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
;
164 extern int prove_locking
;
165 extern int lock_stat
;
167 /* The default sysctl tables: */
169 static ctl_table root_table
[] = {
171 .ctl_name
= CTL_KERN
,
172 .procname
= "kernel",
197 .ctl_name
= CTL_DEBUG
,
200 .child
= debug_table
,
209 * NOTE: do not add new entries to this table unless you have read
210 * Documentation/sysctl/ctl_unnumbered.txt
215 #ifdef CONFIG_SCHED_DEBUG
216 static unsigned long min_sched_granularity_ns
= 100000; /* 100 usecs */
217 static unsigned long max_sched_granularity_ns
= 1000000000; /* 1 second */
218 static unsigned long min_wakeup_granularity_ns
; /* 0 usecs */
219 static unsigned long max_wakeup_granularity_ns
= 1000000000; /* 1 second */
222 static ctl_table kern_table
[] = {
223 #ifdef CONFIG_SCHED_DEBUG
225 .ctl_name
= CTL_UNNUMBERED
,
226 .procname
= "sched_granularity_ns",
227 .data
= &sysctl_sched_granularity
,
228 .maxlen
= sizeof(unsigned int),
230 .proc_handler
= &proc_dointvec_minmax
,
231 .strategy
= &sysctl_intvec
,
232 .extra1
= &min_sched_granularity_ns
,
233 .extra2
= &max_sched_granularity_ns
,
236 .ctl_name
= CTL_UNNUMBERED
,
237 .procname
= "sched_wakeup_granularity_ns",
238 .data
= &sysctl_sched_wakeup_granularity
,
239 .maxlen
= sizeof(unsigned int),
241 .proc_handler
= &proc_dointvec_minmax
,
242 .strategy
= &sysctl_intvec
,
243 .extra1
= &min_wakeup_granularity_ns
,
244 .extra2
= &max_wakeup_granularity_ns
,
247 .ctl_name
= CTL_UNNUMBERED
,
248 .procname
= "sched_batch_wakeup_granularity_ns",
249 .data
= &sysctl_sched_batch_wakeup_granularity
,
250 .maxlen
= sizeof(unsigned int),
252 .proc_handler
= &proc_dointvec_minmax
,
253 .strategy
= &sysctl_intvec
,
254 .extra1
= &min_wakeup_granularity_ns
,
255 .extra2
= &max_wakeup_granularity_ns
,
258 .ctl_name
= CTL_UNNUMBERED
,
259 .procname
= "sched_stat_granularity_ns",
260 .data
= &sysctl_sched_stat_granularity
,
261 .maxlen
= sizeof(unsigned int),
263 .proc_handler
= &proc_dointvec_minmax
,
264 .strategy
= &sysctl_intvec
,
265 .extra1
= &min_wakeup_granularity_ns
,
266 .extra2
= &max_wakeup_granularity_ns
,
269 .ctl_name
= CTL_UNNUMBERED
,
270 .procname
= "sched_runtime_limit_ns",
271 .data
= &sysctl_sched_runtime_limit
,
272 .maxlen
= sizeof(unsigned int),
274 .proc_handler
= &proc_dointvec_minmax
,
275 .strategy
= &sysctl_intvec
,
276 .extra1
= &min_sched_granularity_ns
,
277 .extra2
= &max_sched_granularity_ns
,
280 .ctl_name
= CTL_UNNUMBERED
,
281 .procname
= "sched_child_runs_first",
282 .data
= &sysctl_sched_child_runs_first
,
283 .maxlen
= sizeof(unsigned int),
285 .proc_handler
= &proc_dointvec
,
287 #ifdef CONFIG_PROVE_LOCKING
289 .ctl_name
= CTL_UNNUMBERED
,
290 .procname
= "prove_locking",
291 .data
= &prove_locking
,
292 .maxlen
= sizeof(int),
294 .proc_handler
= &proc_dointvec
,
297 #ifdef CONFIG_LOCK_STAT
299 .ctl_name
= CTL_UNNUMBERED
,
300 .procname
= "lock_stat",
302 .maxlen
= sizeof(int),
304 .proc_handler
= &proc_dointvec
,
308 .ctl_name
= CTL_UNNUMBERED
,
309 .procname
= "sched_features",
310 .data
= &sysctl_sched_features
,
311 .maxlen
= sizeof(unsigned int),
313 .proc_handler
= &proc_dointvec
,
317 .ctl_name
= KERN_PANIC
,
319 .data
= &panic_timeout
,
320 .maxlen
= sizeof(int),
322 .proc_handler
= &proc_dointvec
,
325 .ctl_name
= KERN_CORE_USES_PID
,
326 .procname
= "core_uses_pid",
327 .data
= &core_uses_pid
,
328 .maxlen
= sizeof(int),
330 .proc_handler
= &proc_dointvec
,
332 #ifdef CONFIG_AUDITSYSCALL
334 .ctl_name
= CTL_UNNUMBERED
,
335 .procname
= "audit_argv_kb",
336 .data
= &audit_argv_kb
,
337 .maxlen
= sizeof(int),
339 .proc_handler
= &proc_dointvec
,
343 .ctl_name
= KERN_CORE_PATTERN
,
344 .procname
= "core_pattern",
345 .data
= core_pattern
,
346 .maxlen
= CORENAME_MAX_SIZE
,
348 .proc_handler
= &proc_dostring
,
349 .strategy
= &sysctl_string
,
351 #ifdef CONFIG_PROC_SYSCTL
353 .ctl_name
= KERN_TAINTED
,
354 .procname
= "tainted",
356 .maxlen
= sizeof(int),
358 .proc_handler
= &proc_dointvec_taint
,
362 .ctl_name
= KERN_CAP_BSET
,
363 .procname
= "cap-bound",
365 .maxlen
= sizeof(kernel_cap_t
),
367 .proc_handler
= &proc_dointvec_bset
,
369 #ifdef CONFIG_BLK_DEV_INITRD
371 .ctl_name
= KERN_REALROOTDEV
,
372 .procname
= "real-root-dev",
373 .data
= &real_root_dev
,
374 .maxlen
= sizeof(int),
376 .proc_handler
= &proc_dointvec
,
380 .ctl_name
= CTL_UNNUMBERED
,
381 .procname
= "print-fatal-signals",
382 .data
= &print_fatal_signals
,
383 .maxlen
= sizeof(int),
385 .proc_handler
= &proc_dointvec
,
389 .ctl_name
= KERN_SPARC_REBOOT
,
390 .procname
= "reboot-cmd",
391 .data
= reboot_command
,
394 .proc_handler
= &proc_dostring
,
395 .strategy
= &sysctl_string
,
398 .ctl_name
= KERN_SPARC_STOP_A
,
399 .procname
= "stop-a",
400 .data
= &stop_a_enabled
,
401 .maxlen
= sizeof (int),
403 .proc_handler
= &proc_dointvec
,
406 .ctl_name
= KERN_SPARC_SCONS_PWROFF
,
407 .procname
= "scons-poweroff",
408 .data
= &scons_pwroff
,
409 .maxlen
= sizeof (int),
411 .proc_handler
= &proc_dointvec
,
416 .ctl_name
= KERN_HPPA_PWRSW
,
417 .procname
= "soft-power",
418 .data
= &pwrsw_enabled
,
419 .maxlen
= sizeof (int),
421 .proc_handler
= &proc_dointvec
,
424 .ctl_name
= KERN_HPPA_UNALIGNED
,
425 .procname
= "unaligned-trap",
426 .data
= &unaligned_enabled
,
427 .maxlen
= sizeof (int),
429 .proc_handler
= &proc_dointvec
,
433 .ctl_name
= KERN_CTLALTDEL
,
434 .procname
= "ctrl-alt-del",
436 .maxlen
= sizeof(int),
438 .proc_handler
= &proc_dointvec
,
441 .ctl_name
= KERN_PRINTK
,
442 .procname
= "printk",
443 .data
= &console_loglevel
,
444 .maxlen
= 4*sizeof(int),
446 .proc_handler
= &proc_dointvec
,
450 .ctl_name
= KERN_MODPROBE
,
451 .procname
= "modprobe",
452 .data
= &modprobe_path
,
453 .maxlen
= KMOD_PATH_LEN
,
455 .proc_handler
= &proc_dostring
,
456 .strategy
= &sysctl_string
