/*
* Virtio PCI Bindings
*
* Copyright IBM, Corp. 2007
* Copyright (c) 2009 CodeSourcery
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
* Paul Brook <paul@codesourcery.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
* Contributions after 2012-01-13 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
*/
#include "qemu/osdep.h"
#include "exec/memop.h"
#include "standard-headers/linux/virtio_pci.h"
#include "hw/boards.h"
#include "hw/virtio/virtio.h"
#include "migration/qemu-file-types.h"
#include "hw/pci/pci.h"
#include "hw/pci/pci_bus.h"
#include "hw/qdev-properties.h"
#include "qapi/error.h"
#include "qemu/error-report.h"
#include "qemu/log.h"
#include "qemu/module.h"
#include "hw/pci/msi.h"
#include "hw/pci/msix.h"
#include "hw/loader.h"
#include "sysemu/kvm.h"
#include "virtio-pci.h"
#include "qemu/range.h"
#include "hw/virtio/virtio-bus.h"
#include "qapi/visitor.h"
#define VIRTIO_PCI_REGION_SIZE(dev) VIRTIO_PCI_CONFIG_OFF(msix_present(dev))
#undef VIRTIO_PCI_CONFIG
/* The remaining space is defined by each driver as the per-driver
* configuration space */
#define VIRTIO_PCI_CONFIG_SIZE(dev) VIRTIO_PCI_CONFIG_OFF(msix_enabled(dev))
static void virtio_pci_bus_new(VirtioBusState *bus, size_t bus_size,
VirtIOPCIProxy *dev);
static void virtio_pci_reset(DeviceState *qdev);
/* virtio device */
/* DeviceState to VirtIOPCIProxy. For use off data-path. TODO: use QOM. */
static inline VirtIOPCIProxy *to_virtio_pci_proxy(DeviceState *d)
{
return container_of(d, VirtIOPCIProxy, pci_dev.qdev);
}
/* DeviceState to VirtIOPCIProxy. Note: used on datapath,
* be careful and test performance if you change this.
*/
static inline VirtIOPCIProxy *to_virtio_pci_proxy_fast(DeviceState *d)
{
return container_of(d, VirtIOPCIProxy, pci_dev.qdev);
}
static void virtio_pci_notify(DeviceState *d, uint16_t vector)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy_fast(d);
if (msix_enabled(&proxy->pci_dev))
msix_notify(&proxy->pci_dev, vector);
else {
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
pci_set_irq(&proxy->pci_dev, qatomic_read(&vdev->isr) & 1);
}
}
static void virtio_pci_save_config(DeviceState *d, QEMUFile *f)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
pci_device_save(&proxy->pci_dev, f);
msix_save(&proxy->pci_dev, f);
if (msix_present(&proxy->pci_dev))
qemu_put_be16(f, vdev->config_vector);
}
static const VMStateDescription vmstate_virtio_pci_modern_queue_state = {
.name = "virtio_pci/modern_queue_state",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_UINT16(num, VirtIOPCIQueue),
VMSTATE_UNUSED(1), /* enabled was stored as be16 */
VMSTATE_BOOL(enabled, VirtIOPCIQueue),
VMSTATE_UINT32_ARRAY(desc, VirtIOPCIQueue, 2),
VMSTATE_UINT32_ARRAY(avail, VirtIOPCIQueue, 2),
VMSTATE_UINT32_ARRAY(used, VirtIOPCIQueue, 2),
VMSTATE_END_OF_LIST()
}
};
static bool virtio_pci_modern_state_needed(void *opaque)
{
VirtIOPCIProxy *proxy = opaque;
return virtio_pci_modern(proxy);
}
static const VMStateDescription vmstate_virtio_pci_modern_state_sub = {
.name = "virtio_pci/modern_state",
.version_id = 1,
.minimum_version_id = 1,
.needed = &virtio_pci_modern_state_needed,
.fields = (VMStateField[]) {
VMSTATE_UINT32(dfselect, VirtIOPCIProxy),
VMSTATE_UINT32(gfselect, VirtIOPCIProxy),
VMSTATE_UINT32_ARRAY(guest_features, VirtIOPCIProxy, 2),
VMSTATE_STRUCT_ARRAY(vqs, VirtIOPCIProxy, VIRTIO_QUEUE_MAX, 0,
vmstate_virtio_pci_modern_queue_state,
VirtIOPCIQueue),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription vmstate_virtio_pci = {
.name = "virtio_pci",
.version_id = 1,
.minimum_version_id = 1,
.minimum_version_id_old = 1,
.fields = (VMStateField[]) {
VMSTATE_END_OF_LIST()
},
.subsections = (const VMStateDescription*[]) {
&vmstate_virtio_pci_modern_state_sub,
NULL
}
};
static bool virtio_pci_has_extra_state(DeviceState *d)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
return proxy->flags & VIRTIO_PCI_FLAG_MIGRATE_EXTRA;
}
static void virtio_pci_save_extra_state(DeviceState *d, QEMUFile *f)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
vmstate_save_state(f, &vmstate_virtio_pci, proxy, NULL);
}
static int virtio_pci_load_extra_state(DeviceState *d, QEMUFile *f)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
return vmstate_load_state(f, &vmstate_virtio_pci, proxy, 1);
}
static void virtio_pci_save_queue(DeviceState *d, int n, QEMUFile *f)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
if (msix_present(&proxy->pci_dev))
qemu_put_be16(f, virtio_queue_vector(vdev, n));
}
static int virtio_pci_load_config(DeviceState *d, QEMUFile *f)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
int ret;
ret = pci_device_load(&proxy->pci_dev, f);
if (ret) {
return ret;
}
msix_unuse_all_vectors(&proxy->pci_dev);
msix_load(&proxy->pci_dev, f);
if (msix_present(&proxy->pci_dev)) {
qemu_get_be16s(f, &vdev->config_vector);
} else {
vdev->config_vector = VIRTIO_NO_VECTOR;
}
if (vdev->config_vector != VIRTIO_NO_VECTOR) {
return msix_vector_use(&proxy->pci_dev, vdev->config_vector);
}
return 0;
}
static int virtio_pci_load_queue(DeviceState *d, int n, QEMUFile *f)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
uint16_t vector;
if (msix_present(&proxy->pci_dev)) {
qemu_get_be16s(f, &vector);
} else {
vector = VIRTIO_NO_VECTOR;
}
virtio_queue_set_vector(vdev, n, vector);
if (vector != VIRTIO_NO_VECTOR) {
return msix_vector_use(&proxy->pci_dev, vector);
}
return 0;
}
static bool virtio_pci_ioeventfd_enabled(DeviceState *d)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
return (proxy->flags & VIRTIO_PCI_FLAG_USE_IOEVENTFD) != 0;
}
#define QEMU_VIRTIO_PCI_QUEUE_MEM_MULT 0x1000
static inline int virtio_pci_queue_mem_mult(struct VirtIOPCIProxy *proxy)
{
return (proxy->flags & VIRTIO_PCI_FLAG_PAGE_PER_VQ) ?
