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/config.h>
22 #include <linux/module.h>
24 #include <linux/swap.h>
25 #include <linux/slab.h>
26 #include <linux/sysctl.h>
27 #include <linux/proc_fs.h>
28 #include <linux/capability.h>
29 #include <linux/ctype.h>
30 #include <linux/utsname.h>
31 #include <linux/capability.h>
32 #include <linux/smp_lock.h>
33 #include <linux/init.h>
34 #include <linux/kernel.h>
35 #include <linux/kobject.h>
36 #include <linux/net.h>
37 #include <linux/sysrq.h>
38 #include <linux/highuid.h>
39 #include <linux/writeback.h>
40 #include <linux/hugetlb.h>
41 #include <linux/security.h>
42 #include <linux/initrd.h>
43 #include <linux/times.h>
44 #include <linux/limits.h>
45 #include <linux/dcache.h>
46 #include <linux/syscalls.h>
47 #include <linux/nfs_fs.h>
48 #include <linux/acpi.h>
50 #include <asm/uaccess.h>
51 #include <asm/processor.h>
53 #if defined(CONFIG_SYSCTL)
55 /* External variables not in a header file. */
57 extern int sysctl_overcommit_memory
;
58 extern int sysctl_overcommit_ratio
;
59 extern int max_threads
;
60 extern int sysrq_enabled
;
61 extern int core_uses_pid
;
62 extern int suid_dumpable
;
63 extern char core_pattern
[];
66 extern int min_free_kbytes
;
67 extern int printk_ratelimit_jiffies
;
68 extern int printk_ratelimit_burst
;
69 extern int pid_max_min
, pid_max_max
;
70 extern int sysctl_drop_caches
;
71 extern int percpu_pagelist_fraction
;
73 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
74 int unknown_nmi_panic
;
75 extern int proc_unknown_nmi_panic(ctl_table
*, int, struct file
*,
76 void __user
*, size_t *, loff_t
*);
79 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
80 static int maxolduid
= 65535;
82 static int min_percpu_pagelist_fract
= 8;
84 static int ngroups_max
= NGROUPS_MAX
;
87 extern char modprobe_path
[];
89 #ifdef CONFIG_CHR_DEV_SG
90 extern int sg_big_buff
;
93 extern size_t shm_ctlmax
;
94 extern size_t shm_ctlall
;
95 extern int shm_ctlmni
;
96 extern int msg_ctlmax
;
97 extern int msg_ctlmnb
;
98 extern int msg_ctlmni
;
99 extern int sem_ctls
[];
103 extern char reboot_command
[];
104 extern int stop_a_enabled
;
105 extern int scons_pwroff
;
109 extern int pwrsw_enabled
;
110 extern int unaligned_enabled
;
114 #ifdef CONFIG_MATHEMU
115 extern int sysctl_ieee_emulation_warnings
;
117 extern int sysctl_userprocess_debug
;
118 extern int spin_retry
;
121 extern int sysctl_hz_timer
;
123 #ifdef CONFIG_BSD_PROCESS_ACCT
124 extern int acct_parm
[];
127 static int parse_table(int __user
*, int, void __user
*, size_t __user
*, void __user
*, size_t,
128 ctl_table
*, void **);
129 static int proc_doutsstring(ctl_table
*table
, int write
, struct file
*filp
,
130 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
132 static ctl_table root_table
[];
133 static struct ctl_table_header root_table_header
=
134 { root_table
, LIST_HEAD_INIT(root_table_header
.ctl_entry
) };
136 static ctl_table kern_table
[];
137 static ctl_table vm_table
[];
138 static ctl_table proc_table
[];
139 static ctl_table fs_table
[];
140 static ctl_table debug_table
[];
141 static ctl_table dev_table
[];
142 extern ctl_table random_table
[];
143 #ifdef CONFIG_UNIX98_PTYS
144 extern ctl_table pty_table
[];
146 #ifdef CONFIG_INOTIFY
147 extern ctl_table inotify_table
[];
150 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
151 int sysctl_legacy_va_layout
;
154 /* /proc declarations: */
156 #ifdef CONFIG_PROC_FS
158 static ssize_t
proc_readsys(struct file
*, char __user
*, size_t, loff_t
*);
159 static ssize_t
proc_writesys(struct file
*, const char __user
*, size_t, loff_t
*);
160 static int proc_opensys(struct inode
*, struct file
*);
162 struct file_operations proc_sys_file_operations
= {
163 .open
= proc_opensys
,
164 .read
= proc_readsys
,
165 .write
= proc_writesys
,
168 extern struct proc_dir_entry
*proc_sys_root
;
170 static void register_proc_table(ctl_table
*, struct proc_dir_entry
*, void *);
171 static void unregister_proc_table(ctl_table
*, struct proc_dir_entry
*);
174 /* The default sysctl tables: */
176 static ctl_table root_table
[] = {
178 .ctl_name
= CTL_KERN
,
179 .procname
= "kernel",
198 .ctl_name
= CTL_PROC
,
210 .ctl_name
= CTL_DEBUG
,
213 .child
= debug_table
,
225 static ctl_table kern_table
[] = {
227 .ctl_name
= KERN_OSTYPE
,
228 .procname
= "ostype",
229 .data
= system_utsname
.sysname
,
230 .maxlen
= sizeof(system_utsname
.sysname
),
232 .proc_handler
= &proc_doutsstring
,
233 .strategy
= &sysctl_string
,
236 .ctl_name
= KERN_OSRELEASE
,
237 .procname
= "osrelease",
238 .data
= system_utsname
.release
,
239 .maxlen
= sizeof(system_utsname
.release
),
241 .proc_handler
= &proc_doutsstring
,
242 .strategy
= &sysctl_string
,
245 .ctl_name
= KERN_VERSION
,
246 .procname
= "version",
247 .data
= system_utsname
.version
,
248 .maxlen
= sizeof(system_utsname
.version
),
250 .proc_handler
= &proc_doutsstring
,
251 .strategy
= &sysctl_string
,
254 .ctl_name
= KERN_NODENAME
,
255 .procname
= "hostname",
256 .data
= system_utsname
.nodename
,
257 .maxlen
= sizeof(system_utsname
.nodename
),
259 .proc_handler
= &proc_doutsstring
,
260 .strategy
= &sysctl_string
,
263 .ctl_name
= KERN_DOMAINNAME
,
264 .procname
= "domainname",
265 .data
= system_utsname
.domainname
,
266 .maxlen
= sizeof(system_utsname
.domainname
),
268 .proc_handler
= &proc_doutsstring
,
269 .strategy
= &sysctl_string
,
272 .ctl_name
