2 * sysctl.c: General linux system control interface
4 * Begun 24 March 1995, Stephen Tweedie
5 * Added /proc support, Dec 1995
6 * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
7 * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
8 * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
9 * Dynamic registration fixes, Stephen Tweedie.
10 * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
11 * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
13 * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
14 * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
15 * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
17 * The list_for_each() macro wasn't appropriate for the sysctl loop.
18 * Removed it and replaced it with older style, 03/23/00, Bill Wendling
21 #include <linux/module.h>
23 #include <linux/swap.h>
24 #include <linux/slab.h>
25 #include <linux/sysctl.h>
26 #include <linux/proc_fs.h>
27 #include <linux/capability.h>
28 #include <linux/ctype.h>
29 #include <linux/utsname.h>
30 #include <linux/smp_lock.h>
32 #include <linux/init.h>
33 #include <linux/kernel.h>
34 #include <linux/kobject.h>
35 #include <linux/net.h>
36 #include <linux/sysrq.h>
37 #include <linux/highuid.h>
38 #include <linux/writeback.h>
39 #include <linux/hugetlb.h>
40 #include <linux/security.h>
41 #include <linux/initrd.h>
42 #include <linux/times.h>
43 #include <linux/limits.h>
44 #include <linux/dcache.h>
45 #include <linux/syscalls.h>
46 #include <linux/nfs_fs.h>
47 #include <linux/acpi.h>
48 #include <linux/reboot.h>
50 #include <asm/uaccess.h>
51 #include <asm/processor.h>
55 #include <asm/stacktrace.h>
58 #if defined(CONFIG_SYSCTL)
60 /* External variables not in a header file. */
62 extern int print_fatal_signals
;
63 extern int sysctl_overcommit_memory
;
64 extern int sysctl_overcommit_ratio
;
65 extern int sysctl_panic_on_oom
;
66 extern int max_threads
;
67 extern int core_uses_pid
;
68 extern int suid_dumpable
;
69 extern char core_pattern
[];
71 extern int min_free_kbytes
;
72 extern int printk_ratelimit_jiffies
;
73 extern int printk_ratelimit_burst
;
74 extern int pid_max_min
, pid_max_max
;
75 extern int sysctl_drop_caches
;
76 extern int percpu_pagelist_fraction
;
77 extern int compat_log
;
78 extern int maps_protect
;
79 extern int sysctl_stat_interval
;
80 extern int audit_argv_kb
;
82 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
83 static int maxolduid
= 65535;
85 static int min_percpu_pagelist_fract
= 8;
87 static int ngroups_max
= NGROUPS_MAX
;
90 extern char modprobe_path
[];
92 #ifdef CONFIG_CHR_DEV_SG
93 extern int sg_big_buff
;
97 extern char reboot_command
[];
98 extern int stop_a_enabled
;
99 extern int scons_pwroff
;
103 extern int pwrsw_enabled
;
104 extern int unaligned_enabled
;
108 #ifdef CONFIG_MATHEMU
109 extern int sysctl_ieee_emulation_warnings
;
111 extern int sysctl_userprocess_debug
;
112 extern int spin_retry
;
115 extern int sysctl_hz_timer
;
117 #ifdef CONFIG_BSD_PROCESS_ACCT
118 extern int acct_parm
[];
122 extern int no_unaligned_warning
;
125 #ifdef CONFIG_RT_MUTEXES
126 extern int max_lock_depth
;
129 #ifdef CONFIG_SYSCTL_SYSCALL
130 static int parse_table(int __user
*, int, void __user
*, size_t __user
*,
131 void __user
*, size_t, ctl_table
*);
135 #ifdef CONFIG_PROC_SYSCTL
136 static int proc_do_cad_pid(ctl_table
*table
, int write
, struct file
*filp
,
137 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
138 static int proc_dointvec_taint(ctl_table
*table
, int write
, struct file
*filp
,
139 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
142 static ctl_table root_table
[];
143 static struct ctl_table_header root_table_header
=
144 { root_table
, LIST_HEAD_INIT(root_table_header
.ctl_entry
) };
146 static ctl_table kern_table
[];
147 static ctl_table vm_table
[];
148 static ctl_table fs_table
[];
149 static ctl_table debug_table
[];
150 static ctl_table dev_table
[];
151 extern ctl_table random_table
[];
152 #ifdef CONFIG_UNIX98_PTYS
153 extern ctl_table pty_table
[];
155 #ifdef CONFIG_INOTIFY_USER
156 extern ctl_table inotify_table
[];
159 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
160 int sysctl_legacy_va_layout
;
163 extern int prove_locking
;
164 extern int lock_stat
;
166 /* The default sysctl tables: */
168 static ctl_table root_table
[] = {
170 .ctl_name
= CTL_KERN
,
171 .procname
= "kernel",
196 .ctl_name
= CTL_DEBUG
,
199 .child
= debug_table
,
208 * NOTE: do not add new entries to this table unless you have read
209 * Documentation/sysctl/ctl_unnumbered.txt
214 #ifdef CONFIG_SCHED_DEBUG
215 static unsigned long min_sched_granularity_ns
= 100000; /* 100 usecs */
216 static unsigned long max_sched_granularity_ns
= 1000000000; /* 1 second */
217 static unsigned long min_wakeup_granularity_ns
; /* 0 usecs */
218 static unsigned long max_wakeup_granularity_ns
= 1000000000; /* 1 second */
221 static ctl_table kern_table
[] = {
222 #ifdef CONFIG_SCHED_DEBUG
224 .ctl_name
= CTL_UNNUMBERED
,
225 .procname
= "sched_nr_latency",
226 .data
= &sysctl_sched_nr_latency
,
227 .maxlen
= sizeof(unsigned int),
229 .proc_handler
= &proc_dointvec
,
232 .ctl_name
= CTL_UNNUMBERED
,
233 .procname
= "sched_latency_ns",
234 .data
= &sysctl_sched_latency
,
235 .maxlen
= sizeof(unsigned int),
237 .proc_handler
= &proc_dointvec_minmax
,
238 .strategy
= &sysctl_intvec
,
239 .extra1
= &min_sched_granularity_ns
,
240 .extra2
= &max_sched_granularity_ns
,
243 .ctl_name
= CTL_UNNUMBERED
,
244 .procname
= "sched_wakeup_granularity_ns",
245 .data
= &sysctl_sched_wakeup_granularity
,
246 .maxlen
= sizeof(unsigned int),
248 .proc_handler
= &proc_dointvec_minmax
,
249 .strategy
= &sysctl_intvec
,
250 .extra1
= &min_wakeup_granularity_ns
,
251 .extra2
= &max_wakeup_granularity_ns
