From patchwork Fri Aug 19 05:35:52 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Mackerras X-Patchwork-Id: 9289417 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id B8D3D6077B for ; Fri, 19 Aug 2016 05:36:47 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id AA5F029279 for ; Fri, 19 Aug 2016 05:36:47 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9F2ED2927E; Fri, 19 Aug 2016 05:36:47 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BEBED29279 for ; Fri, 19 Aug 2016 05:36:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755123AbcHSFgj (ORCPT ); Fri, 19 Aug 2016 01:36:39 -0400 Received: from ozlabs.org ([103.22.144.67]:54988 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755042AbcHSFgX (ORCPT ); Fri, 19 Aug 2016 01:36:23 -0400 Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPSA id 3sFsBw6D2Fz9t2Y; Fri, 19 Aug 2016 15:36:08 +1000 (AEST) From: Paul Mackerras To: kvm@vger.kernel.org, linuxppc-dev@ozlabs.org Cc: kvm-ppc@vger.kernel.org Subject: [PATCH 08/13] KVM: PPC: Book3S HV: Complete passthrough interrupt in host Date: Fri, 19 Aug 2016 15:35:52 +1000 Message-Id: <1471584957-21484-9-git-send-email-paulus@ozlabs.org> X-Mailer: git-send-email 2.8.1 In-Reply-To: <1471584957-21484-1-git-send-email-paulus@ozlabs.org> References: <1471584957-21484-1-git-send-email-paulus@ozlabs.org> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Suresh Warrier In existing real mode ICP code, when updating the virtual ICP state, if there is a required action that cannot be completely handled in real mode, as for instance, a VCPU needs to be woken up, flags are set in the ICP to indicate the required action. This is checked when returning from hypercalls to decide whether the call needs switch back to the host where the action can be performed in virtual mode. Note that if h_ipi_redirect is enabled, real mode code will first try to message a free host CPU to complete this job instead of returning the host to do it ourselves. Currently, the real mode PCI passthrough interrupt handling code checks if any of these flags are set and simply returns to the host. This is not good enough as the trap value (0x500) is treated as an external interrupt by the host code. It is only when the trap value is a hypercall that the host code searches for and acts on unfinished work by calling kvmppc_xics_rm_complete. This patch introduces a special trap BOOK3S_INTERRUPT_HV_RM_HARD which is returned by KVM if there is unfinished business to be completed in host virtual mode after handling a PCI passthrough interrupt. The host checks for this special interrupt condition and calls into the kvmppc_xics_rm_complete, which is made an exported function for this reason. [paulus@ozlabs.org - moved logic to set r12 to BOOK3S_INTERRUPT_HV_RM_HARD in book3s_hv_rmhandlers.S into the end of kvmppc_check_wake_reason.] Signed-off-by: Suresh Warrier Signed-off-by: Paul Mackerras --- arch/powerpc/include/asm/kvm_asm.h | 10 ++++++++++ arch/powerpc/include/asm/kvm_ppc.h | 3 +++ arch/powerpc/kvm/book3s_hv.c | 8 +++++++- arch/powerpc/kvm/book3s_hv_builtin.c | 1 + arch/powerpc/kvm/book3s_hv_rm_xics.c | 2 +- arch/powerpc/kvm/book3s_hv_rmhandlers.S | 25 +++++++++++++++++++++++++ arch/powerpc/kvm/book3s_xics.c | 3 ++- 7 files