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linux-next/drivers/virtio/virtio_pci_modern.c
Thomas Gleixner f33f5fe256 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 78
Based on 1 normalized pattern(s):

  this work is licensed under the terms of the gnu gpl version 2 or
  later see the copying file in the top level directory

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 6 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520075210.858783702@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:37:51 +02:00

735 lines
21 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Virtio PCI driver - modern (virtio 1.0) 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>
*/
#include <linux/delay.h>
#define VIRTIO_PCI_NO_LEGACY
#include "virtio_pci_common.h"
/*
* Type-safe wrappers for io accesses.
* Use these to enforce at compile time the following spec requirement:
*
* The driver MUST access each field using the “natural” access
* method, i.e. 32-bit accesses for 32-bit fields, 16-bit accesses
* for 16-bit fields and 8-bit accesses for 8-bit fields.
*/
static inline u8 vp_ioread8(u8 __iomem *addr)
{
return ioread8(addr);
}
static inline u16 vp_ioread16 (__le16 __iomem *addr)
{
return ioread16(addr);
}
static inline u32 vp_ioread32(__le32 __iomem *addr)
{
return ioread32(addr);
}
static inline void vp_iowrite8(u8 value, u8 __iomem *addr)
{
iowrite8(value, addr);
}
static inline void vp_iowrite16(u16 value, __le16 __iomem *addr)
{
iowrite16(value, addr);
}
static inline void vp_iowrite32(u32 value, __le32 __iomem *addr)
{
iowrite32(value, addr);
}
static void vp_iowrite64_twopart(u64 val,
__le32 __iomem *lo, __le32 __iomem *hi)
{
vp_iowrite32((u32)val, lo);
vp_iowrite32(val >> 32, hi);
}
static void __iomem *map_capability(struct pci_dev *dev, int off,
size_t minlen,
u32 align,
u32 start, u32 size,
size_t *len)
{
u8 bar;
u32 offset, length;
void __iomem *p;
pci_read_config_byte(dev, off + offsetof(struct virtio_pci_cap,
bar),
&bar);
pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, offset),
&offset);
pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, length),
&length);
if (length <= start) {
dev_err(&dev->dev,
"virtio_pci: bad capability len %u (>%u expected)\n",
length, start);
return NULL;
}
if (length - start < minlen) {
dev_err(&dev->dev,
"virtio_pci: bad capability len %u (>=%zu expected)\n",
length, minlen);
return NULL;
}
length -= start;
if (start + offset < offset) {
dev_err(&dev->dev,
"virtio_pci: map wrap-around %u+%u\n",
start, offset);
return NULL;
}
offset += start;
if (offset & (align - 1)) {
dev_err(&dev->dev,
"virtio_pci: offset %u not aligned to %u\n",
offset, align);
return NULL;
}
if (length > size)
length = size;
if (len)
*len = length;
if (minlen + offset < minlen ||
minlen + offset > pci_resource_len(dev, bar)) {
dev_err(&dev->dev,
"virtio_pci: map virtio %zu@%u "
"out of range on bar %i length %lu\n",
minlen, offset,
bar, (unsigned long)pci_resource_len(dev, bar));
return NULL;
}
p = pci_iomap_range(dev, bar, offset, length);
if (!p)
dev_err(&dev->dev,
"virtio_pci: unable to map virtio %u@%u on bar %i\n",
length, offset, bar);
return p;
}
/* virtio config->get_features() implementation */
static u64 vp_get_features(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
u64 features;
vp_iowrite32(0, &vp_dev->common->device_feature_select);
features = vp_ioread32(&vp_dev->common->device_feature);
vp_iowrite32(1, &vp_dev->common->device_feature_select);
features |= ((u64)vp_ioread32(&vp_dev->common->device_feature) << 32);
return features;
}
static void vp_transport_features(struct virtio_device *vdev, u64 features)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
struct pci_dev *pci_dev = vp_dev->pci_dev;
if ((features & BIT_ULL(VIRTIO_F_SR_IOV)) &&
