summaryrefslogtreecommitdiff
path: root/examples/vhost_xen/xenstore_parse.c
blob: 9441639a32ccee717e2d9b0d77ac8dfb007f6544 (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
/*-
 *   BSD LICENSE
 *
 *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
 *   All rights reserved.
 *
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
 *     * Neither the name of Intel Corporation nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdint.h>
#include <unistd.h>
#include <inttypes.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <xen/sys/gntalloc.h>
#include <xen/sys/gntdev.h>
#include <xen/xen-compat.h>
#if __XEN_LATEST_INTERFACE_VERSION__ < 0x00040200
#include <xs.h>
#else
#include <xenstore.h>
#endif

#include <rte_common.h>
#include <rte_memory.h>
#include <rte_tailq.h>
#include <rte_eal.h>
#include <rte_malloc.h>
#include <rte_string_fns.h>
#include <rte_log.h>
#include <rte_debug.h>

#include "xen_vhost.h"

/* xenstore handle */
static struct xs_handle *xs = NULL;

/* gntdev file descriptor to map grant pages */
static int d_fd = -1;

/*
 *  The grant node format in xenstore for vring/mpool is like:
 *  idx#_rx_vring_gref = "gref1#, gref2#, gref3#"
 *  idx#_mempool_gref  = "gref1#, gref2#, gref3#"
 *  each gref# is the grant reference for a shared page.
 *  In each shared page, we store the grant_node_item items.
 */
struct grant_node_item {
	uint32_t gref;
	uint32_t pfn;
} __attribute__((packed));

int cmdline_parse_etheraddr(void *tk, const char *srcbuf,
	void *res, unsigned ressize);

/* Map grant ref refid at addr_ori*/
static void *
xen_grant_mmap(void *addr_ori, int domid, int refid, uint64_t *pindex)
{
	struct ioctl_gntdev_map_grant_ref arg;
	void *addr = NULL;
	int pg_sz = getpagesize();

	arg.count = 1;
	arg.refs[0].domid = domid;
	arg.refs[0].ref = refid;

	int rv = ioctl(d_fd, IOCTL_GNTDEV_MAP_GRANT_REF, &arg);
	if (rv) {
		RTE_LOG(ERR, XENHOST, "  %s: (%d,%d) %s (ioctl failed)\n", __func__,
				domid, refid, strerror(errno));
		return NULL;
	}

	if (addr_ori == NULL)
		addr = mmap(addr_ori, pg_sz, PROT_READ|PROT_WRITE, MAP_SHARED,
				d_fd, arg.index);
	else
		addr = mmap(addr_ori, pg_sz, PROT_READ|PROT_WRITE, MAP_SHARED | MAP_FIXED,
				d_fd, arg.index);

	if (addr == MAP_FAILED) {
		RTE_LOG(ERR, XENHOST, "  %s: (%d, %d) %s (map failed)\n", __func__,
				domid, refid, strerror(errno));
		return NULL;
	}

	if (pindex)
		*pindex = arg.index;

	return addr;
}

/* Unmap one grant ref, and munmap must be called before this */
static int
xen_unmap_grant_ref(uint64_t index)
{
	struct ioctl_gntdev_unmap_grant_ref arg;
	int rv;

	arg.count = 1;
	arg.index = index;
	rv = ioctl(d_fd, IOCTL_GNTDEV_UNMAP_GRANT_REF, &arg);
	if (rv) {
		RTE_LOG(ERR, XENHOST, "  %s: index 0x%" PRIx64 "unmap failed\n", __func__, index);
		return -1;
	}
	return 0;
}

/*
 * Reserve a virtual address space.
 * On success, returns the pointer. On failure, returns NULL.
 */
static void *
get_xen_virtual(size_t size, size_t page_sz)
{
	void *addr;
	uintptr_t aligned_addr;

	addr = mmap(NULL, size + page_sz, PROT_READ, MAP_SHARED | MAP_ANONYMOUS, -1, 0);
	if (addr == MAP_FAILED) {
		RTE_LOG(ERR, XENHOST, "failed get a virtual area\n");
		return NULL;
	}

	aligned_addr = RTE_ALIGN_CEIL((uintptr_t)addr, page_sz);
	munmap(addr, aligned_addr - (uintptr_t)addr);
	munmap((void *)(aligned_addr + size), page_sz + (uintptr_t)addr - aligned_addr);
	addr = (void *)(aligned_addr);

	return addr;
}

static void
free_xen_virtual(void *addr, size_t size, size_t page_sz __rte_unused)
{
	if (addr)
		munmap(addr, size);
}

