Line data Source code
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 :
28 : struct resource ioport_resource = {
29 : .name = "PCI IO",
30 : .start = 0,
31 : .end = IO_SPACE_LIMIT,
32 : .flags = IORESOURCE_IO,
33 : };
34 : EXPORT_SYMBOL(ioport_resource);
35 :
36 : struct resource iomem_resource = {
37 : .name = "PCI mem",
38 : .start = 0,
39 : .end = -1,
40 : .flags = IORESOURCE_MEM,
41 : };
42 : EXPORT_SYMBOL(iomem_resource);
43 :
44 : /* constraints to be met while allocating resources */
45 : struct 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 :
52 : static 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 : */
59 : static struct resource *bootmem_resource_free;
60 : static DEFINE_SPINLOCK(bootmem_resource_lock);
61 :
62 : static struct resource *next_resource(struct resource *p, bool sibling_only)
63 : {
64 : /* Caller wants to traverse through siblings only */
65 0 : if (sibling_only)
66 0 : return p->sibling;
67 :
68 0 : if (p->child)
69 : return p->child;
70 0 : while (!p->sibling && p->parent)
71 : p = p->parent;
72 : return p->sibling;
73 : }
74 :
75 0 : static void *r_next(struct seq_file *m, void *v, loff_t *pos)
76 : {
77 : struct resource *p = v;
78 0 : (*pos)++;
79 0 : return (void *)next_resource(p, false);
80 : }
81 :
82 : #ifdef CONFIG_PROC_FS
83 :
84 : enum { MAX_IORES_LEVEL = 5 };
85 :
86 0 : static void *r_start(struct seq_file *m, loff_t *pos)
87 : __acquires(resource_lock)
88 : {
89 0 : struct resource *p = m->private;
90 : loff_t l = 0;
91 0 : read_lock(&resource_lock);
92 0 : for (p = p->child; p && l < *pos; p = r_next(m, p, &l))
93 : ;
94 0 : return p;
95 : }
96 :
97 0 : static void r_stop(struct seq_file *m, void *v)
98 : __releases(resource_lock)
99 : {
100 0 : read_unlock(&resource_lock);
101 0 : }
102 :
103 0 : static int r_show(struct seq_file *m, void *v)
104 : {
105 0 : struct resource *root = m->private;
106 : struct resource *r = v, *p;
107 0 : int width = root->end < 0x10000 ? 4 : 8;
108 : int depth;
109 :
110 0 : for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent)
111 0 : if (p->parent == root)
112 : break;
113 0 : seq_printf(m, "%*s%0*llx-%0*llx : %s\n",
114 : depth * 2, "",
115 0 : width, (unsigned long long) r->start,
116 0 : width, (unsigned long long) r->end,
117 0 : r->name ? r->name : "<BAD>");
118 0 : return 0;
119 : }
120 :
121 : static const struct seq_operations resource_op = {
122 : .start = r_start,
123 : .next = r_next,
124 : .stop = r_stop,
125 : .show = r_show,
126 : };
127 :
128 0 : static int ioports_open(struct inode *inode, struct file *file)
129 : {
130 0 : int res = seq_open(file, &resource_op);
131 0 : if (!res) {
132 0 : struct seq_file *m = file->private_data;
133 0 : m->private = &ioport_resource;
134 : }
135 0 : return res;
136 : }
137 :
138 0 : static int iomem_open(struct inode *inode, struct file *file)
139 : {
140 0 : int res = seq_open(file, &resource_op);
141 0 : if (!res) {
142 0 : struct seq_file *m = file->private_data;
143 0 : m->private = &iomem_resource;
144 : }
145 0 : return res;
146 : }
147 :
148 : static const struct file_operations proc_ioports_operations = {
149 : .open = ioports_open,
150 : .read = seq_read,
151 : .llseek = seq_lseek,
152 : .release = seq_release,
153 : };
154 :
155 : static const struct file_operations proc_iomem_operations = {
156 : .open = iomem_open,
157 : .read = seq_read,
158 : .llseek = seq_lseek,
159 : .release = seq_release,
160 : };
161 :
162 1 : static int __init ioresources_init(void)
163 : {
164 : proc_create("ioports", 0, NULL, &proc_ioports_operations);
165 : proc_create("iomem", 0, NULL, &proc_iomem_operations);
166 1 : return 0;
167 : }
168 : __initcall(ioresources_init);
169 :
170 : #endif /* CONFIG_PROC_FS */
171 :
172 0 : static void free_resource(struct resource *res)
173 : {
174 0 : if (!res)
175 0 : return;
176 :
177 0 : if (!PageSlab(virt_to_head_page(res))) {
178 : spin_lock(&bootmem_resource_lock);
179 0 : res->sibling = bootmem_resource_free;
180 0 : bootmem_resource_free = res;
181 : spin_unlock(&bootmem_resource_lock);
182 : } else {
183 0 : kfree(res);
184 : }
185 : }
186 :
187 6 : static struct resource *alloc_resource(gfp_t flags)
188 : {
189 : struct resource *res = NULL;
190 :
191 : spin_lock(&bootmem_resource_lock);
192 6 : if (bootmem_resource_free) {
193 : res = bootmem_resource_free;
194 0 : bootmem_resource_free = res->sibling;
195 : }
196 : spin_unlock(&bootmem_resource_lock);
197 :
198 6 : if (res)
199 0 : memset(res, 0, sizeof(struct resource));
200 : else
201 : res = kzalloc(sizeof(struct resource), flags);
202 :
203 6 : return res;
204 : }
205 :
206 : /* Return the conflict entry if you can't request it */
207 20 : static struct resource * __request_resource(struct resource *root, struct resource *new)
208 : {
209 20 : resource_size_t start = new->start;
210 20 : resource_size_t end = new->end;
211 : struct resource *tmp, **p;
212 :
213 20 : if (end < start)
214 : return root;
215 20 : if (start < root->start)
216 : return root;
217 20 : if (end > root->end)
218 : return root;
219 20 : p = &root->child;
220 : for (;;) {
221 78 : tmp = *p;
222 78 : if (!tmp || tmp->start > end) {
223 16 : new->sibling = tmp;
224 16 : *p = new;
225 16 : new->parent = root;
226 16 : return NULL;
227 : }
228 62 : p = &tmp->sibling;
229 62 : if (tmp->end < start)
230 58 : continue;
231 : return tmp;
232 58 : }
233 : }
234 :
235 : static int __release_resource(struct resource *old)
236 : {
237 : struct resource *tmp, **p;
238 :
239 0 : p = &old->parent->child;
240 : for (;;) {
241 0 : tmp = *p;
242 0 : if (!tmp)
243 : break;
244 0 : if (tmp == old) {
245 0 : *p = tmp->sibling;
246 0 : old->parent = NULL;
247 : return 0;
248 : }
249 0 : p = &tmp->sibling;
250 : }
251 : return -EINVAL;
252 : }
253 :
254 0 : static void __release_child_resources(struct resource *r)
255 : {
256 0 : struct resource *tmp, *p;
257 : resource_size_t size;
258 :
259 0 : p = r->child;
260 0 : r->child = NULL;
261 0 : while (p) {
262 : tmp = p;
263 0 : p = p->sibling;
264 :
265 0 : tmp->parent = NULL;
266 0 : tmp->sibling = NULL;
267 0 : __release_child_resources(tmp);
268 :
269 0 : printk(KERN_DEBUG "release child resource %pR\n", tmp);
270 : /* need to restore size, and keep flags */
271 : size = resource_size(tmp);
272 0 : tmp->start = 0;
273 0 : tmp->end = size - 1;
274 : }
275 0 : }
276 :
277 0 : void release_child_resources(struct resource *r)
278 : {
279 0 : write_lock(&resource_lock);
280 0 : __release_child_resources(r);
281 0 : write_unlock(&resource_lock);
282 0 : }
283 :
284 : /**
285 : * request_resource_conflict - request and reserve an I/O or memory resource
286 : * @root: root resource descriptor
287 : * @new: resource descriptor desired by caller
288 : *
289 : * Returns 0 for success, conflict resource on error.
