[PATCH 23/23] KVM: MMU: replace direct_map with mmu_role.direct

Paolo Bonzini
2022-02-04T11:58:40Z

direct_map is always equal to the role's direct field:

- for shadow paging, direct_map is true if CR0.PG=0 and mmu_role.direct is
copied from cpu_role.base.direct

- for TDP, it is always true and mmu_role.direct is also always true

- for shadow EPT, it is always false and mmu_role.direct is also always
false

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/include/asm/kvm_host.h | 1 -
arch/x86/kvm/mmu/mmu.c | 30 ++++++++++++++----------------
arch/x86/kvm/x86.c | 12 ++++++------
4 files changed, 21 insertions(+), 23 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index c86a2beee92a..647b3f6d02d0 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -432,7 +432,6 @@ struct kvm_mmu {
gpa_t root_pgd;
union kvm_mmu_role cpu_role;
union kvm_mmu_page_role mmu_role;
- bool direct_map;
struct kvm_mmu_root_info prev_roots[KVM_MMU_NUM_PREV_ROOTS];

/*
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 5a6541d6a424..ce55fad99671 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -2045,7 +2045,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
int direct,
unsigned int access)
{
- bool direct_mmu = vcpu->arch.mmu->direct_map;
+ bool direct_mmu = vcpu->arch.mmu->mmu_role.direct;
union kvm_mmu_page_role role;
struct hlist_head *sp_list;
unsigned quadrant;
@@ -2147,7 +2147,7 @@ static void shadow_walk_init_using_root(struct kvm_shadow_walk_iterator *iterato

if (iterator->level >= PT64_ROOT_4LEVEL &&
vcpu->arch.mmu->cpu_role.base.level < PT64_ROOT_4LEVEL &&
- !vcpu->arch.mmu->direct_map)
+ !vcpu->arch.mmu->mmu_role.direct)
iterator->level = PT32E_ROOT_LEVEL;

if (iterator->level == PT32E_ROOT_LEVEL) {
@@ -2523,7 +2523,7 @@ static int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva)
gpa_t gpa;
int r;

- if (vcpu->arch.mmu->direct_map)
+ if (vcpu->arch.mmu->mmu_role.direct)
return 0;

gpa = kvm_mmu_gva_to_gpa_read(vcpu, gva, NULL);
@@ -3255,7 +3255,8 @@ void kvm_mmu_free_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,

if (free_active_root) {
if (mmu->mmu_role.level >= PT64_ROOT_4LEVEL &&
- (mmu->cpu_role.base.level >= PT64_ROOT_4LEVEL || mmu->direct_map)) {
+ (mmu->cpu_role.base.level >= PT64_ROOT_4LEVEL ||
+ mmu->mmu_role.direct)) {
mmu_free_root_page(kvm, &mmu->root_hpa, &invalid_list);
} else if (mmu->pae_root) {
for (i = 0; i < 4; ++i) {
@@ -3558,7 +3559,8 @@ static int mmu_alloc_special_roots(struct kvm_vcpu *vcpu)
* equivalent level in the guest's NPT to shadow. Allocate the tables
* on demand, as running a 32-bit L1 VMM on 64-bit KVM is very rare.
*/
- if (mmu->direct_map || mmu->cpu_role.base.level >= PT64_ROOT_4LEVEL ||
+ if (mmu->mmu_role.direct ||
+ mmu->cpu_role.base.level >= PT64_ROOT_4LEVEL ||
mmu->mmu_role.level < PT64_ROOT_4LEVEL)
return 0;

@@ -3647,7 +3649,7 @@ void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu)
int i;
struct kvm_mmu_page *sp;

- if (vcpu->arch.mmu->direct_map)
+ if (vcpu->arch.mmu->mmu_role.direct)
return;

if (!VALID_PAGE(vcpu->arch.mmu->root_hpa))
@@ -3872,7 +3874,7 @@ static bool kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,

arch.token = (vcpu->arch.apf.id++ << 12) | vcpu->vcpu_id;
arch.gfn = gfn;
- arch.direct_map = vcpu->arch.mmu->direct_map;
+ arch.direct_map = vcpu->arch.mmu->mmu_role.direct;
arch.cr3 = vcpu->arch.mmu->get_guest_pgd(vcpu);

return kvm_setup_async_pf(vcpu, cr2_or_gpa,
@@ -4090,7 +4092,6 @@ static void nonpaging_init_context(struct kvm_mmu *context)
context->gva_to_gpa = nonpaging_gva_to_gpa;
context->sync_page = nonpaging_sync_page;
context->invlpg = NULL;
- context->direct_map = true;
}

static inline bool is_root_usable(struct kvm_mmu_root_info *root, gpa_t pgd,
@@ -4641,7 +4642,6 @@ static void paging64_init_context(struct kvm_mmu *context)
context->gva_to_gpa = paging64_gva_to_gpa;
context->sync_page = paging64_sync_page;
context->invlpg = paging64_invlpg;
- context->direct_map = false;
}

