xref: /qemu/hw/virtio/vhost-user.c (revision 856dfd8a)
1 /*
2  * vhost-user
3  *
4  * Copyright (c) 2013 Virtual Open Systems Sarl.
5  *
6  * This work is licensed under the terms of the GNU GPL, version 2 or later.
7  * See the COPYING file in the top-level directory.
8  *
9  */
10 
11 #include "qemu/osdep.h"
12 #include "qapi/error.h"
13 #include "hw/virtio/vhost.h"
14 #include "hw/virtio/vhost-user.h"
15 #include "hw/virtio/vhost-backend.h"
16 #include "hw/virtio/virtio.h"
17 #include "hw/virtio/virtio-net.h"
18 #include "chardev/char-fe.h"
19 #include "sysemu/kvm.h"
20 #include "qemu/error-report.h"
21 #include "qemu/sockets.h"
22 #include "sysemu/cryptodev.h"
23 #include "migration/migration.h"
24 #include "migration/postcopy-ram.h"
25 #include "trace.h"
26 
27 #include <sys/ioctl.h>
28 #include <sys/socket.h>
29 #include <sys/un.h>
30 
31 #include "standard-headers/linux/vhost_types.h"
32 
33 #ifdef CONFIG_LINUX
34 #include <linux/userfaultfd.h>
35 #endif
36 
37 #define VHOST_MEMORY_MAX_NREGIONS    8
38 #define VHOST_USER_F_PROTOCOL_FEATURES 30
39 #define VHOST_USER_SLAVE_MAX_FDS     8
40 
41 /*
42  * Maximum size of virtio device config space
43  */
44 #define VHOST_USER_MAX_CONFIG_SIZE 256
45 
46 enum VhostUserProtocolFeature {
47     VHOST_USER_PROTOCOL_F_MQ = 0,
48     VHOST_USER_PROTOCOL_F_LOG_SHMFD = 1,
49     VHOST_USER_PROTOCOL_F_RARP = 2,
50     VHOST_USER_PROTOCOL_F_REPLY_ACK = 3,
51     VHOST_USER_PROTOCOL_F_NET_MTU = 4,
52     VHOST_USER_PROTOCOL_F_SLAVE_REQ = 5,
53     VHOST_USER_PROTOCOL_F_CROSS_ENDIAN = 6,
54     VHOST_USER_PROTOCOL_F_CRYPTO_SESSION = 7,
55     VHOST_USER_PROTOCOL_F_PAGEFAULT = 8,
56     VHOST_USER_PROTOCOL_F_CONFIG = 9,
57     VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD = 10,
58     VHOST_USER_PROTOCOL_F_HOST_NOTIFIER = 11,
59     VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD = 12,
60     VHOST_USER_PROTOCOL_F_MAX
61 };
62 
63 #define VHOST_USER_PROTOCOL_FEATURE_MASK ((1 << VHOST_USER_PROTOCOL_F_MAX) - 1)
64 
65 typedef enum VhostUserRequest {
66     VHOST_USER_NONE = 0,
67     VHOST_USER_GET_FEATURES = 1,
68     VHOST_USER_SET_FEATURES = 2,
69     VHOST_USER_SET_OWNER = 3,
70     VHOST_USER_RESET_OWNER = 4,
71     VHOST_USER_SET_MEM_TABLE = 5,
72     VHOST_USER_SET_LOG_BASE = 6,
73     VHOST_USER_SET_LOG_FD = 7,
74     VHOST_USER_SET_VRING_NUM = 8,
75     VHOST_USER_SET_VRING_ADDR = 9,
76     VHOST_USER_SET_VRING_BASE = 10,
77     VHOST_USER_GET_VRING_BASE = 11,
78     VHOST_USER_SET_VRING_KICK = 12,
79     VHOST_USER_SET_VRING_CALL = 13,
80     VHOST_USER_SET_VRING_ERR = 14,
81     VHOST_USER_GET_PROTOCOL_FEATURES = 15,
82     VHOST_USER_SET_PROTOCOL_FEATURES = 16,
83     VHOST_USER_GET_QUEUE_NUM = 17,
84     VHOST_USER_SET_VRING_ENABLE = 18,
85     VHOST_USER_SEND_RARP = 19,
86     VHOST_USER_NET_SET_MTU = 20,
87     VHOST_USER_SET_SLAVE_REQ_FD = 21,
88     VHOST_USER_IOTLB_MSG = 22,
89     VHOST_USER_SET_VRING_ENDIAN = 23,
90     VHOST_USER_GET_CONFIG = 24,
91     VHOST_USER_SET_CONFIG = 25,
92     VHOST_USER_CREATE_CRYPTO_SESSION = 26,
93     VHOST_USER_CLOSE_CRYPTO_SESSION = 27,
94     VHOST_USER_POSTCOPY_ADVISE  = 28,
95     VHOST_USER_POSTCOPY_LISTEN  = 29,
96     VHOST_USER_POSTCOPY_END     = 30,
97     VHOST_USER_GET_INFLIGHT_FD = 31,
98     VHOST_USER_SET_INFLIGHT_FD = 32,
99     VHOST_USER_GPU_SET_SOCKET = 33,
100     VHOST_USER_MAX
101 } VhostUserRequest;
102 
103 typedef enum VhostUserSlaveRequest {
104     VHOST_USER_SLAVE_NONE = 0,
105     VHOST_USER_SLAVE_IOTLB_MSG = 1,
106     VHOST_USER_SLAVE_CONFIG_CHANGE_MSG = 2,
107     VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = 3,
108     VHOST_USER_SLAVE_MAX
109 }  VhostUserSlaveRequest;
110 
111 typedef struct VhostUserMemoryRegion {
112     uint64_t guest_phys_addr;
113     uint64_t memory_size;
114     uint64_t userspace_addr;
115     uint64_t mmap_offset;
116 } VhostUserMemoryRegion;
117 
118 typedef struct VhostUserMemory {
119     uint32_t nregions;
120     uint32_t padding;
121     VhostUserMemoryRegion regions[VHOST_MEMORY_MAX_NREGIONS];
122 } VhostUserMemory;
123 
124 typedef struct VhostUserLog {
125     uint64_t mmap_size;
126     uint64_t mmap_offset;
127 } VhostUserLog;
128 
129 typedef struct VhostUserConfig {
130     uint32_t offset;
131     uint32_t size;
132     uint32_t flags;
133     uint8_t region[VHOST_USER_MAX_CONFIG_SIZE];
134 } VhostUserConfig;
135 
136 #define VHOST_CRYPTO_SYM_HMAC_MAX_KEY_LEN    512
137 #define VHOST_CRYPTO_SYM_CIPHER_MAX_KEY_LEN  64
138 
139 typedef struct VhostUserCryptoSession {
140     /* session id for success, -1 on errors */
141     int64_t session_id;
142     CryptoDevBackendSymSessionInfo session_setup_data;
143     uint8_t key[VHOST_CRYPTO_SYM_CIPHER_MAX_KEY_LEN];
144     uint8_t auth_key[VHOST_CRYPTO_SYM_HMAC_MAX_KEY_LEN];
145 } VhostUserCryptoSession;
146 
147 static VhostUserConfig c __attribute__ ((unused));
148 #define VHOST_USER_CONFIG_HDR_SIZE (sizeof(c.offset) \
149                                    + sizeof(c.size) \
150                                    + sizeof(c.flags))
151 
152 typedef struct VhostUserVringArea {
153     uint64_t u64;
154     uint64_t size;
155     uint64_t offset;
156 } VhostUserVringArea;
157 
158 typedef struct VhostUserInflight {
159     uint64_t mmap_size;
160     uint64_t mmap_offset;
161     uint16_t num_queues;
162     uint16_t queue_size;
163 } VhostUserInflight;
164 
165 typedef struct {
166     VhostUserRequest request;
167 
168 #define VHOST_USER_VERSION_MASK     (0x3)
169 #define VHOST_USER_REPLY_MASK       (0x1<<2)
170 #define VHOST_USER_NEED_REPLY_MASK  (0x1 << 3)
171     uint32_t flags;
172     uint32_t size; /* the following payload size */
173 } QEMU_PACKED VhostUserHeader;
174 
175 typedef union {
176 #define VHOST_USER_VRING_IDX_MASK   (0xff)
177 #define VHOST_USER_VRING_NOFD_MASK  (0x1<<8)
178         uint64_t u64;
179         struct vhost_vring_state state;
180         struct vhost_vring_addr addr;
181         VhostUserMemory memory;
182         VhostUserLog log;
183         struct vhost_iotlb_msg iotlb;
184         VhostUserConfig config;
185         VhostUserCryptoSession session;
186         VhostUserVringArea area;
187         VhostUserInflight inflight;
188 } VhostUserPayload;
189 
190 typedef struct VhostUserMsg {
191     VhostUserHeader hdr;
192     VhostUserPayload payload;
193 } QEMU_PACKED VhostUserMsg;
194 
195 static VhostUserMsg m __attribute__ ((unused));
196 #define VHOST_USER_HDR_SIZE (sizeof(VhostUserHeader))
197 
198 #define VHOST_USER_PAYLOAD_SIZE (sizeof(VhostUserPayload))
199 
200 /* The version of the protocol we support */
201 #define VHOST_USER_VERSION    (0x1)
202 
203 struct vhost_user {
204     struct vhost_dev *dev;
205     /* Shared between vhost devs of the same virtio device */
206     VhostUserState *user;
207     int slave_fd;
208     NotifierWithReturn postcopy_notifier;
209     struct PostCopyFD  postcopy_fd;
210     uint64_t           postcopy_client_bases[VHOST_MEMORY_MAX_NREGIONS];
211     /* Length of the region_rb and region_rb_offset arrays */
212     size_t             region_rb_len;
213     /* RAMBlock associated with a given region */
214     RAMBlock         **region_rb;
215     /* The offset from the start of the RAMBlock to the start of the
216      * vhost region.
