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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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11
12#include <linux/export.h>
13#include <linux/errno.h>
14#include <linux/ioport.h>
15#include <linux/init.h>
16#include <linux/slab.h>
17#include <linux/spinlock.h>
18#include <linux/fs.h>
19#include <linux/proc_fs.h>
20#include <linux/sched.h>
21#include <linux/seq_file.h>
22#include <linux/device.h>
23#include <linux/pfn.h>
24#include <linux/mm.h>
25#include <asm/io.h>
26
27
28struct resource ioport_resource = {
29 .name = "PCI IO",
30 .start = 0,
31 .end = IO_SPACE_LIMIT,
32 .flags = IORESOURCE_IO,
33};
34EXPORT_SYMBOL(ioport_resource);
35
36struct resource iomem_resource = {
37 .name = "PCI mem",
38 .start = 0,
39 .end = -1,
40 .flags = IORESOURCE_MEM,
41};
42EXPORT_SYMBOL(iomem_resource);
43
44/* constraints to be met while allocating resources */
45struct resource_constraint {
46 resource_size_t min, max, align;
47 resource_size_t (*alignf)(void *, const struct resource *,
48 resource_size_t, resource_size_t);
49 void *alignf_data;
50};
51
52static DEFINE_RWLOCK(resource_lock);
53
54/*
55 * For memory hotplug, there is no way to free resource entries allocated
56 * by boot mem after the system is up. So for reusing the resource entry
57 * we need to remember the resource.
58 */
59static struct resource *bootmem_resource_free;
60static DEFINE_SPINLOCK(bootmem_resource_lock);
61
62static void *r_next(struct seq_file *m, void *v, loff_t *pos)
63{
64 struct resource *p = v;
65 (*pos)++;
66 if (p->child)
67 return p->child;
68 while (!p->sibling && p->parent)
69 p = p->parent;
70 return p->sibling;
71}
72
73#ifdef CONFIG_PROC_FS
74
75enum { MAX_IORES_LEVEL = 5 };
76
77static void *r_start(struct seq_file *m, loff_t *pos)
78 __acquires(resource_lock)
79{
80 struct resource *p = m->private;
81 loff_t l = 0;
82 read_lock(&resource_lock);
83 for (p = p->child; p && l < *pos; p = r_next(m, p, &l))
84 ;
85 return p;
86}
87
88static void r_stop(struct seq_file *m, void *v)
89 __releases(resource_lock)
90{
91 read_unlock(&resource_lock);
92}
93
94static int r_show(struct seq_file *m, void *v)
95{
96 struct resource *root = m->private;
97 struct resource *r = v, *p;
98 int width = root->end < 0x10000 ? 4 : 8;
99 int depth;
100
101 for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent)
102 if (p->parent == root)
103 break;
104 seq_printf(m, "%*s%0*llx-%0*llx : %s\n",
105 depth * 2, "",
106 width, (unsigned long long) r->start,
107 width, (unsigned long long) r->end,
108 r->name ? r->name : "<BAD>");
109 return 0;
110}
111
112static const struct seq_operations resource_op = {
113 .start = r_start,
114 .next = r_next,
115 .stop = r_stop,
116 .show = r_show,
117};
118
119static int ioports_open(struct inode *inode, struct file *file)
120{
121 int res = seq_open(file, &resource_op);
122 if (!res) {
123 struct seq_file *m = file->private_data;
124 m->private = &ioport_resource;
125 }
126 return res;
127}
128
129static int iomem_open(struct inode *inode, struct file *file)
130{
131 int res = seq_open(file, &resource_op);
132 if (!res) {
133 struct seq_file *m = file->private_data;
134 m->private = &iomem_resource;
135 }
136 return res;
137}
138
139static const struct file_operations proc_ioports_operations = {
140 .open = ioports_open,
141 .read = seq_read,
142 .llseek = seq_lseek,
143 .release = seq_release,
144};
145
146static const struct file_operations proc_iomem_operations = {
147 .open = iomem_open,
148 .read = seq_read,
149 .llseek = seq_lseek,
150 .release = seq_release,
151};
152
153static int __init ioresources_init(void)
154{
155 proc_create("ioports", 0, NULL, &proc_ioports_operations);
156 proc_create("iomem", 0, NULL, &proc_iomem_operations);
157 return 0;
158}
159__initcall(ioresources_init);
160
161#endif /* CONFIG_PROC_FS */
162
163static void free_resource(struct resource *res)
164{
165 if (!res)
166 return;
167
168 if (!PageSlab(virt_to_head_page(res))) {
169 spin_lock(&bootmem_resource_lock);
170 res->sibling = bootmem_resource_free;
171 bootmem_resource_free = res;
172 spin_unlock(&bootmem_resource_lock);
173 } else {
174 kfree(res);
175 }
176}
177
178static struct resource *alloc_resource(gfp_t flags)
179{
180 struct resource *res = NULL;
181
182 spin_lock(&bootmem_resource_lock);
183 if (bootmem_resource_free) {
184 res = bootmem_resource_free;
185 bootmem_resource_free = res->sibling;
186 }
187 spin_unlock(&bootmem_resource_lock);
188
189 if (res)
190 memset(res, 0, sizeof(struct resource));
191 else
192 res = kzalloc(sizeof(struct resource), flags);
193
194 return res;
195}
196
197/* Return the conflict entry if you can't request it */
198static struct resource * __request_resource(struct resource *root, struct resource *new)
199{
200 resource_size_t start = new->start;
201 resource_size_t end = new->end;
202 struct resource *tmp, **p;
203
204 if (end < start)
205 return root;
206 if (start < root->start)
207 return root;
208 if (end > root->end)
209 return root;
210 p = &root->child;
211 for (;;) {
212 tmp = *p;
213 if (!tmp || tmp->start > end) {
214 new->sibling = tmp;
215 *p = new;
216 new->parent = root;
217 return NULL;
218 }
219 p = &tmp->sibling;
220 if (tmp->end < start)
221 continue;
222 return tmp;
223 }
224}
225
226static int __release_resource(struct resource *old)
227{
228 struct resource *tmp, **p;
229
230 p = &old->parent->child;
231 for (;;) {
232 tmp = *p;
233 if (!tmp)
234 break;
235 if (tmp == old) {
236 *p = tmp->sibling;
237 old->parent = NULL;
238 return 0;
239 }
240 p = &tmp->sibling;
241 }
242 return -EINVAL;
243}
244
245static void __release_child_resources(struct resource *r)
246{
247 struct resource *tmp, *p;
248 resource_size_t size;
249
250 p = r->child;
251 r->child = NULL;
252 while (p) {
253 tmp = p;
254 p = p->sibling;
255
256 tmp->parent = NULL;
257 tmp->sibling = NULL;
258 __release_child_resources(tmp);
259
260 printk(KERN_DEBUG "release child resource %pR\n", tmp);
261 /* need to restore size, and keep flags */
262 size = resource_size(tmp);
263 tmp->start = 0;
264 tmp->end = size - 1;
265 }
266}
267
268void release_child_resources(struct resource *r)
269{
270 write_lock(&resource_lock);
271 __release_child_resources(r);
272 write_unlock(&resource_lock);
273}
274
275/**
276 * request_resource_conflict - request and reserve an I/O or memory resource
277 * @root: root resource descriptor
278 * @new: resource descriptor desired by caller
279 *
280 * Returns 0 for success, conflict resource on error.
281 */
282struct resource *request_resource_conflict(struct resource *root, struct resource *new)
283{
284 struct resource *conflict;
285
286 write_lock(&resource_lock);
287 conflict = __request_resource(root, new);
288 write_unlock(&resource_lock);
289 return conflict;
290}
291
292/**
293 * request_resource - request and reserve an I/O or memory resource
294 * @root: root resource descriptor
295 * @new: resource descriptor desired by caller
296 *
297 * Returns 0 for success, negative error code on error.
298 */
299int request_resource(struct resource *root, struct resource *new)
300{
301 struct resource *conflict;
302
303 conflict = request_resource_conflict(root, new);
304 return conflict ? -EBUSY : 0;
305}
306
307EXPORT_SYMBOL(request_resource);
308
309/**
310 * release_resource - release a previously reserved resource
311 * @old: resource pointer
312 */
313int release_resource(struct resource *old)
314{
315 int retval;
316
317 write_lock(&resource_lock);
318 retval = __release_resource(old);
319 write_unlock(&resource_lock);
320 return retval;
321}
322
323EXPORT_SYMBOL(release_resource);
324
325#if !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
326/*
327 * Finds the lowest memory reosurce exists within [res->start.res->end)
328 * the caller must specify res->start, res->end, res->flags and "name".
329 * If found, returns 0, res is overwritten, if not found, returns -1.
330 */
331static int find_next_system_ram(struct resource *res, char *name)
332{
333 resource_size_t start, end;
334 struct resource *p;
335
336 BUG_ON(!res);
337
338 start = res->start;
339 end = res->end;
340 BUG_ON(start >= end);
341
342 read_lock(&resource_lock);
343 for (p = iomem_resource.child; p ; p = p->sibling) {
344 /* system ram is just marked as IORESOURCE_MEM */
345 if (p->flags != res->flags)
346 continue;
347 if (name && strcmp(p->name, name))
348 continue;
349 if (p->start > end) {
350 p = NULL;
351 break;
352 }
353 if ((p->end >= start) && (p->start < end))
354 break;
355 }
356 read_unlock(&resource_lock);
357 if (!p)
358 return -1;
359 /* copy data */
360 if (res->start < p->start)
361 res->start = p->start;
362 if (res->end > p->end)
363 res->end = p->end;
364 return 0;
365}
366
367/*
368 * This function calls callback against all memory range of "System RAM"
369 * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY.
370 * Now, this function is only for "System RAM".
371 */
372int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
373 void *arg, int (*func)(unsigned long, unsigned long, void *))
374{
375 struct resource res;
376 unsigned long pfn, end_pfn;
377 u64 orig_end;
378 int ret = -1;
379
380 res.start = (u64) start_pfn << PAGE_SHIFT;
381 res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1;
382 res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
383 orig_end = res.end;
384 while ((res.start < res.end) &&
385 (find_next_system_ram(&res, "System RAM") >= 0)) {
386 pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT;
387 end_pfn = (res.end + 1) >> PAGE_SHIFT;
388 if (end_pfn > pfn)
389 ret = (*func)(pfn, end_pfn - pfn, arg);
390 if (ret)
391 break;
392 res.start = res.end + 1;
393 res.end = orig_end;
394 }
395 return ret;
396}
397
398#endif
399
400static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg)
401{
402 return 1;
403}
404/*
405 * This generic page_is_ram() returns true if specified address is
406 * registered as "System RAM" in iomem_resource list.
