kernel/module/sysfs.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Module sysfs support
  *
  * Copyright (C) 2008 Rusty Russell
  */

 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/fs.h>
 #include <linux/sysfs.h>
 #include <linux/slab.h>
 #include <linux/kallsyms.h>
 #include <linux/mutex.h>
 #include "internal.h"

 /*
  * /sys/module/foo/sections stuff
  * J. Corbet <corbet@lwn.net>
  */
 #ifdef CONFIG_KALLSYMS
 struct module_sect_attr {
 	struct bin_attribute battr;
 	unsigned long address;
 };

 struct module_sect_attrs {
 	struct attribute_group grp;
 	unsigned int nsections;
 	struct module_sect_attr attrs[];
 };

 #define MODULE_SECT_READ_SIZE (3 /* "0x", "\n" */ + (BITS_PER_LONG / 4))
 static ssize_t module_sect_read(struct file *file, struct kobject *kobj,
 				struct bin_attribute *battr,
 				char *buf, loff_t pos, size_t count)
 {
 	struct module_sect_attr *sattr =
 		container_of(battr, struct module_sect_attr, battr);
 	char bounce[MODULE_SECT_READ_SIZE + 1];
 	size_t wrote;

 	if (pos != 0)
 		return -EINVAL;

 	/*
 	 * Since we're a binary read handler, we must account for the
 	 * trailing NUL byte that sprintf will write: if "buf" is
 	 * too small to hold the NUL, or the NUL is exactly the last
 	 * byte, the read will look like it got truncated by one byte.
 	 * Since there is no way to ask sprintf nicely to not write
 	 * the NUL, we have to use a bounce buffer.
 	 */
 	wrote = scnprintf(bounce, sizeof(bounce), "0x%px\n",
 			  kallsyms_show_value(file->f_cred)
 				? (void *)sattr->address : NULL);
 	count = min(count, wrote);
 	memcpy(buf, bounce, count);

 	return count;
 }

 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
 {
 	unsigned int section;

 	for (section = 0; section < sect_attrs->nsections; section++)
 		kfree(sect_attrs->attrs[section].battr.attr.name);
 	kfree(sect_attrs);
 }

 static void add_sect_attrs(struct module *mod, const struct load_info *info)
 {
 	unsigned int nloaded = 0, i, size[2];
 	struct module_sect_attrs *sect_attrs;
 	struct module_sect_attr *sattr;
 	struct bin_attribute **gattr;

 	/* Count loaded sections and allocate structures */
 	for (i = 0; i < info->hdr->e_shnum; i++)
 		if (!sect_empty(&info->sechdrs[i]))
 			nloaded++;
 	size[0] = ALIGN(struct_size(sect_attrs, attrs, nloaded),
 			sizeof(sect_attrs->grp.bin_attrs[0]));
 	size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.bin_attrs[0]);
 	sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
 	if (!sect_attrs)
 		return;

 	/* Setup section attributes. */
 	sect_attrs->grp.name = "sections";
 	sect_attrs->grp.bin_attrs = (void *)sect_attrs + size[0];

 	sect_attrs->nsections = 0;
 	sattr = &sect_attrs->attrs[0];
 	gattr = &sect_attrs->grp.bin_attrs[0];
 	for (i = 0; i < info->hdr->e_shnum; i++) {
 		Elf_Shdr *sec = &info->sechdrs[i];

 		if (sect_empty(sec))
 			continue;
 		sysfs_bin_attr_init(&sattr->battr);
 		sattr->address = sec->sh_addr;
 		sattr->battr.attr.name =
 			kstrdup(info->secstrings + sec->sh_name, GFP_KERNEL);
 		if (!sattr->battr.attr.name)
 			goto out;
 		sect_attrs->nsections++;
 		sattr->battr.read = module_sect_read;
 		sattr->battr.size = MODULE_SECT_READ_SIZE;
 		sattr->battr.attr.mode = 0400;
 		*(gattr++) = &(sattr++)->battr;
 	}
 	*gattr = NULL;

 	if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
 		goto out;

 	mod->sect_attrs = sect_attrs;
 	return;
 out:
 	free_sect_attrs(sect_attrs);
 }

 static void remove_sect_attrs(struct module *mod)
 {
 	if (mod->sect_attrs) {
 		sysfs_remove_group(&mod->mkobj.kobj,
 				   &mod->sect_attrs->grp);
 		/*
 		 * We are positive that no one is using any sect attrs
 		 * at this point.  Deallocate immediately.
 		 */
 		free_sect_attrs(mod->sect_attrs);
 		mod->sect_attrs = NULL;
 	}
 }

