1============= 2Ioctl Numbers 3============= 4 519 October 1999 6 7Michael Elizabeth Chastain 8<mec@shout.net> 9 10If you are adding new ioctl's to the kernel, you should use the _IO 11macros defined in <linux/ioctl.h>: 12 13 ====== == ============================================ 14 _IO an ioctl with no parameters 15 _IOW an ioctl with write parameters (copy_from_user) 16 _IOR an ioctl with read parameters (copy_to_user) 17 _IOWR an ioctl with both write and read parameters. 18 ====== == ============================================ 19 20'Write' and 'read' are from the user's point of view, just like the 21system calls 'write' and 'read'. For example, a SET_FOO ioctl would 22be _IOW, although the kernel would actually read data from user space; 23a GET_FOO ioctl would be _IOR, although the kernel would actually write 24data to user space. 25 26The first argument to _IO, _IOW, _IOR, or _IOWR is an identifying letter 27or number from the table below. Because of the large number of drivers, 28many drivers share a partial letter with other drivers. 29 30If you are writing a driver for a new device and need a letter, pick an 31unused block with enough room for expansion: 32 to 256 ioctl commands. 32You can register the block by patching this file and submitting the 33patch to Linus Torvalds. Or you can e-mail me at <mec@shout.net> and 34I'll register one for you. 35 36The second argument to _IO, _IOW, _IOR, or _IOWR is a sequence number 37to distinguish ioctls from each other. The third argument to _IOW, 38_IOR, or _IOWR is the type of the data going into the kernel or coming 39out of the kernel (e.g. 'int' or 'struct foo'). NOTE! Do NOT use 40sizeof(arg) as the third argument as this results in your ioctl thinking 41it passes an argument of type size_t. 42 43Some devices use their major number as the identifier; this is OK, as 44long as it is unique. Some devices are irregular and don't follow any 45convention at all. 46 47Following this convention is good because: 48 49(1) Keeping the ioctl's globally unique helps error checking: 50 if a program calls an ioctl on the wrong device, it will get an 51 error rather than some unexpected behaviour. 52 53(2) The 'strace' build procedure automatically finds ioctl numbers 54 defined with _IO, _IOW, _IOR, or _IOWR. 55 56(3) 'strace' can decode numbers back into useful names when the 57 numbers are unique. 58 59(4) People looking for ioctls can grep for them more easily when 60 this convention is used to define the ioctl numbers. 61 62(5) When following the convention, the driver code can use generic 63 code to copy the parameters between user and kernel space. 64 65This table lists ioctls visible from user land for Linux/x86. It contains 66most drivers up to 2.6.31, but I know I am missing some. There has been 67no attempt to list non-X86 architectures or ioctls from drivers/staging/. 