= KERN_PANIC
,
274 .data
= &panic_timeout
,
275 .maxlen
= sizeof(int),
277 .proc_handler
= &proc_dointvec
,
280 .ctl_name
= KERN_CORE_USES_PID
,
281 .procname
= "core_uses_pid",
282 .data
= &core_uses_pid
,
283 .maxlen
= sizeof(int),
285 .proc_handler
= &proc_dointvec
,
288 .ctl_name
= KERN_CORE_PATTERN
,
289 .procname
= "core_pattern",
290 .data
= core_pattern
,
293 .proc_handler
= &proc_dostring
,
294 .strategy
= &sysctl_string
,
297 .ctl_name
= KERN_TAINTED
,
298 .procname
= "tainted",
300 .maxlen
= sizeof(int),
302 .proc_handler
= &proc_dointvec
,
305 .ctl_name
= KERN_CAP_BSET
,
306 .procname
= "cap-bound",
308 .maxlen
= sizeof(kernel_cap_t
),
310 .proc_handler
= &proc_dointvec_bset
,
312 #ifdef CONFIG_BLK_DEV_INITRD
314 .ctl_name
= KERN_REALROOTDEV
,
315 .procname
= "real-root-dev",
316 .data
= &real_root_dev
,
317 .maxlen
= sizeof(int),
319 .proc_handler
= &proc_dointvec
,
324 .ctl_name
= KERN_SPARC_REBOOT
,
325 .procname
= "reboot-cmd",
326 .data
= reboot_command
,
329 .proc_handler
= &proc_dostring
,
330 .strategy
= &sysctl_string
,
333 .ctl_name
= KERN_SPARC_STOP_A
,
334 .procname
= "stop-a",
335 .data
= &stop_a_enabled
,
336 .maxlen
= sizeof (int),
338 .proc_handler
= &proc_dointvec
,
341 .ctl_name
= KERN_SPARC_SCONS_PWROFF
,
342 .procname
= "scons-poweroff",
343 .data
= &scons_pwroff
,
344 .maxlen
= sizeof (int),
346 .proc_handler
= &proc_dointvec
,
351 .ctl_name
= KERN_HPPA_PWRSW
,
352 .procname
= "soft-power",
353 .data
= &pwrsw_enabled
,
354 .maxlen
= sizeof (int),
356 .proc_handler
= &proc_dointvec
,
359 .ctl_name
= KERN_HPPA_UNALIGNED
,
360 .procname
= "unaligned-trap",
361 .data
= &unaligned_enabled
,
362 .maxlen
= sizeof (int),
364 .proc_handler
= &proc_dointvec
,
368 .ctl_name
= KERN_CTLALTDEL
,
369 .procname
= "ctrl-alt-del",
371 .maxlen
= sizeof(int),
373 .proc_handler
= &proc_dointvec
,
376 .ctl_name
= KERN_PRINTK
,
377 .procname
= "printk",
378 .data
= &console_loglevel
,
379 .maxlen
= 4*sizeof(int),
381 .proc_handler
= &proc_dointvec
,
385 .ctl_name
= KERN_MODPROBE
,
386 .procname
= "modprobe",
387 .data
= &modprobe_path
,
388 .maxlen
= KMOD_PATH_LEN
,
390 .proc_handler
= &proc_dostring
,
391 .strategy
= &sysctl_string
,
394 #ifdef CONFIG_HOTPLUG
396 .ctl_name
= KERN_HOTPLUG
,
397 .procname
= "hotplug",
398 .data
= &uevent_helper
,
399 .maxlen
= UEVENT_HELPER_PATH_LEN
,
401 .proc_handler
= &proc_dostring
,
402 .strategy
= &sysctl_string
,
405 #ifdef CONFIG_CHR_DEV_SG
407 .ctl_name
= KERN_SG_BIG_BUFF
,
408 .procname
= "sg-big-buff",
409 .data
= &sg_big_buff
,
410 .maxlen
= sizeof (int),
412 .proc_handler
= &proc_dointvec
,
415 #ifdef CONFIG_BSD_PROCESS_ACCT
417 .ctl_name
= KERN_ACCT
,
420 .maxlen
= 3*sizeof(int),
422 .proc_handler
= &proc_dointvec
,
425 #ifdef CONFIG_SYSVIPC
427 .ctl_name
= KERN_SHMMAX
,
428 .procname
= "shmmax",
430 .maxlen
= sizeof (size_t),
432 .proc_handler
= &proc_doulongvec_minmax
,
435 .ctl_name
= KERN_SHMALL
,
436 .procname
= "shmall",
438 .maxlen
= sizeof (size_t),
440 .proc_handler
= &proc_doulongvec_minmax
,
443 .ctl_name
= KERN_SHMMNI
,
444 .procname
= "shmmni",
446 .maxlen
= sizeof (int),
448 .proc_handler
= &proc_dointvec
,
451 .ctl_name
= KERN_MSGMAX
,
452 .procname
= "msgmax",
454 .maxlen
= sizeof (int),
456 .proc_handler
= &proc_dointvec
,
459 .ctl_name
= KERN_MSGMNI
,
460 .procname
= "msgmni",
462 .maxlen
= sizeof (int),
464 .proc_handler
= &proc_dointvec
,
467 .ctl_name
= KERN_MSGMNB
,
468 .procname
= "msgmnb",
470 .maxlen
= sizeof (int),
472 .proc_handler
= &proc_dointvec
,
475 .ctl_name
= KERN_SEM
,
478 .maxlen
= 4*sizeof (int),
480 .proc_handler
= &proc_dointvec
,
483 #ifdef CONFIG_MAGIC_SYSRQ
485 .ctl_name
= KERN_SYSRQ
,
487 .data
= &sysrq_enabled
,
488 .maxlen
= sizeof (int),
490 .proc_handler
= &proc_dointvec
,
494 .ctl_name
= KERN_CADPID
,
495 .procname
= "cad_pid",
497 .maxlen
= sizeof (int),
499 .proc_handler
= &proc_dointvec
,
502 .ctl_name
= KERN_MAX_THREADS
,
503 .procname
= "threads-max",
504 .data
= &max_threads
,
505 .maxlen
= sizeof(int),
507 .proc_handler
= &proc_dointvec
,
510 .ctl_name
= KERN_RANDOM
,
511 .procname
= "random",
513 .child
= random_table
,
515 #ifdef CONFIG_UNIX98_PTYS
517 .ctl_name
= KERN_PTY
,
524 .ctl_name
= KERN_OVERFLOWUID
,
525 .procname
= "overflowuid",
526 .data
= &overflowuid
,
527 .maxlen
= sizeof(int),
529 .proc_handler
= &proc_dointvec_minmax
,
530 .strategy
= &sysctl_intvec
,
531 .extra1
= &minolduid
,
532 .extra2
= &maxolduid
,
535 .ctl_name
= KERN_OVERFLOWGID
,
536 .procname
= "overflowgid",
537 .data
= &overflowgid
,
538 .maxlen
= sizeof(int),
540 .proc_handler
= &proc_dointvec_minmax
,
541 .strategy
= &sysctl_intvec
,
542 .extra1
= &minolduid
,
543 .extra2
= &maxolduid
,
546 #ifdef CONFIG_MATHEMU
548 .ctl_name
= KERN_IEEE_EMULATION_WARNINGS
,
549 .procname
= "ieee_emulation_warnings",
550 .data
= &sysctl_ieee_emulation_warnings
,
551 .maxlen
= sizeof(int),
553 .proc_handler
= &proc_dointvec
,
556 #ifdef CONFIG_NO_IDLE_HZ
558 .ctl_name
= KERN_HZ_TIMER
,
559 .procname
= "hz_timer",
560 .data
= &sysctl_hz_timer
,
561 .maxlen
= sizeof(int),
563 .proc_handler
= &proc_dointvec
,
567 .ctl_name
= KERN_S390_USER_DEBUG_LOGGING
,
568 .procname
= "userprocess_debug",
569 .data
= &sysctl_userprocess_debug
,
570 .maxlen
= sizeof(int),
572 .proc_handler
= &proc_dointvec
,
576 .ctl_name
= KERN_PIDMAX
,
577 .procname
= "pid_max",
579 .maxlen
= sizeof (int),
581 .proc_handler
= &proc_dointvec_minmax
,
