Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 1242 insertions, 0 deletions

diff --git a/Documentation/userspace-api/ioctl/cdrom.rst b/Documentation/userspace-api/ioctl/cdrom.rst
new file mode 100644
index 000000000..2ad91dbeb
--- /dev/null
+++ b/Documentation/userspace-api/ioctl/cdrom.rst
@@ -0,0 +1,1242 @@
+============================
+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.