force_dma_unencrypted() has to return true for KVM guest with the memory protected enabled. Move it out of AMD SME code. Introduce new config option X86_MEM_ENCRYPT_COMMON that has to be selected by all x86 memory encryption features. This is preparation for the following patches. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> --- arch/x86/Kconfig | 8 +++++-- arch/x86/include/asm/io.h | 4 +++- arch/x86/mm/Makefile | 2 ++ arch/x86/mm/mem_encrypt.c | 30 ------------------------- arch/x86/mm/mem_encrypt_common.c | 38 ++++++++++++++++++++++++++++++++ 5 files changed, 49 insertions(+), 33 deletions(-) create mode 100644 arch/x86/mm/mem_encrypt_common.c diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 7101ac64bb20..619ebf40e457 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1514,13 +1514,17 @@ config X86_CPA_STATISTICS helps to determine the effectiveness of preserving large and huge page mappings when mapping protections are changed. +config X86_MEM_ENCRYPT_COMMON + select ARCH_HAS_FORCE_DMA_UNENCRYPTED + select DYNAMIC_PHYSICAL_MASK + def_bool n + config AMD_MEM_ENCRYPT bool "AMD Secure Memory Encryption (SME) support" depends on X86_64 && CPU_SUP_AMD select DMA_COHERENT_POOL - select DYNAMIC_PHYSICAL_MASK select ARCH_USE_MEMREMAP_PROT - select ARCH_HAS_FORCE_DMA_UNENCRYPTED + select X86_MEM_ENCRYPT_COMMON help Say yes to enable support for the encryption of system memory. This requires an AMD processor that supports Secure Memory diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h index e1aa17a468a8..c58d52fd7bf2 100644 --- a/arch/x86/include/asm/io.h +++ b/arch/x86/include/asm/io.h @@ -256,10 +256,12 @@ static inline void slow_down_io(void) #endif -#ifdef CONFIG_AMD_MEM_ENCRYPT #include <linux/jump_label.h> extern struct static_key_false sev_enable_key; + +#ifdef CONFIG_AMD_MEM_ENCRYPT + static inline bool sev_key_active(void) { return static_branch_unlikely(&sev_enable_key); diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile index 5864219221ca..b31cb52bf1bd 100644 --- a/arch/x86/mm/Makefile +++ b/arch/x86/mm/Makefile @@ -52,6 +52,8 @@ obj-$(CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS) += pkeys.o obj-$(CONFIG_RANDOMIZE_MEMORY) += kaslr.o obj-$(CONFIG_PAGE_TABLE_ISOLATION) += pti.o +obj-$(CONFIG_X86_MEM_ENCRYPT_COMMON) += mem_encrypt_common.o + obj-$(CONFIG_AMD_MEM_ENCRYPT) += mem_encrypt.o obj-$(CONFIG_AMD_MEM_ENCRYPT) += mem_encrypt_identity.o obj-$(CONFIG_AMD_MEM_ENCRYPT) += mem_encrypt_boot.o diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c index 9f1177edc2e7..4dbdc9dac36b 100644 --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -15,10 +15,6 @@ #include <linux/dma-direct.h> #include <linux/swiotlb.h> #include <linux/mem_encrypt.h> -#include <linux/device.h> -#include <linux/kernel.h> -#include <linux/bitops.h> -#include <linux/dma-mapping.h> #include <asm/tlbflush.h> #include <asm/fixmap.h> @@ -350,32 +346,6 @@ bool sev_active(void) return sme_me_mask && sev_enabled; } -/* Override for DMA direct allocation check - ARCH_HAS_FORCE_DMA_UNENCRYPTED */ -bool force_dma_unencrypted(struct device *dev) -{ - /* - * For SEV, all DMA must be to unencrypted addresses. - */ - if (sev_active()) - return true; - - /* - * For SME, all DMA must be to unencrypted addresses if the - * device does not support DMA to addresses that include the - * encryption mask. - */ - if (sme_active()) { - u64 dma_enc_mask = DMA_BIT_MASK(__ffs64(sme_me_mask)); - u64 dma_dev_mask = min_not_zero(dev->coherent_dma_mask, - dev->bus_dma_limit); - - if (dma_dev_mask <= dma_enc_mask) - return true; - } - - return false; -} - void __init mem_encrypt_free_decrypted_mem(void) { unsigned long vaddr, vaddr_end, npages; diff --git a/arch/x86/mm/mem_encrypt_common.c b/arch/x86/mm/mem_encrypt_common.c new file mode 100644 index 000000000000..964e04152417 --- /dev/null +++ b/arch/x86/mm/mem_encrypt_common.c @@ -0,0 +1,38 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * AMD Memory Encryption Support + * + * Copyright (C) 2016 Advanced Micro Devices, Inc. + * + * Author: Tom Lendacky <thomas.lendacky@xxxxxxx> + */ + +#include <linux/mm.h> +#include <linux/mem_encrypt.h> +#include <linux/dma-mapping.h> + +/* Override for DMA direct allocation check - ARCH_HAS_FORCE_DMA_UNENCRYPTED */ +bool force_dma_unencrypted(struct device *dev) +{ + /* + * For SEV, all DMA must be to unencrypted/shared addresses. + */ + if (sev_active()) + return true; + + /* + * For SME, all DMA must be to unencrypted addresses if the + * device does not support DMA to addresses that include the + * encryption mask. + */ + if (sme_active()) { + u64 dma_enc_mask = DMA_BIT_MASK(__ffs64(sme_me_mask)); + u64 dma_dev_mask = min_not_zero(dev->coherent_dma_mask, + dev->bus_dma_limit); + + if (dma_dev_mask <= dma_enc_mask) + return true; + } + + return false; +} -- 2.26.2