Merge branch 'x86-dma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 dma mapping updates from Ingo Molnar:
 "This tree, by Christoph Hellwig, switches over the x86 architecture to
  the generic dma-direct and swiotlb code, and also unifies more of the
  dma-direct code between architectures. The now unused x86-only
  primitives are removed"

* 'x86-dma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  dma-mapping: Don't clear GFP_ZERO in dma_alloc_attrs
  swiotlb: Make swiotlb_{alloc,free}_buffer depend on CONFIG_DMA_DIRECT_OPS
  dma/swiotlb: Remove swiotlb_{alloc,free}_coherent()
  dma/direct: Handle force decryption for DMA coherent buffers in common code
  dma/direct: Handle the memory encryption bit in common code
  dma/swiotlb: Remove swiotlb_set_mem_attributes()
  set_memory.h: Provide set_memory_{en,de}crypted() stubs
  x86/dma: Remove dma_alloc_coherent_gfp_flags()
  iommu/intel-iommu: Enable CONFIG_DMA_DIRECT_OPS=y and clean up intel_{alloc,free}_coherent()
  iommu/amd_iommu: Use CONFIG_DMA_DIRECT_OPS=y and dma_direct_{alloc,free}()
  x86/dma/amd_gart: Use dma_direct_{alloc,free}()
  x86/dma/amd_gart: Look at dev->coherent_dma_mask instead of GFP_DMA
  x86/dma: Use generic swiotlb_ops
  x86/dma: Use DMA-direct (CONFIG_DMA_DIRECT_OPS=y)
  x86/dma: Remove dma_alloc_coherent_mask()

arch/arm/include/asm/dma-direct.h

@@ -2,13 +2,13 @@
 #ifndef ASM_ARM_DMA_DIRECT_H
 #define ASM_ARM_DMA_DIRECT_H 1
 
-static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
+static inline dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr)
 {
 	unsigned int offset = paddr & ~PAGE_MASK;
 	return pfn_to_dma(dev, __phys_to_pfn(paddr)) + offset;
 }
 
-static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
+static inline phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t dev_addr)
 {
 	unsigned int offset = dev_addr & ~PAGE_MASK;
 	return __pfn_to_phys(dma_to_pfn(dev, dev_addr)) + offset;

arch/mips/cavium-octeon/dma-octeon.c

@@ -10,7 +10,7 @@
  * IP32 changes by Ilya.
  * Copyright (C) 2010 Cavium Networks, Inc.
  */
-#include <linux/dma-mapping.h>
+#include <linux/dma-direct.h>
 #include <linux/scatterlist.h>
 #include <linux/bootmem.h>
 #include <linux/export.h>
@@ -182,7 +182,7 @@ struct octeon_dma_map_ops {
 	phys_addr_t (*dma_to_phys)(struct device *dev, dma_addr_t daddr);
 };
 
-dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
+dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr)
 {
 	struct octeon_dma_map_ops *ops = container_of(get_dma_ops(dev),
 						      struct octeon_dma_map_ops,
@@ -190,9 +190,9 @@ dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
 
 	return ops->phys_to_dma(dev, paddr);
 }
-EXPORT_SYMBOL(phys_to_dma);
+EXPORT_SYMBOL(__phys_to_dma);
 
-phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
+phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t daddr)
 {
 	struct octeon_dma_map_ops *ops = container_of(get_dma_ops(dev),
 						      struct octeon_dma_map_ops,
@@ -200,7 +200,7 @@ phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
 
 	return ops->dma_to_phys(dev, daddr);
 }
-EXPORT_SYMBOL(dma_to_phys);
+EXPORT_SYMBOL(__dma_to_phys);
 
 static struct octeon_dma_map_ops octeon_linear_dma_map_ops = {
 	.dma_map_ops = {

arch/mips/include/asm/mach-cavium-octeon/dma-coherence.h

@@ -69,8 +69,8 @@ static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
 	return addr + size - 1 <= *dev->dma_mask;
 }
 
-dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr);
-phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr);
+dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr);
+phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t daddr);
 
 struct dma_map_ops;
 extern const struct dma_map_ops *octeon_pci_dma_map_ops;

arch/mips/include/asm/mach-loongson64/dma-coherence.h

@@ -25,13 +25,13 @@ static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
 	return addr + size - 1 <= *dev->dma_mask;
 }
 
-extern dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr);
-extern phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr);
+extern dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr);
+extern phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t daddr);
 static inline dma_addr_t plat_map_dma_mem(struct device *dev, void *addr,
 					  size_t size)
 {
 #ifdef CONFIG_CPU_LOONGSON3
-	return phys_to_dma(dev, virt_to_phys(addr));
+	return __phys_to_dma(dev, virt_to_phys(addr));
 #else
 	return virt_to_phys(addr) | 0x80000000;
 #endif
@@ -41,7 +41,7 @@ static inline dma_addr_t plat_map_dma_mem_page(struct device *dev,
 					       struct page *page)
 {
 #ifdef CONFIG_CPU_LOONGSON3
-	return phys_to_dma(dev, page_to_phys(page));
+	return __phys_to_dma(dev, page_to_phys(page));
 #else
 	return page_to_phys(page) | 0x80000000;
 #endif
@@ -51,7 +51,7 @@ static inline unsigned long plat_dma_addr_to_phys(struct device *dev,
 	dma_addr_t dma_addr)
 {
 #if defined(CONFIG_CPU_LOONGSON3) && defined(CONFIG_64BIT)
-	return dma_to_phys(dev, dma_addr);
+	return __dma_to_phys(dev, dma_addr);
 #elif defined(CONFIG_CPU_LOONGSON2F) && defined(CONFIG_64BIT)
 	return (dma_addr > 0x8fffffff) ? dma_addr : (dma_addr & 0x0fffffff);
 #else

arch/mips/loongson64/common/dma-swiotlb.c

@@ -63,7 +63,7 @@ static int loongson_dma_supported(struct device *dev, u64 mask)
 	return swiotlb_dma_supported(dev, mask);
 }
 
-dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
+dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr)
 {
 	long nid;
 #ifdef CONFIG_PHYS48_TO_HT40
@@ -75,7 +75,7 @@ dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
 	return paddr;
 }
 
-phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
+phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t daddr)
 {
 	long nid;
 #ifdef CONFIG_PHYS48_TO_HT40

arch/powerpc/include/asm/dma-direct.h

@@ -17,12 +17,12 @@ static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
 	return addr + size - 1 <= *dev->dma_mask;
 }
 
-static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
+static inline dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr)
 {
 	return paddr + get_dma_offset(dev);
 }
 
-static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
+static inline phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t daddr)
 {
 	return daddr - get_dma_offset(dev);
 }

arch/x86/Kconfig

@@ -54,7 +54,6 @@ config X86
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_GCOV_PROFILE_ALL
 	select ARCH_HAS_KCOV			if X86_64
-	select ARCH_HAS_PHYS_TO_DMA
 	select ARCH_HAS_MEMBARRIER_SYNC_CORE
 	select ARCH_HAS_PMEM_API		if X86_64
 	select ARCH_HAS_REFCOUNT
@@ -83,6 +82,7 @@ config X86
 	select CLOCKSOURCE_VALIDATE_LAST_CYCLE
 	select CLOCKSOURCE_WATCHDOG
 	select DCACHE_WORD_ACCESS
+	select DMA_DIRECT_OPS
 	select EDAC_ATOMIC_SCRUB
 	select EDAC_SUPPORT
 	select GENERIC_CLOCKEVENTS
@@ -680,6 +680,7 @@ config X86_SUPPORTS_MEMORY_FAILURE
 config STA2X11
 	bool "STA2X11 Companion Chip Support"
 	depends on X86_32_NON_STANDARD && PCI
+	select ARCH_HAS_PHYS_TO_DMA
 	select X86_DEV_DMA_OPS
 	select X86_DMA_REMAP
 	select SWIOTLB

arch/x86/include/asm/device.h

@@ -6,6 +6,9 @@ struct dev_archdata {
 #if defined(CONFIG_INTEL_IOMMU) || defined(CONFIG_AMD_IOMMU)
 	void *iommu; /* hook for IOMMU specific extension */
 #endif
+#ifdef CONFIG_STA2X11
+	bool is_sta2x11;
+#endif
 };
 
 #if defined(CONFIG_X86_DEV_DMA_OPS) && defined(CONFIG_PCI_DOMAINS)

arch/x86/include/asm/dma-direct.h

@@ -2,29 +2,8 @@
 #ifndef ASM_X86_DMA_DIRECT_H
 #define ASM_X86_DMA_DIRECT_H 1
 
-#include <linux/mem_encrypt.h>
-
-#ifdef CONFIG_X86_DMA_REMAP /* Platform code defines bridge-specific code */
 bool dma_capable(struct device *dev, dma_addr_t addr, size_t size);
-dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr);
-phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr);
-#else
-static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
-{
-	if (!dev->dma_mask)
-		return 0;
-
-	return addr + size - 1 <= *dev->dma_mask;
-}
-
-static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
-{
-	return __sme_set(paddr);
-}
+dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr);
+phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t daddr);
 
-static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
-{
-	return __sme_clr(daddr);
-}
-#endif /* CONFIG_X86_DMA_REMAP */
 #endif /* ASM_X86_DMA_DIRECT_H */

arch/x86/include/asm/dma-mapping.h

@@ -36,37 +36,4 @@ int arch_dma_supported(struct device *dev, u64 mask);
 bool arch_dma_alloc_attrs(struct device **dev, gfp_t *gfp);
 #define arch_dma_alloc_attrs arch_dma_alloc_attrs
 
-extern void *dma_generic_alloc_coherent(struct device *dev, size_t size,
-					dma_addr_t *dma_addr, gfp_t flag,
-					unsigned long attrs);
-
-extern void dma_generic_free_coherent(struct device *dev, size_t size,
-				      void *vaddr, dma_addr_t dma_addr,
-				      unsigned long attrs);
-
-static inline unsigned long dma_alloc_coherent_mask(struct device *dev,
-						    gfp_t gfp)
-{
-	unsigned long dma_mask = 0;
-
-	dma_mask = dev->coherent_dma_mask;
-	if (!dma_mask)
-		dma_mask = (gfp & GFP_DMA) ? DMA_BIT_MASK(24) : DMA_BIT_MASK(32);
-
-	return dma_mask;
-}
-
-static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp)
-{
-	unsigned long dma_mask = dma_alloc_coherent_mask(dev, gfp);
-
-	if (dma_mask <= DMA_BIT_MASK(24))
-		gfp |= GFP_DMA;
-#ifdef CONFIG_X86_64
-	if (dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA))
-		gfp |= GFP_DMA32;
-#endif
-       return gfp;
-}
-
 #endif

arch/x86/include/asm/iommu.h

@@ -2,13 +2,10 @@
 #ifndef _ASM_X86_IOMMU_H
 #define _ASM_X86_IOMMU_H
 
-extern const struct dma_map_ops nommu_dma_ops;
 extern int force_iommu, no_iommu;
 extern int iommu_detected;
 extern int iommu_pass_through;
 
-int x86_dma_supported(struct device *dev, u64 mask);
-
 /* 10 seconds */
 #define DMAR_OPERATION_TIMEOUT ((cycles_t) tsc_khz*10*1000)
 

arch/x86/include/asm/mem_encrypt.h

@@ -49,8 +49,6 @@ int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size);
 /* Architecture __weak replacement functions */
 void __init mem_encrypt_init(void);
 
