[PATCH] sysctl: move SYSV IPC sysctls to their own file
[linux-3.10.git] / kernel / sysctl.c
1 /*
2  * sysctl.c: General linux system control interface
3  *
4  * Begun 24 March 1995, Stephen Tweedie
5  * Added /proc support, Dec 1995
6  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
7  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
8  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
9  * Dynamic registration fixes, Stephen Tweedie.
10  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
11  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
12  *  Horn.
13  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
14  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
15  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
16  *  Wendling.
17  * The list_for_each() macro wasn't appropriate for the sysctl loop.
18  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
19  */
20
21 #include <linux/module.h>
22 #include <linux/mm.h>
23 #include <linux/swap.h>
24 #include <linux/slab.h>
25 #include <linux/sysctl.h>
26 #include <linux/proc_fs.h>
27 #include <linux/capability.h>
28 #include <linux/ctype.h>
29 #include <linux/utsname.h>
30 #include <linux/capability.h>
31 #include <linux/smp_lock.h>
32 #include <linux/init.h>
33 #include <linux/kernel.h>
34 #include <linux/kobject.h>
35 #include <linux/net.h>
36 #include <linux/sysrq.h>
37 #include <linux/highuid.h>
38 #include <linux/writeback.h>
39 #include <linux/hugetlb.h>
40 #include <linux/security.h>
41 #include <linux/initrd.h>
42 #include <linux/times.h>
43 #include <linux/limits.h>
44 #include <linux/dcache.h>
45 #include <linux/syscalls.h>
46 #include <linux/nfs_fs.h>
47 #include <linux/acpi.h>
48
49 #include <asm/uaccess.h>
50 #include <asm/processor.h>
51
52 extern int proc_nr_files(ctl_table *table, int write, struct file *filp,
53                      void __user *buffer, size_t *lenp, loff_t *ppos);
54
55 #ifdef CONFIG_X86
56 #include <asm/nmi.h>
57 #include <asm/stacktrace.h>
58 #endif
59
60 #if defined(CONFIG_SYSCTL)
61
62 /* External variables not in a header file. */
63 extern int C_A_D;
64 extern int sysctl_overcommit_memory;
65 extern int sysctl_overcommit_ratio;
66 extern int sysctl_panic_on_oom;
67 extern int max_threads;
68 extern int core_uses_pid;
69 extern int suid_dumpable;
70 extern char core_pattern[];
71 extern int pid_max;
72 extern int min_free_kbytes;
73 extern int printk_ratelimit_jiffies;
74 extern int printk_ratelimit_burst;
75 extern int pid_max_min, pid_max_max;
76 extern int sysctl_drop_caches;
77 extern int percpu_pagelist_fraction;
78 extern int compat_log;
79
80 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
81 static int maxolduid = 65535;
82 static int minolduid;
83 static int min_percpu_pagelist_fract = 8;
84
85 static int ngroups_max = NGROUPS_MAX;
86
87 #ifdef CONFIG_KMOD
88 extern char modprobe_path[];
89 #endif
90 #ifdef CONFIG_CHR_DEV_SG
91 extern int sg_big_buff;
92 #endif
93
94 #ifdef __sparc__
95 extern char reboot_command [];
96 extern int stop_a_enabled;
97 extern int scons_pwroff;
98 #endif
99
100 #ifdef __hppa__
101 extern int pwrsw_enabled;
102 extern int unaligned_enabled;
103 #endif
104
105 #ifdef CONFIG_S390
106 #ifdef CONFIG_MATHEMU
107 extern int sysctl_ieee_emulation_warnings;
108 #endif
109 extern int sysctl_userprocess_debug;
110 extern int spin_retry;
111 #endif
112
113 extern int sysctl_hz_timer;
114
115 #ifdef CONFIG_BSD_PROCESS_ACCT
116 extern int acct_parm[];
117 #endif
118
119 #ifdef CONFIG_IA64
120 extern int no_unaligned_warning;
121 #endif
122
123 #ifdef CONFIG_RT_MUTEXES
124 extern int max_lock_depth;
125 #endif
126
127 #ifdef CONFIG_SYSCTL_SYSCALL
128 static int parse_table(int __user *, int, void __user *, size_t __user *,
129                 void __user *, size_t, ctl_table *);
130 #endif
131
132
133 #ifdef CONFIG_PROC_SYSCTL
134 static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
135                   void __user *buffer, size_t *lenp, loff_t *ppos);
136 static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
137                                void __user *buffer, size_t *lenp, loff_t *ppos);
138 #endif
139
140 static ctl_table root_table[];
141 static struct ctl_table_header root_table_header =
142         { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
143
144 static ctl_table kern_table[];
145 static ctl_table vm_table[];
146 static ctl_table fs_table[];
147 static ctl_table debug_table[];
148 static ctl_table dev_table[];
149 extern ctl_table random_table[];
150 #ifdef CONFIG_UNIX98_PTYS
151 extern ctl_table pty_table[];
152 #endif
153 #ifdef CONFIG_INOTIFY_USER
154 extern ctl_table inotify_table[];
155 #endif
156
157 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
158 int sysctl_legacy_va_layout;
159 #endif
160
161
162 /* /proc declarations: */
163
164 #ifdef CONFIG_PROC_SYSCTL
165
166 static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
167 static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
168 static int proc_opensys(struct inode *, struct file *);
169
170 const struct file_operations proc_sys_file_operations = {
171         .open           = proc_opensys,
172         .read           = proc_readsys,
173         .write          = proc_writesys,
174 };
175
176 extern struct proc_dir_entry *proc_sys_root;
177
178 static void register_proc_table(ctl_table *, struct proc_dir_entry *, void *);
179 static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
180 #endif
181
182 /* The default sysctl tables: */
183
184 static ctl_table root_table[] = {
185         {
186                 .ctl_name       = CTL_KERN,
187                 .procname       = "kernel",
188                 .mode           = 0555,
189                 .child          = kern_table,
190         },
191         {
192                 .ctl_name       = CTL_VM,
193                 .procname       = "vm",
194                 .mode           = 0555,
195                 .child          = vm_table,
196         },
197 #ifdef CONFIG_NET
198         {
199                 .ctl_name       = CTL_NET,
200                 .procname       = "net",
201                 .mode           = 0555,
202                 .child          = net_table,
203         },
204 #endif
205         {
206                 .ctl_name       = CTL_FS,
207                 .procname       = "fs",
208                 .mode           = 0555,
209                 .child          = fs_table,
210         },
211         {
212                 .ctl_name       = CTL_DEBUG,
213                 .procname       = "debug",
214                 .mode           = 0555,
215                 .child          = debug_table,
216         },
217         {
218                 .ctl_name       = CTL_DEV,
219                 .procname       = "dev",
220                 .mode           = 0555,
221                 .child          = dev_table,
222         },
223
224         { .ctl_name = 0 }
225 };
226
227 static ctl_table kern_table[] = {
228         {
229                 .ctl_name       = KERN_PANIC,
230                 .procname       = "panic",
231                 .data           = &panic_timeout,
232                 .maxlen         = sizeof(int),
233                 .mode           = 0644,
234                 .proc_handler   = &proc_dointvec,
235         },
236         {
237                 .ctl_name       = KERN_CORE_USES_PID,
238                 .procname       = "core_uses_pid",
239                 .data           = &core_uses_pid,
240                 .maxlen         = sizeof(int),
241                 .mode           = 0644,
242                 .proc_handler   = &proc_dointvec,
243         },
244         {
245                 .ctl_name       = KERN_CORE_PATTERN,
246                 .procname       = "core_pattern",
247                 .data           = core_pattern,
248                 .maxlen         = 128,
249                 .mode           = 0644,
250                 .proc_handler   = &proc_dostring,
251                 .strategy       = &sysctl_string,
252         },
253 #ifdef CONFIG_PROC_SYSCTL
254         {
255                 .ctl_name       = KERN_TAINTED,
256                 .procname       = "tainted",
257                 .data           = &tainted,
258                 .maxlen         = sizeof(int),
259                 .mode           = 0644,
260                 .proc_handler   = &proc_dointvec_taint,
261         },
262 #endif
263         {
264                 .ctl_name       = KERN_CAP_BSET,
265                 .procname       = "cap-bound",
266                 .data           = &cap_bset,
267                 .maxlen         = sizeof(kernel_cap_t),
268                 .mode           = 0600,
269                 .proc_handler   = &proc_dointvec_bset,
270         },
271 #ifdef CONFIG_BLK_DEV_INITRD
272         {
273                 .ctl_name       = KERN_REALROOTDEV,
274                 .procname       = "real-root-dev",
275                 .data           = &real_root_dev,
276                 .maxlen         = sizeof(int),
277                 .mode           = 0644,
278                 .proc_handler   = &proc_dointvec,
279         },
280 #endif
281 #ifdef __sparc__
282         {
283                 .ctl_name       = KERN_SPARC_REBOOT,
284                 .procname       = "reboot-cmd",
285                 .data           = reboot_command,
286                 .maxlen         = 256,
287                 .mode           = 0644,
288                 .proc_handler   = &proc_dostring,
289                 .strategy       = &sysctl_string,
290         },
291         {
292                 .ctl_name       = KERN_SPARC_STOP_A,
293                 .procname       = "stop-a",
294                 .data           = &stop_a_enabled,
295                 .maxlen         = sizeof (int),
296                 .mode           = 0644,
297                 .proc_handler   = &proc_dointvec,
298         },
299         {
300                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
301                 .procname       = "scons-poweroff",
302                 .data           = &scons_pwroff,
303                 .maxlen         = sizeof (int),
304                 .mode           = 0644,
305                 .proc_handler   = &proc_dointvec,
306         },
307 #endif
308 #ifdef __hppa__
309         {
310                 .ctl_name       = KERN_HPPA_PWRSW,
311                 .procname       = "soft-power",
312                 .data           = &pwrsw_enabled,
313                 .maxlen         = sizeof (int),
314                 .mode           = 0644,
315                 .proc_handler   = &proc_dointvec,
316         },
317         {
318                 .ctl_name       = KERN_HPPA_UNALIGNED,
319                 .procname       = "unaligned-trap",
320                 .data           = &unaligned_enabled,
321                 .maxlen         = sizeof (int),
322                 .mode           = 0644,
323                 .proc_handler   = &proc_dointvec,
324         },
325 #endif
326         {
327                 .ctl_name       = KERN_CTLALTDEL,
328                 .procname       = "ctrl-alt-del",
329                 .data           = &C_A_D,
330                 .maxlen         = sizeof(int),
331                 .mode           = 0644,
332                 .proc_handler   = &proc_dointvec,
333         },
334         {
335                 .ctl_name       = KERN_PRINTK,
336                 .procname       = "printk",
337                 .data           = &console_loglevel,
338                 .maxlen         = 4*sizeof(int),
339                 .mode           = 0644,
340                 .proc_handler   = &proc_dointvec,
341         },
342 #ifdef CONFIG_KMOD
343         {
344                 .ctl_name       = KERN_MODPROBE,
