]>
Commit | Line | Data |
---|---|---|
1 | /* | |
2 | * linux/kernel/resource.c | |
3 | * | |
4 | * Copyright (C) 1999 Linus Torvalds | |
5 | * Copyright (C) 1999 Martin Mares <mj@ucw.cz> | |
6 | * | |
7 | * Arbitrary resource management. | |
8 | */ | |
9 | ||
10 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | |
11 | ||
12 | #include <linux/export.h> | |
13 | #include <linux/errno.h> | |
14 | #include <linux/ioport.h> | |
15 | #include <linux/init.h> | |
16 | #include <linux/slab.h> | |
17 | #include <linux/spinlock.h> | |
18 | #include <linux/fs.h> | |
19 | #include <linux/proc_fs.h> | |
20 | #include <linux/sched.h> | |
21 | #include <linux/seq_file.h> | |
22 | #include <linux/device.h> | |
23 | #include <linux/pfn.h> | |
24 | #include <linux/mm.h> | |
25 | #include <linux/resource_ext.h> | |
26 | #include <asm/io.h> | |
27 | ||
28 | ||
29 | struct resource ioport_resource = { | |
30 | .name = "PCI IO", | |
31 | .start = 0, | |
32 | .end = IO_SPACE_LIMIT, | |
33 | .flags = IORESOURCE_IO, | |
34 | }; | |
35 | EXPORT_SYMBOL(ioport_resource); | |
36 | ||
37 | struct resource iomem_resource = { | |
38 | .name = "PCI mem", | |
39 | .start = 0, | |
40 | .end = -1, | |
41 | .flags = IORESOURCE_MEM, | |
42 | }; | |
43 | EXPORT_SYMBOL(iomem_resource); | |
44 | ||
45 | /* constraints to be met while allocating resources */ | |
46 | struct resource_constraint { | |
47 | resource_size_t min, max, align; | |
48 | resource_size_t (*alignf)(void *, const struct resource *, | |
49 | resource_size_t, resource_size_t); | |
50 | void *alignf_data; | |
51 | }; | |
52 | ||
53 | static DEFINE_RWLOCK(resource_lock); | |
54 | ||
55 | /* | |
56 | * For memory hotplug, there is no way to free resource entries allocated | |
57 | * by boot mem after the system is up. So for reusing the resource entry | |
58 | * we need to remember the resource. | |
59 | */ | |
60 | static struct resource *bootmem_resource_free; | |
61 | static DEFINE_SPINLOCK(bootmem_resource_lock); | |
62 | ||
63 | static struct resource *next_resource(struct resource *p, bool sibling_only) | |
64 | { | |
65 | /* Caller wants to traverse through siblings only */ | |
66 | if (sibling_only) | |
67 | return p->sibling; | |
68 | ||
69 | if (p->child) | |
70 | return p->child; | |
71 | while (!p->sibling && p->parent) | |
72 | p = p->parent; | |
73 | return p->sibling; | |
74 | } | |
75 | ||
76 | static void *r_next(struct seq_file *m, void *v, loff_t *pos) | |
77 | { | |
78 | struct resource *p = v; | |
79 | (*pos)++; | |
80 | return (void *)next_resource(p, false); | |
81 | } | |
82 | ||
83 | #ifdef CONFIG_PROC_FS | |
84 | ||
85 | enum { MAX_IORES_LEVEL = 5 }; | |
86 | ||
87 | static void *r_start(struct seq_file *m, loff_t *pos) | |
88 | __acquires(resource_lock) | |
89 | { | |
90 | struct resource *p = m->private; | |
91 | loff_t l = 0; | |
92 | read_lock(&resource_lock); | |
93 | for (p = p->child; p && l < *pos; p = r_next(m, p, &l)) | |
94 | ; | |
95 | return p; | |
96 | } | |
97 | ||
98 | static void r_stop(struct seq_file *m, void *v) | |
99 | __releases(resource_lock) | |
100 | { | |
101 | read_unlock(&resource_lock); | |
102 | } | |
103 | ||
104 | static int r_show(struct seq_file *m, void *v) | |
105 | { | |
106 | struct resource *root = m->private; | |
107 | struct resource *r = v, *p; | |
108 | unsigned long long start, end; | |
109 | int width = root->end < 0x10000 ? 4 : 8; | |
110 | int depth; | |
111 | ||
112 | for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent) | |
113 | if (p->parent == root) | |
114 | break; | |
115 | ||
116 | if (file_ns_capable(m->file, &init_user_ns, CAP_SYS_ADMIN)) { | |
117 | start = r->start; | |
118 | end = r->end; | |
119 | } else { | |
120 | start = end = 0; | |
121 | } | |
122 | ||
123 | seq_printf(m, "%*s%0*llx-%0*llx : %s\n", | |
124 | depth * 2, "", | |
125 | width, start, | |
126 | width, end, | |
127 | r->name ? r->name : "<BAD>"); | |
128 | return 0; | |
129 | } | |
130 | ||
131 | static const struct seq_operations resource_op = { | |
132 | .start = r_start, | |
133 | .next = r_next, | |
134 | .stop = r_stop, | |
135 | .show = r_show, | |
136 | }; | |
137 | ||
138 | static int ioports_open(struct inode *inode, struct file *file) | |
139 | { | |
140 | int res = seq_open(file, &resource_op); | |
141 | if (!res) { | |
142 | struct seq_file *m = file->private_data; | |
143 | m->private = &ioport_resource; | |
144 | } | |
145 | return res; | |
146 | } | |
147 | ||
148 | static int iomem_open(struct inode *inode, struct file *file) | |
149 | { | |
150 | int res = seq_open(file, &resource_op); | |
151 | if (!res) { | |
152 | struct seq_file *m = file->private_data; | |
153 | m->private = &iomem_resource; | |
154 | } | |
155 | return res; | |
156 | } | |
157 | ||
158 | static const struct file_operations proc_ioports_operations = { | |
159 | .open = ioports_open, | |
160 | .read = seq_read, | |
161 | .llseek = seq_lseek, | |
162 | .release = seq_release, | |
163 | }; | |
164 | ||
165 | static const struct file_operations proc_iomem_operations = { | |
166 | .open = iomem_open, | |
167 | .read = seq_read, | |
168 | .llseek = seq_lseek, | |
169 | .release = seq_release, | |
170 | }; | |
171 | ||
172 | static int __init ioresources_init(void) | |
173 | { | |
174 | proc_create("ioports", 0, NULL, &proc_ioports_operations); | |
175 | proc_create("iomem", 0, NULL, &proc_iomem_operations); | |
176 | return 0; | |
177 | } | |
178 | __initcall(ioresources_init); | |
179 | ||
180 | #endif /* CONFIG_PROC_FS */ | |
181 | ||
182 | static void free_resource(struct resource *res) | |
183 | { | |
184 | if (!res) | |
185 | return; | |
186 | ||
187 | if (!PageSlab(virt_to_head_page(res))) { | |
188 | spin_lock(&bootmem_resource_lock); | |
189 | res->sibling = bootmem_resource_free; | |
190 | bootmem_resource_free = res; | |
191 | spin_unlock(&bootmem_resource_lock); | |
192 | } else { | |
193 | kfree(res); | |
194 | } | |
195 | } | |
196 | ||
197 | static struct resource *alloc_resource(gfp_t flags) | |
198 | { | |
199 | struct resource *res = NULL; | |
200 | ||
201 | spin_lock(&bootmem_resource_lock); | |
202 | if (bootmem_resource_free) { | |
203 | res = bootmem_resource_free; | |
204 | bootmem_resource_free = res->sibling; | |
205 | } | |
206 | spin_unlock(&bootmem_resource_lock); | |
207 | ||
208 | if (res) | |
209 | memset(res, 0, sizeof(struct resource)); | |
210 | else | |
211 | res = kzalloc(sizeof(struct resource), flags); | |
212 | ||
213 | return res; | |
214 | } | |
215 | ||
216 | /* Return the conflict entry if you can't request it */ | |
217 | static struct resource * __request_resource(struct resource *root, struct resource *new) | |
218 | { | |
219 | resource_size_t start = new->start; | |
220 | resource_size_t end = new->end; | |
221 | struct resource *tmp, **p; | |
222 | ||
223 | if (end < start) | |
