Simplify kallsyms_lookup()

Several kallsyms_lookup() pass dummy arguments but only need, say, module's
name.  Make kallsyms_lookup() accept NULLs where possible.

Also, makes picture clearer about what interfaces are needed for all symbol
resolving business.

Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 2 deletions

diff --git a/kernel/module.c b/kernel/module.c
index 5ee65994a3bc..bf4dccadf7b8 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2098,8 +2098,10 @@ static const char *get_ksymbol(struct module *mod,
         if (!best)
                 return NULL;
 
-        *size = nextval - mod->symtab[best].st_value;
-        *offset = addr - mod->symtab[best].st_value;
+        if (size)
+                *size = nextval - mod->symtab[best].st_value;
+        if (offset)
+                *offset = addr - mod->symtab[best].st_value;
         return mod->strtab + mod->symtab[best].st_name;
 }