libbpf: move xsk.{c,h} into selftests/bpf
authorAndrii Nakryiko <andrii@kernel.org>
Mon, 27 Jun 2022 21:15:13 +0000 (14:15 -0700)
committerAlexei Starovoitov <ast@kernel.org>
Tue, 28 Jun 2022 20:13:32 +0000 (13:13 -0700)
Remove deprecated xsk APIs from libbpf. But given we have selftests
relying on this, move those files (with minimal adjustments to make them
compilable) under selftests/bpf.

We also remove all the removed APIs from libbpf.map, while overall
keeping version inheritance chain, as most APIs are backwards
compatible so there is no need to reassign them as LIBBPF_1.0.0 versions.

Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220627211527.2245459-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
tools/lib/bpf/Build
tools/lib/bpf/Makefile
tools/lib/bpf/libbpf.map
tools/lib/bpf/xsk.c [deleted file]
tools/lib/bpf/xsk.h [deleted file]
tools/testing/selftests/bpf/Makefile
tools/testing/selftests/bpf/xdpxceiver.c
tools/testing/selftests/bpf/xsk.c [new file with mode: 0644]
tools/testing/selftests/bpf/xsk.h [new file with mode: 0644]

index 31a1a90159023d07574c483c18b2be07946ca118..5a3dfb56d78fdb1ee028013987087de3c20f3894 100644 (file)
@@ -1,4 +1,4 @@
 libbpf-y := libbpf.o bpf.o nlattr.o btf.o libbpf_errno.o str_error.o \
-           netlink.o bpf_prog_linfo.o libbpf_probes.o xsk.o hashmap.o \
+           netlink.o bpf_prog_linfo.o libbpf_probes.o hashmap.o \
            btf_dump.o ringbuf.o strset.o linker.o gen_loader.o relo_core.o \
            usdt.o
index a1265b15202702b561d7212598ed2e192e30aeec..4c904ef0b47e9e6807ea71df547d91c75e5aca1e 100644 (file)
@@ -237,7 +237,7 @@ install_lib: all_cmd
                $(call do_install_mkdir,$(libdir_SQ)); \
                cp -fpR $(LIB_FILE) $(DESTDIR)$(libdir_SQ)
 
-SRC_HDRS := bpf.h libbpf.h btf.h libbpf_common.h libbpf_legacy.h xsk.h      \
+SRC_HDRS := bpf.h libbpf.h btf.h libbpf_common.h libbpf_legacy.h            \
            bpf_helpers.h bpf_tracing.h bpf_endian.h bpf_core_read.h         \
            skel_internal.h libbpf_version.h usdt.bpf.h
 GEN_HDRS := $(BPF_GENERATED)
index 116a2a8ee7c218eb6446cefe63819972b8ba8b2b..da7a4f92845296c8b443f8d2d4a5bee0af0a9f92 100644 (file)
@@ -147,12 +147,6 @@ LIBBPF_0.0.2 {
                btf_ext__new;
                btf_ext__reloc_func_info;
                btf_ext__reloc_line_info;
-               xsk_umem__create;
-               xsk_socket__create;
-               xsk_umem__delete;
-               xsk_socket__delete;
-               xsk_umem__fd;
-               xsk_socket__fd;
                bpf_program__get_prog_info_linear;
                bpf_program__bpil_addr_to_offs;
                bpf_program__bpil_offs_to_addr;
@@ -183,7 +177,6 @@ LIBBPF_0.0.4 {
                perf_buffer__new;
                perf_buffer__new_raw;
                perf_buffer__poll;
-               xsk_umem__create;
 } LIBBPF_0.0.3;
 
 LIBBPF_0.0.5 {
@@ -336,7 +329,6 @@ LIBBPF_0.2.0 {
                perf_buffer__buffer_fd;
                perf_buffer__epoll_fd;
                perf_buffer__consume_buffer;
-               xsk_socket__create_shared;
 } LIBBPF_0.1.0;
 
 LIBBPF_0.3.0 {
@@ -348,8 +340,6 @@ LIBBPF_0.3.0 {
                btf__new_empty_split;
                btf__new_split;
                ring_buffer__epoll_fd;
-               xsk_setup_xdp_prog;
-               xsk_socket__update_xskmap;
 } LIBBPF_0.2.0;
 
 LIBBPF_0.4.0 {
@@ -468,6 +458,4 @@ LIBBPF_1.0.0 {
                libbpf_bpf_link_type_str;
                libbpf_bpf_map_type_str;
                libbpf_bpf_prog_type_str;
-
-       local: *;
 };
diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c
deleted file mode 100644 (file)
index af136f7..0000000
+++ /dev/null
@@ -1,1260 +0,0 @@
-// 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/kernel.h>
-#include <linux/list.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 <linux/if_link.h>
-
-#include "bpf.h"
-#include "libbpf.h"
-#include "libbpf_internal.h"
-#include "xsk.h"
-
-/* entire xsk.h and xsk.c is going away in libbpf 1.0, so ignore all internal
- * uses of deprecated APIs
- */
-#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
-
-#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
-
-enum xsk_prog {
-       XSK_PROG_FALLBACK,
-       XSK_PROG_REDIRECT_FLAGS,
-};
-
-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;
-       int prog_fd;
-       int link_fd;
-       int xsks_map_fd;
-       char ifname[IFNAMSIZ];
-       bool has_bpf_link;
-};
-
-struct xsk_socket {
-       struct xsk_ring_cons *rx;
-       struct xsk_ring_prod *tx;
-       __u64 outstanding_tx;
-       struct xsk_ctx *ctx;
-       struct xsk_socket_config config;
-       int fd;
-};
-
-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;
-}
-
-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;
-}
-
-DEFAULT_VERSION(xsk_umem__create_v0_0_4, xsk_umem__create, LIBBPF_0.0.4)
-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_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;
-}
-
-struct xsk_umem_config_v1 {
-       __u32 fill_size;
-       __u32 comp_size;
-       __u32 frame_size;
-       __u32 frame_headroom;
-};
-
-COMPAT_VERSION(xsk_umem__create_v0_0_2, xsk_umem__create, LIBBPF_0.0.2)
-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);
-}
-
-static enum xsk_prog get_xsk_prog(void)
-{
-       enum xsk_prog detected = XSK_PROG_FALLBACK;
-       __u32 size_out, retval, duration;
-       char data_in = 0, data_out;
-       struct bpf_insn insns[] = {
-               BPF_LD_MAP_FD(BPF_REG_1, 0),
-               BPF_MOV64_IMM(BPF_REG_2, 0),
-               BPF_MOV64_IMM(BPF_REG_3, XDP_PASS),
-               BPF_EMIT_CALL(BPF_FUNC_redirect_map),
-               BPF_EXIT_INSN(),
-       };
-       int prog_fd, map_fd, ret, insn_cnt = ARRAY_SIZE(insns);
-
-       map_fd = bpf_map_create(BPF_MAP_TYPE_XSKMAP, NULL, sizeof(int), sizeof(int), 1, NULL);
-       if (map_fd < 0)
-               return detected;
-
-       insns[0].imm = map_fd;
-
-       prog_fd = bpf_prog_load(BPF_PROG_TYPE_XDP, NULL, "GPL", insns, insn_cnt, NULL);
-       if (prog_fd < 0) {
-               close(map_fd);
-               return detected;
-       }
-
-       ret = bpf_prog_test_run(prog_fd, 0, &data_in, 1, &data_out, &size_out, &retval, &duration);
-       if (!ret && retval == XDP_PASS)
-               detected = XSK_PROG_REDIRECT_FLAGS;
-       close(prog_fd);
-       close(map_fd);
-       return detected;
-}
-
-static int xsk_load_xdp_prog(struct xsk_socket *xsk)
-{
-       static const int log_buf_size = 16 * 1024;
-       struct xsk_ctx *ctx = xsk->ctx;
-       char log_buf[log_buf_size];
-       int prog_fd;
-
-       /* This is the fallback 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, ctx->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, ctx->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, ctx->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(),
-       };
-
-       /* This is the post-5.3 kernel C-program:
-        * SEC("xdp_sock") int xdp_sock_prog(struct xdp_md *ctx)
-        * {
-        *     return bpf_redirect_map(&xsks_map, ctx->rx_queue_index, XDP_PASS);
-        * }
-        */