,
459 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
461 .ctl_name
= KERN_HOTPLUG
,
462 .procname
= "hotplug",
463 .data
= &uevent_helper
,
464 .maxlen
= UEVENT_HELPER_PATH_LEN
,
466 .proc_handler
= &proc_dostring
,
467 .strategy
= &sysctl_string
,
470 #ifdef CONFIG_CHR_DEV_SG
472 .ctl_name
= KERN_SG_BIG_BUFF
,
473 .procname
= "sg-big-buff",
474 .data
= &sg_big_buff
,
475 .maxlen
= sizeof (int),
477 .proc_handler
= &proc_dointvec
,
480 #ifdef CONFIG_BSD_PROCESS_ACCT
482 .ctl_name
= KERN_ACCT
,
485 .maxlen
= 3*sizeof(int),
487 .proc_handler
= &proc_dointvec
,
490 #ifdef CONFIG_MAGIC_SYSRQ
492 .ctl_name
= KERN_SYSRQ
,
494 .data
= &__sysrq_enabled
,
495 .maxlen
= sizeof (int),
497 .proc_handler
= &proc_dointvec
,
500 #ifdef CONFIG_PROC_SYSCTL
502 .ctl_name
= KERN_CADPID
,
503 .procname
= "cad_pid",
505 .maxlen
= sizeof (int),
507 .proc_handler
= &proc_do_cad_pid
,
511 .ctl_name
= KERN_MAX_THREADS
,
512 .procname
= "threads-max",
513 .data
= &max_threads
,
514 .maxlen
= sizeof(int),
516 .proc_handler
= &proc_dointvec
,
519 .ctl_name
= KERN_RANDOM
,
520 .procname
= "random",
522 .child
= random_table
,
524 #ifdef CONFIG_UNIX98_PTYS
526 .ctl_name
= KERN_PTY
,
533 .ctl_name
= KERN_OVERFLOWUID
,
534 .procname
= "overflowuid",
535 .data
= &overflowuid
,
536 .maxlen
= sizeof(int),
538 .proc_handler
= &proc_dointvec_minmax
,
539 .strategy
= &sysctl_intvec
,
540 .extra1
= &minolduid
,
541 .extra2
= &maxolduid
,
544 .ctl_name
= KERN_OVERFLOWGID
,
545 .procname
= "overflowgid",
546 .data
= &overflowgid
,
547 .maxlen
= sizeof(int),
549 .proc_handler
= &proc_dointvec_minmax
,
550 .strategy
= &sysctl_intvec
,
551 .extra1
= &minolduid
,
552 .extra2
= &maxolduid
,
555 #ifdef CONFIG_MATHEMU
557 .ctl_name
= KERN_IEEE_EMULATION_WARNINGS
,
558 .procname
= "ieee_emulation_warnings",
559 .data
= &sysctl_ieee_emulation_warnings
,
560 .maxlen
= sizeof(int),
562 .proc_handler
= &proc_dointvec
,
565 #ifdef CONFIG_NO_IDLE_HZ
567 .ctl_name
= KERN_HZ_TIMER
,
568 .procname
= "hz_timer",
569 .data
= &sysctl_hz_timer
,
570 .maxlen
= sizeof(int),
572 .proc_handler
= &proc_dointvec
,
576 .ctl_name
= KERN_S390_USER_DEBUG_LOGGING
,
577 .procname
= "userprocess_debug",
578 .data
= &sysctl_userprocess_debug
,
579 .maxlen
= sizeof(int),
581 .proc_handler
= &proc_dointvec
,
585 .ctl_name
= KERN_PIDMAX
,
586 .procname
= "pid_max",
588 .maxlen
= sizeof (int),
590 .proc_handler
= &proc_dointvec_minmax
,
591 .strategy
= sysctl_intvec
,
592 .extra1
= &pid_max_min
,
593 .extra2
= &pid_max_max
,
596 .ctl_name
= KERN_PANIC_ON_OOPS
,
597 .procname
= "panic_on_oops",
598 .data
= &panic_on_oops
,
599 .maxlen
= sizeof(int),
601 .proc_handler
= &proc_dointvec
,
604 .ctl_name
= KERN_PRINTK_RATELIMIT
,
605 .procname
= "printk_ratelimit",
606 .data
= &printk_ratelimit_jiffies
,
607 .maxlen
= sizeof(int),
609 .proc_handler
= &proc_dointvec_jiffies
,
610 .strategy
= &sysctl_jiffies
,
613 .ctl_name
= KERN_PRINTK_RATELIMIT_BURST
,
614 .procname
= "printk_ratelimit_burst",
615 .data
= &printk_ratelimit_burst
,
616 .maxlen
= sizeof(int),
618 .proc_handler
= &proc_dointvec
,
621 .ctl_name
= KERN_NGROUPS_MAX
,
622 .procname
= "ngroups_max",
623 .data
= &ngroups_max
,
624 .maxlen
= sizeof (int),
626 .proc_handler
= &proc_dointvec
,
628 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
630 .ctl_name
= KERN_UNKNOWN_NMI_PANIC
,
631 .procname
= "unknown_nmi_panic",
632 .data
= &unknown_nmi_panic
,
633 .maxlen
= sizeof (int),
635 .proc_handler
= &proc_dointvec
,
638 .ctl_name
= KERN_NMI_WATCHDOG
,
639 .procname
= "nmi_watchdog",
640 .data
= &nmi_watchdog_enabled
,
641 .maxlen
= sizeof (int),
643 .proc_handler
= &proc_nmi_enabled
,
646 #if defined(CONFIG_X86)
648 .ctl_name
= KERN_PANIC_ON_NMI
,
649 .procname
= "panic_on_unrecovered_nmi",
650 .data
= &panic_on_unrecovered_nmi
,
651 .maxlen
= sizeof(int),
653 .proc_handler
= &proc_dointvec
,
656 .ctl_name
= KERN_BOOTLOADER_TYPE
,
657 .procname
= "bootloader_type",
658 .data
= &bootloader_type
,
659 .maxlen
= sizeof (int),
661 .proc_handler
= &proc_dointvec
,
664 .ctl_name
= CTL_UNNUMBERED
,
665 .procname
= "kstack_depth_to_print",
666 .data
= &kstack_depth_to_print
,
667 .maxlen
= sizeof(int),
669 .proc_handler
= &proc_dointvec
,
672 #if defined(CONFIG_MMU)
674 .ctl_name
= KERN_RANDOMIZE
,
675 .procname
= "randomize_va_space",
676 .data
= &randomize_va_space
,
677 .maxlen
= sizeof(int),
679 .proc_handler
= &proc_dointvec
,
682 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
684 .ctl_name
= KERN_SPIN_RETRY
,
685 .procname
= "spin_retry",
687 .maxlen
= sizeof (int),
689 .proc_handler
= &proc_dointvec
,
692 #ifdef CONFIG_ACPI_SLEEP
694 .ctl_name
= KERN_ACPI_VIDEO_FLAGS
,
695 .procname
= "acpi_video_flags",
696 .data
= &acpi_realmode_flags
,
697 .maxlen
= sizeof (unsigned long),
699 .proc_handler
= &proc_doulongvec_minmax
,
704 .ctl_name
= KERN_IA64_UNALIGNED
,
705 .procname
= "ignore-unaligned-usertrap",
706 .data
= &no_unaligned_warning
,
707 .maxlen
= sizeof (int),
709 .proc_handler
= &proc_dointvec
,
714 .ctl_name
= KERN_COMPAT_LOG
,
715 .procname
= "compat-log",
717 .maxlen
= sizeof (int),
719 .proc_handler
= &proc_dointvec
,
722 #ifdef CONFIG_RT_MUTEXES
724 .ctl_name
= KERN_MAX_LOCK_DEPTH
,
725 .procname
= "max_lock_depth",
726 .data
= &max_lock_depth
,
727 .maxlen
= sizeof(int),
729 .proc_handler
= &proc_dointvec
,
732 #ifdef CONFIG_PROC_FS
734 .ctl_name
= CTL_UNNUMBERED
,
735 .procname
= "maps_protect",
736 .data
= &maps_protect
,
737 .maxlen
= sizeof(int),
739 .proc_handler
= &proc_dointvec
,
743 .ctl_name
= CTL_UNNUMBERED
,
744 .procname
= "poweroff_cmd",
745 .data
= &poweroff_cmd
,
746 .maxlen
= POWEROFF_CMD_PATH_LEN
,
748 .proc_handler
= &proc_dostring
,
749 .strategy
= &sysctl_string
,
755 /* Constants for minimum and maximum testing in vm_table.
