git.oblomov.eu Git - linux-2.6/blob - 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 #ifdef CONFIG_INOTIFY
 150 extern ctl_table inotify_table[];
 151 #endif
 152
 153 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 154 int sysctl_legacy_va_layout;
 155 #endif
 156
 157 /* /proc declarations: */
 158
 159 #ifdef CONFIG_PROC_FS
 160
 161 static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
 162 static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
 163 static int proc_opensys(struct inode *, struct file *);
 164
 165 struct file_operations proc_sys_file_operations = {
 166         .open           = proc_opensys,
 167         .read           = proc_readsys,
 168         .write          = proc_writesys,
 169 };
 170
 171 extern struct proc_dir_entry *proc_sys_root;
 172
 173 static void register_proc_table(ctl_table *, struct proc_dir_entry *);
 174 static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
 175 #endif
 176
 177 /* The default sysctl tables: */
 178
 179 static ctl_table root_table[] = {
 180         {
 181                 .ctl_name       = CTL_KERN,
 182                 .procname       = "kernel",
 183                 .mode           = 0555,
 184                 .child          = kern_table,
 185         },
 186         {
 187                 .ctl_name       = CTL_VM,
 188                 .procname       = "vm",
 189                 .mode           = 0555,
 190                 .child          = vm_table,
 191         },
 192 #ifdef CONFIG_NET
 193         {
 194                 .ctl_name       = CTL_NET,
 195                 .procname       = "net",
 196                 .mode           = 0555,
 197                 .child          = net_table,
 198         },
 199 #endif
 200         {
 201                 .ctl_name       = CTL_PROC,
 202                 .procname       = "proc",
 203                 .mode           = 0555,
 204                 .child          = proc_table,
 205         },
 206         {
 207                 .ctl_name       = CTL_FS,
 208                 .procname       = "fs",
 209                 .mode           = 0555,
 210                 .child          = fs_table,
 211         },
 212         {
 213                 .ctl_name       = CTL_DEBUG,
 214                 .procname       = "debug",
 215                 .mode           = 0555,
 216                 .child          = debug_table,
 217         },
 218         {
 219                 .ctl_name       = CTL_DEV,
 220                 .procname       = "dev",
 221                 .mode           = 0555,
 222                 .child          = dev_table,
 223         },
 224
 225         { .ctl_name = 0 }
 226 };
 227
 228 static ctl_table kern_table[] = {
 229         {
 230                 .ctl_name       = KERN_OSTYPE,
 231                 .procname       = "ostype",
 232                 .data           = system_utsname.sysname,
 233                 .maxlen         = sizeof(system_utsname.sysname),
 234                 .mode           = 0444,
 235                 .proc_handler   = &proc_doutsstring,
 236                 .strategy       = &sysctl_string,
 237         },
 238         {
 239                 .ctl_name       = KERN_OSRELEASE,
 240                 .procname       = "osrelease",
 241                 .data           = system_utsname.release,
 242                 .maxlen         = sizeof(system_utsname.release),
 243                 .mode           = 0444,
 244                 .proc_handler   = &proc_doutsstring,
 245                 .strategy       = &sysctl_string,
 246         },
 247         {
 248                 .ctl_name       = KERN_VERSION,
 249                 .procname       = "version",
 250                 .data           = system_utsname.version,
 251                 .maxlen         = sizeof(system_utsname.version),
 252                 .mode           = 0444,
 253                 .proc_handler   = &proc_doutsstring,
 254                 .strategy       = &sysctl_string,
 255         },
 256         {
 257                 .ctl_name       = KERN_NODENAME,
 258                 .procname       = "hostname",
 259                 .data           = system_utsname.nodename,
 260                 .maxlen         = sizeof(system_utsname.nodename),
 261                 .mode           = 0644,
 262                 .proc_handler   = &proc_doutsstring,
 263                 .strategy       = &sysctl_string,
 264         },
 265         {
 266                 .ctl_name       = KERN_DOMAINNAME,
 267                 .procname       = "domainname",
 268                 .data           = system_utsname.domainname,
 269                 .maxlen         = sizeof(system_utsname.domainname),
 270                 .mode           = 0644,
 271                 .proc_handler   = &proc_doutsstring,
 272                 .strategy       = &sysctl_string,
 273         },
 274         {
 275                 .ctl_name       = KERN_PANIC,
 276                 .procname       = "panic",
 277                 .data           = &panic_timeout,
 278                 .maxlen         = sizeof(int),
 279                 .mode           = 0644,
 280                 .proc_handler   = &proc_dointvec,
 281         },
 282         {
 283                 .ctl_name       = KERN_CORE_USES_PID,
 284                 .procname       = "core_uses_pid",
 285                 .data           = &core_uses_pid,
 286                 .maxlen         = sizeof(int),
 287                 .mode           = 0644,
 288                 .proc_handler   = &proc_dointvec,
 289         },
 290         {
 291                 .ctl_name       = KERN_CORE_PATTERN,
 292                 .procname       = "core_pattern",
 293                 .data           = core_pattern,
 294                 .maxlen         = 64,
 295                 .mode           = 0644,
 296                 .proc_handler   = &proc_dostring,
 297                 .strategy       = &sysctl_string,
 298         },
 299         {
 300                 .ctl_name       = KERN_TAINTED,
 301                 .procname       = "tainted",
 302                 .data           = &tainted,
 303                 .maxlen         = sizeof(int),
 304                 .mode           = 0444,
 305                 .proc_handler   = &proc_dointvec,
 306         },
 307         {
 308                 .ctl_name       = KERN_CAP_BSET,
 309                 .procname       = "cap-bound",
 310                 .data           = &cap_bset,
 311                 .maxlen         = sizeof(kernel_cap_t),
 312                 .mode           = 0600,
 313                 .proc_handler   = &proc_dointvec_bset,
 314         },
 315 #ifdef CONFIG_BLK_DEV_INITRD
 316         {
 317                 .ctl_name       = KERN_REALROOTDEV,
 318                 .procname       = "real-root-dev",
 319                 .data           = &real_root_dev,
 320                 .maxlen         = sizeof(int),
 321                 .mode           = 0644,
 322                 .proc_handler   = &proc_dointvec,
 323         },
 324 #endif
 325 #ifdef __sparc__
 326         {
 327                 .ctl_name       = KERN_SPARC_REBOOT,
 328                 .procname       = "reboot-cmd",
 329                 .data           = reboot_command,
 330                 .maxlen         = 256,
 331                 .mode           = 0644,
 332                 .proc_handler   = &proc_dostring,
 333                 .strategy       = &sysctl_string,
 334         },
 335         {
 336                 .ctl_name       = KERN_SPARC_STOP_A,
 337                 .procname       = "stop-a",
 338                 .data           = &stop_a_enabled,
 339                 .maxlen         = sizeof (int),
 340                 .mode           = 0644,
 341                 .proc_handler   = &proc_dointvec,
 342         },
 343         {
 344                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 345                 .procname       = "scons-poweroff",
 346                 .data           = &scons_pwroff,
 347                 .maxlen         = sizeof (int),
 348                 .mode           = 0644,
 349                 .proc_handler   = &proc_dointvec,
 350         },
 351 #endif
 352 #ifdef __hppa__
 353         {
 354                 .ctl_name       = KERN_HPPA_PWRSW,
 355                 .procname       = "soft-power",
 356                 .data           = &pwrsw_enabled,
 357                 .maxlen         = sizeof (int),
 358                 .mode           = 0644,
 359                 .proc_handler   = &proc_dointvec,
 360         },
 361         {
 362                 .ctl_name       = KERN_HPPA_UNALIGNED,
 363                 .procname       = "unaligned-trap",
 364                 .data           = &unaligned_enabled,
 365                 .maxlen         = sizeof (int),
 366                 .mode           = 0644,
 367                 .proc_handler   = &proc_dointvec,
 368         },
 369 #endif
 370         {
 371                 .ctl_name       = KERN_CTLALTDEL,
 372                 .procname       = "ctrl-alt-del",
 373                 .data           = &C_A_D,
 374                 .maxlen         = sizeof(int),
 375                 .mode           = 0644,
 376                 .proc_handler   = &proc_dointvec,
 377         },
 378         {
 379                 .ctl_name       = KERN_PRINTK,
 380                 .procname       = "printk",
 381                 .data           = &console_loglevel,
 382                 .maxlen         = 4*sizeof(int),
 383                 .mode           = 0644,
 384                 .proc_handler   = &proc_dointvec,
 385         },
 386 #ifdef CONFIG_KMOD
 387         {
 388                 .ctl_name       = KERN_MODPROBE,
 389                 .procname       = "modprobe",
 390                 .data           = &modprobe_path,
 391                 .maxlen         = KMOD_PATH_LEN,
 392                 .mode           = 0644,
 393                 .proc_handler   = &proc_dostring,
 394                 .strategy       = &sysctl_string,
 395         },
 396 #endif
 397 #ifdef CONFIG_HOTPLUG
 398         {
 399                 .ctl_name       = KERN_HOTPLUG,
 400                 .procname       = "hotplug",
 401                 .data           = &hotplug_path,
 402                 .maxlen         = HOTPLUG_PATH_LEN,
 403                 .mode           = 0644,
 404                 .proc_handler   = &proc_dostring,
 405                 .strategy       = &sysctl_string,
