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Documentation / ioctl / ioctl-number.txt


Based on kernel version 4.16.1. Page generated on 2018-04-09 11:53 EST.

1	Ioctl Numbers
2	19 October 1999
3	Michael Elizabeth Chastain
4	<mec@shout.net>
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 <mec@shout.net> 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/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/.
62	
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!
69	0x02	all	linux/fd.h
70	0x03	all	linux/hdreg.h
71	0x04	D2-DC	linux/umsdos_fs.h	Dead since 2.6.11, but don't reuse these.
72	0x06	all	linux/lp.h
73	0x09	all	linux/raid/md_u.h
74	0x10	00-0F	drivers/char/s390/vmcp.h
75	0x10	10-1F	arch/s390/include/uapi/sclp_ctl.h
76	0x10	20-2F	arch/s390/include/uapi/asm/hypfs.h
77	0x12	all	linux/fs.h
78			linux/blkpg.h
79	0x1b	all	InfiniBand Subsystem	<http://infiniband.sourceforge.net/>
80	0x20	all	drivers/cdrom/cm206.h
81	0x22	all	scsi/sg.h
82	'#'	00-3F	IEEE 1394 Subsystem	Block for the entire subsystem
83	'$'	00-0F	linux/perf_counter.h, linux/perf_event.h
84	'%'	00-0F	include/uapi/linux/stm.h
85						System Trace Module subsystem
86						<mailto:alexander.shishkin@linux.intel.com>
87	'&'	00-07	drivers/firewire/nosy-user.h
88	'1'	00-1F	<linux/timepps.h>	PPS kit from Ulrich Windl
89						<ftp://ftp.de.kernel.org/pub/linux/daemons/ntp/PPS/>
90	'2'	01-04	linux/i2o.h
91	'3'	00-0F	drivers/s390/char/raw3270.h	conflict!
92	'3'	00-1F	linux/suspend_ioctls.h	conflict!
93			and kernel/power/user.c
94	'8'	all				SNP8023 advanced NIC card
95						<mailto:mcr@solidum.com>
96	';'	64-7F	linux/vfio.h
97	'@'	00-0F	linux/radeonfb.h	conflict!
98	'@'	00-0F	drivers/video/aty/aty128fb.c	conflict!
99	'A'	00-1F	linux/apm_bios.h	conflict!
100	'A'	00-0F	linux/agpgart.h		conflict!
101			and drivers/char/agp/compat_ioctl.h
102	'A'	00-7F	sound/asound.h		conflict!
103	'B'	00-1F	linux/cciss_ioctl.h	conflict!
104	'B'	00-0F	include/linux/pmu.h	conflict!
105	'B'	C0-FF				advanced bbus
106						<mailto:maassen@uni-freiburg.de>
107	'C'	all	linux/soundcard.h	conflict!
108	'C'	01-2F	linux/capi.h		conflict!
109	'C'	F0-FF	drivers/net/wan/cosa.h	conflict!
110	'D'	all	arch/s390/include/asm/dasd.h
111	'D'	40-5F	drivers/scsi/dpt/dtpi_ioctl.h
112	'D'	05	drivers/scsi/pmcraid.h
113	'E'	all	linux/input.h		conflict!
114	'E'	00-0F	xen/evtchn.h		conflict!
115	'F'	all	linux/fb.h		conflict!
116	'F'	01-02	drivers/scsi/pmcraid.h	conflict!
117	'F'	20	drivers/video/fsl-diu-fb.h	conflict!
118	'F'	20	drivers/video/intelfb/intelfb.h	conflict!
119	'F'	20	linux/ivtvfb.h		conflict!
120	'F'	20	linux/matroxfb.h	conflict!
121	'F'	20	drivers/video/aty/atyfb_base.c	conflict!
122	'F'	00-0F	video/da8xx-fb.h	conflict!
123	'F'	80-8F	linux/arcfb.h		conflict!
124	'F'	DD	video/sstfb.h		conflict!
125	'G'	00-3F	drivers/misc/sgi-gru/grulib.h	conflict!
126	'G'	00-0F	linux/gigaset_dev.h	conflict!
127	'H'	00-7F	linux/hiddev.h		conflict!
128	'H'	00-0F	linux/hidraw.h		conflict!
129	'H'	01	linux/mei.h		conflict!
130	'H'	02	linux/mei.h		conflict!
131	'H'	03	linux/mei.h		conflict!
132	'H'	00-0F	sound/asound.h		conflict!
133	'H'	20-40	sound/asound_fm.h	conflict!
134	'H'	80-8F	sound/sfnt_info.h	conflict!
135	'H'	10-8F	sound/emu10k1.h		conflict!
136	'H'	10-1F	sound/sb16_csp.h	conflict!
