xref: /openbmc/qemu/hw/virtio/vhost-user.c (revision 0fbb5d2d)
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 "io/channel-socket.h"
20 #include "sysemu/kvm.h"
21 #include "qemu/error-report.h"
22 #include "qemu/main-loop.h"
23 #include "qemu/sockets.h"
24 #include "sysemu/cryptodev.h"
25 #include "migration/migration.h"
26 #include "migration/postcopy-ram.h"
27 #include "trace.h"
28 
29 #include <sys/ioctl.h>
30 #include <sys/socket.h>
31 #include <sys/un.h>
32 
33 #include "standard-headers/linux/vhost_types.h"
34 
35 #ifdef CONFIG_LINUX
36 #include <linux/userfaultfd.h>
37 #endif
38 
39 #define VHOST_MEMORY_BASELINE_NREGIONS    8
40 #define VHOST_USER_F_PROTOCOL_FEATURES 30
41 #define VHOST_USER_SLAVE_MAX_FDS     8
42 
43 /*
44  * Set maximum number of RAM slots supported to
45  * the maximum number supported by the target
46  * hardware plaform.
47  */
48 #if defined(TARGET_X86) || defined(TARGET_X86_64) || \
49     defined(TARGET_ARM) || defined(TARGET_ARM_64)
50 #include "hw/acpi/acpi.h"
51 #define VHOST_USER_MAX_RAM_SLOTS ACPI_MAX_RAM_SLOTS
52 
53 #elif defined(TARGET_PPC) || defined(TARGET_PPC_64)
54 #include "hw/ppc/spapr.h"
55 #define VHOST_USER_MAX_RAM_SLOTS SPAPR_MAX_RAM_SLOTS
56 
57 #else
58 #define VHOST_USER_MAX_RAM_SLOTS 512
59 #endif
60 
61 /*
62  * Maximum size of virtio device config space
63  */
64 #define VHOST_USER_MAX_CONFIG_SIZE 256
65 
66 enum VhostUserProtocolFeature {
67     VHOST_USER_PROTOCOL_F_MQ = 0,
68     VHOST_USER_PROTOCOL_F_LOG_SHMFD = 1,
69     VHOST_USER_PROTOCOL_F_RARP = 2,
70     VHOST_USER_PROTOCOL_F_REPLY_ACK = 3,
71     VHOST_USER_PROTOCOL_F_NET_MTU = 4,
72     VHOST_USER_PROTOCOL_F_SLAVE_REQ = 5,
73     VHOST_USER_PROTOCOL_F_CROSS_ENDIAN = 6,
74     VHOST_USER_PROTOCOL_F_CRYPTO_SESSION = 7,
75     VHOST_USER_PROTOCOL_F_PAGEFAULT = 8,
76     VHOST_USER_PROTOCOL_F_CONFIG = 9,
77     VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD = 10,
78     VHOST_USER_PROTOCOL_F_HOST_NOTIFIER = 11,
79     VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD = 12,
80     VHOST_USER_PROTOCOL_F_RESET_DEVICE = 13,
81     /* Feature 14 reserved for VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS. */
82     VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS = 15,
83     VHOST_USER_PROTOCOL_F_MAX
84 };
85 
86 #define VHOST_USER_PROTOCOL_FEATURE_MASK ((1 << VHOST_USER_PROTOCOL_F_MAX) - 1)
87 
88 typedef enum VhostUserRequest {
89     VHOST_USER_NONE = 0,
90     VHOST_USER_GET_FEATURES = 1,
91     VHOST_USER_SET_FEATURES = 2,
92     VHOST_USER_SET_OWNER = 3,
93     VHOST_USER_RESET_OWNER = 4,
94     VHOST_USER_SET_MEM_TABLE = 5,
95     VHOST_USER_SET_LOG_BASE = 6,
96     VHOST_USER_SET_LOG_FD = 7,
97     VHOST_USER_SET_VRING_NUM = 8,
98     VHOST_USER_SET_VRING_ADDR = 9,
99     VHOST_USER_SET_VRING_BASE = 10,
100     VHOST_USER_GET_VRING_BASE = 11,
101     VHOST_USER_SET_VRING_KICK = 12,
102     VHOST_USER_SET_VRING_CALL = 13,
103     VHOST_USER_SET_VRING_ERR = 14,
104     VHOST_USER_GET_PROTOCOL_FEATURES = 15,
105     VHOST_USER_SET_PROTOCOL_FEATURES = 16,
106     VHOST_USER_GET_QUEUE_NUM = 17,
107     VHOST_USER_SET_VRING_ENABLE = 18,
108     VHOST_USER_SEND_RARP = 19,
109     VHOST_USER_NET_SET_MTU = 20,
110     VHOST_USER_SET_SLAVE_REQ_FD = 21,
111     VHOST_USER_IOTLB_MSG = 22,
112     VHOST_USER_SET_VRING_ENDIAN = 23,
113     VHOST_USER_GET_CONFIG = 24,
114     VHOST_USER_SET_CONFIG = 25,
115     VHOST_USER_CREATE_CRYPTO_SESSION = 26,
116     VHOST_USER_CLOSE_CRYPTO_SESSION = 27,
117     VHOST_USER_POSTCOPY_ADVISE  = 28,
118     VHOST_USER_POSTCOPY_LISTEN  = 29,
119     VHOST_USER_POSTCOPY_END     = 30,
120     VHOST_USER_GET_INFLIGHT_FD = 31,
121     VHOST_USER_SET_INFLIGHT_FD = 32,
122     VHOST_USER_GPU_SET_SOCKET = 33,
123     VHOST_USER_RESET_DEVICE = 34,
124     /* Message number 35 reserved for VHOST_USER_VRING_KICK. */
125     VHOST_USER_GET_MAX_MEM_SLOTS = 36,
126     VHOST_USER_ADD_MEM_REG = 37,
127     VHOST_USER_REM_MEM_REG = 38,
128     VHOST_USER_MAX
129 } VhostUserRequest;
130 
131 typedef enum VhostUserSlaveRequest {
132     VHOST_USER_SLAVE_NONE = 0,
133     VHOST_USER_SLAVE_IOTLB_MSG = 1,
134     VHOST_USER_SLAVE_CONFIG_CHANGE_MSG = 2,
135     VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = 3,
136     VHOST_USER_SLAVE_MAX
137 }  VhostUserSlaveRequest;
138 
139 typedef struct VhostUserMemoryRegion {
140     uint64_t guest_phys_addr;
141     uint64_t memory_size;
142     uint64_t userspace_addr;
143     uint64_t mmap_offset;
144 } VhostUserMemoryRegion;
145 
146 typedef struct VhostUserMemory {
147     uint32_t nregions;
148     uint32_t padding;
149     VhostUserMemoryRegion regions[VHOST_MEMORY_BASELINE_NREGIONS];
150 } VhostUserMemory;
151 
152 typedef struct VhostUserMemRegMsg {
153     uint64_t padding;
154     VhostUserMemoryRegion region;
155 } VhostUserMemRegMsg;
156 
157 typedef struct VhostUserLog {
158     uint64_t mmap_size;
159     uint64_t mmap_offset;
160 } VhostUserLog;
161 
162 typedef struct VhostUserConfig {
163     uint32_t offset;
164     uint32_t size;
165     uint32_t flags;
166     uint8_t region[VHOST_USER_MAX_CONFIG_SIZE];
167 } VhostUserConfig;
168 
169 #define VHOST_CRYPTO_SYM_HMAC_MAX_KEY_LEN    512
170 #define VHOST_CRYPTO_SYM_CIPHER_MAX_KEY_LEN  64
171 
172 typedef struct VhostUserCryptoSession {
173     /* session id for success, -1 on errors */
174     int64_t session_id;
175     CryptoDevBackendSymSessionInfo session_setup_data;
176     uint8_t key[VHOST_CRYPTO_SYM_CIPHER_MAX_KEY_LEN];
177     uint8_t auth_key[VHOST_CRYPTO_SYM_HMAC_MAX_KEY_LEN];
178 } VhostUserCryptoSession;
179 
180 static VhostUserConfig c __attribute__ ((unused));
181 #define VHOST_USER_CONFIG_HDR_SIZE (sizeof(c.offset) \
182                                    + sizeof(c.size) \
183                                    + sizeof(c.flags))
184 
185 typedef struct VhostUserVringArea {
186     uint64_t u64;
187     uint64_t size;
188     uint64_t offset;
189 } VhostUserVringArea;
190 
191 typedef struct VhostUserInflight {
192     uint64_t mmap_size;
193     uint64_t mmap_offset;
194     uint16_t num_queues;
195     uint16_t queue_size;
196 } VhostUserInflight;
197 
198 typedef struct {
199     VhostUserRequest request;
200 
201 #define VHOST_USER_VERSION_MASK     (0x3)
202 #define VHOST_USER_REPLY_MASK       (0x1<<2)
203 #define VHOST_USER_NEED_REPLY_MASK  (0x1 << 3)
204     uint32_t flags;
205     uint32_t size; /* the following payload size */
206 } QEMU_PACKED VhostUserHeader;
207 
208 typedef union {
209 #define VHOST_USER_VRING_IDX_MASK   (0xff)
210 #define VHOST_USER_VRING_NOFD_MASK  (0x1<<8)
211         uint64_t u64;
212         struct vhost_vring_state state;
213         struct vhost_vring_addr addr;
214         VhostUserMemory memory;
215         VhostUserMemRegMsg mem_reg;
216         VhostUserLog log;
217         struct vhost_iotlb_msg iotlb;
218         VhostUserConfig config;
219         VhostUserCryptoSession session;
220         VhostUserVringArea area;
221         VhostUserInflight inflight;
222 } VhostUserPayload;
223 
224 typedef struct VhostUserMsg {
225     VhostUserHeader hdr;
226     VhostUserPayload payload;
227 } QEMU_PACKED VhostUserMsg;
228 
229 static VhostUserMsg m __attribute__ ((unused));
230 #define VHOST_USER_HDR_SIZE (sizeof(VhostUserHeader))
231 
232 #define VHOST_USER_PAYLOAD_SIZE (sizeof(VhostUserPayload))
233 
234 /* The version of the protocol we support */
235 #define VHOST_USER_VERSION    (0x1)
236 
237 struct vhost_user {
238     struct vhost_dev *dev;
239     /* Shared between vhost devs of the same virtio device */
240     VhostUserState *user;
241     QIOChannel *slave_ioc;
242     GSource *slave_src;
243     NotifierWithReturn postcopy_notifier;
244     struct PostCopyFD  postcopy_fd;
245     uint64_t           postcopy_client_bases[VHOST_USER_MAX_RAM_SLOTS];
246     /* Length of the region_rb and region_rb_offset arrays */
247     size_t             region_rb_len;
248     /* RAMBlock associated with a given region */
249     RAMBlock         **region_rb;
250     /* The offset from the start of the RAMBlock to the start of the
251      * vhost region.
252      */
253     ram_addr_t        *region_rb_offset;
254 
255     /* True once we've entered postcopy_listen */
256     bool               postcopy_listen;
257 
258     /* Our current regions */
259     int num_shadow_regions;
260     struct vhost_memory_region shadow_regions[VHOST_USER_MAX_RAM_SLOTS];
261 };
262 
263 struct scrub_regions {
264     struct vhost_memory_region *region;
265     int reg_idx;
266     int fd_idx;
267 };
268 
269 static bool ioeventfd_enabled(void)
270 {
271     return !kvm_enabled() || kvm_eventfds_enabled();
272 }
273 
274 static int vhost_user_read_header(struct vhost_dev *dev, VhostUserMsg *msg)
275 {
276     struct vhost_user *u = dev->opaque;
277     CharBackend *chr = u->user->chr;
278     uint8_t *p = (uint8_t *) msg;
279     int r, size = VHOST_USER_HDR_SIZE;
280 
281     r = qemu_chr_fe_read_all(chr, p, size);
282     if (r != size) {
283         int saved_errno = errno;
284         error_report("Failed to read msg header. Read %d instead of %d."
285                      " Original request %d.", r, size, msg->hdr.request);
286         return r < 0 ? -saved_errno : -EIO;
287     }
288 
289     /* validate received flags */
290     if (msg->hdr.flags != (VHOST_USER_REPLY_MASK | VHOST_USER_VERSION)) {
291         error_report("Failed to read msg header."
