include/linux/sysctl.h

   1 /*
   2  * sysctl.h: General linux system control interface
   3  *
   4  * Begun 24 March 1995, Stephen Tweedie
   5  *
   6  ****************************************************************
   7  ****************************************************************
   8  **
   9  **  The values in this file are exported to user space via
  10  **  the sysctl() binary interface.  However this interface
  11  **  is unstable and deprecated and will be removed in the future.
  12  **  For a stable interface use /proc/sys.
  13  **
  14  ****************************************************************
  15  ****************************************************************
  16  */
  17
  18 #ifndef _LINUX_SYSCTL_H
  19 #define _LINUX_SYSCTL_H
  20
  21 #include <linux/kernel.h>
  22 #include <linux/types.h>
  23 #include <linux/compiler.h>
  24
  25 struct file;
  26 struct completion;
  27
  28 #define CTL_MAXNAME 10          /* how many path components do we allow in a
  29                                    call to sysctl?   In other words, what is
  30                                    the largest acceptable value for the nlen
  31                                    member of a struct __sysctl_args to have? */
  32
  33 struct __sysctl_args {
  34         int __user *name;
  35         int nlen;
  36         void __user *oldval;
  37         size_t __user *oldlenp;
  38         void __user *newval;
  39         size_t newlen;
  40         unsigned long __unused[4];
  41 };
  42
  43 /* Define sysctl names first */
  44
  45 /* Top-level names: */
  46
  47 /* For internal pattern-matching use only: */
  48 #ifdef __KERNEL__
  49 #define CTL_ANY         -1      /* Matches any name */
  50 #define CTL_NONE        0
  51 #endif
  52
  53 enum
  54 {
  55         CTL_KERN=1,             /* General kernel info and control */
  56         CTL_VM=2,               /* VM management */
  57         CTL_NET=3,              /* Networking */
  58         CTL_PROC=4,             /* Process info */
  59         CTL_FS=5,               /* Filesystems */
  60         CTL_DEBUG=6,            /* Debugging */
  61         CTL_DEV=7,              /* Devices */
  62         CTL_BUS=8,              /* Busses */
  63         CTL_ABI=9,              /* Binary emulation */
  64         CTL_CPU=10              /* CPU stuff (speed scaling, etc) */
  65 };
  66
  67 /* CTL_BUS names: */
  68 enum
  69 {
  70         CTL_BUS_ISA=1           /* ISA */
  71 };
  72
  73 /* /proc/sys/fs/inotify/ */
  74 enum
  75 {
  76         INOTIFY_MAX_USER_INSTANCES=1,   /* max instances per user */
  77         INOTIFY_MAX_USER_WATCHES=2,     /* max watches per user */
  78         INOTIFY_MAX_QUEUED_EVENTS=3     /* max queued events per instance */
  79 };
  80
  81 /* CTL_KERN names: */
  82 enum
  83 {
  84         KERN_OSTYPE=1,          /* string: system version */
  85         KERN_OSRELEASE=2,       /* string: system release */
  86         KERN_OSREV=3,           /* int: system revision */
  87         KERN_VERSION=4,         /* string: compile time info */
  88         KERN_SECUREMASK=5,      /* struct: maximum rights mask */
  89         KERN_PROF=6,            /* table: profiling information */
  90         KERN_NODENAME=7,
  91         KERN_DOMAINNAME=8,
  92
  93         KERN_CAP_BSET=14,       /* int: capability bounding set */
  94         KERN_PANIC=15,          /* int: panic timeout */
  95         KERN_REALROOTDEV=16,    /* real root device to mount after initrd */
  96
  97         KERN_SPARC_REBOOT=21,   /* reboot command on Sparc */
  98         KERN_CTLALTDEL=22,      /* int: allow ctl-alt-del to reboot */
  99         KERN_PRINTK=23,         /* struct: control printk logging parameters */
 100         KERN_NAMETRANS=24,      /* Name translation */
 101         KERN_PPC_HTABRECLAIM=25, /* turn htab reclaimation on/off on PPC */
 102         KERN_PPC_ZEROPAGED=26,  /* turn idle page zeroing on/off on PPC */
 103         KERN_PPC_POWERSAVE_NAP=27, /* use nap mode for power saving */
 104         KERN_MODPROBE=28,
 105         KERN_SG_BIG_BUFF=29,
 106         KERN_ACCT=30,           /* BSD process accounting parameters */
 107         KERN_PPC_L2CR=31,       /* l2cr register on PPC */
 108
 109         KERN_RTSIGNR=32,        /* Number of rt sigs queued */
 110         KERN_RTSIGMAX=33,       /* Max queuable */
 111
 112         KERN_SHMMAX=34,         /* long: Maximum shared memory segment */
 113         KERN_MSGMAX=35,         /* int: Maximum size of a messege */
 114         KERN_MSGMNB=36,         /* int: Maximum message queue size */
 115         KERN_MSGPOOL=37,        /* int: Maximum system message pool size */
 116         KERN_SYSRQ=38,          /* int: Sysreq enable */