pci_find_ext_capability(pci_dev, PCI_EXT_CAP_ID_SRIOV))
__virtio_set_bit(vdev, VIRTIO_F_SR_IOV);
}
/* virtio config->finalize_features() implementation */
static int vp_finalize_features(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
u64 features = vdev->features;
/* Give virtio_ring a chance to accept features. */
vring_transport_features(vdev);
/* Give virtio_pci a chance to accept features. */
vp_transport_features(vdev, features);
if (!__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
dev_err(&vdev->dev, "virtio: device uses modern interface "
"but does not have VIRTIO_F_VERSION_1\n");
return -EINVAL;
}
vp_iowrite32(0, &vp_dev->common->guest_feature_select);
vp_iowrite32((u32)vdev->features, &vp_dev->common->guest_feature);
vp_iowrite32(1, &vp_dev->common->guest_feature_select);
vp_iowrite32(vdev->features >> 32, &vp_dev->common->guest_feature);
return 0;
}
/* 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);
u8 b;
__le16 w;
__le32 l;
BUG_ON(offset + len > vp_dev->device_len);
switch (len) {
case 1:
b = ioread8(vp_dev->device + offset);
memcpy(buf, &b, sizeof b);
break;
case 2:
w = cpu_to_le16(ioread16(vp_dev->device + offset));
memcpy(buf, &w, sizeof w);
break;
case 4:
l = cpu_to_le32(ioread32(vp_dev->device + offset));
memcpy(buf, &l, sizeof l);
break;
case 8:
l = cpu_to_le32(ioread32(vp_dev->device + offset));
memcpy(buf, &l, sizeof l);
l = cpu_to_le32(ioread32(vp_dev->device + offset + sizeof l));
memcpy(buf + sizeof l, &l, sizeof l);
break;
default:
BUG();
}
}
/* 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);
u8 b;
__le16 w;
__le32 l;
BUG_ON(offset + len > vp_dev->device_len);
switch (len) {
case 1:
memcpy(&b, buf, sizeof b);
iowrite8(b, vp_dev->device + offset);
break;
case 2:
memcpy(&w, buf, sizeof w);
iowrite16(le16_to_cpu(w), vp_dev->device + offset);
break;
case 4:
memcpy(&l, buf, sizeof l);
iowrite32(le32_to_cpu(l), vp_dev->device + offset);
break;
case 8:
memcpy(&l, buf, sizeof l);
iowrite32(le32_to_cpu(l), vp_dev->device + offset);
memcpy(&l, buf + sizeof l, sizeof l);
iowrite32(le32_to_cpu(l), vp_dev->device + offset + sizeof l);
break;
default:
BUG();
}
}
static u32 vp_generation(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
return vp_ioread8(&vp_dev->common->config_generation);
}
/* 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 vp_ioread8(&vp_dev->common->device_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);
vp_iowrite8(status, &vp_dev->common->device_status);
}
static void vp_reset(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
/* 0 status means a reset. */
vp_iowrite8(0, &vp_dev->common->device_status);
/* After writing 0 to device_status, the driver MUST wait for a read of
* device_status to return 0 before reinitializing the device.
* This will flush out the status write, and flush in device writes,
* including MSI-X interrupts, if any.
*/
while (vp_ioread8(&vp_dev->common->device_status))
msleep(1);
/* Flush pending VQ/configuration callbacks. */
vp_synchronize_vectors(vdev);
}
static u16 vp_config_vector(struct virtio_pci_device *vp_dev, u16 vector)
{
/* Setup the vector used for configuration events */
vp_iowrite16(vector, &vp_dev->common->msix_config);
/* Verify we had enough resources to assign the vector */
/* Will also flush the write out to device */
return vp_ioread16(&vp_dev->common->msix_config);
}
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 virtio_pci_common_cfg __iomem *cfg = vp_dev->common;
struct virtqueue *vq;
u16 num, off;
int err;
if (index >= vp_ioread16(&cfg->num_queues))
return ERR_PTR(-ENOENT);
/* Select the queue we're interested in */
vp_iowrite16(index, &cfg->queue_select);
/* Check if queue is either not available or already active. */
num = vp_ioread16(&cfg->queue_size);
