xref: /freebsd/sys/dev/vmware/vmci/vmci_kernel_if.c (revision d4eeb02986980bf33dd56c41ceb9fc5f180c0d47)
1 /*-
2  * Copyright (c) 2018 VMware, Inc.
3  *
4  * SPDX-License-Identifier: (BSD-2-Clause OR GPL-2.0)
5  */
6 
7 /* This file implements defines and helper functions. */
8 
9 #include <sys/cdefs.h>
10 __FBSDID("$FreeBSD$");
11 
12 #include <sys/malloc.h>
13 #include <sys/proc.h>
14 #include <sys/uio.h>
15 
16 #include <machine/bus.h>
17 
18 #include "vmci.h"
19 #include "vmci_defs.h"
20 #include "vmci_kernel_defs.h"
21 #include "vmci_kernel_if.h"
22 #include "vmci_queue.h"
23 
24 struct vmci_queue_kernel_if {
25 	size_t			num_pages;	/* Num pages incl. header. */
26 	struct vmci_dma_alloc	*dmas;		/* For dma alloc. */
27 };
28 
29 /*
30  *------------------------------------------------------------------------------
31  *
32  * vmci_init_lock
33  *
34  *     Initializes the lock. Must be called before use.
35  *
36  * Results:
37  *     Always VMCI_SUCCESS.
38  *
39  * Side effects:
40  *     Thread can block.
41  *
42  *------------------------------------------------------------------------------
43  */
44 
45 int
46 vmci_init_lock(vmci_lock *lock, char *name)
47 {
48 
49 	mtx_init(lock, name, NULL, MTX_DEF | MTX_NOWITNESS);
50 	return (VMCI_SUCCESS);
51 }
52 
53 /*
54  *------------------------------------------------------------------------------
55  *
56  * vmci_cleanup_lock
57  *
58  *     Cleanup the lock. Must be called before deallocating lock.
59  *
60  * Results:
61  *     None
62  *
63  * Side effects:
64  *     Deletes kernel lock state
65  *
66  *------------------------------------------------------------------------------
67  */
68 
69 void
70 vmci_cleanup_lock(vmci_lock *lock)
71 {
72 
73 	if (mtx_initialized(lock))
74 		mtx_destroy(lock);
75 }
76 
77 /*
78  *------------------------------------------------------------------------------
79  *
80  * vmci_grab_lock
81  *
82  *     Grabs the given lock.
83  *
84  * Results:
85  *      None
86  *
87  * Side effects:
88  *      Thread can block.
89  *
90  *------------------------------------------------------------------------------
91  */
92 
93 void
94 vmci_grab_lock(vmci_lock *lock)
95 {
96 
97 	mtx_lock(lock);
98 }
99 
100 /*
101  *------------------------------------------------------------------------------
102  *
103  * vmci_release_lock
104  *
105  *     Releases the given lock.
106  *
107  * Results:
108  *     None
109  *
110  * Side effects:
111  *     A thread blocked on this lock may wake up.
112  *
113  *------------------------------------------------------------------------------
114  */
115 
116 void
117 vmci_release_lock(vmci_lock *lock)
118 {
119 
120 	mtx_unlock(lock);
121 }
122 
123 /*
124  *------------------------------------------------------------------------------
125  *
126  * vmci_grab_lock_bh
127  *
128  *     Grabs the given lock.
129  *
130  * Results:
131  *     None
132  *
133  * Side effects:
134  *     None.
135  *
136  *------------------------------------------------------------------------------
137  */
138 
139 void
140 vmci_grab_lock_bh(vmci_lock *lock)
141 {
142 
143 	mtx_lock(lock);
144 }
145 
146 /*
147  *------------------------------------------------------------------------------
148  *
149  * vmci_release_lock_bh
150  *
151  *     Releases the given lock.
152  *
153  * Results:
154  *     None
155  *
156  * Side effects:
157  *     None.
