kernel/sysctl.c

   1 /*
   2  * sysctl.c: General linux system control interface
   3  *
   4  * Begun 24 March 1995, Stephen Tweedie
   5  * Added /proc support, Dec 1995
   6  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
   7  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
   8  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
   9  * Dynamic registration fixes, Stephen Tweedie.
  10  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
  11  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
  12  *  Horn.
  13  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
  14  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
  15  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
  16  *  Wendling.
  17  * The list_for_each() macro wasn't appropriate for the sysctl loop.
  18  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
  19  */
  20
  21 #include <linux/config.h>
  22 #include <linux/module.h>
  23 #include <linux/mm.h>
  24 #include <linux/swap.h>
  25 #include <linux/slab.h>
  26 #include <linux/sysctl.h>
  27 #include <linux/proc_fs.h>
  28 #include <linux/ctype.h>
  29 #include <linux/utsname.h>
  30 #include <linux/capability.h>
  31 #include <linux/smp_lock.h>
  32 #include <linux/init.h>
  33 #include <linux/kernel.h>
  34 #include <linux/sysrq.h>
  35 #include <linux/highuid.h>
  36 #include <linux/writeback.h>
  37 #include <linux/hugetlb.h>
  38 #include <linux/security.h>
  39 #include <linux/initrd.h>
  40 #include <linux/times.h>
  41 #include <linux/limits.h>
  42 #include <linux/dcache.h>
  43 #include <linux/syscalls.h>
  44
  45 #include <asm/uaccess.h>
  46 #include <asm/processor.h>
  47
  48 #ifdef CONFIG_ROOT_NFS
  49 #include <linux/nfs_fs.h>
  50 #endif
  51
  52 #if defined(CONFIG_SYSCTL)
  53
  54 /* External variables not in a header file. */
  55 extern int C_A_D;
  56 extern int sysctl_overcommit_memory;
  57 extern int sysctl_overcommit_ratio;
  58 extern int max_threads;
  59 extern int sysrq_enabled;
  60 extern int core_uses_pid;
  61 extern int suid_dumpable;
  62 extern char core_pattern[];
  63 extern int cad_pid;
  64 extern int pid_max;
  65 extern int min_free_kbytes;
  66 extern int printk_ratelimit_jiffies;
  67 extern int printk_ratelimit_burst;
  68 extern int pid_max_min, pid_max_max;
  69
  70 #ifdef CONFIG_INOTIFY
  71 extern int inotify_max_user_devices;
  72 extern int inotify_max_user_watches;
  73 extern int inotify_max_queued_events;
  74 #endif
  75
  76 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
  77 int unknown_nmi_panic;
  78 extern int proc_unknown_nmi_panic(ctl_table *, int, struct file *,
  79                                   void __user *, size_t *, loff_t *);
  80 #endif
  81
  82 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
  83 static int maxolduid = 65535;
  84 static int minolduid;
  85
  86 static int ngroups_max = NGROUPS_MAX;
  87
  88 #ifdef CONFIG_KMOD
  89 extern char modprobe_path[];
  90 #endif
  91 #ifdef CONFIG_HOTPLUG
  92 extern char hotplug_path[];
  93 #endif
  94 #ifdef CONFIG_CHR_DEV_SG
  95 extern int sg_big_buff;
  96 #endif
  97 #ifdef CONFIG_SYSVIPC
  98 extern size_t shm_ctlmax;
  99 extern size_t shm_ctlall;
 100 extern int shm_ctlmni;
 101 extern int msg_ctlmax;
 102 extern int msg_ctlmnb;
 103 extern int msg_ctlmni;
 104 extern int sem_ctls[];
 105 #endif
 106
 107 #ifdef __sparc__
 108 extern char reboot_command [];
 109 extern int stop_a_enabled;
 110 extern int scons_pwroff;
 111 #endif
 112
 113 #ifdef __hppa__
 114 extern int pwrsw_enabled;
 115 extern int unaligned_enabled;
 116 #endif
 117
 118 #ifdef CONFIG_ARCH_S390
 119 #ifdef CONFIG_MATHEMU
 120 extern int sysctl_ieee_emulation_warnings;
 121 #endif
 122 extern int sysctl_userprocess_debug;
 123 #endif
 124
 125 extern int sysctl_hz_timer;
 126
 127 #ifdef CONFIG_BSD_PROCESS_ACCT
 128 extern int acct_parm[];
 129 #endif
 130
 131 int randomize_va_space = 1;
 132
 133 static int parse_table(int __user *, int, void __user *, size_t __user *, void __user *, size_t,
 134                        ctl_table *, void **);
 135 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
 136                   void __user *buffer, size_t *lenp, loff_t *ppos);
 137
 138 static ctl_table root_table[];
 139 static struct ctl_table_header root_table_header =
 140         { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
 141
 142 static ctl_table kern_table[];
 143 static ctl_table vm_table[];
 144 #ifdef CONFIG_NET
 145 extern ctl_table net_table[];
 146 #endif
 147 static ctl_table proc_table[];
 148 static ctl_table fs_table[];
 149 static ctl_table debug_table[];
 150 static ctl_table dev_table[];
 151 extern ctl_table random_table[];
 152 #ifdef CONFIG_UNIX98_PTYS
 153 extern ctl_table pty_table[];
 154 #endif
 155
 156 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 157 int sysctl_legacy_va_layout;
 158 #endif
 159
 160 /* /proc declarations: */
 161
 162 #ifdef CONFIG_PROC_FS
 163
 164 static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
 165 static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
 166 static int proc_opensys(struct inode *, struct file *);
 167
 168 struct file_operations proc_sys_file_operations = {
 169         .open           = proc_opensys,
 170         .read           = proc_readsys,
 171         .write          = proc_writesys,
 172 };
 173
 174 extern struct proc_dir_entry *proc_sys_root;
 175
 176 static void register_proc_table(ctl_table *, struct proc_dir_entry *);
 177 static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
 178 #endif
 179
 180 /* The default sysctl tables: */
 181
 182 static ctl_table root_table[] = {
 183         {
 184                 .ctl_name       = CTL_KERN,
 185                 .procname       = "kernel",
 186                 .mode           = 0555,
 187                 .child          = kern_table,
 188         },
 189         {
 190                 .ctl_name       = CTL_VM,
 191                 .procname       = "vm",
 192                 .mode           = 0555,
 193                 .child          = vm_table,
 194         },
 195 #ifdef CONFIG_NET
 196         {
 197                 .ctl_name       = CTL_NET,
 198                 .procname       = "net",
 199                 .mode           = 0555,
 200                 .child          = net_table,
 201         },
 202 #endif
 203         {
 204                 .ctl_name       = CTL_PROC,
 205                 .procname       = "proc",
 206                 .mode           = 0555,
 207                 .child          = proc_table,
 208         },
 209         {
 210                 .ctl_name       = CTL_FS,
 211                 .procname       = "fs",
 212                 .mode           = 0555,
 213                 .child          = fs_table,
 214         },
 215         {
 216                 .ctl_name       = CTL_DEBUG,
 217                 .procname       = "debug",
 218                 .mode           = 0555,
 219                 .child          = debug_table,
 220         },
 221         {
 222                 .ctl_name       = CTL_DEV,
 223                 .procname       = "dev",
 224                 .mode           = 0555,
 225                 .child          = dev_table,
 226         },
 227
 228         { .ctl_name = 0 }
 229 };
 230
 231 static ctl_table kern_table[] = {
 232         {
 233                 .ctl_name       = KERN_OSTYPE,
 234                 .procname       = "ostype",
 235                 .data           = system_utsname.sysname,
 236                 .maxlen         = sizeof(system_utsname.sysname),
 237                 .mode           = 0444,
 238                 .proc_handler   = &proc_doutsstring,
 239                 .strategy       = &sysctl_string,
 240         },
 241         {
 242                 .ctl_name       = KERN_OSRELEASE,
 243                 .procname       = "osrelease",
 244                 .data           = system_utsname.release,
 245                 .maxlen         = sizeof(system_utsname.release),
 246                 .mode           = 0444,
 247                 .proc_handler   = &proc_doutsstring,
 248                 .strategy       = &sysctl_string,
 249         },
 250         {
 251                 .ctl_name       = KERN_VERSION,
 252                 .procname       = "version",
 253                 .data           = system_utsname.version,
 254                 .maxlen         = sizeof(system_utsname.version),
 255                 .mode           = 0444,
 256                 .proc_handler   = &proc_doutsstring,
 257                 .strategy       = &sysctl_string,
 258         },
 259         {
 260                 .ctl_name       = KERN_NODENAME,
 261                 .procname       = "hostname",
 262                 .data           = system_utsname.nodename,
 263                 .maxlen         = sizeof(system_utsname.nodename),
 264                 .mode           = 0644,
 265                 .proc_handler   = &proc_doutsstring,
 266                 .strategy       = &sysctl_string,
 267         },
 268         {
 269                 .ctl_name       = KERN_DOMAINNAME,
 270                 .procname       = "domainname",
 271                 .data           = system_utsname.domainname,
 272                 .maxlen         = sizeof(system_utsname.domainname),
 273                 .mode           = 0644,
 274                 .proc_handler   = &proc_doutsstring,
 275                 .strategy       = &sysctl_string,
 276         },
 277         {
 278                 .ctl_name       = KERN_PANIC,
 279                 .procname       = "panic",
 280                 .data           = &panic_timeout,
 281                 .maxlen         = sizeof(int),
 282                 .mode           = 0644,
 283                 .proc_handler   = &proc_dointvec,