-void swiotlb_set_mem_attributes(void *vaddr, unsigned long size);
-
 bool sme_active(void);
 bool sev_active(void);
 

arch/x86/include/asm/swiotlb.h

@@ -27,12 +27,4 @@ static inline void pci_swiotlb_late_init(void)
 {
 }
 #endif
-
-extern void *x86_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
-					dma_addr_t *dma_handle, gfp_t flags,
-					unsigned long attrs);
-extern void x86_swiotlb_free_coherent(struct device *dev, size_t size,
-					void *vaddr, dma_addr_t dma_addr,
-					unsigned long attrs);
-
 #endif /* _ASM_X86_SWIOTLB_H */

arch/x86/kernel/Makefile

@@ -57,7 +57,7 @@ obj-$(CONFIG_X86_ESPFIX64)	+= espfix_64.o
 obj-$(CONFIG_SYSFS)	+= ksysfs.o
 obj-y			+= bootflag.o e820.o
 obj-y			+= pci-dma.o quirks.o topology.o kdebugfs.o
-obj-y			+= alternative.o i8253.o pci-nommu.o hw_breakpoint.o
+obj-y			+= alternative.o i8253.o hw_breakpoint.o
 obj-y			+= tsc.o tsc_msr.o io_delay.o rtc.o
 obj-y			+= pci-iommu_table.o
 obj-y			+= resource.o

arch/x86/kernel/amd_gart_64.c

@@ -480,30 +480,21 @@ static void *
 gart_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_addr,
 		    gfp_t flag, unsigned long attrs)
 {
-	dma_addr_t paddr;
-	unsigned long align_mask;
-	struct page *page;
-
-	if (force_iommu && !(flag & GFP_DMA)) {
-		flag &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
-		page = alloc_pages(flag | __GFP_ZERO, get_order(size));
-		if (!page)
-			return NULL;
-
-		align_mask = (1UL << get_order(size)) - 1;
-		paddr = dma_map_area(dev, page_to_phys(page), size,
-				     DMA_BIDIRECTIONAL, align_mask);
-
-		flush_gart();
-		if (paddr != bad_dma_addr) {
-			*dma_addr = paddr;
-			return page_address(page);
-		}
-		__free_pages(page, get_order(size));
-	} else
-		return dma_generic_alloc_coherent(dev, size, dma_addr, flag,
-						  attrs);
+	void *vaddr;
+
+	vaddr = dma_direct_alloc(dev, size, dma_addr, flag, attrs);
+	if (!vaddr ||
+	    !force_iommu || dev->coherent_dma_mask <= DMA_BIT_MASK(24))
+		return vaddr;
 
+	*dma_addr = dma_map_area(dev, virt_to_phys(vaddr), size,
+			DMA_BIDIRECTIONAL, (1UL << get_order(size)) - 1);
+	flush_gart();
+	if (unlikely(*dma_addr == bad_dma_addr))
+		goto out_free;
+	return vaddr;
+out_free:
+	dma_direct_free(dev, size, vaddr, *dma_addr, attrs);
 	return NULL;
 }
 
@@ -513,7 +504,7 @@ gart_free_coherent(struct device *dev, size_t size, void *vaddr,
 		   dma_addr_t dma_addr, unsigned long attrs)
 {
 	gart_unmap_page(dev, dma_addr, size, DMA_BIDIRECTIONAL, 0);
-	dma_generic_free_coherent(dev, size, vaddr, dma_addr, attrs);
+	dma_direct_free(dev, size, vaddr, dma_addr, attrs);
 }
 
 static int gart_mapping_error(struct device *dev, dma_addr_t dma_addr)
@@ -705,7 +696,7 @@ static const struct dma_map_ops gart_dma_ops = {
 	.alloc				= gart_alloc_coherent,
 	.free				= gart_free_coherent,
 	.mapping_error			= gart_mapping_error,
-	.dma_supported			= x86_dma_supported,
+	.dma_supported			= dma_direct_supported,
 };
 
 static void gart_iommu_shutdown(void)

arch/x86/kernel/pci-calgary_64.c

@@ -33,6 +33,7 @@
 #include <linux/string.h>
 #include <linux/crash_dump.h>
 #include <linux/dma-mapping.h>
+#include <linux/dma-direct.h>
 #include <linux/bitmap.h>
 #include <linux/pci_ids.h>
 #include <linux/pci.h>
@@ -445,8 +446,6 @@ static void* calgary_alloc_coherent(struct device *dev, size_t size,
 	npages = size >> PAGE_SHIFT;
 	order = get_order(size);
 
-	flag &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
-
 	/* alloc enough pages (and possibly more) */
 	ret = (void *)__get_free_pages(flag, order);
 	if (!ret)
@@ -493,7 +492,7 @@ static const struct dma_map_ops calgary_dma_ops = {
 	.map_page = calgary_map_page,
 	.unmap_page = calgary_unmap_page,
 	.mapping_error = calgary_mapping_error,
-	.dma_supported = x86_dma_supported,
+	.dma_supported = dma_direct_supported,
 };
 
 static inline void __iomem * busno_to_bbar(unsigned char num)

arch/x86/kernel/pci-dma.c

@@ -18,7 +18,7 @@
 
 static int forbid_dac __read_mostly;
 
-const struct dma_map_ops *dma_ops = &nommu_dma_ops;
+const struct dma_map_ops *dma_ops = &dma_direct_ops;
 EXPORT_SYMBOL(dma_ops);
 
 static int iommu_sac_force __read_mostly;
@@ -76,70 +76,12 @@ void __init pci_iommu_alloc(void)
 		}
 	}
 }
-void *dma_generic_alloc_coherent(struct device *dev, size_t size,
-				 dma_addr_t *dma_addr, gfp_t flag,
-				 unsigned long attrs)
-{
-	unsigned long dma_mask;
-	struct page *page;
-	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
-	dma_addr_t addr;
-
-	dma_mask = dma_alloc_coherent_mask(dev, flag);
-
-again:
-	page = NULL;
-	/* CMA can be used only in the context which permits sleeping */
-	if (gfpflags_allow_blocking(flag)) {
-		page = dma_alloc_from_contiguous(dev, count, get_order(size),
-						 flag);
-		if (page) {
-			addr = phys_to_dma(dev, page_to_phys(page));
-			if (addr + size > dma_mask) {
-				dma_release_from_contiguous(dev, page, count);
-				page = NULL;
-			}
-		}
-	}
-	/* fallback */
-	if (!page)
-		page = alloc_pages_node(dev_to_node(dev), flag, get_order(size));
-	if (!page)
-		return NULL;
-
-	addr = phys_to_dma(dev, page_to_phys(page));
-	if (addr + size > dma_mask) {
-		__free_pages(page, get_order(size));
-
-		if (dma_mask < DMA_BIT_MASK(32) && !(flag & GFP_DMA)) {
-			flag = (flag & ~GFP_DMA32) | GFP_DMA;
-			goto again;
-		}
-
-		return NULL;
-	}
-	memset(page_address(page), 0, size);
-	*dma_addr = addr;
-	return page_address(page);
-}
-
-void dma_generic_free_coherent(struct device *dev, size_t size, void *vaddr,
-			       dma_addr_t dma_addr, unsigned long attrs)
-{
-	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
-	struct page *page = virt_to_page(vaddr);
-
-	if (!dma_release_from_contiguous(dev, page, count))
-		free_pages((unsigned long)vaddr, get_order(size));
-}
 
 bool arch_dma_alloc_attrs(struct device **dev, gfp_t *gfp)
 {
 	if (!*dev)
 		*dev = &x86_dma_fallback_dev;
 
