2 * sysctl.c: General linux system control interface
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
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
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
21 #include <linux/module.h>
23 #include <linux/swap.h>
24 #include <linux/slab.h>
25 #include <linux/sysctl.h>
26 #include <linux/proc_fs.h>
27 #include <linux/capability.h>
28 #include <linux/ctype.h>
29 #include <linux/utsname.h>
30 #include <linux/smp_lock.h>
32 #include <linux/init.h>
33 #include <linux/kernel.h>
34 #include <linux/kobject.h>
35 #include <linux/net.h>
36 #include <linux/sysrq.h>
37 #include <linux/highuid.h>
38 #include <linux/writeback.h>
39 #include <linux/hugetlb.h>
40 #include <linux/security.h>
41 #include <linux/initrd.h>
42 #include <linux/times.h>
43 #include <linux/limits.h>
44 #include <linux/dcache.h>
45 #include <linux/syscalls.h>
46 #include <linux/nfs_fs.h>
47 #include <linux/acpi.h>
48 #include <linux/reboot.h>
50 #include <asm/uaccess.h>
51 #include <asm/processor.h>
55 #include <asm/stacktrace.h>
58 #if defined(CONFIG_SYSCTL)
60 /* External variables not in a header file. */
62 extern int print_fatal_signals
;
63 extern int sysctl_overcommit_memory
;
64 extern int sysctl_overcommit_ratio
;
65 extern int sysctl_panic_on_oom
;
66 extern int max_threads
;
67 extern int core_uses_pid
;
68 extern int suid_dumpable
;
69 extern char core_pattern
[];
71 extern int min_free_kbytes
;
72 extern int printk_ratelimit_jiffies
;
73 extern int printk_ratelimit_burst
;
74 extern int pid_max_min
, pid_max_max
;
75 extern int sysctl_drop_caches
;
76 extern int percpu_pagelist_fraction
;
77 extern int compat_log
;
78 extern int maps_protect
;
79 extern int sysctl_stat_interval
;
80 extern int audit_argv_kb
;
82 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
83 static int maxolduid
= 65535;
85 static int min_percpu_pagelist_fract
= 8;
87 static int ngroups_max
= NGROUPS_MAX
;
90 extern char modprobe_path
[];
92 #ifdef CONFIG_CHR_DEV_SG
93 extern int sg_big_buff
;
97 extern char reboot_command
[];
98 extern int stop_a_enabled
;
99 extern int scons_pwroff
;
103 extern int pwrsw_enabled
;
104 extern int unaligned_enabled
;
108 #ifdef CONFIG_MATHEMU
109 extern int sysctl_ieee_emulation_warnings
;
111 extern int sysctl_userprocess_debug
;
112 extern int spin_retry
;
115 extern int sysctl_hz_timer
;
117 #ifdef CONFIG_BSD_PROCESS_ACCT
118 extern int acct_parm
[];
122 extern int no_unaligned_warning
;
125 #ifdef CONFIG_RT_MUTEXES
126 extern int max_lock_depth
;
129 #ifdef CONFIG_SYSCTL_SYSCALL
130 static int parse_table(int __user
*, int, void __user
*, size_t __user
*,
131 void __user
*, size_t, ctl_table
*);
135 #ifdef CONFIG_PROC_SYSCTL
136 static int proc_do_cad_pid(ctl_table
*table
, int write
, struct file
*filp
,
137 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
138 static int proc_dointvec_taint(ctl_table
*table
, int write
, struct file
*filp
,
139 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
142 static ctl_table root_table
[];
143 static struct ctl_table_header root_table_header
=
144 { root_table
, LIST_HEAD_INIT(root_table_header
.ctl_entry
) };
146 static ctl_table kern_table
[];
147 static ctl_table vm_table
[];
148 static ctl_table fs_table
[];
149 static ctl_table debug_table
[];
150 static ctl_table dev_table
[];
151 extern ctl_table random_table
[];
152 #ifdef CONFIG_UNIX98_PTYS
153 extern ctl_table pty_table
[];
155 #ifdef CONFIG_INOTIFY_USER
156 extern ctl_table inotify_table
[];
159 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
160 int sysctl_legacy_va_layout
;
163 extern int prove_locking
;
164 extern int lock_stat
;
166 /* The default sysctl tables: */
168 static ctl_table root_table
[] = {
170 .ctl_name
= CTL_KERN
,
171 .procname
= "kernel",
196 .ctl_name
= CTL_DEBUG
,
199 .child
= debug_table
,
208 * NOTE: do not add new entries to this table unless you have read
209 * Documentation/sysctl/ctl_unnumbered.txt
214 #ifdef CONFIG_SCHED_DEBUG
215 static unsigned long min_sched_granularity_ns
= 100000; /* 100 usecs */
216 static unsigned long max_sched_granularity_ns
= 1000000000; /* 1 second */
217 static unsigned long min_wakeup_granularity_ns
; /* 0 usecs */
218 static unsigned long max_wakeup_granularity_ns
= 1000000000; /* 1 second */
221 static ctl_table kern_table
[] = {
222 #ifdef CONFIG_SCHED_DEBUG
224 .ctl_name
= CTL_UNNUMBERED
,
225 .procname
= "sched_nr_latency",
226 .data
= &sysctl_sched_nr_latency
,
227 .maxlen
= sizeof(unsigned int),
229 .proc_handler
= &proc_dointvec
,
232 .ctl_name
= CTL_UNNUMBERED
,
233 .procname
= "sched_latency_ns",
234 .data
= &sysctl_sched_latency
,
235 .maxlen
= sizeof(unsigned int),
237 .proc_handler
= &proc_dointvec_minmax
,
238 .strategy
= &sysctl_intvec
,
239 .extra1
= &min_sched_granularity_ns
,
240 .extra2
= &max_sched_granularity_ns
,
243 .ctl_name
= CTL_UNNUMBERED
,
244 .procname
= "sched_wakeup_granularity_ns",
245 .data
= &sysctl_sched_wakeup_granularity
,
246 .maxlen
= sizeof(unsigned int),
248 .proc_handler
= &proc_dointvec_minmax
,
249 .strategy
= &sysctl_intvec
,
250 .extra1
= &min_wakeup_granularity_ns
,
251 .extra2
= &max_wakeup_granularity_ns
,
254 .ctl_name
= CTL_UNNUMBERED
,
255 .procname
= "sched_batch_wakeup_granularity_ns",
256 .data
= &sysctl_sched_batch_wakeup_granularity
,
257 .maxlen
= sizeof(unsigned int),
259 .proc_handler
= &proc_dointvec_minmax
,
260 .strategy
= &sysctl_intvec
,
261 .extra1
= &min_wakeup_granularity_ns
,
262 .extra2
= &max_wakeup_granularity_ns
,
265 .ctl_name
= CTL_UNNUMBERED
,
266 .procname
= "sched_child_runs_first",
