virtio: convert to use DMA api

Currently, all virtio devices bypass IOMMU completely. This is because
address_space_memory is assumed and used during DMA emulation. This
patch converts the virtio core API to use DMA API. This idea is

- introducing a new transport specific helper to query the dma address
  space. (only pci version is implemented).
- query and use this address space during virtio device guest memory
  accessing when iommu platform (VIRTIO_F_IOMMU_PLATFORM) was enabled
  for this device.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Amit Shah <amit.shah@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-block@nongnu.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
stable-2.9
Jason Wang 2016-12-30 18:09:10 +08:00 committed by Michael S. Tsirkin
parent a08aaff811
commit 8607f5c307
9 changed files with 93 additions and 36 deletions

View File

@ -863,7 +863,7 @@ static int virtio_blk_load_device(VirtIODevice *vdev, QEMUFile *f,
}
}
req = qemu_get_virtqueue_element(f, sizeof(VirtIOBlockReq));
req = qemu_get_virtqueue_element(vdev, f, sizeof(VirtIOBlockReq));
virtio_blk_init_request(s, virtio_get_queue(vdev, vq_idx), req);
req->next = s->rq;
s->rq = req;

View File

@ -732,6 +732,7 @@ static void virtio_serial_post_load_timer_cb(void *opaque)
static int fetch_active_ports_list(QEMUFile *f,
VirtIOSerial *s, uint32_t nr_active_ports)
{
VirtIODevice *vdev = VIRTIO_DEVICE(s);
uint32_t i;
s->post_load = g_malloc0(sizeof(*s->post_load));
@ -765,7 +766,7 @@ static int fetch_active_ports_list(QEMUFile *f,
qemu_get_be64s(f, &port->iov_offset);
port->elem =
qemu_get_virtqueue_element(f, sizeof(VirtQueueElement));
qemu_get_virtqueue_element(vdev, f, sizeof(VirtQueueElement));
/*
* Port was throttled on source machine. Let's

View File

@ -198,12 +198,14 @@ static void *virtio_scsi_load_request(QEMUFile *f, SCSIRequest *sreq)
SCSIBus *bus = sreq->bus;
VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus);
VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
VirtIODevice *vdev = VIRTIO_DEVICE(s);
VirtIOSCSIReq *req;
uint32_t n;
qemu_get_be32s(f, &n);
assert(n < vs->conf.num_queues);
req = qemu_get_virtqueue_element(f, sizeof(VirtIOSCSIReq) + vs->cdb_size);
req = qemu_get_virtqueue_element(vdev, f,
sizeof(VirtIOSCSIReq) + vs->cdb_size);
virtio_scsi_init_req(s, vs->cmd_vqs[n], req);
if (virtio_scsi_parse_req(req, sizeof(VirtIOSCSICmdReq) + vs->cdb_size,

View File

@ -28,6 +28,7 @@
#include "hw/qdev.h"
#include "hw/virtio/virtio-bus.h"
#include "hw/virtio/virtio.h"
#include "exec/address-spaces.h"
/* #define DEBUG_VIRTIO_BUS */
@ -61,6 +62,13 @@ void virtio_bus_device_plugged(VirtIODevice *vdev, Error **errp)
if (klass->device_plugged != NULL) {
klass->device_plugged(qbus->parent, errp);
}
if (klass->get_dma_as != NULL &&
virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM)) {
vdev->dma_as = klass->get_dma_as(qbus->parent);
} else {
vdev->dma_as = &address_space_memory;
}
}
/* Reset the virtio_bus */

View File

@ -1144,6 +1144,14 @@ static int virtio_pci_query_nvectors(DeviceState *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 int virtio_pci_add_mem_cap(VirtIOPCIProxy *proxy,
struct virtio_pci_cap *cap)
{
@ -1601,6 +1609,11 @@ static void virtio_pci_device_plugged(DeviceState *d, Error **errp)
}
if (legacy) {
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 */
pci_set_word(config + PCI_SUBSYSTEM_VENDOR_ID,
pci_get_word(config + PCI_VENDOR_ID));
@ -2520,6 +2533,7 @@ static void virtio_pci_bus_class_init(ObjectClass *klass, void *data)
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;
}
static const TypeInfo virtio_pci_bus_info = {

