3
Michael Elizabeth Chastain
6
If you are adding new ioctl's to the kernel, you should use the _IO
7
macros defined in <linux/ioctl.h>:
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.
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
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.
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 <mec@shout.net> and
28
I'll register one for you.
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.
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
41
Following this convention is good because:
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.
47
(2) The 'strace' build procedure automatically finds ioctl numbers
48
defined with _IO, _IOW, _IOR, or _IOWR.
50
(3) 'strace' can decode numbers back into useful names when the
53
(4) People looking for ioctls can grep for them more easily when
54
this convention is used to define the ioctl numbers.
56
(5) When following the convention, the driver code can use generic
57
code to copy the parameters between user and kernel space.
59
This table lists ioctls visible from user land for Linux/x86. It contains
60
most drivers up to 2.6.31, but I know I am missing some. There has been
61
no attempt to list non-X86 architectures or ioctls from drivers/staging/.
63
Code Seq#(hex) Include File Comments
64
========================================================
65
0x00 00-1F linux/fs.h conflict!
66
0x00 00-1F scsi/scsi_ioctl.h conflict!
67
0x00 00-1F linux/fb.h conflict!
68
0x00 00-1F linux/wavefront.h conflict!
70
0x03 all linux/hdreg.h
71
0x04 D2-DC linux/umsdos_fs.h Dead since 2.6.11, but don't reuse these.
73
0x09 all linux/raid/md_u.h
74
0x10 00-0F drivers/char/s390/vmcp.h
77
0x1b all InfiniBand Subsystem <http://infiniband.sourceforge.net/>
78
0x20 all drivers/cdrom/cm206.h
80
'#' 00-3F IEEE 1394 Subsystem Block for the entire subsystem
81
'$' 00-0F linux/perf_counter.h, linux/perf_event.h
82
'&' 00-07 drivers/firewire/nosy-user.h
83
'1' 00-1F <linux/timepps.h> PPS kit from Ulrich Windl
84
<ftp://ftp.de.kernel.org/pub/linux/daemons/ntp/PPS/>
86
'3' 00-0F drivers/s390/char/raw3270.h conflict!
87
'3' 00-1F linux/suspend_ioctls.h conflict!
88
and kernel/power/user.c
89
'8' all SNP8023 advanced NIC card
90
<mailto:mcr@solidum.com>
91
'@' 00-0F linux/radeonfb.h conflict!
92
'@' 00-0F drivers/video/aty/aty128fb.c conflict!
93
'A' 00-1F linux/apm_bios.h conflict!
94
'A' 00-0F linux/agpgart.h conflict!
95
and drivers/char/agp/compat_ioctl.h
96
'A' 00-7F sound/asound.h conflict!
97
'B' 00-1F linux/cciss_ioctl.h conflict!
98
'B' 00-0F include/linux/pmu.h conflict!
99
'B' C0-FF advanced bbus
100
<mailto:maassen@uni-freiburg.de>
101
'C' all linux/soundcard.h conflict!
102
'C' 01-2F linux/capi.h conflict!
103
'C' F0-FF drivers/net/wan/cosa.h conflict!
104
'D' all arch/s390/include/asm/dasd.h
105
'D' 40-5F drivers/scsi/dpt/dtpi_ioctl.h
106
'D' 05 drivers/scsi/pmcraid.h
107
'E' all linux/input.h conflict!
108
'E' 00-0F xen/evtchn.h conflict!
109
'F' all linux/fb.h conflict!
110
'F' 01-02 drivers/scsi/pmcraid.h conflict!
111
'F' 20 drivers/video/fsl-diu-fb.h conflict!
112
'F' 20 drivers/video/intelfb/intelfb.h conflict!
113
'F' 20 linux/ivtvfb.h conflict!
114
'F' 20 linux/matroxfb.h conflict!
115
'F' 20 drivers/video/aty/atyfb_base.c conflict!
116
'F' 00-0F video/da8xx-fb.h conflict!
117
'F' 80-8F linux/arcfb.h conflict!
118
'F' DD video/sstfb.h conflict!
119
'G' 00-3F drivers/misc/sgi-gru/grulib.h conflict!
120
'G' 00-0F linux/gigaset_dev.h conflict!
