diff options
Diffstat (limited to 'include/linux/module.h')
-rw-r--r-- | include/linux/module.h | 147 |
1 files changed, 111 insertions, 36 deletions
diff --git a/include/linux/module.h b/include/linux/module.h index 886d24877c7c..9e56763dff81 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -27,6 +27,7 @@ #include <linux/tracepoint-defs.h> #include <linux/srcu.h> #include <linux/static_call_types.h> +#include <linux/dynamic_debug.h> #include <linux/percpu.h> #include <asm/module.h> @@ -320,17 +321,47 @@ struct mod_tree_node { struct latch_tree_node node; }; -struct module_layout { - /* The actual code + data. */ +enum mod_mem_type { + MOD_TEXT = 0, + MOD_DATA, + MOD_RODATA, + MOD_RO_AFTER_INIT, + MOD_INIT_TEXT, + MOD_INIT_DATA, + MOD_INIT_RODATA, + + MOD_MEM_NUM_TYPES, + MOD_INVALID = -1, +}; + +#define mod_mem_type_is_init(type) \ + ((type) == MOD_INIT_TEXT || \ + (type) == MOD_INIT_DATA || \ + (type) == MOD_INIT_RODATA) + +#define mod_mem_type_is_core(type) (!mod_mem_type_is_init(type)) + +#define mod_mem_type_is_text(type) \ + ((type) == MOD_TEXT || \ + (type) == MOD_INIT_TEXT) + +#define mod_mem_type_is_data(type) (!mod_mem_type_is_text(type)) + +#define mod_mem_type_is_core_data(type) \ + (mod_mem_type_is_core(type) && \ + mod_mem_type_is_data(type)) + +#define for_each_mod_mem_type(type) \ + for (enum mod_mem_type (type) = 0; \ + (type) < MOD_MEM_NUM_TYPES; (type)++) + +#define for_class_mod_mem_type(type, class) \ + for_each_mod_mem_type(type) \ + if (mod_mem_type_is_##class(type)) + +struct module_memory { void *base; - /* Total size. */ unsigned int size; - /* The size of the executable code. */ - unsigned int text_size; - /* Size of RO section of the module (text+rodata) */ - unsigned int ro_size; - /* Size of RO after init section */ - unsigned int ro_after_init_size; #ifdef CONFIG_MODULES_TREE_LOOKUP struct mod_tree_node mtn; @@ -339,9 +370,9 @@ struct module_layout { #ifdef CONFIG_MODULES_TREE_LOOKUP /* Only touch one cacheline for common rbtree-for-core-layout case. */ -#define __module_layout_align ____cacheline_aligned +#define __module_memory_align ____cacheline_aligned #else -#define __module_layout_align +#define __module_memory_align #endif struct mod_kallsyms { @@ -353,9 +384,9 @@ struct mod_kallsyms { #ifdef CONFIG_LIVEPATCH /** - * struct klp_modinfo - Elf information preserved from the livepatch module + * struct klp_modinfo - ELF information preserved from the livepatch module * - * @hdr: Elf header + * @hdr: ELF header * @sechdrs: Section header table * @secstrings: String table for the section headers * @symndx: The symbol table section index @@ -426,12 +457,7 @@ struct module { /* Startup function. */ int (*init)(void); - /* Core layout: rbtree is accessed frequently, so keep together. */ - struct module_layout core_layout __module_layout_align; - struct module_layout init_layout; -#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC - struct module_layout data_layout; -#endif + struct module_memory mem[MOD_MEM_NUM_TYPES] __module_memory_align; /* Arch-specific module values */ struct mod_arch_specific arch; @@ -523,7 +549,7 @@ struct module { bool klp; /* Is this a livepatch module? */ bool klp_alive; - /* Elf information */ + /* ELF information */ struct klp_modinfo *klp_info; #endif @@ -554,6 +580,9 @@ struct module { struct error_injection_entry *ei_funcs; unsigned int num_ei_funcs; #endif +#ifdef CONFIG_DYNAMIC_DEBUG_CORE + struct _ddebug_info dyndbg_info; +#endif } ____cacheline_aligned __randomize_layout; #ifndef MODULE_ARCH_INIT #define MODULE_ARCH_INIT {} @@ -581,23 +610,35 @@ bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr); bool is_module_percpu_address(unsigned long addr); bool is_module_text_address(unsigned long addr); +static inline bool within_module_mem_type(unsigned long addr, + const struct module *mod, + enum mod_mem_type type) +{ + unsigned long base, size; + + base = (unsigned long)mod->mem[type].base; + size = mod->mem[type].size; + return addr - base < size; +} + static inline bool within_module_core(unsigned long addr, const struct module *mod) { -#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC - if ((unsigned