2004-11-24 01:23:40

by Edward Falk

[permalink] [raw]
Subject: [PATCH] Documentation for IDE and CDROM ioctls.

diff -urpP linux.old/Documentation/ioctl/cdrom.txt linux/Documentation/ioctl/cdrom.txt
--- linux.old/Documentation/ioctl/cdrom.txt 1969-12-31 16:00:00.000000000 -0800
+++ linux/Documentation/ioctl/cdrom.txt 2004-11-23 14:51:39.000000000 -0800
@@ -0,0 +1,935 @@
+ Summary of CDROM ioctl calls.
+ ============================
+
+ Edward A. Falk <[email protected]>
+
+ 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 CDROM_GET_MCN (deprecated)
+ 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
+ CDROMSETSPINDOWN
+ 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_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.
+
+ Unless otherwise specified, all ioctl calls return 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:
+ 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
+
+ notes:
+ 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.
+
+
+CDROMSTART Start the cdrom drive
+
+ usage:
+
+ ioctl(fd, CDROMSTART, 0);
+
+ inputs: none
+
+ outputs: none
+
+ error return:
+ ENOSYS cd drive not audio-capable.
+
+
+CDROMEJECT Ejects the cdrom media
+
+ usage:
+
+ ioctl(fd, CDROMEJECT, 0);
+
+ inputs: none
+
+ outputs: none
+
+ error return:
+ ENOSYS cd drive not capable of ejecting
+ EBUSY other processes have drive open or door is locked
+
+
+
+CDROMCLOSETRAY pendant of CDROMEJECT
+
+ usage:
+
+ ioctl(fd, CDROMEJECT, 0);
+
+ inputs: none
+
+ outputs: none
+
+ error return:
+ ENOSYS cd drive not capable of ejecting
+ EBUSY other processes have drive open or door is locked
+
+
+
+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 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
+
+ usage:
+
+ char spindown;
+ ioctl(fd, CDROMGETSPINDOWN, &spindown);
+
+ inputs: none
+
+ outputs:
+ The value of the current 4-bit spindown value.
+
+
+
+
+CDROMSETSPINDOWN
+
+ 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
+ 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.
+ Unfortunatly, 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 Recieved 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.
+
+
+
+CDROM_LAST_WRITTEN get last block written on disc
+
+ usage:
+
+ long last;
+ ioctl(fd, CDROM_NEXT_WRITABLE, &last);
+
+ inputs: none
+
+ outputs:
+ The last block written on disc
+
+
diff -urpP linux.old/Documentation/ioctl/hdio.txt linux/Documentation/ioctl/hdio.txt
--- linux.old/Documentation/ioctl/hdio.txt 1969-12-31 16:00:00.000000000 -0800
+++ linux/Documentation/ioctl/hdio.txt 2004-11-23 14:58:01.000000000 -0800
@@ -0,0 +1,949 @@
+ Summary of HDIO_ ioctl calls.
+ ============================
+
+ Edward A. Falk <[email protected]>
+
+ 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 2.6)
+in drivers/ide/ide.c and drivers/block/scsi_ioctl.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_UNMASKINTR get current unmask setting
+ HDIO_GET_MULTCOUNT get current IDE blockmode setting
+ HDIO_GET_QDMA get use-qdma flag
+ HDIO_SET_XFER set transfer rate via proc
+ HDIO_OBSOLETE_IDENTITY OBSOLETE, DO NOT USE
+ HDIO_GET_KEEPSETTINGS get keep-settings-on-reset flag
+ HDIO_GET_32BIT get current io_32bit setting
+ HDIO_GET_NOWERR get ignore-write-error flag
+ HDIO_GET_DMA get use-dma flag
+ HDIO_GET_NICE get nice flags
+ HDIO_GET_IDENTITY get IDE identification info
+ HDIO_GET_WCACHE get write cache mode on|off
+ HDIO_GET_ACOUSTIC get acoustic value
