cgpt: Split fs_block_size, add fs_align

I want my larger partitions to be aligned to a bit more than just
the underlying block size. This allows chromeos-install to copy
things faster, especially when installing from a USB stick with
small sectors to a UFS disk with larger sectors. Unfortunately,
I can't just set a gigantic fs_block_size, because that makes its
way into mkfs.

Split fs_block_size into fs_block_size and fs_align. Now fs_align
can be specified separately, and will be used when aligning
file-system partitions. If not specified (which would be all boards
today), then it defaults to fs_block_size, so there should be no
behavior change for existing layouts.

BUG=None
TEST=build_image, boot the USB stick, chromeos-install onto cheza UFS

Change-Id: I149d2f0b025a9a5d961a9bfbda1e7297f709aca6
Reviewed-on: https://chromium-review.googlesource.com/1299715
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: Evan Green <evgreen@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
1 file changed