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_granularity_ns",
226 .data
= &sysctl_sched_granularity
,
227 .maxlen
= sizeof(unsigned int),
229 .proc_handler
= &proc_dointvec_minmax
,
230 .strategy
= &sysctl_intvec
,
231 .extra1
= &min_sched_granularity_ns
,
232 .extra2
= &max_sched_granularity_ns
,
235 .ctl_name
= CTL_UNNUMBERED
,
236 .procname
= "sched_wakeup_granularity_ns",
237 .data
= &sysctl_sched_wakeup_granularity
,
238 .maxlen
= sizeof(unsigned int),
240 .proc_handler
= &proc_dointvec_minmax
,
241 .strategy
= &sysctl_intvec
,
242 .extra1
= &min_wakeup_granularity_ns
,
243 .extra2
= &max_wakeup_granularity_ns
,
246 .ctl_name
= CTL_UNNUMBERED
,
247 .procname
= "sched_batch_wakeup_granularity_ns",
248 .data
= &sysctl_sched_batch_wakeup_granularity
,
249 .maxlen
= sizeof(unsigned int),
251 .proc_handler
= &proc_dointvec_minmax
,
252 .strategy
= &sysctl_intvec
,
253 .extra1
= &min_wakeup_granularity_ns
,
254 .extra2
= &max_wakeup_granularity_ns
,
257 .ctl_name
= CTL_UNNUMBERED
,
258 .procname
= "sched_stat_granularity_ns",
259 .data
= &sysctl_sched_stat_granularity
,
260 .maxlen
= sizeof(unsigned int),
262 .proc_handler
= &proc_dointvec_minmax
,
263 .strategy
= &sysctl_intvec
,
264 .extra1
= &min_wakeup_granularity_ns
,
265 .extra2
= &max_wakeup_granularity_ns
,
268 .ctl_name
= CTL_UNNUMBERED
,
269 .procname
= "sched_runtime_limit_ns",
270 .data
= &sysctl_sched_runtime_limit
,
271 .maxlen
= sizeof(unsigned int),
273 .proc_handler
= &proc_dointvec_minmax
,
274 .strategy
= &sysctl_intvec
,
275 .extra1
= &min_sched_granularity_ns
,
276 .extra2
= &max_sched_granularity_ns
,
279 .ctl_name
= CTL_UNNUMBERED
,
280 .procname
= "sched_child_runs_first",
281 .data
= &sysctl_sched_child_runs_first
,
282 .maxlen
= sizeof(unsigned int),
284 .proc_handler
= &proc_dointvec
,
286 #ifdef CONFIG_PROVE_LOCKING
288 .ctl_name
= CTL_UNNUMBERED
,
289 .procname
= "prove_locking",
290 .data
= &prove_locking
,
291 .maxlen
= sizeof(int),
293 .proc_handler
= &proc_dointvec
,
296 #ifdef CONFIG_LOCK_STAT
298 .ctl_name
= CTL_UNNUMBERED
,
299 .procname
= "lock_stat",
301 .maxlen
= sizeof(int),
303 .proc_handler
= &proc_dointvec
,
307 .ctl_name
= CTL_UNNUMBERED
,
308 .procname
= "sched_features",
309 .data
= &sysctl_sched_features
,
310 .maxlen
= sizeof(unsigned int),
312 .proc_handler
= &proc_dointvec
,
316 .ctl_name
= KERN_PANIC
,
318 .data
= &panic_timeout
,
319 .maxlen
= sizeof(int),
321 .proc_handler
= &proc_dointvec
,
324 .ctl_name
= KERN_CORE_USES_PID
,
325 .procname
= "core_uses_pid",
326 .data
= &core_uses_pid
,
327 .maxlen
= sizeof(int),
329 .proc_handler
= &proc_dointvec
,
331 #ifdef CONFIG_AUDITSYSCALL
333 .ctl_name
= CTL_UNNUMBERED
,
334 .procname
= "audit_argv_kb",
335 .data
= &audit_argv_kb
,
336 .maxlen
= sizeof(int),
338 .proc_handler
= &proc_dointvec
,
342 .ctl_name
= KERN_CORE_PATTERN
,
343 .procname
= "core_pattern",
344 .data
= core_pattern
,
345 .maxlen
= CORENAME_MAX_SIZE
,
347 .proc_handler
= &proc_dostring
,
348 .strategy
= &sysctl_string
,
350 #ifdef CONFIG_PROC_SYSCTL
352 .ctl_name
= KERN_TAINTED
,
353 .procname
= "tainted",
355 .maxlen
= sizeof(int),
357 .proc_handler
= &proc_dointvec_taint
,
361 .ctl_name
= KERN_CAP_BSET
,
362 .procname
= "cap-bound",
364 .maxlen
= sizeof(kernel_cap_t
),
366 .proc_handler
= &proc_dointvec_bset
,
368 #ifdef CONFIG_BLK_DEV_INITRD
370 .ctl_name
= KERN_REALROOTDEV
,
371 .procname
= "real-root-dev",
372 .data
= &real_root_dev
,
373 .maxlen
= sizeof(int),
375 .proc_handler
= &proc_dointvec
,
379 .ctl_name
= CTL_UNNUMBERED
,
380 .procname
= "print-fatal-signals",
381 .data
= &print_fatal_signals
,
382 .maxlen
= sizeof(int),
384 .proc_handler
= &proc_dointvec
,
388 .ctl_name
= KERN_SPARC_REBOOT
,
389 .procname
= "reboot-cmd",
390 .data
= reboot_command
,
393 .proc_handler
= &proc_dostring
,
394 .strategy
= &sysctl_string
,
397 .ctl_name
= KERN_SPARC_STOP_A
,
398 .procname
= "stop-a",
399 .data
= &stop_a_enabled
,
400 .maxlen
= sizeof (int),
402 .proc_handler
= &proc_dointvec
,
405 .ctl_name
= KERN_SPARC_SCONS_PWROFF
,
406 .procname
= "scons-poweroff",
407 .data
= &scons_pwroff
,
408 .maxlen
= sizeof (int),
410 .proc_handler
= &proc_dointvec
,
415 .ctl_name
= KERN_HPPA_PWRSW
,
416 .procname
= "soft-power",
417 .data
= &pwrsw_enabled
,
418 .maxlen
= sizeof (int),
420 .proc_handler
= &proc_dointvec
,
423 .ctl_name
= KERN_HPPA_UNALIGNED
,
424 .procname
= "unaligned-trap",
425 .data
= &unaligned_enabled
,
426 .maxlen
= sizeof (int),
428 .proc_handler
= &proc_dointvec
,
432 .ctl_name
= KERN_CTLALTDEL
,
433 .procname
= "ctrl-alt-del",
435 .maxlen
= sizeof(int),
437 .proc_handler
= &proc_dointvec
,
440 .ctl_name
= KERN_PRINTK
,
441 .procname
= "printk",
442 .data
= &console_loglevel
,
443 .maxlen
= 4*sizeof(int),
445 .proc_handler
= &proc_dointvec
,
449 .ctl_name
= KERN_MODPROBE
,
450 .procname
= "modprobe",
451 .data
= &modprobe_path
,
452 .maxlen
= KMOD_PATH_LEN
,
454 .proc_handler
= &proc_dostring
,
455 .strategy
= &sysctl_string
,
458 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
460 .ctl_name
= KERN_HOTPLUG
,
461 .procname
= "hotplug",
462 .data
= &uevent_helper
,
463 .maxlen
= UEVENT_HELPER_PATH_LEN
,
465 .proc_handler
= &proc_dostring
,
466 .strategy
= &sysctl_string
,
469 #ifdef CONFIG_CHR_DEV_SG
471 .ctl_name
= KERN_SG_BIG_BUFF
,
472 .procname
= "sg-big-buff",
473 .data
= &sg_big_buff
,
474 .maxlen
= sizeof (int),
476 .proc_handler
= &proc_dointvec
,
479 #ifdef CONFIG_BSD_PROCESS_ACCT