 284         },
 285         {
 286                 .ctl_name       = KERN_CORE_USES_PID,
 287                 .procname       = "core_uses_pid",
 288                 .data           = &core_uses_pid,
 289                 .maxlen         = sizeof(int),
 290                 .mode           = 0644,
 291                 .proc_handler   = &proc_dointvec,
 292         },
 293         {
 294                 .ctl_name       = KERN_CORE_PATTERN,
 295                 .procname       = "core_pattern",
 296                 .data           = core_pattern,
 297                 .maxlen         = 64,
 298                 .mode           = 0644,
 299                 .proc_handler   = &proc_dostring,
 300                 .strategy       = &sysctl_string,
 301         },
 302         {
 303                 .ctl_name       = KERN_TAINTED,
 304                 .procname       = "tainted",
 305                 .data           = &tainted,
 306                 .maxlen         = sizeof(int),
 307                 .mode           = 0444,
 308                 .proc_handler   = &proc_dointvec,
 309         },
 310         {
 311                 .ctl_name       = KERN_CAP_BSET,
 312                 .procname       = "cap-bound",
 313                 .data           = &cap_bset,
 314                 .maxlen         = sizeof(kernel_cap_t),
 315                 .mode           = 0600,
 316                 .proc_handler   = &proc_dointvec_bset,
 317         },
 318 #ifdef CONFIG_BLK_DEV_INITRD
 319         {
 320                 .ctl_name       = KERN_REALROOTDEV,
 321                 .procname       = "real-root-dev",
 322                 .data           = &real_root_dev,
 323                 .maxlen         = sizeof(int),
 324                 .mode           = 0644,
 325                 .proc_handler   = &proc_dointvec,
 326         },
 327 #endif
 328 #ifdef __sparc__
 329         {
 330                 .ctl_name       = KERN_SPARC_REBOOT,
 331                 .procname       = "reboot-cmd",
 332                 .data           = reboot_command,
 333                 .maxlen         = 256,
 334                 .mode           = 0644,
 335                 .proc_handler   = &proc_dostring,
 336                 .strategy       = &sysctl_string,
 337         },
 338         {
 339                 .ctl_name       = KERN_SPARC_STOP_A,
 340                 .procname       = "stop-a",
 341                 .data           = &stop_a_enabled,
 342                 .maxlen         = sizeof (int),
 343                 .mode           = 0644,
 344                 .proc_handler   = &proc_dointvec,
 345         },
 346         {
 347                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 348                 .procname       = "scons-poweroff",
 349                 .data           = &scons_pwroff,
 350                 .maxlen         = sizeof (int),
 351                 .mode           = 0644,
 352                 .proc_handler   = &proc_dointvec,
 353         },
 354 #endif
 355 #ifdef __hppa__
 356         {
 357                 .ctl_name       = KERN_HPPA_PWRSW,
 358                 .procname       = "soft-power",
 359                 .data           = &pwrsw_enabled,
 360                 .maxlen         = sizeof (int),
 361                 .mode           = 0644,
 362                 .proc_handler   = &proc_dointvec,
 363         },
 364         {
 365                 .ctl_name       = KERN_HPPA_UNALIGNED,
 366                 .procname       = "unaligned-trap",
 367                 .data           = &unaligned_enabled,
 368                 .maxlen         = sizeof (int),
 369                 .mode           = 0644,
 370                 .proc_handler   = &proc_dointvec,
 371         },
 372 #endif
 373         {
 374                 .ctl_name       = KERN_CTLALTDEL,
 375                 .procname       = "ctrl-alt-del",
 376                 .data           = &C_A_D,
 377                 .maxlen         = sizeof(int),
 378                 .mode           = 0644,
 379                 .proc_handler   = &proc_dointvec,
 380         },
 381         {
 382                 .ctl_name       = KERN_PRINTK,
 383                 .procname       = "printk",
 384                 .data           = &console_loglevel,
 385                 .maxlen         = 4*sizeof(int),
 386                 .mode           = 0644,
 387                 .proc_handler   = &proc_dointvec,
 388         },
 389 #ifdef CONFIG_KMOD
 390         {
 391                 .ctl_name       = KERN_MODPROBE,
 392                 .procname       = "modprobe",
 393                 .data           = &modprobe_path,
 394                 .maxlen         = KMOD_PATH_LEN,
 395                 .mode           = 0644,
 396                 .proc_handler   = &proc_dostring,
 397                 .strategy       = &sysctl_string,
 398         },
 399 #endif
 400 #ifdef CONFIG_HOTPLUG
 401         {
 402                 .ctl_name       = KERN_HOTPLUG,
 403                 .procname       = "hotplug",
 404                 .data           = &hotplug_path,
 405                 .maxlen         = HOTPLUG_PATH_LEN,
 406                 .mode           = 0644,
 407                 .proc_handler   = &proc_dostring,
 408                 .strategy       = &sysctl_string,
 409         },
 410 #endif
 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         {
 646                 .ctl_name       = KERN_RANDOMIZE,
 647                 .procname       = "randomize_va_space",
 648                 .data           = &randomize_va_space,
 649                 .maxlen         = sizeof(int),
 650                 .mode           = 0644,
 651                 .proc_handler   = &proc_dointvec,
 652         },
 653
 654         { .ctl_name = 0 }
 655 };
 656
 657 /* Constants for minimum and maximum testing in vm_table.
 658    We use these as one-element integer vectors. */
 659 static int zero;
 660 static int one_hundred = 100;
 661
 662
 663 static ctl_table vm_table[] = {
 664         {
 665                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
 666                 .procname       = "overcommit_memory",
 667                 .data           = &sysctl_overcommit_memory,
 668                 .maxlen         = sizeof(sysctl_overcommit_memory),
 669                 .mode           = 0644,
 670                 .proc_handler   = &proc_dointvec,
 671         },
 672         {
 673                 .ctl_name       = VM_OVERCOMMIT_RATIO,
 674                 .procname       = "overcommit_ratio",
 675                 .data           = &sysctl_overcommit_ratio,
 676                 .maxlen         = sizeof(sysctl_overcommit_ratio),
 677                 .mode           = 0644,
 678                 .proc_handler   = &proc_dointvec,
 679         },
 680         {
 681                 .ctl_name       = VM_PAGE_CLUSTER,
 682                 .procname       = "page-cluster",
 683                 .data           = &page_cluster,
 684                 .maxlen         = sizeof(int),
 685                 .mode           = 0644,
 686                 .proc_handler   = &proc_dointvec,
 687         },
 688         {
 689                 .ctl_name       = VM_DIRTY_BACKGROUND,
 690                 .procname       = "dirty_background_ratio",
 691                 .data           = &dirty_background_ratio,
 692                 .maxlen         = sizeof(dirty_background_ratio),
 693                 .mode           = 0644,
 694                 .proc_handler   = &proc_dointvec_minmax,
 695                 .strategy       = &sysctl_intvec,
 696                 .extra1         = &zero,
 697                 .extra2         = &one_hundred,
 698         },
 699         {
 700                 .ctl_name       = VM_DIRTY_RATIO,
 701                 .procname       = "dirty_ratio",
 702                 .data           = &vm_dirty_ratio,
 703                 .maxlen         = sizeof(vm_dirty_ratio),
 704                 .mode           = 0644,
 705                 .proc_handler   = &proc_dointvec_minmax,
 706                 .strategy       = &sysctl_intvec,
 707                 .extra1         = &zero,
 708                 .extra2         = &one_hundred,
 709         },
 710         {
 711                 .ctl_name       = VM_DIRTY_WB_CS,
 712                 .procname       = "dirty_writeback_centisecs",
 713                 .data           = &dirty_writeback_centisecs,
 714                 .maxlen         = sizeof(dirty_writeback_centisecs),
 715                 .mode           = 0644,
 716                 .proc_handler   = &dirty_writeback_centisecs_handler,
 717         },
 718         {
 719                 .ctl_name       = VM_DIRTY_EXPIRE_CS,
 720                 .procname       = "dirty_expire_centisecs",
 721                 .data           = &dirty_expire_centisecs,
 722                 .maxlen         = sizeof(dirty_expire_centisecs),
 723                 .mode           = 0644,
 724                 .proc_handler   = &proc_dointvec,
 725         },
 726         {
 727                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
 728                 .procname       = "nr_pdflush_threads",
 729                 .data           = &nr_pdflush_threads,
 730                 .maxlen         = sizeof nr_pdflush_threads,
 731                 .mode           = 0444 /* read-only*/,
 732                 .proc_handler   = &proc_dointvec,
 733         },
 734         {
 735                 .ctl_name       = VM_SWAPPINESS,
 736                 .procname       = "swappiness",
 737                 .data           = &vm_swappiness,
 738                 .maxlen         = sizeof(vm_swappiness),
 739                 .mode           = 0644,
 740                 .proc_handler   = &proc_dointvec_minmax,
 741                 .strategy       = &sysctl_intvec,
