qemu/net/vhost-vdpa.c
Eugenio Pérez babf8b8712 vdpa: map shadow vrings with MAP_SHARED
The vdpa devices that use va addresses neeeds these maps shared.
Otherwise, vhost_vdpa checks will refuse to accept the maps.

The mmap call will always return a page aligned address, so removing the
qemu_memalign call.  Keeping the ROUND_UP for the size as we still need
to DMA-map them in full.

Not applying fixes tag as it never worked with va devices.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20230602143854.1879091-4-eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-06-26 09:50:00 -04:00

1073 lines
32 KiB
C

/*
* vhost-vdpa.c
*
* Copyright(c) 2017-2018 Intel Corporation.
* Copyright(c) 2020 Red Hat, Inc.
*
* 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 "qemu/osdep.h"
#include "clients.h"
#include "hw/virtio/virtio-net.h"
#include "net/vhost_net.h"
#include "net/vhost-vdpa.h"
#include "hw/virtio/vhost-vdpa.h"
#include "qemu/config-file.h"
#include "qemu/error-report.h"
#include "qemu/log.h"
#include "qemu/memalign.h"
#include "qemu/option.h"
#include "qapi/error.h"
#include <linux/vhost.h>
#include <sys/ioctl.h>
#include <err.h>
#include "standard-headers/linux/virtio_net.h"
#include "monitor/monitor.h"
#include "migration/migration.h"
#include "migration/misc.h"
#include "hw/virtio/vhost.h"
/* Todo:need to add the multiqueue support here */
typedef struct VhostVDPAState {
NetClientState nc;
struct vhost_vdpa vhost_vdpa;
Notifier migration_state;
VHostNetState *vhost_net;
/* Control commands shadow buffers */
void *cvq_cmd_out_buffer;
virtio_net_ctrl_ack *status;
/* The device always have SVQ enabled */
bool always_svq;
/* The device can isolate CVQ in its own ASID */
bool cvq_isolated;
bool started;
} VhostVDPAState;
const int vdpa_feature_bits[] = {
VIRTIO_F_NOTIFY_ON_EMPTY,
VIRTIO_RING_F_INDIRECT_DESC,
VIRTIO_RING_F_EVENT_IDX,
VIRTIO_F_ANY_LAYOUT,
VIRTIO_F_VERSION_1,
VIRTIO_NET_F_CSUM,
VIRTIO_NET_F_GUEST_CSUM,
VIRTIO_NET_F_GSO,
VIRTIO_NET_F_GUEST_TSO4,
VIRTIO_NET_F_GUEST_TSO6,
VIRTIO_NET_F_GUEST_ECN,
VIRTIO_NET_F_GUEST_UFO,
VIRTIO_NET_F_HOST_TSO4,
VIRTIO_NET_F_HOST_TSO6,
VIRTIO_NET_F_HOST_ECN,
VIRTIO_NET_F_HOST_UFO,
VIRTIO_NET_F_MRG_RXBUF,
VIRTIO_NET_F_MTU,
VIRTIO_NET_F_CTRL_RX,
VIRTIO_NET_F_CTRL_RX_EXTRA,
VIRTIO_NET_F_CTRL_VLAN,
VIRTIO_NET_F_CTRL_MAC_ADDR,
VIRTIO_NET_F_RSS,
VIRTIO_NET_F_MQ,
VIRTIO_NET_F_CTRL_VQ,
VIRTIO_F_IOMMU_PLATFORM,
VIRTIO_F_RING_PACKED,
VIRTIO_F_RING_RESET,
VIRTIO_NET_F_RSS,
VIRTIO_NET_F_HASH_REPORT,
VIRTIO_NET_F_STATUS,
VHOST_INVALID_FEATURE_BIT
};
/** Supported device specific feature bits with SVQ */
static const uint64_t vdpa_svq_device_features =
BIT_ULL(VIRTIO_NET_F_CSUM) |
BIT_ULL(VIRTIO_NET_F_GUEST_CSUM) |
BIT_ULL(VIRTIO_NET_F_MTU) |
BIT_ULL(VIRTIO_NET_F_MAC) |
BIT_ULL(VIRTIO_NET_F_GUEST_TSO4) |
BIT_ULL(VIRTIO_NET_F_GUEST_TSO6) |
BIT_ULL(VIRTIO_NET_F_GUEST_ECN) |
BIT_ULL(VIRTIO_NET_F_GUEST_UFO) |
BIT_ULL(VIRTIO_NET_F_HOST_TSO4) |
BIT_ULL(VIRTIO_NET_F_HOST_TSO6) |
BIT_ULL(VIRTIO_NET_F_HOST_ECN) |
BIT_ULL(VIRTIO_NET_F_HOST_UFO) |
BIT_ULL(VIRTIO_NET_F_MRG_RXBUF) |
BIT_ULL(VIRTIO_NET_F_STATUS) |
BIT_ULL(VIRTIO_NET_F_CTRL_VQ) |
BIT_ULL(VIRTIO_NET_F_MQ) |
BIT_ULL(VIRTIO_F_ANY_LAYOUT) |
BIT_ULL(VIRTIO_NET_F_CTRL_MAC_ADDR) |
