kernel/sysctl.c

   1 /*
   2  * sysctl.c: General linux system control interface
   3  *
   4  * Begun 24 March 1995, Stephen Tweedie
   5  * Added /proc support, Dec 1995
   6  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
   7  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
   8  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
   9  * Dynamic registration fixes, Stephen Tweedie.
  10  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
  11  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
  12  *  Horn.
  13  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
  14  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
  15  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
  16  *  Wendling.
  17  * The list_for_each() macro wasn't appropriate for the sysctl loop.
  18  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
  19  */
  20
  21 #include <linux/config.h>
  22 #include <linux/module.h>
  23 #include <linux/mm.h>
  24 #include <linux/swap.h>
  25 #include <linux/slab.h>
  26 #include <linux/sysctl.h>
  27 #include <linux/proc_fs.h>
  28 #include <linux/ctype.h>
  29 #include <linux/utsname.h>
  30 #include <linux/capability.h>
  31 #include <linux/smp_lock.h>
  32 #include <linux/init.h>
  33 #include <linux/kernel.h>
  34 #include <linux/sysrq.h>
  35 #include <linux/highuid.h>
  36 #include <linux/writeback.h>
  37 #include <linux/hugetlb.h>
  38 #include <linux/security.h>
  39 #include <linux/initrd.h>
  40 #include <linux/times.h>
  41 #include <linux/limits.h>
  42 #include <linux/dcache.h>
  43 #include <linux/syscalls.h>
  44
  45 #include <asm/uaccess.h>
  46 #include <asm/processor.h>
  47
  48 #ifdef CONFIG_ROOT_NFS
  49 #include <linux/nfs_fs.h>
  50 #endif
  51
  52 #if defined(CONFIG_SYSCTL)
  53
  54 /* External variables not in a header file. */
  55 extern int C_A_D;
  56 extern int sysctl_overcommit_memory;
  57 extern int sysctl_overcommit_ratio;
  58 extern int max_threads;
  59 extern int sysrq_enabled;
  60 extern int core_uses_pid;
  61 extern char core_pattern[];
  62 extern int cad_pid;
  63 extern int pid_max;
  64 extern int min_free_kbytes;
  65 extern int printk_ratelimit_jiffies;
  66 extern int printk_ratelimit_burst;
  67 extern int pid_max_min, pid_max_max;
  68
  69 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
  70 int unknown_nmi_panic;
  71 extern int proc_unknown_nmi_panic(ctl_table *, int, struct file *,
  72                                   void __user *, size_t *, loff_t *);
  73 #endif
  74
  75 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
  76 static int maxolduid = 65535;
  77 static int minolduid;
  78
  79 static int ngroups_max = NGROUPS_MAX;
  80
  81 #ifdef CONFIG_KMOD
  82 extern char modprobe_path[];
  83 #endif
  84 #ifdef CONFIG_HOTPLUG
  85 extern char hotplug_path[];
  86 #endif
  87 extern char vshelper_path[];
  88 #ifdef CONFIG_CHR_DEV_SG
  89 extern int sg_big_buff;
  90 #endif
  91 #ifdef CONFIG_SYSVIPC
  92 extern size_t shm_ctlmax;
  93 extern size_t shm_ctlall;
  94 extern int shm_ctlmni;
  95 extern int msg_ctlmax;
  96 extern int msg_ctlmnb;
  97 extern int msg_ctlmni;
  98 extern int sem_ctls[];
  99 #endif
 100
 101 #ifdef __sparc__
 102 extern char reboot_command [];
 103 extern int stop_a_enabled;
 104 extern int scons_pwroff;
 105 #endif
 106
 107 #ifdef __hppa__
 108 extern int pwrsw_enabled;
 109 extern int unaligned_enabled;
 110 #endif
 111
 112 #ifdef CONFIG_ARCH_S390
 113 #ifdef CONFIG_MATHEMU
 114 extern int sysctl_ieee_emulation_warnings;
 115 #endif
 116 extern int sysctl_userprocess_debug;
 117 #endif
 118
 119 extern int sysctl_hz_timer;
 120
 121 #ifdef CONFIG_BSD_PROCESS_ACCT
 122 extern int acct_parm[];
 123 #endif
 124
 125 static int parse_table(int __user *, int, void __user *, size_t __user *, void __user *, size_t,
 126                        ctl_table *, void **);
 127 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
 128                   void __user *buffer, size_t *lenp, loff_t *ppos);
 129
 130 static ctl_table root_table[];
 131 static struct ctl_table_header root_table_header =
 132         { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
 133
 134 static ctl_table kern_table[];
 135 static ctl_table vm_table[];
 136 #ifdef CONFIG_NET
 137 extern ctl_table net_table[];
 138 #endif
 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
 148 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 149 int sysctl_legacy_va_layout;
 150 #endif
 151
 152 /* /proc declarations: */
 153
 154 #ifdef CONFIG_PROC_FS
 155
 156 static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
 157 static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
 158 static int proc_opensys(struct inode *, struct file *);
 159
 160 struct file_operations proc_sys_file_operations = {
 161         .open           = proc_opensys,
 162         .read           = proc_readsys,
 163         .write          = proc_writesys,
 164 };
 165
 166 extern struct proc_dir_entry *proc_sys_root;
 167
 168 static void register_proc_table(ctl_table *, struct proc_dir_entry *);
 169 static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
 170 #endif
 171
 172 /* The default sysctl tables: */
 173
 174 static ctl_table root_table[] = {
 175         {
 176                 .ctl_name       = CTL_KERN,
 177                 .procname       = "kernel",
 178                 .mode           = 0555,
 179                 .child          = kern_table,
 180         },
 181         {
 182                 .ctl_name       = CTL_VM,
 183                 .procname       = "vm",
 184                 .mode           = 0555,
 185                 .child          = vm_table,
 186         },
 187 #ifdef CONFIG_NET
 188         {
 189                 .ctl_name       = CTL_NET,
 190                 .procname       = "net",
 191                 .mode           = 0555,
 192                 .child          = net_table,
 193         },
 194 #endif
 195         {
 196                 .ctl_name       = CTL_PROC,
 197                 .procname       = "proc",
 198                 .mode           = 0555,
 199                 .child          = proc_table,
 200         },
 201         {
 202                 .ctl_name       = CTL_FS,
 203                 .procname       = "fs",
 204                 .mode           = 0555,
 205                 .child          = fs_table,
 206         },
 207         {
 208                 .ctl_name       = CTL_DEBUG,
 209                 .procname       = "debug",
 210                 .mode           = 0555,
 211                 .child          = debug_table,
 212         },
 213         {
 214                 .ctl_name       = CTL_DEV,
 215                 .procname       = "dev",
 216                 .mode           = 0555,
 217                 .child          = dev_table,
 218         },
 219         { .ctl_name = 0 }
 220 };
 221
 222 static ctl_table kern_table[] = {
 223         {
 224                 .ctl_name       = KERN_OSTYPE,
 225                 .procname       = "ostype",
 226                 .data           = system_utsname.sysname,
 227                 .maxlen         = sizeof(system_utsname.sysname),
 228                 .mode           = 0444,
 229                 .proc_handler   = &proc_doutsstring,
 230                 .strategy       = &sysctl_string,
 231         },
 232         {
 233                 .ctl_name       = KERN_OSRELEASE,
 234                 .procname       = "osrelease",
 235                 .data           = system_utsname.release,
 236                 .maxlen         = sizeof(system_utsname.release),
 237                 .mode           = 0444,
 238                 .proc_handler   = &proc_doutsstring,
 239                 .strategy       = &sysctl_string,
 240         },
 241         {
 242                 .ctl_name       = KERN_VERSION,
 243                 .procname       = "version",
 244                 .data           = system_utsname.version,
 245                 .maxlen         = sizeof(system_utsname.version),
 246                 .mode           = 0444,
 247                 .proc_handler   = &proc_doutsstring,
 248                 .strategy       = &sysctl_string,
 249         },
 250         {
 251                 .ctl_name       = KERN_NODENAME,
 252                 .procname       = "hostname",
 253                 .data           = system_utsname.nodename,
 254                 .maxlen         = sizeof(system_utsname.nodename),
 255                 .mode           = 0644,
 256                 .proc_handler   = &proc_doutsstring,
 257                 .strategy       = &sysctl_string,
 258         },
 259         {
 260                 .ctl_name       = KERN_DOMAINNAME,
 261                 .procname       = "domainname",
 262                 .data           = system_utsname.domainname,
 263                 .maxlen         = sizeof(system_utsname.domainname),
 264                 .mode           = 0644,
 265                 .proc_handler   = &proc_doutsstring,
 266                 .strategy       = &sysctl_string,
 267         },
 268         {
 269                 .ctl_name       = KERN_PANIC,
 270                 .procname       = "panic",
 271                 .data           = &panic_timeout,
 272                 .maxlen         = sizeof(int),
 273                 .mode           = 0644,
 274                 .proc_handler   = &proc_dointvec,
 275         },
 276         {
 277                 .ctl_name       = KERN_CORE_USES_PID,
 278                 .procname       = "core_uses_pid",
 279                 .data           = &core_uses_pid,
 280                 .maxlen         = sizeof(int),
 281                 .mode           = 0644,
 282                 .proc_handler   = &proc_dointvec,
 283         },
 284         {
 285                 .ctl_name       = KERN_CORE_PATTERN,
 286                 .procname       = "core_pattern",
 287                 .data           = core_pattern,
 288                 .maxlen         = 64,
 289                 .mode           = 0644,
 290                 .proc_handler   = &proc_dostring,
 291                 .strategy       = &sysctl_string,
 292         },
 293         {
 294                 .ctl_name       = KERN_TAINTED,
