1 files changed, 797 insertions, 0 deletions

diff --git a/src/contrib/libbpf/bpf/xsk.c b/src/contrib/libbpf/bpf/xsk.c
new file mode 100644
index 0000000..8e0ffa8
--- /dev/null
+++ b/src/contrib/libbpf/bpf/xsk.c
@@ -0,0 +1,797 @@
+// 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_packet.h>
+#include <linux/if_xdp.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.h"
+#include "libbpf.h"
+#include "libbpf_internal.h"
+#include "xsk.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
+
+struct xsk_umem {
+	struct xsk_ring_prod *fill;
+	struct xsk_ring_cons *comp;
+	char *umem_area;
+	struct xsk_umem_config config;
+	int fd;
+	int refcount;
+};
+
+struct xsk_socket {
+	struct xsk_ring_cons *rx;
+	struct xsk_ring_prod *tx;
+	__u64 outstanding_tx;
+	struct xsk_umem *umem;
+	struct xsk_socket_config config;
+	int fd;
+	int ifindex;
+	int prog_fd;
+	int xsks_map_fd;
+	__u32 queue_id;
+	char ifname[IFNAMSIZ];
+};
+
+struct xsk_nl_info {
+	bool xdp_prog_attached;
+	int ifindex;
+	int fd;
+};
+
+/* Up until and including Linux 5.3 */
+struct xdp_ring_offset_v1 {
+	__u64 producer;
+	__u64 consumer;
+	__u64 desc;
+};
+
+/* Up until and including Linux 5.3 */
+struct xdp_mmap_offsets_v1 {
+	struct xdp_ring_offset_v1 rx;
+	struct xdp_ring_offset_v1 tx;
+	struct xdp_ring_offset_v1 fr;
+	struct xdp_ring_offset_v1 cr;
+};
+
+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->libbpf_flags = 0;
+		cfg->xdp_flags = 0;
+		cfg->bind_flags = 0;
+		return 0;
+	}
+
+	if (usr_cfg->libbpf_flags & ~XSK_LIBBPF_FLAGS__INHIBIT_PROG_LOAD)
+		return -EINVAL;
+
+	cfg->rx_size = usr_cfg->rx_size;
+	cfg->tx_size = usr_cfg->tx_size;
+	cfg->libbpf_flags = usr_cfg->libbpf_flags;
+	cfg->xdp_flags = usr_cfg->xdp_flags;
+	cfg->bind_flags = usr_cfg->bind_flags;
+
+	return 0;
+}
+
+static void xsk_mmap_offsets_v1(struct xdp_mmap_offsets *off)
+{
+	struct xdp_mmap_offsets_v1 off_v1;
+
+	/* getsockopt on a kernel <= 5.3 has no flags fields.
+	 * Copy over the offsets to the correct places in the >=5.4 format
+	 * and put the flags where they would have been on that kernel.
