xref: /openbmc/qemu/net/vhost-vdpa.c (revision 7200fb21)
1 /*
2  * vhost-vdpa.c
3  *
4  * Copyright(c) 2017-2018 Intel Corporation.
5  * Copyright(c) 2020 Red Hat, Inc.
6  *
7  * This work is licensed under the terms of the GNU GPL, version 2 or later.
8  * See the COPYING file in the top-level directory.
9  *
10  */
11 
12 #include "qemu/osdep.h"
13 #include "clients.h"
14 #include "hw/virtio/virtio-net.h"
15 #include "net/vhost_net.h"
16 #include "net/vhost-vdpa.h"
17 #include "hw/virtio/vhost-vdpa.h"
18 #include "qemu/config-file.h"
19 #include "qemu/error-report.h"
20 #include "qemu/log.h"
21 #include "qemu/memalign.h"
22 #include "qemu/option.h"
23 #include "qapi/error.h"
24 #include <linux/vhost.h>
25 #include <sys/ioctl.h>
26 #include <err.h>
27 #include "standard-headers/linux/virtio_net.h"
28 #include "monitor/monitor.h"
29 #include "migration/migration.h"
30 #include "migration/misc.h"
31 #include "hw/virtio/vhost.h"
32 
33 /* Todo:need to add the multiqueue support here */
34 typedef struct VhostVDPAState {
35     NetClientState nc;
36     struct vhost_vdpa vhost_vdpa;
37     Notifier migration_state;
38     VHostNetState *vhost_net;
39 
40     /* Control commands shadow buffers */
41     void *cvq_cmd_out_buffer;
42     virtio_net_ctrl_ack *status;
43 
44     /* The device always have SVQ enabled */
45     bool always_svq;
46 
47     /* The device can isolate CVQ in its own ASID */
48     bool cvq_isolated;
49 
50     bool started;
51 } VhostVDPAState;
52 
53 /*
54  * The array is sorted alphabetically in ascending order,
55  * with the exception of VHOST_INVALID_FEATURE_BIT,
56  * which should always be the last entry.
57  */
58 const int vdpa_feature_bits[] = {
59     VIRTIO_F_ANY_LAYOUT,
60     VIRTIO_F_IOMMU_PLATFORM,
61     VIRTIO_F_NOTIFY_ON_EMPTY,
62     VIRTIO_F_RING_PACKED,
63     VIRTIO_F_RING_RESET,
64     VIRTIO_F_VERSION_1,
65     VIRTIO_NET_F_CSUM,
66     VIRTIO_NET_F_CTRL_GUEST_OFFLOADS,
67     VIRTIO_NET_F_CTRL_MAC_ADDR,
68     VIRTIO_NET_F_CTRL_RX,
69     VIRTIO_NET_F_CTRL_RX_EXTRA,
70     VIRTIO_NET_F_CTRL_VLAN,
71     VIRTIO_NET_F_CTRL_VQ,
72     VIRTIO_NET_F_GSO,
73     VIRTIO_NET_F_GUEST_CSUM,
74     VIRTIO_NET_F_GUEST_ECN,
75     VIRTIO_NET_F_GUEST_TSO4,
76     VIRTIO_NET_F_GUEST_TSO6,
77     VIRTIO_NET_F_GUEST_UFO,
78     VIRTIO_NET_F_GUEST_USO4,
79     VIRTIO_NET_F_GUEST_USO6,
80     VIRTIO_NET_F_HASH_REPORT,
81     VIRTIO_NET_F_HOST_ECN,
82     VIRTIO_NET_F_HOST_TSO4,
83     VIRTIO_NET_F_HOST_TSO6,
84     VIRTIO_NET_F_HOST_UFO,
85     VIRTIO_NET_F_HOST_USO,
86     VIRTIO_NET_F_MQ,
87     VIRTIO_NET_F_MRG_RXBUF,
88     VIRTIO_NET_F_MTU,
89     VIRTIO_NET_F_RSS,
90     VIRTIO_NET_F_STATUS,
91     VIRTIO_RING_F_EVENT_IDX,
92     VIRTIO_RING_F_INDIRECT_DESC,
93 
94     /* VHOST_INVALID_FEATURE_BIT should always be the last entry */
95     VHOST_INVALID_FEATURE_BIT
96 };
97 
98 /** Supported device specific feature bits with SVQ */
99 static const uint64_t vdpa_svq_device_features =
100     BIT_ULL(VIRTIO_NET_F_CSUM) |
101     BIT_ULL(VIRTIO_NET_F_GUEST_CSUM) |
102     BIT_ULL(VIRTIO_NET_F_CTRL_GUEST_OFFLOADS) |
103     BIT_ULL(VIRTIO_NET_F_MTU) |
104     BIT_ULL(VIRTIO_NET_F_MAC) |
105     BIT_ULL(VIRTIO_NET_F_GUEST_TSO4) |
106     BIT_ULL(VIRTIO_NET_F_GUEST_TSO6) |
107     BIT_ULL(VIRTIO_NET_F_GUEST_ECN) |
108     BIT_ULL(VIRTIO_NET_F_GUEST_UFO) |
109     BIT_ULL(VIRTIO_NET_F_HOST_TSO4) |
110     BIT_ULL(VIRTIO_NET_F_HOST_TSO6) |
111     BIT_ULL(VIRTIO_NET_F_HOST_ECN) |
112     BIT_ULL(VIRTIO_NET_F_HOST_UFO) |
113     BIT_ULL(VIRTIO_NET_F_MRG_RXBUF) |
114     BIT_ULL(VIRTIO_NET_F_STATUS) |
115     BIT_ULL(VIRTIO_NET_F_CTRL_VQ) |
116     BIT_ULL(VIRTIO_NET_F_CTRL_RX) |
117     BIT_ULL(VIRTIO_NET_F_CTRL_VLAN) |
118     BIT_ULL(VIRTIO_NET_F_CTRL_RX_EXTRA) |
119     BIT_ULL(VIRTIO_NET_F_MQ) |
120     BIT_ULL(VIRTIO_F_ANY_LAYOUT) |
121     BIT_ULL(VIRTIO_NET_F_CTRL_MAC_ADDR) |
122     /* VHOST_F_LOG_ALL is exposed by SVQ */
123     BIT_ULL(VHOST_F_LOG_ALL) |
124     BIT_ULL(VIRTIO_NET_F_HASH_REPORT) |
125     BIT_ULL(VIRTIO_NET_F_RSS) |
126     BIT_ULL(VIRTIO_NET_F_RSC_EXT) |
127     BIT_ULL(VIRTIO_NET_F_STANDBY) |
128     BIT_ULL(VIRTIO_NET_F_SPEED_DUPLEX);
129 
130 #define VHOST_VDPA_NET_CVQ_ASID 1
131 
132 VHostNetState *vhost_vdpa_get_vhost_net(NetClientState *nc)
133 {
134     VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
135     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
136     return s->vhost_net;
137 }
138 
139 static size_t vhost_vdpa_net_cvq_cmd_len(void)
140 {
141     /*
142      * MAC_TABLE_SET is the ctrl command that produces the longer out buffer.
143      * In buffer is always 1 byte, so it should fit here
144      */
145     return sizeof(struct virtio_net_ctrl_hdr) +
146            2 * sizeof(struct virtio_net_ctrl_mac) +
147            MAC_TABLE_ENTRIES * ETH_ALEN;
148 }
149 
150 static size_t vhost_vdpa_net_cvq_cmd_page_len(void)
151 {
152     return ROUND_UP(vhost_vdpa_net_cvq_cmd_len(), qemu_real_host_page_size());
153 }
154 
155 static bool vhost_vdpa_net_valid_svq_features(uint64_t features, Error **errp)
156 {
157     uint64_t invalid_dev_features =
158         features & ~vdpa_svq_device_features &
159         /* Transport are all accepted at this point */
160         ~MAKE_64BIT_MASK(VIRTIO_TRANSPORT_F_START,
161                          VIRTIO_TRANSPORT_F_END - VIRTIO_TRANSPORT_F_START);
162 
163     if (invalid_dev_features) {
164         error_setg(errp, "vdpa svq does not work with features 0x%" PRIx64,
165                    invalid_dev_features);
166         return false;
167     }
168 
169     return vhost_svq_valid_features(features, errp);
170 }
171 
172 static int vhost_vdpa_net_check_device_id(struct vhost_net *net)
173 {
174     uint32_t device_id;
175     int ret;
176     struct vhost_dev *hdev;
177 
178     hdev = (struct vhost_dev *)&net->dev;
179     ret = hdev->vhost_ops->vhost_get_device_id(hdev, &device_id);
180     if (device_id != VIRTIO_ID_NET) {
181         return -ENOTSUP;
182     }
183     return ret;
184 }
185 
186 static int vhost_vdpa_add(NetClientState *ncs, void *be,
187                           int queue_pair_index, int nvqs)
188 {
189     VhostNetOptions options;
190     struct vhost_net *net = NULL;
191     VhostVDPAState *s;
192     int ret;
193 
194     options.backend_type = VHOST_BACKEND_TYPE_VDPA;
195     assert(ncs->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
196     s = DO_UPCAST(VhostVDPAState, nc, ncs);
197     options.net_backend = ncs;
198     options.opaque      = be;
199     options.busyloop_timeout = 0;
200     options.nvqs = nvqs;
201 
202     net = vhost_net_init(&options);
203     if (!net) {
204         error_report("failed to init vhost_net for queue");
205         goto err_init;
206     }
207     s->vhost_net = net;
208     ret = vhost_vdpa_net_check_device_id(net);
209     if (ret) {
210         goto err_check;
211     }
212     return 0;
213 err_check:
214     vhost_net_cleanup(net);
215     g_free(net);
216 err_init:
217     return -1;
218 }
219 
220 static void vhost_vdpa_cleanup(NetClientState *nc)
221 {
222     VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
223 
224     /*
225      * If a peer NIC is attached, do not cleanup anything.