217      */
218     ram_addr_t        *region_rb_offset;
219 
220     /* True once we've entered postcopy_listen */
221     bool               postcopy_listen;
222 };
223 
224 static bool ioeventfd_enabled(void)
225 {
226     return !kvm_enabled() || kvm_eventfds_enabled();
227 }
228 
229 static int vhost_user_read_header(struct vhost_dev *dev, VhostUserMsg *msg)
230 {
231     struct vhost_user *u = dev->opaque;
232     CharBackend *chr = u->user->chr;
233     uint8_t *p = (uint8_t *) msg;
234     int r, size = VHOST_USER_HDR_SIZE;
235 
236     r = qemu_chr_fe_read_all(chr, p, size);
237     if (r != size) {
238         error_report("Failed to read msg header. Read %d instead of %d."
239                      " Original request %d.", r, size, msg->hdr.request);
240         return -1;
241     }
242 
243     /* validate received flags */
244     if (msg->hdr.flags != (VHOST_USER_REPLY_MASK | VHOST_USER_VERSION)) {
245         error_report("Failed to read msg header."
246                 " Flags 0x%x instead of 0x%x.", msg->hdr.flags,
247                 VHOST_USER_REPLY_MASK | VHOST_USER_VERSION);
248         return -1;
249     }
250 
251     return 0;
252 }
253 
254 static int vhost_user_read(struct vhost_dev *dev, VhostUserMsg *msg)
255 {
256     struct vhost_user *u = dev->opaque;
257     CharBackend *chr = u->user->chr;
258     uint8_t *p = (uint8_t *) msg;
259     int r, size;
260 
261     if (vhost_user_read_header(dev, msg) < 0) {
262         return -1;
263     }
264 
265     /* validate message size is sane */
266     if (msg->hdr.size > VHOST_USER_PAYLOAD_SIZE) {
267         error_report("Failed to read msg header."
268                 " Size %d exceeds the maximum %zu.", msg->hdr.size,
269                 VHOST_USER_PAYLOAD_SIZE);
270         return -1;
271     }
272 
273     if (msg->hdr.size) {
274         p += VHOST_USER_HDR_SIZE;
275         size = msg->hdr.size;
276         r = qemu_chr_fe_read_all(chr, p, size);
277         if (r != size) {
278             error_report("Failed to read msg payload."
279                          " Read %d instead of %d.", r, msg->hdr.size);
280             return -1;
281         }
282     }
283 
284     return 0;
285 }
286 
287 static int process_message_reply(struct vhost_dev *dev,
288                                  const VhostUserMsg *msg)
289 {
290     VhostUserMsg msg_reply;
291 
292     if ((msg->hdr.flags & VHOST_USER_NEED_REPLY_MASK) == 0) {
293         return 0;
294     }
295 
296     if (vhost_user_read(dev, &msg_reply) < 0) {
297         return -1;
298     }
299 
300     if (msg_reply.hdr.request != msg->hdr.request) {
301         error_report("Received unexpected msg type."
302                      "Expected %d received %d",
303                      msg->hdr.request, msg_reply.hdr.request);
304         return -1;
305     }
306 
307     return msg_reply.payload.u64 ? -1 : 0;
308 }
309 
310 static bool vhost_user_one_time_request(VhostUserRequest request)
311 {
312     switch (request) {
313     case VHOST_USER_SET_OWNER:
314     case VHOST_USER_RESET_OWNER:
315     case VHOST_USER_SET_MEM_TABLE:
316     case VHOST_USER_GET_QUEUE_NUM:
317     case VHOST_USER_NET_SET_MTU:
318         return true;
319     default:
320         return false;
321     }
322 }
323 
324 /* most non-init callers ignore the error */
325 static int vhost_user_write(struct vhost_dev *dev, VhostUserMsg *msg,
326                             int *fds, int fd_num)
327 {
328     struct vhost_user *u = dev->opaque;
329     CharBackend *chr = u->user->chr;
330     int ret, size = VHOST_USER_HDR_SIZE + msg->hdr.size;
331 
332     /*
333      * For non-vring specific requests, like VHOST_USER_SET_MEM_TABLE,
334      * we just need send it once in the first time. For later such
335      * request, we just ignore it.
336      */
337     if (vhost_user_one_time_request(msg->hdr.request) && dev->vq_index != 0) {
338         msg->hdr.flags &= ~VHOST_USER_NEED_REPLY_MASK;
339         return 0;
340     }
341 
342     if (qemu_chr_fe_set_msgfds(chr, fds, fd_num) < 0) {
343         error_report("Failed to set msg fds.");
344         return -1;
345     }
346 
347     ret = qemu_chr_fe_write_all(chr, (const uint8_t *) msg, size);
348     if (ret != size) {
349         error_report("Failed to write msg."
350                      " Wrote %d instead of %d.", ret, size);
351         return -1;
352     }
353 
354     return 0;
355 }
356 
357 int vhost_user_gpu_set_socket(struct vhost_dev *dev, int fd)
358 {
359     VhostUserMsg msg = {
360         .hdr.request = VHOST_USER_GPU_SET_SOCKET,
361         .hdr.flags = VHOST_USER_VERSION,
362     };
363 
364     return vhost_user_write(dev, &msg, &fd, 1);
365 }
366 
367 static int vhost_user_set_log_base(struct vhost_dev *dev, uint64_t base,
368                                    struct vhost_log *log)
369 {
370     int fds[VHOST_MEMORY_MAX_NREGIONS];
371     size_t fd_num = 0;
372     bool shmfd = virtio_has_feature(dev->protocol_features,
373                                     VHOST_USER_PROTOCOL_F_LOG_SHMFD);
374     VhostUserMsg msg = {
375         .hdr.request = VHOST_USER_SET_LOG_BASE,
376         .hdr.flags = VHOST_USER_VERSION,
377         .payload.log.mmap_size = log->size * sizeof(*(log->log)),
378         .payload.log.mmap_offset = 0,
379         .hdr.size = sizeof(msg.payload.log),
380     };
381 
382     if (shmfd && log->fd != -1) {
383         fds[fd_num++] = log->fd;
384     }
385 
386     if (vhost_user_write(dev, &msg, fds, fd_num) < 0) {
387         return -1;
388     }
389 
390     if (shmfd) {
391         msg.hdr.size = 0;
392         if (vhost_user_read(dev, &msg) < 0) {
393             return -1;
394         }
395 
396         if (msg.hdr.request != VHOST_USER_SET_LOG_BASE) {
397             error_report("Received unexpected msg type. "
398                          "Expected %d received %d",
399                          VHOST_USER_SET_LOG_BASE, msg.hdr.request);
400             return -1;
401         }
402     }
403 
404     return 0;
405 }
406 
407 static int vhost_user_set_mem_table_postcopy(struct vhost_dev *dev,
408                                              struct vhost_memory *mem)
409 {
410     struct vhost_user *u = dev->opaque;
411     int fds[VHOST_MEMORY_MAX_NREGIONS];
412     int i, fd;
413     size_t fd_num = 0;
414     VhostUserMsg msg_reply;
415     int region_i, msg_i;
416 
417     VhostUserMsg msg = {
418         .hdr.request = VHOST_USER_SET_MEM_TABLE,
419         .hdr.flags = VHOST_USER_VERSION,
420     };
421 
422     if (u->region_rb_len < dev->mem->nregions) {
423         u->region_rb = g_renew(RAMBlock*, u->region_rb, dev->mem->nregions);
424         u->region_rb_offset = g_renew(ram_addr_t, u->region_rb_offset,
425                                       dev->mem->nregions);
426         memset(&(u->region_rb[u->region_rb_len]), '\0',
427                sizeof(RAMBlock *) * (dev->mem->nregions - u->region_rb_len));
428         memset(&(u->region_rb_offset[u->region_rb_len]), '\0',
429                sizeof(ram_addr_t) * (dev->mem->nregions - u->region_rb_len));
430         u->region_rb_len = dev->mem->nregions;
431     }
432 
433     for (i = 0; i < dev->mem->nregions; ++i) {
434         struct vhost_memory_region *reg = dev->mem->regions + i;
435         ram_addr_t offset;
436         MemoryRegion *mr;
437 
438         assert((uintptr_t)reg->userspace_addr == reg->userspace_addr);
439         mr = memory_region_from_host((void *)(uintptr_t)reg->userspace_addr,
440                                      &offset);
441         fd = memory_region_get_fd(mr);
442         if (fd > 0) {
443             trace_vhost_user_set_mem_table_withfd(fd_num, mr->name,
444                                                   reg->memory_size,
445                                                   reg->guest_phys_addr,
446                                                   reg->userspace_addr, offset);
447             u->region_rb_offset[i] = offset;
448             u->region_rb[i] = mr->ram_block;
449             msg.payload.memory.regions[fd_num].userspace_addr =
450                 reg->userspace_addr;
451             msg.payload.memory.regions[fd_num].memory_size  = reg->memory_size;
452             msg.payload.memory.regions[fd_num].guest_phys_addr =
453                 reg->guest_phys_addr;
454             msg.payload.memory.regions[fd_num].mmap_offset = offset;
455             assert(fd_num < VHOST_MEMORY_MAX_NREGIONS);
456             fds[fd_num++] = fd;
457         } else {
458             u->region_rb_offset[i] = 0;
459             u->region_rb[i] = NULL;
460         }
461     }
462 
463     msg.payload.memory.nregions = fd_num;
464 
465     if (!fd_num) {
466         error_report("Failed initializing vhost-user memory map, "
467                      "consider using -object memory-backend-file share=on");
468         return -1;
469     }
470 
471     msg.hdr.size = sizeof(msg.payload.memory.nregions);
472     msg.hdr.size += sizeof(msg.payload.memory.padding);
473     msg.hdr.size += fd_num * sizeof(VhostUserMemoryRegion);
474 
475     if (vhost_user_write(dev, &msg, fds, fd_num) < 0) {
476         return -1;
477     }
478 
479     if (vhost_user_read(dev, &msg_reply) < 0) {
480         return -1;
481     }
482 
483     if (msg_reply.hdr.request != VHOST_USER_SET_MEM_TABLE) {
484         error_report("%s: Received unexpected msg type."
