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-rw-r--r--Documentation/userspace-api/ioctl/cdrom.rst1242
-rw-r--r--Documentation/userspace-api/ioctl/hdio.rst547
-rw-r--r--Documentation/userspace-api/ioctl/index.rst15
-rw-r--r--Documentation/userspace-api/ioctl/ioctl-decoding.rst31
-rw-r--r--Documentation/userspace-api/ioctl/ioctl-number.rst381
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diff --git a/Documentation/userspace-api/ioctl/cdrom.rst b/Documentation/userspace-api/ioctl/cdrom.rst
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+============================
+Summary of CDROM ioctl calls
+============================
+
+- Edward A. Falk <efalk@google.com>
+
+November, 2004
+
+This document attempts to describe the ioctl(2) calls supported by
+the CDROM layer. These are by-and-large implemented (as of Linux 2.6)
+in drivers/cdrom/cdrom.c and drivers/block/scsi_ioctl.c
+
+ioctl values are listed in <linux/cdrom.h>. As of this writing, they
+are as follows:
+
+ ======================== ===============================================
+ CDROMPAUSE Pause Audio Operation
+ CDROMRESUME Resume paused Audio Operation
+ CDROMPLAYMSF Play Audio MSF (struct cdrom_msf)
+ CDROMPLAYTRKIND Play Audio Track/index (struct cdrom_ti)
+ CDROMREADTOCHDR Read TOC header (struct cdrom_tochdr)
+ CDROMREADTOCENTRY Read TOC entry (struct cdrom_tocentry)
+ CDROMSTOP Stop the cdrom drive
+ CDROMSTART Start the cdrom drive
+ CDROMEJECT Ejects the cdrom media
+ CDROMVOLCTRL Control output volume (struct cdrom_volctrl)
+ CDROMSUBCHNL Read subchannel data (struct cdrom_subchnl)
+ CDROMREADMODE2 Read CDROM mode 2 data (2336 Bytes)
+ (struct cdrom_read)
+ CDROMREADMODE1 Read CDROM mode 1 data (2048 Bytes)
+ (struct cdrom_read)
+ CDROMREADAUDIO (struct cdrom_read_audio)
+ CDROMEJECT_SW enable(1)/disable(0) auto-ejecting
+ CDROMMULTISESSION Obtain the start-of-last-session
+ address of multi session disks
+ (struct cdrom_multisession)
+ CDROM_GET_MCN Obtain the "Universal Product Code"
+ if available (struct cdrom_mcn)
+ CDROM_GET_UPC Deprecated, use CDROM_GET_MCN instead.
+ CDROMRESET hard-reset the drive
+ CDROMVOLREAD Get the drive's volume setting
+ (struct cdrom_volctrl)
+ CDROMREADRAW read data in raw mode (2352 Bytes)
+ (struct cdrom_read)
+ CDROMREADCOOKED read data in cooked mode
+ CDROMSEEK seek msf address
+ CDROMPLAYBLK scsi-cd only, (struct cdrom_blk)
+ CDROMREADALL read all 2646 bytes
+ CDROMGETSPINDOWN return 4-bit spindown value
+ CDROMSETSPINDOWN set 4-bit spindown value
+ CDROMCLOSETRAY pendant of CDROMEJECT
+ CDROM_SET_OPTIONS Set behavior options
+ CDROM_CLEAR_OPTIONS Clear behavior options
+ CDROM_SELECT_SPEED Set the CD-ROM speed
+ CDROM_SELECT_DISC Select disc (for juke-boxes)
+ CDROM_MEDIA_CHANGED Check is media changed
+ CDROM_TIMED_MEDIA_CHANGE Check if media changed
+ since given time
+ (struct cdrom_timed_media_change_info)
+ CDROM_DRIVE_STATUS Get tray position, etc.
+ CDROM_DISC_STATUS Get disc type, etc.
+ CDROM_CHANGER_NSLOTS Get number of slots
+ CDROM_LOCKDOOR lock or unlock door
+ CDROM_DEBUG Turn debug messages on/off
+ CDROM_GET_CAPABILITY get capabilities
+ CDROMAUDIOBUFSIZ set the audio buffer size
+ DVD_READ_STRUCT Read structure
+ DVD_WRITE_STRUCT Write structure
+ DVD_AUTH Authentication
+ CDROM_SEND_PACKET send a packet to the drive
+ CDROM_NEXT_WRITABLE get next writable block
+ CDROM_LAST_WRITTEN get last block written on disc
+ ======================== ===============================================
+
+
+The information that follows was determined from reading kernel source
+code. It is likely that some corrections will be made over time.
+
+------------------------------------------------------------------------------
+
+General:
+
+ Unless otherwise specified, all ioctl calls return 0 on success
+ and -1 with errno set to an appropriate value on error. (Some
+ ioctls return non-negative data values.)
+
+ Unless otherwise specified, all ioctl calls return -1 and set
+ errno to EFAULT on a failed attempt to copy data to or from user
+ address space.
+
+ Individual drivers may return error codes not listed here.
+
+ Unless otherwise specified, all data structures and constants
+ are defined in <linux/cdrom.h>
+
+------------------------------------------------------------------------------
+
+
+CDROMPAUSE
+ Pause Audio Operation
+
+
+ usage::
+
+ ioctl(fd, CDROMPAUSE, 0);
+
+
+ inputs:
+ none
+
+
+ outputs:
+ none
+
+
+ error return:
+ - ENOSYS cd drive not audio-capable.
+
+
+CDROMRESUME
+ Resume paused Audio Operation
+
+
+ usage::
+
+ ioctl(fd, CDROMRESUME, 0);
+
+
+ inputs:
+ none
+
+
+ outputs:
+ none
+
+
+ error return:
+ - ENOSYS cd drive not audio-capable.
+
+
+CDROMPLAYMSF
+ Play Audio MSF
+
+ (struct cdrom_msf)
+
+
+ usage::
+
+ struct cdrom_msf msf;
+
+ ioctl(fd, CDROMPLAYMSF, &msf);
+
+ inputs:
+ cdrom_msf structure, describing a segment of music to play
+
+
+ outputs:
+ none
+
+
+ error return:
+ - ENOSYS cd drive not audio-capable.
+
+ notes:
+ - MSF stands for minutes-seconds-frames
+ - LBA stands for logical block address
+ - Segment is described as start and end times, where each time
+ is described as minutes:seconds:frames.
+ A frame is 1/75 of a second.
+
+
+CDROMPLAYTRKIND
+ Play Audio Track/index
+
+ (struct cdrom_ti)
+
+
+ usage::
+
+ struct cdrom_ti ti;
+
+ ioctl(fd, CDROMPLAYTRKIND, &ti);
+
+ inputs:
+ cdrom_ti structure, describing a segment of music to play
+
+
+ outputs:
+ none
+
+
+ error return:
+ - ENOSYS cd drive not audio-capable.
+
+ notes:
+ - Segment is described as start and end times, where each time
+ is described as a track and an index.
+
+
+
+CDROMREADTOCHDR
+ Read TOC header
+
+ (struct cdrom_tochdr)
+
+
+ usage::
+
+ cdrom_tochdr header;
+
+ ioctl(fd, CDROMREADTOCHDR, &header);
+
+ inputs:
+ cdrom_tochdr structure
+
+
+ outputs:
+ cdrom_tochdr structure
+
+
+ error return:
+ - ENOSYS cd drive not audio-capable.
+
+
+
+CDROMREADTOCENTRY
+ Read TOC entry
+
+ (struct cdrom_tocentry)
+
+
+ usage::
+
+ struct cdrom_tocentry entry;
+
+ ioctl(fd, CDROMREADTOCENTRY, &entry);
+
+ inputs:
+ cdrom_tocentry structure
+
+
+ outputs:
+ cdrom_tocentry structure
+
+
+ error return:
+ - ENOSYS cd drive not audio-capable.
+ - EINVAL entry.cdte_format not CDROM_MSF or CDROM_LBA
+ - EINVAL requested track out of bounds
+ - EIO I/O error reading TOC
+
+ notes:
+ - TOC stands for Table Of Contents
+ - MSF stands for minutes-seconds-frames
+ - LBA stands for logical block address
+
+
+
+CDROMSTOP
+ Stop the cdrom drive
+
+
+ usage::
+
+ ioctl(fd, CDROMSTOP, 0);
+
+
+ inputs:
+ none
+
+
+ outputs:
+ none
+
+
+ error return:
+ - ENOSYS cd drive not audio-capable.
+
+ notes:
+ - Exact interpretation of this ioctl depends on the device,
+ but most seem to spin the drive down.
+
+
+CDROMSTART
+ Start the cdrom drive
+
+
+ usage::
+
+ ioctl(fd, CDROMSTART, 0);
+
+
+ inputs:
+ none
+
+
+ outputs:
+ none
+
+
+ error return:
+ - ENOSYS cd drive not audio-capable.
