2 * sysctl.c: General linux system control interface
4 * Begun 24 March 1995, Stephen Tweedie
5 * Added /proc support, Dec 1995
6 * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
7 * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
8 * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
9 * Dynamic registration fixes, Stephen Tweedie.
10 * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
11 * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
13 * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
14 * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
15 * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
17 * The list_for_each() macro wasn't appropriate for the sysctl loop.
18 * Removed it and replaced it with older style, 03/23/00, Bill Wendling
21 #include <linux/module.h>
23 #include <linux/swap.h>
24 #include <linux/slab.h>
25 #include <linux/sysctl.h>
26 #include <linux/proc_fs.h>
27 #include <linux/capability.h>
28 #include <linux/ctype.h>
29 #include <linux/utsname.h>
30 #include <linux/capability.h>
31 #include <linux/smp_lock.h>
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>
49 #include <asm/uaccess.h>
50 #include <asm/processor.h>
52 extern int proc_nr_files(ctl_table
*table
, int write
, struct file
*filp
,
53 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
55 #if defined(CONFIG_SYSCTL)
57 /* External variables not in a header file. */
59 extern int sysctl_overcommit_memory
;
60 extern int sysctl_overcommit_ratio
;
61 extern int sysctl_panic_on_oom
;
62 extern int max_threads
;
63 extern int sysrq_enabled
;
64 extern int core_uses_pid
;
65 extern int suid_dumpable
;
66 extern char core_pattern
[];
69 extern int min_free_kbytes
;
70 extern int printk_ratelimit_jiffies
;
71 extern int printk_ratelimit_burst
;
72 extern int pid_max_min
, pid_max_max
;
73 extern int sysctl_drop_caches
;
74 extern int percpu_pagelist_fraction
;
75 extern int compat_log
;
77 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
78 int unknown_nmi_panic
;
79 extern int proc_unknown_nmi_panic(ctl_table
*, int, struct file
*,
80 void __user
*, size_t *, loff_t
*);
83 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
84 static int maxolduid
= 65535;
86 static int min_percpu_pagelist_fract
= 8;
88 static int ngroups_max
= NGROUPS_MAX
;
91 extern char modprobe_path
[];
93 #ifdef CONFIG_CHR_DEV_SG
94 extern int sg_big_buff
;
97 extern size_t shm_ctlmax
;
98 extern size_t shm_ctlall
;
99 extern int shm_ctlmni
;
100 extern int msg_ctlmax
;
101 extern int msg_ctlmnb
;
102 extern int msg_ctlmni
;
103 extern int sem_ctls
[];
107 extern char reboot_command
[];
108 extern int stop_a_enabled
;
109 extern int scons_pwroff
;
113 extern int pwrsw_enabled
;
114 extern int unaligned_enabled
;
118 #ifdef CONFIG_MATHEMU
119 extern int sysctl_ieee_emulation_warnings
;
121 extern int sysctl_userprocess_debug
;
122 extern int spin_retry
;
125 extern int sysctl_hz_timer
;
127 #ifdef CONFIG_BSD_PROCESS_ACCT
128 extern int acct_parm
[];
132 extern int no_unaligned_warning
;
135 #ifdef CONFIG_RT_MUTEXES
136 extern int max_lock_depth
;
139 static int parse_table(int __user
*, int, void __user
*, size_t __user
*, void __user
*, size_t,
140 ctl_table
*, void **);
141 static int proc_doutsstring(ctl_table
*table
, int write
, struct file
*filp
,
142 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
144 static ctl_table root_table
[];
145 static struct ctl_table_header root_table_header
=
146 { root_table
, LIST_HEAD_INIT(root_table_header
.ctl_entry
) };
148 static ctl_table kern_table
[];
149 static ctl_table vm_table
[];
150 static ctl_table fs_table
[];
151 static ctl_table debug_table
[];
152 static ctl_table dev_table
[];
153 extern ctl_table random_table
[];
154 #ifdef CONFIG_UNIX98_PTYS
155 extern ctl_table pty_table
[];
157 #ifdef CONFIG_INOTIFY_USER
158 extern ctl_table inotify_table
[];
161 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
162 int sysctl_legacy_va_layout
;
165 /* /proc declarations: */
167 #ifdef CONFIG_PROC_FS
169 static ssize_t
proc_readsys(struct file
*, char __user
*, size_t, loff_t
*);
170 static ssize_t
proc_writesys(struct file
*, const char __user
*, size_t, loff_t
*);
171 static int proc_opensys(struct inode
*, struct file
*);
173 struct file_operations proc_sys_file_operations
= {
174 .open
= proc_opensys
,
175 .read
= proc_readsys
,
176 .write
= proc_writesys
,
179 extern struct proc_dir_entry
*proc_sys_root
;
181 static void register_proc_table(ctl_table
*, struct proc_dir_entry
*, void *);
182 static void unregister_proc_table(ctl_table
*, struct proc_dir_entry
*);
185 /* The default sysctl tables: */
187 static ctl_table root_table
[] = {
189 .ctl_name
= CTL_KERN
,
190 .procname
= "kernel",
215 .ctl_name
= CTL_DEBUG
,
218 .child
= debug_table
,
230 static ctl_table kern_table
[] = {
232 .ctl_name
= KERN_OSTYPE
,
233 .procname
= "ostype",
234 .data
= system_utsname
.sysname
,
235 .maxlen
= sizeof(system_utsname
.sysname
),
237 .proc_handler
= &proc_doutsstring
,
238 .strategy
= &sysctl_string
,
241 .ctl_name
= KERN_OSRELEASE
,
242 .procname
= "osrelease",
243 .data
= system_utsname
.release
,
244 .maxlen
= sizeof(system_utsname
.release
),
246 .proc_handler
= &proc_doutsstring
,
247 .strategy
= &sysctl_string
,
250 .ctl_name
= KERN_VERSION
,
251 .procname
= "version",
252 .data
= system_utsname
.version
,
253 .maxlen
= sizeof(system_utsname
.version
),
255 .proc_handler
= &proc_doutsstring
,
256 .strategy
= &sysctl_string
,
259 .ctl_name
= KERN_NODENAME
,
260 .procname
= "hostname",
261 .data
= system_utsname
.nodename
,
262 .maxlen
= sizeof(system_utsname
.nodename
),
264 .proc_handler
= &proc_doutsstring
,
265 .strategy
= &sysctl_string
,
268 .ctl_name
= KERN_DOMAINNAME
,
269 .procname
= "domainname",
270 .data
= system_utsname
.domainname
,
271 .maxlen
= sizeof(system_utsname
.domainname
