Merge tag 'dma-mapping-5.3-1' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping fixes from Christoph Hellwig:
 "Fix various regressions:

   - force unencrypted dma-coherent buffers if encryption bit can't fit
     into the dma coherent mask (Tom Lendacky)

   - avoid limiting request size if swiotlb is not used (me)

   - fix swiotlb handling in dma_direct_sync_sg_for_cpu/device (Fugang
     Duan)"

* tag 'dma-mapping-5.3-1' of git://git.infradead.org/users/hch/dma-mapping:
  dma-direct: correct the physical addr in dma_direct_sync_sg_for_cpu/device
  dma-direct: only limit the mapping size if swiotlb could be used
  dma-mapping: add a dma_addressing_limited helper
  dma-direct: Force unencrypted DMA under SME for certain DMA masks

2 files changed, 22 insertions, 25 deletions

diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
index 70f8f8d9200e..9decbba255fc 100644
--- a/kernel/dma/Kconfig
+++ b/kernel/dma/Kconfig
@@ -48,6 +48,9 @@ config ARCH_HAS_DMA_COHERENT_TO_PFN
 config ARCH_HAS_DMA_MMAP_PGPROT
 	bool
 
+config ARCH_HAS_FORCE_DMA_UNENCRYPTED
+	bool
+
 config DMA_NONCOHERENT_CACHE_SYNC
 	bool
 
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index b90e1aede743..59bdceea3737 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -23,14 +23,6 @@
 #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 void report_addr(struct device *dev, dma_addr_t dma_addr, size_t size)
 {
 	if (!dev->dma_mask) {
@@ -46,7 +38,7 @@ static void report_addr(struct device *dev, dma_addr_t dma_addr, size_t size)
 static inline dma_addr_t phys_to_dma_direct(struct device *dev,
 		phys_addr_t phys)
 {
-	if (force_dma_unencrypted())
+	if (force_dma_unencrypted(dev))
 		return __phys_to_dma(dev, phys);
 	return phys_to_dma(dev, phys);
 }
@@ -67,7 +59,7 @@ static gfp_t __dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask,
 	if (dev->bus_dma_mask && dev->bus_dma_mask < dma_mask)
 		dma_mask = dev->bus_dma_mask;
 
-	if (force_dma_unencrypted())
+	if (force_dma_unencrypted(dev))
 		*phys_mask = __dma_to_phys(dev, dma_mask);
 	else
 		*phys_mask = dma_to_phys(dev, dma_mask);
@@ -159,7 +151,7 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size,
 	}
 
 	ret = page_address(page);
-	if (force_dma_unencrypted()) {
+	if (force_dma_unencrypted(dev)) {
 		set_memory_decrypted((unsigned long)ret, 1 << get_order(size));
 		*dma_handle = __phys_to_dma(dev, page_to_phys(page));
 	} else {
@@ -192,7 +184,7 @@ void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr,
 		return;
 	}
 
-	if (force_dma_unencrypted())
+	if (force_dma_unencrypted(dev))
 		set_memory_encrypted((unsigned long)cpu_addr, 1 << page_order);
 
 	if (IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) &&
@@ -242,12 +234,14 @@ void dma_direct_sync_sg_for_device(struct device *dev,
 	int i;
 
 	for_each_sg(sgl, sg, nents, i) {
-		if (unlikely(is_swiotlb_buffer(sg_phys(sg))))
-			swiotlb_tbl_sync_single(dev, sg_phys(sg), sg->length,
+		phys_addr_t paddr = dma_to_phys(dev, sg_dma_address(sg));
+
+		if (unlikely(is_swiotlb_buffer(paddr)))
+			swiotlb_tbl_sync_single(dev, paddr, sg->length,
 					dir, SYNC_FOR_DEVICE);
 
 		if (!dev_is_dma_coherent(dev))
-			arch_sync_dma_for_device(dev, sg_phys(sg), sg->length,
+			arch_sync_dma_for_device(dev, paddr, sg->length,
 					dir);
 	}
 }
@@ -279,11 +273,13 @@ void dma_direct_sync_sg_for_cpu(struct device *dev,
 	int i;
 
 	for_each_sg(sgl, sg, nents, i) {
+		phys_addr_t paddr = dma_to_phys(dev, sg_dma_address(sg));
+
 		if (!dev_is_dma_coherent(dev))
-			arch_sync_dma_for_cpu(dev, sg_phys(sg), sg->length, dir);
-	
-		if (unlikely(is_swiotlb_buffer(sg_phys(sg))))
-			swiotlb_tbl_sync_single(dev, sg_phys(sg), sg->length, dir,
+			arch_sync_dma_for_cpu(dev, paddr, sg->length, dir);
+
+		if (unlikely(is_swiotlb_buffer(paddr)))
+			swiotlb_tbl_sync_single(dev, paddr, sg->length, dir,
 					SYNC_FOR_CPU);
 	}
 
@@ -407,11 +403,9 @@ int dma_direct_supported(struct device *dev, u64 mask)
 
 size_t dma_direct_max_mapping_size(struct device *dev)
 {
-	size_t size = SIZE_MAX;
-
 	/* If SWIOTLB is active, use its maximum mapping size */
-	if (is_swiotlb_active())
-		size = swiotlb_max_mapping_size(dev);
-
-	return size;
+	if (is_swiotlb_active() &&
+	    (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE))
+		return swiotlb_max_mapping_size(dev);
+	return SIZE_MAX;
 }