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 extern int proc_nr_files(ctl_table *table, int write, struct file *filp,
54 void __user *buffer, size_t *lenp, loff_t *ppos);
56 #if defined(CONFIG_SYSCTL)
58 /* External variables not in a header file. */
60 extern int sysctl_overcommit_memory;
61 extern int sysctl_overcommit_ratio;
62 extern int sysctl_panic_on_oom;
63 extern int max_threads;
64 extern int sysrq_enabled;
65 extern int core_uses_pid;
66 extern int suid_dumpable;
67 extern char core_pattern[];
70 extern int min_free_kbytes;
71 extern int printk_ratelimit_jiffies;
72 extern int printk_ratelimit_burst;
73 extern int pid_max_min, pid_max_max;
74 extern int sysctl_drop_caches;
75 extern int percpu_pagelist_fraction;
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 static int parse_table(int __user *, int, void __user *, size_t __user *, void __user *, size_t,
136 ctl_table *, void **);
137 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
138 void __user *buffer, size_t *lenp, loff_t *ppos);
140 static ctl_table root_table[];
141 static struct ctl_table_header root_table_header =
142 { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
144 static ctl_table kern_table[];
145 static ctl_table vm_table[];
146 static ctl_table proc_table[];
147 static ctl_table fs_table[];
148 static ctl_table debug_table[];
149 static ctl_table dev_table[];
150 extern ctl_table random_table[];
151 #ifdef CONFIG_UNIX98_PTYS
152 extern ctl_table pty_table[];
154 #ifdef CONFIG_INOTIFY_USER
155 extern ctl_table inotify_table[];
158 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
159 int sysctl_legacy_va_layout;
162 /* /proc declarations: */
164 #ifdef CONFIG_PROC_FS
166 static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
167 static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
168 static int proc_opensys(struct inode *, struct file *);
170 struct file_operations proc_sys_file_operations = {
171 .open = proc_opensys,
172 .read = proc_readsys,
173 .write = proc_writesys,
176 extern struct proc_dir_entry *proc_sys_root;
178 static void register_proc_table(ctl_table *, struct proc_dir_entry *, void *);
179 static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
182 /* The default sysctl tables: */
184 static ctl_table root_table[] = {
186 .ctl_name = CTL_KERN,
187 .procname = "kernel",
206 .ctl_name = CTL_PROC,
218 .ctl_name = CTL_DEBUG,
221 .child = debug_table,
233 static ctl_table kern_table[] = {
235 .ctl_name = KERN_OSTYPE,
236 .procname = "ostype",
237 .data = system_utsname.sysname,
238 .maxlen = sizeof(system_utsname.sysname),
240 .proc_handler = &proc_doutsstring,
241 .strategy = &sysctl_string,
244 .ctl_name = KERN_OSRELEASE,
245 .procname = "osrelease",
246 .data = system_utsname.release,
247 .maxlen = sizeof(system_utsname.release),
249 .proc_handler = &proc_doutsstring,
250 .strategy = &sysctl_string,
253 .ctl_name = KERN_VERSION,
254 .procname = "version",
255 .data = system_utsname.version,
256 .maxlen = sizeof(system_utsname.version),
258 .proc_handler = &proc_doutsstring,
259 .strategy = &sysctl_string,
262 .ctl_name = KERN_NODENAME,
263 .procname = "hostname",
264 .data = system_utsname.nodename,
265 .maxlen = sizeof(system_utsname.nodename),
267 .proc_handler = &proc_doutsstring,
268 .strategy = &sysctl_string,
271 .ctl_name = KERN_DOMAINNAME,
272 .procname = "domainname",
273 .data = system_utsname.domainname,
274 .maxlen = sizeof(system_utsname.domainname),
276 .proc_handler = &proc_doutsstring,
277 .strategy = &sysctl_string,
280 .ctl_name = KERN_PANIC,
282 .data = &panic_timeout,
283 .maxlen = sizeof(int),
285 .proc_handler = &proc_dointvec,
288 .ctl_name = KERN_CORE_USES_PID,
289 .procname = "core_uses_pid",
290 .data = &core_uses_pid,
291 .maxlen = sizeof(int),
293 .proc_handler = &proc_dointvec,
296 .ctl_name = KERN_CORE_PATTERN,
297 .procname = "core_pattern",
298 .data = core_pattern,
301 .proc_handler = &proc_dostring,
302 .strategy = &sysctl_string,
305 .ctl_name = KERN_TAINTED,
306 .procname = "tainted",
308 .maxlen = sizeof(int),
310 .proc_handler = &proc_dointvec,
313 .ctl_name = KERN_CAP_BSET,
314 .procname = "cap-bound",
316 .maxlen = sizeof(kernel_cap_t),
318 .proc_handler = &proc_dointvec_bset,
320 #ifdef CONFIG_BLK_DEV_INITRD
322 .ctl_name = KERN_REALROOTDEV,
323 .procname = "real-root-dev",
324 .data = &real_root_dev,
325 .maxlen = sizeof(int),
327 .proc_handler = &proc_dointvec,
332 .ctl_name = KERN_SPARC_REBOOT,
333 .procname = "reboot-cmd",
334 .data = reboot_command,
337 .proc_handler = &proc_dostring,
338 .strategy = &sysctl_string,
341 .ctl_name = KERN_SPARC_STOP_A,
342 .procname = "stop-a",
343 .data = &stop_a_enabled,
344 .maxlen = sizeof (int),
346 .proc_handler = &proc_dointvec,
349 .ctl_name = KERN_SPARC_SCONS_PWROFF,
350 .procname = "scons-poweroff",
351 .data = &scons_pwroff,
352 .maxlen = sizeof (int),
354 .proc_handler = &proc_dointvec,
359 .ctl_name = KERN_HPPA_PWRSW,
360 .procname = "soft-power",
361 .data = &pwrsw_enabled,
362 .maxlen = sizeof (int),
364 .proc_handler = &proc_dointvec,
367 .ctl_name = KERN_HPPA_UNALIGNED,
368 .procname = "unaligned-trap",
369 .data = &unaligned_enabled,
370 .maxlen = sizeof (int),
372 .proc_handler = &proc_dointvec,
376 .ctl_name = KERN_CTLALTDEL,
377 .procname = "ctrl-alt-del",
379 .maxlen = sizeof(int),
381 .proc_handler = &proc_dointvec,
384 .ctl_name = KERN_PRINTK,
385 .procname = "printk",
386 .data = &console_loglevel,
387 .maxlen = 4*sizeof(int),
389 .proc_handler = &proc_dointvec,
