kernel/sysctl.c

   1 /*
   2  * sysctl.c: General linux system control interface
   3  *
   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
  12  *  Horn.
  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
  16  *  Wendling.
  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
  19  */
  20
  21 #include <linux/config.h>
  22 #include <linux/module.h>
  23 #include <linux/mm.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/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/sysrq.h>
  35 #include <linux/highuid.h>
  36 #include <linux/writeback.h>
  37 #include <linux/hugetlb.h>
  38 #include <linux/security.h>
  39 #include <linux/initrd.h>
  40 #include <linux/times.h>
  41 #include <linux/limits.h>
  42 #include <asm/uaccess.h>
  43
  44 #ifdef CONFIG_ROOT_NFS
  45 #include <linux/nfs_fs.h>
  46 #endif
  47
  48 #if defined(CONFIG_SYSCTL)
  49
  50 /* External variables not in a header file. */
  51 extern int panic_timeout;
  52 extern int C_A_D;
  53 extern int sysctl_overcommit_memory;
  54 extern int sysctl_overcommit_ratio;
  55 extern int max_threads;
  56 extern atomic_t nr_queued_signals;
  57 extern int max_queued_signals;
  58 extern int sysrq_enabled;
  59 extern int core_uses_pid;
  60 extern char core_pattern[];
  61 extern int cad_pid;
  62 extern int pid_max;
  63 extern int sysctl_lower_zone_protection;
  64 extern int min_free_kbytes;
  65 extern int printk_ratelimit_jiffies;
  66 extern int printk_ratelimit_burst;
  67
  68 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
  69 static int maxolduid = 65535;
  70 static int minolduid;
  71
  72 static int ngroups_max = NGROUPS_MAX;
  73
  74 #ifdef CONFIG_KMOD
  75 extern char modprobe_path[];
  76 #endif
  77 #ifdef CONFIG_HOTPLUG
  78 extern char hotplug_path[];
  79 #endif
  80 #ifdef CONFIG_CHR_DEV_SG
  81 extern int sg_big_buff;
  82 #endif
  83 #ifdef CONFIG_SYSVIPC
  84 extern size_t shm_ctlmax;
  85 extern size_t shm_ctlall;
  86 extern int shm_ctlmni;
  87 extern int msg_ctlmax;
  88 extern int msg_ctlmnb;
  89 extern int msg_ctlmni;
  90 extern int sem_ctls[];
  91 #endif
  92
  93 #ifdef __sparc__
  94 extern char reboot_command [];
  95 extern int stop_a_enabled;
  96 extern int scons_pwroff;
  97 #endif
  98
  99 #ifdef __hppa__
 100 extern int pwrsw_enabled;
 101 extern int unaligned_enabled;
 102 #endif
 103
 104 #ifdef CONFIG_ARCH_S390
 105 #ifdef CONFIG_MATHEMU
 106 extern int sysctl_ieee_emulation_warnings;
 107 #endif
 108 extern int sysctl_userprocess_debug;
 109 #endif
 110
 111 extern int sysctl_hz_timer;
 112
 113 #if defined(CONFIG_PPC32) && defined(CONFIG_6xx)
 114 extern unsigned long powersave_nap;
 115 int proc_dol2crvec(ctl_table *table, int write, struct file *filp,
 116                   void *buffer, size_t *lenp);
 117 #endif
 118
 119 #ifdef CONFIG_BSD_PROCESS_ACCT
 120 extern int acct_parm[];
 121 #endif
 122
 123 static int parse_table(int __user *, int, void __user *, size_t __user *, void __user *, size_t,
 124                        ctl_table *, void **);
 125 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
 126                   void __user *buffer, size_t *lenp);
 127
 128 static ctl_table root_table[];
 129 static struct ctl_table_header root_table_header =
 130         { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
 131
 132 static ctl_table kern_table[];
 133 static ctl_table vm_table[];
 134 #ifdef CONFIG_NET
 135 extern ctl_table net_table[];
 136 #endif
 137 static ctl_table proc_table[];
 138 static ctl_table fs_table[];
 139 static ctl_table debug_table[];
 140 static ctl_table dev_table[];
 141 extern ctl_table random_table[];
 142 #ifdef CONFIG_UNIX98_PTYS
 143 extern ctl_table pty_table[];
 144 #endif
 145
 146 /* /proc declarations: */
 147
 148 #ifdef CONFIG_PROC_FS
 149
 150 static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
 151 static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
 152 static int proc_opensys(struct inode *, struct file *);
 153
 154 struct file_operations proc_sys_file_operations = {
 155         .open           = proc_opensys,
 156         .read           = proc_readsys,
 157         .write          = proc_writesys,
 158 };
 159
 160 extern struct proc_dir_entry *proc_sys_root;
 161
 162 static void register_proc_table(ctl_table *, struct proc_dir_entry *);
 163 static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
 164 #endif
 165
 166 /* The default sysctl tables: */
 167
 168 static ctl_table root_table[] = {
 169         {
 170                 .ctl_name       = CTL_KERN,
 171                 .procname       = "kernel",
 172                 .mode           = 0555,
 173                 .child          = kern_table,
 174         },
 175         {
 176                 .ctl_name       = CTL_VM,
 177                 .procname       = "vm",
 178                 .mode           = 0555,
 179                 .child          = vm_table,
 180         },
 181 #ifdef CONFIG_NET
 182         {
 183                 .ctl_name       = CTL_NET,
 184                 .procname       = "net",
 185                 .mode           = 0555,
 186                 .child          = net_table,
 187         },
 188 #endif
 189         {
 190                 .ctl_name       = CTL_PROC,
 191                 .procname       = "proc",
 192                 .mode           = 0555,
 193                 .child          = proc_table,
 194         },
 195         {
 196                 .ctl_name       = CTL_FS,
 197                 .procname       = "fs",
 198                 .mode           = 0555,
 199                 .child          = fs_table,
 200         },
 201         {
 202                 .ctl_name       = CTL_DEBUG,
 203                 .procname       = "debug",
 204                 .mode           = 0555,
 205                 .child          = debug_table,
 206         },
 207         {
 208                 .ctl_name       = CTL_DEV,
 209                 .procname       = "dev",
 210                 .mode           = 0555,
 211                 .child          = dev_table,
 212         },
 213         { .ctl_name = 0 }
 214 };
 215
 216 static ctl_table kern_table[] = {
 217         {
 218                 .ctl_name       = KERN_OSTYPE,
 219                 .procname       = "ostype",
 220                 .data           = system_utsname.sysname,
 221                 .maxlen         = sizeof(system_utsname.sysname),
 222                 .mode           = 0444,
 223                 .proc_handler   = &proc_doutsstring,
 224                 .strategy       = &sysctl_string,
 225         },
 226         {
 227                 .ctl_name       = KERN_OSRELEASE,
 228                 .procname       = "osrelease",
 229                 .data           = system_utsname.release,
 230                 .maxlen         = sizeof(system_utsname.release),
 231                 .mode           = 0444,
 232                 .proc_handler   = &proc_doutsstring,
 233                 .strategy       = &sysctl_string,
 234         },
 235         {
 236                 .ctl_name       = KERN_VERSION,
 237                 .procname       = "version",
 238                 .data           = system_utsname.version,
 239                 .maxlen         = sizeof(system_utsname.version),
 240                 .mode           = 0444,
 241                 .proc_handler   = &proc_doutsstring,
 242                 .strategy       = &sysctl_string,
 243         },
 244         {
 245                 .ctl_name       = KERN_NODENAME,
 246                 .procname       = "hostname",
 247                 .data           = system_utsname.nodename,
 248                 .maxlen         = sizeof(system_utsname.nodename),
 249                 .mode           = 0644,
 250                 .proc_handler   = &proc_doutsstring,
 251                 .strategy       = &sysctl_string,
 252         },
 253         {
 254                 .ctl_name       = KERN_DOMAINNAME,
 255                 .procname       = "domainname",
 256                 .data           = system_utsname.domainname,
 257                 .maxlen         = sizeof(system_utsname.domainname),
 258                 .mode           = 0644,
 259                 .proc_handler   = &proc_doutsstring,
 260                 .strategy       = &sysctl_string,
 261         },
 262         {
 263                 .ctl_name       = KERN_PANIC,
 264                 .procname       = "panic",
 265                 .data           = &panic_timeout,
 266                 .maxlen         = sizeof(int),
 267                 .mode           = 0644,
 268                 .proc_handler   = &proc_dointvec,
 269         },
 270         {
 271                 .ctl_name       = KERN_CORE_USES_PID,
 272                 .procname       = "core_uses_pid",
 273                 .data           = &core_uses_pid,
 274                 .maxlen         = sizeof(int),
 275                 .mode           = 0644,
 276                 .proc_handler   = &proc_dointvec,
 277         },
 278         {
 279                 .ctl_name       = KERN_CORE_PATTERN,
 280                 .procname       = "core_pattern",
 281                 .data           = core_pattern,
 282                 .maxlen         = 64,
 283                 .mode           = 0644,
 284                 .proc_handler   = &proc_dostring,
 285                 .strategy       = &sysctl_string,
 286         },
 287         {
 288                 .ctl_name       = KERN_TAINTED,
 289                 .procname       = "tainted",
 290                 .data           = &tainted,
 291                 .maxlen         = sizeof(int),
