summaryrefslogtreecommitdiffstats
path: root/drivers/virt/vboxguest/vboxguest_utils.c
blob: 43c391626a000d98bb6461d274cd2317d98e2913 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
/* SPDX-License-Identifier: (GPL-2.0 OR CDDL-1.0) */
/*
 * vboxguest vmm-req and hgcm-call code, VBoxGuestR0LibHGCMInternal.cpp,
 * VBoxGuestR0LibGenericRequest.cpp and RTErrConvertToErrno.cpp in vbox svn.
 *
 * Copyright (C) 2006-2016 Oracle Corporation
 */

#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/sizes.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/vmalloc.h>
#include <linux/vbox_err.h>
#include <linux/vbox_utils.h>
#include "vboxguest_core.h"

/* Get the pointer to the first parameter of a HGCM call request. */
#define VMMDEV_HGCM_CALL_PARMS(a) \
	((struct vmmdev_hgcm_function_parameter *)( \
		(u8 *)(a) + sizeof(struct vmmdev_hgcm_call)))

/* The max parameter buffer size for a user request. */
#define VBG_MAX_HGCM_USER_PARM		(24 * SZ_1M)
/* The max parameter buffer size for a kernel request. */
#define VBG_MAX_HGCM_KERNEL_PARM	(16 * SZ_1M)

#define VBG_DEBUG_PORT			0x504

/* This protects vbg_log_buf and serializes VBG_DEBUG_PORT accesses */
static DEFINE_SPINLOCK(vbg_log_lock);
static char vbg_log_buf[128];

#define VBG_LOG(name, pr_func) \
void name(const char *fmt, ...)						\
{									\
	unsigned long flags;						\
	va_list args;							\
	int i, count;							\
									\
	va_start(args, fmt);						\
	spin_lock_irqsave(&vbg_log_lock, flags);			\
									\
	count = vscnprintf(vbg_log_buf, sizeof(vbg_log_buf), fmt, args);\
	for (i = 0; i < count; i++)					\
		outb(vbg_log_buf[i], VBG_DEBUG_PORT);			\
									\
	pr_func("%s", vbg_log_buf);					\
									\
	spin_unlock_irqrestore(&vbg_log_lock, flags);			\
	va_end(args);							\
}									\
EXPORT_SYMBOL(name)

VBG_LOG(vbg_info, pr_info);
VBG_LOG(vbg_warn, pr_warn);
VBG_LOG(vbg_err, pr_err);
#if defined(DEBUG) && !defined(CONFIG_DYNAMIC_DEBUG)
VBG_LOG(vbg_debug, pr_debug);
#endif

void *vbg_req_alloc(size_t len, enum vmmdev_request_type req_type,
		    u32 requestor)
{
	struct vmmdev_request_header *req;
	int order = get_order(PAGE_ALIGN(len));

	req = (void *)__get_free_pages(GFP_KERNEL | GFP_DMA32, order);
	if (!req)
		return NULL;

	memset(req, 0xaa, len);

	req->size = len;
	req->version = VMMDEV_REQUEST_HEADER_VERSION;
	req->request_type = req_type;
	req->rc = VERR_GENERAL_FAILURE;
	req->reserved1 = 0;
	req->requestor = requestor;

	return req;
}

void vbg_req_free(void *req, size_t len)
{
	if (!req)
		return;

	free_pages((unsigned long)req, get_order(PAGE_ALIGN(len)));
}

/* Note this function returns a VBox status code, not a negative errno!! */
int vbg_req_perform(struct vbg_dev *gdev, void *req)
{
	unsigned long phys_req = virt_to_phys(req);

	outl(phys_req, gdev->io_port + VMMDEV_PORT_OFF_REQUEST);
	/*
	 * The host changes the request as a result of the outl, make sure
	 * the outl and any reads of the req happen in the correct order.
	 */
	mb();

	return ((struct vmmdev_request_header *)req)->rc;
}

static bool hgcm_req_done(struct vbg_dev *gdev,
			  struct vmmdev_hgcmreq_header *header)
{
	unsigned long flags;
	bool done;

