From 81c52c56e2b43589091ee29038bcf793d3f184ab Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Tue, 16 Oct 2012 20:10:59 +0800 Subject: [PATCH] KVM: do not treat noslot pfn as a error pfn This patch filters noslot pfn out from error pfns based on Marcelo comment: noslot pfn is not a error pfn After this patch, - is_noslot_pfn indicates that the gfn is not in slot - is_error_pfn indicates that the gfn is in slot but the error is occurred when translate the gfn to pfn - is_error_noslot_pfn indicates that the pfn either it is error pfns or it is noslot pfn And is_invalid_pfn can be removed, it makes the code more clean Signed-off-by: Xiao Guangrong Signed-off-by: Marcelo Tosatti --- arch/powerpc/kvm/book3s_32_mmu_host.c | 2 +- arch/powerpc/kvm/book3s_64_mmu_host.c | 2 +- arch/powerpc/kvm/e500_tlb.c | 2 +- arch/x86/kvm/mmu.c | 4 ++-- arch/x86/kvm/paging_tmpl.h | 2 +- arch/x86/kvm/x86.c | 2 +- include/linux/kvm_host.h | 28 +++++++++++++++++++-------- virt/kvm/iommu.c | 4 ++-- virt/kvm/kvm_main.c | 6 +++--- 9 files changed, 32 insertions(+), 20 deletions(-) diff --git a/arch/powerpc/kvm/book3s_32_mmu_host.c b/arch/powerpc/kvm/book3s_32_mmu_host.c index d1107a9b5d13..00e619bf608e 100644 --- a/arch/powerpc/kvm/book3s_32_mmu_host.c +++ b/arch/powerpc/kvm/book3s_32_mmu_host.c @@ -155,7 +155,7 @@ int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *orig_pte) /* Get host physical address for gpa */ hpaddr = kvmppc_gfn_to_pfn(vcpu, orig_pte->raddr >> PAGE_SHIFT); - if (is_error_pfn(hpaddr)) { + if (is_error_noslot_pfn(hpaddr)) { printk(KERN_INFO "Couldn't get guest page for gfn %lx!\n", orig_pte->eaddr); r = -EINVAL; diff --git a/arch/powerpc/kvm/book3s_64_mmu_host.c b/arch/powerpc/kvm/book3s_64_mmu_host.c index d0205a545a81..ead58e317294 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_host.c +++ b/arch/powerpc/kvm/book3s_64_mmu_host.c @@ -93,7 +93,7 @@ int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *orig_pte) /* Get host physical address for gpa */ hpaddr = kvmppc_gfn_to_pfn(vcpu, orig_pte->raddr >> PAGE_SHIFT); - if (is_error_pfn(hpaddr)) { + if (is_error_noslot_pfn(hpaddr)) { printk(KERN_INFO "Couldn't get guest page for gfn %lx!\n", orig_pte->eaddr); r = -EINVAL; goto out; diff --git a/arch/powerpc/kvm/e500_tlb.c b/arch/powerpc/kvm/e500_tlb.c index c73389477d17..6305ee692ef7 100644 --- a/arch/powerpc/kvm/e500_tlb.c +++ b/arch/powerpc/kvm/e500_tlb.c @@ -524,7 +524,7 @@ static inline void kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500, if (likely(!pfnmap)) { unsigned long tsize_pages = 1 << (tsize + 10 - PAGE_SHIFT); pfn = gfn_to_pfn_memslot(slot, gfn); - if (is_error_pfn(pfn)) { + if (is_error_noslot_pfn(pfn)) { printk(KERN_ERR "Couldn't get real page for gfn %lx!\n", (long)gfn); return; diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index aabb1289ff04..b875a9ed9b8e 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -2699,7 +2699,7 @@ static void transparent_hugepage_adjust(struct kvm_vcpu *vcpu, * PT_PAGE_TABLE_LEVEL and there would be no adjustment done * here. */ - if (!is_error_pfn(pfn) && !kvm_is_mmio_pfn(pfn) && + if (!is_error_noslot_pfn(pfn) && !kvm_is_mmio_pfn(pfn) && level == PT_PAGE_TABLE_LEVEL && PageTransCompound(pfn_to_page(pfn)) && !has_wrprotected_page(vcpu->kvm, gfn, PT_DIRECTORY_LEVEL)) { @@ -2733,7 +2733,7 @@ static bool handle_abnormal_pfn(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn, bool ret = true; /* The pfn is invalid, report the error! */ - if (unlikely(is_invalid_pfn(pfn))) { + if (unlikely(is_error_pfn(pfn))) { *ret_val = kvm_handle_bad_page(vcpu, gfn, pfn); goto exit; } diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index d17decaf1db9..891eb6d93b8b 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -323,7 +323,7 @@ FNAME(prefetch_gpte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, protect_clean_gpte(&pte_access, gpte); pfn = pte_prefetch_gfn_to_pfn(vcpu, gfn, no_dirty_log && (pte_access & ACC_WRITE_MASK)); - if (is_invalid_pfn(pfn)) + if (is_error_pfn(pfn)) return false; /* diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 6e5f069bee30..49fa1f0e59bd 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4504,7 +4504,7 @@ static bool reexecute_instruction(struct kvm_vcpu *vcpu, gva_t gva) * instruction -> ... */ pfn = gfn_to_pfn(vcpu->kvm, gpa_to_gfn(gpa)); - if (!is_error_pfn(pfn)) { + if (!is_error_noslot_pfn(pfn)) { kvm_release_pfn_clean(pfn); return true; } diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 82e2c783a21e..99a47627e046 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -58,28 +58,40 @@ /* * For the normal pfn, the highest 12 bits should be zero, - * so we can mask these bits to indicate the error. + * so we can mask bit 62 ~ bit 52 to indicate the error pfn, + * mask bit 63 to indicate the noslot pfn. */ -#define KVM_PFN_ERR_MASK (0xfffULL << 52) +#define KVM_PFN_ERR_MASK (0x7ffULL << 52) +#define KVM_PFN_ERR_NOSLOT_MASK (0xfffULL << 52) +#define KVM_PFN_NOSLOT (0x1ULL << 63) #define KVM_PFN_ERR_FAULT (KVM_PFN_ERR_MASK) #define KVM_PFN_ERR_HWPOISON (KVM_PFN_ERR_MASK + 1) -#define KVM_PFN_ERR_BAD (KVM_PFN_ERR_MASK + 2) -#define KVM_PFN_ERR_RO_FAULT (KVM_PFN_ERR_MASK + 3) +#define KVM_PFN_ERR_RO_FAULT (KVM_PFN_ERR_MASK + 2) +/* + * error pfns indicate that the gfn is in slot but faild to + * translate it to pfn on host. + */ static inline bool is_error_pfn(pfn_t pfn) { return !!(pfn & KVM_PFN_ERR_MASK); } -static inline bool is_noslot_pfn(pfn_t pfn) +/* + * error_noslot pfns indicate that the gfn can not be + * translated to pfn - it is not in slot or failed to + * translate it to pfn. + */ +static inline bool is_error_noslot_pfn(pfn_t pfn) { - return pfn == KVM_PFN_ERR_BAD; + return !!(pfn & KVM_PFN_ERR_NOSLOT_MASK); } -static inline bool is_invalid_pfn(pfn_t pfn) +/* noslot pfn indicates that the gfn is not in slot. */ +static inline bool is_noslot_pfn(pfn_t pfn) { - return !is_noslot_pfn(pfn) && is_error_pfn(pfn); + return pfn == KVM_PFN_NOSLOT; } #define KVM_HVA_ERR_BAD (PAGE_OFFSET) diff --git a/virt/kvm/iommu.c b/virt/kvm/iommu.c index 18e1e30019e3..4a340cb23013 100644 --- a/virt/kvm/iommu.c +++ b/virt/kvm/iommu.c @@ -52,7 +52,7 @@ static pfn_t kvm_pin_pages(struct kvm_memory_slot *slot, gfn_t gfn, end_gfn = gfn + (size >> PAGE_SHIFT); gfn += 1; - if (is_error_pfn(pfn)) + if (is_error_noslot_pfn(pfn)) return pfn; while (gfn < end_gfn) @@ -106,7 +106,7 @@ int kvm_iommu_map_pages(struct kvm *kvm, struct kvm_memory_slot *slot) * important because we unmap and unpin in 4kb steps later. */ pfn = kvm_pin_pages(slot, gfn, page_size); - if (is_error_pfn(pfn)) { + if (is_error_noslot_pfn(pfn)) { gfn += 1; continue; } diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index be70035fd42a..2fb73191801f 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1208,7 +1208,7 @@ __gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn, bool atomic, return KVM_PFN_ERR_RO_FAULT; if (kvm_is_error_hva(addr)) - return KVM_PFN_ERR_BAD; + return KVM_PFN_NOSLOT; /* Do not map writable pfn in the readonly memslot. */ if (writable && memslot_is_readonly(slot)) { @@ -1290,7 +1290,7 @@ EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic); static struct page *kvm_pfn_to_page(pfn_t pfn) { - if (is_error_pfn(pfn)) + if (is_error_noslot_pfn(pfn)) return KVM_ERR_PTR_BAD_PAGE; if (kvm_is_mmio_pfn(pfn)) { @@ -1322,7 +1322,7 @@ EXPORT_SYMBOL_GPL(kvm_release_page_clean); void kvm_release_pfn_clean(pfn_t pfn) { - if (!is_error_pfn(pfn) && !kvm_is_mmio_pfn(pfn)) + if (!is_error_noslot_pfn(pfn) && !kvm_is_mmio_pfn(pfn)) put_page(pfn_to_page(pfn)); } EXPORT_SYMBOL_GPL(kvm_release_pfn_clean); -- 2.20.1