[PATCH 03/12] KVM: X86: Remove mmu->translate_gpa

From: Lai Jiangshan
Date: Wed Nov 24 2021 - 08:44:03 EST


From: Lai Jiangshan <laijs@xxxxxxxxxxxxxxxxx>

Reduce an indirect function call (retpoline) and some intialization
code.

Signed-off-by: Lai Jiangshan <laijs@xxxxxxxxxxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 4 ----
arch/x86/kvm/mmu.h | 13 +++++++++++++
arch/x86/kvm/mmu/mmu.c | 11 +----------
arch/x86/kvm/mmu/paging_tmpl.h | 7 +++----
arch/x86/kvm/x86.c | 4 ++--
5 files changed, 19 insertions(+), 20 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 8419aff7136f..dd16fdedc0e8 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -429,8 +429,6 @@ struct kvm_mmu {
gpa_t (*gva_to_gpa)(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
gpa_t gva_or_gpa, u32 access,
struct x86_exception *exception);
- gpa_t (*translate_gpa)(struct kvm_vcpu *vcpu, gpa_t gpa, u32 access,
- struct x86_exception *exception);
int (*sync_page)(struct kvm_vcpu *vcpu,
struct kvm_mmu_page *sp);
void (*invlpg)(struct kvm_vcpu *vcpu, gva_t gva, hpa_t root_hpa);
@@ -1764,8 +1762,6 @@ int kvm_mmu_unprotect_page(struct kvm *kvm, gfn_t gfn);
void kvm_mmu_free_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
ulong roots_to_free);
void kvm_mmu_free_guest_mode_roots(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu);
-gpa_t translate_nested_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u32 access,
- struct x86_exception *exception);
gpa_t kvm_mmu_gva_to_gpa_read(struct kvm_vcpu *vcpu, gva_t gva,
struct x86_exception *exception);
gpa_t kvm_mmu_gva_to_gpa_fetch(struct kvm_vcpu *vcpu, gva_t gva,
diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index 9ae6168d381e..97e13c2988b3 100644
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -351,4 +351,17 @@ 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,
+ struct x86_exception *exception);
+
+static inline gpa_t kvm_translate_gpa(struct kvm_vcpu *vcpu,
+ struct kvm_mmu *mmu,
+ gpa_t gpa, u32 access,
+ struct x86_exception *exception)
+{
+ if (mmu != &vcpu->arch.nested_mmu)
+ return gpa;
+ return translate_nested_gpa(vcpu, gpa, access, exception);
+}
#endif
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 3e00a54e23b6..f3aa91db4a7e 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -335,12 +335,6 @@ static bool check_mmio_spte(struct kvm_vcpu *vcpu, u64 spte)
return likely(kvm_gen == spte_gen);
}

-static gpa_t translate_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u32 access,
- struct x86_exception *exception)
-{
- return gpa;
-}
-
static int is_cpuid_PSE36(void)
{
return 1;
@@ -3734,7 +3728,7 @@ static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
{
if (exception)
exception->error_code = 0;
- return mmu->translate_gpa(vcpu, vaddr, access, exception);
+ return kvm_translate_gpa(vcpu, mmu, vaddr, access, exception);
}

static bool mmio_info_in_cache(struct kvm_vcpu *vcpu, u64 addr, bool direct)
@@ -5487,7 +5481,6 @@ static int __kvm_mmu_create(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu)

mmu->root_hpa = INVALID_PAGE;
mmu->root_pgd = 0;
- mmu->translate_gpa = translate_gpa;
for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++)
mmu->prev_roots[i] = KVM_MMU_ROOT_INFO_INVALID;

@@ -5549,8 +5542,6 @@ int kvm_mmu_create(struct kvm_vcpu *vcpu)
vcpu->arch.mmu = &vcpu->arch.root_mmu;
vcpu->arch.walk_mmu = &vcpu->arch.root_mmu;

- vcpu->arch.nested_mmu.translate_gpa = translate_nested_gpa;
-
ret = __kvm_mmu_create(vcpu, &vcpu->arch.guest_mmu);
if (ret)
return ret;
diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
index 4e203fe703b0..5c78300fc7d9 100644
--- a/arch/x86/kvm/mmu/paging_tmpl.h
+++ b/arch/x86/kvm/mmu/paging_tmpl.h
@@ -403,9 +403,8 @@ static int FNAME(walk_addr_generic)(struct guest_walker *walker,
walker->table_gfn[walker->level - 1] = table_gfn;
walker->pte_gpa[walker->level - 1] = pte_gpa;

- real_gpa = mmu->translate_gpa(vcpu, gfn_to_gpa(table_gfn),
- nested_access,
- &walker->fault);
+ real_gpa = kvm_translate_gpa(vcpu, mmu, gfn_to_gpa(table_gfn),
+ nested_access, &walker->fault);

/*
* FIXME: This can happen if emulation (for of an INS/OUTS
@@ -467,7 +466,7 @@ static int FNAME(walk_addr_generic)(struct guest_walker *walker,
if (PTTYPE == 32 && walker->level > PG_LEVEL_4K && is_cpuid_PSE36())
gfn += pse36_gfn_delta(pte);

- real_gpa = mmu->translate_gpa(vcpu, gfn_to_gpa(gfn), access, &walker->fault);
+ real_gpa = kvm_translate_gpa(vcpu, mmu, gfn_to_gpa(gfn), access, &walker->fault);
if (real_gpa == UNMAPPED_GVA)
return 0;

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 808786677b2b..25e278ba4666 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -810,8 +810,8 @@ int load_pdptrs(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu, unsigned long cr3)
* If the MMU is nested, CR3 holds an L2 GPA and needs to be translated
* to an L1 GPA.
*/
- real_gpa = mmu->translate_gpa(vcpu, gfn_to_gpa(pdpt_gfn),
- PFERR_USER_MASK | PFERR_WRITE_MASK, NULL);
+ real_gpa = kvm_translate_gpa(vcpu, mmu, gfn_to_gpa(pdpt_gfn),
+ PFERR_USER_MASK | PFERR_WRITE_MASK, NULL);
if (real_gpa == UNMAPPED_GVA)
return 0;

--
2.19.1.6.gb485710b