+ HDIO_GET_ADDRESS
+ HDIO_GET_BUSSTATE get the bus state of the hwif
+ HDIO_TRISTATE_HWIF execute a channel tristate
+ HDIO_DRIVE_RESET execute a device reset
+ HDIO_DRIVE_TASKFILE execute raw taskfile
+ HDIO_DRIVE_TASK execute task and special drive command
+ HDIO_DRIVE_CMD execute a special drive command
+ HDIO_DRIVE_CMD_AEB HDIO_DRIVE_TASK
+
+ ioctls that pass non-pointer values:
+
+ HDIO_SET_MULTCOUNT change IDE blockmode
+ HDIO_SET_UNMASKINTR permit other irqs during I/O
+ HDIO_SET_KEEPSETTINGS keep ioctl settings on reset
+ HDIO_SET_32BIT change io_32bit flags
+ HDIO_SET_NOWERR change ignore-write-error flag
+ HDIO_SET_DMA change use-dma flag
+ HDIO_SET_PIO_MODE reconfig interface to new speed
+ HDIO_SCAN_HWIF register and (re)scan interface
+ HDIO_SET_NICE set nice flags
+ HDIO_UNREGISTER_HWIF unregister interface
+ HDIO_SET_WCACHE change write cache enable-disable
+ HDIO_SET_ACOUSTIC change acoustic behavior
+ HDIO_SET_BUSSTATE set the bus state of the hwif
+ HDIO_SET_QDMA change use-qdma flag
+ HDIO_SET_ADDRESS change lba addressing modes
+
+ HDIO_SET_IDE_SCSI
+ HDIO_SET_SCSI_IDE
+
+
+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 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_UNMASKINTR get current unmask setting
+
+ usage:
+
+ long val;
+ ioctl(fd, HDIO_GET_UNMASKINTR, &val);
+
+ inputs: none
+
+ outputs:
+ The value of the drive's current unmask setting
+
+
+
+HDIO_SET_UNMASKINTR permit other irqs during I/O
+
+ usage:
+
+ long val;
+ ioctl(fd, HDIO_SET_UNMASKINTR, val);
+
+ inputs:
+ New value for unmask flag
+
+ outputs: none
+
+ error return:
+ EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ EACCES Access denied: requires CAP_SYS_ADMIN
+ EINVAL value out of range [0 1]
+ EBUSY Controller busy
+
+
+
+
+HDIO_GET_MULTCOUNT get current IDE blockmode setting
+
+ usage:
+
+ long val;
+ ioctl(fd, HDIO_GET_MULTCOUNT, &val);
+
+ inputs: none
+
+ outputs:
+ The value of the current IDE block mode setting. This
+ controls how many sectors the drive will transfer per
+ interrupt.
+
+
+
+HDIO_SET_MULTCOUNT change IDE blockmode
+
+ usage:
+
+ int val;
+ ioctl(fd, HDIO_SET_MULTCOUNT, val);
+
+ inputs:
+ New value for IDE block mode setting. This controls how many
+ sectors the drive will transfer per interrupt.
+
+ outputs: none
+
+ error return:
+ EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ EACCES Access denied: requires CAP_SYS_ADMIN
+ EINVAL value out of range supported by disk.
+ EBUSY Controller busy or blockmode already set.
+ EIO Drive did not accept new block mode.
+
+ notes:
+
+ Source code comments read:
+
+ This is tightly woven into the driver->do_special can not
+ touch. DON'T do it again until a total personality rewrite
+ is committed."
+
+ If blockmode has already been set, this ioctl will fail with
+ EBUSY
+
+
+
+HDIO_GET_QDMA get use-qdma flag
+
+ Not implemented, as of 2.6.8.1
+
+
+
+HDIO_SET_XFER set transfer rate via proc
+
+ Not implemented, as of 2.6.8.1
+
+
+
+HDIO_OBSOLETE_IDENTITY OBSOLETE, DO NOT USE
+
+ Same as HDIO_GET_IDENTITY (see below), except that it only
+ returns the first 142 bytes of drive identity information.
+
+
+
+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 (bdev != bdev->bd_contains) (not sure what this means)
+ 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_KEEPSETTINGS get keep-settings-on-reset flag
+
+ usage:
+
+ long val;
+ ioctl(fd, HDIO_GET_KEEPSETTINGS, &val);