),
273 .proc_handler
= &proc_doutsstring
,
274 .strategy
= &sysctl_string
,
277 .ctl_name
= KERN_PANIC
,
279 .data
= &panic_timeout
,
280 .maxlen
= sizeof(int),
282 .proc_handler
= &proc_dointvec
,
285 .ctl_name
= KERN_CORE_USES_PID
,
286 .procname
= "core_uses_pid",
287 .data
= &core_uses_pid
,
288 .maxlen
= sizeof(int),
290 .proc_handler
= &proc_dointvec
,
293 .ctl_name
= KERN_CORE_PATTERN
,
294 .procname
= "core_pattern",
295 .data
= core_pattern
,
298 .proc_handler
= &proc_dostring
,
299 .strategy
= &sysctl_string
,
302 .ctl_name
= KERN_TAINTED
,
303 .procname
= "tainted",
305 .maxlen
= sizeof(int),
307 .proc_handler
= &proc_dointvec
,
310 .ctl_name
= KERN_CAP_BSET
,
311 .procname
= "cap-bound",
313 .maxlen
= sizeof(kernel_cap_t
),
315 .proc_handler
= &proc_dointvec_bset
,
317 #ifdef CONFIG_BLK_DEV_INITRD
319 .ctl_name
= KERN_REALROOTDEV
,
320 .procname
= "real-root-dev",
321 .data
= &real_root_dev
,
322 .maxlen
= sizeof(int),
324 .proc_handler
= &proc_dointvec
,
329 .ctl_name
= KERN_SPARC_REBOOT
,
330 .procname
= "reboot-cmd",
331 .data
= reboot_command
,
334 .proc_handler
= &proc_dostring
,
335 .strategy
= &sysctl_string
,
338 .ctl_name
= KERN_SPARC_STOP_A
,
339 .procname
= "stop-a",
340 .data
= &stop_a_enabled
,
341 .maxlen
= sizeof (int),
343 .proc_handler
= &proc_dointvec
,
346 .ctl_name
= KERN_SPARC_SCONS_PWROFF
,
347 .procname
= "scons-poweroff",
348 .data
= &scons_pwroff
,
349 .maxlen
= sizeof (int),
351 .proc_handler
= &proc_dointvec
,
356 .ctl_name
= KERN_HPPA_PWRSW
,
357 .procname
= "soft-power",
358 .data
= &pwrsw_enabled
,
359 .maxlen
= sizeof (int),
361 .proc_handler
= &proc_dointvec
,
364 .ctl_name
= KERN_HPPA_UNALIGNED
,
365 .procname
= "unaligned-trap",
366 .data
= &unaligned_enabled
,
367 .maxlen
= sizeof (int),
369 .proc_handler
= &proc_dointvec
,
373 .ctl_name
= KERN_CTLALTDEL
,
374 .procname
= "ctrl-alt-del",
376 .maxlen
= sizeof(int),
378 .proc_handler
= &proc_dointvec
,
381 .ctl_name
= KERN_PRINTK
,
382 .procname
= "printk",
383 .data
= &console_loglevel
,
384 .maxlen
= 4*sizeof(int),
386 .proc_handler
= &proc_dointvec
,
390 .ctl_name
= KERN_MODPROBE
,
391 .procname
= "modprobe",
392 .data
= &modprobe_path
,
393 .maxlen
= KMOD_PATH_LEN
,
395 .proc_handler
= &proc_dostring
,
396 .strategy
= &sysctl_string
,
399 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
401 .ctl_name
= KERN_HOTPLUG
,
402 .procname
= "hotplug",
403 .data
= &uevent_helper
,
404 .maxlen
= UEVENT_HELPER_PATH_LEN
,
406 .proc_handler
= &proc_dostring
,
407 .strategy
= &sysctl_string
,
410 #ifdef CONFIG_CHR_DEV_SG
412 .ctl_name
= KERN_SG_BIG_BUFF
,
413 .procname
= "sg-big-buff",
414 .data
= &sg_big_buff
,
415 .maxlen
= sizeof (int),
417 .proc_handler
= &proc_dointvec
,
420 #ifdef CONFIG_BSD_PROCESS_ACCT
422 .ctl_name
= KERN_ACCT
,
425 .maxlen
= 3*sizeof(int),
427 .proc_handler
= &proc_dointvec
,
430 #ifdef CONFIG_SYSVIPC
432 .ctl_name
= KERN_SHMMAX
,
433 .procname
= "shmmax",
435 .maxlen
= sizeof (size_t),
437 .proc_handler
= &proc_doulongvec_minmax
,
440 .ctl_name
= KERN_SHMALL
,
441 .procname
= "shmall",
443 .maxlen
= sizeof (size_t),
445 .proc_handler
= &proc_doulongvec_minmax
,
448 .ctl_name
= KERN_SHMMNI
,
449 .procname
= "shmmni",
451 .maxlen
= sizeof (int),
453 .proc_handler
= &proc_dointvec
,
456 .ctl_name
= KERN_MSGMAX
,
457 .procname
= "msgmax",
459 .maxlen
= sizeof (int),
461 .proc_handler
= &proc_dointvec
,
464 .ctl_name
= KERN_MSGMNI
,
465 .procname
= "msgmni",
467 .maxlen
= sizeof (int),
469 .proc_handler
= &proc_dointvec
,
472 .ctl_name
= KERN_MSGMNB
,
473 .procname
= "msgmnb",
475 .maxlen
= sizeof (int),
477 .proc_handler
= &proc_dointvec
,
480 .ctl_name
= KERN_SEM
,
483 .maxlen
= 4*sizeof (int),
485 .proc_handler
= &proc_dointvec
,
488 #ifdef CONFIG_MAGIC_SYSRQ
490 .ctl_name
= KERN_SYSRQ
,
492 .data
= &sysrq_enabled
,
493 .maxlen
= sizeof (int),
495 .proc_handler
= &proc_dointvec
,
499 .ctl_name
= KERN_CADPID
,
500 .procname
= "cad_pid",
502 .maxlen
= sizeof (int),
504 .proc_handler
= &proc_dointvec
,
507 .ctl_name
= KERN_MAX_THREADS
,
508 .procname
= "threads-max",
509 .data
= &max_threads
,
510 .maxlen
= sizeof(int),
512 .proc_handler
= &proc_dointvec
,
515 .ctl_name
= KERN_RANDOM
,
516 .procname
= "random",
518 .child
= random_table
,
520 #ifdef CONFIG_UNIX98_PTYS
522 .ctl_name
= KERN_PTY
,
529 .ctl_name
= KERN_OVERFLOWUID
,
530 .procname
= "overflowuid",
531 .data
= &overflowuid
,
532 .maxlen
= sizeof(int),
534 .proc_handler
= &proc_dointvec_minmax
,
535 .strategy
= &sysctl_intvec
,
536 .extra1
= &minolduid
,
537 .extra2
= &maxolduid
,
540 .ctl_name
= KERN_OVERFLOWGID
,
541 .procname
= "overflowgid",
542 .data
= &overflowgid
,
543 .maxlen
= sizeof(int),
545 .proc_handler
= &proc_dointvec_minmax
,
546 .strategy
= &sysctl_intvec
,
547 .extra1
= &minolduid
,
548 .extra2
= &maxolduid
,
551 #ifdef CONFIG_MATHEMU
553 .ctl_name
= KERN_IEEE_EMULATION_WARNINGS
,
554 .procname
= "ieee_emulation_warnings",
555 .data
= &sysctl_ieee_emulation_warnings
,
556 .maxlen
= sizeof(int),
558 .proc_handler
= &proc_dointvec
,
561 #ifdef CONFIG_NO_IDLE_HZ
563 .ctl_name
= KERN_HZ_TIMER
,
564 .procname
= "hz_timer",
565 .data
= &sysctl_hz_timer
,
566 .maxlen
= sizeof(int),
568 .proc_handler
= &proc_dointvec
,
572 .ctl_name
= KERN_S390_USER_DEBUG_LOGGING
,
573 .procname
= "userprocess_debug",
574 .data
= &sysctl_userprocess_debug
,
575 .maxlen
= sizeof(int),
577 .proc_handler
= &proc_dointvec
,
581 .ctl_name
= KERN_PIDMAX
,
582 .procname
= "pid_max",
584 .maxlen
= sizeof (int),
586 .proc_handler
= &proc_dointvec_minmax
,
587 .strategy
= sysctl_intvec
,
588 .extra1
= &pid_max_min
,
589 .extra2
= &pid_max_max
,
592 .ctl_name
= KERN_PANIC_ON_OOPS
,
593 .procname
= "panic_on_oops",
594 .data
= &panic_on_oops
,
595 .maxlen
= sizeof(int),
597 .proc_handler
= &proc_dointvec
,
600 .ctl_name
= KERN_PRINTK_RATELIMIT
,
601 .procname
= "printk_ratelimit",
602 .data
