From: Yulei Zhang <yuleixzh...@tencent.com>
Construct the direct build ept when guest memory slots have been
changed, and issue mmu_reload request to update the CR3 so that
guest could use the pre-constructed EPT without page fault.
Signed-off-by: Yulei Zhang <yuleixzh...@tencent.com>
---
arch/mips/kvm/mips.c | 13 +++++++++++++
arch/powerpc/kvm/powerpc.c | 13 +++++++++++++
arch/s390/kvm/kvm-s390.c | 13 +++++++++++++
arch/x86/kvm/mmu/mmu.c | 33 ++++++++++++++++++++++++++-------
include/linux/kvm_host.h | 3 +++
virt/kvm/kvm_main.c | 13 +++++++++++++
6 files changed, 81 insertions(+), 7 deletions(-)
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index 8f05dd0a0f4e..7e5608769696 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -257,6 +257,19 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
}
}
+int kvm_direct_tdp_populate_page_table(struct kvm *kvm, struct kvm_memory_slot
*slot)
+{
+ return 0;
+}
+
+void kvm_direct_tdp_remove_page_table(struct kvm *kvm, struct kvm_memory_slot
*slot)
+{
+}
+
+void kvm_direct_tdp_release_global_root(struct kvm *kvm)
+{
+}
+
static inline void dump_handler(const char *symbol, void *start, void *end)
{
u32 *p;
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index ad2f172c26a6..93066393e09d 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -712,6 +712,19 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
kvmppc_core_commit_memory_region(kvm, mem, old, new, change);
}
+int kvm_direct_tdp_populate_page_table(struct kvm *kvm, struct kvm_memory_slot
*slot)
+{
+ return 0;
+}
+
+void kvm_direct_tdp_remove_page_table(struct kvm *kvm, struct kvm_memory_slot
*slot)
+{
+}
+
+void kvm_direct_tdp_release_global_root(struct kvm *kvm)
+{
+}
+
void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
struct kvm_memory_slot *slot)
{
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index d05bb040fd42..594c38a7cc9f 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -5008,6 +5008,19 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
return;
}
+int kvm_direct_tdp_populate_page_table(struct kvm *kvm, struct kvm_memory_slot
*slot)
+{
+ return 0;
+}
+
+void kvm_direct_tdp_remove_page_table(struct kvm *kvm, struct kvm_memory_slot
*slot)
+{
+}
+
+void kvm_direct_tdp_release_global_root(struct kvm *kvm)
+{
+}
+
static inline unsigned long nonhyp_mask(int i)
{
unsigned int nonhyp_fai = (sclp.hmfai << i * 2) >> 30;
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index b59a4502d1f6..33252e432c1b 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -5203,13 +5203,20 @@ int kvm_mmu_load(struct kvm_vcpu *vcpu)
{
int r;
- r = mmu_topup_memory_caches(vcpu);
- if (r)
- goto out;
- r = mmu_alloc_roots(vcpu);
- kvm_mmu_sync_roots(vcpu);
- if (r)
- goto out;
+ if (vcpu->kvm->arch.global_root_hpa) {
+ vcpu->arch.direct_build_tdp = true;
+ vcpu->arch.mmu->root_hpa = vcpu->kvm->arch.global_root_hpa;
+ }
+
+ if (!vcpu->arch.direct_build_tdp) {
+ r = mmu_topup_memory_caches(vcpu);
+ if (r)
+ goto out;
+ r = mmu_alloc_roots(vcpu);
+ kvm_mmu_sync_roots(vcpu);
+ if (r)
+ goto out;
+ }
kvm_mmu_load_pgd(vcpu);
kvm_x86_ops.tlb_flush(vcpu, true);
out:
@@ -6438,6 +6445,17 @@ int direct_build_mapping_level(struct kvm *kvm, struct
kvm_memory_slot *slot, gf
return host_level;
}
+static void kvm_make_direct_build_update(struct kvm *kvm)
+{
+ int i;
+ struct kvm_vcpu *vcpu;
+
+ kvm_for_each_vcpu(i, vcpu, kvm) {
+ kvm_make_request(KVM_REQ_MMU_RELOAD, vcpu);
+ kvm_vcpu_kick(vcpu);
+ }
+}
+
int kvm_direct_tdp_populate_page_table(struct kvm *kvm, struct kvm_memory_slot
*slot)
{
gfn_t gfn;
@@ -6472,6 +6490,7 @@ int kvm_direct_tdp_populate_page_table(struct kvm *kvm,
struct kvm_memory_slot *
direct_build_tdp_map(kvm, slot, gfn, pfn, host_level);
}
+ kvm_make_direct_build_update(kvm);
return 0;
}
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index d1f75ad5038b..767e5c4ed295 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -693,6 +693,9 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
struct kvm_memory_slot *old,
const struct kvm_memory_slot *new,
enum kvm_mr_change change);
+int kvm_direct_tdp_populate_page_table(struct kvm *kvm, struct kvm_memory_slot
*slot);
+void kvm_direct_tdp_remove_page_table(struct kvm *kvm, struct kvm_memory_slot
*slot);
+void kvm_direct_tdp_release_global_root(struct kvm *kvm);
void mark_page_dirty_in_slot(struct kvm_memory_slot *memslot, gfn_t gfn);
/* flush all memory translations */
void kvm_arch_flush_shadow_all(struct kvm *kvm);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 46217b1c8353..eb0f6ad2f369 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -820,6 +820,7 @@ static void kvm_destroy_vm(struct kvm *kvm)
#endif
kvm_arch_destroy_vm(kvm);
kvm_destroy_devices(kvm);
+ kvm_direct_tdp_release_global_root(kvm);
for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
kvm_free_memslots(kvm, __kvm_memslots(kvm, i));
cleanup_srcu_struct(&kvm->irq_srcu);
@@ -1139,6 +1140,10 @@ static int kvm_set_memslot(struct kvm *kvm,
* in the freshly allocated memslots, not in @old or @new.
*/
slot = id_to_memslot(slots, old->id);
+ /* Remove pre-constructed page table */
+ if (!as_id)
+ kvm_direct_tdp_remove_page_table(kvm, slot);
+
slot->flags |= KVM_MEMSLOT_INVALID;
/*
@@ -1166,6 +1171,14 @@ static int kvm_set_memslot(struct kvm *kvm,
update_memslots(slots, new, change);
slots = install_new_memslots(kvm, as_id, slots);
+ if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
+ if (!as_id) {
+ r = kvm_direct_tdp_populate_page_table(kvm, new);
+ if (r)
+ goto out_slots;
+ }
+ }
+
kvm_arch_commit_memory_region(kvm, mem, old, new, change);
kvfree(slots);
--
2.17.1