	spin_lock_irqsave(&gdev->event_spinlock, flags);
	done = header->flags & VMMDEV_HGCM_REQ_DONE;
	spin_unlock_irqrestore(&gdev->event_spinlock, flags);

	return done;
}

int vbg_hgcm_connect(struct vbg_dev *gdev, u32 requestor,
		     struct vmmdev_hgcm_service_location *loc,
		     u32 *client_id, int *vbox_status)
{
	struct vmmdev_hgcm_connect *hgcm_connect = NULL;
	int rc;

	hgcm_connect = vbg_req_alloc(sizeof(*hgcm_connect),
				     VMMDEVREQ_HGCM_CONNECT, requestor);
	if (!hgcm_connect)
		return -ENOMEM;

	hgcm_connect->header.flags = 0;
	memcpy(&hgcm_connect->loc, loc, sizeof(*loc));
	hgcm_connect->client_id = 0;

	rc = vbg_req_perform(gdev, hgcm_connect);

	if (rc == VINF_HGCM_ASYNC_EXECUTE)
		wait_event(gdev->hgcm_wq,
			   hgcm_req_done(gdev, &hgcm_connect->header));

	if (rc >= 0) {
		*client_id = hgcm_connect->client_id;
		rc = hgcm_connect->header.result;
	}

	vbg_req_free(hgcm_connect, sizeof(*hgcm_connect));

	*vbox_status = rc;
	return 0;
}
EXPORT_SYMBOL(vbg_hgcm_connect);

int vbg_hgcm_disconnect(struct vbg_dev *gdev, u32 requestor,
			u32 client_id, int *vbox_status)
{
	struct vmmdev_hgcm_disconnect *hgcm_disconnect = NULL;
	int rc;

	hgcm_disconnect = vbg_req_alloc(sizeof(*hgcm_disconnect),
					VMMDEVREQ_HGCM_DISCONNECT,
					requestor);
	if (!hgcm_disconnect)
		return -ENOMEM;

	hgcm_disconnect->header.flags = 0;
	hgcm_disconnect->client_id = client_id;

	rc = vbg_req_perform(gdev, hgcm_disconnect);

	if (rc == VINF_HGCM_ASYNC_EXECUTE)
		wait_event(gdev->hgcm_wq,
			   hgcm_req_done(gdev, &hgcm_disconnect->header));

	if (rc >= 0)
		rc = hgcm_disconnect->header.result;

	vbg_req_free(hgcm_disconnect, sizeof(*hgcm_disconnect));

	*vbox_status = rc;
	return 0;
}
EXPORT_SYMBOL(vbg_hgcm_disconnect);

static u32 hgcm_call_buf_size_in_pages(void *buf, u32 len)
{
	u32 size = PAGE_ALIGN(len + ((unsigned long)buf & ~PAGE_MASK));

	return size >> PAGE_SHIFT;
}

static void hgcm_call_add_pagelist_size(void *buf, u32 len, size_t *extra)
{
	u32 page_count;

	page_count = hgcm_call_buf_size_in_pages(buf, len);
	*extra += offsetof(struct vmmdev_hgcm_pagelist, pages[page_count]);
}

static int hgcm_call_preprocess_linaddr(
	const struct vmmdev_hgcm_function_parameter *src_parm,
	void **bounce_buf_ret, size_t *extra)
{
	void *buf, *bounce_buf;
	bool copy_in;
	u32 len;
	int ret;

	buf = (void *)src_parm->u.pointer.u.linear_addr;
	len = src_parm->u.pointer.size;
	copy_in = src_parm->type != VMMDEV_HGCM_PARM_TYPE_LINADDR_OUT;

	if (len > VBG_MAX_HGCM_USER_PARM)
		return -E2BIG;

	bounce_buf = kvmalloc(len, GFP_KERNEL);
	if (!bounce_buf)
		return -ENOMEM;

