kernel/params.c

   1 /* Helpers for initial module or kernel cmdline parsing
   2    Copyright (C) 2001 Rusty Russell.
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  17 */
  18 #include <linux/moduleparam.h>
  19 #include <linux/kernel.h>
  20 #include <linux/string.h>
  21 #include <linux/errno.h>
  22 #include <linux/module.h>
  23 #include <linux/device.h>
  24 #include <linux/err.h>
  25 #include <linux/slab.h>
  26 #include <linux/ctype.h>
  27
  28 #if 0
  29 #define DEBUGP printk
  30 #else
  31 #define DEBUGP(fmt, a...)
  32 #endif
  33
  34 static inline char dash2underscore(char c)
  35 {
  36         if (c == '-')
  37                 return '_';
  38         return c;
  39 }
  40
  41 static inline int parameq(const char *input, const char *paramname)
  42 {
  43         unsigned int i;
  44         for (i = 0; dash2underscore(input[i]) == paramname[i]; i++)
  45                 if (input[i] == '\0')
  46                         return 1;
  47         return 0;
  48 }
  49
  50 static int parse_one(char *param,
  51                      char *val,
  52                      struct kernel_param *params,
  53                      unsigned num_params,
  54                      int (*handle_unknown)(char *param, char *val))
  55 {
  56         unsigned int i;
  57
  58         /* Find parameter */
  59         for (i = 0; i < num_params; i++) {
  60                 if (parameq(param, params[i].name)) {
  61                         /* Noone handled NULL, so do it here. */
  62                         if (!val && params[i].ops->set != param_set_bool)
  63                                 return -EINVAL;
  64                         DEBUGP("They are equal!  Calling %p\n",
  65                                params[i].ops->set);
  66                         return params[i].ops->set(val, &params[i]);
  67                 }
  68         }
  69
  70         if (handle_unknown) {
  71                 DEBUGP("Unknown argument: calling %p\n", handle_unknown);
  72                 return handle_unknown(param, val);
  73         }
  74
  75         DEBUGP("Unknown argument `%s'\n", param);
  76         return -ENOENT;
  77 }
  78
  79 /* You can use " around spaces, but can't escape ". */
  80 /* Hyphens and underscores equivalent in parameter names. */
  81 static char *next_arg(char *args, char **param, char **val)
  82 {
  83         unsigned int i, equals = 0;
  84         int in_quote = 0, quoted = 0;
  85         char *next;
  86
  87         if (*args == '"') {
  88                 args++;
  89                 in_quote = 1;
  90                 quoted = 1;
  91         }
  92
  93         for (i = 0; args[i]; i++) {
  94                 if (isspace(args[i]) && !in_quote)
  95                         break;
  96                 if (equals == 0) {
  97                         if (args[i] == '=')
  98                                 equals = i;
  99                 }
 100                 if (args[i] == '"')
 101                         in_quote = !in_quote;
 102         }
 103
 104         *param = args;
 105         if (!equals)
 106                 *val = NULL;
 107         else {
 108                 args[equals] = '\0';
 109                 *val = args + equals + 1;
 110
 111                 /* Don't include quotes in value. */
 112                 if (**val == '"') {
 113                         (*val)++;
 114                         if (args[i-1] == '"')
 115                                 args[i-1] = '\0';
 116                 }
 117                 if (quoted && args[i-1] == '"')
 118                         args[i-1] = '\0';
 119         }
 120
 121         if (args[i]) {
 122                 args[i] = '\0';
 123                 next = args + i + 1;
 124         } else
 125                 next = args + i;
 126
 127         /* Chew up trailing spaces. */
 128         return skip_spaces(next);
 129 }
 130
 131 /* Args looks like "foo=bar,bar2 baz=fuz wiz". */
 132 int parse_args(const char *name,
 133                char *args,
 134                struct kernel_param *params,
 135                unsigned num,
 136                int (*unknown)(char *param, char *val))
 137 {
 138         char *param, *val;
 139
 140         DEBUGP("Parsing ARGS: %s\n", args);
 141
 142         /* Chew leading spaces */
 143         args = skip_spaces(args);
 144
 145         while (*args) {
 146                 int ret;
 147                 int irq_was_disabled;
 148
 149                 args = next_arg(args, &param, &val);
