xref: /qemu/net/vhost-vdpa.c (revision 77c3a336)
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     NotifierWithReturn 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.index != 0) {
240         return;
241     }
242     qemu_close(s->vhost_vdpa.shared->device_fd);
243     g_free(s->vhost_vdpa.shared);
244 }
245 
246 /** Dummy SetSteeringEBPF to support RSS for vhost-vdpa backend  */
247 static bool vhost_vdpa_set_steering_ebpf(NetClientState *nc, int prog_fd)
248 {
249     return true;
250 }
251 
252 static bool vhost_vdpa_has_vnet_hdr(NetClientState *nc)
253 {
254     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
255 
256     return true;
257 }
258 
259 static bool vhost_vdpa_has_ufo(NetClientState *nc)
260 {
261     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
262     VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
263     uint64_t features = 0;
264     features |= (1ULL << VIRTIO_NET_F_HOST_UFO);
265     features = vhost_net_get_features(s->vhost_net, features);
266     return !!(features & (1ULL << VIRTIO_NET_F_HOST_UFO));
267 
268 }
269 
270 static bool vhost_vdpa_check_peer_type(NetClientState *nc, ObjectClass *oc,
271                                        Error **errp)
272 {
273     const char *driver = object_class_get_name(oc);
274 
275     if (!g_str_has_prefix(driver, "virtio-net-")) {
276         error_setg(errp, "vhost-vdpa requires frontend driver virtio-net-*");
277         return false;
278     }
279 
280     return true;
281 }
282 
283 /** Dummy receive in case qemu falls back to userland tap networking */
284 static ssize_t vhost_vdpa_receive(NetClientState *nc, const uint8_t *buf,
285                                   size_t size)
286 {
287     return size;
288 }
289 
290 
291 /** From any vdpa net client, get the netclient of the i-th queue pair */
292 static VhostVDPAState *vhost_vdpa_net_get_nc_vdpa(VhostVDPAState *s, int i)
293 {
294     NICState *nic = qemu_get_nic(s->nc.peer);
295     NetClientState *nc_i = qemu_get_peer(nic->ncs, i);
296 
297     return DO_UPCAST(VhostVDPAState, nc, nc_i);
298 }
299 
300 static VhostVDPAState *vhost_vdpa_net_first_nc_vdpa(VhostVDPAState *s)
301 {
302     return vhost_vdpa_net_get_nc_vdpa(s, 0);
303 }
304 
305 static void vhost_vdpa_net_log_global_enable(VhostVDPAState *s, bool enable)
306 {
307     struct vhost_vdpa *v = &s->vhost_vdpa;
308     VirtIONet *n;
309     VirtIODevice *vdev;
310     int data_queue_pairs, cvq, r;
311 
312     /* We are only called on the first data vqs and only if x-svq is not set */
313     if (s->vhost_vdpa.shadow_vqs_enabled == enable) {
314         return;
315     }
316 
317     vdev = v->dev->vdev;
318     n = VIRTIO_NET(vdev);
319     if (!n->vhost_started) {
320         return;
321     }
322 
323     data_queue_pairs = n->multiqueue ? n->max_queue_pairs : 1;
324     cvq = virtio_vdev_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) ?
325                                   n->max_ncs - n->max_queue_pairs : 0;
326     /*
327      * TODO: vhost_net_stop does suspend, get_base and reset. We can be smarter
328      * in the future and resume the device if read-only operations between
329      * suspend and reset goes wrong.
330      */
331     vhost_net_stop(vdev, n->nic->ncs, data_queue_pairs, cvq);
332 
333     /* Start will check migration setup_or_active to configure or not SVQ */
334     r = vhost_net_start(vdev, n->nic->ncs, data_queue_pairs, cvq);
335     if (unlikely(r < 0)) {
336         error_report("unable to start vhost net: %s(%d)", g_strerror(-r), -r);
337     }
338 }
339 
340 static int vdpa_net_migration_state_notifier(NotifierWithReturn *notifier,
341                                              MigrationEvent *e, Error **errp)
342 {
343     VhostVDPAState *s = container_of(notifier, VhostVDPAState, migration_state);
344 
345     if (e->type == MIG_EVENT_PRECOPY_SETUP) {
346         vhost_vdpa_net_log_global_enable(s, true);
347     } else if (e->type == MIG_EVENT_PRECOPY_FAILED) {
348         vhost_vdpa_net_log_global_enable(s, false);
349     }
350     return 0;
351 }
352 
353 static void vhost_vdpa_net_data_start_first(VhostVDPAState *s)
354 {
355     struct vhost_vdpa *v = &s->vhost_vdpa;
356 
357     migration_add_notifier(&s->migration_state,
358                            vdpa_net_migration_state_notifier);
359     if (v->shadow_vqs_enabled) {
360         v->shared->iova_tree = vhost_iova_tree_new(v->shared->iova_range.first,
361                                                    v->shared->iova_range.last);
362     }
363 }
364 
365 static int vhost_vdpa_net_data_start(NetClientState *nc)
366 {
367     VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
368     struct vhost_vdpa *v = &s->vhost_vdpa;
369 
370     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
371 
372     if (s->always_svq ||
373         migration_is_setup_or_active(migrate_get_current()->state)) {
374         v->shadow_vqs_enabled = true;
375     } else {
376         v->shadow_vqs_enabled = false;
377     }
378 
379     if (v->index == 0) {
380         v->shared->shadow_data = v->shadow_vqs_enabled;
381         vhost_vdpa_net_data_start_first(s);
382         return 0;
383     }
384 
385     return 0;
386 }
387 
388 static int vhost_vdpa_net_data_load(NetClientState *nc)
389 {
390     VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
391     struct vhost_vdpa *v = &s->vhost_vdpa;
392     bool has_cvq = v->dev->vq_index_end % 2;
393 
394     if (has_cvq) {
395         return 0;
396     }
397 
398     for (int i = 0; i < v->dev->nvqs; ++i) {
399         vhost_vdpa_set_vring_ready(v, i + v->dev->vq_index);
400     }
401     return 0;
402 }
403 
404 static void vhost_vdpa_net_client_stop(NetClientState *nc)
405 {
406     VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
407     struct vhost_dev *dev;
408 
409     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
410 
411     if (s->vhost_vdpa.index == 0) {
412         migration_remove_notifier(&s->migration_state);
413     }
414 
415     dev = s->vhost_vdpa.dev;
416     if (dev->vq_index + dev->nvqs == dev->vq_index_end) {
417         g_clear_pointer(&s->vhost_vdpa.shared->iova_tree,
418                         vhost_iova_tree_delete);
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->shared->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->shared->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->shared, v->address_space_id, map->iova,
490                              map->size + 1);
491     if (unlikely(r != 0)) {
492         error_report("Device cannot unmap: %s(%d)", g_strerror(r), r);
493     }
494 
495     vhost_iova_tree_remove(tree, *map);
496 }
497 
498 /** Map CVQ buffer. */
499 static int vhost_vdpa_cvq_map_buf(struct vhost_vdpa *v, void *buf, size_t size,
500                                   bool write)
501 {
502     DMAMap map = {};
503     int r;
504 
505     map.translated_addr = (hwaddr)(uintptr_t)buf;
506     map.size = size - 1;
507     map.perm = write ? IOMMU_RW : IOMMU_RO,
508     r = vhost_iova_tree_map_alloc(v->shared->iova_tree, &map);
509     if (unlikely(r != IOVA_OK)) {
510         error_report("Cannot map injected element");
511         return r;
512     }
513 
514     r = vhost_vdpa_dma_map(v->shared, v->address_space_id, map.iova,
515                            vhost_vdpa_net_cvq_cmd_page_len(), buf, !write);
516     if (unlikely(r < 0)) {
517         goto dma_map_err;
518     }
519 
520     return 0;
521 
522 dma_map_err:
523     vhost_iova_tree_remove(v->shared->iova_tree, map);
524     return r;
525 }
526 
527 static int vhost_vdpa_net_cvq_start(NetClientState *nc)
528 {
529     VhostVDPAState *s, *s0;
530     struct vhost_vdpa *v;
531     int64_t cvq_group;
532     int r;
533     Error *err = NULL;
534 
535     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
536 
537     s = DO_UPCAST(VhostVDPAState, nc, nc);
538     v = &s->vhost_vdpa;
539 
540     s0 = vhost_vdpa_net_first_nc_vdpa(s);
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 (v->shared->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->shared->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     /*
583      * If other vhost_vdpa already have an iova_tree, reuse it for simplicity,
584      * whether CVQ shares ASID with guest or not, because:
585      * - Memory listener need access to guest's memory addresses allocated in
586      *   the IOVA tree.
