[PATCH] inotify (1/5): split kernel API from userspace support
[linux-2.6.git] / kernel / sysctl.c
1 /*
2  * sysctl.c: General linux system control interface
3  *
4  * Begun 24 March 1995, Stephen Tweedie
5  * Added /proc support, Dec 1995
6  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
7  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
8  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
9  * Dynamic registration fixes, Stephen Tweedie.
10  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
11  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
12  *  Horn.
13  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
14  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
15  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
16  *  Wendling.
17  * The list_for_each() macro wasn't appropriate for the sysctl loop.
18  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
19  */
20
21 #include <linux/config.h>
22 #include <linux/module.h>
23 #include <linux/mm.h>
24 #include <linux/swap.h>
25 #include <linux/slab.h>
26 #include <linux/sysctl.h>
27 #include <linux/proc_fs.h>
28 #include <linux/capability.h>
29 #include <linux/ctype.h>
30 #include <linux/utsname.h>
31 #include <linux/capability.h>
32 #include <linux/smp_lock.h>
33 #include <linux/init.h>
34 #include <linux/kernel.h>
35 #include <linux/kobject.h>
36 #include <linux/net.h>
37 #include <linux/sysrq.h>
38 #include <linux/highuid.h>
39 #include <linux/writeback.h>
40 #include <linux/hugetlb.h>
41 #include <linux/security.h>
42 #include <linux/initrd.h>
43 #include <linux/times.h>
44 #include <linux/limits.h>
45 #include <linux/dcache.h>
46 #include <linux/syscalls.h>
47 #include <linux/nfs_fs.h>
48 #include <linux/acpi.h>
49
50 #include <asm/uaccess.h>
51 #include <asm/processor.h>
52
53 extern int proc_nr_files(ctl_table *table, int write, struct file *filp,
54                      void __user *buffer, size_t *lenp, loff_t *ppos);
55
56 #if defined(CONFIG_SYSCTL)
57
58 /* External variables not in a header file. */
59 extern int C_A_D;
60 extern int sysctl_overcommit_memory;
61 extern int sysctl_overcommit_ratio;
62 extern int max_threads;
63 extern int sysrq_enabled;
64 extern int core_uses_pid;
65 extern int suid_dumpable;
66 extern char core_pattern[];
67 extern int cad_pid;
68 extern int pid_max;
69 extern int min_free_kbytes;
70 extern int printk_ratelimit_jiffies;
71 extern int printk_ratelimit_burst;
72 extern int pid_max_min, pid_max_max;
73 extern int sysctl_drop_caches;
74 extern int percpu_pagelist_fraction;
75
76 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
77 int unknown_nmi_panic;
78 extern int proc_unknown_nmi_panic(ctl_table *, int, struct file *,
79                                   void __user *, size_t *, loff_t *);
80 #endif
81
82 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
83 static int maxolduid = 65535;
84 static int minolduid;
85 static int min_percpu_pagelist_fract = 8;
86
87 static int ngroups_max = NGROUPS_MAX;
88
89 #ifdef CONFIG_KMOD
90 extern char modprobe_path[];
91 #endif
92 #ifdef CONFIG_CHR_DEV_SG
93 extern int sg_big_buff;
94 #endif
95 #ifdef CONFIG_SYSVIPC
96 extern size_t shm_ctlmax;
97 extern size_t shm_ctlall;
98 extern int shm_ctlmni;
99 extern int msg_ctlmax;
100 extern int msg_ctlmnb;
101 extern int msg_ctlmni;
102 extern int sem_ctls[];
103 #endif
104
105 #ifdef __sparc__
106 extern char reboot_command [];
107 extern int stop_a_enabled;
108 extern int scons_pwroff;
109 #endif
110
111 #ifdef __hppa__
112 extern int pwrsw_enabled;
113 extern int unaligned_enabled;
114 #endif
115
116 #ifdef CONFIG_S390
117 #ifdef CONFIG_MATHEMU
118 extern int sysctl_ieee_emulation_warnings;
119 #endif
120 extern int sysctl_userprocess_debug;
121 extern int spin_retry;
122 #endif
123
124 extern int sysctl_hz_timer;
125
126 #ifdef CONFIG_BSD_PROCESS_ACCT
127 extern int acct_parm[];
128 #endif
129
130 #ifdef CONFIG_IA64
131 extern int no_unaligned_warning;
132 #endif
133
134 static int parse_table(int __user *, int, void __user *, size_t __user *, void __user *, size_t,
135                        ctl_table *, void **);
136 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
137                   void __user *buffer, size_t *lenp, loff_t *ppos);
138
139 static ctl_table root_table[];
140 static struct ctl_table_header root_table_header =
141         { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
142
143 static ctl_table kern_table[];
144 static ctl_table vm_table[];
145 static ctl_table proc_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 /* /proc declarations: */
162
163 #ifdef CONFIG_PROC_FS
164
165 static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
166 static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
167 static int proc_opensys(struct inode *, struct file *);
168
169 struct file_operations proc_sys_file_operations = {
170         .open           = proc_opensys,
171         .read           = proc_readsys,
172         .write          = proc_writesys,
173 };
174
175 extern struct proc_dir_entry *proc_sys_root;
176
177 static void register_proc_table(ctl_table *, struct proc_dir_entry *, void *);
178 static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
179 #endif
180
181 /* The default sysctl tables: */
182
183 static ctl_table root_table[] = {
184         {
185                 .ctl_name       = CTL_KERN,
186                 .procname       = "kernel",
187                 .mode           = 0555,
188                 .child          = kern_table,
189         },
190         {
191                 .ctl_name       = CTL_VM,
192                 .procname       = "vm",
193                 .mode           = 0555,
194                 .child          = vm_table,
195         },
196 #ifdef CONFIG_NET
197         {
198                 .ctl_name       = CTL_NET,
199                 .procname       = "net",
200                 .mode           = 0555,
201                 .child          = net_table,
202         },
203 #endif
204         {
205                 .ctl_name       = CTL_PROC,
206                 .procname       = "proc",
207                 .mode           = 0555,
208                 .child          = proc_table,
209         },
210         {
211                 .ctl_name       = CTL_FS,
212                 .procname       = "fs",
213                 .mode           = 0555,
214                 .child          = fs_table,
215         },
216         {
217                 .ctl_name       = CTL_DEBUG,
218                 .procname       = "debug",
219                 .mode           = 0555,
220                 .child          = debug_table,
221         },
222         {
223                 .ctl_name       = CTL_DEV,
224                 .procname       = "dev",
225                 .mode           = 0555,
226                 .child          = dev_table,
227         },
228
229         { .ctl_name = 0 }
230 };
231
232 static ctl_table kern_table[] = {
233         {
234                 .ctl_name       = KERN_OSTYPE,
235                 .procname       = "ostype",
236                 .data           = system_utsname.sysname,
237                 .maxlen         = sizeof(system_utsname.sysname),
238                 .mode           = 0444,
239                 .proc_handler   = &proc_doutsstring,
240                 .strategy       = &sysctl_string,
241         },
242         {
243                 .ctl_name       = KERN_OSRELEASE,
244                 .procname       = "osrelease",
245                 .data           = system_utsname.release,
246                 .maxlen         = sizeof(system_utsname.release),
247                 .mode           = 0444,
248                 .proc_handler   = &proc_doutsstring,
249                 .strategy       = &sysctl_string,
250         },
251         {
252                 .ctl_name       = KERN_VERSION,
253                 .procname       = "version",
254                 .data           = system_utsname.version,
255                 .maxlen         = sizeof(system_utsname.version),
256                 .mode           = 0444,
257                 .proc_handler   = &proc_doutsstring,
258                 .strategy       = &sysctl_string,
259         },
260         {
261                 .ctl_name       = KERN_NODENAME,
262                 .procname       = "hostname",
263                 .data           = system_utsname.nodename,
264                 .maxlen         = sizeof(system_utsname.nodename),
265                 .mode           = 0644,
266                 .proc_handler   = &proc_doutsstring,
267                 .strategy       = &sysctl_string,
268         },
269         {
270                 .ctl_name       = KERN_DOMAINNAME,
271                 .procname       = "domainname",
272                 .data           = system_utsname.domainname,
273                 .maxlen         = sizeof(system_utsname.domainname),
274                 .mode           = 0644,
275                 .proc_handler   = &proc_doutsstring,
276                 .strategy       = &sysctl_string,
277         },
278         {
279                 .ctl_name       = KERN_PANIC,
280                 .procname       = "panic",
281                 .data           = &panic_timeout,
282                 .maxlen         = sizeof(int),
283                 .mode           = 0644,
284                 .proc_handler   = &proc_dointvec,
285         },
286         {
287                 .ctl_name       = KERN_CORE_USES_PID,
288                 .procname       = "core_uses_pid",
289                 .data           = &core_uses_pid,
290                 .maxlen         = sizeof(int),
291                 .mode           = 0644,
292                 .proc_handler   = &proc_dointvec,
293         },
294         {
295                 .ctl_name       = KERN_CORE_PATTERN,
296                 .procname       = "core_pattern",
297                 .data           = core_pattern,
298                 .maxlen         = 64,
299                 .mode           = 0644,
300                 .proc_handler   = &proc_dostring,
301                 .strategy       = &sysctl_string,
302         },
303         {
304                 .ctl_name       = KERN_TAINTED,
305                 .procname       = "tainted",
306                 .data           = &tainted,
307                 .maxlen         = sizeof(int),
308                 .mode           = 0444,
309                 .proc_handler   = &proc_dointvec,
310         },
311         {
312                 .ctl_name       = KERN_CAP_BSET,
313                 .procname       = "cap-bound",
314                 .data           = &cap_bset,
315                 .maxlen         = sizeof(kernel_cap_t),
316                 .mode           = 0600,
317                 .proc_handler   = &proc_dointvec_bset,
318         },
319 #ifdef CONFIG_BLK_DEV_INITRD
320         {
321                 .ctl_name       = KERN_REALROOTDEV,
322                 .procname       = "real-root-dev",
323                 .data           = &real_root_dev,
324                 .maxlen         = sizeof(int),
325                 .mode           = 0644,
326                 .proc_handler   = &proc_dointvec,
327         },
328 #endif
329 #ifdef __sparc__
330         {
331                 .ctl_name       = KERN_SPARC_REBOOT,
332                 .procname       = "reboot-cmd",
333                 .data           = reboot_command,
334                 .maxlen         = 256,
335                 .mode           = 0644,
336                 .proc_handler   = &proc_dostring,
337                 .strategy       = &sysctl_string,
338         },
339         {
340                 .ctl_name       = KERN_SPARC_STOP_A,
341                 .procname       = "stop-a",
342                 .data           = &stop_a_enabled,
343                 .maxlen         = sizeof (int),
344                 .mode           = 0644,
345                 .proc_handler   = &proc_dointvec,
346         },
347         {
348                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
349                 .procname       = "scons-poweroff",
350                 .data           = &scons_pwroff,
351                 .maxlen         = sizeof (int),
352                 .mode           = 0644,
353                 .proc_handler   = &proc_dointvec,
354         },
355 #endif
356 #ifdef __hppa__
357         {
358                 .ctl_name       = KERN_HPPA_PWRSW,
359                 .procname       = "soft-power",
360                 .data           = &pwrsw_enabled,
361                 .maxlen         = sizeof (int),
362                 .mode           = 0644,
363                 .proc_handler   = &proc_dointvec,
364         },
365         {
366                 .ctl_name       = KERN_HPPA_UNALIGNED,
367                 .procname       = "unaligned-trap",
368                 .data           = &unaligned_enabled,
369                 .maxlen         = sizeof (int),
370                 .mode           = 0644,
371                 .proc_handler   = &proc_dointvec,