QEMU_VIRTIO_PCI_QUEUE_MEM_MULT : 4;
}
static int virtio_pci_ioeventfd_assign(DeviceState *d, EventNotifier *notifier,
int n, bool assign)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
VirtQueue *vq = virtio_get_queue(vdev, n);
bool legacy = virtio_pci_legacy(proxy);
bool modern = virtio_pci_modern(proxy);
bool fast_mmio = kvm_ioeventfd_any_length_enabled();
bool modern_pio = proxy->flags & VIRTIO_PCI_FLAG_MODERN_PIO_NOTIFY;
MemoryRegion *modern_mr = &proxy->notify.mr;
MemoryRegion *modern_notify_mr = &proxy->notify_pio.mr;
MemoryRegion *legacy_mr = &proxy->bar;
hwaddr modern_addr = virtio_pci_queue_mem_mult(proxy) *
virtio_get_queue_index(vq);
hwaddr legacy_addr = VIRTIO_PCI_QUEUE_NOTIFY;
if (assign) {
if (modern) {
if (fast_mmio) {
memory_region_add_eventfd(modern_mr, modern_addr, 0,
false, n, notifier);
} else {
memory_region_add_eventfd(modern_mr, modern_addr, 2,
false, n, notifier);
}
if (modern_pio) {
memory_region_add_eventfd(modern_notify_mr, 0, 2,
true, n, notifier);
}
}
if (legacy) {
memory_region_add_eventfd(legacy_mr, legacy_addr, 2,
true, n, notifier);
}
} else {
if (modern) {
if (fast_mmio) {
memory_region_del_eventfd(modern_mr, modern_addr, 0,
false, n, notifier);
} else {
memory_region_del_eventfd(modern_mr, modern_addr, 2,
false, n, notifier);
}
if (modern_pio) {
memory_region_del_eventfd(modern_notify_mr, 0, 2,
true, n, notifier);
}
}
if (legacy) {
memory_region_del_eventfd(legacy_mr, legacy_addr, 2,
true, n, notifier);
}
}
return 0;
}
static void virtio_pci_start_ioeventfd(VirtIOPCIProxy *proxy)
{
virtio_bus_start_ioeventfd(&proxy->bus);
}
static void virtio_pci_stop_ioeventfd(VirtIOPCIProxy *proxy)
{
virtio_bus_stop_ioeventfd(&proxy->bus);
}
static void virtio_ioport_write(void *opaque, uint32_t addr, uint32_t val)
{
VirtIOPCIProxy *proxy = opaque;
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
hwaddr pa;
switch (addr) {
case VIRTIO_PCI_GUEST_FEATURES:
/* Guest does not negotiate properly? We have to assume nothing. */
if (val & (1 << VIRTIO_F_BAD_FEATURE)) {
val = virtio_bus_get_vdev_bad_features(&proxy->bus);
}
virtio_set_features(vdev, val);
break;
case VIRTIO_PCI_QUEUE_PFN:
pa = (hwaddr)val << VIRTIO_PCI_QUEUE_ADDR_SHIFT;
if (pa == 0) {
virtio_pci_reset(DEVICE(proxy));
}
else
virtio_queue_set_addr(vdev, vdev->queue_sel, pa);
break;
case VIRTIO_PCI_QUEUE_SEL:
if (val < VIRTIO_QUEUE_MAX)
vdev->queue_sel = val;
break;
case VIRTIO_PCI_QUEUE_NOTIFY:
if (val < VIRTIO_QUEUE_MAX) {
virtio_queue_notify(vdev, val);
}
break;
case VIRTIO_PCI_STATUS:
if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) {
virtio_pci_stop_ioeventfd(proxy);
}
virtio_set_status(vdev, val & 0xFF);
if (val & VIRTIO_CONFIG_S_DRIVER_OK) {
virtio_pci_start_ioeventfd(proxy);
}
if (vdev->status == 0) {
virtio_pci_reset(DEVICE(proxy));
}
/* Linux before 2.6.34 drives the device without enabling
the PCI device bus master bit. Enable it automatically
for the guest. This is a PCI spec violation but so is
initiating DMA with bus master bit clear. */
if (val == (VIRTIO_CONFIG_S_ACKNOWLEDGE | VIRTIO_CONFIG_S_DRIVER)) {
pci_default_write_config(&proxy->pci_dev, PCI_COMMAND,
proxy->pci_dev.config[PCI_COMMAND] |
PCI_COMMAND_MASTER, 1);
}
break;
case VIRTIO_MSI_CONFIG_VECTOR:
msix_vector_unuse(&proxy->pci_dev, vdev->config_vector);
/* Make it possible for guest to discover an error took place. */
if (msix_vector_use(&proxy->pci_dev, val) < 0)
val = VIRTIO_NO_VECTOR;
vdev->config_vector = val;
break;
case VIRTIO_MSI_QUEUE_VECTOR:
msix_vector_unuse(&proxy->pci_dev,
virtio_queue_vector(vdev, vdev->queue_sel));
/* Make it possible for guest to discover an error took place. */
if (msix_vector_use(&proxy->pci_dev, val) < 0)
val = VIRTIO_NO_VECTOR;
virtio_queue_set_vector(vdev, vdev->queue_sel, val);
break;
default:
qemu_log_mask(LOG_GUEST_ERROR,
"%s: unexpected address 0x%x value 0x%x\n",
__func__, addr, val);
break;
}
}
static uint32_t virtio_ioport_read(VirtIOPCIProxy *proxy, uint32_t addr)
{
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
uint32_t ret = 0xFFFFFFFF;
switch (addr) {
case VIRTIO_PCI_HOST_FEATURES:
ret = vdev->host_features;
break;
case VIRTIO_PCI_GUEST_FEATURES:
ret = vdev->guest_features;
break;
case VIRTIO_PCI_QUEUE_PFN:
ret = virtio_queue_get_addr(vdev, vdev->queue_sel)
>> VIRTIO_PCI_QUEUE_ADDR_SHIFT;
break;
case VIRTIO_PCI_QUEUE_NUM:
ret = virtio_queue_get_num(vdev, vdev->queue_sel);
break;
case VIRTIO_PCI_QUEUE_SEL:
ret = vdev->queue_sel;
break;
case VIRTIO_PCI_STATUS:
ret = vdev->status;
break;
case VIRTIO_PCI_ISR:
/* reading from the ISR also clears it. */
ret = qatomic_xchg(&vdev->isr, 0);
pci_irq_deassert(&proxy->pci_dev);
break;
case VIRTIO_MSI_CONFIG_VECTOR:
ret = vdev->config_vector;
break;
case VIRTIO_MSI_QUEUE_VECTOR:
ret = virtio_queue_vector(vdev, vdev->queue_sel);
break;
default:
break;
}
return ret;
}
static uint64_t virtio_pci_config_read(void *opaque, hwaddr addr,
unsigned size)
{
VirtIOPCIProxy *proxy = opaque;
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
uint32_t config = VIRTIO_PCI_CONFIG_SIZE(&proxy->pci_dev);
uint64_t val = 0;
if (addr < config) {
return virtio_ioport_read(proxy, addr);
}
addr -= config;
switch (size) {
case 1:
val = virtio_config_readb(vdev, addr);
break;
case 2:
val = virtio_config_readw(vdev, addr);
if (virtio_is_big_endian(vdev)) {
val = bswap16(val);
}
break;
case 4:
val = virtio_config_readl(vdev, addr);
if (virtio_is_big_endian(vdev)) {
val = bswap32(val);
}
break;
}
return val;
}
static void virtio_pci_config_write(void *opaque, hwaddr addr,
uint64_t val, unsigned size)
{
VirtIOPCIProxy *proxy = opaque;
uint32_t config = VIRTIO_PCI_CONFIG_SIZE(&proxy->pci_dev);
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
if (addr < config) {
virtio_ioport_write(proxy, addr, val);
return;
}
addr -= config;
/*
* Virtio-PCI is odd. Ioports are LE but config space is target native
* endian.
*/
switch (size) {
case 1:
virtio_config_writeb(vdev, addr, val);
break;
case 2:
if (virtio_is_big_endian(vdev)) {
val = bswap16(val);
}
virtio_config_writew(vdev, addr, val);
break;
case 4:
if (virtio_is_big_endian(vdev)) {
val = bswap32(val);
}
virtio_config_writel(vdev, addr, val);
break;
}
}
static const MemoryRegionOps virtio_pci_config_ops = {
.read = virtio_pci_config_read,
.write = virtio_pci_config_write,
.impl = {
.min_access_size = 1,
.max_access_size = 4,
},
.endianness = DEVICE_LITTLE_ENDIAN,
};
static MemoryRegion *virtio_address_space_lookup(VirtIOPCIProxy *proxy,
hwaddr *off, int len)
{
int i;
VirtIOPCIRegion *reg;
for (i = 0; i < ARRAY_SIZE(proxy->regs); ++i) {
reg = &proxy->regs[i];
if (*off >= reg->offset &&
*off + len <= reg->offset + reg->size) {
*off -= reg->offset;
return ®->mr;
}
}
return NULL;
}
/* Below are generic functions to do memcpy from/to an address space,
* without byteswaps, with input validation.
*
* As regular address_space_* APIs all do some kind of byteswap at least for
* some host/target combinations, we are forced to explicitly convert to a
* known-endianness integer value.
* It doesn't really matter which endian format to go through, so the code
* below selects the endian that causes the least amount of work on the given
* host.
*
* Note: host pointer must be aligned.
*/
static
void virtio_address_space_write(VirtIOPCIProxy *proxy, hwaddr addr,
const uint8_t *buf, int len)
{
uint64_t val;
MemoryRegion *mr;
/* address_space_* APIs assume an aligned address.
* As address is under guest control, handle illegal values.
*/
addr &= ~(len - 1);
mr = virtio_address_space_lookup(proxy, &addr, len);
if (!mr) {
return;
}
/* Make sure caller aligned buf properly */
assert(!(((uintptr_t)buf) & (len - 1)));
switch (len) {
case 1:
val = pci_get_byte(buf);
break;
case 2:
val = pci_get_word(buf);
break;
case 4:
val = pci_get_long(buf);
break;
default:
/* As length is under guest control, handle illegal values. */
return;
}
memory_region_dispatch_write(mr, addr, val, size_memop(len) | MO_LE,
MEMTXATTRS_UNSPECIFIED);
}
static void
virtio_address_space_read(VirtIOPCIProxy *proxy, hwaddr addr,
uint8_t *buf, int len)
{
uint64_t val;
MemoryRegion *mr;
/* address_space_* APIs assume an aligned address.
* As address is under guest control, handle illegal values.
