dma-buf: heaps: Give default CMA heap a fixed name

The CMA heap's name in devtmpfs can vary depending on how the heap is
defined. Its name defaults to "reserved", but if a CMA area is defined
in the devicetree, the heap takes on the devicetree node's name, such as
"default-pool" or "linux,cma". To simplify naming, unconditionally name
it "default_cma_region", but keep a legacy node in place backed by the
same underlying allocator for backwards compatibility.

Reviewed-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Jared Kangas <jkangas@redhat.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://lore.kernel.org/r/20250610131231.1724627-4-jkangas@redhat.com
This commit is contained in:
Jared Kangas
2025-06-10 06:12:31 -07:00
committed by Sumit Semwal
parent 86e59cc506
commit 854acbe75f
3 changed files with 34 additions and 3 deletions

View File

@@ -21,5 +21,8 @@ following heaps:
usually created either through the kernel commandline through the
``cma`` parameter, a memory region Device-Tree node with the
``linux,cma-default`` property set, or through the ``CMA_SIZE_MBYTES`` or
``CMA_SIZE_PERCENTAGE`` Kconfig options. Depending on the platform, it
might be called ``reserved``, ``linux,cma``, or ``default-pool``.
``CMA_SIZE_PERCENTAGE`` Kconfig options. The heap's name in devtmpfs is
``default_cma_region``. For backwards compatibility, when the
``DMABUF_HEAPS_CMA_LEGACY`` Kconfig option is set, a duplicate node is
created following legacy naming conventions; the legacy name might be
``reserved``, ``linux,cma``, or ``default-pool``.