An argument type of 'const struct foo *' means the argument is input
to the kernel.  'struct foo *' means the kernel outputs the argument.
If the kernel uses the argument for both input and output, this is
marked with // I-O.

Some ioctls take more arguments or return more values than a single
structure.  These are marked // MORE and documented further in a
separate section.

This list is incomplete.  It does not include:

    -- Ioctls defined internal to the kernel ('scsi_ioctl.h').
    -- Ioctls defined in modules distributed separately from the kernel.

And, of course, I may have errors and omissions.

Please e-mail changes and comments to <>.  I am
particularly interested in loadable modules which define their own
ioctls.  If you know of such a module, tell me where I can ftp it, and
I'll include its ioctls in my next release.

// Main table.

// <include/asm-i386/socket.h>
0x00008901  FIOSETOWN                   const int *
0x00008902  SIOCSPGRP                   const int *
0x00008903  FIOGETOWN                   int *
0x00008904  SIOCGPGRP                   int *
0x00008905  SIOCATMARK                  int *
0x00008906  SIOCGSTAMP                  timeval *

// <include/asm-i386/termios.h>
0x00005401  TCGETS                      struct termios *
0x00005402  TCSETS                      const struct termios *
0x00005403  TCSETSW                     const struct termios *
0x00005404  TCSETSF                     const struct termios *
0x00005405  TCGETA                      struct termio *
0x00005406  TCSETA                      const struct termio *
0x00005407  TCSETAW                     const struct termio *
0x00005408  TCSETAF                     const struct termio *
0x00005409  TCSBRK                      int
0x0000540A  TCXONC                      int
0x0000540B  TCFLSH                      int
0x0000540C  TIOCEXCL                    void
0x0000540D  TIOCNXCL                    void
0x0000540E  TIOCSCTTY                   int
0x0000540F  TIOCGPGRP                   pid_t *
0x00005410  TIOCSPGRP                   const pid_t *
0x00005411  TIOCOUTQ                    int *
0x0000541F  TIOCSSERIAL                 const struct serial_struct *
0x00005420  TIOCPKT                     const int *
0x00005421  FIONBIO                     const int *
0x00005422  TIOCNOTTY                   void
0x00005423  TIOCSETD                    const int *
0x00005424  TIOCGETD                    int *
0x00005425  TCSBRKP                     int
0x00005426  TIOCTTYGSTRUCT              struct tty_struct *
0x00005450  FIONCLEX                    void
0x00005451  FIOCLEX                     void
0x00005452  FIOASYNC                    const int *
0x00005453  TIOCSERCONFIG               void
0x00005454  TIOCSERGWILD                int *
0x00005455  TIOCSERSWILD                const int *
0x00005456  TIOCGLCKTRMIOS              struct termios *
0x00005457  TIOCSLCKTRMIOS              const struct temios *
0x00005458  TIOCSERGSTRUCT              struct async_struct *
0x00005459  TIOCSERGETLSR               int *
0x0000545A  TIOCSERGETMULTI             struct serial_multiport_struct *
0x0000545B  TIOCSERSETMULTI             const struct serial_multiport_struct *

// <include/linux/ax25.h>
0x000089E0  SIOCAX25GETUID              const struct sockaddr_ax25 *
0x000089E1  SIOCAX25ADDUID              const struct sockaddr_ax25 *
0x000089E2  SIOCAX25DELUID              const struct sockaddr_ax25 *
0x000089E3  SIOCAX25NOUID               const int *
0x000089E4  SIOCAX25DIGCTL              const int *
0x000089E5  SIOCAX25GETPARMS            struct ax25_parms_struct *      // I-O
0x000089E6  SIOCAX25SETPARMS            const struct ax25_parms-struct *

// <include/linux/cdk.h>
0x00007314  STL_BINTR                   void
0x00007315  STL_BSTART                  void
0x00007316  STL_BSTOP                   void
0x00007317  STL_BRESET                  void