582 .strategy
= sysctl_intvec
,
583 .extra1
= &pid_max_min
,
584 .extra2
= &pid_max_max
,
587 .ctl_name
= KERN_PANIC_ON_OOPS
,
588 .procname
= "panic_on_oops",
589 .data
= &panic_on_oops
,
590 .maxlen
= sizeof(int),
592 .proc_handler
= &proc_dointvec
,
595 .ctl_name
= KERN_PRINTK_RATELIMIT
,
596 .procname
= "printk_ratelimit",
597 .data
= &printk_ratelimit_jiffies
,
598 .maxlen
= sizeof(int),
600 .proc_handler
= &proc_dointvec_jiffies
,
601 .strategy
= &sysctl_jiffies
,
604 .ctl_name
= KERN_PRINTK_RATELIMIT_BURST
,
605 .procname
= "printk_ratelimit_burst",
606 .data
= &printk_ratelimit_burst
,
607 .maxlen
= sizeof(int),
609 .proc_handler
= &proc_dointvec
,
612 .ctl_name
= KERN_NGROUPS_MAX
,
613 .procname
= "ngroups_max",
614 .data
= &ngroups_max
,
615 .maxlen
= sizeof (int),
617 .proc_handler
= &proc_dointvec
,
619 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
621 .ctl_name
= KERN_UNKNOWN_NMI_PANIC
,
622 .procname
= "unknown_nmi_panic",
623 .data
= &unknown_nmi_panic
,
624 .maxlen
= sizeof (int),
626 .proc_handler
= &proc_unknown_nmi_panic
,
629 #if defined(CONFIG_X86)
631 .ctl_name
= KERN_BOOTLOADER_TYPE
,
632 .procname
= "bootloader_type",
633 .data
= &bootloader_type
,
634 .maxlen
= sizeof (int),
636 .proc_handler
= &proc_dointvec
,
639 #if defined(CONFIG_MMU)
641 .ctl_name
= KERN_RANDOMIZE
,
642 .procname
= "randomize_va_space",
643 .data
= &randomize_va_space
,
644 .maxlen
= sizeof(int),
646 .proc_handler
= &proc_dointvec
,
649 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
651 .ctl_name
= KERN_SPIN_RETRY
,
652 .procname
= "spin_retry",
654 .maxlen
= sizeof (int),
656 .proc_handler
= &proc_dointvec
,
659 #ifdef CONFIG_ACPI_SLEEP
661 .ctl_name
= KERN_ACPI_VIDEO_FLAGS
,
662 .procname
= "acpi_video_flags",
663 .data
= &acpi_video_flags
,
664 .maxlen
= sizeof (unsigned long),
666 .proc_handler
= &proc_dointvec
,
672 /* Constants for minimum and maximum testing in vm_table.
673 We use these as one-element integer vectors. */
675 static int one_hundred
= 100;
678 static ctl_table vm_table
[] = {
680 .ctl_name
= VM_OVERCOMMIT_MEMORY
,
681 .procname
= "overcommit_memory",
682 .data
= &sysctl_overcommit_memory
,
683 .maxlen
= sizeof(sysctl_overcommit_memory
),
685 .proc_handler
= &proc_dointvec
,
688 .ctl_name
= VM_OVERCOMMIT_RATIO
,
689 .procname
= "overcommit_ratio",
690 .data
= &sysctl_overcommit_ratio
,
691 .maxlen
= sizeof(sysctl_overcommit_ratio
),
693 .proc_handler
= &proc_dointvec
,
696 .ctl_name
= VM_PAGE_CLUSTER
,
697 .procname
= "page-cluster",
698 .data
= &page_cluster
,
699 .maxlen
= sizeof(int),
701 .proc_handler
= &proc_dointvec
,
704 .ctl_name
= VM_DIRTY_BACKGROUND
,
705 .procname
= "dirty_background_ratio",
706 .data
= &dirty_background_ratio
,
707 .maxlen
= sizeof(dirty_background_ratio
),
709 .proc_handler
= &proc_dointvec_minmax
,
710 .strategy
= &sysctl_intvec
,
712 .extra2
= &one_hundred
,
715 .ctl_name
= VM_DIRTY_RATIO
,
716 .procname
= "dirty_ratio",
717 .data
= &vm_dirty_ratio
,
718 .maxlen
= sizeof(vm_dirty_ratio
),
720 .proc_handler
= &proc_dointvec_minmax
,
721 .strategy
= &sysctl_intvec
,
723 .extra2
= &one_hundred
,
726 .ctl_name
= VM_DIRTY_WB_CS
,
727 .procname
= "dirty_writeback_centisecs",
728 .data
= &dirty_writeback_centisecs
,
729 .maxlen
= sizeof(dirty_writeback_centisecs
),
731 .proc_handler
= &dirty_writeback_centisecs_handler
,
734 .ctl_name
= VM_DIRTY_EXPIRE_CS
,
735 .procname
= "dirty_expire_centisecs",
736 .data
= &dirty_expire_centisecs
,
737 .maxlen
= sizeof(dirty_expire_centisecs
),
739 .proc_handler
= &proc_dointvec
,
742 .ctl_name
= VM_NR_PDFLUSH_THREADS
,
743 .procname
= "nr_pdflush_threads",
744 .data
= &nr_pdflush_threads
,
745 .maxlen
= sizeof nr_pdflush_threads
,
746 .mode
= 0444 /* read-only*/,
747 .proc_handler
= &proc_dointvec
,
750 .ctl_name
= VM_SWAPPINESS
,
751 .procname
= "swappiness",
752 .data
= &vm_swappiness
,
753 .maxlen
= sizeof(vm_swappiness
),
755 .proc_handler
= &proc_dointvec_minmax
,
756 .strategy
= &sysctl_intvec
,
758 .extra2
= &one_hundred
,
760 #ifdef CONFIG_HUGETLB_PAGE
762 .ctl_name
= VM_HUGETLB_PAGES
,
763 .procname
= "nr_hugepages",
764 .data
= &max_huge_pages
,
765 .maxlen
= sizeof(unsigned long),
767 .proc_handler
= &hugetlb_sysctl_handler
,
768 .extra1
= (void *)&hugetlb_zero
,
769 .extra2
= (void *)&hugetlb_infinity
,
772 .ctl_name
= VM_HUGETLB_GROUP
,
773 .procname
= "hugetlb_shm_group",
774 .data
= &sysctl_hugetlb_shm_group
,
775 .maxlen
= sizeof(gid_t
),
777 .proc_handler
= &proc_dointvec
,
781 .ctl_name
= VM_LOWMEM_RESERVE_RATIO
,
782 .procname
= "lowmem_reserve_ratio",
783 .data
= &sysctl_lowmem_reserve_ratio
,
784 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
786 .proc_handler
= &lowmem_reserve_ratio_sysctl_handler
,
787 .strategy
= &sysctl_intvec
,
790 .ctl_name
= VM_DROP_PAGECACHE
,
791 .procname
= "drop_caches",
792 .data
= &sysctl_drop_caches
,
793 .maxlen
= sizeof(int),
795 .proc_handler
= drop_caches_sysctl_handler
,
796 .strategy
= &sysctl_intvec
,
799 .ctl_name
= VM_MIN_FREE_KBYTES
,
800 .procname
= "min_free_kbytes",
801 .data
= &min_free_kbytes
,
802 .maxlen
= sizeof(min_free_kbytes
),
804 .proc_handler
= &min_free_kbytes_sysctl_handler
,
805 .strategy
= &sysctl_intvec
,
809 .ctl_name
= VM_PERCPU_PAGELIST_FRACTION
,
810 .procname
= "percpu_pagelist_fraction",
811 .data
= &percpu_pagelist_fraction
,
812 .maxlen
= sizeof(percpu_pagelist_fraction
),
814 .proc_handler
= &percpu_pagelist_fraction_sysctl_handler
,
815 .strategy
= &sysctl_intvec
,
816 .extra1
= &min_percpu_pagelist_fract
,
820 .ctl_name
= VM_MAX_MAP_COUNT
,
821 .procname
= "max_map_count",
822 .data
= &sysctl_max_map_count
,
823 .maxlen
= sizeof(sysctl_max_map_count
),
825 .proc_handler
= &proc_dointvec
829 .ctl_name
= VM_LAPTOP_MODE
,
830 .procname
= "laptop_mode",
831 .data
= &laptop_mode
,
832 .maxlen
= sizeof(laptop_mode
),
834 .proc_handler
= &proc_dointvec
,
835 .strategy
= &sysctl_intvec
,
839 .ctl_name
= VM_BLOCK_DUMP
,
840 .procname
= "block_dump",
842 .maxlen
= sizeof(block_dump
),
844 .proc_handler
= &proc_dointvec
,
845 .strategy
= &sysctl_intvec
,
849 .ctl_name
= VM_VFS_CACHE_PRESSURE
,
850 .procname
= "vfs_cache_pressure",
851 .data
= &sysctl_vfs_cache_pressure
,
852 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
854 .proc_handler
= &proc_dointvec
,
855 .strategy
= &sysctl_intvec
,
858 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
860 .ctl_name
= VM_LEGACY_VA_LAYOUT
,
861 .procname
= "legacy_va_layout",
862 .data
= &sysctl_legacy_va_layout
,
863 .maxlen
= sizeof(sysctl_legacy_va_layout
),
865 .proc_handler
= &proc_dointvec
,
866 .strategy
= &sysctl_intvec
,
872 .ctl_name
= VM_SWAP_TOKEN_TIMEOUT
,
873 .procname
= "swap_token_timeout",
874 .data
= &swap_token_default_timeout
,
875 .maxlen
= sizeof(swap_token_default_timeout
),
877 .proc_handler
= &proc_dointvec_jiffies
,
878 .strategy
= &sysctl_jiffies
,
883 .ctl_name
= VM_ZONE_RECLAIM_MODE
,
884 .procname
= "zone_reclaim_mode",
885 .data
= &zone_reclaim_mode
,
886 .maxlen
= sizeof(zone_reclaim_mode
),
888 .proc_handler
= &proc_dointvec
,
889 .strategy
= &sysctl_intvec
,
893 .ctl_name
= VM_ZONE_RECLAIM_INTERVAL
,
894 .procname
= "zone_reclaim_interval",
895 .data
= &zone_reclaim_interval
,
896 .maxlen
= sizeof(zone_reclaim_interval
),
898 .proc_handler
= &proc_dointvec_jiffies
,
899 .strategy
= &sysctl_jiffies
,
905 static ctl_table proc_table
[] = {
909 static ctl_table fs_table
[] = {
911 .ctl_name
= FS_NRINODE
,
912 .procname
= "inode-nr",
913 .data
= &inodes_stat
,
914 .maxlen
= 2*sizeof(int),
916 .proc_handler
= &proc_dointvec
,
919 .ctl_name
= FS_STATINODE
,
920 .procname
= "inode-state",
921 .data
= &inodes_stat
,
922 .maxlen
= 7*sizeof(int),
924 .proc_handler
= &proc_dointvec
,
927 .ctl_name
= FS_NRFILE
,
928 .procname
= "file-nr",
930 .maxlen
= 3*sizeof(int),
932 .proc_handler
= &proc_dointvec
,
935 .ctl_name
= FS_MAXFILE
,
936 .procname
= "file-max",
937 .data
= &files_stat
.max_files
,
938 .maxlen
= sizeof(int),
940 .proc_handler
= &proc_dointvec
,
943 .ctl_name
= FS_DENTRY
,
944 .procname
= "dentry-state",
945 .data
= &dentry_stat
,
946 .maxlen
= 6*sizeof(int),
948 .proc_handler
= &proc_dointvec
,
951 .ctl_name
= FS_OVERFLOWUID
,
952 .procname
= "overflowuid",
953 .data
= &fs_overflowuid
,
954 .maxlen
= sizeof(int),
956 .proc_handler
= &proc_dointvec_minmax
,
957 .strategy
= &sysctl_intvec
,
958 .extra1
= &minolduid
,
959 .extra2
= &maxolduid
,
962 .ctl_name
= FS_OVERFLOWGID
,
963 .procname
= "overflowgid",
964 .data
= &fs_overflowgid
,
965 .maxlen
= sizeof(int),
967 .proc_handler
= &proc_dointvec_minmax
,
968 .strategy
= &sysctl_intvec
,
969 .extra1
= &minolduid
,
970 .extra2
= &maxolduid
,
973 .ctl_name
= FS_LEASES
,
974 .procname
= "leases-enable",
975 .data
= &leases_enable
,
976 .maxlen
= sizeof(int),
978 .proc_handler
= &proc_dointvec
,
980 #ifdef CONFIG_DNOTIFY
982 .ctl_name
= FS_DIR_NOTIFY
,
983 .procname
= "dir-notify-enable",
984 .data
= &dir_notify_enable
,
985 .maxlen
= sizeof(int),
987 .proc_handler
= &proc_dointvec
,
992 .ctl_name
= FS_LEASE_TIME
,
993 .procname
= "lease-break-time",
994 .data
= &lease_break_time
,
995 .maxlen
= sizeof(int),
997 .proc_handler
= &proc_dointvec
,
1000 .ctl_name
= FS_AIO_NR
,
1001 .procname
= "aio-nr",
1003 .maxlen
= sizeof(aio_nr
),
1005 .proc_handler
= &proc_doulongvec_minmax
,
1008 .ctl_name
= FS_AIO_MAX_NR
,
1009 .procname
= "aio-max-nr",
1010 .data
= &aio_max_nr
,
1011 .maxlen
= sizeof(aio_max_nr
),
1013 .proc_handler
= &proc_doulongvec_minmax
,
1015 #ifdef CONFIG_INOTIFY
1017 .ctl_name
= FS_INOTIFY
,
1018 .procname
= "inotify",
1020 .child
= inotify_table
,
1025 .ctl_name
= KERN_SETUID_DUMPABLE
,
1026 .procname
= "suid_dumpable",
1027 .data
= &suid_dumpable
,
1028 .maxlen
= sizeof(int),
1030 .proc_handler
= &proc_dointvec
,
1035 static ctl_table debug_table
[] = {
1039 static ctl_table dev_table
[] = {
1043 extern void init_irq_proc (void);
1045 static DEFINE_SPINLOCK(sysctl_lock
);
1047 /* called under sysctl_lock */
1048 static int use_table(struct ctl_table_header
*p
)
1050 if (unlikely(p
->unregistering
))
1056 /* called under sysctl_lock */
1057 static void unuse_table(struct ctl_table_header
*p
)
1060 if (unlikely(p
->unregistering
))
1061 complete(p
->unregistering
);
1064 /* called under sysctl_lock, will reacquire if has to wait */
1065 static void start_unregistering(struct ctl_table_header
*p
)
1068 * if p->used is 0, nobody will ever touch that entry again;
1069 * we'll eliminate all paths to it before dropping sysctl_lock
1071 if (unlikely(p
->used
)) {
1072 struct completion wait
;
1073 init_completion(&wait
);
1074 p
->unregistering
= &wait
;
1075 spin_unlock(&sysctl_lock
);
1076 wait_for_completion(&wait
);
1077 spin_lock(&sysctl_lock
);
1080 * do not remove from the list until nobody holds it; walking the
1081 * list in do_sysctl() relies on that.
