We don't *remove* the old ones, unless VIRTIO_PCI_NO_LEGACY is defined, but they get a friendly #warning about the change.
Note that config option is not prompted; we always enable it for now. Signed-off-by: Rusty Russell <[email protected]> --- drivers/virtio/Kconfig | 12 + drivers/virtio/Makefile | 2 +- drivers/virtio/virtio_pci.c | 858 ------------------------------------ drivers/virtio/virtio_pci_legacy.c | 858 ++++++++++++++++++++++++++++++++++++ include/uapi/linux/virtio_pci.h | 61 ++- 5 files changed, 911 insertions(+), 880 deletions(-) delete mode 100644 drivers/virtio/virtio_pci.c create mode 100644 drivers/virtio/virtio_pci_legacy.c diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig index c6683f2..65de1b2 100644 --- a/drivers/virtio/Kconfig +++ b/drivers/virtio/Kconfig @@ -22,6 +22,18 @@ config VIRTIO_PCI If unsure, say M. +config VIRTIO_PCI_LEGACY + bool + default y + depends on VIRTIO_PCI + ---help--- + The old BAR0 virtio pci layout was deprecated early 2013. + + So look out into your driveway. Do you have a flying car? If + so, you can happily disable this option and virtio will not + break. Otherwise, leave it set. Unless you're testing what + life will be like in The Future. + config VIRTIO_BALLOON tristate "Virtio balloon driver" depends on VIRTIO diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile index 9076635..23834f5 100644 --- a/drivers/virtio/Makefile +++ b/drivers/virtio/Makefile @@ -1,4 +1,4 @@ obj-$(CONFIG_VIRTIO) += virtio.o virtio_ring.o obj-$(CONFIG_VIRTIO_MMIO) += virtio_mmio.o -obj-$(CONFIG_VIRTIO_PCI) += virtio_pci.o +obj-$(CONFIG_VIRTIO_PCI_LEGACY) += virtio_pci_legacy.o obj-$(CONFIG_VIRTIO_BALLOON) += virtio_balloon.o diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c deleted file mode 100644 index 8d081ea..0000000 --- a/drivers/virtio/virtio_pci.c +++ /dev/null @@ -1,858 +0,0 @@ -/* - * Virtio PCI driver - * - * This module allows virtio devices to be used over a virtual PCI device. - * This can be used with QEMU based VMMs like KVM or Xen. - * - * Copyright IBM Corp. 2007 - * - * Authors: - * Anthony Liguori <[email protected]> - * - * This work is licensed under the terms of the GNU GPL, version 2 or later. - * See the COPYING file in the top-level directory. - * - */ - -#include <linux/module.h> -#include <linux/list.h> -#include <linux/pci.h> -#include <linux/slab.h> -#include <linux/interrupt.h> -#include <linux/virtio.h> -#include <linux/virtio_config.h> -#include <linux/virtio_ring.h> -#include <linux/virtio_pci.h> -#include <linux/highmem.h> -#include <linux/spinlock.h> - -MODULE_AUTHOR("Anthony Liguori <[email protected]>"); -MODULE_DESCRIPTION("virtio-pci"); -MODULE_LICENSE("GPL"); -MODULE_VERSION("1"); - -/* Our device structure */ -struct virtio_pci_device -{ - struct virtio_device vdev; - struct pci_dev *pci_dev; - - /* the IO mapping for the PCI config space */ - void __iomem *ioaddr; - - /* a list of queues so we can dispatch IRQs */ - spinlock_t lock; - struct list_head virtqueues; - - /* MSI-X support */ - int msix_enabled; - int intx_enabled; - struct msix_entry *msix_entries; - cpumask_var_t *msix_affinity_masks; - /* Name strings for interrupts. This size should be enough, - * and I'm too lazy to allocate each name separately. */ - char (*msix_names)[256]; - /* Number of available vectors */ - unsigned msix_vectors; - /* Vectors allocated, excluding per-vq vectors if any */ - unsigned msix_used_vectors; - - /* Status saved during hibernate/restore */ - u8 saved_status; - - /* Whether we have vector per vq */ - bool per_vq_vectors; -}; - -/* Constants for MSI-X */ -/* Use first vector for configuration changes, second and the rest for - * virtqueues Thus, we need at least 2 vectors for MSI. */ -enum { - VP_MSIX_CONFIG_VECTOR = 0, - VP_MSIX_VQ_VECTOR = 1, -}; - -struct virtio_pci_vq_info -{ - /* the actual virtqueue */ - struct virtqueue *vq; - - /* the number of entries in the queue */ - int num; - - /* the virtual address of the ring queue */ - void *queue; - - /* the list node for the virtqueues list */ - struct list_head node; - - /* MSI-X vector (or none) */ - unsigned msix_vector; -}; - -/* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */ -static DEFINE_PCI_DEVICE_TABLE(virtio_pci_id_table) = { - { PCI_DEVICE(0x1af4, PCI_ANY_ID) }, - { 0 } -}; - -MODULE_DEVICE_TABLE(pci, virtio_pci_id_table); - -/* Convert a generic virtio device to our structure */ -static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev) -{ - return container_of(vdev, struct virtio_pci_device, vdev); -} - -/* virtio config->get_features() implementation */ -static u64 vp_get_features(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - - /* We only support 32 feature bits. */ - return ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES); -} - -/* virtio config->finalize_features() implementation */ -static void vp_finalize_features(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - - /* Give virtio_ring a chance to accept features. */ - vring_transport_features(vdev); - - /* We only support 32 feature bits. */ - iowrite32(vdev->features, vp_dev->ioaddr+VIRTIO_PCI_GUEST_FEATURES); -} - -/* Device config access: we use guest endian, as per spec. */ -static void vp_get(struct virtio_device *vdev, unsigned offset, - void *buf, unsigned len) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - void __iomem *ioaddr = vp_dev->ioaddr + - VIRTIO_PCI_CONFIG(vp_dev) + offset; - u8 *ptr = buf; - int i; - - for (i = 0; i < len; i++) - ptr[i] = ioread8(ioaddr + i); -} - -#define VP_GETx(bits) \ -static u##bits vp_get##bits(struct virtio_device *vdev, unsigned int offset) \ -{ \ - u##bits v; \ - vp_get(vdev, offset, &v, sizeof(v)); \ - return v; \ -} - -VP_GETx(8) -VP_GETx(16) -VP_GETx(32) -VP_GETx(64) - -static void vp_set(struct virtio_device *vdev, unsigned offset, - const void *buf, unsigned len) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - void __iomem *ioaddr = vp_dev->ioaddr + - VIRTIO_PCI_CONFIG(vp_dev) + offset; - const u8 *ptr = buf; - int i; - - for (i = 0; i < len; i++) - iowrite8(ptr[i], ioaddr + i); -} - -#define VP_SETx(bits) \ -static void vp_set##bits(struct virtio_device *vdev, unsigned int offset, \ - u##bits v) \ -{ \ - vp_set(vdev, offset, &v, sizeof(v)); \ -} - -VP_SETx(8) -VP_SETx(16) -VP_SETx(32) -VP_SETx(64) - -/* config->{get,set}_status() implementations */ -static u8 vp_get_status(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - return ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS); -} - -static