* Use blk_rq_bytes() instead of obsolete ide_rq_bytes() in ide_kill_rq()
  and ide_floppy_do_request() for failed requests.
  [ bugfix part ]

* Use blk_rq_bytes() instead of obsolete ide_rq_bytes() in ide_do_devset()
  and ide_complete_drive_reset().  Then remove ide_rq_bytes().
  [ cleanup part ]
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Unsupported requests should be never handed down to device drivers
and the best thing we can do upon discovering such request inside
driver's ->do_request method is to just BUG().
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Now after all users of pc->buf have been converted, remove the 64B buffer
embedded in each packet command.

There should be no functional change resulting from this patch.
Signed-off-by: NBorislav Petkov <petkovbb@gmail.com>

Access the sense buffer through the bio in ->pc_callback method thus
alleviating the need for the pc->buf pointer.

There should be no functional change resulting from this patch.
Signed-off-by: NBorislav Petkov <petkovbb@gmail.com>

There should be no functional change resulting from this patch.
Signed-off-by: NBorislav Petkov <petkovbb@gmail.com>

This is in preparation of removing ide_atapi_pc. Expose the buffer as an
argument to ide_queue_pc_tail with later replacing it with local buffer
or even kmalloc'ed one if needed due to stack usage constraints.

Also, add the possibility of passing a NULL-ptr buffer for cmds which
don't transfer data besides the cdb. While at it, switch to local buffer
in idetape_get_mode_sense_results().

There should be no functional change resulting from this patch.
Signed-off-by: NBorislav Petkov <petkovbb@gmail.com>

This is in preparation for removing ide_atapi_pc.

There should be no functional change resulting from this patch.
Signed-off-by: NBorislav Petkov <petkovbb@gmail.com>

After the recent struct request cleanups, blk_rq_bytes() is guaranteed
to be valid and is the current total length of the rq's bio. Use that
instead of pc->req_xfer in the do_request() path after the command has
been queued

The remaining usage of pc->req_xfer now is only until we map the rq to a
bio.

While at it:

- remove local caching of rq completion length in ide_tape_issue_pc()
Signed-off-by: NBorislav Petkov <petkovbb@gmail.com>

With recent unification of fields, it's now guaranteed that
rq->data_len always equals blk_rq_bytes().  Convert all direct users
to accessors.

[ Impact: convert direct rq->data_len usages to blk_rq_bytes() ]
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

ide doesn't manipulate request fields anymore and thus all hard and
their soft equivalents are always equal.  Convert all references to
accessors.

[ Impact: use pos and nr_sectors accessors ]
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Impact: allow residual count implementation in ->pc_callback()

rq->data_len has two duties - carrying the number of input bytes on
issue and carrying residual count back to the issuer on completion.
ide-atapi completion callback ->pc_callback() is the right place to do
this but currently ide-atapi depends on rq->data_len carrying the
original request size after calling ->pc_callback() to complete the pc
request.

This patch makes ide_pc_intr(), ide_tape_issue_pc() and
ide_floppy_issue_pc() cache length to complete before calling
->pc_callback() so that it can modify rq->data_len as necessary.

Note: As using rq->data_len for two purposes can make cases like this
      incorrect in subtle ways, future changes will introduce separate
      field for residual count.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Jens Axboe <jens.axboe@oracle.com>

Impact: fix infinite retry loop

After a command failed, ide-tape and floppy inserts REQUEST_SENSE in
front of the failed command and according to the result, sets
pc->retries, flags and errors.  After REQUEST_SENSE is complete, the
failed command is again at the front of the queue and if the verdict
was to terminate the request, the issue functions tries to complete it
directly by calling drive->pc_callback() and returning ide_stopped.

However, drive->pc_callback() doesn't complete a request.  It only
prepares for completion of the request.  As a result, this creates an
infinite loop where the failed request is retried perpetually.

Fix it by actually ending the request by calling ide_complete_rq().
Signed-off-by: NTejun Heo <tj@kernel.org>

Since we're issuing REQ_TYPE_SENSE now we need to allow those types of
rqs in the ->do_request callbacks. As a future improvement, sense_len
assignment might be unified across all ATAPI devices. Borislav to
check with specs and test.

As a result, get rid of ide_queue_pc_head() and
drive->request_sense_rq.

tj: * Init request sense ide_atapi_pc from sense request.  In the
      longer timer, it would probably better to fold
      ide_create_request_sense_cmd() into its only current user -
      ide_floppy_get_format_progress().

    * ide_retry_pc() no longer takes @disk.

CC: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
CC: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NBorislav Petkov <petkovbb@gmail.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

Impact: rq->buffer usage cleanup

ide-atapi uses rq->buffer as private opaque value for internal special
requests.  rq->special isn't used for these cases (the only case where
rq->special is used is for ide-tape rw requests).  Use rq->special
instead.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>

Impact: remove unnecessary code path

Block pc requests always use bio and rq->data is always NULL.  No need
to worry about !rq->bio cases in idefloppy_block_pc_cmd().  Note that
ide-atapi uses ide_pio_bytes() for bio PIO transfer which handle sg
fine.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>

Impact: allow residual count implementation in ->pc_callback()

rq->data_len has two duties - carrying the number of input bytes on
issue and carrying residual count back to the issuer on completion.
ide-atapi completion callback ->pc_callback() is the right place to do
this but currently ide-atapi depends on rq->data_len carrying the
original request size after calling ->pc_callback() to complete the pc
request.