1083 list_del_init(&p
->ctl_entry
);
1086 void __init
sysctl_init(void)
1088 #ifdef CONFIG_PROC_FS
1089 register_proc_table(root_table
, proc_sys_root
, &root_table_header
);
1094 int do_sysctl(int __user
*name
, int nlen
, void __user
*oldval
, size_t __user
*oldlenp
,
1095 void __user
*newval
, size_t newlen
)
1097 struct list_head
*tmp
;
1098 int error
= -ENOTDIR
;
1100 if (nlen
<= 0 || nlen
>= CTL_MAXNAME
)
1104 if (!oldlenp
|| get_user(old_len
, oldlenp
))
1107 spin_lock(&sysctl_lock
);
1108 tmp
= &root_table_header
.ctl_entry
;
1110 struct ctl_table_header
*head
=
1111 list_entry(tmp
, struct ctl_table_header
, ctl_entry
);
1112 void *context
= NULL
;
1114 if (!use_table(head
))
1117 spin_unlock(&sysctl_lock
);
1119 error
= parse_table(name
, nlen
, oldval
, oldlenp
,
1120 newval
, newlen
, head
->ctl_table
,
1124 spin_lock(&sysctl_lock
);
1126 if (error
!= -ENOTDIR
)
1128 } while ((tmp
= tmp
->next
) != &root_table_header
.ctl_entry
);
1129 spin_unlock(&sysctl_lock
);
1133 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
1135 struct __sysctl_args tmp
;
1138 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
1142 error
= do_sysctl(tmp
.name
, tmp
.nlen
, tmp
.oldval
, tmp
.oldlenp
,
1143 tmp
.newval
, tmp
.newlen
);
1149 * ctl_perm does NOT grant the superuser all rights automatically, because
1150 * some sysctl variables are readonly even to root.
1153 static int test_perm(int mode
, int op
)
1157 else if (in_egroup_p(0))
1159 if ((mode
& op
& 0007) == op
)
1164 static inline int ctl_perm(ctl_table
*table
, int op
)
1167 error
= security_sysctl(table
, op
);
1170 return test_perm(table
->mode
, op
);
1173 static int parse_table(int __user
*name
, int nlen
,
1174 void __user
*oldval
, size_t __user
*oldlenp
,
1175 void __user
*newval
, size_t newlen
,
1176 ctl_table
*table
, void **context
)
1182 if (get_user(n
, name
))
1184 for ( ; table
->ctl_name
; table
++) {
1185 if (n
== table
->ctl_name
|| table
->ctl_name
== CTL_ANY
) {
1188 if (ctl_perm(table
, 001))
1190 if (table
->strategy
) {
1191 error
= table
->strategy(
1194 newval
, newlen
, context
);
1200 table
= table
->child
;
1203 error
= do_sysctl_strategy(table
, name
, nlen
,
1205 newval
, newlen
, context
);
1212 /* Perform the actual read/write of a sysctl table entry. */
1213 int do_sysctl_strategy (ctl_table
*table
,
1214 int __user
*name
, int nlen
,
1215 void __user
*oldval
, size_t __user
*oldlenp
,
1216 void __user
*newval
, size_t newlen
, void **context
)
1225 if (ctl_perm(table
, op
))
1228 if (table
->strategy
) {
1229 rc
= table
->strategy(table
, name
, nlen
, oldval
, oldlenp
,
1230 newval
, newlen
, context
);
1237 /* If there is no strategy routine, or if the strategy returns
1238 * zero, proceed with automatic r/w */
1239 if (table
->data
&& table
->maxlen
) {
1240 if (oldval
&& oldlenp
) {
1241 if (get_user(len
, oldlenp
))
1244 if (len
> table
->maxlen
)
1245 len
= table
->maxlen
;
1246 if(copy_to_user(oldval
, table
->data
, len
))
1248 if(put_user(len
, oldlenp
))
1252 if (newval
&& newlen
) {
1254 if (len
> table
->maxlen
)
1255 len
= table
->maxlen
;
1256 if(copy_from_user(table
->data
, newval
, len
))
1264 * register_sysctl_table - register a sysctl hierarchy
1265 * @table: the top-level table structure
1266 * @insert_at_head: whether the entry should be inserted in front or at the end
1268 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1269 * array. An entry with a ctl_name of 0 terminates the table.
1271 * The members of the &ctl_table structure are used as follows:
1273 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1274 * must be unique within that level of sysctl
1276 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1277 * enter a sysctl file
1279 * data - a pointer to data for use by proc_handler
1281 * maxlen - the maximum size in bytes of the data
1283 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1285 * child - a pointer to the child sysctl table if this entry is a directory, or
1288 * proc_handler - the text handler routine (described below)
1290 * strategy - the strategy routine (described below)
1292 * de - for internal use by the sysctl routines
1294 * extra1, extra2 - extra pointers usable by the proc handler routines
1296 * Leaf nodes in the sysctl tree will be represented by a single file
1297 * under /proc; non-leaf nodes will be represented by directories.
1299 * sysctl(2) can automatically manage read and write requests through
1300 * the sysctl table. The data and maxlen fields of the ctl_table
1301 * struct enable minimal validation of the values being written to be
1302 * performed, and the mode field allows minimal authentication.
1304 * More sophisticated management can be enabled by the provision of a
1305 * strategy routine with the table entry. This will be called before
1306 * any automatic read or write of the data is performed.
1308 * The strategy routine may return
1310 * < 0 - Error occurred (error is passed to user process)
1312 * 0 - OK - proceed with automatic read or write.
1314 * > 0 - OK - read or write has been done by the strategy routine, so
1315 * return immediately.
1317 * There must be a proc_handler routine for any terminal nodes
1318 * mirrored under /proc/sys (non-terminals are handled by a built-in
1319 * directory handler). Several default handlers are available to
1320 * cover common cases -
1322 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1323 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1324 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1326 * It is the handler's job to read the input buffer from user memory
1327 * and process it. The handler should return 0 on success.
1329 * This routine returns %NULL on a failure to register, and a pointer
1330 * to the table header on success.
1332 struct ctl_table_header
*register_sysctl_table(ctl_table
* table
,
1335 struct ctl_table_header
*tmp
;
1336 tmp
= kmalloc(sizeof(struct ctl_table_header
), GFP_KERNEL
);
1339 tmp
->ctl_table
= table
;
1340 INIT_LIST_HEAD(&tmp
->ctl_entry
);
1342 tmp
->unregistering
= NULL
;
1343 spin_lock(&sysctl_lock
);
1345 list_add(&tmp
->ctl_entry
, &root_table_header
.ctl_entry
);
1347 list_add_tail(&tmp
->ctl_entry
, &root_table_header
.ctl_entry
);
1348 spin_unlock(&sysctl_lock
);
1349 #ifdef CONFIG_PROC_FS
1350 register_proc_table(table
, proc_sys_root
, tmp
);
1356 * unregister_sysctl_table - unregister a sysctl table hierarchy
1357 * @header: the header returned from register_sysctl_table
1359 * Unregisters the sysctl table and all children. proc entries may not
1360 * actually be removed until they are no longer used by anyone.
