From: Izik Eidus Date: Wed, 23 Sep 2009 18:47:18 +0000 (+0300) Subject: KVM: add support for change_pte mmu notifiers X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=3da0dd433dc399a8c0124d0614d82a09b6a49bce;p=linux-beck.git KVM: add support for change_pte mmu notifiers this is needed for kvm if it want ksm to directly map pages into its shadow page tables. [marcelo: cast pfn assignment to u64] Signed-off-by: Izik Eidus Signed-off-by: Marcelo Tosatti --- diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 3be000435fad..d83892226f73 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -796,6 +796,7 @@ asmlinkage void kvm_handle_fault_on_reboot(void); #define KVM_ARCH_WANT_MMU_NOTIFIER int kvm_unmap_hva(struct kvm *kvm, unsigned long hva); int kvm_age_hva(struct kvm *kvm, unsigned long hva); +void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte); int cpuid_maxphyaddr(struct kvm_vcpu *vcpu); int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu); int kvm_arch_interrupt_allowed(struct kvm_vcpu *vcpu); diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 5cd8b4ec3a01..685a4ffac8e6 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -748,7 +748,7 @@ static int rmap_write_protect(struct kvm *kvm, u64 gfn) return write_protected; } -static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp) +static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp, u64 data) { u64 *spte; int need_tlb_flush = 0; @@ -763,8 +763,45 @@ static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp) return need_tlb_flush; } -static int kvm_handle_hva(struct kvm *kvm, unsigned long hva, - int (*handler)(struct kvm *kvm, unsigned long *rmapp)) +static int kvm_set_pte_rmapp(struct kvm *kvm, unsigned long *rmapp, u64 data) +{ + int need_flush = 0; + u64 *spte, new_spte; + pte_t *ptep = (pte_t *)data; + pfn_t new_pfn; + + WARN_ON(pte_huge(*ptep)); + new_pfn = pte_pfn(*ptep); + spte = rmap_next(kvm, rmapp, NULL); + while (spte) { + BUG_ON(!is_shadow_present_pte(*spte)); + rmap_printk("kvm_set_pte_rmapp: spte %p %llx\n", spte, *spte); + need_flush = 1; + if (pte_write(*ptep)) { + rmap_remove(kvm, spte); + __set_spte(spte, shadow_trap_nonpresent_pte); + spte = rmap_next(kvm, rmapp, NULL); + } else { + new_spte = *spte &~ (PT64_BASE_ADDR_MASK); + new_spte |= (u64)new_pfn << PAGE_SHIFT; + + new_spte &= ~PT_WRITABLE_MASK; + new_spte &= ~SPTE_HOST_WRITEABLE; + if (is_writeble_pte(*spte)) + kvm_set_pfn_dirty(spte_to_pfn(*spte)); + __set_spte(spte, new_spte); + spte = rmap_next(kvm, rmapp, spte); + } + } + if (need_flush) + kvm_flush_remote_tlbs(kvm); + + return 0; +} + +static int kvm_handle_hva(struct kvm *kvm, unsigned long hva, u64 data, + int (*handler)(struct kvm *kvm, unsigned long *rmapp, + u64 data)) { int i, j; int retval = 0; @@ -786,13 +823,15 @@ static int kvm_handle_hva(struct kvm *kvm, unsigned long hva, if (hva >= start && hva < end) { gfn_t gfn_offset = (hva - start) >> PAGE_SHIFT; - retval |= handler(kvm, &memslot->rmap[gfn_offset]); + retval |= handler(kvm, &memslot->rmap[gfn_offset], + data); for (j = 0; j < KVM_NR_PAGE_SIZES - 1; ++j) { int idx = gfn_offset; idx /= KVM_PAGES_PER_HPAGE(PT_DIRECTORY_LEVEL + j); retval |= handler(kvm, - &memslot->lpage_info[j][idx].rmap_pde); + &memslot->lpage_info[j][idx].rmap_pde, + data); } } } @@ -802,10 +841,15 @@ static int kvm_handle_hva(struct kvm *kvm, unsigned long hva, int kvm_unmap_hva(struct kvm *kvm, unsigned long hva) { - return kvm_handle_hva(kvm, hva, kvm_unmap_rmapp); + return kvm_handle_hva(kvm, hva, 0, kvm_unmap_rmapp); +} + +void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte) +{ + kvm_handle_hva(kvm, hva, (u64)&pte, kvm_set_pte_rmapp); } -static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp) +static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp, u64 data) { u64 *spte; int young = 0; @@ -841,13 +885,13 @@ static void rmap_recycle(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn) gfn = unalias_gfn(vcpu->kvm, gfn); rmapp = gfn_to_rmap(vcpu->kvm, gfn, sp->role.level); - kvm_unmap_rmapp(vcpu->kvm, rmapp); + kvm_unmap_rmapp(vcpu->kvm, rmapp, 0); kvm_flush_remote_tlbs(vcpu->kvm); } int kvm_age_hva(struct kvm *kvm, unsigned long hva) { - return kvm_handle_hva(kvm, hva, kvm_age_rmapp); + return kvm_handle_hva(kvm, hva, 0, kvm_age_rmapp); } #ifdef MMU_DEBUG diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index e79c54034bcd..b7c78a403dc2 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -850,6 +850,19 @@ static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn, } +static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn, + struct mm_struct *mm, + unsigned long address, + pte_t pte) +{ + struct kvm *kvm = mmu_notifier_to_kvm(mn); + + spin_lock(&kvm->mmu_lock); + kvm->mmu_notifier_seq++; + kvm_set_spte_hva(kvm, address, pte); + spin_unlock(&kvm->mmu_lock); +} + static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, struct mm_struct *mm, unsigned long start, @@ -929,6 +942,7 @@ static const struct mmu_notifier_ops kvm_mmu_notifier_ops = { .invalidate_range_start = kvm_mmu_notifier_invalidate_range_start, .invalidate_range_end = kvm_mmu_notifier_invalidate_range_end, .clear_flush_young = kvm_mmu_notifier_clear_flush_young, + .change_pte = kvm_mmu_notifier_change_pte, .release = kvm_mmu_notifier_release, }; #endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */