From d0cabbb021bee5c4b831a0235af9534ad07f8d3d Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Thu, 10 May 2018 10:24:40 -0700 Subject: tools: bpf: move the event reading loop to libbpf There are two copies of event reading loop - in bpftool and trace_helpers "library". Consolidate them and move the code to libbpf. Return codes from trace_helpers are kept, but renamed to include LIBBPF prefix. Suggested-by: Alexei Starovoitov Signed-off-by: Jakub Kicinski Reviewed-by: Quentin Monnet Signed-off-by: Daniel Borkmann --- tools/lib/bpf/libbpf.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) (limited to 'tools/lib/bpf/libbpf.c') diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 7bcdca13083a..ce96f1fe3f37 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include #include @@ -2210,3 +2211,63 @@ int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, *prog_fd = bpf_program__fd(first_prog); return 0; } + +enum bpf_perf_event_ret +bpf_perf_event_read_simple(void *mem, unsigned long size, + unsigned long page_size, void **buf, size_t *buf_len, + bpf_perf_event_print_t fn, void *priv) +{ + volatile struct perf_event_mmap_page *header = mem; + __u64 data_tail = header->data_tail; + __u64 data_head = header->data_head; + void *base, *begin, *end; + int ret; + + asm volatile("" ::: "memory"); /* in real code it should be smp_rmb() */ + if (data_head == data_tail) + return LIBBPF_PERF_EVENT_CONT; + + base = ((char *)header) + page_size; + + begin = base + data_tail % size; + end = base + data_head % size; + + while (begin != end) { + struct perf_event_header *ehdr; + + ehdr = begin; + if (begin + ehdr->size > base + size) { + long len = base + size - begin; + + if (*buf_len < ehdr->size) { + free(*buf); + *buf = malloc(ehdr->size); + if (!*buf) { + ret = LIBBPF_PERF_EVENT_ERROR; + break; + } + *buf_len = ehdr->size; + } + + memcpy(*buf, begin, len); + memcpy(*buf + len, base, ehdr->size - len); + ehdr = (void *)*buf; + begin = base + ehdr->size - len; + } else if (begin + ehdr->size == base + size) { + begin = base; + } else { + begin += ehdr->size; + } + + ret = fn(ehdr, priv); + if (ret != LIBBPF_PERF_EVENT_CONT) + break; + + data_tail += ehdr->size; + } + + __sync_synchronize(); /* smp_mb() */ + header->data_tail = data_tail; + + return ret; +} -- cgit v1.2.3 From 17387dd5ac2c9c4e5f7d38b5affcd70e059f0a8c Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Thu, 10 May 2018 10:24:42 -0700 Subject: tools: bpf: don't complain about no kernel version for networking code BPF programs only have to specify the target kernel version for tracing related hooks, in networking world that requirement does not really apply. Loosen the checks in libbpf to reflect that. bpf_object__open() users will continue to see the error for backward compatibility (and because prog_type is not available there). Error code for NULL file name is changed from ENOENT to EINVAL, as it seems more appropriate, hopefully, that's an OK change. Signed-off-by: Jakub Kicinski Reviewed-by: Quentin Monnet Signed-off-by: Daniel Borkmann --- tools/lib/bpf/libbpf.c | 46 +++++++++++++++++++++++++++++++++++++++------- 1 file changed, 39 insertions(+), 7 deletions(-) (limited to 'tools/lib/bpf/libbpf.c') diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index ce96f1fe3f37..df54c4c9e48a 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -1438,9 +1438,37 @@ bpf_object__load_progs(struct bpf_object *obj) return 0; } -static int bpf_object__validate(struct bpf_object *obj) +static bool bpf_prog_type__needs_kver(enum bpf_prog_type type) +{ + switch (type) { + case BPF_PROG_TYPE_SOCKET_FILTER: + case BPF_PROG_TYPE_SCHED_CLS: + case BPF_PROG_TYPE_SCHED_ACT: + case BPF_PROG_TYPE_XDP: + case BPF_PROG_TYPE_CGROUP_SKB: + case