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/capability.h>
31 #include <linux/smp_lock.h>
33 #include <linux/init.h>
34 #include <linux/kernel.h>
35 #include <linux/kobject.h>
36 #include <linux/net.h>
37 #include <linux/sysrq.h>
38 #include <linux/highuid.h>
39 #include <linux/writeback.h>
40 #include <linux/hugetlb.h>
41 #include <linux/security.h>
42 #include <linux/initrd.h>
43 #include <linux/times.h>
44 #include <linux/limits.h>
45 #include <linux/dcache.h>
46 #include <linux/syscalls.h>
47 #include <linux/nfs_fs.h>
48 #include <linux/acpi.h>
49 #include <linux/reboot.h>
51 #include <asm/uaccess.h>
52 #include <asm/processor.h>
56 #include <asm/stacktrace.h>
59 #if defined(CONFIG_SYSCTL)
61 /* External variables not in a header file. */
63 extern int print_fatal_signals
;
64 extern int sysctl_overcommit_memory
;
65 extern int sysctl_overcommit_ratio
;
66 extern int sysctl_panic_on_oom
;
67 extern int max_threads
;
68 extern int core_uses_pid
;
69 extern int suid_dumpable
;
70 extern char core_pattern
[];
72 extern int min_free_kbytes
;
73 extern int printk_ratelimit_jiffies
;
74 extern int printk_ratelimit_burst
;
75 extern int pid_max_min
, pid_max_max
;
76 extern int sysctl_drop_caches
;
77 extern int percpu_pagelist_fraction
;
78 extern int compat_log
;
79 extern int maps_protect
;
80 extern int sysctl_stat_interval
;
81 extern int audit_argv_kb
;
83 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
84 static int maxolduid
= 65535;
86 static int min_percpu_pagelist_fract
= 8;
88 static int ngroups_max
= NGROUPS_MAX
;
91 extern char modprobe_path
[];
93 #ifdef CONFIG_CHR_DEV_SG
94 extern int sg_big_buff
;
98 extern char reboot_command
[];
99 extern int stop_a_enabled
;
100 extern int scons_pwroff
;
104 extern int pwrsw_enabled
;
105 extern int unaligned_enabled
;
109 #ifdef CONFIG_MATHEMU
110 extern int sysctl_ieee_emulation_warnings
;
112 extern int sysctl_userprocess_debug
;
113 extern int spin_retry
;
116 extern int sysctl_hz_timer
;
118 #ifdef CONFIG_BSD_PROCESS_ACCT
119 extern int acct_parm
[];
123 extern int no_unaligned_warning
;
126 #ifdef CONFIG_RT_MUTEXES
127 extern int max_lock_depth
;
130 #ifdef CONFIG_SYSCTL_SYSCALL
131 static int parse_table(int __user
*, int, void __user
*, size_t __user
*,
132 void __user
*, size_t, ctl_table
*);
136 #ifdef CONFIG_PROC_SYSCTL
137 static int proc_do_cad_pid(ctl_table
*table
, int write
, struct file
*filp
,
138 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
139 static int proc_dointvec_taint(ctl_table
*table
, int write
, struct file
*filp
,
140 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
143 static ctl_table root_table
[];
144 static struct ctl_table_header root_table_header
=
145 { root_table
, LIST_HEAD_INIT(root_table_header
.ctl_entry
) };
147 static ctl_table kern_table
[];
148 static ctl_table vm_table
[];
149 static ctl_table fs_table
[];
150 static ctl_table debug_table
[];
151 static ctl_table dev_table
[];
152 extern ctl_table random_table
[];
153 #ifdef CONFIG_UNIX98_PTYS
154 extern ctl_table pty_table
[];
156 #ifdef CONFIG_INOTIFY_USER
157 extern ctl_table inotify_table
[];
160 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
161 int sysctl_legacy_va_layout
;
165 /* The default sysctl tables: */
167 static ctl_table root_table
[] = {
169 .ctl_name
= CTL_KERN
,
170 .procname
= "kernel",
195 .ctl_name
= CTL_DEBUG
,
198 .child
= debug_table
,
207 * NOTE: do not add new entries to this table unless you have read
208 * Documentation/sysctl/ctl_unnumbered.txt
213 #ifdef CONFIG_SCHED_DEBUG
214 static unsigned long min_sched_granularity_ns
= 100000; /* 100 usecs */
215 static unsigned long max_sched_granularity_ns
= 1000000000; /* 1 second */
216 static unsigned long min_wakeup_granularity_ns
; /* 0 usecs */
217 static unsigned long max_wakeup_granularity_ns
= 1000000000; /* 1 second */
220 static ctl_table kern_table
[] = {
221 #ifdef CONFIG_SCHED_DEBUG
223 .ctl_name
= CTL_UNNUMBERED
,
224 .procname
= "sched_granularity_ns",
225 .data
= &sysctl_sched_granularity
,
226 .maxlen
= sizeof(unsigned int),
228 .proc_handler
= &proc_dointvec_minmax
,
229 .strategy
= &sysctl_intvec
,
230 .extra1
= &min_sched_granularity_ns
,
231 .extra2
= &max_sched_granularity_ns
,
234 .ctl_name
= CTL_UNNUMBERED
,
235 .procname
= "sched_wakeup_granularity_ns",
236 .data
= &sysctl_sched_wakeup_granularity
,
237 .maxlen
= sizeof(unsigned int),
239 .proc_handler
= &proc_dointvec_minmax
,
240 .strategy
= &sysctl_intvec
,
241 .extra1
= &min_wakeup_granularity_ns
,
242 .extra2
= &max_wakeup_granularity_ns
,
245 .ctl_name
= CTL_UNNUMBERED
,
246 .procname
= "sched_batch_wakeup_granularity_ns",
247 .data
= &sysctl_sched_batch_wakeup_granularity
,
248 .maxlen
= sizeof(unsigned int),
250 .proc_handler
= &proc_dointvec_minmax
,
251 .strategy
= &sysctl_intvec
,
252 .extra1
= &min_wakeup_granularity_ns
,
253 .extra2
= &max_wakeup_granularity_ns
,
256 .ctl_name
= CTL_UNNUMBERED
,
257 .procname
= "sched_stat_granularity_ns",
258 .data
= &sysctl_sched_stat_granularity
,
259 .maxlen
= sizeof(unsigned int),
261 .proc_handler
= &proc_dointvec_minmax
,
262 .strategy
= &sysctl_intvec
,
263 .extra1
= &min_wakeup_granularity_ns
,
264 .extra2
= &max_wakeup_granularity_ns
,
267 .ctl_name
= CTL_UNNUMBERED
,
268 .procname
= "sched_runtime_limit_ns",
269 .data
= &sysctl_sched_runtime_limit
,
270 .maxlen
= sizeof(unsigned int),
272 .proc_handler
= &proc_dointvec_minmax
,
273 .strategy
= &sysctl_intvec
,
274 .extra1
= &min_sched_granularity_ns
,
275 .extra2
= &max_sched_granularity_ns
,
278 .ctl_name
= CTL_UNNUMBERED
,
279 .procname
= "sched_child_runs_first",
280 .data
= &sysctl_sched_child_runs_first
,
281 .maxlen
= sizeof(unsigned int),
283 .proc_handler
= &proc_dointvec
,
286 .ctl_name
= CTL_UNNUMBERED
,
287 .procname
= "sched_features",
288 .data