+
+ inputs: none
+
+ outputs:
+ The value of the current "keep settings" flag
+
+ notes:
+
+ When set, indicates that kernel should restore settings
+ after a drive reset.
+
+
+
+HDIO_SET_KEEPSETTINGS keep ioctl settings on reset
+
+ usage:
+
+ long val;
+ ioctl(fd, HDIO_SET_KEEPSETTINGS, val);
+
+ inputs:
+ New value for keep_settings flag
+
+ outputs: none
+
+ error return:
+ EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ EACCES Access denied: requires CAP_SYS_ADMIN
+ EINVAL value out of range [0 1]
+ EBUSY Controller busy
+
+
+
+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_GET_NOWERR get ignore-write-error flag
+
+ usage:
+
+ long val;
+ ioctl(fd, HDIO_GET_NOWERR, &val);
+
+ inputs: none
+
+ outputs:
+ The value of the current ignore-write-error flag
+
+
+
+HDIO_GET_DMA get use-dma flag
+
+ usage:
+
+ long val;
+ ioctl(fd, HDIO_GET_DMA, &val);
+
+ inputs: none
+
+ outputs:
+ The value of the current use-dma flag
+
+
+
+HDIO_GET_NICE get nice flags
+
+ usage:
+
+ long nice;
+ ioctl(fd, HDIO_GET_NICE, &nice);
+
+ inputs: none
+
+ outputs:
+
+ The drive's "nice" values.
+
+ notes:
+
+ Per-drive flags which determine when the system will give more
+ bandwidth to other devices sharing the same IDE bus.
+ See <linux/hdreg.h>, near symbol IDE_NICE_DSC_OVERLAP.
+
+
+
+
+HDIO_SET_NICE set nice flags
+
+ usage:
+
+ int nice;
+ ...
+ ioctl(fd, HDIO_SET_NICE, nice);
+
+ inputs:
+ args[0] io address to probe
+ args[1] control address to probe
+ args[2] irq number
+
+ outputs: none
+
+ error returns:
+ EACCES Access denied: requires CAP_SYS_ADMIN
+ EPERM Flags other than DSC_OVERLAP and NICE_1 set.
+ EPERM DSC_OVERLAP specified but not supported by drive
+
+ notes:
+
+ This ioctl sets the DSC_OVERLAP and NICE_1 flags from values
+ provided by the user.
+
+
+
+
+
+HDIO_GET_WCACHE get write cache mode on|off
+
+ usage:
+
+ long val;
+ ioctl(fd, HDIO_GET_WCACHE, &val);
+
+ inputs: none
+
+ outputs:
+ The value of the current write cache mode
+
+
+
+HDIO_GET_ACOUSTIC get acoustic value
+
+ usage:
+
+ long val;
+ ioctl(fd, HDIO_GET_ACOUSTIC, &val);
+
+ inputs: none
+
+ outputs:
+ The value of the current acoustic settings
+
+ notes:
+
+ See HDIO_SET_ACOUSTIC
+
+
+
+HDIO_GET_ADDRESS
+
+ usage:
+
+ long val;
+ ioctl(fd, HDIO_GET_ADDRESS, &val);
+
+ inputs: none
+
+ outputs:
+ The value of the current addressing mode:
+ 0 = 28-bit
+ 1 = 48-bit
+ 2 = 48-bit doing 28-bit
+ 3 = 64-bit
+
+
+
+HDIO_GET_BUSSTATE get the bus state of the hwif
+
+ usage:
+
+ long state;
+ ioctl(fd, HDIO_SCAN_HWIF, &state);
+
+ inputs: none
+
+ outputs:
+ Current power state of the IDE bus. One of BUSSTATE_OFF,
+ BUSSTATE_ON, or BUSSTATE_TRISTATE
+
+ error returns:
+ EACCES Access denied: requires CAP_SYS_ADMIN
+
+
+
+
+HDIO_SET_BUSSTATE set the bus state of the hwif
+
+ usage:
+
+ int state;
+ ...
+ ioctl(fd, HDIO_SCAN_HWIF, state);
+
+ inputs:
+ Desired IDE power state. One of BUSSTATE_OFF, BUSSTATE_ON,
+ or BUSSTATE_TRISTATE
+
+ outputs: none
+
+ error returns:
+ EACCES Access denied: requires CAP_SYS_RAWIO
+ EOPNOTSUPP Hardware interface does not support bus power control
+
+
+
+
+HDIO_TRISTATE_HWIF execute a channel tristate
+
+ Not implemented, as of 2.6.8.1. See HDIO_SET_BUSSTATE
+
+
+
+HDIO_DRIVE_RESET execute a device reset
+
+ usage:
+
+ int args[3]
+ ...
+ ioctl(fd, HDIO_DRIVE_RESET, args);
+
+ inputs: none
+
+ outputs: none
+
+ error returns:
+ EACCES Access denied: requires CAP_SYS_ADMIN