481 .ctl_name
= KERN_ACCT
,
484 .maxlen
= 3*sizeof(int),
486 .proc_handler
= &proc_dointvec
,
489 #ifdef CONFIG_MAGIC_SYSRQ
491 .ctl_name
= KERN_SYSRQ
,
493 .data
= &__sysrq_enabled
,
494 .maxlen
= sizeof (int),
496 .proc_handler
= &proc_dointvec
,
499 #ifdef CONFIG_PROC_SYSCTL
501 .ctl_name
= KERN_CADPID
,
502 .procname
= "cad_pid",
504 .maxlen
= sizeof (int),
506 .proc_handler
= &proc_do_cad_pid
,
510 .ctl_name
= KERN_MAX_THREADS
,
511 .procname
= "threads-max",
512 .data
= &max_threads
,
513 .maxlen
= sizeof(int),
515 .proc_handler
= &proc_dointvec
,
518 .ctl_name
= KERN_RANDOM
,
519 .procname
= "random",
521 .child
= random_table
,
523 #ifdef CONFIG_UNIX98_PTYS
525 .ctl_name
= KERN_PTY
,
532 .ctl_name
= KERN_OVERFLOWUID
,
533 .procname
= "overflowuid",
534 .data
= &overflowuid
,
535 .maxlen
= sizeof(int),
537 .proc_handler
= &proc_dointvec_minmax
,
538 .strategy
= &sysctl_intvec
,
539 .extra1
= &minolduid
,
540 .extra2
= &maxolduid
,
543 .ctl_name
= KERN_OVERFLOWGID
,
544 .procname
= "overflowgid",
545 .data
= &overflowgid
,
546 .maxlen
= sizeof(int),
548 .proc_handler
= &proc_dointvec_minmax
,
549 .strategy
= &sysctl_intvec
,
550 .extra1
= &minolduid
,
551 .extra2
= &maxolduid
,
554 #ifdef CONFIG_MATHEMU
556 .ctl_name
= KERN_IEEE_EMULATION_WARNINGS
,
557 .procname
= "ieee_emulation_warnings",
558 .data
= &sysctl_ieee_emulation_warnings
,
559 .maxlen
= sizeof(int),
561 .proc_handler
= &proc_dointvec
,
564 #ifdef CONFIG_NO_IDLE_HZ
566 .ctl_name
= KERN_HZ_TIMER
,
567 .procname
= "hz_timer",
568 .data
= &sysctl_hz_timer
,
569 .maxlen
= sizeof(int),
571 .proc_handler
= &proc_dointvec
,
575 .ctl_name
= KERN_S390_USER_DEBUG_LOGGING
,
576 .procname
= "userprocess_debug",
577 .data
= &sysctl_userprocess_debug
,
578 .maxlen
= sizeof(int),
580 .proc_handler
= &proc_dointvec
,
584 .ctl_name
= KERN_PIDMAX
,
585 .procname
= "pid_max",
587 .maxlen
= sizeof (int),
589 .proc_handler
= &proc_dointvec_minmax
,
590 .strategy
= sysctl_intvec
,
591 .extra1
= &pid_max_min
,
592 .extra2
= &pid_max_max
,
595 .ctl_name
= KERN_PANIC_ON_OOPS
,
596 .procname
= "panic_on_oops",
597 .data
= &panic_on_oops
,
598 .maxlen
= sizeof(int),
600 .proc_handler
= &proc_dointvec
,
603 .ctl_name
= KERN_PRINTK_RATELIMIT
,
604 .procname
= "printk_ratelimit",
605 .data
= &printk_ratelimit_jiffies
,
606 .maxlen
= sizeof(int),
608 .proc_handler
= &proc_dointvec_jiffies
,
609 .strategy
= &sysctl_jiffies
,
612 .ctl_name
= KERN_PRINTK_RATELIMIT_BURST
,
613 .procname
= "printk_ratelimit_burst",
614 .data
= &printk_ratelimit_burst
,
615 .maxlen
= sizeof(int),
617 .proc_handler
= &proc_dointvec
,
620 .ctl_name
= KERN_NGROUPS_MAX
,
621 .procname
= "ngroups_max",
622 .data
= &ngroups_max
,
623 .maxlen
= sizeof (int),
625 .proc_handler
= &proc_dointvec
,
627 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
629 .ctl_name
= KERN_UNKNOWN_NMI_PANIC
,
630 .procname
= "unknown_nmi_panic",
631 .data
= &unknown_nmi_panic
,
632 .maxlen
= sizeof (int),
634 .proc_handler
= &proc_dointvec
,
637 .ctl_name
= KERN_NMI_WATCHDOG
,
638 .procname
= "nmi_watchdog",
639 .data
= &nmi_watchdog_enabled
,
640 .maxlen
= sizeof (int),
642 .proc_handler
= &proc_nmi_enabled
,
645 #if defined(CONFIG_X86)
647 .ctl_name
= KERN_PANIC_ON_NMI
,
648 .procname
= "panic_on_unrecovered_nmi",
649 .data
= &panic_on_unrecovered_nmi
,
650 .maxlen
= sizeof(int),
652 .proc_handler
= &proc_dointvec
,
655 .ctl_name
= KERN_BOOTLOADER_TYPE
,
656 .procname
= "bootloader_type",
657 .data
= &bootloader_type
,
658 .maxlen
= sizeof (int),
660 .proc_handler
= &proc_dointvec
,
663 .ctl_name
= CTL_UNNUMBERED
,
664 .procname
= "kstack_depth_to_print",
665 .data
= &kstack_depth_to_print
,
666 .maxlen
= sizeof(int),
668 .proc_handler
= &proc_dointvec
,
671 #if defined(CONFIG_MMU)
673 .ctl_name
= KERN_RANDOMIZE
,
674 .procname
= "randomize_va_space",
675 .data
= &randomize_va_space
,
676 .maxlen
= sizeof(int),
678 .proc_handler
= &proc_dointvec
,
681 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
683 .ctl_name
= KERN_SPIN_RETRY
,
684 .procname
= "spin_retry",
686 .maxlen
= sizeof (int),
688 .proc_handler
= &proc_dointvec
,
691 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
693 .ctl_name
= KERN_ACPI_VIDEO_FLAGS
,
694 .procname
= "acpi_video_flags",
695 .data
= &acpi_realmode_flags
,
696 .maxlen
= sizeof (unsigned long),
698 .proc_handler
= &proc_doulongvec_minmax
,
703 .ctl_name
= KERN_IA64_UNALIGNED
,
704 .procname
= "ignore-unaligned-usertrap",
705 .data
= &no_unaligned_warning
,
706 .maxlen
= sizeof (int),
708 .proc_handler
= &proc_dointvec
,
713 .ctl_name
= KERN_COMPAT_LOG
,
714 .procname
= "compat-log",
716 .maxlen
= sizeof (int),
718 .proc_handler
= &proc_dointvec
,
721 #ifdef CONFIG_RT_MUTEXES
723 .ctl_name
= KERN_MAX_LOCK_DEPTH
,
724 .procname
= "max_lock_depth",
725 .data
= &max_lock_depth
,
726 .maxlen
= sizeof(int),
728 .proc_handler
= &proc_dointvec
,
731 #ifdef CONFIG_PROC_FS
733 .ctl_name
= CTL_UNNUMBERED
,
734 .procname
= "maps_protect",
735 .data
= &maps_protect
,
736 .maxlen
= sizeof(int),
738 .proc_handler
= &proc_dointvec
,
742 .ctl_name
= CTL_UNNUMBERED
,
743 .procname
= "poweroff_cmd",
744 .data
= &poweroff_cmd
,
745 .maxlen
= POWEROFF_CMD_PATH_LEN
,
747 .proc_handler
= &proc_dostring
,
748 .strategy
= &sysctl_string
,
751 * NOTE: do not add new entries to this table unless you have read
752 * Documentation/sysctl/ctl_unnumbered.txt
757 /* Constants for minimum and maximum testing in vm_table.