void vp_set_status(struct virtio_device *vdev, u8 status) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - /* We should never be setting status to 0. */ - BUG_ON(status == 0); - iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS); -} - -/* wait for pending irq handlers */ -static void vp_synchronize_vectors(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - int i; - - if (vp_dev->intx_enabled) - synchronize_irq(vp_dev->pci_dev->irq); - - for (i = 0; i < vp_dev->msix_vectors; ++i) - synchronize_irq(vp_dev->msix_entries[i].vector); -} - -static void vp_reset(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - /* 0 status means a reset. */ - iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS); - /* Flush out the status write, and flush in device writes, - * including MSi-X interrupts, if any. */ - ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS); - /* Flush pending VQ/configuration callbacks. */ - vp_synchronize_vectors(vdev); -} - -/* the notify function used when creating a virt queue */ -static void vp_notify(struct virtqueue *vq) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); - - /* we write the queue's selector into the notification register to - * signal the other end */ - iowrite16(vq->index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY); -} - -/* Handle a configuration change: Tell driver if it wants to know. */ -static irqreturn_t vp_config_changed(int irq, void *opaque) -{ - struct virtio_pci_device *vp_dev = opaque; - struct virtio_driver *drv; - drv = container_of(vp_dev->vdev.dev.driver, - struct virtio_driver, driver); - - if (drv && drv->config_changed) - drv->config_changed(&vp_dev->vdev); - return IRQ_HANDLED; -} - -/* Notify all virtqueues on an interrupt. */ -static irqreturn_t vp_vring_interrupt(int irq, void *opaque) -{ - struct virtio_pci_device *vp_dev = opaque; - struct virtio_pci_vq_info *info; - irqreturn_t ret = IRQ_NONE; - unsigned long flags; - - spin_lock_irqsave(&vp_dev->lock, flags); - list_for_each_entry(info, &vp_dev->virtqueues, node) { - if (vring_interrupt(irq, info->vq) == IRQ_HANDLED) - ret = IRQ_HANDLED; - } - spin_unlock_irqrestore(&vp_dev->lock, flags); - - return ret; -} - -/* A small wrapper to also acknowledge the interrupt when it's handled. - * I really need an EIO hook for the vring so I can ack the interrupt once we - * know that we'll be handling the IRQ but before we invoke the callback since - * the callback may notify the host which results in the host attempting to - * raise an interrupt that we would then mask once we acknowledged the - * interrupt. */ -static irqreturn_t vp_interrupt(int irq, void *opaque) -{ - struct virtio_pci_device *vp_dev = opaque; - u8 isr; - - /* reading the ISR has the effect of also clearing it so it's very - * important to save off the value. */ - isr = ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR); - - /* It's definitely not us if the ISR was not high */ - if (!isr) - return IRQ_NONE; - - /* Configuration change? Tell driver if it wants to know. */ - if (isr & VIRTIO_PCI_ISR_CONFIG) - vp_config_changed(irq, opaque); - - return vp_vring_interrupt(irq, opaque); -} - -static void vp_free_vectors(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - int i; - - if (vp_dev->intx_enabled) { - free_irq(vp_dev->pci_dev->irq, vp_dev); - vp_dev->intx_enabled = 0; - } - - for (i = 0; i < vp_dev->msix_used_vectors; ++i) - free_irq(vp_dev->msix_entries[i].vector, vp_dev); - - for (i = 0; i < vp_dev->msix_vectors; i++) - if (vp_dev->msix_affinity_masks[i]) - free_cpumask_var(vp_dev->msix_affinity_masks[i]); - - if (vp_dev->msix_enabled) { - /* Disable the vector used for configuration */ - iowrite16(VIRTIO_MSI_NO_VECTOR, - vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); - /* Flush the write out to device */ - ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); - - pci_disable_msix(vp_dev->pci_dev); - vp_dev->msix_enabled = 0; - vp_dev->msix_vectors = 0; - } - - vp_dev->msix_used_vectors = 0; - kfree(vp_dev->msix_names); - vp_dev->msix_names = NULL; - kfree(vp_dev->msix_entries); - vp_dev->msix_entries = NULL; - kfree(vp_dev->msix_affinity_masks); - vp_dev->msix_affinity_masks = NULL; -} - -static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors, - bool per_vq_vectors) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - const char *name = dev_name(&vp_dev->vdev.dev); - unsigned i, v; - int err = -ENOMEM; - - vp_dev->msix_entries = kmalloc(nvectors * sizeof *vp_dev->msix_entries, - GFP_KERNEL); - if (!vp_dev->msix_entries) - goto error; - vp_dev->msix_names = kmalloc(nvectors * sizeof *vp_dev->msix_names, - GFP_KERNEL); - if (!vp_dev->msix_names) - goto error; - vp_dev->msix_affinity_masks - = kzalloc(nvectors * sizeof *vp_dev->msix_affinity_masks, - GFP_KERNEL); - if (!vp_dev->msix_affinity_masks) - goto error; - for (i = 0; i < nvectors; ++i) - if (!alloc_cpumask_var(&vp_dev->msix_affinity_masks[i], - GFP_KERNEL)) - goto error; - - for (i = 0; i < nvectors; ++i) - vp_dev->msix_entries[i].entry = i; - - /* pci_enable_msix returns positive if we can't get this many. */ - err = pci_enable_msix(vp_dev->pci_dev, vp_dev->msix_entries, nvectors); - if (err > 0) - err = -ENOSPC; - if (err) - goto error; - vp_dev->msix_vectors = nvectors; - vp_dev->msix_enabled = 1; - - /* Set the vector used for configuration */ - v = vp_dev->msix_used_vectors; - snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names, - "%s-config", name); - err = request_irq(vp_dev->msix_entries[v].vector, - vp_config_changed, 0, vp_dev->msix_names[v], - vp_dev); - if (err) - goto error; - ++vp_dev->msix_used_vectors; - - iowrite16(v, vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); - /* Verify we had enough resources to assign the vector */ - v = ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); - if (v == VIRTIO_MSI_NO_VECTOR) { - err = -EBUSY; - goto error; - } - - if (!per_vq_vectors) { - /* Shared vector for all VQs */ - v = vp_dev->msix_used_vectors; - snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names, - "%s-virtqueues", name); - err = request_irq(vp_dev->msix_entries[v].vector, - vp_vring_interrupt, 0, vp_dev->msix_names[v], - vp_dev); - if (err) - goto error; - ++vp_dev->msix_used_vectors; - } - return 0; -error: - vp_free_vectors(vdev); - return err; -} - -static int vp_request_intx(struct virtio_device *vdev) -{ - int err; - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - - err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, - IRQF_SHARED, dev_name(&vdev->dev), vp_dev); - if (!err) - vp_dev->intx_enabled = 1; - return err; -} - -static struct virtqueue *setup_vq(struct virtio_device *vdev, unsigned index, - void (*callback)(struct virtqueue *vq), - const char *name, - u16 msix_vec) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - struct virtio_pci_vq_info *info; - struct virtqueue *vq; - unsigned long flags, size; - u16 num; - int err; - - /* Select the queue we're interested in */ - iowrite16(index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL); - - /* Check if queue is either not available or already active. */ - num = ioread16(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NUM); - if (!num || ioread32(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN)) - return ERR_PTR(-ENOENT); - - /* allocate and fill out our structure the represents an active - * queue */ - info = kmalloc(sizeof(struct virtio_pci_vq_info), GFP_KERNEL); - if (!info) - return ERR_PTR(-ENOMEM); - - info->num = num; - info->msix_vector = msix_vec; - - size = PAGE_ALIGN(vring_size(num, VIRTIO_PCI_VRING_ALIGN)); - info->queue = alloc_pages_exact(size, GFP_KERNEL|__GFP_ZERO); - if (info->queue == NULL) { - err = -ENOMEM; - goto out_info; - } - - /* activate the queue */ - iowrite32(virt_to_phys(info->queue) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT, - vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); - - /* create the vring */ - vq = vring_new_virtqueue(index, info->num, VIRTIO_PCI_VRING_ALIGN, vdev, - true, info->queue, vp_notify, callback, name); - if (!vq) { - err = -ENOMEM; - goto out_activate_queue; - } - - vq->priv = info; - info->vq = vq; - - if (msix_vec != VIRTIO_MSI_NO_VECTOR) { - iowrite16(msix_vec, vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR); - msix_vec = ioread16(vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR); - if (msix_vec == VIRTIO_MSI_NO_VECTOR) { - err = -EBUSY; - goto out_assign; - } - } - - if (callback) { - spin_lock_irqsave(&vp_dev->lock, flags); - list_add(&info->node, &vp_dev->virtqueues); - spin_unlock_irqrestore(&vp_dev->lock, flags); - } else { - INIT_LIST_HEAD(&info->node); - } - - return vq; - -out_assign: - vring_del_virtqueue(vq); -out_activate_queue: - iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); - free_pages_exact(info->queue, size); -out_info: - kfree(info); - return ERR_PTR(err); -} - -static void vp_del_vq(struct virtqueue *vq) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); - struct virtio_pci_vq_info *info = vq->priv; - unsigned long flags, size; - - spin_lock_irqsave(&vp_dev->lock, flags); - list_del(&info->node); - spin_unlock_irqrestore(&vp_dev->lock, flags); - - iowrite16(vq->index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL); - - if (vp_dev->msix_enabled) { - iowrite16(VIRTIO_MSI_NO_VECTOR, - vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR); - /* Flush the write out to device */ - ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR); - } - - vring_del_virtqueue(vq); - - /* Select and deactivate the queue */ - iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); - - size = PAGE_ALIGN(vring_size(info->num, VIRTIO_PCI_VRING_ALIGN)); - free_pages_exact(info->queue, size); - kfree(info); -} - -/* the config->del_vqs() implementation */ -static void vp_del_vqs(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - struct virtqueue *vq, *n; - struct virtio_pci_vq_info *info; - - list_for_each_entry_safe(vq, n, &vdev->vqs, list) { - info = vq->priv; - if (vp_dev->per_vq_vectors && - info->msix_vector != VIRTIO_MSI_NO_VECTOR) - free_irq(vp_dev->msix_entries[info->msix_vector].vector, - vq); - vp_del_vq(vq); - } - vp_dev->per_vq_vectors = false; - - vp_free_vectors(vdev); -} - -static int vp_try_to_find_vqs(struct virtio_device *vdev, unsigned nvqs, - struct virtqueue *vqs[], - vq_callback_t *callbacks[], - const char *names[], - bool use_msix, - bool per_vq_vectors) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - u16 msix_vec; - int i, err, nvectors, allocated_vectors; - - if (!use_msix) { - /* Old style: one normal interrupt for change and all vqs. */ - err = vp_request_intx(vdev); - if (err) - goto error_request; - } else { - if (per_vq_vectors) { - /* Best option: one for change interrupt, one per vq. */ - nvectors = 1; - for (i = 0; i < nvqs; ++i) - if (callbacks[i]) - ++nvectors; - } else { - /* Second best: one for change, shared for all vqs. */ - nvectors = 2; - } - - err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors); - if (err) - goto error_request; - } - - vp_dev->per_vq_vectors = per_vq_vectors; - allocated_vectors = vp_dev->msix_used_vectors; - for (i = 0; i < nvqs; ++i) { - if (!names[i]) { - vqs[i] = NULL; - continue; - } else if (!callbacks[i] || !vp_dev->msix_enabled) - msix_vec = VIRTIO_MSI_NO_VECTOR; - else if (vp_dev->per_vq_vectors) - msix_vec = allocated_vectors++; - else - msix_vec = VP_MSIX_VQ_VECTOR; - vqs[i] = setup_vq(vdev, i, callbacks[i], names[i], msix_vec); - if (IS_ERR(vqs[i])) { - err = PTR_ERR(vqs[i]); - goto error_find; - } - - if (!vp_dev->per_vq_vectors || msix_vec == VIRTIO_MSI_NO_VECTOR) - continue; - - /* allocate per-vq irq if available and necessary */ - snprintf(vp_dev->msix_names[msix_vec], - sizeof *vp_dev->msix_names, - "%s-%s", - dev_name(&vp_dev->vdev.dev), names[i]); - err = request_irq(vp_dev->msix_entries[msix_vec].vector, - vring_interrupt, 0, - vp_dev->msix_names[msix_vec], - vqs[i]); - if (err) { - vp_del_vq(vqs[i]); - goto error_find; - } - } - return 0; - -error_find: - vp_del_vqs(vdev); - -error_request: - return err; -} - -/* the config->find_vqs() implementation */ -static int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs, - struct virtqueue *vqs[], - vq_callback_t *callbacks[], - const char *names[]) -{ - int err; - - /* Try MSI-X with one vector per queue. */ - err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, true, true); - if (!err) - return 0; - /* Fallback: MSI-X with one vector for config, one shared for queues. */ - err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, - true, false); - if (!err) - return 0; - /* Finally fall back to regular interrupts. */ - return vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, - false, false); -} - -static const char *vp_bus_name(struct virtio_device *vdev) -{ - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - - return pci_name(vp_dev->pci_dev); -} - -/* Setup the affinity for a virtqueue: - * - force the affinity for per vq vector - * - OR over all affinities