summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--arch/x86/mm/mem_encrypt.c73
-rw-r--r--lib/dma-direct.c32
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,