module: Export symbols needed for Ksplice

Impact: Expose some module.c symbols

Ksplice uses several functions from module.c in order to resolve
symbols and implement dependency handling.  Calling these functions
requires holding module_mutex, so it is exported.

(This is just the module part of a bigger add-exports patch from Tim).

Cc: Anders Kaseorg <andersk@mit.edu>
Cc: Jeff Arnold <jbarnold@mit.edu>
Signed-off-by: Tim Abbott <tabbott@mit.edu>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

1 files changed, 28 insertions, 0 deletions

diff --git a/include/linux/module.h b/include/linux/module.h
index c3d3fc4ffb1..d246da0b0f8 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -354,6 +354,8 @@ struct module
 #define MODULE_ARCH_INIT {}
 #endif
 
+extern struct mutex module_mutex;
+
 /* FIXME: It'd be nice to isolate modules during init, too, so they
    aren't used before they (may) fail.  But presently too much code
    (IDE & SCSI) require entry into the module during init.*/
@@ -379,6 +381,31 @@ static inline int within_module_init(unsigned long addr, struct module *mod)
                addr < (unsigned long)mod->module_init + mod->init_size;
 }
 
+/* Search for module by name: must hold module_mutex. */
+struct module *find_module(const char *name);
+
+struct symsearch {
+        const struct kernel_symbol *start, *stop;
+        const unsigned long *crcs;
+        enum {
+                NOT_GPL_ONLY,
+                GPL_ONLY,
+                WILL_BE_GPL_ONLY,
+        } licence;
+        bool unused;
+};
+
+/* Search for an exported symbol by name. */
+const struct kernel_symbol *find_symbol(const char *name,
+                                        struct module **owner,
+                                        const unsigned long **crc,
+                                        bool gplok,
+                                        bool warn);
+
+/* Walk the exported symbol table */
+bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
+                            unsigned int symnum, void *data), void *data);
+
 /* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
    symnum out of range. */
 int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
@@ -452,6 +479,7 @@ static inline void __module_get(struct module *module)
 #define symbol_put_addr(p) do { } while(0)
 
 #endif /* CONFIG_MODULE_UNLOAD */
+int use_module(struct module *a, struct module *b);
 
 /* This is a #define so the string doesn't get put in every .o file */
 #define module_name(mod)                        \