mirror of
https://github.com/torvalds/linux.git
synced 2024-11-18 01:51:53 +00:00
907b29eb41
There may be cases (most obviously, sysfs-writable charp parameters) where a module needs to prevent sysfs access to parameters. Rather than express this in terms of a big lock, the functions are expressed in terms of what they protect against. This is clearer, esp. if the implementation changes to a module-level or even param-level lock. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Reviewed-by: Takashi Iwai <tiwai@suse.de> Tested-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
885 lines
20 KiB
C
885 lines
20 KiB
C
/* 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/moduleparam.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/string.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/module.h>
|
|
#include <linux/device.h>
|
|
#include <linux/err.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/ctype.h>
|
|
|
|
#if 0
|
|
#define DEBUGP printk
|
|
#else
|
|
#define DEBUGP(fmt, a...)
|
|
#endif
|
|
|
|
/* Protects all parameters, and incidentally kmalloced_param list. */
|
|
static DEFINE_MUTEX(param_lock);
|
|
|
|
/* 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 void *kmalloc_parameter(unsigned int size)
|
|
{
|
|
struct kmalloced_param *p;
|
|
|
|
p = kmalloc(sizeof(*p) + size, GFP_KERNEL);
|
|
if (!p)
|
|
return NULL;
|
|
|
|
list_add(&p->list, &kmalloced_params);
|
|
return p->val;
|
|
}
|
|
|
|
/* Does nothing if parameter wasn't kmalloced above. */
|
|
static void maybe_kfree_parameter(void *param)
|
|
{
|
|
struct kmalloced_param *p;
|
|
|
|
list_for_each_entry(p, &kmalloced_params, list) {
|
|
if (p->val == param) {
|
|
list_del(&p->list);
|
|
kfree(p);
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
static inline char dash2underscore(char c)
|
|
{
|
|
if (c == '-')
|
|
return '_';
|
|
return c;
|
|
}
|
|
|
|
static inline int parameq(const char *input, const char *paramname)
|
|
{
|
|
unsigned int i;
|
|
for (i = 0; dash2underscore(input[i]) == paramname[i]; i++)
|
|
if (input[i] == '\0')
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
static int parse_one(char *param,
|
|
char *val,
|
|
const struct kernel_param *params,
|
|
unsigned num_params,
|
|
int (*handle_unknown)(char *param, char *val))
|
|
{
|
|
unsigned int i;
|
|
int err;
|
|
|
|
/* Find parameter */
|
|
for (i = 0; i < num_params; i++) {
|
|
if (parameq(param, params[i].name)) {
|
|
/* Noone handled NULL, so do it here. */
|
|
if (!val && params[i].ops->set != param_set_bool)
|
|
return -EINVAL;
|
|
DEBUGP("They are equal! Calling %p\n",
|
|
params[i].ops->set);
|
|
mutex_lock(¶m_lock);
|
|
err = params[i].ops->set(val, ¶ms[i]);
|
|
mutex_unlock(¶m_lock);
|
|
return err;
|
|
}
|
|
}
|
|
|
|
if (handle_unknown) {
|
|
DEBUGP("Unknown argument: calling %p\n", handle_unknown);
|
|
return handle_unknown(param, val);
|
|
}
|
|
|
|
DEBUGP("Unknown argument `%s'\n", param);
|
|
return -ENOENT;
|
|
}
|
|
|
|
/* You can use " around spaces, but can't escape ". */
|
|
/* Hyphens and underscores equivalent in parameter names. */
|
|
static char *next_arg(char *args, char **param, char **val)
|
|
{
|
|
unsigned int i, equals = 0;
|
|
int in_quote = 0, quoted = 0;
|
|
char *next;
|
|
|
|
if (*args == '"') {
|
|
args++;
|
|
in_quote = 1;
|
|
quoted = 1;
|
|
}
|
|
|
|
for (i = 0; args[i]; i++) {
|
|
if (isspace(args[i]) && !in_quote)
|
|
break;
|
|
if (equals == 0) {
|
|
if (args[i] == '=')
|
|
equals = i;
|
|
}
|
|
if (args[i] == '"')
|
|
in_quote = !in_quote;
|
|
}
|
|
|