 /*
  * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
  */

 struct module_notes_attrs {
 	struct kobject *dir;
 	unsigned int notes;
 	struct bin_attribute attrs[] __counted_by(notes);
 };

 static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
 				 struct bin_attribute *bin_attr,
 				 char *buf, loff_t pos, size_t count)
 {
 	/*
 	 * The caller checked the pos and count against our size.
 	 */
 	memcpy(buf, bin_attr->private + pos, count);
 	return count;
 }

 static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
 			     unsigned int i)
 {
 	if (notes_attrs->dir) {
 		while (i-- > 0)
 			sysfs_remove_bin_file(notes_attrs->dir,
 					      &notes_attrs->attrs[i]);
 		kobject_put(notes_attrs->dir);
 	}
 	kfree(notes_attrs);
 }

 static void add_notes_attrs(struct module *mod, const struct load_info *info)
 {
 	unsigned int notes, loaded, i;
 	struct module_notes_attrs *notes_attrs;
 	struct bin_attribute *nattr;

 	/* failed to create section attributes, so can't create notes */
 	if (!mod->sect_attrs)
 		return;

 	/* Count notes sections and allocate structures.  */
 	notes = 0;
 	for (i = 0; i < info->hdr->e_shnum; i++)
 		if (!sect_empty(&info->sechdrs[i]) &&
 		    info->sechdrs[i].sh_type == SHT_NOTE)
 			++notes;

 	if (notes == 0)
 		return;

 	notes_attrs = kzalloc(struct_size(notes_attrs, attrs, notes),
 			      GFP_KERNEL);
 	if (!notes_attrs)
 		return;

 	notes_attrs->notes = notes;
 	nattr = &notes_attrs->attrs[0];
 	for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
 		if (sect_empty(&info->sechdrs[i]))
 			continue;
 		if (info->sechdrs[i].sh_type == SHT_NOTE) {
 			sysfs_bin_attr_init(nattr);
 			nattr->attr.name = mod->sect_attrs->attrs[loaded].battr.attr.name;
 			nattr->attr.mode = 0444;
 			nattr->size = info->sechdrs[i].sh_size;
 			nattr->private = (void *)info->sechdrs[i].sh_addr;
 			nattr->read = module_notes_read;
 			++nattr;
 		}
 		++loaded;
 	}

 	notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
 	if (!notes_attrs->dir)
 		goto out;

 	for (i = 0; i < notes; ++i)
 		if (sysfs_create_bin_file(notes_attrs->dir,
 					  &notes_attrs->attrs[i]))
 			goto out;

 	mod->notes_attrs = notes_attrs;
 	return;

 out:
 	free_notes_attrs(notes_attrs, i);
 }

 static void remove_notes_attrs(struct module *mod)
 {
 	if (mod->notes_attrs)
 		free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
 }

 #else /* !CONFIG_KALLSYMS */
 static inline void add_sect_attrs(struct module *mod, const struct load_info *info) { }
 static inline void remove_sect_attrs(struct module *mod) { }
 static inline void add_notes_attrs(struct module *mod, const struct load_info *info) { }
 static inline void remove_notes_attrs(struct module *mod) { }
 #endif /* CONFIG_KALLSYMS */

 static void del_usage_links(struct module *mod)
 {
 #ifdef CONFIG_MODULE_UNLOAD
 	struct module_use *use;

 	mutex_lock(&module_mutex);
 	list_for_each_entry(use, &mod->target_list, target_list)
 		sysfs_remove_link(use->target->holders_dir, mod->name);
 	mutex_unlock(&module_mutex);
 #endif
 }

 static int add_usage_links(struct module *mod)
 {
 	int ret = 0;
 #ifdef CONFIG_MODULE_UNLOAD
 	struct module_use *use;