226      * Cleanup will happen as a part of qemu_cleanup() -> net_cleanup()
227      * when the guest is shutting down.
228      */
229     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
230         return;
231     }
232     munmap(s->cvq_cmd_out_buffer, vhost_vdpa_net_cvq_cmd_page_len());
233     munmap(s->status, vhost_vdpa_net_cvq_cmd_page_len());
234     if (s->vhost_net) {
235         vhost_net_cleanup(s->vhost_net);
236         g_free(s->vhost_net);
237         s->vhost_net = NULL;
238     }
239      if (s->vhost_vdpa.device_fd >= 0) {
240         qemu_close(s->vhost_vdpa.device_fd);
241         s->vhost_vdpa.device_fd = -1;
242     }
243 }
244 
245 /** Dummy SetSteeringEBPF to support RSS for vhost-vdpa backend  */
246 static bool vhost_vdpa_set_steering_ebpf(NetClientState *nc, int prog_fd)
247 {
248     return true;
249 }
250 
251 static bool vhost_vdpa_has_vnet_hdr(NetClientState *nc)
252 {
253     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
254 
255     return true;
256 }
257 
258 static bool vhost_vdpa_has_ufo(NetClientState *nc)
259 {
260     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
261     VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
262     uint64_t features = 0;
263     features |= (1ULL << VIRTIO_NET_F_HOST_UFO);
264     features = vhost_net_get_features(s->vhost_net, features);
265     return !!(features & (1ULL << VIRTIO_NET_F_HOST_UFO));
266 
267 }
268 
269 static bool vhost_vdpa_check_peer_type(NetClientState *nc, ObjectClass *oc,
270                                        Error **errp)
271 {
272     const char *driver = object_class_get_name(oc);
273 
274     if (!g_str_has_prefix(driver, "virtio-net-")) {
275         error_setg(errp, "vhost-vdpa requires frontend driver virtio-net-*");
276         return false;
277     }
278 
279     return true;
280 }
281 
282 /** Dummy receive in case qemu falls back to userland tap networking */
283 static ssize_t vhost_vdpa_receive(NetClientState *nc, const uint8_t *buf,
284                                   size_t size)
285 {
286     return size;
287 }
288 
289 /** From any vdpa net client, get the netclient of the first queue pair */
290 static VhostVDPAState *vhost_vdpa_net_first_nc_vdpa(VhostVDPAState *s)
291 {
292     NICState *nic = qemu_get_nic(s->nc.peer);
293     NetClientState *nc0 = qemu_get_peer(nic->ncs, 0);
294 
295     return DO_UPCAST(VhostVDPAState, nc, nc0);
296 }
297 
298 static void vhost_vdpa_net_log_global_enable(VhostVDPAState *s, bool enable)
299 {
300     struct vhost_vdpa *v = &s->vhost_vdpa;
301     VirtIONet *n;
302     VirtIODevice *vdev;
303     int data_queue_pairs, cvq, r;
304 
305     /* We are only called on the first data vqs and only if x-svq is not set */
306     if (s->vhost_vdpa.shadow_vqs_enabled == enable) {
307         return;
308     }
309 
310     vdev = v->dev->vdev;
311     n = VIRTIO_NET(vdev);
312     if (!n->vhost_started) {
313         return;
314     }
315 
316     data_queue_pairs = n->multiqueue ? n->max_queue_pairs : 1;
317     cvq = virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) ?
318                                   n->max_ncs - n->max_queue_pairs : 0;
319     /*
320      * TODO: vhost_net_stop does suspend, get_base and reset. We can be smarter
321      * in the future and resume the device if read-only operations between
322      * suspend and reset goes wrong.
323      */
324     vhost_net_stop(vdev, n->nic->ncs, data_queue_pairs, cvq);
325 
326     /* Start will check migration setup_or_active to configure or not SVQ */
327     r = vhost_net_start(vdev, n->nic->ncs, data_queue_pairs, cvq);
328     if (unlikely(r < 0)) {
329         error_report("unable to start vhost net: %s(%d)", g_strerror(-r), -r);
330     }
331 }
332 
333 static void vdpa_net_migration_state_notifier(Notifier *notifier, void *data)
334 {
335     MigrationState *migration = data;
336     VhostVDPAState *s = container_of(notifier, VhostVDPAState,
337                                      migration_state);
338 
339     if (migration_in_setup(migration)) {
340         vhost_vdpa_net_log_global_enable(s, true);
341     } else if (migration_has_failed(migration)) {
342         vhost_vdpa_net_log_global_enable(s, false);
343     }
344 }
345 
346 static void vhost_vdpa_net_data_start_first(VhostVDPAState *s)
347 {
348     struct vhost_vdpa *v = &s->vhost_vdpa;
349 
350     migration_add_notifier(&s->migration_state,
351                            vdpa_net_migration_state_notifier);
352     if (v->shadow_vqs_enabled) {
353         v->iova_tree = vhost_iova_tree_new(v->iova_range.first,
354                                            v->iova_range.last);
355     }
356 }
357 
358 static int vhost_vdpa_net_data_start(NetClientState *nc)
359 {
360     VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
361     struct vhost_vdpa *v = &s->vhost_vdpa;
362 
363     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
364 
365     if (s->always_svq ||
366         migration_is_setup_or_active(migrate_get_current()->state)) {
367         v->shadow_vqs_enabled = true;
368         v->shadow_data = true;
369     } else {
370         v->shadow_vqs_enabled = false;
371         v->shadow_data = false;
372     }
373 
374     if (v->index == 0) {
375         vhost_vdpa_net_data_start_first(s);
376         return 0;
377     }
378 
379     if (v->shadow_vqs_enabled) {
380         VhostVDPAState *s0 = vhost_vdpa_net_first_nc_vdpa(s);
381         v->iova_tree = s0->vhost_vdpa.iova_tree;
382     }
383 
384     return 0;
385 }
386 
387 static int vhost_vdpa_net_data_load(NetClientState *nc)
388 {
389     VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
390     struct vhost_vdpa *v = &s->vhost_vdpa;
391     bool has_cvq = v->dev->vq_index_end % 2;
392 
393     if (has_cvq) {
394         return 0;
395     }
396 
397     for (int i = 0; i < v->dev->nvqs; ++i) {
398         vhost_vdpa_set_vring_ready(v, i + v->dev->vq_index);
399     }
400     return 0;
401 }
402 
403 static void vhost_vdpa_net_client_stop(NetClientState *nc)
404 {
405     VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
406     struct vhost_dev *dev;
407 
408     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
409 
410     if (s->vhost_vdpa.index == 0) {
411         migration_remove_notifier(&s->migration_state);
412     }
413 
414     dev = s->vhost_vdpa.dev;
415     if (dev->vq_index + dev->nvqs == dev->vq_index_end) {
416         g_clear_pointer(&s->vhost_vdpa.iova_tree, vhost_iova_tree_delete);
417     } else {
418         s->vhost_vdpa.iova_tree = NULL;
419     }
420 }
421 
422 static NetClientInfo net_vhost_vdpa_info = {
423         .type = NET_CLIENT_DRIVER_VHOST_VDPA,
424         .size = sizeof(VhostVDPAState),
425         .receive = vhost_vdpa_receive,
426         .start = vhost_vdpa_net_data_start,
427         .load = vhost_vdpa_net_data_load,
428         .stop = vhost_vdpa_net_client_stop,
429         .cleanup = vhost_vdpa_cleanup,
430         .has_vnet_hdr = vhost_vdpa_has_vnet_hdr,
431         .has_ufo = vhost_vdpa_has_ufo,
432         .check_peer_type = vhost_vdpa_check_peer_type,
433         .set_steering_ebpf = vhost_vdpa_set_steering_ebpf,
434 };
435 
436 static int64_t vhost_vdpa_get_vring_group(int device_fd, unsigned vq_index,
437                                           Error **errp)
438 {
439     struct vhost_vring_state state = {
440         .index = vq_index,
441     };
442     int r = ioctl(device_fd, VHOST_VDPA_GET_VRING_GROUP, &state);
443 
444     if (unlikely(r < 0)) {
445         r = -errno;
446         error_setg_errno(errp, errno, "Cannot get VQ %u group", vq_index);
447         return r;
448     }
449 
450     return state.num;
451 }
452 
453 static int vhost_vdpa_set_address_space_id(struct vhost_vdpa *v,
454                                            unsigned vq_group,
455                                            unsigned asid_num)
456 {
457     struct vhost_vring_state asid = {
458         .index = vq_group,
459         .num = asid_num,
460     };
461     int r;
462 
463     r = ioctl(v->device_fd, VHOST_VDPA_SET_GROUP_ASID, &asid);
464     if (unlikely(r < 0)) {
465         error_report("Can't set vq group %u asid %u, errno=%d (%s)",
466                      asid.index, asid.num, errno, g_strerror(errno));
467     }
468     return r;
469 }
470 
471 static void vhost_vdpa_cvq_unmap_buf(struct vhost_vdpa *v, void *addr)
472 {
473     VhostIOVATree *tree = v->iova_tree;
474     DMAMap needle = {
475         /*
476          * No need to specify size or to look for more translations since
477          * this contiguous chunk was allocated by us.