,
254 .ctl_name
= CTL_UNNUMBERED
,
255 .procname
= "sched_batch_wakeup_granularity_ns",
256 .data
= &sysctl_sched_batch_wakeup_granularity
,
257 .maxlen
= sizeof(unsigned int),
259 .proc_handler
= &proc_dointvec_minmax
,
260 .strategy
= &sysctl_intvec
,
261 .extra1
= &min_wakeup_granularity_ns
,
262 .extra2
= &max_wakeup_granularity_ns
,
265 .ctl_name
= CTL_UNNUMBERED
,
266 .procname
= "sched_child_runs_first",
267 .data
= &sysctl_sched_child_runs_first
,
268 .maxlen
= sizeof(unsigned int),
270 .proc_handler
= &proc_dointvec
,
273 .ctl_name
= CTL_UNNUMBERED
,
274 .procname
= "sched_features",
275 .data
= &sysctl_sched_features
,
276 .maxlen
= sizeof(unsigned int),
278 .proc_handler
= &proc_dointvec
,
281 .ctl_name
= CTL_UNNUMBERED
,
282 .procname
= "sched_migration_cost",
283 .data
= &sysctl_sched_migration_cost
,
284 .maxlen
= sizeof(unsigned int),
286 .proc_handler
= &proc_dointvec
,
290 .ctl_name
= CTL_UNNUMBERED
,
291 .procname
= "sched_compat_yield",
292 .data
= &sysctl_sched_compat_yield
,
293 .maxlen
= sizeof(unsigned int),
295 .proc_handler
= &proc_dointvec
,
297 #ifdef CONFIG_PROVE_LOCKING
299 .ctl_name
= CTL_UNNUMBERED
,
300 .procname
= "prove_locking",
301 .data
= &prove_locking
,
302 .maxlen
= sizeof(int),
304 .proc_handler
= &proc_dointvec
,
307 #ifdef CONFIG_LOCK_STAT
309 .ctl_name
= CTL_UNNUMBERED
,
310 .procname
= "lock_stat",
312 .maxlen
= sizeof(int),
314 .proc_handler
= &proc_dointvec
,
318 .ctl_name
= KERN_PANIC
,
320 .data
= &panic_timeout
,
321 .maxlen
= sizeof(int),
323 .proc_handler
= &proc_dointvec
,
326 .ctl_name
= KERN_CORE_USES_PID
,
327 .procname
= "core_uses_pid",
328 .data
= &core_uses_pid
,
329 .maxlen
= sizeof(int),
331 .proc_handler
= &proc_dointvec
,
333 #ifdef CONFIG_AUDITSYSCALL
335 .ctl_name
= CTL_UNNUMBERED
,
336 .procname
= "audit_argv_kb",
337 .data
= &audit_argv_kb
,
338 .maxlen
= sizeof(int),
340 .proc_handler
= &proc_dointvec
,
344 .ctl_name
= KERN_CORE_PATTERN
,
345 .procname
= "core_pattern",
346 .data
= core_pattern
,
347 .maxlen
= CORENAME_MAX_SIZE
,
349 .proc_handler
= &proc_dostring
,
350 .strategy
= &sysctl_string
,
352 #ifdef CONFIG_PROC_SYSCTL
354 .ctl_name
= KERN_TAINTED
,
355 .procname
= "tainted",
357 .maxlen
= sizeof(int),
359 .proc_handler
= &proc_dointvec_taint
,
363 .ctl_name
= KERN_CAP_BSET
,
364 .procname
= "cap-bound",
366 .maxlen
= sizeof(kernel_cap_t
),
368 .proc_handler
= &proc_dointvec_bset
,
370 #ifdef CONFIG_BLK_DEV_INITRD
372 .ctl_name
= KERN_REALROOTDEV
,
373 .procname
= "real-root-dev",
374 .data
= &real_root_dev
,
375 .maxlen
= sizeof(int),
377 .proc_handler
= &proc_dointvec
,
381 .ctl_name
= CTL_UNNUMBERED
,
382 .procname
= "print-fatal-signals",
383 .data
= &print_fatal_signals
,
384 .maxlen
= sizeof(int),
386 .proc_handler
= &proc_dointvec
,
390 .ctl_name
= KERN_SPARC_REBOOT
,
391 .procname
= "reboot-cmd",
392 .data
= reboot_command
,
395 .proc_handler
= &proc_dostring
,
396 .strategy
= &sysctl_string
,
399 .ctl_name
= KERN_SPARC_STOP_A
,
400 .procname
= "stop-a",
401 .data
= &stop_a_enabled
,
402 .maxlen
= sizeof (int),
404 .proc_handler
= &proc_dointvec
,
407 .ctl_name
= KERN_SPARC_SCONS_PWROFF
,
408 .procname
= "scons-poweroff",
409 .data
= &scons_pwroff
,
410 .maxlen
= sizeof (int),
412 .proc_handler
= &proc_dointvec
,
417 .ctl_name
= KERN_HPPA_PWRSW
,
418 .procname
= "soft-power",
419 .data
= &pwrsw_enabled
,
420 .maxlen
= sizeof (int),
422 .proc_handler
= &proc_dointvec
,
425 .ctl_name
= KERN_HPPA_UNALIGNED
,
426 .procname
= "unaligned-trap",
427 .data
= &unaligned_enabled
,
428 .maxlen
= sizeof (int),
430 .proc_handler
= &proc_dointvec
,
434 .ctl_name
= KERN_CTLALTDEL
,
435 .procname
= "ctrl-alt-del",
437 .maxlen
= sizeof(int),
439 .proc_handler
= &proc_dointvec
,
442 .ctl_name
= KERN_PRINTK
,
443 .procname
= "printk",
444 .data
= &console_loglevel
,
445 .maxlen
= 4*sizeof(int),
447 .proc_handler
= &proc_dointvec
,
451 .ctl_name
= KERN_MODPROBE
,
452 .procname
= "modprobe",
453 .data
= &modprobe_path
,
454 .maxlen
= KMOD_PATH_LEN
,
456 .proc_handler
= &proc_dostring
,
457 .strategy
= &sysctl_string
,
460 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
462 .ctl_name
= KERN_HOTPLUG
,
463 .procname
= "hotplug",
464 .data
= &uevent_helper
,
465 .maxlen
= UEVENT_HELPER_PATH_LEN
,
467 .proc_handler
= &proc_dostring
,
468 .strategy
= &sysctl_string
,
471 #ifdef CONFIG_CHR_DEV_SG
473 .ctl_name
= KERN_SG_BIG_BUFF
,
474 .procname
= "sg-big-buff",
475 .data
= &sg_big_buff
,
476 .maxlen
= sizeof (int),
478 .proc_handler
= &proc_dointvec
,
481 #ifdef CONFIG_BSD_PROCESS_ACCT
483 .ctl_name
= KERN_ACCT
,
486 .maxlen
= 3*sizeof(int),
488 .proc_handler
= &proc_dointvec
,
491 #ifdef CONFIG_MAGIC_SYSRQ
493 .ctl_name
= KERN_SYSRQ
,
495 .data
= &__sysrq_enabled
,
496 .maxlen
= sizeof (int),
498 .proc_handler
= &proc_dointvec
,
501 #ifdef CONFIG_PROC_SYSCTL
503 .ctl_name
= KERN_CADPID
,
504 .procname
= "cad_pid",
506 .maxlen
= sizeof (int),
508 .proc_handler
= &proc_do_cad_pid
,
512 .ctl_name
= KERN_MAX_THREADS
,
513 .procname
= "threads-max",
514 .data
= &max_threads
,
515 .maxlen
= sizeof(int),
517 .proc_handler
= &proc_dointvec
,
520 .ctl_name
= KERN_RANDOM
,
521 .procname
= "random",
523 .child
= random_table
,
525 #ifdef CONFIG_UNIX98_PTYS
527 .ctl_name
= KERN_PTY
,
534 .ctl_name
= KERN_OVERFLOWUID
,
535 .procname
= "overflowuid",
536 .data
= &overflowuid
,
537 .maxlen
= sizeof(int),
539 .proc_handler
= &proc_dointvec_minmax
,
540 .strategy
= &sysctl_intvec
,
541 .extra1
= &minolduid
,
542 .extra2
= &maxolduid
,
545 .ctl_name
= KERN_OVERFLOWGID
,
546 .procname
= "overflowgid",
547 .data
= &overflowgid
,
548 .maxlen
= sizeof(int),
550 .proc_handler
= &proc_dointvec_minmax
,
551 .strategy
= &sysctl_intvec
,
552 .extra1
= &minolduid
,
553 .extra2
= &maxolduid
