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 <linux/dcache.h>
  43 #include <linux/syscalls.h>
  44
  45 #include <asm/uaccess.h>
  46 #include <asm/processor.h>
  47
  48 #ifdef CONFIG_ROOT_NFS
  49 #include <linux/nfs_fs.h>
  50 #endif
  51
  52 #if defined(CONFIG_SYSCTL)
  53
  54 /* External variables not in a header file. */
  55 extern int C_A_D;
  56 extern int sysctl_overcommit_memory;
  57 extern int sysctl_overcommit_ratio;
  58 extern int max_threads;
  59 extern int sysrq_enabled;
  60 extern int core_uses_pid;
  61 extern int suid_dumpable;
  62 extern char core_pattern[];
  63 extern int cad_pid;
  64 extern int pid_max;
  65 extern int min_free_kbytes;
  66 extern int printk_ratelimit_jiffies;
  67 extern int printk_ratelimit_burst;
  68 extern int pid_max_min, pid_max_max;
  69
  70 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
  71 int unknown_nmi_panic;
  72 extern int proc_unknown_nmi_panic(ctl_table *, int, struct file *,
  73                                   void __user *, size_t *, loff_t *);
  74 #endif
  75
  76 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
  77 static int maxolduid = 65535;
  78 static int minolduid;
  79
  80 static int ngroups_max = NGROUPS_MAX;
  81
  82 #ifdef CONFIG_KMOD
  83 extern char modprobe_path[];
  84 #endif
  85 #ifdef CONFIG_HOTPLUG
  86 extern char hotplug_path[];
  87 #endif
  88 #ifdef CONFIG_CHR_DEV_SG
  89 extern int sg_big_buff;
  90 #endif
  91 #ifdef CONFIG_SYSVIPC
  92 extern size_t shm_ctlmax;
  93 extern size_t shm_ctlall;
  94 extern int shm_ctlmni;
  95 extern int msg_ctlmax;
  96 extern int msg_ctlmnb;
  97 extern int msg_ctlmni;
  98 extern int sem_ctls[];
  99 #endif
 100
 101 #ifdef __sparc__
 102 extern char reboot_command [];
 103 extern int stop_a_enabled;
 104 extern int scons_pwroff;
 105 #endif
 106
 107 #ifdef __hppa__
 108 extern int pwrsw_enabled;
 109 extern int unaligned_enabled;
 110 #endif
 111
 112 #ifdef CONFIG_ARCH_S390
 113 #ifdef CONFIG_MATHEMU
 114 extern int sysctl_ieee_emulation_warnings;
 115 #endif
 116 extern int sysctl_userprocess_debug;
 117 #endif
 118
 119 extern int sysctl_hz_timer;
 120
 121 #ifdef CONFIG_BSD_PROCESS_ACCT
 122 extern int acct_parm[];
 123 #endif
 124
 125 int randomize_va_space = 1;
 126
 127 static int parse_table(int __user *, int, void __user *, size_t __user *, void __user *, size_t,
 128                        ctl_table *, void **);
 129 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
 130                   void __user *buffer, size_t *lenp, loff_t *ppos);
 131
 132 static ctl_table root_table[];
 133 static struct ctl_table_header root_table_header =
 134         { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
 135
 136 static ctl_table kern_table[];
 137 static ctl_table vm_table[];
 138 #ifdef CONFIG_NET
 139 extern ctl_table net_table[];
 140 #endif
 141 static ctl_table proc_table[];
 142 static ctl_table fs_table[];
 143 static ctl_table debug_table[];
 144 static ctl_table dev_table[];
 145 extern ctl_table random_table[];
 146 #ifdef CONFIG_UNIX98_PTYS
 147 extern ctl_table pty_table[];
 148 #endif
 149
 150 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 151 int sysctl_legacy_va_layout;
 152 #endif
 153
 154 /* /proc declarations: */
 155
 156 #ifdef CONFIG_PROC_FS
 157
 158 static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
 159 static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
 160 static int proc_opensys(struct inode *, struct file *);
 161
 162 struct file_operations proc_sys_file_operations = {
 163         .open           = proc_opensys,
 164         .read           = proc_readsys,
 165         .write          = proc_writesys,
 166 };
 167
 168 extern struct proc_dir_entry *proc_sys_root;
 169
 170 static void register_proc_table(ctl_table *, struct proc_dir_entry *);
 171 static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
 172 #endif
 173
 174 /* The default sysctl tables: */
 175
 176 static ctl_table root_table[] = {
 177         {
 178                 .ctl_name       = CTL_KERN,
 179                 .procname       = "kernel",
 180                 .mode           = 0555,
 181                 .child          = kern_table,
 182         },
 183         {
 184                 .ctl_name       = CTL_VM,
 185                 .procname       = "vm",
 186                 .mode           = 0555,
 187                 .child          = vm_table,
 188         },
 189 #ifdef CONFIG_NET
 190         {
 191                 .ctl_name       = CTL_NET,
 192                 .procname       = "net",
 193                 .mode           = 0555,
 194                 .child          = net_table,
 195         },
 196 #endif
 197         {
 198                 .ctl_name       = CTL_PROC,
 199                 .procname       = "proc",
 200                 .mode           = 0555,
 201                 .child          = proc_table,
 202         },
 203         {
 204                 .ctl_name       = CTL_FS,
 205                 .procname       = "fs",
 206                 .mode           = 0555,
 207                 .child          = fs_table,
 208         },
 209         {
 210                 .ctl_name       = CTL_DEBUG,
 211                 .procname       = "debug",
 212                 .mode           = 0555,
 213                 .child          = debug_table,
 214         },
 215         {
 216                 .ctl_name       = CTL_DEV,
 217                 .procname       = "dev",
 218                 .mode           = 0555,
 219                 .child          = dev_table,
 220         },
 221         { .ctl_name = 0 }
 222 };
 223
 224 static ctl_table kern_table[] = {
 225         {
 226                 .ctl_name       = KERN_OSTYPE,
 227                 .procname       = "ostype",
 228                 .data           = system_utsname.sysname,
 229                 .maxlen         = sizeof(system_utsname.sysname),
 230                 .mode           = 0444,
 231                 .proc_handler   = &proc_doutsstring,
 232                 .strategy       = &sysctl_string,
 233         },
 234         {
 235                 .ctl_name       = KERN_OSRELEASE,
 236                 .procname       = "osrelease",
 237                 .data           = system_utsname.release,
 238                 .maxlen         = sizeof(system_utsname.release),
 239                 .mode           = 0444,
 240                 .proc_handler   = &proc_doutsstring,
 241                 .strategy       = &sysctl_string,
 242         },
 243         {
 244                 .ctl_name       = KERN_VERSION,
 245                 .procname       = "version",
 246                 .data           = system_utsname.version,
 247                 .maxlen         = sizeof(system_utsname.version),
 248                 .mode           = 0444,
 249                 .proc_handler   = &proc_doutsstring,
 250                 .strategy       = &sysctl_string,
 251         },
 252         {
 253                 .ctl_name       = KERN_NODENAME,
 254                 .procname       = "hostname",
 255                 .data           = system_utsname.nodename,
 256                 .maxlen         = sizeof(system_utsname.nodename),
 257                 .mode           = 0644,
 258                 .proc_handler   = &proc_doutsstring,
 259                 .strategy       = &sysctl_string,
 260         },
 261         {
 262                 .ctl_name       = KERN_DOMAINNAME,
 263                 .procname       = "domainname",
 264                 .data           = system_utsname.domainname,
 265                 .maxlen         = sizeof(system_utsname.domainname),
 266                 .mode           = 0644,
 267                 .proc_handler   = &proc_doutsstring,
 268                 .strategy       = &sysctl_string,
 269         },
 270         {
 271                 .ctl_name       = KERN_PANIC,
 272                 .procname       = "panic",
 273                 .data           = &panic_timeout,
 274                 .maxlen         = sizeof(int),
 275                 .mode           = 0644,
 276                 .proc_handler   = &proc_dointvec,
 277         },
 278         {
 279                 .ctl_name       = KERN_CORE_USES_PID,
 280                 .procname       = "core_uses_pid",
 281                 .data           = &core_uses_pid,
 282                 .maxlen         = sizeof(int),
 283                 .mode           = 0644,
 284                 .proc_handler   = &proc_dointvec,
 285         },
 286         {
 287                 .ctl_name       = KERN_CORE_PATTERN,
 288                 .procname       = "core_pattern",
 289                 .data           = core_pattern,
 290                 .maxlen         = 64,
 291                 .mode           = 0644,
 292                 .proc_handler   = &proc_dostring,
 293                 .strategy       = &sysctl_string,
 294         },
 295         {
 296                 .ctl_name       = KERN_TAINTED,
 297                 .procname       = "tainted",
 298                 .data           = &tainted,
 299                 .maxlen         = sizeof(int),
 300                 .mode           = 0444,
 301                 .proc_handler   = &proc_dointvec,
 302         },
 303         {
 304                 .ctl_name       = KERN_CAP_BSET,
 305                 .procname       = "cap-bound",
 306                 .data           = &cap_bset,
 307                 .maxlen         = sizeof(kernel_cap_t),
 308                 .mode           = 0600,
 309                 .proc_handler   = &proc_dointvec_bset,
 310         },
 311 #ifdef CONFIG_BLK_DEV_INITRD
 312         {
 313                 .ctl_name       = KERN_REALROOTDEV,
 314                 .procname       = "real-root-dev",
 315                 .data           = &real_root_dev,
 316                 .maxlen         = sizeof(int),
 317                 .mode           = 0644,
 318                 .proc_handler   = &proc_dointvec,
 319         },
 320 #endif