 150                 irq_was_disabled = irqs_disabled();
 151                 ret = parse_one(param, val, params, num, unknown);
 152                 if (irq_was_disabled && !irqs_disabled()) {
 153                         printk(KERN_WARNING "parse_args(): option '%s' enabled "
 154                                         "irq's!\n", param);
 155                 }
 156                 switch (ret) {
 157                 case -ENOENT:
 158                         printk(KERN_ERR "%s: Unknown parameter `%s'\n",
 159                                name, param);
 160                         return ret;
 161                 case -ENOSPC:
 162                         printk(KERN_ERR
 163                                "%s: `%s' too large for parameter `%s'\n",
 164                                name, val ?: "", param);
 165                         return ret;
 166                 case 0:
 167                         break;
 168                 default:
 169                         printk(KERN_ERR
 170                                "%s: `%s' invalid for parameter `%s'\n",
 171                                name, val ?: "", param);
 172                         return ret;
 173                 }
 174         }
 175
 176         /* All parsed OK. */
 177         return 0;
 178 }
 179
 180 /* Lazy bastard, eh? */
 181 #define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn)       \
 182         int param_set_##name(const char *val, const struct kernel_param *kp) \
 183         {                                                               \
 184                 tmptype l;                                              \
 185                 int ret;                                                \
 186                                                                         \
 187                 ret = strtolfn(val, 0, &l);                             \
 188                 if (ret == -EINVAL || ((type)l != l))                   \
 189                         return -EINVAL;                                 \
 190                 *((type *)kp->arg) = l;                                 \
 191                 return 0;                                               \
 192         }                                                               \
 193         int param_get_##name(char *buffer, const struct kernel_param *kp) \
 194         {                                                               \
 195                 return sprintf(buffer, format, *((type *)kp->arg));     \
 196         }                                                               \
 197         struct kernel_param_ops param_ops_##name = {                    \
 198                 .set = param_set_##name,                                \
 199                 .get = param_get_##name,                                \
 200         };                                                              \
 201         EXPORT_SYMBOL(param_set_##name);                                \
 202         EXPORT_SYMBOL(param_get_##name);                                \
 203         EXPORT_SYMBOL(param_ops_##name)
 204
 205
 206 STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, strict_strtoul);
 207 STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol);
 208 STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, strict_strtoul);
 209 STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol);
 210 STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, strict_strtoul);
 211 STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol);
 212 STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, strict_strtoul);
 213
 214 int param_set_charp(const char *val, const struct kernel_param *kp)
 215 {
 216         if (strlen(val) > 1024) {
 217                 printk(KERN_ERR "%s: string parameter too long\n",
 218                        kp->name);
 219                 return -ENOSPC;
 220         }
 221
 222         /* This is a hack.  We can't need to strdup in early boot, and we
 223          * don't need to; this mangled commandline is preserved. */
 224         if (slab_is_available()) {
 225                 *(char **)kp->arg = kstrdup(val, GFP_KERNEL);
 226                 if (!*(char **)kp->arg)
 227                         return -ENOMEM;
 228         } else
 229                 *(const char **)kp->arg = val;
 230
 231         return 0;
 232 }
 233 EXPORT_SYMBOL(param_set_charp);
 234
 235 int param_get_charp(char *buffer, const struct kernel_param *kp)