224 | return root; | |
225 | if (start < root->start) | |
226 | return root; | |
227 | if (end > root->end) | |
228 | return root; | |
229 | p = &root->child; | |
230 | for (;;) { | |
231 | tmp = *p; | |
232 | if (!tmp || tmp->start > end) { | |
233 | new->sibling = tmp; | |
234 | *p = new; | |
235 | new->parent = root; | |
236 | return NULL; | |
237 | } | |
238 | p = &tmp->sibling; | |
239 | if (tmp->end < start) | |
240 | continue; | |
241 | return tmp; | |
242 | } | |
243 | } | |
244 | ||
245 | static int __release_resource(struct resource *old, bool release_child) | |
246 | { | |
247 | struct resource *tmp, **p, *chd; | |
248 | ||
249 | if (!old->parent) { | |
250 | WARN(old->sibling, "sibling but no parent"); | |
251 | if (old->sibling) | |
252 | return -EINVAL; | |
253 | return 0; | |
254 | } | |
255 | p = &old->parent->child; | |
256 | for (;;) { | |
257 | tmp = *p; | |
258 | if (!tmp) | |
259 | break; | |
260 | if (tmp == old) { | |
261 | if (release_child || !(tmp->child)) { | |
262 | *p = tmp->sibling; | |
263 | } else { | |
264 | for (chd = tmp->child;; chd = chd->sibling) { | |
265 | chd->parent = tmp->parent; | |
266 | if (!(chd->sibling)) | |
267 | break; | |
268 | } | |
269 | *p = tmp->child; | |
270 | chd->sibling = tmp->sibling; | |
271 | } | |
272 | old->parent = NULL; | |
273 | return 0; | |
274 | } | |
275 | p = &tmp->sibling; | |
276 | } | |
277 | return -EINVAL; | |
278 | } | |
279 | ||
280 | static void __release_child_resources(struct resource *r) | |
281 | { | |
282 | struct resource *tmp, *p; | |
283 | resource_size_t size; | |
284 | ||
285 | p = r->child; | |
286 | r->child = NULL; | |
287 | while (p) { | |
288 | tmp = p; | |
289 | p = p->sibling; | |
290 | ||
291 | tmp->parent = NULL; | |
292 | tmp->sibling = NULL; | |
293 | __release_child_resources(tmp); | |
294 | ||
295 | printk(KERN_DEBUG "release child resource %pR\n", tmp); | |
296 | /* need to restore size, and keep flags */ | |
297 | size = resource_size(tmp); | |
298 | tmp->start = 0; | |
299 | tmp->end = size - 1; | |
300 | } | |
301 | } | |
302 | ||
303 | void release_child_resources(struct resource *r) | |
304 | { | |
305 | write_lock(&resource_lock); | |
306 | __release_child_resources(r); | |
307 | write_unlock(&resource_lock); | |
308 | } | |
309 | ||
310 | /** | |
311 | * request_resource_conflict - request and reserve an I/O or memory resource | |
312 | * @root: root resource descriptor | |
313 | * @new: resource descriptor desired by caller | |
314 | * | |
315 | * Returns 0 for success, conflict resource on error. | |
316 | */ | |
317 | struct resource *request_resource_conflict(struct resource *root, struct resource *new) | |
318 | { | |
319 | struct resource *conflict; | |
320 | ||
321 | write_lock(&resource_lock); | |
322 | conflict = __request_resource(root, new); | |
323 | write_unlock(&resource_lock); | |
324 | return conflict; | |
325 | } | |
326 | ||
327 | /** | |
328 | * request_resource - request and reserve an I/O or memory resource | |
329 | * @root: root resource descriptor | |
330 | * @new: resource descriptor desired by caller | |
331 | * | |
332 | * Returns 0 for success, negative error code on error. | |
333 | */ | |
334 | int request_resource(struct resource *root, struct resource *new) | |
335 | { | |
336 | struct resource *conflict; | |
337 | ||
338 | conflict = request_resource_conflict(root, new); | |
339 | return conflict ? -EBUSY : 0; | |
340 | } | |
341 | ||
342 | EXPORT_SYMBOL(request_resource); | |
343 | ||
344 | /** | |
345 | * release_resource - release a previously reserved resource | |
346 | * @old: resource pointer | |
347 | */ | |
348 | int release_resource(struct resource *old) | |
349 | { | |
350 | int retval; | |
351 | ||
352 | write_lock(&resource_lock); | |
353 | retval = __release_resource(old, true); | |
354 | write_unlock(&resource_lock); | |
355 | return retval; | |
356 | } | |
357 | ||
358 | EXPORT_SYMBOL(release_resource); | |
359 | ||
360 | /* | |
361 | * Finds the lowest iomem resource existing within [res->start.res->end). | |
362 | * The caller must specify res->start, res->end, res->flags, and optionally | |
363 | * desc. If found, returns 0, res is overwritten, if not found, returns -1. | |
364 | * This function walks the whole tree and not just first level children until | |
365 | * and unless first_level_children_only is true. | |
366 | */ | |
367 | static int find_next_iomem_res(struct resource *res, unsigned long desc, | |
368 | bool first_level_children_only) | |
369 | { | |
370 | resource_size_t start, end; | |
371 | struct resource *p; | |
372 | bool sibling_only = false; | |
373 | ||
374 | BUG_ON(!res); | |
375 | ||
376 | start = res->start; | |
377 | end = res->end; | |
378 | BUG_ON(start >= end); | |
379 | ||
380 | if (first_level_children_only) | |
381 | sibling_only = true; | |
382 | ||
383 | read_lock(&resource_lock); | |
384 | ||
385 | for (p = iomem_resource.child; p; p = next_resource(p, sibling_only)) { | |
386 | if ((p->flags & res->flags) != res->flags) | |
387 | continue; | |
388 | if ((desc != IORES_DESC_NONE) && (desc != p->desc)) | |
389 | continue; | |
390 | if (p->start > end) { | |
391 | p = NULL; | |
392 | break; | |
393 | } | |
394 | if ((p->end >= start) && (p->start < end)) | |
395 | break; | |
396 | } | |
397 | ||
398 | read_unlock(&resource_lock); | |
399 | if (!p) | |
400 | return -1; | |
401 | /* copy data */ | |
402 | if (res->start < p->start) | |
403 | res->start = p->start; | |
404 | if (res->end > p->end) | |
405 | res->end = p->end; | |
406 | return 0; | |
407 | } | |
408 | ||
409 | /* | |
410 | * Walks through iomem resources and calls func() with matching resource | |
411 | * ranges. This walks through whole tree and not just first level children. | |
412 | * All the memory ranges which overlap start,end and also match flags and | |
413 | * desc are valid candidates. | |
414 | * | |
415 | * @desc: I/O resource descriptor. Use IORES_DESC_NONE to skip @desc check. | |
416 | * @flags: I/O resource flags | |
417 | * @start: start addr | |
418 | * @end: end addr | |
419 | * | |
420 | * NOTE: For a new descriptor search, define a new IORES_DESC in | |
421 | * <linux/ioport.h> and set it in 'desc' of a target resource entry. | |
422 | */ | |
423 | int walk_iomem_res_desc(unsigned long desc, unsigned long flags, u64 start, | |
424 | u64 end, void *arg, int (*func)(u64, u64, void *)) | |
425 | { | |
426 | struct resource res; | |
427 | u64 orig_end; | |
428 | int ret = -1; | |
429 | ||
430 | res.start = start; | |
431 | res.end = end; | |
432 | res.flags = flags; | |
433 | orig_end = res.end; | |
434 | ||
435 | while ((res.start < res.end) && | |
436 | (!find_next_iomem_res(&res, desc, false))) { | |
437 | ||
438 | ret = (*func)(res.start, res.end, arg); | |
439 | if (ret) | |
440 | break; | |
441 | ||
442 | res.start = res.end + 1; | |
