1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (c) 2020 Facebook */ 3 #define bpf_iter_meta bpf_iter_meta___not_used 4 #define bpf_iter__bpf_map bpf_iter__bpf_map___not_used 5 #include "vmlinux.h" 6 #undef bpf_iter_meta 7 #undef bpf_iter__bpf_map 8 #include <bpf/bpf_helpers.h> 9 10 char _license[] SEC("license") = "GPL"; 11 12 struct bpf_iter_meta { 13 struct seq_file *seq; 14 __u64 session_id; 15 __u64 seq_num; 16 } __attribute__((preserve_access_index)); 17 18 struct bpf_iter__bpf_map { 19 struct bpf_iter_meta *meta; 20 struct bpf_map *map; 21 } __attribute__((preserve_access_index)); 22 23 __u32 map1_id = 0, map2_id = 0; 24 __u32 map1_accessed = 0, map2_accessed = 0; 25 __u64 map1_seqnum = 0, map2_seqnum1 = 0, map2_seqnum2 = 0; 26 27 static volatile const __u32 print_len; 28 static volatile const __u32 ret1; 29 30 SEC("iter/bpf_map") 31 int dump_bpf_map(struct bpf_iter__bpf_map *ctx) 32 { 33 struct seq_file *seq = ctx->meta->seq; 34 struct bpf_map *map = ctx->map; 35 __u64 seq_num; 36 int i, ret = 0; 37 38 if (map == (void *)0) 39 return 0; 40 41 /* only dump map1_id and map2_id */ 42 if (map->id != map1_id && map->id != map2_id) 43 return 0; 44 45 seq_num = ctx->meta->seq_num; 46 if (map->id == map1_id) { 47 map1_seqnum = seq_num; 48 map1_accessed++; 49 } 50 51 if (map->id == map2_id) { 52 if (map2_accessed == 0) { 53 map2_seqnum1 = seq_num; 54 if (ret1) 55 ret = 1; 56 } else { 57 map2_seqnum2 = seq_num; 58 } 59 map2_accessed++; 60 } 61 62 /* fill seq_file buffer */ 63 for (i = 0; i < print_len; i++) 64 bpf_seq_write(seq, &seq_num, sizeof(seq_num)); 65 66 return ret; 67 } 68