/* VHOST_F_LOG_ALL is exposed by SVQ */
BIT_ULL(VHOST_F_LOG_ALL) |
BIT_ULL(VIRTIO_NET_F_RSC_EXT) |
BIT_ULL(VIRTIO_NET_F_STANDBY) |
BIT_ULL(VIRTIO_NET_F_SPEED_DUPLEX);
#define VHOST_VDPA_NET_CVQ_ASID 1
VHostNetState *vhost_vdpa_get_vhost_net(NetClientState *nc)
{
VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
return s->vhost_net;
}
static size_t vhost_vdpa_net_cvq_cmd_len(void)
{
/*
* MAC_TABLE_SET is the ctrl command that produces the longer out buffer.
* In buffer is always 1 byte, so it should fit here
*/
return sizeof(struct virtio_net_ctrl_hdr) +
2 * sizeof(struct virtio_net_ctrl_mac) +
MAC_TABLE_ENTRIES * ETH_ALEN;
}
static size_t vhost_vdpa_net_cvq_cmd_page_len(void)
{
return ROUND_UP(vhost_vdpa_net_cvq_cmd_len(), qemu_real_host_page_size());
}
static bool vhost_vdpa_net_valid_svq_features(uint64_t features, Error **errp)
{
uint64_t invalid_dev_features =
features & ~vdpa_svq_device_features &
/* Transport are all accepted at this point */
~MAKE_64BIT_MASK(VIRTIO_TRANSPORT_F_START,
VIRTIO_TRANSPORT_F_END - VIRTIO_TRANSPORT_F_START);
if (invalid_dev_features) {
error_setg(errp, "vdpa svq does not work with features 0x%" PRIx64,
invalid_dev_features);
return false;
}
return vhost_svq_valid_features(features, errp);
}
static int vhost_vdpa_net_check_device_id(struct vhost_net *net)
{
uint32_t device_id;
int ret;
struct vhost_dev *hdev;
hdev = (struct vhost_dev *)&net->dev;
ret = hdev->vhost_ops->vhost_get_device_id(hdev, &device_id);
if (device_id != VIRTIO_ID_NET) {
return -ENOTSUP;
}
return ret;
}
static int vhost_vdpa_add(NetClientState *ncs, void *be,
int queue_pair_index, int nvqs)
{
VhostNetOptions options;
struct vhost_net *net = NULL;
VhostVDPAState *s;
int ret;
options.backend_type = VHOST_BACKEND_TYPE_VDPA;
assert(ncs->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
s = DO_UPCAST(VhostVDPAState, nc, ncs);
options.net_backend = ncs;
options.opaque = be;
options.busyloop_timeout = 0;
options.nvqs = nvqs;
net = vhost_net_init(&options);
if (!net) {
error_report("failed to init vhost_net for queue");
goto err_init;
}
s->vhost_net = net;
ret = vhost_vdpa_net_check_device_id(net);
if (ret) {
goto err_check;
}
return 0;
err_check:
vhost_net_cleanup(net);
g_free(net);
err_init:
return -1;
}
static void vhost_vdpa_cleanup(NetClientState *nc)
{
VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
munmap(s->cvq_cmd_out_buffer, vhost_vdpa_net_cvq_cmd_page_len());
munmap(s->status, vhost_vdpa_net_cvq_cmd_page_len());
if (s->vhost_net) {
vhost_net_cleanup(s->vhost_net);
g_free(s->vhost_net);
s->vhost_net = NULL;
}
if (s->vhost_vdpa.device_fd >= 0) {
qemu_close(s->vhost_vdpa.device_fd);
s->vhost_vdpa.device_fd = -1;
}
}
static bool vhost_vdpa_has_vnet_hdr(NetClientState *nc)
{
assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
return true;
}
static bool vhost_vdpa_has_ufo(NetClientState *nc)
{
assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
uint64_t features = 0;
features |= (1ULL << VIRTIO_NET_F_HOST_UFO);
features = vhost_net_get_features(s->vhost_net, features);
return !!(features & (1ULL << VIRTIO_NET_F_HOST_UFO));
}
static bool vhost_vdpa_check_peer_type(NetClientState *nc, ObjectClass *oc,
Error **errp)
{