	*bounce_buf_ret = bounce_buf;

	if (copy_in) {
		ret = copy_from_user(bounce_buf, (void __user *)buf, len);
		if (ret)
			return -EFAULT;
	} else {
		memset(bounce_buf, 0, len);
	}

	hgcm_call_add_pagelist_size(bounce_buf, len, extra);
	return 0;
}

/**
 * Preprocesses the HGCM call, validate parameters, alloc bounce buffers and
 * figure out how much extra storage we need for page lists.
 * Return: 0 or negative errno value.
 * @src_parm:         Pointer to source function call parameters
 * @parm_count:       Number of function call parameters.
 * @bounce_bufs_ret:  Where to return the allocated bouncebuffer array
 * @extra:            Where to return the extra request space needed for
 *                    physical page lists.
 */
static int hgcm_call_preprocess(
	const struct vmmdev_hgcm_function_parameter *src_parm,
	u32 parm_count, void ***bounce_bufs_ret, size_t *extra)
{
	void *buf, **bounce_bufs = NULL;
	u32 i, len;
	int ret;

	for (i = 0; i < parm_count; i++, src_parm++) {
		switch (src_parm->type) {
		case VMMDEV_HGCM_PARM_TYPE_32BIT:
		case VMMDEV_HGCM_PARM_TYPE_64BIT:
			break;

		case VMMDEV_HGCM_PARM_TYPE_LINADDR:
		case VMMDEV_HGCM_PARM_TYPE_LINADDR_IN:
		case VMMDEV_HGCM_PARM_TYPE_LINADDR_OUT:
			if (!bounce_bufs) {
				bounce_bufs = kcalloc(parm_count,
						      sizeof(void *),
						      GFP_KERNEL);
				if (!bounce_bufs)
					return -ENOMEM;

				*bounce_bufs_ret = bounce_bufs;
			}

			ret = hgcm_call_preprocess_linaddr(src_parm,
							   &bounce_bufs[i],
							   extra);
			if (ret)
				return ret;

			break;

		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL:
		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL_IN:
		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL_OUT:
			buf = (void *)src_parm->u.pointer.u.linear_addr;
			len = src_parm->u.pointer.size;
			if (WARN_ON(len > VBG_MAX_HGCM_KERNEL_PARM))
				return -E2BIG;

			hgcm_call_add_pagelist_size(buf, len, extra);
			break;

		default:
			return -EINVAL;
		}
	}

	return 0;
}

/**
 * Translates linear address types to page list direction flags.
 *
 * Return: page list flags.
 * @type:  The type.
 */
static u32 hgcm_call_linear_addr_type_to_pagelist_flags(
	enum vmmdev_hgcm_function_parameter_type type)
{
	switch (type) {
	default:
		WARN_ON(1);
		/* Fall through */
	case VMMDEV_HGCM_PARM_TYPE_LINADDR:
	case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL:
		return VMMDEV_HGCM_F_PARM_DIRECTION_BOTH;

	case VMMDEV_HGCM_PARM_TYPE_LINADDR_IN:
	case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL_IN:
		return VMMDEV_HGCM_F_PARM_DIRECTION_TO_HOST;

	case VMMDEV_HGCM_PARM_TYPE_LINADDR_OUT:
	case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL_OUT:
		return VMMDEV_HGCM_F_PARM_DIRECTION_FROM_HOST;
	}
}

static void hgcm_call_init_linaddr(struct vmmdev_hgcm_call *call,
	struct vmmdev_hgcm_function_parameter *dst_parm, void *buf, u32 len,
	enum vmmdev_hgcm_function_parameter_type type, u32 *off_extra)
{
	struct vmmdev_hgcm_pagelist *dst_pg_lst;
	struct page *page;
	bool is_vmalloc;
	u32 i, page_count;

	dst_parm->type = type;

	if (len == 0) {
		dst_parm->u.pointer.size = 0;
		dst_parm->u.pointer.u.linear_addr = 0;
		return;
	}

	dst_pg_lst = (void *)call + *off_extra;
	page_count = hgcm_call_buf_size_in_pages(buf, len);
	is_vmalloc = is_vmalloc_addr(buf);

