler   = lowmem_reserve_ratio_sysctl_handler,
1133         },
1134         {
1135                 .procname       = "drop_caches",
1136                 .data           = &sysctl_drop_caches,
1137                 .maxlen         = sizeof(int),
1138                 .mode           = 0644,
1139                 .proc_handler   = drop_caches_sysctl_handler,
1140         },
1141 #ifdef CONFIG_COMPACTION
1142         {
1143                 .procname       = "compact_memory",
1144                 .data           = &sysctl_compact_memory,
1145                 .maxlen         = sizeof(int),
1146                 .mode           = 0200,
1147                 .proc_handler   = sysctl_compaction_handler,
1148         },
1149         {
1150                 .procname       = "extfrag_threshold",
1151                 .data           = &sysctl_extfrag_threshold,
1152                 .maxlen         = sizeof(int),
1153                 .mode           = 0644,
1154                 .proc_handler   = sysctl_extfrag_handler,
1155                 .extra1         = &min_extfrag_threshold,
1156                 .extra2         = &max_extfrag_threshold,
1157         },
1158
1159 #endif /* CONFIG_COMPACTION */
1160         {
1161                 .procname       = "min_free_kbytes",
1162                 .data           = &min_free_kbytes,
1163                 .maxlen         = sizeof(min_free_kbytes),
1164                 .mode           = 0644,
1165                 .proc_handler   = min_free_kbytes_sysctl_handler,
1166                 .extra1         = &zero,
1167         },
1168         {
1169                 .procname       = "percpu_pagelist_fraction",
1170                 .data           = &percpu_pagelist_fraction,
1171                 .maxlen         = sizeof(percpu_pagelist_fraction),
1172                 .mode           = 0644,
1173                 .proc_handler   = percpu_pagelist_fraction_sysctl_handler,
1174                 .extra1         = &min_percpu_pagelist_fract,
1175         },
1176 #ifdef CONFIG_MMU
1177         {
1178                 .procname       = "max_map_count",
1179                 .data           = &sysctl_max_map_count,
1180                 .maxlen         = sizeof(sysctl_max_map_count),
1181                 .mode           = 0644,
1182                 .proc_handler   = proc_dointvec_minmax,
1183                 .extra1         = &zero,
1184         },
1185 #else
1186         {
1187                 .procname       = "nr_trim_pages",
1188                 .data           = &sysctl_nr_trim_pages,
1189                 .maxlen         = sizeof(sysctl_nr_trim_pages),
1190                 .mode           = 0644,
1191                 .proc_handler   = proc_dointvec_minmax,
1192                 .extra1         = &zero,
1193         },
1194 #endif
1195         {
1196                 .procname       = "laptop_mode",
1197                 .data           = &laptop_mode,
1198                 .maxlen         = sizeof(laptop_mode),
1199                 .mode           = 0644,
1200                 .proc_handler   = proc_dointvec_jiffies,
1201         },
1202         {
1203                 .procname       = "block_dump",
1204                 .data           = &block_dump,
1205                 .maxlen         = sizeof(block_dump),
1206                 .mode           = 0644,
1207                 .proc_handler   = proc_dointvec,
1208                 .extra1         = &zero,
1209         },
1210         {
1211                 .procname       = "vfs_cache_pressure",
1212                 .data           = &sysctl_vfs_cache_pressure,
1213                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
1214                 .mode           = 0644,
1215                 .proc_handler   = proc_dointvec,
1216                 .extra1         = &zero,
1217         },
1218 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1219         {
1220                 .procname       = "legacy_va_layout",
1221                 .data           = &sysctl_legacy_va_layout,
1222                 .maxlen         = sizeof(sysctl_legacy_va_layout),
1223                 .mode           = 0644,
1224                 .proc_handler   = proc_dointvec,
1225                 .extra1         = &zero,
1226         },
1227 #endif
1228 #ifdef CONFIG_NUMA
1229         {
1230                 .procname       = "zone_reclaim_mode",
1231                 .data           = &zone_reclaim_mode,
1232                 .maxlen         = sizeof(zone_reclaim_mode),
1233                 .mode           = 0644,
1234                 .proc_handler   = proc_dointvec,
1235                 .extra1         = &zero,
1236         },
1237         {
1238                 .procname       = "min_unmapped_ratio",
1239                 .data           = &sysctl_min_unmapped_ratio,
1240                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
1241                 .mode           = 0644,
1242                 .proc_handler   = sysctl_min_unmapped_ratio_sysctl_handler,
1243                 .extra1         = &zero,
1244                 .extra2         = &one_hundred,
1245         },
1246         {
1247                 .procname       = "min_slab_ratio",
1248                 .data           = &sysctl_min_slab_ratio,
1249                 .maxlen         = sizeof(sysctl_min_slab_ratio),
1250                 .mode           = 0644,
1251                 .proc_handler   = sysctl_min_slab_ratio_sysctl_handler,
1252                 .extra1         = &zero,
1253                 .extra2         = &one_hundred,
1254         },
1255 #endif
1256 #ifdef CONFIG_SMP
1257         {
1258                 .procname       = "stat_interval",
1259                 .data           = &sysctl_stat_interval,
1260                 .maxlen         = sizeof(sysctl_stat_interval),
1261                 .mode           = 0644,
1262                 .proc_handler   = proc_dointvec_jiffies,
1263         },
1264 #endif
1265 #ifdef CONFIG_MMU
1266         {
1267                 .procname       = "mmap_min_addr",
1268                 .data           = &dac_mmap_min_addr,
1269                 .maxlen         = sizeof(unsigned long),
1270                 .mode           = 0644,
1271                 .proc_handler   = mmap_min_addr_handler,
1272         },
1273 #endif
1274 #ifdef CONFIG_NUMA
1275         {
1276                 .procname       = "numa_zonelist_order",
1277                 .data           = &numa_zonelist_order,
1278                 .maxlen         = NUMA_ZONELIST_ORDER_LEN,
1279                 .mode           = 0644,
1280                 .proc_handler   = numa_zonelist_order_handler,
1281         },
1282 #endif
1283 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1284    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1285         {
1286                 .procname       = "vdso_enabled",
1287                 .data           = &vdso_enabled,
1288                 .maxlen         = sizeof(vdso_enabled),
1289                 .mode           = 0644,
1290                 .proc_handler   = proc_dointvec,
1291                 .extra1         = &zero,
1292         },
1293 #endif
1294 #ifdef CONFIG_HIGHMEM
1295         {
1296                 .procname       = "highmem_is_dirtyable",
1297                 .data           = &vm_highmem_is_dirtyable,
1298                 .maxlen         = sizeof(vm_highmem_is_dirtyable),
1299                 .mode           = 0644,
1300                 .proc_handler   = proc_dointvec_minmax,
1301                 .extra1         = &zero,
1302                 .extra2         = &one,
1303         },
1304 #endif
1305         {
1306                 .procname       = "scan_unevictable_pages",
1307                 .data           = &scan_unevictable_pages,
1308                 .maxlen         = sizeof(scan_unevictable_pages),
1309                 .mode           = 0644,
1310                 .proc_handler   = scan_unevictable_handler,
1311         },
1312 #ifdef CONFIG_MEMORY_FAILURE
1313         {
1314                 .procname       = "memory_failure_early_kill",
1315                 .data           = &sysctl_memory_failure_early_kill,
1316                 .maxlen         = sizeof(sysctl_memory_failure_early_kill),
1317                 .mode           = 0644,
1318                 .proc_handler   = proc_dointvec_minmax,
1319                 .extra1         = &zero,
1320                 .extra2         = &one,
1321         },
1322         {
1323                 .procname       = "memory_failure_recovery",
1324                 .data           = &sysctl_memory_failure_recovery,
1325                 .maxlen         = sizeof(sysctl_memory_failure_recovery),
1326                 .mode           = 0644,
1327                 .proc_handler   = proc_dointvec_minmax,