 321 #ifdef __sparc__
 322         {
 323                 .ctl_name       = KERN_SPARC_REBOOT,
 324                 .procname       = "reboot-cmd",
 325                 .data           = reboot_command,
 326                 .maxlen         = 256,
 327                 .mode           = 0644,
 328                 .proc_handler   = &proc_dostring,
 329                 .strategy       = &sysctl_string,
 330         },
 331         {
 332                 .ctl_name       = KERN_SPARC_STOP_A,
 333                 .procname       = "stop-a",
 334                 .data           = &stop_a_enabled,
 335                 .maxlen         = sizeof (int),
 336                 .mode           = 0644,
 337                 .proc_handler   = &proc_dointvec,
 338         },
 339         {
 340                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 341                 .procname       = "scons-poweroff",
 342                 .data           = &scons_pwroff,
 343                 .maxlen         = sizeof (int),
 344                 .mode           = 0644,
 345                 .proc_handler   = &proc_dointvec,
 346         },
 347 #endif
 348 #ifdef __hppa__
 349         {
 350                 .ctl_name       = KERN_HPPA_PWRSW,
 351                 .procname       = "soft-power",
 352                 .data           = &pwrsw_enabled,
 353                 .maxlen         = sizeof (int),
 354                 .mode           = 0644,
 355                 .proc_handler   = &proc_dointvec,
 356         },
 357         {
 358                 .ctl_name       = KERN_HPPA_UNALIGNED,
 359                 .procname       = "unaligned-trap",
 360                 .data           = &unaligned_enabled,
 361                 .maxlen         = sizeof (int),
 362                 .mode           = 0644,
 363                 .proc_handler   = &proc_dointvec,
 364         },
 365 #endif
 366         {
 367                 .ctl_name       = KERN_CTLALTDEL,
 368                 .procname       = "ctrl-alt-del",
 369                 .data           = &C_A_D,
 370                 .maxlen         = sizeof(int),
 371                 .mode           = 0644,
 372                 .proc_handler   = &proc_dointvec,
 373         },
 374         {
 375                 .ctl_name       = KERN_PRINTK,
 376                 .procname       = "printk",
 377                 .data           = &console_loglevel,
 378                 .maxlen         = 4*sizeof(int),
 379                 .mode           = 0644,
 380                 .proc_handler   = &proc_dointvec,
 381         },
 382 #ifdef CONFIG_KMOD
 383         {
 384                 .ctl_name       = KERN_MODPROBE,
 385                 .procname       = "modprobe",
 386                 .data           = &modprobe_path,
 387                 .maxlen         = KMOD_PATH_LEN,
 388                 .mode           = 0644,
 389                 .proc_handler   = &proc_dostring,
 390                 .strategy       = &sysctl_string,
 391         },
 392 #endif
 393 #ifdef CONFIG_HOTPLUG
 394         {
 395                 .ctl_name       = KERN_HOTPLUG,
 396                 .procname       = "hotplug",
 397                 .data           = &hotplug_path,
 398                 .maxlen         = HOTPLUG_PATH_LEN,
 399                 .mode           = 0644,
 400                 .proc_handler   = &proc_dostring,
 401                 .strategy       = &sysctl_string,
 402         },
 403 #endif
 404 #ifdef CONFIG_CHR_DEV_SG
 405         {
 406                 .ctl_name       = KERN_SG_BIG_BUFF,
 407                 .procname       = "sg-big-buff",
 408                 .data           = &sg_big_buff,
 409                 .maxlen         = sizeof (int),
 410                 .mode           = 0444,
 411                 .proc_handler   = &proc_dointvec,
 412         },
 413 #endif
 414 #ifdef CONFIG_BSD_PROCESS_ACCT
 415         {
 416                 .ctl_name       = KERN_ACCT,
 417                 .procname       = "acct",
 418                 .data           = &acct_parm,
 419                 .maxlen         = 3*sizeof(int),
 420                 .mode           = 0644,
 421                 .proc_handler   = &proc_dointvec,
 422         },
 423 #endif
 424 #ifdef CONFIG_SYSVIPC
 425         {
 426                 .ctl_name       = KERN_SHMMAX,
 427                 .procname       = "shmmax",
 428                 .data           = &shm_ctlmax,
 429                 .maxlen         = sizeof (size_t),
 430                 .mode           = 0644,
 431                 .proc_handler   = &proc_doulongvec_minmax,
 432         },
 433         {
 434                 .ctl_name       = KERN_SHMALL,
 435                 .procname       = "shmall",
 436                 .data           = &shm_ctlall,
 437                 .maxlen         = sizeof (size_t),
 438                 .mode           = 0644,
 439                 .proc_handler   = &proc_doulongvec_minmax,
 440         },
 441         {
 442                 .ctl_name       = KERN_SHMMNI,
 443                 .procname       = "shmmni",
 444                 .data           = &shm_ctlmni,
 445                 .maxlen         = sizeof (int),
 446                 .mode           = 0644,
 447                 .proc_handler   = &proc_dointvec,
 448         },
 449         {
 450                 .ctl_name       = KERN_MSGMAX,
 451                 .procname       = "msgmax",
 452                 .data           = &msg_ctlmax,
 453                 .maxlen         = sizeof (int),
 454                 .mode           = 0644,
 455                 .proc_handler   = &proc_dointvec,
 456         },
 457         {
 458                 .ctl_name       = KERN_MSGMNI,
 459                 .procname       = "msgmni",
 460                 .data           = &msg_ctlmni,
 461                 .maxlen         = sizeof (int),
 462                 .mode           = 0644,
 463                 .proc_handler   = &proc_dointvec,
 464         },
 465         {
 466                 .ctl_name       = KERN_MSGMNB,
 467                 .procname       =  "msgmnb",
 468                 .data           = &msg_ctlmnb,
 469                 .maxlen         = sizeof (int),
 470                 .mode           = 0644,
 471                 .proc_handler   = &proc_dointvec,
 472         },
 473         {
 474                 .ctl_name       = KERN_SEM,
 475                 .procname       = "sem",
 476                 .data           = &sem_ctls,
 477                 .maxlen         = 4*sizeof (int),
 478                 .mode           = 0644,
 479                 .proc_handler   = &proc_dointvec,
 480         },
 481 #endif
 482 #ifdef CONFIG_MAGIC_SYSRQ
 483         {
 484                 .ctl_name       = KERN_SYSRQ,
 485                 .procname       = "sysrq",
 486                 .data           = &sysrq_enabled,
 487                 .maxlen         = sizeof (int),
 488                 .mode           = 0644,
 489                 .proc_handler   = &proc_dointvec,
 490         },
 491 #endif
 492         {
 493                 .ctl_name       = KERN_CADPID,
 494                 .procname       = "cad_pid",
 495                 .data           = &cad_pid,
 496                 .maxlen         = sizeof (int),
 497                 .mode           = 0600,
 498                 .proc_handler   = &proc_dointvec,
 499         },
 500         {
 501                 .ctl_name       = KERN_MAX_THREADS,
 502                 .procname       = "threads-max",
 503                 .data           = &max_threads,
 504                 .maxlen         = sizeof(int),
 505                 .mode           = 0644,
 506                 .proc_handler   = &proc_dointvec,
 507         },
 508         {
 509                 .ctl_name       = KERN_RANDOM,
 510                 .procname       = "random",
 511                 .mode           = 0555,
 512                 .child          = random_table,
 513         },
 514 #ifdef CONFIG_UNIX98_PTYS
 515         {
 516                 .ctl_name       = KERN_PTY,
 517                 .procname       = "pty",
 518                 .mode           = 0555,
 519                 .child          = pty_table,
 520         },
 521 #endif
 522         {
 523                 .ctl_name       = KERN_OVERFLOWUID,
 524                 .procname       = "overflowuid",
 525                 .data           = &overflowuid,
 526                 .maxlen         = sizeof(int),
 527                 .mode           = 0644,
 528                 .proc_handler   = &proc_dointvec_minmax,
 529                 .strategy       = &sysctl_intvec,
 530                 .extra1         = &minolduid,
 531                 .extra2         = &maxolduid,
 532         },
 533         {
 534                 .ctl_name       = KERN_OVERFLOWGID,
 535                 .procname       = "overflowgid",
 536                 .data           = &overflowgid,
 537                 .maxlen         = sizeof(int),
 538                 .mode           = 0644,
 539                 .proc_handler   = &proc_dointvec_minmax,
 540                 .strategy       = &sysctl_intvec,
 541                 .extra1         = &minolduid,
 542                 .extra2         = &maxolduid,
 543         },
 544 #ifdef CONFIG_ARCH_S390
 545 #ifdef CONFIG_MATHEMU
 546         {
 547                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 548                 .procname       = "ieee_emulation_warnings",
 549                 .data           = &sysctl_ieee_emulation_warnings,
 550                 .maxlen         = sizeof(int),
 551                 .mode           = 0644,
 552                 .proc_handler   = &proc_dointvec,
 553         },
 554 #endif
 555 #ifdef CONFIG_NO_IDLE_HZ
 556         {
 557                 .ctl_name       = KERN_HZ_TIMER,
 558                 .procname       = "hz_timer",
 559                 .data           = &sysctl_hz_timer,
 560                 .maxlen         = sizeof(int),
 561                 .mode           = 0644,
 562                 .proc_handler   = &proc_dointvec,