 406         },
 407 #endif
 408 #ifdef CONFIG_CHR_DEV_SG
 409         {
 410                 .ctl_name       = KERN_SG_BIG_BUFF,
 411                 .procname       = "sg-big-buff",
 412                 .data           = &sg_big_buff,
 413                 .maxlen         = sizeof (int),
 414                 .mode           = 0444,
 415                 .proc_handler   = &proc_dointvec,
 416         },
 417 #endif
 418 #ifdef CONFIG_BSD_PROCESS_ACCT
 419         {
 420                 .ctl_name       = KERN_ACCT,
 421                 .procname       = "acct",
 422                 .data           = &acct_parm,
 423                 .maxlen         = 3*sizeof(int),
 424                 .mode           = 0644,
 425                 .proc_handler   = &proc_dointvec,
 426         },
 427 #endif
 428 #ifdef CONFIG_SYSVIPC
 429         {
 430                 .ctl_name       = KERN_SHMMAX,
 431                 .procname       = "shmmax",
 432                 .data           = &shm_ctlmax,
 433                 .maxlen         = sizeof (size_t),
 434                 .mode           = 0644,
 435                 .proc_handler   = &proc_doulongvec_minmax,
 436         },
 437         {
 438                 .ctl_name       = KERN_SHMALL,
 439                 .procname       = "shmall",
 440                 .data           = &shm_ctlall,
 441                 .maxlen         = sizeof (size_t),
 442                 .mode           = 0644,
 443                 .proc_handler   = &proc_doulongvec_minmax,
 444         },
 445         {
 446                 .ctl_name       = KERN_SHMMNI,
 447                 .procname       = "shmmni",
 448                 .data           = &shm_ctlmni,
 449                 .maxlen         = sizeof (int),
 450                 .mode           = 0644,
 451                 .proc_handler   = &proc_dointvec,
 452         },
 453         {
 454                 .ctl_name       = KERN_MSGMAX,
 455                 .procname       = "msgmax",
 456                 .data           = &msg_ctlmax,
 457                 .maxlen         = sizeof (int),
 458                 .mode           = 0644,
 459                 .proc_handler   = &proc_dointvec,
 460         },
 461         {
 462                 .ctl_name       = KERN_MSGMNI,
 463                 .procname       = "msgmni",
 464                 .data           = &msg_ctlmni,
 465                 .maxlen         = sizeof (int),
 466                 .mode           = 0644,
 467                 .proc_handler   = &proc_dointvec,
 468         },
 469         {
 470                 .ctl_name       = KERN_MSGMNB,
 471                 .procname       =  "msgmnb",
 472                 .data           = &msg_ctlmnb,
 473                 .maxlen         = sizeof (int),
 474                 .mode           = 0644,
 475                 .proc_handler   = &proc_dointvec,
 476         },
 477         {
 478                 .ctl_name       = KERN_SEM,
 479                 .procname       = "sem",
 480                 .data           = &sem_ctls,
 481                 .maxlen         = 4*sizeof (int),
 482                 .mode           = 0644,
 483                 .proc_handler   = &proc_dointvec,
 484         },
 485 #endif
 486 #ifdef CONFIG_MAGIC_SYSRQ
 487         {
 488                 .ctl_name       = KERN_SYSRQ,
 489                 .procname       = "sysrq",
 490                 .data           = &sysrq_enabled,
 491                 .maxlen         = sizeof (int),
 492                 .mode           = 0644,
 493                 .proc_handler   = &proc_dointvec,
 494         },
 495 #endif
 496         {
 497                 .ctl_name       = KERN_CADPID,
 498                 .procname       = "cad_pid",
 499                 .data           = &cad_pid,
 500                 .maxlen         = sizeof (int),
 501                 .mode           = 0600,
 502                 .proc_handler   = &proc_dointvec,
 503         },
 504         {
 505                 .ctl_name       = KERN_MAX_THREADS,
 506                 .procname       = "threads-max",
 507                 .data           = &max_threads,
 508                 .maxlen         = sizeof(int),
 509                 .mode           = 0644,
 510                 .proc_handler   = &proc_dointvec,
 511         },
 512         {
 513                 .ctl_name       = KERN_RANDOM,
 514                 .procname       = "random",
 515                 .mode           = 0555,
 516                 .child          = random_table,
 517         },
 518 #ifdef CONFIG_UNIX98_PTYS
 519         {
 520                 .ctl_name       = KERN_PTY,
 521                 .procname       = "pty",
 522                 .mode           = 0555,
 523                 .child          = pty_table,
 524         },
 525 #endif
 526         {
 527                 .ctl_name       = KERN_OVERFLOWUID,
 528                 .procname       = "overflowuid",
 529                 .data           = &overflowuid,
 530                 .maxlen         = sizeof(int),
 531                 .mode           = 0644,
 532                 .proc_handler   = &proc_dointvec_minmax,
 533                 .strategy       = &sysctl_intvec,
 534                 .extra1         = &minolduid,
 535                 .extra2         = &maxolduid,
 536         },
 537         {
 538                 .ctl_name       = KERN_OVERFLOWGID,
 539                 .procname       = "overflowgid",
 540                 .data           = &overflowgid,
 541                 .maxlen         = sizeof(int),
 542                 .mode           = 0644,
 543                 .proc_handler   = &proc_dointvec_minmax,
 544                 .strategy       = &sysctl_intvec,
 545                 .extra1         = &minolduid,
 546                 .extra2         = &maxolduid,
 547         },
 548 #ifdef CONFIG_ARCH_S390
 549 #ifdef CONFIG_MATHEMU
 550         {
 551                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 552                 .procname       = "ieee_emulation_warnings",
 553                 .data           = &sysctl_ieee_emulation_warnings,
 554                 .maxlen         = sizeof(int),
 555                 .mode           = 0644,
 556                 .proc_handler   = &proc_dointvec,
 557         },
 558 #endif
 559 #ifdef CONFIG_NO_IDLE_HZ
 560         {
 561                 .ctl_name       = KERN_HZ_TIMER,
 562                 .procname       = "hz_timer",
 563                 .data           = &sysctl_hz_timer,
 564                 .maxlen         = sizeof(int),
 565                 .mode           = 0644,
 566                 .proc_handler   = &proc_dointvec,
 567         },
 568 #endif
 569         {
 570                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 571                 .procname       = "userprocess_debug",
 572                 .data           = &sysctl_userprocess_debug,
 573                 .maxlen         = sizeof(int),
 574                 .mode           = 0644,
 575                 .proc_handler   = &proc_dointvec,
 576         },
 577 #endif
 578         {
 579                 .ctl_name       = KERN_PIDMAX,
 580                 .procname       = "pid_max",
 581                 .data           = &pid_max,
 582                 .maxlen         = sizeof (int),
 583                 .mode           = 0644,
 584                 .proc_handler   = &proc_dointvec_minmax,
 585                 .strategy       = sysctl_intvec,
 586                 .extra1         = &pid_max_min,
 587                 .extra2         = &pid_max_max,
 588         },
 589         {
 590                 .ctl_name       = KERN_PANIC_ON_OOPS,
 591                 .procname       = "panic_on_oops",
 592                 .data           = &panic_on_oops,
 593                 .maxlen         = sizeof(int),
 594                 .mode           = 0644,
 595                 .proc_handler   = &proc_dointvec,
 596         },
 597         {
 598                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 599                 .procname       = "printk_ratelimit",
 600                 .data           = &printk_ratelimit_jiffies,
 601                 .maxlen         = sizeof(int),
 602                 .mode           = 0644,
 603                 .proc_handler   = &proc_dointvec_jiffies,
 604                 .strategy       = &sysctl_jiffies,
 605         },
 606         {
 607                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 608                 .procname       = "printk_ratelimit_burst",
 609                 .data           = &printk_ratelimit_burst,
 610                 .maxlen         = sizeof(int),
 611                 .mode           = 0644,
 612                 .proc_handler   = &proc_dointvec,
 613         },
 614         {
 615                 .ctl_name       = KERN_NGROUPS_MAX,
 616                 .procname       = "ngroups_max",
 617                 .data           = &ngroups_max,
 618                 .maxlen         = sizeof (int),
 619                 .mode           = 0444,
 620                 .proc_handler   = &proc_dointvec,
 621         },
 622 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 623         {
 624                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
 625                 .procname       = "unknown_nmi_panic",
 626                 .data           = &unknown_nmi_panic,
 627                 .maxlen         = sizeof (int),
 628                 .mode           = 0644,
 629                 .proc_handler   = &proc_unknown_nmi_panic,
 630         },
 631 #endif
 632 #if defined(CONFIG_X86)
 633         {
 634                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 635                 .procname       = "bootloader_type",
 636                 .data           = &bootloader_type,
 637                 .maxlen         = sizeof (int),
 638                 .mode           = 0444,
 639                 .proc_handler   = &proc_dointvec,
 640         },
 641 #endif
 642         {
 643                 .ctl_name       = KERN_RANDOMIZE,
 644                 .procname       = "randomize_va_space",
 645                 .data           = &randomize_va_space,
 646                 .maxlen         = sizeof(int),
 647                 .mode           = 0644,
 648                 .proc_handler   = &proc_dointvec,
 649         },
 650
 651         { .ctl_name = 0 }
 652 };
 653
 654 /* Constants for minimum and maximum testing in vm_table.
