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1 /*
2 * Vhost User library
3 *
4 * Copyright (c) 2016 Red Hat, Inc.
5 *
6 * Authors:
7 * Victor Kaplansky <victork@redhat.com>
8 * Marc-André Lureau <mlureau@redhat.com>
9 *
10 * This work is licensed under the terms of the GNU GPL, version 2 or
11 * later. See the COPYING file in the top-level directory.
12 */
13
14 #ifndef LIBVHOST_USER_H
15 #define LIBVHOST_USER_H
16
17 #include <stdint.h>
18 #include <stdbool.h>
19 #include <stddef.h>
20 #include <poll.h>
21 #include <linux/vhost.h>
22 #include <pthread.h>
23 #include "standard-headers/linux/virtio_ring.h"
24
25 /* Based on qemu/hw/virtio/vhost-user.c */
26 #define VHOST_USER_F_PROTOCOL_FEATURES 30
27 #define VHOST_LOG_PAGE 4096
28
29 #define VIRTQUEUE_MAX_SIZE 1024
30
31 #define VHOST_MEMORY_BASELINE_NREGIONS 8
32
33 /*
34 * vhost in the kernel usually supports 509 mem slots. 509 used to be the
35 * KVM limit, it supported 512, but 3 were used for internal purposes. This
36 * limit is sufficient to support many DIMMs and virtio-mem in
37 * "dynamic-memslots" mode.
38 */
39 #define VHOST_USER_MAX_RAM_SLOTS 509
40
41 #define VHOST_USER_HDR_SIZE offsetof(VhostUserMsg, payload.u64)
42
43 typedef enum VhostSetConfigType {
44 VHOST_SET_CONFIG_TYPE_FRONTEND = 0,
45 VHOST_SET_CONFIG_TYPE_MIGRATION = 1,
46 } VhostSetConfigType;
47
48 /*
49 * Maximum size of virtio device config space
50 */
51 #define VHOST_USER_MAX_CONFIG_SIZE 256
52
53 enum VhostUserProtocolFeature {
54 VHOST_USER_PROTOCOL_F_MQ = 0,
55 VHOST_USER_PROTOCOL_F_LOG_SHMFD = 1,
56 VHOST_USER_PROTOCOL_F_RARP = 2,
57 VHOST_USER_PROTOCOL_F_REPLY_ACK = 3,
58 VHOST_USER_PROTOCOL_F_NET_MTU = 4,
59 VHOST_USER_PROTOCOL_F_BACKEND_REQ = 5,
60 VHOST_USER_PROTOCOL_F_CROSS_ENDIAN = 6,
61 VHOST_USER_PROTOCOL_F_CRYPTO_SESSION = 7,
62 VHOST_USER_PROTOCOL_F_PAGEFAULT = 8,
63 VHOST_USER_PROTOCOL_F_CONFIG = 9,
64 VHOST_USER_PROTOCOL_F_BACKEND_SEND_FD = 10,
65 VHOST_USER_PROTOCOL_F_HOST_NOTIFIER = 11,
66 VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD = 12,
67 VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS = 14,
68 VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS = 15,
69 /* Feature 16 is reserved for VHOST_USER_PROTOCOL_F_STATUS. */
70 /* Feature 17 reserved for VHOST_USER_PROTOCOL_F_XEN_MMAP. */
71 VHOST_USER_PROTOCOL_F_SHARED_OBJECT = 18,
72 /* Feature 19 is reserved for VHOST_USER_PROTOCOL_F_DEVICE_STATE */
73 /* Feature 20 is reserved for VHOST_USER_PROTOCOL_F_GET_VRING_BASE_INFLIGHT */
74 /* Feature 21 is reserved for VHOST_USER_PROTOCOL_F_GPA_ADDRESSES */
75 VHOST_USER_PROTOCOL_F_SHMEM = 22,
76 VHOST_USER_PROTOCOL_F_MAX
77 };
78
79 #define VHOST_USER_PROTOCOL_FEATURE_MASK ((1 << VHOST_USER_PROTOCOL_F_MAX) - 1)
80
81 typedef enum VhostUserRequest {
82 VHOST_USER_NONE = 0,