267 .data
= &sysctl_sched_child_runs_first
,
268 .maxlen
= sizeof(unsigned int),
270 .proc_handler
= &proc_dointvec
,
273 .ctl_name
= CTL_UNNUMBERED
,
274 .procname
= "sched_features",
275 .data
= &sysctl_sched_features
,
276 .maxlen
= sizeof(unsigned int),
278 .proc_handler
= &proc_dointvec
,
281 .ctl_name
= CTL_UNNUMBERED
,
282 .procname
= "sched_migration_cost",
283 .data
= &sysctl_sched_migration_cost
,
284 .maxlen
= sizeof(unsigned int),
286 .proc_handler
= &proc_dointvec
,
290 .ctl_name
= CTL_UNNUMBERED
,
291 .procname
= "sched_compat_yield",
292 .data
= &sysctl_sched_compat_yield
,
293 .maxlen
= sizeof(unsigned int),
295 .proc_handler
= &proc_dointvec
,
297 #ifdef CONFIG_PROVE_LOCKING
299 .ctl_name
= CTL_UNNUMBERED
,
300 .procname
= "prove_locking",
301 .data
= &prove_locking
,
302 .maxlen
= sizeof(int),
304 .proc_handler
= &proc_dointvec
,
307 #ifdef CONFIG_LOCK_STAT
309 .ctl_name
= CTL_UNNUMBERED
,
310 .procname
= "lock_stat",
312 .maxlen
= sizeof(int),
314 .proc_handler
= &proc_dointvec
,
318 .ctl_name
= KERN_PANIC
,
320 .data
= &panic_timeout
,
321 .maxlen
= sizeof(int),
323 .proc_handler
= &proc_dointvec
,
326 .ctl_name
= KERN_CORE_USES_PID
,
327 .procname
= "core_uses_pid",
328 .data
= &core_uses_pid
,
329 .maxlen
= sizeof(int),
331 .proc_handler
= &proc_dointvec
,
333 #ifdef CONFIG_AUDITSYSCALL
335 .ctl_name
= CTL_UNNUMBERED
,
336 .procname
= "audit_argv_kb",
337 .data
= &audit_argv_kb
,
338 .maxlen
= sizeof(int),
340 .proc_handler
= &proc_dointvec
,
344 .ctl_name
= KERN_CORE_PATTERN
,
345 .procname
= "core_pattern",
346 .data
= core_pattern
,
347 .maxlen
= CORENAME_MAX_SIZE
,
349 .proc_handler
= &proc_dostring
,
350 .strategy
= &sysctl_string
,
352 #ifdef CONFIG_PROC_SYSCTL
354 .ctl_name
= KERN_TAINTED
,
355 .procname
= "tainted",
357 .maxlen
= sizeof(int),
359 .proc_handler
= &proc_dointvec_taint
,
363 .ctl_name
= KERN_CAP_BSET
,
364 .procname
= "cap-bound",
366 .maxlen
= sizeof(kernel_cap_t
),
368 .proc_handler
= &proc_dointvec_bset
,
370 #ifdef CONFIG_BLK_DEV_INITRD
372 .ctl_name
= KERN_REALROOTDEV
,
373 .procname
= "real-root-dev",
374 .data
= &real_root_dev
,
375 .maxlen
= sizeof(int),
377 .proc_handler
= &proc_dointvec
,
381 .ctl_name
= CTL_UNNUMBERED
,
382 .procname
= "print-fatal-signals",
383 .data
= &print_fatal_signals
,
384 .maxlen
= sizeof(int),
386 .proc_handler
= &proc_dointvec
,
390 .ctl_name
= KERN_SPARC_REBOOT
,
391 .procname
= "reboot-cmd",
392 .data
= reboot_command
,
395 .proc_handler
= &proc_dostring
,
396 .strategy
= &sysctl_string
,
399 .ctl_name
= KERN_SPARC_STOP_A
,
400 .procname
= "stop-a",
401 .data
= &stop_a_enabled
,
402 .maxlen
= sizeof (int),
404 .proc_handler
= &proc_dointvec
,
407 .ctl_name
= KERN_SPARC_SCONS_PWROFF
,
408 .procname
= "scons-poweroff",
409 .data
= &scons_pwroff
,
410 .maxlen
= sizeof (int),
412 .proc_handler
= &proc_dointvec
,
417 .ctl_name
= KERN_HPPA_PWRSW
,
418 .procname
= "soft-power",
419 .data
= &pwrsw_enabled
,
420 .maxlen
= sizeof (int),
422 .proc_handler
= &proc_dointvec
,
425 .ctl_name
= KERN_HPPA_UNALIGNED
,
426 .procname
= "unaligned-trap",
427 .data
= &unaligned_enabled
,
428 .maxlen
= sizeof (int),
430 .proc_handler
= &proc_dointvec
,
434 .ctl_name
= KERN_CTLALTDEL
,
435 .procname
= "ctrl-alt-del",
437 .maxlen
= sizeof(int),
439 .proc_handler
= &proc_dointvec
,
442 .ctl_name
= KERN_PRINTK
,
443 .procname
= "printk",
444 .data
= &console_loglevel
,
445 .maxlen
= 4*sizeof(int),
447 .proc_handler
= &proc_dointvec
,
451 .ctl_name
= KERN_MODPROBE
,
452 .procname
= "modprobe",
453 .data
= &modprobe_path
,
454 .maxlen
= KMOD_PATH_LEN
,
456 .proc_handler
= &proc_dostring
,
457 .strategy
= &sysctl_string
,
460 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
462 .ctl_name
= KERN_HOTPLUG
,
463 .procname
= "hotplug",
464 .data
= &uevent_helper
,
465 .maxlen
= UEVENT_HELPER_PATH_LEN
,
467 .proc_handler
= &proc_dostring
,
468 .strategy
= &sysctl_string
,
471 #ifdef CONFIG_CHR_DEV_SG
473 .ctl_name
= KERN_SG_BIG_BUFF
,
474 .procname
= "sg-big-buff",
475 .data
= &sg_big_buff
,
476 .maxlen
= sizeof (int),
478 .proc_handler
= &proc_dointvec
,
481 #ifdef CONFIG_BSD_PROCESS_ACCT
483 .ctl_name
= KERN_ACCT
,
486 .maxlen
= 3*sizeof(int),
488 .proc_handler
= &proc_dointvec
,
491 #ifdef CONFIG_MAGIC_SYSRQ
493 .ctl_name
= KERN_SYSRQ
,
495 .data
= &__sysrq_enabled
,
496 .maxlen
= sizeof (int),
498 .proc_handler
= &proc_dointvec
,
501 #ifdef CONFIG_PROC_SYSCTL
503 .ctl_name
= KERN_CADPID
,
504 .procname
= "cad_pid",
506 .maxlen
= sizeof (int),
508 .proc_handler
= &proc_do_cad_pid
,
512 .ctl_name
= KERN_MAX_THREADS
,
513 .procname
= "threads-max",
514 .data
= &max_threads
,
515 .maxlen
= sizeof(int),
517 .proc_handler
= &proc_dointvec
,
520 .ctl_name
= KERN_RANDOM
,
521 .procname
= "random",
523 .child
= random_table
,
525 #ifdef CONFIG_UNIX98_PTYS
527 .ctl_name
= KERN_PTY
,
534 .ctl_name
= KERN_OVERFLOWUID
,
535 .procname
= "overflowuid",
536 .data
= &overflowuid
,
537 .maxlen
= sizeof(int),
539 .proc_handler
= &proc_dointvec_minmax
,
540 .strategy
= &sysctl_intvec
,
541 .extra1
= &minolduid
,
542 .extra2
= &maxolduid
,
545 .ctl_name
= KERN_OVERFLOWGID
,
546 .procname
= "overflowgid",
547 .data
= &overflowgid
,
548 .maxlen
= sizeof(int),
550 .proc_handler
= &proc_dointvec_minmax
,
551 .strategy
= &sysctl_intvec
,
552 .extra1
= &minolduid
,
553 .extra2
= &maxolduid
,
556 #ifdef CONFIG_MATHEMU
558 .ctl_name
= KERN_IEEE_EMULATION_WARNINGS
,
559 .procname
= "ieee_emulation_warnings",
560 .data
= &sysctl_ieee_emulation_warnings
,
561 .maxlen
= sizeof(int),
563 .proc_handler
= &proc_dointvec
,
566 #ifdef CONFIG_NO_IDLE_HZ