const char *driver = object_class_get_name(oc);
if (!g_str_has_prefix(driver, "virtio-net-")) {
error_setg(errp, "vhost-vdpa requires frontend driver virtio-net-*");
return false;
}
return true;
}
/** Dummy receive in case qemu falls back to userland tap networking */
static ssize_t vhost_vdpa_receive(NetClientState *nc, const uint8_t *buf,
size_t size)
{
return size;
}
/** From any vdpa net client, get the netclient of the first queue pair */
static VhostVDPAState *vhost_vdpa_net_first_nc_vdpa(VhostVDPAState *s)
{
NICState *nic = qemu_get_nic(s->nc.peer);
NetClientState *nc0 = qemu_get_peer(nic->ncs, 0);
return DO_UPCAST(VhostVDPAState, nc, nc0);
}
static void vhost_vdpa_net_log_global_enable(VhostVDPAState *s, bool enable)
{
struct vhost_vdpa *v = &s->vhost_vdpa;
VirtIONet *n;
VirtIODevice *vdev;
int data_queue_pairs, cvq, r;
/* We are only called on the first data vqs and only if x-svq is not set */
if (s->vhost_vdpa.shadow_vqs_enabled == enable) {
return;
}
vdev = v->dev->vdev;
n = VIRTIO_NET(vdev);
if (!n->vhost_started) {
return;
}
data_queue_pairs = n->multiqueue ? n->max_queue_pairs : 1;
cvq = virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) ?
n->max_ncs - n->max_queue_pairs : 0;
/*
* TODO: vhost_net_stop does suspend, get_base and reset. We can be smarter
* in the future and resume the device if read-only operations between
* suspend and reset goes wrong.
*/
vhost_net_stop(vdev, n->nic->ncs, data_queue_pairs, cvq);
/* Start will check migration setup_or_active to configure or not SVQ */
r = vhost_net_start(vdev, n->nic->ncs, data_queue_pairs, cvq);
if (unlikely(r < 0)) {
error_report("unable to start vhost net: %s(%d)", g_strerror(-r), -r);
}
}
static void vdpa_net_migration_state_notifier(Notifier *notifier, void *data)
{
MigrationState *migration = data;
VhostVDPAState *s = container_of(notifier, VhostVDPAState,
migration_state);
if (migration_in_setup(migration)) {
vhost_vdpa_net_log_global_enable(s, true);
} else if (migration_has_failed(migration)) {
vhost_vdpa_net_log_global_enable(s, false);
}
}
static void vhost_vdpa_net_data_start_first(VhostVDPAState *s)
{
struct vhost_vdpa *v = &s->vhost_vdpa;
add_migration_state_change_notifier(&s->migration_state);
if (v->shadow_vqs_enabled) {
v->iova_tree = vhost_iova_tree_new(v->iova_range.first,
v->iova_range.last);
}
}
static int vhost_vdpa_net_data_start(NetClientState *nc)
{
VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
struct vhost_vdpa *v = &s->vhost_vdpa;
assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
if (s->always_svq ||
migration_is_setup_or_active(migrate_get_current()->state)) {
v->shadow_vqs_enabled = true;
v->shadow_data = true;
} else {
v->shadow_vqs_enabled = false;
v->shadow_data = false;
}
if (v->index == 0) {
vhost_vdpa_net_data_start_first(s);
return 0;
}
if (v->shadow_vqs_enabled) {
VhostVDPAState *s0 = vhost_vdpa_net_first_nc_vdpa(s);
v->iova_tree = s0->vhost_vdpa.iova_tree;
}
return 0;
}
static void vhost_vdpa_net_client_stop(NetClientState *nc)
{
VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
struct vhost_dev *dev;
assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
if (s->vhost_vdpa.index == 0) {
remove_migration_state_change_notifier(&s->migration_state);