83 VHOST_USER_GET_FEATURES = 1,
84 VHOST_USER_SET_FEATURES = 2,
85 VHOST_USER_SET_OWNER = 3,
86 VHOST_USER_RESET_OWNER = 4,
87 VHOST_USER_SET_MEM_TABLE = 5,
88 VHOST_USER_SET_LOG_BASE = 6,
89 VHOST_USER_SET_LOG_FD = 7,
90 VHOST_USER_SET_VRING_NUM = 8,
91 VHOST_USER_SET_VRING_ADDR = 9,
92 VHOST_USER_SET_VRING_BASE = 10,
93 VHOST_USER_GET_VRING_BASE = 11,
94 VHOST_USER_SET_VRING_KICK = 12,
95 VHOST_USER_SET_VRING_CALL = 13,
96 VHOST_USER_SET_VRING_ERR = 14,
97 VHOST_USER_GET_PROTOCOL_FEATURES = 15,
98 VHOST_USER_SET_PROTOCOL_FEATURES = 16,
99 VHOST_USER_GET_QUEUE_NUM = 17,
100 VHOST_USER_SET_VRING_ENABLE = 18,
101 VHOST_USER_SEND_RARP = 19,
102 VHOST_USER_NET_SET_MTU = 20,
103 VHOST_USER_SET_BACKEND_REQ_FD = 21,
104 VHOST_USER_IOTLB_MSG = 22,
105 VHOST_USER_SET_VRING_ENDIAN = 23,
106 VHOST_USER_GET_CONFIG = 24,
107 VHOST_USER_SET_CONFIG = 25,
108 VHOST_USER_CREATE_CRYPTO_SESSION = 26,
109 VHOST_USER_CLOSE_CRYPTO_SESSION = 27,
110 VHOST_USER_POSTCOPY_ADVISE = 28,
111 VHOST_USER_POSTCOPY_LISTEN = 29,
112 VHOST_USER_POSTCOPY_END = 30,
113 VHOST_USER_GET_INFLIGHT_FD = 31,
114 VHOST_USER_SET_INFLIGHT_FD = 32,
115 VHOST_USER_GPU_SET_SOCKET = 33,
116 VHOST_USER_VRING_KICK = 35,
117 VHOST_USER_GET_MAX_MEM_SLOTS = 36,
118 VHOST_USER_ADD_MEM_REG = 37,
119 VHOST_USER_REM_MEM_REG = 38,
120 VHOST_USER_GET_SHARED_OBJECT = 41,
121 VHOST_USER_MAX
122 } VhostUserRequest;
123
124 typedef enum VhostUserBackendRequest {
125 VHOST_USER_BACKEND_NONE = 0,
126 VHOST_USER_BACKEND_IOTLB_MSG = 1,
127 VHOST_USER_BACKEND_CONFIG_CHANGE_MSG = 2,
128 VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG = 3,
129 VHOST_USER_BACKEND_VRING_CALL = 4,
130 VHOST_USER_BACKEND_VRING_ERR = 5,
131 VHOST_USER_BACKEND_SHARED_OBJECT_ADD = 6,
132 VHOST_USER_BACKEND_SHARED_OBJECT_REMOVE = 7,
133 VHOST_USER_BACKEND_SHARED_OBJECT_LOOKUP = 8,
134 VHOST_USER_BACKEND_SHMEM_MAP = 9,
135 VHOST_USER_BACKEND_SHMEM_UNMAP = 10,
136 VHOST_USER_BACKEND_MAX
137 } VhostUserBackendRequest;
138
139 typedef struct VhostUserMemoryRegion {
140 uint64_t guest_phys_addr;
141 uint64_t memory_size;
142 uint64_t userspace_addr;
143 uint64_t mmap_offset;
144 } VhostUserMemoryRegion;
145
146 #define VHOST_USER_MEM_REG_SIZE (sizeof(VhostUserMemoryRegion))
147
148 typedef struct VhostUserMemory {
149 uint32_t nregions;
150 uint32_t padding;
151 VhostUserMemoryRegion regions[VHOST_MEMORY_BASELINE_NREGIONS];
152 } VhostUserMemory;
153
154 typedef struct VhostUserMemRegMsg {
155 uint64_t padding;
156 VhostUserMemoryRegion region;
157 } VhostUserMemRegMsg;
158
159 typedef struct VhostUserLog {
160 uint64_t mmap_size;
161 uint64_t mmap_offset;
162 } VhostUserLog;
163
164 typedef struct VhostUserConfig {
165 uint32_t offset;
166 uint32_t size;
167 uint32_t flags;
168 uint8_t region[VHOST_USER_MAX_CONFIG_SIZE];
169 } VhostUserConfig;