1328                 .extra1         = &zero,
1329                 .extra2         = &one,
1330         },
1331 #endif
1332         { }
1333 };
1334
1335 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1336 static struct ctl_table binfmt_misc_table[] = {
1337         { }
1338 };
1339 #endif
1340
1341 static struct ctl_table fs_table[] = {
1342         {
1343                 .procname       = "inode-nr",
1344                 .data           = &inodes_stat,
1345                 .maxlen         = 2*sizeof(int),
1346                 .mode           = 0444,
1347                 .proc_handler   = proc_nr_inodes,
1348         },
1349         {
1350                 .procname       = "inode-state",
1351                 .data           = &inodes_stat,
1352                 .maxlen         = 7*sizeof(int),
1353                 .mode           = 0444,
1354                 .proc_handler   = proc_nr_inodes,
1355         },
1356         {
1357                 .procname       = "file-nr",
1358                 .data           = &files_stat,
1359                 .maxlen         = sizeof(files_stat),
1360                 .mode           = 0444,
1361                 .proc_handler   = proc_nr_files,
1362         },
1363         {
1364                 .procname       = "file-max",
1365                 .data           = &files_stat.max_files,
1366                 .maxlen         = sizeof(files_stat.max_files),
1367                 .mode           = 0644,
1368                 .proc_handler   = proc_doulongvec_minmax,
1369         },
1370         {
1371                 .procname       = "nr_open",
1372                 .data           = &sysctl_nr_open,
1373                 .maxlen         = sizeof(int),
1374                 .mode           = 0644,
1375                 .proc_handler   = proc_dointvec_minmax,
1376                 .extra1         = &sysctl_nr_open_min,
1377                 .extra2         = &sysctl_nr_open_max,
1378         },
1379         {
1380                 .procname       = "dentry-state",
1381                 .data           = &dentry_stat,
1382                 .maxlen         = 6*sizeof(int),
1383                 .mode           = 0444,
1384                 .proc_handler   = proc_nr_dentry,
1385         },
1386         {
1387                 .procname       = "overflowuid",
1388                 .data           = &fs_overflowuid,
1389                 .maxlen         = sizeof(int),
1390                 .mode           = 0644,
1391                 .proc_handler   = proc_dointvec_minmax,
1392                 .extra1         = &minolduid,
1393                 .extra2         = &maxolduid,
1394         },
1395         {
1396                 .procname       = "overflowgid",
1397                 .data           = &fs_overflowgid,
1398                 .maxlen         = sizeof(int),
1399                 .mode           = 0644,
1400                 .proc_handler   = proc_dointvec_minmax,
1401                 .extra1         = &minolduid,
1402                 .extra2         = &maxolduid,
1403         },
1404 #ifdef CONFIG_FILE_LOCKING
1405         {
1406                 .procname       = "leases-enable",
1407                 .data           = &leases_enable,
1408                 .maxlen         = sizeof(int),
1409                 .mode           = 0644,
1410                 .proc_handler   = proc_dointvec,
1411         },
1412 #endif
1413 #ifdef CONFIG_DNOTIFY
1414         {
1415                 .procname       = "dir-notify-enable",
1416                 .data           = &dir_notify_enable,
1417                 .maxlen         = sizeof(int),
1418                 .mode           = 0644,
1419                 .proc_handler   = proc_dointvec,
1420         },
1421 #endif
1422 #ifdef CONFIG_MMU
1423 #ifdef CONFIG_FILE_LOCKING
1424         {
1425                 .procname       = "lease-break-time",
1426                 .data           = &lease_break_time,
1427                 .maxlen         = sizeof(int),
1428                 .mode           = 0644,
1429                 .proc_handler   = proc_dointvec,
1430         },
1431 #endif
1432 #ifdef CONFIG_AIO
1433         {
1434                 .procname       = "aio-nr",
1435                 .data           = &aio_nr,
1436                 .maxlen         = sizeof(aio_nr),
1437                 .mode           = 0444,
1438                 .proc_handler   = proc_doulongvec_minmax,
1439         },
1440         {
1441                 .procname       = "aio-max-nr",
1442                 .data           = &aio_max_nr,
1443                 .maxlen         = sizeof(aio_max_nr),
1444                 .mode           = 0644,
1445                 .proc_handler   = proc_doulongvec_minmax,
1446         },
1447 #endif /* CONFIG_AIO */
1448 #ifdef CONFIG_INOTIFY_USER
1449         {
1450                 .procname       = "inotify",
1451                 .mode           = 0555,
1452                 .child          = inotify_table,
1453         },
1454 #endif  
1455 #ifdef CONFIG_EPOLL
1456         {
1457                 .procname       = "epoll",
1458                 .mode           = 0555,
1459                 .child          = epoll_table,
1460         },
1461 #endif
1462 #endif
1463         {
1464                 .procname       = "suid_dumpable",
1465                 .data           = &suid_dumpable,
1466                 .maxlen         = sizeof(int),
1467                 .mode           = 0644,
1468                 .proc_handler   = proc_dointvec_minmax,
1469                 .extra1         = &zero,
1470                 .extra2         = &two,
1471         },
1472 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1473         {
1474                 .procname       = "binfmt_misc",
1475                 .mode           = 0555,
1476                 .child          = binfmt_misc_table,
1477         },
1478 #endif
1479         {
1480                 .procname       = "pipe-max-size",
1481                 .data           = &pipe_max_size,
1482                 .maxlen         = sizeof(int),
1483                 .mode           = 0644,
1484                 .proc_handler   = &pipe_proc_fn,
1485                 .extra1         = &pipe_min_size,
1486         },
1487         { }
1488 };
1489
1490 static struct ctl_table debug_table[] = {
1491 #if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_SPARC) || \
1492     defined(CONFIG_S390)
1493         {
1494                 .procname       = "exception-trace",
1495                 .data           = &show_unhandled_signals,
1496                 .maxlen         = sizeof(int),
1497                 .mode           = 0644,
1498                 .proc_handler   = proc_dointvec
1499         },
1500 #endif
1501 #if defined(CONFIG_OPTPROBES)
1502         {
1503                 .procname       = "kprobes-optimization",
1504                 .data           = &sysctl_kprobes_optimization,
1505                 .maxlen         = sizeof(int),
1506                 .mode           = 0644,
1507                 .proc_handler   = proc_kprobes_optimization_handler,
1508                 .extra1         = &zero,
1509                 .extra2         = &one,
1510         },
1511 #endif
1512         { }
1513 };
1514
1515 static struct ctl_table dev_table[] = {
1516         { }
1517 };
1518
1519 static DEFINE_SPINLOCK(sysctl_lock);
1520
1521 /* called under sysctl_lock */
1522 static int use_table(struct ctl_table_header *p)
1523 {
1524         if (unlikely(p->unregistering))
1525                 return 0;
1526         p->used++;
1527         return 1;
1528 }
1529
1530 /* called under sysctl_lock */
1531 static void unuse_table(struct ctl_table_header *p)
1532 {
1533         if (!--p->used)
1534                 if (unlikely(p->unregistering))
1535                         complete(p->unregistering);
1536 }
1537
1538 /* called under sysctl_lock, will reacquire if has to wait */
1539 static void start_unregistering(struct ctl_table_header *p)
1540 {
1541         /*
1542          * if p->used is 0, nobody will ever touch that entry again;
1543          * we'll eliminate all paths to it before dropping sysctl_lock
1544          */
1545         if (unlikely(p->used)) {
1546                 struct completion wait;
1547                 init_completion(&wait);
1548                 p->unregistering = &wait;
1549                 spin_unlock(&sysctl_lock);
1550                 wait_for_completion(&wait);
1551                 spin_lock(&sysctl_lock);
1552         } else {
1553                 /* anything non-NULL; we'll never dereference it */
1554                 p->unregistering = ERR_PTR(-EINVAL);
1555         }
1556         /*
1557          * do not remove from the list until nobody holds it; walking the
1558          * list in do_sysctl() relies on that.
1559          */
1560         list_del_init(&p->ctl_entry);
1561 }
1562
1563 void sysctl_head_get(struct ctl_table_header *head)
1564 {
1565         spin_lock(&sysctl_lock);
1566         head->count++;
1567         spin_unlock(&sysctl_lock);
1568 }
1569
1570 static void free_head(struct rcu_head *rcu)
1571 {
1572         kfree(container_of(rcu, struct ctl_table_header, rcu));
1573 }
1574
1575 void sysctl_head_put(struct ctl_table_header *head)
1576 {
1577         spin_lock(&sysctl_lock);
1578         if (!--head->count)
1579                 call_rcu(&head->rcu, free_head);
1580         spin_unlock(&sysctl_lock);
1581 }
1582
1583 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1584 {
1585         if (!head)
1586                 BUG();
1587         spin_lock(&sysctl_lock);
1588         if (!use_table(head))
1589                 head = ERR_PTR(-ENOENT);
1590         spin_unlock(&sysctl_lock);
1591         return head;
1592 }
1593
1594 void sysctl_head_finish(struct ctl_table_header *head)
1595 {
1596         if (!head)
1597                 return;
1598         spin_lock(&sysctl_lock);
1599         unuse_table(head);
1600         spin_unlock(&sysctl_lock);
1601 }
1602
1603 static struct ctl_table_set *
1604 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1605 {
1606         struct ctl_table_set *set = &root->default_set;
1607         if (root->lookup)
1608                 set = root->lookup(root, namespaces);
1609         return set;
1610 }
1611
1612 static struct list_head *
1613 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1614 {
1615         struct ctl_table_set *set = lookup_header_set(root, namespaces);
1616         return &set->list;
1617 }
1618
1619 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1620                                             struct ctl_table_header *prev)
1621 {
1622         struct ctl_table_root *root;
1623         struct list_head *header_list;
1624         struct ctl_table_header *head;
1625         struct list_head *tmp;
1626
1627         spin_lock(&sysctl_lock);
1628         if (prev) {
1629                 head = prev;
1630                 tmp = &prev->ctl_entry;
1631                 unuse_table(prev);
1632                 goto next;
1633         }
1634         tmp = &root_table_header.ctl_entry;
1635         for (;;) {
1636                 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1637
1638                 if (!use_table(head))
1639                         goto next;
1640                 spin_unlock(&sysctl_lock);
1641                 return head;
1642         next:
1643                 root = head->root;
1644                 tmp = tmp->next;
1645                 header_list = lookup_header_list(root, namespaces);
1646                 if (tmp != header_list)
1647                         continue;
1648
1649                 do {
1650                         root = list_entry(root->root_list.next,
1651                                         struct ctl_table_root, root_list);
1652                         if (root == &sysctl_table_root)
1653                                 goto out;
1654                         header_list = lookup_header_list(root, namespaces);
1655                 } while (list_empty(header_list));
1656                 tmp = header_list->next;
1657         }
1658 out:
1659         spin_unlock(&sysctl_lock);
1660         return NULL;
1661 }
1662
1663 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1664 {
1665         return __sysctl_head_next(current->nsproxy, prev);
1666 }
1667
1668 void register_sysctl_root(struct ctl_table_root *root)
1669 {
1670         spin_lock(&sysctl_lock);
1671         list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1672         spin_unlock(&sysctl_lock);
1673 }
1674
1675 /*
1676  * sysctl_perm does NOT grant the superuser all rights automatically, because
1677  * some sysctl variables are readonly even to root.
1678  */
1679
1680 static int test_perm(int mode, int op)
1681 {
1682         if (!current_euid())
1683                 mode >>= 6;
1684         else if (in_egroup_p(0))
1685                 mode >>= 3;
1686         if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1687                 return 0;
1688         return -EACCES;
1689 }
1690
1691 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1692 {
1693         int error;
1694         int mode;
1695
1696         error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1697         if (error)
1698                 return error;
1699
1700         if (root->permissions)
1701                 mode = root->permissions(root, current->nsproxy, table);
1702         else
1703                 mode = table->mode;
1704
1705         return test_perm(mode, op);
1706 }
1707
1708 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1709 {
1710         for (; table->procname; table++) {
1711                 table->parent = parent;
1712                 if (table->child)
1713                         sysctl_set_parent(table, table->child);
1714         }
1715 }
1716
1717 static __init int sysctl_init(void)
1718 {
1719         sysctl_set_parent(NULL, root_table);
1720 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1721         sysctl_check_table(current->nsproxy, root_table);
1722 #endif
1723         return 0;
1724 }
1725
1726 core_initcall(sysctl_init);
1727
1728 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1729                                       struct ctl_table *table)
1730 {
1731         struct ctl_table *p;
1732         const char *s = branch->procname;
1733
1734         /* branch should have named subdirectory as its first element */
1735         if (!s || !branch->child)
1736                 return NULL;
1737
1738         /* ... and nothing else */
1739         if (branch[1].procname)
1740                 return NULL;
1741
1742         /* table should contain subdirectory with the same name */
1743         for (p = table; p->procname; p++) {
1744                 if (!p->child)
1745                         continue;
1746                 if (p->procname && strcmp(p->procname, s) == 0)
1747                         return p;
1748         }
1749         return NULL;
1750 }
1751
1752 /* see if attaching q to p would be an improvement */
1753 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1754 {
1755         struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1756         struct ctl_table *next;
1757         int is_better = 0;
1758         int not_in_parent = !p->attached_by;
1759
1760         while ((next = is_branch_in(by, to)) != NULL) {
1761                 if (by == q->attached_by)
1762                         is_better = 1;
1763                 if (to == p->attached_by)
1764                         not_in_parent = 1;
1765                 by = by->child;
1766                 to = next->child;
1767         }
1768
1769         if (is_better && not_in_parent) {
1770                 q->attached_by = by;
1771                 q->attached_to = to;
1772                 q->parent = p;
1773         }
1774 }
1775
1776 /**
1777  * __register_sysctl_paths - register a sysctl hierarchy
1778  * @root: List of sysctl headers to register on
1779  * @namespaces: Data to compute which lists of sysctl entries are visible
1780  * @path: The path to the directory the sysctl table is in.
1781  * @table: the top-level table structure
1782  *
1783  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1784  * array. A completely 0 filled entry terminates the table.