-       struct bpf_insn prog_redirect_flags[] = {
-               /* r2 = *(u32 *)(r1 + 16) */
-               BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, 16),
-               /* r1 = xskmap[] */
-               BPF_LD_MAP_FD(BPF_REG_1, ctx->xsks_map_fd),
-               /* r3 = XDP_PASS */
-               BPF_MOV64_IMM(BPF_REG_3, 2),
-               /* call bpf_redirect_map */
-               BPF_EMIT_CALL(BPF_FUNC_redirect_map),
-               BPF_EXIT_INSN(),
-       };
-       size_t insns_cnt[] = {ARRAY_SIZE(prog),
-                             ARRAY_SIZE(prog_redirect_flags),
-       };
-       struct bpf_insn *progs[] = {prog, prog_redirect_flags};
-       enum xsk_prog option = get_xsk_prog();
-       LIBBPF_OPTS(bpf_prog_load_opts, opts,
-               .log_buf = log_buf,
-               .log_size = log_buf_size,
-       );
-
-       prog_fd = bpf_prog_load(BPF_PROG_TYPE_XDP, NULL, "LGPL-2.1 or BSD-2-Clause",
-                               progs[option], insns_cnt[option], &opts);
-       if (prog_fd < 0) {
-               pr_warn("BPF log buffer:\n%s", log_buf);
-               return prog_fd;
-       }
-
-       ctx->prog_fd = prog_fd;
-       return 0;
-}
-
-static int xsk_create_bpf_link(struct xsk_socket *xsk)
-{
-       DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts);
-       struct xsk_ctx *ctx = xsk->ctx;
-       __u32 prog_id = 0;
-       int link_fd;
-       int err;
-
-       err = bpf_get_link_xdp_id(ctx->ifindex, &prog_id, xsk->config.xdp_flags);
-       if (err) {
-               pr_warn("getting XDP prog id failed\n");
-               return err;
-       }
-
-       /* if there's a netlink-based XDP prog loaded on interface, bail out
-        * and ask user to do the removal by himself
-        */
-       if (prog_id) {
-               pr_warn("Netlink-based XDP prog detected, please unload it in order to launch AF_XDP prog\n");
-               return -EINVAL;
-       }
-
-       opts.flags = xsk->config.xdp_flags & ~(XDP_FLAGS_UPDATE_IF_NOEXIST | XDP_FLAGS_REPLACE);
-
-       link_fd = bpf_link_create(ctx->prog_fd, ctx->ifindex, BPF_XDP, &opts);
-       if (link_fd < 0) {
-               pr_warn("bpf_link_create failed: %s\n", strerror(errno));
-               return link_fd;
-       }
-
-       ctx->link_fd = link_fd;
-       return 0;
-}
-
-static int xsk_get_max_queues(struct xsk_socket *xsk)
-{
-       struct ethtool_channels channels = { .cmd = ETHTOOL_GCHANNELS };
-       struct xsk_ctx *ctx = xsk->ctx;
-       struct ifreq ifr = {};
-       int fd, err, ret;
-
-       fd = socket(AF_LOCAL, SOCK_DGRAM | SOCK_CLOEXEC, 0);
-       if (fd < 0)
-               return -errno;
-
-       ifr.ifr_data = (void *)&channels;
-       libbpf_strlcpy(ifr.ifr_name, ctx->ifname, IFNAMSIZ);
-       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)
-{
-       struct xsk_ctx *ctx = xsk->ctx;
-       int max_queues;
-       int fd;
-
-       max_queues = xsk_get_max_queues(xsk);
-       if (max_queues < 0)
-               return max_queues;
-
-       fd = bpf_map_create(BPF_MAP_TYPE_XSKMAP, "xsks_map",
-                           sizeof(int), sizeof(int), max_queues, NULL);
-       if (fd < 0)
-               return fd;
-
-       ctx->xsks_map_fd = fd;
-
-       return 0;
-}
-
-static void xsk_delete_bpf_maps(struct xsk_socket *xsk)
-{
-       struct xsk_ctx *ctx = xsk->ctx;
-
-       bpf_map_delete_elem(ctx->xsks_map_fd, &ctx->queue_id);
-       close(ctx->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 xsk_ctx *ctx = xsk->ctx;
-       struct bpf_map_info map_info;
-       int fd, err;
-
-       err = bpf_obj_get_info_by_fd(ctx->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(ctx->prog_fd, &prog_info, &prog_len);
-       if (err)
-               goto out_map_ids;
-
-       ctx->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;
-
-               memset(&map_info, 0, map_len);
-               err = bpf_obj_get_info_by_fd(fd, &map_info, &map_len);
-               if (err) {
-                       close(fd);
-                       continue;
-               }
-
-               if (!strncmp(map_info.name, "xsks_map", sizeof(map_info.name))) {
-                       ctx->xsks_map_fd = fd;
-                       break;
-               }
-
-               close(fd);
-       }
-
-       if (ctx->xsks_map_fd == -1)
-               err = -ENOENT;
-
-out_map_ids:
-       free(map_ids);
-       return err;
-}
-
-static int xsk_set_bpf_maps(struct xsk_socket *xsk)
-{
-       struct xsk_ctx *ctx = xsk->ctx;
-
-       return bpf_map_update_elem(ctx->xsks_map_fd, &ctx->queue_id,
-                                  &xsk->fd, 0);
-}
-
-static int xsk_link_lookup(int ifindex, __u32 *prog_id, int *link_fd)
-{
-       struct bpf_link_info link_info;
-       __u32 link_len;
-       __u32 id = 0;
-       int err;
-       int fd;
-
-       while (true) {
-               err = bpf_link_get_next_id(id, &id);
-               if (err) {
-                       if (errno == ENOENT) {
-                               err = 0;
-                               break;
-                       }
-                       pr_warn("can't get next link: %s\n", strerror(errno));
-                       break;
-               }
-
-               fd = bpf_link_get_fd_by_id(id);
-               if (fd < 0) {
-                       if (errno == ENOENT)
-                               continue;
-                       pr_warn("can't get link by id (%u): %s\n", id, strerror(errno));
-                       err = -errno;
-                       break;
-               }
-
-               link_len = sizeof(struct bpf_link_info);
-               memset(&link_info, 0, link_len);
-               err = bpf_obj_get_info_by_fd(fd, &link_info, &link_len);
-               if (err) {
-                       pr_warn("can't get link info: %s\n", strerror(errno));
-                       close(fd);
-                       break;
-               }
-               if (link_info.type == BPF_LINK_TYPE_XDP) {
-                       if (link_info.xdp.ifindex == ifindex) {
-                               *link_fd = fd;
-                               if (prog_id)
-                                       *prog_id = link_info.prog_id;
-                               break;
-                       }
-               }
-               close(fd);
-       }
-
-       return err;
-}
-
-static bool xsk_probe_bpf_link(void)
-{
-       LIBBPF_OPTS(bpf_link_create_opts, opts, .flags = XDP_FLAGS_SKB_MODE);
-       struct bpf_insn insns[2] = {
-               BPF_MOV64_IMM(BPF_REG_0, XDP_PASS),
-               BPF_EXIT_INSN()
-       };
-       int prog_fd, link_fd = -1, insn_cnt = ARRAY_SIZE(insns);
-       int ifindex_lo = 1;
-       bool ret = false;
-       int err;
-
-       err = xsk_link_lookup(ifindex_lo, NULL, &link_fd);
-       if (err)
-               return ret;
-
-       if (link_fd >= 0)
-               return true;
-
-       prog_fd = bpf_prog_load(BPF_PROG_TYPE_XDP, NULL, "GPL", insns, insn_cnt, NULL);
-       if (prog_fd < 0)
-               return ret;
-
-       link_fd = bpf_link_create(prog_fd, ifindex_lo, BPF_XDP, &opts);