756 We use these as one-element integer vectors. */
759 static int one_hundred
= 100;
762 static ctl_table vm_table
[] = {
764 .ctl_name
= VM_OVERCOMMIT_MEMORY
,
765 .procname
= "overcommit_memory",
766 .data
= &sysctl_overcommit_memory
,
767 .maxlen
= sizeof(sysctl_overcommit_memory
),
769 .proc_handler
= &proc_dointvec
,
772 .ctl_name
= VM_PANIC_ON_OOM
,
773 .procname
= "panic_on_oom",
774 .data
= &sysctl_panic_on_oom
,
775 .maxlen
= sizeof(sysctl_panic_on_oom
),
777 .proc_handler
= &proc_dointvec
,
780 .ctl_name
= VM_OVERCOMMIT_RATIO
,
781 .procname
= "overcommit_ratio",
782 .data
= &sysctl_overcommit_ratio
,
783 .maxlen
= sizeof(sysctl_overcommit_ratio
),
785 .proc_handler
= &proc_dointvec
,
788 .ctl_name
= VM_PAGE_CLUSTER
,
789 .procname
= "page-cluster",
790 .data
= &page_cluster
,
791 .maxlen
= sizeof(int),
793 .proc_handler
= &proc_dointvec
,
796 .ctl_name
= VM_DIRTY_BACKGROUND
,
797 .procname
= "dirty_background_ratio",
798 .data
= &dirty_background_ratio
,
799 .maxlen
= sizeof(dirty_background_ratio
),
801 .proc_handler
= &proc_dointvec_minmax
,
802 .strategy
= &sysctl_intvec
,
804 .extra2
= &one_hundred
,
807 .ctl_name
= VM_DIRTY_RATIO
,
808 .procname
= "dirty_ratio",
809 .data
= &vm_dirty_ratio
,
810 .maxlen
= sizeof(vm_dirty_ratio
),
812 .proc_handler
= &proc_dointvec_minmax
,
813 .strategy
= &sysctl_intvec
,
815 .extra2
= &one_hundred
,
818 .ctl_name
= VM_DIRTY_WB_CS
,
819 .procname
= "dirty_writeback_centisecs",
820 .data
= &dirty_writeback_interval
,
821 .maxlen
= sizeof(dirty_writeback_interval
),
823 .proc_handler
= &dirty_writeback_centisecs_handler
,
826 .ctl_name
= VM_DIRTY_EXPIRE_CS
,
827 .procname
= "dirty_expire_centisecs",
828 .data
= &dirty_expire_interval
,
829 .maxlen
= sizeof(dirty_expire_interval
),
831 .proc_handler
= &proc_dointvec_userhz_jiffies
,
834 .ctl_name
= VM_NR_PDFLUSH_THREADS
,
835 .procname
= "nr_pdflush_threads",
836 .data
= &nr_pdflush_threads
,
837 .maxlen
= sizeof nr_pdflush_threads
,
838 .mode
= 0444 /* read-only*/,
839 .proc_handler
= &proc_dointvec
,
842 .ctl_name
= VM_SWAPPINESS
,
843 .procname
= "swappiness",
844 .data
= &vm_swappiness
,
845 .maxlen
= sizeof(vm_swappiness
),
847 .proc_handler
= &proc_dointvec_minmax
,
848 .strategy
= &sysctl_intvec
,
850 .extra2
= &one_hundred
,
852 #ifdef CONFIG_HUGETLB_PAGE
854 .ctl_name
= VM_HUGETLB_PAGES
,
855 .procname
= "nr_hugepages",
856 .data
= &max_huge_pages
,
857 .maxlen
= sizeof(unsigned long),
859 .proc_handler
= &hugetlb_sysctl_handler
,
860 .extra1
= (void *)&hugetlb_zero
,
861 .extra2
= (void *)&hugetlb_infinity
,
864 .ctl_name
= VM_HUGETLB_GROUP
,
865 .procname
= "hugetlb_shm_group",
866 .data
= &sysctl_hugetlb_shm_group
,
867 .maxlen
= sizeof(gid_t
),
869 .proc_handler
= &proc_dointvec
,
872 .ctl_name
= CTL_UNNUMBERED
,
873 .procname
= "hugepages_treat_as_movable",
874 .data
= &hugepages_treat_as_movable
,
875 .maxlen
= sizeof(int),
877 .proc_handler
= &hugetlb_treat_movable_handler
,
881 .ctl_name
= VM_LOWMEM_RESERVE_RATIO
,
882 .procname
= "lowmem_reserve_ratio",
883 .data
= &sysctl_lowmem_reserve_ratio
,
884 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
886 .proc_handler
= &lowmem_reserve_ratio_sysctl_handler
,
887 .strategy
= &sysctl_intvec
,
890 .ctl_name
= VM_DROP_PAGECACHE
,
891 .procname
= "drop_caches",
892 .data
= &sysctl_drop_caches
,
893 .maxlen
= sizeof(int),
895 .proc_handler
= drop_caches_sysctl_handler
,
896 .strategy
= &sysctl_intvec
,
899 .ctl_name
= VM_MIN_FREE_KBYTES
,
900 .procname
= "min_free_kbytes",
901 .data
= &min_free_kbytes
,
902 .maxlen
= sizeof(min_free_kbytes
),
904 .proc_handler
= &min_free_kbytes_sysctl_handler
,
905 .strategy
= &sysctl_intvec
,
909 .ctl_name
= VM_PERCPU_PAGELIST_FRACTION
,
910 .procname
= "percpu_pagelist_fraction",
911 .data
= &percpu_pagelist_fraction
,
912 .maxlen
= sizeof(percpu_pagelist_fraction
),
914 .proc_handler
= &percpu_pagelist_fraction_sysctl_handler
,
915 .strategy
= &sysctl_intvec
,
916 .extra1
= &min_percpu_pagelist_fract
,
920 .ctl_name
= VM_MAX_MAP_COUNT
,
921 .procname
= "max_map_count",
922 .data
= &sysctl_max_map_count
,
923 .maxlen
= sizeof(sysctl_max_map_count
),
925 .proc_handler
= &proc_dointvec
929 .ctl_name
= VM_LAPTOP_MODE
,
930 .procname
= "laptop_mode",
931 .data
= &laptop_mode
,
932 .maxlen
= sizeof(laptop_mode
),
934 .proc_handler
= &proc_dointvec_jiffies
,
935 .strategy
= &sysctl_jiffies
,
938 .ctl_name
= VM_BLOCK_DUMP
,
939 .procname
= "block_dump",
941 .maxlen
= sizeof(block_dump
),
943 .proc_handler
= &proc_dointvec
,
944 .strategy
= &sysctl_intvec
,
948 .ctl_name
= VM_VFS_CACHE_PRESSURE
,
949 .procname
= "vfs_cache_pressure",
950 .data
= &sysctl_vfs_cache_pressure
,
951 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
953 .proc_handler
= &proc_dointvec
,
954 .strategy
= &sysctl_intvec
,
957 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
959 .ctl_name
= VM_LEGACY_VA_LAYOUT
,
960 .procname
= "legacy_va_layout",