443 | res.end = orig_end; | |
444 | } | |
445 | ||
446 | return ret; | |
447 | } | |
448 | ||
449 | /* | |
450 | * This function calls the @func callback against all memory ranges of type | |
451 | * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY. | |
452 | * Now, this function is only for System RAM, it deals with full ranges and | |
453 | * not PFNs. If resources are not PFN-aligned, dealing with PFNs can truncate | |
454 | * ranges. | |
455 | */ | |
456 | int walk_system_ram_res(u64 start, u64 end, void *arg, | |
457 | int (*func)(u64, u64, void *)) | |
458 | { | |
459 | struct resource res; | |
460 | u64 orig_end; | |
461 | int ret = -1; | |
462 | ||
463 | res.start = start; | |
464 | res.end = end; | |
465 | res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; | |
466 | orig_end = res.end; | |
467 | while ((res.start < res.end) && | |
468 | (!find_next_iomem_res(&res, IORES_DESC_NONE, true))) { | |
469 | ret = (*func)(res.start, res.end, arg); | |
470 | if (ret) | |
471 | break; | |
472 | res.start = res.end + 1; | |
473 | res.end = orig_end; | |
474 | } | |
475 | return ret; | |
476 | } | |
477 | ||
478 | #if !defined(CONFIG_ARCH_HAS_WALK_MEMORY) | |
479 | ||
480 | /* | |
481 | * This function calls the @func callback against all memory ranges of type | |
482 | * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY. | |
483 | * It is to be used only for System RAM. | |
484 | */ | |
485 | int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, | |
486 | void *arg, int (*func)(unsigned long, unsigned long, void *)) | |
487 | { | |
488 | struct resource res; | |
489 | unsigned long pfn, end_pfn; | |
490 | u64 orig_end; | |
491 | int ret = -1; | |
492 | ||
493 | res.start = (u64) start_pfn << PAGE_SHIFT; | |
494 | res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1; | |
495 | res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; | |
496 | orig_end = res.end; | |
497 | while ((res.start < res.end) && | |
498 | (find_next_iomem_res(&res, IORES_DESC_NONE, true) >= 0)) { | |
499 | pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
500 | end_pfn = (res.end + 1) >> PAGE_SHIFT; | |
501 | if (end_pfn > pfn) | |
502 | ret = (*func)(pfn, end_pfn - pfn, arg); | |
503 | if (ret) | |
504 | break; | |
505 | res.start = res.end + 1; | |
506 | res.end = orig_end; | |
507 | } | |
508 | return ret; | |
509 | } | |
510 | ||
511 | #endif | |
512 | ||
513 | static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg) | |
514 | { | |
515 | return 1; | |
516 | } | |
517 | /* | |
518 | * This generic page_is_ram() returns true if specified address is | |
519 | * registered as System RAM in iomem_resource list. | |
520 | */ | |
521 | int __weak page_is_ram(unsigned long pfn) | |
522 | { | |
523 | return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1; | |
524 | } | |
525 | EXPORT_SYMBOL_GPL(page_is_ram); | |
526 | ||
527 | /** | |
528 | * region_intersects() - determine intersection of region with known resources | |
529 | * @start: region start address | |
530 | * @size: size of region | |
531 | * @flags: flags of resource (in iomem_resource) | |
532 | * @desc: descriptor of resource (in iomem_resource) or IORES_DESC_NONE | |
533 | * | |
534 | * Check if the specified region partially overlaps or fully eclipses a | |
535 | * resource identified by @flags and @desc (optional with IORES_DESC_NONE). | |
536 | * Return REGION_DISJOINT if the region does not overlap @flags/@desc, | |
537 | * return REGION_MIXED if the region overlaps @flags/@desc and another | |
538 | * resource, and return REGION_INTERSECTS if the region overlaps @flags/@desc | |
539 | * and no other defined resource. Note that REGION_INTERSECTS is also | |
540 | * returned in the case when the specified region overlaps RAM and undefined | |
541 | * memory holes. | |
542 | * | |
543 | * region_intersect() is used by memory remapping functions to ensure | |
544 | * the user is not remapping RAM and is a vast speed up over walking | |
545 | * through the resource table page by page. | |
546 | */ | |
547 | int region_intersects(resource_size_t start, size_t size, unsigned long flags, | |
548 | unsigned long desc) | |
549 | { | |
550 | resource_size_t end = start + size - 1; | |
551 | int type = 0; int other = 0; | |
552 | struct resource *p; | |
553 | ||
554 | read_lock(&resource_lock); | |
555 | for (p = iomem_resource.child; p ; p = p->sibling) { | |
556 | bool is_type = (((p->flags & flags) == flags) && | |
557 | ((desc == IORES_DESC_NONE) || | |
558 | (desc == p->desc))); | |
559 | ||
560 | if (start >= p->start && start <= p->end) | |
561 | is_type ? type++ : other++; | |
562 | if (end >= p->start && end <= p->end) | |
563 | is_type ? type++ : other++; | |
564 | if (p->start >= start && p->end <= end) | |
565 | is_type ? type++ : other++; | |
566 | } | |
567 | read_unlock(&resource_lock); | |
568 | ||
569 | if (other == 0) | |
570 | return type ? REGION_INTERSECTS : REGION_DISJOINT; | |
571 | ||
572 | if (type) | |
573 | return REGION_MIXED; | |
574 | ||
575 | return REGION_DISJOINT; | |
576 | } | |
577 | EXPORT_SYMBOL_GPL(region_intersects); | |
578 | ||
579 | void __weak arch_remove_reservations(struct resource *avail) | |
580 | { | |
581 | } | |
582 | ||
583 | static resource_size_t simple_align_resource(void *data, | |
584 | const struct resource *avail, | |
585 | resource_size_t size, | |
586 | resource_size_t align) | |
587 | { | |
588 | return avail->start; | |
589 | } | |
590 | ||
591 | static void resource_clip(struct resource *res, resource_size_t min, | |
592 | resource_size_t max) | |
593 | { | |
594 | if (res->start < min) | |
595 | res->start = min; | |
596 | if (res->end > max) | |
597 | res->end = max; | |
598 | } | |
599 | ||
600 | /* | |
601 | * Find empty slot in the resource tree with the given range and | |
602 | * alignment constraints | |
603 | */ | |
604 | static int __find_resource(struct resource *root, struct resource *old, | |
605 | struct resource *new, | |
606 | resource_size_t size, | |
607 | struct resource_constraint *constraint) | |
608 | { | |
609 | struct resource *this = root->child; | |
610 | struct resource tmp = *new, avail, alloc; | |
611 | ||
612 | tmp.start = root->start; | |
613 | /* | |
614 | * Skip past an allocated resource that starts at 0, since the assignment | |
615 | * of this->start - 1 to tmp->end below would cause an underflow. | |
616 | */ | |
617 | if (this && this->start == root->start) { | |
618 | tmp.start = (this == old) ? old->start : this->end + 1; | |
619 | this = this->sibling; | |
620 | } | |
621 | for(;;) { | |
622 | if (this) | |
623 | tmp.end = (this == old) ? this->end : this->start - 1; | |
624 | else | |
625 | tmp.end = root->end; | |
626 | ||
627 | if (tmp.end < tmp.start) | |
628 | goto next; | |
629 | ||