= &sysctl_sched_features
,
289 .maxlen
= sizeof(unsigned int),
291 .proc_handler
= &proc_dointvec
,
295 .ctl_name
= KERN_PANIC
,
297 .data
= &panic_timeout
,
298 .maxlen
= sizeof(int),
300 .proc_handler
= &proc_dointvec
,
303 .ctl_name
= KERN_CORE_USES_PID
,
304 .procname
= "core_uses_pid",
305 .data
= &core_uses_pid
,
306 .maxlen
= sizeof(int),
308 .proc_handler
= &proc_dointvec
,
310 #ifdef CONFIG_AUDITSYSCALL
312 .ctl_name
= CTL_UNNUMBERED
,
313 .procname
= "audit_argv_kb",
314 .data
= &audit_argv_kb
,
315 .maxlen
= sizeof(int),
317 .proc_handler
= &proc_dointvec
,
321 .ctl_name
= KERN_CORE_PATTERN
,
322 .procname
= "core_pattern",
323 .data
= core_pattern
,
324 .maxlen
= CORENAME_MAX_SIZE
,
326 .proc_handler
= &proc_dostring
,
327 .strategy
= &sysctl_string
,
329 #ifdef CONFIG_PROC_SYSCTL
331 .ctl_name
= KERN_TAINTED
,
332 .procname
= "tainted",
334 .maxlen
= sizeof(int),
336 .proc_handler
= &proc_dointvec_taint
,
340 .ctl_name
= KERN_CAP_BSET
,
341 .procname
= "cap-bound",
343 .maxlen
= sizeof(kernel_cap_t
),
345 .proc_handler
= &proc_dointvec_bset
,
347 #ifdef CONFIG_BLK_DEV_INITRD
349 .ctl_name
= KERN_REALROOTDEV
,
350 .procname
= "real-root-dev",
351 .data
= &real_root_dev
,
352 .maxlen
= sizeof(int),
354 .proc_handler
= &proc_dointvec
,
358 .ctl_name
= CTL_UNNUMBERED
,
359 .procname
= "print-fatal-signals",
360 .data
= &print_fatal_signals
,
361 .maxlen
= sizeof(int),
363 .proc_handler
= &proc_dointvec
,
367 .ctl_name
= KERN_SPARC_REBOOT
,
368 .procname
= "reboot-cmd",
369 .data
= reboot_command
,
372 .proc_handler
= &proc_dostring
,
373 .strategy
= &sysctl_string
,
376 .ctl_name
= KERN_SPARC_STOP_A
,
377 .procname
= "stop-a",
378 .data
= &stop_a_enabled
,
379 .maxlen
= sizeof (int),
381 .proc_handler
= &proc_dointvec
,
384 .ctl_name
= KERN_SPARC_SCONS_PWROFF
,
385 .procname
= "scons-poweroff",
386 .data
= &scons_pwroff
,
387 .maxlen
= sizeof (int),
389 .proc_handler
= &proc_dointvec
,
394 .ctl_name
= KERN_HPPA_PWRSW
,
395 .procname
= "soft-power",
396 .data
= &pwrsw_enabled
,
397 .maxlen
= sizeof (int),
399 .proc_handler
= &proc_dointvec
,
402 .ctl_name
= KERN_HPPA_UNALIGNED
,
403 .procname
= "unaligned-trap",
404 .data
= &unaligned_enabled
,
405 .maxlen
= sizeof (int),
407 .proc_handler
= &proc_dointvec
,
411 .ctl_name
= KERN_CTLALTDEL
,
412 .procname
= "ctrl-alt-del",
414 .maxlen
= sizeof(int),
416 .proc_handler
= &proc_dointvec
,
419 .ctl_name
= KERN_PRINTK
,
420 .procname
= "printk",
421 .data
= &console_loglevel
,
422 .maxlen
= 4*sizeof(int),
424 .proc_handler
= &proc_dointvec
,
428 .ctl_name
= KERN_MODPROBE
,
429 .procname
= "modprobe",
430 .data
= &modprobe_path
,
431 .maxlen
= KMOD_PATH_LEN
,
433 .proc_handler
= &proc_dostring
,
434 .strategy
= &sysctl_string
,
437 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
439 .ctl_name
= KERN_HOTPLUG
,
440 .procname
= "hotplug",
441 .data
= &uevent_helper
,
442 .maxlen
= UEVENT_HELPER_PATH_LEN
,
444 .proc_handler
= &proc_dostring
,
445 .strategy
= &sysctl_string
,
448 #ifdef CONFIG_CHR_DEV_SG
450 .ctl_name
= KERN_SG_BIG_BUFF
,
451 .procname
= "sg-big-buff",
452 .data
= &sg_big_buff
,
453 .maxlen
= sizeof (int),
455 .proc_handler
= &proc_dointvec
,
458 #ifdef CONFIG_BSD_PROCESS_ACCT
460 .ctl_name
= KERN_ACCT
,
463 .maxlen
= 3*sizeof(int),
465 .proc_handler
= &proc_dointvec
,
468 #ifdef CONFIG_MAGIC_SYSRQ
470 .ctl_name
= KERN_SYSRQ
,
472 .data
= &__sysrq_enabled
,
473 .maxlen
= sizeof (int),
475 .proc_handler
= &proc_dointvec
,
478 #ifdef CONFIG_PROC_SYSCTL
480 .ctl_name
= KERN_CADPID
,
481 .procname
= "cad_pid",
483 .maxlen
= sizeof (int),
485 .proc_handler
= &proc_do_cad_pid
,
489 .ctl_name
= KERN_MAX_THREADS
,
490 .procname
= "threads-max",
491 .data
= &max_threads
,
492 .maxlen
= sizeof(int),
494 .proc_handler
= &proc_dointvec
,
497 .ctl_name
= KERN_RANDOM
,
498 .procname
= "random",
500 .child
= random_table
,
502 #ifdef CONFIG_UNIX98_PTYS
504 .ctl_name
= KERN_PTY
,
511 .ctl_name
= KERN_OVERFLOWUID
,
512 .procname
= "overflowuid",
513 .data
= &overflowuid
,
514 .maxlen
= sizeof(int),
516 .proc_handler
= &proc_dointvec_minmax
,
517 .strategy
= &sysctl_intvec
,
518 .extra1
= &minolduid
,
519 .extra2
= &maxolduid
,
522 .ctl_name
= KERN_OVERFLOWGID
,
523 .procname
= "overflowgid",
524 .data
= &overflowgid
,
525 .maxlen
= sizeof(int),
527 .proc_handler
= &proc_dointvec_minmax
,
528 .strategy
= &sysctl_intvec
,
529 .extra1
= &minolduid
,
530 .extra2
= &maxolduid
,
533 #ifdef CONFIG_MATHEMU
535 .ctl_name
= KERN_IEEE_EMULATION_WARNINGS
,
536 .procname
= "ieee_emulation_warnings",
537 .data
= &sysctl_ieee_emulation_warnings
,
538 .maxlen
= sizeof(int),
540 .proc_handler
= &proc_dointvec
,
543 #ifdef CONFIG_NO_IDLE_HZ
545 .ctl_name
= KERN_HZ_TIMER
,
546 .procname
= "hz_timer",
547 .data
= &sysctl_hz_timer
,
548 .maxlen
= sizeof(int),
550 .proc_handler
= &proc_dointvec
,
554 .ctl_name
= KERN_S390_USER_DEBUG_LOGGING
,
555 .procname
= "userprocess_debug",
556 .data
= &sysctl_userprocess_debug
,
557 .maxlen
= sizeof(int),
559 .proc_handler
= &proc_dointvec
,
563 .ctl_name
= KERN_PIDMAX
,
564 .procname
= "pid_max",
566 .maxlen
= sizeof (int),
568 .proc_handler
= &proc_dointvec_minmax
,
569 .strategy
= sysctl_intvec
,
570 .extra1
= &pid_max_min
,
571 .extra2
= &pid_max_max
,
574 .ctl_name
= KERN_PANIC_ON_OOPS
,
575 .procname
= "panic_on_oops",
576 .data
= &panic_on_oops
,
577 .maxlen
= sizeof(int),
579 .proc_handler
= &proc_dointvec
,
582 .ctl_name
= KERN_PRINTK_RATELIMIT
,
583 .procname
= "printk_ratelimit",
584 .data
= &printk_ratelimit_jiffies
,
585 .maxlen
= sizeof(int),
587 .proc_handler
= &proc_dointvec_jiffies
,
588 .strategy
= &sysctl_jiffies
,
591 .ctl_name
= KERN_PRINTK_RATELIMIT_BURST
,
592 .procname
= "printk_ratelimit_burst",
593 .data
= &printk_ratelimit_burst
,
594 .maxlen
= sizeof(int),
596 .proc_handler
= &proc_dointvec
,
