| 1 | /* |
| 2 | * linux/kernel/resource.c |
| 3 | * |
| 4 | * Copyright (C) 1999 Linus Torvalds |
| 5 | * Copyright (C) 1999 Martin Mares <mj@ucw.cz> |
| 6 | * |
| 7 | * Arbitrary resource management. |
| 8 | */ |
| 9 | |
| 10 | #include <linux/module.h> |
| 11 | #include <linux/errno.h> |
| 12 | #include <linux/ioport.h> |
| 13 | #include <linux/init.h> |
| 14 | #include <linux/slab.h> |
| 15 | #include <linux/spinlock.h> |
| 16 | #include <linux/fs.h> |
| 17 | #include <linux/proc_fs.h> |
| 18 | #include <linux/seq_file.h> |
| 19 | #include <linux/device.h> |
| 20 | #include <linux/pfn.h> |
| 21 | #include <asm/io.h> |
| 22 | |
| 23 | |
| 24 | struct resource ioport_resource = { |
| 25 | .name = "PCI IO", |
| 26 | .start = 0, |
| 27 | .end = IO_SPACE_LIMIT, |
| 28 | .flags = IORESOURCE_IO, |
| 29 | }; |
| 30 | EXPORT_SYMBOL(ioport_resource); |
| 31 | |
| 32 | struct resource iomem_resource = { |
| 33 | .name = "PCI mem", |
| 34 | .start = 0, |
| 35 | .end = -1, |
| 36 | .flags = IORESOURCE_MEM, |
| 37 | }; |
| 38 | EXPORT_SYMBOL(iomem_resource); |
| 39 | |
| 40 | static DEFINE_RWLOCK(resource_lock); |
| 41 | |
| 42 | static void *r_next(struct seq_file *m, void *v, loff_t *pos) |
| 43 | { |
| 44 | struct resource *p = v; |
| 45 | (*pos)++; |
| 46 | if (p->child) |
| 47 | return p->child; |
| 48 | while (!p->sibling && p->parent) |
| 49 | p = p->parent; |
| 50 | return p->sibling; |
| 51 | } |
| 52 | |
| 53 | #ifdef CONFIG_PROC_FS |
| 54 | |
| 55 | enum { MAX_IORES_LEVEL = 5 }; |
| 56 | |
| 57 | static void *r_start(struct seq_file *m, loff_t *pos) |
| 58 | __acquires(resource_lock) |
| 59 | { |
| 60 | struct resource *p = m->private; |
| 61 | loff_t l = 0; |
| 62 | read_lock(&resource_lock); |
| 63 | for (p = p->child; p && l < *pos; p = r_next(m, p, &l)) |
| 64 | ; |
| 65 | return p; |
| 66 | } |
| 67 | |
| 68 | static void r_stop(struct seq_file *m, void *v) |
| 69 | __releases(resource_lock) |
| 70 | { |
| 71 | read_unlock(&resource_lock); |
| 72 | } |
| 73 | |
| 74 | static int r_show(struct seq_file *m, void *v) |
| 75 | { |
| 76 | struct resource *root = m->private; |
| 77 | struct resource *r = v, *p; |
| 78 | int width = root->end < 0x10000 ? 4 : 8; |
| 79 | int depth; |
| 80 | |
| 81 | for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent) |
| 82 | if (p->parent == root) |
| 83 | break; |
| 84 | seq_printf(m, "%*s%0*llx-%0*llx : %s\n", |
| 85 | depth * 2, "", |
| 86 | width, (unsigned long long) r->start, |
| 87 | width, (unsigned long long) r->end, |
| 88 | r->name ? r->name : "<BAD>"); |
| 89 | return 0; |
| 90 | } |
| 91 | |
| 92 | static const struct seq_operations resource_op = { |
| 93 | .start = r_start, |
| 94 | .next = r_next, |
| 95 | .stop = r_stop, |
| 96 | .show = r_show, |
| 97 | }; |
| 98 | |
| 99 | static int ioports_open(struct inode *inode, struct file *file) |
| 100 | { |
| 101 | int res = seq_open(file, &resource_op); |
| 102 | if (!res) { |
| 103 | struct seq_file *m = file->private_data; |
| 104 | m->private = &ioport_resource; |
| 105 | } |
| 106 | return res; |
| 107 | } |
| 108 | |
| 109 | static int iomem_open(struct inode *inode, struct file *file) |
| 110 | { |
| 111 | int res = seq_open(file, &resource_op); |
| 112 | if (!res) { |
| 113 | struct seq_file *m = file->private_data; |
| 114 | m->private = &iomem_resource; |
| 115 | } |
| 116 | return res; |
| 117 | } |
| 118 | |
| 119 | static const struct file_operations proc_ioports_operations = { |
| 120 | .open = ioports_open, |
| 121 | .read = seq_read, |
| 122 | .llseek = seq_lseek, |
| 123 | .release = seq_release, |
| 124 | }; |
| 125 | |
| 126 | static const struct file_operations proc_iomem_operations = { |