292                 " Flags 0x%x instead of 0x%x.", msg->hdr.flags,
293                 VHOST_USER_REPLY_MASK | VHOST_USER_VERSION);
294         return -EPROTO;
295     }
296 
297     return 0;
298 }
299 
300 struct vhost_user_read_cb_data {
301     struct vhost_dev *dev;
302     VhostUserMsg *msg;
303     GMainLoop *loop;
304     int ret;
305 };
306 
307 static gboolean vhost_user_read_cb(void *do_not_use, GIOCondition condition,
308                                    gpointer opaque)
309 {
310     struct vhost_user_read_cb_data *data = opaque;
311     struct vhost_dev *dev = data->dev;
312     VhostUserMsg *msg = data->msg;
313     struct vhost_user *u = dev->opaque;
314     CharBackend *chr = u->user->chr;
315     uint8_t *p = (uint8_t *) msg;
316     int r, size;
317 
318     r = vhost_user_read_header(dev, msg);
319     if (r < 0) {
320         data->ret = r;
321         goto end;
322     }
323 
324     /* validate message size is sane */
325     if (msg->hdr.size > VHOST_USER_PAYLOAD_SIZE) {
326         error_report("Failed to read msg header."
327                 " Size %d exceeds the maximum %zu.", msg->hdr.size,
328                 VHOST_USER_PAYLOAD_SIZE);
329         data->ret = -EPROTO;
330         goto end;
331     }
332 
333     if (msg->hdr.size) {
334         p += VHOST_USER_HDR_SIZE;
335         size = msg->hdr.size;
336         r = qemu_chr_fe_read_all(chr, p, size);
337         if (r != size) {
338             int saved_errno = errno;
339             error_report("Failed to read msg payload."
340                          " Read %d instead of %d.", r, msg->hdr.size);
341             data->ret = r < 0 ? -saved_errno : -EIO;
342             goto end;
343         }
344     }
345 
346 end:
347     g_main_loop_quit(data->loop);
348     return G_SOURCE_REMOVE;
349 }
350 
351 static gboolean slave_read(QIOChannel *ioc, GIOCondition condition,
352                            gpointer opaque);
353 
354 /*
355  * This updates the read handler to use a new event loop context.
356  * Event sources are removed from the previous context : this ensures
357  * that events detected in the previous context are purged. They will
358  * be re-detected and processed in the new context.
359  */
360 static void slave_update_read_handler(struct vhost_dev *dev,
361                                       GMainContext *ctxt)
362 {
363     struct vhost_user *u = dev->opaque;
364 
365     if (!u->slave_ioc) {
366         return;
367     }
368 
369     if (u->slave_src) {
370         g_source_destroy(u->slave_src);
371         g_source_unref(u->slave_src);
372     }
373 
374     u->slave_src = qio_channel_add_watch_source(u->slave_ioc,
375                                                 G_IO_IN | G_IO_HUP,
376                                                 slave_read, dev, NULL,
377                                                 ctxt);
378 }
379 
380 static int vhost_user_read(struct vhost_dev *dev, VhostUserMsg *msg)
381 {
382     struct vhost_user *u = dev->opaque;
383     CharBackend *chr = u->user->chr;
384     GMainContext *prev_ctxt = chr->chr->gcontext;
385     GMainContext *ctxt = g_main_context_new();
386     GMainLoop *loop = g_main_loop_new(ctxt, FALSE);
387     struct vhost_user_read_cb_data data = {
388         .dev = dev,
389         .loop = loop,
390         .msg = msg,
391         .ret = 0
392     };
393 
394     /*
395      * We want to be able to monitor the slave channel fd while waiting
396      * for chr I/O. This requires an event loop, but we can't nest the
397      * one to which chr is currently attached : its fd handlers might not
398      * be prepared for re-entrancy. So we create a new one and switch chr
399      * to use it.
400      */
401     slave_update_read_handler(dev, ctxt);
402     qemu_chr_be_update_read_handlers(chr->chr, ctxt);
403     qemu_chr_fe_add_watch(chr, G_IO_IN | G_IO_HUP, vhost_user_read_cb, &data);
404 
405     g_main_loop_run(loop);
406 
407     /*
408      * Restore the previous event loop context. This also destroys/recreates
409      * event sources : this guarantees that all pending events in the original
410      * context that have been processed by the nested loop are purged.
411      */
412     qemu_chr_be_update_read_handlers(chr->chr, prev_ctxt);
413     slave_update_read_handler(dev, NULL);
414 
415     g_main_loop_unref(loop);
416     g_main_context_unref(ctxt);
417 
418     return data.ret;
419 }
420 
421 static int process_message_reply(struct vhost_dev *dev,
422                                  const VhostUserMsg *msg)
423 {
424     int ret;
425     VhostUserMsg msg_reply;
426 
427     if ((msg->hdr.flags & VHOST_USER_NEED_REPLY_MASK) == 0) {
428         return 0;
429     }
430 
431     ret = vhost_user_read(dev, &msg_reply);
432     if (ret < 0) {
433         return ret;
434     }
435 
436     if (msg_reply.hdr.request != msg->hdr.request) {
437         error_report("Received unexpected msg type. "
438                      "Expected %d received %d",
439                      msg->hdr.request, msg_reply.hdr.request);
440         return -EPROTO;
441     }
442 
443     return msg_reply.payload.u64 ? -EIO : 0;
444 }
445 
446 static bool vhost_user_one_time_request(VhostUserRequest request)
447 {
448     switch (request) {
449     case VHOST_USER_SET_OWNER:
450     case VHOST_USER_RESET_OWNER:
451     case VHOST_USER_SET_MEM_TABLE:
452     case VHOST_USER_GET_QUEUE_NUM:
453     case VHOST_USER_NET_SET_MTU:
454         return true;
455     default:
456         return false;
457     }
458 }
459 
460 /* most non-init callers ignore the error */
461 static int vhost_user_write(struct vhost_dev *dev, VhostUserMsg *msg,
462                             int *fds, int fd_num)
463 {
464     struct vhost_user *u = dev->opaque;
465     CharBackend *chr = u->user->chr;
466     int ret, size = VHOST_USER_HDR_SIZE + msg->hdr.size;
467 
468     /*
469      * For non-vring specific requests, like VHOST_USER_SET_MEM_TABLE,
470      * we just need send it once in the first time. For later such
471      * request, we just ignore it.
472      */
473     if (vhost_user_one_time_request(msg->hdr.request) && dev->vq_index != 0) {
474         msg->hdr.flags &= ~VHOST_USER_NEED_REPLY_MASK;
475         return 0;
476     }
477 
478     if (qemu_chr_fe_set_msgfds(chr, fds, fd_num) < 0) {
479         error_report("Failed to set msg fds.");
480         return -EINVAL;
481     }
482 
483     ret = qemu_chr_fe_write_all(chr, (const uint8_t *) msg, size);
484     if (ret != size) {
485         int saved_errno = errno;
486         error_report("Failed to write msg."
487                      " Wrote %d instead of %d.", ret, size);
488         return ret < 0 ? -saved_errno : -EIO;
489     }
490 
491     return 0;
492 }
493 
494 int vhost_user_gpu_set_socket(struct vhost_dev *dev, int fd)
495 {
496     VhostUserMsg msg = {
497         .hdr.request = VHOST_USER_GPU_SET_SOCKET,
498         .hdr.flags = VHOST_USER_VERSION,
499     };
500 
501     return vhost_user_write(dev, &msg, &fd, 1);
502 }
503 
504 static int vhost_user_set_log_base(struct vhost_dev *dev, uint64_t base,
505                                    struct vhost_log *log)
506 {
507     int fds[VHOST_USER_MAX_RAM_SLOTS];
508     size_t fd_num = 0;
509     bool shmfd = virtio_has_feature(dev->protocol_features,
510                                     VHOST_USER_PROTOCOL_F_LOG_SHMFD);
511     int ret;
512     VhostUserMsg msg = {
513         .hdr.request = VHOST_USER_SET_LOG_BASE,
514         .hdr.flags = VHOST_USER_VERSION,
515         .payload.log.mmap_size = log->size * sizeof(*(log->log)),
516         .payload.log.mmap_offset = 0,
517         .hdr.size = sizeof(msg.payload.log),
518     };
519 
520     if (shmfd && log->fd != -1) {
521         fds[fd_num++] = log->fd;
522     }
523 
524     ret = vhost_user_write(dev, &msg, fds, fd_num);
525     if (ret < 0) {
526         return ret;
527     }
528 
529     if (shmfd) {
530         msg.hdr.size = 0;
531         ret = vhost_user_read(dev, &msg);
532         if (ret < 0) {
533             return ret;
534         }
535 
536         if (msg.hdr.request != VHOST_USER_SET_LOG_BASE) {
537             error_report("Received unexpected msg type. "
538                          "Expected %d received %d",
539                          VHOST_USER_SET_LOG_BASE, msg.hdr.request);
540             return -EPROTO;
541         }
542     }
543 
544     return 0;
545 }
546 
547 static MemoryRegion *vhost_user_get_mr_data(uint64_t addr, ram_addr_t *offset,
548                                             int *fd)
549 {
550     MemoryRegion *mr;
551 
552     assert((uintptr_t)addr == addr);
553     mr = memory_region_from_host((void *)(uintptr_t)addr, offset);
554     *fd = memory_region_get_fd(mr);
555 
556     return mr;
557 }
558 
559 static void vhost_user_fill_msg_region(VhostUserMemoryRegion *dst,
560                                        struct vhost_memory_region *src,
561                                        uint64_t mmap_offset)
562 {
563     assert(src != NULL && dst != NULL);
564     dst->userspace_addr = src->userspace_addr;
565     dst->memory_size = src->memory_size;
566     dst->guest_phys_addr = src->guest_phys_addr;
567     dst->mmap_offset = mmap_offset;
568 }
569 
570 static int vhost_user_fill_set_mem_table_msg(struct vhost_user *u,
571                                              struct vhost_dev *dev,
572                                              VhostUserMsg *msg,
573                                              int *fds, size_t *fd_num,
574                                              bool track_ramblocks)
575 {
576     int i, fd;
577     ram_addr_t offset;
578     MemoryRegion *mr;
579     struct vhost_memory_region *reg;
580     VhostUserMemoryRegion region_buffer;
581 
582     msg->hdr.request = VHOST_USER_SET_MEM_TABLE;
583 
584     for (i = 0; i < dev->mem->nregions; ++i) {
585         reg = dev->mem->regions + i;
586 
587         mr = vhost_user_get_mr_data(reg->userspace_addr, &offset, &fd);
588         if (fd > 0) {
589             if (track_ramblocks) {
590                 assert(*fd_num < VHOST_MEMORY_BASELINE_NREGIONS);
591                 trace_vhost_user_set_mem_table_withfd(*fd_num, mr->name,
592                                                       reg->memory_size,
593                                                       reg->guest_phys_addr,
594                                                       reg->userspace_addr,
595                                                       offset);
596                 u->region_rb_offset[i] = offset;
597                 u->region_rb[i] = mr->ram_block;
598             } else if (*fd_num == VHOST_MEMORY_BASELINE_NREGIONS) {
599                 error_report("Failed preparing vhost-user memory table msg");
600                 return -ENOBUFS;
601             }
602             vhost_user_fill_msg_region(&region_buffer, reg, offset);
603             msg->payload.memory.regions[*fd_num] = region_buffer;
604             fds[(*fd_num)++] = fd;
605         } else if (track_ramblocks) {
606             u->region_rb_offset[i] = 0;
607             u->region_rb[i] = NULL;
608         }
609     }
610 
611     msg->payload.memory.nregions = *fd_num;
612 
613     if (!*fd_num) {
614         error_report("Failed initializing vhost-user memory map, "
615                      "consider using -object memory-backend-file share=on");
616         return -EINVAL;
617     }
618 
619     msg->hdr.size = sizeof(msg->payload.memory.nregions);
620     msg->hdr.size += sizeof(msg->payload.memory.padding);
621     msg->hdr.size += *fd_num * sizeof(VhostUserMemoryRegion);
622 
623     return 0;
624 }
625 
626 static inline bool reg_equal(struct vhost_memory_region *shadow_reg,
627                              struct vhost_memory_region *vdev_reg)
628 {
629     return shadow_reg->guest_phys_addr == vdev_reg->guest_phys_addr &&
630         shadow_reg->userspace_addr == vdev_reg->userspace_addr &&
631         shadow_reg->memory_size == vdev_reg->memory_size;
632 }
633 
634 static void scrub_shadow_regions(struct vhost_dev *dev,
635                                  struct scrub_regions *add_reg,
636                                  int *nr_add_reg,
637                                  struct scrub_regions *rem_reg,
638                                  int *nr_rem_reg, uint64_t *shadow_pcb,
639                                  bool track_ramblocks)
640 {
641     struct vhost_user *u = dev->opaque;
642     bool found[VHOST_USER_MAX_RAM_SLOTS] = {};
643     struct vhost_memory_region *reg, *shadow_reg;
644     int i, j, fd, add_idx = 0, rm_idx = 0, fd_num = 0;
645     ram_addr_t offset;
646     MemoryRegion *mr;
647     bool matching;
648 
649     /*
650      * Find memory regions present in our shadow state which are not in
651      * the device's current memory state.