*/
addr &= ~(len - 1);
mr = virtio_address_space_lookup(proxy, &addr, len);
if (!mr) {
return;
}
/* Make sure caller aligned buf properly */
assert(!(((uintptr_t)buf) & (len - 1)));
memory_region_dispatch_read(mr, addr, &val, size_memop(len) | MO_LE,
MEMTXATTRS_UNSPECIFIED);
switch (len) {
case 1:
pci_set_byte(buf, val);
break;
case 2:
pci_set_word(buf, val);
break;
case 4:
pci_set_long(buf, val);
break;
default:
/* As length is under guest control, handle illegal values. */
break;
}
}
static void virtio_write_config(PCIDevice *pci_dev, uint32_t address,
uint32_t val, int len)
{
VirtIOPCIProxy *proxy = VIRTIO_PCI(pci_dev);
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
struct virtio_pci_cfg_cap *cfg;
pci_default_write_config(pci_dev, address, val, len);
if (proxy->flags & VIRTIO_PCI_FLAG_INIT_FLR) {
pcie_cap_flr_write_config(pci_dev, address, val, len);
}
if (range_covers_byte(address, len, PCI_COMMAND)) {
if (!(pci_dev->config[PCI_COMMAND] & PCI_COMMAND_MASTER)) {
virtio_set_disabled(vdev, true);
virtio_pci_stop_ioeventfd(proxy);
virtio_set_status(vdev, vdev->status & ~VIRTIO_CONFIG_S_DRIVER_OK);
} else {
virtio_set_disabled(vdev, false);
}
}
if (proxy->config_cap &&
ranges_overlap(address, len, proxy->config_cap + offsetof(struct virtio_pci_cfg_cap,
pci_cfg_data),
sizeof cfg->pci_cfg_data)) {
uint32_t off;
uint32_t len;
cfg = (void *)(proxy->pci_dev.config + proxy->config_cap);
off = le32_to_cpu(cfg->cap.offset);
len = le32_to_cpu(cfg->cap.length);
if (len == 1 || len == 2 || len == 4) {
assert(len <= sizeof cfg->pci_cfg_data);
virtio_address_space_write(proxy, off, cfg->pci_cfg_data, len);
}
}
}
static uint32_t virtio_read_config(PCIDevice *pci_dev,
uint32_t address, int len)
{
VirtIOPCIProxy *proxy = VIRTIO_PCI(pci_dev);
struct virtio_pci_cfg_cap *cfg;
if (proxy->config_cap &&
ranges_overlap(address, len, proxy->config_cap + offsetof(struct virtio_pci_cfg_cap,
pci_cfg_data),
sizeof cfg->pci_cfg_data)) {
uint32_t off;
uint32_t len;
cfg = (void *)(proxy->pci_dev.config + proxy->config_cap);
off = le32_to_cpu(cfg->cap.offset);
len = le32_to_cpu(cfg->cap.length);
if (len == 1 || len == 2 || len == 4) {
assert(len <= sizeof cfg->pci_cfg_data);
virtio_address_space_read(proxy, off, cfg->pci_cfg_data, len);
}
}
return pci_default_read_config(pci_dev, address, len);
}
static int kvm_virtio_pci_vq_vector_use(VirtIOPCIProxy *proxy,
unsigned int queue_no,
unsigned int vector)
{
VirtIOIRQFD *irqfd = &proxy->vector_irqfd[vector];
int ret;
if (irqfd->users == 0) {
ret = kvm_irqchip_add_msi_route(kvm_state, vector, &proxy->pci_dev);
if (ret < 0) {
return ret;
}
irqfd->virq = ret;
}
irqfd->users++;
return 0;
}
static void kvm_virtio_pci_vq_vector_release(VirtIOPCIProxy *proxy,
unsigned int vector)
{
VirtIOIRQFD *irqfd = &proxy->vector_irqfd[vector];
if (--irqfd->users == 0) {
kvm_irqchip_release_virq(kvm_state, irqfd->virq);
}
}
static int kvm_virtio_pci_irqfd_use(VirtIOPCIProxy *proxy,
unsigned int queue_no,
unsigned int vector)
{
VirtIOIRQFD *irqfd = &proxy->vector_irqfd[vector];
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
VirtQueue *vq = virtio_get_queue(vdev, queue_no);
EventNotifier *n = virtio_queue_get_guest_notifier(vq);
return kvm_irqchip_add_irqfd_notifier_gsi(kvm_state, n, NULL, irqfd->virq);
}
static void kvm_virtio_pci_irqfd_release(VirtIOPCIProxy *proxy,
unsigned int queue_no,
unsigned int vector)
{
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
VirtQueue *vq = virtio_get_queue(vdev, queue_no);
EventNotifier *n = virtio_queue_get_guest_notifier(vq);
VirtIOIRQFD *irqfd = &proxy->vector_irqfd[vector];
int ret;
ret = kvm_irqchip_remove_irqfd_notifier_gsi(kvm_state, n, irqfd->virq);
assert(ret == 0);
}
static int kvm_virtio_pci_vector_use(VirtIOPCIProxy *proxy, int nvqs)
{
PCIDevice *dev = &proxy->pci_dev;
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev);
unsigned int vector;
int ret, queue_no;
for (queue_no = 0; queue_no < nvqs; queue_no++) {
if (!virtio_queue_get_num(vdev, queue_no)) {
break;
}
vector = virtio_queue_vector(vdev, queue_no);
if (vector >= msix_nr_vectors_allocated(dev)) {
continue;
}
ret = kvm_virtio_pci_vq_vector_use(proxy, queue_no, vector);
if (ret < 0) {
goto undo;
}
/* If guest supports masking, set up irqfd now.
* Otherwise, delay until unmasked in the frontend.
*/
if (vdev->use_guest_notifier_mask && k->guest_notifier_mask) {
ret = kvm_virtio_pci_irqfd_use(proxy, queue_no, vector);
if (ret < 0) {
kvm_virtio_pci_vq_vector_release(proxy, vector);
goto undo;
}
}
}
return 0;
undo:
while (--queue_no >= 0) {
vector = virtio_queue_vector(vdev, queue_no);
if (vector >= msix_nr_vectors_allocated(dev)) {
continue;
}
if (vdev->use_guest_notifier_mask && k->guest_notifier_mask) {
kvm_virtio_pci_irqfd_release(proxy, queue_no, vector);
}
kvm_virtio_pci_vq_vector_release(proxy, vector);
}
return ret;
}
static void kvm_virtio_pci_vector_release(VirtIOPCIProxy *proxy, int nvqs)
{
PCIDevice *dev = &proxy->pci_dev;
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
unsigned int vector;
int queue_no;
VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev);
for (queue_no = 0; queue_no < nvqs; queue_no++) {
if (!virtio_queue_get_num(vdev, queue_no)) {
break;
}
vector = virtio_queue_vector(vdev, queue_no);
if (vector >= msix_nr_vectors_allocated(dev)) {
continue;
}
/* If guest supports masking, clean up irqfd now.
* Otherwise, it was cleaned when masked in the frontend.
*/
if (vdev->use_guest_notifier_mask && k->guest_notifier_mask) {
kvm_virtio_pci_irqfd_release(proxy, queue_no, vector);
}
kvm_virtio_pci_vq_vector_release(proxy, vector);
}
}
static int virtio_pci_vq_vector_unmask(VirtIOPCIProxy *proxy,
unsigned int queue_no,
unsigned int vector,
MSIMessage msg)
{
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev);
VirtQueue *vq = virtio_get_queue(vdev, queue_no);
EventNotifier *n = virtio_queue_get_guest_notifier(vq);
VirtIOIRQFD *irqfd;
int ret = 0;
if (proxy->vector_irqfd) {
irqfd = &proxy->vector_irqfd[vector];
if (irqfd->msg.data != msg.data || irqfd->msg.address != msg.address) {
ret = kvm_irqchip_update_msi_route(kvm_state, irqfd->virq, msg,
&proxy->pci_dev);
if (ret < 0) {
return ret;
}
kvm_irqchip_commit_routes(kvm_state);
}
}
/* If guest supports masking, irqfd is already setup, unmask it.
* Otherwise, set it up now.
*/
if (vdev->use_guest_notifier_mask && k->guest_notifier_mask) {
k->guest_notifier_mask(vdev, queue_no, false);
/* Test after unmasking to avoid losing events. */
if (k->guest_notifier_pending &&
k->guest_notifier_pending(vdev, queue_no)) {
event_notifier_set(n);
}
} else {
ret = kvm_virtio_pci_irqfd_use(proxy, queue_no, vector);
}
return ret;
}
static void virtio_pci_vq_vector_mask(VirtIOPCIProxy *proxy,
unsigned int queue_no,
unsigned int vector)
{
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev);
/* If guest supports masking, keep irqfd but mask it.
* Otherwise, clean it up now.
