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/sched.h> 19#include <linux/seq_file.h> 20#include <linux/device.h> 21#include <linux/pfn.h> 22#include <asm/io.h> 23 24 25struct resource ioport_resource = { 26 .name = "PCI IO", 27 .start = 0, 28 .end = IO_SPACE_LIMIT, 29 .flags = IORESOURCE_IO, 30}; 31EXPORT_SYMBOL(ioport_resource); 32 33struct resource iomem_resource = { 34 .name = "PCI mem", 35 .start = 0, 36 .end = -1, 37 .flags = IORESOURCE_MEM, 38}; 39EXPORT_SYMBOL(iomem_resource); 40 41static DEFINE_RWLOCK(resource_lock); 42 43static void *r_next(struct seq_file *m, void *v, loff_t *pos) 44{ 45 struct resource *p = v; 46 (*pos)++; 47 if (p->child) 48 return p->child; 49 while (!p->sibling && p->parent) 50 p = p->parent; 51 return p->sibling; 52} 53 54#ifdef CONFIG_PROC_FS 55 56enum { MAX_IORES_LEVEL = 5 }; 57 58static void *r_start(struct seq_file *m, loff_t *pos) 59 __acquires(resource_lock) 60{ 61 struct resource *p = m->private; 62 loff_t l = 0; 63 read_lock(&resource_lock); 64 for (p = p->child; p && l < *pos; p = r_next(m, p, &l)) 65 ; 66 return p; 67} 68 69static void r_stop(struct seq_file *m, void *v) 70 __releases(resource_lock) 71{ 72 read_unlock(&resource_lock); 73} 74 75static int r_show(struct seq_file *m, void *v) 76{ 77 struct resource *root = m->private; 78 struct resource *r = v, *p; 79 int width = root->end < 0x10000 ? 4 : 8; 80 int depth; 81 82 for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent) 83 if (p->parent == root) 84 break; 85 seq_printf(m, "%*s%0*llx-%0*llx : %s\n", 86 depth * 2, "", 87 width, (unsigned long long) r->start, 88 width, (unsigned long long) r->end, 89 r->name ? r->name : "<BAD>"); 90 return 0; 91} 92 93static const struct seq_operations resource_op = { 94 .start = r_start, 95 .next = r_next, 96 .stop = r_stop, 97 .show = r_show, 98}; 99 100static int ioports_open(struct inode *inode, struct file *file) 101{ 102 int res = seq_open(file, &resource_op); 103 if (!res) { 104 struct seq_file *m = file->private_data; 105 m->private = &ioport_resource; 106 } 107 return res; 108} 109 110static int iomem_open(struct inode *inode, struct file *file) 111{ 112 int res = seq_open(file, &resource_op); 113 if (!res) { 114 struct seq_file *m = file->private_data; 115 m->private = &iomem_resource; 116 } 117 return res; 118} 119 120static const struct file_operations proc_ioports_operations = { 121 .open = ioports_open, 122 .read = seq_read, 123 .llseek = seq_lseek, 124 .release = seq_release, 125}; 126 127static const struct file_operations proc_iomem_operations = { 128 .open = iomem_open, 129 .read = seq_read, 130 .llseek = seq_lseek, 131 .release = seq_release, 132}; 133 134static int __init ioresources_init(void) 135{ 136 proc_create("ioports", 0, NULL, &proc_ioports_operations); 137 proc_create("iomem", 0, NULL, &proc_iomem_operations); 138 return 0; 139} 140__initcall(ioresources_init); 141 142#endif /* CONFIG_PROC_FS */ 143 144/* Return the conflict entry if you can't request it */ 145static struct resource * __request_resource(struct resource *root, struct resource *new) 146{ 147 resource_size_t start = new->start; 148 resource_size_t end = new->end; 149 struct resource *tmp, **p; 150 151 if (end < start) 152 return root; 153 if (start < root->start) 154 return root; 155 if (end > root->end) 156 return root; 157 p = &root->child; 158 for (;;) { 159 tmp = *p; 160 if (!tmp || tmp->start > end) { 161 new->sibling = tmp; 162 *p = new; 163 new->parent = root; 164 return NULL; 165 } 166 p = &tmp->sibling; 167 if (tmp->end < start) 168 continue; 169 return tmp; 170 } 171} 172 173static int __release_resource(struct resource *old) 174{ 175 struct resource *tmp, **p; 176 177 p = &old->parent->child; 178 