* Add ide_dma_prepare() helper.

* Convert ide_issue_pc() and do_rw_taskfile() to use it.

* Make ide_build_sglist() static.

There should be no functional changes caused by this patch.
Acked-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Move ide_destroy_dmatable() call out from ->dma_end method to
{ide_pc,cdrom_newpc,ide_dma}_intr(), ide_dma_timeout_retry()
and sgiioc4_resetproc().

This causes minor/safe behavior changes w.r.t.:
* cmd64x.c::cmd64{8,x}_dma_end()
* cs5536.c::cs5536_dma_end()
* icside.c::icside_dma_end()
* it821x.c::it821x_dma_end()
* scc_pata.c::__scc_dma_end()
* sl82c105.c::sl82c105_dma_end()
* tx4939ide.c::tx4939ide_dma_end()

v2:
* Fix build for CONFIG_BLK_DEV_IDEDMA=n (reported by Randy Dunlap).

Cc: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Since ide_dma_timeout() is only used by ide_dma_timeout_retry()
inline it there.

There should be no functional changes caused by this patch.
Acked-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

All custom ->dma_timeout implementations call the generic one thus it is
possible to have only an optional method for resetting DMA engine instead:

* Add ->dma_clear method and convert hpt366, pdc202xx_old and sl82c105
  host drivers to use it.

* Always use ide_dma_timeout() in ide_dma_timeout_retry() and remove
 ->dma_timeout method.

* Make ide_dma_timeout() static.

There should be no functional changes caused by this patch.
Acked-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Cache drive->queue in local variable and use max().

There should be no functional changes caused by this patch.
Acked-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Acked-by: NBorislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* 'thislen' is always <= cmd->nleft for non-fs requests so the transfer
  padding inside the 'while (thislen > 0)' loop can happen only for fs
  requests -- then move it out of the loop and unify with the transfer
  padding for non-fs requests ('thislen' == 'len' for fs requests).

* blk_dump_rq_flags() dumps all request flags so it is enough to pass
  only the function name to it.

* Update my Copyrights while at it.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Use the following facts:

- rq->nr_sectors should now be always equal to (non-zero)
  rq->hard_nr_sectors for fs requests

- REQ_TYPE_ATA_PC requests have never bio attached to them

- rq->hard_nr_sectors == 0 for REQ_TYPE_ATA_PC requests

- DMA is used only for fs, pc and REQ_TYPE_ATA_PC requests

- 'uptodate' is ignored for pc requests ('rc == 0' case)

and use the common completion path also for DMA requests.

There should be no functional changes caused by this patch

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Convert ide-cd to use scatterlists for PIO transfers and get rid of
partial completions (except on error) also for non-fs requests.

v2:
Do not map dataless commands to an sg since it oopses on the virt_to_page()
translation check when DEBUG_VIRTUAL is enabled.  (from Borislav Petkov,
reported/bisected-by Tetsuo Handa).

Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: NBorislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

There should be no functional changes caused by this patch.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

We now support arbitrary number of bytes per-IRQ also for fs requests
so remove ide_cd_check_transfer_size() and IDE_AFLAG_LIMIT_NFRAMES.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Export ide_pio_bytes().

* Add ->last_xfer_len field to struct ide_cmd.

* Add ide_cd_error_cmd() helper to ide-cd.

* Convert ide-cd to use scatterlists also for PIO transfers (fs requests
  only for now) and get rid of partial completions (except when the error
  happens -- which is still subject to change later because looking at
  ATAPI spec it seems that the device is free to error the whole transfer
  with setting the Error bit only on the last transfer chunk).

* Update ide_cd_{prepare_rw,restore_request,do_request}() accordingly.

* Inline ide_cd_restore_request() into cdrom_start_rw().

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

There should be no functional changes caused by this patch.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Untangling cdrom_end_request() uncovered an error in completing
failed requests in ide_cd_do_request().  Fix it.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Inline cdrom_end_request() into cdrom_newpc_intr()
and ide_cd_do_request().

There should be no functional changes caused by this patch.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Move cdrom_end_request() calls from cdrom_decode_status()
  and ide_cd_check_ireason() to cdrom_newpc_intr().

* Unify cdrom_newpc_intr() exit paths.

There should be no functional changes caused by this patch.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Move setting REQ_FAILED flag out from 'end_request' exit path in
cdrom_newpc_intr() and also rename 'end_request' to 'out_end'.

There should be no functional changes caused by this patch.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Move cdrom_end_request() calls from cdrom_start_rw()
  and ide_cd_prepare_rw_request() to ide_cd_do_request().

* Unify ide_cd_do_request() exit paths.

There should be no functional changes caused by this patch.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

There should be no functional changes caused by this patch.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

ide-scsi is gone...

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

It makes no sense to check for BSY bit being set as earlier OK_STAT()
check in cdrom_end_request() makes sure that BSY bit is cleared.

There should be no functional changes caused by this patch.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

There should be no functional changes caused by this patch.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Use ide_end_rq() also for failed non-fs requests on completion
of REQUEST SENSE requests + use blk_rq_bytes() while at it.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Use PageHighMem() instead of ifdefs in ide_pio_bytes()
(=> local IRQs won't be disabled when not necessary).

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Add support for arbitrary transfer lengths to ide_pio_bytes()
and then inline ide_pio_multi() into ide_pio_datablock().

There should be no functional changes caused by this patch.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Apparently¹, some ATAPI devices want to see the packet command first
before enabling DMA otherwise they simply hang indefinitely. Reorder the
two steps and start DMA only after having issued the command first.