1785  *
1786  * The members of the &struct ctl_table structure are used as follows:
1787  *
1788  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1789  *            enter a sysctl file
1790  *
1791  * data - a pointer to data for use by proc_handler
1792  *
1793  * maxlen - the maximum size in bytes of the data
1794  *
1795  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1796  *
1797  * child - a pointer to the child sysctl table if this entry is a directory, or
1798  *         %NULL.
1799  *
1800  * proc_handler - the text handler routine (described below)
1801  *
1802  * de - for internal use by the sysctl routines
1803  *
1804  * extra1, extra2 - extra pointers usable by the proc handler routines
1805  *
1806  * Leaf nodes in the sysctl tree will be represented by a single file
1807  * under /proc; non-leaf nodes will be represented by directories.
1808  *
1809  * sysctl(2) can automatically manage read and write requests through
1810  * the sysctl table.  The data and maxlen fields of the ctl_table
1811  * struct enable minimal validation of the values being written to be
1812  * performed, and the mode field allows minimal authentication.
1813  *
1814  * There must be a proc_handler routine for any terminal nodes
1815  * mirrored under /proc/sys (non-terminals are handled by a built-in
1816  * directory handler).  Several default handlers are available to
1817  * cover common cases -
1818  *
1819  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1820  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(), 
1821  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1822  *
1823  * It is the handler's job to read the input buffer from user memory
1824  * and process it. The handler should return 0 on success.
1825  *
1826  * This routine returns %NULL on a failure to register, and a pointer
1827  * to the table header on success.
1828  */
1829 struct ctl_table_header *__register_sysctl_paths(
1830         struct ctl_table_root *root,
1831         struct nsproxy *namespaces,
1832         const struct ctl_path *path, struct ctl_table *table)
1833 {
1834         struct ctl_table_header *header;
1835         struct ctl_table *new, **prevp;
1836         unsigned int n, npath;
1837         struct ctl_table_set *set;
1838
1839         /* Count the path components */
1840         for (npath = 0; path[npath].procname; ++npath)
1841                 ;
1842
1843         /*
1844          * For each path component, allocate a 2-element ctl_table array.
1845          * The first array element will be filled with the sysctl entry
1846          * for this, the second will be the sentinel (procname == 0).
1847          *
1848          * We allocate everything in one go so that we don't have to
1849          * worry about freeing additional memory in unregister_sysctl_table.
1850          */
1851         header = kzalloc(sizeof(struct ctl_table_header) +
1852                          (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
1853         if (!header)
1854                 return NULL;
1855
1856         new = (struct ctl_table *) (header + 1);
1857
1858         /* Now connect the dots */
1859         prevp = &header->ctl_table;
1860         for (n = 0; n < npath; ++n, ++path) {
1861                 /* Copy the procname */
1862                 new->procname = path->procname;
1863                 new->mode     = 0555;
1864
1865                 *prevp = new;
1866                 prevp = &new->child;
1867
1868                 new += 2;
1869         }
1870         *prevp = table;
1871         header->ctl_table_arg = table;
1872
1873         INIT_LIST_HEAD(&header->ctl_entry);
1874         header->used = 0;
1875         header->unregistering = NULL;
1876         header->root = root;
1877         sysctl_set_parent(NULL, header->ctl_table);
1878         header->count = 1;
1879 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1880         if (sysctl_check_table(namespaces, header->ctl_table)) {
1881                 kfree(header);
1882                 return NULL;
1883         }
1884 #endif
1885         spin_lock(&sysctl_lock);
1886         header->set = lookup_header_set(root, namespaces);
1887         header->attached_by = header->ctl_table;
1888         header->attached_to = root_table;
1889         header->parent = &root_table_header;
1890         for (set = header->set; set; set = set->parent) {
1891                 struct ctl_table_header *p;
1892                 list_for_each_entry(p, &set->list, ctl_entry) {
1893                         if (p->unregistering)
1894                                 continue;
1895                         try_attach(p, header);
1896                 }
1897         }
1898         header->parent->count++;
1899         list_add_tail(&header->ctl_entry, &header->set->list);
1900         spin_unlock(&sysctl_lock);
1901
1902         return header;
1903 }
1904
1905 /**
1906  * register_sysctl_table_path - register a sysctl table hierarchy
1907  * @path: The path to the directory the sysctl table is in.
1908  * @table: the top-level table structure
1909  *
1910  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1911  * array. A completely 0 filled entry terminates the table.
1912  *
1913  * See __register_sysctl_paths for more details.
1914  */
1915 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1916                                                 struct ctl_table *table)
1917 {
1918         return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
1919                                         path, table);
1920 }
1921
1922 /**
1923  * register_sysctl_table - register a sysctl table hierarchy
1924  * @table: the top-level table structure
1925  *
1926  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1927  * array. A completely 0 filled entry terminates the table.
1928  *
1929  * See register_sysctl_paths for more details.
1930  */
1931 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
1932 {
1933         static const struct ctl_path null_path[] = { {} };
1934
1935         return register_sysctl_paths(null_path, table);
1936 }
1937
1938 /**
1939  * unregister_sysctl_table - unregister a sysctl table hierarchy
1940  * @header: the header returned from register_sysctl_table
1941  *
1942  * Unregisters the sysctl table and all children. proc entries may not
1943  * actually be removed until they are no longer used by anyone.
