blob: 4337063663efe39f8de666d16c591c84f66db0f7 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
Linus Torvalds1da177e2005-04-16 15:20:36 -070010#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070011#include <linux/errno.h>
12#include <linux/ioport.h>
13#include <linux/init.h>
14#include <linux/slab.h>
15#include <linux/spinlock.h>
16#include <linux/fs.h>
17#include <linux/proc_fs.h>
18#include <linux/seq_file.h>
Tejun Heo9ac78492007-01-20 16:00:26 +090019#include <linux/device.h>
Suresh Siddhad68612b2008-10-28 11:45:42 -070020#include <linux/pfn.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#include <asm/io.h>
22
23
24struct resource ioport_resource = {
25 .name = "PCI IO",
Greg Kroah-Hartman6550e072006-06-12 17:11:31 -070026 .start = 0,
Linus Torvalds1da177e2005-04-16 15:20:36 -070027 .end = IO_SPACE_LIMIT,
28 .flags = IORESOURCE_IO,
29};
Linus Torvalds1da177e2005-04-16 15:20:36 -070030EXPORT_SYMBOL(ioport_resource);
31
32struct resource iomem_resource = {
33 .name = "PCI mem",
Greg Kroah-Hartman6550e072006-06-12 17:11:31 -070034 .start = 0,
35 .end = -1,
Linus Torvalds1da177e2005-04-16 15:20:36 -070036 .flags = IORESOURCE_MEM,
37};
Linus Torvalds1da177e2005-04-16 15:20:36 -070038EXPORT_SYMBOL(iomem_resource);
39
40static DEFINE_RWLOCK(resource_lock);
41
Linus Torvalds1da177e2005-04-16 15:20:36 -070042static void *r_next(struct seq_file *m, void *v, loff_t *pos)
43{
44 struct resource *p = v;
45 (*pos)++;
46 if (p->child)
47 return p->child;
48 while (!p->sibling && p->parent)
49 p = p->parent;
50 return p->sibling;
51}
52
Ingo Molnar13eb8372008-09-26 10:10:12 +020053#ifdef CONFIG_PROC_FS
54
55enum { MAX_IORES_LEVEL = 5 };
56
Linus Torvalds1da177e2005-04-16 15:20:36 -070057static void *r_start(struct seq_file *m, loff_t *pos)
58 __acquires(resource_lock)
59{
60 struct resource *p = m->private;
61 loff_t l = 0;
62 read_lock(&resource_lock);
63 for (p = p->child; p && l < *pos; p = r_next(m, p, &l))
64 ;
65 return p;
66}
67
68static void r_stop(struct seq_file *m, void *v)
69 __releases(resource_lock)
70{
71 read_unlock(&resource_lock);
72}
73
74static int r_show(struct seq_file *m, void *v)
75{
76 struct resource *root = m->private;
77 struct resource *r = v, *p;
78 int width = root->end < 0x10000 ? 4 : 8;
79 int depth;
80
81 for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent)
82 if (p->parent == root)
83 break;
Greg Kroah-Hartman685143ac2006-06-12 15:18:31 -070084 seq_printf(m, "%*s%0*llx-%0*llx : %s\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -070085 depth * 2, "",
Greg Kroah-Hartman685143ac2006-06-12 15:18:31 -070086 width, (unsigned long long) r->start,
87 width, (unsigned long long) r->end,
Linus Torvalds1da177e2005-04-16 15:20:36 -070088 r->name ? r->name : "<BAD>");
89 return 0;
90}
91
Helge Deller15ad7cd2006-12-06 20:40:36 -080092static const struct seq_operations resource_op = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070093 .start = r_start,
94 .next = r_next,
95 .stop = r_stop,
96 .show = r_show,
97};
98
99static int ioports_open(struct inode *inode, struct file *file)
100{
101 int res = seq_open(file, &resource_op);
102 if (!res) {
103 struct seq_file *m = file->private_data;
104 m->private = &ioport_resource;
105 }
106 return res;
107}
108
109static int iomem_open(struct inode *inode, struct file *file)
110{
111 int res = seq_open(file, &resource_op);
112 if (!res) {
113 struct seq_file *m = file->private_data;
114 m->private = &iomem_resource;
115 }
116 return res;
117}
