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
,
949 .ctl_name
= VM_VDSO_ENABLED
,
950 .procname
= "vdso_enabled",
951 .data
= &vdso_enabled
,
952 .maxlen
= sizeof(vdso_enabled
),
954 .proc_handler
= &proc_dointvec
,
955 .strategy
= &sysctl_intvec
,
962 static ctl_table fs_table
[] = {
964 .ctl_name
= FS_NRINODE
,
965 .procname
= "inode-nr",
966 .data
= &inodes_stat
,
967 .maxlen
= 2*sizeof(int),
969 .proc_handler
= &proc_dointvec
,
972 .ctl_name
= FS_STATINODE
,
973 .procname
= "inode-state",
974 .data
= &inodes_stat
,
975 .maxlen
= 7*sizeof(int),
977 .proc_handler
= &proc_dointvec
,
980 .ctl_name
= FS_NRFILE
,
981 .procname
= "file-nr",
983 .maxlen
= 3*sizeof(int),
985 .proc_handler
= &proc_nr_files
,
988 .ctl_name
= FS_MAXFILE
,
989 .procname
= "file-max",
990 .data
= &files_stat
.max_files
,
991 .maxlen
= sizeof(int),
993 .proc_handler
= &proc_dointvec
,
996 .ctl_name
= FS_DENTRY
,
997 .procname
= "dentry-state",
998 .data
= &dentry_stat
,
999 .maxlen
= 6*sizeof(int),
1001 .proc_handler
= &proc_dointvec
,
1004 .ctl_name
= FS_OVERFLOWUID
,
1005 .procname
= "overflowuid",
1006 .data
= &fs_overflowuid
,
1007 .maxlen
= sizeof(int),
1009 .proc_handler
= &proc_dointvec_minmax
,
1010 .strategy
= &sysctl_intvec
,
1011 .extra1
= &minolduid
,
1012 .extra2
= &maxolduid
,
1015 .ctl_name
= FS_OVERFLOWGID
,
1016 .procname
= "overflowgid",
1017 .data
= &fs_overflowgid
,
1018 .maxlen
= sizeof(int),
1020 .proc_handler
= &proc_dointvec_minmax
,
1021 .strategy
= &sysctl_intvec
,
1022 .extra1
= &minolduid
,
1023 .extra2
= &maxolduid
,
1026 .ctl_name
= FS_LEASES
,
1027 .procname
= "leases-enable",
1028 .data
= &leases_enable
,
1029 .maxlen
= sizeof(int),
1031 .proc_handler
= &proc_dointvec
,
1033 #ifdef CONFIG_DNOTIFY
1035 .ctl_name
= FS_DIR_NOTIFY
,
1036 .procname
= "dir-notify-enable",
1037 .data
= &dir_notify_enable
,
1038 .maxlen
= sizeof(int),
1040 .proc_handler
= &proc_dointvec
,
1045 .ctl_name
= FS_LEASE_TIME
,
1046 .procname
= "lease-break-time",
1047 .data
= &lease_break_time
,
1048 .maxlen
= sizeof(int),
1050 .proc_handler
= &proc_dointvec
,
1053 .ctl_name
= FS_AIO_NR
,
1054 .procname
= "aio-nr",
1056 .maxlen
= sizeof(aio_nr
),
1058 .proc_handler
= &proc_doulongvec_minmax
,
1061 .ctl_name
= FS_AIO_MAX_NR
,
1062 .procname
= "aio-max-nr",
1063 .data
= &aio_max_nr
,
1064 .maxlen
= sizeof(aio_max_nr
),
1066 .proc_handler
= &proc_doulongvec_minmax
,
1068 #ifdef CONFIG_INOTIFY_USER
1070 .ctl_name
= FS_INOTIFY
,
1071 .procname
= "inotify",
1073 .child
= inotify_table
,
1078 .ctl_name
= KERN_SETUID_DUMPABLE
,
1079 .procname
= "suid_dumpable",
1080 .data
= &suid_dumpable
,
1081 .maxlen
= sizeof(int),
1083 .proc_handler
= &proc_dointvec
,
1088 static ctl_table debug_table
[] = {
1092 static ctl_table dev_table
[] = {
1096 extern void init_irq_proc (void);
1098 static DEFINE_SPINLOCK(sysctl_lock
);
1100 /* called under sysctl_lock */
1101 static int use_table(struct ctl_table_header
*p
)
1103 if (unlikely(p
->unregistering
))
1109 /* called under sysctl_lock */
1110 static void unuse_table(struct ctl_table_header
*p
)
1113 if (unlikely(p
->unregistering
))
1114 complete(p
->unregistering
);
1117 /* called under sysctl_lock, will reacquire if has to wait */
1118 static void start_unregistering(struct ctl_table_header
*p
)
1121 * if p->used is 0, nobody will ever touch that entry again;
1122 * we'll eliminate all paths to it before dropping sysctl_lock
1124 if (unlikely(p
->used
)) {
1125 struct completion wait
;
1126 init_completion(&wait
);
1127 p
->unregistering
= &wait
;
1128 spin_unlock(&sysctl_lock
);
1129 wait_for_completion(&wait
);
1130 spin_lock(&sysctl_lock
);
1133 * do not remove from the list until nobody holds it; walking the
1134 * list in do_sysctl() relies on that.
