On user request (through sysfs), the IDLE IMMEDIATE command with UNLOAD
FEATURE as specified in ATA-7 is issued to the device and processing of
the request queue is stopped thereafter until the specified timeout
expires or user space asks to resume normal operation. This is supposed
to prevent the heads of a hard drive from accidentally crashing onto the
platter when a heavy shock is anticipated (like a falling laptop expected
to hit the floor). Port resets are deferred whenever a device on that
port is in the parked state.

v3:
Elias Oltmanns <eo@nebensachen.de> wrote:
[...]
> >> 1. Make sure that no negative value is being passed to
> >>    jiffies_to_msecs() in ide_park_show().
> >> 2. Drop the superfluous variable hwif in ide_special_rq().
> >> 3. Skip initialisation of task and tf in ide_special_rq() if we are not
> >>    handling a (un)park request.
> >
> > Well, #3 should have been done differently because we donn't want to
> > check for REQ_(UN)?PARK_HEADS more often than is necessary.
> 
> While preparing the backport to 2.6.27, it has just occurred to me that
> we need to clear the IDE_DFLAG_PARKED flag in ide_disk_pre_reset()
> because this flag must not be set after *any* sort of access to the
> device.

v4:
Fix a memory leak due to a missing blk_put_request() in
issue_park_cmd(). Additionally, we should plug the queue when enqueueing
the unpark request because there is no guarantee that the park timeout
has not expired by then. Even though the chance for that to happen is
very slim, the request might end up hanging in the queue until the next
I/O operation is queued up. While at it, clean up the code a little:
- make issue_park_cmd() a function of type void since nobody cares for
  the return value anyway;
- use blk_start_queueing() instead of __blk_run_queue() since we don't
  have to worry about recursion;
- remove a superfluous pointer deference in task_no_data_intr().
Signed-off-by: NElias Oltmanns <eo@nebensachen.de>
Cc: Jeff Garzik <jeff@garzik.org>,
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Follow-up to commit 5c05ff68
("ide: switch to DMA-mapping API"):

* pci_{alloc,free}_consistent() -> dma_{alloc,free}_coherent()
  in ide_{allocate,release}_dma_engine().

* Add ->prd_max_nents and ->prd_ent_size fields to ide_hwif_t
  (+ set default values in ide_allocate_dma_engine()).

* Make ide_{allocate,release}_dma_engine() available also
  for CONFIG_BLK_DEV_IDEDMA_SFF=n.  Then convert au1xxx-ide.c,
  scc_pata.c and sgiioc4.c to use them.

* Add missing ->init_dma method to scc_pata.

This patch also fixes:
- ->dmatable_cpu leak for au1xxx-ide
- too early realease of ->dmatable_cpu for scc_pata
- wrong amount of ->dmatable_cpu memory being freed for sgiioc4

While at it:
- remove superfluous ->dma_base check from ide_unregister()
- return -ENOMEM on error in ide_release_dma_engine()
- beautify error message in ide_release_dma_engine()
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

While at it:
- idedisk_ioctl() -> ide_disk_ioctl()
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Convert 'pio_mode' device setting to use DS_SYNC flag.

* Remove unused special_t.b.{set_tune,serviced} and ide_drive_t.tune_req.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Use 'drive->dn & 1' in ide_init_disk().

* remove [ata_]select_t.

While at it:

* Use ATA_DEVICE_OBS define in ide_port_init_devices_data().
Acked-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Call ide_port_init_devices() in ide_host_register()
  also if 'struct ide_port_info *d' is not available.

* Init drive->dn in ide_port_init_devices() instead of
  ide_probe_port() so it is valid also in ->init_dev.

* Pass device number to ide_dev_apply_params().

* Use 'drive->dn & 1' instead of drive->select.b.unit.

There should be no functional changes caused by this patch.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Move ide*_pm_* enums from ide-io.c to <linux/ide.h>.

* idedisk_pm_* -> ide_pm_*

* ide_pm_state_* -> ide_pm_*

* No need to set ide_pm_* enums to the fixed values.

* Uppercase ide_pm_* enums.

* Fix/update comments.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Add 'unsigned long dev_flags' to ide_drive_t and convert bitfields
to IDE_DFLAG_* flags.