478          */
479         .translated_addr = (hwaddr)(uintptr_t)addr,
480     };
481     const DMAMap *map = vhost_iova_tree_find_iova(tree, &needle);
482     int r;
483 
484     if (unlikely(!map)) {
485         error_report("Cannot locate expected map");
486         return;
487     }
488 
489     r = vhost_vdpa_dma_unmap(v, v->address_space_id, map->iova, map->size + 1);
490     if (unlikely(r != 0)) {
491         error_report("Device cannot unmap: %s(%d)", g_strerror(r), r);
492     }
493 
494     vhost_iova_tree_remove(tree, *map);
495 }
496 
497 /** Map CVQ buffer. */
498 static int vhost_vdpa_cvq_map_buf(struct vhost_vdpa *v, void *buf, size_t size,
499                                   bool write)
500 {
501     DMAMap map = {};
502     int r;
503 
504     map.translated_addr = (hwaddr)(uintptr_t)buf;
505     map.size = size - 1;
506     map.perm = write ? IOMMU_RW : IOMMU_RO,
507     r = vhost_iova_tree_map_alloc(v->iova_tree, &map);
508     if (unlikely(r != IOVA_OK)) {
509         error_report("Cannot map injected element");
510         return r;
511     }
512 
513     r = vhost_vdpa_dma_map(v, v->address_space_id, map.iova,
514                            vhost_vdpa_net_cvq_cmd_page_len(), buf, !write);
515     if (unlikely(r < 0)) {
516         goto dma_map_err;
517     }
518 
519     return 0;
520 
521 dma_map_err:
522     vhost_iova_tree_remove(v->iova_tree, map);
523     return r;
524 }
525 
526 static int vhost_vdpa_net_cvq_start(NetClientState *nc)
527 {
528     VhostVDPAState *s, *s0;
529     struct vhost_vdpa *v;
530     int64_t cvq_group;
531     int r;
532     Error *err = NULL;
533 
534     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
535 
536     s = DO_UPCAST(VhostVDPAState, nc, nc);
537     v = &s->vhost_vdpa;
538 
539     s0 = vhost_vdpa_net_first_nc_vdpa(s);
540     v->shadow_data = s0->vhost_vdpa.shadow_vqs_enabled;
541     v->shadow_vqs_enabled = s0->vhost_vdpa.shadow_vqs_enabled;
542     s->vhost_vdpa.address_space_id = VHOST_VDPA_GUEST_PA_ASID;
543 
544     if (s->vhost_vdpa.shadow_data) {
545         /* SVQ is already configured for all virtqueues */
546         goto out;
547     }
548 
549     /*
550      * If we early return in these cases SVQ will not be enabled. The migration
551      * will be blocked as long as vhost-vdpa backends will not offer _F_LOG.
552      */
553     if (!vhost_vdpa_net_valid_svq_features(v->dev->features, NULL)) {
554         return 0;
555     }
556 
557     if (!s->cvq_isolated) {
558         return 0;
559     }
560 
561     cvq_group = vhost_vdpa_get_vring_group(v->device_fd,
562                                            v->dev->vq_index_end - 1,
563                                            &err);
564     if (unlikely(cvq_group < 0)) {
565         error_report_err(err);
566         return cvq_group;
567     }
568 
569     r = vhost_vdpa_set_address_space_id(v, cvq_group, VHOST_VDPA_NET_CVQ_ASID);
570     if (unlikely(r < 0)) {
571         return r;
572     }
573 
574     v->shadow_vqs_enabled = true;
575     s->vhost_vdpa.address_space_id = VHOST_VDPA_NET_CVQ_ASID;
576 
577 out:
578     if (!s->vhost_vdpa.shadow_vqs_enabled) {
579         return 0;
580     }
581 
582     if (s0->vhost_vdpa.iova_tree) {
583         /*
584          * SVQ is already configured for all virtqueues.  Reuse IOVA tree for
585          * simplicity, whether CVQ shares ASID with guest or not, because:
586          * - Memory listener need access to guest's memory addresses allocated
587          *   in the IOVA tree.
588          * - There should be plenty of IOVA address space for both ASID not to
589          *   worry about collisions between them.  Guest's translations are
590          *   still validated with virtio virtqueue_pop so there is no risk for
591          *   the guest to access memory that it shouldn't.
592          *
593          * To allocate a iova tree per ASID is doable but it complicates the
594          * code and it is not worth it for the moment.
595          */
596         v->iova_tree = s0->vhost_vdpa.iova_tree;
597     } else {
598         v->iova_tree = vhost_iova_tree_new(v->iova_range.first,
599                                            v->iova_range.last);
600     }
601 
602     r = vhost_vdpa_cvq_map_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer,
603                                vhost_vdpa_net_cvq_cmd_page_len(), false);
604     if (unlikely(r < 0)) {
605         return r;
606     }
607 
608     r = vhost_vdpa_cvq_map_buf(&s->vhost_vdpa, s->status,
609                                vhost_vdpa_net_cvq_cmd_page_len(), true);
610     if (unlikely(r < 0)) {
611         vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer);
612     }
613 
614     return r;
615 }
616 
617 static void vhost_vdpa_net_cvq_stop(NetClientState *nc)
618 {
619     VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
620 
621     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
622 
623     if (s->vhost_vdpa.shadow_vqs_enabled) {
624         vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer);
625         vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->status);
626     }
627 
628     vhost_vdpa_net_client_stop(nc);
629 }
630 
631 static ssize_t vhost_vdpa_net_cvq_add(VhostVDPAState *s,
632                                     const struct iovec *out_sg, size_t out_num,
633                                     const struct iovec *in_sg, size_t in_num)
634 {
635     VhostShadowVirtqueue *svq = g_ptr_array_index(s->vhost_vdpa.shadow_vqs, 0);
636     int r;
637 
638     r = vhost_svq_add(svq, out_sg, out_num, in_sg, in_num, NULL);
639     if (unlikely(r != 0)) {
640         if (unlikely(r == -ENOSPC)) {
641             qemu_log_mask(LOG_GUEST_ERROR, "%s: No space on device queue\n",
642                           __func__);
643         }
644     }
645 
646     return r;
647 }
648 
649 /*
650  * Convenience wrapper to poll SVQ for multiple control commands.
651  *
652  * Caller should hold the BQL when invoking this function, and should take
653  * the answer before SVQ pulls by itself when BQL is released.
654  */
655 static ssize_t vhost_vdpa_net_svq_poll(VhostVDPAState *s, size_t cmds_in_flight)
656 {
657     VhostShadowVirtqueue *svq = g_ptr_array_index(s->vhost_vdpa.shadow_vqs, 0);
658     return vhost_svq_poll(svq, cmds_in_flight);
659 }
660 
661 static void vhost_vdpa_net_load_cursor_reset(VhostVDPAState *s,
662                                              struct iovec *out_cursor,
663                                              struct iovec *in_cursor)
664 {
665     /* reset the cursor of the output buffer for the device */
666     out_cursor->iov_base = s->cvq_cmd_out_buffer;
667     out_cursor->iov_len = vhost_vdpa_net_cvq_cmd_page_len();
668 
669     /* reset the cursor of the in buffer for the device */
670     in_cursor->iov_base = s->status;
671     in_cursor->iov_len = vhost_vdpa_net_cvq_cmd_page_len();
672 }
673 
674 /*
675  * Poll SVQ for multiple pending control commands and check the device's ack.
676  *
677  * Caller should hold the BQL when invoking this function.
678  *
679  * @s: The VhostVDPAState
680  * @len: The length of the pending status shadow buffer
681  */
682 static ssize_t vhost_vdpa_net_svq_flush(VhostVDPAState *s, size_t len)
683 {
684     /* device uses a one-byte length ack for each control command */
685     ssize_t dev_written = vhost_vdpa_net_svq_poll(s, len);
686     if (unlikely(dev_written != len)) {
687         return -EIO;
688     }
689 
690     /* check the device's ack */
691     for (int i = 0; i < len; ++i) {
692         if (s->status[i] != VIRTIO_NET_OK) {
693             return -EIO;
694         }
695     }
696     return 0;
697 }
698 
699 static ssize_t vhost_vdpa_net_load_cmd(VhostVDPAState *s,
700                                        struct iovec *out_cursor,
701                                        struct iovec *in_cursor, uint8_t class,
702                                        uint8_t cmd, const struct iovec *data_sg,
703                                        size_t data_num)
704 {
705     const struct virtio_net_ctrl_hdr ctrl = {
706         .class = class,
707         .cmd = cmd,
708     };
709     size_t data_size = iov_size(data_sg, data_num), cmd_size;
710     struct iovec out, in;
711     ssize_t r;
712     unsigned dummy_cursor_iov_cnt;
713     VhostShadowVirtqueue *svq = g_ptr_array_index(s->vhost_vdpa.shadow_vqs, 0);
714 
715     assert(data_size < vhost_vdpa_net_cvq_cmd_page_len() - sizeof(ctrl));
716     cmd_size = sizeof(ctrl) + data_size;
717     if (vhost_svq_available_slots(svq) < 2 ||
718         iov_size(out_cursor, 1) < cmd_size) {
719         /*
720          * It is time to flush all pending control commands if SVQ is full
721          * or control commands shadow buffers are full.