568 .ctl_name
= KERN_HZ_TIMER
,
569 .procname
= "hz_timer",
570 .data
= &sysctl_hz_timer
,
571 .maxlen
= sizeof(int),
573 .proc_handler
= &proc_dointvec
,
577 .ctl_name
= KERN_S390_USER_DEBUG_LOGGING
,
578 .procname
= "userprocess_debug",
579 .data
= &sysctl_userprocess_debug
,
580 .maxlen
= sizeof(int),
582 .proc_handler
= &proc_dointvec
,
586 .ctl_name
= KERN_PIDMAX
,
587 .procname
= "pid_max",
589 .maxlen
= sizeof (int),
591 .proc_handler
= &proc_dointvec_minmax
,
592 .strategy
= sysctl_intvec
,
593 .extra1
= &pid_max_min
,
594 .extra2
= &pid_max_max
,
597 .ctl_name
= KERN_PANIC_ON_OOPS
,
598 .procname
= "panic_on_oops",
599 .data
= &panic_on_oops
,
600 .maxlen
= sizeof(int),
602 .proc_handler
= &proc_dointvec
,
605 .ctl_name
= KERN_PRINTK_RATELIMIT
,
606 .procname
= "printk_ratelimit",
607 .data
= &printk_ratelimit_jiffies
,
608 .maxlen
= sizeof(int),
610 .proc_handler
= &proc_dointvec_jiffies
,
611 .strategy
= &sysctl_jiffies
,
614 .ctl_name
= KERN_PRINTK_RATELIMIT_BURST
,
615 .procname
= "printk_ratelimit_burst",
616 .data
= &printk_ratelimit_burst
,
617 .maxlen
= sizeof(int),
619 .proc_handler
= &proc_dointvec
,
622 .ctl_name
= KERN_NGROUPS_MAX
,
623 .procname
= "ngroups_max",
624 .data
= &ngroups_max
,
625 .maxlen
= sizeof (int),
627 .proc_handler
= &proc_dointvec
,
629 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
631 .ctl_name
= KERN_UNKNOWN_NMI_PANIC
,
632 .procname
= "unknown_nmi_panic",
633 .data
= &unknown_nmi_panic
,
634 .maxlen
= sizeof (int),
636 .proc_handler
= &proc_dointvec
,
639 .ctl_name
= KERN_NMI_WATCHDOG
,
640 .procname
= "nmi_watchdog",
641 .data
= &nmi_watchdog_enabled
,
642 .maxlen
= sizeof (int),
644 .proc_handler
= &proc_nmi_enabled
,
647 #if defined(CONFIG_X86)
649 .ctl_name
= KERN_PANIC_ON_NMI
,
650 .procname
= "panic_on_unrecovered_nmi",
651 .data
= &panic_on_unrecovered_nmi
,
652 .maxlen
= sizeof(int),
654 .proc_handler
= &proc_dointvec
,
657 .ctl_name
= KERN_BOOTLOADER_TYPE
,
658 .procname
= "bootloader_type",
659 .data
= &bootloader_type
,
660 .maxlen
= sizeof (int),
662 .proc_handler
= &proc_dointvec
,
665 .ctl_name
= CTL_UNNUMBERED
,
666 .procname
= "kstack_depth_to_print",
667 .data
= &kstack_depth_to_print
,
668 .maxlen
= sizeof(int),
670 .proc_handler
= &proc_dointvec
,
673 #if defined(CONFIG_MMU)
675 .ctl_name
= KERN_RANDOMIZE
,
676 .procname
= "randomize_va_space",
677 .data
= &randomize_va_space
,
678 .maxlen
= sizeof(int),
680 .proc_handler
= &proc_dointvec
,
683 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
685 .ctl_name
= KERN_SPIN_RETRY
,
686 .procname
= "spin_retry",
688 .maxlen
= sizeof (int),
690 .proc_handler
= &proc_dointvec
,
693 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
695 .ctl_name
= KERN_ACPI_VIDEO_FLAGS
,
696 .procname
= "acpi_video_flags",
697 .data
= &acpi_realmode_flags
,
698 .maxlen
= sizeof (unsigned long),
700 .proc_handler
= &proc_doulongvec_minmax
,
705 .ctl_name
= KERN_IA64_UNALIGNED
,
706 .procname
= "ignore-unaligned-usertrap",
707 .data
= &no_unaligned_warning
,
708 .maxlen
= sizeof (int),
710 .proc_handler
= &proc_dointvec
,
715 .ctl_name
= KERN_COMPAT_LOG
,
716 .procname
= "compat-log",
718 .maxlen
= sizeof (int),
720 .proc_handler
= &proc_dointvec
,
723 #ifdef CONFIG_RT_MUTEXES
725 .ctl_name
= KERN_MAX_LOCK_DEPTH
,
726 .procname
= "max_lock_depth",
727 .data
= &max_lock_depth
,
728 .maxlen
= sizeof(int),
730 .proc_handler
= &proc_dointvec
,
733 #ifdef CONFIG_PROC_FS
735 .ctl_name
= CTL_UNNUMBERED
,
736 .procname
= "maps_protect",
737 .data
= &maps_protect
,
738 .maxlen
= sizeof(int),
740 .proc_handler
= &proc_dointvec
,
744 .ctl_name
= CTL_UNNUMBERED
,
745 .procname
= "poweroff_cmd",
746 .data
= &poweroff_cmd
,
747 .maxlen
= POWEROFF_CMD_PATH_LEN
,
749 .proc_handler
= &proc_dostring
,
750 .strategy
= &sysctl_string
,
753 * NOTE: do not add new entries to this table unless you have read
754 * Documentation/sysctl/ctl_unnumbered.txt
759 /* Constants for minimum and maximum testing in vm_table.
760 We use these as one-element integer vectors. */
763 static int one_hundred
= 100;
766 static ctl_table vm_table
[] = {
768 .ctl_name
= VM_OVERCOMMIT_MEMORY
,
769 .procname
= "overcommit_memory",
770 .data
= &sysctl_overcommit_memory
,
771 .maxlen
= sizeof(sysctl_overcommit_memory
),
773 .proc_handler
= &proc_dointvec
,
776 .ctl_name
= VM_PANIC_ON_OOM
,
777 .procname
= "panic_on_oom",
778 .data
= &sysctl_panic_on_oom
,
779 .maxlen
= sizeof(sysctl_panic_on_oom
),
781 .proc_handler
= &proc_dointvec
,
784 .ctl_name
= VM_OVERCOMMIT_RATIO
,
785 .procname
= "overcommit_ratio",
786 .data
= &sysctl_overcommit_ratio
,
787 .maxlen
= sizeof(sysctl_overcommit_ratio
),
789 .proc_handler
= &proc_dointvec
,
792 .ctl_name
= VM_PAGE_CLUSTER
,
793 .procname
= "page-cluster",
794 .data
= &page_cluster
,
795 .maxlen
= sizeof(int),
797 .proc_handler
= &proc_dointvec
,
800 .ctl_name
= VM_DIRTY_BACKGROUND
,
801 .procname
= "dirty_background_ratio",
802 .data
= &dirty_background_ratio
,
803 .maxlen
= sizeof(dirty_background_ratio
),
805 .proc_handler
= &proc_dointvec_minmax
,
806 .strategy
= &sysctl_intvec
,
808 .extra2
= &one_hundred
,
811 .ctl_name
= VM_DIRTY_RATIO
,
812 .procname
= "dirty_ratio",
813 .data
= &vm_dirty_ratio
,
814 .maxlen
= sizeof(vm_dirty_ratio
),
816 .proc_handler
= &proc_dointvec_minmax
,
817 .strategy
= &sysctl_intvec
,
819 .extra2
= &one_hundred
,
822 .ctl_name
= VM_DIRTY_WB_CS
,
823 .procname
= "dirty_writeback_centisecs",
824 .data
= &dirty_writeback_interval
,
825 .maxlen
= sizeof(dirty_writeback_interval
),
827 .proc_handler
= &dirty_writeback_centisecs_handler
,
830 .ctl_name