170
171 static VhostUserConfig c __attribute__ ((unused));
172 #define VHOST_USER_CONFIG_HDR_SIZE (sizeof(c.offset) \
173 + sizeof(c.size) \
174 + sizeof(c.flags))
175
176 typedef struct VhostUserVringArea {
177 uint64_t u64;
178 uint64_t size;
179 uint64_t offset;
180 } VhostUserVringArea;
181
182 typedef struct VhostUserInflight {
183 uint64_t mmap_size;
184 uint64_t mmap_offset;
185 uint16_t num_queues;
186 uint16_t queue_size;
187 } VhostUserInflight;
188
189 #define UUID_LEN 16
190
191 typedef struct VhostUserShared {
192 unsigned char uuid[UUID_LEN];
193 } VhostUserShared;
194
195 /* For the flags field of VhostUserMMap */
196 #define VHOST_USER_FLAG_MAP_RW (1u << 0)
197
198 typedef struct {
199 /* VIRTIO Shared Memory Region ID */
200 uint8_t shmid;
201 uint8_t padding[7];
202 /* File offset */
203 uint64_t fd_offset;
204 /* Offset within the VIRTIO Shared Memory Region */
205 uint64_t shm_offset;
206 /* Size of the mapping */
207 uint64_t len;
208 /* Flags for the mmap operation, from VHOST_USER_FLAG_MAP_* */
209 uint64_t flags;
210 } VhostUserMMap;
211
212 #define VU_PACKED __attribute__((packed))
213
214 typedef struct VhostUserMsg {
215 int request;
216
217 #define VHOST_USER_VERSION_MASK (0x3)
218 #define VHOST_USER_REPLY_MASK (0x1 << 2)
219 #define VHOST_USER_NEED_REPLY_MASK (0x1 << 3)
220 uint32_t flags;
221 uint32_t size; /* the following payload size */
222
223 union {
224 #define VHOST_USER_VRING_IDX_MASK (0xff)
225 #define VHOST_USER_VRING_NOFD_MASK (0x1 << 8)
226 uint64_t u64;
227 struct vhost_vring_state state;
228 struct vhost_vring_addr addr;
229 VhostUserMemory memory;
230 VhostUserMemRegMsg memreg;
231 VhostUserLog log;
232 VhostUserConfig config;
233 VhostUserVringArea area;
234 VhostUserInflight inflight;
235 VhostUserShared object;
236 VhostUserMMap mmap;
237 } payload;
238
239 int fds[VHOST_MEMORY_BASELINE_NREGIONS];
240 int fd_num;
241 uint8_t *data;
242 } VU_PACKED VhostUserMsg;
243
244 typedef struct VuDevRegion {
245 /* Guest Physical address. */
246 uint64_t gpa;
247 /* Memory region size. */
248 uint64_t size;
249 /* QEMU virtual address (userspace). */
250 uint64_t qva;
251 /* Starting offset in our mmaped space. */
252 uint64_t mmap_offset;
253 /* Start address of mmaped space. */
254 uint64_t mmap_addr;
255 } VuDevRegion;
256
257 typedef struct VuDev VuDev;
258
259 typedef uint64_t (*vu_get_features_cb) (VuDev *dev);
260 typedef void (*vu_set_features_cb) (VuDev *dev, uint64_t features);
261 typedef int (*vu_process_msg_cb) (VuDev *dev, VhostUserMsg *vmsg,
262 int *do_reply);
263 typedef bool (*vu_read_msg_cb) (VuDev *dev, int sock, VhostUserMsg *vmsg);
264 typedef void (*vu_queue_set_started_cb) (VuDev *dev, int qidx, bool started);
265 typedef bool (*vu_queue_is_processed_in_order_cb) (VuDev *dev, int qidx);