 292                 .mode           = 0644,
 293                 .proc_handler   = &proc_dointvec,
 294         },
 295         {
 296                 .ctl_name       = KERN_CAP_BSET,
 297                 .procname       = "cap-bound",
 298                 .data           = &cap_bset,
 299                 .maxlen         = sizeof(kernel_cap_t),
 300                 .mode           = 0600,
 301                 .proc_handler   = &proc_dointvec_bset,
 302         },
 303 #ifdef CONFIG_BLK_DEV_INITRD
 304         {
 305                 .ctl_name       = KERN_REALROOTDEV,
 306                 .procname       = "real-root-dev",
 307                 .data           = &real_root_dev,
 308                 .maxlen         = sizeof(int),
 309                 .mode           = 0644,
 310                 .proc_handler   = &proc_dointvec,
 311         },
 312 #endif
 313 #ifdef __sparc__
 314         {
 315                 .ctl_name       = KERN_SPARC_REBOOT,
 316                 .procname       = "reboot-cmd",
 317                 .data           = reboot_command,
 318                 .maxlen         = 256,
 319                 .mode           = 0644,
 320                 .proc_handler   = &proc_dostring,
 321                 .strategy       = &sysctl_string,
 322         },
 323         {
 324                 .ctl_name       = KERN_SPARC_STOP_A,
 325                 .procname       = "stop-a",
 326                 .data           = &stop_a_enabled,
 327                 .maxlen         = sizeof (int),
 328                 .mode           = 0644,
 329                 .proc_handler   = &proc_dointvec,
 330         },
 331         {
 332                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 333                 .procname       = "scons-poweroff",
 334                 .data           = &scons_pwroff,
 335                 .maxlen         = sizeof (int),
 336                 .mode           = 0644,
 337                 .proc_handler   = &proc_dointvec,
 338         },
 339 #endif
 340 #ifdef __hppa__
 341         {
 342                 .ctl_name       = KERN_HPPA_PWRSW,
 343                 .procname       = "soft-power",
 344                 .data           = &pwrsw_enabled,
 345                 .maxlen         = sizeof (int),
 346                 .mode           = 0644,
 347                 .proc_handler   = &proc_dointvec,
 348         },
 349         {
 350                 .ctl_name       = KERN_HPPA_UNALIGNED,
 351                 .procname       = "unaligned-trap",
 352                 .data           = &unaligned_enabled,
 353                 .maxlen         = sizeof (int),
 354                 .mode           = 0644,
 355                 .proc_handler   = &proc_dointvec,
 356         },
 357 #endif
 358 #if defined(CONFIG_PPC32) && defined(CONFIG_6xx)
 359         {
 360                 .ctl_name       = KERN_PPC_POWERSAVE_NAP,
 361                 .procname       = "powersave-nap",
 362                 .data           = &powersave_nap,
 363                 .maxlen         = sizeof(int),
 364                 .mode           = 0644,
 365                 .proc_handler   = &proc_dointvec,
 366         },
 367         {
 368                 .ctl_name       = KERN_PPC_L2CR,
 369                 .procname       = "l2cr",
 370                 .mode           = 0644,
 371                 .proc_handler   = &proc_dol2crvec,
 372         },
 373 #endif
 374         {
 375                 .ctl_name       = KERN_CTLALTDEL,
 376                 .procname       = "ctrl-alt-del",
 377                 .data           = &C_A_D,
 378                 .maxlen         = sizeof(int),
 379                 .mode           = 0644,
 380                 .proc_handler   = &proc_dointvec,
 381         },
 382         {
 383                 .ctl_name       = KERN_PRINTK,
 384                 .procname       = "printk",
 385                 .data           = &console_loglevel,
 386                 .maxlen         = 4*sizeof(int),
 387                 .mode           = 0644,
 388                 .proc_handler   = &proc_dointvec,
 389         },
 390 #ifdef CONFIG_KMOD
 391         {
 392                 .ctl_name       = KERN_MODPROBE,
 393                 .procname       = "modprobe",
 394                 .data           = &modprobe_path,
 395                 .maxlen         = KMOD_PATH_LEN,
 396                 .mode           = 0644,
 397                 .proc_handler   = &proc_dostring,
 398                 .strategy       = &sysctl_string,
 399         },
 400 #endif
 401 #ifdef CONFIG_HOTPLUG
 402         {
 403                 .ctl_name       = KERN_HOTPLUG,
 404                 .procname       = "hotplug",
 405                 .data           = &hotplug_path,
 406                 .maxlen         = KMOD_PATH_LEN,
 407                 .mode           = 0644,
 408                 .proc_handler   = &proc_dostring,
 409                 .strategy       = &sysctl_string,
 410         },
 411 #endif
 412 #ifdef CONFIG_CHR_DEV_SG
 413         {
 414                 .ctl_name       = KERN_SG_BIG_BUFF,
 415                 .procname       = "sg-big-buff",
 416                 .data           = &sg_big_buff,
 417                 .maxlen         = sizeof (int),
 418                 .mode           = 0444,
 419                 .proc_handler   = &proc_dointvec,
 420         },
 421 #endif
 422 #ifdef CONFIG_BSD_PROCESS_ACCT
 423         {
 424                 .ctl_name       = KERN_ACCT,
 425                 .procname       = "acct",
 426                 .data           = &acct_parm,
 427                 .maxlen         = 3*sizeof(int),
 428                 .mode           = 0644,
 429                 .proc_handler   = &proc_dointvec,
 430         },
 431 #endif
 432         {
 433                 .ctl_name       = KERN_RTSIGNR,
 434                 .procname       = "rtsig-nr",
 435                 .data           = &nr_queued_signals,
 436                 .maxlen         = sizeof(int),
 437                 .mode           = 0444,
 438                 .proc_handler   = &proc_dointvec,
 439         },
 440         {
 441                 .ctl_name       = KERN_RTSIGMAX,
 442                 .procname       = "rtsig-max",
 443                 .data           = &max_queued_signals,
 444                 .maxlen         = sizeof(int),
 445                 .mode           = 0644,
 446                 .proc_handler   = &proc_dointvec,
 447         },
 448 #ifdef CONFIG_SYSVIPC
 449         {
 450                 .ctl_name       = KERN_SHMMAX,
 451                 .procname       = "shmmax",
 452                 .data           = &shm_ctlmax,
 453                 .maxlen         = sizeof (size_t),
 454                 .mode           = 0644,
 455                 .proc_handler   = &proc_doulongvec_minmax,
 456         },
 457         {
 458                 .ctl_name       = KERN_SHMALL,
 459                 .procname       = "shmall",
 460                 .data           = &shm_ctlall,
 461                 .maxlen         = sizeof (size_t),
 462                 .mode           = 0644,
 463                 .proc_handler   = &proc_doulongvec_minmax,
 464         },
 465         {
 466                 .ctl_name       = KERN_SHMMNI,
 467                 .procname       = "shmmni",
 468                 .data           = &shm_ctlmni,
 469                 .maxlen         = sizeof (int),
 470                 .mode           = 0644,
 471                 .proc_handler   = &proc_dointvec,
 472         },
 473         {
 474                 .ctl_name       = KERN_MSGMAX,
 475                 .procname       = "msgmax",
 476                 .data           = &msg_ctlmax,
 477                 .maxlen         = sizeof (int),
 478                 .mode           = 0644,
 479                 .proc_handler   = &proc_dointvec,
 480         },
 481         {
 482                 .ctl_name       = KERN_MSGMNI,
 483                 .procname       = "msgmni",
 484                 .data           = &msg_ctlmni,
 485                 .maxlen         = sizeof (int),
 486                 .mode           = 0644,
 487                 .proc_handler   = &proc_dointvec,
 488         },
 489         {
 490                 .ctl_name       = KERN_MSGMNB,
 491                 .procname       =  "msgmnb",
 492                 .data           = &msg_ctlmnb,
 493                 .maxlen         = sizeof (int),
 494                 .mode           = 0644,
 495                 .proc_handler   = &proc_dointvec,
 496         },
 497         {
 498                 .ctl_name       = KERN_SEM,
 499                 .procname       = "sem",
 500                 .data           = &sem_ctls,
 501                 .maxlen         = 4*sizeof (int),
 502                 .mode           = 0644,
 503                 .proc_handler   = &proc_dointvec,
 504         },
 505 #endif
 506 #ifdef CONFIG_MAGIC_SYSRQ
 507         {
 508                 .ctl_name       = KERN_SYSRQ,
 509                 .procname       = "sysrq",
 510                 .data           = &sysrq_enabled,
 511                 .maxlen         = sizeof (int),
 512                 .mode           = 0644,
 513                 .proc_handler   = &proc_dointvec,
 514         },
 515 #endif
 516         {
 517                 .ctl_name       = KERN_CADPID,
 518                 .procname       = "cad_pid",
 519                 .data           = &cad_pid,
 520                 .maxlen         = sizeof (int),
 521                 .mode           = 0600,
 522                 .proc_handler   = &proc_dointvec,
 523         },
 524         {
 525                 .ctl_name       = KERN_MAX_THREADS,
 526                 .procname       = "threads-max",
 527                 .data           = &max_threads,
 528                 .maxlen         = sizeof(int),
 529                 .mode           = 0644,
 530                 .proc_handler   = &proc_dointvec,
 531         },
 532         {
 533                 .ctl_name       = KERN_RANDOM,
 534                 .procname       = "random",
 535                 .mode           = 0555,
 536                 .child          = random_table,
 537         },
 538 #ifdef CONFIG_UNIX98_PTYS
 539         {
 540                 .ctl_name       = KERN_PTY,
 541                 .procname       = "pty",
 542                 .mode           = 0555,
 543                 .child          = pty_table,
 544         },
 545 #endif
 546         {
 547                 .ctl_name       = KERN_OVERFLOWUID,
 548                 .procname       = "overflowuid",
 549                 .data           = &overflowuid,
 550                 .maxlen         = sizeof(int),
 551                 .mode           = 0644,
 552                 .proc_handler   = &proc_dointvec_minmax,
 553                 .strategy       = &sysctl_intvec,
 554                 .extra1         = &minolduid,
 555                 .extra2         = &maxolduid,
 556         },
 557         {
 558                 .ctl_name       = KERN_OVERFLOWGID,
 559                 .procname       = "overflowgid",
 560                 .data           = &overflowgid,
 561                 .maxlen         = sizeof(int),
 562                 .mode           = 0644,
 563                 .proc_handler   = &proc_dointvec_minmax,
 564                 .strategy       = &sysctl_intvec,
 565                 .extra1         = &minolduid,
 566                 .extra2         = &maxolduid,
 567         },
 568 #ifdef CONFIG_ARCH_S390
 569 #ifdef CONFIG_MATHEMU
 570         {
 571                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 572                 .procname       = "ieee_emulation_warnings",
 573                 .data           = &sysctl_ieee_emulation_warnings,
 574                 .maxlen         = sizeof(int),
 575                 .mode           = 0644,
 576                 .proc_handler   = &proc_dointvec,
 577         },
 578 #endif
 579 #ifdef CONFIG_NO_IDLE_HZ
 580         {
 581                 .ctl_name       = KERN_HZ_TIMER,
 582                 .procname       = "hz_timer",
 583                 .data           = &sysctl_hz_timer,
 584                 .maxlen         = sizeof(int),
 585                 .mode           = 0644,
 586                 .proc_handler   = &proc_dointvec,
 587         },
 588 #endif
 589         {
 590                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 591                 .procname       = "userprocess_debug",
 592                 .data           = &sysctl_userprocess_debug,
 593                 .maxlen         = sizeof(int),
 594                 .mode           = 0644,
 595                 .proc_handler   = &proc_dointvec,
 596         },
 597 #endif
 598         {
 599                 .ctl_name       = KERN_PIDMAX,
 600                 .procname       = "pid_max",
 601                 .data           = &pid_max,
 602                 .maxlen         = sizeof (int),
 603                 .mode           = 0644,
 604                 .proc_handler   = &proc_dointvec,
 605         },
 606         {
 607                 .ctl_name       = KERN_PANIC_ON_OOPS,
 608                 .procname       = "panic_on_oops",
 609                 .data           = &panic_on_oops,
 610                 .maxlen         = sizeof(int),
 611                 .mode           = 0644,
 612                 .proc_handler   = &proc_dointvec,
 613         },
 614         {
 615                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 616                 .procname       = "printk_ratelimit",
 617                 .data           = &printk_ratelimit_jiffies,
 618                 .maxlen         = sizeof(int),
 619                 .mode           = 0644,
 620                 .proc_handler   = &proc_dointvec_jiffies,
 621                 .strategy       = &sysctl_jiffies,
 622         },
 623         {
 624                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 625                 .procname       = "printk_ratelimit_burst",
 626                 .data           = &printk_ratelimit_burst,
 627                 .maxlen         = sizeof(int),
 628                 .mode           = 0644,
 629                 .proc_handler   = &proc_dointvec,
 630         },
 631         {
 632                 .ctl_name       = KERN_NGROUPS_MAX,
 633                 .procname       = "ngroups_max",
 634                 .data           = &ngroups_max,
 635                 .maxlen         = sizeof (int),
 636                 .mode           = 0444,
 637                 .proc_handler   = &proc_dointvec,
 638         },
 639         { .ctl_name = 0 }
 640 };
 641
 642 /* Constants for minimum and maximum testing in vm_table.
 643    We use these as one-element integer vectors. */
 644 static int zero;
 645 static int one_hundred = 100;
 646
 647
 648 static ctl_table vm_table[] = {
 649         {
 650                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
 651                 .procname       = "overcommit_memory",
 652                 .data           = &sysctl_overcommit_memory,
 653                 .maxlen         = sizeof(sysctl_overcommit_memory),
 654                 .mode           = 0644,
 655                 .proc_handler   = &proc_dointvec,
 656         },
 657         {
 658                 .ctl_name       = VM_OVERCOMMIT_RATIO,
 659                 .procname       = "overcommit_ratio",
 660                 .data           = &sysctl_overcommit_ratio,
 661                 .maxlen         = sizeof(sysctl_overcommit_ratio),
 662                 .mode           = 0644,
 663                 .proc_handler   = &proc_dointvec,
 664         },
 665         {
 666                 .ctl_name       = VM_PAGE_CLUSTER,
 667                 .procname       = "page-cluster",
 668                 .data           = &page_cluster,
 669                 .maxlen         = sizeof(int),
 670                 .mode           = 0644,
 671                 .proc_handler   = &proc_dointvec,
 672         },
 673         {
 674                 .ctl_name       = VM_DIRTY_BACKGROUND,
 675                 .procname       = "dirty_background_ratio",
 676                 .data           = &dirty_background_ratio,
 677                 .maxlen         = sizeof(dirty_background_ratio),
 678                 .mode           = 0644,
 679                 .proc_handler   = &proc_dointvec_minmax,
 680                 .strategy       = &sysctl_intvec,
 681                 .extra1         = &zero,
 682                 .extra2         = &one_hundred,
 683         },
 684         {
 685                 .ctl_name       = VM_DIRTY_RATIO,
 686                 .procname       = "dirty_ratio",
 687                 .data           = &vm_dirty_ratio,
 688                 .maxlen         = sizeof(vm_dirty_ratio),
 689                 .mode           = 0644,
 690                 .proc_handler   = &proc_dointvec_minmax,
 691                 .strategy       = &sysctl_intvec,
 692                 .extra1         = &zero,
 693                 .extra2         = &one_hundred,
 694         },
 695         {
 696                 .ctl_name       = VM_DIRTY_WB_CS,
 697                 .procname       = "dirty_writeback_centisecs",
 698                 .data           = &dirty_writeback_centisecs,
 699                 .maxlen         = sizeof(dirty_writeback_centisecs),
 700                 .mode           = 0644,
 701                 .proc_handler   = &dirty_writeback_centisecs_handler,
 702         },
 703         {
 704                 .ctl_name       = VM_DIRTY_EXPIRE_CS,
 705                 .procname       = "dirty_expire_centisecs",
 706                 .data           = &dirty_expire_centisecs,
 707                 .maxlen         = sizeof(dirty_expire_centisecs),
 708                 .mode           = 0644,
 709                 .proc_handler   = &proc_dointvec,
 710         },
 711         {
 712                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
 713                 .procname       = "nr_pdflush_threads",
 714                 .data           = &nr_pdflush_threads,
 715                 .maxlen         = sizeof nr_pdflush_threads,
 716                 .mode           = 0444 /* read-only*/,
 717                 .proc_handler   = &proc_dointvec,
 718         },
 719         {
 720                 .ctl_name       = VM_SWAPPINESS,
 721                 .procname       = "swappiness",
 722                 .data           = &vm_swappiness,
 723                 .maxlen         = sizeof(vm_swappiness),
 724                 .mode           = 0644,
 725                 .proc_handler   = &proc_dointvec_minmax,
 726                 .strategy       = &sysctl_intvec,
 727                 .extra1         = &zero,
 728                 .extra2         = &one_hundred,
 729         },
 730 #ifdef CONFIG_HUGETLB_PAGE
 731          {
 732                 .ctl_name       = VM_HUGETLB_PAGES,
 733                 .procname       = "nr_hugepages",
 734                 .data           = &max_huge_pages,
 735                 .maxlen         = sizeof(unsigned long),
 736                 .mode           = 0644,
 737                 .proc_handler   = &hugetlb_sysctl_handler,
 738                 .extra1         = (void *)&hugetlb_zero,