372         },
373 #endif
374         {
375                 .ctl_name       = KERN_CTLALTDEL,
376                 .procname       = "ctrl-alt-del",
377                 .data           = &C_A_D,
378                 .maxlen         = sizeof(int),
379                 .mode           = 0644,
380                 .proc_handler   = &proc_dointvec,
381         },
382         {
383                 .ctl_name       = KERN_PRINTK,
384                 .procname       = "printk",
385                 .data           = &console_loglevel,
386                 .maxlen         = 4*sizeof(int),
387                 .mode           = 0644,
388                 .proc_handler   = &proc_dointvec,
389         },
390 #ifdef CONFIG_KMOD
391         {
392                 .ctl_name       = KERN_MODPROBE,
393                 .procname       = "modprobe",
394                 .data           = &modprobe_path,
395                 .maxlen         = KMOD_PATH_LEN,
396                 .mode           = 0644,
397                 .proc_handler   = &proc_dostring,
398                 .strategy       = &sysctl_string,
399         },
400 #endif
401 #ifdef CONFIG_HOTPLUG
402         {
403                 .ctl_name       = KERN_HOTPLUG,
404                 .procname       = "hotplug",
405                 .data           = &uevent_helper,
406                 .maxlen         = UEVENT_HELPER_PATH_LEN,
407                 .mode           = 0644,
408                 .proc_handler   = &proc_dostring,
409                 .strategy       = &sysctl_string,
410         },
411 #endif
412 #ifdef CONFIG_CHR_DEV_SG
413         {
414                 .ctl_name       = KERN_SG_BIG_BUFF,
415                 .procname       = "sg-big-buff",
416                 .data           = &sg_big_buff,
417                 .maxlen         = sizeof (int),
418                 .mode           = 0444,
419                 .proc_handler   = &proc_dointvec,
420         },
421 #endif
422 #ifdef CONFIG_BSD_PROCESS_ACCT
423         {
424                 .ctl_name       = KERN_ACCT,
425                 .procname       = "acct",
426                 .data           = &acct_parm,
427                 .maxlen         = 3*sizeof(int),
428                 .mode           = 0644,
429                 .proc_handler   = &proc_dointvec,
430         },
431 #endif
432 #ifdef CONFIG_SYSVIPC
433         {
434                 .ctl_name       = KERN_SHMMAX,
435                 .procname       = "shmmax",
436                 .data           = &shm_ctlmax,
437                 .maxlen         = sizeof (size_t),
438                 .mode           = 0644,
439                 .proc_handler   = &proc_doulongvec_minmax,
440         },
441         {
442                 .ctl_name       = KERN_SHMALL,
443                 .procname       = "shmall",
444                 .data           = &shm_ctlall,
445                 .maxlen         = sizeof (size_t),
446                 .mode           = 0644,
447                 .proc_handler   = &proc_doulongvec_minmax,
448         },
449         {
450                 .ctl_name       = KERN_SHMMNI,
451                 .procname       = "shmmni",
452                 .data           = &shm_ctlmni,
453                 .maxlen         = sizeof (int),
454                 .mode           = 0644,
455                 .proc_handler   = &proc_dointvec,
456         },
457         {
458                 .ctl_name       = KERN_MSGMAX,
459                 .procname       = "msgmax",
460                 .data           = &msg_ctlmax,
461                 .maxlen         = sizeof (int),
462                 .mode           = 0644,
463                 .proc_handler   = &proc_dointvec,
464         },
465         {
466                 .ctl_name       = KERN_MSGMNI,
467                 .procname       = "msgmni",
468                 .data           = &msg_ctlmni,
469                 .maxlen         = sizeof (int),
470                 .mode           = 0644,
471                 .proc_handler   = &proc_dointvec,
472         },
473         {
474                 .ctl_name       = KERN_MSGMNB,
475                 .procname       =  "msgmnb",
476                 .data           = &msg_ctlmnb,
477                 .maxlen         = sizeof (int),
478                 .mode           = 0644,
479                 .proc_handler   = &proc_dointvec,
480         },
481         {
482                 .ctl_name       = KERN_SEM,
483                 .procname       = "sem",
484                 .data           = &sem_ctls,
485                 .maxlen         = 4*sizeof (int),
486                 .mode           = 0644,
487                 .proc_handler   = &proc_dointvec,
488         },
489 #endif
490 #ifdef CONFIG_MAGIC_SYSRQ
491         {
492                 .ctl_name       = KERN_SYSRQ,
493                 .procname       = "sysrq",
494                 .data           = &sysrq_enabled,
495                 .maxlen         = sizeof (int),
496                 .mode           = 0644,
497                 .proc_handler   = &proc_dointvec,
498         },
499 #endif
500         {
501                 .ctl_name       = KERN_CADPID,
502                 .procname       = "cad_pid",
503                 .data           = &cad_pid,
504                 .maxlen         = sizeof (int),
505                 .mode           = 0600,
506                 .proc_handler   = &proc_dointvec,
507         },
508         {
509                 .ctl_name       = KERN_MAX_THREADS,
510                 .procname       = "threads-max",
511                 .data           = &max_threads,
512                 .maxlen         = sizeof(int),
513                 .mode           = 0644,
514                 .proc_handler   = &proc_dointvec,
515         },
516         {
517                 .ctl_name       = KERN_RANDOM,
518                 .procname       = "random",
519                 .mode           = 0555,
520                 .child          = random_table,
521         },
522 #ifdef CONFIG_UNIX98_PTYS
523         {
524                 .ctl_name       = KERN_PTY,
525                 .procname       = "pty",
526                 .mode           = 0555,
527                 .child          = pty_table,
528         },
529 #endif
530         {
531                 .ctl_name       = KERN_OVERFLOWUID,
532                 .procname       = "overflowuid",
533                 .data           = &overflowuid,
534                 .maxlen         = sizeof(int),
535                 .mode           = 0644,
536                 .proc_handler   = &proc_dointvec_minmax,
537                 .strategy       = &sysctl_intvec,
538                 .extra1         = &minolduid,
539                 .extra2         = &maxolduid,
540         },
541         {
542                 .ctl_name       = KERN_OVERFLOWGID,
543                 .procname       = "overflowgid",
544                 .data           = &overflowgid,
545                 .maxlen         = sizeof(int),
546                 .mode           = 0644,
547                 .proc_handler   = &proc_dointvec_minmax,
548                 .strategy       = &sysctl_intvec,
549                 .extra1         = &minolduid,
550                 .extra2         = &maxolduid,
551         },
552 #ifdef CONFIG_S390
553 #ifdef CONFIG_MATHEMU
554         {
555                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
556                 .procname       = "ieee_emulation_warnings",
557                 .data           = &sysctl_ieee_emulation_warnings,
558                 .maxlen         = sizeof(int),
559                 .mode           = 0644,
560                 .proc_handler   = &proc_dointvec,
561         },
562 #endif
563 #ifdef CONFIG_NO_IDLE_HZ
564         {
565                 .ctl_name       = KERN_HZ_TIMER,
566                 .procname       = "hz_timer",
567                 .data           = &sysctl_hz_timer,
568                 .maxlen         = sizeof(int),
569                 .mode           = 0644,
570                 .proc_handler   = &proc_dointvec,
571         },
572 #endif
573         {
574                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
575                 .procname       = "userprocess_debug",
576                 .data           = &sysctl_userprocess_debug,
577                 .maxlen         = sizeof(int),
578                 .mode           = 0644,
579                 .proc_handler   = &proc_dointvec,
580         },
581 #endif
582         {
583                 .ctl_name       = KERN_PIDMAX,
584                 .procname       = "pid_max",
585                 .data           = &pid_max,
586                 .maxlen         = sizeof (int),
587                 .mode           = 0644,
588                 .proc_handler   = &proc_dointvec_minmax,
589                 .strategy       = sysctl_intvec,
590                 .extra1         = &pid_max_min,
591                 .extra2         = &pid_max_max,
592         },
593         {
594                 .ctl_name       = KERN_PANIC_ON_OOPS,
595                 .procname       = "panic_on_oops",
596                 .data           = &panic_on_oops,
597                 .maxlen         = sizeof(int),
598                 .mode           = 0644,
599                 .proc_handler   = &proc_dointvec,
600         },
601         {
602                 .ctl_name       = KERN_PRINTK_RATELIMIT,
603                 .procname       = "printk_ratelimit",
604                 .data           = &printk_ratelimit_jiffies,
605                 .maxlen         = sizeof(int),
606                 .mode           = 0644,
607                 .proc_handler   = &proc_dointvec_jiffies,
608                 .strategy       = &sysctl_jiffies,
609         },
610         {
611                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
612                 .procname       = "printk_ratelimit_burst",
613                 .data           = &printk_ratelimit_burst,
614                 .maxlen         = sizeof(int),
615                 .mode           = 0644,
616                 .proc_handler   = &proc_dointvec,
617         },
618         {
619                 .ctl_name       = KERN_NGROUPS_MAX,
620                 .procname       = "ngroups_max",
621                 .data           = &ngroups_max,
622                 .maxlen         = sizeof (int),
623                 .mode           = 0444,
624                 .proc_handler   = &proc_dointvec,
625         },
626 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
627         {
628                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
629                 .procname       = "unknown_nmi_panic",
630                 .data           = &unknown_nmi_panic,
631                 .maxlen         = sizeof (int),
632                 .mode           = 0644,
633                 .proc_handler   = &proc_unknown_nmi_panic,
634         },
635 #endif
636 #if defined(CONFIG_X86)
637         {
638                 .ctl_name       = KERN_BOOTLOADER_TYPE,
639                 .procname       = "bootloader_type",
640                 .data           = &bootloader_type,
641                 .maxlen         = sizeof (int),
642                 .mode           = 0444,
643                 .proc_handler   = &proc_dointvec,
644         },
645 #endif
646 #if defined(CONFIG_MMU)
647         {
648                 .ctl_name       = KERN_RANDOMIZE,
649                 .procname       = "randomize_va_space",
650                 .data           = &randomize_va_space,
651                 .maxlen         = sizeof(int),
652                 .mode           = 0644,
653                 .proc_handler   = &proc_dointvec,
654         },
655 #endif
656 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
657         {
658                 .ctl_name       = KERN_SPIN_RETRY,
659                 .procname       = "spin_retry",
660                 .data           = &spin_retry,
661                 .maxlen         = sizeof (int),
662                 .mode           = 0644,
663                 .proc_handler   = &proc_dointvec,
664         },
665 #endif
666 #ifdef CONFIG_ACPI_SLEEP
667         {
668                 .ctl_name       = KERN_ACPI_VIDEO_FLAGS,
669                 .procname       = "acpi_video_flags",
670                 .data           = &acpi_video_flags,
671                 .maxlen         = sizeof (unsigned long),
672                 .mode           = 0644,
673                 .proc_handler   = &proc_doulongvec_minmax,
674         },
675 #endif
676 #ifdef CONFIG_IA64
677         {
678                 .ctl_name       = KERN_IA64_UNALIGNED,
679                 .procname       = "ignore-unaligned-usertrap",
680                 .data           = &no_unaligned_warning,
681                 .maxlen         = sizeof (int),
682                 .mode           = 0644,
683                 .proc_handler   = &proc_dointvec,
684         },
685 #endif
686         { .ctl_name = 0 }
687 };
688
689 /* Constants for minimum and maximum testing in vm_table.
690    We use these as one-element integer vectors. */
691 static int zero;
692 static int one_hundred = 100;
693
694
695 static ctl_table vm_table[] = {
696         {
697                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
698                 .procname       = "overcommit_memory",
699                 .data           = &sysctl_overcommit_memory,
700                 .maxlen         = sizeof(sysctl_overcommit_memory),
701                 .mode           = 0644,
702                 .proc_handler   = &proc_dointvec,
703         },
704         {
705                 .ctl_name       = VM_OVERCOMMIT_RATIO,
706                 .procname       = "overcommit_ratio",
707                 .data           = &sysctl_overcommit_ratio,
708                 .maxlen         = sizeof(sysctl_overcommit_ratio),
709                 .mode           = 0644,
710                 .proc_handler   = &proc_dointvec,
711         },
712         {
713                 .ctl_name       = VM_PAGE_CLUSTER,
714                 .procname       = "page-cluster", 
715                 .data           = &page_cluster,
716                 .maxlen         = sizeof(int),
717                 .mode           = 0644,
718                 .proc_handler   = &proc_dointvec,
719         },
720         {
721                 .ctl_name       = VM_DIRTY_BACKGROUND,
722                 .procname       = "dirty_background_ratio",
723                 .data           = &dirty_background_ratio,
724                 .maxlen         = sizeof(dirty_background_ratio),
725                 .mode           = 0644,
726                 .proc_handler   = &proc_dointvec_minmax,
727                 .strategy       = &sysctl_intvec,
728                 .extra1         = &zero,
729                 .extra2         = &one_hundred,
730         },
731         {
732                 .ctl_name       = VM_DIRTY_RATIO,
733                 .procname       = "dirty_ratio",
734                 .data           = &vm_dirty_ratio,
735                 .maxlen         = sizeof(vm_dirty_ratio),
736                 .mode           = 0644,
737                 .proc_handler   = &proc_dointvec_minmax,
738                 .strategy       = &sysctl_intvec,
739                 .extra1         = &zero,
740                 .extra2         = &one_hundred,
741         },
742         {
743                 .ctl_name       = VM_DIRTY_WB_CS,
744                 .procname       = "dirty_writeback_centisecs",
745                 .data           = &dirty_writeback_interval,
746                 .maxlen         = sizeof(dirty_writeback_interval),
747                 .mode           = 0644,
748                 .proc_handler   = &dirty_writeback_centisecs_handler,
749         },
750         {
751                 .ctl_name       = VM_DIRTY_EXPIRE_CS,
752                 .procname       = "dirty_expire_centisecs",
753                 .data           = &dirty_expire_interval,
754                 .maxlen         = sizeof(dirty_expire_interval),
755                 .mode           = 0644,
756                 .proc_handler   = &proc_dointvec_userhz_jiffies,
757         },
758         {
759                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
760                 .procname       = "nr_pdflush_threads",
761                 .data           = &nr_pdflush_threads,
762                 .maxlen         = sizeof nr_pdflush_threads,
763                 .mode           = 0444 /* read-only*/,
764                 .proc_handler   = &proc_dointvec,
765         },
766         {
767                 .ctl_name       = VM_SWAPPINESS,
768                 .procname       = "swappiness",
769                 .data           = &vm_swappiness,
770                 .maxlen         = sizeof(vm_swappiness),
771                 .mode           = 0644,
772                 .proc_handler   = &proc_dointvec_minmax,
773                 .strategy       = &sysctl_intvec,
774                 .extra1         = &zero,
775                 .extra2         = &one_hundred,
776         },
777 #ifdef CONFIG_HUGETLB_PAGE
778          {
779                 .ctl_name       = VM_HUGETLB_PAGES,
780                 .procname       = "nr_hugepages",
781                 .data           = &max_huge_pages,
782                 .maxlen         = sizeof(unsigned long),
783                 .mode           = 0644,
784                 .proc_handler   = &hugetlb_sysctl_handler,
785                 .extra1         = (void *)&hugetlb_zero,
786                 .extra2         = (void *)&hugetlb_infinity,
787          },
788          {
789                 .ctl_name       = VM_HUGETLB_GROUP,
790                 .procname       = "hugetlb_shm_group",
791                 .data           = &sysctl_hugetlb_shm_group,
792                 .maxlen         = sizeof(gid_t),
793                 .mode           = 0644,
794                 .proc_handler   = &proc_dointvec,
795          },
796 #endif
797         {
798                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
799                 .procname       = "lowmem_reserve_ratio",
800                 .data           = &sysctl_lowmem_reserve_ratio,
801                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
802                 .mode           = 0644,
803                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
804                 .strategy       = &sysctl_intvec,
805         },
806         {
807                 .ctl_name       = VM_DROP_PAGECACHE,
808                 .procname       = "drop_caches",
809                 .data           = &sysctl_drop_caches,
810                 .maxlen         = sizeof(int),
811                 .mode           = 0644,
812                 .proc_handler   = drop_caches_sysctl_handler,
813                 .strategy       = &sysctl_intvec,
814         },
815         {
816                 .ctl_name       = VM_MIN_FREE_KBYTES,
817                 .procname       = "min_free_kbytes",
818                 .data           = &min_free_kbytes,
819                 .maxlen         = sizeof(min_free_kbytes),
820                 .mode           = 0644,
821                 .proc_handler   = &min_free_kbytes_sysctl_handler,
822                 .strategy       = &sysctl_intvec,
823                 .extra1         = &zero,
824         },
825         {
826                 .ctl_name       = VM_PERCPU_PAGELIST_FRACTION,
827                 .procname       = "percpu_pagelist_fraction",
828                 .data           = &percpu_pagelist_fraction,
829                 .maxlen         = sizeof(percpu_pagelist_fraction),
830                 .mode           = 0644,
831                 .proc_handler   = &percpu_pagelist_fraction_sysctl_handler,
832                 .strategy       = &sysctl_intvec,
833                 .extra1         = &min_percpu_pagelist_fract,
834         },
835 #ifdef CONFIG_MMU
836         {
837                 .ctl_name       = VM_MAX_MAP_COUNT,
838                 .procname       = "max_map_count",
839                 .data           = &sysctl_max_map_count,
840                 .maxlen         = sizeof(sysctl_max_map_count),
841                 .mode           = 0644,
842                 .proc_handler   = &proc_dointvec
843         },
844 #endif
845         {
846                 .ctl_name       = VM_LAPTOP_MODE,
847                 .procname       = "laptop_mode",
848                 .data           = &laptop_mode,
849                 .maxlen         = sizeof(laptop_mode),
850                 .mode           = 0644,
851                 .proc_handler   = &proc_dointvec_jiffies,
852                 .strategy       = &sysctl_jiffies,
853         },
854         {
855                 .ctl_name       = VM_BLOCK_DUMP,
856                 .procname       = "block_dump",
857                 .data           = &block_dump,
858                 .maxlen         = sizeof(block_dump),
859                 .mode           = 0644,
860                 .proc_handler   = &proc_dointvec,
861                 .strategy       = &sysctl_intvec,
862                 .extra1         = &zero,
863         },
864         {
865                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
866                 .procname       = "vfs_cache_pressure",
867                 .data           = &sysctl_vfs_cache_pressure,
868                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
869                 .mode           = 0644,
870                 .proc_handler   = &proc_dointvec,
871                 .strategy       = &sysctl_intvec,
872                 .extra1         = &zero,
873         },
874 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
875         {
876                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
877                 .procname       = "legacy_va_layout",
878                 .data           = &sysctl_legacy_va_layout,
879                 .maxlen         = sizeof(sysctl_legacy_va_layout),
880                 .mode           = 0644,
881                 .proc_handler   = &proc_dointvec,
882                 .strategy       = &sysctl_intvec,
883                 .extra1         = &zero,
884         },
885 #endif
886 #ifdef CONFIG_SWAP
887         {
888                 .ctl_name       = VM_SWAP_TOKEN_TIMEOUT,
889                 .procname       = "swap_token_timeout",
890                 .data           = &swap_token_default_timeout,
891                 .maxlen         = sizeof(swap_token_default_timeout),
892                 .mode           = 0644,
893                 .proc_handler   = &proc_dointvec_jiffies,
894                 .strategy       = &sysctl_jiffies,
895         },
896 #endif
897 #ifdef CONFIG_NUMA
898         {
899                 .ctl_name       = VM_ZONE_RECLAIM_MODE,
900                 .procname       = "zone_reclaim_mode",
901                 .data           = &zone_reclaim_mode,
902                 .maxlen         = sizeof(zone_reclaim_mode),
