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/kobject.h>
  35 #include <linux/net.h>
  36 #include <linux/sysrq.h>
  37 #include <linux/highuid.h>
  38 #include <linux/writeback.h>
  39 #include <linux/hugetlb.h>
  40 #include <linux/security.h>
  41 #include <linux/initrd.h>
  42 #include <linux/times.h>
  43 #include <linux/limits.h>
  44 #include <linux/dcache.h>
  45 #include <linux/syscalls.h>
  46
  47 #include <asm/uaccess.h>
  48 #include <asm/processor.h>
  49
  50 #ifdef CONFIG_ROOT_NFS
  51 #include <linux/nfs_fs.h>
  52 #endif
  53
  54 #if defined(CONFIG_SYSCTL)
  55
  56 /* External variables not in a header file. */
  57 extern int C_A_D;
  58 extern int sysctl_overcommit_memory;
  59 extern int sysctl_overcommit_ratio;
  60 extern int max_threads;
  61 extern int sysrq_enabled;
  62 extern int core_uses_pid;
  63 extern int suid_dumpable;
  64 extern char core_pattern[];
  65 extern int cad_pid;
  66 extern int pid_max;
  67 extern int min_free_kbytes;
  68 extern int printk_ratelimit_jiffies;
  69 extern int printk_ratelimit_burst;
  70 extern int pid_max_min, pid_max_max;
  71 extern int sysctl_drop_caches;
  72
  73 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
  74 int unknown_nmi_panic;
  75 extern int proc_unknown_nmi_panic(ctl_table *, int, struct file *,
  76                                   void __user *, size_t *, loff_t *);
  77 #endif
  78
  79 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
  80 static int maxolduid = 65535;
  81 static int minolduid;
  82
  83 static int ngroups_max = NGROUPS_MAX;
  84
  85 #ifdef CONFIG_KMOD
  86 extern char modprobe_path[];
  87 #endif
  88 #ifdef CONFIG_CHR_DEV_SG
  89 extern int sg_big_buff;
  90 #endif
  91 #ifdef CONFIG_SYSVIPC
  92 extern size_t shm_ctlmax;
  93 extern size_t shm_ctlall;
  94 extern int shm_ctlmni;
  95 extern int msg_ctlmax;
  96 extern int msg_ctlmnb;
  97 extern int msg_ctlmni;
  98 extern int sem_ctls[];
  99 #endif
 100
 101 #ifdef __sparc__
 102 extern char reboot_command [];
 103 extern int stop_a_enabled;
 104 extern int scons_pwroff;
 105 #endif
 106
 107 #ifdef __hppa__
 108 extern int pwrsw_enabled;
 109 extern int unaligned_enabled;
 110 #endif
 111
 112 #ifdef CONFIG_S390
 113 #ifdef CONFIG_MATHEMU
 114 extern int sysctl_ieee_emulation_warnings;
 115 #endif
 116 extern int sysctl_userprocess_debug;
 117 extern int spin_retry;
 118 #endif
 119
 120 extern int sysctl_hz_timer;
 121
 122 #ifdef CONFIG_BSD_PROCESS_ACCT
 123 extern int acct_parm[];
 124 #endif
 125
 126 int randomize_va_space = 1;
 127
 128 static int parse_table(int __user *, int, void __user *, size_t __user *, void __user *, size_t,
 129                        ctl_table *, void **);
 130 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
 131                   void __user *buffer, size_t *lenp, loff_t *ppos);
 132
 133 static ctl_table root_table[];
 134 static struct ctl_table_header root_table_header =
 135         { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
 136
 137 static ctl_table kern_table[];
 138 static ctl_table vm_table[];
 139 static ctl_table proc_table[];
 140 static ctl_table fs_table[];
 141 static ctl_table debug_table[];
 142 static ctl_table dev_table[];
 143 extern ctl_table random_table[];
 144 #ifdef CONFIG_UNIX98_PTYS
 145 extern ctl_table pty_table[];
 146 #endif
 147 #ifdef CONFIG_INOTIFY
 148 extern ctl_table inotify_table[];
 149 #endif
 150
 151 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 152 int sysctl_legacy_va_layout;
 153 #endif
 154
 155 /* /proc declarations: */
 156
 157 #ifdef CONFIG_PROC_FS
 158
 159 static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
 160 static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
 161 static int proc_opensys(struct inode *, struct file *);
 162
 163 struct file_operations proc_sys_file_operations = {
 164         .open           = proc_opensys,
 165         .read           = proc_readsys,
 166         .write          = proc_writesys,
 167 };
 168
 169 extern struct proc_dir_entry *proc_sys_root;
 170
 171 static void register_proc_table(ctl_table *, struct proc_dir_entry *, void *);
 172 static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
 173 #endif
 174
 175 /* The default sysctl tables: */
 176
 177 static ctl_table root_table[] = {
 178         {
 179                 .ctl_name       = CTL_KERN,
 180                 .procname       = "kernel",
 181                 .mode           = 0555,
 182                 .child          = kern_table,
 183         },
 184         {
 185                 .ctl_name       = CTL_VM,
 186                 .procname       = "vm",
 187                 .mode           = 0555,
 188                 .child          = vm_table,
 189         },
 190 #ifdef CONFIG_NET
 191         {
 192                 .ctl_name       = CTL_NET,
 193                 .procname       = "net",
 194                 .mode           = 0555,
 195                 .child          = net_table,
 196         },
 197 #endif
 198         {
 199                 .ctl_name       = CTL_PROC,
 200                 .procname       = "proc",
 201                 .mode           = 0555,
 202                 .child          = proc_table,
 203         },
 204         {
 205                 .ctl_name       = CTL_FS,
 206                 .procname       = "fs",
 207                 .mode           = 0555,
 208                 .child          = fs_table,
 209         },
 210         {
 211                 .ctl_name       = CTL_DEBUG,
 212                 .procname       = "debug",
 213                 .mode           = 0555,
 214                 .child          = debug_table,
 215         },
 216         {
 217                 .ctl_name       = CTL_DEV,
 218                 .procname       = "dev",
 219                 .mode           = 0555,
 220                 .child          = dev_table,
 221         },
 222
 223         { .ctl_name = 0 }
 224 };
 225
 226 static ctl_table kern_table[] = {
 227         {
 228                 .ctl_name       = KERN_OSTYPE,
 229                 .procname       = "ostype",
 230                 .data           = system_utsname.sysname,
 231                 .maxlen         = sizeof(system_utsname.sysname),
 232                 .mode           = 0444,
 233                 .proc_handler   = &proc_doutsstring,
 234                 .strategy       = &sysctl_string,
 235         },
 236         {
 237                 .ctl_name       = KERN_OSRELEASE,
 238                 .procname       = "osrelease",
 239                 .data           = system_utsname.release,
 240                 .maxlen         = sizeof(system_utsname.release),
 241                 .mode           = 0444,
 242                 .proc_handler   = &proc_doutsstring,
 243                 .strategy       = &sysctl_string,
 244         },
 245         {
 246                 .ctl_name       = KERN_VERSION,
 247                 .procname       = "version",
 248                 .data           = system_utsname.version,
 249                 .maxlen         = sizeof(system_utsname.version),
 250                 .mode           = 0444,
 251                 .proc_handler   = &proc_doutsstring,
 252                 .strategy       = &sysctl_string,
 253         },
 254         {
 255                 .ctl_name       = KERN_NODENAME,
 256                 .procname       = "hostname",
 257                 .data           = system_utsname.nodename,
 258                 .maxlen         = sizeof(system_utsname.nodename),
 259                 .mode           = 0644,
 260                 .proc_handler   = &proc_doutsstring,
 261                 .strategy       = &sysctl_string,
 262         },
 263         {
 264                 .ctl_name       = KERN_DOMAINNAME,
 265                 .procname       = "domainname",
 266                 .data           = system_utsname.domainname,
 267                 .maxlen         = sizeof(system_utsname.domainname),
 268                 .mode           = 0644,
 269                 .proc_handler   = &proc_doutsstring,
 270                 .strategy       = &sysctl_string,
 271         },
 272         {
 273                 .ctl_name       = KERN_PANIC,
 274                 .procname       = "panic",
 275                 .data           = &panic_timeout,
 276                 .maxlen         = sizeof(int),
 277                 .mode           = 0644,
 278                 .proc_handler   = &proc_dointvec,
 279         },
 280         {
 281                 .ctl_name       = KERN_CORE_USES_PID,
 282                 .procname       = "core_uses_pid",
 283                 .data           = &core_uses_pid,
 284                 .maxlen         = sizeof(int),
 285                 .mode           = 0644,
 286                 .proc_handler   = &proc_dointvec,
 287         },
 288         {
 289                 .ctl_name       = KERN_CORE_PATTERN,
 290                 .procname       = "core_pattern",
 291                 .data           = core_pattern,
 292                 .maxlen         = 64,
 293                 .mode           = 0644,
 294                 .proc_handler   = &proc_dostring,
 295                 .strategy       = &sysctl_string,
 296         },
 297         {
 298                 .ctl_name       = KERN_TAINTED,
 299                 .procname       = "tainted",
 300                 .data           = &tainted,
 301                 .maxlen         = sizeof(int),
 302                 .mode           = 0444,
 303                 .proc_handler   = &proc_dointvec,
 304         },
 305         {
 306                 .ctl_name       = KERN_CAP_BSET,
 307                 .procname       = "cap-bound",
 308                 .data           = &cap_bset,
 309                 .maxlen         = sizeof(kernel_cap_t),
 310                 .mode           = 0600,
 311                 .proc_handler   = &proc_dointvec_bset,
 312         },
 313 #ifdef CONFIG_BLK_DEV_INITRD
 314         {
 315                 .ctl_name       = KERN_REALROOTDEV,
 316                 .procname       = "real-root-dev",
 317                 .data           = &real_root_dev,
 318                 .maxlen         = sizeof(int),
 319                 .mode           = 0644,
 320                 .proc_handler   = &proc_dointvec,
 321         },
 322 #endif
 323 #ifdef __sparc__
 324         {
 325                 .ctl_name       = KERN_SPARC_REBOOT,
 326                 .procname       = "reboot-cmd",
 327                 .data           = reboot_command,
 328                 .maxlen         = 256,
 329                 .mode           = 0644,
 330                 .proc_handler   = &proc_dostring,
 331                 .strategy       = &sysctl_string,
 332         },
 333         {
 334                 .ctl_name       = KERN_SPARC_STOP_A,
 335                 .procname       = "stop-a",
 336                 .data           = &stop_a_enabled,
 337                 .maxlen         = sizeof (int),
 338                 .mode           = 0644,
 339                 .proc_handler   = &proc_dointvec,
 340         },
 341         {
 342                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 343                 .procname       = "scons-poweroff",
 344                 .data           = &scons_pwroff,
 345                 .maxlen         = sizeof (int),
 346                 .mode           = 0644,
 347                 .proc_handler   = &proc_dointvec,
 348         },
 349 #endif
 350 #ifdef __hppa__
 351         {
 352                 .ctl_name       = KERN_HPPA_PWRSW,
 353                 .procname       = "soft-power",
 354                 .data           = &pwrsw_enabled,
 355                 .maxlen         = sizeof (int),
 356                 .mode           = 0644,
 357                 .proc_handler   = &proc_dointvec,
 358         },
 359         {
 360                 .ctl_name       = KERN_HPPA_UNALIGNED,
 361                 .procname       = "unaligned-trap",
 362                 .data           = &unaligned_enabled,
 363                 .maxlen         = sizeof (int),
 364                 .mode           = 0644,
 365                 .proc_handler   = &proc_dointvec,
 366         },
 367 #endif
 368         {
 369                 .ctl_name       = KERN_CTLALTDEL,