599 .ctl_name
= KERN_NGROUPS_MAX
,
600 .procname
= "ngroups_max",
601 .data
= &ngroups_max
,
602 .maxlen
= sizeof (int),
604 .proc_handler
= &proc_dointvec
,
606 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
608 .ctl_name
= KERN_UNKNOWN_NMI_PANIC
,
609 .procname
= "unknown_nmi_panic",
610 .data
= &unknown_nmi_panic
,
611 .maxlen
= sizeof (int),
613 .proc_handler
= &proc_dointvec
,
616 .ctl_name
= KERN_NMI_WATCHDOG
,
617 .procname
= "nmi_watchdog",
618 .data
= &nmi_watchdog_enabled
,
619 .maxlen
= sizeof (int),
621 .proc_handler
= &proc_nmi_enabled
,
624 #if defined(CONFIG_X86)
626 .ctl_name
= KERN_PANIC_ON_NMI
,
627 .procname
= "panic_on_unrecovered_nmi",
628 .data
= &panic_on_unrecovered_nmi
,
629 .maxlen
= sizeof(int),
631 .proc_handler
= &proc_dointvec
,
634 .ctl_name
= KERN_BOOTLOADER_TYPE
,
635 .procname
= "bootloader_type",
636 .data
= &bootloader_type
,
637 .maxlen
= sizeof (int),
639 .proc_handler
= &proc_dointvec
,
642 .ctl_name
= CTL_UNNUMBERED
,
643 .procname
= "kstack_depth_to_print",
644 .data
= &kstack_depth_to_print
,
645 .maxlen
= sizeof(int),
647 .proc_handler
= &proc_dointvec
,
650 #if defined(CONFIG_MMU)
652 .ctl_name
= KERN_RANDOMIZE
,
653 .procname
= "randomize_va_space",
654 .data
= &randomize_va_space
,
655 .maxlen
= sizeof(int),
657 .proc_handler
= &proc_dointvec
,
660 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
662 .ctl_name
= KERN_SPIN_RETRY
,
663 .procname
= "spin_retry",
665 .maxlen
= sizeof (int),
667 .proc_handler
= &proc_dointvec
,
670 #ifdef CONFIG_ACPI_SLEEP
672 .ctl_name
= KERN_ACPI_VIDEO_FLAGS
,
673 .procname
= "acpi_video_flags",
674 .data
= &acpi_realmode_flags
,
675 .maxlen
= sizeof (unsigned long),
677 .proc_handler
= &proc_doulongvec_minmax
,
682 .ctl_name
= KERN_IA64_UNALIGNED
,
683 .procname
= "ignore-unaligned-usertrap",
684 .data
= &no_unaligned_warning
,
685 .maxlen
= sizeof (int),
687 .proc_handler
= &proc_dointvec
,
692 .ctl_name
= KERN_COMPAT_LOG
,
693 .procname
= "compat-log",
695 .maxlen
= sizeof (int),
697 .proc_handler
= &proc_dointvec
,
700 #ifdef CONFIG_RT_MUTEXES
702 .ctl_name
= KERN_MAX_LOCK_DEPTH
,
703 .procname
= "max_lock_depth",
704 .data
= &max_lock_depth
,
705 .maxlen
= sizeof(int),
707 .proc_handler
= &proc_dointvec
,
710 #ifdef CONFIG_PROC_FS
712 .ctl_name
= CTL_UNNUMBERED
,
713 .procname
= "maps_protect",
714 .data
= &maps_protect
,
715 .maxlen
= sizeof(int),
717 .proc_handler
= &proc_dointvec
,
721 .ctl_name
= CTL_UNNUMBERED
,
722 .procname
= "poweroff_cmd",
723 .data
= &poweroff_cmd
,
724 .maxlen
= POWEROFF_CMD_PATH_LEN
,
726 .proc_handler
= &proc_dostring
,
727 .strategy
= &sysctl_string
,
733 /* Constants for minimum and maximum testing in vm_table.
734 We use these as one-element integer vectors. */
737 static int one_hundred
= 100;
740 static ctl_table vm_table
[] = {
742 .ctl_name
= VM_OVERCOMMIT_MEMORY
,
743 .procname
= "overcommit_memory",
744 .data
= &sysctl_overcommit_memory
,
745 .maxlen
= sizeof(sysctl_overcommit_memory
),
747 .proc_handler
= &proc_dointvec
,
750 .ctl_name
= VM_PANIC_ON_OOM
,
751 .procname
= "panic_on_oom",
752 .data
= &sysctl_panic_on_oom
,
753 .maxlen
= sizeof(sysctl_panic_on_oom
),
755 .proc_handler
= &proc_dointvec
,
758 .ctl_name
= VM_OVERCOMMIT_RATIO
,
759 .procname
= "overcommit_ratio",
760 .data
= &sysctl_overcommit_ratio
,
761 .maxlen
= sizeof(sysctl_overcommit_ratio
),
763 .proc_handler
= &proc_dointvec
,
766 .ctl_name
= VM_PAGE_CLUSTER
,
767 .procname
= "page-cluster",
768 .data
= &page_cluster
,
769 .maxlen
= sizeof(int),
771 .proc_handler
= &proc_dointvec
,
774 .ctl_name
= VM_DIRTY_BACKGROUND
,
775 .procname
= "dirty_background_ratio",
776 .data
= &dirty_background_ratio
,
777 .maxlen
= sizeof(dirty_background_ratio
),
779 .proc_handler
= &proc_dointvec_minmax
,
780 .strategy
= &sysctl_intvec
,
782 .extra2
= &one_hundred
,
785 .ctl_name
= VM_DIRTY_RATIO
,
786 .procname
= "dirty_ratio",
787 .data
= &vm_dirty_ratio
,
788 .maxlen
= sizeof(vm_dirty_ratio
),
790 .proc_handler
= &proc_dointvec_minmax
,
791 .strategy
= &sysctl_intvec
,
793 .extra2
= &one_hundred
,
796 .ctl_name
= VM_DIRTY_WB_CS
,
797 .procname
= "dirty_writeback_centisecs",
798 .data
= &dirty_writeback_interval
,
799 .maxlen
= sizeof(dirty_writeback_interval
),
801 .proc_handler
= &dirty_writeback_centisecs_handler
,
804 .ctl_name
= VM_DIRTY_EXPIRE_CS
,
805 .procname
= "dirty_expire_centisecs",
806 .data
= &dirty_expire_interval
,
807 .maxlen
= sizeof(dirty_expire_interval
),
809 .proc_handler
= &proc_dointvec_userhz_jiffies
,
812 .ctl_name
= VM_NR_PDFLUSH_THREADS
,
813 .procname
= "nr_pdflush_threads",
814 .data
= &nr_pdflush_threads
,
815 .maxlen
= sizeof nr_pdflush_threads
,
816 .mode
= 0444 /* read-only*/,
817 .proc_handler
= &proc_dointvec
,
820 .ctl_name
= VM_SWAPPINESS
,
821 .procname
= "swappiness",
822 .data
= &vm_swappiness
,
823 .maxlen
= sizeof(vm_swappiness
),
825 .proc_handler
= &proc_dointvec_minmax
,
826 .strategy
= &sysctl_intvec
,
828 .extra2
= &one_hundred
,
830 #ifdef CONFIG_HUGETLB_PAGE
832 .ctl_name
= VM_HUGETLB_PAGES
,
833 .procname
= "nr_hugepages",
834 .data
= &max_huge_pages
,
835 .maxlen
= sizeof(unsigned long),
837 .proc_handler
= &hugetlb_sysctl_handler
,
838 .extra1
= (void *)&hugetlb_zero
,
839 .extra2
= (void *)&hugetlb_infinity
,
842 .ctl_name
= VM_HUGETLB_GROUP
,
843 .procname
= "hugetlb_shm_group",
844 .data
= &sysctl_hugetlb_shm_group
,
845 .maxlen
= sizeof(gid_t
),
847 .proc_handler
= &proc_dointvec
,
850 .ctl_name
= CTL_UNNUMBERED
,
851 .procname
= "hugepages_treat_as_movable",
852 .data
= &hugepages_treat_as_movable
,
853 .maxlen
= sizeof(int),
855 .proc_handler
= &hugetlb_treat_movable_handler
,
859 .ctl_name
= VM_LOWMEM_RESERVE_RATIO
,
860 .procname
= "lowmem_reserve_ratio",
861 .data
= &sysctl_lowmem_reserve_ratio
,
862 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