| 127 | .open = iomem_open, |
| 128 | .read = seq_read, |
| 129 | .llseek = seq_lseek, |
| 130 | .release = seq_release, |
| 131 | }; |
| 132 | |
| 133 | static int __init ioresources_init(void) |
| 134 | { |
| 135 | proc_create("ioports", 0, NULL, &proc_ioports_operations); |
| 136 | proc_create("iomem", 0, NULL, &proc_iomem_operations); |
| 137 | return 0; |
| 138 | } |
| 139 | __initcall(ioresources_init); |
| 140 | |
| 141 | #endif /* CONFIG_PROC_FS */ |
| 142 | |
| 143 | /* Return the conflict entry if you can't request it */ |
| 144 | static struct resource * __request_resource(struct resource *root, struct resource *new) |
| 145 | { |
| 146 | resource_size_t start = new->start; |
| 147 | resource_size_t end = new->end; |
| 148 | struct resource *tmp, **p; |
| 149 | |
| 150 | if (end < start) |
| 151 | return root; |
| 152 | if (start < root->start) |
| 153 | return root; |
| 154 | if (end > root->end) |
| 155 | return root; |
| 156 | p = &root->child; |
| 157 | for (;;) { |
| 158 | tmp = *p; |
| 159 | if (!tmp || tmp->start > end) { |
| 160 | new->sibling = tmp; |
| 161 | *p = new; |
| 162 | new->parent = root; |
| 163 | return NULL; |
| 164 | } |
| 165 | p = &tmp->sibling; |
| 166 | if (tmp->end < start) |
| 167 | continue; |
| 168 | return tmp; |
| 169 | } |
| 170 | } |
| 171 | |
| 172 | static int __release_resource(struct resource *old) |
| 173 | { |
| 174 | struct resource *tmp, **p; |
| 175 | |
| 176 | p = &old->parent->child; |
| 177 | for (;;) { |
| 178 | tmp = *p; |
| 179 | if (!tmp) |
| 180 | break; |
| 181 | if (tmp == old) { |
| 182 | *p = tmp->sibling; |
| 183 | old->parent = NULL; |
| 184 | return 0; |
| 185 | } |
| 186 | p = &tmp->sibling; |
| 187 | } |
| 188 | return -EINVAL; |
| 189 | } |
| 190 | |
| 191 | /** |
| 192 | * request_resource - request and reserve an I/O or memory resource |
| 193 | * @root: root resource descriptor |
| 194 | * @new: resource descriptor desired by caller |
| 195 | * |
| 196 | * Returns 0 for success, negative error code on error. |
| 197 | */ |
| 198 | int request_resource(struct resource *root, struct resource *new) |
| 199 | { |
| 200 | struct resource *conflict; |
| 201 | |
| 202 | write_lock(&resource_lock); |
| 203 | conflict = __request_resource(root, new); |
| 204 | write_unlock(&resource_lock); |
| 205 | return conflict ? -EBUSY : 0; |
| 206 | } |
| 207 | |
| 208 | EXPORT_SYMBOL(request_resource); |
| 209 | |
| 210 | /** |
| 211 | * release_resource - release a previously reserved resource |
| 212 | * @old: resource pointer |
| 213 | */ |
| 214 | int release_resource(struct resource *old) |
| 215 | { |
| 216 | int retval; |
| 217 | |
| 218 | write_lock(&resource_lock); |
| 219 | retval = __release_resource(old); |
| 220 | write_unlock(&resource_lock); |
| 221 | return retval; |
| 222 | } |
| 223 | |
| 224 | EXPORT_SYMBOL(release_resource); |
| 225 | |
| 226 | #if !defined(CONFIG_ARCH_HAS_WALK_MEMORY) |
| 227 | /* |
| 228 | * Finds the lowest memory reosurce exists within [res->start.res->end) |
| 229 | * the caller must specify res->start, res->end, res->flags and "name". |
| 230 | * If found, returns 0, res is overwritten, if not found, returns -1. |
| 231 | */ |
| 232 | static int find_next_system_ram(struct resource *res, char *name) |
| 233 | { |
| 234 | resource_size_t start, end; |
| 235 | struct resource *p; |
| 236 | |
| 237 | BUG_ON(!res); |
| 238 | |
| 239 | start = res->start; |
| 240 | end = res->end; |
| 241 | BUG_ON(start >= end); |
| 242 | |
| 243 | read_lock(&resource_lock); |
| 244 | for (p = iomem_resource.child; p ; p = p->sibling) { |
| 245 | /* system ram is just marked as IORESOURCE_MEM */ |
| 246 | if (p->flags != res->flags) |
| 247 | continue; |