393 .ctl_name = KERN_MODPROBE,
394 .procname = "modprobe",
395 .data = &modprobe_path,
396 .maxlen = KMOD_PATH_LEN,
398 .proc_handler = &proc_dostring,
399 .strategy = &sysctl_string,
402 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
404 .ctl_name = KERN_HOTPLUG,
405 .procname = "hotplug",
406 .data = &uevent_helper,
407 .maxlen = UEVENT_HELPER_PATH_LEN,
409 .proc_handler = &proc_dostring,
410 .strategy = &sysctl_string,
413 #ifdef CONFIG_CHR_DEV_SG
415 .ctl_name = KERN_SG_BIG_BUFF,
416 .procname = "sg-big-buff",
417 .data = &sg_big_buff,
418 .maxlen = sizeof (int),
420 .proc_handler = &proc_dointvec,
423 #ifdef CONFIG_BSD_PROCESS_ACCT
425 .ctl_name = KERN_ACCT,
428 .maxlen = 3*sizeof(int),
430 .proc_handler = &proc_dointvec,
433 #ifdef CONFIG_SYSVIPC
435 .ctl_name = KERN_SHMMAX,
436 .procname = "shmmax",
438 .maxlen = sizeof (size_t),
440 .proc_handler = &proc_doulongvec_minmax,
443 .ctl_name = KERN_SHMALL,
444 .procname = "shmall",
446 .maxlen = sizeof (size_t),
448 .proc_handler = &proc_doulongvec_minmax,
451 .ctl_name = KERN_SHMMNI,
452 .procname = "shmmni",
454 .maxlen = sizeof (int),
456 .proc_handler = &proc_dointvec,
459 .ctl_name = KERN_MSGMAX,
460 .procname = "msgmax",
462 .maxlen = sizeof (int),
464 .proc_handler = &proc_dointvec,
467 .ctl_name = KERN_MSGMNI,
468 .procname = "msgmni",
470 .maxlen = sizeof (int),
472 .proc_handler = &proc_dointvec,
475 .ctl_name = KERN_MSGMNB,
476 .procname = "msgmnb",
478 .maxlen = sizeof (int),
480 .proc_handler = &proc_dointvec,
483 .ctl_name = KERN_SEM,
486 .maxlen = 4*sizeof (int),
488 .proc_handler = &proc_dointvec,
491 #ifdef CONFIG_MAGIC_SYSRQ
493 .ctl_name = KERN_SYSRQ,
495 .data = &sysrq_enabled,
496 .maxlen = sizeof (int),
498 .proc_handler = &proc_dointvec,
502 .ctl_name = KERN_CADPID,
503 .procname = "cad_pid",
505 .maxlen = sizeof (int),
507 .proc_handler = &proc_dointvec,
510 .ctl_name = KERN_MAX_THREADS,
511 .procname = "threads-max",
512 .data = &max_threads,
513 .maxlen = sizeof(int),
515 .proc_handler = &proc_dointvec,
518 .ctl_name = KERN_RANDOM,
519 .procname = "random",
521 .child = random_table,
523 #ifdef CONFIG_UNIX98_PTYS
525 .ctl_name = KERN_PTY,
532 .ctl_name = KERN_OVERFLOWUID,
533 .procname = "overflowuid",
534 .data = &overflowuid,
535 .maxlen = sizeof(int),
537 .proc_handler = &proc_dointvec_minmax,
538 .strategy = &sysctl_intvec,
539 .extra1 = &minolduid,
540 .extra2 = &maxolduid,
543 .ctl_name = KERN_OVERFLOWGID,
544 .procname = "overflowgid",
545 .data = &overflowgid,
546 .maxlen = sizeof(int),
548 .proc_handler = &proc_dointvec_minmax,
549 .strategy = &sysctl_intvec,
550 .extra1 = &minolduid,
551 .extra2 = &maxolduid,
554 #ifdef CONFIG_MATHEMU
556 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
557 .procname = "ieee_emulation_warnings",
558 .data = &sysctl_ieee_emulation_warnings,
559 .maxlen = sizeof(int),
561 .proc_handler = &proc_dointvec,
564 #ifdef CONFIG_NO_IDLE_HZ
566 .ctl_name = KERN_HZ_TIMER,
567 .procname = "hz_timer",
568 .data = &sysctl_hz_timer,
569 .maxlen = sizeof(int),
571 .proc_handler = &proc_dointvec,
575 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
576 .procname = "userprocess_debug",
577 .data = &sysctl_userprocess_debug,
578 .maxlen = sizeof(int),
580 .proc_handler = &proc_dointvec,
584 .ctl_name = KERN_PIDMAX,
585 .procname = "pid_max",
587 .maxlen = sizeof (int),
589 .proc_handler = &proc_dointvec_minmax,
590 .strategy = sysctl_intvec,
591 .extra1 = &pid_max_min,
592 .extra2 = &pid_max_max,
595 .ctl_name = KERN_PANIC_ON_OOPS,
596 .procname = "panic_on_oops",
597 .data = &panic_on_oops,
598 .maxlen = sizeof(int),
600 .proc_handler = &proc_dointvec,
603 .ctl_name = KERN_PRINTK_RATELIMIT,
604 .procname = "printk_ratelimit",
605 .data = &printk_ratelimit_jiffies,
606 .maxlen = sizeof(int),
608 .proc_handler = &proc_dointvec_jiffies,
609 .strategy = &sysctl_jiffies,
612 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
613 .procname = "printk_ratelimit_burst",
614 .data = &printk_ratelimit_burst,
615 .maxlen = sizeof(int),
617 .proc_handler = &proc_dointvec,
620 .ctl_name = KERN_NGROUPS_MAX,
621 .procname = "ngroups_max",
622 .data = &ngroups_max,
623 .maxlen = sizeof (int),
625 .proc_handler = &proc_dointvec,
627 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
629 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
630 .procname = "unknown_nmi_panic",
631 .data = &unknown_nmi_panic,
632 .maxlen = sizeof (int),
634 .proc_handler = &proc_unknown_nmi_panic,
637 #if defined(CONFIG_X86)
639 .ctl_name = KERN_BOOTLOADER_TYPE,
640 .procname = "bootloader_type",
641 .data = &bootloader_type,
642 .maxlen = sizeof (int),
644 .proc_handler = &proc_dointvec,
647 #if defined(CONFIG_MMU)
649 .ctl_name = KERN_RANDOMIZE,
650 .procname = "randomize_va_space",
651 .data = &randomize_va_space,
652 .maxlen = sizeof(int),
654 .proc_handler = &proc_dointvec,
657 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
659 .ctl_name = KERN_SPIN_RETRY,
660 .procname = "spin_retry",
662 .maxlen = sizeof (int),
664 .proc_handler = &proc_dointvec,
667 #ifdef CONFIG_ACPI_SLEEP
669 .ctl_name = KERN_ACPI_VIDEO_FLAGS,
670 .procname = "acpi_video_flags",
671 .data = &acpi_video_flags,
672 .maxlen = sizeof (unsigned long),
674 .proc_handler = &proc_doulongvec_minmax,
679 .ctl_name = KERN_IA64_UNALIGNED,
680 .procname = "ignore-unaligned-usertrap",
681 .data = &no_unaligned_warning,
682 .maxlen = sizeof (int),
684 .proc_handler = &proc_dointvec,
690 /* Constants for minimum and maximum testing in vm_table.
691 We use these as one-element integer vectors. */
693 static int one_hundred = 100;
696 static ctl_table vm_table[] = {
698 .ctl_name = VM_OVERCOMMIT_MEMORY,
699 .procname = "overcommit_memory",
700 .data = &sysctl_overcommit_memory,
701 .maxlen = sizeof(sysctl_overcommit_memory),
703 .proc_handler = &proc_dointvec,
706 .ctl_name = VM_PANIC_ON_OOM,
707 .procname = "panic_on_oom",
708 .data = &sysctl_panic_on_oom,
709 .maxlen = sizeof(sysctl_panic_on_oom),
711 .proc_handler = &proc_dointvec,
714 .ctl_name = VM_OVERCOMMIT_RATIO,
715 .procname = "overcommit_ratio",
716 .data = &sysctl_overcommit_ratio,
717 .maxlen = sizeof(sysctl_overcommit_ratio),
719 .proc_handler = &proc_dointvec,
722 .ctl_name = VM_PAGE_CLUSTER,
723 .procname = "page-cluster",
724 .data = &page_cluster,
725 .maxlen = sizeof(int),
727 .proc_handler = &proc_dointvec,
730 .ctl_name = VM_DIRTY_BACKGROUND,
731 .procname = "dirty_background_ratio",
732 .data = &dirty_background_ratio,
733 .maxlen = sizeof(dirty_background_ratio),
735 .proc_handler = &proc_dointvec_minmax,
736 .strategy = &sysctl_intvec,
738 .extra2 = &one_hundred,
741 .ctl_name = VM_DIRTY_RATIO,
742 .procname = "dirty_ratio",
743 .data = &vm_dirty_ratio,
744 .maxlen = sizeof(vm_dirty_ratio),
746 .proc_handler = &proc_dointvec_minmax,
747 .strategy = &sysctl_intvec,
749 .extra2 = &one_hundred,
752 .ctl_name = VM_DIRTY_WB_CS,
753 .procname = "dirty_writeback_centisecs",
754 .data = &dirty_writeback_interval,
755 .maxlen = sizeof(dirty_writeback_interval),
757 .proc_handler = &dirty_writeback_centisecs_handler,
760 .ctl_name = VM_DIRTY_EXPIRE_CS,
761 .procname = "dirty_expire_centisecs",
762 .data = &dirty_expire_interval,
763 .maxlen = sizeof(dirty_expire_interval),
765 .proc_handler = &proc_dointvec_userhz_jiffies,
768 .ctl_name = VM_NR_PDFLUSH_THREADS,
769 .procname = "nr_pdflush_threads",
770 .data = &nr_pdflush_threads,
771 .maxlen = sizeof nr_pdflush_threads,
772 .mode = 0444 /* read-only*/,
773 .proc_handler = &proc_dointvec,
776 .ctl_name = VM_SWAPPINESS,
777 .procname = "swappiness",
778 .data = &vm_swappiness,
779 .maxlen = sizeof(vm_swappiness),
781 .proc_handler = &proc_dointvec_minmax,
782 .strategy = &sysctl_intvec,
784 .extra2 = &one_hundred,
786 #ifdef CONFIG_HUGETLB_PAGE
788 .ctl_name = VM_HUGETLB_PAGES,
789 .procname = "nr_hugepages",
790 .data = &max_huge_pages,
791 .maxlen = sizeof(unsigned long),
793 .proc_handler = &hugetlb_sysctl_handler,
794 .extra1 = (void *)&hugetlb_zero,
795 .extra2 = (void *)&hugetlb_infinity,
798 .ctl_name = VM_HUGETLB_GROUP,
799 .procname = "hugetlb_shm_group",
800 .data = &sysctl_hugetlb_shm_group,
801 .maxlen = sizeof(gid_t),
803 .proc_handler = &proc_dointvec,
807 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
808 .procname = "lowmem_reserve_ratio",
809 .data = &sysctl_lowmem_reserve_ratio,
810 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
812 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
813 .strategy = &sysctl_intvec,
816 .ctl_name = VM_DROP_PAGECACHE,
817 .procname = "drop_caches",
818 .data = &sysctl_drop_caches,
819 .maxlen = sizeof(int),
821 .proc_handler = drop_caches_sysctl_handler,
822 .strategy = &sysctl_intvec,
825 .ctl_name = VM_MIN_FREE_KBYTES,
826 .procname = "min_free_kbytes",
827 .data = &min_free_kbytes,
828 .maxlen = sizeof(min_free_kbytes),
830 .proc_handler = &min_free_kbytes_sysctl_handler,
831 .strategy = &sysctl_intvec,
835 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
836 .procname = "percpu_pagelist_fraction",
837 .data = &percpu_pagelist_fraction,
838 .maxlen = sizeof(percpu_pagelist_fraction),
840 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
841 .strategy = &sysctl_intvec,
842 .extra1 = &min_percpu_pagelist_fract,
846 .ctl_name = VM_MAX_MAP_COUNT,
847 .procname = "max_map_count",
848 .data = &sysctl_max_map_count,
849 .maxlen = sizeof(sysctl_max_map_count),
851 .proc_handler = &proc_dointvec
855 .ctl_name = VM_LAPTOP_MODE,
856 .procname = "laptop_mode",
857 .data = &laptop_mode,
858 .maxlen = sizeof(laptop_mode),
860 .proc_handler = &proc_dointvec_jiffies,
861 .strategy = &sysctl_jiffies,
864 .ctl_name = VM_BLOCK_DUMP,
865 .procname = "block_dump",
867 .maxlen = sizeof(block_dump),
869 .proc_handler = &proc_dointvec,
870 .strategy = &sysctl_intvec,
874 .ctl_name = VM_VFS_CACHE_PRESSURE,
875 .procname = "vfs_cache_pressure",
876 .data = &sysctl_vfs_cache_pressure,
877 .maxlen = sizeof(sysctl_vfs_cache_pressure),
879 .proc_handler = &proc_dointvec,