 655    We use these as one-element integer vectors. */
 656 static int zero;
 657 static int one_hundred = 100;
 658
 659
 660 static ctl_table vm_table[] = {
 661         {
 662                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
 663                 .procname       = "overcommit_memory",
 664                 .data           = &sysctl_overcommit_memory,
 665                 .maxlen         = sizeof(sysctl_overcommit_memory),
 666                 .mode           = 0644,
 667                 .proc_handler   = &proc_dointvec,
 668         },
 669         {
 670                 .ctl_name       = VM_OVERCOMMIT_RATIO,
 671                 .procname       = "overcommit_ratio",
 672                 .data           = &sysctl_overcommit_ratio,
 673                 .maxlen         = sizeof(sysctl_overcommit_ratio),
 674                 .mode           = 0644,
 675                 .proc_handler   = &proc_dointvec,
 676         },
 677         {
 678                 .ctl_name       = VM_PAGE_CLUSTER,
 679                 .procname       = "page-cluster",
 680                 .data           = &page_cluster,
 681                 .maxlen         = sizeof(int),
 682                 .mode           = 0644,
 683                 .proc_handler   = &proc_dointvec,
 684         },
 685         {
 686                 .ctl_name       = VM_DIRTY_BACKGROUND,
 687                 .procname       = "dirty_background_ratio",
 688                 .data           = &dirty_background_ratio,
 689                 .maxlen         = sizeof(dirty_background_ratio),
 690                 .mode           = 0644,
 691                 .proc_handler   = &proc_dointvec_minmax,
 692                 .strategy       = &sysctl_intvec,
 693                 .extra1         = &zero,
 694                 .extra2         = &one_hundred,
 695         },
 696         {
 697                 .ctl_name       = VM_DIRTY_RATIO,
 698                 .procname       = "dirty_ratio",
 699                 .data           = &vm_dirty_ratio,
 700                 .maxlen         = sizeof(vm_dirty_ratio),
 701                 .mode           = 0644,
 702                 .proc_handler   = &proc_dointvec_minmax,
 703                 .strategy       = &sysctl_intvec,
 704                 .extra1         = &zero,
 705                 .extra2         = &one_hundred,
 706         },
 707         {
 708                 .ctl_name       = VM_DIRTY_WB_CS,
 709                 .procname       = "dirty_writeback_centisecs",
 710                 .data           = &dirty_writeback_centisecs,
 711                 .maxlen         = sizeof(dirty_writeback_centisecs),
 712                 .mode           = 0644,
 713                 .proc_handler   = &dirty_writeback_centisecs_handler,
 714         },
 715         {
 716                 .ctl_name       = VM_DIRTY_EXPIRE_CS,
 717                 .procname       = "dirty_expire_centisecs",
 718                 .data           = &dirty_expire_centisecs,
 719                 .maxlen         = sizeof(dirty_expire_centisecs),
 720                 .mode           = 0644,
 721                 .proc_handler   = &proc_dointvec,
 722         },
 723         {
 724                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
 725                 .procname       = "nr_pdflush_threads",
 726                 .data           = &nr_pdflush_threads,
 727                 .maxlen         = sizeof nr_pdflush_threads,
 728                 .mode           = 0444 /* read-only*/,
 729                 .proc_handler   = &proc_dointvec,
 730         },
 731         {
 732                 .ctl_name       = VM_SWAPPINESS,
 733                 .procname       = "swappiness",
 734                 .data           = &vm_swappiness,
 735                 .maxlen         = sizeof(vm_swappiness),
 736                 .mode           = 0644,
 737                 .proc_handler   = &proc_dointvec_minmax,
 738                 .strategy       = &sysctl_intvec,
 739                 .extra1         = &zero,
 740                 .extra2         = &one_hundred,
 741         },
 742 #ifdef CONFIG_HUGETLB_PAGE
 743          {
 744                 .ctl_name       = VM_HUGETLB_PAGES,
 745                 .procname       = "nr_hugepages",
 746                 .data           = &max_huge_pages,
 747                 .maxlen         = sizeof(unsigned long),
 748                 .mode           = 0644,
 749                 .proc_handler   = &hugetlb_sysctl_handler,
 750                 .extra1         = (void *)&hugetlb_zero,
 751                 .extra2         = (void *)&hugetlb_infinity,
 752          },
 753          {
 754                 .ctl_name       = VM_HUGETLB_GROUP,
 755                 .procname       = "hugetlb_shm_group",
 756                 .data           = &sysctl_hugetlb_shm_group,
 757                 .maxlen         = sizeof(gid_t),
 758                 .mode           = 0644,
 759                 .proc_handler   = &proc_dointvec,
 760          },
 761 #endif
 762         {
 763                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
 764                 .procname       = "lowmem_reserve_ratio",
 765                 .data           = &sysctl_lowmem_reserve_ratio,
 766                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
 767                 .mode           = 0644,
 768                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
 769                 .strategy       = &sysctl_intvec,
 770         },
 771         {
 772                 .ctl_name       = VM_MIN_FREE_KBYTES,
 773                 .procname       = "min_free_kbytes",
 774                 .data           = &min_free_kbytes,
 775                 .maxlen         = sizeof(min_free_kbytes),
 776                 .mode           = 0644,
 777                 .proc_handler   = &min_free_kbytes_sysctl_handler,
 778                 .strategy       = &sysctl_intvec,
 779                 .extra1         = &zero,
 780         },
 781 #ifdef CONFIG_MMU
 782         {
 783                 .ctl_name       = VM_MAX_MAP_COUNT,
 784                 .procname       = "max_map_count",
 785                 .data           = &sysctl_max_map_count,
 786                 .maxlen         = sizeof(sysctl_max_map_count),
 787                 .mode           = 0644,
 788                 .proc_handler   = &proc_dointvec
 789         },
 790 #endif
 791         {
 792                 .ctl_name       = VM_LAPTOP_MODE,
 793                 .procname       = "laptop_mode",
 794                 .data           = &laptop_mode,
 795                 .maxlen         = sizeof(laptop_mode),
 796                 .mode           = 0644,
 797                 .proc_handler   = &proc_dointvec,
 798                 .strategy       = &sysctl_intvec,
 799                 .extra1         = &zero,
 800         },
 801         {
 802                 .ctl_name       = VM_BLOCK_DUMP,
 803                 .procname       = "block_dump",
 804                 .data           = &block_dump,
 805                 .maxlen         = sizeof(block_dump),
 806                 .mode           = 0644,
 807                 .proc_handler   = &proc_dointvec,
 808                 .strategy       = &sysctl_intvec,
 809                 .extra1         = &zero,
 810         },
 811         {
 812                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
 813                 .procname       = "vfs_cache_pressure",
 814                 .data           = &sysctl_vfs_cache_pressure,
 815                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
 816                 .mode           = 0644,
 817                 .proc_handler   = &proc_dointvec,
 818                 .strategy       = &sysctl_intvec,
 819                 .extra1         = &zero,
 820         },
 821 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 822         {
 823                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
 824                 .procname       = "legacy_va_layout",
 825                 .data           = &sysctl_legacy_va_layout,
 826                 .maxlen         = sizeof(sysctl_legacy_va_layout),
 827                 .mode           = 0644,
 828                 .proc_handler   = &proc_dointvec,
 829                 .strategy       = &sysctl_intvec,
 830                 .extra1         = &zero,
 831         },
 832 #endif
 833 #ifdef CONFIG_SWAP
 834         {
 835                 .ctl_name       = VM_SWAP_TOKEN_TIMEOUT,
 836                 .procname       = "swap_token_timeout",
 837                 .data           = &swap_token_default_timeout,
 838                 .maxlen         = sizeof(swap_token_default_timeout),
 839                 .mode           = 0644,
 840                 .proc_handler   = &proc_dointvec_jiffies,
 841                 .strategy       = &sysctl_jiffies,
 842         },
 843 #endif
 844         { .ctl_name = 0 }
 845 };
 846
 847 static ctl_table proc_table[] = {
 848         { .ctl_name = 0 }
 849 };
 850
 851 static ctl_table fs_table[] = {
 852         {
 853                 .ctl_name       = FS_NRINODE,
 854                 .procname       = "inode-nr",
 855                 .data           = &inodes_stat,
 856                 .maxlen         = 2*sizeof(int),
 857                 .mode           = 0444,
 858                 .proc_handler   = &proc_dointvec,
 859         },
 860         {
 861                 .ctl_name       = FS_STATINODE,
 862                 .procname       = "inode-state",
 863                 .data           = &inodes_stat,
 864                 .maxlen         = 7*sizeof(int),
 865                 .mode           = 0444,
 866                 .proc_handler   = &proc_dointvec,
 867         },
 868         {
 869                 .ctl_name       = FS_NRFILE,
 870                 .procname       = "file-nr",
 871                 .data           = &files_stat,
 872                 .maxlen         = 3*sizeof(int),
 873                 .mode           = 0444,
 874                 .proc_handler   = &proc_dointvec,
 875         },
 876         {
 877                 .ctl_name       = FS_MAXFILE,
 878                 .procname       = "file-max",
 879                 .data           = &files_stat.max_files,
 880                 .maxlen         = sizeof(int),
 881                 .mode           = 0644,
 882                 .proc_handler   = &proc_dointvec,
 883         },
 884         {
 885                 .ctl_name       = FS_DENTRY,
 886                 .procname       = "dentry-state",
 887                 .data           = &dentry_stat,
 888                 .maxlen         = 6*sizeof(int),
 889                 .mode           = 0444,