	dst_parm->type = VMMDEV_HGCM_PARM_TYPE_PAGELIST;
	dst_parm->u.page_list.size = len;
	dst_parm->u.page_list.offset = *off_extra;
	dst_pg_lst->flags = hgcm_call_linear_addr_type_to_pagelist_flags(type);
	dst_pg_lst->offset_first_page = (unsigned long)buf & ~PAGE_MASK;
	dst_pg_lst->page_count = page_count;

	for (i = 0; i < page_count; i++) {
		if (is_vmalloc)
			page = vmalloc_to_page(buf);
		else
			page = virt_to_page(buf);

		dst_pg_lst->pages[i] = page_to_phys(page);
		buf += PAGE_SIZE;
	}

	*off_extra += offsetof(struct vmmdev_hgcm_pagelist, pages[page_count]);
}

/**
 * Initializes the call request that we're sending to the host.
 * @call:            The call to initialize.
 * @client_id:       The client ID of the caller.
 * @function:        The function number of the function to call.
 * @src_parm:        Pointer to source function call parameters.
 * @parm_count:      Number of function call parameters.
 * @bounce_bufs:     The bouncebuffer array.
 */
static void hgcm_call_init_call(
	struct vmmdev_hgcm_call *call, u32 client_id, u32 function,
	const struct vmmdev_hgcm_function_parameter *src_parm,
	u32 parm_count, void **bounce_bufs)
{
	struct vmmdev_hgcm_function_parameter *dst_parm =
		VMMDEV_HGCM_CALL_PARMS(call);
	u32 i, off_extra = (uintptr_t)(dst_parm + parm_count) - (uintptr_t)call;
	void *buf;

	call->header.flags = 0;
	call->header.result = VINF_SUCCESS;
	call->client_id = client_id;
	call->function = function;
	call->parm_count = parm_count;

	for (i = 0; i < parm_count; i++, src_parm++, dst_parm++) {
		switch (src_parm->type) {
		case VMMDEV_HGCM_PARM_TYPE_32BIT:
		case VMMDEV_HGCM_PARM_TYPE_64BIT:
			*dst_parm = *src_parm;
			break;

		case VMMDEV_HGCM_PARM_TYPE_LINADDR:
		case VMMDEV_HGCM_PARM_TYPE_LINADDR_IN:
		case VMMDEV_HGCM_PARM_TYPE_LINADDR_OUT:
			hgcm_call_init_linaddr(call, dst_parm, bounce_bufs[i],
					       src_parm->u.pointer.size,
					       src_parm->type, &off_extra);
			break;

		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL:
		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL_IN:
		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL_OUT:
			buf = (void *)src_parm->u.pointer.u.linear_addr;
			hgcm_call_init_linaddr(call, dst_parm, buf,
					       src_parm->u.pointer.size,
					       src_parm->type, &off_extra);
			break;

		default:
			WARN_ON(1);
			dst_parm->type = VMMDEV_HGCM_PARM_TYPE_INVALID;
		}
	}
}

/**
 * Tries to cancel a pending HGCM call.
 *
 * Return: VBox status code
 */
static int hgcm_cancel_call(struct vbg_dev *gdev, struct vmmdev_hgcm_call *call)
{
	int rc;

	/*
	 * We use a pre-allocated request for cancellations, which is
	 * protected by cancel_req_mutex. This means that all cancellations
	 * get serialized, this should be fine since they should be rare.
	 */
	mutex_lock(&gdev->cancel_req_mutex);
	gdev->cancel_req->phys_req_to_cancel = virt_to_phys(call);
	rc = vbg_req_perform(gdev, gdev->cancel_req);
	mutex_unlock(&gdev->cancel_req_mutex);

	if (rc == VERR_NOT_IMPLEMENTED) {
		call->header.flags |= VMMDEV_HGCM_REQ_CANCELLED;
		call->header.header.request_type = VMMDEVREQ_HGCM_CANCEL;