407 */
408int __weak page_is_ram(unsigned long pfn)
409{
410 return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1;
411}
412EXPORT_SYMBOL_GPL(page_is_ram);
413
414void __weak arch_remove_reservations(struct resource *avail)
415{
416}
417
418static resource_size_t simple_align_resource(void *data,
419 const struct resource *avail,
420 resource_size_t size,
421 resource_size_t align)
422{
423 return avail->start;
424}
425
426static void resource_clip(struct resource *res, resource_size_t min,
427 resource_size_t max)
428{
429 if (res->start < min)
430 res->start = min;
431 if (res->end > max)
432 res->end = max;
433}
434
435/*
436 * Find empty slot in the resource tree with the given range and
437 * alignment constraints
438 */
439static int __find_resource(struct resource *root, struct resource *old,
440 struct resource *new,
441 resource_size_t size,
442 struct resource_constraint *constraint)
443{
444 struct resource *this = root->child;
445 struct resource tmp = *new, avail, alloc;
446
447 tmp.start = root->start;
448 /*
449 * Skip past an allocated resource that starts at 0, since the assignment
450 * of this->start - 1 to tmp->end below would cause an underflow.
451 */
452 if (this && this->start == root->start) {
453 tmp.start = (this == old) ? old->start : this->end + 1;
454 this = this->sibling;
455 }
456 for(;;) {
457 if (this)
458 tmp.end = (this == old) ? this->end : this->start - 1;
459 else
460 tmp.end = root->end;
461
462 if (tmp.end < tmp.start)
463 goto next;
464
465 resource_clip(&tmp, constraint->min, constraint->max);
466 arch_remove_reservations(&tmp);
467
468 /* Check for overflow after ALIGN() */
469 avail.start = ALIGN(tmp.start, constraint->align);
470 avail.end = tmp.end;
471 avail.flags = new->flags & ~IORESOURCE_UNSET;
472 if (avail.start >= tmp.start) {
473 alloc.flags = avail.flags;
474 alloc.start = constraint->alignf(constraint->alignf_data, &avail,
475 size, constraint->align);
476 alloc.end = alloc.start + size - 1;
477 if (resource_contains(&avail, &alloc)) {
478 new->start = alloc.start;
479 new->end = alloc.end;
480 return 0;
481 }
482 }
483
484next: if (!this || this->end == root->end)
485 break;
486
487 if (this != old)
488 tmp.start = this->end + 1;
489 this = this->sibling;
490 }
491 return -EBUSY;
492}
493
494/*
495 * Find empty slot in the resource tree given range and alignment.
496 */
497static int find_resource(struct resource *root, struct resource *new,
498 resource_size_t size,
499 struct resource_constraint *constraint)
500{
501 return __find_resource(root, NULL, new, size, constraint);
502}
503
504/**
505 * reallocate_resource - allocate a slot in the resource tree given range & alignment.
506 * The resource will be relocated if the new size cannot be reallocated in the
507 * current location.
508 *
509 * @root: root resource descriptor
510 * @old: resource descriptor desired by caller
511 * @newsize: new size of the resource descriptor
512 * @constraint: the size and alignment constraints to be met.
513 */
514static int reallocate_resource(struct resource *root, struct resource *old,
515 resource_size_t newsize,
516 struct resource_constraint *constraint)
517{
518 int err=0;
519 struct resource new = *old;
520 struct resource *conflict;
521
522 write_lock(&resource_lock);
523
524 if ((err = __find_resource(root, old, &new, newsize, constraint)))
525 goto out;
526
527 if (resource_contains(&new, old)) {
528 old->start = new.start;
529 old->end = new.end;
530 goto out;
531 }
532
533 if (old->child) {
534 err = -EBUSY;
535 goto out;
536 }
537
538 if (resource_contains(old, &new)) {
539 old->start = new.start;
540 old->end = new.end;
541 } else {
542 __release_resource(old);
543 *old = new;
544 conflict = __request_resource(root, old);
545 BUG_ON(conflict);
546 }
547out:
548 write_unlock(&resource_lock);
549 return err;
550}
551
552
553/**
554 * allocate_resource - allocate empty slot in the resource tree given range & alignment.
555 * The resource will be reallocated with a new size if it was already allocated
556 * @root: root resource descriptor
557 * @new: resource descriptor desired by caller
558 * @size: requested resource region size
559 * @min: minimum boundary to allocate
560 * @max: maximum boundary to allocate
561 * @align: alignment requested, in bytes
562 * @alignf: alignment function, optional, called if not NULL
563 * @alignf_data: arbitrary data to pass to the @alignf function
564 */
565int allocate_resource(struct resource *root, struct resource *new,
566 resource_size_t size, resource_size_t min,
567 resource_size_t max, resource_size_t align,
568 resource_size_t (*alignf)(void *,
569 const struct resource *,
570 resource_size_t,
571 resource_size_t),
572 void *alignf_data)
573{
574 int err;
575 struct resource_constraint constraint;
576
577 if (!alignf)
578 alignf = simple_align_resource;
579
580 constraint.min = min;
581 constraint.max = max;
582 constraint.align = align;
583 constraint.alignf = alignf;
584 constraint.alignf_data = alignf_data;
585
586 if ( new->parent ) {
587 /* resource is already allocated, try reallocating with
588 the new constraints */
589 return reallocate_resource(root, new, size, &constraint);
590 }
591
592 write_lock(&resource_lock);
593 err = find_resource(root, new, size, &constraint);
594 if (err >= 0 && __request_resource(root, new))
595 err = -EBUSY;
596 write_unlock(&resource_lock);
597 return err;
598}
599
600EXPORT_SYMBOL(allocate_resource);
601
602/**
603 * lookup_resource - find an existing resource by a resource start address
604 * @root: root resource descriptor
605 * @start: resource start address
606 *
607 * Returns a pointer to the resource if found, NULL otherwise
608 */
609struct resource *lookup_resource(struct resource *root, resource_size_t start)
610{
611 struct resource *res;
612
613 read_lock(&resource_lock);
614 for (res = root->child; res; res = res->sibling) {
615 if (res->start == start)
616 break;
617 }
618 read_unlock(&resource_lock);
619
620 return res;
621}
622
623/*
624 * Insert a resource into the resource tree. If successful, return NULL,
625 * otherwise return the conflicting resource (compare to __request_resource())
626 */
627static struct resource * __insert_resource(struct resource *parent, struct resource *new)
628{
629 struct resource *first, *next;
630
631 for (;; parent = first) {
632 first = __request_resource(parent, new);
633 if (!first)
634 return first;
635
636 if (first == parent)
637 return first;
638 if (WARN_ON(first == new)) /* duplicated insertion */
639 return first;
640
641 if ((first->start > new->start) || (first->end < new->end))
642 break;
643 if ((first->start == new->start) && (first->end == new->end))
644 break;
645 }
646
647 for (next = first; ; next = next->sibling) {
648 /* Partial overlap? Bad, and unfixable */
649 if (next->start < new->start || next->end > new->end)
650 return next;
651 if (!next->sibling)
652 break;
653 if (next->sibling->start > new->end)
654 break;
655 }
656
657 new->parent = parent;
658 new->sibling = next->sibling;
659 new->child = first;
660
661 next->sibling = NULL;
662 for (next = first; next; next = next->sibling)
663 next->parent = new;
664
665 if (parent->child == first) {
666 parent->child = new;
667 } else {
668 next = parent->child;
669 while (next->sibling != first)
670 next = next->sibling;
671 next->sibling = new;
672 }
673 return NULL;
674}
675
676/**
677 * insert_resource_conflict - Inserts resource in the resource tree
678 * @parent: parent of the new resource
679 * @new: new resource to insert
680 *
681 * Returns 0 on success, conflict resource if the resource can't be inserted.
682 *
683 * This function is equivalent to request_resource_conflict when no conflict
684 * happens. If a conflict happens, and the conflicting resources
685 * entirely fit within the range of the new resource, then the new
686 * resource is inserted and the conflicting resources become children of
687 * the new resource.
688 */
689struct resource *insert_resource_conflict(struct resource *parent, struct resource *new)
690{
691 struct resource *conflict;
692
693 write_lock(&resource_lock);
694 conflict = __insert_resource(parent, new);
695 write_unlock(&resource_lock);
696 return conflict;
697}
698
699/**
700 * insert_resource - Inserts a resource in the resource tree
701 * @parent: parent of the new resource
702 * @new: new resource to insert
703 *
704 * Returns 0 on success, -EBUSY if the resource can't be inserted.
705 */
706int insert_resource(struct resource *parent, struct resource *new)
707{
708 struct resource *conflict;
709
710 conflict = insert_resource_conflict(parent, new);
711 return conflict ? -EBUSY : 0;
712}
713
714/**
715 * insert_resource_expand_to_fit - Insert a resource into the resource tree
716 * @root: root resource descriptor
717 * @new: new resource to insert
718 *
719 * Insert a resource into the resource tree, possibly expanding it in order
720 * to make it encompass any conflicting resources.
721 */
722void insert_resource_expand_to_fit(struct resource *root, struct resource *new)
723{
724 if (new->parent)
725 return;
726
727 write_lock(&resource_lock);
728 for (;;) {
729 struct resource *conflict;
730
731 conflict = __insert_resource(root, new);
732 if (!conflict)
733 break;
734 if (conflict == root)
735 break;
736
737 /* Ok, expand resource to cover the conflict, then try again .. */
738 if (conflict->start < new->start)
739 new->start = conflict->start;
740 if (conflict->end > new->end)
741 new->end = conflict->end;
742
743 printk("Expanded resource %s due to conflict with %s\n", new->name, conflict->name);
744 }
745 write_unlock(&resource_lock);
746}
747
748static int __adjust_resource(struct resource *res, resource_size_t start,
749 resource_size_t size)
750{
751 struct resource *tmp, *parent = res->parent;
752 resource_size_t end = start + size - 1;
753 int result = -EBUSY;
754
755 if (!parent)
756 goto skip;
757
758 if ((start < parent->start) || (end > parent->end))
759 goto out;
760
761 if (res->sibling && (res->sibling->start <= end))
762 goto out;
763
764 tmp = parent->child;
765 if (tmp != res) {
766 while (tmp->sibling != res)
767 tmp = tmp->sibling;
768 if (start <= tmp->end)
769 goto out;
770 }
771
772skip:
773 for (tmp = res->child; tmp; tmp = tmp->sibling)
774 if ((tmp->start < start) || (tmp->end > end))
775 goto out;
776
777 res->start = start;
778 res->end = end;
779 result = 0;
780
781 out:
782 return result;
783}
784
785/**
786 * adjust_resource - modify a resource's start and size
787 * @res: resource to modify
788 * @start: new start value
789 * @size: new size
790 *
791 * Given an existing resource, change its start and size to match the
792 * arguments. Returns 0 on success, -EBUSY if it can't fit.
793 * Existing children of the resource are assumed to be immutable.
