summaryrefslogtreecommitdiff
path: root/tools/testing/selftests/bpf/xsk.c
blob: d9fb2b730a2cdded37e9c83e50caf81a0134b12c (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
// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)

/*
 * AF_XDP user-space access library.
 *
 * Copyright(c) 2018 - 2019 Intel Corporation.
 *
 * Author(s): Magnus Karlsson <magnus.karlsson@intel.com>
 */

#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <asm/barrier.h>
#include <linux/compiler.h>
#include <linux/ethtool.h>
#include <linux/filter.h>
#include <linux/if_ether.h>
#include <linux/if_link.h>
#include <linux/if_packet.h>
#include <linux/if_xdp.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/sockios.h>
#include <net/if.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/socket.h>
#include <sys/types.h>

#include <bpf/bpf.h>
#include <bpf/libbpf.h>
#include "xsk.h"
#include "bpf_util.h"

#ifndef SOL_XDP
 #define SOL_XDP 283
#endif

#ifndef AF_XDP
 #define AF_XDP 44
#endif

#ifndef PF_XDP
 #define PF_XDP AF_XDP
#endif

#define pr_warn(fmt, ...) fprintf(stderr, fmt, ##__VA_ARGS__)

#define XSKMAP_SIZE 1

struct xsk_umem {
	struct xsk_ring_prod *fill_save;
	struct xsk_ring_cons *comp_save;
	char *umem_area;
	struct xsk_umem_config config;
	int fd;
	int refcount;
	struct list_head ctx_list;
	bool rx_ring_setup_done;
	bool tx_ring_setup_done;
};

struct xsk_ctx {
	struct xsk_ring_prod *fill;
	struct xsk_ring_cons *comp;
	__u32 queue_id;
	struct xsk_umem *umem;
	int refcount;
	int ifindex;
	struct list_head list;
};

struct xsk_socket {
	struct xsk_ring_cons *rx;
	struct xsk_ring_prod *tx;
	struct xsk_ctx *ctx;
	struct xsk_socket_config config;
	int fd;
};

struct nl_mtu_req {
	struct nlmsghdr nh;
	struct ifinfomsg msg;
	char             buf[512];
};

int xsk_umem__fd(const struct xsk_umem *umem)
{
	return umem ? umem->fd : -EINVAL;
}

int xsk_socket__fd(const struct xsk_socket *xsk)
{
	return xsk ? xsk->fd : -EINVAL;
}

static bool xsk_page_aligned(void *buffer)
{
	unsigned long addr = (unsigned long)buffer;

	return !(addr & (getpagesize() - 1));
}

static void xsk_set_umem_config(struct xsk_umem_config *cfg,
				const struct xsk_umem_config *usr_cfg)
{
	if (!usr_cfg) {
		cfg->fill_size = XSK_RING_PROD__DEFAULT_NUM_DESCS;
		cfg->comp_size = XSK_RING_CONS__DEFAULT_NUM_DESCS;
		cfg->frame_size = XSK_UMEM__DEFAULT_FRAME_SIZE;
		cfg->frame_headroom = XSK_UMEM__DEFAULT_FRAME_HEADROOM;
		cfg->flags = XSK_UMEM__DEFAULT_FLAGS;
		return;
	}

	cfg->fill_size = usr_cfg->fill_size;
	cfg->comp_size = usr_cfg->comp_size;
	cfg->frame_size = usr_cfg->frame_size;
	cfg->frame_headroom = usr_cfg->frame_headroom;
	cfg->flags = usr_cfg->flags;
}

static int xsk_set_xdp_socket_config(struct xsk_socket_config *cfg,
				     const struct xsk_socket_config *usr_cfg)
{
	if (!usr_cfg) {
		cfg->rx_size = XSK_RING_CONS__DEFAULT_NUM_DESCS;
		cfg->tx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS;
		cfg->bind_flags = 0;
		return 0;
	}