*/
if (vdev->use_guest_notifier_mask && k->guest_notifier_mask) {
k->guest_notifier_mask(vdev, queue_no, true);
} else {
kvm_virtio_pci_irqfd_release(proxy, queue_no, vector);
}
}
static int virtio_pci_vector_unmask(PCIDevice *dev, unsigned vector,
MSIMessage msg)
{
VirtIOPCIProxy *proxy = container_of(dev, VirtIOPCIProxy, pci_dev);
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
VirtQueue *vq = virtio_vector_first_queue(vdev, vector);
int ret, index, unmasked = 0;
while (vq) {
index = virtio_get_queue_index(vq);
if (!virtio_queue_get_num(vdev, index)) {
break;
}
if (index < proxy->nvqs_with_notifiers) {
ret = virtio_pci_vq_vector_unmask(proxy, index, vector, msg);
if (ret < 0) {
goto undo;
}
++unmasked;
}
vq = virtio_vector_next_queue(vq);
}
return 0;
undo:
vq = virtio_vector_first_queue(vdev, vector);
while (vq && unmasked >= 0) {
index = virtio_get_queue_index(vq);
if (index < proxy->nvqs_with_notifiers) {
virtio_pci_vq_vector_mask(proxy, index, vector);
--unmasked;
}
vq = virtio_vector_next_queue(vq);
}
return ret;
}
static void virtio_pci_vector_mask(PCIDevice *dev, unsigned vector)
{
VirtIOPCIProxy *proxy = container_of(dev, VirtIOPCIProxy, pci_dev);
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
VirtQueue *vq = virtio_vector_first_queue(vdev, vector);
int index;
while (vq) {
index = virtio_get_queue_index(vq);
if (!virtio_queue_get_num(vdev, index)) {
break;
}
if (index < proxy->nvqs_with_notifiers) {
virtio_pci_vq_vector_mask(proxy, index, vector);
}
vq = virtio_vector_next_queue(vq);
}
}
static void virtio_pci_vector_poll(PCIDevice *dev,
unsigned int vector_start,
unsigned int vector_end)
{
VirtIOPCIProxy *proxy = container_of(dev, VirtIOPCIProxy, pci_dev);
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev);
int queue_no;
unsigned int vector;
EventNotifier *notifier;
VirtQueue *vq;
for (queue_no = 0; queue_no < proxy->nvqs_with_notifiers; queue_no++) {
if (!virtio_queue_get_num(vdev, queue_no)) {
break;
}
vector = virtio_queue_vector(vdev, queue_no);
if (vector < vector_start || vector >= vector_end ||
!msix_is_masked(dev, vector)) {
continue;
}
vq = virtio_get_queue(vdev, queue_no);
notifier = virtio_queue_get_guest_notifier(vq);
if (k->guest_notifier_pending) {
if (k->guest_notifier_pending(vdev, queue_no)) {
msix_set_pending(dev, vector);
}
} else if (event_notifier_test_and_clear(notifier)) {
msix_set_pending(dev, vector);
}
}
}
static int virtio_pci_set_guest_notifier(DeviceState *d, int n, bool assign,
bool with_irqfd)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
VirtQueue *vq = virtio_get_queue(vdev, n);
EventNotifier *notifier = virtio_queue_get_guest_notifier(vq);
if (assign) {
int r = event_notifier_init(notifier, 0);
if (r < 0) {
return r;
}
virtio_queue_set_guest_notifier_fd_handler(vq, true, with_irqfd);
} else {
virtio_queue_set_guest_notifier_fd_handler(vq, false, with_irqfd);
event_notifier_cleanup(notifier);
}
if (!msix_enabled(&proxy->pci_dev) &&
vdev->use_guest_notifier_mask &&
vdc->guest_notifier_mask) {
vdc->guest_notifier_mask(vdev, n, !assign);
}
return 0;
}
static bool virtio_pci_query_guest_notifiers(DeviceState *d)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
return msix_enabled(&proxy->pci_dev);
}
static int virtio_pci_set_guest_notifiers(DeviceState *d, int nvqs, bool assign)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev);
int r, n;
bool with_irqfd = msix_enabled(&proxy->pci_dev) &&
kvm_msi_via_irqfd_enabled();
nvqs = MIN(nvqs, VIRTIO_QUEUE_MAX);
/* When deassigning, pass a consistent nvqs value
* to avoid leaking notifiers.
*/
assert(assign || nvqs == proxy->nvqs_with_notifiers);
proxy->nvqs_with_notifiers = nvqs;
/* Must unset vector notifier while guest notifier is still assigned */
if ((proxy->vector_irqfd || k->guest_notifier_mask) && !assign) {
msix_unset_vector_notifiers(&proxy->pci_dev);
if (proxy->vector_irqfd) {
kvm_virtio_pci_vector_release(proxy, nvqs);
g_free(proxy->vector_irqfd);
proxy->vector_irqfd = NULL;
}
}
for (n = 0; n < nvqs; n++) {
if (!virtio_queue_get_num(vdev, n)) {
break;
}
r = virtio_pci_set_guest_notifier(d, n, assign, with_irqfd);
if (r < 0) {
goto assign_error;
}
}
/* Must set vector notifier after guest notifier has been assigned */
if ((with_irqfd || k->guest_notifier_mask) && assign) {
if (with_irqfd) {
proxy->vector_irqfd =
g_malloc0(sizeof(*proxy->vector_irqfd) *
msix_nr_vectors_allocated(&proxy->pci_dev));
r = kvm_virtio_pci_vector_use(proxy, nvqs);
if (r < 0) {
goto assign_error;
}
}
r = msix_set_vector_notifiers(&proxy->pci_dev,
virtio_pci_vector_unmask,
virtio_pci_vector_mask,
virtio_pci_vector_poll);
if (r < 0) {
goto notifiers_error;
}
}
return 0;
notifiers_error:
if (with_irqfd) {
assert(assign);
kvm_virtio_pci_vector_release(proxy, nvqs);
}
assign_error:
/* We get here on assignment failure. Recover by undoing for VQs 0 .. n. */
assert(assign);
while (--n >= 0) {
virtio_pci_set_guest_notifier(d, n, !assign, with_irqfd);
}
return r;
}
static int virtio_pci_set_host_notifier_mr(DeviceState *d, int n,
MemoryRegion *mr, bool assign)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
int offset;
if (n >= VIRTIO_QUEUE_MAX || !virtio_pci_modern(proxy) ||
virtio_pci_queue_mem_mult(proxy) != memory_region_size(mr)) {
return -1;
}
if (assign) {
offset = virtio_pci_queue_mem_mult(proxy) * n;
memory_region_add_subregion_overlap(&proxy->notify.mr, offset, mr, 1);
} else {
memory_region_del_subregion(&proxy->notify.mr, mr);
}
return 0;
}
static void virtio_pci_vmstate_change(DeviceState *d, bool running)
{
VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
if (running) {
/* Old QEMU versions did not set bus master enable on status write.
* Detect DRIVER set and enable it.
*/
if ((proxy->flags & VIRTIO_PCI_FLAG_BUS_MASTER_BUG_MIGRATION) &&
(vdev->status & VIRTIO_CONFIG_S_DRIVER) &&
!(proxy->pci_dev.config[PCI_COMMAND] & PCI_COMMAND_MASTER)) {
pci_default_write_config(&proxy->pci_dev, PCI_COMMAND,
proxy->pci_dev.config[PCI_COMMAND] |
PCI_COMMAND_MASTER, 1);
}
virtio_pci_start_ioeventfd(proxy);
} else {
virtio_pci_stop_ioeventfd(proxy);
}
}
/*
* virtio-pci: This is the PCIDevice which has a virtio-pci-bus.