+
+ notes:
+
+ Aborts any current command, prevent anything else from being
+ queued, execute a reset on the device, and issue BLKRRPART
+ ioctl on the block device.
+
+ Executes an ATAPI soft reset if applicable, otherwise
+ executes an ATA soft reset on the controller.
+
+
+
+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.
+
+ 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[] values to be written to taskfile registers
+ hob_ports[] values to be written to taskfile registers
+ 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
+
+ outputs:
+
+ io_ports[] values returned in the taskfile registers
+ hob_ports[] values returned in the taskfile registers
+ out_flags flags indicating which registers are valid
+ in_flags flags indicating which registers should be returned
+ outbuf buffer of data to be transmitted to disk
+ inbuf buffer of data to be received from disk
+
+ error returns:
+ EACCES CAP_SYS_ADMIN or CAP_SYS_RAWIO privelege 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.
+
+
+ notes:
+
+ Execute an ATA disk command directly by writing the "taskfile"
+ registers of the drive. Requires ADMIN and RAWIO access
+ privileges.
+
+ Extreme caution should be used with using this ioctl. A
+ mistake can easily corrupt data or hang the system.
+
+ 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.
+ 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
+
+ Unused fields of io_ports[] and hob_ports[] should be set to
+ zero.
+
+ 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
+ TASKFILE_OUT_DMA
+ TASKFILE_OUT_DMAQ
+ TASKFILE_P_IN
+ TASKFILE_P_IN_DMA
+ TASKFILE_P_IN_DMAQ
+ TASKFILE_P_OUT
+ TASKFILE_P_OUT_DMA
+ TASKFILE_P_OUT_DMAQ
+
+ The req_cmd field classifies the command type. It may be
+ one of:
+
+ IDE_DRIVE_TASK_NO_DATA
+ IDE_DRIVE_TASK_SET_XFER
+ IDE_DRIVE_TASK_IN
+ IDE_DRIVE_TASK_OUT
+ IDE_DRIVE_TASK_RAW_WRITE
+
+ Currently (2.6.8), both the input and output buffers are
+ copied from the user and written back to the user, even when
+ not used.
+
+
+
+
+
+
+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:
+
+ Taskfile register values:
+ 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
+
+ error returns:
+ EACCES Access denied: requires CAP_SYS_RAWIO
+ ENOMEM Unable to allocate memory for task
+
+
+
+
+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
+
+
+
+
+HDIO_DRIVE_CMD_AEB HDIO_DRIVE_TASK
+
+ Not implemented, as of 2.6.8.1
+
+
+
+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 (bdev != bdev->bd_contains) (not sure what this means)
+ EACCES Access denied: requires CAP_SYS_ADMIN
+ EINVAL value out of range [0 3]
+ EBUSY Controller busy
+
+
+
+
+HDIO_SET_NOWERR change ignore-write-error flag
+
+ usage:
+
+ int val;
+ ioctl(fd, HDIO_SET_NOWERR, val);
+
+ inputs:
+ New value for ignore-write-error flag. Used for ignoring
+ WRERR_STAT
+
+ outputs: none
+
+ error return:
+ EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ EACCES Access denied: requires CAP_SYS_ADMIN
+ EINVAL value out of range [0 1]
+ EBUSY Controller busy
+
+
+
+HDIO_SET_DMA change use-dma flag
+
+ usage:
+
+ long val;
+ ioctl(fd, HDIO_SET_DMA, val);
+
+ inputs:
+ New value for use-dma flag
+
+ outputs: none
+
+ error return:
+ EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ EACCES Access denied: requires CAP_SYS_ADMIN
+ EINVAL value out of range [0 1]
+ EBUSY Controller busy
+
+
+
+HDIO_SET_PIO_MODE reconfig interface to new speed