	cfg->rx_size = usr_cfg->rx_size;
	cfg->tx_size = usr_cfg->tx_size;
	cfg->bind_flags = usr_cfg->bind_flags;

	return 0;
}

static int xsk_get_mmap_offsets(int fd, struct xdp_mmap_offsets *off)
{
	socklen_t optlen;
	int err;

	optlen = sizeof(*off);
	err = getsockopt(fd, SOL_XDP, XDP_MMAP_OFFSETS, off, &optlen);
	if (err)
		return err;

	if (optlen == sizeof(*off))
		return 0;

	return -EINVAL;
}

static int xsk_create_umem_rings(struct xsk_umem *umem, int fd,
				 struct xsk_ring_prod *fill,
				 struct xsk_ring_cons *comp)
{
	struct xdp_mmap_offsets off;
	void *map;
	int err;

	err = setsockopt(fd, SOL_XDP, XDP_UMEM_FILL_RING,
			 &umem->config.fill_size,
			 sizeof(umem->config.fill_size));
	if (err)
		return -errno;

	err = setsockopt(fd, SOL_XDP, XDP_UMEM_COMPLETION_RING,
			 &umem->config.comp_size,
			 sizeof(umem->config.comp_size));
	if (err)
		return -errno;

	err = xsk_get_mmap_offsets(fd, &off);
	if (err)
		return -errno;

	map = mmap(NULL, off.fr.desc + umem->config.fill_size * sizeof(__u64),
		   PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, fd,
		   XDP_UMEM_PGOFF_FILL_RING);
	if (map == MAP_FAILED)
		return -errno;

	fill->mask = umem->config.fill_size - 1;
	fill->size = umem->config.fill_size;
	fill->producer = map + off.fr.producer;
	fill->consumer = map + off.fr.consumer;
	fill->flags = map + off.fr.flags;
	fill->ring = map + off.fr.desc;
	fill->cached_cons = umem->config.fill_size;

	map = mmap(NULL, off.cr.desc + umem->config.comp_size * sizeof(__u64),
		   PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, fd,
		   XDP_UMEM_PGOFF_COMPLETION_RING);
	if (map == MAP_FAILED) {
		err = -errno;
		goto out_mmap;
	}

	comp->mask = umem->config.comp_size - 1;
	comp->size = umem->config.comp_size;
	comp->producer = map + off.cr.producer;
	comp->consumer = map + off.cr.consumer;
	comp->flags = map + off.cr.flags;
	comp->ring = map + off.cr.desc;

	return 0;

out_mmap:
	munmap(map, off.fr.desc + umem->config.fill_size * sizeof(__u64));
	return err;
}

int xsk_umem__create(struct xsk_umem **umem_ptr, void *umem_area,
		     __u64 size, struct xsk_ring_prod *fill,
		     struct xsk_ring_cons *comp,
		     const struct xsk_umem_config *usr_config)
{
	struct xdp_umem_reg mr;
	struct xsk_umem *umem;
	int err;

	if (!umem_area || !umem_ptr || !fill || !comp)
		return -EFAULT;
	if (!size && !xsk_page_aligned(umem_area))
		return -EINVAL;

	umem = calloc(1, sizeof(*umem));
	if (!umem)
		return -ENOMEM;

	umem->fd = socket(AF_XDP, SOCK_RAW | SOCK_CLOEXEC, 0);
	if (umem->fd < 0) {
		err = -errno;
		goto out_umem_alloc;
	}

	umem->umem_area = umem_area;
	INIT_LIST_HEAD(&umem->ctx_list);
	xsk_set_umem_config(&umem->config, usr_config);

	memset(&mr, 0, sizeof(mr));
	mr.addr = (uintptr_t)umem_area;
	mr.len = size;
	mr.chunk_size = umem->config.frame_size;
	mr.headroom = umem->config.frame_headroom;
	mr.flags = umem->config.flags;

	err = setsockopt(umem->fd, SOL_XDP, XDP_UMEM_REG, &mr, sizeof(mr));
	if (err) {
		err = -errno;
		goto out_socket;
	}

