[PATCHv3 0/5] FWU: Handle meta-data in common code

[Jassi Brar]

The patchset reduces ~400 lines of code, while keeping the functionality same and making
meta-data operations much faster (by using cached structures).

Issue:
 meta-data copies (primary and secondary) are being handled by the backend/storage layer
instead of the common core in fwu.c (as also noted by Ilias)  that is, gpt_blk.c manages
meta-data and similarly raw_mtd.c will have to do the same when it arrives. The code
could by make smaller, cleaner and optimised.

Basic idea:
 Introduce  .read_mdata() and .write_mdata() in fwu_mdata_ops  that simply read/write
meta-data copy. The core code takes care of integrity and redundancy of the meta-data,
as a result we can get rid of every other callback .get_mdata() .update_mdata()
.get_mdata_part_num()  .read_mdata_partition()  .write_mdata_partition() and the
corresponding wrapper functions thereby making the code 100s of LOC smaller.

Get rid of fwu_check_mdata_validity() and fwu_mdata_check() which expected underlying
layer to manage and verify mdata copies.
Implement  fwu_get_verified_mdata(struct fwu_mdata *mdata) public function that reads,
verifies and, if needed, fixes the meta-data copies.

Verified copy of meta-data is now cached as 'g_mdata' in fwu.c, which avoids multiple
low-level expensive read and parse calls.
gpt meta-data partition numbers are now cached in gpt_blk.c, so that we don't have to do expensive part_get_info() and uid ops.

Changes since v2:
        * Drop whitespace changes
        * Fix missing mdata copy before return

Changes since v1:
        * Fix typos and misc cosmetic changes
        * Catch error returns


Jassi Brar (5):
  fwu: gpt: use cached meta-data partition numbers
  fwu: move meta-data management in core
  fwu: gpt: implement read_mdata and write_mdata callbacks
  fwu: meta-data: switch to management by common code
  fwu: rename fwu_get_verified_mdata to fwu_get_mdata

 cmd/fwu_mdata.c                      |  17 +-
 drivers/fwu-mdata/fwu-mdata-uclass.c | 151 +-------------
 drivers/fwu-mdata/gpt_blk.c          | 175 +++++-----------
 include/fwu.h                        | 198 ++----------------
 lib/fwu_updates/fwu.c                | 301 ++++++++++++---------------
 5 files changed, 214 insertions(+), 628 deletions(-)

-- 
2.34.1