1 files changed, 335 insertions, 24 deletions

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index d6e62e90e8d4..e827542ffa3a 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -124,6 +124,10 @@ struct bpf_program {
 	char *name;
 	int prog_ifindex;
 	char *section_name;
+	/* section_name with / replaced by _; makes recursive pinning
+	 * in bpf_object__pin_programs easier
+	 */
+	char *pin_name;
 	struct bpf_insn *insns;
 	size_t insns_cnt, main_prog_cnt;
 	enum bpf_prog_type type;
@@ -253,6 +257,7 @@ static void bpf_program__exit(struct bpf_program *prog)
 	bpf_program__unload(prog);
 	zfree(&prog->name);
 	zfree(&prog->section_name);
+	zfree(&prog->pin_name);
 	zfree(&prog->insns);
 	zfree(&prog->reloc_desc);
 
@@ -261,6 +266,17 @@ static void bpf_program__exit(struct bpf_program *prog)
 	prog->idx = -1;
 }
 
+static char *__bpf_program__pin_name(struct bpf_program *prog)
+{
+	char *name, *p;
+
+	name = p = strdup(prog->section_name);
+	while ((p = strchr(p, '/')))
+		*p = '_';
+
+	return name;
+}
+
 static int
 bpf_program__init(void *data, size_t size, char *section_name, int idx,
 		  struct bpf_program *prog)
@@ -279,6 +295,13 @@ bpf_program__init(void *data, size_t size, char *section_name, int idx,
 		goto errout;
 	}
 
+	prog->pin_name = __bpf_program__pin_name(prog);
+	if (!prog->pin_name) {
+		pr_warning("failed to alloc pin name for prog under section(%d) %s\n",
+			   idx, section_name);
+		goto errout;
+	}
+
 	prog->insns = malloc(size);
 	if (!prog->insns) {
 		pr_warning("failed to alloc insns for prog under section %s\n",
@@ -1699,6 +1722,34 @@ int bpf_program__pin_instance(struct bpf_program *prog, const char *path,
 	return 0;
 }
 
+int bpf_program__unpin_instance(struct bpf_program *prog, const char *path,
+				int instance)
+{
+	int err;
+
+	err = check_path(path);
+	if (err)
+		return err;
+
+	if (prog == NULL) {
+		pr_warning("invalid program pointer\n");
+		return -EINVAL;
+	}
+
+	if (instance < 0 || instance >= prog->instances.nr) {
+		pr_warning("invalid prog instance %d of prog %s (max %d)\n",
+			   instance, prog->section_name, prog->instances.nr);
+		return -EINVAL;
+	}
+
+	err = unlink(path);
+	if (err != 0)
+		return -errno;
+	pr_debug("unpinned program '%s'\n", path);
+
+	return 0;
+}
+
 static int make_dir(const char *path)
 {
 	char *cp, errmsg[STRERR_BUFSIZE];
@@ -1733,6 +1784,11 @@ int bpf_program__pin(struct bpf_program *prog, const char *path)
 		return -EINVAL;
 	}
 
+	if (prog->instances.nr == 1) {
+		/* don't create subdirs when pinning single instance */
+		return bpf_program__pin_instance(prog, path, 0);
+	}
+
 	err = make_dir(path);
 	if (err)
 		return err;
@@ -1742,16 +1798,83 @@ int bpf_program__pin(struct bpf_program *prog, const char *path)
 		int len;
 
 		len = snprintf(buf, PATH_MAX, "%s/%d", path, i);
+		if (len < 0) {
+			err = -EINVAL;
+			goto err_unpin;
+		} else if (len >= PATH_MAX) {
+			err = -ENAMETOOLONG;
+			goto err_unpin;
+		}
+
+		err = bpf_program__pin_instance(prog, buf, i);
+		if (err)
+			goto err_unpin;
+	}
+
+	return 0;
+
+err_unpin:
+	for (i = i - 1; i >= 0; i--) {
+		char buf[PATH_MAX];
+		int len;
+
+		len = snprintf(buf, PATH_MAX, "%s/%d", path, i);
+		if (len < 0)
+			continue;
+		else if (len >= PATH_MAX)
+			continue;
+
+		bpf_program__unpin_instance(prog, buf, i);
+	}
+
+	rmdir(path);
+
+	return err;
+}
+
+int bpf_program__unpin(struct bpf_program *prog, const char *path)
+{
+	int i, err;
+
+	err = check_path(path);
+	if (err)
+		return err;
+
+	if (prog == NULL) {
+		pr_warning("invalid program pointer\n");
+		return -EINVAL;
+	}
+
+	if (prog->instances.nr <= 0) {
+		pr_warning("no instances of prog %s to pin\n",
+			   prog->section_name);
+		return -EINVAL;
+	}
+
+	if (prog->instances.nr == 1) {
+		/* don't create subdirs when pinning single instance */
+		return bpf_program__unpin_instance(prog, path, 0);
+	}
+
+	for (i = 0; i < prog->instances.nr; i++) {
+		char buf[PATH_MAX];
+		int len;
+
+		len = snprintf(buf, PATH_MAX, "%s/%d", path, i);
 		if (len < 0)
 			return -EINVAL;
 		else if (len >= PATH_MAX)
 			return -ENAMETOOLONG;
 