|
*param = args;
|
|
if (!equals)
|
|
*val = NULL;
|
|
else {
|
|
args[equals] = '\0';
|
|
*val = args + equals + 1;
|
|
|
|
/* Don't include quotes in value. */
|
|
if (**val == '"') {
|
|
(*val)++;
|
|
if (args[i-1] == '"')
|
|
args[i-1] = '\0';
|
|
}
|
|
if (quoted && args[i-1] == '"')
|
|
args[i-1] = '\0';
|
|
}
|
|
|
|
if (args[i]) {
|
|
args[i] = '\0';
|
|
next = args + i + 1;
|
|
} else
|
|
next = args + i;
|
|
|
|
/* Chew up trailing spaces. */
|
|
return skip_spaces(next);
|
|
}
|
|
|
|
/* Args looks like "foo=bar,bar2 baz=fuz wiz". */
|
|
int parse_args(const char *name,
|
|
char *args,
|
|
const struct kernel_param *params,
|
|
unsigned num,
|
|
int (*unknown)(char *param, char *val))
|
|
{
|
|
char *param, *val;
|
|
|
|
DEBUGP("Parsing ARGS: %s\n", args);
|
|
|
|
/* Chew leading spaces */
|
|
args = skip_spaces(args);
|
|
|
|
while (*args) {
|
|
int ret;
|
|
int irq_was_disabled;
|
|
|
|
args = next_arg(args, ¶m, &val);
|
|
irq_was_disabled = irqs_disabled();
|
|
ret = parse_one(param, val, params, num, unknown);
|
|
if (irq_was_disabled && !irqs_disabled()) {
|
|
printk(KERN_WARNING "parse_args(): option '%s' enabled "
|
|
"irq's!\n", param);
|
|
}
|
|
switch (ret) {
|
|
case -ENOENT:
|
|
printk(KERN_ERR "%s: Unknown parameter `%s'\n",
|
|
name, param);
|
|
return ret;
|
|
case -ENOSPC:
|
|
printk(KERN_ERR
|
|
"%s: `%s' too large for parameter `%s'\n",
|
|
name, val ?: "", param);
|
|
return ret;
|
|
case 0:
|
|
break;
|
|
default:
|
|
printk(KERN_ERR
|
|
"%s: `%s' invalid for parameter `%s'\n",
|
|
name, val ?: "", param);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
/* All parsed OK. */
|
|
return 0;
|
|
}
|
|
|
|
/* Lazy bastard, eh? */
|
|
#define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
|
|
int param_set_##name(const char *val, const struct kernel_param *kp) \
|
|
{ \
|
|
tmptype l; \
|
|
int ret; \
|
|
\
|
|
ret = strtolfn(val, 0, &l); \
|
|
if (ret == -EINVAL || ((type)l != l)) \
|
|
return -EINVAL; \
|
|
*((type *)kp->arg) = l; \
|
|
return 0; \
|
|
} \
|
|
int param_get_##name(char *buffer, const struct kernel_param *kp) \
|
|
{ \
|
|
return sprintf(buffer, format, *((type *)kp->arg)); \
|
|
} \
|
|
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, "%c", unsigned long, strict_strtoul);
|
|
STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol);
|
|
STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, strict_strtoul);
|
|
STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol);
|
|
STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, strict_strtoul);
|
|
STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol);
|
|
STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, strict_strtoul);
|
|
|
|
int param_set_charp(const char *val, const struct kernel_param *kp)
|
|
{
|
|
if (strlen(val) > 1024) {
|
|
printk(KERN_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 sprintf(buffer, "%s", *((char **)kp->arg));
|
|
}
|
|
EXPORT_SYMBOL(param_get_charp);
|
|
|
|
static void param_free_charp(void *arg)
|
|
{
|
|
maybe_kfree_parameter(*((char **)arg));
|
|
}
|
|
|
|
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)
|
|
{
|
|
bool v;
|
|
|
|
/* No equals means "set"... */
|
|
if (!val) val = "1";
|
|
|
|
/* One of =[yYnN01] */
|
|
switch (val[0]) {
|
|
case 'y': case 'Y': case '1':
|
|
v = true;
|
|
break;
|
|
case 'n': case 'N': case '0':
|
|
v = false;
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (kp->flags & KPARAM_ISBOOL)
|
|
*(bool *)kp->arg = v;
|
|
else
|
|
*(int *)kp->arg = v;