,
556 #ifdef CONFIG_MATHEMU
558 .ctl_name
= KERN_IEEE_EMULATION_WARNINGS
,
559 .procname
= "ieee_emulation_warnings",
560 .data
= &sysctl_ieee_emulation_warnings
,
561 .maxlen
= sizeof(int),
563 .proc_handler
= &proc_dointvec
,
566 #ifdef CONFIG_NO_IDLE_HZ
568 .ctl_name
= KERN_HZ_TIMER
,
569 .procname
= "hz_timer",
570 .data
= &sysctl_hz_timer
,
571 .maxlen
= sizeof(int),
573 .proc_handler
= &proc_dointvec
,
577 .ctl_name
= KERN_S390_USER_DEBUG_LOGGING
,
578 .procname
= "userprocess_debug",
579 .data
= &sysctl_userprocess_debug
,
580 .maxlen
= sizeof(int),
582 .proc_handler
= &proc_dointvec
,
586 .ctl_name
= KERN_PIDMAX
,
587 .procname
= "pid_max",
589 .maxlen
= sizeof (int),
591 .proc_handler
= &proc_dointvec_minmax
,
592 .strategy
= sysctl_intvec
,
593 .extra1
= &pid_max_min
,
594 .extra2
= &pid_max_max
,
597 .ctl_name
= KERN_PANIC_ON_OOPS
,
598 .procname
= "panic_on_oops",
599 .data
= &panic_on_oops
,
600 .maxlen
= sizeof(int),
602 .proc_handler
= &proc_dointvec
,
605 .ctl_name
= KERN_PRINTK_RATELIMIT
,
606 .procname
= "printk_ratelimit",
607 .data
= &printk_ratelimit_jiffies
,
608 .maxlen
= sizeof(int),
610 .proc_handler
= &proc_dointvec_jiffies
,
611 .strategy
= &sysctl_jiffies
,
614 .ctl_name
= KERN_PRINTK_RATELIMIT_BURST
,
615 .procname
= "printk_ratelimit_burst",
616 .data
= &printk_ratelimit_burst
,
617 .maxlen
= sizeof(int),
619 .proc_handler
= &proc_dointvec
,
622 .ctl_name
= KERN_NGROUPS_MAX
,
623 .procname
= "ngroups_max",
624 .data
= &ngroups_max
,
625 .maxlen
= sizeof (int),
627 .proc_handler
= &proc_dointvec
,
629 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
631 .ctl_name
= KERN_UNKNOWN_NMI_PANIC
,
632 .procname
= "unknown_nmi_panic",
633 .data
= &unknown_nmi_panic
,
634 .maxlen
= sizeof (int),
636 .proc_handler
= &proc_dointvec
,
639 .ctl_name
= KERN_NMI_WATCHDOG
,
640 .procname
= "nmi_watchdog",
641 .data
= &nmi_watchdog_enabled
,
642 .maxlen
= sizeof (int),
644 .proc_handler
= &proc_nmi_enabled
,
647 #if defined(CONFIG_X86)
649 .ctl_name
= KERN_PANIC_ON_NMI
,
650 .procname
= "panic_on_unrecovered_nmi",
651 .data
= &panic_on_unrecovered_nmi
,
652 .maxlen
= sizeof(int),
654 .proc_handler
= &proc_dointvec
,
657 .ctl_name
= KERN_BOOTLOADER_TYPE
,
658 .procname
= "bootloader_type",
659 .data
= &bootloader_type
,
660 .maxlen
= sizeof (int),
662 .proc_handler
= &proc_dointvec
,
665 .ctl_name
= CTL_UNNUMBERED
,
666 .procname
= "kstack_depth_to_print",
667 .data
= &kstack_depth_to_print
,
668 .maxlen
= sizeof(int),
670 .proc_handler
= &proc_dointvec
,
673 #if defined(CONFIG_MMU)
675 .ctl_name
= KERN_RANDOMIZE
,
676 .procname
= "randomize_va_space",
677 .data
= &randomize_va_space
,
678 .maxlen
= sizeof(int),
680 .proc_handler
= &proc_dointvec
,
683 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
685 .ctl_name
= KERN_SPIN_RETRY
,
686 .procname
= "spin_retry",
688 .maxlen
= sizeof (int),
690 .proc_handler
= &proc_dointvec
,
693 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
695 .ctl_name
= KERN_ACPI_VIDEO_FLAGS
,
696 .procname
= "acpi_video_flags",
697 .data
= &acpi_realmode_flags
,
698 .maxlen
= sizeof (unsigned long),
700 .proc_handler
= &proc_doulongvec_minmax
,
705 .ctl_name
= KERN_IA64_UNALIGNED
,
706 .procname
= "ignore-unaligned-usertrap",
707 .data
= &no_unaligned_warning
,
708 .maxlen
= sizeof (int),
710 .proc_handler
= &proc_dointvec
,
715 .ctl_name
= KERN_COMPAT_LOG
,
716 .procname
= "compat-log",
718 .maxlen
= sizeof (int),
720 .proc_handler
= &proc_dointvec
,
723 #ifdef CONFIG_RT_MUTEXES
725 .ctl_name
= KERN_MAX_LOCK_DEPTH
,
726 .procname
= "max_lock_depth",
727 .data
= &max_lock_depth
,
728 .maxlen
= sizeof(int),
730 .proc_handler
= &proc_dointvec
,
733 #ifdef CONFIG_PROC_FS
735 .ctl_name
= CTL_UNNUMBERED
,
736 .procname
= "maps_protect",
737 .data
= &maps_protect
,
738 .maxlen
= sizeof(int),
740 .proc_handler
= &proc_dointvec
,
744 .ctl_name
= CTL_UNNUMBERED
,
745 .procname
= "poweroff_cmd",
746 .data
= &poweroff_cmd
,
747 .maxlen
= POWEROFF_CMD_PATH_LEN
,
749 .proc_handler
= &proc_dostring
,
750 .strategy
= &sysctl_string
,
753 * NOTE: do not add new entries to this table unless you have read
754 * Documentation/sysctl/ctl_unnumbered.txt
759 /* Constants for minimum and maximum testing in vm_table.
760 We use these as one-element integer vectors. */
763 static int one_hundred
= 100;
766 static ctl_table vm_table
[] = {
768 .ctl_name
= VM_OVERCOMMIT_MEMORY
,
769 .procname
= "overcommit_memory",
770 .data
= &sysctl_overcommit_memory
,
771 .maxlen
= sizeof(sysctl_overcommit_memory
),
773 .proc_handler
= &proc_dointvec
,
776 .ctl_name
= VM_PANIC_ON_OOM
,
777 .procname
= "panic_on_oom",
778 .data
= &sysctl_panic_on_oom
,
779 .maxlen
= sizeof(sysctl_panic_on_oom
),
781 .proc_handler
= &proc_dointvec
,
784 .ctl_name
= VM_OVERCOMMIT_RATIO
,
785 .procname
= "overcommit_ratio",
786 .data
= &sysctl_overcommit_ratio
,
787 .maxlen
= sizeof(sysctl_overcommit_ratio
),
789 .proc_handler
= &proc_dointvec
,
792 .ctl_name
= VM_PAGE_CLUSTER
,
793 .procname
= "page-cluster",
794 .data
= &page_cluster
,
795 .maxlen
= sizeof(int),
797 .proc_handler
= &proc_dointvec
,
800 .ctl_name
= VM_DIRTY_BACKGROUND
,
801 .procname
= "dirty_background_ratio",
802 .data
= &dirty_background_ratio
,
803 .maxlen
= sizeof(dirty_background_ratio
),
805 .proc_handler
= &proc_dointvec_minmax
,
806 .strategy
= &sysctl_intvec
,
808 .extra2
= &one_hundred
,
811 .ctl_name
= VM_DIRTY_RATIO
,
812 .procname
= "dirty_ratio",
813 .data
= &vm_dirty_ratio
,
814 .maxlen
= sizeof(vm_dirty_ratio
),
816 .proc_handler
= &proc_dointvec_minmax
,
817 .strategy
= &sysctl_intvec
,
819 .extra2
= &one_hundred
,
822 .ctl_name
= VM_DIRTY_WB_CS
,
823 .procname
= "dirty_writeback_centisecs",
824 .data
= &dirty_writeback_interval
,
825 .maxlen