158  *
159  *------------------------------------------------------------------------------
160  */
161 
162 void
163 vmci_release_lock_bh(vmci_lock *lock)
164 {
165 
166 	mtx_unlock(lock);
167 }
168 
169 /*
170  *------------------------------------------------------------------------------
171  *
172  * vmci_initialized_lock
173  *
174  *     Returns whether a lock has been initialized.
175  *
176  * Results:
177  *     Return 1 if initialized or 0 if unininitialized.
178  *
179  * Side effects:
180  *     None
181  *
182  *------------------------------------------------------------------------------
183  */
184 
185 int
186 vmci_initialized_lock(vmci_lock *lock)
187 {
188 
189 	return mtx_initialized(lock);
190 }
191 
192 /*
193  *------------------------------------------------------------------------------
194  *
195  * vmci_alloc_kernel_mem
196  *
197  *     Allocate physically contiguous memory for the VMCI driver.
198  *
199  * Results:
200  *     The address allocated or NULL on error.
201  *
202  *
203  * Side effects:
204  *     Memory may be allocated.
205  *
206  *------------------------------------------------------------------------------
207  */
208 
209 void *
210 vmci_alloc_kernel_mem(size_t size, int flags)
211 {
212 	void *ptr;
213 
214 	if ((flags & VMCI_MEMORY_ATOMIC) != 0)
215 		ptr = contigmalloc(size, M_DEVBUF, M_NOWAIT, 0, 0xFFFFFFFF,
216 		    8, 1024 * 1024);
217 	else
218 		ptr = contigmalloc(size, M_DEVBUF, M_WAITOK, 0, 0xFFFFFFFF,
219 		    8, 1024 * 1024);
220 
221 	return (ptr);
222 }
223 
224 /*
225  *------------------------------------------------------------------------------
226  *
227  * vmci_free_kernel_mem
228  *
229  *     Free kernel memory allocated for the VMCI driver.
230  *
231  * Results:
232  *     None.
233  *
234  * Side effects:
235  *     Memory is freed.
236  *
237  *------------------------------------------------------------------------------
238  */
239 
240 void
241 vmci_free_kernel_mem(void *ptr, size_t size)
242 {
243 
244 	contigfree(ptr, size, M_DEVBUF);
245 }
246 
247 /*
248  *------------------------------------------------------------------------------
249  *
250  * vmci_can_schedule_delayed_work --
251  *
252  *     Checks to see if the given platform supports delayed work callbacks.
253  *
254  * Results:
255  *     true if it does. false otherwise.
256  *
257  * Side effects:
258  *     None.
259  *
260  *------------------------------------------------------------------------------
261  */
262 
263 bool
264 vmci_can_schedule_delayed_work(void)
265 {
266 
267 	return (true);
268 }
269 
270 /*
271  *------------------------------------------------------------------------------
272  *
273  * vmci_schedule_delayed_work --
274  *
275  *     Schedule the specified callback.
276  *
277  * Results:
278  *     Zero on success, error code otherwise.
279  *
280  * Side effects:
281  *     None.
282  *
283  *------------------------------------------------------------------------------
284  */
285 
286 int
287 vmci_schedule_delayed_work(vmci_work_fn *work_fn, void *data)
288 {
289 
290 	return (vmci_schedule_delayed_work_fn(work_fn, data));
291 }
292 
293 /*
294  *------------------------------------------------------------------------------
295  *
296  * vmci_create_event --
297  *
298  * Results:
299  *     None.
300  *
301  * Side effects:
302  *     None.
303  *
304  *------------------------------------------------------------------------------
305  */
306 
307 void
308 vmci_create_event(vmci_event *event)
309 {
310 
311 	sema_init(event, 0, "vmci_event");
312 }
313 
314 /*
315  *------------------------------------------------------------------------------
316  *
317  * vmci_destroy_event --
318  *
319  * Results:
320  *     None.
321  *
322  * Side effects:
323  *     None.
324  *
325  *------------------------------------------------------------------------------
326  */
327 
328 void
329 vmci_destroy_event(vmci_event *event)
330 {
331 
332 	if (mtx_owned(&event->sema_mtx))
333 		sema_destroy(event);
334 }
335 
336 /*
337  *------------------------------------------------------------------------------
338  *
339  * vmci_signal_event --
340  *
341  * Results:
342  *     None.
