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;
81 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
82 static int maxolduid = 65535;
84 static int min_percpu_pagelist_fract = 8;
86 static int ngroups_max = NGROUPS_MAX;
89 extern char modprobe_path[];
91 #ifdef CONFIG_CHR_DEV_SG
92 extern int sg_big_buff;
95 extern size_t shm_ctlmax;
96 extern size_t shm_ctlall;
97 extern int shm_ctlmni;
98 extern int msg_ctlmax;
99 extern int msg_ctlmnb;
100 extern int msg_ctlmni;
101 extern int sem_ctls[];
105 extern char reboot_command [];
106 extern int stop_a_enabled;
107 extern int scons_pwroff;
111 extern int pwrsw_enabled;
112 extern int unaligned_enabled;
116 #ifdef CONFIG_MATHEMU
117 extern int sysctl_ieee_emulation_warnings;
119 extern int sysctl_userprocess_debug;
120 extern int spin_retry;
123 extern int sysctl_hz_timer;
125 #ifdef CONFIG_BSD_PROCESS_ACCT
126 extern int acct_parm[];
130 extern int no_unaligned_warning;
133 #ifdef CONFIG_RT_MUTEXES
134 extern int max_lock_depth;
137 static int parse_table(int __user *, int, void __user *, size_t __user *, void __user *, size_t,
138 ctl_table *, void **);
139 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
140 void __user *buffer, size_t *lenp, loff_t *ppos);
142 static ctl_table root_table[];
143 static struct ctl_table_header root_table_header =
144 { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
146 static ctl_table kern_table[];
147 static ctl_table vm_table[];
148 static ctl_table fs_table[];
149 static ctl_table debug_table[];
150 static ctl_table dev_table[];
151 extern ctl_table random_table[];
152 #ifdef CONFIG_UNIX98_PTYS
153 extern ctl_table pty_table[];
155 #ifdef CONFIG_INOTIFY_USER
156 extern ctl_table inotify_table[];
159 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
160 int sysctl_legacy_va_layout;
163 /* /proc declarations: */
165 #ifdef CONFIG_PROC_FS
167 static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
168 static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
169 static int proc_opensys(struct inode *, struct file *);
171 struct file_operations proc_sys_file_operations = {
172 .open = proc_opensys,
173 .read = proc_readsys,
174 .write = proc_writesys,
177 extern struct proc_dir_entry *proc_sys_root;
179 static void register_proc_table(ctl_table *, struct proc_dir_entry *, void *);
180 static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
183 /* The default sysctl tables: */
185 static ctl_table root_table[] = {
187 .ctl_name = CTL_KERN,
188 .procname = "kernel",
213 .ctl_name = CTL_DEBUG,
216 .child = debug_table,
228 static ctl_table kern_table[] = {
230 .ctl_name = KERN_OSTYPE,
231 .procname = "ostype",
232 .data = system_utsname.sysname,
233 .maxlen = sizeof(system_utsname.sysname),
235 .proc_handler = &proc_doutsstring,
236 .strategy = &sysctl_string,
239 .ctl_name = KERN_OSRELEASE,
240 .procname = "osrelease",
241 .data = system_utsname.release,
242 .maxlen = sizeof(system_utsname.release),
244 .proc_handler = &proc_doutsstring,
245 .strategy = &sysctl_string,
248 .ctl_name = KERN_VERSION,
249 .procname = "version",
250 .data = system_utsname.version,
251 .maxlen = sizeof(system_utsname.version),
253 .proc_handler = &proc_doutsstring,
254 .strategy = &sysctl_string,
257 .ctl_name = KERN_NODENAME,
258 .procname = "hostname",
259 .data = system_utsname.nodename,
260 .maxlen = sizeof(system_utsname.nodename),
262 .proc_handler = &proc_doutsstring,
263 .strategy = &sysctl_string,
266 .ctl_name = KERN_DOMAINNAME,
267 .procname = "domainname",
268 .data = system_utsname.domainname,
269 .maxlen = sizeof(system_utsname.domainname),
271 .proc_handler = &proc_doutsstring,
272 .strategy = &sysctl_string,
275 .ctl_name = KERN_PANIC,
277 .data = &panic_timeout,
278 .maxlen = sizeof(int),
280 .proc_handler = &proc_dointvec,
283 .ctl_name = KERN_CORE_USES_PID,
284 .procname = "core_uses_pid",
285 .data = &core_uses_pid,
286 .maxlen = sizeof(int),
288 .proc_handler = &proc_dointvec,
291 .ctl_name = KERN_CORE_PATTERN,
292 .procname = "core_pattern",
293 .data = core_pattern,
296 .proc_handler = &proc_dostring,
297 .strategy = &sysctl_string,
300 .ctl_name = KERN_TAINTED,
301 .procname = "tainted",
303 .maxlen = sizeof(int),
305 .proc_handler = &proc_dointvec,
308 .ctl_name = KERN_CAP_BSET,
309 .procname = "cap-bound",
311 .maxlen = sizeof(kernel_cap_t),
313 .proc_handler = &proc_dointvec_bset,
315 #ifdef CONFIG_BLK_DEV_INITRD
317 .ctl_name = KERN_REALROOTDEV,
318 .procname = "real-root-dev",
319 .data = &real_root_dev,
320 .maxlen = sizeof(int),
322 .proc_handler = &proc_dointvec,
327 .ctl_name = KERN_SPARC_REBOOT,
328 .procname = "reboot-cmd",
329 .data = reboot_command,
332 .proc_handler = &proc_dostring,
333 .strategy = &sysctl_string,
336 .ctl_name = KERN_SPARC_STOP_A,
337 .procname = "stop-a",
338 .data = &stop_a_enabled,
339 .maxlen = sizeof (int),
341 .proc_handler = &proc_dointvec,
344 .ctl_name = KERN_SPARC_SCONS_PWROFF,
345 .procname = "scons-poweroff",
346 .data = &scons_pwroff,
347 .maxlen = sizeof (int),
349 .proc_handler = &proc_dointvec,
354 .ctl_name = KERN_HPPA_PWRSW,
355 .procname = "soft-power",
356 .data = &pwrsw_enabled,
357 .maxlen = sizeof (int),
359 .proc_handler = &proc_dointvec,
362 .ctl_name = KERN_HPPA_UNALIGNED,
363 .procname = "unaligned-trap",
364 .data = &unaligned_enabled,
365 .maxlen = sizeof (int),
367 .proc_handler = &proc_dointvec,
371 .ctl_name = KERN_CTLALTDEL,
372 .procname = "ctrl-alt-del",
374 .maxlen = sizeof(int),
376 .proc_handler = &proc_dointvec,
379 .ctl_name = KERN_PRINTK,
380 .procname = "printk",
381 .data = &console_loglevel,
382 .maxlen = 4*sizeof(int),
384 .proc_handler = &proc_dointvec,
388 .ctl_name = KERN_MODPROBE,
389 .procname = "modprobe",
390 .data = &modprobe_path,