345                 .procname       = "modprobe",
346                 .data           = &modprobe_path,
347                 .maxlen         = KMOD_PATH_LEN,
348                 .mode           = 0644,
349                 .proc_handler   = &proc_dostring,
350                 .strategy       = &sysctl_string,
351         },
352 #endif
353 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
354         {
355                 .ctl_name       = KERN_HOTPLUG,
356                 .procname       = "hotplug",
357                 .data           = &uevent_helper,
358                 .maxlen         = UEVENT_HELPER_PATH_LEN,
359                 .mode           = 0644,
360                 .proc_handler   = &proc_dostring,
361                 .strategy       = &sysctl_string,
362         },
363 #endif
364 #ifdef CONFIG_CHR_DEV_SG
365         {
366                 .ctl_name       = KERN_SG_BIG_BUFF,
367                 .procname       = "sg-big-buff",
368                 .data           = &sg_big_buff,
369                 .maxlen         = sizeof (int),
370                 .mode           = 0444,
371                 .proc_handler   = &proc_dointvec,
372         },
373 #endif
374 #ifdef CONFIG_BSD_PROCESS_ACCT
375         {
376                 .ctl_name       = KERN_ACCT,
377                 .procname       = "acct",
378                 .data           = &acct_parm,
379                 .maxlen         = 3*sizeof(int),
380                 .mode           = 0644,
381                 .proc_handler   = &proc_dointvec,
382         },
383 #endif
384 #ifdef CONFIG_MAGIC_SYSRQ
385         {
386                 .ctl_name       = KERN_SYSRQ,
387                 .procname       = "sysrq",
388                 .data           = &__sysrq_enabled,
389                 .maxlen         = sizeof (int),
390                 .mode           = 0644,
391                 .proc_handler   = &proc_dointvec,
392         },
393 #endif
394 #ifdef CONFIG_PROC_SYSCTL
395         {
396                 .ctl_name       = KERN_CADPID,
397                 .procname       = "cad_pid",
398                 .data           = NULL,
399                 .maxlen         = sizeof (int),
400                 .mode           = 0600,
401                 .proc_handler   = &proc_do_cad_pid,
402         },
403 #endif
404         {
405                 .ctl_name       = KERN_MAX_THREADS,
406                 .procname       = "threads-max",
407                 .data           = &max_threads,
408                 .maxlen         = sizeof(int),
409                 .mode           = 0644,
410                 .proc_handler   = &proc_dointvec,
411         },
412         {
413                 .ctl_name       = KERN_RANDOM,
414                 .procname       = "random",
415                 .mode           = 0555,
416                 .child          = random_table,
417         },
418 #ifdef CONFIG_UNIX98_PTYS
419         {
420                 .ctl_name       = KERN_PTY,
421                 .procname       = "pty",
422                 .mode           = 0555,
423                 .child          = pty_table,
424         },
425 #endif
426         {
427                 .ctl_name       = KERN_OVERFLOWUID,
428                 .procname       = "overflowuid",
429                 .data           = &overflowuid,
430                 .maxlen         = sizeof(int),
431                 .mode           = 0644,
432                 .proc_handler   = &proc_dointvec_minmax,
433                 .strategy       = &sysctl_intvec,
434                 .extra1         = &minolduid,
435                 .extra2         = &maxolduid,
436         },
437         {
438                 .ctl_name       = KERN_OVERFLOWGID,
439                 .procname       = "overflowgid",
440                 .data           = &overflowgid,
441                 .maxlen         = sizeof(int),
442                 .mode           = 0644,
443                 .proc_handler   = &proc_dointvec_minmax,
444                 .strategy       = &sysctl_intvec,
445                 .extra1         = &minolduid,
446                 .extra2         = &maxolduid,
447         },
448 #ifdef CONFIG_S390
449 #ifdef CONFIG_MATHEMU
450         {
451                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
452                 .procname       = "ieee_emulation_warnings",
453                 .data           = &sysctl_ieee_emulation_warnings,
454                 .maxlen         = sizeof(int),
455                 .mode           = 0644,
456                 .proc_handler   = &proc_dointvec,
457         },
458 #endif
459 #ifdef CONFIG_NO_IDLE_HZ
460         {
461                 .ctl_name       = KERN_HZ_TIMER,
462                 .procname       = "hz_timer",
463                 .data           = &sysctl_hz_timer,
464                 .maxlen         = sizeof(int),
465                 .mode           = 0644,
466                 .proc_handler   = &proc_dointvec,
467         },
468 #endif
469         {
470                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
471                 .procname       = "userprocess_debug",
472                 .data           = &sysctl_userprocess_debug,
473                 .maxlen         = sizeof(int),
474                 .mode           = 0644,
475                 .proc_handler   = &proc_dointvec,
476         },
477 #endif
478         {
479                 .ctl_name       = KERN_PIDMAX,
480                 .procname       = "pid_max",
481                 .data           = &pid_max,
482                 .maxlen         = sizeof (int),
483                 .mode           = 0644,
484                 .proc_handler   = &proc_dointvec_minmax,
485                 .strategy       = sysctl_intvec,
486                 .extra1         = &pid_max_min,
487                 .extra2         = &pid_max_max,
488         },
489         {
490                 .ctl_name       = KERN_PANIC_ON_OOPS,
491                 .procname       = "panic_on_oops",
492                 .data           = &panic_on_oops,
493                 .maxlen         = sizeof(int),
494                 .mode           = 0644,
495                 .proc_handler   = &proc_dointvec,
496         },
497         {
498                 .ctl_name       = KERN_PRINTK_RATELIMIT,
499                 .procname       = "printk_ratelimit",
500                 .data           = &printk_ratelimit_jiffies,
501                 .maxlen         = sizeof(int),
502                 .mode           = 0644,
503                 .proc_handler   = &proc_dointvec_jiffies,
504                 .strategy       = &sysctl_jiffies,
505         },
506         {
507                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
508                 .procname       = "printk_ratelimit_burst",
509                 .data           = &printk_ratelimit_burst,
510                 .maxlen         = sizeof(int),
511                 .mode           = 0644,
512                 .proc_handler   = &proc_dointvec,
513         },
514         {
515                 .ctl_name       = KERN_NGROUPS_MAX,
516                 .procname       = "ngroups_max",
517                 .data           = &ngroups_max,
518                 .maxlen         = sizeof (int),
519                 .mode           = 0444,
520                 .proc_handler   = &proc_dointvec,
521         },
522 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
523         {
524                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
525                 .procname       = "unknown_nmi_panic",
526                 .data           = &unknown_nmi_panic,
527                 .maxlen         = sizeof (int),
528                 .mode           = 0644,
529                 .proc_handler   = &proc_dointvec,
530         },
531         {
532                 .ctl_name       = KERN_NMI_WATCHDOG,
533                 .procname       = "nmi_watchdog",
534                 .data           = &nmi_watchdog_enabled,
535                 .maxlen         = sizeof (int),
536                 .mode           = 0644,
537                 .proc_handler   = &proc_nmi_enabled,
538         },
539 #endif
540 #if defined(CONFIG_X86)
541         {
542                 .ctl_name       = KERN_PANIC_ON_NMI,
543                 .procname       = "panic_on_unrecovered_nmi",
544                 .data           = &panic_on_unrecovered_nmi,
545                 .maxlen         = sizeof(int),
546                 .mode           = 0644,
547                 .proc_handler   = &proc_dointvec,
548         },
549         {
550                 .ctl_name       = KERN_BOOTLOADER_TYPE,
551                 .procname       = "bootloader_type",
552                 .data           = &bootloader_type,
553                 .maxlen         = sizeof (int),
554                 .mode           = 0444,
555                 .proc_handler   = &proc_dointvec,
556         },
557         {
558                 .ctl_name       = CTL_UNNUMBERED,
559                 .procname       = "kstack_depth_to_print",
560                 .data           = &kstack_depth_to_print,
561                 .maxlen         = sizeof(int),
562                 .mode           = 0644,
563                 .proc_handler   = &proc_dointvec,
564         },
565 #endif
566 #if defined(CONFIG_MMU)
567         {
568                 .ctl_name       = KERN_RANDOMIZE,
569                 .procname       = "randomize_va_space",
570                 .data           = &randomize_va_space,
571                 .maxlen         = sizeof(int),
572                 .mode           = 0644,
573                 .proc_handler   = &proc_dointvec,
574         },
575 #endif
576 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
577         {
578                 .ctl_name       = KERN_SPIN_RETRY,
579                 .procname       = "spin_retry",
580                 .data           = &spin_retry,
581                 .maxlen         = sizeof (int),
582                 .mode           = 0644,
583                 .proc_handler   = &proc_dointvec,
584         },
585 #endif
586 #ifdef CONFIG_ACPI_SLEEP
587         {
588                 .ctl_name       = KERN_ACPI_VIDEO_FLAGS,
589                 .procname       = "acpi_video_flags",
590                 .data           = &acpi_video_flags,
591                 .maxlen         = sizeof (unsigned long),
592                 .mode           = 0644,
593                 .proc_handler   = &proc_doulongvec_minmax,
594         },
595 #endif
596 #ifdef CONFIG_IA64
597         {
598                 .ctl_name       = KERN_IA64_UNALIGNED,
599                 .procname       = "ignore-unaligned-usertrap",
600                 .data           = &no_unaligned_warning,
601                 .maxlen         = sizeof (int),
602                 .mode           = 0644,
603                 .proc_handler   = &proc_dointvec,
604         },
605 #endif
606 #ifdef CONFIG_COMPAT
607         {
608                 .ctl_name       = KERN_COMPAT_LOG,
609                 .procname       = "compat-log",
610                 .data           = &compat_log,
611                 .maxlen         = sizeof (int),
612                 .mode           = 0644,
613                 .proc_handler   = &proc_dointvec,
614         },
615 #endif
616 #ifdef CONFIG_RT_MUTEXES
617         {
618                 .ctl_name       = KERN_MAX_LOCK_DEPTH,
619                 .procname       = "max_lock_depth",
620                 .data           = &max_lock_depth,
621                 .maxlen         = sizeof(int),
622                 .mode           = 0644,
623                 .proc_handler   = &proc_dointvec,
624         },
625 #endif
626
627         { .ctl_name = 0 }
628 };
629
630 /* Constants for minimum and maximum testing in vm_table.