 563         },
 564 #endif
 565         {
 566                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 567                 .procname       = "userprocess_debug",
 568                 .data           = &sysctl_userprocess_debug,
 569                 .maxlen         = sizeof(int),
 570                 .mode           = 0644,
 571                 .proc_handler   = &proc_dointvec,
 572         },
 573 #endif
 574         {
 575                 .ctl_name       = KERN_PIDMAX,
 576                 .procname       = "pid_max",
 577                 .data           = &pid_max,
 578                 .maxlen         = sizeof (int),
 579                 .mode           = 0644,
 580                 .proc_handler   = &proc_dointvec_minmax,
 581                 .strategy       = sysctl_intvec,
 582                 .extra1         = &pid_max_min,
 583                 .extra2         = &pid_max_max,
 584         },
 585         {
 586                 .ctl_name       = KERN_PANIC_ON_OOPS,
 587                 .procname       = "panic_on_oops",
 588                 .data           = &panic_on_oops,
 589                 .maxlen         = sizeof(int),
 590                 .mode           = 0644,
 591                 .proc_handler   = &proc_dointvec,
 592         },
 593         {
 594                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 595                 .procname       = "printk_ratelimit",
 596                 .data           = &printk_ratelimit_jiffies,
 597                 .maxlen         = sizeof(int),
 598                 .mode           = 0644,
 599                 .proc_handler   = &proc_dointvec_jiffies,
 600                 .strategy       = &sysctl_jiffies,
 601         },
 602         {
 603                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 604                 .procname       = "printk_ratelimit_burst",
 605                 .data           = &printk_ratelimit_burst,
 606                 .maxlen         = sizeof(int),
 607                 .mode           = 0644,
 608                 .proc_handler   = &proc_dointvec,
 609         },
 610         {
 611                 .ctl_name       = KERN_NGROUPS_MAX,
 612                 .procname       = "ngroups_max",
 613                 .data           = &ngroups_max,
 614                 .maxlen         = sizeof (int),
 615                 .mode           = 0444,
 616                 .proc_handler   = &proc_dointvec,
 617         },
 618 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 619         {
 620                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
 621                 .procname       = "unknown_nmi_panic",
 622                 .data           = &unknown_nmi_panic,
 623                 .maxlen         = sizeof (int),
 624                 .mode           = 0644,
 625                 .proc_handler   = &proc_unknown_nmi_panic,
 626         },
 627 #endif
 628 #if defined(CONFIG_X86)
 629         {
 630                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 631                 .procname       = "bootloader_type",
 632                 .data           = &bootloader_type,
 633                 .maxlen         = sizeof (int),
 634                 .mode           = 0444,
 635                 .proc_handler   = &proc_dointvec,
 636         },
 637 #endif
 638         {
 639                 .ctl_name       = KERN_RANDOMIZE,
 640                 .procname       = "randomize_va_space",
 641                 .data           = &randomize_va_space,
 642                 .maxlen         = sizeof(int),
 643                 .mode           = 0644,
 644                 .proc_handler   = &proc_dointvec,
 645         },
 646
 647         { .ctl_name = 0 }
 648 };
 649
 650 /* Constants for minimum and maximum testing in vm_table.
 651    We use these as one-element integer vectors. */
 652 static int zero;
 653 static int one_hundred = 100;
 654
 655
 656 static ctl_table vm_table[] = {
 657         {
 658                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
 659                 .procname       = "overcommit_memory",
 660                 .data           = &sysctl_overcommit_memory,
 661                 .maxlen         = sizeof(sysctl_overcommit_memory),
 662                 .mode           = 0644,
 663                 .proc_handler   = &proc_dointvec,
 664         },
 665         {
 666                 .ctl_name       = VM_OVERCOMMIT_RATIO,
 667                 .procname       = "overcommit_ratio",
 668                 .data           = &sysctl_overcommit_ratio,
 669                 .maxlen         = sizeof(sysctl_overcommit_ratio),
 670                 .mode           = 0644,
 671                 .proc_handler   = &proc_dointvec,
 672         },
 673         {
 674                 .ctl_name       = VM_PAGE_CLUSTER,
 675                 .procname       = "page-cluster",
 676                 .data           = &page_cluster,
 677                 .maxlen         = sizeof(int),
 678                 .mode           = 0644,
 679                 .proc_handler   = &proc_dointvec,
 680         },
 681         {
 682                 .ctl_name       = VM_DIRTY_BACKGROUND,
 683                 .procname       = "dirty_background_ratio",
 684                 .data           = &dirty_background_ratio,
 685                 .maxlen         = sizeof(dirty_background_ratio),
 686                 .mode           = 0644,
 687                 .proc_handler   = &proc_dointvec_minmax,
 688                 .strategy       = &sysctl_intvec,
 689                 .extra1         = &zero,
 690                 .extra2         = &one_hundred,
 691         },
 692         {
 693                 .ctl_name       = VM_DIRTY_RATIO,
 694                 .procname       = "dirty_ratio",
 695                 .data           = &vm_dirty_ratio,
 696                 .maxlen         = sizeof(vm_dirty_ratio),
 697                 .mode           = 0644,
 698                 .proc_handler   = &proc_dointvec_minmax,
 699                 .strategy       = &sysctl_intvec,
 700                 .extra1         = &zero,
 701                 .extra2         = &one_hundred,
 702         },
 703         {
 704                 .ctl_name       = VM_DIRTY_WB_CS,
 705                 .procname       = "dirty_writeback_centisecs",
 706                 .data           = &dirty_writeback_centisecs,
 707                 .maxlen         = sizeof(dirty_writeback_centisecs),
 708                 .mode           = 0644,
 709                 .proc_handler   = &dirty_writeback_centisecs_handler,
 710         },
 711         {
 712                 .ctl_name       = VM_DIRTY_EXPIRE_CS,
 713                 .procname       = "dirty_expire_centisecs",
 714                 .data           = &dirty_expire_centisecs,
 715                 .maxlen         = sizeof(dirty_expire_centisecs),
 716                 .mode           = 0644,
 717                 .proc_handler   = &proc_dointvec,
 718         },
 719         {
 720                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
 721                 .procname       = "nr_pdflush_threads",
 722                 .data           = &nr_pdflush_threads,
 723                 .maxlen         = sizeof nr_pdflush_threads,
 724                 .mode           = 0444 /* read-only*/,
 725                 .proc_handler   = &proc_dointvec,
 726         },
 727         {
 728                 .ctl_name       = VM_SWAPPINESS,
 729                 .procname       = "swappiness",
 730                 .data           = &vm_swappiness,
 731                 .maxlen         = sizeof(vm_swappiness),
 732                 .mode           = 0644,
 733                 .proc_handler   = &proc_dointvec_minmax,
 734                 .strategy       = &sysctl_intvec,
 735                 .extra1         = &zero,
 736                 .extra2         = &one_hundred,
 737         },
 738 #ifdef CONFIG_HUGETLB_PAGE
 739          {
 740                 .ctl_name       = VM_HUGETLB_PAGES,
 741                 .procname       = "nr_hugepages",
 742                 .data           = &max_huge_pages,
 743                 .maxlen         = sizeof(unsigned long),
 744                 .mode           = 0644,
 745                 .proc_handler   = &hugetlb_sysctl_handler,
 746                 .extra1         = (void *)&hugetlb_zero,
 747                 .extra2         = (void *)&hugetlb_infinity,
 748          },
 749          {
 750                 .ctl_name       = VM_HUGETLB_GROUP,
 751                 .procname       = "hugetlb_shm_group",
 752                 .data           = &sysctl_hugetlb_shm_group,
 753                 .maxlen         = sizeof(gid_t),
 754                 .mode           = 0644,
 755                 .proc_handler   = &proc_dointvec,
 756          },
 757 #endif
 758         {
 759                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
 760                 .procname       = "lowmem_reserve_ratio",
 761                 .data           = &sysctl_lowmem_reserve_ratio,
 762                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
 763                 .mode           = 0644,
 764                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
 765                 .strategy       = &sysctl_intvec,
 766         },
 767         {
 768                 .ctl_name       = VM_MIN_FREE_KBYTES,
 769                 .procname       = "min_free_kbytes",
 770                 .data           = &min_free_kbytes,
 771                 .maxlen         = sizeof(min_free_kbytes),
 772                 .mode           = 0644,
 773                 .proc_handler   = &min_free_kbytes_sysctl_handler,
 774                 .strategy       = &sysctl_intvec,
 775                 .extra1         = &zero,
 776         },
 777 #ifdef CONFIG_MMU
 778         {
 779                 .ctl_name       = VM_MAX_MAP_COUNT,
 780                 .procname       = "max_map_count",
 781                 .data           = &sysctl_max_map_count,