= sizeof(dirty_writeback_interval
),
827 .proc_handler
= &dirty_writeback_centisecs_handler
,
830 .ctl_name
= VM_DIRTY_EXPIRE_CS
,
831 .procname
= "dirty_expire_centisecs",
832 .data
= &dirty_expire_interval
,
833 .maxlen
= sizeof(dirty_expire_interval
),
835 .proc_handler
= &proc_dointvec_userhz_jiffies
,
838 .ctl_name
= VM_NR_PDFLUSH_THREADS
,
839 .procname
= "nr_pdflush_threads",
840 .data
= &nr_pdflush_threads
,
841 .maxlen
= sizeof nr_pdflush_threads
,
842 .mode
= 0444 /* read-only*/,
843 .proc_handler
= &proc_dointvec
,
846 .ctl_name
= VM_SWAPPINESS
,
847 .procname
= "swappiness",
848 .data
= &vm_swappiness
,
849 .maxlen
= sizeof(vm_swappiness
),
851 .proc_handler
= &proc_dointvec_minmax
,
852 .strategy
= &sysctl_intvec
,
854 .extra2
= &one_hundred
,
856 #ifdef CONFIG_HUGETLB_PAGE
858 .ctl_name
= VM_HUGETLB_PAGES
,
859 .procname
= "nr_hugepages",
860 .data
= &max_huge_pages
,
861 .maxlen
= sizeof(unsigned long),
863 .proc_handler
= &hugetlb_sysctl_handler
,
864 .extra1
= (void *)&hugetlb_zero
,
865 .extra2
= (void *)&hugetlb_infinity
,
868 .ctl_name
= VM_HUGETLB_GROUP
,
869 .procname
= "hugetlb_shm_group",
870 .data
= &sysctl_hugetlb_shm_group
,
871 .maxlen
= sizeof(gid_t
),
873 .proc_handler
= &proc_dointvec
,
876 .ctl_name
= CTL_UNNUMBERED
,
877 .procname
= "hugepages_treat_as_movable",
878 .data
= &hugepages_treat_as_movable
,
879 .maxlen
= sizeof(int),
881 .proc_handler
= &hugetlb_treat_movable_handler
,
884 .ctl_name
= CTL_UNNUMBERED
,
885 .procname
= "hugetlb_dynamic_pool",
886 .data
= &hugetlb_dynamic_pool
,
887 .maxlen
= sizeof(hugetlb_dynamic_pool
),
889 .proc_handler
= &proc_dointvec
,
893 .ctl_name
= VM_LOWMEM_RESERVE_RATIO
,
894 .procname
= "lowmem_reserve_ratio",
895 .data
= &sysctl_lowmem_reserve_ratio
,
896 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
898 .proc_handler
= &lowmem_reserve_ratio_sysctl_handler
,
899 .strategy
= &sysctl_intvec
,
902 .ctl_name
= VM_DROP_PAGECACHE
,
903 .procname
= "drop_caches",
904 .data
= &sysctl_drop_caches
,
905 .maxlen
= sizeof(int),
907 .proc_handler
= drop_caches_sysctl_handler
,
908 .strategy
= &sysctl_intvec
,
911 .ctl_name
= VM_MIN_FREE_KBYTES
,
912 .procname
= "min_free_kbytes",
913 .data
= &min_free_kbytes
,
914 .maxlen
= sizeof(min_free_kbytes
),
916 .proc_handler
= &min_free_kbytes_sysctl_handler
,
917 .strategy
= &sysctl_intvec
,
921 .ctl_name
= VM_PERCPU_PAGELIST_FRACTION
,
922 .procname
= "percpu_pagelist_fraction",
923 .data
= &percpu_pagelist_fraction
,
924 .maxlen
= sizeof(percpu_pagelist_fraction
),
926 .proc_handler
= &percpu_pagelist_fraction_sysctl_handler
,
927 .strategy
= &sysctl_intvec
,
928 .extra1
= &min_percpu_pagelist_fract
,
932 .ctl_name
= VM_MAX_MAP_COUNT
,
933 .procname
= "max_map_count",
934 .data
= &sysctl_max_map_count
,
935 .maxlen
= sizeof(sysctl_max_map_count
),
937 .proc_handler
= &proc_dointvec
941 .ctl_name
= VM_LAPTOP_MODE
,
942 .procname
= "laptop_mode",
943 .data
= &laptop_mode
,
944 .maxlen
= sizeof(laptop_mode
),
946 .proc_handler
= &proc_dointvec_jiffies
,
947 .strategy
= &sysctl_jiffies
,
950 .ctl_name
= VM_BLOCK_DUMP
,
951 .procname
= "block_dump",
953 .maxlen
= sizeof(block_dump
),
955 .proc_handler
= &proc_dointvec
,
956 .strategy
= &sysctl_intvec
,
960 .ctl_name
= VM_VFS_CACHE_PRESSURE
,
961 .procname
= "vfs_cache_pressure",
962 .data
= &sysctl_vfs_cache_pressure
,
963 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
965 .proc_handler
= &proc_dointvec
,
966 .strategy
= &sysctl_intvec
,
969 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
971 .ctl_name
= VM_LEGACY_VA_LAYOUT
,
972 .procname
= "legacy_va_layout",
973 .data
= &sysctl_legacy_va_layout
,
974 .maxlen
= sizeof(sysctl_legacy_va_layout
),
976 .proc_handler
= &proc_dointvec
,
977 .strategy
= &sysctl_intvec
,
983 .ctl_name
= VM_ZONE_RECLAIM_MODE
,
984 .procname
= "zone_reclaim_mode",
985 .data
= &zone_reclaim_mode
,
986 .maxlen
= sizeof(zone_reclaim_mode
),
988 .proc_handler
= &proc_dointvec
,
989 .strategy
= &sysctl_intvec
,
993 .ctl_name
= VM_MIN_UNMAPPED
,
994 .procname
= "min_unmapped_ratio",
995 .data
= &sysctl_min_unmapped_ratio
,
996 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
998 .proc_handler
= &sysctl_min_unmapped_ratio_sysctl_handler
,
999 .strategy
= &sysctl_intvec
,
1001 .extra2
= &one_hundred
,
1004 .ctl_name
= VM_MIN_SLAB
,
1005 .procname
= "min_slab_ratio",
1006 .data
= &sysctl_min_slab_ratio
,
1007 .maxlen
= sizeof(sysctl_min_slab_ratio
),
1009 .proc_handler
= &sysctl_min_slab_ratio_sysctl_handler
,
1010 .strategy
= &sysctl_intvec
,
1012 .extra2
= &one_hundred
,
1017 .ctl_name
= CTL_UNNUMBERED
,
1018 .procname
= "stat_interval",
1019 .data
= &sysctl_stat_interval
,
1020 .maxlen
= sizeof(sysctl_stat_interval
),
1022 .proc_handler
= &proc_dointvec_jiffies
,
1023 .strategy
= &sysctl_jiffies
,
1026 #ifdef CONFIG_SECURITY
1028 .ctl_name
= CTL_UNNUMBERED
,
1029 .procname
= "mmap_min_addr",
1030 .data
= &mmap_min_addr
,
1031 .maxlen
= sizeof(unsigned long),
1033 .proc_handler
= &proc_doulongvec_minmax
,
1038 .ctl_name
= CTL_UNNUMBERED
,
1039 .procname
= "numa_zonelist_order",
1040 .data
= &numa_zonelist_order
,
1041 .maxlen
= NUMA_ZONELIST_ORDER_LEN
,
1043 .proc_handler
= &numa_zonelist_order_handler
,
1044 .strategy
= &sysctl_string
,
1047 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1048 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1050 .ctl_name
= VM_VDSO_ENABLED
,
1051 .procname
= "vdso_enabled",
1052 .data
= &vdso_enabled
,
1053 .maxlen
= sizeof(vdso_enabled
),
1055 .proc_handler
= &proc_dointvec
,
1056 .strategy
= &sysctl_intvec
,
1061 * NOTE: do not add new entries to this table unless you have read
1062 * Documentation/sysctl/ctl_unnumbered.txt
1067 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1068 static ctl_table binfmt_misc_table