121
'H' 00-7F linux/hiddev.h conflict!
122
'H' 00-0F linux/hidraw.h conflict!
123
'H' 00-0F sound/asound.h conflict!
124
'H' 20-40 sound/asound_fm.h conflict!
125
'H' 80-8F sound/sfnt_info.h conflict!
126
'H' 10-8F sound/emu10k1.h conflict!
127
'H' 10-1F sound/sb16_csp.h conflict!
128
'H' 10-1F sound/hda_hwdep.h conflict!
129
'H' 40-4F sound/hdspm.h conflict!
130
'H' 40-4F sound/hdsp.h conflict!
131
'H' 90 sound/usb/usx2y/usb_stream.h
132
'H' C0-F0 net/bluetooth/hci.h conflict!
133
'H' C0-DF net/bluetooth/hidp/hidp.h conflict!
134
'H' C0-DF net/bluetooth/cmtp/cmtp.h conflict!
135
'H' C0-DF net/bluetooth/bnep/bnep.h conflict!
136
'H' F1 linux/hid-roccat.h <mailto:erazor_de@users.sourceforge.net>
137
'I' all linux/isdn.h conflict!
138
'I' 00-0F drivers/isdn/divert/isdn_divert.h conflict!
139
'I' 40-4F linux/mISDNif.h conflict!
140
'J' 00-1F drivers/scsi/gdth_ioctl.h
142
'L' 00-1F linux/loop.h conflict!
143
'L' 10-1F drivers/scsi/mpt2sas/mpt2sas_ctl.h conflict!
144
'L' E0-FF linux/ppdd.h encrypted disk device driver
145
<http://linux01.gwdg.de/~alatham/ppdd.html>
146
'M' all linux/soundcard.h conflict!
147
'M' 01-16 mtd/mtd-abi.h conflict!
148
and drivers/mtd/mtdchar.c
149
'M' 01-03 drivers/scsi/megaraid/megaraid_sas.h
150
'M' 00-0F drivers/video/fsl-diu-fb.h conflict!
151
'N' 00-1F drivers/usb/scanner.h
152
'O' 00-06 mtd/ubi-user.h UBI
153
'P' all linux/soundcard.h conflict!
154
'P' 60-6F sound/sscape_ioctl.h conflict!
155
'P' 00-0F drivers/usb/class/usblp.c conflict!
156
'Q' all linux/soundcard.h
157
'R' 00-1F linux/random.h conflict!
158
'R' 01 linux/rfkill.h conflict!
159
'R' C0-DF net/bluetooth/rfcomm.h
160
'S' all linux/cdrom.h conflict!
161
'S' 80-81 scsi/scsi_ioctl.h conflict!
162
'S' 82-FF scsi/scsi.h conflict!
163
'S' 00-7F sound/asequencer.h conflict!
164
'T' all linux/soundcard.h conflict!
165
'T' 00-AF sound/asound.h conflict!
166
'T' all arch/x86/include/asm/ioctls.h conflict!
167
'T' C0-DF linux/if_tun.h conflict!
168
'U' all sound/asound.h conflict!
169
'U' 00-CF linux/uinput.h conflict!
170
'U' 00-EF linux/usbdevice_fs.h
171
'U' C0-CF drivers/bluetooth/hci_uart.h
172
'V' all linux/vt.h conflict!
173
'V' all linux/videodev2.h conflict!
174
'V' C0 linux/ivtvfb.h conflict!
175
'V' C0 linux/ivtv.h conflict!
176
'V' C0 media/davinci/vpfe_capture.h conflict!
177
'V' C0 media/si4713.h conflict!
178
'V' C0-CF drivers/media/video/mxb.h conflict!
179
'W' 00-1F linux/watchdog.h conflict!
180
'W' 00-1F linux/wanrouter.h conflict!
181
'W' 00-3F sound/asound.h conflict!
182
'X' all fs/xfs/xfs_fs.h conflict!
183
and fs/xfs/linux-2.6/xfs_ioctl32.h
184
and include/linux/falloc.h
186
'X' all fs/ocfs2/ocfs_fs.h conflict!
187
'X' 01 linux/pktcdvd.h conflict!