137	'H'	10-1F	sound/hda_hwdep.h	conflict!
138	'H'	40-4F	sound/hdspm.h		conflict!
139	'H'	40-4F	sound/hdsp.h		conflict!
140	'H'	90	sound/usb/usx2y/usb_stream.h
141	'H'	A0	uapi/linux/usb/cdc-wdm.h
142	'H'	C0-F0	net/bluetooth/hci.h	conflict!
143	'H'	C0-DF	net/bluetooth/hidp/hidp.h	conflict!
144	'H'	C0-DF	net/bluetooth/cmtp/cmtp.h	conflict!
145	'H'	C0-DF	net/bluetooth/bnep/bnep.h	conflict!
146	'H'	F1	linux/hid-roccat.h	<mailto:erazor_de@users.sourceforge.net>
147	'H'	F8-FA	sound/firewire.h
148	'I'	all	linux/isdn.h		conflict!
149	'I'	00-0F	drivers/isdn/divert/isdn_divert.h	conflict!
150	'I'	40-4F	linux/mISDNif.h		conflict!
151	'J'	00-1F	drivers/scsi/gdth_ioctl.h
152	'K'	all	linux/kd.h
153	'L'	00-1F	linux/loop.h		conflict!
154	'L'	10-1F	drivers/scsi/mpt2sas/mpt2sas_ctl.h	conflict!
155	'L'	20-2F	linux/lightnvm.h
156	'L'	E0-FF	linux/ppdd.h		encrypted disk device driver
157						<http://linux01.gwdg.de/~alatham/ppdd.html>
158	'M'	all	linux/soundcard.h	conflict!
159	'M'	01-16	mtd/mtd-abi.h		conflict!
160			and drivers/mtd/mtdchar.c
161	'M'	01-03	drivers/scsi/megaraid/megaraid_sas.h
162	'M'	00-0F	drivers/video/fsl-diu-fb.h	conflict!
163	'N'	00-1F	drivers/usb/scanner.h
164	'N'	40-7F	drivers/block/nvme.c
165	'O'     00-06   mtd/ubi-user.h		UBI
166	'P'	all	linux/soundcard.h	conflict!
167	'P'	60-6F	sound/sscape_ioctl.h	conflict!
168	'P'	00-0F	drivers/usb/class/usblp.c	conflict!
169	'Q'	all	linux/soundcard.h
170	'R'	00-1F	linux/random.h		conflict!
171	'R'	01	linux/rfkill.h		conflict!
172	'R'	C0-DF	net/bluetooth/rfcomm.h
173	'S'	all	linux/cdrom.h		conflict!
174	'S'	80-81	scsi/scsi_ioctl.h	conflict!
175	'S'	82-FF	scsi/scsi.h		conflict!
176	'S'	00-7F	sound/asequencer.h	conflict!
177	'T'	all	linux/soundcard.h	conflict!
178	'T'	00-AF	sound/asound.h		conflict!
179	'T'	all	arch/x86/include/asm/ioctls.h	conflict!
180	'T'	C0-DF	linux/if_tun.h		conflict!
181	'U'	all	sound/asound.h		conflict!
182	'U'	00-CF	linux/uinput.h		conflict!
183	'U'	00-EF	linux/usbdevice_fs.h
184	'U'	C0-CF	drivers/bluetooth/hci_uart.h
185	'V'	all	linux/vt.h		conflict!
186	'V'	all	linux/videodev2.h	conflict!
187	'V'	C0	linux/ivtvfb.h		conflict!
188	'V'	C0	linux/ivtv.h		conflict!
189	'V'	C0	media/davinci/vpfe_capture.h	conflict!
190	'V'	C0	media/si4713.h		conflict!
191	'W'	00-1F	linux/watchdog.h	conflict!
192	'W'	00-1F	linux/wanrouter.h	conflict!		(pre 3.9)
193	'W'	00-3F	sound/asound.h		conflict!
194	'W'	40-5F   drivers/pci/switch/switchtec.c
195	'X'	all	fs/xfs/xfs_fs.h		conflict!
196			and fs/xfs/linux-2.6/xfs_ioctl32.h
197			and include/linux/falloc.h
198			and linux/fs.h
199	'X'	all	fs/ocfs2/ocfs_fs.h	conflict!
200	'X'	01	linux/pktcdvd.h		conflict!
201	'Y'	all	linux/cyclades.h
202	'Z'	14-15	drivers/message/fusion/mptctl.h
203	'['	00-07	linux/usb/tmc.h		USB Test and Measurement Devices
204						<mailto:gregkh@linuxfoundation.org>
205	'a'	all	linux/atm*.h, linux/sonet.h	ATM on linux
206						<http://lrcwww.epfl.ch/>
207	'a'	00-0F	drivers/crypto/qat/qat_common/adf_cfg_common.h	conflict! qat driver
208	'b'	00-FF				conflict! bit3 vme host bridge
209						<mailto:natalia@nikhefk.nikhef.nl>
210	'c'	all	linux/cm4000_cs.h	conflict!