758 We use these as one-element integer vectors. */
761 static int one_hundred
= 100;
764 static ctl_table vm_table
[] = {
766 .ctl_name
= VM_OVERCOMMIT_MEMORY
,
767 .procname
= "overcommit_memory",
768 .data
= &sysctl_overcommit_memory
,
769 .maxlen
= sizeof(sysctl_overcommit_memory
),
771 .proc_handler
= &proc_dointvec
,
774 .ctl_name
= VM_PANIC_ON_OOM
,
775 .procname
= "panic_on_oom",
776 .data
= &sysctl_panic_on_oom
,
777 .maxlen
= sizeof(sysctl_panic_on_oom
),
779 .proc_handler
= &proc_dointvec
,
782 .ctl_name
= VM_OVERCOMMIT_RATIO
,
783 .procname
= "overcommit_ratio",
784 .data
= &sysctl_overcommit_ratio
,
785 .maxlen
= sizeof(sysctl_overcommit_ratio
),
787 .proc_handler
= &proc_dointvec
,
790 .ctl_name
= VM_PAGE_CLUSTER
,
791 .procname
= "page-cluster",
792 .data
= &page_cluster
,
793 .maxlen
= sizeof(int),
795 .proc_handler
= &proc_dointvec
,
798 .ctl_name
= VM_DIRTY_BACKGROUND
,
799 .procname
= "dirty_background_ratio",
800 .data
= &dirty_background_ratio
,
801 .maxlen
= sizeof(dirty_background_ratio
),
803 .proc_handler
= &proc_dointvec_minmax
,
804 .strategy
= &sysctl_intvec
,
806 .extra2
= &one_hundred
,
809 .ctl_name
= VM_DIRTY_RATIO
,
810 .procname
= "dirty_ratio",
811 .data
= &vm_dirty_ratio
,
812 .maxlen
= sizeof(vm_dirty_ratio
),
814 .proc_handler
= &proc_dointvec_minmax
,
815 .strategy
= &sysctl_intvec
,
817 .extra2
= &one_hundred
,
820 .ctl_name
= VM_DIRTY_WB_CS
,
821 .procname
= "dirty_writeback_centisecs",
822 .data
= &dirty_writeback_interval
,
823 .maxlen
= sizeof(dirty_writeback_interval
),
825 .proc_handler
= &dirty_writeback_centisecs_handler
,
828 .ctl_name
= VM_DIRTY_EXPIRE_CS
,
829 .procname
= "dirty_expire_centisecs",
830 .data
= &dirty_expire_interval
,
831 .maxlen
= sizeof(dirty_expire_interval
),
833 .proc_handler
= &proc_dointvec_userhz_jiffies
,
836 .ctl_name
= VM_NR_PDFLUSH_THREADS
,
837 .procname
= "nr_pdflush_threads",
838 .data
= &nr_pdflush_threads
,
839 .maxlen
= sizeof nr_pdflush_threads
,
840 .mode
= 0444 /* read-only*/,
841 .proc_handler
= &proc_dointvec
,
844 .ctl_name
= VM_SWAPPINESS
,
845 .procname
= "swappiness",
846 .data
= &vm_swappiness
,
847 .maxlen
= sizeof(vm_swappiness
),
849 .proc_handler
= &proc_dointvec_minmax
,
850 .strategy
= &sysctl_intvec
,
852 .extra2
= &one_hundred
,
854 #ifdef CONFIG_HUGETLB_PAGE
856 .ctl_name
= VM_HUGETLB_PAGES
,
857 .procname
= "nr_hugepages",
858 .data
= &max_huge_pages
,
859 .maxlen
= sizeof(unsigned long),
861 .proc_handler
= &hugetlb_sysctl_handler
,
862 .extra1
= (void *)&hugetlb_zero
,
863 .extra2
= (void *)&hugetlb_infinity
,
866 .ctl_name
= VM_HUGETLB_GROUP
,
867 .procname
= "hugetlb_shm_group",
868 .data
= &sysctl_hugetlb_shm_group
,
869 .maxlen
= sizeof(gid_t
),
871 .proc_handler
= &proc_dointvec
,
874 .ctl_name
= CTL_UNNUMBERED
,
875 .procname
= "hugepages_treat_as_movable",
876 .data
= &hugepages_treat_as_movable
,
877 .maxlen
= sizeof(int),
879 .proc_handler
= &hugetlb_treat_movable_handler
,
883 .ctl_name
= VM_LOWMEM_RESERVE_RATIO
,
884 .procname
= "lowmem_reserve_ratio",
885 .data
= &sysctl_lowmem_reserve_ratio
,
886 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
888 .proc_handler
= &lowmem_reserve_ratio_sysctl_handler
,
889 .strategy
= &sysctl_intvec
,
892 .ctl_name
= VM_DROP_PAGECACHE
,
893 .procname
= "drop_caches",
894 .data
= &sysctl_drop_caches
,
895 .maxlen
= sizeof(int),
897 .proc_handler
= drop_caches_sysctl_handler
,
898 .strategy
= &sysctl_intvec
,
901 .ctl_name
= VM_MIN_FREE_KBYTES
,
902 .procname
= "min_free_kbytes",
903 .data
= &min_free_kbytes
,
904 .maxlen
= sizeof(min_free_kbytes
),
906 .proc_handler
= &min_free_kbytes_sysctl_handler
,
907 .strategy
= &sysctl_intvec
,
911 .ctl_name
= VM_PERCPU_PAGELIST_FRACTION
,
912 .procname
= "percpu_pagelist_fraction",
913 .data
= &percpu_pagelist_fraction
,
914 .maxlen
= sizeof(percpu_pagelist_fraction
),
916 .proc_handler
= &percpu_pagelist_fraction_sysctl_handler
,
917 .strategy
= &sysctl_intvec
,
918 .extra1
= &min_percpu_pagelist_fract
,
922 .ctl_name
= VM_MAX_MAP_COUNT
,
923 .procname
= "max_map_count",
924 .data
= &sysctl_max_map_count
,
925 .maxlen
= sizeof(sysctl_max_map_count
),
927 .proc_handler
= &proc_dointvec
931 .ctl_name
= VM_LAPTOP_MODE
,
932 .procname
= "laptop_mode",
933 .data
= &laptop_mode
,
934 .maxlen
= sizeof(laptop_mode
),
936 .proc_handler
= &proc_dointvec_jiffies
,
937 .strategy
= &sysctl_jiffies
,
940 .ctl_name
= VM_BLOCK_DUMP
,
941 .procname
= "block_dump",
943 .maxlen
= sizeof(block_dump
),
945 .proc_handler
= &proc_dointvec
,
946 .strategy
= &sysctl_intvec
,
950 .ctl_name
= VM_VFS_CACHE_PRESSURE
,
951 .procname
= "vfs_cache_pressure",
952 .data
= &sysctl_vfs_cache_pressure
,
953 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
955 .proc_handler
= &proc_dointvec
,
956 .strategy
= &sysctl_intvec
,
959 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
961 .ctl_name
= VM_LEGACY_VA_LAYOUT
,
962 .procname
= "legacy_va_layout",
963 .data
= &sysctl_legacy_va_layout
,
964 .maxlen
= sizeof(sysctl_legacy_va_layout
),
966 .proc_handler
= &proc_dointvec
,
967 .strategy
= &sysctl_intvec
,
973 .ctl_name
= VM_ZONE_RECLAIM_MODE
,
974 .procname
= "zone_reclaim_mode",
975 .data
= &zone_reclaim_mode
,
976 .maxlen
= sizeof(zone_reclaim_mode
),
978 .proc_handler
= &proc_dointvec
,
979 .strategy
= &sysctl_intvec
,
983 .ctl_name
= VM_MIN_UNMAPPED
,
984 .procname
= "min_unmapped_ratio",
985 .data
= &sysctl_min_unmapped_ratio
,
986 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
988 .proc_handler
= &sysctl_min_unmapped_ratio_sysctl_handler