	err = xsk_create_umem_rings(umem, umem->fd, fill, comp);
	if (err)
		goto out_socket;

	umem->fill_save = fill;
	umem->comp_save = comp;
	*umem_ptr = umem;
	return 0;

out_socket:
	close(umem->fd);
out_umem_alloc:
	free(umem);
	return err;
}

bool xsk_is_in_mode(u32 ifindex, int mode)
{
	LIBBPF_OPTS(bpf_xdp_query_opts, opts);
	int ret;

	ret = bpf_xdp_query(ifindex, mode, &opts);
	if (ret) {
		printf("XDP mode query returned error %s\n", strerror(errno));
		return false;
	}

	if (mode == XDP_FLAGS_DRV_MODE)
		return opts.attach_mode == XDP_ATTACHED_DRV;
	else if (mode == XDP_FLAGS_SKB_MODE)
		return opts.attach_mode == XDP_ATTACHED_SKB;

	return false;
}

/* Lifted from netlink.c in tools/lib/bpf */
static int netlink_recvmsg(int sock, struct msghdr *mhdr, int flags)
{
	int len;

	do {
		len = recvmsg(sock, mhdr, flags);
	} while (len < 0 && (errno == EINTR || errno == EAGAIN));

	if (len < 0)
		return -errno;
	return len;
}

/* Lifted from netlink.c in tools/lib/bpf */
static int alloc_iov(struct iovec *iov, int len)
{
	void *nbuf;

	nbuf = realloc(iov->iov_base, len);
	if (!nbuf)
		return -ENOMEM;

	iov->iov_base = nbuf;
	iov->iov_len = len;
	return 0;
}

/* Original version lifted from netlink.c in tools/lib/bpf */
static int netlink_recv(int sock)
{
	struct iovec iov = {};
	struct msghdr mhdr = {
		.msg_iov = &iov,
		.msg_iovlen = 1,
	};
	bool multipart = true;
	struct nlmsgerr *err;
	struct nlmsghdr *nh;
	int len, ret;

	ret = alloc_iov(&iov, 4096);
	if (ret)
		goto done;

	while (multipart) {
		multipart = false;
		len = netlink_recvmsg(sock, &mhdr, MSG_PEEK | MSG_TRUNC);
		if (len < 0) {
			ret = len;
			goto done;
		}

		if (len > iov.iov_len) {
			ret = alloc_iov(&iov, len);
			if (ret)
				goto done;
		}

		len = netlink_recvmsg(sock, &mhdr, 0);
		if (len < 0) {
			ret = len;
			goto done;
		}

		if (len == 0)
			break;

		for (nh = (struct nlmsghdr *)iov.iov_base; NLMSG_OK(nh, len);
		     nh = NLMSG_NEXT(nh, len)) {
			if (nh->nlmsg_flags & NLM_F_MULTI)
				multipart = true;
			switch (nh->nlmsg_type) {
			case NLMSG_ERROR:
				err = (struct nlmsgerr *)NLMSG_DATA(nh);
				if (!err->error)
					continue;
				ret = err->error;
				goto done;
			case NLMSG_DONE:
				ret = 0;
				goto done;
			default:
				break;
			}
		}
	}
	ret = 0;
done:
	free(iov.iov_base);
	return ret;
}

int xsk_set_mtu(int ifindex, int mtu)
{
	struct nl_mtu_req req;
	struct rtattr *rta;
	int fd, ret;

	fd = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE);
	if (fd < 0)
		return fd;

	memset(&req, 0, sizeof(req));
	req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg));
	req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
	req.nh.nlmsg_type = RTM_NEWLINK;
	req.msg.ifi_family = AF_UNSPEC;
	req.msg.ifi_index = ifindex;
	rta = (struct rtattr *)(((char *)&req) + NLMSG_ALIGN(req.nh.nlmsg_len));
	rta->rta_type = IFLA_MTU;
	rta->rta_len = RTA_LENGTH(sizeof(unsigned int));
	req.nh.nlmsg_len = NLMSG_ALIGN(req.nh.nlmsg_len) + RTA_LENGTH(sizeof(mtu));
	memcpy(RTA_DATA(rta), &mtu, sizeof(mtu));

