Commit f3227ffd authored by Thomas Weißschuh's avatar Thomas Weißschuh Committed by Petr Pavlu
Browse files

module: Constify 'struct module_attribute' 



These structs are never modified, move them to read-only memory.
This makes the API clearer and also prepares for the constification of
'struct attribute' itself.

While at it, also constify 'modinfo_attrs_count'.

Signed-off-by: default avatarThomas Weißschuh <linux@weissschuh.net>
Reviewed-by: default avatarPetr Pavlu <petr.pavlu@suse.com>
Link: https://lore.kernel.org/r/20241216-sysfs-const-attr-module-v1-3-3790b53e0abf@weissschuh.net


Signed-off-by: default avatarPetr Pavlu <petr.pavlu@suse.com>
parent 38e3fe65

include/linux/module.h

+4 −4
Original line number Diff line number Diff line
@@ -52,9 +52,9 @@ struct module_kobject { 


struct module_attribute {

	struct attribute attr;

	ssize_t (*show)(struct module_attribute *, struct module_kobject *,

	ssize_t (*show)(const struct module_attribute *, struct module_kobject *,

			char *);

	ssize_t (*store)(struct module_attribute *, struct module_kobject *,

	ssize_t (*store)(const struct module_attribute *, struct module_kobject *,

			 const char *, size_t count);

	void (*setup)(struct module *, const char *);

	int (*test)(struct module *);
@@ -67,10 +67,10 @@ struct module_version_attribute { 
	const char *version;

};



extern ssize_t __modver_version_show(struct module_attribute *,

extern ssize_t __modver_version_show(const struct module_attribute *,

				     struct module_kobject *, char *);



extern struct module_attribute module_uevent;

extern const struct module_attribute module_uevent;



/* These are either module local, or the kernel's dummy ones. */

extern int init_module(void);

kernel/module/internal.h

+2 −2
Original line number Diff line number Diff line
@@ -47,8 +47,8 @@ struct kernel_symbol { 
extern struct mutex module_mutex;

extern struct list_head modules;



extern struct module_attribute *modinfo_attrs[];

extern size_t modinfo_attrs_count;

extern const struct module_attribute *const modinfo_attrs[];

extern const size_t modinfo_attrs_count;



/* Provided by the linker */

extern const struct kernel_symbol __start___ksymtab[];

kernel/module/main.c

+20 −20
Original line number Diff line number Diff line
@@ -538,7 +538,7 @@ static void setup_modinfo_##field(struct module *mod, const char *s) \ 
{                                                                     \

	mod->field = kstrdup(s, GFP_KERNEL);                          \

}                                                                     \

static ssize_t show_modinfo_##field(struct module_attribute *mattr,   \

static ssize_t show_modinfo_##field(const struct module_attribute *mattr, \

			struct module_kobject *mk, char *buffer)      \

{                                                                     \

	return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field);  \
@@ -552,7 +552,7 @@ static void free_modinfo_##field(struct module *mod) \ 
	kfree(mod->field);                                            \

	mod->field = NULL;                                            \

}                                                                     \

static struct module_attribute modinfo_##field = {                    \

static const struct module_attribute modinfo_##field = {              \

	.attr = { .name = __stringify(field), .mode = 0444 },         \

	.show = show_modinfo_##field,                                 \

	.setup = setup_modinfo_##field,                               \
@@ -842,13 +842,13 @@ void symbol_put_addr(void *addr) 
}

EXPORT_SYMBOL_GPL(symbol_put_addr);



static ssize_t show_refcnt(struct module_attribute *mattr,

static ssize_t show_refcnt(const struct module_attribute *mattr,

			   struct module_kobject *mk, char *buffer)

{

	return sprintf(buffer, "%i\n", module_refcount(mk->mod));

}



static struct module_attribute modinfo_refcnt =

static const struct module_attribute modinfo_refcnt =

	__ATTR(refcnt, 0444, show_refcnt, NULL);



void __module_get(struct module *module)
@@ -917,7 +917,7 @@ size_t module_flags_taint(unsigned long taints, char *buf) 
	return l;

}



static ssize_t show_initstate(struct module_attribute *mattr,

static ssize_t show_initstate(const struct module_attribute *mattr,

			      struct module_kobject *mk, char *buffer)

{

	const char *state = "unknown";
@@ -938,10 +938,10 @@ static ssize_t show_initstate(struct module_attribute *mattr, 
	return sprintf(buffer, "%s\n", state);

}



static struct module_attribute modinfo_initstate =

static const struct module_attribute modinfo_initstate =

	__ATTR(initstate, 0444, show_initstate, NULL);



static ssize_t store_uevent(struct module_attribute *mattr,

static ssize_t store_uevent(const struct module_attribute *mattr,

			    struct module_kobject *mk,

			    const char *buffer, size_t count)

{
@@ -951,10 +951,10 @@ static ssize_t store_uevent(struct module_attribute *mattr, 
	return rc ? rc : count;

}



struct module_attribute module_uevent =

const struct module_attribute module_uevent =

	__ATTR(uevent, 0200, NULL, store_uevent);



static ssize_t show_coresize(struct module_attribute *mattr,

static ssize_t show_coresize(const struct module_attribute *mattr,

			     struct module_kobject *mk, char *buffer)

{

	unsigned int size = mk->mod->mem[MOD_TEXT].size;
@@ -966,11 +966,11 @@ static ssize_t show_coresize(struct module_attribute *mattr, 
	return sprintf(buffer, "%u\n", size);