+
+ usage:
+
+ long val;
+ ioctl(fd, HDIO_SET_PIO_MODE, val);
+
+ inputs:
+ New interface speed.
+
+ outputs: none
+
+ error return:
+ EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ EACCES Access denied: requires CAP_SYS_ADMIN
+ EINVAL value out of range [0 255]
+ EBUSY Controller busy
+
+
+
+HDIO_SCAN_HWIF register and (re)scan interface
+
+ usage:
+
+ int args[3]
+ ...
+ ioctl(fd, HDIO_SCAN_HWIF, args);
+
+ inputs:
+ args[0] io address to probe
+ args[1] control address to probe
+ args[2] irq number
+
+ outputs: none
+
+ error returns:
+ EACCES Access denied: requires CAP_SYS_RAWIO
+ EIO Probe failed.
+
+ notes:
+
+ This ioctl initializes the addresses and irq for a disk
+ controller, probes for drives, and creates /proc/ide
+ interfaces as appropiate.
+
+
+
+HDIO_UNREGISTER_HWIF unregister interface
+
+ usage:
+
+ int index;
+ ioctl(fd, HDIO_UNREGISTER_HWIF, index);
+
+ inputs:
+ index index of hardware interface to unregister
+
+ outputs: none
+
+ error returns:
+ EACCES Access denied: requires CAP_SYS_RAWIO
+
+ notes:
+
+ This ioctl removes a hardware interface from the kernel.
+
+ Currently (2.6.8) this ioctl silently fails if any drive on
+ the interface is busy.
+
+
+
+HDIO_SET_WCACHE change write cache enable-disable
+
+ usage:
+
+ int val;
+ ioctl(fd, HDIO_SET_WCACHE, val);
+
+ inputs:
+ New value for write cache enable
+
+ outputs: none
+
+ error return:
+ EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ EACCES Access denied: requires CAP_SYS_ADMIN
+ EINVAL value out of range [0 1]
+ EBUSY Controller busy
+
+
+
+HDIO_SET_ACOUSTIC change acoustic behavior
+
+ usage:
+
+ int val;
+ ioctl(fd, HDIO_SET_ACOUSTIC, val);
+
+ inputs:
+ New value for drive acoustic settings
+
+ outputs: none
+
+ error return:
+ EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ EACCES Access denied: requires CAP_SYS_ADMIN
+ EINVAL value out of range [0 254]
+ EBUSY Controller busy
+
+
+
+HDIO_SET_QDMA change use-qdma flag
+
+ Not implemented, as of 2.6.8.1
+
+
+
+HDIO_SET_ADDRESS change lba addressing modes
+
+ usage:
+
+ int val;
+ ioctl(fd, HDIO_SET_ADDRESS, val);
+
+ inputs:
+ New value for addressing mode
+ 0 = 28-bit
+ 1 = 48-bit
+ 2 = 48-bit doing 28-bit
+
+ outputs: none
+
+ error return:
+ EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ EACCES Access denied: requires CAP_SYS_ADMIN
+ EINVAL value out of range [0 2]
+ EBUSY Controller busy
+ EIO Drive does not support lba48 mode.
+
+
+HDIO_SET_IDE_SCSI
+
+ usage:
+
+ long val;
+ ioctl(fd, HDIO_SET_IDE_SCSI, val);
+
+ inputs:
+ New value for scsi emulation mode (?)
+
+ outputs: none
+
+ error return:
+ EINVAL (bdev != bdev->bd_contains) (not sure what this means)
+ EACCES Access denied: requires CAP_SYS_ADMIN
+ EINVAL value out of range [0 1]
+ EBUSY Controller busy
+
+
+
+HDIO_SET_SCSI_IDE
+
+ Not implemented, as of 2.6.8.1
+
+


Attachments:
patch-ioctl-doc (39.25 kB)

2004-11-24 01:40:11

by Jeff Garzik

[permalink] [raw]
Subject: Re: [PATCH] Documentation for IDE and CDROM ioctls.



Very nice, thanks for writing that up.

Jeff



2004-11-28 18:43:01

by Alan

[permalink] [raw]
Subject: Re: [PATCH] Documentation for IDE and CDROM ioctls.

On Mer, 2004-11-24 at 01:18, Edward Falk wrote:
> The CDROM_LOCKDOOR ioctl seems to lock/unlock all doors on all drives,
> because it uses a global variable.

Known bug/hideous ancient vendor hack that should never have been
allowed
upstream.