v4.19.13 snapshot.
diff --git a/kernel/params.c b/kernel/params.c
new file mode 100644
index 0000000..ce89f75
--- /dev/null
+++ b/kernel/params.c
@@ -0,0 +1,960 @@
+/* Helpers for initial module or kernel cmdline parsing
+ Copyright (C) 2001 Rusty Russell.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/ctype.h>
+
+#ifdef CONFIG_SYSFS
+/* Protects all built-in parameters, modules use their own param_lock */
+static DEFINE_MUTEX(param_lock);
+
+/* Use the module's mutex, or if built-in use the built-in mutex */
+#ifdef CONFIG_MODULES
+#define KPARAM_MUTEX(mod) ((mod) ? &(mod)->param_lock : ¶m_lock)
+#else
+#define KPARAM_MUTEX(mod) (¶m_lock)
+#endif
+
+static inline void check_kparam_locked(struct module *mod)
+{
+ BUG_ON(!mutex_is_locked(KPARAM_MUTEX(mod)));
+}
+#else
+static inline void check_kparam_locked(struct module *mod)
+{
+}
+#endif /* !CONFIG_SYSFS */
+
+/* This just allows us to keep track of which parameters are kmalloced. */
+struct kmalloced_param {
+ struct list_head list;
+ char val[];
+};
+static LIST_HEAD(kmalloced_params);
+static DEFINE_SPINLOCK(kmalloced_params_lock);
+
+static void *kmalloc_parameter(unsigned int size)
+{
+ struct kmalloced_param *p;
+
+ p = kmalloc(sizeof(*p) + size, GFP_KERNEL);
+ if (!p)
+ return NULL;
+
+ spin_lock(&kmalloced_params_lock);
+ list_add(&p->list, &kmalloced_params);
+ spin_unlock(&kmalloced_params_lock);
+
+ return p->val;
+}
+
+/* Does nothing if parameter wasn't kmalloced above. */
+static void maybe_kfree_parameter(void *param)
+{
+ struct kmalloced_param *p;
+
+ spin_lock(&kmalloced_params_lock);
+ list_for_each_entry(p, &kmalloced_params, list) {
+ if (p->val == param) {
+ list_del(&p->list);
+ kfree(p);
+ break;
+ }
+ }
+ spin_unlock(&kmalloced_params_lock);
+}
+
+static char dash2underscore(char c)
+{
+ if (c == '-')
+ return '_';
+ return c;
+}
+
+bool parameqn(const char *a, const char *b, size_t n)
+{
+ size_t i;
+
+ for (i = 0; i < n; i++) {
+ if (dash2underscore(a[i]) != dash2underscore(b[i]))
+ return false;
+ }
+ return true;
+}
+
+bool parameq(const char *a, const char *b)
+{
+ return parameqn(a, b, strlen(a)+1);
+}
+
+static void param_check_unsafe(const struct kernel_param *kp)
+{
+ if (kp->flags & KERNEL_PARAM_FL_UNSAFE) {
+ pr_notice("Setting dangerous option %s - tainting kernel\n",
+ kp->name);
+ add_taint(TAINT_USER, LOCKDEP_STILL_OK);
+ }
+}
+
+static int parse_one(char *param,
+ char *val,
+ const char *doing,
+ const struct kernel_param *params,
+ unsigned num_params,
+ s16 min_level,
+ s16 max_level,
+ void *arg,
+ int (*handle_unknown)(char *param, char *val,
+ const char *doing, void *arg))
+{
+ unsigned int i;
+ int err;
+
+ /* Find parameter */
+ for (i = 0; i < num_params; i++) {
+ if (parameq(param, params[i].name)) {
+ if (params[i].level < min_level
+ || params[i].level > max_level)
+ return 0;
+ /* No one handled NULL, so do it here. */
+ if (!val &&
+ !(params[i].ops->flags & KERNEL_PARAM_OPS_FL_NOARG))
+ return -EINVAL;
+ pr_debug("handling %s with %p\n", param,
+ params[i].ops->set);
+ kernel_param_lock(params[i].mod);
+ param_check_unsafe(¶ms[i]);
+ err = params[i].ops->set(val, ¶ms[i]);
+ kernel_param_unlock(params[i].mod);
+ return err;
+ }
+ }
+
+ if (handle_unknown) {
+ pr_debug("doing %s: %s='%s'\n", doing, param, val);