1944  */
1945 void unregister_sysctl_table(struct ctl_table_header * header)
1946 {
1947         might_sleep();
1948
1949         if (header == NULL)
1950                 return;
1951
1952         spin_lock(&sysctl_lock);
1953         start_unregistering(header);
1954         if (!--header->parent->count) {
1955                 WARN_ON(1);
1956                 call_rcu(&header->parent->rcu, free_head);
1957         }
1958         if (!--header->count)
1959                 call_rcu(&header->rcu, free_head);
1960         spin_unlock(&sysctl_lock);
1961 }
1962
1963 int sysctl_is_seen(struct ctl_table_header *p)
1964 {
1965         struct ctl_table_set *set = p->set;
1966         int res;
1967         spin_lock(&sysctl_lock);
1968         if (p->unregistering)
1969                 res = 0;
1970         else if (!set->is_seen)
1971                 res = 1;
1972         else
1973                 res = set->is_seen(set);
1974         spin_unlock(&sysctl_lock);
1975         return res;
1976 }
1977
1978 void setup_sysctl_set(struct ctl_table_set *p,
1979         struct ctl_table_set *parent,
1980         int (*is_seen)(struct ctl_table_set *))
1981 {
1982         INIT_LIST_HEAD(&p->list);
1983         p->parent = parent ? parent : &sysctl_table_root.default_set;
1984         p->is_seen = is_seen;
1985 }
1986
1987 #else /* !CONFIG_SYSCTL */
1988 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
1989 {
1990         return NULL;
1991 }
1992
1993 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1994                                                     struct ctl_table *table)
1995 {
1996         return NULL;
1997 }
1998
1999 void unregister_sysctl_table(struct ctl_table_header * table)
2000 {
2001 }
2002
2003 void setup_sysctl_set(struct ctl_table_set *p,
2004         struct ctl_table_set *parent,
2005         int (*is_seen)(struct ctl_table_set *))
2006 {
2007 }
2008
2009 void sysctl_head_put(struct ctl_table_header *head)
2010 {
2011 }
2012
2013 #endif /* CONFIG_SYSCTL */
2014
2015 /*
2016  * /proc/sys support
2017  */
2018
2019 #ifdef CONFIG_PROC_SYSCTL
2020
2021 static int _proc_do_string(void* data, int maxlen, int write,
2022                            void __user *buffer,
2023                            size_t *lenp, loff_t *ppos)
2024 {
2025         size_t len;
2026         char __user *p;
2027         char c;
2028
2029         if (!data || !maxlen || !*lenp) {
2030                 *lenp = 0;
2031                 return 0;
2032         }
2033
2034         if (write) {
2035                 len = 0;
2036                 p = buffer;
2037                 while (len < *lenp) {
2038                         if (get_user(c, p++))
2039                                 return -EFAULT;
2040                         if (c == 0 || c == '\n')
2041                                 break;
2042                         len++;
2043                 }
2044                 if (len >= maxlen)
2045                         len = maxlen-1;
2046                 if(copy_from_user(data, buffer, len))
2047                         return -EFAULT;
2048                 ((char *) data)[len] = 0;
2049                 *ppos += *lenp;
2050         } else {
2051                 len = strlen(data);
2052                 if (len > maxlen)
2053                         len = maxlen;
2054
2055                 if (*ppos > len) {
2056                         *lenp = 0;
2057                         return 0;
2058                 }
2059
2060                 data += *ppos;
2061                 len  -= *ppos;
2062
2063                 if (len > *lenp)
2064                         len = *lenp;
2065                 if (len)
2066                         if(copy_to_user(buffer, data, len))
2067                                 return -EFAULT;
2068                 if (len < *lenp) {
2069                         if(put_user('\n', ((char __user *) buffer) + len))
2070                                 return -EFAULT;
2071                         len++;
2072                 }
2073                 *lenp = len;
2074                 *ppos += len;
2075         }
2076         return 0;
2077 }
2078
2079 /**
2080  * proc_dostring - read a string sysctl
2081  * @table: the sysctl table
2082  * @write: %TRUE if this is a write to the sysctl file
2083  * @buffer: the user buffer
2084  * @lenp: the size of the user buffer
2085  * @ppos: file position
2086  *
2087  * Reads/writes a string from/to the user buffer. If the kernel
2088  * buffer provided is not large enough to hold the string, the
2089  * string is truncated. The copied string is %NULL-terminated.
2090  * If the string is being read by the user process, it is copied
2091  * and a newline '\n' is added. It is truncated if the buffer is
2092  * not large enough.
2093  *
2094  * Returns 0 on success.
2095  */
2096 int proc_dostring(struct ctl_table *table, int write,
2097                   void __user *buffer, size_t *lenp, loff_t *ppos)
2098 {
2099         return _proc_do_string(table->data, table->maxlen, write,
2100                                buffer, lenp, ppos);
2101 }
2102
2103 static size_t proc_skip_spaces(char **buf)
2104 {
2105         size_t ret;
2106         char *tmp = skip_spaces(*buf);
2107         ret = tmp - *buf;
2108         *buf = tmp;
2109         return ret;
2110 }
2111
2112 static void proc_skip_char(char **buf, size_t *size, const char v)
2113 {
2114         while (*size) {
2115                 if (**buf != v)
2116                         break;
2117                 (*size)--;
2118                 (*buf)++;
2119         }
2120 }
2121
2122 #define TMPBUFLEN 22
2123 /**
2124  * proc_get_long - reads an ASCII formatted integer from a user buffer
2125  *
2126  * @buf: a kernel buffer
2127  * @size: size of the kernel buffer
2128  * @val: this is where the number will be stored
2129  * @neg: set to %TRUE if number is negative
2130  * @perm_tr: a vector which contains the allowed trailers
2131  * @perm_tr_len: size of the perm_tr vector
2132  * @tr: pointer to store the trailer character
2133  *
2134  * In case of success %0 is returned and @buf and @size are updated with
2135  * the amount of bytes read. If @tr is non-NULL and a trailing
2136  * character exists (size is non-zero after returning from this
2137  * function), @tr is updated with the trailing character.
2138  */
2139 static int proc_get_long(char **buf, size_t *size,
2140                           unsigned long *val, bool *neg,
2141                           const char *perm_tr, unsigned perm_tr_len, char *tr)
2142 {
2143         int len;
2144         char *p, tmp[TMPBUFLEN];
2145
2146         if (!*size)
2147                 return -EINVAL;
2148
2149         len = *size;
2150         if (len > TMPBUFLEN - 1)
2151                 len = TMPBUFLEN - 1;
2152
2153         memcpy(tmp, *buf, len);
2154
2155         tmp[len] = 0;
2156         p = tmp;
2157         if (*p == '-' && *size > 1) {
2158                 *neg = true;
2159                 p++;
2160         } else
2161                 *neg = false;
2162         if (!isdigit(*p))
2163                 return -EINVAL;
2164
2165         *val = simple_strtoul(p, &p, 0);
2166
2167         len = p - tmp;
2168
2169         /* We don't know if the next char is whitespace thus we may accept
2170          * invalid integers (e.g. 1234...a) or two integers instead of one
2171          * (e.g. 123...1). So lets not allow such large numbers. */
2172         if (len == TMPBUFLEN - 1)
2173                 return -EINVAL;
2174
2175         if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
2176                 return -EINVAL;
2177
2178         if (tr && (len < *size))
2179                 *tr = *p;
2180
2181         *buf += len;
2182         *size -= len;
2183
2184         return 0;
2185 }
2186
2187 /**
2188  * proc_put_long - converts an integer to a decimal ASCII formatted string
2189  *
2190  * @buf: the user buffer
2191  * @size: the size of the user buffer
2192  * @val: the integer to be converted
2193  * @neg: sign of the number, %TRUE for negative
2194  *
2195  * In case of success %0 is returned and @buf and @size are updated with
2196  * the amount of bytes written.