 117         KERN_MAX_THREADS=39,    /* int: Maximum nr of threads in the system */
 118         KERN_RANDOM=40,         /* Random driver */
 119         KERN_SHMALL=41,         /* int: Maximum size of shared memory */
 120         KERN_MSGMNI=42,         /* int: msg queue identifiers */
 121         KERN_SEM=43,            /* struct: sysv semaphore limits */
 122         KERN_SPARC_STOP_A=44,   /* int: Sparc Stop-A enable */
 123         KERN_SHMMNI=45,         /* int: shm array identifiers */
 124         KERN_OVERFLOWUID=46,    /* int: overflow UID */
 125         KERN_OVERFLOWGID=47,    /* int: overflow GID */
 126         KERN_SHMPATH=48,        /* string: path to shm fs */
 127         KERN_HOTPLUG=49,        /* string: path to uevent helper (deprecated) */
 128         KERN_IEEE_EMULATION_WARNINGS=50, /* int: unimplemented ieee instructions */
 129         KERN_S390_USER_DEBUG_LOGGING=51,  /* int: dumps of user faults */
 130         KERN_CORE_USES_PID=52,          /* int: use core or core.%pid */
 131         KERN_TAINTED=53,        /* int: various kernel tainted flags */
 132         KERN_CADPID=54,         /* int: PID of the process to notify on CAD */
 133         KERN_PIDMAX=55,         /* int: PID # limit */
 134         KERN_CORE_PATTERN=56,   /* string: pattern for core-file names */
 135         KERN_PANIC_ON_OOPS=57,  /* int: whether we will panic on an oops */
 136         KERN_HPPA_PWRSW=58,     /* int: hppa soft-power enable */
 137         KERN_HPPA_UNALIGNED=59, /* int: hppa unaligned-trap enable */
 138         KERN_PRINTK_RATELIMIT=60, /* int: tune printk ratelimiting */
 139         KERN_PRINTK_RATELIMIT_BURST=61, /* int: tune printk ratelimiting */
 140         KERN_PTY=62,            /* dir: pty driver */
 141         KERN_NGROUPS_MAX=63,    /* int: NGROUPS_MAX */
 142         KERN_SPARC_SCONS_PWROFF=64, /* int: serial console power-off halt */
 143         KERN_HZ_TIMER=65,       /* int: hz timer on or off */
 144         KERN_UNKNOWN_NMI_PANIC=66, /* int: unknown nmi panic flag */
 145         KERN_BOOTLOADER_TYPE=67, /* int: boot loader type */
 146         KERN_RANDOMIZE=68, /* int: randomize virtual address space */
 147         KERN_SETUID_DUMPABLE=69, /* int: behaviour of dumps for setuid core */
 148         KERN_SPIN_RETRY=70,     /* int: number of spinlock retries */
 149         KERN_ACPI_VIDEO_FLAGS=71, /* int: flags for setting up video after ACPI sleep */
 150 };
 151
 152
 153 /* CTL_VM names: */
 154 enum
 155 {
 156         VM_UNUSED1=1,           /* was: struct: Set vm swapping control */
 157         VM_UNUSED2=2,           /* was; int: Linear or sqrt() swapout for hogs */
 158         VM_UNUSED3=3,           /* was: struct: Set free page thresholds */
 159         VM_UNUSED4=4,           /* Spare */
 160         VM_OVERCOMMIT_MEMORY=5, /* Turn off the virtual memory safety limit */
 161         VM_UNUSED5=6,           /* was: struct: Set buffer memory thresholds */
 162         VM_UNUSED7=7,           /* was: struct: Set cache memory thresholds */
 163         VM_UNUSED8=8,           /* was: struct: Control kswapd behaviour */
 164         VM_UNUSED9=9,           /* was: struct: Set page table cache parameters */
 165         VM_PAGE_CLUSTER=10,     /* int: set number of pages to swap together */
 166         VM_DIRTY_BACKGROUND=11, /* dirty_background_ratio */
 167         VM_DIRTY_RATIO=12,      /* dirty_ratio */
 168         VM_DIRTY_WB_CS=13,      /* dirty_writeback_centisecs */
 169         VM_DIRTY_EXPIRE_CS=14,  /* dirty_expire_centisecs */
 170         VM_NR_PDFLUSH_THREADS=15, /* nr_pdflush_threads */
 171         VM_OVERCOMMIT_RATIO=16, /* percent of RAM to allow overcommit in */
 172         VM_PAGEBUF=17,          /* struct: Control pagebuf parameters */
 173         VM_HUGETLB_PAGES=18,    /* int: Number of available Huge Pages */
 174         VM_SWAPPINESS=19,       /* Tendency to steal mapped memory */
 175         VM_LOWMEM_RESERVE_RATIO=20,/* reservation ratio for lower memory zones */
 176         VM_MIN_FREE_KBYTES=21,  /* Minimum free kilobytes to maintain */
 177         VM_MAX_MAP_COUNT=22,    /* int: Maximum number of mmaps/address-space */
 178         VM_LAPTOP_MODE=23,      /* vm laptop mode */
 179         VM_BLOCK_DUMP=24,       /* block dump mode */
 180         VM_HUGETLB_GROUP=25,    /* permitted hugetlb group */
 181         VM_VFS_CACHE_PRESSURE=26, /* dcache/icache reclaim pressure */
 182         VM_LEGACY_VA_LAYOUT=27, /* legacy/compatibility virtual address space layout */
 183         VM_SWAP_TOKEN_TIMEOUT=28, /* default time for token time out */
 184         VM_DROP_PAGECACHE=29,   /* int: nuke lots of pagecache */
 185         VM_PERCPU_PAGELIST_FRACTION=30,/* int: fraction of pages in each percpu_pagelist */