*/
static int virtio_pci_query_nvectors(DeviceState *d)
{
VirtIOPCIProxy *proxy = VIRTIO_PCI(d);
return proxy->nvectors;
}
static AddressSpace *virtio_pci_get_dma_as(DeviceState *d)
{
VirtIOPCIProxy *proxy = VIRTIO_PCI(d);
PCIDevice *dev = &proxy->pci_dev;
return pci_get_address_space(dev);
}
static bool virtio_pci_queue_enabled(DeviceState *d, int n)
{
VirtIOPCIProxy *proxy = VIRTIO_PCI(d);
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {
return proxy->vqs[n].enabled;
}
return virtio_queue_enabled_legacy(vdev, n);
}
static int virtio_pci_add_mem_cap(VirtIOPCIProxy *proxy,
struct virtio_pci_cap *cap)
{
PCIDevice *dev = &proxy->pci_dev;
int offset;
offset = pci_add_capability(dev, PCI_CAP_ID_VNDR, 0,
cap->cap_len, &error_abort);
assert(cap->cap_len >= sizeof *cap);
memcpy(dev->config + offset + PCI_CAP_FLAGS, &cap->cap_len,
cap->cap_len - PCI_CAP_FLAGS);
return offset;
}
static uint64_t virtio_pci_common_read(void *opaque, hwaddr addr,
unsigned size)
{
VirtIOPCIProxy *proxy = opaque;
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
uint32_t val = 0;
int i;
switch (addr) {
case VIRTIO_PCI_COMMON_DFSELECT:
val = proxy->dfselect;
break;
case VIRTIO_PCI_COMMON_DF:
if (proxy->dfselect <= 1) {
VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
val = (vdev->host_features & ~vdc->legacy_features) >>
(32 * proxy->dfselect);
}
break;
case VIRTIO_PCI_COMMON_GFSELECT:
val = proxy->gfselect;
break;
case VIRTIO_PCI_COMMON_GF:
if (proxy->gfselect < ARRAY_SIZE(proxy->guest_features)) {
val = proxy->guest_features[proxy->gfselect];
}
break;
case VIRTIO_PCI_COMMON_MSIX:
val = vdev->config_vector;
break;
case VIRTIO_PCI_COMMON_NUMQ:
for (i = 0; i < VIRTIO_QUEUE_MAX; ++i) {
if (virtio_queue_get_num(vdev, i)) {
val = i + 1;
}
}
break;
case VIRTIO_PCI_COMMON_STATUS:
val = vdev->status;
break;
case VIRTIO_PCI_COMMON_CFGGENERATION:
val = vdev->generation;
break;
case VIRTIO_PCI_COMMON_Q_SELECT:
val = vdev->queue_sel;
break;
case VIRTIO_PCI_COMMON_Q_SIZE:
val = virtio_queue_get_num(vdev, vdev->queue_sel);
break;
case VIRTIO_PCI_COMMON_Q_MSIX:
val = virtio_queue_vector(vdev, vdev->queue_sel);
break;
case VIRTIO_PCI_COMMON_Q_ENABLE:
val = proxy->vqs[vdev->queue_sel].enabled;
break;
case VIRTIO_PCI_COMMON_Q_NOFF:
/* Simply map queues in order */
val = vdev->queue_sel;
break;
case VIRTIO_PCI_COMMON_Q_DESCLO:
val = proxy->vqs[vdev->queue_sel].desc[0];
break;
case VIRTIO_PCI_COMMON_Q_DESCHI:
val = proxy->vqs[vdev->queue_sel].desc[1];
break;
case VIRTIO_PCI_COMMON_Q_AVAILLO:
val = proxy->vqs[vdev->queue_sel].avail[0];
break;
case VIRTIO_PCI_COMMON_Q_AVAILHI:
val = proxy->vqs[vdev->queue_sel].avail[1];
break;
case VIRTIO_PCI_COMMON_Q_USEDLO:
val = proxy->vqs[vdev->queue_sel].used[0];
break;
case VIRTIO_PCI_COMMON_Q_USEDHI:
val = proxy->vqs[vdev->queue_sel].used[1];
break;
default:
val = 0;
}
return val;
}
static void virtio_pci_common_write(void *opaque, hwaddr addr,
uint64_t val, unsigned size)
{
VirtIOPCIProxy *proxy = opaque;
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
switch (addr) {
case VIRTIO_PCI_COMMON_DFSELECT:
proxy->dfselect = val;
break;
case VIRTIO_PCI_COMMON_GFSELECT:
proxy->gfselect = val;
break;
case VIRTIO_PCI_COMMON_GF:
if (proxy->gfselect < ARRAY_SIZE(proxy->guest_features)) {
proxy->guest_features[proxy->gfselect] = val;
virtio_set_features(vdev,
(((uint64_t)proxy->guest_features[1]) << 32) |
proxy->guest_features[0]);
}
break;
case VIRTIO_PCI_COMMON_MSIX:
msix_vector_unuse(&proxy->pci_dev, vdev->config_vector);
/* Make it possible for guest to discover an error took place. */
if (msix_vector_use(&proxy->pci_dev, val) < 0) {
val = VIRTIO_NO_VECTOR;
}
vdev->config_vector = val;
break;
case VIRTIO_PCI_COMMON_STATUS:
if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) {
virtio_pci_stop_ioeventfd(proxy);
}
virtio_set_status(vdev, val & 0xFF);
if (val & VIRTIO_CONFIG_S_DRIVER_OK) {
virtio_pci_start_ioeventfd(proxy);
}
if (vdev->status == 0) {
virtio_pci_reset(DEVICE(proxy));
}
break;
case VIRTIO_PCI_COMMON_Q_SELECT:
if (val < VIRTIO_QUEUE_MAX) {
vdev->queue_sel = val;
}
break;
case VIRTIO_PCI_COMMON_Q_SIZE:
proxy->vqs[vdev->queue_sel].num = val;
virtio_queue_set_num(vdev, vdev->queue_sel,
proxy->vqs[vdev->queue_sel].num);
break;
case VIRTIO_PCI_COMMON_Q_MSIX:
msix_vector_unuse(&proxy->pci_dev,
virtio_queue_vector(vdev, vdev->queue_sel));
/* Make it possible for guest to discover an error took place. */
if (msix_vector_use(&proxy->pci_dev, val) < 0) {
val = VIRTIO_NO_VECTOR;
}
virtio_queue_set_vector(vdev, vdev->queue_sel, val);
break;
case VIRTIO_PCI_COMMON_Q_ENABLE:
if (val == 1) {
virtio_queue_set_num(vdev, vdev->queue_sel,
proxy->vqs[vdev->queue_sel].num);
virtio_queue_set_rings(vdev, vdev->queue_sel,
((uint64_t)proxy->vqs[vdev->queue_sel].desc[1]) << 32 |
proxy->vqs[vdev->queue_sel].desc[0],
((uint64_t)proxy->vqs[vdev->queue_sel].avail[1]) << 32 |
proxy->vqs[vdev->queue_sel].avail[0],
((uint64_t)proxy->vqs[vdev->queue_sel].used[1]) << 32 |
proxy->vqs[vdev->queue_sel].used[0]);
proxy->vqs[vdev->queue_sel].enabled = 1;
} else {
virtio_error(vdev, "wrong value for queue_enable %"PRIx64, val);
}
break;
case VIRTIO_PCI_COMMON_Q_DESCLO:
proxy->vqs[vdev->queue_sel].desc[0] = val;
break;
case VIRTIO_PCI_COMMON_Q_DESCHI:
proxy->vqs[vdev->queue_sel].desc[1] = val;
break;
case VIRTIO_PCI_COMMON_Q_AVAILLO:
proxy->vqs[vdev->queue_sel].avail[0] = val;
break;
case VIRTIO_PCI_COMMON_Q_AVAILHI:
proxy->vqs[vdev->queue_sel].avail[1] = val;
break;
case VIRTIO_PCI_COMMON_Q_USEDLO:
proxy->vqs[vdev->queue_sel].used[0] = val;
break;
case VIRTIO_PCI_COMMON_Q_USEDHI:
proxy->vqs[vdev->queue_sel].used[1] = val;
break;
default:
break;
}
}
static uint64_t virtio_pci_notify_read(void *opaque, hwaddr addr,
unsigned size)
{
return 0;
}
static void virtio_pci_notify_write(void *opaque, hwaddr addr,
uint64_t val, unsigned size)
{
VirtIOPCIProxy *proxy = opaque;
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
unsigned queue = addr / virtio_pci_queue_mem_mult(proxy);
if (vdev != NULL && queue < VIRTIO_QUEUE_MAX) {
virtio_queue_notify(vdev, queue);
}
}
static void virtio_pci_notify_write_pio(void *opaque, hwaddr addr,
uint64_t val, unsigned size)
{
VirtIOPCIProxy *proxy = opaque;
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
unsigned queue = val;
if (vdev != NULL && queue < VIRTIO_QUEUE_MAX) {
virtio_queue_notify(vdev, queue);
}
}
static uint64_t virtio_pci_isr_read(void *opaque, hwaddr addr,
unsigned size)
{
VirtIOPCIProxy *proxy = opaque;
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
uint64_t val = qatomic_xchg(&vdev->isr, 0);
pci_irq_deassert(&proxy->pci_dev);
return val;
}
static void virtio_pci_isr_write(void *opaque, hwaddr addr,
uint64_t val, unsigned size)
{
}
static uint64_t virtio_pci_device_read(void *opaque, hwaddr addr,
unsigned size)
{
VirtIOPCIProxy *proxy = opaque;
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
uint64_t val = 0;
if (vdev == NULL) {
return val;
}
switch (size) {
case 1:
val = virtio_config_modern_readb(vdev, addr);
break;
case 2:
val = virtio_config_modern_readw(vdev, addr);
break;
case 4:
val = virtio_config_modern_readl(vdev, addr);
break;
}
return val;
}
static void virtio_pci_device_write(void *opaque, hwaddr addr,
uint64_t val, unsigned size)
{
VirtIOPCIProxy *proxy = opaque;
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
if (vdev == NULL) {
return;
}
switch (size) {
case 1:
virtio_config_modern_writeb(vdev, addr, val);
break;
case 2:
virtio_config_modern_writew(vdev, addr, val);
break;
case 4:
virtio_config_modern_writel(vdev, addr, val);
break;
}
}
static void virtio_pci_modern_regions_init(VirtIOPCIProxy *proxy,
const char *vdev_name)
{
static const MemoryRegionOps common_ops = {
.read = virtio_pci_common_read,
.write = virtio_pci_common_write,
.impl = {
.min_access_size = 1,
.max_access_size = 4,
},
.endianness = DEVICE_LITTLE_ENDIAN,
};
static const MemoryRegionOps isr_ops = {
.read = virtio_pci_isr_read,
.write = virtio_pci_isr_write,
.impl = {
.min_access_size = 1,
.max_access_size = 4,
},
.endianness = DEVICE_LITTLE_ENDIAN,
};
static const MemoryRegionOps device_ops = {
.read = virtio_pci_device_read,
.write = virtio_pci_device_write,