68 69==== ===== ======================================================= ================================================================ 70Code Seq# Include File Comments 71 (hex) 72==== ===== ======================================================= ================================================================ 730x00 00-1F linux/fs.h conflict! 740x00 00-1F scsi/scsi_ioctl.h conflict! 750x00 00-1F linux/fb.h conflict! 760x00 00-1F linux/wavefront.h conflict! 770x02 all linux/fd.h 780x03 all linux/hdreg.h 790x04 D2-DC linux/umsdos_fs.h Dead since 2.6.11, but don't reuse these. 800x06 all linux/lp.h 810x07 9F-D0 linux/vmw_vmci_defs.h, uapi/linux/vm_sockets.h 820x09 all linux/raid/md_u.h 830x10 00-0F drivers/char/s390/vmcp.h 840x10 10-1F arch/s390/include/uapi/sclp_ctl.h 850x10 20-2F arch/s390/include/uapi/asm/hypfs.h 860x12 all linux/fs.h BLK* ioctls 87 linux/blkpg.h 880x15 all linux/fs.h FS_IOC_* ioctls 890x1b all InfiniBand Subsystem 90 <http://infiniband.sourceforge.net/> 910x20 all drivers/cdrom/cm206.h 920x22 all scsi/sg.h 930x3E 00-0F linux/counter.h <mailto:linux-iio@vger.kernel.org> 94'!' 00-1F uapi/linux/seccomp.h 95'#' 00-3F IEEE 1394 Subsystem 96 Block for the entire subsystem 97'$' 00-0F linux/perf_counter.h, linux/perf_event.h 98'%' 00-0F include/uapi/linux/stm.h System Trace Module subsystem 99 <mailto:alexander.shishkin@linux.intel.com> 100'&' 00-07 drivers/firewire/nosy-user.h 101'*' 00-1F uapi/linux/user_events.h User Events Subsystem 102 <mailto:linux-trace-kernel@vger.kernel.org> 103'1' 00-1F linux/timepps.h PPS kit from Ulrich Windl 104 <ftp://ftp.de.kernel.org/pub/linux/daemons/ntp/PPS/> 105'2' 01-04 linux/i2o.h 106'3' 00-0F drivers/s390/char/raw3270.h conflict! 107'3' 00-1F linux/suspend_ioctls.h, conflict! 108 kernel/power/user.c 109'8' all SNP8023 advanced NIC card 110 <mailto:mcr@solidum.com> 111';' 64-7F linux/vfio.h 112';' 80-FF linux/iommufd.h 113'=' 00-3f uapi/linux/ptp_clock.h <mailto:richardcochran@gmail.com> 114'@' 00-0F linux/radeonfb.h conflict! 115'@' 00-0F drivers/video/aty/aty128fb.c conflict! 116'A' 00-1F linux/apm_bios.h conflict! 117'A' 00-0F linux/agpgart.h, conflict! 118 drivers/char/agp/compat_ioctl.h 119'A' 00-7F sound/asound.h conflict! 120'B' 00-1F linux/cciss_ioctl.h conflict! 121'B' 00-0F include/linux/pmu.h conflict! 122'B' C0-FF advanced bbus <mailto:maassen@uni-freiburg.de> 123'B' 00-0F xen/xenbus_dev.h conflict! 124'C' all linux/soundcard.h conflict! 125'C' 01-2F linux/capi.h conflict! 126'C' F0-FF drivers/net/wan/cosa.h conflict! 127'D' all arch/s390/include/asm/dasd.h 128'D' 40-5F drivers/scsi/dpt/dtpi_ioctl.h Dead since 2022 129'D' 05 drivers/scsi/pmcraid.h 130'E' all linux/input.h conflict! 131'E' 00-0F xen/evtchn.h conflict! 