794 */
795int adjust_resource(struct resource *res, resource_size_t start,
796 resource_size_t size)
797{
798 int result;
799
800 write_lock(&resource_lock);
801 result = __adjust_resource(res, start, size);
802 write_unlock(&resource_lock);
803 return result;
804}
805EXPORT_SYMBOL(adjust_resource);
806
807static void __init __reserve_region_with_split(struct resource *root,
808 resource_size_t start, resource_size_t end,
809 const char *name)
810{
811 struct resource *parent = root;
812 struct resource *conflict;
813 struct resource *res = alloc_resource(GFP_ATOMIC);
814 struct resource *next_res = NULL;
815
816 if (!res)
817 return;
818
819 res->name = name;
820 res->start = start;
821 res->end = end;
822 res->flags = IORESOURCE_BUSY;
823
824 while (1) {
825
826 conflict = __request_resource(parent, res);
827 if (!conflict) {
828 if (!next_res)
829 break;
830 res = next_res;
831 next_res = NULL;
832 continue;
833 }
834
835 /* conflict covered whole area */
836 if (conflict->start <= res->start &&
837 conflict->end >= res->end) {
838 free_resource(res);
839 WARN_ON(next_res);
840 break;
841 }
842
843 /* failed, split and try again */
844 if (conflict->start > res->start) {
845 end = res->end;
846 res->end = conflict->start - 1;
847 if (conflict->end < end) {
848 next_res = alloc_resource(GFP_ATOMIC);
849 if (!next_res) {
850 free_resource(res);
851 break;
852 }
853 next_res->name = name;
854 next_res->start = conflict->end + 1;
855 next_res->end = end;
856 next_res->flags = IORESOURCE_BUSY;
857 }
858 } else {
859 res->start = conflict->end + 1;
860 }
861 }
862
863}
864
865void __init reserve_region_with_split(struct resource *root,
866 resource_size_t start, resource_size_t end,
867 const char *name)
868{
869 int abort = 0;
870
871 write_lock(&resource_lock);
872 if (root->start > start || root->end < end) {
873 pr_err("requested range [0x%llx-0x%llx] not in root %pr\n",
874 (unsigned long long)start, (unsigned long long)end,
875 root);
876 if (start > root->end || end < root->start)
877 abort = 1;
878 else {
879 if (end > root->end)
880 end = root->end;
881 if (start < root->start)
882 start = root->start;
883 pr_err("fixing request to [0x%llx-0x%llx]\n",
884 (unsigned long long)start,
885 (unsigned long long)end);
886 }
887 dump_stack();
888 }
889 if (!abort)
890 __reserve_region_with_split(root, start, end, name);
891 write_unlock(&resource_lock);
892}
893
894/**
895 * resource_alignment - calculate resource's alignment
896 * @res: resource pointer
897 *
898 * Returns alignment on success, 0 (invalid alignment) on failure.
899 */
900resource_size_t resource_alignment(struct resource *res)
901{
902 switch (res->flags & (IORESOURCE_SIZEALIGN | IORESOURCE_STARTALIGN)) {
903 case IORESOURCE_SIZEALIGN:
904 return resource_size(res);
905 case IORESOURCE_STARTALIGN:
906 return res->start;
907 default:
908 return 0;
909 }
910}
911
912/*
913 * This is compatibility stuff for IO resources.
914 *
915 * Note how this, unlike the above, knows about
916 * the IO flag meanings (busy etc).
917 *
918 * request_region creates a new busy region.
919 *
920 * check_region returns non-zero if the area is already busy.
921 *
922 * release_region releases a matching busy region.
923 */
924
925static DECLARE_WAIT_QUEUE_HEAD(muxed_resource_wait);
926
927/**
928 * __request_region - create a new busy resource region
929 * @parent: parent resource descriptor
930 * @start: resource start address
931 * @n: resource region size
932 * @name: reserving caller's ID string
933 * @flags: IO resource flags
934 */
935struct resource * __request_region(struct resource *parent,
936 resource_size_t start, resource_size_t n,
937 const char *name, int flags)
938{
939 DECLARE_WAITQUEUE(wait, current);
940 struct resource *res = alloc_resource(GFP_KERNEL);
941
942 if (!res)
943 return NULL;
944
945 res->name = name;
946 res->start = start;
947 res->end = start + n - 1;
948 res->flags = resource_type(parent);
949 res->flags |= IORESOURCE_BUSY | flags;
950
951 write_lock(&resource_lock);
952
953 for (;;) {
954 struct resource *conflict;
955
956 conflict = __request_resource(parent, res);
957 if (!conflict)
958 break;
959 if (conflict != parent) {
960 parent = conflict;
961 if (!(conflict->flags & IORESOURCE_BUSY))
962 continue;
963 }
964 if (conflict->flags & flags & IORESOURCE_MUXED) {
965 add_wait_queue(&muxed_resource_wait, &wait);
966 write_unlock(&resource_lock);
967 set_current_state(TASK_UNINTERRUPTIBLE);
968 schedule();
969 remove_wait_queue(&muxed_resource_wait, &wait);
970 write_lock(&resource_lock);
971 continue;
972 }
973 /* Uhhuh, that didn't work out.. */
974 free_resource(res);
975 res = NULL;
976 break;
977 }
978 write_unlock(&resource_lock);
979 return res;
980}
981EXPORT_SYMBOL(__request_region);
982
983/**
984 * __check_region - check if a resource region is busy or free
985 * @parent: parent resource descriptor
986 * @start: resource start address
987 * @n: resource region size
988 *
989 * Returns 0 if the region is free at the moment it is checked,
990 * returns %-EBUSY if the region is busy.
991 *
992 * NOTE:
993 * This function is deprecated because its use is racy.
994 * Even if it returns 0, a subsequent call to request_region()
995 * may fail because another driver etc. just allocated the region.
996 * Do NOT use it. It will be removed from the kernel.
997 */
998int __check_region(struct resource *parent, resource_size_t start,
999 resource_size_t n)
1000{
1001 struct resource * res;
1002
1003 res = __request_region(parent, start, n, "check-region", 0);
1004 if (!res)
1005 return -EBUSY;
1006
1007 release_resource(res);
1008 free_resource(res);
1009 return 0;
1010}
1011EXPORT_SYMBOL(__check_region);
1012
1013/**
1014 * __release_region - release a previously reserved resource region
1015 * @parent: parent resource descriptor
1016 * @start: resource start address
1017 * @n: resource region size
1018 *
1019 * The described resource region must match a currently busy region.
1020 */
1021void __release_region(struct resource *parent, resource_size_t start,
1022 resource_size_t n)
1023{
1024 struct resource **p;
1025 resource_size_t end;
1026
1027 p = &parent->child;
1028 end = start + n - 1;
1029
1030 write_lock(&resource_lock);
1031
1032 for (;;) {
1033 struct resource *res = *p;
1034
1035 if (!res)
1036 break;
1037 if (res->start <= start && res->end >= end) {
1038 if (!(res->flags & IORESOURCE_BUSY)) {
1039 p = &res->child;
1040 continue;
1041 }
1042 if (res->start != start || res->end != end)
1043 break;
1044 *p = res->sibling;
1045 write_unlock(&resource_lock);
1046 if (res->flags & IORESOURCE_MUXED)
1047 wake_up(&muxed_resource_wait);
1048 free_resource(res);
1049 return;
1050 }
1051 p = &res->sibling;
1052 }
1053
1054 write_unlock(&resource_lock);
1055
1056 printk(KERN_WARNING "Trying to free nonexistent resource "
1057 "<%016llx-%016llx>\n", (unsigned long long)start,
1058 (unsigned long long)end);
1059}
1060EXPORT_SYMBOL(__release_region);
1061
1062#ifdef CONFIG_MEMORY_HOTREMOVE
1063/**
1064 * release_mem_region_adjustable - release a previously reserved memory region
1065 * @parent: parent resource descriptor
1066 * @start: resource start address
1067 * @size: resource region size
1068 *
1069 * This interface is intended for memory hot-delete. The requested region
1070 * is released from a currently busy memory resource. The requested region
1071 * must either match exactly or fit into a single busy resource entry. In
1072 * the latter case, the remaining resource is adjusted accordingly.
1073 * Existing children of the busy memory resource must be immutable in the
1074 * request.
1075 *
1076 * Note:
1077 * - Additional release conditions, such as overlapping region, can be
1078 * supported after they are confirmed as valid cases.
1079 * - When a busy memory resource gets split into two entries, the code
1080 * assumes that all children remain in the lower address entry for
1081 * simplicity. Enhance this logic when necessary.
1082 */
1083int release_mem_region_adjustable(struct resource *parent,
1084 resource_size_t start, resource_size_t size)
1085{
1086 struct resource **p;
1087 struct resource *res;
1088 struct resource *new_res;
1089 resource_size_t end;
1090 int ret = -EINVAL;
1091
1092 end = start + size - 1;
1093 if ((start < parent->start) || (end > parent->end))
1094 return ret;
1095
1096 /* The alloc_resource() result gets checked later */
1097 new_res = alloc_resource(GFP_KERNEL);
1098
1099 p = &parent->child;
1100 write_lock(&resource_lock);
1101
1102 while ((res = *p)) {
1103 if (res->start >= end)
1104 break;
1105
1106 /* look for the next resource if it does not fit into */
1107 if (res->start > start || res->end < end) {
1108 p = &res->sibling;
1109 continue;
1110 }
1111
1112 if (!(res->flags & IORESOURCE_MEM))
1113 break;
1114
1115 if (!(res->flags & IORESOURCE_BUSY)) {
1116 p = &res->child;
1117 continue;
1118 }
1119
1120 /* found the target resource; let's adjust accordingly */
1121 if (res->start == start && res->end == end) {
1122 /* free the whole entry */
1123 *p = res->sibling;
1124 free_resource(res);
1125 ret = 0;
1126 } else if (res->start == start && res->end != end) {
1127 /* adjust the start */
1128 ret = __adjust_resource(res, end + 1,
1129 res->end - end);
1130 } else if (res->start != start && res->end == end) {
1131 /* adjust the end */
1132 ret = __adjust_resource(res, res->start,
1133 start - res->start);
1134 } else {
1135 /* split into two entries */
1136 if (!new_res) {
1137 ret = -ENOMEM;
1138 break;
1139 }
1140 new_res->name = res->name;
1141 new_res->start = end + 1;
1142 new_res->end = res->end;
1143 new_res->flags = res->flags;
1144 new_res->parent = res->parent;
1145 new_res->sibling = res->sibling;
1146 new_res->child = NULL;
1147
1148 ret = __adjust_resource(res, res->start,
1149 start - res->start);
1150 if (ret)
1151 break;
1152 res->sibling = new_res;
1153 new_res = NULL;
1154 }
1155
1156 break;
1157 }
1158
1159 write_unlock(&resource_lock);
1160 free_resource(new_res);
1161 return ret;
1162}
1163#endif /* CONFIG_MEMORY_HOTREMOVE */
1164
1165/*
1166 * Managed region resource
1167 */
1168struct region_devres {
1169 struct resource *parent;
1170 resource_size_t start;
1171 resource_size_t n;
1172};
1173
1174static void devm_region_release(struct device *dev, void *res)
1175{
1176 struct region_devres *this = res;
1177
1178 __release_region(this->parent, this->start, this->n);
1179}
1180
1181static int devm_region_match(struct device *dev, void *res, void *match_data)
1182{
1183 struct region_devres *this = res, *match = match_data;
1184
1185 return this->parent == match->parent &&
1186 this->start == match->start && this->n == match->n;
1187}
1188
1189struct resource * __devm_request_region(struct device *dev,
1190 struct resource *parent, resource_size_t start,
1191 resource_size_t n, const char *name)
1192{
1193 struct region_devres *dr = NULL;
1194 struct resource *res;
1195
1196 dr = devres_alloc(devm_region_release, sizeof(struct region_devres),
1197 GFP_KERNEL);
1198 if (!dr)
1199 return NULL;
1200
1201 dr->parent = parent;
1202 dr->start = start;
1203 dr->n = n;
1204
1205 res = __request_region(parent, start, n, name, 0);
1206 if (res)
1207 devres_add(dev, dr);
1208 else
1209 devres_free(dr);
1210
1211 return res;
1212}
1213EXPORT_SYMBOL(__devm_request_region);
1214
1215void __devm_release_region(struct device *dev, struct resource *parent,
1216 resource_size_t start, resource_size_t n)
1217{
1218 struct region_devres match_data = { parent, start, n };
1219
1220 __release_region(parent, start, n);
1221 WARN_ON(devres_destroy(dev, devm_region_release, devm_region_match,
1222 &match_data));
1223}
1224EXPORT_SYMBOL(__devm_release_region);
1225
1226/*
1227 * Called from init/main.c to reserve IO ports.