652      *
653      * Mark regions in both the shadow and device state as "found".
654      */
655     for (i = 0; i < u->num_shadow_regions; i++) {
656         shadow_reg = &u->shadow_regions[i];
657         matching = false;
658 
659         for (j = 0; j < dev->mem->nregions; j++) {
660             reg = &dev->mem->regions[j];
661 
662             mr = vhost_user_get_mr_data(reg->userspace_addr, &offset, &fd);
663 
664             if (reg_equal(shadow_reg, reg)) {
665                 matching = true;
666                 found[j] = true;
667                 if (track_ramblocks) {
668                     /*
669                      * Reset postcopy client bases, region_rb, and
670                      * region_rb_offset in case regions are removed.
671                      */
672                     if (fd > 0) {
673                         u->region_rb_offset[j] = offset;
674                         u->region_rb[j] = mr->ram_block;
675                         shadow_pcb[j] = u->postcopy_client_bases[i];
676                     } else {
677                         u->region_rb_offset[j] = 0;
678                         u->region_rb[j] = NULL;
679                     }
680                 }
681                 break;
682             }
683         }
684 
685         /*
686          * If the region was not found in the current device memory state
687          * create an entry for it in the removed list.
688          */
689         if (!matching) {
690             rem_reg[rm_idx].region = shadow_reg;
691             rem_reg[rm_idx++].reg_idx = i;
692         }
693     }
694 
695     /*
696      * For regions not marked "found", create entries in the added list.
697      *
698      * Note their indexes in the device memory state and the indexes of their
699      * file descriptors.
700      */
701     for (i = 0; i < dev->mem->nregions; i++) {
702         reg = &dev->mem->regions[i];
703         vhost_user_get_mr_data(reg->userspace_addr, &offset, &fd);
704         if (fd > 0) {
705             ++fd_num;
706         }
707 
708         /*
709          * If the region was in both the shadow and device state we don't
710          * need to send a VHOST_USER_ADD_MEM_REG message for it.
711          */
712         if (found[i]) {
713             continue;
714         }
715 
716         add_reg[add_idx].region = reg;
717         add_reg[add_idx].reg_idx = i;
718         add_reg[add_idx++].fd_idx = fd_num;
719     }
720     *nr_rem_reg = rm_idx;
721     *nr_add_reg = add_idx;
722 
723     return;
724 }
725 
726 static int send_remove_regions(struct vhost_dev *dev,
727                                struct scrub_regions *remove_reg,
728                                int nr_rem_reg, VhostUserMsg *msg,
729                                bool reply_supported)
730 {
731     struct vhost_user *u = dev->opaque;
732     struct vhost_memory_region *shadow_reg;
733     int i, fd, shadow_reg_idx, ret;
734     ram_addr_t offset;
735     VhostUserMemoryRegion region_buffer;
736 
737     /*
738      * The regions in remove_reg appear in the same order they do in the
739      * shadow table. Therefore we can minimize memory copies by iterating
740      * through remove_reg backwards.
741      */
742     for (i = nr_rem_reg - 1; i >= 0; i--) {
743         shadow_reg = remove_reg[i].region;
744         shadow_reg_idx = remove_reg[i].reg_idx;
745 
746         vhost_user_get_mr_data(shadow_reg->userspace_addr, &offset, &fd);
747 
748         if (fd > 0) {
749             msg->hdr.request = VHOST_USER_REM_MEM_REG;
750             vhost_user_fill_msg_region(&region_buffer, shadow_reg, 0);
751             msg->payload.mem_reg.region = region_buffer;
752 
753             ret = vhost_user_write(dev, msg, &fd, 1);
754             if (ret < 0) {
755                 return ret;
756             }
757 
758             if (reply_supported) {
759                 ret = process_message_reply(dev, msg);
760                 if (ret) {
761                     return ret;
762                 }
763             }
764         }
765 
766         /*
767          * At this point we know the backend has unmapped the region. It is now
768          * safe to remove it from the shadow table.
769          */
770         memmove(&u->shadow_regions[shadow_reg_idx],
771                 &u->shadow_regions[shadow_reg_idx + 1],
772                 sizeof(struct vhost_memory_region) *
773                 (u->num_shadow_regions - shadow_reg_idx - 1));
774         u->num_shadow_regions--;
775     }
776 
777     return 0;
778 }
779 
780 static int send_add_regions(struct vhost_dev *dev,
781                             struct scrub_regions *add_reg, int nr_add_reg,
782                             VhostUserMsg *msg, uint64_t *shadow_pcb,
783                             bool reply_supported, bool track_ramblocks)
784 {
785     struct vhost_user *u = dev->opaque;
786     int i, fd, ret, reg_idx, reg_fd_idx;
787     struct vhost_memory_region *reg;
788     MemoryRegion *mr;
789     ram_addr_t offset;
790     VhostUserMsg msg_reply;
791     VhostUserMemoryRegion region_buffer;
792 
793     for (i = 0; i < nr_add_reg; i++) {
794         reg = add_reg[i].region;
795         reg_idx = add_reg[i].reg_idx;
796         reg_fd_idx = add_reg[i].fd_idx;
797 
798         mr = vhost_user_get_mr_data(reg->userspace_addr, &offset, &fd);
799 
800         if (fd > 0) {
801             if (track_ramblocks) {
802                 trace_vhost_user_set_mem_table_withfd(reg_fd_idx, mr->name,
803                                                       reg->memory_size,
804                                                       reg->guest_phys_addr,
805                                                       reg->userspace_addr,
806                                                       offset);
807                 u->region_rb_offset[reg_idx] = offset;
808                 u->region_rb[reg_idx] = mr->ram_block;
809             }
810             msg->hdr.request = VHOST_USER_ADD_MEM_REG;
811             vhost_user_fill_msg_region(&region_buffer, reg, offset);
812             msg->payload.mem_reg.region = region_buffer;
813 
814             ret = vhost_user_write(dev, msg, &fd, 1);
815             if (ret < 0) {
816                 return ret;
817             }
818 
819             if (track_ramblocks) {
820                 uint64_t reply_gpa;
821 
822                 ret = vhost_user_read(dev, &msg_reply);
823                 if (ret < 0) {
824                     return ret;
825                 }
826 
827                 reply_gpa = msg_reply.payload.mem_reg.region.guest_phys_addr;
828 
829                 if (msg_reply.hdr.request != VHOST_USER_ADD_MEM_REG) {
830                     error_report("%s: Received unexpected msg type."
831                                  "Expected %d received %d", __func__,
832                                  VHOST_USER_ADD_MEM_REG,
833                                  msg_reply.hdr.request);
834                     return -EPROTO;
835                 }
836 
837                 /*
838                  * We're using the same structure, just reusing one of the
839                  * fields, so it should be the same size.
840                  */
841                 if (msg_reply.hdr.size != msg->hdr.size) {
842                     error_report("%s: Unexpected size for postcopy reply "
843                                  "%d vs %d", __func__, msg_reply.hdr.size,
844                                  msg->hdr.size);
845                     return -EPROTO;
846                 }
847 
848                 /* Get the postcopy client base from the backend's reply. */
849                 if (reply_gpa == dev->mem->regions[reg_idx].guest_phys_addr) {
850                     shadow_pcb[reg_idx] =
851                         msg_reply.payload.mem_reg.region.userspace_addr;
852                     trace_vhost_user_set_mem_table_postcopy(
853                         msg_reply.payload.mem_reg.region.userspace_addr,
854                         msg->payload.mem_reg.region.userspace_addr,
855                         reg_fd_idx, reg_idx);
856                 } else {
857                     error_report("%s: invalid postcopy reply for region. "
858                                  "Got guest physical address %" PRIX64 ", expected "
859                                  "%" PRIX64, __func__, reply_gpa,
860                                  dev->mem->regions[reg_idx].guest_phys_addr);
861                     return -EPROTO;
862                 }
863             } else if (reply_supported) {
864                 ret = process_message_reply(dev, msg);
865                 if (ret) {
866                     return ret;
867                 }
868             }
869         } else if (track_ramblocks) {
870             u->region_rb_offset[reg_idx] = 0;
871             u->region_rb[reg_idx] = NULL;
872         }
873 
874         /*
875          * At this point, we know the backend has mapped in the new
876          * region, if the region has a valid file descriptor.
877          *
878          * The region should now be added to the shadow table.
879          */
880         u->shadow_regions[u->num_shadow_regions].guest_phys_addr =
881             reg->guest_phys_addr;
882         u->shadow_regions[u->num_shadow_regions].userspace_addr =
883             reg->userspace_addr;
884         u->shadow_regions[u->num_shadow_regions].memory_size =
885             reg->memory_size;
886         u->num_shadow_regions++;
887     }
888 
889     return 0;
890 }
891 
892 static int vhost_user_add_remove_regions(struct vhost_dev *dev,
893                                          VhostUserMsg *msg,
894                                          bool reply_supported,
895                                          bool track_ramblocks)
896 {
897     struct vhost_user *u = dev->opaque;
898     struct scrub_regions add_reg[VHOST_USER_MAX_RAM_SLOTS];
899     struct scrub_regions rem_reg[VHOST_USER_MAX_RAM_SLOTS];
900     uint64_t shadow_pcb[VHOST_USER_MAX_RAM_SLOTS] = {};
901     int nr_add_reg, nr_rem_reg;
902     int ret;
903 
904     msg->hdr.size = sizeof(msg->payload.mem_reg);
905 
906     /* Find the regions which need to be removed or added. */
907     scrub_shadow_regions(dev, add_reg, &nr_add_reg, rem_reg, &nr_rem_reg,
908                          shadow_pcb, track_ramblocks);
909 
910     if (nr_rem_reg) {
911         ret = send_remove_regions(dev, rem_reg, nr_rem_reg, msg,
912                                   reply_supported);
913         if (ret < 0) {
914             goto err;
915         }
916     }
917 
918     if (nr_add_reg) {
919         ret = send_add_regions(dev, add_reg, nr_add_reg, msg, shadow_pcb,
920                                reply_supported, track_ramblocks);
921         if (ret < 0) {
922             goto err;
923         }
924     }
925 
926     if (track_ramblocks) {
927         memcpy(u->postcopy_client_bases, shadow_pcb,
928                sizeof(uint64_t) * VHOST_USER_MAX_RAM_SLOTS);
929         /*
930          * Now we've registered this with the postcopy code, we ack to the
931          * client, because now we're in the position to be able to deal with
932          * any faults it generates.
