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/net.h>
  35 #include <linux/sysrq.h>
  36 #include <linux/highuid.h>
  37 #include <linux/writeback.h>
  38 #include <linux/hugetlb.h>
  39 #include <linux/security.h>
  40 #include <linux/initrd.h>
  41 #include <linux/times.h>
  42 #include <linux/limits.h>
  43 #include <linux/dcache.h>
  44 #include <linux/syscalls.h>
  45
  46 #include <asm/uaccess.h>
  47 #include <asm/processor.h>
  48
  49 #ifdef CONFIG_ROOT_NFS
  50 #include <linux/nfs_fs.h>
  51 #endif
  52
  53 #if defined(CONFIG_SYSCTL)
  54
  55 /* External variables not in a header file. */
  56 extern int C_A_D;
  57 extern int sysctl_overcommit_memory;
  58 extern int sysctl_overcommit_ratio;
  59 extern int max_threads;
  60 extern int sysrq_enabled;
  61 extern int core_uses_pid;
  62 extern int suid_dumpable;
  63 extern char core_pattern[];
  64 extern int cad_pid;
  65 extern int pid_max;
  66 extern int min_free_kbytes;
  67 extern int printk_ratelimit_jiffies;
  68 extern int printk_ratelimit_burst;
  69 extern int pid_max_min, pid_max_max;
  70
  71 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
  72 int unknown_nmi_panic;
  73 extern int proc_unknown_nmi_panic(ctl_table *, int, struct file *,
  74                                   void __user *, size_t *, loff_t *);
  75 #endif
  76
  77 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
  78 static int maxolduid = 65535;
  79 static int minolduid;
  80
  81 static int ngroups_max = NGROUPS_MAX;
  82
  83 #ifdef CONFIG_KMOD
  84 extern char modprobe_path[];
  85 #endif
  86 #ifdef CONFIG_HOTPLUG
  87 extern char hotplug_path[];
  88 #endif
  89 #ifdef CONFIG_CHR_DEV_SG
  90 extern int sg_big_buff;
  91 #endif
  92 #ifdef CONFIG_SYSVIPC
  93 extern size_t shm_ctlmax;
  94 extern size_t shm_ctlall;
  95 extern int shm_ctlmni;
  96 extern int msg_ctlmax;
  97 extern int msg_ctlmnb;
  98 extern int msg_ctlmni;
  99 extern int sem_ctls[];
 100 #endif
 101
 102 #ifdef __sparc__
 103 extern char reboot_command [];
 104 extern int stop_a_enabled;
 105 extern int scons_pwroff;
 106 #endif
 107
 108 #ifdef __hppa__
 109 extern int pwrsw_enabled;
 110 extern int unaligned_enabled;
 111 #endif
 112
 113 #ifdef CONFIG_ARCH_S390
 114 #ifdef CONFIG_MATHEMU
 115 extern int sysctl_ieee_emulation_warnings;
 116 #endif
 117 extern int sysctl_userprocess_debug;
 118 extern int spin_retry;
 119 #endif
 120
 121 extern int sysctl_hz_timer;
 122
 123 #ifdef CONFIG_BSD_PROCESS_ACCT
 124 extern int acct_parm[];
 125 #endif
 126
 127 int randomize_va_space = 1;
 128
 129 static int parse_table(int __user *, int, void __user *, size_t __user *, void __user *, size_t,
 130                        ctl_table *, void **);
 131 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
 132                   void __user *buffer, size_t *lenp, loff_t *ppos);
 133
 134 static ctl_table root_table[];
 135 static struct ctl_table_header root_table_header =
 136         { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
 137
 138 static ctl_table kern_table[];
 139 static ctl_table vm_table[];
 140 static ctl_table proc_table[];
 141 static ctl_table fs_table[];
 142 static ctl_table debug_table[];
 143 static ctl_table dev_table[];
 144 extern ctl_table random_table[];
 145 #ifdef CONFIG_UNIX98_PTYS
 146 extern ctl_table pty_table[];
 147 #endif
 148 #ifdef CONFIG_INOTIFY
 149 extern ctl_table inotify_table[];
 150 #endif
 151
 152 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 153 int sysctl_legacy_va_layout;
 154 #endif
 155
 156 /* /proc declarations: */
 157
 158 #ifdef CONFIG_PROC_FS
 159
 160 static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
 161 static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
 162 static int proc_opensys(struct inode *, struct file *);
 163
 164 struct file_operations proc_sys_file_operations = {
 165         .open           = proc_opensys,
 166         .read           = proc_readsys,
 167         .write          = proc_writesys,
 168 };
 169
 170 extern struct proc_dir_entry *proc_sys_root;
 171
 172 static void register_proc_table(ctl_table *, struct proc_dir_entry *, void *);
 173 static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
 174 #endif
 175
 176 /* The default sysctl tables: */
 177
 178 static ctl_table root_table[] = {
 179         {
 180                 .ctl_name       = CTL_KERN,
 181                 .procname       = "kernel",
 182                 .mode           = 0555,
 183                 .child          = kern_table,
 184         },
 185         {
 186                 .ctl_name       = CTL_VM,
 187                 .procname       = "vm",
 188                 .mode           = 0555,
 189                 .child          = vm_table,
 190         },
 191 #ifdef CONFIG_NET
 192         {
 193                 .ctl_name       = CTL_NET,
 194                 .procname       = "net",
 195                 .mode           = 0555,
 196                 .child          = net_table,
 197         },
 198 #endif
 199         {
 200                 .ctl_name       = CTL_PROC,
 201                 .procname       = "proc",
 202                 .mode           = 0555,
 203                 .child          = proc_table,
 204         },
 205         {
 206                 .ctl_name       = CTL_FS,
 207                 .procname       = "fs",
 208                 .mode           = 0555,
 209                 .child          = fs_table,
 210         },
 211         {
 212                 .ctl_name       = CTL_DEBUG,
 213                 .procname       = "debug",
 214                 .mode           = 0555,
 215                 .child          = debug_table,
 216         },
 217         {
 218                 .ctl_name       = CTL_DEV,
 219                 .procname       = "dev",
 220                 .mode           = 0555,
 221                 .child          = dev_table,
 222         },
 223
 224         { .ctl_name = 0 }
 225 };
 226
 227 static ctl_table kern_table[] = {
 228         {
 229                 .ctl_name       = KERN_OSTYPE,
 230                 .procname       = "ostype",
 231                 .data           = system_utsname.sysname,
 232                 .maxlen         = sizeof(system_utsname.sysname),
 233                 .mode           = 0444,
 234                 .proc_handler   = &proc_doutsstring,
 235                 .strategy       = &sysctl_string,
 236         },
 237         {
 238                 .ctl_name       = KERN_OSRELEASE,
 239                 .procname       = "osrelease",
 240                 .data           = system_utsname.release,
 241                 .maxlen         = sizeof(system_utsname.release),
 242                 .mode           = 0444,
 243                 .proc_handler   = &proc_doutsstring,
 244                 .strategy       = &sysctl_string,
 245         },
 246         {
 247                 .ctl_name       = KERN_VERSION,
 248                 .procname       = "version",
 249                 .data           = system_utsname.version,
 250                 .maxlen         = sizeof(system_utsname.version),
 251                 .mode           = 0444,
 252                 .proc_handler   = &proc_doutsstring,
 253                 .strategy       = &sysctl_string,
 254         },
 255         {
 256                 .ctl_name       = KERN_NODENAME,
 257                 .procname       = "hostname",
 258                 .data           = system_utsname.nodename,
 259                 .maxlen         = sizeof(system_utsname.nodename),
 260                 .mode           = 0644,
 261                 .proc_handler   = &proc_doutsstring,
 262                 .strategy       = &sysctl_string,
 263         },
 264         {
 265                 .ctl_name       = KERN_DOMAINNAME,
 266                 .procname       = "domainname",
 267                 .data           = system_utsname.domainname,
 268                 .maxlen         = sizeof(system_utsname.domainname),
 269                 .mode           = 0644,
 270                 .proc_handler   = &proc_doutsstring,
 271                 .strategy       = &sysctl_string,
 272         },
 273         {
 274                 .ctl_name       = KERN_PANIC,
 275                 .procname       = "panic",
 276                 .data           = &panic_timeout,
 277                 .maxlen         = sizeof(int),
 278                 .mode           = 0644,
 279                 .proc_handler   = &proc_dointvec,
 280         },
 281         {
 282                 .ctl_name       = KERN_CORE_USES_PID,
 283                 .procname       = "core_uses_pid",
 284                 .data           = &core_uses_pid,
 285                 .maxlen         = sizeof(int),
 286                 .mode           = 0644,
 287                 .proc_handler   = &proc_dointvec,
 288         },
 289         {
 290                 .ctl_name       = KERN_CORE_PATTERN,
 291                 .procname       = "core_pattern",
 292                 .data           = core_pattern,
 293                 .maxlen         = 64,
 294                 .mode           = 0644,
 295                 .proc_handler   = &proc_dostring,
 296                 .strategy       = &sysctl_string,
 297         },
 298         {
 299                 .ctl_name       = KERN_TAINTED,
 300                 .procname       = "tainted",
 301                 .data           = &tainted,
 302                 .maxlen         = sizeof(int),
 303                 .mode           = 0444,
 304                 .proc_handler   = &proc_dointvec,
 305         },
 306         {
 307                 .ctl_name       = KERN_CAP_BSET,
 308                 .procname       = "cap-bound",
 309                 .data           = &cap_bset,
 310                 .maxlen         = sizeof(kernel_cap_t),
 311                 .mode           = 0600,
 312                 .proc_handler   = &proc_dointvec_bset,
 313         },
 314 #ifdef CONFIG_BLK_DEV_INITRD
 315         {
 316                 .ctl_name       = KERN_REALROOTDEV,
 317                 .procname       = "real-root-dev",
 318                 .data           = &real_root_dev,
 319                 .maxlen         = sizeof(int),
 320                 .mode           = 0644,
 321                 .proc_handler   = &proc_dointvec,
 322         },
 323 #endif
 324 #ifdef __sparc__
 325         {
 326                 .ctl_name       = KERN_SPARC_REBOOT,
 327                 .procname       = "reboot-cmd",
 328                 .data           = reboot_command,
 329                 .maxlen         = 256,
 330                 .mode           = 0644,
 331                 .proc_handler   = &proc_dostring,
 332                 .strategy       = &sysctl_string,
 333         },
 334         {
 335                 .ctl_name       = KERN_SPARC_STOP_A,
 336                 .procname       = "stop-a",
 337                 .data           = &stop_a_enabled,
 338                 .maxlen         = sizeof (int),
 339                 .mode           = 0644,
 340                 .proc_handler   = &proc_dointvec,
 341         },
 342         {
 343                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 344                 .procname       = "scons-poweroff",
 345                 .data           = &scons_pwroff,
 346                 .maxlen         = sizeof (int),
 347                 .mode           = 0644,
 348                 .proc_handler   = &proc_dointvec,
 349         },
 350 #endif
 351 #ifdef __hppa__
 352         {
 353                 .ctl_name       = KERN_HPPA_PWRSW,
 354                 .procname       = "soft-power",
 355                 .data           = &pwrsw_enabled,
 356                 .maxlen         = sizeof (int),
 357                 .mode           = 0644,
 358                 .proc_handler   = &proc_dointvec,
 359         },
 360         {
 361                 .ctl_name       = KERN_HPPA_UNALIGNED,
 362                 .procname       = "unaligned-trap",
 363                 .data           = &unaligned_enabled,
 364                 .maxlen         = sizeof (int),
 365                 .mode           = 0644,
 366                 .proc_handler   = &proc_dointvec,
 367         },
 368 #endif
 369         {
 370                 .ctl_name       = KERN_CTLALTDEL,