 295                 .procname       = "tainted",
 296                 .data           = &tainted,
 297                 .maxlen         = sizeof(int),
 298                 .mode           = 0444,
 299                 .proc_handler   = &proc_dointvec,
 300         },
 301         {
 302                 .ctl_name       = KERN_CAP_BSET,
 303                 .procname       = "cap-bound",
 304                 .data           = &cap_bset,
 305                 .maxlen         = sizeof(kernel_cap_t),
 306                 .mode           = 0600,
 307                 .proc_handler   = &proc_dointvec_bset,
 308         },
 309 #ifdef CONFIG_BLK_DEV_INITRD
 310         {
 311                 .ctl_name       = KERN_REALROOTDEV,
 312                 .procname       = "real-root-dev",
 313                 .data           = &real_root_dev,
 314                 .maxlen         = sizeof(int),
 315                 .mode           = 0644,
 316                 .proc_handler   = &proc_dointvec,
 317         },
 318 #endif
 319 #ifdef __sparc__
 320         {
 321                 .ctl_name       = KERN_SPARC_REBOOT,
 322                 .procname       = "reboot-cmd",
 323                 .data           = reboot_command,
 324                 .maxlen         = 256,
 325                 .mode           = 0644,
 326                 .proc_handler   = &proc_dostring,
 327                 .strategy       = &sysctl_string,
 328         },
 329         {
 330                 .ctl_name       = KERN_SPARC_STOP_A,
 331                 .procname       = "stop-a",
 332                 .data           = &stop_a_enabled,
 333                 .maxlen         = sizeof (int),
 334                 .mode           = 0644,
 335                 .proc_handler   = &proc_dointvec,
 336         },
 337         {
 338                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 339                 .procname       = "scons-poweroff",
 340                 .data           = &scons_pwroff,
 341                 .maxlen         = sizeof (int),
 342                 .mode           = 0644,
 343                 .proc_handler   = &proc_dointvec,
 344         },
 345 #endif
 346 #ifdef __hppa__
 347         {
 348                 .ctl_name       = KERN_HPPA_PWRSW,
 349                 .procname       = "soft-power",
 350                 .data           = &pwrsw_enabled,
 351                 .maxlen         = sizeof (int),
 352                 .mode           = 0644,
 353                 .proc_handler   = &proc_dointvec,
 354         },
 355         {
 356                 .ctl_name       = KERN_HPPA_UNALIGNED,
 357                 .procname       = "unaligned-trap",
 358                 .data           = &unaligned_enabled,
 359                 .maxlen         = sizeof (int),
 360                 .mode           = 0644,
 361                 .proc_handler   = &proc_dointvec,
 362         },
 363 #endif
 364         {
 365                 .ctl_name       = KERN_CTLALTDEL,
 366                 .procname       = "ctrl-alt-del",
 367                 .data           = &C_A_D,
 368                 .maxlen         = sizeof(int),
 369                 .mode           = 0644,
 370                 .proc_handler   = &proc_dointvec,
 371         },
 372         {
 373                 .ctl_name       = KERN_PRINTK,
 374                 .procname       = "printk",
 375                 .data           = &console_loglevel,
 376                 .maxlen         = 4*sizeof(int),
 377                 .mode           = 0644,
 378                 .proc_handler   = &proc_dointvec,
 379         },
 380 #ifdef CONFIG_KMOD
 381         {
 382                 .ctl_name       = KERN_MODPROBE,
 383                 .procname       = "modprobe",
 384                 .data           = &modprobe_path,
 385                 .maxlen         = KMOD_PATH_LEN,
 386                 .mode           = 0644,
 387                 .proc_handler   = &proc_dostring,
 388                 .strategy       = &sysctl_string,
 389         },
 390 #endif
 391 #ifdef CONFIG_HOTPLUG
 392         {
 393                 .ctl_name       = KERN_HOTPLUG,
 394                 .procname       = "hotplug",
 395                 .data           = &hotplug_path,
 396                 .maxlen         = HOTPLUG_PATH_LEN,
 397                 .mode           = 0644,
 398                 .proc_handler   = &proc_dostring,
 399                 .strategy       = &sysctl_string,
 400         },
 401 #endif
 402         {
 403                 .ctl_name       = KERN_VSHELPER,
 404                 .procname       = "vshelper",
 405                 .data           = &vshelper_path,
 406                 .maxlen         = 256,
 407                 .mode           = 0644,
 408                 .proc_handler   = &proc_dostring,
 409                 .strategy       = &sysctl_string,
 410         },
 411 #ifdef CONFIG_CHR_DEV_SG
 412         {
 413                 .ctl_name       = KERN_SG_BIG_BUFF,
 414                 .procname       = "sg-big-buff",
 415                 .data           = &sg_big_buff,
 416                 .maxlen         = sizeof (int),
 417                 .mode           = 0444,
 418                 .proc_handler   = &proc_dointvec,
 419         },
 420 #endif
 421 #ifdef CONFIG_BSD_PROCESS_ACCT
 422         {
 423                 .ctl_name       = KERN_ACCT,
 424                 .procname       = "acct",
 425                 .data           = &acct_parm,
 426                 .maxlen         = 3*sizeof(int),
 427                 .mode           = 0644,
 428                 .proc_handler   = &proc_dointvec,
 429         },
 430 #endif
 431 #ifdef CONFIG_SYSVIPC
 432         {
 433                 .ctl_name       = KERN_SHMMAX,
 434                 .procname       = "shmmax",
 435                 .data           = &shm_ctlmax,
 436                 .maxlen         = sizeof (size_t),
 437                 .mode           = 0644,
 438                 .proc_handler   = &proc_doulongvec_minmax,
 439         },
 440         {
 441                 .ctl_name       = KERN_SHMALL,
 442                 .procname       = "shmall",
 443                 .data           = &shm_ctlall,
 444                 .maxlen         = sizeof (size_t),
 445                 .mode           = 0644,
 446                 .proc_handler   = &proc_doulongvec_minmax,
 447         },
 448         {
 449                 .ctl_name       = KERN_SHMMNI,
 450                 .procname       = "shmmni",
 451                 .data           = &shm_ctlmni,
 452                 .maxlen         = sizeof (int),
 453                 .mode           = 0644,
 454                 .proc_handler   = &proc_dointvec,
 455         },
 456         {
 457                 .ctl_name       = KERN_MSGMAX,
 458                 .procname       = "msgmax",
 459                 .data           = &msg_ctlmax,
 460                 .maxlen         = sizeof (int),
 461                 .mode           = 0644,
 462                 .proc_handler   = &proc_dointvec,
 463         },
 464         {
 465                 .ctl_name       = KERN_MSGMNI,
 466                 .procname       = "msgmni",
 467                 .data           = &msg_ctlmni,
 468                 .maxlen         = sizeof (int),
 469                 .mode           = 0644,
 470                 .proc_handler   = &proc_dointvec,
 471         },
 472         {
 473                 .ctl_name       = KERN_MSGMNB,
 474                 .procname       =  "msgmnb",
 475                 .data           = &msg_ctlmnb,
 476                 .maxlen         = sizeof (int),
 477                 .mode           = 0644,
 478                 .proc_handler   = &proc_dointvec,
 479         },
 480         {
 481                 .ctl_name       = KERN_SEM,
 482                 .procname       = "sem",
 483                 .data           = &sem_ctls,
 484                 .maxlen         = 4*sizeof (int),
 485                 .mode           = 0644,
 486                 .proc_handler   = &proc_dointvec,
 487         },
 488 #endif
 489 #ifdef CONFIG_MAGIC_SYSRQ
 490         {
 491                 .ctl_name       = KERN_SYSRQ,
 492                 .procname       = "sysrq",
 493                 .data           = &sysrq_enabled,
 494                 .maxlen         = sizeof (int),
 495                 .mode           = 0644,
 496                 .proc_handler   = &proc_dointvec,
 497         },
 498 #endif
 499         {
 500                 .ctl_name       = KERN_CADPID,
 501                 .procname       = "cad_pid",
 502                 .data           = &cad_pid,
 503                 .maxlen         = sizeof (int),
 504                 .mode           = 0600,
 505                 .proc_handler   = &proc_dointvec,
 506         },
 507         {
 508                 .ctl_name       = KERN_MAX_THREADS,
 509                 .procname       = "threads-max",
 510                 .data           = &max_threads,
 511                 .maxlen         = sizeof(int),
 512                 .mode           = 0644,
 513                 .proc_handler   = &proc_dointvec,
 514         },
 515         {
 516                 .ctl_name       = KERN_RANDOM,
 517                 .procname       = "random",
 518                 .mode           = 0555,
 519                 .child          = random_table,
 520         },
 521 #ifdef CONFIG_UNIX98_PTYS
 522         {
 523                 .ctl_name       = KERN_PTY,
 524                 .procname       = "pty",
 525                 .mode           = 0555,
 526                 .child          = pty_table,
 527         },
 528 #endif
 529         {
 530                 .ctl_name       = KERN_OVERFLOWUID,
 531                 .procname       = "overflowuid",
 532                 .data           = &overflowuid,
 533                 .maxlen         = sizeof(int),
 534                 .mode           = 0644,
 535                 .proc_handler   = &proc_dointvec_minmax,
 536                 .strategy       = &sysctl_intvec,
 537                 .extra1         = &minolduid,
 538                 .extra2         = &maxolduid,
 539         },
 540         {
 541                 .ctl_name       = KERN_OVERFLOWGID,
 542                 .procname       = "overflowgid",