1228 */
1229#define MAXRESERVE 4
1230static int __init reserve_setup(char *str)
1231{
1232 static int reserved;
1233 static struct resource reserve[MAXRESERVE];
1234
1235 for (;;) {
1236 unsigned int io_start, io_num;
1237 int x = reserved;
1238
1239 if (get_option (&str, &io_start) != 2)
1240 break;
1241 if (get_option (&str, &io_num) == 0)
1242 break;
1243 if (x < MAXRESERVE) {
1244 struct resource *res = reserve + x;
1245 res->name = "reserved";
1246 res->start = io_start;
1247 res->end = io_start + io_num - 1;
1248 res->flags = IORESOURCE_BUSY;
1249 res->child = NULL;
1250 if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, res) == 0)
1251 reserved = x+1;
1252 }
1253 }
1254 return 1;
1255}
1256
1257__setup("reserve=", reserve_setup);
1258
1259/*
1260 * Check if the requested addr and size spans more than any slot in the
1261 * iomem resource tree.
1262 */
1263int iomem_map_sanity_check(resource_size_t addr, unsigned long size)
1264{
1265 struct resource *p = &iomem_resource;
1266 int err = 0;
1267 loff_t l;
1268
1269 read_lock(&resource_lock);
1270 for (p = p->child; p ; p = r_next(NULL, p, &l)) {
1271 /*
1272 * We can probably skip the resources without
1273 * IORESOURCE_IO attribute?
1274 */
1275 if (p->start >= addr + size)
1276 continue;
1277 if (p->end < addr)
1278 continue;
1279 if (PFN_DOWN(p->start) <= PFN_DOWN(addr) &&
1280 PFN_DOWN(p->end) >= PFN_DOWN(addr + size - 1))
1281 continue;
1282 /*
1283 * if a resource is "BUSY", it's not a hardware resource
1284 * but a driver mapping of such a resource; we don't want
1285 * to warn for those; some drivers legitimately map only
1286 * partial hardware resources. (example: vesafb)
1287 */
1288 if (p->flags & IORESOURCE_BUSY)
1289 continue;
1290
1291 printk(KERN_WARNING "resource map sanity check conflict: "
1292 "0x%llx 0x%llx 0x%llx 0x%llx %s\n",
1293 (unsigned long long)addr,
1294 (unsigned long long)(addr + size - 1),
1295 (unsigned long long)p->start,
1296 (unsigned long long)p->end,
1297 p->name);
1298 err = -1;
1299 break;
1300 }
1301 read_unlock(&resource_lock);
1302
1303 return err;
1304}
1305
1306#ifdef CONFIG_STRICT_DEVMEM
1307static int strict_iomem_checks = 1;
1308#else
1309static int strict_iomem_checks;
1310#endif
1311
1312/*
1313 * check if an address is reserved in the iomem resource tree
1314 * returns 1 if reserved, 0 if not reserved.
1315 */
1316int iomem_is_exclusive(u64 addr)
1317{
1318 struct resource *p = &iomem_resource;
1319 int err = 0;
1320 loff_t l;
1321 int size = PAGE_SIZE;
1322
1323 if (!strict_iomem_checks)
1324 return 0;
1325
1326 addr = addr & PAGE_MASK;
1327
1328 read_lock(&resource_lock);
1329 for (p = p->child; p ; p = r_next(NULL, p, &l)) {
1330 /*
1331 * We can probably skip the resources without
1332 * IORESOURCE_IO attribute?
1333 */
1334 if (p->start >= addr + size)
1335 break;
1336 if (p->end < addr)
1337 continue;
1338 if (p->flags & IORESOURCE_BUSY &&
1339 p->flags & IORESOURCE_EXCLUSIVE) {
1340 err = 1;
1341 break;
1342 }
1343 }
1344 read_unlock(&resource_lock);
1345
1346 return err;
1347}
1348
1349static int __init strict_iomem(char *str)
1350{
1351 if (strstr(str, "relaxed"))
1352 strict_iomem_checks = 0;
1353 if (strstr(str, "strict"))
1354 strict_iomem_checks = 1;
1355 return 1;
1356}
1357
1358__setup("iomem=", strict_iomem);
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11
12#include <linux/export.h>
13#include <linux/errno.h>
14#include <linux/ioport.h>
15#include <linux/init.h>
16#include <linux/slab.h>
17#include <linux/spinlock.h>
18#include <linux/fs.h>
19#include <linux/proc_fs.h>
20#include <linux/sched.h>
21#include <linux/seq_file.h>
22#include <linux/device.h>
23#include <linux/pfn.h>
24#include <linux/mm.h>
25#include <linux/resource_ext.h>
26#include <asm/io.h>
27
28
29struct resource ioport_resource = {
30 .name = "PCI IO",
31 .start = 0,
32 .end = IO_SPACE_LIMIT,
33 .flags = IORESOURCE_IO,
34};
35EXPORT_SYMBOL(ioport_resource);
36
37struct resource iomem_resource = {
38 .name = "PCI mem",
39 .start = 0,
40 .end = -1,
41 .flags = IORESOURCE_MEM,
42};
43EXPORT_SYMBOL(iomem_resource);
44
45/* constraints to be met while allocating resources */
46struct resource_constraint {
47 resource_size_t min, max, align;
48 resource_size_t (*alignf)(void *, const struct resource *,
49 resource_size_t, resource_size_t);
50 void *alignf_data;
51};
52
53static DEFINE_RWLOCK(resource_lock);
54
55/*
56 * For memory hotplug, there is no way to free resource entries allocated
57 * by boot mem after the system is up. So for reusing the resource entry
58 * we need to remember the resource.
59 */
60static struct resource *bootmem_resource_free;
61static DEFINE_SPINLOCK(bootmem_resource_lock);
62
63static struct resource *next_resource(struct resource *p, bool sibling_only)
64{
65 /* Caller wants to traverse through siblings only */
66 if (sibling_only)
67 return p->sibling;
68
69 if (p->child)
70 return p->child;
71 while (!p->sibling && p->parent)
72 p = p->parent;
73 return p->sibling;
74}
75
76static void *r_next(struct seq_file *m, void *v, loff_t *pos)
77{
78 struct resource *p = v;
79 (*pos)++;
80 return (void *)next_resource(p, false);
81}
82
83#ifdef CONFIG_PROC_FS
84
85enum { MAX_IORES_LEVEL = 5 };
86
87static void *r_start(struct seq_file *m, loff_t *pos)
88 __acquires(resource_lock)
89{
90 struct resource *p = m->private;
91 loff_t l = 0;
92 read_lock(&resource_lock);
93 for (p = p->child; p && l < *pos; p = r_next(m, p, &l))
94 ;
95 return p;
96}
97
98static void r_stop(struct seq_file *m, void *v)
99 __releases(resource_lock)
100{
101 read_unlock(&resource_lock);
102}
103
104static int r_show(struct seq_file *m, void *v)
105{
106 struct resource *root = m->private;
107 struct resource *r = v, *p;
108 unsigned long long start, end;
109 int width = root->end < 0x10000 ? 4 : 8;
110 int depth;
111
112 for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent)
113 if (p->parent == root)
114 break;
115
116 if (file_ns_capable(m->file, &init_user_ns, CAP_SYS_ADMIN)) {
117 start = r->start;
118 end = r->end;
119 } else {
120 start = end = 0;
121 }
122
123 seq_printf(m, "%*s%0*llx-%0*llx : %s\n",
124 depth * 2, "",
125 width, start,
126 width, end,
127 r->name ? r->name : "<BAD>");
128 return 0;
129}
130
131static const struct seq_operations resource_op = {
132 .start = r_start,
133 .next = r_next,
134 .stop = r_stop,
135 .show = r_show,
136};
137
138static int ioports_open(struct inode *inode, struct file *file)
139{
140 int res = seq_open(file, &resource_op);
141 if (!res) {
142 struct seq_file *m = file->private_data;
143 m->private = &ioport_resource;
144 }
145 return res;
146}
147
148static int iomem_open(struct inode *inode, struct file *file)
149{
150 int res = seq_open(file, &resource_op);
151 if (!res) {
152 struct seq_file *m = file->private_data;
153 m->private = &iomem_resource;
154 }
155 return res;
156}
157
158static const struct file_operations proc_ioports_operations = {
159 .open = ioports_open,
160 .read = seq_read,
161 .llseek = seq_lseek,
162 .release = seq_release,
163};
164
165static const struct file_operations proc_iomem_operations = {
166 .open = iomem_open,
167 .read = seq_read,
168 .llseek = seq_lseek,
169 .release = seq_release,
170};
171
172static int __init ioresources_init(void)
173{
174 proc_create("ioports", 0, NULL, &proc_ioports_operations);
175 proc_create("iomem", 0, NULL, &proc_iomem_operations);
176 return 0;
177}
178__initcall(ioresources_init);
179
180#endif /* CONFIG_PROC_FS */
181
182static void free_resource(struct resource *res)
183{
184 if (!res)
185 return;
186
187 if (!PageSlab(virt_to_head_page(res))) {
188 spin_lock(&bootmem_resource_lock);
189 res->sibling = bootmem_resource_free;
190 bootmem_resource_free = res;
191 spin_unlock(&bootmem_resource_lock);
192 } else {
193 kfree(res);
194 }
195}
196
197static struct resource *alloc_resource(gfp_t flags)
198{
199 struct resource *res = NULL;
200
201 spin_lock(&bootmem_resource_lock);
202 if (bootmem_resource_free) {
203 res = bootmem_resource_free;
204 bootmem_resource_free = res->sibling;
205 }
206 spin_unlock(&bootmem_resource_lock);
207
208 if (res)
209 memset(res, 0, sizeof(struct resource));
210 else
211 res = kzalloc(sizeof(struct resource), flags);
212
213 return res;
214}
215
216/* Return the conflict entry if you can't request it */
217static struct resource * __request_resource(struct resource *root, struct resource *new)
218{
219 resource_size_t start = new->start;
220 resource_size_t end = new->end;
221 struct resource *tmp, **p;
222
223 if (end < start)
224 return root;
225 if (start < root->start)
226 return root;
227 if (end > root->end)
228 return root;
229 p = &root->child;
230 for (;;) {