if (!num || vp_ioread16(&cfg->queue_enable))
return ERR_PTR(-ENOENT);
if (num & (num - 1)) {
dev_warn(&vp_dev->pci_dev->dev, "bad queue size %u", num);
return ERR_PTR(-EINVAL);
}
/* get offset of notification word for this vq */
off = vp_ioread16(&cfg->queue_notify_off);
info->msix_vector = msix_vec;
/* create the vring */
vq = vring_create_virtqueue(index, num,
SMP_CACHE_BYTES, &vp_dev->vdev,
true, true, ctx,
vp_notify, callback, name);
if (!vq)
return ERR_PTR(-ENOMEM);
/* activate the queue */
vp_iowrite16(virtqueue_get_vring_size(vq), &cfg->queue_size);
vp_iowrite64_twopart(virtqueue_get_desc_addr(vq),
&cfg->queue_desc_lo, &cfg->queue_desc_hi);
vp_iowrite64_twopart(virtqueue_get_avail_addr(vq),
&cfg->queue_avail_lo, &cfg->queue_avail_hi);
vp_iowrite64_twopart(virtqueue_get_used_addr(vq),
&cfg->queue_used_lo, &cfg->queue_used_hi);
if (vp_dev->notify_base) {
/* offset should not wrap */
if ((u64)off * vp_dev->notify_offset_multiplier + 2
> vp_dev->notify_len) {
dev_warn(&vp_dev->pci_dev->dev,
"bad notification offset %u (x %u) "
"for queue %u > %zd",
off, vp_dev->notify_offset_multiplier,
index, vp_dev->notify_len);
err = -EINVAL;
goto err_map_notify;
}
vq->priv = (void __force *)vp_dev->notify_base +
off * vp_dev->notify_offset_multiplier;
} else {
vq->priv = (void __force *)map_capability(vp_dev->pci_dev,
vp_dev->notify_map_cap, 2, 2,
off * vp_dev->notify_offset_multiplier, 2,
NULL);
}
if (!vq->priv) {
err = -ENOMEM;
goto err_map_notify;
}
if (msix_vec != VIRTIO_MSI_NO_VECTOR) {
vp_iowrite16(msix_vec, &cfg->queue_msix_vector);
msix_vec = vp_ioread16(&cfg->queue_msix_vector);
if (msix_vec == VIRTIO_MSI_NO_VECTOR) {
err = -EBUSY;
goto err_assign_vector;
}
}
return vq;
err_assign_vector:
if (!vp_dev->notify_base)
pci_iounmap(vp_dev->pci_dev, (void __iomem __force *)vq->priv);
err_map_notify:
vring_del_virtqueue(vq);
return ERR_PTR(err);
}
static int vp_modern_find_vqs(struct virtio_device *vdev, unsigned nvqs,
struct virtqueue *vqs[],
vq_callback_t *callbacks[],
const char * const names[], const bool *ctx,
struct irq_affinity *desc)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
struct virtqueue *vq;
int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names, ctx, desc);
if (rc)
return rc;
/* Select and activate all queues. Has to be done last: once we do
* this, there's no way to go back except reset.
*/
list_for_each_entry(vq, &vdev->vqs, list) {
vp_iowrite16(vq->index, &vp_dev->common->queue_select);
vp_iowrite16(1, &vp_dev->common->queue_enable);
}
return 0;
}
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);
vp_iowrite16(vq->index, &vp_dev->common->queue_select);
if (vp_dev->msix_enabled) {
vp_iowrite16(VIRTIO_MSI_NO_VECTOR,
&vp_dev->common->queue_msix_vector);
/* Flush the write out to device */
vp_ioread16(&vp_dev->common->queue_msix_vector);
}
if (!vp_dev->notify_base)
pci_iounmap(vp_dev->pci_dev, (void __force __iomem *)vq->priv);
vring_del_virtqueue(vq);
}
static const struct virtio_config_ops virtio_pci_config_nodev_ops = {
.get = NULL,
.set = NULL,
.generation = vp_generation,
.get_status = vp_get_status,
.set_status = vp_set_status,
.reset = vp_reset,
.find_vqs = vp_modern_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,
};
static const struct virtio_config_ops virtio_pci_config_ops = {
.get = vp_get,
.set = vp_set,
.generation = vp_generation,
.get_status = vp_get_status,
.set_status = vp_set_status,
.reset = vp_reset,
.find_vqs = vp_modern_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,
};
/**
* virtio_pci_find_capability - walk capabilities to find device info.
* @dev: the pci device
* @cfg_type: the VIRTIO_PCI_CAP_* value we seek
* @ioresource_types: IORESOURCE_MEM and/or IORESOURCE_IO.
*
* Returns offset of the capability, or 0.