290 : */
291 4 : struct resource *request_resource_conflict(struct resource *root, struct resource *new)
292 : {
293 : struct resource *conflict;
294 :
295 4 : write_lock(&resource_lock);
296 4 : conflict = __request_resource(root, new);
297 8 : write_unlock(&resource_lock);
298 4 : return conflict;
299 : }
300 :
301 : /**
302 : * request_resource - request and reserve an I/O or memory resource
303 : * @root: root resource descriptor
304 : * @new: resource descriptor desired by caller
305 : *
306 : * Returns 0 for success, negative error code on error.
307 : */
308 4 : int request_resource(struct resource *root, struct resource *new)
309 : {
310 : struct resource *conflict;
311 :
312 4 : conflict = request_resource_conflict(root, new);
313 4 : return conflict ? -EBUSY : 0;
314 : }
315 :
316 : EXPORT_SYMBOL(request_resource);
317 :
318 : /**
319 : * release_resource - release a previously reserved resource
320 : * @old: resource pointer
321 : */
322 0 : int release_resource(struct resource *old)
323 : {
324 : int retval;
325 :
326 0 : write_lock(&resource_lock);
327 : retval = __release_resource(old);
328 0 : write_unlock(&resource_lock);
329 0 : return retval;
330 : }
331 :
332 : EXPORT_SYMBOL(release_resource);
333 :
334 : /*
335 : * Finds the lowest iomem reosurce exists with-in [res->start.res->end)
336 : * the caller must specify res->start, res->end, res->flags and "name".
337 : * If found, returns 0, res is overwritten, if not found, returns -1.
338 : * This walks through whole tree and not just first level children
339 : * until and unless first_level_children_only is true.
340 : */
341 0 : static int find_next_iomem_res(struct resource *res, char *name,
342 : bool first_level_children_only)
343 : {
344 : resource_size_t start, end;
345 : struct resource *p;
346 : bool sibling_only = false;
347 :
348 : BUG_ON(!res);
349 :
350 0 : start = res->start;
351 0 : end = res->end;
352 : BUG_ON(start >= end);
353 :
354 0 : if (first_level_children_only)
355 : sibling_only = true;
356 :
357 0 : read_lock(&resource_lock);
358 :
359 0 : for (p = iomem_resource.child; p; p = next_resource(p, sibling_only)) {
360 0 : if (p->flags != res->flags)
361 0 : continue;
362 0 : if (name && strcmp(p->name, name))
363 0 : continue;
364 0 : if (p->start > end) {
365 : p = NULL;
366 : break;
367 : }
368 0 : if ((p->end >= start) && (p->start < end))
369 : break;
370 : }
371 :
372 0 : read_unlock(&resource_lock);
373 0 : if (!p)
374 : return -1;
375 : /* copy data */
376 0 : if (res->start < p->start)
377 0 : res->start = p->start;
378 0 : if (res->end > p->end)
379 0 : res->end = p->end;
380 : return 0;
381 : }
382 :
383 : /*
384 : * Walks through iomem resources and calls func() with matching resource
385 : * ranges. This walks through whole tree and not just first level children.
386 : * All the memory ranges which overlap start,end and also match flags and
387 : * name are valid candidates.
388 : *
389 : * @name: name of resource
390 : * @flags: resource flags
391 : * @start: start addr
392 : * @end: end addr
393 : */
394 0 : int walk_iomem_res(char *name, unsigned long flags, u64 start, u64 end,
395 : void *arg, int (*func)(u64, u64, void *))
396 : {
397 : struct resource res;
398 : u64 orig_end;
399 : int ret = -1;
400 :
401 0 : res.start = start;
402 0 : res.end = end;
403 0 : res.flags = flags;
404 : orig_end = res.end;
405 0 : while ((res.start < res.end) &&
406 0 : (!find_next_iomem_res(&res, name, false))) {
407 0 : ret = (*func)(res.start, res.end, arg);
408 0 : if (ret)
409 : break;
410 0 : res.start = res.end + 1;
411 0 : res.end = orig_end;
412 : }
413 0 : return ret;
414 : }
415 :
416 : /*
417 : * This function calls callback against all memory range of "System RAM"
418 : * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY.
419 : * Now, this function is only for "System RAM". This function deals with
420 : * full ranges and not pfn. If resources are not pfn aligned, dealing
421 : * with pfn can truncate ranges.