1136 list_del_init(&p
->ctl_entry
);
1139 void __init
sysctl_init(void)
1141 #ifdef CONFIG_PROC_FS
1142 register_proc_table(root_table
, proc_sys_root
, &root_table_header
);
1147 int do_sysctl(int __user
*name
, int nlen
, void __user
*oldval
, size_t __user
*oldlenp
,
1148 void __user
*newval
, size_t newlen
)
1150 struct list_head
*tmp
;
1151 int error
= -ENOTDIR
;
1153 if (nlen
<= 0 || nlen
>= CTL_MAXNAME
)
1157 if (!oldlenp
|| get_user(old_len
, oldlenp
))
1160 spin_lock(&sysctl_lock
);
1161 tmp
= &root_table_header
.ctl_entry
;
1163 struct ctl_table_header
*head
=
1164 list_entry(tmp
, struct ctl_table_header
, ctl_entry
);
1165 void *context
= NULL
;
1167 if (!use_table(head
))
1170 spin_unlock(&sysctl_lock
);
1172 error
= parse_table(name
, nlen
, oldval
, oldlenp
,
1173 newval
, newlen
, head
->ctl_table
,
1177 spin_lock(&sysctl_lock
);
1179 if (error
!= -ENOTDIR
)
1181 } while ((tmp
= tmp
->next
) != &root_table_header
.ctl_entry
);
1182 spin_unlock(&sysctl_lock
);
1186 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
1188 struct __sysctl_args tmp
;
1191 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
1195 error
= do_sysctl(tmp
.name
, tmp
.nlen
, tmp
.oldval
, tmp
.oldlenp
,
1196 tmp
.newval
, tmp
.newlen
);
1202 * ctl_perm does NOT grant the superuser all rights automatically, because
1203 * some sysctl variables are readonly even to root.
1206 static int test_perm(int mode
, int op
)
1210 else if (in_egroup_p(0))
1212 if ((mode
& op
& 0007) == op
)
1217 static inline int ctl_perm(ctl_table
*table
, int op
)
1220 error
= security_sysctl(table
, op
);
1223 return test_perm(table
->mode
, op
);
1226 static int parse_table(int __user
*name
, int nlen
,
1227 void __user
*oldval
, size_t __user
*oldlenp
,
1228 void __user
*newval
, size_t newlen
,
1229 ctl_table
*table
, void **context
)
1235 if (get_user(n
, name
))
1237 for ( ; table
->ctl_name
; table
++) {
1238 if (n
== table
->ctl_name
|| table
->ctl_name
== CTL_ANY
) {
1241 if (ctl_perm(table
, 001))
1243 if (table
->strategy
) {
1244 error
= table
->strategy(
1247 newval
, newlen
, context
);
1253 table
= table
->child
;
1256 error
= do_sysctl_strategy(table
, name
, nlen
,
1258 newval
, newlen
, context
);
1265 /* Perform the actual read/write of a sysctl table entry. */
1266 int do_sysctl_strategy (ctl_table
*table
,
1267 int __user
*name
, int nlen
,
1268 void __user
*oldval
, size_t __user
*oldlenp
,
1269 void __user
*newval
, size_t newlen
, void **context
)
1278 if (ctl_perm(table
, op
))
1281 if (table
->strategy
) {
1282 rc
= table
->strategy(table
, name
, nlen
, oldval
, oldlenp
,
1283 newval
, newlen
, context
);
1290 /* If there is no strategy routine, or if the strategy returns
1291 * zero, proceed with automatic r/w */
1292 if (table
->data
&& table
->maxlen
) {
1293 if (oldval
&& oldlenp
) {
1294 if (get_user(len
, oldlenp
))
1297 if (len
> table
->maxlen
)
1298 len
= table
->maxlen
;
1299 if(copy_to_user(oldval
, table
->data
, len
))
1301 if(put_user(len
, oldlenp
))
1305 if (newval
&& newlen
) {
1307 if (len
> table
->maxlen
)
1308 len
= table
->maxlen
;
1309 if(copy_from_user(table
->data
, newval
, len
))
1317 * register_sysctl_table - register a sysctl hierarchy
1318 * @table: the top-level table structure
1319 * @insert_at_head: whether the entry should be inserted in front or at the end
1321 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1322 * array. An entry with a ctl_name of 0 terminates the table.
