[PATCH net-next V3 2/3] tools: bpftool: show filenames of pinned objects

@@ -45,6 +45,8 @@
 #include <sys/mount.h>
 #include <sys/types.h>
 #include <sys/vfs.h>
+#include <mntent.h>
+#include <fts.h>
 
 #include <bpf.h>
 

@@ -290,3 +292,86 @@ void print_hex_data_json(uint8_t *data, size_t len)
 		jsonw_printf(json_wtr, "\"0x%02hhx\"", data[i]);
 	jsonw_end_array(json_wtr);
 }
+
+int build_pinned_obj_table(struct pinned_obj_table *tab,
+			   enum bpf_obj_type type)
+{
+	struct bpf_prog_info pinned_info = {};
+	__u32 len = sizeof(pinned_info);
+	struct pinned_obj *obj_node = NULL;
+	enum bpf_obj_type objtype;
+	struct mntent *mntent = NULL;
+	FILE *mntfile = NULL;
+	FTSENT *ftse = NULL;
+	FTS *fts = NULL;
+	int fd, err;
+
+	mntfile = setmntent("/proc/mounts", "r");
+	if (!mntfile)
+		return -1;
+
+	while ((mntent = getmntent(mntfile)) != NULL) {
+		char *path[] = {mntent->mnt_dir, 0};
+
+		if (strncmp(mntent->mnt_type, "bpf", 3) != 0)
+			continue;
+
+		fts = fts_open(path, 0, NULL);
+		if (!fts)
+			continue;
+
+		while ((ftse = fts_read(fts)) != NULL) {
+			if (!(ftse->fts_info & FTS_F))
+				continue;
+			fd = open_obj_pinned(ftse->fts_path);
+			if (fd < 0)
+				continue;
+
+			objtype = get_fd_type(fd);
+			if (objtype != type) {
+				close(fd);
+				continue;
+			}
+			memset(&pinned_info, 0, sizeof(pinned_info));
+			err = bpf_obj_get_info_by_fd(fd, &pinned_info, &len);
+			if (err) {
+				close(fd);
+				continue;
+			}
+
+			obj_node = malloc(sizeof(*obj_node));
+			if (!obj_node) {
+				close(fd);
+				fts_close(fts);
+				fclose(mntfile);
+				return -1;
+			}
+
+			memset(obj_node, 0, sizeof(*obj_node));
+			obj_node->id = pinned_info.id;
+			obj_node->path = strdup(ftse->fts_path);
+			hash_add(tab->table, &obj_node->hash, obj_node->id);
+
+			close(fd);
+		}
+		fts_close(fts);
+	}
+	fclose(mntfile);
+	return 0;
+}
+
+void delete_pinned_obj_table(struct pinned_obj_table *tab)
+{
+	struct pinned_obj *obj;
+	struct hlist_node *tmp;
+	unsigned int bkt;
+
+	if (hash_empty(tab->table))
+		return;
+
+	hash_for_each_safe(tab->table, bkt, tmp, obj, hash) {
+		hash_del(&obj->hash);
+		free(obj->path);
+		free(obj);
+	}
+}

@@ -54,6 +54,8 @@ static int (*last_do_help)(int argc, char **argv);
 json_writer_t *json_wtr;
 bool pretty_output;
 bool json_output;
+struct pinned_obj_table prog_table;
+struct pinned_obj_table map_table;
 
 void usage(void)
 {

@@ -272,6 +274,9 @@ int main(int argc, char **argv)
 	json_output = false;
 	bin_name = argv[0];
 
+	hash_init(prog_table.table);
+	hash_init(map_table.table);
+
 	while ((opt = getopt_long(argc, argv, "Vhpj",
 				  options, NULL)) >= 0) {
 		switch (opt) {

@@ -311,5 +316,8 @@ int main(int argc, char **argv)
 	if (json_output)
 		jsonw_destroy(&json_wtr);
 
+	delete_pinned_obj_table(&prog_table);
+	delete_pinned_obj_table(&map_table);
+
 	return ret;
 }

@@ -42,6 +42,7 @@
 #include <stdio.h>
 #include <linux/bpf.h>
 #include <linux/kernel.h>
+#include <linux/hashtable.h>
 
 #include "json_writer.h"
 

@@ -70,11 +71,27 @@ extern const char *bin_name;
 
 extern json_writer_t *json_wtr;
 extern bool json_output;
+extern struct pinned_obj_table prog_table;
+extern struct pinned_obj_table map_table;
 
 bool is_prefix(const char *pfx, const char *str);
 void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep);
 void usage(void) __attribute__((noreturn));
 
+struct pinned_obj_table {
+	DECLARE_HASHTABLE(table, 16);
+};
+
+struct pinned_obj {
+	__u32 id;
+	char *path;
+	struct hlist_node hash;
+};
+
+int build_pinned_obj_table(struct pinned_obj_table *table,
+			   enum bpf_obj_type type);
+void delete_pinned_obj_table(struct pinned_obj_table *tab);
+
 struct cmd {
 	const char *cmd;
 	int (*func)(int argc, char **argv);

@@ -436,6 +436,18 @@ static int show_map_close_json(int fd, struct bpf_map_info *info)
 		jsonw_int_field(json_wtr, "bytes_memlock", atoi(memlock));
 	free(memlock);
 
+	if (!hash_empty(map_table.table)) {
+		struct pinned_obj *obj;
+
+		jsonw_name(json_wtr, "pinned");
+		jsonw_start_array(json_wtr);
+		hash_for_each_possible(map_table.table, obj, hash, info->id) {
+			if (obj->id == info->id)
+				jsonw_string(json_wtr, obj->path);
+		}
+		jsonw_end_array(json_wtr);
+	}
+
 	jsonw_end_object(json_wtr);
 
 	return 0;

@@ -466,7 +478,14 @@ static int show_map_close_plain(int fd, struct bpf_map_info *info)
 	free(memlock);
 
 	printf("\n");
+	if (!hash_empty(map_table.table)) {
+		struct pinned_obj *obj;
 
+		hash_for_each_possible(map_table.table, obj, hash, info->id) {
+			if (obj->id == info->id)
+				printf("\tpinned %s\n", obj->path);
+		}
+	}
 	return 0;
 }
 

@@ -478,6 +497,8 @@ static int do_show(int argc, char **argv)
 	int err;
 	int fd;
 
+	build_pinned_obj_table(&map_table, BPF_OBJ_MAP);
+
 	if (argc == 2) {
 		fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
 		if (fd < 0)

@@ -256,6 +256,18 @@ static void print_prog_json(struct bpf_prog_info *info, int fd)
 	if (info->nr_map_ids)
 		show_prog_maps(fd, info->nr_map_ids);
 
+	if (!hash_empty(prog_table.table)) {
+		struct pinned_obj *obj;
+
+		jsonw_name(json_wtr, "pinned");
+		jsonw_start_array(json_wtr);
+		hash_for_each_possible(prog_table.table, obj, hash, info->id) {
+			if (obj->id == info->id)
+				jsonw_string(json_wtr, obj->path);
+		}
+		jsonw_end_array(json_wtr);
+	}
+
 	jsonw_end_object(json_wtr);
 }
 

@@ -300,6 +312,16 @@ static void print_prog_plain(struct bpf_prog_info *info, int fd)
 	if (info->nr_map_ids)
 		show_prog_maps(fd, info->nr_map_ids);
 
+	if (!hash_empty(prog_table.table)) {
+		struct pinned_obj *obj;
+
+		printf("\n");
+		hash_for_each_possible(prog_table.table, obj, hash, info->id) {
+			if (obj->id == info->id)
+				printf("\tpinned %s\n", obj->path);
+		}
+	}
+
 	printf("\n");
 }
 

@@ -329,6 +351,8 @@ static int do_show(int argc, char **argv)
 	int err;
 	int fd;
 
+	build_pinned_obj_table(&prog_table, BPF_OBJ_PROG);
+
 	if (argc == 2) {
 		fd = prog_parse_fd(&argc, &argv);
 		if (fd < 0)