933          */
934         /* TODO: Use this for failure cases as well with a bad value. */
935         msg->hdr.size = sizeof(msg->payload.u64);
936         msg->payload.u64 = 0; /* OK */
937 
938         ret = vhost_user_write(dev, msg, NULL, 0);
939         if (ret < 0) {
940             return ret;
941         }
942     }
943 
944     return 0;
945 
946 err:
947     if (track_ramblocks) {
948         memcpy(u->postcopy_client_bases, shadow_pcb,
949                sizeof(uint64_t) * VHOST_USER_MAX_RAM_SLOTS);
950     }
951 
952     return ret;
953 }
954 
955 static int vhost_user_set_mem_table_postcopy(struct vhost_dev *dev,
956                                              struct vhost_memory *mem,
957                                              bool reply_supported,
958                                              bool config_mem_slots)
959 {
960     struct vhost_user *u = dev->opaque;
961     int fds[VHOST_MEMORY_BASELINE_NREGIONS];
962     size_t fd_num = 0;
963     VhostUserMsg msg_reply;
964     int region_i, msg_i;
965     int ret;
966 
967     VhostUserMsg msg = {
968         .hdr.flags = VHOST_USER_VERSION,
969     };
970 
971     if (u->region_rb_len < dev->mem->nregions) {
972         u->region_rb = g_renew(RAMBlock*, u->region_rb, dev->mem->nregions);
973         u->region_rb_offset = g_renew(ram_addr_t, u->region_rb_offset,
974                                       dev->mem->nregions);
975         memset(&(u->region_rb[u->region_rb_len]), '\0',
976                sizeof(RAMBlock *) * (dev->mem->nregions - u->region_rb_len));
977         memset(&(u->region_rb_offset[u->region_rb_len]), '\0',
978                sizeof(ram_addr_t) * (dev->mem->nregions - u->region_rb_len));
979         u->region_rb_len = dev->mem->nregions;
980     }
981 
982     if (config_mem_slots) {
983         ret = vhost_user_add_remove_regions(dev, &msg, reply_supported, true);
984         if (ret < 0) {
985             return ret;
986         }
987     } else {
988         ret = vhost_user_fill_set_mem_table_msg(u, dev, &msg, fds, &fd_num,
989                                                 true);
990         if (ret < 0) {
991             return ret;
992         }
993 
994         ret = vhost_user_write(dev, &msg, fds, fd_num);
995         if (ret < 0) {
996             return ret;
997         }
998 
999         ret = vhost_user_read(dev, &msg_reply);
1000         if (ret < 0) {
1001             return ret;
1002         }
1003 
1004         if (msg_reply.hdr.request != VHOST_USER_SET_MEM_TABLE) {
1005             error_report("%s: Received unexpected msg type."
1006                          "Expected %d received %d", __func__,
1007                          VHOST_USER_SET_MEM_TABLE, msg_reply.hdr.request);
1008             return -EPROTO;
1009         }
1010 
1011         /*
1012          * We're using the same structure, just reusing one of the
1013          * fields, so it should be the same size.
1014          */
1015         if (msg_reply.hdr.size != msg.hdr.size) {
1016             error_report("%s: Unexpected size for postcopy reply "
1017                          "%d vs %d", __func__, msg_reply.hdr.size,
1018                          msg.hdr.size);
1019             return -EPROTO;
1020         }
1021 
1022         memset(u->postcopy_client_bases, 0,
1023                sizeof(uint64_t) * VHOST_USER_MAX_RAM_SLOTS);
1024 
1025         /*
1026          * They're in the same order as the regions that were sent
1027          * but some of the regions were skipped (above) if they
1028          * didn't have fd's
1029          */
1030         for (msg_i = 0, region_i = 0;
1031              region_i < dev->mem->nregions;
1032              region_i++) {
1033             if (msg_i < fd_num &&
1034                 msg_reply.payload.memory.regions[msg_i].guest_phys_addr ==
1035                 dev->mem->regions[region_i].guest_phys_addr) {
1036                 u->postcopy_client_bases[region_i] =
1037                     msg_reply.payload.memory.regions[msg_i].userspace_addr;
1038                 trace_vhost_user_set_mem_table_postcopy(
1039                     msg_reply.payload.memory.regions[msg_i].userspace_addr,
1040                     msg.payload.memory.regions[msg_i].userspace_addr,
1041                     msg_i, region_i);
1042                 msg_i++;
1043             }
1044         }
1045         if (msg_i != fd_num) {
1046             error_report("%s: postcopy reply not fully consumed "
1047                          "%d vs %zd",
1048                          __func__, msg_i, fd_num);
1049             return -EIO;
1050         }
1051 
1052         /*
1053          * Now we've registered this with the postcopy code, we ack to the
1054          * client, because now we're in the position to be able to deal
1055          * with any faults it generates.
1056          */
1057         /* TODO: Use this for failure cases as well with a bad value. */
1058         msg.hdr.size = sizeof(msg.payload.u64);
1059         msg.payload.u64 = 0; /* OK */
1060         ret = vhost_user_write(dev, &msg, NULL, 0);
1061         if (ret < 0) {
1062             return ret;
1063         }
1064     }
1065 
1066     return 0;
1067 }
1068 
1069 static int vhost_user_set_mem_table(struct vhost_dev *dev,
1070                                     struct vhost_memory *mem)
1071 {
1072     struct vhost_user *u = dev->opaque;
1073     int fds[VHOST_MEMORY_BASELINE_NREGIONS];
1074     size_t fd_num = 0;
1075     bool do_postcopy = u->postcopy_listen && u->postcopy_fd.handler;
1076     bool reply_supported = virtio_has_feature(dev->protocol_features,
1077                                               VHOST_USER_PROTOCOL_F_REPLY_ACK);
1078     bool config_mem_slots =
1079         virtio_has_feature(dev->protocol_features,
1080                            VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS);
1081     int ret;
1082 
1083     if (do_postcopy) {
1084         /*
1085          * Postcopy has enough differences that it's best done in it's own
1086          * version
1087          */
1088         return vhost_user_set_mem_table_postcopy(dev, mem, reply_supported,
1089                                                  config_mem_slots);
1090     }
1091 
1092     VhostUserMsg msg = {
1093         .hdr.flags = VHOST_USER_VERSION,
1094     };
1095 
1096     if (reply_supported) {
1097         msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
1098     }
1099 
1100     if (config_mem_slots) {
1101         ret = vhost_user_add_remove_regions(dev, &msg, reply_supported, false);
1102         if (ret < 0) {
1103             return ret;
1104         }
1105     } else {
1106         ret = vhost_user_fill_set_mem_table_msg(u, dev, &msg, fds, &fd_num,
1107                                                 false);
1108         if (ret < 0) {
1109             return ret;
1110         }
1111 
1112         ret = vhost_user_write(dev, &msg, fds, fd_num);
1113         if (ret < 0) {
1114             return ret;
1115         }
1116 
1117         if (reply_supported) {
1118             return process_message_reply(dev, &msg);
1119         }
1120     }
1121 
1122     return 0;
1123 }
1124 
1125 static int vhost_user_set_vring_endian(struct vhost_dev *dev,
1126                                        struct vhost_vring_state *ring)
1127 {
1128     bool cross_endian = virtio_has_feature(dev->protocol_features,
1129                                            VHOST_USER_PROTOCOL_F_CROSS_ENDIAN);
1130     VhostUserMsg msg = {
1131         .hdr.request = VHOST_USER_SET_VRING_ENDIAN,
1132         .hdr.flags = VHOST_USER_VERSION,
1133         .payload.state = *ring,
1134         .hdr.size = sizeof(msg.payload.state),
1135     };
1136 
1137     if (!cross_endian) {
1138         error_report("vhost-user trying to send unhandled ioctl");
1139         return -ENOTSUP;
1140     }
1141 
1142     return vhost_user_write(dev, &msg, NULL, 0);
1143 }
1144 
1145 static int vhost_set_vring(struct vhost_dev *dev,
1146                            unsigned long int request,
1147                            struct vhost_vring_state *ring)
1148 {
1149     VhostUserMsg msg = {
1150         .hdr.request = request,
1151         .hdr.flags = VHOST_USER_VERSION,
1152         .payload.state = *ring,
1153         .hdr.size = sizeof(msg.payload.state),
1154     };
1155 
1156     return vhost_user_write(dev, &msg, NULL, 0);
1157 }
1158 
1159 static int vhost_user_set_vring_num(struct vhost_dev *dev,
1160                                     struct vhost_vring_state *ring)
1161 {
1162     return vhost_set_vring(dev, VHOST_USER_SET_VRING_NUM, ring);
1163 }
1164 
1165 static void vhost_user_host_notifier_restore(struct vhost_dev *dev,
1166                                              int queue_idx)
1167 {
1168     struct vhost_user *u = dev->opaque;
1169     VhostUserHostNotifier *n = &u->user->notifier[queue_idx];
1170     VirtIODevice *vdev = dev->vdev;
1171 
1172     if (n->addr && !n->set) {
1173         virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, true);
1174         n->set = true;
1175     }
1176 }
1177 
1178 static void vhost_user_host_notifier_remove(struct vhost_dev *dev,
1179                                             int queue_idx)
1180 {
1181     struct vhost_user *u = dev->opaque;
1182     VhostUserHostNotifier *n = &u->user->notifier[queue_idx];
1183     VirtIODevice *vdev = dev->vdev;
1184 
1185     if (n->addr && n->set) {
1186         virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, false);
1187         n->set = false;
1188     }
1189 }
1190 
1191 static int vhost_user_set_vring_base(struct vhost_dev *dev,
1192                                      struct vhost_vring_state *ring)
1193 {
1194     vhost_user_host_notifier_restore(dev, ring->index);
1195 
1196     return vhost_set_vring(dev, VHOST_USER_SET_VRING_BASE, ring);
1197 }
1198 
1199 static int vhost_user_set_vring_enable(struct vhost_dev *dev, int enable)
1200 {
1201     int i;
1202 
1203     if (!virtio_has_feature(dev->features, VHOST_USER_F_PROTOCOL_FEATURES)) {
1204         return -EINVAL;
1205     }
1206 
1207     for (i = 0; i < dev->nvqs; ++i) {
1208         int ret;
1209         struct vhost_vring_state state = {
1210             .index = dev->vq_index + i,
1211             .num   = enable,
1212         };
1213 
1214         ret = vhost_set_vring(dev, VHOST_USER_SET_VRING_ENABLE, &state);
1215         if (ret < 0) {
1216             /*
1217              * Restoring the previous state is likely infeasible, as well as
1218              * proceeding regardless the error, so just bail out and hope for
1219              * the device-level recovery.
1220              */
1221             return ret;
1222         }
1223     }
1224 
1225     return 0;
1226 }
1227 
1228 static int vhost_user_get_vring_base(struct vhost_dev *dev,
1229                                      struct vhost_vring_state *ring)
1230 {
1231     int ret;
1232     VhostUserMsg msg = {
1233         .hdr.request = VHOST_USER_GET_VRING_BASE,
1234         .hdr.flags = VHOST_USER_VERSION,
1235         .payload.state = *ring,
1236         .hdr.size = sizeof(msg.payload.state),
1237     };
1238 
1239     vhost_user_host_notifier_remove(dev, ring->index);
1240 
1241     ret = vhost_user_write(dev, &msg, NULL, 0);
1242     if (ret < 0) {
1243         return ret;
1244     }
1245 
1246     ret = vhost_user_read(dev, &msg);
1247     if (ret < 0) {
1248         return ret;
1249     }
1250 
1251     if (msg.hdr.request != VHOST_USER_GET_VRING_BASE) {
1252         error_report("Received unexpected msg type. Expected %d received %d",
1253                      VHOST_USER_GET_VRING_BASE, msg.hdr.request);
1254         return -EPROTO;
1255     }
1256 
1257     if (msg.hdr.size != sizeof(msg.payload.state)) {
1258         error_report("Received bad msg size.");
1259         return -EPROTO;
1260     }
1261 
1262     *ring = msg.payload.state;
1263 
1264     return 0;
1265 }
1266 
1267 static int vhost_set_vring_file(struct vhost_dev *dev,
1268                                 VhostUserRequest request,
1269                                 struct vhost_vring_file *file)
1270 {
1271     int fds[VHOST_USER_MAX_RAM_SLOTS];
1272     size_t fd_num = 0;
1273     VhostUserMsg msg = {
1274         .hdr.request = request,
1275         .hdr.flags = VHOST_USER_VERSION,
1276         .payload.u64 = file->index & VHOST_USER_VRING_IDX_MASK,
1277         .hdr.size = sizeof(msg.payload.u64),
1278     };
1279 
1280     if (ioeventfd_enabled() && file->fd > 0) {
1281         fds[fd_num++] = file->fd;
1282     } else {
1283         msg.payload.u64 |= VHOST_USER_VRING_NOFD_MASK;
1284     }
1285 
1286     return vhost_user_write(dev, &msg, fds, fd_num);
1287 }
1288 
1289 static int vhost_user_set_vring_kick(struct vhost_dev *dev,
1290                                      struct vhost_vring_file *file)
1291 {
1292     return vhost_set_vring_file(dev, VHOST_USER_SET_VRING_KICK, file);
1293 }
1294 
1295 static int vhost_user_set_vring_call(struct vhost_dev *dev,
1296                                      struct vhost_vring_file *file)
1297 {
1298     return vhost_set_vring_file(dev, VHOST_USER_SET_VRING_CALL, file);
1299 }
1300 
1301 
1302 static int vhost_user_get_u64(struct vhost_dev *dev, int request, uint64_t *u64)
1303 {
1304     int ret;
1305     VhostUserMsg msg = {
1306         .hdr.request = request,
1307         .hdr.flags = VHOST_USER_VERSION,
1308     };
1309 
1310     if (vhost_user_one_time_request(request) && dev->vq_index != 0) {
1311         return 0;
1312     }
1313 
1314     ret = vhost_user_write(dev, &msg, NULL, 0);
1315     if (ret < 0) {
1316         return ret;
1317     }
1318 
1319     ret = vhost_user_read(dev, &msg);
1320     if (ret < 0) {
1321         return ret;
1322     }
1323 
1324     if (msg.hdr.request != request) {
1325         error_report("Received unexpected msg type. Expected %d received %d",
1326                      request, msg.hdr.request);
1327         return -EPROTO;
1328     }
1329 
1330     if (msg.hdr.size != sizeof(msg.payload.u64)) {
1331         error_report("Received bad msg size.");
1332         return -EPROTO;
1333     }
1334 
1335     *u64 = msg.payload.u64;
1336 
1337     return 0;
1338 }
1339 
1340 static int vhost_user_get_features(struct vhost_dev *dev, uint64_t *features)
1341 {
1342     if (vhost_user_get_u64(dev, VHOST_USER_GET_FEATURES, features) < 0) {
1343         return -EPROTO;
1344     }
1345 
1346     return 0;
1347 }
1348 
1349 static int enforce_reply(struct vhost_dev *dev,
1350                          const VhostUserMsg *msg)
1351 {
1352     uint64_t dummy;
1353 
1354     if (msg->hdr.flags & VHOST_USER_NEED_REPLY_MASK) {
1355         return process_message_reply(dev, msg);
1356     }
1357 
1358    /*
1359     * We need to wait for a reply but the backend does not
1360     * support replies for the command we just sent.