/*
 * Returns val str in xenstore.
 * @param path
 *  Full path string for key
 * @return
 *  Pointer to Val str, NULL on failure
 */
static char *
xen_read_node(char *path, uint32_t *len)
{
	char *buf;

	buf = xs_read(xs, XBT_NULL, path, len);
	return buf;
}

static int
cal_pagenum(struct xen_gnt *gnt)
{
	unsigned int i;
	/*
	 * the items in the page are in the format of
	 * gref#,pfn#,...,gref#,pfn#
	 * FIXME, 0 is reserved by system, use it as terminator.
	 */
	for (i = 0; i < (PAGE_PFNNUM) / 2; i++) {
		if (gnt->gref_pfn[i * 2].gref <= 0)
			break;
	}

	return i;
}

/* Frees memory allocated to a grant node */
static void
xen_free_gntnode(struct xen_gntnode *gntnode)
{
	if (gntnode == NULL)
		return;
	if (gntnode->gnt_info)
		free(gntnode->gnt_info);
	free(gntnode);
}

/*
 * Parse a grant node.
 * @param domid
 *  Guest domain id.
 * @param path
 *  Full path string for a grant node, like for the following (key, val) pair
 *  idx#_mempool_gref = "gref#, gref#, gref#"
 *  path = 'local/domain/domid/control/dpdk/idx#_mempool_gref'
 *  gref# is a shared page contain packed (gref,pfn) entries
 * @return
 *  Returns the pointer to xen_gntnode
 */
static struct xen_gntnode *
parse_gntnode(int dom_id, char *path)
{
	char **gref_list = NULL;
	uint32_t i, len, gref_num;
	void *addr = NULL;
	char *buf = NULL;
	struct xen_gntnode *gntnode = NULL;
	struct xen_gnt *gnt = NULL;
	int pg_sz = getpagesize();
	char *end;
	uint64_t index;

	if ((buf = xen_read_node(path, &len)) == NULL)
		goto err;

	gref_list = malloc(MAX_GREF_PER_NODE * sizeof(char *));
	if (gref_list == NULL)
		goto err;

	gref_num = rte_strsplit(buf, len, gref_list, MAX_GREF_PER_NODE,
			XEN_GREF_SPLITTOKEN);
	if (gref_num == 0) {
		RTE_LOG(ERR, XENHOST, "  %s: invalid grant node format\n", __func__);
		goto err;
	}

	gntnode = (struct xen_gntnode *)calloc(1, sizeof(struct xen_gntnode));
	gnt = (struct xen_gnt *)calloc(gref_num, sizeof(struct xen_gnt));
	if (gnt == NULL || gntnode == NULL)
		goto err;

	for (i = 0; i < gref_num; i++) {
		errno = 0;
		gnt[i].gref = strtol(gref_list[i], &end, 0);
		if (errno != 0 || end == NULL || end == gref_list[i] ||
			(*end != '\0' &&  *end != XEN_GREF_SPLITTOKEN)) {
			RTE_LOG(ERR, XENHOST, "  %s: parse grant node item failed\n", __func__);
			goto err;
		}
		addr = xen_grant_mmap(NULL, dom_id, gnt[i].gref, &index);
		if (addr == NULL) {
			RTE_LOG(ERR, XENHOST, "  %s: map gref %u failed\n", __func__, gnt[i].gref);
			goto err;
		}
		RTE_LOG(INFO, XENHOST, "      %s: map gref %u to %p\n", __func__, gnt[i].gref, addr);
		memcpy(gnt[i].gref_pfn, addr, pg_sz);
		if (munmap(addr, pg_sz)) {
			RTE_LOG(INFO, XENHOST, "  %s: unmap gref %u failed\n", __func__, gnt[i].gref);
			goto err;
		}
		if (xen_unmap_grant_ref(index)) {
			RTE_LOG(INFO, XENHOST, "  %s: release gref %u failed\n", __func__, gnt[i].gref);
			goto err;
		}