= &printk_ratelimit_jiffies
,
603 .maxlen
= sizeof(int),
605 .proc_handler
= &proc_dointvec_jiffies
,
606 .strategy
= &sysctl_jiffies
,
609 .ctl_name
= KERN_PRINTK_RATELIMIT_BURST
,
610 .procname
= "printk_ratelimit_burst",
611 .data
= &printk_ratelimit_burst
,
612 .maxlen
= sizeof(int),
614 .proc_handler
= &proc_dointvec
,
617 .ctl_name
= KERN_NGROUPS_MAX
,
618 .procname
= "ngroups_max",
619 .data
= &ngroups_max
,
620 .maxlen
= sizeof (int),
622 .proc_handler
= &proc_dointvec
,
624 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
626 .ctl_name
= KERN_UNKNOWN_NMI_PANIC
,
627 .procname
= "unknown_nmi_panic",
628 .data
= &unknown_nmi_panic
,
629 .maxlen
= sizeof (int),
631 .proc_handler
= &proc_unknown_nmi_panic
,
634 #if defined(CONFIG_X86)
636 .ctl_name
= KERN_BOOTLOADER_TYPE
,
637 .procname
= "bootloader_type",
638 .data
= &bootloader_type
,
639 .maxlen
= sizeof (int),
641 .proc_handler
= &proc_dointvec
,
644 #if defined(CONFIG_MMU)
646 .ctl_name
= KERN_RANDOMIZE
,
647 .procname
= "randomize_va_space",
648 .data
= &randomize_va_space
,
649 .maxlen
= sizeof(int),
651 .proc_handler
= &proc_dointvec
,
654 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
656 .ctl_name
= KERN_SPIN_RETRY
,
657 .procname
= "spin_retry",
659 .maxlen
= sizeof (int),
661 .proc_handler
= &proc_dointvec
,
664 #ifdef CONFIG_ACPI_SLEEP
666 .ctl_name
= KERN_ACPI_VIDEO_FLAGS
,
667 .procname
= "acpi_video_flags",
668 .data
= &acpi_video_flags
,
669 .maxlen
= sizeof (unsigned long),
671 .proc_handler
= &proc_doulongvec_minmax
,
676 .ctl_name
= KERN_IA64_UNALIGNED
,
677 .procname
= "ignore-unaligned-usertrap",
678 .data
= &no_unaligned_warning
,
679 .maxlen
= sizeof (int),
681 .proc_handler
= &proc_dointvec
,
686 .ctl_name
= KERN_COMPAT_LOG
,
687 .procname
= "compat-log",
689 .maxlen
= sizeof (int),
691 .proc_handler
= &proc_dointvec
,
694 #ifdef CONFIG_RT_MUTEXES
696 .ctl_name
= KERN_MAX_LOCK_DEPTH
,
697 .procname
= "max_lock_depth",
698 .data
= &max_lock_depth
,
699 .maxlen
= sizeof(int),
701 .proc_handler
= &proc_dointvec
,
708 /* Constants for minimum and maximum testing in vm_table.
709 We use these as one-element integer vectors. */
711 static int one_hundred
= 100;
714 static ctl_table vm_table
[] = {
716 .ctl_name
= VM_OVERCOMMIT_MEMORY
,
717 .procname
= "overcommit_memory",
718 .data
= &sysctl_overcommit_memory
,
719 .maxlen
= sizeof(sysctl_overcommit_memory
),
721 .proc_handler
= &proc_dointvec
,
724 .ctl_name
= VM_PANIC_ON_OOM
,
725 .procname
= "panic_on_oom",
726 .data
= &sysctl_panic_on_oom
,
727 .maxlen
= sizeof(sysctl_panic_on_oom
),
729 .proc_handler
= &proc_dointvec
,
732 .ctl_name
= VM_OVERCOMMIT_RATIO
,
733 .procname
= "overcommit_ratio",
734 .data
= &sysctl_overcommit_ratio
,
735 .maxlen
= sizeof(sysctl_overcommit_ratio
),
737 .proc_handler
= &proc_dointvec
,
740 .ctl_name
= VM_PAGE_CLUSTER
,
741 .procname
= "page-cluster",
742 .data
= &page_cluster
,
743 .maxlen
= sizeof(int),
745 .proc_handler
= &proc_dointvec
,
748 .ctl_name
= VM_DIRTY_BACKGROUND
,
749 .procname
= "dirty_background_ratio",
750 .data
= &dirty_background_ratio
,
751 .maxlen
= sizeof(dirty_background_ratio
),
753 .proc_handler
= &proc_dointvec_minmax
,
754 .strategy
= &sysctl_intvec
,
756 .extra2
= &one_hundred
,
759 .ctl_name
= VM_DIRTY_RATIO
,
760 .procname
= "dirty_ratio",
761 .data
= &vm_dirty_ratio
,
762 .maxlen
= sizeof(vm_dirty_ratio
),
764 .proc_handler
= &proc_dointvec_minmax
,
765 .strategy
= &sysctl_intvec
,
767 .extra2
= &one_hundred
,
770 .ctl_name
= VM_DIRTY_WB_CS
,
771 .procname
= "dirty_writeback_centisecs",
772 .data
= &dirty_writeback_interval
,
773 .maxlen
= sizeof(dirty_writeback_interval
),
775 .proc_handler
= &dirty_writeback_centisecs_handler
,
778 .ctl_name
= VM_DIRTY_EXPIRE_CS
,
779 .procname
= "dirty_expire_centisecs",
780 .data
= &dirty_expire_interval
,
781 .maxlen
= sizeof(dirty_expire_interval
),
783 .proc_handler
= &proc_dointvec_userhz_jiffies
,
786 .ctl_name
= VM_NR_PDFLUSH_THREADS
,
787 .procname
= "nr_pdflush_threads",
788 .data
= &nr_pdflush_threads
,
789 .maxlen
= sizeof nr_pdflush_threads
,
790 .mode
= 0444 /* read-only*/,
791 .proc_handler
= &proc_dointvec
,
794 .ctl_name
= VM_SWAPPINESS
,
795 .procname
= "swappiness",
796 .data
= &vm_swappiness
,
797 .maxlen
= sizeof(vm_swappiness
),
799 .proc_handler
= &proc_dointvec_minmax
,
800 .strategy
= &sysctl_intvec
,
802 .extra2
= &one_hundred
,
804 #ifdef CONFIG_HUGETLB_PAGE
806 .ctl_name
= VM_HUGETLB_PAGES
,
807 .procname
= "nr_hugepages",
808 .data
= &max_huge_pages
,
809 .maxlen
= sizeof(unsigned long),
811 .proc_handler
= &hugetlb_sysctl_handler
,
812 .extra1
= (void *)&hugetlb_zero
,
813 .extra2
= (void *)&hugetlb_infinity
,
816 .ctl_name
= VM_HUGETLB_GROUP
,
817 .procname
= "hugetlb_shm_group",
818 .data
= &sysctl_hugetlb_shm_group
,
819 .maxlen
= sizeof(gid_t
),
821 .proc_handler
= &proc_dointvec
,
825 .ctl_name
= VM_LOWMEM_RESERVE_RATIO
,
826 .procname
= "lowmem_reserve_ratio",
827 .data
= &sysctl_lowmem_reserve_ratio
,
828 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
830 .proc_handler
= &lowmem_reserve_ratio_sysctl_handler
,
831 .strategy
= &sysctl_intvec
,
834 .ctl_name
= VM_DROP_PAGECACHE
,
835 .procname
= "drop_caches",
836 .data
= &sysctl_drop_caches
,
837 .maxlen
= sizeof(int),
839 .proc_handler
= drop_caches_sysctl_handler
,
840 .strategy
= &sysctl_intvec
,
843 .ctl_name
= VM_MIN_FREE_KBYTES
,
844 .procname
= "min_free_kbytes",
845 .data
= &min_free_kbytes
,
846 .maxlen
= sizeof(min_free_kbytes
),
848 .proc_handler
= &min_free_kbytes_sysctl_handler
,
849 .strategy
= &sysctl_intvec
,
853 .ctl_name
= VM_PERCPU_PAGELIST_FRACTION
,
854 .procname
= "percpu_pagelist_fraction",
855 .data
= &percpu_pagelist_fraction
,
856 .maxlen
= sizeof(percpu_pagelist_fraction
),
858 .proc_handler
= &percpu_pagelist_fraction_sysctl_handler
,
859 .strategy
= &sysctl_intvec
,
860 .extra1