880 .strategy = &sysctl_intvec,
883 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
885 .ctl_name = VM_LEGACY_VA_LAYOUT,
886 .procname = "legacy_va_layout",
887 .data = &sysctl_legacy_va_layout,
888 .maxlen = sizeof(sysctl_legacy_va_layout),
890 .proc_handler = &proc_dointvec,
891 .strategy = &sysctl_intvec,
897 .ctl_name = VM_SWAP_TOKEN_TIMEOUT,
898 .procname = "swap_token_timeout",
899 .data = &swap_token_default_timeout,
900 .maxlen = sizeof(swap_token_default_timeout),
902 .proc_handler = &proc_dointvec_jiffies,
903 .strategy = &sysctl_jiffies,
908 .ctl_name = VM_ZONE_RECLAIM_MODE,
909 .procname = "zone_reclaim_mode",
910 .data = &zone_reclaim_mode,
911 .maxlen = sizeof(zone_reclaim_mode),
913 .proc_handler = &proc_dointvec,
914 .strategy = &sysctl_intvec,
918 .ctl_name = VM_ZONE_RECLAIM_INTERVAL,
919 .procname = "zone_reclaim_interval",
920 .data = &zone_reclaim_interval,
921 .maxlen = sizeof(zone_reclaim_interval),
923 .proc_handler = &proc_dointvec_jiffies,
924 .strategy = &sysctl_jiffies,
930 static ctl_table proc_table[] = {
934 static ctl_table fs_table[] = {
936 .ctl_name = FS_NRINODE,
937 .procname = "inode-nr",
938 .data = &inodes_stat,
939 .maxlen = 2*sizeof(int),
941 .proc_handler = &proc_dointvec,
944 .ctl_name = FS_STATINODE,
945 .procname = "inode-state",
946 .data = &inodes_stat,
947 .maxlen = 7*sizeof(int),
949 .proc_handler = &proc_dointvec,
952 .ctl_name = FS_NRFILE,
953 .procname = "file-nr",
955 .maxlen = 3*sizeof(int),
957 .proc_handler = &proc_nr_files,
960 .ctl_name = FS_MAXFILE,
961 .procname = "file-max",
962 .data = &files_stat.max_files,
963 .maxlen = sizeof(int),
965 .proc_handler = &proc_dointvec,
968 .ctl_name = FS_DENTRY,
969 .procname = "dentry-state",
970 .data = &dentry_stat,
971 .maxlen = 6*sizeof(int),
973 .proc_handler = &proc_dointvec,
976 .ctl_name = FS_OVERFLOWUID,
977 .procname = "overflowuid",
978 .data = &fs_overflowuid,
979 .maxlen = sizeof(int),
981 .proc_handler = &proc_dointvec_minmax,
982 .strategy = &sysctl_intvec,
983 .extra1 = &minolduid,
984 .extra2 = &maxolduid,
987 .ctl_name = FS_OVERFLOWGID,
988 .procname = "overflowgid",
989 .data = &fs_overflowgid,
990 .maxlen = sizeof(int),
992 .proc_handler = &proc_dointvec_minmax,
993 .strategy = &sysctl_intvec,
994 .extra1 = &minolduid,
995 .extra2 = &maxolduid,
998 .ctl_name = FS_LEASES,
999 .procname = "leases-enable",
1000 .data = &leases_enable,
1001 .maxlen = sizeof(int),
1003 .proc_handler = &proc_dointvec,
1005 #ifdef CONFIG_DNOTIFY
1007 .ctl_name = FS_DIR_NOTIFY,
1008 .procname = "dir-notify-enable",
1009 .data = &dir_notify_enable,
1010 .maxlen = sizeof(int),
1012 .proc_handler = &proc_dointvec,
1017 .ctl_name = FS_LEASE_TIME,
1018 .procname = "lease-break-time",
1019 .data = &lease_break_time,
1020 .maxlen = sizeof(int),
1022 .proc_handler = &proc_dointvec,
1025 .ctl_name = FS_AIO_NR,
1026 .procname = "aio-nr",
1028 .maxlen = sizeof(aio_nr),
1030 .proc_handler = &proc_doulongvec_minmax,
1033 .ctl_name = FS_AIO_MAX_NR,
1034 .procname = "aio-max-nr",
1035 .data = &aio_max_nr,
1036 .maxlen = sizeof(aio_max_nr),
1038 .proc_handler = &proc_doulongvec_minmax,
1040 #ifdef CONFIG_INOTIFY_USER
1042 .ctl_name = FS_INOTIFY,
1043 .procname = "inotify",
1045 .child = inotify_table,
1050 .ctl_name = KERN_SETUID_DUMPABLE,
1051 .procname = "suid_dumpable",
1052 .data = &suid_dumpable,
1053 .maxlen = sizeof(int),
1055 .proc_handler = &proc_dointvec,
1060 static ctl_table debug_table[] = {
1064 static ctl_table dev_table[] = {
1068 extern void init_irq_proc (void);
1070 static DEFINE_SPINLOCK(sysctl_lock);
1072 /* called under sysctl_lock */
1073 static int use_table(struct ctl_table_header *p)
1075 if (unlikely(p->unregistering))
1081 /* called under sysctl_lock */
1082 static void unuse_table(struct ctl_table_header *p)
1085 if (unlikely(p->unregistering))
1086 complete(p->unregistering);
1089 /* called under sysctl_lock, will reacquire if has to wait */
1090 static void start_unregistering(struct ctl_table_header *p)
1093 * if p->used is 0, nobody will ever touch that entry again;
1094 * we'll eliminate all paths to it before dropping sysctl_lock
1096 if (unlikely(p->used)) {
1097 struct completion wait;
1098 init_completion(&wait);
1099 p->unregistering = &wait;
1100 spin_unlock(&sysctl_lock);
1101 wait_for_completion(&wait);
1102 spin_lock(&sysctl_lock);
1105 * do not remove from the list until nobody holds it; walking the
1106 * list in do_sysctl() relies on that.
