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kbuild: export-type enhancement to modpost.c
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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: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Avantika Mathur <mathur@us.ibm.com>
Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
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Ram Pai authored and Sam Ravnborg committed Jun 9, 2006
1 parent 031ecc6 commit bd5cbce
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Showing 2 changed files with 80 additions and 16 deletions.
93 changes: 77 additions & 16 deletions scripts/mod/modpost.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -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, ...)
{
Expand Down Expand Up @@ -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];
};

Expand Down Expand Up @@ -153,14 +156,16 @@ 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;

hash = tdb_hash(name) % SYMBOL_HASH_SIZE;
new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]);
new->module = module;
new->export = export;
return new;
}

Expand All @@ -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 "
Expand All @@ -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;
}
Expand Down Expand Up @@ -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;

Expand Down Expand Up @@ -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:
Expand All @@ -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:
Expand Down Expand Up @@ -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;
Expand Down Expand Up @@ -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;
Expand All @@ -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;
Expand All @@ -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;
Expand All @@ -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:
Expand Down Expand Up @@ -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;
}
}
Expand Down
3 changes: 3 additions & 0 deletions scripts/mod/modpost.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -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;
Expand Down

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