 543                 .data           = &overflowgid,
 544                 .maxlen         = sizeof(int),
 545                 .mode           = 0644,
 546                 .proc_handler   = &proc_dointvec_minmax,
 547                 .strategy       = &sysctl_intvec,
 548                 .extra1         = &minolduid,
 549                 .extra2         = &maxolduid,
 550         },
 551 #ifdef CONFIG_ARCH_S390
 552 #ifdef CONFIG_MATHEMU
 553         {
 554                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 555                 .procname       = "ieee_emulation_warnings",
 556                 .data           = &sysctl_ieee_emulation_warnings,
 557                 .maxlen         = sizeof(int),
 558                 .mode           = 0644,
 559                 .proc_handler   = &proc_dointvec,
 560         },
 561 #endif
 562 #ifdef CONFIG_NO_IDLE_HZ
 563         {
 564                 .ctl_name       = KERN_HZ_TIMER,
 565                 .procname       = "hz_timer",
 566                 .data           = &sysctl_hz_timer,
 567                 .maxlen         = sizeof(int),
 568                 .mode           = 0644,
 569                 .proc_handler   = &proc_dointvec,
 570         },
 571 #endif
 572         {
 573                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 574                 .procname       = "userprocess_debug",
 575                 .data           = &sysctl_userprocess_debug,
 576                 .maxlen         = sizeof(int),
 577                 .mode           = 0644,
 578                 .proc_handler   = &proc_dointvec,
 579         },
 580 #endif
 581         {
 582                 .ctl_name       = KERN_PIDMAX,
 583                 .procname       = "pid_max",
 584                 .data           = &pid_max,
 585                 .maxlen         = sizeof (int),
 586                 .mode           = 0644,
 587                 .proc_handler   = &proc_dointvec_minmax,
 588                 .strategy       = sysctl_intvec,
 589                 .extra1         = &pid_max_min,
 590                 .extra2         = &pid_max_max,
 591         },
 592         {
 593                 .ctl_name       = KERN_PANIC_ON_OOPS,
 594                 .procname       = "panic_on_oops",
 595                 .data           = &panic_on_oops,
 596                 .maxlen         = sizeof(int),
 597                 .mode           = 0644,
 598                 .proc_handler   = &proc_dointvec,
 599         },
 600         {
 601                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 602                 .procname       = "printk_ratelimit",
 603                 .data           = &printk_ratelimit_jiffies,
 604                 .maxlen         = sizeof(int),
 605                 .mode           = 0644,
 606                 .proc_handler   = &proc_dointvec_jiffies,
 607                 .strategy       = &sysctl_jiffies,
 608         },
 609         {
 610                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 611                 .procname       = "printk_ratelimit_burst",
 612                 .data           = &printk_ratelimit_burst,
 613                 .maxlen         = sizeof(int),
 614                 .mode           = 0644,
 615                 .proc_handler   = &proc_dointvec,
 616         },
 617         {
 618                 .ctl_name       = KERN_NGROUPS_MAX,
 619                 .procname       = "ngroups_max",
 620                 .data           = &ngroups_max,
 621                 .maxlen         = sizeof (int),
 622                 .mode           = 0444,
 623                 .proc_handler   = &proc_dointvec,
 624         },
 625 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 626         {
 627                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
 628                 .procname       = "unknown_nmi_panic",
 629                 .data           = &unknown_nmi_panic,
 630                 .maxlen         = sizeof (int),
 631                 .mode           = 0644,
 632                 .proc_handler   = &proc_unknown_nmi_panic,
 633         },
 634 #endif
 635 #if defined(CONFIG_X86)
 636         {
 637                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 638                 .procname       = "bootloader_type",
 639                 .data           = &bootloader_type,
 640                 .maxlen         = sizeof (int),
 641                 .mode           = 0444,
 642                 .proc_handler   = &proc_dointvec,
 643         },
 644 #endif
 645         { .ctl_name = 0 }
 646 };
 647
 648 /* Constants for minimum and maximum testing in vm_table.
 649    We use these as one-element integer vectors. */
 650 static int zero;
 651 static int one_hundred = 100;
 652
 653
 654 static ctl_table vm_table[] = {
 655         {
 656                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
 657                 .procname       = "overcommit_memory",
 658                 .data           = &sysctl_overcommit_memory,
 659                 .maxlen         = sizeof(sysctl_overcommit_memory),
 660                 .mode           = 0644,
 661                 .proc_handler   = &proc_dointvec,
 662         },
 663         {
 664                 .ctl_name       = VM_OVERCOMMIT_RATIO,
 665                 .procname       = "overcommit_ratio",
 666                 .data           = &sysctl_overcommit_ratio,
 667                 .maxlen         = sizeof(sysctl_overcommit_ratio),
 668                 .mode           = 0644,
 669                 .proc_handler   = &proc_dointvec,
 670         },
 671         {
 672                 .ctl_name       = VM_PAGE_CLUSTER,
 673                 .procname       = "page-cluster",
 674                 .data           = &page_cluster,
 675                 .maxlen         = sizeof(int),
 676                 .mode           = 0644,
 677                 .proc_handler   = &proc_dointvec,
 678         },
 679         {
 680                 .ctl_name       = VM_DIRTY_BACKGROUND,
 681                 .procname       = "dirty_background_ratio",
 682                 .data           = &dirty_background_ratio,
 683                 .maxlen         = sizeof(dirty_background_ratio),
 684                 .mode           = 0644,
 685                 .proc_handler   = &proc_dointvec_minmax,
 686                 .strategy       = &sysctl_intvec,
 687                 .extra1         = &zero,
 688                 .extra2         = &one_hundred,
 689         },
 690         {
 691                 .ctl_name       = VM_DIRTY_RATIO,
 692                 .procname       = "dirty_ratio",
 693                 .data           = &vm_dirty_ratio,
 694                 .maxlen         = sizeof(vm_dirty_ratio),
 695                 .mode           = 0644,
 696                 .proc_handler   = &proc_dointvec_minmax,
 697                 .strategy       = &sysctl_intvec,
 698                 .extra1         = &zero,
 699                 .extra2         = &one_hundred,
 700         },
 701         {
 702                 .ctl_name       = VM_DIRTY_WB_CS,
 703                 .procname       = "dirty_writeback_centisecs",
 704                 .data           = &dirty_writeback_centisecs,
 705                 .maxlen         = sizeof(dirty_writeback_centisecs),
 706                 .mode           = 0644,
 707                 .proc_handler   = &dirty_writeback_centisecs_handler,
 708         },
 709         {
 710                 .ctl_name       = VM_DIRTY_EXPIRE_CS,
 711                 .procname       = "dirty_expire_centisecs",
 712                 .data           = &dirty_expire_centisecs,
 713                 .maxlen         = sizeof(dirty_expire_centisecs),
 714                 .mode           = 0644,
 715                 .proc_handler   = &proc_dointvec,
 716         },
 717         {
 718                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
 719                 .procname       = "nr_pdflush_threads",
 720                 .data           = &nr_pdflush_threads,
 721                 .maxlen         = sizeof nr_pdflush_threads,
 722                 .mode           = 0444 /* read-only*/,
 723                 .proc_handler   = &proc_dointvec,
 724         },
 725         {
 726                 .ctl_name       = VM_SWAPPINESS,
 727                 .procname       = "swappiness",
 728                 .data           = &vm_swappiness,
 729                 .maxlen         = sizeof(vm_swappiness),
 730                 .mode           = 0644,
 731                 .proc_handler   = &proc_dointvec_minmax,
 732                 .strategy       = &sysctl_intvec,
 733                 .extra1         = &zero,
 734                 .extra2         = &one_hundred,
 735         },
 736 #ifdef CONFIG_HUGETLB_PAGE
 737          {
 738                 .ctl_name       = VM_HUGETLB_PAGES,
 739                 .procname       = "nr_hugepages",
 740                 .data           = &max_huge_pages,
 741                 .maxlen         = sizeof(unsigned long),
 742                 .mode           = 0644,
 743                 .proc_handler   = &hugetlb_sysctl_handler,
 744                 .extra1         = (void *)&hugetlb_zero,
 745                 .extra2         = (void *)&hugetlb_infinity,
 746          },
 747          {
 748                 .ctl_name       = VM_HUGETLB_GROUP,
 749                 .procname       = "hugetlb_shm_group",
 750                 .data           = &sysctl_hugetlb_shm_group,
 751                 .maxlen         = sizeof(gid_t),
 752                 .mode           = 0644,
 753                 .proc_handler   = &proc_dointvec,
 754          },
 755 #endif
 756         {
 757                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
 758                 .procname       = "lowmem_reserve_ratio",
 759                 .data           = &sysctl_lowmem_reserve_ratio,
 760                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
 761                 .mode           = 0644,
 762                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
 763                 .strategy       = &sysctl_intvec,
 764         },
 765         {
 766                 .ctl_name       = VM_MIN_FREE_KBYTES,