BPF_PROG_TYPE_CGROUP_SOCK: + case BPF_PROG_TYPE_LWT_IN: + case BPF_PROG_TYPE_LWT_OUT: + case BPF_PROG_TYPE_LWT_XMIT: + case BPF_PROG_TYPE_SOCK_OPS: + case BPF_PROG_TYPE_SK_SKB: + case BPF_PROG_TYPE_CGROUP_DEVICE: + case BPF_PROG_TYPE_SK_MSG: + case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: + return false; + case BPF_PROG_TYPE_UNSPEC: + case BPF_PROG_TYPE_KPROBE: + case BPF_PROG_TYPE_TRACEPOINT: + case BPF_PROG_TYPE_PERF_EVENT: + case BPF_PROG_TYPE_RAW_TRACEPOINT: + default: + return true; + } +} + +static int bpf_object__validate(struct bpf_object *obj, bool needs_kver) { - if (obj->kern_version == 0) { + if (needs_kver && obj->kern_version == 0) { pr_warning("%s doesn't provide kernel version\n", obj->path); return -LIBBPF_ERRNO__KVERSION; @@ -1449,7 +1477,8 @@ static int bpf_object__validate(struct bpf_object *obj) } static struct bpf_object * -__bpf_object__open(const char *path, void *obj_buf, size_t obj_buf_sz) +__bpf_object__open(const char *path, void *obj_buf, size_t obj_buf_sz, + bool needs_kver) { struct bpf_object *obj; int err; @@ -1467,7 +1496,7 @@ __bpf_object__open(const char *path, void *obj_buf, size_t obj_buf_sz) CHECK_ERR(bpf_object__check_endianness(obj), err, out); CHECK_ERR(bpf_object__elf_collect(obj), err, out); CHECK_ERR(bpf_object__collect_reloc(obj), err, out); - CHECK_ERR(bpf_object__validate(obj), err, out); + CHECK_ERR(bpf_object__validate(obj, needs_kver), err, out); bpf_object__elf_finish(obj); return obj; @@ -1484,7 +1513,7 @@ struct bpf_object *bpf_object__open(const char *path) pr_debug("loading %s\n", path); - return __bpf_object__open(path, NULL, 0); + return __bpf_object__open(path, NULL, 0, true); } struct bpf_object *bpf_object__open_buffer(void *obj_buf, @@ -1507,7 +1536,7 @@ struct bpf_object *bpf_object__open_buffer(void *obj_buf, pr_debug("loading object '%s' from buffer\n", name); - return __bpf_object__open(name, obj_buf, obj_buf_sz); + return __bpf_object__open(name, obj_buf, obj_buf_sz, true); } int bpf_object__unload(struct bpf_object *obj) @@ -2164,8 +2193,11 @@ int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, if (!attr) return -EINVAL; + if (!attr->file) + return -EINVAL; - obj = bpf_object__open(attr->file); + obj = __bpf_object__open(attr->file, NULL, 0, + bpf_prog_type__needs_kver(attr->prog_type)); if (IS_ERR(obj)) return -ENOENT; -- cgit v1.2.3 From f0307a7ed17fa8925321a4f58f5ca56eeedd4fa3 Mon Sep 17 00:00:00 2001 From: David Beckett Date: Wed, 16 May 2018 14:02:49 -0700 Subject: libbpf: add ifindex to enable offload support BPF programs currently can only be offloaded using iproute2. This patch will allow programs to be offloaded using libbpf calls. Signed-off-by: David Beckett Reviewed-by: Jakub Kicinski Signed-off-by: Daniel Borkmann --- tools/lib/bpf/bpf.c | 2 ++ tools/lib/bpf/bpf.h | 2 ++ tools/lib/bpf/libbpf.c | 18 +++++++++++++++--- tools/lib/bpf/libbpf.h | 1 + 4 files changed, 20 insertions(+), 3 deletions(-) (limited to 'tools/lib/bpf/libbpf.c') diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index a3a8fb2ac697..6a8a00097fd8 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -91,6 +91,7 @@ int bpf_create_map_xattr(const struct bpf_create_map_attr *create_attr) attr.btf_fd = create_attr->btf_fd; attr.btf_key_id = create_attr->btf_key_id; attr.btf_value_id = create_attr->btf_value_id; + attr.map_ifindex = create_attr->map_ifindex; return sys_bpf(BPF_MAP_CREATE, &attr, sizeof(attr)); } @@ -201,6 +202,7 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr, attr.log_size = 0; attr.log_level = 0; attr.kern_version = load_attr->kern_version; + attr.prog_ifindex = load_attr->prog_ifindex; memcpy(attr.prog_name, load_attr->name, min(name_len, BPF_OBJ_NAME_LEN - 1)); diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h