+	 */
+	memcpy(&off_v1, off, sizeof(off_v1));
+
+	off->rx.producer = off_v1.rx.producer;
+	off->rx.consumer = off_v1.rx.consumer;
+	off->rx.desc = off_v1.rx.desc;
+	off->rx.flags = off_v1.rx.consumer + sizeof(__u32);
+
+	off->tx.producer = off_v1.tx.producer;
+	off->tx.consumer = off_v1.tx.consumer;
+	off->tx.desc = off_v1.tx.desc;
+	off->tx.flags = off_v1.tx.consumer + sizeof(__u32);
+
+	off->fr.producer = off_v1.fr.producer;
+	off->fr.consumer = off_v1.fr.consumer;
+	off->fr.desc = off_v1.fr.desc;
+	off->fr.flags = off_v1.fr.consumer + sizeof(__u32);
+
+	off->cr.producer = off_v1.cr.producer;
+	off->cr.consumer = off_v1.cr.consumer;
+	off->cr.desc = off_v1.cr.desc;
+	off->cr.flags = off_v1.cr.consumer + sizeof(__u32);
+}
+
+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;
+
+	if (optlen == sizeof(struct xdp_mmap_offsets_v1)) {
+		xsk_mmap_offsets_v1(off);
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+int xsk_umem__create_v0_0_4(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_mmap_offsets off;
+	struct xdp_umem_reg mr;
+	struct xsk_umem *umem;
+	void *map;
+	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, 0);
+	if (umem->fd < 0) {
+		err = -errno;
+		goto out_umem_alloc;
+	}
+
+	umem->umem_area = umem_area;
+	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 = setsockopt(umem->fd, SOL_XDP, XDP_UMEM_FILL_RING,
+			 &umem->config.fill_size,
+			 sizeof(umem->config.fill_size));
+	if (err) {
+		err = -errno;
+		goto out_socket;
+	}
+	err = setsockopt(umem->fd, SOL_XDP, XDP_UMEM_COMPLETION_RING,
+			 &umem->config.comp_size,
+			 sizeof(umem->config.comp_size));
+	if (err) {
+		err = -errno;
+		goto out_socket;
+	}
+
+	err = xsk_get_mmap_offsets(umem->fd, &off);
+	if (err) {
+		err = -errno;
+		goto out_socket;
+	}
+
+	map = mmap(NULL, off.fr.desc + umem->config.fill_size * sizeof(__u64),
+		   PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, umem->fd,
+		   XDP_UMEM_PGOFF_FILL_RING);
+	if (map == MAP_FAILED) {
+		err = -errno;
+		goto out_socket;
+	}
+
+	umem->fill = fill;
+	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, umem->fd,
+		   XDP_UMEM_PGOFF_COMPLETION_RING);
+	if (map == MAP_FAILED) {
+		err = -errno;
+		goto out_mmap;
+	}
+
+	umem->comp = comp;
+	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;
+
+	*umem_ptr = umem;
+	return 0;
+
+out_mmap:
+	munmap(map, off.fr.desc + umem->config.fill_size * sizeof(__u64));
+out_socket:
+	close(umem->fd);
+out_umem_alloc:
+	free(umem);
+	return err;
+}
+
+struct xsk_umem_config_v1 {
+	__u32 fill_size;
+	__u32 comp_size;
+	__u32 frame_size;
+	__u32 frame_headroom;
+};
+
+int xsk_umem__create_v0_0_2(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 xsk_umem_config config;
+
+	memcpy(&config, usr_config, sizeof(struct xsk_umem_config_v1));
+	config.flags = 0;
+
+	return xsk_umem__create_v0_0_4(umem_ptr, umem_area, size, fill, comp,
+					&config);
+}
+COMPAT_VERSION(xsk_umem__create_v0_0_2, xsk_umem__create, LIBBPF_0.0.2)
+DEFAULT_VERSION(xsk_umem__create_v0_0_4, xsk_umem__create, LIBBPF_0.0.4)
+
+static int xsk_load_xdp_prog(struct xsk_socket *xsk)
+{
+	static const int log_buf_size = 16 * 1024;
+	char log_buf[log_buf_size];
+	int err, prog_fd;
+
+	/* This is the C-program:
+	 * SEC("xdp_sock") int xdp_sock_prog(struct xdp_md *ctx)
+	 * {
+	 *     int ret, index = ctx->rx_queue_index;
+	 *
+	 *     // A set entry here means that the correspnding queue_id
+	 *     // has an active AF_XDP socket bound to it.
+	 *     ret = bpf_redirect_map(&xsks_map, index, XDP_PASS);
+	 *     if (ret > 0)
+	 *         return ret;
+	 *
+	 *     // Fallback for pre-5.3 kernels, not supporting default
+	 *     // action in the flags parameter.