391 .maxlen = KMOD_PATH_LEN,
393 .proc_handler = &proc_dostring,
394 .strategy = &sysctl_string,
397 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
399 .ctl_name = KERN_HOTPLUG,
400 .procname = "hotplug",
401 .data = &uevent_helper,
402 .maxlen = UEVENT_HELPER_PATH_LEN,
404 .proc_handler = &proc_dostring,
405 .strategy = &sysctl_string,
408 #ifdef CONFIG_CHR_DEV_SG
410 .ctl_name = KERN_SG_BIG_BUFF,
411 .procname = "sg-big-buff",
412 .data = &sg_big_buff,
413 .maxlen = sizeof (int),
415 .proc_handler = &proc_dointvec,
418 #ifdef CONFIG_BSD_PROCESS_ACCT
420 .ctl_name = KERN_ACCT,
423 .maxlen = 3*sizeof(int),
425 .proc_handler = &proc_dointvec,
428 #ifdef CONFIG_SYSVIPC
430 .ctl_name = KERN_SHMMAX,
431 .procname = "shmmax",
433 .maxlen = sizeof (size_t),
435 .proc_handler = &proc_doulongvec_minmax,
438 .ctl_name = KERN_SHMALL,
439 .procname = "shmall",
441 .maxlen = sizeof (size_t),
443 .proc_handler = &proc_doulongvec_minmax,
446 .ctl_name = KERN_SHMMNI,
447 .procname = "shmmni",
449 .maxlen = sizeof (int),
451 .proc_handler = &proc_dointvec,
454 .ctl_name = KERN_MSGMAX,
455 .procname = "msgmax",
457 .maxlen = sizeof (int),
459 .proc_handler = &proc_dointvec,
462 .ctl_name = KERN_MSGMNI,
463 .procname = "msgmni",
465 .maxlen = sizeof (int),
467 .proc_handler = &proc_dointvec,
470 .ctl_name = KERN_MSGMNB,
471 .procname = "msgmnb",
473 .maxlen = sizeof (int),
475 .proc_handler = &proc_dointvec,
478 .ctl_name = KERN_SEM,
481 .maxlen = 4*sizeof (int),
483 .proc_handler = &proc_dointvec,
486 #ifdef CONFIG_MAGIC_SYSRQ
488 .ctl_name = KERN_SYSRQ,
490 .data = &sysrq_enabled,
491 .maxlen = sizeof (int),
493 .proc_handler = &proc_dointvec,
497 .ctl_name = KERN_CADPID,
498 .procname = "cad_pid",
500 .maxlen = sizeof (int),
502 .proc_handler = &proc_dointvec,
505 .ctl_name = KERN_MAX_THREADS,
506 .procname = "threads-max",
507 .data = &max_threads,
508 .maxlen = sizeof(int),
510 .proc_handler = &proc_dointvec,
513 .ctl_name = KERN_RANDOM,
514 .procname = "random",
516 .child = random_table,
518 #ifdef CONFIG_UNIX98_PTYS
520 .ctl_name = KERN_PTY,
527 .ctl_name = KERN_OVERFLOWUID,
528 .procname = "overflowuid",
529 .data = &overflowuid,
530 .maxlen = sizeof(int),
532 .proc_handler = &proc_dointvec_minmax,
533 .strategy = &sysctl_intvec,
534 .extra1 = &minolduid,
535 .extra2 = &maxolduid,
538 .ctl_name = KERN_OVERFLOWGID,
539 .procname = "overflowgid",
540 .data = &overflowgid,
541 .maxlen = sizeof(int),
543 .proc_handler = &proc_dointvec_minmax,
544 .strategy = &sysctl_intvec,
545 .extra1 = &minolduid,
546 .extra2 = &maxolduid,
549 #ifdef CONFIG_MATHEMU
551 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
552 .procname = "ieee_emulation_warnings",
553 .data = &sysctl_ieee_emulation_warnings,
554 .maxlen = sizeof(int),
556 .proc_handler = &proc_dointvec,
559 #ifdef CONFIG_NO_IDLE_HZ
561 .ctl_name = KERN_HZ_TIMER,
562 .procname = "hz_timer",
563 .data = &sysctl_hz_timer,
564 .maxlen = sizeof(int),
566 .proc_handler = &proc_dointvec,
570 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
571 .procname = "userprocess_debug",
572 .data = &sysctl_userprocess_debug,
573 .maxlen = sizeof(int),
575 .proc_handler = &proc_dointvec,
579 .ctl_name = KERN_PIDMAX,
580 .procname = "pid_max",
582 .maxlen = sizeof (int),
584 .proc_handler = &proc_dointvec_minmax,
585 .strategy = sysctl_intvec,
586 .extra1 = &pid_max_min,
587 .extra2 = &pid_max_max,
590 .ctl_name = KERN_PANIC_ON_OOPS,
591 .procname = "panic_on_oops",
592 .data = &panic_on_oops,
593 .maxlen = sizeof(int),
595 .proc_handler = &proc_dointvec,
598 .ctl_name = KERN_PRINTK_RATELIMIT,
599 .procname = "printk_ratelimit",
600 .data = &printk_ratelimit_jiffies,
601 .maxlen = sizeof(int),
603 .proc_handler = &proc_dointvec_jiffies,
604 .strategy = &sysctl_jiffies,
607 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
608 .procname = "printk_ratelimit_burst",
609 .data = &printk_ratelimit_burst,
610 .maxlen = sizeof(int),
612 .proc_handler = &proc_dointvec,
615 .ctl_name = KERN_NGROUPS_MAX,
616 .procname = "ngroups_max",
617 .data = &ngroups_max,
618 .maxlen = sizeof (int),
620 .proc_handler = &proc_dointvec,
622 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
624 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
625 .procname = "unknown_nmi_panic",
626 .data = &unknown_nmi_panic,
627 .maxlen = sizeof (int),
629 .proc_handler = &proc_dointvec,
632 #if defined(CONFIG_X86)
634 .ctl_name = KERN_BOOTLOADER_TYPE,
635 .procname = "bootloader_type",
636 .data = &bootloader_type,
637 .maxlen = sizeof (int),
639 .proc_handler = &proc_dointvec,
642 #if defined(CONFIG_MMU)
644 .ctl_name = KERN_RANDOMIZE,
645 .procname = "randomize_va_space",
646 .data = &randomize_va_space,
647 .maxlen = sizeof(int),
649 .proc_handler = &proc_dointvec,
652 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
654 .ctl_name = KERN_SPIN_RETRY,
655 .procname = "spin_retry",
657 .maxlen = sizeof (int),
659 .proc_handler = &proc_dointvec,
662 #ifdef CONFIG_ACPI_SLEEP
664 .ctl_name = KERN_ACPI_VIDEO_FLAGS,
665 .procname = "acpi_video_flags",
666 .data = &acpi_video_flags,
667 .maxlen = sizeof (unsigned long),
669 .proc_handler = &proc_doulongvec_minmax,
674 .ctl_name = KERN_IA64_UNALIGNED,
675 .procname = "ignore-unaligned-usertrap",
676 .data = &no_unaligned_warning,
677 .maxlen = sizeof (int),
679 .proc_handler = &proc_dointvec,
684 .ctl_name = KERN_COMPAT_LOG,
685 .procname = "compat-log",
687 .maxlen = sizeof (int),
689 .proc_handler = &proc_dointvec,
692 #ifdef CONFIG_RT_MUTEXES
694 .ctl_name = KERN_MAX_LOCK_DEPTH,
695 .procname = "max_lock_depth",
696 .data = &max_lock_depth,
697 .maxlen = sizeof(int),
699 .proc_handler = &proc_dointvec,
706 /* Constants for minimum and maximum testing in vm_table.
