From 023c3c96ca4d196c09d554d5a98900406e4d7ecb Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Fri, 28 May 2021 19:07:28 +1000 Subject: [PATCH] KVM: PPC: Book3S HV P9: implement kvmppc_xive_pull_vcpu in C MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit This is more symmetric with kvmppc_xive_push_vcpu, and has the advantage that it runs with the MMU on. The extra test added to the asm will go away with a future change. Signed-off-by: Nicholas Piggin Reviewed-by: Cédric Le Goater Reviewed-by: Alexey Kardashevskiy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210528090752.3542186-9-npiggin@gmail.com --- arch/powerpc/include/asm/kvm_ppc.h | 2 ++ arch/powerpc/kvm/book3s_hv.c | 2 ++ arch/powerpc/kvm/book3s_hv_rmhandlers.S | 5 +++++ arch/powerpc/kvm/book3s_xive.c | 31 +++++++++++++++++++++++++++++++ 4 files changed, 40 insertions(+) diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index 5bf8ae9..8c10c34 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -671,6 +671,7 @@ extern int kvmppc_xive_set_icp(struct kvm_vcpu *vcpu, u64 icpval); extern int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level, bool line_status); extern void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu); +extern void kvmppc_xive_pull_vcpu(struct kvm_vcpu *vcpu); static inline int kvmppc_xive_enabled(struct kvm_vcpu *vcpu) { @@ -711,6 +712,7 @@ static inline int kvmppc_xive_set_icp(struct kvm_vcpu *vcpu, u64 icpval) { retur static inline int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level, bool line_status) { return -ENODEV; } static inline void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu) { } +static inline void kvmppc_xive_pull_vcpu(struct kvm_vcpu *vcpu) { } static inline int kvmppc_xive_enabled(struct kvm_vcpu *vcpu) { return 0; } diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 13728495..907963b 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -3570,6 +3570,8 @@ static int kvmhv_load_hv_regs_and_go(struct kvm_vcpu *vcpu, u64 time_limit, trap = __kvmhv_vcpu_entry_p9(vcpu); + kvmppc_xive_pull_vcpu(vcpu); + /* Advance host PURR/SPURR by the amount used by guest */ purr = mfspr(SPRN_PURR); spurr = mfspr(SPRN_SPURR); diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index a8abe79..55d4d54 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -1445,6 +1445,11 @@ guest_exit_cont: /* r9 = vcpu, r12 = trap, r13 = paca */ bl kvmhv_accumulate_time #endif #ifdef CONFIG_KVM_XICS + /* If we came in through the P9 short path, xive pull is done in C */ + lwz r0, STACK_SLOT_SHORT_PATH(r1) + cmpwi r0, 0 + bne 1f + /* We are exiting, pull the VP from the XIVE */ lbz r0, VCPU_XIVE_PUSHED(r9) cmpwi cr0, r0, 0 diff --git a/arch/powerpc/kvm/book3s_xive.c b/arch/powerpc/kvm/book3s_xive.c index e7219b6..741bf1f 100644 --- a/arch/powerpc/kvm/book3s_xive.c +++ b/arch/powerpc/kvm/book3s_xive.c @@ -128,6 +128,37 @@ void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu) EXPORT_SYMBOL_GPL(kvmppc_xive_push_vcpu); /* + * Pull a vcpu's context from the XIVE on guest exit. + * This assumes we are in virtual mode (MMU on) + */ +void kvmppc_xive_pull_vcpu(struct kvm_vcpu *vcpu) +{ + void __iomem *tima = local_paca->kvm_hstate.xive_tima_virt; + + if (!vcpu->arch.xive_pushed) + return; + + /* + * Should not have been pushed if there is no tima + */ + if (WARN_ON(!tima)) + return; + + eieio(); + /* First load to pull the context, we ignore the value */ + __raw_readl(tima + TM_SPC_PULL_OS_CTX); + /* Second load to recover the context state (Words 0 and 1) */ + vcpu->arch.xive_saved_state.w01 = __raw_readq(tima + TM_QW1_OS); + + /* Fixup some of the state for the next load */ + vcpu->arch.xive_saved_state.lsmfb = 0; + vcpu->arch.xive_saved_state.ack = 0xff; + vcpu->arch.xive_pushed = 0; + eieio(); +} +EXPORT_SYMBOL_GPL(kvmppc_xive_pull_vcpu); + +/* * This is a simple trigger for a generic XIVE IRQ. This must * only be called for interrupts that support a trigger page */ -- 2.7.4