 236 {
 237         return sprintf(buffer, "%s", *((char **)kp->arg));
 238 }
 239 EXPORT_SYMBOL(param_get_charp);
 240
 241 struct kernel_param_ops param_ops_charp = {
 242         .set = param_set_charp,
 243         .get = param_get_charp,
 244 };
 245 EXPORT_SYMBOL(param_ops_charp);
 246
 247 /* Actually could be a bool or an int, for historical reasons. */
 248 int param_set_bool(const char *val, const struct kernel_param *kp)
 249 {
 250         bool v;
 251
 252         /* No equals means "set"... */
 253         if (!val) val = "1";
 254
 255         /* One of =[yYnN01] */
 256         switch (val[0]) {
 257         case 'y': case 'Y': case '1':
 258                 v = true;
 259                 break;
 260         case 'n': case 'N': case '0':
 261                 v = false;
 262                 break;
 263         default:
 264                 return -EINVAL;
 265         }
 266
 267         if (kp->flags & KPARAM_ISBOOL)
 268                 *(bool *)kp->arg = v;
 269         else
 270                 *(int *)kp->arg = v;
 271         return 0;
 272 }
 273 EXPORT_SYMBOL(param_set_bool);
 274
 275 int param_get_bool(char *buffer, const struct kernel_param *kp)
 276 {
 277         bool val;
 278         if (kp->flags & KPARAM_ISBOOL)
 279                 val = *(bool *)kp->arg;
 280         else
 281                 val = *(int *)kp->arg;
 282
 283         /* Y and N chosen as being relatively non-coder friendly */
 284         return sprintf(buffer, "%c", val ? 'Y' : 'N');
 285 }
 286 EXPORT_SYMBOL(param_get_bool);
 287
 288 struct kernel_param_ops param_ops_bool = {
 289         .set = param_set_bool,
 290         .get = param_get_bool,
 291 };
 292 EXPORT_SYMBOL(param_ops_bool);
 293
 294 /* This one must be bool. */
 295 int param_set_invbool(const char *val, const struct kernel_param *kp)
 296 {
 297         int ret;
 298         bool boolval;
 299         struct kernel_param dummy;
 300
 301         dummy.arg = &boolval;
 302         dummy.flags = KPARAM_ISBOOL;
 303         ret = param_set_bool(val, &dummy);
 304         if (ret == 0)
 305                 *(bool *)kp->arg = !boolval;
 306         return ret;
 307 }
 308 EXPORT_SYMBOL(param_set_invbool);
 309
 310 int param_get_invbool(char *buffer, const struct kernel_param *kp)
 311 {
 312         return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y');
 313 }
 314 EXPORT_SYMBOL(param_get_invbool);
 315
 316 struct kernel_param_ops param_ops_invbool = {
 317         .set = param_set_invbool,
 318         .get = param_get_invbool,
 319 };
 320 EXPORT_SYMBOL(param_ops_invbool);
 321
 322 /* We break the rule and mangle the string. */
 323 static int param_array(const char *name,
 324                        const char *val,
 325                        unsigned int min, unsigned int max,
 326                        void *elem, int elemsize,
 327                        int (*set)(const char *, const struct kernel_param *kp),
 328                        u16 flags,
 329                        unsigned int *num)
 330 {
 331         int ret;
 332         struct kernel_param kp;
 333         char save;
 334
 335         /* Get the name right for errors. */
 336         kp.name = name;
 337         kp.arg = elem;
 338         kp.flags = flags;
 339
 340         *num = 0;
 341         /* We expect a comma-separated list of values. */
 342         do {
 343                 int len;
 344
 345                 if (*num == max) {
 346                         printk(KERN_ERR "%s: can only take %i arguments\n",
 347                                name, max);
 348                         return -EINVAL;
 349                 }
 350                 len = strcspn(val, ",");
 351
 352                 /* nul-terminate and parse */
 353                 save = val[len];
 354                 ((char *)val)[len] = '\0';
 355                 ret = set(val, &kp);
 356
 357                 if (ret != 0)
 358                         return ret;
 359                 kp.arg += elemsize;
 360                 val += len+1;
 361                 (*num)++;
 362         } while (save == ',');
 363
 364         if (*num < min) {
 365                 printk(KERN_ERR "%s: needs at least %i arguments\n",
 366                        name, min);
 367                 return -EINVAL;
 368         }
 369         return 0;
 370 }
 371
 372 static int param_array_set(const char *val, const struct kernel_param *kp)
 373 {
 374         const struct kparam_array *arr = kp->arr;
