hdio.txt

linux 内核源代码

	    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 endianess; 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 endianess.  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_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 appropriate.



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