 742                 .extra1         = &zero,
 743                 .extra2         = &one_hundred,
 744         },
 745 #ifdef CONFIG_HUGETLB_PAGE
 746          {
 747                 .ctl_name       = VM_HUGETLB_PAGES,
 748                 .procname       = "nr_hugepages",
 749                 .data           = &max_huge_pages,
 750                 .maxlen         = sizeof(unsigned long),
 751                 .mode           = 0644,
 752                 .proc_handler   = &hugetlb_sysctl_handler,
 753                 .extra1         = (void *)&hugetlb_zero,
 754                 .extra2         = (void *)&hugetlb_infinity,
 755          },
 756          {
 757                 .ctl_name       = VM_HUGETLB_GROUP,
 758                 .procname       = "hugetlb_shm_group",
 759                 .data           = &sysctl_hugetlb_shm_group,
 760                 .maxlen         = sizeof(gid_t),
 761                 .mode           = 0644,
 762                 .proc_handler   = &proc_dointvec,
 763          },
 764 #endif
 765         {
 766                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
 767                 .procname       = "lowmem_reserve_ratio",
 768                 .data           = &sysctl_lowmem_reserve_ratio,
 769                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
 770                 .mode           = 0644,
 771                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
 772                 .strategy       = &sysctl_intvec,
 773         },
 774         {
 775                 .ctl_name       = VM_MIN_FREE_KBYTES,
 776                 .procname       = "min_free_kbytes",
 777                 .data           = &min_free_kbytes,
 778                 .maxlen         = sizeof(min_free_kbytes),
 779                 .mode           = 0644,
 780                 .proc_handler   = &min_free_kbytes_sysctl_handler,
 781                 .strategy       = &sysctl_intvec,
 782                 .extra1         = &zero,
 783         },
 784 #ifdef CONFIG_MMU
 785         {
 786                 .ctl_name       = VM_MAX_MAP_COUNT,
 787                 .procname       = "max_map_count",
 788                 .data           = &sysctl_max_map_count,
 789                 .maxlen         = sizeof(sysctl_max_map_count),
 790                 .mode           = 0644,
 791                 .proc_handler   = &proc_dointvec
 792         },
 793 #endif
 794         {
 795                 .ctl_name       = VM_LAPTOP_MODE,
 796                 .procname       = "laptop_mode",
 797                 .data           = &laptop_mode,
 798                 .maxlen         = sizeof(laptop_mode),
 799                 .mode           = 0644,
 800                 .proc_handler   = &proc_dointvec,
 801                 .strategy       = &sysctl_intvec,
 802                 .extra1         = &zero,
 803         },
 804         {
 805                 .ctl_name       = VM_BLOCK_DUMP,
 806                 .procname       = "block_dump",
 807                 .data           = &block_dump,
 808                 .maxlen         = sizeof(block_dump),
 809                 .mode           = 0644,
 810                 .proc_handler   = &proc_dointvec,
 811                 .strategy       = &sysctl_intvec,
 812                 .extra1         = &zero,
 813         },
 814         {
 815                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
 816                 .procname       = "vfs_cache_pressure",
 817                 .data           = &sysctl_vfs_cache_pressure,
 818                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
 819                 .mode           = 0644,
 820                 .proc_handler   = &proc_dointvec,
 821                 .strategy       = &sysctl_intvec,
 822                 .extra1         = &zero,
 823         },
 824 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 825         {
 826                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
 827                 .procname       = "legacy_va_layout",
 828                 .data           = &sysctl_legacy_va_layout,
 829                 .maxlen         = sizeof(sysctl_legacy_va_layout),
 830                 .mode           = 0644,
 831                 .proc_handler   = &proc_dointvec,
 832                 .strategy       = &sysctl_intvec,
 833                 .extra1         = &zero,
 834         },
 835 #endif
 836 #ifdef CONFIG_SWAP
 837         {
 838                 .ctl_name       = VM_SWAP_TOKEN_TIMEOUT,
 839                 .procname       = "swap_token_timeout",
 840                 .data           = &swap_token_default_timeout,
 841                 .maxlen         = sizeof(swap_token_default_timeout),
 842                 .mode           = 0644,
 843                 .proc_handler   = &proc_dointvec_jiffies,
 844                 .strategy       = &sysctl_jiffies,
 845         },
 846 #endif
 847         { .ctl_name = 0 }
 848 };
 849
 850 static ctl_table proc_table[] = {
 851         { .ctl_name = 0 }
 852 };
 853
 854 static ctl_table fs_table[] = {
 855         {
 856                 .ctl_name       = FS_NRINODE,
 857                 .procname       = "inode-nr",
 858                 .data           = &inodes_stat,
 859                 .maxlen         = 2*sizeof(int),
 860                 .mode           = 0444,
 861                 .proc_handler   = &proc_dointvec,
 862         },
 863         {
 864                 .ctl_name       = FS_STATINODE,
 865                 .procname       = "inode-state",
 866                 .data           = &inodes_stat,
 867                 .maxlen         = 7*sizeof(int),
 868                 .mode           = 0444,
 869                 .proc_handler   = &proc_dointvec,
 870         },
 871         {
 872                 .ctl_name       = FS_NRFILE,
 873                 .procname       = "file-nr",
 874                 .data           = &files_stat,
 875                 .maxlen         = 3*sizeof(int),
 876                 .mode           = 0444,
 877                 .proc_handler   = &proc_dointvec,
 878         },
 879         {
 880                 .ctl_name       = FS_MAXFILE,
 881                 .procname       = "file-max",
 882                 .data           = &files_stat.max_files,
 883                 .maxlen         = sizeof(int),
 884                 .mode           = 0644,
 885                 .proc_handler   = &proc_dointvec,
 886         },
 887         {
 888                 .ctl_name       = FS_DENTRY,
 889                 .procname       = "dentry-state",
 890                 .data           = &dentry_stat,
 891                 .maxlen         = 6*sizeof(int),
 892                 .mode           = 0444,
 893                 .proc_handler   = &proc_dointvec,
 894         },
 895         {
 896                 .ctl_name       = FS_OVERFLOWUID,
 897                 .procname       = "overflowuid",
 898                 .data           = &fs_overflowuid,
 899                 .maxlen         = sizeof(int),
 900                 .mode           = 0644,
 901                 .proc_handler   = &proc_dointvec_minmax,
 902                 .strategy       = &sysctl_intvec,
 903                 .extra1         = &minolduid,
 904                 .extra2         = &maxolduid,
 905         },
 906         {
 907                 .ctl_name       = FS_OVERFLOWGID,
 908                 .procname       = "overflowgid",
 909                 .data           = &fs_overflowgid,
 910                 .maxlen         = sizeof(int),
 911                 .mode           = 0644,
 912                 .proc_handler   = &proc_dointvec_minmax,
 913                 .strategy       = &sysctl_intvec,
 914                 .extra1         = &minolduid,
 915                 .extra2         = &maxolduid,
 916         },
 917         {
 918                 .ctl_name       = FS_LEASES,
 919                 .procname       = "leases-enable",
 920                 .data           = &leases_enable,
 921                 .maxlen         = sizeof(int),
 922                 .mode           = 0644,
 923                 .proc_handler   = &proc_dointvec,
 924         },
 925 #ifdef CONFIG_DNOTIFY
 926         {
 927                 .ctl_name       = FS_DIR_NOTIFY,
 928                 .procname       = "dir-notify-enable",
 929                 .data           = &dir_notify_enable,
 930                 .maxlen         = sizeof(int),
 931                 .mode           = 0644,
 932                 .proc_handler   = &proc_dointvec,
 933         },
 934 #endif
 935 #ifdef CONFIG_MMU
 936         {
 937                 .ctl_name       = FS_LEASE_TIME,
 938                 .procname       = "lease-break-time",
 939                 .data           = &lease_break_time,
 940                 .maxlen         = sizeof(int),
 941                 .mode           = 0644,
 942                 .proc_handler   = &proc_dointvec,
 943         },
 944         {
 945                 .ctl_name       = FS_AIO_NR,
 946                 .procname       = "aio-nr",
 947                 .data           = &aio_nr,
 948                 .maxlen         = sizeof(aio_nr),
 949                 .mode           = 0444,
 950                 .proc_handler   = &proc_dointvec,
 951         },
 952         {
 953                 .ctl_name       = FS_AIO_MAX_NR,
 954                 .procname       = "aio-max-nr",
 955                 .data           = &aio_max_nr,
 956                 .maxlen         = sizeof(aio_max_nr),
 957                 .mode           = 0644,
 958                 .proc_handler   = &proc_dointvec,
 959         },
 960 #endif
 961         {
 962                 .ctl_name       = KERN_SETUID_DUMPABLE,
 963                 .procname       = "suid_dumpable",
 964                 .data           = &suid_dumpable,
 965                 .maxlen         = sizeof(int),
