CONFIG_SYMBOL_PREFIX: cleanup.

We have CONFIG_SYMBOL_PREFIX, which three archs define to the string
"_".  But Al Viro broke this in "consolidate cond_syscall and
SYSCALL_ALIAS declarations" (in linux-next), and he's not the first to
do so.

Using CONFIG_SYMBOL_PREFIX is awkward, since we usually just want to
prefix it so something.  So various places define helpers which are
defined to nothing if CONFIG_SYMBOL_PREFIX isn't set:

1) include/asm-generic/unistd.h defines __SYMBOL_PREFIX.
2) include/asm-generic/vmlinux.lds.h defines VMLINUX_SYMBOL(sym)
3) include/linux/export.h defines MODULE_SYMBOL_PREFIX.
4) include/linux/kernel.h defines SYMBOL_PREFIX (which differs from #7)
5) kernel/modsign_certificate.S defines ASM_SYMBOL(sym)
6) scripts/modpost.c defines MODULE_SYMBOL_PREFIX
7) scripts/Makefile.lib defines SYMBOL_PREFIX on the commandline if
   CONFIG_SYMBOL_PREFIX is set, so that we have a non-string version
   for pasting.

(arch/h8300/include/asm/linkage.h defines SYMBOL_NAME(), too).

Let's solve this properly:
1) No more generic prefix, just CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX.
2) Make linux/export.h usable from asm.
3) Define VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR().
4) Make everyone use them.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Tested-by: James Hogan <james.hogan@imgtec.com> (metag)
This commit is contained in:
Rusty Russell
2013-03-15 15:04:17 +10:30
parent 4febd95a8a
commit b92021b09d
16 changed files with 57 additions and 88 deletions

View File

@@ -18,14 +18,7 @@
#include "modpost.h"
#include "../../include/generated/autoconf.h"
#include "../../include/linux/license.h"
/* Some toolchains use a `_' prefix for all user symbols. */
#ifdef CONFIG_SYMBOL_PREFIX
#define MODULE_SYMBOL_PREFIX CONFIG_SYMBOL_PREFIX
#else
#define MODULE_SYMBOL_PREFIX ""
#endif
#include "../../include/linux/export.h"
/* Are we using CONFIG_MODVERSIONS? */
int modversions = 0;
@@ -562,7 +555,7 @@ static void parse_elf_finish(struct elf_info *info)
static int ignore_undef_symbol(struct elf_info *info, const char *symname)
{
/* ignore __this_module, it will be resolved shortly */
if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") == 0)
if (strcmp(symname, VMLINUX_SYMBOL_STR(__this_module)) == 0)
return 1;
/* ignore global offset table */
if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
@@ -583,8 +576,8 @@ static int ignore_undef_symbol(struct elf_info *info, const char *symname)
return 0;
}
#define CRC_PFX MODULE_SYMBOL_PREFIX "__crc_"
#define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_"
#define CRC_PFX VMLINUX_SYMBOL_STR(__crc_)
#define KSYMTAB_PFX VMLINUX_SYMBOL_STR(__ksymtab_)
static void handle_modversions(struct module *mod, struct elf_info *info,
Elf_Sym *sym, const char *symname)
@@ -637,14 +630,15 @@ static void handle_modversions(struct module *mod, struct elf_info *info,
}
#endif
if (memcmp(symname, MODULE_SYMBOL_PREFIX,
strlen(MODULE_SYMBOL_PREFIX)) == 0) {
mod->unres =
alloc_symbol(symname +
strlen(MODULE_SYMBOL_PREFIX),
ELF_ST_BIND(sym->st_info) == STB_WEAK,
mod->unres);
}
#ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
if (symname[0] != '_')
break;
else
symname++;
#endif
mod->unres = alloc_symbol(symname,
ELF_ST_BIND(sym->st_info) == STB_WEAK,
mod->unres);
break;
default:
/* All exported symbols */
@@ -652,9 +646,9 @@ static void handle_modversions(struct module *mod, struct elf_info *info,
sym_add_exported(symname + strlen(KSYMTAB_PFX), mod,
export);
}
if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0)
if (strcmp(symname, VMLINUX_SYMBOL_STR(init_module)) == 0)
mod->has_init = 1;
if (strcmp(symname, MODULE_SYMBOL_PREFIX "cleanup_module") == 0)
if (strcmp(symname, VMLINUX_SYMBOL_STR(cleanup_module)) == 0)
mod->has_cleanup = 1;
break;
}