// SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ #include <vmlinux.h> #include <bpf/bpf_tracing.h> #include <bpf/bpf_helpers.h> #include <bpf/bpf_core_read.h> #include "../bpf_experimental.h" #include "../bpf_testmod/bpf_testmod_kfunc.h" struct node_data { long key; long data; struct bpf_rb_node node; }; struct plain_local { long key; long data; }; struct map_value { struct prog_test_ref_kfunc *not_kptr; struct prog_test_ref_kfunc __kptr *val; struct node_data __kptr *node; struct plain_local __kptr *plain; }; /* This is necessary so that LLVM generates BTF for node_data struct * If it's not included, a fwd reference for node_data will be generated but * no struct. Example BTF of "node" field in map_value when not included: * * [10] PTR '(anon)' type_id=35 * [34] FWD 'node_data' fwd_kind=struct * [35] TYPE_TAG 'kptr_ref' type_id=34 * * (with no node_data struct defined) * Had to do the same w/ bpf_kfunc_call_test_release below */ struct node_data *just_here_because_btf_bug; struct { __uint(type, BPF_MAP_TYPE_ARRAY); __type(key, int); __type(value, struct map_value); __uint(max_entries, 2); } some_nodes SEC(".maps"); static int create_and_stash(int idx, int val) { struct map_value *mapval; struct node_data *res; mapval = bpf_map_lookup_elem(&some_nodes, &idx); if (!mapval) return 1; res = bpf_obj_new(typeof(*res)); if (!res) return 1; res->key = val; res = bpf_kptr_xchg(&mapval->node, res); if (res) bpf_obj_drop(res); return 0; } SEC("tc") long stash_rb_nodes(void *ctx) { return create_and_stash(0, 41) ?: create_and_stash(1, 42); } SEC("tc") long stash_plain(void *ctx) { struct map_value *mapval; struct plain_local *res; int idx = 0; mapval = bpf_map_lookup_elem(&some_nodes, &idx); if (!mapval) return 1; res = bpf_obj_new(typeof(*res)); if (!res) return 1; res->key = 41; res = bpf_kptr_xchg(&mapval->plain, res); if (res) bpf_obj_drop(res); return 0; } SEC("tc") long unstash_rb_node(void *ctx) { struct map_value *mapval; struct node_data *res; long retval; int key = 1; mapval = bpf_map_lookup_elem(&some_nodes, &key); if (!mapval) return 1; res = bpf_kptr_xchg(&mapval->node, NULL); if (res) { retval = res->key; bpf_obj_drop(res); return retval; } return 1; } SEC("tc") long stash_test_ref_kfunc(void *ctx) { struct prog_test_ref_kfunc *res; struct map_value *mapval; int key = 0; mapval = bpf_map_lookup_elem(&some_nodes, &key); if (!mapval) return 1; res = bpf_kptr_xchg(&mapval->val, NULL); if (res) bpf_kfunc_call_test_release(res); return 0; } char _license[] SEC("license") = "GPL";