722          *
723          * We can poll here since we've had BQL from the time
724          * we sent the descriptor.
725          */
726         r = vhost_vdpa_net_svq_flush(s, in_cursor->iov_base -
727                                      (void *)s->status);
728         if (unlikely(r < 0)) {
729             return r;
730         }
731 
732         vhost_vdpa_net_load_cursor_reset(s, out_cursor, in_cursor);
733     }
734 
735     /* pack the CVQ command header */
736     iov_from_buf(out_cursor, 1, 0, &ctrl, sizeof(ctrl));
737     /* pack the CVQ command command-specific-data */
738     iov_to_buf(data_sg, data_num, 0,
739                out_cursor->iov_base + sizeof(ctrl), data_size);
740 
741     /* extract the required buffer from the cursor for output */
742     iov_copy(&out, 1, out_cursor, 1, 0, cmd_size);
743     /* extract the required buffer from the cursor for input */
744     iov_copy(&in, 1, in_cursor, 1, 0, sizeof(*s->status));
745 
746     r = vhost_vdpa_net_cvq_add(s, &out, 1, &in, 1);
747     if (unlikely(r < 0)) {
748         return r;
749     }
750 
751     /* iterate the cursors */
752     dummy_cursor_iov_cnt = 1;
753     iov_discard_front(&out_cursor, &dummy_cursor_iov_cnt, cmd_size);
754     dummy_cursor_iov_cnt = 1;
755     iov_discard_front(&in_cursor, &dummy_cursor_iov_cnt, sizeof(*s->status));
756 
757     return 0;
758 }
759 
760 static int vhost_vdpa_net_load_mac(VhostVDPAState *s, const VirtIONet *n,
761                                    struct iovec *out_cursor,
762                                    struct iovec *in_cursor)
763 {
764     if (virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
765         const struct iovec data = {
766             .iov_base = (void *)n->mac,
767             .iov_len = sizeof(n->mac),
768         };
769         ssize_t r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor,
770                                             VIRTIO_NET_CTRL_MAC,
771                                             VIRTIO_NET_CTRL_MAC_ADDR_SET,
772                                             &data, 1);
773         if (unlikely(r < 0)) {
774             return r;
775         }
776     }
777 
778     /*
779      * According to VirtIO standard, "The device MUST have an
780      * empty MAC filtering table on reset.".
781      *
782      * Therefore, there is no need to send this CVQ command if the
783      * driver also sets an empty MAC filter table, which aligns with
784      * the device's defaults.
785      *
786      * Note that the device's defaults can mismatch the driver's
787      * configuration only at live migration.
788      */
789     if (!virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_CTRL_RX) ||
790         n->mac_table.in_use == 0) {
791         return 0;
792     }
793 
794     uint32_t uni_entries = n->mac_table.first_multi,
795              uni_macs_size = uni_entries * ETH_ALEN,
796              mul_entries = n->mac_table.in_use - uni_entries,
797              mul_macs_size = mul_entries * ETH_ALEN;
798     struct virtio_net_ctrl_mac uni = {
799         .entries = cpu_to_le32(uni_entries),
800     };
801     struct virtio_net_ctrl_mac mul = {
802         .entries = cpu_to_le32(mul_entries),
803     };
804     const struct iovec data[] = {
805         {
806             .iov_base = &uni,
807             .iov_len = sizeof(uni),
808         }, {
809             .iov_base = n->mac_table.macs,
810             .iov_len = uni_macs_size,
811         }, {
812             .iov_base = &mul,
813             .iov_len = sizeof(mul),
814         }, {
815             .iov_base = &n->mac_table.macs[uni_macs_size],
816             .iov_len = mul_macs_size,
817         },
818     };
819     ssize_t r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor,
820                                         VIRTIO_NET_CTRL_MAC,
821                                         VIRTIO_NET_CTRL_MAC_TABLE_SET,
822                                         data, ARRAY_SIZE(data));
823     if (unlikely(r < 0)) {
824         return r;
825     }
826 
827     return 0;
828 }
829 
830 static int vhost_vdpa_net_load_rss(VhostVDPAState *s, const VirtIONet *n,
831                                    struct iovec *out_cursor,
832                                    struct iovec *in_cursor, bool do_rss)
833 {
834     struct virtio_net_rss_config cfg = {};
835     ssize_t r;
836     g_autofree uint16_t *table = NULL;
837 
838     /*
839      * According to VirtIO standard, "Initially the device has all hash
840      * types disabled and reports only VIRTIO_NET_HASH_REPORT_NONE.".
841      *
842      * Therefore, there is no need to send this CVQ command if the
843      * driver disables the all hash types, which aligns with
844      * the device's defaults.
845      *
846      * Note that the device's defaults can mismatch the driver's
847      * configuration only at live migration.
848      */
849     if (!n->rss_data.enabled ||
850         n->rss_data.hash_types == VIRTIO_NET_HASH_REPORT_NONE) {
851         return 0;
852     }
853 
854     table = g_malloc_n(n->rss_data.indirections_len,
855                        sizeof(n->rss_data.indirections_table[0]));
856     cfg.hash_types = cpu_to_le32(n->rss_data.hash_types);
857 
858     if (do_rss) {
859         /*
860          * According to VirtIO standard, "Number of entries in indirection_table
861          * is (indirection_table_mask + 1)".
862          */
863         cfg.indirection_table_mask = cpu_to_le16(n->rss_data.indirections_len -
864                                                  1);
865         cfg.unclassified_queue = cpu_to_le16(n->rss_data.default_queue);
866         for (int i = 0; i < n->rss_data.indirections_len; ++i) {
867             table[i] = cpu_to_le16(n->rss_data.indirections_table[i]);
868         }
869         cfg.max_tx_vq = cpu_to_le16(n->curr_queue_pairs);
870     } else {
871         /*
872          * According to VirtIO standard, "Field reserved MUST contain zeroes.
873          * It is defined to make the structure to match the layout of
874          * virtio_net_rss_config structure, defined in 5.1.6.5.7.".
875          *
876          * Therefore, we need to zero the fields in
877          * struct virtio_net_rss_config, which corresponds to the
878          * `reserved` field in struct virtio_net_hash_config.
879          *
880          * Note that all other fields are zeroed at their definitions,
881          * except for the `indirection_table` field, where the actual data
882          * is stored in the `table` variable to ensure compatibility
883          * with RSS case. Therefore, we need to zero the `table` variable here.
884          */
885         table[0] = 0;
886     }
887 
888     /*
889      * Considering that virtio_net_handle_rss() currently does not restore
890      * the hash key length parsed from the CVQ command sent from the guest
891      * into n->rss_data and uses the maximum key length in other code, so
892      * we also employ the maximum key length here.
893      */
894     cfg.hash_key_length = sizeof(n->rss_data.key);
895 
896     const struct iovec data[] = {
897         {
898             .iov_base = &cfg,
899             .iov_len = offsetof(struct virtio_net_rss_config,
900                                 indirection_table),
901         }, {
902             .iov_base = table,
903             .iov_len = n->rss_data.indirections_len *
904                        sizeof(n->rss_data.indirections_table[0]),
905         }, {
906             .iov_base = &cfg.max_tx_vq,
907             .iov_len = offsetof(struct virtio_net_rss_config, hash_key_data) -
908                        offsetof(struct virtio_net_rss_config, max_tx_vq),
909         }, {
910             .iov_base = (void *)n->rss_data.key,
911             .iov_len = sizeof(n->rss_data.key),
912         }
913     };
914 
915     r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor,
916                                 VIRTIO_NET_CTRL_MQ,
917                                 do_rss ? VIRTIO_NET_CTRL_MQ_RSS_CONFIG :
918                                 VIRTIO_NET_CTRL_MQ_HASH_CONFIG,
919                                 data, ARRAY_SIZE(data));
920     if (unlikely(r < 0)) {
921         return r;
922     }
923 
924     return 0;
925 }
926 
927 static int vhost_vdpa_net_load_mq(VhostVDPAState *s,
928                                   const VirtIONet *n,
929                                   struct iovec *out_cursor,
930                                   struct iovec *in_cursor)
931 {
932     struct virtio_net_ctrl_mq mq;
933     ssize_t r;
934 
935     if (!virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_MQ)) {
936         return 0;
937     }
938 
939     mq.virtqueue_pairs = cpu_to_le16(n->curr_queue_pairs);
940     const struct iovec data = {
941         .iov_base = &mq,
942         .iov_len = sizeof(mq),
943     };
944     r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor,
945                                 VIRTIO_NET_CTRL_MQ,
946                                 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET,
947                                 &data, 1);
948     if (unlikely(r < 0)) {
949         return r;
950     }
951 
952     if (virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_RSS)) {
953         /* load the receive-side scaling state */
954         r = vhost_vdpa_net_load_rss(s, n, out_cursor, in_cursor, true);
955         if (unlikely(r < 0)) {
956             return r;
957         }
958     } else if (virtio_vdev_has_feature(&n->parent_obj,
959                                        VIRTIO_NET_F_HASH_REPORT)) {
960         /* load the hash calculation state */
961         r = vhost_vdpa_net_load_rss(s, n, out_cursor, in_cursor, false);
962         if (unlikely(r < 0)) {
963             return r;
964         }
965     }
966 
967     return 0;
968 }
969 
970 static int vhost_vdpa_net_load_offloads(VhostVDPAState *s,
971                                         const VirtIONet *n,
972                                         struct iovec *out_cursor,
973                                         struct iovec *in_cursor)
974 {
975     uint64_t offloads;
976     ssize_t r;
977 
978     if (!virtio_vdev_has_feature(&n->parent_obj,
979                                  VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)) {
980         return 0;
981     }
982 
983     if (n->curr_guest_offloads == virtio_net_supported_guest_offloads(n)) {
984         /*
985          * According to VirtIO standard, "Upon feature negotiation
986          * corresponding offload gets enabled to preserve
987          * backward compatibility.".