1108 list_del_init(&p->ctl_entry);
1111 void __init sysctl_init(void)
1113 #ifdef CONFIG_PROC_FS
1114 register_proc_table(root_table, proc_sys_root, &root_table_header);
1119 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1120 void __user *newval, size_t newlen)
1122 struct list_head *tmp;
1123 int error = -ENOTDIR;
1125 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1129 if (!oldlenp || get_user(old_len, oldlenp))
1132 spin_lock(&sysctl_lock);
1133 tmp = &root_table_header.ctl_entry;
1135 struct ctl_table_header *head =
1136 list_entry(tmp, struct ctl_table_header, ctl_entry);
1137 void *context = NULL;
1139 if (!use_table(head))
1142 spin_unlock(&sysctl_lock);
1144 error = parse_table(name, nlen, oldval, oldlenp,
1145 newval, newlen, head->ctl_table,
1149 spin_lock(&sysctl_lock);
1151 if (error != -ENOTDIR)
1153 } while ((tmp = tmp->next) != &root_table_header.ctl_entry);
1154 spin_unlock(&sysctl_lock);
1158 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1160 struct __sysctl_args tmp;
1163 if (copy_from_user(&tmp, args, sizeof(tmp)))
1167 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1168 tmp.newval, tmp.newlen);
1174 * ctl_perm does NOT grant the superuser all rights automatically, because
1175 * some sysctl variables are readonly even to root.
1178 static int test_perm(int mode, int op)
1182 else if (in_egroup_p(0))
1184 if ((mode & op & 0007) == op)
1189 static inline int ctl_perm(ctl_table *table, int op)
1192 error = security_sysctl(table, op);
1195 return test_perm(table->mode, op);
1198 static int parse_table(int __user *name, int nlen,
1199 void __user *oldval, size_t __user *oldlenp,
1200 void __user *newval, size_t newlen,
1201 ctl_table *table, void **context)
1207 if (get_user(n, name))
1209 for ( ; table->ctl_name; table++) {
1210 if (n == table->ctl_name || table->ctl_name == CTL_ANY) {
1213 if (ctl_perm(table, 001))
1215 if (table->strategy) {
1216 error = table->strategy(
1219 newval, newlen, context);
1225 table = table->child;
1228 error = do_sysctl_strategy(table, name, nlen,
1230 newval, newlen, context);
1237 /* Perform the actual read/write of a sysctl table entry. */
1238 int do_sysctl_strategy (ctl_table *table,
1239 int __user *name, int nlen,
1240 void __user *oldval, size_t __user *oldlenp,
1241 void __user *newval, size_t newlen, void **context)
1250 if (ctl_perm(table, op))
1253 if (table->strategy) {
1254 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1255 newval, newlen, context);
1262 /* If there is no strategy routine, or if the strategy returns
1263 * zero, proceed with automatic r/w */
1264 if (table->data && table->maxlen) {
1265 if (oldval && oldlenp) {
1266 if (get_user(len, oldlenp))
1269 if (len > table->maxlen)
1270 len = table->maxlen;
1271 if(copy_to_user(oldval, table->data, len))
1273 if(put_user(len, oldlenp))
1277 if (newval && newlen) {
1279 if (len > table->maxlen)
1280 len = table->maxlen;
1281 if(copy_from_user(table->data, newval, len))
1289 * register_sysctl_table - register a sysctl hierarchy
1290 * @table: the top-level table structure
1291 * @insert_at_head: whether the entry should be inserted in front or at the end
1293 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1294 * array. An entry with a ctl_name of 0 terminates the table.
1296 * The members of the &ctl_table structure are used as follows:
1298 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1299 * must be unique within that level of sysctl
1301 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1302 * enter a sysctl file
1304 * data - a pointer to data for use by proc_handler
1306 * maxlen - the maximum size in bytes of the data
1308 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1310 * child - a pointer to the child sysctl table if this entry is a directory, or
1313 * proc_handler - the text handler routine (described below)
1315 * strategy - the strategy routine (described below)
1317 * de - for internal use by the sysctl routines
1319 * extra1, extra2 - extra pointers usable by the proc handler routines
1321 * Leaf nodes in the sysctl tree will be represented by a single file
1322 * under /proc; non-leaf nodes will be represented by directories.
1324 * sysctl(2) can automatically manage read and write requests through
1325 * the sysctl table. The data and maxlen fields of the ctl_table
1326 * struct enable minimal validation of the values being written to be
1327 * performed, and the mode field allows minimal authentication.
1329 * More sophisticated management can be enabled by the provision of a
1330 * strategy routine with the table entry. This will be called before
1331 * any automatic read or write of the data is performed.
1333 * The strategy routine may return
1335 * < 0 - Error occurred (error is passed to user process)
1337 * 0 - OK - proceed with automatic read or write.
1339 * > 0 - OK - read or write has been done by the strategy routine, so
1340 * return immediately.
1342 * There must be a proc_handler routine for any terminal nodes
1343 * mirrored under /proc/sys (non-terminals are handled by a built-in
1344 * directory handler). Several default handlers are available to
1345 * cover common cases -
1347 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1348 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1349 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1351 * It is the handler's job to read the input buffer from user memory
1352 * and process it. The handler should return 0 on success.
1354 * This routine returns %NULL on a failure to register, and a pointer
1355 * to the table header on success.
1357 struct ctl_table_header *register_sysctl_table(ctl_table * table,
1360 struct ctl_table_header *tmp;
1361 tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1364 tmp->ctl_table = table;
1365 INIT_LIST_HEAD(&tmp->ctl_entry);
1367 tmp->unregistering = NULL;
1368 spin_lock(&sysctl_lock);
1370 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
1372 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1373 spin_unlock(&sysctl_lock);
1374 #ifdef CONFIG_PROC_FS
1375 register_proc_table(table, proc_sys_root, tmp);
1381 * unregister_sysctl_table - unregister a sysctl table hierarchy
1382 * @header: the header returned from register_sysctl_table
1384 * Unregisters the sysctl table and all children. proc entries may not
1385 * actually be removed until they are no longer used by anyone.
1387 void unregister_sysctl_table(struct ctl_table_header * header)
1390 spin_lock(&sysctl_lock);
1391 start_unregistering(header);
1392 #ifdef CONFIG_PROC_FS
1393 unregister_proc_table(header->ctl_table, proc_sys_root);
1395 spin_unlock(&sysctl_lock);
1403 #ifdef CONFIG_PROC_FS
1405 /* Scan the sysctl entries in table and add them all into /proc */
1406 static void register_proc_table(ctl_table * table, struct proc_dir_entry *root, void *set)
1408 struct proc_dir_entry *de;
1412 for (; table->ctl_name; table++) {
1413 /* Can't do anything without a proc name. */
1414 if (!table->procname)
1416 /* Maybe we can't do anything with it... */
1417 if (!table->proc_handler && !table->child) {
1418 printk(KERN_WARNING "SYSCTL: Can't register %s\n",
1423 len = strlen(table->procname);
1427 if (table->proc_handler)
1431 for (de = root->subdir; de; de = de->next) {
1432 if (proc_match(len, table->procname, de))
1435 /* If the subdir exists already, de is non-NULL */
1439 de = create_proc_entry(table->procname, mode, root);
1443 de->data = (void *) table;
1444 if (table->proc_handler)
1445 de->proc_fops = &proc_sys_file_operations;
1448 if (de->mode & S_IFDIR)
1449 register_proc_table(table->child, de, set);
1454 * Unregister a /proc sysctl table and any subdirectories.