1324 * The members of the &ctl_table structure are used as follows:
1326 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1327 * must be unique within that level of sysctl
1329 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1330 * enter a sysctl file
1332 * data - a pointer to data for use by proc_handler
1334 * maxlen - the maximum size in bytes of the data
1336 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1338 * child - a pointer to the child sysctl table if this entry is a directory, or
1341 * proc_handler - the text handler routine (described below)
1343 * strategy - the strategy routine (described below)
1345 * de - for internal use by the sysctl routines
1347 * extra1, extra2 - extra pointers usable by the proc handler routines
1349 * Leaf nodes in the sysctl tree will be represented by a single file
1350 * under /proc; non-leaf nodes will be represented by directories.
1352 * sysctl(2) can automatically manage read and write requests through
1353 * the sysctl table. The data and maxlen fields of the ctl_table
1354 * struct enable minimal validation of the values being written to be
1355 * performed, and the mode field allows minimal authentication.
1357 * More sophisticated management can be enabled by the provision of a
1358 * strategy routine with the table entry. This will be called before
1359 * any automatic read or write of the data is performed.
1361 * The strategy routine may return
1363 * < 0 - Error occurred (error is passed to user process)
1365 * 0 - OK - proceed with automatic read or write.
1367 * > 0 - OK - read or write has been done by the strategy routine, so
1368 * return immediately.
1370 * There must be a proc_handler routine for any terminal nodes
1371 * mirrored under /proc/sys (non-terminals are handled by a built-in
1372 * directory handler). Several default handlers are available to
1373 * cover common cases -
1375 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1376 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1377 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1379 * It is the handler's job to read the input buffer from user memory
1380 * and process it. The handler should return 0 on success.
1382 * This routine returns %NULL on a failure to register, and a pointer
1383 * to the table header on success.
1385 struct ctl_table_header
*register_sysctl_table(ctl_table
* table
,
1388 struct ctl_table_header
*tmp
;
1389 tmp
= kmalloc(sizeof(struct ctl_table_header
), GFP_KERNEL
);
1392 tmp
->ctl_table
= table
;
1393 INIT_LIST_HEAD(&tmp
->ctl_entry
);
1395 tmp
->unregistering
= NULL
;
1396 spin_lock(&sysctl_lock
);
1398 list_add(&tmp
->ctl_entry
, &root_table_header
.ctl_entry
);
1400 list_add_tail(&tmp
->ctl_entry
, &root_table_header
.ctl_entry
);
1401 spin_unlock(&sysctl_lock
);
1402 #ifdef CONFIG_PROC_FS
1403 register_proc_table(table
, proc_sys_root
, tmp
);
1409 * unregister_sysctl_table - unregister a sysctl table hierarchy
1410 * @header: the header returned from register_sysctl_table
1412 * Unregisters the sysctl table and all children. proc entries may not
1413 * actually be removed until they are no longer used by anyone.