631    We use these as one-element integer vectors. */
632 static int zero;
633 static int one_hundred = 100;
634
635
636 static ctl_table vm_table[] = {
637         {
638                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
639                 .procname       = "overcommit_memory",
640                 .data           = &sysctl_overcommit_memory,
641                 .maxlen         = sizeof(sysctl_overcommit_memory),
642                 .mode           = 0644,
643                 .proc_handler   = &proc_dointvec,
644         },
645         {
646                 .ctl_name       = VM_PANIC_ON_OOM,
647                 .procname       = "panic_on_oom",
648                 .data           = &sysctl_panic_on_oom,
649                 .maxlen         = sizeof(sysctl_panic_on_oom),
650                 .mode           = 0644,
651                 .proc_handler   = &proc_dointvec,
652         },
653         {
654                 .ctl_name       = VM_OVERCOMMIT_RATIO,
655                 .procname       = "overcommit_ratio",
656                 .data           = &sysctl_overcommit_ratio,
657                 .maxlen         = sizeof(sysctl_overcommit_ratio),
658                 .mode           = 0644,
659                 .proc_handler   = &proc_dointvec,
660         },
661         {
662                 .ctl_name       = VM_PAGE_CLUSTER,
663                 .procname       = "page-cluster", 
664                 .data           = &page_cluster,
665                 .maxlen         = sizeof(int),
666                 .mode           = 0644,
667                 .proc_handler   = &proc_dointvec,
668         },
669         {
670                 .ctl_name       = VM_DIRTY_BACKGROUND,
671                 .procname       = "dirty_background_ratio",
672                 .data           = &dirty_background_ratio,
673                 .maxlen         = sizeof(dirty_background_ratio),
674                 .mode           = 0644,
675                 .proc_handler   = &proc_dointvec_minmax,
676                 .strategy       = &sysctl_intvec,
677                 .extra1         = &zero,
678                 .extra2         = &one_hundred,
679         },
680         {
681                 .ctl_name       = VM_DIRTY_RATIO,
682                 .procname       = "dirty_ratio",
683                 .data           = &vm_dirty_ratio,
684                 .maxlen         = sizeof(vm_dirty_ratio),
685                 .mode           = 0644,
686                 .proc_handler   = &proc_dointvec_minmax,
687                 .strategy       = &sysctl_intvec,
688                 .extra1         = &zero,
689                 .extra2         = &one_hundred,
690         },
691         {
692                 .ctl_name       = VM_DIRTY_WB_CS,
693                 .procname       = "dirty_writeback_centisecs",
694                 .data           = &dirty_writeback_interval,
695                 .maxlen         = sizeof(dirty_writeback_interval),
696                 .mode           = 0644,
697                 .proc_handler   = &dirty_writeback_centisecs_handler,
698         },
699         {
700                 .ctl_name       = VM_DIRTY_EXPIRE_CS,
701                 .procname       = "dirty_expire_centisecs",
702                 .data           = &dirty_expire_interval,
703                 .maxlen         = sizeof(dirty_expire_interval),
704                 .mode           = 0644,
705                 .proc_handler   = &proc_dointvec_userhz_jiffies,
706         },
707         {
708                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
709                 .procname       = "nr_pdflush_threads",
710                 .data           = &nr_pdflush_threads,
711                 .maxlen         = sizeof nr_pdflush_threads,
712                 .mode           = 0444 /* read-only*/,
713                 .proc_handler   = &proc_dointvec,
714         },
715         {
716                 .ctl_name       = VM_SWAPPINESS,
717                 .procname       = "swappiness",
718                 .data           = &vm_swappiness,
719                 .maxlen         = sizeof(vm_swappiness),
720                 .mode           = 0644,
721                 .proc_handler   = &proc_dointvec_minmax,
722                 .strategy       = &sysctl_intvec,
723                 .extra1         = &zero,
724                 .extra2         = &one_hundred,
725         },
726 #ifdef CONFIG_HUGETLB_PAGE
727          {
728                 .ctl_name       = VM_HUGETLB_PAGES,
729                 .procname       = "nr_hugepages",
730                 .data           = &max_huge_pages,
731                 .maxlen         = sizeof(unsigned long),
732                 .mode           = 0644,
733                 .proc_handler   = &hugetlb_sysctl_handler,
734                 .extra1         = (void *)&hugetlb_zero,
735                 .extra2         = (void *)&hugetlb_infinity,
736          },
737          {
738                 .ctl_name       = VM_HUGETLB_GROUP,
739                 .procname       = "hugetlb_shm_group",
740                 .data           = &sysctl_hugetlb_shm_group,
741                 .maxlen         = sizeof(gid_t),
742                 .mode           = 0644,
743                 .proc_handler   = &proc_dointvec,
744          },
745 #endif
746         {
747                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
748                 .procname       = "lowmem_reserve_ratio",
749                 .data           = &sysctl_lowmem_reserve_ratio,
750                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
751                 .mode           = 0644,
752                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
753                 .strategy       = &sysctl_intvec,
754         },
755         {
756                 .ctl_name       = VM_DROP_PAGECACHE,
757                 .procname       = "drop_caches",
758                 .data           = &sysctl_drop_caches,
759                 .maxlen         = sizeof(int),
760                 .mode           = 0644,
761                 .proc_handler   = drop_caches_sysctl_handler,
762                 .strategy       = &sysctl_intvec,
763         },
764         {
765                 .ctl_name       = VM_MIN_FREE_KBYTES,
766                 .procname       = "min_free_kbytes",
767                 .data           = &min_free_kbytes,
768                 .maxlen         = sizeof(min_free_kbytes),
769                 .mode           = 0644,
770                 .proc_handler   = &min_free_kbytes_sysctl_handler,
771                 .strategy       = &sysctl_intvec,
772                 .extra1         = &zero,
773         },
774         {
775                 .ctl_name       = VM_PERCPU_PAGELIST_FRACTION,
776                 .procname       = "percpu_pagelist_fraction",
777                 .data           = &percpu_pagelist_fraction,
778                 .maxlen         = sizeof(percpu_pagelist_fraction),
779                 .mode           = 0644,
780                 .proc_handler   = &percpu_pagelist_fraction_sysctl_handler,
781                 .strategy       = &sysctl_intvec,
782                 .extra1         = &min_percpu_pagelist_fract,
783         },
784 #ifdef CONFIG_MMU
785         {
786                 .ctl_name       = VM_MAX_MAP_COUNT,
787                 .procname       = "max_map_count",
788                 .data           = &sysctl_max_map_count,
789                 .maxlen         = sizeof(sysctl_max_map_count),
790                 .mode           = 0644,
791                 .proc_handler   = &proc_dointvec
792         },
793 #endif
794         {
795                 .ctl_name       = VM_LAPTOP_MODE,
796                 .procname       = "laptop_mode",
797                 .data           = &laptop_mode,
798                 .maxlen         = sizeof(laptop_mode),
799                 .mode           = 0644,
800                 .proc_handler   = &proc_dointvec_jiffies,
801                 .strategy       = &sysctl_jiffies,
802         },
803         {
804                 .ctl_name       = VM_BLOCK_DUMP,
805                 .procname       = "block_dump",
806                 .data           = &block_dump,
807                 .maxlen         = sizeof(block_dump),
808                 .mode           = 0644,
809                 .proc_handler   = &proc_dointvec,
810                 .strategy       = &sysctl_intvec,
811                 .extra1         = &zero,
812         },
813         {
814                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
815                 .procname       = "vfs_cache_pressure",
816                 .data           = &sysctl_vfs_cache_pressure,
817                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
818                 .mode           = 0644,
819                 .proc_handler   = &proc_dointvec,
820                 .strategy       = &sysctl_intvec,
821                 .extra1         = &zero,
822         },
823 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
824         {
825                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
826                 .procname       = "legacy_va_layout",
827                 .data           = &sysctl_legacy_va_layout,
828                 .maxlen         = sizeof(sysctl_legacy_va_layout),
829                 .mode           = 0644,
830                 .proc_handler   = &proc_dointvec,
831                 .strategy       = &sysctl_intvec,
832                 .extra1         = &zero,
833         },
834 #endif
835 #ifdef CONFIG_NUMA
836         {
837                 .ctl_name       = VM_ZONE_RECLAIM_MODE,
838                 .procname       = "zone_reclaim_mode",
839                 .data           = &zone_reclaim_mode,
840                 .maxlen         = sizeof(zone_reclaim_mode),
841                 .mode           = 0644,
842                 .proc_handler   = &proc_dointvec,
843                 .strategy       = &sysctl_intvec,
844                 .extra1         = &zero,
845         },
846         {
847                 .ctl_name       = VM_MIN_UNMAPPED,
848                 .procname       = "min_unmapped_ratio",
849                 .data           = &sysctl_min_unmapped_ratio,
850                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