1456 static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
1458 struct proc_dir_entry *de;
1459 for (; table->ctl_name; table++) {
1460 if (!(de = table->de))
1462 if (de->mode & S_IFDIR) {
1463 if (!table->child) {
1464 printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
1467 unregister_proc_table(table->child, de);
1469 /* Don't unregister directories which still have entries.. */
1475 * In any case, mark the entry as goner; we'll keep it
1476 * around if it's busy, but we'll know to do nothing with
1477 * its fields. We are under sysctl_lock here.
1481 /* Don't unregister proc entries that are still being used.. */
1482 if (atomic_read(&de->count))
1486 remove_proc_entry(table->procname, root);
1490 static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
1491 size_t count, loff_t *ppos)
1494 struct proc_dir_entry *de = PDE(file->f_dentry->d_inode);
1495 struct ctl_table *table;
1497 ssize_t error = -ENOTDIR;
1499 spin_lock(&sysctl_lock);
1500 if (de && de->data && use_table(de->set)) {
1502 * at that point we know that sysctl was not unregistered
1503 * and won't be until we finish
1505 spin_unlock(&sysctl_lock);
1506 table = (struct ctl_table *) de->data;
1507 if (!table || !table->proc_handler)
1510 op = (write ? 002 : 004);
1511 if (ctl_perm(table, op))
1514 /* careful: calling conventions are nasty here */
1516 error = (*table->proc_handler)(table, write, file,
1521 spin_lock(&sysctl_lock);
1522 unuse_table(de->set);
1524 spin_unlock(&sysctl_lock);
1528 static int proc_opensys(struct inode *inode, struct file *file)
1530 if (file->f_mode & FMODE_WRITE) {
1532 * sysctl entries that are not writable,
1533 * are _NOT_ writable, capabilities or not.
1535 if (!(inode->i_mode & S_IWUSR))
1542 static ssize_t proc_readsys(struct file * file, char __user * buf,
1543 size_t count, loff_t *ppos)
1545 return do_rw_proc(0, file, buf, count, ppos);
1548 static ssize_t proc_writesys(struct file * file, const char __user * buf,
1549 size_t count, loff_t *ppos)
1551 return do_rw_proc(1, file, (char __user *) buf, count, ppos);
1555 * proc_dostring - read a string sysctl
1556 * @table: the sysctl table
1557 * @write: %TRUE if this is a write to the sysctl file
1558 * @filp: the file structure
1559 * @buffer: the user buffer
1560 * @lenp: the size of the user buffer
1561 * @ppos: file position
1563 * Reads/writes a string from/to the user buffer. If the kernel
1564 * buffer provided is not large enough to hold the string, the
1565 * string is truncated. The copied string is %NULL-terminated.
1566 * If the string is being read by the user process, it is copied
1567 * and a newline '\n' is added. It is truncated if the buffer is
1570 * Returns 0 on success.
1572 int proc_dostring(ctl_table *table, int write, struct file *filp,
1573 void __user *buffer, size_t *lenp, loff_t *ppos)
1579 if (!table->data || !table->maxlen || !*lenp ||
1580 (*ppos && !write)) {
1588 while (len < *lenp) {
1589 if (get_user(c, p++))
1591 if (c == 0 || c == '\n')
1595 if (len >= table->maxlen)
1596 len = table->maxlen-1;
1597 if(copy_from_user(table->data, buffer, len))
1599 ((char *) table->data)[len] = 0;
1602 len = strlen(table->data);
1603 if (len > table->maxlen)
1604 len = table->maxlen;
1608 if(copy_to_user(buffer, table->data, len))
1611 if(put_user('\n', ((char __user *) buffer) + len))
1622 * Special case of dostring for the UTS structure. This has locks
1623 * to observe. Should this be in kernel/sys.c ????
1626 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
1627 void __user *buffer, size_t *lenp, loff_t *ppos)
1632 down_read(&uts_sem);
1633 r=proc_dostring(table,0,filp,buffer,lenp, ppos);
1636 down_write(&uts_sem);
1637 r=proc_dostring(table,1,filp,buffer,lenp, ppos);
1643 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1645 int write, void *data)
1648 *valp = *negp ? -*lvalp : *lvalp;
1653 *lvalp = (unsigned long)-val;
1656 *lvalp = (unsigned long)val;
1662 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1663 void __user *buffer, size_t *lenp, loff_t *ppos,
1664 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1665 int write, void *data),
1668 #define TMPBUFLEN 21
1669 int *i, vleft, first=1, neg, val;
1673 char buf[TMPBUFLEN], *p;
1674 char __user *s = buffer;
1676 if (!table->data || !table->maxlen || !*lenp ||
1677 (*ppos && !write)) {
1682 i = (int *) table->data;
1683 vleft = table->maxlen / sizeof(*i);
1687 conv = do_proc_dointvec_conv;
1689 for (; left && vleft--; i++, first=0) {
1704 if (len > sizeof(buf) - 1)
1705 len = sizeof(buf) - 1;
1706 if (copy_from_user(buf, s, len))
1710 if (*p == '-' && left > 1) {
1714 if (*p < '0' || *p > '9')
1717 lval = simple_strtoul(p, &p, 0);
1720 if ((len < left) && *p && !isspace(*p))
1727 if (conv(&neg, &lval, i, 1, data))
1734 if (conv(&neg, &lval, i, 0, data))
1737 sprintf(p, "%s%lu", neg ? "-" : "", lval);
1741 if(copy_to_user(s, buf, len))
1748 if (!write && !first && left) {
1749 if(put_user('\n', s))
1756 if (get_user(c, s++))
1772 * proc_dointvec - read a vector of integers
1773 * @table: the sysctl table
1774 * @write: %TRUE if this is a write to the sysctl file
1775 * @filp: the file structure
1776 * @buffer: the user buffer
1777 * @lenp: the size of the user buffer
1778 * @ppos: file position
1780 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1781 * values from/to the user buffer, treated as an ASCII string.
1783 * Returns 0 on success.
1785 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1786 void __user *buffer, size_t *lenp, loff_t *ppos)
1788 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1798 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1800 int write, void *data)
1802 int op = *(int *)data;
1804 int val = *negp ? -*lvalp : *lvalp;
1806 case OP_SET: *valp = val; break;
1807 case OP_AND: *valp &= val; break;
1808 case OP_OR: *valp |= val; break;
1809 case OP_MAX: if(*valp < val)
1812 case OP_MIN: if(*valp > val)
1820 *lvalp = (unsigned long)-val;
1823 *lvalp = (unsigned long)val;
1830 * init may raise the set.