2197  */
2198 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2199                           bool neg)
2200 {
2201         int len;
2202         char tmp[TMPBUFLEN], *p = tmp;
2203
2204         sprintf(p, "%s%lu", neg ? "-" : "", val);
2205         len = strlen(tmp);
2206         if (len > *size)
2207                 len = *size;
2208         if (copy_to_user(*buf, tmp, len))
2209                 return -EFAULT;
2210         *size -= len;
2211         *buf += len;
2212         return 0;
2213 }
2214 #undef TMPBUFLEN
2215
2216 static int proc_put_char(void __user **buf, size_t *size, char c)
2217 {
2218         if (*size) {
2219                 char __user **buffer = (char __user **)buf;
2220                 if (put_user(c, *buffer))
2221                         return -EFAULT;
2222                 (*size)--, (*buffer)++;
2223                 *buf = *buffer;
2224         }
2225         return 0;
2226 }
2227
2228 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
2229                                  int *valp,
2230                                  int write, void *data)
2231 {
2232         if (write) {
2233                 *valp = *negp ? -*lvalp : *lvalp;
2234         } else {
2235                 int val = *valp;
2236                 if (val < 0) {
2237                         *negp = true;
2238                         *lvalp = (unsigned long)-val;
2239                 } else {
2240                         *negp = false;
2241                         *lvalp = (unsigned long)val;
2242                 }
2243         }
2244         return 0;
2245 }
2246
2247 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2248
2249 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2250                   int write, void __user *buffer,
2251                   size_t *lenp, loff_t *ppos,
2252                   int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2253                               int write, void *data),
2254                   void *data)
2255 {
2256         int *i, vleft, first = 1, err = 0;
2257         unsigned long page = 0;
2258         size_t left;
2259         char *kbuf;
2260         
2261         if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2262                 *lenp = 0;
2263                 return 0;
2264         }
2265         
2266         i = (int *) tbl_data;
2267         vleft = table->maxlen / sizeof(*i);
2268         left = *lenp;
2269
2270         if (!conv)
2271                 conv = do_proc_dointvec_conv;
2272
2273         if (write) {
2274                 if (left > PAGE_SIZE - 1)
2275                         left = PAGE_SIZE - 1;
2276                 page = __get_free_page(GFP_TEMPORARY);
2277                 kbuf = (char *) page;
2278                 if (!kbuf)
2279                         return -ENOMEM;
2280                 if (copy_from_user(kbuf, buffer, left)) {
2281                         err = -EFAULT;
2282                         goto free;
2283                 }
2284                 kbuf[left] = 0;
2285         }
2286
2287         for (; left && vleft--; i++, first=0) {
2288                 unsigned long lval;
2289                 bool neg;
2290
2291                 if (write) {
2292                         left -= proc_skip_spaces(&kbuf);
2293
2294                         if (!left)
2295                                 break;
2296                         err = proc_get_long(&kbuf, &left, &lval, &neg,
2297                                              proc_wspace_sep,
2298                                              sizeof(proc_wspace_sep), NULL);
2299                         if (err)
2300                                 break;
2301                         if (conv(&neg, &lval, i, 1, data)) {
2302                                 err = -EINVAL;
2303                                 break;
2304                         }
2305                 } else {
2306                         if (conv(&neg, &lval, i, 0, data)) {
2307                                 err = -EINVAL;
2308                                 break;
2309                         }
2310                         if (!first)
2311                                 err = proc_put_char(&buffer, &left, '\t');
2312                         if (err)
2313                                 break;
2314                         err = proc_put_long(&buffer, &left, lval, neg);
2315                         if (err)
2316                                 break;
2317                 }
2318         }
2319
2320         if (!write && !first && left && !err)
2321                 err = proc_put_char(&buffer, &left, '\n');
2322         if (write && !err && left)
2323                 left -= proc_skip_spaces(&kbuf);
2324 free:
2325         if (write) {
2326                 free_page(page);
2327                 if (first)
2328                         return err ? : -EINVAL;
2329         }
2330         *lenp -= left;
2331         *ppos += *lenp;
2332         return err;
2333 }
2334
2335 static int do_proc_dointvec(struct ctl_table *table, int write,
2336                   void __user *buffer, size_t *lenp, loff_t *ppos,
2337                   int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2338                               int write, void *data),
2339                   void *data)
2340 {
2341         return __do_proc_dointvec(table->data, table, write,
2342                         buffer, lenp, ppos, conv, data);
2343 }
2344
2345 /**
2346  * proc_dointvec - read a vector of integers
2347  * @table: the sysctl table
2348  * @write: %TRUE if this is a write to the sysctl file
2349  * @buffer: the user buffer
2350  * @lenp: the size of the user buffer
2351  * @ppos: file position
2352  *
2353  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2354  * values from/to the user buffer, treated as an ASCII string. 
2355  *
2356  * Returns 0 on success.
2357  */
2358 int proc_dointvec(struct ctl_table *table, int write,
2359                      void __user *buffer, size_t *lenp, loff_t *ppos)
2360 {
2361     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2362                             NULL,NULL);
2363 }
2364
2365 /*
2366  * Taint values can only be increased
2367  * This means we can safely use a temporary.
2368  */
2369 static int proc_taint(struct ctl_table *table, int write,
2370                                void __user *buffer, size_t *lenp, loff_t *ppos)
2371 {
2372         struct ctl_table t;
2373         unsigned long tmptaint = get_taint();
2374         int err;
2375
2376         if (write && !capable(CAP_SYS_ADMIN))
2377                 return -EPERM;
2378
2379         t = *table;
2380         t.data = &tmptaint;
2381         err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2382         if (err < 0)
2383                 return err;
2384
2385         if (write) {
2386                 /*
2387                  * Poor man's atomic or. Not worth adding a primitive
2388                  * to everyone's atomic.h for this
2389                  */
2390                 int i;
2391                 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2392                         if ((tmptaint >> i) & 1)
2393                                 add_taint(i);
2394                 }
2395         }
2396
2397         return err;
2398 }
2399
2400 struct do_proc_dointvec_minmax_conv_param {
2401         int *min;
2402         int *max;
2403 };
2404
2405 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2406                                         int *valp,
2407                                         int write, void *data)
2408 {
2409         struct do_proc_dointvec_minmax_conv_param *param = data;
2410         if (write) {
2411                 int val = *negp ? -*lvalp : *lvalp;
2412                 if ((param->min && *param->min > val) ||
2413                     (param->max && *param->max < val))
2414                         return -EINVAL;
2415                 *valp = val;
2416         } else {
2417                 int val = *valp;
2418                 if (val < 0) {
2419                         *negp = true;
2420                         *lvalp = (unsigned long)-val;
2421                 } else {
2422                         *negp = false;
2423                         *lvalp = (unsigned long)val;
2424                 }
2425         }
2426         return 0;
2427 }
2428
2429 /**
2430  * proc_dointvec_minmax - read a vector of integers with min/max values
2431  * @table: the sysctl table
2432  * @write: %TRUE if this is a write to the sysctl file
2433  * @buffer: the user buffer
2434  * @lenp: the size of the user buffer
2435  * @ppos: file position
2436  *
2437  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2438  * values from/to the user buffer, treated as an ASCII string.
2439  *
2440  * This routine will ensure the values are within the range specified by
2441  * table->extra1 (min) and table->extra2 (max).
2442  *
2443  * Returns 0 on success.