851                 .mode           = 0644,
852                 .proc_handler   = &sysctl_min_unmapped_ratio_sysctl_handler,
853                 .strategy       = &sysctl_intvec,
854                 .extra1         = &zero,
855                 .extra2         = &one_hundred,
856         },
857         {
858                 .ctl_name       = VM_MIN_SLAB,
859                 .procname       = "min_slab_ratio",
860                 .data           = &sysctl_min_slab_ratio,
861                 .maxlen         = sizeof(sysctl_min_slab_ratio),
862                 .mode           = 0644,
863                 .proc_handler   = &sysctl_min_slab_ratio_sysctl_handler,
864                 .strategy       = &sysctl_intvec,
865                 .extra1         = &zero,
866                 .extra2         = &one_hundred,
867         },
868 #endif
869 #ifdef CONFIG_X86_32
870         {
871                 .ctl_name       = VM_VDSO_ENABLED,
872                 .procname       = "vdso_enabled",
873                 .data           = &vdso_enabled,
874                 .maxlen         = sizeof(vdso_enabled),
875                 .mode           = 0644,
876                 .proc_handler   = &proc_dointvec,
877                 .strategy       = &sysctl_intvec,
878                 .extra1         = &zero,
879         },
880 #endif
881         { .ctl_name = 0 }
882 };
883
884 static ctl_table fs_table[] = {
885         {
886                 .ctl_name       = FS_NRINODE,
887                 .procname       = "inode-nr",
888                 .data           = &inodes_stat,
889                 .maxlen         = 2*sizeof(int),
890                 .mode           = 0444,
891                 .proc_handler   = &proc_dointvec,
892         },
893         {
894                 .ctl_name       = FS_STATINODE,
895                 .procname       = "inode-state",
896                 .data           = &inodes_stat,
897                 .maxlen         = 7*sizeof(int),
898                 .mode           = 0444,
899                 .proc_handler   = &proc_dointvec,
900         },
901         {
902                 .ctl_name       = FS_NRFILE,
903                 .procname       = "file-nr",
904                 .data           = &files_stat,
905                 .maxlen         = 3*sizeof(int),
906                 .mode           = 0444,
907                 .proc_handler   = &proc_nr_files,
908         },
909         {
910                 .ctl_name       = FS_MAXFILE,
911                 .procname       = "file-max",
912                 .data           = &files_stat.max_files,
913                 .maxlen         = sizeof(int),
914                 .mode           = 0644,
915                 .proc_handler   = &proc_dointvec,
916         },
917         {
918                 .ctl_name       = FS_DENTRY,
919                 .procname       = "dentry-state",
920                 .data           = &dentry_stat,
921                 .maxlen         = 6*sizeof(int),
922                 .mode           = 0444,
923                 .proc_handler   = &proc_dointvec,
924         },
925         {
926                 .ctl_name       = FS_OVERFLOWUID,
927                 .procname       = "overflowuid",
928                 .data           = &fs_overflowuid,
929                 .maxlen         = sizeof(int),
930                 .mode           = 0644,
931                 .proc_handler   = &proc_dointvec_minmax,
932                 .strategy       = &sysctl_intvec,
933                 .extra1         = &minolduid,
934                 .extra2         = &maxolduid,
935         },
936         {
937                 .ctl_name       = FS_OVERFLOWGID,
938                 .procname       = "overflowgid",
939                 .data           = &fs_overflowgid,
940                 .maxlen         = sizeof(int),
941                 .mode           = 0644,
942                 .proc_handler   = &proc_dointvec_minmax,
943                 .strategy       = &sysctl_intvec,
944                 .extra1         = &minolduid,
945                 .extra2         = &maxolduid,
946         },
947         {
948                 .ctl_name       = FS_LEASES,
949                 .procname       = "leases-enable",
950                 .data           = &leases_enable,
951                 .maxlen         = sizeof(int),
952                 .mode           = 0644,
953                 .proc_handler   = &proc_dointvec,
954         },
955 #ifdef CONFIG_DNOTIFY
956         {
957                 .ctl_name       = FS_DIR_NOTIFY,
958                 .procname       = "dir-notify-enable",
959                 .data           = &dir_notify_enable,
960                 .maxlen         = sizeof(int),
961                 .mode           = 0644,
962                 .proc_handler   = &proc_dointvec,
963         },
964 #endif
965 #ifdef CONFIG_MMU
966         {
967                 .ctl_name       = FS_LEASE_TIME,
968                 .procname       = "lease-break-time",
969                 .data           = &lease_break_time,
970                 .maxlen         = sizeof(int),
971                 .mode           = 0644,
972                 .proc_handler   = &proc_dointvec,
973         },
974         {
975                 .ctl_name       = FS_AIO_NR,
976                 .procname       = "aio-nr",
977                 .data           = &aio_nr,
978                 .maxlen         = sizeof(aio_nr),
979                 .mode           = 0444,
980                 .proc_handler   = &proc_doulongvec_minmax,
981         },
982         {
983                 .ctl_name       = FS_AIO_MAX_NR,
984                 .procname       = "aio-max-nr",
985                 .data           = &aio_max_nr,
986                 .maxlen         = sizeof(aio_max_nr),
987                 .mode           = 0644,
988                 .proc_handler   = &proc_doulongvec_minmax,
989         },
990 #ifdef CONFIG_INOTIFY_USER
991         {
992                 .ctl_name       = FS_INOTIFY,
993                 .procname       = "inotify",
994                 .mode           = 0555,
995                 .child          = inotify_table,
996         },
997 #endif  
998 #endif
999         {
1000                 .ctl_name       = KERN_SETUID_DUMPABLE,
1001                 .procname       = "suid_dumpable",
1002                 .data           = &suid_dumpable,
1003                 .maxlen         = sizeof(int),
1004                 .mode           = 0644,
1005                 .proc_handler   = &proc_dointvec,
1006         },
1007         { .ctl_name = 0 }
1008 };
1009
1010 static ctl_table debug_table[] = {
1011         { .ctl_name = 0 }
1012 };
1013
1014 static ctl_table dev_table[] = {
1015         { .ctl_name = 0 }
1016 };
1017
1018 static DEFINE_SPINLOCK(sysctl_lock);
1019
1020 /* called under sysctl_lock */
1021 static int use_table(struct ctl_table_header *p)
1022 {
1023         if (unlikely(p->unregistering))
1024                 return 0;
1025         p->used++;
1026         return 1;
1027 }
1028
1029 /* called under sysctl_lock */
1030 static void unuse_table(struct ctl_table_header *p)
1031 {
1032         if (!--p->used)
1033                 if (unlikely(p->unregistering))
1034                         complete(p->unregistering);
1035 }
1036
1037 /* called under sysctl_lock, will reacquire if has to wait */
1038 static void start_unregistering(struct ctl_table_header *p)
1039 {
1040         /*
1041          * if p->used is 0, nobody will ever touch that entry again;
1042          * we'll eliminate all paths to it before dropping sysctl_lock
1043          */
1044         if (unlikely(p->used)) {
1045                 struct completion wait;
1046                 init_completion(&wait);
1047                 p->unregistering = &wait;
1048                 spin_unlock(&sysctl_lock);
1049                 wait_for_completion(&wait);
1050                 spin_lock(&sysctl_lock);
1051         }
1052         /*
1053          * do not remove from the list until nobody holds it; walking the
1054          * list in do_sysctl() relies on that.
1055          */
1056         list_del_init(&p->ctl_entry);
1057 }
1058
1059 void __init sysctl_init(void)
1060 {
1061 #ifdef CONFIG_PROC_SYSCTL
1062         register_proc_table(root_table, proc_sys_root, &root_table_header);
1063 #endif
1064 }
1065
1066 #ifdef CONFIG_SYSCTL_SYSCALL
1067 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1068                void __user *newval, size_t newlen)
1069 {
1070         struct list_head *tmp;
1071         int error = -ENOTDIR;
1072
1073         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1074                 return -ENOTDIR;
1075         if (oldval) {
1076                 int old_len;
1077                 if (!oldlenp || get_user(old_len, oldlenp))
1078                         return -EFAULT;
1079         }
1080         spin_lock(&sysctl_lock);
1081         tmp = &root_table_header.ctl_entry;
1082         do {
1083                 struct ctl_table_header *head =
1084                         list_entry(tmp, struct ctl_table_header, ctl_entry);
1085
1086                 if (!use_table(head))
1087                         continue;
1088
1089                 spin_unlock(&sysctl_lock);
1090
1091                 error = parse_table(name, nlen, oldval, oldlenp, 
1092                                         newval, newlen, head->ctl_table);
1093
1094                 spin_lock(&sysctl_lock);
1095                 unuse_table(head);
1096                 if (error != -ENOTDIR)
1097                         break;
1098         } while ((tmp = tmp->next) != &root_table_header.ctl_entry);
1099         spin_unlock(&sysctl_lock);
1100         return error;
1101 }
1102
1103 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1104 {
1105         struct __sysctl_args tmp;
1106         int error;
1107
1108         if (copy_from_user(&tmp, args, sizeof(tmp)))
1109                 return -EFAULT;
1110
1111         lock_kernel();
1112         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1113                           tmp.newval, tmp.newlen);
1114         unlock_kernel();
1115         return error;
1116 }
1117 #endif /* CONFIG_SYSCTL_SYSCALL */
1118
1119 /*
1120  * ctl_perm does NOT grant the superuser all rights automatically, because
1121  * some sysctl variables are readonly even to root.
