diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 22:20:36 (GMT) |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 22:20:36 (GMT) |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /kernel/params.c | |
download | linux-fsl-qoriq-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'kernel/params.c')
-rw-r--r-- | kernel/params.c | 721 |
1 files changed, 721 insertions, 0 deletions
diff --git a/kernel/params.c b/kernel/params.c new file mode 100644 index 0000000..5538608 --- /dev/null +++ b/kernel/params.c @@ -0,0 +1,721 @@ +/* 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/config.h> +#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> + +#if 0 +#define DEBUGP printk +#else +#define DEBUGP(fmt, a...) +#endif + +static inline int 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, + struct kernel_param *params, + unsigned num_params, + int (*handle_unknown)(char *param, char *val)) +{ + unsigned int i; + + /* Find parameter */ + for (i = 0; i < num_params; i++) { + if (parameq(param, params[i].name)) { + DEBUGP("They are equal! Calling %p\n", + params[i].set); + return params[i].set(val, ¶ms[i]); + } + } + + 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; + + /* Chew any extra spaces */ + while (*args == ' ') args++; + if (*args == '"') { + args++; + in_quote = 1; + quoted = 1; + } + + for (i = 0; args[i]; i++) { + if (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; + return next; +} + +/* Args looks like "foo=bar,bar2 baz=fuz wiz". */ +int parse_args(const char *name, + char *args, + struct kernel_param *params, + unsigned num, + int (*unknown)(char *param, char *val)) +{ + char *param, *val; + + DEBUGP("Parsing ARGS: %s\n", args); + + while (*args) { + int ret; + + args = next_arg(args, ¶m, &val); + ret = parse_one(param, val, params, num, unknown); + 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, struct kernel_param *kp) \ + { \ + char *endp; \ + tmptype l; \ + \ + if (!val) return -EINVAL; \ + l = strtolfn(val, &endp, 0); \ + if (endp == val || ((type)l != l)) \ + return -EINVAL; \ + *((type *)kp->arg) = l; \ + return 0; \ + } \ + int param_get_##name(char *buffer, struct kernel_param *kp) \ + { \ + return sprintf(buffer, format, *((type *)kp->arg)); \ + } + +STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, simple_strtoul); +STANDARD_PARAM_DEF(short, short, "%hi", long, simple_strtol); +STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, simple_strtoul); +STANDARD_PARAM_DEF(int, int, "%i", long, simple_strtol); +STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, simple_strtoul); +STANDARD_PARAM_DEF(long, long, "%li", long, simple_strtol); +STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, simple_strtoul); + +int param_set_charp(const char *val, struct kernel_param *kp) +{ + if (!val) { + printk(KERN_ERR "%s: string parameter expected\n", + kp->name); + return -EINVAL; + } + + if (strlen(val) > 1024) { + printk(KERN_ERR "%s: string parameter too long\n", + kp->name); + return -ENOSPC; + } + + *(char **)kp->arg = (char *)val; + return 0; +} + +int param_get_charp(char *buffer, struct kernel_param *kp) +{ + return sprintf(buffer, "%s", *((char **)kp->arg)); +} + +int param_set_bool(const char *val, struct kernel_param *kp) +{ + /* No equals means "set"... */ + if (!val) val = "1"; + + /* One of =[yYnN01] */ + switch (val[0]) { + case 'y': case 'Y': case '1': + *(int *)kp->arg = 1; + return 0; + case 'n': case 'N': case '0': + *(int *)kp->arg = 0; + return 0; + } + return -EINVAL; +} + +int param_get_bool(char *buffer, struct kernel_param *kp) +{ + /* Y and N chosen as being relatively non-coder friendly */ + return sprintf(buffer, "%c", (*(int *)kp->arg) ? 'Y' : 'N'); +} + +int param_set_invbool(const char *val, struct kernel_param *kp) +{ + int boolval, ret; + struct kernel_param dummy = { .arg = &boolval }; + + ret = param_set_bool(val, &dummy); + if (ret == 0) + *(int *)kp->arg = !boolval; + return ret; +} + +int param_get_invbool(char *buffer, struct kernel_param *kp) +{ + int val; + struct kernel_param dummy = { .arg = &val }; + + val = !