 890                 .proc_handler   = &proc_dointvec,
 891         },
 892         {
 893                 .ctl_name       = FS_OVERFLOWUID,
 894                 .procname       = "overflowuid",
 895                 .data           = &fs_overflowuid,
 896                 .maxlen         = sizeof(int),
 897                 .mode           = 0644,
 898                 .proc_handler   = &proc_dointvec_minmax,
 899                 .strategy       = &sysctl_intvec,
 900                 .extra1         = &minolduid,
 901                 .extra2         = &maxolduid,
 902         },
 903         {
 904                 .ctl_name       = FS_OVERFLOWGID,
 905                 .procname       = "overflowgid",
 906                 .data           = &fs_overflowgid,
 907                 .maxlen         = sizeof(int),
 908                 .mode           = 0644,
 909                 .proc_handler   = &proc_dointvec_minmax,
 910                 .strategy       = &sysctl_intvec,
 911                 .extra1         = &minolduid,
 912                 .extra2         = &maxolduid,
 913         },
 914         {
 915                 .ctl_name       = FS_LEASES,
 916                 .procname       = "leases-enable",
 917                 .data           = &leases_enable,
 918                 .maxlen         = sizeof(int),
 919                 .mode           = 0644,
 920                 .proc_handler   = &proc_dointvec,
 921         },
 922 #ifdef CONFIG_DNOTIFY
 923         {
 924                 .ctl_name       = FS_DIR_NOTIFY,
 925                 .procname       = "dir-notify-enable",
 926                 .data           = &dir_notify_enable,
 927                 .maxlen         = sizeof(int),
 928                 .mode           = 0644,
 929                 .proc_handler   = &proc_dointvec,
 930         },
 931 #endif
 932 #ifdef CONFIG_MMU
 933         {
 934                 .ctl_name       = FS_LEASE_TIME,
 935                 .procname       = "lease-break-time",
 936                 .data           = &lease_break_time,
 937                 .maxlen         = sizeof(int),
 938                 .mode           = 0644,
 939                 .proc_handler   = &proc_dointvec,
 940         },
 941         {
 942                 .ctl_name       = FS_AIO_NR,
 943                 .procname       = "aio-nr",
 944                 .data           = &aio_nr,
 945                 .maxlen         = sizeof(aio_nr),
 946                 .mode           = 0444,
 947                 .proc_handler   = &proc_dointvec,
 948         },
 949         {
 950                 .ctl_name       = FS_AIO_MAX_NR,
 951                 .procname       = "aio-max-nr",
 952                 .data           = &aio_max_nr,
 953                 .maxlen         = sizeof(aio_max_nr),
 954                 .mode           = 0644,
 955                 .proc_handler   = &proc_dointvec,
 956         },
 957 #ifdef CONFIG_INOTIFY
 958         {
 959                 .ctl_name       = FS_INOTIFY,
 960                 .procname       = "inotify",
 961                 .mode           = 0555,
 962                 .child          = inotify_table,
 963         },
 964 #endif
 965 #endif
 966         {
 967                 .ctl_name       = KERN_SETUID_DUMPABLE,
 968                 .procname       = "suid_dumpable",
 969                 .data           = &suid_dumpable,
 970                 .maxlen         = sizeof(int),
 971                 .mode           = 0644,
 972                 .proc_handler   = &proc_dointvec,
 973         },
 974         { .ctl_name = 0 }
 975 };
 976
 977 static ctl_table debug_table[] = {
 978         { .ctl_name = 0 }
 979 };
 980
 981 static ctl_table dev_table[] = {
 982         { .ctl_name = 0 }
 983 };
 984
 985 extern void init_irq_proc (void);
 986
 987 void __init sysctl_init(void)
 988 {
 989 #ifdef CONFIG_PROC_FS
 990         register_proc_table(root_table, proc_sys_root);
 991         init_irq_proc();
 992 #endif
 993 }
 994
 995 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
 996                void __user *newval, size_t newlen)
 997 {
 998         struct list_head *tmp;
 999
1000         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1001                 return -ENOTDIR;
1002         if (oldval) {
1003                 int old_len;
1004                 if (!oldlenp || get_user(old_len, oldlenp))
1005                         return -EFAULT;
1006         }
1007         tmp = &root_table_header.ctl_entry;
1008         do {
1009                 struct ctl_table_header *head =
1010                         list_entry(tmp, struct ctl_table_header, ctl_entry);
1011                 void *context = NULL;
1012                 int error = parse_table(name, nlen, oldval, oldlenp,
1013                                         newval, newlen, head->ctl_table,
1014                                         &context);
1015                 kfree(context);
1016                 if (error != -ENOTDIR)
1017                         return error;
1018                 tmp = tmp->next;
1019         } while (tmp != &root_table_header.ctl_entry);
1020         return -ENOTDIR;
1021 }
1022
1023 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1024 {
1025         struct __sysctl_args tmp;
1026         int error;
1027
1028         if (copy_from_user(&tmp, args, sizeof(tmp)))
1029                 return -EFAULT;
1030
1031         lock_kernel();
1032         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1033                           tmp.newval, tmp.newlen);
1034         unlock_kernel();
1035         return error;
1036 }
1037
1038 /*
1039  * ctl_perm does NOT grant the superuser all rights automatically, because
1040  * some sysctl variables are readonly even to root.
1041  */
1042
1043 static int test_perm(int mode, int op)
1044 {
1045         if (!current->euid)
1046                 mode >>= 6;
1047         else if (in_egroup_p(0))
1048                 mode >>= 3;
1049         if ((mode & op & 0007) == op)
1050                 return 0;
1051         return -EACCES;
1052 }
1053
1054 static inline int ctl_perm(ctl_table *table, int op)
1055 {
1056         int error;
1057         error = security_sysctl(table, op);
1058         if (error)
1059                 return error;
1060         return test_perm(table->mode, op);
1061 }
1062
1063 static int parse_table(int __user *name, int nlen,
1064                        void __user *oldval, size_t __user *oldlenp,
1065                        void __user *newval, size_t newlen,
1066                        ctl_table *table, void **context)
1067 {
1068         int n;
1069 repeat:
1070         if (!nlen)
1071                 return -ENOTDIR;
1072         if (get_user(n, name))
1073                 return -EFAULT;
1074         for ( ; table->ctl_name; table++) {
1075                 if (n == table->ctl_name || table->ctl_name == CTL_ANY) {
1076                         int error;
1077                         if (table->child) {
1078                                 if (ctl_perm(table, 001))
1079                                         return -EPERM;
1080                                 if (table->strategy) {
1081                                         error = table->strategy(
1082                                                 table, name, nlen,
1083                                                 oldval, oldlenp,
1084                                                 newval, newlen, context);
1085                                         if (error)
1086                                                 return error;
1087                                 }
1088                                 name++;
1089                                 nlen--;
1090                                 table = table->child;
1091                                 goto repeat;
1092                         }
1093                         error = do_sysctl_strategy(table, name, nlen,
1094                                                    oldval, oldlenp,
1095                                                    newval, newlen, context);
1096                         return error;
1097                 }
1098         }
1099         return -ENOTDIR;
1100 }
1101
1102 /* Perform the actual read/write of a sysctl table entry. */
1103 int do_sysctl_strategy (ctl_table *table,
1104                         int __user *name, int nlen,
1105                         void __user *oldval, size_t __user *oldlenp,
1106                         void __user *newval, size_t newlen, void **context)
1107 {
1108         int op = 0, rc;
1109         size_t len;
1110
1111         if (oldval)
1112                 op |= 004;
1113         if (newval)
1114                 op |= 002;
1115         if (ctl_perm(table, op))
1116                 return -EPERM;
1117
1118         if (table->strategy) {
1119                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1120                                      newval, newlen, context);
1121                 if (rc < 0)
1122                         return rc;
1123                 if (rc > 0)
1124                         return 0;
1125         }
1126
1127         /* If there is no strategy routine, or if the strategy returns
1128          * zero, proceed with automatic r/w */
1129         if (table->data && table->maxlen) {
1130                 if (oldval && oldlenp) {
1131                         if (get_user(len, oldlenp))
1132                                 return -EFAULT;
1133                         if (len) {
1134                                 if (len > table->maxlen)
1135                                         len = table->maxlen;
1136                                 if(copy_to_user(oldval, table->data, len))
1137                                         return -EFAULT;
1138                                 if(put_user(len, oldlenp))
1139                                         return -EFAULT;
1140                         }
1141                 }
1142                 if (newval && newlen) {
1143                         len = newlen;
1144                         if (len > table->maxlen)
1145                                 len = table->maxlen;
1146                         if(copy_from_user(table->data, newval, len))
1147                                 return -EFAULT;
1148                 }
1149         }
1150         return 0;
1151 }
1152
1153 /**
1154  * register_sysctl_table - register a sysctl hierarchy
1155  * @table: the top-level table structure
1156  * @insert_at_head: whether the entry should be inserted in front or at the end
1157  *
1158  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1159  * array. An entry with a ctl_name of 0 terminates the table.