1122  */
1123
1124 static int test_perm(int mode, int op)
1125 {
1126         if (!current->euid)
1127                 mode >>= 6;
1128         else if (in_egroup_p(0))
1129                 mode >>= 3;
1130         if ((mode & op & 0007) == op)
1131                 return 0;
1132         return -EACCES;
1133 }
1134
1135 static inline int ctl_perm(ctl_table *table, int op)
1136 {
1137         int error;
1138         error = security_sysctl(table, op);
1139         if (error)
1140                 return error;
1141         return test_perm(table->mode, op);
1142 }
1143
1144 #ifdef CONFIG_SYSCTL_SYSCALL
1145 static int parse_table(int __user *name, int nlen,
1146                        void __user *oldval, size_t __user *oldlenp,
1147                        void __user *newval, size_t newlen,
1148                        ctl_table *table)
1149 {
1150         int n;
1151 repeat:
1152         if (!nlen)
1153                 return -ENOTDIR;
1154         if (get_user(n, name))
1155                 return -EFAULT;
1156         for ( ; table->ctl_name || table->procname; table++) {
1157                 if (!table->ctl_name)
1158                         continue;
1159                 if (n == table->ctl_name || table->ctl_name == CTL_ANY) {
1160                         int error;
1161                         if (table->child) {
1162                                 if (ctl_perm(table, 001))
1163                                         return -EPERM;
1164                                 if (table->strategy) {
1165                                         error = table->strategy(
1166                                                 table, name, nlen,
1167                                                 oldval, oldlenp,
1168                                                 newval, newlen);
1169                                         if (error)
1170                                                 return error;
1171                                 }
1172                                 name++;
1173                                 nlen--;
1174                                 table = table->child;
1175                                 goto repeat;
1176                         }
1177                         error = do_sysctl_strategy(table, name, nlen,
1178                                                    oldval, oldlenp,
1179                                                    newval, newlen);
1180                         return error;
1181                 }
1182         }
1183         return -ENOTDIR;
1184 }
1185
1186 /* Perform the actual read/write of a sysctl table entry. */
1187 int do_sysctl_strategy (ctl_table *table, 
1188                         int __user *name, int nlen,
1189                         void __user *oldval, size_t __user *oldlenp,
1190                         void __user *newval, size_t newlen)
1191 {
1192         int op = 0, rc;
1193         size_t len;
1194
1195         if (oldval)
1196                 op |= 004;
1197         if (newval) 
1198                 op |= 002;
1199         if (ctl_perm(table, op))
1200                 return -EPERM;
1201
1202         if (table->strategy) {
1203                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1204                                      newval, newlen);
1205                 if (rc < 0)
1206                         return rc;
1207                 if (rc > 0)
1208                         return 0;
1209         }
1210
1211         /* If there is no strategy routine, or if the strategy returns
1212          * zero, proceed with automatic r/w */
1213         if (table->data && table->maxlen) {
1214                 if (oldval && oldlenp) {
1215                         if (get_user(len, oldlenp))
1216                                 return -EFAULT;
1217                         if (len) {
1218                                 if (len > table->maxlen)
1219                                         len = table->maxlen;
1220                                 if(copy_to_user(oldval, table->data, len))
1221                                         return -EFAULT;
1222                                 if(put_user(len, oldlenp))
1223                                         return -EFAULT;
1224                         }
1225                 }
1226                 if (newval && newlen) {
1227                         len = newlen;
1228                         if (len > table->maxlen)
1229                                 len = table->maxlen;
1230                         if(copy_from_user(table->data, newval, len))
1231                                 return -EFAULT;
1232                 }
1233         }
1234         return 0;
1235 }
1236 #endif /* CONFIG_SYSCTL_SYSCALL */
1237
1238 /**
1239  * register_sysctl_table - register a sysctl hierarchy
1240  * @table: the top-level table structure
1241  * @insert_at_head: whether the entry should be inserted in front or at the end
1242  *
1243  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1244  * array. An entry with a ctl_name of 0 terminates the table. 
1245  *
1246  * The members of the &ctl_table structure are used as follows:
1247  *
1248  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1249  *            must be unique within that level of sysctl
1250  *
1251  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1252  *            enter a sysctl file
1253  *
1254  * data - a pointer to data for use by proc_handler
1255  *
1256  * maxlen - the maximum size in bytes of the data
1257  *
1258  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1259  *
1260  * child - a pointer to the child sysctl table if this entry is a directory, or
1261  *         %NULL.
1262  *
1263  * proc_handler - the text handler routine (described below)
1264  *
1265  * strategy - the strategy routine (described below)
1266  *
1267  * de - for internal use by the sysctl routines
1268  *
1269  * extra1, extra2 - extra pointers usable by the proc handler routines
1270  *
1271  * Leaf nodes in the sysctl tree will be represented by a single file
1272  * under /proc; non-leaf nodes will be represented by directories.
1273  *
1274  * sysctl(2) can automatically manage read and write requests through
1275  * the sysctl table.  The data and maxlen fields of the ctl_table
1276  * struct enable minimal validation of the values being written to be
1277  * performed, and the mode field allows minimal authentication.
1278  *
1279  * More sophisticated management can be enabled by the provision of a
1280  * strategy routine with the table entry.  This will be called before
1281  * any automatic read or write of the data is performed.
1282  *
1283  * The strategy routine may return
1284  *
1285  * < 0 - Error occurred (error is passed to user process)
1286  *
1287  * 0   - OK - proceed with automatic read or write.
1288  *
1289  * > 0 - OK - read or write has been done by the strategy routine, so
1290  *       return immediately.
1291  *
1292  * There must be a proc_handler routine for any terminal nodes
1293  * mirrored under /proc/sys (non-terminals are handled by a built-in
1294  * directory handler).  Several default handlers are available to
1295  * cover common cases -
1296  *
1297  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1298  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(), 
1299  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1300  *
1301  * It is the handler's job to read the input buffer from user memory
1302  * and process it. The handler should return 0 on success.
1303  *
1304  * This routine returns %NULL on a failure to register, and a pointer
1305  * to the table header on success.
1306  */
1307 struct ctl_table_header *register_sysctl_table(ctl_table * table, 
1308                                                int insert_at_head)
1309 {
1310         struct ctl_table_header *tmp;
1311         tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1312         if (!tmp)
1313                 return NULL;
1314         tmp->ctl_table = table;
1315         INIT_LIST_HEAD(&tmp->ctl_entry);
1316         tmp->used = 0;
1317         tmp->unregistering = NULL;
1318         spin_lock(&sysctl_lock);
1319         if (insert_at_head)
1320                 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
1321         else
1322                 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1323         spin_unlock(&sysctl_lock);
1324 #ifdef CONFIG_PROC_SYSCTL
1325         register_proc_table(table, proc_sys_root, tmp);
1326 #endif
1327         return tmp;
1328 }
1329
1330 /**
1331  * unregister_sysctl_table - unregister a sysctl table hierarchy
1332  * @header: the header returned from register_sysctl_table
1333  *
1334  * Unregisters the sysctl table and all children. proc entries may not
1335  * actually be removed until they are no longer used by anyone.
1336  */
1337 void unregister_sysctl_table(struct ctl_table_header * header)
1338 {
1339         might_sleep();
1340         spin_lock(&sysctl_lock);
1341         start_unregistering(header);
1342 #ifdef CONFIG_PROC_SYSCTL
1343         unregister_proc_table(header->ctl_table, proc_sys_root);
1344 #endif
1345         spin_unlock(&sysctl_lock);
1346         kfree(header);
1347 }
1348
1349 #else /* !CONFIG_SYSCTL */
1350 struct ctl_table_header * register_sysctl_table(ctl_table * table,
1351                                                 int insert_at_head)
1352 {
1353         return NULL;
1354 }
1355
1356 void unregister_sysctl_table(struct ctl_table_header * table)
1357 {
1358 }
1359
1360 #endif /* CONFIG_SYSCTL */
1361
1362 /*
1363  * /proc/sys support
1364  */
1365
1366 #ifdef CONFIG_PROC_SYSCTL
1367
1368 /* Scan the sysctl entries in table and add them all into /proc */
1369 static void register_proc_table(ctl_table * table, struct proc_dir_entry *root, void *set)
1370 {
1371         struct proc_dir_entry *de;
1372         int len;
1373         mode_t mode;
1374         
1375         for (; table->ctl_name || table->procname; table++) {
1376                 /* Can't do anything without a proc name. */
1377                 if (!table->procname)
1378                         continue;
1379                 /* Maybe we can't do anything with it... */
1380                 if (!table->proc_handler && !table->child) {
1381                         printk(KERN_WARNING "SYSCTL: Can't register %s\n",
1382                                 table->procname);
1383                         continue;
1384                 }
1385
1386                 len = strlen(table->procname);
1387                 mode = table->mode;
1388
1389                 de = NULL;
1390                 if (table->proc_handler)
1391                         mode |= S_IFREG;
1392                 else {
1393                         mode |= S_IFDIR;
1394                         for (de = root->subdir; de; de = de->next) {
1395                                 if (proc_match(len, table->procname, de))
1396                                         break;
1397                         }
1398                         /* If the subdir exists already, de is non-NULL */
1399                 }
1400
1401                 if (!de) {
1402                         de = create_proc_entry(table->procname, mode, root);
1403                         if (!de)
1404                                 continue;
1405                         de->set = set;
1406                         de->data = (void *) table;
1407                         if (table->proc_handler)
1408                                 de->proc_fops = &proc_sys_file_operations;
1409                 }
1410                 table->de = de;
1411                 if (de->mode & S_IFDIR)
1412                         register_proc_table(table->child, de, set);
1413         }
1414 }
1415
1416 /*
1417  * Unregister a /proc sysctl table and any subdirectories.
1418  */
1419 static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
1420 {
1421         struct proc_dir_entry *de;
1422         for (; table->ctl_name || table->procname; table++) {
1423                 if (!(de = table->de))
1424                         continue;
1425                 if (de->mode & S_IFDIR) {
1426                         if (!table->child) {
1427                                 printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
1428                                 continue;
1429                         }
1430                         unregister_proc_table(table->child, de);
1431
1432                         /* Don't unregister directories which still have entries.. */
1433                         if (de->subdir)
1434                                 continue;
1435                 }
1436
1437                 /*
1438                  * In any case, mark the entry as goner; we'll keep it
1439                  * around if it's busy, but we'll know to do nothing with
1440                  * its fields.  We are under sysctl_lock here.
1441                  */
1442                 de->data = NULL;
1443
1444                 /* Don't unregister proc entries that are still being used.. */
1445                 if (atomic_read(&de->count))
1446                         continue;
1447
1448                 table->de = NULL;
1449                 remove_proc_entry(table->procname, root);
1450         }
1451 }
1452
1453 static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
1454                           size_t count, loff_t *ppos)
1455 {
1456         int op;
1457         struct proc_dir_entry *de = PDE(file->f_path.dentry->d_inode);
1458         struct ctl_table *table;
1459         size_t res;
1460         ssize_t error = -ENOTDIR;
1461         
1462         spin_lock(&sysctl_lock);
1463         if (de && de->data && use_table(de->set)) {
1464                 /*
1465                  * at that point we know that sysctl was not unregistered
1466                  * and won't be until we finish
1467                  */
1468                 spin_unlock(&sysctl_lock);
1469                 table = (struct ctl_table *) de->data;
1470                 if (!table || !table->proc_handler)
1471                         goto out;
1472                 error = -EPERM;
1473                 op = (write ? 002 : 004);
1474                 if (ctl_perm(table, op))
1475                         goto out;
1476                 
1477                 /* careful: calling conventions are nasty here */
1478                 res = count;
1479                 error = (*table->proc_handler)(table, write, file,
1480                                                 buf, &res, ppos);
1481                 if (!error)
1482                         error = res;
1483         out:
1484                 spin_lock(&sysctl_lock);
1485                 unuse_table(de->set);
1486         }
1487         spin_unlock(&sysctl_lock);
1488         return error;
1489 }
1490
1491 static int proc_opensys(struct inode *inode, struct file *file)
1492 {
1493         if (file->f_mode & FMODE_WRITE) {
1494                 /*
1495                  * sysctl entries that are not writable,
1496                  * are _NOT_ writable, capabilities or not.