	ret = send(fd, &req, req.nh.nlmsg_len, 0);
	if (ret < 0) {
		close(fd);
		return errno;
	}

	ret = netlink_recv(fd);
	close(fd);
	return ret;
}

int xsk_attach_xdp_program(struct bpf_program *prog, int ifindex, u32 xdp_flags)
{
	int prog_fd;

	prog_fd = bpf_program__fd(prog);
	return bpf_xdp_attach(ifindex, prog_fd, xdp_flags, NULL);
}

void xsk_detach_xdp_program(int ifindex, u32 xdp_flags)
{
	bpf_xdp_detach(ifindex, xdp_flags, NULL);
}

void xsk_clear_xskmap(struct bpf_map *map)
{
	u32 index = 0;
	int map_fd;

	map_fd = bpf_map__fd(map);
	bpf_map_delete_elem(map_fd, &index);
}

int xsk_update_xskmap(struct bpf_map *map, struct xsk_socket *xsk)
{
	int map_fd, sock_fd;
	u32 index = 0;

	map_fd = bpf_map__fd(map);
	sock_fd = xsk_socket__fd(xsk);

	return bpf_map_update_elem(map_fd, &index, &sock_fd, 0);
}

static struct xsk_ctx *xsk_get_ctx(struct xsk_umem *umem, int ifindex,
				   __u32 queue_id)
{
	struct xsk_ctx *ctx;

	if (list_empty(&umem->ctx_list))
		return NULL;

	list_for_each_entry(ctx, &umem->ctx_list, list) {
		if (ctx->ifindex == ifindex && ctx->queue_id == queue_id) {
			ctx->refcount++;
			return ctx;
		}
	}

	return NULL;
}

static void xsk_put_ctx(struct xsk_ctx *ctx, bool unmap)
{
	struct xsk_umem *umem = ctx->umem;
	struct xdp_mmap_offsets off;
	int err;

	if (--ctx->refcount)
		return;

	if (!unmap)
		goto out_free;

	err = xsk_get_mmap_offsets(umem->fd, &off);
	if (err)
		goto out_free;

	munmap(ctx->fill->ring - off.fr.desc, off.fr.desc + umem->config.fill_size *
	       sizeof(__u64));
	munmap(ctx->comp->ring - off.cr.desc, off.cr.desc + umem->config.comp_size *
	       sizeof(__u64));

out_free:
	list_del(&ctx->list);
	free(ctx);
}

static struct xsk_ctx *xsk_create_ctx(struct xsk_socket *xsk,
				      struct xsk_umem *umem, int ifindex,
				      __u32 queue_id,
				      struct xsk_ring_prod *fill,
				      struct xsk_ring_cons *comp)
{
	struct xsk_ctx *ctx;
	int err;

	ctx = calloc(1, sizeof(*ctx));
	if (!ctx)
		return NULL;

	if (!umem->fill_save) {
		err = xsk_create_umem_rings(umem, xsk->fd, fill, comp);
		if (err) {
			free(ctx);
			return NULL;
		}
	} else if (umem->fill_save != fill || umem->comp_save != comp) {
		/* Copy over rings to new structs. */
		memcpy(fill, umem->fill_save, sizeof(*fill));
		memcpy(comp, umem->comp_save, sizeof(*comp));
	}

	ctx->ifindex = ifindex;
	ctx->refcount = 1;
	ctx->umem = umem;
	ctx->queue_id = queue_id;

	ctx->fill = fill;
	ctx->comp = comp;
	list_add(&ctx->list, &umem->ctx_list);
	return ctx;
}