587      * - There should be plenty of IOVA address space for both ASID not to
588      *   worry about collisions between them.  Guest's translations are still
589      *   validated with virtio virtqueue_pop so there is no risk for the guest
590      *   to access memory that it shouldn't.
591      *
592      * To allocate a iova tree per ASID is doable but it complicates the code
593      * and it is not worth it for the moment.
594      */
595     if (!v->shared->iova_tree) {
596         v->shared->iova_tree = vhost_iova_tree_new(v->shared->iova_range.first,
597                                                    v->shared->iova_range.last);
598     }
599 
600     r = vhost_vdpa_cvq_map_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer,
601                                vhost_vdpa_net_cvq_cmd_page_len(), false);
602     if (unlikely(r < 0)) {
603         return r;
604     }
605 
606     r = vhost_vdpa_cvq_map_buf(&s->vhost_vdpa, s->status,
607                                vhost_vdpa_net_cvq_cmd_page_len(), true);
608     if (unlikely(r < 0)) {
609         vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer);
610     }
611 
612     return r;
613 }
614 
615 static void vhost_vdpa_net_cvq_stop(NetClientState *nc)
616 {
617     VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
618 
619     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
620 
621     if (s->vhost_vdpa.shadow_vqs_enabled) {
622         vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->cvq_cmd_out_buffer);
623         vhost_vdpa_cvq_unmap_buf(&s->vhost_vdpa, s->status);
624     }
625 
626     vhost_vdpa_net_client_stop(nc);
627 }
628 
629 static ssize_t vhost_vdpa_net_cvq_add(VhostVDPAState *s,
630                                     const struct iovec *out_sg, size_t out_num,
631                                     const struct iovec *in_sg, size_t in_num)
632 {
633     VhostShadowVirtqueue *svq = g_ptr_array_index(s->vhost_vdpa.shadow_vqs, 0);
634     int r;
635 
636     r = vhost_svq_add(svq, out_sg, out_num, in_sg, in_num, NULL);
637     if (unlikely(r != 0)) {
638         if (unlikely(r == -ENOSPC)) {
639             qemu_log_mask(LOG_GUEST_ERROR, "%s: No space on device queue\n",
640                           __func__);
641         }
642     }
643 
644     return r;
645 }
646 
647 /*
648  * Convenience wrapper to poll SVQ for multiple control commands.
649  *
650  * Caller should hold the BQL when invoking this function, and should take
651  * the answer before SVQ pulls by itself when BQL is released.
652  */
653 static ssize_t vhost_vdpa_net_svq_poll(VhostVDPAState *s, size_t cmds_in_flight)
654 {
655     VhostShadowVirtqueue *svq = g_ptr_array_index(s->vhost_vdpa.shadow_vqs, 0);
656     return vhost_svq_poll(svq, cmds_in_flight);
657 }
658 
659 static void vhost_vdpa_net_load_cursor_reset(VhostVDPAState *s,
660                                              struct iovec *out_cursor,
661                                              struct iovec *in_cursor)
662 {
663     /* reset the cursor of the output buffer for the device */
664     out_cursor->iov_base = s->cvq_cmd_out_buffer;
665     out_cursor->iov_len = vhost_vdpa_net_cvq_cmd_page_len();
666 
667     /* reset the cursor of the in buffer for the device */
668     in_cursor->iov_base = s->status;
669     in_cursor->iov_len = vhost_vdpa_net_cvq_cmd_page_len();
670 }
671 
672 /*
673  * Poll SVQ for multiple pending control commands and check the device's ack.
674  *
675  * Caller should hold the BQL when invoking this function.
676  *
677  * @s: The VhostVDPAState
678  * @len: The length of the pending status shadow buffer
679  */
680 static ssize_t vhost_vdpa_net_svq_flush(VhostVDPAState *s, size_t len)
681 {
682     /* device uses a one-byte length ack for each control command */
683     ssize_t dev_written = vhost_vdpa_net_svq_poll(s, len);
684     if (unlikely(dev_written != len)) {
685         return -EIO;
686     }
687 
688     /* check the device's ack */
689     for (int i = 0; i < len; ++i) {
690         if (s->status[i] != VIRTIO_NET_OK) {
691             return -EIO;
692         }
693     }
694     return 0;
695 }
696 
697 static ssize_t vhost_vdpa_net_load_cmd(VhostVDPAState *s,
698                                        struct iovec *out_cursor,
699                                        struct iovec *in_cursor, uint8_t class,
700                                        uint8_t cmd, const struct iovec *data_sg,
701                                        size_t data_num)
702 {
703     const struct virtio_net_ctrl_hdr ctrl = {
704         .class = class,
705         .cmd = cmd,
706     };
707     size_t data_size = iov_size(data_sg, data_num), cmd_size;
708     struct iovec out, in;
709     ssize_t r;
710     unsigned dummy_cursor_iov_cnt;
711     VhostShadowVirtqueue *svq = g_ptr_array_index(s->vhost_vdpa.shadow_vqs, 0);
712 
713     assert(data_size < vhost_vdpa_net_cvq_cmd_page_len() - sizeof(ctrl));
714     cmd_size = sizeof(ctrl) + data_size;
715     if (vhost_svq_available_slots(svq) < 2 ||
716         iov_size(out_cursor, 1) < cmd_size) {
717         /*
718          * It is time to flush all pending control commands if SVQ is full
719          * or control commands shadow buffers are full.
720          *
721          * We can poll here since we've had BQL from the time
722          * we sent the descriptor.
