1 files changed, 115 insertions, 29 deletions

diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c
index c56004d314dc..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.
@@ -91,15 +121,14 @@ static int __init early_cma(char *p)
 }
 early_param("cma", early_cma);
 
-/*
- * cma_skip_dt_default_reserved_mem - This is called from the
- * reserved_mem framework to detect if the default cma region is being
- * set by the "cma=" kernel parameter.
- */
-bool __init cma_skip_dt_default_reserved_mem(void)
+struct cma *dev_get_cma_area(struct device *dev)
 {
-	return size_cmdline != -1;
+	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
 
@@ -264,9 +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.");
 	}
 }
 
@@ -470,47 +514,89 @@ static void rmem_cma_device_release(struct reserved_mem *rmem,
 	dev->cma_area = NULL;
 }
 
-static const struct reserved_mem_ops rmem_cma_ops = {
-	.device_init	= rmem_cma_device_init,
-	.device_release = rmem_cma_device_release,
-};
+static int __init __rmem_cma_verify_node(unsigned long node)
+{
+	if (!of_get_flat_dt_prop(node, "reusable", NULL) ||
+	    of_get_flat_dt_prop(node, "no-map", NULL))
+		return -ENODEV;
+
+	if (size_cmdline != -1 &&
+	    of_get_flat_dt_prop(node, "linux,cma-default", NULL)) {
+		pr_err("Skipping dt linux,cma-default node in favor for \"cma=\" kernel param.\n");
+		return -EBUSY;
+	}
+	return 0;
+}
 
-static int __init rmem_cma_setup(struct reserved_mem *rmem)
+static int __init rmem_cma_validate(unsigned long node, phys_addr_t *align)
+{
+	int ret = __rmem_cma_verify_node(node);
+
+	if (ret)
+		return ret;
+
+	if (align)
+		*align = max_t(phys_addr_t, *align, CMA_MIN_ALIGNMENT_BYTES);
+
+	return 0;
+}
+
+static int __init rmem_cma_fixup(unsigned long node, phys_addr_t base,
+				    phys_addr_t size)
+{
+	int ret = __rmem_cma_verify_node(node);
+
+	if (ret)
+		return ret;
+
+	/* Architecture specific contiguous memory fixup. */
+	dma_contiguous_early_fixup(base, size);
+	return 0;
+}
+
+static int __init rmem_cma_setup(unsigned long node, struct reserved_mem *rmem)
 {
-	unsigned long node = rmem->fdt_node;
 	bool default_cma = of_get_flat_dt_prop(node, "linux,cma-default", NULL);
 	struct cma *cma;
-	int err;
+	int ret;
 
-	if (!of_get_flat_dt_prop(node, "reusable", NULL) ||
-	    of_get_flat_dt_prop(node, "no-map", NULL))
-		return -EINVAL;
+	ret = __rmem_cma_verify_node(node);
+	if (ret)
+		return ret;
 
 	if (!IS_ALIGNED(rmem->base | rmem->size, CMA_MIN_ALIGNMENT_BYTES)) {
 		pr_err("Reserved memory: incorrect alignment of CMA region\n");
 		return -EINVAL;
 	}
 
-	err = cma_init_reserved_mem(rmem->base, rmem->size, 0, rmem->name, &cma);
-	if (err) {
+	ret = cma_init_reserved_mem(rmem->base, rmem->size, 0, rmem->name, &cma);
+	if (ret) {
 		pr_err("Reserved memory: unable to setup CMA region\n");
-		return err;
+		return ret;
 	}
 
 	if (default_cma)
 		dma_contiguous_default_area = cma;
 
-	rmem->ops = &rmem_cma_ops;
 	rmem->priv = cma;
 
 	pr_info("Reserved memory: created CMA memory pool at %pa, size %ld MiB\n",
 		&rmem->base, (unsigned long)rmem->size / SZ_1M);
 
-	err = dma_heap_cma_register_heap(cma);
-	if (err)
-		pr_warn("Couldn't register CMA heap.");
+	ret = dma_contiguous_insert_area(cma);
+	if (ret)
+		pr_warn("Couldn't store CMA reserved area.");
 
 	return 0;
 }
-RESERVEDMEM_OF_DECLARE(cma, "shared-dma-pool", rmem_cma_setup);
+
+static const struct reserved_mem_ops rmem_cma_ops = {
+	.node_validate  = rmem_cma_validate,
+	.node_fixup	= rmem_cma_fixup,
+	.node_init	= rmem_cma_setup,
+	.device_init	= rmem_cma_device_init,
+	.device_release = rmem_cma_device_release,
+};
+
+RESERVEDMEM_OF_DECLARE(cma, "shared-dma-pool", &rmem_cma_ops);
 #endif