[1] http://marc.info/?l=linux-kernel&m=123835520317235&w=2Signed-off-by: NBorislav Petkov <petkovbb@gmail.com>
Reported-by: NMichael Roth <mroth@nessie.de>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Fix some incorrect IDE_FTFLAG_* changes which slipped in commit
"ide: add "flagged" taskfile flags to struct ide_taskfile (v2)"
(commit 19710d25) few days ago.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

On m68k:
| drivers/ide/ide-atapi.c: In function 'ide_io_buffers':
| drivers/ide/ide-atapi.c:87: error: implicit declaration of function 'sg_page'
| drivers/ide/ide-atapi.c:87: warning: passing argument 1 of 'PageHighMem' makes pointer from integer without a cast
| drivers/ide/ide-atapi.c:91: warning: passing argument 1 of 'kmap_atomic' makes pointer from integer without a cast
| drivers/ide/ide-atapi.c:96: error: implicit declaration of function 'sg_virt'
| drivers/ide/ide-atapi.c:96: warning: assignment makes pointer from integer without a cast
| drivers/ide/ide-atapi.c:107: error: implicit declaration of function 'sg_next'
| drivers/ide/ide-atapi.c:107: warning: assignment makes pointer from integer without a cast

[bart: Dmitri Vorobiev submitted similar patch fixing MIPS]
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Cc: Dmitri Vorobiev <dmitri.vorobiev@movial.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Unfortunately, I missed a catch when reviewing the patch committed as
201bffa4. Here is the fix to the currently broken handling of sleeping
devices. In particular, this is required to get the disk shock
protection code working again.
Reported-by: NChristian Thaeter <ct@pipapo.org>
Cc: stable@kernel.org
Signed-off-by: NElias Oltmanns <eo@nebensachen.de>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Pass number of bytes instead of sectors to ide_init_sg_cmd().

* Pass number of bytes to process to ide_pio_sector() and rename
  it to ide_pio_bytes().

* Rename ->nsect field to ->nbytes in struct ide_cmd and use
  ->nbytes, ->nleft and ->cursg_ofs to keep track of number of
  bytes instead of sectors.

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

* Pass command structure to ide_execute_command() and skip
  __ide_set_handler() for ATAPI protocols on non-DRQ devices.

* Convert ide_issue_pc() to always use ide_execute_command()
  and remove no longer needed ide_execute_pkt_cmd().

v2:
* Fix for non-DRQ devices (based on report from Borislav).

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

* Rename dma_timer_expiry() to ide_dma_sff_timer_expiry() and export it.

* Add ->dma_timer_expiry method and use it to set hwif->expiry for
  ATA_PROT_DMA protocol in do_rw_taskfile().

* Initialize ->dma_timer_expiry to ide_dma_sff_timer_expiry() for SFF hosts.

* Move setting hwif->expiry from ide_execute_command() to its users and drop
  'expiry' argument.

* Use ide_execute_command() instead of ->dma_exec_cmd in do_rw_taskfile().

* Remove ->dma_exec_cmd method and its implementations.

* Unexport ide_execute_command() and ide_dma_intr().

v2:
* Fix CONFIG_BLK_DEV_IDEDMA=n build (noticed by Randy Dunlap).

* Fix *dma_expiry naming (suggested by Sergei Shtylyov).

There should be no functional changes caused by this patch.

Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Set hwif->expiry prior to calling [__]ide_set_handler()
  and drop 'expiry' argument.

* Set hwif->expiry to NULL in ide_{timer_expiry,intr}()
  and remove 'hwif->expiry = NULL' assignments.

There should be no functional changes caused by this patch.
Acked-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Pass command to ide_issue_pc() and update ->do_request methods
  in ide-{cd,floppy,tape}.c accordingly.

* Convert ide_pktcmd_tf_load() to ide_init_packet_cmd() which
  just initializes command structure and use do_rw_taskfile()
  to load ATA_CMD_PACKET commands.

While at it:

* Rename ide{floppy,tape}_issue_pc() to ide_{floppy,tape}_issue_pc().

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

* Set IDE_TFLAG_WRITE flag and ->rq also for ATA_CMD_PACKET
  commands.

* Pass command to ->dma_setup method and update all its
  implementations accordingly.

* Pass command instead of request to ide_build_sglist(),
  *_build_dmatable() and ide_map_sg().

While at it:

* Fix scc_dma_setup() documentation + use ATA_DMA_WR define.

* Rename sgiioc4_build_dma_table() to sgiioc4_build_dmatable(),
  change return value type to 'int' and drop unused 'ddir'
  argument.

* Do some minor cleanups in [tx4939]ide_dma_setup().

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

* Add ide_rq_bytes() helper.

* Add blk_noretry_request() quirk to ide_complete_rq() (currently only fs
  requests can be marked as "noretry" so there is no change in behavior).

* Switch current ide_end_request() users to use ide_complete_rq().

  [ No need to check for rq->nr_sectors == 0 in {ide_dma,task_pio}_intr(),
    nsectors == 0 in cdrom_end_request() and err == 0 in ide_do_devset(). ]

* Remove no longer needed ide_end_request().

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

This results in PIO->DMA retry being triggered also on completion
of requests using ide_complete_rq() instead of ide_end_request().
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

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

It is no longer needed so remove it, also while at it dequeue the request
only on blk_end_request() success and make ide_complete_rq() return an error
value.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Move rq->errors quirk out from ide_end_request() to its call sites.

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