723          */
724         r = vhost_vdpa_net_svq_flush(s, in_cursor->iov_base -
725                                      (void *)s->status);
726         if (unlikely(r < 0)) {
727             return r;
728         }
729 
730         vhost_vdpa_net_load_cursor_reset(s, out_cursor, in_cursor);
731     }
732 
733     /* pack the CVQ command header */
734     iov_from_buf(out_cursor, 1, 0, &ctrl, sizeof(ctrl));
735     /* pack the CVQ command command-specific-data */
736     iov_to_buf(data_sg, data_num, 0,
737                out_cursor->iov_base + sizeof(ctrl), data_size);
738 
739     /* extract the required buffer from the cursor for output */
740     iov_copy(&out, 1, out_cursor, 1, 0, cmd_size);
741     /* extract the required buffer from the cursor for input */
742     iov_copy(&in, 1, in_cursor, 1, 0, sizeof(*s->status));
743 
744     r = vhost_vdpa_net_cvq_add(s, &out, 1, &in, 1);
745     if (unlikely(r < 0)) {
746         return r;
747     }
748 
749     /* iterate the cursors */
750     dummy_cursor_iov_cnt = 1;
751     iov_discard_front(&out_cursor, &dummy_cursor_iov_cnt, cmd_size);
752     dummy_cursor_iov_cnt = 1;
753     iov_discard_front(&in_cursor, &dummy_cursor_iov_cnt, sizeof(*s->status));
754 
755     return 0;
756 }
757 
758 static int vhost_vdpa_net_load_mac(VhostVDPAState *s, const VirtIONet *n,
759                                    struct iovec *out_cursor,
760                                    struct iovec *in_cursor)
761 {
762     if (virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
763         const struct iovec data = {
764             .iov_base = (void *)n->mac,
765             .iov_len = sizeof(n->mac),
766         };
767         ssize_t r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor,
768                                             VIRTIO_NET_CTRL_MAC,
769                                             VIRTIO_NET_CTRL_MAC_ADDR_SET,
770                                             &data, 1);
771         if (unlikely(r < 0)) {
772             return r;
773         }
774     }
775 
776     /*
777      * According to VirtIO standard, "The device MUST have an
778      * empty MAC filtering table on reset.".
779      *
780      * Therefore, there is no need to send this CVQ command if the
781      * driver also sets an empty MAC filter table, which aligns with
782      * the device's defaults.
783      *
784      * Note that the device's defaults can mismatch the driver's
785      * configuration only at live migration.
786      */
787     if (!virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_CTRL_RX) ||
788         n->mac_table.in_use == 0) {
789         return 0;
790     }
791 
792     uint32_t uni_entries = n->mac_table.first_multi,
793              uni_macs_size = uni_entries * ETH_ALEN,
794              mul_entries = n->mac_table.in_use - uni_entries,
795              mul_macs_size = mul_entries * ETH_ALEN;
796     struct virtio_net_ctrl_mac uni = {
797         .entries = cpu_to_le32(uni_entries),
798     };
799     struct virtio_net_ctrl_mac mul = {
800         .entries = cpu_to_le32(mul_entries),
801     };
802     const struct iovec data[] = {
803         {
804             .iov_base = &uni,
805             .iov_len = sizeof(uni),
806         }, {
807             .iov_base = n->mac_table.macs,
808             .iov_len = uni_macs_size,
809         }, {
810             .iov_base = &mul,
811             .iov_len = sizeof(mul),
812         }, {
813             .iov_base = &n->mac_table.macs[uni_macs_size],
814             .iov_len = mul_macs_size,
815         },
816     };
817     ssize_t r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor,
818                                         VIRTIO_NET_CTRL_MAC,
819                                         VIRTIO_NET_CTRL_MAC_TABLE_SET,
820                                         data, ARRAY_SIZE(data));
821     if (unlikely(r < 0)) {
822         return r;
823     }
824 
825     return 0;
826 }
827 
828 static int vhost_vdpa_net_load_rss(VhostVDPAState *s, const VirtIONet *n,
829                                    struct iovec *out_cursor,
830                                    struct iovec *in_cursor, bool do_rss)
831 {
832     struct virtio_net_rss_config cfg = {};
833     ssize_t r;
834     g_autofree uint16_t *table = NULL;
835 
836     /*
837      * According to VirtIO standard, "Initially the device has all hash
838      * types disabled and reports only VIRTIO_NET_HASH_REPORT_NONE.".
839      *
840      * Therefore, there is no need to send this CVQ command if the
841      * driver disables the all hash types, which aligns with
842      * the device's defaults.
843      *
844      * Note that the device's defaults can mismatch the driver's
845      * configuration only at live migration.
846      */
847     if (!n->rss_data.enabled ||
848         n->rss_data.hash_types == VIRTIO_NET_HASH_REPORT_NONE) {
849         return 0;
850     }
851 
852     table = g_malloc_n(n->rss_data.indirections_len,
853                        sizeof(n->rss_data.indirections_table[0]));
854     cfg.hash_types = cpu_to_le32(n->rss_data.hash_types);
855 
856     if (do_rss) {
857         /*
858          * According to VirtIO standard, "Number of entries in indirection_table
859          * is (indirection_table_mask + 1)".
860          */
861         cfg.indirection_table_mask = cpu_to_le16(n->rss_data.indirections_len -
862                                                  1);
863         cfg.unclassified_queue = cpu_to_le16(n->rss_data.default_queue);
864         for (int i = 0; i < n->rss_data.indirections_len; ++i) {
865             table[i] = cpu_to_le16(n->rss_data.indirections_table[i]);
866         }
867         cfg.max_tx_vq = cpu_to_le16(n->curr_queue_pairs);
868     } else {
869         /*
870          * According to VirtIO standard, "Field reserved MUST contain zeroes.
871          * It is defined to make the structure to match the layout of
872          * virtio_net_rss_config structure, defined in 5.1.6.5.7.".
873          *
874          * Therefore, we need to zero the fields in
875          * struct virtio_net_rss_config, which corresponds to the
876          * `reserved` field in struct virtio_net_hash_config.
877          *
878          * Note that all other fields are zeroed at their definitions,
879          * except for the `indirection_table` field, where the actual data
880          * is stored in the `table` variable to ensure compatibility
881          * with RSS case. Therefore, we need to zero the `table` variable here.
882          */
883         table[0] = 0;
884     }
885 
886     /*
887      * Considering that virtio_net_handle_rss() currently does not restore
888      * the hash key length parsed from the CVQ command sent from the guest
889      * into n->rss_data and uses the maximum key length in other code, so
890      * we also employ the maximum key length here.
891      */
892     cfg.hash_key_length = sizeof(n->rss_data.key);
893 
894     const struct iovec data[] = {
895         {
896             .iov_base = &cfg,
897             .iov_len = offsetof(struct virtio_net_rss_config,
898                                 indirection_table),
899         }, {
900             .iov_base = table,
901             .iov_len = n->rss_data.indirections_len *
902                        sizeof(n->rss_data.indirections_table[0]),
903         }, {
904             .iov_base = &cfg.max_tx_vq,
905             .iov_len = offsetof(struct virtio_net_rss_config, hash_key_data) -
906                        offsetof(struct virtio_net_rss_config, max_tx_vq),
907         }, {
908             .iov_base = (void *)n->rss_data.key,
909             .iov_len = sizeof(n->rss_data.key),
910         }
911     };
912 
913     r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor,
914                                 VIRTIO_NET_CTRL_MQ,
915                                 do_rss ? VIRTIO_NET_CTRL_MQ_RSS_CONFIG :
916                                 VIRTIO_NET_CTRL_MQ_HASH_CONFIG,
917                                 data, ARRAY_SIZE(data));
918     if (unlikely(r < 0)) {
919         return r;
920     }
921 
922     return 0;
923 }
924 
925 static int vhost_vdpa_net_load_mq(VhostVDPAState *s,
926                                   const VirtIONet *n,
927                                   struct iovec *out_cursor,
928                                   struct iovec *in_cursor)
929 {
930     struct virtio_net_ctrl_mq mq;
931     ssize_t r;
932 
933     if (!virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_MQ)) {
934         return 0;
935     }
936 
937     mq.virtqueue_pairs = cpu_to_le16(n->curr_queue_pairs);
938     const struct iovec data = {
939         .iov_base = &mq,
940         .iov_len = sizeof(mq),
941     };
942     r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor,
943                                 VIRTIO_NET_CTRL_MQ,
944                                 VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET,
945                                 &data, 1);
946     if (unlikely(r < 0)) {
947         return r;
948     }
949 
950     if (virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_RSS)) {
951         /* load the receive-side scaling state */
952         r = vhost_vdpa_net_load_rss(s, n, out_cursor, in_cursor, true);
953         if (unlikely(r < 0)) {
954             return r;
955         }
956     } else if (virtio_vdev_has_feature(&n->parent_obj,
957                                        VIRTIO_NET_F_HASH_REPORT)) {
958         /* load the hash calculation state */
959         r = vhost_vdpa_net_load_rss(s, n, out_cursor, in_cursor, false);
960         if (unlikely(r < 0)) {
961             return r;
962         }
963     }
964 
965     return 0;
966 }
967 
968 static int vhost_vdpa_net_load_offloads(VhostVDPAState *s,
969                                         const VirtIONet *n,
970                                         struct iovec *out_cursor,
971                                         struct iovec *in_cursor)
972 {
973     uint64_t offloads;
974     ssize_t r;
975 
976     if (!virtio_vdev_has_feature(&n->parent_obj,
977                                  VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)) {
978         return 0;
979     }
980 
981     if (n->curr_guest_offloads == virtio_net_supported_guest_offloads(n)) {
982         /*
983          * According to VirtIO standard, "Upon feature negotiation
984          * corresponding offload gets enabled to preserve
985          * backward compatibility.".