,
989 .strategy
= &sysctl_intvec
,
991 .extra2
= &one_hundred
,
994 .ctl_name
= VM_MIN_SLAB
,
995 .procname
= "min_slab_ratio",
996 .data
= &sysctl_min_slab_ratio
,
997 .maxlen
= sizeof(sysctl_min_slab_ratio
),
999 .proc_handler
= &sysctl_min_slab_ratio_sysctl_handler
,
1000 .strategy
= &sysctl_intvec
,
1002 .extra2
= &one_hundred
,
1007 .ctl_name
= CTL_UNNUMBERED
,
1008 .procname
= "stat_interval",
1009 .data
= &sysctl_stat_interval
,
1010 .maxlen
= sizeof(sysctl_stat_interval
),
1012 .proc_handler
= &proc_dointvec_jiffies
,
1013 .strategy
= &sysctl_jiffies
,
1016 #ifdef CONFIG_SECURITY
1018 .ctl_name
= CTL_UNNUMBERED
,
1019 .procname
= "mmap_min_addr",
1020 .data
= &mmap_min_addr
,
1021 .maxlen
= sizeof(unsigned long),
1023 .proc_handler
= &proc_doulongvec_minmax
,
1028 .ctl_name
= CTL_UNNUMBERED
,
1029 .procname
= "numa_zonelist_order",
1030 .data
= &numa_zonelist_order
,
1031 .maxlen
= NUMA_ZONELIST_ORDER_LEN
,
1033 .proc_handler
= &numa_zonelist_order_handler
,
1034 .strategy
= &sysctl_string
,
1037 #if defined(CONFIG_X86_32) || \
1038 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1040 .ctl_name
= VM_VDSO_ENABLED
,
1041 .procname
= "vdso_enabled",
1042 .data
= &vdso_enabled
,
1043 .maxlen
= sizeof(vdso_enabled
),
1045 .proc_handler
= &proc_dointvec
,
1046 .strategy
= &sysctl_intvec
,
1051 * NOTE: do not add new entries to this table unless you have read
1052 * Documentation/sysctl/ctl_unnumbered.txt
1057 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1058 static ctl_table binfmt_misc_table
[] = {
1063 static ctl_table fs_table
[] = {
1065 .ctl_name
= FS_NRINODE
,
1066 .procname
= "inode-nr",
1067 .data
= &inodes_stat
,
1068 .maxlen
= 2*sizeof(int),
1070 .proc_handler
= &proc_dointvec
,
1073 .ctl_name
= FS_STATINODE
,
1074 .procname
= "inode-state",
1075 .data
= &inodes_stat
,
1076 .maxlen
= 7*sizeof(int),
1078 .proc_handler
= &proc_dointvec
,
1081 .ctl_name
= FS_NRFILE
,
1082 .procname
= "file-nr",
1083 .data
= &files_stat
,
1084 .maxlen
= 3*sizeof(int),
1086 .proc_handler
= &proc_nr_files
,
1089 .ctl_name
= FS_MAXFILE
,
1090 .procname
= "file-max",
1091 .data
= &files_stat
.max_files
,
1092 .maxlen
= sizeof(int),
1094 .proc_handler
= &proc_dointvec
,
1097 .ctl_name
= FS_DENTRY
,
1098 .procname
= "dentry-state",
1099 .data
= &dentry_stat
,
1100 .maxlen
= 6*sizeof(int),
1102 .proc_handler
= &proc_dointvec
,
1105 .ctl_name
= FS_OVERFLOWUID
,
1106 .procname
= "overflowuid",
1107 .data
= &fs_overflowuid
,
1108 .maxlen
= sizeof(int),
1110 .proc_handler
= &proc_dointvec_minmax
,
1111 .strategy
= &sysctl_intvec
,
1112 .extra1
= &minolduid
,
1113 .extra2
= &maxolduid
,
1116 .ctl_name
= FS_OVERFLOWGID
,
1117 .procname
= "overflowgid",
1118 .data
= &fs_overflowgid
,
1119 .maxlen
= sizeof(int),
1121 .proc_handler
= &proc_dointvec_minmax
,
1122 .strategy
= &sysctl_intvec
,
1123 .extra1
= &minolduid
,
1124 .extra2
= &maxolduid
,
1127 .ctl_name
= FS_LEASES
,
1128 .procname
= "leases-enable",
1129 .data
= &leases_enable
,
1130 .maxlen
= sizeof(int),
1132 .proc_handler
= &proc_dointvec
,
1134 #ifdef CONFIG_DNOTIFY
1136 .ctl_name
= FS_DIR_NOTIFY
,
1137 .procname
= "dir-notify-enable",
1138 .data
= &dir_notify_enable
,
1139 .maxlen
= sizeof(int),
1141 .proc_handler
= &proc_dointvec
,
1146 .ctl_name
= FS_LEASE_TIME
,
1147 .procname
= "lease-break-time",
1148 .data
= &lease_break_time
,
1149 .maxlen
= sizeof(int),
1151 .proc_handler
= &proc_dointvec_minmax
,
1152 .strategy
= &sysctl_intvec
,
1157 .ctl_name
= FS_AIO_NR
,
1158 .procname
= "aio-nr",
1160 .maxlen
= sizeof(aio_nr
),
1162 .proc_handler
= &proc_doulongvec_minmax
,
1165 .ctl_name
= FS_AIO_MAX_NR
,
1166 .procname
= "aio-max-nr",
1167 .data
= &aio_max_nr
,
1168 .maxlen
= sizeof(aio_max_nr
),
1170 .proc_handler
= &proc_doulongvec_minmax
,
1172 #ifdef CONFIG_INOTIFY_USER
1174 .ctl_name
= FS_INOTIFY
,
1175 .procname
= "inotify",
1177 .child
= inotify_table
,
1182 .ctl_name
= KERN_SETUID_DUMPABLE
,
1183 .procname
= "suid_dumpable",
1184 .data
= &suid_dumpable
,
1185 .maxlen
= sizeof(int),
1187 .proc_handler
= &proc_dointvec
,
1189 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1191 .ctl_name
= CTL_UNNUMBERED
,
1192 .procname
= "binfmt_misc",
1194 .child
= binfmt_misc_table
,
1198 * NOTE: do not add new entries to this table unless you have read
1199 * Documentation/sysctl/ctl_unnumbered.txt
1204 static ctl_table debug_table
[] = {
1207 .ctl_name
= CTL_UNNUMBERED
,
1208 .procname
= "exception-trace",
1209 .data
= &show_unhandled_signals
,
1210 .maxlen
= sizeof(int),
1212 .proc_handler
= proc_dointvec
1218 static ctl_table dev_table
[] = {
1222 static DEFINE_SPINLOCK(sysctl_lock
);
1224 /* called under sysctl_lock */
1225 static int use_table(struct ctl_table_header
*p
)
1227 if (unlikely(p
->unregistering
))
1233 /* called under sysctl_lock */
1234 static void unuse_table(struct ctl_table_header
*p
)
1237 if (unlikely(p
->unregistering
))
1238 complete(p
->unregistering
);
1241 /* called under sysctl_lock, will reacquire if has to wait */
1242 static void start_unregistering(struct ctl_table_header
*p
)
1245 * if p->used is 0, nobody will ever touch that entry again;
1246 * we'll eliminate all paths to it before dropping sysctl_lock
1248 if (unlikely(p
->used
)) {
1249 struct completion wait
;
1250 init_completion(&wait
);
1251 p
->unregistering
= &wait
;
1252 spin_unlock(&sysctl_lock
);
1253 wait_for_completion(&wait
);
1254 spin_lock(&sysctl_lock
);
1257 * do not remove from the list until nobody holds it; walking the
1258 * list in do_sysctl() relies on that.