1497                  */
1498                 if (!(inode->i_mode & S_IWUSR))
1499                         return -EPERM;
1500         }
1501
1502         return 0;
1503 }
1504
1505 static ssize_t proc_readsys(struct file * file, char __user * buf,
1506                             size_t count, loff_t *ppos)
1507 {
1508         return do_rw_proc(0, file, buf, count, ppos);
1509 }
1510
1511 static ssize_t proc_writesys(struct file * file, const char __user * buf,
1512                              size_t count, loff_t *ppos)
1513 {
1514         return do_rw_proc(1, file, (char __user *) buf, count, ppos);
1515 }
1516
1517 static int _proc_do_string(void* data, int maxlen, int write,
1518                            struct file *filp, void __user *buffer,
1519                            size_t *lenp, loff_t *ppos)
1520 {
1521         size_t len;
1522         char __user *p;
1523         char c;
1524
1525         if (!data || !maxlen || !*lenp) {
1526                 *lenp = 0;
1527                 return 0;
1528         }
1529
1530         if (write) {
1531                 len = 0;
1532                 p = buffer;
1533                 while (len < *lenp) {
1534                         if (get_user(c, p++))
1535                                 return -EFAULT;
1536                         if (c == 0 || c == '\n')
1537                                 break;
1538                         len++;
1539                 }
1540                 if (len >= maxlen)
1541                         len = maxlen-1;
1542                 if(copy_from_user(data, buffer, len))
1543                         return -EFAULT;
1544                 ((char *) data)[len] = 0;
1545                 *ppos += *lenp;
1546         } else {
1547                 len = strlen(data);
1548                 if (len > maxlen)
1549                         len = maxlen;
1550
1551                 if (*ppos > len) {
1552                         *lenp = 0;
1553                         return 0;
1554                 }
1555
1556                 data += *ppos;
1557                 len  -= *ppos;
1558
1559                 if (len > *lenp)
1560                         len = *lenp;
1561                 if (len)
1562                         if(copy_to_user(buffer, data, len))
1563                                 return -EFAULT;
1564                 if (len < *lenp) {
1565                         if(put_user('\n', ((char __user *) buffer) + len))
1566                                 return -EFAULT;
1567                         len++;
1568                 }
1569                 *lenp = len;
1570                 *ppos += len;
1571         }
1572         return 0;
1573 }
1574
1575 /**
1576  * proc_dostring - read a string sysctl
1577  * @table: the sysctl table
1578  * @write: %TRUE if this is a write to the sysctl file
1579  * @filp: the file structure
1580  * @buffer: the user buffer
1581  * @lenp: the size of the user buffer
1582  * @ppos: file position
1583  *
1584  * Reads/writes a string from/to the user buffer. If the kernel
1585  * buffer provided is not large enough to hold the string, the
1586  * string is truncated. The copied string is %NULL-terminated.
1587  * If the string is being read by the user process, it is copied
1588  * and a newline '\n' is added. It is truncated if the buffer is
1589  * not large enough.
1590  *
1591  * Returns 0 on success.
1592  */
1593 int proc_dostring(ctl_table *table, int write, struct file *filp,
1594                   void __user *buffer, size_t *lenp, loff_t *ppos)
1595 {
1596         return _proc_do_string(table->data, table->maxlen, write, filp,
1597                                buffer, lenp, ppos);
1598 }
1599
1600
1601 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1602                                  int *valp,
1603                                  int write, void *data)
1604 {
1605         if (write) {
1606                 *valp = *negp ? -*lvalp : *lvalp;
1607         } else {
1608                 int val = *valp;
1609                 if (val < 0) {
1610                         *negp = -1;
1611                         *lvalp = (unsigned long)-val;
1612                 } else {
1613                         *negp = 0;
1614                         *lvalp = (unsigned long)val;
1615                 }
1616         }
1617         return 0;
1618 }
1619
1620 static int __do_proc_dointvec(void *tbl_data, ctl_table *table,
1621                   int write, struct file *filp, void __user *buffer,
1622                   size_t *lenp, loff_t *ppos,
1623                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1624                               int write, void *data),
1625                   void *data)
1626 {
1627 #define TMPBUFLEN 21
1628         int *i, vleft, first=1, neg, val;
1629         unsigned long lval;
1630         size_t left, len;
1631         
1632         char buf[TMPBUFLEN], *p;
1633         char __user *s = buffer;
1634         
1635         if (!tbl_data || !table->maxlen || !*lenp ||
1636             (*ppos && !write)) {
1637                 *lenp = 0;
1638                 return 0;
1639         }
1640         
1641         i = (int *) tbl_data;
1642         vleft = table->maxlen / sizeof(*i);
1643         left = *lenp;
1644
1645         if (!conv)
1646                 conv = do_proc_dointvec_conv;
1647
1648         for (; left && vleft--; i++, first=0) {
1649                 if (write) {
1650                         while (left) {
1651                                 char c;
1652                                 if (get_user(c, s))
1653                                         return -EFAULT;
1654                                 if (!isspace(c))
1655                                         break;
1656                                 left--;
1657                                 s++;
1658                         }
1659                         if (!left)
1660                                 break;
1661                         neg = 0;
1662                         len = left;
1663                         if (len > sizeof(buf) - 1)
1664                                 len = sizeof(buf) - 1;
1665                         if (copy_from_user(buf, s, len))
1666                                 return -EFAULT;
1667                         buf[len] = 0;
1668                         p = buf;
1669                         if (*p == '-' && left > 1) {
1670                                 neg = 1;
1671                                 p++;
1672                         }
1673                         if (*p < '0' || *p > '9')
1674                                 break;
1675
1676                         lval = simple_strtoul(p, &p, 0);
1677
1678                         len = p-buf;
1679                         if ((len < left) && *p && !isspace(*p))
1680                                 break;
1681                         if (neg)
1682                                 val = -val;
1683                         s += len;
1684                         left -= len;
1685
1686                         if (conv(&neg, &lval, i, 1, data))
1687                                 break;
1688                 } else {
1689                         p = buf;
1690                         if (!first)
1691                                 *p++ = '\t';
1692         
1693                         if (conv(&neg, &lval, i, 0, data))
1694                                 break;
1695
1696                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
1697                         len = strlen(buf);
1698                         if (len > left)
1699                                 len = left;
1700                         if(copy_to_user(s, buf, len))
1701                                 return -EFAULT;
1702                         left -= len;
1703                         s += len;
1704                 }
1705         }
1706
1707         if (!write && !first && left) {
1708                 if(put_user('\n', s))
1709                         return -EFAULT;
1710                 left--, s++;
1711         }
1712         if (write) {
1713                 while (left) {
1714                         char c;
1715                         if (get_user(c, s++))
1716                                 return -EFAULT;
1717                         if (!isspace(c))
1718                                 break;
1719                         left--;
1720                 }
1721         }
1722         if (write && first)
1723                 return -EINVAL;
1724         *lenp -= left;
1725         *ppos += *lenp;
1726         return 0;
1727 #undef TMPBUFLEN
1728 }
1729
1730 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1731                   void __user *buffer, size_t *lenp, loff_t *ppos,
1732                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1733                               int write, void *data),
1734                   void *data)
1735 {
1736         return __do_proc_dointvec(table->data, table, write, filp,
1737                         buffer, lenp, ppos, conv, data);
1738 }
1739
1740 /**
1741  * proc_dointvec - read a vector of integers
1742  * @table: the sysctl table
1743  * @write: %TRUE if this is a write to the sysctl file
1744  * @filp: the file structure
1745  * @buffer: the user buffer
1746  * @lenp: the size of the user buffer
1747  * @ppos: file position
1748  *
1749  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1750  * values from/to the user buffer, treated as an ASCII string. 
1751  *
1752  * Returns 0 on success.
1753  */
1754 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1755                      void __user *buffer, size_t *lenp, loff_t *ppos)
1756 {
1757     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1758                             NULL,NULL);
1759 }
1760
1761 #define OP_SET  0
1762 #define OP_AND  1
1763 #define OP_OR   2
1764
1765 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1766                                       int *valp,
1767                                       int write, void *data)
1768 {
1769         int op = *(int *)data;
1770         if (write) {
1771                 int val = *negp ? -*lvalp : *lvalp;
1772                 switch(op) {
1773                 case OP_SET:    *valp = val; break;
1774                 case OP_AND:    *valp &= val; break;
1775                 case OP_OR:     *valp |= val; break;
1776                 }
1777         } else {
1778                 int val = *valp;
1779                 if (val < 0) {
1780                         *negp = -1;
1781                         *lvalp = (unsigned long)-val;
1782                 } else {
1783                         *negp = 0;
1784                         *lvalp = (unsigned long)val;
1785                 }
1786         }
1787         return 0;
1788 }
1789
1790 /*
1791  *      init may raise the set.
1792  */
1793  
1794 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1795                         void __user *buffer, size_t *lenp, loff_t *ppos)
1796 {
1797         int op;
1798
1799         if (write && !capable(CAP_SYS_MODULE)) {
1800                 return -EPERM;
1801         }
1802
1803         op = is_init(current) ? OP_SET : OP_AND;
1804         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1805                                 do_proc_dointvec_bset_conv,&op);
1806 }
1807
1808 /*
1809  *      Taint values can only be increased
1810  */
1811 static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
1812                                void __user *buffer, size_t *lenp, loff_t *ppos)
1813 {
1814         int op;
1815
1816         if (!capable(CAP_SYS_ADMIN))
1817                 return -EPERM;
1818
1819         op = OP_OR;
1820         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1821                                 do_proc_dointvec_bset_conv,&op);
1822 }
1823
1824 struct do_proc_dointvec_minmax_conv_param {
1825         int *min;
1826         int *max;
1827 };
1828
1829 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp, 
1830                                         int *valp, 
1831                                         int write, void *data)
1832 {
1833         struct do_proc_dointvec_minmax_conv_param *param = data;
1834         if (write) {
1835                 int val = *negp ? -*lvalp : *lvalp;
1836                 if ((param->min && *param->min > val) ||
1837                     (param->max && *param->max < val))
1838                         return -EINVAL;
1839                 *valp = val;
1840         } else {
1841                 int val = *valp;
1842                 if (val < 0) {
1843                         *negp = -1;
1844                         *lvalp = (unsigned long)-val;
1845                 } else {
1846                         *negp = 0;
1847                         *lvalp = (unsigned long)val;
1848                 }
1849         }
1850         return 0;
1851 }
1852
1853 /**
1854  * proc_dointvec_minmax - read a vector of integers with min/max values
1855  * @table: the sysctl table
1856  * @write: %TRUE if this is a write to the sysctl file
1857  * @filp: the file structure
1858  * @buffer: the user buffer
1859  * @lenp: the size of the user buffer
1860  * @ppos: file position
1861  *
1862  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1863  * values from/to the user buffer, treated as an ASCII string.