1415 void unregister_sysctl_table(struct ctl_table_header
* header
)
1418 spin_lock(&sysctl_lock
);
1419 start_unregistering(header
);
1420 #ifdef CONFIG_PROC_FS
1421 unregister_proc_table(header
->ctl_table
, proc_sys_root
);
1423 spin_unlock(&sysctl_lock
);
1431 #ifdef CONFIG_PROC_FS
1433 /* Scan the sysctl entries in table and add them all into /proc */
1434 static void register_proc_table(ctl_table
* table
, struct proc_dir_entry
*root
, void *set
)
1436 struct proc_dir_entry
*de
;
1440 for (; table
->ctl_name
; table
++) {
1441 /* Can't do anything without a proc name. */
1442 if (!table
->procname
)
1444 /* Maybe we can't do anything with it... */
1445 if (!table
->proc_handler
&& !table
->child
) {
1446 printk(KERN_WARNING
"SYSCTL: Can't register %s\n",
1451 len
= strlen(table
->procname
);
1455 if (table
->proc_handler
)
1459 for (de
= root
->subdir
; de
; de
= de
->next
) {
1460 if (proc_match(len
, table
->procname
, de
))
1463 /* If the subdir exists already, de is non-NULL */
1467 de
= create_proc_entry(table
->procname
, mode
, root
);
1471 de
->data
= (void *) table
;
1472 if (table
->proc_handler
)
1473 de
->proc_fops
= &proc_sys_file_operations
;
1476 if (de
->mode
& S_IFDIR
)
1477 register_proc_table(table
->child
, de
, set
);
1482 * Unregister a /proc sysctl table and any subdirectories.
1484 static void unregister_proc_table(ctl_table
* table
, struct proc_dir_entry
*root
)
1486 struct proc_dir_entry
*de
;
1487 for (; table
->ctl_name
; table
++) {
1488 if (!(de
= table
->de
))
1490 if (de
->mode
& S_IFDIR
) {
1491 if (!table
->child
) {
1492 printk (KERN_ALERT
"Help - malformed sysctl tree on free\n");
1495 unregister_proc_table(table
->child
, de
);
1497 /* Don't unregister directories which still have entries.. */
1503 * In any case, mark the entry as goner; we'll keep it
1504 * around if it's busy, but we'll know to do nothing with
1505 * its fields. We are under sysctl_lock here.
1509 /* Don't unregister proc entries that are still being used.. */
1510 if (atomic_read(&de
->count
))
1514 remove_proc_entry(table
->procname
, root
);
1518 static ssize_t
do_rw_proc(int write
, struct file
* file
, char __user
* buf
,
1519 size_t count
, loff_t
*ppos
)
1522 struct proc_dir_entry
*de
= PDE(file
->f_dentry
->d_inode
);
1523 struct ctl_table
*table
;
1525 ssize_t error
= -ENOTDIR
;
1527 spin_lock(&sysctl_lock
);
1528 if (de
&& de
->data
&& use_table(de
->set
)) {
1530 * at that point we know that sysctl was not unregistered
1531 * and won't be until we finish
1533 spin_unlock(&sysctl_lock
);
1534 table
= (struct ctl_table
*) de
->data
;
1535 if (!table
|| !table
->proc_handler
)
1538 op
= (write
? 002 : 004);
1539 if (ctl_perm(table
, op
))
1542 /* careful: calling conventions are nasty here */
1544 error
= (*table
->proc_handler
)(table
, write
, file
,
1549 spin_lock(&sysctl_lock
);
1550 unuse_table(de
->set
);
1552 spin_unlock(&sysctl_lock
);
1556 static int proc_opensys(struct inode
*inode
, struct file
*file
)
1558 if (file
->f_mode
& FMODE_WRITE
) {
1560 * sysctl entries that are not writable,
1561 * are _NOT_ writable, capabilities or not.
1563 if (!(inode
->i_mode
& S_IWUSR
))
1570 static ssize_t
proc_readsys(struct file
* file
, char __user
* buf
,
1571 size_t count
, loff_t
*ppos
)
1573 return do_rw_proc(0, file
, buf
, count
, ppos
);
1576 static ssize_t
proc_writesys(struct file
* file
, const char __user
* buf
,
1577 size_t count
, loff_t
*ppos
)
1579 return do_rw_proc(1, file
, (char __user
*) buf
, count
, ppos
);
1583 * proc_dostring - read a string sysctl
1584 * @table: the sysctl table
1585 * @write: %TRUE if this is a write to the sysctl file
1586 * @filp: the file structure
1587 * @buffer: the user buffer
1588 * @lenp: the size of the user buffer
1589 * @ppos: file position
1591 * Reads/writes a string from/to the user buffer. If the kernel
1592 * buffer provided is not large enough to hold the string, the
1593 * string is truncated. The copied string is %NULL-terminated.
1594 * If the string is being read by the user process, it is copied
1595 * and a newline '\n' is added. It is truncated if the buffer is
1598 * Returns 0 on success.