 	mutex_lock(&module_mutex);
 	list_for_each_entry(use, &mod->target_list, target_list) {
 		ret = sysfs_create_link(use->target->holders_dir,
 					&mod->mkobj.kobj, mod->name);
 		if (ret)
 			break;
 	}
 	mutex_unlock(&module_mutex);
 	if (ret)
 		del_usage_links(mod);
 #endif
 	return ret;
 }

 static void module_remove_modinfo_attrs(struct module *mod, int end)
 {
 	struct module_attribute *attr;
 	int i;

 	for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
 		if (end >= 0 && i > end)
 			break;
 		/* pick a field to test for end of list */
 		if (!attr->attr.name)
 			break;
 		sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
 		if (attr->free)
 			attr->free(mod);
 	}
 	kfree(mod->modinfo_attrs);
 }

 static int module_add_modinfo_attrs(struct module *mod)
 {
 	struct module_attribute *attr;
 	struct module_attribute *temp_attr;
 	int error = 0;
 	int i;

 	mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
 					(modinfo_attrs_count + 1)),
 					GFP_KERNEL);
 	if (!mod->modinfo_attrs)
 		return -ENOMEM;

 	temp_attr = mod->modinfo_attrs;
 	for (i = 0; (attr = modinfo_attrs[i]); i++) {
 		if (!attr->test || attr->test(mod)) {
 			memcpy(temp_attr, attr, sizeof(*temp_attr));
 			sysfs_attr_init(&temp_attr->attr);
 			error = sysfs_create_file(&mod->mkobj.kobj,
 						  &temp_attr->attr);
 			if (error)
 				goto error_out;
 			++temp_attr;
 		}
 	}

 	return 0;

 error_out:
 	if (i > 0)
 		module_remove_modinfo_attrs(mod, --i);
 	else
 		kfree(mod->modinfo_attrs);
 	return error;
 }

 static void mod_kobject_put(struct module *mod)
 {
 	DECLARE_COMPLETION_ONSTACK(c);

 	mod->mkobj.kobj_completion = &c;
 	kobject_put(&mod->mkobj.kobj);
 	wait_for_completion(&c);
 }

 static int mod_sysfs_init(struct module *mod)
 {
 	int err;
 	struct kobject *kobj;

 	if (!module_kset) {
 		pr_err("%s: module sysfs not initialized\n", mod->name);
 		err = -EINVAL;
 		goto out;
 	}

 	kobj = kset_find_obj(module_kset, mod->name);
 	if (kobj) {
 		pr_err("%s: module is already loaded\n", mod->name);
 		kobject_put(kobj);
 		err = -EINVAL;
 		goto out;
 	}

 	mod->mkobj.mod = mod;

 	memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
 	mod->mkobj.kobj.kset = module_kset;
 	err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
 				   "%s", mod->name);
 	if (err)
 		mod_kobject_put(mod);

 out:
 	return err;
 }

 int mod_sysfs_setup(struct module *mod,
 		    const struct load_info *info,
 			   struct kernel_param *kparam,
 			   unsigned int num_params)
 {
 	int err;

 	err = mod_sysfs_init(mod);
 	if (err)
 		goto out;

 	mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
 	if (!mod->holders_dir) {
 		err = -ENOMEM;
 		goto out_unreg;
 	}

 	err = module_param_sysfs_setup(mod, kparam, num_params);
 	if (err)
 		goto out_unreg_holders;

 	err = module_add_modinfo_attrs(mod);
 	if (err)
 		goto out_unreg_param;

 	err = add_usage_links(mod);
 	if (err)
 		goto out_unreg_modinfo_attrs;

 	add_sect_attrs(mod, info);
 	add_notes_attrs(mod, info);

 	return 0;

 out_unreg_modinfo_attrs:
 	module_remove_modinfo_attrs(mod, -1);
 out_unreg_param:
 	module_param_sysfs_remove(mod);
 out_unreg_holders:
 	kobject_put(mod->holders_dir);
 out_unreg:
 	mod_kobject_put(mod);
 out:
 	return err;
 }

 static void mod_sysfs_fini(struct module *mod)
 {
 	remove_notes_attrs(mod);
 	remove_sect_attrs(mod);
 	mod_kobject_put(mod);
 }

 void mod_sysfs_teardown(struct module *mod)
 {
 	del_usage_links(mod);
 	module_remove_modinfo_attrs(mod, -1);
 	module_param_sysfs_remove(mod);
 	kobject_put(mod->mkobj.drivers_dir);
 	kobject_put(mod->holders_dir);
 	mod_sysfs_fini(mod);
 }

 void init_param_lock(struct module *mod)
 {
 	mutex_init(&mod->param_lock);
 }
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* Module sysfs support
	*
	* Copyright (C) 2008 Rusty Russell
	*/