707 We use these as one-element integer vectors. */
709 static int one_hundred = 100;
712 static ctl_table vm_table[] = {
714 .ctl_name = VM_OVERCOMMIT_MEMORY,
715 .procname = "overcommit_memory",
716 .data = &sysctl_overcommit_memory,
717 .maxlen = sizeof(sysctl_overcommit_memory),
719 .proc_handler = &proc_dointvec,
722 .ctl_name = VM_PANIC_ON_OOM,
723 .procname = "panic_on_oom",
724 .data = &sysctl_panic_on_oom,
725 .maxlen = sizeof(sysctl_panic_on_oom),
727 .proc_handler = &proc_dointvec,
730 .ctl_name = VM_OVERCOMMIT_RATIO,
731 .procname = "overcommit_ratio",
732 .data = &sysctl_overcommit_ratio,
733 .maxlen = sizeof(sysctl_overcommit_ratio),
735 .proc_handler = &proc_dointvec,
738 .ctl_name = VM_PAGE_CLUSTER,
739 .procname = "page-cluster",
740 .data = &page_cluster,
741 .maxlen = sizeof(int),
743 .proc_handler = &proc_dointvec,
746 .ctl_name = VM_DIRTY_BACKGROUND,
747 .procname = "dirty_background_ratio",
748 .data = &dirty_background_ratio,
749 .maxlen = sizeof(dirty_background_ratio),
751 .proc_handler = &proc_dointvec_minmax,
752 .strategy = &sysctl_intvec,
754 .extra2 = &one_hundred,
757 .ctl_name = VM_DIRTY_RATIO,
758 .procname = "dirty_ratio",
759 .data = &vm_dirty_ratio,
760 .maxlen = sizeof(vm_dirty_ratio),
762 .proc_handler = &proc_dointvec_minmax,
763 .strategy = &sysctl_intvec,
765 .extra2 = &one_hundred,
768 .ctl_name = VM_DIRTY_WB_CS,
769 .procname = "dirty_writeback_centisecs",
770 .data = &dirty_writeback_interval,
771 .maxlen = sizeof(dirty_writeback_interval),
773 .proc_handler = &dirty_writeback_centisecs_handler,
776 .ctl_name = VM_DIRTY_EXPIRE_CS,
777 .procname = "dirty_expire_centisecs",
778 .data = &dirty_expire_interval,
779 .maxlen = sizeof(dirty_expire_interval),
781 .proc_handler = &proc_dointvec_userhz_jiffies,
784 .ctl_name = VM_NR_PDFLUSH_THREADS,
785 .procname = "nr_pdflush_threads",
786 .data = &nr_pdflush_threads,
787 .maxlen = sizeof nr_pdflush_threads,
788 .mode = 0444 /* read-only*/,
789 .proc_handler = &proc_dointvec,
792 .ctl_name = VM_SWAPPINESS,
793 .procname = "swappiness",
794 .data = &vm_swappiness,
795 .maxlen = sizeof(vm_swappiness),
797 .proc_handler = &proc_dointvec_minmax,
798 .strategy = &sysctl_intvec,
800 .extra2 = &one_hundred,
802 #ifdef CONFIG_HUGETLB_PAGE
804 .ctl_name = VM_HUGETLB_PAGES,
805 .procname = "nr_hugepages",
806 .data = &max_huge_pages,
807 .maxlen = sizeof(unsigned long),
809 .proc_handler = &hugetlb_sysctl_handler,
810 .extra1 = (void *)&hugetlb_zero,
811 .extra2 = (void *)&hugetlb_infinity,
814 .ctl_name = VM_HUGETLB_GROUP,
815 .procname = "hugetlb_shm_group",
816 .data = &sysctl_hugetlb_shm_group,
817 .maxlen = sizeof(gid_t),
819 .proc_handler = &proc_dointvec,
823 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
824 .procname = "lowmem_reserve_ratio",
825 .data = &sysctl_lowmem_reserve_ratio,
826 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
828 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
829 .strategy = &sysctl_intvec,
832 .ctl_name = VM_DROP_PAGECACHE,
833 .procname = "drop_caches",
834 .data = &sysctl_drop_caches,
835 .maxlen = sizeof(int),
837 .proc_handler = drop_caches_sysctl_handler,
838 .strategy = &sysctl_intvec,
841 .ctl_name = VM_MIN_FREE_KBYTES,
842 .procname = "min_free_kbytes",
843 .data = &min_free_kbytes,
844 .maxlen = sizeof(min_free_kbytes),
846 .proc_handler = &min_free_kbytes_sysctl_handler,
847 .strategy = &sysctl_intvec,
851 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
852 .procname = "percpu_pagelist_fraction",
853 .data = &percpu_pagelist_fraction,
854 .maxlen = sizeof(percpu_pagelist_fraction),
856 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
857 .strategy = &sysctl_intvec,
858 .extra1 = &min_percpu_pagelist_fract,
862 .ctl_name = VM_MAX_MAP_COUNT,
863 .procname = "max_map_count",
864 .data = &sysctl_max_map_count,
865 .maxlen = sizeof(sysctl_max_map_count),
867 .proc_handler = &proc_dointvec
871 .ctl_name = VM_LAPTOP_MODE,
872 .procname = "laptop_mode",
873 .data = &laptop_mode,
874 .maxlen = sizeof(laptop_mode),
876 .proc_handler = &proc_dointvec_jiffies,
877 .strategy = &sysctl_jiffies,
880 .ctl_name = VM_BLOCK_DUMP,
881 .procname = "block_dump",
883 .maxlen = sizeof(block_dump),
885 .proc_handler = &proc_dointvec,
886 .strategy = &sysctl_intvec,
890 .ctl_name = VM_VFS_CACHE_PRESSURE,
891 .procname = "vfs_cache_pressure",
892 .data = &sysctl_vfs_cache_pressure,
893 .maxlen = sizeof(sysctl_vfs_cache_pressure),
895 .proc_handler = &proc_dointvec,
896 .strategy = &sysctl_intvec,
899 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