1361     * Send VHOST_USER_GET_FEATURES which makes all backends
1362     * send a reply.
1363     */
1364     return vhost_user_get_features(dev, &dummy);
1365 }
1366 
1367 static int vhost_user_set_vring_addr(struct vhost_dev *dev,
1368                                      struct vhost_vring_addr *addr)
1369 {
1370     int ret;
1371     VhostUserMsg msg = {
1372         .hdr.request = VHOST_USER_SET_VRING_ADDR,
1373         .hdr.flags = VHOST_USER_VERSION,
1374         .payload.addr = *addr,
1375         .hdr.size = sizeof(msg.payload.addr),
1376     };
1377 
1378     bool reply_supported = virtio_has_feature(dev->protocol_features,
1379                                               VHOST_USER_PROTOCOL_F_REPLY_ACK);
1380 
1381     /*
1382      * wait for a reply if logging is enabled to make sure
1383      * backend is actually logging changes
1384      */
1385     bool wait_for_reply = addr->flags & (1 << VHOST_VRING_F_LOG);
1386 
1387     if (reply_supported && wait_for_reply) {
1388         msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
1389     }
1390 
1391     ret = vhost_user_write(dev, &msg, NULL, 0);
1392     if (ret < 0) {
1393         return ret;
1394     }
1395 
1396     if (wait_for_reply) {
1397         return enforce_reply(dev, &msg);
1398     }
1399 
1400     return 0;
1401 }
1402 
1403 static int vhost_user_set_u64(struct vhost_dev *dev, int request, uint64_t u64,
1404                               bool wait_for_reply)
1405 {
1406     VhostUserMsg msg = {
1407         .hdr.request = request,
1408         .hdr.flags = VHOST_USER_VERSION,
1409         .payload.u64 = u64,
1410         .hdr.size = sizeof(msg.payload.u64),
1411     };
1412     int ret;
1413 
1414     if (wait_for_reply) {
1415         bool reply_supported = virtio_has_feature(dev->protocol_features,
1416                                           VHOST_USER_PROTOCOL_F_REPLY_ACK);
1417         if (reply_supported) {
1418             msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
1419         }
1420     }
1421 
1422     ret = vhost_user_write(dev, &msg, NULL, 0);
1423     if (ret < 0) {
1424         return ret;
1425     }
1426 
1427     if (wait_for_reply) {
1428         return enforce_reply(dev, &msg);
1429     }
1430 
1431     return 0;
1432 }
1433 
1434 static int vhost_user_set_features(struct vhost_dev *dev,
1435                                    uint64_t features)
1436 {
1437     /*
1438      * wait for a reply if logging is enabled to make sure
1439      * backend is actually logging changes
1440      */
1441     bool log_enabled = features & (0x1ULL << VHOST_F_LOG_ALL);
1442 
1443     return vhost_user_set_u64(dev, VHOST_USER_SET_FEATURES, features,
1444                               log_enabled);
1445 }
1446 
1447 static int vhost_user_set_protocol_features(struct vhost_dev *dev,
1448                                             uint64_t features)
1449 {
1450     return vhost_user_set_u64(dev, VHOST_USER_SET_PROTOCOL_FEATURES, features,
1451                               false);
1452 }
1453 
1454 static int vhost_user_set_owner(struct vhost_dev *dev)
1455 {
1456     VhostUserMsg msg = {
1457         .hdr.request = VHOST_USER_SET_OWNER,
1458         .hdr.flags = VHOST_USER_VERSION,
1459     };
1460 
1461     return vhost_user_write(dev, &msg, NULL, 0);
1462 }
1463 
1464 static int vhost_user_get_max_memslots(struct vhost_dev *dev,
1465                                        uint64_t *max_memslots)
1466 {
1467     uint64_t backend_max_memslots;
1468     int err;
1469 
1470     err = vhost_user_get_u64(dev, VHOST_USER_GET_MAX_MEM_SLOTS,
1471                              &backend_max_memslots);
1472     if (err < 0) {
1473         return err;
1474     }
1475 
1476     *max_memslots = backend_max_memslots;
1477 
1478     return 0;
1479 }
1480 
1481 static int vhost_user_reset_device(struct vhost_dev *dev)
1482 {
1483     VhostUserMsg msg = {
1484         .hdr.flags = VHOST_USER_VERSION,
1485     };
1486 
1487     msg.hdr.request = virtio_has_feature(dev->protocol_features,
1488                                          VHOST_USER_PROTOCOL_F_RESET_DEVICE)
1489         ? VHOST_USER_RESET_DEVICE
1490         : VHOST_USER_RESET_OWNER;
1491 
1492     return vhost_user_write(dev, &msg, NULL, 0);
1493 }
1494 
1495 static int vhost_user_slave_handle_config_change(struct vhost_dev *dev)
1496 {
1497     if (!dev->config_ops || !dev->config_ops->vhost_dev_config_notifier) {
1498         return -ENOSYS;
1499     }
1500 
1501     return dev->config_ops->vhost_dev_config_notifier(dev);
1502 }
1503 
1504 static int vhost_user_slave_handle_vring_host_notifier(struct vhost_dev *dev,
1505                                                        VhostUserVringArea *area,
1506                                                        int fd)
1507 {
1508     int queue_idx = area->u64 & VHOST_USER_VRING_IDX_MASK;
1509     size_t page_size = qemu_real_host_page_size;
1510     struct vhost_user *u = dev->opaque;
1511     VhostUserState *user = u->user;
1512     VirtIODevice *vdev = dev->vdev;
1513     VhostUserHostNotifier *n;
1514     void *addr;
1515     char *name;
1516 
1517     if (!virtio_has_feature(dev->protocol_features,
1518                             VHOST_USER_PROTOCOL_F_HOST_NOTIFIER) ||
1519         vdev == NULL || queue_idx >= virtio_get_num_queues(vdev)) {
1520         return -EINVAL;
1521     }
1522 
1523     n = &user->notifier[queue_idx];
1524 
1525     if (n->addr) {
1526         virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, false);
1527         object_unparent(OBJECT(&n->mr));
1528         munmap(n->addr, page_size);
1529         n->addr = NULL;
1530     }
1531 
1532     if (area->u64 & VHOST_USER_VRING_NOFD_MASK) {
1533         return 0;
1534     }
1535 
1536     /* Sanity check. */
1537     if (area->size != page_size) {
1538         return -EINVAL;
1539     }
1540 
1541     addr = mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_SHARED,
1542                 fd, area->offset);
1543     if (addr == MAP_FAILED) {
1544         return -EFAULT;
1545     }
1546 
1547     name = g_strdup_printf("vhost-user/host-notifier@%p mmaps[%d]",
1548                            user, queue_idx);
1549     if (!n->mr.ram) /* Don't init again after suspend. */
1550         memory_region_init_ram_device_ptr(&n->mr, OBJECT(vdev), name,
1551                                           page_size, addr);
1552     g_free(name);
1553 
1554     if (virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, true)) {
1555         object_unparent(OBJECT(&n->mr));
1556         munmap(addr, page_size);
1557         return -ENXIO;
1558     }
1559 
1560     n->addr = addr;
1561     n->set = true;
1562 
1563     return 0;
1564 }
1565 
1566 static void close_slave_channel(struct vhost_user *u)
1567 {
1568     g_source_destroy(u->slave_src);
1569     g_source_unref(u->slave_src);
1570     u->slave_src = NULL;
1571     object_unref(OBJECT(u->slave_ioc));
1572     u->slave_ioc = NULL;
1573 }
1574 
1575 static gboolean slave_read(QIOChannel *ioc, GIOCondition condition,
1576                            gpointer opaque)
1577 {
1578     struct vhost_dev *dev = opaque;
1579     struct vhost_user *u = dev->opaque;
1580     VhostUserHeader hdr = { 0, };
1581     VhostUserPayload payload = { 0, };
1582     Error *local_err = NULL;
1583     gboolean rc = G_SOURCE_CONTINUE;
1584     int ret = 0;
1585     struct iovec iov;
1586     g_autofree int *fd = NULL;
1587     size_t fdsize = 0;
1588     int i;
1589 
1590     /* Read header */
1591     iov.iov_base = &hdr;
1592     iov.iov_len = VHOST_USER_HDR_SIZE;
1593 
1594     if (qio_channel_readv_full_all(ioc, &iov, 1, &fd, &fdsize, &local_err)) {
1595         error_report_err(local_err);
1596         goto err;
1597     }
1598 
1599     if (hdr.size > VHOST_USER_PAYLOAD_SIZE) {
1600         error_report("Failed to read msg header."
1601                 " Size %d exceeds the maximum %zu.", hdr.size,
1602                 VHOST_USER_PAYLOAD_SIZE);
1603         goto err;
1604     }
1605 
1606     /* Read payload */
1607     if (qio_channel_read_all(ioc, (char *) &payload, hdr.size, &local_err)) {
1608         error_report_err(local_err);
1609         goto err;
1610     }
1611 
1612     switch (hdr.request) {
1613     case VHOST_USER_SLAVE_IOTLB_MSG:
1614         ret = vhost_backend_handle_iotlb_msg(dev, &payload.iotlb);
1615         break;
1616     case VHOST_USER_SLAVE_CONFIG_CHANGE_MSG :
1617         ret = vhost_user_slave_handle_config_change(dev);
1618         break;
1619     case VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG:
1620         ret = vhost_user_slave_handle_vring_host_notifier(dev, &payload.area,
1621                                                           fd ? fd[0] : -1);
1622         break;
1623     default:
1624         error_report("Received unexpected msg type: %d.", hdr.request);
1625         ret = -EINVAL;
1626     }
1627 
1628     /*
1629      * REPLY_ACK feature handling. Other reply types has to be managed
1630      * directly in their request handlers.