 782                 .maxlen         = sizeof(sysctl_max_map_count),
 783                 .mode           = 0644,
 784                 .proc_handler   = &proc_dointvec
 785         },
 786 #endif
 787         {
 788                 .ctl_name       = VM_LAPTOP_MODE,
 789                 .procname       = "laptop_mode",
 790                 .data           = &laptop_mode,
 791                 .maxlen         = sizeof(laptop_mode),
 792                 .mode           = 0644,
 793                 .proc_handler   = &proc_dointvec,
 794                 .strategy       = &sysctl_intvec,
 795                 .extra1         = &zero,
 796         },
 797         {
 798                 .ctl_name       = VM_BLOCK_DUMP,
 799                 .procname       = "block_dump",
 800                 .data           = &block_dump,
 801                 .maxlen         = sizeof(block_dump),
 802                 .mode           = 0644,
 803                 .proc_handler   = &proc_dointvec,
 804                 .strategy       = &sysctl_intvec,
 805                 .extra1         = &zero,
 806         },
 807         {
 808                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
 809                 .procname       = "vfs_cache_pressure",
 810                 .data           = &sysctl_vfs_cache_pressure,
 811                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
 812                 .mode           = 0644,
 813                 .proc_handler   = &proc_dointvec,
 814                 .strategy       = &sysctl_intvec,
 815                 .extra1         = &zero,
 816         },
 817 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 818         {
 819                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
 820                 .procname       = "legacy_va_layout",
 821                 .data           = &sysctl_legacy_va_layout,
 822                 .maxlen         = sizeof(sysctl_legacy_va_layout),
 823                 .mode           = 0644,
 824                 .proc_handler   = &proc_dointvec,
 825                 .strategy       = &sysctl_intvec,
 826                 .extra1         = &zero,
 827         },
 828 #endif
 829 #ifdef CONFIG_SWAP
 830         {
 831                 .ctl_name       = VM_SWAP_TOKEN_TIMEOUT,
 832                 .procname       = "swap_token_timeout",
 833                 .data           = &swap_token_default_timeout,
 834                 .maxlen         = sizeof(swap_token_default_timeout),
 835                 .mode           = 0644,
 836                 .proc_handler   = &proc_dointvec_jiffies,
 837                 .strategy       = &sysctl_jiffies,
 838         },
 839 #endif
 840         { .ctl_name = 0 }
 841 };
 842
 843 static ctl_table proc_table[] = {
 844         { .ctl_name = 0 }
 845 };
 846
 847 static ctl_table fs_table[] = {
 848         {
 849                 .ctl_name       = FS_NRINODE,
 850                 .procname       = "inode-nr",
 851                 .data           = &inodes_stat,
 852                 .maxlen         = 2*sizeof(int),
 853                 .mode           = 0444,
 854                 .proc_handler   = &proc_dointvec,
 855         },
 856         {
 857                 .ctl_name       = FS_STATINODE,
 858                 .procname       = "inode-state",
 859                 .data           = &inodes_stat,
 860                 .maxlen         = 7*sizeof(int),
 861                 .mode           = 0444,
 862                 .proc_handler   = &proc_dointvec,
 863         },
 864         {
 865                 .ctl_name       = FS_NRFILE,
 866                 .procname       = "file-nr",
 867                 .data           = &files_stat,
 868                 .maxlen         = 3*sizeof(int),
 869                 .mode           = 0444,
 870                 .proc_handler   = &proc_dointvec,
 871         },
 872         {
 873                 .ctl_name       = FS_MAXFILE,
 874                 .procname       = "file-max",
 875                 .data           = &files_stat.max_files,
 876                 .maxlen         = sizeof(int),
 877                 .mode           = 0644,
 878                 .proc_handler   = &proc_dointvec,
 879         },
 880         {
 881                 .ctl_name       = FS_DENTRY,
 882                 .procname       = "dentry-state",
 883                 .data           = &dentry_stat,
 884                 .maxlen         = 6*sizeof(int),
 885                 .mode           = 0444,
 886                 .proc_handler   = &proc_dointvec,
 887         },
 888         {
 889                 .ctl_name       = FS_OVERFLOWUID,
 890                 .procname       = "overflowuid",
 891                 .data           = &fs_overflowuid,
 892                 .maxlen         = sizeof(int),
 893                 .mode           = 0644,
 894                 .proc_handler   = &proc_dointvec_minmax,
 895                 .strategy       = &sysctl_intvec,
 896                 .extra1         = &minolduid,
 897                 .extra2         = &maxolduid,
 898         },
 899         {
 900                 .ctl_name       = FS_OVERFLOWGID,
 901                 .procname       = "overflowgid",
 902                 .data           = &fs_overflowgid,
 903                 .maxlen         = sizeof(int),
 904                 .mode           = 0644,
 905                 .proc_handler   = &proc_dointvec_minmax,
 906                 .strategy       = &sysctl_intvec,
 907                 .extra1         = &minolduid,
 908                 .extra2         = &maxolduid,
 909         },
 910         {
 911                 .ctl_name       = FS_LEASES,
 912                 .procname       = "leases-enable",
 913                 .data           = &leases_enable,
 914                 .maxlen         = sizeof(int),
 915                 .mode           = 0644,
 916                 .proc_handler   = &proc_dointvec,
 917         },
 918 #ifdef CONFIG_DNOTIFY
 919         {
 920                 .ctl_name       = FS_DIR_NOTIFY,
 921                 .procname       = "dir-notify-enable",
 922                 .data           = &dir_notify_enable,
 923                 .maxlen         = sizeof(int),
 924                 .mode           = 0644,
 925                 .proc_handler   = &proc_dointvec,
 926         },
 927 #endif
 928 #ifdef CONFIG_MMU
 929         {
 930                 .ctl_name       = FS_LEASE_TIME,
 931                 .procname       = "lease-break-time",
 932                 .data           = &lease_break_time,
 933                 .maxlen         = sizeof(int),
 934                 .mode           = 0644,
 935                 .proc_handler   = &proc_dointvec,
 936         },
 937         {
 938                 .ctl_name       = FS_AIO_NR,
 939                 .procname       = "aio-nr",
 940                 .data           = &aio_nr,
 941                 .maxlen         = sizeof(aio_nr),
 942                 .mode           = 0444,
 943                 .proc_handler   = &proc_dointvec,
 944         },
 945         {
 946                 .ctl_name       = FS_AIO_MAX_NR,
 947                 .procname       = "aio-max-nr",
 948                 .data           = &aio_max_nr,
 949                 .maxlen         = sizeof(aio_max_nr),
 950                 .mode           = 0644,
 951                 .proc_handler   = &proc_dointvec,
 952         },
 953 #endif
 954         {
 955                 .ctl_name       = KERN_SETUID_DUMPABLE,
 956                 .procname       = "suid_dumpable",
 957                 .data           = &suid_dumpable,
 958                 .maxlen         = sizeof(int),
 959                 .mode           = 0644,
 960                 .proc_handler   = &proc_dointvec,
 961         },
 962         { .ctl_name = 0 }
 963 };
 964
 965 static ctl_table debug_table[] = {
 966         { .ctl_name = 0 }
 967 };
 968
 969 static ctl_table dev_table[] = {
 970         { .ctl_name = 0 }
 971 };
 972
 973 extern void init_irq_proc (void);
 974
 975 void __init sysctl_init(void)
 976 {
 977 #ifdef CONFIG_PROC_FS
 978         register_proc_table(root_table, proc_sys_root);
 979         init_irq_proc();
 980 #endif
 981 }
 982
 983 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
 984                void __user *newval, size_t newlen)
 985 {
 986         struct list_head *tmp;
 987
 988         if (nlen <= 0 || nlen >= CTL_MAXNAME)
 989                 return -ENOTDIR;
 990         if (oldval) {
 991                 int old_len;
 992                 if (!oldlenp || get_user(old_len, oldlenp))
 993                         return -EFAULT;
 994         }
 995         tmp = &root_table_header.ctl_entry;
 996         do {
 997                 struct ctl_table_header *head =
 998                         list_entry(tmp, struct ctl_table_header, ctl_entry);
 999                 void *context = NULL;
1000                 int error = parse_table(name, nlen, oldval, oldlenp,
1001                                         newval, newlen, head->ctl_table,
1002                                         &context);
1003                 if (context)
1004                         kfree(context);
1005                 if (error != -ENOTDIR)
1006                         return error;
1007                 tmp = tmp->next;
1008         } while (tmp != &root_table_header.ctl_entry);
1009         return -ENOTDIR;
1010 }
1011
1012 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1013 {
1014         struct __sysctl_args tmp;
1015         int error;
1016
1017         if (copy_from_user(&tmp, args, sizeof(tmp)))
1018                 return -EFAULT;
1019
1020         lock_kernel();
1021         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1022                           tmp.newval, tmp.newlen);
1023         unlock_kernel();
1024         return error;
1025 }
1026
1027 /*
1028  * ctl_perm does NOT grant the superuser all rights automatically, because
1029  * some sysctl variables are readonly even to root.
