diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/local_kptr_stash.c')
-rw-r--r-- | tools/testing/selftests/bpf/progs/local_kptr_stash.c | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/local_kptr_stash.c b/tools/testing/selftests/bpf/progs/local_kptr_stash.c new file mode 100644 index 000000000000..0ef286da092b --- /dev/null +++ b/tools/testing/selftests/bpf/progs/local_kptr_stash.c @@ -0,0 +1,108 @@ +// 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" + +struct node_data { + long key; + long data; + struct bpf_rb_node node; +}; + +struct map_value { + struct prog_test_ref_kfunc *not_kptr; + struct prog_test_ref_kfunc __kptr *val; + struct node_data __kptr *node; +}; + +/* 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; + +extern void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym; + +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 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"; |