1260 list_del_init(&p
->ctl_entry
);
1263 void sysctl_head_finish(struct ctl_table_header
*head
)
1267 spin_lock(&sysctl_lock
);
1269 spin_unlock(&sysctl_lock
);
1272 struct ctl_table_header
*sysctl_head_next(struct ctl_table_header
*prev
)
1274 struct ctl_table_header
*head
;
1275 struct list_head
*tmp
;
1276 spin_lock(&sysctl_lock
);
1278 tmp
= &prev
->ctl_entry
;
1282 tmp
= &root_table_header
.ctl_entry
;
1284 head
= list_entry(tmp
, struct ctl_table_header
, ctl_entry
);
1286 if (!use_table(head
))
1288 spin_unlock(&sysctl_lock
);
1292 if (tmp
== &root_table_header
.ctl_entry
)
1295 spin_unlock(&sysctl_lock
);
1299 #ifdef CONFIG_SYSCTL_SYSCALL
1300 int do_sysctl(int __user
*name
, int nlen
, void __user
*oldval
, size_t __user
*oldlenp
,
1301 void __user
*newval
, size_t newlen
)
1303 struct ctl_table_header
*head
;
1304 int error
= -ENOTDIR
;
1306 if (nlen
<= 0 || nlen
>= CTL_MAXNAME
)
1310 if (!oldlenp
|| get_user(old_len
, oldlenp
))
1314 for (head
= sysctl_head_next(NULL
); head
;
1315 head
= sysctl_head_next(head
)) {
1316 error
= parse_table(name
, nlen
, oldval
, oldlenp
,
1317 newval
, newlen
, head
->ctl_table
);
1318 if (error
!= -ENOTDIR
) {
1319 sysctl_head_finish(head
);
1326 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
1328 struct __sysctl_args tmp
;
1331 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
1335 error
= do_sysctl(tmp
.name
, tmp
.nlen
, tmp
.oldval
, tmp
.oldlenp
,
1336 tmp
.newval
, tmp
.newlen
);
1340 #endif /* CONFIG_SYSCTL_SYSCALL */
1343 * sysctl_perm does NOT grant the superuser all rights automatically, because
1344 * some sysctl variables are readonly even to root.
1347 static int test_perm(int mode
, int op
)
1351 else if (in_egroup_p(0))
1353 if ((mode
& op
& 0007) == op
)
1358 int sysctl_perm(ctl_table
*table
, int op
)
1361 error
= security_sysctl(table
, op
);
1364 return test_perm(table
->mode
, op
);
1367 #ifdef CONFIG_SYSCTL_SYSCALL
1368 static int parse_table(int __user
*name
, int nlen
,
1369 void __user
*oldval
, size_t __user
*oldlenp
,
1370 void __user
*newval
, size_t newlen
,
1377 if (get_user(n
, name
))
1379 for ( ; table
->ctl_name
|| table
->procname
; table
++) {
1380 if (!table
->ctl_name
)
1382 if (n
== table
->ctl_name
) {
1385 if (sysctl_perm(table
, 001))
1389 table
= table
->child
;
1392 error
= do_sysctl_strategy(table
, name
, nlen
,
1401 /* Perform the actual read/write of a sysctl table entry. */
1402 int do_sysctl_strategy (ctl_table
*table
,
1403 int __user
*name
, int nlen
,
1404 void __user
*oldval
, size_t __user
*oldlenp
,
1405 void __user
*newval
, size_t newlen
)
1414 if (sysctl_perm(table
, op
))
1417 if (table
->strategy
) {
1418 rc
= table
->strategy(table
, name
, nlen
, oldval
, oldlenp
,
1426 /* If there is no strategy routine, or if the strategy returns
1427 * zero, proceed with automatic r/w */
1428 if (table
->data
&& table
->maxlen
) {
1429 if (oldval
&& oldlenp
) {
1430 if (get_user(len
, oldlenp
))
1433 if (len
> table
->maxlen
)
1434 len
= table
->maxlen
;
1435 if(copy_to_user(oldval
, table
->data
, len
))
1437 if(put_user(len
, oldlenp
))
1441 if (newval
&& newlen
) {
1443 if (len
> table
->maxlen
)
1444 len
= table
->maxlen
;
1445 if(copy_from_user(table
->data
, newval
, len
))
1451 #endif /* CONFIG_SYSCTL_SYSCALL */
1453 static void sysctl_set_parent(struct ctl_table
*parent
, struct ctl_table
*table
)
1455 for (; table
->ctl_name
|| table
->procname
; table
++) {
1456 table
->parent
= parent
;
1458 sysctl_set_parent(table
, table
->child
);
1462 static __init
int sysctl_init(void)
1464 sysctl_set_parent(NULL
, root_table
);
1468 core_initcall(sysctl_init
);
1471 * register_sysctl_table - register a sysctl hierarchy
1472 * @table: the top-level table structure
1474 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1475 * array. An entry with a ctl_name of 0 terminates the table.
1477 * The members of the &ctl_table structure are used as follows:
1479 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1480 * must be unique within that level of sysctl
1482 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1483 * enter a sysctl file
1485 * data - a pointer to data for use by proc_handler
1487 * maxlen - the maximum size in bytes of the data
1489 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1491 * child - a pointer to the child sysctl table if this entry is a directory, or
1494 * proc_handler - the text handler routine (described below)
1496 * strategy - the strategy routine (described below)
1498 * de - for internal use by the sysctl routines
1500 * extra1, extra2 - extra pointers usable by the proc handler routines
1502 * Leaf nodes in the sysctl tree will be represented by a single file
1503 * under /proc; non-leaf nodes will be represented by directories.
