[v5,9/9] dma_buf: heaps: restricted_heap_mtk: Add a new CMA heap

Message ID 20240515112308.10171-10-yong.wu@mediatek.com (mailing list archive)
State New
Headers
Series dma-buf: heaps: Add restricted heap |

Commit Message

Yong Wu May 15, 2024, 11:23 a.m. UTC
  Create a new MediaTek CMA heap from the CMA reserved buffer.

In this heap, When the first allocating buffer, use cma_alloc to prepare
whole the CMA range, then send its range to TEE to protect and manage.
For the later allocating, we just adds the cma_used_size.

When SVP done, cma_release will release the buffer, then kernel may
reuse it.

For the "CMA" restricted heap, "struct cma *cma" is a common property,
not just for MediaTek, so put it into "struct restricted_heap" instead of
our private data.

Signed-off-by: Yong Wu <yong.wu@mediatek.com>
---
 drivers/dma-buf/heaps/Kconfig               |   2 +-
 drivers/dma-buf/heaps/restricted_heap.h     |   4 +
 drivers/dma-buf/heaps/restricted_heap_mtk.c | 121 +++++++++++++++++++-
 3 files changed, 123 insertions(+), 4 deletions(-)
  

Patch

diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma-buf/heaps/Kconfig
index 84f748fb2856..58903bc62ac8 100644
--- a/drivers/dma-buf/heaps/Kconfig
+++ b/drivers/dma-buf/heaps/Kconfig
@@ -24,7 +24,7 @@  config DMABUF_HEAPS_RESTRICTED
 
 config DMABUF_HEAPS_RESTRICTED_MTK
 	bool "MediaTek DMA-BUF Restricted Heap"
-	depends on DMABUF_HEAPS_RESTRICTED && TEE=y
+	depends on DMABUF_HEAPS_RESTRICTED && DMA_CMA && TEE=y
 	help
 	  Enable restricted dma-buf heaps for MediaTek platform. This heap is backed by
 	  TEE client interfaces. If in doubt, say N.
diff --git a/drivers/dma-buf/heaps/restricted_heap.h b/drivers/dma-buf/heaps/restricted_heap.h
index 8cb9211093c5..7dec4b8a471b 100644
--- a/drivers/dma-buf/heaps/restricted_heap.h
+++ b/drivers/dma-buf/heaps/restricted_heap.h
@@ -23,6 +23,10 @@  struct restricted_heap {
 
 	const struct restricted_heap_ops *ops;
 
+	struct cma		*cma;
+	unsigned long		cma_paddr;
+	unsigned long		cma_size;
+
 	void			*priv_data;
 };
 
diff --git a/drivers/dma-buf/heaps/restricted_heap_mtk.c b/drivers/dma-buf/heaps/restricted_heap_mtk.c
index e571eae719e0..6d8119828485 100644
--- a/drivers/dma-buf/heaps/restricted_heap_mtk.c
+++ b/drivers/dma-buf/heaps/restricted_heap_mtk.c
@@ -6,9 +6,11 @@ 
  */
 #define pr_fmt(fmt)     "rheap_mtk: " fmt
 
+#include <linux/cma.h>
 #include <linux/dma-buf.h>
 #include <linux/err.h>
 #include <linux/module.h>
+#include <linux/of_reserved_mem.h>
 #include <linux/slab.h>
 #include <linux/tee_drv.h>
 #include <linux/uuid.h>
@@ -25,6 +27,13 @@  enum mtk_secure_mem_type {
 	 * management is inside the TEE.
 	 */
 	MTK_SECURE_MEMORY_TYPE_CM_TZ	= 1,
+	/*
+	 * MediaTek dynamic chunk memory carved out from CMA.
+	 * In normal case, the CMA could be used in kernel; When SVP start, we will
+	 * allocate whole this CMA and pass whole the CMA PA and size into TEE to
+	 * protect it, then the detail memory management also is inside the TEE.
+	 */
+	MTK_SECURE_MEMORY_TYPE_CM_CMA	= 2,
 };
 
 /* This structure also is synchronized with tee, thus not use the phys_addr_t */
@@ -40,7 +49,8 @@  enum mtk_secure_buffer_tee_cmd {
 	 * [in]  value[0].a: The buffer size.
 	 *       value[0].b: alignment.
 	 * [in]  value[1].a: enum mtk_secure_mem_type.
-	 * [inout]
+	 * [inout] [in]  value[2].a: pa base in cma case.
+	 *               value[2].b: The buffer size in cma case.
 	 *         [out] value[2].a: entry number of memory block.
 	 *                           If this is 1, it means the memory is continuous.
 	 *               value[2].b: buffer PA base.
@@ -73,6 +83,9 @@  struct mtk_restricted_heap_data {
 
 	const enum mtk_secure_mem_type mem_type;
 
+	struct page		*cma_page;
+	unsigned long		cma_used_size;
+	struct mutex		lock; /* lock for cma_used_size */
 };
 
 static int mtk_tee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
@@ -173,6 +186,10 @@  static int mtk_tee_restrict_memory(struct restricted_heap *rheap, struct restric
 	params[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT;
 	params[1].u.value.a = data->mem_type;
 	params[2].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT;
+	if (rheap->cma && data->mem_type == MTK_SECURE_MEMORY_TYPE_CM_CMA) {
+		params[2].u.value.a = rheap->cma_paddr;
+		params[2].u.value.b = rheap->cma_size;
+	}
 	params[3].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;
 	ret = mtk_tee_service_call(data->tee_ctx, data->tee_session,
 				   MTK_TZCMD_SECMEM_ZALLOC, params);
@@ -265,6 +282,48 @@  mtk_restricted_memory_free(struct restricted_heap *rheap, struct restricted_buff
 {
 }
 