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(param_set_bool);
|
|
|
|
int param_get_bool(char *buffer, const struct kernel_param *kp)
|
|
{
|
|
bool val;
|
|
if (kp->flags & KPARAM_ISBOOL)
|
|
val = *(bool *)kp->arg;
|
|
else
|
|
val = *(int *)kp->arg;
|
|
|
|
/* Y and N chosen as being relatively non-coder friendly */
|
|
return sprintf(buffer, "%c", val ? 'Y' : 'N');
|
|
}
|
|
EXPORT_SYMBOL(param_get_bool);
|
|
|
|
struct kernel_param_ops param_ops_bool = {
|
|
.set = param_set_bool,
|
|
.get = param_get_bool,
|
|
};
|
|
EXPORT_SYMBOL(param_ops_bool);
|
|
|
|
/* 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;
|
|
dummy.flags = KPARAM_ISBOOL;
|
|
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", (*(bool *)kp->arg) ? 'N' : 'Y');
|
|
}
|
|
EXPORT_SYMBOL(param_get_invbool);
|
|
|
|
struct kernel_param_ops param_ops_invbool = {
|
|
.set = param_set_invbool,
|
|
.get = param_get_invbool,
|
|
};
|
|
EXPORT_SYMBOL(param_ops_invbool);
|
|
|
|
/* We break the rule and mangle the string. */
|
|
static int param_array(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),
|
|
u16 flags,
|
|
unsigned int *num)
|
|
{
|
|
int ret;
|
|
struct kernel_param kp;
|
|
char save;
|
|
|
|
/* Get the name right for errors. */
|
|
kp.name = name;
|
|
kp.arg = elem;
|
|
kp.flags = flags;
|
|
|
|
*num = 0;
|
|
/* We expect a comma-separated list of values. */
|
|
do {
|
|
int len;
|
|
|
|
if (*num == max) {
|
|
printk(KERN_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';
|
|
BUG_ON(!mutex_is_locked(¶m_lock));
|
|
ret = set(val, &kp);
|
|
|
|
if (ret != 0)
|
|
return ret;
|
|
kp.arg += elemsize;
|
|
val += len+1;
|
|
(*num)++;
|
|
} while (save == ',');
|
|
|
|
if (*num < min) {
|
|
printk(KERN_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->name, val, 1, arr->max, arr->elem,
|
|
arr->elemsize, arr->ops->set, kp->flags,
|
|
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;
|
|
|
|
p = *kp;
|
|
for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
|
|
if (i)
|
|
buffer[off++] = ',';
|
|
p.arg = arr->elem + arr->elemsize * i;
|
|
BUG_ON(!mutex_is_locked(¶m_lock));
|
|
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);
|
|
}
|
|
|
|
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) {
|
|
printk(KERN_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 strlcpy(buffer, kps->string, kps->maxlen);
|
|
}
|
|
EXPORT_SYMBOL(param_get_string);
|
|
|
|
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)
|
|
|
|
extern struct kernel_param __start___param[], __stop___param[];
|
|
|
|
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 *mod, char *buf)
|
|
{
|
|
int count;
|
|
struct param_attribute *attribute = to_param_attr(mattr);
|
|
|
|
if (!attribute->param->ops->get)
|
|
return -EPERM;
|
|
|
|
mutex_lock(¶m_lock);
|
|
count = attribute->param->ops->get(buf, attribute->param);
|
|
mutex_unlock(¶m_lock);
|
|
if (count > 0) {
|
|
strcat(buf, "\n");
|
|
++count;
|
|
}
|
|
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 *owner,
|
|
const char *buf, size_t len)
|
|
{
|
|
int err;
|
|
struct param_attribute *attribute = to_param_attr(mattr);
|
|
|
|
if (!attribute->param->ops->set)
|
|
return -EPERM;
|
|
|
|
mutex_lock(¶m_lock);
|
|
err = attribute->param->ops->set(buf, attribute->param);
|
|
mutex_unlock(¶m_lock);
|
|
if (!err)
|
|
return len;
|
|
return err;
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_MODULES
|
|
#define __modinit
|
|
#else
|
|
#define __modinit __init
|
|
#endif
|
|
|
|
#ifdef CONFIG_SYSFS
|
|
void __kernel_param_lock(void)
|
|
{