long)mod->data_layout.base <= addr && - addr < (unsigned long)mod->data_layout.base + mod->data_layout.size) - return true; -#endif - return (unsigned long)mod->core_layout.base <= addr && - addr < (unsigned long)mod->core_layout.base + mod->core_layout.size; + for_class_mod_mem_type(type, core) { + if (within_module_mem_type(addr, mod, type)) + return true; + } + return false; } static inline bool within_module_init(unsigned long addr, const struct module *mod) { - return (unsigned long)mod->init_layout.base <= addr && - addr < (unsigned long)mod->init_layout.base + mod->init_layout.size; + for_class_mod_mem_type(type, init) { + if (within_module_mem_type(addr, mod, type)) + return true; + } + return false; } static inline bool within_module(unsigned long addr, const struct module *mod) @@ -622,10 +663,46 @@ void symbol_put_addr(void *addr); to handle the error case (which only happens with rmmod --wait). */ extern void __module_get(struct module *module); -/* This is the Right Way to get a module: if it fails, it's being removed, - * so pretend it's not there. */ +/** + * try_module_get() - take module refcount unless module is being removed + * @module: the module we should check for + * + * Only try to get a module reference count if the module is not being removed. + * This call will fail if the module is already being removed. + * + * Care must also be taken to ensure the module exists and is alive prior to + * usage of this call. This can be gauranteed through two means: + * + * 1) Direct protection: you know an earlier caller must have increased the + * module reference through __module_get(). This can typically be achieved + * by having another entity other than the module itself increment the + * module reference count. + * + * 2) Implied protection: there is an implied protection against module + * removal. An example of this is the implied protection used by kernfs / + * sysfs. The sysfs store / read file operations are guaranteed to exist + * through the use of kernfs's active reference (see kernfs_active()) and a + * sysfs / kernfs file removal cannot happen unless the same file is not + * active. Therefore, if a sysfs file is being read or written to the module + * which created it must still exist. It is therefore safe to use + * try_module_get() on module sysfs store / read ops. + * + * One of the real values to try_module_get() is the module_is_live() check + * which ensures that the caller of try_module_get() can yield to userspace + * module removal requests and gracefully fail if the module is on its way out. + * + * Returns true if the reference count was successfully incremented. + */ extern bool try_module_get(struct module *module); +/** + * module_put() - release a reference count to a module + * @module: the module we should release a reference count for + * + * If you successfully bump a reference count to a module with try_module_get(), + * when you are finished you must call module_put() to release that reference + * count. + */ extern void module_put(struct module *module); #else /*!CONFIG_MODULE_UNLOAD*/ @@ -782,7 +859,7 @@ void *dereference_module_function_descriptor(struct module *mod, void *ptr) #ifdef CONFIG_SYSFS extern struct kset *module_kset; -extern struct kobj_type module_ktype; +extern const struct kobj_type module_ktype; #endif /* CONFIG_SYSFS */ #define symbol_request(x) try_then_request_module(symbol_get(x), "symbol:" #x) @@ -836,8 +913,7 @@ static inline bool module_sig_ok(struct module *module) #if defined(CONFIG_MODULES) && defined(CONFIG_KALLSYMS) int module_kallsyms_on_each_symbol(const char *modname, - int (*fn)(void *, const char *, - struct module *, unsigned long), + int (*fn)(void *, const char *, unsigned long), void *data); /* For kallsyms to ask for address resolution. namebuf should be at @@ -870,8 +946,7 @@ unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name); #else /* CONFIG_MODULES && CONFIG_KALLSYMS */ static inline int module_kallsyms_on_each_symbol(const char *modname, - int (*fn)(void *, const char *, - struct module *, unsigned long), + int (*fn)(void *, const char *, unsigned long), void *data) { return -EOPNOTSUPP; |