| Message ID | f9951644147e27772bf4512325e8ba6472e363b7.1631141919.git.thomas.lendacky@amd.com |
|---|---|
| State | New |
| Headers | show |
| Series | Implement generic cc_platform_has() helper function | expand |
On Wed, Sep 08, 2021 at 05:58:34PM -0500, Tom Lendacky wrote: > diff --git a/arch/x86/kernel/cc_platform.c b/arch/x86/kernel/cc_platform.c > new file mode 100644 > index 000000000000..3c9bacd3c3f3 > --- /dev/null > +++ b/arch/x86/kernel/cc_platform.c > @@ -0,0 +1,21 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Confidential Computing Platform Capability checks > + * > + * Copyright (C) 2021 Advanced Micro Devices, Inc. > + * > + * Author: Tom Lendacky <thomas.lendacky@amd.com> > + */ > + > +#include <linux/export.h> > +#include <linux/cc_platform.h> > +#include <linux/mem_encrypt.h> > + > +bool cc_platform_has(enum cc_attr attr) > +{ > + if (sme_me_mask) Why are you still checking the sme_me_mask here? AFAIR, we said that we'll do that only when the KVM folks come with a valid use case... > + return amd_cc_platform_has(attr); > + > + return false; > +} > +EXPORT_SYMBOL_GPL(cc_platform_has); > diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c > index ff08dc463634..18fe19916bc3 100644 > --- a/arch/x86/mm/mem_encrypt.c > +++ b/arch/x86/mm/mem_encrypt.c > @@ -20,6 +20,7 @@ > #include <linux/bitops.h> > #include <linux/dma-mapping.h> > #include <linux/virtio_config.h> > +#include <linux/cc_platform.h> > > #include <asm/tlbflush.h> > #include <asm/fixmap.h> > @@ -389,6 +390,26 @@ bool noinstr sev_es_active(void) > return sev_status & MSR_AMD64_SEV_ES_ENABLED; > } > > +bool amd_cc_platform_has(enum cc_attr attr) > +{ > + switch (attr) { > + case CC_ATTR_MEM_ENCRYPT: > + return sme_me_mask != 0; No need for the "!= 0" -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 4e001bbbb425..2b2a9639d8ae 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1513,6 +1513,7 @@ config AMD_MEM_ENCRYPT select ARCH_HAS_FORCE_DMA_UNENCRYPTED select INSTRUCTION_DECODER select ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS + select ARCH_HAS_CC_PLATFORM 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/mem_encrypt.h b/arch/x86/include/asm/mem_encrypt.h index 9c80c68d75b5..3d8a5e8b2e3f 100644 --- a/arch/x86/include/asm/mem_encrypt.h +++ b/arch/x86/include/asm/mem_encrypt.h @@ -13,6 +13,7 @@ #ifndef __ASSEMBLY__ #include <linux/init.h> +#include <linux/cc_platform.h> #include <asm/bootparam.h> @@ -53,6 +54,7 @@ void __init sev_es_init_vc_handling(void); bool sme_active(void); bool sev_active(void); bool sev_es_active(void); +bool amd_cc_platform_has(enum cc_attr attr); #define __bss_decrypted __section(".bss..decrypted") @@ -78,6 +80,7 @@ static inline void sev_es_init_vc_handling(void) { } static inline bool sme_active(void) { return false; } static inline bool sev_active(void) { return false; } static inline bool sev_es_active(void) { return false; } +static inline bool amd_cc_platform_has(enum cc_attr attr) { return false; } static inline int __init early_set_memory_decrypted(unsigned long vaddr, unsigned long size) { return 0; } diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 8f4e8fa6ed75..f91403a78594 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -147,6 +147,9 @@ obj-$(CONFIG_UNWINDER_FRAME_POINTER) += unwind_frame.o obj-$(CONFIG_UNWINDER_GUESS) += unwind_guess.o obj-$(CONFIG_AMD_MEM_ENCRYPT) += sev.o + +obj-$(CONFIG_ARCH_HAS_CC_PLATFORM) += cc_platform.o + ### # 64 bit specific files ifeq ($(CONFIG_X86_64),y) diff --git a/arch/x86/kernel/cc_platform.c b/arch/x86/kernel/cc_platform.c new file mode 100644 index 000000000000..3c9bacd3c3f3 --- /dev/null +++ b/arch/x86/kernel/cc_platform.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Confidential Computing Platform Capability checks + * + * Copyright (C) 2021 Advanced Micro Devices, Inc. + * + * Author: Tom Lendacky <thomas.lendacky@amd.com> + */ + +#include <linux/export.h> +#include <linux/cc_platform.h> +#include <linux/mem_encrypt.h> + +bool cc_platform_has(enum cc_attr attr) +{ + if (sme_me_mask) + return amd_cc_platform_has(attr); + + return false; +} +EXPORT_SYMBOL_GPL(cc_platform_has); diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c index ff08dc463634..18fe19916bc3 100644 --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -20,6 +20,7 @@ #include <linux/bitops.h> #include <linux/dma-mapping.h> #include <linux/virtio_config.h> +#include <linux/cc_platform.h> #include <asm/tlbflush.h> #include <asm/fixmap.h> @@ -389,6 +390,26 @@ bool noinstr sev_es_active(void) return sev_status & MSR_AMD64_SEV_ES_ENABLED; } +bool amd_cc_platform_has(enum cc_attr attr) +{ + switch (attr) { + case CC_ATTR_MEM_ENCRYPT: + return sme_me_mask != 0; + + case CC_ATTR_HOST_MEM_ENCRYPT: + return sme_active(); + + case CC_ATTR_GUEST_MEM_ENCRYPT: + return sev_active(); + + case CC_ATTR_GUEST_STATE_ENCRYPT: + return sev_es_active(); + + default: + return false; + } +} + /* Override for DMA direct allocation check - ARCH_HAS_FORCE_DMA_UNENCRYPTED */ bool force_dma_unencrypted(struct device *dev) {