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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
Octavian Purdila65fed8f2012-07-30 14:42:58 -070010#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11
Paul Gortmaker9984de12011-05-23 14:51:41 -040012#include <linux/export.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070013#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>
Alan Cox8b6d0432010-03-29 19:38:00 +020020#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#include <linux/seq_file.h>
Tejun Heo9ac78492007-01-20 16:00:26 +090022#include <linux/device.h>
Suresh Siddhad68612b2008-10-28 11:45:42 -070023#include <linux/pfn.h>
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -070024#include <linux/mm.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070025#include <asm/io.h>
26
27
28struct resource ioport_resource = {
29 .name = "PCI IO",
Greg Kroah-Hartman6550e072006-06-12 17:11:31 -070030 .start = 0,
Linus Torvalds1da177e2005-04-16 15:20:36 -070031 .end = IO_SPACE_LIMIT,
32 .flags = IORESOURCE_IO,
33};
Linus Torvalds1da177e2005-04-16 15:20:36 -070034EXPORT_SYMBOL(ioport_resource);
35
36struct resource iomem_resource = {
37 .name = "PCI mem",
Greg Kroah-Hartman6550e072006-06-12 17:11:31 -070038 .start = 0,
39 .end = -1,
Linus Torvalds1da177e2005-04-16 15:20:36 -070040 .flags = IORESOURCE_MEM,
41};
Linus Torvalds1da177e2005-04-16 15:20:36 -070042EXPORT_SYMBOL(iomem_resource);
43
Ram Pai23c570a2011-07-05 23:44:30 -070044/* constraints to be met while allocating resources */
45struct resource_constraint {
46 resource_size_t min, max, align;
47 resource_size_t (*alignf)(void *, const struct resource *,
48 resource_size_t, resource_size_t);
49 void *alignf_data;
50};
51
Linus Torvalds1da177e2005-04-16 15:20:36 -070052static DEFINE_RWLOCK(resource_lock);
53
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -070054/*
55 * For memory hotplug, there is no way to free resource entries allocated
56 * by boot mem after the system is up. So for reusing the resource entry
57 * we need to remember the resource.
58 */
59static struct resource *bootmem_resource_free;
60static DEFINE_SPINLOCK(bootmem_resource_lock);
61
Linus Torvalds1da177e2005-04-16 15:20:36 -070062static void *r_next(struct seq_file *m, void *v, loff_t *pos)
63{
64 struct resource *p = v;
65 (*pos)++;
66 if (p->child)
67 return p->child;
68 while (!p->sibling && p->parent)
69 p = p->parent;
70 return p->sibling;
71}
72
Ingo Molnar13eb8372008-09-26 10:10:12 +020073#ifdef CONFIG_PROC_FS
74
75enum { MAX_IORES_LEVEL = 5 };
76
Linus Torvalds1da177e2005-04-16 15:20:36 -070077static void *r_start(struct seq_file *m, loff_t *pos)
78 __acquires(resource_lock)
79{
80 struct resource *p = m->private;
81 loff_t l = 0;
82 read_lock(&resource_lock);
83 for (p = p->child; p && l < *pos; p = r_next(m, p, &l))
84 ;
85 return p;
86}
87
88static void r_stop(struct seq_file *m, void *v)
89 __releases(resource_lock)
90{
91 read_unlock(&resource_lock);
92}
93
94static int r_show(struct seq_file *m, void *v)
95{
96 struct resource *root = m->private;
97 struct resource *r = v, *p;
98 int width = root->end < 0x10000 ? 4 : 8;
99 int depth;
100
101 for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent)
102 if (p->parent == root)
103 break;
Greg Kroah-Hartman685143ac2006-06-12 15:18:31 -0700104 seq_printf(m, "%*s%0*llx-%0*llx : %s\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105 depth * 2, "",
Greg Kroah-Hartman685143ac2006-06-12 15:18:31 -0700106 width, (unsigned long long) r->start,
107 width, (unsigned long long) r->end,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 r->name ? r->name : "<BAD>");
109 return 0;
110}
111
Helge Deller15ad7cd2006-12-06 20:40:36 -0800112static const struct seq_operations resource_op = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113 .start = r_start,
114 .next = r_next,
115 .stop = r_stop,
116 .show = r_show,
117};
118
119static int ioports_open(struct inode *inode, struct file *file)
120{
121 int res = seq_open(file, &resource_op);
122 if (!res) {
123 struct seq_file *m = file->private_data;
124 m->private = &ioport_resource;
125 }
126 return res;