[] = {
1073 static ctl_table fs_table
[] = {
1075 .ctl_name
= FS_NRINODE
,
1076 .procname
= "inode-nr",
1077 .data
= &inodes_stat
,
1078 .maxlen
= 2*sizeof(int),
1080 .proc_handler
= &proc_dointvec
,
1083 .ctl_name
= FS_STATINODE
,
1084 .procname
= "inode-state",
1085 .data
= &inodes_stat
,
1086 .maxlen
= 7*sizeof(int),
1088 .proc_handler
= &proc_dointvec
,
1091 .ctl_name
= FS_NRFILE
,
1092 .procname
= "file-nr",
1093 .data
= &files_stat
,
1094 .maxlen
= 3*sizeof(int),
1096 .proc_handler
= &proc_nr_files
,
1099 .ctl_name
= FS_MAXFILE
,
1100 .procname
= "file-max",
1101 .data
= &files_stat
.max_files
,
1102 .maxlen
= sizeof(int),
1104 .proc_handler
= &proc_dointvec
,
1107 .ctl_name
= FS_DENTRY
,
1108 .procname
= "dentry-state",
1109 .data
= &dentry_stat
,
1110 .maxlen
= 6*sizeof(int),
1112 .proc_handler
= &proc_dointvec
,
1115 .ctl_name
= FS_OVERFLOWUID
,
1116 .procname
= "overflowuid",
1117 .data
= &fs_overflowuid
,
1118 .maxlen
= sizeof(int),
1120 .proc_handler
= &proc_dointvec_minmax
,
1121 .strategy
= &sysctl_intvec
,
1122 .extra1
= &minolduid
,
1123 .extra2
= &maxolduid
,
1126 .ctl_name
= FS_OVERFLOWGID
,
1127 .procname
= "overflowgid",
1128 .data
= &fs_overflowgid
,
1129 .maxlen
= sizeof(int),
1131 .proc_handler
= &proc_dointvec_minmax
,
1132 .strategy
= &sysctl_intvec
,
1133 .extra1
= &minolduid
,
1134 .extra2
= &maxolduid
,
1137 .ctl_name
= FS_LEASES
,
1138 .procname
= "leases-enable",
1139 .data
= &leases_enable
,
1140 .maxlen
= sizeof(int),
1142 .proc_handler
= &proc_dointvec
,
1144 #ifdef CONFIG_DNOTIFY
1146 .ctl_name
= FS_DIR_NOTIFY
,
1147 .procname
= "dir-notify-enable",
1148 .data
= &dir_notify_enable
,
1149 .maxlen
= sizeof(int),
1151 .proc_handler
= &proc_dointvec
,
1156 .ctl_name
= FS_LEASE_TIME
,
1157 .procname
= "lease-break-time",
1158 .data
= &lease_break_time
,
1159 .maxlen
= sizeof(int),
1161 .proc_handler
= &proc_dointvec_minmax
,
1162 .strategy
= &sysctl_intvec
,
1167 .ctl_name
= FS_AIO_NR
,
1168 .procname
= "aio-nr",
1170 .maxlen
= sizeof(aio_nr
),
1172 .proc_handler
= &proc_doulongvec_minmax
,
1175 .ctl_name
= FS_AIO_MAX_NR
,
1176 .procname
= "aio-max-nr",
1177 .data
= &aio_max_nr
,
1178 .maxlen
= sizeof(aio_max_nr
),
1180 .proc_handler
= &proc_doulongvec_minmax
,
1182 #ifdef CONFIG_INOTIFY_USER
1184 .ctl_name
= FS_INOTIFY
,
1185 .procname
= "inotify",
1187 .child
= inotify_table
,
1192 .ctl_name
= KERN_SETUID_DUMPABLE
,
1193 .procname
= "suid_dumpable",
1194 .data
= &suid_dumpable
,
1195 .maxlen
= sizeof(int),
1197 .proc_handler
= &proc_dointvec
,
1199 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1201 .ctl_name
= CTL_UNNUMBERED
,
1202 .procname
= "binfmt_misc",
1204 .child
= binfmt_misc_table
,
1208 * NOTE: do not add new entries to this table unless you have read
1209 * Documentation/sysctl/ctl_unnumbered.txt
1214 static ctl_table debug_table
[] = {
1215 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1217 .ctl_name
= CTL_UNNUMBERED
,
1218 .procname
= "exception-trace",
1219 .data
= &show_unhandled_signals
,
1220 .maxlen
= sizeof(int),
1222 .proc_handler
= proc_dointvec
1228 static ctl_table dev_table
[] = {
1232 static DEFINE_SPINLOCK(sysctl_lock
);
1234 /* called under sysctl_lock */
1235 static int use_table(struct ctl_table_header
*p
)
1237 if (unlikely(p
->unregistering
))
1243 /* called under sysctl_lock */
1244 static void unuse_table(struct ctl_table_header
*p
)
1247 if (unlikely(p
->unregistering
))
1248 complete(p
->unregistering
);
1251 /* called under sysctl_lock, will reacquire if has to wait */
1252 static void start_unregistering(struct ctl_table_header
*p
)
1255 * if p->used is 0, nobody will ever touch that entry again;
1256 * we'll eliminate all paths to it before dropping sysctl_lock
1258 if (unlikely(p
->used
)) {
1259 struct completion wait
;
1260 init_completion(&wait
);
1261 p
->unregistering
= &wait
;
1262 spin_unlock(&sysctl_lock
);
1263 wait_for_completion(&wait
);
1264 spin_lock(&sysctl_lock
);
1267 * do not remove from the list until nobody holds it; walking the
1268 * list in do_sysctl() relies on that.
1270 list_del_init(&p
->ctl_entry
);
1273 void sysctl_head_finish(struct ctl_table_header
*head
)
1277 spin_lock(&sysctl_lock
);
1279 spin_unlock(&sysctl_lock
);
1282 struct ctl_table_header
*sysctl_head_next(struct ctl_table_header
*prev
)
1284 struct ctl_table_header
*head
;
1285 struct list_head
*tmp
;
1286 spin_lock(&sysctl_lock
);
1288 tmp
= &prev
->ctl_entry
;
1292 tmp
= &root_table_header
.ctl_entry
;
1294 head
= list_entry(tmp
, struct ctl_table_header
, ctl_entry
);
1296 if (!use_table(head
))
1298 spin_unlock(&sysctl_lock
);
1302 if (tmp
== &root_table_header
.ctl_entry
)
1305 spin_unlock(&sysctl_lock
);
1309 #ifdef CONFIG_SYSCTL_SYSCALL
1310 int do_sysctl(int __user
*name
, int nlen
, void __user
*oldval
, size_t __user
*oldlenp
,
1311 void __user
*newval
, size_t newlen
)
1313 struct ctl_table_header
*head
;
1314 int error
= -ENOTDIR
;
1316 if (nlen
<= 0 || nlen
>= CTL_MAXNAME
)
1320 if (!oldlenp
|| get_user(old_len
, oldlenp
))
1324 for (head
= sysctl_head_next(NULL
); head
;
1325 head
= sysctl_head_next(head
)) {
1326 error
= parse_table(name
, nlen
, oldval
, oldlenp
,
1327 newval
, newlen
, head
->ctl_table
);
1328 if (error
!= -ENOTDIR
) {
1329 sysctl_head_finish(head
);
1336 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
1338 struct __sysctl_args tmp
;
1341 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
1345 error
= do_sysctl(tmp
.name
, tmp
.nlen
, tmp
.oldval
, tmp
.oldlenp
,
1346 tmp
.newval
, tmp
.newlen
);
1350 #endif /* CONFIG_SYSCTL_SYSCALL */
1353 * sysctl_perm does NOT grant the superuser all rights automatically, because
1354 * some sysctl variables are readonly even to root.