*(int *)kp->arg; + return param_get_bool(buffer, &dummy); +} + +/* We cheat here and temporarily mangle the string. */ +int param_array(const char *name, + const char *val, + unsigned int min, unsigned int max, + void *elem, int elemsize, + int (*set)(const char *, struct kernel_param *kp), + int *num) +{ + int ret; + struct kernel_param kp; + char save; + + /* Get the name right for errors. */ + kp.name = name; + kp.arg = elem; + + /* No equals sign? */ + if (!val) { + printk(KERN_ERR "%s: expects arguments\n", name); + return -EINVAL; + } + + *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'; + 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; +} + +int param_array_set(const char *val, struct kernel_param *kp) +{ + struct kparam_array *arr = kp->arg; + + return param_array(kp->name, val, 1, arr->max, arr->elem, + arr->elemsize, arr->set, arr->num ?: &arr->max); +} + +int param_array_get(char *buffer, struct kernel_param *kp) +{ + int i, off, ret; + struct kparam_array *arr = kp->arg; + 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; + ret = arr->get(buffer + off, &p); + if (ret < 0) + return ret; + off += ret; + } + buffer[off] = '\0'; + return off; +} + +int param_set_copystring(const char *val, struct kernel_param *kp) +{ + struct kparam_string *kps = kp->arg; + + 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; +} + +int param_get_string(char *buffer, struct kernel_param *kp) +{ + struct kparam_string *kps = kp->arg; + return strlcpy(buffer, kps->string, kps->maxlen); +} + +/* sysfs output in /sys/modules/XYZ/parameters/ */ + +extern struct kernel_param __start___param[], __stop___param[]; + +#define MAX_KBUILD_MODNAME KOBJ_NAME_LEN + +struct param_attribute +{ + struct module_attribute mattr; + struct kernel_param *param; +}; + +struct module_param_attrs +{ + struct attribute_group grp; + struct param_attribute attrs[0]; +}; + +#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->get) + return -EPERM; + + count = attribute->param->get(buf, attribute->param); + 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->set) + return -EPERM; + + err = attribute->param->set(buf, attribute->param); + if (!err) + return len; + return err; +} + +#ifdef CONFIG_MODULES +#define __modinit +#else +#define __modinit __init +#endif + +/* + * param_sysfs_setup - setup sysfs support for one module or KBUILD_MODNAME + * @mk: struct module_kobject (contains parent kobject) + * @kparam: array of struct kernel_param, the actual parameter definitions + * @num_params: number of entries in array + * @name_skip: offset where the parameter name start in kparam[].name. Needed for built-in "modules" + * + * Create a kobject for a (per-module) group of parameters, and create files + * in sysfs. A pointer to the param_kobject is returned on success, + * NULL if there's no parameter to export, or other ERR_PTR(err). + */ +static __modinit struct module_param_attrs * +param_sysfs_setup(struct module_kobject *mk, + struct kernel_param *kparam, + unsigned int num_params, + unsigned int name_skip) +{ + struct module_param_attrs *mp; + unsigned int valid_attrs = 0; + unsigned int i, size[2]; + struct param_attribute *pattr; + struct attribute **gattr; + int err; + + for (i=0; i<num_params; i++) { + if (kparam[i].perm) + valid_attrs++; + } + + if (!valid_attrs) + return NULL; + + size[0] = ALIGN(sizeof(*mp) + + valid_attrs * sizeof(mp->attrs[0]), + sizeof(mp->grp.attrs[0])); + size[1] = (valid_attrs + 1) * sizeof(mp->grp.attrs[0]); + + mp = kmalloc(size[0] + size[1], GFP_KERNEL); + if (!mp) + return ERR_PTR(-ENOMEM); + + mp->grp.name = "parameters"; + mp->grp.attrs = (void *)mp + size[0]; + + pattr = &mp->attrs[0]; + gattr = &mp->grp.attrs[0]; + for (i = 0; i < num_params; i++) { + struct kernel_param *kp = &kparam[i]; + if (kp->perm) { + pattr->param = kp; + pattr->mattr.show = param_attr_show; + pattr->mattr.store = param_attr_store; + pattr->mattr.attr.name = (char *)&kp->name[name_skip]; + pattr->mattr.attr.owner = mk->mod; + pattr->mattr.attr.mode = kp->perm; + *(gattr++) = &(pattr++)->mattr.attr; + } + } + *gattr = NULL; + + if ((err = sysfs_create_group(&mk->kobj, &mp->grp))) { + kfree(mp); + return ERR_PTR(err); + } + return mp; +} + + +#ifdef CONFIG_MODULES + +/* + * 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, and creates a link from + * /sys/module/[mod->name]/parameters to /sys/parameters/[mod->name]/ + */ +int module_param_sysfs_setup(struct module *mod, + struct kernel_param *kparam, + unsigned