 739                 .extra2         = (void *)&hugetlb_infinity,
 740          },
 741          {
 742                 .ctl_name       = VM_HUGETLB_GROUP,
 743                 .procname       = "hugetlb_shm_group",
 744                 .data           = &sysctl_hugetlb_shm_group,
 745                 .maxlen         = sizeof(gid_t),
 746                 .mode           = 0644,
 747                 .proc_handler   = &proc_dointvec,
 748          },
 749 #endif
 750         {
 751                 .ctl_name       = VM_LOWER_ZONE_PROTECTION,
 752                 .procname       = "lower_zone_protection",
 753                 .data           = &sysctl_lower_zone_protection,
 754                 .maxlen         = sizeof(sysctl_lower_zone_protection),
 755                 .mode           = 0644,
 756                 .proc_handler   = &lower_zone_protection_sysctl_handler,
 757                 .strategy       = &sysctl_intvec,
 758                 .extra1         = &zero,
 759         },
 760         {
 761                 .ctl_name       = VM_MIN_FREE_KBYTES,
 762                 .procname       = "min_free_kbytes",
 763                 .data           = &min_free_kbytes,
 764                 .maxlen         = sizeof(min_free_kbytes),
 765                 .mode           = 0644,
 766                 .proc_handler   = &min_free_kbytes_sysctl_handler,
 767                 .strategy       = &sysctl_intvec,
 768                 .extra1         = &zero,
 769         },
 770         {
 771                 .ctl_name       = VM_MAX_MAP_COUNT,
 772                 .procname       = "max_map_count",
 773                 .data           = &sysctl_max_map_count,
 774                 .maxlen         = sizeof(sysctl_max_map_count),
 775                 .mode           = 0644,
 776                 .proc_handler   = &proc_dointvec
 777         },
 778         {
 779                 .ctl_name       = VM_LAPTOP_MODE,
 780                 .procname       = "laptop_mode",
 781                 .data           = &laptop_mode,
 782                 .maxlen         = sizeof(laptop_mode),
 783                 .mode           = 0644,
 784                 .proc_handler   = &proc_dointvec,
 785                 .strategy       = &sysctl_intvec,
 786                 .extra1         = &zero,
 787         },
 788         {
 789                 .ctl_name       = VM_BLOCK_DUMP,
 790                 .procname       = "block_dump",
 791                 .data           = &block_dump,
 792                 .maxlen         = sizeof(block_dump),
 793                 .mode           = 0644,
 794                 .proc_handler   = &proc_dointvec,
 795                 .strategy       = &sysctl_intvec,
 796                 .extra1         = &zero,
 797         },
 798         { .ctl_name = 0 }
 799 };
 800
 801 static ctl_table proc_table[] = {
 802         { .ctl_name = 0 }
 803 };
 804
 805 static ctl_table fs_table[] = {
 806         {
 807                 .ctl_name       = FS_NRINODE,
 808                 .procname       = "inode-nr",
 809                 .data           = &inodes_stat,
 810                 .maxlen         = 2*sizeof(int),
 811                 .mode           = 0444,
 812                 .proc_handler   = &proc_dointvec,
 813         },
 814         {
 815                 .ctl_name       = FS_STATINODE,
 816                 .procname       = "inode-state",
 817                 .data           = &inodes_stat,
 818                 .maxlen         = 7*sizeof(int),
 819                 .mode           = 0444,
 820                 .proc_handler   = &proc_dointvec,
 821         },
 822         {
 823                 .ctl_name       = FS_NRFILE,
 824                 .procname       = "file-nr",
 825                 .data           = &files_stat,
 826                 .maxlen         = 3*sizeof(int),
 827                 .mode           = 0444,
 828                 .proc_handler   = &proc_dointvec,
 829         },
 830         {
 831                 .ctl_name       = FS_MAXFILE,
 832                 .procname       = "file-max",
 833                 .data           = &files_stat.max_files,
 834                 .maxlen         = sizeof(int),
 835                 .mode           = 0644,
 836                 .proc_handler   = &proc_dointvec,
 837         },
 838         {
 839                 .ctl_name       = FS_DENTRY,
 840                 .procname       = "dentry-state",
 841                 .data           = &dentry_stat,
 842                 .maxlen         = 6*sizeof(int),
 843                 .mode           = 0444,
 844                 .proc_handler   = &proc_dointvec,
 845         },
 846         {
 847                 .ctl_name       = FS_OVERFLOWUID,
 848                 .procname       = "overflowuid",
 849                 .data           = &fs_overflowuid,
 850                 .maxlen         = sizeof(int),
 851                 .mode           = 0644,
 852                 .proc_handler   = &proc_dointvec_minmax,
 853                 .strategy       = &sysctl_intvec,
 854                 .extra1         = &minolduid,
 855                 .extra2         = &maxolduid,
 856         },
 857         {
 858                 .ctl_name       = FS_OVERFLOWGID,
 859                 .procname       = "overflowgid",
 860                 .data           = &fs_overflowgid,
 861                 .maxlen         = sizeof(int),
 862                 .mode           = 0644,
 863                 .proc_handler   = &proc_dointvec_minmax,
 864                 .strategy       = &sysctl_intvec,
 865                 .extra1         = &minolduid,
 866                 .extra2         = &maxolduid,
 867         },
 868         {
 869                 .ctl_name       = FS_LEASES,
 870                 .procname       = "leases-enable",
 871                 .data           = &leases_enable,
 872                 .maxlen         = sizeof(int),
 873                 .mode           = 0644,
 874                 .proc_handler   = &proc_dointvec,
 875         },
 876         {
 877                 .ctl_name       = FS_DIR_NOTIFY,
 878                 .procname       = "dir-notify-enable",
 879                 .data           = &dir_notify_enable,
 880                 .maxlen         = sizeof(int),
 881                 .mode           = 0644,
 882                 .proc_handler   = &proc_dointvec,
 883         },
 884         {
 885                 .ctl_name       = FS_LEASE_TIME,
 886                 .procname       = "lease-break-time",
 887                 .data           = &lease_break_time,
 888                 .maxlen         = sizeof(int),
 889                 .mode           = 0644,
 890                 .proc_handler   = &proc_dointvec,
 891         },
 892         {
 893                 .ctl_name       = FS_AIO_NR,
 894                 .procname       = "aio-nr",
 895                 .data           = &aio_nr,
 896                 .maxlen         = sizeof(aio_nr),
 897                 .mode           = 0444,
 898                 .proc_handler   = &proc_dointvec,
 899         },
 900         {
 901                 .ctl_name       = FS_AIO_MAX_NR,
 902                 .procname       = "aio-max-nr",
 903                 .data           = &aio_max_nr,
 904                 .maxlen         = sizeof(aio_max_nr),
 905                 .mode           = 0644,
 906                 .proc_handler   = &proc_dointvec,
 907         },
 908         { .ctl_name = 0 }
 909 };
 910
 911 static ctl_table debug_table[] = {
 912         { .ctl_name = 0 }
 913 };
 914
 915 static ctl_table dev_table[] = {
 916         { .ctl_name = 0 }
 917 };
 918
 919 extern void init_irq_proc (void);
 920
 921 void __init sysctl_init(void)
 922 {
 923 #ifdef CONFIG_PROC_FS
 924         register_proc_table(root_table, proc_sys_root);
 925         init_irq_proc();
 926 #endif
 927 }
 928
 929 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
 930                void __user *newval, size_t newlen)
 931 {
 932         struct list_head *tmp;
 933
 934         if (nlen <= 0 || nlen >= CTL_MAXNAME)
 935                 return -ENOTDIR;
 936         if (oldval) {
 937                 int old_len;
 938                 if (!oldlenp || get_user(old_len, oldlenp))
 939                         return -EFAULT;
 940         }
 941         tmp = &root_table_header.ctl_entry;
 942         do {
 943                 struct ctl_table_header *head =
 944                         list_entry(tmp, struct ctl_table_header, ctl_entry);
 945                 void *context = NULL;
 946                 int error = parse_table(name, nlen, oldval, oldlenp,
 947                                         newval, newlen, head->ctl_table,
 948                                         &context);
 949                 if (context)
 950                         kfree(context);
 951                 if (error != -ENOTDIR)
 952                         return error;
 953                 tmp = tmp->next;
 954         } while (tmp != &root_table_header.ctl_entry);
 955         return -ENOTDIR;
 956 }
 957
 958 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
 959 {
 960         struct __sysctl_args tmp;
 961         int error;
 962
 963         if (copy_from_user(&tmp, args, sizeof(tmp)))
 964                 return -EFAULT;
 965
 966         lock_kernel();
 967         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
 968                           tmp.newval, tmp.newlen);
 969         unlock_kernel();
 970         return error;
 971 }
 972
 973 /*
 974  * ctl_perm does NOT grant the superuser all rights automatically, because
 975  * some sysctl variables are readonly even to root.