118
Helge Deller15ad7cd2006-12-06 20:40:36 -0800119static const struct file_operations proc_ioports_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120 .open = ioports_open,
121 .read = seq_read,
122 .llseek = seq_lseek,
123 .release = seq_release,
124};
125
Helge Deller15ad7cd2006-12-06 20:40:36 -0800126static const struct file_operations proc_iomem_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127 .open = iomem_open,
128 .read = seq_read,
129 .llseek = seq_lseek,
130 .release = seq_release,
131};
132
133static int __init ioresources_init(void)
134{
Denis V. Lunevc33fff02008-04-29 01:02:31 -0700135 proc_create("ioports", 0, NULL, &proc_ioports_operations);
136 proc_create("iomem", 0, NULL, &proc_iomem_operations);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137 return 0;
138}
139__initcall(ioresources_init);
140
141#endif /* CONFIG_PROC_FS */
142
143/* Return the conflict entry if you can't request it */
144static struct resource * __request_resource(struct resource *root, struct resource *new)
145{
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700146 resource_size_t start = new->start;
147 resource_size_t end = new->end;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148 struct resource *tmp, **p;
149
150 if (end < start)
151 return root;
152 if (start < root->start)
153 return root;
154 if (end > root->end)
155 return root;
156 p = &root->child;
157 for (;;) {
158 tmp = *p;
159 if (!tmp || tmp->start > end) {
160 new->sibling = tmp;
161 *p = new;
162 new->parent = root;
163 return NULL;
164 }
165 p = &tmp->sibling;
166 if (tmp->end < start)
167 continue;
168 return tmp;
169 }
170}
171
172static int __release_resource(struct resource *old)
173{
174 struct resource *tmp, **p;
175
176 p = &old->parent->child;
177 for (;;) {
178 tmp = *p;
179 if (!tmp)
180 break;
181 if (tmp == old) {
182 *p = tmp->sibling;
183 old->parent = NULL;
184 return 0;
185 }
186 p = &tmp->sibling;
187 }
188 return -EINVAL;
189}
190
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700191/**
192 * request_resource - request and reserve an I/O or memory resource
193 * @root: root resource descriptor
194 * @new: resource descriptor desired by caller
195 *
196 * Returns 0 for success, negative error code on error.
197 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198int request_resource(struct resource *root, struct resource *new)
199{
200 struct resource *conflict;
201
202 write_lock(&resource_lock);
203 conflict = __request_resource(root, new);
204 write_unlock(&resource_lock);
205 return conflict ? -EBUSY : 0;
206}
207
208EXPORT_SYMBOL(request_resource);
209
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700210/**
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700211 * release_resource - release a previously reserved resource
212 * @old: resource pointer
213 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214int release_resource(struct resource *old)
215{
216 int retval;
217
218 write_lock(&resource_lock);
219 retval = __release_resource(old);
220 write_unlock(&resource_lock);
221 return retval;
222}
223
224EXPORT_SYMBOL(release_resource);
225
Badari Pulavartya99824f2008-02-05 00:10:18 -0800226#if defined(CONFIG_MEMORY_HOTPLUG) && !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700227/*
228 * Finds the lowest memory reosurce exists within [res->start.res->end)
229 * the caller must specify res->start, res->end, res->flags.
230 * If found, returns 0, res is overwritten, if not found, returns -1.