127}
128
129static int iomem_open(struct inode *inode, struct file *file)
130{
131 int res = seq_open(file, &resource_op);
132 if (!res) {
133 struct seq_file *m = file->private_data;
134 m->private = &iomem_resource;
135 }
136 return res;
137}
138
Helge Deller15ad7cd2006-12-06 20:40:36 -0800139static const struct file_operations proc_ioports_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140 .open = ioports_open,
141 .read = seq_read,
142 .llseek = seq_lseek,
143 .release = seq_release,
144};
145
Helge Deller15ad7cd2006-12-06 20:40:36 -0800146static const struct file_operations proc_iomem_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147 .open = iomem_open,
148 .read = seq_read,
149 .llseek = seq_lseek,
150 .release = seq_release,
151};
152
153static int __init ioresources_init(void)
154{
Denis V. Lunevc33fff02008-04-29 01:02:31 -0700155 proc_create("ioports", 0, NULL, &proc_ioports_operations);
156 proc_create("iomem", 0, NULL, &proc_iomem_operations);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 return 0;
158}
159__initcall(ioresources_init);
160
161#endif /* CONFIG_PROC_FS */
162
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -0700163static void free_resource(struct resource *res)
164{
165 if (!res)
166 return;
167
168 if (!PageSlab(virt_to_head_page(res))) {
169 spin_lock(&bootmem_resource_lock);
170 res->sibling = bootmem_resource_free;
171 bootmem_resource_free = res;
172 spin_unlock(&bootmem_resource_lock);
173 } else {
174 kfree(res);
175 }
176}
177
178static struct resource *alloc_resource(gfp_t flags)
179{
180 struct resource *res = NULL;
181
182 spin_lock(&bootmem_resource_lock);
183 if (bootmem_resource_free) {
184 res = bootmem_resource_free;
185 bootmem_resource_free = res->sibling;
186 }
187 spin_unlock(&bootmem_resource_lock);
188
189 if (res)
190 memset(res, 0, sizeof(struct resource));
191 else
192 res = kzalloc(sizeof(struct resource), flags);
193
194 return res;
195}
196
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197/* Return the conflict entry if you can't request it */
198static struct resource * __request_resource(struct resource *root, struct resource *new)
199{
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700200 resource_size_t start = new->start;
201 resource_size_t end = new->end;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202 struct resource *tmp, **p;
203
204 if (end < start)
205 return root;
206 if (start < root->start)
207 return root;
208 if (end > root->end)
209 return root;
210 p = &root->child;
211 for (;;) {
212 tmp = *p;
213 if (!tmp || tmp->start > end) {
214 new->sibling = tmp;
215 *p = new;
216 new->parent = root;
217 return NULL;
218 }
219 p = &tmp->sibling;
220 if (tmp->end < start)
221 continue;
222 return tmp;
223 }
224}
225
226static int __release_resource(struct resource *old)
227{
228 struct resource *tmp, **p;
229
230 p = &old->parent->child;
231 for (;;) {
232 tmp = *p;
233 if (!tmp)
234 break;
235 if (tmp == old) {
236 *p = tmp->sibling;
237 old->parent = NULL;
238 return 0;
239 }
240 p = &tmp->sibling;
241 }
242 return -EINVAL;
243}
244
Yinghai Lu5eeec0e2009-12-22 15:02:22 -0800245static void __release_child_resources(struct resource *r)
246{
247 struct resource *tmp, *p;
248 resource_size_t size;
249
250 p = r->child;
251 r->child = NULL;
252 while (p) {
253 tmp = p;
254 p = p->sibling;
255
256 tmp->parent = NULL;
257 tmp->sibling = NULL;
258 __release_child_resources(tmp);
259
260 printk(KERN_DEBUG "release child resource %pR\n", tmp);
261 /* need to restore size, and keep flags */
262 size = resource_size(tmp);
263 tmp->start = 0;
264 tmp->end = size - 1;
265 }
266}
267
268void release_child_resources(struct resource *r)
269{
270 write_lock(&resource_lock);
271 __release_child_resources(r);
272 write_unlock(&resource_lock);
273}
274
Randy Dunlape1ca66d1b2006-10-03 01:13:51 -0700275/**
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700276 * request_resource_conflict - request and reserve an I/O or memory resource
277 * @root: root resource descriptor
278 * @new: resource descriptor desired by caller
279 *
280 * Returns 0 for success, conflict resource on error.
