struct pci_dev *pci_dev;
/* the IO mapping for the PCI config space */
- void *ioaddr;
+ 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;
+ /* 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;
+ /* 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 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. */
/* A PCI device has it's own struct device and so does a virtio device so
* we create a place for the virtio devices to show up in sysfs. I think it
* would make more sense for virtio to not insist on having it's own device. */
-static struct device virtio_pci_root = {
- .parent = NULL,
- .bus_id = "virtio-pci",
-};
-
-/* Unique numbering for devices under the kvm root */
-static unsigned int dev_index;
+static struct device *virtio_pci_root;
/* 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->feature() implementation */
-static bool vp_feature(struct virtio_device *vdev, unsigned bit)
+/* virtio config->get_features() implementation */
+static u32 vp_get_features(struct virtio_device *vdev)
+{
+ struct virtio_pci_device *vp_dev = to_vp_device(vdev);
+
+ /* When someone needs more than 32 feature bits, we'll need to
+ * steal a bit to indicate that the rest are somewhere else. */
+ 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);
- u32 mask;
-
- /* Since this function is supposed to have the side effect of
- * enabling a queried feature, we simulate that by doing a read
- * from the host feature bitmask and then writing to the guest
- * feature bitmask */
- mask = ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES);
- if (mask & (1 << bit)) {
- mask |= (1 << bit);
- iowrite32(mask, vp_dev->ioaddr + VIRTIO_PCI_GUEST_FEATURES);
- }
- return !!(mask & (1 << bit));
+ /* Give virtio_ring a chance to accept features. */
+ vring_transport_features(vdev);
+
+ /* We only support 32 feature bits. */
+ BUILD_BUG_ON(ARRAY_SIZE(vdev->features) != 1);
+ iowrite32(vdev->features[0], vp_dev->ioaddr+VIRTIO_PCI_GUEST_FEATURES);
}
/* virtio config->get() implementation */
void *buf, unsigned len)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- void *ioaddr = vp_dev->ioaddr + VIRTIO_PCI_CONFIG + offset;
+ void __iomem *ioaddr = vp_dev->ioaddr +
+ VIRTIO_PCI_CONFIG(vp_dev) + offset;
u8 *ptr = buf;
int i;
const void *buf, unsigned len)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- void *ioaddr = vp_dev->ioaddr + VIRTIO_PCI_CONFIG + offset;
+ void __iomem *ioaddr = vp_dev->ioaddr +
+ VIRTIO_PCI_CONFIG(vp_dev) + offset;
const u8 *ptr = buf;
int i;
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
/* We should never be setting status to 0. */
BUG_ON(status == 0);
- return iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
+ iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
}
static void vp_reset(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
/* 0 status means a reset. */
- return iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
+ iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
}
/* the notify function used when creating a virt queue */
iowrite16(info->queue_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
static irqreturn_t vp_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;
u8 isr;
/* reading the ISR has the effect of also clearing it so it's very
return IRQ_NONE;
/* Configuration change? Tell driver if it wants to know. */
- if (isr & VIRTIO_PCI_ISR_CONFIG) {
- struct virtio_driver *drv;
- drv = container_of(vp_dev->vdev.dev.driver,
- struct virtio_driver, driver);
+ if (isr & VIRTIO_PCI_ISR_CONFIG)
+ vp_config_changed(irq, opaque);
+
+ return vp_vring_interrupt(irq, opaque);
+}
- if (drv->config_changed)
- drv->config_changed(&vp_dev->vdev);
+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;
}
- 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;
+ for (i = 0; i < vp_dev->msix_used_vectors; ++i)
+ free_irq(vp_dev->msix_entries[i].vector, vp_dev);
+
+ 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;
}
- spin_unlock_irqrestore(&vp_dev->lock, flags);
- return ret;
+ 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;
}
-/* the config->find_vq() implementation */
-static struct virtqueue *vp_find_vq(struct virtio_device *vdev, unsigned index,