changed, 49 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_asm.h b/arch/powerpc/include/asm/kvm_asm.h index 5bca220..05cabed 100644 --- a/arch/powerpc/include/asm/kvm_asm.h +++ b/arch/powerpc/include/asm/kvm_asm.h @@ -105,6 +105,15 @@ #define BOOK3S_INTERRUPT_FAC_UNAVAIL 0xf60 #define BOOK3S_INTERRUPT_H_FAC_UNAVAIL 0xf80 +/* book3s_hv */ + +/* + * Special trap used to indicate to host that this is a + * passthrough interrupt that could not be handled + * completely in the guest. + */ +#define BOOK3S_INTERRUPT_HV_RM_HARD 0x5555 + #define BOOK3S_IRQPRIO_SYSTEM_RESET 0 #define BOOK3S_IRQPRIO_DATA_SEGMENT 1 #define BOOK3S_IRQPRIO_INST_SEGMENT 2 @@ -136,6 +145,7 @@ #define RESUME_FLAG_NV (1<<0) /* Reload guest nonvolatile state? */ #define RESUME_FLAG_HOST (1<<1) /* Resume host? */ #define RESUME_FLAG_ARCH1 (1<<2) +#define RESUME_FLAG_ARCH2 (1<<3) #define RESUME_GUEST 0 #define RESUME_GUEST_NV RESUME_FLAG_NV diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index 4299a1f..e0ada31 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -469,6 +469,7 @@ static inline struct kvmppc_passthru_irqmap *kvmppc_get_passthru_irqmap( extern void kvmppc_alloc_host_rm_ops(void); extern void kvmppc_free_host_rm_ops(void); extern void kvmppc_free_pimap(struct kvm *kvm); +extern int kvmppc_xics_rm_complete(struct kvm_vcpu *vcpu, u32 hcall); extern void kvmppc_xics_free_icp(struct kvm_vcpu *vcpu); extern int kvmppc_xics_create_icp(struct kvm_vcpu *vcpu, unsigned long server); extern int kvm_vm_ioctl_xics_irq(struct kvm *kvm, struct kvm_irq_level *args); @@ -489,6 +490,8 @@ static inline struct kvmppc_passthru_irqmap *kvmppc_get_passthru_irqmap( static inline void kvmppc_alloc_host_rm_ops(void) {}; static inline void kvmppc_free_host_rm_ops(void) {}; static inline void kvmppc_free_pimap(struct kvm *kvm) {}; +static inline int kvmppc_xics_rm_complete(struct kvm_vcpu *vcpu, u32 hcall) + { return 0; } static inline int kvmppc_xics_enabled(struct kvm_vcpu *vcpu) { return 0; } static inline void kvmppc_xics_free_icp(struct kvm_vcpu *vcpu) { } diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 175bdab..cfddafa 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -73,6 +73,8 @@ /* Used to indicate that a guest page fault needs to be handled */ #define RESUME_PAGE_FAULT (RESUME_GUEST | RESUME_FLAG_ARCH1) +/* Used to indicate that a guest passthrough interrupt needs to be handled */ +#define RESUME_PASSTHROUGH (RESUME_GUEST | RESUME_FLAG_ARCH2) /* Used as a "null" value for timebase values */ #define TB_NIL (~(u64)0) @@ -994,6 +996,9 @@ static int kvmppc_handle_exit_hv(struct kvm_run *run, struct kvm_vcpu *vcpu, kvmppc_core_queue_program(vcpu, SRR1_PROGILL); r = RESUME_GUEST; break; + case BOOK3S_INTERRUPT_HV_RM_HARD: + r = RESUME_PASSTHROUGH; + break; default: kvmppc_dump_regs(vcpu); printk(KERN_EMERG "trap=0x%x | pc=0x%lx | msr=0x%llx\n", @@ -2821,7 +2826,8 @@ static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu) r = kvmppc_book3s_hv_page_fault(run, vcpu, vcpu->arch.fault_dar, vcpu->arch.fault_dsisr); srcu_read_unlock(&vcpu->kvm->srcu, srcu_idx); - } + } else if (r == RESUME_PASSTHROUGH) + r = kvmppc_xics_rm_complete(vcpu, 0); } while (is_kvmppc_resume_guest(r)); out: diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c