343  *
344  * Side effects:
345  *     None.
346  *
347  *------------------------------------------------------------------------------
348  */
349 
350 void
351 vmci_signal_event(vmci_event *event)
352 {
353 
354 	sema_post(event);
355 }
356 
357 /*
358  *------------------------------------------------------------------------------
359  *
360  * vmci_wait_on_event --
361  *
362  * Results:
363  *     None.
364  *
365  * Side effects:
366  *     None.
367  *
368  *------------------------------------------------------------------------------
369  */
370 
371 void
372 vmci_wait_on_event(vmci_event *event, vmci_event_release_cb release_cb,
373     void *client_data)
374 {
375 
376 	release_cb(client_data);
377 	sema_wait(event);
378 }
379 
380 /*
381  *------------------------------------------------------------------------------
382  *
383  * vmci_mutex_init --
384  *
385  *     Initializes the mutex. Must be called before use.
386  *
387  * Results:
388  *     Success.
389  *
390  * Side effects:
391  *     None.
392  *
393  *------------------------------------------------------------------------------
394  */
395 
396 int
397 vmci_mutex_init(vmci_mutex *mutex, char *name)
398 {
399 
400 	mtx_init(mutex, name, NULL, MTX_DEF | MTX_NOWITNESS);
401 	return (VMCI_SUCCESS);
402 }
403 
404 /*
405  *------------------------------------------------------------------------------
406  *
407  * vmci_mutex_destroy --
408  *
409  *     Destroys the mutex.
410  *
411  * Results:
412  *     None.
413  *
414  * Side effects:
415  *     None.
416  *
417  *------------------------------------------------------------------------------
418  */
419 
420 void
421 vmci_mutex_destroy(vmci_mutex *mutex)
422 {
423 
424 	mtx_destroy(mutex);
425 }
426 
427 /*
428  *------------------------------------------------------------------------------
429  *
430  * vmci_mutex_acquire --
431  *
432  *     Acquires the mutex.
433  *
434  * Results:
435  *     None.
436  *
437  * Side effects:
438  *     Thread may block.
439  *
440  *------------------------------------------------------------------------------
441  */
442 
443 void
444 vmci_mutex_acquire(vmci_mutex *mutex)
445 {
446 
447 	mtx_lock(mutex);
448 }
449 
450 /*
451  *------------------------------------------------------------------------------
452  *
453  * vmci_mutex_release --
454  *
455  *     Releases the mutex.
456  *
457  * Results:
458  *     None.
459  *
460  * Side effects:
461  *     May wake up the thread blocking on this mutex.
462  *
463  *------------------------------------------------------------------------------
464  */
465 
466 void
467 vmci_mutex_release(vmci_mutex *mutex)
468 {
469 
470 	mtx_unlock(mutex);
471 }
472 
473 /*
474  *------------------------------------------------------------------------------
475  *
476  * vmci_mutex_initialized
477  *
478  *     Returns whether a mutex has been initialized.
479  *
480  * Results:
481  *     Return 1 if initialized or 0 if unininitialized.
482  *
483  * Side effects:
484  *     None
485  *
486  *------------------------------------------------------------------------------
487  */
488 
489 int
490 vmci_mutex_initialized(vmci_mutex *mutex)
491 {
492 
493 	return mtx_initialized(mutex);
494 }
495 /*
496  *------------------------------------------------------------------------------
497  *
498  * vmci_alloc_queue --
499  *
500  *     Allocates kernel queue pages of specified size with IOMMU mappings, plus
501  *     space for the queue structure/kernel interface and the queue header.
502  *
503  * Results:
504  *     Pointer to the queue on success, NULL otherwise.
505  *
506  * Side effects:
507  *     Memory is allocated.
