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/virtio-dmabuf.h"
14 #include "hw/virtio/vhost.h"
15 #include "hw/virtio/virtio-crypto.h"
16 #include "hw/virtio/vhost-user.h"
17 #include "hw/virtio/vhost-backend.h"
18 #include "hw/virtio/virtio.h"
19 #include "hw/virtio/virtio-net.h"
20 #include "chardev/char-fe.h"
21 #include "io/channel-socket.h"
22 #include "sysemu/kvm.h"
23 #include "qemu/error-report.h"
24 #include "qemu/main-loop.h"
25 #include "qemu/uuid.h"
26 #include "qemu/sockets.h"
27 #include "sysemu/runstate.h"
28 #include "sysemu/cryptodev.h"
29 #include "migration/postcopy-ram.h"
30 #include "trace.h"
31 #include "exec/ramblock.h"
32
33 #include <sys/ioctl.h>
34 #include <sys/socket.h>
35 #include <sys/un.h>
36
37 #include "standard-headers/linux/vhost_types.h"
38
39 #ifdef CONFIG_LINUX
40 #include <linux/userfaultfd.h>
41 #endif
42
43 #define VHOST_MEMORY_BASELINE_NREGIONS 8
44 #define VHOST_USER_F_PROTOCOL_FEATURES 30
45 #define VHOST_USER_BACKEND_MAX_FDS 8
46
47 #if defined(TARGET_PPC) || defined(TARGET_PPC64)
48 #include "hw/ppc/spapr.h"
49 #define VHOST_USER_MAX_RAM_SLOTS SPAPR_MAX_RAM_SLOTS
50
51 #else
52 #define VHOST_USER_MAX_RAM_SLOTS 512
53 #endif
54
55 /*
56 * Maximum size of virtio device config space
57 */
58 #define VHOST_USER_MAX_CONFIG_SIZE 256
59
60 #define VHOST_USER_PROTOCOL_FEATURE_MASK ((1 << VHOST_USER_PROTOCOL_F_MAX) - 1)
61
62 typedef enum VhostUserRequest {
63 VHOST_USER_NONE = 0,
64 VHOST_USER_GET_FEATURES = 1,
65 VHOST_USER_SET_FEATURES = 2,
66 VHOST_USER_SET_OWNER = 3,
67 VHOST_USER_RESET_OWNER = 4,
68 VHOST_USER_SET_MEM_TABLE = 5,
69 VHOST_USER_SET_LOG_BASE = 6,
70 VHOST_USER_SET_LOG_FD = 7,
71 VHOST_USER_SET_VRING_NUM = 8,
72 VHOST_USER_SET_VRING_ADDR = 9,
73 VHOST_USER_SET_VRING_BASE = 10,
74 VHOST_USER_GET_VRING_BASE = 11,
75 VHOST_USER_SET_VRING_KICK = 12,
76 VHOST_USER_SET_VRING_CALL = 13,
77 VHOST_USER_SET_VRING_ERR = 14,
78 VHOST_USER_GET_PROTOCOL_FEATURES = 15,
79 VHOST_USER_SET_PROTOCOL_FEATURES = 16,
80 VHOST_USER_GET_QUEUE_NUM = 17,
81 VHOST_USER_SET_VRING_ENABLE = 18,
82 VHOST_USER_SEND_RARP = 19,
83 VHOST_USER_NET_SET_MTU = 20,
84 VHOST_USER_SET_BACKEND_REQ_FD = 21,
85 VHOST_USER_IOTLB_MSG = 22,
86 VHOST_USER_SET_VRING_ENDIAN = 23,
87 VHOST_USER_GET_CONFIG = 24,
88 VHOST_USER_SET_CONFIG = 25,
89 VHOST_USER_CREATE_CRYPTO_SESSION = 26,
90 VHOST_USER_CLOSE_CRYPTO_SESSION = 27,
91 VHOST_USER_POSTCOPY_ADVISE = 28,
92 VHOST_USER_POSTCOPY_LISTEN = 29,
93 VHOST_USER_POSTCOPY_END = 30,
94 VHOST_USER_GET_INFLIGHT_FD = 31,
95 VHOST_USER_SET_INFLIGHT_FD = 32,
96 VHOST_USER_GPU_SET_SOCKET = 33,
97 VHOST_USER_RESET_DEVICE = 34,
98 /* Message number 35 reserved for VHOST_USER_VRING_KICK. */
99 VHOST_USER_GET_MAX_MEM_SLOTS = 36,
100 VHOST_USER_ADD_MEM_REG = 37,
101 VHOST_USER_REM_MEM_REG = 38,
102 VHOST_USER_SET_STATUS = 39,
103 VHOST_USER_GET_STATUS = 40,
104 VHOST_USER_GET_SHARED_OBJECT = 41,
105 VHOST_USER_SET_DEVICE_STATE_FD = 42,
106 VHOST_USER_CHECK_DEVICE_STATE = 43,
107 VHOST_USER_MAX
108 } VhostUserRequest;
109
110 typedef enum VhostUserBackendRequest {
111 VHOST_USER_BACKEND_NONE = 0,
112 VHOST_USER_BACKEND_IOTLB_MSG = 1,
113 VHOST_USER_BACKEND_CONFIG_CHANGE_MSG = 2,
114 VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG = 3,
115 VHOST_USER_BACKEND_SHARED_OBJECT_ADD = 6,
116 VHOST_USER_BACKEND_SHARED_OBJECT_REMOVE = 7,
117 VHOST_USER_BACKEND_SHARED_OBJECT_LOOKUP = 8,
118 VHOST_USER_BACKEND_MAX
119 } VhostUserBackendRequest;
120
121 typedef struct VhostUserMemoryRegion {
122 uint64_t guest_phys_addr;
123 uint64_t memory_size;
124 uint64_t userspace_addr;
125 uint64_t mmap_offset;
126 } VhostUserMemoryRegion;
127
128 typedef struct VhostUserMemory {
129 uint32_t nregions;
130 uint32_t padding;
131 VhostUserMemoryRegion regions[VHOST_MEMORY_BASELINE_NREGIONS];
132 } VhostUserMemory;
133
134 typedef struct VhostUserMemRegMsg {
135 uint64_t padding;
136 VhostUserMemoryRegion region;
137 } VhostUserMemRegMsg;
138
139 typedef struct VhostUserLog {
140 uint64_t mmap_size;
141 uint64_t mmap_offset;
142 } VhostUserLog;
143
144 typedef struct VhostUserConfig {
145 uint32_t offset;
146 uint32_t size;
147 uint32_t flags;
148 uint8_t region[VHOST_USER_MAX_CONFIG_SIZE];
149 } VhostUserConfig;
150
151 #define VHOST_CRYPTO_SYM_HMAC_MAX_KEY_LEN 512
152 #define VHOST_CRYPTO_SYM_CIPHER_MAX_KEY_LEN 64
153 #define VHOST_CRYPTO_ASYM_MAX_KEY_LEN 1024
154
155 typedef struct VhostUserCryptoSession {
156 uint64_t op_code;
157 union {
158 struct {
159 CryptoDevBackendSymSessionInfo session_setup_data;
160 uint8_t key[VHOST_CRYPTO_SYM_CIPHER_MAX_KEY_LEN];
161 uint8_t auth_key[VHOST_CRYPTO_SYM_HMAC_MAX_KEY_LEN];
162 } sym;
163 struct {
164 CryptoDevBackendAsymSessionInfo session_setup_data;
165 uint8_t key[VHOST_CRYPTO_ASYM_MAX_KEY_LEN];
166 } asym;
167 } u;
168
169 /* session id for success, -1 on errors */
170 int64_t session_id;
171 } VhostUserCryptoSession;
172
173 static VhostUserConfig c __attribute__ ((unused));
174 #define VHOST_USER_CONFIG_HDR_SIZE (sizeof(c.offset) \
175 + sizeof(c.size) \
176 + sizeof(c.flags))
177
178 typedef struct VhostUserVringArea {
179 uint64_t u64;
180 uint64_t size;
181 uint64_t offset;
182 } VhostUserVringArea;
183
184 typedef struct VhostUserInflight {
185 uint64_t mmap_size;
186 uint64_t mmap_offset;
187 uint16_t num_queues;
188 uint16_t queue_size;
189 } VhostUserInflight;
190
191 typedef struct VhostUserShared {
192 unsigned char uuid[16];
193 } VhostUserShared;
194
195 typedef struct {
196 VhostUserRequest request;
197
198 #define VHOST_USER_VERSION_MASK (0x3)
199 #define VHOST_USER_REPLY_MASK (0x1 << 2)
200 #define VHOST_USER_NEED_REPLY_MASK (0x1 << 3)
201 uint32_t flags;
202 uint32_t size; /* the following payload size */
203 } QEMU_PACKED VhostUserHeader;
204
205 /* Request payload of VHOST_USER_SET_DEVICE_STATE_FD */
206 typedef struct VhostUserTransferDeviceState {
207 uint32_t direction;
208 uint32_t phase;
209 } VhostUserTransferDeviceState;
210
211 typedef union {
212 #define VHOST_USER_VRING_IDX_MASK (0xff)
213 #define VHOST_USER_VRING_NOFD_MASK (0x1 << 8)
214 uint64_t u64;
215 struct vhost_vring_state state;
216 struct vhost_vring_addr addr;
217 VhostUserMemory memory;
218 VhostUserMemRegMsg mem_reg;
219 VhostUserLog log;
220 struct vhost_iotlb_msg iotlb;
221 VhostUserConfig config;
222 VhostUserCryptoSession session;
223 VhostUserVringArea area;
224 VhostUserInflight inflight;
225 VhostUserShared object;
226 VhostUserTransferDeviceState transfer_state;
227 } VhostUserPayload;
228
229 typedef struct VhostUserMsg {
230 VhostUserHeader hdr;
231 VhostUserPayload payload;
232 } QEMU_PACKED VhostUserMsg;
233
234 static VhostUserMsg m __attribute__ ((unused));
235 #define VHOST_USER_HDR_SIZE (sizeof(VhostUserHeader))
236
237 #define VHOST_USER_PAYLOAD_SIZE (sizeof(VhostUserPayload))
238
239 /* The version of the protocol we support */
240 #define VHOST_USER_VERSION (0x1)
241
242 struct vhost_user {
243 struct vhost_dev *dev;
244 /* Shared between vhost devs of the same virtio device */
245 VhostUserState *user;
246 QIOChannel *backend_ioc;
247 GSource *backend_src;
248 NotifierWithReturn postcopy_notifier;
249 struct PostCopyFD postcopy_fd;
250 uint64_t postcopy_client_bases[VHOST_USER_MAX_RAM_SLOTS];
251 /* Length of the region_rb and region_rb_offset arrays */
252 size_t region_rb_len;
253 /* RAMBlock associated with a given region */
254 RAMBlock **region_rb;
255 /*
256 * The offset from the start of the RAMBlock to the start of the
257 * vhost region.
258 */
259 ram_addr_t *region_rb_offset;
260
261 /* True once we've entered postcopy_listen */
262 bool postcopy_listen;
263
264 /* Our current regions */
265 int num_shadow_regions;
266 struct vhost_memory_region shadow_regions[VHOST_USER_MAX_RAM_SLOTS];
267 };
268
269 struct scrub_regions {
270 struct vhost_memory_region *region;
271 int reg_idx;
272 int fd_idx;
273 };
274
vhost_user_read_header(struct vhost_dev * dev,VhostUserMsg * msg)275 static int vhost_user_read_header(struct vhost_dev *dev, VhostUserMsg *msg)
276 {
277 struct vhost_user *u = dev->opaque;
278 CharBackend *chr = u->user->chr;
279 uint8_t *p = (uint8_t *) msg;
280 int r, size = VHOST_USER_HDR_SIZE;
281
282 r = qemu_chr_fe_read_all(chr, p, size);
283 if (r != size) {
284 int saved_errno = errno;
285 error_report("Failed to read msg header. Read %d instead of %d."
286 " Original request %d.", r, size, msg->hdr.request);
287 return r < 0 ? -saved_errno : -EIO;
288 }
289
290 /* validate received flags */
291 if (msg->hdr.flags != (VHOST_USER_REPLY_MASK | VHOST_USER_VERSION)) {
292 error_report("Failed to read msg header."
293 " Flags 0x%x instead of 0x%x.", msg->hdr.flags,
294 VHOST_USER_REPLY_MASK | VHOST_USER_VERSION);
295 return -EPROTO;
296 }
297
298 trace_vhost_user_read(msg->hdr.request, msg->hdr.flags);
299
300 return 0;
301 }
302
vhost_user_read(struct vhost_dev * dev,VhostUserMsg * msg)303 static int vhost_user_read(struct vhost_dev *dev, VhostUserMsg *msg)
304 {
305 struct vhost_user *u = dev->opaque;
306 CharBackend *chr = u->user->chr;
307 uint8_t *p = (uint8_t *) msg;
308 int r, size;
309
310 r = vhost_user_read_header(dev, msg);
311 if (r < 0) {
312 return r;
313 }
314
315 /* validate message size is sane */
316 if (msg->hdr.size > VHOST_USER_PAYLOAD_SIZE) {
317 error_report("Failed to read msg header."
318 " Size %d exceeds the maximum %zu.", msg->hdr.size,
319 VHOST_USER_PAYLOAD_SIZE);
320 return -EPROTO;
321 }
322
323 if (msg->hdr.size) {
324 p += VHOST_USER_HDR_SIZE;
325 size = msg->hdr.size;
326 r = qemu_chr_fe_read_all(chr, p, size);
327 if (r != size) {
328 int saved_errno = errno;
329 error_report("Failed to read msg payload."
330 " Read %d instead of %d.", r, msg->hdr.size);
331 return r < 0 ? -saved_errno : -EIO;
332 }
333 }
334
335 return 0;
336 }
337
process_message_reply(struct vhost_dev * dev,const VhostUserMsg * msg)338 static int process_message_reply(struct vhost_dev *dev,
339 const VhostUserMsg *msg)
340 {
341 int ret;
342 VhostUserMsg msg_reply;
343
344 if ((msg->hdr.flags & VHOST_USER_NEED_REPLY_MASK) == 0) {
345 return 0;
346 }
347
348 ret = vhost_user_read(dev, &msg_reply);
349 if (ret < 0) {
350 return ret;
351 }
352
353 if (msg_reply.hdr.request != msg->hdr.request) {
354 error_report("Received unexpected msg type. "
355 "Expected %d received %d",
356 msg->hdr.request, msg_reply.hdr.request);
357 return -EPROTO;
358 }
359
360 return msg_reply.payload.u64 ? -EIO : 0;
361 }
362
vhost_user_per_device_request(VhostUserRequest request)363 static bool vhost_user_per_device_request(VhostUserRequest request)
364 {
365 switch (request) {
366 case VHOST_USER_SET_OWNER:
367 case VHOST_USER_RESET_OWNER:
368 case VHOST_USER_SET_MEM_TABLE:
369 case VHOST_USER_GET_QUEUE_NUM:
370 case VHOST_USER_NET_SET_MTU:
371 case VHOST_USER_RESET_DEVICE:
372 case VHOST_USER_ADD_MEM_REG:
373 case VHOST_USER_REM_MEM_REG:
374 case VHOST_USER_SET_LOG_BASE:
375 return true;
376 default:
377 return false;
378 }
379 }
380
381 /* most non-init callers ignore the error */
vhost_user_write(struct vhost_dev * dev,VhostUserMsg * msg,int * fds,int fd_num)382 static int vhost_user_write(struct vhost_dev *dev, VhostUserMsg *msg,
383 int *fds, int fd_num)
384 {
385 struct vhost_user *u = dev->opaque;
386 CharBackend *chr = u->user->chr;
387 int ret, size = VHOST_USER_HDR_SIZE + msg->hdr.size;
388
389 /*
390 * Some devices, like virtio-scsi, are implemented as a single vhost_dev,
391 * while others, like virtio-net, contain multiple vhost_devs. For
392 * operations such as configuring device memory mappings or issuing device
393 * resets, which affect the whole device instead of individual VQs,
394 * vhost-user messages should only be sent once.