 976  */
 977
 978 static int test_perm(int mode, int op)
 979 {
 980         if (!current->euid)
 981                 mode >>= 6;
 982         else if (in_egroup_p(0))
 983                 mode >>= 3;
 984         if ((mode & op & 0007) == op)
 985                 return 0;
 986         return -EACCES;
 987 }
 988
 989 static inline int ctl_perm(ctl_table *table, int op)
 990 {
 991         int error;
 992         error = security_sysctl(table, op);
 993         if (error)
 994                 return error;
 995         return test_perm(table->mode, op);
 996 }
 997
 998 static int parse_table(int __user *name, int nlen,
 999                        void __user *oldval, size_t __user *oldlenp,
1000                        void __user *newval, size_t newlen,
1001                        ctl_table *table, void **context)
1002 {
1003         int n;
1004 repeat:
1005         if (!nlen)
1006                 return -ENOTDIR;
1007         if (get_user(n, name))
1008                 return -EFAULT;
1009         for ( ; table->ctl_name; table++) {
1010                 if (n == table->ctl_name || table->ctl_name == CTL_ANY) {
1011                         int error;
1012                         if (table->child) {
1013                                 if (ctl_perm(table, 001))
1014                                         return -EPERM;
1015                                 if (table->strategy) {
1016                                         error = table->strategy(
1017                                                 table, name, nlen,
1018                                                 oldval, oldlenp,
1019                                                 newval, newlen, context);
1020                                         if (error)
1021                                                 return error;
1022                                 }
1023                                 name++;
1024                                 nlen--;
1025                                 table = table->child;
1026                                 goto repeat;
1027                         }
1028                         error = do_sysctl_strategy(table, name, nlen,
1029                                                    oldval, oldlenp,
1030                                                    newval, newlen, context);
1031                         return error;
1032                 }
1033         }
1034         return -ENOTDIR;
1035 }
1036
1037 /* Perform the actual read/write of a sysctl table entry. */
1038 int do_sysctl_strategy (ctl_table *table,
1039                         int __user *name, int nlen,
1040                         void __user *oldval, size_t __user *oldlenp,
1041                         void __user *newval, size_t newlen, void **context)
1042 {
1043         int op = 0, rc;
1044         size_t len;
1045
1046         if (oldval)
1047                 op |= 004;
1048         if (newval)
1049                 op |= 002;
1050         if (ctl_perm(table, op))
1051                 return -EPERM;
1052
1053         if (table->strategy) {
1054                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1055                                      newval, newlen, context);
1056                 if (rc < 0)
1057                         return rc;
1058                 if (rc > 0)
1059                         return 0;
1060         }
1061
1062         /* If there is no strategy routine, or if the strategy returns
1063          * zero, proceed with automatic r/w */
1064         if (table->data && table->maxlen) {
1065                 if (oldval && oldlenp) {
1066                         if (get_user(len, oldlenp))
1067                                 return -EFAULT;
1068                         if (len) {
1069                                 if (len > table->maxlen)
1070                                         len = table->maxlen;
1071                                 if(copy_to_user(oldval, table->data, len))
1072                                         return -EFAULT;
1073                                 if(put_user(len, oldlenp))
1074                                         return -EFAULT;
1075                         }
1076                 }
1077                 if (newval && newlen) {
1078                         len = newlen;
1079                         if (len > table->maxlen)
1080                                 len = table->maxlen;
1081                         if(copy_from_user(table->data, newval, len))
1082                                 return -EFAULT;
1083                 }
1084         }
1085         return 0;
1086 }
1087
1088 /**
1089  * register_sysctl_table - register a sysctl hierarchy
1090  * @table: the top-level table structure
1091  * @insert_at_head: whether the entry should be inserted in front or at the end
1092  *
1093  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1094  * array. An entry with a ctl_name of 0 terminates the table.
1095  *
1096  * The members of the &ctl_table structure are used as follows:
1097  *
1098  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1099  *            must be unique within that level of sysctl
1100  *
1101  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1102  *            enter a sysctl file
1103  *
1104  * data - a pointer to data for use by proc_handler
1105  *
1106  * maxlen - the maximum size in bytes of the data
1107  *
1108  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1109  *
1110  * child - a pointer to the child sysctl table if this entry is a directory, or
1111  *         %NULL.
1112  *
1113  * proc_handler - the text handler routine (described below)
1114  *
1115  * strategy - the strategy routine (described below)
1116  *
1117  * de - for internal use by the sysctl routines
1118  *
1119  * extra1, extra2 - extra pointers usable by the proc handler routines
1120  *
1121  * Leaf nodes in the sysctl tree will be represented by a single file
1122  * under /proc; non-leaf nodes will be represented by directories.
1123  *
1124  * sysctl(2) can automatically manage read and write requests through
1125  * the sysctl table.  The data and maxlen fields of the ctl_table
1126  * struct enable minimal validation of the values being written to be
1127  * performed, and the mode field allows minimal authentication.
1128  *
1129  * More sophisticated management can be enabled by the provision of a
1130  * strategy routine with the table entry.  This will be called before
1131  * any automatic read or write of the data is performed.
1132  *
1133  * The strategy routine may return
1134  *
1135  * < 0 - Error occurred (error is passed to user process)
1136  *
1137  * 0   - OK - proceed with automatic read or write.
1138  *
1139  * > 0 - OK - read or write has been done by the strategy routine, so
1140  *       return immediately.
1141  *
1142  * There must be a proc_handler routine for any terminal nodes
1143  * mirrored under /proc/sys (non-terminals are handled by a built-in
1144  * directory handler).  Several default handlers are available to
1145  * cover common cases -
1146  *
1147  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1148  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1149  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1150  *
1151  * It is the handler's job to read the input buffer from user memory
1152  * and process it. The handler should return 0 on success.
1153  *
1154  * This routine returns %NULL on a failure to register, and a pointer
1155  * to the table header on success.
1156  */
1157 struct ctl_table_header *register_sysctl_table(ctl_table * table,
1158                                                int insert_at_head)
1159 {
1160         struct ctl_table_header *tmp;
1161         tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1162         if (!tmp)
1163                 return NULL;
1164         tmp->ctl_table = table;
1165         INIT_LIST_HEAD(&tmp->ctl_entry);
1166         if (insert_at_head)
1167                 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
1168         else
1169                 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1170 #ifdef CONFIG_PROC_FS
1171         register_proc_table(table, proc_sys_root);
1172 #endif
1173         return tmp;
1174 }
1175
1176 /**
1177  * unregister_sysctl_table - unregister a sysctl table hierarchy
1178  * @header: the header returned from register_sysctl_table
1179  *
1180  * Unregisters the sysctl table and all children. proc entries may not
1181  * actually be removed until they are no longer used by anyone.
1182  */
1183 void unregister_sysctl_table(struct ctl_table_header * header)
1184 {
1185         list_del(&header->ctl_entry);
1186 #ifdef CONFIG_PROC_FS
1187         unregister_proc_table(header->ctl_table, proc_sys_root);
1188 #endif
1189         kfree(header);
1190 }
1191
1192 /*
1193  * /proc/sys support
1194  */
1195
1196 #ifdef CONFIG_PROC_FS
1197
1198 /* Scan the sysctl entries in table and add them all into /proc */
1199 static void register_proc_table(ctl_table * table, struct proc_dir_entry *root)
1200 {
1201         struct proc_dir_entry *de;
1202         int len;
1203         mode_t mode;
1204
1205         for (; table->ctl_name; table++) {
1206                 /* Can't do anything without a proc name. */
1207                 if (!table->procname)
1208                         continue;
1209                 /* Maybe we can't do anything with it... */
1210                 if (!table->proc_handler && !table->child) {
1211                         printk(KERN_WARNING "SYSCTL: Can't register %s\n",
1212                                 table->procname);
1213                         continue;
1214                 }
1215
1216                 len = strlen(table->procname);
1217                 mode = table->mode;
1218
1219                 de = NULL;
1220                 if (table->proc_handler)
1221                         mode |= S_IFREG;
1222                 else {
1223                         mode |= S_IFDIR;
1224                         for (de = root->subdir; de; de = de->next) {
1225                                 if (proc_match(len, table->procname, de))
1226                                         break;
1227                         }
1228                         /* If the subdir exists already, de is non-NULL */
1229                 }
1230
1231                 if (!de) {
1232                         de = create_proc_entry(table->procname, mode, root);
1233                         if (!de)
1234                                 continue;
1235                         de->data = (void *) table;
1236                         if (table->proc_handler)
1237                                 de->proc_fops = &proc_sys_file_operations;
1238                 }
1239                 table->de = de;
1240                 if (de->mode & S_IFDIR)
1241                         register_proc_table(table->child, de);
1242         }
1243 }
1244
1245 /*
1246  * Unregister a /proc sysctl table and any subdirectories.
1247  */
1248 static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
1249 {
1250         struct proc_dir_entry *de;
1251         for (; table->ctl_name; table++) {
1252                 if (!(de = table->de))
1253                         continue;
1254                 if (de->mode & S_IFDIR) {
1255                         if (!table->child) {
1256                                 printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
1257                                 continue;
1258                         }
1259                         unregister_proc_table(table->child, de);
1260
1261                         /* Don't unregister directories which still have entries.. */
1262                         if (de->subdir)
1263                                 continue;
1264                 }
1265
1266                 /* Don't unregister proc entries that are still being used.. */
1267                 if (atomic_read(&de->count))
1268                         continue;
1269
1270                 table->de = NULL;
1271                 remove_proc_entry(table->procname, root);
1272         }
1273 }
1274
1275 static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
1276                           size_t count, loff_t *ppos)
1277 {
1278         int op;
1279         struct proc_dir_entry *de;
1280         struct ctl_table *table;
1281         size_t res;
1282         ssize_t error;
1283
1284         de = PDE(file->f_dentry->d_inode);
1285         if (!de || !de->data)
1286                 return -ENOTDIR;
1287         table = (struct ctl_table *) de->data;
1288         if (!table || !table->proc_handler)
1289                 return -ENOTDIR;
1290         op = (write ? 002 : 004);
1291         if (ctl_perm(table, op))
1292                 return -EPERM;
1293
1294         res = count;
1295
1296         /*
1297          * FIXME: we need to pass on ppos to the handler.