132'F' all linux/fb.h conflict! 133'F' 01-02 drivers/scsi/pmcraid.h conflict! 134'F' 20 drivers/video/fsl-diu-fb.h conflict! 135'F' 20 linux/ivtvfb.h conflict! 136'F' 20 linux/matroxfb.h conflict! 137'F' 20 drivers/video/aty/atyfb_base.c conflict! 138'F' 00-0F video/da8xx-fb.h conflict! 139'F' 80-8F linux/arcfb.h conflict! 140'F' DD video/sstfb.h conflict! 141'G' 00-3F drivers/misc/sgi-gru/grulib.h conflict! 142'G' 00-0F xen/gntalloc.h, xen/gntdev.h conflict! 143'H' 00-7F linux/hiddev.h conflict! 144'H' 00-0F linux/hidraw.h conflict! 145'H' 01 linux/mei.h conflict! 146'H' 02 linux/mei.h conflict! 147'H' 03 linux/mei.h conflict! 148'H' 00-0F sound/asound.h conflict! 149'H' 20-40 sound/asound_fm.h conflict! 150'H' 80-8F sound/sfnt_info.h conflict! 151'H' 10-8F sound/emu10k1.h conflict! 152'H' 10-1F sound/sb16_csp.h conflict! 153'H' 10-1F sound/hda_hwdep.h conflict! 154'H' 40-4F sound/hdspm.h conflict! 155'H' 40-4F sound/hdsp.h conflict! 156'H' 90 sound/usb/usx2y/usb_stream.h 157'H' 00-0F uapi/misc/habanalabs.h conflict! 158'H' A0 uapi/linux/usb/cdc-wdm.h 159'H' C0-F0 net/bluetooth/hci.h conflict! 160'H' C0-DF net/bluetooth/hidp/hidp.h conflict! 161'H' C0-DF net/bluetooth/cmtp/cmtp.h conflict! 162'H' C0-DF net/bluetooth/bnep/bnep.h conflict! 163'H' F1 linux/hid-roccat.h <mailto:erazor_de@users.sourceforge.net> 164'H' F8-FA sound/firewire.h 165'I' all linux/isdn.h conflict! 166'I' 00-0F drivers/isdn/divert/isdn_divert.h conflict! 167'I' 40-4F linux/mISDNif.h conflict! 168'K' all linux/kd.h 169'L' 00-1F linux/loop.h conflict! 170'L' 10-1F drivers/scsi/mpt3sas/mpt3sas_ctl.h conflict! 171'L' E0-FF linux/ppdd.h encrypted disk device driver 172 <http://linux01.gwdg.de/~alatham/ppdd.html> 173'M' all linux/soundcard.h conflict! 174'M' 01-16 mtd/mtd-abi.h conflict! 175 and drivers/mtd/mtdchar.c 176'M' 01-03 drivers/scsi/megaraid/megaraid_sas.h 177'M' 00-0F drivers/video/fsl-diu-fb.h conflict! 178'N' 00-1F drivers/usb/scanner.h 179'N' 40-7F drivers/block/nvme.c 180'N' 80-8F uapi/linux/ntsync.h NT synchronization primitives 181 <mailto:wine-devel@winehq.org> 182'O' 00-06 mtd/ubi-user.h UBI 183'P' all linux/soundcard.h conflict! 184'P' 60-6F sound/sscape_ioctl.h conflict! 185'P' 00-0F drivers/usb/class/usblp.c conflict! 186'P' 01-09 drivers/misc/pci_endpoint_test.c conflict! 187'P' 00-0F xen/privcmd.h conflict! 188'P' 00-05 linux/tps6594_pfsm.h conflict! 189'Q' all linux/soundcard.h 190'R' 00-1F linux/random.h conflict! 191'R' 01 linux/rfkill.h conflict! 192'R' 20-2F linux/trace_mmap.h 193'R' C0-DF net/bluetooth/rfcomm.h 194'R' E0 uapi/linux/fsl_mc.h 195'S' all linux/cdrom.h conflict! 196'S' 80-81 scsi/scsi_ioctl.h conflict! 197'S' 82-FF scsi/scsi.h conflict! 198'S' 00-7F sound/asequencer.h conflict! 199'T' all linux/soundcard.h conflict! 200'T' 00-AF sound/asound.h conflict! 