-	*gfp = dma_alloc_coherent_gfp_flags(*dev, *gfp);
-
 	if (!is_device_dma_capable(*dev))
 		return false;
 	return true;
@@ -245,16 +187,6 @@ int arch_dma_supported(struct device *dev, u64 mask)
 }
 EXPORT_SYMBOL(arch_dma_supported);
 
-int x86_dma_supported(struct device *dev, u64 mask)
-{
-	/* Copied from i386. Doesn't make much sense, because it will
-	   only work for pci_alloc_coherent.
-	   The caller just has to use GFP_DMA in this case. */
-	if (mask < DMA_BIT_MASK(24))
-		return 0;
-	return 1;
-}
-
 static int __init pci_iommu_init(void)
 {
 	struct iommu_table_entry *p;

arch/x86/kernel/pci-swiotlb.c

@@ -17,52 +17,6 @@
 
 int swiotlb __read_mostly;
 
-void *x86_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
-					dma_addr_t *dma_handle, gfp_t flags,
-					unsigned long attrs)
-{
-	void *vaddr;
-
-	/*
-	 * Don't print a warning when the first allocation attempt fails.
-	 * swiotlb_alloc_coherent() will print a warning when the DMA
-	 * memory allocation ultimately failed.
-	 */
-	flags |= __GFP_NOWARN;
-
-	vaddr = dma_generic_alloc_coherent(hwdev, size, dma_handle, flags,
-					   attrs);
-	if (vaddr)
-		return vaddr;
-
-	return swiotlb_alloc_coherent(hwdev, size, dma_handle, flags);
-}
-
-void x86_swiotlb_free_coherent(struct device *dev, size_t size,
-				      void *vaddr, dma_addr_t dma_addr,
-				      unsigned long attrs)
-{
-	if (is_swiotlb_buffer(dma_to_phys(dev, dma_addr)))
-		swiotlb_free_coherent(dev, size, vaddr, dma_addr);
-	else
-		dma_generic_free_coherent(dev, size, vaddr, dma_addr, attrs);
-}
-
-static const struct dma_map_ops x86_swiotlb_dma_ops = {
-	.mapping_error = swiotlb_dma_mapping_error,
-	.alloc = x86_swiotlb_alloc_coherent,
-	.free = x86_swiotlb_free_coherent,
-	.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,
-	.map_sg = swiotlb_map_sg_attrs,
-	.unmap_sg = swiotlb_unmap_sg_attrs,
-	.map_page = swiotlb_map_page,
-	.unmap_page = swiotlb_unmap_page,
-	.dma_supported = NULL,
-};
-
 /*
  * pci_swiotlb_detect_override - set swiotlb to 1 if necessary
  *
@@ -112,7 +66,7 @@ void __init pci_swiotlb_init(void)
 {
 	if (swiotlb) {
 		swiotlb_init(0);
-		dma_ops = &x86_swiotlb_dma_ops;
+		dma_ops = &swiotlb_dma_ops;
 	}
 }
 

arch/x86/mm/mem_encrypt.c

@@ -195,67 +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 long dma_mask;
-	unsigned int order;
-	struct page *page;
-	void *vaddr = NULL;
-
-	dma_mask = dma_alloc_coherent_mask(dev, gfp);
-	order = get_order(size);
-
-	/*
-	 * Memory will be memset to zero after marking decrypted, so don't
-	 * bother clearing it before.
-	 */
-	gfp &= ~__GFP_ZERO;
-
-	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 = __sme_clr(phys_to_dma(dev, page_to_phys(page)));
-		if ((addr + size) > 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;
@@ -408,20 +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)
 {
@@ -432,12 +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.
@@ -450,11 +374,3 @@ void __init mem_encrypt_init(void)
 			     : "Secure Memory Encryption (SME)");
 }
 
-void swiotlb_set_mem_attributes(void *vaddr, unsigned long size)
-{
-	WARN(PAGE_ALIGN(size) != size,
-	     "size is not page-aligned (%#lx)\n", size);
-
-	/* Make the SWIOTLB buffer area decrypted */
-	set_memory_decrypted((unsigned long)vaddr, size >> PAGE_SHIFT);
-}

arch/x86/pci/sta2x11-fixup.c

@@ -159,43 +159,6 @@ static dma_addr_t a2p(dma_addr_t a, struct pci_dev *pdev)
 	return p;
 }
 
-/**
- * sta2x11_swiotlb_alloc_coherent - Allocate swiotlb bounce buffers
- *     returns virtual address. This is the only "special" function here.
- * @dev: PCI device
- * @size: Size of the buffer
- * @dma_handle: DMA address
- * @flags: memory flags
- */
-static void *sta2x11_swiotlb_alloc_coherent(struct device *dev,
-					    size_t size,
-					    dma_addr_t *dma_handle,
-					    gfp_t flags,
-					    unsigned long attrs)
-{
-	void *vaddr;
-
-	vaddr = x86_swiotlb_alloc_coherent(dev, size, dma_handle, flags, attrs);
-	*dma_handle = p2a(*dma_handle, to_pci_dev(dev));
-	return vaddr;
-}
-
-/* We have our own dma_ops: the same as swiotlb but from alloc (above) */
-static const struct dma_map_ops sta2x11_dma_ops = {
-	.alloc = sta2x11_swiotlb_alloc_coherent,
-	.free = x86_swiotlb_free_coherent,
-	.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,
-	.dma_supported = x86_dma_supported,
-};
-
 /* At setup time, we use our own ops if the device is a ConneXt one */
 static void sta2x11_setup_pdev(struct pci_dev *pdev)
 {
@@ -205,7 +168,8 @@ static void sta2x11_setup_pdev(struct pci_dev *pdev)
 		return;
 	pci_set_consistent_dma_mask(pdev, STA2X11_AMBA_SIZE - 1);
 	pci_set_dma_mask(pdev, STA2X11_AMBA_SIZE - 1);
-	pdev->dev.dma_ops = &sta2x11_dma_ops;
+	pdev->dev.dma_ops = &swiotlb_dma_ops;
+	pdev->dev.archdata.is_sta2x11 = true;
 