281 */
282struct resource *request_resource_conflict(struct resource *root, struct resource *new)
283{
284 struct resource *conflict;
285
286 write_lock(&resource_lock);
287 conflict = __request_resource(root, new);
288 write_unlock(&resource_lock);
289 return conflict;
290}
291
292/**
Randy Dunlape1ca66d1b2006-10-03 01:13:51 -0700293 * request_resource - request and reserve an I/O or memory resource
294 * @root: root resource descriptor
295 * @new: resource descriptor desired by caller
296 *
297 * Returns 0 for success, negative error code on error.
298 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299int request_resource(struct resource *root, struct resource *new)
300{
301 struct resource *conflict;
302
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700303 conflict = request_resource_conflict(root, new);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 return conflict ? -EBUSY : 0;
305}
306
307EXPORT_SYMBOL(request_resource);
308
Randy Dunlape1ca66d1b2006-10-03 01:13:51 -0700309/**
Randy Dunlape1ca66d1b2006-10-03 01:13:51 -0700310 * release_resource - release a previously reserved resource
311 * @old: resource pointer
312 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313int release_resource(struct resource *old)
314{
315 int retval;
316
317 write_lock(&resource_lock);
318 retval = __release_resource(old);
319 write_unlock(&resource_lock);
320 return retval;
321}
322
323EXPORT_SYMBOL(release_resource);
324
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700325#if !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700326/*
327 * Finds the lowest memory reosurce exists within [res->start.res->end)
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700328 * the caller must specify res->start, res->end, res->flags and "name".
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700329 * If found, returns 0, res is overwritten, if not found, returns -1.
330 */
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700331static int find_next_system_ram(struct resource *res, char *name)
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700332{
333 resource_size_t start, end;
334 struct resource *p;
335
336 BUG_ON(!res);
337
338 start = res->start;
339 end = res->end;
KAMEZAWA Hiroyuki58c1b5b2006-08-05 12:15:01 -0700340 BUG_ON(start >= end);
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700341
342 read_lock(&resource_lock);
343 for (p = iomem_resource.child; p ; p = p->sibling) {
344 /* system ram is just marked as IORESOURCE_MEM */
345 if (p->flags != res->flags)
346 continue;
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700347 if (name && strcmp(p->name, name))
348 continue;
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700349 if (p->start > end) {
350 p = NULL;
351 break;
352 }
KAMEZAWA Hiroyuki58c1b5b2006-08-05 12:15:01 -0700353 if ((p->end >= start) && (p->start < end))
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700354 break;
355 }
356 read_unlock(&resource_lock);
357 if (!p)
358 return -1;
359 /* copy data */
KAMEZAWA Hiroyuki0f04ab52006-08-05 12:14:59 -0700360 if (res->start < p->start)
361 res->start = p->start;
362 if (res->end > p->end)
363 res->end = p->end;
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700364 return 0;
365}
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700366
367/*
368 * This function calls callback against all memory range of "System RAM"
369 * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY.
370 * Now, this function is only for "System RAM".
371 */
372int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
373 void *arg, int (*func)(unsigned long, unsigned long, void *))
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700374{
375 struct resource res;
Wu Fengguang37b99dd2010-03-01 21:55:51 +0800376 unsigned long pfn, end_pfn;
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700377 u64 orig_end;
378 int ret = -1;
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700379
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700380 res.start = (u64) start_pfn << PAGE_SHIFT;
381 res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1;
Yasunori Goto887c3cb2007-11-14 16:59:20 -0800382 res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700383 orig_end = res.end;
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700384 while ((res.start < res.end) &&
385 (find_next_system_ram(&res, "System RAM") >= 0)) {
Wu Fengguang37b99dd2010-03-01 21:55:51 +0800386 pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT;
387 end_pfn = (res.end + 1) >> PAGE_SHIFT;
388 if (end_pfn > pfn)
H. Peter Anvinf4149662010-03-02 11:21:09 -0800389 ret = (*func)(pfn, end_pfn - pfn, arg);
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700390 if (ret)
391 break;
392 res.start = res.end + 1;
393 res.end = orig_end;
394 }
395 return ret;
396}
397
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700398#endif
399
Wu Fengguang61ef2482010-01-22 16:16:19 +0800400static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg)
401{
402 return 1;
403}
404/*
405 * This generic page_is_ram() returns true if specified address is
406 * registered as "System RAM" in iomem_resource list.