= VM_DIRTY_EXPIRE_CS
,
831 .procname
= "dirty_expire_centisecs",
832 .data
= &dirty_expire_interval
,
833 .maxlen
= sizeof(dirty_expire_interval
),
835 .proc_handler
= &proc_dointvec_userhz_jiffies
,
838 .ctl_name
= VM_NR_PDFLUSH_THREADS
,
839 .procname
= "nr_pdflush_threads",
840 .data
= &nr_pdflush_threads
,
841 .maxlen
= sizeof nr_pdflush_threads
,
842 .mode
= 0444 /* read-only*/,
843 .proc_handler
= &proc_dointvec
,
846 .ctl_name
= VM_SWAPPINESS
,
847 .procname
= "swappiness",
848 .data
= &vm_swappiness
,
849 .maxlen
= sizeof(vm_swappiness
),
851 .proc_handler
= &proc_dointvec_minmax
,
852 .strategy
= &sysctl_intvec
,
854 .extra2
= &one_hundred
,
856 #ifdef CONFIG_HUGETLB_PAGE
858 .ctl_name
= VM_HUGETLB_PAGES
,
859 .procname
= "nr_hugepages",
860 .data
= &max_huge_pages
,
861 .maxlen
= sizeof(unsigned long),
863 .proc_handler
= &hugetlb_sysctl_handler
,
864 .extra1
= (void *)&hugetlb_zero
,
865 .extra2
= (void *)&hugetlb_infinity
,
868 .ctl_name
= VM_HUGETLB_GROUP
,
869 .procname
= "hugetlb_shm_group",
870 .data
= &sysctl_hugetlb_shm_group
,
871 .maxlen
= sizeof(gid_t
),
873 .proc_handler
= &proc_dointvec
,
876 .ctl_name
= CTL_UNNUMBERED
,
877 .procname
= "hugepages_treat_as_movable",
878 .data
= &hugepages_treat_as_movable
,
879 .maxlen
= sizeof(int),
881 .proc_handler
= &hugetlb_treat_movable_handler
,
885 .ctl_name
= VM_LOWMEM_RESERVE_RATIO
,
886 .procname
= "lowmem_reserve_ratio",
887 .data
= &sysctl_lowmem_reserve_ratio
,
888 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
890 .proc_handler
= &lowmem_reserve_ratio_sysctl_handler
,
891 .strategy
= &sysctl_intvec
,
894 .ctl_name
= VM_DROP_PAGECACHE
,
895 .procname
= "drop_caches",
896 .data
= &sysctl_drop_caches
,
897 .maxlen
= sizeof(int),
899 .proc_handler
= drop_caches_sysctl_handler
,
900 .strategy
= &sysctl_intvec
,
903 .ctl_name
= VM_MIN_FREE_KBYTES
,
904 .procname
= "min_free_kbytes",
905 .data
= &min_free_kbytes
,
906 .maxlen
= sizeof(min_free_kbytes
),
908 .proc_handler
= &min_free_kbytes_sysctl_handler
,
909 .strategy
= &sysctl_intvec
,
913 .ctl_name
= VM_PERCPU_PAGELIST_FRACTION
,
914 .procname
= "percpu_pagelist_fraction",
915 .data
= &percpu_pagelist_fraction
,
916 .maxlen
= sizeof(percpu_pagelist_fraction
),
918 .proc_handler
= &percpu_pagelist_fraction_sysctl_handler
,
919 .strategy
= &sysctl_intvec
,
920 .extra1
= &min_percpu_pagelist_fract
,
924 .ctl_name
= VM_MAX_MAP_COUNT
,
925 .procname
= "max_map_count",
926 .data
= &sysctl_max_map_count
,
927 .maxlen
= sizeof(sysctl_max_map_count
),
929 .proc_handler
= &proc_dointvec
933 .ctl_name
= VM_LAPTOP_MODE
,
934 .procname
= "laptop_mode",
935 .data
= &laptop_mode
,
936 .maxlen
= sizeof(laptop_mode
),
938 .proc_handler
= &proc_dointvec_jiffies
,
939 .strategy
= &sysctl_jiffies
,
942 .ctl_name
= VM_BLOCK_DUMP
,
943 .procname
= "block_dump",
945 .maxlen
= sizeof(block_dump
),
947 .proc_handler
= &proc_dointvec
,
948 .strategy
= &sysctl_intvec
,
952 .ctl_name
= VM_VFS_CACHE_PRESSURE
,
953 .procname
= "vfs_cache_pressure",
954 .data
= &sysctl_vfs_cache_pressure
,
955 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
957 .proc_handler
= &proc_dointvec
,
958 .strategy
= &sysctl_intvec
,
961 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
963 .ctl_name
= VM_LEGACY_VA_LAYOUT
,
964 .procname
= "legacy_va_layout",
965 .data
= &sysctl_legacy_va_layout
,
966 .maxlen
= sizeof(sysctl_legacy_va_layout
),
968 .proc_handler
= &proc_dointvec
,
969 .strategy
= &sysctl_intvec
,
975 .ctl_name
= VM_ZONE_RECLAIM_MODE
,
976 .procname
= "zone_reclaim_mode",
977 .data
= &zone_reclaim_mode
,
978 .maxlen
= sizeof(zone_reclaim_mode
),
980 .proc_handler
= &proc_dointvec
,
981 .strategy
= &sysctl_intvec
,
985 .ctl_name
= VM_MIN_UNMAPPED
,
986 .procname
= "min_unmapped_ratio",
987 .data
= &sysctl_min_unmapped_ratio
,
988 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
990 .proc_handler
= &sysctl_min_unmapped_ratio_sysctl_handler
,
991 .strategy
= &sysctl_intvec
,
993 .extra2
= &one_hundred
,
996 .ctl_name
= VM_MIN_SLAB
,
997 .procname
= "min_slab_ratio",
998 .data
= &sysctl_min_slab_ratio
,
999 .maxlen
= sizeof(sysctl_min_slab_ratio
),
1001 .proc_handler
= &sysctl_min_slab_ratio_sysctl_handler
,
1002 .strategy
= &sysctl_intvec
,
1004 .extra2
= &one_hundred
,
1009 .ctl_name
= CTL_UNNUMBERED
,
1010 .procname
= "stat_interval",
1011 .data
= &sysctl_stat_interval
,
1012 .maxlen
= sizeof(sysctl_stat_interval
),
1014 .proc_handler
= &proc_dointvec_jiffies
,
1015 .strategy
= &sysctl_jiffies
,
1018 #ifdef CONFIG_SECURITY
1020 .ctl_name
= CTL_UNNUMBERED
,
1021 .procname
= "mmap_min_addr",
1022 .data
= &mmap_min_addr
,
1023 .maxlen
= sizeof(unsigned long),
1025 .proc_handler
= &proc_doulongvec_minmax
,
1030 .ctl_name
= CTL_UNNUMBERED
,
1031 .procname
= "numa_zonelist_order",
1032 .data
= &numa_zonelist_order
,
1033 .maxlen
= NUMA_ZONELIST_ORDER_LEN
,
1035 .proc_handler
= &numa_zonelist_order_handler
,
1036 .strategy
= &sysctl_string
,
1039 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1040 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1042 .ctl_name
= VM_VDSO_ENABLED
,
1043 .procname
= "vdso_enabled",
1044 .data
= &vdso_enabled
,
1045 .maxlen
= sizeof(vdso_enabled
),
1047 .proc_handler
= &proc_dointvec
,
1048 .strategy
= &sysctl_intvec
,
1053 * NOTE: do not add new entries to this table unless you have read
1054 * Documentation/sysctl/ctl_unnumbered.txt
1059 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1060 static ctl_table binfmt_misc_table
[] = {
1065 static ctl_table fs_table
[] = {
1067 .ctl_name
= FS_NRINODE
,
1068 .procname
= "inode-nr",
1069 .data
