From b37fbea6cefc3a8ff7b6cfec9867432d1a10046d Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Fri, 7 Jun 2013 16:51:25 +0800 Subject: KVM: MMU: make return value of mmio page fault handler more readable Define some meaningful names instead of raw code Signed-off-by: Xiao Guangrong Reviewed-by: Gleb Natapov Reviewed-by: Marcelo Tosatti Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu.c | 15 +++++---------- arch/x86/kvm/mmu.h | 14 ++++++++++++++ arch/x86/kvm/vmx.c | 4 ++-- 3 files changed, 21 insertions(+), 12 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 5d9a1fb108f5..476d155834b9 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -3224,17 +3224,12 @@ static u64 walk_shadow_page_get_mmio_spte(struct kvm_vcpu *vcpu, u64 addr) return spte; } -/* - * If it is a real mmio page fault, return 1 and emulat the instruction - * directly, return 0 to let CPU fault again on the address, -1 is - * returned if bug is detected. - */ int handle_mmio_page_fault_common(struct kvm_vcpu *vcpu, u64 addr, bool direct) { u64 spte; if (quickly_check_mmio_pf(vcpu, addr, direct)) - return 1; + return RET_MMIO_PF_EMULATE; spte = walk_shadow_page_get_mmio_spte(vcpu, addr); @@ -3247,7 +3242,7 @@ int handle_mmio_page_fault_common(struct kvm_vcpu *vcpu, u64 addr, bool direct) trace_handle_mmio_page_fault(addr, gfn, access); vcpu_cache_mmio_info(vcpu, addr, gfn, access); - return 1; + return RET_MMIO_PF_EMULATE; } /* @@ -3255,13 +3250,13 @@ int handle_mmio_page_fault_common(struct kvm_vcpu *vcpu, u64 addr, bool direct) * it's a BUG if the gfn is not a mmio page. */ if (direct && !check_direct_spte_mmio_pf(spte)) - return -1; + return RET_MMIO_PF_BUG; /* * If the page table is zapped by other cpus, let CPU fault again on * the address. */ - return 0; + return RET_MMIO_PF_RETRY; } EXPORT_SYMBOL_GPL(handle_mmio_page_fault_common); @@ -3271,7 +3266,7 @@ static int handle_mmio_page_fault(struct kvm_vcpu *vcpu, u64 addr, int ret; ret = handle_mmio_page_fault_common(vcpu, addr, direct); - WARN_ON(ret < 0); + WARN_ON(ret == RET_MMIO_PF_BUG); return ret; } diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h index 922bfae77c58..ba6a19c50f27 100644 --- a/arch/x86/kvm/mmu.h +++ b/arch/x86/kvm/mmu.h @@ -52,6 +52,20 @@ int kvm_mmu_get_spte_hierarchy(struct kvm_vcpu *vcpu, u64 addr, u64 sptes[4]); void kvm_mmu_set_mmio_spte_mask(u64 mmio_mask); + +/* + * Return values of handle_mmio_page_fault_common: + * RET_MMIO_PF_EMULATE: it is a real mmio page fault, emulate the instruction + * directly. + * RET_MMIO_PF_RETRY: let CPU fault again on the address. + * RET_MMIO_PF_BUG: bug is detected. + */ +enum { + RET_MMIO_PF_EMULATE = 1, + RET_MMIO_PF_RETRY = 0, + RET_MMIO_PF_BUG = -1 +}; + int handle_mmio_page_fault_common(struct kvm_vcpu *vcpu, u64 addr, bool direct); int kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, struct kvm_mmu *context); diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 78ee123de7a3..85c8d51dcbe7 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -5366,10 +5366,10 @@ static int handle_ept_misconfig(struct kvm_vcpu *vcpu) gpa = vmcs_read64(GUEST_PHYSICAL_ADDRESS); ret = handle_mmio_page_fault_common(vcpu, gpa, true); - if (likely(ret == 1)) + if (likely(ret == RET_MMIO_PF_EMULATE)) return x86_emulate_instruction(vcpu, gpa, 0, NULL, 0) == EMULATE_DONE; - if (unlikely(!ret)) + if (unlikely(ret == RET_MMIO_PF_RETRY)) return 1; /* It is the real ept misconfig */ -- cgit v1.2.2