1600 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
1601 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1607 if (!table
->data
|| !table
->maxlen
|| !*lenp
||
1608 (*ppos
&& !write
)) {
1616 while (len
< *lenp
) {
1617 if (get_user(c
, p
++))
1619 if (c
== 0 || c
== '\n')
1623 if (len
>= table
->maxlen
)
1624 len
= table
->maxlen
-1;
1625 if(copy_from_user(table
->data
, buffer
, len
))
1627 ((char *) table
->data
)[len
] = 0;
1630 len
= strlen(table
->data
);
1631 if (len
> table
->maxlen
)
1632 len
= table
->maxlen
;
1636 if(copy_to_user(buffer
, table
->data
, len
))
1639 if(put_user('\n', ((char __user
*) buffer
) + len
))
1650 * Special case of dostring for the UTS structure. This has locks
1651 * to observe. Should this be in kernel/sys.c ????
1654 static int proc_doutsstring(ctl_table
*table
, int write
, struct file
*filp
,
1655 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1660 down_read(&uts_sem
);
1661 r
=proc_dostring(table
,0,filp
,buffer
,lenp
, ppos
);
1664 down_write(&uts_sem
);
1665 r
=proc_dostring(table
,1,filp
,buffer
,lenp
, ppos
);
1671 static int do_proc_dointvec_conv(int *negp
, unsigned long *lvalp
,
1673 int write
, void *data
)
1676 *valp
= *negp
? -*lvalp
: *lvalp
;
1681 *lvalp
= (unsigned long)-val
;
1684 *lvalp
= (unsigned long)val
;
1690 static int do_proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1691 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
1692 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1693 int write
, void *data
),
1696 #define TMPBUFLEN 21
1697 int *i
, vleft
, first
=1, neg
, val
;
1701 char buf
[TMPBUFLEN
], *p
;
1702 char __user
*s
= buffer
;
1704 if (!table
->data
|| !table
->maxlen
|| !*lenp
||
1705 (*ppos
&& !write
)) {
1710 i
= (int *) table
->data
;
1711 vleft
= table
->maxlen
/ sizeof(*i
);
1715 conv
= do_proc_dointvec_conv
;
1717 for (; left
&& vleft
--; i
++, first
=0) {
1732 if (len
> sizeof(buf
) - 1)
1733 len
= sizeof(buf
) - 1;
1734 if (copy_from_user(buf
, s
, len
))
1738 if (*p
== '-' && left
> 1) {
1742 if (*p
< '0' || *p
> '9')
1745 lval
= simple_strtoul(p
, &p
, 0);
1748 if ((len
< left
) && *p
&& !isspace(*p
))
1755 if (conv(&neg
, &lval
, i
, 1, data
))
1762 if (conv(&neg
, &lval
, i
, 0, data
))
1765 sprintf(p
, "%s%lu", neg
? "-" : "", lval
);
1769 if(copy_to_user(s
, buf
, len
))
1776 if (!write
&& !first
&& left
) {
1777 if(put_user('\n', s
))
1784 if (get_user(c
, s
++))
1800 * proc_dointvec - read a vector of integers
1801 * @table: the sysctl table
1802 * @write: %TRUE if this is a write to the sysctl file
1803 * @filp: the file structure
1804 * @buffer: the user buffer
1805 * @lenp: the size of the user buffer
1806 * @ppos: file position
1808 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1809 * values from/to the user buffer, treated as an ASCII string.
1811 * Returns 0 on success.
1813 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1814 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1816 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1826 static int do_proc_dointvec_bset_conv(int *negp
, unsigned long *lvalp
,
1828 int write
, void *data
)
1830 int op
= *(int *)data
;
1832 int val
= *negp
? -*lvalp
: *lvalp
;
1834 case OP_SET
: *valp
= val
; break;
1835 case OP_AND
: *valp
&= val
; break;
1836 case OP_OR
: *valp
|= val
; break;
1837 case OP_MAX
: if(*valp
< val
)
1840 case OP_MIN
: if(*valp
> val
)
1848 *lvalp
= (unsigned long)-val
;
1851 *lvalp
= (unsigned long)val
;
1858 * init may raise the set.