231 */
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700232static int find_next_system_ram(struct resource *res)
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700233{
234 resource_size_t start, end;
235 struct resource *p;
236
237 BUG_ON(!res);
238
239 start = res->start;
240 end = res->end;
KAMEZAWA Hiroyuki58c1b5b2006-08-05 12:15:01 -0700241 BUG_ON(start >= end);
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700242
243 read_lock(&resource_lock);
244 for (p = iomem_resource.child; p ; p = p->sibling) {
245 /* system ram is just marked as IORESOURCE_MEM */
246 if (p->flags != res->flags)
247 continue;
248 if (p->start > end) {
249 p = NULL;
250 break;
251 }
KAMEZAWA Hiroyuki58c1b5b2006-08-05 12:15:01 -0700252 if ((p->end >= start) && (p->start < end))
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700253 break;
254 }
255 read_unlock(&resource_lock);
256 if (!p)
257 return -1;
258 /* copy data */
KAMEZAWA Hiroyuki0f04ab52006-08-05 12:14:59 -0700259 if (res->start < p->start)
260 res->start = p->start;
261 if (res->end > p->end)
262 res->end = p->end;
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700263 return 0;
264}
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700265int
266walk_memory_resource(unsigned long start_pfn, unsigned long nr_pages, void *arg,
267 int (*func)(unsigned long, unsigned long, void *))
268{
269 struct resource res;
270 unsigned long pfn, len;
271 u64 orig_end;
272 int ret = -1;
273 res.start = (u64) start_pfn << PAGE_SHIFT;
274 res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1;
Yasunori Goto887c3cb2007-11-14 16:59:20 -0800275 res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700276 orig_end = res.end;
277 while ((res.start < res.end) && (find_next_system_ram(&res) >= 0)) {
278 pfn = (unsigned long)(res.start >> PAGE_SHIFT);
279 len = (unsigned long)((res.end + 1 - res.start) >> PAGE_SHIFT);
280 ret = (*func)(pfn, len, arg);
281 if (ret)
282 break;
283 res.start = res.end + 1;
284 res.end = orig_end;
285 }
286 return ret;
287}
288
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700289#endif
290
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291/*
292 * Find empty slot in the resource tree given range and alignment.
293 */
294static int find_resource(struct resource *root, struct resource *new,
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700295 resource_size_t size, resource_size_t min,
296 resource_size_t max, resource_size_t align,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297 void (*alignf)(void *, struct resource *,
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700298 resource_size_t, resource_size_t),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299 void *alignf_data)
300{
301 struct resource *this = root->child;
302
303 new->start = root->start;
304 /*
305 * Skip past an allocated resource that starts at 0, since the assignment
306 * of this->start - 1 to new->end below would cause an underflow.
307 */
308 if (this && this->start == 0) {
309 new->start = this->end + 1;
310 this = this->sibling;
311 }
312 for(;;) {
313 if (this)
314 new->end = this->start - 1;
315 else
316 new->end = root->end;
317 if (new->start < min)
318 new->start = min;
319 if (new->end > max)
320 new->end = max;
Nick Wilson8c0e33c2005-06-25 14:59:00 -0700321 new->start = ALIGN(new->start, align);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322 if (alignf)
323 alignf(alignf_data, new, size, align);
Lennert Buytenhekb52402c2005-04-16 15:25:58 -0700324 if (new->start < new->end && new->end - new->start >= size - 1) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325 new->end = new->start + size - 1;
326 return 0;
327 }
328 if (!this)
329 break;
330 new->start = this->end + 1;
331 this = this->sibling;
332 }
333 return -EBUSY;
334}
335
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700336/**
337 * allocate_resource - allocate empty slot in the resource tree given range & alignment
338 * @root: root resource descriptor
339 * @new: resource descriptor desired by caller
340 * @size: requested resource region size
341 * @min: minimum size to allocate
342 * @max: maximum size to allocate
343 * @align: alignment requested, in bytes
344 * @alignf: alignment function, optional, called if not NULL
345 * @alignf_data: arbitrary data to pass to the @alignf function
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346 */
347int allocate_resource(struct resource *root, struct resource *new,
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700348 resource_size_t size, resource_size_t min,
349 resource_size_t max, resource_size_t align,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 void (*alignf)(void *, struct resource *,
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700351 resource_size_t, resource_size_t),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352 void *alignf_data)
353{
354 int err;
355
356 write_lock(&resource_lock);
357 err = find_resource(root, new, size, min, max, align, alignf, alignf_data);
358 if (err >= 0 && __request_resource(root, new))
359 err = -EBUSY;
360 write_unlock(&resource_lock);
361 return err;
362}
363
364EXPORT_SYMBOL(allocate_resource);
365
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700366/*
367 * Insert a resource into the resource tree. If successful, return NULL,
368 * otherwise return the conflicting resource (compare to __request_resource())
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369 */
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700370static struct resource * __insert_resource(struct resource *parent, struct resource *new)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372 struct resource *first, *next;
373
Matthew Wilcoxd33b6fb2006-06-30 02:31:24 -0700374 for (;; parent = first) {
Matthew Wilcoxd33b6fb2006-06-30 02:31:24 -0700375 first = __request_resource(parent, new);
376 if (!first)
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700377 return first;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378
Matthew Wilcoxd33b6fb2006-06-30 02:31:24 -0700379 if (first == parent)
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700380 return first;
Matthew Wilcoxd33b6fb2006-06-30 02:31:24 -0700381
382 if ((first->start > new->start) || (first->end < new->end))
383 break;
384 if ((first->start == new->start) && (first->end == new->end))
385 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386 }
387
388 for (next = first; ; next = next->sibling) {
389 /* Partial overlap? Bad, and unfixable */
390 if (next->start < new->start || next->end > new->end)
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700391 return next;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392 if (!next->sibling)
393 break;
394 if (next->sibling->start > new->end)
395 break;
396 }
397
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398 new->parent = parent;
399 new->sibling = next->sibling;
400 new->child = first;
401
402 next->sibling = NULL;
403 for (next = first; next; next = next->sibling)
404 next->parent = new;
405
406 if (parent->child == first) {
407 parent->child = new;
408 } else {
409 next = parent->child;
410 while (next->sibling != first)
411 next = next->sibling;
412 next->sibling = new;
413 }
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700414 return NULL;
415}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700417/**
418 * insert_resource - Inserts a resource in the resource tree
419 * @parent: parent of the new resource
420 * @new: new resource to insert
421 *
422 * Returns 0 on success, -EBUSY if the resource can't be inserted.
423 *
424 * This function is equivalent to request_resource when no conflict
425 * happens. If a conflict happens, and the conflicting resources
426 * entirely fit within the range of the new resource, then the new
427 * resource is inserted and the conflicting resources become children of
428 * the new resource.
429 */
430int insert_resource(struct resource *parent, struct resource *new)
431{
432 struct resource *conflict;
433
434 write_lock(&resource_lock);
435 conflict = __insert_resource(parent, new);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436 write_unlock(&resource_lock);
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700437 return conflict ? -EBUSY : 0;
438}
439
440/**
441 * insert_resource_expand_to_fit - Insert a resource into the resource tree
Randy Dunlap6781f4a2008-08-31 20:31:55 -0700442 * @root: root resource descriptor
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700443 * @new: new resource to insert
444 *
445 * Insert a resource into the resource tree, possibly expanding it in order
446 * to make it encompass any conflicting resources.
447 */
448void insert_resource_expand_to_fit(struct resource *root, struct resource *new)
449{
450 if (new->parent)
451 return;
452
453 write_lock(&resource_lock);
454 for (;;) {
455 struct resource *conflict;
456
457 conflict = __insert_resource(root, new);
458 if (!conflict)
459 break;
460 if (conflict == root)
461 break;
462
463 /* Ok, expand resource to cover the conflict, then try again .. */
464 if (conflict->start < new->start)
465 new->start = conflict->start;
466 if (conflict->end > new->end)
467 new->end = conflict->end;
468
469 printk("Expanded resource %s due to conflict with %s\n", new->name, conflict->name);
470 }
471 write_unlock(&resource_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472}
473
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700474/**
475 * adjust_resource - modify a resource's start and size
476 * @res: resource to modify
477 * @start: new start value
478 * @size: new size
479 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700480 * Given an existing resource, change its start and size to match the
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700481 * arguments. Returns 0 on success, -EBUSY if it can't fit.