1030  */
1031
1032 static int test_perm(int mode, int op)
1033 {
1034         if (!current->euid)
1035                 mode >>= 6;
1036         else if (in_egroup_p(0))
1037                 mode >>= 3;
1038         if ((mode & op & 0007) == op)
1039                 return 0;
1040         return -EACCES;
1041 }
1042
1043 static inline int ctl_perm(ctl_table *table, int op)
1044 {
1045         int error;
1046         error = security_sysctl(table, op);
1047         if (error)
1048                 return error;
1049         return test_perm(table->mode, op);
1050 }
1051
1052 static int parse_table(int __user *name, int nlen,
1053                        void __user *oldval, size_t __user *oldlenp,
1054                        void __user *newval, size_t newlen,
1055                        ctl_table *table, void **context)
1056 {
1057         int n;
1058 repeat:
1059         if (!nlen)
1060                 return -ENOTDIR;
1061         if (get_user(n, name))
1062                 return -EFAULT;
1063         for ( ; table->ctl_name; table++) {
1064                 if (n == table->ctl_name || table->ctl_name == CTL_ANY) {
1065                         int error;
1066                         if (table->child) {
1067                                 if (ctl_perm(table, 001))
1068                                         return -EPERM;
1069                                 if (table->strategy) {
1070                                         error = table->strategy(
1071                                                 table, name, nlen,
1072                                                 oldval, oldlenp,
1073                                                 newval, newlen, context);
1074                                         if (error)
1075                                                 return error;
1076                                 }
1077                                 name++;
1078                                 nlen--;
1079                                 table = table->child;
1080                                 goto repeat;
1081                         }
1082                         error = do_sysctl_strategy(table, name, nlen,
1083                                                    oldval, oldlenp,
1084                                                    newval, newlen, context);
1085                         return error;
1086                 }
1087         }
1088         return -ENOTDIR;
1089 }
1090
1091 /* Perform the actual read/write of a sysctl table entry. */
1092 int do_sysctl_strategy (ctl_table *table,
1093                         int __user *name, int nlen,
1094                         void __user *oldval, size_t __user *oldlenp,
1095                         void __user *newval, size_t newlen, void **context)
1096 {
1097         int op = 0, rc;
1098         size_t len;
1099
1100         if (oldval)
1101                 op |= 004;
1102         if (newval)
1103                 op |= 002;
1104         if (ctl_perm(table, op))
1105                 return -EPERM;
1106
1107         if (table->strategy) {
1108                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1109                                      newval, newlen, context);
1110                 if (rc < 0)
1111                         return rc;
1112                 if (rc > 0)
1113                         return 0;
1114         }
1115
1116         /* If there is no strategy routine, or if the strategy returns
1117          * zero, proceed with automatic r/w */
1118         if (table->data && table->maxlen) {
1119                 if (oldval && oldlenp) {
1120                         if (get_user(len, oldlenp))
1121                                 return -EFAULT;
1122                         if (len) {
1123                                 if (len > table->maxlen)
1124                                         len = table->maxlen;
1125                                 if(copy_to_user(oldval, table->data, len))
1126                                         return -EFAULT;
1127                                 if(put_user(len, oldlenp))
1128                                         return -EFAULT;
1129                         }
1130                 }
1131                 if (newval && newlen) {
1132                         len = newlen;
1133                         if (len > table->maxlen)
1134                                 len = table->maxlen;
1135                         if(copy_from_user(table->data, newval, len))
1136                                 return -EFAULT;
1137                 }
1138         }
1139         return 0;
1140 }
1141
1142 /**
1143  * register_sysctl_table - register a sysctl hierarchy
1144  * @table: the top-level table structure
1145  * @insert_at_head: whether the entry should be inserted in front or at the end
1146  *
1147  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1148  * array. An entry with a ctl_name of 0 terminates the table.
1149  *
1150  * The members of the &ctl_table structure are used as follows:
1151  *
1152  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1153  *            must be unique within that level of sysctl
1154  *
1155  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1156  *            enter a sysctl file
1157  *
1158  * data - a pointer to data for use by proc_handler
1159  *
1160  * maxlen - the maximum size in bytes of the data
1161  *
1162  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1163  *
1164  * child - a pointer to the child sysctl table if this entry is a directory, or
1165  *         %NULL.
1166  *
1167  * proc_handler - the text handler routine (described below)
1168  *
1169  * strategy - the strategy routine (described below)
1170  *
1171  * de - for internal use by the sysctl routines
1172  *
1173  * extra1, extra2 - extra pointers usable by the proc handler routines
1174  *
1175  * Leaf nodes in the sysctl tree will be represented by a single file
1176  * under /proc; non-leaf nodes will be represented by directories.
1177  *
1178  * sysctl(2) can automatically manage read and write requests through
1179  * the sysctl table.  The data and maxlen fields of the ctl_table
1180  * struct enable minimal validation of the values being written to be
1181  * performed, and the mode field allows minimal authentication.
1182  *
1183  * More sophisticated management can be enabled by the provision of a
1184  * strategy routine with the table entry.  This will be called before
1185  * any automatic read or write of the data is performed.
1186  *
1187  * The strategy routine may return
1188  *
1189  * < 0 - Error occurred (error is passed to user process)
1190  *
1191  * 0   - OK - proceed with automatic read or write.
1192  *
1193  * > 0 - OK - read or write has been done by the strategy routine, so
1194  *       return immediately.
1195  *
1196  * There must be a proc_handler routine for any terminal nodes
1197  * mirrored under /proc/sys (non-terminals are handled by a built-in
1198  * directory handler).  Several default handlers are available to
1199  * cover common cases -
1200  *
1201  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1202  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1203  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1204  *
1205  * It is the handler's job to read the input buffer from user memory
1206  * and process it. The handler should return 0 on success.
1207  *
1208  * This routine returns %NULL on a failure to register, and a pointer
1209  * to the table header on success.
1210  */
1211 struct ctl_table_header *register_sysctl_table(ctl_table * table,
1212                                                int insert_at_head)
1213 {
1214         struct ctl_table_header *tmp;
1215         tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1216         if (!tmp)
1217                 return NULL;
1218         tmp->ctl_table = table;
1219         INIT_LIST_HEAD(&tmp->ctl_entry);
1220         if (insert_at_head)
1221                 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
1222         else
1223                 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1224 #ifdef CONFIG_PROC_FS
1225         register_proc_table(table, proc_sys_root);
1226 #endif
1227         return tmp;
1228 }
1229
1230 /**
1231  * unregister_sysctl_table - unregister a sysctl table hierarchy
1232  * @header: the header returned from register_sysctl_table
1233  *
1234  * Unregisters the sysctl table and all children. proc entries may not
1235  * actually be removed until they are no longer used by anyone.
1236  */
1237 void unregister_sysctl_table(struct ctl_table_header * header)
1238 {
1239         list_del(&header->ctl_entry);
1240 #ifdef CONFIG_PROC_FS
1241         unregister_proc_table(header->ctl_table, proc_sys_root);
1242 #endif
1243         kfree(header);
1244 }
1245
1246 /*
1247  * /proc/sys support
1248  */
1249
1250 #ifdef CONFIG_PROC_FS
1251
1252 /* Scan the sysctl entries in table and add them all into /proc */
1253 static void register_proc_table(ctl_table * table, struct proc_dir_entry *root)
1254 {
1255         struct proc_dir_entry *de;
1256         int len;
1257         mode_t mode;
1258
1259         for (; table->ctl_name; table++) {
1260                 /* Can't do anything without a proc name. */
1261                 if (!table->procname)
1262                         continue;
1263                 /* Maybe we can't do anything with it... */
1264                 if (!table->proc_handler && !table->child) {
1265                         printk(KERN_WARNING "SYSCTL: Can't register %s\n",
1266                                 table->procname);
1267                         continue;
1268                 }
1269
1270                 len = strlen(table->procname);
1271                 mode = table->mode;
1272
1273                 de = NULL;
1274                 if (table->proc_handler)
1275                         mode |= S_IFREG;
1276                 else {
1277                         mode |= S_IFDIR;
1278                         for (de = root->subdir; de; de = de->next) {
1279                                 if (proc_match(len, table->procname, de))
1280                                         break;
1281                         }
1282                         /* If the subdir exists already, de is non-NULL */
1283                 }
1284
1285                 if (!de) {
1286                         de = create_proc_entry(table->procname, mode, root);
1287                         if (!de)
1288                                 continue;
1289                         de->data = (void *) table;
1290                         if (table->proc_handler)
1291                                 de->proc_fops = &proc_sys_file_operations;
1292                 }
1293                 table->de = de;
1294                 if (de->mode & S_IFDIR)
1295                         register_proc_table(table->child, de);
1296         }
1297 }
1298
1299 /*
1300  * Unregister a /proc sysctl table and any subdirectories.
1301  */
1302 static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
1303 {
1304         struct proc_dir_entry *de;
1305         for (; table->ctl_name; table++) {
1306                 if (!(de = table->de))
1307                         continue;
1308                 if (de->mode & S_IFDIR) {
1309                         if (!table->child) {
1310                                 printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
1311                                 continue;
1312                         }
1313                         unregister_proc_table(table->child, de);
1314
1315                         /* Don't unregister directories which still have entries.. */
1316                         if (de->subdir)
1317                                 continue;
1318                 }
1319
1320                 /* Don't unregister proc entries that are still being used.. */
1321                 if (atomic_read(&de->count))
1322                         continue;
1323
1324                 table->de = NULL;
1325                 remove_proc_entry(table->procname, root);
1326         }
1327 }
1328
1329 static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
1330                           size_t count, loff_t *ppos)
1331 {
1332         int op;
1333         struct proc_dir_entry *de;
1334         struct ctl_table *table;
1335         size_t res;
1336         ssize_t error;
1337
1338         de = PDE(file->f_dentry->d_inode);
1339         if (!de || !de->data)
1340                 return -ENOTDIR;
1341         table = (struct ctl_table *) de->data;
1342         if (!table || !table->proc_handler)
1343                 return -ENOTDIR;
1344         op = (write ? 002 : 004);
1345         if (ctl_perm(table, op))
1346                 return -EPERM;
1347
1348         res = count;
1349
1350         error = (*table->proc_handler) (table, write, file, buf, &res, ppos);
1351         if (error)
1352                 return error;
1353         return res;
1354 }
1355
1356 static int proc_opensys(struct inode *inode, struct file *file)
1357 {
1358         if (file->f_mode & FMODE_WRITE) {
1359                 /*
1360                  * sysctl entries that are not writable,
1361                  * are _NOT_ writable, capabilities or not.
1362                  */
1363                 if (!(inode->i_mode & S_IWUSR))
1364                         return -EPERM;
1365         }
1366
1367         return 0;
1368 }
1369
1370 static ssize_t proc_readsys(struct file * file, char __user * buf,
1371                             size_t count, loff_t *ppos)
1372 {
1373         return do_rw_proc(0, file, buf, count, ppos);
1374 }
1375
1376 static ssize_t proc_writesys(struct file * file, const char __user * buf,
1377                              size_t count, loff_t *ppos)
1378 {
1379         return do_rw_proc(1, file, (char __user *) buf, count, ppos);
1380 }
1381
1382 /**
1383  * proc_dostring - read a string sysctl
1384  * @table: the sysctl table
1385  * @write: %TRUE if this is a write to the sysctl file
1386  * @filp: the file structure
1387  * @buffer: the user buffer
1388  * @lenp: the size of the user buffer
1389  * @ppos: file position
1390  *
1391  * Reads/writes a string from/to the user buffer. If the kernel
1392  * buffer provided is not large enough to hold the string, the
1393  * string is truncated. The copied string is %NULL-terminated.