1631      */
1632     if (hdr.flags & VHOST_USER_NEED_REPLY_MASK) {
1633         struct iovec iovec[2];
1634 
1635 
1636         hdr.flags &= ~VHOST_USER_NEED_REPLY_MASK;
1637         hdr.flags |= VHOST_USER_REPLY_MASK;
1638 
1639         payload.u64 = !!ret;
1640         hdr.size = sizeof(payload.u64);
1641 
1642         iovec[0].iov_base = &hdr;
1643         iovec[0].iov_len = VHOST_USER_HDR_SIZE;
1644         iovec[1].iov_base = &payload;
1645         iovec[1].iov_len = hdr.size;
1646 
1647         if (qio_channel_writev_all(ioc, iovec, ARRAY_SIZE(iovec), &local_err)) {
1648             error_report_err(local_err);
1649             goto err;
1650         }
1651     }
1652 
1653     goto fdcleanup;
1654 
1655 err:
1656     close_slave_channel(u);
1657     rc = G_SOURCE_REMOVE;
1658 
1659 fdcleanup:
1660     if (fd) {
1661         for (i = 0; i < fdsize; i++) {
1662             close(fd[i]);
1663         }
1664     }
1665     return rc;
1666 }
1667 
1668 static int vhost_setup_slave_channel(struct vhost_dev *dev)
1669 {
1670     VhostUserMsg msg = {
1671         .hdr.request = VHOST_USER_SET_SLAVE_REQ_FD,
1672         .hdr.flags = VHOST_USER_VERSION,
1673     };
1674     struct vhost_user *u = dev->opaque;
1675     int sv[2], ret = 0;
1676     bool reply_supported = virtio_has_feature(dev->protocol_features,
1677                                               VHOST_USER_PROTOCOL_F_REPLY_ACK);
1678     Error *local_err = NULL;
1679     QIOChannel *ioc;
1680 
1681     if (!virtio_has_feature(dev->protocol_features,
1682                             VHOST_USER_PROTOCOL_F_SLAVE_REQ)) {
1683         return 0;
1684     }
1685 
1686     if (socketpair(PF_UNIX, SOCK_STREAM, 0, sv) == -1) {
1687         int saved_errno = errno;
1688         error_report("socketpair() failed");
1689         return -saved_errno;
1690     }
1691 
1692     ioc = QIO_CHANNEL(qio_channel_socket_new_fd(sv[0], &local_err));
1693     if (!ioc) {
1694         error_report_err(local_err);
1695         return -ECONNREFUSED;
1696     }
1697     u->slave_ioc = ioc;
1698     slave_update_read_handler(dev, NULL);
1699 
1700     if (reply_supported) {
1701         msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
1702     }
1703 
1704     ret = vhost_user_write(dev, &msg, &sv[1], 1);
1705     if (ret) {
1706         goto out;
1707     }
1708 
1709     if (reply_supported) {
1710         ret = process_message_reply(dev, &msg);
1711     }
1712 
1713 out:
1714     close(sv[1]);
1715     if (ret) {
1716         close_slave_channel(u);
1717     }
1718 
1719     return ret;
1720 }
1721 
1722 #ifdef CONFIG_LINUX
1723 /*
1724  * Called back from the postcopy fault thread when a fault is received on our
1725  * ufd.
1726  * TODO: This is Linux specific
1727  */
1728 static int vhost_user_postcopy_fault_handler(struct PostCopyFD *pcfd,
1729                                              void *ufd)
1730 {
1731     struct vhost_dev *dev = pcfd->data;
1732     struct vhost_user *u = dev->opaque;
1733     struct uffd_msg *msg = ufd;
1734     uint64_t faultaddr = msg->arg.pagefault.address;
1735     RAMBlock *rb = NULL;
1736     uint64_t rb_offset;
1737     int i;
1738 
1739     trace_vhost_user_postcopy_fault_handler(pcfd->idstr, faultaddr,
1740                                             dev->mem->nregions);
1741     for (i = 0; i < MIN(dev->mem->nregions, u->region_rb_len); i++) {
1742         trace_vhost_user_postcopy_fault_handler_loop(i,
1743                 u->postcopy_client_bases[i], dev->mem->regions[i].memory_size);
1744         if (faultaddr >= u->postcopy_client_bases[i]) {
1745             /* Ofset of the fault address in the vhost region */
1746             uint64_t region_offset = faultaddr - u->postcopy_client_bases[i];
1747             if (region_offset < dev->mem->regions[i].memory_size) {
1748                 rb_offset = region_offset + u->region_rb_offset[i];
1749                 trace_vhost_user_postcopy_fault_handler_found(i,
1750                         region_offset, rb_offset);
1751                 rb = u->region_rb[i];
1752                 return postcopy_request_shared_page(pcfd, rb, faultaddr,
1753                                                     rb_offset);
1754             }
1755         }
1756     }
1757     error_report("%s: Failed to find region for fault %" PRIx64,
1758                  __func__, faultaddr);
1759     return -1;
1760 }
1761 
1762 static int vhost_user_postcopy_waker(struct PostCopyFD *pcfd, RAMBlock *rb,
1763                                      uint64_t offset)
1764 {
1765     struct vhost_dev *dev = pcfd->data;
1766     struct vhost_user *u = dev->opaque;
1767     int i;
1768 
1769     trace_vhost_user_postcopy_waker(qemu_ram_get_idstr(rb), offset);
1770 
1771     if (!u) {
1772         return 0;
1773     }
1774     /* Translate the offset into an address in the clients address space */
1775     for (i = 0; i < MIN(dev->mem->nregions, u->region_rb_len); i++) {
1776         if (u->region_rb[i] == rb &&
1777             offset >= u->region_rb_offset[i] &&
1778             offset < (u->region_rb_offset[i] +
1779                       dev->mem->regions[i].memory_size)) {
1780             uint64_t client_addr = (offset - u->region_rb_offset[i]) +
1781                                    u->postcopy_client_bases[i];
1782             trace_vhost_user_postcopy_waker_found(client_addr);
1783             return postcopy_wake_shared(pcfd, client_addr, rb);
1784         }
1785     }
1786 
1787     trace_vhost_user_postcopy_waker_nomatch(qemu_ram_get_idstr(rb), offset);
1788     return 0;
1789 }
1790 #endif
1791 
1792 /*
1793  * Called at the start of an inbound postcopy on reception of the
1794  * 'advise' command.
1795  */
1796 static int vhost_user_postcopy_advise(struct vhost_dev *dev, Error **errp)
1797 {
1798 #ifdef CONFIG_LINUX
1799     struct vhost_user *u = dev->opaque;
1800     CharBackend *chr = u->user->chr;
1801     int ufd;
1802     int ret;
1803     VhostUserMsg msg = {
1804         .hdr.request = VHOST_USER_POSTCOPY_ADVISE,
1805         .hdr.flags = VHOST_USER_VERSION,
1806     };
1807 
1808     ret = vhost_user_write(dev, &msg, NULL, 0);
1809     if (ret < 0) {
1810         error_setg(errp, "Failed to send postcopy_advise to vhost");
1811         return ret;
1812     }
1813 
1814     ret = vhost_user_read(dev, &msg);
1815     if (ret < 0) {
1816         error_setg(errp, "Failed to get postcopy_advise reply from vhost");
1817         return ret;
1818     }
1819 
1820     if (msg.hdr.request != VHOST_USER_POSTCOPY_ADVISE) {
1821         error_setg(errp, "Unexpected msg type. Expected %d received %d",
1822                      VHOST_USER_POSTCOPY_ADVISE, msg.hdr.request);
1823         return -EPROTO;
1824     }
1825 
1826     if (msg.hdr.size) {
1827         error_setg(errp, "Received bad msg size.");
1828         return -EPROTO;
1829     }
1830     ufd = qemu_chr_fe_get_msgfd(chr);
1831     if (ufd < 0) {
1832         error_setg(errp, "%s: Failed to get ufd", __func__);
1833         return -EIO;
1834     }
1835     qemu_set_nonblock(ufd);
1836 
1837     /* register ufd with userfault thread */
1838     u->postcopy_fd.fd = ufd;
1839     u->postcopy_fd.data = dev;
1840     u->postcopy_fd.handler = vhost_user_postcopy_fault_handler;
1841     u->postcopy_fd.waker = vhost_user_postcopy_waker;
1842     u->postcopy_fd.idstr = "vhost-user"; /* Need to find unique name */
1843     postcopy_register_shared_ufd(&u->postcopy_fd);
1844     return 0;
1845 #else
1846     error_setg(errp, "Postcopy not supported on non-Linux systems");
1847     return -ENOSYS;
1848 #endif
1849 }
1850 
1851 /*
1852  * Called at the switch to postcopy on reception of the 'listen' command.
1853  */
1854 static int vhost_user_postcopy_listen(struct vhost_dev *dev, Error **errp)
1855 {
1856     struct vhost_user *u = dev->opaque;
1857     int ret;
1858     VhostUserMsg msg = {
1859         .hdr.request = VHOST_USER_POSTCOPY_LISTEN,
1860         .hdr.flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK,
1861     };
1862     u->postcopy_listen = true;
1863 
1864     trace_vhost_user_postcopy_listen();
1865 
1866     ret = vhost_user_write(dev, &msg, NULL, 0);
1867     if (ret < 0) {
1868         error_setg(errp, "Failed to send postcopy_listen to vhost");
1869         return ret;
1870     }
1871 
1872     ret = process_message_reply(dev, &msg);
1873     if (ret) {
1874         error_setg(errp, "Failed to receive reply to postcopy_listen");
1875         return ret;
1876     }
1877 
1878     return 0;
1879 }
1880 
1881 /*
1882  * Called at the end of postcopy
1883  */
1884 static int vhost_user_postcopy_end(struct vhost_dev *dev, Error **errp)
1885 {
1886     VhostUserMsg msg = {
1887         .hdr.request = VHOST_USER_POSTCOPY_END,
1888         .hdr.flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK,
1889     };
1890     int ret;
1891     struct vhost_user *u = dev->opaque;
1892 
1893     trace_vhost_user_postcopy_end_entry();
1894 
1895     ret = vhost_user_write(dev, &msg, NULL, 0);
1896     if (ret < 0) {
1897         error_setg(errp, "Failed to send postcopy_end to vhost");
1898         return ret;
1899     }
1900 
1901     ret = process_message_reply(dev, &msg);
1902     if (ret) {
1903         error_setg(errp, "Failed to receive reply to postcopy_end");
1904         return ret;
1905     }
1906     postcopy_unregister_shared_ufd(&u->postcopy_fd);
1907     close(u->postcopy_fd.fd);
1908     u->postcopy_fd.handler = NULL;
1909 
1910     trace_vhost_user_postcopy_end_exit();
1911 
1912     return 0;
1913 }
1914 
1915 static int vhost_user_postcopy_notifier(NotifierWithReturn *notifier,
1916                                         void *opaque)
1917 {
1918     struct PostcopyNotifyData *pnd = opaque;
1919     struct vhost_user *u = container_of(notifier, struct vhost_user,
1920                                          postcopy_notifier);
1921     struct vhost_dev *dev = u->dev;
1922 
1923     switch (pnd->reason) {
1924     case POSTCOPY_NOTIFY_PROBE:
1925         if (!virtio_has_feature(dev->protocol_features,
1926                                 VHOST_USER_PROTOCOL_F_PAGEFAULT)) {
1927             /* TODO: Get the device name into this error somehow */
1928             error_setg(pnd->errp,
1929                        "vhost-user backend not capable of postcopy");
1930             return -ENOENT;
1931         }
1932         break;
1933 
1934     case POSTCOPY_NOTIFY_INBOUND_ADVISE:
1935         return vhost_user_postcopy_advise(dev, pnd->errp);
1936 
1937     case POSTCOPY_NOTIFY_INBOUND_LISTEN:
1938         return vhost_user_postcopy_listen(dev, pnd->errp);
1939 
1940     case POSTCOPY_NOTIFY_INBOUND_END:
1941         return vhost_user_postcopy_end(dev, pnd->errp);
1942 
1943     default:
1944         /* We ignore notifications we don't know */
1945         break;
1946     }
1947 
1948     return 0;
1949 }
1950 
1951 static int vhost_user_backend_init(struct vhost_dev *dev, void *opaque,
1952                                    Error **errp)
1953 {
1954     uint64_t features, protocol_features, ram_slots;
1955     struct vhost_user *u;
1956     int err;
1957 
1958     assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
1959 
1960     u = g_new0(struct vhost_user, 1);
1961     u->user = opaque;
1962     u->dev = dev;
1963     dev->opaque = u;
1964 