482 * Existing children of the resource are assumed to be immutable.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483 */
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700484int adjust_resource(struct resource *res, resource_size_t start, resource_size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485{
486 struct resource *tmp, *parent = res->parent;
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700487 resource_size_t end = start + size - 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700488 int result = -EBUSY;
489
490 write_lock(&resource_lock);
491
492 if ((start < parent->start) || (end > parent->end))
493 goto out;
494
495 for (tmp = res->child; tmp; tmp = tmp->sibling) {
496 if ((tmp->start < start) || (tmp->end > end))
497 goto out;
498 }
499
500 if (res->sibling && (res->sibling->start <= end))
501 goto out;
502
503 tmp = parent->child;
504 if (tmp != res) {
505 while (tmp->sibling != res)
506 tmp = tmp->sibling;
507 if (start <= tmp->end)
508 goto out;
509 }
510
511 res->start = start;
512 res->end = end;
513 result = 0;
514
515 out:
516 write_unlock(&resource_lock);
517 return result;
518}
519
Yinghai Lu268364a2008-09-04 21:02:44 +0200520static void __init __reserve_region_with_split(struct resource *root,
521 resource_size_t start, resource_size_t end,
522 const char *name)
523{
524 struct resource *parent = root;
525 struct resource *conflict;
Linus Torvalds42c02022008-11-01 09:53:58 -0700526 struct resource *res = kzalloc(sizeof(*res), GFP_ATOMIC);
Yinghai Lu268364a2008-09-04 21:02:44 +0200527
528 if (!res)
529 return;
530
531 res->name = name;
532 res->start = start;
533 res->end = end;
534 res->flags = IORESOURCE_BUSY;
535
536 for (;;) {
537 conflict = __request_resource(parent, res);
538 if (!conflict)
539 break;
540 if (conflict != parent) {
541 parent = conflict;
542 if (!(conflict->flags & IORESOURCE_BUSY))
543 continue;
544 }
545
546 /* Uhhuh, that didn't work out.. */
547 kfree(res);
548 res = NULL;
549 break;
550 }
551
552 if (!res) {
Yinghai Lu268364a2008-09-04 21:02:44 +0200553 /* failed, split and try again */
554
Ingo Molnar1cf44ba2008-09-04 21:26:06 +0200555 /* conflict covered whole area */
Yinghai Lu268364a2008-09-04 21:02:44 +0200556 if (conflict->start <= start && conflict->end >= end)
557 return;
558
559 if (conflict->start > start)
560 __reserve_region_with_split(root, start, conflict->start-1, name);
561 if (!(conflict->flags & IORESOURCE_BUSY)) {
562 resource_size_t common_start, common_end;
563
564 common_start = max(conflict->start, start);
565 common_end = min(conflict->end, end);
566 if (common_start < common_end)
567 __reserve_region_with_split(root, common_start, common_end, name);
568 }
569 if (conflict->end < end)
570 __reserve_region_with_split(root, conflict->end+1, end, name);
571 }
572
573}
574
Paul Mundtbea92112008-10-22 19:31:11 +0900575void __init reserve_region_with_split(struct resource *root,
Yinghai Lu268364a2008-09-04 21:02:44 +0200576 resource_size_t start, resource_size_t end,
577 const char *name)
578{
579 write_lock(&resource_lock);
580 __reserve_region_with_split(root, start, end, name);
581 write_unlock(&resource_lock);
582}
583
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584EXPORT_SYMBOL(adjust_resource);
585
Ivan Kokshaysky88452562008-03-30 19:50:14 +0400586/**
587 * resource_alignment - calculate resource's alignment
588 * @res: resource pointer
589 *
590 * Returns alignment on success, 0 (invalid alignment) on failure.
591 */
592resource_size_t resource_alignment(struct resource *res)
593{
594 switch (res->flags & (IORESOURCE_SIZEALIGN | IORESOURCE_STARTALIGN)) {
595 case IORESOURCE_SIZEALIGN:
Magnus Damm1a4e5642008-07-29 22:32:57 -0700596 return resource_size(res);
Ivan Kokshaysky88452562008-03-30 19:50:14 +0400597 case IORESOURCE_STARTALIGN:
598 return res->start;
599 default:
600 return 0;
601 }
602}
603
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604/*
605 * This is compatibility stuff for IO resources.