1357 static int test_perm(int mode
, int op
)
1361 else if (in_egroup_p(0))
1363 if ((mode
& op
& 0007) == op
)
1368 int sysctl_perm(ctl_table
*table
, int op
)
1371 error
= security_sysctl(table
, op
);
1374 return test_perm(table
->mode
, op
);
1377 #ifdef CONFIG_SYSCTL_SYSCALL
1378 static int parse_table(int __user
*name
, int nlen
,
1379 void __user
*oldval
, size_t __user
*oldlenp
,
1380 void __user
*newval
, size_t newlen
,
1387 if (get_user(n
, name
))
1389 for ( ; table
->ctl_name
|| table
->procname
; table
++) {
1390 if (!table
->ctl_name
)
1392 if (n
== table
->ctl_name
) {
1395 if (sysctl_perm(table
, 001))
1399 table
= table
->child
;
1402 error
= do_sysctl_strategy(table
, name
, nlen
,
1411 /* Perform the actual read/write of a sysctl table entry. */
1412 int do_sysctl_strategy (ctl_table
*table
,
1413 int __user
*name
, int nlen
,
1414 void __user
*oldval
, size_t __user
*oldlenp
,
1415 void __user
*newval
, size_t newlen
)
1424 if (sysctl_perm(table
, op
))
1427 if (table
->strategy
) {
1428 rc
= table
->strategy(table
, name
, nlen
, oldval
, oldlenp
,
1436 /* If there is no strategy routine, or if the strategy returns
1437 * zero, proceed with automatic r/w */
1438 if (table
->data
&& table
->maxlen
) {
1439 if (oldval
&& oldlenp
) {
1440 if (get_user(len
, oldlenp
))
1443 if (len
> table
->maxlen
)
1444 len
= table
->maxlen
;
1445 if(copy_to_user(oldval
, table
->data
, len
))
1447 if(put_user(len
, oldlenp
))
1451 if (newval
&& newlen
) {
1453 if (len
> table
->maxlen
)
1454 len
= table
->maxlen
;
1455 if(copy_from_user(table
->data
, newval
, len
))
1461 #endif /* CONFIG_SYSCTL_SYSCALL */
1463 static void sysctl_set_parent(struct ctl_table
*parent
, struct ctl_table
*table
)
1465 for (; table
->ctl_name
|| table
->procname
; table
++) {
1466 table
->parent
= parent
;
1468 sysctl_set_parent(table
, table
->child
);
1472 static __init
int sysctl_init(void)
1474 sysctl_set_parent(NULL
, root_table
);
1478 core_initcall(sysctl_init
);
1481 * register_sysctl_table - register a sysctl hierarchy
1482 * @table: the top-level table structure
1484 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1485 * array. An entry with a ctl_name of 0 terminates the table.
1487 * The members of the &ctl_table structure are used as follows:
1489 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1490 * must be unique within that level of sysctl
1492 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1493 * enter a sysctl file
1495 * data - a pointer to data for use by proc_handler
1497 * maxlen - the maximum size in bytes of the data
1499 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1501 * child - a pointer to the child sysctl table if this entry is a directory, or
1504 * proc_handler - the text handler routine (described below)
1506 * strategy - the strategy routine (described below)
1508 * de - for internal use by the sysctl routines
1510 * extra1, extra2 - extra pointers usable by the proc handler routines
1512 * Leaf nodes in the sysctl tree will be represented by a single file
1513 * under /proc; non-leaf nodes will be represented by directories.
1515 * sysctl(2) can automatically manage read and write requests through
1516 * the sysctl table. The data and maxlen fields of the ctl_table
1517 * struct enable minimal validation of the values being written to be
1518 * performed, and the mode field allows minimal authentication.
1520 * More sophisticated management can be enabled by the provision of a
1521 * strategy routine with the table entry. This will be called before
1522 * any automatic read or write of the data is performed.
1524 * The strategy routine may return
1526 * < 0 - Error occurred (error is passed to user process)
1528 * 0 - OK - proceed with automatic read or write.
1530 * > 0 - OK - read or write has been done by the strategy routine, so
1531 * return immediately.
1533 * There must be a proc_handler routine for any terminal nodes
1534 * mirrored under /proc/sys (non-terminals are handled by a built-in
1535 * directory handler). Several default handlers are available to
1536 * cover common cases -
1538 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1539 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1540 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1542 * It is the handler's job to read the input buffer from user memory
1543 * and process it. The handler should return 0 on success.
1545 * This routine returns %NULL on a failure to register, and a pointer
1546 * to the table header on success.
1548 struct ctl_table_header
*register_sysctl_table(ctl_table
* table
)
1550 struct ctl_table_header
*tmp
;
1551 tmp
= kmalloc(sizeof(struct ctl_table_header
), GFP_KERNEL
);
1554 tmp
->ctl_table
= table
;
1555 INIT_LIST_HEAD(&tmp
->ctl_entry
);
1557 tmp
->unregistering
= NULL
;
1558 sysctl_set_parent(NULL
, table
);
1559 spin_lock(&sysctl_lock
);
1560 list_add_tail(&tmp
->ctl_entry
, &root_table_header
.ctl_entry
);
1561 spin_unlock(&sysctl_lock
);
1566 * unregister_sysctl_table - unregister a sysctl table hierarchy
1567 * @header: the header returned from register_sysctl_table
1569 * Unregisters the sysctl table and all children. proc entries may not
1570 * actually be removed until they are no longer used by anyone.
1572 void unregister_sysctl_table(struct ctl_table_header
* header
)
1575 spin_lock(&sysctl_lock
);
1576 start_unregistering(header
);
1577 spin_unlock(&sysctl_lock
);
1581 #else /* !CONFIG_SYSCTL */
1582 struct ctl_table_header
*register_sysctl_table(ctl_table
* table
)
1587 void unregister_sysctl_table(struct ctl_table_header
* table
)
1591 #endif /* CONFIG_SYSCTL */
1597 #ifdef CONFIG_PROC_SYSCTL
1599 static int _proc_do_string(void* data
, int maxlen
, int write
,
1600 struct file
*filp
, void __user
*buffer
,
1601 size_t *lenp
, loff_t
*ppos
)
1607 if (!data
|| !maxlen
|| !*lenp
) {
1615 while (len
< *lenp
) {
1616 if (get_user(c
, p
++))
1618 if (c
== 0 || c
== '\n')
1624 if(copy_from_user(data
, buffer
, len
))
1626 ((char *) data
)[len
] = 0;
1644 if(copy_to_user(buffer
, data
, len
))
1647 if(put_user('\n', ((char __user
*) buffer
) + len
))
1658 * proc_dostring - read a string sysctl
1659 * @table: the sysctl table
1660 * @write: %TRUE if this is a write to the sysctl file
1661 * @filp: the file structure
1662 * @buffer: the user buffer
1663 * @lenp: the size of the user buffer
1664 * @ppos: file position
1666 * Reads/writes a string from/to the user buffer. If the kernel
1667 * buffer provided is not large enough to hold the string, the
1668 * string is truncated. The copied string is %NULL-terminated.
1669 * If the string is being read by the user process, it is copied
1670 * and a newline '\n' is added. It is truncated if the buffer is
1673 * Returns 0 on success.
1675 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
1676 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1678 return _proc_do_string(table
->data
, table
->maxlen
, write
, filp
,
1679 buffer
, lenp
, ppos
);
1683 static int do_proc_dointvec_conv(int *negp
, unsigned long *lvalp
,
1685 int write
, void *data
)
1688 *valp
= *negp
? -*lvalp
: *lvalp
;
1693 *lvalp
= (unsigned long)-val
;
1696 *lvalp
= (unsigned long)val
;
1702 static int __do_proc_dointvec(void *tbl_data
, ctl_table
*table
,
1703 int write
, struct file
*filp
, void __user
*buffer
,
1704 size_t *lenp
, loff_t
*ppos
,
1705 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1706 int write
, void *data
),
1709 #define TMPBUFLEN 21
1710 int *i
, vleft
, first
=1, neg
, val
;
1714 char buf
[TMPBUFLEN
], *p
;
1715 char __user
*s
= buffer
;
1717 if (!tbl_data
|| !table
->maxlen
|| !*lenp
||
1718 (*ppos
&& !write
)) {
1723 i
= (int *) tbl_data
;
1724 vleft
= table
->maxlen
/ sizeof(*i
);
1728 conv
= do_proc_dointvec_conv
;
1730 for (; left
&& vleft
--; i
++, first
=0) {
1745 if (len
> sizeof(buf
) - 1)
1746 len
= sizeof(buf
) - 1;
1747 if (copy_from_user(buf
, s
, len
))
1751 if (*p
== '-' && left
> 1) {
1755 if (*p
< '0' || *p
> '9')
1758 lval
= simple_strtoul(p
, &p
, 0);
1761 if ((len
< left
) && *p
&& !isspace(*p
))
1768 if (conv(&neg
, &lval
, i
, 1, data
))
1775 if (conv(&neg
, &lval
, i
, 0, data
))
1778 sprintf(p
, "%s%lu", neg
? "-" : "", lval
);
1782 if(copy_to_user(s
, buf
, len
))
1789 if (!write
&& !first
&& left
) {
1790 if(put_user('\n', s
))
1797 if (get_user(c
, s
++))
1812 static int do_proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1813 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
1814 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1815 int write
, void *data
),
1818 return __do_proc_dointvec(table
->data
, table
, write
, filp
,
1819 buffer
, lenp
, ppos
, conv
, data
);
1823 * proc_dointvec - read a vector of integers
1824 * @table: the sysctl table
1825 * @write: %TRUE if this is a write to the sysctl file
1826 * @filp: the file structure
1827 * @buffer: the user buffer
1828 * @lenp: the size of the user buffer
1829 * @ppos: file position
1831 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1832 * values from/to the user buffer, treated as an ASCII string.