	}

	gntnode->gnt_num  = gref_num;
	gntnode->gnt_info = gnt;

	free(buf);
	free(gref_list);
	return gntnode;

err:
	if (gnt)
		free(gnt);
	if (gntnode)
		free(gntnode);
	if (gref_list)
		free(gref_list);
	if (buf)
		free(buf);
	return NULL;
}

/*
 * This function maps grant node of vring or mbuf pool to a continous virtual address space,
 * and returns mapped address, pfn array, index array
 * @param gntnode
 *  Pointer to grant node
 * @param domid
 *  Guest domain id
 * @param ppfn
 *  Pointer to pfn array, caller should free this array
 * @param pgs
 *  Pointer to number of pages
 * @param ppindex
 *  Pointer to index array, used to release grefs when to free this node
 * @return
 *  Pointer to mapped virtual address, NULL on failure
 */
static void *
map_gntnode(struct xen_gntnode *gntnode, int domid, uint32_t **ppfn, uint32_t *pgs, uint64_t **ppindex)
{
	struct xen_gnt *gnt;
	uint32_t i, j;
	size_t total_pages = 0;
	void *addr;
	uint32_t *pfn;
	uint64_t *pindex;
	uint32_t pfn_num = 0;
	int pg_sz;

	if (gntnode == NULL)
		return NULL;

	pg_sz = getpagesize();
	for (i = 0; i < gntnode->gnt_num; i++) {
		gnt = gntnode->gnt_info + i;
		total_pages += cal_pagenum(gnt);
	}
	if ((addr = get_xen_virtual(total_pages * pg_sz, pg_sz)) == NULL) {
		RTE_LOG(ERR, XENHOST, "  %s: failed get_xen_virtual\n", __func__);
		return NULL;
	}
	pfn = calloc(total_pages, (size_t)sizeof(uint32_t));
	pindex = calloc(total_pages, (size_t)sizeof(uint64_t));
	if (pfn == NULL || pindex == NULL) {
		free_xen_virtual(addr, total_pages * pg_sz, pg_sz);
		free(pfn);
		free(pindex);
		return NULL;
	}

	RTE_LOG(INFO, XENHOST, "    %s: total pages:%zu, map to [%p, %p]\n", __func__, total_pages, addr, RTE_PTR_ADD(addr, total_pages * pg_sz - 1));
	for (i = 0; i < gntnode->gnt_num; i++) {
		gnt = gntnode->gnt_info + i;
		for (j = 0; j < (PAGE_PFNNUM) / 2; j++) {
			if ((gnt->gref_pfn[j * 2].gref) <= 0)
				goto _end;
			/*alternative: batch map, or through libxc*/
			if (xen_grant_mmap(RTE_PTR_ADD(addr, pfn_num * pg_sz),
					domid,
					gnt->gref_pfn[j * 2].gref,
					&pindex[pfn_num]) == NULL) {
				goto mmap_failed;
			}
			pfn[pfn_num] = gnt->gref_pfn[j * 2 + 1].pfn_num;
			pfn_num++;
		}
	}

mmap_failed:
	if (pfn_num)
		munmap(addr, pfn_num * pg_sz);
	for (i = 0; i < pfn_num; i++) {
		xen_unmap_grant_ref(pindex[i]);
	}
	free(pindex);
	free(pfn);
	return NULL;

_end:
	if (ppindex)
		*ppindex = pindex;
	else
		free(pindex);
	if (ppfn)
		*ppfn = pfn;
	else
		free(pfn);
	if (pgs)
		*pgs = total_pages;

	return addr;
}

static int
parse_mpool_va(struct xen_mempool *mempool)
{
	char path[PATH_MAX] = {0};
	char *buf;
	uint32_t len;
	char *end;
	int ret = -1;

	errno = 0;
	snprintf(path, sizeof(path),
		XEN_VM_ROOTNODE_FMT"/%d_"XEN_GVA_SUFFIX,
		mempool->dom_id, mempool->pool_idx);

	if((buf = xen_read_node(path, &len)) == NULL)
		goto out;
	mempool->gva = (void *)strtoul(buf, &end, 16);
	if (errno != 0 || end == NULL || end == buf || *end != '\0') {
		mempool->gva = NULL;
		goto out;
	}
	ret = 0;
out:
	if (buf)
		free(buf);
	return ret;
}