 	/* We must enable all devices as master, for audio DMA to work */
 	pci_set_master(pdev);
@@ -225,7 +189,7 @@ bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
 {
 	struct sta2x11_mapping *map;
 
-	if (dev->dma_ops != &sta2x11_dma_ops) {
+	if (!dev->archdata.is_sta2x11) {
 		if (!dev->dma_mask)
 			return false;
 		return addr + size - 1 <= *dev->dma_mask;
@@ -243,13 +207,13 @@ bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
 }
 
 /**
- * phys_to_dma - Return the DMA AMBA address used for this STA2x11 device
+ * __phys_to_dma - Return the DMA AMBA address used for this STA2x11 device
  * @dev: device for a PCI device
  * @paddr: Physical address
  */
-dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
+dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr)
 {
-	if (dev->dma_ops != &sta2x11_dma_ops)
+	if (!dev->archdata.is_sta2x11)
 		return paddr;
 	return p2a(paddr, to_pci_dev(dev));
 }
@@ -259,9 +223,9 @@ dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
  * @dev: device for a PCI device
  * @daddr: STA2x11 AMBA DMA address
  */
-phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
+phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t daddr)
 {
-	if (dev->dma_ops != &sta2x11_dma_ops)
+	if (!dev->archdata.is_sta2x11)
 		return daddr;
 	return a2p(daddr, to_pci_dev(dev));
 }

drivers/iommu/Kconfig

@@ -107,6 +107,7 @@ config IOMMU_PGTABLES_L2
 # AMD IOMMU support
 config AMD_IOMMU
 	bool "AMD IOMMU support"
+	select DMA_DIRECT_OPS
 	select SWIOTLB
 	select PCI_MSI
 	select PCI_ATS
@@ -142,6 +143,7 @@ config DMAR_TABLE
 config INTEL_IOMMU
 	bool "Support for Intel IOMMU using DMA Remapping Devices"
 	depends on PCI_MSI && ACPI && (X86 || IA64_GENERIC)
+	select DMA_DIRECT_OPS
 	select IOMMU_API
 	select IOMMU_IOVA
 	select DMAR_TABLE

drivers/iommu/amd_iommu.c

@@ -28,6 +28,7 @@
 #include <linux/debugfs.h>
 #include <linux/scatterlist.h>
 #include <linux/dma-mapping.h>
+#include <linux/dma-direct.h>
 #include <linux/iommu-helper.h>
 #include <linux/iommu.h>
 #include <linux/delay.h>
@@ -2193,7 +2194,7 @@ static int amd_iommu_add_device(struct device *dev)
 				dev_name(dev));
 
 		iommu_ignore_device(dev);
-		dev->dma_ops = &nommu_dma_ops;
+		dev->dma_ops = &dma_direct_ops;
 		goto out;
 	}
 	init_iommu_group(dev);
@@ -2599,51 +2600,32 @@ static void *alloc_coherent(struct device *dev, size_t size,
 			    unsigned long attrs)
 {
 	u64 dma_mask = dev->coherent_dma_mask;
-	struct protection_domain *domain;
-	struct dma_ops_domain *dma_dom;
-	struct page *page;
-
-	domain = get_domain(dev);
-	if (PTR_ERR(domain) == -EINVAL) {
-		page = alloc_pages(flag, get_order(size));
-		*dma_addr = page_to_phys(page);
-		return page_address(page);
-	} else if (IS_ERR(domain))
-		return NULL;
+	struct protection_domain *domain = get_domain(dev);
+	bool is_direct = false;
+	void *virt_addr;
 
-	dma_dom   = to_dma_ops_domain(domain);
-	size	  = PAGE_ALIGN(size);
-	dma_mask  = dev->coherent_dma_mask;
-	flag     &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
-	flag     |= __GFP_ZERO;
-
-	page = alloc_pages(flag | __GFP_NOWARN,  get_order(size));
-	if (!page) {
-		if (!gfpflags_allow_blocking(flag))
-			return NULL;
-
-		page = dma_alloc_from_contiguous(dev, size >> PAGE_SHIFT,
-						 get_order(size), flag);
-		if (!page)
+	if (IS_ERR(domain)) {
+		if (PTR_ERR(domain) != -EINVAL)
 			return NULL;
+		is_direct = true;
 	}
 
+	virt_addr = dma_direct_alloc(dev, size, dma_addr, flag, attrs);
+	if (!virt_addr || is_direct)
+		return virt_addr;
+
 	if (!dma_mask)
 		dma_mask = *dev->dma_mask;
 
-	*dma_addr = __map_single(dev, dma_dom, page_to_phys(page),
-				 size, DMA_BIDIRECTIONAL, dma_mask);
-
+	*dma_addr = __map_single(dev, to_dma_ops_domain(domain),
+			virt_to_phys(virt_addr), PAGE_ALIGN(size),
+			DMA_BIDIRECTIONAL, dma_mask);
 	if (*dma_addr == AMD_IOMMU_MAPPING_ERROR)
 		goto out_free;
-
-	return page_address(page);
+	return virt_addr;
 
 out_free:
-
-	if (!dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT))
-		__free_pages(page, get_order(size));
-
+	dma_direct_free(dev, size, virt_addr, *dma_addr, attrs);
 	return NULL;
 }
 
@@ -2654,24 +2636,17 @@ static void free_coherent(struct device *dev, size_t size,
 			  void *virt_addr, dma_addr_t dma_addr,
 			  unsigned long attrs)
 {
-	struct protection_domain *domain;
-	struct dma_ops_domain *dma_dom;
-	struct page *page;
+	struct protection_domain *domain = get_domain(dev);
 