988          *
989          * Therefore, there is no need to send this CVQ command if the
990          * driver also enables all supported offloads, which aligns with
991          * the device's defaults.
992          *
993          * Note that the device's defaults can mismatch the driver's
994          * configuration only at live migration.
995          */
996         return 0;
997     }
998 
999     offloads = cpu_to_le64(n->curr_guest_offloads);
1000     const struct iovec data = {
1001         .iov_base = &offloads,
1002         .iov_len = sizeof(offloads),
1003     };
1004     r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor,
1005                                 VIRTIO_NET_CTRL_GUEST_OFFLOADS,
1006                                 VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET,
1007                                 &data, 1);
1008     if (unlikely(r < 0)) {
1009         return r;
1010     }
1011 
1012     return 0;
1013 }
1014 
1015 static int vhost_vdpa_net_load_rx_mode(VhostVDPAState *s,
1016                                        struct iovec *out_cursor,
1017                                        struct iovec *in_cursor,
1018                                        uint8_t cmd,
1019                                        uint8_t on)
1020 {
1021     const struct iovec data = {
1022         .iov_base = &on,
1023         .iov_len = sizeof(on),
1024     };
1025     ssize_t r;
1026 
1027     r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor,
1028                                 VIRTIO_NET_CTRL_RX, cmd, &data, 1);
1029     if (unlikely(r < 0)) {
1030         return r;
1031     }
1032 
1033     return 0;
1034 }
1035 
1036 static int vhost_vdpa_net_load_rx(VhostVDPAState *s,
1037                                   const VirtIONet *n,
1038                                   struct iovec *out_cursor,
1039                                   struct iovec *in_cursor)
1040 {
1041     ssize_t r;
1042 
1043     if (!virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_CTRL_RX)) {
1044         return 0;
1045     }
1046 
1047     /*
1048      * According to virtio_net_reset(), device turns promiscuous mode
1049      * on by default.
1050      *
1051      * Additionally, according to VirtIO standard, "Since there are
1052      * no guarantees, it can use a hash filter or silently switch to
1053      * allmulti or promiscuous mode if it is given too many addresses.".
1054      * QEMU marks `n->mac_table.uni_overflow` if guest sets too many
1055      * non-multicast MAC addresses, indicating that promiscuous mode
1056      * should be enabled.
1057      *
1058      * Therefore, QEMU should only send this CVQ command if the
1059      * `n->mac_table.uni_overflow` is not marked and `n->promisc` is off,
1060      * which sets promiscuous mode on, different from the device's defaults.
1061      *
1062      * Note that the device's defaults can mismatch the driver's
1063      * configuration only at live migration.
1064      */
1065     if (!n->mac_table.uni_overflow && !n->promisc) {
1066         r = vhost_vdpa_net_load_rx_mode(s, out_cursor, in_cursor,
1067                                         VIRTIO_NET_CTRL_RX_PROMISC, 0);
1068         if (unlikely(r < 0)) {
1069             return r;
1070         }
1071     }
1072 
1073     /*
1074      * According to virtio_net_reset(), device turns all-multicast mode
1075      * off by default.
1076      *
1077      * According to VirtIO standard, "Since there are no guarantees,
1078      * it can use a hash filter or silently switch to allmulti or
1079      * promiscuous mode if it is given too many addresses.". QEMU marks
1080      * `n->mac_table.multi_overflow` if guest sets too many
1081      * non-multicast MAC addresses.
1082      *
1083      * Therefore, QEMU should only send this CVQ command if the
1084      * `n->mac_table.multi_overflow` is marked or `n->allmulti` is on,
1085      * which sets all-multicast mode on, different from the device's defaults.
1086      *
1087      * Note that the device's defaults can mismatch the driver's
1088      * configuration only at live migration.
1089      */
1090     if (n->mac_table.multi_overflow || n->allmulti) {
1091         r = vhost_vdpa_net_load_rx_mode(s, out_cursor, in_cursor,
1092                                         VIRTIO_NET_CTRL_RX_ALLMULTI, 1);
1093         if (unlikely(r < 0)) {
1094             return r;
1095         }
1096     }
1097 
1098     if (!virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_CTRL_RX_EXTRA)) {
1099         return 0;
1100     }
1101 
1102     /*
1103      * According to virtio_net_reset(), device turns all-unicast mode
1104      * off by default.
1105      *
1106      * Therefore, QEMU should only send this CVQ command if the driver
1107      * sets all-unicast mode on, different from the device's defaults.
1108      *
1109      * Note that the device's defaults can mismatch the driver's
1110      * configuration only at live migration.
1111      */
1112     if (n->alluni) {
1113         r = vhost_vdpa_net_load_rx_mode(s, out_cursor, in_cursor,
1114                                         VIRTIO_NET_CTRL_RX_ALLUNI, 1);
1115         if (r < 0) {
1116             return r;
1117         }
1118     }
1119 
1120     /*
1121      * According to virtio_net_reset(), device turns non-multicast mode
1122      * off by default.
1123      *
1124      * Therefore, QEMU should only send this CVQ command if the driver
1125      * sets non-multicast mode on, different from the device's defaults.
1126      *
1127      * Note that the device's defaults can mismatch the driver's
1128      * configuration only at live migration.
1129      */
1130     if (n->nomulti) {
1131         r = vhost_vdpa_net_load_rx_mode(s, out_cursor, in_cursor,
1132                                         VIRTIO_NET_CTRL_RX_NOMULTI, 1);
1133         if (r < 0) {
1134             return r;
1135         }
1136     }
1137 
1138     /*
1139      * According to virtio_net_reset(), device turns non-unicast mode
1140      * off by default.
1141      *
1142      * Therefore, QEMU should only send this CVQ command if the driver
1143      * sets non-unicast mode on, different from the device's defaults.
1144      *
1145      * Note that the device's defaults can mismatch the driver's
1146      * configuration only at live migration.
1147      */
1148     if (n->nouni) {
1149         r = vhost_vdpa_net_load_rx_mode(s, out_cursor, in_cursor,
1150                                         VIRTIO_NET_CTRL_RX_NOUNI, 1);
1151         if (r < 0) {
1152             return r;
1153         }
1154     }
1155 
1156     /*
1157      * According to virtio_net_reset(), device turns non-broadcast mode
1158      * off by default.
1159      *
1160      * Therefore, QEMU should only send this CVQ command if the driver
1161      * sets non-broadcast mode on, different from the device's defaults.
1162      *
1163      * Note that the device's defaults can mismatch the driver's
1164      * configuration only at live migration.
