[PATCH v2 12/15] KVM: x86/tdp_mmu: Take root types for kvm_tdp_mmu_invalidate_all_roots()

From: Rick Edgecombe
Date: Thu May 30 2024 - 17:11:03 EST


From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>

Rename kvm_tdp_mmu_invalidate_all_roots() to
kvm_tdp_mmu_invalidate_roots(), and make it enum kvm_tdp_mmu_root_types
as an argument.

Have the callers only invalidate the required roots instead of all
roots.

Suggested-by: Chao Gao <chao.gao@xxxxxxxxx>
Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
---
TDX MMU Prep v2:
- Use process enum instead of root

TDX MMU Prep:
- New patch
---
arch/x86/kvm/mmu/mmu.c | 9 +++++++--
arch/x86/kvm/mmu/tdp_mmu.c | 5 +++--
arch/x86/kvm/mmu/tdp_mmu.h | 3 ++-
3 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 01fb918612ae..0b173aa08728 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -6414,8 +6414,13 @@ static void kvm_mmu_zap_all_fast(struct kvm *kvm)
* write and in the same critical section as making the reload request,
* e.g. before kvm_zap_obsolete_pages() could drop mmu_lock and yield.
*/
- if (tdp_mmu_enabled)
- kvm_tdp_mmu_invalidate_all_roots(kvm);
+ if (tdp_mmu_enabled) {
+ /*
+ * The private page tables doesn't support fast zapping. The
+ * caller should handle it by other way.
+ */
+ kvm_tdp_mmu_invalidate_roots(kvm, KVM_PROCESS_SHARED);
+ }

/*
* Notify all vcpus to reload its shadow page table and flush TLB.
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 1245f6a48dbe..4f00ae7da072 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -37,7 +37,7 @@ void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm)
* for zapping and thus puts the TDP MMU's reference to each root, i.e.
* ultimately frees all roots.
*/
- kvm_tdp_mmu_invalidate_all_roots(kvm);
+ kvm_tdp_mmu_invalidate_roots(kvm, KVM_PROCESS_PRIVATE_AND_SHARED);
kvm_tdp_mmu_zap_invalidated_roots(kvm);

WARN_ON(atomic64_read(&kvm->arch.tdp_mmu_pages));
@@ -1132,7 +1132,8 @@ void kvm_tdp_mmu_zap_invalidated_roots(struct kvm *kvm)
* Note, kvm_tdp_mmu_zap_invalidated_roots() is gifted the TDP MMU's reference.
* See kvm_tdp_mmu_alloc_root().
*/
-void kvm_tdp_mmu_invalidate_all_roots(struct kvm *kvm)
+void kvm_tdp_mmu_invalidate_roots(struct kvm *kvm,
+ enum kvm_process process_types)
{
struct kvm_mmu_page *root;

diff --git a/arch/x86/kvm/mmu/tdp_mmu.h b/arch/x86/kvm/mmu/tdp_mmu.h
index 934269b82f20..30b1288c1e4d 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.h
+++ b/arch/x86/kvm/mmu/tdp_mmu.h
@@ -62,7 +62,8 @@ static inline struct kvm_mmu_page *tdp_mmu_get_root(struct kvm_vcpu *vcpu, enum
bool kvm_tdp_mmu_zap_leafs(struct kvm *kvm, gfn_t start, gfn_t end, bool flush);
bool kvm_tdp_mmu_zap_sp(struct kvm *kvm, struct kvm_mmu_page *sp);
void kvm_tdp_mmu_zap_all(struct kvm *kvm);
-void kvm_tdp_mmu_invalidate_all_roots(struct kvm *kvm);
+void kvm_tdp_mmu_invalidate_roots(struct kvm *kvm,
+ enum kvm_process types);
void kvm_tdp_mmu_zap_invalidated_roots(struct kvm *kvm);

int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault);
--
2.34.1