961 .data
= &sysctl_legacy_va_layout
,
962 .maxlen
= sizeof(sysctl_legacy_va_layout
),
964 .proc_handler
= &proc_dointvec
,
965 .strategy
= &sysctl_intvec
,
971 .ctl_name
= VM_ZONE_RECLAIM_MODE
,
972 .procname
= "zone_reclaim_mode",
973 .data
= &zone_reclaim_mode
,
974 .maxlen
= sizeof(zone_reclaim_mode
),
976 .proc_handler
= &proc_dointvec
,
977 .strategy
= &sysctl_intvec
,
981 .ctl_name
= VM_MIN_UNMAPPED
,
982 .procname
= "min_unmapped_ratio",
983 .data
= &sysctl_min_unmapped_ratio
,
984 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
986 .proc_handler
= &sysctl_min_unmapped_ratio_sysctl_handler
,
987 .strategy
= &sysctl_intvec
,
989 .extra2
= &one_hundred
,
992 .ctl_name
= VM_MIN_SLAB
,
993 .procname
= "min_slab_ratio",
994 .data
= &sysctl_min_slab_ratio
,
995 .maxlen
= sizeof(sysctl_min_slab_ratio
),
997 .proc_handler
= &sysctl_min_slab_ratio_sysctl_handler
,
998 .strategy
= &sysctl_intvec
,
1000 .extra2
= &one_hundred
,
1005 .ctl_name
= CTL_UNNUMBERED
,
1006 .procname
= "stat_interval",
1007 .data
= &sysctl_stat_interval
,
1008 .maxlen
= sizeof(sysctl_stat_interval
),
1010 .proc_handler
= &proc_dointvec_jiffies
,
1011 .strategy
= &sysctl_jiffies
,
1014 #ifdef CONFIG_SECURITY
1016 .ctl_name
= CTL_UNNUMBERED
,
1017 .procname
= "mmap_min_addr",
1018 .data
= &mmap_min_addr
,
1019 .maxlen
= sizeof(unsigned long),
1021 .proc_handler
= &proc_doulongvec_minmax
,
1025 .ctl_name
= CTL_UNNUMBERED
,
1026 .procname
= "numa_zonelist_order",
1027 .data
= &numa_zonelist_order
,
1028 .maxlen
= NUMA_ZONELIST_ORDER_LEN
,
1030 .proc_handler
= &numa_zonelist_order_handler
,
1031 .strategy
= &sysctl_string
,
1035 #if defined(CONFIG_X86_32) || \
1036 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1038 .ctl_name
= VM_VDSO_ENABLED
,
1039 .procname
= "vdso_enabled",
1040 .data
= &vdso_enabled
,
1041 .maxlen
= sizeof(vdso_enabled
),
1043 .proc_handler
= &proc_dointvec
,
1044 .strategy
= &sysctl_intvec
,
1049 * NOTE: do not add new entries to this table unless you have read
1050 * Documentation/sysctl/ctl_unnumbered.txt
1055 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1056 static ctl_table binfmt_misc_table
[] = {
1061 static ctl_table fs_table
[] = {
1063 .ctl_name
= FS_NRINODE
,
1064 .procname
= "inode-nr",
1065 .data
= &inodes_stat
,
1066 .maxlen
= 2*sizeof(int),
1068 .proc_handler
= &proc_dointvec
,
1071 .ctl_name
= FS_STATINODE
,
1072 .procname
= "inode-state",
1073 .data
= &inodes_stat
,
1074 .maxlen
= 7*sizeof(int),
1076 .proc_handler
= &proc_dointvec
,
1079 .ctl_name
= FS_NRFILE
,
1080 .procname
= "file-nr",
1081 .data
= &files_stat
,
1082 .maxlen
= 3*sizeof(int),
1084 .proc_handler
= &proc_nr_files
,
1087 .ctl_name
= FS_MAXFILE
,
1088 .procname
= "file-max",
1089 .data
= &files_stat
.max_files
,
1090 .maxlen
= sizeof(int),
1092 .proc_handler
= &proc_dointvec
,
1095 .ctl_name
= FS_DENTRY
,
1096 .procname
= "dentry-state",
1097 .data
= &dentry_stat
,
1098 .maxlen
= 6*sizeof(int),
1100 .proc_handler
= &proc_dointvec
,
1103 .ctl_name
= FS_OVERFLOWUID
,
1104 .procname
= "overflowuid",
1105 .data
= &fs_overflowuid
,
1106 .maxlen
= sizeof(int),
1108 .proc_handler
= &proc_dointvec_minmax
,
1109 .strategy
= &sysctl_intvec
,
1110 .extra1
= &minolduid
,
1111 .extra2
= &maxolduid
,
1114 .ctl_name
= FS_OVERFLOWGID
,
1115 .procname
= "overflowgid",
1116 .data
= &fs_overflowgid
,
1117 .maxlen
= sizeof(int),
1119 .proc_handler
= &proc_dointvec_minmax
,
1120 .strategy
= &sysctl_intvec
,
1121 .extra1
= &minolduid
,
1122 .extra2
= &maxolduid
,
1125 .ctl_name
= FS_LEASES
,
1126 .procname
= "leases-enable",
1127 .data
= &leases_enable
,
1128 .maxlen
= sizeof(int),
1130 .proc_handler
= &proc_dointvec
,
1132 #ifdef CONFIG_DNOTIFY
1134 .ctl_name
= FS_DIR_NOTIFY
,
1135 .procname
= "dir-notify-enable",
1136 .data
= &dir_notify_enable
,
1137 .maxlen
= sizeof(int),
1139 .proc_handler
= &proc_dointvec
,
1144 .ctl_name
= FS_LEASE_TIME
,
1145 .procname
= "lease-break-time",
1146 .data
= &lease_break_time
,
1147 .maxlen
= sizeof(int),
1149 .proc_handler
= &proc_dointvec_minmax
,
1150 .strategy
= &sysctl_intvec
,
1155 .ctl_name
= FS_AIO_NR
,
1156 .procname
= "aio-nr",
1158 .maxlen
= sizeof(aio_nr
),
1160 .proc_handler
= &proc_doulongvec_minmax
,
1163 .ctl_name
= FS_AIO_MAX_NR
,
1164 .procname
= "aio-max-nr",
1165 .data
= &aio_max_nr
,
1166 .maxlen
= sizeof(aio_max_nr
),
1168 .proc_handler
= &proc_doulongvec_minmax
,
1170 #ifdef CONFIG_INOTIFY_USER
1172 .ctl_name
= FS_INOTIFY
,
1173 .procname
= "inotify",
1175 .child
= inotify_table
,
1180 .ctl_name
= KERN_SETUID_DUMPABLE
,
1181 .procname
= "suid_dumpable",
1182 .data
= &suid_dumpable
,
1183 .maxlen
= sizeof(int),
1185 .proc_handler
= &proc_dointvec
,
1187 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1189 .ctl_name
= CTL_UNNUMBERED
,
1190 .procname
= "binfmt_misc",
1192 .child
= binfmt_misc_table
,
1196 * NOTE: do not add new entries to this table unless you have read