1165      */
1166     if (n->nobcast) {
1167         r = vhost_vdpa_net_load_rx_mode(s, out_cursor, in_cursor,
1168                                         VIRTIO_NET_CTRL_RX_NOBCAST, 1);
1169         if (r < 0) {
1170             return r;
1171         }
1172     }
1173 
1174     return 0;
1175 }
1176 
1177 static int vhost_vdpa_net_load_single_vlan(VhostVDPAState *s,
1178                                            const VirtIONet *n,
1179                                            struct iovec *out_cursor,
1180                                            struct iovec *in_cursor,
1181                                            uint16_t vid)
1182 {
1183     const struct iovec data = {
1184         .iov_base = &vid,
1185         .iov_len = sizeof(vid),
1186     };
1187     ssize_t r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor,
1188                                         VIRTIO_NET_CTRL_VLAN,
1189                                         VIRTIO_NET_CTRL_VLAN_ADD,
1190                                         &data, 1);
1191     if (unlikely(r < 0)) {
1192         return r;
1193     }
1194 
1195     return 0;
1196 }
1197 
1198 static int vhost_vdpa_net_load_vlan(VhostVDPAState *s,
1199                                     const VirtIONet *n,
1200                                     struct iovec *out_cursor,
1201                                     struct iovec *in_cursor)
1202 {
1203     int r;
1204 
1205     if (!virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_CTRL_VLAN)) {
1206         return 0;
1207     }
1208 
1209     for (int i = 0; i < MAX_VLAN >> 5; i++) {
1210         for (int j = 0; n->vlans[i] && j <= 0x1f; j++) {
1211             if (n->vlans[i] & (1U << j)) {
1212                 r = vhost_vdpa_net_load_single_vlan(s, n, out_cursor,
1213                                                     in_cursor, (i << 5) + j);
1214                 if (unlikely(r != 0)) {
1215                     return r;
1216                 }
1217             }
1218         }
1219     }
1220 
1221     return 0;
1222 }
1223 
1224 static int vhost_vdpa_net_cvq_load(NetClientState *nc)
1225 {
1226     VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
1227     struct vhost_vdpa *v = &s->vhost_vdpa;
1228     const VirtIONet *n;
1229     int r;
1230     struct iovec out_cursor, in_cursor;
1231 
1232     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
1233 
1234     vhost_vdpa_set_vring_ready(v, v->dev->vq_index);
1235 
1236     if (v->shadow_vqs_enabled) {
1237         n = VIRTIO_NET(v->dev->vdev);
1238         vhost_vdpa_net_load_cursor_reset(s, &out_cursor, &in_cursor);
1239         r = vhost_vdpa_net_load_mac(s, n, &out_cursor, &in_cursor);
1240         if (unlikely(r < 0)) {
1241             return r;
1242         }
1243         r = vhost_vdpa_net_load_mq(s, n, &out_cursor, &in_cursor);
1244         if (unlikely(r)) {
1245             return r;
1246         }
1247         r = vhost_vdpa_net_load_offloads(s, n, &out_cursor, &in_cursor);
1248         if (unlikely(r)) {
1249             return r;
1250         }
1251         r = vhost_vdpa_net_load_rx(s, n, &out_cursor, &in_cursor);
1252         if (unlikely(r)) {
1253             return r;
1254         }
1255         r = vhost_vdpa_net_load_vlan(s, n, &out_cursor, &in_cursor);
1256         if (unlikely(r)) {
1257             return r;
1258         }
1259 
1260         /*
1261          * We need to poll and check all pending device's used buffers.
1262          *
1263          * We can poll here since we've had BQL from the time
1264          * we sent the descriptor.
1265          */
1266         r = vhost_vdpa_net_svq_flush(s, in_cursor.iov_base - (void *)s->status);
1267         if (unlikely(r)) {
1268             return r;
1269         }
1270     }
1271 
1272     for (int i = 0; i < v->dev->vq_index; ++i) {
1273         vhost_vdpa_set_vring_ready(v, i);
1274     }
1275 
1276     return 0;
1277 }
1278 
1279 static NetClientInfo net_vhost_vdpa_cvq_info = {
1280     .type = NET_CLIENT_DRIVER_VHOST_VDPA,
1281     .size = sizeof(VhostVDPAState),
1282     .receive = vhost_vdpa_receive,
1283     .start = vhost_vdpa_net_cvq_start,
1284     .load = vhost_vdpa_net_cvq_load,
1285     .stop = vhost_vdpa_net_cvq_stop,
1286     .cleanup = vhost_vdpa_cleanup,
1287     .has_vnet_hdr = vhost_vdpa_has_vnet_hdr,
1288     .has_ufo = vhost_vdpa_has_ufo,
1289     .check_peer_type = vhost_vdpa_check_peer_type,
1290     .set_steering_ebpf = vhost_vdpa_set_steering_ebpf,
1291 };
1292 
1293 /*
1294  * Forward the excessive VIRTIO_NET_CTRL_MAC_TABLE_SET CVQ command to
1295  * vdpa device.
1296  *
1297  * Considering that QEMU cannot send the entire filter table to the
1298  * vdpa device, it should send the VIRTIO_NET_CTRL_RX_PROMISC CVQ
1299  * command to enable promiscuous mode to receive all packets,
1300  * according to VirtIO standard, "Since there are no guarantees,
1301  * it can use a hash filter or silently switch to allmulti or
1302  * promiscuous mode if it is given too many addresses.".
1303  *
1304  * Since QEMU ignores MAC addresses beyond `MAC_TABLE_ENTRIES` and
1305  * marks `n->mac_table.x_overflow` accordingly, it should have
1306  * the same effect on the device model to receive
1307  * (`MAC_TABLE_ENTRIES` + 1) or more non-multicast MAC addresses.
1308  * The same applies to multicast MAC addresses.
1309  *
1310  * Therefore, QEMU can provide the device model with a fake
1311  * VIRTIO_NET_CTRL_MAC_TABLE_SET command with (`MAC_TABLE_ENTRIES` + 1)
1312  * non-multicast MAC addresses and (`MAC_TABLE_ENTRIES` + 1) multicast
1313  * MAC addresses. This ensures that the device model marks
1314  * `n->mac_table.uni_overflow` and `n->mac_table.multi_overflow`,
1315  * allowing all packets to be received, which aligns with the
1316  * state of the vdpa device.
1317  */
1318 static int vhost_vdpa_net_excessive_mac_filter_cvq_add(VhostVDPAState *s,
1319                                                        VirtQueueElement *elem,
1320                                                        struct iovec *out,
1321                                                        const struct iovec *in)
1322 {
1323     struct virtio_net_ctrl_mac mac_data, *mac_ptr;
1324     struct virtio_net_ctrl_hdr *hdr_ptr;
1325     uint32_t cursor;
1326     ssize_t r;
1327     uint8_t on = 1;
1328 
1329     /* parse the non-multicast MAC address entries from CVQ command */
1330     cursor = sizeof(*hdr_ptr);
1331     r = iov_to_buf(elem->out_sg, elem->out_num, cursor,
1332                    &mac_data, sizeof(mac_data));
1333     if (unlikely(r != sizeof(mac_data))) {
1334         /*
1335          * If the CVQ command is invalid, we should simulate the vdpa device
1336          * to reject the VIRTIO_NET_CTRL_MAC_TABLE_SET CVQ command
1337          */
1338         *s->status = VIRTIO_NET_ERR;
1339         return sizeof(*s->status);
1340     }
1341     cursor += sizeof(mac_data) + le32_to_cpu(mac_data.entries) * ETH_ALEN;
1342 
1343     /* parse the multicast MAC address entries from CVQ command */
1344     r = iov_to_buf(elem->out_sg, elem->out_num, cursor,
1345                    &mac_data, sizeof(mac_data));
1346     if (r != sizeof(mac_data)) {
1347         /*
1348          * If the CVQ command is invalid, we should simulate the vdpa device
1349          * to reject the VIRTIO_NET_CTRL_MAC_TABLE_SET CVQ command
1350          */
1351         *s->status = VIRTIO_NET_ERR;
1352         return sizeof(*s->status);
1353     }
1354     cursor += sizeof(mac_data) + le32_to_cpu(mac_data.entries) * ETH_ALEN;
1355 
1356     /* validate the CVQ command */
1357     if (iov_size(elem->out_sg, elem->out_num) != cursor) {
1358         /*
1359          * If the CVQ command is invalid, we should simulate the vdpa device
1360          * to reject the VIRTIO_NET_CTRL_MAC_TABLE_SET CVQ command
1361          */
1362         *s->status = VIRTIO_NET_ERR;
1363         return sizeof(*s->status);
1364     }
1365 
1366     /*
1367      * According to VirtIO standard, "Since there are no guarantees,
1368      * it can use a hash filter or silently switch to allmulti or
1369      * promiscuous mode if it is given too many addresses.".
1370      *
1371      * Therefore, considering that QEMU is unable to send the entire
1372      * filter table to the vdpa device, it should send the
1373      * VIRTIO_NET_CTRL_RX_PROMISC CVQ command to enable promiscuous mode
1374      */
1375     hdr_ptr = out->iov_base;
1376     out->iov_len = sizeof(*hdr_ptr) + sizeof(on);
1377 
1378     hdr_ptr->class = VIRTIO_NET_CTRL_RX;
1379     hdr_ptr->cmd = VIRTIO_NET_CTRL_RX_PROMISC;
1380     iov_from_buf(out, 1, sizeof(*hdr_ptr), &on, sizeof(on));
1381     r = vhost_vdpa_net_cvq_add(s, out, 1, in, 1);
1382     if (unlikely(r < 0)) {
1383         return r;
1384     }
1385 
1386     /*
1387      * We can poll here since we've had BQL from the time
1388      * we sent the descriptor.
1389      */
1390     r = vhost_vdpa_net_svq_poll(s, 1);
1391     if (unlikely(r < sizeof(*s->status))) {
1392         return r;
1393     }
1394     if (*s->status != VIRTIO_NET_OK) {
1395         return sizeof(*s->status);
1396     }
1397 
1398     /*
1399      * QEMU should also send a fake VIRTIO_NET_CTRL_MAC_TABLE_SET CVQ
1400      * command to the device model, including (`MAC_TABLE_ENTRIES` + 1)
1401      * non-multicast MAC addresses and (`MAC_TABLE_ENTRIES` + 1)
1402      * multicast MAC addresses.