903                 .mode           = 0644,
904                 .proc_handler   = &proc_dointvec,
905                 .strategy       = &sysctl_intvec,
906                 .extra1         = &zero,
907         },
908         {
909                 .ctl_name       = VM_ZONE_RECLAIM_INTERVAL,
910                 .procname       = "zone_reclaim_interval",
911                 .data           = &zone_reclaim_interval,
912                 .maxlen         = sizeof(zone_reclaim_interval),
913                 .mode           = 0644,
914                 .proc_handler   = &proc_dointvec_jiffies,
915                 .strategy       = &sysctl_jiffies,
916         },
917 #endif
918         { .ctl_name = 0 }
919 };
920
921 static ctl_table proc_table[] = {
922         { .ctl_name = 0 }
923 };
924
925 static ctl_table fs_table[] = {
926         {
927                 .ctl_name       = FS_NRINODE,
928                 .procname       = "inode-nr",
929                 .data           = &inodes_stat,
930                 .maxlen         = 2*sizeof(int),
931                 .mode           = 0444,
932                 .proc_handler   = &proc_dointvec,
933         },
934         {
935                 .ctl_name       = FS_STATINODE,
936                 .procname       = "inode-state",
937                 .data           = &inodes_stat,
938                 .maxlen         = 7*sizeof(int),
939                 .mode           = 0444,
940                 .proc_handler   = &proc_dointvec,
941         },
942         {
943                 .ctl_name       = FS_NRFILE,
944                 .procname       = "file-nr",
945                 .data           = &files_stat,
946                 .maxlen         = 3*sizeof(int),
947                 .mode           = 0444,
948                 .proc_handler   = &proc_nr_files,
949         },
950         {
951                 .ctl_name       = FS_MAXFILE,
952                 .procname       = "file-max",
953                 .data           = &files_stat.max_files,
954                 .maxlen         = sizeof(int),
955                 .mode           = 0644,
956                 .proc_handler   = &proc_dointvec,
957         },
958         {
959                 .ctl_name       = FS_DENTRY,
960                 .procname       = "dentry-state",
961                 .data           = &dentry_stat,
962                 .maxlen         = 6*sizeof(int),
963                 .mode           = 0444,
964                 .proc_handler   = &proc_dointvec,
965         },
966         {
967                 .ctl_name       = FS_OVERFLOWUID,
968                 .procname       = "overflowuid",
969                 .data           = &fs_overflowuid,
970                 .maxlen         = sizeof(int),
971                 .mode           = 0644,
972                 .proc_handler   = &proc_dointvec_minmax,
973                 .strategy       = &sysctl_intvec,
974                 .extra1         = &minolduid,
975                 .extra2         = &maxolduid,
976         },
977         {
978                 .ctl_name       = FS_OVERFLOWGID,
979                 .procname       = "overflowgid",
980                 .data           = &fs_overflowgid,
981                 .maxlen         = sizeof(int),
982                 .mode           = 0644,
983                 .proc_handler   = &proc_dointvec_minmax,
984                 .strategy       = &sysctl_intvec,
985                 .extra1         = &minolduid,
986                 .extra2         = &maxolduid,
987         },
988         {
989                 .ctl_name       = FS_LEASES,
990                 .procname       = "leases-enable",
991                 .data           = &leases_enable,
992                 .maxlen         = sizeof(int),
993                 .mode           = 0644,
994                 .proc_handler   = &proc_dointvec,
995         },
996 #ifdef CONFIG_DNOTIFY
997         {
998                 .ctl_name       = FS_DIR_NOTIFY,
999                 .procname       = "dir-notify-enable",
1000                 .data           = &dir_notify_enable,
1001                 .maxlen         = sizeof(int),
1002                 .mode           = 0644,
1003                 .proc_handler   = &proc_dointvec,
1004         },
1005 #endif
1006 #ifdef CONFIG_MMU
1007         {
1008                 .ctl_name       = FS_LEASE_TIME,
1009                 .procname       = "lease-break-time",
1010                 .data           = &lease_break_time,
1011                 .maxlen         = sizeof(int),
1012                 .mode           = 0644,
1013                 .proc_handler   = &proc_dointvec,
1014         },
1015         {
1016                 .ctl_name       = FS_AIO_NR,
1017                 .procname       = "aio-nr",
1018                 .data           = &aio_nr,
1019                 .maxlen         = sizeof(aio_nr),
1020                 .mode           = 0444,
1021                 .proc_handler   = &proc_doulongvec_minmax,
1022         },
1023         {
1024                 .ctl_name       = FS_AIO_MAX_NR,
1025                 .procname       = "aio-max-nr",
1026                 .data           = &aio_max_nr,
1027                 .maxlen         = sizeof(aio_max_nr),
1028                 .mode           = 0644,
1029                 .proc_handler   = &proc_doulongvec_minmax,
1030         },
1031 #ifdef CONFIG_INOTIFY_USER
1032         {
1033                 .ctl_name       = FS_INOTIFY,
1034                 .procname       = "inotify",
1035                 .mode           = 0555,
1036                 .child          = inotify_table,
1037         },
1038 #endif  
1039 #endif
1040         {
1041                 .ctl_name       = KERN_SETUID_DUMPABLE,
1042                 .procname       = "suid_dumpable",
1043                 .data           = &suid_dumpable,
1044                 .maxlen         = sizeof(int),
1045                 .mode           = 0644,
1046                 .proc_handler   = &proc_dointvec,
1047         },
1048         { .ctl_name = 0 }
1049 };
1050
1051 static ctl_table debug_table[] = {
1052         { .ctl_name = 0 }
1053 };
1054
1055 static ctl_table dev_table[] = {
1056         { .ctl_name = 0 }
1057 };
1058
1059 extern void init_irq_proc (void);
1060
1061 static DEFINE_SPINLOCK(sysctl_lock);
1062
1063 /* called under sysctl_lock */
1064 static int use_table(struct ctl_table_header *p)
1065 {
1066         if (unlikely(p->unregistering))
1067                 return 0;
1068         p->used++;
1069         return 1;
1070 }
1071
1072 /* called under sysctl_lock */
1073 static void unuse_table(struct ctl_table_header *p)
1074 {
1075         if (!--p->used)
1076                 if (unlikely(p->unregistering))
1077                         complete(p->unregistering);
1078 }
1079
1080 /* called under sysctl_lock, will reacquire if has to wait */
1081 static void start_unregistering(struct ctl_table_header *p)
1082 {
1083         /*
1084          * if p->used is 0, nobody will ever touch that entry again;
1085          * we'll eliminate all paths to it before dropping sysctl_lock
1086          */
1087         if (unlikely(p->used)) {
1088                 struct completion wait;
1089                 init_completion(&wait);
1090                 p->unregistering = &wait;
1091                 spin_unlock(&sysctl_lock);
1092                 wait_for_completion(&wait);
1093                 spin_lock(&sysctl_lock);
1094         }
1095         /*
1096          * do not remove from the list until nobody holds it; walking the
1097          * list in do_sysctl() relies on that.
1098          */
1099         list_del_init(&p->ctl_entry);
1100 }
1101
1102 void __init sysctl_init(void)
1103 {
1104 #ifdef CONFIG_PROC_FS
1105         register_proc_table(root_table, proc_sys_root, &root_table_header);
1106         init_irq_proc();
1107 #endif
1108 }
1109
1110 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1111                void __user *newval, size_t newlen)
1112 {
1113         struct list_head *tmp;
1114         int error = -ENOTDIR;
1115
1116         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1117                 return -ENOTDIR;
1118         if (oldval) {
1119                 int old_len;
1120                 if (!oldlenp || get_user(old_len, oldlenp))
1121                         return -EFAULT;
1122         }
1123         spin_lock(&sysctl_lock);
1124         tmp = &root_table_header.ctl_entry;
1125         do {
1126                 struct ctl_table_header *head =
1127                         list_entry(tmp, struct ctl_table_header, ctl_entry);
1128                 void *context = NULL;
1129
1130                 if (!use_table(head))
1131                         continue;
1132
1133                 spin_unlock(&sysctl_lock);
1134
1135                 error = parse_table(name, nlen, oldval, oldlenp, 
1136                                         newval, newlen, head->ctl_table,
1137                                         &context);
1138                 kfree(context);
1139
1140                 spin_lock(&sysctl_lock);
1141                 unuse_table(head);
1142                 if (error != -ENOTDIR)
1143                         break;
1144         } while ((tmp = tmp->next) != &root_table_header.ctl_entry);
1145         spin_unlock(&sysctl_lock);
1146         return error;
1147 }
1148
1149 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1150 {
1151         struct __sysctl_args tmp;
1152         int error;
1153
1154         if (copy_from_user(&tmp, args, sizeof(tmp)))
1155                 return -EFAULT;
1156
1157         lock_kernel();
1158         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1159                           tmp.newval, tmp.newlen);
1160         unlock_kernel();
1161         return error;
1162 }
1163
1164 /*
1165  * ctl_perm does NOT grant the superuser all rights automatically, because
1166  * some sysctl variables are readonly even to root.