395 *
396 * Devices with multiple vhost_devs are given an associated dev->vq_index
397 * so per_device requests are only sent if vq_index is 0.
398 */
399 if (vhost_user_per_device_request(msg->hdr.request)
400 && dev->vq_index != 0) {
401 msg->hdr.flags &= ~VHOST_USER_NEED_REPLY_MASK;
402 return 0;
403 }
404
405 if (qemu_chr_fe_set_msgfds(chr, fds, fd_num) < 0) {
406 error_report("Failed to set msg fds.");
407 return -EINVAL;
408 }
409
410 ret = qemu_chr_fe_write_all(chr, (const uint8_t *) msg, size);
411 if (ret != size) {
412 int saved_errno = errno;
413 error_report("Failed to write msg."
414 " Wrote %d instead of %d.", ret, size);
415 return ret < 0 ? -saved_errno : -EIO;
416 }
417
418 trace_vhost_user_write(msg->hdr.request, msg->hdr.flags);
419
420 return 0;
421 }
422
vhost_user_gpu_set_socket(struct vhost_dev * dev,int fd)423 int vhost_user_gpu_set_socket(struct vhost_dev *dev, int fd)
424 {
425 VhostUserMsg msg = {
426 .hdr.request = VHOST_USER_GPU_SET_SOCKET,
427 .hdr.flags = VHOST_USER_VERSION,
428 };
429
430 return vhost_user_write(dev, &msg, &fd, 1);
431 }
432
vhost_user_set_log_base(struct vhost_dev * dev,uint64_t base,struct vhost_log * log)433 static int vhost_user_set_log_base(struct vhost_dev *dev, uint64_t base,
434 struct vhost_log *log)
435 {
436 int fds[VHOST_USER_MAX_RAM_SLOTS];
437 size_t fd_num = 0;
438 bool shmfd = virtio_has_feature(dev->protocol_features,
439 VHOST_USER_PROTOCOL_F_LOG_SHMFD);
440 int ret;
441 VhostUserMsg msg = {
442 .hdr.request = VHOST_USER_SET_LOG_BASE,
443 .hdr.flags = VHOST_USER_VERSION,
444 .payload.log.mmap_size = log->size * sizeof(*(log->log)),
445 .payload.log.mmap_offset = 0,
446 .hdr.size = sizeof(msg.payload.log),
447 };
448
449 /* Send only once with first queue pair */
450 if (dev->vq_index != 0) {
451 return 0;
452 }
453
454 if (shmfd && log->fd != -1) {
455 fds[fd_num++] = log->fd;
456 }
457
458 ret = vhost_user_write(dev, &msg, fds, fd_num);
459 if (ret < 0) {
460 return ret;
461 }
462
463 if (shmfd) {
464 msg.hdr.size = 0;
465 ret = vhost_user_read(dev, &msg);
466 if (ret < 0) {
467 return ret;
468 }
469
470 if (msg.hdr.request != VHOST_USER_SET_LOG_BASE) {
471 error_report("Received unexpected msg type. "
472 "Expected %d received %d",
473 VHOST_USER_SET_LOG_BASE, msg.hdr.request);
474 return -EPROTO;
475 }
476 }
477
478 return 0;
479 }
480
vhost_user_get_mr_data(uint64_t addr,ram_addr_t * offset,int * fd)481 static MemoryRegion *vhost_user_get_mr_data(uint64_t addr, ram_addr_t *offset,
482 int *fd)
483 {
484 MemoryRegion *mr;
485
486 assert((uintptr_t)addr == addr);
487 mr = memory_region_from_host((void *)(uintptr_t)addr, offset);
488 *fd = memory_region_get_fd(mr);
489 *offset += mr->ram_block->fd_offset;
490
491 return mr;
492 }
493
vhost_user_fill_msg_region(VhostUserMemoryRegion * dst,struct vhost_memory_region * src,uint64_t mmap_offset)494 static void vhost_user_fill_msg_region(VhostUserMemoryRegion *dst,
495 struct vhost_memory_region *src,
496 uint64_t mmap_offset)
497 {
498 assert(src != NULL && dst != NULL);
499 dst->userspace_addr = src->userspace_addr;
500 dst->memory_size = src->memory_size;
501 dst->guest_phys_addr = src->guest_phys_addr;
502 dst->mmap_offset = mmap_offset;
503 }
504
vhost_user_fill_set_mem_table_msg(struct vhost_user * u,struct vhost_dev * dev,VhostUserMsg * msg,int * fds,size_t * fd_num,bool track_ramblocks)505 static int vhost_user_fill_set_mem_table_msg(struct vhost_user *u,
506 struct vhost_dev *dev,
507 VhostUserMsg *msg,
508 int *fds, size_t *fd_num,
509 bool track_ramblocks)
510 {
511 int i, fd;
512 ram_addr_t offset;
513 MemoryRegion *mr;
514 struct vhost_memory_region *reg;
515 VhostUserMemoryRegion region_buffer;
516
517 msg->hdr.request = VHOST_USER_SET_MEM_TABLE;
518
519 for (i = 0; i < dev->mem->nregions; ++i) {
520 reg = dev->mem->regions + i;
521
522 mr = vhost_user_get_mr_data(reg->userspace_addr, &offset, &fd);
523 if (fd > 0) {
524 if (track_ramblocks) {
525 assert(*fd_num < VHOST_MEMORY_BASELINE_NREGIONS);
526 trace_vhost_user_set_mem_table_withfd(*fd_num, mr->name,
527 reg->memory_size,
528 reg->guest_phys_addr,
529 reg->userspace_addr,
530 offset);
531 u->region_rb_offset[i] = offset;
532 u->region_rb[i] = mr->ram_block;
533 } else if (*fd_num == VHOST_MEMORY_BASELINE_NREGIONS) {
534 error_report("Failed preparing vhost-user memory table msg");
535 return -ENOBUFS;
536 }
537 vhost_user_fill_msg_region(®ion_buffer, reg, offset);
538 msg->payload.memory.regions[*fd_num] = region_buffer;
539 fds[(*fd_num)++] = fd;
540 } else if (track_ramblocks) {
541 u->region_rb_offset[i] = 0;
542 u->region_rb[i] = NULL;
543 }
544 }
545
546 msg->payload.memory.nregions = *fd_num;
547
548 if (!*fd_num) {
549 error_report("Failed initializing vhost-user memory map, "
550 "consider using -object memory-backend-file share=on");
551 return -EINVAL;
552 }
553
554 msg->hdr.size = sizeof(msg->payload.memory.nregions);
555 msg->hdr.size += sizeof(msg->payload.memory.padding);
556 msg->hdr.size += *fd_num * sizeof(VhostUserMemoryRegion);
557
558 return 0;
559 }
560
reg_equal(struct vhost_memory_region * shadow_reg,struct vhost_memory_region * vdev_reg)561 static inline bool reg_equal(struct vhost_memory_region *shadow_reg,
562 struct vhost_memory_region *vdev_reg)
563 {
564 return shadow_reg->guest_phys_addr == vdev_reg->guest_phys_addr &&
565 shadow_reg->userspace_addr == vdev_reg->userspace_addr &&
566 shadow_reg->memory_size == vdev_reg->memory_size;
567 }
568
scrub_shadow_regions(struct vhost_dev * dev,struct scrub_regions * add_reg,int * nr_add_reg,struct scrub_regions * rem_reg,int * nr_rem_reg,uint64_t * shadow_pcb,bool track_ramblocks)569 static void scrub_shadow_regions(struct vhost_dev *dev,
570 struct scrub_regions *add_reg,
571 int *nr_add_reg,
572 struct scrub_regions *rem_reg,
573 int *nr_rem_reg, uint64_t *shadow_pcb,
574 bool track_ramblocks)
575 {
576 struct vhost_user *u = dev->opaque;
577 bool found[VHOST_USER_MAX_RAM_SLOTS] = {};
578 struct vhost_memory_region *reg, *shadow_reg;
579 int i, j, fd, add_idx = 0, rm_idx = 0, fd_num = 0;
580 ram_addr_t offset;
581 MemoryRegion *mr;
582 bool matching;
583
584 /*
585 * Find memory regions present in our shadow state which are not in
586 * the device's current memory state.
587 *
588 * Mark regions in both the shadow and device state as "found".
589 */
590 for (i = 0; i < u->num_shadow_regions; i++) {
591 shadow_reg = &u->shadow_regions[i];
592 matching = false;
593
594 for (j = 0; j < dev->mem->nregions; j++) {
595 reg = &dev->mem->regions[j];
596
597 mr = vhost_user_get_mr_data(reg->userspace_addr, &offset, &fd);
598
599 if (reg_equal(shadow_reg, reg)) {
600 matching = true;
601 found[j] = true;
602 if (track_ramblocks) {
603 /*
604 * Reset postcopy client bases, region_rb, and
605 * region_rb_offset in case regions are removed.
606 */
607 if (fd > 0) {
608 u->region_rb_offset[j] = offset;
609 u->region_rb[j] = mr->ram_block;
610 shadow_pcb[j] = u->postcopy_client_bases[i];
611 } else {
612 u->region_rb_offset[j] = 0;
613 u->region_rb[j] = NULL;
614 }
615 }
616 break;
617 }
618 }
619
620 /*
621 * If the region was not found in the current device memory state
622 * create an entry for it in the removed list.
623 */
624 if (!matching) {
625 rem_reg[rm_idx].region = shadow_reg;
626 rem_reg[rm_idx++].reg_idx = i;
627 }
628 }
629
630 /*
631 * For regions not marked "found", create entries in the added list.
632 *
633 * Note their indexes in the device memory state and the indexes of their
634 * file descriptors.
635 */
636 for (i = 0; i < dev->mem->nregions; i++) {
637 reg = &dev->mem->regions[i];
638 vhost_user_get_mr_data(reg->userspace_addr, &offset, &fd);
639 if (fd > 0) {
640 ++fd_num;
641 }
642
643 /*
644 * If the region was in both the shadow and device state we don't
645 * need to send a VHOST_USER_ADD_MEM_REG message for it.
646 */
647 if (found[i]) {
648 continue;
649 }
650
651 add_reg[add_idx].region = reg;
652 add_reg[add_idx].reg_idx = i;
653 add_reg[add_idx++].fd_idx = fd_num;
654 }
655 *nr_rem_reg = rm_idx;
656 *nr_add_reg = add_idx;
657
658 return;
659 }
660
send_remove_regions(struct vhost_dev * dev,struct scrub_regions * remove_reg,int nr_rem_reg,VhostUserMsg * msg,bool reply_supported)661 static int send_remove_regions(struct vhost_dev *dev,
662 struct scrub_regions *remove_reg,
663 int nr_rem_reg, VhostUserMsg *msg,
664 bool reply_supported)
665 {
666 struct vhost_user *u = dev->opaque;
667 struct vhost_memory_region *shadow_reg;
668 int i, fd, shadow_reg_idx, ret;
669 ram_addr_t offset;
670 VhostUserMemoryRegion region_buffer;
671
672 /*
673 * The regions in remove_reg appear in the same order they do in the
674 * shadow table. Therefore we can minimize memory copies by iterating
675 * through remove_reg backwards.
676 */
677 for (i = nr_rem_reg - 1; i >= 0; i--) {
678 shadow_reg = remove_reg[i].region;
679 shadow_reg_idx = remove_reg[i].reg_idx;
680
681 vhost_user_get_mr_data(shadow_reg->userspace_addr, &offset, &fd);
682
683 if (fd > 0) {
684 msg->hdr.request = VHOST_USER_REM_MEM_REG;
685 vhost_user_fill_msg_region(®ion_buffer, shadow_reg, 0);
686 msg->payload.mem_reg.region = region_buffer;
687
688 ret = vhost_user_write(dev, msg, NULL, 0);
689 if (ret < 0) {
690 return ret;
691 }
692
693 if (reply_supported) {
694 ret = process_message_reply(dev, msg);
695 if (ret) {
696 return ret;
697 }
698 }
699 }
700
701 /*
702 * At this point we know the backend has unmapped the region. It is now
703 * safe to remove it from the shadow table.
704 */
705 memmove(&u->shadow_regions[shadow_reg_idx],
706 &u->shadow_regions[shadow_reg_idx + 1],
707 sizeof(struct vhost_memory_region) *
708 (u->num_shadow_regions - shadow_reg_idx - 1));
709 u->num_shadow_regions--;
710 }
711
712 return 0;
713 }
714
send_add_regions(struct vhost_dev * dev,struct scrub_regions * add_reg,int nr_add_reg,VhostUserMsg * msg,uint64_t * shadow_pcb,bool reply_supported,bool track_ramblocks)715 static int send_add_regions(struct vhost_dev *dev,
716 struct scrub_regions *add_reg, int nr_add_reg,
717 VhostUserMsg *msg, uint64_t *shadow_pcb,
718 bool reply_supported, bool track_ramblocks)
719 {
720 struct vhost_user *u = dev->opaque;
721 int i, fd, ret, reg_idx, reg_fd_idx;
722 struct vhost_memory_region *reg;
723 MemoryRegion *mr;
724 ram_addr_t offset;
725 VhostUserMsg msg_reply;
726 VhostUserMemoryRegion region_buffer;
727
728 for (i = 0; i < nr_add_reg; i++) {
729 reg = add_reg[i].region;
730 reg_idx = add_reg[i].reg_idx;
731 reg_fd_idx = add_reg[i].fd_idx;
732
733 mr = vhost_user_get_mr_data(reg->userspace_addr, &offset, &fd);
734
735 if (fd > 0) {
736 if (track_ramblocks) {
737 trace_vhost_user_set_mem_table_withfd(reg_fd_idx, mr->name,
738 reg->memory_size,
739 reg->guest_phys_addr,
740 reg->userspace_addr,
741 offset);
742 u->region_rb_offset[reg_idx] = offset;
743 u->region_rb[reg_idx] = mr->ram_block;
744 }
745 msg->hdr.request = VHOST_USER_ADD_MEM_REG;
746 vhost_user_fill_msg_region(®ion_buffer, reg, offset);
747 msg->payload.mem_reg.region = region_buffer;
748
749 ret = vhost_user_write(dev, msg, &fd, 1);
750 if (ret < 0) {
751 return ret;
752 }
753
754 if (track_ramblocks) {
755 uint64_t reply_gpa;
756
757 ret = vhost_user_read(dev, &msg_reply);
758 if (ret < 0) {
759 return ret;
760 }
761
762 reply_gpa = msg_reply.payload.mem_reg.region.guest_phys_addr;
763
764 if (msg_reply.hdr.request != VHOST_USER_ADD_MEM_REG) {
765 error_report("%s: Received unexpected msg type."