 371                 .procname       = "ctrl-alt-del",
 372                 .data           = &C_A_D,
 373                 .maxlen         = sizeof(int),
 374                 .mode           = 0644,
 375                 .proc_handler   = &proc_dointvec,
 376         },
 377         {
 378                 .ctl_name       = KERN_PRINTK,
 379                 .procname       = "printk",
 380                 .data           = &console_loglevel,
 381                 .maxlen         = 4*sizeof(int),
 382                 .mode           = 0644,
 383                 .proc_handler   = &proc_dointvec,
 384         },
 385 #ifdef CONFIG_KMOD
 386         {
 387                 .ctl_name       = KERN_MODPROBE,
 388                 .procname       = "modprobe",
 389                 .data           = &modprobe_path,
 390                 .maxlen         = KMOD_PATH_LEN,
 391                 .mode           = 0644,
 392                 .proc_handler   = &proc_dostring,
 393                 .strategy       = &sysctl_string,
 394         },
 395 #endif
 396 #ifdef CONFIG_HOTPLUG
 397         {
 398                 .ctl_name       = KERN_HOTPLUG,
 399                 .procname       = "hotplug",
 400                 .data           = &hotplug_path,
 401                 .maxlen         = HOTPLUG_PATH_LEN,
 402                 .mode           = 0644,
 403                 .proc_handler   = &proc_dostring,
 404                 .strategy       = &sysctl_string,
 405         },
 406 #endif
 407 #ifdef CONFIG_CHR_DEV_SG
 408         {
 409                 .ctl_name       = KERN_SG_BIG_BUFF,
 410                 .procname       = "sg-big-buff",
 411                 .data           = &sg_big_buff,
 412                 .maxlen         = sizeof (int),
 413                 .mode           = 0444,
 414                 .proc_handler   = &proc_dointvec,
 415         },
 416 #endif
 417 #ifdef CONFIG_BSD_PROCESS_ACCT
 418         {
 419                 .ctl_name       = KERN_ACCT,
 420                 .procname       = "acct",
 421                 .data           = &acct_parm,
 422                 .maxlen         = 3*sizeof(int),
 423                 .mode           = 0644,
 424                 .proc_handler   = &proc_dointvec,
 425         },
 426 #endif
 427 #ifdef CONFIG_SYSVIPC
 428         {
 429                 .ctl_name       = KERN_SHMMAX,
 430                 .procname       = "shmmax",
 431                 .data           = &shm_ctlmax,
 432                 .maxlen         = sizeof (size_t),
 433                 .mode           = 0644,
 434                 .proc_handler   = &proc_doulongvec_minmax,
 435         },
 436         {
 437                 .ctl_name       = KERN_SHMALL,
 438                 .procname       = "shmall",
 439                 .data           = &shm_ctlall,
 440                 .maxlen         = sizeof (size_t),
 441                 .mode           = 0644,
 442                 .proc_handler   = &proc_doulongvec_minmax,
 443         },
 444         {
 445                 .ctl_name       = KERN_SHMMNI,
 446                 .procname       = "shmmni",
 447                 .data           = &shm_ctlmni,
 448                 .maxlen         = sizeof (int),
 449                 .mode           = 0644,
 450                 .proc_handler   = &proc_dointvec,
 451         },
 452         {
 453                 .ctl_name       = KERN_MSGMAX,
 454                 .procname       = "msgmax",
 455                 .data           = &msg_ctlmax,
 456                 .maxlen         = sizeof (int),
 457                 .mode           = 0644,
 458                 .proc_handler   = &proc_dointvec,
 459         },
 460         {
 461                 .ctl_name       = KERN_MSGMNI,
 462                 .procname       = "msgmni",
 463                 .data           = &msg_ctlmni,
 464                 .maxlen         = sizeof (int),
 465                 .mode           = 0644,
 466                 .proc_handler   = &proc_dointvec,
 467         },
 468         {
 469                 .ctl_name       = KERN_MSGMNB,
 470                 .procname       =  "msgmnb",
 471                 .data           = &msg_ctlmnb,
 472                 .maxlen         = sizeof (int),
 473                 .mode           = 0644,
 474                 .proc_handler   = &proc_dointvec,
 475         },
 476         {
 477                 .ctl_name       = KERN_SEM,
 478                 .procname       = "sem",
 479                 .data           = &sem_ctls,
 480                 .maxlen         = 4*sizeof (int),
 481                 .mode           = 0644,
 482                 .proc_handler   = &proc_dointvec,
 483         },
 484 #endif
 485 #ifdef CONFIG_MAGIC_SYSRQ
 486         {
 487                 .ctl_name       = KERN_SYSRQ,
 488                 .procname       = "sysrq",
 489                 .data           = &sysrq_enabled,
 490                 .maxlen         = sizeof (int),
 491                 .mode           = 0644,
 492                 .proc_handler   = &proc_dointvec,
 493         },
 494 #endif
 495         {
 496                 .ctl_name       = KERN_CADPID,
 497                 .procname       = "cad_pid",
 498                 .data           = &cad_pid,
 499                 .maxlen         = sizeof (int),
 500                 .mode           = 0600,
 501                 .proc_handler   = &proc_dointvec,
 502         },
 503         {
 504                 .ctl_name       = KERN_MAX_THREADS,
 505                 .procname       = "threads-max",
 506                 .data           = &max_threads,
 507                 .maxlen         = sizeof(int),
 508                 .mode           = 0644,
 509                 .proc_handler   = &proc_dointvec,
 510         },
 511         {
 512                 .ctl_name       = KERN_RANDOM,
 513                 .procname       = "random",
 514                 .mode           = 0555,
 515                 .child          = random_table,
 516         },
 517 #ifdef CONFIG_UNIX98_PTYS
 518         {
 519                 .ctl_name       = KERN_PTY,
 520                 .procname       = "pty",
 521                 .mode           = 0555,
 522                 .child          = pty_table,
 523         },
 524 #endif
 525         {
 526                 .ctl_name       = KERN_OVERFLOWUID,
 527                 .procname       = "overflowuid",
 528                 .data           = &overflowuid,
 529                 .maxlen         = sizeof(int),
 530                 .mode           = 0644,
 531                 .proc_handler   = &proc_dointvec_minmax,
 532                 .strategy       = &sysctl_intvec,
 533                 .extra1         = &minolduid,
 534                 .extra2         = &maxolduid,
 535         },
 536         {
 537                 .ctl_name       = KERN_OVERFLOWGID,
 538                 .procname       = "overflowgid",
 539                 .data           = &overflowgid,
 540                 .maxlen         = sizeof(int),
 541                 .mode           = 0644,
 542                 .proc_handler   = &proc_dointvec_minmax,
 543                 .strategy       = &sysctl_intvec,
 544                 .extra1         = &minolduid,
 545                 .extra2         = &maxolduid,
 546         },
 547 #ifdef CONFIG_ARCH_S390
 548 #ifdef CONFIG_MATHEMU
 549         {
 550                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 551                 .procname       = "ieee_emulation_warnings",
 552                 .data           = &sysctl_ieee_emulation_warnings,
 553                 .maxlen         = sizeof(int),
 554                 .mode           = 0644,
 555                 .proc_handler   = &proc_dointvec,
 556         },
 557 #endif
 558 #ifdef CONFIG_NO_IDLE_HZ
 559         {
 560                 .ctl_name       = KERN_HZ_TIMER,
 561                 .procname       = "hz_timer",
 562                 .data           = &sysctl_hz_timer,
 563                 .maxlen         = sizeof(int),
 564                 .mode           = 0644,
 565                 .proc_handler   = &proc_dointvec,
 566         },
 567 #endif
 568         {
 569                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 570                 .procname       = "userprocess_debug",
 571                 .data           = &sysctl_userprocess_debug,
 572                 .maxlen         = sizeof(int),
 573                 .mode           = 0644,
 574                 .proc_handler   = &proc_dointvec,
 575         },
 576 #endif
 577         {
 578                 .ctl_name       = KERN_PIDMAX,
 579                 .procname       = "pid_max",
 580                 .data           = &pid_max,
 581                 .maxlen         = sizeof (int),
 582                 .mode           = 0644,
 583                 .proc_handler   = &proc_dointvec_minmax,
 584                 .strategy       = sysctl_intvec,
 585                 .extra1         = &pid_max_min,
 586                 .extra2         = &pid_max_max,
 587         },
 588         {
 589                 .ctl_name       = KERN_PANIC_ON_OOPS,
 590                 .procname       = "panic_on_oops",
 591                 .data           = &panic_on_oops,
 592                 .maxlen         = sizeof(int),
 593                 .mode           = 0644,
 594                 .proc_handler   = &proc_dointvec,
 595         },
 596         {
 597                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 598                 .procname       = "printk_ratelimit",
 599                 .data           = &printk_ratelimit_jiffies,
 600                 .maxlen         = sizeof(int),
 601                 .mode           = 0644,
 602                 .proc_handler   = &proc_dointvec_jiffies,
 603                 .strategy       = &sysctl_jiffies,
 604         },
 605         {
 606                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 607                 .procname       = "printk_ratelimit_burst",
 608                 .data           = &printk_ratelimit_burst,
 609                 .maxlen         = sizeof(int),
 610                 .mode           = 0644,
 611                 .proc_handler   = &proc_dointvec,
 612         },
 613         {
 614                 .ctl_name       = KERN_NGROUPS_MAX,
 615                 .procname       = "ngroups_max",
 616                 .data           = &ngroups_max,
 617                 .maxlen         = sizeof (int),
 618                 .mode           = 0444,
 619                 .proc_handler   = &proc_dointvec,
 620         },
 621 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 622         {
 623                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
 624                 .procname       = "unknown_nmi_panic",
 625                 .data           = &unknown_nmi_panic,
 626                 .maxlen         = sizeof (int),
 627                 .mode           = 0644,
 628                 .proc_handler   = &proc_unknown_nmi_panic,
 629         },
 630 #endif
 631 #if defined(CONFIG_X86)
 632         {
 633                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 634                 .procname       = "bootloader_type",
 635                 .data           = &bootloader_type,
 636                 .maxlen         = sizeof (int),
 637                 .mode           = 0444,
 638                 .proc_handler   = &proc_dointvec,
 639         },
 640 #endif
 641         {
 642                 .ctl_name       = KERN_RANDOMIZE,
 643                 .procname       = "randomize_va_space",
 644                 .data           = &randomize_va_space,
 645                 .maxlen         = sizeof(int),
 646                 .mode           = 0644,
 647                 .proc_handler   = &proc_dointvec,
 648         },
 649 #if defined(CONFIG_ARCH_S390)
 650         {
 651                 .ctl_name       = KERN_SPIN_RETRY,
 652                 .procname       = "spin_retry",
 653                 .data           = &spin_retry,
 654                 .maxlen         = sizeof (int),
 655                 .mode           = 0644,
 656                 .proc_handler   = &proc_dointvec,
 657         },
 658 #endif
 659         { .ctl_name = 0 }
 660 };
 661
 662 /* Constants for minimum and maximum testing in vm_table.