901 .ctl_name = VM_LEGACY_VA_LAYOUT,
902 .procname = "legacy_va_layout",
903 .data = &sysctl_legacy_va_layout,
904 .maxlen = sizeof(sysctl_legacy_va_layout),
906 .proc_handler = &proc_dointvec,
907 .strategy = &sysctl_intvec,
913 .ctl_name = VM_SWAP_TOKEN_TIMEOUT,
914 .procname = "swap_token_timeout",
915 .data = &swap_token_default_timeout,
916 .maxlen = sizeof(swap_token_default_timeout),
918 .proc_handler = &proc_dointvec_jiffies,
919 .strategy = &sysctl_jiffies,
924 .ctl_name = VM_ZONE_RECLAIM_MODE,
925 .procname = "zone_reclaim_mode",
926 .data = &zone_reclaim_mode,
927 .maxlen = sizeof(zone_reclaim_mode),
929 .proc_handler = &proc_dointvec,
930 .strategy = &sysctl_intvec,
934 .ctl_name = VM_MIN_UNMAPPED,
935 .procname = "min_unmapped_ratio",
936 .data = &sysctl_min_unmapped_ratio,
937 .maxlen = sizeof(sysctl_min_unmapped_ratio),
939 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
940 .strategy = &sysctl_intvec,
942 .extra2 = &one_hundred,
947 .ctl_name = VM_VDSO_ENABLED,
948 .procname = "vdso_enabled",
949 .data = &vdso_enabled,
950 .maxlen = sizeof(vdso_enabled),
952 .proc_handler = &proc_dointvec,
953 .strategy = &sysctl_intvec,
960 static ctl_table fs_table[] = {
962 .ctl_name = FS_NRINODE,
963 .procname = "inode-nr",
964 .data = &inodes_stat,
965 .maxlen = 2*sizeof(int),
967 .proc_handler = &proc_dointvec,
970 .ctl_name = FS_STATINODE,
971 .procname = "inode-state",
972 .data = &inodes_stat,
973 .maxlen = 7*sizeof(int),
975 .proc_handler = &proc_dointvec,
978 .ctl_name = FS_NRFILE,
979 .procname = "file-nr",
981 .maxlen = 3*sizeof(int),
983 .proc_handler = &proc_nr_files,
986 .ctl_name = FS_MAXFILE,
987 .procname = "file-max",
988 .data = &files_stat.max_files,
989 .maxlen = sizeof(int),
991 .proc_handler = &proc_dointvec,
994 .ctl_name = FS_DENTRY,
995 .procname = "dentry-state",
996 .data = &dentry_stat,
997 .maxlen = 6*sizeof(int),
999 .proc_handler = &proc_dointvec,
1002 .ctl_name = FS_OVERFLOWUID,
1003 .procname = "overflowuid",
1004 .data = &fs_overflowuid,
1005 .maxlen = sizeof(int),
1007 .proc_handler = &proc_dointvec_minmax,
1008 .strategy = &sysctl_intvec,
1009 .extra1 = &minolduid,
1010 .extra2 = &maxolduid,
1013 .ctl_name = FS_OVERFLOWGID,
1014 .procname = "overflowgid",
1015 .data = &fs_overflowgid,
1016 .maxlen = sizeof(int),
1018 .proc_handler = &proc_dointvec_minmax,
1019 .strategy = &sysctl_intvec,
1020 .extra1 = &minolduid,
1021 .extra2 = &maxolduid,
1024 .ctl_name = FS_LEASES,
1025 .procname = "leases-enable",
1026 .data = &leases_enable,
1027 .maxlen = sizeof(int),
1029 .proc_handler = &proc_dointvec,
1031 #ifdef CONFIG_DNOTIFY
1033 .ctl_name = FS_DIR_NOTIFY,
1034 .procname = "dir-notify-enable",
1035 .data = &dir_notify_enable,
1036 .maxlen = sizeof(int),
1038 .proc_handler = &proc_dointvec,
1043 .ctl_name = FS_LEASE_TIME,
1044 .procname = "lease-break-time",
1045 .data = &lease_break_time,
1046 .maxlen = sizeof(int),
1048 .proc_handler = &proc_dointvec,
1051 .ctl_name = FS_AIO_NR,
1052 .procname = "aio-nr",
1054 .maxlen = sizeof(aio_nr),
1056 .proc_handler = &proc_doulongvec_minmax,
1059 .ctl_name = FS_AIO_MAX_NR,
1060 .procname = "aio-max-nr",
1061 .data = &aio_max_nr,
1062 .maxlen = sizeof(aio_max_nr),
1064 .proc_handler = &proc_doulongvec_minmax,
1066 #ifdef CONFIG_INOTIFY_USER
1068 .ctl_name = FS_INOTIFY,
1069 .procname = "inotify",
1071 .child = inotify_table,
1076 .ctl_name = KERN_SETUID_DUMPABLE,
1077 .procname = "suid_dumpable",
1078 .data = &suid_dumpable,
1079 .maxlen = sizeof(int),
1081 .proc_handler = &proc_dointvec,
1086 static ctl_table debug_table[] = {
1090 static ctl_table dev_table[] = {
1094 extern void init_irq_proc (void);
1096 static DEFINE_SPINLOCK(sysctl_lock);
1098 /* called under sysctl_lock */
1099 static int use_table(struct ctl_table_header *p)
1101 if (unlikely(p->unregistering))
1107 /* called under sysctl_lock */
1108 static void unuse_table(struct ctl_table_header *p)
1111 if (unlikely(p->unregistering))
1112 complete(p->unregistering);
1115 /* called under sysctl_lock, will reacquire if has to wait */
1116 static void start_unregistering(struct ctl_table_header *p)
1119 * if p->used is 0, nobody will ever touch that entry again;
1120 * we'll eliminate all paths to it before dropping sysctl_lock
1122 if (unlikely(p->used)) {
1123 struct completion wait;
1124 init_completion(&wait);
1125 p->unregistering = &wait;
1126 spin_unlock(&sysctl_lock);
1127 wait_for_completion(&wait);
1128 spin_lock(&sysctl_lock);
1131 * do not remove from the list until nobody holds it; walking the
1132 * list in do_sysctl() relies on that.