1197 * Documentation/sysctl/ctl_unnumbered.txt
1202 static ctl_table debug_table
[] = {
1206 static ctl_table dev_table
[] = {
1210 static DEFINE_SPINLOCK(sysctl_lock
);
1212 /* called under sysctl_lock */
1213 static int use_table(struct ctl_table_header
*p
)
1215 if (unlikely(p
->unregistering
))
1221 /* called under sysctl_lock */
1222 static void unuse_table(struct ctl_table_header
*p
)
1225 if (unlikely(p
->unregistering
))
1226 complete(p
->unregistering
);
1229 /* called under sysctl_lock, will reacquire if has to wait */
1230 static void start_unregistering(struct ctl_table_header
*p
)
1233 * if p->used is 0, nobody will ever touch that entry again;
1234 * we'll eliminate all paths to it before dropping sysctl_lock
1236 if (unlikely(p
->used
)) {
1237 struct completion wait
;
1238 init_completion(&wait
);
1239 p
->unregistering
= &wait
;
1240 spin_unlock(&sysctl_lock
);
1241 wait_for_completion(&wait
);
1242 spin_lock(&sysctl_lock
);
1245 * do not remove from the list until nobody holds it; walking the
1246 * list in do_sysctl() relies on that.
1248 list_del_init(&p
->ctl_entry
);
1251 void sysctl_head_finish(struct ctl_table_header
*head
)
1255 spin_lock(&sysctl_lock
);
1257 spin_unlock(&sysctl_lock
);
1260 struct ctl_table_header
*sysctl_head_next(struct ctl_table_header
*prev
)
1262 struct ctl_table_header
*head
;
1263 struct list_head
*tmp
;
1264 spin_lock(&sysctl_lock
);
1266 tmp
= &prev
->ctl_entry
;
1270 tmp
= &root_table_header
.ctl_entry
;
1272 head
= list_entry(tmp
, struct ctl_table_header
, ctl_entry
);
1274 if (!use_table(head
))
1276 spin_unlock(&sysctl_lock
);
1280 if (tmp
== &root_table_header
.ctl_entry
)
1283 spin_unlock(&sysctl_lock
);
1287 #ifdef CONFIG_SYSCTL_SYSCALL
1288 int do_sysctl(int __user
*name
, int nlen
, void __user
*oldval
, size_t __user
*oldlenp
,
1289 void __user
*newval
, size_t newlen
)
1291 struct ctl_table_header
*head
;
1292 int error
= -ENOTDIR
;
1294 if (nlen
<= 0 || nlen
>= CTL_MAXNAME
)
1298 if (!oldlenp
|| get_user(old_len
, oldlenp
))
1302 for (head
= sysctl_head_next(NULL
); head
;
1303 head
= sysctl_head_next(head
)) {
1304 error
= parse_table(name
, nlen
, oldval
, oldlenp
,
1305 newval
, newlen
, head
->ctl_table
);
1306 if (error
!= -ENOTDIR
) {
1307 sysctl_head_finish(head
);
1314 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
1316 struct __sysctl_args tmp
;
1319 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
1323 error
= do_sysctl(tmp
.name
, tmp
.nlen
, tmp
.oldval
, tmp
.oldlenp
,
1324 tmp
.newval
, tmp
.newlen
);
1328 #endif /* CONFIG_SYSCTL_SYSCALL */
1331 * sysctl_perm does NOT grant the superuser all rights automatically, because
1332 * some sysctl variables are readonly even to root.
1335 static int test_perm(int mode
, int op
)
1339 else if (in_egroup_p(0))
1341 if ((mode
& op
& 0007) == op
)
1346 int sysctl_perm(ctl_table
*table
, int op
)
1349 error
= security_sysctl(table
, op
);
1352 return test_perm(table
->mode
, op
);
1355 #ifdef CONFIG_SYSCTL_SYSCALL
1356 static int parse_table(int __user
*name
, int nlen
,
1357 void __user
*oldval
, size_t __user
*oldlenp
,
1358 void __user
*newval
, size_t newlen
,
1365 if (get_user(n
, name
))
1367 for ( ; table
->ctl_name
|| table
->procname
; table
++) {
1368 if (!table
->ctl_name
)
1370 if (n
== table
->ctl_name
) {
1373 if (sysctl_perm(table
, 001))
1377 table
= table
->child
;
1380 error
= do_sysctl_strategy(table
, name
, nlen
,
1389 /* Perform the actual read/write of a sysctl table entry. */
1390 int do_sysctl_strategy (ctl_table
*table
,
1391 int __user
*name
, int nlen
,
1392 void __user
*oldval
, size_t __user
*oldlenp
,
1393 void __user
*newval
, size_t newlen
)
1402 if (sysctl_perm(table
, op
))
1405 if (table
->strategy
) {
1406 rc
= table
->strategy(table
, name
, nlen
, oldval
, oldlenp
,
1414 /* If there is no strategy routine, or if the strategy returns
1415 * zero, proceed with automatic r/w */
1416 if (table
->data
&& table
->maxlen
) {
1417 if (oldval
&& oldlenp
) {
1418 if (get_user(len
, oldlenp
))
1421 if (len
> table
->maxlen
)
1422 len
= table
->maxlen
;
1423 if(copy_to_user(oldval
, table
->data
, len
))
1425 if(put_user(len
, oldlenp
))
1429 if (newval
&& newlen
) {
1431 if (len
> table
->maxlen
)
1432 len
= table
->maxlen
;
1433 if(copy_from_user(table
->data
, newval
, len
))
1439 #endif /* CONFIG_SYSCTL_SYSCALL */
1441 static void sysctl_set_parent(struct ctl_table
*parent
, struct ctl_table
*table
)
1443 for (; table
->ctl_name
|| table
->procname
; table
++) {
1444 table
->parent
= parent
;
1446 sysctl_set_parent(table
, table
->child
);
1450 static __init
int sysctl_init(void)
1452 sysctl_set_parent(NULL
, root_table
);
1456 core_initcall(sysctl_init
);
1459 * register_sysctl_table - register a sysctl hierarchy
1460 * @table: the top-level table structure
1462 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1463 * array. An entry with a ctl_name of 0 terminates the table.