1394  * If the string is being read by the user process, it is copied
1395  * and a newline '\n' is added. It is truncated if the buffer is
1396  * not large enough.
1397  *
1398  * Returns 0 on success.
1399  */
1400 int proc_dostring(ctl_table *table, int write, struct file *filp,
1401                   void __user *buffer, size_t *lenp, loff_t *ppos)
1402 {
1403         size_t len;
1404         char __user *p;
1405         char c;
1406
1407         if (!table->data || !table->maxlen || !*lenp ||
1408             (*ppos && !write)) {
1409                 *lenp = 0;
1410                 return 0;
1411         }
1412
1413         if (write) {
1414                 len = 0;
1415                 p = buffer;
1416                 while (len < *lenp) {
1417                         if (get_user(c, p++))
1418                                 return -EFAULT;
1419                         if (c == 0 || c == '\n')
1420                                 break;
1421                         len++;
1422                 }
1423                 if (len >= table->maxlen)
1424                         len = table->maxlen-1;
1425                 if(copy_from_user(table->data, buffer, len))
1426                         return -EFAULT;
1427                 ((char *) table->data)[len] = 0;
1428                 *ppos += *lenp;
1429         } else {
1430                 len = strlen(table->data);
1431                 if (len > table->maxlen)
1432                         len = table->maxlen;
1433                 if (len > *lenp)
1434                         len = *lenp;
1435                 if (len)
1436                         if(copy_to_user(buffer, table->data, len))
1437                                 return -EFAULT;
1438                 if (len < *lenp) {
1439                         if(put_user('\n', ((char __user *) buffer) + len))
1440                                 return -EFAULT;
1441                         len++;
1442                 }
1443                 *lenp = len;
1444                 *ppos += len;
1445         }
1446         return 0;
1447 }
1448
1449 /*
1450  *      Special case of dostring for the UTS structure. This has locks
1451  *      to observe. Should this be in kernel/sys.c ????
1452  */
1453
1454 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
1455                   void __user *buffer, size_t *lenp, loff_t *ppos)
1456 {
1457         int r;
1458
1459         if (!write) {
1460                 down_read(&uts_sem);
1461                 r=proc_dostring(table,0,filp,buffer,lenp, ppos);
1462                 up_read(&uts_sem);
1463         } else {
1464                 down_write(&uts_sem);
1465                 r=proc_dostring(table,1,filp,buffer,lenp, ppos);
1466                 up_write(&uts_sem);
1467         }
1468         return r;
1469 }
1470
1471 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1472                                  int *valp,
1473                                  int write, void *data)
1474 {
1475         if (write) {
1476                 *valp = *negp ? -*lvalp : *lvalp;
1477         } else {
1478                 int val = *valp;
1479                 if (val < 0) {
1480                         *negp = -1;
1481                         *lvalp = (unsigned long)-val;
1482                 } else {
1483                         *negp = 0;
1484                         *lvalp = (unsigned long)val;
1485                 }
1486         }
1487         return 0;
1488 }
1489
1490 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1491                   void __user *buffer, size_t *lenp, loff_t *ppos,
1492                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1493                               int write, void *data),
1494                   void *data)
1495 {
1496 #define TMPBUFLEN 21
1497         int *i, vleft, first=1, neg, val;
1498         unsigned long lval;
1499         size_t left, len;
1500
1501         char buf[TMPBUFLEN], *p;
1502         char __user *s = buffer;
1503
1504         if (!table->data || !table->maxlen || !*lenp ||
1505             (*ppos && !write)) {
1506                 *lenp = 0;
1507                 return 0;
1508         }
1509
1510         i = (int *) table->data;
1511         vleft = table->maxlen / sizeof(*i);
1512         left = *lenp;
1513
1514         if (!conv)
1515                 conv = do_proc_dointvec_conv;
1516
1517         for (; left && vleft--; i++, first=0) {
1518                 if (write) {
1519                         while (left) {
1520                                 char c;
1521                                 if (get_user(c, s))
1522                                         return -EFAULT;
1523                                 if (!isspace(c))
1524                                         break;
1525                                 left--;
1526                                 s++;
1527                         }
1528                         if (!left)
1529                                 break;
1530                         neg = 0;
1531                         len = left;
1532                         if (len > sizeof(buf) - 1)
1533                                 len = sizeof(buf) - 1;
1534                         if (copy_from_user(buf, s, len))
1535                                 return -EFAULT;
1536                         buf[len] = 0;
1537                         p = buf;
1538                         if (*p == '-' && left > 1) {
1539                                 neg = 1;
1540                                 left--, p++;
1541                         }
1542                         if (*p < '0' || *p > '9')
1543                                 break;
1544
1545                         lval = simple_strtoul(p, &p, 0);
1546
1547                         len = p-buf;
1548                         if ((len < left) && *p && !isspace(*p))
1549                                 break;
1550                         if (neg)
1551                                 val = -val;
1552                         s += len;
1553                         left -= len;
1554
1555                         if (conv(&neg, &lval, i, 1, data))
1556                                 break;
1557                 } else {
1558                         p = buf;
1559                         if (!first)
1560                                 *p++ = '\t';
1561
1562                         if (conv(&neg, &lval, i, 0, data))
1563                                 break;
1564
1565                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
1566                         len = strlen(buf);
1567                         if (len > left)
1568                                 len = left;
1569                         if(copy_to_user(s, buf, len))
1570                                 return -EFAULT;
1571                         left -= len;
1572                         s += len;
1573                 }
1574         }
1575
1576         if (!write && !first && left) {
1577                 if(put_user('\n', s))
1578                         return -EFAULT;
1579                 left--, s++;
1580         }
1581         if (write) {
1582                 while (left) {
1583                         char c;
1584                         if (get_user(c, s++))
1585                                 return -EFAULT;
1586                         if (!isspace(c))
1587                                 break;
1588                         left--;
1589                 }
1590         }
1591         if (write && first)
1592                 return -EINVAL;
1593         *lenp -= left;
1594         *ppos += *lenp;
1595         return 0;
1596 #undef TMPBUFLEN
1597 }
1598
1599 /**
1600  * proc_dointvec - read a vector of integers
1601  * @table: the sysctl table
1602  * @write: %TRUE if this is a write to the sysctl file
1603  * @filp: the file structure
1604  * @buffer: the user buffer
1605  * @lenp: the size of the user buffer
1606  * @ppos: file position
1607  *
1608  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1609  * values from/to the user buffer, treated as an ASCII string.
1610  *
1611  * Returns 0 on success.
1612  */
1613 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1614                      void __user *buffer, size_t *lenp, loff_t *ppos)
1615 {
1616     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1617                             NULL,NULL);
1618 }
1619
1620 #define OP_SET  0
1621 #define OP_AND  1
1622 #define OP_OR   2
1623 #define OP_MAX  3
1624 #define OP_MIN  4
1625
1626 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1627                                       int *valp,
1628                                       int write, void *data)
1629 {
1630         int op = *(int *)data;
1631         if (write) {
1632                 int val = *negp ? -*lvalp : *lvalp;
1633                 switch(op) {
1634                 case OP_SET:    *valp = val; break;
1635                 case OP_AND:    *valp &= val; break;
1636                 case OP_OR:     *valp |= val; break;
1637                 case OP_MAX:    if(*valp < val)
1638                                         *valp = val;
1639                                 break;
1640                 case OP_MIN:    if(*valp > val)
1641                                 *valp = val;
1642                                 break;
1643                 }
1644         } else {
1645                 int val = *valp;
1646                 if (val < 0) {
1647                         *negp = -1;
1648                         *lvalp = (unsigned long)-val;
1649                 } else {
1650                         *negp = 0;
1651                         *lvalp = (unsigned long)val;
1652                 }
1653         }
1654         return 0;
1655 }
1656
1657 /*
1658  *      init may raise the set.
1659  */
1660
1661 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1662                         void __user *buffer, size_t *lenp, loff_t *ppos)
1663 {
1664         int op;
1665
1666         if (!capable(CAP_SYS_MODULE)) {
1667                 return -EPERM;
1668         }
1669
1670         op = (current->pid == 1) ? OP_SET : OP_AND;
1671         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1672                                 do_proc_dointvec_bset_conv,&op);
1673 }
1674
1675 struct do_proc_dointvec_minmax_conv_param {
1676         int *min;
1677         int *max;
1678 };
1679
1680 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1681                                         int *valp,
1682                                         int write, void *data)
1683 {
1684         struct do_proc_dointvec_minmax_conv_param *param = data;
1685         if (write) {
1686                 int val = *negp ? -*lvalp : *lvalp;
1687                 if ((param->min && *param->min > val) ||
1688                     (param->max && *param->max < val))
1689                         return -EINVAL;
1690                 *valp = val;
1691         } else {
1692                 int val = *valp;
1693                 if (val < 0) {
1694                         *negp = -1;
1695                         *lvalp = (unsigned long)-val;
1696                 } else {
1697                         *negp = 0;
1698                         *lvalp = (unsigned long)val;
1699                 }
1700         }
1701         return 0;
1702 }
1703
1704 /**
1705  * proc_dointvec_minmax - read a vector of integers with min/max values
1706  * @table: the sysctl table
1707  * @write: %TRUE if this is a write to the sysctl file
1708  * @filp: the file structure
1709  * @buffer: the user buffer
1710  * @lenp: the size of the user buffer
1711  * @ppos: file position
1712  *
1713  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1714  * values from/to the user buffer, treated as an ASCII string.
