Re: [PATCH 12/14] dma-direct: handle the memory encryption bit in common code
From: Tom Lendacky
Date: Mon Mar 19 2018 - 10:50:51 EST
On 3/19/2018 5:38 AM, Christoph Hellwig wrote:
> Give the basic phys_to_dma and dma_to_phys helpers a __-prefix and add
> the memory encryption mask to the non-prefixed versions. Use the
> __-prefixed versions directly instead of clearing the mask again in
> various places.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
> ---
> arch/arm/include/asm/dma-direct.h | 4 ++--
> arch/mips/cavium-octeon/dma-octeon.c | 10 ++++-----
> .../include/asm/mach-cavium-octeon/dma-coherence.h | 4 ++--
> .../include/asm/mach-loongson64/dma-coherence.h | 10 ++++-----
> arch/mips/loongson64/common/dma-swiotlb.c | 4 ++--
> arch/powerpc/include/asm/dma-direct.h | 4 ++--
> arch/x86/Kconfig | 2 +-
> arch/x86/include/asm/dma-direct.h | 25 ++--------------------
> arch/x86/mm/mem_encrypt.c | 2 +-
> arch/x86/pci/sta2x11-fixup.c | 6 +++---
> include/linux/dma-direct.h | 21 ++++++++++++++++--
> lib/swiotlb.c | 25 ++++++++--------------
> 12 files changed, 53 insertions(+), 64 deletions(-)
>
> diff --git a/arch/arm/include/asm/dma-direct.h b/arch/arm/include/asm/dma-direct.h
> index 5b0a8a421894..b67e5fc1fe43 100644
> --- a/arch/arm/include/asm/dma-direct.h
> +++ b/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;
> diff --git a/arch/mips/cavium-octeon/dma-octeon.c b/arch/mips/cavium-octeon/dma-octeon.c
> index c7bb8a407041..7b335ab21697 100644
> --- a/arch/mips/cavium-octeon/dma-octeon.c
> +++ b/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 = {
> diff --git a/arch/mips/include/asm/mach-cavium-octeon/dma-coherence.h b/arch/mips/include/asm/mach-cavium-octeon/dma-coherence.h
> index 138edf6b5b48..6eb1ee548b11 100644
> --- a/arch/mips/include/asm/mach-cavium-octeon/dma-coherence.h
> +++ b/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;
> diff --git a/arch/mips/include/asm/mach-loongson64/dma-coherence.h b/arch/mips/include/asm/mach-loongson64/dma-coherence.h
> index b1b575f5c6c1..64fc44dec0a8 100644
> --- a/arch/mips/include/asm/mach-loongson64/dma-coherence.h
> +++ b/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
> diff --git a/arch/mips/loongson64/common/dma-swiotlb.c b/arch/mips/loongson64/common/dma-swiotlb.c
> index 7bbcf89475f3..6a739f8ae110 100644
> --- a/arch/mips/loongson64/common/dma-swiotlb.c
> +++ b/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
> diff --git a/arch/powerpc/include/asm/dma-direct.h b/arch/powerpc/include/asm/dma-direct.h
> index a5b59c765426..7702875aabb7 100644
> --- a/arch/powerpc/include/asm/dma-direct.h
> +++ b/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);
> }
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 10f482beda1b..1ca4f0874517 100644
> --- a/arch/x86/Kconfig
> +++ b/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
> @@ -692,6 +691,7 @@ 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
> diff --git a/arch/x86/include/asm/dma-direct.h b/arch/x86/include/asm/dma-direct.h
> index 1295bc622ebe..1a19251eaac9 100644
> --- a/arch/x86/include/asm/dma-direct.h
> +++ b/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 */
> diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
> index d3b80d5f9828..1a05bea831a8 100644
> --- a/arch/x86/mm/mem_encrypt.c
> +++ b/arch/x86/mm/mem_encrypt.c
> @@ -216,7 +216,7 @@ static void *sev_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
> * 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)));
> + addr = __phys_to_dma(dev, page_to_phys(page));
> if ((addr + size) > dev->coherent_dma_mask) {
> __free_pages(page, get_order(size));
> } else {
> diff --git a/arch/x86/pci/sta2x11-fixup.c b/arch/x86/pci/sta2x11-fixup.c
> index eac58e03f43c..7a5bafb76d77 100644
> --- a/arch/x86/pci/sta2x11-fixup.c
> +++ b/arch/x86/pci/sta2x11-fixup.c
> @@ -207,11 +207,11 @@ 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->archdata.is_sta2x11)
> return paddr;
> @@ -223,7 +223,7 @@ 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->archdata.is_sta2x11)
> return daddr;
> diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h
> index bcdb1a3e4b1f..53ad6a47f513 100644
> --- a/include/linux/dma-direct.h
> +++ b/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
> diff --git a/lib/swiotlb.c b/lib/swiotlb.c
> index 005d1d87bb2e..8b06b4485e65 100644
> --- a/lib/swiotlb.c
> +++ b/lib/swiotlb.c
> @@ -157,13 +157,6 @@ unsigned long swiotlb_size_or_default(void)
> return size ? size : (IO_TLB_DEFAULT_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)
> @@ -622,7 +615,7 @@ 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);
> }
> @@ -726,12 +719,12 @@ 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;
>
> @@ -867,10 +860,10 @@ 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 +872,7 @@ 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 +1002,7 @@ 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 +1066,7 @@ 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 +1078,7 @@ 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
>