KVM: X86: Change the type of access u32 to u64

Change the type of access u32 to u64 for FNAME(walk_addr) and
->gva_to_gpa().

The kinds of accesses are usually combinations of UWX, and VMX/SVM's
nested paging adds a new factor of access: is it an access for a guest
page table or for a final guest physical address.

And SMAP relies a factor for supervisor access: explicit or implicit.

So @access in FNAME(walk_addr) and ->gva_to_gpa() is better to include
all these information to do the walk.

Although @access(u32) has enough bits to encode all the kinds, this
patch extends it to u64:
	o Extra bits will be in the higher 32 bits, so that we can
	  easily obtain the traditional access mode (UWX) by converting
	  it to u32.
	o Reuse the value for the access kind defined by SVM's nested
	  paging (PFERR_GUEST_FINAL_MASK and PFERR_GUEST_PAGE_MASK) as
	  @error_code in kvm_handle_page_fault().

Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Message-Id: <20220311070346.45023-2-jiangshanlai@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

5 files changed, 23 insertions, 21 deletions

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 47de0226d674..71cfc9fdf946 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -430,7 +430,7 @@ struct kvm_mmu {
 	void (*inject_page_fault)(struct kvm_vcpu *vcpu,
 				  struct x86_exception *fault);
 	gpa_t (*gva_to_gpa)(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
-			    gpa_t gva_or_gpa, u32 access,
+			    gpa_t gva_or_gpa, u64 access,
 			    struct x86_exception *exception);
 	int (*sync_page)(struct kvm_vcpu *vcpu,
 			 struct kvm_mmu_page *sp);
diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index bf8dbc4bb12a..74efeaefa8f8 100644
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -214,8 +214,10 @@ static inline int kvm_mmu_do_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
  */
 static inline u8 permission_fault(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
 				  unsigned pte_access, unsigned pte_pkey,
-				  unsigned pfec)
+				  u64 access)
 {
+	/* strip nested paging fault error codes */
+	unsigned int pfec = access;
 	int cpl = static_call(kvm_x86_get_cpl)(vcpu);
 	unsigned long rflags = static_call(kvm_x86_get_rflags)(vcpu);
 
@@ -317,12 +319,12 @@ static inline void kvm_update_page_stats(struct kvm *kvm, int level, int count)
 	atomic64_add(count, &kvm->stat.pages[level - 1]);
 }
 
-gpa_t translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u32 access,
+gpa_t translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u64 access,
 			   struct x86_exception *exception);
 
 static inline gpa_t kvm_translate_gpa(struct kvm_vcpu *vcpu,
 				      struct kvm_mmu *mmu,
-				      gpa_t gpa, u32 access,
+				      gpa_t gpa, u64 access,
 				      struct x86_exception *exception)
 {
 	if (mmu != &vcpu->arch.nested_mmu)
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 333aaf6d6806..7efa916f93ce 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3703,7 +3703,7 @@ void kvm_mmu_sync_prev_roots(struct kvm_vcpu *vcpu)
 }
 
 static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
-				  gpa_t vaddr, u32 access,
+				  gpa_t vaddr, u64 access,
 				  struct x86_exception *exception)
 {
 	if (exception)
diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
index 252c77805eb9..8621188b46df 100644
--- a/arch/x86/kvm/mmu/paging_tmpl.h
+++ b/arch/x86/kvm/mmu/paging_tmpl.h
@@ -339,7 +339,7 @@ static inline bool FNAME(is_last_gpte)(struct kvm_mmu *mmu,
  */
 static int FNAME(walk_addr_generic)(struct guest_walker *walker,
 				    struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
-				    gpa_t addr, u32 access)
+				    gpa_t addr, u64 access)
 {
 	int ret;
 	pt_element_t pte;
@@ -347,7 +347,7 @@ static int FNAME(walk_addr_generic)(struct guest_walker *walker,
 	gfn_t table_gfn;
 	u64 pt_access, pte_access;
 	unsigned index, accessed_dirty, pte_pkey;
-	unsigned nested_access;
+	u64 nested_access;
 	gpa_t pte_gpa;
 	bool have_ad;
 	int offset;
@@ -540,7 +540,7 @@ error:
 }
 
 static int FNAME(walk_addr)(struct guest_walker *walker,
-			    struct kvm_vcpu *vcpu, gpa_t addr, u32 access)
+			    struct kvm_vcpu *vcpu, gpa_t addr, u64 access)
 {
 	return FNAME(walk_addr_generic)(walker, vcpu, vcpu->arch.mmu, addr,
 					access);
@@ -988,7 +988,7 @@ static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva, hpa_t root_hpa)
 