766 "Expected %d received %d", __func__,
767 VHOST_USER_ADD_MEM_REG,
768 msg_reply.hdr.request);
769 return -EPROTO;
770 }
771
772 /*
773 * We're using the same structure, just reusing one of the
774 * fields, so it should be the same size.
775 */
776 if (msg_reply.hdr.size != msg->hdr.size) {
777 error_report("%s: Unexpected size for postcopy reply "
778 "%d vs %d", __func__, msg_reply.hdr.size,
779 msg->hdr.size);
780 return -EPROTO;
781 }
782
783 /* Get the postcopy client base from the backend's reply. */
784 if (reply_gpa == dev->mem->regions[reg_idx].guest_phys_addr) {
785 shadow_pcb[reg_idx] =
786 msg_reply.payload.mem_reg.region.userspace_addr;
787 trace_vhost_user_set_mem_table_postcopy(
788 msg_reply.payload.mem_reg.region.userspace_addr,
789 msg->payload.mem_reg.region.userspace_addr,
790 reg_fd_idx, reg_idx);
791 } else {
792 error_report("%s: invalid postcopy reply for region. "
793 "Got guest physical address %" PRIX64 ", expected "
794 "%" PRIX64, __func__, reply_gpa,
795 dev->mem->regions[reg_idx].guest_phys_addr);
796 return -EPROTO;
797 }
798 } else if (reply_supported) {
799 ret = process_message_reply(dev, msg);
800 if (ret) {
801 return ret;
802 }
803 }
804 } else if (track_ramblocks) {
805 u->region_rb_offset[reg_idx] = 0;
806 u->region_rb[reg_idx] = NULL;
807 }
808
809 /*
810 * At this point, we know the backend has mapped in the new
811 * region, if the region has a valid file descriptor.
812 *
813 * The region should now be added to the shadow table.
814 */
815 u->shadow_regions[u->num_shadow_regions].guest_phys_addr =
816 reg->guest_phys_addr;
817 u->shadow_regions[u->num_shadow_regions].userspace_addr =
818 reg->userspace_addr;
819 u->shadow_regions[u->num_shadow_regions].memory_size =
820 reg->memory_size;
821 u->num_shadow_regions++;
822 }
823
824 return 0;
825 }
826
vhost_user_add_remove_regions(struct vhost_dev * dev,VhostUserMsg * msg,bool reply_supported,bool track_ramblocks)827 static int vhost_user_add_remove_regions(struct vhost_dev *dev,
828 VhostUserMsg *msg,
829 bool reply_supported,
830 bool track_ramblocks)
831 {
832 struct vhost_user *u = dev->opaque;
833 struct scrub_regions add_reg[VHOST_USER_MAX_RAM_SLOTS];
834 struct scrub_regions rem_reg[VHOST_USER_MAX_RAM_SLOTS];
835 uint64_t shadow_pcb[VHOST_USER_MAX_RAM_SLOTS] = {};
836 int nr_add_reg, nr_rem_reg;
837 int ret;
838
839 msg->hdr.size = sizeof(msg->payload.mem_reg);
840
841 /* Find the regions which need to be removed or added. */
842 scrub_shadow_regions(dev, add_reg, &nr_add_reg, rem_reg, &nr_rem_reg,
843 shadow_pcb, track_ramblocks);
844
845 if (nr_rem_reg) {
846 ret = send_remove_regions(dev, rem_reg, nr_rem_reg, msg,
847 reply_supported);
848 if (ret < 0) {
849 goto err;
850 }
851 }
852
853 if (nr_add_reg) {
854 ret = send_add_regions(dev, add_reg, nr_add_reg, msg, shadow_pcb,
855 reply_supported, track_ramblocks);
856 if (ret < 0) {
857 goto err;
858 }
859 }
860
861 if (track_ramblocks) {
862 memcpy(u->postcopy_client_bases, shadow_pcb,
863 sizeof(uint64_t) * VHOST_USER_MAX_RAM_SLOTS);
864 /*
865 * Now we've registered this with the postcopy code, we ack to the
866 * client, because now we're in the position to be able to deal with
867 * any faults it generates.
868 */
869 /* TODO: Use this for failure cases as well with a bad value. */
870 msg->hdr.size = sizeof(msg->payload.u64);
871 msg->payload.u64 = 0; /* OK */
872
873 ret = vhost_user_write(dev, msg, NULL, 0);
874 if (ret < 0) {
875 return ret;
876 }
877 }
878
879 return 0;
880
881 err:
882 if (track_ramblocks) {
883 memcpy(u->postcopy_client_bases, shadow_pcb,
884 sizeof(uint64_t) * VHOST_USER_MAX_RAM_SLOTS);
885 }
886
887 return ret;
888 }
889
vhost_user_set_mem_table_postcopy(struct vhost_dev * dev,struct vhost_memory * mem,bool reply_supported,bool config_mem_slots)890 static int vhost_user_set_mem_table_postcopy(struct vhost_dev *dev,
891 struct vhost_memory *mem,
892 bool reply_supported,
893 bool config_mem_slots)
894 {
895 struct vhost_user *u = dev->opaque;
896 int fds[VHOST_MEMORY_BASELINE_NREGIONS];
897 size_t fd_num = 0;
898 VhostUserMsg msg_reply;
899 int region_i, msg_i;
900 int ret;
901
902 VhostUserMsg msg = {
903 .hdr.flags = VHOST_USER_VERSION,
904 };
905
906 if (u->region_rb_len < dev->mem->nregions) {
907 u->region_rb = g_renew(RAMBlock*, u->region_rb, dev->mem->nregions);
908 u->region_rb_offset = g_renew(ram_addr_t, u->region_rb_offset,
909 dev->mem->nregions);
910 memset(&(u->region_rb[u->region_rb_len]), '\0',
911 sizeof(RAMBlock *) * (dev->mem->nregions - u->region_rb_len));
912 memset(&(u->region_rb_offset[u->region_rb_len]), '\0',
913 sizeof(ram_addr_t) * (dev->mem->nregions - u->region_rb_len));
914 u->region_rb_len = dev->mem->nregions;
915 }
916
917 if (config_mem_slots) {
918 ret = vhost_user_add_remove_regions(dev, &msg, reply_supported, true);
919 if (ret < 0) {
920 return ret;
921 }
922 } else {
923 ret = vhost_user_fill_set_mem_table_msg(u, dev, &msg, fds, &fd_num,
924 true);
925 if (ret < 0) {
926 return ret;
927 }
928
929 ret = vhost_user_write(dev, &msg, fds, fd_num);
930 if (ret < 0) {
931 return ret;
932 }
933
934 ret = vhost_user_read(dev, &msg_reply);
935 if (ret < 0) {
936 return ret;
937 }
938
939 if (msg_reply.hdr.request != VHOST_USER_SET_MEM_TABLE) {
940 error_report("%s: Received unexpected msg type."
941 "Expected %d received %d", __func__,
942 VHOST_USER_SET_MEM_TABLE, msg_reply.hdr.request);
943 return -EPROTO;
944 }
945
946 /*
947 * We're using the same structure, just reusing one of the
948 * fields, so it should be the same size.
949 */
950 if (msg_reply.hdr.size != msg.hdr.size) {
951 error_report("%s: Unexpected size for postcopy reply "
952 "%d vs %d", __func__, msg_reply.hdr.size,
953 msg.hdr.size);
954 return -EPROTO;
955 }
956
957 memset(u->postcopy_client_bases, 0,
958 sizeof(uint64_t) * VHOST_USER_MAX_RAM_SLOTS);
959
960 /*
961 * They're in the same order as the regions that were sent
962 * but some of the regions were skipped (above) if they
963 * didn't have fd's
964 */
965 for (msg_i = 0, region_i = 0;
966 region_i < dev->mem->nregions;
967 region_i++) {
968 if (msg_i < fd_num &&
969 msg_reply.payload.memory.regions[msg_i].guest_phys_addr ==
970 dev->mem->regions[region_i].guest_phys_addr) {
971 u->postcopy_client_bases[region_i] =
972 msg_reply.payload.memory.regions[msg_i].userspace_addr;
973 trace_vhost_user_set_mem_table_postcopy(
974 msg_reply.payload.memory.regions[msg_i].userspace_addr,
975 msg.payload.memory.regions[msg_i].userspace_addr,
976 msg_i, region_i);
977 msg_i++;
978 }
979 }
980 if (msg_i != fd_num) {
981 error_report("%s: postcopy reply not fully consumed "
982 "%d vs %zd",
983 __func__, msg_i, fd_num);
984 return -EIO;
985 }
986
987 /*
988 * Now we've registered this with the postcopy code, we ack to the
989 * client, because now we're in the position to be able to deal
990 * with any faults it generates.
991 */
992 /* TODO: Use this for failure cases as well with a bad value. */
993 msg.hdr.size = sizeof(msg.payload.u64);
994 msg.payload.u64 = 0; /* OK */
995 ret = vhost_user_write(dev, &msg, NULL, 0);
996 if (ret < 0) {
997 return ret;
998 }
999 }
1000
1001 return 0;
1002 }
1003
vhost_user_set_mem_table(struct vhost_dev * dev,struct vhost_memory * mem)1004 static int vhost_user_set_mem_table(struct vhost_dev *dev,
1005 struct vhost_memory *mem)
1006 {
1007 struct vhost_user *u = dev->opaque;
1008 int fds[VHOST_MEMORY_BASELINE_NREGIONS];
1009 size_t fd_num = 0;
1010 bool do_postcopy = u->postcopy_listen && u->postcopy_fd.handler;
1011 bool reply_supported = virtio_has_feature(dev->protocol_features,
1012 VHOST_USER_PROTOCOL_F_REPLY_ACK);
1013 bool config_mem_slots =
1014 virtio_has_feature(dev->protocol_features,
1015 VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS);
1016 int ret;
1017
1018 if (do_postcopy) {
1019 /*
1020 * Postcopy has enough differences that it's best done in it's own
1021 * version
1022 */
1023 return vhost_user_set_mem_table_postcopy(dev, mem, reply_supported,
1024 config_mem_slots);
1025 }
1026
1027 VhostUserMsg msg = {
1028 .hdr.flags = VHOST_USER_VERSION,
1029 };
1030
1031 if (reply_supported) {
1032 msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
1033 }
1034
1035 if (config_mem_slots) {
1036 ret = vhost_user_add_remove_regions(dev, &msg, reply_supported, false);
1037 if (ret < 0) {
1038 return ret;
1039 }
1040 } else {
1041 ret = vhost_user_fill_set_mem_table_msg(u, dev, &msg, fds, &fd_num,
1042 false);
1043 if (ret < 0) {
1044 return ret;
1045 }
1046
1047 ret = vhost_user_write(dev, &msg, fds, fd_num);
1048 if (ret < 0) {
1049 return ret;
1050 }
1051
1052 if (reply_supported) {
1053 return process_message_reply(dev, &msg);
1054 }
1055 }
1056
1057 return 0;
1058 }
1059
vhost_user_set_vring_endian(struct vhost_dev * dev,struct vhost_vring_state * ring)1060 static int vhost_user_set_vring_endian(struct vhost_dev *dev,
1061 struct vhost_vring_state *ring)
1062 {
1063 bool cross_endian = virtio_has_feature(dev->protocol_features,
1064 VHOST_USER_PROTOCOL_F_CROSS_ENDIAN);
1065 VhostUserMsg msg = {
1066 .hdr.request = VHOST_USER_SET_VRING_ENDIAN,
1067 .hdr.flags = VHOST_USER_VERSION,
1068 .payload.state = *ring,
1069 .hdr.size = sizeof(msg.payload.state),
1070 };
1071
1072 if (!cross_endian) {
1073 error_report("vhost-user trying to send unhandled ioctl");
1074 return -ENOTSUP;
1075 }
1076
1077 return vhost_user_write(dev, &msg, NULL, 0);
1078 }
1079
vhost_user_get_u64(struct vhost_dev * dev,int request,uint64_t * u64)1080 static int vhost_user_get_u64(struct vhost_dev *dev, int request, uint64_t *u64)
1081 {
1082 int ret;
1083 VhostUserMsg msg = {
1084 .hdr.request = request,
1085 .hdr.flags = VHOST_USER_VERSION,
1086 };
1087
1088 if (vhost_user_per_device_request(request) && dev->vq_index != 0) {
1089 return 0;
1090 }
1091
1092 ret = vhost_user_write(dev, &msg, NULL, 0);
1093 if (ret < 0) {
1094 return ret;
1095 }
1096
1097 ret = vhost_user_read(dev, &msg);
1098 if (ret < 0) {
1099 return ret;
1100 }
1101
1102 if (msg.hdr.request != request) {
1103 error_report("Received unexpected msg type. Expected %d received %d",
1104 request, msg.hdr.request);
1105 return -EPROTO;
1106 }
1107
1108 if (msg.hdr.size != sizeof(msg.payload.u64)) {
1109 error_report("Received bad msg size.");
1110 return -EPROTO;
1111 }
1112
1113 *u64 = msg.payload.u64;
1114
1115 return 0;
1116 }
1117
vhost_user_get_features(struct vhost_dev * dev,uint64_t * features)1118 static int vhost_user_get_features(struct vhost_dev *dev, uint64_t *features)
1119 {
1120 if (vhost_user_get_u64(dev, VHOST_USER_GET_FEATURES, features) < 0) {
1121 return -EPROTO;
1122 }
1123
1124 return 0;
1125 }
1126
1127 /* Note: "msg->hdr.flags" may be modified. */
vhost_user_write_sync(struct vhost_dev * dev,VhostUserMsg * msg,bool wait_for_reply)1128 static int vhost_user_write_sync(struct vhost_dev *dev, VhostUserMsg *msg,
1129 bool wait_for_reply)
1130 {
1131 int ret;
1132
1133 if (wait_for_reply) {
1134 bool reply_supported = virtio_has_feature(dev->protocol_features,
1135 VHOST_USER_PROTOCOL_F_REPLY_ACK);
1136 if (reply_supported) {
1137 msg->hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
1138 }
1139 }
1140
1141 ret = vhost_user_write(dev, msg, NULL, 0);
1142 if (ret < 0) {
1143 return ret;
1144 }
1145
1146 if (wait_for_reply) {
1147 uint64_t dummy;
1148
1149 if (msg->hdr.flags & VHOST_USER_NEED_REPLY_MASK) {
1150 return process_message_reply(dev, msg);
1151 }
1152
1153 /*
1154 * We need to wait for a reply but the backend does not
1155 * support replies for the command we just sent.
1156 * Send VHOST_USER_GET_FEATURES which makes all backends
1157 * send a reply.