/*
 * map mbuf pool
 */
static int
map_mempoolnode(struct xen_gntnode *gntnode,
			struct xen_mempool *mempool)
{
	if (gntnode == NULL || mempool == NULL)
		return -1;

	mempool->hva =
		map_gntnode(gntnode, mempool->dom_id, &mempool->mempfn_tbl, &mempool->mempfn_num, &mempool->pindex);

	RTE_LOG(INFO, XENHOST, "  %s: map mempool at %p\n", __func__, (void *)mempool->hva);
	if (mempool->hva)
		return 0;
	else {
		return -1;
	}
}

void
cleanup_mempool(struct xen_mempool *mempool)
{
	int pg_sz = getpagesize();
	uint32_t i;

	if (mempool->hva)
		munmap(mempool->hva, mempool->mempfn_num * pg_sz);
	mempool->hva = NULL;

	if (mempool->pindex) {
		RTE_LOG(INFO, XENHOST, "  %s: unmap dom %02u mempool%02u %u grefs\n",
			__func__,
			mempool->dom_id,
			mempool->pool_idx,
			mempool->mempfn_num);
		for (i = 0; i < mempool->mempfn_num; i ++) {
			xen_unmap_grant_ref(mempool->pindex[i]);
		}
	}
	mempool->pindex = NULL;

	if (mempool->mempfn_tbl)
		free(mempool->mempfn_tbl);
	mempool->mempfn_tbl = NULL;
}

/*
 * process mempool node idx#_mempool_gref, idx = 0, 1, 2...
 * untill we encounter a node that doesn't exist.
 */
int
parse_mempoolnode(struct xen_guest *guest)
{
	uint32_t i, len;
	char path[PATH_MAX] = {0};
	struct xen_gntnode *gntnode = NULL;
	struct xen_mempool *mempool = NULL;
	char *buf;

	bzero(&guest->mempool, MAX_XENVIRT_MEMPOOL * sizeof(guest->mempool[0]));
	guest->pool_num = 0;

	while (1) {
		/* check if null terminated */
		snprintf(path, sizeof(path),
			XEN_VM_ROOTNODE_FMT"/%d_"XEN_MEMPOOL_SUFFIX,
			guest->dom_id,
			guest->pool_num);

		if ((buf = xen_read_node(path, &len)) != NULL) {
			/* this node exists */
			free(buf);
		} else {
			if (guest->pool_num == 0) {
				RTE_LOG(ERR, PMD, "no mempool found\n");
				return -1;
			}
			break;
		}

		mempool = &guest->mempool[guest->pool_num];
		mempool->dom_id = guest->dom_id;
		mempool->pool_idx = guest->pool_num;

		RTE_LOG(INFO, XENHOST, "  %s: mempool %u parse gntnode %s\n", __func__, guest->pool_num, path);
		gntnode = parse_gntnode(guest->dom_id, path);
		if (gntnode == NULL)
			goto err;

		if (parse_mpool_va(mempool))
			goto err;

		RTE_LOG(INFO, XENHOST, "  %s: mempool %u map gntnode %s\n", __func__, guest->pool_num, path);
		if (map_mempoolnode(gntnode, mempool))
			goto err;

		xen_free_gntnode(gntnode);
		guest->pool_num++;
	}

	return 0;
err:
	if (gntnode)
		xen_free_gntnode(gntnode);
	for (i = 0; i <  MAX_XENVIRT_MEMPOOL ; i++) {
		cleanup_mempool(&guest->mempool[i]);
	}
	/* reinitialise mempool */
	bzero(&guest->mempool, MAX_XENVIRT_MEMPOOL * sizeof(guest->mempool[0]));
	return -1;
}

static int
xen_map_vringflag(struct xen_vring *vring)
{
	char path[PATH_MAX] = {0};
	char *buf;
	uint32_t len,gref;
	int pg_sz = getpagesize();
	char *end;