-	page = virt_to_page(virt_addr);
 	size = PAGE_ALIGN(size);
 
-	domain = get_domain(dev);
-	if (IS_ERR(domain))
-		goto free_mem;
+	if (!IS_ERR(domain)) {
+		struct dma_ops_domain *dma_dom = to_dma_ops_domain(domain);
 
-	dma_dom = to_dma_ops_domain(domain);
-
-	__unmap_single(dma_dom, dma_addr, size, DMA_BIDIRECTIONAL);
+		__unmap_single(dma_dom, dma_addr, size, DMA_BIDIRECTIONAL);
+	}
 
-free_mem:
-	if (!dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT))
-		__free_pages(page, get_order(size));
+	dma_direct_free(dev, size, virt_addr, dma_addr, attrs);
 }
 
 /*
@@ -2680,7 +2655,7 @@ static void free_coherent(struct device *dev, size_t size,
  */
 static int amd_iommu_dma_supported(struct device *dev, u64 mask)
 {
-	if (!x86_dma_supported(dev, mask))
+	if (!dma_direct_supported(dev, mask))
 		return 0;
 	return check_device(dev);
 }
@@ -2794,7 +2769,7 @@ int __init amd_iommu_init_dma_ops(void)
 	 * continue to be SWIOTLB.
 	 */
 	if (!swiotlb)
-		dma_ops = &nommu_dma_ops;
+		dma_ops = &dma_direct_ops;
 
 	if (amd_iommu_unmap_flush)
 		pr_info("AMD-Vi: IO/TLB flush on unmap enabled\n");

drivers/iommu/intel-iommu.c

@@ -31,6 +31,7 @@
 #include <linux/pci.h>
 #include <linux/dmar.h>
 #include <linux/dma-mapping.h>
+#include <linux/dma-direct.h>
 #include <linux/mempool.h>
 #include <linux/memory.h>
 #include <linux/cpu.h>
@@ -45,6 +46,7 @@
 #include <linux/pci-ats.h>
 #include <linux/memblock.h>
 #include <linux/dma-contiguous.h>
+#include <linux/dma-direct.h>
 #include <linux/crash_dump.h>
 #include <asm/irq_remapping.h>
 #include <asm/cacheflush.h>
@@ -3707,61 +3709,30 @@ static void *intel_alloc_coherent(struct device *dev, size_t size,
 				  dma_addr_t *dma_handle, gfp_t flags,
 				  unsigned long attrs)
 {
-	struct page *page = NULL;
-	int order;
+	void *vaddr;
 
-	size = PAGE_ALIGN(size);
-	order = get_order(size);
+	vaddr = dma_direct_alloc(dev, size, dma_handle, flags, attrs);
+	if (iommu_no_mapping(dev) || !vaddr)
+		return vaddr;
 
-	if (!iommu_no_mapping(dev))
-		flags &= ~(GFP_DMA | GFP_DMA32);
-	else if (dev->coherent_dma_mask < dma_get_required_mask(dev)) {
-		if (dev->coherent_dma_mask < DMA_BIT_MASK(32))
-			flags |= GFP_DMA;
-		else
-			flags |= GFP_DMA32;
-	}
-
-	if (gfpflags_allow_blocking(flags)) {
-		unsigned int count = size >> PAGE_SHIFT;
-
-		page = dma_alloc_from_contiguous(dev, count, order, flags);
-		if (page && iommu_no_mapping(dev) &&
-		    page_to_phys(page) + size > dev->coherent_dma_mask) {
-			dma_release_from_contiguous(dev, page, count);
-			page = NULL;
-		}
-	}
-
-	if (!page)
-		page = alloc_pages(flags, order);
-	if (!page)
-		return NULL;
-	memset(page_address(page), 0, size);
-
-	*dma_handle = __intel_map_single(dev, page_to_phys(page), size,
-					 DMA_BIDIRECTIONAL,
-					 dev->coherent_dma_mask);
-	if (*dma_handle)
-		return page_address(page);
-	if (!dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT))
-		__free_pages(page, order);
+	*dma_handle = __intel_map_single(dev, virt_to_phys(vaddr),
+			PAGE_ALIGN(size), DMA_BIDIRECTIONAL,
+			dev->coherent_dma_mask);
+	if (!*dma_handle)
+		goto out_free_pages;
+	return vaddr;
 
+out_free_pages:
+	dma_direct_free(dev, size, vaddr, *dma_handle, attrs);
 	return NULL;
 }
 
 static void intel_free_coherent(struct device *dev, size_t size, void *vaddr,
 				dma_addr_t dma_handle, unsigned long attrs)
 {
-	int order;
-	struct page *page = virt_to_page(vaddr);
-
-	size = PAGE_ALIGN(size);
-	order = get_order(size);
-
-	intel_unmap(dev, dma_handle, size);
-	if (!dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT))
-		__free_pages(page, order);
+	if (!iommu_no_mapping(dev))
+		intel_unmap(dev, dma_handle, PAGE_ALIGN(size));
+	dma_direct_free(dev, size, vaddr, dma_handle, attrs);
 }
 
 static void intel_unmap_sg(struct device *dev, struct scatterlist *sglist,
@@ -3871,7 +3842,7 @@ const struct dma_map_ops intel_dma_ops = {
 	.unmap_page = intel_unmap_page,
 	.mapping_error = intel_mapping_error,
 #ifdef CONFIG_X86
-	.dma_supported = x86_dma_supported,
+	.dma_supported = dma_direct_supported,
 #endif
 };
 

drivers/xen/swiotlb-xen.c

@@ -53,20 +53,6 @@
  * API.
  */
 
-#ifndef CONFIG_X86
-static unsigned long dma_alloc_coherent_mask(struct device *dev,
-					    gfp_t gfp)
-{
-	unsigned long dma_mask = 0;
-
-	dma_mask = dev->coherent_dma_mask;
-	if (!dma_mask)
-		dma_mask = (gfp & GFP_DMA) ? DMA_BIT_MASK(24) : DMA_BIT_MASK(32);
-
-	return dma_mask;
-}
-#endif
-
 #define XEN_SWIOTLB_ERROR_CODE	(~(dma_addr_t)0x0)
 
 static char *xen_io_tlb_start, *xen_io_tlb_end;
@@ -328,7 +314,7 @@ xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
 		return ret;
 
 	if (hwdev && hwdev->coherent_dma_mask)
-		dma_mask = dma_alloc_coherent_mask(hwdev, flags);
+		dma_mask = hwdev->coherent_dma_mask;
 