1134 list_del_init(&p->ctl_entry);
1137 void __init sysctl_init(void)
1139 #ifdef CONFIG_PROC_FS
1140 register_proc_table(root_table, proc_sys_root, &root_table_header);
1145 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1146 void __user *newval, size_t newlen)
1148 struct list_head *tmp;
1149 int error = -ENOTDIR;
1151 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1155 if (!oldlenp || get_user(old_len, oldlenp))
1158 spin_lock(&sysctl_lock);
1159 tmp = &root_table_header.ctl_entry;
1161 struct ctl_table_header *head =
1162 list_entry(tmp, struct ctl_table_header, ctl_entry);
1163 void *context = NULL;
1165 if (!use_table(head))
1168 spin_unlock(&sysctl_lock);
1170 error = parse_table(name, nlen, oldval, oldlenp,
1171 newval, newlen, head->ctl_table,
1175 spin_lock(&sysctl_lock);
1177 if (error != -ENOTDIR)
1179 } while ((tmp = tmp->next) != &root_table_header.ctl_entry);
1180 spin_unlock(&sysctl_lock);
1184 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1186 struct __sysctl_args tmp;
1189 if (copy_from_user(&tmp, args, sizeof(tmp)))
1193 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1194 tmp.newval, tmp.newlen);
1200 * ctl_perm does NOT grant the superuser all rights automatically, because
1201 * some sysctl variables are readonly even to root.
1204 static int test_perm(int mode, int op)
1208 else if (in_egroup_p(0))
1210 if ((mode & op & 0007) == op)
1215 static inline int ctl_perm(ctl_table *table, int op)
1218 error = security_sysctl(table, op);
1221 return test_perm(table->mode, op);
1224 static int parse_table(int __user *name, int nlen,
1225 void __user *oldval, size_t __user *oldlenp,
1226 void __user *newval, size_t newlen,
1227 ctl_table *table, void **context)
1233 if (get_user(n, name))
1235 for ( ; table->ctl_name; table++) {
1236 if (n == table->ctl_name || table->ctl_name == CTL_ANY) {
1239 if (ctl_perm(table, 001))
1241 if (table->strategy) {
1242 error = table->strategy(
1245 newval, newlen, context);
1251 table = table->child;
1254 error = do_sysctl_strategy(table, name, nlen,
1256 newval, newlen, context);
1263 /* Perform the actual read/write of a sysctl table entry. */
1264 int do_sysctl_strategy (ctl_table *table,
1265 int __user *name, int nlen,
1266 void __user *oldval, size_t __user *oldlenp,
1267 void __user *newval, size_t newlen, void **context)
1276 if (ctl_perm(table, op))
1279 if (table->strategy) {
1280 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1281 newval, newlen, context);
1288 /* If there is no strategy routine, or if the strategy returns
1289 * zero, proceed with automatic r/w */
1290 if (table->data && table->maxlen) {
1291 if (oldval && oldlenp) {
1292 if (get_user(len, oldlenp))
1295 if (len > table->maxlen)
1296 len = table->maxlen;
1297 if(copy_to_user(oldval, table->data, len))
1299 if(put_user(len, oldlenp))
1303 if (newval && newlen) {
1305 if (len > table->maxlen)
1306 len = table->maxlen;
1307 if(copy_from_user(table->data, newval, len))
1315 * register_sysctl_table - register a sysctl hierarchy
1316 * @table: the top-level table structure
1317 * @insert_at_head: whether the entry should be inserted in front or at the end
1319 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1320 * array. An entry with a ctl_name of 0 terminates the table.
1322 * The members of the &ctl_table structure are used as follows:
1324 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1325 * must be unique within that level of sysctl
1327 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1328 * enter a sysctl file
1330 * data - a pointer to data for use by proc_handler
1332 * maxlen - the maximum size in bytes of the data
1334 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1336 * child - a pointer to the child sysctl table if this entry is a directory, or
1339 * proc_handler - the text handler routine (described below)
1341 * strategy - the strategy routine (described below)
1343 * de - for internal use by the sysctl routines
1345 * extra1, extra2 - extra pointers usable by the proc handler routines
1347 * Leaf nodes in the sysctl tree will be represented by a single file
1348 * under /proc; non-leaf nodes will be represented by directories.
1350 * sysctl(2) can automatically manage read and write requests through
1351 * the sysctl table. The data and maxlen fields of the ctl_table
1352 * struct enable minimal validation of the values being written to be
1353 * performed, and the mode field allows minimal authentication.
1355 * More sophisticated management can be enabled by the provision of a
1356 * strategy routine with the table entry. This will be called before
1357 * any automatic read or write of the data is performed.
1359 * The strategy routine may return
1361 * < 0 - Error occurred (error is passed to user process)
1363 * 0 - OK - proceed with automatic read or write.
1365 * > 0 - OK - read or write has been done by the strategy routine, so
1366 * return immediately.
1368 * There must be a proc_handler routine for any terminal nodes
1369 * mirrored under /proc/sys (non-terminals are handled by a built-in
1370 * directory handler). Several default handlers are available to
1371 * cover common cases -
1373 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1374 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1375 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1377 * It is the handler's job to read the input buffer from user memory
1378 * and process it. The handler should return 0 on success.
1380 * This routine returns %NULL on a failure to register, and a pointer
1381 * to the table header on success.
1383 struct ctl_table_header *register_sysctl_table(ctl_table * table,
1386 struct ctl_table_header *tmp;
1387 tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1390 tmp->ctl_table = table;
1391 INIT_LIST_HEAD(&tmp->ctl_entry);
1393 tmp->unregistering = NULL;
1394 spin_lock(&sysctl_lock);
1396 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
1398 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1399 spin_unlock(&sysctl_lock);
1400 #ifdef CONFIG_PROC_FS
1401 register_proc_table(table, proc_sys_root, tmp);
1407 * unregister_sysctl_table - unregister a sysctl table hierarchy
1408 * @header: the header returned from register_sysctl_table
1410 * Unregisters the sysctl table and all children. proc entries may not
1411 * actually be removed until they are no longer used by anyone.
1413 void unregister_sysctl_table(struct ctl_table_header * header)
1416 spin_lock(&sysctl_lock);
1417 start_unregistering(header);
1418 #ifdef CONFIG_PROC_FS
1419 unregister_proc_table(header->ctl_table, proc_sys_root);
1421 spin_unlock(&sysctl_lock);
1429 #ifdef CONFIG_PROC_FS
1431 /* Scan the sysctl entries in table and add them all into /proc */
1432 static void register_proc_table(ctl_table * table, struct proc_dir_entry *root, void *set)
1434 struct proc_dir_entry *de;
1438 for (; table->ctl_name; table++) {
1439 /* Can't do anything without a proc name. */
1440 if (!table->procname)
1442 /* Maybe we can't do anything with it... */
1443 if (!table->proc_handler && !table->child) {
1444 printk(KERN_WARNING "SYSCTL: Can't register %s\n",
1449 len = strlen(table->procname);
1453 if (table->proc_handler)
1457 for (de = root->subdir; de; de = de->next) {
1458 if (proc_match(len, table->procname, de))
1461 /* If the subdir exists already, de is non-NULL */
1465 de = create_proc_entry(table->procname, mode, root);
1469 de->data = (void *) table;
1470 if (table->proc_handler)
1471 de->proc_fops = &proc_sys_file_operations;
1474 if (de->mode & S_IFDIR)
1475 register_proc_table(table->child, de, set);
1480 * Unregister a /proc sysctl table and any subdirectories.
