From b577f542f93cbba57f8d6185ef1fb13a41ddf162 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Tue, 22 Feb 2022 21:57:40 +0300 Subject: x86/coco: Add API to handle encryption mask AMD SME/SEV uses a bit in the page table entries to indicate that the page is encrypted and not accessible to the VMM. TDX uses a similar approach, but the polarity of the mask is opposite to AMD: if the bit is set the page is accessible to VMM. Provide vendor-neutral API to deal with the mask: cc_mkenc() and cc_mkdec() modify given address to make it encrypted/decrypted. It can be applied to phys_addr_t, pgprotval_t or page table entry value. pgprot_encrypted() and pgprot_decrypted() reimplemented using new helpers. The implementation will be extended to cover TDX. pgprot_decrypted() is used by drivers (i915, virtio_gpu, vfio). cc_mkdec() called by pgprot_decrypted(). Export cc_mkdec(). Signed-off-by: Kirill A. Shutemov Signed-off-by: Borislav Petkov Reviewed-by: Tom Lendacky Link: https://lore.kernel.org/r/20220222185740.26228-5-kirill.shutemov@linux.intel.com --- arch/x86/mm/mem_encrypt_identity.c | 1 + arch/x86/mm/pat/set_memory.c | 5 +++-- 2 files changed, 4 insertions(+), 2 deletions(-) (limited to 'arch/x86/mm') diff --git a/arch/x86/mm/mem_encrypt_identity.c b/arch/x86/mm/mem_encrypt_identity.c index 06314ae3998e..b43bc24d2bb6 100644 --- a/arch/x86/mm/mem_encrypt_identity.c +++ b/arch/x86/mm/mem_encrypt_identity.c @@ -604,5 +604,6 @@ out: if (sme_me_mask) { physical_mask &= ~sme_me_mask; cc_set_vendor(CC_VENDOR_AMD); + cc_set_mask(sme_me_mask); } } diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c index b4072115c8ef..1441db69cea5 100644 --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -1989,6 +1989,7 @@ int set_memory_global(unsigned long addr, int numpages) */ static int __set_memory_enc_pgtable(unsigned long addr, int numpages, bool enc) { + pgprot_t empty = __pgprot(0); struct cpa_data cpa; int ret; @@ -1999,8 +2000,8 @@ static int __set_memory_enc_pgtable(unsigned long addr, int numpages, bool enc) memset(&cpa, 0, sizeof(cpa)); cpa.vaddr = &addr; cpa.numpages = numpages; - cpa.mask_set = enc ? __pgprot(_PAGE_ENC) : __pgprot(0); - cpa.mask_clr = enc ? __pgprot(0) : __pgprot(_PAGE_ENC); + cpa.mask_set = enc ? pgprot_encrypted(empty) : pgprot_decrypted(empty); + cpa.mask_clr = enc ? pgprot_decrypted(empty) : pgprot_encrypted(empty); cpa.pgd = init_mm.pgd; /* Must avoid aliasing mappings in the highmem code */ -- cgit v1.2.3