projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
1 | Ioctl Numbers |
| 2 | 19 October 1999 | |
| 3 | Michael Elizabeth Chastain | |
| 4 | <[email protected]> | |
| 5 | ||
| 6 | If you are adding new ioctl's to the kernel, you should use the _IO | |
| 7 | macros defined in <linux/ioctl.h>: | |
| 8 | ||
| 9 | _IO an ioctl with no parameters | |
| 10 | _IOW an ioctl with write parameters (copy_from_user) | |
| 11 | _IOR an ioctl with read parameters (copy_to_user) | |
| 12 | _IOWR an ioctl with both write and read parameters. | |
| 13 | ||
| 14 | 'Write' and 'read' are from the user's point of view, just like the | |
| 15 | system calls 'write' and 'read'. For example, a SET_FOO ioctl would | |
| 16 | be _IOW, although the kernel would actually read data from user space; | |
| 17 | a GET_FOO ioctl would be _IOR, although the kernel would actually write | |
| 18 | data to user space. | |
| 19 | ||
| 20 | The first argument to _IO, _IOW, _IOR, or _IOWR is an identifying letter | |
| 21 | or number from the table below. Because of the large number of drivers, | |
| 22 | many drivers share a partial letter with other drivers. | |
| 23 | ||
| 24 | If you are writing a driver for a new device and need a letter, pick an | |
| 25 | unused block with enough room for expansion: 32 to 256 ioctl commands. | |
| 26 | You can register the block by patching this file and submitting the | |
| 27 | patch to Linus Torvalds. Or you can e-mail me at <[email protected]> and | |
| 28 | I'll register one for you. | |
| 29 | ||
| 30 | The second argument to _IO, _IOW, _IOR, or _IOWR is a sequence number | |
| 31 | to distinguish ioctls from each other. The third argument to _IOW, | |
| 32 | _IOR, or _IOWR is the type of the data going into the kernel or coming | |
| 33 | out of the kernel (e.g. 'int' or 'struct foo'). NOTE! Do NOT use | |
| 34 | sizeof(arg) as the third argument as this results in your ioctl thinking | |
| 35 | it passes an argument of type size_t. | |
| 36 | ||
| 37 | Some devices use their major number as the identifier; this is OK, as | |
| 38 | long as it is unique. Some devices are irregular and don't follow any | |
| 39 | convention at all. | |
| 40 | ||
| 41 | Following this convention is good because: | |
| 42 | ||
| 43 | (1) Keeping the ioctl's globally unique helps error checking: | |
| 44 | if a program calls an ioctl on the wrong device, it will get an | |
| 45 | error rather than some unexpected behaviour. | |
| 46 | ||
| 47 | (2) The 'strace' build procedure automatically finds ioctl numbers | |
| 48 | defined with _IO, _IOW, _IOR, or _IOWR. | |
| 49 | ||
| 50 | (3) 'strace' can decode numbers back into useful names when the | |
| 51 | numbers are unique. | |
| 52 | ||
| 53 | (4) People looking for ioctls can grep for them more easily when | |
| 54 | this convention is used to define the ioctl numbers. | |
| 55 | ||
| 56 | (5) When following the convention, the driver code can use generic | |
| 57 | code to copy the parameters between user and kernel space. | |