index fdb8aef..a262957 100644 --- a/arch/powerpc/kvm/book3s_hv_builtin.c +++ b/arch/powerpc/kvm/book3s_hv_builtin.c @@ -321,6 +321,7 @@ static struct kvmppc_irq_map *get_irqmap(struct kvmppc_passthru_irqmap *pimap, * Returns: * 0 if no interrupt is pending * 1 if an interrupt is pending that needs to be handled by the host + * 2 Passthrough that needs completion in the host * -1 if there was a guest wakeup IPI (which has now been cleared) * -2 if there is PCI passthrough external interrupt that was handled */ diff --git a/arch/powerpc/kvm/book3s_hv_rm_xics.c b/arch/powerpc/kvm/book3s_hv_rm_xics.c index 17f5b85..3b8d7ac 100644 --- a/arch/powerpc/kvm/book3s_hv_rm_xics.c +++ b/arch/powerpc/kvm/book3s_hv_rm_xics.c @@ -751,7 +751,7 @@ long kvmppc_deliver_irq_passthru(struct kvm_vcpu *vcpu, icp_eoi(irq_desc_get_chip(irq_map->desc), irq_map->r_hwirq, xirr); if (check_too_hard(xics, icp) == H_TOO_HARD) - return 1; + return 2; else return -2; } diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index 12fb2af..7cc924b 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -1189,6 +1189,11 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) * 1 An interrupt is pending that needs to be handled by the host * Exit guest and return to host by branching to guest_exit_cont * + * 2 Passthrough that needs completion in the host + * Exit guest and return to host by branching to guest_exit_cont + * However, we also set r12 to BOOK3S_INTERRUPT_HV_RM_HARD + * to indicate to the host to complete handling the interrupt + * * Before returning to guest, we check if any CPU is heading out * to the host and if so, we head out also. If no CPUs are heading * check return values <= 0. @@ -1204,6 +1209,15 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) * Return to guest to deliver any pending guest interrupts. */ + cmpdi r3, 1 + ble 1f + + /* Return code = 2 */ + li r12, BOOK3S_INTERRUPT_HV_RM_HARD + stw r12, VCPU_TRAP(r9) + b guest_exit_cont + +1: /* Return code <= 1 */ cmpdi r3, 0 bgt guest_exit_cont @@ -2419,6 +2433,17 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) bl kvmppc_read_intr nop li r12, BOOK3S_INTERRUPT_EXTERNAL + cmpdi r3, 1 + ble 1f + + /* + * Return code of 2 means PCI passthrough interrupt, but + * we need to return back to host to complete handling the + * interrupt. Trap reason is expected in r12 by guest + * exit code. + */ + li r12, BOOK3S_INTERRUPT_HV_RM_HARD +1: ld r0, PPC_MIN_STKFRM+PPC_LR_STKOFF(r1) addi r1, r1, PPC_MIN_STKFRM mtlr r0 diff --git a/arch/powerpc/kvm/book3s_xics.c b/arch/powerpc/kvm/book3s_xics.c index 05aa113..d528d22 100644 --- a/arch/powerpc/kvm/book3s_xics.c +++ b/arch/powerpc/kvm/book3s_xics.c @@ -812,7 +812,7 @@ static noinline int kvmppc_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr) return H_SUCCESS; } -static noinline int kvmppc_xics_rm_complete(struct kvm_vcpu *vcpu, u32 hcall) +int kvmppc_xics_rm_complete(struct kvm_vcpu *vcpu, u32 hcall) { struct kvmppc_xics *xics = vcpu->kvm->arch.xics; struct kvmppc_icp *icp = vcpu->arch.icp; @@ -841,6 +841,7 @@ static noinline int kvmppc_xics_rm_complete(struct kvm_vcpu *vcpu, u32 hcall) return H_SUCCESS; } +EXPORT_SYMBOL_GPL(kvmppc_xics_rm_complete); int kvmppc_xics_hcall(struct kvm_vcpu *vcpu, u32 req) {