864 .proc_handler
= &lowmem_reserve_ratio_sysctl_handler
,
865 .strategy
= &sysctl_intvec
,
868 .ctl_name
= VM_DROP_PAGECACHE
,
869 .procname
= "drop_caches",
870 .data
= &sysctl_drop_caches
,
871 .maxlen
= sizeof(int),
873 .proc_handler
= drop_caches_sysctl_handler
,
874 .strategy
= &sysctl_intvec
,
877 .ctl_name
= VM_MIN_FREE_KBYTES
,
878 .procname
= "min_free_kbytes",
879 .data
= &min_free_kbytes
,
880 .maxlen
= sizeof(min_free_kbytes
),
882 .proc_handler
= &min_free_kbytes_sysctl_handler
,
883 .strategy
= &sysctl_intvec
,
887 .ctl_name
= VM_PERCPU_PAGELIST_FRACTION
,
888 .procname
= "percpu_pagelist_fraction",
889 .data
= &percpu_pagelist_fraction
,
890 .maxlen
= sizeof(percpu_pagelist_fraction
),
892 .proc_handler
= &percpu_pagelist_fraction_sysctl_handler
,
893 .strategy
= &sysctl_intvec
,
894 .extra1
= &min_percpu_pagelist_fract
,
898 .ctl_name
= VM_MAX_MAP_COUNT
,
899 .procname
= "max_map_count",
900 .data
= &sysctl_max_map_count
,
901 .maxlen
= sizeof(sysctl_max_map_count
),
903 .proc_handler
= &proc_dointvec
907 .ctl_name
= VM_LAPTOP_MODE
,
908 .procname
= "laptop_mode",
909 .data
= &laptop_mode
,
910 .maxlen
= sizeof(laptop_mode
),
912 .proc_handler
= &proc_dointvec_jiffies
,
913 .strategy
= &sysctl_jiffies
,
916 .ctl_name
= VM_BLOCK_DUMP
,
917 .procname
= "block_dump",
919 .maxlen
= sizeof(block_dump
),
921 .proc_handler
= &proc_dointvec
,
922 .strategy
= &sysctl_intvec
,
926 .ctl_name
= VM_VFS_CACHE_PRESSURE
,
927 .procname
= "vfs_cache_pressure",
928 .data
= &sysctl_vfs_cache_pressure
,
929 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
931 .proc_handler
= &proc_dointvec
,
932 .strategy
= &sysctl_intvec
,
935 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
937 .ctl_name
= VM_LEGACY_VA_LAYOUT
,
938 .procname
= "legacy_va_layout",
939 .data
= &sysctl_legacy_va_layout
,
940 .maxlen
= sizeof(sysctl_legacy_va_layout
),
942 .proc_handler
= &proc_dointvec
,
943 .strategy
= &sysctl_intvec
,
949 .ctl_name
= VM_ZONE_RECLAIM_MODE
,
950 .procname
= "zone_reclaim_mode",
951 .data
= &zone_reclaim_mode
,
952 .maxlen
= sizeof(zone_reclaim_mode
),
954 .proc_handler
= &proc_dointvec
,
955 .strategy
= &sysctl_intvec
,
959 .ctl_name
= VM_MIN_UNMAPPED
,
960 .procname
= "min_unmapped_ratio",
961 .data
= &sysctl_min_unmapped_ratio
,
962 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
964 .proc_handler
= &sysctl_min_unmapped_ratio_sysctl_handler
,
965 .strategy
= &sysctl_intvec
,
967 .extra2
= &one_hundred
,
970 .ctl_name
= VM_MIN_SLAB
,
971 .procname
= "min_slab_ratio",
972 .data
= &sysctl_min_slab_ratio
,
973 .maxlen
= sizeof(sysctl_min_slab_ratio
),
975 .proc_handler
= &sysctl_min_slab_ratio_sysctl_handler
,
976 .strategy
= &sysctl_intvec
,
978 .extra2
= &one_hundred
,
983 .ctl_name
= CTL_UNNUMBERED
,
984 .procname
= "stat_interval",
985 .data
= &sysctl_stat_interval
,
986 .maxlen
= sizeof(sysctl_stat_interval
),
988 .proc_handler
= &proc_dointvec_jiffies
,
989 .strategy
= &sysctl_jiffies
,
992 #ifdef CONFIG_SECURITY
994 .ctl_name
= CTL_UNNUMBERED
,
995 .procname
= "mmap_min_addr",
996 .data
= &mmap_min_addr
,
997 .maxlen
= sizeof(unsigned long),
999 .proc_handler
= &proc_doulongvec_minmax
,
1003 .ctl_name
= CTL_UNNUMBERED
,
1004 .procname
= "numa_zonelist_order",
1005 .data
= &numa_zonelist_order
,
1006 .maxlen
= NUMA_ZONELIST_ORDER_LEN
,
1008 .proc_handler
= &numa_zonelist_order_handler
,
1009 .strategy
= &sysctl_string
,
1013 #if defined(CONFIG_X86_32) || \
1014 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1016 .ctl_name
= VM_VDSO_ENABLED
,
1017 .procname
= "vdso_enabled",
1018 .data
= &vdso_enabled
,
1019 .maxlen
= sizeof(vdso_enabled
),
1021 .proc_handler
= &proc_dointvec
,
1022 .strategy
= &sysctl_intvec
,
1027 * NOTE: do not add new entries to this table unless you have read
1028 * Documentation/sysctl/ctl_unnumbered.txt
1033 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1034 static ctl_table binfmt_misc_table
[] = {
1039 static ctl_table fs_table
[] = {
1041 .ctl_name
= FS_NRINODE
,
1042 .procname
= "inode-nr",
1043 .data
= &inodes_stat
,
1044 .maxlen
= 2*sizeof(int),
1046 .proc_handler
= &proc_dointvec
,
1049 .ctl_name
= FS_STATINODE
,
1050 .procname
= "inode-state",
1051 .data
= &inodes_stat
,
1052 .maxlen
= 7*sizeof(int),
1054 .proc_handler
= &proc_dointvec
,
1057 .ctl_name
= FS_NRFILE
,
1058 .procname
= "file-nr",
1059 .data
= &files_stat
,
1060 .maxlen
= 3*sizeof(int),
1062 .proc_handler
= &proc_nr_files
,
1065 .ctl_name
= FS_MAXFILE
,
1066 .procname
= "file-max",
1067 .data
= &files_stat
.max_files
,
1068 .maxlen
= sizeof(int),
1070 .proc_handler
= &proc_dointvec
,
1073 .ctl_name
= FS_DENTRY
,
1074 .procname
= "dentry-state",
1075 .data
= &dentry_stat
,
1076 .maxlen
= 6*sizeof(int),
1078 .proc_handler
= &proc_dointvec
,
1081 .ctl_name
= FS_OVERFLOWUID
,
1082 .procname
= "overflowuid",
1083 .data
= &fs_overflowuid
,
1084 .maxlen
= sizeof(int),
1086 .proc_handler
= &proc_dointvec_minmax
,
1087 .strategy
= &sysctl_intvec
,
1088 .extra1
= &minolduid
,
1089 .extra2
= &maxolduid
,
1092 .ctl_name
= FS_OVERFLOWGID
,
1093 .procname
= "overflowgid",
1094 .data
= &fs_overflowgid
,
1095 .maxlen
= sizeof(int),
1097 .proc_handler
= &proc_dointvec_minmax
,
1098 .strategy
= &sysctl_intvec
,
1099 .extra1
= &minolduid
,
1100 .extra2
= &maxolduid
,
1103 .ctl_name
= FS_LEASES
,
1104 .procname
= "leases-enable",
1105 .data
= &leases_enable
,
1106 .maxlen
= sizeof(int),
1108 .proc_handler
= &proc_dointvec
,
1110 #ifdef CONFIG_DNOTIFY
1112 .ctl_name
= FS_DIR_NOTIFY
,
1113 .procname
= "dir-notify-enable",
1114 .data
= &dir_notify_enable
,
1115 .maxlen
= sizeof(int),
1117 .proc_handler
= &proc_dointvec
,
1122 .ctl_name
= FS_LEASE_TIME
,
1123 .procname
= "lease-break-time",
1124 .data
= &lease_break_time
,
1125 .maxlen
= sizeof(int),
1127 .proc_handler
= &proc_dointvec_minmax