+ return handle_unknown(param, val, doing, arg);
+ }
+
+ pr_debug("Unknown argument '%s'\n", param);
+ return -ENOENT;
+}
+
+/* Args looks like "foo=bar,bar2 baz=fuz wiz". */
+char *parse_args(const char *doing,
+ char *args,
+ const struct kernel_param *params,
+ unsigned num,
+ s16 min_level,
+ s16 max_level,
+ void *arg,
+ int (*unknown)(char *param, char *val,
+ const char *doing, void *arg))
+{
+ char *param, *val, *err = NULL;
+
+ /* Chew leading spaces */
+ args = skip_spaces(args);
+
+ if (*args)
+ pr_debug("doing %s, parsing ARGS: '%s'\n", doing, args);
+
+ while (*args) {
+ int ret;
+ int irq_was_disabled;
+
+ args = next_arg(args, ¶m, &val);
+ /* Stop at -- */
+ if (!val && strcmp(param, "--") == 0)
+ return err ?: args;
+ irq_was_disabled = irqs_disabled();
+ ret = parse_one(param, val, doing, params, num,
+ min_level, max_level, arg, unknown);
+ if (irq_was_disabled && !irqs_disabled())
+ pr_warn("%s: option '%s' enabled irq's!\n",
+ doing, param);
+
+ switch (ret) {
+ case 0:
+ continue;
+ case -ENOENT:
+ pr_err("%s: Unknown parameter `%s'\n", doing, param);
+ break;
+ case -ENOSPC:
+ pr_err("%s: `%s' too large for parameter `%s'\n",
+ doing, val ?: "", param);
+ break;
+ default:
+ pr_err("%s: `%s' invalid for parameter `%s'\n",
+ doing, val ?: "", param);
+ break;
+ }
+
+ err = ERR_PTR(ret);
+ }
+
+ return err;
+}
+
+/* Lazy bastard, eh? */
+#define STANDARD_PARAM_DEF(name, type, format, strtolfn) \
+ int param_set_##name(const char *val, const struct kernel_param *kp) \
+ { \
+ return strtolfn(val, 0, (type *)kp->arg); \
+ } \
+ int param_get_##name(char *buffer, const struct kernel_param *kp) \
+ { \
+ return scnprintf(buffer, PAGE_SIZE, format "\n", \
+ *((type *)kp->arg)); \
+ } \
+ const struct kernel_param_ops param_ops_##name = { \
+ .set = param_set_##name, \
+ .get = param_get_##name, \
+ }; \
+ EXPORT_SYMBOL(param_set_##name); \
+ EXPORT_SYMBOL(param_get_##name); \
+ EXPORT_SYMBOL(param_ops_##name)
+
+
+STANDARD_PARAM_DEF(byte, unsigned char, "%hhu", kstrtou8);
+STANDARD_PARAM_DEF(short, short, "%hi", kstrtos16);
+STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", kstrtou16);
+STANDARD_PARAM_DEF(int, int, "%i", kstrtoint);
+STANDARD_PARAM_DEF(uint, unsigned int, "%u", kstrtouint);
+STANDARD_PARAM_DEF(long, long, "%li", kstrtol);
+STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", kstrtoul);
+STANDARD_PARAM_DEF(ullong, unsigned long long, "%llu", kstrtoull);
+
+int param_set_charp(const char *val, const struct kernel_param *kp)
+{
+ if (strlen(val) > 1024) {
+ pr_err("%s: string parameter too long\n", kp->name);
+ return -ENOSPC;
+ }
+
+ maybe_kfree_parameter(*(char **)kp->arg);
+
+ /* This is a hack. We can't kmalloc in early boot, and we
+ * don't need to; this mangled commandline is preserved. */
+ if (slab_is_available()) {
+ *(char **)kp->arg = kmalloc_parameter(strlen(val)+1);
+ if (!*(char **)kp->arg)
+ return -ENOMEM;
+ strcpy(*(char **)kp->arg, val);
+ } else
+ *(const char **)kp->arg = val;
+
+ return 0;
+}
+EXPORT_SYMBOL(param_set_charp);
+
+int param_get_charp(char *buffer, const struct kernel_param *kp)
+{
+ return scnprintf(buffer, PAGE_SIZE, "%s\n", *((char **)kp->arg));
+}
+EXPORT_SYMBOL(param_get_charp);
+
+void param_free_charp(void *arg)
+{
+ maybe_kfree_parameter(*((char **)arg));
+}