 186         VM_ZONE_RECLAIM_MODE=31, /* reclaim local zone memory before going off node */
 187         VM_ZONE_RECLAIM_INTERVAL=32, /* time period to wait after reclaim failure */
 188 };
 189
 190
 191 /* CTL_NET names: */
 192 enum
 193 {
 194         NET_CORE=1,
 195         NET_ETHER=2,
 196         NET_802=3,
 197         NET_UNIX=4,
 198         NET_IPV4=5,
 199         NET_IPX=6,
 200         NET_ATALK=7,
 201         NET_NETROM=8,
 202         NET_AX25=9,
 203         NET_BRIDGE=10,
 204         NET_ROSE=11,
 205         NET_IPV6=12,
 206         NET_X25=13,
 207         NET_TR=14,
 208         NET_DECNET=15,
 209         NET_ECONET=16,
 210         NET_SCTP=17,
 211         NET_LLC=18,
 212         NET_NETFILTER=19,
 213 };
 214
 215 /* /proc/sys/kernel/random */
 216 enum
 217 {
 218         RANDOM_POOLSIZE=1,
 219         RANDOM_ENTROPY_COUNT=2,
 220         RANDOM_READ_THRESH=3,
 221         RANDOM_WRITE_THRESH=4,
 222         RANDOM_BOOT_ID=5,
 223         RANDOM_UUID=6
 224 };
 225
 226 /* /proc/sys/kernel/pty */
 227 enum
 228 {
 229         PTY_MAX=1,
 230         PTY_NR=2
 231 };
 232
 233 /* /proc/sys/bus/isa */
 234 enum
 235 {
 236         BUS_ISA_MEM_BASE=1,
 237         BUS_ISA_PORT_BASE=2,
 238         BUS_ISA_PORT_SHIFT=3
 239 };
 240
 241 /* /proc/sys/net/core */
 242 enum
 243 {
 244         NET_CORE_WMEM_MAX=1,
 245         NET_CORE_RMEM_MAX=2,
 246         NET_CORE_WMEM_DEFAULT=3,
 247         NET_CORE_RMEM_DEFAULT=4,
 248 /* was  NET_CORE_DESTROY_DELAY */
 249         NET_CORE_MAX_BACKLOG=6,
 250         NET_CORE_FASTROUTE=7,
 251         NET_CORE_MSG_COST=8,
 252         NET_CORE_MSG_BURST=9,
 253         NET_CORE_OPTMEM_MAX=10,
 254         NET_CORE_HOT_LIST_LENGTH=11,
 255         NET_CORE_DIVERT_VERSION=12,
 256         NET_CORE_NO_CONG_THRESH=13,
 257         NET_CORE_NO_CONG=14,
 258         NET_CORE_LO_CONG=15,
 259         NET_CORE_MOD_CONG=16,
 260         NET_CORE_DEV_WEIGHT=17,
 261         NET_CORE_SOMAXCONN=18,
 262         NET_CORE_BUDGET=19,
 263 };
 264
 265 /* /proc/sys/net/ethernet */
 266
 267 /* /proc/sys/net/802 */
 268
 269 /* /proc/sys/net/unix */
 270
 271 enum
 272 {
 273         NET_UNIX_DESTROY_DELAY=1,
 274         NET_UNIX_DELETE_DELAY=2,
 275         NET_UNIX_MAX_DGRAM_QLEN=3,
 276 };
 277
 278 /* /proc/sys/net/netfilter */
 279 enum
 280 {
 281         NET_NF_CONNTRACK_MAX=1,
 282         NET_NF_CONNTRACK_TCP_TIMEOUT_SYN_SENT=2,
 283         NET_NF_CONNTRACK_TCP_TIMEOUT_SYN_RECV=3,
 284         NET_NF_CONNTRACK_TCP_TIMEOUT_ESTABLISHED=4,
 285         NET_NF_CONNTRACK_TCP_TIMEOUT_FIN_WAIT=5,
 286         NET_NF_CONNTRACK_TCP_TIMEOUT_CLOSE_WAIT=6,
 287         NET_NF_CONNTRACK_TCP_TIMEOUT_LAST_ACK=7,
 288         NET_NF_CONNTRACK_TCP_TIMEOUT_TIME_WAIT=8,
 289         NET_NF_CONNTRACK_TCP_TIMEOUT_CLOSE=9,
 290         NET_NF_CONNTRACK_UDP_TIMEOUT=10,
 291         NET_NF_CONNTRACK_UDP_TIMEOUT_STREAM=11,
 292         NET_NF_CONNTRACK_ICMP_TIMEOUT=12,
 293         NET_NF_CONNTRACK_GENERIC_TIMEOUT=13,
 294         NET_NF_CONNTRACK_BUCKETS=14,
 295         NET_NF_CONNTRACK_LOG_INVALID=15,
 296         NET_NF_CONNTRACK_TCP_TIMEOUT_MAX_RETRANS=16,
 297         NET_NF_CONNTRACK_TCP_LOOSE=17,
 298         NET_NF_CONNTRACK_TCP_BE_LIBERAL=18,
 299         NET_NF_CONNTRACK_TCP_MAX_RETRANS=19,
 300         NET_NF_CONNTRACK_SCTP_TIMEOUT_CLOSED=20,
 301         NET_NF_CONNTRACK_SCTP_TIMEOUT_COOKIE_WAIT=21,
 302         NET_NF_CONNTRACK_SCTP_TIMEOUT_COOKIE_ECHOED=22,
 303         NET_NF_CONNTRACK_SCTP_TIMEOUT_ESTABLISHED=23,
 304         NET_NF_CONNTRACK_SCTP_TIMEOUT_SHUTDOWN_SENT=24,
 305         NET_NF_CONNTRACK_SCTP_TIMEOUT_SHUTDOWN_RECD=25,
 306         NET_NF_CONNTRACK_SCTP_TIMEOUT_SHUTDOWN_ACK_SENT=26,
 307         NET_NF_CONNTRACK_COUNT=27,
 308         NET_NF_CONNTRACK_ICMPV6_TIMEOUT=28,
 309         NET_NF_CONNTRACK_FRAG6_TIMEOUT=29,
 310         NET_NF_CONNTRACK_FRAG6_LOW_THRESH=30,
 311         NET_NF_CONNTRACK_FRAG6_HIGH_THRESH=31,
 312 };
 313
 314 /* /proc/sys/net/ipv4 */
 315 enum
 316 {
 317         /* v2.0 compatibile variables */
 318         NET_IPV4_FORWARD=8,
 319         NET_IPV4_DYNADDR=9,
 320
 321         NET_IPV4_CONF=16,
 322         NET_IPV4_NEIGH=17,
 323         NET_IPV4_ROUTE=18,
 324         NET_IPV4_FIB_HASH=19,
 325         NET_IPV4_NETFILTER=20,
 326
 327         NET_IPV4_TCP_TIMESTAMPS=33,
 328         NET_IPV4_TCP_WINDOW_SCALING=34,
 329         NET_IPV4_TCP_SACK=35,
 330         NET_IPV4_TCP_RETRANS_COLLAPSE=36,
 331         NET_IPV4_DEFAULT_TTL=37,
 332         NET_IPV4_AUTOCONFIG=38,
 333         NET_IPV4_NO_PMTU_DISC=39,
 334         NET_IPV4_TCP_SYN_RETRIES=40,
 335         NET_IPV4_IPFRAG_HIGH_THRESH=41,
 336         NET_IPV4_IPFRAG_LOW_THRESH=42,
 337         NET_IPV4_IPFRAG_TIME=43,
 338         NET_IPV4_TCP_MAX_KA_PROBES=44,
 339         NET_IPV4_TCP_KEEPALIVE_TIME=45,
