All <linux/hdreg.h> users that need <linux/ata.h> have been fixed
to include it directly.

Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Move HD_IRQ define to drivers/block/hd.c (only user).

* Remove unused *_STAT, *_ERR, HD_*, CD, IO, REL and TAG_MASK defines.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

HDIO_GET_IDENTITY returns 256 words currently.

Noticed by Norman Diamond.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

hdparm explicitely marks HDIO_[UNREGISTER,SCAN]_HWIF ioctls as DANGEROUS
and given the number of bugs we can assume that there are no real users:

* DMA has no chance of working because DMA resources are released by
  ide_unregister() and they are never allocated again.

* Since ide_init_hwif_ports() is used for ->io_ports[] setup the ioctls
  don't work for almost all hosts with "non-standard" (== non ISA-like)
  layout of IDE taskfile registers (there is a lot of such host drivers).

* ide_port_init_devices() is not called when probing IDE devices so:
  - drive->autotune is never set and IDE host/devices are not programmed
    for the correct PIO/DMA transfer modes (=> possible data corruption)
  - host specific I/O 32-bit and IRQ unmasking settings are not applied
    (=> possible data corruption)
  - host specific ->port_init_devs method is not called (=> no luck with
    ht6560b, qd65xx and opti621 host drivers)

* ->rw_disk method is not preserved (=> no HPT3xxN chipsets support).

* ->serialized flag is not preserved (=> possible data corruption when
   using icside, aec62xx (ATP850UF chipset), cmd640, cs5530, hpt366
   (HPT3xxN chipsets), rz1000, sc1200, dtc2278 and ht6560b host drivers).

* ->ack_intr method is not preserved (=> needed by ide-cris, buddha,
  gayle and macide host drivers).

* ->sata_scr[] and sata_misc[] is cleared by ide_unregister() and it
  isn't initialized again (SiI3112 support needs them).

* To issue an ioctl() there need to be at least one IDE device present
  in the system.

* ->cable_detect method is not preserved + it is not called when probing
  IDE devices so cable detection is broken (however since DMA support is
  also broken it doesn't really matter ;-).

* Some objects which may have already been freed in ide_unregister()
  are restored by ide_hwif_restore() (i.e. ->hwgroup).

* ide_register_hw() may unregister unrelated IDE ports if free ide_hwifs[]
  slot cannot be found.

* When IDE host drivers are modular unregistered port may be re-used by
  different host driver that owned it first causing subtle bugs.

Since we now have a proper warm-plug support remove these ioctls,
then remove no longer needed:
- ide_register_hw() and ide_hwif_restore() functions
- 'init_default' and 'restore' arguments of ide_unregister()
- zeroeing of hwif->{dma,extra}_* fields in ide_unregister()

As an added bonus IDE core code size shrinks by ~3kB (x86-32).

v2:
* fix ide_unregister() arguments in cleanup_module() (Andrew Morton).

v3:
* fix ide_unregister() arguments in palm_bk3710.c.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Signed-off-by: Paulius Zaleckas <pauliusz@yahoo.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>

* ->nice0 and ->nice2 ide_drive_t fields are always zero so remove them.

* IDE_NICE_0 and IDE_NICE_2 defines from <linux/hdreg.h> are no longer
  used by any kernel code so cover them with #ifndef/#endif __KERNEL__.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Add 'data_buf' and 'nsect' variables in ide_taskfile_ioctl()
  to cache data buffer pointer and number of sectors to transfer
  (this allows us to have only one ide_diag_taskfile() call).

* Add IDE_TFLAG_WRITE taskfile flag and use it to check whether
  the REQ_RW request flag should be set.

* Move ->command_type handling from ide_diag_taskfile() to
  ide_taskfile_ioctl() and use ->req_cmd instead of ->command_type.

* Add 'nsect' parameter to ide_raw_taskfile().

* Merge ide_diag_taskfile() into ide_raw_taskfile().

* Initialize ->data_phase explicitly in idedisk_prepare_flush(),
  ide_start_power_step() and ide_disk_special().

* Remove no longer needed 'command_type' field from ide_task_t.

* Add #ifndef/#endif __KERNEL__ to <linux/hdreg.h> around no
  longer used by kernel IDE_DRIVE_TASK_* and TASKFILE_* defines.

There should be no functionality changes caused by this patch.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Remove atapi_error_t.

While at it:
* replace 'HWIF(drive)' by 'drive->hwif'

v2:
* Add {ILI,EOM,LFS}_ERR defines to <linux/hdreg.h>.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>