422 : */
423 0 : int walk_system_ram_res(u64 start, u64 end, void *arg,
424 : int (*func)(u64, u64, void *))
425 : {
426 : struct resource res;
427 : u64 orig_end;
428 : int ret = -1;
429 :
430 0 : res.start = start;
431 0 : res.end = end;
432 0 : res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
433 : orig_end = res.end;
434 0 : while ((res.start < res.end) &&
435 0 : (!find_next_iomem_res(&res, "System RAM", true))) {
436 0 : ret = (*func)(res.start, res.end, arg);
437 0 : if (ret)
438 : break;
439 0 : res.start = res.end + 1;
440 0 : res.end = orig_end;
441 : }
442 0 : return ret;
443 : }
444 :
445 : #if !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
446 :
447 : /*
448 : * This function calls callback against all memory range of "System RAM"
449 : * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY.
450 : * Now, this function is only for "System RAM".
451 : */
452 0 : int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
453 : void *arg, int (*func)(unsigned long, unsigned long, void *))
454 : {
455 : struct resource res;
456 : unsigned long pfn, end_pfn;
457 : u64 orig_end;
458 : int ret = -1;
459 :
460 0 : res.start = (u64) start_pfn << PAGE_SHIFT;
461 0 : res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1;
462 0 : res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
463 : orig_end = res.end;
464 0 : while ((res.start < res.end) &&
465 0 : (find_next_iomem_res(&res, "System RAM", true) >= 0)) {
466 0 : pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT;
467 0 : end_pfn = (res.end + 1) >> PAGE_SHIFT;
468 0 : if (end_pfn > pfn)
469 0 : ret = (*func)(pfn, end_pfn - pfn, arg);
470 0 : if (ret)
471 : break;
472 0 : res.start = res.end + 1;
473 0 : res.end = orig_end;
474 : }
475 0 : return ret;
476 : }
477 :
478 : #endif
479 :
480 0 : static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg)
481 : {
482 0 : return 1;
483 : }
484 : /*
485 : * This generic page_is_ram() returns true if specified address is
486 : * registered as "System RAM" in iomem_resource list.
487 : */
488 0 : int __weak page_is_ram(unsigned long pfn)
489 : {
490 0 : return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1;
491 : }
492 : EXPORT_SYMBOL_GPL(page_is_ram);
493 :
494 : /*
495 : * Search for a resouce entry that fully contains the specified region.
496 : * If found, return 1 if it is RAM, 0 if not.
497 : * If not found, or region is not fully contained, return -1
498 : *
499 : * Used by the ioremap functions to ensure the user is not remapping RAM and is
500 : * a vast speed up over walking through the resource table page by page.
501 : */
502 0 : int region_is_ram(resource_size_t start, unsigned long size)
503 : {
504 : struct resource *p;
505 0 : resource_size_t end = start + size - 1;
506 : int flags = IORESOURCE_MEM | IORESOURCE_BUSY;
507 : const char *name = "System RAM";
508 : int ret = -1;
509 :
510 0 : read_lock(&resource_lock);
511 0 : for (p = iomem_resource.child; p ; p = p->sibling) {
512 0 : if (end < p->start)
513 0 : continue;
514 :
515 0 : if (p->start <= start && end <= p->end) {
516 : /* resource fully contains region */
517 0 : if ((p->flags != flags) || strcmp(p->name, name))
518 : ret = 0;
519 : else
520 : ret = 1;
521 : break;
522 : }
523 0 : if (p->end < start)
524 : break; /* not found */
525 : }
526 0 : read_unlock(&resource_lock);
527 0 : return ret;
528 : }
529 :
530 0 : void __weak arch_remove_reservations(struct resource *avail)
531 : {
532 0 : }
533 :
534 0 : static resource_size_t simple_align_resource(void *data,
535 : const struct resource *avail,
536 : resource_size_t size,
537 : resource_size_t align)
538 : {
539 0 : return avail->start;
540 : }
541 :
542 : static void resource_clip(struct resource *res, resource_size_t min,
543 : resource_size_t max)
544 : {
545 0 : if (res->start < min)
546 0 : res->start = min;
547 0 : if (res->end > max)
548 0 : res->end = max;
549 : }
550 :
551 : /*
552 : * Find empty slot in the resource tree with the given range and
553 : * alignment constraints
554 : */
555 0 : static int __find_resource(struct resource *root, struct resource *old,
556 : struct resource *new,
557 : resource_size_t size,
558 : struct resource_constraint *constraint)
559 : {
560 0 : struct resource *this = root->child;
561 0 : struct resource tmp = *new, avail, alloc;
562 :
563 0 : tmp.start = root->start;
564 : /*
565 : * Skip past an allocated resource that starts at 0, since the assignment
566 : * of this->start - 1 to tmp->end below would cause an underflow.
567 : */
568 0 : if (this && this->start == root->start) {
569 0 : tmp.start = (this == old) ? old->start : this->end + 1;
570 0 : this = this->sibling;
571 : }
572 : for(;;) {
573 0 : if (this)
574 0 : tmp.end = (this == old) ? this->end : this->start - 1;
575 : else
576 0 : tmp.end = root->end;
577 :
578 0 : if (tmp.end < tmp.start)
579 : goto next;
580 :
581 0 : resource_clip(&tmp, constraint->min, constraint->max);
582 0 : arch_remove_reservations(&tmp);
583 :
584 : /* Check for overflow after ALIGN() */
585 0 : avail.start = ALIGN(tmp.start, constraint->align);
586 0 : avail.end = tmp.end;
587 0 : avail.flags = new->flags & ~IORESOURCE_UNSET;
588 0 : if (avail.start >= tmp.start) {
589 : alloc.flags = avail.flags;
590 0 : alloc.start = constraint->alignf(constraint->alignf_data, &avail,
591 : size, constraint->align);
592 0 : alloc.end = alloc.start + size - 1;
593 0 : if (resource_contains(&avail, &alloc)) {
594 0 : new->start = alloc.start;
595 0 : new->end = alloc.end;
596 0 : return 0;
597 : }
598 : }
599 :
600 0 : next: if (!this || this->end == root->end)
601 : break;
602 :
603 0 : if (this != old)
604 0 : tmp.start = this->end + 1;
605 0 : this = this->sibling;
606 0 : }
607 : return -EBUSY;
608 : }
609 :
610 : /*
611 : * Find empty slot in the resource tree given range and alignment.
612 : */
613 : static int find_resource(struct resource *root, struct resource *new,
614 : resource_size_t size,
615 : struct resource_constraint *constraint)
616 : {
617 0 : return __find_resource(root, NULL, new, size, constraint);
618 : }
619 :
620 : /**
621 : * reallocate_resource - allocate a slot in the resource tree given range & alignment.
622 : * The resource will be relocated if the new size cannot be reallocated in the
623 : * current location.