606 *
607 * Note how this, unlike the above, knows about
608 * the IO flag meanings (busy etc).
609 *
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700610 * request_region creates a new busy region.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611 *
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700612 * check_region returns non-zero if the area is already busy.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 *
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700614 * release_region releases a matching busy region.
615 */
616
617/**
618 * __request_region - create a new busy resource region
619 * @parent: parent resource descriptor
620 * @start: resource start address
621 * @n: resource region size
622 * @name: reserving caller's ID string
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623 */
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700624struct resource * __request_region(struct resource *parent,
625 resource_size_t start, resource_size_t n,
626 const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627{
Pekka J Enbergdd392712005-09-06 15:18:31 -0700628 struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700630 if (!res)
631 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700633 res->name = name;
634 res->start = start;
635 res->end = start + n - 1;
636 res->flags = IORESOURCE_BUSY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700638 write_lock(&resource_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700640 for (;;) {
641 struct resource *conflict;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700643 conflict = __request_resource(parent, res);
644 if (!conflict)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645 break;
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700646 if (conflict != parent) {
647 parent = conflict;
648 if (!(conflict->flags & IORESOURCE_BUSY))
649 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650 }
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700651
652 /* Uhhuh, that didn't work out.. */
653 kfree(res);
654 res = NULL;
655 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700656 }
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700657 write_unlock(&resource_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658 return res;
659}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660EXPORT_SYMBOL(__request_region);
661
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700662/**
663 * __check_region - check if a resource region is busy or free
664 * @parent: parent resource descriptor
665 * @start: resource start address
666 * @n: resource region size
667 *
668 * Returns 0 if the region is free at the moment it is checked,
669 * returns %-EBUSY if the region is busy.
670 *
671 * NOTE:
672 * This function is deprecated because its use is racy.
673 * Even if it returns 0, a subsequent call to request_region()
674 * may fail because another driver etc. just allocated the region.
675 * Do NOT use it. It will be removed from the kernel.
676 */
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700677int __check_region(struct resource *parent, resource_size_t start,
678 resource_size_t n)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700679{
680 struct resource * res;
681
682 res = __request_region(parent, start, n, "check-region");
683 if (!res)
684 return -EBUSY;
685
686 release_resource(res);
687 kfree(res);
688 return 0;
689}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700690EXPORT_SYMBOL(__check_region);
691
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700692/**
693 * __release_region - release a previously reserved resource region
694 * @parent: parent resource descriptor
695 * @start: resource start address
696 * @n: resource region size
697 *
698 * The described resource region must match a currently busy region.
699 */
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700700void __release_region(struct resource *parent, resource_size_t start,
701 resource_size_t n)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700702{
703 struct resource **p;
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700704 resource_size_t end;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705
706 p = &parent->child;
707 end = start + n - 1;
708
709 write_lock(&resource_lock);
710
711 for (;;) {
712 struct resource *res = *p;
713
714 if (!res)