2444  */
2445 int proc_dointvec_minmax(struct ctl_table *table, int write,
2446                   void __user *buffer, size_t *lenp, loff_t *ppos)
2447 {
2448         struct do_proc_dointvec_minmax_conv_param param = {
2449                 .min = (int *) table->extra1,
2450                 .max = (int *) table->extra2,
2451         };
2452         return do_proc_dointvec(table, write, buffer, lenp, ppos,
2453                                 do_proc_dointvec_minmax_conv, &param);
2454 }
2455
2456 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2457                                      void __user *buffer,
2458                                      size_t *lenp, loff_t *ppos,
2459                                      unsigned long convmul,
2460                                      unsigned long convdiv)
2461 {
2462         unsigned long *i, *min, *max;
2463         int vleft, first = 1, err = 0;
2464         unsigned long page = 0;
2465         size_t left;
2466         char *kbuf;
2467
2468         if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2469                 *lenp = 0;
2470                 return 0;
2471         }
2472
2473         i = (unsigned long *) data;
2474         min = (unsigned long *) table->extra1;
2475         max = (unsigned long *) table->extra2;
2476         vleft = table->maxlen / sizeof(unsigned long);
2477         left = *lenp;
2478
2479         if (write) {
2480                 if (left > PAGE_SIZE - 1)
2481                         left = PAGE_SIZE - 1;
2482                 page = __get_free_page(GFP_TEMPORARY);
2483                 kbuf = (char *) page;
2484                 if (!kbuf)
2485                         return -ENOMEM;
2486                 if (copy_from_user(kbuf, buffer, left)) {
2487                         err = -EFAULT;
2488                         goto free;
2489                 }
2490                 kbuf[left] = 0;
2491         }
2492
2493         for (; left && vleft--; i++, first = 0) {
2494                 unsigned long val;
2495
2496                 if (write) {
2497                         bool neg;
2498
2499                         left -= proc_skip_spaces(&kbuf);
2500
2501                         err = proc_get_long(&kbuf, &left, &val, &neg,
2502                                              proc_wspace_sep,
2503                                              sizeof(proc_wspace_sep), NULL);
2504                         if (err)
2505                                 break;
2506                         if (neg)
2507                                 continue;
2508                         if ((min && val < *min) || (max && val > *max))
2509                                 continue;
2510                         *i = val;
2511                 } else {
2512                         val = convdiv * (*i) / convmul;
2513                         if (!first)
2514                                 err = proc_put_char(&buffer, &left, '\t');
2515                         err = proc_put_long(&buffer, &left, val, false);
2516                         if (err)
2517                                 break;
2518                 }
2519         }
2520
2521         if (!write && !first && left && !err)
2522                 err = proc_put_char(&buffer, &left, '\n');
2523         if (write && !err)
2524                 left -= proc_skip_spaces(&kbuf);
2525 free:
2526         if (write) {
2527                 free_page(page);
2528                 if (first)
2529                         return err ? : -EINVAL;
2530         }
2531         *lenp -= left;
2532         *ppos += *lenp;
2533         return err;
2534 }
2535
2536 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2537                                      void __user *buffer,
2538                                      size_t *lenp, loff_t *ppos,
2539                                      unsigned long convmul,
2540                                      unsigned long convdiv)
2541 {
2542         return __do_proc_doulongvec_minmax(table->data, table, write,
2543                         buffer, lenp, ppos, convmul, convdiv);
2544 }
2545
2546 /**
2547  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2548  * @table: the sysctl table
2549  * @write: %TRUE if this is a write to the sysctl file
2550  * @buffer: the user buffer
2551  * @lenp: the size of the user buffer
2552  * @ppos: file position
2553  *
2554  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2555  * values from/to the user buffer, treated as an ASCII string.
2556  *
2557  * This routine will ensure the values are within the range specified by
2558  * table->extra1 (min) and table->extra2 (max).
2559  *
2560  * Returns 0 on success.
2561  */
2562 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2563                            void __user *buffer, size_t *lenp, loff_t *ppos)
2564 {
2565     return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2566 }
2567
2568 /**
2569  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2570  * @table: the sysctl table
2571  * @write: %TRUE if this is a write to the sysctl file
2572  * @buffer: the user buffer
2573  * @lenp: the size of the user buffer
2574  * @ppos: file position
2575  *
2576  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2577  * values from/to the user buffer, treated as an ASCII string. The values
2578  * are treated as milliseconds, and converted to jiffies when they are stored.
2579  *
2580  * This routine will ensure the values are within the range specified by
2581  * table->extra1 (min) and table->extra2 (max).
2582  *
2583  * Returns 0 on success.
2584  */
2585 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2586                                       void __user *buffer,
2587                                       size_t *lenp, loff_t *ppos)
2588 {
2589     return do_proc_doulongvec_minmax(table, write, buffer,
2590                                      lenp, ppos, HZ, 1000l);
2591 }
2592
2593
2594 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2595                                          int *valp,
2596                                          int write, void *data)
2597 {
2598         if (write) {
2599                 if (*lvalp > LONG_MAX / HZ)
2600                         return 1;
2601                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2602         } else {
2603                 int val = *valp;
2604                 unsigned long lval;
2605                 if (val < 0) {
2606                         *negp = true;
2607                         lval = (unsigned long)-val;
2608                 } else {
2609                         *negp = false;
2610                         lval = (unsigned long)val;
2611                 }
2612                 *lvalp = lval / HZ;
2613         }
2614         return 0;
2615 }
2616
2617 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
2618                                                 int *valp,
2619                                                 int write, void *data)
2620 {
2621         if (write) {
2622                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2623                         return 1;
2624                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2625         } else {
2626                 int val = *valp;
2627                 unsigned long lval;
2628                 if (val < 0) {
2629                         *negp = true;
2630                         lval = (unsigned long)-val;
2631                 } else {
2632                         *negp = false;
2633                         lval = (unsigned long)val;
2634                 }
2635                 *lvalp = jiffies_to_clock_t(lval);
2636         }
2637         return 0;
2638 }
2639
2640 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
2641                                             int *valp,
2642                                             int write, void *data)
2643 {
2644         if (write) {
2645                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2646         } else {
2647                 int val = *valp;
2648                 unsigned long lval;
2649                 if (val < 0) {
2650                         *negp = true;
2651                         lval = (unsigned long)-val;
2652                 } else {
2653                         *negp = false;
2654                         lval = (unsigned long)val;
2655                 }
2656                 *lvalp = jiffies_to_msecs(lval);
2657         }
2658         return 0;
2659 }
2660
2661 /**
2662  * proc_dointvec_jiffies - read a vector of integers as seconds
2663  * @table: the sysctl table
2664  * @write: %TRUE if this is a write to the sysctl file
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 int) integer
2670  * values from/to the user buffer, treated as an ASCII string. 
2671  * The values read are assumed to be in seconds, and are converted into
2672  * jiffies.
2673  *
2674  * Returns 0 on success.
2675  */
2676 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2677                           void __user *buffer, size_t *lenp, loff_t *ppos)
2678 {
2679     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2680                             do_proc_dointvec_jiffies_conv,NULL);
2681 }
2682
2683 /**
2684  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2685  * @table: the sysctl table
2686  * @write: %TRUE if this is a write to the sysctl file
2687  * @buffer: the user buffer
2688  * @lenp: the size of the user buffer
2689  * @ppos: pointer to the file position
2690  *
2691  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2692  * values from/to the user buffer, treated as an ASCII string. 
2693  * The values read are assumed to be in 1/USER_HZ seconds, and 
2694  * are converted into jiffies.
2695  *
2696  * Returns 0 on success.
2697  */
2698 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2699                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2700 {
2701     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2702                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2703 }
2704
2705 /**
2706  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2707  * @table: the sysctl table
2708  * @write: %TRUE if this is a write to the sysctl file
2709  * @buffer: the user buffer
2710  * @lenp: the size of the user buffer
2711  * @ppos: file position
2712  * @ppos: the current position in the file
2713  *
2714  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2715  * values from/to the user buffer, treated as an ASCII string. 
2716  * The values read are assumed to be in 1/1000 seconds, and 
2717  * are converted into jiffies.
2718  *
2719  * Returns 0 on success.