This patch makes ide_pc_intr(), ide_tape_issue_pc() and
ide_floppy_issue_pc() cache length to complete before calling
->pc_callback() so that it can modify rq->data_len as necessary.

Note: As using rq->data_len for two purposes can make cases like this
      incorrect in subtle ways, future changes will introduce separate
      field for residual count.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Jens Axboe <jens.axboe@oracle.com>

Impact: fix infinite retry loop

After a command failed, ide-tape and floppy inserts REQUEST_SENSE in
front of the failed command and according to the result, sets
pc->retries, flags and errors.  After REQUEST_SENSE is complete, the
failed command is again at the front of the queue and if the verdict
was to terminate the request, the issue functions tries to complete it
directly by calling drive->pc_callback() and returning ide_stopped.

However, drive->pc_callback() doesn't complete a request.  It only
prepares for completion of the request.  As a result, this creates an
infinite loop where the failed request is retried perpetually.

Fix it by actually ending the request by calling ide_complete_rq().
Signed-off-by: NTejun Heo <tj@kernel.org>

Since we're issuing REQ_TYPE_SENSE now we need to allow those types of
rqs in the ->do_request callbacks. As a future improvement, sense_len
assignment might be unified across all ATAPI devices. Borislav to
check with specs and test.

As a result, get rid of ide_queue_pc_head() and
drive->request_sense_rq.

tj: * Init request sense ide_atapi_pc from sense request.  In the
      longer timer, it would probably better to fold
      ide_create_request_sense_cmd() into its only current user -
      ide_floppy_get_format_progress().

    * ide_retry_pc() no longer takes @disk.

CC: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
CC: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NBorislav Petkov <petkovbb@gmail.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

Impact: rq->buffer usage cleanup

ide-atapi uses rq->buffer as private opaque value for internal special
requests.  rq->special isn't used for these cases (the only case where
rq->special is used is for ide-tape rw requests).  Use rq->special
instead.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>

Impact: remove unnecessary code path

Block pc requests always use bio and rq->data is always NULL.  No need
to worry about !rq->bio cases in idefloppy_block_pc_cmd().  Note that
ide-atapi uses ide_pio_bytes() for bio PIO transfer which handle sg
fine.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>

* Fix ide_init_sg_cmd() setup for non-fs requests.

* Convert ide_pc_intr() to use ide_pio_bytes() for floppy media.

* Remove no longer needed ide_io_buffers() and sg/sg_cnt fields
  from struct ide_atapi_pc.

* Remove partial completions; kill idefloppy_update_buffers(), as a
  result.

* Add some more debugging statements.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: NBorislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

struct ide_atapi_pc is often allocated on the stack and size of ->pc_buf
size is 256 bytes.  However since only ide_floppy_create_read_capacity_cmd()
and idetape_create_inquiry_cmd() require such size allocate buffers for
these pc-s explicitely and decrease ->pc_buf size to 64 bytes.

Cc: Borislav Petkov <petkovbb@gmail.com>
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 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>

There should be no functional changes caused by this patch.
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>

Set rq->errors at ide_complete_rq() call sites and then pass
error value to ide_complete_rq().

[ Some rq->errors assignments look really wrong but this patch
  leaves them alone to not introduce too many changes at once. ]

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

* Move command related fields from ide_hwif_t to struct ide_cmd.

* Make ide_init_sg_cmd() take command and sectors number as arguments.

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

Make ->pc_callback method return request status and then move
the request completion from ->pc_callback to ide_pc_intr().

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>

* Handle completion of private driver requests explicitly
  for ide_floppy and ide_tape media in ide_kill_rq().

* Remove no longer needed ->end_request method.

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>

* ide*_end_request() is only called with uptodate == 0 or uptodate == 1
  so cleanup it accordingly.

* Inline ide*_end_request() content at call sites so the only user left
  is ->end_request method.

* ->end_request is now used only for private driver requests so remove
  handling of other requests from ide*_end_request().

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>

* Move IDE{FLOPPY,TAPE}_ERROR_* defines to <linux/ide.h> and rename them
  to IDE_DRV_ERROR_*.

* Handle ->end_request special cases for floppy/tape media in ide_kill_rq().

* Call ->end_request only for private device driver requests.

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>

Move ->failed_pc from struct ide_{disk,tape}_obj to ide_drive_t.

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>

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>

* Move request type specific code from ide_end_drive_cmd() to callers.

* Remove stale ide_end_drive_cmd() documentation and drop no longer
  used 'stat' argument.  Then rename the function to ide_complete_rq().

v2:
* Fix handling of blk_pm_request() requests in task_no_data_intr().

v3:
* Some ide_no_data_taskfile() users (HPA code and HDIO_DRIVE_* ioctls
  handlers) access original command later so we need to update it in
  ide_complete_task().

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

and more specifically, push __func__ into debug
macro thus making ide_debug_log() calls shorter and more readable.
Signed-off-by: NBorislav Petkov <petkovbb@gmail.com>

since it fails the virt_to_page() translation check with DEBUG_VIRTUAL
enabled.
Signed-off-by: NBorislav Petkov <petkovbb@gmail.com>
[bart: backport to Linus' tree]
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Merge ide_hwgroup_t with ide_hwif_t.

* Cleanup init_irq() accordingly, then remove no longer needed
  ide_remove_port_from_hwgroup() and ide_ports[].

* Remove now unused HWGROUP() macro.

While at it:

* ide_dump_ata_error() fixups

v2:
* Fix ->quirk_list check in do_ide_request()
  (s/hwif->cur_dev/prev_port->cur_dev).
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>