+	 *     if (bpf_map_lookup_elem(&xsks_map, &index))
+	 *         return bpf_redirect_map(&xsks_map, index, 0);
+	 *     return XDP_PASS;
+	 * }
+	 */
+	struct bpf_insn prog[] = {
+		/* r2 = *(u32 *)(r1 + 16) */
+		BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, 16),
+		/* *(u32 *)(r10 - 4) = r2 */
+		BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_2, -4),
+		/* r1 = xskmap[] */
+		BPF_LD_MAP_FD(BPF_REG_1, xsk->xsks_map_fd),
+		/* r3 = XDP_PASS */
+		BPF_MOV64_IMM(BPF_REG_3, 2),
+		/* call bpf_redirect_map */
+		BPF_EMIT_CALL(BPF_FUNC_redirect_map),
+		/* if w0 != 0 goto pc+13 */
+		BPF_JMP32_IMM(BPF_JSGT, BPF_REG_0, 0, 13),
+		/* r2 = r10 */
+		BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+		/* r2 += -4 */
+		BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -4),
+		/* r1 = xskmap[] */
+		BPF_LD_MAP_FD(BPF_REG_1, xsk->xsks_map_fd),
+		/* call bpf_map_lookup_elem */
+		BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
+		/* r1 = r0 */
+		BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),
+		/* r0 = XDP_PASS */
+		BPF_MOV64_IMM(BPF_REG_0, 2),
+		/* if r1 == 0 goto pc+5 */
+		BPF_JMP_IMM(BPF_JEQ, BPF_REG_1, 0, 5),
+		/* r2 = *(u32 *)(r10 - 4) */
+		BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_10, -4),
+		/* r1 = xskmap[] */
+		BPF_LD_MAP_FD(BPF_REG_1, xsk->xsks_map_fd),
+		/* r3 = 0 */
+		BPF_MOV64_IMM(BPF_REG_3, 0),
+		/* call bpf_redirect_map */
+		BPF_EMIT_CALL(BPF_FUNC_redirect_map),
+		/* The jumps are to this instruction */
+		BPF_EXIT_INSN(),
+	};
+	size_t insns_cnt = sizeof(prog) / sizeof(struct bpf_insn);
+
+	prog_fd = bpf_load_program(BPF_PROG_TYPE_XDP, prog, insns_cnt,
+				   "LGPL-2.1 or BSD-2-Clause", 0, log_buf,
+				   log_buf_size);
+	if (prog_fd < 0) {
+		pr_warn("BPF log buffer:\n%s", log_buf);
+		return prog_fd;
+	}
+
+	err = bpf_set_link_xdp_fd(xsk->ifindex, prog_fd, xsk->config.xdp_flags);
+	if (err) {
+		close(prog_fd);
+		return err;
+	}
+
+	xsk->prog_fd = prog_fd;
+	return 0;
+}
+
+static int xsk_get_max_queues(struct xsk_socket *xsk)
+{
+	struct ethtool_channels channels = { .cmd = ETHTOOL_GCHANNELS };
+	struct ifreq ifr = {};
+	int fd, err, ret;
+
+	fd = socket(AF_INET, SOCK_DGRAM, 0);
+	if (fd < 0)
+		return -errno;
+
+	ifr.ifr_data = (void *)&channels;
+	memcpy(ifr.ifr_name, xsk->ifname, IFNAMSIZ - 1);
+	ifr.ifr_name[IFNAMSIZ - 1] = '\0';
+	err = ioctl(fd, SIOCETHTOOL, &ifr);
+	if (err && errno != EOPNOTSUPP) {
+		ret = -errno;
+		goto out;
+	}
+
+	if (err) {
+		/* If the device says it has no channels, then all traffic
+		 * is sent to a single stream, so max queues = 1.
+		 */
+		ret = 1;
+	} else {
+		/* Take the max of rx, tx, combined. Drivers return
+		 * the number of channels in different ways.
