[PATCH] Clean up module.c symbol searching logic

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 41 insertions, 32 deletions

diff --git a/kernel/module.c b/kernel/module.c
index 5aad477ddc79..2a892b20d68f 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -135,6 +135,18 @@ extern const unsigned long __start___kcrctab_gpl[];
 #define symversion(base, idx) ((base) ? ((base) + (idx)) : NULL)
 #endif
 
+/* lookup symbol in given range of kernel_symbols */
+static const struct kernel_symbol *lookup_symbol(const char *name,
+        const struct kernel_symbol *start,
+        const struct kernel_symbol *stop)
+{
+        const struct kernel_symbol *ks = start;
+        for (; ks < stop; ks++)
+                if (strcmp(ks->name, name) == 0)
+                        return ks;
+        return NULL;
+}
+
 /* Find a symbol, return value, crc and module which owns it */
 static unsigned long __find_symbol(const char *name,
                                    struct module **owner,
@@ -142,39 +154,41 @@ static unsigned long __find_symbol(const char *name,
                                    int gplok)
 {
         struct module *mod;
-        unsigned int i;
+        const struct kernel_symbol *ks;
 
         /* Core kernel first. */ 
         *owner = NULL;
-        for (i = 0; __start___ksymtab+i < __stop___ksymtab; i++) {
-                if (strcmp(__start___ksymtab[i].name, name) == 0) {
-                        *crc = symversion(__start___kcrctab, i);
-                        return __start___ksymtab[i].value;
-                }
+        ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
+        if (ks) {
+                *crc = symversion(__start___kcrctab, (ks - __start___ksymtab));
+                return ks->value;
         }
         if (gplok) {
-                for (i = 0; __start___ksymtab_gpl+i<__stop___ksymtab_gpl; i++)
-                        if (strcmp(__start___ksymtab_gpl[i].name, name) == 0) {
-                                *crc = symversion(__start___kcrctab_gpl, i);
-                                return __start___ksymtab_gpl[i].value;
-                        }
+                ks = lookup_symbol(name, __start___ksymtab_gpl,
+                                         __stop___ksymtab_gpl);
+                if (ks) {
+                        *crc = symversion(__start___kcrctab_gpl,
+                                          (ks - __start___ksymtab_gpl));
+                        return ks->value;
+                }
         }
 
         /* Now try modules. */ 
         list_for_each_entry(mod, &modules, list) {
                 *owner = mod;
-                for (i = 0; i < mod->num_syms; i++)
-                        if (strcmp(mod->syms[i].name, name) == 0) {
-                                *crc = symversion(mod->crcs, i);
-                                return mod->syms[i].value;
-                        }
+                ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
+                if (ks) {
+                        *crc = symversion(mod->crcs, (ks - mod->syms));
+                        return ks->value;
+                }
 
                 if (gplok) {
-                        for (i = 0; i < mod->num_gpl_syms; i++) {
-                                if (strcmp(mod->gpl_syms[i].name, name) == 0) {
-                                        *crc = symversion(mod->gpl_crcs, i);
-                                        return mod->gpl_syms[i].value;
-                                }
+                        ks = lookup_symbol(name, mod->gpl_syms,
+                                           mod->gpl_syms + mod->num_gpl_syms);
+                        if (ks) {
+                                *crc = symversion(mod->gpl_crcs,
+                                                  (ks - mod->gpl_syms));
+                                return ks->value;
                         }
                 }
         }
@@ -1444,18 +1458,13 @@ static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
 #ifdef CONFIG_KALLSYMS
 int is_exported(const char *name, const struct module *mod)
 {
-        unsigned int i;
-
-        if (!mod) {
-                for (i = 0; __start___ksymtab+i < __stop___ksymtab; i++)
-                        if (strcmp(__start___ksymtab[i].name, name) == 0)
-                                return 1;
-                return 0;
-        }
-        for (i = 0; i < mod->num_syms; i++)
-                if (strcmp(mod->syms[i].name, name) == 0)
+        if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
+                return 1;
+        else
+                if (lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
                         return 1;
-        return 0;
+                else
+                        return 0;
 }
 
 /* As per nm */