211	'c'	00-7F	linux/comstats.h	conflict!
212	'c'	00-7F	linux/coda.h		conflict!
213	'c'	00-1F	linux/chio.h		conflict!
214	'c'	80-9F	arch/s390/include/asm/chsc.h	conflict!
215	'c'	A0-AF   arch/x86/include/asm/msr.h	conflict!
216	'd'	00-FF	linux/char/drm/drm.h	conflict!
217	'd'	02-40	pcmcia/ds.h		conflict!
218	'd'	F0-FF	linux/digi1.h
219	'e'	all	linux/digi1.h		conflict!
220	'e'	00-1F	drivers/net/irda/irtty-sir.h	conflict!
221	'f'	00-1F	linux/ext2_fs.h		conflict!
222	'f'	00-1F	linux/ext3_fs.h		conflict!
223	'f'	00-0F	fs/jfs/jfs_dinode.h	conflict!
224	'f'	00-0F	fs/ext4/ext4.h		conflict!
225	'f'	00-0F	linux/fs.h		conflict!
226	'f'	00-0F	fs/ocfs2/ocfs2_fs.h	conflict!
227	'g'	00-0F	linux/usb/gadgetfs.h
228	'g'	20-2F	linux/usb/g_printer.h
229	'h'	00-7F				conflict! Charon filesystem
230						<mailto:zapman@interlan.net>
231	'h'	00-1F	linux/hpet.h		conflict!
232	'h'	80-8F	fs/hfsplus/ioctl.c
233	'i'	00-3F	linux/i2o-dev.h		conflict!
234	'i'	0B-1F	linux/ipmi.h		conflict!
235	'i'	80-8F	linux/i8k.h
236	'j'	00-3F	linux/joystick.h
237	'k'	00-0F	linux/spi/spidev.h	conflict!
238	'k'	00-05	video/kyro.h		conflict!
239	'k'	10-17	linux/hsi/hsi_char.h	HSI character device
240	'l'	00-3F	linux/tcfs_fs.h		transparent cryptographic file system
241						<http://web.archive.org/web/*/http://mikonos.dia.unisa.it/tcfs>
242	'l'	40-7F	linux/udf_fs_i.h	in development:
243						<http://sourceforge.net/projects/linux-udf/>
244	'm'	00-09	linux/mmtimer.h		conflict!
245	'm'	all	linux/mtio.h		conflict!
246	'm'	all	linux/soundcard.h	conflict!
247	'm'	all	linux/synclink.h	conflict!
248	'm'	00-19	drivers/message/fusion/mptctl.h	conflict!
249	'm'	00	drivers/scsi/megaraid/megaraid_ioctl.h	conflict!
250	'm'	00-1F	net/irda/irmod.h	conflict!
251	'n'	00-7F	linux/ncp_fs.h and fs/ncpfs/ioctl.c
252	'n'	80-8F	uapi/linux/nilfs2_api.h	NILFS2
253	'n'	E0-FF	linux/matroxfb.h	matroxfb
254	'o'	00-1F	fs/ocfs2/ocfs2_fs.h	OCFS2
255	'o'     00-03   mtd/ubi-user.h		conflict! (OCFS2 and UBI overlaps)
256	'o'     40-41   mtd/ubi-user.h		UBI
257	'o'     01-A1   linux/dvb/*.h		DVB
258	'p'	00-0F	linux/phantom.h		conflict! (OpenHaptics needs this)
259	'p'	00-1F	linux/rtc.h		conflict!
260	'p'	00-3F	linux/mc146818rtc.h	conflict!
261	'p'	40-7F	linux/nvram.h
262	'p'	80-9F	linux/ppdev.h		user-space parport
263						<mailto:tim@cyberelk.net>
264	'p'	A1-A5	linux/pps.h		LinuxPPS
265						<mailto:giometti@linux.it>
266	'q'	00-1F	linux/serio.h
267	'q'	80-FF	linux/telephony.h	Internet PhoneJACK, Internet LineJACK
268			linux/ixjuser.h		<http://web.archive.org/web/*/http://www.quicknet.net>
269	'r'	00-1F	linux/msdos_fs.h and fs/fat/dir.c
270	's'	all	linux/cdk.h
271	't'	00-7F	linux/ppp-ioctl.h
272	't'	80-8F	linux/isdn_ppp.h
273	't'	90-91	linux/toshiba.h		toshiba and toshiba_acpi SMM
274	'u'	00-1F	linux/smb_fs.h		gone
275	'u'	20-3F	linux/uvcvideo.h	USB video class host driver
276	'v'	00-1F	linux/ext2_fs.h		conflict!