| 58 | ||
| 59 | This table lists ioctls visible from user land for Linux/i386. It contains | |
| 60 | most drivers up to 2.3.14, but I know I am missing some. | |
| 61 | ||
| 62 | Code Seq# Include File Comments | |
| 63 | ======================================================== | |
| 64 | 0x00 00-1F linux/fs.h conflict! | |
| 65 | 0x00 00-1F scsi/scsi_ioctl.h conflict! | |
| 66 | 0x00 00-1F linux/fb.h conflict! | |
| 67 | 0x00 00-1F linux/wavefront.h conflict! | |
| 68 | 0x02 all linux/fd.h | |
| 69 | 0x03 all linux/hdreg.h | |
| 70 | 0x04 all linux/umsdos_fs.h | |
| 71 | 0x06 all linux/lp.h | |
| 72 | 0x09 all linux/md.h | |
| 73 | 0x12 all linux/fs.h | |
| 74 | linux/blkpg.h | |
| 75 | 0x1b all InfiniBand Subsystem <http://www.openib.org/> | |
| 76 | 0x20 all drivers/cdrom/cm206.h | |
| 77 | 0x22 all scsi/sg.h | |
| 78 | '#' 00-3F IEEE 1394 Subsystem Block for the entire subsystem | |
| 79 | '1' 00-1F <linux/timepps.h> PPS kit from Ulrich Windl | |
| 80 | <ftp://ftp.de.kernel.org/pub/linux/daemons/ntp/PPS/> | |
| 1da177e4 LT |
81 | '8' all SNP8023 advanced NIC card |
| 82 | <mailto:[email protected]> | |
| 83 | 'A' 00-1F linux/apm_bios.h | |
| 84 | 'B' C0-FF advanced bbus | |
| 85 | <mailto:[email protected]> | |
| 86 | 'C' all linux/soundcard.h | |
| 87 | 'D' all asm-s390/dasd.h | |
| 88 | 'F' all linux/fb.h | |
| 89 | 'I' all linux/isdn.h | |
| 90 | 'J' 00-1F drivers/scsi/gdth_ioctl.h | |
| 91 | 'K' all linux/kd.h | |
| 92 | 'L' 00-1F linux/loop.h | |
| 93 | 'L' E0-FF linux/ppdd.h encrypted disk device driver | |
| 94 | <http://linux01.gwdg.de/~alatham/ppdd.html> | |
| 95 | 'M' all linux/soundcard.h conflict! | |
| 96 | 'M' 00-1F linux/isicom.h conflict! | |
| 97 | 'N' 00-1F drivers/usb/scanner.h | |
| 98 | 'P' all linux/soundcard.h | |
| 99 | 'Q' all linux/soundcard.h | |
| 100 | 'R' 00-1F linux/random.h | |
| 101 | 'S' all linux/cdrom.h conflict! | |
| 102 | 'S' 80-81 scsi/scsi_ioctl.h conflict! | |
| 103 | 'S' 82-FF scsi/scsi.h conflict! | |
| 104 | 'T' all linux/soundcard.h conflict! | |
| 105 | 'T' all asm-i386/ioctls.h conflict! | |
| 106 | 'U' 00-EF linux/drivers/usb/usb.h | |
| 107 | 'U' F0-FF drivers/usb/auerswald.c | |
| 108 | 'V' all linux/vt.h | |
| 109 | 'W' 00-1F linux/watchdog.h conflict! | |
| 110 | 'W' 00-1F linux/wanrouter.h conflict! | |
| 111 | 'X' all linux/xfs_fs.h | |
| 112 | 'Y' all linux/cyclades.h | |
| 113 | 'a' all ATM on linux | |
| 114 | <http://lrcwww.epfl.ch/linux-atm/magic.html> | |
| 115 | 'b' 00-FF bit3 vme host bridge | |
| 116 | <mailto:[email protected]> | |
| 117 | 'c' 00-7F linux/comstats.h conflict! | |
| 118 | 'c' 00-7F linux/coda.h conflict! | |
| 119 | 'd' 00-FF linux/char/drm/drm/h conflict! | |
| 120 | 'd' 00-1F linux/devfs_fs.h conflict! | |
| 121 | 'd' 00-DF linux/video_decoder.h conflict! | |
| 122 | 'd' F0-FF linux/digi1.h | |
| 123 | 'e' all linux/digi1.h conflict! | |
| 124 | 'e' 00-1F linux/video_encoder.h conflict! | |
| 125 | 'e' 00-1F net/irda/irtty.h conflict! | |