1465 * The members of the &ctl_table structure are used as follows:
1467 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1468 * must be unique within that level of sysctl
1470 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1471 * enter a sysctl file
1473 * data - a pointer to data for use by proc_handler
1475 * maxlen - the maximum size in bytes of the data
1477 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1479 * child - a pointer to the child sysctl table if this entry is a directory, or
1482 * proc_handler - the text handler routine (described below)
1484 * strategy - the strategy routine (described below)
1486 * de - for internal use by the sysctl routines
1488 * extra1, extra2 - extra pointers usable by the proc handler routines
1490 * Leaf nodes in the sysctl tree will be represented by a single file
1491 * under /proc; non-leaf nodes will be represented by directories.
1493 * sysctl(2) can automatically manage read and write requests through
1494 * the sysctl table. The data and maxlen fields of the ctl_table
1495 * struct enable minimal validation of the values being written to be
1496 * performed, and the mode field allows minimal authentication.
1498 * More sophisticated management can be enabled by the provision of a
1499 * strategy routine with the table entry. This will be called before
1500 * any automatic read or write of the data is performed.
1502 * The strategy routine may return
1504 * < 0 - Error occurred (error is passed to user process)
1506 * 0 - OK - proceed with automatic read or write.
1508 * > 0 - OK - read or write has been done by the strategy routine, so
1509 * return immediately.
1511 * There must be a proc_handler routine for any terminal nodes
1512 * mirrored under /proc/sys (non-terminals are handled by a built-in
1513 * directory handler). Several default handlers are available to
1514 * cover common cases -
1516 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1517 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1518 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1520 * It is the handler's job to read the input buffer from user memory
1521 * and process it. The handler should return 0 on success.
1523 * This routine returns %NULL on a failure to register, and a pointer
1524 * to the table header on success.
1526 struct ctl_table_header
*register_sysctl_table(ctl_table
* table
)
1528 struct ctl_table_header
*tmp
;
1529 tmp
= kmalloc(sizeof(struct ctl_table_header
), GFP_KERNEL
);
1532 tmp
->ctl_table
= table
;
1533 INIT_LIST_HEAD(&tmp
->ctl_entry
);
1535 tmp
->unregistering
= NULL
;
1536 sysctl_set_parent(NULL
, table
);
1537 spin_lock(&sysctl_lock
);
1538 list_add_tail(&tmp
->ctl_entry
, &root_table_header
.ctl_entry
);
1539 spin_unlock(&sysctl_lock
);
1544 * unregister_sysctl_table - unregister a sysctl table hierarchy
1545 * @header: the header returned from register_sysctl_table
1547 * Unregisters the sysctl table and all children. proc entries may not
1548 * actually be removed until they are no longer used by anyone.
1550 void unregister_sysctl_table(struct ctl_table_header
* header
)
1553 spin_lock(&sysctl_lock
);
1554 start_unregistering(header
);
1555 spin_unlock(&sysctl_lock
);
1559 #else /* !CONFIG_SYSCTL */
1560 struct ctl_table_header
*register_sysctl_table(ctl_table
* table
)
1565 void unregister_sysctl_table(struct ctl_table_header
* table
)
1569 #endif /* CONFIG_SYSCTL */
1575 #ifdef CONFIG_PROC_SYSCTL
1577 static int _proc_do_string(void* data
, int maxlen
, int write
,
1578 struct file
*filp
, void __user
*buffer
,
1579 size_t *lenp
, loff_t
*ppos
)
1585 if (!data
|| !maxlen
|| !*lenp
) {
1593 while (len
< *lenp
) {
1594 if (get_user(c
, p
++))
1596 if (c
== 0 || c
== '\n')
1602 if(copy_from_user(data
, buffer
, len
))
1604 ((char *) data
)[len
] = 0;
1622 if(copy_to_user(buffer
, data
, len
))
1625 if(put_user('\n', ((char __user
*) buffer
) + len
))
1636 * proc_dostring - read a string sysctl
1637 * @table: the sysctl table
1638 * @write: %TRUE if this is a write to the sysctl file
1639 * @filp: the file structure
1640 * @buffer: the user buffer
1641 * @lenp: the size of the user buffer
1642 * @ppos: file position
1644 * Reads/writes a string from/to the user buffer. If the kernel
1645 * buffer provided is not large enough to hold the string, the
1646 * string is truncated. The copied string is %NULL-terminated.
1647 * If the string is being read by the user process, it is copied
1648 * and a newline '\n' is added. It is truncated if the buffer is
1651 * Returns 0 on success.
1653 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
1654 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1656 return _proc_do_string(table
->data
, table
->maxlen
, write
, filp
,
1657 buffer
, lenp
, ppos
);
1661 static int do_proc_dointvec_conv(int *negp
, unsigned long *lvalp
,
1663 int write
, void *data
)
1666 *valp
= *negp
? -*lvalp
: *lvalp
;
1671 *lvalp
= (unsigned long)-val
;
1674 *lvalp
= (unsigned long)val
;
1680 static int __do_proc_dointvec(void *tbl_data
, ctl_table
*table
,
1681 int write
, struct file
*filp
, void __user
*buffer
,
1682 size_t *lenp
, loff_t
*ppos
,
1683 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1684 int write
, void *data
),
1687 #define TMPBUFLEN 21
1688 int *i
, vleft
, first
=1, neg
, val
;
1692 char buf
[TMPBUFLEN
], *p
;
1693 char __user
*s
= buffer
;
1695 if (!tbl_data
|| !table
->maxlen
|| !*lenp
||
1696 (*ppos
&& !write
)) {
1701 i
= (int *) tbl_data
;
1702 vleft
= table
->maxlen
/ sizeof(*i
);
1706 conv
= do_proc_dointvec_conv
;
1708 for (; left
&& vleft
--; i
++, first
=0) {
1723 if (len
> sizeof(buf
) - 1)
1724 len
= sizeof(buf
) - 1;
1725 if (copy_from_user(buf
, s
, len
))
1729 if (*p
== '-' && left
> 1) {
1733 if (*p
< '0' || *p
> '9')
1736 lval
= simple_strtoul(p
, &p
, 0);
1739 if ((len
< left
) && *p
&& !isspace(*p
))
1746 if (conv(&neg
, &lval
, i
, 1, data
))
1753 if (conv(&neg
, &lval
, i
, 0, data
))
1756 sprintf(p
, "%s%lu", neg
? "-" : "", lval
);
1760 if(copy_to_user(s
, buf
, len
))
1767 if (!write
&& !first
&& left
) {
1768 if(put_user('\n', s
))
1775 if (get_user(c
, s
++))
1790 static int do_proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1791 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
1792 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1793 int write
, void *data
),
1796 return __do_proc_dointvec(table
->data
, table
, write
, filp
,
1797 buffer
, lenp
, ppos
, conv
, data
);
1801 * proc_dointvec - read a vector of integers
1802 * @table: the sysctl table
1803 * @write: %TRUE if this is a write to the sysctl file
1804 * @filp: the file structure
1805 * @buffer: the user buffer
1806 * @lenp: the size of the user buffer
1807 * @ppos: file position
1809 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1810 * values from/to the user buffer, treated as an ASCII string.
1812 * Returns 0 on success.
1814 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1815 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1817 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1825 static int do_proc_dointvec_bset_conv(int *negp
, unsigned long *lvalp
,
1827 int write
, void *data
)
1829 int op
= *(int *)data
;
1831 int val
= *negp
? -*lvalp
: *lvalp
;
1833 case OP_SET
: *valp
= val
; break;
1834 case OP_AND
: *valp
&= val
; break;
1835 case OP_OR
: *valp
|= val
; break;
1841 *lvalp
= (unsigned long)-val
;
1844 *lvalp
= (unsigned long)val
;
1851 * init may raise the set.
