diff options
Diffstat (limited to 'tools/objtool/arch/loongarch')
| -rw-r--r-- | tools/objtool/arch/loongarch/Build | 3 | ||||
| -rw-r--r-- | tools/objtool/arch/loongarch/decode.c | 389 | ||||
| -rw-r--r-- | tools/objtool/arch/loongarch/include/arch/cfi_regs.h | 22 | ||||
| -rw-r--r-- | tools/objtool/arch/loongarch/include/arch/elf.h | 37 | ||||
| -rw-r--r-- | tools/objtool/arch/loongarch/include/arch/special.h | 33 | ||||
| -rw-r--r-- | tools/objtool/arch/loongarch/orc.c | 171 | ||||
| -rw-r--r-- | tools/objtool/arch/loongarch/special.c | 173 |
7 files changed, 828 insertions, 0 deletions
diff --git a/tools/objtool/arch/loongarch/Build b/tools/objtool/arch/loongarch/Build new file mode 100644 index 000000000000..1d4b784b6887 --- /dev/null +++ b/tools/objtool/arch/loongarch/Build @@ -0,0 +1,3 @@ +objtool-y += decode.o +objtool-y += special.o +objtool-y += orc.o diff --git a/tools/objtool/arch/loongarch/decode.c b/tools/objtool/arch/loongarch/decode.c new file mode 100644 index 000000000000..b6fdc68053cc --- /dev/null +++ b/tools/objtool/arch/loongarch/decode.c @@ -0,0 +1,389 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +#include <string.h> +#include <objtool/check.h> +#include <objtool/warn.h> +#include <asm/inst.h> +#include <asm/orc_types.h> +#include <linux/objtool_types.h> +#include <arch/elf.h> + +int arch_ftrace_match(char *name) +{ + return !strcmp(name, "_mcount"); +} + +unsigned long arch_jump_destination(struct instruction *insn) +{ + return insn->offset + (insn->immediate << 2); +} + +unsigned long arch_dest_reloc_offset(int addend) +{ + return addend; +} + +bool arch_pc_relative_reloc(struct reloc *reloc) +{ + return false; +} + +bool arch_callee_saved_reg(unsigned char reg) +{ + switch (reg) { + case CFI_RA: + case CFI_FP: + case CFI_S0 ... CFI_S8: + return true; + default: + return false; + } +} + +int arch_decode_hint_reg(u8 sp_reg, int *base) +{ + switch (sp_reg) { + case ORC_REG_UNDEFINED: + *base = CFI_UNDEFINED; + break; + case ORC_REG_SP: + *base = CFI_SP; + break; + case ORC_REG_FP: + *base = CFI_FP; + break; + default: + return -1; + } + + return 0; +} + +static bool is_loongarch(const struct elf *elf) +{ + if (elf->ehdr.e_machine == EM_LOONGARCH) + return true; + + ERROR("unexpected ELF machine type %d", elf->ehdr.e_machine); + return false; +} + +#define ADD_OP(op) \ + if (!(op = calloc(1, sizeof(*op)))) \ + return -1; \ + else for (*ops_list = op, ops_list = &op->next; op; op = NULL) + +static bool decode_insn_reg0i26_fomat(union loongarch_instruction inst, + struct instruction *insn) +{ + switch (inst.reg0i26_format.opcode) { + case b_op: + insn->type = INSN_JUMP_UNCONDITIONAL; + insn->immediate = sign_extend64(inst.reg0i26_format.immediate_h << 16 | + inst.reg0i26_format.immediate_l, 25); + break; + case bl_op: + insn->type = INSN_CALL; + insn->immediate = sign_extend64(inst.reg0i26_format.immediate_h << 16 | + inst.reg0i26_format.immediate_l, 25); + break; + default: + return false; + } + + return true; +} + +static bool decode_insn_reg1i21_fomat(union loongarch_instruction inst, + struct instruction *insn) +{ + switch (inst.reg1i21_format.opcode) { + case beqz_op: + case bnez_op: + case bceqz_op: + insn->type = INSN_JUMP_CONDITIONAL; + insn->immediate = sign_extend64(inst.reg1i21_format.immediate_h << 16 | + inst.reg1i21_format.immediate_l, 20); + break; + default: + return false; + } + + return true; +} + +static bool decode_insn_reg2i12_fomat(union loongarch_instruction inst, + struct instruction *insn, + struct stack_op **ops_list, + struct stack_op *op) +{ + switch (inst.reg2i12_format.opcode) { + case addid_op: + if ((inst.reg2i12_format.rd == CFI_SP) || (inst.reg2i12_format.rj == CFI_SP)) { + /* addi.d sp,sp,si12 or addi.d fp,sp,si12 or addi.d sp,fp,si12 */ + insn->immediate = sign_extend64(inst.reg2i12_format.immediate, 11); + ADD_OP(op) { + op->src.type = OP_SRC_ADD; + op->src.reg = inst.reg2i12_format.rj; + op->src.offset = insn->immediate; + op->dest.type = OP_DEST_REG; + op->dest.reg = inst.reg2i12_format.rd; + } + } + if ((inst.reg2i12_format.rd == CFI_SP) && (inst.reg2i12_format.rj == CFI_FP)) { + /* addi.d sp,fp,si12 */ + struct symbol *func = find_func_containing(insn->sec, insn->offset); + + if (!func) + return false; + + func->frame_pointer = true; + } + break; + case ldd_op: + if (inst.reg2i12_format.rj == CFI_SP) { + /* ld.d rd,sp,si12 */ + insn->immediate = sign_extend64(inst.reg2i12_format.immediate, 11); + ADD_OP(op) { + op->src.type = OP_SRC_REG_INDIRECT; + op->src.reg = CFI_SP; + op->src.offset = insn->immediate; + op->dest.type = OP_DEST_REG; + op->dest.reg = inst.reg2i12_format.rd; + } + } + break; + case std_op: + if (inst.reg2i12_format.rj == CFI_SP) { + /* st.d rd,sp,si12 */ + insn->immediate = sign_extend64(inst.reg2i12_format.immediate, 11); + ADD_OP(op) { + op->src.type = OP_SRC_REG; + op->src.reg = inst.reg2i12_format.rd; + op->dest.type = OP_DEST_REG_INDIRECT; + op->dest.reg = CFI_SP; + op->dest.offset = insn->immediate; + } + } + break; + case andi_op: + if (inst.reg2i12_format.rd == 0 && + inst.reg2i12_format.rj == 0 && + inst.reg2i12_format.immediate == 0) + /* andi r0,r0,0 */ + insn->type = INSN_NOP; + break; + default: + return false; + } + + return true; +} + +static bool decode_insn_reg2i14_fomat(union loongarch_instruction inst, + struct instruction *insn, + struct stack_op **ops_list, + struct stack_op *op) +{ + switch (inst.reg2i14_format.opcode) { + case ldptrd_op: + if (inst.reg2i14_format.rj == CFI_SP) { + /* ldptr.d rd,sp,si14 */ + insn->immediate = sign_extend64(inst.reg2i14_format.immediate, 13); + ADD_OP(op) { + op->src.type = OP_SRC_REG_INDIRECT; + op->src.reg = CFI_SP; + op->src.offset = insn->immediate; + op->dest.type = OP_DEST_REG; + op->dest.reg = inst.reg2i14_format.rd; + } + } + break; + case stptrd_op: + if (inst.reg2i14_format.rj == CFI_SP) { + /* stptr.d ra,sp,0 */ + if (inst.reg2i14_format.rd == LOONGARCH_GPR_RA && + inst.reg2i14_format.immediate == 0) + break; + + /* stptr.d rd,sp,si14 */ + insn->immediate = sign_extend64(inst.reg2i14_format.immediate, 13); + ADD_OP(op) { + op->src.type = OP_SRC_REG; + op->src.reg = inst.reg2i14_format.rd; + op->dest.type = OP_DEST_REG_INDIRECT; + op->dest.reg = CFI_SP; + op->dest.offset = insn->immediate; + } + } + break; + default: + return false; + } + + return true; +} + +static bool decode_insn_reg2i16_fomat(union loongarch_instruction inst, + struct instruction *insn) +{ + switch (inst.reg2i16_format.opcode) { + case jirl_op: + if (inst.reg2i16_format.rd == 0 && + inst.reg2i16_format.rj == CFI_RA && + inst.reg2i16_format.immediate == 0) { + /* jirl r0,ra,0 */ + insn->type = INSN_RETURN; + } else if (inst.reg2i16_format.rd == CFI_RA) { + /* jirl ra,rj,offs16 */ + insn->type = INSN_CALL_DYNAMIC; + } else if (inst.reg2i16_format.rd == CFI_A0 && + inst.reg2i16_format.immediate == 0) { + /* + * jirl a0,t0,0 + * this is a special case in loongarch_suspend_enter, + * just treat it as a call instruction. + */ + insn->type = INSN_CALL_DYNAMIC; + } else if (inst.reg2i16_format.rd == 0 && + inst.reg2i16_format.immediate == 0) { + /* jirl r0,rj,0 */ + insn->type = INSN_JUMP_DYNAMIC; + } else if (inst.reg2i16_format.rd == 0 && + inst.reg2i16_format.immediate != 0) { + /* + * jirl r0,t0,12 + * this is a rare case in JUMP_VIRT_ADDR, + * just ignore it due to it is harmless for tracing. + */ + break; + } else { + /* jirl rd,rj,offs16 */ + insn->type = INSN_JUMP_UNCONDITIONAL; + insn->immediate = sign_extend64(inst.reg2i16_format.immediate, 15); + } + break; + case beq_op: + case bne_op: + case blt_op: + case bge_op: + case bltu_op: + case bgeu_op: + insn->type = INSN_JUMP_CONDITIONAL; + insn->immediate = sign_extend64(inst.reg2i16_format.immediate, 15); + break; + default: + return false; + } + + return true; +} + +int arch_decode_instruction(struct objtool_file *file, const struct section *sec, + unsigned long offset, unsigned int maxlen, + struct instruction *insn) +{ + struct stack_op **ops_list = &insn->stack_ops; + const struct elf *elf = file->elf; + struct stack_op *op = NULL; + union loongarch_instruction inst; + + if (!is_loongarch(elf)) + return -1; + + if (maxlen < LOONGARCH_INSN_SIZE) + return 0; + + insn->len = LOONGARCH_INSN_SIZE; + insn->type = INSN_OTHER; + insn->immediate = 0; + + inst = *(union loongarch_instruction *)(sec->data->d_buf + offset); + + if (decode_insn_reg0i26_fomat(inst, insn)) + return 0; + if (decode_insn_reg1i21_fomat(inst, insn)) + return 0; + if (decode_insn_reg2i12_fomat(inst, insn, ops_list, op)) + return 0; + if (decode_insn_reg2i14_fomat(inst, insn, ops_list, op)) + return 0; + if (decode_insn_reg2i16_fomat(inst, insn)) + return 0; + + if (inst.word == 0) + insn->type = INSN_NOP; + else if (inst.reg0i15_format.opcode == break_op) { + /* break */ + insn->type = INSN_BUG; + } else if (inst.reg2_format.opcode == ertn_op) { + /* ertn */ + insn->type = INSN_RETURN; + } + + return 0; +} + +const char *arch_nop_insn(int len) +{ + static u32 nop; + + if (len != LOONGARCH_INSN_SIZE) { + ERROR("invalid NOP size: %d\n", len); + return NULL; + } + + nop = LOONGARCH_INSN_NOP; + + return (const char *)&nop; +} + +const char *arch_ret_insn(int len) +{ + static u32 ret; + + if (len != LOONGARCH_INSN_SIZE) { + ERROR("invalid RET size: %d\n", len); + return NULL; + } + + emit_jirl((union loongarch_instruction *)&ret, LOONGARCH_GPR_RA, LOONGARCH_GPR_ZERO, 0); + + return (const char *)&ret; +} + +void arch_initial_func_cfi_state(struct cfi_init_state *state) +{ + int i; + + for (i = 0; i < CFI_NUM_REGS; i++) { + state->regs[i].base = CFI_UNDEFINED; + state->regs[i].offset = 0; + } + + /* initial CFA (call frame address) */ + state->cfa.base = CFI_SP; + state->cfa.offset = 0; +} + +unsigned int arch_reloc_size(struct reloc *reloc) +{ + switch (reloc_type(reloc)) { + case R_LARCH_32: + case R_LARCH_32_PCREL: + return 4; + default: + return 8; + } +} + +unsigned long arch_jump_table_sym_offset(struct reloc *reloc, struct reloc *table) +{ + switch (reloc_type(reloc)) { + case R_LARCH_32_PCREL: + case R_LARCH_64_PCREL: + return reloc->sym->offset + reloc_addend(reloc) - + (reloc_offset(reloc) - reloc_offset(table)); + default: + return reloc->sym->offset + reloc_addend(reloc); + } +} diff --git a/tools/objtool/arch/loongarch/include/arch/cfi_regs.h b/tools/objtool/arch/loongarch/include/arch/cfi_regs.h new file mode 100644 index 000000000000..d183cc8f43bf --- /dev/null +++ b/tools/objtool/arch/loongarch/include/arch/cfi_regs.h @@ -0,0 +1,22 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef _OBJTOOL_ARCH_CFI_REGS_H +#define _OBJTOOL_ARCH_CFI_REGS_H + +#define CFI_RA 1 +#define CFI_SP 3 +#define CFI_A0 4 +#define CFI_FP 22 +#define CFI_S0 23 +#define CFI_S1 24 +#define CFI_S2 25 +#define CFI_S3 26 +#define CFI_S4 27 +#define CFI_S5 28 +#define CFI_S6 29 +#define CFI_S7 30 +#define CFI_S8 31 +#define CFI_NUM_REGS 32 + +#define CFI_BP CFI_FP + +#endif /* _OBJTOOL_ARCH_CFI_REGS_H */ diff --git a/tools/objtool/arch/loongarch/include/arch/elf.h b/tools/objtool/arch/loongarch/include/arch/elf.h new file mode 100644 index 000000000000..ec79062c9554 --- /dev/null +++ b/tools/objtool/arch/loongarch/include/arch/elf.h @@ -0,0 +1,37 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef _OBJTOOL_ARCH_ELF_H +#define _OBJTOOL_ARCH_ELF_H + +/* + * See the following link for more info about ELF Relocation types: + * https://loongson.github.io/LoongArch-Documentation/LoongArch-ELF-ABI-EN.html#_relocations + */ +#ifndef R_LARCH_NONE +#define R_LARCH_NONE 0 +#endif +#ifndef R_LARCH_32 +#define R_LARCH_32 1 +#endif +#ifndef R_LARCH_64 +#define R_LARCH_64 2 +#endif +#ifndef R_LARCH_32_PCREL +#define R_LARCH_32_PCREL 99 +#endif +#ifndef R_LARCH_64_PCREL +#define R_LARCH_64_PCREL 109 +#endif + +#ifndef EM_LOONGARCH +#define EM_LOONGARCH 258 +#endif + +#define R_NONE R_LARCH_NONE +#define R_ABS32 R_LARCH_32 +#define R_ABS64 R_LARCH_64 +#define R_DATA32 R_LARCH_32_PCREL +#define R_DATA64 R_LARCH_32_PCREL +#define R_TEXT32 R_LARCH_32_PCREL +#define R_TEXT64 R_LARCH_32_PCREL + +#endif /* _OBJTOOL_ARCH_ELF_H */ diff --git a/tools/objtool/arch/loongarch/include/arch/special.h b/tools/objtool/arch/loongarch/include/arch/special.h new file mode 100644 index 000000000000..35fc979b550a --- /dev/null +++ b/tools/objtool/arch/loongarch/include/arch/special.h @@ -0,0 +1,33 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef _OBJTOOL_ARCH_SPECIAL_H +#define _OBJTOOL_ARCH_SPECIAL_H + +/* + * See more info about struct exception_table_entry + * in arch/loongarch/include/asm/extable.h + */ +#define EX_ENTRY_SIZE 12 +#define EX_ORIG_OFFSET 0 +#define EX_NEW_OFFSET 4 + +/* + * See more info about struct jump_entry + * in include/linux/jump_label.h + */ +#define JUMP_ENTRY_SIZE 16 +#define JUMP_ORIG_OFFSET 0 +#define JUMP_NEW_OFFSET 4 +#define JUMP_KEY_OFFSET 8 + +/* + * See more info about struct alt_instr + * in arch/loongarch/include/asm/alternative.h + */ +#define ALT_ENTRY_SIZE 12 +#define ALT_ORIG_OFFSET 0 +#define ALT_NEW_OFFSET 4 +#define ALT_FEATURE_OFFSET 8 +#define ALT_ORIG_LEN_OFFSET 10 +#define ALT_NEW_LEN_OFFSET 11 + +#endif /* _OBJTOOL_ARCH_SPECIAL_H */ diff --git a/tools/objtool/arch/loongarch/orc.c b/tools/objtool/arch/loongarch/orc.c new file mode 100644 index 000000000000..b58c5ff443c9 --- /dev/null +++ b/tools/objtool/arch/loongarch/orc.c @@ -0,0 +1,171 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +#include <linux/objtool_types.h> +#include <asm/orc_types.h> + +#include <objtool/check.h> +#include <objtool/orc.h> +#include <objtool/warn.h> +#include <objtool/endianness.h> + +int init_orc_entry(struct orc_entry *orc, struct cfi_state *cfi, struct instruction *insn) +{ + struct cfi_reg *fp = &cfi->regs[CFI_FP]; + struct cfi_reg *ra = &cfi->regs[CFI_RA]; + + memset(orc, 0, sizeof(*orc)); + + if (!cfi) { + /* + * This is usually either unreachable nops/traps (which don't + * trigger unreachable instruction warnings), or + * STACK_FRAME_NON_STANDARD functions. + */ + orc->type = ORC_TYPE_UNDEFINED; + return 0; + } + + switch (cfi->type) { + case UNWIND_HINT_TYPE_UNDEFINED: + orc->type = ORC_TYPE_UNDEFINED; + return 0; + case UNWIND_HINT_TYPE_END_OF_STACK: + orc->type = ORC_TYPE_END_OF_STACK; + return 0; + case UNWIND_HINT_TYPE_CALL: + orc->type = ORC_TYPE_CALL; + break; + case UNWIND_HINT_TYPE_REGS: + orc->type = ORC_TYPE_REGS; + break; + case UNWIND_HINT_TYPE_REGS_PARTIAL: + orc->type = ORC_TYPE_REGS_PARTIAL; + break; + default: + ERROR_INSN(insn, "unknown unwind hint type %d", cfi->type); + return -1; + } + + orc->signal = cfi->signal; + + switch (cfi->cfa.base) { + case CFI_SP: + orc->sp_reg = ORC_REG_SP; + break; + case CFI_FP: + orc->sp_reg = ORC_REG_FP; + break; + default: + ERROR_INSN(insn, "unknown CFA base reg %d", cfi->cfa.base); + return -1; + } + + switch (fp->base) { + case CFI_UNDEFINED: + orc->fp_reg = ORC_REG_UNDEFINED; + orc->fp_offset = 0; + break; + case CFI_CFA: + orc->fp_reg = ORC_REG_PREV_SP; + orc->fp_offset = fp->offset; + break; + case CFI_FP: + orc->fp_reg = ORC_REG_FP; + break; + default: + ERROR_INSN(insn, "unknown FP base reg %d", fp->base); + return -1; + } + + switch (ra->base) { + case CFI_UNDEFINED: + orc->ra_reg = ORC_REG_UNDEFINED; + orc->ra_offset = 0; + break; + case CFI_CFA: + orc->ra_reg = ORC_REG_PREV_SP; + orc->ra_offset = ra->offset; + break; + case CFI_FP: + orc->ra_reg = ORC_REG_FP; + break; + default: + ERROR_INSN(insn, "unknown RA base reg %d", ra->base); + return -1; + } + + orc->sp_offset = cfi->cfa.offset; + + return 0; +} + +int write_orc_entry(struct elf *elf, struct section *orc_sec, + struct section *ip_sec, unsigned int idx, + struct section *insn_sec, unsigned long insn_off, + struct orc_entry *o) +{ + struct orc_entry *orc; + + /* populate ORC data */ + orc = (struct orc_entry *)orc_sec->data->d_buf + idx; + memcpy(orc, o, sizeof(*orc)); + + /* populate reloc for ip */ + if (!elf_init_reloc_text_sym(elf, ip_sec, idx * sizeof(int), idx, + insn_sec, insn_off)) + return -1; + + return 0; +} + +static const char *reg_name(unsigned int reg) +{ + switch (reg) { + case ORC_REG_SP: + return "sp"; + case ORC_REG_FP: + return "fp"; + case ORC_REG_PREV_SP: + return "prevsp"; + default: + return "?"; + } +} + +static const char *orc_type_name(unsigned int type) +{ + switch (type) { + case UNWIND_HINT_TYPE_CALL: + return "call"; + case UNWIND_HINT_TYPE_REGS: + return "regs"; + case UNWIND_HINT_TYPE_REGS_PARTIAL: + return "regs (partial)"; + default: + return "?"; + } +} + +static void print_reg(unsigned int reg, int offset) +{ + if (reg == ORC_REG_UNDEFINED) + printf(" (und) "); + else + printf("%s + %3d", reg_name(reg), offset); + +} + +void orc_print_dump(struct elf *dummy_elf, struct orc_entry *orc, int i) +{ + printf("type:%s", orc_type_name(orc[i].type)); + + printf(" sp:"); + print_reg(orc[i].sp_reg, orc[i].sp_offset); + + printf(" fp:"); + print_reg(orc[i].fp_reg, orc[i].fp_offset); + + printf(" ra:"); + print_reg(orc[i].ra_reg, orc[i].ra_offset); + + printf(" signal:%d\n", orc[i].signal); +} diff --git a/tools/objtool/arch/loongarch/special.c b/tools/objtool/arch/loongarch/special.c new file mode 100644 index 000000000000..e39f86d97002 --- /dev/null +++ b/tools/objtool/arch/loongarch/special.c @@ -0,0 +1,173 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +#include <string.h> +#include <objtool/special.h> +#include <objtool/warn.h> + +bool arch_support_alt_relocation(struct special_alt *special_alt, + struct instruction *insn, + struct reloc *reloc) +{ + return false; +} + +struct table_info { + struct list_head jump_info; + unsigned long insn_offset; + unsigned long rodata_offset; +}; + +static void get_rodata_table_size_by_table_annotate(struct objtool_file *file, + struct instruction *insn, + unsigned long *table_size) +{ + struct section *rsec; + struct reloc *reloc; + struct list_head table_list; + struct table_info *orig_table; + struct table_info *next_table; + unsigned long tmp_insn_offset; + unsigned long tmp_rodata_offset; + + rsec = find_section_by_name(file->elf, ".rela.discard.tablejump_annotate"); + if (!rsec) + return; + + INIT_LIST_HEAD(&table_list); + + for_each_reloc(rsec, reloc) { + orig_table = malloc(sizeof(struct table_info)); + if (!orig_table) { + WARN("malloc failed"); + return; + } + + orig_table->insn_offset = reloc->sym->offset + reloc_addend(reloc); + reloc++; + orig_table->rodata_offset = reloc->sym->offset + reloc_addend(reloc); + + list_add_tail(&orig_table->jump_info, &table_list); + + if (reloc_idx(reloc) + 1 == sec_num_entries(rsec)) + break; + } + + list_for_each_entry(orig_table, &table_list, jump_info) { + next_table = list_next_entry(orig_table, jump_info); + list_for_each_entry_from(next_table, &table_list, jump_info) { + if (next_table->rodata_offset < orig_table->rodata_offset) { + tmp_insn_offset = next_table->insn_offset; + tmp_rodata_offset = next_table->rodata_offset; + next_table->insn_offset = orig_table->insn_offset; + next_table->rodata_offset = orig_table->rodata_offset; + orig_table->insn_offset = tmp_insn_offset; + orig_table->rodata_offset = tmp_rodata_offset; + } + } + } + + list_for_each_entry(orig_table, &table_list, jump_info) { + if (insn->offset == orig_table->insn_offset) { + next_table = list_next_entry(orig_table, jump_info); + if (&next_table->jump_info == &table_list) { + *table_size = 0; + return; + } + + while (next_table->rodata_offset == orig_table->rodata_offset) { + next_table = list_next_entry(next_table, jump_info); + if (&next_table->jump_info == &table_list) { + *table_size = 0; + return; + } + } + + *table_size = next_table->rodata_offset - orig_table->rodata_offset; + } + } +} + +static struct reloc *find_reloc_by_table_annotate(struct objtool_file *file, + struct instruction *insn, + unsigned long *table_size) +{ + struct section *rsec; + struct reloc *reloc; + unsigned long offset; + + rsec = find_section_by_name(file->elf, ".rela.discard.tablejump_annotate"); + if (!rsec) + return NULL; + + for_each_reloc(rsec, reloc) { + if (reloc->sym->sec->rodata) + continue; + + if (strcmp(insn->sec->name, reloc->sym->sec->name)) + continue; + + offset = reloc->sym->offset + reloc_addend(reloc); + if (insn->offset == offset) { + get_rodata_table_size_by_table_annotate(file, insn, table_size); + reloc++; + return reloc; + } + } + + return NULL; +} + +static struct reloc *find_reloc_of_rodata_c_jump_table(struct section *sec, + unsigned long offset, + unsigned long *table_size) +{ + struct section *rsec; + struct reloc *reloc; + + rsec = sec->rsec; + if (!rsec) + return NULL; + + for_each_reloc(rsec, reloc) { + if (reloc_offset(reloc) > offset) + break; + + if (!strcmp(reloc->sym->sec->name, C_JUMP_TABLE_SECTION)) { + *table_size = 0; + return reloc; + } + } + + return NULL; +} + +struct reloc *arch_find_switch_table(struct objtool_file *file, + struct instruction *insn, + unsigned long *table_size) +{ + struct reloc *annotate_reloc; + struct reloc *rodata_reloc; + struct section *table_sec; + unsigned long table_offset; + + annotate_reloc = find_reloc_by_table_annotate(file, insn, table_size); + if (!annotate_reloc) { + annotate_reloc = find_reloc_of_rodata_c_jump_table( + insn->sec, insn->offset, table_size); + if (!annotate_reloc) + return NULL; + } + + table_sec = annotate_reloc->sym->sec; + table_offset = annotate_reloc->sym->offset + reloc_addend(annotate_reloc); + + /* + * Each table entry has a rela associated with it. The rela + * should reference text in the same function as the original + * instruction. + */ + rodata_reloc = find_reloc_by_dest(file->elf, table_sec, table_offset); + if (!rodata_reloc) + return NULL; + + return rodata_reloc; +} |