+static int mtk_restricted_memory_cma_allocate(struct restricted_heap *rheap,
+					      struct restricted_buffer *buf)
+{
+	struct mtk_restricted_heap_data *data = rheap->priv_data;
+	int ret = 0;
+	/*
+	 * Allocate CMA only when allocating buffer for the first time, and just
+	 * increase cma_used_size at the other time, Actually the memory
+	 * allocating is within the TEE.
+	 */
+	mutex_lock(&data->lock);
+	if (!data->cma_used_size) {
+		data->cma_page = cma_alloc(rheap->cma, rheap->cma_size >> PAGE_SHIFT,
+					   get_order(PAGE_SIZE), false);
+		if (!data->cma_page) {
+			ret = -ENOMEM;
+			goto out_unlock;
+		}
+	} else if (data->cma_used_size + buf->size > rheap->cma_size) {
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+	data->cma_used_size += buf->size;
+
+out_unlock:
+	mutex_unlock(&data->lock);
+	return ret;
+}
+
+static void mtk_restricted_memory_cma_free(struct restricted_heap *rheap,
+					   struct restricted_buffer *buf)
+{
+	struct mtk_restricted_heap_data *data = rheap->priv_data;
+
+	mutex_lock(&data->lock);
+	data->cma_used_size -= buf->size;
+	if (!data->cma_used_size)
+		cma_release(rheap->cma, data->cma_page,
+			    rheap->cma_size >> PAGE_SHIFT);
+	mutex_unlock(&data->lock);
+}
+
 static int mtk_restricted_heap_init(struct restricted_heap *rheap)
 {
 	struct mtk_restricted_heap_data *data = rheap->priv_data;
@@ -286,21 +345,77 @@  static struct mtk_restricted_heap_data mtk_restricted_heap_data = {
 	.mem_type		= MTK_SECURE_MEMORY_TYPE_CM_TZ,
 };
 
+static const struct restricted_heap_ops mtk_restricted_heap_ops_cma = {
+	.heap_init		= mtk_restricted_heap_init,
+	.alloc			= mtk_restricted_memory_cma_allocate,
+	.free			= mtk_restricted_memory_cma_free,
+	.restrict_buf		= mtk_tee_restrict_memory,
+	.unrestrict_buf		= mtk_tee_unrestrict_memory,
+};
+
+static struct mtk_restricted_heap_data mtk_restricted_heap_data_cma = {
+	.mem_type		= MTK_SECURE_MEMORY_TYPE_CM_CMA,
+};
+
 static struct restricted_heap mtk_restricted_heaps[] = {
 	{
 		.name		= "restricted_mtk_cm",
 		.ops		= &mtk_restricted_heap_ops,
 		.priv_data	= &mtk_restricted_heap_data,
 	},
+	{
+		.name		= "restricted_mtk_cma",
+		.ops		= &mtk_restricted_heap_ops_cma,
+		.priv_data	= &mtk_restricted_heap_data_cma,
+	},
 };
 
+static int __init mtk_restricted_cma_init(struct reserved_mem *rmem)
+{
+	struct restricted_heap *rheap = mtk_restricted_heaps, *rheap_cma = NULL;
+	struct mtk_restricted_heap_data *data;
+	struct cma *cma;
+	int ret, i;
+
+	for (i = 0; i < ARRAY_SIZE(mtk_restricted_heaps); i++, rheap++) {
+		data = rheap->priv_data;
+		if (data->mem_type == MTK_SECURE_MEMORY_TYPE_CM_CMA) {
+			rheap_cma = rheap;
+			break;
+		}
+	}
+	if (!rheap_cma)
+		return -EINVAL;
+
+	ret = cma_init_reserved_mem(rmem->base, rmem->size, 0, rmem->name,
+				    &cma);
+	if (ret) {
+		pr_err("%s: %s set up CMA fail. ret %d.\n", __func__, rmem->name, ret);
+		return ret;
+	}
+
+	rheap_cma->cma = cma;
+	rheap_cma->cma_paddr = rmem->base;
+	rheap_cma->cma_size = rmem->size;
+	return 0;
+}
+
+RESERVEDMEM_OF_DECLARE(restricted_cma, "mediatek,dynamic-restricted-region",
+		       mtk_restricted_cma_init);
+
 static int mtk_restricted_heap_initialize(void)
 {
 	struct restricted_heap *rheap = mtk_restricted_heaps;
+	struct mtk_restricted_heap_data *data;
 	unsigned int i;
 
-	for (i = 0; i < ARRAY_SIZE(mtk_restricted_heaps); i++, rheap++)
-		restricted_heap_add(rheap);
+	for (i = 0; i < ARRAY_SIZE(mtk_restricted_heaps); i++, rheap++) {
+		data = rheap->priv_data;
+		if (data->mem_type == MTK_SECURE_MEMORY_TYPE_CM_CMA && !rheap->cma)
+			continue;
+		if (!restricted_heap_add(rheap))
+			mutex_init(&data->lock);
+	}
 	return 0;
 }
 module_init(mtk_restricted_heap_initialize);