 375         unsigned int temp_num;
 376
 377         return param_array(kp->name, val, 1, arr->max, arr->elem,
 378                            arr->elemsize, arr->ops->set, kp->flags,
 379                            arr->num ?: &temp_num);
 380 }
 381
 382 static int param_array_get(char *buffer, const struct kernel_param *kp)
 383 {
 384         int i, off, ret;
 385         const struct kparam_array *arr = kp->arr;
 386         struct kernel_param p;
 387
 388         p = *kp;
 389         for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
 390                 if (i)
 391                         buffer[off++] = ',';
 392                 p.arg = arr->elem + arr->elemsize * i;
 393                 ret = arr->ops->get(buffer + off, &p);
 394                 if (ret < 0)
 395                         return ret;
 396                 off += ret;
 397         }
 398         buffer[off] = '\0';
 399         return off;
 400 }
 401
 402 struct kernel_param_ops param_array_ops = {
 403         .set = param_array_set,
 404         .get = param_array_get,
 405 };
 406 EXPORT_SYMBOL(param_array_ops);
 407
 408 int param_set_copystring(const char *val, const struct kernel_param *kp)
 409 {
 410         const struct kparam_string *kps = kp->str;
 411
 412         if (strlen(val)+1 > kps->maxlen) {
 413                 printk(KERN_ERR "%s: string doesn't fit in %u chars.\n",
 414                        kp->name, kps->maxlen-1);
 415                 return -ENOSPC;
 416         }
 417         strcpy(kps->string, val);
 418         return 0;
 419 }
 420 EXPORT_SYMBOL(param_set_copystring);
 421
 422 int param_get_string(char *buffer, const struct kernel_param *kp)
 423 {
 424         const struct kparam_string *kps = kp->str;
 425         return strlcpy(buffer, kps->string, kps->maxlen);
 426 }
 427 EXPORT_SYMBOL(param_get_string);
 428
 429 struct kernel_param_ops param_ops_string = {
 430         .set = param_set_copystring,
 431         .get = param_get_string,
 432 };
 433 EXPORT_SYMBOL(param_ops_string);
 434
 435 /* sysfs output in /sys/modules/XYZ/parameters/ */
 436 #define to_module_attr(n) container_of(n, struct module_attribute, attr)
 437 #define to_module_kobject(n) container_of(n, struct module_kobject, kobj)
 438
 439 extern struct kernel_param __start___param[], __stop___param[];
 440
 441 struct param_attribute
 442 {
 443         struct module_attribute mattr;
 444         const struct kernel_param *param;
 445 };
 446
 447 struct module_param_attrs
 448 {
 449         unsigned int num;
 450         struct attribute_group grp;
 451         struct param_attribute attrs[0];
 452 };
 453
 454 #ifdef CONFIG_SYSFS
 455 #define to_param_attr(n) container_of(n, struct param_attribute, mattr)
 456
 457 static ssize_t param_attr_show(struct module_attribute *mattr,
 458                                struct module *mod, char *buf)
 459 {
 460         int count;
 461         struct param_attribute *attribute = to_param_attr(mattr);
 462
 463         if (!attribute->param->ops->get)
 464                 return -EPERM;
 465
 466         count = attribute->param->ops->get(buf, attribute->param);
 467         if (count > 0) {
 468                 strcat(buf, "\n");
 469                 ++count;
 470         }
 471         return count;
 472 }
 473
 474 /* sysfs always hands a nul-terminated string in buf.  We rely on that. */
 475 static ssize_t param_attr_store(struct module_attribute *mattr,
 476                                 struct module *owner,
 477                                 const char *buf, size_t len)
 478 {
 479         int err;
 480         struct param_attribute *attribute = to_param_attr(mattr);
 481
 482         if (!attribute->param->ops->set)
 483                 return -EPERM;
 484
 485         err = attribute->param->ops->set(buf, attribute->param);
 486         if (!err)
 487                 return len;
 488         return err;
 489 }
 490 #endif
 491
 492 #ifdef CONFIG_MODULES
 493 #define __modinit
 494 #else
 495 #define __modinit __init
 496 #endif
 497
 498 #ifdef CONFIG_SYSFS
 499 /*
 500  * add_sysfs_param - add a parameter to sysfs
 501  * @mk: struct module_kobject
 502  * @kparam: the actual parameter definition to add to sysfs
 503  * @name: name of parameter
 504  *
 505  * Create a kobject if for a (per-module) parameter if mp NULL, and
 506  * create file in sysfs.  Returns an error on out of memory.  Always cleans up
 507  * if there's an error.