1965     err = vhost_user_get_features(dev, &features);
1966     if (err < 0) {
1967         error_setg_errno(errp, -err, "vhost_backend_init failed");
1968         return err;
1969     }
1970 
1971     if (virtio_has_feature(features, VHOST_USER_F_PROTOCOL_FEATURES)) {
1972         dev->backend_features |= 1ULL << VHOST_USER_F_PROTOCOL_FEATURES;
1973 
1974         err = vhost_user_get_u64(dev, VHOST_USER_GET_PROTOCOL_FEATURES,
1975                                  &protocol_features);
1976         if (err < 0) {
1977             error_setg_errno(errp, EPROTO, "vhost_backend_init failed");
1978             return -EPROTO;
1979         }
1980 
1981         dev->protocol_features =
1982             protocol_features & VHOST_USER_PROTOCOL_FEATURE_MASK;
1983 
1984         if (!dev->config_ops || !dev->config_ops->vhost_dev_config_notifier) {
1985             /* Don't acknowledge CONFIG feature if device doesn't support it */
1986             dev->protocol_features &= ~(1ULL << VHOST_USER_PROTOCOL_F_CONFIG);
1987         } else if (!(protocol_features &
1988                     (1ULL << VHOST_USER_PROTOCOL_F_CONFIG))) {
1989             error_setg(errp, "Device expects VHOST_USER_PROTOCOL_F_CONFIG "
1990                        "but backend does not support it.");
1991             return -EINVAL;
1992         }
1993 
1994         err = vhost_user_set_protocol_features(dev, dev->protocol_features);
1995         if (err < 0) {
1996             error_setg_errno(errp, EPROTO, "vhost_backend_init failed");
1997             return -EPROTO;
1998         }
1999 
2000         /* query the max queues we support if backend supports Multiple Queue */
2001         if (dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_MQ)) {
2002             err = vhost_user_get_u64(dev, VHOST_USER_GET_QUEUE_NUM,
2003                                      &dev->max_queues);
2004             if (err < 0) {
2005                 error_setg_errno(errp, EPROTO, "vhost_backend_init failed");
2006                 return -EPROTO;
2007             }
2008         } else {
2009             dev->max_queues = 1;
2010         }
2011 
2012         if (dev->num_queues && dev->max_queues < dev->num_queues) {
2013             error_setg(errp, "The maximum number of queues supported by the "
2014                        "backend is %" PRIu64, dev->max_queues);
2015             return -EINVAL;
2016         }
2017 
2018         if (virtio_has_feature(features, VIRTIO_F_IOMMU_PLATFORM) &&
2019                 !(virtio_has_feature(dev->protocol_features,
2020                     VHOST_USER_PROTOCOL_F_SLAVE_REQ) &&
2021                  virtio_has_feature(dev->protocol_features,
2022                     VHOST_USER_PROTOCOL_F_REPLY_ACK))) {
2023             error_setg(errp, "IOMMU support requires reply-ack and "
2024                        "slave-req protocol features.");
2025             return -EINVAL;
2026         }
2027 
2028         /* get max memory regions if backend supports configurable RAM slots */
2029         if (!virtio_has_feature(dev->protocol_features,
2030                                 VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS)) {
2031             u->user->memory_slots = VHOST_MEMORY_BASELINE_NREGIONS;
2032         } else {
2033             err = vhost_user_get_max_memslots(dev, &ram_slots);
2034             if (err < 0) {
2035                 error_setg_errno(errp, EPROTO, "vhost_backend_init failed");
2036                 return -EPROTO;
2037             }
2038 
2039             if (ram_slots < u->user->memory_slots) {
2040                 error_setg(errp, "The backend specified a max ram slots limit "
2041                            "of %" PRIu64", when the prior validated limit was "
2042                            "%d. This limit should never decrease.", ram_slots,
2043                            u->user->memory_slots);
2044                 return -EINVAL;
2045             }
2046 
2047             u->user->memory_slots = MIN(ram_slots, VHOST_USER_MAX_RAM_SLOTS);
2048         }
2049     }
2050 
2051     if (dev->migration_blocker == NULL &&
2052         !virtio_has_feature(dev->protocol_features,
2053                             VHOST_USER_PROTOCOL_F_LOG_SHMFD)) {
2054         error_setg(&dev->migration_blocker,
2055                    "Migration disabled: vhost-user backend lacks "
2056                    "VHOST_USER_PROTOCOL_F_LOG_SHMFD feature.");
2057     }
2058 
2059     if (dev->vq_index == 0) {
2060         err = vhost_setup_slave_channel(dev);
2061         if (err < 0) {
2062             error_setg_errno(errp, EPROTO, "vhost_backend_init failed");
2063             return -EPROTO;
2064         }
2065     }
2066 
2067     u->postcopy_notifier.notify = vhost_user_postcopy_notifier;
2068     postcopy_add_notifier(&u->postcopy_notifier);
2069 
2070     return 0;
2071 }
2072 
2073 static int vhost_user_backend_cleanup(struct vhost_dev *dev)
2074 {
2075     struct vhost_user *u;
2076 
2077     assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
2078 
2079     u = dev->opaque;
2080     if (u->postcopy_notifier.notify) {
2081         postcopy_remove_notifier(&u->postcopy_notifier);
2082         u->postcopy_notifier.notify = NULL;
2083     }
2084     u->postcopy_listen = false;
2085     if (u->postcopy_fd.handler) {
2086         postcopy_unregister_shared_ufd(&u->postcopy_fd);
2087         close(u->postcopy_fd.fd);
2088         u->postcopy_fd.handler = NULL;
2089     }
2090     if (u->slave_ioc) {
2091         close_slave_channel(u);
2092     }
2093     g_free(u->region_rb);
2094     u->region_rb = NULL;
2095     g_free(u->region_rb_offset);
2096     u->region_rb_offset = NULL;
2097     u->region_rb_len = 0;
2098     g_free(u);
2099     dev->opaque = 0;
2100 
2101     return 0;
2102 }
2103 
2104 static int vhost_user_get_vq_index(struct vhost_dev *dev, int idx)
2105 {
2106     assert(idx >= dev->vq_index && idx < dev->vq_index + dev->nvqs);
2107 
2108     return idx;
2109 }
2110 
2111 static int vhost_user_memslots_limit(struct vhost_dev *dev)
2112 {
2113     struct vhost_user *u = dev->opaque;
2114 
2115     return u->user->memory_slots;
2116 }
2117 
2118 static bool vhost_user_requires_shm_log(struct vhost_dev *dev)
2119 {
2120     assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
2121 
2122     return virtio_has_feature(dev->protocol_features,
2123                               VHOST_USER_PROTOCOL_F_LOG_SHMFD);
2124 }
2125 
2126 static int vhost_user_migration_done(struct vhost_dev *dev, char* mac_addr)
2127 {
2128     VhostUserMsg msg = { };
2129 
2130     assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
2131 
2132     /* If guest supports GUEST_ANNOUNCE do nothing */
2133     if (virtio_has_feature(dev->acked_features, VIRTIO_NET_F_GUEST_ANNOUNCE)) {
2134         return 0;
2135     }
2136 
2137     /* if backend supports VHOST_USER_PROTOCOL_F_RARP ask it to send the RARP */
2138     if (virtio_has_feature(dev->protocol_features,
2139                            VHOST_USER_PROTOCOL_F_RARP)) {
2140         msg.hdr.request = VHOST_USER_SEND_RARP;
2141         msg.hdr.flags = VHOST_USER_VERSION;
2142         memcpy((char *)&msg.payload.u64, mac_addr, 6);
2143         msg.hdr.size = sizeof(msg.payload.u64);
2144 
2145         return vhost_user_write(dev, &msg, NULL, 0);
2146     }
2147     return -ENOTSUP;
2148 }
2149 
2150 static bool vhost_user_can_merge(struct vhost_dev *dev,
2151                                  uint64_t start1, uint64_t size1,
2152                                  uint64_t start2, uint64_t size2)
2153 {
2154     ram_addr_t offset;
2155     int mfd, rfd;
2156 
2157     (void)vhost_user_get_mr_data(start1, &offset, &mfd);
2158     (void)vhost_user_get_mr_data(start2, &offset, &rfd);
2159 
2160     return mfd == rfd;
2161 }
2162 
2163 static int vhost_user_net_set_mtu(struct vhost_dev *dev, uint16_t mtu)
2164 {
2165     VhostUserMsg msg;
2166     bool reply_supported = virtio_has_feature(dev->protocol_features,
2167                                               VHOST_USER_PROTOCOL_F_REPLY_ACK);
2168     int ret;
2169 
2170     if (!(dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_NET_MTU))) {
2171         return 0;
2172     }
2173 
2174     msg.hdr.request = VHOST_USER_NET_SET_MTU;
2175     msg.payload.u64 = mtu;
2176     msg.hdr.size = sizeof(msg.payload.u64);
2177     msg.hdr.flags = VHOST_USER_VERSION;
2178     if (reply_supported) {
2179         msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
2180     }
2181 
2182     ret = vhost_user_write(dev, &msg, NULL, 0);
2183     if (ret < 0) {
2184         return ret;
2185     }
2186 
2187     /* If reply_ack supported, slave has to ack specified MTU is valid */
2188     if (reply_supported) {
2189         return process_message_reply(dev, &msg);
2190     }
2191 
2192     return 0;
2193 }
2194 
2195 static int vhost_user_send_device_iotlb_msg(struct vhost_dev *dev,
2196                                             struct vhost_iotlb_msg *imsg)
2197 {
2198     int ret;
2199     VhostUserMsg msg = {
2200         .hdr.request = VHOST_USER_IOTLB_MSG,
2201         .hdr.size = sizeof(msg.payload.iotlb),
2202         .hdr.flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK,
2203         .payload.iotlb = *imsg,
2204     };
2205 
2206     ret = vhost_user_write(dev, &msg, NULL, 0);
2207     if (ret < 0) {
2208         return ret;
2209     }
2210 
2211     return process_message_reply(dev, &msg);
2212 }
2213 
2214 
2215 static void vhost_user_set_iotlb_callback(struct vhost_dev *dev, int enabled)
2216 {
2217     /* No-op as the receive channel is not dedicated to IOTLB messages. */
2218 }
2219 
2220 static int vhost_user_get_config(struct vhost_dev *dev, uint8_t *config,
2221                                  uint32_t config_len, Error **errp)
2222 {
2223     int ret;
2224     VhostUserMsg msg = {
2225         .hdr.request = VHOST_USER_GET_CONFIG,
2226         .hdr.flags = VHOST_USER_VERSION,
2227         .hdr.size = VHOST_USER_CONFIG_HDR_SIZE + config_len,
2228     };
2229 
2230     if (!virtio_has_feature(dev->protocol_features,
2231                 VHOST_USER_PROTOCOL_F_CONFIG)) {
2232         error_setg(errp, "VHOST_USER_PROTOCOL_F_CONFIG not supported");
2233         return -EINVAL;
2234     }
2235 
2236     assert(config_len <= VHOST_USER_MAX_CONFIG_SIZE);
2237 
2238     msg.payload.config.offset = 0;
2239     msg.payload.config.size = config_len;
2240     ret = vhost_user_write(dev, &msg, NULL, 0);
2241     if (ret < 0) {
2242         error_setg_errno(errp, -ret, "vhost_get_config failed");
2243         return ret;
2244     }
2245 
2246     ret = vhost_user_read(dev, &msg);
2247     if (ret < 0) {
2248         error_setg_errno(errp, -ret, "vhost_get_config failed");
2249         return ret;
2250     }
2251 
2252     if (msg.hdr.request != VHOST_USER_GET_CONFIG) {
2253         error_setg(errp,
2254                    "Received unexpected msg type. Expected %d received %d",
2255                    VHOST_USER_GET_CONFIG, msg.hdr.request);
2256         return -EPROTO;
2257     }
2258 
2259     if (msg.hdr.size != VHOST_USER_CONFIG_HDR_SIZE + config_len) {
2260         error_setg(errp, "Received bad msg size.");
2261         return -EPROTO;
2262     }
2263 
2264     memcpy(config, msg.payload.config.region, config_len);
2265 
2266     return 0;
2267 }
2268 
2269 static int vhost_user_set_config(struct vhost_dev *dev, const uint8_t *data,