 370                 .procname       = "ctrl-alt-del",
 371                 .data           = &C_A_D,
 372                 .maxlen         = sizeof(int),
 373                 .mode           = 0644,
 374                 .proc_handler   = &proc_dointvec,
 375         },
 376         {
 377                 .ctl_name       = KERN_PRINTK,
 378                 .procname       = "printk",
 379                 .data           = &console_loglevel,
 380                 .maxlen         = 4*sizeof(int),
 381                 .mode           = 0644,
 382                 .proc_handler   = &proc_dointvec,
 383         },
 384 #ifdef CONFIG_KMOD
 385         {
 386                 .ctl_name       = KERN_MODPROBE,
 387                 .procname       = "modprobe",
 388                 .data           = &modprobe_path,
 389                 .maxlen         = KMOD_PATH_LEN,
 390                 .mode           = 0644,
 391                 .proc_handler   = &proc_dostring,
 392                 .strategy       = &sysctl_string,
 393         },
 394 #endif
 395 #ifdef CONFIG_HOTPLUG
 396         {
 397                 .ctl_name       = KERN_HOTPLUG,
 398                 .procname       = "hotplug",
 399                 .data           = &uevent_helper,
 400                 .maxlen         = UEVENT_HELPER_PATH_LEN,
 401                 .mode           = 0644,
 402                 .proc_handler   = &proc_dostring,
 403                 .strategy       = &sysctl_string,
 404         },
 405 #endif
 406 #ifdef CONFIG_CHR_DEV_SG
 407         {
 408                 .ctl_name       = KERN_SG_BIG_BUFF,
 409                 .procname       = "sg-big-buff",
 410                 .data           = &sg_big_buff,
 411                 .maxlen         = sizeof (int),
 412                 .mode           = 0444,
 413                 .proc_handler   = &proc_dointvec,
 414         },
 415 #endif
 416 #ifdef CONFIG_BSD_PROCESS_ACCT
 417         {
 418                 .ctl_name       = KERN_ACCT,
 419                 .procname       = "acct",
 420                 .data           = &acct_parm,
 421                 .maxlen         = 3*sizeof(int),
 422                 .mode           = 0644,
 423                 .proc_handler   = &proc_dointvec,
 424         },
 425 #endif
 426 #ifdef CONFIG_SYSVIPC
 427         {
 428                 .ctl_name       = KERN_SHMMAX,
 429                 .procname       = "shmmax",
 430                 .data           = &shm_ctlmax,
 431                 .maxlen         = sizeof (size_t),
 432                 .mode           = 0644,
 433                 .proc_handler   = &proc_doulongvec_minmax,
 434         },
 435         {
 436                 .ctl_name       = KERN_SHMALL,
 437                 .procname       = "shmall",
 438                 .data           = &shm_ctlall,
 439                 .maxlen         = sizeof (size_t),
 440                 .mode           = 0644,
 441                 .proc_handler   = &proc_doulongvec_minmax,
 442         },
 443         {
 444                 .ctl_name       = KERN_SHMMNI,
 445                 .procname       = "shmmni",
 446                 .data           = &shm_ctlmni,
 447                 .maxlen         = sizeof (int),
 448                 .mode           = 0644,
 449                 .proc_handler   = &proc_dointvec,
 450         },
 451         {
 452                 .ctl_name       = KERN_MSGMAX,
 453                 .procname       = "msgmax",
 454                 .data           = &msg_ctlmax,
 455                 .maxlen         = sizeof (int),
 456                 .mode           = 0644,
 457                 .proc_handler   = &proc_dointvec,
 458         },
 459         {
 460                 .ctl_name       = KERN_MSGMNI,
 461                 .procname       = "msgmni",
 462                 .data           = &msg_ctlmni,
 463                 .maxlen         = sizeof (int),
 464                 .mode           = 0644,
 465                 .proc_handler   = &proc_dointvec,
 466         },
 467         {
 468                 .ctl_name       = KERN_MSGMNB,
 469                 .procname       =  "msgmnb",
 470                 .data           = &msg_ctlmnb,
 471                 .maxlen         = sizeof (int),
 472                 .mode           = 0644,
 473                 .proc_handler   = &proc_dointvec,
 474         },
 475         {
 476                 .ctl_name       = KERN_SEM,
 477                 .procname       = "sem",
 478                 .data           = &sem_ctls,
 479                 .maxlen         = 4*sizeof (int),
 480                 .mode           = 0644,
 481                 .proc_handler   = &proc_dointvec,
 482         },
 483 #endif
 484 #ifdef CONFIG_MAGIC_SYSRQ
 485         {
 486                 .ctl_name       = KERN_SYSRQ,
 487                 .procname       = "sysrq",
 488                 .data           = &sysrq_enabled,
 489                 .maxlen         = sizeof (int),
 490                 .mode           = 0644,
 491                 .proc_handler   = &proc_dointvec,
 492         },
 493 #endif
 494         {
 495                 .ctl_name       = KERN_CADPID,
 496                 .procname       = "cad_pid",
 497                 .data           = &cad_pid,
 498                 .maxlen         = sizeof (int),
 499                 .mode           = 0600,
 500                 .proc_handler   = &proc_dointvec,
 501         },
 502         {
 503                 .ctl_name       = KERN_MAX_THREADS,
 504                 .procname       = "threads-max",
 505                 .data           = &max_threads,
 506                 .maxlen         = sizeof(int),
 507                 .mode           = 0644,
 508                 .proc_handler   = &proc_dointvec,
 509         },
 510         {
 511                 .ctl_name       = KERN_RANDOM,
 512                 .procname       = "random",
 513                 .mode           = 0555,
 514                 .child          = random_table,
 515         },
 516 #ifdef CONFIG_UNIX98_PTYS
 517         {
 518                 .ctl_name       = KERN_PTY,
 519                 .procname       = "pty",
 520                 .mode           = 0555,
 521                 .child          = pty_table,
 522         },
 523 #endif
 524         {
 525                 .ctl_name       = KERN_OVERFLOWUID,
 526                 .procname       = "overflowuid",
 527                 .data           = &overflowuid,
 528                 .maxlen         = sizeof(int),
 529                 .mode           = 0644,
 530                 .proc_handler   = &proc_dointvec_minmax,
 531                 .strategy       = &sysctl_intvec,
 532                 .extra1         = &minolduid,
 533                 .extra2         = &maxolduid,
 534         },
 535         {
 536                 .ctl_name       = KERN_OVERFLOWGID,
 537                 .procname       = "overflowgid",
 538                 .data           = &overflowgid,
 539                 .maxlen         = sizeof(int),
 540                 .mode           = 0644,
 541                 .proc_handler   = &proc_dointvec_minmax,
 542                 .strategy       = &sysctl_intvec,
 543                 .extra1         = &minolduid,
 544                 .extra2         = &maxolduid,
 545         },
 546 #ifdef CONFIG_S390
 547 #ifdef CONFIG_MATHEMU
 548         {
 549                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 550                 .procname       = "ieee_emulation_warnings",
 551                 .data           = &sysctl_ieee_emulation_warnings,
 552                 .maxlen         = sizeof(int),
 553                 .mode           = 0644,
 554                 .proc_handler   = &proc_dointvec,
 555         },
 556 #endif
 557 #ifdef CONFIG_NO_IDLE_HZ
 558         {
 559                 .ctl_name       = KERN_HZ_TIMER,
 560                 .procname       = "hz_timer",
 561                 .data           = &sysctl_hz_timer,
 562                 .maxlen         = sizeof(int),
 563                 .mode           = 0644,
 564                 .proc_handler   = &proc_dointvec,
 565         },
 566 #endif
 567         {
 568                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 569                 .procname       = "userprocess_debug",
 570                 .data           = &sysctl_userprocess_debug,
 571                 .maxlen         = sizeof(int),
 572                 .mode           = 0644,
 573                 .proc_handler   = &proc_dointvec,
 574         },
 575 #endif
 576         {
 577                 .ctl_name       = KERN_PIDMAX,
 578                 .procname       = "pid_max",
 579                 .data           = &pid_max,
 580                 .maxlen         = sizeof (int),
 581                 .mode           = 0644,
 582                 .proc_handler   = &proc_dointvec_minmax,
 583                 .strategy       = sysctl_intvec,
 584                 .extra1         = &pid_max_min,
 585                 .extra2         = &pid_max_max,
 586         },
 587         {
 588                 .ctl_name       = KERN_PANIC_ON_OOPS,
 589                 .procname       = "panic_on_oops",
 590                 .data           = &panic_on_oops,
 591                 .maxlen         = sizeof(int),
 592                 .mode           = 0644,
 593                 .proc_handler   = &proc_dointvec,
 594         },
 595         {
 596                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 597                 .procname       = "printk_ratelimit",
 598                 .data           = &printk_ratelimit_jiffies,
 599                 .maxlen         = sizeof(int),
 600                 .mode           = 0644,
 601                 .proc_handler   = &proc_dointvec_jiffies,
 602                 .strategy       = &sysctl_jiffies,
 603         },
 604         {
 605                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 606                 .procname       = "printk_ratelimit_burst",
 607                 .data           = &printk_ratelimit_burst,
 608                 .maxlen         = sizeof(int),
 609                 .mode           = 0644,
 610                 .proc_handler   = &proc_dointvec,
 611         },
 612         {
 613                 .ctl_name       = KERN_NGROUPS_MAX,
 614                 .procname       = "ngroups_max",
 615                 .data           = &ngroups_max,
 616                 .maxlen         = sizeof (int),
 617                 .mode           = 0444,
 618                 .proc_handler   = &proc_dointvec,
 619         },
 620 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 621         {
 622                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
 623                 .procname       = "unknown_nmi_panic",
 624                 .data           = &unknown_nmi_panic,
 625                 .maxlen         = sizeof (int),
 626                 .mode           = 0644,
 627                 .proc_handler   = &proc_unknown_nmi_panic,
 628         },
 629 #endif
 630 #if defined(CONFIG_X86)
 631         {
 632                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 633                 .procname       = "bootloader_type",
 634                 .data           = &bootloader_type,
 635                 .maxlen         = sizeof (int),
 636                 .mode           = 0444,
 637                 .proc_handler   = &proc_dointvec,
 638         },
 639 #endif
 640         {
 641                 .ctl_name       = KERN_RANDOMIZE,
 642                 .procname       = "randomize_va_space",
 643                 .data           = &randomize_va_space,
 644                 .maxlen         = sizeof(int),
 645                 .mode           = 0644,
 646                 .proc_handler   = &proc_dointvec,
 647         },
 648 #if defined(CONFIG_S390)
 649         {
 650                 .ctl_name       = KERN_SPIN_RETRY,
 651                 .procname       = "spin_retry",
 652                 .data           = &spin_retry,
 653                 .maxlen         = sizeof (int),
 654                 .mode           = 0644,
 655                 .proc_handler   = &proc_dointvec,
 656         },
 657 #endif
 658         { .ctl_name = 0 }
 659 };
 660
 661 /* Constants for minimum and maximum testing in vm_table.