715 break;
716 if (res->start <= start && res->end >= end) {
717 if (!(res->flags & IORESOURCE_BUSY)) {
718 p = &res->child;
719 continue;
720 }
721 if (res->start != start || res->end != end)
722 break;
723 *p = res->sibling;
724 write_unlock(&resource_lock);
725 kfree(res);
726 return;
727 }
728 p = &res->sibling;
729 }
730
731 write_unlock(&resource_lock);
732
Greg Kroah-Hartman685143ac2006-06-12 15:18:31 -0700733 printk(KERN_WARNING "Trying to free nonexistent resource "
734 "<%016llx-%016llx>\n", (unsigned long long)start,
735 (unsigned long long)end);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700736}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737EXPORT_SYMBOL(__release_region);
738
739/*
Tejun Heo9ac78492007-01-20 16:00:26 +0900740 * Managed region resource
741 */
742struct region_devres {
743 struct resource *parent;
744 resource_size_t start;
745 resource_size_t n;
746};
747
748static void devm_region_release(struct device *dev, void *res)
749{
750 struct region_devres *this = res;
751
752 __release_region(this->parent, this->start, this->n);
753}
754
755static int devm_region_match(struct device *dev, void *res, void *match_data)
756{
757 struct region_devres *this = res, *match = match_data;
758
759 return this->parent == match->parent &&
760 this->start == match->start && this->n == match->n;
761}
762
763struct resource * __devm_request_region(struct device *dev,
764 struct resource *parent, resource_size_t start,
765 resource_size_t n, const char *name)
766{
767 struct region_devres *dr = NULL;
768 struct resource *res;
769
770 dr = devres_alloc(devm_region_release, sizeof(struct region_devres),
771 GFP_KERNEL);
772 if (!dr)
773 return NULL;
774
775 dr->parent = parent;
776 dr->start = start;
777 dr->n = n;
778
779 res = __request_region(parent, start, n, name);
780 if (res)
781 devres_add(dev, dr);
782 else
783 devres_free(dr);
784
785 return res;
786}
787EXPORT_SYMBOL(__devm_request_region);
788
789void __devm_release_region(struct device *dev, struct resource *parent,
790 resource_size_t start, resource_size_t n)
791{
792 struct region_devres match_data = { parent, start, n };
793
794 __release_region(parent, start, n);
795 WARN_ON(devres_destroy(dev, devm_region_release, devm_region_match,
796 &match_data));
797}
798EXPORT_SYMBOL(__devm_release_region);
799
800/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700801 * Called from init/main.c to reserve IO ports.
802 */
803#define MAXRESERVE 4
804static int __init reserve_setup(char *str)
805{
806 static int reserved;
807 static struct resource reserve[MAXRESERVE];
808
809 for (;;) {
810 int io_start, io_num;
811 int x = reserved;
812
813 if (get_option (&str, &io_start) != 2)
814 break;
815 if (get_option (&str, &io_num) == 0)
816 break;
817 if (x < MAXRESERVE) {
818 struct resource *res = reserve + x;
819 res->name = "reserved";
820 res->start = io_start;
821 res->end = io_start + io_num - 1;
822 res->flags = IORESOURCE_BUSY;
823 res->child = NULL;
824 if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, res) == 0)
825 reserved = x+1;
826 }
827 }
828 return 1;
829}
830
831__setup("reserve=", reserve_setup);
Suresh Siddha379daf62008-09-25 18:43:34 -0700832
833/*
834 * Check if the requested addr and size spans more than any slot in the
835 * iomem resource tree.
836 */
837int iomem_map_sanity_check(resource_size_t addr, unsigned long size)
838{
839 struct resource *p = &iomem_resource;
840 int err = 0;
841 loff_t l;
842
843 read_lock(&resource_lock);
844 for (p = p->child; p ; p = r_next(NULL, p, &l)) {
845 /*
846 * We can probably skip the resources without
847 * IORESOURCE_IO attribute?
848 */
849 if (p->start >= addr + size)
850 continue;
851 if (p->end < addr)
852 continue;
Suresh Siddhad68612b2008-10-28 11:45:42 -0700853 if (PFN_DOWN(p->start) <= PFN_DOWN(addr) &&
854 PFN_DOWN(p->end) >= PFN_DOWN(addr + size - 1))
Suresh Siddha379daf62008-09-25 18:43:34 -0700855 continue;
856 printk(KERN_WARNING "resource map sanity check conflict: "
857 "0x%llx 0x%llx 0x%llx 0x%llx %s\n",
Ingo Molnar13eb8372008-09-26 10:10:12 +0200858 (unsigned long long)addr,
859 (unsigned long long)(addr + size - 1),
860 (unsigned long long)p->start,
861 (unsigned long long)p->end,
862 p->name);
Suresh Siddha379daf62008-09-25 18:43:34 -0700863 err = -1;
864 break;
865 }
866 read_unlock(&resource_lock);
867
868 return err;
869}