	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/fs.h>
	#include <linux/sysfs.h>
	#include <linux/slab.h>
	#include <linux/kallsyms.h>
	#include <linux/mutex.h>
	#include "internal.h"

	/*
	* /sys/module/foo/sections stuff
	* J. Corbet <corbet@lwn.net>
	*/
	#ifdef CONFIG_KALLSYMS
	struct module_sect_attr {
	struct bin_attribute battr;
	unsigned long address;
	};

	struct module_sect_attrs {
	struct attribute_group grp;
	unsigned int nsections;
	struct module_sect_attr attrs[];
	};

	#define MODULE_SECT_READ_SIZE (3 /* "0x", "\n" */ + (BITS_PER_LONG / 4))
	static ssize_t module_sect_read(struct file file, struct kobject kobj,
	struct bin_attribute *battr,
	char *buf, loff_t pos, size_t count)
	{
	struct module_sect_attr *sattr =
	container_of(battr, struct module_sect_attr, battr);
	char bounce[MODULE_SECT_READ_SIZE + 1];
	size_t wrote;

	if (pos != 0)
	return -EINVAL;

	/*
	* Since we're a binary read handler, we must account for the
	* trailing NUL byte that sprintf will write: if "buf" is
	* too small to hold the NUL, or the NUL is exactly the last
	* byte, the read will look like it got truncated by one byte.
	* Since there is no way to ask sprintf nicely to not write
	* the NUL, we have to use a bounce buffer.
	*/
	wrote = scnprintf(bounce, sizeof(bounce), "0x%px\n",
	kallsyms_show_value(file->f_cred)
	? (void *)sattr->address : NULL);
	count = min(count, wrote);
	memcpy(buf, bounce, count);

	return count;
	}

	static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
	{
	unsigned int section;

	for (section = 0; section < sect_attrs->nsections; section++)
	kfree(sect_attrs->attrs[section].battr.attr.name);
	kfree(sect_attrs);
	}

	static void add_sect_attrs(struct module mod, const struct load_info info)
	{
	unsigned int nloaded = 0, i, size[2];
	struct module_sect_attrs *sect_attrs;
	struct module_sect_attr *sattr;
	struct bin_attribute **gattr;

	/* Count loaded sections and allocate structures */
	for (i = 0; i < info->hdr->e_shnum; i++)
	if (!sect_empty(&info->sechdrs[i]))
	nloaded++;
	size[0] = ALIGN(struct_size(sect_attrs, attrs, nloaded),
	sizeof(sect_attrs->grp.bin_attrs[0]));
	size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.bin_attrs[0]);
	sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
	if (!sect_attrs)
	return;

	/* Setup section attributes. */
	sect_attrs->grp.name = "sections";
	sect_attrs->grp.bin_attrs = (void *)sect_attrs + size[0];

	sect_attrs->nsections = 0;
	sattr = &sect_attrs->attrs[0];
	gattr = &sect_attrs->grp.bin_attrs[0];
	for (i = 0; i < info->hdr->e_shnum; i++) {
	Elf_Shdr *sec = &info->sechdrs[i];

	if (sect_empty(sec))
	continue;
	sysfs_bin_attr_init(&sattr->battr);
	sattr->address = sec->sh_addr;
	sattr->battr.attr.name =
	kstrdup(info->secstrings + sec->sh_name, GFP_KERNEL);
	if (!sattr->battr.attr.name)
	goto out;
	sect_attrs->nsections++;
	sattr->battr.read = module_sect_read;
	sattr->battr.size = MODULE_SECT_READ_SIZE;
	sattr->battr.attr.mode = 0400;
	*(gattr++) = &(sattr++)->battr;
	}
	*gattr = NULL;

	if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
	goto out;

	mod->sect_attrs = sect_attrs;
	return;
	out:
	free_sect_attrs(sect_attrs);
	}

	static void remove_sect_attrs(struct module *mod)
	{
	if (mod->sect_attrs) {
	sysfs_remove_group(&mod->mkobj.kobj,
	&mod->sect_attrs->grp);
	/*
	* We are positive that no one is using any sect attrs
	* at this point. Deallocate immediately.
	*/
	free_sect_attrs(mod->sect_attrs);
	mod->sect_attrs = NULL;
	}
	}

