This adds the ability for userspace to save and restore the state of the XICS interrupt presentation controllers (ICPs) via the KVM_GET/SET_ONE_REG interface. Since there is one ICP per vcpu, we simply define a new 64-bit register in the ONE_REG space for the ICP state. The state includes the CPU priority setting, the pending IPI priority, and the priority and source number of any pending external interrupt.
Signed-off-by: Paul Mackerras <[email protected]> --- arch/powerpc/include/asm/kvm_ppc.h | 2 + arch/powerpc/include/uapi/asm/kvm.h | 11 +++++ arch/powerpc/kvm/book3s.c | 18 +++++++ arch/powerpc/kvm/book3s_xics.c | 90 +++++++++++++++++++++++++++++++++++ 4 files changed, 121 insertions(+) diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index a9ab748..d00d7c3 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -176,6 +176,8 @@ extern int kvmppc_xics_set_xive(struct kvm *kvm, u32 irq, u32 server, u32 priori extern int kvmppc_xics_get_xive(struct kvm *kvm, u32 irq, u32 *server, u32 *priority); extern int kvmppc_xics_int_on(struct kvm *kvm, u32 irq); extern int kvmppc_xics_int_off(struct kvm *kvm, u32 irq); +extern u64 kvmppc_xics_get_icp(struct kvm_vcpu *vcpu); +extern int kvmppc_xics_set_icp(struct kvm_vcpu *vcpu, u64 icpval); /* * Cuts out inst bits with ordering according to spec. diff --git a/arch/powerpc/include/uapi/asm/kvm.h b/arch/powerpc/include/uapi/asm/kvm.h index 55c1907..9fc1d11 100644 --- a/arch/powerpc/include/uapi/asm/kvm.h +++ b/arch/powerpc/include/uapi/asm/kvm.h @@ -425,4 +425,15 @@ struct kvm_book3e_206_tlb_params { #define KVM_REG_PPC_VPA_SLB (KVM_REG_PPC | KVM_REG_SIZE_U128 | 0x83) #define KVM_REG_PPC_VPA_DTL (KVM_REG_PPC | KVM_REG_SIZE_U128 | 0x84) +/* Per-vcpu interrupt controller state */ +#define KVM_REG_PPC_ICP_STATE (KVM_REG_PPC | KVM_REG_SIZE_U64 | 0x85) +#define KVM_REG_PPC_ICP_CPPR_SHIFT 56 /* current proc priority */ +#define KVM_REG_PPC_ICP_CPPR_MASK 0xff +#define KVM_REG_PPC_ICP_XISR_SHIFT 32 /* interrupt status field */ +#define KVM_REG_PPC_ICP_XISR_MASK 0xffffff +#define KVM_REG_PPC_ICP_MFRR_SHIFT 24 /* pending IPI priority */ +#define KVM_REG_PPC_ICP_MFRR_MASK 0xff +#define KVM_REG_PPC_ICP_PPRI_SHIFT 16 /* pending irq priority */ +#define KVM_REG_PPC_ICP_PPRI_MASK 0xff + #endif /* __LINUX_KVM_POWERPC_H */ diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c index c5a4478..e19232f 100644 --- a/arch/powerpc/kvm/book3s.c +++ b/arch/powerpc/kvm/book3s.c @@ -529,6 +529,15 @@ int kvm_vcpu_ioctl_get_one_reg(struct kvm_vcpu *vcpu, struct kvm_one_reg *reg) val = get_reg_val(reg->id, vcpu->arch.vscr.u[3]); break; #endif /* CONFIG_ALTIVEC */ +#ifdef CONFIG_PPC_BOOK3S_64 + case KVM_REG_PPC_ICP_STATE: + if (!vcpu->arch.icp) { + r = -ENXIO; + break; + } + val = get_reg_val(reg->id, kvmppc_xics_get_icp(vcpu)); + break; +#endif default: r = -EINVAL; break; @@ -591,6 +600,15 @@ int kvm_vcpu_ioctl_set_one_reg(struct kvm_vcpu *vcpu, struct kvm_one_reg *reg) vcpu->arch.vscr.u[3] = set_reg_val(reg->id, val); break; #endif /* CONFIG_ALTIVEC */ +#ifdef CONFIG_PPC_BOOK3S_64 + case