 663    We use these as one-element integer vectors. */
 664 static int zero;
 665 static int one_hundred = 100;
 666
 667
 668 static ctl_table vm_table[] = {
 669         {
 670                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
 671                 .procname       = "overcommit_memory",
 672                 .data           = &sysctl_overcommit_memory,
 673                 .maxlen         = sizeof(sysctl_overcommit_memory),
 674                 .mode           = 0644,
 675                 .proc_handler   = &proc_dointvec,
 676         },
 677         {
 678                 .ctl_name       = VM_OVERCOMMIT_RATIO,
 679                 .procname       = "overcommit_ratio",
 680                 .data           = &sysctl_overcommit_ratio,
 681                 .maxlen         = sizeof(sysctl_overcommit_ratio),
 682                 .mode           = 0644,
 683                 .proc_handler   = &proc_dointvec,
 684         },
 685         {
 686                 .ctl_name       = VM_PAGE_CLUSTER,
 687                 .procname       = "page-cluster",
 688                 .data           = &page_cluster,
 689                 .maxlen         = sizeof(int),
 690                 .mode           = 0644,
 691                 .proc_handler   = &proc_dointvec,
 692         },
 693         {
 694                 .ctl_name       = VM_DIRTY_BACKGROUND,
 695                 .procname       = "dirty_background_ratio",
 696                 .data           = &dirty_background_ratio,
 697                 .maxlen         = sizeof(dirty_background_ratio),
 698                 .mode           = 0644,
 699                 .proc_handler   = &proc_dointvec_minmax,
 700                 .strategy       = &sysctl_intvec,
 701                 .extra1         = &zero,
 702                 .extra2         = &one_hundred,
 703         },
 704         {
 705                 .ctl_name       = VM_DIRTY_RATIO,
 706                 .procname       = "dirty_ratio",
 707                 .data           = &vm_dirty_ratio,
 708                 .maxlen         = sizeof(vm_dirty_ratio),
 709                 .mode           = 0644,
 710                 .proc_handler   = &proc_dointvec_minmax,
 711                 .strategy       = &sysctl_intvec,
 712                 .extra1         = &zero,
 713                 .extra2         = &one_hundred,
 714         },
 715         {
 716                 .ctl_name       = VM_DIRTY_WB_CS,
 717                 .procname       = "dirty_writeback_centisecs",
 718                 .data           = &dirty_writeback_centisecs,
 719                 .maxlen         = sizeof(dirty_writeback_centisecs),
 720                 .mode           = 0644,
 721                 .proc_handler   = &dirty_writeback_centisecs_handler,
 722         },
 723         {
 724                 .ctl_name       = VM_DIRTY_EXPIRE_CS,
 725                 .procname       = "dirty_expire_centisecs",
 726                 .data           = &dirty_expire_centisecs,
 727                 .maxlen         = sizeof(dirty_expire_centisecs),
 728                 .mode           = 0644,
 729                 .proc_handler   = &proc_dointvec,
 730         },
 731         {
 732                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
 733                 .procname       = "nr_pdflush_threads",
 734                 .data           = &nr_pdflush_threads,
 735                 .maxlen         = sizeof nr_pdflush_threads,
 736                 .mode           = 0444 /* read-only*/,
 737                 .proc_handler   = &proc_dointvec,
 738         },
 739         {
 740                 .ctl_name       = VM_SWAPPINESS,
 741                 .procname       = "swappiness",
 742                 .data           = &vm_swappiness,
 743                 .maxlen         = sizeof(vm_swappiness),
 744                 .mode           = 0644,
 745                 .proc_handler   = &proc_dointvec_minmax,
 746                 .strategy       = &sysctl_intvec,
 747                 .extra1         = &zero,
 748                 .extra2         = &one_hundred,
 749         },
 750 #ifdef CONFIG_HUGETLB_PAGE
 751          {
 752                 .ctl_name       = VM_HUGETLB_PAGES,
 753                 .procname       = "nr_hugepages",
 754                 .data           = &max_huge_pages,
 755                 .maxlen         = sizeof(unsigned long),
 756                 .mode           = 0644,
 757                 .proc_handler   = &hugetlb_sysctl_handler,
 758                 .extra1         = (void *)&hugetlb_zero,
 759                 .extra2         = (void *)&hugetlb_infinity,
 760          },
 761          {
 762                 .ctl_name       = VM_HUGETLB_GROUP,
 763                 .procname       = "hugetlb_shm_group",
 764                 .data           = &sysctl_hugetlb_shm_group,
 765                 .maxlen         = sizeof(gid_t),
 766                 .mode           = 0644,
 767                 .proc_handler   = &proc_dointvec,
 768          },
 769 #endif
 770         {
 771                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
 772                 .procname       = "lowmem_reserve_ratio",
 773                 .data           = &sysctl_lowmem_reserve_ratio,
 774                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
 775                 .mode           = 0644,
 776                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
 777                 .strategy       = &sysctl_intvec,
 778         },
 779         {
 780                 .ctl_name       = VM_MIN_FREE_KBYTES,
 781                 .procname       = "min_free_kbytes",
 782                 .data           = &min_free_kbytes,
 783                 .maxlen         = sizeof(min_free_kbytes),
 784                 .mode           = 0644,
 785                 .proc_handler   = &min_free_kbytes_sysctl_handler,
 786                 .strategy       = &sysctl_intvec,
 787                 .extra1         = &zero,
 788         },
 789 #ifdef CONFIG_MMU
 790         {
 791                 .ctl_name       = VM_MAX_MAP_COUNT,
 792                 .procname       = "max_map_count",
 793                 .data           = &sysctl_max_map_count,
 794                 .maxlen         = sizeof(sysctl_max_map_count),
 795                 .mode           = 0644,
 796                 .proc_handler   = &proc_dointvec
 797         },
 798 #endif
 799         {
 800                 .ctl_name       = VM_LAPTOP_MODE,
 801                 .procname       = "laptop_mode",
 802                 .data           = &laptop_mode,
 803                 .maxlen         = sizeof(laptop_mode),
 804                 .mode           = 0644,
 805                 .proc_handler   = &proc_dointvec,
 806                 .strategy       = &sysctl_intvec,
 807                 .extra1         = &zero,
 808         },
 809         {
 810                 .ctl_name       = VM_BLOCK_DUMP,
 811                 .procname       = "block_dump",
 812                 .data           = &block_dump,
 813                 .maxlen         = sizeof(block_dump),
 814                 .mode           = 0644,
 815                 .proc_handler   = &proc_dointvec,
 816                 .strategy       = &sysctl_intvec,
 817                 .extra1         = &zero,
 818         },
 819         {
 820                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
 821                 .procname       = "vfs_cache_pressure",
 822                 .data           = &sysctl_vfs_cache_pressure,
 823                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
 824                 .mode           = 0644,
 825                 .proc_handler   = &proc_dointvec,
 826                 .strategy       = &sysctl_intvec,
 827                 .extra1         = &zero,
 828         },
 829 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 830         {
 831                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
 832                 .procname       = "legacy_va_layout",
 833                 .data           = &sysctl_legacy_va_layout,
 834                 .maxlen         = sizeof(sysctl_legacy_va_layout),
 835                 .mode           = 0644,
 836                 .proc_handler   = &proc_dointvec,
 837                 .strategy       = &sysctl_intvec,
 838                 .extra1         = &zero,
 839         },
 840 #endif
 841 #ifdef CONFIG_SWAP
 842         {
 843                 .ctl_name       = VM_SWAP_TOKEN_TIMEOUT,
 844                 .procname       = "swap_token_timeout",
 845                 .data           = &swap_token_default_timeout,
 846                 .maxlen         = sizeof(swap_token_default_timeout),
 847                 .mode           = 0644,
 848                 .proc_handler   = &proc_dointvec_jiffies,
 849                 .strategy       = &sysctl_jiffies,
 850         },
 851 #endif
 852         { .ctl_name = 0 }
 853 };
 854
 855 static ctl_table proc_table[] = {
 856         { .ctl_name = 0 }
 857 };
 858
 859 static ctl_table fs_table[] = {
 860         {
 861                 .ctl_name       = FS_NRINODE,
 862                 .procname       = "inode-nr",
 863                 .data           = &inodes_stat,
 864                 .maxlen         = 2*sizeof(int),
 865                 .mode           = 0444,
 866                 .proc_handler   = &proc_dointvec,
 867         },
 868         {
 869                 .ctl_name       = FS_STATINODE,
 870                 .procname       = "inode-state",
 871                 .data           = &inodes_stat,
 872                 .maxlen         = 7*sizeof(int),
 873                 .mode           = 0444,
 874                 .proc_handler   = &proc_dointvec,
 875         },
 876         {
 877                 .ctl_name       = FS_NRFILE,
 878                 .procname       = "file-nr",
 879                 .data           = &files_stat,
 880                 .maxlen         = 3*sizeof(int),
 881                 .mode           = 0444,
 882                 .proc_handler   = &proc_dointvec,
 883         },
 884         {
 885                 .ctl_name       = FS_MAXFILE,
 886                 .procname       = "file-max",
 887                 .data           = &files_stat.max_files,
 888                 .maxlen         = sizeof(int),
 889                 .mode           = 0644,
 890                 .proc_handler   = &proc_dointvec,
 891         },
 892         {
 893                 .ctl_name       = FS_DENTRY,
 894                 .procname       = "dentry-state",
 895                 .data           = &dentry_stat,
 896                 .maxlen         = 6*sizeof(int),
 897                 .mode           = 0444,
 898                 .proc_handler   = &proc_dointvec,
 899         },
 900         {
 901                 .ctl_name       = FS_OVERFLOWUID,
 902                 .procname       = "overflowuid",
 903                 .data           = &fs_overflowuid,
 904                 .maxlen         = sizeof(int),
 905                 .mode           = 0644,
 906                 .proc_handler   = &proc_dointvec_minmax,
 907                 .strategy       = &sysctl_intvec,
 908                 .extra1         = &minolduid,
 909                 .extra2         = &maxolduid,
 910         },
 911         {
 912                 .ctl_name       = FS_OVERFLOWGID,
 913                 .procname       = "overflowgid",
 914                 .data           = &fs_overflowgid,
 915                 .maxlen         = sizeof(int),
 916                 .mode           = 0644,
 917                 .proc_handler   = &proc_dointvec_minmax,
 918                 .strategy       = &sysctl_intvec,
 919                 .extra1         = &minolduid,
 920                 .extra2         = &maxolduid,
 921         },
 922         {
 923                 .ctl_name       = FS_LEASES,
 924                 .procname       = "leases-enable",
 925                 .data           = &leases_enable,
 926                 .maxlen         = sizeof(int),
 927                 .mode           = 0644,
 928                 .proc_handler   = &proc_dointvec,
 929         },
 930 #ifdef CONFIG_DNOTIFY
 931         {
 932                 .ctl_name       = FS_DIR_NOTIFY,
 933                 .procname       = "dir-notify-enable",
 934                 .data           = &dir_notify_enable,
 935                 .maxlen         = sizeof(int),
 936                 .mode           = 0644,
 937                 .proc_handler   = &proc_dointvec,
 938         },
 939 #endif
 940 #ifdef CONFIG_MMU
 941         {
 942                 .ctl_name       = FS_LEASE_TIME,
 943                 .procname       = "lease-break-time",
 944                 .data           = &lease_break_time,
 945                 .maxlen         = sizeof(int),
 946                 .mode           = 0644,
 947                 .proc_handler   = &proc_dointvec,
 948         },
 949         {
 950                 .ctl_name       = FS_AIO_NR,
 951                 .procname       = "aio-nr",
 952                 .data           = &aio_nr,
 953                 .maxlen         = sizeof(aio_nr),
 954                 .mode           = 0444,
 955                 .proc_handler   = &proc_doulongvec_minmax,
 956         },
 957         {
 958                 .ctl_name       = FS_AIO_MAX_NR,
 959                 .procname       = "aio-max-nr",
 960                 .data           = &aio_max_nr,
 961                 .maxlen         = sizeof(aio_max_nr),
 962                 .mode           = 0644,
 963                 .proc_handler   = &proc_doulongvec_minmax,
 964         },
 965 #ifdef CONFIG_INOTIFY
 966         {
 967                 .ctl_name       = FS_INOTIFY,
 968                 .procname       = "inotify",
 969                 .mode           = 0555,
 970                 .child          = inotify_table,
 971         },
 972 #endif
 973 #endif
 974         {
 975                 .ctl_name       = KERN_SETUID_DUMPABLE,
 976                 .procname       = "suid_dumpable",
 977                 .data           = &suid_dumpable,
 978                 .maxlen         = sizeof(int),
 979                 .mode           = 0644,
 980                 .proc_handler   = &proc_dointvec,
 981         },
 982         { .ctl_name = 0 }
 983 };
 984
 985 static ctl_table debug_table[] = {
 986         { .ctl_name = 0 }
 987 };
 988
 989 static ctl_table dev_table[] = {
 990         { .ctl_name = 0 }
 991 };
 992
 993 extern void init_irq_proc (void);
 994
 995 static DEFINE_SPINLOCK(sysctl_lock);
 996
 997 /* called under sysctl_lock */
 998 static int use_table(struct ctl_table_header *p)
 999 {
1000         if (unlikely(p->unregistering))
1001                 return 0;
1002         p->used++;
1003         return 1;
1004 }
1005
1006 /* called under sysctl_lock */
1007 static void unuse_table(struct ctl_table_header *p)
1008 {
1009         if (!--p->used)
1010                 if (unlikely(p->unregistering))
1011                         complete(p->unregistering);
1012 }
1013
1014 /* called under sysctl_lock, will reacquire if has to wait */
1015 static void start_unregistering(struct ctl_table_header *p)
1016 {
1017         /*
1018          * if p->used is 0, nobody will ever touch that entry again;
1019          * we'll eliminate all paths to it before dropping sysctl_lock
1020          */
1021         if (unlikely(p->used)) {
1022                 struct completion wait;
1023                 init_completion(&wait);
1024                 p->unregistering = &wait;
1025                 spin_unlock(&sysctl_lock);
1026                 wait_for_completion(&wait);
1027                 spin_lock(&sysctl_lock);
1028         }
1029         /*
1030          * do not remove from the list until nobody holds it; walking the
1031          * list in do_sysctl() relies on that.
1032          */
1033         list_del_init(&p->ctl_entry);
1034 }
1035
1036 void __init sysctl_init(void)
1037 {
1038 #ifdef CONFIG_PROC_FS
1039         register_proc_table(root_table, proc_sys_root, &root_table_header);
1040         init_irq_proc();
1041 #endif
1042 }
1043
1044 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1045                void __user *newval, size_t newlen)
1046 {
1047         struct list_head *tmp;
1048         int error = -ENOTDIR;
1049
1050         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1051                 return -ENOTDIR;
1052         if (oldval) {
1053                 int old_len;
1054                 if (!oldlenp || get_user(old_len, oldlenp))
1055                         return -EFAULT;
1056         }
1057         spin_lock(&sysctl_lock);
1058         tmp = &root_table_header.ctl_entry;
1059         do {
1060                 struct ctl_table_header *head =
1061                         list_entry(tmp, struct ctl_table_header, ctl_entry);
1062                 void *context = NULL;
1063
1064                 if (!use_table(head))
1065                         continue;
1066
1067                 spin_unlock(&sysctl_lock);
1068
1069                 error = parse_table(name, nlen, oldval, oldlenp,
1070                                         newval, newlen, head->ctl_table,
1071                                         &context);
1072                 kfree(context);
1073
1074                 spin_lock(&sysctl_lock);
1075                 unuse_table(head);
1076                 if (error != -ENOTDIR)
1077                         break;
1078         } while ((tmp = tmp->next) != &root_table_header.ctl_entry);
1079         spin_unlock(&sysctl_lock);
1080         return error;
1081 }
1082
1083 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1084 {
1085         struct __sysctl_args tmp;
1086         int error;
1087
1088         if (copy_from_user(&tmp, args, sizeof(tmp)))
1089                 return -EFAULT;
1090
1091         lock_kernel();
1092         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1093                           tmp.newval, tmp.newlen);
1094         unlock_kernel();
1095         return error;
1096 }
1097
1098 /*
1099  * ctl_perm does NOT grant the superuser all rights automatically, because
1100  * some sysctl variables are readonly even to root.
