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