 767                 .procname       = "min_free_kbytes",
 768                 .data           = &min_free_kbytes,
 769                 .maxlen         = sizeof(min_free_kbytes),
 770                 .mode           = 0644,
 771                 .proc_handler   = &min_free_kbytes_sysctl_handler,
 772                 .strategy       = &sysctl_intvec,
 773                 .extra1         = &zero,
 774         },
 775 #ifdef CONFIG_MMU
 776         {
 777                 .ctl_name       = VM_MAX_MAP_COUNT,
 778                 .procname       = "max_map_count",
 779                 .data           = &sysctl_max_map_count,
 780                 .maxlen         = sizeof(sysctl_max_map_count),
 781                 .mode           = 0644,
 782                 .proc_handler   = &proc_dointvec
 783         },
 784 #endif
 785         {
 786                 .ctl_name       = VM_LAPTOP_MODE,
 787                 .procname       = "laptop_mode",
 788                 .data           = &laptop_mode,
 789                 .maxlen         = sizeof(laptop_mode),
 790                 .mode           = 0644,
 791                 .proc_handler   = &proc_dointvec,
 792                 .strategy       = &sysctl_intvec,
 793                 .extra1         = &zero,
 794         },
 795         {
 796                 .ctl_name       = VM_BLOCK_DUMP,
 797                 .procname       = "block_dump",
 798                 .data           = &block_dump,
 799                 .maxlen         = sizeof(block_dump),
 800                 .mode           = 0644,
 801                 .proc_handler   = &proc_dointvec,
 802                 .strategy       = &sysctl_intvec,
 803                 .extra1         = &zero,
 804         },
 805         {
 806                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
 807                 .procname       = "vfs_cache_pressure",
 808                 .data           = &sysctl_vfs_cache_pressure,
 809                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
 810                 .mode           = 0644,
 811                 .proc_handler   = &proc_dointvec,
 812                 .strategy       = &sysctl_intvec,
 813                 .extra1         = &zero,
 814         },
 815 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 816         {
 817                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
 818                 .procname       = "legacy_va_layout",
 819                 .data           = &sysctl_legacy_va_layout,
 820                 .maxlen         = sizeof(sysctl_legacy_va_layout),
 821                 .mode           = 0644,
 822                 .proc_handler   = &proc_dointvec,
 823                 .strategy       = &sysctl_intvec,
 824                 .extra1         = &zero,
 825         },
 826 #endif
 827 #ifdef CONFIG_SWAP
 828         {
 829                 .ctl_name       = VM_SWAP_TOKEN_TIMEOUT,
 830                 .procname       = "swap_token_timeout",
 831                 .data           = &swap_token_default_timeout,
 832                 .maxlen         = sizeof(swap_token_default_timeout),
 833                 .mode           = 0644,
 834                 .proc_handler   = &proc_dointvec_jiffies,
 835                 .strategy       = &sysctl_jiffies,
 836         },
 837 #endif
 838         { .ctl_name = 0 }
 839 };
 840
 841 static ctl_table proc_table[] = {
 842         { .ctl_name = 0 }
 843 };
 844
 845 static ctl_table fs_table[] = {
 846         {
 847                 .ctl_name       = FS_NRINODE,
 848                 .procname       = "inode-nr",
 849                 .data           = &inodes_stat,
 850                 .maxlen         = 2*sizeof(int),
 851                 .mode           = 0444,
 852                 .proc_handler   = &proc_dointvec,
 853         },
 854         {
 855                 .ctl_name       = FS_STATINODE,
 856                 .procname       = "inode-state",
 857                 .data           = &inodes_stat,
 858                 .maxlen         = 7*sizeof(int),
 859                 .mode           = 0444,
 860                 .proc_handler   = &proc_dointvec,
 861         },
 862         {
 863                 .ctl_name       = FS_NRFILE,
 864                 .procname       = "file-nr",
 865                 .data           = &files_stat,
 866                 .maxlen         = 3*sizeof(int),
 867                 .mode           = 0444,
 868                 .proc_handler   = &proc_dointvec,
 869         },
 870         {
 871                 .ctl_name       = FS_MAXFILE,
 872                 .procname       = "file-max",
 873                 .data           = &files_stat.max_files,
 874                 .maxlen         = sizeof(int),
 875                 .mode           = 0644,
 876                 .proc_handler   = &proc_dointvec,
 877         },
 878         {
 879                 .ctl_name       = FS_DENTRY,
 880                 .procname       = "dentry-state",
 881                 .data           = &dentry_stat,
 882                 .maxlen         = 6*sizeof(int),
 883                 .mode           = 0444,
 884                 .proc_handler   = &proc_dointvec,
 885         },
 886         {
 887                 .ctl_name       = FS_OVERFLOWUID,
 888                 .procname       = "overflowuid",
 889                 .data           = &fs_overflowuid,
 890                 .maxlen         = sizeof(int),
 891                 .mode           = 0644,
 892                 .proc_handler   = &proc_dointvec_minmax,
 893                 .strategy       = &sysctl_intvec,
 894                 .extra1         = &minolduid,
 895                 .extra2         = &maxolduid,
 896         },
 897         {
 898                 .ctl_name       = FS_OVERFLOWGID,
 899                 .procname       = "overflowgid",
 900                 .data           = &fs_overflowgid,
 901                 .maxlen         = sizeof(int),
 902                 .mode           = 0644,
 903                 .proc_handler   = &proc_dointvec_minmax,
 904                 .strategy       = &sysctl_intvec,
 905                 .extra1         = &minolduid,
 906                 .extra2         = &maxolduid,
 907         },
 908         {
 909                 .ctl_name       = FS_LEASES,
 910                 .procname       = "leases-enable",
 911                 .data           = &leases_enable,
 912                 .maxlen         = sizeof(int),
 913                 .mode           = 0644,
 914                 .proc_handler   = &proc_dointvec,
 915         },
 916 #ifdef CONFIG_DNOTIFY
 917         {
 918                 .ctl_name       = FS_DIR_NOTIFY,
 919                 .procname       = "dir-notify-enable",
 920                 .data           = &dir_notify_enable,
 921                 .maxlen         = sizeof(int),
 922                 .mode           = 0644,
 923                 .proc_handler   = &proc_dointvec,
 924         },
 925 #endif
 926 #ifdef CONFIG_MMU
 927         {
 928                 .ctl_name       = FS_LEASE_TIME,
 929                 .procname       = "lease-break-time",
 930                 .data           = &lease_break_time,
 931                 .maxlen         = sizeof(int),
 932                 .mode           = 0644,
 933                 .proc_handler   = &proc_dointvec,
 934         },
 935         {
 936                 .ctl_name       = FS_AIO_NR,
 937                 .procname       = "aio-nr",
 938                 .data           = &aio_nr,
 939                 .maxlen         = sizeof(aio_nr),
 940                 .mode           = 0444,
 941                 .proc_handler   = &proc_dointvec,
 942         },
 943         {
 944                 .ctl_name       = FS_AIO_MAX_NR,
 945                 .procname       = "aio-max-nr",
 946                 .data           = &aio_max_nr,
 947                 .maxlen         = sizeof(aio_max_nr),
 948                 .mode           = 0644,
 949                 .proc_handler   = &proc_dointvec,
 950         },
 951 #endif
 952         { .ctl_name = 0 }
 953 };
 954
 955 static ctl_table debug_table[] = {
 956         { .ctl_name = 0 }
 957 };
 958
 959 static ctl_table dev_table[] = {
 960         { .ctl_name = 0 }
 961 };
 962
 963 extern void init_irq_proc (void);
 964
 965 void __init sysctl_init(void)
 966 {
 967 #ifdef CONFIG_PROC_FS
 968         register_proc_table(root_table, proc_sys_root);
 969         init_irq_proc();
 970 #endif
 971 }
 972
 973 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
 974                void __user *newval, size_t newlen)
 975 {
 976         struct list_head *tmp;
 977
 978         if (nlen <= 0 || nlen >= CTL_MAXNAME)
 979                 return -ENOTDIR;
 980         if (oldval) {
 981                 int old_len;
 982                 if (!oldlenp || get_user(old_len, oldlenp))
 983                         return -EFAULT;
 984         }
 985         tmp = &root_table_header.ctl_entry;
 986         do {
 987                 struct ctl_table_header *head =
 988                         list_entry(tmp, struct ctl_table_header, ctl_entry);
 989                 void *context = NULL;
 990                 int error = parse_table(name, nlen, oldval, oldlenp,
 991                                         newval, newlen, head->ctl_table,
 992                                         &context);
 993                 if (context)
 994                         kfree(context);
 995                 if (error != -ENOTDIR)
 996                         return error;
 997                 tmp = tmp->next;
 998         } while (tmp != &root_table_header.ctl_entry);
 999         return -ENOTDIR;
1000 }
1001
1002 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1003 {
1004         struct __sysctl_args tmp;
1005         int error;
1006
1007         if (copy_from_user(&tmp, args, sizeof(tmp)))
1008                 return -EFAULT;
1009
1010         lock_kernel();
1011         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1012                           tmp.newval, tmp.newlen);
1013         unlock_kernel();
1014         return error;
1015 }
1016
1017 /*
1018  * ctl_perm does NOT grant the superuser all rights automatically, because
1019  * some sysctl variables are readonly even to root.