2270                                  uint32_t offset, uint32_t size, uint32_t flags)
2271 {
2272     int ret;
2273     uint8_t *p;
2274     bool reply_supported = virtio_has_feature(dev->protocol_features,
2275                                               VHOST_USER_PROTOCOL_F_REPLY_ACK);
2276 
2277     VhostUserMsg msg = {
2278         .hdr.request = VHOST_USER_SET_CONFIG,
2279         .hdr.flags = VHOST_USER_VERSION,
2280         .hdr.size = VHOST_USER_CONFIG_HDR_SIZE + size,
2281     };
2282 
2283     if (!virtio_has_feature(dev->protocol_features,
2284                 VHOST_USER_PROTOCOL_F_CONFIG)) {
2285         return -ENOTSUP;
2286     }
2287 
2288     if (reply_supported) {
2289         msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
2290     }
2291 
2292     if (size > VHOST_USER_MAX_CONFIG_SIZE) {
2293         return -EINVAL;
2294     }
2295 
2296     msg.payload.config.offset = offset,
2297     msg.payload.config.size = size,
2298     msg.payload.config.flags = flags,
2299     p = msg.payload.config.region;
2300     memcpy(p, data, size);
2301 
2302     ret = vhost_user_write(dev, &msg, NULL, 0);
2303     if (ret < 0) {
2304         return ret;
2305     }
2306 
2307     if (reply_supported) {
2308         return process_message_reply(dev, &msg);
2309     }
2310 
2311     return 0;
2312 }
2313 
2314 static int vhost_user_crypto_create_session(struct vhost_dev *dev,
2315                                             void *session_info,
2316                                             uint64_t *session_id)
2317 {
2318     int ret;
2319     bool crypto_session = virtio_has_feature(dev->protocol_features,
2320                                        VHOST_USER_PROTOCOL_F_CRYPTO_SESSION);
2321     CryptoDevBackendSymSessionInfo *sess_info = session_info;
2322     VhostUserMsg msg = {
2323         .hdr.request = VHOST_USER_CREATE_CRYPTO_SESSION,
2324         .hdr.flags = VHOST_USER_VERSION,
2325         .hdr.size = sizeof(msg.payload.session),
2326     };
2327 
2328     assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
2329 
2330     if (!crypto_session) {
2331         error_report("vhost-user trying to send unhandled ioctl");
2332         return -ENOTSUP;
2333     }
2334 
2335     memcpy(&msg.payload.session.session_setup_data, sess_info,
2336               sizeof(CryptoDevBackendSymSessionInfo));
2337     if (sess_info->key_len) {
2338         memcpy(&msg.payload.session.key, sess_info->cipher_key,
2339                sess_info->key_len);
2340     }
2341     if (sess_info->auth_key_len > 0) {
2342         memcpy(&msg.payload.session.auth_key, sess_info->auth_key,
2343                sess_info->auth_key_len);
2344     }
2345     ret = vhost_user_write(dev, &msg, NULL, 0);
2346     if (ret < 0) {
2347         error_report("vhost_user_write() return %d, create session failed",
2348                      ret);
2349         return ret;
2350     }
2351 
2352     ret = vhost_user_read(dev, &msg);
2353     if (ret < 0) {
2354         error_report("vhost_user_read() return %d, create session failed",
2355                      ret);
2356         return ret;
2357     }
2358 
2359     if (msg.hdr.request != VHOST_USER_CREATE_CRYPTO_SESSION) {
2360         error_report("Received unexpected msg type. Expected %d received %d",
2361                      VHOST_USER_CREATE_CRYPTO_SESSION, msg.hdr.request);
2362         return -EPROTO;
2363     }
2364 
2365     if (msg.hdr.size != sizeof(msg.payload.session)) {
2366         error_report("Received bad msg size.");
2367         return -EPROTO;
2368     }
2369 
2370     if (msg.payload.session.session_id < 0) {
2371         error_report("Bad session id: %" PRId64 "",
2372                               msg.payload.session.session_id);
2373         return -EINVAL;
2374     }
2375     *session_id = msg.payload.session.session_id;
2376 
2377     return 0;
2378 }
2379 
2380 static int
2381 vhost_user_crypto_close_session(struct vhost_dev *dev, uint64_t session_id)
2382 {
2383     int ret;
2384     bool crypto_session = virtio_has_feature(dev->protocol_features,
2385                                        VHOST_USER_PROTOCOL_F_CRYPTO_SESSION);
2386     VhostUserMsg msg = {
2387         .hdr.request = VHOST_USER_CLOSE_CRYPTO_SESSION,
2388         .hdr.flags = VHOST_USER_VERSION,
2389         .hdr.size = sizeof(msg.payload.u64),
2390     };
2391     msg.payload.u64 = session_id;
2392 
2393     if (!crypto_session) {
2394         error_report("vhost-user trying to send unhandled ioctl");
2395         return -ENOTSUP;
2396     }
2397 
2398     ret = vhost_user_write(dev, &msg, NULL, 0);
2399     if (ret < 0) {
2400         error_report("vhost_user_write() return %d, close session failed",
2401                      ret);
2402         return ret;
2403     }
2404 
2405     return 0;
2406 }
2407 
2408 static bool vhost_user_mem_section_filter(struct vhost_dev *dev,
2409                                           MemoryRegionSection *section)
2410 {
2411     bool result;
2412 
2413     result = memory_region_get_fd(section->mr) >= 0;
2414 
2415     return result;
2416 }
2417 
2418 static int vhost_user_get_inflight_fd(struct vhost_dev *dev,
2419                                       uint16_t queue_size,
2420                                       struct vhost_inflight *inflight)
2421 {
2422     void *addr;
2423     int fd;
2424     int ret;
2425     struct vhost_user *u = dev->opaque;
2426     CharBackend *chr = u->user->chr;
2427     VhostUserMsg msg = {
2428         .hdr.request = VHOST_USER_GET_INFLIGHT_FD,
2429         .hdr.flags = VHOST_USER_VERSION,
2430         .payload.inflight.num_queues = dev->nvqs,
2431         .payload.inflight.queue_size = queue_size,
2432         .hdr.size = sizeof(msg.payload.inflight),
2433     };
2434 
2435     if (!virtio_has_feature(dev->protocol_features,
2436                             VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) {
2437         return 0;
2438     }
2439 
2440     ret = vhost_user_write(dev, &msg, NULL, 0);
2441     if (ret < 0) {
2442         return ret;
2443     }
2444 
2445     ret = vhost_user_read(dev, &msg);
2446     if (ret < 0) {
2447         return ret;
2448     }
2449 
2450     if (msg.hdr.request != VHOST_USER_GET_INFLIGHT_FD) {
2451         error_report("Received unexpected msg type. "
2452                      "Expected %d received %d",
2453                      VHOST_USER_GET_INFLIGHT_FD, msg.hdr.request);
2454         return -EPROTO;
2455     }
2456 
2457     if (msg.hdr.size != sizeof(msg.payload.inflight)) {
2458         error_report("Received bad msg size.");
2459         return -EPROTO;
2460     }
2461 
2462     if (!msg.payload.inflight.mmap_size) {
2463         return 0;
2464     }
2465 
2466     fd = qemu_chr_fe_get_msgfd(chr);
2467     if (fd < 0) {
2468         error_report("Failed to get mem fd");
2469         return -EIO;
2470     }
2471 
2472     addr = mmap(0, msg.payload.inflight.mmap_size, PROT_READ | PROT_WRITE,
2473                 MAP_SHARED, fd, msg.payload.inflight.mmap_offset);
2474 
2475     if (addr == MAP_FAILED) {
2476         error_report("Failed to mmap mem fd");
2477         close(fd);
2478         return -EFAULT;
2479     }
2480 
2481     inflight->addr = addr;
2482     inflight->fd = fd;
2483     inflight->size = msg.payload.inflight.mmap_size;
2484     inflight->offset = msg.payload.inflight.mmap_offset;
2485     inflight->queue_size = queue_size;
2486 
2487     return 0;
2488 }
2489 
2490 static int vhost_user_set_inflight_fd(struct vhost_dev *dev,
2491                                       struct vhost_inflight *inflight)
2492 {
2493     VhostUserMsg msg = {
2494         .hdr.request = VHOST_USER_SET_INFLIGHT_FD,
2495         .hdr.flags = VHOST_USER_VERSION,
2496         .payload.inflight.mmap_size = inflight->size,
2497         .payload.inflight.mmap_offset = inflight->offset,
2498         .payload.inflight.num_queues = dev->nvqs,
2499         .payload.inflight.queue_size = inflight->queue_size,
2500         .hdr.size = sizeof(msg.payload.inflight),
2501     };
2502 
2503     if (!virtio_has_feature(dev->protocol_features,
2504                             VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) {
2505         return 0;
2506     }
2507 
2508     return vhost_user_write(dev, &msg, &inflight->fd, 1);
2509 }
2510 
2511 bool vhost_user_init(VhostUserState *user, CharBackend *chr, Error **errp)
2512 {
2513     if (user->chr) {
2514         error_setg(errp, "Cannot initialize vhost-user state");
2515         return false;
2516     }
2517     user->chr = chr;
2518     user->memory_slots = 0;
2519     return true;
2520 }
2521 
2522 void vhost_user_cleanup(VhostUserState *user)
2523 {
2524     int i;
2525 
2526     if (!user->chr) {
2527         return;
2528     }
2529     memory_region_transaction_begin();
2530     for (i = 0; i < VIRTIO_QUEUE_MAX; i++) {
2531         if (user->notifier[i].addr) {
2532             object_unparent(OBJECT(&user->notifier[i].mr));
2533             munmap(user->notifier[i].addr, qemu_real_host_page_size);
2534             user->notifier[i].addr = NULL;
2535         }
2536     }
2537     memory_region_transaction_commit();
2538     user->chr = NULL;
2539 }
2540 
2541 const VhostOps user_ops = {
2542         .backend_type = VHOST_BACKEND_TYPE_USER,
2543         .vhost_backend_init = vhost_user_backend_init,
2544         .vhost_backend_cleanup = vhost_user_backend_cleanup,
2545         .vhost_backend_memslots_limit = vhost_user_memslots_limit,
2546         .vhost_set_log_base = vhost_user_set_log_base,
2547         .vhost_set_mem_table = vhost_user_set_mem_table,
2548         .vhost_set_vring_addr = vhost_user_set_vring_addr,
2549         .vhost_set_vring_endian = vhost_user_set_vring_endian,
2550         .vhost_set_vring_num = vhost_user_set_vring_num,
2551         .vhost_set_vring_base = vhost_user_set_vring_base,
2552         .vhost_get_vring_base = vhost_user_get_vring_base,
2553         .vhost_set_vring_kick = vhost_user_set_vring_kick,
2554         .vhost_set_vring_call = vhost_user_set_vring_call,
2555         .vhost_set_features = vhost_user_set_features,
2556         .vhost_get_features = vhost_user_get_features,
2557         .vhost_set_owner = vhost_user_set_owner,
2558         .vhost_reset_device = vhost_user_reset_device,
2559         .vhost_get_vq_index = vhost_user_get_vq_index,
2560         .vhost_set_vring_enable = vhost_user_set_vring_enable,
2561         .vhost_requires_shm_log = vhost_user_requires_shm_log,
2562         .vhost_migration_done = vhost_user_migration_done,
2563         .vhost_backend_can_merge = vhost_user_can_merge,
2564         .vhost_net_set_mtu = vhost_user_net_set_mtu,
2565         .vhost_set_iotlb_callback = vhost_user_set_iotlb_callback,
2566         .vhost_send_device_iotlb_msg = vhost_user_send_device_iotlb_msg,
2567         .vhost_get_config = vhost_user_get_config,
2568         .vhost_set_config = vhost_user_set_config,
2569         .vhost_crypto_create_session = vhost_user_crypto_create_session,
2570         .vhost_crypto_close_session = vhost_user_crypto_close_session,
2571         .vhost_backend_mem_section_filter = vhost_user_mem_section_filter,
2572         .vhost_get_inflight_fd = vhost_user_get_inflight_fd,
2573         .vhost_set_inflight_fd = vhost_user_set_inflight_fd,
2574 };
2575