485                      "Expected %d received %d", __func__,
486                      VHOST_USER_SET_MEM_TABLE, msg_reply.hdr.request);
487         return -1;
488     }
489     /* We're using the same structure, just reusing one of the
490      * fields, so it should be the same size.
491      */
492     if (msg_reply.hdr.size != msg.hdr.size) {
493         error_report("%s: Unexpected size for postcopy reply "
494                      "%d vs %d", __func__, msg_reply.hdr.size, msg.hdr.size);
495         return -1;
496     }
497 
498     memset(u->postcopy_client_bases, 0,
499            sizeof(uint64_t) * VHOST_MEMORY_MAX_NREGIONS);
500 
501     /* They're in the same order as the regions that were sent
502      * but some of the regions were skipped (above) if they
503      * didn't have fd's
504     */
505     for (msg_i = 0, region_i = 0;
506          region_i < dev->mem->nregions;
507         region_i++) {
508         if (msg_i < fd_num &&
509             msg_reply.payload.memory.regions[msg_i].guest_phys_addr ==
510             dev->mem->regions[region_i].guest_phys_addr) {
511             u->postcopy_client_bases[region_i] =
512                 msg_reply.payload.memory.regions[msg_i].userspace_addr;
513             trace_vhost_user_set_mem_table_postcopy(
514                 msg_reply.payload.memory.regions[msg_i].userspace_addr,
515                 msg.payload.memory.regions[msg_i].userspace_addr,
516                 msg_i, region_i);
517             msg_i++;
518         }
519     }
520     if (msg_i != fd_num) {
521         error_report("%s: postcopy reply not fully consumed "
522                      "%d vs %zd",
523                      __func__, msg_i, fd_num);
524         return -1;
525     }
526     /* Now we've registered this with the postcopy code, we ack to the client,
527      * because now we're in the position to be able to deal with any faults
528      * it generates.
529      */
530     /* TODO: Use this for failure cases as well with a bad value */
531     msg.hdr.size = sizeof(msg.payload.u64);
532     msg.payload.u64 = 0; /* OK */
533     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
534         return -1;
535     }
536 
537     return 0;
538 }
539 
540 static int vhost_user_set_mem_table(struct vhost_dev *dev,
541                                     struct vhost_memory *mem)
542 {
543     struct vhost_user *u = dev->opaque;
544     int fds[VHOST_MEMORY_MAX_NREGIONS];
545     int i, fd;
546     size_t fd_num = 0;
547     bool do_postcopy = u->postcopy_listen && u->postcopy_fd.handler;
548     bool reply_supported = virtio_has_feature(dev->protocol_features,
549                                               VHOST_USER_PROTOCOL_F_REPLY_ACK);
550 
551     if (do_postcopy) {
552         /* Postcopy has enough differences that it's best done in it's own
553          * version
554          */
555         return vhost_user_set_mem_table_postcopy(dev, mem);
556     }
557 
558     VhostUserMsg msg = {
559         .hdr.request = VHOST_USER_SET_MEM_TABLE,
560         .hdr.flags = VHOST_USER_VERSION,
561     };
562 
563     if (reply_supported) {
564         msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
565     }
566 
567     for (i = 0; i < dev->mem->nregions; ++i) {
568         struct vhost_memory_region *reg = dev->mem->regions + i;
569         ram_addr_t offset;
570         MemoryRegion *mr;
571 
572         assert((uintptr_t)reg->userspace_addr == reg->userspace_addr);
573         mr = memory_region_from_host((void *)(uintptr_t)reg->userspace_addr,
574                                      &offset);
575         fd = memory_region_get_fd(mr);
576         if (fd > 0) {
577             if (fd_num == VHOST_MEMORY_MAX_NREGIONS) {
578                 error_report("Failed preparing vhost-user memory table msg");
579                 return -1;
580             }
581             msg.payload.memory.regions[fd_num].userspace_addr =
582                 reg->userspace_addr;
583             msg.payload.memory.regions[fd_num].memory_size  = reg->memory_size;
584             msg.payload.memory.regions[fd_num].guest_phys_addr =
585                 reg->guest_phys_addr;
586             msg.payload.memory.regions[fd_num].mmap_offset = offset;
587             fds[fd_num++] = fd;
588         }
589     }
590 
591     msg.payload.memory.nregions = fd_num;
592 
593     if (!fd_num) {
594         error_report("Failed initializing vhost-user memory map, "
595                      "consider using -object memory-backend-file share=on");
596         return -1;
597     }
598 
599     msg.hdr.size = sizeof(msg.payload.memory.nregions);
600     msg.hdr.size += sizeof(msg.payload.memory.padding);
601     msg.hdr.size += fd_num * sizeof(VhostUserMemoryRegion);
602 
603     if (vhost_user_write(dev, &msg, fds, fd_num) < 0) {
604         return -1;
605     }
606 
607     if (reply_supported) {
608         return process_message_reply(dev, &msg);
609     }
610 
611     return 0;
612 }
613 
614 static int vhost_user_set_vring_addr(struct vhost_dev *dev,
615                                      struct vhost_vring_addr *addr)
616 {
617     VhostUserMsg msg = {
618         .hdr.request = VHOST_USER_SET_VRING_ADDR,
619         .hdr.flags = VHOST_USER_VERSION,
620         .payload.addr = *addr,
621         .hdr.size = sizeof(msg.payload.addr),
622     };
623 
624     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
625         return -1;
626     }
627 
628     return 0;
629 }
630 
631 static int vhost_user_set_vring_endian(struct vhost_dev *dev,
632                                        struct vhost_vring_state *ring)
633 {
634     bool cross_endian = virtio_has_feature(dev->protocol_features,
635                                            VHOST_USER_PROTOCOL_F_CROSS_ENDIAN);
636     VhostUserMsg msg = {
637         .hdr.request = VHOST_USER_SET_VRING_ENDIAN,
638         .hdr.flags = VHOST_USER_VERSION,
639         .payload.state = *ring,
640         .hdr.size = sizeof(msg.payload.state),
641     };
642 
643     if (!cross_endian) {
644         error_report("vhost-user trying to send unhandled ioctl");
645         return -1;
646     }
647 
648     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
649         return -1;
650     }
651 
652     return 0;
653 }
654 
655 static int vhost_set_vring(struct vhost_dev *dev,
656                            unsigned long int request,
657                            struct vhost_vring_state *ring)
658 {
659     VhostUserMsg msg = {
660         .hdr.request = request,
661         .hdr.flags = VHOST_USER_VERSION,
662         .payload.state = *ring,
663         .hdr.size = sizeof(msg.payload.state),
664     };
665 
666     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
667         return -1;
668     }
669 
670     return 0;
671 }
672 
673 static int vhost_user_set_vring_num(struct vhost_dev *dev,
674                                     struct vhost_vring_state *ring)
675 {
676     return vhost_set_vring(dev, VHOST_USER_SET_VRING_NUM, ring);
677 }
678 
679 static void vhost_user_host_notifier_restore(struct vhost_dev *dev,
680                                              int queue_idx)
681 {
682     struct vhost_user *u = dev->opaque;
683     VhostUserHostNotifier *n = &u->user->notifier[queue_idx];
684     VirtIODevice *vdev = dev->vdev;
685 
686     if (n->addr && !n->set) {
687         virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, true);
688         n->set = true;
689     }
690 }
691 
692 static void vhost_user_host_notifier_remove(struct vhost_dev *dev,
693                                             int queue_idx)
694 {
695     struct vhost_user *u = dev->opaque;
696     VhostUserHostNotifier *n = &u->user->notifier[queue_idx];
697     VirtIODevice *vdev = dev->vdev;
698 
699     if (n->addr && n->set) {
700         virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, false);
701         n->set = false;
702     }
703 }
704 
705 static int vhost_user_set_vring_base(struct vhost_dev *dev,
706                                      struct vhost_vring_state *ring)
707 {
708     vhost_user_host_notifier_restore(dev, ring->index);
709 
710     return vhost_set_vring(dev, VHOST_USER_SET_VRING_BASE, ring);
711 }
712 
713 static int vhost_user_set_vring_enable(struct vhost_dev *dev, int enable)
714 {
715     int i;
716 
717     if (!virtio_has_feature(dev->features, VHOST_USER_F_PROTOCOL_FEATURES)) {
718         return -1;
719     }
720 
721     for (i = 0; i < dev->nvqs; ++i) {
722         struct vhost_vring_state state = {
723             .index = dev->vq_index + i,
724             .num   = enable,
725         };
726 
727         vhost_set_vring(dev, VHOST_USER_SET_VRING_ENABLE, &state);
728     }
729 
730     return 0;
731 }
732 
733 static int vhost_user_get_vring_base(struct vhost_dev *dev,
734                                      struct vhost_vring_state *ring)
735 {