201'T' all arch/x86/include/asm/ioctls.h conflict! 202'T' C0-DF linux/if_tun.h conflict! 203'U' all sound/asound.h conflict! 204'U' 00-CF linux/uinput.h conflict! 205'U' 00-EF linux/usbdevice_fs.h 206'U' C0-CF drivers/bluetooth/hci_uart.h 207'V' all linux/vt.h conflict! 208'V' all linux/videodev2.h conflict! 209'V' C0 linux/ivtvfb.h conflict! 210'V' C0 linux/ivtv.h conflict! 211'V' C0 media/si4713.h conflict! 212'W' 00-1F linux/watchdog.h conflict! 213'W' 00-1F linux/wanrouter.h conflict! (pre 3.9) 214'W' 00-3F sound/asound.h conflict! 215'W' 40-5F drivers/pci/switch/switchtec.c 216'W' 60-61 linux/watch_queue.h 217'X' all fs/xfs/xfs_fs.h, conflict! 218 fs/xfs/linux-2.6/xfs_ioctl32.h, 219 include/linux/falloc.h, 220 linux/fs.h, 221'X' all fs/ocfs2/ocfs_fs.h conflict! 222'X' 01 linux/pktcdvd.h conflict! 223'Z' 14-15 drivers/message/fusion/mptctl.h 224'[' 00-3F linux/usb/tmc.h USB Test and Measurement Devices 225 <mailto:gregkh@linuxfoundation.org> 226'a' all linux/atm*.h, linux/sonet.h ATM on linux 227 <http://lrcwww.epfl.ch/> 228'a' 00-0F drivers/crypto/qat/qat_common/adf_cfg_common.h conflict! qat driver 229'b' 00-FF conflict! bit3 vme host bridge 230 <mailto:natalia@nikhefk.nikhef.nl> 231'b' 00-0F linux/dma-buf.h conflict! 232'c' 00-7F linux/comstats.h conflict! 233'c' 00-7F linux/coda.h conflict! 234'c' 00-1F linux/chio.h conflict! 235'c' 80-9F arch/s390/include/asm/chsc.h conflict! 236'c' A0-AF arch/x86/include/asm/msr.h conflict! 237'd' 00-FF linux/char/drm/drm.h conflict! 238'd' 02-40 pcmcia/ds.h conflict! 239'd' F0-FF linux/digi1.h 240'e' all linux/digi1.h conflict! 241'f' 00-1F linux/ext2_fs.h conflict! 242'f' 00-1F linux/ext3_fs.h conflict! 243'f' 00-0F fs/jfs/jfs_dinode.h conflict! 244'f' 00-0F fs/ext4/ext4.h conflict! 245'f' 00-0F linux/fs.h conflict! 246'f' 00-0F fs/ocfs2/ocfs2_fs.h conflict! 247'f' 13-27 linux/fscrypt.h 248'f' 81-8F linux/fsverity.h 249'g' 00-0F linux/usb/gadgetfs.h 250'g' 20-2F linux/usb/g_printer.h 251'h' 00-7F conflict! Charon filesystem 252 <mailto:zapman@interlan.net> 253'h' 00-1F linux/hpet.h conflict! 254'h' 80-8F fs/hfsplus/ioctl.c 255'i' 00-3F linux/i2o-dev.h conflict! 256'i' 0B-1F linux/ipmi.h conflict! 257'i' 80-8F linux/i8k.h 258'i' 90-9F `linux/iio/*.h` IIO 259'j' 00-3F linux/joystick.h 260'k' 00-0F linux/spi/spidev.h conflict! 261'k' 00-05 video/kyro.h conflict! 262'k' 10-17 linux/hsi/hsi_char.h HSI character device 263'l' 00-3F linux/tcfs_fs.h transparent cryptographic file system 264 <http://web.archive.org/web/%2A/http://mikonos.dia.unisa.it/tcfs> 265'l' 40-7F linux/udf_fs_i.h in development: 266 <https://github.com/pali/udftools> 267'm' 00-09 linux/mmtimer.h conflict! 268'm' all linux/mtio.h conflict! 269'm' all linux/soundcard.h conflict! 270'm' all linux/synclink.h conflict! 271'm' 00-19 drivers/message/fusion/mptctl.h conflict! 