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authorMarek Szyprowski <m.szyprowski@samsung.com>2026-03-31 13:31:53 +0200
committerMarek Szyprowski <m.szyprowski@samsung.com>2026-03-31 14:52:03 +0200
commit27e2e9b9b49c5d5260969168b86cd238254b9105 (patch)
tree360312000ffcb77b8d7078656821a18e13dc43f1 /kernel
parented734125ea6c7276aaac6e24b8fff72e51a47b18 (diff)
parent7e72a8f8bb0d5ba89027d64e3e2aad1984d2e20d (diff)
downloadlinux-27e2e9b9b49c5d5260969168b86cd238254b9105.tar.gz
linux-27e2e9b9b49c5d5260969168b86cd238254b9105.zip
Merge branch 'dma-contig-for-7.1-modules-prep-v4' into dma-mapping-for-next
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/dma/contiguous.c66
1 files changed, 60 insertions, 6 deletions
diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c
index 65d216663e81..03f52bd17120 100644
--- a/kernel/dma/contiguous.c
+++ b/kernel/dma/contiguous.c
@@ -42,7 +42,6 @@
#include <linux/memblock.h>
#include <linux/err.h>
#include <linux/sizes.h>
-#include <linux/dma-buf/heaps/cma.h>
#include <linux/dma-map-ops.h>
#include <linux/cma.h>
#include <linux/nospec.h>
@@ -53,7 +52,38 @@
#define CMA_SIZE_MBYTES 0
#endif
-struct cma *dma_contiguous_default_area;
+static struct cma *dma_contiguous_areas[MAX_CMA_AREAS];
+static unsigned int dma_contiguous_areas_num;
+
+static int dma_contiguous_insert_area(struct cma *cma)
+{
+ if (dma_contiguous_areas_num >= ARRAY_SIZE(dma_contiguous_areas))
+ return -EINVAL;
+
+ dma_contiguous_areas[dma_contiguous_areas_num++] = cma;
+
+ return 0;
+}
+
+/**
+ * dma_contiguous_get_area_by_idx() - Get contiguous area at given index
+ * @idx: index of the area we query
+ *
+ * Queries for the contiguous area located at index @idx.
+ *
+ * Returns:
+ * A pointer to the requested contiguous area, or NULL otherwise.
+ */
+struct cma *dma_contiguous_get_area_by_idx(unsigned int idx)
+{
+ if (idx >= dma_contiguous_areas_num)
+ return NULL;
+
+ return dma_contiguous_areas[idx];
+}
+EXPORT_SYMBOL_GPL(dma_contiguous_get_area_by_idx);
+
+static struct cma *dma_contiguous_default_area;
/*
* Default global CMA area size can be defined in kernel's .config.
@@ -91,6 +121,15 @@ static int __init early_cma(char *p)
}
early_param("cma", early_cma);
+struct cma *dev_get_cma_area(struct device *dev)
+{
+ if (dev && dev->cma_area)
+ return dev->cma_area;
+
+ return dma_contiguous_default_area;
+}
+EXPORT_SYMBOL_GPL(dev_get_cma_area);
+
#ifdef CONFIG_DMA_NUMA_CMA
static struct cma *dma_contiguous_numa_area[MAX_NUMNODES];
@@ -254,9 +293,24 @@ void __init dma_contiguous_reserve(phys_addr_t limit)
if (ret)
return;
- ret = dma_heap_cma_register_heap(dma_contiguous_default_area);
+ /*
+ * We need to insert the new area in our list to avoid
+ * any inconsistencies between having the default area
+ * listed in the DT or not.
+ *
+ * The DT case is handled by rmem_cma_setup() and will
+ * always insert all its areas in our list. However, if
+ * it didn't run (because OF_RESERVED_MEM isn't set, or
+ * there's no DT region specified), then we don't have a
+ * default area yet, and no area in our list.
+ *
+ * This block creates the default area in such a case,
+ * but we also need to insert it in our list to avoid
+ * having a default area but an empty list.
+ */
+ ret = dma_contiguous_insert_area(dma_contiguous_default_area);
if (ret)
- pr_warn("Couldn't register default CMA heap.");
+ pr_warn("Couldn't queue default CMA region for heap creation.");
}
}
@@ -529,9 +583,9 @@ static int __init rmem_cma_setup(unsigned long node, struct reserved_mem *rmem)
pr_info("Reserved memory: created CMA memory pool at %pa, size %ld MiB\n",
&rmem->base, (unsigned long)rmem->size / SZ_1M);
- ret = dma_heap_cma_register_heap(cma);
+ ret = dma_contiguous_insert_area(cma);
if (ret)
- pr_warn("Couldn't register CMA heap.");
+ pr_warn("Couldn't store CMA reserved area.");
return 0;
}