-		err = bpf_program__pin_instance(prog, buf, i);
+		err = bpf_program__unpin_instance(prog, buf, i);
 		if (err)
 			return err;
 	}
 
+	err = rmdir(path);
+	if (err)
+		return -errno;
+
 	return 0;
 }
 
@@ -1776,12 +1899,33 @@ int bpf_map__pin(struct bpf_map *map, const char *path)
 	}
 
 	pr_debug("pinned map '%s'\n", path);
+
 	return 0;
 }
 
-int bpf_object__pin(struct bpf_object *obj, const char *path)
+int bpf_map__unpin(struct bpf_map *map, const char *path)
+{
+	int err;
+
+	err = check_path(path);
+	if (err)
+		return err;
+
+	if (map == NULL) {
+		pr_warning("invalid map pointer\n");
+		return -EINVAL;
+	}
+
+	err = unlink(path);
+	if (err != 0)
+		return -errno;
+	pr_debug("unpinned map '%s'\n", path);
+
+	return 0;
+}
+
+int bpf_object__pin_maps(struct bpf_object *obj, const char *path)
 {
-	struct bpf_program *prog;
 	struct bpf_map *map;
 	int err;
 
@@ -1803,28 +1947,142 @@ int bpf_object__pin(struct bpf_object *obj, const char *path)
 
 		len = snprintf(buf, PATH_MAX, "%s/%s", path,
 			       bpf_map__name(map));
+		if (len < 0) {
+			err = -EINVAL;
+			goto err_unpin_maps;
+		} else if (len >= PATH_MAX) {
+			err = -ENAMETOOLONG;
+			goto err_unpin_maps;
+		}
+
+		err = bpf_map__pin(map, buf);
+		if (err)
+			goto err_unpin_maps;
+	}
+
+	return 0;
+
+err_unpin_maps:
+	while ((map = bpf_map__prev(map, obj))) {
+		char buf[PATH_MAX];
+		int len;
+
+		len = snprintf(buf, PATH_MAX, "%s/%s", path,
+			       bpf_map__name(map));
+		if (len < 0)
+			continue;
+		else if (len >= PATH_MAX)
+			continue;
+
+		bpf_map__unpin(map, buf);
+	}
+
+	return err;
+}
+
+int bpf_object__unpin_maps(struct bpf_object *obj, const char *path)
+{
+	struct bpf_map *map;
+	int err;
+
+	if (!obj)
+		return -ENOENT;
+
+	bpf_map__for_each(map, obj) {
+		char buf[PATH_MAX];
+		int len;
+
+		len = snprintf(buf, PATH_MAX, "%s/%s", path,
+			       bpf_map__name(map));
 		if (len < 0)
 			return -EINVAL;
 		else if (len >= PATH_MAX)
 			return -ENAMETOOLONG;
 
-		err = bpf_map__pin(map, buf);
+		err = bpf_map__unpin(map, buf);
 		if (err)
 			return err;
 	}
 
+	return 0;
+}
+
+int bpf_object__pin_programs(struct bpf_object *obj, const char *path)
+{
+	struct bpf_program *prog;
+	int err;
+
+	if (!obj)
+		return -ENOENT;
+
+	if (!obj->loaded) {
+		pr_warning("object not yet loaded; load it first\n");
+		return -ENOENT;
+	}
+
+	err = make_dir(path);
+	if (err)
+		return err;
+
 	bpf_object__for_each_program(prog, obj) {
 		char buf[PATH_MAX];
 		int len;
 
 		len = snprintf(buf, PATH_MAX, "%s/%s", path,
-			       prog->section_name);
+			       prog->pin_name);
+		if (len < 0) {
+			err = -EINVAL;
+			goto err_unpin_programs;
+		} else if (len >= PATH_MAX) {
+			err = -ENAMETOOLONG;
+			goto err_unpin_programs;
+		}
+
+		err = bpf_program__pin(prog, buf);
+		if (err)
+			goto err_unpin_programs;
+	}
+
+	return 0;
+
+err_unpin_programs:
+	while ((prog = bpf_program__prev(prog, obj))) {
+		char buf[PATH_MAX];
+		int len;
+
+		len = snprintf(buf, PATH_MAX, "%s/%s", path,
+			       prog->pin_name);
+		if (len < 0)
+			continue;
+		else if (len >= PATH_MAX)
+			continue;
+
+		bpf_program__unpin(prog, buf);
+	}
+
+	return err;
+}
+
+int bpf_object__unpin_programs(struct bpf_object *obj, const char *path)
+{
+	struct bpf_program *prog;
+	int err;
+
+	if (!obj)
+		return -ENOENT;
+
+	bpf_object__for_each_program(prog, obj) {
+		char buf[PATH_MAX];
+		int len;
+
+		len = snprintf(buf, PATH_MAX, "%s/%s", path,
+			       prog->pin_name);
 		if (len < 0)
 			return -EINVAL;
 		else if (len >= PATH_MAX)
 			return -ENAMETOOLONG;
 