View File

@ -23,6 +23,7 @@
#include "hw/virtio/virtio-bus.h"
#include "migration/migration.h"
#include "hw/virtio/virtio-access.h"
#include "sysemu/dma.h"
/*
* The alignment to use between consumer and producer parts of vring.
@ -121,7 +122,7 @@ void virtio_queue_update_rings(VirtIODevice *vdev, int n)
static void vring_desc_read(VirtIODevice *vdev, VRingDesc *desc,
hwaddr desc_pa, int i)
{
address_space_read(&address_space_memory, desc_pa + i * sizeof(VRingDesc),
address_space_read(vdev->dma_as, desc_pa + i * sizeof(VRingDesc),
MEMTXATTRS_UNSPECIFIED, (void *)desc, sizeof(VRingDesc));
virtio_tswap64s(vdev, &desc->addr);
virtio_tswap32s(vdev, &desc->len);
@ -163,7 +164,7 @@ static inline void vring_used_write(VirtQueue *vq, VRingUsedElem *uelem,
virtio_tswap32s(vq->vdev, &uelem->id);
virtio_tswap32s(vq->vdev, &uelem->len);
pa = vq->vring.used + offsetof(VRingUsed, ring[i]);
address_space_write(&address_space_memory, pa, MEMTXATTRS_UNSPECIFIED,
address_space_write(vq->vdev->dma_as, pa, MEMTXATTRS_UNSPECIFIED,
(void *)uelem, sizeof(VRingUsedElem));
}
@ -249,6 +250,7 @@ int virtio_queue_empty(VirtQueue *vq)
static void virtqueue_unmap_sg(VirtQueue *vq, const VirtQueueElement *elem,
unsigned int len)
{
AddressSpace *dma_as = vq->vdev->dma_as;
unsigned int offset;
int i;
@ -256,17 +258,18 @@ static void virtqueue_unmap_sg(VirtQueue *vq, const VirtQueueElement *elem,
for (i = 0; i < elem->in_num; i++) {
size_t size = MIN(len - offset, elem->in_sg[i].iov_len);
cpu_physical_memory_unmap(elem->in_sg[i].iov_base,
elem->in_sg[i].iov_len,
1, size);
dma_memory_unmap(dma_as, elem->in_sg[i].iov_base,
elem->in_sg[i].iov_len,
DMA_DIRECTION_FROM_DEVICE, size);
offset += size;
}
for (i = 0; i < elem->out_num; i++)
cpu_physical_memory_unmap(elem->out_sg[i].iov_base,
elem->out_sg[i].iov_len,
0, elem->out_sg[i].iov_len);
dma_memory_unmap(dma_as, elem->out_sg[i].iov_base,
elem->out_sg[i].iov_len,
DMA_DIRECTION_TO_DEVICE,
elem->out_sg[i].iov_len);
}
/* virtqueue_detach_element:
@ -560,7 +563,10 @@ static bool virtqueue_map_desc(VirtIODevice *vdev, unsigned int *p_num_sg,
goto out;
}
iov[num_sg].iov_base = cpu_physical_memory_map(pa, &len, is_write);
iov[num_sg].iov_base = dma_memory_map(vdev->dma_as, pa, &len,
is_write ?
DMA_DIRECTION_FROM_DEVICE :
DMA_DIRECTION_TO_DEVICE);
if (!iov[num_sg].iov_base) {
virtio_error(vdev, "virtio: bogus descriptor or out of resources");
goto out;
@ -597,9 +603,9 @@ static void virtqueue_undo_map_desc(unsigned int out_num, unsigned int in_num,
}
}
static void virtqueue_map_iovec(struct iovec *sg, hwaddr *addr,
unsigned int *num_sg, unsigned int max_size,
int is_write)
static void virtqueue_map_iovec(VirtIODevice *vdev, struct iovec *sg,
hwaddr *addr, unsigned int *num_sg,
unsigned int max_size, int is_write)
{
unsigned int i;
hwaddr len;
@ -618,7 +624,10 @@ static void virtqueue_map_iovec(struct iovec *sg, hwaddr *addr,
for (i = 0; i < *num_sg; i++) {
len = sg[i].iov_len;
sg[i].iov_base = cpu_physical_memory_map(addr[i], &len, is_write);
sg[i].iov_base = dma_memory_map(vdev->dma_as,
addr[i], &len, is_write ?
DMA_DIRECTION_FROM_DEVICE :
DMA_DIRECTION_TO_DEVICE);
if (!sg[i].iov_base) {
error_report("virtio: error trying to map MMIO memory");
exit(1);
@ -630,12 +639,15 @@ static void virtqueue_map_iovec(struct iovec *sg, hwaddr *addr,
}
}
void virtqueue_map(VirtQueueElement *elem)
void virtqueue_map(VirtIODevice *vdev, VirtQueueElement *elem)
{
virtqueue_map_iovec(elem->in_sg, elem->in_addr, &elem->in_num,
VIRTQUEUE_MAX_SIZE, 1);
virtqueue_map_iovec(elem->out_sg, elem->out_addr, &elem->out_num,
VIRTQUEUE_MAX_SIZE, 0);
virtqueue_map_iovec(vdev, elem->in_sg, elem->in_addr, &elem->in_num,
MIN(ARRAY_SIZE(elem->in_sg), ARRAY_SIZE(elem->in_addr)),
1);
virtqueue_map_iovec(vdev, elem->out_sg, elem->out_addr, &elem->out_num,
MIN(ARRAY_SIZE(elem->out_sg),
ARRAY_SIZE(elem->out_addr)),
0);
}
static void *virtqueue_alloc_element(size_t sz, unsigned out_num, unsigned in_num)
@ -788,7 +800,7 @@ typedef struct VirtQueueElementOld {
struct iovec out_sg[VIRTQUEUE_MAX_SIZE];
} VirtQueueElementOld;
void *qemu_get_virtqueue_element(QEMUFile *f, size_t sz)
void *qemu_get_virtqueue_element(VirtIODevice *vdev, QEMUFile *f, size_t sz)
{
VirtQueueElement *elem;
VirtQueueElementOld data;
@ -819,7 +831,7 @@ void *qemu_get_virtqueue_element(QEMUFile *f, size_t sz)
elem->out_sg[i].iov_len = data.out_sg[i].iov_len;
}
virtqueue_map(elem);
virtqueue_map(vdev, elem);
return elem;
}
@ -878,6 +890,11 @@ static int virtio_validate_features(VirtIODevice *vdev)
{
VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev);
if (virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM) &&
!virtio_vdev_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM)) {
return -EFAULT;
}
if (k->validate_features) {
return k->validate_features(vdev);
} else {

