When KVM updates accessed/dirty bits, this hook can be used to invoke an arch specific function that implements/emulates dirty logging such as PML.
Signed-off-by: Bandan Das <[email protected]> --- arch/x86/include/asm/kvm_host.h | 2 ++ arch/x86/kvm/mmu.c | 15 +++++++++++++++ arch/x86/kvm/mmu.h | 1 + arch/x86/kvm/paging_tmpl.h | 4 ++++ 4 files changed, 22 insertions(+) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index f5bddf92..9c761fe 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1020,6 +1020,8 @@ struct kvm_x86_ops { void (*enable_log_dirty_pt_masked)(struct kvm *kvm, struct kvm_memory_slot *slot, gfn_t offset, unsigned long mask); + int (*write_log_dirty)(struct kvm_vcpu *vcpu); + /* pmu operations of sub-arch */ const struct kvm_pmu_ops *pmu_ops; diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 5586765..5d3376f 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1498,6 +1498,21 @@ void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm, kvm_mmu_write_protect_pt_masked(kvm, slot, gfn_offset, mask); } +/** + * kvm_arch_write_log_dirty - emulate dirty page logging + * @vcpu: Guest mode vcpu + * + * Emulate arch specific page modification logging for the + * nested hypervisor + */ +int kvm_arch_write_log_dirty(struct kvm_vcpu *vcpu) +{ + if (kvm_x86_ops->write_log_dirty) + return kvm_x86_ops->write_log_dirty(vcpu); + + return 0; +} + bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm, struct kvm_memory_slot *slot, u64 gfn) { diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h index d8ccb32..2797580 100644 --- a/arch/x86/kvm/mmu.h +++ b/arch/x86/kvm/mmu.h @@ -202,4 +202,5 @@ void kvm_mmu_gfn_disallow_lpage(struct kvm_memory_slot *slot, gfn_t gfn); void kvm_mmu_gfn_allow_lpage(struct kvm_memory_slot *slot, gfn_t gfn); bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm, struct kvm_memory_slot *slot, u64 gfn); +int kvm_arch_write_log_dirty(struct kvm_vcpu *vcpu); #endif diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index 314d207..5624174 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -226,6 +226,10 @@ static int FNAME(update_accessed_dirty_bits)(struct kvm_vcpu *vcpu, if (level == walker->level && write_fault && !(pte & PT_GUEST_DIRTY_MASK)) { trace_kvm_mmu_set_dirty_bit(table_gfn, index, sizeof(pte)); +#if PTTYPE == PTTYPE_EPT + if (kvm_arch_write_log_dirty(vcpu)) + return -EINVAL; +#endif pte |= PT_GUEST_DIRTY_MASK; } if (pte == orig_pte) -- 2.9.3