1167  */
1168
1169 static int test_perm(int mode, int op)
1170 {
1171         if (!current->euid)
1172                 mode >>= 6;
1173         else if (in_egroup_p(0))
1174                 mode >>= 3;
1175         if ((mode & op & 0007) == op)
1176                 return 0;
1177         return -EACCES;
1178 }
1179
1180 static inline int ctl_perm(ctl_table *table, int op)
1181 {
1182         int error;
1183         error = security_sysctl(table, op);
1184         if (error)
1185                 return error;
1186         return test_perm(table->mode, op);
1187 }
1188
1189 static int parse_table(int __user *name, int nlen,
1190                        void __user *oldval, size_t __user *oldlenp,
1191                        void __user *newval, size_t newlen,
1192                        ctl_table *table, void **context)
1193 {
1194         int n;
1195 repeat:
1196         if (!nlen)
1197                 return -ENOTDIR;
1198         if (get_user(n, name))
1199                 return -EFAULT;
1200         for ( ; table->ctl_name; table++) {
1201                 if (n == table->ctl_name || table->ctl_name == CTL_ANY) {
1202                         int error;
1203                         if (table->child) {
1204                                 if (ctl_perm(table, 001))
1205                                         return -EPERM;
1206                                 if (table->strategy) {
1207                                         error = table->strategy(
1208                                                 table, name, nlen,
1209                                                 oldval, oldlenp,
1210                                                 newval, newlen, context);
1211                                         if (error)
1212                                                 return error;
1213                                 }
1214                                 name++;
1215                                 nlen--;
1216                                 table = table->child;
1217                                 goto repeat;
1218                         }
1219                         error = do_sysctl_strategy(table, name, nlen,
1220                                                    oldval, oldlenp,
1221                                                    newval, newlen, context);
1222                         return error;
1223                 }
1224         }
1225         return -ENOTDIR;
1226 }
1227
1228 /* Perform the actual read/write of a sysctl table entry. */
1229 int do_sysctl_strategy (ctl_table *table, 
1230                         int __user *name, int nlen,
1231                         void __user *oldval, size_t __user *oldlenp,
1232                         void __user *newval, size_t newlen, void **context)
1233 {
1234         int op = 0, rc;
1235         size_t len;
1236
1237         if (oldval)
1238                 op |= 004;
1239         if (newval) 
1240                 op |= 002;
1241         if (ctl_perm(table, op))
1242                 return -EPERM;
1243
1244         if (table->strategy) {
1245                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1246                                      newval, newlen, context);
1247                 if (rc < 0)
1248                         return rc;
1249                 if (rc > 0)
1250                         return 0;
1251         }
1252
1253         /* If there is no strategy routine, or if the strategy returns
1254          * zero, proceed with automatic r/w */
1255         if (table->data && table->maxlen) {
1256                 if (oldval && oldlenp) {
1257                         if (get_user(len, oldlenp))
1258                                 return -EFAULT;
1259                         if (len) {
1260                                 if (len > table->maxlen)
1261                                         len = table->maxlen;
1262                                 if(copy_to_user(oldval, table->data, len))
1263                                         return -EFAULT;
1264                                 if(put_user(len, oldlenp))
1265                                         return -EFAULT;
1266                         }
1267                 }
1268                 if (newval && newlen) {
1269                         len = newlen;
1270                         if (len > table->maxlen)
1271                                 len = table->maxlen;
1272                         if(copy_from_user(table->data, newval, len))
1273                                 return -EFAULT;
1274                 }
1275         }
1276         return 0;
1277 }
1278
1279 /**
1280  * register_sysctl_table - register a sysctl hierarchy
1281  * @table: the top-level table structure
1282  * @insert_at_head: whether the entry should be inserted in front or at the end
1283  *
1284  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1285  * array. An entry with a ctl_name of 0 terminates the table. 
1286  *
1287  * The members of the &ctl_table structure are used as follows:
1288  *
1289  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1290  *            must be unique within that level of sysctl
1291  *
1292  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1293  *            enter a sysctl file
1294  *
1295  * data - a pointer to data for use by proc_handler
1296  *
1297  * maxlen - the maximum size in bytes of the data
1298  *
1299  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1300  *
1301  * child - a pointer to the child sysctl table if this entry is a directory, or
1302  *         %NULL.
1303  *
1304  * proc_handler - the text handler routine (described below)
1305  *
1306  * strategy - the strategy routine (described below)
1307  *
1308  * de - for internal use by the sysctl routines
1309  *
1310  * extra1, extra2 - extra pointers usable by the proc handler routines
1311  *
1312  * Leaf nodes in the sysctl tree will be represented by a single file
1313  * under /proc; non-leaf nodes will be represented by directories.
1314  *
1315  * sysctl(2) can automatically manage read and write requests through
1316  * the sysctl table.  The data and maxlen fields of the ctl_table
1317  * struct enable minimal validation of the values being written to be
1318  * performed, and the mode field allows minimal authentication.
1319  *
1320  * More sophisticated management can be enabled by the provision of a
1321  * strategy routine with the table entry.  This will be called before
1322  * any automatic read or write of the data is performed.
1323  *
1324  * The strategy routine may return
1325  *
1326  * < 0 - Error occurred (error is passed to user process)
1327  *
1328  * 0   - OK - proceed with automatic read or write.
1329  *
1330  * > 0 - OK - read or write has been done by the strategy routine, so
1331  *       return immediately.
1332  *
1333  * There must be a proc_handler routine for any terminal nodes
1334  * mirrored under /proc/sys (non-terminals are handled by a built-in
1335  * directory handler).  Several default handlers are available to
1336  * cover common cases -
1337  *
1338  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1339  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(), 
1340  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1341  *
1342  * It is the handler's job to read the input buffer from user memory
1343  * and process it. The handler should return 0 on success.
1344  *
1345  * This routine returns %NULL on a failure to register, and a pointer
1346  * to the table header on success.
1347  */
1348 struct ctl_table_header *register_sysctl_table(ctl_table * table, 
1349                                                int insert_at_head)
1350 {
1351         struct ctl_table_header *tmp;
1352         tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1353         if (!tmp)
1354                 return NULL;
1355         tmp->ctl_table = table;
1356         INIT_LIST_HEAD(&tmp->ctl_entry);
1357         tmp->used = 0;
1358         tmp->unregistering = NULL;
1359         spin_lock(&sysctl_lock);
1360         if (insert_at_head)
1361                 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
1362         else
1363                 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1364         spin_unlock(&sysctl_lock);
1365 #ifdef CONFIG_PROC_FS
1366         register_proc_table(table, proc_sys_root, tmp);
1367 #endif
1368         return tmp;
1369 }
1370
1371 /**
1372  * unregister_sysctl_table - unregister a sysctl table hierarchy
1373  * @header: the header returned from register_sysctl_table
1374  *
1375  * Unregisters the sysctl table and all children. proc entries may not
1376  * actually be removed until they are no longer used by anyone.
1377  */
1378 void unregister_sysctl_table(struct ctl_table_header * header)
1379 {
1380         might_sleep();
1381         spin_lock(&sysctl_lock);
1382         start_unregistering(header);
1383 #ifdef CONFIG_PROC_FS
1384         unregister_proc_table(header->ctl_table, proc_sys_root);
1385 #endif
1386         spin_unlock(&sysctl_lock);
1387         kfree(header);
1388 }
1389
1390 /*
1391  * /proc/sys support
1392  */
1393
1394 #ifdef CONFIG_PROC_FS
1395
1396 /* Scan the sysctl entries in table and add them all into /proc */
1397 static void register_proc_table(ctl_table * table, struct proc_dir_entry *root, void *set)
1398 {
1399         struct proc_dir_entry *de;
1400         int len;
1401         mode_t mode;
1402         
1403         for (; table->ctl_name; table++) {
1404                 /* Can't do anything without a proc name. */
1405                 if (!table->procname)
1406                         continue;
1407                 /* Maybe we can't do anything with it... */
1408                 if (!table->proc_handler && !table->child) {
1409                         printk(KERN_WARNING "SYSCTL: Can't register %s\n",
1410                                 table->procname);
1411                         continue;
1412                 }
1413
1414                 len = strlen(table->procname);
1415                 mode = table->mode;
1416
1417                 de = NULL;
1418                 if (table->proc_handler)
1419                         mode |= S_IFREG;
1420                 else {
1421                         mode |= S_IFDIR;
1422                         for (de = root->subdir; de; de = de->next) {
1423                                 if (proc_match(len, table->procname, de))
1424                                         break;
1425                         }
1426                         /* If the subdir exists already, de is non-NULL */
1427                 }
1428
1429                 if (!de) {
1430                         de = create_proc_entry(table->procname, mode, root);
1431                         if (!de)
1432                                 continue;
1433                         de->set = set;
1434                         de->data = (void *) table;
1435                         if (table->proc_handler)
1436                                 de->proc_fops = &proc_sys_file_operations;
1437                 }
1438                 table->de = de;
1439                 if (de->mode & S_IFDIR)
1440                         register_proc_table(table->child, de, set);
1441         }
1442 }
1443
1444 /*
1445  * Unregister a /proc sysctl table and any subdirectories.
1446  */
1447 static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
1448 {
1449         struct proc_dir_entry *de;
1450         for (; table->ctl_name; table++) {
1451                 if (!(de = table->de))
1452                         continue;
1453                 if (de->mode & S_IFDIR) {
1454                         if (!table->child) {
1455                                 printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
1456                                 continue;
1457                         }
1458                         unregister_proc_table(table->child, de);
1459
1460                         /* Don't unregister directories which still have entries.. */
1461                         if (de->subdir)
1462                                 continue;
1463                 }
1464
1465                 /*
1466                  * In any case, mark the entry as goner; we'll keep it
1467                  * around if it's busy, but we'll know to do nothing with
1468                  * its fields.  We are under sysctl_lock here.
1469                  */
1470                 de->data = NULL;
1471
1472                 /* Don't unregister proc entries that are still being used.. */
1473                 if (atomic_read(&de->count))
1474                         continue;
1475
1476                 table->de = NULL;
1477                 remove_proc_entry(table->procname, root);
1478         }
1479 }
1480
1481 static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
1482                           size_t count, loff_t *ppos)
1483 {
1484         int op;
1485         struct proc_dir_entry *de = PDE(file->f_dentry->d_inode);
1486         struct ctl_table *table;
1487         size_t res;
1488         ssize_t error = -ENOTDIR;
1489         
1490         spin_lock(&sysctl_lock);
1491         if (de && de->data && use_table(de->set)) {
1492                 /*
1493                  * at that point we know that sysctl was not unregistered
1494                  * and won't be until we finish
1495                  */
1496                 spin_unlock(&sysctl_lock);
1497                 table = (struct ctl_table *) de->data;
1498                 if (!table || !table->proc_handler)
1499                         goto out;
1500                 error = -EPERM;
1501                 op = (write ? 002 : 004);
1502                 if (ctl_perm(table, op))
1503                         goto out;
1504                 
1505                 /* careful: calling conventions are nasty here */
1506                 res = count;
1507                 error = (*table->proc_handler)(table, write, file,
1508                                                 buf, &res, ppos);
1509                 if (!error)
1510                         error = res;
1511         out:
1512                 spin_lock(&sysctl_lock);
1513                 unuse_table(de->set);
1514         }
1515         spin_unlock(&sysctl_lock);
1516         return error;
1517 }
1518
1519 static int proc_opensys(struct inode *inode, struct file *file)
1520 {
1521         if (file->f_mode & FMODE_WRITE) {
1522                 /*
1523                  * sysctl entries that are not writable,
1524                  * are _NOT_ writable, capabilities or not.
1525                  */
1526                 if (!(inode->i_mode & S_IWUSR))
1527                         return -EPERM;
1528         }
1529
1530         return 0;
1531 }
1532
1533 static ssize_t proc_readsys(struct file * file, char __user * buf,
1534                             size_t count, loff_t *ppos)
1535 {
1536         return do_rw_proc(0, file, buf, count, ppos);
1537 }
1538
1539 static ssize_t proc_writesys(struct file * file, const char __user * buf,
1540                              size_t count, loff_t *ppos)
1541 {
1542         return do_rw_proc(1, file, (char __user *) buf, count, ppos);
1543 }
1544
1545 /**
1546  * proc_dostring - read a string sysctl
1547  * @table: the sysctl table
1548  * @write: %TRUE if this is a write to the sysctl file
1549  * @filp: the file structure
1550  * @buffer: the user buffer
1551  * @lenp: the size of the user buffer
1552  * @ppos: file position
1553  *
1554  * Reads/writes a string from/to the user buffer. If the kernel
1555  * buffer provided is not large enough to hold the string, the
1556  * string is truncated. The copied string is %NULL-terminated.
1557  * If the string is being read by the user process, it is copied
1558  * and a newline '\n' is added. It is truncated if the buffer is
1559  * not large enough.
1560  *
1561  * Returns 0 on success.
1562  */
1563 int proc_dostring(ctl_table *table, int write, struct file *filp,
1564                   void __user *buffer, size_t *lenp, loff_t *ppos)
1565 {
1566         size_t len;
1567         char __user *p;
1568         char c;
1569         
1570         if (!table->data || !table->maxlen || !*lenp ||
1571             (*ppos && !write)) {
1572                 *lenp = 0;
1573                 return 0;
1574         }
1575         
1576         if (write) {
1577                 len = 0;
1578                 p = buffer;
1579                 while (len < *lenp) {
1580                         if (get_user(c, p++))
1581                                 return -EFAULT;
1582                         if (c == 0 || c == '\n')
1583                                 break;
1584                         len++;
1585                 }
1586                 if (len >= table->maxlen)
1587                         len = table->maxlen-1;
1588                 if(copy_from_user(table->data, buffer, len))
1589                         return -EFAULT;
1590                 ((char *) table->data)[len] = 0;
1591                 *ppos += *lenp;
1592         } else {
1593                 len = strlen(table->data);
1594                 if (len > table->maxlen)
1595                         len = table->maxlen;
1596                 if (len > *lenp)
1597                         len = *lenp;
1598                 if (len)
1599                         if(copy_to_user(buffer, table->data, len))
1600                                 return -EFAULT;
1601                 if (len < *lenp) {
1602                         if(put_user('\n', ((char __user *) buffer) + len))
1603                                 return -EFAULT;
1604                         len++;
1605                 }
1606                 *lenp = len;
1607                 *ppos += len;
1608         }
1609         return 0;
1610 }
1611
1612 /*
1613  *      Special case of dostring for the UTS structure. This has locks
1614  *      to observe. Should this be in kernel/sys.c ????
1615  */
1616  
1617 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
1618                   void __user *buffer, size_t *lenp, loff_t *ppos)
1619 {
1620         int r;
1621
1622         if (!write) {
1623                 down_read(&uts_sem);
1624                 r=proc_dostring(table,0,filp,buffer,lenp, ppos);
1625                 up_read(&uts_sem);
1626         } else {
1627                 down_write(&uts_sem);
1628                 r=proc_dostring(table,1,filp,buffer,lenp, ppos);
1629                 up_write(&uts_sem);
1630         }
1631         return r;
1632 }
1633
1634 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1635                                  int *valp,
1636                                  int write, void *data)
1637 {
1638         if (write) {
1639                 *valp = *negp ? -*lvalp : *lvalp;
1640         } else {
1641                 int val = *valp;
1642                 if (val < 0) {
1643                         *negp = -1;
1644                         *lvalp = (unsigned long)-val;
1645                 } else {
1646                         *negp = 0;
1647                         *lvalp = (unsigned long)val;
1648                 }
1649         }
1650         return 0;
1651 }
1652
1653 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1654                   void __user *buffer, size_t *lenp, loff_t *ppos,
1655                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1656                               int write, void *data),
1657                   void *data)
1658 {
1659 #define TMPBUFLEN 21
1660         int *i, vleft, first=1, neg, val;
1661         unsigned long lval;
1662         size_t left, len;
1663         
1664         char buf[TMPBUFLEN], *p;
1665         char __user *s = buffer;
1666         
1667         if (!table->data || !table->maxlen || !*lenp ||
1668             (*ppos && !write)) {
1669                 *lenp = 0;
1670                 return 0;
1671         }
1672         
1673         i = (int *) table->data;
1674         vleft = table->maxlen / sizeof(*i);
1675         left = *lenp;
1676
1677         if (!conv)
1678                 conv = do_proc_dointvec_conv;
1679
1680         for (; left && vleft--; i++, first=0) {
1681                 if (write) {
1682                         while (left) {
1683                                 char c;
1684                                 if (get_user(c, s))
1685                                         return -EFAULT;
1686                                 if (!isspace(c))
1687                                         break;
1688                                 left--;
1689                                 s++;
1690                         }
1691                         if (!left)
1692                                 break;
1693                         neg = 0;
1694                         len = left;
1695                         if (len > sizeof(buf) - 1)
1696                                 len = sizeof(buf) - 1;
1697                         if (copy_from_user(buf, s, len))
1698                                 return -EFAULT;
1699                         buf[len] = 0;
1700                         p = buf;
1701                         if (*p == '-' && left > 1) {
1702                                 neg = 1;
1703                                 left--, p++;
1704                         }
1705                         if (*p < '0' || *p > '9')
1706                                 break;
1707
1708                         lval = simple_strtoul(p, &p, 0);
1709
1710                         len = p-buf;
1711                         if ((len < left) && *p && !isspace(*p))
1712                                 break;
1713                         if (neg)
1714                                 val = -val;
1715                         s += len;
1716                         left -= len;
1717
1718                         if (conv(&neg, &lval, i, 1, data))
1719                                 break;
1720                 } else {
1721                         p = buf;
1722                         if (!first)
1723                                 *p++ = '\t';
1724         
1725                         if (conv(&neg, &lval, i, 0, data))
1726                                 break;
1727
1728                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
1729                         len = strlen(buf);
1730                         if (len > left)
1731                                 len = left;
1732                         if(copy_to_user(s, buf, len))
1733                                 return -EFAULT;
1734                         left -= len;
1735                         s += len;
1736                 }
1737         }
1738
1739         if (!write && !first && left) {
1740                 if(put_user('\n', s))
1741                         return -EFAULT;
1742                 left--, s++;
1743         }
1744         if (write) {
1745                 while (left) {
1746                         char c;
1747                         if (get_user(c, s++))
1748                                 return -EFAULT;
1749                         if (!isspace(c))
1750                                 break;
1751                         left--;
1752                 }
1753         }
1754         if (write && first)
1755                 return -EINVAL;
1756         *lenp -= left;
1757         *ppos += *lenp;
1758         return 0;
1759 #undef TMPBUFLEN
1760 }
1761
1762 /**
1763  * proc_dointvec - read a vector of integers
1764  * @table: the sysctl table
1765  * @write: %TRUE if this is a write to the sysctl file
1766  * @filp: the file structure
1767  * @buffer: the user buffer
1768  * @lenp: the size of the user buffer
1769  * @ppos: file position
1770  *
1771  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1772  * values from/to the user buffer, treated as an ASCII string. 
1773  *
1774  * Returns 0 on success.
1775  */
1776 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1777                      void __user *buffer, size_t *lenp, loff_t *ppos)
1778 {
1779     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1780                             NULL,NULL);
1781 }
1782
1783 #define OP_SET  0
1784 #define OP_AND  1
1785 #define OP_OR   2
1786 #define OP_MAX  3
1787 #define OP_MIN  4
1788
1789 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1790                                       int *valp,
1791                                       int write, void *data)
1792 {
1793         int op = *(int *)data;
1794         if (write) {
1795                 int val = *negp ? -*lvalp : *lvalp;
1796                 switch(op) {
1797                 case OP_SET:    *valp = val; break;
1798                 case OP_AND:    *valp &= val; break;
1799                 case OP_OR:     *valp |= val; break;
1800                 case OP_MAX:    if(*valp < val)
1801                                         *valp = val;
1802                                 break;
1803                 case OP_MIN:    if(*valp > val)
1804                                 *valp = val;
1805                                 break;
1806                 }
1807         } else {
1808                 int val = *valp;
1809                 if (val < 0) {
1810                         *negp = -1;
1811                         *lvalp = (unsigned long)-val;
1812                 } else {
1813                         *negp = 0;
1814                         *lvalp = (unsigned long)val;
1815                 }
1816         }
1817         return 0;
1818 }
1819
1820 /*
1821  *      init may raise the set.