188
'Y' all linux/cyclades.h
189
'Z' 14-15 drivers/message/fusion/mptctl.h
190
'[' 00-07 linux/usb/tmc.h USB Test and Measurement Devices
191
<mailto:gregkh@suse.de>
192
'a' all linux/atm*.h, linux/sonet.h ATM on linux
193
<http://lrcwww.epfl.ch/>
194
'b' 00-FF conflict! bit3 vme host bridge
195
<mailto:natalia@nikhefk.nikhef.nl>
196
'c' all linux/cm4000_cs.h conflict!
197
'c' 00-7F linux/comstats.h conflict!
198
'c' 00-7F linux/coda.h conflict!
199
'c' 00-1F linux/chio.h conflict!
200
'c' 80-9F arch/s390/include/asm/chsc.h conflict!
201
'c' A0-AF arch/x86/include/asm/msr.h conflict!
202
'd' 00-FF linux/char/drm/drm/h conflict!
203
'd' 02-40 pcmcia/ds.h conflict!
204
'd' 10-3F drivers/media/video/dabusb.h conflict!
205
'd' C0-CF drivers/media/video/saa7191.h conflict!
206
'd' F0-FF linux/digi1.h
207
'e' all linux/digi1.h conflict!
208
'e' 00-1F drivers/net/irda/irtty-sir.h conflict!
209
'f' 00-1F linux/ext2_fs.h conflict!
210
'f' 00-1F linux/ext3_fs.h conflict!
211
'f' 00-0F fs/jfs/jfs_dinode.h conflict!
212
'f' 00-0F fs/ext4/ext4.h conflict!
213
'f' 00-0F linux/fs.h conflict!
214
'f' 00-0F fs/ocfs2/ocfs2_fs.h conflict!
215
'g' 00-0F linux/usb/gadgetfs.h
216
'g' 20-2F linux/usb/g_printer.h
217
'h' 00-7F conflict! Charon filesystem
218
<mailto:zapman@interlan.net>
219
'h' 00-1F linux/hpet.h conflict!
220
'i' 00-3F linux/i2o-dev.h conflict!
221
'i' 0B-1F linux/ipmi.h conflict!
222
'i' 80-8F linux/i8k.h
223
'j' 00-3F linux/joystick.h
224
'k' 00-0F linux/spi/spidev.h conflict!
225
'k' 00-05 video/kyro.h conflict!
226
'l' 00-3F linux/tcfs_fs.h transparent cryptographic file system
227
<http://web.archive.org/web/*/http://mikonos.dia.unisa.it/tcfs>
228
'l' 40-7F linux/udf_fs_i.h in development:
229
<http://sourceforge.net/projects/linux-udf/>
230
'm' 00-09 linux/mmtimer.h conflict!
231
'm' all linux/mtio.h conflict!
232
'm' all linux/soundcard.h conflict!
233
'm' all linux/synclink.h conflict!
234
'm' 00-19 drivers/message/fusion/mptctl.h conflict!
235
'm' 00 drivers/scsi/megaraid/megaraid_ioctl.h conflict!
236
'm' 00-1F net/irda/irmod.h conflict!
237
'n' 00-7F linux/ncp_fs.h and fs/ncpfs/ioctl.c
238
'n' 80-8F linux/nilfs2_fs.h NILFS2
239
'n' E0-FF linux/matroxfb.h matroxfb
240
'o' 00-1F fs/ocfs2/ocfs2_fs.h OCFS2
241
'o' 00-03 mtd/ubi-user.h conflict! (OCFS2 and UBI overlaps)
242
'o' 40-41 mtd/ubi-user.h UBI
243
'o' 01-A1 linux/dvb/*.h DVB
244
'p' 00-0F linux/phantom.h conflict! (OpenHaptics needs this)
245
'p' 00-1F linux/rtc.h conflict!
246
'p' 00-3F linux/mc146818rtc.h conflict!
