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authorLinus Torvalds <torvalds@linux-foundation.org>2010-12-18 13:13:24 -0500
committerLinus Torvalds <torvalds@linux-foundation.org>2010-12-18 13:13:24 -0500
commit46bdfe6a50b88942f5323f837a3afd93a1c86e60 (patch)
tree9fe5add84d9bcca4670b1af98940d7267c3a3571 /kernel
parentc15524a40a1603dc56a8691c4f50172fb86c23d8 (diff)
parenta2c606d53ab71dee6410f10ef0adf67321d60e06 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: x86: avoid high BIOS area when allocating address space x86: avoid E820 regions when allocating address space x86: avoid low BIOS area when allocating address space resources: add arch hook for preventing allocation in reserved areas Revert "resources: support allocating space within a region from the top down" Revert "PCI: allocate bus resources from the top down" Revert "x86/PCI: allocate space from the end of a region, not the beginning" Revert "x86: allocate space within a region top-down" Revert "PCI: fix pci_bus_alloc_resource() hang, prefer positive decode" PCI: Update MCP55 quirk to not affect non HyperTransport variants
Diffstat (limited to 'kernel')
-rw-r--r--kernel/resource.c104
1 files changed, 10 insertions, 94 deletions
diff --git a/kernel/resource.c b/kernel/resource.c
index 9fad33efd0db..798e2fae2a06 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -40,23 +40,6 @@ EXPORT_SYMBOL(iomem_resource);
40 40
41static DEFINE_RWLOCK(resource_lock); 41static DEFINE_RWLOCK(resource_lock);
42 42
43/*
44 * By default, we allocate free space bottom-up. The architecture can request
45 * top-down by clearing this flag. The user can override the architecture's
46 * choice with the "resource_alloc_from_bottom" kernel boot option, but that
47 * should only be a debugging tool.
48 */
49int resource_alloc_from_bottom = 1;
50
51static __init int setup_alloc_from_bottom(char *s)
52{
53 printk(KERN_INFO
54 "resource: allocating from bottom-up; please report a bug\n");
55 resource_alloc_from_bottom = 1;
56 return 0;
57}
58early_param("resource_alloc_from_bottom", setup_alloc_from_bottom);
59
60static void *r_next(struct seq_file *m, void *v, loff_t *pos) 43static void *r_next(struct seq_file *m, void *v, loff_t *pos)
61{ 44{
62 struct resource *p = v; 45 struct resource *p = v;
@@ -374,6 +357,10 @@ int __weak page_is_ram(unsigned long pfn)
374 return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1; 357 return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1;
375} 358}
376 359
360void __weak arch_remove_reservations(struct resource *avail)
361{
362}
363
377static resource_size_t simple_align_resource(void *data, 364static resource_size_t simple_align_resource(void *data,
378 const struct resource *avail, 365 const struct resource *avail,
379 resource_size_t size, 366 resource_size_t size,
@@ -397,74 +384,7 @@ static bool resource_contains(struct resource *res1, struct resource *res2)
397} 384}
398 385
399/* 386/*
400 * Find the resource before "child" in the sibling list of "root" children.
401 */
402static struct resource *find_sibling_prev(struct resource *root, struct resource *child)
403{
404 struct resource *this;
405
406 for (this = root->child; this; this = this->sibling)
407 if (this->sibling == child)
408 return this;
409
410 return NULL;
411}
412
413/*
414 * Find empty slot in the resource tree given range and alignment. 387 * Find empty slot in the resource tree given range and alignment.
415 * This version allocates from the end of the root resource first.