 966                 .mode           = 0644,
 967                 .proc_handler   = &proc_dointvec,
 968         },
 969 #ifdef CONFIG_INOTIFY
 970         {
 971                 .ctl_name       = INOTIFY_MAX_USER_DEVICES,
 972                 .procname       = "max_user_devices",
 973                 .data           = &inotify_max_user_devices,
 974                 .maxlen         = sizeof(int),
 975                 .mode           = 0644,
 976                 .proc_handler   = &proc_dointvec_minmax,
 977                 .strategy       = &sysctl_intvec,
 978                 .extra1         = &zero,
 979         },
 980
 981         {
 982                 .ctl_name       = INOTIFY_MAX_USER_WATCHES,
 983                 .procname       = "max_user_watches",
 984                 .data           = &inotify_max_user_watches,
 985                 .maxlen         = sizeof(int),
 986                 .mode           = 0644,
 987                 .proc_handler   = &proc_dointvec_minmax,
 988                 .strategy       = &sysctl_intvec,
 989                 .extra1         = &zero,
 990         },
 991
 992         {
 993                 .ctl_name       = INOTIFY_MAX_QUEUED_EVENTS,
 994                 .procname       = "max_queued_events",
 995                 .data           = &inotify_max_queued_events,
 996                 .maxlen         = sizeof(int),
 997                 .mode           = 0644,
 998                 .proc_handler   = &proc_dointvec_minmax,
 999                 .strategy       = &sysctl_intvec,
1000                 .extra1         = &zero
1001         },
1002 #endif
1003         { .ctl_name = 0 }
1004 };
1005
1006 static ctl_table debug_table[] = {
1007         { .ctl_name = 0 }
1008 };
1009
1010 static ctl_table dev_table[] = {
1011         { .ctl_name = 0 }
1012 };
1013
1014 extern void init_irq_proc (void);
1015
1016 void __init sysctl_init(void)
1017 {
1018 #ifdef CONFIG_PROC_FS
1019         register_proc_table(root_table, proc_sys_root);
1020         init_irq_proc();
1021 #endif
1022 }
1023
1024 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1025                void __user *newval, size_t newlen)
1026 {
1027         struct list_head *tmp;
1028
1029         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1030                 return -ENOTDIR;
1031         if (oldval) {
1032                 int old_len;
1033                 if (!oldlenp || get_user(old_len, oldlenp))
1034                         return -EFAULT;
1035         }
1036         tmp = &root_table_header.ctl_entry;
1037         do {
1038                 struct ctl_table_header *head =
1039                         list_entry(tmp, struct ctl_table_header, ctl_entry);
1040                 void *context = NULL;
1041                 int error = parse_table(name, nlen, oldval, oldlenp,
1042                                         newval, newlen, head->ctl_table,
1043                                         &context);
1044                 kfree(context);
1045                 if (error != -ENOTDIR)
1046                         return error;
1047                 tmp = tmp->next;
1048         } while (tmp != &root_table_header.ctl_entry);
1049         return -ENOTDIR;
1050 }
1051
1052 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1053 {
1054         struct __sysctl_args tmp;
1055         int error;
1056
1057         if (copy_from_user(&tmp, args, sizeof(tmp)))
1058                 return -EFAULT;
1059
1060         lock_kernel();
1061         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1062                           tmp.newval, tmp.newlen);
1063         unlock_kernel();
1064         return error;
1065 }
1066
1067 /*
1068  * ctl_perm does NOT grant the superuser all rights automatically, because
1069  * some sysctl variables are readonly even to root.
1070  */
1071
1072 static int test_perm(int mode, int op)
1073 {
1074         if (!current->euid)
1075                 mode >>= 6;
1076         else if (in_egroup_p(0))
1077                 mode >>= 3;
1078         if ((mode & op & 0007) == op)
1079                 return 0;
1080         return -EACCES;
1081 }
1082
1083 static inline int ctl_perm(ctl_table *table, int op)
1084 {
1085         int error;
1086         error = security_sysctl(table, op);
1087         if (error)
1088                 return error;
1089         return test_perm(table->mode, op);
1090 }
1091
1092 static int parse_table(int __user *name, int nlen,
1093                        void __user *oldval, size_t __user *oldlenp,
1094                        void __user *newval, size_t newlen,
1095                        ctl_table *table, void **context)
1096 {
1097         int n;
1098 repeat:
1099         if (!nlen)
1100                 return -ENOTDIR;
1101         if (get_user(n, name))
1102                 return -EFAULT;
1103         for ( ; table->ctl_name; table++) {
1104                 if (n == table->ctl_name || table->ctl_name == CTL_ANY) {
1105                         int error;
1106                         if (table->child) {
1107                                 if (ctl_perm(table, 001))
1108                                         return -EPERM;
1109                                 if (table->strategy) {
1110                                         error = table->strategy(
1111                                                 table, name, nlen,
1112                                                 oldval, oldlenp,
1113                                                 newval, newlen, context);
1114                                         if (error)
1115                                                 return error;
1116                                 }
1117                                 name++;
1118                                 nlen--;
1119                                 table = table->child;
1120                                 goto repeat;
1121                         }
1122                         error = do_sysctl_strategy(table, name, nlen,
1123                                                    oldval, oldlenp,
1124                                                    newval, newlen, context);
1125                         return error;
1126                 }
1127         }
1128         return -ENOTDIR;
1129 }
1130
1131 /* Perform the actual read/write of a sysctl table entry. */
1132 int do_sysctl_strategy (ctl_table *table,
1133                         int __user *name, int nlen,
1134                         void __user *oldval, size_t __user *oldlenp,
1135                         void __user *newval, size_t newlen, void **context)
1136 {
1137         int op = 0, rc;
1138         size_t len;
1139
1140         if (oldval)
1141                 op |= 004;
1142         if (newval)
1143                 op |= 002;
1144         if (ctl_perm(table, op))
1145                 return -EPERM;
1146
1147         if (table->strategy) {
1148                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1149                                      newval, newlen, context);
1150                 if (rc < 0)
1151                         return rc;
1152                 if (rc > 0)
1153                         return 0;
1154         }
1155
1156         /* If there is no strategy routine, or if the strategy returns
1157          * zero, proceed with automatic r/w */
1158         if (table->data && table->maxlen) {
1159                 if (oldval && oldlenp) {
1160                         if (get_user(len, oldlenp))
1161                                 return -EFAULT;
1162                         if (len) {
1163                                 if (len > table->maxlen)
1164                                         len = table->maxlen;
1165                                 if(copy_to_user(oldval, table->data, len))
1166                                         return -EFAULT;
1167                                 if(put_user(len, oldlenp))
1168                                         return -EFAULT;
1169                         }
1170                 }
1171                 if (newval && newlen) {
1172                         len = newlen;
1173                         if (len > table->maxlen)
1174                                 len = table->maxlen;
1175                         if(copy_from_user(table->data, newval, len))
1176                                 return -EFAULT;
1177                 }
1178         }
1179         return 0;
1180 }
1181
1182 /**
1183  * register_sysctl_table - register a sysctl hierarchy
1184  * @table: the top-level table structure
1185  * @insert_at_head: whether the entry should be inserted in front or at the end
1186  *
1187  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1188  * array. An entry with a ctl_name of 0 terminates the table.
1189  *
1190  * The members of the &ctl_table structure are used as follows:
1191  *
1192  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1193  *            must be unique within that level of sysctl
1194  *
1195  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1196  *            enter a sysctl file
1197  *
1198  * data - a pointer to data for use by proc_handler
1199  *
1200  * maxlen - the maximum size in bytes of the data
1201  *
1202  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1203  *
1204  * child - a pointer to the child sysctl table if this entry is a directory, or
1205  *         %NULL.
1206  *
1207  * proc_handler - the text handler routine (described below)
1208  *
1209  * strategy - the strategy routine (described below)
1210  *
1211  * de - for internal use by the sysctl routines
1212  *
1213  * extra1, extra2 - extra pointers usable by the proc handler routines
1214  *
1215  * Leaf nodes in the sysctl tree will be represented by a single file
1216  * under /proc; non-leaf nodes will be represented by directories.
