Support "updatable groups".

* BOARD_SUPER_PARTITION_GROUPS defines a list of "updatable groups". Each
updatable group is a group of partitions that share the same pool of free
spaces.

* For each group in BOARD_SUPER_PARTITION_GROUPS, a BOARD_{GROUP}_SIZE and
BOARD_{GROUP}_PARTITION_PARTITION_LIST may be defined.
    - BOARD_{GROUP}_SIZE: The maximum sum of sizes of all
      partitions in the group.
      If empty, no limit is enforced on the sum of sizes for this group.
    - BOARD_{GROUP}_PARTITION_PARTITION_LIST: the list of partitions that
      belongs to this group.
      If empty, no partitions belong to this group, and the sum of sizes is
      effectively 0.

* BOARD_SUPER_PARTITION_PARTITION_LIST should not be defined
by the device. It is now computed from all
BOARD_{GROUP}_PARTITION_PARTITION_LIST.

* Each 'updatable group' has its own pool of space for its
partitions to grow into. Enforce the following:
    * sum(all partitions) <= super partition (/ 2 for A/B)
    * For each group, sum(partitions in group) <= group size
    * sum(all group sizes) <= super partition (/ 2 for A/B)

Test: builds
Bug: 111610495
Change-Id: I072b011714ec31a1d8813cc75edd27da3c6ff39a
Merged-In: I072b011714ec31a1d8813cc75edd27da3c6ff39a
3 files changed
tree: 7826651ef4d9f99d1fe3dc8d607b1f1c64abed2d
  1. core/
  2. target/
  3. tests/
  4. tools/
  5. .gitignore
  6. Android.mk
  7. buildspec.mk.default
  8. Changes.md
  9. CleanSpec.mk
  10. envsetup.sh
  11. help.sh
  12. navbar.md
  13. OWNERS
  14. README.md
  15. tapasHelp.sh
  16. Usage.txt
README.md

Android Make Build System

This is the Makefile-based portion of the Android Build System.

For documentation on how to run a build, see Usage.txt

For a list of behavioral changes useful for Android.mk writers see Changes.md

For an outdated reference on Android.mk files, see build-system.html. Our Android.mk files look similar, but are entirely different from the Android.mk files used by the NDK build system. When searching for documentation elsewhere, ensure that it is for the platform build system -- most are not.

This Makefile-based system is in the process of being replaced with Soong, a new build system written in Go. During the transition, all of these makefiles are read by Kati, and generate a ninja file instead of being executed directly. That's combined with a ninja file read by Soong so that the build graph of the two systems can be combined and run as one.