736     VhostUserMsg msg = {
737         .hdr.request = VHOST_USER_GET_VRING_BASE,
738         .hdr.flags = VHOST_USER_VERSION,
739         .payload.state = *ring,
740         .hdr.size = sizeof(msg.payload.state),
741     };
742 
743     vhost_user_host_notifier_remove(dev, ring->index);
744 
745     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
746         return -1;
747     }
748 
749     if (vhost_user_read(dev, &msg) < 0) {
750         return -1;
751     }
752 
753     if (msg.hdr.request != VHOST_USER_GET_VRING_BASE) {
754         error_report("Received unexpected msg type. Expected %d received %d",
755                      VHOST_USER_GET_VRING_BASE, msg.hdr.request);
756         return -1;
757     }
758 
759     if (msg.hdr.size != sizeof(msg.payload.state)) {
760         error_report("Received bad msg size.");
761         return -1;
762     }
763 
764     *ring = msg.payload.state;
765 
766     return 0;
767 }
768 
769 static int vhost_set_vring_file(struct vhost_dev *dev,
770                                 VhostUserRequest request,
771                                 struct vhost_vring_file *file)
772 {
773     int fds[VHOST_MEMORY_MAX_NREGIONS];
774     size_t fd_num = 0;
775     VhostUserMsg msg = {
776         .hdr.request = request,
777         .hdr.flags = VHOST_USER_VERSION,
778         .payload.u64 = file->index & VHOST_USER_VRING_IDX_MASK,
779         .hdr.size = sizeof(msg.payload.u64),
780     };
781 
782     if (ioeventfd_enabled() && file->fd > 0) {
783         fds[fd_num++] = file->fd;
784     } else {
785         msg.payload.u64 |= VHOST_USER_VRING_NOFD_MASK;
786     }
787 
788     if (vhost_user_write(dev, &msg, fds, fd_num) < 0) {
789         return -1;
790     }
791 
792     return 0;
793 }
794 
795 static int vhost_user_set_vring_kick(struct vhost_dev *dev,
796                                      struct vhost_vring_file *file)
797 {
798     return vhost_set_vring_file(dev, VHOST_USER_SET_VRING_KICK, file);
799 }
800 
801 static int vhost_user_set_vring_call(struct vhost_dev *dev,
802                                      struct vhost_vring_file *file)
803 {
804     return vhost_set_vring_file(dev, VHOST_USER_SET_VRING_CALL, file);
805 }
806 
807 static int vhost_user_set_u64(struct vhost_dev *dev, int request, uint64_t u64)
808 {
809     VhostUserMsg msg = {
810         .hdr.request = request,
811         .hdr.flags = VHOST_USER_VERSION,
812         .payload.u64 = u64,
813         .hdr.size = sizeof(msg.payload.u64),
814     };
815 
816     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
817         return -1;
818     }
819 
820     return 0;
821 }
822 
823 static int vhost_user_set_features(struct vhost_dev *dev,
824                                    uint64_t features)
825 {
826     return vhost_user_set_u64(dev, VHOST_USER_SET_FEATURES, features);
827 }
828 
829 static int vhost_user_set_protocol_features(struct vhost_dev *dev,
830                                             uint64_t features)
831 {
832     return vhost_user_set_u64(dev, VHOST_USER_SET_PROTOCOL_FEATURES, features);
833 }
834 
835 static int vhost_user_get_u64(struct vhost_dev *dev, int request, uint64_t *u64)
836 {
837     VhostUserMsg msg = {
838         .hdr.request = request,
839         .hdr.flags = VHOST_USER_VERSION,
840     };
841 
842     if (vhost_user_one_time_request(request) && dev->vq_index != 0) {
843         return 0;
844     }
845 
846     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
847         return -1;
848     }
849 
850     if (vhost_user_read(dev, &msg) < 0) {
851         return -1;
852     }
853 
854     if (msg.hdr.request != request) {
855         error_report("Received unexpected msg type. Expected %d received %d",
856                      request, msg.hdr.request);
857         return -1;
858     }
859 
860     if (msg.hdr.size != sizeof(msg.payload.u64)) {
861         error_report("Received bad msg size.");
862         return -1;
863     }
864 
865     *u64 = msg.payload.u64;
866 
867     return 0;
868 }
869 
870 static int vhost_user_get_features(struct vhost_dev *dev, uint64_t *features)
871 {
872     return vhost_user_get_u64(dev, VHOST_USER_GET_FEATURES, features);
873 }
874 
875 static int vhost_user_set_owner(struct vhost_dev *dev)
876 {
877     VhostUserMsg msg = {
878         .hdr.request = VHOST_USER_SET_OWNER,
879         .hdr.flags = VHOST_USER_VERSION,
880     };
881 
882     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
883         return -1;
884     }
885 
886     return 0;
887 }
888 
889 static int vhost_user_reset_device(struct vhost_dev *dev)
890 {
891     VhostUserMsg msg = {
892         .hdr.request = VHOST_USER_RESET_OWNER,
893         .hdr.flags = VHOST_USER_VERSION,
894     };
895 
896     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
897         return -1;
898     }
899 
900     return 0;
901 }
902 
903 static int vhost_user_slave_handle_config_change(struct vhost_dev *dev)
904 {
905     int ret = -1;
906 
907     if (!dev->config_ops) {
908         return -1;
909     }
910 
911     if (dev->config_ops->vhost_dev_config_notifier) {
912         ret = dev->config_ops->vhost_dev_config_notifier(dev);
913     }
914 
915     return ret;
916 }
917 
918 static int vhost_user_slave_handle_vring_host_notifier(struct vhost_dev *dev,
919                                                        VhostUserVringArea *area,
920                                                        int fd)
921 {
922     int queue_idx = area->u64 & VHOST_USER_VRING_IDX_MASK;
923     size_t page_size = qemu_real_host_page_size;
924     struct vhost_user *u = dev->opaque;
925     VhostUserState *user = u->user;
926     VirtIODevice *vdev = dev->vdev;
927     VhostUserHostNotifier *n;
928     void *addr;
929     char *name;
930 
931     if (!virtio_has_feature(dev->protocol_features,
932                             VHOST_USER_PROTOCOL_F_HOST_NOTIFIER) ||
933         vdev == NULL || queue_idx >= virtio_get_num_queues(vdev)) {
934         return -1;
935     }
936 
937     n = &user->notifier[queue_idx];
938 
939     if (n->addr) {
940         virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, false);
941         object_unparent(OBJECT(&n->mr));
942         munmap(n->addr, page_size);
943         n->addr = NULL;
944     }
945 
946     if (area->u64 & VHOST_USER_VRING_NOFD_MASK) {
947         return 0;
948     }
949 
950     /* Sanity check. */
951     if (area->size != page_size) {
952         return -1;
953     }
954 
955     addr = mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_SHARED,
956                 fd, area->offset);
957     if (addr == MAP_FAILED) {
958         return -1;
959     }
960 
961     name = g_strdup_printf("vhost-user/host-notifier@%p mmaps[%d]",
962                            user, queue_idx);
963     memory_region_init_ram_device_ptr(&n->mr, OBJECT(vdev), name,
964                                       page_size, addr);
965     g_free(name);
966 
967     if (virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, true)) {
968         munmap(addr, page_size);
969         return -1;
970     }
971 
972     n->addr = addr;
973     n->set = true;
974 
975     return 0;
976 }
977 
978 static void slave_read(void *opaque)
979 {
980     struct vhost_dev *dev = opaque;
981     struct vhost_user *u = dev->opaque;
982     VhostUserHeader hdr = { 0, };
983     VhostUserPayload payload = { 0, };
984     int size, ret = 0;
985     struct iovec iov;
986     struct msghdr msgh;
987     int fd[VHOST_USER_SLAVE_MAX_FDS];
988     char control[CMSG_SPACE(sizeof(fd))];
989     struct cmsghdr *cmsg;
990     int i, fdsize = 0;
991 
992     memset(&msgh, 0, sizeof(msgh));
993     msgh.msg_iov = &iov;
994     msgh.msg_iovlen = 1;
995     msgh.msg_control = control;
996     msgh.msg_controllen = sizeof(control);
997 
998     memset(fd, -1, sizeof(fd));
999 
1000     /* Read header */
1001     iov.iov_base = &hdr;
1002     iov.iov_len = VHOST_USER_HDR_SIZE;
1003 
1004     do {
1005         size = recvmsg(u->slave_fd, &msgh, 0);
1006     } while (size < 0 && (errno == EINTR || errno == EAGAIN));
1007 
1008     if (size != VHOST_USER_HDR_SIZE) {
1009         error_report("Failed to read from slave.");
1010         goto err;
1011     }
1012 
1013     if (msgh.msg_flags & MSG_CTRUNC) {
1014         error_report("Truncated message.");
1015         goto err;
1016     }
1017 
1018     for (cmsg = CMSG_FIRSTHDR(&msgh); cmsg != NULL;
1019          cmsg = CMSG_NXTHDR(&msgh, cmsg)) {
1020             if (cmsg->cmsg_level == SOL_SOCKET &&
1021                 cmsg->cmsg_type == SCM_RIGHTS) {
1022                     fdsize = cmsg->cmsg_len - CMSG_LEN(0);
1023                     memcpy(fd, CMSG_DATA(cmsg), fdsize);
1024                     break;
1025             }
1026     }
1027 
1028     if (hdr.size > VHOST_USER_PAYLOAD_SIZE) {
1029         error_report("Failed to read msg header."