= &min_percpu_pagelist_fract
,
864 .ctl_name
= VM_MAX_MAP_COUNT
,
865 .procname
= "max_map_count",
866 .data
= &sysctl_max_map_count
,
867 .maxlen
= sizeof(sysctl_max_map_count
),
869 .proc_handler
= &proc_dointvec
873 .ctl_name
= VM_LAPTOP_MODE
,
874 .procname
= "laptop_mode",
875 .data
= &laptop_mode
,
876 .maxlen
= sizeof(laptop_mode
),
878 .proc_handler
= &proc_dointvec_jiffies
,
879 .strategy
= &sysctl_jiffies
,
882 .ctl_name
= VM_BLOCK_DUMP
,
883 .procname
= "block_dump",
885 .maxlen
= sizeof(block_dump
),
887 .proc_handler
= &proc_dointvec
,
888 .strategy
= &sysctl_intvec
,
892 .ctl_name
= VM_VFS_CACHE_PRESSURE
,
893 .procname
= "vfs_cache_pressure",
894 .data
= &sysctl_vfs_cache_pressure
,
895 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
897 .proc_handler
= &proc_dointvec
,
898 .strategy
= &sysctl_intvec
,
901 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
903 .ctl_name
= VM_LEGACY_VA_LAYOUT
,
904 .procname
= "legacy_va_layout",
905 .data
= &sysctl_legacy_va_layout
,
906 .maxlen
= sizeof(sysctl_legacy_va_layout
),
908 .proc_handler
= &proc_dointvec
,
909 .strategy
= &sysctl_intvec
,
915 .ctl_name
= VM_SWAP_TOKEN_TIMEOUT
,
916 .procname
= "swap_token_timeout",
917 .data
= &swap_token_default_timeout
,
918 .maxlen
= sizeof(swap_token_default_timeout
),
920 .proc_handler
= &proc_dointvec_jiffies
,
921 .strategy
= &sysctl_jiffies
,
926 .ctl_name
= VM_ZONE_RECLAIM_MODE
,
927 .procname
= "zone_reclaim_mode",
928 .data
= &zone_reclaim_mode
,
929 .maxlen
= sizeof(zone_reclaim_mode
),
931 .proc_handler
= &proc_dointvec
,
932 .strategy
= &sysctl_intvec
,
936 .ctl_name
= VM_MIN_UNMAPPED
,
937 .procname
= "min_unmapped_ratio",
938 .data
= &sysctl_min_unmapped_ratio
,
939 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
941 .proc_handler
= &sysctl_min_unmapped_ratio_sysctl_handler
,
942 .strategy
= &sysctl_intvec
,
944 .extra2
= &one_hundred
,
947 .ctl_name
= VM_MIN_SLAB
,
948 .procname
= "min_slab_ratio",
949 .data
= &sysctl_min_slab_ratio
,
950 .maxlen
= sizeof(sysctl_min_slab_ratio
),
952 .proc_handler
= &sysctl_min_slab_ratio_sysctl_handler
,
953 .strategy
= &sysctl_intvec
,
955 .extra2
= &one_hundred
,
960 .ctl_name
= VM_VDSO_ENABLED
,
961 .procname
= "vdso_enabled",
962 .data
= &vdso_enabled
,
963 .maxlen
= sizeof(vdso_enabled
),
965 .proc_handler
= &proc_dointvec
,
966 .strategy
= &sysctl_intvec
,
973 static ctl_table fs_table
[] = {
975 .ctl_name
= FS_NRINODE
,
976 .procname
= "inode-nr",
977 .data
= &inodes_stat
,
978 .maxlen
= 2*sizeof(int),
980 .proc_handler
= &proc_dointvec
,
983 .ctl_name
= FS_STATINODE
,
984 .procname
= "inode-state",
985 .data
= &inodes_stat
,
986 .maxlen
= 7*sizeof(int),
988 .proc_handler
= &proc_dointvec
,
991 .ctl_name
= FS_NRFILE
,
992 .procname
= "file-nr",
994 .maxlen
= 3*sizeof(int),
996 .proc_handler
= &proc_nr_files
,
999 .ctl_name
= FS_MAXFILE
,
1000 .procname
= "file-max",
1001 .data
= &files_stat
.max_files
,
1002 .maxlen
= sizeof(int),
1004 .proc_handler
= &proc_dointvec
,
1007 .ctl_name
= FS_DENTRY
,
1008 .procname
= "dentry-state",
1009 .data
= &dentry_stat
,
1010 .maxlen
= 6*sizeof(int),
1012 .proc_handler
= &proc_dointvec
,
1015 .ctl_name
= FS_OVERFLOWUID
,
1016 .procname
= "overflowuid",
1017 .data
= &fs_overflowuid
,
1018 .maxlen
= sizeof(int),
1020 .proc_handler
= &proc_dointvec_minmax
,
1021 .strategy
= &sysctl_intvec
,
1022 .extra1
= &minolduid
,
1023 .extra2
= &maxolduid
,
1026 .ctl_name
= FS_OVERFLOWGID
,
1027 .procname
= "overflowgid",
1028 .data
= &fs_overflowgid
,
1029 .maxlen
= sizeof(int),
1031 .proc_handler
= &proc_dointvec_minmax
,
1032 .strategy
= &sysctl_intvec
,
1033 .extra1
= &minolduid
,
1034 .extra2
= &maxolduid
,
1037 .ctl_name
= FS_LEASES
,
1038 .procname
= "leases-enable",
1039 .data
= &leases_enable
,
1040 .maxlen
= sizeof(int),
1042 .proc_handler
= &proc_dointvec
,
1044 #ifdef CONFIG_DNOTIFY
1046 .ctl_name
= FS_DIR_NOTIFY
,
1047 .procname
= "dir-notify-enable",
1048 .data
= &dir_notify_enable
,
1049 .maxlen
= sizeof(int),
1051 .proc_handler
= &proc_dointvec
,
1056 .ctl_name
= FS_LEASE_TIME
,
1057 .procname
= "lease-break-time",
1058 .data
= &lease_break_time
,
1059 .maxlen
= sizeof(int),
1061 .proc_handler
= &proc_dointvec
,
1064 .ctl_name
= FS_AIO_NR
,
1065 .procname
= "aio-nr",
1067 .maxlen
= sizeof(aio_nr
),
1069 .proc_handler
= &proc_doulongvec_minmax
,
1072 .ctl_name
= FS_AIO_MAX_NR
,
1073 .procname
= "aio-max-nr",
1074 .data
= &aio_max_nr
,
1075 .maxlen
= sizeof(aio_max_nr
),
1077 .proc_handler
= &proc_doulongvec_minmax
,
1079 #ifdef CONFIG_INOTIFY_USER
1081 .ctl_name
= FS_INOTIFY
,
1082 .procname
= "inotify",
1084 .child
= inotify_table
,
1089 .ctl_name
= KERN_SETUID_DUMPABLE
,
1090 .procname
= "suid_dumpable",
1091 .data
= &suid_dumpable
,
1092 .maxlen
= sizeof(int),
1094 .proc_handler
= &proc_dointvec
,
1099 static ctl_table debug_table
[] = {
1103 static ctl_table dev_table
[] = {
1107 extern void init_irq_proc (void);
1109 static DEFINE_SPINLOCK(sysctl_lock
);
1111 /* called under sysctl_lock */
1112 static int use_table(struct ctl_table_header
*p
)
1114 if (unlikely(p
->unregistering
))
1120 /* called under sysctl_lock */
1121 static void unuse_table(struct ctl_table_header
*p
)
1124 if (unlikely(p
->unregistering
))
1125 complete(p
->unregistering
);
1128 /* called under sysctl_lock, will reacquire if has to wait */
1129 static void start_unregistering(struct ctl_table_header
*p
)
1132 * if p->used is 0, nobody will ever touch that entry again;
1133 * we'll eliminate all paths to it before dropping sysctl_lock
1135 if (unlikely(p
->used
)) {
1136 struct completion wait
;
1137 init_completion(&wait
);
1138 p
->unregistering
= &wait
;
1139 spin_unlock(&sysctl_lock
);
1140 wait_for_completion(&wait
);
1141 spin_lock(&sysctl_lock
);
1144 * do not remove from the list until nobody holds it; walking the
1145 * list in do_sysctl() relies on that.