// <include/linux/cdrom.h>
0x00005301  CDROMPAUSE                  void
0x00005302  CDROMRESUME                 void
0x00005303  CDROMPLAYMSF                const struct cdrom_msf *
0x00005304  CDROMPLAYTRKIND             const struct cdrom_ti *
0x00005305  CDROMREADTOCHDR             struct cdrom_tochdr *
0x00005306  CDROMREADTOCENTRY           struct cdrom_tocentry *         // I-O
0x00005307  CDROMSTOP                   void
0x00005308  CDROMSTART                  void
0x00005309  CDROMEJECT                  void
0x0000530A  CDROMVOLCTRL                const struct cdrom_volctrl *
0x0000530B  CDROMSUBCHNL                struct cdrom_subchnl *          // I-O
0x0000530C  CDROMREADMODE2              const struct cdrom_msf *        // MORE
0x0000530D  CDROMREADMODE1              const struct cdrom_msf *        // MORE
0x0000530E  CDROMREADAUDIO              const struct cdrom_read_audio * // MORE
0x0000530F  CDROMEJECT_SW               int
0x00435902  CYGETTHRESH                 int *
0x00435903  CYSETTHRESH                 int
0x00435904  CYGETDEFTHRESH              int *
0x00435905  CYSETDEFTHRESH              int
0x00435906  CYGETTIMEOUT                int *
0x00435907  CYSETTIMEOUT                int
0x00435908  CYGETDEFTIMEOUT             int *
0x00435909  CYSETDEFTIMEOUT             int

// <include/linux/ext2_fs.h>
0x80046601  EXT2_IOC_GETFLAGS           int *
0x40046602  EXT2_IOC_SETFLAGS           const int *
0x80047601  EXT2_IOC_GETVERSION         int *
0x40047602  EXT2_IOC_SETVERSION         const int *

// <include/linux/fd.h>
0x00000000  FDCLRPRM                    void
0x00000001  FDSETPRM                    const struct floppy_struct *
0x00000002  FDDEFPRM                    const struct floppy_struct *
0x00000003  FDGETPRM                    struct floppy_struct *
0x00000004  FDMSGON                     void
0x00000005  FDMSGOFF                    void
0x00000006  FDFMTBEG                    void
0x00000007  FDFMTTRK                    const struct format_descr *
0x00000008  FDFMTEND                    void
0x0000000A  FDSETEMSGTRESH              int
0x0000000B  FDFLUSH                     void
0x0000000C  FDSETMAXERRS                const struct floppy_max_errors *
0x0000000E  FDGETMAXERRS                struct floppy_max_errors *
0x00000010  FDGETDRVTYP                 struct { char [16]; } *
0x00000014  FDSETDRVPRM                 const struct floppy_drive_params *
0x00000015  FDGETDRVPRM                 struct floppy_drive_params *
0x00000016  FDGETDRVSTAT                struct floppy_drive_struct *
0x00000017  FDPOLLDRVSTAT               struct floppy_drive_struct *
0x00000018  FDRESET                     int
0x00000019  FDGETFDCSTAT                struct floppy_fdc_state *
0x0000001B  FDWERRORCLR                 void
0x0000001C  FDWERRORGET                 struct floppy_write_errors *
0x0000001E  FDRAWCMD                    struct floppy_raw_cmd * // MORE // I-O
0x00000028  FDTWADDLE                   void

// <include/linux/fs.h>
0x0000125D  BLKROSET                    const int *
0x0000125E  BLKROGET                    int *
0x0000125F  BLKRRPART                   void
0x00001260  BLKGETSIZE                  int *
0x00001261  BLKFLSBUF                   void
0x00001262  BLKRASET                    int
0x00001263  BLKRAGET                    int *
0x00000001  FIBMAP                      int *                           // I-O
0x00000002  FIGETBSZ                    int *

0x00000325  HDIO_SET_NOWERR             int
0x00000326  HDIO_SET_DMA                int