1030                 " Size %d exceeds the maximum %zu.", hdr.size,
1031                 VHOST_USER_PAYLOAD_SIZE);
1032         goto err;
1033     }
1034 
1035     /* Read payload */
1036     do {
1037         size = read(u->slave_fd, &payload, hdr.size);
1038     } while (size < 0 && (errno == EINTR || errno == EAGAIN));
1039 
1040     if (size != hdr.size) {
1041         error_report("Failed to read payload from slave.");
1042         goto err;
1043     }
1044 
1045     switch (hdr.request) {
1046     case VHOST_USER_SLAVE_IOTLB_MSG:
1047         ret = vhost_backend_handle_iotlb_msg(dev, &payload.iotlb);
1048         break;
1049     case VHOST_USER_SLAVE_CONFIG_CHANGE_MSG :
1050         ret = vhost_user_slave_handle_config_change(dev);
1051         break;
1052     case VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG:
1053         ret = vhost_user_slave_handle_vring_host_notifier(dev, &payload.area,
1054                                                           fd[0]);
1055         break;
1056     default:
1057         error_report("Received unexpected msg type.");
1058         ret = -EINVAL;
1059     }
1060 
1061     /* Close the remaining file descriptors. */
1062     for (i = 0; i < fdsize; i++) {
1063         if (fd[i] != -1) {
1064             close(fd[i]);
1065         }
1066     }
1067 
1068     /*
1069      * REPLY_ACK feature handling. Other reply types has to be managed
1070      * directly in their request handlers.
1071      */
1072     if (hdr.flags & VHOST_USER_NEED_REPLY_MASK) {
1073         struct iovec iovec[2];
1074 
1075 
1076         hdr.flags &= ~VHOST_USER_NEED_REPLY_MASK;
1077         hdr.flags |= VHOST_USER_REPLY_MASK;
1078 
1079         payload.u64 = !!ret;
1080         hdr.size = sizeof(payload.u64);
1081 
1082         iovec[0].iov_base = &hdr;
1083         iovec[0].iov_len = VHOST_USER_HDR_SIZE;
1084         iovec[1].iov_base = &payload;
1085         iovec[1].iov_len = hdr.size;
1086 
1087         do {
1088             size = writev(u->slave_fd, iovec, ARRAY_SIZE(iovec));
1089         } while (size < 0 && (errno == EINTR || errno == EAGAIN));
1090 
1091         if (size != VHOST_USER_HDR_SIZE + hdr.size) {
1092             error_report("Failed to send msg reply to slave.");
1093             goto err;
1094         }
1095     }
1096 
1097     return;
1098 
1099 err:
1100     qemu_set_fd_handler(u->slave_fd, NULL, NULL, NULL);
1101     close(u->slave_fd);
1102     u->slave_fd = -1;
1103     for (i = 0; i < fdsize; i++) {
1104         if (fd[i] != -1) {
1105             close(fd[i]);
1106         }
1107     }
1108     return;
1109 }
1110 
1111 static int vhost_setup_slave_channel(struct vhost_dev *dev)
1112 {
1113     VhostUserMsg msg = {
1114         .hdr.request = VHOST_USER_SET_SLAVE_REQ_FD,
1115         .hdr.flags = VHOST_USER_VERSION,
1116     };
1117     struct vhost_user *u = dev->opaque;
1118     int sv[2], ret = 0;
1119     bool reply_supported = virtio_has_feature(dev->protocol_features,
1120                                               VHOST_USER_PROTOCOL_F_REPLY_ACK);
1121 
1122     if (!virtio_has_feature(dev->protocol_features,
1123                             VHOST_USER_PROTOCOL_F_SLAVE_REQ)) {
1124         return 0;
1125     }
1126 
1127     if (socketpair(PF_UNIX, SOCK_STREAM, 0, sv) == -1) {
1128         error_report("socketpair() failed");
1129         return -1;
1130     }
1131 
1132     u->slave_fd = sv[0];
1133     qemu_set_fd_handler(u->slave_fd, slave_read, NULL, dev);
1134 
1135     if (reply_supported) {
1136         msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
1137     }
1138 
1139     ret = vhost_user_write(dev, &msg, &sv[1], 1);
1140     if (ret) {
1141         goto out;
1142     }
1143 
1144     if (reply_supported) {
1145         ret = process_message_reply(dev, &msg);
1146     }
1147 
1148 out:
1149     close(sv[1]);
1150     if (ret) {
1151         qemu_set_fd_handler(u->slave_fd, NULL, NULL, NULL);
1152         close(u->slave_fd);
1153         u->slave_fd = -1;
1154     }
1155 
1156     return ret;
1157 }
1158 
1159 #ifdef CONFIG_LINUX
1160 /*
1161  * Called back from the postcopy fault thread when a fault is received on our
1162  * ufd.
1163  * TODO: This is Linux specific
1164  */
1165 static int vhost_user_postcopy_fault_handler(struct PostCopyFD *pcfd,
1166                                              void *ufd)
1167 {
1168     struct vhost_dev *dev = pcfd->data;
1169     struct vhost_user *u = dev->opaque;
1170     struct uffd_msg *msg = ufd;
1171     uint64_t faultaddr = msg->arg.pagefault.address;
1172     RAMBlock *rb = NULL;
1173     uint64_t rb_offset;
1174     int i;
1175 
1176     trace_vhost_user_postcopy_fault_handler(pcfd->idstr, faultaddr,
1177                                             dev->mem->nregions);
1178     for (i = 0; i < MIN(dev->mem->nregions, u->region_rb_len); i++) {
1179         trace_vhost_user_postcopy_fault_handler_loop(i,
1180                 u->postcopy_client_bases[i], dev->mem->regions[i].memory_size);
1181         if (faultaddr >= u->postcopy_client_bases[i]) {
1182             /* Ofset of the fault address in the vhost region */
1183             uint64_t region_offset = faultaddr - u->postcopy_client_bases[i];
1184             if (region_offset < dev->mem->regions[i].memory_size) {
1185                 rb_offset = region_offset + u->region_rb_offset[i];
1186                 trace_vhost_user_postcopy_fault_handler_found(i,
1187                         region_offset, rb_offset);
1188                 rb = u->region_rb[i];
1189                 return postcopy_request_shared_page(pcfd, rb, faultaddr,
1190                                                     rb_offset);
1191             }
1192         }
1193     }
1194     error_report("%s: Failed to find region for fault %" PRIx64,
1195                  __func__, faultaddr);
1196     return -1;
1197 }
1198 
1199 static int vhost_user_postcopy_waker(struct PostCopyFD *pcfd, RAMBlock *rb,
1200                                      uint64_t offset)
1201 {
1202     struct vhost_dev *dev = pcfd->data;
1203     struct vhost_user *u = dev->opaque;
1204     int i;
1205 
1206     trace_vhost_user_postcopy_waker(qemu_ram_get_idstr(rb), offset);
1207 
1208     if (!u) {
1209         return 0;
1210     }
1211     /* Translate the offset into an address in the clients address space */
1212     for (i = 0; i < MIN(dev->mem->nregions, u->region_rb_len); i++) {
1213         if (u->region_rb[i] == rb &&
1214             offset >= u->region_rb_offset[i] &&
1215             offset < (u->region_rb_offset[i] +
1216                       dev->mem->regions[i].memory_size)) {
1217             uint64_t client_addr = (offset - u->region_rb_offset[i]) +
1218                                    u->postcopy_client_bases[i];
1219             trace_vhost_user_postcopy_waker_found(client_addr);
1220             return postcopy_wake_shared(pcfd, client_addr, rb);
1221         }
1222     }
1223 
1224     trace_vhost_user_postcopy_waker_nomatch(qemu_ram_get_idstr(rb), offset);
1225     return 0;
1226 }
1227 #endif
1228 
1229 /*
1230  * Called at the start of an inbound postcopy on reception of the
1231  * 'advise' command.
