@@ -2,6 +2,7 @@
* Copyright(c) 2020 Intel Corporation.
*/
+#include <bpf/bpf.h>
#include <bpf/xsk.h>
#include <linux/version.h>
#include <poll.h>
@@ -54,3 +55,126 @@ tx_syscall_needed(struct xsk_ring_prod *q __rte_unused)
return 1;
}
#endif
+
+#ifdef RTE_LIBRTE_AF_XDP_PMD_BPF_LINK
+static int link_lookup(int ifindex, 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;
+ }
+ break;
+ }
+
+ fd = bpf_link_get_fd_by_id(id);
+ if (fd < 0) {
+ if (errno == ENOENT)
+ continue;
+ 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) {
+ close(fd);
+ break;
+ }
+ if (link_info.type == BPF_LINK_TYPE_XDP) {
+ if ((int)link_info.xdp.ifindex == ifindex) {
+ *link_fd = fd;
+ break;
+ }
+ }
+ close(fd);
+ }
+
+ return err;
+}
+
+static bool probe_bpf_link(void)
+{
+ DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts,
+ .flags = XDP_FLAGS_SKB_MODE);
+ struct bpf_load_program_attr prog_attr;
+ struct bpf_insn insns[2];
+ int prog_fd, link_fd = -1;
+ int ifindex_lo = 1;
+ bool ret = false;
+ int err;
+
+ err = link_lookup(ifindex_lo, &link_fd);
+ if (err)
+ return ret;
+
+ if (link_fd >= 0)
+ return true;
+
+ /* BPF_MOV64_IMM(BPF_REG_0, XDP_PASS), */
+ insns[0].code = BPF_ALU64 | BPF_MOV | BPF_K;
+ insns[0].dst_reg = BPF_REG_0;
+ insns[0].imm = XDP_PASS;
+
+ /* BPF_EXIT_INSN() */
+ insns[1].code = BPF_JMP | BPF_EXIT;
+
+ memset(&prog_attr, 0, sizeof(prog_attr));
+ prog_attr.prog_type = BPF_PROG_TYPE_XDP;
+ prog_attr.insns = insns;
+ prog_attr.insns_cnt = RTE_DIM(insns);
+ prog_attr.license = "GPL";
+
+ prog_fd = bpf_load_program_xattr(&prog_attr, NULL, 0);
+ 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 link_xdp_program(int if_index, int prog_fd, bool use_bpf_link)
+{
+ DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts);
+ int link_fd, ret = 0;
+
+ if (!use_bpf_link)
+ return bpf_set_link_xdp_fd(if_index, prog_fd,
+ XDP_FLAGS_UPDATE_IF_NOEXIST);
+
+ opts.flags = 0;
+ link_fd = bpf_link_create(prog_fd, if_index, BPF_XDP, &opts);
+ if (link_fd < 0)
+ ret = -1;
+
+ return ret;
+}
+#else
+static bool probe_bpf_link(void)
+{
+ return false;
+}
+
+static int link_xdp_program(int if_index, int prog_fd,
+ bool use_bpf_link __rte_unused)
+{
+ return bpf_set_link_xdp_fd(if_index, prog_fd,
+ XDP_FLAGS_UPDATE_IF_NOEXIST);
+}
+#endif
@@ -16,11 +16,18 @@ endif
if bpf_dep.found() and cc.has_header('bpf/xsk.h') and cc.has_header('linux/if_xdp.h')
ext_deps += bpf_dep
+ # check for libbpf shared umem APIs
bpf_ver_dep = dependency('libbpf', version : '>=0.2.0',
required: false, method: 'pkg-config')
if bpf_ver_dep.found()
dpdk_conf.set('RTE_LIBRTE_AF_XDP_PMD_SHARED_UMEM', 1)
endif
+ # check for libbpf bpf link support
+ bpf_link_dep = dependency('libbpf', version : '>=0.4.0',
+ required: false, method: 'pkg-config')
+ if bpf_link_dep.found()
+ dpdk_conf.set('RTE_LIBRTE_AF_XDP_PMD_BPF_LINK', 1)
+ endif
else
build = false
reason = 'missing dependency, "libbpf"'
@@ -138,6 +138,7 @@ struct pmd_internals {
bool shared_umem;
char prog_path[PATH_MAX];
bool custom_prog_configured;
+ bool use_bpf_link;
struct rte_ether_addr eth_addr;
@@ -971,7 +972,8 @@ eth_dev_close(struct rte_eth_dev *dev)
*/
dev->data->mac_addrs = NULL;
- remove_xdp_program(internals);
+ if (!internals->use_bpf_link)
+ remove_xdp_program(internals);
if (internals->shared_umem) {
struct internal_list *list;
@@ -1146,7 +1148,7 @@ xsk_umem_info *xdp_umem_configure(struct pmd_internals *internals,
}
static int
-load_custom_xdp_prog(const char *prog_path, int if_index)
+load_custom_xdp_prog(const char *prog_path, int if_index, bool use_bpf_link)
{
int ret, prog_fd = -1;
struct bpf_object *obj;
@@ -1170,8 +1172,7 @@ load_custom_xdp_prog(const char *prog_path, int if_index)
}
/* Link the program with the given network device */
- ret = bpf_set_link_xdp_fd(if_index, prog_fd,
- XDP_FLAGS_UPDATE_IF_NOEXIST);
+ ret = link_xdp_program(if_index, prog_fd, use_bpf_link);
if (ret) {
AF_XDP_LOG(ERR, "Failed to set prog fd %d on interface\n",
prog_fd);
@@ -1271,7 +1272,8 @@ xsk_configure(struct pmd_internals *internals, struct pkt_rx_queue *rxq,
if (strnlen(internals->prog_path, PATH_MAX) &&
!internals->custom_prog_configured) {
ret = load_custom_xdp_prog(internals->prog_path,
- internals->if_index);
+ internals->if_index,
+ internals->use_bpf_link);
if (ret) {
AF_XDP_LOG(ERR, "Failed to load custom XDP program %s\n",
internals->prog_path);
@@ -1688,6 +1690,7 @@ init_internals(struct rte_vdev_device *dev, const char *if_name,
strlcpy(internals->if_name, if_name, IFNAMSIZ);
strlcpy(internals->prog_path, prog_path, PATH_MAX);
internals->custom_prog_configured = 0;
+ internals->use_bpf_link = probe_bpf_link();
#ifndef ETH_AF_XDP_SHARED_UMEM
if (shared_umem) {