1147 list_del_init(&p
->ctl_entry
);
1150 void __init
sysctl_init(void)
1152 #ifdef CONFIG_PROC_FS
1153 register_proc_table(root_table
, proc_sys_root
, &root_table_header
);
1158 int do_sysctl(int __user
*name
, int nlen
, void __user
*oldval
, size_t __user
*oldlenp
,
1159 void __user
*newval
, size_t newlen
)
1161 struct list_head
*tmp
;
1162 int error
= -ENOTDIR
;
1164 if (nlen
<= 0 || nlen
>= CTL_MAXNAME
)
1168 if (!oldlenp
|| get_user(old_len
, oldlenp
))
1171 spin_lock(&sysctl_lock
);
1172 tmp
= &root_table_header
.ctl_entry
;
1174 struct ctl_table_header
*head
=
1175 list_entry(tmp
, struct ctl_table_header
, ctl_entry
);
1176 void *context
= NULL
;
1178 if (!use_table(head
))
1181 spin_unlock(&sysctl_lock
);
1183 error
= parse_table(name
, nlen
, oldval
, oldlenp
,
1184 newval
, newlen
, head
->ctl_table
,
1188 spin_lock(&sysctl_lock
);
1190 if (error
!= -ENOTDIR
)
1192 } while ((tmp
= tmp
->next
) != &root_table_header
.ctl_entry
);
1193 spin_unlock(&sysctl_lock
);
1197 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
1199 struct __sysctl_args tmp
;
1202 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
1206 error
= do_sysctl(tmp
.name
, tmp
.nlen
, tmp
.oldval
, tmp
.oldlenp
,
1207 tmp
.newval
, tmp
.newlen
);
1213 * ctl_perm does NOT grant the superuser all rights automatically, because
1214 * some sysctl variables are readonly even to root.
1217 static int test_perm(int mode
, int op
)
1221 else if (in_egroup_p(0))
1223 if ((mode
& op
& 0007) == op
)
1228 static inline int ctl_perm(ctl_table
*table
, int op
)
1231 error
= security_sysctl(table
, op
);
1234 return test_perm(table
->mode
, op
);
1237 static int parse_table(int __user
*name
, int nlen
,
1238 void __user
*oldval
, size_t __user
*oldlenp
,
1239 void __user
*newval
, size_t newlen
,
1240 ctl_table
*table
, void **context
)
1246 if (get_user(n
, name
))
1248 for ( ; table
->ctl_name
; table
++) {
1249 if (n
== table
->ctl_name
|| table
->ctl_name
== CTL_ANY
) {
1252 if (ctl_perm(table
, 001))
1254 if (table
->strategy
) {
1255 error
= table
->strategy(
1258 newval
, newlen
, context
);
1264 table
= table
->child
;
1267 error
= do_sysctl_strategy(table
, name
, nlen
,
1269 newval
, newlen
, context
);
1276 /* Perform the actual read/write of a sysctl table entry. */
1277 int do_sysctl_strategy (ctl_table
*table
,
1278 int __user
*name
, int nlen
,
1279 void __user
*oldval
, size_t __user
*oldlenp
,
1280 void __user
*newval
, size_t newlen
, void **context
)
1289 if (ctl_perm(table
, op
))
1292 if (table
->strategy
) {
1293 rc
= table
->strategy(table
, name
, nlen
, oldval
, oldlenp
,
1294 newval
, newlen
, context
);
1301 /* If there is no strategy routine, or if the strategy returns
1302 * zero, proceed with automatic r/w */
1303 if (table
->data
&& table
->maxlen
) {
1304 if (oldval
&& oldlenp
) {
1305 if (get_user(len
, oldlenp
))
1308 if (len
> table
->maxlen
)
1309 len
= table
->maxlen
;
1310 if(copy_to_user(oldval
, table
->data
, len
))
1312 if(put_user(len
, oldlenp
))
1316 if (newval
&& newlen
) {
1318 if (len
> table
->maxlen
)
1319 len
= table
->maxlen
;
1320 if(copy_from_user(table
->data
, newval
, len
))
1328 * register_sysctl_table - register a sysctl hierarchy
1329 * @table: the top-level table structure
1330 * @insert_at_head: whether the entry should be inserted in front or at the end
1332 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1333 * array. An entry with a ctl_name of 0 terminates the table.
1335 * The members of the &ctl_table structure are used as follows:
1337 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1338 * must be unique within that level of sysctl
1340 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1341 * enter a sysctl file
1343 * data - a pointer to data for use by proc_handler
1345 * maxlen - the maximum size in bytes of the data
1347 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1349 * child - a pointer to the child sysctl table if this entry is a directory, or
1352 * proc_handler - the text handler routine (described below)
1354 * strategy - the strategy routine (described below)
1356 * de - for internal use by the sysctl routines
1358 * extra1, extra2 - extra pointers usable by the proc handler routines
1360 * Leaf nodes in the sysctl tree will be represented by a single file
1361 * under /proc; non-leaf nodes will be represented by directories.
1363 * sysctl(2) can automatically manage read and write requests through
1364 * the sysctl table. The data and maxlen fields of the ctl_table
1365 * struct enable minimal validation of the values being written to be
1366 * performed, and the mode field allows minimal authentication.
1368 * More sophisticated management can be enabled by the provision of a
1369 * strategy routine with the table entry. This will be called before
1370 * any automatic read or write of the data is performed.
1372 * The strategy routine may return
1374 * < 0 - Error occurred (error is passed to user process)
1376 * 0 - OK - proceed with automatic read or write.
1378 * > 0 - OK - read or write has been done by the strategy routine, so
1379 * return immediately.
1381 * There must be a proc_handler routine for any terminal nodes
1382 * mirrored under /proc/sys (non-terminals are handled by a built-in
1383 * directory handler). Several default handlers are available to
1384 * cover common cases -
1386 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1387 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1388 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1390 * It is the handler's job to read the input buffer from user memory
1391 * and process it. The handler should return 0 on success.
1393 * This routine returns %NULL on a failure to register, and a pointer
1394 * to the table header on success.