1217  *
1218  * sysctl(2) can automatically manage read and write requests through
1219  * the sysctl table.  The data and maxlen fields of the ctl_table
1220  * struct enable minimal validation of the values being written to be
1221  * performed, and the mode field allows minimal authentication.
1222  *
1223  * More sophisticated management can be enabled by the provision of a
1224  * strategy routine with the table entry.  This will be called before
1225  * any automatic read or write of the data is performed.
1226  *
1227  * The strategy routine may return
1228  *
1229  * < 0 - Error occurred (error is passed to user process)
1230  *
1231  * 0   - OK - proceed with automatic read or write.
1232  *
1233  * > 0 - OK - read or write has been done by the strategy routine, so
1234  *       return immediately.
1235  *
1236  * There must be a proc_handler routine for any terminal nodes
1237  * mirrored under /proc/sys (non-terminals are handled by a built-in
1238  * directory handler).  Several default handlers are available to
1239  * cover common cases -
1240  *
1241  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1242  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1243  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1244  *
1245  * It is the handler's job to read the input buffer from user memory
1246  * and process it. The handler should return 0 on success.
1247  *
1248  * This routine returns %NULL on a failure to register, and a pointer
1249  * to the table header on success.
1250  */
1251 struct ctl_table_header *register_sysctl_table(ctl_table * table,
1252                                                int insert_at_head)
1253 {
1254         struct ctl_table_header *tmp;
1255         tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1256         if (!tmp)
1257                 return NULL;
1258         tmp->ctl_table = table;
1259         INIT_LIST_HEAD(&tmp->ctl_entry);
1260         if (insert_at_head)
1261                 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
1262         else
1263                 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1264 #ifdef CONFIG_PROC_FS
1265         register_proc_table(table, proc_sys_root);
1266 #endif
1267         return tmp;
1268 }
1269
1270 /**
1271  * unregister_sysctl_table - unregister a sysctl table hierarchy
1272  * @header: the header returned from register_sysctl_table
1273  *
1274  * Unregisters the sysctl table and all children. proc entries may not
1275  * actually be removed until they are no longer used by anyone.
1276  */
1277 void unregister_sysctl_table(struct ctl_table_header * header)
1278 {
1279         list_del(&header->ctl_entry);
1280 #ifdef CONFIG_PROC_FS
1281         unregister_proc_table(header->ctl_table, proc_sys_root);
1282 #endif
1283         kfree(header);
1284 }
1285
1286 /*
1287  * /proc/sys support
1288  */
1289
1290 #ifdef CONFIG_PROC_FS
1291
1292 /* Scan the sysctl entries in table and add them all into /proc */
1293 static void register_proc_table(ctl_table * table, struct proc_dir_entry *root)
1294 {
1295         struct proc_dir_entry *de;
1296         int len;
1297         mode_t mode;
1298
1299         for (; table->ctl_name; table++) {
1300                 /* Can't do anything without a proc name. */
1301                 if (!table->procname)
1302                         continue;
1303                 /* Maybe we can't do anything with it... */
1304                 if (!table->proc_handler && !table->child) {
1305                         printk(KERN_WARNING "SYSCTL: Can't register %s\n",
1306                                 table->procname);
1307                         continue;
1308                 }
1309
1310                 len = strlen(table->procname);
1311                 mode = table->mode;
1312
1313                 de = NULL;
1314                 if (table->proc_handler)
1315                         mode |= S_IFREG;
1316                 else {
1317                         mode |= S_IFDIR;
1318                         for (de = root->subdir; de; de = de->next) {
1319                                 if (proc_match(len, table->procname, de))
1320                                         break;
1321                         }
1322                         /* If the subdir exists already, de is non-NULL */
1323                 }
1324
1325                 if (!de) {
1326                         de = create_proc_entry(table->procname, mode, root);
1327                         if (!de)
1328                                 continue;
1329                         de->data = (void *) table;
1330                         if (table->proc_handler)
1331                                 de->proc_fops = &proc_sys_file_operations;
1332                 }
1333                 table->de = de;
1334                 if (de->mode & S_IFDIR)
1335                         register_proc_table(table->child, de);
1336         }
1337 }
1338
1339 /*
1340  * Unregister a /proc sysctl table and any subdirectories.
1341  */
1342 static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
1343 {
1344         struct proc_dir_entry *de;
1345         for (; table->ctl_name; table++) {
1346                 if (!(de = table->de))
1347                         continue;
1348                 if (de->mode & S_IFDIR) {
1349                         if (!table->child) {
1350                                 printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
1351                                 continue;
1352                         }
1353                         unregister_proc_table(table->child, de);
1354
1355                         /* Don't unregister directories which still have entries.. */
1356                         if (de->subdir)
1357                                 continue;
1358                 }
1359
1360                 /* Don't unregister proc entries that are still being used.. */
1361                 if (atomic_read(&de->count))
1362                         continue;
1363
1364                 table->de = NULL;
1365                 remove_proc_entry(table->procname, root);
1366         }
1367 }
1368
1369 static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
1370                           size_t count, loff_t *ppos)
1371 {
1372         int op;
1373         struct proc_dir_entry *de;
1374         struct ctl_table *table;
1375         size_t res;
1376         ssize_t error;
1377
1378         de = PDE(file->f_dentry->d_inode);
1379         if (!de || !de->data)
1380                 return -ENOTDIR;
1381         table = (struct ctl_table *) de->data;
1382         if (!table || !table->proc_handler)
1383                 return -ENOTDIR;
1384         op = (write ? 002 : 004);
1385         if (ctl_perm(table, op))
1386                 return -EPERM;
1387
1388         res = count;
1389
1390         error = (*table->proc_handler) (table, write, file, buf, &res, ppos);
1391         if (error)
1392                 return error;
1393         return res;
1394 }
1395
1396 static int proc_opensys(struct inode *inode, struct file *file)
1397 {
1398         if (file->f_mode & FMODE_WRITE) {
1399                 /*
1400                  * sysctl entries that are not writable,
1401                  * are _NOT_ writable, capabilities or not.
1402                  */
1403                 if (!(inode->i_mode & S_IWUSR))
1404                         return -EPERM;
1405         }
1406
1407         return 0;
1408 }
1409
1410 static ssize_t proc_readsys(struct file * file, char __user * buf,
1411                             size_t count, loff_t *ppos)
1412 {
1413         return do_rw_proc(0, file, buf, count, ppos);
1414 }
1415
1416 static ssize_t proc_writesys(struct file * file, const char __user * buf,
1417                              size_t count, loff_t *ppos)
1418 {
1419         return do_rw_proc(1, file, (char __user *) buf, count, ppos);
1420 }
1421
1422 /**
1423  * proc_dostring - read a string sysctl
1424  * @table: the sysctl table
1425  * @write: %TRUE if this is a write to the sysctl file
1426  * @filp: the file structure
1427  * @buffer: the user buffer
1428  * @lenp: the size of the user buffer
1429  * @ppos: file position
1430  *
1431  * Reads/writes a string from/to the user buffer. If the kernel
1432  * buffer provided is not large enough to hold the string, the
1433  * string is truncated. The copied string is %NULL-terminated.
1434  * If the string is being read by the user process, it is copied
1435  * and a newline '\n' is added. It is truncated if the buffer is
1436  * not large enough.
1437  *
1438  * Returns 0 on success.
1439  */
1440 int proc_dostring(ctl_table *table, int write, struct file *filp,
1441                   void __user *buffer, size_t *lenp, loff_t *ppos)
1442 {
1443         size_t len;
1444         char __user *p;
1445         char c;
1446
1447         if (!table->data || !table->maxlen || !*lenp ||
1448             (*ppos && !write)) {
1449                 *lenp = 0;
1450                 return 0;
1451         }
1452
1453         if (write) {
1454                 len = 0;
1455                 p = buffer;
1456                 while (len < *lenp) {
1457                         if (get_user(c, p++))
1458                                 return -EFAULT;
1459                         if (c == 0 || c == '\n')
1460                                 break;
1461                         len++;
1462                 }
1463                 if (len >= table->maxlen)
1464                         len = table->maxlen-1;
1465                 if(copy_from_user(table->data, buffer, len))
1466                         return -EFAULT;
1467                 ((char *) table->data)[len] = 0;
1468                 *ppos += *lenp;
1469         } else {
1470                 len = strlen(table->data);
1471                 if (len > table->maxlen)
1472                         len = table->maxlen;
1473                 if (len > *lenp)
1474                         len = *lenp;
1475                 if (len)
1476                         if(copy_to_user(buffer, table->data, len))
1477                                 return -EFAULT;
1478                 if (len < *lenp) {
1479                         if(put_user('\n', ((char __user *) buffer) + len))
1480                                 return -EFAULT;
1481                         len++;
1482                 }
1483                 *lenp = len;
1484                 *ppos += len;
1485         }
1486         return 0;
1487 }
1488
1489 /*
1490  *      Special case of dostring for the UTS structure. This has locks
1491  *      to observe. Should this be in kernel/sys.c ????