+
+ notes:
+ - Exact interpretation of this ioctl depends on the device,
+ but most seem to spin the drive up and/or close the tray.
+ Other devices ignore the ioctl completely.
+
+
+CDROMEJECT
+ - Ejects the cdrom media
+
+
+ usage::
+
+ ioctl(fd, CDROMEJECT, 0);
+
+
+ inputs:
+ none
+
+
+ outputs:
+ none
+
+
+ error returns:
+ - ENOSYS cd drive not capable of ejecting
+ - EBUSY other processes are accessing drive, or door is locked
+
+ notes:
+ - See CDROM_LOCKDOOR, below.
+
+
+
+
+CDROMCLOSETRAY
+ pendant of CDROMEJECT
+
+
+ usage::
+
+ ioctl(fd, CDROMCLOSETRAY, 0);
+
+
+ inputs:
+ none
+
+
+ outputs:
+ none
+
+
+ error returns:
+ - ENOSYS cd drive not capable of closing the tray
+ - EBUSY other processes are accessing drive, or door is locked
+
+ notes:
+ - See CDROM_LOCKDOOR, below.
+
+
+
+
+CDROMVOLCTRL
+ Control output volume (struct cdrom_volctrl)
+
+
+ usage::
+
+ struct cdrom_volctrl volume;
+
+ ioctl(fd, CDROMVOLCTRL, &volume);
+
+ inputs:
+ cdrom_volctrl structure containing volumes for up to 4
+ channels.
+
+ outputs:
+ none
+
+
+ error return:
+ - ENOSYS cd drive not audio-capable.
+
+
+
+CDROMVOLREAD
+ Get the drive's volume setting
+
+ (struct cdrom_volctrl)
+
+
+ usage::
+
+ struct cdrom_volctrl volume;
+
+ ioctl(fd, CDROMVOLREAD, &volume);
+
+ inputs:
+ none
+
+
+ outputs:
+ The current volume settings.
+
+
+ error return:
+ - ENOSYS cd drive not audio-capable.
+
+
+
+CDROMSUBCHNL
+ Read subchannel data
+
+ (struct cdrom_subchnl)
+
+
+ usage::
+
+ struct cdrom_subchnl q;
+
+ ioctl(fd, CDROMSUBCHNL, &q);
+
+ inputs:
+ cdrom_subchnl structure
+
+
+ outputs:
+ cdrom_subchnl structure
+
+
+ error return:
+ - ENOSYS cd drive not audio-capable.
+ - EINVAL format not CDROM_MSF or CDROM_LBA
+
+ notes:
+ - Format is converted to CDROM_MSF or CDROM_LBA
+ as per user request on return
+
+
+
+CDROMREADRAW
+ read data in raw mode (2352 Bytes)
+
+ (struct cdrom_read)
+
+ usage::
+
+ union {
+
+ struct cdrom_msf msf; /* input */
+ char buffer[CD_FRAMESIZE_RAW]; /* return */
+ } arg;
+ ioctl(fd, CDROMREADRAW, &arg);
+
+ inputs:
+ cdrom_msf structure indicating an address to read.
+
+ Only the start values are significant.
+
+ outputs:
+ Data written to address provided by user.
+
+
+ error return:
+ - EINVAL address less than 0, or msf less than 0:2:0
+ - ENOMEM out of memory
+
+ notes:
+ - As of 2.6.8.1, comments in <linux/cdrom.h> indicate that this
+ ioctl accepts a cdrom_read structure, but actual source code
+ reads a cdrom_msf structure and writes a buffer of data to
+ the same address.
+
+ - MSF values are converted to LBA values via this formula::
+
+ lba = (((m * CD_SECS) + s) * CD_FRAMES + f) - CD_MSF_OFFSET;
+
+
+
+
+CDROMREADMODE1
+ Read CDROM mode 1 data (2048 Bytes)
+
+ (struct cdrom_read)
+
+ notes:
+ Identical to CDROMREADRAW except that block size is
+ CD_FRAMESIZE (2048) bytes
+
+
+
+CDROMREADMODE2
+ Read CDROM mode 2 data (2336 Bytes)
+
+ (struct cdrom_read)
+
+ notes:
+ Identical to CDROMREADRAW except that block size is
+ CD_FRAMESIZE_RAW0 (2336) bytes
+
+
+
+CDROMREADAUDIO
+ (struct cdrom_read_audio)
+
+ usage::
+
+ struct cdrom_read_audio ra;
+
+ ioctl(fd, CDROMREADAUDIO, &ra);
+
+ inputs:
+ cdrom_read_audio structure containing read start
+ point and length
+
+ outputs:
+ audio data, returned to buffer indicated by ra
+
+
+ error return:
+ - EINVAL format not CDROM_MSF or CDROM_LBA
+ - EINVAL nframes not in range [1 75]
+ - ENXIO drive has no queue (probably means invalid fd)
+ - ENOMEM out of memory
+
+
+CDROMEJECT_SW
+ enable(1)/disable(0) auto-ejecting
+
+
+ usage::
+
+ int val;
+
+ ioctl(fd, CDROMEJECT_SW, val);
+
+ inputs:
+ Flag specifying auto-eject flag.
+
+
+ outputs:
+ none
+
+
+ error return:
+ - ENOSYS Drive is not capable of ejecting.
+ - EBUSY Door is locked
+
+
+
+
+CDROMMULTISESSION
+ Obtain the start-of-last-session address of multi session disks
+
+ (struct cdrom_multisession)
+
+ usage::
+
+ struct cdrom_multisession ms_info;
+
+ ioctl(fd, CDROMMULTISESSION, &ms_info);
+
+ inputs:
+ cdrom_multisession structure containing desired
+
+ format.
+
+ outputs:
+ cdrom_multisession structure is filled with last_session
+ information.
+
+ error return:
+ - EINVAL format not CDROM_MSF or CDROM_LBA
+
+
+CDROM_GET_MCN
+ Obtain the "Universal Product Code"
+ if available
+
+ (struct cdrom_mcn)
+
+
+ usage::
+
+ struct cdrom_mcn mcn;
+
+ ioctl(fd, CDROM_GET_MCN, &mcn);
+
+ inputs:
+ none
+
+
+ outputs:
+ Universal Product Code
+
+
+ error return:
+ - ENOSYS Drive is not capable of reading MCN data.
+
+ notes:
+ - Source code comments state::
+
+ The following function is implemented, although very few
+ audio discs give Universal Product Code information, which
+ should just be the Medium Catalog Number on the box. Note,
+ that the way the code is written on the CD is /not/ uniform
+ across all discs!
+
+
+
+
+CDROM_GET_UPC
+ CDROM_GET_MCN (deprecated)
+
+
+ Not implemented, as of 2.6.8.1
+
+
+
+CDROMRESET
+ hard-reset the drive
+
+
+ usage::
+
+ ioctl(fd, CDROMRESET, 0);
+
+
+ inputs:
+ none
+
+
+ outputs:
+ none
+
+
+ error return:
+ - EACCES Access denied: requires CAP_SYS_ADMIN
+ - ENOSYS Drive is not capable of resetting.
+
+
+
+
+CDROMREADCOOKED
+ read data in cooked mode
+
+
+ usage::
+
+ u8 buffer[CD_FRAMESIZE]
+
+ ioctl(fd, CDROMREADCOOKED, buffer);
+
+ inputs:
+ none
+
+
+ outputs:
+ 2048 bytes of data, "cooked" mode.
+
+
+ notes:
+ Not implemented on all drives.
+
+
+
+
+
+CDROMREADALL
+ read all 2646 bytes
+
+
+ Same as CDROMREADCOOKED, but reads 2646 bytes.
+
+
+
+CDROMSEEK
+ seek msf address
+
+
+ usage::
+
+ struct cdrom_msf msf;
+
+ ioctl(fd, CDROMSEEK, &msf);
+
+ inputs:
+ MSF address to seek to.
+
+
+ outputs:
+ none
+
+
+
+
+CDROMPLAYBLK
+ scsi-cd only
+
+ (struct cdrom_blk)
+
+
+ usage::
+
+ struct cdrom_blk blk;
+
+ ioctl(fd, CDROMPLAYBLK, &blk);
+
+ inputs:
+ Region to play
+
+
+ outputs:
+ none
+
+
+
+
+CDROMGETSPINDOWN
+ Obsolete, was ide-cd only
+
+
+ usage::
+
+ char spindown;
+
+ ioctl(fd, CDROMGETSPINDOWN, &spindown);
+
+ inputs:
+ none
+
+
+ outputs:
+ The value of the current 4-bit spindown value.