	/*
	* /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
	*/

	struct module_notes_attrs {
	struct kobject *dir;
	unsigned int notes;
	struct bin_attribute attrs[] __counted_by(notes);
	};

	static ssize_t module_notes_read(struct file filp, struct kobject kobj,
	struct bin_attribute *bin_attr,
	char *buf, loff_t pos, size_t count)
	{
	/*
	* The caller checked the pos and count against our size.
	*/
	memcpy(buf, bin_attr->private + pos, count);
	return count;
	}

	static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
	unsigned int i)
	{
	if (notes_attrs->dir) {
	while (i-- > 0)
	sysfs_remove_bin_file(notes_attrs->dir,
	&notes_attrs->attrs[i]);
	kobject_put(notes_attrs->dir);
	}
	kfree(notes_attrs);
	}

	static void add_notes_attrs(struct module mod, const struct load_info info)
	{
	unsigned int notes, loaded, i;
	struct module_notes_attrs *notes_attrs;
	struct bin_attribute *nattr;

	/* failed to create section attributes, so can't create notes */
	if (!mod->sect_attrs)
	return;

	/* Count notes sections and allocate structures. */
	notes = 0;
	for (i = 0; i < info->hdr->e_shnum; i++)
	if (!sect_empty(&info->sechdrs[i]) &&
	info->sechdrs[i].sh_type == SHT_NOTE)
	++notes;

	if (notes == 0)
	return;

	notes_attrs = kzalloc(struct_size(notes_attrs, attrs, notes),
	GFP_KERNEL);
	if (!notes_attrs)
	return;

	notes_attrs->notes = notes;
	nattr = &notes_attrs->attrs[0];
	for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
	if (sect_empty(&info->sechdrs[i]))
	continue;
	if (info->sechdrs[i].sh_type == SHT_NOTE) {
	sysfs_bin_attr_init(nattr);
	nattr->attr.name = mod->sect_attrs->attrs[loaded].battr.attr.name;
	nattr->attr.mode = 0444;
	nattr->size = info->sechdrs[i].sh_size;
	nattr->private = (void *)info->sechdrs[i].sh_addr;
	nattr->read = module_notes_read;
	++nattr;
	}
	++loaded;
	}

	notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
	if (!notes_attrs->dir)
	goto out;

	for (i = 0; i < notes; ++i)
	if (sysfs_create_bin_file(notes_attrs->dir,
	&notes_attrs->attrs[i]))
	goto out;

	mod->notes_attrs = notes_attrs;
	return;

	out:
	free_notes_attrs(notes_attrs, i);
	}

	static void remove_notes_attrs(struct module *mod)
	{
	if (mod->notes_attrs)
	free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
	}

	#else /* !CONFIG_KALLSYMS */
	static inline void add_sect_attrs(struct module mod, const struct load_info info) { }
	static inline void remove_sect_attrs(struct module *mod) { }
	static inline void add_notes_attrs(struct module mod, const struct load_info info) { }
	static inline void remove_notes_attrs(struct module *mod) { }
	#endif /* CONFIG_KALLSYMS */

	static void del_usage_links(struct module *mod)
	{
	#ifdef CONFIG_MODULE_UNLOAD
	struct module_use *use;

	mutex_lock(&module_mutex);
	list_for_each_entry(use, &mod->target_list, target_list)
	sysfs_remove_link(use->target->holders_dir, mod->name);
	mutex_unlock(&module_mutex);
	#endif
	}

	static int add_usage_links(struct module *mod)
	{
	int ret = 0;
	#ifdef CONFIG_MODULE_UNLOAD
	struct module_use *use;