508  *
509  *------------------------------------------------------------------------------
510  */
511 
512 void *
513 vmci_alloc_queue(uint64_t size, uint32_t flags)
514 {
515 	struct vmci_queue *queue;
516 	size_t i;
517 	const size_t num_pages = CEILING(size, PAGE_SIZE) + 1;
518 	const size_t dmas_size = num_pages * sizeof(struct vmci_dma_alloc);
519 	const size_t queue_size =
520 	    sizeof(*queue) + sizeof(*(queue->kernel_if)) + dmas_size;
521 
522 	/* Size should be enforced by vmci_qpair_alloc(), double-check here. */
523 	if (size > VMCI_MAX_GUEST_QP_MEMORY) {
524 		ASSERT(false);
525 		return (NULL);
526 	}
527 
528 	queue = malloc(queue_size, M_DEVBUF, M_NOWAIT);
529 	if (!queue)
530 		return (NULL);
531 
532 	queue->q_header = NULL;
533 	queue->saved_header = NULL;
534 	queue->kernel_if = (struct vmci_queue_kernel_if *)(queue + 1);
535 	queue->kernel_if->num_pages = num_pages;
536 	queue->kernel_if->dmas = (struct vmci_dma_alloc *)(queue->kernel_if +
537 	    1);
538 	for (i = 0; i < num_pages; i++) {
539 		vmci_dma_malloc(PAGE_SIZE, 1, &queue->kernel_if->dmas[i]);
540 		if (!queue->kernel_if->dmas[i].dma_vaddr) {
541 			/* Size excl. the header. */
542 			vmci_free_queue(queue, i * PAGE_SIZE);
543 			return (NULL);
544 		}
545 	}
546 
547 	/* Queue header is the first page. */
548 	queue->q_header = (void *)queue->kernel_if->dmas[0].dma_vaddr;
549 
550 	return ((void *)queue);
551 }
552 
553 /*
554  *------------------------------------------------------------------------------
555  *
556  * vmci_free_queue --
557  *
558  *     Frees kernel VA space for a given queue and its queue header, and frees
559  *     physical data pages.
560  *
561  * Results:
562  *     None.
563  *
564  * Side effects:
565  *     Memory is freed.
566  *
567  *------------------------------------------------------------------------------
568  */
569 
570 void
571 vmci_free_queue(void *q, uint64_t size)
572 {
573 	struct vmci_queue *queue = q;
574 
575 	if (queue) {
576 		const size_t num_pages = CEILING(size, PAGE_SIZE) + 1;
577 		uint64_t i;
578 
579 		/* Given size doesn't include header, so add in a page here. */
580 		for (i = 0; i < num_pages; i++)
581 			vmci_dma_free(&queue->kernel_if->dmas[i]);
582 		free(queue, M_DEVBUF);
583 	}
584 }
585 
586 /*
587  *------------------------------------------------------------------------------
588  *
589  * vmci_alloc_ppn_set --
590  *
591  *     Allocates two list of PPNs --- one for the pages in the produce queue,
592  *     and the other for the pages in the consume queue. Intializes the list of
593  *     PPNs with the page frame numbers of the KVA for the two queues (and the
594  *     queue headers).
595  *
596  * Results:
597  *     Success or failure.
598  *
599  * Side effects:
600  *     Memory may be allocated.
601  *
602  *-----------------------------------------------------------------------------
603  */
604 
605 int
606 vmci_alloc_ppn_set(void *prod_q, uint64_t num_produce_pages, void *cons_q,
607     uint64_t num_consume_pages, struct ppn_set *ppn_set)
608 {
609 	struct vmci_queue *consume_q = cons_q;
610 	struct vmci_queue *produce_q = prod_q;
611 	vmci_ppn_list consume_ppns;
612 	vmci_ppn_list produce_ppns;
613 	uint64_t i;
614 
615 	if (!produce_q || !num_produce_pages || !consume_q ||
616 	    !num_consume_pages || !ppn_set)
617 		return (VMCI_ERROR_INVALID_ARGS);
618 
619 	if (ppn_set->initialized)
620 		return (VMCI_ERROR_ALREADY_EXISTS);
621 
622 	produce_ppns =
623 	    vmci_alloc_kernel_mem(num_produce_pages * sizeof(*produce_ppns),
624 	    VMCI_MEMORY_NORMAL);
625 	if (!produce_ppns)
626 		return (VMCI_ERROR_NO_MEM);
627 
628 	consume_ppns =
629 	    vmci_alloc_kernel_mem(num_consume_pages * sizeof(*consume_ppns),
630 	    VMCI_MEMORY_NORMAL);
631 	if (!consume_ppns) {
632 		vmci_free_kernel_mem(produce_ppns,
633 		    num_produce_pages * sizeof(*produce_ppns));
634 		return (VMCI_ERROR_NO_MEM);
635 	}
636 
637 	for (i = 0; i < num_produce_pages; i++) {
638 		unsigned long pfn;
639 
640 		produce_ppns[i] =
641 		    pfn = produce_q->kernel_if->dmas[i].dma_paddr >> PAGE_SHIFT;
642 
643 		/*
644 		 * Fail allocation if PFN isn't supported by hypervisor.
