Add ELF-related definition and module relocation code for basic LoongArch support. Cc: Jessica Yu <jeyu@xxxxxxxxxx> Reviewed-by: WANG Xuerui <git@xxxxxxxxxx> Reviewed-by: Luis Chamberlain <mcgrof@xxxxxxxxxx> Reviewed-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx> Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx> --- arch/loongarch/include/asm/cpufeature.h | 24 ++ arch/loongarch/include/asm/elf.h | 301 ++++++++++++++++++ arch/loongarch/include/asm/exec.h | 10 + arch/loongarch/include/asm/module.h | 80 +++++ arch/loongarch/include/asm/module.lds.h | 7 + arch/loongarch/include/asm/vermagic.h | 19 ++ arch/loongarch/include/uapi/asm/auxvec.h | 17 ++ arch/loongarch/include/uapi/asm/hwcap.h | 20 ++ arch/loongarch/kernel/elf.c | 30 ++ arch/loongarch/kernel/inst.c | 40 +++ arch/loongarch/kernel/module-sections.c | 121 ++++++++ arch/loongarch/kernel/module.c | 374 +++++++++++++++++++++++ 12 files changed, 1043 insertions(+) create mode 100644 arch/loongarch/include/asm/cpufeature.h create mode 100644 arch/loongarch/include/asm/elf.h create mode 100644 arch/loongarch/include/asm/exec.h create mode 100644 arch/loongarch/include/asm/module.h create mode 100644 arch/loongarch/include/asm/module.lds.h create mode 100644 arch/loongarch/include/asm/vermagic.h create mode 100644 arch/loongarch/include/uapi/asm/auxvec.h create mode 100644 arch/loongarch/include/uapi/asm/hwcap.h create mode 100644 arch/loongarch/kernel/elf.c create mode 100644 arch/loongarch/kernel/inst.c create mode 100644 arch/loongarch/kernel/module-sections.c create mode 100644 arch/loongarch/kernel/module.c diff --git a/arch/loongarch/include/asm/cpufeature.h b/arch/loongarch/include/asm/cpufeature.h new file mode 100644 index 000000000000..4da22a8e63de --- /dev/null +++ b/arch/loongarch/include/asm/cpufeature.h @@ -0,0 +1,24 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * CPU feature definitions for module loading, used by + * module_cpu_feature_match(), see uapi/asm/hwcap.h for LoongArch CPU features. + * + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ + +#ifndef __ASM_CPUFEATURE_H +#define __ASM_CPUFEATURE_H + +#include <uapi/asm/hwcap.h> +#include <asm/elf.h> + +#define MAX_CPU_FEATURES (8 * sizeof(elf_hwcap)) + +#define cpu_feature(x) ilog2(HWCAP_ ## x) + +static inline bool cpu_have_feature(unsigned int num) +{ + return elf_hwcap & (1UL << num); +} + +#endif /* __ASM_CPUFEATURE_H */ diff --git a/arch/loongarch/include/asm/elf.h b/arch/loongarch/include/asm/elf.h new file mode 100644 index 000000000000..f3960b18a90e --- /dev/null +++ b/arch/loongarch/include/asm/elf.h @@ -0,0 +1,301 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#ifndef _ASM_ELF_H +#define _ASM_ELF_H + +#include <linux/auxvec.h> +#include <linux/fs.h> +#include <uapi/linux/elf.h> + +#include <asm/current.h> +#include <asm/vdso.h> + +/* The ABI of a file. */ +#define EF_LOONGARCH_ABI_LP64_SOFT_FLOAT 0x1 +#define EF_LOONGARCH_ABI_LP64_SINGLE_FLOAT 0x2 +#define EF_LOONGARCH_ABI_LP64_DOUBLE_FLOAT 0x3 + +#define EF_LOONGARCH_ABI_ILP32_SOFT_FLOAT 0x5 +#define EF_LOONGARCH_ABI_ILP32_SINGLE_FLOAT 0x6 +#define EF_LOONGARCH_ABI_ILP32_DOUBLE_FLOAT 0x7 + +/* LoongArch relocation types used by the dynamic linker */ +#define R_LARCH_NONE 0 +#define R_LARCH_32 1 +#define R_LARCH_64 2 +#define R_LARCH_RELATIVE 3 +#define R_LARCH_COPY 4 +#define R_LARCH_JUMP_SLOT 5 +#define R_LARCH_TLS_DTPMOD32 6 +#define R_LARCH_TLS_DTPMOD64 7 +#define R_LARCH_TLS_DTPREL32 8 +#define R_LARCH_TLS_DTPREL64 9 +#define R_LARCH_TLS_TPREL32 10 +#define R_LARCH_TLS_TPREL64 11 +#define R_LARCH_IRELATIVE 12 +#define R_LARCH_MARK_LA 20 +#define R_LARCH_MARK_PCREL 21 +#define R_LARCH_SOP_PUSH_PCREL 22 +#define R_LARCH_SOP_PUSH_ABSOLUTE 23 +#define R_LARCH_SOP_PUSH_DUP 24 +#define R_LARCH_SOP_PUSH_GPREL 25 +#define R_LARCH_SOP_PUSH_TLS_TPREL 26 +#define R_LARCH_SOP_PUSH_TLS_GOT 27 +#define R_LARCH_SOP_PUSH_TLS_GD 28 +#define R_LARCH_SOP_PUSH_PLT_PCREL 29 +#define R_LARCH_SOP_ASSERT 30 +#define R_LARCH_SOP_NOT 31 +#define R_LARCH_SOP_SUB 32 +#define R_LARCH_SOP_SL 33 +#define R_LARCH_SOP_SR 34 +#define R_LARCH_SOP_ADD 35 +#define R_LARCH_SOP_AND 36 +#define R_LARCH_SOP_IF_ELSE 37 +#define R_LARCH_SOP_POP_32_S_10_5 38 +#define R_LARCH_SOP_POP_32_U_10_12 39 +#define R_LARCH_SOP_POP_32_S_10_12 40 +#define R_LARCH_SOP_POP_32_S_10_16 41 +#define R_LARCH_SOP_POP_32_S_10_16_S2 42 +#define R_LARCH_SOP_POP_32_S_5_20 43 +#define R_LARCH_SOP_POP_32_S_0_5_10_16_S2 44 +#define R_LARCH_SOP_POP_32_S_0_10_10_16_S2 45 +#define R_LARCH_SOP_POP_32_U 46 +#define R_LARCH_ADD8 47 +#define R_LARCH_ADD16 48 +#define R_LARCH_ADD24 49 +#define R_LARCH_ADD32 50 +#define R_LARCH_ADD64 51 +#define R_LARCH_SUB8 52 +#define R_LARCH_SUB16 53 +#define R_LARCH_SUB24 54 +#define R_LARCH_SUB32 55 +#define R_LARCH_SUB64 56 +#define R_LARCH_GNU_VTINHERIT 57 +#define R_LARCH_GNU_VTENTRY 58 + +#ifndef ELF_ARCH + +/* ELF register definitions */ + +/* + * General purpose have the following registers: + * Register Number + * GPRs 32 + * ORIG_A0 1 + * ERA 1 + * BADVADDR 1 + * CRMD 1 + * PRMD 1 + * EUEN 1 + * ECFG 1 + * ESTAT 1 + * Reserved 5 + */ +#define ELF_NGREG 45 + +/* + * Floating point have the following registers: + * Register Number + * FPR 32 + * FCC 1 + * FCSR 1 + */ +#define ELF_NFPREG 34 + +typedef unsigned long elf_greg_t; +typedef elf_greg_t elf_gregset_t[ELF_NGREG]; + +typedef double elf_fpreg_t; +typedef elf_fpreg_t elf_fpregset_t[ELF_NFPREG]; + +void loongarch_dump_regs64(u64 *uregs, const struct pt_regs *regs); + +#ifdef CONFIG_32BIT +/* + * This is used to ensure we don't load something for the wrong architecture. + */ +#define elf_check_arch elf32_check_arch + +/* + * These are used to set parameters in the core dumps. + */ +#define ELF_CLASS ELFCLASS32 + +#define ELF_CORE_COPY_REGS(dest, regs) \ + loongarch_dump_regs32((u32 *)&(dest), (regs)); + +#endif /* CONFIG_32BIT */ + +#ifdef CONFIG_64BIT +/* + * This is used to ensure we don't load something for the wrong architecture. + */ +#define elf_check_arch elf64_check_arch + +/* + * These are used to set parameters in the core dumps. + */ +#define ELF_CLASS ELFCLASS64 + +#define ELF_CORE_COPY_REGS(dest, regs) \ + loongarch_dump_regs64((u64 *)&(dest), (regs)); + +#endif /* CONFIG_64BIT */ + +/* + * These are used to set parameters in the core dumps. + */ +#define ELF_DATA ELFDATA2LSB +#define ELF_ARCH EM_LOONGARCH + +#endif /* !defined(ELF_ARCH) */ + +#define loongarch_elf_check_machine(x) ((x)->e_machine == EM_LOONGARCH) + +#define vmcore_elf32_check_arch loongarch_elf_check_machine +#define vmcore_elf64_check_arch loongarch_elf_check_machine + +/* + * Return non-zero if HDR identifies an 32bit ELF binary. + */ +#define elf32_check_arch(hdr) \ +({ \ + int __res = 1; \ + struct elfhdr *__h = (hdr); \ + \ + if (!loongarch_elf_check_machine(__h)) \ + __res = 0; \ + if (__h->e_ident[EI_CLASS] != ELFCLASS32) \ + __res = 0; \ + \ + __res; \ +}) + +/* + * Return non-zero if HDR identifies an 64bit ELF binary. + */ +#define elf64_check_arch(hdr) \ +({ \ + int __res = 1; \ + struct elfhdr *__h = (hdr); \ + \ + if (!loongarch_elf_check_machine(__h)) \ + __res = 0; \ + if (__h->e_ident[EI_CLASS] != ELFCLASS64) \ + __res = 0; \ + \ + __res; \ +}) + +#ifdef CONFIG_32BIT + +#define SET_PERSONALITY2(ex, state) \ +do { \ + current->thread.vdso = &vdso_info; \ + \ + loongarch_set_personality_fcsr(state); \ + \ + if (personality(current->personality) != PER_LINUX) \ + set_personality(PER_LINUX); \ +} while (0) + +#endif /* CONFIG_32BIT */ + +#ifdef CONFIG_64BIT + +#define SET_PERSONALITY2(ex, state) \ +do { \ + unsigned int p; \ + \ + clear_thread_flag(TIF_32BIT_REGS); \ + clear_thread_flag(TIF_32BIT_ADDR); \ + \ + current->thread.vdso = &vdso_info; \ + loongarch_set_personality_fcsr(state); \ + \ + p = personality(current->personality); \ + if (p != PER_LINUX32 && p != PER_LINUX) \ + set_personality(PER_LINUX); \ +} while (0) + +#endif /* CONFIG_64BIT */ + +#define CORE_DUMP_USE_REGSET +#define ELF_EXEC_PAGESIZE PAGE_SIZE + +/* + * This yields a mask that user programs can use to figure out what + * instruction set this cpu supports. This could be done in userspace, + * but it's not easy, and we've already done it here. + */ + +#define ELF_HWCAP (elf_hwcap) +extern unsigned int elf_hwcap; +#include <asm/hwcap.h> + +/* + * This yields a string that ld.so will use to load implementation + * specific libraries for optimization. This is more specific in + * intent than poking at uname or /proc/cpuinfo. + */ + +#define ELF_PLATFORM __elf_platform +extern const char *__elf_platform; + +#define ELF_PLAT_INIT(_r, load_addr) do { \ + _r->regs[1] = _r->regs[2] = _r->regs[3] = _r->regs[4] = 0; \ + _r->regs[5] = _r->regs[6] = _r->regs[7] = _r->regs[8] = 0; \ + _r->regs[9] = _r->regs[10] = _r->regs[11] = _r->regs[12] = 0; \ + _r->regs[13] = _r->regs[14] = _r->regs[15] = _r->regs[16] = 0; \ + _r->regs[17] = _r->regs[18] = _r->regs[19] = _r->regs[20] = 0; \ + _r->regs[21] = _r->regs[22] = _r->regs[23] = _r->regs[24] = 0; \ + _r->regs[25] = _r->regs[26] = _r->regs[27] = _r->regs[28] = 0; \ + _r->regs[29] = _r->regs[30] = _r->regs[31] = 0; \ +} while (0) + +/* + * This is the location that an ET_DYN program is loaded if exec'ed. Typical + * use of this is to invoke "./ld.so someprog" to test out a new version of + * the loader. We need to make sure that it is out of the way of the program + * that it will "exec", and that there is sufficient room for the brk. + */ + +#define ELF_ET_DYN_BASE (TASK_SIZE / 3 * 2) + +/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */ +#define ARCH_DLINFO \ +do { \ + NEW_AUX_ENT(AT_SYSINFO_EHDR, \ + (unsigned long)current->mm->context.vdso); \ +} while (0) + +#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1 +struct linux_binprm; +extern int arch_setup_additional_pages(struct linux_binprm *bprm, + int uses_interp); + +struct arch_elf_state { + int fp_abi; + int interp_fp_abi; +}; + +#define LOONGARCH_ABI_FP_ANY (0) + +#define INIT_ARCH_ELF_STATE { \ + .fp_abi = LOONGARCH_ABI_FP_ANY, \ + .interp_fp_abi = LOONGARCH_ABI_FP_ANY, \ +} + +#define elf_read_implies_exec(ex, exec_stk) (exec_stk == EXSTACK_DEFAULT) + +extern int arch_elf_pt_proc(void *ehdr, void *phdr, struct file *elf, + bool is_interp, struct arch_elf_state *state); + +extern int arch_check_elf(void *ehdr, bool has_interpreter, void *interp_ehdr, + struct arch_elf_state *state); + +extern void loongarch_set_personality_fcsr(struct arch_elf_state *state); + +#endif /* _ASM_ELF_H */ diff --git a/arch/loongarch/include/asm/exec.h b/arch/loongarch/include/asm/exec.h new file mode 100644 index 000000000000..ba0220812ebb --- /dev/null +++ b/arch/loongarch/include/asm/exec.h @@ -0,0 +1,10 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#ifndef _ASM_EXEC_H +#define _ASM_EXEC_H + +extern unsigned long arch_align_stack(unsigned long sp); + +#endif /* _ASM_EXEC_H */ diff --git a/arch/loongarch/include/asm/module.h b/arch/loongarch/include/asm/module.h new file mode 100644 index 000000000000..9f6718df1854 --- /dev/null +++ b/arch/loongarch/include/asm/module.h @@ -0,0 +1,80 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#ifndef _ASM_MODULE_H +#define _ASM_MODULE_H + +#include <asm/inst.h> +#include <asm-generic/module.h> + +#define RELA_STACK_DEPTH 16 + +struct mod_section { + Elf_Shdr *shdr; + int num_entries; + int max_entries; +}; + +struct mod_arch_specific { + struct mod_section plt; + struct mod_section plt_idx; +}; + +struct plt_entry { + u32 inst_lu12iw; + u32 inst_lu32id; + u32 inst_lu52id; + u32 inst_jirl; +}; + +struct plt_idx_entry { + unsigned long symbol_addr; +}; + +Elf_Addr module_emit_plt_entry(struct module *mod, unsigned long val); + +static inline struct plt_entry emit_plt_entry(unsigned long val) +{ + u32 lu12iw, lu32id, lu52id, jirl; + + lu12iw = (lu12iw_op << 25 | (((val >> 12) & 0xfffff) << 5) | LOONGARCH_GPR_T1); + lu32id = larch_insn_gen_lu32id(LOONGARCH_GPR_T1, ADDR_IMM(val, LU32ID)); + lu52id = larch_insn_gen_lu52id(LOONGARCH_GPR_T1, LOONGARCH_GPR_T1, ADDR_IMM(val, LU52ID)); + jirl = larch_insn_gen_jirl(0, LOONGARCH_GPR_T1, 0, (val & 0xfff)); + + return (struct plt_entry) { lu12iw, lu32id, lu52id, jirl }; +} + +static inline struct plt_idx_entry emit_plt_idx_entry(unsigned long val) +{ + return (struct plt_idx_entry) { val }; +} + +static inline int get_plt_idx(unsigned long val, const struct mod_section *sec) +{ + int i; + struct plt_idx_entry *plt_idx = (struct plt_idx_entry *)sec->shdr->sh_addr; + + for (i = 0; i < sec->num_entries; i++) { + if (plt_idx[i].symbol_addr == val) + return i; + } + + return -1; +} + +static inline struct plt_entry *get_plt_entry(unsigned long val, + const struct mod_section *sec_plt, + const struct mod_section *sec_plt_idx) +{ + int plt_idx = get_plt_idx(val, sec_plt_idx); + struct plt_entry *plt = (struct plt_entry *)sec_plt->shdr->sh_addr; + + if (plt_idx < 0) + return NULL; + + return plt + plt_idx; +} + +#endif /* _ASM_MODULE_H */ diff --git a/arch/loongarch/include/asm/module.lds.h b/arch/loongarch/include/asm/module.lds.h new file mode 100644 index 000000000000..31c1c0db11a3 --- /dev/null +++ b/arch/loongarch/include/asm/module.lds.h @@ -0,0 +1,7 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright (C) 2020-2022 Loongson Technology Corporation Limited */ +SECTIONS { + . = ALIGN(4); + .plt : { BYTE(0) } + .plt.idx : { BYTE(0) } +} diff --git a/arch/loongarch/include/asm/vermagic.h b/arch/loongarch/include/asm/vermagic.h new file mode 100644 index 000000000000..8b47ccfe3aad --- /dev/null +++ b/arch/loongarch/include/asm/vermagic.h @@ -0,0 +1,19 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#ifndef _ASM_VERMAGIC_H +#define _ASM_VERMAGIC_H + +#define MODULE_PROC_FAMILY "LOONGARCH " + +#ifdef CONFIG_32BIT +#define MODULE_KERNEL_TYPE "32BIT " +#elif defined CONFIG_64BIT +#define MODULE_KERNEL_TYPE "64BIT " +#endif + +#define MODULE_ARCH_VERMAGIC \ + MODULE_PROC_FAMILY MODULE_KERNEL_TYPE + +#endif /* _ASM_VERMAGIC_H */ diff --git a/arch/loongarch/include/uapi/asm/auxvec.h b/arch/loongarch/include/uapi/asm/auxvec.h new file mode 100644 index 000000000000..922d9e6b5058 --- /dev/null +++ b/arch/loongarch/include/uapi/asm/auxvec.h @@ -0,0 +1,17 @@ +/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */ +/* + * Author: Hanlu Li <lihanlu@xxxxxxxxxxx> + * Huacai Chen <chenhuacai@xxxxxxxxxxx> + * + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ + +#ifndef __ASM_AUXVEC_H +#define __ASM_AUXVEC_H + +/* Location of VDSO image. */ +#define AT_SYSINFO_EHDR 33 + +#define AT_VECTOR_SIZE_ARCH 1 /* entries in ARCH_DLINFO */ + +#endif /* __ASM_AUXVEC_H */ diff --git a/arch/loongarch/include/uapi/asm/hwcap.h b/arch/loongarch/include/uapi/asm/hwcap.h new file mode 100644 index 000000000000..8840b72fa8e8 --- /dev/null +++ b/arch/loongarch/include/uapi/asm/hwcap.h @@ -0,0 +1,20 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +#ifndef _UAPI_ASM_HWCAP_H +#define _UAPI_ASM_HWCAP_H + +/* HWCAP flags */ +#define HWCAP_LOONGARCH_CPUCFG (1 << 0) +#define HWCAP_LOONGARCH_LAM (1 << 1) +#define HWCAP_LOONGARCH_UAL (1 << 2) +#define HWCAP_LOONGARCH_FPU (1 << 3) +#define HWCAP_LOONGARCH_LSX (1 << 4) +#define HWCAP_LOONGARCH_LASX (1 << 5) +#define HWCAP_LOONGARCH_CRC32 (1 << 6) +#define HWCAP_LOONGARCH_COMPLEX (1 << 7) +#define HWCAP_LOONGARCH_CRYPTO (1 << 8) +#define HWCAP_LOONGARCH_LVZ (1 << 9) +#define HWCAP_LOONGARCH_LBT_X86 (1 << 10) +#define HWCAP_LOONGARCH_LBT_ARM (1 << 11) +#define HWCAP_LOONGARCH_LBT_MIPS (1 << 12) + +#endif /* _UAPI_ASM_HWCAP_H */ diff --git a/arch/loongarch/kernel/elf.c b/arch/loongarch/kernel/elf.c new file mode 100644 index 000000000000..183e94fc9c69 --- /dev/null +++ b/arch/loongarch/kernel/elf.c @@ -0,0 +1,30 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Author: Huacai Chen <chenhuacai@xxxxxxxxxxx> + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ + +#include <linux/binfmts.h> +#include <linux/elf.h> +#include <linux/export.h> +#include <linux/sched.h> + +#include <asm/cpu-features.h> +#include <asm/cpu-info.h> + +int arch_elf_pt_proc(void *_ehdr, void *_phdr, struct file *elf, + bool is_interp, struct arch_elf_state *state) +{ + return 0; +} + +int arch_check_elf(void *_ehdr, bool has_interpreter, void *_interp_ehdr, + struct arch_elf_state *state) +{ + return 0; +} + +void loongarch_set_personality_fcsr(struct arch_elf_state *state) +{ + current->thread.fpu.fcsr = boot_cpu_data.fpu_csr0; +} diff --git a/arch/loongarch/kernel/inst.c b/arch/loongarch/kernel/inst.c new file mode 100644 index 000000000000..b1df0ec34bd1 --- /dev/null +++ b/arch/loongarch/kernel/inst.c @@ -0,0 +1,40 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#include <asm/inst.h> + +u32 larch_insn_gen_lu32id(enum loongarch_gpr rd, int imm) +{ + union loongarch_instruction insn; + + insn.reg1i20_format.opcode = lu32id_op; + insn.reg1i20_format.rd = rd; + insn.reg1i20_format.immediate = imm; + + return insn.word; +} + +u32 larch_insn_gen_lu52id(enum loongarch_gpr rd, enum loongarch_gpr rj, int imm) +{ + union loongarch_instruction insn; + + insn.reg2i12_format.opcode = lu52id_op; + insn.reg2i12_format.rd = rd; + insn.reg2i12_format.rj = rj; + insn.reg2i12_format.immediate = imm; + + return insn.word; +} + +u32 larch_insn_gen_jirl(enum loongarch_gpr rd, enum loongarch_gpr rj, unsigned long pc, unsigned long dest) +{ + union loongarch_instruction insn; + + insn.reg2i16_format.opcode = jirl_op; + insn.reg2i16_format.rd = rd; + insn.reg2i16_format.rj = rj; + insn.reg2i16_format.immediate = (dest - pc) >> 2; + + return insn.word; +} diff --git a/arch/loongarch/kernel/module-sections.c b/arch/loongarch/kernel/module-sections.c new file mode 100644 index 000000000000..6d498288977d --- /dev/null +++ b/arch/loongarch/kernel/module-sections.c @@ -0,0 +1,121 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ + +#include <linux/elf.h> +#include <linux/kernel.h> +#include <linux/module.h> + +Elf_Addr module_emit_plt_entry(struct module *mod, unsigned long val) +{ + int nr; + struct mod_section *plt_sec = &mod->arch.plt; + struct mod_section *plt_idx_sec = &mod->arch.plt_idx; + struct plt_entry *plt = get_plt_entry(val, plt_sec, plt_idx_sec); + struct plt_idx_entry *plt_idx; + + if (plt) + return (Elf_Addr)plt; + + nr = plt_sec->num_entries; + + /* There is no duplicate entry, create a new one */ + plt = (struct plt_entry *)plt_sec->shdr->sh_addr; + plt[nr] = emit_plt_entry(val); + plt_idx = (struct plt_idx_entry *)plt_idx_sec->shdr->sh_addr; + plt_idx[nr] = emit_plt_idx_entry(val); + + plt_sec->num_entries++; + plt_idx_sec->num_entries++; + BUG_ON(plt_sec->num_entries > plt_sec->max_entries); + + return (Elf_Addr)&plt[nr]; +} + +static int is_rela_equal(const Elf_Rela *x, const Elf_Rela *y) +{ + return x->r_info == y->r_info && x->r_addend == y->r_addend; +} + +static bool duplicate_rela(const Elf_Rela *rela, int idx) +{ + int i; + + for (i = 0; i < idx; i++) { + if (is_rela_equal(&rela[i], &rela[idx])) + return true; + } + + return false; +} + +static void count_max_entries(Elf_Rela *relas, int num, unsigned int *plts) +{ + unsigned int i, type; + + for (i = 0; i < num; i++) { + type = ELF_R_TYPE(relas[i].r_info); + if (type == R_LARCH_SOP_PUSH_PLT_PCREL) { + if (!duplicate_rela(relas, i)) + (*plts)++; + } + } +} + +int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs, + char *secstrings, struct module *mod) +{ + unsigned int i, num_plts = 0; + + /* + * Find the empty .plt sections. + */ + for (i = 0; i < ehdr->e_shnum; i++) { + if (!strcmp(secstrings + sechdrs[i].sh_name, ".plt")) + mod->arch.plt.shdr = sechdrs + i; + else if (!strcmp(secstrings + sechdrs[i].sh_name, ".plt.idx")) + mod->arch.plt_idx.shdr = sechdrs + i; + } + + if (!mod->arch.plt.shdr) { + pr_err("%s: module PLT section(s) missing\n", mod->name); + return -ENOEXEC; + } + if (!mod->arch.plt_idx.shdr) { + pr_err("%s: module PLT.IDX section(s) missing\n", mod->name); + return -ENOEXEC; + } + + /* Calculate the maxinum number of entries */ + for (i = 0; i < ehdr->e_shnum; i++) { + int num_rela = sechdrs[i].sh_size / sizeof(Elf_Rela); + Elf_Rela *relas = (void *)ehdr + sechdrs[i].sh_offset; + Elf_Shdr *dst_sec = sechdrs + sechdrs[i].sh_info; + + if (sechdrs[i].sh_type != SHT_RELA) + continue; + + /* ignore relocations that operate on non-exec sections */ + if (!