-       close(prog_fd);
-
-       if (link_fd >= 0) {
-               ret = true;
-               close(link_fd);
-       }
-
-       return ret;
-}
-
-static int xsk_create_xsk_struct(int ifindex, struct xsk_socket *xsk)
-{
-       char ifname[IFNAMSIZ];
-       struct xsk_ctx *ctx;
-       char *interface;
-
-       ctx = calloc(1, sizeof(*ctx));
-       if (!ctx)
-               return -ENOMEM;
-
-       interface = if_indextoname(ifindex, &ifname[0]);
-       if (!interface) {
-               free(ctx);
-               return -errno;
-       }
-
-       ctx->ifindex = ifindex;
-       libbpf_strlcpy(ctx->ifname, ifname, IFNAMSIZ);
-
-       xsk->ctx = ctx;
-       xsk->ctx->has_bpf_link = xsk_probe_bpf_link();
-
-       return 0;
-}
-
-static int xsk_init_xdp_res(struct xsk_socket *xsk,
-                           int *xsks_map_fd)
-{
-       struct xsk_ctx *ctx = xsk->ctx;
-       int err;
-
-       err = xsk_create_bpf_maps(xsk);
-       if (err)
-               return err;
-
-       err = xsk_load_xdp_prog(xsk);
-       if (err)
-               goto err_load_xdp_prog;
-
-       if (ctx->has_bpf_link)
-               err = xsk_create_bpf_link(xsk);
-       else
-               err = bpf_set_link_xdp_fd(xsk->ctx->ifindex, ctx->prog_fd,
-                                         xsk->config.xdp_flags);
-
-       if (err)
-               goto err_attach_xdp_prog;
-
-       if (!xsk->rx)
-               return err;
-
-       err = xsk_set_bpf_maps(xsk);
-       if (err)
-               goto err_set_bpf_maps;
-
-       return err;
-
-err_set_bpf_maps:
-       if (ctx->has_bpf_link)
-               close(ctx->link_fd);
-       else
-               bpf_set_link_xdp_fd(ctx->ifindex, -1, 0);
-err_attach_xdp_prog:
-       close(ctx->prog_fd);
-err_load_xdp_prog:
-       xsk_delete_bpf_maps(xsk);
-       return err;
-}
-
-static int xsk_lookup_xdp_res(struct xsk_socket *xsk, int *xsks_map_fd, int prog_id)
-{
-       struct xsk_ctx *ctx = xsk->ctx;
-       int err;
-
-       ctx->prog_fd = bpf_prog_get_fd_by_id(prog_id);
-       if (ctx->prog_fd < 0) {
-               err = -errno;
-               goto err_prog_fd;
-       }
-       err = xsk_lookup_bpf_maps(xsk);
-       if (err)
-               goto err_lookup_maps;
-
-       if (!xsk->rx)
-               return err;
-
-       err = xsk_set_bpf_maps(xsk);
-       if (err)
-               goto err_set_maps;
-
-       return err;
-
-err_set_maps:
-       close(ctx->xsks_map_fd);
-err_lookup_maps:
-       close(ctx->prog_fd);
-err_prog_fd:
-       if (ctx->has_bpf_link)
-               close(ctx->link_fd);
-       return err;
-}
-
-static int __xsk_setup_xdp_prog(struct xsk_socket *_xdp, int *xsks_map_fd)
-{
-       struct xsk_socket *xsk = _xdp;
-       struct xsk_ctx *ctx = xsk->ctx;
-       __u32 prog_id = 0;
-       int err;
-
-       if (ctx->has_bpf_link)
-               err = xsk_link_lookup(ctx->ifindex, &prog_id, &ctx->link_fd);
-       else
-               err = bpf_get_link_xdp_id(ctx->ifindex, &prog_id, xsk->config.xdp_flags);
-
-       if (err)
-               return err;
-
-       err = !prog_id ? xsk_init_xdp_res(xsk, xsks_map_fd) :
-                        xsk_lookup_xdp_res(xsk, xsks_map_fd, prog_id);
-
-       if (!err && xsks_map_fd)
-               *xsks_map_fd = ctx->xsks_map_fd;
-
-       return err;
-}
-
-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,
-                                     const char *ifname, __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;
-       libbpf_strlcpy(ctx->ifname, ifname, IFNAMSIZ);
-
-       ctx->fill = fill;
-       ctx->comp = comp;
-       list_add(&ctx->list, &umem->ctx_list);
-       return ctx;
-}
-
-static void xsk_destroy_xsk_struct(struct xsk_socket *xsk)
-{
-       free(xsk->ctx);
-       free(xsk);
-}
-
-int xsk_socket__update_xskmap(struct xsk_socket *xsk, int fd)
-{
-       xsk->ctx->xsks_map_fd = fd;
-       return xsk_set_bpf_maps(xsk);
-}
-
-int xsk_setup_xdp_prog(int ifindex, int *xsks_map_fd)
-{
-       struct xsk_socket *xsk;
-       int res;
-
-       xsk = calloc(1, sizeof(*xsk));
-       if (!xsk)
-               return -ENOMEM;
-
-       res = xsk_create_xsk_struct(ifindex, xsk);
-       if (res) {
-               free(xsk);
-               return -EINVAL;
-       }
-
-       res = __xsk_setup_xdp_prog(xsk, xsks_map_fd);
-
-       xsk_destroy_xsk_struct(xsk);
-
-       return res;
-}
-
-int xsk_socket__create_shared(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,
-                             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, ifindex;
-
-       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;
-
-       xsk->outstanding_tx = 0;
-       ifindex = if_nametoindex(ifname);
-       if (!ifindex) {
-               err = -errno;
-               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, ifname, queue_id,
-                                    fill, comp);
-               if (!ctx) {
-                       err = -ENOMEM;
-                       goto out_socket;
-               }
-       }
-       xsk->ctx = ctx;
-       xsk->ctx->has_bpf_link = xsk_probe_bpf_link();
-
-       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;
-       }
-
-       ctx->prog_fd = -1;
-
-       if (!(xsk->config.libbpf_flags & XSK_LIBBPF_FLAGS__INHIBIT_PROG_LOAD)) {
-               err = __xsk_setup_xdp_prog(xsk, NULL);
-               if (err)
-                       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, 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)
-{
-       if (!umem)
-               return -EFAULT;
-
-       return xsk_socket__create_shared(xsk_ptr, ifname, 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;
-       if (ctx->prog_fd != -1) {
-               xsk_delete_bpf_maps(xsk);
-               close(ctx->prog_fd);
-               if (ctx->has_bpf_link)
-                       close(ctx->link_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_put_ctx(ctx, true);
-
-       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);
-}
diff --git a/tools/lib/bpf/xsk.h b/tools/lib/bpf/xsk.h
deleted file mode 100644 (file)
index 64e9c57..0000000
+++ /dev/null
@@ -1,336 +0,0 @@
-/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
-
-/*
- * AF_XDP user-space access library.
- *
- * Copyright (c) 2018 - 2019 Intel Corporation.
- * Copyright (c) 2019 Facebook
- *
- * Author(s): Magnus Karlsson <magnus.karlsson@intel.com>
- */
-
-#ifndef __LIBBPF_XSK_H
-#define __LIBBPF_XSK_H
-
-#include <stdio.h>
-#include <stdint.h>
-#include <stdbool.h>
-#include <linux/if_xdp.h>
-
-#include "libbpf.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/* This whole API has been deprecated and moved to libxdp that can be found at
- * https://github.com/xdp-project/xdp-tools. The APIs are exactly the same so
- * it should just be linking with libxdp instead of libbpf for this set of
- * functionality. If not, please submit a bug report on the aforementioned page.
- */
-
-/* Load-Acquire Store-Release barriers used by the XDP socket
- * library. The following macros should *NOT* be considered part of
- * the xsk.h API, and is subject to change anytime.