static void paging32_init_context(struct kvm_mmu *context)
@@ -4650,7 +4650,6 @@ static void paging32_init_context(struct kvm_mmu *context)
context->gva_to_gpa = paging32_gva_to_gpa;
context->sync_page = paging32_sync_page;
context->invlpg = paging32_invlpg;
- context->direct_map = false;
}

static union kvm_mmu_role
@@ -4735,7 +4734,6 @@ static void init_kvm_tdp_mmu(struct kvm_vcpu *vcpu, union kvm_mmu_role cpu_role)
context->page_fault = kvm_tdp_page_fault;
context->sync_page = nonpaging_sync_page;
context->invlpg = NULL;
- context->direct_map = true;
context->get_guest_pgd = get_cr3;
context->get_pdptr = kvm_pdptr_read;
context->inject_page_fault = kvm_inject_page_fault;
@@ -4852,7 +4850,7 @@ void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly,
context->gva_to_gpa = ept_gva_to_gpa;
context->sync_page = ept_sync_page;
context->invlpg = ept_invlpg;
- context->direct_map = false;
+
update_permission_bitmask(context, true);
context->pkru_mask = 0;
reset_rsvds_bits_mask_ept(vcpu, context, execonly, huge_page_level);
@@ -4967,13 +4965,13 @@ int kvm_mmu_load(struct kvm_vcpu *vcpu)
{
int r;

- r = mmu_topup_memory_caches(vcpu, !vcpu->arch.mmu->direct_map);
+ r = mmu_topup_memory_caches(vcpu, !vcpu->arch.mmu->mmu_role.direct);
if (r)
goto out;
r = mmu_alloc_special_roots(vcpu);
if (r)
goto out;
- if (vcpu->arch.mmu->direct_map)
+ if (vcpu->arch.mmu->mmu_role.direct)
r = mmu_alloc_direct_roots(vcpu);
else
r = mmu_alloc_shadow_roots(vcpu);
@@ -5176,7 +5174,7 @@ int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 error_code,
void *insn, int insn_len)
{
int r, emulation_type = EMULTYPE_PF;
- bool direct = vcpu->arch.mmu->direct_map;
+ bool direct = vcpu->arch.mmu->mmu_role.direct;

if (WARN_ON(!VALID_PAGE(vcpu->arch.mmu->root_hpa)))
return RET_PF_RETRY;
@@ -5207,7 +5205,7 @@ int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 error_code,
* paging in both guests. If true, we simply unprotect the page
* and resume the guest.
*/
- if (vcpu->arch.mmu->direct_map &&
+ if (vcpu->arch.mmu->mmu_role.direct &&
(error_code & PFERR_NESTED_GUEST_PAGE) == PFERR_NESTED_GUEST_PAGE) {
kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(cr2_or_gpa));
return 1;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 657aa646871e..b910fa34e57e 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7978,7 +7978,7 @@ static bool reexecute_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
WARN_ON_ONCE(!(emulation_type & EMULTYPE_PF)))
return false;

- if (!vcpu->arch.mmu->direct_map) {
+ if (!vcpu->arch.mmu->mmu_role.direct) {
/*
* Write permission should be allowed since only
* write access need to be emulated.
@@ -8011,7 +8011,7 @@ static bool reexecute_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
kvm_release_pfn_clean(pfn);

/* The instructions are well-emulated on direct mmu. */
- if (vcpu->arch.mmu->direct_map) {
+ if (vcpu->arch.mmu->mmu_role.direct) {
unsigned int indirect_shadow_pages;

write_lock(&vcpu->kvm->mmu_lock);
@@ -8079,7 +8079,7 @@ static bool retry_instruction(struct x86_emulate_ctxt *ctxt,
vcpu->arch.last_retry_eip = ctxt->eip;
vcpu->arch.last_retry_addr = cr2_or_gpa;

- if (!vcpu->arch.mmu->direct_map)
+ if (!vcpu->arch.mmu->mmu_role.direct)
gpa = kvm_mmu_gva_to_gpa_write(vcpu, cr2_or_gpa, NULL);

kvm_mmu_unprotect_page(vcpu->kvm, gpa_to_gfn(gpa));
@@ -8359,7 +8359,7 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
ctxt->exception.address = cr2_or_gpa;

/* With shadow page tables, cr2 contains a GVA or nGPA. */
- if (vcpu->arch.mmu->direct_map) {
+ if (vcpu->arch.mmu->mmu_role.direct) {
ctxt->gpa_available = true;
ctxt->gpa_val = cr2_or_gpa;
}
@@ -12196,7 +12196,7 @@ void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu, struct kvm_async_pf *work)
{
int r;

- if ((vcpu->arch.mmu->direct_map != work->arch.direct_map) ||
+ if ((vcpu->arch.mmu->mmu_role.direct != work->arch.direct_map) ||
work->wakeup_all)
return;

@@ -12204,7 +12204,7 @@ void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu, struct kvm_async_pf *work)
if (unlikely(r))
return;

- if (!vcpu->arch.mmu->direct_map &&
+ if (!vcpu->arch.mmu->mmu_role.direct &&
work->arch.cr3 != vcpu->arch.mmu->get_guest_pgd(vcpu))
return;

--
2.31.1