630 | resource_clip(&tmp, constraint->min, constraint->max); | |
631 | arch_remove_reservations(&tmp); | |
632 | ||
633 | /* Check for overflow after ALIGN() */ | |
634 | avail.start = ALIGN(tmp.start, constraint->align); | |
635 | avail.end = tmp.end; | |
636 | avail.flags = new->flags & ~IORESOURCE_UNSET; | |
637 | if (avail.start >= tmp.start) { | |
638 | alloc.flags = avail.flags; | |
639 | alloc.start = constraint->alignf(constraint->alignf_data, &avail, | |
640 | size, constraint->align); | |
641 | alloc.end = alloc.start + size - 1; | |
642 | if (resource_contains(&avail, &alloc)) { | |
643 | new->start = alloc.start; | |
644 | new->end = alloc.end; | |
645 | return 0; | |
646 | } | |
647 | } | |
648 | ||
649 | next: if (!this || this->end == root->end) | |
650 | break; | |
651 | ||
652 | if (this != old) | |
653 | tmp.start = this->end + 1; | |
654 | this = this->sibling; | |
655 | } | |
656 | return -EBUSY; | |
657 | } | |
658 | ||
659 | /* | |
660 | * Find empty slot in the resource tree given range and alignment. | |
661 | */ | |
662 | static int find_resource(struct resource *root, struct resource *new, | |
663 | resource_size_t size, | |
664 | struct resource_constraint *constraint) | |
665 | { | |
666 | return __find_resource(root, NULL, new, size, constraint); | |
667 | } | |
668 | ||
669 | /** | |
670 | * reallocate_resource - allocate a slot in the resource tree given range & alignment. | |
671 | * The resource will be relocated if the new size cannot be reallocated in the | |
672 | * current location. | |
673 | * | |
674 | * @root: root resource descriptor | |
675 | * @old: resource descriptor desired by caller | |
676 | * @newsize: new size of the resource descriptor | |
677 | * @constraint: the size and alignment constraints to be met. | |
678 | */ | |
679 | static int reallocate_resource(struct resource *root, struct resource *old, | |
680 | resource_size_t newsize, | |
681 | struct resource_constraint *constraint) | |
682 | { | |
683 | int err=0; | |
684 | struct resource new = *old; | |
685 | struct resource *conflict; | |
686 | ||
687 | write_lock(&resource_lock); | |
688 | ||
689 | if ((err = __find_resource(root, old, &new, newsize, constraint))) | |
690 | goto out; | |
691 | ||
692 | if (resource_contains(&new, old)) { | |
693 | old->start = new.start; | |
694 | old->end = new.end; | |
695 | goto out; | |
696 | } | |
697 | ||
698 | if (old->child) { | |
699 | err = -EBUSY; | |
700 | goto out; | |
701 | } | |
702 | ||
703 | if (resource_contains(old, &new)) { | |
704 | old->start = new.start; | |
705 | old->end = new.end; | |
706 | } else { | |
707 | __release_resource(old, true); | |
708 | *old = new; | |
709 | conflict = __request_resource(root, old); | |
710 | BUG_ON(conflict); | |
711 | } | |
712 | out: | |
713 | write_unlock(&resource_lock); | |
714 | return err; | |
715 | } | |
716 | ||
717 | ||
718 | /** | |
719 | * allocate_resource - allocate empty slot in the resource tree given range & alignment. | |
720 | * The resource will be reallocated with a new size if it was already allocated | |
721 | * @root: root resource descriptor | |
722 | * @new: resource descriptor desired by caller | |
723 | * @size: requested resource region size | |
724 | * @min: minimum boundary to allocate | |
725 | * @max: maximum boundary to allocate | |
726 | * @align: alignment requested, in bytes | |
727 | * @alignf: alignment function, optional, called if not NULL | |
728 | * @alignf_data: arbitrary data to pass to the @alignf function | |
729 | */ | |
730 | int allocate_resource(struct resource *root, struct resource *new, | |
731 | resource_size_t size, resource_size_t min, | |
732 | resource_size_t max, resource_size_t align, | |
733 | resource_size_t (*alignf)(void *, | |
734 | const struct resource *, | |
735 | resource_size_t, | |
736 | resource_size_t), | |
737 | void *alignf_data) | |
738 | { | |
739 | int err; | |
740 | struct resource_constraint constraint; | |
741 | ||
742 | if (!alignf) | |
743 | alignf = simple_align_resource; | |
744 | ||
745 | constraint.min = min; | |
746 | constraint.max = max; | |
747 | constraint.align = align; | |
748 | constraint.alignf = alignf; | |
749 | constraint.alignf_data = alignf_data; | |
750 | ||
751 | if ( new->parent ) { | |
752 | /* resource is already allocated, try reallocating with | |
753 | the new constraints */ | |
754 | return reallocate_resource(root, new, size, &constraint); | |
755 | } | |
756 | ||
757 | write_lock(&resource_lock); | |
758 | err = find_resource(root, new, size, &constraint); | |
759 | if (err >= 0 && __request_resource(root, new)) | |
760 | err = -EBUSY; | |
761 | write_unlock(&resource_lock); | |
762 | return err; | |
763 | } | |
764 | ||
765 | EXPORT_SYMBOL(allocate_resource); | |
766 | ||
767 | /** | |
768 | * lookup_resource - find an existing resource by a resource start address | |
769 | * @root: root resource descriptor | |
770 | * @start: resource start address | |
771 | * | |
772 | * Returns a pointer to the resource if found, NULL otherwise | |
773 | */ | |
774 | struct resource *lookup_resource(struct resource *root, resource_size_t start) | |
775 | { | |
776 | struct resource *res; | |
777 | ||
778 | read_lock(&resource_lock); | |
779 | for (res = root->child; res; res = res->sibling) { | |
780 | if (res->start == start) | |
781 | break; | |
782 | } | |
783 | read_unlock(&resource_lock); | |
784 | ||
785 | return res; | |
786 | } | |
787 | ||
788 | /* | |
789 | * Insert a resource into the resource tree. If successful, return NULL, | |
790 | * otherwise return the conflicting resource (compare to __request_resource()) | |
791 | */ | |
792 | static struct resource * __insert_resource(struct resource *parent, struct resource *new) | |
793 | { | |
794 | struct resource *first, *next; | |
795 | ||
796 | for (;; parent = first) { | |
797 | first = __request_resource(parent, new); | |
798 | if (!first) | |
799 | return first; | |
800 | ||
801 | if (first == parent) | |
802 | return first; | |
803 | if (WARN_ON(first == new)) /* duplicated insertion */ | |
804 | return first; | |
805 | ||
806 | if ((first->start > new->start) || (first->end < new->end)) | |
807 | break; | |
808 | if ((first->start == new->start) && (first->end == new->end)) | |
809 | break; | |
810 | } | |
811 | ||
812 | for (next = first; ; next = next->sibling) { | |
813 | /* Partial overlap? Bad, and unfixable */ | |
814 | if (next->start < new->start || next->end > new->end) | |
815 | return next; | |
816 | if (!next->sibling) | |
817 | break; | |
818 | if (next->sibling->start > new->end) | |
819 | break; | |
820 | } | |
821 | ||
822 | new->parent = parent; | |
823 | new->sibling = next->sibling; | |
824 | new->child = first; | |
825 | ||
826 | next->sibling = NULL; | |
827 | for (next = first; next; next = next->sibling) | |
828 | next->parent = new; | |