1715  *
1716  * This routine will ensure the values are within the range specified by
1717  * table->extra1 (min) and table->extra2 (max).
1718  *
1719  * Returns 0 on success.
1720  */
1721 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1722                   void __user *buffer, size_t *lenp, loff_t *ppos)
1723 {
1724         struct do_proc_dointvec_minmax_conv_param param = {
1725                 .min = (int *) table->extra1,
1726                 .max = (int *) table->extra2,
1727         };
1728         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1729                                 do_proc_dointvec_minmax_conv, &param);
1730 }
1731
1732 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1733                                      struct file *filp,
1734                                      void __user *buffer,
1735                                      size_t *lenp, loff_t *ppos,
1736                                      unsigned long convmul,
1737                                      unsigned long convdiv)
1738 {
1739 #define TMPBUFLEN 21
1740         unsigned long *i, *min, *max, val;
1741         int vleft, first=1, neg;
1742         size_t len, left;
1743         char buf[TMPBUFLEN], *p;
1744         char __user *s = buffer;
1745
1746         if (!table->data || !table->maxlen || !*lenp ||
1747             (*ppos && !write)) {
1748                 *lenp = 0;
1749                 return 0;
1750         }
1751
1752         i = (unsigned long *) table->data;
1753         min = (unsigned long *) table->extra1;
1754         max = (unsigned long *) table->extra2;
1755         vleft = table->maxlen / sizeof(unsigned long);
1756         left = *lenp;
1757
1758         for (; left && vleft--; i++, min++, max++, first=0) {
1759                 if (write) {
1760                         while (left) {
1761                                 char c;
1762                                 if (get_user(c, s))
1763                                         return -EFAULT;
1764                                 if (!isspace(c))
1765                                         break;
1766                                 left--;
1767                                 s++;
1768                         }
1769                         if (!left)
1770                                 break;
1771                         neg = 0;
1772                         len = left;
1773                         if (len > TMPBUFLEN-1)
1774                                 len = TMPBUFLEN-1;
1775                         if (copy_from_user(buf, s, len))
1776                                 return -EFAULT;
1777                         buf[len] = 0;
1778                         p = buf;
1779                         if (*p == '-' && left > 1) {
1780                                 neg = 1;
1781                                 left--, p++;
1782                         }
1783                         if (*p < '0' || *p > '9')
1784                                 break;
1785                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1786                         len = p-buf;
1787                         if ((len < left) && *p && !isspace(*p))
1788                                 break;
1789                         if (neg)
1790                                 val = -val;
1791                         s += len;
1792                         left -= len;
1793
1794                         if(neg)
1795                                 continue;
1796                         if ((min && val < *min) || (max && val > *max))
1797                                 continue;
1798                         *i = val;
1799                 } else {
1800                         p = buf;
1801                         if (!first)
1802                                 *p++ = '\t';
1803                         sprintf(p, "%lu", convdiv * (*i) / convmul);
1804                         len = strlen(buf);
1805                         if (len > left)
1806                                 len = left;
1807                         if(copy_to_user(s, buf, len))
1808                                 return -EFAULT;
1809                         left -= len;
1810                         s += len;
1811                 }
1812         }
1813
1814         if (!write && !first && left) {
1815                 if(put_user('\n', s))
1816                         return -EFAULT;
1817                 left--, s++;
1818         }
1819         if (write) {
1820                 while (left) {
1821                         char c;
1822                         if (get_user(c, s++))
1823                                 return -EFAULT;
1824                         if (!isspace(c))
1825                                 break;
1826                         left--;
1827                 }
1828         }
1829         if (write && first)
1830                 return -EINVAL;
1831         *lenp -= left;
1832         *ppos += *lenp;
1833         return 0;
1834 #undef TMPBUFLEN
1835 }
1836
1837 /**
1838  * proc_doulongvec_minmax - read a vector of long integers with min/max values
1839  * @table: the sysctl table
1840  * @write: %TRUE if this is a write to the sysctl file
1841  * @filp: the file structure
1842  * @buffer: the user buffer
1843  * @lenp: the size of the user buffer
1844  * @ppos: file position
1845  *
1846  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1847  * values from/to the user buffer, treated as an ASCII string.
1848  *
1849  * This routine will ensure the values are within the range specified by
1850  * table->extra1 (min) and table->extra2 (max).
1851  *
1852  * Returns 0 on success.
1853  */
1854 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
1855                            void __user *buffer, size_t *lenp, loff_t *ppos)
1856 {
1857     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
1858 }
1859
1860 /**
1861  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
1862  * @table: the sysctl table
1863  * @write: %TRUE if this is a write to the sysctl file
1864  * @filp: the file structure
1865  * @buffer: the user buffer
1866  * @lenp: the size of the user buffer
1867  * @ppos: file position
1868  *
1869  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1870  * values from/to the user buffer, treated as an ASCII string. The values
1871  * are treated as milliseconds, and converted to jiffies when they are stored.
1872  *
1873  * This routine will ensure the values are within the range specified by
1874  * table->extra1 (min) and table->extra2 (max).
1875  *
1876  * Returns 0 on success.
1877  */
1878 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
1879                                       struct file *filp,
1880                                       void __user *buffer,
1881                                       size_t *lenp, loff_t *ppos)
1882 {
1883     return do_proc_doulongvec_minmax(table, write, filp, buffer,
1884                                      lenp, ppos, HZ, 1000l);
1885 }
1886
1887
1888 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
1889                                          int *valp,
1890                                          int write, void *data)
1891 {
1892         if (write) {
1893                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
1894         } else {
1895                 int val = *valp;
1896                 unsigned long lval;
1897                 if (val < 0) {
1898                         *negp = -1;
1899                         lval = (unsigned long)-val;
1900                 } else {
1901                         *negp = 0;
1902                         lval = (unsigned long)val;
1903                 }
1904                 *lvalp = lval / HZ;
1905         }
1906         return 0;
1907 }
1908
1909 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
1910                                                 int *valp,
1911                                                 int write, void *data)
1912 {
1913         if (write) {
1914                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
1915         } else {
1916                 int val = *valp;
1917                 unsigned long lval;
1918                 if (val < 0) {
1919                         *negp = -1;
1920                         lval = (unsigned long)-val;
1921                 } else {
1922                         *negp = 0;
1923                         lval = (unsigned long)val;
1924                 }
1925                 *lvalp = jiffies_to_clock_t(lval);
1926         }
1927         return 0;
1928 }
1929
1930 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
1931                                             int *valp,
1932                                             int write, void *data)
1933 {
1934         if (write) {
1935                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
1936         } else {
1937                 int val = *valp;
1938                 unsigned long lval;
1939                 if (val < 0) {
1940                         *negp = -1;
1941                         lval = (unsigned long)-val;
1942                 } else {
1943                         *negp = 0;
1944                         lval = (unsigned long)val;
1945                 }
1946                 *lvalp = jiffies_to_msecs(lval);
1947         }
1948         return 0;
1949 }
1950
1951 /**
1952  * proc_dointvec_jiffies - read a vector of integers as seconds
1953  * @table: the sysctl table
1954  * @write: %TRUE if this is a write to the sysctl file
1955  * @filp: the file structure
1956  * @buffer: the user buffer
1957  * @lenp: the size of the user buffer
1958  * @ppos: file position
1959  *
1960  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1961  * values from/to the user buffer, treated as an ASCII string.
1962  * The values read are assumed to be in seconds, and are converted into
1963  * jiffies.
1964  *
1965  * Returns 0 on success.
1966  */
1967 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
1968                           void __user *buffer, size_t *lenp, loff_t *ppos)
1969 {
1970     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1971                             do_proc_dointvec_jiffies_conv,NULL);
1972 }
1973
1974 /**
1975  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
1976  * @table: the sysctl table
1977  * @write: %TRUE if this is a write to the sysctl file
1978  * @filp: the file structure
1979  * @buffer: the user buffer
1980  * @lenp: the size of the user buffer
1981  *
1982  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1983  * values from/to the user buffer, treated as an ASCII string.
1984  * The values read are assumed to be in 1/USER_HZ seconds, and
1985  * are converted into jiffies.
1986  *
1987  * Returns 0 on success.
1988  */
1989 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
1990                                  void __user *buffer, size_t *lenp, loff_t *ppos)
1991 {
1992     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1993                             do_proc_dointvec_userhz_jiffies_conv,NULL);
1994 }
1995
1996 /**
1997  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
1998  * @table: the sysctl table
1999  * @write: %TRUE if this is a write to the sysctl file
2000  * @filp: the file structure
2001  * @buffer: the user buffer
2002  * @lenp: the size of the user buffer
2003  * @ppos: file position
2004  * @ppos: the current position in the file
2005  *
2006  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2007  * values from/to the user buffer, treated as an ASCII string.
2008  * The values read are assumed to be in 1/1000 seconds, and
2009  * are converted into jiffies.
2010  *
2011  * Returns 0 on success.