}
dev = s->vhost_vdpa.dev;
if (dev->vq_index + dev->nvqs == dev->vq_index_end) {
g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete);
}
}
static NetClientInfo net_vhost_vdpa_info = {
.type = NET_CLIENT_DRIVER_VHOST_VDPA,
.size = sizeof(VhostVDPAState),
.receive = vhost_vdpa_receive,
.start = vhost_vdpa_net_data_start,
.stop = vhost_vdpa_net_client_stop,
.cleanup = vhost_vdpa_cleanup,
.has_vnet_hdr = vhost_vdpa_has_vnet_hdr,
.has_ufo = vhost_vdpa_has_ufo,
.check_peer_type = vhost_vdpa_check_peer_type,
};
static int64_t vhost_vdpa_get_vring_group(int device_fd, unsigned vq_index,
Error **errp)
{
struct vhost_vring_state state = {
.index = vq_index,
};
int r = ioctl(device_fd, VHOST_VDPA_GET_VRING_GROUP, &state);
if (unlikely(r < 0)) {
r = -errno;
error_setg_errno(errp, errno, "Cannot get VQ %u group", vq_index);
return r;
}
return state.num;
}
static int vhost_vdpa_set_address_space_id(struct vhost_vdpa *v,
unsigned vq_group,
unsigned asid_num)
{
struct vhost_vring_state asid = {
.index = vq_group,
.num = asid_num,
};
int r;
r = ioctl(v->device_fd, VHOST_VDPA_SET_GROUP_ASID, &asid);
if (unlikely(r < 0)) {
error_report("Can't set vq group %u asid %u, errno=%d (%s)",
asid.index, asid.num, errno, g_strerror(errno));
}
return r;
}
static void vhost_vdpa_cvq_unmap_buf(struct vhost_vdpa *v, void *addr)
{
VhostIOVATree *tree = v->iova_tree;
DMAMap needle = {
/*
* No need to specify size or to look for more translations since
* this contiguous chunk was allocated by us.
*/
.translated_addr = (hwaddr)(uintptr_t)addr,
};
const DMAMap *map = vhost_iova_tree_find_iova(tree, &needle);
int r;
if (unlikely(!map)) {
error_report("Cannot locate expected map");
return;
}
r = vhost_vdpa_dma_unmap(v, v->address_space_id, map->iova, map->size + 1);
if (unlikely(r != 0)) {
error_report("Device cannot unmap: %s(%d)", g_strerror(r), r);
}
vhost_iova_tree_remove(tree, *map);
}
/** Map CVQ buffer. */
static int vhost_vdpa_cvq_map_buf(struct vhost_vdpa *v, void *buf, size_t size,
bool write)
{
DMAMap map = {};
int r;
map.translated_addr = (hwaddr)(uintptr_t)buf;
map.size = size - 1;
map.perm = write ? IOMMU_RW : IOMMU_RO,
r = vhost_iova_tree_map_alloc(v->iova_tree, &map);
if (unlikely(r != IOVA_OK)) {
error_report("Cannot map injected element");
return r;
}
r = vhost_vdpa_dma_map(v, v->address_space_id, map.iova,
vhost_vdpa_net_cvq_cmd_page_len(), buf, !write);
if (unlikely(r < 0)) {
goto dma_map_err;
}
return 0;
dma_map_err:
vhost_iova_tree_remove(v->iova_tree, map);
return r;
}
static int vhost_vdpa_net_cvq_start(NetClientState *nc)
{
VhostVDPAState *s, *s0;
struct vhost_vdpa *v;
int64_t cvq_group;
int r;
Error *err = NULL;
assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
s = DO_UPCAST(VhostVDPAState, nc, nc);
v = &s->vhost_vdpa;
s0 = vhost_vdpa_net_first_nc_vdpa(s);
v->shadow_data = s0->vhost_vdpa.shadow_vqs_enabled;
v->shadow_vqs_enabled = s->always_svq;
s->vhost_vdpa.address_space_id = VHOST_VDPA_GUEST_PA_ASID;
if (s->vhost_vdpa.shadow_data) {
/* SVQ is already configured for all virtqueues */
goto out;
}
/*
* If we early return in these cases SVQ will not be enabled. The migration
* will be blocked as long as vhost-vdpa backends will not offer _F_LOG.