1396 struct ctl_table_header
*register_sysctl_table(ctl_table
* table
,
1399 struct ctl_table_header
*tmp
;
1400 tmp
= kmalloc(sizeof(struct ctl_table_header
), GFP_KERNEL
);
1403 tmp
->ctl_table
= table
;
1404 INIT_LIST_HEAD(&tmp
->ctl_entry
);
1406 tmp
->unregistering
= NULL
;
1407 spin_lock(&sysctl_lock
);
1409 list_add(&tmp
->ctl_entry
, &root_table_header
.ctl_entry
);
1411 list_add_tail(&tmp
->ctl_entry
, &root_table_header
.ctl_entry
);
1412 spin_unlock(&sysctl_lock
);
1413 #ifdef CONFIG_PROC_FS
1414 register_proc_table(table
, proc_sys_root
, tmp
);
1420 * unregister_sysctl_table - unregister a sysctl table hierarchy
1421 * @header: the header returned from register_sysctl_table
1423 * Unregisters the sysctl table and all children. proc entries may not
1424 * actually be removed until they are no longer used by anyone.
1426 void unregister_sysctl_table(struct ctl_table_header
* header
)
1429 spin_lock(&sysctl_lock
);
1430 start_unregistering(header
);
1431 #ifdef CONFIG_PROC_FS
1432 unregister_proc_table(header
->ctl_table
, proc_sys_root
);
1434 spin_unlock(&sysctl_lock
);
1442 #ifdef CONFIG_PROC_FS
1444 /* Scan the sysctl entries in table and add them all into /proc */
1445 static void register_proc_table(ctl_table
* table
, struct proc_dir_entry
*root
, void *set
)
1447 struct proc_dir_entry
*de
;
1451 for (; table
->ctl_name
; table
++) {
1452 /* Can't do anything without a proc name. */
1453 if (!table
->procname
)
1455 /* Maybe we can't do anything with it... */
1456 if (!table
->proc_handler
&& !table
->child
) {
1457 printk(KERN_WARNING
"SYSCTL: Can't register %s\n",
1462 len
= strlen(table
->procname
);
1466 if (table
->proc_handler
)
1470 for (de
= root
->subdir
; de
; de
= de
->next
) {
1471 if (proc_match(len
, table
->procname
, de
))
1474 /* If the subdir exists already, de is non-NULL */
1478 de
= create_proc_entry(table
->procname
, mode
, root
);
1482 de
->data
= (void *) table
;
1483 if (table
->proc_handler
)
1484 de
->proc_fops
= &proc_sys_file_operations
;
1487 if (de
->mode
& S_IFDIR
)
1488 register_proc_table(table
->child
, de
, set
);
1493 * Unregister a /proc sysctl table and any subdirectories.
1495 static void unregister_proc_table(ctl_table
* table
, struct proc_dir_entry
*root
)
1497 struct proc_dir_entry
*de
;
1498 for (; table
->ctl_name
; table
++) {
1499 if (!(de
= table
->de
))
1501 if (de
->mode
& S_IFDIR
) {
1502 if (!table
->child
) {
1503 printk (KERN_ALERT
"Help - malformed sysctl tree on free\n");
1506 unregister_proc_table(table
->child
, de
);
1508 /* Don't unregister directories which still have entries.. */
1514 * In any case, mark the entry as goner; we'll keep it
1515 * around if it's busy, but we'll know to do nothing with
1516 * its fields. We are under sysctl_lock here.
1520 /* Don't unregister proc entries that are still being used.. */
1521 if (atomic_read(&de
->count
))
1525 remove_proc_entry(table
->procname
, root
);
1529 static ssize_t
do_rw_proc(int write
, struct file
* file
, char __user
* buf
,
1530 size_t count
, loff_t
*ppos
)
1533 struct proc_dir_entry
*de
= PDE(file
->f_dentry
->d_inode
);
1534 struct ctl_table
*table
;
1536 ssize_t error
= -ENOTDIR
;
1538 spin_lock(&sysctl_lock
);
1539 if (de
&& de
->data
&& use_table(de
->set
)) {
1541 * at that point we know that sysctl was not unregistered
1542 * and won't be until we finish
1544 spin_unlock(&sysctl_lock
);
1545 table
= (struct ctl_table
*) de
->data
;
1546 if (!table
|| !table
->proc_handler
)
1549 op
= (write
? 002 : 004);
1550 if (ctl_perm(table
, op
))
1553 /* careful: calling conventions are nasty here */
1555 error
= (*table
->proc_handler
)(table
, write
, file
,
1560 spin_lock(&sysctl_lock
);
1561 unuse_table(de
->set
);
1563 spin_unlock(&sysctl_lock
);
1567 static int proc_opensys(struct inode
*inode
, struct file
*file
)
1569 if (file
->f_mode
& FMODE_WRITE
) {
1571 * sysctl entries that are not writable,
1572 * are _NOT_ writable, capabilities or not.
1574 if (!(inode
->i_mode
& S_IWUSR
))
1581 static ssize_t
proc_readsys(struct file
* file
, char __user
* buf
,
1582 size_t count
, loff_t
*ppos
)
1584 return do_rw_proc(0, file
, buf
, count
, ppos
);
1587 static ssize_t
proc_writesys(struct file
* file
, const char __user
* buf
,
1588 size_t count
, loff_t
*ppos
)
1590 return do_rw_proc(1, file
, (char __user
*) buf
, count
, ppos
);
1594 * proc_dostring - read a string sysctl
1595 * @table: the sysctl table
1596 * @write: %TRUE if this is a write to the sysctl file
1597 * @filp: the file structure
1598 * @buffer: the user buffer
1599 * @lenp: the size of the user buffer
1600 * @ppos: file position
1602 * Reads/writes a string from/to the user buffer. If the kernel
1603 * buffer provided is not large enough to hold the string, the
1604 * string is truncated. The copied string is %NULL-terminated.
1605 * If the string is being read by the user process, it is copied
1606 * and a newline '\n' is added. It is truncated if the buffer is
1609 * Returns 0 on success.
1611 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
1612 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1618 if (!table
->data
|| !table
->maxlen
|| !*lenp
||
1619 (*ppos
&& !write
)) {
1627 while (len
< *lenp
) {
1628 if (get_user(c
, p
++))
1630 if (c
== 0 || c
== '\n')
1634 if (len
>= table
->maxlen
)
1635 len
= table
->maxlen
-1;
1636 if(copy_from_user(table
->data
, buffer
, len
))
1638 ((char *) table
->data
)[len
] = 0;
1641 len
= strlen(table
->data
);
1642 if (len
> table
->maxlen
)
1643 len
= table
->maxlen
;
1647 if(copy_to_user(buffer
, table
->data
, len
))
1650 if(put_user('\n', ((char __user
*) buffer
) + len
))
1661 * Special case of dostring for the UTS structure. This has locks
1662 * to observe. Should this be in kernel/sys.c ????