1158 */
1159 return vhost_user_get_features(dev, &dummy);
1160 }
1161
1162 return 0;
1163 }
1164
vhost_set_vring(struct vhost_dev * dev,unsigned long int request,struct vhost_vring_state * ring,bool wait_for_reply)1165 static int vhost_set_vring(struct vhost_dev *dev,
1166 unsigned long int request,
1167 struct vhost_vring_state *ring,
1168 bool wait_for_reply)
1169 {
1170 VhostUserMsg msg = {
1171 .hdr.request = request,
1172 .hdr.flags = VHOST_USER_VERSION,
1173 .payload.state = *ring,
1174 .hdr.size = sizeof(msg.payload.state),
1175 };
1176
1177 return vhost_user_write_sync(dev, &msg, wait_for_reply);
1178 }
1179
vhost_user_set_vring_num(struct vhost_dev * dev,struct vhost_vring_state * ring)1180 static int vhost_user_set_vring_num(struct vhost_dev *dev,
1181 struct vhost_vring_state *ring)
1182 {
1183 return vhost_set_vring(dev, VHOST_USER_SET_VRING_NUM, ring, false);
1184 }
1185
vhost_user_host_notifier_free(VhostUserHostNotifier * n)1186 static void vhost_user_host_notifier_free(VhostUserHostNotifier *n)
1187 {
1188 assert(n && n->unmap_addr);
1189 munmap(n->unmap_addr, qemu_real_host_page_size());
1190 n->unmap_addr = NULL;
1191 }
1192
1193 /*
1194 * clean-up function for notifier, will finally free the structure
1195 * under rcu.
1196 */
vhost_user_host_notifier_remove(VhostUserHostNotifier * n,VirtIODevice * vdev)1197 static void vhost_user_host_notifier_remove(VhostUserHostNotifier *n,
1198 VirtIODevice *vdev)
1199 {
1200 if (n->addr) {
1201 if (vdev) {
1202 virtio_queue_set_host_notifier_mr(vdev, n->idx, &n->mr, false);
1203 }
1204 assert(!n->unmap_addr);
1205 n->unmap_addr = n->addr;
1206 n->addr = NULL;
1207 call_rcu(n, vhost_user_host_notifier_free, rcu);
1208 }
1209 }
1210
vhost_user_set_vring_base(struct vhost_dev * dev,struct vhost_vring_state * ring)1211 static int vhost_user_set_vring_base(struct vhost_dev *dev,
1212 struct vhost_vring_state *ring)
1213 {
1214 return vhost_set_vring(dev, VHOST_USER_SET_VRING_BASE, ring, false);
1215 }
1216
vhost_user_set_vring_enable(struct vhost_dev * dev,int enable)1217 static int vhost_user_set_vring_enable(struct vhost_dev *dev, int enable)
1218 {
1219 int i;
1220
1221 if (!virtio_has_feature(dev->features, VHOST_USER_F_PROTOCOL_FEATURES)) {
1222 return -EINVAL;
1223 }
1224
1225 for (i = 0; i < dev->nvqs; ++i) {
1226 int ret;
1227 struct vhost_vring_state state = {
1228 .index = dev->vq_index + i,
1229 .num = enable,
1230 };
1231
1232 /*
1233 * SET_VRING_ENABLE travels from guest to QEMU to vhost-user backend /
1234 * control plane thread via unix domain socket. Virtio requests travel
1235 * from guest to vhost-user backend / data plane thread via eventfd.
1236 * Even if the guest enables the ring first, and pushes its first virtio
1237 * request second (conforming to the virtio spec), the data plane thread
1238 * in the backend may see the virtio request before the control plane
1239 * thread sees the queue enablement. This causes (in fact, requires) the
1240 * data plane thread to discard the virtio request (it arrived on a
1241 * seemingly disabled queue). To prevent this out-of-order delivery,
1242 * don't let the guest proceed to pushing the virtio request until the
1243 * backend control plane acknowledges enabling the queue -- IOW, pass
1244 * wait_for_reply=true below.
1245 */
1246 ret = vhost_set_vring(dev, VHOST_USER_SET_VRING_ENABLE, &state, true);
1247 if (ret < 0) {
1248 /*
1249 * Restoring the previous state is likely infeasible, as well as
1250 * proceeding regardless the error, so just bail out and hope for
1251 * the device-level recovery.
1252 */
1253 return ret;
1254 }
1255 }
1256
1257 return 0;
1258 }
1259
fetch_notifier(VhostUserState * u,int idx)1260 static VhostUserHostNotifier *fetch_notifier(VhostUserState *u,
1261 int idx)
1262 {
1263 if (idx >= u->notifiers->len) {
1264 return NULL;
1265 }
1266 return g_ptr_array_index(u->notifiers, idx);
1267 }
1268
vhost_user_get_vring_base(struct vhost_dev * dev,struct vhost_vring_state * ring)1269 static int vhost_user_get_vring_base(struct vhost_dev *dev,
1270 struct vhost_vring_state *ring)
1271 {
1272 int ret;
1273 VhostUserMsg msg = {
1274 .hdr.request = VHOST_USER_GET_VRING_BASE,
1275 .hdr.flags = VHOST_USER_VERSION,
1276 .payload.state = *ring,
1277 .hdr.size = sizeof(msg.payload.state),
1278 };
1279 struct vhost_user *u = dev->opaque;
1280
1281 VhostUserHostNotifier *n = fetch_notifier(u->user, ring->index);
1282 if (n) {
1283 vhost_user_host_notifier_remove(n, dev->vdev);
1284 }
1285
1286 ret = vhost_user_write(dev, &msg, NULL, 0);
1287 if (ret < 0) {
1288 return ret;
1289 }
1290
1291 ret = vhost_user_read(dev, &msg);
1292 if (ret < 0) {
1293 return ret;
1294 }
1295
1296 if (msg.hdr.request != VHOST_USER_GET_VRING_BASE) {
1297 error_report("Received unexpected msg type. Expected %d received %d",
1298 VHOST_USER_GET_VRING_BASE, msg.hdr.request);
1299 return -EPROTO;
1300 }
1301
1302 if (msg.hdr.size != sizeof(msg.payload.state)) {
1303 error_report("Received bad msg size.");
1304 return -EPROTO;
1305 }
1306
1307 *ring = msg.payload.state;
1308
1309 return 0;
1310 }
1311
vhost_set_vring_file(struct vhost_dev * dev,VhostUserRequest request,struct vhost_vring_file * file)1312 static int vhost_set_vring_file(struct vhost_dev *dev,
1313 VhostUserRequest request,
1314 struct vhost_vring_file *file)
1315 {
1316 int fds[VHOST_USER_MAX_RAM_SLOTS];
1317 size_t fd_num = 0;
1318 VhostUserMsg msg = {
1319 .hdr.request = request,
1320 .hdr.flags = VHOST_USER_VERSION,
1321 .payload.u64 = file->index & VHOST_USER_VRING_IDX_MASK,
1322 .hdr.size = sizeof(msg.payload.u64),
1323 };
1324
1325 if (file->fd > 0) {
1326 fds[fd_num++] = file->fd;
1327 } else {
1328 msg.payload.u64 |= VHOST_USER_VRING_NOFD_MASK;
1329 }
1330
1331 return vhost_user_write(dev, &msg, fds, fd_num);
1332 }
1333
vhost_user_set_vring_kick(struct vhost_dev * dev,struct vhost_vring_file * file)1334 static int vhost_user_set_vring_kick(struct vhost_dev *dev,
1335 struct vhost_vring_file *file)
1336 {
1337 return vhost_set_vring_file(dev, VHOST_USER_SET_VRING_KICK, file);
1338 }
1339
vhost_user_set_vring_call(struct vhost_dev * dev,struct vhost_vring_file * file)1340 static int vhost_user_set_vring_call(struct vhost_dev *dev,
1341 struct vhost_vring_file *file)
1342 {
1343 return vhost_set_vring_file(dev, VHOST_USER_SET_VRING_CALL, file);
1344 }
1345
vhost_user_set_vring_err(struct vhost_dev * dev,struct vhost_vring_file * file)1346 static int vhost_user_set_vring_err(struct vhost_dev *dev,
1347 struct vhost_vring_file *file)
1348 {
1349 return vhost_set_vring_file(dev, VHOST_USER_SET_VRING_ERR, file);
1350 }
1351
vhost_user_set_vring_addr(struct vhost_dev * dev,struct vhost_vring_addr * addr)1352 static int vhost_user_set_vring_addr(struct vhost_dev *dev,
1353 struct vhost_vring_addr *addr)
1354 {
1355 VhostUserMsg msg = {
1356 .hdr.request = VHOST_USER_SET_VRING_ADDR,
1357 .hdr.flags = VHOST_USER_VERSION,
1358 .payload.addr = *addr,
1359 .hdr.size = sizeof(msg.payload.addr),
1360 };
1361
1362 /*
1363 * wait for a reply if logging is enabled to make sure
1364 * backend is actually logging changes
1365 */
1366 bool wait_for_reply = addr->flags & (1 << VHOST_VRING_F_LOG);
1367
1368 return vhost_user_write_sync(dev, &msg, wait_for_reply);
1369 }
1370
vhost_user_set_u64(struct vhost_dev * dev,int request,uint64_t u64,bool wait_for_reply)1371 static int vhost_user_set_u64(struct vhost_dev *dev, int request, uint64_t u64,
1372 bool wait_for_reply)
1373 {
1374 VhostUserMsg msg = {
1375 .hdr.request = request,
1376 .hdr.flags = VHOST_USER_VERSION,
1377 .payload.u64 = u64,
1378 .hdr.size = sizeof(msg.payload.u64),
1379 };
1380
1381 return vhost_user_write_sync(dev, &msg, wait_for_reply);
1382 }
1383
vhost_user_set_status(struct vhost_dev * dev,uint8_t status)1384 static int vhost_user_set_status(struct vhost_dev *dev, uint8_t status)
1385 {
1386 return vhost_user_set_u64(dev, VHOST_USER_SET_STATUS, status, false);
1387 }
1388
vhost_user_get_status(struct vhost_dev * dev,uint8_t * status)1389 static int vhost_user_get_status(struct vhost_dev *dev, uint8_t *status)
1390 {
1391 uint64_t value;
1392 int ret;
1393
1394 ret = vhost_user_get_u64(dev, VHOST_USER_GET_STATUS, &value);
1395 if (ret < 0) {
1396 return ret;
1397 }
1398 *status = value;
1399
1400 return 0;
1401 }
1402
vhost_user_add_status(struct vhost_dev * dev,uint8_t status)1403 static int vhost_user_add_status(struct vhost_dev *dev, uint8_t status)
1404 {
1405 uint8_t s;
1406 int ret;
1407
1408 ret = vhost_user_get_status(dev, &s);
1409 if (ret < 0) {
1410 return ret;
1411 }
1412
1413 if ((s & status) == status) {
1414 return 0;
1415 }
1416 s |= status;
1417
1418 return vhost_user_set_status(dev, s);
1419 }
1420
vhost_user_set_features(struct vhost_dev * dev,uint64_t features)1421 static int vhost_user_set_features(struct vhost_dev *dev,
1422 uint64_t features)
1423 {
1424 /*
1425 * wait for a reply if logging is enabled to make sure
1426 * backend is actually logging changes
1427 */
1428 bool log_enabled = features & (0x1ULL << VHOST_F_LOG_ALL);
1429 int ret;
1430
1431 /*
1432 * We need to include any extra backend only feature bits that
1433 * might be needed by our device. Currently this includes the
1434 * VHOST_USER_F_PROTOCOL_FEATURES bit for enabling protocol
1435 * features.
1436 */
1437 ret = vhost_user_set_u64(dev, VHOST_USER_SET_FEATURES,
1438 features | dev->backend_features,
1439 log_enabled);
1440
1441 if (virtio_has_feature(dev->protocol_features,
1442 VHOST_USER_PROTOCOL_F_STATUS)) {
1443 if (!ret) {
1444 return vhost_user_add_status(dev, VIRTIO_CONFIG_S_FEATURES_OK);
1445 }
1446 }
1447
1448 return ret;
1449 }
1450
vhost_user_set_protocol_features(struct vhost_dev * dev,uint64_t features)1451 static int vhost_user_set_protocol_features(struct vhost_dev *dev,
1452 uint64_t features)
1453 {
1454 return vhost_user_set_u64(dev, VHOST_USER_SET_PROTOCOL_FEATURES, features,
1455 false);
1456 }
1457
vhost_user_set_owner(struct vhost_dev * dev)1458 static int vhost_user_set_owner(struct vhost_dev *dev)
1459 {
1460 VhostUserMsg msg = {
1461 .hdr.request = VHOST_USER_SET_OWNER,
1462 .hdr.flags = VHOST_USER_VERSION,
1463 };
1464
1465 return vhost_user_write(dev, &msg, NULL, 0);
1466 }
1467
vhost_user_get_max_memslots(struct vhost_dev * dev,uint64_t * max_memslots)1468 static int vhost_user_get_max_memslots(struct vhost_dev *dev,
1469 uint64_t *max_memslots)
1470 {
1471 uint64_t backend_max_memslots;
1472 int err;
1473
1474 err = vhost_user_get_u64(dev, VHOST_USER_GET_MAX_MEM_SLOTS,
1475 &backend_max_memslots);
1476 if (err < 0) {
1477 return err;
1478 }
1479
1480 *max_memslots = backend_max_memslots;
1481
1482 return 0;
1483 }
1484
vhost_user_reset_device(struct vhost_dev * dev)1485 static int vhost_user_reset_device(struct vhost_dev *dev)
1486 {
1487 VhostUserMsg msg = {
1488 .hdr.flags = VHOST_USER_VERSION,
1489 .hdr.request = VHOST_USER_RESET_DEVICE,
1490 };
1491
1492 /*
1493 * Historically, reset was not implemented so only reset devices
1494 * that are expecting it.
1495 */
1496 if (!virtio_has_feature(dev->protocol_features,
1497 VHOST_USER_PROTOCOL_F_RESET_DEVICE)) {
1498 return -ENOSYS;
1499 }
1500
1501 return vhost_user_write(dev, &msg, NULL, 0);
1502 }
1503
vhost_user_backend_handle_config_change(struct vhost_dev * dev)1504 static int vhost_user_backend_handle_config_change(struct vhost_dev *dev)
1505 {
1506 if (!dev->config_ops || !dev->config_ops->vhost_dev_config_notifier) {
1507 return -ENOSYS;
1508 }
1509
1510 return dev->config_ops->vhost_dev_config_notifier(dev);
1511 }
1512
1513 /*
1514 * Fetch or create the notifier for a given idx. Newly created
1515 * notifiers are added to the pointer array that tracks them.
1516 */
fetch_or_create_notifier(VhostUserState * u,int idx)1517 static VhostUserHostNotifier *fetch_or_create_notifier(VhostUserState *u,
1518 int idx)
1519 {
1520 VhostUserHostNotifier *n = NULL;
1521 if (idx >= u->notifiers->len) {
1522 g_ptr_array_set_size(u->notifiers, idx + 1);
1523 }
1524
1525 n = g_ptr_array_index(u->notifiers, idx);
1526 if (!n) {
1527 /*
1528 * In case notification arrive out-of-order,
1529 * make room for current index.