int num_params) +{ + struct module_param_attrs *mp; + + mp = param_sysfs_setup(&mod->mkobj, kparam, num_params, 0); + if (IS_ERR(mp)) + return PTR_ERR(mp); + + mod->param_attrs = mp; + return 0; +} + +/* + * 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->param_attrs) { + sysfs_remove_group(&mod->mkobj.kobj, + &mod->param_attrs->grp); + /* We are positive that no one is using any param + * attrs at this point. Deallocate immediately. */ + kfree(mod->param_attrs); + mod->param_attrs = NULL; + } +} +#endif + +/* + * kernel_param_sysfs_setup - wrapper for built-in params support + */ +static void __init kernel_param_sysfs_setup(const char *name, + struct kernel_param *kparam, + unsigned int num_params, + unsigned int name_skip) +{ + struct module_kobject *mk; + + mk = kmalloc(sizeof(struct module_kobject), GFP_KERNEL); + memset(mk, 0, sizeof(struct module_kobject)); + + mk->mod = THIS_MODULE; + kobj_set_kset_s(mk, module_subsys); + kobject_set_name(&mk->kobj, name); + kobject_register(&mk->kobj); + + /* no need to keep the kobject if no parameter is exported */ + if (!param_sysfs_setup(mk, kparam, num_params, name_skip)) { + kobject_unregister(&mk->kobj); + kfree(mk); + } +} + +/* + * 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_param_sysfs_setup. + */ +static void __init param_sysfs_builtin(void) +{ + struct kernel_param *kp, *kp_begin = NULL; + unsigned int i, name_len, count = 0; + char modname[MAX_KBUILD_MODNAME + 1] = ""; + + for (i=0; i < __stop___param - __start___param; i++) { + char *dot; + + kp = &__start___param[i]; + + /* We do not handle args without periods. */ + dot = memchr(kp->name, '.', MAX_KBUILD_MODNAME); + if (!dot) { + DEBUGP("couldn't find period in %s\n", kp->name); + continue; + } + name_len = dot - kp->name; + + /* new kbuild_modname? */ + if (strlen(modname) != name_len + || strncmp(modname, kp->name, name_len) != 0) { + /* add a new kobject for previous kernel_params. */ + if (count) + kernel_param_sysfs_setup(modname, + kp_begin, + count, + strlen(modname)+1); + + strncpy(modname, kp->name, name_len); + modname[name_len] = '\0'; + count = 0; + kp_begin = kp; + } + count++; + } + + /* last kernel_params need to be registered as well */ + if (count) + kernel_param_sysfs_setup(modname, kp_begin, count, + strlen(modname)+1); +} + + +/* module-related sysfs stuff */ +#ifdef CONFIG_MODULES + +#define to_module_attr(n) container_of(n, struct module_attribute, attr); +#define to_module_kobject(n) container_of(n, struct module_kobject, kobj); + +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 -EPERM; + + if (!try_module_get(mk->mod)) + return -ENODEV; + + ret = attribute->show(attribute, mk->mod, buf); + + module_put(mk->mod); + + 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 -EPERM; + + if (!try_module_get(mk->mod)) + return -ENODEV; + + ret = attribute->store(attribute, mk->mod, buf, len); + + module_put(mk->mod); + + return ret; +} + +static struct sysfs_ops module_sysfs_ops = { + .show = module_attr_show, + .store = module_attr_store, +}; + +#else +static struct sysfs_ops module_sysfs_ops = { + .show = NULL, + .store = NULL, +}; +#endif + +static struct kobj_type module_ktype = { + .sysfs_ops = &module_sysfs_ops, +}; + +decl_subsys(module, &module_ktype, NULL); + +/* + * param_sysfs_init - wrapper for built-in params support + */ +static int __init param_sysfs_init(void) +{ + subsystem_register(&module_subsys); + + param_sysfs_builtin(); + + return 0; +} +__initcall(param_sysfs_init); + +EXPORT_SYMBOL(param_set_byte); +EXPORT_SYMBOL(param_get_byte); +EXPORT_SYMBOL(param_set_short); +EXPORT_SYMBOL(param_get_short); +EXPORT_SYMBOL(param_set_ushort); +EXPORT_SYMBOL(param_get_ushort); +EXPORT_SYMBOL(param_set_int); +EXPORT_SYMBOL(param_get_int); +EXPORT_SYMBOL(param_set_uint); +EXPORT_SYMBOL(param_get_uint); +EXPORT_SYMBOL(param_set_long); +EXPORT_SYMBOL(param_get_long); +EXPORT_SYMBOL(param_set_ulong); +EXPORT_SYMBOL(param_get_ulong); +EXPORT_SYMBOL(param_set_charp); +EXPORT_SYMBOL(param_get_charp); +EXPORT_SYMBOL(param_set_bool); +EXPORT_SYMBOL(param_get_bool); +EXPORT_SYMBOL(param_set_invbool); +EXPORT_SYMBOL(param_get_invbool); +EXPORT_SYMBOL(param_array_set); +EXPORT_SYMBOL(param_array_get); +EXPORT_SYMBOL(param_set_copystring); +EXPORT_SYMBOL(param_get_string); |