While at it:
- IDE_DFLAG_ADDRESSING -> IDE_DFLAG_LBA48
- fixup some comments
- remove needless g->flags zeroing from ide*_probe()

There should be no functional changes caused by this patch.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

ACPI _GTM / _PS0 / _STM were not called if only slave device was present.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Use a special request for serialisation purposes and get rid of the
awkward ide_spin_wait_hwgroup(). This also involves converting the
ide_devset structure so it can be shared by the /proc and the ioctl code.
Signed-off-by: NElias Oltmanns <eo@nebensachen.de>
[bart: use rq->cmd[] directly]
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Move ioctls handling to ide-ioctls.c
  (except HDIO_DRIVE_TASKFILE for now).

* Make ide_{cmd,task}() static.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Fix intendation for the main 'switch ()'.

* 'switch ()' -> 'if ()' for HDIO_DRIVE_TASKFILE case.

* Move HDIO_SET_NICE case under HDIO_GET_NICE one.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Add struct ide_ioctl_devset representing ioctl device setting.

* Add ide_setting_ioctl() helper for matching given ioctl
  and its parameters against table of ioctl device settings.

* Convert ide_setting_ioctl() and idedisk_ioctl() to use
  ide_setting_ioctl().

* Un-export ide_setting_mtx.

While at it:

* {get,set}_lba_addressing() -> {get,set}_addressing()

There should be no functional changes caused by this patch.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

It is always set to BUSSTATE_ON.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Rename ide_id_to_hd_driveid() to ata_id_to_hd_driveid()
and move it to <linux/ata.h>.

Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Factor out HDIO_{GET,SET}_NICE ioctl handling from
generic_ide_ioctl() to ide_{get,set}_nice_ioctl().
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Use drive->media and drive->scsi to check if ->dsc_overlap
  can be set by HDIO_SET_NICE ioctl in generic_ide_ioctl().

* Remove unused ->supports_dsc_overlap field from ide_driver_t.

There should be no functional changes caused by this patch.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

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

* Add struct ide_devset, S_* flags, *DEVSET() & ide*_devset_*() macros.

* Add 'const struct ide_devset **settings' to ide_driver_t.

* Use 'const struct ide_devset **settings' in ide_drive_t instead of
  'struct ide_settings_s *settings'.  Then convert core code and device
  drivers to use struct ide_devset and co.:

  - device settings are no longer allocated dynamically for each device
    but instead there is an unique struct ide_devset instance per setting

  - device driver keeps the pointer to the table of pointers to its
    settings in ide_driver_t.settings

  - generic settings are kept in ide_generic_setting[]

  - ide_proc_[un]register_driver(), ide_find_setting_by_name(),
    ide_{read,write}_setting() and proc_ide_{read,write}_settings()
    are updated accordingly

  - ide*_add_settings() are removed

* Remove no longer used __ide_add_setting(), ide_add_setting(),
  __ide_remove_setting() and auto_remove_settings().

* Remove no longer used TYPE_*, SETTING_*, ide_procset_t
  and ide_settings_t.

* ->keep_settings, ->using_dma, ->unmask, ->noflush, ->dsc_overlap,
  ->nice1, ->addressing, ->wcache and ->nowerr ide_drive_t fields
  can now be bitfield flags.

While at it:

* Rename ide_find_setting_by_name() to ide_find_setting().

* Rename write_wcache() to set_wcache().

There should be no functional changes caused by this patch.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

After rework settings will be no longer created dynamically
for each device so we need to make some fixups first.

* Use set_[ksettings,unmaskirq]() as a set function for
  ["keepsettings","unmaskirq"] setting.

* Allow writes to ["io_32bit","unmaskirq"] settings also when
  drive->no_[io_32bit,unmask] is set (this is checked later inside
  set_[io_32bit,unmaskirq]() anywyay and keeps consistency with
  the corresponding HDIO_SET_[32BIT,UNMASKINTR] ioctls).

* Use max possible multi sectors value (16) as an allowed max for
  "multcount" setting.  set_multcount() set function checks against
  device's max possbile value anyway and it makes the proc setting
  consistent with the corresponding HDIO_SET_MULTCOUNT ioctl.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Include <linux/ata.h> directly in <linux/ide.h>
  instead of through <linux/hdreg.h>.