266 typedef int (*vu_get_config_cb) (VuDev *dev, uint8_t *config, uint32_t len);
267 typedef int (*vu_set_config_cb) (VuDev *dev, const uint8_t *data,
268 uint32_t offset, uint32_t size,
269 uint32_t flags);
270 typedef int (*vu_get_shared_object_cb) (VuDev *dev, const unsigned char *uuid);
271
272 typedef struct VuDevIface {
273 /* called by VHOST_USER_GET_FEATURES to get the features bitmask */
274 vu_get_features_cb get_features;
275 /* enable vhost implementation features */
276 vu_set_features_cb set_features;
277 /* get the protocol feature bitmask from the underlying vhost
278 * implementation */
279 vu_get_features_cb get_protocol_features;
280 /* enable protocol features in the underlying vhost implementation. */
281 vu_set_features_cb set_protocol_features;
282 /* process_msg is called for each vhost-user message received */
283 /* skip libvhost-user processing if return value != 0 */
284 vu_process_msg_cb process_msg;
285 /* tells when queues can be processed */
286 vu_queue_set_started_cb queue_set_started;
287 /*
288 * If the queue is processed in order, in which case it will be
289 * resumed to vring.used->idx. This can help to support resuming
290 * on unmanaged exit/crash.
291 */
292 vu_queue_is_processed_in_order_cb queue_is_processed_in_order;
293 /* get the config space of the device */
294 vu_get_config_cb get_config;
295 /* set the config space of the device */
296 vu_set_config_cb set_config;
297 /* get virtio shared object from the underlying vhost implementation. */
298 vu_get_shared_object_cb get_shared_object;
299 } VuDevIface;
300
301 typedef void (*vu_queue_handler_cb) (VuDev *dev, int qidx);
302
303 typedef struct VuRing {
304 unsigned int num;
305 struct vring_desc *desc;
306 struct vring_avail *avail;
307 struct vring_used *used;
308 uint64_t log_guest_addr;
309 uint32_t flags;
310 } VuRing;
311
312 typedef struct VuDescStateSplit {
313 /* Indicate whether this descriptor is inflight or not.
314 * Only available for head-descriptor. */
315 uint8_t inflight;
316
317 /* Padding */
318 uint8_t padding[5];
319
320 /* Maintain a list for the last batch of used descriptors.
321 * Only available when batching is used for submitting */
322 uint16_t next;
323
324 /* Used to preserve the order of fetching available descriptors.
325 * Only available for head-descriptor. */
326 uint64_t counter;
327 } VuDescStateSplit;
328
329 typedef struct VuVirtqInflight {
330 /* The feature flags of this region. Now it's initialized to 0. */
331 uint64_t features;
332
333 /* The version of this region. It's 1 currently.
334 * Zero value indicates a vm reset happened. */
335 uint16_t version;
336
337 /*
338 * The size of VuDescStateSplit array. It's equal to the virtqueue size.
339 * Backend could get it from queue size field of VhostUserInflight.