(dst_sec->sh_flags & SHF_EXECINSTR)) + continue; + + count_max_entries(relas, num_rela, &num_plts); + } + + mod->arch.plt.shdr->sh_type = SHT_NOBITS; + mod->arch.plt.shdr->sh_flags = SHF_EXECINSTR | SHF_ALLOC; + mod->arch.plt.shdr->sh_addralign = L1_CACHE_BYTES; + mod->arch.plt.shdr->sh_size = (num_plts + 1) * sizeof(struct plt_entry); + mod->arch.plt.num_entries = 0; + mod->arch.plt.max_entries = num_plts; + + mod->arch.plt_idx.shdr->sh_type = SHT_NOBITS; + mod->arch.plt_idx.shdr->sh_flags = SHF_ALLOC; + mod->arch.plt_idx.shdr->sh_addralign = L1_CACHE_BYTES; + mod->arch.plt_idx.shdr->sh_size = (num_plts + 1) * sizeof(struct plt_idx_entry); + mod->arch.plt_idx.num_entries = 0; + mod->arch.plt_idx.max_entries = num_plts; + + return 0; +} diff --git a/arch/loongarch/kernel/module.c b/arch/loongarch/kernel/module.c new file mode 100644 index 000000000000..87b3768f1eef --- /dev/null +++ b/arch/loongarch/kernel/module.c @@ -0,0 +1,374 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Author: Hanlu Li <lihanlu@xxxxxxxxxxx> + * Huacai Chen <chenhuacai@xxxxxxxxxxx> + * + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ + +#define pr_fmt(fmt) "kmod: " fmt + +#include <linux/moduleloader.h> +#include <linux/elf.h> +#include <linux/mm.h> +#include <linux/vmalloc.h> +#include <linux/slab.h> +#include <linux/fs.h> +#include <linux/string.h> +#include <linux/kernel.h> + +static inline bool signed_imm_check(long val, unsigned int bit) +{ + return -(1L << (bit - 1)) <= val && val < (1L << (bit - 1)); +} + +static inline bool unsigned_imm_check(unsigned long val, unsigned int bit) +{ + return val < (1UL << bit); +} + +static int rela_stack_push(s64 stack_value, s64 *rela_stack, size_t *rela_stack_top) +{ + if (*rela_stack_top >= RELA_STACK_DEPTH) + return -ENOEXEC; + + rela_stack[(*rela_stack_top)++] = stack_value; + pr_debug("%s stack_value = 0x%llx\n", __func__, stack_value); + + return 0; +} + +static int rela_stack_pop(s64 *stack_value, s64 *rela_stack, size_t *rela_stack_top) +{ + if (*rela_stack_top == 0) + return -ENOEXEC; + + *stack_value = rela_stack[--(*rela_stack_top)]; + pr_debug("%s stack_value = 0x%llx\n", __func__, *stack_value); + + return 0; +} + +static int apply_r_larch_none(struct module *mod, u32 *location, Elf_Addr v, + s64 *rela_stack, size_t *rela_stack_top, unsigned int type) +{ + return 0; +} + +static int apply_r_larch_error(struct module *me, u32 *location, Elf_Addr v, + s64 *rela_stack, size_t *rela_stack_top, unsigned int type) +{ + pr_err("%s: Unsupport relocation type %u, please add its support.\n", me->name, type); + return -EINVAL; +} + +static int apply_r_larch_32(struct module *mod, u32 *location, Elf_Addr v, + s64 *rela_stack, size_t *rela_stack_top, unsigned int type) +{ + *location = v; + return 0; +} + +static int apply_r_larch_64(struct module *mod, u32 *location, Elf_Addr v, + s64 *rela_stack, size_t *rela_stack_top, unsigned int type) +{ + *(Elf_Addr *)location = v; + return 0; +} + +static int apply_r_larch_sop_push_pcrel(struct module *mod, u32 *location, Elf_Addr v, + s64 *rela_stack, size_t *rela_stack_top, unsigned int type) +{ + return rela_stack_push(v - (u64)location, rela_stack, rela_stack_top); +} + +static int apply_r_larch_sop_push_absolute(struct module *mod, u32 *location, Elf_Addr v, + s64 *rela_stack, size_t *rela_stack_top, unsigned int type) +{ + return rela_stack_push(v, rela_stack, rela_stack_top); +} + +static int apply_r_larch_sop_push_dup(struct module *mod, u32 *location, Elf_Addr v, + s64 *rela_stack, size_t *rela_stack_top, unsigned int type) +{ + int