277	'v'	00-1F	linux/fs.h		conflict!
278	'v'	00-0F	linux/sonypi.h		conflict!
279	'v'	C0-FF	linux/meye.h		conflict!
280	'w'	all				CERN SCI driver
281	'y'	00-1F				packet based user level communications
282						<mailto:zapman@interlan.net>
283	'z'	00-3F				CAN bus card	conflict!
284						<mailto:hdstich@connectu.ulm.circular.de>
285	'z'	40-7F				CAN bus card	conflict!
286						<mailto:oe@port.de>
287	'z'	10-4F	drivers/s390/crypto/zcrypt_api.h	conflict!
288	'|'	00-7F	linux/media.h
289	0x80	00-1F	linux/fb.h
290	0x89	00-06	arch/x86/include/asm/sockios.h
291	0x89	0B-DF	linux/sockios.h
292	0x89	E0-EF	linux/sockios.h		SIOCPROTOPRIVATE range
293	0x89	E0-EF	linux/dn.h		PROTOPRIVATE range
294	0x89	F0-FF	linux/sockios.h		SIOCDEVPRIVATE range
295	0x8B	all	linux/wireless.h
296	0x8C	00-3F				WiNRADiO driver
297						<http://www.winradio.com.au/>
298	0x90	00	drivers/cdrom/sbpcd.h
299	0x92	00-0F	drivers/usb/mon/mon_bin.c
300	0x93	60-7F	linux/auto_fs.h
301	0x94	all	fs/btrfs/ioctl.h
302	0x97	00-7F	fs/ceph/ioctl.h		Ceph file system
303	0x99	00-0F				537-Addinboard driver
304						<mailto:buk@buks.ipn.de>
305	0xA0	all	linux/sdp/sdp.h		Industrial Device Project
306						<mailto:kenji@bitgate.com>
307	0xA1	0	linux/vtpm_proxy.h	TPM Emulator Proxy Driver
308	0xA2	00-0F	arch/tile/include/asm/hardwall.h
309	0xA3	80-8F	Port ACL		in development:
310						<mailto:tlewis@mindspring.com>
311	0xA3	90-9F	linux/dtlk.h
312	0xA4	00-1F	uapi/linux/tee.h	Generic TEE subsystem
313	0xAA	00-3F	linux/uapi/linux/userfaultfd.h
314	0xAB	00-1F	linux/nbd.h
315	0xAC	00-1F	linux/raw.h
316	0xAD	00	Netfilter device	in development:
317						<mailto:rusty@rustcorp.com.au>
318	0xAE	all	linux/kvm.h		Kernel-based Virtual Machine
319						<mailto:kvm@vger.kernel.org>
320	0xAF	00-1F	linux/fsl_hypervisor.h	Freescale hypervisor
321	0xB0	all	RATIO devices		in development:
322						<mailto:vgo@ratio.de>
323	0xB1	00-1F	PPPoX			<mailto:mostrows@styx.uwaterloo.ca>
324	0xB3	00	linux/mmc/ioctl.h
325	0xB4	00-0F	linux/gpio.h		<mailto:linux-gpio@vger.kernel.org>
326	0xB5	00-0F	uapi/linux/rpmsg.h	<mailto:linux-remoteproc@vger.kernel.org>
327	0xC0	00-0F	linux/usb/iowarrior.h
328	0xCA	00-0F	uapi/misc/cxl.h
329	0xCA	10-2F	uapi/misc/ocxl.h
330	0xCA	80-BF	uapi/scsi/cxlflash_ioctl.h
331	0xCB	00-1F	CBM serial IEC bus	in development:
332						<mailto:michael.klein@puffin.lb.shuttle.de>
333	0xCD	01	linux/reiserfs_fs.h
334	0xCF	02	fs/cifs/ioctl.c
335	0xDB	00-0F	drivers/char/mwave/mwavepub.h
336	0xDD	00-3F	ZFCP device driver	see drivers/s390/scsi/
337						<mailto:aherrman@de.ibm.com>
338	0xE5	00-3F	linux/fuse.h
339	0xEC	00-01	drivers/platform/chrome/cros_ec_dev.h	ChromeOS EC driver
340	0xF3	00-3F	drivers/usb/misc/sisusbvga/sisusb.h	sisfb (in development)
341						<mailto:thomas@winischhofer.net>
342	0xF4	00-1F	video/mbxfb.h		mbxfb
343						<mailto:raph@8d.com>
344	0xF6	all	LTTng			Linux Trace Toolkit Next Generation
345						<mailto:mathieu.desnoyers@efficios.com>
346	0xFD	all	linux/dm-ioctl.h
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