*/
if (!vhost_vdpa_net_valid_svq_features(v->dev->features, NULL)) {
return 0;
}
if (!s->cvq_isolated) {
return 0;
}
cvq_group = vhost_vdpa_get_vring_group(v->device_fd,
v->dev->vq_index_end - 1,
&err);
if (unlikely(cvq_group < 0)) {
error_report_err(err);
return cvq_group;
}
r = vhost_vdpa_set_address_space_id(v, cvq_group, VHOST_VDPA_NET_CVQ_ASID);
if (unlikely(r < 0)) {
return r;
}
v->shadow_vqs_enabled = true;
s->vhost_vdpa.address_space_id = VHOST_VDPA_NET_CVQ_ASID;
out:
if (!s->vhost_vdpa.shadow_vqs_enabled) {
return 0;
}
if (s0->vhost_vdpa.iova_tree) {
/*
* SVQ is already configured for all virtqueues. Reuse IOVA tree for
* simplicity, whether CVQ shares ASID with guest or not, because:
* - Memory listener need access to guest's memory addresses allocated
* in the IOVA tree.
* - There should be plenty of IOVA address space for both ASID not to
* worry about collisions between them. Guest's translations are
* still validated with virtio virtqueue_pop so there is no risk for
* the guest to access memory that it shouldn't.
*
* To allocate a iova tree per ASID is doable but it complicates the
* code and it is not worth it for the moment.
*/
v->iova_tree = s0->vhost_vdpa.iova_tree;
} else {
v->iova_tree = vhost_iova_tree_new(v->iova_range.first,
v->iova_range.last);
}
r = vhost_vdpa_cvq_map_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer,
vhost_vdpa_net_cvq_cmd_page_len(), false);
if (unlikely(r < 0)) {
return r;
}
r = vhost_vdpa_cvq_map_buf(&s->vhost_vdpa, s->status,
vhost_vdpa_net_cvq_cmd_page_len(), true);
if (unlikely(r < 0)) {
vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer);
}
return r;
}
static void vhost_vdpa_net_cvq_stop(NetClientState *nc)
{
VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
if (s->vhost_vdpa.shadow_vqs_enabled) {
vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer);
vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->status);
}
vhost_vdpa_net_client_stop(nc);
}
static ssize_t vhost_vdpa_net_cvq_add(VhostVDPAState *s, size_t out_len,
size_t in_len)
{
/* Buffers for the device */
const struct iovec out = {
.iov_base = s->cvq_cmd_out_buffer,
.iov_len = out_len,
};
const struct iovec in = {
.iov_base = s->status,
.iov_len = sizeof(virtio_net_ctrl_ack),
};
VhostShadowVirtqueue *svq = g_ptr_array_index(s->vhost_vdpa.shadow_vqs, 0);
int r;
r = vhost_svq_add(svq, &out, 1, &in, 1, NULL);
if (unlikely(r != 0)) {
if (unlikely(r == -ENOSPC)) {
qemu_log_mask(LOG_GUEST_ERROR, "%s: No space on device queue\n",
__func__);
}
return r;
}
/*
* We can poll here since we've had BQL from the time we sent the
* descriptor. Also, we need to take the answer before SVQ pulls by itself,
* when BQL is released
*/
return vhost_svq_poll(svq);
}
static ssize_t vhost_vdpa_net_load_cmd(VhostVDPAState *s, uint8_t class,
uint8_t cmd, const void *data,
size_t data_size)
{
const struct virtio_net_ctrl_hdr ctrl = {
.class = class,
.cmd = cmd,
};
assert(data_size < vhost_vdpa_net_cvq_cmd_page_len() - sizeof(ctrl));
memcpy(s->cvq_cmd_out_buffer, &ctrl, sizeof(ctrl));
memcpy(s->cvq_cmd_out_buffer + sizeof(ctrl), data, data_size);
return vhost_vdpa_net_cvq_add(s, sizeof(ctrl) + data_size,
sizeof(virtio_net_ctrl_ack));
}
static int vhost_vdpa_net_load_mac(VhostVDPAState *s, const VirtIONet *n)
{
uint64_t features = n->parent_obj.guest_features;
if (features & BIT_ULL(VIRTIO_NET_F_CTRL_MAC_ADDR)) {
ssize_t dev_written = vhost_vdpa_net_load_cmd(s, VIRTIO_NET_CTRL_MAC,
VIRTIO_NET_CTRL_MAC_ADDR_SET,
n->mac, sizeof(n->mac));