986          *
987          * Therefore, there is no need to send this CVQ command if the
988          * driver also enables all supported offloads, which aligns with
989          * the device's defaults.
990          *
991          * Note that the device's defaults can mismatch the driver's
992          * configuration only at live migration.
993          */
994         return 0;
995     }
996 
997     offloads = cpu_to_le64(n->curr_guest_offloads);
998     const struct iovec data = {
999         .iov_base = &offloads,
1000         .iov_len = sizeof(offloads),
1001     };
1002     r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor,
1003                                 VIRTIO_NET_CTRL_GUEST_OFFLOADS,
1004                                 VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET,
1005                                 &data, 1);
1006     if (unlikely(r < 0)) {
1007         return r;
1008     }
1009 
1010     return 0;
1011 }
1012 
1013 static int vhost_vdpa_net_load_rx_mode(VhostVDPAState *s,
1014                                        struct iovec *out_cursor,
1015                                        struct iovec *in_cursor,
1016                                        uint8_t cmd,
1017                                        uint8_t on)
1018 {
1019     const struct iovec data = {
1020         .iov_base = &on,
1021         .iov_len = sizeof(on),
1022     };
1023     ssize_t r;
1024 
1025     r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor,
1026                                 VIRTIO_NET_CTRL_RX, cmd, &data, 1);
1027     if (unlikely(r < 0)) {
1028         return r;
1029     }
1030 
1031     return 0;
1032 }
1033 
1034 static int vhost_vdpa_net_load_rx(VhostVDPAState *s,
1035                                   const VirtIONet *n,
1036                                   struct iovec *out_cursor,
1037                                   struct iovec *in_cursor)
1038 {
1039     ssize_t r;
1040 
1041     if (!virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_CTRL_RX)) {
1042         return 0;
1043     }
1044 
1045     /*
1046      * According to virtio_net_reset(), device turns promiscuous mode
1047      * on by default.
1048      *
1049      * Additionally, according to VirtIO standard, "Since there are
1050      * no guarantees, it can use a hash filter or silently switch to
1051      * allmulti or promiscuous mode if it is given too many addresses.".
1052      * QEMU marks `n->mac_table.uni_overflow` if guest sets too many
1053      * non-multicast MAC addresses, indicating that promiscuous mode
1054      * should be enabled.
1055      *
1056      * Therefore, QEMU should only send this CVQ command if the
1057      * `n->mac_table.uni_overflow` is not marked and `n->promisc` is off,
1058      * which sets promiscuous mode on, different from the device's defaults.
1059      *
1060      * Note that the device's defaults can mismatch the driver's
1061      * configuration only at live migration.
1062      */
1063     if (!n->mac_table.uni_overflow && !n->promisc) {
1064         r = vhost_vdpa_net_load_rx_mode(s, out_cursor, in_cursor,
1065                                         VIRTIO_NET_CTRL_RX_PROMISC, 0);
1066         if (unlikely(r < 0)) {
1067             return r;
1068         }
1069     }
1070 
1071     /*
1072      * According to virtio_net_reset(), device turns all-multicast mode
1073      * off by default.
1074      *
1075      * According to VirtIO standard, "Since there are no guarantees,
1076      * it can use a hash filter or silently switch to allmulti or
1077      * promiscuous mode if it is given too many addresses.". QEMU marks
1078      * `n->mac_table.multi_overflow` if guest sets too many
1079      * non-multicast MAC addresses.
1080      *
1081      * Therefore, QEMU should only send this CVQ command if the
1082      * `n->mac_table.multi_overflow` is marked or `n->allmulti` is on,
1083      * which sets all-multicast mode on, different from the device's defaults.
1084      *
1085      * Note that the device's defaults can mismatch the driver's
1086      * configuration only at live migration.
1087      */
1088     if (n->mac_table.multi_overflow || n->allmulti) {
1089         r = vhost_vdpa_net_load_rx_mode(s, out_cursor, in_cursor,
1090                                         VIRTIO_NET_CTRL_RX_ALLMULTI, 1);
1091         if (unlikely(r < 0)) {
1092             return r;
1093         }
1094     }
1095 
1096     if (!virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_CTRL_RX_EXTRA)) {
1097         return 0;
1098     }
1099 
1100     /*
1101      * According to virtio_net_reset(), device turns all-unicast mode
1102      * off by default.
1103      *
1104      * Therefore, QEMU should only send this CVQ command if the driver
1105      * sets all-unicast mode on, different from the device's defaults.
1106      *
1107      * Note that the device's defaults can mismatch the driver's
1108      * configuration only at live migration.
1109      */
1110     if (n->alluni) {
1111         r = vhost_vdpa_net_load_rx_mode(s, out_cursor, in_cursor,
1112                                         VIRTIO_NET_CTRL_RX_ALLUNI, 1);
1113         if (r < 0) {
1114             return r;
1115         }
1116     }
1117 
1118     /*
1119      * According to virtio_net_reset(), device turns non-multicast mode
1120      * off by default.
1121      *
1122      * Therefore, QEMU should only send this CVQ command if the driver
1123      * sets non-multicast mode on, different from the device's defaults.
1124      *
1125      * Note that the device's defaults can mismatch the driver's
1126      * configuration only at live migration.
1127      */
1128     if (n->nomulti) {
1129         r = vhost_vdpa_net_load_rx_mode(s, out_cursor, in_cursor,
1130                                         VIRTIO_NET_CTRL_RX_NOMULTI, 1);
1131         if (r < 0) {
1132             return r;
1133         }
1134     }
1135 
1136     /*
1137      * According to virtio_net_reset(), device turns non-unicast mode
1138      * off by default.
1139      *
1140      * Therefore, QEMU should only send this CVQ command if the driver
1141      * sets non-unicast mode on, different from the device's defaults.
1142      *
1143      * Note that the device's defaults can mismatch the driver's
1144      * configuration only at live migration.
