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Cc: James Houghton Signed-off-by: Sean Christopherson --- arch/x86/kvm/mmu/mmu.c | 63 +++++++++++++++++++++++++++++++++++++++--- 1 file changed, 59 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 48e8608c2738..9df6b465de06 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -995,13 +995,11 @@ static void kvm_rmap_unlock(struct kvm_rmap_head *rma= p_head, * locking is the same, but the caller is disallowed from modifying the rm= ap, * and so the unlock flow is a nop if the rmap is/was empty. */ -__maybe_unused static unsigned long kvm_rmap_lock_readonly(struct kvm_rmap_head *rmap_hea= d) { return __kvm_rmap_lock(rmap_head); } =20 -__maybe_unused static void kvm_rmap_unlock_readonly(struct kvm_rmap_head *rmap_head, unsigned long old_val) { @@ -1743,8 +1741,53 @@ static void rmap_add(struct kvm_vcpu *vcpu, const st= ruct kvm_memory_slot *slot, __rmap_add(vcpu->kvm, cache, slot, spte, gfn, access); } =20 -static bool kvm_rmap_age_gfn_range(struct kvm *kvm, - struct kvm_gfn_range *range, bool test_only) +static bool kvm_rmap_age_gfn_range_lockless(struct kvm *kvm, + struct kvm_gfn_range *range, + bool test_only) +{ + struct kvm_rmap_head *rmap_head; + struct rmap_iterator iter; + unsigned long rmap_val; + bool young =3D false; + u64 *sptep; + gfn_t gfn; + int level; + u64 spte; + + for (level =3D PG_LEVEL_4K; level <=3D KVM_MAX_HUGEPAGE_LEVEL; level++) { + for (gfn =3D range->start; gfn < range->end; + gfn +=3D KVM_PAGES_PER_HPAGE(level)) { + rmap_head =3D gfn_to_rmap(gfn, level, range->slot); + rmap_val =3D kvm_rmap_lock_readonly(rmap_head); + + for_each_rmap_spte_lockless(rmap_head, &iter, sptep, spte) { + if (!is_accessed_spte(spte)) + continue; + + if (test_only) { + kvm_rmap_unlock_readonly(rmap_head, rmap_val); + return true; + } + + /* + * Marking SPTEs for access tracking outside of + * mmu_lock is unsupported. Report the page as + * young, but otherwise leave it as-is. + */ + if (spte_ad_enabled(spte)) + clear_bit((ffs(shadow_accessed_mask) - 1), + (unsigned long *)sptep); + young =3D true; + } + + kvm_rmap_unlock_readonly(rmap_head, rmap_val); + } + } + return young; +} + +static bool __kvm_rmap_age_gfn_range(struct kvm *kvm, + struct kvm_gfn_range *range, bool test_only) { struct slot_rmap_walk_iterator iterator; struct rmap_iterator iter; @@ -1783,6 +1826,18 @@ static bool kvm_rmap_age_gfn_range(struct kvm *kvm, return young; } =20 + +static bool kvm_rmap_age_gfn_range(struct kvm *kvm, + struct kvm_gfn_range *range, bool test_only) +{ + /* FIXME: This also needs to be guarded with something like range->fast_o= nly. */ + if (kvm_ad_enabled()) + return kvm_rmap_age_gfn_range_lockless(kvm, range, test_only); + + lockdep_assert_held_write(&kvm->mmu_lock); + return __kvm_rmap_age_gfn_range(kvm, range, test_only); +} + bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) { bool young =3D false; --=20 2.46.0.76.ge559c4bf1a-goog