1101  */
1102
1103 static int test_perm(int mode, int op)
1104 {
1105         if (!current->euid)
1106                 mode >>= 6;
1107         else if (in_egroup_p(0))
1108                 mode >>= 3;
1109         if ((mode & op & 0007) == op)
1110                 return 0;
1111         return -EACCES;
1112 }
1113
1114 static inline int ctl_perm(ctl_table *table, int op)
1115 {
1116         int error;
1117         error = security_sysctl(table, op);
1118         if (error)
1119                 return error;
1120         return test_perm(table->mode, op);
1121 }
1122
1123 static int parse_table(int __user *name, int nlen,
1124                        void __user *oldval, size_t __user *oldlenp,
1125                        void __user *newval, size_t newlen,
1126                        ctl_table *table, void **context)
1127 {
1128         int n;
1129 repeat:
1130         if (!nlen)
1131                 return -ENOTDIR;
1132         if (get_user(n, name))
1133                 return -EFAULT;
1134         for ( ; table->ctl_name; table++) {
1135                 if (n == table->ctl_name || table->ctl_name == CTL_ANY) {
1136                         int error;
1137                         if (table->child) {
1138                                 if (ctl_perm(table, 001))
1139                                         return -EPERM;
1140                                 if (table->strategy) {
1141                                         error = table->strategy(
1142                                                 table, name, nlen,
1143                                                 oldval, oldlenp,
1144                                                 newval, newlen, context);
1145                                         if (error)
1146                                                 return error;
1147                                 }
1148                                 name++;
1149                                 nlen--;
1150                                 table = table->child;
1151                                 goto repeat;
1152                         }
1153                         error = do_sysctl_strategy(table, name, nlen,
1154                                                    oldval, oldlenp,
1155                                                    newval, newlen, context);
1156                         return error;
1157                 }
1158         }
1159         return -ENOTDIR;
1160 }
1161
1162 /* Perform the actual read/write of a sysctl table entry. */
1163 int do_sysctl_strategy (ctl_table *table,
1164                         int __user *name, int nlen,
1165                         void __user *oldval, size_t __user *oldlenp,
1166                         void __user *newval, size_t newlen, void **context)
1167 {
1168         int op = 0, rc;
1169         size_t len;
1170
1171         if (oldval)
1172                 op |= 004;
1173         if (newval)
1174                 op |= 002;
1175         if (ctl_perm(table, op))
1176                 return -EPERM;
1177
1178         if (table->strategy) {
1179                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1180                                      newval, newlen, context);
1181                 if (rc < 0)
1182                         return rc;
1183                 if (rc > 0)
1184                         return 0;
1185         }
1186
1187         /* If there is no strategy routine, or if the strategy returns
1188          * zero, proceed with automatic r/w */
1189         if (table->data && table->maxlen) {
1190                 if (oldval && oldlenp) {
1191                         if (get_user(len, oldlenp))
1192                                 return -EFAULT;
1193                         if (len) {
1194                                 if (len > table->maxlen)
1195                                         len = table->maxlen;
1196                                 if(copy_to_user(oldval, table->data, len))
1197                                         return -EFAULT;
1198                                 if(put_user(len, oldlenp))
1199                                         return -EFAULT;
1200                         }
1201                 }
1202                 if (newval && newlen) {
1203                         len = newlen;
1204                         if (len > table->maxlen)
1205                                 len = table->maxlen;
1206                         if(copy_from_user(table->data, newval, len))
1207                                 return -EFAULT;
1208                 }
1209         }
1210         return 0;
1211 }
1212
1213 /**
1214  * register_sysctl_table - register a sysctl hierarchy
1215  * @table: the top-level table structure
1216  * @insert_at_head: whether the entry should be inserted in front or at the end
1217  *
1218  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1219  * array. An entry with a ctl_name of 0 terminates the table.
1220  *
1221  * The members of the &ctl_table structure are used as follows:
1222  *
1223  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1224  *            must be unique within that level of sysctl
1225  *
1226  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1227  *            enter a sysctl file
1228  *
1229  * data - a pointer to data for use by proc_handler
1230  *
1231  * maxlen - the maximum size in bytes of the data
1232  *
1233  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1234  *
1235  * child - a pointer to the child sysctl table if this entry is a directory, or
1236  *         %NULL.
1237  *
1238  * proc_handler - the text handler routine (described below)
1239  *
1240  * strategy - the strategy routine (described below)
1241  *
1242  * de - for internal use by the sysctl routines
1243  *
1244  * extra1, extra2 - extra pointers usable by the proc handler routines
1245  *
1246  * Leaf nodes in the sysctl tree will be represented by a single file
1247  * under /proc; non-leaf nodes will be represented by directories.
1248  *
1249  * sysctl(2) can automatically manage read and write requests through
1250  * the sysctl table.  The data and maxlen fields of the ctl_table
1251  * struct enable minimal validation of the values being written to be
1252  * performed, and the mode field allows minimal authentication.
1253  *
1254  * More sophisticated management can be enabled by the provision of a
1255  * strategy routine with the table entry.  This will be called before
1256  * any automatic read or write of the data is performed.
1257  *
1258  * The strategy routine may return
1259  *
1260  * < 0 - Error occurred (error is passed to user process)
1261  *
1262  * 0   - OK - proceed with automatic read or write.
1263  *
1264  * > 0 - OK - read or write has been done by the strategy routine, so
1265  *       return immediately.
1266  *
1267  * There must be a proc_handler routine for any terminal nodes
1268  * mirrored under /proc/sys (non-terminals are handled by a built-in
1269  * directory handler).  Several default handlers are available to
1270  * cover common cases -
1271  *
1272  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1273  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1274  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1275  *
1276  * It is the handler's job to read the input buffer from user memory
1277  * and process it. The handler should return 0 on success.
1278  *
1279  * This routine returns %NULL on a failure to register, and a pointer
1280  * to the table header on success.
1281  */
1282 struct ctl_table_header *register_sysctl_table(ctl_table * table,
1283                                                int insert_at_head)
1284 {
1285         struct ctl_table_header *tmp;
1286         tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1287         if (!tmp)
1288                 return NULL;
1289         tmp->ctl_table = table;
1290         INIT_LIST_HEAD(&tmp->ctl_entry);
1291         tmp->used = 0;
1292         tmp->unregistering = NULL;
1293         spin_lock(&sysctl_lock);
1294         if (insert_at_head)
1295                 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
1296         else
1297                 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1298         spin_unlock(&sysctl_lock);
1299 #ifdef CONFIG_PROC_FS
1300         register_proc_table(table, proc_sys_root, tmp);
1301 #endif
1302         return tmp;
1303 }
1304
1305 /**
1306  * unregister_sysctl_table - unregister a sysctl table hierarchy
1307  * @header: the header returned from register_sysctl_table
1308  *
1309  * Unregisters the sysctl table and all children. proc entries may not
1310  * actually be removed until they are no longer used by anyone.
1311  */
1312 void unregister_sysctl_table(struct ctl_table_header * header)
1313 {
1314         might_sleep();
1315         spin_lock(&sysctl_lock);
1316         start_unregistering(header);
1317 #ifdef CONFIG_PROC_FS
1318         unregister_proc_table(header->ctl_table, proc_sys_root);
1319 #endif
1320         spin_unlock(&sysctl_lock);
1321         kfree(header);
1322 }
1323
1324 /*
1325  * /proc/sys support
1326  */
1327
1328 #ifdef CONFIG_PROC_FS
1329
1330 /* Scan the sysctl entries in table and add them all into /proc */
1331 static void register_proc_table(ctl_table * table, struct proc_dir_entry *root, void *set)
1332 {
1333         struct proc_dir_entry *de;
1334         int len;
1335         mode_t mode;
1336
1337         for (; table->ctl_name; table++) {
1338                 /* Can't do anything without a proc name. */
1339                 if (!table->procname)
1340                         continue;
1341                 /* Maybe we can't do anything with it... */
1342                 if (!table->proc_handler && !table->child) {
1343                         printk(KERN_WARNING "SYSCTL: Can't register %s\n",
1344                                 table->procname);
1345                         continue;
1346                 }
1347
1348                 len = strlen(table->procname);
1349                 mode = table->mode;
1350
1351                 de = NULL;
1352                 if (table->proc_handler)
1353                         mode |= S_IFREG;
1354                 else {
1355                         mode |= S_IFDIR;
1356                         for (de = root->subdir; de; de = de->next) {
1357                                 if (proc_match(len, table->procname, de))
1358                                         break;
1359                         }
1360                         /* If the subdir exists already, de is non-NULL */
1361                 }
1362
1363                 if (!de) {
1364                         de = create_proc_entry(table->procname, mode, root);
1365                         if (!de)
1366                                 continue;
1367                         de->set = set;
1368                         de->data = (void *) table;
1369                         if (table->proc_handler)
1370                                 de->proc_fops = &proc_sys_file_operations;
1371                 }
1372                 table->de = de;
1373                 if (de->mode & S_IFDIR)
1374                         register_proc_table(table->child, de, set);
1375         }
1376 }
1377
1378 /*
1379  * Unregister a /proc sysctl table and any subdirectories.
1380  */
1381 static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
1382 {
1383         struct proc_dir_entry *de;
1384         for (; table->ctl_name; table++) {
1385                 if (!(de = table->de))
1386                         continue;
1387                 if (de->mode & S_IFDIR) {
1388                         if (!table->child) {
1389                                 printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
1390                                 continue;
1391                         }
1392                         unregister_proc_table(table->child, de);
1393
1394                         /* Don't unregister directories which still have entries.. */
1395                         if (de->subdir)
1396                                 continue;
1397                 }
1398
1399                 /*
1400                  * In any case, mark the entry as goner; we'll keep it
1401                  * around if it's busy, but we'll know to do nothing with
1402                  * its fields.  We are under sysctl_lock here.
1403                  */
1404                 de->data = NULL;
1405
1406                 /* Don't unregister proc entries that are still being used.. */
1407                 if (atomic_read(&de->count))
1408                         continue;
1409
1410                 table->de = NULL;
1411                 remove_proc_entry(table->procname, root);
1412         }
1413 }
1414
1415 static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
1416                           size_t count, loff_t *ppos)
1417 {
1418         int op;
1419         struct proc_dir_entry *de = PDE(file->f_dentry->d_inode);
1420         struct ctl_table *table;
1421         size_t res;
1422         ssize_t error = -ENOTDIR;
1423
1424         spin_lock(&sysctl_lock);
1425         if (de && de->data && use_table(de->set)) {
1426                 /*
1427                  * at that point we know that sysctl was not unregistered
1428                  * and won't be until we finish
1429                  */
1430                 spin_unlock(&sysctl_lock);
1431                 table = (struct ctl_table *) de->data;
1432                 if (!table || !table->proc_handler)
1433                         goto out;
1434                 error = -EPERM;
1435                 op = (write ? 002 : 004);
1436                 if (ctl_perm(table, op))
1437                         goto out;
1438
1439                 /* careful: calling conventions are nasty here */
1440                 res = count;
1441                 error = (*table->proc_handler)(table, write, file,
1442                                                 buf, &res, ppos);
1443                 if (!error)
1444                         error = res;
1445         out:
1446                 spin_lock(&sysctl_lock);
1447                 unuse_table(de->set);
1448         }
1449         spin_unlock(&sysctl_lock);
1450         return error;
1451 }
1452
1453 static int proc_opensys(struct inode *inode, struct file *file)
1454 {
1455         if (file->f_mode & FMODE_WRITE) {
1456                 /*
1457                  * sysctl entries that are not writable,
1458                  * are _NOT_ writable, capabilities or not.