	snprintf(path, sizeof(path),
		XEN_VM_ROOTNODE_FMT"/%d_"XEN_VRINGFLAG_SUFFIX,
		vring->dom_id, vring->virtio_idx);

	if((buf = xen_read_node(path, &len)) == NULL)
		goto err;

	errno = 0;
	gref = strtol(buf, &end, 0);
	if (errno != 0 || end == NULL || end == buf) {
		goto err;
	}
	vring->flag = xen_grant_mmap(0, vring->dom_id, gref, &vring->flag_index);
	if (vring->flag == NULL || *vring->flag == 0)
		goto err;

	free(buf);
	return 0;
err:
	if (buf)
		free(buf);
	if (vring->flag) {
		munmap(vring->flag, pg_sz);
		vring->flag = NULL;
		xen_unmap_grant_ref(vring->flag_index);
	}
	return -1;
}


static int
xen_map_rxvringnode(struct xen_gntnode *gntnode,
				struct xen_vring *vring)
{
	vring->rxvring_addr =
		map_gntnode(gntnode, vring->dom_id, &vring->rxpfn_tbl, &vring->rxpfn_num, &vring->rx_pindex);
	RTE_LOG(INFO, XENHOST, "  %s: map rx vring at %p\n", __func__, (void *)vring->rxvring_addr);
	if (vring->rxvring_addr)
		return 0;
	else
		return -1;
}

static int
xen_map_txvringnode(struct xen_gntnode *gntnode,
				struct xen_vring *vring)
{
	vring->txvring_addr =
		map_gntnode(gntnode, vring->dom_id, &vring->txpfn_tbl, &vring->txpfn_num, &vring->tx_pindex);
	RTE_LOG(INFO, XENHOST, "  %s: map tx vring at %p\n", __func__, (void *)vring->txvring_addr);
	if (vring->txvring_addr)
		return 0;
	else
		return -1;
}

void
cleanup_vring(struct xen_vring *vring)
{
	int pg_sz = getpagesize();
	uint32_t i;

	RTE_LOG(INFO, XENHOST, "  %s: cleanup dom %u vring %u\n", __func__, vring->dom_id, vring->virtio_idx);
	if (vring->rxvring_addr) {
		munmap(vring->rxvring_addr, vring->rxpfn_num * pg_sz);
		RTE_LOG(INFO, XENHOST, "  %s: unmap rx vring [%p, %p]\n",
			__func__,
			vring->rxvring_addr,
			RTE_PTR_ADD(vring->rxvring_addr,
			vring->rxpfn_num * pg_sz - 1));
	}
	vring->rxvring_addr = NULL;


	if (vring->rx_pindex) {
		RTE_LOG(INFO, XENHOST, "  %s: unmap rx vring %u grefs\n", __func__, vring->rxpfn_num);
		for (i = 0; i < vring->rxpfn_num; i++) {
			xen_unmap_grant_ref(vring->rx_pindex[i]);
		}
	}
	vring->rx_pindex = NULL;

	if (vring->rxpfn_tbl)
		free(vring->rxpfn_tbl);
	vring->rxpfn_tbl = NULL;

	if (vring->txvring_addr) {
		munmap(vring->txvring_addr, vring->txpfn_num * pg_sz);
		RTE_LOG(INFO, XENHOST, "  %s: unmap tx vring [%p, %p]\n",
			__func__,
			vring->txvring_addr,
			RTE_PTR_ADD(vring->txvring_addr,
			vring->txpfn_num * pg_sz - 1));
	}
	vring->txvring_addr = NULL;

	if (vring->tx_pindex) {
		RTE_LOG(INFO, XENHOST, "  %s: unmap tx vring %u grefs\n", __func__, vring->txpfn_num);
		for (i = 0; i < vring->txpfn_num; i++) {
			xen_unmap_grant_ref(vring->tx_pindex[i]);
		}
	}
	vring->tx_pindex = NULL;

	if (vring->txpfn_tbl)
		free(vring->txpfn_tbl);
	vring->txpfn_tbl = NULL;

