Commit | Line | Data |
---|---|---|
1da177e4 LT |
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 | ||
1da177e4 | 10 | #include <linux/module.h> |
1da177e4 LT |
11 | #include <linux/errno.h> |
12 | #include <linux/ioport.h> | |
13 | #include <linux/init.h> | |
14 | #include <linux/slab.h> | |
15 | #include <linux/spinlock.h> | |
16 | #include <linux/fs.h> | |
17 | #include <linux/proc_fs.h> | |
18 | #include <linux/seq_file.h> | |
9ac7849e | 19 | #include <linux/device.h> |
d68612b2 | 20 | #include <linux/pfn.h> |
1da177e4 LT |
21 | #include <asm/io.h> |
22 | ||
23 | ||
24 | struct resource ioport_resource = { | |
25 | .name = "PCI IO", | |
6550e07f | 26 | .start = 0, |
1da177e4 LT |
27 | .end = IO_SPACE_LIMIT, |
28 | .flags = IORESOURCE_IO, | |
29 | }; | |
1da177e4 LT |
30 | EXPORT_SYMBOL(ioport_resource); |
31 | ||
32 | struct resource iomem_resource = { | |
33 | .name = "PCI mem", | |
6550e07f GKH |
34 | .start = 0, |
35 | .end = -1, | |
1da177e4 LT |
36 | .flags = IORESOURCE_MEM, |
37 | }; | |
1da177e4 LT |
38 | EXPORT_SYMBOL(iomem_resource); |
39 | ||
40 | static DEFINE_RWLOCK(resource_lock); | |
41 | ||
1da177e4 LT |
42 | static 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 | ||
13eb8375 IM |
53 | #ifdef CONFIG_PROC_FS |
54 | ||
55 | enum { MAX_IORES_LEVEL = 5 }; | |
56 | ||
1da177e4 LT |
57 | static 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 | ||
68 | static void r_stop(struct seq_file *m, void *v) | |
69 | __releases(resource_lock) | |
70 | { | |
71 | read_unlock(&resource_lock); | |
72 | } | |
73 | ||
74 | static 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; | |
685143ac | 84 | seq_printf(m, "%*s%0*llx-%0*llx : %s\n", |
1da177e4 | 85 | depth * 2, "", |
685143ac GKH |
86 | width, (unsigned long long) r->start, |
87 | width, (unsigned long long) r->end, | |
1da177e4 LT |
88 | r->name ? r->name : "<BAD>"); |
89 | return 0; | |
90 | } | |
91 | ||
15ad7cdc | 92 | static const struct seq_operations resource_op = { |
1da177e4 LT |
93 | .start = r_start, |
94 | .next = r_next, | |
95 | .stop = r_stop, | |
96 | .show = r_show, | |
97 | }; | |
98 | ||
99 | static 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 | ||
109 | static 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 | ||
15ad7cdc | 119 | static const struct file_operations proc_ioports_operations = { |
1da177e4 LT |
120 | .open = ioports_open, |
121 | .read = seq_read, | |
122 | .llseek = seq_lseek, | |
123 | .release = seq_release, | |
124 | }; | |
125 | ||
15ad7cdc | 126 | static const struct file_operations proc_iomem_operations = { |
1da177e4 LT |
127 | .open = iomem_open, |
128 | .read = seq_read, | |
129 | .llseek = seq_lseek, | |
130 | .release = seq_release, | |
131 | }; | |
132 | ||
133 | static int __init ioresources_init(void) | |
134 | { | |
c33fff0a DL |
135 | proc_create("ioports", 0, NULL, &proc_ioports_operations); |
136 | proc_create("iomem", 0, NULL, &proc_iomem_operations); | |
1da177e4 LT |
137 | 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 */ | |
144 | static struct resource * __request_resource(struct resource *root, struct resource *new) | |
145 | { | |
d75fc8bb GKH |
146 | resource_size_t start = new->start; |
147 | resource_size_t end = new->end; | |
1da177e4 LT |
148 | 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 | ||
172 | static 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 | ||
e1ca66d1 RD |
191 | /** |
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 | */ | |
1da177e4 LT |
198 | int 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 | ||
208 | EXPORT_SYMBOL(request_resource); | |
209 | ||
e1ca66d1 RD |
210 | /** |