1459                  */
1460                 if (!(inode->i_mode & S_IWUSR))
1461                         return -EPERM;
1462         }
1463
1464         return 0;
1465 }
1466
1467 static ssize_t proc_readsys(struct file * file, char __user * buf,
1468                             size_t count, loff_t *ppos)
1469 {
1470         return do_rw_proc(0, file, buf, count, ppos);
1471 }
1472
1473 static ssize_t proc_writesys(struct file * file, const char __user * buf,
1474                              size_t count, loff_t *ppos)
1475 {
1476         return do_rw_proc(1, file, (char __user *) buf, count, ppos);
1477 }
1478
1479 /**
1480  * proc_dostring - read a string sysctl
1481  * @table: the sysctl table
1482  * @write: %TRUE if this is a write to the sysctl file
1483  * @filp: the file structure
1484  * @buffer: the user buffer
1485  * @lenp: the size of the user buffer
1486  * @ppos: file position
1487  *
1488  * Reads/writes a string from/to the user buffer. If the kernel
1489  * buffer provided is not large enough to hold the string, the
1490  * string is truncated. The copied string is %NULL-terminated.
1491  * If the string is being read by the user process, it is copied
1492  * and a newline '\n' is added. It is truncated if the buffer is
1493  * not large enough.
1494  *
1495  * Returns 0 on success.
1496  */
1497 int proc_dostring(ctl_table *table, int write, struct file *filp,
1498                   void __user *buffer, size_t *lenp, loff_t *ppos)
1499 {
1500         size_t len;
1501         char __user *p;
1502         char c;
1503
1504         if (!table->data || !table->maxlen || !*lenp ||
1505             (*ppos && !write)) {
1506                 *lenp = 0;
1507                 return 0;
1508         }
1509
1510         if (write) {
1511                 len = 0;
1512                 p = buffer;
1513                 while (len < *lenp) {
1514                         if (get_user(c, p++))
1515                                 return -EFAULT;
1516                         if (c == 0 || c == '\n')
1517                                 break;
1518                         len++;
1519                 }
1520                 if (len >= table->maxlen)
1521                         len = table->maxlen-1;
1522                 if(copy_from_user(table->data, buffer, len))
1523                         return -EFAULT;
1524                 ((char *) table->data)[len] = 0;
1525                 *ppos += *lenp;
1526         } else {
1527                 len = strlen(table->data);
1528                 if (len > table->maxlen)
1529                         len = table->maxlen;
1530                 if (len > *lenp)
1531                         len = *lenp;
1532                 if (len)
1533                         if(copy_to_user(buffer, table->data, len))
1534                                 return -EFAULT;
1535                 if (len < *lenp) {
1536                         if(put_user('\n', ((char __user *) buffer) + len))
1537                                 return -EFAULT;
1538                         len++;
1539                 }
1540                 *lenp = len;
1541                 *ppos += len;
1542         }
1543         return 0;
1544 }
1545
1546 /*
1547  *      Special case of dostring for the UTS structure. This has locks
1548  *      to observe. Should this be in kernel/sys.c ????
1549  */
1550
1551 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
1552                   void __user *buffer, size_t *lenp, loff_t *ppos)
1553 {
1554         int r;
1555
1556         if (!write) {
1557                 down_read(&uts_sem);
1558                 r=proc_dostring(table,0,filp,buffer,lenp, ppos);
1559                 up_read(&uts_sem);
1560         } else {
1561                 down_write(&uts_sem);
1562                 r=proc_dostring(table,1,filp,buffer,lenp, ppos);
1563                 up_write(&uts_sem);
1564         }
1565         return r;
1566 }
1567
1568 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1569                                  int *valp,
1570                                  int write, void *data)
1571 {
1572         if (write) {
1573                 *valp = *negp ? -*lvalp : *lvalp;
1574         } else {
1575                 int val = *valp;
1576                 if (val < 0) {
1577                         *negp = -1;
1578                         *lvalp = (unsigned long)-val;
1579                 } else {
1580                         *negp = 0;
1581                         *lvalp = (unsigned long)val;
1582                 }
1583         }
1584         return 0;
1585 }
1586
1587 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1588                   void __user *buffer, size_t *lenp, loff_t *ppos,
1589                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1590                               int write, void *data),
1591                   void *data)
1592 {
1593 #define TMPBUFLEN 21
1594         int *i, vleft, first=1, neg, val;
1595         unsigned long lval;
1596         size_t left, len;
1597
1598         char buf[TMPBUFLEN], *p;
1599         char __user *s = buffer;
1600
1601         if (!table->data || !table->maxlen || !*lenp ||
1602             (*ppos && !write)) {
1603                 *lenp = 0;
1604                 return 0;
1605         }
1606
1607         i = (int *) table->data;
1608         vleft = table->maxlen / sizeof(*i);
1609         left = *lenp;
1610
1611         if (!conv)
1612                 conv = do_proc_dointvec_conv;
1613
1614         for (; left && vleft--; i++, first=0) {
1615                 if (write) {
1616                         while (left) {
1617                                 char c;
1618                                 if (get_user(c, s))
1619                                         return -EFAULT;
1620                                 if (!isspace(c))
1621                                         break;
1622                                 left--;
1623                                 s++;
1624                         }
1625                         if (!left)
1626                                 break;
1627                         neg = 0;
1628                         len = left;
1629                         if (len > sizeof(buf) - 1)
1630                                 len = sizeof(buf) - 1;
1631                         if (copy_from_user(buf, s, len))
1632                                 return -EFAULT;
1633                         buf[len] = 0;
1634                         p = buf;
1635                         if (*p == '-' && left > 1) {
1636                                 neg = 1;
1637                                 left--, p++;
1638                         }
1639                         if (*p < '0' || *p > '9')
1640                                 break;
1641
1642                         lval = simple_strtoul(p, &p, 0);
1643
1644                         len = p-buf;
1645                         if ((len < left) && *p && !isspace(*p))
1646                                 break;
1647                         if (neg)
1648                                 val = -val;
1649                         s += len;
1650                         left -= len;
1651
1652                         if (conv(&neg, &lval, i, 1, data))
1653                                 break;
1654                 } else {
1655                         p = buf;
1656                         if (!first)
1657                                 *p++ = '\t';
1658
1659                         if (conv(&neg, &lval, i, 0, data))
1660                                 break;
1661
1662                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
1663                         len = strlen(buf);
1664                         if (len > left)
1665                                 len = left;
1666                         if(copy_to_user(s, buf, len))
1667                                 return -EFAULT;
1668                         left -= len;
1669                         s += len;
1670                 }
1671         }
1672
1673         if (!write && !first && left) {
1674                 if(put_user('\n', s))
1675                         return -EFAULT;
1676                 left--, s++;
1677         }
1678         if (write) {
1679                 while (left) {
1680                         char c;
1681                         if (get_user(c, s++))
1682                                 return -EFAULT;
1683                         if (!isspace(c))
1684                                 break;
1685                         left--;
1686                 }
1687         }
1688         if (write && first)
1689                 return -EINVAL;
1690         *lenp -= left;
1691         *ppos += *lenp;
1692         return 0;
1693 #undef TMPBUFLEN
1694 }
1695
1696 /**
1697  * proc_dointvec - read a vector of integers
1698  * @table: the sysctl table
1699  * @write: %TRUE if this is a write to the sysctl file
1700  * @filp: the file structure
1701  * @buffer: the user buffer
1702  * @lenp: the size of the user buffer
1703  * @ppos: file position
1704  *
1705  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1706  * values from/to the user buffer, treated as an ASCII string.
1707  *
1708  * Returns 0 on success.
1709  */
1710 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1711                      void __user *buffer, size_t *lenp, loff_t *ppos)
1712 {
1713     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1714                             NULL,NULL);
1715 }
1716
1717 #define OP_SET  0
1718 #define OP_AND  1
1719 #define OP_OR   2
1720 #define OP_MAX  3
1721 #define OP_MIN  4
1722
1723 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1724                                       int *valp,
1725                                       int write, void *data)
1726 {
1727         int op = *(int *)data;
1728         if (write) {
1729                 int val = *negp ? -*lvalp : *lvalp;
1730                 switch(op) {
1731                 case OP_SET:    *valp = val; break;
1732                 case OP_AND:    *valp &= val; break;
1733                 case OP_OR:     *valp |= val; break;
1734                 case OP_MAX:    if(*valp < val)
1735                                         *valp = val;
1736                                 break;
1737                 case OP_MIN:    if(*valp > val)
1738                                 *valp = val;
1739                                 break;
1740                 }
1741         } else {
1742                 int val = *valp;
1743                 if (val < 0) {
1744                         *negp = -1;
1745                         *lvalp = (unsigned long)-val;
1746                 } else {
1747                         *negp = 0;
1748                         *lvalp = (unsigned long)val;
1749                 }
1750         }
1751         return 0;
1752 }
1753
1754 /*
1755  *      init may raise the set.