407 */
Andrew Mortone5273002010-01-26 16:31:19 -0800408int __weak page_is_ram(unsigned long pfn)
Wu Fengguang61ef2482010-01-22 16:16:19 +0800409{
410 return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1;
411}
Chen Gongc5a13032013-06-06 15:20:51 -0700412EXPORT_SYMBOL_GPL(page_is_ram);
Wu Fengguang61ef2482010-01-22 16:16:19 +0800413
Bjorn Helgaasfcb11912010-12-16 10:38:46 -0700414void __weak arch_remove_reservations(struct resource *avail)
415{
416}
417
Bjorn Helgaasa9cea012010-10-26 15:41:13 -0600418static resource_size_t simple_align_resource(void *data,
419 const struct resource *avail,
420 resource_size_t size,
421 resource_size_t align)
422{
423 return avail->start;
424}
425
Bjorn Helgaas5d6b1fa2010-10-26 15:41:18 -0600426static void resource_clip(struct resource *res, resource_size_t min,
427 resource_size_t max)
428{
429 if (res->start < min)
430 res->start = min;
431 if (res->end > max)
432 res->end = max;
433}
434
Bjorn Helgaas6909ba12010-10-26 15:41:23 -0600435static bool resource_contains(struct resource *res1, struct resource *res2)
436{
437 return res1->start <= res2->start && res1->end >= res2->end;
438}
439
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440/*
Ram Pai23c570a2011-07-05 23:44:30 -0700441 * Find empty slot in the resource tree with the given range and
442 * alignment constraints
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443 */
Ram Pai23c570a2011-07-05 23:44:30 -0700444static int __find_resource(struct resource *root, struct resource *old,
445 struct resource *new,
446 resource_size_t size,
447 struct resource_constraint *constraint)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448{
449 struct resource *this = root->child;
Bjorn Helgaasa1862e32010-10-26 15:41:28 -0600450 struct resource tmp = *new, avail, alloc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451
Dominik Brodowski0e2c8b82009-12-20 10:50:02 +0100452 tmp.start = root->start;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453 /*
Bjorn Helgaasc0f5ac52010-12-16 10:38:41 -0700454 * Skip past an allocated resource that starts at 0, since the assignment
455 * of this->start - 1 to tmp->end below would cause an underflow.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456 */
Ram Pai23c570a2011-07-05 23:44:30 -0700457 if (this && this->start == root->start) {
458 tmp.start = (this == old) ? old->start : this->end + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459 this = this->sibling;
460 }
Bjorn Helgaasc0f5ac52010-12-16 10:38:41 -0700461 for(;;) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462 if (this)
Ram Pai23c570a2011-07-05 23:44:30 -0700463 tmp.end = (this == old) ? this->end : this->start - 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700464 else
Dominik Brodowski0e2c8b82009-12-20 10:50:02 +0100465 tmp.end = root->end;
Bjorn Helgaas5d6b1fa2010-10-26 15:41:18 -0600466
Ram Pai47ea91b2011-09-22 15:48:58 +0800467 if (tmp.end < tmp.start)
468 goto next;
469
Ram Pai23c570a2011-07-05 23:44:30 -0700470 resource_clip(&tmp, constraint->min, constraint->max);
Bjorn Helgaasfcb11912010-12-16 10:38:46 -0700471 arch_remove_reservations(&tmp);
Bjorn Helgaasa9cea012010-10-26 15:41:13 -0600472
Bjorn Helgaasa1862e32010-10-26 15:41:28 -0600473 /* Check for overflow after ALIGN() */
474 avail = *new;
Ram Pai23c570a2011-07-05 23:44:30 -0700475 avail.start = ALIGN(tmp.start, constraint->align);
Bjorn Helgaasa1862e32010-10-26 15:41:28 -0600476 avail.end = tmp.end;
477 if (avail.start >= tmp.start) {
Ram Pai23c570a2011-07-05 23:44:30 -0700478 alloc.start = constraint->alignf(constraint->alignf_data, &avail,
479 size, constraint->align);
Bjorn Helgaasa1862e32010-10-26 15:41:28 -0600480 alloc.end = alloc.start + size - 1;
481 if (resource_contains(&avail, &alloc)) {
482 new->start = alloc.start;
483 new->end = alloc.end;
484 return 0;
485 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486 }
Ram Pai47ea91b2011-09-22 15:48:58 +0800487
488next: if (!this || this->end == root->end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489 break;
Ram Pai47ea91b2011-09-22 15:48:58 +0800490
Ram Pai23c570a2011-07-05 23:44:30 -0700491 if (this != old)
492 tmp.start = this->end + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700493 this = this->sibling;
494 }
495 return -EBUSY;
496}
497
Ram Pai23c570a2011-07-05 23:44:30 -0700498/*
499 * Find empty slot in the resource tree given range and alignment.