for (;;) { 179 tmp = *p; 180 if (!tmp) 181 break; 182 if (tmp == old) { 183 *p = tmp->sibling; 184 old->parent = NULL; 185 return 0; 186 } 187 p = &tmp->sibling; 188 } 189 return -EINVAL; 190} 191 192static void __release_child_resources(struct resource *r) 193{ 194 struct resource *tmp, *p; 195 resource_size_t size; 196 197 p = r->child; 198 r->child = NULL; 199 while (p) { 200 tmp = p; 201 p = p->sibling; 202 203 tmp->parent = NULL; 204 tmp->sibling = NULL; 205 __release_child_resources(tmp); 206 207 printk(KERN_DEBUG "release child resource %pR\n", tmp); 208 /* need to restore size, and keep flags */ 209 size = resource_size(tmp); 210 tmp->start = 0; 211 tmp->end = size - 1; 212 } 213} 214 215void release_child_resources(struct resource *r) 216{ 217 write_lock(&resource_lock); 218 __release_child_resources(r); 219 write_unlock(&resource_lock); 220} 221 222/** 223 * request_resource_conflict - request and reserve an I/O or memory resource 224 * @root: root resource descriptor 225 * @new: resource descriptor desired by caller 226 * 227 * Returns 0 for success, conflict resource on error. 228 */ 229struct resource *request_resource_conflict(struct resource *root, struct resource *new) 230{ 231 struct resource *conflict; 232 233 write_lock(&resource_lock); 234 conflict = __request_resource(root, new); 235 write_unlock(&resource_lock); 236 return conflict; 237} 238 239/** 240 * request_resource - request and reserve an I/O or memory resource 241 * @root: root resource descriptor 242 * @new: resource descriptor desired by caller 243 * 244 * Returns 0 for success, negative error code on error. 245 */ 246int request_resource(struct resource *root, struct resource *new) 247{ 248 struct resource *conflict; 249 250 conflict = request_resource_conflict(root, new); 251 return conflict ? -EBUSY : 0; 252} 253 254EXPORT_SYMBOL(request_resource); 255 256/** 257 * release_resource - release a previously reserved resource 258 * @old: resource pointer 259 */ 260int release_resource(struct resource *old) 261{ 262 int retval; 263 264 write_lock(&resource_lock); 265 retval = __release_resource(old); 266 write_unlock(&resource_lock); 267 return retval; 268} 269 270EXPORT_SYMBOL(release_resource); 271 272#if !defined(CONFIG_ARCH_HAS_WALK_MEMORY) 273/* 274 * Finds the lowest memory reosurce exists within [res->start.res->end) 275 * the caller must specify res->start, res->end, res->flags and "name". 276 * If found, returns 0, res is overwritten, if not found, returns -1. 277 */ 278static int find_next_system_ram(struct resource *res, char *name) 279{ 280 resource_size_t start, end; 281 struct resource *p; 282 283 BUG_ON(!res); 284 285 start = res->start; 286 end = res->end; 287 BUG_ON(start >= end); 288 289 read_lock(&resource_lock); 290 for (p = iomem_resource.child; p ; p = p->sibling) { 291 /* system ram is just marked as IORESOURCE_MEM */ 292 if (p->flags != res->flags) 293 continue; 294 if (name && strcmp(p->name, name)) 295 continue; 296 if (p->start > end) { 297 p = NULL; 298 break; 299 } 300 if ((p->end >= start) && (p->start < end)) 301 break; 302 } 303 read_unlock(&resource_lock); 304 if (!p) 305 return -1; 306 /* copy data */ 307 if (res->start < p->start) 308 res->start = p->start; 309 if (res->end > p->end) 310 res->end = p->end; 311 return 0; 312} 313 314/* 315 * This function calls callback against all memory range of "System RAM" 316 * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY. 317 * Now, this function is only for "System RAM". 