 662    We use these as one-element integer vectors. */
 663 static int zero;
 664 static int one_hundred = 100;
 665
 666
 667 static ctl_table vm_table[] = {
 668         {
 669                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
 670                 .procname       = "overcommit_memory",
 671                 .data           = &sysctl_overcommit_memory,
 672                 .maxlen         = sizeof(sysctl_overcommit_memory),
 673                 .mode           = 0644,
 674                 .proc_handler   = &proc_dointvec,
 675         },
 676         {
 677                 .ctl_name       = VM_OVERCOMMIT_RATIO,
 678                 .procname       = "overcommit_ratio",
 679                 .data           = &sysctl_overcommit_ratio,
 680                 .maxlen         = sizeof(sysctl_overcommit_ratio),
 681                 .mode           = 0644,
 682                 .proc_handler   = &proc_dointvec,
 683         },
 684         {
 685                 .ctl_name       = VM_PAGE_CLUSTER,
 686                 .procname       = "page-cluster",
 687                 .data           = &page_cluster,
 688                 .maxlen         = sizeof(int),
 689                 .mode           = 0644,
 690                 .proc_handler   = &proc_dointvec,
 691         },
 692         {
 693                 .ctl_name       = VM_DIRTY_BACKGROUND,
 694                 .procname       = "dirty_background_ratio",
 695                 .data           = &dirty_background_ratio,
 696                 .maxlen         = sizeof(dirty_background_ratio),
 697                 .mode           = 0644,
 698                 .proc_handler   = &proc_dointvec_minmax,
 699                 .strategy       = &sysctl_intvec,
 700                 .extra1         = &zero,
 701                 .extra2         = &one_hundred,
 702         },
 703         {
 704                 .ctl_name       = VM_DIRTY_RATIO,
 705                 .procname       = "dirty_ratio",
 706                 .data           = &vm_dirty_ratio,
 707                 .maxlen         = sizeof(vm_dirty_ratio),
 708                 .mode           = 0644,
 709                 .proc_handler   = &proc_dointvec_minmax,
 710                 .strategy       = &sysctl_intvec,
 711                 .extra1         = &zero,
 712                 .extra2         = &one_hundred,
 713         },
 714         {
 715                 .ctl_name       = VM_DIRTY_WB_CS,
 716                 .procname       = "dirty_writeback_centisecs",
 717                 .data           = &dirty_writeback_centisecs,
 718                 .maxlen         = sizeof(dirty_writeback_centisecs),
 719                 .mode           = 0644,
 720                 .proc_handler   = &dirty_writeback_centisecs_handler,
 721         },
 722         {
 723                 .ctl_name       = VM_DIRTY_EXPIRE_CS,
 724                 .procname       = "dirty_expire_centisecs",
 725                 .data           = &dirty_expire_centisecs,
 726                 .maxlen         = sizeof(dirty_expire_centisecs),
 727                 .mode           = 0644,
 728                 .proc_handler   = &proc_dointvec,
 729         },
 730         {
 731                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
 732                 .procname       = "nr_pdflush_threads",
 733                 .data           = &nr_pdflush_threads,
 734                 .maxlen         = sizeof nr_pdflush_threads,
 735                 .mode           = 0444 /* read-only*/,
 736                 .proc_handler   = &proc_dointvec,
 737         },
 738         {
 739                 .ctl_name       = VM_SWAPPINESS,
 740                 .procname       = "swappiness",
 741                 .data           = &vm_swappiness,
 742                 .maxlen         = sizeof(vm_swappiness),
 743                 .mode           = 0644,
 744                 .proc_handler   = &proc_dointvec_minmax,
 745                 .strategy       = &sysctl_intvec,
 746                 .extra1         = &zero,
 747                 .extra2         = &one_hundred,
 748         },
 749 #ifdef CONFIG_HUGETLB_PAGE
 750          {
 751                 .ctl_name       = VM_HUGETLB_PAGES,
 752                 .procname       = "nr_hugepages",
 753                 .data           = &max_huge_pages,
 754                 .maxlen         = sizeof(unsigned long),
 755                 .mode           = 0644,
 756                 .proc_handler   = &hugetlb_sysctl_handler,
 757                 .extra1         = (void *)&hugetlb_zero,
 758                 .extra2         = (void *)&hugetlb_infinity,
 759          },
 760          {
 761                 .ctl_name       = VM_HUGETLB_GROUP,
 762                 .procname       = "hugetlb_shm_group",
 763                 .data           = &sysctl_hugetlb_shm_group,
 764                 .maxlen         = sizeof(gid_t),
 765                 .mode           = 0644,
 766                 .proc_handler   = &proc_dointvec,
 767          },
 768 #endif
 769         {
 770                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
 771                 .procname       = "lowmem_reserve_ratio",
 772                 .data           = &sysctl_lowmem_reserve_ratio,
 773                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
 774                 .mode           = 0644,
 775                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
 776                 .strategy       = &sysctl_intvec,
 777         },
 778         {
 779                 .ctl_name       = VM_DROP_PAGECACHE,
 780                 .procname       = "drop_caches",
 781                 .data           = &sysctl_drop_caches,
 782                 .maxlen         = sizeof(int),
 783                 .mode           = 0644,
 784                 .proc_handler   = drop_caches_sysctl_handler,
 785                 .strategy       = &sysctl_intvec,
 786         },
 787         {
 788                 .ctl_name       = VM_MIN_FREE_KBYTES,
 789                 .procname       = "min_free_kbytes",
 790                 .data           = &min_free_kbytes,
 791                 .maxlen         = sizeof(min_free_kbytes),
 792                 .mode           = 0644,
 793                 .proc_handler   = &min_free_kbytes_sysctl_handler,
 794                 .strategy       = &sysctl_intvec,
 795                 .extra1         = &zero,
 796         },
 797 #ifdef CONFIG_MMU
 798         {
 799                 .ctl_name       = VM_MAX_MAP_COUNT,
 800                 .procname       = "max_map_count",
 801                 .data           = &sysctl_max_map_count,
 802                 .maxlen         = sizeof(sysctl_max_map_count),
 803                 .mode           = 0644,
 804                 .proc_handler   = &proc_dointvec
 805         },
 806 #endif
 807         {
 808                 .ctl_name       = VM_LAPTOP_MODE,
 809                 .procname       = "laptop_mode",
 810                 .data           = &laptop_mode,
 811                 .maxlen         = sizeof(laptop_mode),
 812                 .mode           = 0644,
 813                 .proc_handler   = &proc_dointvec,
 814                 .strategy       = &sysctl_intvec,
 815                 .extra1         = &zero,
 816         },
 817         {
 818                 .ctl_name       = VM_BLOCK_DUMP,
 819                 .procname       = "block_dump",
 820                 .data           = &block_dump,
 821                 .maxlen         = sizeof(block_dump),
 822                 .mode           = 0644,
 823                 .proc_handler   = &proc_dointvec,
 824                 .strategy       = &sysctl_intvec,
 825                 .extra1         = &zero,
 826         },
 827         {
 828                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
 829                 .procname       = "vfs_cache_pressure",
 830                 .data           = &sysctl_vfs_cache_pressure,
 831                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
 832                 .mode           = 0644,
 833                 .proc_handler   = &proc_dointvec,
 834                 .strategy       = &sysctl_intvec,
 835                 .extra1         = &zero,
 836         },
 837 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 838         {
 839                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
 840                 .procname       = "legacy_va_layout",
 841                 .data           = &sysctl_legacy_va_layout,
 842                 .maxlen         = sizeof(sysctl_legacy_va_layout),
 843                 .mode           = 0644,
 844                 .proc_handler   = &proc_dointvec,
 845                 .strategy       = &sysctl_intvec,
 846                 .extra1         = &zero,
 847         },
 848 #endif
 849 #ifdef CONFIG_SWAP
 850         {
 851                 .ctl_name       = VM_SWAP_TOKEN_TIMEOUT,
 852                 .procname       = "swap_token_timeout",
 853                 .data           = &swap_token_default_timeout,
 854                 .maxlen         = sizeof(swap_token_default_timeout),
 855                 .mode           = 0644,
 856                 .proc_handler   = &proc_dointvec_jiffies,
 857                 .strategy       = &sysctl_jiffies,
 858         },
 859 #endif