}



static struct module_attribute modinfo_coresize =

static const struct module_attribute modinfo_coresize =

	__ATTR(coresize, 0444, show_coresize, NULL);



#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC

static ssize_t show_datasize(struct module_attribute *mattr,

static ssize_t show_datasize(const struct module_attribute *mattr,

			     struct module_kobject *mk, char *buffer)

{

	unsigned int size = 0;
@@ -980,11 +980,11 @@ static ssize_t show_datasize(struct module_attribute *mattr, 
	return sprintf(buffer, "%u\n", size);

}



static struct module_attribute modinfo_datasize =

static const struct module_attribute modinfo_datasize =

	__ATTR(datasize, 0444, show_datasize, NULL);

#endif



static ssize_t show_initsize(struct module_attribute *mattr,

static ssize_t show_initsize(const struct module_attribute *mattr,

			     struct module_kobject *mk, char *buffer)

{

	unsigned int size = 0;
@@ -994,10 +994,10 @@ static ssize_t show_initsize(struct module_attribute *mattr, 
	return sprintf(buffer, "%u\n", size);

}



static struct module_attribute modinfo_initsize =

static const struct module_attribute modinfo_initsize =

	__ATTR(initsize, 0444, show_initsize, NULL);



static ssize_t show_taint(struct module_attribute *mattr,

static ssize_t show_taint(const struct module_attribute *mattr,

			  struct module_kobject *mk, char *buffer)

{

	size_t l;
@@ -1007,10 +1007,10 @@ static ssize_t show_taint(struct module_attribute *mattr, 
	return l;

}



static struct module_attribute modinfo_taint =

static const struct module_attribute modinfo_taint =

	__ATTR(taint, 0444, show_taint, NULL);



struct module_attribute *modinfo_attrs[] = {

const struct module_attribute *const modinfo_attrs[] = {

	&module_uevent,

	&modinfo_version,

	&modinfo_srcversion,
@@ -1027,7 +1027,7 @@ struct module_attribute *modinfo_attrs[] = { 
	NULL,

};



size_t modinfo_attrs_count = ARRAY_SIZE(modinfo_attrs);

const size_t modinfo_attrs_count = ARRAY_SIZE(modinfo_attrs);



static const char vermagic[] = VERMAGIC_STRING;
@@ -1681,7 +1681,7 @@ static void module_license_taint_check(struct module *mod, const char *license) 


static void setup_modinfo(struct module *mod, struct load_info *info)

{

	struct module_attribute *attr;

	const struct module_attribute *attr;

	int i;



	for (i = 0; (attr = modinfo_attrs[i]); i++) {
@@ -1692,7 +1692,7 @@ static void setup_modinfo(struct module *mod, struct load_info *info) 


static void free_modinfo(struct module *mod)

{

	struct module_attribute *attr;

	const struct module_attribute *attr;

	int i;



	for (i = 0; (attr = modinfo_attrs[i]); i++) {

kernel/module/sysfs.c

+2 −2
Original line number Diff line number Diff line
@@ -275,7 +275,7 @@ static int add_usage_links(struct module *mod) 


static void module_remove_modinfo_attrs(struct module *mod, int end)

{

	struct module_attribute *attr;

	const struct module_attribute *attr;

	int i;



	for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
@@ -293,7 +293,7 @@ static void module_remove_modinfo_attrs(struct module *mod, int end) 


static int module_add_modinfo_attrs(struct module *mod)

{

	struct module_attribute *attr;

	const struct module_attribute *attr;

	struct module_attribute *temp_attr;

	int error = 0;

	int i;

kernel/params.c

+6 −6
Original line number Diff line number Diff line
@@ -538,7 +538,7 @@ const struct kernel_param_ops param_ops_string = { 
EXPORT_SYMBOL(param_ops_string);



/* sysfs output in /sys/modules/XYZ/parameters/ */

#define to_module_attr(n) container_of(n, struct module_attribute, attr)

#define to_module_attr(n) container_of_const(n, struct module_attribute, attr)

#define to_module_kobject(n) container_of(n, struct module_kobject, kobj)



struct param_attribute
@@ -557,7 +557,7 @@ struct module_param_attrs 
#ifdef CONFIG_SYSFS

#define to_param_attr(n) container_of_const(n, struct param_attribute, mattr)



static ssize_t param_attr_show(struct module_attribute *mattr,

static ssize_t param_attr_show(const struct module_attribute *mattr,

			       struct module_kobject *mk, char *buf)

{

	int count;
@@ -573,7 +573,7 @@ static ssize_t param_attr_show(struct module_attribute *mattr, 
}



/* sysfs always hands a nul-terminated string in buf.  We rely on that. */

static ssize_t param_attr_store(struct module_attribute *mattr,

static ssize_t param_attr_store(const struct module_attribute *mattr,

				struct module_kobject *mk,

				const char *buf, size_t len)

{
@@ -857,7 +857,7 @@ static void __init param_sysfs_builtin(void) 
	}

}



ssize_t __modver_version_show(struct module_attribute *mattr,

ssize_t __modver_version_show(const struct module_attribute *mattr,

			      struct module_kobject *mk, char *buf)

{

	const struct module_version_attribute *vattr =
@@ -892,7 +892,7 @@ static ssize_t module_attr_show(struct kobject *kobj, 
				struct attribute *attr,

				char *buf)

{

	struct module_attribute *attribute;

	const struct module_attribute *attribute;

	struct module_kobject *mk;

	int ret;
@@ -911,7 +911,7 @@ static ssize_t module_attr_store(struct kobject *kobj, 
				struct attribute *attr,

				const char *buf, size_t len)

{

	struct module_attribute *attribute;

	const struct module_attribute *attribute;

	struct module_kobject *mk;

	int ret;