+EXPORT_SYMBOL(param_free_charp);
+
+const struct kernel_param_ops param_ops_charp = {
+ .set = param_set_charp,
+ .get = param_get_charp,
+ .free = param_free_charp,
+};
+EXPORT_SYMBOL(param_ops_charp);
+
+/* Actually could be a bool or an int, for historical reasons. */
+int param_set_bool(const char *val, const struct kernel_param *kp)
+{
+ /* No equals means "set"... */
+ if (!val) val = "1";
+
+ /* One of =[yYnN01] */
+ return strtobool(val, kp->arg);
+}
+EXPORT_SYMBOL(param_set_bool);
+
+int param_get_bool(char *buffer, const struct kernel_param *kp)
+{
+ /* Y and N chosen as being relatively non-coder friendly */
+ return sprintf(buffer, "%c\n", *(bool *)kp->arg ? 'Y' : 'N');
+}
+EXPORT_SYMBOL(param_get_bool);
+
+const struct kernel_param_ops param_ops_bool = {
+ .flags = KERNEL_PARAM_OPS_FL_NOARG,
+ .set = param_set_bool,
+ .get = param_get_bool,
+};
+EXPORT_SYMBOL(param_ops_bool);
+
+int param_set_bool_enable_only(const char *val, const struct kernel_param *kp)
+{
+ int err = 0;
+ bool new_value;
+ bool orig_value = *(bool *)kp->arg;
+ struct kernel_param dummy_kp = *kp;
+
+ dummy_kp.arg = &new_value;
+
+ err = param_set_bool(val, &dummy_kp);
+ if (err)
+ return err;
+
+ /* Don't let them unset it once it's set! */
+ if (!new_value && orig_value)
+ return -EROFS;
+
+ if (new_value)
+ err = param_set_bool(val, kp);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(param_set_bool_enable_only);
+
+const struct kernel_param_ops param_ops_bool_enable_only = {
+ .flags = KERNEL_PARAM_OPS_FL_NOARG,
+ .set = param_set_bool_enable_only,
+ .get = param_get_bool,
+};
+EXPORT_SYMBOL_GPL(param_ops_bool_enable_only);
+
+/* This one must be bool. */
+int param_set_invbool(const char *val, const struct kernel_param *kp)
+{
+ int ret;
+ bool boolval;
+ struct kernel_param dummy;
+
+ dummy.arg = &boolval;
+ ret = param_set_bool(val, &dummy);
+ if (ret == 0)
+ *(bool *)kp->arg = !boolval;
+ return ret;
+}
+EXPORT_SYMBOL(param_set_invbool);
+
+int param_get_invbool(char *buffer, const struct kernel_param *kp)
+{
+ return sprintf(buffer, "%c\n", (*(bool *)kp->arg) ? 'N' : 'Y');
+}
+EXPORT_SYMBOL(param_get_invbool);
+
+const struct kernel_param_ops param_ops_invbool = {
+ .set = param_set_invbool,
+ .get = param_get_invbool,
+};
+EXPORT_SYMBOL(param_ops_invbool);
+
+int param_set_bint(const char *val, const struct kernel_param *kp)
+{
+ /* Match bool exactly, by re-using it. */
+ struct kernel_param boolkp = *kp;
+ bool v;
+ int ret;
+
+ boolkp.arg = &v;
+
+ ret = param_set_bool(val, &boolkp);
+ if (ret == 0)
+ *(int *)kp->arg = v;
+ return ret;
+}
+EXPORT_SYMBOL(param_set_bint);
+
+const struct kernel_param_ops param_ops_bint = {
+ .flags = KERNEL_PARAM_OPS_FL_NOARG,
+ .set = param_set_bint,
+ .get = param_get_int,
+};
+EXPORT_SYMBOL(param_ops_bint);
+
+/* We break the rule and mangle the string. */
+static int param_array(struct module *mod,
+ const char *name,
+ const char *val,
+ unsigned int min, unsigned int max,
+ void *elem, int elemsize,
+ int (*set)(const char *, const struct kernel_param *kp),
+ s16 level,
+ unsigned int *num)
+{
+ int ret;
+ struct kernel_param kp;
+ char save;
+
+ /* Get the name right for errors. */
+ kp.name = name;
+ kp.arg = elem;
+ kp.level = level;
+
+ *num = 0;
+ /* We expect a comma-separated list of values. */
