mirror of https://gitee.com/openkylin/linux.git
830 lines
22 KiB
C
830 lines
22 KiB
C
/*
|
|
* 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 <aliguori@us.ibm.com>
|
|
*
|
|
* 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 <aliguori@us.ibm.com>");
|
|
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 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);
|
|
|
|
/* 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 */
|
|
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);
|
|
}
|
|
|
|
/* the config->set() implementation. it's symmetric to the config->get()
|
|
* implementation */
|
|
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);
|
|
}
|
|
|
|
/* 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 bool 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);
|
|
return true;
|
|
}
|
|
|
|
/* 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_vectors = nvectors;
|
|
|
|
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;
|
|
|
|
err = pci_enable_msix_exact(vp_dev->pci_dev,
|
|
vp_dev->msix_entries, nvectors);
|
|
if (err)
|
|
goto error;
|
|
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 = {
|
|
.get = vp_get,
|
|
.set = vp_set,
|
|
.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_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_iounmap(pci_dev, vp_dev->ioaddr);
|
|
pci_release_regions(pci_dev);
|
|
pci_disable_device(pci_dev);
|
|
kfree(vp_dev);
|
|
}
|
|
|
|
#ifdef CONFIG_PM_SLEEP
|
|
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_SLEEP
|
|
.driver.pm = &virtio_pci_pm_ops,
|
|
#endif
|
|
};
|
|
|
|
module_pci_driver(virtio_pci_driver);
|