624 : *
625 : * @root: root resource descriptor
626 : * @old: resource descriptor desired by caller
627 : * @newsize: new size of the resource descriptor
628 : * @constraint: the size and alignment constraints to be met.
629 : */
630 0 : static int reallocate_resource(struct resource *root, struct resource *old,
631 : resource_size_t newsize,
632 : struct resource_constraint *constraint)
633 : {
634 : int err=0;
635 0 : struct resource new = *old;
636 : struct resource *conflict;
637 :
638 0 : write_lock(&resource_lock);
639 :
640 0 : if ((err = __find_resource(root, old, &new, newsize, constraint)))
641 : goto out;
642 :
643 0 : if (resource_contains(&new, old)) {
644 0 : old->start = new.start;
645 0 : old->end = new.end;
646 0 : goto out;
647 : }
648 :
649 0 : if (old->child) {
650 : err = -EBUSY;
651 : goto out;
652 : }
653 :
654 0 : if (resource_contains(old, &new)) {
655 0 : old->start = new.start;
656 0 : old->end = new.end;
657 : } else {
658 : __release_resource(old);
659 0 : *old = new;
660 0 : conflict = __request_resource(root, old);
661 : BUG_ON(conflict);
662 : }
663 : out:
664 0 : write_unlock(&resource_lock);
665 0 : return err;
666 : }
667 :
668 :
669 : /**
670 : * allocate_resource - allocate empty slot in the resource tree given range & alignment.
671 : * The resource will be reallocated with a new size if it was already allocated
672 : * @root: root resource descriptor
673 : * @new: resource descriptor desired by caller
674 : * @size: requested resource region size
675 : * @min: minimum boundary to allocate
676 : * @max: maximum boundary to allocate
677 : * @align: alignment requested, in bytes
678 : * @alignf: alignment function, optional, called if not NULL
679 : * @alignf_data: arbitrary data to pass to the @alignf function
680 : */
681 0 : int allocate_resource(struct resource *root, struct resource *new,
682 : resource_size_t size, resource_size_t min,
683 : resource_size_t max, resource_size_t align,
684 : resource_size_t (*alignf)(void *,
685 : const struct resource *,
686 : resource_size_t,
687 : resource_size_t),
688 : void *alignf_data)
689 : {
690 : int err;
691 : struct resource_constraint constraint;
692 :
693 0 : if (!alignf)
694 : alignf = simple_align_resource;
695 :
696 0 : constraint.min = min;
697 0 : constraint.max = max;
698 0 : constraint.align = align;
699 0 : constraint.alignf = alignf;
700 0 : constraint.alignf_data = alignf_data;
701 :
702 0 : if ( new->parent ) {
703 : /* resource is already allocated, try reallocating with
704 : the new constraints */
705 0 : return reallocate_resource(root, new, size, &constraint);
706 : }
707 :
708 0 : write_lock(&resource_lock);
709 : err = find_resource(root, new, size, &constraint);
710 0 : if (err >= 0 && __request_resource(root, new))
711 : err = -EBUSY;
712 0 : write_unlock(&resource_lock);
713 0 : return err;
714 : }
715 :
716 : EXPORT_SYMBOL(allocate_resource);
717 :
718 : /**
719 : * lookup_resource - find an existing resource by a resource start address
720 : * @root: root resource descriptor
721 : * @start: resource start address
722 : *
723 : * Returns a pointer to the resource if found, NULL otherwise
724 : */
725 0 : struct resource *lookup_resource(struct resource *root, resource_size_t start)
726 : {
727 : struct resource *res;
728 :
729 0 : read_lock(&resource_lock);
730 0 : for (res = root->child; res; res = res->sibling) {
731 0 : if (res->start == start)
732 : break;
733 : }
734 0 : read_unlock(&resource_lock);
735 :
736 0 : return res;
737 : }
738 :
739 : /*
740 : * Insert a resource into the resource tree. If successful, return NULL,
741 : * otherwise return the conflicting resource (compare to __request_resource())
742 : */
743 6 : static struct resource * __insert_resource(struct resource *parent, struct resource *new)
744 : {
745 : struct resource *first, *next;
746 :
747 : for (;; parent = first) {
748 6 : first = __request_resource(parent, new);
749 6 : if (!first)
750 : return first;
751 :
752 0 : if (first == parent)
753 : return first;
754 0 : if (WARN_ON(first == new)) /* duplicated insertion */
755 : return first;
756 :
757 0 : if ((first->start > new->start) || (first->end < new->end))
758 : break;
759 0 : if ((first->start == new->start) && (first->end == new->end))
760 : break;
761 : }
762 :
763 : for (next = first; ; next = next->sibling) {
764 : /* Partial overlap? Bad, and unfixable */
765 0 : if (next->start < new->start || next->end > new->end)
766 : return next;
767 0 : if (!next->sibling)
768 : break;
769 0 : if (next->sibling->start > new->end)
770 : break;
771 : }
772 :
773 0 : new->parent = parent;
774 0 : new->sibling = next->sibling;
775 0 : new->child = first;
776 :
777 0 : next->sibling = NULL;
778 0 : for (next = first; next; next = next->sibling)
779 0 : next->parent = new;
780 :
781 0 : if (parent->child == first) {
782 0 : parent->child = new;
783 : } else {
784 : next = parent->child;
785 0 : while (next->sibling != first)
786 : next = next->sibling;
787 0 : next->sibling = new;
788 : }
789 : return NULL;
790 : }
791 :
792 : /**
793 : * insert_resource_conflict - Inserts resource in the resource tree
794 : * @parent: parent of the new resource
795 : * @new: new resource to insert
796 : *
797 : * Returns 0 on success, conflict resource if the resource can't be inserted.
798 : *
799 : * This function is equivalent to request_resource_conflict when no conflict
800 : * happens. If a conflict happens, and the conflicting resources
801 : * entirely fit within the range of the new resource, then the new
802 : * resource is inserted and the conflicting resources become children of
803 : * the new resource.
804 : */
805 6 : struct resource *insert_resource_conflict(struct resource *parent, struct resource *new)
806 : {
807 : struct resource *conflict;
808 :
809 6 : write_lock(&resource_lock);
810 6 : conflict = __insert_resource(parent, new);
811 12 : write_unlock(&resource_lock);
812 6 : return conflict;
813 : }
814 :
815 : /**
816 : * insert_resource - Inserts a resource in the resource tree
817 : * @parent: parent of the new resource
818 : * @new: new resource to insert
819 : *
820 : * Returns 0 on success, -EBUSY if the resource can't be inserted.
