[RFC PATCH 02/10] KVM: x86/mmu: make kvm_mmu:page_fault receive single argument

From: Isaku Yamahata
Date: Tue Apr 20 2021 - 06:42:06 EST


Convert kvm_mmu:page_fault callback to receive struct kvm_page_fault
instead of many arguments.
The following functions are converted by this patch.
kvm_tdp_page_fault(), nonpaging_page_fault() and, FNAME(page_fault).

No functional change is intended.

Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 4 ++--
arch/x86/kvm/mmu.h | 9 +++------
arch/x86/kvm/mmu/mmu.c | 19 ++++++++++---------
arch/x86/kvm/mmu/paging_tmpl.h | 7 +++++--
4 files changed, 20 insertions(+), 19 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 3768819693e5..97e72076f358 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -351,6 +351,7 @@ struct kvm_mmu_root_info {
#define KVM_HAVE_MMU_RWLOCK

struct kvm_mmu_page;
+struct kvm_page_fault;

/*
* x86 supports 4 paging modes (5-level 64-bit, 4-level 64-bit, 3-level 32-bit,
@@ -360,8 +361,7 @@ struct kvm_mmu_page;
struct kvm_mmu {
unsigned long (*get_guest_pgd)(struct kvm_vcpu *vcpu);
u64 (*get_pdptr)(struct kvm_vcpu *vcpu, int index);
- int (*page_fault)(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u32 err,
- bool prefault);
+ int (*page_fault)(struct kvm_page_fault *kpf);
void (*inject_page_fault)(struct kvm_vcpu *vcpu,
struct x86_exception *fault);
gpa_t (*gva_to_gpa)(struct kvm_vcpu *vcpu, gpa_t gva_or_gpa,
diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h
index 245c5d7fd3dd..7fcd9c147e63 100644
--- a/arch/x86/kvm/mmu.h
+++ b/arch/x86/kvm/mmu.h
@@ -124,18 +124,15 @@ static inline void kvm_page_fault_init(
kpf->prefault = prefault;
}

-int kvm_tdp_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
- bool prefault);
+int kvm_tdp_page_fault(struct kvm_page_fault *kpf);

static inline int kvm_mmu_do_page_fault(struct kvm_page_fault *kpf)
{
#ifdef CONFIG_RETPOLINE
if (likely(kpf->vcpu->arch.mmu->page_fault == kvm_tdp_page_fault))
- return kvm_tdp_page_fault(kpf->vcpu, kpf->cr2_or_gpa,
- kpf->error_code, kpf->prefault);
+ return kvm_tdp_page_fault(kpf);
#endif
- return kpf->vcpu->arch.mmu->page_fault(kpf->vcpu, kpf->cr2_or_gpa,
- kpf->error_code, kpf->prefault);
+ return kpf->vcpu->arch.mmu->page_fault(kpf);
}

/*
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 8ea2afcb528c..46998cfabfd3 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -3745,14 +3745,15 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
return r;
}

-static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa,
- u32 error_code, bool prefault)
+static int nonpaging_page_fault(struct kvm_page_fault *kpf)
{
- pgprintk("%s: gva %lx error %x\n", __func__, gpa, error_code);
+ pgprintk("%s: gva %lx error %x\n", __func__,
+ kpf->cr2_or_gpa, kpf->error_code);

/* This path builds a PAE pagetable, we can map 2mb pages at maximum. */
- return direct_page_fault(vcpu, gpa & PAGE_MASK, error_code, prefault,
- PG_LEVEL_2M, false);
+ return direct_page_fault(kpf->vcpu, kpf->cr2_or_gpa & PAGE_MASK,
+ kpf->error_code,
+ kpf->prefault, PG_LEVEL_2M, false);
}

int kvm_handle_page_fault(struct kvm_vcpu *vcpu, u64 error_code,
@@ -3788,9 +3789,9 @@ int kvm_handle_page_fault(struct kvm_vcpu *vcpu, u64 error_code,
}
EXPORT_SYMBOL_GPL(kvm_handle_page_fault);

-int kvm_tdp_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
- bool prefault)
+int kvm_tdp_page_fault(struct kvm_page_fault *kpf)
{
+ u32 gpa = kpf->cr2_or_gpa;
int max_level;

for (max_level = KVM_MAX_HUGEPAGE_LEVEL;
@@ -3799,11 +3800,11 @@ int kvm_tdp_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
int page_num = KVM_PAGES_PER_HPAGE(max_level);
gfn_t base = (gpa >> PAGE_SHIFT) & ~(page_num - 1);

- if (kvm_mtrr_check_gfn_range_consistency(vcpu, base, page_num))
+ if (kvm_mtrr_check_gfn_range_consistency(kpf->vcpu, base, page_num))
break;
}

- return direct_page_fault(vcpu, gpa, error_code, prefault,
+ return direct_page_fault(kpf->vcpu, gpa, kpf->error_code, kpf->prefault,
max_level, true);
}

diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
index 55d7b473ac44..dc814463a8df 100644
--- a/arch/x86/kvm/mmu/paging_tmpl.h
+++ b/arch/x86/kvm/mmu/paging_tmpl.h
@@ -789,9 +789,12 @@ FNAME(is_self_change_mapping)(struct kvm_vcpu *vcpu,
* Returns: 1 if we need to emulate the instruction, 0 otherwise, or
* a negative value on error.
*/
-static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gpa_t addr, u32 error_code,
- bool prefault)
+static int FNAME(page_fault)(struct kvm_page_fault *kpf)
{
+ struct kvm_vcpu *vcpu = kpf->vcpu;
+ gpa_t addr = kpf->cr2_or_gpa;
+ u32 error_code = kpf->error_code;
+ bool prefault = kpf->prefault;
bool write_fault = error_code & PFERR_WRITE_MASK;
bool user_fault = error_code & PFERR_USER_MASK;
struct guest_walker walker;
--
2.25.1