From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoffer Dall Subject: Re: [PATCH v3 38/59] KVM: arm/arm64: vITS: Add MSI translation helpers Date: Sat, 26 Aug 2017 21:49:08 +0200 Message-ID: <20170826194908.GD11074@cbox> References: <20170731172637.29355-1-marc.zyngier@arm.com> <20170731172637.29355-39-marc.zyngier@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, Christoffer Dall , Thomas Gleixner , Jason Cooper , Eric Auger , Shanker Donthineni , Mark Rutland , Shameerali Kolothum Thodi To: Marc Zyngier Return-path: Content-Disposition: inline In-Reply-To: <20170731172637.29355-39-marc.zyngier@arm.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On Mon, Jul 31, 2017 at 06:26:16PM +0100, Marc Zyngier wrote: > The whole MSI injection process is fairly monolithic. An MSI write > gets turned into an injected LPI in one swift go. But this is actually > a more fine-grained process: > > - First, a virtual ITS gets selected using the doorbell address > - Then the DevID/EventID pair gets translated into an LPI > - Finally the LPI is injected > > Since the GICv4 code needs the first two steps in order to match > an IRQ routing entry to an LPI, let's expose them as helpers, > and refactor the existing code to use them > > Signed-off-by: Marc Zyngier > --- > virt/kvm/arm/vgic/vgic-its.c | 93 +++++++++++++++++++++++++------------------- > virt/kvm/arm/vgic/vgic.h | 4 ++ > 2 files changed, 57 insertions(+), 40 deletions(-) > > diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c > index aa6b68db80b4..fb7be8673bff 100644 > --- a/virt/kvm/arm/vgic/vgic-its.c > +++ b/virt/kvm/arm/vgic/vgic-its.c > @@ -504,15 +504,8 @@ static unsigned long vgic_mmio_read_its_idregs(struct kvm *kvm, > return 0; > } > > -/* > - * Find the target VCPU and the LPI number for a given devid/eventid pair > - * and make this IRQ pending, possibly injecting it. > - * Must be called with the its_lock mutex held. > - * Returns 0 on success, a positive error value for any ITS mapping > - * related errors and negative error values for generic errors. > - */ > -static int vgic_its_trigger_msi(struct kvm *kvm, struct vgic_its *its, > - u32 devid, u32 eventid) > +int vgic_its_resolve_lpi(struct kvm *kvm, struct vgic_its *its, > + u32 devid, u32 eventid, struct vgic_irq **irq) > { > struct kvm_vcpu *vcpu; > struct its_ite *ite; > @@ -531,26 +524,60 @@ static int vgic_its_trigger_msi(struct kvm *kvm, struct vgic_its *its, > if (!vcpu->arch.vgic_cpu.lpis_enabled) > return -EBUSY; > > - spin_lock(&ite->irq->irq_lock); > - ite->irq->pending_latch = true; > - vgic_queue_irq_unlock(kvm, ite->irq); > - > + *irq = ite->irq; > return 0; > } > > -static struct vgic_io_device *vgic_get_its_iodev(struct kvm_io_device *dev) > +struct vgic_its *vgic_msi_to_its(struct kvm *kvm, struct kvm_msi *msi) > { > + u64 address; > + struct kvm_io_device *kvm_io_dev; > struct vgic_io_device *iodev; > > - if (dev->ops != &kvm_io_gic_ops) > - return NULL; > + if (!vgic_has_its(kvm)) > + return ERR_PTR(-ENODEV); > > - iodev = container_of(dev, struct vgic_io_device, dev); > + if (!(msi->flags & KVM_MSI_VALID_DEVID)) > + return ERR_PTR(-EINVAL); > + > + address = (u64)msi->address_hi << 32 | msi->address_lo; > + > + kvm_io_dev = kvm_io_bus_get_dev(kvm, KVM_MMIO_BUS, address); > + if (!kvm_io_dev) > + return ERR_PTR(-EINVAL); > > + if (kvm_io_dev->ops != &kvm_io_gic_ops) > + return ERR_PTR(-EINVAL); > + > + iodev = container_of(kvm_io_dev, struct vgic_io_device, dev); > if (iodev->iodev_type != IODEV_ITS) > - return NULL; > + return ERR_PTR(-EINVAL); > > - return iodev; > + return iodev->its; > +} > + > +/* > + * Find the target VCPU and the LPI number for a given devid/eventid pair > + * and make this IRQ pending, possibly injecting it. > + * Must be called with the its_lock mutex held. > + * Returns 0 on success, a positive error value for any ITS mapping > + * related errors and negative error values for generic errors. > + */ > +static int vgic_its_trigger_msi(struct kvm *kvm, struct vgic_its *its, > + u32 devid, u32 eventid) > +{ > + struct vgic_irq *irq = NULL; > + int err; > + > + err = vgic_its_resolve_lpi(kvm, its, devid, eventid, &irq); > + if (err) > + return err; > + > + spin_lock(&irq->irq_lock); > + irq->pending_latch = true; > + vgic_queue_irq_unlock(kvm, irq); > + > + return 0; > } > > /* > @@ -561,30 +588,16 @@ static struct vgic_io_device *vgic_get_its_iodev(struct kvm_io_device *dev) > */ > int vgic_its_inject_msi(struct kvm *kvm, struct kvm_msi *msi) > { > - u64 address; > - struct kvm_io_device *kvm_io_dev; > - struct vgic_io_device *iodev; > + struct vgic_its *its; > int ret; > > - if (!vgic_has_its(kvm)) > - return -ENODEV; > - > - if (!(msi->flags & KVM_MSI_VALID_DEVID)) > - return -EINVAL; > - > - address = (u64)msi->address_hi << 32 | msi->address_lo; > - > - kvm_io_dev = kvm_io_bus_get_dev(kvm, KVM_MMIO_BUS, address); > - if (!kvm_io_dev) > - return -EINVAL; > + its = vgic_msi_to_its(kvm, msi); > + if (IS_ERR(its)) > + return PTR_ERR(its); > > - iodev = vgic_get_its_iodev(kvm_io_dev); > - if (!iodev) > - return -EINVAL; > - > - mutex_lock(&iodev->its->its_lock); > - ret = vgic_its_trigger_msi(kvm, iodev->its, msi->devid, msi->data); > - mutex_unlock(&iodev->its->its_lock); > + mutex_lock(&its->its_lock); > + ret = vgic_its_trigger_msi(kvm, its, msi->devid, msi->data); > + mutex_unlock(&its->its_lock); > > if (ret < 0) > return ret; > diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h > index da254ae29aec..3002b72d938b 100644 > --- a/virt/kvm/arm/vgic/vgic.h > +++ b/virt/kvm/arm/vgic/vgic.h > @@ -225,4 +225,8 @@ int vgic_debug_destroy(struct kvm *kvm); > bool lock_all_vcpus(struct kvm *kvm); > void unlock_all_vcpus(struct kvm *kvm); > > +int vgic_its_resolve_lpi(struct kvm *kvm, struct vgic_its *its, > + u32 devid, u32 eventid, struct vgic_irq **irq); > +struct vgic_its *vgic_msi_to_its(struct kvm *kvm, struct kvm_msi *msi); > + > #endif > -- > 2.11.0 > Reviewed-by: Christoffer Dall