1403      *
1404      * By doing so, the device model can mark `n->mac_table.uni_overflow`
1405      * and `n->mac_table.multi_overflow`, enabling all packets to be
1406      * received, which aligns with the state of the vdpa device.
1407      */
1408     cursor = 0;
1409     uint32_t fake_uni_entries = MAC_TABLE_ENTRIES + 1,
1410              fake_mul_entries = MAC_TABLE_ENTRIES + 1,
1411              fake_cvq_size = sizeof(struct virtio_net_ctrl_hdr) +
1412                              sizeof(mac_data) + fake_uni_entries * ETH_ALEN +
1413                              sizeof(mac_data) + fake_mul_entries * ETH_ALEN;
1414 
1415     assert(fake_cvq_size < vhost_vdpa_net_cvq_cmd_page_len());
1416     out->iov_len = fake_cvq_size;
1417 
1418     /* pack the header for fake CVQ command */
1419     hdr_ptr = out->iov_base + cursor;
1420     hdr_ptr->class = VIRTIO_NET_CTRL_MAC;
1421     hdr_ptr->cmd = VIRTIO_NET_CTRL_MAC_TABLE_SET;
1422     cursor += sizeof(*hdr_ptr);
1423 
1424     /*
1425      * Pack the non-multicast MAC addresses part for fake CVQ command.
1426      *
1427      * According to virtio_net_handle_mac(), QEMU doesn't verify the MAC
1428      * addresses provided in CVQ command. Therefore, only the entries
1429      * field need to be prepared in the CVQ command.
1430      */
1431     mac_ptr = out->iov_base + cursor;
1432     mac_ptr->entries = cpu_to_le32(fake_uni_entries);
1433     cursor += sizeof(*mac_ptr) + fake_uni_entries * ETH_ALEN;
1434 
1435     /*
1436      * Pack the multicast MAC addresses part for fake CVQ command.
1437      *
1438      * According to virtio_net_handle_mac(), QEMU doesn't verify the MAC
1439      * addresses provided in CVQ command. Therefore, only the entries
1440      * field need to be prepared in the CVQ command.
1441      */
1442     mac_ptr = out->iov_base + cursor;
1443     mac_ptr->entries = cpu_to_le32(fake_mul_entries);
1444 
1445     /*
1446      * Simulating QEMU poll a vdpa device used buffer
1447      * for VIRTIO_NET_CTRL_MAC_TABLE_SET CVQ command
1448      */
1449     return sizeof(*s->status);
1450 }
1451 
1452 /**
1453  * Validate and copy control virtqueue commands.
1454  *
1455  * Following QEMU guidelines, we offer a copy of the buffers to the device to
1456  * prevent TOCTOU bugs.
1457  */
1458 static int vhost_vdpa_net_handle_ctrl_avail(VhostShadowVirtqueue *svq,
1459                                             VirtQueueElement *elem,
1460                                             void *opaque)
1461 {
1462     VhostVDPAState *s = opaque;
1463     size_t in_len;
1464     const struct virtio_net_ctrl_hdr *ctrl;
1465     virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
1466     /* Out buffer sent to both the vdpa device and the device model */
1467     struct iovec out = {
1468         .iov_base = s->cvq_cmd_out_buffer,
1469     };
1470     /* in buffer used for device model */
1471     const struct iovec model_in = {
1472         .iov_base = &status,
1473         .iov_len = sizeof(status),
1474     };
1475     /* in buffer used for vdpa device */
1476     const struct iovec vdpa_in = {
1477         .iov_base = s->status,
1478         .iov_len = sizeof(*s->status),
1479     };
1480     ssize_t dev_written = -EINVAL;
1481 
1482     out.iov_len = iov_to_buf(elem->out_sg, elem->out_num, 0,
1483                              s->cvq_cmd_out_buffer,
1484                              vhost_vdpa_net_cvq_cmd_page_len());
1485 
1486     ctrl = s->cvq_cmd_out_buffer;
1487     if (ctrl->class == VIRTIO_NET_CTRL_ANNOUNCE) {
1488         /*
1489          * Guest announce capability is emulated by qemu, so don't forward to
1490          * the device.
1491          */
1492         dev_written = sizeof(status);
1493         *s->status = VIRTIO_NET_OK;
1494     } else if (unlikely(ctrl->class == VIRTIO_NET_CTRL_MAC &&
1495                         ctrl->cmd == VIRTIO_NET_CTRL_MAC_TABLE_SET &&
1496                         iov_size(elem->out_sg, elem->out_num) > out.iov_len)) {
1497         /*
1498          * Due to the size limitation of the out buffer sent to the vdpa device,
1499          * which is determined by vhost_vdpa_net_cvq_cmd_page_len(), excessive
1500          * MAC addresses set by the driver for the filter table can cause
1501          * truncation of the CVQ command in QEMU. As a result, the vdpa device
1502          * rejects the flawed CVQ command.
1503          *
1504          * Therefore, QEMU must handle this situation instead of sending
1505          * the CVQ command directly.
1506          */
1507         dev_written = vhost_vdpa_net_excessive_mac_filter_cvq_add(s, elem,
1508                                                             &out, &vdpa_in);
1509         if (unlikely(dev_written < 0)) {
1510             goto out;
1511         }
1512     } else {
1513         ssize_t r;
1514         r = vhost_vdpa_net_cvq_add(s, &out, 1, &vdpa_in, 1);
1515         if (unlikely(r < 0)) {
1516             dev_written = r;
1517             goto out;
1518         }
1519 
1520         /*
1521          * We can poll here since we've had BQL from the time
1522          * we sent the descriptor.
1523          */
1524         dev_written = vhost_vdpa_net_svq_poll(s, 1);
1525     }
1526 
1527     if (unlikely(dev_written < sizeof(status))) {
1528         error_report("Insufficient written data (%zu)", dev_written);
1529         goto out;
1530     }
1531 
1532     if (*s->status != VIRTIO_NET_OK) {
1533         goto out;
1534     }
1535 
1536     status = VIRTIO_NET_ERR;
1537     virtio_net_handle_ctrl_iov(svq->vdev, &model_in, 1, &out, 1);
1538     if (status != VIRTIO_NET_OK) {
1539         error_report("Bad CVQ processing in model");
1540     }
1541 
1542 out:
1543     in_len = iov_from_buf(elem->in_sg, elem->in_num, 0, &status,
1544                           sizeof(status));
1545     if (unlikely(in_len < sizeof(status))) {
1546         error_report("Bad device CVQ written length");
1547     }
1548     vhost_svq_push_elem(svq, elem, MIN(in_len, sizeof(status)));
1549     /*
1550      * `elem` belongs to vhost_vdpa_net_handle_ctrl_avail() only when
1551      * the function successfully forwards the CVQ command, indicated
1552      * by a non-negative value of `dev_written`. Otherwise, it still
1553      * belongs to SVQ.
1554      * This function should only free the `elem` when it owns.
1555      */
1556     if (dev_written >= 0) {
1557         g_free(elem);
1558     }
1559     return dev_written < 0 ? dev_written : 0;
1560 }
1561 
1562 static const VhostShadowVirtqueueOps vhost_vdpa_net_svq_ops = {
1563     .avail_handler = vhost_vdpa_net_handle_ctrl_avail,
1564 };
1565 
1566 /**
1567  * Probe if CVQ is isolated
1568  *
1569  * @device_fd         The vdpa device fd
1570  * @features          Features offered by the device.
1571  * @cvq_index         The control vq pair index
1572  *
1573  * Returns <0 in case of failure, 0 if false and 1 if true.
1574  */
1575 static int vhost_vdpa_probe_cvq_isolation(int device_fd, uint64_t features,
1576                                           int cvq_index, Error **errp)
1577 {
1578     uint64_t backend_features;
1579     int64_t cvq_group;
1580     uint8_t status = VIRTIO_CONFIG_S_ACKNOWLEDGE |
1581                      VIRTIO_CONFIG_S_DRIVER;
1582     int r;
1583 
1584     ERRP_GUARD();
1585 
1586     r = ioctl(device_fd, VHOST_GET_BACKEND_FEATURES, &backend_features);
1587     if (unlikely(r < 0)) {
1588         error_setg_errno(errp, errno, "Cannot get vdpa backend_features");
1589         return r;
1590     }
1591 
1592     if (!(backend_features & BIT_ULL(VHOST_BACKEND_F_IOTLB_ASID))) {
1593         return 0;
1594     }
1595 
1596     r = ioctl(device_fd, VHOST_VDPA_SET_STATUS, &status);
1597     if (unlikely(r)) {
1598         error_setg_errno(errp, -r, "Cannot set device status");
1599         goto out;
1600     }
1601 
1602     r = ioctl(device_fd, VHOST_SET_FEATURES, &features);
1603     if (unlikely(r)) {
1604         error_setg_errno(errp, -r, "Cannot set features");
1605         goto out;
1606     }
1607 
1608     status |= VIRTIO_CONFIG_S_FEATURES_OK;
1609     r = ioctl(device_fd, VHOST_VDPA_SET_STATUS, &status);
1610     if (unlikely(r)) {
1611         error_setg_errno(errp, -r, "Cannot set device status");
1612         goto out;
1613     }
1614 
1615     cvq_group = vhost_vdpa_get_vring_group(device_fd, cvq_index, errp);
1616     if (unlikely(cvq_group < 0)) {
1617         if (cvq_group != -ENOTSUP) {
1618             r = cvq_group;
1619             goto out;
1620         }
1621 
1622         /*
1623          * The kernel report VHOST_BACKEND_F_IOTLB_ASID if the vdpa frontend
1624          * support ASID even if the parent driver does not.  The CVQ cannot be
1625          * isolated in this case.
