1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (c) 2022, Oracle and/or its affiliates. */ 3 #include "bpf_iter.h" 4 #include <bpf/bpf_helpers.h> 5 6 char _license[] SEC("license") = "GPL"; 7 8 unsigned long last_sym_value = 0; 9 10 static inline char to_lower(char c) 11 { 12 if (c >= 'A' && c <= 'Z') 13 c += ('a' - 'A'); 14 return c; 15 } 16 17 static inline char to_upper(char c) 18 { 19 if (c >= 'a' && c <= 'z') 20 c -= ('a' - 'A'); 21 return c; 22 } 23 24 /* Dump symbols with max size; the latter is calculated by caching symbol N value 25 * and when iterating on symbol N+1, we can print max size of symbol N via 26 * address of N+1 - address of N. 27 */ 28 SEC("iter/ksym") 29 int dump_ksym(struct bpf_iter__ksym *ctx) 30 { 31 struct seq_file *seq = ctx->meta->seq; 32 struct kallsym_iter *iter = ctx->ksym; 33 __u32 seq_num = ctx->meta->seq_num; 34 unsigned long value; 35 char type; 36 37 if (!iter) 38 return 0; 39 40 if (seq_num == 0) { 41 BPF_SEQ_PRINTF(seq, "ADDR TYPE NAME MODULE_NAME KIND MAX_SIZE\n"); 42 return 0; 43 } 44 if (last_sym_value) 45 BPF_SEQ_PRINTF(seq, "0x%x\n", iter->value - last_sym_value); 46 else 47 BPF_SEQ_PRINTF(seq, "\n"); 48 49 value = iter->show_value ? iter->value : 0; 50 51 last_sym_value = value; 52 53 type = iter->type; 54 55 if (iter->module_name[0]) { 56 type = iter->exported ? to_upper(type) : to_lower(type); 57 BPF_SEQ_PRINTF(seq, "0x%llx %c %s [ %s ] ", 58 value, type, iter->name, iter->module_name); 59 } else { 60 BPF_SEQ_PRINTF(seq, "0x%llx %c %s ", value, type, iter->name); 61 } 62 if (!iter->pos_mod_end || iter->pos_mod_end > iter->pos) 63 BPF_SEQ_PRINTF(seq, "MOD "); 64 else if (!iter->pos_ftrace_mod_end || iter->pos_ftrace_mod_end > iter->pos) 65 BPF_SEQ_PRINTF(seq, "FTRACE_MOD "); 66 else if (!iter->pos_bpf_end || iter->pos_bpf_end > iter->pos) 67 BPF_SEQ_PRINTF(seq, "BPF "); 68 else 69 BPF_SEQ_PRINTF(seq, "KPROBE "); 70 return 0; 71 } 72