1665 static int proc_doutsstring(ctl_table
*table
, int write
, struct file
*filp
,
1666 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1671 down_read(&uts_sem
);
1672 r
=proc_dostring(table
,0,filp
,buffer
,lenp
, ppos
);
1675 down_write(&uts_sem
);
1676 r
=proc_dostring(table
,1,filp
,buffer
,lenp
, ppos
);
1682 static int do_proc_dointvec_conv(int *negp
, unsigned long *lvalp
,
1684 int write
, void *data
)
1687 *valp
= *negp
? -*lvalp
: *lvalp
;
1692 *lvalp
= (unsigned long)-val
;
1695 *lvalp
= (unsigned long)val
;
1701 static int do_proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1702 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
1703 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1704 int write
, void *data
),
1707 #define TMPBUFLEN 21
1708 int *i
, vleft
, first
=1, neg
, val
;
1712 char buf
[TMPBUFLEN
], *p
;
1713 char __user
*s
= buffer
;
1715 if (!table
->data
|| !table
->maxlen
|| !*lenp
||
1716 (*ppos
&& !write
)) {
1721 i
= (int *) table
->data
;
1722 vleft
= table
->maxlen
/ sizeof(*i
);
1726 conv
= do_proc_dointvec_conv
;
1728 for (; left
&& vleft
--; i
++, first
=0) {
1743 if (len
> sizeof(buf
) - 1)
1744 len
= sizeof(buf
) - 1;
1745 if (copy_from_user(buf
, s
, len
))
1749 if (*p
== '-' && left
> 1) {
1753 if (*p
< '0' || *p
> '9')
1756 lval
= simple_strtoul(p
, &p
, 0);
1759 if ((len
< left
) && *p
&& !isspace(*p
))
1766 if (conv(&neg
, &lval
, i
, 1, data
))
1773 if (conv(&neg
, &lval
, i
, 0, data
))
1776 sprintf(p
, "%s%lu", neg
? "-" : "", lval
);
1780 if(copy_to_user(s
, buf
, len
))
1787 if (!write
&& !first
&& left
) {
1788 if(put_user('\n', s
))
1795 if (get_user(c
, s
++))
1811 * proc_dointvec - read a vector of integers
1812 * @table: the sysctl table
1813 * @write: %TRUE if this is a write to the sysctl file
1814 * @filp: the file structure
1815 * @buffer: the user buffer
1816 * @lenp: the size of the user buffer
1817 * @ppos: file position
1819 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1820 * values from/to the user buffer, treated as an ASCII string.
1822 * Returns 0 on success.
1824 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1825 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1827 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;
1848 case OP_MAX
: if(*valp
< val
)
1851 case OP_MIN
: if(*valp
> val
)
1859 *lvalp
= (unsigned long)-val
;
1862 *lvalp
= (unsigned long)val
;
1869 * init may raise the set.
1872 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
1873 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1877 if (!capable(CAP_SYS_MODULE
)) {
1881 op
= (current
->pid
== 1) ? OP_SET
: OP_AND
;
1882 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1883 do_proc_dointvec_bset_conv
,&op
);
1886 struct do_proc_dointvec_minmax_conv_param
{
1891 static int do_proc_dointvec_minmax_conv(int *negp
, unsigned long *lvalp
,
1893 int write
, void *data
)
1895 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
1897 int val
= *negp
? -*lvalp
: *lvalp
;
1898 if ((param
->min
&& *param
->min
> val
) ||
1899 (param
->max
&& *param
->max
< val
))
1906 *lvalp
= (unsigned long)-val
;
1909 *lvalp
= (unsigned long)val
;
1916 * proc_dointvec_minmax - read a vector of integers with min/max values
1917 * @table: the sysctl table
1918 * @write: %TRUE if this is a write to the sysctl file
1919 * @filp: the file structure
1920 * @buffer: the user buffer
1921 * @lenp: the size of the user buffer
1922 * @ppos: file position
1924 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1925 * values from/to the user buffer, treated as an ASCII string.
1927 * This routine will ensure the values are within the range specified by
1928 * table->extra1 (min) and table->extra2 (max).
1930 * Returns 0 on success.
1932 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
1933 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1935 struct do_proc_dointvec_minmax_conv_param param
= {
1936 .min
= (int *) table
->extra1
,
1937 .max
= (int *) table
->extra2
,
1939 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
1940 do_proc_dointvec_minmax_conv
, ¶m
);
1943 static int do_proc_doulongvec_minmax(ctl_table
*table
, int write
,
1945 void __user
*buffer
,
1946 size_t *lenp
, loff_t
*ppos
,
1947 unsigned long convmul
,
1948 unsigned long convdiv
)
1950 #define TMPBUFLEN 21
1951 unsigned long *i
, *min
, *max
, val
;
1952 int vleft
, first
=1, neg
;
1954 char buf
[TMPBUFLEN
], *p
;
1955 char __user
*s
= buffer
;
1957 if (!table
->data
|| !table
->maxlen
|| !*lenp
||
1958 (*ppos
&& !write
)) {
1963 i
= (unsigned long *) table
->data
;
1964 min
= (unsigned long *) table
->extra1
;
1965 max
= (unsigned long *) table
->extra2
;
1966 vleft
= table
->maxlen
/ sizeof(unsigned long);
1969 for (; left
&& vleft
--; i
++, min
++, max
++, first
=0) {
1984 if (len
> TMPBUFLEN
-1)
1986 if (copy_from_user(buf
, s
, len
))
1990 if (*p
== '-' && left
> 1) {
1994 if (*p
< '0' || *p
> '9')
1996 val
= simple_strtoul(p
, &p
, 0) * convmul
/ convdiv
;
1998 if ((len
< left
) && *p
&& !isspace(*p
))
2007 if ((min
&& val
< *min
) || (max
&& val
> *max
))
2014 sprintf(p
, "%lu", convdiv
* (*i
) / convmul
);
2018 if(copy_to_user(s
, buf
, len
))
2025 if (!write
&& !first
&& left
) {
2026 if(put_user('\n', s
))
2033 if (get_user(c
, s
++))
2049 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2050 * @table: the sysctl table
2051 * @write: %TRUE if this is a write to the sysctl file
2052 * @filp: the file structure
2053 * @buffer: the user buffer
2054 * @lenp: the size of the user buffer
2055 * @ppos: file position
2057 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2058 * values from/to the user buffer, treated as an ASCII string.
2060 * This routine will ensure the values are within the range specified by
2061 * table->extra1 (min) and table->extra2 (max).
2063 * Returns 0 on success.
2065 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2066 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2068 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
, lenp
, ppos
, 1l, 1l);
2072 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2073 * @table: the sysctl table
2074 * @write: %TRUE if this is a write to the sysctl file
2075 * @filp: the file structure
2076 * @buffer: the user buffer
2077 * @lenp: the size of the user buffer
2078 * @ppos: file position
2080 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2081 * values from/to the user buffer, treated as an ASCII string. The values
2082 * are treated as milliseconds, and converted to jiffies when they are stored.
2084 * This routine will ensure the values are within the range specified by
2085 * table->extra1 (min) and table->extra2 (max).
2087 * Returns 0 on success.
2089 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2091 void __user
*buffer
,
2092 size_t *lenp
, loff_t
*ppos
)
2094 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
,
2095 lenp
, ppos
, HZ
, 1000l);
2099 static int do_proc_dointvec_jiffies_conv(int *negp
, unsigned long *lvalp
,
2101 int write
, void *data
)
2104 if (*lvalp
> LONG_MAX
/ HZ
)
2106 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2112 lval
= (unsigned long)-val
;
2115 lval
= (unsigned long)val
;
2122 static int do_proc_dointvec_userhz_jiffies_conv(int *negp
, unsigned long *lvalp
,
2124 int write
, void *data
)
2127 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2129 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2135 lval
= (unsigned long)-val
;
2138 lval
= (unsigned long)val
;
2140 *lvalp
= jiffies_to_clock_t(lval
);
2145 static int do_proc_dointvec_ms_jiffies_conv(int *negp
, unsigned long *lvalp
,
2147 int write
, void *data
)
2150 *valp
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2156 lval
= (unsigned long)-val
;
2159 lval
= (unsigned long)val
;
2161 *lvalp
= jiffies_to_msecs(lval
);
2167 * proc_dointvec_jiffies - read a vector of integers as seconds
2168 * @table: the sysctl table
2169 * @write: %TRUE if this is a write to the sysctl file
2170 * @filp: the file structure
2171 * @buffer: the user buffer
2172 * @lenp: the size of the user buffer
2173 * @ppos: file position
2175 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2176 * values from/to the user buffer, treated as an ASCII string.
