[PATCH v3 0/2] staging: ion: get one device per heap

From: Benjamin Gaignard
Date: Wed Sep 20 2017 - 04:45:23 EST

version 3:
- change ion_device_add_heap prototype to return a possible error

version 2:
- simplify ioctl check like propose by Dan
- make sure that we don't register more than ION_DEV_MAX heaps

Until now all ion heaps are addressing using the same device "/dev/ion".
This way of working doesn't allow to give access rights (for example with
SElinux rules) per heap.
This series propose to have one device "/dev/ionX" per heap.
Query heaps informations will be possible on each device node but allocation
request will only be possible if heap_mask_id match with device minor number.

That really change ion ABI because:
- device name change
- allocation must be done on the correct device/heap.
- device major number will not be the same and that could impact init scripts.

Even if splitting ion device in multiple node was one of the item of the
de-staging TODO list this must be agreed by a larger audience because it is
(again) an ion ABI bing bang. Hopefully that could be discussed at next XDC
to get a decission on this particular point.

Benjamin Gaignard (2):
staging: ion: simplify ioctl args checking function
staging: ion: create one device entry per heap

drivers/staging/android/TODO | 1 -
drivers/staging/android/ion/ion-ioctl.c | 20 +++++++++++++-------
drivers/staging/android/ion/ion.c | 27 ++++++++++++++++++++-------
drivers/staging/android/ion/ion.h | 12 ++++++++----
4 files changed, 41 insertions(+), 19 deletions(-)