 340         NET_IPV4_TCP_KEEPALIVE_PROBES=46,
 341         NET_IPV4_TCP_RETRIES1=47,
 342         NET_IPV4_TCP_RETRIES2=48,
 343         NET_IPV4_TCP_FIN_TIMEOUT=49,
 344         NET_IPV4_IP_MASQ_DEBUG=50,
 345         NET_TCP_SYNCOOKIES=51,
 346         NET_TCP_STDURG=52,
 347         NET_TCP_RFC1337=53,
 348         NET_TCP_SYN_TAILDROP=54,
 349         NET_TCP_MAX_SYN_BACKLOG=55,
 350         NET_IPV4_LOCAL_PORT_RANGE=56,
 351         NET_IPV4_ICMP_ECHO_IGNORE_ALL=57,
 352         NET_IPV4_ICMP_ECHO_IGNORE_BROADCASTS=58,
 353         NET_IPV4_ICMP_SOURCEQUENCH_RATE=59,
 354         NET_IPV4_ICMP_DESTUNREACH_RATE=60,
 355         NET_IPV4_ICMP_TIMEEXCEED_RATE=61,
 356         NET_IPV4_ICMP_PARAMPROB_RATE=62,
 357         NET_IPV4_ICMP_ECHOREPLY_RATE=63,
 358         NET_IPV4_ICMP_IGNORE_BOGUS_ERROR_RESPONSES=64,
 359         NET_IPV4_IGMP_MAX_MEMBERSHIPS=65,
 360         NET_TCP_TW_RECYCLE=66,
 361         NET_IPV4_ALWAYS_DEFRAG=67,
 362         NET_IPV4_TCP_KEEPALIVE_INTVL=68,
 363         NET_IPV4_INET_PEER_THRESHOLD=69,
 364         NET_IPV4_INET_PEER_MINTTL=70,
 365         NET_IPV4_INET_PEER_MAXTTL=71,
 366         NET_IPV4_INET_PEER_GC_MINTIME=72,
 367         NET_IPV4_INET_PEER_GC_MAXTIME=73,
 368         NET_TCP_ORPHAN_RETRIES=74,
 369         NET_TCP_ABORT_ON_OVERFLOW=75,
 370         NET_TCP_SYNACK_RETRIES=76,
 371         NET_TCP_MAX_ORPHANS=77,
 372         NET_TCP_MAX_TW_BUCKETS=78,
 373         NET_TCP_FACK=79,
 374         NET_TCP_REORDERING=80,
 375         NET_TCP_ECN=81,
 376         NET_TCP_DSACK=82,
 377         NET_TCP_MEM=83,
 378         NET_TCP_WMEM=84,
 379         NET_TCP_RMEM=85,
 380         NET_TCP_APP_WIN=86,
 381         NET_TCP_ADV_WIN_SCALE=87,
 382         NET_IPV4_NONLOCAL_BIND=88,
 383         NET_IPV4_ICMP_RATELIMIT=89,
 384         NET_IPV4_ICMP_RATEMASK=90,
 385         NET_TCP_TW_REUSE=91,
 386         NET_TCP_FRTO=92,
 387         NET_TCP_LOW_LATENCY=93,
 388         NET_IPV4_IPFRAG_SECRET_INTERVAL=94,
 389         NET_IPV4_IGMP_MAX_MSF=96,
 390         NET_TCP_NO_METRICS_SAVE=97,
 391         NET_TCP_DEFAULT_WIN_SCALE=105,
 392         NET_TCP_MODERATE_RCVBUF=106,
 393         NET_TCP_TSO_WIN_DIVISOR=107,
 394         NET_TCP_BIC_BETA=108,
 395         NET_IPV4_ICMP_ERRORS_USE_INBOUND_IFADDR=109,
 396         NET_TCP_CONG_CONTROL=110,
 397         NET_TCP_ABC=111,
 398         NET_IPV4_IPFRAG_MAX_DIST=112,
 399 };
 400
 401 enum {
 402         NET_IPV4_ROUTE_FLUSH=1,
 403         NET_IPV4_ROUTE_MIN_DELAY=2,
 404         NET_IPV4_ROUTE_MAX_DELAY=3,
 405         NET_IPV4_ROUTE_GC_THRESH=4,
 406         NET_IPV4_ROUTE_MAX_SIZE=5,
 407         NET_IPV4_ROUTE_GC_MIN_INTERVAL=6,
 408         NET_IPV4_ROUTE_GC_TIMEOUT=7,
 409         NET_IPV4_ROUTE_GC_INTERVAL=8,
 410         NET_IPV4_ROUTE_REDIRECT_LOAD=9,
 411         NET_IPV4_ROUTE_REDIRECT_NUMBER=10,
 412         NET_IPV4_ROUTE_REDIRECT_SILENCE=11,
 413         NET_IPV4_ROUTE_ERROR_COST=12,
 414         NET_IPV4_ROUTE_ERROR_BURST=13,
 415         NET_IPV4_ROUTE_GC_ELASTICITY=14,
 416         NET_IPV4_ROUTE_MTU_EXPIRES=15,
 417         NET_IPV4_ROUTE_MIN_PMTU=16,
 418         NET_IPV4_ROUTE_MIN_ADVMSS=17,
 419         NET_IPV4_ROUTE_SECRET_INTERVAL=18,
 420         NET_IPV4_ROUTE_GC_MIN_INTERVAL_MS=19,
 421 };
 422
 423 enum
 424 {
 425         NET_PROTO_CONF_ALL=-2,
 426         NET_PROTO_CONF_DEFAULT=-3
 427
 428         /* And device ifindices ... */
 429 };
 430
 431 enum
 432 {
 433         NET_IPV4_CONF_FORWARDING=1,
 434         NET_IPV4_CONF_MC_FORWARDING=2,
 435         NET_IPV4_CONF_PROXY_ARP=3,
 436         NET_IPV4_CONF_ACCEPT_REDIRECTS=4,
 437         NET_IPV4_CONF_SECURE_REDIRECTS=5,
 438         NET_IPV4_CONF_SEND_REDIRECTS=6,
 439         NET_IPV4_CONF_SHARED_MEDIA=7,
 440         NET_IPV4_CONF_RP_FILTER=8,
 441         NET_IPV4_CONF_ACCEPT_SOURCE_ROUTE=9,
 442         NET_IPV4_CONF_BOOTP_RELAY=10,
 443         NET_IPV4_CONF_LOG_MARTIANS=11,
 444         NET_IPV4_CONF_TAG=12,
 445         NET_IPV4_CONF_ARPFILTER=13,
 446         NET_IPV4_CONF_MEDIUM_ID=14,
 447         NET_IPV4_CONF_NOXFRM=15,
 448         NET_IPV4_CONF_NOPOLICY=16,
 449         NET_IPV4_CONF_FORCE_IGMP_VERSION=17,
 450         NET_IPV4_CONF_ARP_ANNOUNCE=18,
 451         NET_IPV4_CONF_ARP_IGNORE=19,
 452         NET_IPV4_CONF_PROMOTE_SECONDARIES=20,
 453         __NET_IPV4_CONF_MAX
 454 };
 455
 456 /* /proc/sys/net/ipv4/netfilter */
 457 enum
 458 {
 459         NET_IPV4_NF_CONNTRACK_MAX=1,
 460         NET_IPV4_NF_CONNTRACK_TCP_TIMEOUT_SYN_SENT=2,
 461         NET_IPV4_NF_CONNTRACK_TCP_TIMEOUT_SYN_RECV=3,
 462         NET_IPV4_NF_CONNTRACK_TCP_TIMEOUT_ESTABLISHED=4,
 463         NET_IPV4_NF_CONNTRACK_TCP_TIMEOUT_FIN_WAIT=5,
 464         NET_IPV4_NF_CONNTRACK_TCP_TIMEOUT_CLOSE_WAIT=6,
 465         NET_IPV4_NF_CONNTRACK_TCP_TIMEOUT_LAST_ACK=7,