829 | ||
830 | if (parent->child == first) { | |
831 | parent->child = new; | |
832 | } else { | |
833 | next = parent->child; | |
834 | while (next->sibling != first) | |
835 | next = next->sibling; | |
836 | next->sibling = new; | |
837 | } | |
838 | return NULL; | |
839 | } | |
840 | ||
841 | /** | |
842 | * insert_resource_conflict - Inserts resource in the resource tree | |
843 | * @parent: parent of the new resource | |
844 | * @new: new resource to insert | |
845 | * | |
846 | * Returns 0 on success, conflict resource if the resource can't be inserted. | |
847 | * | |
848 | * This function is equivalent to request_resource_conflict when no conflict | |
849 | * happens. If a conflict happens, and the conflicting resources | |
850 | * entirely fit within the range of the new resource, then the new | |
851 | * resource is inserted and the conflicting resources become children of | |
852 | * the new resource. | |
853 | * | |
854 | * This function is intended for producers of resources, such as FW modules | |
855 | * and bus drivers. | |
856 | */ | |
857 | struct resource *insert_resource_conflict(struct resource *parent, struct resource *new) | |
858 | { | |
859 | struct resource *conflict; | |
860 | ||
861 | write_lock(&resource_lock); | |
862 | conflict = __insert_resource(parent, new); | |
863 | write_unlock(&resource_lock); | |
864 | return conflict; | |
865 | } | |
866 | ||
867 | /** | |
868 | * insert_resource - Inserts a resource in the resource tree | |
869 | * @parent: parent of the new resource | |
870 | * @new: new resource to insert | |
871 | * | |
872 | * Returns 0 on success, -EBUSY if the resource can't be inserted. | |
873 | * | |
874 | * This function is intended for producers of resources, such as FW modules | |
875 | * and bus drivers. | |
876 | */ | |
877 | int insert_resource(struct resource *parent, struct resource *new) | |
878 | { | |
879 | struct resource *conflict; | |
880 | ||
881 | conflict = insert_resource_conflict(parent, new); | |
882 | return conflict ? -EBUSY : 0; | |
883 | } | |
884 | EXPORT_SYMBOL_GPL(insert_resource); | |
885 | ||
886 | /** | |
887 | * insert_resource_expand_to_fit - Insert a resource into the resource tree | |
888 | * @root: root resource descriptor | |
889 | * @new: new resource to insert | |
890 | * | |
891 | * Insert a resource into the resource tree, possibly expanding it in order | |
892 | * to make it encompass any conflicting resources. | |
893 | */ | |
894 | void insert_resource_expand_to_fit(struct resource *root, struct resource *new) | |
895 | { | |
896 | if (new->parent) | |
897 | return; | |
898 | ||
899 | write_lock(&resource_lock); | |
900 | for (;;) { | |
901 | struct resource *conflict; | |
902 | ||
903 | conflict = __insert_resource(root, new); | |
904 | if (!conflict) | |
905 | break; | |
906 | if (conflict == root) | |
907 | break; | |
908 | ||
909 | /* Ok, expand resource to cover the conflict, then try again .. */ | |
910 | if (conflict->start < new->start) | |
911 | new->start = conflict->start; | |
912 | if (conflict->end > new->end) | |
913 | new->end = conflict->end; | |
914 | ||
915 | printk("Expanded resource %s due to conflict with %s\n", new->name, conflict->name); | |
916 | } | |
917 | write_unlock(&resource_lock); | |
918 | } | |
919 | ||
920 | /** | |
921 | * remove_resource - Remove a resource in the resource tree | |
922 | * @old: resource to remove | |
923 | * | |
924 | * Returns 0 on success, -EINVAL if the resource is not valid. | |
925 | * | |
926 | * This function removes a resource previously inserted by insert_resource() | |
927 | * or insert_resource_conflict(), and moves the children (if any) up to | |
928 | * where they were before. insert_resource() and insert_resource_conflict() | |
929 | * insert a new resource, and move any conflicting resources down to the | |
930 | * children of the new resource. | |
931 | * | |
932 | * insert_resource(), insert_resource_conflict() and remove_resource() are | |
933 | * intended for producers of resources, such as FW modules and bus drivers. | |
934 | */ | |
935 | int remove_resource(struct resource *old) | |
936 | { | |
937 | int retval; | |
938 | ||
939 | write_lock(&resource_lock); | |
940 | retval = __release_resource(old, false); | |
941 | write_unlock(&resource_lock); | |
942 | return retval; | |
943 | } | |
944 | EXPORT_SYMBOL_GPL(remove_resource); | |
945 | ||
946 | static int __adjust_resource(struct resource *res, resource_size_t start, | |
947 | resource_size_t size) | |
948 | { | |
949 | struct resource *tmp, *parent = res->parent; | |
950 | resource_size_t end = start + size - 1; | |
951 | int result = -EBUSY; | |
952 | ||
953 | if (!parent) | |
954 | goto skip; | |
955 | ||
956 | if ((start < parent->start) || (end > parent->end)) | |
957 | goto out; | |
958 | ||
959 | if (res->sibling && (res->sibling->start <= end)) | |
960 | goto out; | |
961 | ||
962 | tmp = parent->child; | |
963 | if (tmp != res) { | |
964 | while (tmp->sibling != res) | |
965 | tmp = tmp->sibling; | |
966 | if (start <= tmp->end) | |
967 | goto out; | |
968 | } | |
969 | ||
970 | skip: | |
971 | for (tmp = res->child; tmp; tmp = tmp->sibling) | |
972 | if ((tmp->start < start) || (tmp->end > end)) | |
973 | goto out; | |
974 | ||
975 | res->start = start; | |
976 | res->end = end; | |
977 | result = 0; | |
978 | ||
979 | out: | |
980 | return result; | |
981 | } | |
982 | ||
983 | /** | |
984 | * adjust_resource - modify a resource's start and size | |
985 | * @res: resource to modify | |
986 | * @start: new start value | |
987 | * @size: new size | |
988 | * | |
989 | * Given an existing resource, change its start and size to match the | |
990 | * arguments. Returns 0 on success, -EBUSY if it can't fit. | |
991 | * Existing children of the resource are assumed to be immutable. | |
992 | */ | |
993 | int adjust_resource(struct resource *res, resource_size_t start, | |
994 | resource_size_t size) | |
995 | { | |
996 | int result; | |
997 | ||
998 | write_lock(&resource_lock); | |
999 | result = __adjust_resource(res, start, size); | |
1000 | write_unlock(&resource_lock); | |
1001 | return result; | |
1002 | } | |
1003 | EXPORT_SYMBOL(adjust_resource); | |
1004 | ||
1005 | static void __init __reserve_region_with_split(struct resource *root, | |
1006 | resource_size_t start, resource_size_t end, | |
1007 | const char *name) | |
1008 | { | |
1009 | struct resource *parent = root; | |
1010 | struct resource *conflict; | |
1011 | struct resource *res = alloc_resource(GFP_ATOMIC); | |
1012 | struct resource *next_res = NULL; | |
1013 | ||
1014 | if (!res) | |
1015 | return; | |
1016 | ||
1017 | res->name = name; | |
1018 | res->start = start; | |
1019 | res->end = end; | |
1020 | res->flags = IORESOURCE_BUSY; | |
1021 | res->desc = IORES_DESC_NONE; | |
1022 | ||
1023 | while (1) { | |