		rc = vbg_req_perform(gdev, call);
		if (rc == VERR_INVALID_PARAMETER)
			rc = VERR_NOT_FOUND;
	}

	if (rc >= 0)
		call->header.flags |= VMMDEV_HGCM_REQ_CANCELLED;

	return rc;
}

/**
 * Performs the call and completion wait.
 * Return: 0 or negative errno value.
 * @gdev:        The VBoxGuest device extension.
 * @call:        The call to execute.
 * @timeout_ms:  Timeout in ms.
 * @leak_it:     Where to return the leak it / free it, indicator.
 *               Cancellation fun.
 */
static int vbg_hgcm_do_call(struct vbg_dev *gdev, struct vmmdev_hgcm_call *call,
			    u32 timeout_ms, bool *leak_it)
{
	int rc, cancel_rc, ret;
	long timeout;

	*leak_it = false;

	rc = vbg_req_perform(gdev, call);

	/*
	 * If the call failed, then pretend success. Upper layers will
	 * interpret the result code in the packet.
	 */
	if (rc < 0) {
		call->header.result = rc;
		return 0;
	}

	if (rc != VINF_HGCM_ASYNC_EXECUTE)
		return 0;

	/* Host decided to process the request asynchronously, wait for it */
	if (timeout_ms == U32_MAX)
		timeout = MAX_SCHEDULE_TIMEOUT;
	else
		timeout = msecs_to_jiffies(timeout_ms);

	timeout = wait_event_interruptible_timeout(
					gdev->hgcm_wq,
					hgcm_req_done(gdev, &call->header),
					timeout);

	/* timeout > 0 means hgcm_req_done has returned true, so success */
	if (timeout > 0)
		return 0;

	if (timeout == 0)
		ret = -ETIMEDOUT;
	else
		ret = -EINTR;

	/* Cancel the request */
	cancel_rc = hgcm_cancel_call(gdev, call);
	if (cancel_rc >= 0)
		return ret;

	/*
	 * Failed to cancel, this should mean that the cancel has lost the
	 * race with normal completion, wait while the host completes it.
	 */
	if (cancel_rc == VERR_NOT_FOUND || cancel_rc == VERR_SEM_DESTROYED)
		timeout = msecs_to_jiffies(500);
	else
		timeout = msecs_to_jiffies(2000);

	timeout = wait_event_timeout(gdev->hgcm_wq,
				     hgcm_req_done(gdev, &call->header),
				     timeout);

	if (WARN_ON(timeout == 0)) {
		/* We really should never get here */
		vbg_err("%s: Call timedout and cancellation failed, leaking the request\n",
			__func__);
		*leak_it = true;
		return ret;
	}

	/* The call has completed normally after all */
	return 0;
}

/**
 * Copies the result of the call back to the caller info structure and user
 * buffers.
 * Return: 0 or negative errno value.
 * @call:            HGCM call request.
 * @dst_parm:        Pointer to function call parameters destination.
 * @parm_count:      Number of function call parameters.
 * @bounce_bufs:     The bouncebuffer array.
 */
static int hgcm_call_copy_back_result(
	const struct vmmdev_hgcm_call *call,
	struct vmmdev_hgcm_function_parameter *dst_parm,
	u32 parm_count, void **bounce_bufs)
{
	const struct vmmdev_hgcm_function_parameter *src_parm =
		VMMDEV_HGCM_CALL_PARMS(call);
	void __user *p;
	int ret;
	u32 i;

	/* Copy back parameters. */
	for (i = 0; i < parm_count; i++, src_parm++, dst_parm++) {
		switch (dst_parm->type) {
		case VMMDEV_HGCM_PARM_TYPE_32BIT:
		case VMMDEV_HGCM_PARM_TYPE_64BIT:
			*dst_parm = *src_parm;
			break;

		case VMMDEV_HGCM_PARM_TYPE_PAGELIST:
			dst_parm->u.page_list.size = src_parm->u.page_list.size;
			break;

