Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751328AbaKXU5S (ORCPT ); Mon, 24 Nov 2014 15:57:18 -0500 Received: from mx1.redhat.com ([209.132.183.28]:60551 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751219AbaKXU5N (ORCPT ); Mon, 24 Nov 2014 15:57:13 -0500 Message-ID: <1416862586.11825.84.camel@bling.home> Subject: Re: [PATCH v3 8/8] KVM: arm: kvm-vfio: forwarding control From: Alex Williamson To: Eric Auger Cc: eric.auger@st.com, christoffer.dall@linaro.org, marc.zyngier@arm.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, joel.schopp@amd.com, kim.phillips@freescale.com, paulus@samba.org, gleb@kernel.org, pbonzini@redhat.com, agraf@suse.de, linux-kernel@vger.kernel.org, patches@linaro.org, will.deacon@arm.com, a.motakis@virtualopensystems.com, a.rigo@virtualopensystems.com, john.liuli@huawei.com, ming.lei@canonical.com, feng.wu@intel.com Date: Mon, 24 Nov 2014 13:56:26 -0700 In-Reply-To: <1416767760-14487-9-git-send-email-eric.auger@linaro.org> References: <1416767760-14487-1-git-send-email-eric.auger@linaro.org> <1416767760-14487-9-git-send-email-eric.auger@linaro.org> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2014-11-23 at 19:36 +0100, Eric Auger wrote: > This patch sets __KVM_HAVE_ARCH_KVM_VFIO_FORWARD and implements > kvm_arch_vfio_set_forward for ARM. > > As a result the KVM-VFIO device now allows to forward/unforward a > VFIO device IRQ on ARM. > > kvm_arch_vfio_set_forward programs both genirq and the VGIC to control > where the physical IRQ deactivation is initiated. > - forwarded case: deactivation is initiated by the guest; when it > completes the virtual IRQ, the GIC automatically deactivates the > physical IRQ. > - not forwarded case: the physical IRQ deactivation is handled by the host > > Signed-off-by: Eric Auger > > --- > > v2 -> v3: > - renaming of kvm_arch_set_fwd_state into kvm_arch_vfio_set_forward > - takes a bool arg instead of kvm_fwd_irq_action enum > - removal of KVM_VFIO_IRQ_CLEANUP > - platform device check now happens here > - more precise errors returned > - irq_eoi handled externally to this patch (VGIC) > - correct enable_irq bug done twice > - reword the commit message > - correct check of platform_bus_type > - use raw_spin_lock_irqsave and check the validity of the handler > --- > arch/arm/include/asm/kvm_host.h | 2 + > arch/arm/kvm/Makefile | 2 +- > arch/arm/kvm/kvm_vfio_arm.c | 101 ++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 104 insertions(+), 1 deletion(-) > create mode 100644 arch/arm/kvm/kvm_vfio_arm.c > > diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h > index bca5b79..447f90c 100644 > --- a/arch/arm/include/asm/kvm_host.h > +++ b/arch/arm/include/asm/kvm_host.h > @@ -27,6 +27,8 @@ > #include > #include > > +#define __KVM_HAVE_ARCH_KVM_VFIO_FORWARD > + > #if defined(CONFIG_KVM_ARM_MAX_VCPUS) > #define KVM_MAX_VCPUS CONFIG_KVM_ARM_MAX_VCPUS > #else > diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile > index ea1fa76..26a5a42 100644 > --- a/arch/arm/kvm/Makefile > +++ b/arch/arm/kvm/Makefile > @@ -19,7 +19,7 @@ kvm-arm-y = $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o $(KVM)/vf > > obj-y += kvm-arm.o init.o interrupts.o > obj-y += arm.o handle_exit.o guest.o mmu.o emulate.o reset.o > -obj-y += coproc.o coproc_a15.o coproc_a7.o mmio.o psci.o perf.o > +obj-y += coproc.o coproc_a15.o coproc_a7.o mmio.o psci.o perf.o kvm_vfio_arm.o > obj-$(CONFIG_KVM_ARM_VGIC) += $(KVM)/arm/vgic.o > obj-$(CONFIG_KVM_ARM_VGIC) += $(KVM)/arm/vgic-v2.o > obj-$(CONFIG_KVM_ARM_TIMER) += $(KVM)/arm/arch_timer.o > diff --git a/arch/arm/kvm/kvm_vfio_arm.c b/arch/arm/kvm/kvm_vfio_arm.c > new file mode 100644 > index 0000000..af2c501 > --- /dev/null > +++ b/arch/arm/kvm/kvm_vfio_arm.c > @@ -0,0 +1,101 @@ > +/* > + * Copyright (C) 2014 Linaro Ltd. > + * Authors: Eric Auger > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License, version 2, as > + * published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +/** > + * kvm_arch_vfio_set_forward - Change the forward state of an IRQ > + * > + * @fwd_irq: handle to the forward irq struct > + * @forward: target forwarding state > + * > + * If forward is true, programs genirq and VGIC so that physical IRQ > + * deactivation ownership is transferred to the guest (using GIC HW feature). > + * When forward is false, standard behavior is restored, ie. host > + * deactivates the physical IRQ. > + * returns: > + * -EINVAL if the vfio device is not a platform device > + * -ENOENT if the irq could not be identified > + * -EBUSY if physical IRQ is in progress > + * -ENOENT if the VGIC has a physical/virtual IRQ mapping that is not > + * consistent with the request. > + */ > +int kvm_arch_vfio_set_forward(struct kvm_fwd_irq *fwd_irq, > + bool forward) > +{ > + int hwirq; > + int ret = -EBUSY; > + struct irq_desc *desc; > + struct irq_data *d; > + struct platform_device *platdev; > + struct device *dev = kvm_vfio_external_base_device(fwd_irq->vdev); Just pass the dev > + unsigned long flags; > + /* > + * We don't have to garantee the vcpu handle is non void since the s/garantee/guarantee/ > + * vfio device holds a reference to the kvm struct > + */ > + struct kvm_vcpu *vcpu = kvm_get_vcpu(fwd_irq->kvm, 0); > + > + if (dev->bus == &platform_bus_type) { > + platdev = to_platform_device(dev); > + hwirq = platform_get_irq(platdev, fwd_irq->index); > + if (hwirq < 0) > + return -EINVAL; > + } else > + return -ENOENT; > + desc = irq_to_desc(hwirq); > + > + /* > + * if VFIO handler is already set, forwarded state cannot be > + * changed anymore > + */ > + raw_spin_lock_irqsave(&desc->lock, flags); > + if (desc->action) > + goto end; > + > + d = &desc->irq_data; > + > + if (forward) { > + irqd_set_irq_forwarded(d); > + raw_spin_unlock_irqrestore(&desc->lock, flags); > + ret = vgic_map_phys_irq(vcpu, > + fwd_irq->gsi + VGIC_NR_PRIVATE_IRQS, > + hwirq); > + } else { > + irqd_clr_irq_forwarded(d); > + raw_spin_unlock_irqrestore(&desc->lock, flags); > + ret = vgic_unmap_phys_irq(vcpu, > + fwd_irq->gsi + > + VGIC_NR_PRIVATE_IRQS, > + hwirq); > + } > + return ret; > + > +end: > + raw_spin_unlock_irqrestore(&desc->lock, flags); > + return ret; > +} -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/