1492  */
1493
1494 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
1495                   void __user *buffer, size_t *lenp, loff_t *ppos)
1496 {
1497         int r;
1498
1499         if (!write) {
1500                 down_read(&uts_sem);
1501                 r=proc_dostring(table,0,filp,buffer,lenp, ppos);
1502                 up_read(&uts_sem);
1503         } else {
1504                 down_write(&uts_sem);
1505                 r=proc_dostring(table,1,filp,buffer,lenp, ppos);
1506                 up_write(&uts_sem);
1507         }
1508         return r;
1509 }
1510
1511 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1512                                  int *valp,
1513                                  int write, void *data)
1514 {
1515         if (write) {
1516                 *valp = *negp ? -*lvalp : *lvalp;
1517         } else {
1518                 int val = *valp;
1519                 if (val < 0) {
1520                         *negp = -1;
1521                         *lvalp = (unsigned long)-val;
1522                 } else {
1523                         *negp = 0;
1524                         *lvalp = (unsigned long)val;
1525                 }
1526         }
1527         return 0;
1528 }
1529
1530 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1531                   void __user *buffer, size_t *lenp, loff_t *ppos,
1532                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1533                               int write, void *data),
1534                   void *data)
1535 {
1536 #define TMPBUFLEN 21
1537         int *i, vleft, first=1, neg, val;
1538         unsigned long lval;
1539         size_t left, len;
1540
1541         char buf[TMPBUFLEN], *p;
1542         char __user *s = buffer;
1543
1544         if (!table->data || !table->maxlen || !*lenp ||
1545             (*ppos && !write)) {
1546                 *lenp = 0;
1547                 return 0;
1548         }
1549
1550         i = (int *) table->data;
1551         vleft = table->maxlen / sizeof(*i);
1552         left = *lenp;
1553
1554         if (!conv)
1555                 conv = do_proc_dointvec_conv;
1556
1557         for (; left && vleft--; i++, first=0) {
1558                 if (write) {
1559                         while (left) {
1560                                 char c;
1561                                 if (get_user(c, s))
1562                                         return -EFAULT;
1563                                 if (!isspace(c))
1564                                         break;
1565                                 left--;
1566                                 s++;
1567                         }
1568                         if (!left)
1569                                 break;
1570                         neg = 0;
1571                         len = left;
1572                         if (len > sizeof(buf) - 1)
1573                                 len = sizeof(buf) - 1;
1574                         if (copy_from_user(buf, s, len))
1575                                 return -EFAULT;
1576                         buf[len] = 0;
1577                         p = buf;
1578                         if (*p == '-' && left > 1) {
1579                                 neg = 1;
1580                                 left--, p++;
1581                         }
1582                         if (*p < '0' || *p > '9')
1583                                 break;
1584
1585                         lval = simple_strtoul(p, &p, 0);
1586
1587                         len = p-buf;
1588                         if ((len < left) && *p && !isspace(*p))
1589                                 break;
1590                         if (neg)
1591                                 val = -val;
1592                         s += len;
1593                         left -= len;
1594
1595                         if (conv(&neg, &lval, i, 1, data))
1596                                 break;
1597                 } else {
1598                         p = buf;
1599                         if (!first)
1600                                 *p++ = '\t';
1601
1602                         if (conv(&neg, &lval, i, 0, data))
1603                                 break;
1604
1605                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
1606                         len = strlen(buf);
1607                         if (len > left)
1608                                 len = left;
1609                         if(copy_to_user(s, buf, len))
1610                                 return -EFAULT;
1611                         left -= len;
1612                         s += len;
1613                 }
1614         }
1615
1616         if (!write && !first && left) {
1617                 if(put_user('\n', s))
1618                         return -EFAULT;
1619                 left--, s++;
1620         }
1621         if (write) {
1622                 while (left) {
1623                         char c;
1624                         if (get_user(c, s++))
1625                                 return -EFAULT;
1626                         if (!isspace(c))
1627                                 break;
1628                         left--;
1629                 }
1630         }
1631         if (write && first)
1632                 return -EINVAL;
1633         *lenp -= left;
1634         *ppos += *lenp;
1635         return 0;
1636 #undef TMPBUFLEN
1637 }
1638
1639 /**
1640  * proc_dointvec - read a vector of integers
1641  * @table: the sysctl table
1642  * @write: %TRUE if this is a write to the sysctl file
1643  * @filp: the file structure
1644  * @buffer: the user buffer
1645  * @lenp: the size of the user buffer
1646  * @ppos: file position
1647  *
1648  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1649  * values from/to the user buffer, treated as an ASCII string.
1650  *
1651  * Returns 0 on success.
1652  */
1653 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1654                      void __user *buffer, size_t *lenp, loff_t *ppos)
1655 {
1656     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1657                             NULL,NULL);
1658 }
1659
1660 #define OP_SET  0
1661 #define OP_AND  1
1662 #define OP_OR   2
1663 #define OP_MAX  3
1664 #define OP_MIN  4
1665
1666 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1667                                       int *valp,
1668                                       int write, void *data)
1669 {
1670         int op = *(int *)data;
1671         if (write) {
1672                 int val = *negp ? -*lvalp : *lvalp;
1673                 switch(op) {
1674                 case OP_SET:    *valp = val; break;
1675                 case OP_AND:    *valp &= val; break;
1676                 case OP_OR:     *valp |= val; break;
1677                 case OP_MAX:    if(*valp < val)
1678                                         *valp = val;
1679                                 break;
1680                 case OP_MIN:    if(*valp > val)
1681                                 *valp = val;
1682                                 break;
1683                 }
1684         } else {
1685                 int val = *valp;
1686                 if (val < 0) {
1687                         *negp = -1;
1688                         *lvalp = (unsigned long)-val;
1689                 } else {
1690                         *negp = 0;
1691                         *lvalp = (unsigned long)val;
1692                 }
1693         }
1694         return 0;
1695 }
1696
1697 /*
1698  *      init may raise the set.
1699  */
1700
1701 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1702                         void __user *buffer, size_t *lenp, loff_t *ppos)
1703 {
1704         int op;
1705
1706         if (!capable(CAP_SYS_MODULE)) {
1707                 return -EPERM;
1708         }
1709
1710         op = (current->pid == 1) ? OP_SET : OP_AND;
1711         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1712                                 do_proc_dointvec_bset_conv,&op);
1713 }
1714
1715 struct do_proc_dointvec_minmax_conv_param {
1716         int *min;
1717         int *max;
1718 };
1719
1720 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1721                                         int *valp,
1722                                         int write, void *data)
1723 {
1724         struct do_proc_dointvec_minmax_conv_param *param = data;
1725         if (write) {
1726                 int val = *negp ? -*lvalp : *lvalp;
1727                 if ((param->min && *param->min > val) ||
1728                     (param->max && *param->max < val))
1729                         return -EINVAL;
1730                 *valp = val;
1731         } else {
1732                 int val = *valp;
1733                 if (val < 0) {
1734                         *negp = -1;
1735                         *lvalp = (unsigned long)-val;
1736                 } else {
1737                         *negp = 0;
1738                         *lvalp = (unsigned long)val;
1739                 }
1740         }
1741         return 0;
1742 }
1743
1744 /**
1745  * proc_dointvec_minmax - read a vector of integers with min/max values
1746  * @table: the sysctl table
1747  * @write: %TRUE if this is a write to the sysctl file
1748  * @filp: the file structure
1749  * @buffer: the user buffer
1750  * @lenp: the size of the user buffer
1751  * @ppos: file position
1752  *
1753  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1754  * values from/to the user buffer, treated as an ASCII string.
1755  *
1756  * This routine will ensure the values are within the range specified by
1757  * table->extra1 (min) and table->extra2 (max).
1758  *
1759  * Returns 0 on success.