// <include/linux/if_eql.h>
0x000089F0  EQL_ENSLAVE                 struct ifreq *          // MORE // I-O
0x000089F1  EQL_EMANCIPATE              struct ifreq *          // MORE // I-O
0x000089F2  EQL_GETSLAVECFG             struct ifreq *          // MORE // I-O
0x000089F3  EQL_SETSLAVECFG             struct ifreq *          // MORE // I-O
0x000089F4  EQL_GETMASTRCFG             struct ifreq *          // MORE // I-O
0x000089F5  EQL_SETMASTRCFG             struct ifreq *          // MORE // I-O

// <include/linux/if_plip.h>
0x000089F0  SIOCDEVPLIP                 struct ifreq *                  // I-O

// <include/linux/if_ppp.h>
0x00005490  PPPIOCGFLAGS                int *
0x00005491  PPPIOCSFLAGS                const int *
0x00005492  PPPIOCGASYNCMAP             int *
0x00005493  PPPIOCSASYNCMAP             const int *
0x00005494  PPPIOCGUNIT                 int *
0x00005495  PPPIOCSINPSIG               const int *
0x00005497  PPPIOCSDEBUG                const int *
0x00005498  PPPIOCGDEBUG                int *
0x00005499  PPPIOCGSTAT                 struct ppp_stats *
0x0000549A  PPPIOCGTIME                 struct ppp_ddinfo *
0x0000549B  PPPIOCGXASYNCMAP            struct { int [8]; } *
0x0000549C  PPPIOCSXASYNCMAP            const struct { int [8]; } *
0x0000549D  PPPIOCSMRU                  const int *
0x0000549E  PPPIOCRASYNCMAP             const int *
0x0000549F  PPPIOCSMAXCID               const int *

// <include/linux/ipx.h>
0x000089E0  SIOCAIPXITFCRT              const char *
0x000089E1  SIOCAIPXPRISLT              const char *
0x000089E2  SIOCIPXCFGDATA              struct ipx_config_data *

// <include/linux/kd.h>
0x00004B60  GIO_FONT                    struct { char [8192]; } *
0x00004B61  PIO_FONT                    const struct { char [8192]; } *
0x00004B6B  GIO_FONTX                   struct console_font_desc *  // MORE I-O
0x00004B6C  PIO_FONTX                   const struct console_font_desc * //MORE
0x00004B70  GIO_CMAP                    struct { char [48]; } *
0x00004B71  PIO_CMAP                    const struct { char [48]; }
0x00004B2F  KIOCSOUND                   int
0x00004B30  KDMKTONE                    int
0x00004B31  KDGETLED                    char *
0x00004B32  KDSETLED                    int
0x00004B33  KDGKBTYPE                   char *
0x00004B34  KDADDIO                     int                             // MORE
0x00004B35  KDDELIO                     int                             // MORE
0x00004B36  KDENABIO                    void                            // MORE
0x00004B37  KDDISABIO                   void                            // MORE
0x00004B63  KDSKBMETA                   int
0x00004B64  KDGKBLED                    int *
0x00004B65  KDSKBLED                    int
0x00004B46  KDGKBENT                    struct kbentry *                // I-O
0x00004B47  KDSKBENT                    const struct kbentry *
0x00004B48  KDGKBSENT                   struct kbsentry *               // I-O
0x00004B49  KDSKBSENT                   const struct kbsentry *
0x00004B4A  KDGKBDIACR                  struct kbdiacrs *
0x00004B4B  KDSKBDIACR                  const struct kbdiacrs *
0x00004B4C  KDGETKEYCODE                struct kbkeycode *              // I-O
0x00004B4D  KDSETKEYCODE                const struct kbkeycode *
0x00004B4E  KDSIGACCEPT                 int