err = 0; + s64 opr1; + + err = rela_stack_pop(&opr1, rela_stack, rela_stack_top); + if (err) + return err; + err = rela_stack_push(opr1, rela_stack, rela_stack_top); + if (err) + return err; + err = rela_stack_push(opr1, rela_stack, rela_stack_top); + if (err) + return err; + + return 0; +} + +static int apply_r_larch_sop_push_plt_pcrel(struct module *mod, u32 *location, Elf_Addr v, + s64 *rela_stack, size_t *rela_stack_top, unsigned int type) +{ + ptrdiff_t offset = (void *)v - (void *)location; + + if (offset >= SZ_128M) + v = module_emit_plt_entry(mod, v); + + if (offset < -SZ_128M) + v = module_emit_plt_entry(mod, v); + + return apply_r_larch_sop_push_pcrel(mod, location, v, rela_stack, rela_stack_top, type); +} + +static int apply_r_larch_sop(struct module *mod, u32 *location, Elf_Addr v, + s64 *rela_stack, size_t *rela_stack_top, unsigned int type) +{ + int err = 0; + s64 opr1, opr2, opr3; + + if (type == R_LARCH_SOP_IF_ELSE) { + err = rela_stack_pop(&opr3, rela_stack, rela_stack_top); + if (err) + return err; + } + + err = rela_stack_pop(&opr2, rela_stack, rela_stack_top); + if (err) + return err; + err = rela_stack_pop(&opr1, rela_stack, rela_stack_top); + if (err) + return err; + + switch (type) { + case R_LARCH_SOP_AND: + err = rela_stack_push(opr1 & opr2, rela_stack, rela_stack_top); + break; + case R_LARCH_SOP_ADD: + err = rela_stack_push(opr1 + opr2, rela_stack, rela_stack_top); + break; + case R_LARCH_SOP_SUB: + err = rela_stack_push(opr1 - opr2, rela_stack, rela_stack_top); + break; + case R_LARCH_SOP_SL: + err = rela_stack_push(opr1 << opr2, rela_stack, rela_stack_top); + break; + case R_LARCH_SOP_SR: + err = rela_stack_push(opr1 >> opr2, rela_stack, rela_stack_top); + break; + case R_LARCH_SOP_IF_ELSE: + err = rela_stack_push(opr1 ? opr2 : opr3, rela_stack, rela_stack_top); + break; + default: + pr_err("%s: Unsupport relocation type %u\n", mod->name, type); + return -EINVAL; + } + + return err; +} + +static int apply_r_larch_sop_imm_field(struct module *mod, u32 *location, Elf_Addr v, + s64 *rela_stack, size_t *rela_stack_top, unsigned int type) +{ + int err = 0; + s64 opr1; + union loongarch_instruction *insn = (union loongarch_instruction *)location; + + err = rela_stack_pop(&opr1, rela_stack, rela_stack_top); + if (err) + return err; + + switch (type) { + case R_LARCH_SOP_POP_32_U_10_12: + if (!unsigned_imm_check(opr1, 12)) + goto overflow; + + /* (*(uint32_t *) PC) [21 ... 10] = opr [11 ... 0] */ + insn->reg2i12_format.immediate = opr1 & 0xfff; + return 0; + case R_LARCH_SOP_POP_32_S_10_12: + if (!signed_imm_check(opr1, 12)) + goto overflow; + + insn->reg2i12_format.immediate = opr1 & 0xfff; + return 0; + case R_LARCH_SOP_POP_32_S_10_16: + if (!signed_imm_check(opr1, 16)) + goto overflow; + + insn->reg2i16_format.immediate = opr1 & 0xffff; + return 0; + case R_LARCH_SOP_POP_32_S_10_16_S2: + if (opr1 % 4) + goto unaligned; + + if (!signed_imm_check(opr1, 18)) + goto overflow; + + insn->reg2i16_format.immediate = (opr1 >> 2) & 0xffff; + return 0; + case R_LARCH_SOP_POP_32_S_5_20: + if (!signed_imm_check(opr1, 20)) + goto overflow; + + insn->reg1i20_format.immediate = (opr1) & 0xfffff; + return 0; + case R_LARCH_SOP_POP_32_S_0_5_10_16_S2: + if (opr1 % 4) + goto unaligned; + + if (!signed_imm_check(opr1, 23)) + goto overflow; + + opr1 >>= 2; + insn->reg1i21_format.immediate_l = opr1 & 0xffff; + insn->reg1i21_format.immediate_h = (opr1 >> 16) & 0x1f; + return 0; + case R_LARCH_SOP_POP_32_S_0_10_10_16_S2: + if (opr1 % 4) + goto unaligned; + + if (!signed_imm_check(opr1, 28)) + goto overflow; + + opr1 >>= 2; + insn->reg0i26_format.immediate_l = opr1 & 0xffff; + insn->reg0i26_format.immediate_h = (opr1 >> 16) & 0x3ff; + return 0; + case R_LARCH_SOP_POP_32_U: + if (!unsigned_imm_check(opr1, 32)) + goto overflow; + + /* (*(uint32_t *) PC) = opr */ + *location = (u32)opr1; + return 0; + default: + pr_err("%s: Unsupport relocation type %u\n", mod->name, type); + return -EINVAL; + } + +overflow: + pr_err("module %s: opr1 = 0x%llx overflow! dangerous %s (%u) relocation\n", + mod->name, opr1, __func__, type); + return -ENOEXEC; + +unaligned: + pr_err("module %s: opr1 = 0x%llx unaligned! dangerous %s (%u) relocation\n", + mod->name, opr1, __func__, type); + return -ENOEXEC; +} + +static int apply_r_larch_add_sub(struct module *mod, u32 *location, Elf_Addr v, + s64 *rela_stack, size_t *rela_stack_top, unsigned int type) +{ + switch (type) { + case R_LARCH_ADD32: + *(s32 *)location += v; + return 0; + case R_LARCH_ADD64: + *(s64 *)location += v; + return 0; + case R_LARCH_SUB32: + *(s32 *)location -= v; + return 0; + case R_LARCH_SUB64: + *(s64 *)location -= v; + return 0; + default: + pr_err("%s: Unsupport relocation type %u\n", mod->name, type); + return -EINVAL; + } +} + +/* + * reloc_handlers_rela() - Apply a particular relocation to a module + * @mod: the module to apply the reloc to + * @location: the address at which the reloc is to be applied + * @v: the value of the reloc, with addend for RELA-style + * @rela_stack: the stack used for store relocation info, LOCAL to THIS module + * @rela_stac_top: where the stack operation(pop/push) applies to + * + * Return: 0 upon success, else -ERRNO + */ +typedef int (*reloc_rela_handler)(struct module *mod, u32 *location, Elf_Addr v, + s64 *rela_stack, size_t *rela_stack_top, unsigned int type); + +/* The handlers for known reloc types */ +static reloc_rela_handler reloc_rela_handlers[] = { + [R_LARCH_NONE ... R_LARCH_SUB64] = apply_r_larch_error, + + [R_LARCH_NONE] = apply_r_larch_none, + [R_LARCH_32] = apply_r_larch_32, + [R_LARCH_64] = apply_r_larch_64, + [R_LARCH_MARK_LA] = apply_r_larch_none, + [R_LARCH_MARK_PCREL] = apply_r_larch_none, + [R_LARCH_SOP_PUSH_PCREL] = apply_r_larch_sop_push_pcrel, + [R_LARCH_SOP_PUSH_ABSOLUTE] = apply_r_larch_sop_push_absolute, + [R_LARCH_SOP_PUSH_DUP] = apply_r_larch_sop_push_dup, + [R_LARCH_SOP_PUSH_PLT_PCREL] = apply_r_larch_sop_push_plt_pcrel, + [R_LARCH_SOP_SUB ... R_LARCH_SOP_IF_ELSE] = apply_r_larch_sop, + [R_LARCH_SOP_POP_32_S_10_5 ... R_LARCH_SOP_POP_32_U] = apply_r_larch_sop_imm_field, + [R_LARCH_ADD32 ... R_LARCH_SUB64] = apply_r_larch_add_sub, +}; + +int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, + unsigned int symindex, unsigned int relsec, + struct module *mod) +{ + int i, err; + unsigned int type; + s64 rela_stack[RELA_STACK_DEPTH]; + size_t rela_stack_top = 0; + reloc_rela_handler handler; + void *location; + Elf_Addr v; + Elf_Sym *sym; + Elf_Rela *rel = (void *) sechdrs[relsec].sh_addr; + + pr_debug("%s: Applying relocate section %u to %u\n", __func__, relsec, + sechdrs[relsec].sh_info); + + rela_stack_top = 0; + for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { + /* This is where to make the change */ + location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr + rel[i].r_offset; + /* This is the symbol it is referring to */ + sym = (Elf_Sym *)sechdrs[symindex].sh_addr + ELF_R_SYM(rel[i].r_info); + if (IS_ERR_VALUE(sym->st_value)) { + /* Ignore unresolved weak symbol */ + if (ELF_ST_BIND(sym->st_info) == STB_WEAK) + continue; + pr_warn("%s: Unknown symbol %s\n", mod->name, strtab + sym->st_name); + return -ENOENT; + } + + type = ELF_R_TYPE(rel[i].r_info); + + if (type < ARRAY_SIZE(reloc_rela_handlers)) + handler = reloc_rela_handlers[type]; + else + handler = NULL; + + if (!handler) { + pr_err("%s: Unknown relocation type %u\n", mod->name, type); + return -EINVAL; + } + + pr_debug("type %d st_value %llx r_addend %llx loc %llx\n", + (int)ELF_R_TYPE(rel[i].r_info), + sym->st_value, rel[i].r_addend, (u64)location); + + v = sym->st_value + rel[i].r_addend; + err = handler(mod, location, v, rela_stack, &rela_stack_top, type); + if (err) + return err; + } + + return 0; +} + +void *module_alloc(unsigned long size) +{ + return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END, + GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE, __builtin_return_address(0)); +} -- 2.27.0