1160  *
1161  * The members of the &ctl_table structure are used as follows:
1162  *
1163  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1164  *            must be unique within that level of sysctl
1165  *
1166  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1167  *            enter a sysctl file
1168  *
1169  * data - a pointer to data for use by proc_handler
1170  *
1171  * maxlen - the maximum size in bytes of the data
1172  *
1173  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1174  *
1175  * child - a pointer to the child sysctl table if this entry is a directory, or
1176  *         %NULL.
1177  *
1178  * proc_handler - the text handler routine (described below)
1179  *
1180  * strategy - the strategy routine (described below)
1181  *
1182  * de - for internal use by the sysctl routines
1183  *
1184  * extra1, extra2 - extra pointers usable by the proc handler routines
1185  *
1186  * Leaf nodes in the sysctl tree will be represented by a single file
1187  * under /proc; non-leaf nodes will be represented by directories.
1188  *
1189  * sysctl(2) can automatically manage read and write requests through
1190  * the sysctl table.  The data and maxlen fields of the ctl_table
1191  * struct enable minimal validation of the values being written to be
1192  * performed, and the mode field allows minimal authentication.
1193  *
1194  * More sophisticated management can be enabled by the provision of a
1195  * strategy routine with the table entry.  This will be called before
1196  * any automatic read or write of the data is performed.
1197  *
1198  * The strategy routine may return
1199  *
1200  * < 0 - Error occurred (error is passed to user process)
1201  *
1202  * 0   - OK - proceed with automatic read or write.
1203  *
1204  * > 0 - OK - read or write has been done by the strategy routine, so
1205  *       return immediately.
1206  *
1207  * There must be a proc_handler routine for any terminal nodes
1208  * mirrored under /proc/sys (non-terminals are handled by a built-in
1209  * directory handler).  Several default handlers are available to
1210  * cover common cases -
1211  *
1212  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1213  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1214  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1215  *
1216  * It is the handler's job to read the input buffer from user memory
1217  * and process it. The handler should return 0 on success.
1218  *
1219  * This routine returns %NULL on a failure to register, and a pointer
1220  * to the table header on success.
1221  */
1222 struct ctl_table_header *register_sysctl_table(ctl_table * table,
1223                                                int insert_at_head)
1224 {
1225         struct ctl_table_header *tmp;
1226         tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1227         if (!tmp)
1228                 return NULL;
1229         tmp->ctl_table = table;
1230         INIT_LIST_HEAD(&tmp->ctl_entry);
1231         if (insert_at_head)
1232                 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
1233         else
1234                 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1235 #ifdef CONFIG_PROC_FS
1236         register_proc_table(table, proc_sys_root);
1237 #endif
1238         return tmp;
1239 }
1240
1241 /**
1242  * unregister_sysctl_table - unregister a sysctl table hierarchy
1243  * @header: the header returned from register_sysctl_table
1244  *
1245  * Unregisters the sysctl table and all children. proc entries may not
1246  * actually be removed until they are no longer used by anyone.
1247  */
1248 void unregister_sysctl_table(struct ctl_table_header * header)
1249 {
1250         list_del(&header->ctl_entry);
1251 #ifdef CONFIG_PROC_FS
1252         unregister_proc_table(header->ctl_table, proc_sys_root);
1253 #endif
1254         kfree(header);
1255 }
1256
1257 /*
1258  * /proc/sys support
1259  */
1260
1261 #ifdef CONFIG_PROC_FS
1262
1263 /* Scan the sysctl entries in table and add them all into /proc */
1264 static void register_proc_table(ctl_table * table, struct proc_dir_entry *root)
1265 {
1266         struct proc_dir_entry *de;
1267         int len;
1268         mode_t mode;
1269
1270         for (; table->ctl_name; table++) {
1271                 /* Can't do anything without a proc name. */
1272                 if (!table->procname)
1273                         continue;
1274                 /* Maybe we can't do anything with it... */
1275                 if (!table->proc_handler && !table->child) {
1276                         printk(KERN_WARNING "SYSCTL: Can't register %s\n",
1277                                 table->procname);
1278                         continue;
1279                 }
1280
1281                 len = strlen(table->procname);
1282                 mode = table->mode;
1283
1284                 de = NULL;
1285                 if (table->proc_handler)
1286                         mode |= S_IFREG;
1287                 else {
1288                         mode |= S_IFDIR;
1289                         for (de = root->subdir; de; de = de->next) {
1290                                 if (proc_match(len, table->procname, de))
1291                                         break;
1292                         }
1293                         /* If the subdir exists already, de is non-NULL */
1294                 }
1295
1296                 if (!de) {
1297                         de = create_proc_entry(table->procname, mode, root);
1298                         if (!de)
1299                                 continue;
1300                         de->data = (void *) table;
1301                         if (table->proc_handler)
1302                                 de->proc_fops = &proc_sys_file_operations;
1303                 }
1304                 table->de = de;
1305                 if (de->mode & S_IFDIR)
1306                         register_proc_table(table->child, de);
1307         }
1308 }
1309
1310 /*
1311  * Unregister a /proc sysctl table and any subdirectories.
1312  */
1313 static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
1314 {
1315         struct proc_dir_entry *de;
1316         for (; table->ctl_name; table++) {
1317                 if (!(de = table->de))
1318                         continue;
1319                 if (de->mode & S_IFDIR) {
1320                         if (!table->child) {
1321                                 printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
1322                                 continue;
1323                         }
1324                         unregister_proc_table(table->child, de);
1325
1326                         /* Don't unregister directories which still have entries.. */
1327                         if (de->subdir)
1328                                 continue;
1329                 }
1330
1331                 /* Don't unregister proc entries that are still being used.. */
1332                 if (atomic_read(&de->count))
1333                         continue;
1334
1335                 table->de = NULL;
1336                 remove_proc_entry(table->procname, root);
1337         }
1338 }
1339
1340 static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
1341                           size_t count, loff_t *ppos)
1342 {
1343         int op;
1344         struct proc_dir_entry *de;
1345         struct ctl_table *table;
1346         size_t res;
1347         ssize_t error;
1348
1349         de = PDE(file->f_dentry->d_inode);
1350         if (!de || !de->data)
1351                 return -ENOTDIR;
1352         table = (struct ctl_table *) de->data;
1353         if (!table || !table->proc_handler)
1354                 return -ENOTDIR;
1355         op = (write ? 002 : 004);
1356         if (ctl_perm(table, op))
1357                 return -EPERM;
1358
1359         res = count;
1360
1361         error = (*table->proc_handler) (table, write, file, buf, &res, ppos);
1362         if (error)
1363                 return error;
1364         return res;
1365 }
1366
1367 static int proc_opensys(struct inode *inode, struct file *file)
1368 {
1369         if (file->f_mode & FMODE_WRITE) {
1370                 /*
1371                  * sysctl entries that are not writable,
1372                  * are _NOT_ writable, capabilities or not.
1373                  */
1374                 if (!(inode->i_mode & S_IWUSR))
1375                         return -EPERM;
1376         }
1377
1378         return 0;
1379 }
1380
1381 static ssize_t proc_readsys(struct file * file, char __user * buf,
1382                             size_t count, loff_t *ppos)
1383 {
1384         return do_rw_proc(0, file, buf, count, ppos);
1385 }
1386
1387 static ssize_t proc_writesys(struct file * file, const char __user * buf,
1388                              size_t count, loff_t *ppos)
1389 {
1390         return do_rw_proc(1, file, (char __user *) buf, count, ppos);
1391 }
1392
1393 /**
1394  * proc_dostring - read a string sysctl
1395  * @table: the sysctl table
1396  * @write: %TRUE if this is a write to the sysctl file
1397  * @filp: the file structure
1398  * @buffer: the user buffer
1399  * @lenp: the size of the user buffer
1400  * @ppos: file position
1401  *
1402  * Reads/writes a string from/to the user buffer. If the kernel
1403  * buffer provided is not large enough to hold the string, the
1404  * string is truncated. The copied string is %NULL-terminated.
1405  * If the string is being read by the user process, it is copied
1406  * and a newline '\n' is added. It is truncated if the buffer is
1407  * not large enough.
1408  *
1409  * Returns 0 on success.