1020  */
1021
1022 static int test_perm(int mode, int op)
1023 {
1024         if (!current->euid)
1025                 mode >>= 6;
1026         else if (in_egroup_p(0))
1027                 mode >>= 3;
1028         if ((mode & op & 0007) == op)
1029                 return 0;
1030         return -EACCES;
1031 }
1032
1033 static inline int ctl_perm(ctl_table *table, int op)
1034 {
1035         int error;
1036         error = security_sysctl(table, op);
1037         if (error)
1038                 return error;
1039         return test_perm(table->mode, op);
1040 }
1041
1042 static int parse_table(int __user *name, int nlen,
1043                        void __user *oldval, size_t __user *oldlenp,
1044                        void __user *newval, size_t newlen,
1045                        ctl_table *table, void **context)
1046 {
1047         int n;
1048 repeat:
1049         if (!nlen)
1050                 return -ENOTDIR;
1051         if (get_user(n, name))
1052                 return -EFAULT;
1053         for ( ; table->ctl_name; table++) {
1054                 if (n == table->ctl_name || table->ctl_name == CTL_ANY) {
1055                         int error;
1056                         if (table->child) {
1057                                 if (ctl_perm(table, 001))
1058                                         return -EPERM;
1059                                 if (table->strategy) {
1060                                         error = table->strategy(
1061                                                 table, name, nlen,
1062                                                 oldval, oldlenp,
1063                                                 newval, newlen, context);
1064                                         if (error)
1065                                                 return error;
1066                                 }
1067                                 name++;
1068                                 nlen--;
1069                                 table = table->child;
1070                                 goto repeat;
1071                         }
1072                         error = do_sysctl_strategy(table, name, nlen,
1073                                                    oldval, oldlenp,
1074                                                    newval, newlen, context);
1075                         return error;
1076                 }
1077         }
1078         return -ENOTDIR;
1079 }
1080
1081 /* Perform the actual read/write of a sysctl table entry. */
1082 int do_sysctl_strategy (ctl_table *table,
1083                         int __user *name, int nlen,
1084                         void __user *oldval, size_t __user *oldlenp,
1085                         void __user *newval, size_t newlen, void **context)
1086 {
1087         int op = 0, rc;
1088         size_t len;
1089
1090         if (oldval)
1091                 op |= 004;
1092         if (newval)
1093                 op |= 002;
1094         if (ctl_perm(table, op))
1095                 return -EPERM;
1096
1097         if (table->strategy) {
1098                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1099                                      newval, newlen, context);
1100                 if (rc < 0)
1101                         return rc;
1102                 if (rc > 0)
1103                         return 0;
1104         }
1105
1106         /* If there is no strategy routine, or if the strategy returns
1107          * zero, proceed with automatic r/w */
1108         if (table->data && table->maxlen) {
1109                 if (oldval && oldlenp) {
1110                         if (get_user(len, oldlenp))
1111                                 return -EFAULT;
1112                         if (len) {
1113                                 if (len > table->maxlen)
1114                                         len = table->maxlen;
1115                                 if(copy_to_user(oldval, table->data, len))
1116                                         return -EFAULT;
1117                                 if(put_user(len, oldlenp))
1118                                         return -EFAULT;
1119                         }
1120                 }
1121                 if (newval && newlen) {
1122                         len = newlen;
1123                         if (len > table->maxlen)
1124                                 len = table->maxlen;
1125                         if(copy_from_user(table->data, newval, len))
1126                                 return -EFAULT;
1127                 }
1128         }
1129         return 0;
1130 }
1131
1132 /**
1133  * register_sysctl_table - register a sysctl hierarchy
1134  * @table: the top-level table structure
1135  * @insert_at_head: whether the entry should be inserted in front or at the end
1136  *
1137  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1138  * array. An entry with a ctl_name of 0 terminates the table.
1139  *
1140  * The members of the &ctl_table structure are used as follows:
1141  *
1142  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1143  *            must be unique within that level of sysctl
1144  *
1145  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1146  *            enter a sysctl file
1147  *
1148  * data - a pointer to data for use by proc_handler
1149  *
1150  * maxlen - the maximum size in bytes of the data
1151  *
1152  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1153  *
1154  * child - a pointer to the child sysctl table if this entry is a directory, or
1155  *         %NULL.
1156  *
1157  * proc_handler - the text handler routine (described below)
1158  *
1159  * strategy - the strategy routine (described below)
1160  *
1161  * de - for internal use by the sysctl routines
1162  *
1163  * extra1, extra2 - extra pointers usable by the proc handler routines
1164  *
1165  * Leaf nodes in the sysctl tree will be represented by a single file
1166  * under /proc; non-leaf nodes will be represented by directories.
1167  *
1168  * sysctl(2) can automatically manage read and write requests through
1169  * the sysctl table.  The data and maxlen fields of the ctl_table
1170  * struct enable minimal validation of the values being written to be
1171  * performed, and the mode field allows minimal authentication.
1172  *
1173  * More sophisticated management can be enabled by the provision of a
1174  * strategy routine with the table entry.  This will be called before
1175  * any automatic read or write of the data is performed.
1176  *
1177  * The strategy routine may return
1178  *
1179  * < 0 - Error occurred (error is passed to user process)
1180  *
1181  * 0   - OK - proceed with automatic read or write.
1182  *
1183  * > 0 - OK - read or write has been done by the strategy routine, so
1184  *       return immediately.
1185  *
1186  * There must be a proc_handler routine for any terminal nodes
1187  * mirrored under /proc/sys (non-terminals are handled by a built-in
1188  * directory handler).  Several default handlers are available to
1189  * cover common cases -
1190  *
1191  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1192  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1193  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1194  *
1195  * It is the handler's job to read the input buffer from user memory
1196  * and process it. The handler should return 0 on success.
1197  *
1198  * This routine returns %NULL on a failure to register, and a pointer
1199  * to the table header on success.
1200  */
1201 struct ctl_table_header *register_sysctl_table(ctl_table * table,
1202                                                int insert_at_head)
1203 {
1204         struct ctl_table_header *tmp;
1205         tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1206         if (!tmp)
1207                 return NULL;
1208         tmp->ctl_table = table;
1209         INIT_LIST_HEAD(&tmp->ctl_entry);
1210         if (insert_at_head)
1211                 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
1212         else
1213                 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1214 #ifdef CONFIG_PROC_FS
1215         register_proc_table(table, proc_sys_root);
1216 #endif
1217         return tmp;
1218 }
1219
1220 /**
1221  * unregister_sysctl_table - unregister a sysctl table hierarchy
1222  * @header: the header returned from register_sysctl_table
1223  *
1224  * Unregisters the sysctl table and all children. proc entries may not
1225  * actually be removed until they are no longer used by anyone.
1226  */
1227 void unregister_sysctl_table(struct ctl_table_header * header)
1228 {
1229         list_del(&header->ctl_entry);
1230 #ifdef CONFIG_PROC_FS
1231         unregister_proc_table(header->ctl_table, proc_sys_root);
1232 #endif
1233         kfree(header);
1234 }
1235
1236 /*
1237  * /proc/sys support
1238  */
1239
1240 #ifdef CONFIG_PROC_FS
1241
1242 /* Scan the sysctl entries in table and add them all into /proc */
1243 static void register_proc_table(ctl_table * table, struct proc_dir_entry *root)
1244 {
1245         struct proc_dir_entry *de;
1246         int len;
1247         mode_t mode;
1248
1249         for (; table->ctl_name; table++) {
1250                 /* Can't do anything without a proc name. */
1251                 if (!table->procname)
1252                         continue;
1253                 /* Maybe we can't do anything with it... */
1254                 if (!table->proc_handler && !table->child) {
1255                         printk(KERN_WARNING "SYSCTL: Can't register %s\n",
1256                                 table->procname);
1257                         continue;
1258                 }
1259
1260                 len = strlen(table->procname);
1261                 mode = table->mode;
1262
1263                 de = NULL;
1264                 if (table->proc_handler)
1265                         mode |= S_IFREG;
1266                 else {
1267                         mode |= S_IFDIR;
1268                         for (de = root->subdir; de; de = de->next) {
1269                                 if (proc_match(len, table->procname, de))
1270                                         break;
1271                         }
1272                         /* If the subdir exists already, de is non-NULL */
1273                 }
1274
1275                 if (!de) {
1276                         de = create_proc_entry(table->procname, mode, root);
1277                         if (!de)
1278                                 continue;
1279                         de->data = (void *) table;
1280                         if (table->proc_handler)
1281                                 de->proc_fops = &proc_sys_file_operations;
1282                 }
1283                 table->de = de;
1284                 if (de->mode & S_IFDIR)
1285                         register_proc_table(table->child, de);
1286         }
1287 }
1288
1289 /*
1290  * Unregister a /proc sysctl table and any subdirectories.
1291  */
1292 static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
1293 {
1294         struct proc_dir_entry *de;
1295         for (; table->ctl_name; table++) {
1296                 if (!(de = table->de))
1297                         continue;
1298                 if (de->mode & S_IFDIR) {
1299                         if (!table->child) {
1300                                 printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
1301                                 continue;
1302                         }
1303                         unregister_proc_table(table->child, de);
1304
1305                         /* Don't unregister directories which still have entries.. */
1306                         if (de->subdir)
1307                                 continue;
1308                 }
1309
1310                 /* Don't unregister proc entries that are still being used.. */
1311                 if (atomic_read(&de->count))
1312                         continue;
1313
1314                 table->de = NULL;
1315                 remove_proc_entry(table->procname, root);
1316         }
1317 }
1318
1319 static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
1320                           size_t count, loff_t *ppos)
1321 {
1322         int op;
1323         struct proc_dir_entry *de;
1324         struct ctl_table *table;
1325         size_t res;
1326         ssize_t error;
1327
1328         de = PDE(file->f_dentry->d_inode);
1329         if (!de || !de->data)
1330                 return -ENOTDIR;
1331         table = (struct ctl_table *) de->data;
1332         if (!table || !table->proc_handler)
1333                 return -ENOTDIR;
1334         op = (write ? 002 : 004);
1335         if (ctl_perm(table, op))
1336                 return -EPERM;
1337
1338         res = count;
1339
1340         error = (*table->proc_handler) (table, write, file, buf, &res, ppos);
1341         if (error)
1342                 return error;
1343         return res;
1344 }
1345
1346 static int proc_opensys(struct inode *inode, struct file *file)
1347 {
1348         if (file->f_mode & FMODE_WRITE) {
1349                 /*
1350                  * sysctl entries that are not writable,
1351                  * are _NOT_ writable, capabilities or not.
