[PATCH v2 0/6] ATA PASS-THROUGH sense data fixes

[Igor Pylypiv <ipylypiv@google.com>]

This patch series is fixing a few ATA PASS-THROUGH issues:
1. Not reporting "ATA Status Return sense data descriptor" / "Fixed format
   sense data" when ATA_QCFLAG_SENSE_VALID is set.
2. Generating "fake" sk/asc/ascq based on ATA status/error registers when
   ATA_QCFLAG_SENSE_VALID is set and CK_COND=1.
3. Fixed format sense data was using incorrect field offsets for ATA
   PASS-THROUGH commands.
4. Using qc->result_tf in ATA sense data generation functions without
   checking if qc->result_tf contains a valid data.

Changes since v1:

Thanks Damien and Niklas for the reviews!

- Squashed two v1 patches 2/4 and 3/4 into one patch with a different
  implementation.
- Added 'Cc: stable@vger.kernel.org' tags to patches that are fixing bugs.
- Reordered patches with the 'Cc: stable@vger.kernel.org' tag to be applied
  first in order to simplify backports to stable releases.
- Restored the buffer memset in atapi_eh_request_sense().
- Updated declaration order in v1 patch 4/4.
- Added a patch to cleanup unused ATA device id in ata_to_sense_error().
- Updated fill_result_tf() to set ATA_QCFLAG_RTF_FILLED after populating
  the result taskfile. Removed now redundant flag sets/checks from ahci.
- Updated ATA sense data generation functions to return early if result_tf
  is not filled. Added WARN_ON_ONCE checks to generate a warning when
  ATA_QCFLAG_RTF_FILLED is not set and libata needs to generate sense data.

Igor Pylypiv (6):
  ata: libata-scsi: Do not overwrite valid sense data when CK_COND=1
  ata: libata-scsi: Fix offsets for the fixed format sense data
  ata: libata-scsi: Remove redundant sense_buffer memsets
  ata: libata-scsi: Do not pass ATA device id to ata_to_sense_error()
  ata: libata: Set ATA_QCFLAG_RTF_FILLED in fill_result_tf()
  ata: libata-scsi: Check ATA_QCFLAG_RTF_FILLED before using result_tf

 drivers/ata/libahci.c     |  10 ---
 drivers/ata/libata-core.c |   8 ++
 drivers/ata/libata-scsi.c | 179 +++++++++++++++++++++-----------------
 3 files changed, 107 insertions(+), 90 deletions(-)

-- 
2.45.2.741.gdbec12cfda-goog