diff options
| -rw-r--r-- | arch/x86/mm/mem_encrypt.c | 73 | ||||
| -rw-r--r-- | lib/dma-direct.c | 32 |
2 files changed, 29 insertions, 76 deletions
diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c index 1b396422d26f..b2de398d1fd3 100644 --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -195,58 +195,6 @@ void __init sme_early_init(void) swiotlb_force = SWIOTLB_FORCE; } -static void *sev_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, - gfp_t gfp, unsigned long attrs) -{ - unsigned int order; - struct page *page; - void *vaddr = NULL; - - order = get_order(size); - page = alloc_pages_node(dev_to_node(dev), gfp, order); - if (page) { - dma_addr_t addr; - - /* - * Since we will be clearing the encryption bit, check the - * mask with it already cleared. - */ - addr = __phys_to_dma(dev, page_to_phys(page)); - if ((addr + size) > dev->coherent_dma_mask) { - __free_pages(page, get_order(size)); - } else { - vaddr = page_address(page); - *dma_handle = addr; - } - } - - if (!vaddr) - vaddr = swiotlb_alloc_coherent(dev, size, dma_handle, gfp); - - if (!vaddr) - return NULL; - - /* Clear the SME encryption bit for DMA use if not swiotlb area */ - if (!is_swiotlb_buffer(dma_to_phys(dev, *dma_handle))) { - set_memory_decrypted((unsigned long)vaddr, 1 << order); - memset(vaddr, 0, PAGE_SIZE << order); - *dma_handle = __sme_clr(*dma_handle); - } - - return vaddr; -} - -static void sev_free(struct device *dev, size_t size, void *vaddr, - dma_addr_t dma_handle, unsigned long attrs) -{ - /* Set the SME encryption bit for re-use if not swiotlb area */ - if (!is_swiotlb_buffer(dma_to_phys(dev, dma_handle))) - set_memory_encrypted((unsigned long)vaddr, - 1 << get_order(size)); - - swiotlb_free_coherent(dev, size, vaddr, dma_handle); -} - static void __init __set_clr_pte_enc(pte_t *kpte, int level, bool enc) { pgprot_t old_prot, new_prot; @@ -399,20 +347,6 @@ bool sev_active(void) } EXPORT_SYMBOL(sev_active); -static const struct dma_map_ops sev_dma_ops = { - .alloc = sev_alloc, - .free = sev_free, - .map_page = swiotlb_map_page, - .unmap_page = swiotlb_unmap_page, - .map_sg = swiotlb_map_sg_attrs, - .unmap_sg = swiotlb_unmap_sg_attrs, - .sync_single_for_cpu = swiotlb_sync_single_for_cpu, - .sync_single_for_device = swiotlb_sync_single_for_device, - .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu, - .sync_sg_for_device = swiotlb_sync_sg_for_device, - .mapping_error = swiotlb_dma_mapping_error, -}; - /* Architecture __weak replacement functions */ void __init mem_encrypt_init(void) { @@ -423,12 +357,11 @@ void __init mem_encrypt_init(void) swiotlb_update_mem_attributes(); /* - * With SEV, DMA operations cannot use encryption. New DMA ops - * are required in order to mark the DMA areas as decrypted or - * to use bounce buffers. + * With SEV, DMA operations cannot use encryption, we need to use + * SWIOTLB to bounce buffer DMA operation. */ if (sev_active()) - dma_ops = &sev_dma_ops; + dma_ops = &swiotlb_dma_ops; /* * With SEV, we need to unroll the rep string I/O instructions. diff --git a/lib/dma-direct.c b/lib/dma-direct.c index c9e8e21cb334..1277d293d4da 100644 --- a/lib/dma-direct.c +++ b/lib/dma-direct.c @@ -9,6 +9,7 @@ #include <linux/scatterlist.h> #include <linux/dma-contiguous.h> #include <linux/pfn.h> +#include <linux/set_memory.h> #define DIRECT_MAPPING_ERROR 0 @@ -20,6 +21,14 @@ #define ARCH_ZONE_DMA_BITS 24 #endif +/* + * For AMD SEV all DMA must be to unencrypted addresses. + */ +static inline bool force_dma_unencrypted(void) +{ + return sev_active(); +} + static bool check_addr(struct device *dev, dma_addr_t dma_addr, size_t size, const char *caller) @@ -37,7 +46,9 @@ check_addr(struct device *dev, dma_addr_t dma_addr, size_t size, static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size) { - return phys_to_dma(dev, phys) + size - 1 <= dev->coherent_dma_mask; + dma_addr_t addr = force_dma_unencrypted() ? + __phys_to_dma(dev, phys) : phys_to_dma(dev, phys); + return addr + size - 1 <= dev->coherent_dma_mask; } void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, @@ -46,6 +57,7 @@ void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT; int page_order = get_order(size); struct page *page = NULL; + void *ret; /* GFP_DMA32 and GFP_DMA are no ops without the corresponding zones: */ if (dev->coherent_dma_mask <= DMA_BIT_MASK(ARCH_ZONE_DMA_BITS)) @@ -78,10 +90,15 @@ again: if (!page) return NULL; - - *dma_handle = phys_to_dma(dev, page_to_phys(page)); - memset(page_address(page), 0, size); - return page_address(page); + ret = page_address(page); + if (force_dma_unencrypted()) { + set_memory_decrypted((unsigned long)ret, 1 << page_order); + *dma_handle = __phys_to_dma(dev, page_to_phys(page)); + } else { + *dma_handle = phys_to_dma(dev, page_to_phys(page)); + } + memset(ret, 0, size); + return ret; } /* @@ -92,9 +109,12 @@ void dma_direct_free(struct device *dev, size_t size, void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs) { unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT; + unsigned int page_order = get_order(size); + if (force_dma_unencrypted()) + set_memory_encrypted((unsigned long)cpu_addr, 1 << page_order); if (!dma_release_from_contiguous(dev, virt_to_page(cpu_addr), count)) - free_pages((unsigned long)cpu_addr, get_order(size)); + free_pages((unsigned long)cpu_addr, page_order); } static dma_addr_t dma_direct_map_page(struct device *dev, struct page *page, |