Propagate force_dma_unencrypted() into __DMA_ATTR_ALLOC_CC_SHARED in the dma-direct allocation path and use the attribute to drive the related decisions.
This updates dma_direct_alloc(), dma_direct_free(), and dma_direct_alloc_pages() to fold the forced unencrypted case into attrs. Tested-by: Jiri Pirko <[email protected]> Tested-by: Michael Kelley <[email protected]> Tested-by: Mostafa Saleh <[email protected]> Reviewed-by: Petr Tesarik <[email protected]> Signed-off-by: Aneesh Kumar K.V (Arm) <[email protected]> --- kernel/dma/direct.c | 42 +++++++++++++++++++++++++++++++++--------- kernel/dma/mapping.c | 9 +++++++++ 2 files changed, 42 insertions(+), 9 deletions(-) diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 0cbf2b0835c4..98e47e0b332d 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -192,16 +192,22 @@ void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) { bool remap = false, set_uncached = false; - bool mark_mem_decrypt = true; + bool mark_mem_decrypt = false; struct page *page; void *ret; + if (force_dma_unencrypted(dev)) + attrs |= __DMA_ATTR_ALLOC_CC_SHARED; + + if (attrs & __DMA_ATTR_ALLOC_CC_SHARED) + mark_mem_decrypt = true; + size = PAGE_ALIGN(size); if (attrs & DMA_ATTR_NO_WARN) gfp |= __GFP_NOWARN; - if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) && - !force_dma_unencrypted(dev) && !is_swiotlb_for_alloc(dev)) + if (((attrs & (DMA_ATTR_NO_KERNEL_MAPPING | __DMA_ATTR_ALLOC_CC_SHARED)) == + DMA_ATTR_NO_KERNEL_MAPPING) && !is_swiotlb_for_alloc(dev)) return dma_direct_alloc_no_mapping(dev, size, dma_handle, gfp); if (!dev_is_dma_coherent(dev)) { @@ -235,7 +241,7 @@ void *dma_direct_alloc(struct device *dev, size_t size, * Remapping or decrypting memory may block, allocate the memory from * the atomic pools instead if we aren't allowed block. */ - if ((remap || force_dma_unencrypted(dev)) && + if ((remap || (attrs & __DMA_ATTR_ALLOC_CC_SHARED)) && dma_direct_use_pool(dev, gfp)) { page = dma_direct_alloc_from_pool(dev, size, dma_handle, &ret, gfp); @@ -314,12 +320,22 @@ void dma_direct_free(struct device *dev, size_t size, void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs) { phys_addr_t phys; - bool mark_mem_encrypted = true; + bool mark_mem_encrypted = false; struct io_tlb_pool *swiotlb_pool; unsigned int page_order = get_order(size); - if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) && - !force_dma_unencrypted(dev) && !is_swiotlb_for_alloc(dev)) { + /* + * If the allocation used decrypted/shared backing pages, restore + * the encryption state on free. + */ + if (force_dma_unencrypted(dev)) + attrs |= __DMA_ATTR_ALLOC_CC_SHARED; + + if (attrs & __DMA_ATTR_ALLOC_CC_SHARED) + mark_mem_encrypted = true; + + if (((attrs & (DMA_ATTR_NO_KERNEL_MAPPING | __DMA_ATTR_ALLOC_CC_SHARED)) == + DMA_ATTR_NO_KERNEL_MAPPING) && !is_swiotlb_for_alloc(dev)) { /* cpu_addr is a struct page cookie, not a kernel address */ dma_free_contiguous(dev, cpu_addr, size); return; @@ -368,10 +384,14 @@ void dma_direct_free(struct device *dev, size_t size, struct page *dma_direct_alloc_pages(struct device *dev, size_t size, dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp) { + unsigned long attrs = 0; struct page *page; void *ret; - if (force_dma_unencrypted(dev) && dma_direct_use_pool(dev, gfp)) + if (force_dma_unencrypted(dev)) + attrs |= __DMA_ATTR_ALLOC_CC_SHARED; + + if ((attrs & __DMA_ATTR_ALLOC_CC_SHARED) && dma_direct_use_pool(dev, gfp)) return dma_direct_alloc_from_pool(dev, size, dma_handle, &ret, gfp); if (is_swiotlb_for_alloc(dev)) { @@ -405,7 +425,11 @@ void dma_direct_free_pages(struct device *dev, size_t size, phys_addr_t phys; void *vaddr = page_address(page); struct io_tlb_pool *swiotlb_pool; - bool mark_mem_encrypted = true; + /* + * if the device had requested for an unencrypted buffer, + * convert it to encrypted on free + */ + bool mark_mem_encrypted = force_dma_unencrypted(dev); /* If page is not from an atomic pool, dma_free_from_pool_page() fails */ if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) && diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index 4fe04669e5e6..d2f70b6ccd0f 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -638,6 +638,15 @@ void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle, if (WARN_ON_ONCE(flag & __GFP_COMP)) return NULL; + if (attrs & (DMA_ATTR_CC_SHARED | __DMA_ATTR_ALLOC_CC_SHARED)) { + trace_dma_alloc(dev, NULL, 0, size, DMA_BIDIRECTIONAL, flag, + attrs); + return NULL; + } + + if (force_dma_unencrypted(dev)) + attrs |= __DMA_ATTR_ALLOC_CC_SHARED; + if (dma_alloc_from_dev_coherent(dev, size, dma_handle, &cpu_addr)) { trace_dma_alloc(dev, cpu_addr, *dma_handle, size, DMA_BIDIRECTIONAL, flag, attrs); -- 2.43.0