index fb3a146d92ff..15bff7728cf1 100644 --- a/tools/lib/bpf/bpf.h +++ b/tools/lib/bpf/bpf.h @@ -38,6 +38,7 @@ struct bpf_create_map_attr { __u32 btf_fd; __u32 btf_key_id; __u32 btf_value_id; + __u32 map_ifindex; }; int bpf_create_map_xattr(const struct bpf_create_map_attr *create_attr); @@ -64,6 +65,7 @@ struct bpf_load_program_attr { size_t insns_cnt; const char *license; __u32 kern_version; + __u32 prog_ifindex; }; /* Recommend log buffer size */ diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index df54c4c9e48a..3dbe217bf23e 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -178,6 +178,7 @@ struct bpf_program { /* Index in elf obj file, for relocation use. */ int idx; char *name; + int prog_ifindex; char *section_name; struct bpf_insn *insns; size_t insns_cnt, main_prog_cnt; @@ -213,6 +214,7 @@ struct bpf_map { int fd; char *name; size_t offset; + int map_ifindex; struct bpf_map_def def; uint32_t btf_key_id; uint32_t btf_value_id; @@ -1091,6 +1093,7 @@ bpf_object__create_maps(struct bpf_object *obj) int *pfd = &map->fd; create_attr.name = map->name; + create_attr.map_ifindex = map->map_ifindex; create_attr.map_type = def->type; create_attr.map_flags = def->map_flags; create_attr.key_size = def->key_size; @@ -1273,7 +1276,7 @@ static int bpf_object__collect_reloc(struct bpf_object *obj) static int load_program(enum bpf_prog_type type, enum bpf_attach_type expected_attach_type, const char *name, struct bpf_insn *insns, int insns_cnt, - char *license, u32 kern_version, int *pfd) + char *license, u32 kern_version, int *pfd, int prog_ifindex) { struct bpf_load_program_attr load_attr; char *log_buf; @@ -1287,6 +1290,7 @@ load_program(enum bpf_prog_type type, enum bpf_attach_type expected_attach_type, load_attr.insns_cnt = insns_cnt; load_attr.license = license; load_attr.kern_version = kern_version; + load_attr.prog_ifindex = prog_ifindex; if (!load_attr.insns || !load_attr.insns_cnt) return -EINVAL; @@ -1368,7 +1372,8 @@ bpf_program__load(struct bpf_program *prog, } err = load_program(prog->type, prog->expected_attach_type, prog->name, prog->insns, prog->insns_cnt, - license, kern_version, &fd); + license, kern_version, &fd, + prog->prog_ifindex); if (!err) prog->instances.fds[0] = fd; goto out; @@ -1399,7 +1404,8 @@ bpf_program__load(struct bpf_program *prog, err = load_program(prog->type, prog->expected_attach_type, prog->name, result.new_insn_ptr, result.new_insn_cnt, - license, kern_version, &fd); + license, kern_version, &fd, + prog->prog_ifindex); if (err) { pr_warning("Loading the %dth instance of program '%s' failed\n", @@ -2188,6 +2194,7 @@ int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, enum bpf_attach_type expected_attach_type; enum bpf_prog_type prog_type; struct bpf_object *obj; + struct bpf_map *map; int section_idx; int err; @@ -2207,6 +2214,7 @@ int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, * section name. */ prog_type = attr->prog_type; + prog->prog_ifindex = attr->ifindex; expected_attach_type = attr->expected_attach_type; if (prog_type == BPF_PROG_TYPE_UNSPEC) { section_idx = bpf_program__identify_section(prog); @@ -2227,6 +2235,10 @@ int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, first_prog = prog; } + bpf_map__for_each(map, obj) { + map->map_ifindex = attr->ifindex; + } + if (!first_prog) { pr_warning("object file doesn't contain bpf program\n"); bpf_object__close(obj); diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 4574b9563278..cd3fd8d782c7 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -259,6 +259,7 @@ struct bpf_prog_load_attr { const char *file; enum bpf_prog_type prog_type; enum bpf_attach_type expected_attach_type; + int ifindex; }; int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, -- cgit v1.2.3