| 248 | if (name && strcmp(p->name, name)) |
| 249 | continue; |
| 250 | if (p->start > end) { |
| 251 | p = NULL; |
| 252 | break; |
| 253 | } |
| 254 | if ((p->end >= start) && (p->start < end)) |
| 255 | break; |
| 256 | } |
| 257 | read_unlock(&resource_lock); |
| 258 | if (!p) |
| 259 | return -1; |
| 260 | /* copy data */ |
| 261 | if (res->start < p->start) |
| 262 | res->start = p->start; |
| 263 | if (res->end > p->end) |
| 264 | res->end = p->end; |
| 265 | return 0; |
| 266 | } |
| 267 | |
| 268 | /* |
| 269 | * This function calls callback against all memory range of "System RAM" |
| 270 | * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY. |
| 271 | * Now, this function is only for "System RAM". |
| 272 | */ |
| 273 | int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, |
| 274 | void *arg, int (*func)(unsigned long, unsigned long, void *)) |
| 275 | { |
| 276 | struct resource res; |
| 277 | unsigned long pfn, len; |
| 278 | u64 orig_end; |
| 279 | int ret = -1; |
| 280 | |
| 281 | res.start = (u64) start_pfn << PAGE_SHIFT; |
| 282 | res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1; |
| 283 | res.flags = IORESOURCE_MEM | IORESOURCE_BUSY; |
| 284 | orig_end = res.end; |
| 285 | while ((res.start < res.end) && |
| 286 | (find_next_system_ram(&res, "System RAM") >= 0)) { |
| 287 | pfn = (unsigned long)(res.start >> PAGE_SHIFT); |
| 288 | len = (unsigned long)((res.end + 1 - res.start) >> PAGE_SHIFT); |
| 289 | ret = (*func)(pfn, len, arg); |
| 290 | if (ret) |
| 291 | break; |
| 292 | res.start = res.end + 1; |
| 293 | res.end = orig_end; |
| 294 | } |
| 295 | return ret; |
| 296 | } |
| 297 | |
| 298 | #endif |
| 299 | |
| 300 | /* |
| 301 | * Find empty slot in the resource tree given range and alignment. |
| 302 | */ |
| 303 | static int find_resource(struct resource *root, struct resource *new, |
| 304 | resource_size_t size, resource_size_t min, |
| 305 | resource_size_t max, resource_size_t align, |
| 306 | void (*alignf)(void *, struct resource *, |
| 307 | resource_size_t, resource_size_t), |
| 308 | void *alignf_data) |
| 309 | { |
| 310 | struct resource *this = root->child; |
| 311 | struct resource tmp = *new; |
| 312 | |
| 313 | tmp.start = root->start; |
| 314 | /* |
| 315 | * Skip past an allocated resource that starts at 0, since the assignment |
| 316 | * of this->start - 1 to tmp->end below would cause an underflow. |
| 317 | */ |
| 318 | if (this && this->start == 0) { |
| 319 | tmp.start = this->end + 1; |
| 320 | this = this->sibling; |
| 321 | } |
| 322 | for(;;) { |
| 323 | if (this) |
| 324 | tmp.end = this->start - 1; |
| 325 | else |
| 326 | tmp.end = root->end; |
| 327 | if (tmp.start < min) |
| 328 | tmp.start = min; |
| 329 | if (tmp.end > max) |
| 330 | tmp.end = max; |
| 331 | tmp.start = ALIGN(tmp.start, align); |
| 332 | if (alignf) |
| 333 | alignf(alignf_data, &tmp, size, align); |
| 334 | if (tmp.start < tmp.end && tmp.end - tmp.start >= size - 1) { |
| 335 | new->start = tmp.start; |
| 336 | new->end = tmp.start + size - 1; |
| 337 | return 0; |
| 338 | } |
| 339 | if (!this) |
| 340 | break; |
| 341 | tmp.start = this->end + 1; |
| 342 | this = this->sibling; |
| 343 | } |
| 344 | return -EBUSY; |
| 345 | } |
| 346 | |
| 347 | /** |
| 348 | * allocate_resource - allocate empty slot in the resource tree given range & alignment |
| 349 | * @root: root resource descriptor |
| 350 | * @new: resource descriptor desired by caller |
| 351 | * @size: requested resource region size |
| 352 | * @min: minimum size to allocate |
| 353 | * @max: maximum size to allocate |
| 354 | * @align: alignment requested, in bytes |
| 355 | * @alignf: alignment function, optional, called if not NULL |