1352                  */
1353                 if (!(inode->i_mode & S_IWUSR))
1354                         return -EPERM;
1355         }
1356
1357         return 0;
1358 }
1359
1360 static ssize_t proc_readsys(struct file * file, char __user * buf,
1361                             size_t count, loff_t *ppos)
1362 {
1363         return do_rw_proc(0, file, buf, count, ppos);
1364 }
1365
1366 static ssize_t proc_writesys(struct file * file, const char __user * buf,
1367                              size_t count, loff_t *ppos)
1368 {
1369         return do_rw_proc(1, file, (char __user *) buf, count, ppos);
1370 }
1371
1372 /**
1373  * proc_dostring - read a string sysctl
1374  * @table: the sysctl table
1375  * @write: %TRUE if this is a write to the sysctl file
1376  * @filp: the file structure
1377  * @buffer: the user buffer
1378  * @lenp: the size of the user buffer
1379  *
1380  * Reads/writes a string from/to the user buffer. If the kernel
1381  * buffer provided is not large enough to hold the string, the
1382  * string is truncated. The copied string is %NULL-terminated.
1383  * If the string is being read by the user process, it is copied
1384  * and a newline '\n' is added. It is truncated if the buffer is
1385  * not large enough.
1386  *
1387  * Returns 0 on success.
1388  */
1389 int proc_dostring(ctl_table *table, int write, struct file *filp,
1390                   void __user *buffer, size_t *lenp, loff_t *ppos)
1391 {
1392         size_t len;
1393         char __user *p;
1394         char c;
1395
1396         if (!table->data || !table->maxlen || !*lenp ||
1397             (*ppos && !write)) {
1398                 *lenp = 0;
1399                 return 0;
1400         }
1401
1402         if (write) {
1403                 len = 0;
1404                 p = buffer;
1405                 while (len < *lenp) {
1406                         if (get_user(c, p++))
1407                                 return -EFAULT;
1408                         if (c == 0 || c == '\n')
1409                                 break;
1410                         len++;
1411                 }
1412                 if (len >= table->maxlen)
1413                         len = table->maxlen-1;
1414                 if(copy_from_user(table->data, buffer, len))
1415                         return -EFAULT;
1416                 ((char *) table->data)[len] = 0;
1417                 *ppos += *lenp;
1418         } else {
1419                 len = strlen(table->data);
1420                 if (len > table->maxlen)
1421                         len = table->maxlen;
1422                 if (len > *lenp)
1423                         len = *lenp;
1424                 if (len)
1425                         if(copy_to_user(buffer, table->data, len))
1426                                 return -EFAULT;
1427                 if (len < *lenp) {
1428                         if(put_user('\n', ((char __user *) buffer) + len))
1429                                 return -EFAULT;
1430                         len++;
1431                 }
1432                 *lenp = len;
1433                 *ppos += len;
1434         }
1435         return 0;
1436 }
1437
1438 /*
1439  *      Special case of dostring for the UTS structure. This has locks
1440  *      to observe. Should this be in kernel/sys.c ????
1441  */
1442
1443 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
1444                   void __user *buffer, size_t *lenp, loff_t *ppos)
1445 {
1446         int r;
1447
1448         if (!write) {
1449                 down_read(&uts_sem);
1450                 r=proc_dostring(table,0,filp,buffer,lenp, ppos);
1451                 up_read(&uts_sem);
1452         } else {
1453                 down_write(&uts_sem);
1454                 r=proc_dostring(table,1,filp,buffer,lenp, ppos);
1455                 up_write(&uts_sem);
1456         }
1457         return r;
1458 }
1459
1460 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1461                                  int *valp,
1462                                  int write, void *data)
1463 {
1464         if (write) {
1465                 *valp = *negp ? -*lvalp : *lvalp;
1466         } else {
1467                 int val = *valp;
1468                 if (val < 0) {
1469                         *negp = -1;
1470                         *lvalp = (unsigned long)-val;
1471                 } else {
1472                         *negp = 0;
1473                         *lvalp = (unsigned long)val;
1474                 }
1475         }
1476         return 0;
1477 }
1478
1479 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1480                   void __user *buffer, size_t *lenp, loff_t *ppos,
1481                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1482                               int write, void *data),
1483                   void *data)
1484 {
1485 #define TMPBUFLEN 21
1486         int *i, vleft, first=1, neg, val;
1487         unsigned long lval;
1488         size_t left, len;
1489
1490         char buf[TMPBUFLEN], *p;
1491         char __user *s = buffer;
1492
1493         if (!table->data || !table->maxlen || !*lenp ||
1494             (*ppos && !write)) {
1495                 *lenp = 0;
1496                 return 0;
1497         }
1498
1499         i = (int *) table->data;
1500         vleft = table->maxlen / sizeof(*i);
1501         left = *lenp;
1502
1503         if (!conv)
1504                 conv = do_proc_dointvec_conv;
1505
1506         for (; left && vleft--; i++, first=0) {
1507                 if (write) {
1508                         while (left) {
1509                                 char c;
1510                                 if (get_user(c, s))
1511                                         return -EFAULT;
1512                                 if (!isspace(c))
1513                                         break;
1514                                 left--;
1515                                 s++;
1516                         }
1517                         if (!left)
1518                                 break;
1519                         neg = 0;
1520                         len = left;
1521                         if (len > sizeof(buf) - 1)
1522                                 len = sizeof(buf) - 1;
1523                         if (copy_from_user(buf, s, len))
1524                                 return -EFAULT;
1525                         buf[len] = 0;
1526                         p = buf;
1527                         if (*p == '-' && left > 1) {
1528                                 neg = 1;
1529                                 left--, p++;
1530                         }
1531                         if (*p < '0' || *p > '9')
1532                                 break;
1533
1534                         lval = simple_strtoul(p, &p, 0);
1535
1536                         len = p-buf;
1537                         if ((len < left) && *p && !isspace(*p))
1538                                 break;
1539                         if (neg)
1540                                 val = -val;
1541                         s += len;
1542                         left -= len;
1543
1544                         if (conv(&neg, &lval, i, 1, data))
1545                                 break;
1546                 } else {
1547                         p = buf;
1548                         if (!first)
1549                                 *p++ = '\t';
1550
1551                         if (conv(&neg, &lval, i, 0, data))
1552                                 break;
1553
1554                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
1555                         len = strlen(buf);
1556                         if (len > left)
1557                                 len = left;
1558                         if(copy_to_user(s, buf, len))
1559                                 return -EFAULT;
1560                         left -= len;
1561                         s += len;
1562                 }
1563         }
1564
1565         if (!write && !first && left) {
1566                 if(put_user('\n', s))
1567                         return -EFAULT;
1568                 left--, s++;
1569         }
1570         if (write) {
1571                 while (left) {
1572                         char c;
1573                         if (get_user(c, s++))
1574                                 return -EFAULT;
1575                         if (!isspace(c))
1576                                 break;
1577                         left--;
1578                 }
1579         }
1580         if (write && first)
1581                 return -EINVAL;
1582         *lenp -= left;
1583         *ppos += *lenp;
1584         return 0;
1585 #undef TMPBUFLEN
1586 }
1587
1588 /**
1589  * proc_dointvec - read a vector of integers
1590  * @table: the sysctl table
1591  * @write: %TRUE if this is a write to the sysctl file
1592  * @filp: the file structure
1593  * @buffer: the user buffer
1594  * @lenp: the size of the user buffer
1595  *
1596  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1597  * values from/to the user buffer, treated as an ASCII string.
1598  *
1599  * Returns 0 on success.
1600  */
1601 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1602                      void __user *buffer, size_t *lenp, loff_t *ppos)
1603 {
1604     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1605                             NULL,NULL);
1606 }
1607
1608 #define OP_SET  0
1609 #define OP_AND  1
1610 #define OP_OR   2
1611 #define OP_MAX  3
1612 #define OP_MIN  4
1613
1614 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1615                                       int *valp,
1616                                       int write, void *data)
1617 {
1618         int op = *(int *)data;
1619         if (write) {
1620                 int val = *negp ? -*lvalp : *lvalp;
1621                 switch(op) {
1622                 case OP_SET:    *valp = val; break;
1623                 case OP_AND:    *valp &= val; break;
1624                 case OP_OR:     *valp |= val; break;
1625                 case OP_MAX:    if(*valp < val)
1626                                         *valp = val;
1627                                 break;
1628                 case OP_MIN:    if(*valp > val)
1629                                 *valp = val;
1630                                 break;
1631                 }
1632         } else {
1633                 int val = *valp;
1634                 if (val < 0) {
1635                         *negp = -1;
1636                         *lvalp = (unsigned long)-val;
1637                 } else {
1638                         *negp = 0;
1639                         *lvalp = (unsigned long)val;
1640                 }
1641         }
1642         return 0;
1643 }
1644
1645 /*
1646  *      init may raise the set.
1647  */
1648
1649 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1650                         void __user *buffer, size_t *lenp, loff_t *ppos)
1651 {
1652         int op;
1653
1654         if (!capable(CAP_SYS_MODULE)) {
1655                 return -EPERM;
1656         }
1657
1658         op = (current->pid == 1) ? OP_SET : OP_AND;
1659         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1660                                 do_proc_dointvec_bset_conv,&op);
1661 }
1662
1663 struct do_proc_dointvec_minmax_conv_param {
1664         int *min;
1665         int *max;
1666 };
1667
1668 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1669                                         int *valp,
1670                                         int write, void *data)
1671 {
1672         struct do_proc_dointvec_minmax_conv_param *param = data;
1673         if (write) {
1674                 int val = *negp ? -*lvalp : *lvalp;
1675                 if ((param->min && *param->min > val) ||
1676                     (param->max && *param->max < val))
1677                         return -EINVAL;
1678                 *valp = val;
1679         } else {
1680                 int val = *valp;
1681                 if (val < 0) {
1682                         *negp = -1;
1683                         *lvalp = (unsigned long)-val;
1684                 } else {
1685                         *negp = 0;
1686                         *lvalp = (unsigned long)val;
1687                 }
1688         }
1689         return 0;
1690 }
1691
1692 /**
1693  * proc_dointvec_minmax - read a vector of integers with min/max values
1694  * @table: the sysctl table
1695  * @write: %TRUE if this is a write to the sysctl file
1696  * @filp: the file structure
1697  * @buffer: the user buffer
1698  * @lenp: the size of the user buffer
1699  *
1700  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1701  * values from/to the user buffer, treated as an ASCII string.