 508  */
 509 static __modinit int add_sysfs_param(struct module_kobject *mk,
 510                                      const struct kernel_param *kp,
 511                                      const char *name)
 512 {
 513         struct module_param_attrs *new;
 514         struct attribute **attrs;
 515         int err, num;
 516
 517         /* We don't bother calling this with invisible parameters. */
 518         BUG_ON(!kp->perm);
 519
 520         if (!mk->mp) {
 521                 num = 0;
 522                 attrs = NULL;
 523         } else {
 524                 num = mk->mp->num;
 525                 attrs = mk->mp->grp.attrs;
 526         }
 527
 528         /* Enlarge. */
 529         new = krealloc(mk->mp,
 530                        sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1),
 531                        GFP_KERNEL);
 532         if (!new) {
 533                 kfree(mk->mp);
 534                 err = -ENOMEM;
 535                 goto fail;
 536         }
 537         attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL);
 538         if (!attrs) {
 539                 err = -ENOMEM;
 540                 goto fail_free_new;
 541         }
 542
 543         /* Sysfs wants everything zeroed. */
 544         memset(new, 0, sizeof(*new));
 545         memset(&new->attrs[num], 0, sizeof(new->attrs[num]));
 546         memset(&attrs[num], 0, sizeof(attrs[num]));
 547         new->grp.name = "parameters";
 548         new->grp.attrs = attrs;
 549
 550         /* Tack new one on the end. */
 551         sysfs_attr_init(&new->attrs[num].mattr.attr);
 552         new->attrs[num].param = kp;
 553         new->attrs[num].mattr.show = param_attr_show;
 554         new->attrs[num].mattr.store = param_attr_store;
 555         new->attrs[num].mattr.attr.name = (char *)name;
 556         new->attrs[num].mattr.attr.mode = kp->perm;
 557         new->num = num+1;
 558
 559         /* Fix up all the pointers, since krealloc can move us */
 560         for (num = 0; num < new->num; num++)
 561                 new->grp.attrs[num] = &new->attrs[num].mattr.attr;
 562         new->grp.attrs[num] = NULL;
 563
 564         mk->mp = new;
 565         return 0;
 566
 567 fail_free_new:
 568         kfree(new);
 569 fail:
 570         mk->mp = NULL;
 571         return err;
 572 }
 573
 574 #ifdef CONFIG_MODULES
 575 static void free_module_param_attrs(struct module_kobject *mk)
 576 {
 577         kfree(mk->mp->grp.attrs);
 578         kfree(mk->mp);
 579         mk->mp = NULL;
 580 }
 581
 582 /*
 583  * module_param_sysfs_setup - setup sysfs support for one module
 584  * @mod: module
 585  * @kparam: module parameters (array)
 586  * @num_params: number of module parameters
 587  *
 588  * Adds sysfs entries for module parameters under
 589  * /sys/module/[mod->name]/parameters/
 590  */
 591 int module_param_sysfs_setup(struct module *mod,
 592                              const struct kernel_param *kparam,
 593                              unsigned int num_params)
 594 {
 595         int i, err;
 596         bool params = false;
 597
 598         for (i = 0; i < num_params; i++) {
 599                 if (kparam[i].perm == 0)
 600                         continue;
 601                 err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
 602                 if (err)
 603                         return err;
 604                 params = true;
 605         }
 606
 607         if (!params)
 608                 return 0;
 609
 610         /* Create the param group. */
 611         err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
 612         if (err)
 613                 free_module_param_attrs(&mod->mkobj);
 614         return err;
 615 }
 616
 617 /*
 618  * module_param_sysfs_remove - remove sysfs support for one module
 619  * @mod: module
 620  *
 621  * Remove sysfs entries for module parameters and the corresponding
 622  * kobject.
 623  */
 624 void module_param_sysfs_remove(struct module *mod)
 625 {
 626         if (mod->mkobj.mp) {
 627                 sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
 628                 /* We are positive that no one is using any param
 629                  * attrs at this point.  Deallocate immediately. */
 630                 free_module_param_attrs(&mod->mkobj);
 631         }
 632 }
 633 #endif
 634
 635 void destroy_params(const struct kernel_param *params, unsigned num)
 636 {
 637         /* FIXME: This should free kmalloced charp parameters.  It doesn't. */
 638 }
 639
 640 static void __init kernel_add_sysfs_param(const char *name,
 641                                           struct kernel_param *kparam,
 642                                           unsigned int name_skip)
 643 {
 644         struct module_kobject *mk;
 645         struct kobject *kobj;
 646         int err;
 647
 648         kobj = kset_find_obj(module_kset, name);
 649         if (kobj) {
 650                 /* We already have one.  Remove params so we can add more. */
 651                 mk = to_module_kobject(kobj);
 652                 /* We need to remove it before adding parameters. */
 653                 sysfs_remove_group(&mk->kobj, &mk->mp->grp);
 654         } else {
 655                 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
 656                 BUG_ON(!mk);
 657
 658                 mk->mod = THIS_MODULE;
 659                 mk->kobj.kset = module_kset;
 660                 err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
 661                                            "%s", name);
 662                 if (err) {
 663                         kobject_put(&mk->kobj);
 664                         printk(KERN_ERR "Module '%s' failed add to sysfs, "
 665                                "error number %d\n", name, err);
 666                         printk(KERN_ERR "The system will be unstable now.\n");
 667                         return;
 668                 }
 669                 /* So that exit path is even. */
 670                 kobject_get(&mk->kobj);
 671         }
 672
 673         /* These should not fail at boot. */
 674         err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
 675         BUG_ON(err);
 676         err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
 677         BUG_ON(err);
 678         kobject_uevent(&mk->kobj, KOBJ_ADD);
 679         kobject_put(&mk->kobj);
 680 }
 681
 682 /*
 683  * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
 684  *
 685  * Add module_parameters to sysfs for "modules" built into the kernel.