| 356 | * @alignf_data: arbitrary data to pass to the @alignf function |
| 357 | */ |
| 358 | int allocate_resource(struct resource *root, struct resource *new, |
| 359 | resource_size_t size, resource_size_t min, |
| 360 | resource_size_t max, resource_size_t align, |
| 361 | void (*alignf)(void *, struct resource *, |
| 362 | resource_size_t, resource_size_t), |
| 363 | void *alignf_data) |
| 364 | { |
| 365 | int err; |
| 366 | |
| 367 | write_lock(&resource_lock); |
| 368 | err = find_resource(root, new, size, min, max, align, alignf, alignf_data); |
| 369 | if (err >= 0 && __request_resource(root, new)) |
| 370 | err = -EBUSY; |
| 371 | write_unlock(&resource_lock); |
| 372 | return err; |
| 373 | } |
| 374 | |
| 375 | EXPORT_SYMBOL(allocate_resource); |
| 376 | |
| 377 | /* |
| 378 | * Insert a resource into the resource tree. If successful, return NULL, |
| 379 | * otherwise return the conflicting resource (compare to __request_resource()) |
| 380 | */ |
| 381 | static struct resource * __insert_resource(struct resource *parent, struct resource *new) |
| 382 | { |
| 383 | struct resource *first, *next; |
| 384 | |
| 385 | for (;; parent = first) { |
| 386 | first = __request_resource(parent, new); |
| 387 | if (!first) |
| 388 | return first; |
| 389 | |
| 390 | if (first == parent) |
| 391 | return first; |
| 392 | |
| 393 | if ((first->start > new->start) || (first->end < new->end)) |
| 394 | break; |
| 395 | if ((first->start == new->start) && (first->end == new->end)) |
| 396 | break; |
| 397 | } |
| 398 | |
| 399 | for (next = first; ; next = next->sibling) { |
| 400 | /* Partial overlap? Bad, and unfixable */ |
| 401 | if (next->start < new->start || next->end > new->end) |
| 402 | return next; |
| 403 | if (!next->sibling) |
| 404 | break; |
| 405 | if (next->sibling->start > new->end) |
| 406 | break; |
| 407 | } |
| 408 | |
| 409 | new->parent = parent; |
| 410 | new->sibling = next->sibling; |
| 411 | new->child = first; |
| 412 | |
| 413 | next->sibling = NULL; |
| 414 | for (next = first; next; next = next->sibling) |
| 415 | next->parent = new; |
| 416 | |
| 417 | if (parent->child == first) { |
| 418 | parent->child = new; |
| 419 | } else { |
| 420 | next = parent->child; |
| 421 | while (next->sibling != first) |
| 422 | next = next->sibling; |
| 423 | next->sibling = new; |
| 424 | } |
| 425 | return NULL; |
| 426 | } |
| 427 | |
| 428 | /** |
| 429 | * insert_resource - Inserts a resource in the resource tree |
| 430 | * @parent: parent of the new resource |
| 431 | * @new: new resource to insert |
| 432 | * |
| 433 | * Returns 0 on success, -EBUSY if the resource can't be inserted. |
| 434 | * |
| 435 | * This function is equivalent to request_resource when no conflict |
| 436 | * happens. If a conflict happens, and the conflicting resources |
| 437 | * entirely fit within the range of the new resource, then the new |
| 438 | * resource is inserted and the conflicting resources become children of |
| 439 | * the new resource. |
| 440 | */ |
| 441 | int insert_resource(struct resource *parent, struct resource *new) |
| 442 | { |
| 443 | struct resource *conflict; |
| 444 | |
| 445 | write_lock(&resource_lock); |
| 446 | conflict = __insert_resource(parent, new); |
| 447 | write_unlock(&resource_lock); |
| 448 | return conflict ? -EBUSY : 0; |
| 449 | } |
| 450 | |
| 451 | /** |
| 452 | * insert_resource_expand_to_fit - Insert a resource into the resource tree |
| 453 | * @root: root resource descriptor |
| 454 | * @new: new resource to insert |
| 455 | * |
| 456 | * Insert a resource into the resource tree, possibly expanding it in order |