= &inodes_stat
,
1070 .maxlen
= 2*sizeof(int),
1072 .proc_handler
= &proc_dointvec
,
1075 .ctl_name
= FS_STATINODE
,
1076 .procname
= "inode-state",
1077 .data
= &inodes_stat
,
1078 .maxlen
= 7*sizeof(int),
1080 .proc_handler
= &proc_dointvec
,
1083 .ctl_name
= FS_NRFILE
,
1084 .procname
= "file-nr",
1085 .data
= &files_stat
,
1086 .maxlen
= 3*sizeof(int),
1088 .proc_handler
= &proc_nr_files
,
1091 .ctl_name
= FS_MAXFILE
,
1092 .procname
= "file-max",
1093 .data
= &files_stat
.max_files
,
1094 .maxlen
= sizeof(int),
1096 .proc_handler
= &proc_dointvec
,
1099 .ctl_name
= FS_DENTRY
,
1100 .procname
= "dentry-state",
1101 .data
= &dentry_stat
,
1102 .maxlen
= 6*sizeof(int),
1104 .proc_handler
= &proc_dointvec
,
1107 .ctl_name
= FS_OVERFLOWUID
,
1108 .procname
= "overflowuid",
1109 .data
= &fs_overflowuid
,
1110 .maxlen
= sizeof(int),
1112 .proc_handler
= &proc_dointvec_minmax
,
1113 .strategy
= &sysctl_intvec
,
1114 .extra1
= &minolduid
,
1115 .extra2
= &maxolduid
,
1118 .ctl_name
= FS_OVERFLOWGID
,
1119 .procname
= "overflowgid",
1120 .data
= &fs_overflowgid
,
1121 .maxlen
= sizeof(int),
1123 .proc_handler
= &proc_dointvec_minmax
,
1124 .strategy
= &sysctl_intvec
,
1125 .extra1
= &minolduid
,
1126 .extra2
= &maxolduid
,
1129 .ctl_name
= FS_LEASES
,
1130 .procname
= "leases-enable",
1131 .data
= &leases_enable
,
1132 .maxlen
= sizeof(int),
1134 .proc_handler
= &proc_dointvec
,
1136 #ifdef CONFIG_DNOTIFY
1138 .ctl_name
= FS_DIR_NOTIFY
,
1139 .procname
= "dir-notify-enable",
1140 .data
= &dir_notify_enable
,
1141 .maxlen
= sizeof(int),
1143 .proc_handler
= &proc_dointvec
,
1148 .ctl_name
= FS_LEASE_TIME
,
1149 .procname
= "lease-break-time",
1150 .data
= &lease_break_time
,
1151 .maxlen
= sizeof(int),
1153 .proc_handler
= &proc_dointvec_minmax
,
1154 .strategy
= &sysctl_intvec
,
1159 .ctl_name
= FS_AIO_NR
,
1160 .procname
= "aio-nr",
1162 .maxlen
= sizeof(aio_nr
),
1164 .proc_handler
= &proc_doulongvec_minmax
,
1167 .ctl_name
= FS_AIO_MAX_NR
,
1168 .procname
= "aio-max-nr",
1169 .data
= &aio_max_nr
,
1170 .maxlen
= sizeof(aio_max_nr
),
1172 .proc_handler
= &proc_doulongvec_minmax
,
1174 #ifdef CONFIG_INOTIFY_USER
1176 .ctl_name
= FS_INOTIFY
,
1177 .procname
= "inotify",
1179 .child
= inotify_table
,
1184 .ctl_name
= KERN_SETUID_DUMPABLE
,
1185 .procname
= "suid_dumpable",
1186 .data
= &suid_dumpable
,
1187 .maxlen
= sizeof(int),
1189 .proc_handler
= &proc_dointvec
,
1191 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1193 .ctl_name
= CTL_UNNUMBERED
,
1194 .procname
= "binfmt_misc",
1196 .child
= binfmt_misc_table
,
1200 * NOTE: do not add new entries to this table unless you have read
1201 * Documentation/sysctl/ctl_unnumbered.txt
1206 static ctl_table debug_table
[] = {
1207 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1209 .ctl_name
= CTL_UNNUMBERED
,
1210 .procname
= "exception-trace",
1211 .data
= &show_unhandled_signals
,
1212 .maxlen
= sizeof(int),
1214 .proc_handler
= proc_dointvec
1220 static ctl_table dev_table
[] = {
1224 static DEFINE_SPINLOCK(sysctl_lock
);
1226 /* called under sysctl_lock */
1227 static int use_table(struct ctl_table_header
*p
)
1229 if (unlikely(p
->unregistering
))
1235 /* called under sysctl_lock */
1236 static void unuse_table(struct ctl_table_header
*p
)
1239 if (unlikely(p
->unregistering
))
1240 complete(p
->unregistering
);
1243 /* called under sysctl_lock, will reacquire if has to wait */
1244 static void start_unregistering(struct ctl_table_header
*p
)
1247 * if p->used is 0, nobody will ever touch that entry again;
1248 * we'll eliminate all paths to it before dropping sysctl_lock
1250 if (unlikely(p
->used
)) {
1251 struct completion wait
;
1252 init_completion(&wait
);
1253 p
->unregistering
= &wait
;
1254 spin_unlock(&sysctl_lock
);
1255 wait_for_completion(&wait
);
1256 spin_lock(&sysctl_lock
);
1259 * do not remove from the list until nobody holds it; walking the
1260 * list in do_sysctl() relies on that.
1262 list_del_init(&p
->ctl_entry
);
1265 void sysctl_head_finish(struct ctl_table_header
*head
)
1269 spin_lock(&sysctl_lock
);
1271 spin_unlock(&sysctl_lock
);
1274 struct ctl_table_header
*sysctl_head_next(struct ctl_table_header
*prev
)
1276 struct ctl_table_header
*head
;
1277 struct list_head
*tmp
;
1278 spin_lock(&sysctl_lock
);
1280 tmp
= &prev
->ctl_entry
;
1284 tmp
= &root_table_header
.ctl_entry
;
1286 head
= list_entry(tmp
, struct ctl_table_header
, ctl_entry
);
1288 if (!use_table(head
))
1290 spin_unlock(&sysctl_lock
);
1294 if (tmp
== &root_table_header
.ctl_entry
)
1297 spin_unlock(&sysctl_lock
);
1301 #ifdef CONFIG_SYSCTL_SYSCALL
1302 int do_sysctl(int __user
*name
, int nlen
, void __user
*oldval
, size_t __user
*oldlenp
,
1303 void __user
*newval
, size_t newlen
)
1305 struct ctl_table_header
*head
;
1306 int error
= -ENOTDIR
;
1308 if (nlen
<= 0 || nlen
>= CTL_MAXNAME
)
1312 if (!oldlenp
|| get_user(old_len
, oldlenp
))
1316 for (head
= sysctl_head_next(NULL
); head
;
1317 head
= sysctl_head_next(head
)) {
1318 error
= parse_table(name
, nlen
, oldval
, oldlenp
,
1319 newval
, newlen
, head
->ctl_table
);
1320 if (error
!= -ENOTDIR
) {
1321 sysctl_head_finish(head
);
1328 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
1330 struct __sysctl_args tmp
;
1333 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
1337 error
= do_sysctl(tmp
.name
, tmp
.nlen
, tmp
.oldval
, tmp
.oldlenp
,
1338 tmp
.newval
, tmp
.newlen
);
1342 #endif /* CONFIG_SYSCTL_SYSCALL */
1345 * sysctl_perm does NOT grant the superuser all rights automatically, because
1346 * some sysctl variables are readonly even to root.