		case VMMDEV_HGCM_PARM_TYPE_LINADDR_IN:
		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL:
		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL_IN:
		case VMMDEV_HGCM_PARM_TYPE_LINADDR_KERNEL_OUT:
			dst_parm->u.pointer.size = src_parm->u.pointer.size;
			break;

		case VMMDEV_HGCM_PARM_TYPE_LINADDR:
		case VMMDEV_HGCM_PARM_TYPE_LINADDR_OUT:
			dst_parm->u.pointer.size = src_parm->u.pointer.size;

			p = (void __user *)dst_parm->u.pointer.u.linear_addr;
			ret = copy_to_user(p, bounce_bufs[i],
					   min(src_parm->u.pointer.size,
					       dst_parm->u.pointer.size));
			if (ret)
				return -EFAULT;
			break;

		default:
			WARN_ON(1);
			return -EINVAL;
		}
	}

	return 0;
}

int vbg_hgcm_call(struct vbg_dev *gdev, u32 requestor, u32 client_id,
		  u32 function, u32 timeout_ms,
		  struct vmmdev_hgcm_function_parameter *parms, u32 parm_count,
		  int *vbox_status)
{
	struct vmmdev_hgcm_call *call;
	void **bounce_bufs = NULL;
	bool leak_it;
	size_t size;
	int i, ret;

	size = sizeof(struct vmmdev_hgcm_call) +
		   parm_count * sizeof(struct vmmdev_hgcm_function_parameter);
	/*
	 * Validate and buffer the parameters for the call. This also increases
	 * call_size with the amount of extra space needed for page lists.
	 */
	ret = hgcm_call_preprocess(parms, parm_count, &bounce_bufs, &size);
	if (ret) {
		/* Even on error bounce bufs may still have been allocated */
		goto free_bounce_bufs;
	}

	call = vbg_req_alloc(size, VMMDEVREQ_HGCM_CALL, requestor);
	if (!call) {
		ret = -ENOMEM;
		goto free_bounce_bufs;
	}

	hgcm_call_init_call(call, client_id, function, parms, parm_count,
			    bounce_bufs);

	ret = vbg_hgcm_do_call(gdev, call, timeout_ms, &leak_it);
	if (ret == 0) {
		*vbox_status = call->header.result;
		ret = hgcm_call_copy_back_result(call, parms, parm_count,
						 bounce_bufs);
	}

	if (!leak_it)
		vbg_req_free(call, size);

free_bounce_bufs:
	if (bounce_bufs) {
		for (i = 0; i < parm_count; i++)
			kvfree(bounce_bufs[i]);
		kfree(bounce_bufs);
	}

	return ret;
}
EXPORT_SYMBOL(vbg_hgcm_call);

#ifdef CONFIG_COMPAT
int vbg_hgcm_call32(
	struct vbg_dev *gdev, u32 requestor, u32 client_id, u32 function,
	u32 timeout_ms, struct vmmdev_hgcm_function_parameter32 *parm32,
	u32 parm_count, int *vbox_status)
{
	struct vmmdev_hgcm_function_parameter *parm64 = NULL;
	u32 i, size;
	int ret = 0;

	/* KISS allocate a temporary request and convert the parameters. */
	size = parm_count * sizeof(struct vmmdev_hgcm_function_parameter);
	parm64 = kzalloc(size, GFP_KERNEL);
	if (!parm64)
		return -ENOMEM;

	for (i = 0; i < parm_count; i++) {
		switch (parm32[i].type) {
		case VMMDEV_HGCM_PARM_TYPE_32BIT:
			parm64[i].type = VMMDEV_HGCM_PARM_TYPE_32BIT;
			parm64[i].u.value32 = parm32[i].u.value32;
			break;

		case VMMDEV_HGCM_PARM_TYPE_64BIT:
			parm64[i].type = VMMDEV_HGCM_PARM_TYPE_64BIT;
			parm64[i].u.value64 = parm32[i].u.value64;
			break;

		case VMMDEV_HGCM_PARM_TYPE_LINADDR_OUT:
		case VMMDEV_HGCM_PARM_TYPE_LINADDR:
		case VMMDEV_HGCM_PARM_TYPE_LINADDR_IN:
			parm64[i].type = parm32[i].type;
			parm64[i].u.pointer.size = parm32[i].u.pointer.size;
			parm64[i].u.pointer.u.linear_addr =
			    parm32[i].u.pointer.u.linear_addr;
			break;

		default:
			ret = -EINVAL;
		}
		if (ret < 0)
			goto out_free;
	}

	ret = vbg_hgcm_call(gdev, requestor, client_id, function, timeout_ms,
			    parm64, parm_count, vbox_status);
	if (ret < 0)
		goto out_free;