* Include <linux/hdreg.h> only when needed.

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

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

* ERR_STAT   -> ATA_ERR
* INDEX_STAT -> ATA_IDX
* ECC_STAT   -> ATA_CORR
* DRQ_STAT   -> ATA_DRQ
* SEEK_STAT  -> ATA_DSC
* WRERR_STAT -> ATA_DF
* READY_STAT -> ATA_DRDY
* BUSY_STAT  -> ATA_BUSY

* MARK_ERR   -> ATA_AMNF
* TRK0_ERR   -> ATA_TRK0NF
* ABRT_ERR   -> ATA_ABORTED
* MCR_ERR    -> ATA_MCR
* ID_ERR     -> ATA_IDNF
* MC_ERR     -> ATA_MC
* ECC_ERR    -> ATA_UNC
* ICRC_ERR   -> ATA_ICRC

* BBD_ERR    -> ATA_BBK

Also:

* ILI_ERR    -> ATAPI_ILI
* EOM_ERR    -> ATAPI_EOM
* LFS_ERR    -> ATAPI_LFS

* CD         -> ATAPI_COD
* IO         -> ATAPI_IO
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Factor out HDIO_[OBSOLETE,GET]_IDENTITY ioctls handling
  to ide_get_identity_ioctl().

* Use temporary buffer in ide_get_identity_ioctl() instead
  of accessing drive->id directly.

* Add ide_id_to_hd_driveid() inline to convert raw id into
  struct hd_driveid format (needed on big-endian).

* Use ide_id_to_hd_driveid() in ide_get_identity_ioctl(),
  cleanup ide_fix_driveid() and switch ide to use use raw id.

* Remove no longer needed drive->driveid.

  This leaves us with 3 users of struct hd_driveid in tree:
  - arch/um/drivers/ubd_kern.c
  - drivers/block/xsysace.c
  - drivers/usb/storage/isd200.c

While at it:

* Use ata_id_u{32,64}() and ata_id_has_{dma,lba,iordy}() macros.

There should be no functional changes caused by this patch.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Make drive->id an unnamed union so id can be accessed either by using
'u16 *id' or 'struct hd_driveid *driveid'.  Then convert all existing
drive->id users accordingly (using 'u16 *id' when possible).

This is an intermediate step to make ide 'struct hd_driveid'-free.

While at it:

- Add missing KERN_CONTs in it821x.c.

- Use ATA_ID_WORDS and ATA_ID_*_LEN defines.

- Remove unnecessary checks for drive->id.

- s/drive_table/table/ in ide_in_drive_list().

- Cleanup ide_config_drive_speed() a bit.

- s/drive1/dev1/ & s/drive0/dev0/ in ide_undecoded_slave().

v2:
Fix typo in drivers/ide/ppc/pmac.c. (From Stephen Rothwell)

There should be no functional changes caused by this patch.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Add 'struct ide_host *host' field to ide_hwif_t and set it
  in ide_host_alloc_all().

* Add ide_device_{get,put}() helpers loosely based on SCSI's
  scsi_device_{get,put}() ones.

* Convert IDE device drivers to use ide_device_{get,put}().
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Small whitespace fixes for drivers/ide.
Signed-off-by: NPavel Machek <pavel@suse.cz>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Allocate ide_hwif_t instances dynamically and remove ide_hwifs[].

  This cuts almost ~14kB from ide-probe.o (x86-32, MAX_HWIFS == 10):

   text    data     bss     dec     hex filename
   9140      40   14084   23264    5ae0 drivers/ide/ide-probe.o.before
   9169      40      44    9253    2425 drivers/ide/ide-probe.o.after

* Remove no longer needed ide_init_port_data() call from ide_unregister().
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

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

* Add struct ide_host which keeps pointers to host's ports.

* Add ide_host_alloc[_all]() and ide_host_remove() helpers.

* Pass 'struct ide_host *host' instead of 'u8 *idx' to
  ide_device_add[_all]() and rename it to ide_host_register[_all]().