| 457 | * to make it encompass any conflicting resources. |
| 458 | */ |
| 459 | void insert_resource_expand_to_fit(struct resource *root, struct resource *new) |
| 460 | { |
| 461 | if (new->parent) |
| 462 | return; |
| 463 | |
| 464 | write_lock(&resource_lock); |
| 465 | for (;;) { |
| 466 | struct resource *conflict; |
| 467 | |
| 468 | conflict = __insert_resource(root, new); |
| 469 | if (!conflict) |
| 470 | break; |
| 471 | if (conflict == root) |
| 472 | break; |
| 473 | |
| 474 | /* Ok, expand resource to cover the conflict, then try again .. */ |
| 475 | if (conflict->start < new->start) |
| 476 | new->start = conflict->start; |
| 477 | if (conflict->end > new->end) |
| 478 | new->end = conflict->end; |
| 479 | |
| 480 | printk("Expanded resource %s due to conflict with %s\n", new->name, conflict->name); |
| 481 | } |
| 482 | write_unlock(&resource_lock); |
| 483 | } |
| 484 | |
| 485 | /** |
| 486 | * adjust_resource - modify a resource's start and size |
| 487 | * @res: resource to modify |
| 488 | * @start: new start value |
| 489 | * @size: new size |
| 490 | * |
| 491 | * Given an existing resource, change its start and size to match the |
| 492 | * arguments. Returns 0 on success, -EBUSY if it can't fit. |
| 493 | * Existing children of the resource are assumed to be immutable. |
| 494 | */ |
| 495 | int adjust_resource(struct resource *res, resource_size_t start, resource_size_t size) |
| 496 | { |
| 497 | struct resource *tmp, *parent = res->parent; |
| 498 | resource_size_t end = start + size - 1; |
| 499 | int result = -EBUSY; |
| 500 | |
| 501 | write_lock(&resource_lock); |
| 502 | |
| 503 | if ((start < parent->start) || (end > parent->end)) |
| 504 | goto out; |
| 505 | |
| 506 | for (tmp = res->child; tmp; tmp = tmp->sibling) { |
| 507 | if ((tmp->start < start) || (tmp->end > end)) |
| 508 | goto out; |
| 509 | } |
| 510 | |
| 511 | if (res->sibling && (res->sibling->start <= end)) |
| 512 | goto out; |
| 513 | |
| 514 | tmp = parent->child; |
| 515 | if (tmp != res) { |
| 516 | while (tmp->sibling != res) |
| 517 | tmp = tmp->sibling; |
| 518 | if (start <= tmp->end) |
| 519 | goto out; |
| 520 | } |
| 521 | |
| 522 | res->start = start; |
| 523 | res->end = end; |
| 524 | result = 0; |
| 525 | |
| 526 | out: |
| 527 | write_unlock(&resource_lock); |
| 528 | return result; |
| 529 | } |
| 530 | |
| 531 | static void __init __reserve_region_with_split(struct resource *root, |
| 532 | resource_size_t start, resource_size_t end, |
| 533 | const char *name) |
| 534 | { |
| 535 | struct resource *parent = root; |
| 536 | struct resource *conflict; |
| 537 | struct resource *res = kzalloc(sizeof(*res), GFP_ATOMIC); |
| 538 | |
| 539 | if (!res) |
| 540 | return; |
| 541 | |
| 542 | res->name = name; |
| 543 | res->start = start; |
| 544 | res->end = end; |
| 545 | res->flags = IORESOURCE_BUSY; |
| 546 | |
| 547 | conflict = __request_resource(parent, res); |
| 548 | if (!conflict) |
| 549 | return; |
| 550 | |
| 551 | /* failed, split and try again */ |
| 552 | kfree(res); |
| 553 | |
| 554 | /* conflict covered whole area */ |
| 555 | if (conflict->start <= start && conflict->end >= end) |
| 556 | return; |
| 557 | |
| 558 | if (conflict->start > start) |
| 559 | __reserve_region_with_split(root, start, conflict->start-1, name); |
| 560 | if (conflict->end < end) |
| 561 | __reserve_region_with_split(root, conflict->end+1, end, name); |
| 562 | } |
| 563 | |
| 564 | void __init reserve_region_with_split(struct resource *root, |
| 565 | resource_size_t start, resource_size_t end, |
| 566 | const char *name) |
| 567 | { |
| 568 | write_lock(&resource_lock); |
| 569 | __reserve_region_with_split(root, start, end, name); |