1482 static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
1484 struct proc_dir_entry *de;
1485 for (; table->ctl_name; table++) {
1486 if (!(de = table->de))
1488 if (de->mode & S_IFDIR) {
1489 if (!table->child) {
1490 printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
1493 unregister_proc_table(table->child, de);
1495 /* Don't unregister directories which still have entries.. */
1501 * In any case, mark the entry as goner; we'll keep it
1502 * around if it's busy, but we'll know to do nothing with
1503 * its fields. We are under sysctl_lock here.
1507 /* Don't unregister proc entries that are still being used.. */
1508 if (atomic_read(&de->count))
1512 remove_proc_entry(table->procname, root);
1516 static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
1517 size_t count, loff_t *ppos)
1520 struct proc_dir_entry *de = PDE(file->f_dentry->d_inode);
1521 struct ctl_table *table;
1523 ssize_t error = -ENOTDIR;
1525 spin_lock(&sysctl_lock);
1526 if (de && de->data && use_table(de->set)) {
1528 * at that point we know that sysctl was not unregistered
1529 * and won't be until we finish
1531 spin_unlock(&sysctl_lock);
1532 table = (struct ctl_table *) de->data;
1533 if (!table || !table->proc_handler)
1536 op = (write ? 002 : 004);
1537 if (ctl_perm(table, op))
1540 /* careful: calling conventions are nasty here */
1542 error = (*table->proc_handler)(table, write, file,
1547 spin_lock(&sysctl_lock);
1548 unuse_table(de->set);
1550 spin_unlock(&sysctl_lock);
1554 static int proc_opensys(struct inode *inode, struct file *file)
1556 if (file->f_mode & FMODE_WRITE) {
1558 * sysctl entries that are not writable,
1559 * are _NOT_ writable, capabilities or not.
1561 if (!(inode->i_mode & S_IWUSR))
1568 static ssize_t proc_readsys(struct file * file, char __user * buf,
1569 size_t count, loff_t *ppos)
1571 return do_rw_proc(0, file, buf, count, ppos);
1574 static ssize_t proc_writesys(struct file * file, const char __user * buf,
1575 size_t count, loff_t *ppos)
1577 return do_rw_proc(1, file, (char __user *) buf, count, ppos);
1581 * proc_dostring - read a string sysctl
1582 * @table: the sysctl table
1583 * @write: %TRUE if this is a write to the sysctl file
1584 * @filp: the file structure
1585 * @buffer: the user buffer
1586 * @lenp: the size of the user buffer
1587 * @ppos: file position
1589 * Reads/writes a string from/to the user buffer. If the kernel
1590 * buffer provided is not large enough to hold the string, the
1591 * string is truncated. The copied string is %NULL-terminated.
1592 * If the string is being read by the user process, it is copied
1593 * and a newline '\n' is added. It is truncated if the buffer is
1596 * Returns 0 on success.
1598 int proc_dostring(ctl_table *table, int write, struct file *filp,
1599 void __user *buffer, size_t *lenp, loff_t *ppos)
1605 if (!table->data || !table->maxlen || !*lenp ||
1606 (*ppos && !write)) {
1614 while (len < *lenp) {
1615 if (get_user(c, p++))
1617 if (c == 0 || c == '\n')
1621 if (len >= table->maxlen)
1622 len = table->maxlen-1;
1623 if(copy_from_user(table->data, buffer, len))
1625 ((char *) table->data)[len] = 0;
1628 len = strlen(table->data);
1629 if (len > table->maxlen)
1630 len = table->maxlen;
1634 if(copy_to_user(buffer, table->data, len))
1637 if(put_user('\n', ((char __user *) buffer) + len))
1648 * Special case of dostring for the UTS structure. This has locks
1649 * to observe. Should this be in kernel/sys.c ????
1652 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
1653 void __user *buffer, size_t *lenp, loff_t *ppos)
1658 down_read(&uts_sem);
1659 r=proc_dostring(table,0,filp,buffer,lenp, ppos);
1662 down_write(&uts_sem);
1663 r=proc_dostring(table,1,filp,buffer,lenp, ppos);
1669 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1671 int write, void *data)
1674 *valp = *negp ? -*lvalp : *lvalp;
1679 *lvalp = (unsigned long)-val;
1682 *lvalp = (unsigned long)val;
1688 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1689 void __user *buffer, size_t *lenp, loff_t *ppos,
1690 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1691 int write, void *data),
1694 #define TMPBUFLEN 21
1695 int *i, vleft, first=1, neg, val;
1699 char buf[TMPBUFLEN], *p;
1700 char __user *s = buffer;
1702 if (!table->data || !table->maxlen || !*lenp ||
1703 (*ppos && !write)) {
1708 i = (int *) table->data;
1709 vleft = table->maxlen / sizeof(*i);
1713 conv = do_proc_dointvec_conv;
1715 for (; left && vleft--; i++, first=0) {
1730 if (len > sizeof(buf) - 1)
1731 len = sizeof(buf) - 1;
1732 if (copy_from_user(buf, s, len))
1736 if (*p == '-' && left > 1) {
1740 if (*p < '0' || *p > '9')
1743 lval = simple_strtoul(p, &p, 0);
1746 if ((len < left) && *p && !isspace(*p))
1753 if (conv(&neg, &lval, i, 1, data))
1760 if (conv(&neg, &lval, i, 0, data))
1763 sprintf(p, "%s%lu", neg ? "-" : "", lval);
1767 if(copy_to_user(s, buf, len))
1774 if (!write && !first && left) {
1775 if(put_user('\n', s))
1782 if (get_user(c, s++))
1798 * proc_dointvec - read a vector of integers
1799 * @table: the sysctl table
1800 * @write: %TRUE if this is a write to the sysctl file
1801 * @filp: the file structure
1802 * @buffer: the user buffer
1803 * @lenp: the size of the user buffer
1804 * @ppos: file position
1806 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1807 * values from/to the user buffer, treated as an ASCII string.
1809 * Returns 0 on success.
1811 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1812 void __user *buffer, size_t *lenp, loff_t *ppos)
1814 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1824 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1826 int write, void *data)
1828 int op = *(int *)data;
1830 int val = *negp ? -*lvalp : *lvalp;
1832 case OP_SET: *valp = val; break;
1833 case OP_AND: *valp &= val; break;
1834 case OP_OR: *valp |= val; break;
1835 case OP_MAX: if(*valp < val)
1838 case OP_MIN: if(*valp > val)
1846 *lvalp = (unsigned long)-val;
1849 *lvalp = (unsigned long)val;
1856 * init may raise the set.
