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>

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

- cdrom_timer_expiry -> ide_cd_expiry
- remove expiry-arg to ide_issue_pc as it is redundant now
- ide_debug_log -> debug_log
Signed-off-by: NBorislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

This makes the top-level function just allocate a single pc entry, and then
pass it down as a pointer to all the helper functions that also need one
of those "struct ide_atapi_pc" things. As far as I can tell, the use of
these things never overlaps each other, BUT I DID NOT CHECK VERY CLOSELY!

So I'm not guaranteeing this is correct, and I don't have the hardware. It
would be good for somebody who knows the code more, and has the hardware,
could please test this?

With this, ide-floppy still has fairly big stack usage, but instead of

	idefloppy_ioctl [vmlinux]:              1208
	ide_floppy_get_capacity [vmlinux]:      872
	idefloppy_release [vmlinux]:            408
	idefloppy_open [vmlinux]:               408

where those two first ones are at the very top of the list of stack users
for me, it's now

	ide_floppy_get_capacity [vmlinux]:           404
	ide_floppy_ioctl [vmlinux]:                  364

ie they are still high, but they are no longer at the top.

Borislav: Since ide_floppy_get_capacity is passed as a function pointer to other
parts of the kernel (e.g., block layer) we need that ide_atapi_pc to be created
on stack. Also, redid stack users numbers above. The two functions missing from
Linus' original 'make stackusage' output are due to ide being
rewritten/reorganized atm.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-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>
Acked-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Add struct ide_disk_ops containing protocol specific methods.

* Add 'struct ide_disk_ops *' to ide_drive_t.

* Convert ide-{disk,floppy} drivers to use struct ide_disk_ops.

* Merge ide-{disk,floppy} drivers into generic ide-gd driver.

While at it:
- ide_disk_init_capacity() -> ide_disk_get_capacity()
Acked-by: NBorislav Petkov <petkovbb@gmail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

While at it:
- idefloppy_do_request() -> ide_floppy_do_request()
- idefloppy_end_request() -> ide_floppy_end_request()
- idefloppy_setup() -> ide_floppy_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>

Just use IDE_DFLAG_DOORLOCKING instead.

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>

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>

* Use drive->capacity64 for caching current capacity.

* Switch ide_floppy_capacity() to use drive->capacity64.

* Call set_capacity() in idefloppy_open() and ide_floppy_probe()
  instead of ide_floppy_get_capacity().

There should be no functional changes caused by this patch.

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

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>

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

While at it:
- idefloppy_capacity() -> ide_floppy_capacity()
- idefloppy_proc[] -> ide_floppy_proc[]
- idefloppy_settings[] -> ide_floppy_settings[]

v2:
Build fix for CONFIG_IDE_PROC_FS=n from Elias Oltmanns.

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

While at it:
- idefloppy_ioctl() -> ide_floppy_ioctl()

v2:
Fix for idefloppy_ioctl name change from Stephen Rothwell.

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

Set IDE_AFLAG_DRQ_INTERRUPT in do_identify() instead of ATAPI
device drivers *_setup() methods.

While at it:
- use ata_id_cdb_intr()

There should be no functional changes caused by this patch.

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

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