1410  */
1411 int proc_dostring(ctl_table *table, int write, struct file *filp,
1412                   void __user *buffer, size_t *lenp, loff_t *ppos)
1413 {
1414         size_t len;
1415         char __user *p;
1416         char c;
1417
1418         if (!table->data || !table->maxlen || !*lenp ||
1419             (*ppos && !write)) {
1420                 *lenp = 0;
1421                 return 0;
1422         }
1423
1424         if (write) {
1425                 len = 0;
1426                 p = buffer;
1427                 while (len < *lenp) {
1428                         if (get_user(c, p++))
1429                                 return -EFAULT;
1430                         if (c == 0 || c == '\n')
1431                                 break;
1432                         len++;
1433                 }
1434                 if (len >= table->maxlen)
1435                         len = table->maxlen-1;
1436                 if(copy_from_user(table->data, buffer, len))
1437                         return -EFAULT;
1438                 ((char *) table->data)[len] = 0;
1439                 *ppos += *lenp;
1440         } else {
1441                 len = strlen(table->data);
1442                 if (len > table->maxlen)
1443                         len = table->maxlen;
1444                 if (len > *lenp)
1445                         len = *lenp;
1446                 if (len)
1447                         if(copy_to_user(buffer, table->data, len))
1448                                 return -EFAULT;
1449                 if (len < *lenp) {
1450                         if(put_user('\n', ((char __user *) buffer) + len))
1451                                 return -EFAULT;
1452                         len++;
1453                 }
1454                 *lenp = len;
1455                 *ppos += len;
1456         }
1457         return 0;
1458 }
1459
1460 /*
1461  *      Special case of dostring for the UTS structure. This has locks
1462  *      to observe. Should this be in kernel/sys.c ????
1463  */
1464
1465 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
1466                   void __user *buffer, size_t *lenp, loff_t *ppos)
1467 {
1468         int r;
1469
1470         if (!write) {
1471                 down_read(&uts_sem);
1472                 r=proc_dostring(table,0,filp,buffer,lenp, ppos);
1473                 up_read(&uts_sem);
1474         } else {
1475                 down_write(&uts_sem);
1476                 r=proc_dostring(table,1,filp,buffer,lenp, ppos);
1477                 up_write(&uts_sem);
1478         }
1479         return r;
1480 }
1481
1482 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1483                                  int *valp,
1484                                  int write, void *data)
1485 {
1486         if (write) {
1487                 *valp = *negp ? -*lvalp : *lvalp;
1488         } else {
1489                 int val = *valp;
1490                 if (val < 0) {
1491                         *negp = -1;
1492                         *lvalp = (unsigned long)-val;
1493                 } else {
1494                         *negp = 0;
1495                         *lvalp = (unsigned long)val;
1496                 }
1497         }
1498         return 0;
1499 }
1500
1501 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1502                   void __user *buffer, size_t *lenp, loff_t *ppos,
1503                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1504                               int write, void *data),
1505                   void *data)
1506 {
1507 #define TMPBUFLEN 21
1508         int *i, vleft, first=1, neg, val;
1509         unsigned long lval;
1510         size_t left, len;
1511
1512         char buf[TMPBUFLEN], *p;
1513         char __user *s = buffer;
1514
1515         if (!table->data || !table->maxlen || !*lenp ||
1516             (*ppos && !write)) {
1517                 *lenp = 0;
1518                 return 0;
1519         }
1520
1521         i = (int *) table->data;
1522         vleft = table->maxlen / sizeof(*i);
1523         left = *lenp;
1524
1525         if (!conv)
1526                 conv = do_proc_dointvec_conv;
1527
1528         for (; left && vleft--; i++, first=0) {
1529                 if (write) {
1530                         while (left) {
1531                                 char c;
1532                                 if (get_user(c, s))
1533                                         return -EFAULT;
1534                                 if (!isspace(c))
1535                                         break;
1536                                 left--;
1537                                 s++;
1538                         }
1539                         if (!left)
1540                                 break;
1541                         neg = 0;
1542                         len = left;
1543                         if (len > sizeof(buf) - 1)
1544                                 len = sizeof(buf) - 1;
1545                         if (copy_from_user(buf, s, len))
1546                                 return -EFAULT;
1547                         buf[len] = 0;
1548                         p = buf;
1549                         if (*p == '-' && left > 1) {
1550                                 neg = 1;
1551                                 left--, p++;
1552                         }
1553                         if (*p < '0' || *p > '9')
1554                                 break;
1555
1556                         lval = simple_strtoul(p, &p, 0);
1557
1558                         len = p-buf;
1559                         if ((len < left) && *p && !isspace(*p))
1560                                 break;
1561                         if (neg)
1562                                 val = -val;
1563                         s += len;
1564                         left -= len;
1565
1566                         if (conv(&neg, &lval, i, 1, data))
1567                                 break;
1568                 } else {
1569                         p = buf;
1570                         if (!first)
1571                                 *p++ = '\t';
1572
1573                         if (conv(&neg, &lval, i, 0, data))
1574                                 break;
1575
1576                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
1577                         len = strlen(buf);
1578                         if (len > left)
1579                                 len = left;
1580                         if(copy_to_user(s, buf, len))
1581                                 return -EFAULT;
1582                         left -= len;
1583                         s += len;
1584                 }
1585         }
1586
1587         if (!write && !first && left) {
1588                 if(put_user('\n', s))
1589                         return -EFAULT;
1590                 left--, s++;
1591         }
1592         if (write) {
1593                 while (left) {
1594                         char c;
1595                         if (get_user(c, s++))
1596                                 return -EFAULT;
1597                         if (!isspace(c))
1598                                 break;
1599                         left--;
1600                 }
1601         }
1602         if (write && first)
1603                 return -EINVAL;
1604         *lenp -= left;
1605         *ppos += *lenp;
1606         return 0;
1607 #undef TMPBUFLEN
1608 }
1609
1610 /**
1611  * proc_dointvec - read a vector of integers
1612  * @table: the sysctl table
1613  * @write: %TRUE if this is a write to the sysctl file
1614  * @filp: the file structure
1615  * @buffer: the user buffer
1616  * @lenp: the size of the user buffer
1617  * @ppos: file position
1618  *
1619  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1620  * values from/to the user buffer, treated as an ASCII string.
1621  *
1622  * Returns 0 on success.
1623  */
1624 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1625                      void __user *buffer, size_t *lenp, loff_t *ppos)
1626 {
1627     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1628                             NULL,NULL);
1629 }
1630
1631 #define OP_SET  0
1632 #define OP_AND  1
1633 #define OP_OR   2
1634 #define OP_MAX  3
1635 #define OP_MIN  4
1636
1637 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1638                                       int *valp,
1639                                       int write, void *data)
1640 {
1641         int op = *(int *)data;
1642         if (write) {
1643                 int val = *negp ? -*lvalp : *lvalp;
1644                 switch(op) {
1645                 case OP_SET:    *valp = val; break;
1646                 case OP_AND:    *valp &= val; break;
1647                 case OP_OR:     *valp |= val; break;
1648                 case OP_MAX:    if(*valp < val)
1649                                         *valp = val;
1650                                 break;
1651                 case OP_MIN:    if(*valp > val)
1652                                 *valp = val;
1653                                 break;
1654                 }
1655         } else {
1656                 int val = *valp;
1657                 if (val < 0) {
1658                         *negp = -1;
1659                         *lvalp = (unsigned long)-val;
1660                 } else {
1661                         *negp = 0;
1662                         *lvalp = (unsigned long)val;
1663                 }
1664         }
1665         return 0;
1666 }
1667
1668 /*
1669  *      init may raise the set.
1670  */
1671
1672 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1673                         void __user *buffer, size_t *lenp, loff_t *ppos)
1674 {
1675         int op;
1676
1677         if (!capable(CAP_SYS_MODULE)) {
1678                 return -EPERM;
1679         }
1680
1681         op = (current->pid == 1) ? OP_SET : OP_AND;
1682         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1683                                 do_proc_dointvec_bset_conv,&op);
1684 }
1685
1686 struct do_proc_dointvec_minmax_conv_param {
1687         int *min;
1688         int *max;
1689 };
1690
1691 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1692                                         int *valp,
1693                                         int write, void *data)
1694 {
1695         struct do_proc_dointvec_minmax_conv_param *param = data;
1696         if (write) {
1697                 int val = *negp ? -*lvalp : *lvalp;
1698                 if ((param->min && *param->min > val) ||
1699                     (param->max && *param->max < val))
1700                         return -EINVAL;
1701                 *valp = val;
1702         } else {
1703                 int val = *valp;
1704                 if (val < 0) {
1705                         *negp = -1;
1706                         *lvalp = (unsigned long)-val;
1707                 } else {
1708                         *negp = 0;
1709                         *lvalp = (unsigned long)val;
1710                 }
1711         }
1712         return 0;
1713 }
1714
1715 /**
1716  * proc_dointvec_minmax - read a vector of integers with min/max values
1717  * @table: the sysctl table
1718  * @write: %TRUE if this is a write to the sysctl file
1719  * @filp: the file structure
1720  * @buffer: the user buffer
1721  * @lenp: the size of the user buffer
1722  * @ppos: file position
1723  *
1724  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1725  * values from/to the user buffer, treated as an ASCII string.
1726  *
1727  * This routine will ensure the values are within the range specified by
1728  * table->extra1 (min) and table->extra2 (max).
1729  *
1730  * Returns 0 on success.