1349 static int test_perm(int mode
, int op
)
1353 else if (in_egroup_p(0))
1355 if ((mode
& op
& 0007) == op
)
1360 int sysctl_perm(ctl_table
*table
, int op
)
1363 error
= security_sysctl(table
, op
);
1366 return test_perm(table
->mode
, op
);
1369 #ifdef CONFIG_SYSCTL_SYSCALL
1370 static int parse_table(int __user
*name
, int nlen
,
1371 void __user
*oldval
, size_t __user
*oldlenp
,
1372 void __user
*newval
, size_t newlen
,
1379 if (get_user(n
, name
))
1381 for ( ; table
->ctl_name
|| table
->procname
; table
++) {
1382 if (!table
->ctl_name
)
1384 if (n
== table
->ctl_name
) {
1387 if (sysctl_perm(table
, 001))
1391 table
= table
->child
;
1394 error
= do_sysctl_strategy(table
, name
, nlen
,
1403 /* Perform the actual read/write of a sysctl table entry. */
1404 int do_sysctl_strategy (ctl_table
*table
,
1405 int __user
*name
, int nlen
,
1406 void __user
*oldval
, size_t __user
*oldlenp
,
1407 void __user
*newval
, size_t newlen
)
1416 if (sysctl_perm(table
, op
))
1419 if (table
->strategy
) {
1420 rc
= table
->strategy(table
, name
, nlen
, oldval
, oldlenp
,
1428 /* If there is no strategy routine, or if the strategy returns
1429 * zero, proceed with automatic r/w */
1430 if (table
->data
&& table
->maxlen
) {
1431 if (oldval
&& oldlenp
) {
1432 if (get_user(len
, oldlenp
))
1435 if (len
> table
->maxlen
)
1436 len
= table
->maxlen
;
1437 if(copy_to_user(oldval
, table
->data
, len
))
1439 if(put_user(len
, oldlenp
))
1443 if (newval
&& newlen
) {
1445 if (len
> table
->maxlen
)
1446 len
= table
->maxlen
;
1447 if(copy_from_user(table
->data
, newval
, len
))
1453 #endif /* CONFIG_SYSCTL_SYSCALL */
1455 static void sysctl_set_parent(struct ctl_table
*parent
, struct ctl_table
*table
)
1457 for (; table
->ctl_name
|| table
->procname
; table
++) {
1458 table
->parent
= parent
;
1460 sysctl_set_parent(table
, table
->child
);
1464 static __init
int sysctl_init(void)
1466 sysctl_set_parent(NULL
, root_table
);
1470 core_initcall(sysctl_init
);
1473 * register_sysctl_table - register a sysctl hierarchy
1474 * @table: the top-level table structure
1476 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1477 * array. An entry with a ctl_name of 0 terminates the table.
1479 * The members of the &ctl_table structure are used as follows:
1481 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1482 * must be unique within that level of sysctl
1484 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1485 * enter a sysctl file
1487 * data - a pointer to data for use by proc_handler
1489 * maxlen - the maximum size in bytes of the data
1491 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1493 * child - a pointer to the child sysctl table if this entry is a directory, or
1496 * proc_handler - the text handler routine (described below)
1498 * strategy - the strategy routine (described below)
1500 * de - for internal use by the sysctl routines
1502 * extra1, extra2 - extra pointers usable by the proc handler routines
1504 * Leaf nodes in the sysctl tree will be represented by a single file
1505 * under /proc; non-leaf nodes will be represented by directories.
1507 * sysctl(2) can automatically manage read and write requests through
1508 * the sysctl table. The data and maxlen fields of the ctl_table
1509 * struct enable minimal validation of the values being written to be
1510 * performed, and the mode field allows minimal authentication.
1512 * More sophisticated management can be enabled by the provision of a
1513 * strategy routine with the table entry. This will be called before
1514 * any automatic read or write of the data is performed.
1516 * The strategy routine may return
1518 * < 0 - Error occurred (error is passed to user process)
1520 * 0 - OK - proceed with automatic read or write.
1522 * > 0 - OK - read or write has been done by the strategy routine, so
1523 * return immediately.
1525 * There must be a proc_handler routine for any terminal nodes
1526 * mirrored under /proc/sys (non-terminals are handled by a built-in
1527 * directory handler). Several default handlers are available to
1528 * cover common cases -
1530 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1531 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1532 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1534 * It is the handler's job to read the input buffer from user memory
1535 * and process it. The handler should return 0 on success.
1537 * This routine returns %NULL on a failure to register, and a pointer
1538 * to the table header on success.
1540 struct ctl_table_header
*register_sysctl_table(ctl_table
* table
)
1542 struct ctl_table_header
*tmp
;
1543 tmp
= kmalloc(sizeof(struct ctl_table_header
), GFP_KERNEL
);
1546 tmp
->ctl_table
= table
;
1547 INIT_LIST_HEAD(&tmp
->ctl_entry
);
1549 tmp
->unregistering
= NULL
;
1550 sysctl_set_parent(NULL
, table
);
1551 spin_lock(&sysctl_lock
);
1552 list_add_tail(&tmp
->ctl_entry
, &root_table_header
.ctl_entry
);
1553 spin_unlock(&sysctl_lock
);
1558 * unregister_sysctl_table - unregister a sysctl table hierarchy
1559 * @header: the header returned from register_sysctl_table
1561 * Unregisters the sysctl table and all children. proc entries may not
1562 * actually be removed until they are no longer used by anyone.
1564 void unregister_sysctl_table(struct ctl_table_header
* header
)
1567 spin_lock(&sysctl_lock
);
1568 start_unregistering(header
);
1569 spin_unlock(&sysctl_lock
);
1573 #else /* !CONFIG_SYSCTL */
1574 struct ctl_table_header
*register_sysctl_table(ctl_table
* table
)
1579 void unregister_sysctl_table(struct ctl_table_header
* table
)
1583 #endif /* CONFIG_SYSCTL */
1589 #ifdef CONFIG_PROC_SYSCTL
1591 static int _proc_do_string(void* data
, int maxlen
, int write
,
1592 struct file
*filp
, void __user
*buffer
,
1593 size_t *lenp
, loff_t
*ppos
)
1599 if (!data
|| !maxlen
|| !*lenp
) {
1607 while (len
< *lenp
) {
1608 if (get_user(c
, p
++))
1610 if (c
== 0 || c
== '\n')
1616 if(copy_from_user(data
, buffer
, len
))
1618 ((char *) data
)[len
] = 0;
1636 if(copy_to_user(buffer
, data
, len
))
1639 if(put_user('\n', ((char __user
*) buffer
) + len
))
1650 * proc_dostring - read a string sysctl
1651 * @table: the sysctl table
1652 * @write: %TRUE if this is a write to the sysctl file
1653 * @filp: the file structure
1654 * @buffer: the user buffer
1655 * @lenp: the size of the user buffer
1656 * @ppos: file position
1658 * Reads/writes a string from/to the user buffer. If the kernel
1659 * buffer provided is not large enough to hold the string, the
1660 * string is truncated. The copied string is %NULL-terminated.
1661 * If the string is being read by the user process, it is copied
1662 * and a newline '\n' is added. It is truncated if the buffer is
1665 * Returns 0 on success.
1667 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
1668 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1670 return _proc_do_string(table
->data
, table
->maxlen
, write
, filp
,
1671 buffer
, lenp
, ppos
);
1675 static int do_proc_dointvec_conv(int *negp
, unsigned long *lvalp
,
1677 int write
, void *data
)
1680 *valp
= *negp
? -*lvalp
: *lvalp
;
1685 *lvalp
= (unsigned long)-val
;
1688 *lvalp
= (unsigned long)val
;
1694 static int __do_proc_dointvec(void *tbl_data
, ctl_table
*table
,
1695 int write
, struct file
*filp
, void __user
*buffer
,
1696 size_t *lenp
, loff_t
*ppos
,
1697 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1698 int write
, void *data
),
1701 #define TMPBUFLEN 21
1702 int *i
, vleft
, first
=1, neg
, val
;
1706 char buf
[TMPBUFLEN
], *p
;
1707 char __user
*s
= buffer
;
1709 if (!tbl_data
|| !table
->maxlen
|| !*lenp
||
1710 (*ppos
&& !write
)) {
1715 i
= (int *) tbl_data
;
1716 vleft
= table
->maxlen
/ sizeof(*i
);
1720 conv
= do_proc_dointvec_conv
;
1722 for (; left
&& vleft
--; i
++, first
=0) {
1737 if (len
> sizeof(buf
) - 1)
1738 len
= sizeof(buf
) - 1;
1739 if (copy_from_user(buf
, s
, len
))
1743 if (*p
== '-' && left
> 1) {
1747 if (*p
< '0' || *p
> '9')
1750 lval
= simple_strtoul(p
, &p
, 0);
1753 if ((len
< left
) && *p
&& !isspace(*p
))
1760 if (conv(&neg
, &lval
, i
, 1, data
))
1767 if (conv(&neg
, &lval
, i
, 0, data
))
1770 sprintf(p
, "%s%lu", neg
? "-" : "", lval
);
1774 if(copy_to_user(s
, buf
, len
))
1781 if (!write
&& !first
&& left
) {
1782 if(put_user('\n', s
))
1789 if (get_user(c
, s
++))
1804 static int do_proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1805 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
1806 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1807 int write
, void *data
),
1810 return __do_proc_dointvec(table
->data
, table
, write
, filp
,
1811 buffer
, lenp
, ppos
, conv
, data
);
1815 * proc_dointvec - read a vector of integers
1816 * @table: the sysctl table
1817 * @write: %TRUE if this is a write to the sysctl file
1818 * @filp: the file structure
1819 * @buffer: the user buffer
1820 * @lenp: the size of the user buffer
1821 * @ppos: file position
1823 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1824 * values from/to the user buffer, treated as an ASCII string.