318 */ 319int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, 320 void *arg, int (*func)(unsigned long, unsigned long, void *)) 321{ 322 struct resource res; 323 unsigned long pfn, end_pfn; 324 u64 orig_end; 325 int ret = -1; 326 327 res.start = (u64) start_pfn << PAGE_SHIFT; 328 res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1; 329 res.flags = IORESOURCE_MEM | IORESOURCE_BUSY; 330 orig_end = res.end; 331 while ((res.start < res.end) && 332 (find_next_system_ram(&res, "System RAM") >= 0)) { 333 pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT; 334 end_pfn = (res.end + 1) >> PAGE_SHIFT; 335 if (end_pfn > pfn) 336 ret = (*func)(pfn, end_pfn - pfn, arg); 337 if (ret) 338 break; 339 res.start = res.end + 1; 340 res.end = orig_end; 341 } 342 return ret; 343} 344 345#endif 346 347static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg) 348{ 349 return 1; 350} 351/* 352 * This generic page_is_ram() returns true if specified address is 353 * registered as "System RAM" in iomem_resource list. 354 */ 355int __weak page_is_ram(unsigned long pfn) 356{ 357 return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1; 358} 359 360/* 361 * Find empty slot in the resource tree given range and alignment. 362 */ 363static int find_resource(struct resource *root, struct resource *new, 364 resource_size_t size, resource_size_t min, 365 resource_size_t max, resource_size_t align, 366 resource_size_t (*alignf)(void *, 367 const struct resource *, 368 resource_size_t, 369 resource_size_t), 370 void *alignf_data) 371{ 372 struct resource *this = root->child; 373 struct resource tmp = *new; 374 375 tmp.start = root->start; 376 /* 377 * Skip past an allocated resource that starts at 0, since the assignment 378 * of this->start - 1 to tmp->end below would cause an underflow. 379 */ 380 if (this && this->start == 0) { 381 tmp.start = this->end + 1; 382 this = this->sibling; 383 } 384 for(;;) { 385 if (this) 386 tmp.end = this->start - 1; 387 else 388 tmp.end = root->end; 389 if (tmp.start < min) 390 tmp.start = min; 391 if (tmp.end > max) 392 tmp.end = max; 393 tmp.start = ALIGN(tmp.start, align); 394 if (alignf) 395 tmp.start = alignf(alignf_data, &tmp, size, align); 396 if (tmp.start < tmp.end && tmp.end - tmp.start >= size - 1) { 397 new->start = tmp.start; 398 new->end = tmp.start + size - 1; 399 return 0; 400 } 401 if (!this) 402 break; 403 tmp.start = this->end + 1; 404 this = this->sibling; 405 } 406 return -EBUSY; 407} 408 409/** 410 * allocate_resource - allocate empty slot in the resource tree given range & alignment 411 * @root: root resource descriptor 412 * @new: resource descriptor desired by caller 413 * @size: requested resource region size 414 * @min: minimum size to allocate 415 * @max: maximum size to allocate 416 * @align: alignment requested, in bytes 417 * @alignf: alignment function, optional, called if not NULL 418 * @alignf_data: arbitrary data to pass to the @alignf function 419 */ 420int allocate_resource(struct resource *root, struct resource *new, 421 resource_size_t size, resource_size_t min, 422 resource_size_t max, resource_size_t align, 423 resource_size_t (*alignf)(void *, 424 const struct resource *, 425 resource_size_t, 426 resource_size_t), 427 void *alignf_data) 428{ 429 int err; 430 431 write_lock(&resource_lock); 432 err = find_resource(root, new, size, min, max, align, alignf, alignf_data); 433 if (err >= 0 && __request_resource(root, new)) 434 err = -EBUSY; 435 write_unlock(&resource_lock); 436 return err; 437} 438 439EXPORT_SYMBOL(allocate_resource); 440 441/* 442 * Insert a resource into the resource tree. If successful, return NULL, 443 * otherwise return the conflicting resource (compare to __request_resource()) 444 */ 445static struct resource * __insert_resource(struct resource *parent, struct resource *new) 446{ 447 struct resource *first, *next; 448 449 for (;; parent = first) { 450 first = __request_resource(parent, new); 