1756  */
1757
1758 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1759                         void __user *buffer, size_t *lenp, loff_t *ppos)
1760 {
1761         int op;
1762
1763         if (!capable(CAP_SYS_MODULE)) {
1764                 return -EPERM;
1765         }
1766
1767         op = (current->pid == 1) ? OP_SET : OP_AND;
1768         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1769                                 do_proc_dointvec_bset_conv,&op);
1770 }
1771
1772 struct do_proc_dointvec_minmax_conv_param {
1773         int *min;
1774         int *max;
1775 };
1776
1777 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1778                                         int *valp,
1779                                         int write, void *data)
1780 {
1781         struct do_proc_dointvec_minmax_conv_param *param = data;
1782         if (write) {
1783                 int val = *negp ? -*lvalp : *lvalp;
1784                 if ((param->min && *param->min > val) ||
1785                     (param->max && *param->max < val))
1786                         return -EINVAL;
1787                 *valp = val;
1788         } else {
1789                 int val = *valp;
1790                 if (val < 0) {
1791                         *negp = -1;
1792                         *lvalp = (unsigned long)-val;
1793                 } else {
1794                         *negp = 0;
1795                         *lvalp = (unsigned long)val;
1796                 }
1797         }
1798         return 0;
1799 }
1800
1801 /**
1802  * proc_dointvec_minmax - read a vector of integers with min/max values
1803  * @table: the sysctl table
1804  * @write: %TRUE if this is a write to the sysctl file
1805  * @filp: the file structure
1806  * @buffer: the user buffer
1807  * @lenp: the size of the user buffer
1808  * @ppos: file position
1809  *
1810  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1811  * values from/to the user buffer, treated as an ASCII string.
1812  *
1813  * This routine will ensure the values are within the range specified by
1814  * table->extra1 (min) and table->extra2 (max).
1815  *
1816  * Returns 0 on success.
1817  */
1818 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1819                   void __user *buffer, size_t *lenp, loff_t *ppos)
1820 {
1821         struct do_proc_dointvec_minmax_conv_param param = {
1822                 .min = (int *) table->extra1,
1823                 .max = (int *) table->extra2,
1824         };
1825         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1826                                 do_proc_dointvec_minmax_conv, &param);
1827 }
1828
1829 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1830                                      struct file *filp,
1831                                      void __user *buffer,
1832                                      size_t *lenp, loff_t *ppos,
1833                                      unsigned long convmul,
1834                                      unsigned long convdiv)
1835 {
1836 #define TMPBUFLEN 21
1837         unsigned long *i, *min, *max, val;
1838         int vleft, first=1, neg;
1839         size_t len, left;
1840         char buf[TMPBUFLEN], *p;
1841         char __user *s = buffer;
1842
1843         if (!table->data || !table->maxlen || !*lenp ||
1844             (*ppos && !write)) {
1845                 *lenp = 0;
1846                 return 0;
1847         }
1848
1849         i = (unsigned long *) table->data;
1850         min = (unsigned long *) table->extra1;
1851         max = (unsigned long *) table->extra2;
1852         vleft = table->maxlen / sizeof(unsigned long);
1853         left = *lenp;
1854
1855         for (; left && vleft--; i++, min++, max++, first=0) {
1856                 if (write) {
1857                         while (left) {
1858                                 char c;
1859                                 if (get_user(c, s))
1860                                         return -EFAULT;
1861                                 if (!isspace(c))
1862                                         break;
1863                                 left--;
1864                                 s++;
1865                         }
1866                         if (!left)
1867                                 break;
1868                         neg = 0;
1869                         len = left;
1870                         if (len > TMPBUFLEN-1)
1871                                 len = TMPBUFLEN-1;
1872                         if (copy_from_user(buf, s, len))
1873                                 return -EFAULT;
1874                         buf[len] = 0;
1875                         p = buf;
1876                         if (*p == '-' && left > 1) {
1877                                 neg = 1;
1878                                 left--, p++;
1879                         }
1880                         if (*p < '0' || *p > '9')
1881                                 break;
1882                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1883                         len = p-buf;
1884                         if ((len < left) && *p && !isspace(*p))
1885                                 break;
1886                         if (neg)
1887                                 val = -val;
1888                         s += len;
1889                         left -= len;
1890
1891                         if(neg)
1892                                 continue;
1893                         if ((min && val < *min) || (max && val > *max))
1894                                 continue;
1895                         *i = val;
1896                 } else {
1897                         p = buf;
1898                         if (!first)
1899                                 *p++ = '\t';
1900                         sprintf(p, "%lu", convdiv * (*i) / convmul);
1901                         len = strlen(buf);
1902                         if (len > left)
1903                                 len = left;
1904                         if(copy_to_user(s, buf, len))
1905                                 return -EFAULT;
1906                         left -= len;
1907                         s += len;
1908                 }
1909         }
1910
1911         if (!write && !first && left) {
1912                 if(put_user('\n', s))
1913                         return -EFAULT;
1914                 left--, s++;
1915         }
1916         if (write) {
1917                 while (left) {
1918                         char c;
1919                         if (get_user(c, s++))
1920                                 return -EFAULT;
1921                         if (!isspace(c))
1922                                 break;
1923                         left--;
1924                 }
1925         }
1926         if (write && first)
1927                 return -EINVAL;
1928         *lenp -= left;
1929         *ppos += *lenp;
1930         return 0;
1931 #undef TMPBUFLEN
1932 }
1933
1934 /**
1935  * proc_doulongvec_minmax - read a vector of long integers with min/max values
1936  * @table: the sysctl table
1937  * @write: %TRUE if this is a write to the sysctl file
1938  * @filp: the file structure
1939  * @buffer: the user buffer
1940  * @lenp: the size of the user buffer
1941  * @ppos: file position
1942  *
1943  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1944  * values from/to the user buffer, treated as an ASCII string.
1945  *
1946  * This routine will ensure the values are within the range specified by
1947  * table->extra1 (min) and table->extra2 (max).
1948  *
1949  * Returns 0 on success.
1950  */
1951 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
1952                            void __user *buffer, size_t *lenp, loff_t *ppos)
1953 {
1954     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
1955 }
1956
1957 /**
1958  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
1959  * @table: the sysctl table
1960  * @write: %TRUE if this is a write to the sysctl file
1961  * @filp: the file structure
1962  * @buffer: the user buffer
1963  * @lenp: the size of the user buffer
1964  * @ppos: file position
1965  *
1966  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1967  * values from/to the user buffer, treated as an ASCII string. The values
1968  * are treated as milliseconds, and converted to jiffies when they are stored.
1969  *
1970  * This routine will ensure the values are within the range specified by
1971  * table->extra1 (min) and table->extra2 (max).
1972  *
1973  * Returns 0 on success.
1974  */
1975 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
1976                                       struct file *filp,
1977                                       void __user *buffer,
1978                                       size_t *lenp, loff_t *ppos)
1979 {
1980     return do_proc_doulongvec_minmax(table, write, filp, buffer,
1981                                      lenp, ppos, HZ, 1000l);
1982 }
1983
1984
1985 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
1986                                          int *valp,
1987                                          int write, void *data)
1988 {
1989         if (write) {
1990                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
1991         } else {
1992                 int val = *valp;
1993                 unsigned long lval;
1994                 if (val < 0) {
1995                         *negp = -1;
1996                         lval = (unsigned long)-val;
1997                 } else {
1998                         *negp = 0;
1999                         lval = (unsigned long)val;
2000                 }
2001                 *lvalp = lval / HZ;
2002         }
2003         return 0;
2004 }
2005
2006 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2007                                                 int *valp,
2008                                                 int write, void *data)
2009 {
2010         if (write) {
2011                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2012         } else {
2013                 int val = *valp;
2014                 unsigned long lval;
2015                 if (val < 0) {
2016                         *negp = -1;
2017                         lval = (unsigned long)-val;
2018                 } else {
2019                         *negp = 0;
2020                         lval = (unsigned long)val;
2021                 }
2022                 *lvalp = jiffies_to_clock_t(lval);
2023         }
2024         return 0;
2025 }
2026
2027 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2028                                             int *valp,
2029                                             int write, void *data)
2030 {
2031         if (write) {
2032                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2033         } else {
2034                 int val = *valp;
2035                 unsigned long lval;
2036                 if (val < 0) {
2037                         *negp = -1;
2038                         lval = (unsigned long)-val;
2039                 } else {
2040                         *negp = 0;
2041                         lval = (unsigned long)val;
2042                 }
2043                 *lvalp = jiffies_to_msecs(lval);
2044         }
2045         return 0;
2046 }
2047
2048 /**
2049  * proc_dointvec_jiffies - read a vector of integers as seconds
2050  * @table: the sysctl table
2051  * @write: %TRUE if this is a write to the sysctl file
2052  * @filp: the file structure
2053  * @buffer: the user buffer
2054  * @lenp: the size of the user buffer
2055  * @ppos: file position
2056  *
2057  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2058  * values from/to the user buffer, treated as an ASCII string.
2059  * The values read are assumed to be in seconds, and are converted into
2060  * jiffies.
2061  *
2062  * Returns 0 on success.
2063  */
2064 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2065                           void __user *buffer, size_t *lenp, loff_t *ppos)
2066 {
2067     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2068                             do_proc_dointvec_jiffies_conv,NULL);
2069 }
2070
2071 /**
2072  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2073  * @table: the sysctl table
2074  * @write: %TRUE if this is a write to the sysctl file
2075  * @filp: the file structure
2076  * @buffer: the user buffer
2077  * @lenp: the size of the user buffer
2078  * @ppos: pointer to the file position
2079  *
2080  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2081  * values from/to the user buffer, treated as an ASCII string.
2082  * The values read are assumed to be in 1/USER_HZ seconds, and
2083  * are converted into jiffies.
2084  *
2085  * Returns 0 on success.
2086  */
2087 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2088                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2089 {
2090     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2091                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2092 }
2093
2094 /**
2095  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2096  * @table: the sysctl table
2097  * @write: %TRUE if this is a write to the sysctl file
2098  * @filp: the file structure
2099  * @buffer: the user buffer
2100  * @lenp: the size of the user buffer
2101  * @ppos: file position
2102  * @ppos: the current position in the file
2103  *
2104  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2105  * values from/to the user buffer, treated as an ASCII string.
2106  * The values read are assumed to be in 1/1000 seconds, and
2107  * are converted into jiffies.
2108  *
2109  * Returns 0 on success.