.impl = {
.min_access_size = 1,
.max_access_size = 4,
},
.endianness = DEVICE_LITTLE_ENDIAN,
};
static const MemoryRegionOps notify_ops = {
.read = virtio_pci_notify_read,
.write = virtio_pci_notify_write,
.impl = {
.min_access_size = 1,
.max_access_size = 4,
},
.endianness = DEVICE_LITTLE_ENDIAN,
};
static const MemoryRegionOps notify_pio_ops = {
.read = virtio_pci_notify_read,
.write = virtio_pci_notify_write_pio,
.impl = {
.min_access_size = 1,
.max_access_size = 4,
},
.endianness = DEVICE_LITTLE_ENDIAN,
};
g_autoptr(GString) name = g_string_new(NULL);
g_string_printf(name, "virtio-pci-common-%s", vdev_name);
memory_region_init_io(&proxy->common.mr, OBJECT(proxy),
&common_ops,
proxy,
name->str,
proxy->common.size);
g_string_printf(name, "virtio-pci-isr-%s", vdev_name);
memory_region_init_io(&proxy->isr.mr, OBJECT(proxy),
&isr_ops,
proxy,
name->str,
proxy->isr.size);
g_string_printf(name, "virtio-pci-device-%s", vdev_name);
memory_region_init_io(&proxy->device.mr, OBJECT(proxy),
&device_ops,
proxy,
name->str,
proxy->device.size);
g_string_printf(name, "virtio-pci-notify-%s", vdev_name);
memory_region_init_io(&proxy->notify.mr, OBJECT(proxy),
¬ify_ops,
proxy,
name->str,
proxy->notify.size);
g_string_printf(name, "virtio-pci-notify-pio-%s", vdev_name);
memory_region_init_io(&proxy->notify_pio.mr, OBJECT(proxy),
¬ify_pio_ops,
proxy,
name->str,
proxy->notify_pio.size);
}
static void virtio_pci_modern_region_map(VirtIOPCIProxy *proxy,
VirtIOPCIRegion *region,
struct virtio_pci_cap *cap,
MemoryRegion *mr,
uint8_t bar)
{
memory_region_add_subregion(mr, region->offset, ®ion->mr);
cap->cfg_type = region->type;
cap->bar = bar;
cap->offset = cpu_to_le32(region->offset);
cap->length = cpu_to_le32(region->size);
virtio_pci_add_mem_cap(proxy, cap);
}
static void virtio_pci_modern_mem_region_map(VirtIOPCIProxy *proxy,
VirtIOPCIRegion *region,
struct virtio_pci_cap *cap)
{
virtio_pci_modern_region_map(proxy, region, cap,
&proxy->modern_bar, proxy->modern_mem_bar_idx);
}
static void virtio_pci_modern_io_region_map(VirtIOPCIProxy *proxy,
VirtIOPCIRegion *region,
struct virtio_pci_cap *cap)
{
virtio_pci_modern_region_map(proxy, region, cap,
&proxy->io_bar, proxy->modern_io_bar_idx);
}
static void virtio_pci_modern_mem_region_unmap(VirtIOPCIProxy *proxy,
VirtIOPCIRegion *region)
{
memory_region_del_subregion(&proxy->modern_bar,
®ion->mr);
}
static void virtio_pci_modern_io_region_unmap(VirtIOPCIProxy *proxy,
VirtIOPCIRegion *region)
{
memory_region_del_subregion(&proxy->io_bar,
®ion->mr);
}
static void virtio_pci_pre_plugged(DeviceState *d, Error **errp)
{
VirtIOPCIProxy *proxy = VIRTIO_PCI(d);
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
if (virtio_pci_modern(proxy)) {
virtio_add_feature(&vdev->host_features, VIRTIO_F_VERSION_1);
}
virtio_add_feature(&vdev->host_features, VIRTIO_F_BAD_FEATURE);
}
/* This is called by virtio-bus just after the device is plugged. */
static void virtio_pci_device_plugged(DeviceState *d, Error **errp)
{
VirtIOPCIProxy *proxy = VIRTIO_PCI(d);
VirtioBusState *bus = &proxy->bus;
bool legacy = virtio_pci_legacy(proxy);
bool modern;
bool modern_pio = proxy->flags & VIRTIO_PCI_FLAG_MODERN_PIO_NOTIFY;
uint8_t *config;
uint32_t size;
VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
/*
* Virtio capabilities present without
* VIRTIO_F_VERSION_1 confuses guests
*/
if (!proxy->ignore_backend_features &&
!virtio_has_feature(vdev->host_features, VIRTIO_F_VERSION_1)) {
virtio_pci_disable_modern(proxy);
if (!legacy) {
error_setg(errp, "Device doesn't support modern mode, and legacy"
" mode is disabled");
error_append_hint(errp, "Set disable-legacy to off\n");
return;
}
}
modern = virtio_pci_modern(proxy);
config = proxy->pci_dev.config;
if (proxy->class_code) {
pci_config_set_class(config, proxy->class_code);
}
if (legacy) {
if (!virtio_legacy_allowed(vdev)) {
/*
* To avoid migration issues, we allow legacy mode when legacy
* check is disabled in the old machine types (< 5.1).
*/
if (virtio_legacy_check_disabled(vdev)) {
warn_report("device is modern-only, but for backward "
"compatibility legacy is allowed");
} else {
error_setg(errp,
"device is modern-only, use disable-legacy=on");
return;
}
}
if (virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM)) {
error_setg(errp, "VIRTIO_F_IOMMU_PLATFORM was supported by"
" neither legacy nor transitional device");
return ;
}
/*
* Legacy and transitional devices use specific subsystem IDs.
* Note that the subsystem vendor ID (config + PCI_SUBSYSTEM_VENDOR_ID)
* is set to PCI_SUBVENDOR_ID_REDHAT_QUMRANET by default.
*/
pci_set_word(config + PCI_SUBSYSTEM_ID, virtio_bus_get_vdev_id(bus));
} else {
/* pure virtio-1.0 */
pci_set_word(config + PCI_VENDOR_ID,
PCI_VENDOR_ID_REDHAT_QUMRANET);
pci_set_word(config + PCI_DEVICE_ID,
0x1040 + virtio_bus_get_vdev_id(bus));
pci_config_set_revision(config, 1);
}
config[PCI_INTERRUPT_PIN] = 1;
if (modern) {
struct virtio_pci_cap cap = {
.cap_len = sizeof cap,
};
struct virtio_pci_notify_cap notify = {
.cap.cap_len = sizeof notify,
.notify_off_multiplier =
cpu_to_le32(virtio_pci_queue_mem_mult(proxy)),
};
struct virtio_pci_cfg_cap cfg = {
.cap.cap_len = sizeof cfg,
.cap.cfg_type = VIRTIO_PCI_CAP_PCI_CFG,
};
struct virtio_pci_notify_cap notify_pio = {
.cap.cap_len = sizeof notify,
.notify_off_multiplier = cpu_to_le32(0x0),
};
struct virtio_pci_cfg_cap *cfg_mask;
virtio_pci_modern_regions_init(proxy, vdev->name);
virtio_pci_modern_mem_region_map(proxy, &proxy->common, &cap);
virtio_pci_modern_mem_region_map(proxy, &proxy->isr, &cap);
virtio_pci_modern_mem_region_map(proxy, &proxy->device, &cap);
virtio_pci_modern_mem_region_map(proxy, &proxy->notify, ¬ify.cap);
if (modern_pio) {
memory_region_init(&proxy->io_bar, OBJECT(proxy),
"virtio-pci-io", 0x4);
pci_register_bar(&proxy->pci_dev, proxy->modern_io_bar_idx,
PCI_BASE_ADDRESS_SPACE_IO, &proxy->io_bar);
virtio_pci_modern_io_region_map(proxy, &proxy->notify_pio,
¬ify_pio.cap);
}
pci_register_bar(&proxy->pci_dev, proxy->modern_mem_bar_idx,
PCI_BASE_ADDRESS_SPACE_MEMORY |
PCI_BASE_ADDRESS_MEM_PREFETCH |
PCI_BASE_ADDRESS_MEM_TYPE_64,
&proxy->modern_bar);
proxy->config_cap = virtio_pci_add_mem_cap(proxy, &cfg.cap);
cfg_mask = (void *)(proxy->pci_dev.wmask + proxy->config_cap);
pci_set_byte(&cfg_mask->cap.bar, ~0x0);
pci_set_long((uint8_t *)&cfg_mask->cap.offset, ~0x0);
pci_set_long((uint8_t *)&cfg_mask->cap.length, ~0x0);
pci_set_long(cfg_mask->pci_cfg_data, ~0x0);
}
if (proxy->nvectors) {
int err = msix_init_exclusive_bar(&proxy->pci_dev, proxy->nvectors,
proxy->msix_bar_idx, NULL);
if (err) {
/* Notice when a system that supports MSIx can't initialize it */
if (err != -ENOTSUP) {
warn_report("unable to init msix vectors to %" PRIu32,
proxy->nvectors);
}
proxy->nvectors = 0;
}
}
proxy->pci_dev.config_write = virtio_write_config;
proxy->pci_dev.config_read = virtio_read_config;
if (legacy) {
size = VIRTIO_PCI_REGION_SIZE(&proxy->pci_dev)
+ virtio_bus_get_vdev_config_len(bus);
size = pow2ceil(size);
memory_region_init_io(&proxy->bar, OBJECT(proxy),
&virtio_pci_config_ops,
proxy, "virtio-pci", size);
pci_register_bar(&proxy->pci_dev, proxy->legacy_io_bar_idx,
PCI_BASE_ADDRESS_SPACE_IO, &proxy->bar);
}
}
static void virtio_pci_device_unplugged(DeviceState *d)
{
VirtIOPCIProxy *proxy = VIRTIO_PCI(d);
bool modern = virtio_pci_modern(proxy);
bool modern_pio = proxy->flags & VIRTIO_PCI_FLAG_MODERN_PIO_NOTIFY;
virtio_pci_stop_ioeventfd(proxy);
if (modern) {
virtio_pci_modern_mem_region_unmap(proxy, &proxy->common);
virtio_pci_modern_mem_region_unmap(proxy, &proxy->isr);
virtio_pci_modern_mem_region_unmap(proxy, &proxy->device);
virtio_pci_modern_mem_region_unmap(proxy, &proxy->notify);
if (modern_pio) {
virtio_pci_modern_io_region_unmap(proxy, &proxy->notify_pio);
}
}
}
static void virtio_pci_realize(PCIDevice *pci_dev, Error **errp)
{
VirtIOPCIProxy *proxy = VIRTIO_PCI(pci_dev);
VirtioPCIClass *k = VIRTIO_PCI_GET_CLASS(pci_dev);
bool pcie_port = pci_bus_is_express(pci_get_bus(pci_dev)) &&
!pci_bus_is_root(pci_get_bus(pci_dev));
if (kvm_enabled() && !kvm_has_many_ioeventfds()) {
proxy->flags &= ~VIRTIO_PCI_FLAG_USE_IOEVENTFD;
}
/*
* virtio pci bar layout used by default.