if (unlikely(dev_written < 0)) {
return dev_written;
}
return *s->status != VIRTIO_NET_OK;
}
return 0;
}
static int vhost_vdpa_net_load_mq(VhostVDPAState *s,
const VirtIONet *n)
{
struct virtio_net_ctrl_mq mq;
uint64_t features = n->parent_obj.guest_features;
ssize_t dev_written;
if (!(features & BIT_ULL(VIRTIO_NET_F_MQ))) {
return 0;
}
mq.virtqueue_pairs = cpu_to_le16(n->curr_queue_pairs);
dev_written = vhost_vdpa_net_load_cmd(s, VIRTIO_NET_CTRL_MQ,
VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &mq,
sizeof(mq));
if (unlikely(dev_written < 0)) {
return dev_written;
}
return *s->status != VIRTIO_NET_OK;
}
static int vhost_vdpa_net_load(NetClientState *nc)
{
VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
struct vhost_vdpa *v = &s->vhost_vdpa;
const VirtIONet *n;
int r;
assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
if (!v->shadow_vqs_enabled) {
return 0;
}
n = VIRTIO_NET(v->dev->vdev);
r = vhost_vdpa_net_load_mac(s, n);
if (unlikely(r < 0)) {
return r;
}
r = vhost_vdpa_net_load_mq(s, n);
if (unlikely(r)) {
return r;
}
return 0;
}
static NetClientInfo net_vhost_vdpa_cvq_info = {
.type = NET_CLIENT_DRIVER_VHOST_VDPA,
.size = sizeof(VhostVDPAState),
.receive = vhost_vdpa_receive,
.start = vhost_vdpa_net_cvq_start,
.load = vhost_vdpa_net_load,
.stop = vhost_vdpa_net_cvq_stop,
.cleanup = vhost_vdpa_cleanup,
.has_vnet_hdr = vhost_vdpa_has_vnet_hdr,
.has_ufo = vhost_vdpa_has_ufo,
.check_peer_type = vhost_vdpa_check_peer_type,
};
/**
* Validate and copy control virtqueue commands.
*
* Following QEMU guidelines, we offer a copy of the buffers to the device to
* prevent TOCTOU bugs.
*/
static int vhost_vdpa_net_handle_ctrl_avail(VhostShadowVirtqueue *svq,
VirtQueueElement *elem,
void *opaque)
{
VhostVDPAState *s = opaque;
size_t in_len;
virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
/* Out buffer sent to both the vdpa device and the device model */
struct iovec out = {
.iov_base = s->cvq_cmd_out_buffer,
};
/* in buffer used for device model */
const struct iovec in = {
.iov_base = &status,
.iov_len = sizeof(status),
};
ssize_t dev_written = -EINVAL;
out.iov_len = iov_to_buf(elem->out_sg, elem->out_num, 0,
s->cvq_cmd_out_buffer,
vhost_vdpa_net_cvq_cmd_len());
if (*(uint8_t *)s->cvq_cmd_out_buffer == VIRTIO_NET_CTRL_ANNOUNCE) {
/*
* Guest announce capability is emulated by qemu, so don't forward to
* the device.
*/
dev_written = sizeof(status);
*s->status = VIRTIO_NET_OK;
} else {
dev_written = vhost_vdpa_net_cvq_add(s, out.iov_len, sizeof(status));
if (unlikely(dev_written < 0)) {
goto out;
}
}
if (unlikely(dev_written < sizeof(status))) {
error_report("Insufficient written data (%zu)", dev_written);
goto out;
}
if (*s->status != VIRTIO_NET_OK) {
return VIRTIO_NET_ERR;
}
status = VIRTIO_NET_ERR;
virtio_net_handle_ctrl_iov(svq->vdev, &in, 1, &out, 1);
if (status != VIRTIO_NET_OK) {
error_report("Bad CVQ processing in model");
}
out:
in_len = iov_from_buf(elem->in_sg, elem->in_num, 0, &status,
sizeof(status));
if (unlikely(in_len < sizeof(status))) {
error_report("Bad device CVQ written length");
}
vhost_svq_push_elem(svq, elem, MIN(in_len, sizeof(status)));
g_free(elem);
return dev_written < 0 ? dev_written : 0;
}
static const VhostShadowVirtqueueOps vhost_vdpa_net_svq_ops = {
.avail_handler = vhost_vdpa_net_handle_ctrl_avail,
};
/**
* Probe if CVQ is isolated
*
* @device_fd The vdpa device fd
* @features Features offered by the device.
* @cvq_index The control vq pair index
*
* Returns <0 in case of failure, 0 if false and 1 if true.