231 tmp = *p;
232 if (!tmp || tmp->start > end) {
233 new->sibling = tmp;
234 *p = new;
235 new->parent = root;
236 return NULL;
237 }
238 p = &tmp->sibling;
239 if (tmp->end < start)
240 continue;
241 return tmp;
242 }
243}
244
245static int __release_resource(struct resource *old, bool release_child)
246{
247 struct resource *tmp, **p, *chd;
248
249 p = &old->parent->child;
250 for (;;) {
251 tmp = *p;
252 if (!tmp)
253 break;
254 if (tmp == old) {
255 if (release_child || !(tmp->child)) {
256 *p = tmp->sibling;
257 } else {
258 for (chd = tmp->child;; chd = chd->sibling) {
259 chd->parent = tmp->parent;
260 if (!(chd->sibling))
261 break;
262 }
263 *p = tmp->child;
264 chd->sibling = tmp->sibling;
265 }
266 old->parent = NULL;
267 return 0;
268 }
269 p = &tmp->sibling;
270 }
271 return -EINVAL;
272}
273
274static void __release_child_resources(struct resource *r)
275{
276 struct resource *tmp, *p;
277 resource_size_t size;
278
279 p = r->child;
280 r->child = NULL;
281 while (p) {
282 tmp = p;
283 p = p->sibling;
284
285 tmp->parent = NULL;
286 tmp->sibling = NULL;
287 __release_child_resources(tmp);
288
289 printk(KERN_DEBUG "release child resource %pR\n", tmp);
290 /* need to restore size, and keep flags */
291 size = resource_size(tmp);
292 tmp->start = 0;
293 tmp->end = size - 1;
294 }
295}
296
297void release_child_resources(struct resource *r)
298{
299 write_lock(&resource_lock);
300 __release_child_resources(r);
301 write_unlock(&resource_lock);
302}
303
304/**
305 * request_resource_conflict - request and reserve an I/O or memory resource
306 * @root: root resource descriptor
307 * @new: resource descriptor desired by caller
308 *
309 * Returns 0 for success, conflict resource on error.
310 */
311struct resource *request_resource_conflict(struct resource *root, struct resource *new)
312{
313 struct resource *conflict;
314
315 write_lock(&resource_lock);
316 conflict = __request_resource(root, new);
317 write_unlock(&resource_lock);
318 return conflict;
319}
320
321/**
322 * request_resource - request and reserve an I/O or memory resource
323 * @root: root resource descriptor
324 * @new: resource descriptor desired by caller
325 *
326 * Returns 0 for success, negative error code on error.
327 */
328int request_resource(struct resource *root, struct resource *new)
329{
330 struct resource *conflict;
331
332 conflict = request_resource_conflict(root, new);
333 return conflict ? -EBUSY : 0;
334}
335
336EXPORT_SYMBOL(request_resource);
337
338/**
339 * release_resource - release a previously reserved resource
340 * @old: resource pointer
341 */
342int release_resource(struct resource *old)
343{
344 int retval;
345
346 write_lock(&resource_lock);
347 retval = __release_resource(old, true);
348 write_unlock(&resource_lock);
349 return retval;
350}
351
352EXPORT_SYMBOL(release_resource);
353
354/*
355 * Finds the lowest iomem resource existing within [res->start.res->end).
356 * The caller must specify res->start, res->end, res->flags, and optionally
357 * desc. If found, returns 0, res is overwritten, if not found, returns -1.
358 * This function walks the whole tree and not just first level children until
359 * and unless first_level_children_only is true.
360 */
361static int find_next_iomem_res(struct resource *res, unsigned long desc,
362 bool first_level_children_only)
363{
364 resource_size_t start, end;
365 struct resource *p;
366 bool sibling_only = false;
367
368 BUG_ON(!res);
369
370 start = res->start;
371 end = res->end;
372 BUG_ON(start >= end);
373
374 if (first_level_children_only)
375 sibling_only = true;
376
377 read_lock(&resource_lock);
378
379 for (p = iomem_resource.child; p; p = next_resource(p, sibling_only)) {
380 if ((p->flags & res->flags) != res->flags)
381 continue;
382 if ((desc != IORES_DESC_NONE) && (desc != p->desc))
383 continue;
384 if (p->start > end) {
385 p = NULL;
386 break;
387 }
388 if ((p->end >= start) && (p->start < end))
389 break;
390 }
391
392 read_unlock(&resource_lock);
393 if (!p)
394 return -1;
395 /* copy data */
396 if (res->start < p->start)
397 res->start = p->start;
398 if (res->end > p->end)
399 res->end = p->end;
400 return 0;
401}
402
403/*
404 * Walks through iomem resources and calls func() with matching resource
405 * ranges. This walks through whole tree and not just first level children.
406 * All the memory ranges which overlap start,end and also match flags and
407 * desc are valid candidates.
408 *
409 * @desc: I/O resource descriptor. Use IORES_DESC_NONE to skip @desc check.
410 * @flags: I/O resource flags
411 * @start: start addr
412 * @end: end addr
413 *
414 * NOTE: For a new descriptor search, define a new IORES_DESC in
415 * <linux/ioport.h> and set it in 'desc' of a target resource entry.
416 */
417int walk_iomem_res_desc(unsigned long desc, unsigned long flags, u64 start,
418 u64 end, void *arg, int (*func)(u64, u64, void *))
419{
420 struct resource res;
421 u64 orig_end;
422 int ret = -1;
423
424 res.start = start;
425 res.end = end;
426 res.flags = flags;
427 orig_end = res.end;
428
429 while ((res.start < res.end) &&
430 (!find_next_iomem_res(&res, desc, false))) {
431
432 ret = (*func)(res.start, res.end, arg);
433 if (ret)
434 break;
435
436 res.start = res.end + 1;
437 res.end = orig_end;
438 }
439
440 return ret;
441}
442
443/*
444 * This function calls the @func callback against all memory ranges of type
445 * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY.
446 * Now, this function is only for System RAM, it deals with full ranges and
447 * not PFNs. If resources are not PFN-aligned, dealing with PFNs can truncate
448 * ranges.
449 */
450int walk_system_ram_res(u64 start, u64 end, void *arg,
451 int (*func)(u64, u64, void *))
452{
453 struct resource res;
454 u64 orig_end;
455 int ret = -1;
456
457 res.start = start;
458 res.end = end;
459 res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
460 orig_end = res.end;
461 while ((res.start < res.end) &&
462 (!find_next_iomem_res(&res, IORES_DESC_NONE, true))) {
463 ret = (*func)(res.start, res.end, arg);
464 if (ret)
465 break;
466 res.start = res.end + 1;
467 res.end = orig_end;
468 }
469 return ret;
470}
471
472#if !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
473
474/*
475 * This function calls the @func callback against all memory ranges of type
476 * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY.
477 * It is to be used only for System RAM.
478 */
479int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
480 void *arg, int (*func)(unsigned long, unsigned long, void *))
481{
482 struct resource res;
483 unsigned long pfn, end_pfn;
484 u64 orig_end;
485 int ret = -1;
486
487 res.start = (u64) start_pfn << PAGE_SHIFT;
488 res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1;
489 res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
490 orig_end = res.end;
491 while ((res.start < res.end) &&
492 (find_next_iomem_res(&res, IORES_DESC_NONE, true) >= 0)) {
493 pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT;
494 end_pfn = (res.end + 1) >> PAGE_SHIFT;
495 if (end_pfn > pfn)
496 ret = (*func)(pfn, end_pfn - pfn, arg);
497 if (ret)
498 break;
499 res.start = res.end + 1;
500 res.end = orig_end;
501 }
502 return ret;
503}
504
505#endif
506
507static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg)
508{
509 return 1;
510}
511/*
512 * This generic page_is_ram() returns true if specified address is
513 * registered as System RAM in iomem_resource list.
514 */
515int __weak page_is_ram(unsigned long pfn)
516{
517 return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1;
518}
519EXPORT_SYMBOL_GPL(page_is_ram);
520
521/**
522 * region_intersects() - determine intersection of region with known resources
523 * @start: region start address
524 * @size: size of region
525 * @flags: flags of resource (in iomem_resource)
526 * @desc: descriptor of resource (in iomem_resource) or IORES_DESC_NONE
527 *
528 * Check if the specified region partially overlaps or fully eclipses a
529 * resource identified by @flags and @desc (optional with IORES_DESC_NONE).
530 * Return REGION_DISJOINT if the region does not overlap @flags/@desc,
531 * return REGION_MIXED if the region overlaps @flags/@desc and another
532 * resource, and return REGION_INTERSECTS if the region overlaps @flags/@desc
533 * and no other defined resource. Note that REGION_INTERSECTS is also
534 * returned in the case when the specified region overlaps RAM and undefined
535 * memory holes.
536 *
537 * region_intersect() is used by memory remapping functions to ensure
538 * the user is not remapping RAM and is a vast speed up over walking
539 * through the resource table page by page.