| 126 | 'f' 00-1F linux/ext2_fs.h | |
| 127 | 'h' 00-7F Charon filesystem | |
| 128 | <mailto:[email protected]> | |
| 129 | 'i' 00-3F linux/i2o.h | |
| 130 | 'j' 00-3F linux/joystick.h | |
| 1da177e4 LT |
131 | 'l' 00-3F linux/tcfs_fs.h transparent cryptographic file system |
| 132 | <http://mikonos.dia.unisa.it/tcfs> | |
| 133 | 'l' 40-7F linux/udf_fs_i.h in development: | |
| 98766fbe | 134 | <http://sourceforge.net/projects/linux-udf/> |
| 1da177e4 LT |
135 | 'm' all linux/mtio.h conflict! |
| 136 | 'm' all linux/soundcard.h conflict! | |
| 137 | 'm' all linux/synclink.h conflict! | |
| 138 | 'm' 00-1F net/irda/irmod.h conflict! | |
| 139 | 'n' 00-7F linux/ncp_fs.h | |
| 140 | 'n' E0-FF video/matrox.h matroxfb | |
| 141 | 'p' 00-3F linux/mc146818rtc.h | |
| 142 | 'p' 40-7F linux/nvram.h | |
| 143 | 'p' 80-9F user-space parport | |
| 144 | <mailto:[email protected]> | |
| 145 | 'q' 00-1F linux/serio.h | |
| 146 | 'q' 80-FF Internet PhoneJACK, Internet LineJACK | |
| 147 | <http://www.quicknet.net> | |
| 148 | 'r' 00-1F linux/msdos_fs.h | |
| 149 | 's' all linux/cdk.h | |
| 150 | 't' 00-7F linux/if_ppp.h | |
| 151 | 't' 80-8F linux/isdn_ppp.h | |
| 152 | 'u' 00-1F linux/smb_fs.h | |
| 153 | 'v' 00-1F linux/ext2_fs.h conflict! | |
| 154 | 'v' all linux/videodev.h conflict! | |
| 155 | 'w' all CERN SCI driver | |
| 156 | 'y' 00-1F packet based user level communications | |
| 157 | <mailto:[email protected]> | |
| 158 | 'z' 00-3F CAN bus card | |
| 159 | <mailto:[email protected]> | |
| 160 | 'z' 40-7F CAN bus card | |
| 161 | <mailto:[email protected]> | |
| 162 | 0x80 00-1F linux/fb.h | |
| 163 | 0x81 00-1F linux/videotext.h | |
| 164 | 0x89 00-06 asm-i386/sockios.h | |
| 165 | 0x89 0B-DF linux/sockios.h | |
| 166 | 0x89 E0-EF linux/sockios.h SIOCPROTOPRIVATE range | |
| 167 | 0x89 F0-FF linux/sockios.h SIOCDEVPRIVATE range | |
| 168 | 0x8B all linux/wireless.h | |
| 169 | 0x8C 00-3F WiNRADiO driver | |
| 170 | <http://www.proximity.com.au/~brian/winradio/> | |
| 171 | 0x90 00 drivers/cdrom/sbpcd.h | |
| 172 | 0x93 60-7F linux/auto_fs.h | |
| 173 | 0x99 00-0F 537-Addinboard driver | |
| 174 | <mailto:[email protected]> | |
| 175 | 0xA0 all linux/sdp/sdp.h Industrial Device Project | |
| 176 | <mailto:[email protected]> | |
| 177 | 0xA3 80-8F Port ACL in development: | |
| 178 | <mailto:[email protected]> | |
| 179 | 0xA3 90-9F linux/dtlk.h | |
| 180 | 0xAB 00-1F linux/nbd.h | |
| 181 | 0xAC 00-1F linux/raw.h | |
| 182 | 0xAD 00 Netfilter device in development: | |
| 183 | <mailto:[email protected]> | |
| 184 | 0xB0 all RATIO devices in development: | |
| 185 | <mailto:[email protected]> | |
| 186 | 0xB1 00-1F PPPoX <mailto:[email protected]> | |
| 187 | 0xCB 00-1F CBM serial IEC bus in development: | |
| 188 | <mailto:[email protected]> | |
| 189 | 0xDD 00-3F ZFCP device driver see drivers/s390/scsi/ | |
| 190 | <mailto:[email protected]> | |
| 191 | 0xF3 00-3F video/sisfb.h sisfb (in development) | |
| 192 | <mailto:[email protected]> |