* subclasses can re-arrange things if needed.
*
* region 0 -- virtio legacy io bar
* region 1 -- msi-x bar
* region 2 -- virtio modern io bar (off by default)
* region 4+5 -- virtio modern memory (64bit) bar
*
*/
proxy->legacy_io_bar_idx = 0;
proxy->msix_bar_idx = 1;
proxy->modern_io_bar_idx = 2;
proxy->modern_mem_bar_idx = 4;
proxy->common.offset = 0x0;
proxy->common.size = 0x1000;
proxy->common.type = VIRTIO_PCI_CAP_COMMON_CFG;
proxy->isr.offset = 0x1000;
proxy->isr.size = 0x1000;
proxy->isr.type = VIRTIO_PCI_CAP_ISR_CFG;
proxy->device.offset = 0x2000;
proxy->device.size = 0x1000;
proxy->device.type = VIRTIO_PCI_CAP_DEVICE_CFG;
proxy->notify.offset = 0x3000;
proxy->notify.size = virtio_pci_queue_mem_mult(proxy) * VIRTIO_QUEUE_MAX;
proxy->notify.type = VIRTIO_PCI_CAP_NOTIFY_CFG;
proxy->notify_pio.offset = 0x0;
proxy->notify_pio.size = 0x4;
proxy->notify_pio.type = VIRTIO_PCI_CAP_NOTIFY_CFG;
/* subclasses can enforce modern, so do this unconditionally */
memory_region_init(&proxy->modern_bar, OBJECT(proxy), "virtio-pci",
/* PCI BAR regions must be powers of 2 */
pow2ceil(proxy->notify.offset + proxy->notify.size));
if (proxy->disable_legacy == ON_OFF_AUTO_AUTO) {
proxy->disable_legacy = pcie_port ? ON_OFF_AUTO_ON : ON_OFF_AUTO_OFF;
}
if (!virtio_pci_modern(proxy) && !virtio_pci_legacy(proxy)) {
error_setg(errp, "device cannot work as neither modern nor legacy mode"
" is enabled");
error_append_hint(errp, "Set either disable-modern or disable-legacy"
" to off\n");
return;
}
if (pcie_port && pci_is_express(pci_dev)) {
int pos;
uint16_t last_pcie_cap_offset = PCI_CONFIG_SPACE_SIZE;
pos = pcie_endpoint_cap_init(pci_dev, 0);
assert(pos > 0);
pos = pci_add_capability(pci_dev, PCI_CAP_ID_PM, 0,
PCI_PM_SIZEOF, errp);
if (pos < 0) {
return;
}
pci_dev->exp.pm_cap = pos;
/*
* Indicates that this function complies with revision 1.2 of the
* PCI Power Management Interface Specification.
*/
pci_set_word(pci_dev->config + pos + PCI_PM_PMC, 0x3);
if (proxy->flags & VIRTIO_PCI_FLAG_AER) {
pcie_aer_init(pci_dev, PCI_ERR_VER, last_pcie_cap_offset,
PCI_ERR_SIZEOF, NULL);
last_pcie_cap_offset += PCI_ERR_SIZEOF;
}
if (proxy->flags & VIRTIO_PCI_FLAG_INIT_DEVERR) {
/* Init error enabling flags */
pcie_cap_deverr_init(pci_dev);
}
if (proxy->flags & VIRTIO_PCI_FLAG_INIT_LNKCTL) {
/* Init Link Control Register */
pcie_cap_lnkctl_init(pci_dev);
}
if (proxy->flags & VIRTIO_PCI_FLAG_INIT_PM) {
/* Init Power Management Control Register */
pci_set_word(pci_dev->wmask + pos + PCI_PM_CTRL,
PCI_PM_CTRL_STATE_MASK);
}
if (proxy->flags & VIRTIO_PCI_FLAG_ATS) {
pcie_ats_init(pci_dev, last_pcie_cap_offset);
last_pcie_cap_offset += PCI_EXT_CAP_ATS_SIZEOF;
}
if (proxy->flags & VIRTIO_PCI_FLAG_INIT_FLR) {
/* Set Function Level Reset capability bit */
pcie_cap_flr_init(pci_dev);
}
} else {
/*
* make future invocations of pci_is_express() return false
* and pci_config_size() return PCI_CONFIG_SPACE_SIZE.
*/
pci_dev->cap_present &= ~QEMU_PCI_CAP_EXPRESS;
}
virtio_pci_bus_new(&proxy->bus, sizeof(proxy->bus), proxy);
if (k->realize) {
k->realize(proxy, errp);
}
}
static void virtio_pci_exit(PCIDevice *pci_dev)
{
VirtIOPCIProxy *proxy = VIRTIO_PCI(pci_dev);
bool pcie_port = pci_bus_is_express(pci_get_bus(pci_dev)) &&
!pci_bus_is_root(pci_get_bus(pci_dev));
msix_uninit_exclusive_bar(pci_dev);
if (proxy->flags & VIRTIO_PCI_FLAG_AER && pcie_port &&
pci_is_express(pci_dev)) {
pcie_aer_exit(pci_dev);
}
}
static void virtio_pci_reset(DeviceState *qdev)
{
VirtIOPCIProxy *proxy = VIRTIO_PCI(qdev);
VirtioBusState *bus = VIRTIO_BUS(&proxy->bus);
PCIDevice *dev = PCI_DEVICE(qdev);
int i;
virtio_pci_stop_ioeventfd(proxy);
virtio_bus_reset(bus);
msix_unuse_all_vectors(&proxy->pci_dev);
for (i = 0; i < VIRTIO_QUEUE_MAX; i++) {
proxy->vqs[i].enabled = 0;
proxy->vqs[i].num = 0;
proxy->vqs[i].desc[0] = proxy->vqs[i].desc[1] = 0;
proxy->vqs[i].avail[0] = proxy->vqs[i].avail[1] = 0;
proxy->vqs[i].used[0] = proxy->vqs[i].used[1] = 0;
}
if (pci_is_express(dev)) {
pcie_cap_deverr_reset(dev);
pcie_cap_lnkctl_reset(dev);
pci_set_word(dev->config + dev->exp.pm_cap + PCI_PM_CTRL, 0);
}
}
static Property virtio_pci_properties[] = {
DEFINE_PROP_BIT("virtio-pci-bus-master-bug-migration", VirtIOPCIProxy, flags,
VIRTIO_PCI_FLAG_BUS_MASTER_BUG_MIGRATION_BIT, false),
DEFINE_PROP_BIT("migrate-extra", VirtIOPCIProxy, flags,
VIRTIO_PCI_FLAG_MIGRATE_EXTRA_BIT, true),
DEFINE_PROP_BIT("modern-pio-notify", VirtIOPCIProxy, flags,
VIRTIO_PCI_FLAG_MODERN_PIO_NOTIFY_BIT, false),
DEFINE_PROP_BIT("x-disable-pcie", VirtIOPCIProxy, flags,
VIRTIO_PCI_FLAG_DISABLE_PCIE_BIT, false),
DEFINE_PROP_BIT("page-per-vq", VirtIOPCIProxy, flags,
VIRTIO_PCI_FLAG_PAGE_PER_VQ_BIT, false),
DEFINE_PROP_BOOL("x-ignore-backend-features", VirtIOPCIProxy,
ignore_backend_features, false),
DEFINE_PROP_BIT("ats", VirtIOPCIProxy, flags,
VIRTIO_PCI_FLAG_ATS_BIT, false),
DEFINE_PROP_BIT("x-pcie-deverr-init", VirtIOPCIProxy, flags,
VIRTIO_PCI_FLAG_INIT_DEVERR_BIT, true),
DEFINE_PROP_BIT("x-pcie-lnkctl-init", VirtIOPCIProxy, flags,
VIRTIO_PCI_FLAG_INIT_LNKCTL_BIT, true),
DEFINE_PROP_BIT("x-pcie-pm-init", VirtIOPCIProxy, flags,
VIRTIO_PCI_FLAG_INIT_PM_BIT, true),
DEFINE_PROP_BIT("x-pcie-flr-init", VirtIOPCIProxy, flags,
VIRTIO_PCI_FLAG_INIT_FLR_BIT, true),
DEFINE_PROP_BIT("aer", VirtIOPCIProxy, flags,
VIRTIO_PCI_FLAG_AER_BIT, false),
DEFINE_PROP_END_OF_LIST(),
};
static void virtio_pci_dc_realize(DeviceState *qdev, Error **errp)
{
VirtioPCIClass *vpciklass = VIRTIO_PCI_GET_CLASS(qdev);
VirtIOPCIProxy *proxy = VIRTIO_PCI(qdev);
PCIDevice *pci_dev = &proxy->pci_dev;
if (!(proxy->flags & VIRTIO_PCI_FLAG_DISABLE_PCIE) &&
virtio_pci_modern(proxy)) {
pci_dev->cap_present |= QEMU_PCI_CAP_EXPRESS;
}
vpciklass->parent_dc_realize(qdev, errp);
}
static void virtio_pci_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
VirtioPCIClass *vpciklass = VIRTIO_PCI_CLASS(klass);
device_class_set_props(dc, virtio_pci_properties);
k->realize = virtio_pci_realize;
k->exit = virtio_pci_exit;
k->vendor_id = PCI_VENDOR_ID_REDHAT_QUMRANET;
k->revision = VIRTIO_PCI_ABI_VERSION;
k->class_id = PCI_CLASS_OTHERS;
device_class_set_parent_realize(dc, virtio_pci_dc_realize,
&vpciklass->parent_dc_realize);
dc->reset = virtio_pci_reset;
}
static const TypeInfo virtio_pci_info = {