645 		 */
646 
647 		if (sizeof(pfn) >
648 		    sizeof(*produce_ppns) && pfn != produce_ppns[i])
649 			goto ppn_error;
650 	}
651 	for (i = 0; i < num_consume_pages; i++) {
652 		unsigned long pfn;
653 
654 		consume_ppns[i] =
655 		    pfn = consume_q->kernel_if->dmas[i].dma_paddr >> PAGE_SHIFT;
656 
657 		/*
658 		 * Fail allocation if PFN isn't supported by hypervisor.
659 		 */
660 
661 		if (sizeof(pfn) >
662 		    sizeof(*consume_ppns) && pfn != consume_ppns[i])
663 			goto ppn_error;
664 	}
665 
666 	ppn_set->num_produce_pages = num_produce_pages;
667 	ppn_set->num_consume_pages = num_consume_pages;
668 	ppn_set->produce_ppns = produce_ppns;
669 	ppn_set->consume_ppns = consume_ppns;
670 	ppn_set->initialized = true;
671 	return (VMCI_SUCCESS);
672 
673 ppn_error:
674 	vmci_free_kernel_mem(produce_ppns, num_produce_pages *
675 	    sizeof(*produce_ppns));
676 	vmci_free_kernel_mem(consume_ppns, num_consume_pages *
677 	    sizeof(*consume_ppns));
678 	return (VMCI_ERROR_INVALID_ARGS);
679 }
680 
681 /*
682  *------------------------------------------------------------------------------
683  *
684  * vmci_free_ppn_set --
685  *
686  *     Frees the two list of PPNs for a queue pair.
687  *
688  * Results:
689  *     None.
690  *
691  * Side effects:
692  *     None.
693  *
694  *------------------------------------------------------------------------------
695  */
696 
697 void
698 vmci_free_ppn_set(struct ppn_set *ppn_set)
699 {
700 
701 	ASSERT(ppn_set);
702 	if (ppn_set->initialized) {
703 		/* Do not call these functions on NULL inputs. */
704 		ASSERT(ppn_set->produce_ppns && ppn_set->consume_ppns);
705 		vmci_free_kernel_mem(ppn_set->produce_ppns,
706 		    ppn_set->num_produce_pages *
707 		    sizeof(*ppn_set->produce_ppns));
708 		vmci_free_kernel_mem(ppn_set->consume_ppns,
709 		    ppn_set->num_consume_pages *
710 		    sizeof(*ppn_set->consume_ppns));
711 	}
712 	memset(ppn_set, 0, sizeof(*ppn_set));
713 }
714 
715 /*
716  *------------------------------------------------------------------------------
717  *
718  * vmci_populate_ppn_list --
719  *
720  *     Populates the list of PPNs in the hypercall structure with the PPNS
721  *     of the produce queue and the consume queue.
722  *
723  * Results:
724  *     VMCI_SUCCESS.
725  *
726  * Side effects:
727  *     None.
