From 2c02dfe7fe3fba97a5665d329d039d2415ea5607 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Mon, 31 May 2010 12:19:37 -0700 Subject: module: Make the 'usage' lists be two-way When adding a module that depends on another one, we used to create a one-way list of "modules_which_use_me", so that module unloading could see who needs a module. It's actually quite simple to make that list go both ways: so that we not only can see "who uses me", but also see a list of modules that are "used by me". In fact, we always wanted that list in "module_unload_free()": when we unload a module, we want to also release all the other modules that are used by that module. But because we didn't have that list, we used to first iterate over all modules, and then iterate over each "used by me" list of that module. By making the list two-way, we simplify module_unload_free(), and it allows for some trivial fixes later too. Signed-off-by: Linus Torvalds Signed-off-by: Rusty Russell (cleaned & rebased) --- include/linux/module.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/module.h b/include/linux/module.h index 6914fcad467..680db9e2ac3 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -359,7 +359,9 @@ struct module #ifdef CONFIG_MODULE_UNLOAD /* What modules depend on me? */ - struct list_head modules_which_use_me; + struct list_head source_list; + /* What modules do I depend on? */ + struct list_head target_list; /* Who is waiting for us to be unloaded */ struct task_struct *waiter; -- cgit v1.2.3-70-g09d2 From c8e21ced08b39ef8dfe7236fb2a923a95f645262 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Sat, 5 Jun 2010 11:17:35 -0600 Subject: module: fix kdb's illicit use of struct module_use. Linus changed the structure, and luckily this didn't compile any more. Reported-by: Stephen Rothwell Signed-off-by: Rusty Russell Cc: Jason Wessel Cc: Martin Hicks --- include/linux/module.h | 7 +++++++ kernel/debug/kdb/kdb_main.c | 12 +++--------- kernel/module.c | 11 +---------- 3 files changed, 11 insertions(+), 19 deletions(-) (limited to 'include/linux') diff --git a/include/linux/module.h b/include/linux/module.h index 680db9e2ac3..5d8fca5dcff 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -181,6 +181,13 @@ void *__symbol_get(const char *symbol); void *__symbol_get_gpl(const char *symbol); #define symbol_get(x) ((typeof(&x))(__symbol_get(MODULE_SYMBOL_PREFIX #x))) +/* modules using other modules: kdb wants to see this. */ +struct module_use { + struct list_head source_list; + struct list_head target_list; + struct module *source, *target; +}; + #ifndef __GENKSYMS__ #ifdef CONFIG_MODVERSIONS /* Mark the CRC weak since genksyms apparently decides not to diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index b724c791b6d..184cd8209c3 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -1857,12 +1857,6 @@ static int kdb_ef(int argc, const char **argv) } #if defined(CONFIG_MODULES) -/* modules using other modules */ -struct module_use { - struct list_head list; - struct module *module_which_uses; -}; - /* * kdb_lsmod - This function implements the 'lsmod' command. Lists * currently loaded kernel modules. @@ -1894,9 +1888,9 @@ static int kdb_lsmod(int argc, const char **argv) { struct module_use *use; kdb_printf(" [ "); - list_for_each_entry(use, &mod->modules_which_use_me, - list) - kdb_printf("%s ", use->module_which_uses->name); + list_for_each_entry(use, &mod->source_list, + source_list) + kdb_printf("%s ", use->target->name); kdb_printf("]\n"); } #endif diff --git a/kernel/module.c b/kernel/module.c index be18c3e3468..bbb1d812c79 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -536,14 +536,6 @@ static void module_unload_init(struct module *mod) mod->waiter = current; } -/* modules using other modules */ -struct module_use -{ - struct list_head source_list; - struct list_head target_list; - struct module *source, *target; -}; - /* Does a already use b? */ static int already_uses(struct module *a, struct module *b) { @@ -589,8 +581,7 @@ static int add_module_usage(struct module *a, struct module *b) /* Module a uses b */ int use_module(struct module *a, struct module *b) { - struct module_use *use; - int no_warn, err; + int err; if (b == NULL || already_uses(a, b)) return 1; -- cgit v1.2.3-70-g09d2 From 6407ebb271fc34440b306f305e1efb7685eece26 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Sat, 5 Jun 2010 11:17:36 -0600 Subject: module: Make module sysfs functions private. These were placed in the header in ef665c1a06 to get the various SYSFS/MODULE config combintations to compile. That may have been necessary then, but it's not now. These functions are all local to module.c. Signed-off-by: Rusty Russell Cc: Randy Dunlap --- include/linux/module.h | 33 --------------------------------- kernel/module.c | 29 +++++++++++++++++++++++++---- 2 files changed, 25 insertions(+), 37 deletions(-) (limited to 'include/linux') diff --git a/include/linux/module.h b/include/linux/module.h index 5d8fca5dcff..8a6b9fdc7ff 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -672,43 +672,10 @@ static inline int module_get_iter_tracepoints(struct tracepoint_iter *iter) #endif /* CONFIG_MODULES */ -struct device_driver; #ifdef CONFIG_SYSFS -struct module; - extern struct kset *module_kset; extern struct kobj_type module_ktype; extern int module_sysfs_initialized; - -int mod_sysfs_init(struct module *mod); -int mod_sysfs_setup(struct module *mod, - struct kernel_param *kparam, - unsigned int num_params); -int module_add_modinfo_attrs(struct module *mod); -void module_remove_modinfo_attrs(struct module *mod); - -#else /* !CONFIG_SYSFS */ - -static inline int mod_sysfs_init(struct module *mod) -{ - return 0; -} - -static inline int mod_sysfs_setup(struct module *mod, - struct kernel_param *kparam, - unsigned int num_params) -{ - return 0; -} - -static inline int module_add_modinfo_attrs(struct module *mod) -{ - return 0; -} - -static inline void module_remove_modinfo_attrs(struct module *mod) -{ } - #endif /* CONFIG_SYSFS */ #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x) diff --git a/kernel/module.c b/kernel/module.c index c690d988579..808aa18dd66 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1323,7 +1323,7 @@ static void del_usage_links(struct module *mod) #endif } -int module_add_modinfo_attrs(struct module *mod) +static int module_add_modinfo_attrs(struct module *mod) { struct module_attribute *attr; struct module_attribute *temp_attr; @@ -1349,7 +1349,7 @@ int module_add_modinfo_attrs(struct module *mod) return error; } -void module_remove_modinfo_attrs(struct module *mod) +static void module_remove_modinfo_attrs(struct module *mod) { struct module_attribute *attr; int i; @@ -1365,7 +1365,7 @@ void module_remove_modinfo_attrs(struct module *mod) kfree(mod->modinfo_attrs); } -int mod_sysfs_init(struct module *mod) +static int mod_sysfs_init(struct module *mod) { int err; struct kobject *kobj; @@ -1399,7 +1399,7 @@ out: return err; } -int mod_sysfs_setup(struct module *mod, +static int mod_sysfs_setup(struct module *mod, struct kernel_param *kparam, unsigned int num_params) { @@ -1445,6 +1445,27 @@ static void mod_sysfs_fini(struct module *mod) #else /* CONFIG_SYSFS */ +static inline int mod_sysfs_init(struct module *mod) +{ + return 0; +} + +static inline int mod_sysfs_setup(struct module *mod, + struct kernel_param *kparam, + unsigned int num_params) +{ + return 0; +} + +static inline int module_add_modinfo_attrs(struct module *mod) +{ + return 0; +} + +static inline void module_remove_modinfo_attrs(struct module *mod) +{ +} + static void mod_sysfs_fini(struct module *mod) { } -- cgit v1.2.3-70-g09d2