+
+
+
+
+
+CDROMSETSPINDOWN
+ Obsolete, was ide-cd only
+
+
+ usage::
+
+ char spindown
+
+ ioctl(fd, CDROMSETSPINDOWN, &spindown);
+
+ inputs:
+ 4-bit value used to control spindown (TODO: more detail here)
+
+
+ outputs:
+ none
+
+
+
+
+
+
+CDROM_SET_OPTIONS
+ Set behavior options
+
+
+ usage::
+
+ int options;
+
+ ioctl(fd, CDROM_SET_OPTIONS, options);
+
+ inputs:
+ New values for drive options. The logical 'or' of:
+
+ ============== ==================================
+ CDO_AUTO_CLOSE close tray on first open(2)
+ CDO_AUTO_EJECT open tray on last release
+ CDO_USE_FFLAGS use O_NONBLOCK information on open
+ CDO_LOCK lock tray on open files
+ CDO_CHECK_TYPE check type on open for data
+ ============== ==================================
+
+ outputs:
+ Returns the resulting options settings in the
+ ioctl return value. Returns -1 on error.
+
+ error return:
+ - ENOSYS selected option(s) not supported by drive.
+
+
+
+
+CDROM_CLEAR_OPTIONS
+ Clear behavior options
+
+
+ Same as CDROM_SET_OPTIONS, except that selected options are
+ turned off.
+
+
+
+CDROM_SELECT_SPEED
+ Set the CD-ROM speed
+
+
+ usage::
+
+ int speed;
+
+ ioctl(fd, CDROM_SELECT_SPEED, speed);
+
+ inputs:
+ New drive speed.
+
+
+ outputs:
+ none
+
+
+ error return:
+ - ENOSYS speed selection not supported by drive.
+
+
+
+CDROM_SELECT_DISC
+ Select disc (for juke-boxes)
+
+
+ usage::
+
+ int disk;
+
+ ioctl(fd, CDROM_SELECT_DISC, disk);
+
+ inputs:
+ Disk to load into drive.
+
+
+ outputs:
+ none
+
+
+ error return:
+ - EINVAL Disk number beyond capacity of drive
+
+
+
+CDROM_MEDIA_CHANGED
+ Check is media changed
+
+
+ usage::
+
+ int slot;
+
+ ioctl(fd, CDROM_MEDIA_CHANGED, slot);
+
+ inputs:
+ Slot number to be tested, always zero except for jukeboxes.
+
+ May also be special values CDSL_NONE or CDSL_CURRENT
+
+ outputs:
+ Ioctl return value is 0 or 1 depending on whether the media
+
+ has been changed, or -1 on error.
+
+ error returns:
+ - ENOSYS Drive can't detect media change
+ - EINVAL Slot number beyond capacity of drive
+ - ENOMEM Out of memory
+
+
+
+CDROM_DRIVE_STATUS
+ Get tray position, etc.
+
+
+ usage::
+
+ int slot;
+
+ ioctl(fd, CDROM_DRIVE_STATUS, slot);
+
+ inputs:
+ Slot number to be tested, always zero except for jukeboxes.
+
+ May also be special values CDSL_NONE or CDSL_CURRENT
+
+ outputs:
+ Ioctl return value will be one of the following values
+
+ from <linux/cdrom.h>:
+
+ =================== ==========================
+ CDS_NO_INFO Information not available.
+ CDS_NO_DISC
+ CDS_TRAY_OPEN
+ CDS_DRIVE_NOT_READY
+ CDS_DISC_OK
+ -1 error
+ =================== ==========================
+
+ error returns:
+ - ENOSYS Drive can't detect drive status
+ - EINVAL Slot number beyond capacity of drive
+ - ENOMEM Out of memory
+
+
+
+
+CDROM_DISC_STATUS
+ Get disc type, etc.
+
+
+ usage::
+
+ ioctl(fd, CDROM_DISC_STATUS, 0);
+
+
+ inputs:
+ none
+
+
+ outputs:
+ Ioctl return value will be one of the following values
+
+ from <linux/cdrom.h>:
+
+ - CDS_NO_INFO
+ - CDS_AUDIO
+ - CDS_MIXED
+ - CDS_XA_2_2
+ - CDS_XA_2_1
+ - CDS_DATA_1
+
+ error returns:
+ none at present
+
+ notes:
+ - Source code comments state::
+
+
+ Ok, this is where problems start. The current interface for
+ the CDROM_DISC_STATUS ioctl is flawed. It makes the false
+ assumption that CDs are all CDS_DATA_1 or all CDS_AUDIO, etc.
+ Unfortunately, while this is often the case, it is also
+ very common for CDs to have some tracks with data, and some
+ tracks with audio. Just because I feel like it, I declare
+ the following to be the best way to cope. If the CD has
+ ANY data tracks on it, it will be returned as a data CD.
+ If it has any XA tracks, I will return it as that. Now I
+ could simplify this interface by combining these returns with
+ the above, but this more clearly demonstrates the problem
+ with the current interface. Too bad this wasn't designed
+ to use bitmasks... -Erik
+
+ Well, now we have the option CDS_MIXED: a mixed-type CD.
+ User level programmers might feel the ioctl is not very
+ useful.
+ ---david
+
+
+
+
+CDROM_CHANGER_NSLOTS
+ Get number of slots
+
+
+ usage::
+
+ ioctl(fd, CDROM_CHANGER_NSLOTS, 0);
+
+
+ inputs:
+ none
+
+
+ outputs:
+ The ioctl return value will be the number of slots in a
+ CD changer. Typically 1 for non-multi-disk devices.
+
+ error returns:
+ none
+
+
+
+CDROM_LOCKDOOR
+ lock or unlock door
+
+
+ usage::
+
+ int lock;
+
+ ioctl(fd, CDROM_LOCKDOOR, lock);
+
+ inputs:
+ Door lock flag, 1=lock, 0=unlock
+
+
+ outputs:
+ none
+
+
+ error returns:
+ - EDRIVE_CANT_DO_THIS
+
+ Door lock function not supported.
+ - EBUSY
+
+ Attempt to unlock when multiple users
+ have the drive open and not CAP_SYS_ADMIN
+
+ notes:
+ As of 2.6.8.1, the lock flag is a global lock, meaning that
+ all CD drives will be locked or unlocked together. This is
+ probably a bug.
+
+ The EDRIVE_CANT_DO_THIS value is defined in <linux/cdrom.h>
+ and is currently (2.6.8.1) the same as EOPNOTSUPP
+
+
+
+CDROM_DEBUG
+ Turn debug messages on/off
+
+
+ usage::
+
+ int debug;
+
+ ioctl(fd, CDROM_DEBUG, debug);
+
+ inputs:
+ Cdrom debug flag, 0=disable, 1=enable
+
+
+ outputs:
+ The ioctl return value will be the new debug flag.
+
+
+ error return:
+ - EACCES Access denied: requires CAP_SYS_ADMIN
+
+
+
+CDROM_GET_CAPABILITY
+ get capabilities
+
+
+ usage::
+
+ ioctl(fd, CDROM_GET_CAPABILITY, 0);
+
+
+ inputs:
+ none
+
+
+ outputs:
+ The ioctl return value is the current device capability
+ flags. See CDC_CLOSE_TRAY, CDC_OPEN_TRAY, etc.
+
+
+
+CDROMAUDIOBUFSIZ
+ set the audio buffer size
+
+
+ usage::
+
+ int arg;
+
+ ioctl(fd, CDROMAUDIOBUFSIZ, val);
+
+ inputs:
+ New audio buffer size
+
+
+ outputs:
+ The ioctl return value is the new audio buffer size, or -1
+ on error.
+
+ error return:
+ - ENOSYS Not supported by this driver.
+
+ notes:
+ Not supported by all drivers.
+
+
+
+
+DVD_READ_STRUCT Read structure
+
+ usage::
+
+ dvd_struct s;
+
+ ioctl(fd, DVD_READ_STRUCT, &s);
+
+ inputs:
+ dvd_struct structure, containing:
+
+ =================== ==========================================
+ type specifies the information desired, one of
+ DVD_STRUCT_PHYSICAL, DVD_STRUCT_COPYRIGHT,
+ DVD_STRUCT_DISCKEY, DVD_STRUCT_BCA,
+ DVD_STRUCT_MANUFACT
+ physical.layer_num desired layer, indexed from 0
+ copyright.layer_num desired layer, indexed from 0
+ disckey.agid
+ =================== ==========================================
+
+ outputs:
+ dvd_struct structure, containing:
+
+ =================== ================================
+ physical for type == DVD_STRUCT_PHYSICAL
+ copyright for type == DVD_STRUCT_COPYRIGHT
+ disckey.value for type == DVD_STRUCT_DISCKEY
+ bca.{len,value} for type == DVD_STRUCT_BCA
+ manufact.{len,valu} for type == DVD_STRUCT_MANUFACT
+ =================== ================================
+
+ error returns:
+ - EINVAL physical.layer_num exceeds number of layers
+ - EIO Received invalid response from drive
+
+
+
+DVD_WRITE_STRUCT Write structure
+
+ Not implemented, as of 2.6.8.1
+
+
+
+DVD_AUTH Authentication
+
+ usage::
+
+ dvd_authinfo ai;
+
+ ioctl(fd, DVD_AUTH, &ai);
+
+ inputs:
+ dvd_authinfo structure. See <linux/cdrom.h>
+
+
+ outputs:
+ dvd_authinfo structure.