View File

@ -17,6 +17,7 @@
#define QEMU_VIRTIO_ACCESS_H
#include "hw/virtio/virtio.h"
#include "hw/virtio/virtio-bus.h"
#include "exec/address-spaces.h"
#if defined(TARGET_PPC64) || defined(TARGET_ARM)
@ -40,45 +41,55 @@ static inline bool virtio_access_is_big_endian(VirtIODevice *vdev)
static inline uint16_t virtio_lduw_phys(VirtIODevice *vdev, hwaddr pa)
{
AddressSpace *dma_as = vdev->dma_as;
if (virtio_access_is_big_endian(vdev)) {
return lduw_be_phys(&address_space_memory, pa);
return lduw_be_phys(dma_as, pa);
}
return lduw_le_phys(&address_space_memory, pa);
return lduw_le_phys(dma_as, pa);
}
static inline uint32_t virtio_ldl_phys(VirtIODevice *vdev, hwaddr pa)
{
AddressSpace *dma_as = vdev->dma_as;
if (virtio_access_is_big_endian(vdev)) {
return ldl_be_phys(&address_space_memory, pa);
return ldl_be_phys(dma_as, pa);
}
return ldl_le_phys(&address_space_memory, pa);
return ldl_le_phys(dma_as, pa);
}
static inline uint64_t virtio_ldq_phys(VirtIODevice *vdev, hwaddr pa)
{
AddressSpace *dma_as = vdev->dma_as;
if (virtio_access_is_big_endian(vdev)) {
return ldq_be_phys(&address_space_memory, pa);
return ldq_be_phys(dma_as, pa);
}
return ldq_le_phys(&address_space_memory, pa);
return ldq_le_phys(dma_as, pa);
}
static inline void virtio_stw_phys(VirtIODevice *vdev, hwaddr pa,
uint16_t value)
{
AddressSpace *dma_as = vdev->dma_as;
if (virtio_access_is_big_endian(vdev)) {
stw_be_phys(&address_space_memory, pa, value);
stw_be_phys(dma_as, pa, value);
} else {
stw_le_phys(&address_space_memory, pa, value);
stw_le_phys(dma_as, pa, value);
}
}
static inline void virtio_stl_phys(VirtIODevice *vdev, hwaddr pa,
uint32_t value)
{
AddressSpace *dma_as = vdev->dma_as;
if (virtio_access_is_big_endian(vdev)) {
stl_be_phys(&address_space_memory, pa, value);
stl_be_phys(dma_as, pa, value);
} else {
stl_le_phys(&address_space_memory, pa, value);
stl_le_phys(dma_as, pa, value);
}
}

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@ -88,6 +88,7 @@ typedef struct VirtioBusClass {
* Note that changing this will break migration for this transport.
*/
bool has_variable_vring_alignment;
AddressSpace *(*get_dma_as)(DeviceState *d);
} VirtioBusClass;
struct VirtioBusState {

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@ -92,6 +92,7 @@ struct VirtIODevice
char *bus_name;
uint8_t device_endian;
bool use_guest_notifier_mask;
AddressSpace *dma_as;
QLIST_HEAD(, VirtQueue) *vector_queues;
};
@ -170,9 +171,9 @@ bool virtqueue_rewind(VirtQueue *vq, unsigned int num);
void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
unsigned int len, unsigned int idx);
void virtqueue_map(VirtQueueElement *elem);
void virtqueue_map(VirtIODevice *vdev, VirtQueueElement *elem);
void *virtqueue_pop(VirtQueue *vq, size_t sz);
void *qemu_get_virtqueue_element(QEMUFile *f, size_t sz);
void *qemu_get_virtqueue_element(VirtIODevice *vdev, QEMUFile *f, size_t sz);
void qemu_put_virtqueue_element(QEMUFile *f, VirtQueueElement *elem);
int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes,
unsigned int out_bytes);
@ -255,7 +256,9 @@ typedef struct VirtIORNGConf VirtIORNGConf;
DEFINE_PROP_BIT64("notify_on_empty", _state, _field, \
VIRTIO_F_NOTIFY_ON_EMPTY, true), \
DEFINE_PROP_BIT64("any_layout", _state, _field, \
VIRTIO_F_ANY_LAYOUT, true)
VIRTIO_F_ANY_LAYOUT, true), \
DEFINE_PROP_BIT64("iommu_platform", _state, _field, \
VIRTIO_F_IOMMU_PLATFORM, false)
hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n);
hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n);