1833 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1834 void __user *buffer, size_t *lenp, loff_t *ppos)
1838 if (!capable(CAP_SYS_MODULE)) {
1842 op = (current->pid == 1) ? OP_SET : OP_AND;
1843 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1844 do_proc_dointvec_bset_conv,&op);
1847 struct do_proc_dointvec_minmax_conv_param {
1852 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1854 int write, void *data)
1856 struct do_proc_dointvec_minmax_conv_param *param = data;
1858 int val = *negp ? -*lvalp : *lvalp;
1859 if ((param->min && *param->min > val) ||
1860 (param->max && *param->max < val))
1867 *lvalp = (unsigned long)-val;
1870 *lvalp = (unsigned long)val;
1877 * proc_dointvec_minmax - read a vector of integers with min/max values
1878 * @table: the sysctl table
1879 * @write: %TRUE if this is a write to the sysctl file
1880 * @filp: the file structure
1881 * @buffer: the user buffer
1882 * @lenp: the size of the user buffer
1883 * @ppos: file position
1885 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1886 * values from/to the user buffer, treated as an ASCII string.
1888 * This routine will ensure the values are within the range specified by
1889 * table->extra1 (min) and table->extra2 (max).
1891 * Returns 0 on success.
1893 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1894 void __user *buffer, size_t *lenp, loff_t *ppos)
1896 struct do_proc_dointvec_minmax_conv_param param = {
1897 .min = (int *) table->extra1,
1898 .max = (int *) table->extra2,
1900 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1901 do_proc_dointvec_minmax_conv, ¶m);
1904 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1906 void __user *buffer,
1907 size_t *lenp, loff_t *ppos,
1908 unsigned long convmul,
1909 unsigned long convdiv)
1911 #define TMPBUFLEN 21
1912 unsigned long *i, *min, *max, val;
1913 int vleft, first=1, neg;
1915 char buf[TMPBUFLEN], *p;
1916 char __user *s = buffer;
1918 if (!table->data || !table->maxlen || !*lenp ||
1919 (*ppos && !write)) {
1924 i = (unsigned long *) table->data;
1925 min = (unsigned long *) table->extra1;
1926 max = (unsigned long *) table->extra2;
1927 vleft = table->maxlen / sizeof(unsigned long);
1930 for (; left && vleft--; i++, min++, max++, first=0) {
1945 if (len > TMPBUFLEN-1)
1947 if (copy_from_user(buf, s, len))
1951 if (*p == '-' && left > 1) {
1955 if (*p < '0' || *p > '9')
1957 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1959 if ((len < left) && *p && !isspace(*p))
1968 if ((min && val < *min) || (max && val > *max))
1975 sprintf(p, "%lu", convdiv * (*i) / convmul);
1979 if(copy_to_user(s, buf, len))
1986 if (!write && !first && left) {
1987 if(put_user('\n', s))
1994 if (get_user(c, s++))
2010 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2011 * @table: the sysctl table
2012 * @write: %TRUE if this is a write to the sysctl file
2013 * @filp: the file structure
2014 * @buffer: the user buffer
2015 * @lenp: the size of the user buffer
2016 * @ppos: file position
2018 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2019 * values from/to the user buffer, treated as an ASCII string.
2021 * This routine will ensure the values are within the range specified by
2022 * table->extra1 (min) and table->extra2 (max).
2024 * Returns 0 on success.
2026 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2027 void __user *buffer, size_t *lenp, loff_t *ppos)
2029 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2033 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2034 * @table: the sysctl table
2035 * @write: %TRUE if this is a write to the sysctl file
2036 * @filp: the file structure
2037 * @buffer: the user buffer
2038 * @lenp: the size of the user buffer
2039 * @ppos: file position
2041 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2042 * values from/to the user buffer, treated as an ASCII string. The values
2043 * are treated as milliseconds, and converted to jiffies when they are stored.
2045 * This routine will ensure the values are within the range specified by
2046 * table->extra1 (min) and table->extra2 (max).
2048 * Returns 0 on success.
2050 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2052 void __user *buffer,
2053 size_t *lenp, loff_t *ppos)
2055 return do_proc_doulongvec_minmax(table, write, filp, buffer,
2056 lenp, ppos, HZ, 1000l);
2060 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2062 int write, void *data)
2065 if (*lvalp > LONG_MAX / HZ)
2067 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2073 lval = (unsigned long)-val;
2076 lval = (unsigned long)val;
2083 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2085 int write, void *data)
2088 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2090 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2096 lval = (unsigned long)-val;
2099 lval = (unsigned long)val;
2101 *lvalp = jiffies_to_clock_t(lval);
2106 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2108 int write, void *data)
2111 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2117 lval = (unsigned long)-val;
2120 lval = (unsigned long)val;
2122 *lvalp = jiffies_to_msecs(lval);
2128 * proc_dointvec_jiffies - read a vector of integers as seconds
2129 * @table: the sysctl table
2130 * @write: %TRUE if this is a write to the sysctl file
2131 * @filp: the file structure
2132 * @buffer: the user buffer
2133 * @lenp: the size of the user buffer
2134 * @ppos: file position
2136 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2137 * values from/to the user buffer, treated as an ASCII string.
2138 * The values read are assumed to be in seconds, and are converted into
2141 * Returns 0 on success.
2143 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2144 void __user *buffer, size_t *lenp, loff_t *ppos)
2146 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2147 do_proc_dointvec_jiffies_conv,NULL);
2151 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2152 * @table: the sysctl table
2153 * @write: %TRUE if this is a write to the sysctl file
2154 * @filp: the file structure
2155 * @buffer: the user buffer
2156 * @lenp: the size of the user buffer
2157 * @ppos: pointer to the file position
2159 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2160 * values from/to the user buffer, treated as an ASCII string.
2161 * The values read are assumed to be in 1/USER_HZ seconds, and
2162 * are converted into jiffies.
2164 * Returns 0 on success.
2166 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2167 void __user *buffer, size_t *lenp, loff_t *ppos)
2169 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2170 do_proc_dointvec_userhz_jiffies_conv,NULL);
2174 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2175 * @table: the sysctl table
2176 * @write: %TRUE if this is a write to the sysctl file
2177 * @filp: the file structure
2178 * @buffer: the user buffer
2179 * @lenp: the size of the user buffer
2180 * @ppos: file position
2181 * @ppos: the current position in the file
2183 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2184 * values from/to the user buffer, treated as an ASCII string.
