Commit 3f63ac8d authored by Huacai Chen's avatar Huacai Chen
Browse files

LoongArch: Adjust module loader for 32BIT/64BIT 



Adjust module loader for both 32BIT and 64BIT, including: change the s64
type to long, change the u64 type to unsigned long, change the plt entry
definition and handling, etc.

Reviewed-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarJiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: default avatarHuacai Chen <chenhuacai@loongson.cn>
parent ced7814d

arch/loongarch/include/asm/module.h

+11 −0
Original line number Diff line number Diff line
@@ -38,8 +38,10 @@ struct got_entry { 


struct plt_entry {

	u32 inst_lu12iw;

#ifdef CONFIG_64BIT

	u32 inst_lu32id;

	u32 inst_lu52id;

#endif

	u32 inst_jirl;

};
@@ -57,6 +59,14 @@ static inline struct got_entry emit_got_entry(Elf_Addr val) 


static inline struct plt_entry emit_plt_entry(unsigned long val)

{

#ifdef CONFIG_32BIT

	u32 lu12iw, jirl;



	lu12iw = larch_insn_gen_lu12iw(LOONGARCH_GPR_T1, ADDR_IMM(val, LU12IW));

	jirl = larch_insn_gen_jirl(0, LOONGARCH_GPR_T1, ADDR_IMM(val, ORI));



	return (struct plt_entry) { lu12iw, jirl };

#else

	u32 lu12iw, lu32id, lu52id, jirl;



	lu12iw = larch_insn_gen_lu12iw(LOONGARCH_GPR_T1, ADDR_IMM(val, LU12IW));
@@ -65,6 +75,7 @@ static inline struct plt_entry emit_plt_entry(unsigned long val) 
	jirl = larch_insn_gen_jirl(0, LOONGARCH_GPR_T1, ADDR_IMM(val, ORI));



	return (struct plt_entry) { lu12iw, lu32id, lu52id, jirl };

#endif

}



static inline struct plt_idx_entry emit_plt_idx_entry(unsigned long val)

arch/loongarch/include/asm/percpu.h

+1 −1
Original line number Diff line number Diff line
@@ -13,7 +13,7 @@ 
 * the loading address of main kernel image, but far from where the modules are

 * loaded. Tell the compiler this fact when using explicit relocs.

 */

#if defined(MODULE) && defined(CONFIG_AS_HAS_EXPLICIT_RELOCS)

#if defined(MODULE) && defined(CONFIG_AS_HAS_EXPLICIT_RELOCS) && defined(CONFIG_64BIT)

# if __has_attribute(model)

#  define PER_CPU_ATTRIBUTES __attribute__((model("extreme")))

# else

arch/loongarch/kernel/module-sections.c

+1 −0
Original line number Diff line number Diff line
@@ -93,6 +93,7 @@ static void count_max_entries(Elf_Rela *relas, int num, 
			(*plts)++;

			break;

		case R_LARCH_GOT_PC_HI20:

		case R_LARCH_GOT_PCADD_HI20:

			(*gots)++;

			break;

		default:

arch/loongarch/kernel/module.c

+150 −54
Original line number Diff line number Diff line
@@ -22,72 +22,89 @@ 
#include <asm/inst.h>

#include <asm/unwind.h>



static int rela_stack_push(s64 stack_value, s64 *rela_stack, size_t *rela_stack_top)

/*

 * reloc_rela_handler() - 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,

			long *rela_stack, size_t *rela_stack_top, unsigned int type);



static int rela_stack_push(long stack_value, long *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);

	pr_debug("%s stack_value = 0x%lx\n", __func__, stack_value);



	return 0;

}



static int rela_stack_pop(s64 *stack_value, s64 *rela_stack, size_t *rela_stack_top)

static int rela_stack_pop(long *stack_value, long *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);

	pr_debug("%s stack_value = 0x%lx\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)

			long *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)

			long *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)

			long *rela_stack, size_t *rela_stack_top, unsigned int type)

{

	*location = v;

	return 0;

}



#ifdef CONFIG_32BIT

#define apply_r_larch_64 apply_r_larch_error

#else

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)

			long *rela_stack, size_t *rela_stack_top, unsigned int type)

{

	*(Elf_Addr *)location = v;

	return 0;