451 if (!first) 452 return first; 453 454 if (first == parent) 455 return first; 456 457 if ((first->start > new->start) || (first->end < new->end)) 458 break; 459 if ((first->start == new->start) && (first->end == new->end)) 460 break; 461 } 462 463 for (next = first; ; next = next->sibling) { 464 /* Partial overlap? Bad, and unfixable */ 465 if (next->start < new->start || next->end > new->end) 466 return next; 467 if (!next->sibling) 468 break; 469 if (next->sibling->start > new->end) 470 break; 471 } 472 473 new->parent = parent; 474 new->sibling = next->sibling; 475 new->child = first; 476 477 next->sibling = NULL; 478 for (next = first; next; next = next->sibling) 479 next->parent = new; 480 481 if (parent->child == first) { 482 parent->child = new; 483 } else { 484 next = parent->child; 485 while (next->sibling != first) 486 next = next->sibling; 487 next->sibling = new; 488 } 489 return NULL; 490} 491 492/** 493 * insert_resource_conflict - Inserts resource in the resource tree 494 * @parent: parent of the new resource 495 * @new: new resource to insert 496 * 497 * Returns 0 on success, conflict resource if the resource can't be inserted. 498 * 499 * This function is equivalent to request_resource_conflict when no conflict 500 * happens. If a conflict happens, and the conflicting resources 501 * entirely fit within the range of the new resource, then the new 502 * resource is inserted and the conflicting resources become children of 503 * the new resource. 504 */ 505struct resource *insert_resource_conflict(struct resource *parent, struct resource *new) 506{ 507 struct resource *conflict; 508 509 write_lock(&resource_lock); 510 conflict = __insert_resource(parent, new); 511 write_unlock(&resource_lock); 512 return conflict; 513} 514 515/** 516 * insert_resource - Inserts a resource in the resource tree 517 * @parent: parent of the new resource 518 * @new: new resource to insert 519 * 520 * Returns 0 on success, -EBUSY if the resource can't be inserted. 521 */ 522int insert_resource(struct resource *parent, struct resource *new) 523{ 524 struct resource *conflict; 525 526 conflict = insert_resource_conflict(parent, new); 527 return conflict ? -EBUSY : 0; 528} 529 530/** 531 * insert_resource_expand_to_fit - Insert a resource into the resource tree 532 * @root: root resource descriptor 533 * @new: new resource to insert 534 * 535 * Insert a resource into the resource tree, possibly expanding it in order 536 * to make it encompass any conflicting resources. 537 */ 538void insert_resource_expand_to_fit(struct resource *root, struct resource *new) 539{ 540 if (new->parent) 541 return; 542 543 write_lock(&resource_lock); 544 for (;;) { 545 struct resource *conflict; 546 547 conflict = __insert_resource(root, new); 548 if (!conflict) 549 break; 550 if (conflict == root) 551 break; 552 553 /* Ok, expand resource to cover the conflict, then try again .. */ 554 if (conflict->start < new->start) 555 new->start = conflict->start; 556 if (conflict->end > new->end) 557 new->end = conflict->end; 558 559 printk("Expanded resource %s due to conflict with %s\n", new->name, conflict->name); 560 } 561 write_unlock(&resource_lock); 562} 563 564/** 565 * adjust_resource - modify a resource's start and size 566 * @res: resource to modify 567 * @start: new start value 568 * @size: new size 569 * 570 * Given an existing resource, change its start and size to match the 571 * arguments. Returns 0 on success, -EBUSY if it can't fit. 572 * Existing children of the resource are assumed to be immutable. 