[RFC][PATCH 3/4] dma-buf: cma_heap: Extend logic to export CMA regions tagged with "linux,cma-heap"

From: John Stultz
Date: Fri May 01 2020 - 03:40:15 EST


This patch reworks the cma_heap initialization so that
we expose both the default CMA region and any CMA regions
tagged with "linux,cma-heap" in the device-tree.

Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx>
Cc: "Andrew F. Davis" <afd@xxxxxx>
Cc: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxx>
Cc: Liam Mark <lmark@xxxxxxxxxxxxxx>
Cc: Pratik Patel <pratikp@xxxxxxxxxxxxxx>
Cc: Laura Abbott <labbott@xxxxxxxxxx>
Cc: Brian Starkey <Brian.Starkey@xxxxxxx>
Cc: Chenbo Feng <fengc@xxxxxxxxxx>
Cc: Alistair Strachan <astrachan@xxxxxxxxxx>
Cc: Sandeep Patil <sspatil@xxxxxxxxxx>
Cc: Hridya Valsaraju <hridya@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Cc: Robin Murphy <robin.murphy@xxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: devicetree@xxxxxxxxxxxxxxx
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: linux-mm@xxxxxxxxx
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
---
drivers/dma-buf/heaps/cma_heap.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma-buf/heaps/cma_heap.c
index 626cf7fd033a..dd154e2db101 100644
--- a/drivers/dma-buf/heaps/cma_heap.c
+++ b/drivers/dma-buf/heaps/cma_heap.c
@@ -141,6 +141,11 @@ static int __add_cma_heap(struct cma *cma, void *data)
{
struct cma_heap *cma_heap;
struct dma_heap_export_info exp_info;
+ struct cma *default_cma = dev_get_cma_area(NULL);
+
+ /* We only add the default heap and explicitly tagged heaps */
+ if (cma != default_cma && !cma_dma_heap_enabled(cma))
+ return 0;

cma_heap = kzalloc(sizeof(*cma_heap), GFP_KERNEL);
if (!cma_heap)
@@ -162,16 +167,11 @@ static int __add_cma_heap(struct cma *cma, void *data)
return 0;
}

-static int add_default_cma_heap(void)
+static int cma_heaps_init(void)
{
- struct cma *default_cma = dev_get_cma_area(NULL);
- int ret = 0;
-
- if (default_cma)
- ret = __add_cma_heap(default_cma, NULL);
-
- return ret;
+ cma_for_each_area(__add_cma_heap, NULL);
+ return 0;
}
-module_init(add_default_cma_heap);
+module_init(cma_heaps_init);
MODULE_DESCRIPTION("DMA-BUF CMA Heap");
MODULE_LICENSE("GPL v2");
--
2.17.1