 466         NET_IPV4_NF_CONNTRACK_TCP_TIMEOUT_TIME_WAIT=8,
 467         NET_IPV4_NF_CONNTRACK_TCP_TIMEOUT_CLOSE=9,
 468         NET_IPV4_NF_CONNTRACK_UDP_TIMEOUT=10,
 469         NET_IPV4_NF_CONNTRACK_UDP_TIMEOUT_STREAM=11,
 470         NET_IPV4_NF_CONNTRACK_ICMP_TIMEOUT=12,
 471         NET_IPV4_NF_CONNTRACK_GENERIC_TIMEOUT=13,
 472         NET_IPV4_NF_CONNTRACK_BUCKETS=14,
 473         NET_IPV4_NF_CONNTRACK_LOG_INVALID=15,
 474         NET_IPV4_NF_CONNTRACK_TCP_TIMEOUT_MAX_RETRANS=16,
 475         NET_IPV4_NF_CONNTRACK_TCP_LOOSE=17,
 476         NET_IPV4_NF_CONNTRACK_TCP_BE_LIBERAL=18,
 477         NET_IPV4_NF_CONNTRACK_TCP_MAX_RETRANS=19,
 478         NET_IPV4_NF_CONNTRACK_SCTP_TIMEOUT_CLOSED=20,
 479         NET_IPV4_NF_CONNTRACK_SCTP_TIMEOUT_COOKIE_WAIT=21,
 480         NET_IPV4_NF_CONNTRACK_SCTP_TIMEOUT_COOKIE_ECHOED=22,
 481         NET_IPV4_NF_CONNTRACK_SCTP_TIMEOUT_ESTABLISHED=23,
 482         NET_IPV4_NF_CONNTRACK_SCTP_TIMEOUT_SHUTDOWN_SENT=24,
 483         NET_IPV4_NF_CONNTRACK_SCTP_TIMEOUT_SHUTDOWN_RECD=25,
 484         NET_IPV4_NF_CONNTRACK_SCTP_TIMEOUT_SHUTDOWN_ACK_SENT=26,
 485         NET_IPV4_NF_CONNTRACK_COUNT=27,
 486 };
 487
 488 /* /proc/sys/net/ipv6 */
 489 enum {
 490         NET_IPV6_CONF=16,
 491         NET_IPV6_NEIGH=17,
 492         NET_IPV6_ROUTE=18,
 493         NET_IPV6_ICMP=19,
 494         NET_IPV6_BINDV6ONLY=20,
 495         NET_IPV6_IP6FRAG_HIGH_THRESH=21,
 496         NET_IPV6_IP6FRAG_LOW_THRESH=22,
 497         NET_IPV6_IP6FRAG_TIME=23,
 498         NET_IPV6_IP6FRAG_SECRET_INTERVAL=24,
 499         NET_IPV6_MLD_MAX_MSF=25,
 500 };
 501
 502 enum {
 503         NET_IPV6_ROUTE_FLUSH=1,
 504         NET_IPV6_ROUTE_GC_THRESH=2,
 505         NET_IPV6_ROUTE_MAX_SIZE=3,
 506         NET_IPV6_ROUTE_GC_MIN_INTERVAL=4,
 507         NET_IPV6_ROUTE_GC_TIMEOUT=5,
 508         NET_IPV6_ROUTE_GC_INTERVAL=6,
 509         NET_IPV6_ROUTE_GC_ELASTICITY=7,
 510         NET_IPV6_ROUTE_MTU_EXPIRES=8,
 511         NET_IPV6_ROUTE_MIN_ADVMSS=9,
 512         NET_IPV6_ROUTE_GC_MIN_INTERVAL_MS=10
 513 };
 514
 515 enum {
 516         NET_IPV6_FORWARDING=1,
 517         NET_IPV6_HOP_LIMIT=2,
 518         NET_IPV6_MTU=3,
 519         NET_IPV6_ACCEPT_RA=4,
 520         NET_IPV6_ACCEPT_REDIRECTS=5,
 521         NET_IPV6_AUTOCONF=6,
 522         NET_IPV6_DAD_TRANSMITS=7,
 523         NET_IPV6_RTR_SOLICITS=8,
 524         NET_IPV6_RTR_SOLICIT_INTERVAL=9,
 525         NET_IPV6_RTR_SOLICIT_DELAY=10,
 526         NET_IPV6_USE_TEMPADDR=11,
 527         NET_IPV6_TEMP_VALID_LFT=12,
 528         NET_IPV6_TEMP_PREFERED_LFT=13,
 529         NET_IPV6_REGEN_MAX_RETRY=14,
 530         NET_IPV6_MAX_DESYNC_FACTOR=15,
 531         NET_IPV6_MAX_ADDRESSES=16,
 532         NET_IPV6_FORCE_MLD_VERSION=17,
 533         __NET_IPV6_MAX
 534 };
 535
 536 /* /proc/sys/net/ipv6/icmp */
 537 enum {
 538         NET_IPV6_ICMP_RATELIMIT=1
 539 };
 540
 541 /* /proc/sys/net/<protocol>/neigh/<dev> */
 542 enum {
 543         NET_NEIGH_MCAST_SOLICIT=1,
 544         NET_NEIGH_UCAST_SOLICIT=2,
 545         NET_NEIGH_APP_SOLICIT=3,
 546         NET_NEIGH_RETRANS_TIME=4,
 547         NET_NEIGH_REACHABLE_TIME=5,
 548         NET_NEIGH_DELAY_PROBE_TIME=6,
 549         NET_NEIGH_GC_STALE_TIME=7,
 550         NET_NEIGH_UNRES_QLEN=8,
 551         NET_NEIGH_PROXY_QLEN=9,
 552         NET_NEIGH_ANYCAST_DELAY=10,
 553         NET_NEIGH_PROXY_DELAY=11,
 554         NET_NEIGH_LOCKTIME=12,
 555         NET_NEIGH_GC_INTERVAL=13,
 556         NET_NEIGH_GC_THRESH1=14,
 557         NET_NEIGH_GC_THRESH2=15,
 558         NET_NEIGH_GC_THRESH3=16,
 559         NET_NEIGH_RETRANS_TIME_MS=17,
 560         NET_NEIGH_REACHABLE_TIME_MS=18,
 561         __NET_NEIGH_MAX
 562 };
 563
 564 /* /proc/sys/net/ipx */
 565 enum {
 566         NET_IPX_PPROP_BROADCASTING=1,
 567         NET_IPX_FORWARDING=2
 568 };
 569
 570 /* /proc/sys/net/llc */
 571 enum {
 572         NET_LLC2=1,
 573         NET_LLC_STATION=2,
 574 };
 575
 576 /* /proc/sys/net/llc/llc2 */
 577 enum {
 578         NET_LLC2_TIMEOUT=1,
 579 };
 580
 581 /* /proc/sys/net/llc/station */
 582 enum {
 583         NET_LLC_STATION_ACK_TIMEOUT=1,
 584 };
 585
 586 /* /proc/sys/net/llc/llc2/timeout */
 587 enum {
 588         NET_LLC2_ACK_TIMEOUT=1,
 589         NET_LLC2_P_TIMEOUT=2,
 590         NET_LLC2_REJ_TIMEOUT=3,
 591         NET_LLC2_BUSY_TIMEOUT=4,
 592 };
 593
 594 /* /proc/sys/net/appletalk */
 595 enum {
 596         NET_ATALK_AARP_EXPIRY_TIME=1,
 597         NET_ATALK_AARP_TICK_TIME=2,
 598         NET_ATALK_AARP_RETRANSMIT_LIMIT=3,
 599         NET_ATALK_AARP_RESOLVE_TIME=4
 600 };
 601
 602
 603 /* /proc/sys/net/netrom */
 604 enum {
 605         NET_NETROM_DEFAULT_PATH_QUALITY=1,
 606         NET_NETROM_OBSOLESCENCE_COUNT_INITIALISER=2,
 607         NET_NETROM_NETWORK_TTL_INITIALISER=3,
