| 1 | // SPDX-License-Identifier: GPL-2.0 |
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| 2 | /* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ |
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| 3 | |
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| 4 | #include <vmlinux.h> |
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| 5 | #include <bpf/bpf_helpers.h> |
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| 6 | #include <bpf/bpf_tracing.h> |
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| 7 | #include <bpf/bpf_core_read.h> |
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| 8 | #include "../bpf_experimental.h" |
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| 9 | #include "bpf_misc.h" |
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| 10 | |
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| 11 | struct node_data { |
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| 12 | long key; |
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| 13 | long data; |
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| 14 | struct bpf_rb_node node; |
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| 15 | }; |
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| 16 | |
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| 17 | struct map_value { |
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| 18 | struct node_data __kptr *node; |
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| 19 | }; |
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| 20 | |
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| 21 | struct node_data2 { |
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| 22 | long key[4]; |
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| 23 | }; |
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| 24 | |
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| 25 | /* This is necessary so that LLVM generates BTF for node_data struct |
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| 26 | * If it's not included, a fwd reference for node_data will be generated but |
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| 27 | * no struct. Example BTF of "node" field in map_value when not included: |
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| 28 | * |
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| 29 | * [10] PTR '(anon)' type_id=35 |
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| 30 | * [34] FWD 'node_data' fwd_kind=struct |
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| 31 | * [35] TYPE_TAG 'kptr_ref' type_id=34 |
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| 32 | */ |
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| 33 | struct node_data *just_here_because_btf_bug; |
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| 34 | |
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| 35 | struct { |
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| 36 | __uint(type, BPF_MAP_TYPE_ARRAY); |
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| 37 | __type(key, int); |
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| 38 | __type(value, struct map_value); |
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| 39 | __uint(max_entries, 2); |
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| 40 | } some_nodes SEC(".maps" ); |
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| 41 | |
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| 42 | SEC("tc" ) |
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| 43 | __failure __msg("invalid kptr access, R2 type=ptr_node_data2 expected=ptr_node_data" ) |
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| 44 | long stash_rb_nodes(void *ctx) |
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| 45 | { |
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| 46 | struct map_value *mapval; |
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| 47 | struct node_data2 *res; |
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| 48 | int idx = 0; |
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| 49 | |
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| 50 | mapval = bpf_map_lookup_elem(&some_nodes, &idx); |
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| 51 | if (!mapval) |
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| 52 | return 1; |
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| 53 | |
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| 54 | res = bpf_obj_new(typeof(*res)); |
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| 55 | if (!res) |
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| 56 | return 1; |
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| 57 | res->key[0] = 40; |
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| 58 | |
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| 59 | res = bpf_kptr_xchg(&mapval->node, res); |
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| 60 | if (res) |
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| 61 | bpf_obj_drop(res); |
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| 62 | return 0; |
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| 63 | } |
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| 64 | |
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| 65 | SEC("tc" ) |
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| 66 | __failure __msg("R1 must have zero offset when passed to release func" ) |
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| 67 | long drop_rb_node_off(void *ctx) |
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| 68 | { |
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| 69 | struct map_value *mapval; |
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| 70 | struct node_data *res; |
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| 71 | int idx = 0; |
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| 72 | |
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| 73 | mapval = bpf_map_lookup_elem(&some_nodes, &idx); |
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| 74 | if (!mapval) |
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| 75 | return 1; |
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| 76 | |
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| 77 | res = bpf_obj_new(typeof(*res)); |
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| 78 | if (!res) |
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| 79 | return 1; |
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| 80 | /* Try releasing with graph node offset */ |
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| 81 | bpf_obj_drop(&res->node); |
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| 82 | return 0; |
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| 83 | } |
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| 84 | |
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| 85 | char _license[] SEC("license" ) = "GPL" ; |
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| 86 | |
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