+
+
+ error return:
+ - ENOTTY ai.type not recognized.
+
+
+
+CDROM_SEND_PACKET
+ send a packet to the drive
+
+
+ usage::
+
+ struct cdrom_generic_command cgc;
+
+ ioctl(fd, CDROM_SEND_PACKET, &cgc);
+
+ inputs:
+ cdrom_generic_command structure containing the packet to send.
+
+
+ outputs:
+ none
+
+ cdrom_generic_command structure containing results.
+
+ error return:
+ - EIO
+
+ command failed.
+ - EPERM
+
+ Operation not permitted, either because a
+ write command was attempted on a drive which
+ is opened read-only, or because the command
+ requires CAP_SYS_RAWIO
+ - EINVAL
+
+ cgc.data_direction not set
+
+
+
+CDROM_NEXT_WRITABLE
+ get next writable block
+
+
+ usage::
+
+ long next;
+
+ ioctl(fd, CDROM_NEXT_WRITABLE, &next);
+
+ inputs:
+ none
+
+
+ outputs:
+ The next writable block.
+
+
+ notes:
+ If the device does not support this ioctl directly, the
+
+ ioctl will return CDROM_LAST_WRITTEN + 7.
+
+
+
+CDROM_LAST_WRITTEN
+ get last block written on disc
+
+
+ usage::
+
+ long last;
+
+ ioctl(fd, CDROM_LAST_WRITTEN, &last);
+
+ inputs:
+ none
+
+
+ outputs:
+ The last block written on disc
+
+
+ notes:
+ If the device does not support this ioctl directly, the
+ result is derived from the disc's table of contents. If the
+ table of contents can't be read, this ioctl returns an
+ error.
diff --git a/Documentation/userspace-api/ioctl/hdio.rst b/Documentation/userspace-api/ioctl/hdio.rst
new file mode 100644
index 000000000..6ee8fc886
--- /dev/null
+++ b/Documentation/userspace-api/ioctl/hdio.rst
@@ -0,0 +1,547 @@
+==============================
+Summary of `HDIO_` ioctl calls
+==============================
+
+- Edward A. Falk <efalk@google.com>
+
+November, 2004
+
+This document attempts to describe the ioctl(2) calls supported by
+the HD/IDE layer. These are by-and-large implemented (as of Linux 5.11)
+drivers/ata/libata-scsi.c.
+
+ioctl values are listed in <linux/hdreg.h>. As of this writing, they
+are as follows:
+
+ ioctls that pass argument pointers to user space:
+
+ ======================= =======================================
+ HDIO_GETGEO get device geometry
+ HDIO_GET_32BIT get current io_32bit setting
+ HDIO_GET_IDENTITY get IDE identification info
+ HDIO_DRIVE_TASKFILE execute raw taskfile
+ HDIO_DRIVE_TASK execute task and special drive command
+ HDIO_DRIVE_CMD execute a special drive command
+ ======================= =======================================
+
+ ioctls that pass non-pointer values:
+
+ ======================= =======================================
+ HDIO_SET_32BIT change io_32bit flags
+ ======================= =======================================
+
+
+The information that follows was determined from reading kernel source
+code. It is likely that some corrections will be made over time.
+
+------------------------------------------------------------------------------
+
+General:
+
+ Unless otherwise specified, all ioctl calls return 0 on success
+ and -1 with errno set to an appropriate value on error.
+
+ Unless otherwise specified, all ioctl calls return -1 and set
+ errno to EFAULT on a failed attempt to copy data to or from user
+ address space.
+
+ Unless otherwise specified, all data structures and constants
+ are defined in <linux/hdreg.h>
+
+------------------------------------------------------------------------------
+
+HDIO_GETGEO
+ get device geometry
+
+
+ usage::
+
+ struct hd_geometry geom;
+
+ ioctl(fd, HDIO_GETGEO, &geom);
+
+
+ inputs:
+ none
+
+
+
+ outputs:
+ hd_geometry structure containing:
+
+
+ ========= ==================================
+ heads number of heads
+ sectors number of sectors/track
+ cylinders number of cylinders, mod 65536
+ start starting sector of this partition.
+ ========= ==================================
+
+
+ error returns:
+ - EINVAL
+
+ if the device is not a disk drive or floppy drive,
+ or if the user passes a null pointer
+
+
+ notes:
+ Not particularly useful with modern disk drives, whose geometry
+ is a polite fiction anyway. Modern drives are addressed
+ purely by sector number nowadays (lba addressing), and the
+ drive geometry is an abstraction which is actually subject
+ to change. Currently (as of Nov 2004), the geometry values
+ are the "bios" values -- presumably the values the drive had
+ when Linux first booted.
+
+ In addition, the cylinders field of the hd_geometry is an
+ unsigned short, meaning that on most architectures, this
+ ioctl will not return a meaningful value on drives with more
+ than 65535 tracks.
+
+ The start field is unsigned long, meaning that it will not
+ contain a meaningful value for disks over 219 Gb in size.
+
+
+
+HDIO_GET_IDENTITY
+ get IDE identification info
+
+
+ usage::
+
+ unsigned char identity[512];
+
+ ioctl(fd, HDIO_GET_IDENTITY, identity);
+
+ inputs:
+ none
+
+
+
+ outputs:
+ ATA drive identity information. For full description, see
+ the IDENTIFY DEVICE and IDENTIFY PACKET DEVICE commands in
+ the ATA specification.
+
+ error returns:
+ - EINVAL Called on a partition instead of the whole disk device
+ - ENOMSG IDENTIFY DEVICE information not available
+
+ notes:
+ Returns information that was obtained when the drive was
+ probed. Some of this information is subject to change, and
+ this ioctl does not re-probe the drive to update the
+ information.
+
+ This information is also available from /proc/ide/hdX/identify
+
+
+
+HDIO_GET_32BIT
+ get current io_32bit setting
+
+
+ usage::
+
+ long val;
+
+ ioctl(fd, HDIO_GET_32BIT, &val);
+
+ inputs:
+ none
+
+
+
+ outputs:
+ The value of the current io_32bit setting
+
+
+
+ notes:
+ 0=16-bit, 1=32-bit, 2,3 = 32bit+sync
+
+
+
+HDIO_DRIVE_TASKFILE
+ execute raw taskfile
+
+
+ Note:
+ If you don't have a copy of the ANSI ATA specification
+ handy, you should probably ignore this ioctl.
+
+ - Execute an ATA disk command directly by writing the "taskfile"
+ registers of the drive. Requires ADMIN and RAWIO access
+ privileges.
+
+ usage::
+
+ struct {
+
+ ide_task_request_t req_task;
+ u8 outbuf[OUTPUT_SIZE];
+ u8 inbuf[INPUT_SIZE];
+ } task;
+ memset(&task.req_task, 0, sizeof(task.req_task));
+ task.req_task.out_size = sizeof(task.outbuf);
+ task.req_task.in_size = sizeof(task.inbuf);
+ ...
+ ioctl(fd, HDIO_DRIVE_TASKFILE, &task);
+ ...
+
+ inputs:
+
+ (See below for details on memory area passed to ioctl.)
+
+ ============ ===================================================
+ io_ports[8] values to be written to taskfile registers
+ hob_ports[8] high-order bytes, for extended commands.
+ out_flags flags indicating which registers are valid
+ in_flags flags indicating which registers should be returned
+ data_phase see below
+ req_cmd command type to be executed
+ out_size size of output buffer
+ outbuf buffer of data to be transmitted to disk
+ inbuf buffer of data to be received from disk (see [1])
+ ============ ===================================================
+
+ outputs:
+
+ =========== ====================================================
+ io_ports[] values returned in the taskfile registers
+ hob_ports[] high-order bytes, for extended commands.
+ out_flags flags indicating which registers are valid (see [2])
+ in_flags flags indicating which registers should be returned
+ outbuf buffer of data to be transmitted to disk (see [1])
+ inbuf buffer of data to be received from disk
+ =========== ====================================================
+
+ error returns:
+ - EACCES CAP_SYS_ADMIN or CAP_SYS_RAWIO privilege not set.
+ - ENOMSG Device is not a disk drive.
+ - ENOMEM Unable to allocate memory for task
+ - EFAULT req_cmd == TASKFILE_IN_OUT (not implemented as of 2.6.8)
+ - EPERM
+
+ req_cmd == TASKFILE_MULTI_OUT and drive
+ multi-count not yet set.
+ - EIO Drive failed the command.
+
+ notes:
+
+ [1] READ THE FOLLOWING NOTES *CAREFULLY*. THIS IOCTL IS
+ FULL OF GOTCHAS. Extreme caution should be used with using
+ this ioctl. A mistake can easily corrupt data or hang the
+ system.
+
+ [2] Both the input and output buffers are copied from the
+ user and written back to the user, even when not used.
+
+ [3] If one or more bits are set in out_flags and in_flags is
+ zero, the following values are used for in_flags.all and
+ written back into in_flags on completion.
+
+ * IDE_TASKFILE_STD_IN_FLAGS | (IDE_HOB_STD_IN_FLAGS << 8)
+ if LBA48 addressing is enabled for the drive
+ * IDE_TASKFILE_STD_IN_FLAGS
+ if CHS/LBA28
+
+ The association between in_flags.all and each enable
+ bitfield flips depending on endianness; fortunately, TASKFILE
+ only uses inflags.b.data bit and ignores all other bits.
+ The end result is that, on any endian machines, it has no
+ effect other than modifying in_flags on completion.
+
+ [4] The default value of SELECT is (0xa0|DEV_bit|LBA_bit)
+ except for four drives per port chipsets. For four drives
+ per port chipsets, it's (0xa0|DEV_bit|LBA_bit) for the first
+ pair and (0x80|DEV_bit|LBA_bit) for the second pair.
+
+ [5] The argument to the ioctl is a pointer to a region of
+ memory containing a ide_task_request_t structure, followed
+ by an optional buffer of data to be transmitted to the
+ drive, followed by an optional buffer to receive data from
+ the drive.
+
+ Command is passed to the disk drive via the ide_task_request_t
+ structure, which contains these fields:
+
+ ============ ===============================================
+ io_ports[8] values for the taskfile registers
+ hob_ports[8] high-order bytes, for extended commands
+ out_flags flags indicating which entries in the
+ io_ports[] and hob_ports[] arrays
+ contain valid values. Type ide_reg_valid_t.
+ in_flags flags indicating which entries in the
+ io_ports[] and hob_ports[] arrays
+ are expected to contain valid values
+ on return.
+ data_phase See below
+ req_cmd Command type, see below
+ out_size output (user->drive) buffer size, bytes
+ in_size input (drive->user) buffer size, bytes
+ ============ ===============================================
+
+ When out_flags is zero, the following registers are loaded.
+
+ ============ ===============================================
+ HOB_FEATURE If the drive supports LBA48
+ HOB_NSECTOR If the drive supports LBA48
+ HOB_SECTOR If the drive supports LBA48
+ HOB_LCYL If the drive supports LBA48
+ HOB_HCYL If the drive supports LBA48
+ FEATURE
+ NSECTOR
+ SECTOR
+ LCYL
+ HCYL
+ SELECT First, masked with 0xE0 if LBA48, 0xEF
+ otherwise; then, or'ed with the default
+ value of SELECT.
+ ============ ===============================================
+
+ If any bit in out_flags is set, the following registers are loaded.
+
+ ============ ===============================================
+ HOB_DATA If out_flags.b.data is set. HOB_DATA will
+ travel on DD8-DD15 on little endian machines
+ and on DD0-DD7 on big endian machines.
+ DATA If out_flags.b.data is set. DATA will
+ travel on DD0-DD7 on little endian machines
+ and on DD8-DD15 on big endian machines.
+ HOB_NSECTOR If out_flags.b.nsector_hob is set
+ HOB_SECTOR If out_flags.b.sector_hob is set
+ HOB_LCYL If out_flags.b.lcyl_hob is set
+ HOB_HCYL If out_flags.b.hcyl_hob is set
+ FEATURE If out_flags.b.feature is set
+ NSECTOR If out_flags.b.nsector is set
+ SECTOR If out_flags.b.sector is set
+ LCYL If out_flags.b.lcyl is set
+ HCYL If out_flags.b.hcyl is set
+ SELECT Or'ed with the default value of SELECT and
+ loaded regardless of out_flags.b.select.
+ ============ ===============================================
+
+ Taskfile registers are read back from the drive into
+ {io|hob}_ports[] after the command completes iff one of the
+ following conditions is met; otherwise, the original values
+ will be written back, unchanged.
+
+ 1. The drive fails the command (EIO).
+ 2. One or more than one bits are set in out_flags.
+ 3. The requested data_phase is TASKFILE_NO_DATA.
+
+ ============ ===============================================
+ HOB_DATA If in_flags.b.data is set. It will contain
+ DD8-DD15 on little endian machines and
+ DD0-DD7 on big endian machines.
+ DATA If in_flags.b.data is set. It will contain
+ DD0-DD7 on little endian machines and
+ DD8-DD15 on big endian machines.
+ HOB_FEATURE If the drive supports LBA48
+ HOB_NSECTOR If the drive supports LBA48
+ HOB_SECTOR If the drive supports LBA48
+ HOB_LCYL If the drive supports LBA48
+ HOB_HCYL If the drive supports LBA48
+ NSECTOR
+ SECTOR
+ LCYL
+ HCYL
+ ============ ===============================================
+
+ The data_phase field describes the data transfer to be
+ performed. Value is one of:
+
+ =================== ========================================
+ TASKFILE_IN
+ TASKFILE_MULTI_IN
+ TASKFILE_OUT
+ TASKFILE_MULTI_OUT
+ TASKFILE_IN_OUT
+ TASKFILE_IN_DMA
+ TASKFILE_IN_DMAQ == IN_DMA (queueing not supported)
+ TASKFILE_OUT_DMA
+ TASKFILE_OUT_DMAQ == OUT_DMA (queueing not supported)
+ TASKFILE_P_IN unimplemented
+ TASKFILE_P_IN_DMA unimplemented
+ TASKFILE_P_IN_DMAQ unimplemented
+ TASKFILE_P_OUT unimplemented
+ TASKFILE_P_OUT_DMA unimplemented
+ TASKFILE_P_OUT_DMAQ unimplemented
+ =================== ========================================
+
+ The req_cmd field classifies the command type. It may be
+ one of:
+
+ ======================== =======================================
+ IDE_DRIVE_TASK_NO_DATA
+ IDE_DRIVE_TASK_SET_XFER unimplemented
+ IDE_DRIVE_TASK_IN
+ IDE_DRIVE_TASK_OUT unimplemented
+ IDE_DRIVE_TASK_RAW_WRITE
+ ======================== =======================================
+
+ [6] Do not access {in|out}_flags->all except for resetting
+ all the bits. Always access individual bit fields. ->all
+ value will flip depending on endianness. For the same
+ reason, do not use IDE_{TASKFILE|HOB}_STD_{OUT|IN}_FLAGS
+ constants defined in hdreg.h.
+
+
+
+HDIO_DRIVE_CMD
+ execute a special drive command
+
+
+ Note: If you don't have a copy of the ANSI ATA specification
+ handy, you should probably ignore this ioctl.
+
+ usage::
+
+ u8 args[4+XFER_SIZE];
+
+ ...
+ ioctl(fd, HDIO_DRIVE_CMD, args);
+
+ inputs:
+ Commands other than WIN_SMART:
+
+ ======= =======
+ args[0] COMMAND
+ args[1] NSECTOR
+ args[2] FEATURE
+ args[3] NSECTOR
+ ======= =======
+
+ WIN_SMART:
+
+ ======= =======
+ args[0] COMMAND
+ args[1] SECTOR
+ args[2] FEATURE
+ args[3] NSECTOR
+ ======= =======
+
+ outputs:
+ args[] buffer is filled with register values followed by any
+
+
+ data returned by the disk.
+
+ ======== ====================================================
+ args[0] status
+ args[1] error
+ args[2] NSECTOR
+ args[3] undefined
+ args[4+] NSECTOR * 512 bytes of data returned by the command.
+ ======== ====================================================
+
+ error returns:
+ - EACCES Access denied: requires CAP_SYS_RAWIO
+ - ENOMEM Unable to allocate memory for task
+ - EIO Drive reports error
+
+ notes:
+
+ [1] For commands other than WIN_SMART, args[1] should equal
+ args[3]. SECTOR, LCYL and HCYL are undefined. For
+ WIN_SMART, 0x4f and 0xc2 are loaded into LCYL and HCYL
+ respectively. In both cases SELECT will contain the default
+ value for the drive. Please refer to HDIO_DRIVE_TASKFILE
+ notes for the default value of SELECT.
+
+ [2] If NSECTOR value is greater than zero and the drive sets
+ DRQ when interrupting for the command, NSECTOR * 512 bytes
+ are read from the device into the area following NSECTOR.