 	/* At this point dma_handle is the physical address, next we are
 	 * going to set it to the machine address.

include/linux/dma-direct.h

@@ -3,18 +3,19 @@
 #define _LINUX_DMA_DIRECT_H 1
 
 #include <linux/dma-mapping.h>
+#include <linux/mem_encrypt.h>
 
 #ifdef CONFIG_ARCH_HAS_PHYS_TO_DMA
 #include <asm/dma-direct.h>
 #else
-static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
+static inline dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr)
 {
 	dma_addr_t dev_addr = (dma_addr_t)paddr;
 
 	return dev_addr - ((dma_addr_t)dev->dma_pfn_offset << PAGE_SHIFT);
 }
 
-static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
+static inline phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t dev_addr)
 {
 	phys_addr_t paddr = (phys_addr_t)dev_addr;
 
@@ -30,6 +31,22 @@ static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
 }
 #endif /* !CONFIG_ARCH_HAS_PHYS_TO_DMA */
 
+/*
+ * If memory encryption is supported, phys_to_dma will set the memory encryption
+ * bit in the DMA address, and dma_to_phys will clear it.  The raw __phys_to_dma
+ * and __dma_to_phys versions should only be used on non-encrypted memory for
+ * special occasions like DMA coherent buffers.
+ */
+static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
+{
+	return __sme_set(__phys_to_dma(dev, paddr));
+}
+
+static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
+{
+	return __sme_clr(__dma_to_phys(dev, daddr));
+}
+
 #ifdef CONFIG_ARCH_HAS_DMA_MARK_CLEAN
 void dma_mark_clean(void *addr, size_t size);
 #else

include/linux/dma-mapping.h

@@ -518,12 +518,8 @@ static inline void *dma_alloc_attrs(struct device *dev, size_t size,
 	if (dma_alloc_from_dev_coherent(dev, size, dma_handle, &cpu_addr))
 		return cpu_addr;
 
-	/*
-	 * Let the implementation decide on the zone to allocate from, and
-	 * decide on the way of zeroing the memory given that the memory
-	 * returned should always be zeroed.
-	 */
-	flag &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM | __GFP_ZERO);
+	/* let the implementation decide on the zone to allocate from: */
+	flag &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
 
 	if (!arch_dma_alloc_attrs(&dev, &flag))
 		return NULL;

include/linux/set_memory.h

@@ -17,4 +17,16 @@ static inline int set_memory_x(unsigned long addr,  int numpages) { return 0; }
 static inline int set_memory_nx(unsigned long addr, int numpages) { return 0; }
 #endif
 
+#ifndef CONFIG_ARCH_HAS_MEM_ENCRYPT
+static inline int set_memory_encrypted(unsigned long addr, int numpages)
+{
+	return 0;
+}
+
+static inline int set_memory_decrypted(unsigned long addr, int numpages)
+{
+	return 0;
+}
+#endif /* CONFIG_ARCH_HAS_MEM_ENCRYPT */
+
 #endif /* _LINUX_SET_MEMORY_H_ */

include/linux/swiotlb.h

@@ -72,14 +72,6 @@ void *swiotlb_alloc(struct device *hwdev, size_t size, dma_addr_t *dma_handle,
 void swiotlb_free(struct device *dev, size_t size, void *vaddr,
 		dma_addr_t dma_addr, unsigned long attrs);
 
-extern void
-*swiotlb_alloc_coherent(struct device *hwdev, size_t size,
-			dma_addr_t *dma_handle, gfp_t flags);
-
-extern void
-swiotlb_free_coherent(struct device *hwdev, size_t size,
-		      void *vaddr, dma_addr_t dma_handle);
-
 extern dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
 				   unsigned long offset, size_t size,
 				   enum dma_data_direction dir,

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 +57,10 @@ 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;
+
+	/* we always manually zero the memory once we are done: */
+	gfp &= ~__GFP_ZERO;
 
 	/* 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 +93,15 @@ void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
 
 	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 +112,12 @@ 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,

lib/swiotlb.c

@@ -31,6 +31,7 @@
 #include <linux/gfp.h>
 #include <linux/scatterlist.h>
 #include <linux/mem_encrypt.h>
+#include <linux/set_memory.h>
 
 #include <asm/io.h>
 #include <asm/dma.h>
@@ -156,22 +157,6 @@ unsigned long swiotlb_size_or_default(void)
 	return size ? size : (IO_TLB_DEFAULT_SIZE);
 }
 
-void __weak swiotlb_set_mem_attributes(void *vaddr, unsigned long size) { }
-
-/* For swiotlb, clear memory encryption mask from dma addresses */
-static dma_addr_t swiotlb_phys_to_dma(struct device *hwdev,
-				      phys_addr_t address)
-{
-	return __sme_clr(phys_to_dma(hwdev, address));
-}
-
-/* Note that this doesn't work with highmem page */
-static dma_addr_t swiotlb_virt_to_bus(struct device *hwdev,
-				      volatile void *address)
-{
-	return phys_to_dma(hwdev, virt_to_phys(address));
-}
-
 static bool no_iotlb_memory;
 
 void swiotlb_print_info(void)
@@ -209,12 +194,12 @@ void __init swiotlb_update_mem_attributes(void)
 
 	vaddr = phys_to_virt(io_tlb_start);
 	bytes = PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT);
-	swiotlb_set_mem_attributes(vaddr, bytes);
+	set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT);
 	memset(vaddr, 0, bytes);
 
 	vaddr = phys_to_virt(io_tlb_overflow_buffer);
 	bytes = PAGE_ALIGN(io_tlb_overflow);
-	swiotlb_set_mem_attributes(vaddr, bytes);
+	set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT);
 	memset(vaddr, 0, bytes);
 }
 
@@ -355,7 +340,7 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
 	io_tlb_start = virt_to_phys(tlb);
 	io_tlb_end = io_tlb_start + bytes;
 