1024 | ||
1025 | conflict = __request_resource(parent, res); | |
1026 | if (!conflict) { | |
1027 | if (!next_res) | |
1028 | break; | |
1029 | res = next_res; | |
1030 | next_res = NULL; | |
1031 | continue; | |
1032 | } | |
1033 | ||
1034 | /* conflict covered whole area */ | |
1035 | if (conflict->start <= res->start && | |
1036 | conflict->end >= res->end) { | |
1037 | free_resource(res); | |
1038 | WARN_ON(next_res); | |
1039 | break; | |
1040 | } | |
1041 | ||
1042 | /* failed, split and try again */ | |
1043 | if (conflict->start > res->start) { | |
1044 | end = res->end; | |
1045 | res->end = conflict->start - 1; | |
1046 | if (conflict->end < end) { | |
1047 | next_res = alloc_resource(GFP_ATOMIC); | |
1048 | if (!next_res) { | |
1049 | free_resource(res); | |
1050 | break; | |
1051 | } | |
1052 | next_res->name = name; | |
1053 | next_res->start = conflict->end + 1; | |
1054 | next_res->end = end; | |
1055 | next_res->flags = IORESOURCE_BUSY; | |
1056 | next_res->desc = IORES_DESC_NONE; | |
1057 | } | |
1058 | } else { | |
1059 | res->start = conflict->end + 1; | |
1060 | } | |
1061 | } | |
1062 | ||
1063 | } | |
1064 | ||
1065 | void __init reserve_region_with_split(struct resource *root, | |
1066 | resource_size_t start, resource_size_t end, | |
1067 | const char *name) | |
1068 | { | |
1069 | int abort = 0; | |
1070 | ||
1071 | write_lock(&resource_lock); | |
1072 | if (root->start > start || root->end < end) { | |
1073 | pr_err("requested range [0x%llx-0x%llx] not in root %pr\n", | |
1074 | (unsigned long long)start, (unsigned long long)end, | |
1075 | root); | |
1076 | if (start > root->end || end < root->start) | |
1077 | abort = 1; | |
1078 | else { | |
1079 | if (end > root->end) | |
1080 | end = root->end; | |
1081 | if (start < root->start) | |
1082 | start = root->start; | |
1083 | pr_err("fixing request to [0x%llx-0x%llx]\n", | |
1084 | (unsigned long long)start, | |
1085 | (unsigned long long)end); | |
1086 | } | |
1087 | dump_stack(); | |
1088 | } | |
1089 | if (!abort) | |
1090 | __reserve_region_with_split(root, start, end, name); | |
1091 | write_unlock(&resource_lock); | |
1092 | } | |
1093 | ||
1094 | /** | |
1095 | * resource_alignment - calculate resource's alignment | |
1096 | * @res: resource pointer | |
1097 | * | |
1098 | * Returns alignment on success, 0 (invalid alignment) on failure. | |
1099 | */ | |
1100 | resource_size_t resource_alignment(struct resource *res) | |
1101 | { | |
1102 | switch (res->flags & (IORESOURCE_SIZEALIGN | IORESOURCE_STARTALIGN)) { | |
1103 | case IORESOURCE_SIZEALIGN: | |
1104 | return resource_size(res); | |
1105 | case IORESOURCE_STARTALIGN: | |
1106 | return res->start; | |
1107 | default: | |
1108 | return 0; | |
1109 | } | |
1110 | } | |
1111 | ||
1112 | /* | |
1113 | * This is compatibility stuff for IO resources. | |
1114 | * | |
1115 | * Note how this, unlike the above, knows about | |
1116 | * the IO flag meanings (busy etc). | |
1117 | * | |
1118 | * request_region creates a new busy region. | |
1119 | * | |
1120 | * release_region releases a matching busy region. | |
1121 | */ | |
1122 | ||
1123 | static DECLARE_WAIT_QUEUE_HEAD(muxed_resource_wait); | |
1124 | ||
1125 | /** | |
1126 | * __request_region - create a new busy resource region | |
1127 | * @parent: parent resource descriptor | |
1128 | * @start: resource start address | |
1129 | * @n: resource region size | |
1130 | * @name: reserving caller's ID string | |
1131 | * @flags: IO resource flags | |
1132 | */ | |
1133 | struct resource * __request_region(struct resource *parent, | |
1134 | resource_size_t start, resource_size_t n, | |
1135 | const char *name, int flags) | |
1136 | { | |
1137 | DECLARE_WAITQUEUE(wait, current); | |
1138 | struct resource *res = alloc_resource(GFP_KERNEL); | |
1139 | ||
1140 | if (!res) | |
1141 | return NULL; | |
1142 | ||
1143 | res->name = name; | |
1144 | res->start = start; | |
1145 | res->end = start + n - 1; | |
1146 | ||
1147 | write_lock(&resource_lock); | |
1148 | ||
1149 | for (;;) { | |
1150 | struct resource *conflict; | |
1151 | ||
1152 | res->flags = resource_type(parent) | resource_ext_type(parent); | |
1153 | res->flags |= IORESOURCE_BUSY | flags; | |
1154 | res->desc = parent->desc; | |
1155 | ||
1156 | conflict = __request_resource(parent, res); | |
1157 | if (!conflict) | |
1158 | break; | |
1159 | if (conflict != parent) { | |
1160 | if (!(conflict->flags & IORESOURCE_BUSY)) { | |
1161 | parent = conflict; | |
1162 | continue; | |
1163 | } | |
1164 | } | |
1165 | if (conflict->flags & flags & IORESOURCE_MUXED) { | |
1166 | add_wait_queue(&muxed_resource_wait, &wait); | |
1167 | write_unlock(&resource_lock); | |
1168 | set_current_state(TASK_UNINTERRUPTIBLE); | |
1169 | schedule(); | |
1170 | remove_wait_queue(&muxed_resource_wait, &wait); | |
1171 | write_lock(&resource_lock); | |
1172 | continue; | |
1173 | } | |
1174 | /* Uhhuh, that didn't work out.. */ | |
1175 | free_resource(res); | |
1176 | res = NULL; | |
1177 | break; | |
1178 | } | |
1179 | write_unlock(&resource_lock); | |
1180 | return res; | |
1181 | } | |
1182 | EXPORT_SYMBOL(__request_region); | |
1183 | ||
1184 | /** | |
1185 | * __release_region - release a previously reserved resource region | |
1186 | * @parent: parent resource descriptor | |
1187 | * @start: resource start address | |
1188 | * @n: resource region size | |
1189 | * | |
1190 | * The described resource region must match a currently busy region. | |
1191 | */ | |
1192 | void __release_region(struct resource *parent, resource_size_t start, | |
1193 | resource_size_t n) | |
1194 | { | |
1195 | struct resource **p; | |
1196 | resource_size_t end; | |
1197 | ||
1198 | p = &parent->child; | |
1199 | end = start + n - 1; | |
1200 | ||
1201 | write_lock(&resource_lock); | |
1202 | ||
1203 | for (;;) { | |
1204 | struct resource *res = *p; | |
1205 | ||
1206 | if (!res) | |
1207 | break; | |
1208 | if (res->start <= start && res->end >= end) { | |
1209 | if (!(res->flags & IORESOURCE_BUSY)) { | |
1210 | p = &res->child; | |
1211 | continue; | |
1212 | } | |
1213 | if (res->start != start || res->end != end) | |
1214 | break; | |
1215 | *p = res->sibling; | |
1216 | write_unlock(&resource_lock); | |
1217 | if (res->flags & IORESOURCE_MUXED) | |
1218 | wake_up(&muxed_resource_wait); | |
1219 | free_resource(res); | |
1220 | return; | |
1221 | } | |
1222 | p = &res->sibling; | |
1223 | } | |
1224 | ||
1225 | write_unlock(&resource_lock); | |
1226 | ||
1227 | printk(KERN_WARNING "Trying to free nonexistent resource " | |
1228 | "<%016llx-%016llx>\n", (unsigned long long)start, | |
1229 | (unsigned long long)end); | |
1230 | } | |
1231 | EXPORT_SYMBOL(__release_region); | |
1232 | ||
1233 | #ifdef CONFIG_MEMORY_HOTREMOVE | |
1234 | /** | |
1235 | * release_mem_region_adjustable - release a previously reserved memory region | |