1731  */
1732 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1733                   void __user *buffer, size_t *lenp, loff_t *ppos)
1734 {
1735         struct do_proc_dointvec_minmax_conv_param param = {
1736                 .min = (int *) table->extra1,
1737                 .max = (int *) table->extra2,
1738         };
1739         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1740                                 do_proc_dointvec_minmax_conv, &param);
1741 }
1742
1743 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1744                                      struct file *filp,
1745                                      void __user *buffer,
1746                                      size_t *lenp, loff_t *ppos,
1747                                      unsigned long convmul,
1748                                      unsigned long convdiv)
1749 {
1750 #define TMPBUFLEN 21
1751         unsigned long *i, *min, *max, val;
1752         int vleft, first=1, neg;
1753         size_t len, left;
1754         char buf[TMPBUFLEN], *p;
1755         char __user *s = buffer;
1756
1757         if (!table->data || !table->maxlen || !*lenp ||
1758             (*ppos && !write)) {
1759                 *lenp = 0;
1760                 return 0;
1761         }
1762
1763         i = (unsigned long *) table->data;
1764         min = (unsigned long *) table->extra1;
1765         max = (unsigned long *) table->extra2;
1766         vleft = table->maxlen / sizeof(unsigned long);
1767         left = *lenp;
1768
1769         for (; left && vleft--; i++, min++, max++, first=0) {
1770                 if (write) {
1771                         while (left) {
1772                                 char c;
1773                                 if (get_user(c, s))
1774                                         return -EFAULT;
1775                                 if (!isspace(c))
1776                                         break;
1777                                 left--;
1778                                 s++;
1779                         }
1780                         if (!left)
1781                                 break;
1782                         neg = 0;
1783                         len = left;
1784                         if (len > TMPBUFLEN-1)
1785                                 len = TMPBUFLEN-1;
1786                         if (copy_from_user(buf, s, len))
1787                                 return -EFAULT;
1788                         buf[len] = 0;
1789                         p = buf;
1790                         if (*p == '-' && left > 1) {
1791                                 neg = 1;
1792                                 left--, p++;
1793                         }
1794                         if (*p < '0' || *p > '9')
1795                                 break;
1796                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1797                         len = p-buf;
1798                         if ((len < left) && *p && !isspace(*p))
1799                                 break;
1800                         if (neg)
1801                                 val = -val;
1802                         s += len;
1803                         left -= len;
1804
1805                         if(neg)
1806                                 continue;
1807                         if ((min && val < *min) || (max && val > *max))
1808                                 continue;
1809                         *i = val;
1810                 } else {
1811                         p = buf;
1812                         if (!first)
1813                                 *p++ = '\t';
1814                         sprintf(p, "%lu", convdiv * (*i) / convmul);
1815                         len = strlen(buf);
1816                         if (len > left)
1817                                 len = left;
1818                         if(copy_to_user(s, buf, len))
1819                                 return -EFAULT;
1820                         left -= len;
1821                         s += len;
1822                 }
1823         }
1824
1825         if (!write && !first && left) {
1826                 if(put_user('\n', s))
1827                         return -EFAULT;
1828                 left--, s++;
1829         }
1830         if (write) {
1831                 while (left) {
1832                         char c;
1833                         if (get_user(c, s++))
1834                                 return -EFAULT;
1835                         if (!isspace(c))
1836                                 break;
1837                         left--;
1838                 }
1839         }
1840         if (write && first)
1841                 return -EINVAL;
1842         *lenp -= left;
1843         *ppos += *lenp;
1844         return 0;
1845 #undef TMPBUFLEN
1846 }
1847
1848 /**
1849  * proc_doulongvec_minmax - read a vector of long integers with min/max values
1850  * @table: the sysctl table
1851  * @write: %TRUE if this is a write to the sysctl file
1852  * @filp: the file structure
1853  * @buffer: the user buffer
1854  * @lenp: the size of the user buffer
1855  * @ppos: file position
1856  *
1857  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1858  * values from/to the user buffer, treated as an ASCII string.
1859  *
1860  * This routine will ensure the values are within the range specified by
1861  * table->extra1 (min) and table->extra2 (max).
1862  *
1863  * Returns 0 on success.
1864  */
1865 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
1866                            void __user *buffer, size_t *lenp, loff_t *ppos)
1867 {
1868     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
1869 }
1870
1871 /**
1872  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
1873  * @table: the sysctl table
1874  * @write: %TRUE if this is a write to the sysctl file
1875  * @filp: the file structure
1876  * @buffer: the user buffer
1877  * @lenp: the size of the user buffer
1878  * @ppos: file position
1879  *
1880  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1881  * values from/to the user buffer, treated as an ASCII string. The values
1882  * are treated as milliseconds, and converted to jiffies when they are stored.
1883  *
1884  * This routine will ensure the values are within the range specified by
1885  * table->extra1 (min) and table->extra2 (max).
1886  *
1887  * Returns 0 on success.
1888  */
1889 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
1890                                       struct file *filp,
1891                                       void __user *buffer,
1892                                       size_t *lenp, loff_t *ppos)
1893 {
1894     return do_proc_doulongvec_minmax(table, write, filp, buffer,
1895                                      lenp, ppos, HZ, 1000l);
1896 }
1897
1898
1899 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
1900                                          int *valp,
1901                                          int write, void *data)
1902 {
1903         if (write) {
1904                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
1905         } else {
1906                 int val = *valp;
1907                 unsigned long lval;
1908                 if (val < 0) {
1909                         *negp = -1;
1910                         lval = (unsigned long)-val;
1911                 } else {
1912                         *negp = 0;
1913                         lval = (unsigned long)val;
1914                 }
1915                 *lvalp = lval / HZ;
1916         }
1917         return 0;
1918 }
1919
1920 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
1921                                                 int *valp,
1922                                                 int write, void *data)
1923 {
1924         if (write) {
1925                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
1926         } else {
1927                 int val = *valp;
1928                 unsigned long lval;
1929                 if (val < 0) {
1930                         *negp = -1;
1931                         lval = (unsigned long)-val;
1932                 } else {
1933                         *negp = 0;
1934                         lval = (unsigned long)val;
1935                 }
1936                 *lvalp = jiffies_to_clock_t(lval);
1937         }
1938         return 0;
1939 }
1940
1941 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
1942                                             int *valp,
1943                                             int write, void *data)
1944 {
1945         if (write) {
1946                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
1947         } else {
1948                 int val = *valp;
1949                 unsigned long lval;
1950                 if (val < 0) {
1951                         *negp = -1;
1952                         lval = (unsigned long)-val;
1953                 } else {
1954                         *negp = 0;
1955                         lval = (unsigned long)val;
1956                 }
1957                 *lvalp = jiffies_to_msecs(lval);
1958         }
1959         return 0;
1960 }
1961
1962 /**
1963  * proc_dointvec_jiffies - read a vector of integers as seconds
1964  * @table: the sysctl table
1965  * @write: %TRUE if this is a write to the sysctl file
1966  * @filp: the file structure
1967  * @buffer: the user buffer
1968  * @lenp: the size of the user buffer
1969  * @ppos: file position
1970  *
1971  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1972  * values from/to the user buffer, treated as an ASCII string.
1973  * The values read are assumed to be in seconds, and are converted into
1974  * jiffies.
1975  *
1976  * Returns 0 on success.
1977  */
1978 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
1979                           void __user *buffer, size_t *lenp, loff_t *ppos)
1980 {
1981     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1982                             do_proc_dointvec_jiffies_conv,NULL);
1983 }
1984
1985 /**
1986  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
1987  * @table: the sysctl table
1988  * @write: %TRUE if this is a write to the sysctl file
1989  * @filp: the file structure
1990  * @buffer: the user buffer
1991  * @lenp: the size of the user buffer
1992  *
1993  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1994  * values from/to the user buffer, treated as an ASCII string.
1995  * The values read are assumed to be in 1/USER_HZ seconds, and
1996  * are converted into jiffies.
1997  *
1998  * Returns 0 on success.
1999  */
2000 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2001                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2002 {
2003     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2004                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2005 }
2006
2007 /**
2008  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2009  * @table: the sysctl table
2010  * @write: %TRUE if this is a write to the sysctl file
2011  * @filp: the file structure
2012  * @buffer: the user buffer
2013  * @lenp: the size of the user buffer
2014  * @ppos: file position
2015  * @ppos: the current position in the file
2016  *
2017  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2018  * values from/to the user buffer, treated as an ASCII string.
2019  * The values read are assumed to be in 1/1000 seconds, and
2020  * are converted into jiffies.
2021  *
2022  * Returns 0 on success.
