Initialize a secure heap. Currently just add a null heap, Prepare for the later patches.
Signed-off-by: Yong Wu yong.wu@mediatek.com --- drivers/dma-buf/heaps/Kconfig | 7 +++ drivers/dma-buf/heaps/Makefile | 1 + drivers/dma-buf/heaps/secure_heap.c | 98 +++++++++++++++++++++++++++++ 3 files changed, 106 insertions(+) create mode 100644 drivers/dma-buf/heaps/secure_heap.c
diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma-buf/heaps/Kconfig index a5eef06c4226..e358bf711145 100644 --- a/drivers/dma-buf/heaps/Kconfig +++ b/drivers/dma-buf/heaps/Kconfig @@ -12,3 +12,10 @@ config DMABUF_HEAPS_CMA Choose this option to enable dma-buf CMA heap. This heap is backed by the Contiguous Memory Allocator (CMA). If your system has these regions, you should say Y here. + +config DMABUF_HEAPS_SECURE + bool "DMA-BUF Secure Heap" + depends on DMABUF_HEAPS && TEE + help + Choose this option to enable dma-buf secure heap. This heap is backed by + TEE client interfaces or CMA. If in doubt, say N. diff --git a/drivers/dma-buf/heaps/Makefile b/drivers/dma-buf/heaps/Makefile index 974467791032..b1ad9d1f2fbe 100644 --- a/drivers/dma-buf/heaps/Makefile +++ b/drivers/dma-buf/heaps/Makefile @@ -1,3 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 +obj-$(CONFIG_DMABUF_HEAPS_SECURE) += secure_heap.o obj-$(CONFIG_DMABUF_HEAPS_SYSTEM) += system_heap.o obj-$(CONFIG_DMABUF_HEAPS_CMA) += cma_heap.o diff --git a/drivers/dma-buf/heaps/secure_heap.c b/drivers/dma-buf/heaps/secure_heap.c new file mode 100644 index 000000000000..a634051a0a67 --- /dev/null +++ b/drivers/dma-buf/heaps/secure_heap.c @@ -0,0 +1,98 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DMABUF secure heap exporter + * + * Copyright (C) 2023 MediaTek Inc. + */ + +#include <linux/dma-buf.h> +#include <linux/dma-heap.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/slab.h> + +enum secure_memory_type { + /* + * MediaTek static chunk memory carved out for TrustZone. The memory + * management is inside the TEE. + */ + SECURE_MEMORY_TYPE_MTK_CM_TZ = 1, +}; + +struct secure_buffer { + struct dma_heap *heap; + size_t size; +}; + +struct secure_heap { + const char *name; + const enum secure_memory_type mem_type; +}; + +static struct dma_buf * +secure_heap_allocate(struct dma_heap *heap, unsigned long size, + unsigned long fd_flags, unsigned long heap_flags) +{ + struct secure_buffer *sec_buf; + DEFINE_DMA_BUF_EXPORT_INFO(exp_info); + struct dma_buf *dmabuf; + int ret; + + sec_buf = kzalloc(sizeof(*sec_buf), GFP_KERNEL); + if (!sec_buf) + return ERR_PTR(-ENOMEM); + + sec_buf->size = ALIGN(size, PAGE_SIZE); + sec_buf->heap = heap; + + exp_info.exp_name = dma_heap_get_name(heap); + exp_info.size = sec_buf->size; + exp_info.flags = fd_flags; + exp_info.priv = sec_buf; + + dmabuf = dma_buf_export(&exp_info); + if (IS_ERR(dmabuf)) { + ret = PTR_ERR(dmabuf); + goto err_free_buf; + } + + return dmabuf; + +err_free_buf: + kfree(sec_buf); + return ERR_PTR(ret); +} + +static const struct dma_heap_ops sec_heap_ops = { + .allocate = secure_heap_allocate, +}; + +static struct secure_heap secure_heaps[] = { + { + .name = "secure_mtk_cm", + .mem_type = SECURE_MEMORY_TYPE_MTK_CM_TZ, + }, +}; + +static int secure_heap_init(void) +{ + struct secure_heap *sec_heap = secure_heaps; + struct dma_heap_export_info exp_info; + struct dma_heap *heap; + unsigned int i; + + for (i = 0; i < ARRAY_SIZE(secure_heaps); i++, sec_heap++) { + exp_info.name = sec_heap->name; + exp_info.ops = &sec_heap_ops; + exp_info.priv = (void *)sec_heap; + + heap = dma_heap_add(&exp_info); + if (IS_ERR(heap)) + return PTR_ERR(heap); + } + return 0; +} + +module_init(secure_heap_init); +MODULE_DESCRIPTION("Secure Heap Driver"); +MODULE_LICENSE("GPL");