821 : */
822 6 : int insert_resource(struct resource *parent, struct resource *new)
823 : {
824 : struct resource *conflict;
825 :
826 6 : conflict = insert_resource_conflict(parent, new);
827 6 : return conflict ? -EBUSY : 0;
828 : }
829 :
830 : /**
831 : * insert_resource_expand_to_fit - Insert a resource into the resource tree
832 : * @root: root resource descriptor
833 : * @new: new resource to insert
834 : *
835 : * Insert a resource into the resource tree, possibly expanding it in order
836 : * to make it encompass any conflicting resources.
837 : */
838 0 : void insert_resource_expand_to_fit(struct resource *root, struct resource *new)
839 : {
840 0 : if (new->parent)
841 0 : return;
842 :
843 0 : write_lock(&resource_lock);
844 : for (;;) {
845 : struct resource *conflict;
846 :
847 0 : conflict = __insert_resource(root, new);
848 0 : if (!conflict)
849 : break;
850 0 : if (conflict == root)
851 : break;
852 :
853 : /* Ok, expand resource to cover the conflict, then try again .. */
854 0 : if (conflict->start < new->start)
855 0 : new->start = conflict->start;
856 0 : if (conflict->end > new->end)
857 0 : new->end = conflict->end;
858 :
859 0 : printk("Expanded resource %s due to conflict with %s\n", new->name, conflict->name);
860 0 : }
861 0 : write_unlock(&resource_lock);
862 : }
863 :
864 0 : static int __adjust_resource(struct resource *res, resource_size_t start,
865 : resource_size_t size)
866 : {
867 0 : struct resource *tmp, *parent = res->parent;
868 0 : resource_size_t end = start + size - 1;
869 : int result = -EBUSY;
870 :
871 0 : if (!parent)
872 : goto skip;
873 :
874 0 : if ((start < parent->start) || (end > parent->end))
875 : goto out;
876 :
877 0 : if (res->sibling && (res->sibling->start <= end))
878 : goto out;
879 :
880 0 : tmp = parent->child;
881 0 : if (tmp != res) {
882 0 : while (tmp->sibling != res)
883 : tmp = tmp->sibling;
884 0 : if (start <= tmp->end)
885 : goto out;
886 : }
887 :
888 : skip:
889 0 : for (tmp = res->child; tmp; tmp = tmp->sibling)
890 0 : if ((tmp->start < start) || (tmp->end > end))
891 : goto out;
892 :
893 0 : res->start = start;
894 0 : res->end = end;
895 : result = 0;
896 :
897 : out:
898 0 : return result;
899 : }
900 :
901 : /**
902 : * adjust_resource - modify a resource's start and size
903 : * @res: resource to modify
904 : * @start: new start value
905 : * @size: new size
906 : *
907 : * Given an existing resource, change its start and size to match the
908 : * arguments. Returns 0 on success, -EBUSY if it can't fit.
909 : * Existing children of the resource are assumed to be immutable.
910 : */
911 0 : int adjust_resource(struct resource *res, resource_size_t start,
912 : resource_size_t size)
913 : {
914 : int result;
915 :
916 0 : write_lock(&resource_lock);
917 0 : result = __adjust_resource(res, start, size);
918 0 : write_unlock(&resource_lock);
919 0 : return result;
920 : }
921 : EXPORT_SYMBOL(adjust_resource);
922 :
923 0 : static void __init __reserve_region_with_split(struct resource *root,
924 : resource_size_t start, resource_size_t end,
925 : const char *name)
926 : {
927 : struct resource *parent = root;
928 : struct resource *conflict;
929 0 : struct resource *res = alloc_resource(GFP_ATOMIC);
930 : struct resource *next_res = NULL;
931 :
932 0 : if (!res)
933 0 : return;
934 :
935 0 : res->name = name;
936 0 : res->start = start;
937 0 : res->end = end;
938 0 : res->flags = IORESOURCE_BUSY;
939 :
940 : while (1) {
941 :
942 0 : conflict = __request_resource(parent, res);
943 0 : if (!conflict) {
944 0 : if (!next_res)
945 : break;
946 : res = next_res;
947 : next_res = NULL;
948 0 : continue;
949 : }
950 :
951 : /* conflict covered whole area */
952 0 : if (conflict->start <= res->start &&
953 0 : conflict->end >= res->end) {
954 0 : free_resource(res);
955 : WARN_ON(next_res);
956 0 : break;
957 : }
958 :
959 : /* failed, split and try again */
960 0 : if (conflict->start > res->start) {
961 0 : end = res->end;
962 0 : res->end = conflict->start - 1;
963 0 : if (conflict->end < end) {
964 0 : next_res = alloc_resource(GFP_ATOMIC);
965 0 : if (!next_res) {
966 0 : free_resource(res);
967 0 : break;
968 : }
969 0 : next_res->name = name;
970 0 : next_res->start = conflict->end + 1;
971 0 : next_res->end = end;
972 0 : next_res->flags = IORESOURCE_BUSY;
973 : }
974 : } else {
975 0 : res->start = conflict->end + 1;
976 : }
977 : }
978 :
979 : }
980 :
981 0 : void __init reserve_region_with_split(struct resource *root,
982 : resource_size_t start, resource_size_t end,
983 : const char *name)
984 : {
985 : int abort = 0;
986 :
987 0 : write_lock(&resource_lock);
988 0 : if (root->start > start || root->end < end) {
989 0 : pr_err("requested range [0x%llx-0x%llx] not in root %pr\n",
990 : (unsigned long long)start, (unsigned long long)end,
991 : root);
992 0 : if (start > root->end || end < root->start)
993 : abort = 1;
994 : else {
995 0 : if (end > root->end)
996 : end = root->end;
997 0 : if (start < root->start)
998 : start = root->start;
999 0 : pr_err("fixing request to [0x%llx-0x%llx]\n",
1000 : (unsigned long long)start,
1001 : (unsigned long long)end);
1002 : }
1003 0 : dump_stack();
1004 : }
1005 0 : if (!abort)
1006 0 : __reserve_region_with_split(root, start, end, name);
1007 0 : write_unlock(&resource_lock);
1008 0 : }
1009 :
1010 : /**
1011 : * resource_alignment - calculate resource's alignment
1012 : * @res: resource pointer
1013 : *
1014 : * Returns alignment on success, 0 (invalid alignment) on failure.