1864  *
1865  * This routine will ensure the values are within the range specified by
1866  * table->extra1 (min) and table->extra2 (max).
1867  *
1868  * Returns 0 on success.
1869  */
1870 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1871                   void __user *buffer, size_t *lenp, loff_t *ppos)
1872 {
1873         struct do_proc_dointvec_minmax_conv_param param = {
1874                 .min = (int *) table->extra1,
1875                 .max = (int *) table->extra2,
1876         };
1877         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1878                                 do_proc_dointvec_minmax_conv, &param);
1879 }
1880
1881 static int __do_proc_doulongvec_minmax(void *data, ctl_table *table, int write,
1882                                      struct file *filp,
1883                                      void __user *buffer,
1884                                      size_t *lenp, loff_t *ppos,
1885                                      unsigned long convmul,
1886                                      unsigned long convdiv)
1887 {
1888 #define TMPBUFLEN 21
1889         unsigned long *i, *min, *max, val;
1890         int vleft, first=1, neg;
1891         size_t len, left;
1892         char buf[TMPBUFLEN], *p;
1893         char __user *s = buffer;
1894         
1895         if (!data || !table->maxlen || !*lenp ||
1896             (*ppos && !write)) {
1897                 *lenp = 0;
1898                 return 0;
1899         }
1900         
1901         i = (unsigned long *) data;
1902         min = (unsigned long *) table->extra1;
1903         max = (unsigned long *) table->extra2;
1904         vleft = table->maxlen / sizeof(unsigned long);
1905         left = *lenp;
1906         
1907         for (; left && vleft--; i++, min++, max++, first=0) {
1908                 if (write) {
1909                         while (left) {
1910                                 char c;
1911                                 if (get_user(c, s))
1912                                         return -EFAULT;
1913                                 if (!isspace(c))
1914                                         break;
1915                                 left--;
1916                                 s++;
1917                         }
1918                         if (!left)
1919                                 break;
1920                         neg = 0;
1921                         len = left;
1922                         if (len > TMPBUFLEN-1)
1923                                 len = TMPBUFLEN-1;
1924                         if (copy_from_user(buf, s, len))
1925                                 return -EFAULT;
1926                         buf[len] = 0;
1927                         p = buf;
1928                         if (*p == '-' && left > 1) {
1929                                 neg = 1;
1930                                 p++;
1931                         }
1932                         if (*p < '0' || *p > '9')
1933                                 break;
1934                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1935                         len = p-buf;
1936                         if ((len < left) && *p && !isspace(*p))
1937                                 break;
1938                         if (neg)
1939                                 val = -val;
1940                         s += len;
1941                         left -= len;
1942
1943                         if(neg)
1944                                 continue;
1945                         if ((min && val < *min) || (max && val > *max))
1946                                 continue;
1947                         *i = val;
1948                 } else {
1949                         p = buf;
1950                         if (!first)
1951                                 *p++ = '\t';
1952                         sprintf(p, "%lu", convdiv * (*i) / convmul);
1953                         len = strlen(buf);
1954                         if (len > left)
1955                                 len = left;
1956                         if(copy_to_user(s, buf, len))
1957                                 return -EFAULT;
1958                         left -= len;
1959                         s += len;
1960                 }
1961         }
1962
1963         if (!write && !first && left) {
1964                 if(put_user('\n', s))
1965                         return -EFAULT;
1966                 left--, s++;
1967         }
1968         if (write) {
1969                 while (left) {
1970                         char c;
1971                         if (get_user(c, s++))
1972                                 return -EFAULT;
1973                         if (!isspace(c))
1974                                 break;
1975                         left--;
1976                 }
1977         }
1978         if (write && first)
1979                 return -EINVAL;
1980         *lenp -= left;
1981         *ppos += *lenp;
1982         return 0;
1983 #undef TMPBUFLEN
1984 }
1985
1986 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1987                                      struct file *filp,
1988                                      void __user *buffer,
1989                                      size_t *lenp, loff_t *ppos,
1990                                      unsigned long convmul,
1991                                      unsigned long convdiv)
1992 {
1993         return __do_proc_doulongvec_minmax(table->data, table, write,
1994                         filp, buffer, lenp, ppos, convmul, convdiv);
1995 }
1996
1997 /**
1998  * proc_doulongvec_minmax - read a vector of long integers with min/max values
1999  * @table: the sysctl table
2000  * @write: %TRUE if this is a write to the sysctl file
2001  * @filp: the file structure
2002  * @buffer: the user buffer
2003  * @lenp: the size of the user buffer
2004  * @ppos: file position
2005  *
2006  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2007  * values from/to the user buffer, treated as an ASCII string.
2008  *
2009  * This routine will ensure the values are within the range specified by
2010  * table->extra1 (min) and table->extra2 (max).
2011  *
2012  * Returns 0 on success.
2013  */
2014 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2015                            void __user *buffer, size_t *lenp, loff_t *ppos)
2016 {
2017     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2018 }
2019
2020 /**
2021  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2022  * @table: the sysctl table
2023  * @write: %TRUE if this is a write to the sysctl file
2024  * @filp: the file structure
2025  * @buffer: the user buffer
2026  * @lenp: the size of the user buffer
2027  * @ppos: file position
2028  *
2029  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2030  * values from/to the user buffer, treated as an ASCII string. The values
2031  * are treated as milliseconds, and converted to jiffies when they are stored.
2032  *
2033  * This routine will ensure the values are within the range specified by
2034  * table->extra1 (min) and table->extra2 (max).
2035  *
2036  * Returns 0 on success.
2037  */
2038 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2039                                       struct file *filp,
2040                                       void __user *buffer,
2041                                       size_t *lenp, loff_t *ppos)
2042 {
2043     return do_proc_doulongvec_minmax(table, write, filp, buffer,
2044                                      lenp, ppos, HZ, 1000l);
2045 }
2046
2047
2048 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2049                                          int *valp,
2050                                          int write, void *data)
2051 {
2052         if (write) {
2053                 if (*lvalp > LONG_MAX / HZ)
2054                         return 1;
2055                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2056         } else {
2057                 int val = *valp;
2058                 unsigned long lval;
2059                 if (val < 0) {
2060                         *negp = -1;
2061                         lval = (unsigned long)-val;
2062                 } else {
2063                         *negp = 0;
2064                         lval = (unsigned long)val;
2065                 }
2066                 *lvalp = lval / HZ;
2067         }
2068         return 0;
2069 }
2070
2071 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2072                                                 int *valp,
2073                                                 int write, void *data)
2074 {
2075         if (write) {
2076                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2077                         return 1;
2078                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2079         } else {
2080                 int val = *valp;
2081                 unsigned long lval;
2082                 if (val < 0) {
2083                         *negp = -1;
2084                         lval = (unsigned long)-val;
2085                 } else {
2086                         *negp = 0;
2087                         lval = (unsigned long)val;
2088                 }
2089                 *lvalp = jiffies_to_clock_t(lval);
2090         }
2091         return 0;
2092 }
2093
2094 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2095                                             int *valp,
2096                                             int write, void *data)
2097 {
2098         if (write) {
2099                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2100         } else {
2101                 int val = *valp;
2102                 unsigned long lval;
2103                 if (val < 0) {
2104                         *negp = -1;
2105                         lval = (unsigned long)-val;
2106                 } else {
2107                         *negp = 0;
2108                         lval = (unsigned long)val;
2109                 }
2110                 *lvalp = jiffies_to_msecs(lval);
2111         }
2112         return 0;
2113 }
2114
2115 /**
2116  * proc_dointvec_jiffies - read a vector of integers as seconds
2117  * @table: the sysctl table
2118  * @write: %TRUE if this is a write to the sysctl file
2119  * @filp: the file structure
2120  * @buffer: the user buffer
2121  * @lenp: the size of the user buffer
2122  * @ppos: file position
2123  *
2124  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2125  * values from/to the user buffer, treated as an ASCII string. 
2126  * The values read are assumed to be in seconds, and are converted into
2127  * jiffies.
2128  *
2129  * Returns 0 on success.
2130  */
2131 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2132                           void __user *buffer, size_t *lenp, loff_t *ppos)
2133 {
2134     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2135                             do_proc_dointvec_jiffies_conv,NULL);
2136 }
2137
2138 /**
2139  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2140  * @table: the sysctl table
2141  * @write: %TRUE if this is a write to the sysctl file
2142  * @filp: the file structure
2143  * @buffer: the user buffer
2144  * @lenp: the size of the user buffer
2145  * @ppos: pointer to the file position
2146  *
2147  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2148  * values from/to the user buffer, treated as an ASCII string. 
2149  * The values read are assumed to be in 1/USER_HZ seconds, and 
2150  * are converted into jiffies.
2151  *
2152  * Returns 0 on success.
2153  */
2154 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2155                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2156 {
2157     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2158                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2159 }
2160
2161 /**
2162  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2163  * @table: the sysctl table
2164  * @write: %TRUE if this is a write to the sysctl file
2165  * @filp: the file structure
2166  * @buffer: the user buffer
2167  * @lenp: the size of the user buffer
2168  * @ppos: file position
2169  * @ppos: the current position in the file
2170  *
2171  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2172  * values from/to the user buffer, treated as an ASCII string. 
2173  * The values read are assumed to be in 1/1000 seconds, and 
2174  * are converted into jiffies.
2175  *
2176  * Returns 0 on success.