247
'p' 40-7F linux/nvram.h
248
'p' 80-9F linux/ppdev.h user-space parport
249
<mailto:tim@cyberelk.net>
250
'p' A1-A5 linux/pps.h LinuxPPS
251
<mailto:giometti@linux.it>
252
'q' 00-1F linux/serio.h
253
'q' 80-FF linux/telephony.h Internet PhoneJACK, Internet LineJACK
254
linux/ixjuser.h <http://web.archive.org/web/*/http://www.quicknet.net>
255
'r' 00-1F linux/msdos_fs.h and fs/fat/dir.c
257
't' 00-7F linux/if_ppp.h
258
't' 80-8F linux/isdn_ppp.h
259
't' 90 linux/toshiba.h
260
'u' 00-1F linux/smb_fs.h gone
261
'u' 20-3F linux/uvcvideo.h USB video class host driver
262
'v' 00-1F linux/ext2_fs.h conflict!
263
'v' 00-1F linux/fs.h conflict!
264
'v' 00-0F linux/sonypi.h conflict!
265
'v' C0-DF media/pwc-ioctl.h conflict!
266
'v' C0-FF linux/meye.h conflict!
267
'v' D0-DF drivers/media/video/cpia2/cpia2dev.h conflict!
268
'w' all CERN SCI driver
269
'y' 00-1F packet based user level communications
270
<mailto:zapman@interlan.net>
271
'z' 00-3F CAN bus card conflict!
272
<mailto:hdstich@connectu.ulm.circular.de>
273
'z' 40-7F CAN bus card conflict!
275
'z' 10-4F drivers/s390/crypto/zcrypt_api.h conflict!
276
'|' 00-7F linux/media.h
277
0x80 00-1F linux/fb.h
278
0x89 00-06 arch/x86/include/asm/sockios.h
279
0x89 0B-DF linux/sockios.h
280
0x89 E0-EF linux/sockios.h SIOCPROTOPRIVATE range
281
0x89 E0-EF linux/dn.h PROTOPRIVATE range
282
0x89 F0-FF linux/sockios.h SIOCDEVPRIVATE range
283
0x8B all linux/wireless.h
284
0x8C 00-3F WiNRADiO driver
285
<http://www.winradio.com.au/>
286
0x90 00 drivers/cdrom/sbpcd.h
287
0x92 00-0F drivers/usb/mon/mon_bin.c
288
0x93 60-7F linux/auto_fs.h
289
0x94 all fs/btrfs/ioctl.h
290
0x97 00-7F fs/ceph/ioctl.h Ceph file system
291
0x99 00-0F 537-Addinboard driver
292
<mailto:buk@buks.ipn.de>
293
0xA0 all linux/sdp/sdp.h Industrial Device Project
294
<mailto:kenji@bitgate.com>
295
0xA2 00-0F arch/tile/include/asm/hardwall.h
296
0xA3 80-8F Port ACL in development:
297
<mailto:tlewis@mindspring.com>
298
0xA3 90-9F linux/dtlk.h
299
0xAB 00-1F linux/nbd.h
300
0xAC 00-1F linux/raw.h
301
0xAD 00 Netfilter device in development:
302
<mailto:rusty@rustcorp.com.au>
303
0xAE all linux/kvm.h Kernel-based Virtual Machine
304
<mailto:kvm@vger.kernel.org>
305
0xAF 00-1F linux/fsl_hypervisor.h Freescale hypervisor
306
0xB0 all RATIO devices in development:
307
<mailto:vgo@ratio.de>
308
0xB1 00-1F PPPoX <mailto:mostrows@styx.uwaterloo.ca>
309
0xB3 00 linux/mmc/ioctl.h
310
0xC0 00-0F linux/usb/iowarrior.h
311
0xCB 00-1F CBM serial IEC bus in development:
312
<mailto:michael.klein@puffin.lb.shuttle.de>
313
0xCD 01 linux/reiserfs_fs.h
314
0xCF 02 fs/cifs/ioctl.c
315
0xDB 00-0F drivers/char/mwave/mwavepub.h
316
0xDD 00-3F ZFCP device driver see drivers/s390/scsi/
317
<mailto:aherrman@de.ibm.com>
318
0xF3 00-3F drivers/usb/misc/sisusbvga/sisusb.h sisfb (in development)
319
<mailto:thomas@winischhofer.net>
320
0xF4 00-1F video/mbxfb.h mbxfb
322
0xF6 all LTTng Linux Trace Toolkit Next Generation
323
<mailto:mathieu.desnoyers@efficios.com>
324
0xFD all linux/dm-ioctl.h