From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Lendacky Subject: [RFC PATCH v3 11/20] x86: Add support for changing memory encryption attribute Date: Wed, 9 Nov 2016 18:36:55 -0600 Message-ID: <20161110003655.3280.57333.stgit@tlendack-t1.amdoffice.net> References: <20161110003426.3280.2999.stgit@tlendack-t1.amdoffice.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20161110003426.3280.2999.stgit-qCXWGYdRb2BnqfbPTmsdiZQ+2ll4COg0XqFh9Ls21Oc@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: linux-arch-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, kasan-dev-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Cc: Rik van Riel , Thomas Gleixner , Arnd Bergmann , Jonathan Corbet , Matt Fleming , Radim =?utf-8?b?S3LEjW3DocWZ?= , Andrey Ryabinin , Ingo Molnar , Borislav Petkov , Andy Lutomirski , "H. Peter Anvin" , Paolo Bonzini , Alexander Potapenko , Larry Woodman , Dmitry Vyukov List-Id: linux-efi@vger.kernel.org This patch adds support to be change the memory encryption attribute for one or more memory pages. Signed-off-by: Tom Lendacky --- arch/x86/include/asm/cacheflush.h | 3 + arch/x86/include/asm/mem_encrypt.h | 13 ++++++ arch/x86/mm/mem_encrypt.c | 43 +++++++++++++++++++++ arch/x86/mm/pageattr.c | 73 ++++++++++++++++++++++++++++++++++++ 4 files changed, 132 insertions(+) diff --git a/arch/x86/include/asm/cacheflush.h b/arch/x86/include/asm/cacheflush.h index 61518cf..bfb08e5 100644 --- a/arch/x86/include/asm/cacheflush.h +++ b/arch/x86/include/asm/cacheflush.h @@ -13,6 +13,7 @@ * Executability : eXeutable, NoteXecutable * Read/Write : ReadOnly, ReadWrite * Presence : NotPresent + * Encryption : ENCrypted, DECrypted * * Within a category, the attributes are mutually exclusive. * @@ -48,6 +49,8 @@ int set_memory_ro(unsigned long addr, int numpages); int set_memory_rw(unsigned long addr, int numpages); int set_memory_np(unsigned long addr, int numpages); int set_memory_4k(unsigned long addr, int numpages); +int set_memory_enc(unsigned long addr, int numpages); +int set_memory_dec(unsigned long addr, int numpages); int set_memory_array_uc(unsigned long *addr, int addrinarray); int set_memory_array_wc(unsigned long *addr, int addrinarray); diff --git a/arch/x86/include/asm/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h index 0b40f79..d544481 100644 --- a/arch/x86/include/asm/mem_encrypt.h +++ b/arch/x86/include/asm/mem_encrypt.h @@ -21,6 +21,9 @@ extern unsigned long sme_me_mask; +int sme_set_mem_enc(void *vaddr, unsigned long size); +int sme_set_mem_unenc(void *vaddr, unsigned long size); + void __init sme_early_mem_enc(resource_size_t paddr, unsigned long size); void __init sme_early_mem_dec(resource_size_t paddr, @@ -39,6 +42,16 @@ void __init sme_early_init(void); #define sme_me_mask 0UL +static inline int sme_set_mem_enc(void *vaddr, unsigned long size) +{ + return 0; +} + +static inline int sme_set_mem_unenc(void *vaddr, unsigned long size) +{ + return 0; +} + static inline void __init sme_early_mem_enc(resource_size_t paddr, unsigned long size) { diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c index 411210d..41cfdf9 100644 --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -18,6 +18,7 @@ #include #include #include +#include extern pmdval_t early_pmd_flags; int __init __early_make_pgtable(unsigned long, pmdval_t); @@ -33,6 +34,48 @@ EXPORT_SYMBOL_GPL(sme_me_mask); /* Buffer used for early in-place encryption by BSP, no locking needed */ static char sme_early_buffer[PAGE_SIZE] __aligned(PAGE_SIZE); +int sme_set_mem_enc(void *vaddr, unsigned long size) +{ + unsigned long addr, numpages; + + if (!sme_me_mask) + return 0; + + addr = (unsigned long)vaddr & PAGE_MASK; + numpages = PAGE_ALIGN(size) >> PAGE_SHIFT; + + /* + * The set_memory_xxx functions take an integer for numpages, make + * sure it doesn't exceed that. + */ + if (numpages > INT_MAX) + return -EINVAL; + + return set_memory_enc(addr, numpages); +} +EXPORT_SYMBOL_GPL(sme_set_mem_enc); + +int sme_set_mem_unenc(void *vaddr, unsigned long size) +{ + unsigned long addr, numpages; + + if (!sme_me_mask) + return 0; + + addr = (unsigned long)vaddr & PAGE_MASK; + numpages = PAGE_ALIGN(size) >> PAGE_SHIFT; + + /* + * The set_memory_xxx functions take an integer for numpages, make + * sure it doesn't exceed that. + */ + if (numpages > INT_MAX) + return -EINVAL; + + return set_memory_dec(addr, numpages); +} +EXPORT_SYMBOL_GPL(sme_set_mem_unenc); + /* * This routine does not change the underlying encryption setting of the * page(s) that map this memory. It assumes that eventually the memory is diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index b8e6bb5..babf3a6 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -1729,6 +1729,79 @@ int set_memory_4k(unsigned long addr, int numpages) __pgprot(0), 1, 0, NULL); } +static int __set_memory_enc_dec(struct cpa_data *cpa) +{ + unsigned long addr; + int numpages; + int ret; + + /* People should not be passing in unaligned addresses */ + if (WARN_ONCE(*cpa->vaddr & ~PAGE_MASK, + "misaligned address: %#lx\n", *cpa->vaddr)) + *cpa->vaddr &= PAGE_MASK; + + addr = *cpa->vaddr; + numpages = cpa->numpages; + + /* Must avoid aliasing mappings in the highmem code */ + kmap_flush_unused(); + vm_unmap_aliases(); + + ret = __change_page_attr_set_clr(cpa, 1); + + /* Check whether we really changed something */ + if (!(cpa->flags & CPA_FLUSHTLB)) + goto out; + + /* + * On success we use CLFLUSH, when the CPU supports it to + * avoid the WBINVD. + */ + if (!ret && static_cpu_has(X86_FEATURE_CLFLUSH)) + cpa_flush_range(addr, numpages, 1); + else + cpa_flush_all(1); + +out: + return ret; +} + +int set_memory_enc(unsigned long addr, int numpages) +{ + struct cpa_data cpa; + + if (!sme_me_mask) + return 0; + + memset(&cpa, 0, sizeof(cpa)); + cpa.vaddr = &addr; + cpa.numpages = numpages; + cpa.mask_set = __pgprot(_PAGE_ENC); + cpa.mask_clr = __pgprot(0); + cpa.pgd = init_mm.pgd; + + return __set_memory_enc_dec(&cpa); +} +EXPORT_SYMBOL(set_memory_enc); + +int set_memory_dec(unsigned long addr, int numpages) +{ + struct cpa_data cpa; + + if (!sme_me_mask) + return 0; + + memset(&cpa, 0, sizeof(cpa)); + cpa.vaddr = &addr; + cpa.numpages = numpages; + cpa.mask_set = __pgprot(0); + cpa.mask_clr = __pgprot(_PAGE_ENC); + cpa.pgd = init_mm.pgd; + + return __set_memory_enc_dec(&cpa); +} +EXPORT_SYMBOL(set_memory_dec); + int set_pages_uc(struct page *page, int numpages) { unsigned long addr = (unsigned long)page_address(page);