 686  *
 687  * The "module" name (KBUILD_MODNAME) is stored before a dot, the
 688  * "parameter" name is stored behind a dot in kernel_param->name. So,
 689  * extract the "module" name for all built-in kernel_param-eters,
 690  * and for all who have the same, call kernel_add_sysfs_param.
 691  */
 692 static void __init param_sysfs_builtin(void)
 693 {
 694         struct kernel_param *kp;
 695         unsigned int name_len;
 696         char modname[MODULE_NAME_LEN];
 697
 698         for (kp = __start___param; kp < __stop___param; kp++) {
 699                 char *dot;
 700
 701                 if (kp->perm == 0)
 702                         continue;
 703
 704                 dot = strchr(kp->name, '.');
 705                 if (!dot) {
 706                         /* This happens for core_param() */
 707                         strcpy(modname, "kernel");
 708                         name_len = 0;
 709                 } else {
 710                         name_len = dot - kp->name + 1;
 711                         strlcpy(modname, kp->name, name_len);
 712                 }
 713                 kernel_add_sysfs_param(modname, kp, name_len);
 714         }
 715 }
 716
 717
 718 /* module-related sysfs stuff */
 719
 720 static ssize_t module_attr_show(struct kobject *kobj,
 721                                 struct attribute *attr,
 722                                 char *buf)
 723 {
 724         struct module_attribute *attribute;
 725         struct module_kobject *mk;
 726         int ret;
 727
 728         attribute = to_module_attr(attr);
 729         mk = to_module_kobject(kobj);
 730
 731         if (!attribute->show)
 732                 return -EIO;
 733
 734         ret = attribute->show(attribute, mk->mod, buf);
 735
 736         return ret;
 737 }
 738
 739 static ssize_t module_attr_store(struct kobject *kobj,
 740                                 struct attribute *attr,
 741                                 const char *buf, size_t len)
 742 {
 743         struct module_attribute *attribute;
 744         struct module_kobject *mk;
 745         int ret;
 746
 747         attribute = to_module_attr(attr);
 748         mk = to_module_kobject(kobj);
 749
 750         if (!attribute->store)
 751                 return -EIO;
 752
 753         ret = attribute->store(attribute, mk->mod, buf, len);
 754
 755         return ret;
 756 }
 757
 758 static const struct sysfs_ops module_sysfs_ops = {
 759         .show = module_attr_show,
 760         .store = module_attr_store,
 761 };
 762
 763 static int uevent_filter(struct kset *kset, struct kobject *kobj)
 764 {
 765         struct kobj_type *ktype = get_ktype(kobj);
 766
 767         if (ktype == &module_ktype)
 768                 return 1;
 769         return 0;
 770 }
 771
 772 static const struct kset_uevent_ops module_uevent_ops = {
 773         .filter = uevent_filter,
 774 };
 775
 776 struct kset *module_kset;
 777 int module_sysfs_initialized;
 778
 779 struct kobj_type module_ktype = {
 780         .sysfs_ops =    &module_sysfs_ops,
 781 };
 782
 783 /*
 784  * param_sysfs_init - wrapper for built-in params support
 785  */
 786 static int __init param_sysfs_init(void)
 787 {
 788         module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
 789         if (!module_kset) {
 790                 printk(KERN_WARNING "%s (%d): error creating kset\n",
 791                         __FILE__, __LINE__);
 792                 return -ENOMEM;
 793         }
 794         module_sysfs_initialized = 1;
 795
 796         param_sysfs_builtin();
 797
 798         return 0;
 799 }
 800 subsys_initcall(param_sysfs_init);
 801
 802 #endif /* CONFIG_SYSFS */