1822  */
1823  
1824 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1825                         void __user *buffer, size_t *lenp, loff_t *ppos)
1826 {
1827         int op;
1828
1829         if (!capable(CAP_SYS_MODULE)) {
1830                 return -EPERM;
1831         }
1832
1833         op = (current->pid == 1) ? OP_SET : OP_AND;
1834         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1835                                 do_proc_dointvec_bset_conv,&op);
1836 }
1837
1838 struct do_proc_dointvec_minmax_conv_param {
1839         int *min;
1840         int *max;
1841 };
1842
1843 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp, 
1844                                         int *valp, 
1845                                         int write, void *data)
1846 {
1847         struct do_proc_dointvec_minmax_conv_param *param = data;
1848         if (write) {
1849                 int val = *negp ? -*lvalp : *lvalp;
1850                 if ((param->min && *param->min > val) ||
1851                     (param->max && *param->max < val))
1852                         return -EINVAL;
1853                 *valp = val;
1854         } else {
1855                 int val = *valp;
1856                 if (val < 0) {
1857                         *negp = -1;
1858                         *lvalp = (unsigned long)-val;
1859                 } else {
1860                         *negp = 0;
1861                         *lvalp = (unsigned long)val;
1862                 }
1863         }
1864         return 0;
1865 }
1866
1867 /**
1868  * proc_dointvec_minmax - read a vector of integers with min/max values
1869  * @table: the sysctl table
1870  * @write: %TRUE if this is a write to the sysctl file
1871  * @filp: the file structure
1872  * @buffer: the user buffer
1873  * @lenp: the size of the user buffer
1874  * @ppos: file position
1875  *
1876  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1877  * values from/to the user buffer, treated as an ASCII string.
1878  *
1879  * This routine will ensure the values are within the range specified by
1880  * table->extra1 (min) and table->extra2 (max).
1881  *
1882  * Returns 0 on success.
1883  */
1884 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1885                   void __user *buffer, size_t *lenp, loff_t *ppos)
1886 {
1887         struct do_proc_dointvec_minmax_conv_param param = {
1888                 .min = (int *) table->extra1,
1889                 .max = (int *) table->extra2,
1890         };
1891         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1892                                 do_proc_dointvec_minmax_conv, &param);
1893 }
1894
1895 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1896                                      struct file *filp,
1897                                      void __user *buffer,
1898                                      size_t *lenp, loff_t *ppos,
1899                                      unsigned long convmul,
1900                                      unsigned long convdiv)
1901 {
1902 #define TMPBUFLEN 21
1903         unsigned long *i, *min, *max, val;
1904         int vleft, first=1, neg;
1905         size_t len, left;
1906         char buf[TMPBUFLEN], *p;
1907         char __user *s = buffer;
1908         
1909         if (!table->data || !table->maxlen || !*lenp ||
1910             (*ppos && !write)) {
1911                 *lenp = 0;
1912                 return 0;
1913         }
1914         
1915         i = (unsigned long *) table->data;
1916         min = (unsigned long *) table->extra1;
1917         max = (unsigned long *) table->extra2;
1918         vleft = table->maxlen / sizeof(unsigned long);
1919         left = *lenp;
1920         
1921         for (; left && vleft--; i++, min++, max++, first=0) {
1922                 if (write) {
1923                         while (left) {
1924                                 char c;
1925                                 if (get_user(c, s))
1926                                         return -EFAULT;
1927                                 if (!isspace(c))
1928                                         break;
1929                                 left--;
1930                                 s++;
1931                         }
1932                         if (!left)
1933                                 break;
1934                         neg = 0;
1935                         len = left;
1936                         if (len > TMPBUFLEN-1)
1937                                 len = TMPBUFLEN-1;
1938                         if (copy_from_user(buf, s, len))
1939                                 return -EFAULT;
1940                         buf[len] = 0;
1941                         p = buf;
1942                         if (*p == '-' && left > 1) {
1943                                 neg = 1;
1944                                 left--, p++;
1945                         }
1946                         if (*p < '0' || *p > '9')
1947                                 break;
1948                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1949                         len = p-buf;
1950                         if ((len < left) && *p && !isspace(*p))
1951                                 break;
1952                         if (neg)
1953                                 val = -val;
1954                         s += len;
1955                         left -= len;
1956
1957                         if(neg)
1958                                 continue;
1959                         if ((min && val < *min) || (max && val > *max))
1960                                 continue;
1961                         *i = val;
1962                 } else {
1963                         p = buf;
1964                         if (!first)
1965                                 *p++ = '\t';
1966                         sprintf(p, "%lu", convdiv * (*i) / convmul);
1967                         len = strlen(buf);
1968                         if (len > left)
1969                                 len = left;
1970                         if(copy_to_user(s, buf, len))
1971                                 return -EFAULT;
1972                         left -= len;
1973                         s += len;
1974                 }
1975         }
1976
1977         if (!write && !first && left) {
1978                 if(put_user('\n', s))
1979                         return -EFAULT;
1980                 left--, s++;
1981         }
1982         if (write) {
1983                 while (left) {
1984                         char c;
1985                         if (get_user(c, s++))
1986                                 return -EFAULT;
1987                         if (!isspace(c))
1988                                 break;
1989                         left--;
1990                 }
1991         }
1992         if (write && first)
1993                 return -EINVAL;
1994         *lenp -= left;
1995         *ppos += *lenp;
1996         return 0;
1997 #undef TMPBUFLEN
1998 }
1999
2000 /**
2001  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2002  * @table: the sysctl table
2003  * @write: %TRUE if this is a write to the sysctl file
2004  * @filp: the file structure
2005  * @buffer: the user buffer
2006  * @lenp: the size of the user buffer
2007  * @ppos: file position
2008  *
2009  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2010  * values from/to the user buffer, treated as an ASCII string.
2011  *
2012  * This routine will ensure the values are within the range specified by
2013  * table->extra1 (min) and table->extra2 (max).
2014  *
2015  * Returns 0 on success.
2016  */
2017 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2018                            void __user *buffer, size_t *lenp, loff_t *ppos)
2019 {
2020     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2021 }
2022
2023 /**
2024  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2025  * @table: the sysctl table
2026  * @write: %TRUE if this is a write to the sysctl file
2027  * @filp: the file structure
2028  * @buffer: the user buffer
2029  * @lenp: the size of the user buffer
2030  * @ppos: file position
2031  *
2032  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2033  * values from/to the user buffer, treated as an ASCII string. The values
2034  * are treated as milliseconds, and converted to jiffies when they are stored.
2035  *
2036  * This routine will ensure the values are within the range specified by
2037  * table->extra1 (min) and table->extra2 (max).
2038  *
2039  * Returns 0 on success.
2040  */
2041 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2042                                       struct file *filp,
2043                                       void __user *buffer,
2044                                       size_t *lenp, loff_t *ppos)
2045 {
2046     return do_proc_doulongvec_minmax(table, write, filp, buffer,
2047                                      lenp, ppos, HZ, 1000l);
2048 }
2049
2050
2051 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2052                                          int *valp,
2053                                          int write, void *data)
2054 {
2055         if (write) {
2056                 if (*lvalp > LONG_MAX / HZ)
2057                         return 1;
2058                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2059         } else {
2060                 int val = *valp;
2061                 unsigned long lval;
2062                 if (val < 0) {
2063                         *negp = -1;
2064                         lval = (unsigned long)-val;
2065                 } else {
2066                         *negp = 0;
2067                         lval = (unsigned long)val;
2068                 }
2069                 *lvalp = lval / HZ;
2070         }
2071         return 0;
2072 }
2073
2074 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2075                                                 int *valp,
2076                                                 int write, void *data)
2077 {
2078         if (write) {
2079                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2080                         return 1;
2081                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2082         } else {
2083                 int val = *valp;
2084                 unsigned long lval;
2085                 if (val < 0) {
2086                         *negp = -1;
2087                         lval = (unsigned long)-val;
2088                 } else {
2089                         *negp = 0;
2090                         lval = (unsigned long)val;
2091                 }
2092                 *lvalp = jiffies_to_clock_t(lval);
2093         }
2094         return 0;
2095 }
2096
2097 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2098                                             int *valp,
2099                                             int write, void *data)
2100 {
2101         if (write) {
2102                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2103         } else {
2104                 int val = *valp;
2105                 unsigned long lval;
2106                 if (val < 0) {
2107                         *negp = -1;
2108                         lval = (unsigned long)-val;
2109                 } else {
2110                         *negp = 0;
2111                         lval = (unsigned long)val;
2112                 }
2113                 *lvalp = jiffies_to_msecs(lval);
2114         }
2115         return 0;
2116 }
2117
2118 /**
2119  * proc_dointvec_jiffies - read a vector of integers as seconds
2120  * @table: the sysctl table
2121  * @write: %TRUE if this is a write to the sysctl file
2122  * @filp: the file structure
2123  * @buffer: the user buffer
2124  * @lenp: the size of the user buffer
2125  * @ppos: file position
2126  *
2127  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2128  * values from/to the user buffer, treated as an ASCII string. 
2129  * The values read are assumed to be in seconds, and are converted into
2130  * jiffies.
2131  *
2132  * Returns 0 on success.
2133  */
2134 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2135                           void __user *buffer, size_t *lenp, loff_t *ppos)
2136 {
2137     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2138                             do_proc_dointvec_jiffies_conv,NULL);
2139 }
2140
2141 /**
2142  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2143  * @table: the sysctl table
2144  * @write: %TRUE if this is a write to the sysctl file
2145  * @filp: the file structure
2146  * @buffer: the user buffer
2147  * @lenp: the size of the user buffer
2148  * @ppos: pointer to the file position
2149  *
2150  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2151  * values from/to the user buffer, treated as an ASCII string. 
2152  * The values read are assumed to be in 1/USER_HZ seconds, and 
2153  * are converted into jiffies.
2154  *
2155  * Returns 0 on success.
2156  */
2157 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2158                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2159 {
2160     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2161                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2162 }
2163
2164 /**
2165  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2166  * @table: the sysctl table
2167  * @write: %TRUE if this is a write to the sysctl file
2168  * @filp: the file structure
2169  * @buffer: the user buffer
2170  * @lenp: the size of the user buffer
2171  * @ppos: file position
2172  * @ppos: the current position in the file
2173  *
2174  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2175  * values from/to the user buffer, treated as an ASCII string. 
2176  * The values read are assumed to be in 1/1000 seconds, and 
2177  * are converted into jiffies.
2178  *
2179  * Returns 0 on success.