1702  *
1703  * This routine will ensure the values are within the range specified by
1704  * table->extra1 (min) and table->extra2 (max).
1705  *
1706  * Returns 0 on success.
1707  */
1708 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1709                   void __user *buffer, size_t *lenp, loff_t *ppos)
1710 {
1711         struct do_proc_dointvec_minmax_conv_param param = {
1712                 .min = (int *) table->extra1,
1713                 .max = (int *) table->extra2,
1714         };
1715         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1716                                 do_proc_dointvec_minmax_conv, &param);
1717 }
1718
1719 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1720                                      struct file *filp,
1721                                      void __user *buffer,
1722                                      size_t *lenp, loff_t *ppos,
1723                                      unsigned long convmul,
1724                                      unsigned long convdiv)
1725 {
1726 #define TMPBUFLEN 21
1727         unsigned long *i, *min, *max, val;
1728         int vleft, first=1, neg;
1729         size_t len, left;
1730         char buf[TMPBUFLEN], *p;
1731         char __user *s = buffer;
1732
1733         if (!table->data || !table->maxlen || !*lenp ||
1734             (*ppos && !write)) {
1735                 *lenp = 0;
1736                 return 0;
1737         }
1738
1739         i = (unsigned long *) table->data;
1740         min = (unsigned long *) table->extra1;
1741         max = (unsigned long *) table->extra2;
1742         vleft = table->maxlen / sizeof(unsigned long);
1743         left = *lenp;
1744
1745         for (; left && vleft--; i++, min++, max++, first=0) {
1746                 if (write) {
1747                         while (left) {
1748                                 char c;
1749                                 if (get_user(c, s))
1750                                         return -EFAULT;
1751                                 if (!isspace(c))
1752                                         break;
1753                                 left--;
1754                                 s++;
1755                         }
1756                         if (!left)
1757                                 break;
1758                         neg = 0;
1759                         len = left;
1760                         if (len > TMPBUFLEN-1)
1761                                 len = TMPBUFLEN-1;
1762                         if (copy_from_user(buf, s, len))
1763                                 return -EFAULT;
1764                         buf[len] = 0;
1765                         p = buf;
1766                         if (*p == '-' && left > 1) {
1767                                 neg = 1;
1768                                 left--, p++;
1769                         }
1770                         if (*p < '0' || *p > '9')
1771                                 break;
1772                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1773                         len = p-buf;
1774                         if ((len < left) && *p && !isspace(*p))
1775                                 break;
1776                         if (neg)
1777                                 val = -val;
1778                         s += len;
1779                         left -= len;
1780
1781                         if(neg)
1782                                 continue;
1783                         if ((min && val < *min) || (max && val > *max))
1784                                 continue;
1785                         *i = val;
1786                 } else {
1787                         p = buf;
1788                         if (!first)
1789                                 *p++ = '\t';
1790                         sprintf(p, "%lu", convdiv * (*i) / convmul);
1791                         len = strlen(buf);
1792                         if (len > left)
1793                                 len = left;
1794                         if(copy_to_user(s, buf, len))
1795                                 return -EFAULT;
1796                         left -= len;
1797                         s += len;
1798                 }
1799         }
1800
1801         if (!write && !first && left) {
1802                 if(put_user('\n', s))
1803                         return -EFAULT;
1804                 left--, s++;
1805         }
1806         if (write) {
1807                 while (left) {
1808                         char c;
1809                         if (get_user(c, s++))
1810                                 return -EFAULT;
1811                         if (!isspace(c))
1812                                 break;
1813                         left--;
1814                 }
1815         }
1816         if (write && first)
1817                 return -EINVAL;
1818         *lenp -= left;
1819         *ppos += *lenp;
1820         return 0;
1821 #undef TMPBUFLEN
1822 }
1823
1824 /**
1825  * proc_doulongvec_minmax - read a vector of long integers with min/max values
1826  * @table: the sysctl table
1827  * @write: %TRUE if this is a write to the sysctl file
1828  * @filp: the file structure
1829  * @buffer: the user buffer
1830  * @lenp: the size of the user buffer
1831  *
1832  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1833  * values from/to the user buffer, treated as an ASCII string.
1834  *
1835  * This routine will ensure the values are within the range specified by
1836  * table->extra1 (min) and table->extra2 (max).
1837  *
1838  * Returns 0 on success.
1839  */
1840 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
1841                            void __user *buffer, size_t *lenp, loff_t *ppos)
1842 {
1843     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
1844 }
1845
1846 /**
1847  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
1848  * @table: the sysctl table
1849  * @write: %TRUE if this is a write to the sysctl file
1850  * @filp: the file structure
1851  * @buffer: the user buffer
1852  * @lenp: the size of the user buffer
1853  *
1854  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1855  * values from/to the user buffer, treated as an ASCII string. The values
1856  * are treated as milliseconds, and converted to jiffies when they are stored.
1857  *
1858  * This routine will ensure the values are within the range specified by
1859  * table->extra1 (min) and table->extra2 (max).
1860  *
1861  * Returns 0 on success.
1862  */
1863 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
1864                                       struct file *filp,
1865                                       void __user *buffer,
1866                                       size_t *lenp, loff_t *ppos)
1867 {
1868     return do_proc_doulongvec_minmax(table, write, filp, buffer,
1869                                      lenp, ppos, HZ, 1000l);
1870 }
1871
1872
1873 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
1874                                          int *valp,
1875                                          int write, void *data)
1876 {
1877         if (write) {
1878                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
1879         } else {
1880                 int val = *valp;
1881                 unsigned long lval;
1882                 if (val < 0) {
1883                         *negp = -1;
1884                         lval = (unsigned long)-val;
1885                 } else {
1886                         *negp = 0;
1887                         lval = (unsigned long)val;
1888                 }
1889                 *lvalp = lval / HZ;
1890         }
1891         return 0;
1892 }
1893
1894 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
1895                                                 int *valp,
1896                                                 int write, void *data)
1897 {
1898         if (write) {
1899                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
1900         } else {
1901                 int val = *valp;
1902                 unsigned long lval;
1903                 if (val < 0) {
1904                         *negp = -1;
1905                         lval = (unsigned long)-val;
1906                 } else {
1907                         *negp = 0;
1908                         lval = (unsigned long)val;
1909                 }
1910                 *lvalp = jiffies_to_clock_t(lval);
1911         }
1912         return 0;
1913 }
1914
1915 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
1916                                             int *valp,
1917                                             int write, void *data)
1918 {
1919         if (write) {
1920                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
1921         } else {
1922                 int val = *valp;
1923                 unsigned long lval;
1924                 if (val < 0) {
1925                         *negp = -1;
1926                         lval = (unsigned long)-val;
1927                 } else {
1928                         *negp = 0;
1929                         lval = (unsigned long)val;
1930                 }
1931                 *lvalp = jiffies_to_msecs(lval);
1932         }
1933         return 0;
1934 }
1935
1936 /**
1937  * proc_dointvec_jiffies - read a vector of integers as seconds
1938  * @table: the sysctl table
1939  * @write: %TRUE if this is a write to the sysctl file
1940  * @filp: the file structure
1941  * @buffer: the user buffer
1942  * @lenp: the size of the user buffer
1943  *
1944  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1945  * values from/to the user buffer, treated as an ASCII string.
1946  * The values read are assumed to be in seconds, and are converted into
1947  * jiffies.
1948  *
1949  * Returns 0 on success.
1950  */
1951 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
1952                           void __user *buffer, size_t *lenp, loff_t *ppos)
1953 {
1954     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1955                             do_proc_dointvec_jiffies_conv,NULL);
1956 }
1957
1958 /**
1959  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
1960  * @table: the sysctl table
1961  * @write: %TRUE if this is a write to the sysctl file
1962  * @filp: the file structure
1963  * @buffer: the user buffer
1964  * @lenp: the size of the user buffer
1965  *
1966  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1967  * values from/to the user buffer, treated as an ASCII string.
1968  * The values read are assumed to be in 1/USER_HZ seconds, and
1969  * are converted into jiffies.
1970  *
1971  * Returns 0 on success.
1972  */
1973 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
1974                                  void __user *buffer, size_t *lenp, loff_t *ppos)
1975 {
1976     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1977                             do_proc_dointvec_userhz_jiffies_conv,NULL);
1978 }
1979
1980 /**
1981  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
1982  * @table: the sysctl table
1983  * @write: %TRUE if this is a write to the sysctl file
1984  * @filp: the file structure
1985  * @buffer: the user buffer
1986  * @lenp: the size of the user buffer
1987  *
1988  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1989  * values from/to the user buffer, treated as an ASCII string.
1990  * The values read are assumed to be in 1/1000 seconds, and
1991  * are converted into jiffies.
1992  *
1993  * Returns 0 on success.