1834 * Returns 0 on success.
1836 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1837 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1839 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1847 static int do_proc_dointvec_bset_conv(int *negp
, unsigned long *lvalp
,
1849 int write
, void *data
)
1851 int op
= *(int *)data
;
1853 int val
= *negp
? -*lvalp
: *lvalp
;
1855 case OP_SET
: *valp
= val
; break;
1856 case OP_AND
: *valp
&= val
; break;
1857 case OP_OR
: *valp
|= val
; break;
1863 *lvalp
= (unsigned long)-val
;
1866 *lvalp
= (unsigned long)val
;
1873 * init may raise the set.
1876 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
1877 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1881 if (write
&& !capable(CAP_SYS_MODULE
)) {
1885 op
= is_init(current
) ? OP_SET
: OP_AND
;
1886 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1887 do_proc_dointvec_bset_conv
,&op
);
1891 * Taint values can only be increased
1893 static int proc_dointvec_taint(ctl_table
*table
, int write
, struct file
*filp
,
1894 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1898 if (write
&& !capable(CAP_SYS_ADMIN
))
1902 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1903 do_proc_dointvec_bset_conv
,&op
);
1906 struct do_proc_dointvec_minmax_conv_param
{
1911 static int do_proc_dointvec_minmax_conv(int *negp
, unsigned long *lvalp
,
1913 int write
, void *data
)
1915 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
1917 int val
= *negp
? -*lvalp
: *lvalp
;
1918 if ((param
->min
&& *param
->min
> val
) ||
1919 (param
->max
&& *param
->max
< val
))
1926 *lvalp
= (unsigned long)-val
;
1929 *lvalp
= (unsigned long)val
;
1936 * proc_dointvec_minmax - read a vector of integers with min/max values
1937 * @table: the sysctl table
1938 * @write: %TRUE if this is a write to the sysctl file
1939 * @filp: the file structure
1940 * @buffer: the user buffer
1941 * @lenp: the size of the user buffer
1942 * @ppos: file position
1944 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1945 * values from/to the user buffer, treated as an ASCII string.
1947 * This routine will ensure the values are within the range specified by
1948 * table->extra1 (min) and table->extra2 (max).
1950 * Returns 0 on success.
1952 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
1953 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1955 struct do_proc_dointvec_minmax_conv_param param
= {
1956 .min
= (int *) table
->extra1
,
1957 .max
= (int *) table
->extra2
,
1959 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
1960 do_proc_dointvec_minmax_conv
, ¶m
);
1963 static int __do_proc_doulongvec_minmax(void *data
, ctl_table
*table
, int write
,
1965 void __user
*buffer
,
1966 size_t *lenp
, loff_t
*ppos
,
1967 unsigned long convmul
,
1968 unsigned long convdiv
)
1970 #define TMPBUFLEN 21
1971 unsigned long *i
, *min
, *max
, val
;
1972 int vleft
, first
=1, neg
;
1974 char buf
[TMPBUFLEN
], *p
;
1975 char __user
*s
= buffer
;
1977 if (!data
|| !table
->maxlen
|| !*lenp
||
1978 (*ppos
&& !write
)) {
1983 i
= (unsigned long *) data
;
1984 min
= (unsigned long *) table
->extra1
;
1985 max
= (unsigned long *) table
->extra2
;
1986 vleft
= table
->maxlen
/ sizeof(unsigned long);
1989 for (; left
&& vleft
--; i
++, min
++, max
++, first
=0) {
2004 if (len
> TMPBUFLEN
-1)
2006 if (copy_from_user(buf
, s
, len
))
2010 if (*p
== '-' && left
> 1) {
2014 if (*p
< '0' || *p
> '9')
2016 val
= simple_strtoul(p
, &p
, 0) * convmul
/ convdiv
;
2018 if ((len
< left
) && *p
&& !isspace(*p
))
2027 if ((min
&& val
< *min
) || (max
&& val
> *max
))
2034 sprintf(p
, "%lu", convdiv
* (*i
) / convmul
);
2038 if(copy_to_user(s
, buf
, len
))
2045 if (!write
&& !first
&& left
) {
2046 if(put_user('\n', s
))
2053 if (get_user(c
, s
++))
2068 static int do_proc_doulongvec_minmax(ctl_table
*table
, int write
,
2070 void __user
*buffer
,
2071 size_t *lenp
, loff_t
*ppos
,
2072 unsigned long convmul
,
2073 unsigned long convdiv
)
2075 return __do_proc_doulongvec_minmax(table
->data
, table
, write
,
2076 filp
, buffer
, lenp
, ppos
, convmul
, convdiv
);
2080 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2081 * @table: the sysctl table
2082 * @write: %TRUE if this is a write to the sysctl file
2083 * @filp: the file structure
2084 * @buffer: the user buffer
2085 * @lenp: the size of the user buffer
2086 * @ppos: file position
2088 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2089 * values from/to the user buffer, treated as an ASCII string.
2091 * This routine will ensure the values are within the range specified by
2092 * table->extra1 (min) and table->extra2 (max).
2094 * Returns 0 on success.
2096 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2097 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2099 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
, lenp
, ppos
, 1l, 1l);
2103 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2104 * @table: the sysctl table
2105 * @write: %TRUE if this is a write to the sysctl file
2106 * @filp: the file structure
2107 * @buffer: the user buffer
2108 * @lenp: the size of the user buffer
2109 * @ppos: file position
2111 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2112 * values from/to the user buffer, treated as an ASCII string. The values
2113 * are treated as milliseconds, and converted to jiffies when they are stored.
2115 * This routine will ensure the values are within the range specified by
2116 * table->extra1 (min) and table->extra2 (max).
2118 * Returns 0 on success.
2120 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2122 void __user
*buffer
,
2123 size_t *lenp
, loff_t
*ppos
)
2125 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
,
2126 lenp
, ppos
, HZ
, 1000l);
2130 static int do_proc_dointvec_jiffies_conv(int *negp
, unsigned long *lvalp
,
2132 int write
, void *data
)
2135 if (*lvalp
> LONG_MAX
/ HZ
)
2137 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2143 lval
= (unsigned long)-val
;
2146 lval
= (unsigned long)val
;
2153 static int do_proc_dointvec_userhz_jiffies_conv(int *negp
, unsigned long *lvalp
,
2155 int write
, void *data
)
2158 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2160 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2166 lval
= (unsigned long)-val
;
2169 lval
= (unsigned long)val
;
2171 *lvalp
= jiffies_to_clock_t(lval
);
2176 static int do_proc_dointvec_ms_jiffies_conv(int *negp
, unsigned long *lvalp
,
2178 int write
, void *data
)
2181 *valp
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2187 lval
= (unsigned long)-val
;
2190 lval
= (unsigned long)val
;
2192 *lvalp
= jiffies_to_msecs(lval
);
2198 * proc_dointvec_jiffies - read a vector of integers as seconds
2199 * @table: the sysctl table
2200 * @write: %TRUE if this is a write to the sysctl file
2201 * @filp: the file structure
2202 * @buffer: the user buffer
2203 * @lenp: the size of the user buffer
2204 * @ppos: file position
2206 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2207 * values from/to the user buffer, treated as an ASCII string.
2208 * The values read are assumed to be in seconds, and are converted into
2211 * Returns 0 on success.