 860         { .ctl_name = 0 }
 861 };
 862
 863 static ctl_table proc_table[] = {
 864         { .ctl_name = 0 }
 865 };
 866
 867 static ctl_table fs_table[] = {
 868         {
 869                 .ctl_name       = FS_NRINODE,
 870                 .procname       = "inode-nr",
 871                 .data           = &inodes_stat,
 872                 .maxlen         = 2*sizeof(int),
 873                 .mode           = 0444,
 874                 .proc_handler   = &proc_dointvec,
 875         },
 876         {
 877                 .ctl_name       = FS_STATINODE,
 878                 .procname       = "inode-state",
 879                 .data           = &inodes_stat,
 880                 .maxlen         = 7*sizeof(int),
 881                 .mode           = 0444,
 882                 .proc_handler   = &proc_dointvec,
 883         },
 884         {
 885                 .ctl_name       = FS_NRFILE,
 886                 .procname       = "file-nr",
 887                 .data           = &files_stat,
 888                 .maxlen         = 3*sizeof(int),
 889                 .mode           = 0444,
 890                 .proc_handler   = &proc_dointvec,
 891         },
 892         {
 893                 .ctl_name       = FS_MAXFILE,
 894                 .procname       = "file-max",
 895                 .data           = &files_stat.max_files,
 896                 .maxlen         = sizeof(int),
 897                 .mode           = 0644,
 898                 .proc_handler   = &proc_dointvec,
 899         },
 900         {
 901                 .ctl_name       = FS_DENTRY,
 902                 .procname       = "dentry-state",
 903                 .data           = &dentry_stat,
 904                 .maxlen         = 6*sizeof(int),
 905                 .mode           = 0444,
 906                 .proc_handler   = &proc_dointvec,
 907         },
 908         {
 909                 .ctl_name       = FS_OVERFLOWUID,
 910                 .procname       = "overflowuid",
 911                 .data           = &fs_overflowuid,
 912                 .maxlen         = sizeof(int),
 913                 .mode           = 0644,
 914                 .proc_handler   = &proc_dointvec_minmax,
 915                 .strategy       = &sysctl_intvec,
 916                 .extra1         = &minolduid,
 917                 .extra2         = &maxolduid,
 918         },
 919         {
 920                 .ctl_name       = FS_OVERFLOWGID,
 921                 .procname       = "overflowgid",
 922                 .data           = &fs_overflowgid,
 923                 .maxlen         = sizeof(int),
 924                 .mode           = 0644,
 925                 .proc_handler   = &proc_dointvec_minmax,
 926                 .strategy       = &sysctl_intvec,
 927                 .extra1         = &minolduid,
 928                 .extra2         = &maxolduid,
 929         },
 930         {
 931                 .ctl_name       = FS_LEASES,
 932                 .procname       = "leases-enable",
 933                 .data           = &leases_enable,
 934                 .maxlen         = sizeof(int),
 935                 .mode           = 0644,
 936                 .proc_handler   = &proc_dointvec,
 937         },
 938 #ifdef CONFIG_DNOTIFY
 939         {
 940                 .ctl_name       = FS_DIR_NOTIFY,
 941                 .procname       = "dir-notify-enable",
 942                 .data           = &dir_notify_enable,
 943                 .maxlen         = sizeof(int),
 944                 .mode           = 0644,
 945                 .proc_handler   = &proc_dointvec,
 946         },
 947 #endif
 948 #ifdef CONFIG_MMU
 949         {
 950                 .ctl_name       = FS_LEASE_TIME,
 951                 .procname       = "lease-break-time",
 952                 .data           = &lease_break_time,
 953                 .maxlen         = sizeof(int),
 954                 .mode           = 0644,
 955                 .proc_handler   = &proc_dointvec,
 956         },
 957         {
 958                 .ctl_name       = FS_AIO_NR,
 959                 .procname       = "aio-nr",
 960                 .data           = &aio_nr,
 961                 .maxlen         = sizeof(aio_nr),
 962                 .mode           = 0444,
 963                 .proc_handler   = &proc_doulongvec_minmax,
 964         },
 965         {
 966                 .ctl_name       = FS_AIO_MAX_NR,
 967                 .procname       = "aio-max-nr",
 968                 .data           = &aio_max_nr,
 969                 .maxlen         = sizeof(aio_max_nr),
 970                 .mode           = 0644,
 971                 .proc_handler   = &proc_doulongvec_minmax,
 972         },
 973 #ifdef CONFIG_INOTIFY
 974         {
 975                 .ctl_name       = FS_INOTIFY,
 976                 .procname       = "inotify",
 977                 .mode           = 0555,
 978                 .child          = inotify_table,
 979         },
 980 #endif
 981 #endif
 982         {
 983                 .ctl_name       = KERN_SETUID_DUMPABLE,
 984                 .procname       = "suid_dumpable",
 985                 .data           = &suid_dumpable,
 986                 .maxlen         = sizeof(int),
 987                 .mode           = 0644,
 988                 .proc_handler   = &proc_dointvec,
 989         },
 990         { .ctl_name = 0 }
 991 };
 992
 993 static ctl_table debug_table[] = {
 994         { .ctl_name = 0 }
 995 };
 996
 997 static ctl_table dev_table[] = {
 998         { .ctl_name = 0 }
 999 };
1000
1001 extern void init_irq_proc (void);
1002
1003 static DEFINE_SPINLOCK(sysctl_lock);
1004
1005 /* called under sysctl_lock */
1006 static int use_table(struct ctl_table_header *p)
1007 {
1008         if (unlikely(p->unregistering))
1009                 return 0;
1010         p->used++;
1011         return 1;
1012 }
1013
1014 /* called under sysctl_lock */
1015 static void unuse_table(struct ctl_table_header *p)
1016 {
1017         if (!--p->used)
1018                 if (unlikely(p->unregistering))
1019                         complete(p->unregistering);
1020 }
1021
1022 /* called under sysctl_lock, will reacquire if has to wait */
1023 static void start_unregistering(struct ctl_table_header *p)
1024 {
1025         /*
1026          * if p->used is 0, nobody will ever touch that entry again;
1027          * we'll eliminate all paths to it before dropping sysctl_lock
1028          */
1029         if (unlikely(p->used)) {
1030                 struct completion wait;
1031                 init_completion(&wait);
1032                 p->unregistering = &wait;
1033                 spin_unlock(&sysctl_lock);
1034                 wait_for_completion(&wait);
1035                 spin_lock(&sysctl_lock);
1036         }
1037         /*
1038          * do not remove from the list until nobody holds it; walking the
1039          * list in do_sysctl() relies on that.
1040          */
1041         list_del_init(&p->ctl_entry);
1042 }
1043
1044 void __init sysctl_init(void)
1045 {
1046 #ifdef CONFIG_PROC_FS
1047         register_proc_table(root_table, proc_sys_root, &root_table_header);
1048         init_irq_proc();
1049 #endif
1050 }
1051
1052 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1053                void __user *newval, size_t newlen)
1054 {
1055         struct list_head *tmp;
1056         int error = -ENOTDIR;
1057
1058         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1059                 return -ENOTDIR;
1060         if (oldval) {
1061                 int old_len;
1062                 if (!oldlenp || get_user(old_len, oldlenp))
1063                         return -EFAULT;
1064         }
1065         spin_lock(&sysctl_lock);
1066         tmp = &root_table_header.ctl_entry;
1067         do {
1068                 struct ctl_table_header *head =
1069                         list_entry(tmp, struct ctl_table_header, ctl_entry);
1070                 void *context = NULL;
1071
1072                 if (!use_table(head))
1073                         continue;
1074
1075                 spin_unlock(&sysctl_lock);
1076
1077                 error = parse_table(name, nlen, oldval, oldlenp,
1078                                         newval, newlen, head->ctl_table,
1079                                         &context);
1080                 kfree(context);
1081
1082                 spin_lock(&sysctl_lock);
1083                 unuse_table(head);
1084                 if (error != -ENOTDIR)
1085                         break;
1086         } while ((tmp = tmp->next) != &root_table_header.ctl_entry);
1087         spin_unlock(&sysctl_lock);
1088         return error;
1089 }
1090
1091 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1092 {
1093         struct __sysctl_args tmp;
1094         int error;
1095
1096         if (copy_from_user(&tmp, args, sizeof(tmp)))
1097                 return -EFAULT;
1098
1099         lock_kernel();
1100         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1101                           tmp.newval, tmp.newlen);
1102         unlock_kernel();
1103         return error;
1104 }
1105
1106 /*
1107  * ctl_perm does NOT grant the superuser all rights automatically, because
1108  * some sysctl variables are readonly even to root.