1826 * Returns 0 on success.
1828 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1829 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1831 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1839 static int do_proc_dointvec_bset_conv(int *negp
, unsigned long *lvalp
,
1841 int write
, void *data
)
1843 int op
= *(int *)data
;
1845 int val
= *negp
? -*lvalp
: *lvalp
;
1847 case OP_SET
: *valp
= val
; break;
1848 case OP_AND
: *valp
&= val
; break;
1849 case OP_OR
: *valp
|= val
; break;
1855 *lvalp
= (unsigned long)-val
;
1858 *lvalp
= (unsigned long)val
;
1865 * init may raise the set.
1868 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
1869 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1873 if (write
&& !capable(CAP_SYS_MODULE
)) {
1877 op
= is_init(current
) ? OP_SET
: OP_AND
;
1878 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1879 do_proc_dointvec_bset_conv
,&op
);
1883 * Taint values can only be increased
1885 static int proc_dointvec_taint(ctl_table
*table
, int write
, struct file
*filp
,
1886 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1890 if (write
&& !capable(CAP_SYS_ADMIN
))
1894 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1895 do_proc_dointvec_bset_conv
,&op
);
1898 struct do_proc_dointvec_minmax_conv_param
{
1903 static int do_proc_dointvec_minmax_conv(int *negp
, unsigned long *lvalp
,
1905 int write
, void *data
)
1907 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
1909 int val
= *negp
? -*lvalp
: *lvalp
;
1910 if ((param
->min
&& *param
->min
> val
) ||
1911 (param
->max
&& *param
->max
< val
))
1918 *lvalp
= (unsigned long)-val
;
1921 *lvalp
= (unsigned long)val
;
1928 * proc_dointvec_minmax - read a vector of integers with min/max values
1929 * @table: the sysctl table
1930 * @write: %TRUE if this is a write to the sysctl file
1931 * @filp: the file structure
1932 * @buffer: the user buffer
1933 * @lenp: the size of the user buffer
1934 * @ppos: file position
1936 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1937 * values from/to the user buffer, treated as an ASCII string.
1939 * This routine will ensure the values are within the range specified by
1940 * table->extra1 (min) and table->extra2 (max).
1942 * Returns 0 on success.
1944 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
1945 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1947 struct do_proc_dointvec_minmax_conv_param param
= {
1948 .min
= (int *) table
->extra1
,
1949 .max
= (int *) table
->extra2
,
1951 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
1952 do_proc_dointvec_minmax_conv
, ¶m
);
1955 static int __do_proc_doulongvec_minmax(void *data
, ctl_table
*table
, int write
,
1957 void __user
*buffer
,
1958 size_t *lenp
, loff_t
*ppos
,
1959 unsigned long convmul
,
1960 unsigned long convdiv
)
1962 #define TMPBUFLEN 21
1963 unsigned long *i
, *min
, *max
, val
;
1964 int vleft
, first
=1, neg
;
1966 char buf
[TMPBUFLEN
], *p
;
1967 char __user
*s
= buffer
;
1969 if (!data
|| !table
->maxlen
|| !*lenp
||
1970 (*ppos
&& !write
)) {
1975 i
= (unsigned long *) data
;
1976 min
= (unsigned long *) table
->extra1
;
1977 max
= (unsigned long *) table
->extra2
;
1978 vleft
= table
->maxlen
/ sizeof(unsigned long);
1981 for (; left
&& vleft
--; i
++, min
++, max
++, first
=0) {
1996 if (len
> TMPBUFLEN
-1)
1998 if (copy_from_user(buf
, s
, len
))
2002 if (*p
== '-' && left
> 1) {
2006 if (*p
< '0' || *p
> '9')
2008 val
= simple_strtoul(p
, &p
, 0) * convmul
/ convdiv
;
2010 if ((len
< left
) && *p
&& !isspace(*p
))
2019 if ((min
&& val
< *min
) || (max
&& val
> *max
))
2026 sprintf(p
, "%lu", convdiv
* (*i
) / convmul
);
2030 if(copy_to_user(s
, buf
, len
))
2037 if (!write
&& !first
&& left
) {
2038 if(put_user('\n', s
))
2045 if (get_user(c
, s
++))
2060 static int do_proc_doulongvec_minmax(ctl_table
*table
, int write
,
2062 void __user
*buffer
,
2063 size_t *lenp
, loff_t
*ppos
,
2064 unsigned long convmul
,
2065 unsigned long convdiv
)
2067 return __do_proc_doulongvec_minmax(table
->data
, table
, write
,
2068 filp
, buffer
, lenp
, ppos
, convmul
, convdiv
);
2072 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2073 * @table: the sysctl table
2074 * @write: %TRUE if this is a write to the sysctl file
2075 * @filp: the file structure
2076 * @buffer: the user buffer
2077 * @lenp: the size of the user buffer
2078 * @ppos: file position
2080 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2081 * values from/to the user buffer, treated as an ASCII string.
2083 * This routine will ensure the values are within the range specified by
2084 * table->extra1 (min) and table->extra2 (max).
2086 * Returns 0 on success.
2088 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2089 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2091 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
, lenp
, ppos
, 1l, 1l);
2095 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2096 * @table: the sysctl table
2097 * @write: %TRUE if this is a write to the sysctl file
2098 * @filp: the file structure
2099 * @buffer: the user buffer
2100 * @lenp: the size of the user buffer
2101 * @ppos: file position
2103 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2104 * values from/to the user buffer, treated as an ASCII string. The values
2105 * are treated as milliseconds, and converted to jiffies when they are stored.
2107 * This routine will ensure the values are within the range specified by
2108 * table->extra1 (min) and table->extra2 (max).
2110 * Returns 0 on success.
2112 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2114 void __user
*buffer
,
2115 size_t *lenp
, loff_t
*ppos
)
2117 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
,
2118 lenp
, ppos
, HZ
, 1000l);
2122 static int do_proc_dointvec_jiffies_conv(int *negp
, unsigned long *lvalp
,
2124 int write
, void *data
)
2127 if (*lvalp
> LONG_MAX
/ HZ
)
2129 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2135 lval
= (unsigned long)-val
;
2138 lval
= (unsigned long)val
;
2145 static int do_proc_dointvec_userhz_jiffies_conv(int *negp
, unsigned long *lvalp
,
2147 int write
, void *data
)
2150 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2152 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2158 lval
= (unsigned long)-val
;
2161 lval
= (unsigned long)val
;
2163 *lvalp
= jiffies_to_clock_t(lval
);
2168 static int do_proc_dointvec_ms_jiffies_conv(int *negp
, unsigned long *lvalp
,
2170 int write
, void *data
)
2173 *valp
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2179 lval
= (unsigned long)-val
;
2182 lval
= (unsigned long)val
;
2184 *lvalp
= jiffies_to_msecs(lval
);
2190 * proc_dointvec_jiffies - read a vector of integers as seconds
2191 * @table: the sysctl table
2192 * @write: %TRUE if this is a write to the sysctl file
2193 * @filp: the file structure
2194 * @buffer: the user buffer
2195 * @lenp: the size of the user buffer
2196 * @ppos: file position
2198 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2199 * values from/to the user buffer, treated as an ASCII string.
2200 * The values read are assumed to be in seconds, and are converted into
2203 * Returns 0 on success.