1530 */
1531 g_ptr_array_remove_index(u->notifiers, idx);
1532 n = g_new0(VhostUserHostNotifier, 1);
1533 n->idx = idx;
1534 g_ptr_array_insert(u->notifiers, idx, n);
1535 trace_vhost_user_create_notifier(idx, n);
1536 }
1537
1538 return n;
1539 }
1540
vhost_user_backend_handle_vring_host_notifier(struct vhost_dev * dev,VhostUserVringArea * area,int fd)1541 static int vhost_user_backend_handle_vring_host_notifier(struct vhost_dev *dev,
1542 VhostUserVringArea *area,
1543 int fd)
1544 {
1545 int queue_idx = area->u64 & VHOST_USER_VRING_IDX_MASK;
1546 size_t page_size = qemu_real_host_page_size();
1547 struct vhost_user *u = dev->opaque;
1548 VhostUserState *user = u->user;
1549 VirtIODevice *vdev = dev->vdev;
1550 VhostUserHostNotifier *n;
1551 void *addr;
1552 char *name;
1553
1554 if (!virtio_has_feature(dev->protocol_features,
1555 VHOST_USER_PROTOCOL_F_HOST_NOTIFIER) ||
1556 vdev == NULL || queue_idx >= virtio_get_num_queues(vdev)) {
1557 return -EINVAL;
1558 }
1559
1560 /*
1561 * Fetch notifier and invalidate any old data before setting up
1562 * new mapped address.
1563 */
1564 n = fetch_or_create_notifier(user, queue_idx);
1565 vhost_user_host_notifier_remove(n, vdev);
1566
1567 if (area->u64 & VHOST_USER_VRING_NOFD_MASK) {
1568 return 0;
1569 }
1570
1571 /* Sanity check. */
1572 if (area->size != page_size) {
1573 return -EINVAL;
1574 }
1575
1576 addr = mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_SHARED,
1577 fd, area->offset);
1578 if (addr == MAP_FAILED) {
1579 return -EFAULT;
1580 }
1581
1582 name = g_strdup_printf("vhost-user/host-notifier@%p mmaps[%d]",
1583 user, queue_idx);
1584 if (!n->mr.ram) { /* Don't init again after suspend. */
1585 memory_region_init_ram_device_ptr(&n->mr, OBJECT(vdev), name,
1586 page_size, addr);
1587 } else {
1588 n->mr.ram_block->host = addr;
1589 }
1590 g_free(name);
1591
1592 if (virtio_queue_set_host_notifier_mr(vdev, queue_idx, &n->mr, true)) {
1593 object_unparent(OBJECT(&n->mr));
1594 munmap(addr, page_size);
1595 return -ENXIO;
1596 }
1597
1598 n->addr = addr;
1599
1600 return 0;
1601 }
1602
1603 static int
vhost_user_backend_handle_shared_object_add(struct vhost_dev * dev,VhostUserShared * object)1604 vhost_user_backend_handle_shared_object_add(struct vhost_dev *dev,
1605 VhostUserShared *object)
1606 {
1607 QemuUUID uuid;
1608
1609 memcpy(uuid.data, object->uuid, sizeof(object->uuid));
1610 return virtio_add_vhost_device(&uuid, dev);
1611 }
1612
1613 static int
vhost_user_backend_handle_shared_object_remove(struct vhost_dev * dev,VhostUserShared * object)1614 vhost_user_backend_handle_shared_object_remove(struct vhost_dev *dev,
1615 VhostUserShared *object)
1616 {
1617 QemuUUID uuid;
1618
1619 memcpy(uuid.data, object->uuid, sizeof(object->uuid));
1620 switch (virtio_object_type(&uuid)) {
1621 case TYPE_VHOST_DEV:
1622 {
1623 struct vhost_dev *owner = virtio_lookup_vhost_device(&uuid);
1624 if (dev != owner) {
1625 /* Not allowed to remove non-owned entries */
1626 return 0;
1627 }
1628 break;
1629 }
1630 default:
1631 /* Not allowed to remove non-owned entries */
1632 return 0;
1633 }
1634
1635 return virtio_remove_resource(&uuid);
1636 }
1637
vhost_user_send_resp(QIOChannel * ioc,VhostUserHeader * hdr,VhostUserPayload * payload,Error ** errp)1638 static bool vhost_user_send_resp(QIOChannel *ioc, VhostUserHeader *hdr,
1639 VhostUserPayload *payload, Error **errp)
1640 {
1641 struct iovec iov[] = {
1642 { .iov_base = hdr, .iov_len = VHOST_USER_HDR_SIZE },
1643 { .iov_base = payload, .iov_len = hdr->size },
1644 };
1645
1646 hdr->flags &= ~VHOST_USER_NEED_REPLY_MASK;
1647 hdr->flags |= VHOST_USER_REPLY_MASK;
1648
1649 return !qio_channel_writev_all(ioc, iov, ARRAY_SIZE(iov), errp);
1650 }
1651
1652 static bool
vhost_user_backend_send_dmabuf_fd(QIOChannel * ioc,VhostUserHeader * hdr,VhostUserPayload * payload,Error ** errp)1653 vhost_user_backend_send_dmabuf_fd(QIOChannel *ioc, VhostUserHeader *hdr,
1654 VhostUserPayload *payload, Error **errp)
1655 {
1656 hdr->size = sizeof(payload->u64);
1657 return vhost_user_send_resp(ioc, hdr, payload, errp);
1658 }
1659
vhost_user_get_shared_object(struct vhost_dev * dev,unsigned char * uuid,int * dmabuf_fd)1660 int vhost_user_get_shared_object(struct vhost_dev *dev, unsigned char *uuid,
1661 int *dmabuf_fd)
1662 {
1663 struct vhost_user *u = dev->opaque;
1664 CharBackend *chr = u->user->chr;
1665 int ret;
1666 VhostUserMsg msg = {
1667 .hdr.request = VHOST_USER_GET_SHARED_OBJECT,
1668 .hdr.flags = VHOST_USER_VERSION,
1669 };
1670 memcpy(msg.payload.object.uuid, uuid, sizeof(msg.payload.object.uuid));
1671
1672 ret = vhost_user_write(dev, &msg, NULL, 0);
1673 if (ret < 0) {
1674 return ret;
1675 }
1676
1677 ret = vhost_user_read(dev, &msg);
1678 if (ret < 0) {
1679 return ret;
1680 }
1681
1682 if (msg.hdr.request != VHOST_USER_GET_SHARED_OBJECT) {
1683 error_report("Received unexpected msg type. "
1684 "Expected %d received %d",
1685 VHOST_USER_GET_SHARED_OBJECT, msg.hdr.request);
1686 return -EPROTO;
1687 }
1688
1689 *dmabuf_fd = qemu_chr_fe_get_msgfd(chr);
1690 if (*dmabuf_fd < 0) {
1691 error_report("Failed to get dmabuf fd");
1692 return -EIO;
1693 }
1694
1695 return 0;
1696 }
1697
1698 static int
vhost_user_backend_handle_shared_object_lookup(struct vhost_user * u,QIOChannel * ioc,VhostUserHeader * hdr,VhostUserPayload * payload)1699 vhost_user_backend_handle_shared_object_lookup(struct vhost_user *u,
1700 QIOChannel *ioc,
1701 VhostUserHeader *hdr,
1702 VhostUserPayload *payload)
1703 {
1704 QemuUUID uuid;
1705 CharBackend *chr = u->user->chr;
1706 Error *local_err = NULL;
1707 int dmabuf_fd = -1;
1708 int fd_num = 0;
1709
1710 memcpy(uuid.data, payload->object.uuid, sizeof(payload->object.uuid));
1711
1712 payload->u64 = 0;
1713 switch (virtio_object_type(&uuid)) {
1714 case TYPE_DMABUF:
1715 dmabuf_fd = virtio_lookup_dmabuf(&uuid);
1716 break;
1717 case TYPE_VHOST_DEV:
1718 {
1719 struct vhost_dev *dev = virtio_lookup_vhost_device(&uuid);
1720 if (dev == NULL) {
1721 payload->u64 = -EINVAL;
1722 break;
1723 }
1724 int ret = vhost_user_get_shared_object(dev, uuid.data, &dmabuf_fd);
1725 if (ret < 0) {
1726 payload->u64 = ret;
1727 }
1728 break;
1729 }
1730 case TYPE_INVALID:
1731 payload->u64 = -EINVAL;
1732 break;
1733 }
1734
1735 if (dmabuf_fd != -1) {
1736 fd_num++;
1737 }
1738
1739 if (qemu_chr_fe_set_msgfds(chr, &dmabuf_fd, fd_num) < 0) {
1740 error_report("Failed to set msg fds.");
1741 payload->u64 = -EINVAL;
1742 }
1743
1744 if (!vhost_user_backend_send_dmabuf_fd(ioc, hdr, payload, &local_err)) {
1745 error_report_err(local_err);
1746 return -EINVAL;
1747 }
1748
1749 return 0;
1750 }
1751
close_backend_channel(struct vhost_user * u)1752 static void close_backend_channel(struct vhost_user *u)
1753 {
1754 g_source_destroy(u->backend_src);
1755 g_source_unref(u->backend_src);
1756 u->backend_src = NULL;
1757 object_unref(OBJECT(u->backend_ioc));
1758 u->backend_ioc = NULL;
1759 }
1760
backend_read(QIOChannel * ioc,GIOCondition condition,gpointer opaque)1761 static gboolean backend_read(QIOChannel *ioc, GIOCondition condition,
1762 gpointer opaque)
1763 {
1764 struct vhost_dev *dev = opaque;
1765 struct vhost_user *u = dev->opaque;
1766 VhostUserHeader hdr = { 0, };
1767 VhostUserPayload payload = { 0, };
1768 Error *local_err = NULL;
1769 gboolean rc = G_SOURCE_CONTINUE;
1770 int ret = 0;
1771 struct iovec iov;
1772 g_autofree int *fd = NULL;
1773 size_t fdsize = 0;
1774 int i;
1775
1776 /* Read header */
1777 iov.iov_base = &hdr;
1778 iov.iov_len = VHOST_USER_HDR_SIZE;
1779
1780 if (qio_channel_readv_full_all(ioc, &iov, 1, &fd, &fdsize, &local_err)) {
1781 error_report_err(local_err);
1782 goto err;
1783 }
1784
1785 if (hdr.size > VHOST_USER_PAYLOAD_SIZE) {
1786 error_report("Failed to read msg header."
1787 " Size %d exceeds the maximum %zu.", hdr.size,
1788 VHOST_USER_PAYLOAD_SIZE);
1789 goto err;
1790 }
1791
1792 /* Read payload */
1793 if (qio_channel_read_all(ioc, (char *) &payload, hdr.size, &local_err)) {
1794 error_report_err(local_err);
1795 goto err;
1796 }
1797
1798 switch (hdr.request) {
1799 case VHOST_USER_BACKEND_IOTLB_MSG:
1800 ret = vhost_backend_handle_iotlb_msg(dev, &payload.iotlb);
1801 break;
1802 case VHOST_USER_BACKEND_CONFIG_CHANGE_MSG:
1803 ret = vhost_user_backend_handle_config_change(dev);
1804 break;
1805 case VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG:
1806 ret = vhost_user_backend_handle_vring_host_notifier(dev, &payload.area,
1807 fd ? fd[0] : -1);
1808 break;
1809 case VHOST_USER_BACKEND_SHARED_OBJECT_ADD:
1810 ret = vhost_user_backend_handle_shared_object_add(dev, &payload.object);
1811 break;
1812 case VHOST_USER_BACKEND_SHARED_OBJECT_REMOVE:
1813 ret = vhost_user_backend_handle_shared_object_remove(dev,
1814 &payload.object);
1815 break;
1816 case VHOST_USER_BACKEND_SHARED_OBJECT_LOOKUP:
1817 ret = vhost_user_backend_handle_shared_object_lookup(dev->opaque, ioc,
1818 &hdr, &payload);
1819 break;
1820 default:
1821 error_report("Received unexpected msg type: %d.", hdr.request);
1822 ret = -EINVAL;
1823 }
1824
1825 /*
1826 * REPLY_ACK feature handling. Other reply types has to be managed
1827 * directly in their request handlers.
1828 */
1829 if (hdr.flags & VHOST_USER_NEED_REPLY_MASK) {
1830 payload.u64 = !!ret;
1831 hdr.size = sizeof(payload.u64);
1832
1833 if (!vhost_user_send_resp(ioc, &hdr, &payload, &local_err)) {
1834 error_report_err(local_err);
1835 goto err;
1836 }
1837 }
1838
1839 goto fdcleanup;
1840
1841 err:
1842 close_backend_channel(u);
1843 rc = G_SOURCE_REMOVE;
1844
1845 fdcleanup:
1846 if (fd) {
1847 for (i = 0; i < fdsize; i++) {
1848 close(fd[i]);
1849 }
1850 }
1851 return rc;
1852 }
1853
vhost_setup_backend_channel(struct vhost_dev * dev)1854 static int vhost_setup_backend_channel(struct vhost_dev *dev)
1855 {
1856 VhostUserMsg msg = {
1857 .hdr.request = VHOST_USER_SET_BACKEND_REQ_FD,
1858 .hdr.flags = VHOST_USER_VERSION,
1859 };
1860 struct vhost_user *u = dev->opaque;
1861 int sv[2], ret = 0;
1862 bool reply_supported = virtio_has_feature(dev->protocol_features,
1863 VHOST_USER_PROTOCOL_F_REPLY_ACK);
1864 Error *local_err = NULL;
1865 QIOChannel *ioc;
1866
1867 if (!virtio_has_feature(dev->protocol_features,
1868 VHOST_USER_PROTOCOL_F_BACKEND_REQ)) {
1869 return 0;
1870 }
1871
1872 if (qemu_socketpair(PF_UNIX, SOCK_STREAM, 0, sv) == -1) {
1873 int saved_errno = errno;
1874 error_report("socketpair() failed");
1875 return -saved_errno;
1876 }
1877
1878 ioc = QIO_CHANNEL(qio_channel_socket_new_fd(sv[0], &local_err));
1879 if (!ioc) {
1880 error_report_err(local_err);
1881 return -ECONNREFUSED;
1882 }
1883 u->backend_ioc = ioc;
1884 u->backend_src = qio_channel_add_watch_source(u->backend_ioc,
1885 G_IO_IN | G_IO_HUP,
1886 backend_read, dev, NULL, NULL);
1887
1888 if (reply_supported) {
1889 msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
1890 }
1891
1892 ret = vhost_user_write(dev, &msg, &sv[1], 1);
1893 if (ret) {
1894 goto out;
1895 }
1896
1897 if (reply_supported) {
1898 ret = process_message_reply(dev, &msg);
1899 }
1900
1901 out:
1902 close(sv[1]);
1903 if (ret) {
1904 close_backend_channel(u);
1905 }
1906
1907 return ret;
1908 }
1909
1910 #ifdef CONFIG_LINUX
1911 /*
1912 * Called back from the postcopy fault thread when a fault is received on our
1913 * ufd.