340 */
341 uint16_t desc_num;
342
343 /* The head of list that track the last batch of used descriptors. */
344 uint16_t last_batch_head;
345
346 /* Storing the idx value of used ring */
347 uint16_t used_idx;
348
349 /* Used to track the state of each descriptor in descriptor table */
350 VuDescStateSplit desc[];
351 } VuVirtqInflight;
352
353 typedef struct VuVirtqInflightDesc {
354 uint16_t index;
355 uint64_t counter;
356 } VuVirtqInflightDesc;
357
358 typedef struct VuVirtq {
359 VuRing vring;
360
361 VuVirtqInflight *inflight;
362
363 VuVirtqInflightDesc *resubmit_list;
364
365 uint16_t resubmit_num;
366
367 uint64_t counter;
368
369 /* Next head to pop */
370 uint16_t last_avail_idx;
371
372 /* Last avail_idx read from VQ. */
373 uint16_t shadow_avail_idx;
374
375 uint16_t used_idx;
376
377 /* Last used index value we have signalled on */
378 uint16_t signalled_used;
379
380 /* Last used index value we have signalled on */
381 bool signalled_used_valid;
382
383 /* Notification enabled? */
384 bool notification;
385
386 unsigned int inuse;
387
388 vu_queue_handler_cb handler;
389
390 int call_fd;
391 int kick_fd;
392 int err_fd;
393 unsigned int enable;
394 bool started;
395
396 /* Guest addresses of our ring */
397 struct vhost_vring_addr vra;
398 } VuVirtq;
399
400 enum VuWatchCondtion {
401 VU_WATCH_IN = POLLIN,
402 VU_WATCH_OUT = POLLOUT,
403 VU_WATCH_PRI = POLLPRI,
404 VU_WATCH_ERR = POLLERR,
405 VU_WATCH_HUP = POLLHUP,
406 };
407
408 typedef void (*vu_panic_cb) (VuDev *dev, const char *err);
409 typedef void (*vu_watch_cb) (VuDev *dev, int condition, void *data);
410 typedef void (*vu_set_watch_cb) (VuDev *dev, int fd, int condition,
411 vu_watch_cb cb, void *data);
412 typedef void (*vu_remove_watch_cb) (VuDev *dev, int fd);
413
414 typedef struct VuDevInflightInfo {
415 int fd;
416 void *addr;
417 uint64_t size;
418 } VuDevInflightInfo;
419
420 struct VuDev {
421 int sock;
422 uint32_t nregions;
423 VuDevRegion *regions;
424 VuVirtq *vq;
425 VuDevInflightInfo inflight_info;
426 int log_call_fd;
427 /* Must be held while using backend_fd */
428 pthread_mutex_t backend_mutex;
429 int backend_fd;
430 uint64_t log_size;
431 uint8_t *log_table;
432 uint64_t features;
433 uint64_t protocol_features;
434 bool broken;
435 uint16_t max_queues;
436
437 /*
438 * @read_msg: custom method to read vhost-user message
439 *
440 * Read data from vhost_user socket fd and fill up
441 * the passed VhostUserMsg *vmsg struct.
442 *
443 * If reading fails, it should close the received set of file
444 * descriptors as socket message's auxiliary data.
445 *
446 * For the details, please refer to vu_message_read in libvhost-user.c
447 * which will be used by default if not custom method is provided when
448 * calling vu_init
449 *
450 * Returns: true if vhost-user message successfully received,
451 * otherwise return false.
452 *
453 */
454 vu_read_msg_cb read_msg;
455
456 /*
457 * @set_watch: add or update the given fd to the watch set,
458 * call cb when condition is met.