,
1128 .strategy
= &sysctl_intvec
,
1133 .ctl_name
= FS_AIO_NR
,
1134 .procname
= "aio-nr",
1136 .maxlen
= sizeof(aio_nr
),
1138 .proc_handler
= &proc_doulongvec_minmax
,
1141 .ctl_name
= FS_AIO_MAX_NR
,
1142 .procname
= "aio-max-nr",
1143 .data
= &aio_max_nr
,
1144 .maxlen
= sizeof(aio_max_nr
),
1146 .proc_handler
= &proc_doulongvec_minmax
,
1148 #ifdef CONFIG_INOTIFY_USER
1150 .ctl_name
= FS_INOTIFY
,
1151 .procname
= "inotify",
1153 .child
= inotify_table
,
1158 .ctl_name
= KERN_SETUID_DUMPABLE
,
1159 .procname
= "suid_dumpable",
1160 .data
= &suid_dumpable
,
1161 .maxlen
= sizeof(int),
1163 .proc_handler
= &proc_dointvec
,
1165 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1167 .ctl_name
= CTL_UNNUMBERED
,
1168 .procname
= "binfmt_misc",
1170 .child
= binfmt_misc_table
,
1174 * NOTE: do not add new entries to this table unless you have read
1175 * Documentation/sysctl/ctl_unnumbered.txt
1180 static ctl_table debug_table
[] = {
1184 static ctl_table dev_table
[] = {
1188 static DEFINE_SPINLOCK(sysctl_lock
);
1190 /* called under sysctl_lock */
1191 static int use_table(struct ctl_table_header
*p
)
1193 if (unlikely(p
->unregistering
))
1199 /* called under sysctl_lock */
1200 static void unuse_table(struct ctl_table_header
*p
)
1203 if (unlikely(p
->unregistering
))
1204 complete(p
->unregistering
);
1207 /* called under sysctl_lock, will reacquire if has to wait */
1208 static void start_unregistering(struct ctl_table_header
*p
)
1211 * if p->used is 0, nobody will ever touch that entry again;
1212 * we'll eliminate all paths to it before dropping sysctl_lock
1214 if (unlikely(p
->used
)) {
1215 struct completion wait
;
1216 init_completion(&wait
);
1217 p
->unregistering
= &wait
;
1218 spin_unlock(&sysctl_lock
);
1219 wait_for_completion(&wait
);
1220 spin_lock(&sysctl_lock
);
1223 * do not remove from the list until nobody holds it; walking the
1224 * list in do_sysctl() relies on that.
1226 list_del_init(&p
->ctl_entry
);
1229 void sysctl_head_finish(struct ctl_table_header
*head
)
1233 spin_lock(&sysctl_lock
);
1235 spin_unlock(&sysctl_lock
);
1238 struct ctl_table_header
*sysctl_head_next(struct ctl_table_header
*prev
)
1240 struct ctl_table_header
*head
;
1241 struct list_head
*tmp
;
1242 spin_lock(&sysctl_lock
);
1244 tmp
= &prev
->ctl_entry
;
1248 tmp
= &root_table_header
.ctl_entry
;
1250 head
= list_entry(tmp
, struct ctl_table_header
, ctl_entry
);
1252 if (!use_table(head
))
1254 spin_unlock(&sysctl_lock
);
1258 if (tmp
== &root_table_header
.ctl_entry
)
1261 spin_unlock(&sysctl_lock
);
1265 #ifdef CONFIG_SYSCTL_SYSCALL
1266 int do_sysctl(int __user
*name
, int nlen
, void __user
*oldval
, size_t __user
*oldlenp
,
1267 void __user
*newval
, size_t newlen
)
1269 struct ctl_table_header
*head
;
1270 int error
= -ENOTDIR
;
1272 if (nlen
<= 0 || nlen
>= CTL_MAXNAME
)
1276 if (!oldlenp
|| get_user(old_len
, oldlenp
))
1280 for (head
= sysctl_head_next(NULL
); head
;
1281 head
= sysctl_head_next(head
)) {
1282 error
= parse_table(name
, nlen
, oldval
, oldlenp
,
1283 newval
, newlen
, head
->ctl_table
);
1284 if (error
!= -ENOTDIR
) {
1285 sysctl_head_finish(head
);
1292 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
1294 struct __sysctl_args tmp
;
1297 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
1301 error
= do_sysctl(tmp
.name
, tmp
.nlen
, tmp
.oldval
, tmp
.oldlenp
,
1302 tmp
.newval
, tmp
.newlen
);
1306 #endif /* CONFIG_SYSCTL_SYSCALL */
1309 * sysctl_perm does NOT grant the superuser all rights automatically, because
1310 * some sysctl variables are readonly even to root.
1313 static int test_perm(int mode
, int op
)
1317 else if (in_egroup_p(0))
1319 if ((mode
& op
& 0007) == op
)
1324 int sysctl_perm(ctl_table
*table
, int op
)
1327 error
= security_sysctl(table
, op
);
1330 return test_perm(table
->mode
, op
);
1333 #ifdef CONFIG_SYSCTL_SYSCALL
1334 static int parse_table(int __user
*name
, int nlen
,
1335 void __user
*oldval
, size_t __user
*oldlenp
,
1336 void __user
*newval
, size_t newlen
,
1343 if (get_user(n
, name
))
1345 for ( ; table
->ctl_name
|| table
->procname
; table
++) {
1346 if (!table
->ctl_name
)
1348 if (n
== table
->ctl_name
) {
1351 if (sysctl_perm(table
, 001))
1355 table
= table
->child
;
1358 error
= do_sysctl_strategy(table
, name
, nlen
,
1367 /* Perform the actual read/write of a sysctl table entry. */
1368 int do_sysctl_strategy (ctl_table
*table
,
1369 int __user
*name
, int nlen
,
1370 void __user
*oldval
, size_t __user
*oldlenp
,
1371 void __user
*newval
, size_t newlen
)
1380 if (sysctl_perm(table
, op
))
1383 if (table
->strategy
) {
1384 rc
= table
->strategy(table
, name
, nlen
, oldval
, oldlenp
,
1392 /* If there is no strategy routine, or if the strategy returns
1393 * zero, proceed with automatic r/w */
1394 if (table
->data
&& table
->maxlen
) {
1395 if (oldval
&& oldlenp
) {
1396 if (get_user(len
, oldlenp
))
1399 if (len
> table
->maxlen
)
1400 len
= table
->maxlen
;
1401 if(copy_to_user(oldval
, table
->data
, len
))
1403 if(put_user(len
, oldlenp
))
1407 if (newval
&& newlen
) {
1409 if (len
> table
->maxlen
)
1410 len
= table
->maxlen
;
1411 if(copy_from_user(table
->data
, newval
, len
))
1417 #endif /* CONFIG_SYSCTL_SYSCALL */
1419 static void sysctl_set_parent(struct ctl_table
*parent
, struct ctl_table
*table
)
1421 for (; table
->ctl_name
|| table
->procname
; table
++) {
1422 table
->parent
= parent
;
1424 sysctl_set_parent(table
, table
->child
);
1428 static __init
int sysctl_init(void)
1430 sysctl_set_parent(NULL
, root_table
);
1434 core_initcall(sysctl_init
);
1437 * register_sysctl_table - register a sysctl hierarchy
1438 * @table: the top-level table structure
1440 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1441 * array. An entry with a ctl_name of 0 terminates the table.