 608         NET_NETROM_TRANSPORT_TIMEOUT=4,
 609         NET_NETROM_TRANSPORT_MAXIMUM_TRIES=5,
 610         NET_NETROM_TRANSPORT_ACKNOWLEDGE_DELAY=6,
 611         NET_NETROM_TRANSPORT_BUSY_DELAY=7,
 612         NET_NETROM_TRANSPORT_REQUESTED_WINDOW_SIZE=8,
 613         NET_NETROM_TRANSPORT_NO_ACTIVITY_TIMEOUT=9,
 614         NET_NETROM_ROUTING_CONTROL=10,
 615         NET_NETROM_LINK_FAILS_COUNT=11,
 616         NET_NETROM_RESET=12
 617 };
 618
 619 /* /proc/sys/net/ax25 */
 620 enum {
 621         NET_AX25_IP_DEFAULT_MODE=1,
 622         NET_AX25_DEFAULT_MODE=2,
 623         NET_AX25_BACKOFF_TYPE=3,
 624         NET_AX25_CONNECT_MODE=4,
 625         NET_AX25_STANDARD_WINDOW=5,
 626         NET_AX25_EXTENDED_WINDOW=6,
 627         NET_AX25_T1_TIMEOUT=7,
 628         NET_AX25_T2_TIMEOUT=8,
 629         NET_AX25_T3_TIMEOUT=9,
 630         NET_AX25_IDLE_TIMEOUT=10,
 631         NET_AX25_N2=11,
 632         NET_AX25_PACLEN=12,
 633         NET_AX25_PROTOCOL=13,
 634         NET_AX25_DAMA_SLAVE_TIMEOUT=14
 635 };
 636
 637 /* /proc/sys/net/rose */
 638 enum {
 639         NET_ROSE_RESTART_REQUEST_TIMEOUT=1,
 640         NET_ROSE_CALL_REQUEST_TIMEOUT=2,
 641         NET_ROSE_RESET_REQUEST_TIMEOUT=3,
 642         NET_ROSE_CLEAR_REQUEST_TIMEOUT=4,
 643         NET_ROSE_ACK_HOLD_BACK_TIMEOUT=5,
 644         NET_ROSE_ROUTING_CONTROL=6,
 645         NET_ROSE_LINK_FAIL_TIMEOUT=7,
 646         NET_ROSE_MAX_VCS=8,
 647         NET_ROSE_WINDOW_SIZE=9,
 648         NET_ROSE_NO_ACTIVITY_TIMEOUT=10
 649 };
 650
 651 /* /proc/sys/net/x25 */
 652 enum {
 653         NET_X25_RESTART_REQUEST_TIMEOUT=1,
 654         NET_X25_CALL_REQUEST_TIMEOUT=2,
 655         NET_X25_RESET_REQUEST_TIMEOUT=3,
 656         NET_X25_CLEAR_REQUEST_TIMEOUT=4,
 657         NET_X25_ACK_HOLD_BACK_TIMEOUT=5
 658 };
 659
 660 /* /proc/sys/net/token-ring */
 661 enum
 662 {
 663         NET_TR_RIF_TIMEOUT=1
 664 };
 665
 666 /* /proc/sys/net/decnet/ */
 667 enum {
 668         NET_DECNET_NODE_TYPE = 1,
 669         NET_DECNET_NODE_ADDRESS = 2,
 670         NET_DECNET_NODE_NAME = 3,
 671         NET_DECNET_DEFAULT_DEVICE = 4,
 672         NET_DECNET_TIME_WAIT = 5,
 673         NET_DECNET_DN_COUNT = 6,
 674         NET_DECNET_DI_COUNT = 7,
 675         NET_DECNET_DR_COUNT = 8,
 676         NET_DECNET_DST_GC_INTERVAL = 9,
 677         NET_DECNET_CONF = 10,
 678         NET_DECNET_NO_FC_MAX_CWND = 11,
 679         NET_DECNET_MEM = 12,
 680         NET_DECNET_RMEM = 13,
 681         NET_DECNET_WMEM = 14,
 682         NET_DECNET_DEBUG_LEVEL = 255
 683 };
 684
 685 /* /proc/sys/net/decnet/conf/<dev> */
 686 enum {
 687         NET_DECNET_CONF_LOOPBACK = -2,
 688         NET_DECNET_CONF_DDCMP = -3,
 689         NET_DECNET_CONF_PPP = -4,
 690         NET_DECNET_CONF_X25 = -5,
 691         NET_DECNET_CONF_GRE = -6,
 692         NET_DECNET_CONF_ETHER = -7
 693
 694         /* ... and ifindex of devices */
 695 };
 696
 697 /* /proc/sys/net/decnet/conf/<dev>/ */
 698 enum {
 699         NET_DECNET_CONF_DEV_PRIORITY = 1,
 700         NET_DECNET_CONF_DEV_T1 = 2,
 701         NET_DECNET_CONF_DEV_T2 = 3,
 702         NET_DECNET_CONF_DEV_T3 = 4,
 703         NET_DECNET_CONF_DEV_FORWARDING = 5,
 704         NET_DECNET_CONF_DEV_BLKSIZE = 6,
 705         NET_DECNET_CONF_DEV_STATE = 7
 706 };
 707
 708 /* /proc/sys/net/sctp */
 709 enum {
 710         NET_SCTP_RTO_INITIAL = 1,
 711         NET_SCTP_RTO_MIN     = 2,
 712         NET_SCTP_RTO_MAX     = 3,
 713         NET_SCTP_RTO_ALPHA   = 4,
 714         NET_SCTP_RTO_BETA    = 5,
 715         NET_SCTP_VALID_COOKIE_LIFE       =  6,
 716         NET_SCTP_ASSOCIATION_MAX_RETRANS =  7,
 717         NET_SCTP_PATH_MAX_RETRANS        =  8,
 718         NET_SCTP_MAX_INIT_RETRANSMITS    =  9,
 719         NET_SCTP_HB_INTERVAL             = 10,
 720         NET_SCTP_PRESERVE_ENABLE         = 11,
 721         NET_SCTP_MAX_BURST               = 12,
 722         NET_SCTP_ADDIP_ENABLE            = 13,
 723         NET_SCTP_PRSCTP_ENABLE           = 14,
 724         NET_SCTP_SNDBUF_POLICY           = 15,
 725         NET_SCTP_SACK_TIMEOUT            = 16,
 726         NET_SCTP_RCVBUF_POLICY           = 17,
 727 };
 728
 729 /* /proc/sys/net/bridge */
 730 enum {
 731         NET_BRIDGE_NF_CALL_ARPTABLES = 1,
 732         NET_BRIDGE_NF_CALL_IPTABLES = 2,
 733         NET_BRIDGE_NF_CALL_IP6TABLES = 3,
 734         NET_BRIDGE_NF_FILTER_VLAN_TAGGED = 4,
 735 };
 736
 737 /* CTL_PROC names: */
 738
 739 /* CTL_FS names: */
 740 enum
 741 {
 742         FS_NRINODE=1,   /* int:current number of allocated inodes */
 743         FS_STATINODE=2,
 744         FS_MAXINODE=3,  /* int:maximum number of inodes that can be allocated */
 745         FS_NRDQUOT=4,   /* int:current number of allocated dquots */
 746         FS_MAXDQUOT=5,  /* int:maximum number of dquots that can be allocated */