1760  */
1761 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1762                   void __user *buffer, size_t *lenp, loff_t *ppos)
1763 {
1764         struct do_proc_dointvec_minmax_conv_param param = {
1765                 .min = (int *) table->extra1,
1766                 .max = (int *) table->extra2,
1767         };
1768         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1769                                 do_proc_dointvec_minmax_conv, &param);
1770 }
1771
1772 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1773                                      struct file *filp,
1774                                      void __user *buffer,
1775                                      size_t *lenp, loff_t *ppos,
1776                                      unsigned long convmul,
1777                                      unsigned long convdiv)
1778 {
1779 #define TMPBUFLEN 21
1780         unsigned long *i, *min, *max, val;
1781         int vleft, first=1, neg;
1782         size_t len, left;
1783         char buf[TMPBUFLEN], *p;
1784         char __user *s = buffer;
1785
1786         if (!table->data || !table->maxlen || !*lenp ||
1787             (*ppos && !write)) {
1788                 *lenp = 0;
1789                 return 0;
1790         }
1791
1792         i = (unsigned long *) table->data;
1793         min = (unsigned long *) table->extra1;
1794         max = (unsigned long *) table->extra2;
1795         vleft = table->maxlen / sizeof(unsigned long);
1796         left = *lenp;
1797
1798         for (; left && vleft--; i++, min++, max++, first=0) {
1799                 if (write) {
1800                         while (left) {
1801                                 char c;
1802                                 if (get_user(c, s))
1803                                         return -EFAULT;
1804                                 if (!isspace(c))
1805                                         break;
1806                                 left--;
1807                                 s++;
1808                         }
1809                         if (!left)
1810                                 break;
1811                         neg = 0;
1812                         len = left;
1813                         if (len > TMPBUFLEN-1)
1814                                 len = TMPBUFLEN-1;
1815                         if (copy_from_user(buf, s, len))
1816                                 return -EFAULT;
1817                         buf[len] = 0;
1818                         p = buf;
1819                         if (*p == '-' && left > 1) {
1820                                 neg = 1;
1821                                 left--, p++;
1822                         }
1823                         if (*p < '0' || *p > '9')
1824                                 break;
1825                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1826                         len = p-buf;
1827                         if ((len < left) && *p && !isspace(*p))
1828                                 break;
1829                         if (neg)
1830                                 val = -val;
1831                         s += len;
1832                         left -= len;
1833
1834                         if(neg)
1835                                 continue;
1836                         if ((min && val < *min) || (max && val > *max))
1837                                 continue;
1838                         *i = val;
1839                 } else {
1840                         p = buf;
1841                         if (!first)
1842                                 *p++ = '\t';
1843                         sprintf(p, "%lu", convdiv * (*i) / convmul);
1844                         len = strlen(buf);
1845                         if (len > left)
1846                                 len = left;
1847                         if(copy_to_user(s, buf, len))
1848                                 return -EFAULT;
1849                         left -= len;
1850                         s += len;
1851                 }
1852         }
1853
1854         if (!write && !first && left) {
1855                 if(put_user('\n', s))
1856                         return -EFAULT;
1857                 left--, s++;
1858         }
1859         if (write) {
1860                 while (left) {
1861                         char c;
1862                         if (get_user(c, s++))
1863                                 return -EFAULT;
1864                         if (!isspace(c))
1865                                 break;
1866                         left--;
1867                 }
1868         }
1869         if (write && first)
1870                 return -EINVAL;
1871         *lenp -= left;
1872         *ppos += *lenp;
1873         return 0;
1874 #undef TMPBUFLEN
1875 }
1876
1877 /**
1878  * proc_doulongvec_minmax - read a vector of long integers with min/max values
1879  * @table: the sysctl table
1880  * @write: %TRUE if this is a write to the sysctl file
1881  * @filp: the file structure
1882  * @buffer: the user buffer
1883  * @lenp: the size of the user buffer
1884  * @ppos: file position
1885  *
1886  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1887  * values from/to the user buffer, treated as an ASCII string.
1888  *
1889  * This routine will ensure the values are within the range specified by
1890  * table->extra1 (min) and table->extra2 (max).
1891  *
1892  * Returns 0 on success.
1893  */
1894 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
1895                            void __user *buffer, size_t *lenp, loff_t *ppos)
1896 {
1897     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
1898 }
1899
1900 /**
1901  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
1902  * @table: the sysctl table
1903  * @write: %TRUE if this is a write to the sysctl file
1904  * @filp: the file structure
1905  * @buffer: the user buffer
1906  * @lenp: the size of the user buffer
1907  * @ppos: file position
1908  *
1909  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1910  * values from/to the user buffer, treated as an ASCII string. The values
1911  * are treated as milliseconds, and converted to jiffies when they are stored.
1912  *
1913  * This routine will ensure the values are within the range specified by
1914  * table->extra1 (min) and table->extra2 (max).
1915  *
1916  * Returns 0 on success.
1917  */
1918 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
1919                                       struct file *filp,
1920                                       void __user *buffer,
1921                                       size_t *lenp, loff_t *ppos)
1922 {
1923     return do_proc_doulongvec_minmax(table, write, filp, buffer,
1924                                      lenp, ppos, HZ, 1000l);
1925 }
1926
1927
1928 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
1929                                          int *valp,
1930                                          int write, void *data)
1931 {
1932         if (write) {
1933                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
1934         } else {
1935                 int val = *valp;
1936                 unsigned long lval;
1937                 if (val < 0) {
1938                         *negp = -1;
1939                         lval = (unsigned long)-val;
1940                 } else {
1941                         *negp = 0;
1942                         lval = (unsigned long)val;
1943                 }
1944                 *lvalp = lval / HZ;
1945         }
1946         return 0;
1947 }
1948
1949 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
1950                                                 int *valp,
1951                                                 int write, void *data)
1952 {
1953         if (write) {
1954                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
1955         } else {
1956                 int val = *valp;
1957                 unsigned long lval;
1958                 if (val < 0) {
1959                         *negp = -1;
1960                         lval = (unsigned long)-val;
1961                 } else {
1962                         *negp = 0;
1963                         lval = (unsigned long)val;
1964                 }
1965                 *lvalp = jiffies_to_clock_t(lval);
1966         }
1967         return 0;
1968 }
1969
1970 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
1971                                             int *valp,
1972                                             int write, void *data)
1973 {
1974         if (write) {
1975                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
1976         } else {
1977                 int val = *valp;
1978                 unsigned long lval;
1979                 if (val < 0) {
1980                         *negp = -1;
1981                         lval = (unsigned long)-val;
1982                 } else {
1983                         *negp = 0;
1984                         lval = (unsigned long)val;
1985                 }
1986                 *lvalp = jiffies_to_msecs(lval);
1987         }
1988         return 0;
1989 }
1990
1991 /**
1992  * proc_dointvec_jiffies - read a vector of integers as seconds
1993  * @table: the sysctl table
1994  * @write: %TRUE if this is a write to the sysctl file
1995  * @filp: the file structure
1996  * @buffer: the user buffer
1997  * @lenp: the size of the user buffer
1998  * @ppos: file position
1999  *
2000  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2001  * values from/to the user buffer, treated as an ASCII string.
2002  * The values read are assumed to be in seconds, and are converted into
2003  * jiffies.
2004  *
2005  * Returns 0 on success.
2006  */
2007 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2008                           void __user *buffer, size_t *lenp, loff_t *ppos)
2009 {
2010     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2011                             do_proc_dointvec_jiffies_conv,NULL);
2012 }
2013
2014 /**
2015  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2016  * @table: the sysctl table
2017  * @write: %TRUE if this is a write to the sysctl file
2018  * @filp: the file structure
2019  * @buffer: the user buffer
2020  * @lenp: the size of the user buffer
2021  *
2022  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2023  * values from/to the user buffer, treated as an ASCII string.
2024  * The values read are assumed to be in 1/USER_HZ seconds, and
2025  * are converted into jiffies.
2026  *
2027  * Returns 0 on success.
2028  */
2029 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2030                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2031 {
2032     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2033                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2034 }
2035
2036 /**
2037  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2038  * @table: the sysctl table
2039  * @write: %TRUE if this is a write to the sysctl file
2040  * @filp: the file structure
2041  * @buffer: the user buffer
2042  * @lenp: the size of the user buffer
2043  * @ppos: file position
2044  * @ppos: the current position in the file
2045  *
2046  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2047  * values from/to the user buffer, treated as an ASCII string.
2048  * The values read are assumed to be in 1/1000 seconds, and
2049  * are converted into jiffies.
2050  *
2051  * Returns 0 on success.