1914 * TODO: This is Linux specific
1915 */
vhost_user_postcopy_fault_handler(struct PostCopyFD * pcfd,void * ufd)1916 static int vhost_user_postcopy_fault_handler(struct PostCopyFD *pcfd,
1917 void *ufd)
1918 {
1919 struct vhost_dev *dev = pcfd->data;
1920 struct vhost_user *u = dev->opaque;
1921 struct uffd_msg *msg = ufd;
1922 uint64_t faultaddr = msg->arg.pagefault.address;
1923 RAMBlock *rb = NULL;
1924 uint64_t rb_offset;
1925 int i;
1926
1927 trace_vhost_user_postcopy_fault_handler(pcfd->idstr, faultaddr,
1928 dev->mem->nregions);
1929 for (i = 0; i < MIN(dev->mem->nregions, u->region_rb_len); i++) {
1930 trace_vhost_user_postcopy_fault_handler_loop(i,
1931 u->postcopy_client_bases[i], dev->mem->regions[i].memory_size);
1932 if (faultaddr >= u->postcopy_client_bases[i]) {
1933 /* Ofset of the fault address in the vhost region */
1934 uint64_t region_offset = faultaddr - u->postcopy_client_bases[i];
1935 if (region_offset < dev->mem->regions[i].memory_size) {
1936 rb_offset = region_offset + u->region_rb_offset[i];
1937 trace_vhost_user_postcopy_fault_handler_found(i,
1938 region_offset, rb_offset);
1939 rb = u->region_rb[i];
1940 return postcopy_request_shared_page(pcfd, rb, faultaddr,
1941 rb_offset);
1942 }
1943 }
1944 }
1945 error_report("%s: Failed to find region for fault %" PRIx64,
1946 __func__, faultaddr);
1947 return -1;
1948 }
1949
vhost_user_postcopy_waker(struct PostCopyFD * pcfd,RAMBlock * rb,uint64_t offset)1950 static int vhost_user_postcopy_waker(struct PostCopyFD *pcfd, RAMBlock *rb,
1951 uint64_t offset)
1952 {
1953 struct vhost_dev *dev = pcfd->data;
1954 struct vhost_user *u = dev->opaque;
1955 int i;
1956
1957 trace_vhost_user_postcopy_waker(qemu_ram_get_idstr(rb), offset);
1958
1959 if (!u) {
1960 return 0;
1961 }
1962 /* Translate the offset into an address in the clients address space */
1963 for (i = 0; i < MIN(dev->mem->nregions, u->region_rb_len); i++) {
1964 if (u->region_rb[i] == rb &&
1965 offset >= u->region_rb_offset[i] &&
1966 offset < (u->region_rb_offset[i] +
1967 dev->mem->regions[i].memory_size)) {
1968 uint64_t client_addr = (offset - u->region_rb_offset[i]) +
1969 u->postcopy_client_bases[i];
1970 trace_vhost_user_postcopy_waker_found(client_addr);
1971 return postcopy_wake_shared(pcfd, client_addr, rb);
1972 }
1973 }
1974
1975 trace_vhost_user_postcopy_waker_nomatch(qemu_ram_get_idstr(rb), offset);
1976 return 0;
1977 }
1978 #endif
1979
1980 /*
1981 * Called at the start of an inbound postcopy on reception of the
1982 * 'advise' command.
1983 */
vhost_user_postcopy_advise(struct vhost_dev * dev,Error ** errp)1984 static int vhost_user_postcopy_advise(struct vhost_dev *dev, Error **errp)
1985 {
1986 #ifdef CONFIG_LINUX
1987 struct vhost_user *u = dev->opaque;
1988 CharBackend *chr = u->user->chr;
1989 int ufd;
1990 int ret;
1991 VhostUserMsg msg = {
1992 .hdr.request = VHOST_USER_POSTCOPY_ADVISE,
1993 .hdr.flags = VHOST_USER_VERSION,
1994 };
1995
1996 ret = vhost_user_write(dev, &msg, NULL, 0);
1997 if (ret < 0) {
1998 error_setg(errp, "Failed to send postcopy_advise to vhost");
1999 return ret;
2000 }
2001
2002 ret = vhost_user_read(dev, &msg);
2003 if (ret < 0) {
2004 error_setg(errp, "Failed to get postcopy_advise reply from vhost");
2005 return ret;
2006 }
2007
2008 if (msg.hdr.request != VHOST_USER_POSTCOPY_ADVISE) {
2009 error_setg(errp, "Unexpected msg type. Expected %d received %d",
2010 VHOST_USER_POSTCOPY_ADVISE, msg.hdr.request);
2011 return -EPROTO;
2012 }
2013
2014 if (msg.hdr.size) {
2015 error_setg(errp, "Received bad msg size.");
2016 return -EPROTO;
2017 }
2018 ufd = qemu_chr_fe_get_msgfd(chr);
2019 if (ufd < 0) {
2020 error_setg(errp, "%s: Failed to get ufd", __func__);
2021 return -EIO;
2022 }
2023 qemu_socket_set_nonblock(ufd);
2024
2025 /* register ufd with userfault thread */
2026 u->postcopy_fd.fd = ufd;
2027 u->postcopy_fd.data = dev;
2028 u->postcopy_fd.handler = vhost_user_postcopy_fault_handler;
2029 u->postcopy_fd.waker = vhost_user_postcopy_waker;
2030 u->postcopy_fd.idstr = "vhost-user"; /* Need to find unique name */
2031 postcopy_register_shared_ufd(&u->postcopy_fd);
2032 return 0;
2033 #else
2034 error_setg(errp, "Postcopy not supported on non-Linux systems");
2035 return -ENOSYS;
2036 #endif
2037 }
2038
2039 /*
2040 * Called at the switch to postcopy on reception of the 'listen' command.
2041 */
vhost_user_postcopy_listen(struct vhost_dev * dev,Error ** errp)2042 static int vhost_user_postcopy_listen(struct vhost_dev *dev, Error **errp)
2043 {
2044 struct vhost_user *u = dev->opaque;
2045 int ret;
2046 VhostUserMsg msg = {
2047 .hdr.request = VHOST_USER_POSTCOPY_LISTEN,
2048 .hdr.flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK,
2049 };
2050 u->postcopy_listen = true;
2051
2052 trace_vhost_user_postcopy_listen();
2053
2054 ret = vhost_user_write(dev, &msg, NULL, 0);
2055 if (ret < 0) {
2056 error_setg(errp, "Failed to send postcopy_listen to vhost");
2057 return ret;
2058 }
2059
2060 ret = process_message_reply(dev, &msg);
2061 if (ret) {
2062 error_setg(errp, "Failed to receive reply to postcopy_listen");
2063 return ret;
2064 }
2065
2066 return 0;
2067 }
2068
2069 /*
2070 * Called at the end of postcopy
2071 */
vhost_user_postcopy_end(struct vhost_dev * dev,Error ** errp)2072 static int vhost_user_postcopy_end(struct vhost_dev *dev, Error **errp)
2073 {
2074 VhostUserMsg msg = {
2075 .hdr.request = VHOST_USER_POSTCOPY_END,
2076 .hdr.flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK,
2077 };
2078 int ret;
2079 struct vhost_user *u = dev->opaque;
2080
2081 trace_vhost_user_postcopy_end_entry();
2082
2083 ret = vhost_user_write(dev, &msg, NULL, 0);
2084 if (ret < 0) {
2085 error_setg(errp, "Failed to send postcopy_end to vhost");
2086 return ret;
2087 }
2088
2089 ret = process_message_reply(dev, &msg);
2090 if (ret) {
2091 error_setg(errp, "Failed to receive reply to postcopy_end");
2092 return ret;
2093 }
2094 postcopy_unregister_shared_ufd(&u->postcopy_fd);
2095 close(u->postcopy_fd.fd);
2096 u->postcopy_fd.handler = NULL;
2097
2098 trace_vhost_user_postcopy_end_exit();
2099
2100 return 0;
2101 }
2102
vhost_user_postcopy_notifier(NotifierWithReturn * notifier,void * opaque,Error ** errp)2103 static int vhost_user_postcopy_notifier(NotifierWithReturn *notifier,
2104 void *opaque, Error **errp)
2105 {
2106 struct PostcopyNotifyData *pnd = opaque;
2107 struct vhost_user *u = container_of(notifier, struct vhost_user,
2108 postcopy_notifier);
2109 struct vhost_dev *dev = u->dev;
2110
2111 switch (pnd->reason) {
2112 case POSTCOPY_NOTIFY_PROBE:
2113 if (!virtio_has_feature(dev->protocol_features,
2114 VHOST_USER_PROTOCOL_F_PAGEFAULT)) {
2115 /* TODO: Get the device name into this error somehow */
2116 error_setg(errp,
2117 "vhost-user backend not capable of postcopy");
2118 return -ENOENT;
2119 }
2120 break;
2121
2122 case POSTCOPY_NOTIFY_INBOUND_ADVISE:
2123 return vhost_user_postcopy_advise(dev, errp);
2124
2125 case POSTCOPY_NOTIFY_INBOUND_LISTEN:
2126 return vhost_user_postcopy_listen(dev, errp);
2127
2128 case POSTCOPY_NOTIFY_INBOUND_END:
2129 return vhost_user_postcopy_end(dev, errp);
2130
2131 default:
2132 /* We ignore notifications we don't know */
2133 break;
2134 }
2135
2136 return 0;
2137 }
2138
vhost_user_backend_init(struct vhost_dev * dev,void * opaque,Error ** errp)2139 static int vhost_user_backend_init(struct vhost_dev *dev, void *opaque,
2140 Error **errp)
2141 {
2142 uint64_t features, ram_slots;
2143 struct vhost_user *u;
2144 VhostUserState *vus = (VhostUserState *) opaque;
2145 int err;
2146
2147 assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
2148
2149 u = g_new0(struct vhost_user, 1);
2150 u->user = vus;
2151 u->dev = dev;
2152 dev->opaque = u;
2153
2154 err = vhost_user_get_features(dev, &features);
2155 if (err < 0) {
2156 error_setg_errno(errp, -err, "vhost_backend_init failed");
2157 return err;
2158 }
2159
2160 if (virtio_has_feature(features, VHOST_USER_F_PROTOCOL_FEATURES)) {
2161 bool supports_f_config = vus->supports_config ||
2162 (dev->config_ops && dev->config_ops->vhost_dev_config_notifier);
2163 uint64_t protocol_features;
2164
2165 dev->backend_features |= 1ULL << VHOST_USER_F_PROTOCOL_FEATURES;
2166
2167 err = vhost_user_get_u64(dev, VHOST_USER_GET_PROTOCOL_FEATURES,
2168 &protocol_features);
2169 if (err < 0) {
2170 error_setg_errno(errp, EPROTO, "vhost_backend_init failed");
2171 return -EPROTO;
2172 }
2173
2174 /*
2175 * We will use all the protocol features we support - although
2176 * we suppress F_CONFIG if we know QEMUs internal code can not support
2177 * it.
2178 */
2179 protocol_features &= VHOST_USER_PROTOCOL_FEATURE_MASK;
2180
2181 if (supports_f_config) {
2182 if (!virtio_has_feature(protocol_features,
2183 VHOST_USER_PROTOCOL_F_CONFIG)) {
2184 error_setg(errp, "vhost-user device expecting "
2185 "VHOST_USER_PROTOCOL_F_CONFIG but the vhost-user backend does "
2186 "not support it.");
2187 return -EPROTO;
2188 }
2189 } else {
2190 if (virtio_has_feature(protocol_features,
2191 VHOST_USER_PROTOCOL_F_CONFIG)) {
2192 warn_report("vhost-user backend supports "
2193 "VHOST_USER_PROTOCOL_F_CONFIG but QEMU does not.");
2194 protocol_features &= ~(1ULL << VHOST_USER_PROTOCOL_F_CONFIG);
2195 }
2196 }
2197
2198 /* final set of protocol features */
2199 dev->protocol_features = protocol_features;
2200 err = vhost_user_set_protocol_features(dev, dev->protocol_features);
2201 if (err < 0) {
2202 error_setg_errno(errp, EPROTO, "vhost_backend_init failed");
2203 return -EPROTO;
2204 }
2205
2206 /* query the max queues we support if backend supports Multiple Queue */
2207 if (dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_MQ)) {
2208 err = vhost_user_get_u64(dev, VHOST_USER_GET_QUEUE_NUM,
2209 &dev->max_queues);
2210 if (err < 0) {
2211 error_setg_errno(errp, EPROTO, "vhost_backend_init failed");
2212 return -EPROTO;
2213 }
2214 } else {
2215 dev->max_queues = 1;
2216 }
2217
2218 if (dev->num_queues && dev->max_queues < dev->num_queues) {
2219 error_setg(errp, "The maximum number of queues supported by the "
2220 "backend is %" PRIu64, dev->max_queues);
2221 return -EINVAL;
2222 }
2223
2224 if (virtio_has_feature(features, VIRTIO_F_IOMMU_PLATFORM) &&
2225 !(virtio_has_feature(dev->protocol_features,
2226 VHOST_USER_PROTOCOL_F_BACKEND_REQ) &&
2227 virtio_has_feature(dev->protocol_features,
2228 VHOST_USER_PROTOCOL_F_REPLY_ACK))) {
2229 error_setg(errp, "IOMMU support requires reply-ack and "
2230 "backend-req protocol features.");
2231 return -EINVAL;
2232 }
2233
2234 /* get max memory regions if backend supports configurable RAM slots */
2235 if (!virtio_has_feature(dev->protocol_features,
2236 VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS)) {
2237 u->user->memory_slots = VHOST_MEMORY_BASELINE_NREGIONS;
2238 } else {
2239 err = vhost_user_get_max_memslots(dev, &ram_slots);
2240 if (err < 0) {
2241 error_setg_errno(errp, EPROTO, "vhost_backend_init failed");
2242 return -EPROTO;
2243 }
2244
2245 if (ram_slots < u->user->memory_slots) {
2246 error_setg(errp, "The backend specified a max ram slots limit "
2247 "of %" PRIu64", when the prior validated limit was "
2248 "%d. This limit should never decrease.", ram_slots,
2249 u->user->memory_slots);
2250 return -EINVAL;
2251 }
2252
2253 u->user->memory_slots = MIN(ram_slots, VHOST_USER_MAX_RAM_SLOTS);
2254 }
2255 }
2256
2257 if (dev->migration_blocker == NULL &&
2258 !virtio_has_feature(dev->protocol_features,
2259 VHOST_USER_PROTOCOL_F_LOG_SHMFD)) {
2260 error_setg(&dev->migration_blocker,
2261 "Migration disabled: vhost-user backend lacks "
2262 "VHOST_USER_PROTOCOL_F_LOG_SHMFD feature.");
2263 }
2264
2265 if (dev->vq_index == 0) {
2266 err = vhost_setup_backend_channel(dev);
2267 if (err < 0) {
2268 error_setg_errno(errp, EPROTO, "vhost_backend_init failed");
2269 return -EPROTO;
2270 }
2271 }
2272
2273 u->postcopy_notifier.notify = vhost_user_postcopy_notifier;
2274 postcopy_add_notifier(&u->postcopy_notifier);
2275
2276 return 0;
2277 }
2278
vhost_user_backend_cleanup(struct vhost_dev * dev)2279 static int vhost_user_backend_cleanup(struct vhost_dev *dev)
2280 {
2281 struct vhost_user *u;
2282
2283 assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
2284
2285 u = dev->opaque;
2286 if (u->postcopy_notifier.notify) {
2287 postcopy_remove_notifier(&u->postcopy_notifier);
2288 u->postcopy_notifier.notify = NULL;
2289 }
2290 u->postcopy_listen = false;
2291 if (u->postcopy_fd.handler) {
2292 postcopy_unregister_shared_ufd(&u->postcopy_fd);
2293 close(u->postcopy_fd.fd);
2294 u->postcopy_fd.handler = NULL;
2295 }
2296 if (u->backend_ioc) {
2297 close_backend_channel(u);
2298 }
2299 g_free(u->region_rb);
2300 u->region_rb = NULL;
2301 g_free(u->region_rb_offset);
2302 u->region_rb_offset = NULL;
2303 u->region_rb_len = 0;
2304 g_free(u);
2305 dev->opaque = 0;
2306
2307 return 0;
2308 }
2309
vhost_user_get_vq_index(struct vhost_dev * dev,int idx)2310 static int vhost_user_get_vq_index(struct vhost_dev *dev, int idx)
2311 {
2312 assert(idx >= dev->vq_index && idx < dev->vq_index + dev->nvqs);
2313
2314 return idx;
2315 }
2316
vhost_user_memslots_limit(struct vhost_dev * dev)2317 static int vhost_user_memslots_limit(struct vhost_dev *dev)
2318 {
2319 struct vhost_user *u = dev->opaque;
2320
2321 return u->user->memory_slots;