1298          */
1299
1300         error = (*table->proc_handler) (table, write, file, buf, &res);
1301         if (error)
1302                 return error;
1303         return res;
1304 }
1305
1306 static int proc_opensys(struct inode *inode, struct file *file)
1307 {
1308         if (file->f_mode & FMODE_WRITE) {
1309                 /*
1310                  * sysctl entries that are not writable,
1311                  * are _NOT_ writable, capabilities or not.
1312                  */
1313                 if (!(inode->i_mode & S_IWUSR))
1314                         return -EPERM;
1315         }
1316
1317         return 0;
1318 }
1319
1320 static ssize_t proc_readsys(struct file * file, char __user * buf,
1321                             size_t count, loff_t *ppos)
1322 {
1323         return do_rw_proc(0, file, buf, count, ppos);
1324 }
1325
1326 static ssize_t proc_writesys(struct file * file, const char __user * buf,
1327                              size_t count, loff_t *ppos)
1328 {
1329         return do_rw_proc(1, file, (char __user *) buf, count, ppos);
1330 }
1331
1332 /**
1333  * proc_dostring - read a string sysctl
1334  * @table: the sysctl table
1335  * @write: %TRUE if this is a write to the sysctl file
1336  * @filp: the file structure
1337  * @buffer: the user buffer
1338  * @lenp: the size of the user buffer
1339  *
1340  * Reads/writes a string from/to the user buffer. If the kernel
1341  * buffer provided is not large enough to hold the string, the
1342  * string is truncated. The copied string is %NULL-terminated.
1343  * If the string is being read by the user process, it is copied
1344  * and a newline '\n' is added. It is truncated if the buffer is
1345  * not large enough.
1346  *
1347  * Returns 0 on success.
1348  */
1349 int proc_dostring(ctl_table *table, int write, struct file *filp,
1350                   void __user *buffer, size_t *lenp)
1351 {
1352         size_t len;
1353         char __user *p;
1354         char c;
1355
1356         if (!table->data || !table->maxlen || !*lenp ||
1357             (filp->f_pos && !write)) {
1358                 *lenp = 0;
1359                 return 0;
1360         }
1361
1362         if (write) {
1363                 len = 0;
1364                 p = buffer;
1365                 while (len < *lenp) {
1366                         if (get_user(c, p++))
1367                                 return -EFAULT;
1368                         if (c == 0 || c == '\n')
1369                                 break;
1370                         len++;
1371                 }
1372                 if (len >= table->maxlen)
1373                         len = table->maxlen-1;
1374                 if(copy_from_user(table->data, buffer, len))
1375                         return -EFAULT;
1376                 ((char *) table->data)[len] = 0;
1377                 filp->f_pos += *lenp;
1378         } else {
1379                 len = strlen(table->data);
1380                 if (len > table->maxlen)
1381                         len = table->maxlen;
1382                 if (len > *lenp)
1383                         len = *lenp;
1384                 if (len)
1385                         if(copy_to_user(buffer, table->data, len))
1386                                 return -EFAULT;
1387                 if (len < *lenp) {
1388                         if(put_user('\n', ((char __user *) buffer) + len))
1389                                 return -EFAULT;
1390                         len++;
1391                 }
1392                 *lenp = len;
1393                 filp->f_pos += len;
1394         }
1395         return 0;
1396 }
1397
1398 /*
1399  *      Special case of dostring for the UTS structure. This has locks
1400  *      to observe. Should this be in kernel/sys.c ????
1401  */
1402
1403 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
1404                   void __user *buffer, size_t *lenp)
1405 {
1406         int r;
1407
1408         if (!write) {
1409                 down_read(&uts_sem);
1410                 r=proc_dostring(table,0,filp,buffer,lenp);
1411                 up_read(&uts_sem);
1412         } else {
1413                 down_write(&uts_sem);
1414                 r=proc_dostring(table,1,filp,buffer,lenp);
1415                 up_write(&uts_sem);
1416         }
1417         return r;
1418 }
1419
1420 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1421                                  int *valp,
1422                                  int write, void *data)
1423 {
1424         if (write) {
1425                 *valp = *negp ? -*lvalp : *lvalp;
1426         } else {
1427                 int val = *valp;
1428                 if (val < 0) {
1429                         *negp = -1;
1430                         *lvalp = (unsigned long)-val;
1431                 } else {
1432                         *negp = 0;
1433                         *lvalp = (unsigned long)val;
1434                 }
1435         }
1436         return 0;
1437 }
1438
1439 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1440                   void __user *buffer, size_t *lenp,
1441                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1442                               int write, void *data),
1443                   void *data)
1444 {
1445 #define TMPBUFLEN 20
1446         int *i, vleft, first=1, neg, val;
1447         unsigned long lval;
1448         size_t left, len;
1449
1450         char buf[TMPBUFLEN], *p;
1451         char __user *s = buffer;
1452
1453         if (!table->data || !table->maxlen || !*lenp ||
1454             (filp->f_pos && !write)) {
1455                 *lenp = 0;
1456                 return 0;
1457         }
1458
1459         i = (int *) table->data;
1460         vleft = table->maxlen / sizeof(*i);
1461         left = *lenp;
1462
1463         if (!conv)
1464                 conv = do_proc_dointvec_conv;
1465
1466         for (; left && vleft--; i++, first=0) {
1467                 if (write) {
1468                         while (left) {
1469                                 char c;
1470                                 if (get_user(c, s))
1471                                         return -EFAULT;
1472                                 if (!isspace(c))
1473                                         break;
1474                                 left--;
1475                                 s++;
1476                         }
1477                         if (!left)
1478                                 break;
1479                         neg = 0;
1480                         len = left;
1481                         if (len > sizeof(buf) - 1)
1482                                 len = sizeof(buf) - 1;
1483                         if (copy_from_user(buf, s, len))
1484                                 return -EFAULT;
1485                         buf[len] = 0;
1486                         p = buf;
1487                         if (*p == '-' && left > 1) {
1488                                 neg = 1;
1489                                 left--, p++;
1490                         }
1491                         if (*p < '0' || *p > '9')
1492                                 break;
1493
1494                         lval = simple_strtoul(p, &p, 0);
1495
1496                         len = p-buf;
1497                         if ((len < left) && *p && !isspace(*p))
1498                                 break;
1499                         if (neg)
1500                                 val = -val;
1501                         s += len;
1502                         left -= len;
1503
1504                         if (conv(&neg, &lval, i, 1, data))
1505                                 break;
1506                 } else {
1507                         p = buf;
1508                         if (!first)
1509                                 *p++ = '\t';
1510
1511                         if (conv(&neg, &lval, i, 0, data))
1512                                 break;
1513
1514                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
1515                         len = strlen(buf);
1516                         if (len > left)
1517                                 len = left;
1518                         if(copy_to_user(s, buf, len))
1519                                 return -EFAULT;
1520                         left -= len;
1521                         s += len;
1522                 }
1523         }
1524
1525         if (!write && !first && left) {
1526                 if(put_user('\n', s))
1527                         return -EFAULT;
1528                 left--, s++;
1529         }
1530         if (write) {
1531                 while (left) {
1532                         char c;
1533                         if (get_user(c, s++))
1534                                 return -EFAULT;
1535                         if (!isspace(c))
1536                                 break;
1537                         left--;
1538                 }
1539         }
1540         if (write && first)
1541                 return -EINVAL;
1542         *lenp -= left;
1543         filp->f_pos += *lenp;
1544         return 0;
1545 #undef TMPBUFLEN
1546 }
1547
1548 /**
1549  * proc_dointvec - read a vector of integers
1550  * @table: the sysctl table
1551  * @write: %TRUE if this is a write to the sysctl file
1552  * @filp: the file structure
1553  * @buffer: the user buffer
1554  * @lenp: the size of the user buffer
1555  *
1556  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1557  * values from/to the user buffer, treated as an ASCII string.
1558  *
1559  * Returns 0 on success.