2177  */
2178 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2179                              void __user *buffer, size_t *lenp, loff_t *ppos)
2180 {
2181         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2182                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2183 }
2184
2185 static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
2186                            void __user *buffer, size_t *lenp, loff_t *ppos)
2187 {
2188         struct pid *new_pid;
2189         pid_t tmp;
2190         int r;
2191
2192         tmp = pid_nr(cad_pid);
2193
2194         r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2195                                lenp, ppos, NULL, NULL);
2196         if (r || !write)
2197                 return r;
2198
2199         new_pid = find_get_pid(tmp);
2200         if (!new_pid)
2201                 return -ESRCH;
2202
2203         put_pid(xchg(&cad_pid, new_pid));
2204         return 0;
2205 }
2206
2207 #else /* CONFIG_PROC_FS */
2208
2209 int proc_dostring(ctl_table *table, int write, struct file *filp,
2210                   void __user *buffer, size_t *lenp, loff_t *ppos)
2211 {
2212         return -ENOSYS;
2213 }
2214
2215 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2216                   void __user *buffer, size_t *lenp, loff_t *ppos)
2217 {
2218         return -ENOSYS;
2219 }
2220
2221 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2222                         void __user *buffer, size_t *lenp, loff_t *ppos)
2223 {
2224         return -ENOSYS;
2225 }
2226
2227 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2228                     void __user *buffer, size_t *lenp, loff_t *ppos)
2229 {
2230         return -ENOSYS;
2231 }
2232
2233 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2234                     void __user *buffer, size_t *lenp, loff_t *ppos)
2235 {
2236         return -ENOSYS;
2237 }
2238
2239 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2240                     void __user *buffer, size_t *lenp, loff_t *ppos)
2241 {
2242         return -ENOSYS;
2243 }
2244
2245 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2246                              void __user *buffer, size_t *lenp, loff_t *ppos)
2247 {
2248         return -ENOSYS;
2249 }
2250
2251 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2252                     void __user *buffer, size_t *lenp, loff_t *ppos)
2253 {
2254         return -ENOSYS;
2255 }
2256
2257 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2258                                       struct file *filp,
2259                                       void __user *buffer,
2260                                       size_t *lenp, loff_t *ppos)
2261 {
2262     return -ENOSYS;
2263 }
2264
2265
2266 #endif /* CONFIG_PROC_FS */
2267
2268
2269 #ifdef CONFIG_SYSCTL_SYSCALL
2270 /*
2271  * General sysctl support routines 
2272  */
2273
2274 /* The generic string strategy routine: */
2275 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2276                   void __user *oldval, size_t __user *oldlenp,
2277                   void __user *newval, size_t newlen)
2278 {
2279         if (!table->data || !table->maxlen) 
2280                 return -ENOTDIR;
2281         
2282         if (oldval && oldlenp) {
2283                 size_t bufsize;
2284                 if (get_user(bufsize, oldlenp))
2285                         return -EFAULT;
2286                 if (bufsize) {
2287                         size_t len = strlen(table->data), copied;
2288
2289                         /* This shouldn't trigger for a well-formed sysctl */
2290                         if (len > table->maxlen)
2291                                 len = table->maxlen;
2292
2293                         /* Copy up to a max of bufsize-1 bytes of the string */
2294                         copied = (len >= bufsize) ? bufsize - 1 : len;
2295
2296                         if (copy_to_user(oldval, table->data, copied) ||
2297                             put_user(0, (char __user *)(oldval + copied)))
2298                                 return -EFAULT;
2299                         if (put_user(len, oldlenp))
2300                                 return -EFAULT;
2301                 }
2302         }
2303         if (newval && newlen) {
2304                 size_t len = newlen;
2305                 if (len > table->maxlen)
2306                         len = table->maxlen;
2307                 if(copy_from_user(table->data, newval, len))
2308                         return -EFAULT;
2309                 if (len == table->maxlen)
2310                         len--;
2311                 ((char *) table->data)[len] = 0;
2312         }
2313         return 1;
2314 }
2315
2316 /*
2317  * This function makes sure that all of the integers in the vector
2318  * are between the minimum and maximum values given in the arrays
2319  * table->extra1 and table->extra2, respectively.
2320  */
2321 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2322                 void __user *oldval, size_t __user *oldlenp,
2323                 void __user *newval, size_t newlen)
2324 {
2325
2326         if (newval && newlen) {
2327                 int __user *vec = (int __user *) newval;
2328                 int *min = (int *) table->extra1;
2329                 int *max = (int *) table->extra2;
2330                 size_t length;
2331                 int i;
2332
2333                 if (newlen % sizeof(int) != 0)
2334                         return -EINVAL;
2335
2336                 if (!table->extra1 && !table->extra2)
2337                         return 0;
2338
2339                 if (newlen > table->maxlen)
2340                         newlen = table->maxlen;
2341                 length = newlen / sizeof(int);
2342
2343                 for (i = 0; i < length; i++) {
2344                         int value;
2345                         if (get_user(value, vec + i))
2346                                 return -EFAULT;
2347                         if (min && value < min[i])
2348                                 return -EINVAL;
2349                         if (max && value > max[i])
2350                                 return -EINVAL;
2351                 }
2352         }
2353         return 0;
2354 }
2355
2356 /* Strategy function to convert jiffies to seconds */ 
2357 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2358                 void __user *oldval, size_t __user *oldlenp,
2359                 void __user *newval, size_t newlen)
2360 {
2361         if (oldval && oldlenp) {
2362                 size_t olen;
2363
2364                 if (get_user(olen, oldlenp))
2365                         return -EFAULT;
2366                 if (olen) {
2367                         int val;
2368
2369                         if (olen < sizeof(int))
2370                                 return -EINVAL;
2371
2372                         val = *(int *)(table->data) / HZ;
2373                         if (put_user(val, (int __user *)oldval))
2374                                 return -EFAULT;
2375                         if (put_user(sizeof(int), oldlenp))
2376                                 return -EFAULT;
2377                 }
2378         }
2379         if (newval && newlen) { 
2380                 int new;
2381                 if (newlen != sizeof(int))
2382                         return -EINVAL; 
2383                 if (get_user(new, (int __user *)newval))
2384                         return -EFAULT;
2385                 *(int *)(table->data) = new*HZ; 
2386         }
2387         return 1;
2388 }
2389
2390 /* Strategy function to convert jiffies to seconds */ 
2391 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2392                 void __user *oldval, size_t __user *oldlenp,
2393                 void __user *newval, size_t newlen)
2394 {
2395         if (oldval && oldlenp) {
2396                 size_t olen;
2397
2398                 if (get_user(olen, oldlenp))
2399                         return -EFAULT;
2400                 if (olen) {
2401                         int val;
2402
2403                         if (olen < sizeof(int))
2404                                 return -EINVAL;
2405
2406                         val = jiffies_to_msecs(*(int *)(table->data));
2407                         if (put_user(val, (int __user *)oldval))
2408                                 return -EFAULT;
2409                         if (put_user(sizeof(int), oldlenp))
2410                                 return -EFAULT;
2411                 }
2412         }
2413         if (newval && newlen) { 
2414                 int new;
2415                 if (newlen != sizeof(int))
2416                         return -EINVAL; 
2417                 if (get_user(new, (int __user *)newval))
2418                         return -EFAULT;
2419                 *(int *)(table->data) = msecs_to_jiffies(new);
2420         }
2421         return 1;
2422 }
2423
2424
2425
2426 #else /* CONFIG_SYSCTL_SYSCALL */
2427
2428
2429 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2430 {
2431         static int msg_count;
2432         struct __sysctl_args tmp;
2433         int name[CTL_MAXNAME];
2434         int i;
2435
2436         /* Read in the sysctl name for better debug message logging */
2437         if (copy_from_user(&tmp, args, sizeof(tmp)))
2438                 return -EFAULT;
2439         if (tmp.nlen <= 0 || tmp.nlen >= CTL_MAXNAME)
2440                 return -ENOTDIR;
2441         for (i = 0; i < tmp.nlen; i++)
2442                 if (get_user(name[i], tmp.name + i))
2443                         return -EFAULT;
2444
2445         /* Ignore accesses to kernel.version */
2446         if ((tmp.nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
2447                 goto out;
2448
2449         if (msg_count < 5) {
2450                 msg_count++;
2451                 printk(KERN_INFO
2452                         "warning: process `%s' used the removed sysctl "
2453                         "system call with ", current->comm);
2454                 for (i = 0; i < tmp.nlen; i++)
2455                         printk("%d.", name[i]);
2456                 printk("\n");
2457         }
2458 out:
2459         return -ENOSYS;
2460 }
2461
2462 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2463                   void __user *oldval, size_t __user *oldlenp,
2464                   void __user *newval, size_t newlen)
2465 {
2466         return -ENOSYS;
2467 }
2468
2469 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2470                 void __user *oldval, size_t __user *oldlenp,
2471                 void __user *newval, size_t newlen)
2472 {
2473         return -ENOSYS;
2474 }
2475
2476 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2477                 void __user *oldval, size_t __user *oldlenp,
2478                 void __user *newval, size_t newlen)
2479 {
2480         return -ENOSYS;
2481 }
2482
2483 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2484                 void __user *oldval, size_t __user *oldlenp,
2485                 void __user *newval, size_t newlen)
2486 {
2487         return -ENOSYS;
2488 }
2489
2490 #endif /* CONFIG_SYSCTL_SYSCALL */
2491
2492 /*
2493  * No sense putting this after each symbol definition, twice,
2494  * exception granted :-)
2495  */
2496 EXPORT_SYMBOL(proc_dointvec);
2497 EXPORT_SYMBOL(proc_dointvec_jiffies);
2498 EXPORT_SYMBOL(proc_dointvec_minmax);
2499 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2500 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2501 EXPORT_SYMBOL(proc_dostring);
2502 EXPORT_SYMBOL(proc_doulongvec_minmax);
2503 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2504 EXPORT_SYMBOL(register_sysctl_table);
2505 EXPORT_SYMBOL(sysctl_intvec);
2506 EXPORT_SYMBOL(sysctl_jiffies);
2507 EXPORT_SYMBOL(sysctl_ms_jiffies);
2508 EXPORT_SYMBOL(sysctl_string);
2509 EXPORT_SYMBOL(unregister_sysctl_table);