KVM_REG_PPC_ICP_STATE: + if (!vcpu->arch.icp) { + r = -ENXIO; + break; + } + r = kvmppc_xics_set_icp(vcpu, set_reg_val(reg->id, val)); + break; +#endif default: r = -EINVAL; break; diff --git a/arch/powerpc/kvm/book3s_xics.c b/arch/powerpc/kvm/book3s_xics.c index 7b29cb8..8314cd9 100644 --- a/arch/powerpc/kvm/book3s_xics.c +++ b/arch/powerpc/kvm/book3s_xics.c @@ -976,6 +976,96 @@ void kvmppc_xics_free(struct kvm *kvm) kfree(xics); } +u64 kvmppc_xics_get_icp(struct kvm_vcpu *vcpu) +{ + struct kvmppc_icp *icp = vcpu->arch.icp; + union kvmppc_icp_state state; + + if (!icp) + return 0; + state = icp->state; + return ((u64)state.cppr << KVM_REG_PPC_ICP_CPPR_SHIFT) | + ((u64)state.xisr << KVM_REG_PPC_ICP_XISR_SHIFT) | + ((u64)state.mfrr << KVM_REG_PPC_ICP_MFRR_SHIFT) | + ((u64)state.pending_pri << KVM_REG_PPC_ICP_PPRI_SHIFT); +} + +int kvmppc_xics_set_icp(struct kvm_vcpu *vcpu, u64 icpval) +{ + struct kvmppc_icp *icp = vcpu->arch.icp; + struct kvmppc_xics *xics = vcpu->kvm->arch.xics; + union kvmppc_icp_state old_state, new_state; + struct kvmppc_ics *ics; + u8 cppr, mfrr, pending_pri; + u32 xisr; + u16 src; + bool resend; + + if (!icp || !xics) + return -ENOENT; + + cppr = icpval >> KVM_REG_PPC_ICP_CPPR_SHIFT; + xisr = (icpval >> KVM_REG_PPC_ICP_XISR_SHIFT) & + KVM_REG_PPC_ICP_XISR_MASK; + mfrr = icpval >> KVM_REG_PPC_ICP_MFRR_SHIFT; + pending_pri = icpval >> KVM_REG_PPC_ICP_PPRI_SHIFT; + + /* Require the new state to be internally consistent */ + if (xisr == 0) { + if (pending_pri != 0xff) + return -EINVAL; + } else if (xisr == XICS_IPI) { + if (pending_pri != mfrr || pending_pri >= cppr) + return -EINVAL; + } else { + if (pending_pri >= mfrr || pending_pri >= cppr) + return -EINVAL; + ics = kvmppc_xics_find_ics(xics, xisr, &src); + if (!ics) + return -EINVAL; + } + + new_state.raw = 0; + new_state.cppr = cppr; + new_state.xisr = xisr; + new_state.mfrr = mfrr; + new_state.pending_pri = pending_pri; + + /* + * Deassert the CPU interrupt request. + * icp_try_update will reassert it if necessary. + */ + kvmppc_book3s_dequeue_irqprio(icp->vcpu, + BOOK3S_INTERRUPT_EXTERNAL_LEVEL); + + /* + * Note that if we displace an interrupt from old_state.xisr, + * we don't mark it as rejected. We expect userspace to set + * the state of the interrupt sources to be consistent with + * the ICP states (either before or afterwards, which doesn't + * matter). We do handle resends due to CPPR becoming less + * favoured because that is necessary to end up with a + * consistent state in the situation where userspace restores + * the ICS states before the ICP states. + */ + do { + old_state = ACCESS_ONCE(icp->state); + + if (new_state.mfrr <= old_state.mfrr) { + resend = false; + new_state.need_resend = old_state.need_resend; + } else { + resend = old_state.need_resend; + new_state.need_resend = 0; + } + } while (!icp_try_update(icp, old_state, new_state, false)); + + if (resend) + icp_check_resend(xics, icp); + + return 0; +} + /* -- ioctls -- */ static int kvm_vm_ioctl_create_icp(struct kvm *kvm, -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