}

#endif



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)

			long *rela_stack, size_t *rela_stack_top, unsigned int type)

{

	return rela_stack_push(v - (u64)location, rela_stack, rela_stack_top);

	return rela_stack_push(v - (unsigned long)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)

			long *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)

			long *rela_stack, size_t *rela_stack_top, unsigned int type)

{

	int err = 0;

	s64 opr1;

	long opr1;



	err = rela_stack_pop(&opr1, rela_stack, rela_stack_top);

	if (err)
@@ -104,7 +121,7 @@ static int apply_r_larch_sop_push_dup(struct module *mod, u32 *location, Elf_Add 


static int apply_r_larch_sop_push_plt_pcrel(struct module *mod,

			Elf_Shdr *sechdrs, u32 *location, Elf_Addr v,

			s64 *rela_stack, size_t *rela_stack_top, unsigned int type)

			long *rela_stack, size_t *rela_stack_top, unsigned int type)

{

	ptrdiff_t offset = (void *)v - (void *)location;
@@ -118,10 +135,10 @@ static int apply_r_larch_sop_push_plt_pcrel(struct module *mod, 
}



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)

			long *rela_stack, size_t *rela_stack_top, unsigned int type)

{

	int err = 0;

	s64 opr1, opr2, opr3;

	long opr1, opr2, opr3;



	if (type == R_LARCH_SOP_IF_ELSE) {

		err = rela_stack_pop(&opr3, rela_stack, rela_stack_top);
@@ -164,10 +181,10 @@ static int apply_r_larch_sop(struct module *mod, u32 *location, Elf_Addr v, 
}



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)

			long *rela_stack, size_t *rela_stack_top, unsigned int type)

{

	int err = 0;

	s64 opr1;

	long opr1;

	union loongarch_instruction *insn = (union loongarch_instruction *)location;



	err = rela_stack_pop(&opr1, rela_stack, rela_stack_top);
@@ -244,31 +261,33 @@ static int apply_r_larch_sop_imm_field(struct module *mod, u32 *location, Elf_Ad 
	}



overflow:

	pr_err("module %s: opr1 = 0x%llx overflow! dangerous %s (%u) relocation\n",

	pr_err("module %s: opr1 = 0x%lx 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",

	pr_err("module %s: opr1 = 0x%lx 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)

			long *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;

#ifdef CONFIG_64BIT

	case R_LARCH_ADD64:

		*(s64 *)location += v;

		return 0;

	case R_LARCH_SUB64:

		*(s64 *)location -= v;

#endif

		return 0;

	default:

		pr_err("%s: Unsupport relocation type %u\n", mod->name, type);
@@ -278,7 +297,7 @@ static int apply_r_larch_add_sub(struct module *mod, u32 *location, Elf_Addr v, 


static int apply_r_larch_b26(struct module *mod,

			Elf_Shdr *sechdrs, u32 *location, Elf_Addr v,

			s64 *rela_stack, size_t *rela_stack_top, unsigned int type)

			long *rela_stack, size_t *rela_stack_top, unsigned int type)

{

	ptrdiff_t offset = (void *)v - (void *)location;

	union loongarch_instruction *insn = (union loongarch_instruction *)location;
@@ -310,15 +329,40 @@ static int apply_r_larch_b26(struct module *mod, 
	return 0;

}



static int apply_r_larch_pcadd(struct module *mod, u32 *location, Elf_Addr v,

			long *rela_stack, size_t *rela_stack_top, unsigned int type)

{

	union loongarch_instruction *insn = (union loongarch_instruction *)location;

	/* Use s32 for a sign-extension deliberately. */

	s32 offset_hi20 = (void *)((v + 0x800)) - (void *)((Elf_Addr)location);



	switch (type) {

	case R_LARCH_PCADD_LO12:

		insn->reg2i12_format.immediate = v & 0xfff;

		break;

	case R_LARCH_PCADD_HI20:

		v = offset_hi20 >> 12;

		insn->reg1i20_format.immediate = v & 0xfffff;

		break;

	default:

		pr_err("%s: Unsupport relocation type %u\n", mod->name, type);

		return -EINVAL;

	}



	return 0;