2110  */
2111 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2112                              void __user *buffer, size_t *lenp, loff_t *ppos)
2113 {
2114         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2115                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2116 }
2117
2118 #else /* CONFIG_PROC_FS */
2119
2120 int proc_dostring(ctl_table *table, int write, struct file *filp,
2121                   void __user *buffer, size_t *lenp, loff_t *ppos)
2122 {
2123         return -ENOSYS;
2124 }
2125
2126 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
2127                             void __user *buffer, size_t *lenp, loff_t *ppos)
2128 {
2129         return -ENOSYS;
2130 }
2131
2132 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2133                   void __user *buffer, size_t *lenp, loff_t *ppos)
2134 {
2135         return -ENOSYS;
2136 }
2137
2138 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2139                         void __user *buffer, size_t *lenp, loff_t *ppos)
2140 {
2141         return -ENOSYS;
2142 }
2143
2144 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2145                     void __user *buffer, size_t *lenp, loff_t *ppos)
2146 {
2147         return -ENOSYS;
2148 }
2149
2150 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2151                     void __user *buffer, size_t *lenp, loff_t *ppos)
2152 {
2153         return -ENOSYS;
2154 }
2155
2156 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2157                     void __user *buffer, size_t *lenp, loff_t *ppos)
2158 {
2159         return -ENOSYS;
2160 }
2161
2162 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2163                              void __user *buffer, size_t *lenp, loff_t *ppos)
2164 {
2165         return -ENOSYS;
2166 }
2167
2168 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2169                     void __user *buffer, size_t *lenp, loff_t *ppos)
2170 {
2171         return -ENOSYS;
2172 }
2173
2174 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2175                                       struct file *filp,
2176                                       void __user *buffer,
2177                                       size_t *lenp, loff_t *ppos)
2178 {
2179     return -ENOSYS;
2180 }
2181
2182
2183 #endif /* CONFIG_PROC_FS */
2184
2185
2186 /*
2187  * General sysctl support routines
2188  */
2189
2190 /* The generic string strategy routine: */
2191 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2192                   void __user *oldval, size_t __user *oldlenp,
2193                   void __user *newval, size_t newlen, void **context)
2194 {
2195         if (!table->data || !table->maxlen)
2196                 return -ENOTDIR;
2197
2198         if (oldval && oldlenp) {
2199                 size_t bufsize;
2200                 if (get_user(bufsize, oldlenp))
2201                         return -EFAULT;
2202                 if (bufsize) {
2203                         size_t len = strlen(table->data), copied;
2204
2205                         /* This shouldn't trigger for a well-formed sysctl */
2206                         if (len > table->maxlen)
2207                                 len = table->maxlen;
2208
2209                         /* Copy up to a max of bufsize-1 bytes of the string */
2210                         copied = (len >= bufsize) ? bufsize - 1 : len;
2211
2212                         if (copy_to_user(oldval, table->data, copied) ||
2213                             put_user(0, (char __user *)(oldval + copied)))
2214                                 return -EFAULT;
2215                         if (put_user(len, oldlenp))
2216                                 return -EFAULT;
2217                 }
2218         }
2219         if (newval && newlen) {
2220                 size_t len = newlen;
2221                 if (len > table->maxlen)
2222                         len = table->maxlen;
2223                 if(copy_from_user(table->data, newval, len))
2224                         return -EFAULT;
2225                 if (len == table->maxlen)
2226                         len--;
2227                 ((char *) table->data)[len] = 0;
2228         }
2229         return 1;
2230 }
2231
2232 /*
2233  * This function makes sure that all of the integers in the vector
2234  * are between the minimum and maximum values given in the arrays
2235  * table->extra1 and table->extra2, respectively.
2236  */
2237 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2238                 void __user *oldval, size_t __user *oldlenp,
2239                 void __user *newval, size_t newlen, void **context)
2240 {
2241
2242         if (newval && newlen) {
2243                 int __user *vec = (int __user *) newval;
2244                 int *min = (int *) table->extra1;
2245                 int *max = (int *) table->extra2;
2246                 size_t length;
2247                 int i;
2248
2249                 if (newlen % sizeof(int) != 0)
2250                         return -EINVAL;
2251
2252                 if (!table->extra1 && !table->extra2)
2253                         return 0;
2254
2255                 if (newlen > table->maxlen)
2256                         newlen = table->maxlen;
2257                 length = newlen / sizeof(int);
2258
2259                 for (i = 0; i < length; i++) {
2260                         int value;
2261                         if (get_user(value, vec + i))
2262                                 return -EFAULT;
2263                         if (min && value < min[i])
2264                                 return -EINVAL;
2265                         if (max && value > max[i])
2266                                 return -EINVAL;
2267                 }
2268         }
2269         return 0;
2270 }
2271
2272 /* Strategy function to convert jiffies to seconds */
2273 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2274                 void __user *oldval, size_t __user *oldlenp,
2275                 void __user *newval, size_t newlen, void **context)
2276 {
2277         if (oldval) {
2278                 size_t olen;
2279                 if (oldlenp) {
2280                         if (get_user(olen, oldlenp))
2281                                 return -EFAULT;
2282                         if (olen!=sizeof(int))
2283                                 return -EINVAL;
2284                 }
2285                 if (put_user(*(int *)(table->data)/HZ, (int __user *)oldval) ||
2286                     (oldlenp && put_user(sizeof(int),oldlenp)))
2287                         return -EFAULT;
2288         }
2289         if (newval && newlen) {
2290                 int new;
2291                 if (newlen != sizeof(int))
2292                         return -EINVAL;
2293                 if (get_user(new, (int __user *)newval))
2294                         return -EFAULT;
2295                 *(int *)(table->data) = new*HZ;
2296         }
2297         return 1;
2298 }
2299
2300 /* Strategy function to convert jiffies to seconds */
2301 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2302                 void __user *oldval, size_t __user *oldlenp,
2303                 void __user *newval, size_t newlen, void **context)
2304 {
2305         if (oldval) {
2306                 size_t olen;
2307                 if (oldlenp) {
2308                         if (get_user(olen, oldlenp))
2309                                 return -EFAULT;
2310                         if (olen!=sizeof(int))
2311                                 return -EINVAL;
2312                 }
2313                 if (put_user(jiffies_to_msecs(*(int *)(table->data)), (int __user *)oldval) ||
2314                     (oldlenp && put_user(sizeof(int),oldlenp)))
2315                         return -EFAULT;
2316         }
2317         if (newval && newlen) {
2318                 int new;
2319                 if (newlen != sizeof(int))
2320                         return -EINVAL;
2321                 if (get_user(new, (int __user *)newval))
2322                         return -EFAULT;
2323                 *(int *)(table->data) = msecs_to_jiffies(new);
2324         }
2325         return 1;
2326 }
2327
2328 #else /* CONFIG_SYSCTL */
2329
2330
2331 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2332 {
2333         return -ENOSYS;
2334 }
2335
2336 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2337                   void __user *oldval, size_t __user *oldlenp,
2338                   void __user *newval, size_t newlen, void **context)
2339 {
2340         return -ENOSYS;
2341 }
2342
2343 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2344                 void __user *oldval, size_t __user *oldlenp,
2345                 void __user *newval, size_t newlen, void **context)
2346 {
2347         return -ENOSYS;
2348 }
2349
2350 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2351                 void __user *oldval, size_t __user *oldlenp,
2352                 void __user *newval, size_t newlen, void **context)
2353 {
2354         return -ENOSYS;
2355 }
2356
2357 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2358                 void __user *oldval, size_t __user *oldlenp,
2359                 void __user *newval, size_t newlen, void **context)
2360 {
2361         return -ENOSYS;
2362 }
2363
2364 int proc_dostring(ctl_table *table, int write, struct file *filp,
2365                   void __user *buffer, size_t *lenp, loff_t *ppos)
2366 {
2367         return -ENOSYS;
2368 }
2369
2370 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2371                   void __user *buffer, size_t *lenp, loff_t *ppos)
2372 {
2373         return -ENOSYS;
2374 }
2375
2376 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2377                         void __user *buffer, size_t *lenp, loff_t *ppos)
2378 {
2379         return -ENOSYS;
2380 }
2381
2382 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2383                     void __user *buffer, size_t *lenp, loff_t *ppos)
2384 {
2385         return -ENOSYS;
2386 }
2387
2388 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2389                           void __user *buffer, size_t *lenp, loff_t *ppos)
2390 {
2391         return -ENOSYS;
2392 }
2393
2394 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2395                           void __user *buffer, size_t *lenp, loff_t *ppos)
2396 {
2397         return -ENOSYS;
2398 }
2399
2400 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2401                              void __user *buffer, size_t *lenp, loff_t *ppos)
2402 {
2403         return -ENOSYS;
2404 }
2405
2406 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2407                     void __user *buffer, size_t *lenp, loff_t *ppos)
2408 {
2409         return -ENOSYS;
2410 }
2411
2412 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2413                                       struct file *filp,
2414                                       void __user *buffer,
2415                                       size_t *lenp, loff_t *ppos)
2416 {
2417     return -ENOSYS;
2418 }
2419
2420 struct ctl_table_header * register_sysctl_table(ctl_table * table,
2421                                                 int insert_at_head)
2422 {
2423         return NULL;
2424 }
2425
2426 void unregister_sysctl_table(struct ctl_table_header * table)
2427 {
2428 }
2429
2430 #endif /* CONFIG_SYSCTL */
2431
2432 /*
2433  * No sense putting this after each symbol definition, twice,
2434  * exception granted :-)
2435  */
2436 EXPORT_SYMBOL(proc_dointvec);
2437 EXPORT_SYMBOL(proc_dointvec_jiffies);
2438 EXPORT_SYMBOL(proc_dointvec_minmax);
2439 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2440 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2441 EXPORT_SYMBOL(proc_dostring);
2442 EXPORT_SYMBOL(proc_doulongvec_minmax);
2443 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2444 EXPORT_SYMBOL(register_sysctl_table);
2445 EXPORT_SYMBOL(sysctl_intvec);
2446 EXPORT_SYMBOL(sysctl_jiffies);
2447 EXPORT_SYMBOL(sysctl_ms_jiffies);
2448 EXPORT_SYMBOL(sysctl_string);
2449 EXPORT_SYMBOL(unregister_sysctl_table);