+ In the above example, the area would be
+ args[4..4+XFER_SIZE]. 16bit PIO is used regardless of
+ HDIO_SET_32BIT setting.
+
+ [3] If COMMAND == WIN_SETFEATURES && FEATURE == SETFEATURES_XFER
+ && NSECTOR >= XFER_SW_DMA_0 && the drive supports any DMA
+ mode, IDE driver will try to tune the transfer mode of the
+ drive accordingly.
+
+
+
+HDIO_DRIVE_TASK
+ execute task and special drive command
+
+
+ Note: If you don't have a copy of the ANSI ATA specification
+ handy, you should probably ignore this ioctl.
+
+ usage::
+
+ u8 args[7];
+
+ ...
+ ioctl(fd, HDIO_DRIVE_TASK, args);
+
+ inputs:
+ Taskfile register values:
+
+ ======= =======
+ args[0] COMMAND
+ args[1] FEATURE
+ args[2] NSECTOR
+ args[3] SECTOR
+ args[4] LCYL
+ args[5] HCYL
+ args[6] SELECT
+ ======= =======
+
+ outputs:
+ Taskfile register values:
+
+
+ ======= =======
+ args[0] status
+ args[1] error
+ args[2] NSECTOR
+ args[3] SECTOR
+ args[4] LCYL
+ args[5] HCYL
+ args[6] SELECT
+ ======= =======
+
+ error returns:
+ - EACCES Access denied: requires CAP_SYS_RAWIO
+ - ENOMEM Unable to allocate memory for task
+ - ENOMSG Device is not a disk drive.
+ - EIO Drive failed the command.
+
+ notes:
+
+ [1] DEV bit (0x10) of SELECT register is ignored and the
+ appropriate value for the drive is used. All other bits
+ are used unaltered.
+
+
+
+HDIO_SET_32BIT
+ change io_32bit flags
+
+
+ usage::
+
+ int val;
+
+ ioctl(fd, HDIO_SET_32BIT, val);
+
+ inputs:
+ New value for io_32bit flag
+
+
+
+ outputs:
+ none
+
+
+
+ error return:
+ - EINVAL Called on a partition instead of the whole disk device
+ - EACCES Access denied: requires CAP_SYS_ADMIN
+ - EINVAL value out of range [0 3]
+ - EBUSY Controller busy
diff --git a/Documentation/userspace-api/ioctl/index.rst b/Documentation/userspace-api/ioctl/index.rst
new file mode 100644
index 000000000..475675eae
--- /dev/null
+++ b/Documentation/userspace-api/ioctl/index.rst
@@ -0,0 +1,15 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+======
+IOCTLs
+======
+
+.. toctree::
+ :maxdepth: 1
+
+ ioctl-number
+
+ ioctl-decoding
+
+ cdrom
+ hdio
diff --git a/Documentation/userspace-api/ioctl/ioctl-decoding.rst b/Documentation/userspace-api/ioctl/ioctl-decoding.rst
new file mode 100644
index 000000000..380d6bb3e
--- /dev/null
+++ b/Documentation/userspace-api/ioctl/ioctl-decoding.rst
@@ -0,0 +1,31 @@
+==============================
+Decoding an IOCTL Magic Number
+==============================
+
+To decode a hex IOCTL code:
+
+Most architectures use this generic format, but check
+include/ARCH/ioctl.h for specifics, e.g. powerpc
+uses 3 bits to encode read/write and 13 bits for size.
+
+ ====== ==================================
+ bits meaning
+ ====== ==================================
+ 31-30 00 - no parameters: uses _IO macro
+ 10 - read: _IOR
+ 01 - write: _IOW
+ 11 - read/write: _IOWR
+
+ 29-16 size of arguments
+
+ 15-8 ascii character supposedly
+ unique to each driver
+
+ 7-0 function #
+ ====== ==================================
+
+
+So for example 0x82187201 is a read with arg length of 0x218,
+character 'r' function 1. Grepping the source reveals this is::
+
+ #define VFAT_IOCTL_READDIR_BOTH _IOR('r', 1, struct dirent [2])
diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documentation/userspace-api/ioctl/ioctl-number.rst
new file mode 100644
index 000000000..5f81e2a24
--- /dev/null
+++ b/Documentation/userspace-api/ioctl/ioctl-number.rst
@@ -0,0 +1,381 @@
+=============
+Ioctl Numbers
+=============
+
+19 October 1999
+
+Michael Elizabeth Chastain
+<mec@shout.net>
+
+If you are adding new ioctl's to the kernel, you should use the _IO
+macros defined in <linux/ioctl.h>:
+
+ ====== == ============================================
+ _IO an ioctl with no parameters
+ _IOW an ioctl with write parameters (copy_from_user)
+ _IOR an ioctl with read parameters (copy_to_user)
+ _IOWR an ioctl with both write and read parameters.
+ ====== == ============================================
+
+'Write' and 'read' are from the user's point of view, just like the
+system calls 'write' and 'read'. For example, a SET_FOO ioctl would
+be _IOW, although the kernel would actually read data from user space;
+a GET_FOO ioctl would be _IOR, although the kernel would actually write
+data to user space.
+
+The first argument to _IO, _IOW, _IOR, or _IOWR is an identifying letter
+or number from the table below. Because of the large number of drivers,
+many drivers share a partial letter with other drivers.
+
+If you are writing a driver for a new device and need a letter, pick an
+unused block with enough room for expansion: 32 to 256 ioctl commands.
+You can register the block by patching this file and submitting the
+patch to Linus Torvalds. Or you can e-mail me at <mec@shout.net> and
+I'll register one for you.
+
+The second argument to _IO, _IOW, _IOR, or _IOWR is a sequence number
+to distinguish ioctls from each other. The third argument to _IOW,
+_IOR, or _IOWR is the type of the data going into the kernel or coming
+out of the kernel (e.g. 'int' or 'struct foo'). NOTE! Do NOT use
+sizeof(arg) as the third argument as this results in your ioctl thinking
+it passes an argument of type size_t.
+
+Some devices use their major number as the identifier; this is OK, as
+long as it is unique. Some devices are irregular and don't follow any
+convention at all.
+
+Following this convention is good because:
+
+(1) Keeping the ioctl's globally unique helps error checking:
+ if a program calls an ioctl on the wrong device, it will get an
+ error rather than some unexpected behaviour.
+
+(2) The 'strace' build procedure automatically finds ioctl numbers
+ defined with _IO, _IOW, _IOR, or _IOWR.
+
+(3) 'strace' can decode numbers back into useful names when the
+ numbers are unique.
+
+(4) People looking for ioctls can grep for them more easily when
+ this convention is used to define the ioctl numbers.
+
+(5) When following the convention, the driver code can use generic
+ code to copy the parameters between user and kernel space.
+
+This table lists ioctls visible from user land for Linux/x86. It contains
+most drivers up to 2.6.31, but I know I am missing some. There has been
+no attempt to list non-X86 architectures or ioctls from drivers/staging/.
+
+==== ===== ======================================================= ================================================================
+Code Seq# Include File Comments
+ (hex)
+==== ===== ======================================================= ================================================================
+0x00 00-1F linux/fs.h conflict!
+0x00 00-1F scsi/scsi_ioctl.h conflict!
+0x00 00-1F linux/fb.h conflict!
+0x00 00-1F linux/wavefront.h conflict!
+0x02 all linux/fd.h
+0x03 all linux/hdreg.h
+0x04 D2-DC linux/umsdos_fs.h Dead since 2.6.11, but don't reuse these.
+0x06 all linux/lp.h
+0x09 all linux/raid/md_u.h
+0x10 00-0F drivers/char/s390/vmcp.h
+0x10 10-1F arch/s390/include/uapi/sclp_ctl.h
+0x10 20-2F arch/s390/include/uapi/asm/hypfs.h
+0x12 all linux/fs.h
+ linux/blkpg.h
+0x1b all InfiniBand Subsystem
+ <http://infiniband.sourceforge.net/>
+0x20 all drivers/cdrom/cm206.h
+0x22 all scsi/sg.h
+0x3E 00-0F linux/counter.h <mailto:linux-iio@vger.kernel.org>
+'!' 00-1F uapi/linux/seccomp.h
+'#' 00-3F IEEE 1394 Subsystem
+ Block for the entire subsystem
+'$' 00-0F linux/perf_counter.h, linux/perf_event.h
+'%' 00-0F include/uapi/linux/stm.h System Trace Module subsystem
+ <mailto:alexander.shishkin@linux.intel.com>
+'&' 00-07 drivers/firewire/nosy-user.h
+'1' 00-1F linux/timepps.h PPS kit from Ulrich Windl
+ <ftp://ftp.de.kernel.org/pub/linux/daemons/ntp/PPS/>
+'2' 01-04 linux/i2o.h
+'3' 00-0F drivers/s390/char/raw3270.h conflict!