 747         FS_NRFILE=6,    /* int:current number of allocated filedescriptors */
 748         FS_MAXFILE=7,   /* int:maximum number of filedescriptors that can be allocated */
 749         FS_DENTRY=8,
 750         FS_NRSUPER=9,   /* int:current number of allocated super_blocks */
 751         FS_MAXSUPER=10, /* int:maximum number of super_blocks that can be allocated */
 752         FS_OVERFLOWUID=11,      /* int: overflow UID */
 753         FS_OVERFLOWGID=12,      /* int: overflow GID */
 754         FS_LEASES=13,   /* int: leases enabled */
 755         FS_DIR_NOTIFY=14,       /* int: directory notification enabled */
 756         FS_LEASE_TIME=15,       /* int: maximum time to wait for a lease break */
 757         FS_DQSTATS=16,  /* disc quota usage statistics and control */
 758         FS_XFS=17,      /* struct: control xfs parameters */
 759         FS_AIO_NR=18,   /* current system-wide number of aio requests */
 760         FS_AIO_MAX_NR=19,       /* system-wide maximum number of aio requests */
 761         FS_INOTIFY=20,  /* inotify submenu */
 762 };
 763
 764 /* /proc/sys/fs/quota/ */
 765 enum {
 766         FS_DQ_LOOKUPS = 1,
 767         FS_DQ_DROPS = 2,
 768         FS_DQ_READS = 3,
 769         FS_DQ_WRITES = 4,
 770         FS_DQ_CACHE_HITS = 5,
 771         FS_DQ_ALLOCATED = 6,
 772         FS_DQ_FREE = 7,
 773         FS_DQ_SYNCS = 8,
 774         FS_DQ_WARNINGS = 9,
 775 };
 776
 777 /* CTL_DEBUG names: */
 778
 779 /* CTL_DEV names: */
 780 enum {
 781         DEV_CDROM=1,
 782         DEV_HWMON=2,
 783         DEV_PARPORT=3,
 784         DEV_RAID=4,
 785         DEV_MAC_HID=5,
 786         DEV_SCSI=6,
 787         DEV_IPMI=7,
 788 };
 789
 790 /* /proc/sys/dev/cdrom */
 791 enum {
 792         DEV_CDROM_INFO=1,
 793         DEV_CDROM_AUTOCLOSE=2,
 794         DEV_CDROM_AUTOEJECT=3,
 795         DEV_CDROM_DEBUG=4,
 796         DEV_CDROM_LOCK=5,
 797         DEV_CDROM_CHECK_MEDIA=6
 798 };
 799
 800 /* /proc/sys/dev/parport */
 801 enum {
 802         DEV_PARPORT_DEFAULT=-3
 803 };
 804
 805 /* /proc/sys/dev/raid */
 806 enum {
 807         DEV_RAID_SPEED_LIMIT_MIN=1,
 808         DEV_RAID_SPEED_LIMIT_MAX=2
 809 };
 810
 811 /* /proc/sys/dev/parport/default */
 812 enum {
 813         DEV_PARPORT_DEFAULT_TIMESLICE=1,
 814         DEV_PARPORT_DEFAULT_SPINTIME=2
 815 };
 816
 817 /* /proc/sys/dev/parport/parport n */
 818 enum {
 819         DEV_PARPORT_SPINTIME=1,
 820         DEV_PARPORT_BASE_ADDR=2,
 821         DEV_PARPORT_IRQ=3,
 822         DEV_PARPORT_DMA=4,
 823         DEV_PARPORT_MODES=5,
 824         DEV_PARPORT_DEVICES=6,
 825         DEV_PARPORT_AUTOPROBE=16
 826 };
 827
 828 /* /proc/sys/dev/parport/parport n/devices/ */
 829 enum {
 830         DEV_PARPORT_DEVICES_ACTIVE=-3,
 831 };
 832
 833 /* /proc/sys/dev/parport/parport n/devices/device n */
 834 enum {
 835         DEV_PARPORT_DEVICE_TIMESLICE=1,
 836 };
 837
 838 /* /proc/sys/dev/mac_hid */
 839 enum {
 840         DEV_MAC_HID_KEYBOARD_SENDS_LINUX_KEYCODES=1,
 841         DEV_MAC_HID_KEYBOARD_LOCK_KEYCODES=2,
 842         DEV_MAC_HID_MOUSE_BUTTON_EMULATION=3,
 843         DEV_MAC_HID_MOUSE_BUTTON2_KEYCODE=4,
 844         DEV_MAC_HID_MOUSE_BUTTON3_KEYCODE=5,
 845         DEV_MAC_HID_ADB_MOUSE_SENDS_KEYCODES=6
 846 };
 847
 848 /* /proc/sys/dev/scsi */
 849 enum {
 850         DEV_SCSI_LOGGING_LEVEL=1,
 851 };
 852
 853 /* /proc/sys/dev/ipmi */
 854 enum {
 855         DEV_IPMI_POWEROFF_POWERCYCLE=1,
 856 };
 857
 858 /* /proc/sys/abi */
 859 enum
 860 {
 861         ABI_DEFHANDLER_COFF=1,  /* default handler for coff binaries */
 862         ABI_DEFHANDLER_ELF=2,   /* default handler for ELF binaries */
 863         ABI_DEFHANDLER_LCALL7=3,/* default handler for procs using lcall7 */
 864         ABI_DEFHANDLER_LIBCSO=4,/* default handler for an libc.so ELF interp */
 865         ABI_TRACE=5,            /* tracing flags */
 866         ABI_FAKE_UTSNAME=6,     /* fake target utsname information */
 867 };
 868
 869 #ifdef __KERNEL__
 870 #include <linux/list.h>
 871
 872 extern void sysctl_init(void);
 873
 874 typedef struct ctl_table ctl_table;
 875
 876 typedef int ctl_handler (ctl_table *table, int __user *name, int nlen,
 877                          void __user *oldval, size_t __user *oldlenp,
 878                          void __user *newval, size_t newlen,
 879                          void **context);
 880
 881 typedef int proc_handler (ctl_table *ctl, int write, struct file * filp,
 882                           void __user *buffer, size_t *lenp, loff_t *ppos);
 883
 884 extern int proc_dostring(ctl_table *, int, struct file *,
 885                          void __user *, size_t *, loff_t *);
 886 extern int proc_dointvec(ctl_table *, int, struct file *,