1236 | * @parent: parent resource descriptor | |
1237 | * @start: resource start address | |
1238 | * @size: resource region size | |
1239 | * | |
1240 | * This interface is intended for memory hot-delete. The requested region | |
1241 | * is released from a currently busy memory resource. The requested region | |
1242 | * must either match exactly or fit into a single busy resource entry. In | |
1243 | * the latter case, the remaining resource is adjusted accordingly. | |
1244 | * Existing children of the busy memory resource must be immutable in the | |
1245 | * request. | |
1246 | * | |
1247 | * Note: | |
1248 | * - Additional release conditions, such as overlapping region, can be | |
1249 | * supported after they are confirmed as valid cases. | |
1250 | * - When a busy memory resource gets split into two entries, the code | |
1251 | * assumes that all children remain in the lower address entry for | |
1252 | * simplicity. Enhance this logic when necessary. | |
1253 | */ | |
1254 | int release_mem_region_adjustable(struct resource *parent, | |
1255 | resource_size_t start, resource_size_t size) | |
1256 | { | |
1257 | struct resource **p; | |
1258 | struct resource *res; | |
1259 | struct resource *new_res; | |
1260 | resource_size_t end; | |
1261 | int ret = -EINVAL; | |
1262 | ||
1263 | end = start + size - 1; | |
1264 | if ((start < parent->start) || (end > parent->end)) | |
1265 | return ret; | |
1266 | ||
1267 | /* The alloc_resource() result gets checked later */ | |
1268 | new_res = alloc_resource(GFP_KERNEL); | |
1269 | ||
1270 | p = &parent->child; | |
1271 | write_lock(&resource_lock); | |
1272 | ||
1273 | while ((res = *p)) { | |
1274 | if (res->start >= end) | |
1275 | break; | |
1276 | ||
1277 | /* look for the next resource if it does not fit into */ | |
1278 | if (res->start > start || res->end < end) { | |
1279 | p = &res->sibling; | |
1280 | continue; | |
1281 | } | |
1282 | ||
1283 | if (!(res->flags & IORESOURCE_MEM)) | |
1284 | break; | |
1285 | ||
1286 | if (!(res->flags & IORESOURCE_BUSY)) { | |
1287 | p = &res->child; | |
1288 | continue; | |
1289 | } | |
1290 | ||
1291 | /* found the target resource; let's adjust accordingly */ | |
1292 | if (res->start == start && res->end == end) { | |
1293 | /* free the whole entry */ | |
1294 | *p = res->sibling; | |
1295 | free_resource(res); | |
1296 | ret = 0; | |
1297 | } else if (res->start == start && res->end != end) { | |
1298 | /* adjust the start */ | |
1299 | ret = __adjust_resource(res, end + 1, | |
1300 | res->end - end); | |
1301 | } else if (res->start != start && res->end == end) { | |
1302 | /* adjust the end */ | |
1303 | ret = __adjust_resource(res, res->start, | |
1304 | start - res->start); | |
1305 | } else { | |
1306 | /* split into two entries */ | |
1307 | if (!new_res) { | |
1308 | ret = -ENOMEM; | |
1309 | break; | |
1310 | } | |
1311 | new_res->name = res->name; | |
1312 | new_res->start = end + 1; | |
1313 | new_res->end = res->end; | |
1314 | new_res->flags = res->flags; | |
1315 | new_res->desc = res->desc; | |
1316 | new_res->parent = res->parent; | |
1317 | new_res->sibling = res->sibling; | |
1318 | new_res->child = NULL; | |
1319 | ||
1320 | ret = __adjust_resource(res, res->start, | |
1321 | start - res->start); | |
1322 | if (ret) | |
1323 | break; | |
1324 | res->sibling = new_res; | |
1325 | new_res = NULL; | |
1326 | } | |
1327 | ||
1328 | break; | |
1329 | } | |
1330 | ||
1331 | write_unlock(&resource_lock); | |
1332 | free_resource(new_res); | |
1333 | return ret; | |
1334 | } | |
1335 | #endif /* CONFIG_MEMORY_HOTREMOVE */ | |
1336 | ||
1337 | /* | |
1338 | * Managed region resource | |
1339 | */ | |
1340 | static void devm_resource_release(struct device *dev, void *ptr) | |
1341 | { | |
1342 | struct resource **r = ptr; | |
1343 | ||
1344 | release_resource(*r); | |
1345 | } | |
1346 | ||
1347 | /** | |
1348 | * devm_request_resource() - request and reserve an I/O or memory resource | |
1349 | * @dev: device for which to request the resource | |
1350 | * @root: root of the resource tree from which to request the resource | |
1351 | * @new: descriptor of the resource to request | |
1352 | * | |
1353 | * This is a device-managed version of request_resource(). There is usually | |
1354 | * no need to release resources requested by this function explicitly since | |
1355 | * that will be taken care of when the device is unbound from its driver. | |
1356 | * If for some reason the resource needs to be released explicitly, because | |
1357 | * of ordering issues for example, drivers must call devm_release_resource() | |
1358 | * rather than the regular release_resource(). | |
1359 | * | |
1360 | * When a conflict is detected between any existing resources and the newly | |
1361 | * requested resource, an error message will be printed. | |
1362 | * | |
1363 | * Returns 0 on success or a negative error code on failure. | |
1364 | */ | |
1365 | int devm_request_resource(struct device *dev, struct resource *root, | |
1366 | struct resource *new) | |
1367 | { | |
1368 | struct resource *conflict, **ptr; | |
1369 | ||
1370 | ptr = devres_alloc(devm_resource_release, sizeof(*ptr), GFP_KERNEL); | |
1371 | if (!ptr) | |
1372 | return -ENOMEM; | |
1373 | ||
1374 | *ptr = new; | |
1375 | ||
1376 | conflict = request_resource_conflict(root, new); | |
1377 | if (conflict) { | |
1378 | dev_err(dev, "resource collision: %pR conflicts with %s %pR\n", | |
1379 | new, conflict->name, conflict); | |
1380 | devres_free(ptr); | |
1381 | return -EBUSY; | |
1382 | } | |
1383 | ||
1384 | devres_add(dev, ptr); | |
1385 | return 0; | |
1386 | } | |
1387 | EXPORT_SYMBOL(devm_request_resource); | |
1388 | ||
1389 | static int devm_resource_match(struct device *dev, void *res, void *data) | |
1390 | { | |
1391 | struct resource **ptr = res; | |
1392 | ||
1393 | return *ptr == data; | |
1394 | } | |
1395 | ||
1396 | /** | |
1397 | * devm_release_resource() - release a previously requested resource | |
1398 | * @dev: device for which to release the resource | |
1399 | * @new: descriptor of the resource to release | |
1400 | * | |
1401 | * Releases a resource previously requested using devm_request_resource(). | |
1402 | */ | |
1403 | void devm_release_resource(struct device *dev, struct resource *new) | |
1404 | { | |
1405 | WARN_ON(devres_release(dev, devm_resource_release, devm_resource_match, | |
1406 | new)); | |
1407 | } | |
1408 | EXPORT_SYMBOL(devm_release_resource); | |
1409 | ||
1410 | struct region_devres { | |
1411 | struct resource *parent; | |
1412 | resource_size_t start; | |
1413 | resource_size_t n; | |
1414 | }; | |
1415 | ||
1416 | static void devm_region_release(struct device *dev, void *res) | |
1417 | { | |
1418 | struct region_devres *this = res; | |
1419 | ||