1232  */
1233 static int vhost_user_postcopy_advise(struct vhost_dev *dev, Error **errp)
1234 {
1235 #ifdef CONFIG_LINUX
1236     struct vhost_user *u = dev->opaque;
1237     CharBackend *chr = u->user->chr;
1238     int ufd;
1239     VhostUserMsg msg = {
1240         .hdr.request = VHOST_USER_POSTCOPY_ADVISE,
1241         .hdr.flags = VHOST_USER_VERSION,
1242     };
1243 
1244     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
1245         error_setg(errp, "Failed to send postcopy_advise to vhost");
1246         return -1;
1247     }
1248 
1249     if (vhost_user_read(dev, &msg) < 0) {
1250         error_setg(errp, "Failed to get postcopy_advise reply from vhost");
1251         return -1;
1252     }
1253 
1254     if (msg.hdr.request != VHOST_USER_POSTCOPY_ADVISE) {
1255         error_setg(errp, "Unexpected msg type. Expected %d received %d",
1256                      VHOST_USER_POSTCOPY_ADVISE, msg.hdr.request);
1257         return -1;
1258     }
1259 
1260     if (msg.hdr.size) {
1261         error_setg(errp, "Received bad msg size.");
1262         return -1;
1263     }
1264     ufd = qemu_chr_fe_get_msgfd(chr);
1265     if (ufd < 0) {
1266         error_setg(errp, "%s: Failed to get ufd", __func__);
1267         return -1;
1268     }
1269     qemu_set_nonblock(ufd);
1270 
1271     /* register ufd with userfault thread */
1272     u->postcopy_fd.fd = ufd;
1273     u->postcopy_fd.data = dev;
1274     u->postcopy_fd.handler = vhost_user_postcopy_fault_handler;
1275     u->postcopy_fd.waker = vhost_user_postcopy_waker;
1276     u->postcopy_fd.idstr = "vhost-user"; /* Need to find unique name */
1277     postcopy_register_shared_ufd(&u->postcopy_fd);
1278     return 0;
1279 #else
1280     error_setg(errp, "Postcopy not supported on non-Linux systems");
1281     return -1;
1282 #endif
1283 }
1284 
1285 /*
1286  * Called at the switch to postcopy on reception of the 'listen' command.
1287  */
1288 static int vhost_user_postcopy_listen(struct vhost_dev *dev, Error **errp)
1289 {
1290     struct vhost_user *u = dev->opaque;
1291     int ret;
1292     VhostUserMsg msg = {
1293         .hdr.request = VHOST_USER_POSTCOPY_LISTEN,
1294         .hdr.flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK,
1295     };
1296     u->postcopy_listen = true;
1297     trace_vhost_user_postcopy_listen();
1298     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
1299         error_setg(errp, "Failed to send postcopy_listen to vhost");
1300         return -1;
1301     }
1302 
1303     ret = process_message_reply(dev, &msg);
1304     if (ret) {
1305         error_setg(errp, "Failed to receive reply to postcopy_listen");
1306         return ret;
1307     }
1308 
1309     return 0;
1310 }
1311 
1312 /*
1313  * Called at the end of postcopy
1314  */
1315 static int vhost_user_postcopy_end(struct vhost_dev *dev, Error **errp)
1316 {
1317     VhostUserMsg msg = {
1318         .hdr.request = VHOST_USER_POSTCOPY_END,
1319         .hdr.flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK,
1320     };
1321     int ret;
1322     struct vhost_user *u = dev->opaque;
1323 
1324     trace_vhost_user_postcopy_end_entry();
1325     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
1326         error_setg(errp, "Failed to send postcopy_end to vhost");
1327         return -1;
1328     }
1329 
1330     ret = process_message_reply(dev, &msg);
1331     if (ret) {
1332         error_setg(errp, "Failed to receive reply to postcopy_end");
1333         return ret;
1334     }
1335     postcopy_unregister_shared_ufd(&u->postcopy_fd);
1336     close(u->postcopy_fd.fd);
1337     u->postcopy_fd.handler = NULL;
1338 
1339     trace_vhost_user_postcopy_end_exit();
1340 
1341     return 0;
1342 }
1343 
1344 static int vhost_user_postcopy_notifier(NotifierWithReturn *notifier,
1345                                         void *opaque)
1346 {
1347     struct PostcopyNotifyData *pnd = opaque;
1348     struct vhost_user *u = container_of(notifier, struct vhost_user,
1349                                          postcopy_notifier);
1350     struct vhost_dev *dev = u->dev;
1351 
1352     switch (pnd->reason) {
1353     case POSTCOPY_NOTIFY_PROBE:
1354         if (!virtio_has_feature(dev->protocol_features,
1355                                 VHOST_USER_PROTOCOL_F_PAGEFAULT)) {
1356             /* TODO: Get the device name into this error somehow */
1357             error_setg(pnd->errp,
1358                        "vhost-user backend not capable of postcopy");
1359             return -ENOENT;
1360         }
1361         break;
1362 
1363     case POSTCOPY_NOTIFY_INBOUND_ADVISE:
1364         return vhost_user_postcopy_advise(dev, pnd->errp);
1365 
1366     case POSTCOPY_NOTIFY_INBOUND_LISTEN:
1367         return vhost_user_postcopy_listen(dev, pnd->errp);
1368 
1369     case POSTCOPY_NOTIFY_INBOUND_END:
1370         return vhost_user_postcopy_end(dev, pnd->errp);
1371 
1372     default:
1373         /* We ignore notifications we don't know */
1374         break;
1375     }
1376 
1377     return 0;
1378 }
1379 
1380 static int vhost_user_backend_init(struct vhost_dev *dev, void *opaque)
1381 {
1382     uint64_t features, protocol_features;
1383     struct vhost_user *u;
1384     int err;
1385 
1386     assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
1387 
1388     u = g_new0(struct vhost_user, 1);
1389     u->user = opaque;
1390     u->slave_fd = -1;
1391     u->dev = dev;
1392     dev->opaque = u;
1393 
1394     err = vhost_user_get_features(dev, &features);
1395     if (err < 0) {
1396         return err;
1397     }
1398 
1399     if (virtio_has_feature(features, VHOST_USER_F_PROTOCOL_FEATURES)) {
1400         dev->backend_features |= 1ULL << VHOST_USER_F_PROTOCOL_FEATURES;
1401 
1402         err = vhost_user_get_u64(dev, VHOST_USER_GET_PROTOCOL_FEATURES,
1403                                  &protocol_features);
1404         if (err < 0) {
1405             return err;
1406         }
1407 
1408         dev->protocol_features =
1409             protocol_features & VHOST_USER_PROTOCOL_FEATURE_MASK;
1410 
1411         if (!dev->config_ops || !dev->config_ops->vhost_dev_config_notifier) {
1412             /* Don't acknowledge CONFIG feature if device doesn't support it */
1413             dev->protocol_features &= ~(1ULL << VHOST_USER_PROTOCOL_F_CONFIG);
1414         } else if (!(protocol_features &
1415                     (1ULL << VHOST_USER_PROTOCOL_F_CONFIG))) {
1416             error_report("Device expects VHOST_USER_PROTOCOL_F_CONFIG "
1417                     "but backend does not support it.");
1418             return -1;
1419         }
1420 
1421         err = vhost_user_set_protocol_features(dev, dev->protocol_features);
1422         if (err < 0) {
1423             return err;
1424         }
1425 
1426         /* query the max queues we support if backend supports Multiple Queue */
1427         if (dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_MQ)) {
1428             err = vhost_user_get_u64(dev, VHOST_USER_GET_QUEUE_NUM,
1429                                      &dev->max_queues);
1430             if (err < 0) {
1431                 return err;
1432             }
1433         }
1434 
1435         if (virtio_has_feature(features, VIRTIO_F_IOMMU_PLATFORM) &&
1436                 !(virtio_has_feature(dev->protocol_features,
1437                     VHOST_USER_PROTOCOL_F_SLAVE_REQ) &&
1438                  virtio_has_feature(dev->protocol_features,
1439                     VHOST_USER_PROTOCOL_F_REPLY_ACK))) {
1440             error_report("IOMMU support requires reply-ack and "
1441                          "slave-req protocol features.");
1442             return -1;
1443         }
1444     }
1445 
1446     if (dev->migration_blocker == NULL &&
1447         !virtio_has_feature(dev->protocol_features,
1448                             VHOST_USER_PROTOCOL_F_LOG_SHMFD)) {
1449         error_setg(&dev->migration_blocker,
1450                    "Migration disabled: vhost-user backend lacks "
1451                    "VHOST_USER_PROTOCOL_F_LOG_SHMFD feature.");
1452     }
1453 
1454     err = vhost_setup_slave_channel(dev);
1455     if (err < 0) {
1456         return err;
1457     }
1458 
1459     u->postcopy_notifier.notify = vhost_user_postcopy_notifier;
1460     postcopy_add_notifier(&u->postcopy_notifier);
1461 
1462     return 0;
1463 }
1464 
1465 static int vhost_user_backend_cleanup(struct vhost_dev *dev)
1466 {
1467     struct vhost_user *u;
1468 
1469     assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
1470 
1471     u = dev->opaque;