1861 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
1862 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1866 if (!capable(CAP_SYS_MODULE
)) {
1870 op
= (current
->pid
== 1) ? OP_SET
: OP_AND
;
1871 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1872 do_proc_dointvec_bset_conv
,&op
);
1875 struct do_proc_dointvec_minmax_conv_param
{
1880 static int do_proc_dointvec_minmax_conv(int *negp
, unsigned long *lvalp
,
1882 int write
, void *data
)
1884 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
1886 int val
= *negp
? -*lvalp
: *lvalp
;
1887 if ((param
->min
&& *param
->min
> val
) ||
1888 (param
->max
&& *param
->max
< val
))
1895 *lvalp
= (unsigned long)-val
;
1898 *lvalp
= (unsigned long)val
;
1905 * proc_dointvec_minmax - read a vector of integers with min/max values
1906 * @table: the sysctl table
1907 * @write: %TRUE if this is a write to the sysctl file
1908 * @filp: the file structure
1909 * @buffer: the user buffer
1910 * @lenp: the size of the user buffer
1911 * @ppos: file position
1913 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1914 * values from/to the user buffer, treated as an ASCII string.
1916 * This routine will ensure the values are within the range specified by
1917 * table->extra1 (min) and table->extra2 (max).
1919 * Returns 0 on success.
1921 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
1922 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1924 struct do_proc_dointvec_minmax_conv_param param
= {
1925 .min
= (int *) table
->extra1
,
1926 .max
= (int *) table
->extra2
,
1928 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
1929 do_proc_dointvec_minmax_conv
, ¶m
);
1932 static int do_proc_doulongvec_minmax(ctl_table
*table
, int write
,
1934 void __user
*buffer
,
1935 size_t *lenp
, loff_t
*ppos
,
1936 unsigned long convmul
,
1937 unsigned long convdiv
)
1939 #define TMPBUFLEN 21
1940 unsigned long *i
, *min
, *max
, val
;
1941 int vleft
, first
=1, neg
;
1943 char buf
[TMPBUFLEN
], *p
;
1944 char __user
*s
= buffer
;
1946 if (!table
->data
|| !table
->maxlen
|| !*lenp
||
1947 (*ppos
&& !write
)) {
1952 i
= (unsigned long *) table
->data
;
1953 min
= (unsigned long *) table
->extra1
;
1954 max
= (unsigned long *) table
->extra2
;
1955 vleft
= table
->maxlen
/ sizeof(unsigned long);
1958 for (; left
&& vleft
--; i
++, min
++, max
++, first
=0) {
1973 if (len
> TMPBUFLEN
-1)
1975 if (copy_from_user(buf
, s
, len
))
1979 if (*p
== '-' && left
> 1) {
1983 if (*p
< '0' || *p
> '9')
1985 val
= simple_strtoul(p
, &p
, 0) * convmul
/ convdiv
;
1987 if ((len
< left
) && *p
&& !isspace(*p
))
1996 if ((min
&& val
< *min
) || (max
&& val
> *max
))
2003 sprintf(p
, "%lu", convdiv
* (*i
) / convmul
);
2007 if(copy_to_user(s
, buf
, len
))
2014 if (!write
&& !first
&& left
) {
2015 if(put_user('\n', s
))
2022 if (get_user(c
, s
++))
2038 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2039 * @table: the sysctl table
2040 * @write: %TRUE if this is a write to the sysctl file
2041 * @filp: the file structure
2042 * @buffer: the user buffer
2043 * @lenp: the size of the user buffer
2044 * @ppos: file position
2046 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2047 * values from/to the user buffer, treated as an ASCII string.
2049 * This routine will ensure the values are within the range specified by
2050 * table->extra1 (min) and table->extra2 (max).
2052 * Returns 0 on success.
2054 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2055 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2057 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
, lenp
, ppos
, 1l, 1l);
2061 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2062 * @table: the sysctl table
2063 * @write: %TRUE if this is a write to the sysctl file
2064 * @filp: the file structure
2065 * @buffer: the user buffer
2066 * @lenp: the size of the user buffer
2067 * @ppos: file position
2069 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2070 * values from/to the user buffer, treated as an ASCII string. The values
2071 * are treated as milliseconds, and converted to jiffies when they are stored.
2073 * This routine will ensure the values are within the range specified by
2074 * table->extra1 (min) and table->extra2 (max).
2076 * Returns 0 on success.