- *
- * LIBRARY INTERNAL
- */
-
-#define __XSK_READ_ONCE(x) (*(volatile typeof(x) *)&x)
-#define __XSK_WRITE_ONCE(x, v) (*(volatile typeof(x) *)&x) = (v)
-
-#if defined(__i386__) || defined(__x86_64__)
-# define libbpf_smp_store_release(p, v)                                        \
-       do {                                                            \
-               asm volatile("" : : : "memory");                        \
-               __XSK_WRITE_ONCE(*p, v);                                \
-       } while (0)
-# define libbpf_smp_load_acquire(p)                                    \
-       ({                                                              \
-               typeof(*p) ___p1 = __XSK_READ_ONCE(*p);                 \
-               asm volatile("" : : : "memory");                        \
-               ___p1;                                                  \
-       })
-#elif defined(__aarch64__)
-# define libbpf_smp_store_release(p, v)                                        \
-               asm volatile ("stlr %w1, %0" : "=Q" (*p) : "r" (v) : "memory")
-# define libbpf_smp_load_acquire(p)                                    \
-       ({                                                              \
-               typeof(*p) ___p1;                                       \
-               asm volatile ("ldar %w0, %1"                            \
-                             : "=r" (___p1) : "Q" (*p) : "memory");    \
-               ___p1;                                                  \
-       })
-#elif defined(__riscv)
-# define libbpf_smp_store_release(p, v)                                        \
-       do {                                                            \
-               asm volatile ("fence rw,w" : : : "memory");             \
-               __XSK_WRITE_ONCE(*p, v);                                \
-       } while (0)
-# define libbpf_smp_load_acquire(p)                                    \
-       ({                                                              \
-               typeof(*p) ___p1 = __XSK_READ_ONCE(*p);                 \
-               asm volatile ("fence r,rw" : : : "memory");             \
-               ___p1;                                                  \
-       })
-#endif
-
-#ifndef libbpf_smp_store_release
-#define libbpf_smp_store_release(p, v)                                 \
-       do {                                                            \
-               __sync_synchronize();                                   \
-               __XSK_WRITE_ONCE(*p, v);                                \
-       } while (0)
-#endif
-
-#ifndef libbpf_smp_load_acquire
-#define libbpf_smp_load_acquire(p)                                     \
-       ({                                                              \
-               typeof(*p) ___p1 = __XSK_READ_ONCE(*p);                 \
-               __sync_synchronize();                                   \
-               ___p1;                                                  \
-       })
-#endif
-
-/* LIBRARY INTERNAL -- END */
-
-/* Do not access these members directly. Use the functions below. */
-#define DEFINE_XSK_RING(name) \
-struct name { \
-       __u32 cached_prod; \
-       __u32 cached_cons; \
-       __u32 mask; \
-       __u32 size; \
-       __u32 *producer; \
-       __u32 *consumer; \
-       void *ring; \
-       __u32 *flags; \
-}
-
-DEFINE_XSK_RING(xsk_ring_prod);
-DEFINE_XSK_RING(xsk_ring_cons);
-
-/* For a detailed explanation on the memory barriers associated with the
- * ring, please take a look at net/xdp/xsk_queue.h.
- */
-
-struct xsk_umem;
-struct xsk_socket;
-
-static inline __u64 *xsk_ring_prod__fill_addr(struct xsk_ring_prod *fill,
-                                             __u32 idx)
-{
-       __u64 *addrs = (__u64 *)fill->ring;
-
-       return &addrs[idx & fill->mask];
-}
-
-static inline const __u64 *
-xsk_ring_cons__comp_addr(const struct xsk_ring_cons *comp, __u32 idx)
-{
-       const __u64 *addrs = (const __u64 *)comp->ring;
-
-       return &addrs[idx & comp->mask];
-}
-
-static inline struct xdp_desc *xsk_ring_prod__tx_desc(struct xsk_ring_prod *tx,
-                                                     __u32 idx)
-{
-       struct xdp_desc *descs = (struct xdp_desc *)tx->ring;
-
-       return &descs[idx & tx->mask];
-}
-
-static inline const struct xdp_desc *
-xsk_ring_cons__rx_desc(const struct xsk_ring_cons *rx, __u32 idx)
-{
-       const struct xdp_desc *descs = (const struct xdp_desc *)rx->ring;
-
-       return &descs[idx & rx->mask];
-}
-
-static inline int xsk_ring_prod__needs_wakeup(const struct xsk_ring_prod *r)
-{
-       return *r->flags & XDP_RING_NEED_WAKEUP;
-}
-
-static inline __u32 xsk_prod_nb_free(struct xsk_ring_prod *r, __u32 nb)
-{
-       __u32 free_entries = r->cached_cons - r->cached_prod;
-
-       if (free_entries >= nb)
-               return free_entries;
-
-       /* Refresh the local tail pointer.
-        * cached_cons is r->size bigger than the real consumer pointer so
-        * that this addition can be avoided in the more frequently
-        * executed code that computs free_entries in the beginning of
-        * this function. Without this optimization it whould have been
-        * free_entries = r->cached_prod - r->cached_cons + r->size.
-        */
-       r->cached_cons = libbpf_smp_load_acquire(r->consumer);
-       r->cached_cons += r->size;
-
-       return r->cached_cons - r->cached_prod;
-}
-
-static inline __u32 xsk_cons_nb_avail(struct xsk_ring_cons *r, __u32 nb)
-{
-       __u32 entries = r->cached_prod - r->cached_cons;
-
-       if (entries == 0) {
-               r->cached_prod = libbpf_smp_load_acquire(r->producer);
-               entries = r->cached_prod - r->cached_cons;
-       }
-
-       return (entries > nb) ? nb : entries;
-}
-
-static inline __u32 xsk_ring_prod__reserve(struct xsk_ring_prod *prod, __u32 nb, __u32 *idx)
-{
-       if (xsk_prod_nb_free(prod, nb) < nb)
-               return 0;
-
-       *idx = prod->cached_prod;
-       prod->cached_prod += nb;
-
-       return nb;
-}
-
-static inline void xsk_ring_prod__submit(struct xsk_ring_prod *prod, __u32 nb)
-{
-       /* Make sure everything has been written to the ring before indicating
-        * this to the kernel by writing the producer pointer.
-        */
-       libbpf_smp_store_release(prod->producer, *prod->producer + nb);
-}
-
-static inline __u32 xsk_ring_cons__peek(struct xsk_ring_cons *cons, __u32 nb, __u32 *idx)
-{
-       __u32 entries = xsk_cons_nb_avail(cons, nb);
-
-       if (entries > 0) {
-               *idx = cons->cached_cons;
-               cons->cached_cons += entries;
-       }
-
-       return entries;
-}
-
-static inline void xsk_ring_cons__cancel(struct xsk_ring_cons *cons, __u32 nb)
-{
-       cons->cached_cons -= nb;
-}
-
-static inline void xsk_ring_cons__release(struct xsk_ring_cons *cons, __u32 nb)
-{
-       /* Make sure data has been read before indicating we are done
-        * with the entries by updating the consumer pointer.