1145      */
1146     if (n->nouni) {
1147         r = vhost_vdpa_net_load_rx_mode(s, out_cursor, in_cursor,
1148                                         VIRTIO_NET_CTRL_RX_NOUNI, 1);
1149         if (r < 0) {
1150             return r;
1151         }
1152     }
1153 
1154     /*
1155      * According to virtio_net_reset(), device turns non-broadcast mode
1156      * off by default.
1157      *
1158      * Therefore, QEMU should only send this CVQ command if the driver
1159      * sets non-broadcast mode on, different from the device's defaults.
1160      *
1161      * Note that the device's defaults can mismatch the driver's
1162      * configuration only at live migration.
1163      */
1164     if (n->nobcast) {
1165         r = vhost_vdpa_net_load_rx_mode(s, out_cursor, in_cursor,
1166                                         VIRTIO_NET_CTRL_RX_NOBCAST, 1);
1167         if (r < 0) {
1168             return r;
1169         }
1170     }
1171 
1172     return 0;
1173 }
1174 
1175 static int vhost_vdpa_net_load_single_vlan(VhostVDPAState *s,
1176                                            const VirtIONet *n,
1177                                            struct iovec *out_cursor,
1178                                            struct iovec *in_cursor,
1179                                            uint16_t vid)
1180 {
1181     const struct iovec data = {
1182         .iov_base = &vid,
1183         .iov_len = sizeof(vid),
1184     };
1185     ssize_t r = vhost_vdpa_net_load_cmd(s, out_cursor, in_cursor,
1186                                         VIRTIO_NET_CTRL_VLAN,
1187                                         VIRTIO_NET_CTRL_VLAN_ADD,
1188                                         &data, 1);
1189     if (unlikely(r < 0)) {
1190         return r;
1191     }
1192 
1193     return 0;
1194 }
1195 
1196 static int vhost_vdpa_net_load_vlan(VhostVDPAState *s,
1197                                     const VirtIONet *n,
1198                                     struct iovec *out_cursor,
1199                                     struct iovec *in_cursor)
1200 {
1201     int r;
1202 
1203     if (!virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_CTRL_VLAN)) {
1204         return 0;
1205     }
1206 
1207     for (int i = 0; i < MAX_VLAN >> 5; i++) {
1208         for (int j = 0; n->vlans[i] && j <= 0x1f; j++) {
1209             if (n->vlans[i] & (1U << j)) {
1210                 r = vhost_vdpa_net_load_single_vlan(s, n, out_cursor,
1211                                                     in_cursor, (i << 5) + j);
1212                 if (unlikely(r != 0)) {
1213                     return r;
1214                 }
1215             }
1216         }
1217     }
1218 
1219     return 0;
1220 }
1221 
1222 static int vhost_vdpa_net_cvq_load(NetClientState *nc)
1223 {
1224     VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
1225     struct vhost_vdpa *v = &s->vhost_vdpa;
1226     const VirtIONet *n;
1227     int r;
1228     struct iovec out_cursor, in_cursor;
1229 
1230     assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
1231 
1232     vhost_vdpa_set_vring_ready(v, v->dev->vq_index);
1233 
1234     if (v->shadow_vqs_enabled) {
1235         n = VIRTIO_NET(v->dev->vdev);
1236         vhost_vdpa_net_load_cursor_reset(s, &out_cursor, &in_cursor);
1237         r = vhost_vdpa_net_load_mac(s, n, &out_cursor, &in_cursor);
1238         if (unlikely(r < 0)) {
1239             return r;
1240         }
1241         r = vhost_vdpa_net_load_mq(s, n, &out_cursor, &in_cursor);
1242         if (unlikely(r)) {
1243             return r;
1244         }
1245         r = vhost_vdpa_net_load_offloads(s, n, &out_cursor, &in_cursor);
1246         if (unlikely(r)) {
1247             return r;
1248         }
1249         r = vhost_vdpa_net_load_rx(s, n, &out_cursor, &in_cursor);
1250         if (unlikely(r)) {
1251             return r;
1252         }
1253         r = vhost_vdpa_net_load_vlan(s, n, &out_cursor, &in_cursor);
1254         if (unlikely(r)) {
1255             return r;
1256         }
1257 
1258         /*
1259          * We need to poll and check all pending device's used buffers.
1260          *
1261          * We can poll here since we've had BQL from the time
1262          * we sent the descriptor.
1263          */
1264         r = vhost_vdpa_net_svq_flush(s, in_cursor.iov_base - (void *)s->status);
1265         if (unlikely(r)) {
1266             return r;
1267         }
1268     }
1269 
1270     for (int i = 0; i < v->dev->vq_index; ++i) {
1271         vhost_vdpa_set_vring_ready(v, i);
1272     }
1273 
1274     return 0;
1275 }
1276 
1277 static NetClientInfo net_vhost_vdpa_cvq_info = {
1278     .type = NET_CLIENT_DRIVER_VHOST_VDPA,
1279     .size = sizeof(VhostVDPAState),
1280     .receive = vhost_vdpa_receive,
1281     .start = vhost_vdpa_net_cvq_start,
1282     .load = vhost_vdpa_net_cvq_load,
1283     .stop = vhost_vdpa_net_cvq_stop,
1284     .cleanup = vhost_vdpa_cleanup,
1285     .has_vnet_hdr = vhost_vdpa_has_vnet_hdr,
1286     .has_ufo = vhost_vdpa_has_ufo,
1287     .check_peer_type = vhost_vdpa_check_peer_type,
1288     .set_steering_ebpf = vhost_vdpa_set_steering_ebpf,
1289 };
1290 
1291 /*
1292  * Forward the excessive VIRTIO_NET_CTRL_MAC_TABLE_SET CVQ command to
1293  * vdpa device.
1294  *
1295  * Considering that QEMU cannot send the entire filter table to the
1296  * vdpa device, it should send the VIRTIO_NET_CTRL_RX_PROMISC CVQ
1297  * command to enable promiscuous mode to receive all packets,
1298  * according to VirtIO standard, "Since there are no guarantees,
1299  * it can use a hash filter or silently switch to allmulti or
1300  * promiscuous mode if it is given too many addresses.".
1301  *
1302  * Since QEMU ignores MAC addresses beyond `MAC_TABLE_ENTRIES` and
1303  * marks `n->mac_table.x_overflow` accordingly, it should have
1304  * the same effect on the device model to receive
1305  * (`MAC_TABLE_ENTRIES` + 1) or more non-multicast MAC addresses.
1306  * The same applies to multicast MAC addresses.
1307  *
1308  * Therefore, QEMU can provide the device model with a fake
1309  * VIRTIO_NET_CTRL_MAC_TABLE_SET command with (`MAC_TABLE_ENTRIES` + 1)
1310  * non-multicast MAC addresses and (`MAC_TABLE_ENTRIES` + 1) multicast
1311  * MAC addresses. This ensures that the device model marks
1312  * `n->mac_table.uni_overflow` and `n->mac_table.multi_overflow`,
1313  * allowing all packets to be received, which aligns with the
1314  * state of the vdpa device.