1109  */
1110
1111 static int test_perm(int mode, int op)
1112 {
1113         if (!current->euid)
1114                 mode >>= 6;
1115         else if (in_egroup_p(0))
1116                 mode >>= 3;
1117         if ((mode & op & 0007) == op)
1118                 return 0;
1119         return -EACCES;
1120 }
1121
1122 static inline int ctl_perm(ctl_table *table, int op)
1123 {
1124         int error;
1125         error = security_sysctl(table, op);
1126         if (error)
1127                 return error;
1128         return test_perm(table->mode, op);
1129 }
1130
1131 static int parse_table(int __user *name, int nlen,
1132                        void __user *oldval, size_t __user *oldlenp,
1133                        void __user *newval, size_t newlen,
1134                        ctl_table *table, void **context)
1135 {
1136         int n;
1137 repeat:
1138         if (!nlen)
1139                 return -ENOTDIR;
1140         if (get_user(n, name))
1141                 return -EFAULT;
1142         for ( ; table->ctl_name; table++) {
1143                 if (n == table->ctl_name || table->ctl_name == CTL_ANY) {
1144                         int error;
1145                         if (table->child) {
1146                                 if (ctl_perm(table, 001))
1147                                         return -EPERM;
1148                                 if (table->strategy) {
1149                                         error = table->strategy(
1150                                                 table, name, nlen,
1151                                                 oldval, oldlenp,
1152                                                 newval, newlen, context);
1153                                         if (error)
1154                                                 return error;
1155                                 }
1156                                 name++;
1157                                 nlen--;
1158                                 table = table->child;
1159                                 goto repeat;
1160                         }
1161                         error = do_sysctl_strategy(table, name, nlen,
1162                                                    oldval, oldlenp,
1163                                                    newval, newlen, context);
1164                         return error;
1165                 }
1166         }
1167         return -ENOTDIR;
1168 }
1169
1170 /* Perform the actual read/write of a sysctl table entry. */
1171 int do_sysctl_strategy (ctl_table *table,
1172                         int __user *name, int nlen,
1173                         void __user *oldval, size_t __user *oldlenp,
1174                         void __user *newval, size_t newlen, void **context)
1175 {
1176         int op = 0, rc;
1177         size_t len;
1178
1179         if (oldval)
1180                 op |= 004;
1181         if (newval)
1182                 op |= 002;
1183         if (ctl_perm(table, op))
1184                 return -EPERM;
1185
1186         if (table->strategy) {
1187                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1188                                      newval, newlen, context);
1189                 if (rc < 0)
1190                         return rc;
1191                 if (rc > 0)
1192                         return 0;
1193         }
1194
1195         /* If there is no strategy routine, or if the strategy returns
1196          * zero, proceed with automatic r/w */
1197         if (table->data && table->maxlen) {
1198                 if (oldval && oldlenp) {
1199                         if (get_user(len, oldlenp))
1200                                 return -EFAULT;
1201                         if (len) {
1202                                 if (len > table->maxlen)
1203                                         len = table->maxlen;
1204                                 if(copy_to_user(oldval, table->data, len))
1205                                         return -EFAULT;
1206                                 if(put_user(len, oldlenp))
1207                                         return -EFAULT;
1208                         }
1209                 }
1210                 if (newval && newlen) {
1211                         len = newlen;
1212                         if (len > table->maxlen)
1213                                 len = table->maxlen;
1214                         if(copy_from_user(table->data, newval, len))
1215                                 return -EFAULT;
1216                 }
1217         }
1218         return 0;
1219 }
1220
1221 /**
1222  * register_sysctl_table - register a sysctl hierarchy
1223  * @table: the top-level table structure
1224  * @insert_at_head: whether the entry should be inserted in front or at the end
1225  *
1226  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1227  * array. An entry with a ctl_name of 0 terminates the table.
1228  *
1229  * The members of the &ctl_table structure are used as follows:
1230  *
1231  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1232  *            must be unique within that level of sysctl
1233  *
1234  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1235  *            enter a sysctl file
1236  *
1237  * data - a pointer to data for use by proc_handler
1238  *
1239  * maxlen - the maximum size in bytes of the data
1240  *
1241  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1242  *
1243  * child - a pointer to the child sysctl table if this entry is a directory, or
1244  *         %NULL.
1245  *
1246  * proc_handler - the text handler routine (described below)
1247  *
1248  * strategy - the strategy routine (described below)
1249  *
1250  * de - for internal use by the sysctl routines
1251  *
1252  * extra1, extra2 - extra pointers usable by the proc handler routines
1253  *
1254  * Leaf nodes in the sysctl tree will be represented by a single file
1255  * under /proc; non-leaf nodes will be represented by directories.
1256  *
1257  * sysctl(2) can automatically manage read and write requests through
1258  * the sysctl table.  The data and maxlen fields of the ctl_table
1259  * struct enable minimal validation of the values being written to be
1260  * performed, and the mode field allows minimal authentication.
1261  *
1262  * More sophisticated management can be enabled by the provision of a
1263  * strategy routine with the table entry.  This will be called before
1264  * any automatic read or write of the data is performed.
1265  *
1266  * The strategy routine may return
1267  *
1268  * < 0 - Error occurred (error is passed to user process)
1269  *
1270  * 0   - OK - proceed with automatic read or write.
1271  *
1272  * > 0 - OK - read or write has been done by the strategy routine, so
1273  *       return immediately.
1274  *
1275  * There must be a proc_handler routine for any terminal nodes
1276  * mirrored under /proc/sys (non-terminals are handled by a built-in
1277  * directory handler).  Several default handlers are available to
1278  * cover common cases -
1279  *
1280  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1281  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1282  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1283  *
1284  * It is the handler's job to read the input buffer from user memory
1285  * and process it. The handler should return 0 on success.
1286  *
1287  * This routine returns %NULL on a failure to register, and a pointer
1288  * to the table header on success.
1289  */
1290 struct ctl_table_header *register_sysctl_table(ctl_table * table,
1291                                                int insert_at_head)
1292 {
1293         struct ctl_table_header *tmp;
1294         tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1295         if (!tmp)
1296                 return NULL;
1297         tmp->ctl_table = table;
1298         INIT_LIST_HEAD(&tmp->ctl_entry);
1299         tmp->used = 0;
1300         tmp->unregistering = NULL;
1301         spin_lock(&sysctl_lock);
1302         if (insert_at_head)
1303                 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
1304         else
1305                 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1306         spin_unlock(&sysctl_lock);
1307 #ifdef CONFIG_PROC_FS
1308         register_proc_table(table, proc_sys_root, tmp);
1309 #endif
1310         return tmp;
1311 }
1312
1313 /**
1314  * unregister_sysctl_table - unregister a sysctl table hierarchy
1315  * @header: the header returned from register_sysctl_table
1316  *
1317  * Unregisters the sysctl table and all children. proc entries may not
1318  * actually be removed until they are no longer used by anyone.
1319  */
1320 void unregister_sysctl_table(struct ctl_table_header * header)
1321 {
1322         might_sleep();
1323         spin_lock(&sysctl_lock);
1324         start_unregistering(header);
1325 #ifdef CONFIG_PROC_FS
1326         unregister_proc_table(header->ctl_table, proc_sys_root);
1327 #endif
1328         spin_unlock(&sysctl_lock);
1329         kfree(header);
1330 }
1331
1332 /*
1333  * /proc/sys support
1334  */
1335
1336 #ifdef CONFIG_PROC_FS
1337
1338 /* Scan the sysctl entries in table and add them all into /proc */
1339 static void register_proc_table(ctl_table * table, struct proc_dir_entry *root, void *set)
1340 {
1341         struct proc_dir_entry *de;
1342         int len;
1343         mode_t mode;
1344
1345         for (; table->ctl_name; table++) {
1346                 /* Can't do anything without a proc name. */
1347                 if (!table->procname)
1348                         continue;
1349                 /* Maybe we can't do anything with it... */
1350                 if (!table->proc_handler && !table->child) {
1351                         printk(KERN_WARNING "SYSCTL: Can't register %s\n",
1352                                 table->procname);
1353                         continue;
1354                 }
1355
1356                 len = strlen(table->procname);
1357                 mode = table->mode;
1358
1359                 de = NULL;
1360                 if (table->proc_handler)
1361                         mode |= S_IFREG;
1362                 else {
1363                         mode |= S_IFDIR;
1364                         for (de = root->subdir; de; de = de->next) {
1365                                 if (proc_match(len, table->procname, de))
1366                                         break;
1367                         }
1368                         /* If the subdir exists already, de is non-NULL */
1369                 }
1370
1371                 if (!de) {
1372                         de = create_proc_entry(table->procname, mode, root);
1373                         if (!de)
1374                                 continue;
1375                         de->set = set;
1376                         de->data = (void *) table;
1377                         if (table->proc_handler)
1378                                 de->proc_fops = &proc_sys_file_operations;
1379                 }
1380                 table->de = de;
1381                 if (de->mode & S_IFDIR)
1382                         register_proc_table(table->child, de, set);
1383         }
1384 }
1385
1386 /*
1387  * Unregister a /proc sysctl table and any subdirectories.
1388  */
1389 static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
1390 {
1391         struct proc_dir_entry *de;
1392         for (; table->ctl_name; table++) {
1393                 if (!(de = table->de))
1394                         continue;
1395                 if (de->mode & S_IFDIR) {
1396                         if (!table->child) {
1397                                 printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
1398                                 continue;
1399                         }
1400                         unregister_proc_table(table->child, de);
1401
1402                         /* Don't unregister directories which still have entries.. */
1403                         if (de->subdir)
1404                                 continue;
1405                 }
1406
1407                 /*
1408                  * In any case, mark the entry as goner; we'll keep it
1409                  * around if it's busy, but we'll know to do nothing with
1410                  * its fields.  We are under sysctl_lock here.
1411                  */
1412                 de->data = NULL;
1413
1414                 /* Don't unregister proc entries that are still being used.. */
1415                 if (atomic_read(&de->count))
1416                         continue;
1417
1418                 table->de = NULL;
1419                 remove_proc_entry(table->procname, root);
1420         }
1421 }
1422
1423 static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
1424                           size_t count, loff_t *ppos)
1425 {
1426         int op;
1427         struct proc_dir_entry *de = PDE(file->f_dentry->d_inode);
1428         struct ctl_table *table;
1429         size_t res;
1430         ssize_t error = -ENOTDIR;
1431
1432         spin_lock(&sysctl_lock);
1433         if (de && de->data && use_table(de->set)) {
1434                 /*
1435                  * at that point we know that sysctl was not unregistered
1436                  * and won't be until we finish
1437                  */
1438                 spin_unlock(&sysctl_lock);
1439                 table = (struct ctl_table *) de->data;
1440                 if (!table || !table->proc_handler)
1441                         goto out;
1442                 error = -EPERM;
1443                 op = (write ? 002 : 004);
1444                 if (ctl_perm(table, op))
1445                         goto out;
1446
1447                 /* careful: calling conventions are nasty here */
1448                 res = count;
1449                 error = (*table->proc_handler)(table, write, file,
1450                                                 buf, &res, ppos);
1451                 if (!error)
1452                         error = res;
1453         out:
1454                 spin_lock(&sysctl_lock);
1455                 unuse_table(de->set);
1456         }
1457         spin_unlock(&sysctl_lock);
1458         return error;
1459 }
1460
1461 static int proc_opensys(struct inode *inode, struct file *file)
1462 {
1463         if (file->f_mode & FMODE_WRITE) {
1464                 /*
1465                  * sysctl entries that are not writable,
1466                  * are _NOT_ writable, capabilities or not.