+		 */
+		ret = max(channels.max_rx, channels.max_tx);
+		ret = max(ret, (int)channels.max_combined);
+	}
+
+out:
+	close(fd);
+	return ret;
+}
+
+static int xsk_create_bpf_maps(struct xsk_socket *xsk)
+{
+	int max_queues;
+	int fd;
+
+	max_queues = xsk_get_max_queues(xsk);
+	if (max_queues < 0)
+		return max_queues;
+
+	fd = bpf_create_map_name(BPF_MAP_TYPE_XSKMAP, "xsks_map",
+				 sizeof(int), sizeof(int), max_queues, 0);
+	if (fd < 0)
+		return fd;
+
+	xsk->xsks_map_fd = fd;
+
+	return 0;
+}
+
+static void xsk_delete_bpf_maps(struct xsk_socket *xsk)
+{
+	bpf_map_delete_elem(xsk->xsks_map_fd, &xsk->queue_id);
+	close(xsk->xsks_map_fd);
+}
+
+static int xsk_lookup_bpf_maps(struct xsk_socket *xsk)
+{
+	__u32 i, *map_ids, num_maps, prog_len = sizeof(struct bpf_prog_info);
+	__u32 map_len = sizeof(struct bpf_map_info);
+	struct bpf_prog_info prog_info = {};
+	struct bpf_map_info map_info;
+	int fd, err;
+
+	err = bpf_obj_get_info_by_fd(xsk->prog_fd, &prog_info, &prog_len);
+	if (err)
+		return err;
+
+	num_maps = prog_info.nr_map_ids;
+
+	map_ids = calloc(prog_info.nr_map_ids, sizeof(*map_ids));
+	if (!map_ids)
+		return -ENOMEM;
+
+	memset(&prog_info, 0, prog_len);
+	prog_info.nr_map_ids = num_maps;
+	prog_info.map_ids = (__u64)(unsigned long)map_ids;
+
+	err = bpf_obj_get_info_by_fd(xsk->prog_fd, &prog_info, &prog_len);
+	if (err)
+		goto out_map_ids;
+
+	xsk->xsks_map_fd = -1;
+
+	for (i = 0; i < prog_info.nr_map_ids; i++) {
+		fd = bpf_map_get_fd_by_id(map_ids[i]);
+		if (fd < 0)
+			continue;
+
+		err = bpf_obj_get_info_by_fd(fd, &map_info, &map_len);
+		if (err) {
+			close(fd);
+			continue;
+		}
+
+		if (!strcmp(map_info.name, "xsks_map")) {
+			xsk->xsks_map_fd = fd;
+			continue;
+		}
+
+		close(fd);
+	}
+
+	err = 0;
+	if (xsk->xsks_map_fd == -1)
+		err = -ENOENT;
+
+out_map_ids:
+	free(map_ids);
+	return err;
+}
+
+static int xsk_set_bpf_maps(struct xsk_socket *xsk)
+{
+	return bpf_map_update_elem(xsk->xsks_map_fd, &xsk->queue_id,
+				   &xsk->fd, 0);
+}
+
+static int xsk_setup_xdp_prog(struct xsk_socket *xsk)
+{
+	__u32 prog_id = 0;
+	int err;
+
+	err = bpf_get_link_xdp_id(xsk->ifindex, &prog_id,
+				  xsk->config.xdp_flags);
+	if (err)
+		return err;
+
+	if (!prog_id) {
+		err = xsk_create_bpf_maps(xsk);
+		if (err)
+			return err;
+
+		err = xsk_load_xdp_prog(xsk);
+		if (err) {
+			xsk_delete_bpf_maps(xsk);
+			return err;
+		}
+	} else {
+		xsk->prog_fd = bpf_prog_get_fd_by_id(prog_id);
+		if (xsk->prog_fd < 0)
+			return -errno;
+		err = xsk_lookup_bpf_maps(xsk);
+		if (err) {
+			close(xsk->prog_fd);
+			return err;
+		}
+	}
+
+	if (xsk->rx)
+		err = xsk_set_bpf_maps(xsk);
+	if (err) {
+		xsk_delete_bpf_maps(xsk);
+		close(xsk->prog_fd);
+		return err;
+	}
+
+	return 0;
+}
+
+int xsk_socket__create(struct xsk_socket **xsk_ptr, const char *ifname,
+		       __u32 queue_id, struct xsk_umem *umem,