2078 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2080 void __user
*buffer
,
2081 size_t *lenp
, loff_t
*ppos
)
2083 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
,
2084 lenp
, ppos
, HZ
, 1000l);
2088 static int do_proc_dointvec_jiffies_conv(int *negp
, unsigned long *lvalp
,
2090 int write
, void *data
)
2093 if (*lvalp
> LONG_MAX
/ HZ
)
2095 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2101 lval
= (unsigned long)-val
;
2104 lval
= (unsigned long)val
;
2111 static int do_proc_dointvec_userhz_jiffies_conv(int *negp
, unsigned long *lvalp
,
2113 int write
, void *data
)
2116 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2118 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2124 lval
= (unsigned long)-val
;
2127 lval
= (unsigned long)val
;
2129 *lvalp
= jiffies_to_clock_t(lval
);
2134 static int do_proc_dointvec_ms_jiffies_conv(int *negp
, unsigned long *lvalp
,
2136 int write
, void *data
)
2139 *valp
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2145 lval
= (unsigned long)-val
;
2148 lval
= (unsigned long)val
;
2150 *lvalp
= jiffies_to_msecs(lval
);
2156 * proc_dointvec_jiffies - read a vector of integers as seconds
2157 * @table: the sysctl table
2158 * @write: %TRUE if this is a write to the sysctl file
2159 * @filp: the file structure
2160 * @buffer: the user buffer
2161 * @lenp: the size of the user buffer
2162 * @ppos: file position
2164 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2165 * values from/to the user buffer, treated as an ASCII string.
2166 * The values read are assumed to be in seconds, and are converted into
2169 * Returns 0 on success.
2171 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2172 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2174 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2175 do_proc_dointvec_jiffies_conv
,NULL
);
2179 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2180 * @table: the sysctl table
2181 * @write: %TRUE if this is a write to the sysctl file
2182 * @filp: the file structure
2183 * @buffer: the user buffer
2184 * @lenp: the size of the user buffer
2185 * @ppos: pointer to the file position
2187 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2188 * values from/to the user buffer, treated as an ASCII string.
2189 * The values read are assumed to be in 1/USER_HZ seconds, and
2190 * are converted into jiffies.
2192 * Returns 0 on success.
2194 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2195 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2197 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2198 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2202 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2203 * @table: the sysctl table
2204 * @write: %TRUE if this is a write to the sysctl file
2205 * @filp: the file structure
2206 * @buffer: the user buffer
2207 * @lenp: the size of the user buffer
2208 * @ppos: file position
2209 * @ppos: the current position in the file
2211 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2212 * values from/to the user buffer, treated as an ASCII string.
2213 * The values read are assumed to be in 1/1000 seconds, and
2214 * are converted into jiffies.
2216 * Returns 0 on success.
2218 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2219 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2221 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2222 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2225 #else /* CONFIG_PROC_FS */
2227 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
2228 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2233 static int proc_doutsstring(ctl_table
*table
, int write
, struct file
*filp
,
2234 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2239 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
2240 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2245 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
2246 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2251 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2252 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2257 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2258 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2263 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2264 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2269 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2270 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2275 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2276 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2281 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2283 void __user
*buffer
,
2284 size_t *lenp
, loff_t
*ppos
)
2290 #endif /* CONFIG_PROC_FS */
2294 * General sysctl support routines
2297 /* The generic string strategy routine: */
2298 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2299 void __user
*oldval
, size_t __user
*oldlenp
,
2300 void __user
*newval
, size_t newlen
, void **context
)
2302 if (!table
->data
|| !table
->maxlen
)
2305 if (oldval
&& oldlenp
) {
2307 if (get_user(bufsize
, oldlenp
))
2310 size_t len
= strlen(table
->data
), copied
;
2312 /* This shouldn't trigger for a well-formed sysctl */
2313 if (len
> table
->maxlen
)
2314 len
= table
->maxlen
;
2316 /* Copy up to a max of bufsize-1 bytes of the string */
2317 copied
= (len
>= bufsize
) ? bufsize
- 1 : len
;
2319 if (copy_to_user(oldval
, table
->data
, copied
) ||
2320 put_user(0, (char __user
*)(oldval
+ copied
)))
2322 if (put_user(len
, oldlenp
))
2326 if (newval
&& newlen
) {
2327 size_t len
= newlen
;
2328 if (len
> table
->maxlen
)
2329 len
= table
->maxlen
;
2330 if(copy_from_user(table
->data
, newval
, len
))
2332 if (len
== table
->maxlen
)
2334 ((char *) table
->data
)[len
] = 0;
2340 * This function makes sure that all of the integers in the vector
2341 * are between the minimum and maximum values given in the arrays
2342 * table->extra1 and table->extra2, respectively.
