qemu/net/vhost-vdpa.c
Ani Sinha a0d7215e33 vhost-vdpa: do not cleanup the vdpa/vhost-net structures if peer nic is present
When a peer nic is still attached to the vdpa backend, it is too early to free
up the vhost-net and vdpa structures. If these structures are freed here, then
QEMU crashes when the guest is being shut down. The following call chain
would result in an assertion failure since the pointer returned from
vhost_vdpa_get_vhost_net() would be NULL:

do_vm_stop() -> vm_state_notify() -> virtio_set_status() ->
virtio_net_vhost_status() -> get_vhost_net().

Therefore, we defer freeing up the structures until at guest shutdown
time when qemu_cleanup() calls net_cleanup() which then calls
qemu_del_net_client() which would eventually call vhost_vdpa_cleanup()
again to free up the structures. This time, the loop in net_cleanup()
ensures that vhost_vdpa_cleanup() will be called one last time when
all the peer nics are detached and freed.

All unit tests pass with this change.

CC: imammedo@redhat.com
CC: jusual@redhat.com
CC: mst@redhat.com
Fixes: CVE-2023-3301
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2128929
Signed-off-by: Ani Sinha <anisinha@redhat.com>
Message-Id: <20230619065209.442185-1-anisinha@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

1123 lines
33 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_CTRL_GUEST_OFFLOADS,
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_CTRL_GUEST_OFFLOADS) |
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);
/*
* If a peer NIC is attached, do not cleanup anything.
* Cleanup will happen as a part of qemu_cleanup() -> net_cleanup()
* when the guest is shutting down.
*/
if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
return;
}
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)
{
if (virtio_vdev_has_feature(&n->parent_obj, 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;
ssize_t dev_written;
if (!virtio_vdev_has_feature(&n->parent_obj, 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_offloads(VhostVDPAState *s,
const VirtIONet *n)
{
uint64_t offloads;
ssize_t dev_written;
if (!virtio_vdev_has_feature(&n->parent_obj,
VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)) {
return 0;
}
if (n->curr_guest_offloads == virtio_net_supported_guest_offloads(n)) {
/*
* According to VirtIO standard, "Upon feature negotiation
* corresponding offload gets enabled to preserve
* backward compatibility.".
*
* Therefore, there is no need to send this CVQ command if the
* driver also enables all supported offloads, which aligns with
* the device's defaults.
*
* Note that the device's defaults can mismatch the driver's
* configuration only at live migration.
*/
return 0;
}
offloads = cpu_to_le64(n->curr_guest_offloads);
dev_written = vhost_vdpa_net_load_cmd(s, VIRTIO_NET_CTRL_GUEST_OFFLOADS,
VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET,
&offloads, sizeof(offloads));
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;
}
r = vhost_vdpa_net_load_offloads(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) {
goto out;
}
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;
}