Commit bd5cbced authored by Ram Pai's avatar Ram Pai Committed by Sam Ravnborg
Browse files

kbuild: export-type enhancement to modpost.c 



This patch provides the ability to identify the export-type of each
exported symbols in Module.symvers.

NOTE: It updates the Module.symvers file with the additional
information as shown below.

0x0f8b92af      platform_device_add_resources   vmlinux EXPORT_SYMBOL_GPL
0xcf7efb2a      ethtool_op_set_tx_csum          vmlinux EXPORT_SYMBOL

Signed-off-by: default avatarAndreas Gruenbacher <agruen@suse.de>
Signed-off-by: default avatarRam Pai <linuxram@us.ibm.com>
Signed-off-by: default avatarAvantika Mathur <mathur@us.ibm.com>
Signed-off-by: default avatarValdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
parent 031ecc6d

scripts/mod/modpost.c

+77 −16
Original line number Diff line number Diff line
@@ -22,6 +22,8 @@ int have_vmlinux = 0; 
static int all_versions = 0;

/* If we are modposting external module set to 1 */

static int external_module = 0;

/* How a symbol is exported */

enum export {export_plain, export_gpl, export_gpl_future, export_unknown};



void fatal(const char *fmt, ...)

{
@@ -118,6 +120,7 @@ struct symbol { 
	unsigned int kernel:1;     /* 1 if symbol is from kernel

				    *  (only for external modules) **/

	unsigned int preloaded:1;  /* 1 if symbol from Module.symvers */

	enum export  export;       /* Type of export */

	char name[0];

};
@@ -153,7 +156,8 @@ static struct symbol *alloc_symbol(const char *name, unsigned int weak, 
}



/* For the hash of exported symbols */

static struct symbol *new_symbol(const char *name, struct module *module)

static struct symbol *new_symbol(const char *name, struct module *module,

				 enum export export)

{

	unsigned int hash;

	struct symbol *new;
@@ -161,6 +165,7 @@ static struct symbol *new_symbol(const char *name, struct module *module) 
	hash = tdb_hash(name) % SYMBOL_HASH_SIZE;

	new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]);

	new->module = module;

	new->export = export;

	return new;

}
@@ -179,16 +184,55 @@ static struct symbol *find_symbol(const char *name) 
	return NULL;

}



static struct {

	const char *str;

	enum export export;

} export_list[] = {

	{ .str = "EXPORT_SYMBOL",            .export = export_plain },

	{ .str = "EXPORT_SYMBOL_GPL",        .export = export_gpl },

	{ .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future },

	{ .str = "(unknown)",                .export = export_unknown },

};





static const char *export_str(enum export ex)

{

	return export_list[ex].str;

}



static enum export export_no(const char * s)

{

	int i;

	for (i = 0; export_list[i].export != export_unknown; i++) {

		if (strcmp(export_list[i].str, s) == 0)

			return export_list[i].export;

	}

	return export_unknown;

}



static enum export export_from_sec(struct elf_info *elf, Elf_Section sec)

{

	if (sec == elf->export_sec)

		return export_plain;

	else if (sec == elf->export_gpl_sec)

		return export_gpl;

	else if (sec == elf->export_gpl_future_sec)

		return export_gpl_future;

	else

		return export_unknown;

}



/**

 * Add an exported symbol - it may have already been added without a

 * CRC, in this case just update the CRC

 **/

static struct symbol *sym_add_exported(const char *name, struct module *mod)

static struct symbol *sym_add_exported(const char *name, struct module *mod,

				       enum export export)

{

	struct symbol *s = find_symbol(name);



	if (!s) {

		s = new_symbol(name, mod);

		s = new_symbol(name, mod, export);

	} else {

		if (!s->preloaded) {

			warn("%s: '%s' exported twice. Previous export "
@@ -200,16 +244,17 @@ static struct symbol *sym_add_exported(const char *name, struct module *mod) 
	s->preloaded = 0;

	s->vmlinux   = is_vmlinux(mod->name);

	s->kernel    = 0;

	s->export    = export;

	return s;

}



static void sym_update_crc(const char *name, struct module *mod,

			   unsigned int crc)

			   unsigned int crc, enum export export)

{

	struct symbol *s = find_symbol(name);



	if (!s)

		s = new_symbol(name, mod);

		s = new_symbol(name, mod, export);

	s->crc = crc;

	s->crc_valid = 1;