1994  */
1995 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
1996                              void __user *buffer, size_t *lenp, loff_t *ppos)
1997 {
1998         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1999                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2000 }
2001
2002 #else /* CONFIG_PROC_FS */
2003
2004 int proc_dostring(ctl_table *table, int write, struct file *filp,
2005                   void __user *buffer, size_t *lenp, loff_t *ppos)
2006 {
2007         return -ENOSYS;
2008 }
2009
2010 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
2011                             void __user *buffer, size_t *lenp, loff_t *ppos)
2012 {
2013         return -ENOSYS;
2014 }
2015
2016 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2017                   void __user *buffer, size_t *lenp, loff_t *ppos)
2018 {
2019         return -ENOSYS;
2020 }
2021
2022 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2023                         void __user *buffer, size_t *lenp, loff_t *ppos)
2024 {
2025         return -ENOSYS;
2026 }
2027
2028 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2029                     void __user *buffer, size_t *lenp, loff_t *ppos)
2030 {
2031         return -ENOSYS;
2032 }
2033
2034 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2035                     void __user *buffer, size_t *lenp, loff_t *ppos)
2036 {
2037         return -ENOSYS;
2038 }
2039
2040 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2041                     void __user *buffer, size_t *lenp, loff_t *ppos)
2042 {
2043         return -ENOSYS;
2044 }
2045
2046 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2047                              void __user *buffer, size_t *lenp, loff_t *ppos)
2048 {
2049         return -ENOSYS;
2050 }
2051
2052 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2053                     void __user *buffer, size_t *lenp, loff_t *ppos)
2054 {
2055         return -ENOSYS;
2056 }
2057
2058 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2059                                       struct file *filp,
2060                                       void __user *buffer,
2061                                       size_t *lenp, loff_t *ppos)
2062 {
2063     return -ENOSYS;
2064 }
2065
2066
2067 #endif /* CONFIG_PROC_FS */
2068
2069
2070 /*
2071  * General sysctl support routines
2072  */
2073
2074 /* The generic string strategy routine: */
2075 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2076                   void __user *oldval, size_t __user *oldlenp,
2077                   void __user *newval, size_t newlen, void **context)
2078 {
2079         size_t l, len;
2080
2081         if (!table->data || !table->maxlen)
2082                 return -ENOTDIR;
2083
2084         if (oldval && oldlenp) {
2085                 if (get_user(len, oldlenp))
2086                         return -EFAULT;
2087                 if (len) {
2088                         l = strlen(table->data);
2089                         if (len > l) len = l;
2090                         if (len >= table->maxlen)
2091                                 len = table->maxlen;
2092                         if(copy_to_user(oldval, table->data, len))
2093                                 return -EFAULT;
2094                         if(put_user(0, ((char __user *) oldval) + len))
2095                                 return -EFAULT;
2096                         if(put_user(len, oldlenp))
2097                                 return -EFAULT;
2098                 }
2099         }
2100         if (newval && newlen) {
2101                 len = newlen;
2102                 if (len > table->maxlen)
2103                         len = table->maxlen;
2104                 if(copy_from_user(table->data, newval, len))
2105                         return -EFAULT;
2106                 if (len == table->maxlen)
2107                         len--;
2108                 ((char *) table->data)[len] = 0;
2109         }
2110         return 0;
2111 }
2112
2113 /*
2114  * This function makes sure that all of the integers in the vector
2115  * are between the minimum and maximum values given in the arrays
2116  * table->extra1 and table->extra2, respectively.
2117  */
2118 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2119                 void __user *oldval, size_t __user *oldlenp,
2120                 void __user *newval, size_t newlen, void **context)
2121 {
2122
2123         if (newval && newlen) {
2124                 int __user *vec = (int __user *) newval;
2125                 int *min = (int *) table->extra1;
2126                 int *max = (int *) table->extra2;
2127                 size_t length;
2128                 int i;
2129
2130                 if (newlen % sizeof(int) != 0)
2131                         return -EINVAL;
2132
2133                 if (!table->extra1 && !table->extra2)
2134                         return 0;
2135
2136                 if (newlen > table->maxlen)
2137                         newlen = table->maxlen;
2138                 length = newlen / sizeof(int);
2139
2140                 for (i = 0; i < length; i++) {
2141                         int value;
2142                         if (get_user(value, vec + i))
2143                                 return -EFAULT;
2144                         if (min && value < min[i])
2145                                 return -EINVAL;
2146                         if (max && value > max[i])
2147                                 return -EINVAL;
2148                 }
2149         }
2150         return 0;
2151 }
2152
2153 /* Strategy function to convert jiffies to seconds */
2154 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2155                 void __user *oldval, size_t __user *oldlenp,
2156                 void __user *newval, size_t newlen, void **context)
2157 {
2158         if (oldval) {
2159                 size_t olen;
2160                 if (oldlenp) {
2161                         if (get_user(olen, oldlenp))
2162                                 return -EFAULT;
2163                         if (olen!=sizeof(int))
2164                                 return -EINVAL;
2165                 }
2166                 if (put_user(*(int *)(table->data)/HZ, (int __user *)oldval) ||
2167                     (oldlenp && put_user(sizeof(int),oldlenp)))
2168                         return -EFAULT;
2169         }
2170         if (newval && newlen) {
2171                 int new;
2172                 if (newlen != sizeof(int))
2173                         return -EINVAL;
2174                 if (get_user(new, (int __user *)newval))
2175                         return -EFAULT;
2176                 *(int *)(table->data) = new*HZ;
2177         }
2178         return 1;
2179 }
2180
2181 /* Strategy function to convert jiffies to seconds */
2182 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2183                 void __user *oldval, size_t __user *oldlenp,
2184                 void __user *newval, size_t newlen, void **context)
2185 {
2186         if (oldval) {
2187                 size_t olen;
2188                 if (oldlenp) {
2189                         if (get_user(olen, oldlenp))
2190                                 return -EFAULT;
2191                         if (olen!=sizeof(int))
2192                                 return -EINVAL;
2193                 }
2194                 if (put_user(jiffies_to_msecs(*(int *)(table->data)), (int __user *)oldval) ||
2195                     (oldlenp && put_user(sizeof(int),oldlenp)))
2196                         return -EFAULT;
2197         }
2198         if (newval && newlen) {
2199                 int new;
2200                 if (newlen != sizeof(int))
2201                         return -EINVAL;
2202                 if (get_user(new, (int __user *)newval))
2203                         return -EFAULT;
2204                 *(int *)(table->data) = msecs_to_jiffies(new);
2205         }
2206         return 1;
2207 }
2208
2209 #else /* CONFIG_SYSCTL */
2210
2211
2212 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2213 {
2214         return -ENOSYS;
2215 }
2216
2217 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2218                   void __user *oldval, size_t __user *oldlenp,
2219                   void __user *newval, size_t newlen, void **context)
2220 {
2221         return -ENOSYS;
2222 }
2223
2224 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2225                 void __user *oldval, size_t __user *oldlenp,
2226                 void __user *newval, size_t newlen, void **context)
2227 {
2228         return -ENOSYS;
2229 }
2230
2231 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2232                 void __user *oldval, size_t __user *oldlenp,
2233                 void __user *newval, size_t newlen, void **context)
2234 {
2235         return -ENOSYS;
2236 }
2237
2238 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2239                 void __user *oldval, size_t __user *oldlenp,
2240                 void __user *newval, size_t newlen, void **context)
2241 {
2242         return -ENOSYS;
2243 }
2244
2245 int proc_dostring(ctl_table *table, int write, struct file *filp,
2246                   void __user *buffer, size_t *lenp, loff_t *ppos)
2247 {
2248         return -ENOSYS;
2249 }
2250
2251 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2252                   void __user *buffer, size_t *lenp, loff_t *ppos)
2253 {
2254         return -ENOSYS;
2255 }
2256
2257 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2258                         void __user *buffer, size_t *lenp, loff_t *ppos)
2259 {
2260         return -ENOSYS;
2261 }
2262
2263 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2264                     void __user *buffer, size_t *lenp, loff_t *ppos)
2265 {
2266         return -ENOSYS;
2267 }
2268
2269 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2270                           void __user *buffer, size_t *lenp, loff_t *ppos)
2271 {
2272         return -ENOSYS;
2273 }
2274
2275 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2276                           void __user *buffer, size_t *lenp, loff_t *ppos)
2277 {
2278         return -ENOSYS;
2279 }
2280
2281 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2282                              void __user *buffer, size_t *lenp, loff_t *ppos)
2283 {
2284         return -ENOSYS;
2285 }
2286
2287 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2288                     void __user *buffer, size_t *lenp, loff_t *ppos)
2289 {
2290         return -ENOSYS;
2291 }
2292
2293 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2294                                       struct file *filp,
2295                                       void __user *buffer,
2296                                       size_t *lenp, loff_t *ppos)
2297 {
2298     return -ENOSYS;
2299 }
2300
2301 struct ctl_table_header * register_sysctl_table(ctl_table * table,
2302                                                 int insert_at_head)
2303 {
2304         return NULL;
2305 }
2306
2307 void unregister_sysctl_table(struct ctl_table_header * table)
2308 {
2309 }
2310
2311 #endif /* CONFIG_SYSCTL */
2312
2313 /*
2314  * No sense putting this after each symbol definition, twice,
2315  * exception granted :-)
2316  */
2317 EXPORT_SYMBOL(proc_dointvec);
2318 EXPORT_SYMBOL(proc_dointvec_jiffies);
2319 EXPORT_SYMBOL(proc_dointvec_minmax);
2320 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2321 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2322 EXPORT_SYMBOL(proc_dostring);
2323 EXPORT_SYMBOL(proc_doulongvec_minmax);
2324 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2325 EXPORT_SYMBOL(register_sysctl_table);
2326 EXPORT_SYMBOL(sysctl_intvec);
2327 EXPORT_SYMBOL(sysctl_jiffies);
2328 EXPORT_SYMBOL(sysctl_ms_jiffies);
2329 EXPORT_SYMBOL(sysctl_string);
2330 EXPORT_SYMBOL(unregister_sysctl_table);