 /* Note, @addr is a GPA when gva_to_gpa() translates an L2 GPA to an L1 GPA. */
 static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
-			       gpa_t addr, u32 access,
+			       gpa_t addr, u64 access,
 			       struct x86_exception *exception)
 {
 	struct guest_walker walker;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 89b6efb7f504..5c5be7a63b9f 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6726,7 +6726,7 @@ void kvm_get_segment(struct kvm_vcpu *vcpu,
 	static_call(kvm_x86_get_segment)(vcpu, var, seg);
 }
 
-gpa_t translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u32 access,
+gpa_t translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u64 access,
 			   struct x86_exception *exception)
 {
 	struct kvm_mmu *mmu = vcpu->arch.mmu;
@@ -6746,7 +6746,7 @@ gpa_t kvm_mmu_gva_to_gpa_read(struct kvm_vcpu *vcpu, gva_t gva,
 {
 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
 
-	u32 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
+	u64 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
 	return mmu->gva_to_gpa(vcpu, mmu, gva, access, exception);
 }
 EXPORT_SYMBOL_GPL(kvm_mmu_gva_to_gpa_read);
@@ -6756,7 +6756,7 @@ EXPORT_SYMBOL_GPL(kvm_mmu_gva_to_gpa_read);
 {
 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
 
-	u32 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
+	u64 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
 	access |= PFERR_FETCH_MASK;
 	return mmu->gva_to_gpa(vcpu, mmu, gva, access, exception);
 }
@@ -6766,7 +6766,7 @@ gpa_t kvm_mmu_gva_to_gpa_write(struct kvm_vcpu *vcpu, gva_t gva,
 {
 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
 
-	u32 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
+	u64 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
 	access |= PFERR_WRITE_MASK;
 	return mmu->gva_to_gpa(vcpu, mmu, gva, access, exception);
 }
@@ -6782,7 +6782,7 @@ gpa_t kvm_mmu_gva_to_gpa_system(struct kvm_vcpu *vcpu, gva_t gva,
 }
 
 static int kvm_read_guest_virt_helper(gva_t addr, void *val, unsigned int bytes,
-				      struct kvm_vcpu *vcpu, u32 access,
+				      struct kvm_vcpu *vcpu, u64 access,
 				      struct x86_exception *exception)
 {
 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
@@ -6819,7 +6819,7 @@ static int kvm_fetch_guest_virt(struct x86_emulate_ctxt *ctxt,
 {
 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
-	u32 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
+	u64 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
 	unsigned offset;
 	int ret;
 
@@ -6844,7 +6844,7 @@ int kvm_read_guest_virt(struct kvm_vcpu *vcpu,
 			       gva_t addr, void *val, unsigned int bytes,
 			       struct x86_exception *exception)
 {
-	u32 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
+	u64 access = (static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0;
 
 	/*
 	 * FIXME: this should call handle_emulation_failure if X86EMUL_IO_NEEDED
@@ -6863,7 +6863,7 @@ static int emulator_read_std(struct x86_emulate_ctxt *ctxt,
 			     struct x86_exception *exception, bool system)
 {
 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
-	u32 access = 0;
+	u64 access = 0;
 
 	if (!system && static_call(kvm_x86_get_cpl)(vcpu) == 3)
 		access |= PFERR_USER_MASK;
@@ -6881,7 +6881,7 @@ static int kvm_read_guest_phys_system(struct x86_emulate_ctxt *ctxt,
 }
 
 static int kvm_write_guest_virt_helper(gva_t addr, void *val, unsigned int bytes,
-				      struct kvm_vcpu *vcpu, u32 access,
+				      struct kvm_vcpu *vcpu, u64 access,
 				      struct x86_exception *exception)
 {
 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
@@ -6915,7 +6915,7 @@ static int emulator_write_std(struct x86_emulate_ctxt *ctxt, gva_t addr, void *v
 			      bool system)
 {
 	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
-	u32 access = PFERR_WRITE_MASK;
+	u64 access = PFERR_WRITE_MASK;
 
 	if (!system && static_call(kvm_x86_get_cpl)(vcpu) == 3)
 		access |= PFERR_USER_MASK;
@@ -6984,7 +6984,7 @@ static int vcpu_mmio_gva_to_gpa(struct kvm_vcpu *vcpu, unsigned long gva,
 				bool write)
 {
 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
-	u32 access = ((static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0)
+	u64 access = ((static_call(kvm_x86_get_cpl)(vcpu) == 3) ? PFERR_USER_MASK : 0)
 		| (write ? PFERR_WRITE_MASK : 0);
 
 	/*
@@ -12598,7 +12598,7 @@ void kvm_fixup_and_inject_pf_error(struct kvm_vcpu *vcpu, gva_t gva, u16 error_c
 {
 	struct kvm_mmu *mmu = vcpu->arch.walk_mmu;
 	struct x86_exception fault;
-	u32 access = error_code &
+	u64 access = error_code &
 		(PFERR_WRITE_MASK | PFERR_FETCH_MASK | PFERR_USER_MASK);
 
 	if (!(error_code & PFERR_PRESENT_MASK) ||