*/
static int vhost_vdpa_probe_cvq_isolation(int device_fd, uint64_t features,
int cvq_index, Error **errp)
{
uint64_t backend_features;
int64_t cvq_group;
uint8_t status = VIRTIO_CONFIG_S_ACKNOWLEDGE |
VIRTIO_CONFIG_S_DRIVER |
VIRTIO_CONFIG_S_FEATURES_OK;
int r;
ERRP_GUARD();
r = ioctl(device_fd, VHOST_GET_BACKEND_FEATURES, &backend_features);
if (unlikely(r < 0)) {
error_setg_errno(errp, errno, "Cannot get vdpa backend_features");
return r;
}
if (!(backend_features & BIT_ULL(VHOST_BACKEND_F_IOTLB_ASID))) {
return 0;
}
r = ioctl(device_fd, VHOST_SET_FEATURES, &features);
if (unlikely(r)) {
error_setg_errno(errp, errno, "Cannot set features");
}
r = ioctl(device_fd, VHOST_VDPA_SET_STATUS, &status);
if (unlikely(r)) {
error_setg_errno(errp, -r, "Cannot set device features");
goto out;
}
cvq_group = vhost_vdpa_get_vring_group(device_fd, cvq_index, errp);
if (unlikely(cvq_group < 0)) {
if (cvq_group != -ENOTSUP) {
r = cvq_group;
goto out;
}
/*
* The kernel report VHOST_BACKEND_F_IOTLB_ASID if the vdpa frontend
* support ASID even if the parent driver does not. The CVQ cannot be
* isolated in this case.
*/
error_free(*errp);
*errp = NULL;
r = 0;
goto out;
}
for (int i = 0; i < cvq_index; ++i) {
int64_t group = vhost_vdpa_get_vring_group(device_fd, i, errp);
if (unlikely(group < 0)) {
r = group;
goto out;
}
if (group == (int64_t)cvq_group) {
r = 0;
goto out;
}
}
r = 1;
out:
status = 0;
ioctl(device_fd, VHOST_VDPA_SET_STATUS, &status);
return r;
}
static NetClientState *net_vhost_vdpa_init(NetClientState *peer,
const char *device,
const char *name,
int vdpa_device_fd,
int queue_pair_index,
int nvqs,
bool is_datapath,
bool svq,
struct vhost_vdpa_iova_range iova_range,
uint64_t features,
Error **errp)
{
NetClientState *nc = NULL;
VhostVDPAState *s;
int ret = 0;
assert(name);
int cvq_isolated;
if (is_datapath) {
nc = qemu_new_net_client(&net_vhost_vdpa_info, peer, device,
name);
} else {
cvq_isolated = vhost_vdpa_probe_cvq_isolation(vdpa_device_fd, features,
queue_pair_index * 2,
errp);
if (unlikely(cvq_isolated < 0)) {
return NULL;
}
nc = qemu_new_net_control_client(&net_vhost_vdpa_cvq_info, peer,
device, name);
}
qemu_set_info_str(nc, TYPE_VHOST_VDPA);
s = DO_UPCAST(VhostVDPAState, nc, nc);
s->vhost_vdpa.device_fd = vdpa_device_fd;
s->vhost_vdpa.index = queue_pair_index;
s->always_svq = svq;
s->migration_state.notify = vdpa_net_migration_state_notifier;
s->vhost_vdpa.shadow_vqs_enabled = svq;
s->vhost_vdpa.iova_range = iova_range;
s->vhost_vdpa.shadow_data = svq;
if (queue_pair_index == 0) {
vhost_vdpa_net_valid_svq_features(features,
&s->vhost_vdpa.migration_blocker);
} else if (!is_datapath) {
s->cvq_cmd_out_buffer = mmap(NULL, vhost_vdpa_net_cvq_cmd_page_len(),
PROT_READ | PROT_WRITE,
MAP_SHARED | MAP_ANONYMOUS, -1, 0);
s->status = mmap(NULL, vhost_vdpa_net_cvq_cmd_page_len(),
PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS,
-1, 0);
s->vhost_vdpa.shadow_vq_ops = &vhost_vdpa_net_svq_ops;
s->vhost_vdpa.shadow_vq_ops_opaque = s;
s->cvq_isolated = cvq_isolated;
/*
* TODO: We cannot migrate devices with CVQ and no x-svq enabled as
* there is no way to set the device state (MAC, MQ, etc) before
* starting the datapath.
*
* Migration blocker ownership now belongs to s->vhost_vdpa.