int xsk_socket__create_shared(struct xsk_socket **xsk_ptr,
			      int ifindex,
			      __u32 queue_id, struct xsk_umem *umem,
			      struct xsk_ring_cons *rx,
			      struct xsk_ring_prod *tx,
			      struct xsk_ring_prod *fill,
			      struct xsk_ring_cons *comp,
			      const struct xsk_socket_config *usr_config)
{
	bool unmap, rx_setup_done = false, tx_setup_done = false;
	void *rx_map = NULL, *tx_map = NULL;
	struct sockaddr_xdp sxdp = {};
	struct xdp_mmap_offsets off;
	struct xsk_socket *xsk;
	struct xsk_ctx *ctx;
	int err;

	if (!umem || !xsk_ptr || !(rx || tx))
		return -EFAULT;

	unmap = umem->fill_save != fill;

	xsk = calloc(1, sizeof(*xsk));
	if (!xsk)
		return -ENOMEM;

	err = xsk_set_xdp_socket_config(&xsk->config, usr_config);
	if (err)
		goto out_xsk_alloc;

	if (umem->refcount++ > 0) {
		xsk->fd = socket(AF_XDP, SOCK_RAW | SOCK_CLOEXEC, 0);
		if (xsk->fd < 0) {
			err = -errno;
			goto out_xsk_alloc;
		}
	} else {
		xsk->fd = umem->fd;
		rx_setup_done = umem->rx_ring_setup_done;
		tx_setup_done = umem->tx_ring_setup_done;
	}

	ctx = xsk_get_ctx(umem, ifindex, queue_id);
	if (!ctx) {
		if (!fill || !comp) {
			err = -EFAULT;
			goto out_socket;
		}

		ctx = xsk_create_ctx(xsk, umem, ifindex, queue_id, fill, comp);
		if (!ctx) {
			err = -ENOMEM;
			goto out_socket;
		}
	}
	xsk->ctx = ctx;

	if (rx && !rx_setup_done) {
		err = setsockopt(xsk->fd, SOL_XDP, XDP_RX_RING,
				 &xsk->config.rx_size,
				 sizeof(xsk->config.rx_size));
		if (err) {
			err = -errno;
			goto out_put_ctx;
		}
		if (xsk->fd == umem->fd)
			umem->rx_ring_setup_done = true;
	}
	if (tx && !tx_setup_done) {
		err = setsockopt(xsk->fd, SOL_XDP, XDP_TX_RING,
				 &xsk->config.tx_size,
				 sizeof(xsk->config.tx_size));
		if (err) {
			err = -errno;
			goto out_put_ctx;
		}
		if (xsk->fd == umem->fd)
			umem->tx_ring_setup_done = true;
	}

	err = xsk_get_mmap_offsets(xsk->fd, &off);
	if (err) {
		err = -errno;
		goto out_put_ctx;
	}

	if (rx) {
		rx_map = mmap(NULL, off.rx.desc +
			      xsk->config.rx_size * sizeof(struct xdp_desc),
			      PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE,
			      xsk->fd, XDP_PGOFF_RX_RING);
		if (rx_map == MAP_FAILED) {
			err = -errno;
			goto out_put_ctx;
		}

		rx->mask = xsk->config.rx_size - 1;
		rx->size = xsk->config.rx_size;
		rx->producer = rx_map + off.rx.producer;
		rx->consumer = rx_map + off.rx.consumer;
		rx->flags = rx_map + off.rx.flags;
		rx->ring = rx_map + off.rx.desc;
		rx->cached_prod = *rx->producer;
		rx->cached_cons = *rx->consumer;
	}
	xsk->rx = rx;

	if (tx) {
		tx_map = mmap(NULL, off.tx.desc +
			      xsk->config.tx_size * sizeof(struct xdp_desc),
			      PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE,
			      xsk->fd, XDP_PGOFF_TX_RING);
		if (tx_map == MAP_FAILED) {
			err = -errno;
			goto out_mmap_rx;
		}