2177 * The values read are assumed to be in seconds, and are converted into
2180 * Returns 0 on success.
2182 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2183 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2185 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2186 do_proc_dointvec_jiffies_conv
,NULL
);
2190 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2191 * @table: the sysctl table
2192 * @write: %TRUE if this is a write to the sysctl file
2193 * @filp: the file structure
2194 * @buffer: the user buffer
2195 * @lenp: the size of the user buffer
2196 * @ppos: pointer to the file position
2198 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2199 * values from/to the user buffer, treated as an ASCII string.
2200 * The values read are assumed to be in 1/USER_HZ seconds, and
2201 * are converted into jiffies.
2203 * Returns 0 on success.
2205 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2206 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2208 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2209 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2213 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2214 * @table: the sysctl table
2215 * @write: %TRUE if this is a write to the sysctl file
2216 * @filp: the file structure
2217 * @buffer: the user buffer
2218 * @lenp: the size of the user buffer
2219 * @ppos: file position
2220 * @ppos: the current position in the file
2222 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2223 * values from/to the user buffer, treated as an ASCII string.
2224 * The values read are assumed to be in 1/1000 seconds, and
2225 * are converted into jiffies.
2227 * Returns 0 on success.
2229 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2230 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2232 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2233 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2236 #else /* CONFIG_PROC_FS */
2238 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
2239 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2244 static int proc_doutsstring(ctl_table
*table
, int write
, struct file
*filp
,
2245 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2250 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
2251 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2256 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
2257 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2262 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2263 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2268 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2269 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2274 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2275 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2280 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2281 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2286 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2287 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2292 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2294 void __user
*buffer
,
2295 size_t *lenp
, loff_t
*ppos
)
2301 #endif /* CONFIG_PROC_FS */
2305 * General sysctl support routines
2308 /* The generic string strategy routine: */
2309 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2310 void __user
*oldval
, size_t __user
*oldlenp
,
2311 void __user
*newval
, size_t newlen
, void **context
)
2313 if (!table
->data
|| !table
->maxlen
)
2316 if (oldval
&& oldlenp
) {
2318 if (get_user(bufsize
, oldlenp
))
2321 size_t len
= strlen(table
->data
), copied
;
2323 /* This shouldn't trigger for a well-formed sysctl */
2324 if (len
> table
->maxlen
)
2325 len
= table
->maxlen
;
2327 /* Copy up to a max of bufsize-1 bytes of the string */
2328 copied
= (len
>= bufsize
) ? bufsize
- 1 : len
;
2330 if (copy_to_user(oldval
, table
->data
, copied
) ||
2331 put_user(0, (char __user
*)(oldval
+ copied
)))
2333 if (put_user(len
, oldlenp
))
2337 if (newval
&& newlen
) {
2338 size_t len
= newlen
;
2339 if (len
> table
->maxlen
)
2340 len
= table
->maxlen
;
2341 if(copy_from_user(table
->data
, newval
, len
))
2343 if (len
== table
->maxlen
)
2345 ((char *) table
->data
)[len
] = 0;
2351 * This function makes sure that all of the integers in the vector
2352 * are between the minimum and maximum values given in the arrays
2353 * table->extra1 and table->extra2, respectively.
2355 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2356 void __user
*oldval
, size_t __user
*oldlenp
,
2357 void __user
*newval
, size_t newlen
, void **context
)
2360 if (newval
&& newlen
) {
2361 int __user
*vec
= (int __user
*) newval
;
2362 int *min
= (int *) table
->extra1
;
2363 int *max
= (int *) table
->extra2
;
2367 if (newlen
% sizeof(int) != 0)
2370 if (!table
->extra1
&& !table
->extra2
)
2373 if (newlen
> table
->maxlen
)
2374 newlen
= table
->maxlen
;
2375 length
= newlen
/ sizeof(int);
2377 for (i
= 0; i
< length
; i
++) {
2379 if (get_user(value
, vec
+ i
))
2381 if (min
&& value
< min
[i
])
2383 if (max
&& value
> max
[i
])
2390 /* Strategy function to convert jiffies to seconds */
2391 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2392 void __user
*oldval
, size_t __user
*oldlenp
,
2393 void __user
*newval
, size_t newlen
, void **context
)
2398 if (get_user(olen
, oldlenp
))
2400 if (olen
!=sizeof(int))
2403 if (put_user(*(int *)(table
->data
)/HZ
, (int __user
*)oldval
) ||
2404 (oldlenp
&& put_user(sizeof(int),oldlenp
)))
2407 if (newval
&& newlen
) {
2409 if (newlen
!= sizeof(int))
2411 if (get_user(new, (int __user
*)newval
))
2413 *(int *)(table
->data
) = new*HZ
;
2418 /* Strategy function to convert jiffies to seconds */
2419 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2420 void __user
*oldval
, size_t __user
*oldlenp
,
2421 void __user
*newval
, size_t newlen
, void **context
)
2426 if (get_user(olen
, oldlenp
))
2428 if (olen
!=sizeof(int))
2431 if (put_user(jiffies_to_msecs(*(int *)(table
->data
)), (int __user
*)oldval
) ||
2432 (oldlenp
&& put_user(sizeof(int),oldlenp
)))
2435 if (newval
&& newlen
) {
2437 if (newlen
!= sizeof(int))
2439 if (get_user(new, (int __user
*)newval
))
2441 *(int *)(table
->data
) = msecs_to_jiffies(new);
2446 #else /* CONFIG_SYSCTL */
2449 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
2454 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2455 void __user
*oldval
, size_t __user
*oldlenp
,
2456 void __user
*newval
, size_t newlen
, void **context
)
2461 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2462 void __user
*oldval
, size_t __user
*oldlenp
,
2463 void __user
*newval
, size_t newlen
, void **context
)
2468 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2469 void __user
*oldval
, size_t __user
*oldlenp
,
2470 void __user
*newval
, size_t newlen
, void **context
)
2475 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2476 void __user
*oldval
, size_t __user
*oldlenp
,
2477 void __user
*newval
, size_t newlen
, void **context
)
2482 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
2483 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2488 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
2489 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2494 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
2495 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2500 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2501 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2506 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2507 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2512 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2513 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2518 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2519 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2524 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2525 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2530 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2532 void __user
*buffer
,
2533 size_t *lenp
, loff_t
*ppos
)
2538 struct ctl_table_header
* register_sysctl_table(ctl_table
* table
,
2544 void unregister_sysctl_table(struct ctl_table_header
* table
)
2548 #endif /* CONFIG_SYSCTL */
2551 * No sense putting this after each symbol definition, twice,
2552 * exception granted :-)
2554 EXPORT_SYMBOL(proc_dointvec
);
2555 EXPORT_SYMBOL(proc_dointvec_jiffies
);
2556 EXPORT_SYMBOL(proc_dointvec_minmax
);
2557 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
2558 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
2559 EXPORT_SYMBOL(proc_dostring
);
2560 EXPORT_SYMBOL(proc_doulongvec_minmax
);
2561 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);
2562 EXPORT_SYMBOL(register_sysctl_table
);
2563 EXPORT_SYMBOL(sysctl_intvec
);
2564 EXPORT_SYMBOL(sysctl_jiffies
);
2565 EXPORT_SYMBOL(sysctl_ms_jiffies
);
2566 EXPORT_SYMBOL(sysctl_string
);
2567 EXPORT_SYMBOL(unregister_sysctl_table
);