	/* Copy back. */
	for (i = 0; i < parm_count; i++, parm32++, parm64++) {
		switch (parm64[i].type) {
		case VMMDEV_HGCM_PARM_TYPE_32BIT:
			parm32[i].u.value32 = parm64[i].u.value32;
			break;

		case VMMDEV_HGCM_PARM_TYPE_64BIT:
			parm32[i].u.value64 = parm64[i].u.value64;
			break;

		case VMMDEV_HGCM_PARM_TYPE_LINADDR_OUT:
		case VMMDEV_HGCM_PARM_TYPE_LINADDR:
		case VMMDEV_HGCM_PARM_TYPE_LINADDR_IN:
			parm32[i].u.pointer.size = parm64[i].u.pointer.size;
			break;

		default:
			WARN_ON(1);
			ret = -EINVAL;
		}
	}

out_free:
	kfree(parm64);
	return ret;
}
#endif

static const int vbg_status_code_to_errno_table[] = {
	[-VERR_ACCESS_DENIED]                            = -EPERM,
	[-VERR_FILE_NOT_FOUND]                           = -ENOENT,
	[-VERR_PROCESS_NOT_FOUND]                        = -ESRCH,
	[-VERR_INTERRUPTED]                              = -EINTR,
	[-VERR_DEV_IO_ERROR]                             = -EIO,
	[-VERR_TOO_MUCH_DATA]                            = -E2BIG,
	[-VERR_BAD_EXE_FORMAT]                           = -ENOEXEC,
	[-VERR_INVALID_HANDLE]                           = -EBADF,
	[-VERR_TRY_AGAIN]                                = -EAGAIN,
	[-VERR_NO_MEMORY]                                = -ENOMEM,
	[-VERR_INVALID_POINTER]                          = -EFAULT,
	[-VERR_RESOURCE_BUSY]                            = -EBUSY,
	[-VERR_ALREADY_EXISTS]                           = -EEXIST,
	[-VERR_NOT_SAME_DEVICE]                          = -EXDEV,
	[-VERR_NOT_A_DIRECTORY]                          = -ENOTDIR,
	[-VERR_PATH_NOT_FOUND]                           = -ENOTDIR,
	[-VERR_INVALID_NAME]                             = -ENOENT,
	[-VERR_IS_A_DIRECTORY]                           = -EISDIR,
	[-VERR_INVALID_PARAMETER]                        = -EINVAL,
	[-VERR_TOO_MANY_OPEN_FILES]                      = -ENFILE,
	[-VERR_INVALID_FUNCTION]                         = -ENOTTY,
	[-VERR_SHARING_VIOLATION]                        = -ETXTBSY,
	[-VERR_FILE_TOO_BIG]                             = -EFBIG,
	[-VERR_DISK_FULL]                                = -ENOSPC,
	[-VERR_SEEK_ON_DEVICE]                           = -ESPIPE,
	[-VERR_WRITE_PROTECT]                            = -EROFS,
	[-VERR_BROKEN_PIPE]                              = -EPIPE,
	[-VERR_DEADLOCK]                                 = -EDEADLK,
	[-VERR_FILENAME_TOO_LONG]                        = -ENAMETOOLONG,
	[-VERR_FILE_LOCK_FAILED]                         = -ENOLCK,
	[-VERR_NOT_IMPLEMENTED]                          = -ENOSYS,
	[-VERR_NOT_SUPPORTED]                            = -ENOSYS,
	[-VERR_DIR_NOT_EMPTY]                            = -ENOTEMPTY,