1362 void unregister_sysctl_table(struct ctl_table_header
* header
)
1365 spin_lock(&sysctl_lock
);
1366 start_unregistering(header
);
1367 #ifdef CONFIG_PROC_FS
1368 unregister_proc_table(header
->ctl_table
, proc_sys_root
);
1370 spin_unlock(&sysctl_lock
);
1378 #ifdef CONFIG_PROC_FS
1380 /* Scan the sysctl entries in table and add them all into /proc */
1381 static void register_proc_table(ctl_table
* table
, struct proc_dir_entry
*root
, void *set
)
1383 struct proc_dir_entry
*de
;
1387 for (; table
->ctl_name
; table
++) {
1388 /* Can't do anything without a proc name. */
1389 if (!table
->procname
)
1391 /* Maybe we can't do anything with it... */
1392 if (!table
->proc_handler
&& !table
->child
) {
1393 printk(KERN_WARNING
"SYSCTL: Can't register %s\n",
1398 len
= strlen(table
->procname
);
1402 if (table
->proc_handler
)
1406 for (de
= root
->subdir
; de
; de
= de
->next
) {
1407 if (proc_match(len
, table
->procname
, de
))
1410 /* If the subdir exists already, de is non-NULL */
1414 de
= create_proc_entry(table
->procname
, mode
, root
);
1418 de
->data
= (void *) table
;
1419 if (table
->proc_handler
)
1420 de
->proc_fops
= &proc_sys_file_operations
;
1423 if (de
->mode
& S_IFDIR
)
1424 register_proc_table(table
->child
, de
, set
);
1429 * Unregister a /proc sysctl table and any subdirectories.
1431 static void unregister_proc_table(ctl_table
* table
, struct proc_dir_entry
*root
)
1433 struct proc_dir_entry
*de
;
1434 for (; table
->ctl_name
; table
++) {
1435 if (!(de
= table
->de
))
1437 if (de
->mode
& S_IFDIR
) {
1438 if (!table
->child
) {
1439 printk (KERN_ALERT
"Help - malformed sysctl tree on free\n");
1442 unregister_proc_table(table
->child
, de
);
1444 /* Don't unregister directories which still have entries.. */
1450 * In any case, mark the entry as goner; we'll keep it
1451 * around if it's busy, but we'll know to do nothing with
1452 * its fields. We are under sysctl_lock here.
1456 /* Don't unregister proc entries that are still being used.. */
1457 if (atomic_read(&de
->count
))
1461 remove_proc_entry(table
->procname
, root
);
1465 static ssize_t
do_rw_proc(int write
, struct file
* file
, char __user
* buf
,
1466 size_t count
, loff_t
*ppos
)
1469 struct proc_dir_entry
*de
= PDE(file
->f_dentry
->d_inode
);
1470 struct ctl_table
*table
;
1472 ssize_t error
= -ENOTDIR
;
1474 spin_lock(&sysctl_lock
);
1475 if (de
&& de
->data
&& use_table(de
->set
)) {
1477 * at that point we know that sysctl was not unregistered
1478 * and won't be until we finish
1480 spin_unlock(&sysctl_lock
);
1481 table
= (struct ctl_table
*) de
->data
;
1482 if (!table
|| !table
->proc_handler
)
1485 op
= (write
? 002 : 004);
1486 if (ctl_perm(table
, op
))
1489 /* careful: calling conventions are nasty here */
1491 error
= (*table
->proc_handler
)(table
, write
, file
,
1496 spin_lock(&sysctl_lock
);
1497 unuse_table(de
->set
);
1499 spin_unlock(&sysctl_lock
);
1503 static int proc_opensys(struct inode
*inode
, struct file
*file
)
1505 if (file
->f_mode
& FMODE_WRITE
) {
1507 * sysctl entries that are not writable,
1508 * are _NOT_ writable, capabilities or not.
1510 if (!(inode
->i_mode
& S_IWUSR
))
1517 static ssize_t
proc_readsys(struct file
* file
, char __user
* buf
,
1518 size_t count
, loff_t
*ppos
)
1520 return do_rw_proc(0, file
, buf
, count
, ppos
);
1523 static ssize_t
proc_writesys(struct file
* file
, const char __user
* buf
,
1524 size_t count
, loff_t
*ppos
)
1526 return do_rw_proc(1, file
, (char __user
*) buf
, count
, ppos
);
1530 * proc_dostring - read a string sysctl
1531 * @table: the sysctl table
1532 * @write: %TRUE if this is a write to the sysctl file
1533 * @filp: the file structure
1534 * @buffer: the user buffer
1535 * @lenp: the size of the user buffer
1536 * @ppos: file position
1538 * Reads/writes a string from/to the user buffer. If the kernel
1539 * buffer provided is not large enough to hold the string, the
1540 * string is truncated. The copied string is %NULL-terminated.
1541 * If the string is being read by the user process, it is copied
1542 * and a newline '\n' is added. It is truncated if the buffer is
1545 * Returns 0 on success.
1547 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
1548 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1554 if (!table
->data
|| !table
->maxlen
|| !*lenp
||
1555 (*ppos
&& !write
)) {
1563 while (len
< *lenp
) {
1564 if (get_user(c
, p
++))
1566 if (c
== 0 || c
== '\n')
1570 if (len
>= table
->maxlen
)
1571 len
= table
->maxlen
-1;
1572 if(copy_from_user(table
->data
, buffer
, len
))
1574 ((char *) table
->data
)[len
] = 0;
1577 len
= strlen(table
->data
);
1578 if (len
> table
->maxlen
)
1579 len
= table
->maxlen
;
1583 if(copy_to_user(buffer
, table
->data
, len
))
1586 if(put_user('\n', ((char __user
*) buffer
) + len
))
1597 * Special case of dostring for the UTS structure. This has locks
1598 * to observe. Should this be in kernel/sys.c ????
1601 static int proc_doutsstring(ctl_table
*table
, int write
, struct file
*filp
,
1602 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1607 down_read(&uts_sem
);
1608 r
=proc_dostring(table
,0,filp
,buffer
,lenp
, ppos
);
1611 down_write(&uts_sem
);
1612 r
=proc_dostring(table
,1,filp
,buffer
,lenp
, ppos
);
1618 static int do_proc_dointvec_conv(int *negp
, unsigned long *lvalp
,
1620 int write
, void *data
)
1623 *valp
= *negp
? -*lvalp
: *lvalp
;
1628 *lvalp
= (unsigned long)-val
;
1631 *lvalp
= (unsigned long)val
;
1637 static int do_proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1638 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
1639 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1640 int write
, void *data
),
1643 #define TMPBUFLEN 21
1644 int *i
, vleft
, first
=1, neg
, val
;
1648 char buf
[TMPBUFLEN
], *p
;
1649 char __user
*s
= buffer
;
1651 if (!table
->data
|| !table
->maxlen
|| !*lenp
||
1652 (*ppos
&& !write
)) {
1657 i
= (int *) table
->data
;
1658 vleft
= table
->maxlen
/ sizeof(*i
);
1662 conv
= do_proc_dointvec_conv
;
1664 for (; left
&& vleft
--; i
++, first
=0) {
1679 if (len
> sizeof(buf
) - 1)
1680 len
= sizeof(buf
) - 1;
1681 if (copy_from_user(buf
, s
, len
))
1685 if (*p
== '-' && left
> 1) {
1689 if (*p
< '0' || *p
> '9')
1692 lval
= simple_strtoul(p
, &p
, 0);
1695 if ((len
< left
) && *p
&& !isspace(*p
))
1702 if (conv(&neg
, &lval
, i
, 1, data
))
1709 if (conv(&neg
, &lval
, i
, 0, data
))
1712 sprintf(p
, "%s%lu", neg
? "-" : "", lval
);
1716 if(copy_to_user(s
, buf
, len
))
1723 if (!write
&& !first
&& left
) {
1724 if(put_user('\n', s
))
1731 if (get_user(c
, s
++))
1747 * proc_dointvec - read a vector of integers
1748 * @table: the sysctl table
1749 * @write: %TRUE if this is a write to the sysctl file
1750 * @filp: the file structure
1751 * @buffer: the user buffer
1752 * @lenp: the size of the user buffer
1753 * @ppos: file position
1755 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1756 * values from/to the user buffer, treated as an ASCII string.