1443 * The members of the &ctl_table structure are used as follows:
1445 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1446 * must be unique within that level of sysctl
1448 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1449 * enter a sysctl file
1451 * data - a pointer to data for use by proc_handler
1453 * maxlen - the maximum size in bytes of the data
1455 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1457 * child - a pointer to the child sysctl table if this entry is a directory, or
1460 * proc_handler - the text handler routine (described below)
1462 * strategy - the strategy routine (described below)
1464 * de - for internal use by the sysctl routines
1466 * extra1, extra2 - extra pointers usable by the proc handler routines
1468 * Leaf nodes in the sysctl tree will be represented by a single file
1469 * under /proc; non-leaf nodes will be represented by directories.
1471 * sysctl(2) can automatically manage read and write requests through
1472 * the sysctl table. The data and maxlen fields of the ctl_table
1473 * struct enable minimal validation of the values being written to be
1474 * performed, and the mode field allows minimal authentication.
1476 * More sophisticated management can be enabled by the provision of a
1477 * strategy routine with the table entry. This will be called before
1478 * any automatic read or write of the data is performed.
1480 * The strategy routine may return
1482 * < 0 - Error occurred (error is passed to user process)
1484 * 0 - OK - proceed with automatic read or write.
1486 * > 0 - OK - read or write has been done by the strategy routine, so
1487 * return immediately.
1489 * There must be a proc_handler routine for any terminal nodes
1490 * mirrored under /proc/sys (non-terminals are handled by a built-in
1491 * directory handler). Several default handlers are available to
1492 * cover common cases -
1494 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1495 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1496 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1498 * It is the handler's job to read the input buffer from user memory
1499 * and process it. The handler should return 0 on success.
1501 * This routine returns %NULL on a failure to register, and a pointer
1502 * to the table header on success.
1504 struct ctl_table_header
*register_sysctl_table(ctl_table
* table
)
1506 struct ctl_table_header
*tmp
;
1507 tmp
= kmalloc(sizeof(struct ctl_table_header
), GFP_KERNEL
);
1510 tmp
->ctl_table
= table
;
1511 INIT_LIST_HEAD(&tmp
->ctl_entry
);
1513 tmp
->unregistering
= NULL
;
1514 sysctl_set_parent(NULL
, table
);
1515 spin_lock(&sysctl_lock
);
1516 list_add_tail(&tmp
->ctl_entry
, &root_table_header
.ctl_entry
);
1517 spin_unlock(&sysctl_lock
);
1522 * unregister_sysctl_table - unregister a sysctl table hierarchy
1523 * @header: the header returned from register_sysctl_table
1525 * Unregisters the sysctl table and all children. proc entries may not
1526 * actually be removed until they are no longer used by anyone.
1528 void unregister_sysctl_table(struct ctl_table_header
* header
)
1531 spin_lock(&sysctl_lock
);
1532 start_unregistering(header
);
1533 spin_unlock(&sysctl_lock
);
1537 #else /* !CONFIG_SYSCTL */
1538 struct ctl_table_header
*register_sysctl_table(ctl_table
* table
)
1543 void unregister_sysctl_table(struct ctl_table_header
* table
)
1547 #endif /* CONFIG_SYSCTL */
1553 #ifdef CONFIG_PROC_SYSCTL
1555 static int _proc_do_string(void* data
, int maxlen
, int write
,
1556 struct file
*filp
, void __user
*buffer
,
1557 size_t *lenp
, loff_t
*ppos
)
1563 if (!data
|| !maxlen
|| !*lenp
) {
1571 while (len
< *lenp
) {
1572 if (get_user(c
, p
++))
1574 if (c
== 0 || c
== '\n')
1580 if(copy_from_user(data
, buffer
, len
))
1582 ((char *) data
)[len
] = 0;
1600 if(copy_to_user(buffer
, data
, len
))
1603 if(put_user('\n', ((char __user
*) buffer
) + len
))
1614 * proc_dostring - read a string sysctl
1615 * @table: the sysctl table
1616 * @write: %TRUE if this is a write to the sysctl file
1617 * @filp: the file structure
1618 * @buffer: the user buffer
1619 * @lenp: the size of the user buffer
1620 * @ppos: file position
1622 * Reads/writes a string from/to the user buffer. If the kernel
1623 * buffer provided is not large enough to hold the string, the
1624 * string is truncated. The copied string is %NULL-terminated.
1625 * If the string is being read by the user process, it is copied
1626 * and a newline '\n' is added. It is truncated if the buffer is
1629 * Returns 0 on success.
1631 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
1632 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1634 return _proc_do_string(table
->data
, table
->maxlen
, write
, filp
,
1635 buffer
, lenp
, ppos
);
1639 static int do_proc_dointvec_conv(int *negp
, unsigned long *lvalp
,
1641 int write
, void *data
)
1644 *valp
= *negp
? -*lvalp
: *lvalp
;
1649 *lvalp
= (unsigned long)-val
;
1652 *lvalp
= (unsigned long)val
;
1658 static int __do_proc_dointvec(void *tbl_data
, ctl_table
*table
,
1659 int write
, struct file
*filp
, void __user
*buffer
,
1660 size_t *lenp
, loff_t
*ppos
,
1661 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1662 int write
, void *data
),
1665 #define TMPBUFLEN 21
1666 int *i
, vleft
, first
=1, neg
, val
;
1670 char buf
[TMPBUFLEN
], *p
;
1671 char __user
*s
= buffer
;
1673 if (!tbl_data
|| !table
->maxlen
|| !*lenp
||
1674 (*ppos
&& !write
)) {
1679 i
= (int *) tbl_data
;
1680 vleft
= table
->maxlen
/ sizeof(*i
);
1684 conv
= do_proc_dointvec_conv
;
1686 for (; left
&& vleft
--; i
++, first
=0) {
1701 if (len
> sizeof(buf
) - 1)
1702 len
= sizeof(buf
) - 1;
1703 if (copy_from_user(buf
, s
, len
))
1707 if (*p
== '-' && left
> 1) {
1711 if (*p
< '0' || *p
> '9')
1714 lval
= simple_strtoul(p
, &p
, 0);
1717 if ((len
< left
) && *p
&& !isspace(*p
))
1724 if (conv(&neg
, &lval
, i
, 1, data
))
1731 if (conv(&neg
, &lval
, i
, 0, data
))
1734 sprintf(p
, "%s%lu", neg
? "-" : "", lval
);
1738 if(copy_to_user(s
, buf
, len
))
1745 if (!write
&& !first
&& left
) {
1746 if(put_user('\n', s
))
1753 if (get_user(c
, s
++))
1768 static int do_proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1769 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
1770 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1771 int write
, void *data
),
1774 return __do_proc_dointvec(table
->data
, table
, write
, filp
,
1775 buffer
, lenp
, ppos
, conv
, data
);
1779 * proc_dointvec - read a vector of integers
1780 * @table: the sysctl table
1781 * @write: %TRUE if this is a write to the sysctl file
1782 * @filp: the file structure
1783 * @buffer: the user buffer
1784 * @lenp: the size of the user buffer
1785 * @ppos: file position
1787 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1788 * values from/to the user buffer, treated as an ASCII string.
