From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f197.google.com (mail-pf0-f197.google.com [209.85.192.197]) by kanga.kvack.org (Postfix) with ESMTP id 8D72E6B0497 for ; Mon, 17 Jul 2017 17:11:38 -0400 (EDT) Received: by mail-pf0-f197.google.com with SMTP id s70so1814073pfs.5 for ; Mon, 17 Jul 2017 14:11:38 -0700 (PDT) Received: from NAM01-BN3-obe.outbound.protection.outlook.com (mail-bn3nam01on0053.outbound.protection.outlook.com. [104.47.33.53]) by mx.google.com with ESMTPS id v66si176638pfv.303.2017.07.17.14.11.36 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 17 Jul 2017 14:11:37 -0700 (PDT) From: Tom Lendacky Subject: [PATCH v10 12/38] x86/mm: Extend early_memremap() support with additional attrs Date: Mon, 17 Jul 2017 16:10:09 -0500 Message-Id: <479b5832c30fae3efa7932e48f81794e86397229.1500319216.git.thomas.lendacky@amd.com> In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: To: x86@kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-efi@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, kvm@vger.kernel.org, kasan-dev@googlegroups.com Cc: =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Arnd Bergmann , Jonathan Corbet , Matt Fleming , Konrad Rzeszutek Wilk , Andrey Ryabinin , Ingo Molnar , Borislav Petkov , Andy Lutomirski , "H. Peter Anvin" , Paolo Bonzini , Alexander Potapenko , Thomas Gleixner , Dmitry Vyukov , Rik van Riel , Larry Woodman , Dave Young , Toshimitsu Kani , "Michael S. Tsirkin" , Brijesh Singh Add early_memremap() support to be able to specify encrypted and decrypted mappings with and without write-protection. The use of write-protection is necessary when encrypting data "in place". The write-protect attribute is considered cacheable for loads, but not stores. This implies that the hardware will never give the core a dirty line with this memtype. Reviewed-by: Borislav Petkov Signed-off-by: Tom Lendacky --- arch/x86/Kconfig | 4 ++++ arch/x86/include/asm/fixmap.h | 13 +++++++++++ arch/x86/include/asm/pgtable_types.h | 8 +++++++ arch/x86/mm/ioremap.c | 44 ++++++++++++++++++++++++++++++++++++ include/asm-generic/early_ioremap.h | 2 ++ mm/early_ioremap.c | 10 ++++++++ 6 files changed, 81 insertions(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index ba7b93d..8328bcb 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1440,6 +1440,10 @@ config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT If set to N, then the encryption of system memory can be activated with the mem_encrypt=on command line option. +config ARCH_USE_MEMREMAP_PROT + def_bool y + depends on AMD_MEM_ENCRYPT + # Common NUMA Features config NUMA bool "Numa Memory Allocation and Scheduler Support" diff --git a/arch/x86/include/asm/fixmap.h b/arch/x86/include/asm/fixmap.h index d9ff226..dcd9fb5 100644 --- a/arch/x86/include/asm/fixmap.h +++ b/arch/x86/include/asm/fixmap.h @@ -164,6 +164,19 @@ static inline void __set_fixmap(enum fixed_addresses idx, */ #define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_IO_NOCACHE +/* + * Early memremap routines used for in-place encryption. The mappings created + * by these routines are intended to be used as temporary mappings. + */ +void __init *early_memremap_encrypted(resource_size_t phys_addr, + unsigned long size); +void __init *early_memremap_encrypted_wp(resource_size_t phys_addr, + unsigned long size); +void __init *early_memremap_decrypted(resource_size_t phys_addr, + unsigned long size); +void __init *early_memremap_decrypted_wp(resource_size_t phys_addr, + unsigned long size); + #include #define __late_set_fixmap(idx, phys, flags) __set_fixmap(idx, phys, flags) diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index de32ca3..32095af 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -161,6 +161,7 @@ enum page_cache_mode { #define _PAGE_CACHE_MASK (_PAGE_PAT | _PAGE_PCD | _PAGE_PWT) #define _PAGE_NOCACHE (cachemode2protval(_PAGE_CACHE_MODE_UC)) +#define _PAGE_CACHE_WP (cachemode2protval(_PAGE_CACHE_MODE_WP)) #define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED) #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | \ @@ -189,6 +190,7 @@ enum page_cache_mode { #define __PAGE_KERNEL_VVAR (__PAGE_KERNEL_RO | _PAGE_USER) #define __PAGE_KERNEL_LARGE (__PAGE_KERNEL | _PAGE_PSE) #define __PAGE_KERNEL_LARGE_EXEC (__PAGE_KERNEL_EXEC | _PAGE_PSE) +#define __PAGE_KERNEL_WP (__PAGE_KERNEL | _PAGE_CACHE_WP) #define __PAGE_KERNEL_IO (__PAGE_KERNEL) #define __PAGE_KERNEL_IO_NOCACHE (__PAGE_KERNEL_NOCACHE) @@ -202,6 +204,12 @@ enum page_cache_mode { #define _KERNPG_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | \ _PAGE_DIRTY | _PAGE_ENC) +#define __PAGE_KERNEL_ENC (__PAGE_KERNEL | _PAGE_ENC) +#define __PAGE_KERNEL_ENC_WP (__PAGE_KERNEL_WP | _PAGE_ENC) + +#define __PAGE_KERNEL_NOENC (__PAGE_KERNEL) +#define __PAGE_KERNEL_NOENC_WP (__PAGE_KERNEL_WP) + #define PAGE_KERNEL __pgprot(__PAGE_KERNEL | _PAGE_ENC) #define PAGE_KERNEL_RO __pgprot(__PAGE_KERNEL_RO | _PAGE_ENC) #define PAGE_KERNEL_EXEC __pgprot(__PAGE_KERNEL_EXEC | _PAGE_ENC) diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index 66ddf5e..570201b 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -417,6 +417,50 @@ void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr) iounmap((void __iomem *)((unsigned long)addr & PAGE_MASK)); } +#ifdef CONFIG_ARCH_USE_MEMREMAP_PROT +/* Remap memory with encryption */ +void __init *early_memremap_encrypted(resource_size_t phys_addr, + unsigned long size) +{ + return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_ENC); +} + +/* + * Remap memory with encryption and write-protected - cannot be called + * before pat_init() is called + */ +void __init *early_memremap_encrypted_wp(resource_size_t phys_addr, + unsigned long size) +{ + /* Be sure the write-protect PAT entry is set for write-protect */ + if (__pte2cachemode_tbl[_PAGE_CACHE_MODE_WP] != _PAGE_CACHE_MODE_WP) + return NULL; + + return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_ENC_WP); +} + +/* Remap memory without encryption */ +void __init *early_memremap_decrypted(resource_size_t phys_addr, + unsigned long size) +{ + return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_NOENC); +} + +/* + * Remap memory without encryption and write-protected - cannot be called + * before pat_init() is called + */ +void __init *early_memremap_decrypted_wp(resource_size_t phys_addr, + unsigned long size) +{ + /* Be sure the write-protect PAT entry is set for write-protect */ + if (__pte2cachemode_tbl[_PAGE_CACHE_MODE_WP] != _PAGE_CACHE_MODE_WP) + return NULL; + + return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_NOENC_WP); +} +#endif /* CONFIG_ARCH_USE_MEMREMAP_PROT */ + static pte_t bm_pte[PAGE_SIZE/sizeof(pte_t)] __page_aligned_bss; static inline pmd_t * __init early_ioremap_pmd(unsigned long addr) diff --git a/include/asm-generic/early_ioremap.h b/include/asm-generic/early_ioremap.h index 734ad4d..2edef8d 100644 --- a/include/asm-generic/early_ioremap.h +++ b/include/asm-generic/early_ioremap.h @@ -13,6 +13,8 @@ extern void *early_memremap(resource_size_t phys_addr, unsigned long size); extern void *early_memremap_ro(resource_size_t phys_addr, unsigned long size); +extern void *early_memremap_prot(resource_size_t phys_addr, + unsigned long size, unsigned long prot_val); extern void early_iounmap(void __iomem *addr, unsigned long size); extern void early_memunmap(void *addr, unsigned long size); diff --git a/mm/early_ioremap.c b/mm/early_ioremap.c index 6d5717b..d7d30da 100644 --- a/mm/early_ioremap.c +++ b/mm/early_ioremap.c @@ -226,6 +226,16 @@ void __init early_iounmap(void __iomem *addr, unsigned long size) } #endif +#ifdef CONFIG_ARCH_USE_MEMREMAP_PROT +void __init * +early_memremap_prot(resource_size_t phys_addr, unsigned long size, + unsigned long prot_val) +{ + return (__force void *)__early_ioremap(phys_addr, size, + __pgprot(prot_val)); +} +#endif + #define MAX_MAP_CHUNK (NR_FIX_BTMAPS << PAGE_SHIFT) void __init copy_from_early_mem(void *dest, phys_addr_t src, unsigned long size) -- 1.9.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org