1420 | __release_region(this->parent, this->start, this->n); | |
1421 | } | |
1422 | ||
1423 | static int devm_region_match(struct device *dev, void *res, void *match_data) | |
1424 | { | |
1425 | struct region_devres *this = res, *match = match_data; | |
1426 | ||
1427 | return this->parent == match->parent && | |
1428 | this->start == match->start && this->n == match->n; | |
1429 | } | |
1430 | ||
1431 | struct resource * __devm_request_region(struct device *dev, | |
1432 | struct resource *parent, resource_size_t start, | |
1433 | resource_size_t n, const char *name) | |
1434 | { | |
1435 | struct region_devres *dr = NULL; | |
1436 | struct resource *res; | |
1437 | ||
1438 | dr = devres_alloc(devm_region_release, sizeof(struct region_devres), | |
1439 | GFP_KERNEL); | |
1440 | if (!dr) | |
1441 | return NULL; | |
1442 | ||
1443 | dr->parent = parent; | |
1444 | dr->start = start; | |
1445 | dr->n = n; | |
1446 | ||
1447 | res = __request_region(parent, start, n, name, 0); | |
1448 | if (res) | |
1449 | devres_add(dev, dr); | |
1450 | else | |
1451 | devres_free(dr); | |
1452 | ||
1453 | return res; | |
1454 | } | |
1455 | EXPORT_SYMBOL(__devm_request_region); | |
1456 | ||
1457 | void __devm_release_region(struct device *dev, struct resource *parent, | |
1458 | resource_size_t start, resource_size_t n) | |
1459 | { | |
1460 | struct region_devres match_data = { parent, start, n }; | |
1461 | ||
1462 | __release_region(parent, start, n); | |
1463 | WARN_ON(devres_destroy(dev, devm_region_release, devm_region_match, | |
1464 | &match_data)); | |
1465 | } | |
1466 | EXPORT_SYMBOL(__devm_release_region); | |
1467 | ||
1468 | /* | |
1469 | * Called from init/main.c to reserve IO ports. | |
1470 | */ | |
1471 | #define MAXRESERVE 4 | |
1472 | static int __init reserve_setup(char *str) | |
1473 | { | |
1474 | static int reserved; | |
1475 | static struct resource reserve[MAXRESERVE]; | |
1476 | ||
1477 | for (;;) { | |
1478 | unsigned int io_start, io_num; | |
1479 | int x = reserved; | |
1480 | ||
1481 | if (get_option (&str, &io_start) != 2) | |
1482 | break; | |
1483 | if (get_option (&str, &io_num) == 0) | |
1484 | break; | |
1485 | if (x < MAXRESERVE) { | |
1486 | struct resource *res = reserve + x; | |
1487 | res->name = "reserved"; | |
1488 | res->start = io_start; | |
1489 | res->end = io_start + io_num - 1; | |
1490 | res->flags = IORESOURCE_BUSY; | |
1491 | res->desc = IORES_DESC_NONE; | |
1492 | res->child = NULL; | |
1493 | if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, res) == 0) | |
1494 | reserved = x+1; | |
1495 | } | |
1496 | } | |
1497 | return 1; | |
1498 | } | |
1499 | ||
1500 | __setup("reserve=", reserve_setup); | |
1501 | ||
1502 | /* | |
1503 | * Check if the requested addr and size spans more than any slot in the | |
1504 | * iomem resource tree. | |
1505 | */ | |
1506 | int iomem_map_sanity_check(resource_size_t addr, unsigned long size) | |
1507 | { | |
1508 | struct resource *p = &iomem_resource; | |
1509 | int err = 0; | |
1510 | loff_t l; | |
1511 | ||
1512 | read_lock(&resource_lock); | |
1513 | for (p = p->child; p ; p = r_next(NULL, p, &l)) { | |
1514 | /* | |
1515 | * We can probably skip the resources without | |
1516 | * IORESOURCE_IO attribute? | |
1517 | */ | |
1518 | if (p->start >= addr + size) | |
1519 | continue; | |
1520 | if (p->end < addr) | |
1521 | continue; | |
1522 | if (PFN_DOWN(p->start) <= PFN_DOWN(addr) && | |
1523 | PFN_DOWN(p->end) >= PFN_DOWN(addr + size - 1)) | |
1524 | continue; | |
1525 | /* | |
1526 | * if a resource is "BUSY", it's not a hardware resource | |
1527 | * but a driver mapping of such a resource; we don't want | |
1528 | * to warn for those; some drivers legitimately map only | |
1529 | * partial hardware resources. (example: vesafb) | |
1530 | */ | |
1531 | if (p->flags & IORESOURCE_BUSY) | |
1532 | continue; | |
1533 | ||
1534 | printk(KERN_WARNING "resource sanity check: requesting [mem %#010llx-%#010llx], which spans more than %s %pR\n", | |
1535 | (unsigned long long)addr, | |
1536 | (unsigned long long)(addr + size - 1), | |
1537 | p->name, p); | |
1538 | err = -1; | |
1539 | break; | |
1540 | } | |
1541 | read_unlock(&resource_lock); | |
1542 | ||
1543 | return err; | |
1544 | } | |
1545 | ||
1546 | #ifdef CONFIG_STRICT_DEVMEM | |
1547 | static int strict_iomem_checks = 1; | |
1548 | #else | |
1549 | static int strict_iomem_checks; | |
1550 | #endif | |
1551 | ||
1552 | /* | |
1553 | * check if an address is reserved in the iomem resource tree | |
1554 | * returns 1 if reserved, 0 if not reserved. | |
1555 | */ | |
1556 | int iomem_is_exclusive(u64 addr) | |
1557 | { | |
1558 | struct resource *p = &iomem_resource; | |
1559 | int err = 0; | |
1560 | loff_t l; | |
1561 | int size = PAGE_SIZE; | |
1562 | ||
1563 | if (!strict_iomem_checks) | |
1564 | return 0; | |
1565 | ||
1566 | addr = addr & PAGE_MASK; | |
1567 | ||
1568 | read_lock(&resource_lock); | |
1569 | for (p = p->child; p ; p = r_next(NULL, p, &l)) { | |
1570 | /* | |
1571 | * We can probably skip the resources without | |
1572 | * IORESOURCE_IO attribute? | |
1573 | */ | |
1574 | if (p->start >= addr + size) | |
1575 | break; | |
1576 | if (p->end < addr) | |
1577 | continue; | |
1578 | /* | |
1579 | * A resource is exclusive if IORESOURCE_EXCLUSIVE is set | |
1580 | * or CONFIG_IO_STRICT_DEVMEM is enabled and the | |
1581 | * resource is busy. | |
1582 | */ | |
1583 | if ((p->flags & IORESOURCE_BUSY) == 0) | |
1584 | continue; | |
1585 | if (IS_ENABLED(CONFIG_IO_STRICT_DEVMEM) | |
1586 | || p->flags & IORESOURCE_EXCLUSIVE) { | |
1587 | err = 1; | |
1588 | break; | |
1589 | } | |
1590 | } | |
1591 | read_unlock(&resource_lock); | |
1592 | ||
1593 | return err; | |
1594 | } | |
1595 | ||
1596 | struct resource_entry *resource_list_create_entry(struct resource *res, | |
1597 | size_t extra_size) | |
1598 | { | |
1599 | struct resource_entry *entry; | |
1600 | ||
1601 | entry = kzalloc(sizeof(*entry) + extra_size, GFP_KERNEL); | |
1602 | if (entry) { | |
1603 | INIT_LIST_HEAD(&entry->node); | |
1604 | entry->res = res ? res : &entry->__res; | |
1605 | } | |
1606 | ||
1607 | return entry; | |
1608 | } | |
1609 | EXPORT_SYMBOL(resource_list_create_entry); | |
1610 | ||
1611 | void resource_list_free(struct list_head *head) | |
1612 | { | |
1613 | struct resource_entry *entry, *tmp; | |
1614 | ||
1615 | list_for_each_entry_safe(entry, tmp, head, node) | |
1616 | resource_list_destroy_entry(entry); | |
1617 | } | |
1618 | EXPORT_SYMBOL(resource_list_free); | |
1619 | ||
1620 | static int __init strict_iomem(char *str) | |
1621 | { | |
1622 | if (strstr(str, "relaxed")) | |
1623 | strict_iomem_checks = 0; | |
1624 | if (strstr(str, "strict")) | |
1625 | strict_iomem_checks = 1; | |
1626 | return 1; | |
1627 | } | |
1628 | ||
1629 | __setup("iomem=", strict_iomem); |