	if (vring->flag) {
		if (!munmap((void *)vring->flag, pg_sz))
			RTE_LOG(INFO, XENHOST, "  %s: unmap flag page at %p\n", __func__, vring->flag);
		if (!xen_unmap_grant_ref(vring->flag_index))
			RTE_LOG(INFO, XENHOST, "  %s: release flag ref index 0x%" PRIx64 "\n", __func__, vring->flag_index);
	}
	vring->flag = NULL;
	return;
}



static int
xen_parse_etheraddr(struct xen_vring *vring)
{
	char path[PATH_MAX] = {0};
	char *buf;
	uint32_t len;
	int ret = -1;

	snprintf(path, sizeof(path),
		XEN_VM_ROOTNODE_FMT"/%d_"XEN_ADDR_SUFFIX,
		vring->dom_id, vring->virtio_idx);

	if ((buf = xen_read_node(path, &len)) == NULL)
		goto out;

	if (cmdline_parse_etheraddr(NULL, buf, &vring->addr,
			sizeof(vring->addr)) < 0)
		goto out;
	ret = 0;
out:
	if (buf)
		free(buf);
	return ret;
}


int
parse_vringnode(struct xen_guest *guest, uint32_t virtio_idx)
{
	char path[PATH_MAX] = {0};
	struct xen_gntnode *rx_gntnode = NULL;
	struct xen_gntnode *tx_gntnode = NULL;
	struct xen_vring *vring = NULL;

	/*check if null terminated */
	snprintf(path, sizeof(path),
		XEN_VM_ROOTNODE_FMT"/%d_"XEN_RXVRING_SUFFIX,
		guest->dom_id,
		virtio_idx);

	RTE_LOG(INFO, XENHOST, "  %s: virtio %u parse rx gntnode %s\n", __func__, virtio_idx, path);
	rx_gntnode = parse_gntnode(guest->dom_id, path);
	if (rx_gntnode == NULL)
		goto err;

	/*check if null terminated */
	snprintf(path, sizeof(path),
		XEN_VM_ROOTNODE_FMT"/%d_"XEN_TXVRING_SUFFIX,
		guest->dom_id,
		virtio_idx);

	RTE_LOG(INFO, XENHOST, "  %s: virtio %u parse tx gntnode %s\n", __func__, virtio_idx, path);
	tx_gntnode = parse_gntnode(guest->dom_id, path);
	if (tx_gntnode == NULL)
		goto err;

	vring = &guest->vring[virtio_idx];
	bzero(vring, sizeof(*vring));
	vring->dom_id = guest->dom_id;
	vring->virtio_idx = virtio_idx;

	if (xen_parse_etheraddr(vring) != 0)
		goto err;

	RTE_LOG(INFO, XENHOST, "  %s: virtio %u map rx gntnode %s\n", __func__, virtio_idx, path);
	if (xen_map_rxvringnode(rx_gntnode, vring) != 0)
		goto err;

	RTE_LOG(INFO, XENHOST, "  %s: virtio %u map tx gntnode %s\n", __func__, virtio_idx, path);
	if (xen_map_txvringnode(tx_gntnode, vring) != 0)
		goto err;

	if (xen_map_vringflag(vring) != 0)
		goto err;

	guest->vring_num++;

	xen_free_gntnode(rx_gntnode);
	xen_free_gntnode(tx_gntnode);

	return 0;

err:
	if (rx_gntnode)
		xen_free_gntnode(rx_gntnode);
	if (tx_gntnode)
		xen_free_gntnode(tx_gntnode);
	if (vring) {
		cleanup_vring(vring);
		bzero(vring, sizeof(*vring));
	}
	return -1;
}

/*
 * Open xen grant dev driver
 * @return
 *  0 on success, -1 on failure.
 */
static int
xen_grant_init(void)
{
	d_fd = open(XEN_GNTDEV_FNAME, O_RDWR);

	return d_fd == -1? (-1): (0);
}

/*
 * Initialise xenstore handle and open grant dev driver.
 * @return
 *  0 on success, -1 on failure.
 */
int
xenhost_init(void)
{
	xs = xs_daemon_open();
	if (xs == NULL) {
		rte_panic("failed initialize xen daemon handler");
		return -1;
	}
	if (xen_grant_init())
		return -1;
	return 0;
}