-        */
-       libbpf_smp_store_release(cons->consumer, *cons->consumer + nb);
-
-}
-
-static inline void *xsk_umem__get_data(void *umem_area, __u64 addr)
-{
-       return &((char *)umem_area)[addr];
-}
-
-static inline __u64 xsk_umem__extract_addr(__u64 addr)
-{
-       return addr & XSK_UNALIGNED_BUF_ADDR_MASK;
-}
-
-static inline __u64 xsk_umem__extract_offset(__u64 addr)
-{
-       return addr >> XSK_UNALIGNED_BUF_OFFSET_SHIFT;
-}
-
-static inline __u64 xsk_umem__add_offset_to_addr(__u64 addr)
-{
-       return xsk_umem__extract_addr(addr) + xsk_umem__extract_offset(addr);
-}
-
-LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "AF_XDP support deprecated and moved to libxdp")
-int xsk_umem__fd(const struct xsk_umem *umem);
-LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "AF_XDP support deprecated and moved to libxdp")
-int xsk_socket__fd(const struct xsk_socket *xsk);
-
-#define XSK_RING_CONS__DEFAULT_NUM_DESCS      2048
-#define XSK_RING_PROD__DEFAULT_NUM_DESCS      2048
-#define XSK_UMEM__DEFAULT_FRAME_SHIFT    12 /* 4096 bytes */
-#define XSK_UMEM__DEFAULT_FRAME_SIZE     (1 << XSK_UMEM__DEFAULT_FRAME_SHIFT)
-#define XSK_UMEM__DEFAULT_FRAME_HEADROOM 0
-#define XSK_UMEM__DEFAULT_FLAGS 0
-
-struct xsk_umem_config {
-       __u32 fill_size;
-       __u32 comp_size;
-       __u32 frame_size;
-       __u32 frame_headroom;
-       __u32 flags;
-};
-
-LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "AF_XDP support deprecated and moved to libxdp")
-int xsk_setup_xdp_prog(int ifindex, int *xsks_map_fd);
-LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "AF_XDP support deprecated and moved to libxdp")
-int xsk_socket__update_xskmap(struct xsk_socket *xsk, int xsks_map_fd);
-
-/* Flags for the libbpf_flags field. */
-#define XSK_LIBBPF_FLAGS__INHIBIT_PROG_LOAD (1 << 0)
-
-struct xsk_socket_config {
-       __u32 rx_size;
-       __u32 tx_size;
-       __u32 libbpf_flags;
-       __u32 xdp_flags;
-       __u16 bind_flags;
-};
-
-/* Set config to NULL to get the default configuration. */
-LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "AF_XDP support deprecated and moved to libxdp")
-int xsk_umem__create(struct xsk_umem **umem,
-                    void *umem_area, __u64 size,
-                    struct xsk_ring_prod *fill,
-                    struct xsk_ring_cons *comp,
-                    const struct xsk_umem_config *config);
-LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "AF_XDP support deprecated and moved to libxdp")
-int xsk_umem__create_v0_0_2(struct xsk_umem **umem,
-                           void *umem_area, __u64 size,
-                           struct xsk_ring_prod *fill,
-                           struct xsk_ring_cons *comp,
-                           const struct xsk_umem_config *config);
-LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "AF_XDP support deprecated and moved to libxdp")
-int xsk_umem__create_v0_0_4(struct xsk_umem **umem,
-                           void *umem_area, __u64 size,
-                           struct xsk_ring_prod *fill,
-                           struct xsk_ring_cons *comp,
-                           const struct xsk_umem_config *config);
-LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "AF_XDP support deprecated and moved to libxdp")
-int xsk_socket__create(struct xsk_socket **xsk,
-                      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 *config);
-LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "AF_XDP support deprecated and moved to libxdp")
-int xsk_socket__create_shared(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,
-                             struct xsk_ring_prod *fill,
-                             struct xsk_ring_cons *comp,
-                             const struct xsk_socket_config *config);
-
-/* Returns 0 for success and -EBUSY if the umem is still in use. */
-LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "AF_XDP support deprecated and moved to libxdp")
-int xsk_umem__delete(struct xsk_umem *umem);
-LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "AF_XDP support deprecated and moved to libxdp")
-void xsk_socket__delete(struct xsk_socket *xsk);
-
-#ifdef __cplusplus
-} /* extern "C" */
-#endif
-
-#endif /* __LIBBPF_XSK_H */
index 4fbd88a8ed9e0bb181937ba728f0765aa0a8bb4a..e32a28fe8bc13af19265b460310c48cda73fed89 100644 (file)
@@ -230,6 +230,8 @@ $(OUTPUT)/xdping: $(TESTING_HELPERS)
 $(OUTPUT)/flow_dissector_load: $(TESTING_HELPERS)
 $(OUTPUT)/test_maps: $(TESTING_HELPERS)
 $(OUTPUT)/test_verifier: $(TESTING_HELPERS) $(CAP_HELPERS)
+$(OUTPUT)/xsk.o: $(BPFOBJ)
+$(OUTPUT)/xdpxceiver: $(OUTPUT)/xsk.o
 
 BPFTOOL ?= $(DEFAULT_BPFTOOL)
 $(DEFAULT_BPFTOOL): $(wildcard $(BPFTOOLDIR)/*.[ch] $(BPFTOOLDIR)/Makefile)    \
index e5992a6b5e09664c82c04a5bb5ce81b2ed0735a6..019c567b6b4e255728e52604e46423d9e602878a 100644 (file)
@@ -97,7 +97,7 @@
 #include <time.h>
 #include <unistd.h>
 #include <stdatomic.h>
-#include <bpf/xsk.h>
+#include "xsk.h"
 #include "xdpxceiver.h"
 #include "../kselftest.h"
 
diff --git a/tools/testing/selftests/bpf/xsk.c b/tools/testing/selftests/bpf/xsk.c
new file mode 100644 (file)
index 0000000..eb50c3f
--- /dev/null
@@ -0,0 +1,1264 @@
+// 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/kernel.h>
+#include <linux/list.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 <linux/if_link.h>
+
+#include <bpf/bpf.h>
+#include <bpf/libbpf.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
+
+#define pr_warn(fmt, ...) fprintf(stderr, fmt, ##__VA_ARGS__)
+
+enum xsk_prog {
+       XSK_PROG_FALLBACK,
+       XSK_PROG_REDIRECT_FLAGS,
+};
+
+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;
+       int prog_fd;
+       int link_fd;
+       int xsks_map_fd;
+       char ifname[IFNAMSIZ];
+       bool has_bpf_link;
+};
+
+struct xsk_socket {
+       struct xsk_ring_cons *rx;
+       struct xsk_ring_prod *tx;
+       __u64 outstanding_tx;
+       struct xsk_ctx *ctx;
+       struct xsk_socket_config config;
+       int fd;
+};
+
+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;
+}
+
+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;
+}
+
+struct xsk_umem_config_v1 {
+       __u32 fill_size;
+       __u32 comp_size;
+       __u32 frame_size;
+       __u32 frame_headroom;
+};
+
+static enum xsk_prog get_xsk_prog(void)
+{
+       enum xsk_prog detected = XSK_PROG_FALLBACK;
+       char data_in = 0, data_out;
+       struct bpf_insn insns[] = {
+               BPF_LD_MAP_FD(BPF_REG_1, 0),
+               BPF_MOV64_IMM(BPF_REG_2, 0),
+               BPF_MOV64_IMM(BPF_REG_3, XDP_PASS),
+               BPF_EMIT_CALL(BPF_FUNC_redirect_map),
+               BPF_EXIT_INSN(),
+       };
+       LIBBPF_OPTS(bpf_test_run_opts, opts,
+               .data_in = &data_in,
+               .data_size_in = 1,
+               .data_out = &data_out,
+       );
+
+       int prog_fd, map_fd, ret, insn_cnt = ARRAY_SIZE(insns);
+
+       map_fd = bpf_map_create(BPF_MAP_TYPE_XSKMAP, NULL, sizeof(int), sizeof(int), 1, NULL);
+       if (map_fd < 0)
+               return detected;
+
+       insns[0].imm = map_fd;
+
+       prog_fd = bpf_prog_load(BPF_PROG_TYPE_XDP, NULL, "GPL", insns, insn_cnt, NULL);
+       if (prog_fd < 0) {
+               close(map_fd);
+               return detected;
+       }
+
+       ret = bpf_prog_test_run_opts(prog_fd, &opts);
+       if (!ret && opts.retval == XDP_PASS)
+               detected = XSK_PROG_REDIRECT_FLAGS;
+       close(prog_fd);
+       close(map_fd);
+       return detected;
+}
+
+static int xsk_load_xdp_prog(struct xsk_socket *xsk)
+{
+       static const int log_buf_size = 16 * 1024;
+       struct xsk_ctx *ctx = xsk->ctx;
+       char log_buf[log_buf_size];
+       int prog_fd;
+
+       /* This is the fallback 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, ctx->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, ctx->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, ctx->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(),
+       };
+
+       /* This is the post-5.3 kernel C-program:
+        * SEC("xdp_sock") int xdp_sock_prog(struct xdp_md *ctx)
+        * {
+        *     return bpf_redirect_map(&xsks_map, ctx->rx_queue_index, XDP_PASS);
+        * }
+        */
+       struct bpf_insn prog_redirect_flags[] = {
+               /* r2 = *(u32 *)(r1 + 16) */
+               BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, 16),
+               /* r1 = xskmap[] */
+               BPF_LD_MAP_FD(BPF_REG_1, ctx->xsks_map_fd),
+               /* r3 = XDP_PASS */
+               BPF_MOV64_IMM(BPF_REG_3, 2),
+               /* call bpf_redirect_map */
+               BPF_EMIT_CALL(BPF_FUNC_redirect_map),
+               BPF_EXIT_INSN(),
+       };
+       size_t insns_cnt[] = {ARRAY_SIZE(prog),
+                             ARRAY_SIZE(prog_redirect_flags),
+       };
+       struct bpf_insn *progs[] = {prog, prog_redirect_flags};
+       enum xsk_prog option = get_xsk_prog();
+       LIBBPF_OPTS(bpf_prog_load_opts, opts,
+               .log_buf = log_buf,
+               .log_size = log_buf_size,
+       );
+
+       prog_fd = bpf_prog_load(BPF_PROG_TYPE_XDP, NULL, "LGPL-2.1 or BSD-2-Clause",
+                               progs[option], insns_cnt[option], &opts);
+       if (prog_fd < 0) {
+               pr_warn("BPF log buffer:\n%s", log_buf);
+               return prog_fd;
+       }
+
+       ctx->prog_fd = prog_fd;
+       return 0;
+}
+
+static int xsk_create_bpf_link(struct xsk_socket *xsk)
+{
+       DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts);
+       struct xsk_ctx *ctx = xsk->ctx;
+       __u32 prog_id = 0;
+       int link_fd;
+       int err;
+
+       err = bpf_xdp_query_id(ctx->ifindex, xsk->config.xdp_flags, &prog_id);
+       if (err) {
+               pr_warn("getting XDP prog id failed\n");
+               return err;
+       }
+
+       /* if there's a netlink-based XDP prog loaded on interface, bail out
+        * and ask user to do the removal by himself
+        */
+       if (prog_id) {
+               pr_warn("Netlink-based XDP prog detected, please unload it in order to launch AF_XDP prog\n");
+               return -EINVAL;
+       }
+
+       opts.flags = xsk->config.xdp_flags & ~(XDP_FLAGS_UPDATE_IF_NOEXIST | XDP_FLAGS_REPLACE);
+
+       link_fd = bpf_link_create(ctx->prog_fd, ctx->ifindex, BPF_XDP, &opts);
+       if (link_fd < 0) {
+               pr_warn("bpf_link_create failed: %s\n", strerror(errno));
+               return link_fd;
+       }
+
+       ctx->link_fd = link_fd;
+       return 0;
+}
+
+/* Copy up to sz - 1 bytes from zero-terminated src string and ensure that dst
+ * is zero-terminated string no matter what (unless sz == 0, in which case
+ * it's a no-op). It's conceptually close to FreeBSD's strlcpy(), but differs
+ * in what is returned. Given this is internal helper, it's trivial to extend
+ * this, when necessary. Use this instead of strncpy inside libbpf source code.