+'3' 00-1F linux/suspend_ioctls.h, conflict!
+ kernel/power/user.c
+'8' all SNP8023 advanced NIC card
+ <mailto:mcr@solidum.com>
+';' 64-7F linux/vfio.h
+'=' 00-3f uapi/linux/ptp_clock.h <mailto:richardcochran@gmail.com>
+'@' 00-0F linux/radeonfb.h conflict!
+'@' 00-0F drivers/video/aty/aty128fb.c conflict!
+'A' 00-1F linux/apm_bios.h conflict!
+'A' 00-0F linux/agpgart.h, conflict!
+ drivers/char/agp/compat_ioctl.h
+'A' 00-7F sound/asound.h conflict!
+'B' 00-1F linux/cciss_ioctl.h conflict!
+'B' 00-0F include/linux/pmu.h conflict!
+'B' C0-FF advanced bbus <mailto:maassen@uni-freiburg.de>
+'B' 00-0F xen/xenbus_dev.h conflict!
+'C' all linux/soundcard.h conflict!
+'C' 01-2F linux/capi.h conflict!
+'C' F0-FF drivers/net/wan/cosa.h conflict!
+'D' all arch/s390/include/asm/dasd.h
+'D' 40-5F drivers/scsi/dpt/dtpi_ioctl.h Dead since 2022
+'D' 05 drivers/scsi/pmcraid.h
+'E' all linux/input.h conflict!
+'E' 00-0F xen/evtchn.h conflict!
+'F' all linux/fb.h conflict!
+'F' 01-02 drivers/scsi/pmcraid.h conflict!
+'F' 20 drivers/video/fsl-diu-fb.h conflict!
+'F' 20 drivers/video/intelfb/intelfb.h conflict!
+'F' 20 linux/ivtvfb.h conflict!
+'F' 20 linux/matroxfb.h conflict!
+'F' 20 drivers/video/aty/atyfb_base.c conflict!
+'F' 00-0F video/da8xx-fb.h conflict!
+'F' 80-8F linux/arcfb.h conflict!
+'F' DD video/sstfb.h conflict!
+'G' 00-3F drivers/misc/sgi-gru/grulib.h conflict!
+'G' 00-0F xen/gntalloc.h, xen/gntdev.h conflict!
+'H' 00-7F linux/hiddev.h conflict!
+'H' 00-0F linux/hidraw.h conflict!
+'H' 01 linux/mei.h conflict!
+'H' 02 linux/mei.h conflict!
+'H' 03 linux/mei.h conflict!
+'H' 00-0F sound/asound.h conflict!
+'H' 20-40 sound/asound_fm.h conflict!
+'H' 80-8F sound/sfnt_info.h conflict!
+'H' 10-8F sound/emu10k1.h conflict!
+'H' 10-1F sound/sb16_csp.h conflict!
+'H' 10-1F sound/hda_hwdep.h conflict!
+'H' 40-4F sound/hdspm.h conflict!
+'H' 40-4F sound/hdsp.h conflict!
+'H' 90 sound/usb/usx2y/usb_stream.h
+'H' 00-0F uapi/misc/habanalabs.h conflict!
+'H' A0 uapi/linux/usb/cdc-wdm.h
+'H' C0-F0 net/bluetooth/hci.h conflict!
+'H' C0-DF net/bluetooth/hidp/hidp.h conflict!
+'H' C0-DF net/bluetooth/cmtp/cmtp.h conflict!
+'H' C0-DF net/bluetooth/bnep/bnep.h conflict!
+'H' F1 linux/hid-roccat.h <mailto:erazor_de@users.sourceforge.net>
+'H' F8-FA sound/firewire.h
+'I' all linux/isdn.h conflict!
+'I' 00-0F drivers/isdn/divert/isdn_divert.h conflict!
+'I' 40-4F linux/mISDNif.h conflict!
+'K' all linux/kd.h
+'L' 00-1F linux/loop.h conflict!
+'L' 10-1F drivers/scsi/mpt3sas/mpt3sas_ctl.h conflict!
+'L' E0-FF linux/ppdd.h encrypted disk device driver
+ <http://linux01.gwdg.de/~alatham/ppdd.html>
+'M' all linux/soundcard.h conflict!
+'M' 01-16 mtd/mtd-abi.h conflict!
+ and drivers/mtd/mtdchar.c
+'M' 01-03 drivers/scsi/megaraid/megaraid_sas.h
+'M' 00-0F drivers/video/fsl-diu-fb.h conflict!
+'N' 00-1F drivers/usb/scanner.h
+'N' 40-7F drivers/block/nvme.c
+'O' 00-06 mtd/ubi-user.h UBI
+'P' all linux/soundcard.h conflict!
+'P' 60-6F sound/sscape_ioctl.h conflict!
+'P' 00-0F drivers/usb/class/usblp.c conflict!
+'P' 01-09 drivers/misc/pci_endpoint_test.c conflict!
+'P' 00-0F xen/privcmd.h conflict!
+'Q' all linux/soundcard.h
+'R' 00-1F linux/random.h conflict!
+'R' 01 linux/rfkill.h conflict!
+'R' C0-DF net/bluetooth/rfcomm.h
+'R' E0 uapi/linux/fsl_mc.h
+'S' all linux/cdrom.h conflict!
+'S' 80-81 scsi/scsi_ioctl.h conflict!
+'S' 82-FF scsi/scsi.h conflict!
+'S' 00-7F sound/asequencer.h conflict!
+'T' all linux/soundcard.h conflict!
+'T' 00-AF sound/asound.h conflict!
+'T' all arch/x86/include/asm/ioctls.h conflict!
+'T' C0-DF linux/if_tun.h conflict!
+'U' all sound/asound.h conflict!
+'U' 00-CF linux/uinput.h conflict!
+'U' 00-EF linux/usbdevice_fs.h
+'U' C0-CF drivers/bluetooth/hci_uart.h
+'V' all linux/vt.h conflict!
+'V' all linux/videodev2.h conflict!
+'V' C0 linux/ivtvfb.h conflict!
+'V' C0 linux/ivtv.h conflict!
+'V' C0 media/davinci/vpfe_capture.h conflict!
+'V' C0 media/si4713.h conflict!
+'W' 00-1F linux/watchdog.h conflict!
+'W' 00-1F linux/wanrouter.h conflict! (pre 3.9)
+'W' 00-3F sound/asound.h conflict!
+'W' 40-5F drivers/pci/switch/switchtec.c
+'W' 60-61 linux/watch_queue.h
+'X' all fs/xfs/xfs_fs.h, conflict!
+ fs/xfs/linux-2.6/xfs_ioctl32.h,
+ include/linux/falloc.h,
+ linux/fs.h,
+'X' all fs/ocfs2/ocfs_fs.h conflict!
+'X' 01 linux/pktcdvd.h conflict!
+'Z' 14-15 drivers/message/fusion/mptctl.h
+'[' 00-3F linux/usb/tmc.h USB Test and Measurement Devices
+ <mailto:gregkh@linuxfoundation.org>
+'a' all linux/atm*.h, linux/sonet.h ATM on linux
+ <http://lrcwww.epfl.ch/>
+'a' 00-0F drivers/crypto/qat/qat_common/adf_cfg_common.h conflict! qat driver
+'b' 00-FF conflict! bit3 vme host bridge
+ <mailto:natalia@nikhefk.nikhef.nl>
+'c' all linux/cm4000_cs.h conflict!
+'c' 00-7F linux/comstats.h conflict!
+'c' 00-7F linux/coda.h conflict!
+'c' 00-1F linux/chio.h conflict!
+'c' 80-9F arch/s390/include/asm/chsc.h conflict!
+'c' A0-AF arch/x86/include/asm/msr.h conflict!
+'d' 00-FF linux/char/drm/drm.h conflict!
+'d' 02-40 pcmcia/ds.h conflict!
+'d' F0-FF linux/digi1.h
+'e' all linux/digi1.h conflict!
+'f' 00-1F linux/ext2_fs.h conflict!
+'f' 00-1F linux/ext3_fs.h conflict!
+'f' 00-0F fs/jfs/jfs_dinode.h conflict!
+'f' 00-0F fs/ext4/ext4.h conflict!
+'f' 00-0F linux/fs.h conflict!
+'f' 00-0F fs/ocfs2/ocfs2_fs.h conflict!
+'f' 13-27 linux/fscrypt.h
+'f' 81-8F linux/fsverity.h
+'g' 00-0F linux/usb/gadgetfs.h
+'g' 20-2F linux/usb/g_printer.h
+'h' 00-7F conflict! Charon filesystem
+ <mailto:zapman@interlan.net>
+'h' 00-1F linux/hpet.h conflict!