-	swiotlb_set_mem_attributes(tlb, bytes);
+	set_memory_decrypted((unsigned long)tlb, bytes >> PAGE_SHIFT);
 	memset(tlb, 0, bytes);
 
 	/*
@@ -366,7 +351,8 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
 	if (!v_overflow_buffer)
 		goto cleanup2;
 
-	swiotlb_set_mem_attributes(v_overflow_buffer, io_tlb_overflow);
+	set_memory_decrypted((unsigned long)v_overflow_buffer,
+			io_tlb_overflow >> PAGE_SHIFT);
 	memset(v_overflow_buffer, 0, io_tlb_overflow);
 	io_tlb_overflow_buffer = virt_to_phys(v_overflow_buffer);
 
@@ -622,7 +608,7 @@ map_single(struct device *hwdev, phys_addr_t phys, size_t size,
 		return SWIOTLB_MAP_ERROR;
 	}
 
-	start_dma_addr = swiotlb_phys_to_dma(hwdev, io_tlb_start);
+	start_dma_addr = __phys_to_dma(hwdev, io_tlb_start);
 	return swiotlb_tbl_map_single(hwdev, start_dma_addr, phys, size,
 				      dir, attrs);
 }
@@ -706,6 +692,7 @@ void swiotlb_tbl_sync_single(struct device *hwdev, phys_addr_t tlb_addr,
 	}
 }
 
+#ifdef CONFIG_DMA_DIRECT_OPS
 static inline bool dma_coherent_ok(struct device *dev, dma_addr_t addr,
 		size_t size)
 {
@@ -726,12 +713,12 @@ swiotlb_alloc_buffer(struct device *dev, size_t size, dma_addr_t *dma_handle,
 		goto out_warn;
 
 	phys_addr = swiotlb_tbl_map_single(dev,
-			swiotlb_phys_to_dma(dev, io_tlb_start),
+			__phys_to_dma(dev, io_tlb_start),
 			0, size, DMA_FROM_DEVICE, 0);
 	if (phys_addr == SWIOTLB_MAP_ERROR)
 		goto out_warn;
 
-	*dma_handle = swiotlb_phys_to_dma(dev, phys_addr);
+	*dma_handle = __phys_to_dma(dev, phys_addr);
 	if (dma_coherent_ok(dev, *dma_handle, size))
 		goto out_unmap;
 
@@ -759,28 +746,6 @@ swiotlb_alloc_buffer(struct device *dev, size_t size, dma_addr_t *dma_handle,
 	return NULL;
 }
 
-void *
-swiotlb_alloc_coherent(struct device *hwdev, size_t size,
-		       dma_addr_t *dma_handle, gfp_t flags)
-{
-	int order = get_order(size);
-	unsigned long attrs = (flags & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0;
-	void *ret;
-
-	ret = (void *)__get_free_pages(flags, order);
-	if (ret) {
-		*dma_handle = swiotlb_virt_to_bus(hwdev, ret);
-		if (dma_coherent_ok(hwdev, *dma_handle, size)) {
-			memset(ret, 0, size);
-			return ret;
-		}
-		free_pages((unsigned long)ret, order);
-	}
-
-	return swiotlb_alloc_buffer(hwdev, size, dma_handle, attrs);
-}
-EXPORT_SYMBOL(swiotlb_alloc_coherent);
-
 static bool swiotlb_free_buffer(struct device *dev, size_t size,
 		dma_addr_t dma_addr)
 {
@@ -799,15 +764,7 @@ static bool swiotlb_free_buffer(struct device *dev, size_t size,
 				 DMA_ATTR_SKIP_CPU_SYNC);
 	return true;
 }
-
-void
-swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr,
-		      dma_addr_t dev_addr)
-{
-	if (!swiotlb_free_buffer(hwdev, size, dev_addr))
-		free_pages((unsigned long)vaddr, get_order(size));
-}
-EXPORT_SYMBOL(swiotlb_free_coherent);
+#endif
 
 static void
 swiotlb_full(struct device *dev, size_t size, enum dma_data_direction dir,
@@ -867,10 +824,10 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
 	map = map_single(dev, phys, size, dir, attrs);
 	if (map == SWIOTLB_MAP_ERROR) {
 		swiotlb_full(dev, size, dir, 1);
-		return swiotlb_phys_to_dma(dev, io_tlb_overflow_buffer);
+		return __phys_to_dma(dev, io_tlb_overflow_buffer);
 	}
 
-	dev_addr = swiotlb_phys_to_dma(dev, map);
+	dev_addr = __phys_to_dma(dev, map);
 
 	/* Ensure that the address returned is DMA'ble */
 	if (dma_capable(dev, dev_addr, size))
@@ -879,7 +836,7 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
 	attrs |= DMA_ATTR_SKIP_CPU_SYNC;
 	swiotlb_tbl_unmap_single(dev, map, size, dir, attrs);
 
-	return swiotlb_phys_to_dma(dev, io_tlb_overflow_buffer);
+	return __phys_to_dma(dev, io_tlb_overflow_buffer);
 }
 
 /*
@@ -1009,7 +966,7 @@ swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems,
 				sg_dma_len(sgl) = 0;
 				return 0;
 			}
-			sg->dma_address = swiotlb_phys_to_dma(hwdev, map);
+			sg->dma_address = __phys_to_dma(hwdev, map);
 		} else
 			sg->dma_address = dev_addr;
 		sg_dma_len(sg) = sg->length;
@@ -1073,7 +1030,7 @@ swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
 int
 swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr)
 {
-	return (dma_addr == swiotlb_phys_to_dma(hwdev, io_tlb_overflow_buffer));
+	return (dma_addr == __phys_to_dma(hwdev, io_tlb_overflow_buffer));
 }
 
 /*
@@ -1085,7 +1042,7 @@ swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr)
 int
 swiotlb_dma_supported(struct device *hwdev, u64 mask)
 {
-	return swiotlb_phys_to_dma(hwdev, io_tlb_end - 1) <= mask;
+	return __phys_to_dma(hwdev, io_tlb_end - 1) <= mask;
 }
 
 #ifdef CONFIG_DMA_DIRECT_OPS