1015 : */
1016 0 : resource_size_t resource_alignment(struct resource *res)
1017 : {
1018 0 : switch (res->flags & (IORESOURCE_SIZEALIGN | IORESOURCE_STARTALIGN)) {
1019 : case IORESOURCE_SIZEALIGN:
1020 0 : return resource_size(res);
1021 : case IORESOURCE_STARTALIGN:
1022 0 : return res->start;
1023 : default:
1024 : return 0;
1025 : }
1026 : }
1027 :
1028 : /*
1029 : * This is compatibility stuff for IO resources.
1030 : *
1031 : * Note how this, unlike the above, knows about
1032 : * the IO flag meanings (busy etc).
1033 : *
1034 : * request_region creates a new busy region.
1035 : *
1036 : * check_region returns non-zero if the area is already busy.
1037 : *
1038 : * release_region releases a matching busy region.
1039 : */
1040 :
1041 : static DECLARE_WAIT_QUEUE_HEAD(muxed_resource_wait);
1042 :
1043 : /**
1044 : * __request_region - create a new busy resource region
1045 : * @parent: parent resource descriptor
1046 : * @start: resource start address
1047 : * @n: resource region size
1048 : * @name: reserving caller's ID string
1049 : * @flags: IO resource flags
1050 : */
1051 12 : struct resource * __request_region(struct resource *parent,
1052 : resource_size_t start, resource_size_t n,
1053 : const char *name, int flags)
1054 : {
1055 12 : DECLARE_WAITQUEUE(wait, current);
1056 6 : struct resource *res = alloc_resource(GFP_KERNEL);
1057 :
1058 6 : if (!res)
1059 : return NULL;
1060 :
1061 6 : res->name = name;
1062 6 : res->start = start;
1063 6 : res->end = start + n - 1;
1064 6 : res->flags = resource_type(parent);
1065 6 : res->flags |= IORESOURCE_BUSY | flags;
1066 :
1067 6 : write_lock(&resource_lock);
1068 :
1069 : for (;;) {
1070 : struct resource *conflict;
1071 :
1072 10 : conflict = __request_resource(parent, res);
1073 10 : if (!conflict)
1074 : break;
1075 4 : if (conflict != parent) {
1076 : parent = conflict;
1077 4 : if (!(conflict->flags & IORESOURCE_BUSY))
1078 4 : continue;
1079 : }
1080 0 : if (conflict->flags & flags & IORESOURCE_MUXED) {
1081 0 : add_wait_queue(&muxed_resource_wait, &wait);
1082 0 : write_unlock(&resource_lock);
1083 0 : set_current_state(TASK_UNINTERRUPTIBLE);
1084 0 : schedule();
1085 0 : remove_wait_queue(&muxed_resource_wait, &wait);
1086 0 : write_lock(&resource_lock);
1087 0 : continue;
1088 : }
1089 : /* Uhhuh, that didn't work out.. */
1090 0 : free_resource(res);
1091 : res = NULL;
1092 0 : break;
1093 : }
1094 12 : write_unlock(&resource_lock);
1095 6 : return res;
1096 : }
1097 : EXPORT_SYMBOL(__request_region);
1098 :
1099 : /**
1100 : * __check_region - check if a resource region is busy or free
1101 : * @parent: parent resource descriptor
1102 : * @start: resource start address
1103 : * @n: resource region size
1104 : *
1105 : * Returns 0 if the region is free at the moment it is checked,
1106 : * returns %-EBUSY if the region is busy.
1107 : *
1108 : * NOTE:
1109 : * This function is deprecated because its use is racy.
1110 : * Even if it returns 0, a subsequent call to request_region()
1111 : * may fail because another driver etc. just allocated the region.
1112 : * Do NOT use it. It will be removed from the kernel.
1113 : */
1114 0 : int __check_region(struct resource *parent, resource_size_t start,
1115 : resource_size_t n)
1116 : {
1117 : struct resource * res;
1118 :
1119 0 : res = __request_region(parent, start, n, "check-region", 0);
1120 0 : if (!res)
1121 : return -EBUSY;
1122 :
1123 0 : release_resource(res);
1124 0 : free_resource(res);
1125 0 : return 0;
1126 : }
1127 : EXPORT_SYMBOL(__check_region);
1128 :
1129 : /**
1130 : * __release_region - release a previously reserved resource region
1131 : * @parent: parent resource descriptor
1132 : * @start: resource start address
1133 : * @n: resource region size
1134 : *
1135 : * The described resource region must match a currently busy region.
1136 : */
1137 0 : void __release_region(struct resource *parent, resource_size_t start,
1138 : resource_size_t n)
1139 : {
1140 : struct resource **p;
1141 : resource_size_t end;
1142 :
1143 0 : p = &parent->child;
1144 0 : end = start + n - 1;
1145 :
1146 0 : write_lock(&resource_lock);
1147 :
1148 : for (;;) {
1149 0 : struct resource *res = *p;
1150 :
1151 0 : if (!res)
1152 : break;
1153 0 : if (res->start <= start && res->end >= end) {
1154 0 : if (!(res->flags & IORESOURCE_BUSY)) {
1155 0 : p = &res->child;
1156 0 : continue;
1157 : }
1158 0 : if (res->start != start || res->end != end)
1159 : break;
1160 0 : *p = res->sibling;
1161 0 : write_unlock(&resource_lock);
1162 0 : if (res->flags & IORESOURCE_MUXED)
1163 0 : wake_up(&muxed_resource_wait);
1164 0 : free_resource(res);
1165 0 : return;
1166 : }
1167 0 : p = &res->sibling;
1168 : }
1169 :
1170 0 : write_unlock(&resource_lock);
1171 :
1172 0 : printk(KERN_WARNING "Trying to free nonexistent resource "
1173 : "<%016llx-%016llx>\n", (unsigned long long)start,
1174 : (unsigned long long)end);
1175 : }
1176 : EXPORT_SYMBOL(__release_region);
1177 :
1178 : #ifdef CONFIG_MEMORY_HOTREMOVE
1179 : /**
1180 : * release_mem_region_adjustable - release a previously reserved memory region
1181 : * @parent: parent resource descriptor
1182 : * @start: resource start address
1183 : * @size: resource region size
1184 : *
1185 : * This interface is intended for memory hot-delete. The requested region
1186 : * is released from a currently busy memory resource. The requested region
1187 : * must either match exactly or fit into a single busy resource entry. In
1188 : * the latter case, the remaining resource is adjusted accordingly.