// <include/linux/lp.h>
0x00000601  LPCHAR                      int
0x00000602  LPTIME                      int
0x00000604  LPABORT                     int
0x00000605  LPSETIRQ                    int
0x00000606  LPGETIRQ                    int *
0x00000608  LPWAIT                      int
0x00000609  LPCAREFUL                   int
0x0000060A  LPABORTOPEN                 int
0x0000060B  LPGETSTATUS                 int *
0x0000060C  LPRESET                     void
0x0000060D  LPGETSTATS                  struct lp_stats *

// <include/linux/mroute.h>
0x000089E0  SIOCGETVIFCNT               struct sioc_vif_req *           // I-O
0x000089E1  SIOCGETSGCNT                struct sioc_sg_req *            // I-O

// <include/linux/mtio.h>
0x40086D01  MTIOCTOP                    const struct mtop *
0x801C6D02  MTIOCGET                    struct mtget *
0x80046D03  MTIOCPOS                    struct mtpos *
0x80206D04  MTIOCGETCONFIG              struct mtconfiginfo *
0x40206D05  MTIOCSETCONFIG              const struct mtconfiginfo *

// <include/linux/netrom.h>
0x000089E0  SIOCNRGETPARMS              struct nr_parms_struct *        // I-O
0x000089E1  SIOCNRSETPARMS              const struct nr_parms_struct *
0x000089E2  SIOCNRDECOBS                void
0x000089E3  SIOCNRRTCTL                 const int *

// <include/linux/sbpcd.h>
0x00009000  DDIOCSDBG                   const int *
0x00005382  CDROMAUDIOBUFSIZ            int

// <include/linux/scc.h>
0x00005470  TIOCSCCINI                  void
0x00005471  TIOCCHANINI                 const struct scc_modem *
0x00005472  TIOCGKISS                   struct ioctl_command *          // I-O
0x00005473  TIOCSKISS                   const struct ioctl_command *
0x00008910  SIOCGIFNAME                 char []
0x00008911  SIOCSIFLINK                 void
0x00008912  SIOCGIFCONF                 struct ifconf *         // MORE // I-O
0x00008913  SIOCGIFFLAGS                struct ifreq *                  // I-O
0x00008914  SIOCSIFFLAGS                const struct ifreq *
0x00008915  SIOCGIFADDR                 struct ifreq *                  // I-O
0x00008916  SIOCSIFADDR                 const struct ifreq *
0x00008917  SIOCGIFDSTADDR              struct ifreq *                  // I-O
0x00008918  SIOCSIFDSTADDR              const struct ifreq *
0x00008919  SIOCGIFBRDADDR              struct ifreq *                  // I-O
0x0000891A  SIOCSIFBRDADDR              const struct ifreq *
0x0000891B  SIOCGIFNETMASK              struct ifreq *                  // I-O
0x0000891C  SIOCSIFNETMASK              const struct ifreq *
0x0000891D  SIOCGIFMETRIC               struct ifreq *                  // I-O
0x0000891E  SIOCSIFMETRIC               const struct ifreq *
0x0000891F  SIOCGIFMEM                  struct ifreq *                  // I-O
0x00008920  SIOCSIFMEM                  const struct ifreq *
0x00008921  SIOCGIFMTU                  struct ifreq *                  // I-O
0x00008922  SIOCSIFMTU                  const struct ifreq *
0x00008923  OLD_SIOCGIFHWADDR           struct ifreq *                  // I-O
0x00008924  SIOCSIFHWADDR               const struct ifreq *            // MORE
0x00008925  SIOCGIFENCAP                int *
0x00008926  SIOCSIFENCAP                const int *
0x00008927  SIOCGIFHWADDR               struct ifreq *                  // I-O
0x00008929  SIOCGIFSLAVE                void
0x00008930  SIOCSIFSLAVE                void
0x00008931  SIOCADDMULTI                const struct ifreq *
0x00008932  SIOCDELMULTI                const struct ifreq *
0x00008940  SIOCADDRTOLD                void
0x00008941  SIOCDELRTOLD                void
0x00008950  SIOCDARP                    const struct arpreq *
0x00008951  SIOCGARP                    struct arpreq *                 // I-O
0x00008952  SIOCSARP                    const struct arpreq *
0x00008960  SIOCDRARP                   const struct arpreq *
0x00008961  SIOCGRARP                   struct arpreq *                 // I-O
0x00008962  SIOCSRARP                   const struct arpreq *
0x00008970  SIOCGIFMAP                  struct ifreq *                  // I-O
0x00008971  SIOCSIFMAP                  const struct ifreq *