2205 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2206 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2208 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2209 do_proc_dointvec_jiffies_conv
,NULL
);
2213 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2214 * @table: the sysctl table
2215 * @write: %TRUE if this is a write to the sysctl file
2216 * @filp: the file structure
2217 * @buffer: the user buffer
2218 * @lenp: the size of the user buffer
2219 * @ppos: pointer to the file position
2221 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2222 * values from/to the user buffer, treated as an ASCII string.
2223 * The values read are assumed to be in 1/USER_HZ seconds, and
2224 * are converted into jiffies.
2226 * Returns 0 on success.
2228 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2229 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2231 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2232 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2236 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2237 * @table: the sysctl table
2238 * @write: %TRUE if this is a write to the sysctl file
2239 * @filp: the file structure
2240 * @buffer: the user buffer
2241 * @lenp: the size of the user buffer
2242 * @ppos: file position
2243 * @ppos: the current position in the file
2245 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2246 * values from/to the user buffer, treated as an ASCII string.
2247 * The values read are assumed to be in 1/1000 seconds, and
2248 * are converted into jiffies.
2250 * Returns 0 on success.
2252 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2253 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2255 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2256 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2259 static int proc_do_cad_pid(ctl_table
*table
, int write
, struct file
*filp
,
2260 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2262 struct pid
*new_pid
;
2266 tmp
= pid_nr(cad_pid
);
2268 r
= __do_proc_dointvec(&tmp
, table
, write
, filp
, buffer
,
2269 lenp
, ppos
, NULL
, NULL
);
2273 new_pid
= find_get_pid(tmp
);
2277 put_pid(xchg(&cad_pid
, new_pid
));
2281 #else /* CONFIG_PROC_FS */
2283 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
2284 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2289 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
2290 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2295 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
2296 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2301 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2302 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2307 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2308 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2313 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2314 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2319 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2320 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2325 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2326 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2331 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2333 void __user
*buffer
,
2334 size_t *lenp
, loff_t
*ppos
)
2340 #endif /* CONFIG_PROC_FS */
2343 #ifdef CONFIG_SYSCTL_SYSCALL
2345 * General sysctl support routines
2348 /* The generic string strategy routine: */
2349 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2350 void __user
*oldval
, size_t __user
*oldlenp
,
2351 void __user
*newval
, size_t newlen
)
2353 if (!table
->data
|| !table
->maxlen
)
2356 if (oldval
&& oldlenp
) {
2358 if (get_user(bufsize
, oldlenp
))
2361 size_t len
= strlen(table
->data
), copied
;
2363 /* This shouldn't trigger for a well-formed sysctl */
2364 if (len
> table
->maxlen
)
2365 len
= table
->maxlen
;
2367 /* Copy up to a max of bufsize-1 bytes of the string */
2368 copied
= (len
>= bufsize
) ? bufsize
- 1 : len
;
2370 if (copy_to_user(oldval
, table
->data
, copied
) ||
2371 put_user(0, (char __user
*)(oldval
+ copied
)))
2373 if (put_user(len
, oldlenp
))
2377 if (newval
&& newlen
) {
2378 size_t len
= newlen
;
2379 if (len
> table
->maxlen
)
2380 len
= table
->maxlen
;
2381 if(copy_from_user(table
->data
, newval
, len
))
2383 if (len
== table
->maxlen
)
2385 ((char *) table
->data
)[len
] = 0;
2391 * This function makes sure that all of the integers in the vector
2392 * are between the minimum and maximum values given in the arrays
2393 * table->extra1 and table->extra2, respectively.
2395 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2396 void __user
*oldval
, size_t __user
*oldlenp
,
2397 void __user
*newval
, size_t newlen
)
2400 if (newval
&& newlen
) {
2401 int __user
*vec
= (int __user
*) newval
;
2402 int *min
= (int *) table
->extra1
;
2403 int *max
= (int *) table
->extra2
;
2407 if (newlen
% sizeof(int) != 0)
2410 if (!table
->extra1
&& !table
->extra2
)
2413 if (newlen
> table
->maxlen
)
2414 newlen
= table
->maxlen
;
2415 length
= newlen
/ sizeof(int);
2417 for (i
= 0; i
< length
; i
++) {
2419 if (get_user(value
, vec
+ i
))
2421 if (min
&& value
< min
[i
])
2423 if (max
&& value
> max
[i
])
2430 /* Strategy function to convert jiffies to seconds */
2431 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2432 void __user
*oldval
, size_t __user
*oldlenp
,
2433 void __user
*newval
, size_t newlen
)
2435 if (oldval
&& oldlenp
) {
2438 if (get_user(olen
, oldlenp
))
2443 if (olen
< sizeof(int))
2446 val
= *(int *)(table
->data
) / HZ
;
2447 if (put_user(val
, (int __user
*)oldval
))
2449 if (put_user(sizeof(int), oldlenp
))
2453 if (newval
&& newlen
) {
2455 if (newlen
!= sizeof(int))
2457 if (get_user(new, (int __user
*)newval
))
2459 *(int *)(table
->data
) = new*HZ
;
2464 /* Strategy function to convert jiffies to seconds */
2465 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2466 void __user
*oldval
, size_t __user
*oldlenp
,
2467 void __user
*newval
, size_t newlen
)
2469 if (oldval
&& oldlenp
) {
2472 if (get_user(olen
, oldlenp
))
2477 if (olen
< sizeof(int))
2480 val
= jiffies_to_msecs(*(int *)(table
->data
));
2481 if (put_user(val
, (int __user
*)oldval
))
2483 if (put_user(sizeof(int), oldlenp
))
2487 if (newval
&& newlen
) {
2489 if (newlen
!= sizeof(int))
2491 if (get_user(new, (int __user
*)newval
))
2493 *(int *)(table
->data
) = msecs_to_jiffies(new);
2500 #else /* CONFIG_SYSCTL_SYSCALL */
2503 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
2505 static int msg_count
;
2506 struct __sysctl_args tmp
;
2507 int name
[CTL_MAXNAME
];
2510 /* Read in the sysctl name for better debug message logging */
2511 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
2513 if (tmp
.nlen
<= 0 || tmp
.nlen
>= CTL_MAXNAME
)
2515 for (i
= 0; i
< tmp
.nlen
; i
++)
2516 if (get_user(name
[i
], tmp
.name
+ i
))
2519 /* Ignore accesses to kernel.version */
2520 if ((tmp
.nlen
== 2) && (name
[0] == CTL_KERN
) && (name
[1] == KERN_VERSION
))
2523 if (msg_count
< 5) {
2526 "warning: process `%s' used the removed sysctl "
2527 "system call with ", current
->comm
);
2528 for (i
= 0; i
< tmp
.nlen
; i
++)
2529 printk("%d.", name
[i
]);
2536 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2537 void __user
*oldval
, size_t __user
*oldlenp
,
2538 void __user
*newval
, size_t newlen
)
2543 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2544 void __user
*oldval
, size_t __user
*oldlenp
,
2545 void __user
*newval
, size_t newlen
)
2550 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2551 void __user
*oldval
, size_t __user
*oldlenp
,
2552 void __user
*newval
, size_t newlen
)
2557 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2558 void __user
*oldval
, size_t __user
*oldlenp
,
2559 void __user
*newval
, size_t newlen
)
2564 #endif /* CONFIG_SYSCTL_SYSCALL */
2567 * No sense putting this after each symbol definition, twice,
2568 * exception granted :-)
2570 EXPORT_SYMBOL(proc_dointvec
);
2571 EXPORT_SYMBOL(proc_dointvec_jiffies
);
2572 EXPORT_SYMBOL(proc_dointvec_minmax
);
2573 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
2574 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
2575 EXPORT_SYMBOL(proc_dostring
);
2576 EXPORT_SYMBOL(proc_doulongvec_minmax
);
2577 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);
2578 EXPORT_SYMBOL(register_sysctl_table
);
2579 EXPORT_SYMBOL(sysctl_intvec
);
2580 EXPORT_SYMBOL(sysctl_jiffies
);
2581 EXPORT_SYMBOL(sysctl_ms_jiffies
);
2582 EXPORT_SYMBOL(sysctl_string
);
2583 EXPORT_SYMBOL(unregister_sysctl_table
);