459 */
460 vu_set_watch_cb set_watch;
461
462 /* @remove_watch: remove the given fd from the watch set */
463 vu_remove_watch_cb remove_watch;
464
465 /*
466 * @panic: encountered an unrecoverable error, you may try to re-initialize
467 */
468 vu_panic_cb panic;
469 const VuDevIface *iface;
470
471 /* Postcopy data */
472 int postcopy_ufd;
473 bool postcopy_listening;
474 };
475
476 typedef struct VuVirtqElement {
477 unsigned int index;
478 unsigned int out_num;
479 unsigned int in_num;
480 struct iovec *in_sg;
481 struct iovec *out_sg;
482 } VuVirtqElement;
483
484 /**
485 * vu_init:
486 * @dev: a VuDev context
487 * @max_queues: maximum number of virtqueues
488 * @socket: the socket connected to vhost-user frontend
489 * @panic: a panic callback
490 * @set_watch: a set_watch callback
491 * @remove_watch: a remove_watch callback
492 * @iface: a VuDevIface structure with vhost-user device callbacks
493 *
494 * Initializes a VuDev vhost-user context.
495 *
496 * Returns: true on success, false on failure.
497 **/
498 bool vu_init(VuDev *dev,
499 uint16_t max_queues,
500 int socket,
501 vu_panic_cb panic,
502 vu_read_msg_cb read_msg,
503 vu_set_watch_cb set_watch,
504 vu_remove_watch_cb remove_watch,
505 const VuDevIface *iface);
506
507
508 /**
509 * vu_deinit:
510 * @dev: a VuDev context
511 *
512 * Cleans up the VuDev context
513 */
514 void vu_deinit(VuDev *dev);
515
516
517 /**
518 * vu_request_to_string: return string for vhost message request
519 * @req: VhostUserMsg request
520 *
521 * Returns a const string, do not free.
522 */
523 const char *vu_request_to_string(unsigned int req);
524
525 /**
526 * vu_dispatch:
527 * @dev: a VuDev context
528 *
529 * Process one vhost-user message.
530 *
531 * Returns: TRUE on success, FALSE on failure.
532 */
533 bool vu_dispatch(VuDev *dev);
534
535 /**
536 * vu_gpa_to_va:
537 * @dev: a VuDev context
538 * @plen: guest memory size
539 * @guest_addr: guest address
540 *
541 * Translate a guest address to a pointer. Returns NULL on failure.
542 */
543 void *vu_gpa_to_va(VuDev *dev, uint64_t *plen, uint64_t guest_addr);
544
545 /**
546 * vu_get_queue:
547 * @dev: a VuDev context
548 * @qidx: queue index
549 *
550 * Returns the queue number @qidx.
551 */
552 VuVirtq *vu_get_queue(VuDev *dev, int qidx);
553
554 /**
555 * vu_set_queue_handler:
556 * @dev: a VuDev context
557 * @vq: a VuVirtq queue
558 * @handler: the queue handler callback
559 *
560 * Set the queue handler. This function may be called several times
561 * for the same queue. If called with NULL @handler, the handler is
562 * removed.
563 */
564 void vu_set_queue_handler(VuDev *dev, VuVirtq *vq,
565 vu_queue_handler_cb handler);
566
567 /**
568 * vu_set_queue_host_notifier:
569 * @dev: a VuDev context
570 * @vq: a VuVirtq queue
571 * @fd: a file descriptor
572 * @size: host page size
573 * @offset: notifier offset in @fd file
574 *
575 * Set queue's host notifier. This function may be called several
576 * times for the same queue. If called with -1 @fd, the notifier
577 * is removed.
578 */
579 bool vu_set_queue_host_notifier(VuDev *dev, VuVirtq *vq, int fd,
580 int size, int offset);
581
582 /**
583 * vu_lookup_shared_object:
584 * @dev: a VuDev context
585 * @uuid: UUID of the shared object
586 * @dmabuf_fd: output dma-buf file descriptor
587 *
588 * Lookup for a virtio shared object (i.e., dma-buf fd) associated with the
589 * received UUID. Result, if found, is stored in the dmabuf_fd argument.
590 *
591 * Returns: whether the virtio object was found.