for shared MSI - * - ignore the affinity request if we're using INTX - */ -static int vp_set_vq_affinity(struct virtqueue *vq, int cpu) -{ - struct virtio_device *vdev = vq->vdev; - struct virtio_pci_device *vp_dev = to_vp_device(vdev); - struct virtio_pci_vq_info *info = vq->priv; - struct cpumask *mask; - unsigned int irq; - - if (!vq->callback) - return -EINVAL; - - if (vp_dev->msix_enabled) { - mask = vp_dev->msix_affinity_masks[info->msix_vector]; - irq = vp_dev->msix_entries[info->msix_vector].vector; - if (cpu == -1) - irq_set_affinity_hint(irq, NULL); - else { - cpumask_set_cpu(cpu, mask); - irq_set_affinity_hint(irq, mask); - } - } - return 0; -} - -static const struct virtio_config_ops virtio_pci_config_ops = { - .get8 = vp_get8, - .set8 = vp_set8, - .get16 = vp_get16, - .set16 = vp_set16, - .get32 = vp_get32, - .set32 = vp_set32, - .get64 = vp_get64, - .set64 = vp_set64, - .get_status = vp_get_status, - .set_status = vp_set_status, - .reset = vp_reset, - .find_vqs = vp_find_vqs, - .del_vqs = vp_del_vqs, - .get_features = vp_get_features, - .finalize_features = vp_finalize_features, - .bus_name = vp_bus_name, - .set_vq_affinity = vp_set_vq_affinity, -}; - -static void virtio_pci_release_dev(struct device *_d) -{ - /* - * No need for a release method as we allocate/free - * all devices together with the pci devices. - * Provide an empty one to avoid getting a warning from core. - */ -} - -/* the PCI probing function */ -static int virtio_pci_probe(struct pci_dev *pci_dev, - const struct pci_device_id *id) -{ - struct virtio_pci_device *vp_dev; - int err; - - /* We only own devices >= 0x1000 and <= 0x103f: leave the rest. */ - if (pci_dev->device < 0x1000 || pci_dev->device > 0x103f) - return -ENODEV; - - if (pci_dev->revision != VIRTIO_PCI_ABI_VERSION) { - printk(KERN_ERR "virtio_pci: expected ABI version %d, got %d\n", - VIRTIO_PCI_ABI_VERSION, pci_dev->revision); - return -ENODEV; - } - - /* allocate our structure and fill it out */ - vp_dev = kzalloc(sizeof(struct virtio_pci_device), GFP_KERNEL); - if (vp_dev == NULL) - return -ENOMEM; - - vp_dev->vdev.dev.parent = &pci_dev->dev; - vp_dev->vdev.dev.release = virtio_pci_release_dev; - vp_dev->vdev.config = &virtio_pci_config_ops; - vp_dev->pci_dev = pci_dev; - INIT_LIST_HEAD(&vp_dev->virtqueues); - spin_lock_init(&vp_dev->lock); - - /* Disable MSI/MSIX to bring device to a known good state. */ - pci_msi_off(pci_dev); - - /* enable the device */ - err = pci_enable_device(pci_dev); - if (err) - goto out; - - err = pci_request_regions(pci_dev, "virtio-pci"); - if (err) - goto out_enable_device; - - vp_dev->ioaddr = pci_iomap(pci_dev, 0, 0); - if (vp_dev->ioaddr == NULL) { - err = -ENOMEM; - goto out_req_regions; - } - - pci_set_drvdata(pci_dev, vp_dev); - pci_set_master(pci_dev); - - /* we use the subsystem vendor/device id as the virtio vendor/device - * id. this allows us to use the same PCI vendor/device id for all - * virtio devices and to identify the particular virtio driver by - * the subsystem ids */ - vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor; - vp_dev->vdev.id.device = pci_dev->subsystem_device; - - /* finally register the virtio device */ - err = register_virtio_device(&vp_dev->vdev); - if (err) - goto out_set_drvdata; - - return 0; - -out_set_drvdata: - pci_set_drvdata(pci_dev, NULL); - pci_iounmap(pci_dev, vp_dev->ioaddr); -out_req_regions: - pci_release_regions(pci_dev); -out_enable_device: - pci_disable_device(pci_dev); -out: - kfree(vp_dev); - return err; -} - -static void virtio_pci_remove(struct pci_dev *pci_dev) -{ - struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); - - unregister_virtio_device(&vp_dev->vdev); - - vp_del_vqs(&vp_dev->vdev); - pci_set_drvdata(pci_dev, NULL); - pci_iounmap(pci_dev, vp_dev->ioaddr); - pci_release_regions(pci_dev); - pci_disable_device(pci_dev); - kfree(vp_dev); -} - -#ifdef CONFIG_PM -static int virtio_pci_freeze(struct device *dev) -{ - struct pci_dev *pci_dev = to_pci_dev(dev); - struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); - struct virtio_driver *drv; - int ret; - - drv = container_of(vp_dev->vdev.dev.driver, - struct virtio_driver, driver); - - ret = 0; - vp_dev->saved_status = vp_get_status(&vp_dev->vdev); - if (drv && drv->freeze) - ret = drv->freeze(&vp_dev->vdev); - - if (!ret) - pci_disable_device(pci_dev); - return ret; -} - -static int virtio_pci_restore(struct device *dev) -{ - struct pci_dev *pci_dev = to_pci_dev(dev); - struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); - struct virtio_driver *drv; - int ret; - - drv = container_of(vp_dev->vdev.dev.driver, - struct virtio_driver, driver); - - ret = pci_enable_device(pci_dev); - if (ret) - return ret; - - pci_set_master(pci_dev); - vp_finalize_features(&vp_dev->vdev); - - if (drv && drv->restore) - ret = drv->restore(&vp_dev->vdev); - - /* Finally, tell the device we're all set */ - if (!ret) - vp_set_status(&vp_dev->vdev, vp_dev->saved_status); - - return ret; -} - -static const struct dev_pm_ops virtio_pci_pm_ops = { - SET_SYSTEM_SLEEP_PM_OPS(virtio_pci_freeze, virtio_pci_restore) -}; -#endif - -static struct pci_driver virtio_pci_driver = { - .name = "virtio-pci", - .id_table = virtio_pci_id_table, - .probe = virtio_pci_probe, - .remove = virtio_pci_remove, -#ifdef CONFIG_PM - .driver.pm = &virtio_pci_pm_ops, -#endif -}; - -module_pci_driver(virtio_pci_driver); diff --git a/drivers/virtio/virtio_pci_legacy.c b/drivers/virtio/virtio_pci_legacy.c new file mode 100644 index 0000000..77baa7c --- /dev/null +++ b/drivers/virtio/virtio_pci_legacy.c @@ -0,0 +1,858 @@ +/* + * Virtio PCI driver (legacy mode) + * + * This module allows virtio devices to be used over a virtual PCI device. + * This can be used with QEMU based VMMs like KVM or Xen. + * + * Copyright IBM Corp. 2007 + * + * Authors: + * Anthony Liguori <[email protected]> + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + * + */ + +#include <linux/module.h> +#include <linux/list.h> +#include <linux/pci.