1315  */
1316 static int vhost_vdpa_net_excessive_mac_filter_cvq_add(VhostVDPAState *s,
1317                                                        VirtQueueElement *elem,
1318                                                        struct iovec *out,
1319                                                        const struct iovec *in)
1320 {
1321     struct virtio_net_ctrl_mac mac_data, *mac_ptr;
1322     struct virtio_net_ctrl_hdr *hdr_ptr;
1323     uint32_t cursor;
1324     ssize_t r;
1325     uint8_t on = 1;
1326 
1327     /* parse the non-multicast MAC address entries from CVQ command */
1328     cursor = sizeof(*hdr_ptr);
1329     r = iov_to_buf(elem->out_sg, elem->out_num, cursor,
1330                    &mac_data, sizeof(mac_data));
1331     if (unlikely(r != sizeof(mac_data))) {
1332         /*
1333          * If the CVQ command is invalid, we should simulate the vdpa device
1334          * to reject the VIRTIO_NET_CTRL_MAC_TABLE_SET CVQ command
1335          */
1336         *s->status = VIRTIO_NET_ERR;
1337         return sizeof(*s->status);
1338     }
1339     cursor += sizeof(mac_data) + le32_to_cpu(mac_data.entries) * ETH_ALEN;
1340 
1341     /* parse the multicast MAC address entries from CVQ command */
1342     r = iov_to_buf(elem->out_sg, elem->out_num, cursor,
1343                    &mac_data, sizeof(mac_data));
1344     if (r != sizeof(mac_data)) {
1345         /*
1346          * If the CVQ command is invalid, we should simulate the vdpa device
1347          * to reject the VIRTIO_NET_CTRL_MAC_TABLE_SET CVQ command
1348          */
1349         *s->status = VIRTIO_NET_ERR;
1350         return sizeof(*s->status);
1351     }
1352     cursor += sizeof(mac_data) + le32_to_cpu(mac_data.entries) * ETH_ALEN;
1353 
1354     /* validate the CVQ command */
1355     if (iov_size(elem->out_sg, elem->out_num) != cursor) {
1356         /*
1357          * If the CVQ command is invalid, we should simulate the vdpa device
1358          * to reject the VIRTIO_NET_CTRL_MAC_TABLE_SET CVQ command
1359          */
1360         *s->status = VIRTIO_NET_ERR;
1361         return sizeof(*s->status);
1362     }
1363 
1364     /*
1365      * According to VirtIO standard, "Since there are no guarantees,
1366      * it can use a hash filter or silently switch to allmulti or
1367      * promiscuous mode if it is given too many addresses.".
1368      *
1369      * Therefore, considering that QEMU is unable to send the entire
1370      * filter table to the vdpa device, it should send the
1371      * VIRTIO_NET_CTRL_RX_PROMISC CVQ command to enable promiscuous mode
1372      */
1373     hdr_ptr = out->iov_base;
1374     out->iov_len = sizeof(*hdr_ptr) + sizeof(on);
1375 
1376     hdr_ptr->class = VIRTIO_NET_CTRL_RX;
1377     hdr_ptr->cmd = VIRTIO_NET_CTRL_RX_PROMISC;
1378     iov_from_buf(out, 1, sizeof(*hdr_ptr), &on, sizeof(on));
1379     r = vhost_vdpa_net_cvq_add(s, out, 1, in, 1);
1380     if (unlikely(r < 0)) {
1381         return r;
1382     }
1383 
1384     /*
1385      * We can poll here since we've had BQL from the time
1386      * we sent the descriptor.
1387      */
1388     r = vhost_vdpa_net_svq_poll(s, 1);
1389     if (unlikely(r < sizeof(*s->status))) {
1390         return r;
1391     }
1392     if (*s->status != VIRTIO_NET_OK) {
1393         return sizeof(*s->status);
1394     }
1395 
1396     /*
1397      * QEMU should also send a fake VIRTIO_NET_CTRL_MAC_TABLE_SET CVQ
1398      * command to the device model, including (`MAC_TABLE_ENTRIES` + 1)
1399      * non-multicast MAC addresses and (`MAC_TABLE_ENTRIES` + 1)
1400      * multicast MAC addresses.
1401      *
1402      * By doing so, the device model can mark `n->mac_table.uni_overflow`
1403      * and `n->mac_table.multi_overflow`, enabling all packets to be
1404      * received, which aligns with the state of the vdpa device.
1405      */
1406     cursor = 0;
1407     uint32_t fake_uni_entries = MAC_TABLE_ENTRIES + 1,
1408              fake_mul_entries = MAC_TABLE_ENTRIES + 1,
1409              fake_cvq_size = sizeof(struct virtio_net_ctrl_hdr) +
1410                              sizeof(mac_data) + fake_uni_entries * ETH_ALEN +
1411                              sizeof(mac_data) + fake_mul_entries * ETH_ALEN;
1412 
1413     assert(fake_cvq_size < vhost_vdpa_net_cvq_cmd_page_len());
1414     out->iov_len = fake_cvq_size;
1415 
1416     /* pack the header for fake CVQ command */
1417     hdr_ptr = out->iov_base + cursor;
1418     hdr_ptr->class = VIRTIO_NET_CTRL_MAC;
1419     hdr_ptr->cmd = VIRTIO_NET_CTRL_MAC_TABLE_SET;
1420     cursor += sizeof(*hdr_ptr);
1421 
1422     /*
1423      * Pack the non-multicast MAC addresses part for fake CVQ command.
1424      *
1425      * According to virtio_net_handle_mac(), QEMU doesn't verify the MAC
1426      * addresses provided in CVQ command. Therefore, only the entries
1427      * field need to be prepared in the CVQ command.
1428      */
1429     mac_ptr = out->iov_base + cursor;
1430     mac_ptr->entries = cpu_to_le32(fake_uni_entries);
1431     cursor += sizeof(*mac_ptr) + fake_uni_entries * ETH_ALEN;
1432 
1433     /*
1434      * Pack the multicast MAC addresses part for fake CVQ command.
1435      *
1436      * According to virtio_net_handle_mac(), QEMU doesn't verify the MAC
1437      * addresses provided in CVQ command. Therefore, only the entries
1438      * field need to be prepared in the CVQ command.
1439      */
1440     mac_ptr = out->iov_base + cursor;
1441     mac_ptr->entries = cpu_to_le32(fake_mul_entries);
1442 
1443     /*
1444      * Simulating QEMU poll a vdpa device used buffer
1445      * for VIRTIO_NET_CTRL_MAC_TABLE_SET CVQ command
1446      */
1447     return sizeof(*s->status);
1448 }
1449 
1450 /**
1451  * Validate and copy control virtqueue commands.
1452  *
1453  * Following QEMU guidelines, we offer a copy of the buffers to the device to
1454  * prevent TOCTOU bugs.
1455  */
1456 static int vhost_vdpa_net_handle_ctrl_avail(VhostShadowVirtqueue *svq,
1457                                             VirtQueueElement *elem,
1458                                             void *opaque)
1459 {
1460     VhostVDPAState *s = opaque;
1461     size_t in_len;
1462     const struct virtio_net_ctrl_hdr *ctrl;
1463     virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
1464     /* Out buffer sent to both the vdpa device and the device model */
1465     struct iovec out = {
1466         .iov_base = s->cvq_cmd_out_buffer,
1467     };
1468     /* in buffer used for device model */
1469     const struct iovec model_in = {
1470         .iov_base = &status,
1471         .iov_len = sizeof(status),
1472     };
1473     /* in buffer used for vdpa device */
1474     const struct iovec vdpa_in = {
1475         .iov_base = s->status,
1476         .iov_len = sizeof(*s->status),
1477     };
1478     ssize_t dev_written = -EINVAL;
1479 
1480     out.iov_len = iov_to_buf(elem->out_sg, elem->out_num, 0,
1481                              s->cvq_cmd_out_buffer,
1482                              vhost_vdpa_net_cvq_cmd_page_len());
1483 
1484     ctrl = s->cvq_cmd_out_buffer;
1485     if (ctrl->class == VIRTIO_NET_CTRL_ANNOUNCE) {
1486         /*
1487          * Guest announce capability is emulated by qemu, so don't forward to
1488          * the device.