}
@@ -309,13 +354,21 @@ static void parse_elf(struct elf_info *info, const char *filename) 
	for (i = 1; i < hdr->e_shnum; i++) {

		const char *secstrings

			= (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;

		const char *secname;



		if (sechdrs[i].sh_offset > info->size)

			goto truncated;

		if (strcmp(secstrings+sechdrs[i].sh_name, ".modinfo") == 0) {

		secname = secstrings + sechdrs[i].sh_name;

		if (strcmp(secname, ".modinfo") == 0) {

			info->modinfo = (void *)hdr + sechdrs[i].sh_offset;

			info->modinfo_len = sechdrs[i].sh_size;

		}

		} else if (strcmp(secname, "__ksymtab") == 0)

			info->export_sec = i;

		else if (strcmp(secname, "__ksymtab_gpl") == 0)

			info->export_gpl_sec = i;

		else if (strcmp(secname, "__ksymtab_gpl_future") == 0)

			info->export_gpl_future_sec = i;



		if (sechdrs[i].sh_type != SHT_SYMTAB)

			continue;
@@ -353,6 +406,7 @@ static void handle_modversions(struct module *mod, struct elf_info *info, 
			       Elf_Sym *sym, const char *symname)

{

	unsigned int crc;

	enum export export = export_from_sec(info, sym->st_shndx);



	switch (sym->st_shndx) {

	case SHN_COMMON:
@@ -362,7 +416,8 @@ static void handle_modversions(struct module *mod, struct elf_info *info, 
		/* CRC'd symbol */

		if (memcmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) {

			crc = (unsigned int) sym->st_value;

			sym_update_crc(symname + strlen(CRC_PFX), mod, crc);

			sym_update_crc(symname + strlen(CRC_PFX), mod, crc,

					export);

		}

		break;

	case SHN_UNDEF:
@@ -406,7 +461,8 @@ static void handle_modversions(struct module *mod, struct elf_info *info, 
	default:

		/* All exported symbols */

		if (memcmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) {

			sym_add_exported(symname + strlen(KSYMTAB_PFX), mod);

			sym_add_exported(symname + strlen(KSYMTAB_PFX), mod,

					export);

		}

		if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0)

			mod->has_init = 1;
@@ -1146,6 +1202,9 @@ static void write_if_changed(struct buffer *b, const char *fname) 
	fclose(file);

}



/* parse Module.symvers file. line format:

 * 0x12345678<tab>symbol<tab>module[<tab>export]

 **/

static void read_dump(const char *fname, unsigned int kernel)

{

	unsigned long size, pos = 0;
@@ -1157,7 +1216,7 @@ static void read_dump(const char *fname, unsigned int kernel) 
		return;



	while ((line = get_next_line(&pos, file, size))) {

		char *symname, *modname, *d;

		char *symname, *modname, *d, *export;

		unsigned int crc;

		struct module *mod;

		struct symbol *s;
@@ -1168,8 +1227,9 @@ static void read_dump(const char *fname, unsigned int kernel) 
		if (!(modname = strchr(symname, '\t')))

			goto fail;

		*modname++ = '\0';

		if (strchr(modname, '\t'))

			goto fail;

		if (!(export = strchr(modname, '\t')))

			*export++ = '\0';



		crc = strtoul(line, &d, 16);

		if (*symname == '\0' || *modname == '\0' || *d != '\0')

			goto fail;
@@ -1181,10 +1241,10 @@ static void read_dump(const char *fname, unsigned int kernel) 
			mod = new_module(NOFAIL(strdup(modname)));

			mod->skip = 1;

		}

		s = sym_add_exported(symname, mod);

		s = sym_add_exported(symname, mod, export_no(export));

		s->kernel    = kernel;

		s->preloaded = 1;

		sym_update_crc(symname, mod, crc);

		sym_update_crc(symname, mod, crc, export_no(export));

	}

	return;

fail:
@@ -1214,9 +1274,10 @@ static void write_dump(const char *fname) 
		symbol = symbolhash[n];

		while (symbol) {

			if (dump_sym(symbol))

				buf_printf(&buf, "0x%08x\t%s\t%s\n",

				buf_printf(&buf, "0x%08x\t%s\t%s\t%s\n",

					symbol->crc, symbol->name,

					symbol->module->name);

					symbol->module->name,

					export_str(symbol->export));

			symbol = symbol->next;

		}

	}

scripts/mod/modpost.h

+3 −0
Original line number Diff line number Diff line
@@ -115,6 +115,9 @@ struct elf_info { 
	Elf_Shdr     *sechdrs;

	Elf_Sym      *symtab_start;

	Elf_Sym      *symtab_stop;

	Elf_Section  export_sec;

	Elf_Section  export_gpl_sec;

	Elf_Section  export_gpl_future_sec;

	const char   *strtab;

	char	     *modinfo;

	unsigned int modinfo_len;

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