- void (*callback)(struct virtqueue *vq))
+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;
+
+ 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;
+ unsigned long flags, size;
u16 num;
int err;
info->queue_index = index;
info->num = num;
+ info->msix_vector = msix_vec;
- info->queue = kzalloc(PAGE_ALIGN(vring_size(num,PAGE_SIZE)), GFP_KERNEL);
+ 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) >> PAGE_SHIFT,
+ 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(info->num, vdev, info->queue,
- vp_notify, callback);
+ vq = vring_new_virtqueue(info->num, VIRTIO_PCI_VRING_ALIGN,
+ vdev, 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;
+ }
+ }
+
spin_lock_irqsave(&vp_dev->lock, flags);
list_add(&info->node, &vp_dev->virtqueues);
spin_unlock_irqrestore(&vp_dev->lock, flags);
return vq;
+out_assign:
+ vring_del_virtqueue(vq);
out_activate_queue:
iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
- kfree(info->queue);
+ free_pages_exact(info->queue, size);
out_info:
kfree(info);
return ERR_PTR(err);
}
-/* the config->del_vq() implementation */
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;
+ unsigned long flags, size;
spin_lock_irqsave(&vp_dev->lock, flags);
list_del(&info->node);
spin_unlock_irqrestore(&vp_dev->lock, flags);
+ iowrite16(info->queue_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 */
- iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
- kfree(info->queue);
+ 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)
+ 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 (!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 struct virtio_config_ops virtio_pci_config_ops = {
- .feature = vp_feature,
.get = vp_get,
.set = vp_set,
.get_status = vp_get_status,
.set_status = vp_set_status,
.reset = vp_reset,
- .find_vq = vp_find_vq,
- .del_vq = vp_del_vq,
+ .find_vqs = vp_find_vqs,
+ .del_vqs = vp_del_vqs,
+ .get_features = vp_get_features,
+ .finalize_features = vp_finalize_features,
};
+static void virtio_pci_release_dev(struct device *_d)
+{
+ struct virtio_device *dev = container_of(_d, struct virtio_device, dev);
+ struct virtio_pci_device *vp_dev = to_vp_device(dev);
+ struct pci_dev *pci_dev = vp_dev->pci_dev;
+
+ vp_del_vqs(dev);
+ 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);
+}
+
/* the PCI probing function */
static int __devinit virtio_pci_probe(struct pci_dev *pci_dev,
const struct pci_device_id *id)
if (vp_dev == NULL)
return -ENOMEM;
- snprintf(vp_dev->vdev.dev.bus_id, BUS_ID_SIZE, "virtio%d", dev_index);
- vp_dev->vdev.index = dev_index;
- dev_index++;
-
- vp_dev->vdev.dev.parent = &virtio_pci_root;
+ vp_dev->vdev.dev.parent = virtio_pci_root;
+ 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);
vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor;
vp_dev->vdev.id.device = pci_dev->subsystem_device;
- /* register a handler for the queue with the PCI device's interrupt */
- err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, IRQF_SHARED,
- vp_dev->vdev.dev.bus_id, vp_dev);
- if (err)
- goto out_set_drvdata;
-
/* finally register the virtio device */
err = register_virtio_device(&vp_dev->vdev);
if (err)
- goto out_req_irq;
+ goto out_set_drvdata;
return 0;
-out_req_irq:
- free_irq(pci_dev->irq, vp_dev);
out_set_drvdata:
pci_set_drvdata(pci_dev, NULL);
pci_iounmap(pci_dev, vp_dev->ioaddr);
{
struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
- free_irq(pci_dev->irq, vp_dev);
- 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);
+ unregister_virtio_device(&vp_dev->vdev);
}
#ifdef CONFIG_PM
{
int err;
- err = device_register(&virtio_pci_root);
- if (err)
- return err;
+ virtio_pci_root = root_device_register("virtio-pci");
+ if (IS_ERR(virtio_pci_root))
+ return PTR_ERR(virtio_pci_root);
err = pci_register_driver(&virtio_pci_driver);
if (err)
- device_unregister(&virtio_pci_root);
+ root_device_unregister(virtio_pci_root);
return err;
}
static void __exit virtio_pci_exit(void)
{
- device_unregister(&virtio_pci_root);
pci_unregister_driver(&virtio_pci_driver);
+ root_device_unregister(virtio_pci_root);
}
module_exit(virtio_pci_exit);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff