This patch implements basic MSI-X support for virtio-rng. The device uses the virtio preferred method of working with MSI-X by creating one vector for configuration and one vector for each vq in the device.
Signed-off-by: Sasha Levin <[email protected]> --- tools/kvm/include/kvm/pci.h | 16 +++++++++++++ tools/kvm/virtio/rng.c | 53 ++++++++++++++++++++++++++++++++++++++---- 2 files changed, 64 insertions(+), 5 deletions(-) diff --git a/tools/kvm/include/kvm/pci.h b/tools/kvm/include/kvm/pci.h index a7532e3..27fa349 100644 --- a/tools/kvm/include/kvm/pci.h +++ b/tools/kvm/include/kvm/pci.h @@ -24,6 +24,21 @@ struct pci_config_address { unsigned enable_bit : 1; /* 31 */ }; +struct msix_table { + u32 low; + u32 high; + u32 data; + u32 ctrl; +}; + +struct msix_cap { + u8 cap; + u8 next; + u16 table_size; + u32 table_offset; + struct msix_table table[3 * PCI_MSIX_ENTRY_SIZE]; +}; + struct pci_device_header { u16 vendor_id; u16 device_id; @@ -47,6 +62,7 @@ struct pci_device_header { u8 irq_pin; u8 min_gnt; u8 max_lat; + struct msix_cap msix; }; void pci__init(void); diff --git a/tools/kvm/virtio/rng.c b/tools/kvm/virtio/rng.c index 1a7f569..5f29ded 100644 --- a/tools/kvm/virtio/rng.c +++ b/tools/kvm/virtio/rng.c @@ -39,6 +39,8 @@ struct rng_dev { u8 isr; u16 config_vector; int fd; + u32 vq_vector[NUM_VIRT_QUEUES]; + u32 msix_io_block; /* virtio queue */ u16 queue_selector; @@ -81,6 +83,9 @@ static bool virtio_rng_pci_io_in(struct ioport *ioport, struct kvm *kvm, u16 por case VIRTIO_MSI_CONFIG_VECTOR: ioport__write16(data, rdev->config_vector); break; + case VIRTIO_MSI_QUEUE_VECTOR: + ioport__write16(data, rdev->vq_vector[rdev->queue_selector]); + break; default: ret = false; break; @@ -109,10 +114,10 @@ static void virtio_rng_do_io(struct kvm *kvm, void *param) struct virt_queue *vq = job->vq; struct rng_dev *rdev = job->rdev; - while (virt_queue__available(vq)) { + while (virt_queue__available(vq)) virtio_rng_do_io_request(kvm, rdev, vq); - virt_queue__trigger_irq(vq, rdev->pci_hdr.irq_line, &rdev->isr, kvm); - } + + kvm__irq_line(kvm, rdev->pci_hdr.irq_line, VIRTIO_IRQ_HIGH); } static bool virtio_rng_pci_io_out(struct ioport *ioport, struct kvm *kvm, u16 port, void *data, int size, u32 count) @@ -125,7 +130,6 @@ static bool virtio_rng_pci_io_out(struct ioport *ioport, struct kvm *kvm, u16 po offset = port - rdev->base_addr; switch (offset) { - case VIRTIO_MSI_QUEUE_VECTOR: case VIRTIO_PCI_GUEST_FEATURES: break; case VIRTIO_PCI_QUEUE_PFN: { @@ -163,8 +167,21 @@ static bool virtio_rng_pci_io_out(struct ioport *ioport, struct kvm *kvm, u16 po rdev->status = ioport__read8(data); break; case VIRTIO_MSI_CONFIG_VECTOR: - rdev->config_vector = VIRTIO_MSI_NO_VECTOR; + rdev->config_vector = ioport__read16(data); + break; + case VIRTIO_MSI_QUEUE_VECTOR: { + u32 gsi; + u32 vec; + + vec = rdev->vq_vector[rdev->queue_selector] = ioport__read16(data); + + gsi = irq__add_msix_route(kvm, + rdev->pci_hdr.msix.table[vec].low, + rdev->pci_hdr.msix.table[vec].high, + rdev->pci_hdr.msix.table[vec].data); + rdev->pci_hdr.irq_line = gsi; break; + } default: ret = false; break; @@ -185,6 +202,16 @@ static void ioevent_callback(struct kvm *kvm, void *param) thread_pool__do_job(&job->job_id); } +static void callback_mmio(u64 addr, u8 *data, u32 len, u8 is_write, void *ptr) +{ + struct rng_dev *rdev = ptr; + void *table = &rdev->pci_hdr.msix.table; + if (is_write) + memcpy(table + addr - rdev->msix_io_block, data, len); + else + memcpy(data, table + addr - rdev->msix_io_block, len); +} + void virtio_rng__init(struct kvm *kvm) { u8 pin, line, dev, i; @@ -196,7 +223,10 @@ void virtio_rng__init(struct kvm *kvm) if (rdev == NULL) return; + rdev->msix_io_block = pci_get_io_space_block(); + rdev_base_addr = ioport__register(IOPORT_EMPTY, &virtio_rng_io_ops, IOPORT_SIZE, rdev); + kvm__register_mmio(kvm, rdev->msix_io_block, 0x100, callback_mmio, rdev); rdev->pci_hdr = (struct pci_device_header) { .vendor_id = PCI_VENDOR_ID_REDHAT_QUMRANET, @@ -207,8 +237,21 @@ void virtio_rng__init(struct kvm *kvm) .subsys_vendor_id = PCI_SUBSYSTEM_VENDOR_ID_REDHAT_QUMRANET, .subsys_id = VIRTIO_ID_RNG, .bar[0] = rdev_base_addr | PCI_BASE_ADDRESS_SPACE_IO, + .bar[1] = rdev->msix_io_block | + PCI_BASE_ADDRESS_SPACE_MEMORY | + PCI_BASE_ADDRESS_MEM_TYPE_64, + /* bar[2] is the continuation of bar[1] for 64bit addressing */ + .bar[2] = 0, + .status = PCI_STATUS_CAP_LIST, + .capabilities = (void *)&rdev->pci_hdr.msix - (void *)&rdev->pci_hdr, }; + rdev->pci_hdr.msix.cap = PCI_CAP_ID_MSIX; + rdev->pci_hdr.msix.next = 0; + rdev->pci_hdr.msix.table_size = (NUM_VIRT_QUEUES + 1) | PCI_MSIX_FLAGS_ENABLE; + rdev->pci_hdr.msix.table_offset = 1; /* Use BAR 1 */ + + rdev->config_vector = 0; rdev->base_addr = rdev_base_addr; rdev->fd = open("/dev/urandom", O_RDONLY); if (rdev->fd < 0) -- 1.7.6 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
