From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Thierry Subject: [PATCH kvmtool v2 05/13] virtio: Add exit_vq() callback Date: Thu, 10 Jan 2019 14:12:42 +0000 Message-ID: <1547129570-14351-6-git-send-email-julien.thierry@arm.com> References: <1547129570-14351-1-git-send-email-julien.thierry@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: will.deacon@arm.com, kraxel@redhat.com To: kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu Return-path: In-Reply-To: <1547129570-14351-1-git-send-email-julien.thierry@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu List-Id: kvm.vger.kernel.org From: Jean-Philippe Brucker Virtio allows to reset individual virtqueues. For legacy devices, it's done by writing an address of 0 into the PFN register. Modern devices have an "enable" register. Add an exit_vq() callback to all devices. A lot more work is required by each device to clean up their virtqueue state, and by the core to reset things like MSI routes and ioeventfds. Signed-off-by: Jean-Philippe Brucker Signed-off-by: Julien Thierry --- include/kvm/virtio.h | 5 +++++ virtio/core.c | 10 ++++++++++ virtio/mmio.c | 26 ++++++++++++++++++++------ virtio/pci.c | 23 +++++++++++++++++++---- 4 files changed, 54 insertions(+), 10 deletions(-) diff --git a/include/kvm/virtio.h b/include/kvm/virtio.h index e791298..f35c74d 100644 --- a/include/kvm/virtio.h +++ b/include/kvm/virtio.h @@ -51,6 +51,7 @@ struct virt_queue { u16 last_used_signalled; u16 endian; bool use_event_idx; + bool enabled; }; /* @@ -187,6 +188,7 @@ struct virtio_ops { int (*get_vq_count)(struct kvm *kvm, void *dev); int (*init_vq)(struct kvm *kvm, void *dev, u32 vq, u32 page_size, u32 align, u32 pfn); + void (*exit_vq)(struct kvm *kvm, void *dev, u32 vq); int (*notify_vq)(struct kvm *kvm, void *dev, u32 vq); struct virt_queue *(*get_vq)(struct kvm *kvm, void *dev, u32 vq); int (*get_size_vq)(struct kvm *kvm, void *dev, u32 vq); @@ -217,8 +219,11 @@ static inline void virtio_init_device_vq(struct virtio_device *vdev, { vq->endian = vdev->endian; vq->use_event_idx = (vdev->features & VIRTIO_RING_F_EVENT_IDX); + vq->enabled = true; } +void virtio_exit_vq(struct kvm *kvm, struct virtio_device *vdev, void *dev, + int num); void virtio_set_guest_features(struct kvm *kvm, struct virtio_device *vdev, void *dev, u32 features); void virtio_notify_status(struct kvm *kvm, struct virtio_device *vdev, diff --git a/virtio/core.c b/virtio/core.c index 9114f27..67d4114 100644 --- a/virtio/core.c +++ b/virtio/core.c @@ -166,6 +166,16 @@ u16 virt_queue__get_inout_iov(struct kvm *kvm, struct virt_queue *queue, return head; } +void virtio_exit_vq(struct kvm *kvm, struct virtio_device *vdev, + void *dev, int num) +{ + struct virt_queue *vq = vdev->ops->get_vq(kvm, dev, num); + + if (vq->enabled && vdev->ops->exit_vq) + vdev->ops->exit_vq(kvm, dev, num); + memset(vq, 0, sizeof(*vq)); +} + int virtio__get_dev_specific_field(int offset, bool msix, u32 *config_off) { if (msix) { diff --git a/virtio/mmio.c b/virtio/mmio.c index 70f767e..4b8c20e 100644 --- a/virtio/mmio.c +++ b/virtio/mmio.c @@ -79,6 +79,15 @@ int virtio_mmio_signal_vq(struct kvm *kvm, struct virtio_device *vdev, u32 vq) return 0; } +static void virtio_mmio_exit_vq(struct kvm *kvm, struct virtio_device *vdev, + int vq) +{ + struct virtio_mmio *vmmio = vdev->virtio; + + ioeventfd__del_event(vmmio->addr + VIRTIO_MMIO_QUEUE_NOTIFY, vq); + virtio_exit_vq(kvm, vdev, vmmio->dev, vq); +} + int virtio_mmio_signal_config(struct kvm *kvm, struct virtio_device *vdev) { struct virtio_mmio *vmmio = vdev->virtio; @@ -188,12 +197,17 @@ static void virtio_mmio_config_out(struct kvm_cpu *vcpu, break; case VIRTIO_MMIO_QUEUE_PFN: val = ioport__read32(data); - virtio_mmio_init_ioeventfd(vmmio->kvm, vdev, vmmio->hdr.queue_sel); - vdev->ops->init_vq(vmmio->kvm, vmmio->dev, - vmmio->hdr.queue_sel, - vmmio->hdr.guest_page_size, - vmmio->hdr.queue_align, - val); + if (val) { + virtio_mmio_init_ioeventfd(vmmio->kvm, vdev, + vmmio->hdr.queue_sel); + vdev->ops->init_vq(vmmio->kvm, vmmio->dev, + vmmio->hdr.queue_sel, + vmmio->hdr.guest_page_size, + vmmio->hdr.queue_align, + val); + } else { + virtio_mmio_exit_vq(kvm, vdev, vmmio->hdr.queue_sel); + } break; case VIRTIO_MMIO_QUEUE_NOTIFY: val = ioport__read32(data); diff --git a/virtio/pci.c b/virtio/pci.c index 8add770..2da2d3f 100644 --- a/virtio/pci.c +++ b/virtio/pci.c @@ -72,6 +72,16 @@ free_ioport_evt: return r; } +static void virtio_pci_exit_vq(struct kvm *kvm, struct virtio_device *vdev, + int vq) +{ + struct virtio_pci *vpci = vdev->virtio; + + ioeventfd__del_event(vpci->port_addr + VIRTIO_PCI_QUEUE_NOTIFY, vq); + ioeventfd__del_event(vpci->mmio_addr + VIRTIO_PCI_QUEUE_NOTIFY, vq); + virtio_exit_vq(kvm, vdev, vpci->dev, vq); +} + static inline bool virtio_pci__msix_enabled(struct virtio_pci *vpci) { return vpci->pci_hdr.msix.ctrl & cpu_to_le16(PCI_MSIX_FLAGS_ENABLE); @@ -270,10 +280,15 @@ static bool virtio_pci__io_out(struct ioport *ioport, struct kvm_cpu *vcpu, u16 break; case VIRTIO_PCI_QUEUE_PFN: val = ioport__read32(data); - virtio_pci__init_ioeventfd(kvm, vdev, vpci->queue_selector); - vdev->ops->init_vq(kvm, vpci->dev, vpci->queue_selector, - 1 << VIRTIO_PCI_QUEUE_ADDR_SHIFT, - VIRTIO_PCI_VRING_ALIGN, val); + if (val) { + virtio_pci__init_ioeventfd(kvm, vdev, + vpci->queue_selector); + vdev->ops->init_vq(kvm, vpci->dev, vpci->queue_selector, + 1 << VIRTIO_PCI_QUEUE_ADDR_SHIFT, + VIRTIO_PCI_VRING_ALIGN, val); + } else { + virtio_pci_exit_vq(kvm, vdev, vpci->queue_selector); + } break; case VIRTIO_PCI_QUEUE_SEL: vpci->queue_selector = ioport__read16(data); -- 1.9.1