Commit 5b24c071 authored by Sam Ravnborg's avatar Sam Ravnborg
Browse files

kbuild: code refactoring in modpost 



Split a too long function up in smaller bits to make
prgram logic easier to follow.
A few related changes done due to parameter
changes.

No functional changes.

Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
parent 9ad21c3f

scripts/mod/modpost.c

+137 −105
Original line number Diff line number Diff line
@@ -937,19 +937,19 @@ static void warn_sec_mismatch(const char *modname, const char *fromsec, 
}



static unsigned int *reloc_location(struct elf_info *elf,

					   int rsection, Elf_Rela *r)

				    Elf_Shdr *sechdr, Elf_Rela *r)

{

	Elf_Shdr *sechdrs = elf->sechdrs;

	int section = sechdrs[rsection].sh_info;

	int section = sechdr->sh_info;



	return (void *)elf->hdr + sechdrs[section].sh_offset +

		(r->r_offset - sechdrs[section].sh_addr);

}



static int addend_386_rel(struct elf_info *elf, int rsection, Elf_Rela *r)

static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)

{

	unsigned int r_typ = ELF_R_TYPE(r->r_info);

	unsigned int *location = reloc_location(elf, rsection, r);

	unsigned int *location = reloc_location(elf, sechdr, r);



	switch (r_typ) {

	case R_386_32:
@@ -965,7 +965,7 @@ static int addend_386_rel(struct elf_info *elf, int rsection, Elf_Rela *r) 
	return 0;

}



static int addend_arm_rel(struct elf_info *elf, int rsection, Elf_Rela *r)

static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)

{

	unsigned int r_typ = ELF_R_TYPE(r->r_info);
@@ -978,8 +978,8 @@ static int addend_arm_rel(struct elf_info *elf, int rsection, Elf_Rela *r) 
	case R_ARM_PC24:

		/* From ARM ABI: ((S + A) | T) - P */

		r->r_addend = (int)(long)(elf->hdr +

		              elf->sechdrs[rsection].sh_offset +

		              (r->r_offset - elf->sechdrs[rsection].sh_addr));

		              sechdr->sh_offset +

		              (r->r_offset - sechdr->sh_addr));

		break;

	default:

		return 1;
@@ -987,10 +987,10 @@ static int addend_arm_rel(struct elf_info *elf, int rsection, Elf_Rela *r) 
	return 0;

}



static int addend_mips_rel(struct elf_info *elf, int rsection, Elf_Rela *r)

static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)

{

	unsigned int r_typ = ELF_R_TYPE(r->r_info);

	unsigned int *location = reloc_location(elf, rsection, r);

	unsigned int *location = reloc_location(elf, sechdr, r);

	unsigned int inst;



	if (r_typ == R_MIPS_HI16)
@@ -1010,44 +1010,29 @@ static int addend_mips_rel(struct elf_info *elf, int rsection, Elf_Rela *r) 
	return 0;

}



/**

 * A module includes a number of sections that are discarded

 * either when loaded or when used as built-in.

 * For loaded modules all functions marked __init and all data

 * marked __initdata will be discarded when the module has been intialized.

 * Likewise for modules used built-in the sections marked __exit

 * are discarded because __exit marked function are supposed to be called

 * only when a moduel is unloaded which never happes for built-in modules.

 * The check_sec_ref() function traverses all relocation records

 * to find all references to a section that reference a section that will

 * be discarded and warns about it.

 **/

static void check_sec_ref(struct module *mod, const char *modname,

			  struct elf_info *elf,

			  int section(const char *),

static void section_rela(const char *modname, struct elf_info *elf,

                         Elf_Shdr *sechdr, int section(const char *),

                         int section_ref_ok(const char *))

{

	int i;

	Elf_Sym  *sym;

	Elf_Rela *rela;

	Elf_Rela r;

	unsigned int r_sym;

	const char *fromsec;

	const char * tosec;



	Elf_Ehdr *hdr = elf->hdr;

	Elf_Shdr *sechdrs = elf->sechdrs;

	Elf_Rela *start = (void *)hdr + sechdr->sh_offset;

	Elf_Rela *stop  = (void *)start + sechdr->sh_size;



	const char *secstrings = (void *)hdr +

				 sechdrs[hdr->e_shstrndx].sh_offset;

				 elf->sechdrs[hdr->e_shstrndx].sh_offset;



	/* Walk through all sections */

	for (i = 0; i < hdr->e_shnum; i++) {

		const char *name = secstrings + sechdrs[i].sh_name;

		const char *secname;

		Elf_Rela r;

		unsigned int r_sym;

		/* We want to process only relocation sections and not .init */

		if (sechdrs[i].sh_type == SHT_RELA) {

			Elf_Rela *rela;

			Elf_Rela *start = (void *)hdr + sechdrs[i].sh_offset;