1489          */
1490         dev_written = sizeof(status);
1491         *s->status = VIRTIO_NET_OK;
1492     } else if (unlikely(ctrl->class == VIRTIO_NET_CTRL_MAC &&
1493                         ctrl->cmd == VIRTIO_NET_CTRL_MAC_TABLE_SET &&
1494                         iov_size(elem->out_sg, elem->out_num) > out.iov_len)) {
1495         /*
1496          * Due to the size limitation of the out buffer sent to the vdpa device,
1497          * which is determined by vhost_vdpa_net_cvq_cmd_page_len(), excessive
1498          * MAC addresses set by the driver for the filter table can cause
1499          * truncation of the CVQ command in QEMU. As a result, the vdpa device
1500          * rejects the flawed CVQ command.
1501          *
1502          * Therefore, QEMU must handle this situation instead of sending
1503          * the CVQ command directly.
1504          */
1505         dev_written = vhost_vdpa_net_excessive_mac_filter_cvq_add(s, elem,
1506                                                             &out, &vdpa_in);
1507         if (unlikely(dev_written < 0)) {
1508             goto out;
1509         }
1510     } else {
1511         ssize_t r;
1512         r = vhost_vdpa_net_cvq_add(s, &out, 1, &vdpa_in, 1);
1513         if (unlikely(r < 0)) {
1514             dev_written = r;
1515             goto out;
1516         }
1517 
1518         /*
1519          * We can poll here since we've had BQL from the time
1520          * we sent the descriptor.
1521          */
1522         dev_written = vhost_vdpa_net_svq_poll(s, 1);
1523     }
1524 
1525     if (unlikely(dev_written < sizeof(status))) {
1526         error_report("Insufficient written data (%zu)", dev_written);
1527         goto out;
1528     }
1529 
1530     if (*s->status != VIRTIO_NET_OK) {
1531         goto out;
1532     }
1533 
1534     status = VIRTIO_NET_ERR;
1535     virtio_net_handle_ctrl_iov(svq->vdev, &model_in, 1, &out, 1);
1536     if (status != VIRTIO_NET_OK) {
1537         error_report("Bad CVQ processing in model");
1538     }
1539 
1540 out:
1541     in_len = iov_from_buf(elem->in_sg, elem->in_num, 0, &status,
1542                           sizeof(status));
1543     if (unlikely(in_len < sizeof(status))) {
1544         error_report("Bad device CVQ written length");
1545     }
1546     vhost_svq_push_elem(svq, elem, MIN(in_len, sizeof(status)));
1547     /*
1548      * `elem` belongs to vhost_vdpa_net_handle_ctrl_avail() only when
1549      * the function successfully forwards the CVQ command, indicated
1550      * by a non-negative value of `dev_written`. Otherwise, it still
1551      * belongs to SVQ.
1552      * This function should only free the `elem` when it owns.
1553      */
1554     if (dev_written >= 0) {
1555         g_free(elem);
1556     }
1557     return dev_written < 0 ? dev_written : 0;
1558 }
1559 
1560 static const VhostShadowVirtqueueOps vhost_vdpa_net_svq_ops = {
1561     .avail_handler = vhost_vdpa_net_handle_ctrl_avail,
1562 };
1563 
1564 /**
1565  * Probe if CVQ is isolated
1566  *
1567  * @device_fd         The vdpa device fd
1568  * @features          Features offered by the device.
1569  * @cvq_index         The control vq pair index
1570  *
1571  * Returns <0 in case of failure, 0 if false and 1 if true.
1572  */
1573 static int vhost_vdpa_probe_cvq_isolation(int device_fd, uint64_t features,
1574                                           int cvq_index, Error **errp)
1575 {
1576     uint64_t backend_features;
1577     int64_t cvq_group;
1578     uint8_t status = VIRTIO_CONFIG_S_ACKNOWLEDGE |
1579                      VIRTIO_CONFIG_S_DRIVER;
1580     int r;
1581 
1582     ERRP_GUARD();
1583 
1584     r = ioctl(device_fd, VHOST_GET_BACKEND_FEATURES, &backend_features);
1585     if (unlikely(r < 0)) {
1586         error_setg_errno(errp, errno, "Cannot get vdpa backend_features");
1587         return r;
1588     }
1589 
1590     if (!(backend_features & BIT_ULL(VHOST_BACKEND_F_IOTLB_ASID))) {
1591         return 0;
1592     }
1593 
1594     r = ioctl(device_fd, VHOST_VDPA_SET_STATUS, &status);
1595     if (unlikely(r)) {
1596         error_setg_errno(errp, -r, "Cannot set device status");
1597         goto out;
1598     }
1599 
1600     r = ioctl(device_fd, VHOST_SET_FEATURES, &features);
1601     if (unlikely(r)) {
1602         error_setg_errno(errp, -r, "Cannot set features");
1603         goto out;
1604     }
1605 
1606     status |= VIRTIO_CONFIG_S_FEATURES_OK;
1607     r = ioctl(device_fd, VHOST_VDPA_SET_STATUS, &status);
1608     if (unlikely(r)) {
1609         error_setg_errno(errp, -r, "Cannot set device status");
1610         goto out;
1611     }
1612 
1613     cvq_group = vhost_vdpa_get_vring_group(device_fd, cvq_index, errp);
1614     if (unlikely(cvq_group < 0)) {
1615         if (cvq_group != -ENOTSUP) {
1616             r = cvq_group;
1617             goto out;
1618         }
1619 
1620         /*
1621          * The kernel report VHOST_BACKEND_F_IOTLB_ASID if the vdpa frontend
1622          * support ASID even if the parent driver does not.  The CVQ cannot be
1623          * isolated in this case.