+ */
+static inline void libbpf_strlcpy(char *dst, const char *src, size_t sz)
+{
+        size_t i;
+
+        if (sz == 0)
+                return;
+
+        sz--;
+        for (i = 0; i < sz && src[i]; i++)
+                dst[i] = src[i];
+        dst[i] = '\0';
+}
+
+static int xsk_get_max_queues(struct xsk_socket *xsk)
+{
+       struct ethtool_channels channels = { .cmd = ETHTOOL_GCHANNELS };
+       struct xsk_ctx *ctx = xsk->ctx;
+       struct ifreq ifr = {};
+       int fd, err, ret;
+
+       fd = socket(AF_LOCAL, SOCK_DGRAM | SOCK_CLOEXEC, 0);
+       if (fd < 0)
+               return -errno;
+
+       ifr.ifr_data = (void *)&channels;
+       libbpf_strlcpy(ifr.ifr_name, ctx->ifname, IFNAMSIZ);
+       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)
+{
+       struct xsk_ctx *ctx = xsk->ctx;
+       int max_queues;
+       int fd;
+
+       max_queues = xsk_get_max_queues(xsk);
+       if (max_queues < 0)
+               return max_queues;
+
+       fd = bpf_map_create(BPF_MAP_TYPE_XSKMAP, "xsks_map",
+                           sizeof(int), sizeof(int), max_queues, NULL);
+       if (fd < 0)
+               return fd;
+
+       ctx->xsks_map_fd = fd;
+
+       return 0;
+}
+
+static void xsk_delete_bpf_maps(struct xsk_socket *xsk)
+{
+       struct xsk_ctx *ctx = xsk->ctx;
+
+       bpf_map_delete_elem(ctx->xsks_map_fd, &ctx->queue_id);
+       close(ctx->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 xsk_ctx *ctx = xsk->ctx;
+       struct bpf_map_info map_info;
+       int fd, err;
+
+       err = bpf_obj_get_info_by_fd(ctx->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(ctx->prog_fd, &prog_info, &prog_len);
+       if (err)
+               goto out_map_ids;
+
+       ctx->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;
+
+               memset(&map_info, 0, map_len);
+               err = bpf_obj_get_info_by_fd(fd, &map_info, &map_len);
+               if (err) {
+                       close(fd);
+                       continue;
+               }
+
+               if (!strncmp(map_info.name, "xsks_map", sizeof(map_info.name))) {
+                       ctx->xsks_map_fd = fd;
+                       break;
+               }
+
+               close(fd);
+       }
+
+       if (ctx->xsks_map_fd == -1)
+               err = -ENOENT;
+
+out_map_ids:
+       free(map_ids);
+       return err;
+}
+
+static int xsk_set_bpf_maps(struct xsk_socket *xsk)
+{
+       struct xsk_ctx *ctx = xsk->ctx;
+
+       return bpf_map_update_elem(ctx->xsks_map_fd, &ctx->queue_id,
+                                  &xsk->fd, 0);
+}
+
+static int xsk_link_lookup(int ifindex, __u32 *prog_id, int *link_fd)
+{
+       struct bpf_link_info link_info;
+       __u32 link_len;
+       __u32 id = 0;
+       int err;
+       int fd;
+
+       while (true) {
+               err = bpf_link_get_next_id(id, &id);
+               if (err) {
+                       if (errno == ENOENT) {
+                               err = 0;
+                               break;
+                       }
+                       pr_warn("can't get next link: %s\n", strerror(errno));
+                       break;
+               }
+
+               fd = bpf_link_get_fd_by_id(id);
+               if (fd < 0) {
+                       if (errno == ENOENT)
+                               continue;
+                       pr_warn("can't get link by id (%u): %s\n", id, strerror(errno));
+                       err = -errno;
+                       break;
+               }
+
+               link_len = sizeof(struct bpf_link_info);
+               memset(&link_info, 0, link_len);
+               err = bpf_obj_get_info_by_fd(fd, &link_info, &link_len);
+               if (err) {
+                       pr_warn("can't get link info: %s\n", strerror(errno));
+                       close(fd);
+                       break;
+               }
+               if (link_info.type == BPF_LINK_TYPE_XDP) {
+                       if (link_info.xdp.ifindex == ifindex) {
+                               *link_fd = fd;
+                               if (prog_id)
+                                       *prog_id = link_info.prog_id;
+                               break;
+                       }
+               }
+               close(fd);
+       }
+
+       return err;
+}
+
+static bool xsk_probe_bpf_link(void)
+{
+       LIBBPF_OPTS(bpf_link_create_opts, opts, .flags = XDP_FLAGS_SKB_MODE);
+       struct bpf_insn insns[2] = {
+               BPF_MOV64_IMM(BPF_REG_0, XDP_PASS),
+               BPF_EXIT_INSN()
+       };
+       int prog_fd, link_fd = -1, insn_cnt = ARRAY_SIZE(insns);
+       int ifindex_lo = 1;
+       bool ret = false;
+       int err;
+
+       err = xsk_link_lookup(ifindex_lo, NULL, &link_fd);
+       if (err)
+               return ret;
+
+       if (link_fd >= 0)
+               return true;
+
+       prog_fd = bpf_prog_load(BPF_PROG_TYPE_XDP, NULL, "GPL", insns, insn_cnt, NULL);
+       if (prog_fd < 0)
+               return ret;
+
+       link_fd = bpf_link_create(prog_fd, ifindex_lo, BPF_XDP, &opts);
+       close(prog_fd);
+
+       if (link_fd >= 0) {
+               ret = true;
+               close(link_fd);
+       }
+
+       return ret;
+}
+
+static int xsk_create_xsk_struct(int ifindex, struct xsk_socket *xsk)
+{
+       char ifname[IFNAMSIZ];
+       struct xsk_ctx *ctx;
+       char *interface;
+
+       ctx = calloc(1, sizeof(*ctx));
+       if (!ctx)
+               return -ENOMEM;
+
+       interface = if_indextoname(ifindex, &ifname[0]);
+       if (!interface) {
+               free(ctx);
+               return -errno;
+       }
+
+       ctx->ifindex = ifindex;
+       libbpf_strlcpy(ctx->ifname, ifname, IFNAMSIZ);
+
+       xsk->ctx = ctx;
+       xsk->ctx->has_bpf_link = xsk_probe_bpf_link();
+
+       return 0;
+}
+
+static int xsk_init_xdp_res(struct xsk_socket *xsk,
+                           int *xsks_map_fd)
+{
+       struct xsk_ctx *ctx = xsk->ctx;
+       int err;
+
+       err = xsk_create_bpf_maps(xsk);
+       if (err)
+               return err;
+
+       err = xsk_load_xdp_prog(xsk);
+       if (err)
+               goto err_load_xdp_prog;
+
+       if (ctx->has_bpf_link)
+               err = xsk_create_bpf_link(xsk);
+       else
+               err = bpf_xdp_attach(xsk->ctx->ifindex, ctx->prog_fd,
+                                    xsk->config.xdp_flags, NULL);
+
+       if (err)
+               goto err_attach_xdp_prog;
+
+       if (!xsk->rx)
+               return err;
+
+       err = xsk_set_bpf_maps(xsk);
+       if (err)
+               goto err_set_bpf_maps;
+
+       return err;
+
+err_set_bpf_maps:
+       if (ctx->has_bpf_link)
+               close(ctx->link_fd);
+       else
+               bpf_xdp_detach(ctx->ifindex, 0, NULL);
+err_attach_xdp_prog:
+       close(ctx->prog_fd);
+err_load_xdp_prog:
+       xsk_delete_bpf_maps(xsk);
+       return err;
+}
+
+static int xsk_lookup_xdp_res(struct xsk_socket *xsk, int *xsks_map_fd, int prog_id)
+{
+       struct xsk_ctx *ctx = xsk->ctx;
+       int err;
+
+       ctx->prog_fd = bpf_prog_get_fd_by_id(prog_id);
+       if (ctx->prog_fd < 0) {
+               err = -errno;
+               goto err_prog_fd;
+       }
+       err = xsk_lookup_bpf_maps(xsk);
+       if (err)
+               goto err_lookup_maps;
+
+       if (!xsk->rx)
+               return err;
+
+       err = xsk_set_bpf_maps(xsk);
+       if (err)
+               goto err_set_maps;
+
+       return err;
+
+err_set_maps:
+       close(ctx->xsks_map_fd);
+err_lookup_maps:
+       close(ctx->prog_fd);
+err_prog_fd:
+       if (ctx->has_bpf_link)
+               close(ctx->link_fd);
+       return err;
+}
+
+static int __xsk_setup_xdp_prog(struct xsk_socket *_xdp, int *xsks_map_fd)
+{
+       struct xsk_socket *xsk = _xdp;
+       struct xsk_ctx *ctx = xsk->ctx;
+       __u32 prog_id = 0;
+       int err;
+
+       if (ctx->has_bpf_link)
