1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Mapping of DWARF debug register numbers into register names. 4 * 5 * Copyright IBM Corp. 2010, 2017 6 * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com> 7 * 8 */ 9 10 #include <errno.h> 11 #include <stddef.h> 12 #include <stdlib.h> 13 #include <linux/kernel.h> 14 #include <asm/ptrace.h> 15 #include <string.h> 16 #include <dwarf-regs.h> 17 #include "dwarf-regs-table.h" 18 19 const char *get_arch_regstr(unsigned int n) 20 { 21 return (n >= ARRAY_SIZE(s390_dwarf_regs)) ? NULL : s390_dwarf_regs[n]; 22 } 23 24 /* 25 * Convert the register name into an offset to struct pt_regs (kernel). 26 * This is required by the BPF prologue generator. The BPF 27 * program is called in the BPF overflow handler in the perf 28 * core. 29 */ 30 int regs_query_register_offset(const char *name) 31 { 32 unsigned long gpr; 33 34 if (!name || strncmp(name, "%r", 2)) 35 return -EINVAL; 36 37 errno = 0; 38 gpr = strtoul(name + 2, NULL, 10); 39 if (errno || gpr >= 16) 40 return -EINVAL; 41 42 return offsetof(user_pt_regs, gprs) + 8 * gpr; 43 } 44