2344 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2345 void __user
*oldval
, size_t __user
*oldlenp
,
2346 void __user
*newval
, size_t newlen
, void **context
)
2349 if (newval
&& newlen
) {
2350 int __user
*vec
= (int __user
*) newval
;
2351 int *min
= (int *) table
->extra1
;
2352 int *max
= (int *) table
->extra2
;
2356 if (newlen
% sizeof(int) != 0)
2359 if (!table
->extra1
&& !table
->extra2
)
2362 if (newlen
> table
->maxlen
)
2363 newlen
= table
->maxlen
;
2364 length
= newlen
/ sizeof(int);
2366 for (i
= 0; i
< length
; i
++) {
2368 if (get_user(value
, vec
+ i
))
2370 if (min
&& value
< min
[i
])
2372 if (max
&& value
> max
[i
])
2379 /* Strategy function to convert jiffies to seconds */
2380 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2381 void __user
*oldval
, size_t __user
*oldlenp
,
2382 void __user
*newval
, size_t newlen
, void **context
)
2387 if (get_user(olen
, oldlenp
))
2389 if (olen
!=sizeof(int))
2392 if (put_user(*(int *)(table
->data
)/HZ
, (int __user
*)oldval
) ||
2393 (oldlenp
&& put_user(sizeof(int),oldlenp
)))
2396 if (newval
&& newlen
) {
2398 if (newlen
!= sizeof(int))
2400 if (get_user(new, (int __user
*)newval
))
2402 *(int *)(table
->data
) = new*HZ
;
2407 /* Strategy function to convert jiffies to seconds */
2408 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2409 void __user
*oldval
, size_t __user
*oldlenp
,
2410 void __user
*newval
, size_t newlen
, void **context
)
2415 if (get_user(olen
, oldlenp
))
2417 if (olen
!=sizeof(int))
2420 if (put_user(jiffies_to_msecs(*(int *)(table
->data
)), (int __user
*)oldval
) ||
2421 (oldlenp
&& put_user(sizeof(int),oldlenp
)))
2424 if (newval
&& newlen
) {
2426 if (newlen
!= sizeof(int))
2428 if (get_user(new, (int __user
*)newval
))
2430 *(int *)(table
->data
) = msecs_to_jiffies(new);
2435 #else /* CONFIG_SYSCTL */
2438 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
2443 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2444 void __user
*oldval
, size_t __user
*oldlenp
,
2445 void __user
*newval
, size_t newlen
, void **context
)
2450 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2451 void __user
*oldval
, size_t __user
*oldlenp
,
2452 void __user
*newval
, size_t newlen
, void **context
)
2457 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2458 void __user
*oldval
, size_t __user
*oldlenp
,
2459 void __user
*newval
, size_t newlen
, void **context
)
2464 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2465 void __user
*oldval
, size_t __user
*oldlenp
,
2466 void __user
*newval
, size_t newlen
, void **context
)
2471 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
2472 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2477 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
2478 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2483 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
2484 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2489 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2490 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2495 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2496 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2501 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2502 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2507 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2508 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2513 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2514 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2519 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2521 void __user
*buffer
,
2522 size_t *lenp
, loff_t
*ppos
)
2527 struct ctl_table_header
* register_sysctl_table(ctl_table
* table
,
2533 void unregister_sysctl_table(struct ctl_table_header
* table
)
2537 #endif /* CONFIG_SYSCTL */
2540 * No sense putting this after each symbol definition, twice,
2541 * exception granted :-)
2543 EXPORT_SYMBOL(proc_dointvec
);
2544 EXPORT_SYMBOL(proc_dointvec_jiffies
);
2545 EXPORT_SYMBOL(proc_dointvec_minmax
);
2546 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
2547 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
2548 EXPORT_SYMBOL(proc_dostring
);
2549 EXPORT_SYMBOL(proc_doulongvec_minmax
);
2550 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);
2551 EXPORT_SYMBOL(register_sysctl_table
);
2552 EXPORT_SYMBOL(sysctl_intvec
);
2553 EXPORT_SYMBOL(sysctl_jiffies
);
2554 EXPORT_SYMBOL(sysctl_ms_jiffies
);
2555 EXPORT_SYMBOL(sysctl_string
);
2556 EXPORT_SYMBOL(unregister_sysctl_table
);