// <include/linux/soundcard.h>
0x00005100  SNDCTL_SEQ_RESET            void
0x00005101  SNDCTL_SEQ_SYNC             void
0xC08C5102  SNDCTL_SYNTH_INFO           struct synth_info *             // I-O
0xC0045103  SNDCTL_SEQ_CTRLRATE         int *                           // I-O
0x80045104  SNDCTL_SEQ_GETOUTCOUNT      int *
0x80045105  SNDCTL_SEQ_GETINCOUNT       int *
0x40045106  SNDCTL_SEQ_PERCMODE         void
0x40285107  SNDCTL_FM_LOAD_INSTR        const struct sbi_instrument *
0x40045108  SNDCTL_SEQ_TESTMIDI         const int *
0x40045109  SNDCTL_SEQ_RESETSAMPLES     const int *
0x8004510A  SNDCTL_SEQ_NRSYNTHS         int *
0x8004510B  SNDCTL_SEQ_NRMIDIS          int *
0x40045408  SNDCTL_TMR_SELECT           int *                           // I-O
0xCFB85001  SNDCTL_PMGR_IFACE           struct patmgr_info *            // I-O
0xC0046D00  SNDCTL_MIDI_PRETIME         int *                           // I-O
0xC0046D01  SNDCTL_MIDI_MPUMODE         const int *
0xC0216D02  SNDCTL_MIDI_MPUCMD          struct mpu_command_rec *        // I-O
0x00005000  SNDCTL_DSP_RESET            void
0x00005001  SNDCTL_DSP_SYNC             void
0xC0045002  SNDCTL_DSP_SPEED            int *                           // I-O
0xC0045003  SNDCTL_DSP_STEREO           int *                           // I-O
0xC0045004  SNDCTL_DSP_GETBLKSIZE       int *                           // I-O
0xC0045006  SOUND_PCM_WRITE_CHANNELS    int *                           // I-O
0xC0045007  SOUND_PCM_WRITE_FILTER      int *                           // I-O
0x00005008  SNDCTL_DSP_POST             void
0xC0045009  SNDCTL_DSP_SUBDIVIDE        int *                           // I-O
0xC004500A  SNDCTL_DSP_SETFRAGMENT      int *                           // I-O
0x8004500B  SNDCTL_DSP_GETFMTS          int *
0xC0045005  SNDCTL_DSP_SETFMT           int *                           // I-O
0x800C500C  SNDCTL_DSP_GETOSPACE        struct audio_buf_info *
0x800C500D  SNDCTL_DSP_GETISPACE        struct audio_buf_info *
0x0000500E  SNDCTL_DSP_NONBLOCK         void
0x80045002  SOUND_PCM_READ_RATE         int *
0x80045006  SOUND_PCM_READ_CHANNELS     int *
0x80045005  SOUND_PCM_READ_BITS         int *
0x80045007  SOUND_PCM_READ_FILTER       int *
0x00004300  SNDCTL_COPR_RESET           void
0xCFB04301  SNDCTL_COPR_LOAD            const struct copr_buffer *
0xC0144302  SNDCTL_COPR_RDATA           struct copr_debug_buf *         // I-O