1467                  */
1468                 if (!(inode->i_mode & S_IWUSR))
1469                         return -EPERM;
1470         }
1471
1472         return 0;
1473 }
1474
1475 static ssize_t proc_readsys(struct file * file, char __user * buf,
1476                             size_t count, loff_t *ppos)
1477 {
1478         return do_rw_proc(0, file, buf, count, ppos);
1479 }
1480
1481 static ssize_t proc_writesys(struct file * file, const char __user * buf,
1482                              size_t count, loff_t *ppos)
1483 {
1484         return do_rw_proc(1, file, (char __user *) buf, count, ppos);
1485 }
1486
1487 /**
1488  * proc_dostring - read a string sysctl
1489  * @table: the sysctl table
1490  * @write: %TRUE if this is a write to the sysctl file
1491  * @filp: the file structure
1492  * @buffer: the user buffer
1493  * @lenp: the size of the user buffer
1494  * @ppos: file position
1495  *
1496  * Reads/writes a string from/to the user buffer. If the kernel
1497  * buffer provided is not large enough to hold the string, the
1498  * string is truncated. The copied string is %NULL-terminated.
1499  * If the string is being read by the user process, it is copied
1500  * and a newline '\n' is added. It is truncated if the buffer is
1501  * not large enough.
1502  *
1503  * Returns 0 on success.
1504  */
1505 int proc_dostring(ctl_table *table, int write, struct file *filp,
1506                   void __user *buffer, size_t *lenp, loff_t *ppos)
1507 {
1508         size_t len;
1509         char __user *p;
1510         char c;
1511
1512         if (!table->data || !table->maxlen || !*lenp ||
1513             (*ppos && !write)) {
1514                 *lenp = 0;
1515                 return 0;
1516         }
1517
1518         if (write) {
1519                 len = 0;
1520                 p = buffer;
1521                 while (len < *lenp) {
1522                         if (get_user(c, p++))
1523                                 return -EFAULT;
1524                         if (c == 0 || c == '\n')
1525                                 break;
1526                         len++;
1527                 }
1528                 if (len >= table->maxlen)
1529                         len = table->maxlen-1;
1530                 if(copy_from_user(table->data, buffer, len))
1531                         return -EFAULT;
1532                 ((char *) table->data)[len] = 0;
1533                 *ppos += *lenp;
1534         } else {
1535                 len = strlen(table->data);
1536                 if (len > table->maxlen)
1537                         len = table->maxlen;
1538                 if (len > *lenp)
1539                         len = *lenp;
1540                 if (len)
1541                         if(copy_to_user(buffer, table->data, len))
1542                                 return -EFAULT;
1543                 if (len < *lenp) {
1544                         if(put_user('\n', ((char __user *) buffer) + len))
1545                                 return -EFAULT;
1546                         len++;
1547                 }
1548                 *lenp = len;
1549                 *ppos += len;
1550         }
1551         return 0;
1552 }
1553
1554 /*
1555  *      Special case of dostring for the UTS structure. This has locks
1556  *      to observe. Should this be in kernel/sys.c ????
1557  */
1558
1559 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
1560                   void __user *buffer, size_t *lenp, loff_t *ppos)
1561 {
1562         int r;
1563
1564         if (!write) {
1565                 down_read(&uts_sem);
1566                 r=proc_dostring(table,0,filp,buffer,lenp, ppos);
1567                 up_read(&uts_sem);
1568         } else {
1569                 down_write(&uts_sem);
1570                 r=proc_dostring(table,1,filp,buffer,lenp, ppos);
1571                 up_write(&uts_sem);
1572         }
1573         return r;
1574 }
1575
1576 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1577                                  int *valp,
1578                                  int write, void *data)
1579 {
1580         if (write) {
1581                 *valp = *negp ? -*lvalp : *lvalp;
1582         } else {
1583                 int val = *valp;
1584                 if (val < 0) {
1585                         *negp = -1;
1586                         *lvalp = (unsigned long)-val;
1587                 } else {
1588                         *negp = 0;
1589                         *lvalp = (unsigned long)val;
1590                 }
1591         }
1592         return 0;
1593 }
1594
1595 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1596                   void __user *buffer, size_t *lenp, loff_t *ppos,
1597                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1598                               int write, void *data),
1599                   void *data)
1600 {
1601 #define TMPBUFLEN 21
1602         int *i, vleft, first=1, neg, val;
1603         unsigned long lval;
1604         size_t left, len;
1605
1606         char buf[TMPBUFLEN], *p;
1607         char __user *s = buffer;
1608
1609         if (!table->data || !table->maxlen || !*lenp ||
1610             (*ppos && !write)) {
1611                 *lenp = 0;
1612                 return 0;
1613         }
1614
1615         i = (int *) table->data;
1616         vleft = table->maxlen / sizeof(*i);
1617         left = *lenp;
1618
1619         if (!conv)
1620                 conv = do_proc_dointvec_conv;
1621
1622         for (; left && vleft--; i++, first=0) {
1623                 if (write) {
1624                         while (left) {
1625                                 char c;
1626                                 if (get_user(c, s))
1627                                         return -EFAULT;
1628                                 if (!isspace(c))
1629                                         break;
1630                                 left--;
1631                                 s++;
1632                         }
1633                         if (!left)
1634                                 break;
1635                         neg = 0;
1636                         len = left;
1637                         if (len > sizeof(buf) - 1)
1638                                 len = sizeof(buf) - 1;
1639                         if (copy_from_user(buf, s, len))
1640                                 return -EFAULT;
1641                         buf[len] = 0;
1642                         p = buf;
1643                         if (*p == '-' && left > 1) {
1644                                 neg = 1;
1645                                 left--, p++;
1646                         }
1647                         if (*p < '0' || *p > '9')
1648                                 break;
1649
1650                         lval = simple_strtoul(p, &p, 0);
1651
1652                         len = p-buf;
1653                         if ((len < left) && *p && !isspace(*p))
1654                                 break;
1655                         if (neg)
1656                                 val = -val;
1657                         s += len;
1658                         left -= len;
1659
1660                         if (conv(&neg, &lval, i, 1, data))
1661                                 break;
1662                 } else {
1663                         p = buf;
1664                         if (!first)
1665                                 *p++ = '\t';
1666
1667                         if (conv(&neg, &lval, i, 0, data))
1668                                 break;
1669
1670                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
1671                         len = strlen(buf);
1672                         if (len > left)
1673                                 len = left;
1674                         if(copy_to_user(s, buf, len))
1675                                 return -EFAULT;
1676                         left -= len;
1677                         s += len;
1678                 }
1679         }
1680
1681         if (!write && !first && left) {
1682                 if(put_user('\n', s))
1683                         return -EFAULT;
1684                 left--, s++;
1685         }
1686         if (write) {
1687                 while (left) {
1688                         char c;
1689                         if (get_user(c, s++))
1690                                 return -EFAULT;
1691                         if (!isspace(c))
1692                                 break;
1693                         left--;
1694                 }
1695         }
1696         if (write && first)
1697                 return -EINVAL;
1698         *lenp -= left;
1699         *ppos += *lenp;
1700         return 0;
1701 #undef TMPBUFLEN
1702 }
1703
1704 /**
1705  * proc_dointvec - read a vector of integers
1706  * @table: the sysctl table
1707  * @write: %TRUE if this is a write to the sysctl file
1708  * @filp: the file structure
1709  * @buffer: the user buffer
1710  * @lenp: the size of the user buffer
1711  * @ppos: file position
1712  *
1713  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1714  * values from/to the user buffer, treated as an ASCII string.
1715  *
1716  * Returns 0 on success.
1717  */
1718 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1719                      void __user *buffer, size_t *lenp, loff_t *ppos)
1720 {
1721     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1722                             NULL,NULL);
1723 }
1724
1725 #define OP_SET  0
1726 #define OP_AND  1
1727 #define OP_OR   2
1728 #define OP_MAX  3
1729 #define OP_MIN  4
1730
1731 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1732                                       int *valp,
1733                                       int write, void *data)
1734 {
1735         int op = *(int *)data;
1736         if (write) {
1737                 int val = *negp ? -*lvalp : *lvalp;
1738                 switch(op) {
1739                 case OP_SET:    *valp = val; break;
1740                 case OP_AND:    *valp &= val; break;
1741                 case OP_OR:     *valp |= val; break;
1742                 case OP_MAX:    if(*valp < val)
1743                                         *valp = val;
1744                                 break;
1745                 case OP_MIN:    if(*valp > val)
1746                                 *valp = val;
1747                                 break;
1748                 }
1749         } else {
1750                 int val = *valp;
1751                 if (val < 0) {
1752                         *negp = -1;
1753                         *lvalp = (unsigned long)-val;
1754                 } else {
1755                         *negp = 0;
1756                         *lvalp = (unsigned long)val;
1757                 }
1758         }
1759         return 0;
1760 }
1761
1762 /*
1763  *      init may raise the set.