1472     if (u->postcopy_notifier.notify) {
1473         postcopy_remove_notifier(&u->postcopy_notifier);
1474         u->postcopy_notifier.notify = NULL;
1475     }
1476     u->postcopy_listen = false;
1477     if (u->postcopy_fd.handler) {
1478         postcopy_unregister_shared_ufd(&u->postcopy_fd);
1479         close(u->postcopy_fd.fd);
1480         u->postcopy_fd.handler = NULL;
1481     }
1482     if (u->slave_fd >= 0) {
1483         qemu_set_fd_handler(u->slave_fd, NULL, NULL, NULL);
1484         close(u->slave_fd);
1485         u->slave_fd = -1;
1486     }
1487     g_free(u->region_rb);
1488     u->region_rb = NULL;
1489     g_free(u->region_rb_offset);
1490     u->region_rb_offset = NULL;
1491     u->region_rb_len = 0;
1492     g_free(u);
1493     dev->opaque = 0;
1494 
1495     return 0;
1496 }
1497 
1498 static int vhost_user_get_vq_index(struct vhost_dev *dev, int idx)
1499 {
1500     assert(idx >= dev->vq_index && idx < dev->vq_index + dev->nvqs);
1501 
1502     return idx;
1503 }
1504 
1505 static int vhost_user_memslots_limit(struct vhost_dev *dev)
1506 {
1507     return VHOST_MEMORY_MAX_NREGIONS;
1508 }
1509 
1510 static bool vhost_user_requires_shm_log(struct vhost_dev *dev)
1511 {
1512     assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
1513 
1514     return virtio_has_feature(dev->protocol_features,
1515                               VHOST_USER_PROTOCOL_F_LOG_SHMFD);
1516 }
1517 
1518 static int vhost_user_migration_done(struct vhost_dev *dev, char* mac_addr)
1519 {
1520     VhostUserMsg msg = { };
1521 
1522     assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
1523 
1524     /* If guest supports GUEST_ANNOUNCE do nothing */
1525     if (virtio_has_feature(dev->acked_features, VIRTIO_NET_F_GUEST_ANNOUNCE)) {
1526         return 0;
1527     }
1528 
1529     /* if backend supports VHOST_USER_PROTOCOL_F_RARP ask it to send the RARP */
1530     if (virtio_has_feature(dev->protocol_features,
1531                            VHOST_USER_PROTOCOL_F_RARP)) {
1532         msg.hdr.request = VHOST_USER_SEND_RARP;
1533         msg.hdr.flags = VHOST_USER_VERSION;
1534         memcpy((char *)&msg.payload.u64, mac_addr, 6);
1535         msg.hdr.size = sizeof(msg.payload.u64);
1536 
1537         return vhost_user_write(dev, &msg, NULL, 0);
1538     }
1539     return -1;
1540 }
1541 
1542 static bool vhost_user_can_merge(struct vhost_dev *dev,
1543                                  uint64_t start1, uint64_t size1,
1544                                  uint64_t start2, uint64_t size2)
1545 {
1546     ram_addr_t offset;
1547     int mfd, rfd;
1548     MemoryRegion *mr;
1549 
1550     mr = memory_region_from_host((void *)(uintptr_t)start1, &offset);
1551     mfd = memory_region_get_fd(mr);
1552 
1553     mr = memory_region_from_host((void *)(uintptr_t)start2, &offset);
1554     rfd = memory_region_get_fd(mr);
1555 
1556     return mfd == rfd;
1557 }
1558 
1559 static int vhost_user_net_set_mtu(struct vhost_dev *dev, uint16_t mtu)
1560 {
1561     VhostUserMsg msg;
1562     bool reply_supported = virtio_has_feature(dev->protocol_features,
1563                                               VHOST_USER_PROTOCOL_F_REPLY_ACK);
1564 
1565     if (!(dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_NET_MTU))) {
1566         return 0;
1567     }
1568 
1569     msg.hdr.request = VHOST_USER_NET_SET_MTU;
1570     msg.payload.u64 = mtu;
1571     msg.hdr.size = sizeof(msg.payload.u64);
1572     msg.hdr.flags = VHOST_USER_VERSION;
1573     if (reply_supported) {
1574         msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
1575     }
1576 
1577     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
1578         return -1;
1579     }
1580 
1581     /* If reply_ack supported, slave has to ack specified MTU is valid */
1582     if (reply_supported) {
1583         return process_message_reply(dev, &msg);
1584     }
1585 
1586     return 0;
1587 }
1588 
1589 static int vhost_user_send_device_iotlb_msg(struct vhost_dev *dev,
1590                                             struct vhost_iotlb_msg *imsg)
1591 {
1592     VhostUserMsg msg = {
1593         .hdr.request = VHOST_USER_IOTLB_MSG,
1594         .hdr.size = sizeof(msg.payload.iotlb),
1595         .hdr.flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK,
1596         .payload.iotlb = *imsg,
1597     };
1598 
1599     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
1600         return -EFAULT;
1601     }
1602 
1603     return process_message_reply(dev, &msg);
1604 }
1605 
1606 
1607 static void vhost_user_set_iotlb_callback(struct vhost_dev *dev, int enabled)
1608 {
1609     /* No-op as the receive channel is not dedicated to IOTLB messages. */
1610 }
1611 
1612 static int vhost_user_get_config(struct vhost_dev *dev, uint8_t *config,
1613                                  uint32_t config_len)
1614 {
1615     VhostUserMsg msg = {
1616         .hdr.request = VHOST_USER_GET_CONFIG,
1617         .hdr.flags = VHOST_USER_VERSION,
1618         .hdr.size = VHOST_USER_CONFIG_HDR_SIZE + config_len,
1619     };
1620 
1621     if (!virtio_has_feature(dev->protocol_features,
1622                 VHOST_USER_PROTOCOL_F_CONFIG)) {
1623         return -1;
1624     }
1625 
1626     if (config_len > VHOST_USER_MAX_CONFIG_SIZE) {
1627         return -1;
1628     }
1629 
1630     msg.payload.config.offset = 0;
1631     msg.payload.config.size = config_len;
1632     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
1633         return -1;
1634     }
1635 
1636     if (vhost_user_read(dev, &msg) < 0) {
1637         return -1;
1638     }
1639 
1640     if (msg.hdr.request != VHOST_USER_GET_CONFIG) {
1641         error_report("Received unexpected msg type. Expected %d received %d",
1642                      VHOST_USER_GET_CONFIG, msg.hdr.request);
1643         return -1;
1644     }
1645 
1646     if (msg.hdr.size != VHOST_USER_CONFIG_HDR_SIZE + config_len) {
1647         error_report("Received bad msg size.");
1648         return -1;
1649     }
1650 
1651     memcpy(config, msg.payload.config.region, config_len);
1652 
1653     return 0;
1654 }
1655 
1656 static int vhost_user_set_config(struct vhost_dev *dev, const uint8_t *data,
1657                                  uint32_t offset, uint32_t size, uint32_t flags)
1658 {
1659     uint8_t *p;
1660     bool reply_supported = virtio_has_feature(dev->protocol_features,
1661                                               VHOST_USER_PROTOCOL_F_REPLY_ACK);
1662 
1663     VhostUserMsg msg = {
1664         .hdr.request = VHOST_USER_SET_CONFIG,
1665         .hdr.flags = VHOST_USER_VERSION,
1666         .hdr.size = VHOST_USER_CONFIG_HDR_SIZE + size,
1667     };
1668 
1669     if (!virtio_has_feature(dev->protocol_features,
1670                 VHOST_USER_PROTOCOL_F_CONFIG)) {
1671         return -1;
1672     }
1673 
1674     if (reply_supported) {
1675         msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
1676     }
1677 
1678     if (size > VHOST_USER_MAX_CONFIG_SIZE) {
1679         return -1;
1680     }
1681 
1682     msg.payload.config.offset = offset,
1683     msg.payload.config.size = size,
1684     msg.payload.config.flags = flags,
1685     p = msg.payload.config.region;
1686     memcpy(p, data, size);
1687 
1688     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
1689         return -1;
1690     }
1691 
1692     if (reply_supported) {
1693         return process_message_reply(dev, &msg);
1694     }
1695 
1696     return 0;
1697 }
1698 
1699 static int vhost_user_crypto_create_session(struct vhost_dev *dev,
1700                                             void *session_info,
1701                                             uint64_t *session_id)
1702 {
1703     bool crypto_session = virtio_has_feature(dev->protocol_features,
1704                                        VHOST_USER_PROTOCOL_F_CRYPTO_SESSION);
1705     CryptoDevBackendSymSessionInfo *sess_info = session_info;
1706     VhostUserMsg msg = {
1707         .hdr.request = VHOST_USER_CREATE_CRYPTO_SESSION,
1708         .hdr.flags = VHOST_USER_VERSION,
1709         .hdr.size = sizeof(msg.payload.session),
1710     };
1711 
1712     assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
1713 
1714     if (!crypto_session) {
1715         error_report("vhost-user trying to send unhandled ioctl");
1716         return -1;
1717     }
1718 
1719     memcpy(&msg.payload.session.session_setup_data, sess_info,
1720               sizeof(CryptoDevBackendSymSessionInfo));
1721     if (sess_info->key_len) {
1722         memcpy(&msg.payload.session.key, sess_info->cipher_key,