*/
static inline int virtio_pci_find_capability(struct pci_dev *dev, u8 cfg_type,
u32 ioresource_types, int *bars)
{
int pos;
for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR);
pos > 0;
pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) {
u8 type, bar;
pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap,
cfg_type),
&type);
pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap,
bar),
&bar);
/* Ignore structures with reserved BAR values */
if (bar > 0x5)
continue;
if (type == cfg_type) {
if (pci_resource_len(dev, bar) &&
pci_resource_flags(dev, bar) & ioresource_types) {
*bars |= (1 << bar);
return pos;
}
}
}
return 0;
}
/* This is part of the ABI. Don't screw with it. */
static inline void check_offsets(void)
{
/* Note: disk space was harmed in compilation of this function. */
BUILD_BUG_ON(VIRTIO_PCI_CAP_VNDR !=
offsetof(struct virtio_pci_cap, cap_vndr));
BUILD_BUG_ON(VIRTIO_PCI_CAP_NEXT !=
offsetof(struct virtio_pci_cap, cap_next));
BUILD_BUG_ON(VIRTIO_PCI_CAP_LEN !=
offsetof(struct virtio_pci_cap, cap_len));
BUILD_BUG_ON(VIRTIO_PCI_CAP_CFG_TYPE !=
offsetof(struct virtio_pci_cap, cfg_type));
BUILD_BUG_ON(VIRTIO_PCI_CAP_BAR !=
offsetof(struct virtio_pci_cap, bar));
BUILD_BUG_ON(VIRTIO_PCI_CAP_OFFSET !=
offsetof(struct virtio_pci_cap, offset));
BUILD_BUG_ON(VIRTIO_PCI_CAP_LENGTH !=
offsetof(struct virtio_pci_cap, length));
BUILD_BUG_ON(VIRTIO_PCI_NOTIFY_CAP_MULT !=
offsetof(struct virtio_pci_notify_cap,
notify_off_multiplier));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_DFSELECT !=
offsetof(struct virtio_pci_common_cfg,
device_feature_select));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_DF !=
offsetof(struct virtio_pci_common_cfg, device_feature));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_GFSELECT !=
offsetof(struct virtio_pci_common_cfg,
guest_feature_select));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_GF !=
offsetof(struct virtio_pci_common_cfg, guest_feature));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_MSIX !=
offsetof(struct virtio_pci_common_cfg, msix_config));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_NUMQ !=
offsetof(struct virtio_pci_common_cfg, num_queues));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_STATUS !=
offsetof(struct virtio_pci_common_cfg, device_status));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_CFGGENERATION !=
offsetof(struct virtio_pci_common_cfg, config_generation));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SELECT !=
offsetof(struct virtio_pci_common_cfg, queue_select));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_SIZE !=
offsetof(struct virtio_pci_common_cfg, queue_size));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_MSIX !=
offsetof(struct virtio_pci_common_cfg, queue_msix_vector));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_ENABLE !=
offsetof(struct virtio_pci_common_cfg, queue_enable));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_NOFF !=
offsetof(struct virtio_pci_common_cfg, queue_notify_off));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCLO !=
offsetof(struct virtio_pci_common_cfg, queue_desc_lo));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_DESCHI !=
offsetof(struct virtio_pci_common_cfg, queue_desc_hi));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILLO !=
offsetof(struct virtio_pci_common_cfg, queue_avail_lo));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_AVAILHI !=
offsetof(struct virtio_pci_common_cfg, queue_avail_hi));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDLO !=
offsetof(struct virtio_pci_common_cfg, queue_used_lo));
BUILD_BUG_ON(VIRTIO_PCI_COMMON_Q_USEDHI !=
offsetof(struct virtio_pci_common_cfg, queue_used_hi));
}
/* the PCI probing function */
int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)
{
struct pci_dev *pci_dev = vp_dev->pci_dev;
int err, common, isr, notify, device;
u32 notify_length;
u32 notify_offset;
check_offsets();
/* We only own devices >= 0x1000 and <= 0x107f: leave the rest. */
if (pci_dev->device < 0x1000 || pci_dev->device > 0x107f)
return -ENODEV;
if (pci_dev->device < 0x1040) {
/* Transitional devices: use the PCI subsystem device id as
* virtio device id, same as legacy driver always did.