1505 * sysctl(2) can automatically manage read and write requests through
1506 * the sysctl table. The data and maxlen fields of the ctl_table
1507 * struct enable minimal validation of the values being written to be
1508 * performed, and the mode field allows minimal authentication.
1510 * More sophisticated management can be enabled by the provision of a
1511 * strategy routine with the table entry. This will be called before
1512 * any automatic read or write of the data is performed.
1514 * The strategy routine may return
1516 * < 0 - Error occurred (error is passed to user process)
1518 * 0 - OK - proceed with automatic read or write.
1520 * > 0 - OK - read or write has been done by the strategy routine, so
1521 * return immediately.
1523 * There must be a proc_handler routine for any terminal nodes
1524 * mirrored under /proc/sys (non-terminals are handled by a built-in
1525 * directory handler). Several default handlers are available to
1526 * cover common cases -
1528 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1529 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1530 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1532 * It is the handler's job to read the input buffer from user memory
1533 * and process it. The handler should return 0 on success.
1535 * This routine returns %NULL on a failure to register, and a pointer
1536 * to the table header on success.
1538 struct ctl_table_header
*register_sysctl_table(ctl_table
* table
)
1540 struct ctl_table_header
*tmp
;
1541 tmp
= kmalloc(sizeof(struct ctl_table_header
), GFP_KERNEL
);
1544 tmp
->ctl_table
= table
;
1545 INIT_LIST_HEAD(&tmp
->ctl_entry
);
1547 tmp
->unregistering
= NULL
;
1548 sysctl_set_parent(NULL
, table
);
1549 spin_lock(&sysctl_lock
);
1550 list_add_tail(&tmp
->ctl_entry
, &root_table_header
.ctl_entry
);
1551 spin_unlock(&sysctl_lock
);
1556 * unregister_sysctl_table - unregister a sysctl table hierarchy
1557 * @header: the header returned from register_sysctl_table
1559 * Unregisters the sysctl table and all children. proc entries may not
1560 * actually be removed until they are no longer used by anyone.
1562 void unregister_sysctl_table(struct ctl_table_header
* header
)
1565 spin_lock(&sysctl_lock
);
1566 start_unregistering(header
);
1567 spin_unlock(&sysctl_lock
);
1571 #else /* !CONFIG_SYSCTL */
1572 struct ctl_table_header
*register_sysctl_table(ctl_table
* table
)
1577 void unregister_sysctl_table(struct ctl_table_header
* table
)
1581 #endif /* CONFIG_SYSCTL */
1587 #ifdef CONFIG_PROC_SYSCTL
1589 static int _proc_do_string(void* data
, int maxlen
, int write
,
1590 struct file
*filp
, void __user
*buffer
,
1591 size_t *lenp
, loff_t
*ppos
)
1597 if (!data
|| !maxlen
|| !*lenp
) {
1605 while (len
< *lenp
) {
1606 if (get_user(c
, p
++))
1608 if (c
== 0 || c
== '\n')
1614 if(copy_from_user(data
, buffer
, len
))
1616 ((char *) data
)[len
] = 0;
1634 if(copy_to_user(buffer
, data
, len
))
1637 if(put_user('\n', ((char __user
*) buffer
) + len
))
1648 * proc_dostring - read a string sysctl
1649 * @table: the sysctl table
1650 * @write: %TRUE if this is a write to the sysctl file
1651 * @filp: the file structure
1652 * @buffer: the user buffer
1653 * @lenp: the size of the user buffer
1654 * @ppos: file position
1656 * Reads/writes a string from/to the user buffer. If the kernel
1657 * buffer provided is not large enough to hold the string, the
1658 * string is truncated. The copied string is %NULL-terminated.
1659 * If the string is being read by the user process, it is copied
1660 * and a newline '\n' is added. It is truncated if the buffer is
1663 * Returns 0 on success.
1665 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
1666 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1668 return _proc_do_string(table
->data
, table
->maxlen
, write
, filp
,
1669 buffer
, lenp
, ppos
);
1673 static int do_proc_dointvec_conv(int *negp
, unsigned long *lvalp
,
1675 int write
, void *data
)
1678 *valp
= *negp
? -*lvalp
: *lvalp
;
1683 *lvalp
= (unsigned long)-val
;
1686 *lvalp
= (unsigned long)val
;
1692 static int __do_proc_dointvec(void *tbl_data
, ctl_table
*table
,
1693 int write
, struct file
*filp
, void __user
*buffer
,
1694 size_t *lenp
, loff_t
*ppos
,
1695 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1696 int write
, void *data
),
1699 #define TMPBUFLEN 21
1700 int *i
, vleft
, first
=1, neg
, val
;
1704 char buf
[TMPBUFLEN
], *p
;
1705 char __user
*s
= buffer
;
1707 if (!tbl_data
|| !table
->maxlen
|| !*lenp
||
1708 (*ppos
&& !write
)) {
1713 i
= (int *) tbl_data
;
1714 vleft
= table
->maxlen
/ sizeof(*i
);
1718 conv
= do_proc_dointvec_conv
;
1720 for (; left
&& vleft
--; i
++, first
=0) {
1735 if (len
> sizeof(buf
) - 1)
1736 len
= sizeof(buf
) - 1;
1737 if (copy_from_user(buf
, s
, len
))
1741 if (*p
== '-' && left
> 1) {
1745 if (*p
< '0' || *p
> '9')
1748 lval
= simple_strtoul(p
, &p
, 0);
1751 if ((len
< left
) && *p
&& !isspace(*p
))
1758 if (conv(&neg
, &lval
, i
, 1, data
))
1765 if (conv(&neg
, &lval
, i
, 0, data
))
1768 sprintf(p
, "%s%lu", neg
? "-" : "", lval
);
1772 if(copy_to_user(s
, buf
, len
))
1779 if (!write
&& !first
&& left
) {
1780 if(put_user('\n', s
))
1787 if (get_user(c
, s
++))
1802 static int do_proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1803 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
1804 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1805 int write
, void *data
),
1808 return __do_proc_dointvec(table
->data
, table
, write
, filp
,
1809 buffer
, lenp
, ppos
, conv
, data
);
1813 * proc_dointvec - read a vector of integers
1814 * @table: the sysctl table
1815 * @write: %TRUE if this is a write to the sysctl file
1816 * @filp: the file structure
1817 * @buffer: the user buffer
1818 * @lenp: the size of the user buffer
1819 * @ppos: file position
1821 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1822 * values from/to the user buffer, treated as an ASCII string.
1824 * Returns 0 on success.
1826 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1827 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1829 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1837 static int do_proc_dointvec_bset_conv(int *negp
, unsigned long *lvalp
,
1839 int write
, void *data
)
1841 int op
= *(int *)data
;
1843 int val
= *negp
? -*lvalp
: *lvalp
;
1845 case OP_SET
: *valp
= val
; break;
1846 case OP_AND
: *valp
&= val
; break;
1847 case OP_OR
: *valp
|= val
; break;
1853 *lvalp
= (unsigned long)-val
;
1856 *lvalp
= (unsigned long)val
;
1863 * init may raise the set.