 887                          void __user *, size_t *, loff_t *);
 888 extern int proc_dointvec_bset(ctl_table *, int, struct file *,
 889                               void __user *, size_t *, loff_t *);
 890 extern int proc_dointvec_minmax(ctl_table *, int, struct file *,
 891                                 void __user *, size_t *, loff_t *);
 892 extern int proc_dointvec_jiffies(ctl_table *, int, struct file *,
 893                                  void __user *, size_t *, loff_t *);
 894 extern int proc_dointvec_userhz_jiffies(ctl_table *, int, struct file *,
 895                                         void __user *, size_t *, loff_t *);
 896 extern int proc_dointvec_ms_jiffies(ctl_table *, int, struct file *,
 897                                     void __user *, size_t *, loff_t *);
 898 extern int proc_doulongvec_minmax(ctl_table *, int, struct file *,
 899                                   void __user *, size_t *, loff_t *);
 900 extern int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int,
 901                                       struct file *, void __user *, size_t *, loff_t *);
 902
 903 extern int do_sysctl (int __user *name, int nlen,
 904                       void __user *oldval, size_t __user *oldlenp,
 905                       void __user *newval, size_t newlen);
 906
 907 extern int do_sysctl_strategy (ctl_table *table,
 908                                int __user *name, int nlen,
 909                                void __user *oldval, size_t __user *oldlenp,
 910                                void __user *newval, size_t newlen, void ** context);
 911
 912 extern ctl_handler sysctl_string;
 913 extern ctl_handler sysctl_intvec;
 914 extern ctl_handler sysctl_jiffies;
 915 extern ctl_handler sysctl_ms_jiffies;
 916
 917
 918 /*
 919  * Register a set of sysctl names by calling register_sysctl_table
 920  * with an initialised array of ctl_table's.  An entry with zero
 921  * ctl_name terminates the table.  table->de will be set up by the
 922  * registration and need not be initialised in advance.
 923  *
 924  * sysctl names can be mirrored automatically under /proc/sys.  The
 925  * procname supplied controls /proc naming.
 926  *
 927  * The table's mode will be honoured both for sys_sysctl(2) and
 928  * proc-fs access.
 929  *
 930  * Leaf nodes in the sysctl tree will be represented by a single file
 931  * under /proc; non-leaf nodes will be represented by directories.  A
 932  * null procname disables /proc mirroring at this node.
 933  *
 934  * sysctl(2) can automatically manage read and write requests through
 935  * the sysctl table.  The data and maxlen fields of the ctl_table
 936  * struct enable minimal validation of the values being written to be
 937  * performed, and the mode field allows minimal authentication.
 938  *
 939  * More sophisticated management can be enabled by the provision of a
 940  * strategy routine with the table entry.  This will be called before
 941  * any automatic read or write of the data is performed.
 942  *
 943  * The strategy routine may return:
 944  * <0: Error occurred (error is passed to user process)
 945  * 0:  OK - proceed with automatic read or write.
 946  * >0: OK - read or write has been done by the strategy routine, so
 947  *     return immediately.
 948  *
 949  * There must be a proc_handler routine for any terminal nodes
 950  * mirrored under /proc/sys (non-terminals are handled by a built-in
 951  * directory handler).  Several default handlers are available to
 952  * cover common cases.
 953  */
 954
 955 /* A sysctl table is an array of struct ctl_table: */
 956 struct ctl_table
 957 {
 958         int ctl_name;                   /* Binary ID */
 959         const char *procname;           /* Text ID for /proc/sys, or zero */
 960         void *data;
 961         int maxlen;
 962         mode_t mode;
 963         ctl_table *child;
 964         proc_handler *proc_handler;     /* Callback for text formatting */
 965         ctl_handler *strategy;          /* Callback function for all r/w */
 966         struct proc_dir_entry *de;      /* /proc control block */
 967         void *extra1;
 968         void *extra2;
 969 };
 970
 971 /* struct ctl_table_header is used to maintain dynamic lists of
 972    ctl_table trees. */
 973 struct ctl_table_header
 974 {
 975         ctl_table *ctl_table;
 976         struct list_head ctl_entry;
 977         int used;
 978         struct completion *unregistering;
 979 };
 980
 981 struct ctl_table_header * register_sysctl_table(ctl_table * table,
 982                                                 int insert_at_head);
 983 void unregister_sysctl_table(struct ctl_table_header * table);
 984
 985 #else /* __KERNEL__ */
 986
 987 #endif /* __KERNEL__ */
 988
 989 #endif /* _LINUX_SYSCTL_H */