}



static int apply_r_larch_pcala(struct module *mod, u32 *location, Elf_Addr v,

			s64 *rela_stack, size_t *rela_stack_top, unsigned int type)

			long *rela_stack, size_t *rela_stack_top, unsigned int type)

{

	union loongarch_instruction *insn = (union loongarch_instruction *)location;

	/* Use s32 for a sign-extension deliberately. */

	s32 offset_hi20 = (void *)((v + 0x800) & ~0xfff) -

			  (void *)((Elf_Addr)location & ~0xfff);

#ifdef CONFIG_64BIT

	Elf_Addr anchor = (((Elf_Addr)location) & ~0xfff) + offset_hi20;

	ptrdiff_t offset_rem = (void *)v - (void *)anchor;

#endif



	switch (type) {

	case R_LARCH_PCALA_LO12:
@@ -328,6 +372,7 @@ static int apply_r_larch_pcala(struct module *mod, u32 *location, Elf_Addr v, 
		v = offset_hi20 >> 12;

		insn->reg1i20_format.immediate = v & 0xfffff;

		break;

#ifdef CONFIG_64BIT

	case R_LARCH_PCALA64_LO20:

		v = offset_rem >> 32;

		insn->reg1i20_format.immediate = v & 0xfffff;
@@ -336,6 +381,7 @@ static int apply_r_larch_pcala(struct module *mod, u32 *location, Elf_Addr v, 
		v = offset_rem >> 52;

		insn->reg2i12_format.immediate = v & 0xfff;

		break;

#endif

	default:

		pr_err("%s: Unsupport relocation type %u\n", mod->name, type);

		return -EINVAL;
@@ -346,30 +392,43 @@ static int apply_r_larch_pcala(struct module *mod, u32 *location, Elf_Addr v, 


static int apply_r_larch_got_pc(struct module *mod,

			Elf_Shdr *sechdrs, u32 *location, Elf_Addr v,

			s64 *rela_stack, size_t *rela_stack_top, unsigned int type)

			long *rela_stack, size_t *rela_stack_top, unsigned int type)

{

	Elf_Addr got = module_emit_got_entry(mod, sechdrs, v);

	reloc_rela_handler got_handler;



	if (!got)

	if (type != R_LARCH_GOT_PCADD_LO12) {

		v = module_emit_got_entry(mod, sechdrs, v);

		if (!v)

			return -EINVAL;

	}



	switch (type) {

	case R_LARCH_GOT_PC_LO12:

		type = R_LARCH_PCALA_LO12;

		got_handler = apply_r_larch_pcala;

		break;

	case R_LARCH_GOT_PC_HI20:

		type = R_LARCH_PCALA_HI20;

		got_handler = apply_r_larch_pcala;

		break;

	case R_LARCH_GOT_PCADD_LO12:

		type = R_LARCH_PCADD_LO12;

		got_handler = apply_r_larch_pcadd;

		break;

	case R_LARCH_GOT_PCADD_HI20:

		type = R_LARCH_PCADD_HI20;

		got_handler = apply_r_larch_pcadd;

		break;

	default:

		pr_err("%s: Unsupport relocation type %u\n", mod->name, type);

		return -EINVAL;

	}



	return apply_r_larch_pcala(mod, location, got, rela_stack, rela_stack_top, type);

	return got_handler(mod, location, v, rela_stack, rela_stack_top, type);

}



static int apply_r_larch_32_pcrel(struct module *mod, u32 *location, Elf_Addr v,

				  s64 *rela_stack, size_t *rela_stack_top, unsigned int type)

				  long *rela_stack, size_t *rela_stack_top, unsigned int type)

{

	ptrdiff_t offset = (void *)v - (void *)location;
@@ -377,31 +436,22 @@ static int apply_r_larch_32_pcrel(struct module *mod, u32 *location, Elf_Addr v, 
	return 0;

}



#ifdef CONFIG_32BIT

#define apply_r_larch_64_pcrel apply_r_larch_error

#else

static int apply_r_larch_64_pcrel(struct module *mod, u32 *location, Elf_Addr v,

				  s64 *rela_stack, size_t *rela_stack_top, unsigned int type)

				  long *rela_stack, size_t *rela_stack_top, unsigned int type)

{

	ptrdiff_t offset = (void *)v - (void *)location;



	*(u64 *)location = offset;

	return 0;

}



/*

 * 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);

