/* Deprecated, do not use. Moved from module.c to here. --RR */ /* Written by Keith Owens <kaos@ocs.com.au> Oct 2000 */ #include <linux/module.h> #include <linux/kmod.h> #include <linux/spinlock.h> #include <linux/list.h> #include <linux/slab.h> /* inter_module functions are always available, even when the kernel is * compiled without modules. Consumers of inter_module_xxx routines * will always work, even when both are built into the kernel, this * approach removes lots of #ifdefs in mainline code. */ static struct list_head ime_list = LIST_HEAD_INIT(ime_list); static DEFINE_SPINLOCK(ime_lock); static int kmalloc_failed; struct inter_module_entry { struct list_head list; const char *im_name; struct module *owner; const void *userdata; }; /** * inter_module_register - register a new set of inter module data. * @im_name: an arbitrary string to identify the data, must be unique * @owner: module that is registering the data, always use THIS_MODULE * @userdata: pointer to arbitrary userdata to be registered * * Description: Check that the im_name has not already been registered, * complain if it has. For new data, add it to the inter_module_entry * list. */ void inter_module_register(const char *im_name, struct module *owner, const void *userdata) { struct list_head *tmp; struct inter_module_entry *ime, *ime_new; if (!(ime_new = kmalloc(sizeof(*ime), GFP_KERNEL))) { /* Overloaded kernel, not fatal */ printk(KERN_ERR "Aiee, inter_module_register: cannot kmalloc entry for '%s'\n", im_name); kmalloc_failed = 1; return; } memset(ime_new, 0, sizeof(*ime_new)); ime_new->im_name = im_name; ime_new->owner = owner; ime_new->userdata = userdata; spin_lock(&ime_lock); list_for_each(tmp, &ime_list) { ime = list_entry(tmp, struct inter_module_entry, list); if (strcmp(ime->im_name, im_name) == 0) { spin_unlock(&ime_lock); kfree(ime_new); /* Program logic error, fatal */ printk(KERN_ERR "inter_module_register: duplicate im_name '%s'", im_name); BUG(); } } list_add(&(ime_new->list), &ime_list); spin_unlock(&ime_lock); } /** * inter_module_unregister - unregister a set of inter module data. * @im_name: an arbitrary string to identify the data, must be unique * * Description: Check that the im_name has been registered, complain if * it has not. For existing data, remove it from the * inter_module_entry list. */ void inter_module_unregister(const char *im_name) { struct list_head *tmp; struct inter_module_entry *ime; spin_lock(&ime_lock); list_for_each(tmp, &ime_list) { ime = list_entry(tmp, struct inter_module_entry, list); if (strcmp(ime->im_name, im_name) == 0) { list_del(&(ime->list)); spin_unlock(&ime_lock); kfree(ime); return; } } spin_unlock(&ime_lock); if (kmalloc_failed) { printk(KERN_ERR "inter_module_unregister: no entry for '%s', " "probably caused by previous kmalloc failure\n", im_name); return; } else { /* Program logic error, fatal */ printk(KERN_ERR "inter_module_unregister: no entry for '%s'", im_name); BUG(); } } /** * inter_module_get - return arbitrary userdata from another module. * @im_name: an arbitrary string to identify the data, must be unique * * Description: If the im_name has not been registered, return NULL. * Try to increment the use count on the owning module, if that fails * then return NULL. Otherwise return the userdata. */ static const void *inter_module_get(const char *im_name) { struct list_head *tmp; struct inter_module_entry *ime; const void *result = NULL; spin_lock(&ime_lock); list_for_each(tmp, &ime_list) { ime = list_entry(tmp, struct inter_module_entry, list); if (strcmp(ime->im_name, im_name) == 0) { if (try_module_get(ime->owner)) result = ime->userdata; break; } } spin_unlock(&ime_lock); return(result); } /** * inter_module_get_request - im get with automatic request_module. * @im_name: an arbitrary string to identify the data, must be unique * @modname: module that is expected to register im_name * * Description: If inter_module_get fails, do request_module then retry. */ const void *inter_module_get_request(const char *im_name, const char *modname) { const void *result = inter_module_get(im_name); if (!result) { request_module("%s", modname); result = inter_module_get(im_name); } return(result); } /** * inter_module_put - release use of data from another module. * @im_name: an arbitrary string to identify the data, must be unique * * Description: If the im_name has not been registered, complain, * otherwise decrement the use count on the owning module. */ void inter_module_put(const char *im_name) { struct list_head *tmp; struct inter_module_entry *ime; spin_lock(&ime_lock); list_for_each(tmp, &ime_list) { ime = list_entry(tmp, struct inter_module_entry, list); if (strcmp(ime->im_name, im_name) == 0) { if (ime->owner) module_put(ime->owner); spin_unlock(&ime_lock); return; } } spin_unlock(&ime_lock); printk(KERN_ERR "inter_module_put: no entry for '%s'", im_name); BUG(); } EXPORT_SYMBOL(inter_module_register); EXPORT_SYMBOL(inter_module_unregister); EXPORT_SYMBOL(inter_module_get_request); EXPORT_SYMBOL(inter_module_put);