+               err = xsk_link_lookup(ctx->ifindex, &prog_id, &ctx->link_fd);
+       else
+               err = bpf_xdp_query_id(ctx->ifindex, xsk->config.xdp_flags, &prog_id);
+
+       if (err)
+               return err;
+
+       err = !prog_id ? xsk_init_xdp_res(xsk, xsks_map_fd) :
+                        xsk_lookup_xdp_res(xsk, xsks_map_fd, prog_id);
+
+       if (!err && xsks_map_fd)
+               *xsks_map_fd = ctx->xsks_map_fd;
+
+       return err;
+}
+
+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,
+                                     const char *ifname, __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;
+       libbpf_strlcpy(ctx->ifname, ifname, IFNAMSIZ);
+
+       ctx->fill = fill;
+       ctx->comp = comp;
+       list_add(&ctx->list, &umem->ctx_list);
+       return ctx;
+}
+
+static void xsk_destroy_xsk_struct(struct xsk_socket *xsk)
+{
+       free(xsk->ctx);
+       free(xsk);
+}
+
+int xsk_socket__update_xskmap(struct xsk_socket *xsk, int fd)
+{
+       xsk->ctx->xsks_map_fd = fd;
+       return xsk_set_bpf_maps(xsk);
+}
+
+int xsk_setup_xdp_prog(int ifindex, int *xsks_map_fd)
+{
+       struct xsk_socket *xsk;
+       int res;
+
+       xsk = calloc(1, sizeof(*xsk));
+       if (!xsk)
+               return -ENOMEM;
+
+       res = xsk_create_xsk_struct(ifindex, xsk);
+       if (res) {
+               free(xsk);
+               return -EINVAL;
+       }
+
+       res = __xsk_setup_xdp_prog(xsk, xsks_map_fd);
+
+       xsk_destroy_xsk_struct(xsk);
+
+       return res;
+}
+
+int xsk_socket__create_shared(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,
+                             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, ifindex;
+
+       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;
+
+       xsk->outstanding_tx = 0;
+       ifindex = if_nametoindex(ifname);
+       if (!ifindex) {
+               err = -errno;
+               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, ifname, queue_id,
+                                    fill, comp);
+               if (!ctx) {
+                       err = -ENOMEM;
+                       goto out_socket;
+               }
+       }
+       xsk->ctx = ctx;
+       xsk->ctx->has_bpf_link = xsk_probe_bpf_link();
+
+       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;
+       }
+
+       ctx->prog_fd = -1;
+
+       if (!(xsk->config.libbpf_flags & XSK_LIBBPF_FLAGS__INHIBIT_PROG_LOAD)) {
+               err = __xsk_setup_xdp_prog(xsk, NULL);
+               if (err)
+                       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, 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)
+{
+       if (!umem)
+               return -EFAULT;
+
+       return xsk_socket__create_shared(xsk_ptr, ifname, 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;
+       if (ctx->prog_fd != -1) {
+               xsk_delete_bpf_maps(xsk);
+               close(ctx->prog_fd);
+               if (ctx->has_bpf_link)
+                       close(ctx->link_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_put_ctx(ctx, true);
+
+       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);
+}
diff --git a/tools/testing/selftests/bpf/xsk.h b/tools/testing/selftests/bpf/xsk.h
new file mode 100644 (file)
index 0000000..915e713
--- /dev/null
@@ -0,0 +1,315 @@
+/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
+
+/*
+ * AF_XDP user-space access library.
+ *
+ * Copyright (c) 2018 - 2019 Intel Corporation.
+ * Copyright (c) 2019 Facebook
+ *
+ * Author(s): Magnus Karlsson <magnus.karlsson@intel.com>
+ */
+
+#ifndef __XSK_H
+#define __XSK_H
+
+#include <stdio.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <linux/if_xdp.h>
+
+#include <bpf/libbpf.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* This whole API has been deprecated and moved to libxdp that can be found at
+ * https://github.com/xdp-project/xdp-tools. The APIs are exactly the same so
+ * it should just be linking with libxdp instead of libbpf for this set of
+ * functionality. If not, please submit a bug report on the aforementioned page.
+ */
+
+/* Load-Acquire Store-Release barriers used by the XDP socket
+ * library. The following macros should *NOT* be considered part of
+ * the xsk.h API, and is subject to change anytime.
+ *
+ * LIBRARY INTERNAL
+ */
+
+#define __XSK_READ_ONCE(x) (*(volatile typeof(x) *)&x)
+#define __XSK_WRITE_ONCE(x, v) (*(volatile typeof(x) *)&x) = (v)
+
+#if defined(__i386__) || defined(__x86_64__)
+# define libbpf_smp_store_release(p, v)                                        \
+       do {                                                            \
+               asm volatile("" : : : "memory");                        \
+               __XSK_WRITE_ONCE(*p, v);                                \
+       } while (0)
+# define libbpf_smp_load_acquire(p)                                    \
+       ({                                                              \
+               typeof(*p) ___p1 = __XSK_READ_ONCE(*p);                 \
+               asm volatile("" : : : "memory");                        \
+               ___p1;                                                  \
+       })
+#elif defined(__aarch64__)
+# define libbpf_smp_store_release(p, v)                                        \
+               asm volatile ("stlr %w1, %0" : "=Q" (*p) : "r" (v) : "memory")
+# define libbpf_smp_load_acquire(p)                                    \
+       ({                                                              \
+               typeof(*p) ___p1;                                       \
+               asm volatile ("ldar %w0, %1"                            \
+                             : "=r" (___p1) : "Q" (*p) : "memory");    \
+               ___p1;                                                  \
+       })
+#elif defined(__riscv)
+# define libbpf_smp_store_release(p, v)                                        \
+       do {                                                            \
+               asm volatile ("fence rw,w" : : : "memory");             \
+               __XSK_WRITE_ONCE(*p, v);                                \
+       } while (0)
+# define libbpf_smp_load_acquire(p)                                    \
+       ({                                                              \
+               typeof(*p) ___p1 = __XSK_READ_ONCE(*p);                 \
+               asm volatile ("fence r,rw" : : : "memory");             \
+               ___p1;                                                  \
+       })
+#endif
+
+#ifndef libbpf_smp_store_release
+#define libbpf_smp_store_release(p, v)                                 \
+       do {                                                            \
+               __sync_synchronize();                                   \
+               __XSK_WRITE_ONCE(*p, v);                                \
+       } while (0)
+#endif
+
+#ifndef libbpf_smp_load_acquire
+#define libbpf_smp_load_acquire(p)                                     \
+       ({                                                              \
+               typeof(*p) ___p1 = __XSK_READ_ONCE(*p);                 \
+               __sync_synchronize();                                   \
+               ___p1;                                                  \
+       })
+#endif
+
+/* LIBRARY INTERNAL -- END */
+
+/* Do not access these members directly. Use the functions below. */
+#define DEFINE_XSK_RING(name) \
+struct name { \
+       __u32 cached_prod; \
+       __u32 cached_cons; \
+       __u32 mask; \
+       __u32 size; \
+       __u32 *producer; \
+       __u32 *consumer; \
+       void *ring; \
+       __u32 *flags; \
+}
+
+DEFINE_XSK_RING(xsk_ring_prod);
+DEFINE_XSK_RING(xsk_ring_cons);
+
+/* For a detailed explanation on the memory barriers associated with the
+ * ring, please take a look at net/xdp/xsk_queue.h.