2213 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2214 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2216 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2217 do_proc_dointvec_jiffies_conv
,NULL
);
2221 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2222 * @table: the sysctl table
2223 * @write: %TRUE if this is a write to the sysctl file
2224 * @filp: the file structure
2225 * @buffer: the user buffer
2226 * @lenp: the size of the user buffer
2227 * @ppos: pointer to the file position
2229 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2230 * values from/to the user buffer, treated as an ASCII string.
2231 * The values read are assumed to be in 1/USER_HZ seconds, and
2232 * are converted into jiffies.
2234 * Returns 0 on success.
2236 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2237 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2239 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2240 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2244 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2245 * @table: the sysctl table
2246 * @write: %TRUE if this is a write to the sysctl file
2247 * @filp: the file structure
2248 * @buffer: the user buffer
2249 * @lenp: the size of the user buffer
2250 * @ppos: file position
2251 * @ppos: the current position in the file
2253 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2254 * values from/to the user buffer, treated as an ASCII string.
2255 * The values read are assumed to be in 1/1000 seconds, and
2256 * are converted into jiffies.
2258 * Returns 0 on success.
2260 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2261 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2263 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2264 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2267 static int proc_do_cad_pid(ctl_table
*table
, int write
, struct file
*filp
,
2268 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2270 struct pid
*new_pid
;
2274 tmp
= pid_nr(cad_pid
);
2276 r
= __do_proc_dointvec(&tmp
, table
, write
, filp
, buffer
,
2277 lenp
, ppos
, NULL
, NULL
);
2281 new_pid
= find_get_pid(tmp
);
2285 put_pid(xchg(&cad_pid
, new_pid
));
2289 #else /* CONFIG_PROC_FS */
2291 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
2292 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2297 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
2298 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2303 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
2304 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2309 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2310 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2315 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2316 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2321 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2322 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2327 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2328 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2333 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2334 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2339 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2341 void __user
*buffer
,
2342 size_t *lenp
, loff_t
*ppos
)
2348 #endif /* CONFIG_PROC_FS */
2351 #ifdef CONFIG_SYSCTL_SYSCALL
2353 * General sysctl support routines
2356 /* The generic string strategy routine: */
2357 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2358 void __user
*oldval
, size_t __user
*oldlenp
,
2359 void __user
*newval
, size_t newlen
)
2361 if (!table
->data
|| !table
->maxlen
)
2364 if (oldval
&& oldlenp
) {
2366 if (get_user(bufsize
, oldlenp
))
2369 size_t len
= strlen(table
->data
), copied
;
2371 /* This shouldn't trigger for a well-formed sysctl */
2372 if (len
> table
->maxlen
)
2373 len
= table
->maxlen
;
2375 /* Copy up to a max of bufsize-1 bytes of the string */
2376 copied
= (len
>= bufsize
) ? bufsize
- 1 : len
;
2378 if (copy_to_user(oldval
, table
->data
, copied
) ||
2379 put_user(0, (char __user
*)(oldval
+ copied
)))
2381 if (put_user(len
, oldlenp
))
2385 if (newval
&& newlen
) {
2386 size_t len
= newlen
;
2387 if (len
> table
->maxlen
)
2388 len
= table
->maxlen
;
2389 if(copy_from_user(table
->data
, newval
, len
))
2391 if (len
== table
->maxlen
)
2393 ((char *) table
->data
)[len
] = 0;
2399 * This function makes sure that all of the integers in the vector
2400 * are between the minimum and maximum values given in the arrays
2401 * table->extra1 and table->extra2, respectively.
2403 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2404 void __user
*oldval
, size_t __user
*oldlenp
,
2405 void __user
*newval
, size_t newlen
)
2408 if (newval
&& newlen
) {
2409 int __user
*vec
= (int __user
*) newval
;
2410 int *min
= (int *) table
->extra1
;
2411 int *max
= (int *) table
->extra2
;
2415 if (newlen
% sizeof(int) != 0)
2418 if (!table
->extra1
&& !table
->extra2
)
2421 if (newlen
> table
->maxlen
)
2422 newlen
= table
->maxlen
;
2423 length
= newlen
/ sizeof(int);
2425 for (i
= 0; i
< length
; i
++) {
2427 if (get_user(value
, vec
+ i
))
2429 if (min
&& value
< min
[i
])
2431 if (max
&& value
> max
[i
])
2438 /* Strategy function to convert jiffies to seconds */
2439 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2440 void __user
*oldval
, size_t __user
*oldlenp
,
2441 void __user
*newval
, size_t newlen
)
2443 if (oldval
&& oldlenp
) {
2446 if (get_user(olen
, oldlenp
))
2451 if (olen
< sizeof(int))
2454 val
= *(int *)(table
->data
) / HZ
;
2455 if (put_user(val
, (int __user
*)oldval
))
2457 if (put_user(sizeof(int), oldlenp
))
2461 if (newval
&& newlen
) {
2463 if (newlen
!= sizeof(int))
2465 if (get_user(new, (int __user
*)newval
))
2467 *(int *)(table
->data
) = new*HZ
;
2472 /* Strategy function to convert jiffies to seconds */
2473 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2474 void __user
*oldval
, size_t __user
*oldlenp
,
2475 void __user
*newval
, size_t newlen
)
2477 if (oldval
&& oldlenp
) {
2480 if (get_user(olen
, oldlenp
))
2485 if (olen
< sizeof(int))
2488 val
= jiffies_to_msecs(*(int *)(table
->data
));
2489 if (put_user(val
, (int __user
*)oldval
))
2491 if (put_user(sizeof(int), oldlenp
))
2495 if (newval
&& newlen
) {
2497 if (newlen
!= sizeof(int))
2499 if (get_user(new, (int __user
*)newval
))
2501 *(int *)(table
->data
) = msecs_to_jiffies(new);
2508 #else /* CONFIG_SYSCTL_SYSCALL */
2511 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
2513 static int msg_count
;
2514 struct __sysctl_args tmp
;
2515 int name
[CTL_MAXNAME
];
2518 /* Read in the sysctl name for better debug message logging */
2519 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
2521 if (tmp
.nlen
<= 0 || tmp
.nlen
>= CTL_MAXNAME
)
2523 for (i
= 0; i
< tmp
.nlen
; i
++)
2524 if (get_user(name
[i
], tmp
.name
+ i
))
2527 /* Ignore accesses to kernel.version */
2528 if ((tmp
.nlen
== 2) && (name
[0] == CTL_KERN
) && (name
[1] == KERN_VERSION
))
2531 if (msg_count
< 5) {
2534 "warning: process `%s' used the removed sysctl "
2535 "system call with ", current
->comm
);
2536 for (i
= 0; i
< tmp
.nlen
; i
++)
2537 printk("%d.", name
[i
]);
2544 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2545 void __user
*oldval
, size_t __user
*oldlenp
,
2546 void __user
*newval
, size_t newlen
)
2551 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2552 void __user
*oldval
, size_t __user
*oldlenp
,
2553 void __user
*newval
, size_t newlen
)
2558 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2559 void __user
*oldval
, size_t __user
*oldlenp
,
2560 void __user
*newval
, size_t newlen
)
2565 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2566 void __user
*oldval
, size_t __user
*oldlenp
,
2567 void __user
*newval
, size_t newlen
)
2572 #endif /* CONFIG_SYSCTL_SYSCALL */
2575 * No sense putting this after each symbol definition, twice,
2576 * exception granted :-)
2578 EXPORT_SYMBOL(proc_dointvec
);
2579 EXPORT_SYMBOL(proc_dointvec_jiffies
);
2580 EXPORT_SYMBOL(proc_dointvec_minmax
);
2581 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
2582 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
2583 EXPORT_SYMBOL(proc_dostring
);
2584 EXPORT_SYMBOL(proc_doulongvec_minmax
);
2585 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);
2586 EXPORT_SYMBOL(register_sysctl_table
);
2587 EXPORT_SYMBOL(sysctl_intvec
);
2588 EXPORT_SYMBOL(sysctl_jiffies
);
2589 EXPORT_SYMBOL(sysctl_ms_jiffies
);
2590 EXPORT_SYMBOL(sysctl_string
);
2591 EXPORT_SYMBOL(unregister_sysctl_table
);