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LoongArch: Add ELF and module support

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Add ELF-related definition and module relocation code for basic
LoongArch support.

Cc: Jessica Yu <jeyu@kernel.org>
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
This commit is contained in:
Huacai Chen 2022-05-31 18:04:11 +08:00
parent b74baf4ad0
commit fcdfe9d22b
12 changed files with 1043 additions and 0 deletions
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24
arch/loongarch/include/asm/cpufeature.h Normal file
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/* 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 */

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arch/loongarch/include/asm/elf.h Normal file
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/* 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 */

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/* 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 */

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arch/loongarch/include/asm/module.h Normal file
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/* 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 */

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arch/loongarch/include/asm/module.lds.h Normal file
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/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (C) 2020-2022 Loongson Technology Corporation Limited */
SECTIONS {
. = ALIGN(4);
.plt : { BYTE(0) }
.plt.idx : { BYTE(0) }
}

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/* 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 */

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arch/loongarch/include/uapi/asm/auxvec.h Normal file
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/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
/*
* Author: Hanlu Li <lihanlu@loongson.cn>
* Huacai Chen <chenhuacai@loongson.cn>
*
* 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 */

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/* 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 */

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// SPDX-License-Identifier: GPL-2.0
/*
* Author: Huacai Chen <chenhuacai@loongson.cn>
* 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;
}

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// 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;
}

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// 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;
}

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// SPDX-License-Identifier: GPL-2.0+
/*
* Author: Hanlu Li <lihanlu@loongson.cn>
* Huacai Chen <chenhuacai@loongson.cn>
*
* 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));
}