540 */
541int region_intersects(resource_size_t start, size_t size, unsigned long flags,
542 unsigned long desc)
543{
544 resource_size_t end = start + size - 1;
545 int type = 0; int other = 0;
546 struct resource *p;
547
548 read_lock(&resource_lock);
549 for (p = iomem_resource.child; p ; p = p->sibling) {
550 bool is_type = (((p->flags & flags) == flags) &&
551 ((desc == IORES_DESC_NONE) ||
552 (desc == p->desc)));
553
554 if (start >= p->start && start <= p->end)
555 is_type ? type++ : other++;
556 if (end >= p->start && end <= p->end)
557 is_type ? type++ : other++;
558 if (p->start >= start && p->end <= end)
559 is_type ? type++ : other++;
560 }
561 read_unlock(&resource_lock);
562
563 if (other == 0)
564 return type ? REGION_INTERSECTS : REGION_DISJOINT;
565
566 if (type)
567 return REGION_MIXED;
568
569 return REGION_DISJOINT;
570}
571EXPORT_SYMBOL_GPL(region_intersects);
572
573void __weak arch_remove_reservations(struct resource *avail)
574{
575}
576
577static resource_size_t simple_align_resource(void *data,
578 const struct resource *avail,
579 resource_size_t size,
580 resource_size_t align)
581{
582 return avail->start;
583}
584
585static void resource_clip(struct resource *res, resource_size_t min,
586 resource_size_t max)
587{
588 if (res->start < min)
589 res->start = min;
590 if (res->end > max)
591 res->end = max;
592}
593
594/*
595 * Find empty slot in the resource tree with the given range and
596 * alignment constraints
597 */
598static int __find_resource(struct resource *root, struct resource *old,
599 struct resource *new,
600 resource_size_t size,
601 struct resource_constraint *constraint)
602{
603 struct resource *this = root->child;
604 struct resource tmp = *new, avail, alloc;
605
606 tmp.start = root->start;
607 /*
608 * Skip past an allocated resource that starts at 0, since the assignment
609 * of this->start - 1 to tmp->end below would cause an underflow.
610 */
611 if (this && this->start == root->start) {
612 tmp.start = (this == old) ? old->start : this->end + 1;
613 this = this->sibling;
614 }
615 for(;;) {
616 if (this)
617 tmp.end = (this == old) ? this->end : this->start - 1;
618 else
619 tmp.end = root->end;
620
621 if (tmp.end < tmp.start)
622 goto next;
623
624 resource_clip(&tmp, constraint->min, constraint->max);
625 arch_remove_reservations(&tmp);
626
627 /* Check for overflow after ALIGN() */
628 avail.start = ALIGN(tmp.start, constraint->align);
629 avail.end = tmp.end;
630 avail.flags = new->flags & ~IORESOURCE_UNSET;
631 if (avail.start >= tmp.start) {
632 alloc.flags = avail.flags;
633 alloc.start = constraint->alignf(constraint->alignf_data, &avail,
634 size, constraint->align);
635 alloc.end = alloc.start + size - 1;
636 if (resource_contains(&avail, &alloc)) {
637 new->start = alloc.start;
638 new->end = alloc.end;
639 return 0;
640 }
641 }
642
643next: if (!this || this->end == root->end)
644 break;
645
646 if (this != old)
647 tmp.start = this->end + 1;
648 this = this->sibling;
649 }
650 return -EBUSY;
651}
652
653/*
654 * Find empty slot in the resource tree given range and alignment.
655 */
656static int find_resource(struct resource *root, struct resource *new,
657 resource_size_t size,
658 struct resource_constraint *constraint)
659{
660 return __find_resource(root, NULL, new, size, constraint);
661}
662
663/**
664 * reallocate_resource - allocate a slot in the resource tree given range & alignment.
665 * The resource will be relocated if the new size cannot be reallocated in the
666 * current location.
667 *
668 * @root: root resource descriptor
669 * @old: resource descriptor desired by caller
670 * @newsize: new size of the resource descriptor
671 * @constraint: the size and alignment constraints to be met.
672 */
673static int reallocate_resource(struct resource *root, struct resource *old,
674 resource_size_t newsize,
675 struct resource_constraint *constraint)
676{
677 int err=0;
678 struct resource new = *old;
679 struct resource *conflict;
680
681 write_lock(&resource_lock);
682
683 if ((err = __find_resource(root, old, &new, newsize, constraint)))
684 goto out;
685
686 if (resource_contains(&new, old)) {
687 old->start = new.start;
688 old->end = new.end;
689 goto out;
690 }
691
692 if (old->child) {
693 err = -EBUSY;
694 goto out;
695 }
696
697 if (resource_contains(old, &new)) {
698 old->start = new.start;
699 old->end = new.end;
700 } else {
701 __release_resource(old, true);
702 *old = new;
703 conflict = __request_resource(root, old);
704 BUG_ON(conflict);
705 }
706out:
707 write_unlock(&resource_lock);
708 return err;
709}
710
711
712/**
713 * allocate_resource - allocate empty slot in the resource tree given range & alignment.
714 * The resource will be reallocated with a new size if it was already allocated
715 * @root: root resource descriptor
716 * @new: resource descriptor desired by caller
717 * @size: requested resource region size
718 * @min: minimum boundary to allocate
719 * @max: maximum boundary to allocate
720 * @align: alignment requested, in bytes
721 * @alignf: alignment function, optional, called if not NULL
722 * @alignf_data: arbitrary data to pass to the @alignf function
723 */
724int allocate_resource(struct resource *root, struct resource *new,
725 resource_size_t size, resource_size_t min,
726 resource_size_t max, resource_size_t align,
727 resource_size_t (*alignf)(void *,
728 const struct resource *,
729 resource_size_t,
730 resource_size_t),
731 void *alignf_data)
732{
733 int err;
734 struct resource_constraint constraint;
735
736 if (!alignf)
737 alignf = simple_align_resource;
738
739 constraint.min = min;
740 constraint.max = max;
741 constraint.align = align;
742 constraint.alignf = alignf;
743 constraint.alignf_data = alignf_data;
744
745 if ( new->parent ) {
746 /* resource is already allocated, try reallocating with
747 the new constraints */
748 return reallocate_resource(root, new, size, &constraint);
749 }
750
751 write_lock(&resource_lock);
752 err = find_resource(root, new, size, &constraint);
753 if (err >= 0 && __request_resource(root, new))
754 err = -EBUSY;
755 write_unlock(&resource_lock);
756 return err;
757}
758
759EXPORT_SYMBOL(allocate_resource);
760
761/**
762 * lookup_resource - find an existing resource by a resource start address
763 * @root: root resource descriptor
764 * @start: resource start address
765 *
766 * Returns a pointer to the resource if found, NULL otherwise
767 */
768struct resource *lookup_resource(struct resource *root, resource_size_t start)
769{
770 struct resource *res;
771
772 read_lock(&resource_lock);
773 for (res = root->child; res; res = res->sibling) {
774 if (res->start == start)
775 break;
776 }
777 read_unlock(&resource_lock);
778
779 return res;
780}
781
782/*
783 * Insert a resource into the resource tree. If successful, return NULL,
784 * otherwise return the conflicting resource (compare to __request_resource())
785 */
786static struct resource * __insert_resource(struct resource *parent, struct resource *new)
787{
788 struct resource *first, *next;
789
790 for (;; parent = first) {
791 first = __request_resource(parent, new);
792 if (!first)
793 return first;
794
795 if (first == parent)
796 return first;
797 if (WARN_ON(first == new)) /* duplicated insertion */
798 return first;
799
800 if ((first->start > new->start) || (first->end < new->end))
801 break;
802 if ((first->start == new->start) && (first->end == new->end))
803 break;
804 }
805
806 for (next = first; ; next = next->sibling) {
807 /* Partial overlap? Bad, and unfixable */
808 if (next->start < new->start || next->end > new->end)
809 return next;
810 if (!next->sibling)
811 break;
812 if (next->sibling->start > new->end)
813 break;
814 }
815
816 new->parent = parent;
817 new->sibling = next->sibling;
818 new->child = first;
819
820 next->sibling = NULL;
821 for (next = first; next; next = next->sibling)
822 next->parent = new;
823
824 if (parent->child == first) {
825 parent->child = new;
826 } else {
827 next = parent->child;
828 while (next->sibling != first)
829 next = next->sibling;
830 next->sibling = new;
831 }
832 return NULL;
833}
834
835/**
836 * insert_resource_conflict - Inserts resource in the resource tree
837 * @parent: parent of the new resource
838 * @new: new resource to insert
839 *
840 * Returns 0 on success, conflict resource if the resource can't be inserted.
841 *
842 * This function is equivalent to request_resource_conflict when no conflict
843 * happens. If a conflict happens, and the conflicting resources
844 * entirely fit within the range of the new resource, then the new
845 * resource is inserted and the conflicting resources become children of
846 * the new resource.
847 *
848 * This function is intended for producers of resources, such as FW modules
849 * and bus drivers.
850 */
851struct resource *insert_resource_conflict(struct resource *parent, struct resource *new)
852{
853 struct resource *conflict;
854
855 write_lock(&resource_lock);
856 conflict = __insert_resource(parent, new);
857 write_unlock(&resource_lock);
858 return conflict;
859}
860
861/**
862 * insert_resource - Inserts a resource in the resource tree
863 * @parent: parent of the new resource
864 * @new: new resource to insert
865 *
866 * Returns 0 on success, -EBUSY if the resource can't be inserted.
867 *
868 * This function is intended for producers of resources, such as FW modules
869 * and bus drivers.
870 */
871int insert_resource(struct resource *parent, struct resource *new)
872{
873 struct resource *conflict;
874
875 conflict = insert_resource_conflict(parent, new);
876 return conflict ? -EBUSY : 0;
877}
878EXPORT_SYMBOL_GPL(insert_resource);
879
880/**
881 * insert_resource_expand_to_fit - Insert a resource into the resource tree
882 * @root: root resource descriptor
883 * @new: new resource to insert
884 *
885 * Insert a resource into the resource tree, possibly expanding it in order
886 * to make it encompass any conflicting resources.
887 */
888void insert_resource_expand_to_fit(struct resource *root, struct resource *new)
889{
890 if (new->parent)
891 return;
892
893 write_lock(&resource_lock);
894 for (;;) {
895 struct resource *conflict;
896
897 conflict = __insert_resource(root, new);
898 if (!conflict)
899 break;
900 if (conflict == root)
901 break;
902
903 /* Ok, expand resource to cover the conflict, then try again .. */
904 if (conflict->start < new->start)
905 new->start = conflict->start;
906 if (conflict->end > new->end)
907 new->end = conflict->end;
908
909 printk("Expanded resource %s due to conflict with %s\n", new->name, conflict->name);
910 }
911 write_unlock(&resource_lock);
912}
913
914/**
915 * remove_resource - Remove a resource in the resource tree
916 * @old: resource to remove
917 *
918 * Returns 0 on success, -EINVAL if the resource is not valid.
919 *
920 * This function removes a resource previously inserted by insert_resource()
921 * or insert_resource_conflict(), and moves the children (if any) up to
922 * where they were before. insert_resource() and insert_resource_conflict()
923 * insert a new resource, and move any conflicting resources down to the
924 * children of the new resource.
925 *
926 * insert_resource(), insert_resource_conflict() and remove_resource() are
927 * intended for producers of resources, such as FW modules and bus drivers.