	mutex_lock(&module_mutex);
	list_for_each_entry(use, &mod->target_list, target_list) {
	ret = sysfs_create_link(use->target->holders_dir,
	&mod->mkobj.kobj, mod->name);
	if (ret)
	break;
	}
	mutex_unlock(&module_mutex);
	if (ret)
	del_usage_links(mod);
	#endif
	return ret;
	}

	static void module_remove_modinfo_attrs(struct module *mod, int end)
	{
	struct module_attribute *attr;
	int i;

	for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
	if (end >= 0 && i > end)
	break;
	/* pick a field to test for end of list */
	if (!attr->attr.name)
	break;
	sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
	if (attr->free)
	attr->free(mod);
	}
	kfree(mod->modinfo_attrs);
	}

	static int module_add_modinfo_attrs(struct module *mod)
	{
	struct module_attribute *attr;
	struct module_attribute *temp_attr;
	int error = 0;
	int i;

	mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
	(modinfo_attrs_count + 1)),
	GFP_KERNEL);
	if (!mod->modinfo_attrs)
	return -ENOMEM;

	temp_attr = mod->modinfo_attrs;
	for (i = 0; (attr = modinfo_attrs[i]); i++) {
	if (!attr->test \|\| attr->test(mod)) {
	memcpy(temp_attr, attr, sizeof(*temp_attr));
	sysfs_attr_init(&temp_attr->attr);
	error = sysfs_create_file(&mod->mkobj.kobj,
	&temp_attr->attr);
	if (error)
	goto error_out;
	++temp_attr;
	}
	}

	return 0;

	error_out:
	if (i > 0)
	module_remove_modinfo_attrs(mod, --i);
	else
	kfree(mod->modinfo_attrs);
	return error;
	}

	static void mod_kobject_put(struct module *mod)
	{
	DECLARE_COMPLETION_ONSTACK(c);

	mod->mkobj.kobj_completion = &c;
	kobject_put(&mod->mkobj.kobj);
	wait_for_completion(&c);
	}

	static int mod_sysfs_init(struct module *mod)
	{
	int err;
	struct kobject *kobj;

	if (!module_kset) {
	pr_err("%s: module sysfs not initialized\n", mod->name);
	err = -EINVAL;
	goto out;
	}

	kobj = kset_find_obj(module_kset, mod->name);
	if (kobj) {
	pr_err("%s: module is already loaded\n", mod->name);
	kobject_put(kobj);
	err = -EINVAL;
	goto out;
	}

	mod->mkobj.mod = mod;

	memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
	mod->mkobj.kobj.kset = module_kset;
	err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
	"%s", mod->name);
	if (err)
	mod_kobject_put(mod);

	out:
	return err;
	}

	int mod_sysfs_setup(struct module *mod,
	const struct load_info *info,
	struct kernel_param *kparam,
	unsigned int num_params)
	{
	int err;

	err = mod_sysfs_init(mod);
	if (err)
	goto out;

	mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
	if (!mod->holders_dir) {
	err = -ENOMEM;
	goto out_unreg;
	}

	err = module_param_sysfs_setup(mod, kparam, num_params);
	if (err)
	goto out_unreg_holders;

	err = module_add_modinfo_attrs(mod);
	if (err)
	goto out_unreg_param;

	err = add_usage_links(mod);
	if (err)
	goto out_unreg_modinfo_attrs;

	add_sect_attrs(mod, info);
	add_notes_attrs(mod, info);

	return 0;

	out_unreg_modinfo_attrs:
	module_remove_modinfo_attrs(mod, -1);
	out_unreg_param:
	module_param_sysfs_remove(mod);
	out_unreg_holders:
	kobject_put(mod->holders_dir);
	out_unreg:
	mod_kobject_put(mod);
	out:
	return err;
	}

	static void mod_sysfs_fini(struct module *mod)
	{
	remove_notes_attrs(mod);
	remove_sect_attrs(mod);
	mod_kobject_put(mod);
	}

	void mod_sysfs_teardown(struct module *mod)
	{
	del_usage_links(mod);
	module_remove_modinfo_attrs(mod, -1);
	module_param_sysfs_remove(mod);
	kobject_put(mod->mkobj.drivers_dir);
	kobject_put(mod->holders_dir);
	mod_sysfs_fini(mod);
	}

	void init_param_lock(struct module *mod)
	{
	mutex_init(&mod->param_lock);
	}