211 | * release_resource - release a previously reserved resource | |
212 | * @old: resource pointer | |
213 | */ | |
1da177e4 LT |
214 | int 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 | ||
224 | EXPORT_SYMBOL(release_resource); | |
225 | ||
a99824f3 | 226 | #if defined(CONFIG_MEMORY_HOTPLUG) && !defined(CONFIG_ARCH_HAS_WALK_MEMORY) |
2842f114 KH |
227 | /* |
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 | */ | |
75884fb1 | 232 | static int find_next_system_ram(struct resource *res) |
2842f114 KH |
233 | { |
234 | resource_size_t start, end; | |
235 | struct resource *p; | |
236 | ||
237 | BUG_ON(!res); | |
238 | ||
239 | start = res->start; | |
240 | end = res->end; | |
58c1b5b0 | 241 | BUG_ON(start >= end); |
2842f114 KH |
242 | |
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 | } | |
58c1b5b0 | 252 | if ((p->end >= start) && (p->start < end)) |
2842f114 KH |
253 | break; |
254 | } | |
255 | read_unlock(&resource_lock); | |
256 | if (!p) | |
257 | return -1; | |
258 | /* copy data */ | |
0f04ab5e KH |
259 | if (res->start < p->start) |
260 | res->start = p->start; | |
261 | if (res->end > p->end) | |
262 | res->end = p->end; | |
2842f114 KH |
263 | return 0; |
264 | } | |
75884fb1 KH |
265 | int |
266 | walk_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; | |
887c3cb1 | 275 | res.flags = IORESOURCE_MEM | IORESOURCE_BUSY; |
75884fb1 KH |
276 | 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 | ||
2842f114 KH |
289 | #endif |
290 | ||
1da177e4 LT |
291 | /* |
292 | * Find empty slot in the resource tree given range and alignment. | |
293 | */ | |
294 | static int find_resource(struct resource *root, struct resource *new, | |
d75fc8bb GKH |
295 | resource_size_t size, resource_size_t min, |
296 | resource_size_t max, resource_size_t align, | |
1da177e4 | 297 | void (*alignf)(void *, struct resource *, |
d75fc8bb | 298 | resource_size_t, resource_size_t), |
1da177e4 LT |
299 | 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; | |
8c0e33c1 | 321 | new->start = ALIGN(new->start, align); |
1da177e4 LT |
322 | if (alignf) |
323 | alignf(alignf_data, new, size, align); | |
b52402c7 | 324 | if (new->start < new->end && new->end - new->start >= size - 1) { |
1da177e4 LT |
325 | 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 | ||
e1ca66d1 RD |
336 | /** |
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 | |
1da177e4 LT |
346 | */ |
347 | int allocate_resource(struct resource *root, struct resource *new, | |
d75fc8bb GKH |
348 | resource_size_t size, resource_size_t min, |
349 | resource_size_t max, resource_size_t align, | |
1da177e4 | 350 | void (*alignf)(void *, struct resource *, |
d75fc8bb | 351 | resource_size_t, resource_size_t), |
1da177e4 LT |
352 | 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 | ||
364 | EXPORT_SYMBOL(allocate_resource); | |
365 | ||
bef69ea0 LT |
366 | /* |
367 | * Insert a resource into the resource tree. If successful, return NULL, | |
368 | * otherwise return the conflicting resource (compare to __request_resource()) | |
1da177e4 | 369 | */ |
bef69ea0 | 370 | static struct resource * __insert_resource(struct resource *parent, struct resource *new) |
1da177e4 | 371 | { |
1da177e4 LT |
372 | struct resource *first, *next; |
373 | ||
d33b6fba | 374 | for (;; parent = first) { |
d33b6fba MW |
375 | first = __request_resource(parent, new); |
376 | if (!first) | |
bef69ea0 | 377 | return first; |
d33b6fba | 378 | |
d33b6fba | 379 | if (first == parent) |
bef69ea0 | 380 | return first; |
d33b6fba MW |
381 | |
382 | if ((first->start > new->start) || (first->end < new->end)) | |
383 | break; | |