2012  */
2013 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2014                              void __user *buffer, size_t *lenp, loff_t *ppos)
2015 {
2016         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2017                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2018 }
2019
2020 #else /* CONFIG_PROC_FS */
2021
2022 int proc_dostring(ctl_table *table, int write, struct file *filp,
2023                   void __user *buffer, size_t *lenp, loff_t *ppos)
2024 {
2025         return -ENOSYS;
2026 }
2027
2028 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
2029                             void __user *buffer, size_t *lenp, loff_t *ppos)
2030 {
2031         return -ENOSYS;
2032 }
2033
2034 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2035                   void __user *buffer, size_t *lenp, loff_t *ppos)
2036 {
2037         return -ENOSYS;
2038 }
2039
2040 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2041                         void __user *buffer, size_t *lenp, loff_t *ppos)
2042 {
2043         return -ENOSYS;
2044 }
2045
2046 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2047                     void __user *buffer, size_t *lenp, loff_t *ppos)
2048 {
2049         return -ENOSYS;
2050 }
2051
2052 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2053                     void __user *buffer, size_t *lenp, loff_t *ppos)
2054 {
2055         return -ENOSYS;
2056 }
2057
2058 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2059                     void __user *buffer, size_t *lenp, loff_t *ppos)
2060 {
2061         return -ENOSYS;
2062 }
2063
2064 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2065                              void __user *buffer, size_t *lenp, loff_t *ppos)
2066 {
2067         return -ENOSYS;
2068 }
2069
2070 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2071                     void __user *buffer, size_t *lenp, loff_t *ppos)
2072 {
2073         return -ENOSYS;
2074 }
2075
2076 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2077                                       struct file *filp,
2078                                       void __user *buffer,
2079                                       size_t *lenp, loff_t *ppos)
2080 {
2081     return -ENOSYS;
2082 }
2083
2084
2085 #endif /* CONFIG_PROC_FS */
2086
2087
2088 /*
2089  * General sysctl support routines
2090  */
2091
2092 /* The generic string strategy routine: */
2093 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2094                   void __user *oldval, size_t __user *oldlenp,
2095                   void __user *newval, size_t newlen, void **context)
2096 {
2097         size_t l, len;
2098
2099         if (!table->data || !table->maxlen)
2100                 return -ENOTDIR;
2101
2102         if (oldval && oldlenp) {
2103                 if (get_user(len, oldlenp))
2104                         return -EFAULT;
2105                 if (len) {
2106                         l = strlen(table->data);
2107                         if (len > l) len = l;
2108                         if (len >= table->maxlen)
2109                                 len = table->maxlen;
2110                         if(copy_to_user(oldval, table->data, len))
2111                                 return -EFAULT;
2112                         if(put_user(0, ((char __user *) oldval) + len))
2113                                 return -EFAULT;
2114                         if(put_user(len, oldlenp))
2115                                 return -EFAULT;
2116                 }
2117         }
2118         if (newval && newlen) {
2119                 len = newlen;
2120                 if (len > table->maxlen)
2121                         len = table->maxlen;
2122                 if(copy_from_user(table->data, newval, len))
2123                         return -EFAULT;
2124                 if (len == table->maxlen)
2125                         len--;
2126                 ((char *) table->data)[len] = 0;
2127         }
2128         return 0;
2129 }
2130
2131 /*
2132  * This function makes sure that all of the integers in the vector
2133  * are between the minimum and maximum values given in the arrays
2134  * table->extra1 and table->extra2, respectively.
2135  */
2136 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2137                 void __user *oldval, size_t __user *oldlenp,
2138                 void __user *newval, size_t newlen, void **context)
2139 {
2140
2141         if (newval && newlen) {
2142                 int __user *vec = (int __user *) newval;
2143                 int *min = (int *) table->extra1;
2144                 int *max = (int *) table->extra2;
2145                 size_t length;
2146                 int i;
2147
2148                 if (newlen % sizeof(int) != 0)
2149                         return -EINVAL;
2150
2151                 if (!table->extra1 && !table->extra2)
2152                         return 0;
2153
2154                 if (newlen > table->maxlen)
2155                         newlen = table->maxlen;
2156                 length = newlen / sizeof(int);
2157
2158                 for (i = 0; i < length; i++) {
2159                         int value;
2160                         if (get_user(value, vec + i))
2161                                 return -EFAULT;
2162                         if (min && value < min[i])
2163                                 return -EINVAL;
2164                         if (max && value > max[i])
2165                                 return -EINVAL;
2166                 }
2167         }
2168         return 0;
2169 }
2170
2171 /* Strategy function to convert jiffies to seconds */
2172 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2173                 void __user *oldval, size_t __user *oldlenp,
2174                 void __user *newval, size_t newlen, void **context)
2175 {
2176         if (oldval) {
2177                 size_t olen;
2178                 if (oldlenp) {
2179                         if (get_user(olen, oldlenp))
2180                                 return -EFAULT;
2181                         if (olen!=sizeof(int))
2182                                 return -EINVAL;
2183                 }
2184                 if (put_user(*(int *)(table->data)/HZ, (int __user *)oldval) ||
2185                     (oldlenp && put_user(sizeof(int),oldlenp)))
2186                         return -EFAULT;
2187         }
2188         if (newval && newlen) {
2189                 int new;
2190                 if (newlen != sizeof(int))
2191                         return -EINVAL;
2192                 if (get_user(new, (int __user *)newval))
2193                         return -EFAULT;
2194                 *(int *)(table->data) = new*HZ;
2195         }
2196         return 1;
2197 }
2198
2199 /* Strategy function to convert jiffies to seconds */
2200 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2201                 void __user *oldval, size_t __user *oldlenp,
2202                 void __user *newval, size_t newlen, void **context)
2203 {
2204         if (oldval) {
2205                 size_t olen;
2206                 if (oldlenp) {
2207                         if (get_user(olen, oldlenp))
2208                                 return -EFAULT;
2209                         if (olen!=sizeof(int))
2210                                 return -EINVAL;
2211                 }
2212                 if (put_user(jiffies_to_msecs(*(int *)(table->data)), (int __user *)oldval) ||
2213                     (oldlenp && put_user(sizeof(int),oldlenp)))
2214                         return -EFAULT;
2215         }
2216         if (newval && newlen) {
2217                 int new;
2218                 if (newlen != sizeof(int))
2219                         return -EINVAL;
2220                 if (get_user(new, (int __user *)newval))
2221                         return -EFAULT;
2222                 *(int *)(table->data) = msecs_to_jiffies(new);
2223         }
2224         return 1;
2225 }
2226
2227 #else /* CONFIG_SYSCTL */
2228
2229
2230 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2231 {
2232         return -ENOSYS;
2233 }
2234
2235 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2236                   void __user *oldval, size_t __user *oldlenp,
2237                   void __user *newval, size_t newlen, void **context)
2238 {
2239         return -ENOSYS;
2240 }
2241
2242 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2243                 void __user *oldval, size_t __user *oldlenp,
2244                 void __user *newval, size_t newlen, void **context)
2245 {
2246         return -ENOSYS;
2247 }
2248
2249 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2250                 void __user *oldval, size_t __user *oldlenp,
2251                 void __user *newval, size_t newlen, void **context)
2252 {
2253         return -ENOSYS;
2254 }
2255
2256 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2257                 void __user *oldval, size_t __user *oldlenp,
2258                 void __user *newval, size_t newlen, void **context)
2259 {
2260         return -ENOSYS;
2261 }
2262
2263 int proc_dostring(ctl_table *table, int write, struct file *filp,
2264                   void __user *buffer, size_t *lenp, loff_t *ppos)
2265 {
2266         return -ENOSYS;
2267 }
2268
2269 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2270                   void __user *buffer, size_t *lenp, loff_t *ppos)
2271 {
2272         return -ENOSYS;
2273 }
2274
2275 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2276                         void __user *buffer, size_t *lenp, loff_t *ppos)
2277 {
2278         return -ENOSYS;
2279 }
2280
2281 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2282                     void __user *buffer, size_t *lenp, loff_t *ppos)
2283 {
2284         return -ENOSYS;
2285 }
2286
2287 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2288                           void __user *buffer, size_t *lenp, loff_t *ppos)
2289 {
2290         return -ENOSYS;
2291 }
2292
2293 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2294                           void __user *buffer, size_t *lenp, loff_t *ppos)
2295 {
2296         return -ENOSYS;
2297 }
2298
2299 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2300                              void __user *buffer, size_t *lenp, loff_t *ppos)
2301 {
2302         return -ENOSYS;
2303 }
2304
2305 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2306                     void __user *buffer, size_t *lenp, loff_t *ppos)
2307 {
2308         return -ENOSYS;
2309 }
2310
2311 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2312                                       struct file *filp,
2313                                       void __user *buffer,
2314                                       size_t *lenp, loff_t *ppos)
2315 {
2316     return -ENOSYS;
2317 }
2318
2319 struct ctl_table_header * register_sysctl_table(ctl_table * table,
2320                                                 int insert_at_head)
2321 {
2322         return NULL;
2323 }
2324
2325 void unregister_sysctl_table(struct ctl_table_header * table)
2326 {
2327 }
2328
2329 #endif /* CONFIG_SYSCTL */
2330
2331 /*
2332  * No sense putting this after each symbol definition, twice,
2333  * exception granted :-)
2334  */
2335 EXPORT_SYMBOL(proc_dointvec);
2336 EXPORT_SYMBOL(proc_dointvec_jiffies);
2337 EXPORT_SYMBOL(proc_dointvec_minmax);
2338 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2339 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2340 EXPORT_SYMBOL(proc_dostring);
2341 EXPORT_SYMBOL(proc_doulongvec_minmax);
2342 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2343 EXPORT_SYMBOL(register_sysctl_table);
2344 EXPORT_SYMBOL(sysctl_intvec);
2345 EXPORT_SYMBOL(sysctl_jiffies);
2346 EXPORT_SYMBOL(sysctl_ms_jiffies);
2347 EXPORT_SYMBOL(sysctl_string);
2348 EXPORT_SYMBOL(unregister_sysctl_table);