1854 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
1855 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1859 if (write
&& !capable(CAP_SYS_MODULE
)) {
1863 op
= is_init(current
) ? OP_SET
: OP_AND
;
1864 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1865 do_proc_dointvec_bset_conv
,&op
);
1869 * Taint values can only be increased
1871 static int proc_dointvec_taint(ctl_table
*table
, int write
, struct file
*filp
,
1872 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1876 if (write
&& !capable(CAP_SYS_ADMIN
))
1880 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1881 do_proc_dointvec_bset_conv
,&op
);
1884 struct do_proc_dointvec_minmax_conv_param
{
1889 static int do_proc_dointvec_minmax_conv(int *negp
, unsigned long *lvalp
,
1891 int write
, void *data
)
1893 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
1895 int val
= *negp
? -*lvalp
: *lvalp
;
1896 if ((param
->min
&& *param
->min
> val
) ||
1897 (param
->max
&& *param
->max
< val
))
1904 *lvalp
= (unsigned long)-val
;
1907 *lvalp
= (unsigned long)val
;
1914 * proc_dointvec_minmax - read a vector of integers with min/max values
1915 * @table: the sysctl table
1916 * @write: %TRUE if this is a write to the sysctl file
1917 * @filp: the file structure
1918 * @buffer: the user buffer
1919 * @lenp: the size of the user buffer
1920 * @ppos: file position
1922 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1923 * values from/to the user buffer, treated as an ASCII string.
1925 * This routine will ensure the values are within the range specified by
1926 * table->extra1 (min) and table->extra2 (max).
1928 * Returns 0 on success.
1930 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
1931 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1933 struct do_proc_dointvec_minmax_conv_param param
= {
1934 .min
= (int *) table
->extra1
,
1935 .max
= (int *) table
->extra2
,
1937 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
1938 do_proc_dointvec_minmax_conv
, ¶m
);
1941 static int __do_proc_doulongvec_minmax(void *data
, ctl_table
*table
, int write
,
1943 void __user
*buffer
,
1944 size_t *lenp
, loff_t
*ppos
,
1945 unsigned long convmul
,
1946 unsigned long convdiv
)
1948 #define TMPBUFLEN 21
1949 unsigned long *i
, *min
, *max
, val
;
1950 int vleft
, first
=1, neg
;
1952 char buf
[TMPBUFLEN
], *p
;
1953 char __user
*s
= buffer
;
1955 if (!data
|| !table
->maxlen
|| !*lenp
||
1956 (*ppos
&& !write
)) {
1961 i
= (unsigned long *) data
;
1962 min
= (unsigned long *) table
->extra1
;
1963 max
= (unsigned long *) table
->extra2
;
1964 vleft
= table
->maxlen
/ sizeof(unsigned long);
1967 for (; left
&& vleft
--; i
++, min
++, max
++, first
=0) {
1982 if (len
> TMPBUFLEN
-1)
1984 if (copy_from_user(buf
, s
, len
))
1988 if (*p
== '-' && left
> 1) {
1992 if (*p
< '0' || *p
> '9')
1994 val
= simple_strtoul(p
, &p
, 0) * convmul
/ convdiv
;
1996 if ((len
< left
) && *p
&& !isspace(*p
))
2005 if ((min
&& val
< *min
) || (max
&& val
> *max
))
2012 sprintf(p
, "%lu", convdiv
* (*i
) / convmul
);
2016 if(copy_to_user(s
, buf
, len
))
2023 if (!write
&& !first
&& left
) {
2024 if(put_user('\n', s
))
2031 if (get_user(c
, s
++))
2046 static int do_proc_doulongvec_minmax(ctl_table
*table
, int write
,
2048 void __user
*buffer
,
2049 size_t *lenp
, loff_t
*ppos
,
2050 unsigned long convmul
,
2051 unsigned long convdiv
)
2053 return __do_proc_doulongvec_minmax(table
->data
, table
, write
,
2054 filp
, buffer
, lenp
, ppos
, convmul
, convdiv
);
2058 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2059 * @table: the sysctl table
2060 * @write: %TRUE if this is a write to the sysctl file
2061 * @filp: the file structure
2062 * @buffer: the user buffer
2063 * @lenp: the size of the user buffer
2064 * @ppos: file position
2066 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2067 * values from/to the user buffer, treated as an ASCII string.
2069 * This routine will ensure the values are within the range specified by
2070 * table->extra1 (min) and table->extra2 (max).
2072 * Returns 0 on success.
2074 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2075 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2077 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
, lenp
, ppos
, 1l, 1l);
2081 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2082 * @table: the sysctl table
2083 * @write: %TRUE if this is a write to the sysctl file
2084 * @filp: the file structure
2085 * @buffer: the user buffer
2086 * @lenp: the size of the user buffer
2087 * @ppos: file position
2089 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2090 * values from/to the user buffer, treated as an ASCII string. The values
2091 * are treated as milliseconds, and converted to jiffies when they are stored.
2093 * This routine will ensure the values are within the range specified by
2094 * table->extra1 (min) and table->extra2 (max).
2096 * Returns 0 on success.
2098 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2100 void __user
*buffer
,
2101 size_t *lenp
, loff_t
*ppos
)
2103 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
,
2104 lenp
, ppos
, HZ
, 1000l);
2108 static int do_proc_dointvec_jiffies_conv(int *negp
, unsigned long *lvalp
,
2110 int write
, void *data
)
2113 if (*lvalp
> LONG_MAX
/ HZ
)
2115 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2121 lval
= (unsigned long)-val
;
2124 lval
= (unsigned long)val
;
2131 static int do_proc_dointvec_userhz_jiffies_conv(int *negp
, unsigned long *lvalp
,
2133 int write
, void *data
)
2136 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2138 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2144 lval
= (unsigned long)-val
;
2147 lval
= (unsigned long)val
;
2149 *lvalp
= jiffies_to_clock_t(lval
);
2154 static int do_proc_dointvec_ms_jiffies_conv(int *negp
, unsigned long *lvalp
,
2156 int write
, void *data
)
2159 *valp
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2165 lval
= (unsigned long)-val
;
2168 lval
= (unsigned long)val
;
2170 *lvalp
= jiffies_to_msecs(lval
);
2176 * proc_dointvec_jiffies - read a vector of integers as seconds
2177 * @table: the sysctl table
2178 * @write: %TRUE if this is a write to the sysctl file
2179 * @filp: the file structure
2180 * @buffer: the user buffer
2181 * @lenp: the size of the user buffer
2182 * @ppos: file position
2184 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2185 * values from/to the user buffer, treated as an ASCII string.
2186 * The values read are assumed to be in seconds, and are converted into
2189 * Returns 0 on success.
2191 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2192 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2194 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2195 do_proc_dointvec_jiffies_conv
,NULL
);
2199 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2200 * @table: the sysctl table
2201 * @write: %TRUE if this is a write to the sysctl file
2202 * @filp: the file structure
2203 * @buffer: the user buffer
2204 * @lenp: the size of the user buffer
2205 * @ppos: pointer to the file position
2207 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2208 * values from/to the user buffer, treated as an ASCII string.
2209 * The values read are assumed to be in 1/USER_HZ seconds, and
2210 * are converted into jiffies.
2212 * Returns 0 on success.