|
|
mutex_lock(¶m_lock);
|
|
}
|
|
EXPORT_SYMBOL(__kernel_param_lock);
|
|
|
|
void __kernel_param_unlock(void)
|
|
{
|
|
mutex_unlock(¶m_lock);
|
|
}
|
|
EXPORT_SYMBOL(__kernel_param_unlock);
|
|
|
|
/*
|
|
* add_sysfs_param - add a parameter to sysfs
|
|
* @mk: struct module_kobject
|
|
* @kparam: 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;
|
|
struct attribute **attrs;
|
|
int err, num;
|
|
|
|
/* We don't bother calling this with invisible parameters. */
|
|
BUG_ON(!kp->perm);
|
|
|
|
if (!mk->mp) {
|
|
num = 0;
|
|
attrs = NULL;
|
|
} else {
|
|
num = mk->mp->num;
|
|
attrs = mk->mp->grp.attrs;
|
|
}
|
|
|
|
/* Enlarge. */
|
|
new = krealloc(mk->mp,
|
|
sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1),
|
|
GFP_KERNEL);
|
|
if (!new) {
|
|
kfree(mk->mp);
|
|
err = -ENOMEM;
|
|
goto fail;
|
|
}
|
|
attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL);
|
|
if (!attrs) {
|
|
err = -ENOMEM;
|
|
goto fail_free_new;
|
|
}
|
|
|
|
/* Sysfs wants everything zeroed. */
|
|
memset(new, 0, sizeof(*new));
|
|
memset(&new->attrs[num], 0, sizeof(new->attrs[num]));
|
|
memset(&attrs[num], 0, sizeof(attrs[num]));
|
|
new->grp.name = "parameters";
|
|
new->grp.attrs = attrs;
|
|
|
|
/* Tack new one on the end. */
|
|
sysfs_attr_init(&new->attrs[num].mattr.attr);
|
|
new->attrs[num].param = kp;
|
|
new->attrs[num].mattr.show = param_attr_show;
|
|
new->attrs[num].mattr.store = param_attr_store;
|
|
new->attrs[num].mattr.attr.name = (char *)name;
|
|
new->attrs[num].mattr.attr.mode = kp->perm;
|
|
new->num = num+1;
|
|
|
|
/* Fix up all the pointers, since krealloc can move us */
|
|
for (num = 0; num < new->num; num++)
|
|
new->grp.attrs[num] = &new->attrs[num].mattr.attr;
|
|
new->grp.attrs[num] = NULL;
|
|
|
|
mk->mp = new;
|
|
return 0;
|
|
|
|
fail_free_new:
|
|
kfree(new);
|
|
fail:
|
|
mk->mp = NULL;
|
|
return err;
|
|
}
|
|
|
|
#ifdef CONFIG_MODULES
|
|
static void free_module_param_attrs(struct module_kobject *mk)
|
|
{
|
|
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)
|
|
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 void __init kernel_add_sysfs_param(const char *name,
|
|
struct kernel_param *kparam,
|
|
unsigned int name_skip)
|
|
{
|
|
struct module_kobject *mk;
|
|
struct kobject *kobj;
|
|
int err;
|
|
|
|
kobj = kset_find_obj(module_kset, name);
|
|
if (kobj) {
|
|
/* We already have one. Remove params so we can add more. */
|
|
mk = to_module_kobject(kobj);
|
|
/* We need to remove it before adding parameters. */
|
|
sysfs_remove_group(&mk->kobj, &mk->mp->grp);
|
|
} 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);
|
|
if (err) {
|
|
kobject_put(&mk->kobj);
|
|
printk(KERN_ERR "Module '%s' failed add to sysfs, "
|
|
"error number %d\n", name, err);
|
|
printk(KERN_ERR "The system will be unstable now.\n");
|
|
return;
|
|
}
|
|
/* So that exit path is even. */
|
|
kobject_get(&mk->kobj);
|
|
}
|
|
|
|
/* 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 contents in /sys/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)
|
|
{
|
|
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);
|
|
}
|
|
}
|
|
|
|
|
|
/* 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->mod, 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->mod, 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;
|
|
|
|
struct kobj_type module_ktype = {
|
|
.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;
|
|
|
|
param_sysfs_builtin();
|
|
|
|
return 0;
|
|
}
|
|
subsys_initcall(param_sysfs_init);
|
|
|
|
#endif /* CONFIG_SYSFS */
|