+'h' 80-8F fs/hfsplus/ioctl.c
+'i' 00-3F linux/i2o-dev.h conflict!
+'i' 0B-1F linux/ipmi.h conflict!
+'i' 80-8F linux/i8k.h
+'i' 90-9F `linux/iio/*.h` IIO
+'j' 00-3F linux/joystick.h
+'k' 00-0F linux/spi/spidev.h conflict!
+'k' 00-05 video/kyro.h conflict!
+'k' 10-17 linux/hsi/hsi_char.h HSI character device
+'l' 00-3F linux/tcfs_fs.h transparent cryptographic file system
+ <http://web.archive.org/web/%2A/http://mikonos.dia.unisa.it/tcfs>
+'l' 40-7F linux/udf_fs_i.h in development:
+ <https://github.com/pali/udftools>
+'m' 00-09 linux/mmtimer.h conflict!
+'m' all linux/mtio.h conflict!
+'m' all linux/soundcard.h conflict!
+'m' all linux/synclink.h conflict!
+'m' 00-19 drivers/message/fusion/mptctl.h conflict!
+'m' 00 drivers/scsi/megaraid/megaraid_ioctl.h conflict!
+'n' 00-7F linux/ncp_fs.h and fs/ncpfs/ioctl.c
+'n' 80-8F uapi/linux/nilfs2_api.h NILFS2
+'n' E0-FF linux/matroxfb.h matroxfb
+'o' 00-1F fs/ocfs2/ocfs2_fs.h OCFS2
+'o' 00-03 mtd/ubi-user.h conflict! (OCFS2 and UBI overlaps)
+'o' 40-41 mtd/ubi-user.h UBI
+'o' 01-A1 `linux/dvb/*.h` DVB
+'p' 00-0F linux/phantom.h conflict! (OpenHaptics needs this)
+'p' 00-1F linux/rtc.h conflict!
+'p' 40-7F linux/nvram.h
+'p' 80-9F linux/ppdev.h user-space parport
+ <mailto:tim@cyberelk.net>
+'p' A1-A5 linux/pps.h LinuxPPS
+ <mailto:giometti@linux.it>
+'q' 00-1F linux/serio.h
+'q' 80-FF linux/telephony.h Internet PhoneJACK, Internet LineJACK
+ linux/ixjuser.h <http://web.archive.org/web/%2A/http://www.quicknet.net>
+'r' 00-1F linux/msdos_fs.h and fs/fat/dir.c
+'s' all linux/cdk.h
+'t' 00-7F linux/ppp-ioctl.h
+'t' 80-8F linux/isdn_ppp.h
+'t' 90-91 linux/toshiba.h toshiba and toshiba_acpi SMM
+'u' 00-1F linux/smb_fs.h gone
+'u' 20-3F linux/uvcvideo.h USB video class host driver
+'u' 40-4f linux/udmabuf.h userspace dma-buf misc device
+'v' 00-1F linux/ext2_fs.h conflict!
+'v' 00-1F linux/fs.h conflict!
+'v' 00-0F linux/sonypi.h conflict!
+'v' 00-0F media/v4l2-subdev.h conflict!
+'v' 20-27 arch/powerpc/include/uapi/asm/vas-api.h VAS API
+'v' C0-FF linux/meye.h conflict!
+'w' all CERN SCI driver
+'y' 00-1F packet based user level communications
+ <mailto:zapman@interlan.net>
+'z' 00-3F CAN bus card conflict!
+ <mailto:hdstich@connectu.ulm.circular.de>
+'z' 40-7F CAN bus card conflict!
+ <mailto:oe@port.de>
+'z' 10-4F drivers/s390/crypto/zcrypt_api.h conflict!
+'|' 00-7F linux/media.h
+0x80 00-1F linux/fb.h
+0x81 00-1F linux/vduse.h
+0x89 00-06 arch/x86/include/asm/sockios.h
+0x89 0B-DF linux/sockios.h
+0x89 E0-EF linux/sockios.h SIOCPROTOPRIVATE range
+0x89 F0-FF linux/sockios.h SIOCDEVPRIVATE range
+0x8B all linux/wireless.h
+0x8C 00-3F WiNRADiO driver
+ <http://www.winradio.com.au/>
+0x90 00 drivers/cdrom/sbpcd.h
+0x92 00-0F drivers/usb/mon/mon_bin.c
+0x93 60-7F linux/auto_fs.h
+0x94 all fs/btrfs/ioctl.h Btrfs filesystem
+ and linux/fs.h some lifted to vfs/generic
+0x97 00-7F fs/ceph/ioctl.h Ceph file system
+0x99 00-0F 537-Addinboard driver
+ <mailto:buk@buks.ipn.de>
+0xA0 all linux/sdp/sdp.h Industrial Device Project
+ <mailto:kenji@bitgate.com>
+0xA1 0 linux/vtpm_proxy.h TPM Emulator Proxy Driver
+0xA2 all uapi/linux/acrn.h ACRN hypervisor
+0xA3 80-8F Port ACL in development:
+ <mailto:tlewis@mindspring.com>
+0xA3 90-9F linux/dtlk.h
+0xA4 00-1F uapi/linux/tee.h Generic TEE subsystem
+0xA4 00-1F uapi/asm/sgx.h <mailto:linux-sgx@vger.kernel.org>
+0xA5 01-05 linux/surface_aggregator/cdev.h Microsoft Surface Platform System Aggregator
+ <mailto:luzmaximilian@gmail.com>
+0xA5 20-2F linux/surface_aggregator/dtx.h Microsoft Surface DTX driver
+ <mailto:luzmaximilian@gmail.com>
+0xAA 00-3F linux/uapi/linux/userfaultfd.h
+0xAB 00-1F linux/nbd.h
+0xAC 00-1F linux/raw.h
+0xAD 00 Netfilter device in development:
+ <mailto:rusty@rustcorp.com.au>
+0xAE 00-1F linux/kvm.h Kernel-based Virtual Machine
+ <mailto:kvm@vger.kernel.org>
+0xAE 40-FF linux/kvm.h Kernel-based Virtual Machine
+ <mailto:kvm@vger.kernel.org>
+0xAE 20-3F linux/nitro_enclaves.h Nitro Enclaves
+0xAF 00-1F linux/fsl_hypervisor.h Freescale hypervisor
+0xB0 all RATIO devices in development:
+ <mailto:vgo@ratio.de>
+0xB1 00-1F PPPoX
+ <mailto:mostrows@styx.uwaterloo.ca>
+0xB3 00 linux/mmc/ioctl.h
+0xB4 00-0F linux/gpio.h <mailto:linux-gpio@vger.kernel.org>
+0xB5 00-0F uapi/linux/rpmsg.h <mailto:linux-remoteproc@vger.kernel.org>
+0xB6 all linux/fpga-dfl.h
+0xB7 all uapi/linux/remoteproc_cdev.h <mailto:linux-remoteproc@vger.kernel.org>
+0xB7 all uapi/linux/nsfs.h <mailto:Andrei Vagin <avagin@openvz.org>>
+0xC0 00-0F linux/usb/iowarrior.h
+0xCA 00-0F uapi/misc/cxl.h
+0xCA 10-2F uapi/misc/ocxl.h
+0xCA 80-BF uapi/scsi/cxlflash_ioctl.h
+0xCB 00-1F CBM serial IEC bus in development:
+ <mailto:michael.klein@puffin.lb.shuttle.de>
+0xCC 00-0F drivers/misc/ibmvmc.h pseries VMC driver
+0xCD 01 linux/reiserfs_fs.h
+0xCE 01-02 uapi/linux/cxl_mem.h Compute Express Link Memory Devices
+0xCF 02 fs/cifs/ioctl.c
+0xDB 00-0F drivers/char/mwave/mwavepub.h
+0xDD 00-3F ZFCP device driver see drivers/s390/scsi/
+ <mailto:aherrman@de.ibm.com>
+0xE5 00-3F linux/fuse.h
+0xEC 00-01 drivers/platform/chrome/cros_ec_dev.h ChromeOS EC driver
+0xEE 00-09 uapi/linux/pfrut.h Platform Firmware Runtime Update and Telemetry
+0xF3 00-3F drivers/usb/misc/sisusbvga/sisusb.h sisfb (in development)
+ <mailto:thomas@winischhofer.net>
+0xF6 all LTTng Linux Trace Toolkit Next Generation
+ <mailto:mathieu.desnoyers@efficios.com>
+0xF8 all arch/x86/include/uapi/asm/amd_hsmp.h AMD HSMP EPYC system management interface driver
+ <mailto:nchatrad@amd.com>
+0xFD all linux/dm-ioctl.h
+0xFE all linux/isst_if.h
+==== ===== ======================================================= ================================================================
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-27 09:36:52 +0000