2322 }
2323
vhost_user_requires_shm_log(struct vhost_dev * dev)2324 static bool vhost_user_requires_shm_log(struct vhost_dev *dev)
2325 {
2326 assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
2327
2328 return virtio_has_feature(dev->protocol_features,
2329 VHOST_USER_PROTOCOL_F_LOG_SHMFD);
2330 }
2331
vhost_user_migration_done(struct vhost_dev * dev,char * mac_addr)2332 static int vhost_user_migration_done(struct vhost_dev *dev, char* mac_addr)
2333 {
2334 VhostUserMsg msg = { };
2335
2336 assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
2337
2338 /* If guest supports GUEST_ANNOUNCE do nothing */
2339 if (virtio_has_feature(dev->acked_features, VIRTIO_NET_F_GUEST_ANNOUNCE)) {
2340 return 0;
2341 }
2342
2343 /* if backend supports VHOST_USER_PROTOCOL_F_RARP ask it to send the RARP */
2344 if (virtio_has_feature(dev->protocol_features,
2345 VHOST_USER_PROTOCOL_F_RARP)) {
2346 msg.hdr.request = VHOST_USER_SEND_RARP;
2347 msg.hdr.flags = VHOST_USER_VERSION;
2348 memcpy((char *)&msg.payload.u64, mac_addr, 6);
2349 msg.hdr.size = sizeof(msg.payload.u64);
2350
2351 return vhost_user_write(dev, &msg, NULL, 0);
2352 }
2353 return -ENOTSUP;
2354 }
2355
vhost_user_net_set_mtu(struct vhost_dev * dev,uint16_t mtu)2356 static int vhost_user_net_set_mtu(struct vhost_dev *dev, uint16_t mtu)
2357 {
2358 VhostUserMsg msg;
2359 bool reply_supported = virtio_has_feature(dev->protocol_features,
2360 VHOST_USER_PROTOCOL_F_REPLY_ACK);
2361 int ret;
2362
2363 if (!(dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_NET_MTU))) {
2364 return 0;
2365 }
2366
2367 msg.hdr.request = VHOST_USER_NET_SET_MTU;
2368 msg.payload.u64 = mtu;
2369 msg.hdr.size = sizeof(msg.payload.u64);
2370 msg.hdr.flags = VHOST_USER_VERSION;
2371 if (reply_supported) {
2372 msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
2373 }
2374
2375 ret = vhost_user_write(dev, &msg, NULL, 0);
2376 if (ret < 0) {
2377 return ret;
2378 }
2379
2380 /* If reply_ack supported, backend has to ack specified MTU is valid */
2381 if (reply_supported) {
2382 return process_message_reply(dev, &msg);
2383 }
2384
2385 return 0;
2386 }
2387
vhost_user_send_device_iotlb_msg(struct vhost_dev * dev,struct vhost_iotlb_msg * imsg)2388 static int vhost_user_send_device_iotlb_msg(struct vhost_dev *dev,
2389 struct vhost_iotlb_msg *imsg)
2390 {
2391 int ret;
2392 VhostUserMsg msg = {
2393 .hdr.request = VHOST_USER_IOTLB_MSG,
2394 .hdr.size = sizeof(msg.payload.iotlb),
2395 .hdr.flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK,
2396 .payload.iotlb = *imsg,
2397 };
2398
2399 ret = vhost_user_write(dev, &msg, NULL, 0);
2400 if (ret < 0) {
2401 return ret;
2402 }
2403
2404 return process_message_reply(dev, &msg);
2405 }
2406
2407
vhost_user_set_iotlb_callback(struct vhost_dev * dev,int enabled)2408 static void vhost_user_set_iotlb_callback(struct vhost_dev *dev, int enabled)
2409 {
2410 /* No-op as the receive channel is not dedicated to IOTLB messages. */
2411 }
2412
vhost_user_get_config(struct vhost_dev * dev,uint8_t * config,uint32_t config_len,Error ** errp)2413 static int vhost_user_get_config(struct vhost_dev *dev, uint8_t *config,
2414 uint32_t config_len, Error **errp)
2415 {
2416 int ret;
2417 VhostUserMsg msg = {
2418 .hdr.request = VHOST_USER_GET_CONFIG,
2419 .hdr.flags = VHOST_USER_VERSION,
2420 .hdr.size = VHOST_USER_CONFIG_HDR_SIZE + config_len,
2421 };
2422
2423 if (!virtio_has_feature(dev->protocol_features,
2424 VHOST_USER_PROTOCOL_F_CONFIG)) {
2425 error_setg(errp, "VHOST_USER_PROTOCOL_F_CONFIG not supported");
2426 return -EINVAL;
2427 }
2428
2429 assert(config_len <= VHOST_USER_MAX_CONFIG_SIZE);
2430
2431 msg.payload.config.offset = 0;
2432 msg.payload.config.size = config_len;
2433 ret = vhost_user_write(dev, &msg, NULL, 0);
2434 if (ret < 0) {
2435 error_setg_errno(errp, -ret, "vhost_get_config failed");
2436 return ret;
2437 }
2438
2439 ret = vhost_user_read(dev, &msg);
2440 if (ret < 0) {
2441 error_setg_errno(errp, -ret, "vhost_get_config failed");
2442 return ret;
2443 }
2444
2445 if (msg.hdr.request != VHOST_USER_GET_CONFIG) {
2446 error_setg(errp,
2447 "Received unexpected msg type. Expected %d received %d",
2448 VHOST_USER_GET_CONFIG, msg.hdr.request);
2449 return -EPROTO;
2450 }
2451
2452 if (msg.hdr.size != VHOST_USER_CONFIG_HDR_SIZE + config_len) {
2453 error_setg(errp, "Received bad msg size.");
2454 return -EPROTO;
2455 }
2456
2457 memcpy(config, msg.payload.config.region, config_len);
2458
2459 return 0;
2460 }
2461
vhost_user_set_config(struct vhost_dev * dev,const uint8_t * data,uint32_t offset,uint32_t size,uint32_t flags)2462 static int vhost_user_set_config(struct vhost_dev *dev, const uint8_t *data,
2463 uint32_t offset, uint32_t size, uint32_t flags)
2464 {
2465 int ret;
2466 uint8_t *p;
2467 bool reply_supported = virtio_has_feature(dev->protocol_features,
2468 VHOST_USER_PROTOCOL_F_REPLY_ACK);
2469
2470 VhostUserMsg msg = {
2471 .hdr.request = VHOST_USER_SET_CONFIG,
2472 .hdr.flags = VHOST_USER_VERSION,
2473 .hdr.size = VHOST_USER_CONFIG_HDR_SIZE + size,
2474 };
2475
2476 if (!virtio_has_feature(dev->protocol_features,
2477 VHOST_USER_PROTOCOL_F_CONFIG)) {
2478 return -ENOTSUP;
2479 }
2480
2481 if (reply_supported) {
2482 msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
2483 }
2484
2485 if (size > VHOST_USER_MAX_CONFIG_SIZE) {
2486 return -EINVAL;
2487 }
2488
2489 msg.payload.config.offset = offset,
2490 msg.payload.config.size = size,
2491 msg.payload.config.flags = flags,
2492 p = msg.payload.config.region;
2493 memcpy(p, data, size);
2494
2495 ret = vhost_user_write(dev, &msg, NULL, 0);
2496 if (ret < 0) {
2497 return ret;
2498 }
2499
2500 if (reply_supported) {
2501 return process_message_reply(dev, &msg);
2502 }
2503
2504 return 0;
2505 }
2506
vhost_user_crypto_create_session(struct vhost_dev * dev,void * session_info,uint64_t * session_id)2507 static int vhost_user_crypto_create_session(struct vhost_dev *dev,
2508 void *session_info,
2509 uint64_t *session_id)
2510 {
2511 int ret;
2512 bool crypto_session = virtio_has_feature(dev->protocol_features,
2513 VHOST_USER_PROTOCOL_F_CRYPTO_SESSION);
2514 CryptoDevBackendSessionInfo *backend_info = session_info;
2515 VhostUserMsg msg = {
2516 .hdr.request = VHOST_USER_CREATE_CRYPTO_SESSION,
2517 .hdr.flags = VHOST_USER_VERSION,
2518 .hdr.size = sizeof(msg.payload.session),
2519 };
2520
2521 assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
2522
2523 if (!crypto_session) {
2524 error_report("vhost-user trying to send unhandled ioctl");
2525 return -ENOTSUP;
2526 }
2527
2528 if (backend_info->op_code == VIRTIO_CRYPTO_AKCIPHER_CREATE_SESSION) {
2529 CryptoDevBackendAsymSessionInfo *sess = &backend_info->u.asym_sess_info;
2530 size_t keylen;
2531
2532 memcpy(&msg.payload.session.u.asym.session_setup_data, sess,
2533 sizeof(CryptoDevBackendAsymSessionInfo));
2534 if (sess->keylen) {
2535 keylen = sizeof(msg.payload.session.u.asym.key);
2536 if (sess->keylen > keylen) {
2537 error_report("Unsupported asymmetric key size");
2538 return -ENOTSUP;
2539 }
2540
2541 memcpy(&msg.payload.session.u.asym.key, sess->key,
2542 sess->keylen);
2543 }
2544 } else {
2545 CryptoDevBackendSymSessionInfo *sess = &backend_info->u.sym_sess_info;
2546 size_t keylen;
2547
2548 memcpy(&msg.payload.session.u.sym.session_setup_data, sess,
2549 sizeof(CryptoDevBackendSymSessionInfo));
2550 if (sess->key_len) {
2551 keylen = sizeof(msg.payload.session.u.sym.key);
2552 if (sess->key_len > keylen) {
2553 error_report("Unsupported cipher key size");
2554 return -ENOTSUP;
2555 }
2556
2557 memcpy(&msg.payload.session.u.sym.key, sess->cipher_key,
2558 sess->key_len);
2559 }
2560
2561 if (sess->auth_key_len > 0) {
2562 keylen = sizeof(msg.payload.session.u.sym.auth_key);
2563 if (sess->auth_key_len > keylen) {
2564 error_report("Unsupported auth key size");
2565 return -ENOTSUP;
2566 }
2567
2568 memcpy(&msg.payload.session.u.sym.auth_key, sess->auth_key,
2569 sess->auth_key_len);
2570 }
2571 }
2572
2573 msg.payload.session.op_code = backend_info->op_code;
2574 msg.payload.session.session_id = backend_info->session_id;
2575 ret = vhost_user_write(dev, &msg, NULL, 0);
2576 if (ret < 0) {
2577 error_report("vhost_user_write() return %d, create session failed",
2578 ret);
2579 return ret;
2580 }
2581
2582 ret = vhost_user_read(dev, &msg);
2583 if (ret < 0) {
2584 error_report("vhost_user_read() return %d, create session failed",
2585 ret);
2586 return ret;
2587 }
2588
2589 if (msg.hdr.request != VHOST_USER_CREATE_CRYPTO_SESSION) {
2590 error_report("Received unexpected msg type. Expected %d received %d",
2591 VHOST_USER_CREATE_CRYPTO_SESSION, msg.hdr.request);
2592 return -EPROTO;
2593 }
2594
2595 if (msg.hdr.size != sizeof(msg.payload.session)) {
2596 error_report("Received bad msg size.");
2597 return -EPROTO;
2598 }
2599
2600 if (msg.payload.session.session_id < 0) {
2601 error_report("Bad session id: %" PRId64 "",
2602 msg.payload.session.session_id);
2603 return -EINVAL;
2604 }
2605 *session_id = msg.payload.session.session_id;
2606
2607 return 0;
2608 }
2609
2610 static int
vhost_user_crypto_close_session(struct vhost_dev * dev,uint64_t session_id)2611 vhost_user_crypto_close_session(struct vhost_dev *dev, uint64_t session_id)
2612 {
2613 int ret;
2614 bool crypto_session = virtio_has_feature(dev->protocol_features,
2615 VHOST_USER_PROTOCOL_F_CRYPTO_SESSION);
2616 VhostUserMsg msg = {
2617 .hdr.request = VHOST_USER_CLOSE_CRYPTO_SESSION,
2618 .hdr.flags = VHOST_USER_VERSION,
2619 .hdr.size = sizeof(msg.payload.u64),
2620 };
2621 msg.payload.u64 = session_id;
2622
2623 if (!crypto_session) {
2624 error_report("vhost-user trying to send unhandled ioctl");
2625 return -ENOTSUP;
2626 }
2627
2628 ret = vhost_user_write(dev, &msg, NULL, 0);
2629 if (ret < 0) {
2630 error_report("vhost_user_write() return %d, close session failed",
2631 ret);
2632 return ret;
2633 }
2634
2635 return 0;
2636 }
2637
vhost_user_no_private_memslots(struct vhost_dev * dev)2638 static bool vhost_user_no_private_memslots(struct vhost_dev *dev)
2639 {
2640 return true;
2641 }
2642
vhost_user_get_inflight_fd(struct vhost_dev * dev,uint16_t queue_size,struct vhost_inflight * inflight)2643 static int vhost_user_get_inflight_fd(struct vhost_dev *dev,
2644 uint16_t queue_size,
2645 struct vhost_inflight *inflight)
2646 {
2647 void *addr;
2648 int fd;
2649 int ret;
2650 struct vhost_user *u = dev->opaque;
2651 CharBackend *chr = u->user->chr;
2652 VhostUserMsg msg = {
2653 .hdr.request = VHOST_USER_GET_INFLIGHT_FD,
2654 .hdr.flags = VHOST_USER_VERSION,
2655 .payload.inflight.num_queues = dev->nvqs,
2656 .payload.inflight.queue_size = queue_size,
2657 .hdr.size = sizeof(msg.payload.inflight),
2658 };
2659
2660 if (!virtio_has_feature(dev->protocol_features,
2661 VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) {
2662 return 0;
2663 }
2664
2665 ret = vhost_user_write(dev, &msg, NULL, 0);
2666 if (ret < 0) {
2667 return ret;
2668 }
2669
2670 ret = vhost_user_read(dev, &msg);
2671 if (ret < 0) {
2672 return ret;
2673 }
2674
2675 if (msg.hdr.request != VHOST_USER_GET_INFLIGHT_FD) {
2676 error_report("Received unexpected msg type. "
2677 "Expected %d received %d",
2678 VHOST_USER_GET_INFLIGHT_FD, msg.hdr.request);
2679 return -EPROTO;
2680 }
2681
2682 if (msg.hdr.size != sizeof(msg.payload.inflight)) {
2683 error_report("Received bad msg size.");
2684 return -EPROTO;
2685 }
2686
2687 if (!msg.payload.inflight.mmap_size) {
2688 return 0;
2689 }
2690
2691 fd = qemu_chr_fe_get_msgfd(chr);
2692 if (fd < 0) {
2693 error_report("Failed to get mem fd");
2694 return -EIO;
2695 }
2696
2697 addr = mmap(0, msg.payload.inflight.mmap_size, PROT_READ | PROT_WRITE,
2698 MAP_SHARED, fd, msg.payload.inflight.mmap_offset);
2699
2700 if (addr == MAP_FAILED) {
2701 error_report("Failed to mmap mem fd");
2702 close(fd);
2703 return -EFAULT;
2704 }
2705
2706 inflight->addr = addr;
2707 inflight->fd = fd;
2708 inflight->size = msg.payload.inflight.mmap_size;
2709 inflight->offset = msg.payload.inflight.mmap_offset;
2710 inflight->queue_size = queue_size;
2711
2712 return 0;
2713 }
2714
vhost_user_set_inflight_fd(struct vhost_dev * dev,struct vhost_inflight * inflight)2715 static int vhost_user_set_inflight_fd(struct vhost_dev *dev,
2716 struct vhost_inflight *inflight)
2717 {
2718 VhostUserMsg msg = {
2719 .hdr.request = VHOST_USER_SET_INFLIGHT_FD,
2720 .hdr.flags = VHOST_USER_VERSION,
2721 .payload.inflight.mmap_size = inflight->size,
2722 .payload.inflight.mmap_offset = inflight->offset,
2723 .payload.inflight.num_queues = dev->nvqs,
2724 .payload.inflight.queue_size = inflight->queue_size,
2725 .hdr.size = sizeof(msg.payload.inflight),
2726 };
2727
2728 if (!virtio_has_feature(dev->protocol_features,
2729 VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD)) {
2730 return 0;
2731 }
2732
2733 return vhost_user_write(dev, &msg, &inflight->fd, 1);
2734 }
2735
vhost_user_state_destroy(gpointer data)2736 static void vhost_user_state_destroy(gpointer data)
2737 {
2738 VhostUserHostNotifier *n = (VhostUserHostNotifier *) data;
2739 if (n) {
2740 vhost_user_host_notifier_remove(n, NULL);
2741 object_unparent(OBJECT(&n->mr));
2742 /*
2743 * We can't free until vhost_user_host_notifier_remove has
2744 * done it's thing so schedule the free with RCU.