2185 * The values read are assumed to be in 1/1000 seconds, and
2186 * are converted into jiffies.
2188 * Returns 0 on success.
2190 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2191 void __user *buffer, size_t *lenp, loff_t *ppos)
2193 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2194 do_proc_dointvec_ms_jiffies_conv, NULL);
2197 #else /* CONFIG_PROC_FS */
2199 int proc_dostring(ctl_table *table, int write, struct file *filp,
2200 void __user *buffer, size_t *lenp, loff_t *ppos)
2205 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
2206 void __user *buffer, size_t *lenp, loff_t *ppos)
2211 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2212 void __user *buffer, size_t *lenp, loff_t *ppos)
2217 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2218 void __user *buffer, size_t *lenp, loff_t *ppos)
2223 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2224 void __user *buffer, size_t *lenp, loff_t *ppos)
2229 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2230 void __user *buffer, size_t *lenp, loff_t *ppos)
2235 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2236 void __user *buffer, size_t *lenp, loff_t *ppos)
2241 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2242 void __user *buffer, size_t *lenp, loff_t *ppos)
2247 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2248 void __user *buffer, size_t *lenp, loff_t *ppos)
2253 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2255 void __user *buffer,
2256 size_t *lenp, loff_t *ppos)
2262 #endif /* CONFIG_PROC_FS */
2266 * General sysctl support routines
2269 /* The generic string strategy routine: */
2270 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2271 void __user *oldval, size_t __user *oldlenp,
2272 void __user *newval, size_t newlen, void **context)
2274 if (!table->data || !table->maxlen)
2277 if (oldval && oldlenp) {
2279 if (get_user(bufsize, oldlenp))
2282 size_t len = strlen(table->data), copied;
2284 /* This shouldn't trigger for a well-formed sysctl */
2285 if (len > table->maxlen)
2286 len = table->maxlen;
2288 /* Copy up to a max of bufsize-1 bytes of the string */
2289 copied = (len >= bufsize) ? bufsize - 1 : len;
2291 if (copy_to_user(oldval, table->data, copied) ||
2292 put_user(0, (char __user *)(oldval + copied)))
2294 if (put_user(len, oldlenp))
2298 if (newval && newlen) {
2299 size_t len = newlen;
2300 if (len > table->maxlen)
2301 len = table->maxlen;
2302 if(copy_from_user(table->data, newval, len))
2304 if (len == table->maxlen)
2306 ((char *) table->data)[len] = 0;
2312 * This function makes sure that all of the integers in the vector
2313 * are between the minimum and maximum values given in the arrays
2314 * table->extra1 and table->extra2, respectively.
2316 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2317 void __user *oldval, size_t __user *oldlenp,
2318 void __user *newval, size_t newlen, void **context)
2321 if (newval && newlen) {
2322 int __user *vec = (int __user *) newval;
2323 int *min = (int *) table->extra1;
2324 int *max = (int *) table->extra2;
2328 if (newlen % sizeof(int) != 0)
2331 if (!table->extra1 && !table->extra2)
2334 if (newlen > table->maxlen)
2335 newlen = table->maxlen;
2336 length = newlen / sizeof(int);
2338 for (i = 0; i < length; i++) {
2340 if (get_user(value, vec + i))
2342 if (min && value < min[i])
2344 if (max && value > max[i])
2351 /* Strategy function to convert jiffies to seconds */
2352 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2353 void __user *oldval, size_t __user *oldlenp,
2354 void __user *newval, size_t newlen, void **context)
2359 if (get_user(olen, oldlenp))
2361 if (olen!=sizeof(int))
2364 if (put_user(*(int *)(table->data)/HZ, (int __user *)oldval) ||
2365 (oldlenp && put_user(sizeof(int),oldlenp)))
2368 if (newval && newlen) {
2370 if (newlen != sizeof(int))
2372 if (get_user(new, (int __user *)newval))
2374 *(int *)(table->data) = new*HZ;
2379 /* Strategy function to convert jiffies to seconds */
2380 int sysctl_ms_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(jiffies_to_msecs(*(int *)(table->data)), (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) = msecs_to_jiffies(new);
2407 #else /* CONFIG_SYSCTL */
2410 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2415 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2416 void __user *oldval, size_t __user *oldlenp,
2417 void __user *newval, size_t newlen, void **context)
2422 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2423 void __user *oldval, size_t __user *oldlenp,
2424 void __user *newval, size_t newlen, void **context)
2429 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2430 void __user *oldval, size_t __user *oldlenp,
2431 void __user *newval, size_t newlen, void **context)
2436 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2437 void __user *oldval, size_t __user *oldlenp,
2438 void __user *newval, size_t newlen, void **context)
2443 int proc_dostring(ctl_table *table, int write, struct file *filp,
2444 void __user *buffer, size_t *lenp, loff_t *ppos)
2449 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2450 void __user *buffer, size_t *lenp, loff_t *ppos)
2455 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2456 void __user *buffer, size_t *lenp, loff_t *ppos)
2461 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2462 void __user *buffer, size_t *lenp, loff_t *ppos)
2467 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2468 void __user *buffer, size_t *lenp, loff_t *ppos)
2473 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2474 void __user *buffer, size_t *lenp, loff_t *ppos)
2479 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2480 void __user *buffer, size_t *lenp, loff_t *ppos)
2485 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2486 void __user *buffer, size_t *lenp, loff_t *ppos)
2491 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2493 void __user *buffer,
2494 size_t *lenp, loff_t *ppos)
2499 struct ctl_table_header * register_sysctl_table(ctl_table * table,
2505 void unregister_sysctl_table(struct ctl_table_header * table)
2509 #endif /* CONFIG_SYSCTL */
2512 * No sense putting this after each symbol definition, twice,
2513 * exception granted :-)
2515 EXPORT_SYMBOL(proc_dointvec);
2516 EXPORT_SYMBOL(proc_dointvec_jiffies);
2517 EXPORT_SYMBOL(proc_dointvec_minmax);
2518 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2519 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2520 EXPORT_SYMBOL(proc_dostring);
2521 EXPORT_SYMBOL(proc_doulongvec_minmax);
2522 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2523 EXPORT_SYMBOL(register_sysctl_table);
2524 EXPORT_SYMBOL(sysctl_intvec);
2525 EXPORT_SYMBOL(sysctl_jiffies);
2526 EXPORT_SYMBOL(sysctl_ms_jiffies);
2527 EXPORT_SYMBOL(sysctl_string);
2528 EXPORT_SYMBOL(unregister_sysctl_table);