+ do {
+ int len;
+
+ if (*num == max) {
+ pr_err("%s: can only take %i arguments\n", name, max);
+ return -EINVAL;
+ }
+ len = strcspn(val, ",");
+
+ /* nul-terminate and parse */
+ save = val[len];
+ ((char *)val)[len] = '\0';
+ check_kparam_locked(mod);
+ ret = set(val, &kp);
+
+ if (ret != 0)
+ return ret;
+ kp.arg += elemsize;
+ val += len+1;
+ (*num)++;
+ } while (save == ',');
+
+ if (*num < min) {
+ pr_err("%s: needs at least %i arguments\n", name, min);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int param_array_set(const char *val, const struct kernel_param *kp)
+{
+ const struct kparam_array *arr = kp->arr;
+ unsigned int temp_num;
+
+ return param_array(kp->mod, kp->name, val, 1, arr->max, arr->elem,
+ arr->elemsize, arr->ops->set, kp->level,
+ arr->num ?: &temp_num);
+}
+
+static int param_array_get(char *buffer, const struct kernel_param *kp)
+{
+ int i, off, ret;
+ const struct kparam_array *arr = kp->arr;
+ struct kernel_param p = *kp;
+
+ for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
+ /* Replace \n with comma */
+ if (i)
+ buffer[off - 1] = ',';
+ p.arg = arr->elem + arr->elemsize * i;
+ check_kparam_locked(p.mod);
+ ret = arr->ops->get(buffer + off, &p);
+ if (ret < 0)
+ return ret;
+ off += ret;
+ }
+ buffer[off] = '\0';
+ return off;
+}
+
+static void param_array_free(void *arg)
+{
+ unsigned int i;
+ const struct kparam_array *arr = arg;
+
+ if (arr->ops->free)
+ for (i = 0; i < (arr->num ? *arr->num : arr->max); i++)
+ arr->ops->free(arr->elem + arr->elemsize * i);
+}
+
+const struct kernel_param_ops param_array_ops = {
+ .set = param_array_set,
+ .get = param_array_get,
+ .free = param_array_free,
+};
+EXPORT_SYMBOL(param_array_ops);
+
+int param_set_copystring(const char *val, const struct kernel_param *kp)
+{
+ const struct kparam_string *kps = kp->str;
+
+ if (strlen(val)+1 > kps->maxlen) {
+ pr_err("%s: string doesn't fit in %u chars.\n",
+ kp->name, kps->maxlen-1);
+ return -ENOSPC;
+ }
+ strcpy(kps->string, val);
+ return 0;
+}
+EXPORT_SYMBOL(param_set_copystring);
+
+int param_get_string(char *buffer, const struct kernel_param *kp)
+{
+ const struct kparam_string *kps = kp->str;
+ return scnprintf(buffer, PAGE_SIZE, "%s\n", kps->string);
+}
+EXPORT_SYMBOL(param_get_string);
+
+const struct kernel_param_ops param_ops_string = {
+ .set = param_set_copystring,
+ .get = param_get_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_kobject(n) container_of(n, struct module_kobject, kobj)
+
+struct param_attribute
+{
+ struct module_attribute mattr;
+ const struct kernel_param *param;
+};
+
+struct module_param_attrs
+{
+ unsigned int num;
+ struct attribute_group grp;
+ struct param_attribute attrs[0];
+};
+
+#ifdef CONFIG_SYSFS
+#define to_param_attr(n) container_of(n, struct param_attribute, mattr)
+
+static ssize_t param_attr_show(struct module_attribute *mattr,
+ struct module_kobject *mk, char *buf)
+{
+ int count;
+ struct param_attribute *attribute = to_param_attr(mattr);
+
+ if (!attribute->param->ops->get)
+ return -EPERM;
+
+ kernel_param_lock(mk->mod);
+ count = attribute->param->ops->get(buf, attribute->param);
+ kernel_param_unlock(mk->mod);
+ return count;
+}
+
+/* sysfs always hands a nul-terminated string in buf. We rely on that. */
+static ssize_t param_attr_store(struct module_attribute *mattr,