1758 * Returns 0 on success.
1760 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1761 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1763 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1773 static int do_proc_dointvec_bset_conv(int *negp
, unsigned long *lvalp
,
1775 int write
, void *data
)
1777 int op
= *(int *)data
;
1779 int val
= *negp
? -*lvalp
: *lvalp
;
1781 case OP_SET
: *valp
= val
; break;
1782 case OP_AND
: *valp
&= val
; break;
1783 case OP_OR
: *valp
|= val
; break;
1784 case OP_MAX
: if(*valp
< val
)
1787 case OP_MIN
: if(*valp
> val
)
1795 *lvalp
= (unsigned long)-val
;
1798 *lvalp
= (unsigned long)val
;
1805 * init may raise the set.
1808 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
1809 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1813 if (!capable(CAP_SYS_MODULE
)) {
1817 op
= (current
->pid
== 1) ? OP_SET
: OP_AND
;
1818 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1819 do_proc_dointvec_bset_conv
,&op
);
1822 struct do_proc_dointvec_minmax_conv_param
{
1827 static int do_proc_dointvec_minmax_conv(int *negp
, unsigned long *lvalp
,
1829 int write
, void *data
)
1831 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
1833 int val
= *negp
? -*lvalp
: *lvalp
;
1834 if ((param
->min
&& *param
->min
> val
) ||
1835 (param
->max
&& *param
->max
< val
))
1842 *lvalp
= (unsigned long)-val
;
1845 *lvalp
= (unsigned long)val
;
1852 * proc_dointvec_minmax - read a vector of integers with min/max values
1853 * @table: the sysctl table
1854 * @write: %TRUE if this is a write to the sysctl file
1855 * @filp: the file structure
1856 * @buffer: the user buffer
1857 * @lenp: the size of the user buffer
1858 * @ppos: file position
1860 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1861 * values from/to the user buffer, treated as an ASCII string.
1863 * This routine will ensure the values are within the range specified by
1864 * table->extra1 (min) and table->extra2 (max).
1866 * Returns 0 on success.
1868 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
1869 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1871 struct do_proc_dointvec_minmax_conv_param param
= {
1872 .min
= (int *) table
->extra1
,
1873 .max
= (int *) table
->extra2
,
1875 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
1876 do_proc_dointvec_minmax_conv
, ¶m
);
1879 static int do_proc_doulongvec_minmax(ctl_table
*table
, int write
,
1881 void __user
*buffer
,
1882 size_t *lenp
, loff_t
*ppos
,
1883 unsigned long convmul
,
1884 unsigned long convdiv
)
1886 #define TMPBUFLEN 21
1887 unsigned long *i
, *min
, *max
, val
;
1888 int vleft
, first
=1, neg
;
1890 char buf
[TMPBUFLEN
], *p
;
1891 char __user
*s
= buffer
;
1893 if (!table
->data
|| !table
->maxlen
|| !*lenp
||
1894 (*ppos
&& !write
)) {
1899 i
= (unsigned long *) table
->data
;
1900 min
= (unsigned long *) table
->extra1
;
1901 max
= (unsigned long *) table
->extra2
;
1902 vleft
= table
->maxlen
/ sizeof(unsigned long);
1905 for (; left
&& vleft
--; i
++, min
++, max
++, first
=0) {
1920 if (len
> TMPBUFLEN
-1)
1922 if (copy_from_user(buf
, s
, len
))
1926 if (*p
== '-' && left
> 1) {
1930 if (*p
< '0' || *p
> '9')
1932 val
= simple_strtoul(p
, &p
, 0) * convmul
/ convdiv
;
1934 if ((len
< left
) && *p
&& !isspace(*p
))
1943 if ((min
&& val
< *min
) || (max
&& val
> *max
))
1950 sprintf(p
, "%lu", convdiv
* (*i
) / convmul
);
1954 if(copy_to_user(s
, buf
, len
))
1961 if (!write
&& !first
&& left
) {
1962 if(put_user('\n', s
))
1969 if (get_user(c
, s
++))
1985 * proc_doulongvec_minmax - read a vector of long integers with min/max values
1986 * @table: the sysctl table
1987 * @write: %TRUE if this is a write to the sysctl file
1988 * @filp: the file structure
1989 * @buffer: the user buffer
1990 * @lenp: the size of the user buffer
1991 * @ppos: file position
1993 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1994 * values from/to the user buffer, treated as an ASCII string.
1996 * This routine will ensure the values are within the range specified by
1997 * table->extra1 (min) and table->extra2 (max).
1999 * Returns 0 on success.
2001 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2002 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2004 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
, lenp
, ppos
, 1l, 1l);
2008 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2009 * @table: the sysctl table
2010 * @write: %TRUE if this is a write to the sysctl file
2011 * @filp: the file structure
2012 * @buffer: the user buffer
2013 * @lenp: the size of the user buffer
2014 * @ppos: file position
2016 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2017 * values from/to the user buffer, treated as an ASCII string. The values
2018 * are treated as milliseconds, and converted to jiffies when they are stored.
2020 * This routine will ensure the values are within the range specified by
2021 * table->extra1 (min) and table->extra2 (max).
2023 * Returns 0 on success.
2025 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2027 void __user
*buffer
,
2028 size_t *lenp
, loff_t
*ppos
)
2030 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
,
2031 lenp
, ppos
, HZ
, 1000l);
2035 static int do_proc_dointvec_jiffies_conv(int *negp
, unsigned long *lvalp
,
2037 int write
, void *data
)
2040 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2046 lval
= (unsigned long)-val
;
2049 lval
= (unsigned long)val
;
2056 static int do_proc_dointvec_userhz_jiffies_conv(int *negp
, unsigned long *lvalp
,
2058 int write
, void *data
)
2061 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2067 lval
= (unsigned long)-val
;
2070 lval
= (unsigned long)val
;
2072 *lvalp
= jiffies_to_clock_t(lval
);
2077 static int do_proc_dointvec_ms_jiffies_conv(int *negp
, unsigned long *lvalp
,
2079 int write
, void *data
)
2082 *valp
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2088 lval
= (unsigned long)-val
;
2091 lval
= (unsigned long)val
;
2093 *lvalp
= jiffies_to_msecs(lval
);
2099 * proc_dointvec_jiffies - read a vector of integers as seconds
2100 * @table: the sysctl table
2101 * @write: %TRUE if this is a write to the sysctl file
2102 * @filp: the file structure
2103 * @buffer: the user buffer
2104 * @lenp: the size of the user buffer
2105 * @ppos: file position
2107 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2108 * values from/to the user buffer, treated as an ASCII string.