1560  */
1561 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1562                      void __user *buffer, size_t *lenp)
1563 {
1564     return do_proc_dointvec(table,write,filp,buffer,lenp,
1565                             NULL,NULL);
1566 }
1567
1568 #define OP_SET  0
1569 #define OP_AND  1
1570 #define OP_OR   2
1571 #define OP_MAX  3
1572 #define OP_MIN  4
1573
1574 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1575                                       int *valp,
1576                                       int write, void *data)
1577 {
1578         int op = *(int *)data;
1579         if (write) {
1580                 int val = *negp ? -*lvalp : *lvalp;
1581                 switch(op) {
1582                 case OP_SET:    *valp = val; break;
1583                 case OP_AND:    *valp &= val; break;
1584                 case OP_OR:     *valp |= val; break;
1585                 case OP_MAX:    if(*valp < val)
1586                                         *valp = val;
1587                                 break;
1588                 case OP_MIN:    if(*valp > val)
1589                                 *valp = val;
1590                                 break;
1591                 }
1592         } else {
1593                 int val = *valp;
1594                 if (val < 0) {
1595                         *negp = -1;
1596                         *lvalp = (unsigned long)-val;
1597                 } else {
1598                         *negp = 0;
1599                         *lvalp = (unsigned long)val;
1600                 }
1601         }
1602         return 0;
1603 }
1604
1605 /*
1606  *      init may raise the set.
1607  */
1608
1609 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1610                         void __user *buffer, size_t *lenp)
1611 {
1612         int op;
1613
1614         if (!capable(CAP_SYS_MODULE)) {
1615                 return -EPERM;
1616         }
1617
1618         op = (current->pid == 1) ? OP_SET : OP_AND;
1619         return do_proc_dointvec(table,write,filp,buffer,lenp,
1620                                 do_proc_dointvec_bset_conv,&op);
1621 }
1622
1623 struct do_proc_dointvec_minmax_conv_param {
1624         int *min;
1625         int *max;
1626 };
1627
1628 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1629                                         int *valp,
1630                                         int write, void *data)
1631 {
1632         struct do_proc_dointvec_minmax_conv_param *param = data;
1633         if (write) {
1634                 int val = *negp ? -*lvalp : *lvalp;
1635                 if ((param->min && *param->min > val) ||
1636                     (param->max && *param->max < val))
1637                         return -EINVAL;
1638                 *valp = val;
1639         } else {
1640                 int val = *valp;
1641                 if (val < 0) {
1642                         *negp = -1;
1643                         *lvalp = (unsigned long)-val;
1644                 } else {
1645                         *negp = 0;
1646                         *lvalp = (unsigned long)val;
1647                 }
1648         }
1649         return 0;
1650 }
1651
1652 /**
1653  * proc_dointvec_minmax - read a vector of integers with min/max values
1654  * @table: the sysctl table
1655  * @write: %TRUE if this is a write to the sysctl file
1656  * @filp: the file structure
1657  * @buffer: the user buffer
1658  * @lenp: the size of the user buffer
1659  *
1660  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1661  * values from/to the user buffer, treated as an ASCII string.
1662  *
1663  * This routine will ensure the values are within the range specified by
1664  * table->extra1 (min) and table->extra2 (max).
1665  *
1666  * Returns 0 on success.
1667  */
1668 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1669                   void __user *buffer, size_t *lenp)
1670 {
1671         struct do_proc_dointvec_minmax_conv_param param = {
1672                 .min = (int *) table->extra1,
1673                 .max = (int *) table->extra2,
1674         };
1675         return do_proc_dointvec(table, write, filp, buffer, lenp,
1676                                 do_proc_dointvec_minmax_conv, &param);
1677 }
1678
1679 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1680                                      struct file *filp,
1681                                      void __user *buffer, size_t *lenp,
1682                                      unsigned long convmul,
1683                                      unsigned long convdiv)
1684 {
1685 #define TMPBUFLEN 20
1686         unsigned long *i, *min, *max, val;
1687         int vleft, first=1, neg;
1688         size_t len, left;
1689         char buf[TMPBUFLEN], *p;
1690         char __user *s = buffer;
1691
1692         if (!table->data || !table->maxlen || !*lenp ||
1693             (filp->f_pos && !write)) {
1694                 *lenp = 0;
1695                 return 0;
1696         }
1697
1698         i = (unsigned long *) table->data;
1699         min = (unsigned long *) table->extra1;
1700         max = (unsigned long *) table->extra2;
1701         vleft = table->maxlen / sizeof(unsigned long);
1702         left = *lenp;
1703
1704         for (; left && vleft--; i++, min++, max++, first=0) {
1705                 if (write) {
1706                         while (left) {
1707                                 char c;
1708                                 if (get_user(c, s))
1709                                         return -EFAULT;
1710                                 if (!isspace(c))
1711                                         break;
1712                                 left--;
1713                                 s++;
1714                         }
1715                         if (!left)
1716                                 break;
1717                         neg = 0;
1718                         len = left;
1719                         if (len > TMPBUFLEN-1)
1720                                 len = TMPBUFLEN-1;
1721                         if (copy_from_user(buf, s, len))
1722                                 return -EFAULT;
1723                         buf[len] = 0;
1724                         p = buf;
1725                         if (*p == '-' && left > 1) {
1726                                 neg = 1;
1727                                 left--, p++;
1728                         }
1729                         if (*p < '0' || *p > '9')
1730                                 break;
1731                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1732                         len = p-buf;
1733                         if ((len < left) && *p && !isspace(*p))
1734                                 break;
1735                         if (neg)
1736                                 val = -val;
1737                         s += len;
1738                         left -= len;
1739
1740                         if(neg)
1741                                 continue;
1742                         if ((min && val < *min) || (max && val > *max))
1743                                 continue;
1744                         *i = val;
1745                 } else {
1746                         p = buf;
1747                         if (!first)
1748                                 *p++ = '\t';
1749                         sprintf(p, "%lu", convdiv * (*i) / convmul);
1750                         len = strlen(buf);
1751                         if (len > left)
1752                                 len = left;
1753                         if(copy_to_user(s, buf, len))
1754                                 return -EFAULT;
1755                         left -= len;
1756                         s += len;
1757                 }
1758         }
1759
1760         if (!write && !first && left) {
1761                 if(put_user('\n', s))
1762                         return -EFAULT;
1763                 left--, s++;
1764         }
1765         if (write) {
1766                 while (left) {
1767                         char c;
1768                         if (get_user(c, s++))
1769                                 return -EFAULT;
1770                         if (!isspace(c))
1771                                 break;
1772                         left--;
1773                 }
1774         }
1775         if (write && first)
1776                 return -EINVAL;
1777         *lenp -= left;
1778         filp->f_pos += *lenp;
1779         return 0;
1780 #undef TMPBUFLEN
1781 }
1782
1783 /**
1784  * proc_doulongvec_minmax - read a vector of long integers with min/max values
1785  * @table: the sysctl table
1786  * @write: %TRUE if this is a write to the sysctl file
1787  * @filp: the file structure
1788  * @buffer: the user buffer
1789  * @lenp: the size of the user buffer
1790  *
1791  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1792  * values from/to the user buffer, treated as an ASCII string.
1793  *
1794  * This routine will ensure the values are within the range specified by
1795  * table->extra1 (min) and table->extra2 (max).
1796  *
1797  * Returns 0 on success.
1798  */
1799 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
1800                            void __user *buffer, size_t *lenp)
1801 {
1802     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, 1l, 1l);
1803 }
1804
1805 /**
1806  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
1807  * @table: the sysctl table
1808  * @write: %TRUE if this is a write to the sysctl file
1809  * @filp: the file structure
1810  * @buffer: the user buffer
1811  * @lenp: the size of the user buffer
1812  *
1813  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1814  * values from/to the user buffer, treated as an ASCII string. The values
1815  * are treated as milliseconds, and converted to jiffies when they are stored.
1816  *
1817  * This routine will ensure the values are within the range specified by
1818  * table->extra1 (min) and table->extra2 (max).
1819  *
1820  * Returns 0 on success.
1821  */
1822 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
1823                                       struct file *filp,
1824                                       void __user *buffer, size_t *lenp)
1825 {
1826     return do_proc_doulongvec_minmax(table, write, filp, buffer,
1827                                      lenp, HZ, 1000l);
1828 }
1829
1830
1831 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
1832                                          int *valp,
1833                                          int write, void *data)
1834 {
1835         if (write) {
1836                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
1837         } else {
1838                 int val = *valp;
1839                 unsigned long lval;
1840                 if (val < 0) {
1841                         *negp = -1;
1842                         lval = (unsigned long)-val;
1843                 } else {
1844                         *negp = 0;
1845                         lval = (unsigned long)val;
1846                 }
1847                 *lvalp = lval / HZ;
1848         }
1849         return 0;
1850 }
1851
1852 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
1853                                                 int *valp,
1854                                                 int write, void *data)
1855 {
1856         if (write) {
1857                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
1858         } else {
1859                 int val = *valp;
1860                 unsigned long lval;
1861                 if (val < 0) {
1862                         *negp = -1;
1863                         lval = (unsigned long)-val;
1864                 } else {
1865                         *negp = 0;
1866                         lval = (unsigned long)val;
1867                 }
1868                 *lvalp = jiffies_to_clock_t(lval);
1869         }
1870         return 0;
1871 }
1872
1873 /**
1874  * proc_dointvec_jiffies - read a vector of integers as seconds
1875  * @table: the sysctl table
1876  * @write: %TRUE if this is a write to the sysctl file
1877  * @filp: the file structure
1878  * @buffer: the user buffer
1879  * @lenp: the size of the user buffer
1880  *
1881  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1882  * values from/to the user buffer, treated as an ASCII string.