0xC0144303  SNDCTL_COPR_RCODE           struct copr_debug_buf *         // I-O
0x40144304  SNDCTL_COPR_WDATA           const struct copr_debug_buf *
0x40144305  SNDCTL_COPR_WCODE           const struct copr_debug_buf *
0xC0144306  SNDCTL_COPR_RUN             struct copr_debug_buf *         // I-O
0xC0144307  SNDCTL_COPR_HALT            struct copr_debug_buf *         // I-O
0x4FA44308  SNDCTL_COPR_SENDMSG         const struct copr_msg *
0x8FA44309  SNDCTL_COPR_RCVMSG          struct copr_msg *
0x80044D00  SOUND_MIXER_READ_VOLUME     int *
0x80044D01  SOUND_MIXER_READ_BASS       int *
0x80044D02  SOUND_MIXER_READ_TREBLE     int *
0x80044D03  SOUND_MIXER_READ_SYNTH      int *
0x80044D04  SOUND_MIXER_READ_PCM        int *
0x80044D05  SOUND_MIXER_READ_SPEAKER    int *
0x80044D06  SOUND_MIXER_READ_LINE       int *
0x80044D07  SOUND_MIXER_READ_MIC        int *
0x80044D08  SOUND_MIXER_READ_CD         int *
0x80044D09  SOUND_MIXER_READ_IMIX       int *
0x80044D0A  SOUND_MIXER_READ_ALTPCM     int *
0x80044D0B  SOUND_MIXER_READ_RECLEV     int *
0x80044D0C  SOUND_MIXER_READ_IGAIN      int *
0x80044D0D  SOUND_MIXER_READ_OGAIN      int *
0x80044D0E  SOUND_MIXER_READ_LINE1      int *
0x80044D0F  SOUND_MIXER_READ_LINE2      int *
0x80044D10  SOUND_MIXER_READ_LINE3      int *
0x80044D1C  SOUND_MIXER_READ_MUTE       int *
0xC0044D07  SOUND_MIXER_WRITE_MIC       int *                           // I-O
0xC0044D08  SOUND_MIXER_WRITE_CD        int *                           // I-O
0xC0044D09  SOUND_MIXER_WRITE_IMIX      int *                           // I-O
0xC0044D0A  SOUND_MIXER_WRITE_ALTPCM    int *                           // I-O
0xC0044D0B  SOUND_MIXER_WRITE_RECLEV    int *                           // I-O
0xC0044D0C  SOUND_MIXER_WRITE_IGAIN     int *                           // I-O
0xC0044D0D  SOUND_MIXER_WRITE_OGAIN     int *                           // I-O
0xC0044D0E  SOUND_MIXER_WRITE_LINE1     int *                           // I-O
0xC0044D0F  SOUND_MIXER_WRITE_LINE2     int *                           // I-O
0xC0044D10  SOUND_MIXER_WRITE_LINE3     int *                           // I-O
0xC0044D1C  SOUND_MIXER_WRITE_MUTE      int *                           // I-O
0xC0044D1D  SOUND_MIXER_WRITE_ENHANCE   int *                           // I-O
0xC0044D1E  SOUND_MIXER_WRITE_LOUD      int *                           // I-O
0xC0044DFF  SOUND_MIXER_WRITE_RECSRC    int *                           // I-O