728  *
729  *------------------------------------------------------------------------------
730  */
731 
732 int
733 vmci_populate_ppn_list(uint8_t *call_buf, const struct ppn_set *ppn_set)
734 {
735 
736 	ASSERT(call_buf && ppn_set && ppn_set->initialized);
737 	memcpy(call_buf, ppn_set->produce_ppns,
738 	    ppn_set->num_produce_pages * sizeof(*ppn_set->produce_ppns));
739 	memcpy(call_buf + ppn_set->num_produce_pages *
740 	    sizeof(*ppn_set->produce_ppns), ppn_set->consume_ppns,
741 	    ppn_set->num_consume_pages * sizeof(*ppn_set->consume_ppns));
742 
743 	return (VMCI_SUCCESS);
744 }
745 
746 /*
747  *------------------------------------------------------------------------------
748  *
749  * vmci_memcpy_{to,from}iovec --
750  *
751  *     These helper routines will copy the specified bytes to/from memory that's
752  *     specified as a struct iovec.  The routines can not verify the correctness
753  *     of the struct iovec's contents.
754  *
755  * Results:
756  *      None.
757  *
758  * Side effects:
759  *      None.
760  *
761  *------------------------------------------------------------------------------
762  */
763 
764 static inline void
765 vmci_memcpy_toiovec(struct iovec *iov, uint8_t *src, size_t len)
766 {
767 
768 	while (len > 0) {
769 		if (iov->iov_len) {
770 			size_t to_copy = MIN(iov->iov_len, len);
771 			memcpy(iov->iov_base, src, to_copy);
772 			src += to_copy;
773 			len -= to_copy;
774 			iov->iov_base = (void *)((uintptr_t) iov->iov_base +
775 			    to_copy);
776 			iov->iov_len -= to_copy;
777 		}
778 		iov++;
779 	}
780 }
781 
782 static inline void
783 vmci_memcpy_fromiovec(uint8_t *dst, struct iovec *iov, size_t len)
784 {
785 
786 	while (len > 0) {
787 		if (iov->iov_len) {
788 			size_t to_copy = MIN(iov->iov_len, len);
789 			memcpy(dst, iov->iov_base, to_copy);
790 			dst += to_copy;
791 			len -= to_copy;
792 			iov->iov_base = (void *)((uintptr_t) iov->iov_base +
793 			    to_copy);
794 			iov->iov_len -= to_copy;
795 		}
796 		iov++;
797 	}
798 }
799 
800 /*
801  *------------------------------------------------------------------------------
802  *
803  * __vmci_memcpy_to_queue --
804  *
805  *     Copies from a given buffer or iovector to a VMCI Queue. Assumes that
806  *     offset + size does not wrap around in the queue.
807  *
808  * Results:
809  *     Zero on success, negative error code on failure.
810  *
811  * Side effects:
812  *     None.
813  *
814  *------------------------------------------------------------------------------
815  */
816 
817 #pragma GCC diagnostic ignored "-Wcast-qual"
818 static int
819 __vmci_memcpy_to_queue(struct vmci_queue *queue, uint64_t queue_offset,
820     const void *src, size_t size, bool is_iovec)
821 {
822 	struct vmci_queue_kernel_if *kernel_if = queue->kernel_if;
823 	size_t bytes_copied = 0;
824 
825 	while (bytes_copied < size) {
826 		const uint64_t page_index =
827 		    (queue_offset + bytes_copied) / PAGE_SIZE;
828 		const size_t page_offset =
829 		    (queue_offset + bytes_copied) & (PAGE_SIZE - 1);
830 		void *va;
831 		size_t to_copy;
832 
833 		/* Skip header. */
834 		va = (void *)kernel_if->dmas[page_index + 1].dma_vaddr;
835 
836 		ASSERT(va);
837 		/*
838 		 * Fill up the page if we have enough payload, or else
839 		 * copy the remaining bytes.
840 		 */
841 		to_copy = MIN(PAGE_SIZE - page_offset, size - bytes_copied);
842 
843 		if (is_iovec) {
844 			struct iovec *iov = (struct iovec *)src;
845 
846 			/* The iovec will track bytes_copied internally. */
847 			vmci_memcpy_fromiovec((uint8_t *)va + page_offset,
848 			    iov, to_copy);
849 		} else
850 			memcpy((uint8_t *)va + page_offset,
851 			    (uint8_t *)src + bytes_copied, to_copy);
852 		bytes_copied += to_copy;
853 	}
854 
855 	return (VMCI_SUCCESS);
856 }
857 
858 /*
859  *------------------------------------------------------------------------------
860  *
861  * __vmci_memcpy_from_queue --
862  *
863  *     Copies to a given buffer or iovector from a VMCI Queue. Assumes that
864  *     offset + size does not wrap around in the queue.