		tx->mask = xsk->config.tx_size - 1;
		tx->size = xsk->config.tx_size;
		tx->producer = tx_map + off.tx.producer;
		tx->consumer = tx_map + off.tx.consumer;
		tx->flags = tx_map + off.tx.flags;
		tx->ring = tx_map + off.tx.desc;
		tx->cached_prod = *tx->producer;
		/* cached_cons is r->size bigger than the real consumer pointer
		 * See xsk_prod_nb_free
		 */
		tx->cached_cons = *tx->consumer + xsk->config.tx_size;
	}
	xsk->tx = tx;

	sxdp.sxdp_family = PF_XDP;
	sxdp.sxdp_ifindex = ctx->ifindex;
	sxdp.sxdp_queue_id = ctx->queue_id;
	if (umem->refcount > 1) {
		sxdp.sxdp_flags |= XDP_SHARED_UMEM;
		sxdp.sxdp_shared_umem_fd = umem->fd;
	} else {
		sxdp.sxdp_flags = xsk->config.bind_flags;
	}

	err = bind(xsk->fd, (struct sockaddr *)&sxdp, sizeof(sxdp));
	if (err) {
		err = -errno;
		goto out_mmap_tx;
	}

	*xsk_ptr = xsk;
	umem->fill_save = NULL;
	umem->comp_save = NULL;
	return 0;

out_mmap_tx:
	if (tx)
		munmap(tx_map, off.tx.desc +
		       xsk->config.tx_size * sizeof(struct xdp_desc));
out_mmap_rx:
	if (rx)
		munmap(rx_map, off.rx.desc +
		       xsk->config.rx_size * sizeof(struct xdp_desc));
out_put_ctx:
	xsk_put_ctx(ctx, unmap);
out_socket:
	if (--umem->refcount)
		close(xsk->fd);
out_xsk_alloc:
	free(xsk);
	return err;
}

int xsk_socket__create(struct xsk_socket **xsk_ptr, int ifindex,
		       __u32 queue_id, struct xsk_umem *umem,
		       struct xsk_ring_cons *rx, struct xsk_ring_prod *tx,
		       const struct xsk_socket_config *usr_config)
{
	if (!umem)
		return -EFAULT;

	return xsk_socket__create_shared(xsk_ptr, ifindex, queue_id, umem,
					 rx, tx, umem->fill_save,
					 umem->comp_save, usr_config);
}

int xsk_umem__delete(struct xsk_umem *umem)
{
	struct xdp_mmap_offsets off;
	int err;

	if (!umem)
		return 0;

	if (umem->refcount)
		return -EBUSY;

	err = xsk_get_mmap_offsets(umem->fd, &off);
	if (!err && umem->fill_save && umem->comp_save) {
		munmap(umem->fill_save->ring - off.fr.desc,
		       off.fr.desc + umem->config.fill_size * sizeof(__u64));
		munmap(umem->comp_save->ring - off.cr.desc,
		       off.cr.desc + umem->config.comp_size * sizeof(__u64));
	}

	close(umem->fd);
	free(umem);

	return 0;
}

void xsk_socket__delete(struct xsk_socket *xsk)
{
	size_t desc_sz = sizeof(struct xdp_desc);
	struct xdp_mmap_offsets off;
	struct xsk_umem *umem;
	struct xsk_ctx *ctx;
	int err;

	if (!xsk)
		return;

	ctx = xsk->ctx;
	umem = ctx->umem;

	xsk_put_ctx(ctx, true);

	err = xsk_get_mmap_offsets(xsk->fd, &off);
	if (!err) {
		if (xsk->rx) {
			munmap(xsk->rx->ring - off.rx.desc,
			       off.rx.desc + xsk->config.rx_size * desc_sz);
		}
		if (xsk->tx) {
			munmap(xsk->tx->ring - off.tx.desc,
			       off.tx.desc + xsk->config.tx_size * desc_sz);
		}
	}

	umem->refcount--;
	/* Do not close an fd that also has an associated umem connected
	 * to it.
	 */
	if (xsk->fd != umem->fd)
		close(xsk->fd);
	free(xsk);
}