| 570 | write_unlock(&resource_lock); |
| 571 | } |
| 572 | |
| 573 | EXPORT_SYMBOL(adjust_resource); |
| 574 | |
| 575 | /** |
| 576 | * resource_alignment - calculate resource's alignment |
| 577 | * @res: resource pointer |
| 578 | * |
| 579 | * Returns alignment on success, 0 (invalid alignment) on failure. |
| 580 | */ |
| 581 | resource_size_t resource_alignment(struct resource *res) |
| 582 | { |
| 583 | switch (res->flags & (IORESOURCE_SIZEALIGN | IORESOURCE_STARTALIGN)) { |
| 584 | case IORESOURCE_SIZEALIGN: |
| 585 | return resource_size(res); |
| 586 | case IORESOURCE_STARTALIGN: |
| 587 | return res->start; |
| 588 | default: |
| 589 | return 0; |
| 590 | } |
| 591 | } |
| 592 | |
| 593 | /* |
| 594 | * This is compatibility stuff for IO resources. |
| 595 | * |
| 596 | * Note how this, unlike the above, knows about |
| 597 | * the IO flag meanings (busy etc). |
| 598 | * |
| 599 | * request_region creates a new busy region. |
| 600 | * |
| 601 | * check_region returns non-zero if the area is already busy. |
| 602 | * |
| 603 | * release_region releases a matching busy region. |
| 604 | */ |
| 605 | |
| 606 | /** |
| 607 | * __request_region - create a new busy resource region |
| 608 | * @parent: parent resource descriptor |
| 609 | * @start: resource start address |
| 610 | * @n: resource region size |
| 611 | * @name: reserving caller's ID string |
| 612 | * @flags: IO resource flags |
| 613 | */ |
| 614 | struct resource * __request_region(struct resource *parent, |
| 615 | resource_size_t start, resource_size_t n, |
| 616 | const char *name, int flags) |
| 617 | { |
| 618 | struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL); |
| 619 | |
| 620 | if (!res) |
| 621 | return NULL; |
| 622 | |
| 623 | res->name = name; |
| 624 | res->start = start; |
| 625 | res->end = start + n - 1; |
| 626 | res->flags = IORESOURCE_BUSY; |
| 627 | res->flags |= flags; |
| 628 | |
| 629 | write_lock(&resource_lock); |
| 630 | |
| 631 | for (;;) { |
| 632 | struct resource *conflict; |
| 633 | |
| 634 | conflict = __request_resource(parent, res); |
| 635 | if (!conflict) |
| 636 | break; |
| 637 | if (conflict != parent) { |
| 638 | parent = conflict; |
| 639 | if (!(conflict->flags & IORESOURCE_BUSY)) |
| 640 | continue; |
| 641 | } |
| 642 | |
| 643 | /* Uhhuh, that didn't work out.. */ |
| 644 | kfree(res); |
| 645 | res = NULL; |
| 646 | break; |
| 647 | } |
| 648 | write_unlock(&resource_lock); |
| 649 | return res; |
| 650 | } |
| 651 | EXPORT_SYMBOL(__request_region); |
| 652 | |
| 653 | /** |
| 654 | * __check_region - check if a resource region is busy or free |
| 655 | * @parent: parent resource descriptor |
| 656 | * @start: resource start address |
| 657 | * @n: resource region size |
| 658 | * |
| 659 | * Returns 0 if the region is free at the moment it is checked, |
| 660 | * returns %-EBUSY if the region is busy. |
| 661 | * |
| 662 | * NOTE: |
| 663 | * This function is deprecated because its use is racy. |
| 664 | * Even if it returns 0, a subsequent call to request_region() |
| 665 | * may fail because another driver etc. just allocated the region. |
| 666 | * Do NOT use it. It will be removed from the kernel. |
| 667 | */ |
| 668 | int __check_region(struct resource *parent, resource_size_t start, |
| 669 | resource_size_t n) |
| 670 | { |
| 671 | struct resource * res; |
| 672 | |
| 673 | res = __request_region(parent, start, n, "check-region", 0); |
| 674 | if (!res) |
| 675 | return -EBUSY; |
| 676 | |
| 677 | release_resource(res); |
| 678 | kfree(res); |
| 679 | return 0; |
| 680 | } |
| 681 | EXPORT_SYMBOL(__check_region); |
| 682 | |
| 683 | /** |
| 684 | * __release_region - release a previously reserved resource region |