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/virtio.h> +#include <linux/virtio_config.h> +#include <linux/virtio_ring.h> +#include <linux/virtio_pci.h> +#include <linux/highmem.h> +#include <linux/spinlock.h> + +MODULE_AUTHOR("Anthony Liguori <[email protected]>"); +MODULE_DESCRIPTION("virtio-pci-legacy"); +MODULE_LICENSE("GPL"); +MODULE_VERSION("1"); + +/* Our device structure */ +struct virtio_pci_device +{ + struct virtio_device vdev; + struct pci_dev *pci_dev; + + /* the IO mapping for the PCI config space */ + void __iomem *ioaddr; + + /* a list of queues so we can dispatch IRQs */ + spinlock_t lock; + struct list_head virtqueues; + + /* MSI-X support */ + int msix_enabled; + int intx_enabled; + struct msix_entry *msix_entries; + cpumask_var_t *msix_affinity_masks; + /* Name strings for interrupts. This size should be enough, + * and I'm too lazy to allocate each name separately. */ + char (*msix_names)[256]; + /* Number of available vectors */ + unsigned msix_vectors; + /* Vectors allocated, excluding per-vq vectors if any */ + unsigned msix_used_vectors; + + /* Status saved during hibernate/restore */ + u8 saved_status; + + /* Whether we have vector per vq */ + bool per_vq_vectors; +}; + +/* Constants for MSI-X */ +/* Use first vector for configuration changes, second and the rest for + * virtqueues Thus, we need at least 2 vectors for MSI. */ +enum { + VP_MSIX_CONFIG_VECTOR = 0, + VP_MSIX_VQ_VECTOR = 1, +}; + +struct virtio_pci_vq_info +{ + /* the actual virtqueue */ + struct virtqueue *vq; + + /* the number of entries in the queue */ + int num; + + /* the virtual address of the ring queue */ + void *queue; + + /* the list node for the virtqueues list */ + struct list_head node; + + /* MSI-X vector (or none) */ + unsigned msix_vector; +}; + +/* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */ +static DEFINE_PCI_DEVICE_TABLE(virtio_pci_id_table) = { + { PCI_DEVICE(0x1af4, PCI_ANY_ID) }, + { 0 } +}; + +MODULE_DEVICE_TABLE(pci, virtio_pci_id_table); + +/* Convert a generic virtio device to our structure */ +static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev) +{ + return container_of(vdev, struct virtio_pci_device, vdev); +} + +/* virtio config->get_features() implementation */ +static u64 vp_get_features(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + /* We only support 32 feature bits. */ + return ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES); +} + +/* virtio config->finalize_features() implementation */ +static void vp_finalize_features(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + /* Give virtio_ring a chance to accept features. */ + vring_transport_features(vdev); + + /* We only support 32 feature bits. */ + iowrite32(vdev->features, vp_dev->ioaddr+VIRTIO_PCI_GUEST_FEATURES); +} + +/* Device config access: we use guest endian, as per spec. */ +static void vp_get(struct virtio_device *vdev, unsigned offset, + void *buf, unsigned len) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + void __iomem *ioaddr = vp_dev->ioaddr + + VIRTIO_PCI_CONFIG(vp_dev) + offset; + u8 *ptr = buf; + int i; + + for (i = 0; i < len; i++) + ptr[i] = ioread8(ioaddr + i); +} + +#define VP_GETx(bits) \ +static u##bits vp_get##bits(struct virtio_device *vdev, unsigned int offset) \ +{ \ + u##bits v; \ + vp_get(vdev, offset, &v, sizeof(v)); \ + return v; \ +} + +VP_GETx(8) +VP_GETx(16) +VP_GETx(32) +VP_GETx(64) + +static void vp_set(struct virtio_device *vdev, unsigned offset, + const void *buf, unsigned len) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + void __iomem *ioaddr = vp_dev->ioaddr + + VIRTIO_PCI_CONFIG(vp_dev) + offset; + const u8 *ptr = buf; + int i; + + for (i = 0; i < len; i++) + iowrite8(ptr[i], ioaddr + i); +} + +#define VP_SETx(bits) \ +static void vp_set##bits(struct virtio_device *vdev, unsigned int offset, \ + u##bits v) \ +{ \ + vp_set(vdev, offset, &v, sizeof(v)); \ +} + +VP_SETx(8) +VP_SETx(16) +VP_SETx(32) +VP_SETx(64) + +/* config->{get,set}_status() implementations */ +static u8 vp_get_status(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + return ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS); +} + +static void vp_set_status(struct virtio_device *vdev, u8 status) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + /* We should never be setting status to 0. */ + BUG_ON(status == 0); + iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS); +} + +/* wait for pending irq handlers */ +static void vp_synchronize_vectors(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + int i; + + if (vp_dev->intx_enabled) + synchronize_irq(vp_dev->pci_dev->irq); + + for (i = 0; i < vp_dev->msix_vectors; ++i) + synchronize_irq(vp_dev->msix_entries[i].vector); +} + +static void vp_reset(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + /* 0 status means a reset. */ + iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS); + /* Flush out the status write, and flush in device writes, + * including MSi-X interrupts, if any. */ + ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS); + /* Flush pending VQ/configuration callbacks. */ + vp_synchronize_vectors(vdev); +} + +/* the notify function used when creating a virt queue */ +static void vp_notify(struct virtqueue *vq) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); + + /* we write the queue's selector into the notification register to + * signal the other end */ + iowrite16(vq->index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY); +} + +/* Handle a configuration change: Tell driver if it wants to know. */ +static irqreturn_t vp_config_changed(int irq, void *opaque) +{ + struct virtio_pci_device *vp_dev = opaque; + struct virtio_driver *drv; + drv = container_of(vp_dev->vdev.dev.driver, + struct virtio_driver, driver); + + if (drv && drv->config_changed) + drv->config_changed(&vp_dev->vdev); + return IRQ_HANDLED; +} + +/* Notify all virtqueues on an interrupt. */ +static irqreturn_t vp_vring_interrupt(int irq, void *opaque) +{ + struct virtio_pci_device *vp_dev = opaque; + struct virtio_pci_vq_info *info; + irqreturn_t ret = IRQ_NONE; + unsigned long flags; + + spin_lock_irqsave(&vp_dev->lock, flags); + list_for_each_entry(info, &vp_dev->virtqueues, node) { + if (vring_interrupt(irq, info->vq) == IRQ_HANDLED) + ret = IRQ_HANDLED; + } + spin_unlock_irqrestore(&vp_dev->lock, flags); + + return ret; +} + +/* A small wrapper to also acknowledge the interrupt when it's handled. + * I really need an EIO hook for the vring so I can ack the interrupt once we + * know that we'll be handling the IRQ but before we invoke the callback since + * the callback may notify the host which results in the host attempting to + * raise an interrupt that we would then mask once we acknowledged the + * interrupt. */ +static irqreturn_t vp_interrupt(int irq, void *opaque) +{ + struct virtio_pci_device *vp_dev = opaque; + u8 isr; + + /* reading the ISR has the effect of also clearing it so it's very + * important to save off the value. */ + isr = ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR); + + /* It's