1790 * Returns 0 on success.
1792 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1793 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1795 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1803 static int do_proc_dointvec_bset_conv(int *negp
, unsigned long *lvalp
,
1805 int write
, void *data
)
1807 int op
= *(int *)data
;
1809 int val
= *negp
? -*lvalp
: *lvalp
;
1811 case OP_SET
: *valp
= val
; break;
1812 case OP_AND
: *valp
&= val
; break;
1813 case OP_OR
: *valp
|= val
; break;
1819 *lvalp
= (unsigned long)-val
;
1822 *lvalp
= (unsigned long)val
;
1829 * init may raise the set.
1832 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
1833 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1837 if (write
&& !capable(CAP_SYS_MODULE
)) {
1841 op
= is_init(current
) ? OP_SET
: OP_AND
;
1842 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1843 do_proc_dointvec_bset_conv
,&op
);
1847 * Taint values can only be increased
1849 static int proc_dointvec_taint(ctl_table
*table
, int write
, struct file
*filp
,
1850 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1854 if (write
&& !capable(CAP_SYS_ADMIN
))
1858 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1859 do_proc_dointvec_bset_conv
,&op
);
1862 struct do_proc_dointvec_minmax_conv_param
{
1867 static int do_proc_dointvec_minmax_conv(int *negp
, unsigned long *lvalp
,
1869 int write
, void *data
)
1871 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
1873 int val
= *negp
? -*lvalp
: *lvalp
;
1874 if ((param
->min
&& *param
->min
> val
) ||
1875 (param
->max
&& *param
->max
< val
))
1882 *lvalp
= (unsigned long)-val
;
1885 *lvalp
= (unsigned long)val
;
1892 * proc_dointvec_minmax - read a vector of integers with min/max values
1893 * @table: the sysctl table
1894 * @write: %TRUE if this is a write to the sysctl file
1895 * @filp: the file structure
1896 * @buffer: the user buffer
1897 * @lenp: the size of the user buffer
1898 * @ppos: file position
1900 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1901 * values from/to the user buffer, treated as an ASCII string.
1903 * This routine will ensure the values are within the range specified by
1904 * table->extra1 (min) and table->extra2 (max).
1906 * Returns 0 on success.
1908 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
1909 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1911 struct do_proc_dointvec_minmax_conv_param param
= {
1912 .min
= (int *) table
->extra1
,
1913 .max
= (int *) table
->extra2
,
1915 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
1916 do_proc_dointvec_minmax_conv
, ¶m
);
1919 static int __do_proc_doulongvec_minmax(void *data
, ctl_table
*table
, int write
,
1921 void __user
*buffer
,
1922 size_t *lenp
, loff_t
*ppos
,
1923 unsigned long convmul
,
1924 unsigned long convdiv
)
1926 #define TMPBUFLEN 21
1927 unsigned long *i
, *min
, *max
, val
;
1928 int vleft
, first
=1, neg
;
1930 char buf
[TMPBUFLEN
], *p
;
1931 char __user
*s
= buffer
;
1933 if (!data
|| !table
->maxlen
|| !*lenp
||
1934 (*ppos
&& !write
)) {
1939 i
= (unsigned long *) data
;
1940 min
= (unsigned long *) table
->extra1
;
1941 max
= (unsigned long *) table
->extra2
;
1942 vleft
= table
->maxlen
/ sizeof(unsigned long);
1945 for (; left
&& vleft
--; i
++, min
++, max
++, first
=0) {
1960 if (len
> TMPBUFLEN
-1)
1962 if (copy_from_user(buf
, s
, len
))
1966 if (*p
== '-' && left
> 1) {
1970 if (*p
< '0' || *p
> '9')
1972 val
= simple_strtoul(p
, &p
, 0) * convmul
/ convdiv
;
1974 if ((len
< left
) && *p
&& !isspace(*p
))
1983 if ((min
&& val
< *min
) || (max
&& val
> *max
))
1990 sprintf(p
, "%lu", convdiv
* (*i
) / convmul
);
1994 if(copy_to_user(s
, buf
, len
))
2001 if (!write
&& !first
&& left
) {
2002 if(put_user('\n', s
))
2009 if (get_user(c
, s
++))
2024 static int do_proc_doulongvec_minmax(ctl_table
*table
, int write
,
2026 void __user
*buffer
,
2027 size_t *lenp
, loff_t
*ppos
,
2028 unsigned long convmul
,
2029 unsigned long convdiv
)
2031 return __do_proc_doulongvec_minmax(table
->data
, table
, write
,
2032 filp
, buffer
, lenp
, ppos
, convmul
, convdiv
);
2036 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2037 * @table: the sysctl table
2038 * @write: %TRUE if this is a write to the sysctl file
2039 * @filp: the file structure
2040 * @buffer: the user buffer
2041 * @lenp: the size of the user buffer
2042 * @ppos: file position
2044 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2045 * values from/to the user buffer, treated as an ASCII string.
2047 * This routine will ensure the values are within the range specified by
2048 * table->extra1 (min) and table->extra2 (max).
2050 * Returns 0 on success.
2052 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2053 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2055 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
, lenp
, ppos
, 1l, 1l);
2059 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2060 * @table: the sysctl table
2061 * @write: %TRUE if this is a write to the sysctl file
2062 * @filp: the file structure
2063 * @buffer: the user buffer
2064 * @lenp: the size of the user buffer
2065 * @ppos: file position
2067 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2068 * values from/to the user buffer, treated as an ASCII string. The values
2069 * are treated as milliseconds, and converted to jiffies when they are stored.
2071 * This routine will ensure the values are within the range specified by
2072 * table->extra1 (min) and table->extra2 (max).
2074 * Returns 0 on success.
2076 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2078 void __user
*buffer
,
2079 size_t *lenp
, loff_t
*ppos
)
2081 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
,
2082 lenp
, ppos
, HZ
, 1000l);
2086 static int do_proc_dointvec_jiffies_conv(int *negp
, unsigned long *lvalp
,
2088 int write
, void *data
)
2091 if (*lvalp
> LONG_MAX
/ HZ
)
2093 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2099 lval
= (unsigned long)-val
;
2102 lval
= (unsigned long)val
;
2109 static int do_proc_dointvec_userhz_jiffies_conv(int *negp
, unsigned long *lvalp
,
2111 int write
, void *data
)
2114 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2116 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2122 lval
= (unsigned long)-val
;
2125 lval
= (unsigned long)val
;
2127 *lvalp
= jiffies_to_clock_t(lval
);
2132 static int do_proc_dointvec_ms_jiffies_conv(int *negp
, unsigned long *lvalp
,
2134 int write
, void *data
)
2137 *valp
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2143 lval
= (unsigned long)-val
;
2146 lval
= (unsigned long)val
;
2148 *lvalp
= jiffies_to_msecs(lval
);
2154 * proc_dointvec_jiffies - read a vector of integers as seconds
2155 * @table: the sysctl table
2156 * @write: %TRUE if this is a write to the sysctl file
2157 * @filp: the file structure
2158 * @buffer: the user buffer
2159 * @lenp: the size of the user buffer
2160 * @ppos: file position
2162 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2163 * values from/to the user buffer, treated as an ASCII string.
2164 * The values read are assumed to be in seconds, and are converted into
2167 * Returns 0 on success.
2169 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2170 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2172 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2173 do_proc_dointvec_jiffies_conv
,NULL
);
2177 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2178 * @table: the sysctl table
2179 * @write: %TRUE if this is a write to the sysctl file
2180 * @filp: the file structure
2181 * @buffer: the user buffer
2182 * @lenp: the size of the user buffer
2183 * @ppos: pointer to the file position
2185 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2186 * values from/to the user buffer, treated as an ASCII string.