			Elf_Rela *stop  = (void *)start + sechdrs[i].sh_size;

			name += strlen(".rela");

			if (section_ref_ok(name))

				continue;

	fromsec = secstrings + sechdr->sh_name;

	fromsec += strlen(".rela");

	/* if from section (name) is know good then skip it */

	if (section_ref_ok(fromsec))

		return;



	for (rela = start; rela < stop; rela++) {

		r.r_offset = TO_NATIVE(rela->r_offset);
@@ -1072,19 +1057,36 @@ static void check_sec_ref(struct module *mod, const char *modname, 
		if (sym->st_shndx >= SHN_LORESERVE)

			continue;



				secname = secstrings +

					sechdrs[sym->st_shndx].sh_name;

				if (section(secname))

					warn_sec_mismatch(modname, name,

							  elf, sym, r);

		tosec = secstrings +

			elf->sechdrs[sym->st_shndx].sh_name;

		if (section(tosec))

			warn_sec_mismatch(modname, fromsec, elf, sym, r);

	}

		} else if (sechdrs[i].sh_type == SHT_REL) {

}



static void section_rel(const char *modname, struct elf_info *elf,

                        Elf_Shdr *sechdr, int section(const char *),

                        int section_ref_ok(const char *))

{

	Elf_Sym *sym;

	Elf_Rel *rel;

			Elf_Rel *start = (void *)hdr + sechdrs[i].sh_offset;

			Elf_Rel *stop  = (void *)start + sechdrs[i].sh_size;

			name += strlen(".rel");

			if (section_ref_ok(name))

				continue;

	Elf_Rela r;

	unsigned int r_sym;

	const char *fromsec;

	const char * tosec;



	Elf_Ehdr *hdr = elf->hdr;

	Elf_Rel *start = (void *)hdr + sechdr->sh_offset;

	Elf_Rel *stop  = (void *)start + sechdr->sh_size;



	const char *secstrings = (void *)hdr +

				 elf->sechdrs[hdr->e_shstrndx].sh_offset;



	fromsec = secstrings + sechdr->sh_name;

	fromsec += strlen(".rel");

	/* if from section (name) is know good then skip it */

	if (section_ref_ok(fromsec))

		return;



	for (rel = start; rel < stop; rel++) {

		r.r_offset = TO_NATIVE(rel->r_offset);
@@ -1106,15 +1108,15 @@ static void check_sec_ref(struct module *mod, const char *modname, 
		r.r_addend = 0;

		switch (hdr->e_machine) {

		case EM_386:

					if (addend_386_rel(elf, i, &r))

			if (addend_386_rel(elf, sechdr, &r))

				continue;

			break;

		case EM_ARM:

					if (addend_arm_rel(elf, i, &r))

			if (addend_arm_rel(elf, sechdr, &r))

				continue;

			break;

		case EM_MIPS:

					if (addend_mips_rel(elf, i, &r))

			if (addend_mips_rel(elf, sechdr, &r))

				continue;

			break;

		}
@@ -1123,13 +1125,43 @@ static void check_sec_ref(struct module *mod, const char *modname, 
		if (sym->st_shndx >= SHN_LORESERVE)

			continue;



				secname = secstrings +

					sechdrs[sym->st_shndx].sh_name;

				if (section(secname))

					warn_sec_mismatch(modname, name,

							  elf, sym, r);

		tosec = secstrings +

			elf->sechdrs[sym->st_shndx].sh_name;

		if (section(tosec))

			warn_sec_mismatch(modname, fromsec, elf, sym, r);

	}

}



/**

 * A module includes a number of sections that are discarded

 * either when loaded or when used as built-in.

 * For loaded modules all functions marked __init and all data

 * marked __initdata will be discarded when the module has been intialized.

 * Likewise for modules used built-in the sections marked __exit

 * are discarded because __exit marked function are supposed to be called

 * only when a moduel is unloaded which never happes for built-in modules.

 * The check_sec_ref() function traverses all relocation records

 * to find all references to a section that reference a section that will

 * be discarded and warns about it.

 **/

static void check_sec_ref(struct module *mod, const char *modname,

			  struct elf_info *elf,

			  int section(const char *),

			  int section_ref_ok(const char *))

{

	int i;

	Elf_Ehdr *hdr = elf->hdr;

	Elf_Shdr *sechdrs = elf->sechdrs;



	/* Walk through all sections */

	for (i = 0; i < hdr->e_shnum; i++) {

		/* We want to process only relocation sections and not .init */

		if (sechdrs[i].sh_type == SHT_RELA)

			section_rela(modname, elf, &elf->sechdrs[i],

			             section, section_ref_ok);

		else if (sechdrs[i].sh_type == SHT_REL)

			section_rel(modname, elf, &elf->sechdrs[i],

			            section, section_ref_ok);

	}

}