2214 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2215 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2217 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2218 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2222 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2223 * @table: the sysctl table
2224 * @write: %TRUE if this is a write to the sysctl file
2225 * @filp: the file structure
2226 * @buffer: the user buffer
2227 * @lenp: the size of the user buffer
2228 * @ppos: file position
2229 * @ppos: the current position in the file
2231 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2232 * values from/to the user buffer, treated as an ASCII string.
2233 * The values read are assumed to be in 1/1000 seconds, and
2234 * are converted into jiffies.
2236 * Returns 0 on success.
2238 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2239 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2241 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2242 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2245 static int proc_do_cad_pid(ctl_table
*table
, int write
, struct file
*filp
,
2246 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2248 struct pid
*new_pid
;
2252 tmp
= pid_nr(cad_pid
);
2254 r
= __do_proc_dointvec(&tmp
, table
, write
, filp
, buffer
,
2255 lenp
, ppos
, NULL
, NULL
);
2259 new_pid
= find_get_pid(tmp
);
2263 put_pid(xchg(&cad_pid
, new_pid
));
2267 #else /* CONFIG_PROC_FS */
2269 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
2270 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2275 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
2276 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2281 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
2282 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2287 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2288 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2293 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2294 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2299 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2300 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2305 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2306 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2311 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2312 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2317 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2319 void __user
*buffer
,
2320 size_t *lenp
, loff_t
*ppos
)
2326 #endif /* CONFIG_PROC_FS */
2329 #ifdef CONFIG_SYSCTL_SYSCALL
2331 * General sysctl support routines
2334 /* The generic string strategy routine: */
2335 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2336 void __user
*oldval
, size_t __user
*oldlenp
,
2337 void __user
*newval
, size_t newlen
)
2339 if (!table
->data
|| !table
->maxlen
)
2342 if (oldval
&& oldlenp
) {
2344 if (get_user(bufsize
, oldlenp
))
2347 size_t len
= strlen(table
->data
), copied
;
2349 /* This shouldn't trigger for a well-formed sysctl */
2350 if (len
> table
->maxlen
)
2351 len
= table
->maxlen
;
2353 /* Copy up to a max of bufsize-1 bytes of the string */
2354 copied
= (len
>= bufsize
) ? bufsize
- 1 : len
;
2356 if (copy_to_user(oldval
, table
->data
, copied
) ||
2357 put_user(0, (char __user
*)(oldval
+ copied
)))
2359 if (put_user(len
, oldlenp
))
2363 if (newval
&& newlen
) {
2364 size_t len
= newlen
;
2365 if (len
> table
->maxlen
)
2366 len
= table
->maxlen
;
2367 if(copy_from_user(table
->data
, newval
, len
))
2369 if (len
== table
->maxlen
)
2371 ((char *) table
->data
)[len
] = 0;
2377 * This function makes sure that all of the integers in the vector
2378 * are between the minimum and maximum values given in the arrays
2379 * table->extra1 and table->extra2, respectively.
2381 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2382 void __user
*oldval
, size_t __user
*oldlenp
,
2383 void __user
*newval
, size_t newlen
)
2386 if (newval
&& newlen
) {
2387 int __user
*vec
= (int __user
*) newval
;
2388 int *min
= (int *) table
->extra1
;
2389 int *max
= (int *) table
->extra2
;
2393 if (newlen
% sizeof(int) != 0)
2396 if (!table
->extra1
&& !table
->extra2
)
2399 if (newlen
> table
->maxlen
)
2400 newlen
= table
->maxlen
;
2401 length
= newlen
/ sizeof(int);
2403 for (i
= 0; i
< length
; i
++) {
2405 if (get_user(value
, vec
+ i
))
2407 if (min
&& value
< min
[i
])
2409 if (max
&& value
> max
[i
])
2416 /* Strategy function to convert jiffies to seconds */
2417 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2418 void __user
*oldval
, size_t __user
*oldlenp
,
2419 void __user
*newval
, size_t newlen
)
2421 if (oldval
&& oldlenp
) {
2424 if (get_user(olen
, oldlenp
))
2429 if (olen
< sizeof(int))
2432 val
= *(int *)(table
->data
) / HZ
;
2433 if (put_user(val
, (int __user
*)oldval
))
2435 if (put_user(sizeof(int), oldlenp
))
2439 if (newval
&& newlen
) {
2441 if (newlen
!= sizeof(int))
2443 if (get_user(new, (int __user
*)newval
))
2445 *(int *)(table
->data
) = new*HZ
;
2450 /* Strategy function to convert jiffies to seconds */
2451 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2452 void __user
*oldval
, size_t __user
*oldlenp
,
2453 void __user
*newval
, size_t newlen
)
2455 if (oldval
&& oldlenp
) {
2458 if (get_user(olen
, oldlenp
))
2463 if (olen
< sizeof(int))
2466 val
= jiffies_to_msecs(*(int *)(table
->data
));
2467 if (put_user(val
, (int __user
*)oldval
))
2469 if (put_user(sizeof(int), oldlenp
))
2473 if (newval
&& newlen
) {
2475 if (newlen
!= sizeof(int))
2477 if (get_user(new, (int __user
*)newval
))
2479 *(int *)(table
->data
) = msecs_to_jiffies(new);
2486 #else /* CONFIG_SYSCTL_SYSCALL */
2489 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
2491 static int msg_count
;
2492 struct __sysctl_args tmp
;
2493 int name
[CTL_MAXNAME
];
2496 /* Read in the sysctl name for better debug message logging */
2497 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
2499 if (tmp
.nlen
<= 0 || tmp
.nlen
>= CTL_MAXNAME
)
2501 for (i
= 0; i
< tmp
.nlen
; i
++)
2502 if (get_user(name
[i
], tmp
.name
+ i
))
2505 /* Ignore accesses to kernel.version */
2506 if ((tmp
.nlen
== 2) && (name
[0] == CTL_KERN
) && (name
[1] == KERN_VERSION
))
2509 if (msg_count
< 5) {
2512 "warning: process `%s' used the removed sysctl "
2513 "system call with ", current
->comm
);
2514 for (i
= 0; i
< tmp
.nlen
; i
++)
2515 printk("%d.", name
[i
]);
2522 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2523 void __user
*oldval
, size_t __user
*oldlenp
,
2524 void __user
*newval
, size_t newlen
)
2529 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2530 void __user
*oldval
, size_t __user
*oldlenp
,
2531 void __user
*newval
, size_t newlen
)
2536 int sysctl_jiffies(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_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2544 void __user
*oldval
, size_t __user
*oldlenp
,
2545 void __user
*newval
, size_t newlen
)
2550 #endif /* CONFIG_SYSCTL_SYSCALL */
2553 * No sense putting this after each symbol definition, twice,
2554 * exception granted :-)
2556 EXPORT_SYMBOL(proc_dointvec
);
2557 EXPORT_SYMBOL(proc_dointvec_jiffies
);
2558 EXPORT_SYMBOL(proc_dointvec_minmax
);
2559 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
2560 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
2561 EXPORT_SYMBOL(proc_dostring
);
2562 EXPORT_SYMBOL(proc_doulongvec_minmax
);
2563 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);
2564 EXPORT_SYMBOL(register_sysctl_table
);
2565 EXPORT_SYMBOL(sysctl_intvec
);
2566 EXPORT_SYMBOL(sysctl_jiffies
);
2567 EXPORT_SYMBOL(sysctl_ms_jiffies
);
2568 EXPORT_SYMBOL(sysctl_string
);
2569 EXPORT_SYMBOL(unregister_sysctl_table
);