500 */
501static int find_resource(struct resource *root, struct resource *new,
502 resource_size_t size,
503 struct resource_constraint *constraint)
504{
505 return __find_resource(root, NULL, new, size, constraint);
506}
507
Randy Dunlape1ca66d1b2006-10-03 01:13:51 -0700508/**
Ram Pai23c570a2011-07-05 23:44:30 -0700509 * reallocate_resource - allocate a slot in the resource tree given range & alignment.
510 * The resource will be relocated if the new size cannot be reallocated in the
511 * current location.
512 *
513 * @root: root resource descriptor
514 * @old: resource descriptor desired by caller
515 * @newsize: new size of the resource descriptor
516 * @constraint: the size and alignment constraints to be met.
517 */
518int reallocate_resource(struct resource *root, struct resource *old,
519 resource_size_t newsize,
520 struct resource_constraint *constraint)
521{
522 int err=0;
523 struct resource new = *old;
524 struct resource *conflict;
525
526 write_lock(&resource_lock);
527
528 if ((err = __find_resource(root, old, &new, newsize, constraint)))
529 goto out;
530
531 if (resource_contains(&new, old)) {
532 old->start = new.start;
533 old->end = new.end;
534 goto out;
535 }
536
537 if (old->child) {
538 err = -EBUSY;
539 goto out;
540 }
541
542 if (resource_contains(old, &new)) {
543 old->start = new.start;
544 old->end = new.end;
545 } else {
546 __release_resource(old);
547 *old = new;
548 conflict = __request_resource(root, old);
549 BUG_ON(conflict);
550 }
551out:
552 write_unlock(&resource_lock);
553 return err;
554}
555
556
557/**
558 * allocate_resource - allocate empty slot in the resource tree given range & alignment.
559 * The resource will be reallocated with a new size if it was already allocated
Randy Dunlape1ca66d1b2006-10-03 01:13:51 -0700560 * @root: root resource descriptor
561 * @new: resource descriptor desired by caller
562 * @size: requested resource region size
Wei Yangee5e5682012-05-31 16:26:05 -0700563 * @min: minimum boundary to allocate
564 * @max: maximum boundary to allocate
Randy Dunlape1ca66d1b2006-10-03 01:13:51 -0700565 * @align: alignment requested, in bytes
566 * @alignf: alignment function, optional, called if not NULL
567 * @alignf_data: arbitrary data to pass to the @alignf function
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568 */
569int allocate_resource(struct resource *root, struct resource *new,
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700570 resource_size_t size, resource_size_t min,
571 resource_size_t max, resource_size_t align,
Dominik Brodowskib26b2d42010-01-01 17:40:49 +0100572 resource_size_t (*alignf)(void *,
Dominik Brodowski3b7a17f2010-01-01 17:40:50 +0100573 const struct resource *,
Dominik Brodowskib26b2d42010-01-01 17:40:49 +0100574 resource_size_t,
575 resource_size_t),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576 void *alignf_data)
577{
578 int err;
Ram Pai23c570a2011-07-05 23:44:30 -0700579 struct resource_constraint constraint;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700580
Bjorn Helgaasa9cea012010-10-26 15:41:13 -0600581 if (!alignf)
582 alignf = simple_align_resource;
583
Ram Pai23c570a2011-07-05 23:44:30 -0700584 constraint.min = min;
585 constraint.max = max;
586 constraint.align = align;
587 constraint.alignf = alignf;
588 constraint.alignf_data = alignf_data;
589
590 if ( new->parent ) {
591 /* resource is already allocated, try reallocating with
592 the new constraints */
593 return reallocate_resource(root, new, size, &constraint);
594 }
595
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596 write_lock(&resource_lock);
Ram Pai23c570a2011-07-05 23:44:30 -0700597 err = find_resource(root, new, size, &constraint);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700598 if (err >= 0 && __request_resource(root, new))
599 err = -EBUSY;
600 write_unlock(&resource_lock);
601 return err;
602}
603
604EXPORT_SYMBOL(allocate_resource);
605
Geert Uytterhoeven1c388912011-05-07 20:53:16 +0200606/**
607 * lookup_resource - find an existing resource by a resource start address
608 * @root: root resource descriptor
609 * @start: resource start address
610 *
611 * Returns a pointer to the resource if found, NULL otherwise
612 */
613struct resource *lookup_resource(struct resource *root, resource_size_t start)
614{
615 struct resource *res;
616
617 read_lock(&resource_lock);
618 for (res = root->child; res; res = res->sibling) {
619 if (res->start == start)
620 break;
621 }
622 read_unlock(&resource_lock);
623
624 return res;
625}
626
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700627/*