*/
if (!svq) {
error_setg(&s->vhost_vdpa.migration_blocker,
"net vdpa cannot migrate with CVQ feature");
}
}
ret = vhost_vdpa_add(nc, (void *)&s->vhost_vdpa, queue_pair_index, nvqs);
if (ret) {
qemu_del_net_client(nc);
return NULL;
}
return nc;
}
static int vhost_vdpa_get_features(int fd, uint64_t *features, Error **errp)
{
int ret = ioctl(fd, VHOST_GET_FEATURES, features);
if (unlikely(ret < 0)) {
error_setg_errno(errp, errno,
"Fail to query features from vhost-vDPA device");
}
return ret;
}
static int vhost_vdpa_get_max_queue_pairs(int fd, uint64_t features,
int *has_cvq, Error **errp)
{
unsigned long config_size = offsetof(struct vhost_vdpa_config, buf);
g_autofree struct vhost_vdpa_config *config = NULL;
__virtio16 *max_queue_pairs;
int ret;
if (features & (1 << VIRTIO_NET_F_CTRL_VQ)) {
*has_cvq = 1;
} else {
*has_cvq = 0;
}
if (features & (1 << VIRTIO_NET_F_MQ)) {
config = g_malloc0(config_size + sizeof(*max_queue_pairs));
config->off = offsetof(struct virtio_net_config, max_virtqueue_pairs);
config->len = sizeof(*max_queue_pairs);
ret = ioctl(fd, VHOST_VDPA_GET_CONFIG, config);
if (ret) {
error_setg(errp, "Fail to get config from vhost-vDPA device");
return -ret;
}
max_queue_pairs = (__virtio16 *)&config->buf;
return lduw_le_p(max_queue_pairs);
}
return 1;
}
int net_init_vhost_vdpa(const Netdev *netdev, const char *name,
NetClientState *peer, Error **errp)
{
const NetdevVhostVDPAOptions *opts;
uint64_t features;
int vdpa_device_fd;
g_autofree NetClientState **ncs = NULL;
struct vhost_vdpa_iova_range iova_range;
NetClientState *nc;
int queue_pairs, r, i = 0, has_cvq = 0;
assert(netdev->type == NET_CLIENT_DRIVER_VHOST_VDPA);
opts = &netdev->u.vhost_vdpa;
if (!opts->vhostdev && !opts->vhostfd) {
error_setg(errp,
"vhost-vdpa: neither vhostdev= nor vhostfd= was specified");
return -1;
}
if (opts->vhostdev && opts->vhostfd) {
error_setg(errp,
"vhost-vdpa: vhostdev= and vhostfd= are mutually exclusive");
return -1;
}
if (opts->vhostdev) {
vdpa_device_fd = qemu_open(opts->vhostdev, O_RDWR, errp);
if (vdpa_device_fd == -1) {
return -errno;
}
} else {
/* has_vhostfd */
vdpa_device_fd = monitor_fd_param(monitor_cur(), opts->vhostfd, errp);
if (vdpa_device_fd == -1) {
error_prepend(errp, "vhost-vdpa: unable to parse vhostfd: ");
return -1;
}
}
r = vhost_vdpa_get_features(vdpa_device_fd, &features, errp);
if (unlikely(r < 0)) {
goto err;
}
queue_pairs = vhost_vdpa_get_max_queue_pairs(vdpa_device_fd, features,
&has_cvq, errp);
if (queue_pairs < 0) {
qemu_close(vdpa_device_fd);
return queue_pairs;
}
r = vhost_vdpa_get_iova_range(vdpa_device_fd, &iova_range);
if (unlikely(r < 0)) {
error_setg(errp, "vhost-vdpa: get iova range failed: %s",
strerror(-r));
goto err;
}
if (opts->x_svq && !vhost_vdpa_net_valid_svq_features(features, errp)) {
goto err;
}
ncs = g_malloc0(sizeof(*ncs) * queue_pairs);
for (i = 0; i < queue_pairs; i++) {
ncs[i] = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name,
vdpa_device_fd, i, 2, true, opts->x_svq,
iova_range, features, errp);
if (!ncs[i])
goto err;
}
if (has_cvq) {
nc = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name,
vdpa_device_fd, i, 1, false,
opts->x_svq, iova_range, features, errp);
if (!nc)
goto err;
}
return 0;
err:
if (i) {
for (i--; i >= 0; i--) {
qemu_del_net_client(ncs[i]);
}
}
qemu_close(vdpa_device_fd);
return -1;
}