| 685 | * @parent: parent resource descriptor |
| 686 | * @start: resource start address |
| 687 | * @n: resource region size |
| 688 | * |
| 689 | * The described resource region must match a currently busy region. |
| 690 | */ |
| 691 | void __release_region(struct resource *parent, resource_size_t start, |
| 692 | resource_size_t n) |
| 693 | { |
| 694 | struct resource **p; |
| 695 | resource_size_t end; |
| 696 | |
| 697 | p = &parent->child; |
| 698 | end = start + n - 1; |
| 699 | |
| 700 | write_lock(&resource_lock); |
| 701 | |
| 702 | for (;;) { |
| 703 | struct resource *res = *p; |
| 704 | |
| 705 | if (!res) |
| 706 | break; |
| 707 | if (res->start <= start && res->end >= end) { |
| 708 | if (!(res->flags & IORESOURCE_BUSY)) { |
| 709 | p = &res->child; |
| 710 | continue; |
| 711 | } |
| 712 | if (res->start != start || res->end != end) |
| 713 | break; |
| 714 | *p = res->sibling; |
| 715 | write_unlock(&resource_lock); |
| 716 | kfree(res); |
| 717 | return; |
| 718 | } |
| 719 | p = &res->sibling; |
| 720 | } |
| 721 | |
| 722 | write_unlock(&resource_lock); |
| 723 | |
| 724 | printk(KERN_WARNING "Trying to free nonexistent resource " |
| 725 | "<%016llx-%016llx>\n", (unsigned long long)start, |
| 726 | (unsigned long long)end); |
| 727 | } |
| 728 | EXPORT_SYMBOL(__release_region); |
| 729 | |
| 730 | /* |
| 731 | * Managed region resource |
| 732 | */ |
| 733 | struct region_devres { |
| 734 | struct resource *parent; |
| 735 | resource_size_t start; |
| 736 | resource_size_t n; |
| 737 | }; |
| 738 | |
| 739 | static void devm_region_release(struct device *dev, void *res) |
| 740 | { |
| 741 | struct region_devres *this = res; |
| 742 | |
| 743 | __release_region(this->parent, this->start, this->n); |
| 744 | } |
| 745 | |
| 746 | static int devm_region_match(struct device *dev, void *res, void *match_data) |
| 747 | { |
| 748 | struct region_devres *this = res, *match = match_data; |
| 749 | |
| 750 | return this->parent == match->parent && |
| 751 | this->start == match->start && this->n == match->n; |
| 752 | } |
| 753 | |
| 754 | struct resource * __devm_request_region(struct device *dev, |
| 755 | struct resource *parent, resource_size_t start, |
| 756 | resource_size_t n, const char *name) |
| 757 | { |
| 758 | struct region_devres *dr = NULL; |
| 759 | struct resource *res; |
| 760 | |
| 761 | dr = devres_alloc(devm_region_release, sizeof(struct region_devres), |
| 762 | GFP_KERNEL); |
| 763 | if (!dr) |
| 764 | return NULL; |
| 765 | |
| 766 | dr->parent = parent; |
| 767 | dr->start = start; |
| 768 | dr->n = n; |
| 769 | |
| 770 | res = __request_region(parent, start, n, name, 0); |
| 771 | if (res) |
| 772 | devres_add(dev, dr); |
| 773 | else |
| 774 | devres_free(dr); |
| 775 | |
| 776 | return res; |
| 777 | } |
| 778 | EXPORT_SYMBOL(__devm_request_region); |
| 779 | |
| 780 | void __devm_release_region(struct device *dev, struct resource *parent, |
| 781 | resource_size_t start, resource_size_t n) |
| 782 | { |
| 783 | struct region_devres match_data = { parent, start, n }; |
| 784 | |
| 785 | __release_region(parent, start, n); |
| 786 | WARN_ON(devres_destroy(dev, devm_region_release, devm_region_match, |
| 787 | &match_data)); |
| 788 | } |
| 789 | EXPORT_SYMBOL(__devm_release_region); |
| 790 | |
| 791 | /* |
| 792 | * Called from init/main.c to reserve IO ports. |
| 793 | */ |
| 794 | #define MAXRESERVE 4 |
| 795 | static int __init reserve_setup(char *str) |
| 796 | { |
| 797 | static int reserved; |
| 798 | static struct resource reserve[MAXRESERVE]; |
| 799 | |
| 800 | for (;;) { |
| 801 | unsigned int io_start, io_num; |
| 802 | int x = reserved; |