#endif



/* The handlers for known reloc types */

static reloc_rela_handler reloc_rela_handlers[] = {

	[R_LARCH_NONE ... R_LARCH_64_PCREL]		     = apply_r_larch_error,

	[R_LARCH_NONE ... R_LARCH_TLS_DESC_PCADD_LO12]	     = apply_r_larch_error,



	[R_LARCH_NONE]					     = apply_r_larch_none,

	[R_LARCH_32]					     = apply_r_larch_32,
@@ -414,6 +464,7 @@ static reloc_rela_handler reloc_rela_handlers[] = { 
	[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,

	[R_LARCH_PCADD_HI20 ... R_LARCH_PCADD_LO12]	     = apply_r_larch_pcadd,

	[R_LARCH_PCALA_HI20 ... R_LARCH_PCALA64_HI12]	     = apply_r_larch_pcala,

	[R_LARCH_32_PCREL]				     = apply_r_larch_32_pcrel,

	[R_LARCH_64_PCREL]				     = apply_r_larch_64_pcrel,
@@ -423,9 +474,10 @@ 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];

	int err;

	unsigned int i, idx, type;

	unsigned int num_relocations;

	long rela_stack[RELA_STACK_DEPTH];

	size_t rela_stack_top = 0;

	reloc_rela_handler handler;

	void *location;
@@ -436,8 +488,10 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, 
	pr_debug("%s: Applying relocate section %u to %u\n", __func__, relsec,

	       sechdrs[relsec].sh_info);



	idx = 0;

	rela_stack_top = 0;

	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {

	num_relocations = sechdrs[relsec].sh_size / sizeof(*rel);

	for (i = 0; i < num_relocations; 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 */
@@ -462,17 +516,59 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, 
			return -EINVAL;

		}



		pr_debug("type %d st_value %llx r_addend %llx loc %llx\n",

		pr_debug("type %d st_value %lx r_addend %lx loc %lx\n",

		       (int)ELF_R_TYPE(rel[i].r_info),

		       sym->st_value, rel[i].r_addend, (u64)location);

		       (unsigned long)sym->st_value, (unsigned long)rel[i].r_addend, (unsigned long)location);



		v = sym->st_value + rel[i].r_addend;



		if (type == R_LARCH_PCADD_LO12 || type == R_LARCH_GOT_PCADD_LO12) {

			bool found = false;

			unsigned int j = idx;



			do {

				u32 hi20_type = ELF_R_TYPE(rel[j].r_info);

				unsigned long hi20_location =

					sechdrs[sechdrs[relsec].sh_info].sh_addr + rel[j].r_offset;



				/* Find the corresponding HI20 relocation entry */

				if ((hi20_location == sym->st_value) && (hi20_type == type - 1)) {

					s32 hi20, lo12;

					Elf_Sym *hi20_sym =

						(Elf_Sym *)sechdrs[symindex].sh_addr + ELF_R_SYM(rel[j].r_info);

					unsigned long hi20_sym_val = hi20_sym->st_value + rel[j].r_addend;



					/* Calculate LO12 offset */

					size_t offset = hi20_sym_val - hi20_location;

					if (hi20_type == R_LARCH_GOT_PCADD_HI20) {

						offset = module_emit_got_entry(mod, sechdrs, hi20_sym_val);

						offset = offset - hi20_location;

					}

					hi20 = (offset + 0x800) & 0xfffff000;

					v = lo12 = offset - hi20;

					found = true;

					break;

				}



				j = (j + 1) % num_relocations;



			} while (idx != j);



			if (!found) {

				pr_err("%s: Can not find HI20 relocation information\n", mod->name);

				return -EINVAL;

			}



			idx = j; /* Record the previous j-loop end index */

		}



		switch (type) {

		case R_LARCH_B26:

			err = apply_r_larch_b26(mod, sechdrs, location,

						     v, rela_stack, &rela_stack_top, type);

			break;

		case R_LARCH_GOT_PC_HI20...R_LARCH_GOT_PC_LO12:

		case R_LARCH_GOT_PCADD_HI20...R_LARCH_GOT_PCADD_LO12:

			err = apply_r_larch_got_pc(mod, sechdrs, location,

						     v, rela_stack, &rela_stack_top, type);

			break;