+ struct module_kobject *mk,
+ const char *buf, size_t len)
+{
+ int err;
+ struct param_attribute *attribute = to_param_attr(mattr);
+
+ if (!attribute->param->ops->set)
+ return -EPERM;
+
+ kernel_param_lock(mk->mod);
+ param_check_unsafe(attribute->param);
+ err = attribute->param->ops->set(buf, attribute->param);
+ kernel_param_unlock(mk->mod);
+ if (!err)
+ return len;
+ return err;
+}
+#endif
+
+#ifdef CONFIG_MODULES
+#define __modinit
+#else
+#define __modinit __init
+#endif
+
+#ifdef CONFIG_SYSFS
+void kernel_param_lock(struct module *mod)
+{
+ mutex_lock(KPARAM_MUTEX(mod));
+}
+
+void kernel_param_unlock(struct module *mod)
+{
+ mutex_unlock(KPARAM_MUTEX(mod));
+}
+
+EXPORT_SYMBOL(kernel_param_lock);
+EXPORT_SYMBOL(kernel_param_unlock);
+
+/*
+ * add_sysfs_param - add a parameter to sysfs
+ * @mk: struct module_kobject
+ * @kp: the actual parameter definition to add to sysfs
+ * @name: name of parameter
+ *
+ * Create a kobject if for a (per-module) parameter if mp NULL, and
+ * create file in sysfs. Returns an error on out of memory. Always cleans up
+ * if there's an error.
+ */
+static __modinit int add_sysfs_param(struct module_kobject *mk,
+ const struct kernel_param *kp,
+ const char *name)
+{
+ struct module_param_attrs *new_mp;
+ struct attribute **new_attrs;
+ unsigned int i;
+
+ /* We don't bother calling this with invisible parameters. */
+ BUG_ON(!kp->perm);
+
+ if (!mk->mp) {
+ /* First allocation. */
+ mk->mp = kzalloc(sizeof(*mk->mp), GFP_KERNEL);
+ if (!mk->mp)
+ return -ENOMEM;
+ mk->mp->grp.name = "parameters";
+ /* NULL-terminated attribute array. */
+ mk->mp->grp.attrs = kzalloc(sizeof(mk->mp->grp.attrs[0]),
+ GFP_KERNEL);
+ /* Caller will cleanup via free_module_param_attrs */
+ if (!mk->mp->grp.attrs)
+ return -ENOMEM;
+ }
+
+ /* Enlarge allocations. */
+ new_mp = krealloc(mk->mp,
+ sizeof(*mk->mp) +
+ sizeof(mk->mp->attrs[0]) * (mk->mp->num + 1),
+ GFP_KERNEL);
+ if (!new_mp)
+ return -ENOMEM;
+ mk->mp = new_mp;
+
+ /* Extra pointer for NULL terminator */
+ new_attrs = krealloc(mk->mp->grp.attrs,
+ sizeof(mk->mp->grp.attrs[0]) * (mk->mp->num + 2),
+ GFP_KERNEL);
+ if (!new_attrs)
+ return -ENOMEM;
+ mk->mp->grp.attrs = new_attrs;
+
+ /* Tack new one on the end. */
+ memset(&mk->mp->attrs[mk->mp->num], 0, sizeof(mk->mp->attrs[0]));
+ sysfs_attr_init(&mk->mp->attrs[mk->mp->num].mattr.attr);
+ mk->mp->attrs[mk->mp->num].param = kp;
+ mk->mp->attrs[mk->mp->num].mattr.show = param_attr_show;
+ /* Do not allow runtime DAC changes to make param writable. */
+ if ((kp->perm & (S_IWUSR | S_IWGRP | S_IWOTH)) != 0)
+ mk->mp->attrs[mk->mp->num].mattr.store = param_attr_store;
+ else
+ mk->mp->attrs[mk->mp->num].mattr.store = NULL;
+ mk->mp->attrs[mk->mp->num].mattr.attr.name = (char *)name;
+ mk->mp->attrs[mk->mp->num].mattr.attr.mode = kp->perm;
+ mk->mp->num++;
+
+ /* Fix up all the pointers, since krealloc can move us */
+ for (i = 0; i < mk->mp->num; i++)
+ mk->mp->grp.attrs[i] = &mk->mp->attrs[i].mattr.attr;
+ mk->mp->grp.attrs[mk->mp->num] = NULL;
+ return 0;
+}
+
+#ifdef CONFIG_MODULES
+static void free_module_param_attrs(struct module_kobject *mk)
+{
+ if (mk->mp)
+ kfree(mk->mp->grp.attrs);
+ kfree(mk->mp);
+ mk->mp = NULL;
+}
+
+/*
+ * module_param_sysfs_setup - setup sysfs support for one module