272'm' 00 drivers/scsi/megaraid/megaraid_ioctl.h conflict! 273'n' 00-7F linux/ncp_fs.h and fs/ncpfs/ioctl.c 274'n' 80-8F uapi/linux/nilfs2_api.h NILFS2 275'n' E0-FF linux/matroxfb.h matroxfb 276'o' 00-1F fs/ocfs2/ocfs2_fs.h OCFS2 277'o' 00-03 mtd/ubi-user.h conflict! (OCFS2 and UBI overlaps) 278'o' 40-41 mtd/ubi-user.h UBI 279'o' 01-A1 `linux/dvb/*.h` DVB 280'p' 00-0F linux/phantom.h conflict! (OpenHaptics needs this) 281'p' 00-1F linux/rtc.h conflict! 282'p' 40-7F linux/nvram.h 283'p' 80-9F linux/ppdev.h user-space parport 284 <mailto:tim@cyberelk.net> 285'p' A1-A5 linux/pps.h LinuxPPS 286 <mailto:giometti@linux.it> 287'q' 00-1F linux/serio.h 288'q' 80-FF linux/telephony.h Internet PhoneJACK, Internet LineJACK 289 linux/ixjuser.h <http://web.archive.org/web/%2A/http://www.quicknet.net> 290'r' 00-1F linux/msdos_fs.h and fs/fat/dir.c 291's' all linux/cdk.h 292't' 00-7F linux/ppp-ioctl.h 293't' 80-8F linux/isdn_ppp.h 294't' 90-91 linux/toshiba.h toshiba and toshiba_acpi SMM 295'u' 00-1F linux/smb_fs.h gone 296'u' 00-2F linux/ublk_cmd.h conflict! 297'u' 20-3F linux/uvcvideo.h USB video class host driver 298'u' 40-4f linux/udmabuf.h userspace dma-buf misc device 299'v' 00-1F linux/ext2_fs.h conflict! 300'v' 00-1F linux/fs.h conflict! 301'v' 00-0F linux/sonypi.h conflict! 302'v' 00-0F media/v4l2-subdev.h conflict! 303'v' 20-27 arch/powerpc/include/uapi/asm/vas-api.h VAS API 304'v' C0-FF linux/meye.h conflict! 305'w' all CERN SCI driver 306'y' 00-1F packet based user level communications 307 <mailto:zapman@interlan.net> 308'z' 00-3F CAN bus card conflict! 309 <mailto:hdstich@connectu.ulm.circular.de> 310'z' 40-7F CAN bus card conflict! 311 <mailto:oe@port.de> 312'z' 10-4F drivers/s390/crypto/zcrypt_api.h conflict! 313'|' 00-7F linux/media.h 3140x80 00-1F linux/fb.h 3150x81 00-1F linux/vduse.h 3160x89 00-06 arch/x86/include/asm/sockios.h 3170x89 0B-DF linux/sockios.h 3180x89 E0-EF linux/sockios.h SIOCPROTOPRIVATE range 3190x89 F0-FF linux/sockios.h SIOCDEVPRIVATE range 3200x8A 00-1F linux/eventpoll.h 3210x8B all linux/wireless.h 3220x8C 00-3F WiNRADiO driver 323 <http://www.winradio.com.au/> 3240x90 00 drivers/cdrom/sbpcd.h 3250x92 00-0F drivers/usb/mon/mon_bin.c 3260x93 60-7F linux/auto_fs.h 3270x94 all fs/btrfs/ioctl.h Btrfs filesystem 328 and linux/fs.h some lifted to vfs/generic 3290x97 00-7F fs/ceph/ioctl.h Ceph file system 3300x99 00-0F 537-Addinboard driver 331 <mailto:buk@buks.ipn.de> 3320xA0 all linux/sdp/sdp.h Industrial Device Project 333 <mailto:kenji@bitgate.com> 3340xA1 0 linux/vtpm_proxy.h TPM Emulator Proxy Driver 3350xA2 all uapi/linux/acrn.h ACRN hypervisor 3360xA3 80-8F Port ACL in development: 337 <mailto:tlewis@mindspring.com> 3380xA3 90-9F linux/dtlk.h 3390xA4 00-1F uapi/linux/tee.h Generic TEE subsystem 3400xA4 00-1F