2180  */
2181 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2182                              void __user *buffer, size_t *lenp, loff_t *ppos)
2183 {
2184         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2185                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2186 }
2187
2188 #else /* CONFIG_PROC_FS */
2189
2190 int proc_dostring(ctl_table *table, int write, struct file *filp,
2191                   void __user *buffer, size_t *lenp, loff_t *ppos)
2192 {
2193         return -ENOSYS;
2194 }
2195
2196 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
2197                             void __user *buffer, size_t *lenp, loff_t *ppos)
2198 {
2199         return -ENOSYS;
2200 }
2201
2202 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2203                   void __user *buffer, size_t *lenp, loff_t *ppos)
2204 {
2205         return -ENOSYS;
2206 }
2207
2208 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2209                         void __user *buffer, size_t *lenp, loff_t *ppos)
2210 {
2211         return -ENOSYS;
2212 }
2213
2214 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2215                     void __user *buffer, size_t *lenp, loff_t *ppos)
2216 {
2217         return -ENOSYS;
2218 }
2219
2220 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2221                     void __user *buffer, size_t *lenp, loff_t *ppos)
2222 {
2223         return -ENOSYS;
2224 }
2225
2226 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2227                     void __user *buffer, size_t *lenp, loff_t *ppos)
2228 {
2229         return -ENOSYS;
2230 }
2231
2232 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2233                              void __user *buffer, size_t *lenp, loff_t *ppos)
2234 {
2235         return -ENOSYS;
2236 }
2237
2238 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2239                     void __user *buffer, size_t *lenp, loff_t *ppos)
2240 {
2241         return -ENOSYS;
2242 }
2243
2244 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2245                                       struct file *filp,
2246                                       void __user *buffer,
2247                                       size_t *lenp, loff_t *ppos)
2248 {
2249     return -ENOSYS;
2250 }
2251
2252
2253 #endif /* CONFIG_PROC_FS */
2254
2255
2256 /*
2257  * General sysctl support routines 
2258  */
2259
2260 /* The generic string strategy routine: */
2261 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2262                   void __user *oldval, size_t __user *oldlenp,
2263                   void __user *newval, size_t newlen, void **context)
2264 {
2265         if (!table->data || !table->maxlen) 
2266                 return -ENOTDIR;
2267         
2268         if (oldval && oldlenp) {
2269                 size_t bufsize;
2270                 if (get_user(bufsize, oldlenp))
2271                         return -EFAULT;
2272                 if (bufsize) {
2273                         size_t len = strlen(table->data), copied;
2274
2275                         /* This shouldn't trigger for a well-formed sysctl */
2276                         if (len > table->maxlen)
2277                                 len = table->maxlen;
2278
2279                         /* Copy up to a max of bufsize-1 bytes of the string */
2280                         copied = (len >= bufsize) ? bufsize - 1 : len;
2281
2282                         if (copy_to_user(oldval, table->data, copied) ||
2283                             put_user(0, (char __user *)(oldval + copied)))
2284                                 return -EFAULT;
2285                         if (put_user(len, oldlenp))
2286                                 return -EFAULT;
2287                 }
2288         }
2289         if (newval && newlen) {
2290                 size_t len = newlen;
2291                 if (len > table->maxlen)
2292                         len = table->maxlen;
2293                 if(copy_from_user(table->data, newval, len))
2294                         return -EFAULT;
2295                 if (len == table->maxlen)
2296                         len--;
2297                 ((char *) table->data)[len] = 0;
2298         }
2299         return 1;
2300 }
2301
2302 /*
2303  * This function makes sure that all of the integers in the vector
2304  * are between the minimum and maximum values given in the arrays
2305  * table->extra1 and table->extra2, respectively.
2306  */
2307 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2308                 void __user *oldval, size_t __user *oldlenp,
2309                 void __user *newval, size_t newlen, void **context)
2310 {
2311
2312         if (newval && newlen) {
2313                 int __user *vec = (int __user *) newval;
2314                 int *min = (int *) table->extra1;
2315                 int *max = (int *) table->extra2;
2316                 size_t length;
2317                 int i;
2318
2319                 if (newlen % sizeof(int) != 0)
2320                         return -EINVAL;
2321
2322                 if (!table->extra1 && !table->extra2)
2323                         return 0;
2324
2325                 if (newlen > table->maxlen)
2326                         newlen = table->maxlen;
2327                 length = newlen / sizeof(int);
2328
2329                 for (i = 0; i < length; i++) {
2330                         int value;
2331                         if (get_user(value, vec + i))
2332                                 return -EFAULT;
2333                         if (min && value < min[i])
2334                                 return -EINVAL;
2335                         if (max && value > max[i])
2336                                 return -EINVAL;
2337                 }
2338         }
2339         return 0;
2340 }
2341
2342 /* Strategy function to convert jiffies to seconds */ 
2343 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2344                 void __user *oldval, size_t __user *oldlenp,
2345                 void __user *newval, size_t newlen, void **context)
2346 {
2347         if (oldval) {
2348                 size_t olen;
2349                 if (oldlenp) { 
2350                         if (get_user(olen, oldlenp))
2351                                 return -EFAULT;
2352                         if (olen!=sizeof(int))
2353                                 return -EINVAL; 
2354                 }
2355                 if (put_user(*(int *)(table->data)/HZ, (int __user *)oldval) ||
2356                     (oldlenp && put_user(sizeof(int),oldlenp)))
2357                         return -EFAULT;
2358         }
2359         if (newval && newlen) { 
2360                 int new;
2361                 if (newlen != sizeof(int))
2362                         return -EINVAL; 
2363                 if (get_user(new, (int __user *)newval))
2364                         return -EFAULT;
2365                 *(int *)(table->data) = new*HZ; 
2366         }
2367         return 1;
2368 }
2369
2370 /* Strategy function to convert jiffies to seconds */ 
2371 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2372                 void __user *oldval, size_t __user *oldlenp,
2373                 void __user *newval, size_t newlen, void **context)
2374 {
2375         if (oldval) {
2376                 size_t olen;
2377                 if (oldlenp) { 
2378                         if (get_user(olen, oldlenp))
2379                                 return -EFAULT;
2380                         if (olen!=sizeof(int))
2381                                 return -EINVAL; 
2382                 }
2383                 if (put_user(jiffies_to_msecs(*(int *)(table->data)), (int __user *)oldval) ||
2384                     (oldlenp && put_user(sizeof(int),oldlenp)))
2385                         return -EFAULT;
2386         }
2387         if (newval && newlen) { 
2388                 int new;
2389                 if (newlen != sizeof(int))
2390                         return -EINVAL; 
2391                 if (get_user(new, (int __user *)newval))
2392                         return -EFAULT;
2393                 *(int *)(table->data) = msecs_to_jiffies(new);
2394         }
2395         return 1;
2396 }
2397
2398 #else /* CONFIG_SYSCTL */
2399
2400
2401 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2402 {
2403         return -ENOSYS;
2404 }
2405
2406 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2407                   void __user *oldval, size_t __user *oldlenp,
2408                   void __user *newval, size_t newlen, void **context)
2409 {
2410         return -ENOSYS;
2411 }
2412
2413 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2414                 void __user *oldval, size_t __user *oldlenp,
2415                 void __user *newval, size_t newlen, void **context)
2416 {
2417         return -ENOSYS;
2418 }
2419
2420 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2421                 void __user *oldval, size_t __user *oldlenp,
2422                 void __user *newval, size_t newlen, void **context)
2423 {
2424         return -ENOSYS;
2425 }
2426
2427 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2428                 void __user *oldval, size_t __user *oldlenp,
2429                 void __user *newval, size_t newlen, void **context)
2430 {
2431         return -ENOSYS;
2432 }
2433
2434 int proc_dostring(ctl_table *table, int write, struct file *filp,
2435                   void __user *buffer, size_t *lenp, loff_t *ppos)
2436 {
2437         return -ENOSYS;
2438 }
2439
2440 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2441                   void __user *buffer, size_t *lenp, loff_t *ppos)
2442 {
2443         return -ENOSYS;
2444 }
2445
2446 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2447                         void __user *buffer, size_t *lenp, loff_t *ppos)
2448 {
2449         return -ENOSYS;
2450 }
2451
2452 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2453                     void __user *buffer, size_t *lenp, loff_t *ppos)
2454 {
2455         return -ENOSYS;
2456 }
2457
2458 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2459                           void __user *buffer, size_t *lenp, loff_t *ppos)
2460 {
2461         return -ENOSYS;
2462 }
2463
2464 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2465                           void __user *buffer, size_t *lenp, loff_t *ppos)
2466 {
2467         return -ENOSYS;
2468 }
2469
2470 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2471                              void __user *buffer, size_t *lenp, loff_t *ppos)
2472 {
2473         return -ENOSYS;
2474 }
2475
2476 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2477                     void __user *buffer, size_t *lenp, loff_t *ppos)
2478 {
2479         return -ENOSYS;
2480 }
2481
2482 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2483                                       struct file *filp,
2484                                       void __user *buffer,
2485                                       size_t *lenp, loff_t *ppos)
2486 {
2487     return -ENOSYS;
2488 }
2489
2490 struct ctl_table_header * register_sysctl_table(ctl_table * table, 
2491                                                 int insert_at_head)
2492 {
2493         return NULL;
2494 }
2495
2496 void unregister_sysctl_table(struct ctl_table_header * table)
2497 {
2498 }
2499
2500 #endif /* CONFIG_SYSCTL */
2501
2502 /*
2503  * No sense putting this after each symbol definition, twice,
2504  * exception granted :-)
2505  */
2506 EXPORT_SYMBOL(proc_dointvec);
2507 EXPORT_SYMBOL(proc_dointvec_jiffies);
2508 EXPORT_SYMBOL(proc_dointvec_minmax);
2509 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2510 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2511 EXPORT_SYMBOL(proc_dostring);
2512 EXPORT_SYMBOL(proc_doulongvec_minmax);
2513 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2514 EXPORT_SYMBOL(register_sysctl_table);
2515 EXPORT_SYMBOL(sysctl_intvec);
2516 EXPORT_SYMBOL(sysctl_jiffies);
2517 EXPORT_SYMBOL(sysctl_ms_jiffies);
2518 EXPORT_SYMBOL(sysctl_string);
2519 EXPORT_SYMBOL(unregister_sysctl_table);