| 803 | |
| 804 | if (get_option (&str, &io_start) != 2) |
| 805 | break; |
| 806 | if (get_option (&str, &io_num) == 0) |
| 807 | break; |
| 808 | if (x < MAXRESERVE) { |
| 809 | struct resource *res = reserve + x; |
| 810 | res->name = "reserved"; |
| 811 | res->start = io_start; |
| 812 | res->end = io_start + io_num - 1; |
| 813 | res->flags = IORESOURCE_BUSY; |
| 814 | res->child = NULL; |
| 815 | if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, res) == 0) |
| 816 | reserved = x+1; |
| 817 | } |
| 818 | } |
| 819 | return 1; |
| 820 | } |
| 821 | |
| 822 | __setup("reserve=", reserve_setup); |
| 823 | |
| 824 | /* |
| 825 | * Check if the requested addr and size spans more than any slot in the |
| 826 | * iomem resource tree. |
| 827 | */ |
| 828 | int iomem_map_sanity_check(resource_size_t addr, unsigned long size) |
| 829 | { |
| 830 | struct resource *p = &iomem_resource; |
| 831 | int err = 0; |
| 832 | loff_t l; |
| 833 | |
| 834 | read_lock(&resource_lock); |
| 835 | for (p = p->child; p ; p = r_next(NULL, p, &l)) { |
| 836 | /* |
| 837 | * We can probably skip the resources without |
| 838 | * IORESOURCE_IO attribute? |
| 839 | */ |
| 840 | if (p->start >= addr + size) |
| 841 | continue; |
| 842 | if (p->end < addr) |
| 843 | continue; |
| 844 | if (PFN_DOWN(p->start) <= PFN_DOWN(addr) && |
| 845 | PFN_DOWN(p->end) >= PFN_DOWN(addr + size - 1)) |
| 846 | continue; |
| 847 | /* |
| 848 | * if a resource is "BUSY", it's not a hardware resource |
| 849 | * but a driver mapping of such a resource; we don't want |
| 850 | * to warn for those; some drivers legitimately map only |
| 851 | * partial hardware resources. (example: vesafb) |
| 852 | */ |
| 853 | if (p->flags & IORESOURCE_BUSY) |
| 854 | continue; |
| 855 | |
| 856 | printk(KERN_WARNING "resource map sanity check conflict: " |
| 857 | "0x%llx 0x%llx 0x%llx 0x%llx %s\n", |
| 858 | (unsigned long long)addr, |
| 859 | (unsigned long long)(addr + size - 1), |
| 860 | (unsigned long long)p->start, |
| 861 | (unsigned long long)p->end, |
| 862 | p->name); |
| 863 | err = -1; |
| 864 | break; |
| 865 | } |
| 866 | read_unlock(&resource_lock); |
| 867 | |
| 868 | return err; |
| 869 | } |
| 870 | |
| 871 | #ifdef CONFIG_STRICT_DEVMEM |
| 872 | static int strict_iomem_checks = 1; |
| 873 | #else |
| 874 | static int strict_iomem_checks; |
| 875 | #endif |
| 876 | |
| 877 | /* |
| 878 | * check if an address is reserved in the iomem resource tree |
| 879 | * returns 1 if reserved, 0 if not reserved. |
| 880 | */ |
| 881 | int iomem_is_exclusive(u64 addr) |
| 882 | { |
| 883 | struct resource *p = &iomem_resource; |
| 884 | int err = 0; |
| 885 | loff_t l; |
| 886 | int size = PAGE_SIZE; |
| 887 | |
| 888 | if (!strict_iomem_checks) |
| 889 | return 0; |
| 890 | |
| 891 | addr = addr & PAGE_MASK; |
| 892 | |
| 893 | read_lock(&resource_lock); |
| 894 | for (p = p->child; p ; p = r_next(NULL, p, &l)) { |
| 895 | /* |
| 896 | * We can probably skip the resources without |
| 897 | * IORESOURCE_IO attribute? |
| 898 | */ |
| 899 | if (p->start >= addr + size) |
| 900 | break; |
| 901 | if (p->end < addr) |
| 902 | continue; |
| 903 | if (p->flags & IORESOURCE_BUSY && |
| 904 | p->flags & IORESOURCE_EXCLUSIVE) { |
| 905 | err = 1; |
| 906 | break; |
| 907 | } |
| 908 | } |
| 909 | read_unlock(&resource_lock); |
| 910 | |
| 911 | return err; |
| 912 | } |
| 913 | |
| 914 | static int __init strict_iomem(char *str) |
| 915 | { |
| 916 | if (strstr(str, "relaxed")) |
| 917 | strict_iomem_checks = 0; |
| 918 | if (strstr(str, "strict")) |
| 919 | strict_iomem_checks = 1; |
| 920 | return 1; |
| 921 | } |
| 922 | |
| 923 | __setup("iomem=", strict_iomem); |