1624          */
1625         error_free(*errp);
1626         *errp = NULL;
1627         r = 0;
1628         goto out;
1629     }
1630 
1631     for (int i = 0; i < cvq_index; ++i) {
1632         int64_t group = vhost_vdpa_get_vring_group(device_fd, i, errp);
1633         if (unlikely(group < 0)) {
1634             r = group;
1635             goto out;
1636         }
1637 
1638         if (group == (int64_t)cvq_group) {
1639             r = 0;
1640             goto out;
1641         }
1642     }
1643 
1644     r = 1;
1645 
1646 out:
1647     status = 0;
1648     ioctl(device_fd, VHOST_VDPA_SET_STATUS, &status);
1649     return r;
1650 }
1651 
1652 static NetClientState *net_vhost_vdpa_init(NetClientState *peer,
1653                                        const char *device,
1654                                        const char *name,
1655                                        int vdpa_device_fd,
1656                                        int queue_pair_index,
1657                                        int nvqs,
1658                                        bool is_datapath,
1659                                        bool svq,
1660                                        struct vhost_vdpa_iova_range iova_range,
1661                                        uint64_t features,
1662                                        VhostVDPAShared *shared,
1663                                        Error **errp)
1664 {
1665     NetClientState *nc = NULL;
1666     VhostVDPAState *s;
1667     int ret = 0;
1668     assert(name);
1669     int cvq_isolated = 0;
1670 
1671     if (is_datapath) {
1672         nc = qemu_new_net_client(&net_vhost_vdpa_info, peer, device,
1673                                  name);
1674     } else {
1675         cvq_isolated = vhost_vdpa_probe_cvq_isolation(vdpa_device_fd, features,
1676                                                       queue_pair_index * 2,
1677                                                       errp);
1678         if (unlikely(cvq_isolated < 0)) {
1679             return NULL;
1680         }
1681 
1682         nc = qemu_new_net_control_client(&net_vhost_vdpa_cvq_info, peer,
1683                                          device, name);
1684     }
1685     qemu_set_info_str(nc, TYPE_VHOST_VDPA);
1686     s = DO_UPCAST(VhostVDPAState, nc, nc);
1687 
1688     s->vhost_vdpa.index = queue_pair_index;
1689     s->always_svq = svq;
1690     s->migration_state.notify = NULL;
1691     s->vhost_vdpa.shadow_vqs_enabled = svq;
1692     if (queue_pair_index == 0) {
1693         vhost_vdpa_net_valid_svq_features(features,
1694                                           &s->vhost_vdpa.migration_blocker);
1695         s->vhost_vdpa.shared = g_new0(VhostVDPAShared, 1);
1696         s->vhost_vdpa.shared->device_fd = vdpa_device_fd;
1697         s->vhost_vdpa.shared->iova_range = iova_range;
1698         s->vhost_vdpa.shared->shadow_data = svq;
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     if (queue_pair_index != 0) {
1712         s->vhost_vdpa.shared = shared;
1713     }
1714 
1715     ret = vhost_vdpa_add(nc, (void *)&s->vhost_vdpa, queue_pair_index, nvqs);
1716     if (ret) {
1717         qemu_del_net_client(nc);
1718         return NULL;
1719     }
1720 
1721     return nc;
1722 }
1723 
1724 static int vhost_vdpa_get_features(int fd, uint64_t *features, Error **errp)
1725 {
1726     int ret = ioctl(fd, VHOST_GET_FEATURES, features);
1727     if (unlikely(ret < 0)) {
1728         error_setg_errno(errp, errno,
1729                          "Fail to query features from vhost-vDPA device");
1730     }
1731     return ret;
1732 }
1733 
1734 static int vhost_vdpa_get_max_queue_pairs(int fd, uint64_t features,
1735                                           int *has_cvq, Error **errp)
1736 {
1737     unsigned long config_size = offsetof(struct vhost_vdpa_config, buf);
1738     g_autofree struct vhost_vdpa_config *config = NULL;
1739     __virtio16 *max_queue_pairs;
1740     int ret;
1741 
1742     if (features & (1 << VIRTIO_NET_F_CTRL_VQ)) {
1743         *has_cvq = 1;
1744     } else {
1745         *has_cvq = 0;
1746     }
1747 
1748     if (features & (1 << VIRTIO_NET_F_MQ)) {
1749         config = g_malloc0(config_size + sizeof(*max_queue_pairs));
1750         config->off = offsetof(struct virtio_net_config, max_virtqueue_pairs);
1751         config->len = sizeof(*max_queue_pairs);
1752 
1753         ret = ioctl(fd, VHOST_VDPA_GET_CONFIG, config);
1754         if (ret) {
1755             error_setg(errp, "Fail to get config from vhost-vDPA device");
1756             return -ret;
1757         }
1758 
1759         max_queue_pairs = (__virtio16 *)&config->buf;
1760 
1761         return lduw_le_p(max_queue_pairs);
1762     }
1763 
1764     return 1;
1765 }
1766 
1767 int net_init_vhost_vdpa(const Netdev *netdev, const char *name,
1768                         NetClientState *peer, Error **errp)
1769 {
1770     const NetdevVhostVDPAOptions *opts;
1771     uint64_t features;
1772     int vdpa_device_fd;
1773     g_autofree NetClientState **ncs = NULL;
1774     struct vhost_vdpa_iova_range iova_range;
1775     NetClientState *nc;
1776     int queue_pairs, r, i = 0, has_cvq = 0;
1777 
1778     assert(netdev->type == NET_CLIENT_DRIVER_VHOST_VDPA);
1779     opts = &netdev->u.vhost_vdpa;
1780     if (!opts->vhostdev && !opts->vhostfd) {
1781         error_setg(errp,
1782                    "vhost-vdpa: neither vhostdev= nor vhostfd= was specified");
1783         return -1;
1784     }
1785 
1786     if (opts->vhostdev && opts->vhostfd) {
1787         error_setg(errp,
1788                    "vhost-vdpa: vhostdev= and vhostfd= are mutually exclusive");
1789         return -1;
1790     }
1791 
1792     if (opts->vhostdev) {
1793         vdpa_device_fd = qemu_open(opts->vhostdev, O_RDWR, errp);
1794         if (vdpa_device_fd == -1) {
1795             return -errno;
1796         }
1797     } else {
1798         /* has_vhostfd */
1799         vdpa_device_fd = monitor_fd_param(monitor_cur(), opts->vhostfd, errp);
1800         if (vdpa_device_fd == -1) {
1801             error_prepend(errp, "vhost-vdpa: unable to parse vhostfd: ");
1802             return -1;
1803         }
1804     }
1805 
1806     r = vhost_vdpa_get_features(vdpa_device_fd, &features, errp);
1807     if (unlikely(r < 0)) {
1808         goto err;
1809     }
1810 
1811     queue_pairs = vhost_vdpa_get_max_queue_pairs(vdpa_device_fd, features,
1812                                                  &has_cvq, errp);
1813     if (queue_pairs < 0) {
1814         qemu_close(vdpa_device_fd);
1815         return queue_pairs;
1816     }
1817 
1818     r = vhost_vdpa_get_iova_range(vdpa_device_fd, &iova_range);
1819     if (unlikely(r < 0)) {
1820         error_setg(errp, "vhost-vdpa: get iova range failed: %s",
1821                    strerror(-r));
1822         goto err;
1823     }
1824 
1825     if (opts->x_svq && !vhost_vdpa_net_valid_svq_features(features, errp)) {
1826         goto err;
1827     }
1828 
1829     ncs = g_malloc0(sizeof(*ncs) * queue_pairs);
1830 
1831     for (i = 0; i < queue_pairs; i++) {
1832         VhostVDPAShared *shared = NULL;
1833 
1834         if (i) {
1835             shared = DO_UPCAST(VhostVDPAState, nc, ncs[0])->vhost_vdpa.shared;
1836         }
1837         ncs[i] = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name,
1838                                      vdpa_device_fd, i, 2, true, opts->x_svq,
1839                                      iova_range, features, shared, errp);
1840         if (!ncs[i])
1841             goto err;
1842     }
1843 
1844     if (has_cvq) {
1845         VhostVDPAState *s0 = DO_UPCAST(VhostVDPAState, nc, ncs[0]);
1846         VhostVDPAShared *shared = s0->vhost_vdpa.shared;
1847 
1848         nc = net_vhost_vdpa_init(peer, TYPE_VHOST_VDPA, name,
1849                                  vdpa_device_fd, i, 1, false,
1850                                  opts->x_svq, iova_range, features, shared,
1851                                  errp);
1852         if (!nc)
1853             goto err;
1854     }
1855 
1856     return 0;
1857 
1858 err:
1859     if (i) {
1860         for (i--; i >= 0; i--) {
1861             qemu_del_net_client(ncs[i]);
1862         }
1863     }
1864 
1865     qemu_close(vdpa_device_fd);
1866 
1867     return -1;
1868 }
1869