865  *
866  * Results:
867  *     Zero on success, negative error code on failure.
868  *
869  * Side effects:
870  *     None.
871  *
872  *------------------------------------------------------------------------------
873  */
874 
875 static int
876 __vmci_memcpy_from_queue(void *dest, const struct vmci_queue *queue,
877     uint64_t queue_offset, size_t size, bool is_iovec)
878 {
879 	struct vmci_queue_kernel_if *kernel_if = queue->kernel_if;
880 	size_t bytes_copied = 0;
881 
882 	while (bytes_copied < size) {
883 		const uint64_t page_index =
884 		    (queue_offset + bytes_copied) / PAGE_SIZE;
885 		const size_t page_offset =
886 		    (queue_offset + bytes_copied) & (PAGE_SIZE - 1);
887 		void *va;
888 		size_t to_copy;
889 
890 		/* Skip header. */
891 		va = (void *)kernel_if->dmas[page_index + 1].dma_vaddr;
892 
893 		ASSERT(va);
894 		/*
895 		 * Fill up the page if we have enough payload, or else
896 		 * copy the remaining bytes.
897 		 */
898 		to_copy = MIN(PAGE_SIZE - page_offset, size - bytes_copied);
899 
900 		if (is_iovec) {
901 			struct iovec *iov = (struct iovec *)dest;
902 
903 			/* The iovec will track bytesCopied internally. */
904 			vmci_memcpy_toiovec(iov, (uint8_t *)va +
905 			    page_offset, to_copy);
906 		} else
907 			memcpy((uint8_t *)dest + bytes_copied,
908 			    (uint8_t *)va + page_offset, to_copy);
909 
910 		bytes_copied += to_copy;
911 	}
912 
913 	return (VMCI_SUCCESS);
914 }
915 
916 /*
917  *------------------------------------------------------------------------------
918  *
919  * vmci_memcpy_to_queue --
920  *
921  *     Copies from a given buffer to a VMCI Queue.
922  *
923  * Results:
924  *     Zero on success, negative error code on failure.
925  *
926  * Side effects:
927  *     None.
928  *
929  *------------------------------------------------------------------------------
930  */
931 
932 int
933 vmci_memcpy_to_queue(struct vmci_queue *queue, uint64_t queue_offset,
934     const void *src, size_t src_offset, size_t size, int buf_type,
935     bool can_block)
936 {
937 
938 	ASSERT(can_block);
939 
940 	return (__vmci_memcpy_to_queue(queue, queue_offset,
941 	    (uint8_t *)src + src_offset, size, false));
942 }
943 
944 /*
945  *------------------------------------------------------------------------------
946  *
947  * vmci_memcpy_from_queue --
948  *
949  *      Copies to a given buffer from a VMCI Queue.
950  *
951  * Results:
952  *      Zero on success, negative error code on failure.
953  *
954  * Side effects:
955  *      None.
956  *
957  *------------------------------------------------------------------------------
958  */
959 
960 int
961 vmci_memcpy_from_queue(void *dest, size_t dest_offset,
962     const struct vmci_queue *queue, uint64_t queue_offset, size_t size,
963     int buf_type, bool can_block)
964 {
965 
966 	ASSERT(can_block);
967 
968 	return (__vmci_memcpy_from_queue((uint8_t *)dest + dest_offset,
969 	    queue, queue_offset, size, false));
970 }
971 
972 /*
973  *------------------------------------------------------------------------------
974  *
975  * vmci_memcpy_to_queue_local --
976  *
977  *     Copies from a given buffer to a local VMCI queue. This is the
978  *     same as a regular copy.
