1// SPDX-License-Identifier: GPL-2.0-or-later
  2#include <linux/objtool_types.h>
  3#include <asm/orc_types.h>
  4
  5#include <objtool/check.h>
  6#include <objtool/orc.h>
  7#include <objtool/warn.h>
  8#include <objtool/endianness.h>
  9
 10int init_orc_entry(struct orc_entry *orc, struct cfi_state *cfi, struct instruction *insn)
 11{
 12	struct cfi_reg *bp = &cfi->regs[CFI_BP];
 13
 14	memset(orc, 0, sizeof(*orc));
 15
 16	if (!cfi) {
 17		/*
 18		 * This is usually either unreachable nops/traps (which don't
 19		 * trigger unreachable instruction warnings), or
 20		 * STACK_FRAME_NON_STANDARD functions.
 21		 */
 22		orc->type = ORC_TYPE_UNDEFINED;
 23		return 0;
 24	}
 25
 26	switch (cfi->type) {
 27	case UNWIND_HINT_TYPE_UNDEFINED:
 28		orc->type = ORC_TYPE_UNDEFINED;
 29		return 0;
 30	case UNWIND_HINT_TYPE_END_OF_STACK:
 31		orc->type = ORC_TYPE_END_OF_STACK;
 32		return 0;
 33	case UNWIND_HINT_TYPE_CALL:
 34		orc->type = ORC_TYPE_CALL;
 35		break;
 36	case UNWIND_HINT_TYPE_REGS:
 37		orc->type = ORC_TYPE_REGS;
 38		break;
 39	case UNWIND_HINT_TYPE_REGS_PARTIAL:
 40		orc->type = ORC_TYPE_REGS_PARTIAL;
 41		break;
 42	default:
 43		WARN_INSN(insn, "unknown unwind hint type %d", cfi->type);
 44		return -1;
 45	}
 46
 47	orc->signal = cfi->signal;
 48
 49	switch (cfi->cfa.base) {
 50	case CFI_SP:
 51		orc->sp_reg = ORC_REG_SP;
 52		break;
 53	case CFI_SP_INDIRECT:
 54		orc->sp_reg = ORC_REG_SP_INDIRECT;
 55		break;
 56	case CFI_BP:
 57		orc->sp_reg = ORC_REG_BP;
 58		break;
 59	case CFI_BP_INDIRECT:
 60		orc->sp_reg = ORC_REG_BP_INDIRECT;
 61		break;
 62	case CFI_R10:
 63		orc->sp_reg = ORC_REG_R10;
 64		break;
 65	case CFI_R13:
 66		orc->sp_reg = ORC_REG_R13;
 67		break;
 68	case CFI_DI:
 69		orc->sp_reg = ORC_REG_DI;
 70		break;
 71	case CFI_DX:
 72		orc->sp_reg = ORC_REG_DX;
 73		break;
 74	default:
 75		WARN_INSN(insn, "unknown CFA base reg %d", cfi->cfa.base);
 76		return -1;
 77	}
 78
 79	switch (bp->base) {
 80	case CFI_UNDEFINED:
 81		orc->bp_reg = ORC_REG_UNDEFINED;
 82		break;
 83	case CFI_CFA:
 84		orc->bp_reg = ORC_REG_PREV_SP;
 85		break;
 86	case CFI_BP:
 87		orc->bp_reg = ORC_REG_BP;
 88		break;
 89	default:
 90		WARN_INSN(insn, "unknown BP base reg %d", bp->base);
 91		return -1;
 92	}
 93
 94	orc->sp_offset = cfi->cfa.offset;
 95	orc->bp_offset = bp->offset;
 96
 97	return 0;
 98}
 99
100int write_orc_entry(struct elf *elf, struct section *orc_sec,
101		    struct section *ip_sec, unsigned int idx,
102		    struct section *insn_sec, unsigned long insn_off,
103		    struct orc_entry *o)
104{
105	struct orc_entry *orc;
106
107	/* populate ORC data */
108	orc = (struct orc_entry *)orc_sec->data->d_buf + idx;
109	memcpy(orc, o, sizeof(*orc));
110	orc->sp_offset = bswap_if_needed(elf, orc->sp_offset);
111	orc->bp_offset = bswap_if_needed(elf, orc->bp_offset);
112
113	/* populate reloc for ip */
114	if (!elf_init_reloc_text_sym(elf, ip_sec, idx * sizeof(int), idx,
115				     insn_sec, insn_off))
116		return -1;
117
118	return 0;
119}
120
121static const char *reg_name(unsigned int reg)
122{
123	switch (reg) {
124	case ORC_REG_PREV_SP:
125		return "prevsp";
126	case ORC_REG_DX:
127		return "dx";
128	case ORC_REG_DI:
129		return "di";
130	case ORC_REG_BP:
131		return "bp";
132	case ORC_REG_SP:
133		return "sp";
134	case ORC_REG_R10:
135		return "r10";
136	case ORC_REG_R13:
137		return "r13";
138	case ORC_REG_BP_INDIRECT:
139		return "bp(ind)";
140	case ORC_REG_SP_INDIRECT:
141		return "sp(ind)";
142	default:
143		return "?";
144	}
145}
146
147static const char *orc_type_name(unsigned int type)
148{
149	switch (type) {
150	case ORC_TYPE_UNDEFINED:
151		return "(und)";
152	case ORC_TYPE_END_OF_STACK:
153		return "end";
154	case ORC_TYPE_CALL:
155		return "call";
156	case ORC_TYPE_REGS:
157		return "regs";
158	case ORC_TYPE_REGS_PARTIAL:
159		return "regs (partial)";
160	default:
161		return "?";
162	}
163}
164
165static void print_reg(unsigned int reg, int offset)
166{
167	if (reg == ORC_REG_BP_INDIRECT)
168		printf("(bp%+d)", offset);
169	else if (reg == ORC_REG_SP_INDIRECT)
170		printf("(sp)%+d", offset);
171	else if (reg == ORC_REG_UNDEFINED)
172		printf("(und)");
173	else
174		printf("%s%+d", reg_name(reg), offset);
175}
176
177void orc_print_dump(struct elf *dummy_elf, struct orc_entry *orc, int i)
178{
179	printf("type:%s", orc_type_name(orc[i].type));
180
181	printf(" sp:");
182	print_reg(orc[i].sp_reg, bswap_if_needed(dummy_elf, orc[i].sp_offset));
183
184	printf(" bp:");
185	print_reg(orc[i].bp_reg, bswap_if_needed(dummy_elf, orc[i].bp_offset));
186
187	printf(" signal:%d\n", orc[i].signal);
188}