928 */
929int remove_resource(struct resource *old)
930{
931 int retval;
932
933 write_lock(&resource_lock);
934 retval = __release_resource(old, false);
935 write_unlock(&resource_lock);
936 return retval;
937}
938EXPORT_SYMBOL_GPL(remove_resource);
939
940static int __adjust_resource(struct resource *res, resource_size_t start,
941 resource_size_t size)
942{
943 struct resource *tmp, *parent = res->parent;
944 resource_size_t end = start + size - 1;
945 int result = -EBUSY;
946
947 if (!parent)
948 goto skip;
949
950 if ((start < parent->start) || (end > parent->end))
951 goto out;
952
953 if (res->sibling && (res->sibling->start <= end))
954 goto out;
955
956 tmp = parent->child;
957 if (tmp != res) {
958 while (tmp->sibling != res)
959 tmp = tmp->sibling;
960 if (start <= tmp->end)
961 goto out;
962 }
963
964skip:
965 for (tmp = res->child; tmp; tmp = tmp->sibling)
966 if ((tmp->start < start) || (tmp->end > end))
967 goto out;
968
969 res->start = start;
970 res->end = end;
971 result = 0;
972
973 out:
974 return result;
975}
976
977/**
978 * adjust_resource - modify a resource's start and size
979 * @res: resource to modify
980 * @start: new start value
981 * @size: new size
982 *
983 * Given an existing resource, change its start and size to match the
984 * arguments. Returns 0 on success, -EBUSY if it can't fit.
985 * Existing children of the resource are assumed to be immutable.
986 */
987int adjust_resource(struct resource *res, resource_size_t start,
988 resource_size_t size)
989{
990 int result;
991
992 write_lock(&resource_lock);
993 result = __adjust_resource(res, start, size);
994 write_unlock(&resource_lock);
995 return result;
996}
997EXPORT_SYMBOL(adjust_resource);
998
999static void __init __reserve_region_with_split(struct resource *root,
1000 resource_size_t start, resource_size_t end,
1001 const char *name)
1002{
1003 struct resource *parent = root;
1004 struct resource *conflict;
1005 struct resource *res = alloc_resource(GFP_ATOMIC);
1006 struct resource *next_res = NULL;
1007
1008 if (!res)
1009 return;
1010
1011 res->name = name;
1012 res->start = start;
1013 res->end = end;
1014 res->flags = IORESOURCE_BUSY;
1015 res->desc = IORES_DESC_NONE;
1016
1017 while (1) {
1018
1019 conflict = __request_resource(parent, res);
1020 if (!conflict) {
1021 if (!next_res)
1022 break;
1023 res = next_res;
1024 next_res = NULL;
1025 continue;
1026 }
1027
1028 /* conflict covered whole area */
1029 if (conflict->start <= res->start &&
1030 conflict->end >= res->end) {
1031 free_resource(res);
1032 WARN_ON(next_res);
1033 break;
1034 }
1035
1036 /* failed, split and try again */
1037 if (conflict->start > res->start) {
1038 end = res->end;
1039 res->end = conflict->start - 1;
1040 if (conflict->end < end) {
1041 next_res = alloc_resource(GFP_ATOMIC);
1042 if (!next_res) {
1043 free_resource(res);
1044 break;
1045 }
1046 next_res->name = name;
1047 next_res->start = conflict->end + 1;
1048 next_res->end = end;
1049 next_res->flags = IORESOURCE_BUSY;
1050 next_res->desc = IORES_DESC_NONE;
1051 }
1052 } else {
1053 res->start = conflict->end + 1;
1054 }
1055 }
1056
1057}
1058
1059void __init reserve_region_with_split(struct resource *root,
1060 resource_size_t start, resource_size_t end,
1061 const char *name)
1062{
1063 int abort = 0;
1064
1065 write_lock(&resource_lock);
1066 if (root->start > start || root->end < end) {
1067 pr_err("requested range [0x%llx-0x%llx] not in root %pr\n",
1068 (unsigned long long)start, (unsigned long long)end,
1069 root);
1070 if (start > root->end || end < root->start)
1071 abort = 1;
1072 else {
1073 if (end > root->end)
1074 end = root->end;
1075 if (start < root->start)
1076 start = root->start;
1077 pr_err("fixing request to [0x%llx-0x%llx]\n",
1078 (unsigned long long)start,
1079 (unsigned long long)end);
1080 }
1081 dump_stack();
1082 }
1083 if (!abort)
1084 __reserve_region_with_split(root, start, end, name);
1085 write_unlock(&resource_lock);
1086}
1087
1088/**
1089 * resource_alignment - calculate resource's alignment
1090 * @res: resource pointer
1091 *
1092 * Returns alignment on success, 0 (invalid alignment) on failure.
1093 */
1094resource_size_t resource_alignment(struct resource *res)
1095{
1096 switch (res->flags & (IORESOURCE_SIZEALIGN | IORESOURCE_STARTALIGN)) {
1097 case IORESOURCE_SIZEALIGN:
1098 return resource_size(res);
1099 case IORESOURCE_STARTALIGN:
1100 return res->start;
1101 default:
1102 return 0;
1103 }
1104}
1105
1106/*
1107 * This is compatibility stuff for IO resources.
1108 *
1109 * Note how this, unlike the above, knows about
1110 * the IO flag meanings (busy etc).
1111 *
1112 * request_region creates a new busy region.
1113 *
1114 * release_region releases a matching busy region.
1115 */
1116
1117static DECLARE_WAIT_QUEUE_HEAD(muxed_resource_wait);
1118
1119/**
1120 * __request_region - create a new busy resource region
1121 * @parent: parent resource descriptor
1122 * @start: resource start address
1123 * @n: resource region size
1124 * @name: reserving caller's ID string
1125 * @flags: IO resource flags
1126 */
1127struct resource * __request_region(struct resource *parent,
1128 resource_size_t start, resource_size_t n,
1129 const char *name, int flags)
1130{
1131 DECLARE_WAITQUEUE(wait, current);
1132 struct resource *res = alloc_resource(GFP_KERNEL);
1133
1134 if (!res)
1135 return NULL;
1136
1137 res->name = name;
1138 res->start = start;
1139 res->end = start + n - 1;
1140
1141 write_lock(&resource_lock);
1142
1143 for (;;) {
1144 struct resource *conflict;
1145
1146 res->flags = resource_type(parent) | resource_ext_type(parent);
1147 res->flags |= IORESOURCE_BUSY | flags;
1148 res->desc = parent->desc;
1149
1150 conflict = __request_resource(parent, res);
1151 if (!conflict)
1152 break;
1153 if (conflict != parent) {
1154 if (!(conflict->flags & IORESOURCE_BUSY)) {
1155 parent = conflict;
1156 continue;
1157 }
1158 }
1159 if (conflict->flags & flags & IORESOURCE_MUXED) {
1160 add_wait_queue(&muxed_resource_wait, &wait);
1161 write_unlock(&resource_lock);
1162 set_current_state(TASK_UNINTERRUPTIBLE);
1163 schedule();
1164 remove_wait_queue(&muxed_resource_wait, &wait);
1165 write_lock(&resource_lock);
1166 continue;
1167 }
1168 /* Uhhuh, that didn't work out.. */
1169 free_resource(res);
1170 res = NULL;
1171 break;
1172 }
1173 write_unlock(&resource_lock);
1174 return res;
1175}
1176EXPORT_SYMBOL(__request_region);
1177
1178/**
1179 * __release_region - release a previously reserved resource region
1180 * @parent: parent resource descriptor
1181 * @start: resource start address
1182 * @n: resource region size
1183 *
1184 * The described resource region must match a currently busy region.
1185 */
1186void __release_region(struct resource *parent, resource_size_t start,
1187 resource_size_t n)
1188{
1189 struct resource **p;
1190 resource_size_t end;
1191
1192 p = &parent->child;
1193 end = start + n - 1;
1194
1195 write_lock(&resource_lock);
1196
1197 for (;;) {
1198 struct resource *res = *p;
1199
1200 if (!res)
1201 break;
1202 if (res->start <= start && res->end >= end) {
1203 if (!(res->flags & IORESOURCE_BUSY)) {
1204 p = &res->child;
1205 continue;
1206 }
1207 if (res->start != start || res->end != end)
1208 break;
1209 *p = res->sibling;
1210 write_unlock(&resource_lock);
1211 if (res->flags & IORESOURCE_MUXED)
1212 wake_up(&muxed_resource_wait);
1213 free_resource(res);
1214 return;
1215 }
1216 p = &res->sibling;
1217 }
1218
1219 write_unlock(&resource_lock);
1220
1221 printk(KERN_WARNING "Trying to free nonexistent resource "
1222 "<%016llx-%016llx>\n", (unsigned long long)start,
1223 (unsigned long long)end);
1224}
1225EXPORT_SYMBOL(__release_region);
1226
1227#ifdef CONFIG_MEMORY_HOTREMOVE
1228/**
1229 * release_mem_region_adjustable - release a previously reserved memory region
1230 * @parent: parent resource descriptor
1231 * @start: resource start address
1232 * @size: resource region size
1233 *
1234 * This interface is intended for memory hot-delete. The requested region
1235 * is released from a currently busy memory resource. The requested region
1236 * must either match exactly or fit into a single busy resource entry. In
1237 * the latter case, the remaining resource is adjusted accordingly.
1238 * Existing children of the busy memory resource must be immutable in the
1239 * request.
1240 *
1241 * Note:
1242 * - Additional release conditions, such as overlapping region, can be
1243 * supported after they are confirmed as valid cases.
1244 * - When a busy memory resource gets split into two entries, the code
1245 * assumes that all children remain in the lower address entry for
1246 * simplicity. Enhance this logic when necessary.