+ * @mod: module
+ * @kparam: module parameters (array)
+ * @num_params: number of module parameters
+ *
+ * Adds sysfs entries for module parameters under
+ * /sys/module/[mod->name]/parameters/
+ */
+int module_param_sysfs_setup(struct module *mod,
+ const struct kernel_param *kparam,
+ unsigned int num_params)
+{
+ int i, err;
+ bool params = false;
+
+ for (i = 0; i < num_params; i++) {
+ if (kparam[i].perm == 0)
+ continue;
+ err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
+ if (err) {
+ free_module_param_attrs(&mod->mkobj);
+ return err;
+ }
+ params = true;
+ }
+
+ if (!params)
+ return 0;
+
+ /* Create the param group. */
+ err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
+ if (err)
+ free_module_param_attrs(&mod->mkobj);
+ return err;
+}
+
+/*
+ * module_param_sysfs_remove - remove sysfs support for one module
+ * @mod: module
+ *
+ * Remove sysfs entries for module parameters and the corresponding
+ * kobject.
+ */
+void module_param_sysfs_remove(struct module *mod)
+{
+ if (mod->mkobj.mp) {
+ sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
+ /* We are positive that no one is using any param
+ * attrs at this point. Deallocate immediately. */
+ free_module_param_attrs(&mod->mkobj);
+ }
+}
+#endif
+
+void destroy_params(const struct kernel_param *params, unsigned num)
+{
+ unsigned int i;
+
+ for (i = 0; i < num; i++)
+ if (params[i].ops->free)
+ params[i].ops->free(params[i].arg);
+}
+
+static struct module_kobject * __init locate_module_kobject(const char *name)
+{
+ struct module_kobject *mk;
+ struct kobject *kobj;
+ int err;
+
+ kobj = kset_find_obj(module_kset, name);
+ if (kobj) {
+ mk = to_module_kobject(kobj);
+ } else {
+ mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
+ BUG_ON(!mk);
+
+ mk->mod = THIS_MODULE;
+ mk->kobj.kset = module_kset;
+ err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
+ "%s", name);
+#ifdef CONFIG_MODULES
+ if (!err)
+ err = sysfs_create_file(&mk->kobj, &module_uevent.attr);
+#endif
+ if (err) {
+ kobject_put(&mk->kobj);
+ pr_crit("Adding module '%s' to sysfs failed (%d), the system may be unstable.\n",
+ name, err);
+ return NULL;
+ }
+
+ /* So that we hold reference in both cases. */
+ kobject_get(&mk->kobj);
+ }
+
+ return mk;
+}
+
+static void __init kernel_add_sysfs_param(const char *name,
+ const struct kernel_param *kparam,
+ unsigned int name_skip)
+{
+ struct module_kobject *mk;
+ int err;
+
+ mk = locate_module_kobject(name);
+ if (!mk)
+ return;
+
+ /* We need to remove old parameters before adding more. */
+ if (mk->mp)
+ sysfs_remove_group(&mk->kobj, &mk->mp->grp);
+
+ /* These should not fail at boot. */
+ err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
+ BUG_ON(err);
+ err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
+ BUG_ON(err);
+ kobject_uevent(&mk->kobj, KOBJ_ADD);
+ kobject_put(&mk->kobj);
+}
+
+/*
+ * param_sysfs_builtin - add sysfs parameters for built-in modules
+ *
+ * Add module_parameters to sysfs for "modules" built into the kernel.
+ *
+ * The "module" name (KBUILD_MODNAME) is stored before a dot, the
+ * "parameter" name is stored behind a dot in kernel_param->name. So,
+ * extract the "module" name for all built-in kernel_param-eters,
+ * and for all who have the same, call kernel_add_sysfs_param.
