From 9f85a4bbb1cf56f65b3d065a5f88204a757f2325 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Thu, 5 Aug 2010 12:59:04 -0600 Subject: module: refactor load_module part 4 Allocate references inside module_unload_init(), clean up inside module_unload_free(). This version fixed to do allocation before __this_cpu_write, thanks to bug reports from linux-next from Dave Young and Stephen Rothwell . Signed-off-by: Rusty Russell --- kernel/module.c | 32 +++++++++++++++----------------- 1 file changed, 15 insertions(+), 17 deletions(-) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index d8faf35cba84..241bc41dd6be 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -524,8 +524,12 @@ static char last_unloaded_module[MODULE_NAME_LEN+1]; EXPORT_TRACEPOINT_SYMBOL(module_get); /* Init the unload section of the module. */ -static void module_unload_init(struct module *mod) +static int module_unload_init(struct module *mod) { + mod->refptr = alloc_percpu(struct module_ref); + if (!mod->refptr) + return -ENOMEM; + INIT_LIST_HEAD(&mod->source_list); INIT_LIST_HEAD(&mod->target_list); @@ -533,6 +537,8 @@ static void module_unload_init(struct module *mod) __this_cpu_write(mod->refptr->incs, 1); /* Backwards compatibility macros put refcount during init. */ mod->waiter = current; + + return 0; } /* Does a already use b? */ @@ -612,6 +618,8 @@ static void module_unload_free(struct module *mod) kfree(use); } mutex_unlock(&module_mutex); + + free_percpu(mod->refptr); } #ifdef CONFIG_MODULE_FORCE_UNLOAD @@ -885,8 +893,9 @@ int ref_module(struct module *a, struct module *b) } EXPORT_SYMBOL_GPL(ref_module); -static inline void module_unload_init(struct module *mod) +static inline int module_unload_init(struct module *mod) { + return 0; } #endif /* CONFIG_MODULE_UNLOAD */ @@ -1559,10 +1568,7 @@ static void free_module(struct module *mod) module_free(mod, mod->module_init); kfree(mod->args); percpu_modfree(mod); -#if defined(CONFIG_MODULE_UNLOAD) - if (mod->refptr) - free_percpu(mod->refptr); -#endif + /* Free lock-classes: */ lockdep_free_key_range(mod->module_core, mod->core_size); @@ -2442,15 +2448,10 @@ static noinline struct module *load_module(void __user *umod, goto free_percpu; } -#if defined(CONFIG_MODULE_UNLOAD) - mod->refptr = alloc_percpu(struct module_ref); - if (!mod->refptr) { - err = -ENOMEM; - goto free_init; - } -#endif /* Now we've moved module, initialize linked lists, etc. */ - module_unload_init(mod); + err = module_unload_init(mod); + if (err) + goto free_init; /* Set up license info based on the info section */ set_license(mod, get_modinfo(sechdrs, infoindex, "license")); @@ -2619,10 +2620,7 @@ static noinline struct module *load_module(void __user *umod, cleanup: free_modinfo(mod); module_unload_free(mod); -#if defined(CONFIG_MODULE_UNLOAD) - free_percpu(mod->refptr); free_init: -#endif module_free(mod, mod->module_init); module_free(mod, mod->module_core); /* mod will be freed with core. Don't access it beyond this line! */ -- cgit v1.2.2