1189 : * Existing children of the busy memory resource must be immutable in the
1190 : * request.
1191 : *
1192 : * Note:
1193 : * - Additional release conditions, such as overlapping region, can be
1194 : * supported after they are confirmed as valid cases.
1195 : * - When a busy memory resource gets split into two entries, the code
1196 : * assumes that all children remain in the lower address entry for
1197 : * simplicity. Enhance this logic when necessary.
1198 : */
1199 : int release_mem_region_adjustable(struct resource *parent,
1200 : resource_size_t start, resource_size_t size)
1201 : {
1202 : struct resource **p;
1203 : struct resource *res;
1204 : struct resource *new_res;
1205 : resource_size_t end;
1206 : int ret = -EINVAL;
1207 :
1208 : end = start + size - 1;
1209 : if ((start < parent->start) || (end > parent->end))
1210 : return ret;
1211 :
1212 : /* The alloc_resource() result gets checked later */
1213 : new_res = alloc_resource(GFP_KERNEL);
1214 :
1215 : p = &parent->child;
1216 : write_lock(&resource_lock);
1217 :
1218 : while ((res = *p)) {
1219 : if (res->start >= end)
1220 : break;
1221 :
1222 : /* look for the next resource if it does not fit into */
1223 : if (res->start > start || res->end < end) {
1224 : p = &res->sibling;
1225 : continue;
1226 : }
1227 :
1228 : if (!(res->flags & IORESOURCE_MEM))
1229 : break;
1230 :
1231 : if (!(res->flags & IORESOURCE_BUSY)) {
1232 : p = &res->child;
1233 : continue;
1234 : }
1235 :
1236 : /* found the target resource; let's adjust accordingly */
1237 : if (res->start == start && res->end == end) {
1238 : /* free the whole entry */
1239 : *p = res->sibling;
1240 : free_resource(res);
1241 : ret = 0;
1242 : } else if (res->start == start && res->end != end) {
1243 : /* adjust the start */
1244 : ret = __adjust_resource(res, end + 1,
1245 : res->end - end);
1246 : } else if (res->start != start && res->end == end) {
1247 : /* adjust the end */
1248 : ret = __adjust_resource(res, res->start,
1249 : start - res->start);
1250 : } else {
1251 : /* split into two entries */
1252 : if (!new_res) {
1253 : ret = -ENOMEM;
1254 : break;
1255 : }
1256 : new_res->name = res->name;
1257 : new_res->start = end + 1;
1258 : new_res->end = res->end;
1259 : new_res->flags = res->flags;
1260 : new_res->parent = res->parent;
1261 : new_res->sibling = res->sibling;
1262 : new_res->child = NULL;
1263 :
1264 : ret = __adjust_resource(res, res->start,
1265 : start - res->start);
1266 : if (ret)
1267 : break;
1268 : res->sibling = new_res;
1269 : new_res = NULL;
1270 : }
1271 :
1272 : break;
1273 : }
1274 :
1275 : write_unlock(&resource_lock);
1276 : free_resource(new_res);
1277 : return ret;
1278 : }
1279 : #endif /* CONFIG_MEMORY_HOTREMOVE */
1280 :
1281 : /*
1282 : * Managed region resource
1283 : */
1284 0 : static void devm_resource_release(struct device *dev, void *ptr)
1285 : {
1286 : struct resource **r = ptr;
1287 :
1288 0 : release_resource(*r);
1289 0 : }
1290 :
1291 : /**
1292 : * devm_request_resource() - request and reserve an I/O or memory resource
1293 : * @dev: device for which to request the resource
1294 : * @root: root of the resource tree from which to request the resource
1295 : * @new: descriptor of the resource to request
1296 : *
1297 : * This is a device-managed version of request_resource(). There is usually
1298 : * no need to release resources requested by this function explicitly since
1299 : * that will be taken care of when the device is unbound from its driver.
1300 : * If for some reason the resource needs to be released explicitly, because
1301 : * of ordering issues for example, drivers must call devm_release_resource()
1302 : * rather than the regular release_resource().
1303 : *
1304 : * When a conflict is detected between any existing resources and the newly
1305 : * requested resource, an error message will be printed.
1306 : *
1307 : * Returns 0 on success or a negative error code on failure.
1308 : */
1309 0 : int devm_request_resource(struct device *dev, struct resource *root,
1310 : struct resource *new)
1311 : {
1312 : struct resource *conflict, **ptr;
1313 :
1314 0 : ptr = devres_alloc(devm_resource_release, sizeof(*ptr), GFP_KERNEL);
1315 0 : if (!ptr)
1316 : return -ENOMEM;
1317 :
1318 0 : *ptr = new;
1319 :
1320 0 : conflict = request_resource_conflict(root, new);
1321 0 : if (conflict) {
1322 0 : dev_err(dev, "resource collision: %pR conflicts with %s %pR\n",
1323 : new, conflict->name, conflict);
1324 0 : devres_free(ptr);
1325 0 : return -EBUSY;
1326 : }
1327 :
1328 0 : devres_add(dev, ptr);
1329 0 : return 0;
1330 : }
1331 : EXPORT_SYMBOL(devm_request_resource);
1332 :
1333 0 : static int devm_resource_match(struct device *dev, void *res, void *data)
1334 : {
1335 : struct resource **ptr = res;
1336 :
1337 0 : return *ptr == data;
1338 : }
1339 :
1340 : /**
1341 : * devm_release_resource() - release a previously requested resource
1342 : * @dev: device for which to release the resource
1343 : * @new: descriptor of the resource to release
1344 : *
1345 : * Releases a resource previously requested using devm_request_resource().