+ */
+static void __init param_sysfs_builtin(void)
+{
+ const struct kernel_param *kp;
+ unsigned int name_len;
+ char modname[MODULE_NAME_LEN];
+
+ for (kp = __start___param; kp < __stop___param; kp++) {
+ char *dot;
+
+ if (kp->perm == 0)
+ continue;
+
+ dot = strchr(kp->name, '.');
+ if (!dot) {
+ /* This happens for core_param() */
+ strcpy(modname, "kernel");
+ name_len = 0;
+ } else {
+ name_len = dot - kp->name + 1;
+ strlcpy(modname, kp->name, name_len);
+ }
+ kernel_add_sysfs_param(modname, kp, name_len);
+ }
+}
+
+ssize_t __modver_version_show(struct module_attribute *mattr,
+ struct module_kobject *mk, char *buf)
+{
+ struct module_version_attribute *vattr =
+ container_of(mattr, struct module_version_attribute, mattr);
+
+ return scnprintf(buf, PAGE_SIZE, "%s\n", vattr->version);
+}
+
+extern const struct module_version_attribute *__start___modver[];
+extern const struct module_version_attribute *__stop___modver[];
+
+static void __init version_sysfs_builtin(void)
+{
+ const struct module_version_attribute **p;
+ struct module_kobject *mk;
+ int err;
+
+ for (p = __start___modver; p < __stop___modver; p++) {
+ const struct module_version_attribute *vattr = *p;
+
+ mk = locate_module_kobject(vattr->module_name);
+ if (mk) {
+ err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr);
+ WARN_ON_ONCE(err);
+ kobject_uevent(&mk->kobj, KOBJ_ADD);
+ kobject_put(&mk->kobj);
+ }
+ }
+}
+
+/* module-related sysfs stuff */
+
+static ssize_t module_attr_show(struct kobject *kobj,
+ struct attribute *attr,
+ char *buf)
+{
+ struct module_attribute *attribute;
+ struct module_kobject *mk;
+ int ret;
+
+ attribute = to_module_attr(attr);
+ mk = to_module_kobject(kobj);
+
+ if (!attribute->show)
+ return -EIO;
+
+ ret = attribute->show(attribute, mk, buf);
+
+ return ret;
+}
+
+static ssize_t module_attr_store(struct kobject *kobj,
+ struct attribute *attr,
+ const char *buf, size_t len)
+{
+ struct module_attribute *attribute;
+ struct module_kobject *mk;
+ int ret;
+
+ attribute = to_module_attr(attr);
+ mk = to_module_kobject(kobj);
+
+ if (!attribute->store)
+ return -EIO;
+
+ ret = attribute->store(attribute, mk, buf, len);
+
+ return ret;
+}
+
+static const struct sysfs_ops module_sysfs_ops = {
+ .show = module_attr_show,
+ .store = module_attr_store,
+};
+
+static int uevent_filter(struct kset *kset, struct kobject *kobj)
+{
+ struct kobj_type *ktype = get_ktype(kobj);
+
+ if (ktype == &module_ktype)
+ return 1;
+ return 0;
+}
+
+static const struct kset_uevent_ops module_uevent_ops = {
+ .filter = uevent_filter,
+};
+
+struct kset *module_kset;
+int module_sysfs_initialized;
+
+static void module_kobj_release(struct kobject *kobj)
+{
+ struct module_kobject *mk = to_module_kobject(kobj);
+ complete(mk->kobj_completion);
+}
+
+struct kobj_type module_ktype = {
+ .release = module_kobj_release,
+ .sysfs_ops = &module_sysfs_ops,
+};
+
+/*
+ * param_sysfs_init - wrapper for built-in params support
+ */
+static int __init param_sysfs_init(void)
+{
+ module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
+ if (!module_kset) {
+ printk(KERN_WARNING "%s (%d): error creating kset\n",
+ __FILE__, __LINE__);
+ return -ENOMEM;
+ }
+ module_sysfs_initialized = 1;
+
+ version_sysfs_builtin();
+ param_sysfs_builtin();
+
+ return 0;
+}
+subsys_initcall(param_sysfs_init);
+
+#endif /* CONFIG_SYSFS */