573 */ 574int adjust_resource(struct resource *res, resource_size_t start, resource_size_t size) 575{ 576 struct resource *tmp, *parent = res->parent; 577 resource_size_t end = start + size - 1; 578 int result = -EBUSY; 579 580 write_lock(&resource_lock); 581 582 if ((start < parent->start) || (end > parent->end)) 583 goto out; 584 585 for (tmp = res->child; tmp; tmp = tmp->sibling) { 586 if ((tmp->start < start) || (tmp->end > end)) 587 goto out; 588 } 589 590 if (res->sibling && (res->sibling->start <= end)) 591 goto out; 592 593 tmp = parent->child; 594 if (tmp != res) { 595 while (tmp->sibling != res) 596 tmp = tmp->sibling; 597 if (start <= tmp->end) 598 goto out; 599 } 600 601 res->start = start; 602 res->end = end; 603 result = 0; 604 605 out: 606 write_unlock(&resource_lock); 607 return result; 608} 609 610static void __init __reserve_region_with_split(struct resource *root, 611 resource_size_t start, resource_size_t end, 612 const char *name) 613{ 614 struct resource *parent = root; 615 struct resource *conflict; 616 struct resource *res = kzalloc(sizeof(*res), GFP_ATOMIC); 617 618 if (!res) 619 return; 620 621 res->name = name; 622 res->start = start; 623 res->end = end; 624 res->flags = IORESOURCE_BUSY; 625 626 conflict = __request_resource(parent, res); 627 if (!conflict) 628 return; 629 630 /* failed, split and try again */ 631 kfree(res); 632 633 /* conflict covered whole area */ 634 if (conflict->start <= start && conflict->end >= end) 635 return; 636 637 if (conflict->start > start) 638 __reserve_region_with_split(root, start, conflict->start-1, name); 639 if (conflict->end < end) 640 __reserve_region_with_split(root, conflict->end+1, end, name); 641} 642 643void __init reserve_region_with_split(struct resource *root, 644 resource_size_t start, resource_size_t end, 645 const char *name) 646{ 647 write_lock(&resource_lock); 648 __reserve_region_with_split(root, start, end, name); 649 write_unlock(&resource_lock); 650} 651 652EXPORT_SYMBOL(adjust_resource); 653 654/** 655 * resource_alignment - calculate resource's alignment 656 * @res: resource pointer 657 * 658 * Returns alignment on success, 0 (invalid alignment) on failure. 659 */ 660resource_size_t resource_alignment(struct resource *res) 661{ 662 switch (res->flags & (IORESOURCE_SIZEALIGN | IORESOURCE_STARTALIGN)) { 663 case IORESOURCE_SIZEALIGN: 664 return resource_size(res); 665 case IORESOURCE_STARTALIGN: 666 return res->start; 667 default: 668 return 0; 669 } 670} 671 672/* 673 * This is compatibility stuff for IO resources. 674 * 675 * Note how this, unlike the above, knows about 676 * the IO flag meanings (busy etc). 677 * 678 * request_region creates a new busy region. 679 * 680 * check_region returns non-zero if the area is already busy. 681 * 682 * release_region releases a matching busy region. 683 */ 684 685static DECLARE_WAIT_QUEUE_HEAD(muxed_resource_wait); 686 687/** 688 * __request_region - create a new busy resource region 689 * @parent: parent resource descriptor 690 * @start: resource start address 691 * @n: resource region size 692 * @name: reserving caller's ID string 693 * @flags: IO resource flags 694 */ 695struct resource * __request_region(struct resource *parent, 696 resource_size_t start, resource_size_t n, 697 const char *name, int flags) 698{ 699 DECLARE_WAITQUEUE(wait, current); 700 struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL); 701 702 if (!res) 703 return NULL; 704 705 res->name = name; 706 res->start = start; 707 res->end = start + n - 1; 708 res->flags = IORESOURCE_BUSY; 709 res->flags |= flags; 710 711 write_lock(&resource_lock); 712 713 for (;;) { 714 struct resource *conflict; 715 716 conflict = __request_resource(parent, res); 717 if (!conflict) 718 break; 719 if (conflict != parent) { 720 parent = conflict; 721 if (!