592 */
593 bool vu_lookup_shared_object(VuDev *dev, unsigned char uuid[UUID_LEN],
594 int *dmabuf_fd);
595
596 /**
597 * vu_add_shared_object:
598 * @dev: a VuDev context
599 * @uuid: UUID of the shared object
600 *
601 * Registers this back-end as the exporter for the object associated with
602 * the received UUID.
603 *
604 * Returns: TRUE on success, FALSE on failure.
605 */
606 bool vu_add_shared_object(VuDev *dev, unsigned char uuid[UUID_LEN]);
607
608 /**
609 * vu_rm_shared_object:
610 * @dev: a VuDev context
611 * @uuid: UUID of the shared object
612 *
613 * Removes a shared object entry (i.e., back-end entry) associated with the
614 * received UUID key from the hash table.
615 *
616 * Returns: TRUE on success, FALSE on failure.
617 */
618 bool vu_rm_shared_object(VuDev *dev, unsigned char uuid[UUID_LEN]);
619
620 /**
621 * vu_shmem_map:
622 * @dev: a VuDev context
623 * @shmid: VIRTIO Shared Memory Region ID
624 * @fd_offset: File offset
625 * @shm_offset: Offset within the VIRTIO Shared Memory Region
626 * @len: Size of the mapping
627 * @flags: Flags for the mmap operation
628 * @fd: A file descriptor
629 *
630 * Advertises a new mapping to be made in a given VIRTIO Shared Memory Region.
631 *
632 * Returns: TRUE on success, FALSE on failure.
633 */
634 bool vu_shmem_map(VuDev *dev, uint8_t shmid, uint64_t fd_offset,
635 uint64_t shm_offset, uint64_t len, uint64_t flags, int fd);
636
637 /**
638 * vu_shmem_unmap:
639 * @dev: a VuDev context
640 * @shmid: VIRTIO Shared Memory Region ID
641 * @fd_offset: File offset
642 * @len: Size of the mapping
643 *
644 * The front-end un-mmaps a given range in the VIRTIO Shared Memory Region
645 * with the requested `shmid`.
646 *
647 * Returns: TRUE on success, FALSE on failure.
648 */
649 bool vu_shmem_unmap(VuDev *dev, uint8_t shmid, uint64_t shm_offset,
650 uint64_t len);
651
652 /**
653 * vu_queue_set_notification:
654 * @dev: a VuDev context
655 * @vq: a VuVirtq queue
656 * @enable: state
657 *
658 * Set whether the queue notifies (via event index or interrupt)
659 */
660 void vu_queue_set_notification(VuDev *dev, VuVirtq *vq, int enable);
661
662 /**
663 * vu_queue_enabled:
664 * @dev: a VuDev context
665 * @vq: a VuVirtq queue
666 *
667 * Returns: whether the queue is enabled.
668 */
669 bool vu_queue_enabled(VuDev *dev, VuVirtq *vq);
670
671 /**
672 * vu_queue_started:
673 * @dev: a VuDev context
674 * @vq: a VuVirtq queue
675 *
676 * Returns: whether the queue is started.
677 */
678 bool vu_queue_started(const VuDev *dev, const VuVirtq *vq);
679
680 /**
681 * vu_queue_empty:
682 * @dev: a VuDev context
683 * @vq: a VuVirtq queue
684 *
685 * Returns: true if the queue is empty or not ready.
686 */
687 bool vu_queue_empty(VuDev *dev, VuVirtq *vq);
688
689 /**
690 * vu_queue_notify:
691 * @dev: a VuDev context
692 * @vq: a VuVirtq queue
693 *
694 * Request to notify the queue via callfd (skipped if unnecessary)
695 */
696 void vu_queue_notify(VuDev *dev, VuVirtq *vq);
697
698 void vu_config_change_msg(VuDev *dev);
699
700 /**
701 * vu_queue_notify_sync:
702 * @dev: a VuDev context
703 * @vq: a VuVirtq queue
704 *
705 * Request to notify the queue via callfd (skipped if unnecessary)
706 * or sync message if possible.