2745 */
2746 g_free_rcu(n, rcu);
2747 }
2748 }
2749
vhost_user_init(VhostUserState * user,CharBackend * chr,Error ** errp)2750 bool vhost_user_init(VhostUserState *user, CharBackend *chr, Error **errp)
2751 {
2752 if (user->chr) {
2753 error_setg(errp, "Cannot initialize vhost-user state");
2754 return false;
2755 }
2756 user->chr = chr;
2757 user->memory_slots = 0;
2758 user->notifiers = g_ptr_array_new_full(VIRTIO_QUEUE_MAX / 4,
2759 &vhost_user_state_destroy);
2760 return true;
2761 }
2762
vhost_user_cleanup(VhostUserState * user)2763 void vhost_user_cleanup(VhostUserState *user)
2764 {
2765 if (!user->chr) {
2766 return;
2767 }
2768 memory_region_transaction_begin();
2769 user->notifiers = (GPtrArray *) g_ptr_array_free(user->notifiers, true);
2770 memory_region_transaction_commit();
2771 user->chr = NULL;
2772 }
2773
2774
2775 typedef struct {
2776 vu_async_close_fn cb;
2777 DeviceState *dev;
2778 CharBackend *cd;
2779 struct vhost_dev *vhost;
2780 } VhostAsyncCallback;
2781
vhost_user_async_close_bh(void * opaque)2782 static void vhost_user_async_close_bh(void *opaque)
2783 {
2784 VhostAsyncCallback *data = opaque;
2785
2786 data->cb(data->dev);
2787
2788 g_free(data);
2789 }
2790
2791 /*
2792 * We only schedule the work if the machine is running. If suspended
2793 * we want to keep all the in-flight data as is for migration
2794 * purposes.
2795 */
vhost_user_async_close(DeviceState * d,CharBackend * chardev,struct vhost_dev * vhost,vu_async_close_fn cb)2796 void vhost_user_async_close(DeviceState *d,
2797 CharBackend *chardev, struct vhost_dev *vhost,
2798 vu_async_close_fn cb)
2799 {
2800 if (!runstate_check(RUN_STATE_SHUTDOWN)) {
2801 /*
2802 * A close event may happen during a read/write, but vhost
2803 * code assumes the vhost_dev remains setup, so delay the
2804 * stop & clear.
2805 */
2806 AioContext *ctx = qemu_get_current_aio_context();
2807 VhostAsyncCallback *data = g_new0(VhostAsyncCallback, 1);
2808
2809 /* Save data for the callback */
2810 data->cb = cb;
2811 data->dev = d;
2812 data->cd = chardev;
2813 data->vhost = vhost;
2814
2815 /* Disable any further notifications on the chardev */
2816 qemu_chr_fe_set_handlers(chardev,
2817 NULL, NULL, NULL, NULL, NULL, NULL,
2818 false);
2819
2820 aio_bh_schedule_oneshot(ctx, vhost_user_async_close_bh, data);
2821
2822 /*
2823 * Move vhost device to the stopped state. The vhost-user device
2824 * will be clean up and disconnected in BH. This can be useful in
2825 * the vhost migration code. If disconnect was caught there is an
2826 * option for the general vhost code to get the dev state without
2827 * knowing its type (in this case vhost-user).
2828 *
2829 * Note if the vhost device is fully cleared by the time we
2830 * execute the bottom half we won't continue with the cleanup.
2831 */
2832 vhost->started = false;
2833 }
2834 }
2835
vhost_user_dev_start(struct vhost_dev * dev,bool started)2836 static int vhost_user_dev_start(struct vhost_dev *dev, bool started)
2837 {
2838 if (!virtio_has_feature(dev->protocol_features,
2839 VHOST_USER_PROTOCOL_F_STATUS)) {
2840 return 0;
2841 }
2842
2843 /* Set device status only for last queue pair */
2844 if (dev->vq_index + dev->nvqs != dev->vq_index_end) {
2845 return 0;
2846 }
2847
2848 if (started) {
2849 return vhost_user_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE |
2850 VIRTIO_CONFIG_S_DRIVER |
2851 VIRTIO_CONFIG_S_DRIVER_OK);
2852 } else {
2853 return 0;
2854 }
2855 }
2856
vhost_user_reset_status(struct vhost_dev * dev)2857 static void vhost_user_reset_status(struct vhost_dev *dev)
2858 {
2859 /* Set device status only for last queue pair */
2860 if (dev->vq_index + dev->nvqs != dev->vq_index_end) {
2861 return;
2862 }
2863
2864 if (virtio_has_feature(dev->protocol_features,
2865 VHOST_USER_PROTOCOL_F_STATUS)) {
2866 vhost_user_set_status(dev, 0);
2867 }
2868 }
2869
vhost_user_supports_device_state(struct vhost_dev * dev)2870 static bool vhost_user_supports_device_state(struct vhost_dev *dev)
2871 {
2872 return virtio_has_feature(dev->protocol_features,
2873 VHOST_USER_PROTOCOL_F_DEVICE_STATE);
2874 }
2875
vhost_user_set_device_state_fd(struct vhost_dev * dev,VhostDeviceStateDirection direction,VhostDeviceStatePhase phase,int fd,int * reply_fd,Error ** errp)2876 static int vhost_user_set_device_state_fd(struct vhost_dev *dev,
2877 VhostDeviceStateDirection direction,
2878 VhostDeviceStatePhase phase,
2879 int fd,
2880 int *reply_fd,
2881 Error **errp)
2882 {
2883 int ret;
2884 struct vhost_user *vu = dev->opaque;
2885 VhostUserMsg msg = {
2886 .hdr = {
2887 .request = VHOST_USER_SET_DEVICE_STATE_FD,
2888 .flags = VHOST_USER_VERSION,
2889 .size = sizeof(msg.payload.transfer_state),
2890 },
2891 .payload.transfer_state = {
2892 .direction = direction,
2893 .phase = phase,
2894 },
2895 };
2896
2897 *reply_fd = -1;
2898
2899 if (!vhost_user_supports_device_state(dev)) {
2900 close(fd);
2901 error_setg(errp, "Back-end does not support migration state transfer");
2902 return -ENOTSUP;
2903 }
2904
2905 ret = vhost_user_write(dev, &msg, &fd, 1);
2906 close(fd);
2907 if (ret < 0) {
2908 error_setg_errno(errp, -ret,
2909 "Failed to send SET_DEVICE_STATE_FD message");
2910 return ret;
2911 }
2912
2913 ret = vhost_user_read(dev, &msg);
2914 if (ret < 0) {
2915 error_setg_errno(errp, -ret,
2916 "Failed to receive SET_DEVICE_STATE_FD reply");
2917 return ret;
2918 }
2919
2920 if (msg.hdr.request != VHOST_USER_SET_DEVICE_STATE_FD) {
2921 error_setg(errp,
2922 "Received unexpected message type, expected %d, received %d",
2923 VHOST_USER_SET_DEVICE_STATE_FD, msg.hdr.request);
2924 return -EPROTO;
2925 }
2926
2927 if (msg.hdr.size != sizeof(msg.payload.u64)) {
2928 error_setg(errp,
2929 "Received bad message size, expected %zu, received %" PRIu32,
2930 sizeof(msg.payload.u64), msg.hdr.size);
2931 return -EPROTO;
2932 }
2933
2934 if ((msg.payload.u64 & 0xff) != 0) {
2935 error_setg(errp, "Back-end did not accept migration state transfer");
2936 return -EIO;
2937 }
2938
2939 if (!(msg.payload.u64 & VHOST_USER_VRING_NOFD_MASK)) {
2940 *reply_fd = qemu_chr_fe_get_msgfd(vu->user->chr);
2941 if (*reply_fd < 0) {
2942 error_setg(errp,
2943 "Failed to get back-end-provided transfer pipe FD");
2944 *reply_fd = -1;
2945 return -EIO;
2946 }
2947 }
2948
2949 return 0;
2950 }
2951
vhost_user_check_device_state(struct vhost_dev * dev,Error ** errp)2952 static int vhost_user_check_device_state(struct vhost_dev *dev, Error **errp)
2953 {
2954 int ret;
2955 VhostUserMsg msg = {
2956 .hdr = {
2957 .request = VHOST_USER_CHECK_DEVICE_STATE,
2958 .flags = VHOST_USER_VERSION,
2959 .size = 0,
2960 },
2961 };
2962
2963 if (!vhost_user_supports_device_state(dev)) {
2964 error_setg(errp, "Back-end does not support migration state transfer");
2965 return -ENOTSUP;
2966 }
2967
2968 ret = vhost_user_write(dev, &msg, NULL, 0);
2969 if (ret < 0) {
2970 error_setg_errno(errp, -ret,
2971 "Failed to send CHECK_DEVICE_STATE message");
2972 return ret;
2973 }
2974
2975 ret = vhost_user_read(dev, &msg);
2976 if (ret < 0) {
2977 error_setg_errno(errp, -ret,
2978 "Failed to receive CHECK_DEVICE_STATE reply");
2979 return ret;
2980 }
2981
2982 if (msg.hdr.request != VHOST_USER_CHECK_DEVICE_STATE) {
2983 error_setg(errp,
2984 "Received unexpected message type, expected %d, received %d",
2985 VHOST_USER_CHECK_DEVICE_STATE, msg.hdr.request);
2986 return -EPROTO;
2987 }
2988
2989 if (msg.hdr.size != sizeof(msg.payload.u64)) {
2990 error_setg(errp,
2991 "Received bad message size, expected %zu, received %" PRIu32,
2992 sizeof(msg.payload.u64), msg.hdr.size);
2993 return -EPROTO;
2994 }
2995
2996 if (msg.payload.u64 != 0) {
2997 error_setg(errp, "Back-end failed to process its internal state");
2998 return -EIO;
2999 }
3000
3001 return 0;
3002 }
3003
3004 const VhostOps user_ops = {
3005 .backend_type = VHOST_BACKEND_TYPE_USER,
3006 .vhost_backend_init = vhost_user_backend_init,
3007 .vhost_backend_cleanup = vhost_user_backend_cleanup,
3008 .vhost_backend_memslots_limit = vhost_user_memslots_limit,
3009 .vhost_backend_no_private_memslots = vhost_user_no_private_memslots,
3010 .vhost_set_log_base = vhost_user_set_log_base,
3011 .vhost_set_mem_table = vhost_user_set_mem_table,
3012 .vhost_set_vring_addr = vhost_user_set_vring_addr,
3013 .vhost_set_vring_endian = vhost_user_set_vring_endian,
3014 .vhost_set_vring_num = vhost_user_set_vring_num,
3015 .vhost_set_vring_base = vhost_user_set_vring_base,
3016 .vhost_get_vring_base = vhost_user_get_vring_base,
3017 .vhost_set_vring_kick = vhost_user_set_vring_kick,
3018 .vhost_set_vring_call = vhost_user_set_vring_call,
3019 .vhost_set_vring_err = vhost_user_set_vring_err,
3020 .vhost_set_features = vhost_user_set_features,
3021 .vhost_get_features = vhost_user_get_features,
3022 .vhost_set_owner = vhost_user_set_owner,
3023 .vhost_reset_device = vhost_user_reset_device,
3024 .vhost_get_vq_index = vhost_user_get_vq_index,
3025 .vhost_set_vring_enable = vhost_user_set_vring_enable,
3026 .vhost_requires_shm_log = vhost_user_requires_shm_log,
3027 .vhost_migration_done = vhost_user_migration_done,
3028 .vhost_net_set_mtu = vhost_user_net_set_mtu,
3029 .vhost_set_iotlb_callback = vhost_user_set_iotlb_callback,
3030 .vhost_send_device_iotlb_msg = vhost_user_send_device_iotlb_msg,
3031 .vhost_get_config = vhost_user_get_config,
3032 .vhost_set_config = vhost_user_set_config,
3033 .vhost_crypto_create_session = vhost_user_crypto_create_session,
3034 .vhost_crypto_close_session = vhost_user_crypto_close_session,
3035 .vhost_get_inflight_fd = vhost_user_get_inflight_fd,
3036 .vhost_set_inflight_fd = vhost_user_set_inflight_fd,
3037 .vhost_dev_start = vhost_user_dev_start,
3038 .vhost_reset_status = vhost_user_reset_status,
3039 .vhost_supports_device_state = vhost_user_supports_device_state,
3040 .vhost_set_device_state_fd = vhost_user_set_device_state_fd,
3041 .vhost_check_device_state = vhost_user_check_device_state,
3042 };
3043