2109 * The values read are assumed to be in seconds, and are converted into
2112 * Returns 0 on success.
2114 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2115 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2117 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2118 do_proc_dointvec_jiffies_conv
,NULL
);
2122 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2123 * @table: the sysctl table
2124 * @write: %TRUE if this is a write to the sysctl file
2125 * @filp: the file structure
2126 * @buffer: the user buffer
2127 * @lenp: the size of the user buffer
2128 * @ppos: pointer to the file position
2130 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2131 * values from/to the user buffer, treated as an ASCII string.
2132 * The values read are assumed to be in 1/USER_HZ seconds, and
2133 * are converted into jiffies.
2135 * Returns 0 on success.
2137 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2138 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2140 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2141 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2145 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2146 * @table: the sysctl table
2147 * @write: %TRUE if this is a write to the sysctl file
2148 * @filp: the file structure
2149 * @buffer: the user buffer
2150 * @lenp: the size of the user buffer
2151 * @ppos: file position
2152 * @ppos: the current position in the file
2154 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2155 * values from/to the user buffer, treated as an ASCII string.
2156 * The values read are assumed to be in 1/1000 seconds, and
2157 * are converted into jiffies.
2159 * Returns 0 on success.
2161 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2162 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2164 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2165 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2168 #else /* CONFIG_PROC_FS */
2170 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
2171 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2176 static int proc_doutsstring(ctl_table
*table
, int write
, struct file
*filp
,
2177 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2182 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
2183 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2188 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
2189 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2194 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2195 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2200 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2201 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2206 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2207 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2212 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2213 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2218 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2219 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2224 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2226 void __user
*buffer
,
2227 size_t *lenp
, loff_t
*ppos
)
2233 #endif /* CONFIG_PROC_FS */
2237 * General sysctl support routines
2240 /* The generic string strategy routine: */
2241 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2242 void __user
*oldval
, size_t __user
*oldlenp
,
2243 void __user
*newval
, size_t newlen
, void **context
)
2245 if (!table
->data
|| !table
->maxlen
)
2248 if (oldval
&& oldlenp
) {
2250 if (get_user(bufsize
, oldlenp
))
2253 size_t len
= strlen(table
->data
), copied
;
2255 /* This shouldn't trigger for a well-formed sysctl */
2256 if (len
> table
->maxlen
)
2257 len
= table
->maxlen
;
2259 /* Copy up to a max of bufsize-1 bytes of the string */
2260 copied
= (len
>= bufsize
) ? bufsize
- 1 : len
;
2262 if (copy_to_user(oldval
, table
->data
, copied
) ||
2263 put_user(0, (char __user
*)(oldval
+ copied
)))
2265 if (put_user(len
, oldlenp
))
2269 if (newval
&& newlen
) {
2270 size_t len
= newlen
;
2271 if (len
> table
->maxlen
)
2272 len
= table
->maxlen
;
2273 if(copy_from_user(table
->data
, newval
, len
))
2275 if (len
== table
->maxlen
)
2277 ((char *) table
->data
)[len
] = 0;
2283 * This function makes sure that all of the integers in the vector
2284 * are between the minimum and maximum values given in the arrays
2285 * table->extra1 and table->extra2, respectively.
2287 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2288 void __user
*oldval
, size_t __user
*oldlenp
,
2289 void __user
*newval
, size_t newlen
, void **context
)
2292 if (newval
&& newlen
) {
2293 int __user
*vec
= (int __user
*) newval
;
2294 int *min
= (int *) table
->extra1
;
2295 int *max
= (int *) table
->extra2
;
2299 if (newlen
% sizeof(int) != 0)
2302 if (!table
->extra1
&& !table
->extra2
)
2305 if (newlen
> table
->maxlen
)
2306 newlen
= table
->maxlen
;
2307 length
= newlen
/ sizeof(int);
2309 for (i
= 0; i
< length
; i
++) {
2311 if (get_user(value
, vec
+ i
))
2313 if (min
&& value
< min
[i
])
2315 if (max
&& value
> max
[i
])
2322 /* Strategy function to convert jiffies to seconds */
2323 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2324 void __user
*oldval
, size_t __user
*oldlenp
,
2325 void __user
*newval
, size_t newlen
, void **context
)
2330 if (get_user(olen
, oldlenp
))
2332 if (olen
!=sizeof(int))
2335 if (put_user(*(int *)(table
->data
)/HZ
, (int __user
*)oldval
) ||
2336 (oldlenp
&& put_user(sizeof(int),oldlenp
)))
2339 if (newval
&& newlen
) {
2341 if (newlen
!= sizeof(int))
2343 if (get_user(new, (int __user
*)newval
))
2345 *(int *)(table
->data
) = new*HZ
;
2350 /* Strategy function to convert jiffies to seconds */
2351 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2352 void __user
*oldval
, size_t __user
*oldlenp
,
2353 void __user
*newval
, size_t newlen
, void **context
)
2358 if (get_user(olen
, oldlenp
))
2360 if (olen
!=sizeof(int))
2363 if (put_user(jiffies_to_msecs(*(int *)(table
->data
)), (int __user
*)oldval
) ||
2364 (oldlenp
&& put_user(sizeof(int),oldlenp
)))
2367 if (newval
&& newlen
) {
2369 if (newlen
!= sizeof(int))
2371 if (get_user(new, (int __user
*)newval
))
2373 *(int *)(table
->data
) = msecs_to_jiffies(new);
2378 #else /* CONFIG_SYSCTL */
2381 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
2386 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2387 void __user
*oldval
, size_t __user
*oldlenp
,
2388 void __user
*newval
, size_t newlen
, void **context
)
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
, void **context
)
2400 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2401 void __user
*oldval
, size_t __user
*oldlenp
,
2402 void __user
*newval
, size_t newlen
, void **context
)
2407 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2408 void __user
*oldval
, size_t __user
*oldlenp
,
2409 void __user
*newval
, size_t newlen
, void **context
)
2414 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
2415 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2420 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
2421 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2426 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
2427 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2432 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2433 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2438 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2439 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2444 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2445 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2450 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2451 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2456 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2457 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2462 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2464 void __user
*buffer
,
2465 size_t *lenp
, loff_t
*ppos
)
2470 struct ctl_table_header
* register_sysctl_table(ctl_table
* table
,
2476 void unregister_sysctl_table(struct ctl_table_header
* table
)
2480 #endif /* CONFIG_SYSCTL */
2483 * No sense putting this after each symbol definition, twice,
2484 * exception granted :-)
2486 EXPORT_SYMBOL(proc_dointvec
);
2487 EXPORT_SYMBOL(proc_dointvec_jiffies
);
2488 EXPORT_SYMBOL(proc_dointvec_minmax
);
2489 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
2490 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
2491 EXPORT_SYMBOL(proc_dostring
);
2492 EXPORT_SYMBOL(proc_doulongvec_minmax
);
2493 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);
2494 EXPORT_SYMBOL(register_sysctl_table
);
2495 EXPORT_SYMBOL(sysctl_intvec
);
2496 EXPORT_SYMBOL(sysctl_jiffies
);
2497 EXPORT_SYMBOL(sysctl_ms_jiffies
);
2498 EXPORT_SYMBOL(sysctl_string
);
2499 EXPORT_SYMBOL(unregister_sysctl_table
);