diff options
author | Paolo Bonzini <pbonzini@redhat.com> | 2021-11-11 15:40:26 +0300 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-11-11 15:40:26 +0300 |
commit | b9ecb9a997333f90236cb6f3d52d83987a17addc (patch) | |
tree | 9d4c34b26ba67337923c8681daf32d1b162426c8 /arch/x86/mm/mem_encrypt.c | |
parent | debe436e77c72fcee804fb867f275e6d31aa999c (diff) | |
parent | 73f1b4fece216c2e72be74c4d0d0f71a0b944bec (diff) | |
download | linux-b9ecb9a997333f90236cb6f3d52d83987a17addc.tar.xz |
Merge branch 'kvm-guest-sev-migration' into kvm-master
Add guest api and guest kernel support for SEV live migration.
Introduces a new hypercall to notify the host of changes to the page
encryption status. If the page is encrypted then it must be migrated
through the SEV firmware or a helper VM sharing the key. If page is
not encrypted then it can be migrated normally by userspace. This new
hypercall is invoked using paravirt_ops.
Conflicts: sev_active() replaced by cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT).
Diffstat (limited to 'arch/x86/mm/mem_encrypt.c')
-rw-r--r-- | arch/x86/mm/mem_encrypt.c | 72 |
1 files changed, 63 insertions, 9 deletions
diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c index 23d54b810f08..35487305d8af 100644 --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -229,28 +229,75 @@ void __init sev_setup_arch(void) swiotlb_adjust_size(size); } -static void __init __set_clr_pte_enc(pte_t *kpte, int level, bool enc) +static unsigned long pg_level_to_pfn(int level, pte_t *kpte, pgprot_t *ret_prot) { - pgprot_t old_prot, new_prot; - unsigned long pfn, pa, size; - pte_t new_pte; + unsigned long pfn = 0; + pgprot_t prot; switch (level) { case PG_LEVEL_4K: pfn = pte_pfn(*kpte); - old_prot = pte_pgprot(*kpte); + prot = pte_pgprot(*kpte); break; case PG_LEVEL_2M: pfn = pmd_pfn(*(pmd_t *)kpte); - old_prot = pmd_pgprot(*(pmd_t *)kpte); + prot = pmd_pgprot(*(pmd_t *)kpte); break; case PG_LEVEL_1G: pfn = pud_pfn(*(pud_t *)kpte); - old_prot = pud_pgprot(*(pud_t *)kpte); + prot = pud_pgprot(*(pud_t *)kpte); break; default: - return; + WARN_ONCE(1, "Invalid level for kpte\n"); + return 0; + } + + if (ret_prot) + *ret_prot = prot; + + return pfn; +} + +void notify_range_enc_status_changed(unsigned long vaddr, int npages, bool enc) +{ +#ifdef CONFIG_PARAVIRT + unsigned long sz = npages << PAGE_SHIFT; + unsigned long vaddr_end = vaddr + sz; + + while (vaddr < vaddr_end) { + int psize, pmask, level; + unsigned long pfn; + pte_t *kpte; + + kpte = lookup_address(vaddr, &level); + if (!kpte || pte_none(*kpte)) { + WARN_ONCE(1, "kpte lookup for vaddr\n"); + return; + } + + pfn = pg_level_to_pfn(level, kpte, NULL); + if (!pfn) + continue; + + psize = page_level_size(level); + pmask = page_level_mask(level); + + notify_page_enc_status_changed(pfn, psize >> PAGE_SHIFT, enc); + + vaddr = (vaddr & pmask) + psize; } +#endif +} + +static void __init __set_clr_pte_enc(pte_t *kpte, int level, bool enc) +{ + pgprot_t old_prot, new_prot; + unsigned long pfn, pa, size; + pte_t new_pte; + + pfn = pg_level_to_pfn(level, kpte, &old_prot); + if (!pfn) + return; new_prot = old_prot; if (enc) @@ -286,12 +333,13 @@ static void __init __set_clr_pte_enc(pte_t *kpte, int level, bool enc) static int __init early_set_memory_enc_dec(unsigned long vaddr, unsigned long size, bool enc) { - unsigned long vaddr_end, vaddr_next; + unsigned long vaddr_end, vaddr_next, start; unsigned long psize, pmask; int split_page_size_mask; int level, ret; pte_t *kpte; + start = vaddr; vaddr_next = vaddr; vaddr_end = vaddr + size; @@ -346,6 +394,7 @@ static int __init early_set_memory_enc_dec(unsigned long vaddr, ret = 0; + notify_range_enc_status_changed(start, PAGE_ALIGN(size) >> PAGE_SHIFT, enc); out: __flush_tlb_all(); return ret; @@ -361,6 +410,11 @@ int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size) return early_set_memory_enc_dec(vaddr, size, true); } +void __init early_set_mem_enc_dec_hypercall(unsigned long vaddr, int npages, bool enc) +{ + notify_range_enc_status_changed(vaddr, npages, enc); +} + /* Override for DMA direct allocation check - ARCH_HAS_FORCE_DMA_UNENCRYPTED */ bool force_dma_unencrypted(struct device *dev) { |