384 | if ((first->start == new->start) && (first->end == new->end)) | |
385 | break; | |
1da177e4 LT |
386 | } |
387 | ||
388 | for (next = first; ; next = next->sibling) { | |
389 | /* Partial overlap? Bad, and unfixable */ | |
390 | if (next->start < new->start || next->end > new->end) | |
bef69ea0 | 391 | return next; |
1da177e4 LT |
392 | if (!next->sibling) |
393 | break; | |
394 | if (next->sibling->start > new->end) | |
395 | break; | |
396 | } | |
397 | ||
1da177e4 LT |
398 | 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 | } | |
bef69ea0 LT |
414 | return NULL; |
415 | } | |
1da177e4 | 416 | |
bef69ea0 LT |
417 | /** |
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 | */ | |
430 | int 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); | |
436 | write_unlock(&resource_lock); | |
437 | return conflict ? -EBUSY : 0; | |
438 | } | |
439 | ||
440 | /** | |
441 | * insert_resource_expand_to_fit - Insert a resource into the resource tree | |
6781f4ae | 442 | * @root: root resource descriptor |
bef69ea0 LT |
443 | * @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 | */ | |
448 | void 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 | } | |
1da177e4 | 471 | write_unlock(&resource_lock); |
1da177e4 LT |
472 | } |
473 | ||
e1ca66d1 RD |
474 | /** |
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 | * | |
1da177e4 | 480 | * Given an existing resource, change its start and size to match the |
e1ca66d1 RD |
481 | * arguments. Returns 0 on success, -EBUSY if it can't fit. |
482 | * Existing children of the resource are assumed to be immutable. | |
1da177e4 | 483 | */ |
d75fc8bb | 484 | int adjust_resource(struct resource *res, resource_size_t start, resource_size_t size) |
1da177e4 LT |
485 | { |
486 | struct resource *tmp, *parent = res->parent; | |
d75fc8bb | 487 | resource_size_t end = start + size - 1; |
1da177e4 LT |
488 | 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 | ||
268364a0 YL |
520 | static 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; | |
42c02023 | 526 | struct resource *res = kzalloc(sizeof(*res), GFP_ATOMIC); |
268364a0 YL |
527 | |
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) { | |
268364a0 YL |
553 | /* failed, split and try again */ |
554 | ||
1cf44baa | 555 | /* conflict covered whole area */ |
268364a0 YL |
556 | 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 | ||
bea92112 | 575 | void __init reserve_region_with_split(struct resource *root, |
268364a0 YL |
576 | 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 | ||
1da177e4 LT |
584 | EXPORT_SYMBOL(adjust_resource); |
585 | ||
88452565 IK |
586 | /** |
587 | * resource_alignment - calculate resource's alignment | |
588 | * @res: resource pointer | |
589 | * | |
590 | * Returns alignment on success, 0 (invalid alignment) on failure. | |
591 | */ | |
592 | resource_size_t resource_alignment(struct resource *res) | |
593 | { | |
594 | switch (res->flags & (IORESOURCE_SIZEALIGN | IORESOURCE_STARTALIGN)) { | |
595 | case IORESOURCE_SIZEALIGN: | |
1a4e564b | 596 | return resource_size(res); |
88452565 IK |
597 | case IORESOURCE_STARTALIGN: |
598 | return res->start; | |
599 | default: | |
600 | return 0; | |
601 | } | |
602 | } | |
603 | ||
1da177e4 LT |
604 | /* |
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 | * | |
e1ca66d1 | 610 | * request_region creates a new busy region. |
1da177e4 | 611 | * |
e1ca66d1 | 612 | * check_region returns non-zero if the area is already busy. |
1da177e4 | 613 | * |
e1ca66d1 RD |
614 | * 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 | |
1da177e4 | 623 | */ |
d75fc8bb GKH |
624 | struct resource * __request_region(struct resource *parent, |