1764  */
1765
1766 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1767                         void __user *buffer, size_t *lenp, loff_t *ppos)
1768 {
1769         int op;
1770
1771         if (!capable(CAP_SYS_MODULE)) {
1772                 return -EPERM;
1773         }
1774
1775         op = (current->pid == 1) ? OP_SET : OP_AND;
1776         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1777                                 do_proc_dointvec_bset_conv,&op);
1778 }
1779
1780 struct do_proc_dointvec_minmax_conv_param {
1781         int *min;
1782         int *max;
1783 };
1784
1785 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1786                                         int *valp,
1787                                         int write, void *data)
1788 {
1789         struct do_proc_dointvec_minmax_conv_param *param = data;
1790         if (write) {
1791                 int val = *negp ? -*lvalp : *lvalp;
1792                 if ((param->min && *param->min > val) ||
1793                     (param->max && *param->max < val))
1794                         return -EINVAL;
1795                 *valp = val;
1796         } else {
1797                 int val = *valp;
1798                 if (val < 0) {
1799                         *negp = -1;
1800                         *lvalp = (unsigned long)-val;
1801                 } else {
1802                         *negp = 0;
1803                         *lvalp = (unsigned long)val;
1804                 }
1805         }
1806         return 0;
1807 }
1808
1809 /**
1810  * proc_dointvec_minmax - read a vector of integers with min/max values
1811  * @table: the sysctl table
1812  * @write: %TRUE if this is a write to the sysctl file
1813  * @filp: the file structure
1814  * @buffer: the user buffer
1815  * @lenp: the size of the user buffer
1816  * @ppos: file position
1817  *
1818  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1819  * values from/to the user buffer, treated as an ASCII string.
1820  *
1821  * This routine will ensure the values are within the range specified by
1822  * table->extra1 (min) and table->extra2 (max).
1823  *
1824  * Returns 0 on success.
1825  */
1826 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1827                   void __user *buffer, size_t *lenp, loff_t *ppos)
1828 {
1829         struct do_proc_dointvec_minmax_conv_param param = {
1830                 .min = (int *) table->extra1,
1831                 .max = (int *) table->extra2,
1832         };
1833         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1834                                 do_proc_dointvec_minmax_conv, &param);
1835 }
1836
1837 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1838                                      struct file *filp,
1839                                      void __user *buffer,
1840                                      size_t *lenp, loff_t *ppos,
1841                                      unsigned long convmul,
1842                                      unsigned long convdiv)
1843 {
1844 #define TMPBUFLEN 21
1845         unsigned long *i, *min, *max, val;
1846         int vleft, first=1, neg;
1847         size_t len, left;
1848         char buf[TMPBUFLEN], *p;
1849         char __user *s = buffer;
1850
1851         if (!table->data || !table->maxlen || !*lenp ||
1852             (*ppos && !write)) {
1853                 *lenp = 0;
1854                 return 0;
1855         }
1856
1857         i = (unsigned long *) table->data;
1858         min = (unsigned long *) table->extra1;
1859         max = (unsigned long *) table->extra2;
1860         vleft = table->maxlen / sizeof(unsigned long);
1861         left = *lenp;
1862
1863         for (; left && vleft--; i++, min++, max++, first=0) {
1864                 if (write) {
1865                         while (left) {
1866                                 char c;
1867                                 if (get_user(c, s))
1868                                         return -EFAULT;
1869                                 if (!isspace(c))
1870                                         break;
1871                                 left--;
1872                                 s++;
1873                         }
1874                         if (!left)
1875                                 break;
1876                         neg = 0;
1877                         len = left;
1878                         if (len > TMPBUFLEN-1)
1879                                 len = TMPBUFLEN-1;
1880                         if (copy_from_user(buf, s, len))
1881                                 return -EFAULT;
1882                         buf[len] = 0;
1883                         p = buf;
1884                         if (*p == '-' && left > 1) {
1885                                 neg = 1;
1886                                 left--, p++;
1887                         }
1888                         if (*p < '0' || *p > '9')
1889                                 break;
1890                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1891                         len = p-buf;
1892                         if ((len < left) && *p && !isspace(*p))
1893                                 break;
1894                         if (neg)
1895                                 val = -val;
1896                         s += len;
1897                         left -= len;
1898
1899                         if(neg)
1900                                 continue;
1901                         if ((min && val < *min) || (max && val > *max))
1902                                 continue;
1903                         *i = val;
1904                 } else {
1905                         p = buf;
1906                         if (!first)
1907                                 *p++ = '\t';
1908                         sprintf(p, "%lu", convdiv * (*i) / convmul);
1909                         len = strlen(buf);
1910                         if (len > left)
1911                                 len = left;
1912                         if(copy_to_user(s, buf, len))
1913                                 return -EFAULT;
1914                         left -= len;
1915                         s += len;
1916                 }
1917         }
1918
1919         if (!write && !first && left) {
1920                 if(put_user('\n', s))
1921                         return -EFAULT;
1922                 left--, s++;
1923         }
1924         if (write) {
1925                 while (left) {
1926                         char c;
1927                         if (get_user(c, s++))
1928                                 return -EFAULT;
1929                         if (!isspace(c))
1930                                 break;
1931                         left--;
1932                 }
1933         }
1934         if (write && first)
1935                 return -EINVAL;
1936         *lenp -= left;
1937         *ppos += *lenp;
1938         return 0;
1939 #undef TMPBUFLEN
1940 }
1941
1942 /**
1943  * proc_doulongvec_minmax - read a vector of long integers with min/max values
1944  * @table: the sysctl table
1945  * @write: %TRUE if this is a write to the sysctl file
1946  * @filp: the file structure
1947  * @buffer: the user buffer
1948  * @lenp: the size of the user buffer
1949  * @ppos: file position
1950  *
1951  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1952  * values from/to the user buffer, treated as an ASCII string.
1953  *
1954  * This routine will ensure the values are within the range specified by
1955  * table->extra1 (min) and table->extra2 (max).
1956  *
1957  * Returns 0 on success.
1958  */
1959 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
1960                            void __user *buffer, size_t *lenp, loff_t *ppos)
1961 {
1962     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
1963 }
1964
1965 /**
1966  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
1967  * @table: the sysctl table
1968  * @write: %TRUE if this is a write to the sysctl file
1969  * @filp: the file structure
1970  * @buffer: the user buffer
1971  * @lenp: the size of the user buffer
1972  * @ppos: file position
1973  *
1974  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1975  * values from/to the user buffer, treated as an ASCII string. The values
1976  * are treated as milliseconds, and converted to jiffies when they are stored.
1977  *
1978  * This routine will ensure the values are within the range specified by
1979  * table->extra1 (min) and table->extra2 (max).
1980  *
1981  * Returns 0 on success.
1982  */
1983 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
1984                                       struct file *filp,
1985                                       void __user *buffer,
1986                                       size_t *lenp, loff_t *ppos)
1987 {
1988     return do_proc_doulongvec_minmax(table, write, filp, buffer,
1989                                      lenp, ppos, HZ, 1000l);
1990 }
1991
1992
1993 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
1994                                          int *valp,
1995                                          int write, void *data)
1996 {
1997         if (write) {
1998                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
1999         } else {
2000                 int val = *valp;
2001                 unsigned long lval;
2002                 if (val < 0) {
2003                         *negp = -1;
2004                         lval = (unsigned long)-val;
2005                 } else {
2006                         *negp = 0;
2007                         lval = (unsigned long)val;
2008                 }
2009                 *lvalp = lval / HZ;
2010         }
2011         return 0;
2012 }
2013
2014 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2015                                                 int *valp,
2016                                                 int write, void *data)
2017 {
2018         if (write) {
2019                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2020         } else {
2021                 int val = *valp;
2022                 unsigned long lval;
2023                 if (val < 0) {
2024                         *negp = -1;
2025                         lval = (unsigned long)-val;
2026                 } else {
2027                         *negp = 0;
2028                         lval = (unsigned long)val;
2029                 }
2030                 *lvalp = jiffies_to_clock_t(lval);
2031         }
2032         return 0;
2033 }
2034
2035 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2036                                             int *valp,
2037                                             int write, void *data)
2038 {
2039         if (write) {
2040                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2041         } else {
2042                 int val = *valp;
2043                 unsigned long lval;
2044                 if (val < 0) {
2045                         *negp = -1;
2046                         lval = (unsigned long)-val;
2047                 } else {
2048                         *negp = 0;
2049                         lval = (unsigned long)val;
2050                 }
2051                 *lvalp = jiffies_to_msecs(lval);
2052         }
2053         return 0;
2054 }
2055
2056 /**
2057  * proc_dointvec_jiffies - read a vector of integers as seconds
2058  * @table: the sysctl table
2059  * @write: %TRUE if this is a write to the sysctl file
2060  * @filp: the file structure
2061  * @buffer: the user buffer
2062  * @lenp: the size of the user buffer
2063  * @ppos: file position
2064  *
2065  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2066  * values from/to the user buffer, treated as an ASCII string.
2067  * The values read are assumed to be in seconds, and are converted into
2068  * jiffies.
2069  *
2070  * Returns 0 on success.
2071  */
2072 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2073                           void __user *buffer, size_t *lenp, loff_t *ppos)
2074 {
2075     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2076                             do_proc_dointvec_jiffies_conv,NULL);
2077 }
2078
2079 /**
2080  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2081  * @table: the sysctl table
2082  * @write: %TRUE if this is a write to the sysctl file
2083  * @filp: the file structure
2084  * @buffer: the user buffer
2085  * @lenp: the size of the user buffer
2086  * @ppos: pointer to the file position
2087  *
2088  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2089  * values from/to the user buffer, treated as an ASCII string.
2090  * The values read are assumed to be in 1/USER_HZ seconds, and
2091  * are converted into jiffies.
2092  *
2093  * Returns 0 on success.
2094  */
2095 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2096                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2097 {
2098     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2099                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2100 }
2101
2102 /**
2103  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2104  * @table: the sysctl table
2105  * @write: %TRUE if this is a write to the sysctl file
2106  * @filp: the file structure
2107  * @buffer: the user buffer
2108  * @lenp: the size of the user buffer
2109  * @ppos: file position
2110  * @ppos: the current position in the file
2111  *
2112  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2113  * values from/to the user buffer, treated as an ASCII string.
2114  * The values read are assumed to be in 1/1000 seconds, and
2115  * are converted into jiffies.
2116  *
2117  * Returns 0 on success.