2052  */
2053 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2054                              void __user *buffer, size_t *lenp, loff_t *ppos)
2055 {
2056         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2057                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2058 }
2059
2060 #else /* CONFIG_PROC_FS */
2061
2062 int proc_dostring(ctl_table *table, int write, struct file *filp,
2063                   void __user *buffer, size_t *lenp, loff_t *ppos)
2064 {
2065         return -ENOSYS;
2066 }
2067
2068 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
2069                             void __user *buffer, size_t *lenp, loff_t *ppos)
2070 {
2071         return -ENOSYS;
2072 }
2073
2074 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2075                   void __user *buffer, size_t *lenp, loff_t *ppos)
2076 {
2077         return -ENOSYS;
2078 }
2079
2080 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2081                         void __user *buffer, size_t *lenp, loff_t *ppos)
2082 {
2083         return -ENOSYS;
2084 }
2085
2086 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2087                     void __user *buffer, size_t *lenp, loff_t *ppos)
2088 {
2089         return -ENOSYS;
2090 }
2091
2092 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2093                     void __user *buffer, size_t *lenp, loff_t *ppos)
2094 {
2095         return -ENOSYS;
2096 }
2097
2098 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2099                     void __user *buffer, size_t *lenp, loff_t *ppos)
2100 {
2101         return -ENOSYS;
2102 }
2103
2104 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2105                              void __user *buffer, size_t *lenp, loff_t *ppos)
2106 {
2107         return -ENOSYS;
2108 }
2109
2110 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2111                     void __user *buffer, size_t *lenp, loff_t *ppos)
2112 {
2113         return -ENOSYS;
2114 }
2115
2116 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2117                                       struct file *filp,
2118                                       void __user *buffer,
2119                                       size_t *lenp, loff_t *ppos)
2120 {
2121     return -ENOSYS;
2122 }
2123
2124
2125 #endif /* CONFIG_PROC_FS */
2126
2127
2128 /*
2129  * General sysctl support routines
2130  */
2131
2132 /* The generic string strategy routine: */
2133 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2134                   void __user *oldval, size_t __user *oldlenp,
2135                   void __user *newval, size_t newlen, void **context)
2136 {
2137         size_t l, len;
2138
2139         if (!table->data || !table->maxlen)
2140                 return -ENOTDIR;
2141
2142         if (oldval && oldlenp) {
2143                 if (get_user(len, oldlenp))
2144                         return -EFAULT;
2145                 if (len) {
2146                         l = strlen(table->data);
2147                         if (len > l) len = l;
2148                         if (len >= table->maxlen)
2149                                 len = table->maxlen;
2150                         if(copy_to_user(oldval, table->data, len))
2151                                 return -EFAULT;
2152                         if(put_user(0, ((char __user *) oldval) + len))
2153                                 return -EFAULT;
2154                         if(put_user(len, oldlenp))
2155                                 return -EFAULT;
2156                 }
2157         }
2158         if (newval && newlen) {
2159                 len = newlen;
2160                 if (len > table->maxlen)
2161                         len = table->maxlen;
2162                 if(copy_from_user(table->data, newval, len))
2163                         return -EFAULT;
2164                 if (len == table->maxlen)
2165                         len--;
2166                 ((char *) table->data)[len] = 0;
2167         }
2168         return 0;
2169 }
2170
2171 /*
2172  * This function makes sure that all of the integers in the vector
2173  * are between the minimum and maximum values given in the arrays
2174  * table->extra1 and table->extra2, respectively.
2175  */
2176 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2177                 void __user *oldval, size_t __user *oldlenp,
2178                 void __user *newval, size_t newlen, void **context)
2179 {
2180
2181         if (newval && newlen) {
2182                 int __user *vec = (int __user *) newval;
2183                 int *min = (int *) table->extra1;
2184                 int *max = (int *) table->extra2;
2185                 size_t length;
2186                 int i;
2187
2188                 if (newlen % sizeof(int) != 0)
2189                         return -EINVAL;
2190
2191                 if (!table->extra1 && !table->extra2)
2192                         return 0;
2193
2194                 if (newlen > table->maxlen)
2195                         newlen = table->maxlen;
2196                 length = newlen / sizeof(int);
2197
2198                 for (i = 0; i < length; i++) {
2199                         int value;
2200                         if (get_user(value, vec + i))
2201                                 return -EFAULT;
2202                         if (min && value < min[i])
2203                                 return -EINVAL;
2204                         if (max && value > max[i])
2205                                 return -EINVAL;
2206                 }
2207         }
2208         return 0;
2209 }
2210
2211 /* Strategy function to convert jiffies to seconds */
2212 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2213                 void __user *oldval, size_t __user *oldlenp,
2214                 void __user *newval, size_t newlen, void **context)
2215 {
2216         if (oldval) {
2217                 size_t olen;
2218                 if (oldlenp) {
2219                         if (get_user(olen, oldlenp))
2220                                 return -EFAULT;
2221                         if (olen!=sizeof(int))
2222                                 return -EINVAL;
2223                 }
2224                 if (put_user(*(int *)(table->data)/HZ, (int __user *)oldval) ||
2225                     (oldlenp && put_user(sizeof(int),oldlenp)))
2226                         return -EFAULT;
2227         }
2228         if (newval && newlen) {
2229                 int new;
2230                 if (newlen != sizeof(int))
2231                         return -EINVAL;
2232                 if (get_user(new, (int __user *)newval))
2233                         return -EFAULT;
2234                 *(int *)(table->data) = new*HZ;
2235         }
2236         return 1;
2237 }
2238
2239 /* Strategy function to convert jiffies to seconds */
2240 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2241                 void __user *oldval, size_t __user *oldlenp,
2242                 void __user *newval, size_t newlen, void **context)
2243 {
2244         if (oldval) {
2245                 size_t olen;
2246                 if (oldlenp) {
2247                         if (get_user(olen, oldlenp))
2248                                 return -EFAULT;
2249                         if (olen!=sizeof(int))
2250                                 return -EINVAL;
2251                 }
2252                 if (put_user(jiffies_to_msecs(*(int *)(table->data)), (int __user *)oldval) ||
2253                     (oldlenp && put_user(sizeof(int),oldlenp)))
2254                         return -EFAULT;
2255         }
2256         if (newval && newlen) {
2257                 int new;
2258                 if (newlen != sizeof(int))
2259                         return -EINVAL;
2260                 if (get_user(new, (int __user *)newval))
2261                         return -EFAULT;
2262                 *(int *)(table->data) = msecs_to_jiffies(new);
2263         }
2264         return 1;
2265 }
2266
2267 #else /* CONFIG_SYSCTL */
2268
2269
2270 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2271 {
2272         return -ENOSYS;
2273 }
2274
2275 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2276                   void __user *oldval, size_t __user *oldlenp,
2277                   void __user *newval, size_t newlen, void **context)
2278 {
2279         return -ENOSYS;
2280 }
2281
2282 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2283                 void __user *oldval, size_t __user *oldlenp,
2284                 void __user *newval, size_t newlen, void **context)
2285 {
2286         return -ENOSYS;
2287 }
2288
2289 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2290                 void __user *oldval, size_t __user *oldlenp,
2291                 void __user *newval, size_t newlen, void **context)
2292 {
2293         return -ENOSYS;
2294 }
2295
2296 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2297                 void __user *oldval, size_t __user *oldlenp,
2298                 void __user *newval, size_t newlen, void **context)
2299 {
2300         return -ENOSYS;
2301 }
2302
2303 int proc_dostring(ctl_table *table, int write, struct file *filp,
2304                   void __user *buffer, size_t *lenp, loff_t *ppos)
2305 {
2306         return -ENOSYS;
2307 }
2308
2309 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2310                   void __user *buffer, size_t *lenp, loff_t *ppos)
2311 {
2312         return -ENOSYS;
2313 }
2314
2315 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2316                         void __user *buffer, size_t *lenp, loff_t *ppos)
2317 {
2318         return -ENOSYS;
2319 }
2320
2321 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2322                     void __user *buffer, size_t *lenp, loff_t *ppos)
2323 {
2324         return -ENOSYS;
2325 }
2326
2327 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2328                           void __user *buffer, size_t *lenp, loff_t *ppos)
2329 {
2330         return -ENOSYS;
2331 }
2332
2333 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2334                           void __user *buffer, size_t *lenp, loff_t *ppos)
2335 {
2336         return -ENOSYS;
2337 }
2338
2339 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2340                              void __user *buffer, size_t *lenp, loff_t *ppos)
2341 {
2342         return -ENOSYS;
2343 }
2344
2345 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2346                     void __user *buffer, size_t *lenp, loff_t *ppos)
2347 {
2348         return -ENOSYS;
2349 }
2350
2351 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2352                                       struct file *filp,
2353                                       void __user *buffer,
2354                                       size_t *lenp, loff_t *ppos)
2355 {
2356     return -ENOSYS;
2357 }
2358
2359 struct ctl_table_header * register_sysctl_table(ctl_table * table,
2360                                                 int insert_at_head)
2361 {
2362         return NULL;
2363 }
2364
2365 void unregister_sysctl_table(struct ctl_table_header * table)
2366 {
2367 }
2368
2369 #endif /* CONFIG_SYSCTL */
2370
2371 /*
2372  * No sense putting this after each symbol definition, twice,
2373  * exception granted :-)
2374  */
2375 EXPORT_SYMBOL(proc_dointvec);
2376 EXPORT_SYMBOL(proc_dointvec_jiffies);
2377 EXPORT_SYMBOL(proc_dointvec_minmax);
2378 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2379 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2380 EXPORT_SYMBOL(proc_dostring);
2381 EXPORT_SYMBOL(proc_doulongvec_minmax);
2382 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2383 EXPORT_SYMBOL(register_sysctl_table);
2384 EXPORT_SYMBOL(sysctl_intvec);
2385 EXPORT_SYMBOL(sysctl_jiffies);
2386 EXPORT_SYMBOL(sysctl_ms_jiffies);
2387 EXPORT_SYMBOL(sysctl_string);
2388 EXPORT_SYMBOL(unregister_sysctl_table);