*/
vp_dev->vdev.id.device = pci_dev->subsystem_device;
} else {
/* Modern devices: simply use PCI device id, but start from 0x1040. */
vp_dev->vdev.id.device = pci_dev->device - 0x1040;
}
vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor;
/* check for a common config: if not, use legacy mode (bar 0). */
common = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_COMMON_CFG,
IORESOURCE_IO | IORESOURCE_MEM,
&vp_dev->modern_bars);
if (!common) {
dev_info(&pci_dev->dev,
"virtio_pci: leaving for legacy driver\n");
return -ENODEV;
}
/* If common is there, these should be too... */
isr = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_ISR_CFG,
IORESOURCE_IO | IORESOURCE_MEM,
&vp_dev->modern_bars);
notify = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG,
IORESOURCE_IO | IORESOURCE_MEM,
&vp_dev->modern_bars);
if (!isr || !notify) {
dev_err(&pci_dev->dev,
"virtio_pci: missing capabilities %i/%i/%i\n",
common, isr, notify);
return -EINVAL;
}
err = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(64));
if (err)
err = dma_set_mask_and_coherent(&pci_dev->dev,
DMA_BIT_MASK(32));
if (err)
dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n");
/* Device capability is only mandatory for devices that have
* device-specific configuration.
*/
device = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG,
IORESOURCE_IO | IORESOURCE_MEM,
&vp_dev->modern_bars);
err = pci_request_selected_regions(pci_dev, vp_dev->modern_bars,
"virtio-pci-modern");
if (err)
return err;
err = -EINVAL;
vp_dev->common = map_capability(pci_dev, common,
sizeof(struct virtio_pci_common_cfg), 4,
0, sizeof(struct virtio_pci_common_cfg),
NULL);
if (!vp_dev->common)
goto err_map_common;
vp_dev->isr = map_capability(pci_dev, isr, sizeof(u8), 1,
0, 1,
NULL);
if (!vp_dev->isr)
goto err_map_isr;
/* Read notify_off_multiplier from config space. */
pci_read_config_dword(pci_dev,
notify + offsetof(struct virtio_pci_notify_cap,
notify_off_multiplier),
&vp_dev->notify_offset_multiplier);
/* Read notify length and offset from config space. */
pci_read_config_dword(pci_dev,
notify + offsetof(struct virtio_pci_notify_cap,
cap.length),
&notify_length);
pci_read_config_dword(pci_dev,
notify + offsetof(struct virtio_pci_notify_cap,
cap.offset),
&notify_offset);
/* We don't know how many VQs we'll map, ahead of the time.
* If notify length is small, map it all now.
* Otherwise, map each VQ individually later.
*/
if ((u64)notify_length + (notify_offset % PAGE_SIZE) <= PAGE_SIZE) {
vp_dev->notify_base = map_capability(pci_dev, notify, 2, 2,
0, notify_length,
&vp_dev->notify_len);
if (!vp_dev->notify_base)
goto err_map_notify;
} else {
vp_dev->notify_map_cap = notify;
}
/* Again, we don't know how much we should map, but PAGE_SIZE
* is more than enough for all existing devices.
*/
if (device) {
vp_dev->device = map_capability(pci_dev, device, 0, 4,
0, PAGE_SIZE,
&vp_dev->device_len);
if (!vp_dev->device)
goto err_map_device;
vp_dev->vdev.config = &virtio_pci_config_ops;
} else {
vp_dev->vdev.config = &virtio_pci_config_nodev_ops;
}
vp_dev->config_vector = vp_config_vector;
vp_dev->setup_vq = setup_vq;
vp_dev->del_vq = del_vq;
return 0;
err_map_device:
if (vp_dev->notify_base)
pci_iounmap(pci_dev, vp_dev->notify_base);
err_map_notify:
pci_iounmap(pci_dev, vp_dev->isr);
err_map_isr:
pci_iounmap(pci_dev, vp_dev->common);
err_map_common:
return err;
}
void virtio_pci_modern_remove(struct virtio_pci_device *vp_dev)
{
struct pci_dev *pci_dev = vp_dev->pci_dev;
if (vp_dev->device)
pci_iounmap(pci_dev, vp_dev->device);
if (vp_dev->notify_base)
pci_iounmap(pci_dev, vp_dev->notify_base);
pci_iounmap(pci_dev, vp_dev->isr);
pci_iounmap(pci_dev, vp_dev->common);
pci_release_selected_regions(pci_dev, vp_dev->modern_bars);
}