-		err = bpf_program__pin(prog, buf);
+		err = bpf_program__unpin(prog, buf);
 		if (err)
 			return err;
 	}
@@ -1832,6 +2090,23 @@ int bpf_object__pin(struct bpf_object *obj, const char *path)
 	return 0;
 }
 
+int bpf_object__pin(struct bpf_object *obj, const char *path)
+{
+	int err;
+
+	err = bpf_object__pin_maps(obj, path);
+	if (err)
+		return err;
+
+	err = bpf_object__pin_programs(obj, path);
+	if (err) {
+		bpf_object__unpin_maps(obj, path);
+		return err;
+	}
+
+	return 0;
+}
+
 void bpf_object__close(struct bpf_object *obj)
 {
 	size_t i;
@@ -1918,23 +2193,20 @@ void *bpf_object__priv(struct bpf_object *obj)
 }
 
 static struct bpf_program *
-__bpf_program__next(struct bpf_program *prev, struct bpf_object *obj)
+__bpf_program__iter(struct bpf_program *p, struct bpf_object *obj, int i)
 {
-	size_t idx;
+	ssize_t idx;
 
 	if (!obj->programs)
 		return NULL;
-	/* First handler */
-	if (prev == NULL)
-		return &obj->programs[0];
 
-	if (prev->obj != obj) {
+	if (p->obj != obj) {
 		pr_warning("error: program handler doesn't match object\n");
 		return NULL;
 	}
 
-	idx = (prev - obj->programs) + 1;
-	if (idx >= obj->nr_programs)
+	idx = (p - obj->programs) + i;
+	if (idx >= obj->nr_programs || idx < 0)
 		return NULL;
 	return &obj->programs[idx];
 }
@@ -1944,8 +2216,29 @@ bpf_program__next(struct bpf_program *prev, struct bpf_object *obj)
 {
 	struct bpf_program *prog = prev;
 
+	if (prev == NULL)
+		return obj->programs;
+
 	do {
-		prog = __bpf_program__next(prog, obj);
+		prog = __bpf_program__iter(prog, obj, 1);
+	} while (prog && bpf_program__is_function_storage(prog, obj));
+
+	return prog;
+}
+
+struct bpf_program *
+bpf_program__prev(struct bpf_program *next, struct bpf_object *obj)
+{
+	struct bpf_program *prog = next;
+
+	if (next == NULL) {
+		if (!obj->nr_programs)
+			return NULL;
+		return obj->programs + obj->nr_programs - 1;
+	}
+
+	do {
+		prog = __bpf_program__iter(prog, obj, -1);
 	} while (prog && bpf_program__is_function_storage(prog, obj));
 
 	return prog;
@@ -2272,10 +2565,10 @@ void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex)
 	map->map_ifindex = ifindex;
 }
 
-struct bpf_map *
-bpf_map__next(struct bpf_map *prev, struct bpf_object *obj)
+static struct bpf_map *
+__bpf_map__iter(struct bpf_map *m, struct bpf_object *obj, int i)
 {
-	size_t idx;
+	ssize_t idx;
 	struct bpf_map *s, *e;
 
 	if (!obj || !obj->maps)
@@ -2284,22 +2577,40 @@ bpf_map__next(struct bpf_map *prev, struct bpf_object *obj)
 	s = obj->maps;
 	e = obj->maps + obj->nr_maps;
 
-	if (prev == NULL)
-		return s;
-
-	if ((prev < s) || (prev >= e)) {
+	if ((m < s) || (m >= e)) {
 		pr_warning("error in %s: map handler doesn't belong to object\n",
 			   __func__);
 		return NULL;
 	}
 
-	idx = (prev - obj->maps) + 1;
-	if (idx >= obj->nr_maps)
+	idx = (m - obj->maps) + i;
+	if (idx >= obj->nr_maps || idx < 0)
 		return NULL;
 	return &obj->maps[idx];
 }
 
 struct bpf_map *
+bpf_map__next(struct bpf_map *prev, struct bpf_object *obj)
+{
+	if (prev == NULL)
+		return obj->maps;
+
+	return __bpf_map__iter(prev, obj, 1);
+}
+
+struct bpf_map *
+bpf_map__prev(struct bpf_map *next, struct bpf_object *obj)
+{
+	if (next == NULL) {
+		if (!obj->nr_maps)
+			return NULL;
+		return obj->maps + obj->nr_maps - 1;
+	}
+
+	return __bpf_map__iter(next, obj, -1);
+}
+
+struct bpf_map *
 bpf_object__find_map_by_name(struct bpf_object *obj, const char *name)
 {
 	struct bpf_map *pos;