definitely not us if the ISR was not high */ + if (!isr) + return IRQ_NONE; + + /* Configuration change? Tell driver if it wants to know. */ + if (isr & VIRTIO_PCI_ISR_CONFIG) + vp_config_changed(irq, opaque); + + return vp_vring_interrupt(irq, opaque); +} + +static void vp_free_vectors(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + int i; + + if (vp_dev->intx_enabled) { + free_irq(vp_dev->pci_dev->irq, vp_dev); + vp_dev->intx_enabled = 0; + } + + for (i = 0; i < vp_dev->msix_used_vectors; ++i) + free_irq(vp_dev->msix_entries[i].vector, vp_dev); + + for (i = 0; i < vp_dev->msix_vectors; i++) + if (vp_dev->msix_affinity_masks[i]) + free_cpumask_var(vp_dev->msix_affinity_masks[i]); + + if (vp_dev->msix_enabled) { + /* Disable the vector used for configuration */ + iowrite16(VIRTIO_MSI_NO_VECTOR, + vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); + /* Flush the write out to device */ + ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); + + pci_disable_msix(vp_dev->pci_dev); + vp_dev->msix_enabled = 0; + vp_dev->msix_vectors = 0; + } + + vp_dev->msix_used_vectors = 0; + kfree(vp_dev->msix_names); + vp_dev->msix_names = NULL; + kfree(vp_dev->msix_entries); + vp_dev->msix_entries = NULL; + kfree(vp_dev->msix_affinity_masks); + vp_dev->msix_affinity_masks = NULL; +} + +static int vp_request_msix_vectors(struct virtio_device *vdev, int nvectors, + bool per_vq_vectors) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + const char *name = dev_name(&vp_dev->vdev.dev); + unsigned i, v; + int err = -ENOMEM; + + vp_dev->msix_entries = kmalloc(nvectors * sizeof *vp_dev->msix_entries, + GFP_KERNEL); + if (!vp_dev->msix_entries) + goto error; + vp_dev->msix_names = kmalloc(nvectors * sizeof *vp_dev->msix_names, + GFP_KERNEL); + if (!vp_dev->msix_names) + goto error; + vp_dev->msix_affinity_masks + = kzalloc(nvectors * sizeof *vp_dev->msix_affinity_masks, + GFP_KERNEL); + if (!vp_dev->msix_affinity_masks) + goto error; + for (i = 0; i < nvectors; ++i) + if (!alloc_cpumask_var(&vp_dev->msix_affinity_masks[i], + GFP_KERNEL)) + goto error; + + for (i = 0; i < nvectors; ++i) + vp_dev->msix_entries[i].entry = i; + + /* pci_enable_msix returns positive if we can't get this many. */ + err = pci_enable_msix(vp_dev->pci_dev, vp_dev->msix_entries, nvectors); + if (err > 0) + err = -ENOSPC; + if (err) + goto error; + vp_dev->msix_vectors = nvectors; + vp_dev->msix_enabled = 1; + + /* Set the vector used for configuration */ + v = vp_dev->msix_used_vectors; + snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names, + "%s-config", name); + err = request_irq(vp_dev->msix_entries[v].vector, + vp_config_changed, 0, vp_dev->msix_names[v], + vp_dev); + if (err) + goto error; + ++vp_dev->msix_used_vectors; + + iowrite16(v, vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); + /* Verify we had enough resources to assign the vector */ + v = ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); + if (v == VIRTIO_MSI_NO_VECTOR) { + err = -EBUSY; + goto error; + } + + if (!per_vq_vectors) { + /* Shared vector for all VQs */ + v = vp_dev->msix_used_vectors; + snprintf(vp_dev->msix_names[v], sizeof *vp_dev->msix_names, + "%s-virtqueues", name); + err = request_irq(vp_dev->msix_entries[v].vector, + vp_vring_interrupt, 0, vp_dev->msix_names[v], + vp_dev); + if (err) + goto error; + ++vp_dev->msix_used_vectors; + } + return 0; +error: + vp_free_vectors(vdev); + return err; +} + +static int vp_request_intx(struct virtio_device *vdev) +{ + int err; + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, + IRQF_SHARED, dev_name(&vdev->dev), vp_dev); + if (!err) + vp_dev->intx_enabled = 1; + return err; +} + +static struct virtqueue *setup_vq(struct virtio_device *vdev, unsigned index, + void (*callback)(struct virtqueue *vq), + const char *name, + u16 msix_vec) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_pci_vq_info *info; + struct virtqueue *vq; + unsigned long flags, size; + u16 num; + int err; + + /* Select the queue we're interested in */ + iowrite16(index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL); + + /* Check if queue is either not available or already active. */ + num = ioread16(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NUM); + if (!num || ioread32(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN)) + return ERR_PTR(-ENOENT); + + /* allocate and fill out our structure the represents an active + * queue */ + info = kmalloc(sizeof(struct virtio_pci_vq_info), GFP_KERNEL); + if (!info) + return ERR_PTR(-ENOMEM); + + info->num = num; + info->msix_vector = msix_vec; + + size = PAGE_ALIGN(vring_size(num, VIRTIO_PCI_VRING_ALIGN)); + info->queue = alloc_pages_exact(size, GFP_KERNEL|__GFP_ZERO); + if (info->queue == NULL) { + err = -ENOMEM; + goto out_info; + } + + /* activate the queue */ + iowrite32(virt_to_phys(info->queue) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT, + vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); + + /* create the vring */ + vq = vring_new_virtqueue(index, info->num, VIRTIO_PCI_VRING_ALIGN, vdev, + true, info->queue, vp_notify, callback, name); + if (!vq) { + err = -ENOMEM; + goto out_activate_queue; + } + + vq->priv = info; + info->vq = vq; + + if (msix_vec != VIRTIO_MSI_NO_VECTOR) { + iowrite16(msix_vec, vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR); + msix_vec = ioread16(vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR); + if (msix_vec == VIRTIO_MSI_NO_VECTOR) { + err = -EBUSY; + goto out_assign; + } + } + + if (callback) { + spin_lock_irqsave(&vp_dev->lock, flags); + list_add(&info->node, &vp_dev->virtqueues); + spin_unlock_irqrestore(&vp_dev->lock, flags); + } else { + INIT_LIST_HEAD(&info->node); + } + + return vq; + +out_assign: + vring_del_virtqueue(vq); +out_activate_queue: + iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); + free_pages_exact(info->queue, size); +out_info: + kfree(info); + return ERR_PTR(err); +} + +static void vp_del_vq(struct virtqueue *vq) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); + struct virtio_pci_vq_info *info = vq->priv; + unsigned long flags, size; + + spin_lock_irqsave(&vp_dev->lock, flags); + list_del(&info->node); + spin_unlock_irqrestore(&vp_dev->lock, flags); + + iowrite16(vq->index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL); + + if (vp_dev->msix_enabled) { + iowrite16(VIRTIO_MSI_NO_VECTOR, + vp_dev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR); + /* Flush the write out to device */ + ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR); + } + + vring_del_virtqueue(vq); + + /* Select and deactivate the queue */ + iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); + + size = PAGE_ALIGN(vring_size(info->num, VIRTIO_PCI_VRING_ALIGN)); + free_pages_exact(info->queue, size); + kfree(info); +} + +/* the config->del_vqs() implementation */ +static void vp_del_vqs(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtqueue *vq, *n; + struct virtio_pci_vq_info *info; + + list_for_each_entry_safe(vq, n, &vdev->vqs, list) { + info = vq->priv; + if (vp_dev->per_vq_vectors && + info->msix_vector != VIRTIO_MSI_NO_VECTOR) + free_irq(vp_dev->msix_entries[info->msix_vector].vector, + vq); + vp_del_vq(vq); + } + vp_dev->per_vq_vectors = false; + + vp_free_vectors(vdev); +} + +static int vp_try_to_find_vqs(struct virtio_device *vdev, unsigned nvqs, + struct virtqueue *vqs[], + vq_callback_t *callbacks[], + const char *names[], + bool use_msix, + bool per_vq_vectors) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + u16 msix_vec; + int i, err, nvectors, allocated_vectors; + + if (!use_msix) { + /* Old style: one normal interrupt for change and all vqs. */ + err = vp_request_intx(vdev); + if (err) + goto error_request; + } else { + if (per_vq_vectors) { + /* Best option: one for change interrupt, one per vq. */ + nvectors = 1; + for (i = 0; i < nvqs; ++i) + if (callbacks[i]) + ++nvectors; + } else { + /* Second best: one for change, shared for all vqs. */ + nvectors = 2; + } + + err = vp_request_msix_vectors(vdev, nvectors, per_vq_vectors); + if (err) + goto error_request; + } + + vp_dev->per_vq_vectors = per_vq_vectors; + allocated_vectors = vp_dev->msix_used_vectors; + for (i = 0; i < nvqs; ++i) { + if (!names[i]) { + vqs[i] = NULL; + continue; + } else if (!callbacks[i] || !vp_dev->msix_enabled) + msix_vec = VIRTIO_MSI_NO_VECTOR; + else if (vp_dev->per_vq_vectors) + msix_vec = allocated_vectors++; + else + msix_vec = VP_MSIX_VQ_VECTOR; + vqs[i] = setup_vq(vdev, i, callbacks[i], names[i], msix_vec); + if (IS_ERR(vqs[i])) { + err = PTR_ERR(vqs[i]); + goto error_find; + } + + if (!vp_dev->per_vq_vectors || msix_vec == VIRTIO_MSI_NO_VECTOR) + continue; + + /* allocate per-vq irq if available and necessary */ + snprintf(vp_dev->msix_names[msix_vec], + sizeof *vp_dev->msix_names, + "%s-%s", + dev_name(&vp_dev->vdev.dev), names[i]); + err = request_irq(vp_dev->msix_entries[msix_vec].vector, + vring_interrupt, 0, + vp_dev->msix_names[msix_vec], + vqs[i]); + if (err) { + vp_del_vq(vqs[i]); + goto error_find; + } + } + return 0; + +error_find: + vp_del_vqs(vdev); + +error_request: + return err; +} + +/* the config->find_vqs() implementation */ +static int vp_find_vqs(struct virtio_device *vdev, unsigned nvqs, + struct virtqueue *vqs[], + vq_callback_t *callbacks[], + const char *names[]) +{ + int err; + + /* Try MSI-X with one vector per queue. */ + err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, true, true); + if (!err) + return 0; + /* Fallback: MSI-X with one vector for config, one shared for queues. */ + err = vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, + true, false); + if (!err) + return 0; + /* Finally fall back to regular interrupts. */ + return vp_try_to_find_vqs(vdev, nvqs, vqs, callbacks, names, + false, false); +} + +static const char *vp_bus_name(struct virtio_device *vdev) +{ + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + + return pci_name(vp_dev->pci_dev); +} + +/* Setup the affinity for a virtqueue: + * - force the affinity for per vq vector + * - OR over all affinities for shared MSI + * - ignore the affinity request if we're using INTX + */ +static int vp_set_vq_affinity(struct virtqueue *vq, int cpu) +{ + struct virtio_device *vdev = vq->vdev; + struct virtio_pci_device *vp_dev = to_vp_device(vdev); + struct virtio_pci_vq_info *info = vq->priv; + struct cpumask *mask; + unsigned int irq; + + if (!vq->callback) + return -EINVAL; + + if (vp_dev->msix_enabled) { + mask = vp_dev->msix_affinity_masks[info->msix_vector]; + irq = vp_dev->msix_entries[info->msix_vector].vector; + if (cpu == -1) + irq_set_affinity_hint(irq, NULL); + else { + cpumask_set_cpu(cpu, mask); + irq_set_affinity_hint(irq, mask); + } + } + return 0; +} + +static const struct virtio_config_ops virtio_pci_config_ops = { + .get8 = vp_get8, + .set8 = vp_set8, + .get16 = vp_get16, + .set16 = vp_set16, + .get32 = vp_get32, + .set32 = vp_set32, + .get64 = vp_get64, + .set64 = vp_set64, + .get_status = vp_get_status, + .set_status = vp_set_status, + .reset = vp_reset, + .find_vqs = vp_find_vqs, + .del_vqs = vp_del_vqs, + .get_features = vp_get_features, + .finalize_features = vp_finalize_features, + .bus_name = vp_bus_name, + .set_vq_affinity = vp_set_vq_affinity, +}; + +static void virtio_pci_release_dev(struct device *_d) +{ + /* + * No need for a release method as we allocate/free + * all devices together with the pci devices. + * Provide an empty one to avoid getting a warning from core. + */ +} + +/* the PCI probing function */ +static int virtio_pci_probe(struct pci_dev *pci_dev, + const struct pci_device_id *id) +{ + struct virtio_pci_device *vp_dev; + int err; + + /* We only own devices >= 0x1000 and <= 0x103f: leave the rest. */ + if (pci_dev->device < 0x1000 || pci_dev->device > 0x103f) + return -ENODEV; + + if (pci_dev->revision != VIRTIO_PCI_ABI_VERSION) { + printk(KERN_ERR "virtio_pci_legacy: expected ABI version %d, got %d\n", + VIRTIO_PCI_ABI_VERSION, pci_dev->revision); + return -ENODEV; + } + + /* allocate our structure and fill it out */ + vp_dev = kzalloc(sizeof(struct virtio_pci_device), GFP_KERNEL); + if (vp_dev == NULL) + return -ENOMEM; + + vp_dev->vdev.dev.parent = &pci_dev->dev; + vp_dev->vdev.dev.release = virtio_pci_release_dev; + vp_dev->vdev.config = &virtio_pci_config_ops; + vp_dev->pci_dev = pci_dev; + INIT_LIST_HEAD(&vp_dev->virtqueues); + spin_lock_init(&vp_dev->lock); + + /* Disable MSI/MSIX to bring device to a known good state. */ + pci_msi_off(pci_dev); + + /* enable the device */ + err = pci_enable_device(pci_dev); + if (err) + goto out; + + err = pci_request_regions(pci_dev, "virtio-pci-legacy"); + if (err) + goto out_enable_device; + + vp_dev->ioaddr = pci_iomap(pci_dev, 0, 0); + if (vp_dev->ioaddr == NULL) { + err = -ENOMEM; + goto out_req_regions; + } + + pci_set_drvdata(pci_dev, vp_dev); + pci_set_master(pci_dev); + + /* we use the subsystem vendor/device id as the virtio vendor/device + * id. this allows us to use the same PCI vendor/device id for