1883  * The values read are assumed to be in seconds, and are converted into
1884  * jiffies.
1885  *
1886  * Returns 0 on success.
1887  */
1888 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
1889                           void __user *buffer, size_t *lenp)
1890 {
1891     return do_proc_dointvec(table,write,filp,buffer,lenp,
1892                             do_proc_dointvec_jiffies_conv,NULL);
1893 }
1894
1895 /**
1896  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
1897  * @table: the sysctl table
1898  * @write: %TRUE if this is a write to the sysctl file
1899  * @filp: the file structure
1900  * @buffer: the user buffer
1901  * @lenp: the size of the user buffer
1902  *
1903  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1904  * values from/to the user buffer, treated as an ASCII string.
1905  * The values read are assumed to be in 1/USER_HZ seconds, and
1906  * are converted into jiffies.
1907  *
1908  * Returns 0 on success.
1909  */
1910 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
1911                                  void __user *buffer, size_t *lenp)
1912 {
1913     return do_proc_dointvec(table,write,filp,buffer,lenp,
1914                             do_proc_dointvec_userhz_jiffies_conv,NULL);
1915 }
1916
1917 #else /* CONFIG_PROC_FS */
1918
1919 int proc_dostring(ctl_table *table, int write, struct file *filp,
1920                   void __user *buffer, size_t *lenp)
1921 {
1922         return -ENOSYS;
1923 }
1924
1925 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
1926                             void __user *buffer, size_t *lenp)
1927 {
1928         return -ENOSYS;
1929 }
1930
1931 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1932                   void __user *buffer, size_t *lenp)
1933 {
1934         return -ENOSYS;
1935 }
1936
1937 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1938                         void __user *buffer, size_t *lenp)
1939 {
1940         return -ENOSYS;
1941 }
1942
1943 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1944                     void __user *buffer, size_t *lenp)
1945 {
1946         return -ENOSYS;
1947 }
1948
1949 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
1950                     void __user *buffer, size_t *lenp)
1951 {
1952         return -ENOSYS;
1953 }
1954
1955 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
1956                     void __user *buffer, size_t *lenp)
1957 {
1958         return -ENOSYS;
1959 }
1960
1961 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
1962                     void __user *buffer, size_t *lenp)
1963 {
1964         return -ENOSYS;
1965 }
1966
1967 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
1968                                       struct file *filp,
1969                                       void __user *buffer, size_t *lenp)
1970 {
1971     return -ENOSYS;
1972 }
1973
1974
1975 #endif /* CONFIG_PROC_FS */
1976
1977
1978 /*
1979  * General sysctl support routines
1980  */
1981
1982 /* The generic string strategy routine: */
1983 int sysctl_string(ctl_table *table, int __user *name, int nlen,
1984                   void __user *oldval, size_t __user *oldlenp,
1985                   void __user *newval, size_t newlen, void **context)
1986 {
1987         size_t l, len;
1988
1989         if (!table->data || !table->maxlen)
1990                 return -ENOTDIR;
1991
1992         if (oldval && oldlenp) {
1993                 if (get_user(len, oldlenp))
1994                         return -EFAULT;
1995                 if (len) {
1996                         l = strlen(table->data);
1997                         if (len > l) len = l;
1998                         if (len >= table->maxlen)
1999                                 len = table->maxlen;
2000                         if(copy_to_user(oldval, table->data, len))
2001                                 return -EFAULT;
2002                         if(put_user(0, ((char __user *) oldval) + len))
2003                                 return -EFAULT;
2004                         if(put_user(len, oldlenp))
2005                                 return -EFAULT;
2006                 }
2007         }
2008         if (newval && newlen) {
2009                 len = newlen;
2010                 if (len > table->maxlen)
2011                         len = table->maxlen;
2012                 if(copy_from_user(table->data, newval, len))
2013                         return -EFAULT;
2014                 if (len == table->maxlen)
2015                         len--;
2016                 ((char *) table->data)[len] = 0;
2017         }
2018         return 0;
2019 }
2020
2021 /*
2022  * This function makes sure that all of the integers in the vector
2023  * are between the minimum and maximum values given in the arrays
2024  * table->extra1 and table->extra2, respectively.
2025  */
2026 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2027                 void __user *oldval, size_t __user *oldlenp,
2028                 void __user *newval, size_t newlen, void **context)
2029 {
2030
2031         if (newval && newlen) {
2032                 int __user *vec = (int __user *) newval;
2033                 int *min = (int *) table->extra1;
2034                 int *max = (int *) table->extra2;
2035                 size_t length;
2036                 int i;
2037
2038                 if (newlen % sizeof(int) != 0)
2039                         return -EINVAL;
2040
2041                 if (!table->extra1 && !table->extra2)
2042                         return 0;
2043
2044                 if (newlen > table->maxlen)
2045                         newlen = table->maxlen;
2046                 length = newlen / sizeof(int);
2047
2048                 for (i = 0; i < length; i++) {
2049                         int value;
2050                         if (get_user(value, vec + i))
2051                                 return -EFAULT;
2052                         if (min && value < min[i])
2053                                 return -EINVAL;
2054                         if (max && value > max[i])
2055                                 return -EINVAL;
2056                 }
2057         }
2058         return 0;
2059 }
2060
2061 /* Strategy function to convert jiffies to seconds */
2062 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2063                 void __user *oldval, size_t __user *oldlenp,
2064                 void __user *newval, size_t newlen, void **context)
2065 {
2066         if (oldval) {
2067                 size_t olen;
2068                 if (oldlenp) {
2069                         if (get_user(olen, oldlenp))
2070                                 return -EFAULT;
2071                         if (olen!=sizeof(int))
2072                                 return -EINVAL;
2073                 }
2074                 if (put_user(*(int *)(table->data)/HZ, (int __user *)oldval) ||
2075                     (oldlenp && put_user(sizeof(int),oldlenp)))
2076                         return -EFAULT;
2077         }
2078         if (newval && newlen) {
2079                 int new;
2080                 if (newlen != sizeof(int))
2081                         return -EINVAL;
2082                 if (get_user(new, (int __user *)newval))
2083                         return -EFAULT;
2084                 *(int *)(table->data) = new*HZ;
2085         }
2086         return 1;
2087 }
2088
2089
2090 #else /* CONFIG_SYSCTL */
2091
2092
2093 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2094 {
2095         return -ENOSYS;
2096 }
2097
2098 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2099                   void __user *oldval, size_t __user *oldlenp,
2100                   void __user *newval, size_t newlen, void **context)
2101 {
2102         return -ENOSYS;
2103 }
2104
2105 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2106                 void __user *oldval, size_t __user *oldlenp,
2107                 void __user *newval, size_t newlen, void **context)
2108 {
2109         return -ENOSYS;
2110 }
2111
2112 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2113                 void __user *oldval, size_t __user *oldlenp,
2114                 void __user *newval, size_t newlen, void **context)
2115 {
2116         return -ENOSYS;
2117 }
2118
2119 int proc_dostring(ctl_table *table, int write, struct file *filp,
2120                   void __user *buffer, size_t *lenp)
2121 {
2122         return -ENOSYS;
2123 }
2124
2125 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2126                   void __user *buffer, size_t *lenp)
2127 {
2128         return -ENOSYS;
2129 }
2130
2131 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2132                         void __user *buffer, size_t *lenp)
2133 {
2134         return -ENOSYS;
2135 }
2136
2137 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2138                     void __user *buffer, size_t *lenp)
2139 {
2140         return -ENOSYS;
2141 }
2142
2143 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2144                           void __user *buffer, size_t *lenp)
2145 {
2146         return -ENOSYS;
2147 }
2148
2149 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2150                           void __user *buffer, size_t *lenp)
2151 {
2152         return -ENOSYS;
2153 }
2154
2155 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2156                     void __user *buffer, size_t *lenp)
2157 {
2158         return -ENOSYS;
2159 }
2160
2161 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2162                                       struct file *filp,
2163                                       void __user *buffer, size_t *lenp)
2164 {
2165     return -ENOSYS;
2166 }
2167
2168 struct ctl_table_header * register_sysctl_table(ctl_table * table,
2169                                                 int insert_at_head)
2170 {
2171         return 0;
2172 }
2173
2174 void unregister_sysctl_table(struct ctl_table_header * table)
2175 {
2176 }
2177
2178 #endif /* CONFIG_SYSCTL */
2179
2180 /*
2181  * No sense putting this after each symbol definition, twice,
2182  * exception granted :-)
2183  */
2184 EXPORT_SYMBOL(proc_dointvec);
2185 EXPORT_SYMBOL(proc_dointvec_jiffies);
2186 EXPORT_SYMBOL(proc_dointvec_minmax);
2187 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2188 EXPORT_SYMBOL(proc_dostring);
2189 EXPORT_SYMBOL(proc_doulongvec_minmax);
2190 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2191 EXPORT_SYMBOL(register_sysctl_table);
2192 EXPORT_SYMBOL(sysctl_intvec);
2193 EXPORT_SYMBOL(sysctl_jiffies);
2194 EXPORT_SYMBOL(sysctl_string);
2195 EXPORT_SYMBOL(unregister_sysctl_table);