1626          */
1627         error_free(*errp);
1628         *errp = NULL;
1629         r = 0;
1630         goto out;
1631     }
1632 
1633     for (int i = 0; i < cvq_index; ++i) {
1634         int64_t group = vhost_vdpa_get_vring_group(device_fd, i, errp);
1635         if (unlikely(group < 0)) {
1636             r = group;
1637             goto out;
1638         }
1639 
1640         if (group == (int64_t)cvq_group) {
1641             r = 0;
1642             goto out;
1643         }
1644     }
1645 
1646     r = 1;
1647 
1648 out:
1649     status = 0;
1650     ioctl(device_fd, VHOST_VDPA_SET_STATUS, &status);
1651     return r;
1652 }
1653 
1654 static NetClientState *net_vhost_vdpa_init(NetClientState *peer,
1655                                        const char *device,
1656                                        const char *name,
1657                                        int vdpa_device_fd,
1658                                        int queue_pair_index,
1659                                        int nvqs,
1660                                        bool is_datapath,
1661                                        bool svq,
1662                                        struct vhost_vdpa_iova_range iova_range,
1663                                        uint64_t features,
1664                                        Error **errp)
1665 {
1666     NetClientState *nc = NULL;
1667     VhostVDPAState *s;
1668     int ret = 0;
1669     assert(name);
1670     int cvq_isolated = 0;
1671 
1672     if (is_datapath) {
1673         nc = qemu_new_net_client(&net_vhost_vdpa_info, peer, device,
1674                                  name);
1675     } else {
1676         cvq_isolated = vhost_vdpa_probe_cvq_isolation(vdpa_device_fd, features,
1677                                                       queue_pair_index * 2,
1678                                                       errp);
1679         if (unlikely(cvq_isolated < 0)) {
1680             return NULL;
1681         }
1682 
1683         nc = qemu_new_net_control_client(&net_vhost_vdpa_cvq_info, peer,
1684                                          device, name);
1685     }
1686     qemu_set_info_str(nc, TYPE_VHOST_VDPA);
1687     s = DO_UPCAST(VhostVDPAState, nc, nc);
1688 
1689     s->vhost_vdpa.device_fd = vdpa_device_fd;
1690     s->vhost_vdpa.index = queue_pair_index;
1691     s->always_svq = svq;
1692     s->migration_state.notify = NULL;
1693     s->vhost_vdpa.shadow_vqs_enabled = svq;
1694     s->vhost_vdpa.iova_range = iova_range;
1695     s->vhost_vdpa.shadow_data = svq;
1696     if (queue_pair_index == 0) {
1697         vhost_vdpa_net_valid_svq_features(features,
1698                                           &s->vhost_vdpa.migration_blocker);
1699     } else if (!is_datapath) {
1700         s->cvq_cmd_out_buffer = mmap(NULL, vhost_vdpa_net_cvq_cmd_page_len(),
1701                                      PROT_READ | PROT_WRITE,
1702                                      MAP_SHARED | MAP_ANONYMOUS, -1, 0);
1703         s->status = mmap(NULL, vhost_vdpa_net_cvq_cmd_page_len(),
1704                          PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS,
1705                          -1, 0);
1706 
1707         s->vhost_vdpa.shadow_vq_ops = &vhost_vdpa_net_svq_ops;
1708         s->vhost_vdpa.shadow_vq_ops_opaque = s;
1709         s->cvq_isolated = cvq_isolated;
1710     }
1711     ret = vhost_vdpa_add(nc, (void *)&s->vhost_vdpa, queue_pair_index, nvqs);
1712     if (ret) {
1713         qemu_del_net_client(nc);
1714         return NULL;
1715     }
1716     return nc;
1717 }
1718 
1719 static int vhost_vdpa_get_features(int fd, uint64_t *features, Error **errp)
1720 {
1721     int ret = ioctl(fd, VHOST_GET_FEATURES, features);
1722     if (unlikely(ret < 0)) {
1723         error_setg_errno(errp, errno,
1724                          "Fail to query features from vhost-vDPA device");
1725     }
1726     return ret;
1727 }
1728 
1729 static int vhost_vdpa_get_max_queue_pairs(int fd, uint64_t features,
1730                                           int *has_cvq, Error **errp)
1731 {
1732     unsigned long config_size = offsetof(struct vhost_vdpa_config, buf);
1733     g_autofree struct vhost_vdpa_config *config = NULL;
1734     __virtio16 *max_queue_pairs;
1735     int ret;
1736 
1737     if (features & (1 << VIRTIO_NET_F_CTRL_VQ)) {
1738         *has_cvq = 1;
1739     } else {
1740         *has_cvq = 0;
1741     }
1742 
1743     if (features & (1 << VIRTIO_NET_F_MQ)) {
1744         config = g_malloc0(config_size + sizeof(*max_queue_pairs));
1745         config->off = offsetof(struct virtio_net_config, max_virtqueue_pairs);
1746         config->len = sizeof(*max_queue_pairs);
1747 
1748         ret = ioctl(fd, VHOST_VDPA_GET_CONFIG, config);
1749         if (ret) {
1750             error_setg(errp, "Fail to get config from vhost-vDPA device");
1751             return -ret;
1752         }
1753 
1754         max_queue_pairs = (__virtio16 *)&config->buf;
1755 
1756         return lduw_le_p(max_queue_pairs);
1757     }
1758 
1759     return 1;
1760 }
1761 
1762 int net_init_vhost_vdpa(const Netdev *netdev, const char *name,
1763                         NetClientState *peer, Error **errp)
1764 {
1765     const NetdevVhostVDPAOptions *opts;
1766     uint64_t features;
1767     int vdpa_device_fd;
1768     g_autofree NetClientState **ncs = NULL;
1769     struct vhost_vdpa_iova_range iova_range;
1770     NetClientState *nc;
1771     int queue_pairs, r, i = 0, has_cvq = 0;
1772 
1773     assert(netdev->type == NET_CLIENT_DRIVER_VHOST_VDPA);
1774     opts = &netdev->u.vhost_vdpa;
1775     if (!opts->vhostdev && !opts->vhostfd) {
1776         error_setg(errp,
1777                    "vhost-vdpa: neither vhostdev= nor vhostfd= was specified");
1778         return -1;
1779     }
1780 
1781     if (opts->vhostdev && opts->vhostfd) {
1782         error_setg(errp,
1783                    "vhost-vdpa: vhostdev= and vhostfd= are mutually exclusive");
1784         return -1;
1785     }
1786 
1787     if (opts->vhostdev) {
1788         vdpa_device_fd = qemu_open(opts->vhostdev, O_RDWR, errp);
1789         if (vdpa_device_fd == -1) {
1790             return -errno;
1791         }
1792     } else {
1793         /* has_vhostfd */
1794         vdpa_device_fd = monitor_fd_param(monitor_cur(), opts->vhostfd, errp);
1795         if (vdpa_device_fd == -1) {
1796             error_prepend(errp, "vhost-vdpa: unable to parse vhostfd: ");
1797             return -1;
1798         }
1799     }
1800 
1801     r = vhost_vdpa_get_features(vdpa_device_fd, &features, errp);
1802     if (unlikely(r < 0)) {
1803         goto err;
1804     }
1805 
1806     queue_pairs = vhost_vdpa_get_max_queue_pairs(vdpa_device_fd, features,
1807                                                  &has_cvq, errp);
1808     if (queue_pairs < 0) {
1809         qemu_close(vdpa_device_fd);
1810         return queue_pairs;
1811     }
1812 
1813     r = vhost_vdpa_get_iova_range(vdpa_device_fd, &iova_range);
1814     if (unlikely(r < 0)) {
1815         error_setg(errp, "vhost-vdpa: get iova range failed: %s",
1816                    strerror(-r));
1817         goto err;
1818     }
1819 
1820     if (opts->x_svq && !vhost_vdpa_net_valid_svq_features(features, errp)) {
1821         goto err;
1822     }
1823 
1824     ncs = g_malloc0(sizeof(*ncs) * queue_pairs);
1825 
1826     for (i = 0; i < queue_pairs; i++) {
1827         ncs[i] = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name,
1828                                      vdpa_device_fd, i, 2, true, opts->x_svq,
1829                                      iova_range, features, errp);
1830         if (!ncs[i])
1831             goto err;
1832     }
1833 
1834     if (has_cvq) {
1835         nc = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name,
1836                                  vdpa_device_fd, i, 1, false,
1837                                  opts->x_svq, iova_range, features, errp);
1838         if (!nc)
1839             goto err;
1840     }
1841 
1842     return 0;
1843 
1844 err:
1845     if (i) {
1846         for (i--; i >= 0; i--) {
1847             qemu_del_net_client(ncs[i]);
1848         }
1849     }
1850 
1851     qemu_close(vdpa_device_fd);
1852 
1853     return -1;
1854 }
1855