From c12fb43c2f6d6a57a4e21afe74ff56485d699ee7 Mon Sep 17 00:00:00 2001 From: Alexander Graf Date: Fri, 20 Jun 2014 14:43:36 +0200 Subject: [PATCH] KVM: PPC: Handle magic page in kvmppc_ld/st We use kvmppc_ld and kvmppc_st to emulate load/store instructions that may as well access the magic page. Special case it out so that we can properly access it. Signed-off-by: Alexander Graf --- arch/powerpc/include/asm/kvm_book3s.h | 7 +++++++ arch/powerpc/include/asm/kvm_booke.h | 10 ++++++++++ arch/powerpc/kvm/powerpc.c | 22 ++++++++++++++++++++++ 3 files changed, 39 insertions(+) diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h index 172fd6dd2821..61667913ec98 100644 --- a/arch/powerpc/include/asm/kvm_book3s.h +++ b/arch/powerpc/include/asm/kvm_book3s.h @@ -286,6 +286,13 @@ static inline bool is_kvmppc_resume_guest(int r) return (r == RESUME_GUEST || r == RESUME_GUEST_NV); } +static inline bool is_kvmppc_hv_enabled(struct kvm *kvm); +static inline bool kvmppc_supports_magic_page(struct kvm_vcpu *vcpu) +{ + /* Only PR KVM supports the magic page */ + return !is_kvmppc_hv_enabled(vcpu->kvm); +} + /* Magic register values loaded into r3 and r4 before the 'sc' assembly * instruction for the OSI hypercalls */ #define OSI_SC_MAGIC_R3 0x113724FA diff --git a/arch/powerpc/include/asm/kvm_booke.h b/arch/powerpc/include/asm/kvm_booke.h index cbb19906ca36..f7aa5cc395c4 100644 --- a/arch/powerpc/include/asm/kvm_booke.h +++ b/arch/powerpc/include/asm/kvm_booke.h @@ -103,4 +103,14 @@ static inline ulong kvmppc_get_fault_dar(struct kvm_vcpu *vcpu) { return vcpu->arch.fault_dear; } + +static inline bool kvmppc_supports_magic_page(struct kvm_vcpu *vcpu) +{ + /* Magic page is only supported on e500v2 */ +#ifdef CONFIG_KVM_E500V2 + return true; +#else + return false; +#endif +} #endif /* __ASM_KVM_BOOKE_H__ */ diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index be40886e8f0a..544d1d30c8cc 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -312,6 +312,7 @@ EXPORT_SYMBOL_GPL(kvmppc_emulate_mmio); int kvmppc_st(struct kvm_vcpu *vcpu, ulong *eaddr, int size, void *ptr, bool data) { + ulong mp_pa = vcpu->arch.magic_page_pa & KVM_PAM & PAGE_MASK; struct kvmppc_pte pte; int r; @@ -327,6 +328,16 @@ int kvmppc_st(struct kvm_vcpu *vcpu, ulong *eaddr, int size, void *ptr, if (!pte.may_write) return -EPERM; + /* Magic page override */ + if (kvmppc_supports_magic_page(vcpu) && mp_pa && + ((pte.raddr & KVM_PAM & PAGE_MASK) == mp_pa) && + !(kvmppc_get_msr(vcpu) & MSR_PR)) { + void *magic = vcpu->arch.shared; + magic += pte.eaddr & 0xfff; + memcpy(magic, ptr, size); + return EMULATE_DONE; + } + if (kvm_write_guest(vcpu->kvm, pte.raddr, ptr, size)) return EMULATE_DO_MMIO; @@ -337,6 +348,7 @@ EXPORT_SYMBOL_GPL(kvmppc_st); int kvmppc_ld(struct kvm_vcpu *vcpu, ulong *eaddr, int size, void *ptr, bool data) { + ulong mp_pa = vcpu->arch.magic_page_pa & KVM_PAM & PAGE_MASK; struct kvmppc_pte pte; int rc; @@ -355,6 +367,16 @@ int kvmppc_ld(struct kvm_vcpu *vcpu, ulong *eaddr, int size, void *ptr, if (!data && !pte.may_execute) return -ENOEXEC; + /* Magic page override */ + if (kvmppc_supports_magic_page(vcpu) && mp_pa && + ((pte.raddr & KVM_PAM & PAGE_MASK) == mp_pa) && + !(kvmppc_get_msr(vcpu) & MSR_PR)) { + void *magic = vcpu->arch.shared; + magic += pte.eaddr & 0xfff; + memcpy(ptr, magic, size); + return EMULATE_DONE; + } + if (kvm_read_guest(vcpu->kvm, pte.raddr, ptr, size)) return EMULATE_DO_MMIO; -- GitLab