uapi/asm/sgx.h <mailto:linux-sgx@vger.kernel.org> 3410xA5 01-05 linux/surface_aggregator/cdev.h Microsoft Surface Platform System Aggregator 342 <mailto:luzmaximilian@gmail.com> 3430xA5 20-2F linux/surface_aggregator/dtx.h Microsoft Surface DTX driver 344 <mailto:luzmaximilian@gmail.com> 3450xAA 00-3F linux/uapi/linux/userfaultfd.h 3460xAB 00-1F linux/nbd.h 3470xAC 00-1F linux/raw.h 3480xAD 00 Netfilter device in development: 349 <mailto:rusty@rustcorp.com.au> 3500xAE 00-1F linux/kvm.h Kernel-based Virtual Machine 351 <mailto:kvm@vger.kernel.org> 3520xAE 40-FF linux/kvm.h Kernel-based Virtual Machine 353 <mailto:kvm@vger.kernel.org> 3540xAE 20-3F linux/nitro_enclaves.h Nitro Enclaves 3550xAF 00-1F linux/fsl_hypervisor.h Freescale hypervisor 3560xB0 all RATIO devices in development: 357 <mailto:vgo@ratio.de> 3580xB1 00-1F PPPoX 359 <mailto:mostrows@styx.uwaterloo.ca> 3600xB2 00 arch/powerpc/include/uapi/asm/papr-vpd.h powerpc/pseries VPD API 361 <mailto:linuxppc-dev> 3620xB2 01-02 arch/powerpc/include/uapi/asm/papr-sysparm.h powerpc/pseries system parameter API 363 <mailto:linuxppc-dev> 3640xB3 00 linux/mmc/ioctl.h 3650xB4 00-0F linux/gpio.h <mailto:linux-gpio@vger.kernel.org> 3660xB5 00-0F uapi/linux/rpmsg.h <mailto:linux-remoteproc@vger.kernel.org> 3670xB6 all linux/fpga-dfl.h 3680xB7 all uapi/linux/remoteproc_cdev.h <mailto:linux-remoteproc@vger.kernel.org> 3690xB7 all uapi/linux/nsfs.h <mailto:Andrei Vagin <avagin@openvz.org>> 3700xB8 01-02 uapi/misc/mrvl_cn10k_dpi.h Marvell CN10K DPI driver 3710xC0 00-0F linux/usb/iowarrior.h 3720xCA 00-0F uapi/misc/cxl.h 3730xCA 10-2F uapi/misc/ocxl.h 3740xCA 80-BF uapi/scsi/cxlflash_ioctl.h 3750xCB 00-1F CBM serial IEC bus in development: 376 <mailto:michael.klein@puffin.lb.shuttle.de> 3770xCC 00-0F drivers/misc/ibmvmc.h pseries VMC driver 3780xCD 01 linux/reiserfs_fs.h Dead since 6.13 3790xCE 01-02 uapi/linux/cxl_mem.h Compute Express Link Memory Devices 3800xCF 02 fs/smb/client/cifs_ioctl.h 3810xDB 00-0F drivers/char/mwave/mwavepub.h 3820xDD 00-3F ZFCP device driver see drivers/s390/scsi/ 383 <mailto:aherrman@de.ibm.com> 3840xE5 00-3F linux/fuse.h 3850xEC 00-01 drivers/platform/chrome/cros_ec_dev.h ChromeOS EC driver 3860xEE 00-09 uapi/linux/pfrut.h Platform Firmware Runtime Update and Telemetry 3870xF3 00-3F drivers/usb/misc/sisusbvga/sisusb.h sisfb (in development) 388 <mailto:thomas@winischhofer.net> 3890xF6 all LTTng Linux Trace Toolkit Next Generation 390 <mailto:mathieu.desnoyers@efficios.com> 3910xF8 all arch/x86/include/uapi/asm/amd_hsmp.h AMD HSMP EPYC system management interface driver 392 <mailto:nchatrad@amd.com> 3930xFD all linux/dm-ioctl.h 3940xFE all linux/isst_if.h 395==== ===== ======================================================= ================================================================ 396