979  *
980  * Results:
981  *     Zero on success, negative error code on failure.
982  *
983  * Side effects:
984  *     None.
985  *
986  *------------------------------------------------------------------------------
987  */
988 
989 int
990 vmci_memcpy_to_queue_local(struct vmci_queue *queue, uint64_t queue_offset,
991     const void *src, size_t src_offset, size_t size, int buf_type,
992     bool can_block)
993 {
994 
995 	ASSERT(can_block);
996 
997 	return (__vmci_memcpy_to_queue(queue, queue_offset,
998 	    (uint8_t *)src + src_offset, size, false));
999 }
1000 
1001 /*
1002  *------------------------------------------------------------------------------
1003  *
1004  * vmci_memcpy_from_queue_local --
1005  *
1006  *     Copies to a given buffer from a VMCI Queue.
1007  *
1008  * Results:
1009  *     Zero on success, negative error code on failure.
1010  *
1011  * Side effects:
1012  *     None.
1013  *
1014  *------------------------------------------------------------------------------
1015  */
1016 
1017 int
1018 vmci_memcpy_from_queue_local(void *dest, size_t dest_offset,
1019     const struct vmci_queue *queue, uint64_t queue_offset, size_t size,
1020     int buf_type, bool can_block)
1021 {
1022 
1023 	ASSERT(can_block);
1024 
1025 	return (__vmci_memcpy_from_queue((uint8_t *)dest + dest_offset,
1026 	    queue, queue_offset, size, false));
1027 }
1028 
1029 /*------------------------------------------------------------------------------
1030  *
1031  * vmci_memcpy_to_queue_v --
1032  *
1033  *     Copies from a given iovec from a VMCI Queue.
1034  *
1035  * Results:
1036  *     Zero on success, negative error code on failure.
1037  *
1038  * Side effects:
1039  *     None.
1040  *
1041  *------------------------------------------------------------------------------
1042  */
1043 
1044 int
1045 vmci_memcpy_to_queue_v(struct vmci_queue *queue, uint64_t queue_offset,
1046     const void *src, size_t src_offset, size_t size, int buf_type,
1047     bool can_block)
1048 {
1049 
1050 	ASSERT(can_block);
1051 
1052 	/*
1053 	 * We ignore src_offset because src is really a struct iovec * and will
1054 	 * maintain offset internally.
1055 	 */
1056 	return (__vmci_memcpy_to_queue(queue, queue_offset, src, size,
1057 	    true));
1058 }
1059 
1060 /*
1061  *------------------------------------------------------------------------------
1062  *
1063  * vmci_memcpy_from_queue_v --
1064  *
1065  *     Copies to a given iovec from a VMCI Queue.
1066  *
1067  * Results:
1068  *     Zero on success, negative error code on failure.
1069  *
1070  * Side effects:
1071  *     None.
1072  *
1073  *------------------------------------------------------------------------------
1074  */
1075 
1076 int
1077 vmci_memcpy_from_queue_v(void *dest, size_t dest_offset,
1078     const struct vmci_queue *queue, uint64_t queue_offset, size_t size,
1079     int buf_type, bool can_block)
1080 {
1081 
1082 	ASSERT(can_block);
1083 
1084 	/*
1085 	 * We ignore dest_offset because dest is really a struct iovec * and
1086 	 * will maintain offset internally.
1087 	 */
1088 	return (__vmci_memcpy_from_queue(dest, queue, queue_offset, size,
1089 	    true));
1090 }
1091 
1092 /*
1093  *------------------------------------------------------------------------------
1094  *
1095  * vmci_read_port_bytes --
1096  *
1097  *     Copy memory from an I/O port to kernel memory.
1098  *
1099  * Results:
1100  *     No results.
1101  *
1102  * Side effects:
1103  *     None.
1104  *
1105  *------------------------------------------------------------------------------
1106  */
1107 
1108 void
1109 vmci_read_port_bytes(vmci_io_handle handle, vmci_io_port port, uint8_t *buffer,
1110     size_t buffer_length)
1111 {
1112 
1113 	insb(port, buffer, buffer_length);
1114 }
1115