625 | resource_size_t start, resource_size_t n, | |
626 | const char *name) | |
1da177e4 | 627 | { |
dd392710 | 628 | struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL); |
1da177e4 | 629 | |
c26ec88e BH |
630 | if (!res) |
631 | return NULL; | |
632 | ||
633 | res->name = name; | |
634 | res->start = start; | |
635 | res->end = start + n - 1; | |
636 | res->flags = IORESOURCE_BUSY; | |
637 | ||
638 | write_lock(&resource_lock); | |
639 | ||
640 | for (;;) { | |
641 | struct resource *conflict; | |
642 | ||
643 | conflict = __request_resource(parent, res); | |
644 | if (!conflict) | |
1da177e4 | 645 | break; |
c26ec88e BH |
646 | if (conflict != parent) { |
647 | parent = conflict; | |
648 | if (!(conflict->flags & IORESOURCE_BUSY)) | |
649 | continue; | |
1da177e4 | 650 | } |
c26ec88e BH |
651 | |
652 | /* Uhhuh, that didn't work out.. */ | |
653 | kfree(res); | |
654 | res = NULL; | |
655 | break; | |
1da177e4 | 656 | } |
c26ec88e | 657 | write_unlock(&resource_lock); |
1da177e4 LT |
658 | return res; |
659 | } | |
1da177e4 LT |
660 | EXPORT_SYMBOL(__request_region); |
661 | ||
e1ca66d1 RD |
662 | /** |
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 | */ | |
d75fc8bb GKH |
677 | int __check_region(struct resource *parent, resource_size_t start, |
678 | resource_size_t n) | |
1da177e4 LT |
679 | { |
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 | } | |
1da177e4 LT |
690 | EXPORT_SYMBOL(__check_region); |
691 | ||
e1ca66d1 RD |
692 | /** |
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 | */ | |
d75fc8bb GKH |
700 | void __release_region(struct resource *parent, resource_size_t start, |
701 | resource_size_t n) | |
1da177e4 LT |
702 | { |
703 | struct resource **p; | |
d75fc8bb | 704 | resource_size_t end; |
1da177e4 LT |
705 | |
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 | ||
685143ac GKH |
733 | printk(KERN_WARNING "Trying to free nonexistent resource " |
734 | "<%016llx-%016llx>\n", (unsigned long long)start, | |
735 | (unsigned long long)end); | |
1da177e4 | 736 | } |
1da177e4 LT |
737 | EXPORT_SYMBOL(__release_region); |
738 | ||
9ac7849e TH |
739 | /* |
740 | * Managed region resource | |
741 | */ | |
742 | struct region_devres { | |
743 | struct resource *parent; | |
744 | resource_size_t start; | |
745 | resource_size_t n; | |
746 | }; | |
747 | ||
748 | static 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 | ||
755 | static 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 | ||
763 | struct 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 | } | |
787 | EXPORT_SYMBOL(__devm_request_region); | |
788 | ||
789 | void __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 | } | |
798 | EXPORT_SYMBOL(__devm_release_region); | |
799 | ||
1da177e4 LT |
800 | /* |
801 | * Called from init/main.c to reserve IO ports. | |
802 | */ | |
803 | #define MAXRESERVE 4 | |
804 | static 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); | |
379daf62 SS |
832 | |
833 | /* | |
834 | * Check if the requested addr and size spans more than any slot in the | |
835 | * iomem resource tree. | |
836 | */ | |
837 | int 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; | |
d68612b2 SS |
853 | if (PFN_DOWN(p->start) <= PFN_DOWN(addr) && |
854 | PFN_DOWN(p->end) >= PFN_DOWN(addr + size - 1)) | |
379daf62 SS |
855 | continue; |
856 | printk(KERN_WARNING "resource map sanity check conflict: " | |
857 | "0x%llx 0x%llx 0x%llx 0x%llx %s\n", | |
13eb8375 IM |
858 | (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); | |
379daf62 SS |
863 | err = -1; |
864 | break; | |
865 | } | |
866 | read_unlock(&resource_lock); | |
867 | ||
868 | return err; | |
869 | } |