1247 */
1248int release_mem_region_adjustable(struct resource *parent,
1249 resource_size_t start, resource_size_t size)
1250{
1251 struct resource **p;
1252 struct resource *res;
1253 struct resource *new_res;
1254 resource_size_t end;
1255 int ret = -EINVAL;
1256
1257 end = start + size - 1;
1258 if ((start < parent->start) || (end > parent->end))
1259 return ret;
1260
1261 /* The alloc_resource() result gets checked later */
1262 new_res = alloc_resource(GFP_KERNEL);
1263
1264 p = &parent->child;
1265 write_lock(&resource_lock);
1266
1267 while ((res = *p)) {
1268 if (res->start >= end)
1269 break;
1270
1271 /* look for the next resource if it does not fit into */
1272 if (res->start > start || res->end < end) {
1273 p = &res->sibling;
1274 continue;
1275 }
1276
1277 if (!(res->flags & IORESOURCE_MEM))
1278 break;
1279
1280 if (!(res->flags & IORESOURCE_BUSY)) {
1281 p = &res->child;
1282 continue;
1283 }
1284
1285 /* found the target resource; let's adjust accordingly */
1286 if (res->start == start && res->end == end) {
1287 /* free the whole entry */
1288 *p = res->sibling;
1289 free_resource(res);
1290 ret = 0;
1291 } else if (res->start == start && res->end != end) {
1292 /* adjust the start */
1293 ret = __adjust_resource(res, end + 1,
1294 res->end - end);
1295 } else if (res->start != start && res->end == end) {
1296 /* adjust the end */
1297 ret = __adjust_resource(res, res->start,
1298 start - res->start);
1299 } else {
1300 /* split into two entries */
1301 if (!new_res) {
1302 ret = -ENOMEM;
1303 break;
1304 }
1305 new_res->name = res->name;
1306 new_res->start = end + 1;
1307 new_res->end = res->end;
1308 new_res->flags = res->flags;
1309 new_res->desc = res->desc;
1310 new_res->parent = res->parent;
1311 new_res->sibling = res->sibling;
1312 new_res->child = NULL;
1313
1314 ret = __adjust_resource(res, res->start,
1315 start - res->start);
1316 if (ret)
1317 break;
1318 res->sibling = new_res;
1319 new_res = NULL;
1320 }
1321
1322 break;
1323 }
1324
1325 write_unlock(&resource_lock);
1326 free_resource(new_res);
1327 return ret;
1328}
1329#endif /* CONFIG_MEMORY_HOTREMOVE */
1330
1331/*
1332 * Managed region resource
1333 */
1334static void devm_resource_release(struct device *dev, void *ptr)
1335{
1336 struct resource **r = ptr;
1337
1338 release_resource(*r);
1339}
1340
1341/**
1342 * devm_request_resource() - request and reserve an I/O or memory resource
1343 * @dev: device for which to request the resource
1344 * @root: root of the resource tree from which to request the resource
1345 * @new: descriptor of the resource to request
1346 *
1347 * This is a device-managed version of request_resource(). There is usually
1348 * no need to release resources requested by this function explicitly since
1349 * that will be taken care of when the device is unbound from its driver.
1350 * If for some reason the resource needs to be released explicitly, because
1351 * of ordering issues for example, drivers must call devm_release_resource()
1352 * rather than the regular release_resource().
1353 *
1354 * When a conflict is detected between any existing resources and the newly
1355 * requested resource, an error message will be printed.
1356 *
1357 * Returns 0 on success or a negative error code on failure.
1358 */
1359int devm_request_resource(struct device *dev, struct resource *root,
1360 struct resource *new)
1361{
1362 struct resource *conflict, **ptr;
1363
1364 ptr = devres_alloc(devm_resource_release, sizeof(*ptr), GFP_KERNEL);
1365 if (!ptr)
1366 return -ENOMEM;
1367
1368 *ptr = new;
1369
1370 conflict = request_resource_conflict(root, new);
1371 if (conflict) {
1372 dev_err(dev, "resource collision: %pR conflicts with %s %pR\n",
1373 new, conflict->name, conflict);
1374 devres_free(ptr);
1375 return -EBUSY;
1376 }
1377
1378 devres_add(dev, ptr);
1379 return 0;
1380}
1381EXPORT_SYMBOL(devm_request_resource);
1382
1383static int devm_resource_match(struct device *dev, void *res, void *data)
1384{
1385 struct resource **ptr = res;
1386
1387 return *ptr == data;
1388}
1389
1390/**
1391 * devm_release_resource() - release a previously requested resource
1392 * @dev: device for which to release the resource
1393 * @new: descriptor of the resource to release
1394 *
1395 * Releases a resource previously requested using devm_request_resource().
1396 */
1397void devm_release_resource(struct device *dev, struct resource *new)
1398{
1399 WARN_ON(devres_release(dev, devm_resource_release, devm_resource_match,
1400 new));
1401}
1402EXPORT_SYMBOL(devm_release_resource);
1403
1404struct region_devres {
1405 struct resource *parent;
1406 resource_size_t start;
1407 resource_size_t n;
1408};
1409
1410static void devm_region_release(struct device *dev, void *res)
1411{
1412 struct region_devres *this = res;
1413
1414 __release_region(this->parent, this->start, this->n);
1415}
1416
1417static int devm_region_match(struct device *dev, void *res, void *match_data)
1418{
1419 struct region_devres *this = res, *match = match_data;
1420
1421 return this->parent == match->parent &&
1422 this->start == match->start && this->n == match->n;
1423}
1424
1425struct resource * __devm_request_region(struct device *dev,
1426 struct resource *parent, resource_size_t start,
1427 resource_size_t n, const char *name)
1428{
1429 struct region_devres *dr = NULL;
1430 struct resource *res;
1431
1432 dr = devres_alloc(devm_region_release, sizeof(struct region_devres),
1433 GFP_KERNEL);
1434 if (!dr)
1435 return NULL;
1436
1437 dr->parent = parent;
1438 dr->start = start;
1439 dr->n = n;
1440
1441 res = __request_region(parent, start, n, name, 0);
1442 if (res)
1443 devres_add(dev, dr);
1444 else
1445 devres_free(dr);
1446
1447 return res;
1448}
1449EXPORT_SYMBOL(__devm_request_region);
1450
1451void __devm_release_region(struct device *dev, struct resource *parent,
1452 resource_size_t start, resource_size_t n)
1453{
1454 struct region_devres match_data = { parent, start, n };
1455
1456 __release_region(parent, start, n);
1457 WARN_ON(devres_destroy(dev, devm_region_release, devm_region_match,
1458 &match_data));
1459}
1460EXPORT_SYMBOL(__devm_release_region);
1461
1462/*
1463 * Called from init/main.c to reserve IO ports.
1464 */
1465#define MAXRESERVE 4
1466static int __init reserve_setup(char *str)
1467{
1468 static int reserved;
1469 static struct resource reserve[MAXRESERVE];
1470
1471 for (;;) {
1472 unsigned int io_start, io_num;
1473 int x = reserved;
1474
1475 if (get_option (&str, &io_start) != 2)
1476 break;
1477 if (get_option (&str, &io_num) == 0)
1478 break;
1479 if (x < MAXRESERVE) {
1480 struct resource *res = reserve + x;
1481 res->name = "reserved";
1482 res->start = io_start;
1483 res->end = io_start + io_num - 1;
1484 res->flags = IORESOURCE_BUSY;
1485 res->desc = IORES_DESC_NONE;
1486 res->child = NULL;
1487 if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, res) == 0)
1488 reserved = x+1;
1489 }
1490 }
1491 return 1;
1492}
1493
1494__setup("reserve=", reserve_setup);
1495
1496/*
1497 * Check if the requested addr and size spans more than any slot in the
1498 * iomem resource tree.
1499 */
1500int iomem_map_sanity_check(resource_size_t addr, unsigned long size)
1501{
1502 struct resource *p = &iomem_resource;
1503 int err = 0;
1504 loff_t l;
1505
1506 read_lock(&resource_lock);
1507 for (p = p->child; p ; p = r_next(NULL, p, &l)) {
1508 /*
1509 * We can probably skip the resources without
1510 * IORESOURCE_IO attribute?
1511 */
1512 if (p->start >= addr + size)
1513 continue;
1514 if (p->end < addr)
1515 continue;
1516 if (PFN_DOWN(p->start) <= PFN_DOWN(addr) &&
1517 PFN_DOWN(p->end) >= PFN_DOWN(addr + size - 1))
1518 continue;
1519 /*
1520 * if a resource is "BUSY", it's not a hardware resource
1521 * but a driver mapping of such a resource; we don't want
1522 * to warn for those; some drivers legitimately map only
1523 * partial hardware resources. (example: vesafb)
1524 */
1525 if (p->flags & IORESOURCE_BUSY)
1526 continue;
1527
1528 printk(KERN_WARNING "resource sanity check: requesting [mem %#010llx-%#010llx], which spans more than %s %pR\n",
1529 (unsigned long long)addr,
1530 (unsigned long long)(addr + size - 1),
1531 p->name, p);
1532 err = -1;
1533 break;
1534 }
1535 read_unlock(&resource_lock);
1536
1537 return err;
1538}
1539
1540#ifdef CONFIG_STRICT_DEVMEM
1541static int strict_iomem_checks = 1;
1542#else
1543static int strict_iomem_checks;
1544#endif
1545
1546/*
1547 * check if an address is reserved in the iomem resource tree
1548 * returns 1 if reserved, 0 if not reserved.
1549 */
1550int iomem_is_exclusive(u64 addr)
1551{
1552 struct resource *p = &iomem_resource;
1553 int err = 0;
1554 loff_t l;
1555 int size = PAGE_SIZE;
1556
1557 if (!strict_iomem_checks)
1558 return 0;
1559
1560 addr = addr & PAGE_MASK;
1561
1562 read_lock(&resource_lock);
1563 for (p = p->child; p ; p = r_next(NULL, p, &l)) {
1564 /*
1565 * We can probably skip the resources without
1566 * IORESOURCE_IO attribute?
1567 */
1568 if (p->start >= addr + size)
1569 break;
1570 if (p->end < addr)
1571 continue;
1572 /*
1573 * A resource is exclusive if IORESOURCE_EXCLUSIVE is set
1574 * or CONFIG_IO_STRICT_DEVMEM is enabled and the
1575 * resource is busy.
1576 */
1577 if ((p->flags & IORESOURCE_BUSY) == 0)
1578 continue;
1579 if (IS_ENABLED(CONFIG_IO_STRICT_DEVMEM)
1580 || p->flags & IORESOURCE_EXCLUSIVE) {
1581 err = 1;
1582 break;
1583 }
1584 }
1585 read_unlock(&resource_lock);
1586
1587 return err;
1588}
1589
1590struct resource_entry *resource_list_create_entry(struct resource *res,
1591 size_t extra_size)
1592{
1593 struct resource_entry *entry;
1594
1595 entry = kzalloc(sizeof(*entry) + extra_size, GFP_KERNEL);
1596 if (entry) {
1597 INIT_LIST_HEAD(&entry->node);
1598 entry->res = res ? res : &entry->__res;
1599 }
1600
1601 return entry;
1602}
1603EXPORT_SYMBOL(resource_list_create_entry);
1604
1605void resource_list_free(struct list_head *head)
1606{
1607 struct resource_entry *entry, *tmp;
1608
1609 list_for_each_entry_safe(entry, tmp, head, node)
1610 resource_list_destroy_entry(entry);
1611}
1612EXPORT_SYMBOL(resource_list_free);
1613
1614static int __init strict_iomem(char *str)
1615{
1616 if (strstr(str, "relaxed"))
1617 strict_iomem_checks = 0;
1618 if (strstr(str, "strict"))
1619 strict_iomem_checks = 1;
1620 return 1;
1621}
1622
1623__setup("iomem=", strict_iomem);