+		       struct xsk_ring_cons *rx, struct xsk_ring_prod *tx,
+		       const struct xsk_socket_config *usr_config)
+{
+	void *rx_map = NULL, *tx_map = NULL;
+	struct sockaddr_xdp sxdp = {};
+	struct xdp_mmap_offsets off;
+	struct xsk_socket *xsk;
+	int err;
+
+	if (!umem || !xsk_ptr || !(rx || tx))
+		return -EFAULT;
+
+	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 &&
+	    !(xsk->config.libbpf_flags & XSK_LIBBPF_FLAGS__INHIBIT_PROG_LOAD)) {
+		pr_warn("Error: shared umems not supported by libbpf supplied XDP program.\n");
+		err = -EBUSY;
+		goto out_xsk_alloc;
+	}
+
+	if (umem->refcount++ > 0) {
+		xsk->fd = socket(AF_XDP, SOCK_RAW, 0);
+		if (xsk->fd < 0) {
+			err = -errno;
+			goto out_xsk_alloc;
+		}
+	} else {
+		xsk->fd = umem->fd;
+	}
+
+	xsk->outstanding_tx = 0;
+	xsk->queue_id = queue_id;
+	xsk->umem = umem;
+	xsk->ifindex = if_nametoindex(ifname);
+	if (!xsk->ifindex) {
+		err = -errno;
+		goto out_socket;
+	}
+	memcpy(xsk->ifname, ifname, IFNAMSIZ - 1);
+	xsk->ifname[IFNAMSIZ - 1] = '\0';
+
+	if (rx) {
+		err = setsockopt(xsk->fd, SOL_XDP, XDP_RX_RING,
+				 &xsk->config.rx_size,
+				 sizeof(xsk->config.rx_size));
+		if (err) {
+			err = -errno;
+			goto out_socket;
+		}
+	}
+	if (tx) {
+		err = setsockopt(xsk->fd, SOL_XDP, XDP_TX_RING,
+				 &xsk->config.tx_size,
+				 sizeof(xsk->config.tx_size));
+		if (err) {
+			err = -errno;
+			goto out_socket;
+		}
+	}
+
+	err = xsk_get_mmap_offsets(xsk->fd, &off);
+	if (err) {
+		err = -errno;
+		goto out_socket;
+	}
+
+	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_socket;
+		}
+
+		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;
+	}
+	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_cons = xsk->config.tx_size;
+	}
+	xsk->tx = tx;
+
+	sxdp.sxdp_family = PF_XDP;
+	sxdp.sxdp_ifindex = xsk->ifindex;
+	sxdp.sxdp_queue_id = xsk->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->prog_fd = -1;
+
+	if (!(xsk->config.libbpf_flags & XSK_LIBBPF_FLAGS__INHIBIT_PROG_LOAD)) {
+		err = xsk_setup_xdp_prog(xsk);
+		if (err)
+			goto out_mmap_tx;
+	}
+
+	*xsk_ptr = xsk;
+	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_socket:
+	if (--umem->refcount)
+		close(xsk->fd);
+out_xsk_alloc:
+	free(xsk);
+	return err;
+}
+
+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) {
+		munmap(umem->fill->ring - off.fr.desc,
+		       off.fr.desc + umem->config.fill_size * sizeof(__u64));
+		munmap(umem->comp->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;
+	int err;
+
+	if (!xsk)
+		return;
+
+	if (xsk->prog_fd != -1) {
+		xsk_delete_bpf_maps(xsk);
+		close(xsk->prog_fd);
+	}
+
+	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);
+		}
+
+	}
+
+	xsk->umem->refcount--;
+	/* Do not close an fd that also has an associated umem connected
+	 * to it.
+	 */
+	if (xsk->fd != xsk->umem->fd)
+		close(xsk->fd);
+	free(xsk);
+}