1723                sess_info->key_len);
1724     }
1725     if (sess_info->auth_key_len > 0) {
1726         memcpy(&msg.payload.session.auth_key, sess_info->auth_key,
1727                sess_info->auth_key_len);
1728     }
1729     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
1730         error_report("vhost_user_write() return -1, create session failed");
1731         return -1;
1732     }
1733 
1734     if (vhost_user_read(dev, &msg) < 0) {
1735         error_report("vhost_user_read() return -1, create session failed");
1736         return -1;
1737     }
1738 
1739     if (msg.hdr.request != VHOST_USER_CREATE_CRYPTO_SESSION) {
1740         error_report("Received unexpected msg type. Expected %d received %d",
1741                      VHOST_USER_CREATE_CRYPTO_SESSION, msg.hdr.request);
1742         return -1;
1743     }
1744 
1745     if (msg.hdr.size != sizeof(msg.payload.session)) {
1746         error_report("Received bad msg size.");
1747         return -1;
1748     }
1749 
1750     if (msg.payload.session.session_id < 0) {
1751         error_report("Bad session id: %" PRId64 "",
1752                               msg.payload.session.session_id);
1753         return -1;
1754     }
1755     *session_id = msg.payload.session.session_id;
1756 
1757     return 0;
1758 }
1759 
1760 static int
1761 vhost_user_crypto_close_session(struct vhost_dev *dev, uint64_t session_id)
1762 {
1763     bool crypto_session = virtio_has_feature(dev->protocol_features,
1764                                        VHOST_USER_PROTOCOL_F_CRYPTO_SESSION);
1765     VhostUserMsg msg = {
1766         .hdr.request = VHOST_USER_CLOSE_CRYPTO_SESSION,
1767         .hdr.flags = VHOST_USER_VERSION,
1768         .hdr.size = sizeof(msg.payload.u64),
1769     };
1770     msg.payload.u64 = session_id;
1771 
1772     if (!crypto_session) {
1773         error_report("vhost-user trying to send unhandled ioctl");
1774         return -1;
1775     }
1776 
1777     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
1778         error_report("vhost_user_write() return -1, close session failed");
1779         return -1;
1780     }
1781 
1782     return 0;
1783 }
1784 
1785 static bool vhost_user_mem_section_filter(struct vhost_dev *dev,
1786                                           MemoryRegionSection *section)
1787 {
1788     bool result;
1789 
1790     result = memory_region_get_fd(section->mr) >= 0;
1791 
1792     return result;
1793 }
1794 
1795 static int vhost_user_get_inflight_fd(struct vhost_dev *dev,
1796                                       uint16_t queue_size,
1797                                       struct vhost_inflight *inflight)
1798 {
1799     void *addr;
1800     int fd;
1801     struct vhost_user *u = dev->opaque;
1802     CharBackend *chr = u->user->chr;
1803     VhostUserMsg msg = {
1804         .hdr.request = VHOST_USER_GET_INFLIGHT_FD,
1805         .hdr.flags = VHOST_USER_VERSION,
1806         .payload.inflight.num_queues = dev->nvqs,
1807         .payload.inflight.queue_size = queue_size,
1808         .hdr.size = sizeof(msg.payload.inflight),
1809     };
1810 
1811     if (!virtio_has_feature(dev->protocol_features,
1812                             VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) {
1813         return 0;
1814     }
1815 
1816     if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
1817         return -1;
1818     }
1819 
1820     if (vhost_user_read(dev, &msg) < 0) {
1821         return -1;
1822     }
1823 
1824     if (msg.hdr.request != VHOST_USER_GET_INFLIGHT_FD) {
1825         error_report("Received unexpected msg type. "
1826                      "Expected %d received %d",
1827                      VHOST_USER_GET_INFLIGHT_FD, msg.hdr.request);
1828         return -1;
1829     }
1830 
1831     if (msg.hdr.size != sizeof(msg.payload.inflight)) {
1832         error_report("Received bad msg size.");
1833         return -1;
1834     }
1835 
1836     if (!msg.payload.inflight.mmap_size) {
1837         return 0;
1838     }
1839 
1840     fd = qemu_chr_fe_get_msgfd(chr);
1841     if (fd < 0) {
1842         error_report("Failed to get mem fd");
1843         return -1;
1844     }
1845 
1846     addr = mmap(0, msg.payload.inflight.mmap_size, PROT_READ | PROT_WRITE,
1847                 MAP_SHARED, fd, msg.payload.inflight.mmap_offset);
1848 
1849     if (addr == MAP_FAILED) {
1850         error_report("Failed to mmap mem fd");
1851         close(fd);
1852         return -1;
1853     }
1854 
1855     inflight->addr = addr;
1856     inflight->fd = fd;
1857     inflight->size = msg.payload.inflight.mmap_size;
1858     inflight->offset = msg.payload.inflight.mmap_offset;
1859     inflight->queue_size = queue_size;
1860 
1861     return 0;
1862 }
1863 
1864 static int vhost_user_set_inflight_fd(struct vhost_dev *dev,
1865                                       struct vhost_inflight *inflight)
1866 {
1867     VhostUserMsg msg = {
1868         .hdr.request = VHOST_USER_SET_INFLIGHT_FD,
1869         .hdr.flags = VHOST_USER_VERSION,
1870         .payload.inflight.mmap_size = inflight->size,
1871         .payload.inflight.mmap_offset = inflight->offset,
1872         .payload.inflight.num_queues = dev->nvqs,
1873         .payload.inflight.queue_size = inflight->queue_size,
1874         .hdr.size = sizeof(msg.payload.inflight),
1875     };
1876 
1877     if (!virtio_has_feature(dev->protocol_features,
1878                             VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) {
1879         return 0;
1880     }
1881 
1882     if (vhost_user_write(dev, &msg, &inflight->fd, 1) < 0) {
1883         return -1;
1884     }
1885 
1886     return 0;
1887 }
1888 
1889 bool vhost_user_init(VhostUserState *user, CharBackend *chr, Error **errp)
1890 {
1891     if (user->chr) {
1892         error_setg(errp, "Cannot initialize vhost-user state");
1893         return false;
1894     }
1895     user->chr = chr;
1896     return true;
1897 }
1898 
1899 void vhost_user_cleanup(VhostUserState *user)
1900 {
1901     int i;
1902 
1903     if (!user->chr) {
1904         return;
1905     }
1906 
1907     for (i = 0; i < VIRTIO_QUEUE_MAX; i++) {
1908         if (user->notifier[i].addr) {
1909             object_unparent(OBJECT(&user->notifier[i].mr));
1910             munmap(user->notifier[i].addr, qemu_real_host_page_size);
1911             user->notifier[i].addr = NULL;
1912         }
1913     }
1914     user->chr = NULL;
1915 }
1916 
1917 const VhostOps user_ops = {
1918         .backend_type = VHOST_BACKEND_TYPE_USER,
1919         .vhost_backend_init = vhost_user_backend_init,
1920         .vhost_backend_cleanup = vhost_user_backend_cleanup,
1921         .vhost_backend_memslots_limit = vhost_user_memslots_limit,
1922         .vhost_set_log_base = vhost_user_set_log_base,
1923         .vhost_set_mem_table = vhost_user_set_mem_table,
1924         .vhost_set_vring_addr = vhost_user_set_vring_addr,
1925         .vhost_set_vring_endian = vhost_user_set_vring_endian,
1926         .vhost_set_vring_num = vhost_user_set_vring_num,
1927         .vhost_set_vring_base = vhost_user_set_vring_base,
1928         .vhost_get_vring_base = vhost_user_get_vring_base,
1929         .vhost_set_vring_kick = vhost_user_set_vring_kick,
1930         .vhost_set_vring_call = vhost_user_set_vring_call,
1931         .vhost_set_features = vhost_user_set_features,
1932         .vhost_get_features = vhost_user_get_features,
1933         .vhost_set_owner = vhost_user_set_owner,
1934         .vhost_reset_device = vhost_user_reset_device,
1935         .vhost_get_vq_index = vhost_user_get_vq_index,
1936         .vhost_set_vring_enable = vhost_user_set_vring_enable,
1937         .vhost_requires_shm_log = vhost_user_requires_shm_log,
1938         .vhost_migration_done = vhost_user_migration_done,
1939         .vhost_backend_can_merge = vhost_user_can_merge,
1940         .vhost_net_set_mtu = vhost_user_net_set_mtu,
1941         .vhost_set_iotlb_callback = vhost_user_set_iotlb_callback,
1942         .vhost_send_device_iotlb_msg = vhost_user_send_device_iotlb_msg,
1943         .vhost_get_config = vhost_user_get_config,
1944         .vhost_set_config = vhost_user_set_config,
1945         .vhost_crypto_create_session = vhost_user_crypto_create_session,
1946         .vhost_crypto_close_session = vhost_user_crypto_close_session,
1947         .vhost_backend_mem_section_filter = vhost_user_mem_section_filter,
1948         .vhost_get_inflight_fd = vhost_user_get_inflight_fd,
1949         .vhost_set_inflight_fd = vhost_user_set_inflight_fd,
1950 };
1951