2720  */
2721 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2722                              void __user *buffer, size_t *lenp, loff_t *ppos)
2723 {
2724         return do_proc_dointvec(table, write, buffer, lenp, ppos,
2725                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2726 }
2727
2728 static int proc_do_cad_pid(struct ctl_table *table, int write,
2729                            void __user *buffer, size_t *lenp, loff_t *ppos)
2730 {
2731         struct pid *new_pid;
2732         pid_t tmp;
2733         int r;
2734
2735         tmp = pid_vnr(cad_pid);
2736
2737         r = __do_proc_dointvec(&tmp, table, write, buffer,
2738                                lenp, ppos, NULL, NULL);
2739         if (r || !write)
2740                 return r;
2741
2742         new_pid = find_get_pid(tmp);
2743         if (!new_pid)
2744                 return -ESRCH;
2745
2746         put_pid(xchg(&cad_pid, new_pid));
2747         return 0;
2748 }
2749
2750 /**
2751  * proc_do_large_bitmap - read/write from/to a large bitmap
2752  * @table: the sysctl table
2753  * @write: %TRUE if this is a write to the sysctl file
2754  * @buffer: the user buffer
2755  * @lenp: the size of the user buffer
2756  * @ppos: file position
2757  *
2758  * The bitmap is stored at table->data and the bitmap length (in bits)
2759  * in table->maxlen.
2760  *
2761  * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2762  * large bitmaps may be represented in a compact manner. Writing into
2763  * the file will clear the bitmap then update it with the given input.
2764  *
2765  * Returns 0 on success.
2766  */
2767 int proc_do_large_bitmap(struct ctl_table *table, int write,
2768                          void __user *buffer, size_t *lenp, loff_t *ppos)
2769 {
2770         int err = 0;
2771         bool first = 1;
2772         size_t left = *lenp;
2773         unsigned long bitmap_len = table->maxlen;
2774         unsigned long *bitmap = (unsigned long *) table->data;
2775         unsigned long *tmp_bitmap = NULL;
2776         char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
2777
2778         if (!bitmap_len || !left || (*ppos && !write)) {
2779                 *lenp = 0;
2780                 return 0;
2781         }
2782
2783         if (write) {
2784                 unsigned long page = 0;
2785                 char *kbuf;
2786
2787                 if (left > PAGE_SIZE - 1)
2788                         left = PAGE_SIZE - 1;
2789
2790                 page = __get_free_page(GFP_TEMPORARY);
2791                 kbuf = (char *) page;
2792                 if (!kbuf)
2793                         return -ENOMEM;
2794                 if (copy_from_user(kbuf, buffer, left)) {
2795                         free_page(page);
2796                         return -EFAULT;
2797                 }
2798                 kbuf[left] = 0;
2799
2800                 tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
2801                                      GFP_KERNEL);
2802                 if (!tmp_bitmap) {
2803                         free_page(page);
2804                         return -ENOMEM;
2805                 }
2806                 proc_skip_char(&kbuf, &left, '\n');
2807                 while (!err && left) {
2808                         unsigned long val_a, val_b;
2809                         bool neg;
2810
2811                         err = proc_get_long(&kbuf, &left, &val_a, &neg, tr_a,
2812                                              sizeof(tr_a), &c);
2813                         if (err)
2814                                 break;
2815                         if (val_a >= bitmap_len || neg) {
2816                                 err = -EINVAL;
2817                                 break;
2818                         }
2819
2820                         val_b = val_a;
2821                         if (left) {
2822                                 kbuf++;
2823                                 left--;
2824                         }
2825
2826                         if (c == '-') {
2827                                 err = proc_get_long(&kbuf, &left, &val_b,
2828                                                      &neg, tr_b, sizeof(tr_b),
2829                                                      &c);
2830                                 if (err)
2831                                         break;
2832                                 if (val_b >= bitmap_len || neg ||
2833                                     val_a > val_b) {
2834                                         err = -EINVAL;
2835                                         break;
2836                                 }
2837                                 if (left) {
2838                                         kbuf++;
2839                                         left--;
2840                                 }
2841                         }
2842
2843                         while (val_a <= val_b)
2844                                 set_bit(val_a++, tmp_bitmap);
2845
2846                         first = 0;
2847                         proc_skip_char(&kbuf, &left, '\n');
2848                 }
2849                 free_page(page);
2850         } else {
2851                 unsigned long bit_a, bit_b = 0;
2852
2853                 while (left) {
2854                         bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
2855                         if (bit_a >= bitmap_len)
2856                                 break;
2857                         bit_b = find_next_zero_bit(bitmap, bitmap_len,
2858                                                    bit_a + 1) - 1;
2859
2860                         if (!first) {
2861                                 err = proc_put_char(&buffer, &left, ',');
2862                                 if (err)
2863                                         break;
2864                         }
2865                         err = proc_put_long(&buffer, &left, bit_a, false);
2866                         if (err)
2867                                 break;
2868                         if (bit_a != bit_b) {
2869                                 err = proc_put_char(&buffer, &left, '-');
2870                                 if (err)
2871                                         break;
2872                                 err = proc_put_long(&buffer, &left, bit_b, false);
2873                                 if (err)
2874                                         break;
2875                         }
2876
2877                         first = 0; bit_b++;
2878                 }
2879                 if (!err)
2880                         err = proc_put_char(&buffer, &left, '\n');
2881         }
2882
2883         if (!err) {
2884                 if (write) {
2885                         if (*ppos)
2886                                 bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
2887                         else
2888                                 memcpy(bitmap, tmp_bitmap,
2889                                         BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long));
2890                 }
2891                 kfree(tmp_bitmap);
2892                 *lenp -= left;
2893                 *ppos += *lenp;
2894                 return 0;
2895         } else {
2896                 kfree(tmp_bitmap);
2897                 return err;
2898         }
2899 }
2900
2901 #else /* CONFIG_PROC_SYSCTL */
2902
2903 int proc_dostring(struct ctl_table *table, int write,
2904                   void __user *buffer, size_t *lenp, loff_t *ppos)
2905 {
2906         return -ENOSYS;
2907 }
2908
2909 int proc_dointvec(struct ctl_table *table, int write,
2910                   void __user *buffer, size_t *lenp, loff_t *ppos)
2911 {
2912         return -ENOSYS;
2913 }
2914
2915 int proc_dointvec_minmax(struct ctl_table *table, int write,
2916                     void __user *buffer, size_t *lenp, loff_t *ppos)
2917 {
2918         return -ENOSYS;
2919 }
2920
2921 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2922                     void __user *buffer, size_t *lenp, loff_t *ppos)
2923 {
2924         return -ENOSYS;
2925 }
2926
2927 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2928                     void __user *buffer, size_t *lenp, loff_t *ppos)
2929 {
2930         return -ENOSYS;
2931 }
2932
2933 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2934                              void __user *buffer, size_t *lenp, loff_t *ppos)
2935 {
2936         return -ENOSYS;
2937 }
2938
2939 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2940                     void __user *buffer, size_t *lenp, loff_t *ppos)
2941 {
2942         return -ENOSYS;
2943 }
2944
2945 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2946                                       void __user *buffer,
2947                                       size_t *lenp, loff_t *ppos)
2948 {
2949     return -ENOSYS;
2950 }
2951
2952
2953 #endif /* CONFIG_PROC_SYSCTL */
2954
2955 /*
2956  * No sense putting this after each symbol definition, twice,
2957  * exception granted :-)
2958  */
2959 EXPORT_SYMBOL(proc_dointvec);
2960 EXPORT_SYMBOL(proc_dointvec_jiffies);
2961 EXPORT_SYMBOL(proc_dointvec_minmax);
2962 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2963 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2964 EXPORT_SYMBOL(proc_dostring);
2965 EXPORT_SYMBOL(proc_doulongvec_minmax);
2966 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2967 EXPORT_SYMBOL(register_sysctl_table);
2968 EXPORT_SYMBOL(register_sysctl_paths);
2969 EXPORT_SYMBOL(unregister_sysctl_table);