2118  */
2119 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2120                              void __user *buffer, size_t *lenp, loff_t *ppos)
2121 {
2122         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2123                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2124 }
2125
2126 #else /* CONFIG_PROC_FS */
2127
2128 int proc_dostring(ctl_table *table, int write, struct file *filp,
2129                   void __user *buffer, size_t *lenp, loff_t *ppos)
2130 {
2131         return -ENOSYS;
2132 }
2133
2134 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
2135                             void __user *buffer, size_t *lenp, loff_t *ppos)
2136 {
2137         return -ENOSYS;
2138 }
2139
2140 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2141                   void __user *buffer, size_t *lenp, loff_t *ppos)
2142 {
2143         return -ENOSYS;
2144 }
2145
2146 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2147                         void __user *buffer, size_t *lenp, loff_t *ppos)
2148 {
2149         return -ENOSYS;
2150 }
2151
2152 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2153                     void __user *buffer, size_t *lenp, loff_t *ppos)
2154 {
2155         return -ENOSYS;
2156 }
2157
2158 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2159                     void __user *buffer, size_t *lenp, loff_t *ppos)
2160 {
2161         return -ENOSYS;
2162 }
2163
2164 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2165                     void __user *buffer, size_t *lenp, loff_t *ppos)
2166 {
2167         return -ENOSYS;
2168 }
2169
2170 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2171                              void __user *buffer, size_t *lenp, loff_t *ppos)
2172 {
2173         return -ENOSYS;
2174 }
2175
2176 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2177                     void __user *buffer, size_t *lenp, loff_t *ppos)
2178 {
2179         return -ENOSYS;
2180 }
2181
2182 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2183                                       struct file *filp,
2184                                       void __user *buffer,
2185                                       size_t *lenp, loff_t *ppos)
2186 {
2187     return -ENOSYS;
2188 }
2189
2190
2191 #endif /* CONFIG_PROC_FS */
2192
2193
2194 /*
2195  * General sysctl support routines
2196  */
2197
2198 /* The generic string strategy routine: */
2199 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2200                   void __user *oldval, size_t __user *oldlenp,
2201                   void __user *newval, size_t newlen, void **context)
2202 {
2203         if (!table->data || !table->maxlen)
2204                 return -ENOTDIR;
2205
2206         if (oldval && oldlenp) {
2207                 size_t bufsize;
2208                 if (get_user(bufsize, oldlenp))
2209                         return -EFAULT;
2210                 if (bufsize) {
2211                         size_t len = strlen(table->data), copied;
2212
2213                         /* This shouldn't trigger for a well-formed sysctl */
2214                         if (len > table->maxlen)
2215                                 len = table->maxlen;
2216
2217                         /* Copy up to a max of bufsize-1 bytes of the string */
2218                         copied = (len >= bufsize) ? bufsize - 1 : len;
2219
2220                         if (copy_to_user(oldval, table->data, copied) ||
2221                             put_user(0, (char __user *)(oldval + copied)))
2222                                 return -EFAULT;
2223                         if (put_user(len, oldlenp))
2224                                 return -EFAULT;
2225                 }
2226         }
2227         if (newval && newlen) {
2228                 size_t len = newlen;
2229                 if (len > table->maxlen)
2230                         len = table->maxlen;
2231                 if(copy_from_user(table->data, newval, len))
2232                         return -EFAULT;
2233                 if (len == table->maxlen)
2234                         len--;
2235                 ((char *) table->data)[len] = 0;
2236         }
2237         return 1;
2238 }
2239
2240 /*
2241  * This function makes sure that all of the integers in the vector
2242  * are between the minimum and maximum values given in the arrays
2243  * table->extra1 and table->extra2, respectively.
2244  */
2245 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2246                 void __user *oldval, size_t __user *oldlenp,
2247                 void __user *newval, size_t newlen, void **context)
2248 {
2249
2250         if (newval && newlen) {
2251                 int __user *vec = (int __user *) newval;
2252                 int *min = (int *) table->extra1;
2253                 int *max = (int *) table->extra2;
2254                 size_t length;
2255                 int i;
2256
2257                 if (newlen % sizeof(int) != 0)
2258                         return -EINVAL;
2259
2260                 if (!table->extra1 && !table->extra2)
2261                         return 0;
2262
2263                 if (newlen > table->maxlen)
2264                         newlen = table->maxlen;
2265                 length = newlen / sizeof(int);
2266
2267                 for (i = 0; i < length; i++) {
2268                         int value;
2269                         if (get_user(value, vec + i))
2270                                 return -EFAULT;
2271                         if (min && value < min[i])
2272                                 return -EINVAL;
2273                         if (max && value > max[i])
2274                                 return -EINVAL;
2275                 }
2276         }
2277         return 0;
2278 }
2279
2280 /* Strategy function to convert jiffies to seconds */
2281 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2282                 void __user *oldval, size_t __user *oldlenp,
2283                 void __user *newval, size_t newlen, void **context)
2284 {
2285         if (oldval) {
2286                 size_t olen;
2287                 if (oldlenp) {
2288                         if (get_user(olen, oldlenp))
2289                                 return -EFAULT;
2290                         if (olen!=sizeof(int))
2291                                 return -EINVAL;
2292                 }
2293                 if (put_user(*(int *)(table->data)/HZ, (int __user *)oldval) ||
2294                     (oldlenp && put_user(sizeof(int),oldlenp)))
2295                         return -EFAULT;
2296         }
2297         if (newval && newlen) {
2298                 int new;
2299                 if (newlen != sizeof(int))
2300                         return -EINVAL;
2301                 if (get_user(new, (int __user *)newval))
2302                         return -EFAULT;
2303                 *(int *)(table->data) = new*HZ;
2304         }
2305         return 1;
2306 }
2307
2308 /* Strategy function to convert jiffies to seconds */
2309 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2310                 void __user *oldval, size_t __user *oldlenp,
2311                 void __user *newval, size_t newlen, void **context)
2312 {
2313         if (oldval) {
2314                 size_t olen;
2315                 if (oldlenp) {
2316                         if (get_user(olen, oldlenp))
2317                                 return -EFAULT;
2318                         if (olen!=sizeof(int))
2319                                 return -EINVAL;
2320                 }
2321                 if (put_user(jiffies_to_msecs(*(int *)(table->data)), (int __user *)oldval) ||
2322                     (oldlenp && put_user(sizeof(int),oldlenp)))
2323                         return -EFAULT;
2324         }
2325         if (newval && newlen) {
2326                 int new;
2327                 if (newlen != sizeof(int))
2328                         return -EINVAL;
2329                 if (get_user(new, (int __user *)newval))
2330                         return -EFAULT;
2331                 *(int *)(table->data) = msecs_to_jiffies(new);
2332         }
2333         return 1;
2334 }
2335
2336 #else /* CONFIG_SYSCTL */
2337
2338
2339 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2340 {
2341         return -ENOSYS;
2342 }
2343
2344 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2345                   void __user *oldval, size_t __user *oldlenp,
2346                   void __user *newval, size_t newlen, void **context)
2347 {
2348         return -ENOSYS;
2349 }
2350
2351 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2352                 void __user *oldval, size_t __user *oldlenp,
2353                 void __user *newval, size_t newlen, void **context)
2354 {
2355         return -ENOSYS;
2356 }
2357
2358 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2359                 void __user *oldval, size_t __user *oldlenp,
2360                 void __user *newval, size_t newlen, void **context)
2361 {
2362         return -ENOSYS;
2363 }
2364
2365 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2366                 void __user *oldval, size_t __user *oldlenp,
2367                 void __user *newval, size_t newlen, void **context)
2368 {
2369         return -ENOSYS;
2370 }
2371
2372 int proc_dostring(ctl_table *table, int write, struct file *filp,
2373                   void __user *buffer, size_t *lenp, loff_t *ppos)
2374 {
2375         return -ENOSYS;
2376 }
2377
2378 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2379                   void __user *buffer, size_t *lenp, loff_t *ppos)
2380 {
2381         return -ENOSYS;
2382 }
2383
2384 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2385                         void __user *buffer, size_t *lenp, loff_t *ppos)
2386 {
2387         return -ENOSYS;
2388 }
2389
2390 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2391                     void __user *buffer, size_t *lenp, loff_t *ppos)
2392 {
2393         return -ENOSYS;
2394 }
2395
2396 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2397                           void __user *buffer, size_t *lenp, loff_t *ppos)
2398 {
2399         return -ENOSYS;
2400 }
2401
2402 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2403                           void __user *buffer, size_t *lenp, loff_t *ppos)
2404 {
2405         return -ENOSYS;
2406 }
2407
2408 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2409                              void __user *buffer, size_t *lenp, loff_t *ppos)
2410 {
2411         return -ENOSYS;
2412 }
2413
2414 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2415                     void __user *buffer, size_t *lenp, loff_t *ppos)
2416 {
2417         return -ENOSYS;
2418 }
2419
2420 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2421                                       struct file *filp,
2422                                       void __user *buffer,
2423                                       size_t *lenp, loff_t *ppos)
2424 {
2425     return -ENOSYS;
2426 }
2427
2428 struct ctl_table_header * register_sysctl_table(ctl_table * table,
2429                                                 int insert_at_head)
2430 {
2431         return NULL;
2432 }
2433
2434 void unregister_sysctl_table(struct ctl_table_header * table)
2435 {
2436 }
2437
2438 #endif /* CONFIG_SYSCTL */
2439
2440 /*
2441  * No sense putting this after each symbol definition, twice,
2442  * exception granted :-)
2443  */
2444 EXPORT_SYMBOL(proc_dointvec);
2445 EXPORT_SYMBOL(proc_dointvec_jiffies);
2446 EXPORT_SYMBOL(proc_dointvec_minmax);
2447 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2448 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2449 EXPORT_SYMBOL(proc_dostring);
2450 EXPORT_SYMBOL(proc_doulongvec_minmax);
2451 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2452 EXPORT_SYMBOL(register_sysctl_table);
2453 EXPORT_SYMBOL(sysctl_intvec);
2454 EXPORT_SYMBOL(sysctl_jiffies);
2455 EXPORT_SYMBOL(sysctl_ms_jiffies);
2456 EXPORT_SYMBOL(sysctl_string);
2457 EXPORT_SYMBOL(unregister_sysctl_table);