2023  */
2024 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2025                              void __user *buffer, size_t *lenp, loff_t *ppos)
2026 {
2027         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2028                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2029 }
2030
2031 #else /* CONFIG_PROC_FS */
2032
2033 int proc_dostring(ctl_table *table, int write, struct file *filp,
2034                   void __user *buffer, size_t *lenp, loff_t *ppos)
2035 {
2036         return -ENOSYS;
2037 }
2038
2039 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
2040                             void __user *buffer, size_t *lenp, loff_t *ppos)
2041 {
2042         return -ENOSYS;
2043 }
2044
2045 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2046                   void __user *buffer, size_t *lenp, loff_t *ppos)
2047 {
2048         return -ENOSYS;
2049 }
2050
2051 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2052                         void __user *buffer, size_t *lenp, loff_t *ppos)
2053 {
2054         return -ENOSYS;
2055 }
2056
2057 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2058                     void __user *buffer, size_t *lenp, loff_t *ppos)
2059 {
2060         return -ENOSYS;
2061 }
2062
2063 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2064                     void __user *buffer, size_t *lenp, loff_t *ppos)
2065 {
2066         return -ENOSYS;
2067 }
2068
2069 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2070                     void __user *buffer, size_t *lenp, loff_t *ppos)
2071 {
2072         return -ENOSYS;
2073 }
2074
2075 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2076                              void __user *buffer, size_t *lenp, loff_t *ppos)
2077 {
2078         return -ENOSYS;
2079 }
2080
2081 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2082                     void __user *buffer, size_t *lenp, loff_t *ppos)
2083 {
2084         return -ENOSYS;
2085 }
2086
2087 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2088                                       struct file *filp,
2089                                       void __user *buffer,
2090                                       size_t *lenp, loff_t *ppos)
2091 {
2092     return -ENOSYS;
2093 }
2094
2095
2096 #endif /* CONFIG_PROC_FS */
2097
2098
2099 /*
2100  * General sysctl support routines
2101  */
2102
2103 /* The generic string strategy routine: */
2104 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2105                   void __user *oldval, size_t __user *oldlenp,
2106                   void __user *newval, size_t newlen, void **context)
2107 {
2108         size_t l, len;
2109
2110         if (!table->data || !table->maxlen)
2111                 return -ENOTDIR;
2112
2113         if (oldval && oldlenp) {
2114                 if (get_user(len, oldlenp))
2115                         return -EFAULT;
2116                 if (len) {
2117                         l = strlen(table->data);
2118                         if (len > l) len = l;
2119                         if (len >= table->maxlen)
2120                                 len = table->maxlen;
2121                         if(copy_to_user(oldval, table->data, len))
2122                                 return -EFAULT;
2123                         if(put_user(0, ((char __user *) oldval) + len))
2124                                 return -EFAULT;
2125                         if(put_user(len, oldlenp))
2126                                 return -EFAULT;
2127                 }
2128         }
2129         if (newval && newlen) {
2130                 len = newlen;
2131                 if (len > table->maxlen)
2132                         len = table->maxlen;
2133                 if(copy_from_user(table->data, newval, len))
2134                         return -EFAULT;
2135                 if (len == table->maxlen)
2136                         len--;
2137                 ((char *) table->data)[len] = 0;
2138         }
2139         return 0;
2140 }
2141
2142 /*
2143  * This function makes sure that all of the integers in the vector
2144  * are between the minimum and maximum values given in the arrays
2145  * table->extra1 and table->extra2, respectively.
2146  */
2147 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2148                 void __user *oldval, size_t __user *oldlenp,
2149                 void __user *newval, size_t newlen, void **context)
2150 {
2151
2152         if (newval && newlen) {
2153                 int __user *vec = (int __user *) newval;
2154                 int *min = (int *) table->extra1;
2155                 int *max = (int *) table->extra2;
2156                 size_t length;
2157                 int i;
2158
2159                 if (newlen % sizeof(int) != 0)
2160                         return -EINVAL;
2161
2162                 if (!table->extra1 && !table->extra2)
2163                         return 0;
2164
2165                 if (newlen > table->maxlen)
2166                         newlen = table->maxlen;
2167                 length = newlen / sizeof(int);
2168
2169                 for (i = 0; i < length; i++) {
2170                         int value;
2171                         if (get_user(value, vec + i))
2172                                 return -EFAULT;
2173                         if (min && value < min[i])
2174                                 return -EINVAL;
2175                         if (max && value > max[i])
2176                                 return -EINVAL;
2177                 }
2178         }
2179         return 0;
2180 }
2181
2182 /* Strategy function to convert jiffies to seconds */
2183 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2184                 void __user *oldval, size_t __user *oldlenp,
2185                 void __user *newval, size_t newlen, void **context)
2186 {
2187         if (oldval) {
2188                 size_t olen;
2189                 if (oldlenp) {
2190                         if (get_user(olen, oldlenp))
2191                                 return -EFAULT;
2192                         if (olen!=sizeof(int))
2193                                 return -EINVAL;
2194                 }
2195                 if (put_user(*(int *)(table->data)/HZ, (int __user *)oldval) ||
2196                     (oldlenp && put_user(sizeof(int),oldlenp)))
2197                         return -EFAULT;
2198         }
2199         if (newval && newlen) {
2200                 int new;
2201                 if (newlen != sizeof(int))
2202                         return -EINVAL;
2203                 if (get_user(new, (int __user *)newval))
2204                         return -EFAULT;
2205                 *(int *)(table->data) = new*HZ;
2206         }
2207         return 1;
2208 }
2209
2210 /* Strategy function to convert jiffies to seconds */
2211 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2212                 void __user *oldval, size_t __user *oldlenp,
2213                 void __user *newval, size_t newlen, void **context)
2214 {
2215         if (oldval) {
2216                 size_t olen;
2217                 if (oldlenp) {
2218                         if (get_user(olen, oldlenp))
2219                                 return -EFAULT;
2220                         if (olen!=sizeof(int))
2221                                 return -EINVAL;
2222                 }
2223                 if (put_user(jiffies_to_msecs(*(int *)(table->data)), (int __user *)oldval) ||
2224                     (oldlenp && put_user(sizeof(int),oldlenp)))
2225                         return -EFAULT;
2226         }
2227         if (newval && newlen) {
2228                 int new;
2229                 if (newlen != sizeof(int))
2230                         return -EINVAL;
2231                 if (get_user(new, (int __user *)newval))
2232                         return -EFAULT;
2233                 *(int *)(table->data) = msecs_to_jiffies(new);
2234         }
2235         return 1;
2236 }
2237
2238 #else /* CONFIG_SYSCTL */
2239
2240
2241 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2242 {
2243         return -ENOSYS;
2244 }
2245
2246 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2247                   void __user *oldval, size_t __user *oldlenp,
2248                   void __user *newval, size_t newlen, void **context)
2249 {
2250         return -ENOSYS;
2251 }
2252
2253 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2254                 void __user *oldval, size_t __user *oldlenp,
2255                 void __user *newval, size_t newlen, void **context)
2256 {
2257         return -ENOSYS;
2258 }
2259
2260 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2261                 void __user *oldval, size_t __user *oldlenp,
2262                 void __user *newval, size_t newlen, void **context)
2263 {
2264         return -ENOSYS;
2265 }
2266
2267 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2268                 void __user *oldval, size_t __user *oldlenp,
2269                 void __user *newval, size_t newlen, void **context)
2270 {
2271         return -ENOSYS;
2272 }
2273
2274 int proc_dostring(ctl_table *table, int write, struct file *filp,
2275                   void __user *buffer, size_t *lenp, loff_t *ppos)
2276 {
2277         return -ENOSYS;
2278 }
2279
2280 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2281                   void __user *buffer, size_t *lenp, loff_t *ppos)
2282 {
2283         return -ENOSYS;
2284 }
2285
2286 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2287                         void __user *buffer, size_t *lenp, loff_t *ppos)
2288 {
2289         return -ENOSYS;
2290 }
2291
2292 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2293                     void __user *buffer, size_t *lenp, loff_t *ppos)
2294 {
2295         return -ENOSYS;
2296 }
2297
2298 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2299                           void __user *buffer, size_t *lenp, loff_t *ppos)
2300 {
2301         return -ENOSYS;
2302 }
2303
2304 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2305                           void __user *buffer, size_t *lenp, loff_t *ppos)
2306 {
2307         return -ENOSYS;
2308 }
2309
2310 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2311                              void __user *buffer, size_t *lenp, loff_t *ppos)
2312 {
2313         return -ENOSYS;
2314 }
2315
2316 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2317                     void __user *buffer, size_t *lenp, loff_t *ppos)
2318 {
2319         return -ENOSYS;
2320 }
2321
2322 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2323                                       struct file *filp,
2324                                       void __user *buffer,
2325                                       size_t *lenp, loff_t *ppos)
2326 {
2327     return -ENOSYS;
2328 }
2329
2330 struct ctl_table_header * register_sysctl_table(ctl_table * table,
2331                                                 int insert_at_head)
2332 {
2333         return NULL;
2334 }
2335
2336 void unregister_sysctl_table(struct ctl_table_header * table)
2337 {
2338 }
2339
2340 #endif /* CONFIG_SYSCTL */
2341
2342 /*
2343  * No sense putting this after each symbol definition, twice,
2344  * exception granted :-)
2345  */
2346 EXPORT_SYMBOL(proc_dointvec);
2347 EXPORT_SYMBOL(proc_dointvec_jiffies);
2348 EXPORT_SYMBOL(proc_dointvec_minmax);
2349 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2350 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2351 EXPORT_SYMBOL(proc_dostring);
2352 EXPORT_SYMBOL(proc_doulongvec_minmax);
2353 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2354 EXPORT_SYMBOL(register_sysctl_table);
2355 EXPORT_SYMBOL(sysctl_intvec);
2356 EXPORT_SYMBOL(sysctl_jiffies);
2357 EXPORT_SYMBOL(sysctl_ms_jiffies);
2358 EXPORT_SYMBOL(sysctl_string);
2359 EXPORT_SYMBOL(unregister_sysctl_table);