	[-VERR_TOO_MANY_SYMLINKS]                        = -ELOOP,
	[-VERR_NO_MORE_FILES]				 = -ENODATA,
	[-VERR_NO_DATA]                                  = -ENODATA,
	[-VERR_NET_NO_NETWORK]                           = -ENONET,
	[-VERR_NET_NOT_UNIQUE_NAME]                      = -ENOTUNIQ,
	[-VERR_NO_TRANSLATION]                           = -EILSEQ,
	[-VERR_NET_NOT_SOCKET]                           = -ENOTSOCK,
	[-VERR_NET_DEST_ADDRESS_REQUIRED]                = -EDESTADDRREQ,
	[-VERR_NET_MSG_SIZE]                             = -EMSGSIZE,
	[-VERR_NET_PROTOCOL_TYPE]                        = -EPROTOTYPE,
	[-VERR_NET_PROTOCOL_NOT_AVAILABLE]               = -ENOPROTOOPT,
	[-VERR_NET_PROTOCOL_NOT_SUPPORTED]               = -EPROTONOSUPPORT,
	[-VERR_NET_SOCKET_TYPE_NOT_SUPPORTED]            = -ESOCKTNOSUPPORT,
	[-VERR_NET_OPERATION_NOT_SUPPORTED]              = -EOPNOTSUPP,
	[-VERR_NET_PROTOCOL_FAMILY_NOT_SUPPORTED]        = -EPFNOSUPPORT,
	[-VERR_NET_ADDRESS_FAMILY_NOT_SUPPORTED]         = -EAFNOSUPPORT,
	[-VERR_NET_ADDRESS_IN_USE]                       = -EADDRINUSE,
	[-VERR_NET_ADDRESS_NOT_AVAILABLE]                = -EADDRNOTAVAIL,
	[-VERR_NET_DOWN]                                 = -ENETDOWN,
	[-VERR_NET_UNREACHABLE]                          = -ENETUNREACH,
	[-VERR_NET_CONNECTION_RESET]                     = -ENETRESET,
	[-VERR_NET_CONNECTION_ABORTED]                   = -ECONNABORTED,
	[-VERR_NET_CONNECTION_RESET_BY_PEER]             = -ECONNRESET,
	[-VERR_NET_NO_BUFFER_SPACE]                      = -ENOBUFS,
	[-VERR_NET_ALREADY_CONNECTED]                    = -EISCONN,
	[-VERR_NET_NOT_CONNECTED]                        = -ENOTCONN,
	[-VERR_NET_SHUTDOWN]                             = -ESHUTDOWN,
	[-VERR_NET_TOO_MANY_REFERENCES]                  = -ETOOMANYREFS,
	[-VERR_TIMEOUT]                                  = -ETIMEDOUT,
	[-VERR_NET_CONNECTION_REFUSED]                   = -ECONNREFUSED,
	[-VERR_NET_HOST_DOWN]                            = -EHOSTDOWN,
	[-VERR_NET_HOST_UNREACHABLE]                     = -EHOSTUNREACH,
	[-VERR_NET_ALREADY_IN_PROGRESS]                  = -EALREADY,
	[-VERR_NET_IN_PROGRESS]                          = -EINPROGRESS,
	[-VERR_MEDIA_NOT_PRESENT]                        = -ENOMEDIUM,
	[-VERR_MEDIA_NOT_RECOGNIZED]                     = -EMEDIUMTYPE,
};

int vbg_status_code_to_errno(int rc)
{
	if (rc >= 0)
		return 0;

	rc = -rc;
	if (rc >= ARRAY_SIZE(vbg_status_code_to_errno_table) ||
	    vbg_status_code_to_errno_table[rc] == 0) {
		vbg_warn("%s: Unhandled err %d\n", __func__, -rc);
		return -EPROTO;
	}

	return vbg_status_code_to_errno_table[rc];
}
EXPORT_SYMBOL(vbg_status_code_to_errno);