707 */
708 void vu_queue_notify_sync(VuDev *dev, VuVirtq *vq);
709
710 /**
711 * vu_queue_pop:
712 * @dev: a VuDev context
713 * @vq: a VuVirtq queue
714 * @sz: the size of struct to return (must be >= VuVirtqElement)
715 *
716 * Returns: a VuVirtqElement filled from the queue or NULL. The
717 * returned element must be free()-d by the caller.
718 */
719 void *vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz);
720
721
722 /**
723 * vu_queue_unpop:
724 * @dev: a VuDev context
725 * @vq: a VuVirtq queue
726 * @elem: The #VuVirtqElement
727 * @len: number of bytes written
728 *
729 * Pretend the most recent element wasn't popped from the virtqueue. The next
730 * call to vu_queue_pop() will refetch the element.
731 */
732 void vu_queue_unpop(VuDev *dev, VuVirtq *vq, VuVirtqElement *elem,
733 size_t len);
734
735 /**
736 * vu_queue_rewind:
737 * @dev: a VuDev context
738 * @vq: a VuVirtq queue
739 * @num: number of elements to push back
740 *
741 * Pretend that elements weren't popped from the virtqueue. The next
742 * virtqueue_pop() will refetch the oldest element.
743 *
744 * Returns: true on success, false if @num is greater than the number of in use
745 * elements.
746 */
747 bool vu_queue_rewind(VuDev *dev, VuVirtq *vq, unsigned int num);
748
749 /**
750 * vu_queue_fill:
751 * @dev: a VuDev context
752 * @vq: a VuVirtq queue
753 * @elem: a VuVirtqElement
754 * @len: length in bytes to write
755 * @idx: optional offset for the used ring index (0 in general)
756 *
757 * Fill the used ring with @elem element.
758 */
759 void vu_queue_fill(VuDev *dev, VuVirtq *vq,
760 const VuVirtqElement *elem,
761 unsigned int len, unsigned int idx);
762
763 /**
764 * vu_queue_push:
765 * @dev: a VuDev context
766 * @vq: a VuVirtq queue
767 * @elem: a VuVirtqElement
768 * @len: length in bytes to write
769 *
770 * Helper that combines vu_queue_fill() with a vu_queue_flush().
771 */
772 void vu_queue_push(VuDev *dev, VuVirtq *vq,
773 const VuVirtqElement *elem, unsigned int len);
774
775 /**
776 * vu_queue_flush:
777 * @dev: a VuDev context
778 * @vq: a VuVirtq queue
779 * @num: number of elements to flush
780 *
781 * Mark the last number of elements as done (used.idx is updated by
782 * num elements).
783 */
784 void vu_queue_flush(VuDev *dev, VuVirtq *vq, unsigned int num);
785
786 /**
787 * vu_queue_get_avail_bytes:
788 * @dev: a VuDev context
789 * @vq: a VuVirtq queue
790 * @in_bytes: in bytes
791 * @out_bytes: out bytes
792 * @max_in_bytes: stop counting after max_in_bytes
793 * @max_out_bytes: stop counting after max_out_bytes
794 *
795 * Count the number of available bytes, up to max_in_bytes/max_out_bytes.
796 */
797 void vu_queue_get_avail_bytes(VuDev *vdev, VuVirtq *vq, unsigned int *in_bytes,
798 unsigned int *out_bytes,
799 unsigned max_in_bytes, unsigned max_out_bytes);
800
801 /**
802 * vu_queue_avail_bytes:
803 * @dev: a VuDev context
804 * @vq: a VuVirtq queue
805 * @in_bytes: expected in bytes
806 * @out_bytes: expected out bytes
807 *
808 * Returns: true if in_bytes <= in_total && out_bytes <= out_total
809 */
810 bool vu_queue_avail_bytes(VuDev *dev, VuVirtq *vq, unsigned int in_bytes,
811 unsigned int out_bytes);
812
813 #endif /* LIBVHOST_USER_H */