.name = TYPE_VIRTIO_PCI,
.parent = TYPE_PCI_DEVICE,
.instance_size = sizeof(VirtIOPCIProxy),
.class_init = virtio_pci_class_init,
.class_size = sizeof(VirtioPCIClass),
.abstract = true,
};
static Property virtio_pci_generic_properties[] = {
DEFINE_PROP_ON_OFF_AUTO("disable-legacy", VirtIOPCIProxy, disable_legacy,
ON_OFF_AUTO_AUTO),
DEFINE_PROP_BOOL("disable-modern", VirtIOPCIProxy, disable_modern, false),
DEFINE_PROP_END_OF_LIST(),
};
static void virtio_pci_base_class_init(ObjectClass *klass, void *data)
{
const VirtioPCIDeviceTypeInfo *t = data;
if (t->class_init) {
t->class_init(klass, NULL);
}
}
static void virtio_pci_generic_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
device_class_set_props(dc, virtio_pci_generic_properties);
}
static void virtio_pci_transitional_instance_init(Object *obj)
{
VirtIOPCIProxy *proxy = VIRTIO_PCI(obj);
proxy->disable_legacy = ON_OFF_AUTO_OFF;
proxy->disable_modern = false;
}
static void virtio_pci_non_transitional_instance_init(Object *obj)
{
VirtIOPCIProxy *proxy = VIRTIO_PCI(obj);
proxy->disable_legacy = ON_OFF_AUTO_ON;
proxy->disable_modern = false;
}
void virtio_pci_types_register(const VirtioPCIDeviceTypeInfo *t)
{
char *base_name = NULL;
TypeInfo base_type_info = {
.name = t->base_name,
.parent = t->parent ? t->parent : TYPE_VIRTIO_PCI,
.instance_size = t->instance_size,
.instance_init = t->instance_init,
.class_size = t->class_size,
.abstract = true,
.interfaces = t->interfaces,
};
TypeInfo generic_type_info = {
.name = t->generic_name,
.parent = base_type_info.name,
.class_init = virtio_pci_generic_class_init,
.interfaces = (InterfaceInfo[]) {
{ INTERFACE_PCIE_DEVICE },
{ INTERFACE_CONVENTIONAL_PCI_DEVICE },
{ }
},
};
if (!base_type_info.name) {
/* No base type -> register a single generic device type */
/* use intermediate %s-base-type to add generic device props */
base_name = g_strdup_printf("%s-base-type", t->generic_name);
base_type_info.name = base_name;
base_type_info.class_init = virtio_pci_generic_class_init;
generic_type_info.parent = base_name;
generic_type_info.class_init = virtio_pci_base_class_init;
generic_type_info.class_data = (void *)t;
assert(!t->non_transitional_name);
assert(!t->transitional_name);
} else {
base_type_info.class_init = virtio_pci_base_class_init;
base_type_info.class_data = (void *)t;
}
type_register(&base_type_info);
if (generic_type_info.name) {
type_register(&generic_type_info);
}
if (t->non_transitional_name) {
const TypeInfo non_transitional_type_info = {
.name = t->non_transitional_name,
.parent = base_type_info.name,
.instance_init = virtio_pci_non_transitional_instance_init,
.interfaces = (InterfaceInfo[]) {
{ INTERFACE_PCIE_DEVICE },
{ INTERFACE_CONVENTIONAL_PCI_DEVICE },
{ }
},
};
type_register(&non_transitional_type_info);
}
if (t->transitional_name) {
const TypeInfo transitional_type_info = {
.name = t->transitional_name,
.parent = base_type_info.name,
.instance_init = virtio_pci_transitional_instance_init,
.interfaces = (InterfaceInfo[]) {
/*
* Transitional virtio devices work only as Conventional PCI
* devices because they require PIO ports.
*/
{ INTERFACE_CONVENTIONAL_PCI_DEVICE },
{ }
},
};
type_register(&transitional_type_info);
}
g_free(base_name);
}
unsigned virtio_pci_optimal_num_queues(unsigned fixed_queues)
{
/*
* 1:1 vq to vCPU mapping is ideal because the same vCPU that submitted
* virtqueue buffers can handle their completion. When a different vCPU
* handles completion it may need to IPI the vCPU that submitted the
* request and this adds overhead.
*
* Virtqueues consume guest RAM and MSI-X vectors. This is wasteful in
* guests with very many vCPUs and a device that is only used by a few
* vCPUs. Unfortunately optimizing that case requires manual pinning inside
* the guest, so those users might as well manually set the number of
* queues. There is no upper limit that can be applied automatically and
* doing so arbitrarily would result in a sudden performance drop once the
* threshold number of vCPUs is exceeded.
*/
unsigned num_queues = current_machine->smp.cpus;
/*
* The maximum number of MSI-X vectors is PCI_MSIX_FLAGS_QSIZE + 1, but the
* config change interrupt and the fixed virtqueues must be taken into
* account too.
*/
num_queues = MIN(num_queues, PCI_MSIX_FLAGS_QSIZE - fixed_queues);
/*
* There is a limit to how many virtqueues a device can have.
*/
return MIN(num_queues, VIRTIO_QUEUE_MAX - fixed_queues);
}
/* virtio-pci-bus */
static void virtio_pci_bus_new(VirtioBusState *bus, size_t bus_size,
VirtIOPCIProxy *dev)
{
DeviceState *qdev = DEVICE(dev);
char virtio_bus_name[] = "virtio-bus";
qbus_create_inplace(bus, bus_size, TYPE_VIRTIO_PCI_BUS, qdev,
virtio_bus_name);
}
static void virtio_pci_bus_class_init(ObjectClass *klass, void *data)
{
BusClass *bus_class = BUS_CLASS(klass);
VirtioBusClass *k = VIRTIO_BUS_CLASS(klass);
bus_class->max_dev = 1;
k->notify = virtio_pci_notify;
k->save_config = virtio_pci_save_config;
k->load_config = virtio_pci_load_config;
k->save_queue = virtio_pci_save_queue;
k->load_queue = virtio_pci_load_queue;
k->save_extra_state = virtio_pci_save_extra_state;
k->load_extra_state = virtio_pci_load_extra_state;
k->has_extra_state = virtio_pci_has_extra_state;
k->query_guest_notifiers = virtio_pci_query_guest_notifiers;
k->set_guest_notifiers = virtio_pci_set_guest_notifiers;
k->set_host_notifier_mr = virtio_pci_set_host_notifier_mr;
k->vmstate_change = virtio_pci_vmstate_change;
k->pre_plugged = virtio_pci_pre_plugged;
k->device_plugged = virtio_pci_device_plugged;
k->device_unplugged = virtio_pci_device_unplugged;
k->query_nvectors = virtio_pci_query_nvectors;
k->ioeventfd_enabled = virtio_pci_ioeventfd_enabled;
k->ioeventfd_assign = virtio_pci_ioeventfd_assign;
k->get_dma_as = virtio_pci_get_dma_as;
k->queue_enabled = virtio_pci_queue_enabled;
}
static const TypeInfo virtio_pci_bus_info = {
.name = TYPE_VIRTIO_PCI_BUS,
.parent = TYPE_VIRTIO_BUS,
.instance_size = sizeof(VirtioPCIBusState),
.class_size = sizeof(VirtioPCIBusClass),
.class_init = virtio_pci_bus_class_init,
};
static void virtio_pci_register_types(void)
{
/* Base types: */
type_register_static(&virtio_pci_bus_info);
type_register_static(&virtio_pci_info);
}
type_init(virtio_pci_register_types)