all + * virtio devices and to identify the particular virtio driver by + * the subsystem ids */ + vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor; + vp_dev->vdev.id.device = pci_dev->subsystem_device; + + /* finally register the virtio device */ + err = register_virtio_device(&vp_dev->vdev); + if (err) + goto out_set_drvdata; + + return 0; + +out_set_drvdata: + pci_set_drvdata(pci_dev, NULL); + pci_iounmap(pci_dev, vp_dev->ioaddr); +out_req_regions: + pci_release_regions(pci_dev); +out_enable_device: + pci_disable_device(pci_dev); +out: + kfree(vp_dev); + return err; +} + +static void virtio_pci_remove(struct pci_dev *pci_dev) +{ + struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); + + unregister_virtio_device(&vp_dev->vdev); + + vp_del_vqs(&vp_dev->vdev); + pci_set_drvdata(pci_dev, NULL); + pci_iounmap(pci_dev, vp_dev->ioaddr); + pci_release_regions(pci_dev); + pci_disable_device(pci_dev); + kfree(vp_dev); +} + +#ifdef CONFIG_PM +static int virtio_pci_freeze(struct device *dev) +{ + struct pci_dev *pci_dev = to_pci_dev(dev); + struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); + struct virtio_driver *drv; + int ret; + + drv = container_of(vp_dev->vdev.dev.driver, + struct virtio_driver, driver); + + ret = 0; + vp_dev->saved_status = vp_get_status(&vp_dev->vdev); + if (drv && drv->freeze) + ret = drv->freeze(&vp_dev->vdev); + + if (!ret) + pci_disable_device(pci_dev); + return ret; +} + +static int virtio_pci_restore(struct device *dev) +{ + struct pci_dev *pci_dev = to_pci_dev(dev); + struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); + struct virtio_driver *drv; + int ret; + + drv = container_of(vp_dev->vdev.dev.driver, + struct virtio_driver, driver); + + ret = pci_enable_device(pci_dev); + if (ret) + return ret; + + pci_set_master(pci_dev); + vp_finalize_features(&vp_dev->vdev); + + if (drv && drv->restore) + ret = drv->restore(&vp_dev->vdev); + + /* Finally, tell the device we're all set */ + if (!ret) + vp_set_status(&vp_dev->vdev, vp_dev->saved_status); + + return ret; +} + +static const struct dev_pm_ops virtio_pci_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(virtio_pci_freeze, virtio_pci_restore) +}; +#endif + +static struct pci_driver virtio_pci_driver_legacy = { + .name = "virtio-pci-legacy", + .id_table = virtio_pci_id_table, + .probe = virtio_pci_probe, + .remove = virtio_pci_remove, +#ifdef CONFIG_PM + .driver.pm = &virtio_pci_pm_ops, +#endif +}; + +module_pci_driver(virtio_pci_driver_legacy); diff --git a/include/uapi/linux/virtio_pci.h b/include/uapi/linux/virtio_pci.h index b0e7c91..9eb6373 100644 --- a/include/uapi/linux/virtio_pci.h +++ b/include/uapi/linux/virtio_pci.h @@ -42,56 +42,75 @@ #include <linux/virtio_config.h> /* A 32-bit r/o bitmask of the features supported by the host */ -#define VIRTIO_PCI_HOST_FEATURES 0 +#define VIRTIO_PCI_LEGACY_HOST_FEATURES 0 /* A 32-bit r/w bitmask of features activated by the guest */ -#define VIRTIO_PCI_GUEST_FEATURES 4 +#define VIRTIO_PCI_LEGACY_GUEST_FEATURES 4 /* A 32-bit r/w PFN for the currently selected queue */ -#define VIRTIO_PCI_QUEUE_PFN 8 +#define VIRTIO_PCI_LEGACY_QUEUE_PFN 8 /* A 16-bit r/o queue size for the currently selected queue */ -#define VIRTIO_PCI_QUEUE_NUM 12 +#define VIRTIO_PCI_LEGACY_QUEUE_NUM 12 /* A 16-bit r/w queue selector */ -#define VIRTIO_PCI_QUEUE_SEL 14 +#define VIRTIO_PCI_LEGACY_QUEUE_SEL 14 /* A 16-bit r/w queue notifier */ -#define VIRTIO_PCI_QUEUE_NOTIFY 16 +#define VIRTIO_PCI_LEGACY_QUEUE_NOTIFY 16 /* An 8-bit device status register. */ -#define VIRTIO_PCI_STATUS 18 +#define VIRTIO_PCI_LEGACY_STATUS 18 /* An 8-bit r/o interrupt status register. Reading the value will return the * current contents of the ISR and will also clear it. This is effectively * a read-and-acknowledge. */ -#define VIRTIO_PCI_ISR 19 - -/* The bit of the ISR which indicates a device configuration change. */ -#define VIRTIO_PCI_ISR_CONFIG 0x2 +#define VIRTIO_PCI_LEGACY_ISR 19 /* MSI-X registers: only enabled if MSI-X is enabled. */ /* A 16-bit vector for configuration changes. */ -#define VIRTIO_MSI_CONFIG_VECTOR 20 +#define VIRTIO_MSI_LEGACY_CONFIG_VECTOR 20 /* A 16-bit vector for selected queue notifications. */ -#define VIRTIO_MSI_QUEUE_VECTOR 22 -/* Vector value used to disable MSI for queue */ -#define VIRTIO_MSI_NO_VECTOR 0xffff +#define VIRTIO_MSI_LEGACY_QUEUE_VECTOR 22 /* The remaining space is defined by each driver as the per-driver * configuration space */ -#define VIRTIO_PCI_CONFIG(dev) ((dev)->msix_enabled ? 24 : 20) - -/* Virtio ABI version, this must match exactly */ -#define VIRTIO_PCI_ABI_VERSION 0 +#define VIRTIO_PCI_LEGACY_CONFIG(dev) ((dev)->msix_enabled ? 24 : 20) /* How many bits to shift physical queue address written to QUEUE_PFN. * 12 is historical, and due to x86 page size. */ -#define VIRTIO_PCI_QUEUE_ADDR_SHIFT 12 +#define VIRTIO_PCI_LEGACY_QUEUE_ADDR_SHIFT 12 /* The alignment to use between consumer and producer parts of vring. * x86 pagesize again. */ -#define VIRTIO_PCI_VRING_ALIGN 4096 +#define VIRTIO_PCI_LEGACY_VRING_ALIGN 4096 + +#ifndef VIRTIO_PCI_NO_LEGACY +/* Don't break compile of old userspace code. These will go away. */ +#warning "Please support virtio_pci non-legacy mode!" +#define VIRTIO_PCI_HOST_FEATURES VIRTIO_PCI_LEGACY_HOST_FEATURES +#define VIRTIO_PCI_GUEST_FEATURES VIRTIO_PCI_LEGACY_GUEST_FEATURES +#define VIRTIO_PCI_QUEUE_PFN VIRTIO_PCI_LEGACY_QUEUE_PFN +#define VIRTIO_PCI_QUEUE_NUM VIRTIO_PCI_LEGACY_QUEUE_NUM +#define VIRTIO_PCI_QUEUE_SEL VIRTIO_PCI_LEGACY_QUEUE_SEL +#define VIRTIO_PCI_QUEUE_NOTIFY VIRTIO_PCI_LEGACY_QUEUE_NOTIFY +#define VIRTIO_PCI_STATUS VIRTIO_PCI_LEGACY_STATUS +#define VIRTIO_PCI_ISR VIRTIO_PCI_LEGACY_ISR +#define VIRTIO_MSI_CONFIG_VECTOR VIRTIO_MSI_LEGACY_CONFIG_VECTOR +#define VIRTIO_MSI_QUEUE_VECTOR VIRTIO_MSI_LEGACY_QUEUE_VECTOR +#define VIRTIO_PCI_CONFIG(dev) VIRTIO_PCI_LEGACY_CONFIG(dev) +#define VIRTIO_PCI_QUEUE_ADDR_SHIFT VIRTIO_PCI_LEGACY_QUEUE_ADDR_SHIFT +#define VIRTIO_PCI_VRING_ALIGN VIRTIO_PCI_LEGACY_VRING_ALIGN +#endif /* ...!KERNEL */ + +/* Virtio ABI version, this must match exactly */ +#define VIRTIO_PCI_ABI_VERSION 0 + +/* Vector value used to disable MSI for queue */ +#define VIRTIO_MSI_NO_VECTOR 0xffff + +/* The bit of the ISR which indicates a device configuration change. */ +#define VIRTIO_PCI_ISR_CONFIG 0x2 /* IDs for different capabilities. Must all exist. */ /* FIXME: Do we win from separating ISR, NOTIFY and COMMON? */ -- 1.7.10.4 _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