1859 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1860 void __user *buffer, size_t *lenp, loff_t *ppos)
1864 if (!capable(CAP_SYS_MODULE)) {
1868 op = (current->pid == 1) ? OP_SET : OP_AND;
1869 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1870 do_proc_dointvec_bset_conv,&op);
1873 struct do_proc_dointvec_minmax_conv_param {
1878 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1880 int write, void *data)
1882 struct do_proc_dointvec_minmax_conv_param *param = data;
1884 int val = *negp ? -*lvalp : *lvalp;
1885 if ((param->min && *param->min > val) ||
1886 (param->max && *param->max < val))
1893 *lvalp = (unsigned long)-val;
1896 *lvalp = (unsigned long)val;
1903 * proc_dointvec_minmax - read a vector of integers with min/max values
1904 * @table: the sysctl table
1905 * @write: %TRUE if this is a write to the sysctl file
1906 * @filp: the file structure
1907 * @buffer: the user buffer
1908 * @lenp: the size of the user buffer
1909 * @ppos: file position
1911 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1912 * values from/to the user buffer, treated as an ASCII string.
1914 * This routine will ensure the values are within the range specified by
1915 * table->extra1 (min) and table->extra2 (max).
1917 * Returns 0 on success.
1919 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1920 void __user *buffer, size_t *lenp, loff_t *ppos)
1922 struct do_proc_dointvec_minmax_conv_param param = {
1923 .min = (int *) table->extra1,
1924 .max = (int *) table->extra2,
1926 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1927 do_proc_dointvec_minmax_conv, ¶m);
1930 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1932 void __user *buffer,
1933 size_t *lenp, loff_t *ppos,
1934 unsigned long convmul,
1935 unsigned long convdiv)
1937 #define TMPBUFLEN 21
1938 unsigned long *i, *min, *max, val;
1939 int vleft, first=1, neg;
1941 char buf[TMPBUFLEN], *p;
1942 char __user *s = buffer;
1944 if (!table->data || !table->maxlen || !*lenp ||
1945 (*ppos && !write)) {
1950 i = (unsigned long *) table->data;
1951 min = (unsigned long *) table->extra1;
1952 max = (unsigned long *) table->extra2;
1953 vleft = table->maxlen / sizeof(unsigned long);
1956 for (; left && vleft--; i++, min++, max++, first=0) {
1971 if (len > TMPBUFLEN-1)
1973 if (copy_from_user(buf, s, len))
1977 if (*p == '-' && left > 1) {
1981 if (*p < '0' || *p > '9')
1983 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1985 if ((len < left) && *p && !isspace(*p))
1994 if ((min && val < *min) || (max && val > *max))
2001 sprintf(p, "%lu", convdiv * (*i) / convmul);
2005 if(copy_to_user(s, buf, len))
2012 if (!write && !first && left) {
2013 if(put_user('\n', s))
2020 if (get_user(c, s++))
2036 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2037 * @table: the sysctl table
2038 * @write: %TRUE if this is a write to the sysctl file
2039 * @filp: the file structure
2040 * @buffer: the user buffer
2041 * @lenp: the size of the user buffer
2042 * @ppos: file position
2044 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2045 * values from/to the user buffer, treated as an ASCII string.
2047 * This routine will ensure the values are within the range specified by
2048 * table->extra1 (min) and table->extra2 (max).
2050 * Returns 0 on success.
2052 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2053 void __user *buffer, size_t *lenp, loff_t *ppos)
2055 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2059 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2060 * @table: the sysctl table
2061 * @write: %TRUE if this is a write to the sysctl file
2062 * @filp: the file structure
2063 * @buffer: the user buffer
2064 * @lenp: the size of the user buffer
2065 * @ppos: file position
2067 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2068 * values from/to the user buffer, treated as an ASCII string. The values
2069 * are treated as milliseconds, and converted to jiffies when they are stored.
2071 * This routine will ensure the values are within the range specified by
2072 * table->extra1 (min) and table->extra2 (max).
2074 * Returns 0 on success.
2076 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2078 void __user *buffer,
2079 size_t *lenp, loff_t *ppos)
2081 return do_proc_doulongvec_minmax(table, write, filp, buffer,
2082 lenp, ppos, HZ, 1000l);
2086 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2088 int write, void *data)
2091 if (*lvalp > LONG_MAX / HZ)
2093 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2099 lval = (unsigned long)-val;
2102 lval = (unsigned long)val;
2109 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2111 int write, void *data)
2114 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2116 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2122 lval = (unsigned long)-val;
2125 lval = (unsigned long)val;
2127 *lvalp = jiffies_to_clock_t(lval);
2132 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2134 int write, void *data)
2137 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2143 lval = (unsigned long)-val;
2146 lval = (unsigned long)val;
2148 *lvalp = jiffies_to_msecs(lval);
2154 * proc_dointvec_jiffies - read a vector of integers as seconds
2155 * @table: the sysctl table
2156 * @write: %TRUE if this is a write to the sysctl file
2157 * @filp: the file structure
2158 * @buffer: the user buffer
2159 * @lenp: the size of the user buffer
2160 * @ppos: file position
2162 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2163 * values from/to the user buffer, treated as an ASCII string.
2164 * The values read are assumed to be in seconds, and are converted into
2167 * Returns 0 on success.
2169 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2170 void __user *buffer, size_t *lenp, loff_t *ppos)
2172 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2173 do_proc_dointvec_jiffies_conv,NULL);
2177 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2178 * @table: the sysctl table
2179 * @write: %TRUE if this is a write to the sysctl file
2180 * @filp: the file structure
2181 * @buffer: the user buffer
2182 * @lenp: the size of the user buffer
2183 * @ppos: pointer to the file position
2185 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2186 * values from/to the user buffer, treated as an ASCII string.
2187 * The values read are assumed to be in 1/USER_HZ seconds, and
2188 * are converted into jiffies.
2190 * Returns 0 on success.
2192 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2193 void __user *buffer, size_t *lenp, loff_t *ppos)
2195 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2196 do_proc_dointvec_userhz_jiffies_conv,NULL);
2200 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2201 * @table: the sysctl table
2202 * @write: %TRUE if this is a write to the sysctl file
2203 * @filp: the file structure
2204 * @buffer: the user buffer
2205 * @lenp: the size of the user buffer
2206 * @ppos: file position
2207 * @ppos: the current position in the file
2209 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2210 * values from/to the user buffer, treated as an ASCII string.
2211 * The values read are assumed to be in 1/1000 seconds, and
2212 * are converted into jiffies.
2214 * Returns 0 on success.