2187 * The values read are assumed to be in 1/USER_HZ seconds, and
2188 * are converted into jiffies.
2190 * Returns 0 on success.
2192 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2193 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2195 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2196 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2200 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2201 * @table: the sysctl table
2202 * @write: %TRUE if this is a write to the sysctl file
2203 * @filp: the file structure
2204 * @buffer: the user buffer
2205 * @lenp: the size of the user buffer
2206 * @ppos: file position
2207 * @ppos: the current position in the file
2209 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2210 * values from/to the user buffer, treated as an ASCII string.
2211 * The values read are assumed to be in 1/1000 seconds, and
2212 * are converted into jiffies.
2214 * Returns 0 on success.
2216 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2217 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2219 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2220 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2223 static int proc_do_cad_pid(ctl_table
*table
, int write
, struct file
*filp
,
2224 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2226 struct pid
*new_pid
;
2230 tmp
= pid_nr(cad_pid
);
2232 r
= __do_proc_dointvec(&tmp
, table
, write
, filp
, buffer
,
2233 lenp
, ppos
, NULL
, NULL
);
2237 new_pid
= find_get_pid(tmp
);
2241 put_pid(xchg(&cad_pid
, new_pid
));
2245 #else /* CONFIG_PROC_FS */
2247 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
2248 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2253 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
2254 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2259 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
2260 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2265 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2266 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2271 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2272 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2277 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2278 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2283 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2284 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2289 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2290 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2295 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2297 void __user
*buffer
,
2298 size_t *lenp
, loff_t
*ppos
)
2304 #endif /* CONFIG_PROC_FS */
2307 #ifdef CONFIG_SYSCTL_SYSCALL
2309 * General sysctl support routines
2312 /* The generic string strategy routine: */
2313 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2314 void __user
*oldval
, size_t __user
*oldlenp
,
2315 void __user
*newval
, size_t newlen
)
2317 if (!table
->data
|| !table
->maxlen
)
2320 if (oldval
&& oldlenp
) {
2322 if (get_user(bufsize
, oldlenp
))
2325 size_t len
= strlen(table
->data
), copied
;
2327 /* This shouldn't trigger for a well-formed sysctl */
2328 if (len
> table
->maxlen
)
2329 len
= table
->maxlen
;
2331 /* Copy up to a max of bufsize-1 bytes of the string */
2332 copied
= (len
>= bufsize
) ? bufsize
- 1 : len
;
2334 if (copy_to_user(oldval
, table
->data
, copied
) ||
2335 put_user(0, (char __user
*)(oldval
+ copied
)))
2337 if (put_user(len
, oldlenp
))
2341 if (newval
&& newlen
) {
2342 size_t len
= newlen
;
2343 if (len
> table
->maxlen
)
2344 len
= table
->maxlen
;
2345 if(copy_from_user(table
->data
, newval
, len
))
2347 if (len
== table
->maxlen
)
2349 ((char *) table
->data
)[len
] = 0;
2355 * This function makes sure that all of the integers in the vector
2356 * are between the minimum and maximum values given in the arrays
2357 * table->extra1 and table->extra2, respectively.
2359 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2360 void __user
*oldval
, size_t __user
*oldlenp
,
2361 void __user
*newval
, size_t newlen
)
2364 if (newval
&& newlen
) {
2365 int __user
*vec
= (int __user
*) newval
;
2366 int *min
= (int *) table
->extra1
;
2367 int *max
= (int *) table
->extra2
;
2371 if (newlen
% sizeof(int) != 0)
2374 if (!table
->extra1
&& !table
->extra2
)
2377 if (newlen
> table
->maxlen
)
2378 newlen
= table
->maxlen
;
2379 length
= newlen
/ sizeof(int);
2381 for (i
= 0; i
< length
; i
++) {
2383 if (get_user(value
, vec
+ i
))
2385 if (min
&& value
< min
[i
])
2387 if (max
&& value
> max
[i
])
2394 /* Strategy function to convert jiffies to seconds */
2395 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2396 void __user
*oldval
, size_t __user
*oldlenp
,
2397 void __user
*newval
, size_t newlen
)
2399 if (oldval
&& oldlenp
) {
2402 if (get_user(olen
, oldlenp
))
2407 if (olen
< sizeof(int))
2410 val
= *(int *)(table
->data
) / HZ
;
2411 if (put_user(val
, (int __user
*)oldval
))
2413 if (put_user(sizeof(int), oldlenp
))
2417 if (newval
&& newlen
) {
2419 if (newlen
!= sizeof(int))
2421 if (get_user(new, (int __user
*)newval
))
2423 *(int *)(table
->data
) = new*HZ
;
2428 /* Strategy function to convert jiffies to seconds */
2429 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2430 void __user
*oldval
, size_t __user
*oldlenp
,
2431 void __user
*newval
, size_t newlen
)
2433 if (oldval
&& oldlenp
) {
2436 if (get_user(olen
, oldlenp
))
2441 if (olen
< sizeof(int))
2444 val
= jiffies_to_msecs(*(int *)(table
->data
));
2445 if (put_user(val
, (int __user
*)oldval
))
2447 if (put_user(sizeof(int), oldlenp
))
2451 if (newval
&& newlen
) {
2453 if (newlen
!= sizeof(int))
2455 if (get_user(new, (int __user
*)newval
))
2457 *(int *)(table
->data
) = msecs_to_jiffies(new);
2464 #else /* CONFIG_SYSCTL_SYSCALL */
2467 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
2469 static int msg_count
;
2470 struct __sysctl_args tmp
;
2471 int name
[CTL_MAXNAME
];
2474 /* Read in the sysctl name for better debug message logging */
2475 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
2477 if (tmp
.nlen
<= 0 || tmp
.nlen
>= CTL_MAXNAME
)
2479 for (i
= 0; i
< tmp
.nlen
; i
++)
2480 if (get_user(name
[i
], tmp
.name
+ i
))
2483 /* Ignore accesses to kernel.version */
2484 if ((tmp
.nlen
== 2) && (name
[0] == CTL_KERN
) && (name
[1] == KERN_VERSION
))
2487 if (msg_count
< 5) {
2490 "warning: process `%s' used the removed sysctl "
2491 "system call with ", current
->comm
);
2492 for (i
= 0; i
< tmp
.nlen
; i
++)
2493 printk("%d.", name
[i
]);
2500 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2501 void __user
*oldval
, size_t __user
*oldlenp
,
2502 void __user
*newval
, size_t newlen
)
2507 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2508 void __user
*oldval
, size_t __user
*oldlenp
,
2509 void __user
*newval
, size_t newlen
)
2514 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2515 void __user
*oldval
, size_t __user
*oldlenp
,
2516 void __user
*newval
, size_t newlen
)
2521 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2522 void __user
*oldval
, size_t __user
*oldlenp
,
2523 void __user
*newval
, size_t newlen
)
2528 #endif /* CONFIG_SYSCTL_SYSCALL */
2531 * No sense putting this after each symbol definition, twice,
2532 * exception granted :-)
2534 EXPORT_SYMBOL(proc_dointvec
);
2535 EXPORT_SYMBOL(proc_dointvec_jiffies
);
2536 EXPORT_SYMBOL(proc_dointvec_minmax
);
2537 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
2538 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
2539 EXPORT_SYMBOL(proc_dostring
);
2540 EXPORT_SYMBOL(proc_doulongvec_minmax
);
2541 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);
2542 EXPORT_SYMBOL(register_sysctl_table
);
2543 EXPORT_SYMBOL(sysctl_intvec
);
2544 EXPORT_SYMBOL(sysctl_jiffies
);
2545 EXPORT_SYMBOL(sysctl_ms_jiffies
);
2546 EXPORT_SYMBOL(sysctl_string
);
2547 EXPORT_SYMBOL(unregister_sysctl_table
);