1346 : */
1347 0 : void devm_release_resource(struct device *dev, struct resource *new)
1348 : {
1349 0 : WARN_ON(devres_release(dev, devm_resource_release, devm_resource_match,
1350 : new));
1351 0 : }
1352 : EXPORT_SYMBOL(devm_release_resource);
1353 :
1354 : struct region_devres {
1355 : struct resource *parent;
1356 : resource_size_t start;
1357 : resource_size_t n;
1358 : };
1359 :
1360 0 : static void devm_region_release(struct device *dev, void *res)
1361 : {
1362 : struct region_devres *this = res;
1363 :
1364 0 : __release_region(this->parent, this->start, this->n);
1365 0 : }
1366 :
1367 0 : static int devm_region_match(struct device *dev, void *res, void *match_data)
1368 : {
1369 : struct region_devres *this = res, *match = match_data;
1370 :
1371 0 : return this->parent == match->parent &&
1372 0 : this->start == match->start && this->n == match->n;
1373 : }
1374 :
1375 2 : struct resource * __devm_request_region(struct device *dev,
1376 : struct resource *parent, resource_size_t start,
1377 : resource_size_t n, const char *name)
1378 : {
1379 : struct region_devres *dr = NULL;
1380 : struct resource *res;
1381 :
1382 2 : dr = devres_alloc(devm_region_release, sizeof(struct region_devres),
1383 : GFP_KERNEL);
1384 2 : if (!dr)
1385 : return NULL;
1386 :
1387 2 : dr->parent = parent;
1388 2 : dr->start = start;
1389 2 : dr->n = n;
1390 :
1391 2 : res = __request_region(parent, start, n, name, 0);
1392 2 : if (res)
1393 2 : devres_add(dev, dr);
1394 : else
1395 0 : devres_free(dr);
1396 :
1397 2 : return res;
1398 : }
1399 : EXPORT_SYMBOL(__devm_request_region);
1400 :
1401 0 : void __devm_release_region(struct device *dev, struct resource *parent,
1402 : resource_size_t start, resource_size_t n)
1403 : {
1404 0 : struct region_devres match_data = { parent, start, n };
1405 :
1406 0 : __release_region(parent, start, n);
1407 0 : WARN_ON(devres_destroy(dev, devm_region_release, devm_region_match,
1408 : &match_data));
1409 0 : }
1410 : EXPORT_SYMBOL(__devm_release_region);
1411 :
1412 : /*
1413 : * Called from init/main.c to reserve IO ports.
1414 : */
1415 : #define MAXRESERVE 4
1416 0 : static int __init reserve_setup(char *str)
1417 : {
1418 : static int reserved;
1419 : static struct resource reserve[MAXRESERVE];
1420 :
1421 : for (;;) {
1422 : unsigned int io_start, io_num;
1423 0 : int x = reserved;
1424 :
1425 0 : if (get_option (&str, &io_start) != 2)
1426 : break;
1427 0 : if (get_option (&str, &io_num) == 0)
1428 : break;
1429 0 : if (x < MAXRESERVE) {
1430 0 : struct resource *res = reserve + x;
1431 0 : res->name = "reserved";
1432 0 : res->start = io_start;
1433 0 : res->end = io_start + io_num - 1;
1434 0 : res->flags = IORESOURCE_BUSY;
1435 0 : res->child = NULL;
1436 0 : if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, res) == 0)
1437 0 : reserved = x+1;
1438 : }
1439 0 : }
1440 0 : return 1;
1441 : }
1442 :
1443 : __setup("reserve=", reserve_setup);
1444 :
1445 : /*
1446 : * Check if the requested addr and size spans more than any slot in the
1447 : * iomem resource tree.
1448 : */
1449 0 : int iomem_map_sanity_check(resource_size_t addr, unsigned long size)
1450 : {
1451 : struct resource *p = &iomem_resource;
1452 : int err = 0;
1453 : loff_t l;
1454 :
1455 0 : read_lock(&resource_lock);
1456 0 : for (p = p->child; p ; p = r_next(NULL, p, &l)) {
1457 : /*
1458 : * We can probably skip the resources without
1459 : * IORESOURCE_IO attribute?
1460 : */
1461 0 : if (p->start >= addr + size)
1462 0 : continue;
1463 0 : if (p->end < addr)
1464 0 : continue;
1465 0 : if (PFN_DOWN(p->start) <= PFN_DOWN(addr) &&
1466 0 : PFN_DOWN(p->end) >= PFN_DOWN(addr + size - 1))
1467 0 : continue;
1468 : /*
1469 : * if a resource is "BUSY", it's not a hardware resource
1470 : * but a driver mapping of such a resource; we don't want
1471 : * to warn for those; some drivers legitimately map only
1472 : * partial hardware resources. (example: vesafb)
1473 : */
1474 0 : if (p->flags & IORESOURCE_BUSY)
1475 0 : continue;
1476 :
1477 0 : printk(KERN_WARNING "resource sanity check: requesting [mem %#010llx-%#010llx], which spans more than %s %pR\n",
1478 : (unsigned long long)addr,
1479 0 : (unsigned long long)(addr + size - 1),
1480 : p->name, p);
1481 : err = -1;
1482 0 : break;
1483 : }
1484 0 : read_unlock(&resource_lock);
1485 :
1486 0 : return err;
1487 : }
1488 :
1489 : #ifdef CONFIG_STRICT_DEVMEM
1490 : static int strict_iomem_checks = 1;
1491 : #else
1492 : static int strict_iomem_checks;
1493 : #endif
1494 :
1495 : /*
1496 : * check if an address is reserved in the iomem resource tree
1497 : * returns 1 if reserved, 0 if not reserved.
1498 : */
1499 0 : int iomem_is_exclusive(u64 addr)
1500 : {
1501 : struct resource *p = &iomem_resource;
1502 : int err = 0;
1503 : loff_t l;
1504 : int size = PAGE_SIZE;
1505 :
1506 0 : if (!strict_iomem_checks)
1507 : return 0;
1508 :
1509 0 : addr = addr & PAGE_MASK;
1510 :
1511 0 : read_lock(&resource_lock);
1512 0 : for (p = p->child; p ; p = r_next(NULL, p, &l)) {
1513 : /*
1514 : * We can probably skip the resources without
1515 : * IORESOURCE_IO attribute?
1516 : */
1517 0 : if (p->start >= addr + size)
1518 : break;
1519 0 : if (p->end < addr)
1520 0 : continue;
1521 0 : if (p->flags & IORESOURCE_BUSY &&
1522 0 : p->flags & IORESOURCE_EXCLUSIVE) {
1523 : err = 1;
1524 : break;
1525 : }
1526 : }
1527 0 : read_unlock(&resource_lock);
1528 :
1529 0 : return err;
1530 : }
1531 :
1532 0 : static int __init strict_iomem(char *str)
1533 : {
1534 0 : if (strstr(str, "relaxed"))
1535 0 : strict_iomem_checks = 0;
1536 0 : if (strstr(str, "strict"))
1537 0 : strict_iomem_checks = 1;
1538 0 : return 1;
1539 : }
1540 :
1541 : __setup("iomem=", strict_iomem);
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