1866 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
1867 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1871 if (write
&& !capable(CAP_SYS_MODULE
)) {
1875 op
= is_init(current
) ? OP_SET
: OP_AND
;
1876 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1877 do_proc_dointvec_bset_conv
,&op
);
1881 * Taint values can only be increased
1883 static int proc_dointvec_taint(ctl_table
*table
, int write
, struct file
*filp
,
1884 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1888 if (write
&& !capable(CAP_SYS_ADMIN
))
1892 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1893 do_proc_dointvec_bset_conv
,&op
);
1896 struct do_proc_dointvec_minmax_conv_param
{
1901 static int do_proc_dointvec_minmax_conv(int *negp
, unsigned long *lvalp
,
1903 int write
, void *data
)
1905 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
1907 int val
= *negp
? -*lvalp
: *lvalp
;
1908 if ((param
->min
&& *param
->min
> val
) ||
1909 (param
->max
&& *param
->max
< val
))
1916 *lvalp
= (unsigned long)-val
;
1919 *lvalp
= (unsigned long)val
;
1926 * proc_dointvec_minmax - read a vector of integers with min/max values
1927 * @table: the sysctl table
1928 * @write: %TRUE if this is a write to the sysctl file
1929 * @filp: the file structure
1930 * @buffer: the user buffer
1931 * @lenp: the size of the user buffer
1932 * @ppos: file position
1934 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1935 * values from/to the user buffer, treated as an ASCII string.
1937 * This routine will ensure the values are within the range specified by
1938 * table->extra1 (min) and table->extra2 (max).
1940 * Returns 0 on success.
1942 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
1943 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1945 struct do_proc_dointvec_minmax_conv_param param
= {
1946 .min
= (int *) table
->extra1
,
1947 .max
= (int *) table
->extra2
,
1949 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
1950 do_proc_dointvec_minmax_conv
, ¶m
);
1953 static int __do_proc_doulongvec_minmax(void *data
, ctl_table
*table
, int write
,
1955 void __user
*buffer
,
1956 size_t *lenp
, loff_t
*ppos
,
1957 unsigned long convmul
,
1958 unsigned long convdiv
)
1960 #define TMPBUFLEN 21
1961 unsigned long *i
, *min
, *max
, val
;
1962 int vleft
, first
=1, neg
;
1964 char buf
[TMPBUFLEN
], *p
;
1965 char __user
*s
= buffer
;
1967 if (!data
|| !table
->maxlen
|| !*lenp
||
1968 (*ppos
&& !write
)) {
1973 i
= (unsigned long *) data
;
1974 min
= (unsigned long *) table
->extra1
;
1975 max
= (unsigned long *) table
->extra2
;
1976 vleft
= table
->maxlen
/ sizeof(unsigned long);
1979 for (; left
&& vleft
--; i
++, min
++, max
++, first
=0) {
1994 if (len
> TMPBUFLEN
-1)
1996 if (copy_from_user(buf
, s
, len
))
2000 if (*p
== '-' && left
> 1) {
2004 if (*p
< '0' || *p
> '9')
2006 val
= simple_strtoul(p
, &p
, 0) * convmul
/ convdiv
;
2008 if ((len
< left
) && *p
&& !isspace(*p
))
2017 if ((min
&& val
< *min
) || (max
&& val
> *max
))
2024 sprintf(p
, "%lu", convdiv
* (*i
) / convmul
);
2028 if(copy_to_user(s
, buf
, len
))
2035 if (!write
&& !first
&& left
) {
2036 if(put_user('\n', s
))
2043 if (get_user(c
, s
++))
2058 static int do_proc_doulongvec_minmax(ctl_table
*table
, int write
,
2060 void __user
*buffer
,
2061 size_t *lenp
, loff_t
*ppos
,
2062 unsigned long convmul
,
2063 unsigned long convdiv
)
2065 return __do_proc_doulongvec_minmax(table
->data
, table
, write
,
2066 filp
, buffer
, lenp
, ppos
, convmul
, convdiv
);
2070 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2071 * @table: the sysctl table
2072 * @write: %TRUE if this is a write to the sysctl file
2073 * @filp: the file structure
2074 * @buffer: the user buffer
2075 * @lenp: the size of the user buffer
2076 * @ppos: file position
2078 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2079 * values from/to the user buffer, treated as an ASCII string.
2081 * This routine will ensure the values are within the range specified by
2082 * table->extra1 (min) and table->extra2 (max).
2084 * Returns 0 on success.
2086 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2087 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2089 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
, lenp
, ppos
, 1l, 1l);
2093 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2094 * @table: the sysctl table
2095 * @write: %TRUE if this is a write to the sysctl file
2096 * @filp: the file structure
2097 * @buffer: the user buffer
2098 * @lenp: the size of the user buffer
2099 * @ppos: file position
2101 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2102 * values from/to the user buffer, treated as an ASCII string. The values
2103 * are treated as milliseconds, and converted to jiffies when they are stored.
2105 * This routine will ensure the values are within the range specified by
2106 * table->extra1 (min) and table->extra2 (max).
2108 * Returns 0 on success.
2110 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2112 void __user
*buffer
,
2113 size_t *lenp
, loff_t
*ppos
)
2115 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
,
2116 lenp
, ppos
, HZ
, 1000l);
2120 static int do_proc_dointvec_jiffies_conv(int *negp
, unsigned long *lvalp
,
2122 int write
, void *data
)
2125 if (*lvalp
> LONG_MAX
/ HZ
)
2127 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2133 lval
= (unsigned long)-val
;
2136 lval
= (unsigned long)val
;
2143 static int do_proc_dointvec_userhz_jiffies_conv(int *negp
, unsigned long *lvalp
,
2145 int write
, void *data
)
2148 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2150 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2156 lval
= (unsigned long)-val
;
2159 lval
= (unsigned long)val
;
2161 *lvalp
= jiffies_to_clock_t(lval
);
2166 static int do_proc_dointvec_ms_jiffies_conv(int *negp
, unsigned long *lvalp
,
2168 int write
, void *data
)
2171 *valp
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2177 lval
= (unsigned long)-val
;
2180 lval
= (unsigned long)val
;
2182 *lvalp
= jiffies_to_msecs(lval
);
2188 * proc_dointvec_jiffies - read a vector of integers as seconds
2189 * @table: the sysctl table
2190 * @write: %TRUE if this is a write to the sysctl file
2191 * @filp: the file structure
2192 * @buffer: the user buffer
2193 * @lenp: the size of the user buffer
2194 * @ppos: file position
2196 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2197 * values from/to the user buffer, treated as an ASCII string.
2198 * The values read are assumed to be in seconds, and are converted into
2201 * Returns 0 on success.
2203 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2204 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2206 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2207 do_proc_dointvec_jiffies_conv
,NULL
);
2211 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2212 * @table: the sysctl table
2213 * @write: %TRUE if this is a write to the sysctl file
2214 * @filp: the file structure
2215 * @buffer: the user buffer
2216 * @lenp: the size of the user buffer
2217 * @ppos: pointer to the file position
2219 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2220 * values from/to the user buffer, treated as an ASCII string.
2221 * The values read are assumed to be in 1/USER_HZ seconds, and
2222 * are converted into jiffies.
2224 * Returns 0 on success.
2226 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2227 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2229 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2230 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2234 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2235 * @table: the sysctl table
2236 * @write: %TRUE if this is a write to the sysctl file
2237 * @filp: the file structure
2238 * @buffer: the user buffer
2239 * @lenp: the size of the user buffer
2240 * @ppos: file position
2241 * @ppos: the current position in the file
2243 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2244 * values from/to the user buffer, treated as an ASCII string.
2245 * The values read are assumed to be in 1/1000 seconds, and
2246 * are converted into jiffies.
2248 * Returns 0 on success.
2250 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2251 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2253 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2254 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2257 static int proc_do_cad_pid(ctl_table
*table
, int write
, struct file
*filp
,
2258 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2260 struct pid
*new_pid
;
2264 tmp
= pid_nr(cad_pid
);
2266 r
= __do_proc_dointvec(&tmp
, table
, write
, filp
, buffer
,
2267 lenp
, ppos
, NULL
, NULL
);
2271 new_pid
= find_get_pid(tmp
);
2275 put_pid(xchg(&cad_pid
, new_pid
));
2279 #else /* CONFIG_PROC_FS */
2281 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
2282 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2287 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
2288 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2293 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
2294 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2299 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2300 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2305 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2306 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2311 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2312 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2317 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2318 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2323 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2324 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2329 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2331 void __user
*buffer
,
2332 size_t *lenp
, loff_t
*ppos
)
2338 #endif /* CONFIG_PROC_FS */
2341 #ifdef CONFIG_SYSCTL_SYSCALL
2343 * General sysctl support routines
2346 /* The generic string strategy routine: */
2347 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2348 void __user
*oldval
, size_t __user
*oldlenp
,
2349 void __user
*newval
, size_t newlen
)
2351 if (!table
->data
|| !table
->maxlen
)
2354 if (oldval
&& oldlenp
) {
2356 if (get_user(bufsize
, oldlenp
))
2359 size_t len
= strlen(table
->data
), copied
;
2361 /* This shouldn't trigger for a well-formed sysctl */
2362 if (len
> table
->maxlen
)
2363 len
= table
->maxlen
;
2365 /* Copy up to a max of bufsize-1 bytes of the string */
2366 copied
= (len
>= bufsize
) ? bufsize
- 1 : len
;
2368 if (copy_to_user(oldval
, table
->data
, copied
) ||
2369 put_user(0, (char __user
*)(oldval
+ copied
)))
2371 if (put_user(len
, oldlenp
))
2375 if (newval
&& newlen
) {
2376 size_t len
= newlen
;
2377 if (len
> table
->maxlen
)
2378 len
= table
->maxlen
;
2379 if(copy_from_user(table
->data
, newval
, len
))
2381 if (len
== table
->maxlen
)
2383 ((char *) table
->data
)[len
] = 0;
2389 * This function makes sure that all of the integers in the vector
2390 * are between the minimum and maximum values given in the arrays
2391 * table->extra1 and table->extra2, respectively.
2393 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2394 void __user
*oldval
, size_t __user
*oldlenp
,
2395 void __user
*newval
, size_t newlen
)
2398 if (newval
&& newlen
) {
2399 int __user
*vec
= (int __user
*) newval
;
2400 int *min
= (int *) table
->extra1
;
2401 int *max
= (int *) table
->extra2
;
2405 if (newlen
% sizeof(int) != 0)
2408 if (!table
->extra1
&& !table
->extra2
)
2411 if (newlen
> table
->maxlen
)
2412 newlen
= table
->maxlen
;
2413 length
= newlen
/ sizeof(int);
2415 for (i
= 0; i
< length
; i
++) {
2417 if (get_user(value
, vec
+ i
))
2419 if (min
&& value
< min
[i
])
2421 if (max
&& value
> max
[i
])
2428 /* Strategy function to convert jiffies to seconds */
2429 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2430 void __user
*oldval
, size_t __user
*oldlenp
,
2431 void __user
*newval
, size_t newlen
)
2433 if (oldval
&& oldlenp
) {
2436 if (get_user(olen
, oldlenp
))
2441 if (olen
< sizeof(int))
2444 val
= *(int *)(table
->data
) / HZ
;
2445 if (put_user(val
, (int __user
*)oldval
))
2447 if (put_user(sizeof(int), oldlenp
))
2451 if (newval
&& newlen
) {
2453 if (newlen
!= sizeof(int))
2455 if (get_user(new, (int __user
*)newval
))
2457 *(int *)(table
->data
) = new*HZ
;
2462 /* Strategy function to convert jiffies to seconds */
2463 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2464 void __user
*oldval
, size_t __user
*oldlenp
,
2465 void __user
*newval
, size_t newlen
)
2467 if (oldval
&& oldlenp
) {
2470 if (get_user(olen
, oldlenp
))
2475 if (olen
< sizeof(int))
2478 val
= jiffies_to_msecs(*(int *)(table
->data
));
2479 if (put_user(val
, (int __user
*)oldval
))
2481 if (put_user(sizeof(int), oldlenp
))
2485 if (newval
&& newlen
) {
2487 if (newlen
!= sizeof(int))
2489 if (get_user(new, (int __user
*)newval
))
2491 *(int *)(table
->data
) = msecs_to_jiffies(new);
2498 #else /* CONFIG_SYSCTL_SYSCALL */
2501 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
2503 static int msg_count
;
2504 struct __sysctl_args tmp
;
2505 int name
[CTL_MAXNAME
];
2508 /* Read in the sysctl name for better debug message logging */
2509 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
2511 if (tmp
.nlen
<= 0 || tmp
.nlen
>= CTL_MAXNAME
)
2513 for (i
= 0; i
< tmp
.nlen
; i
++)
2514 if (get_user(name
[i
], tmp
.name
+ i
))
2517 /* Ignore accesses to kernel.version */
2518 if ((tmp
.nlen
== 2) && (name
[0] == CTL_KERN
) && (name
[1] == KERN_VERSION
))
2521 if (msg_count
< 5) {
2524 "warning: process `%s' used the removed sysctl "
2525 "system call with ", current
->comm
);
2526 for (i
= 0; i
< tmp
.nlen
; i
++)
2527 printk("%d.", name
[i
]);
2534 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2535 void __user
*oldval
, size_t __user
*oldlenp
,
2536 void __user
*newval
, size_t newlen
)
2541 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2542 void __user
*oldval
, size_t __user
*oldlenp
,
2543 void __user
*newval
, size_t newlen
)
2548 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2549 void __user
*oldval
, size_t __user
*oldlenp
,
2550 void __user
*newval
, size_t newlen
)
2555 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2556 void __user
*oldval
, size_t __user
*oldlenp
,
2557 void __user
*newval
, size_t newlen
)
2562 #endif /* CONFIG_SYSCTL_SYSCALL */
2565 * No sense putting this after each symbol definition, twice,
2566 * exception granted :-)
2568 EXPORT_SYMBOL(proc_dointvec
);
2569 EXPORT_SYMBOL(proc_dointvec_jiffies
);
2570 EXPORT_SYMBOL(proc_dointvec_minmax
);
2571 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
2572 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
2573 EXPORT_SYMBOL(proc_dostring
);
2574 EXPORT_SYMBOL(proc_doulongvec_minmax
);
2575 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);
2576 EXPORT_SYMBOL(register_sysctl_table
);
2577 EXPORT_SYMBOL(sysctl_intvec
);
2578 EXPORT_SYMBOL(sysctl_jiffies
);
2579 EXPORT_SYMBOL(sysctl_ms_jiffies
);
2580 EXPORT_SYMBOL(sysctl_string
);
2581 EXPORT_SYMBOL(unregister_sysctl_table
);