+ */
+
+struct xsk_umem;
+struct xsk_socket;
+
+static inline __u64 *xsk_ring_prod__fill_addr(struct xsk_ring_prod *fill,
+                                             __u32 idx)
+{
+       __u64 *addrs = (__u64 *)fill->ring;
+
+       return &addrs[idx & fill->mask];
+}
+
+static inline const __u64 *
+xsk_ring_cons__comp_addr(const struct xsk_ring_cons *comp, __u32 idx)
+{
+       const __u64 *addrs = (const __u64 *)comp->ring;
+
+       return &addrs[idx & comp->mask];
+}
+
+static inline struct xdp_desc *xsk_ring_prod__tx_desc(struct xsk_ring_prod *tx,
+                                                     __u32 idx)
+{
+       struct xdp_desc *descs = (struct xdp_desc *)tx->ring;
+
+       return &descs[idx & tx->mask];
+}
+
+static inline const struct xdp_desc *
+xsk_ring_cons__rx_desc(const struct xsk_ring_cons *rx, __u32 idx)
+{
+       const struct xdp_desc *descs = (const struct xdp_desc *)rx->ring;
+
+       return &descs[idx & rx->mask];
+}
+
+static inline int xsk_ring_prod__needs_wakeup(const struct xsk_ring_prod *r)
+{
+       return *r->flags & XDP_RING_NEED_WAKEUP;
+}
+
+static inline __u32 xsk_prod_nb_free(struct xsk_ring_prod *r, __u32 nb)
+{
+       __u32 free_entries = r->cached_cons - r->cached_prod;
+
+       if (free_entries >= nb)
+               return free_entries;
+
+       /* Refresh the local tail pointer.
+        * cached_cons is r->size bigger than the real consumer pointer so
+        * that this addition can be avoided in the more frequently
+        * executed code that computs free_entries in the beginning of
+        * this function. Without this optimization it whould have been
+        * free_entries = r->cached_prod - r->cached_cons + r->size.
+        */
+       r->cached_cons = libbpf_smp_load_acquire(r->consumer);
+       r->cached_cons += r->size;
+
+       return r->cached_cons - r->cached_prod;
+}
+
+static inline __u32 xsk_cons_nb_avail(struct xsk_ring_cons *r, __u32 nb)
+{
+       __u32 entries = r->cached_prod - r->cached_cons;
+
+       if (entries == 0) {
+               r->cached_prod = libbpf_smp_load_acquire(r->producer);
+               entries = r->cached_prod - r->cached_cons;
+       }
+
+       return (entries > nb) ? nb : entries;
+}
+
+static inline __u32 xsk_ring_prod__reserve(struct xsk_ring_prod *prod, __u32 nb, __u32 *idx)
+{
+       if (xsk_prod_nb_free(prod, nb) < nb)
+               return 0;
+
+       *idx = prod->cached_prod;
+       prod->cached_prod += nb;
+
+       return nb;
+}
+
+static inline void xsk_ring_prod__submit(struct xsk_ring_prod *prod, __u32 nb)
+{
+       /* Make sure everything has been written to the ring before indicating
+        * this to the kernel by writing the producer pointer.
+        */
+       libbpf_smp_store_release(prod->producer, *prod->producer + nb);
+}
+
+static inline __u32 xsk_ring_cons__peek(struct xsk_ring_cons *cons, __u32 nb, __u32 *idx)
+{
+       __u32 entries = xsk_cons_nb_avail(cons, nb);
+
+       if (entries > 0) {
+               *idx = cons->cached_cons;
+               cons->cached_cons += entries;
+       }
+
+       return entries;
+}
+
+static inline void xsk_ring_cons__cancel(struct xsk_ring_cons *cons, __u32 nb)
+{
+       cons->cached_cons -= nb;
+}
+
+static inline void xsk_ring_cons__release(struct xsk_ring_cons *cons, __u32 nb)
+{
+       /* Make sure data has been read before indicating we are done
+        * with the entries by updating the consumer pointer.
+        */
+       libbpf_smp_store_release(cons->consumer, *cons->consumer + nb);
+
+}
+
+static inline void *xsk_umem__get_data(void *umem_area, __u64 addr)
+{
+       return &((char *)umem_area)[addr];
+}
+
+static inline __u64 xsk_umem__extract_addr(__u64 addr)
+{
+       return addr & XSK_UNALIGNED_BUF_ADDR_MASK;
+}
+
+static inline __u64 xsk_umem__extract_offset(__u64 addr)
+{
+       return addr >> XSK_UNALIGNED_BUF_OFFSET_SHIFT;
+}
+
+static inline __u64 xsk_umem__add_offset_to_addr(__u64 addr)
+{
+       return xsk_umem__extract_addr(addr) + xsk_umem__extract_offset(addr);
+}
+
+int xsk_umem__fd(const struct xsk_umem *umem);
+int xsk_socket__fd(const struct xsk_socket *xsk);
+
+#define XSK_RING_CONS__DEFAULT_NUM_DESCS      2048
+#define XSK_RING_PROD__DEFAULT_NUM_DESCS      2048
+#define XSK_UMEM__DEFAULT_FRAME_SHIFT    12 /* 4096 bytes */
+#define XSK_UMEM__DEFAULT_FRAME_SIZE     (1 << XSK_UMEM__DEFAULT_FRAME_SHIFT)
+#define XSK_UMEM__DEFAULT_FRAME_HEADROOM 0
+#define XSK_UMEM__DEFAULT_FLAGS 0
+
+struct xsk_umem_config {
+       __u32 fill_size;
+       __u32 comp_size;
+       __u32 frame_size;
+       __u32 frame_headroom;
+       __u32 flags;
+};
+
+int xsk_setup_xdp_prog(int ifindex, int *xsks_map_fd);
+int xsk_socket__update_xskmap(struct xsk_socket *xsk, int xsks_map_fd);
+
+/* Flags for the libbpf_flags field. */
+#define XSK_LIBBPF_FLAGS__INHIBIT_PROG_LOAD (1 << 0)
+
+struct xsk_socket_config {
+       __u32 rx_size;
+       __u32 tx_size;
+       __u32 libbpf_flags;
+       __u32 xdp_flags;
+       __u16 bind_flags;
+};
+
+/* Set config to NULL to get the default configuration. */
+int xsk_umem__create(struct xsk_umem **umem,
+                    void *umem_area, __u64 size,
+                    struct xsk_ring_prod *fill,
+                    struct xsk_ring_cons *comp,
+                    const struct xsk_umem_config *config);
+int xsk_socket__create(struct xsk_socket **xsk,
+                      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 *config);
+int xsk_socket__create_shared(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,
+                             struct xsk_ring_prod *fill,
+                             struct xsk_ring_cons *comp,
+                             const struct xsk_socket_config *config);
+
+/* Returns 0 for success and -EBUSY if the umem is still in use. */
+int xsk_umem__delete(struct xsk_umem *umem);
+void xsk_socket__delete(struct xsk_socket *xsk);
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#endif /* __XSK_H */