416 */
417static int find_resource_from_top(struct resource *root, struct resource *new,
418 resource_size_t size, resource_size_t min,
419 resource_size_t max, resource_size_t align,
420 resource_size_t (*alignf)(void *,
421 const struct resource *,
422 resource_size_t,
423 resource_size_t),
424 void *alignf_data)
425{
426 struct resource *this;
427 struct resource tmp, avail, alloc;
428
429 tmp.start = root->end;
430 tmp.end = root->end;
431
432 this = find_sibling_prev(root, NULL);
433 for (;;) {
434 if (this) {
435 if (this->end < root->end)
436 tmp.start = this->end + 1;
437 } else
438 tmp.start = root->start;
439
440 resource_clip(&tmp, min, max);
441
442 /* Check for overflow after ALIGN() */
443 avail = *new;
444 avail.start = ALIGN(tmp.start, align);
445 avail.end = tmp.end;
446 if (avail.start >= tmp.start) {
447 alloc.start = alignf(alignf_data, &avail, size, align);
448 alloc.end = alloc.start + size - 1;
449 if (resource_contains(&avail, &alloc)) {
450 new->start = alloc.start;
451 new->end = alloc.end;
452 return 0;
453 }
454 }
455
456 if (!this || this->start == root->start)
457 break;
458
459 tmp.end = this->start - 1;
460 this = find_sibling_prev(root, this);
461 }
462 return -EBUSY;
463}
464
465/*
466 * Find empty slot in the resource tree given range and alignment.
467 * This version allocates from the beginning of the root resource first.
468 */ 388 */
469static int find_resource(struct resource *root, struct resource *new, 389static int find_resource(struct resource *root, struct resource *new,
470 resource_size_t size, resource_size_t min, 390 resource_size_t size, resource_size_t min,
@@ -478,23 +398,24 @@ static int find_resource(struct resource *root, struct resource *new,
478 struct resource *this = root->child; 398 struct resource *this = root->child;
479 struct resource tmp = *new, avail, alloc; 399 struct resource tmp = *new, avail, alloc;
480 400
401 tmp.flags = new->flags;
481 tmp.start = root->start; 402 tmp.start = root->start;
482 /* 403 /*
483 * Skip past an allocated resource that starts at 0, since the 404 * Skip past an allocated resource that starts at 0, since the assignment
484 * assignment of this->start - 1 to tmp->end below would cause an 405 * of this->start - 1 to tmp->end below would cause an underflow.
485 * underflow.
486 */ 406 */
487 if (this && this->start == 0) { 407 if (this && this->start == 0) {
488 tmp.start = this->end + 1; 408 tmp.start = this->end + 1;
489 this = this->sibling; 409 this = this->sibling;
490 } 410 }
491 for (;;) { 411 for(;;) {
492 if (this) 412 if (this)
493 tmp.end = this->start - 1; 413 tmp.end = this->start - 1;
494 else 414 else
495 tmp.end = root->end; 415 tmp.end = root->end;
496 416
497 resource_clip(&tmp, min, max); 417 resource_clip(&tmp, min, max);
418 arch_remove_reservations(&tmp);
498 419
499 /* Check for overflow after ALIGN() */ 420 /* Check for overflow after ALIGN() */
500 avail = *new; 421 avail = *new;
@@ -509,10 +430,8 @@ static int find_resource(struct resource *root, struct resource *new,
509 return 0; 430 return 0;
510 } 431 }
511 } 432 }
512
513 if (!this) 433 if (!this)
514 break; 434 break;
515
516 tmp.start = this->end + 1; 435 tmp.start = this->end + 1;
517 this = this->sibling; 436 this = this->sibling;
518 } 437 }
@@ -545,10 +464,7 @@ int allocate_resource(struct resource *root, struct resource *new,
545 alignf = simple_align_resource; 464 alignf = simple_align_resource;
546 465
547 write_lock(&resource_lock); 466 write_lock(&resource_lock);
548 if (resource_alloc_from_bottom) 467 err = find_resource(root, new, size, min, max, align, alignf, alignf_data);
549 err = find_resource(root, new, size, min, max, align, alignf, alignf_data);
550 else
551 err = find_resource_from_top(root, new, size, min, max, align, alignf, alignf_data);
552 if (err >= 0 && __request_resource(root, new)) 468 if (err >= 0 && __request_resource(root, new))
553 err = -EBUSY; 469 err = -EBUSY;
554 write_unlock(&resource_lock); 470 write_unlock(&resource_lock);