// <include/linux/umsdos_fs.h>
0x000004D2  UMSDOS_READDIR_DOS          struct umsdos_ioctl *           // I-O
0x000004D3  UMSDOS_UNLINK_DOS           const struct umsdos_ioctl *
0x000004D4  UMSDOS_RMDIR_DOS            const struct umsdos_ioctl *
0x000004D5  UMSDOS_STAT_DOS             struct umsdos_ioctl *           // I-O
0x000004D6  UMSDOS_CREAT_EMD            const struct umsdos_ioctl *
0x000004D7  UMSDOS_UNLINK_EMD           const struct umsdos_ioctl *
0x000004D8  UMSDOS_READDIR_EMD          struct umsdos_ioctl *           // I-O
0x000004D9  UMSDOS_GETVERSION           struct umsdos_ioctl *
0x000004DA  UMSDOS_INIT_EMD             void
0x000004DB  UMSDOS_DOS_SETUP            const struct umsdos_ioctl *
0x000004DC  UMSDOS_RENAME_DOS           const struct umsdos_ioctl *

// <include/linux/vt.h>
0x00005600  VT_OPENQRY                  int *
0x00005601  VT_GETMODE                  struct vt_mode *
0x00005602  VT_SETMODE                  const struct vt_mode *
0x00005603  VT_GETSTATE                 struct vt_stat *
0x00005604  VT_SENDSIG                  void
0x00005605  VT_RELDISP                  int
0x00005606  VT_ACTIVATE                 int
0x00005607  VT_WAITACTIVE               int
0x00005608  VT_DISALLOCATE              int
0x00005609  VT_RESIZE                   const struct vt_sizes *
0x0000560A  VT_RESIZEX                  const struct vt_consize *

// More arguments.

Some ioctl's take a pointer to a structure which contains additional
pointers.  These are documented here in alphabetical order.

CDROMREADAUDIO takes an input pointer 'const struct cdrom_read_audio *'.
The 'buf' field points to an output buffer of length


            EQL_ENSLAVE                 const struct slaving_request *
            EQL_EMANCIPATE              const struct slaving_request *
            EQL_GETSLAVECFG             struct slave_config *           // I-O
            EQL_SETSLAVECFG             const struct slave_config *
            EQL_GETMASTERCFG            struct master_config *
            EQL_SETMASTERCFG            const struct master_config *

FDRAWCMD takes a 'struct floppy raw_cmd *'.  If 'flags & FD_RAW_WRITE'
is non-zero, then 'data' points to an input buffer of length 'length'.
If 'flags & FD_RAW_READ' is non-zero, then 'data' points to an output
buffer of length 'length'.

GIO_FONTX and PIO_FONTX take a 'struct console_font_desc *' or a
a buffer of 'char [charcount]'.  This is an output buffer for GIO_FONTX
and an input buffer for PIO_FONTX.

GIO_UNIMAP and PIO_UNIMAP take a 'struct unimapdesc *' or a
of 'struct unipair [entry_ct]'.  This is an output buffer for GIO_UNIMAP
and an input buffer for PIO_UNIMAP.

KDADDIO, KDDELIO, KDDISABIO, and KDENABIO enable or disable access to
I/O ports.  They are essentially alternate interfaces to 'ioperm'.

KDMAPDISP and KDUNMAPDISP enable or disable memory mappings or I/O port
access.  They are not implemented in the kernel.

SCSI_IOCTL_PROBE_HOST takes an input pointer 'const int *', which is a
length.  It uses the same pointer as an output pointer to a 'char []'
buffer of this length.

SIOCADDRT and SIOCDELRT take an input pointer whose type depends on
the protocol:

            Most protocols              const struct rtentry *
            AX.25                       const struct ax25_route *
            NET/ROM                     const struct nr_route_struct *

SIOCGIFCONF takes a 'struct ifconf *'.  The 'ifc_buf' field points to a
buffer of length 'ifc_len' bytes, into which the kernel writes a list of
type 'struct ifreq []'.

SIOCSIFHWADDR takes an input pointer whose type depends on the protocol:

            Most protocols              const struct ifreq *
            AX.25                       const char [AX25_ADDR_LEN]

TIOCLINUX takes a 'const char *'.  It uses this to distinguish several
independent sub-cases.  In the table below, 'N + foo' means 'foo' after
an N-byte pad.  'struct selection' is implicitly defined in

            TIOCLINUX-2                 1 + const struct selection *


0x00000001  FDSETPRM                    FIBMAP
0x00000002  FDDEFPRM                    FIGETBSZ
0x00005402  SNDCTL_TMR_START            TCSETS
0x00005403  SNDCTL_TMR_STOP             TCSETSW