From 50a3e678b58ae9535f9e536f2889649b624943c3 Mon Sep 17 00:00:00 2001 From: Toke Høiland-Jørgensen Date: Wed, 25 Mar 2020 18:23:27 +0100 Subject: tools: Add EXPECTED_FD-related definitions in if_link.h MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This adds the IFLA_XDP_EXPECTED_FD netlink attribute definition and the XDP_FLAGS_REPLACE flag to if_link.h in tools/include. Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/158515700747.92963.8615391897417388586.stgit@toke.dk --- tools/include/uapi/linux/if_link.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'tools') diff --git a/tools/include/uapi/linux/if_link.h b/tools/include/uapi/linux/if_link.h index 024af2d1d0af..b1ec7c949e6a 100644 --- a/tools/include/uapi/linux/if_link.h +++ b/tools/include/uapi/linux/if_link.h @@ -960,11 +960,12 @@ enum { #define XDP_FLAGS_SKB_MODE (1U << 1) #define XDP_FLAGS_DRV_MODE (1U << 2) #define XDP_FLAGS_HW_MODE (1U << 3) +#define XDP_FLAGS_REPLACE (1U << 4) #define XDP_FLAGS_MODES (XDP_FLAGS_SKB_MODE | \ XDP_FLAGS_DRV_MODE | \ XDP_FLAGS_HW_MODE) #define XDP_FLAGS_MASK (XDP_FLAGS_UPDATE_IF_NOEXIST | \ - XDP_FLAGS_MODES) + XDP_FLAGS_MODES | XDP_FLAGS_REPLACE) /* These are stored into IFLA_XDP_ATTACHED on dump. */ enum { @@ -984,6 +985,7 @@ enum { IFLA_XDP_DRV_PROG_ID, IFLA_XDP_SKB_PROG_ID, IFLA_XDP_HW_PROG_ID, + IFLA_XDP_EXPECTED_FD, __IFLA_XDP_MAX, }; -- cgit From bd5ca3ef93cd8fb7e913f15eeb78e67a0d802274 Mon Sep 17 00:00:00 2001 From: Toke Høiland-Jørgensen Date: Wed, 25 Mar 2020 18:23:28 +0100 Subject: libbpf: Add function to set link XDP fd while specifying old program MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This adds a new function to set the XDP fd while specifying the FD of the program to replace, using the newly added IFLA_XDP_EXPECTED_FD netlink parameter. The new function uses the opts struct mechanism to be extendable in the future. Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/158515700857.92963.7052131201257841700.stgit@toke.dk --- tools/lib/bpf/libbpf.h | 8 ++++++++ tools/lib/bpf/libbpf.map | 1 + tools/lib/bpf/netlink.c | 34 +++++++++++++++++++++++++++++++++- 3 files changed, 42 insertions(+), 1 deletion(-) (limited to 'tools') diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index d38d7a629417..bf7a35a9556d 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -444,7 +444,15 @@ struct xdp_link_info { __u8 attach_mode; }; +struct bpf_xdp_set_link_opts { + size_t sz; + __u32 old_fd; +}; +#define bpf_xdp_set_link_opts__last_field old_fd + LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags); +LIBBPF_API int bpf_set_link_xdp_fd_opts(int ifindex, int fd, __u32 flags, + const struct bpf_xdp_set_link_opts *opts); LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags); LIBBPF_API int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info, size_t info_size, __u32 flags); diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index 5129283c0284..dcc87db3ca8a 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -244,4 +244,5 @@ LIBBPF_0.0.8 { bpf_link__pin_path; bpf_link__unpin; bpf_program__set_attach_target; + bpf_set_link_xdp_fd_opts; } LIBBPF_0.0.7; diff --git a/tools/lib/bpf/netlink.c b/tools/lib/bpf/netlink.c index 431bd25c6cdb..18b5319025e1 100644 --- a/tools/lib/bpf/netlink.c +++ b/tools/lib/bpf/netlink.c @@ -132,7 +132,8 @@ done: return ret; } -int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags) +static int __bpf_set_link_xdp_fd_replace(int ifindex, int fd, int old_fd, + __u32 flags) { int sock, seq = 0, ret; struct nlattr *nla, *nla_xdp; @@ -178,6 +179,14 @@ int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags) nla->nla_len += nla_xdp->nla_len; } + if (flags & XDP_FLAGS_REPLACE) { + nla_xdp = (struct nlattr *)((char *)nla + nla->nla_len); + nla_xdp->nla_type = IFLA_XDP_EXPECTED_FD; + nla_xdp->nla_len = NLA_HDRLEN + sizeof(old_fd); + memcpy((char *)nla_xdp + NLA_HDRLEN, &old_fd, sizeof(old_fd)); + nla->nla_len += nla_xdp->nla_len; + } + req.nh.nlmsg_len += NLA_ALIGN(nla->nla_len); if (send(sock, &req, req.nh.nlmsg_len, 0) < 0) { @@ -191,6 +200,29 @@ cleanup: return ret; } +int bpf_set_link_xdp_fd_opts(int ifindex, int fd, __u32 flags, + const struct bpf_xdp_set_link_opts *opts) +{ + int old_fd = -1; + + if (!OPTS_VALID(opts, bpf_xdp_set_link_opts)) + return -EINVAL; + + if (OPTS_HAS(opts, old_fd)) { + old_fd = OPTS_GET(opts, old_fd, -1); + flags |= XDP_FLAGS_REPLACE; + } + + return __bpf_set_link_xdp_fd_replace(ifindex, fd, + old_fd, + flags); +} + +int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags) +{ + return __bpf_set_link_xdp_fd_replace(ifindex, fd, 0, flags); +} + static int __dump_link_nlmsg(struct nlmsghdr *nlh, libbpf_dump_nlmsg_t dump_link_nlmsg, void *cookie) { -- cgit From 87854a0b57b34c52e172109b1d3949fc639b6474 Mon Sep 17 00:00:00 2001 From: Toke Høiland-Jørgensen Date: Wed, 25 Mar 2020 18:23:29 +0100 Subject: selftests/bpf: Add tests for attaching XDP programs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This adds tests for the various replacement operations using IFLA_XDP_EXPECTED_FD. Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/158515700967.92963.15098921624731968356.stgit@toke.dk --- .../testing/selftests/bpf/prog_tests/xdp_attach.c | 62 ++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/xdp_attach.c (limited to 'tools') diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_attach.c b/tools/testing/selftests/bpf/prog_tests/xdp_attach.c new file mode 100644 index 000000000000..05b294d6b923 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/xdp_attach.c @@ -0,0 +1,62 @@ +// SPDX-License-Identifier: GPL-2.0 +#include + +#define IFINDEX_LO 1 +#define XDP_FLAGS_REPLACE (1U << 4) + +void test_xdp_attach(void) +{ + struct bpf_object *obj1, *obj2, *obj3; + const char *file = "./test_xdp.o"; + int err, fd1, fd2, fd3; + __u32 duration = 0; + DECLARE_LIBBPF_OPTS(bpf_xdp_set_link_opts, opts, + .old_fd = -1); + + err = bpf_prog_load(file, BPF_PROG_TYPE_XDP, &obj1, &fd1); + if (CHECK_FAIL(err)) + return; + err = bpf_prog_load(file, BPF_PROG_TYPE_XDP, &obj2, &fd2); + if (CHECK_FAIL(err)) + goto out_1; + err = bpf_prog_load(file, BPF_PROG_TYPE_XDP, &obj3, &fd3); + if (CHECK_FAIL(err)) + goto out_2; + + err = bpf_set_link_xdp_fd_opts(IFINDEX_LO, fd1, XDP_FLAGS_REPLACE, + &opts); + if (CHECK(err, "load_ok", "initial load failed")) + goto out_close; + + err = bpf_set_link_xdp_fd_opts(IFINDEX_LO, fd2, XDP_FLAGS_REPLACE, + &opts); + if (CHECK(!err, "load_fail", "load with expected id didn't fail")) + goto out; + + opts.old_fd = fd1; + err = bpf_set_link_xdp_fd_opts(IFINDEX_LO, fd2, 0, &opts); + if (CHECK(err, "replace_ok", "replace valid old_fd failed")) + goto out; + + err = bpf_set_link_xdp_fd_opts(IFINDEX_LO, fd3, 0, &opts); + if (CHECK(!err, "replace_fail", "replace invalid old_fd didn't fail")) + goto out; + + err = bpf_set_link_xdp_fd_opts(IFINDEX_LO, -1, 0, &opts); + if (CHECK(!err, "remove_fail", "remove invalid old_fd didn't fail")) + goto out; + + opts.old_fd = fd2; + err = bpf_set_link_xdp_fd_opts(IFINDEX_LO, -1, 0, &opts); + if (CHECK(err, "remove_ok", "remove valid old_fd failed")) + goto out; + +out: + bpf_set_link_xdp_fd(IFINDEX_LO, -1, 0); +out_close: + bpf_object__close(obj3); +out_2: + bpf_object__close(obj2); +out_1: + bpf_object__close(obj1); +} -- cgit