* Convert host drivers and core code to use struct ide_host.

* Remove no longer needed ide_find_port().

* Make ide_find_port_slot() static.

* Unexport ide_unregister().

v2:
* Add missing 'struct ide_host *host' to macide.c.

v3:
* Fix build problem in pmac.c (s/ide_alloc_host/ide_host_alloc/)
  (Noticed by Stephen Rothwell).
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Add struct ide_tp_ops for transport methods.

* Add 'const struct ide_tp_ops *tp_ops' to struct ide_port_info
  and ide_hwif_t.

* Set the default hwif->tp_ops in ide_init_port_data().

* Set host driver specific hwif->tp_ops in ide_init_port().

* Export ide_exec_command(), ide_read_status(), ide_read_altstatus(),
  ide_read_sff_dma_status(), ide_set_irq(), ide_tf_{load,read}()
  and ata_{in,out}put_data().

* Convert host drivers and core code to use struct ide_tp_ops.

* Remove no longer needed default_hwif_transport().

* Cleanup ide_hwif_t from methods that are now in struct ide_tp_ops.

While at it:

* Use struct ide_port_info in falconide.c and q40ide.c.

* Rename ata_{in,out}put_data() to ide_{in,out}put_data().

v2:

* Fix missing convertion in ns87415.c.

There should be no functional changes caused by this patch.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Add 'config' field to hw_regs_t and use it to set hwif->config_data in
ide_init_port_hw(), then convert ide_legacy_init_one() to use hw->config.

There should be no functional changes caused by this patch.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Remove no longer needed ->INB, ->OUTB and ->OUTBSYNC methods.

Then:

* Remove no longer used default_hwif_[mm]iops() and ide_[mm_]outbsync().

* Cleanup SuperIO handling in ns87415.c.

There should be no functional changes caused by this patch.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Add 'hw_regs_t **hws' argument to ide_device_add[_all]() and convert
  host drivers + ide_legacy_init_one() + ide_setup_pci_device[s]() to use
  it instead of calling ide_init_port_hw() directly.

  [ However if host has > 1 port we must still set hwif->chipset to hint
    consecutive ide_find_port() call that the previous slot is occupied. ]

* Unexport ide_init_port_hw().

v2:
* Use defines instead of hard-coded values in buddha.c, gayle.c and q40ide.c.
  (Suggested by Geert Uytterhoeven)

* Better patch description.

v3:
* Fix build problem in ide-cs.c. (Noticed by Stephen Rothwell)

There should be no functional changes caused by this patch.

Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Make sure that each error condition during the execution of an
HDIO_DRIVE_RESET ioctl is actually reported to the calling process.
Also, unify the exit path of reset_pollfunc() when returning ide_stopped
since the need of ->port_ops->reset_poll() to be treated specially has
vanished (way back, it seems).
Signed-off-by: NElias Oltmanns <eo@nebensachen.de>
Cc: "Alan Cox" <alan@lxorguk.ukuu.org.uk>
Cc: "Randy Dunlap" <randy.dunlap@oracle.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Currently, the code path executing an HDIO_DRIVE_RESET ioctl is broken
in various ways.  Most importantly, it is treated as an out of band
request in an illegal way which may very likely lead to system lock ups.
Use the drive's request queue to avoid this problem (and fix a locking
issue for free along the way).
Signed-off-by: NElias Oltmanns <eo@nebensachen.de>
Cc: "Alan Cox" <alan@lxorguk.ukuu.org.uk>
Cc: "Randy Dunlap" <randy.dunlap@oracle.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

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

* Add 'parent' field to hw_regs_t for optional parent device pointer (needed
  by macio PMAC IDE controllers) and set hwif->dev in ide_init_port_hw().

* Update au1xxx-ide.c, sgiioc4.c, pmac.c and setup-pci.c accordingly.

v2:

* Update scc_pata.c.

There should be no functional changes caused by this patch.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Move ide_hwifs[] from ide.c to ide-probe.c and make it static.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Add ide_hwifs[] entry initialization to ide_find_port_slot()
  and remove ide_init_port_data() calls from host drivers.

* Unexport ide_init_port_data().

* Remove no longer needed init_ide_data().
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>