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Release 4.14 drivers/virtio/virtio_pci_legacy.c

Directory: drivers/virtio
/*
 * Virtio PCI driver - legacy device support
 *
 * 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
 * Copyright Red Hat, Inc. 2014
 *
 * Authors:
 *  Anthony Liguori  <aliguori@us.ibm.com>
 *  Rusty Russell <rusty@rustcorp.com.au>
 *  Michael S. Tsirkin <mst@redhat.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 "virtio_pci_common.h"

/* virtio config->get_features() implementation */

static u64 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); }

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Michael S. Tsirkin32100.00%1100.00%
Total32100.00%1100.00%

/* virtio config->finalize_features() implementation */
static int 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); /* Make sure we don't have any features > 32 bits! */ BUG_ON((u32)vdev->features != vdev->features); /* We only support 32 feature bits. */ iowrite32(vdev->features, vp_dev->ioaddr + VIRTIO_PCI_GUEST_FEATURES); return 0; }

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Michael S. Tsirkin59100.00%1100.00%
Total59100.00%1100.00%

/* 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); }

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Michael S. Tsirkin81100.00%1100.00%
Total81100.00%1100.00%

/* 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); }

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Michael S. Tsirkin83100.00%1100.00%
Total83100.00%1100.00%

/* 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); }

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Michael S. Tsirkin31100.00%1100.00%
Total31100.00%1100.00%


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); }

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Michael S. Tsirkin43100.00%1100.00%
Total43100.00%1100.00%


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); }

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Michael S. Tsirkin49100.00%1100.00%
Total49100.00%1100.00%


static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector) { /* Setup the vector used for configuration events */ iowrite16(vector, vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); /* Verify we had enough resources to assign the vector */ /* Will also flush the write out to device */ return ioread16(vp_dev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); }

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Michael S. Tsirkin38100.00%1100.00%
Total38100.00%1100.00%


static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, struct virtio_pci_vq_info *info, unsigned index, void (*callback)(struct virtqueue *vq), const char *name, bool ctx, u16 msix_vec) { struct virtqueue *vq; 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); info->msix_vector = msix_vec; /* create the vring */ vq = vring_create_virtqueue(index, num, VIRTIO_PCI_VRING_ALIGN, &vp_dev->vdev, true, false, ctx, vp_notify, callback, name); if (!vq) return ERR_PTR(-ENOMEM); /* activate the queue */ iowrite32(virtqueue_get_desc_addr(vq) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); vq->priv = (void __force *)vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY; 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_deactivate; } } return vq; out_deactivate: iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); vring_del_virtqueue(vq); return ERR_PTR(err); }

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Michael S. Tsirkin22689.68%375.00%
Andrew Lutomirski2610.32%125.00%
Total252100.00%4100.00%


static void del_vq(struct virtio_pci_vq_info *info) { struct virtqueue *vq = info->vq; struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); 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); } /* Select and deactivate the queue */ iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); vring_del_virtqueue(vq); }

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Michael S. Tsirkin8795.60%250.00%
Christoph Hellwig22.20%125.00%
Andrew Lutomirski22.20%125.00%
Total91100.00%4100.00%

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, .get_vq_affinity = vp_get_vq_affinity, }; /* the PCI probing function */
int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev) { struct pci_dev *pci_dev = vp_dev->pci_dev; int rc; /* 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; } rc = dma_set_mask(&pci_dev->dev, DMA_BIT_MASK(64)); if (rc) { rc = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(32)); } else { /* * The virtio ring base address is expressed as a 32-bit PFN, * with a page size of 1 << VIRTIO_PCI_QUEUE_ADDR_SHIFT. */ dma_set_coherent_mask(&pci_dev->dev, DMA_BIT_MASK(32 + VIRTIO_PCI_QUEUE_ADDR_SHIFT)); } if (rc) dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n"); rc = pci_request_region(pci_dev, 0, "virtio-pci-legacy"); if (rc) return rc; rc = -ENOMEM; vp_dev->ioaddr = pci_iomap(pci_dev, 0, 0); if (!vp_dev->ioaddr) goto err_iomap; vp_dev->isr = vp_dev->ioaddr + VIRTIO_PCI_ISR; /* 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; vp_dev->vdev.config = &virtio_pci_config_ops; vp_dev->config_vector = vp_config_vector; vp_dev->setup_vq = setup_vq; vp_dev->del_vq = del_vq; return 0; err_iomap: pci_release_region(pci_dev, 0); return rc; }

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Michael S. Tsirkin14957.53%350.00%
Andrew Lutomirski4718.15%116.67%
Gerd Hoffmann4115.83%116.67%
Will Deacon228.49%116.67%
Total259100.00%6100.00%


void virtio_pci_legacy_remove(struct virtio_pci_device *vp_dev) { struct pci_dev *pci_dev = vp_dev->pci_dev; pci_iounmap(pci_dev, vp_dev->ioaddr); pci_release_region(pci_dev, 0); }

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Michael S. Tsirkin2880.00%375.00%
Gerd Hoffmann720.00%125.00%
Total35100.00%4100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Michael S. Tsirkin97986.56%758.33%
Andrew Lutomirski756.63%18.33%
Gerd Hoffmann484.24%18.33%
Will Deacon221.95%18.33%
Christoph Hellwig70.62%216.67%
Total1131100.00%12100.00%
Directory: drivers/virtio
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