(conflict->flags & IORESOURCE_BUSY)) 722 continue; 723 } 724 if (conflict->flags & flags & IORESOURCE_MUXED) { 725 add_wait_queue(&muxed_resource_wait, &wait); 726 write_unlock(&resource_lock); 727 set_current_state(TASK_UNINTERRUPTIBLE); 728 schedule(); 729 remove_wait_queue(&muxed_resource_wait, &wait); 730 write_lock(&resource_lock); 731 continue; 732 } 733 /* Uhhuh, that didn't work out.. */ 734 kfree(res); 735 res = NULL; 736 break; 737 } 738 write_unlock(&resource_lock); 739 return res; 740} 741EXPORT_SYMBOL(__request_region); 742 743/** 744 * __check_region - check if a resource region is busy or free 745 * @parent: parent resource descriptor 746 * @start: resource start address 747 * @n: resource region size 748 * 749 * Returns 0 if the region is free at the moment it is checked, 750 * returns %-EBUSY if the region is busy. 751 * 752 * NOTE: 753 * This function is deprecated because its use is racy. 754 * Even if it returns 0, a subsequent call to request_region() 755 * may fail because another driver etc. just allocated the region. 756 * Do NOT use it. It will be removed from the kernel. 757 */ 758int __check_region(struct resource *parent, resource_size_t start, 759 resource_size_t n) 760{ 761 struct resource * res; 762 763 res = __request_region(parent, start, n, "check-region", 0); 764 if (!res) 765 return -EBUSY; 766 767 release_resource(res); 768 kfree(res); 769 return 0; 770} 771EXPORT_SYMBOL(__check_region); 772 773/** 774 * __release_region - release a previously reserved resource region 775 * @parent: parent resource descriptor 776 * @start: resource start address 777 * @n: resource region size 778 * 779 * The described resource region must match a currently busy region. 780 */ 781void __release_region(struct resource *parent, resource_size_t start, 782 resource_size_t n) 783{ 784 struct resource **p; 785 resource_size_t end; 786 787 p = &parent->child; 788 end = start + n - 1; 789 790 write_lock(&resource_lock); 791 792 for (;;) { 793 struct resource *res = *p; 794 795 if (!res) 796 break; 797 if (res->start <= start && res->end >= end) { 798 if (!(res->flags & IORESOURCE_BUSY)) { 799 p = &res->child; 800 continue; 801 } 802 if (res->start != start || res->end != end) 803 break; 804 *p = res->sibling; 805 write_unlock(&resource_lock); 806 if (res->flags & IORESOURCE_MUXED) 807 wake_up(&muxed_resource_wait); 808 kfree(res); 809 return; 810 } 811 p = &res->sibling; 812 } 813 814 write_unlock(&resource_lock); 815 816 printk(KERN_WARNING "Trying to free nonexistent resource " 817 "<%016llx-%016llx>\n", (unsigned long long)start, 818 (unsigned long long)end); 819} 820EXPORT_SYMBOL(__release_region); 821 822/* 823 * Managed region resource 824 */ 825struct region_devres { 826 struct resource *parent; 827 resource_size_t start; 828 resource_size_t n; 829}; 830 831static void devm_region_release(struct device *dev, void *res) 832{ 833 struct region_devres *this = res; 834 835 __release_region(this->parent, this->start, this->n); 836} 837 838static int devm_region_match(struct device *dev, void *res, void *match_data) 839{ 840 struct region_devres *this = res, *match = match_data; 841 842 return this->parent == match->parent && 843 this->start == match->start && this->n == match->n; 844} 845 846struct resource * __devm_request_region(struct device *dev, 847 struct resource *parent, resource_size_t start, 848 resource_size_t n, const char *name) 849{ 850 struct region_devres *dr = NULL; 851 struct resource *res; 852 853 dr = devres_alloc(devm_region_release, sizeof(struct region_devres), 854 GFP_KERNEL); 855 if (!dr) 856 return NULL; 857 858 dr->parent = parent; 859 dr->start = start; 860 dr->n = n; 861 862 res = __request_region(parent, start, n, name, 0); 863 if (res) 864 devres_add(dev, dr); 865 else 866 devres_free(dr); 867 868 return res; 869} 870EXPORT_SYMBOL(__devm_request_region); 871 872void __devm_release_region(struct device *dev, struct resource *parent, 873 resource_size_t start, resource_size_t n) 874{ 875 struct region_devres match_data = { parent, start, n }; 876 877 __release_region(parent, start, n); 878 WARN_ON(devres_destroy(dev, devm_region_release, devm_region_match, 879 &match_data)); 880} 881EXPORT_SYMBOL(__devm_release_region); 882 883/* 884 * Called from init/main.c to reserve IO ports. 