2216 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2217 void __user *buffer, size_t *lenp, loff_t *ppos)
2219 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2220 do_proc_dointvec_ms_jiffies_conv, NULL);
2223 #else /* CONFIG_PROC_FS */
2225 int proc_dostring(ctl_table *table, int write, struct file *filp,
2226 void __user *buffer, size_t *lenp, loff_t *ppos)
2231 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
2232 void __user *buffer, size_t *lenp, loff_t *ppos)
2237 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2238 void __user *buffer, size_t *lenp, loff_t *ppos)
2243 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2244 void __user *buffer, size_t *lenp, loff_t *ppos)
2249 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2250 void __user *buffer, size_t *lenp, loff_t *ppos)
2255 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2256 void __user *buffer, size_t *lenp, loff_t *ppos)
2261 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2262 void __user *buffer, size_t *lenp, loff_t *ppos)
2267 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2268 void __user *buffer, size_t *lenp, loff_t *ppos)
2273 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2274 void __user *buffer, size_t *lenp, loff_t *ppos)
2279 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2281 void __user *buffer,
2282 size_t *lenp, loff_t *ppos)
2288 #endif /* CONFIG_PROC_FS */
2292 * General sysctl support routines
2295 /* The generic string strategy routine: */
2296 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2297 void __user *oldval, size_t __user *oldlenp,
2298 void __user *newval, size_t newlen, void **context)
2300 if (!table->data || !table->maxlen)
2303 if (oldval && oldlenp) {
2305 if (get_user(bufsize, oldlenp))
2308 size_t len = strlen(table->data), copied;
2310 /* This shouldn't trigger for a well-formed sysctl */
2311 if (len > table->maxlen)
2312 len = table->maxlen;
2314 /* Copy up to a max of bufsize-1 bytes of the string */
2315 copied = (len >= bufsize) ? bufsize - 1 : len;
2317 if (copy_to_user(oldval, table->data, copied) ||
2318 put_user(0, (char __user *)(oldval + copied)))
2320 if (put_user(len, oldlenp))
2324 if (newval && newlen) {
2325 size_t len = newlen;
2326 if (len > table->maxlen)
2327 len = table->maxlen;
2328 if(copy_from_user(table->data, newval, len))
2330 if (len == table->maxlen)
2332 ((char *) table->data)[len] = 0;
2338 * This function makes sure that all of the integers in the vector
2339 * are between the minimum and maximum values given in the arrays
2340 * table->extra1 and table->extra2, respectively.
2342 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2343 void __user *oldval, size_t __user *oldlenp,
2344 void __user *newval, size_t newlen, void **context)
2347 if (newval && newlen) {
2348 int __user *vec = (int __user *) newval;
2349 int *min = (int *) table->extra1;
2350 int *max = (int *) table->extra2;
2354 if (newlen % sizeof(int) != 0)
2357 if (!table->extra1 && !table->extra2)
2360 if (newlen > table->maxlen)
2361 newlen = table->maxlen;
2362 length = newlen / sizeof(int);
2364 for (i = 0; i < length; i++) {
2366 if (get_user(value, vec + i))
2368 if (min && value < min[i])
2370 if (max && value > max[i])
2377 /* Strategy function to convert jiffies to seconds */
2378 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2379 void __user *oldval, size_t __user *oldlenp,
2380 void __user *newval, size_t newlen, void **context)
2385 if (get_user(olen, oldlenp))
2387 if (olen!=sizeof(int))
2390 if (put_user(*(int *)(table->data)/HZ, (int __user *)oldval) ||
2391 (oldlenp && put_user(sizeof(int),oldlenp)))
2394 if (newval && newlen) {
2396 if (newlen != sizeof(int))
2398 if (get_user(new, (int __user *)newval))
2400 *(int *)(table->data) = new*HZ;
2405 /* Strategy function to convert jiffies to seconds */
2406 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2407 void __user *oldval, size_t __user *oldlenp,
2408 void __user *newval, size_t newlen, void **context)
2413 if (get_user(olen, oldlenp))
2415 if (olen!=sizeof(int))
2418 if (put_user(jiffies_to_msecs(*(int *)(table->data)), (int __user *)oldval) ||
2419 (oldlenp && put_user(sizeof(int),oldlenp)))
2422 if (newval && newlen) {
2424 if (newlen != sizeof(int))
2426 if (get_user(new, (int __user *)newval))
2428 *(int *)(table->data) = msecs_to_jiffies(new);
2433 #else /* CONFIG_SYSCTL */
2436 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2441 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2442 void __user *oldval, size_t __user *oldlenp,
2443 void __user *newval, size_t newlen, void **context)
2448 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2449 void __user *oldval, size_t __user *oldlenp,
2450 void __user *newval, size_t newlen, void **context)
2455 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2456 void __user *oldval, size_t __user *oldlenp,
2457 void __user *newval, size_t newlen, void **context)
2462 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2463 void __user *oldval, size_t __user *oldlenp,
2464 void __user *newval, size_t newlen, void **context)
2469 int proc_dostring(ctl_table *table, int write, struct file *filp,
2470 void __user *buffer, size_t *lenp, loff_t *ppos)
2475 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2476 void __user *buffer, size_t *lenp, loff_t *ppos)
2481 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2482 void __user *buffer, size_t *lenp, loff_t *ppos)
2487 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2488 void __user *buffer, size_t *lenp, loff_t *ppos)
2493 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2494 void __user *buffer, size_t *lenp, loff_t *ppos)
2499 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2500 void __user *buffer, size_t *lenp, loff_t *ppos)
2505 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2506 void __user *buffer, size_t *lenp, loff_t *ppos)
2511 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2512 void __user *buffer, size_t *lenp, loff_t *ppos)
2517 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2519 void __user *buffer,
2520 size_t *lenp, loff_t *ppos)
2525 struct ctl_table_header * register_sysctl_table(ctl_table * table,
2531 void unregister_sysctl_table(struct ctl_table_header * table)
2535 #endif /* CONFIG_SYSCTL */
2538 * No sense putting this after each symbol definition, twice,
2539 * exception granted :-)
2541 EXPORT_SYMBOL(proc_dointvec);
2542 EXPORT_SYMBOL(proc_dointvec_jiffies);
2543 EXPORT_SYMBOL(proc_dointvec_minmax);
2544 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2545 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2546 EXPORT_SYMBOL(proc_dostring);
2547 EXPORT_SYMBOL(proc_doulongvec_minmax);
2548 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2549 EXPORT_SYMBOL(register_sysctl_table);
2550 EXPORT_SYMBOL(sysctl_intvec);
2551 EXPORT_SYMBOL(sysctl_jiffies);
2552 EXPORT_SYMBOL(sysctl_ms_jiffies);
2553 EXPORT_SYMBOL(sysctl_string);
2554 EXPORT_SYMBOL(unregister_sysctl_table);