885 */ 886#define MAXRESERVE 4 887static int __init reserve_setup(char *str) 888{ 889 static int reserved; 890 static struct resource reserve[MAXRESERVE]; 891 892 for (;;) { 893 unsigned int io_start, io_num; 894 int x = reserved; 895 896 if (get_option (&str, &io_start) != 2) 897 break; 898 if (get_option (&str, &io_num) == 0) 899 break; 900 if (x < MAXRESERVE) { 901 struct resource *res = reserve + x; 902 res->name = "reserved"; 903 res->start = io_start; 904 res->end = io_start + io_num - 1; 905 res->flags = IORESOURCE_BUSY; 906 res->child = NULL; 907 if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, res) == 0) 908 reserved = x+1; 909 } 910 } 911 return 1; 912} 913 914__setup("reserve=", reserve_setup); 915 916/* 917 * Check if the requested addr and size spans more than any slot in the 918 * iomem resource tree. 919 */ 920int iomem_map_sanity_check(resource_size_t addr, unsigned long size) 921{ 922 struct resource *p = &iomem_resource; 923 int err = 0; 924 loff_t l; 925 926 read_lock(&resource_lock); 927 for (p = p->child; p ; p = r_next(NULL, p, &l)) { 928 /* 929 * We can probably skip the resources without 930 * IORESOURCE_IO attribute? 931 */ 932 if (p->start >= addr + size) 933 continue; 934 if (p->end < addr) 935 continue; 936 if (PFN_DOWN(p->start) <= PFN_DOWN(addr) && 937 PFN_DOWN(p->end) >= PFN_DOWN(addr + size - 1)) 938 continue; 939 /* 940 * if a resource is "BUSY", it's not a hardware resource 941 * but a driver mapping of such a resource; we don't want 942 * to warn for those; some drivers legitimately map only 943 * partial hardware resources. (example: vesafb) 944 */ 945 if (p->flags & IORESOURCE_BUSY) 946 continue; 947 948 printk(KERN_WARNING "resource map sanity check conflict: " 949 "0x%llx 0x%llx 0x%llx 0x%llx %s\n", 950 (unsigned long long)addr, 951 (unsigned long long)(addr + size - 1), 952 (unsigned long long)p->start, 953 (unsigned long long)p->end, 954 p->name); 955 err = -1; 956 break; 957 } 958 read_unlock(&resource_lock); 959 960 return err; 961} 962 963#ifdef CONFIG_STRICT_DEVMEM 964static int strict_iomem_checks = 1; 965#else 966static int strict_iomem_checks; 967#endif 968 969/* 970 * check if an address is reserved in the iomem resource tree 971 * returns 1 if reserved, 0 if not reserved. 972 */ 973int iomem_is_exclusive(u64 addr) 974{ 975 struct resource *p = &iomem_resource; 976 int err = 0; 977 loff_t l; 978 int size = PAGE_SIZE; 979 980 if (!strict_iomem_checks) 981 return 0; 982 983 addr = addr & PAGE_MASK; 984 985 read_lock(&resource_lock); 986 for (p = p->child; p ; p = r_next(NULL, p, &l)) { 987 /* 988 * We can probably skip the resources without 989 * IORESOURCE_IO attribute? 990 */ 991 if (p->start >= addr + size) 992 break; 993 if (p->end < addr) 994 continue; 995 if (p->flags & IORESOURCE_BUSY && 996 p->flags & IORESOURCE_EXCLUSIVE) { 997 err = 1; 998 break; 999 } 1000 } 1001 read_unlock(&resource_lock); 1002 1003 return err; 1004} 1005 1006static int __init strict_iomem(char *str) 1007{ 1008 if (strstr(str, "relaxed")) 1009 strict_iomem_checks = 0; 1010 if (strstr(str, "strict")) 1011 strict_iomem_checks = 1; 1012 return 1; 1013} 1014 1015__setup("iomem=", strict_iomem); 1016