628 * Insert a resource into the resource tree. If successful, return NULL,
629 * otherwise return the conflicting resource (compare to __request_resource())
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630 */
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700631static struct resource * __insert_resource(struct resource *parent, struct resource *new)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633 struct resource *first, *next;
634
Matthew Wilcoxd33b6fb2006-06-30 02:31:24 -0700635 for (;; parent = first) {
Matthew Wilcoxd33b6fb2006-06-30 02:31:24 -0700636 first = __request_resource(parent, new);
637 if (!first)
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700638 return first;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639
Matthew Wilcoxd33b6fb2006-06-30 02:31:24 -0700640 if (first == parent)
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700641 return first;
Huang Shijie5de1cb22010-10-27 15:34:52 -0700642 if (WARN_ON(first == new)) /* duplicated insertion */
643 return first;
Matthew Wilcoxd33b6fb2006-06-30 02:31:24 -0700644
645 if ((first->start > new->start) || (first->end < new->end))
646 break;
647 if ((first->start == new->start) && (first->end == new->end))
648 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700649 }
650
651 for (next = first; ; next = next->sibling) {
652 /* Partial overlap? Bad, and unfixable */
653 if (next->start < new->start || next->end > new->end)
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700654 return next;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700655 if (!next->sibling)
656 break;
657 if (next->sibling->start > new->end)
658 break;
659 }
660
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661 new->parent = parent;
662 new->sibling = next->sibling;
663 new->child = first;
664
665 next->sibling = NULL;
666 for (next = first; next; next = next->sibling)
667 next->parent = new;
668
669 if (parent->child == first) {
670 parent->child = new;
671 } else {
672 next = parent->child;
673 while (next->sibling != first)
674 next = next->sibling;
675 next->sibling = new;
676 }
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700677 return NULL;
678}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700679
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700680/**
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700681 * insert_resource_conflict - Inserts resource in the resource tree
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700682 * @parent: parent of the new resource
683 * @new: new resource to insert
684 *
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700685 * Returns 0 on success, conflict resource if the resource can't be inserted.
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700686 *
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700687 * This function is equivalent to request_resource_conflict when no conflict
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700688 * happens. If a conflict happens, and the conflicting resources
689 * entirely fit within the range of the new resource, then the new
690 * resource is inserted and the conflicting resources become children of
691 * the new resource.
692 */
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700693struct resource *insert_resource_conflict(struct resource *parent, struct resource *new)
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700694{
695 struct resource *conflict;
696
697 write_lock(&resource_lock);
698 conflict = __insert_resource(parent, new);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699 write_unlock(&resource_lock);
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700700 return conflict;
701}
702
703/**
704 * insert_resource - Inserts a resource in the resource tree
705 * @parent: parent of the new resource
706 * @new: new resource to insert
707 *
708 * Returns 0 on success, -EBUSY if the resource can't be inserted.
709 */
710int insert_resource(struct resource *parent, struct resource *new)
711{
712 struct resource *conflict;
713
714 conflict = insert_resource_conflict(parent, new);
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700715 return conflict ? -EBUSY : 0;
716}
717
718/**
719 * insert_resource_expand_to_fit - Insert a resource into the resource tree
Randy Dunlap6781f4a2008-08-31 20:31:55 -0700720 * @root: root resource descriptor
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700721 * @new: new resource to insert
722 *
723 * Insert a resource into the resource tree, possibly expanding it in order
724 * to make it encompass any conflicting resources.
725 */
726void insert_resource_expand_to_fit(struct resource *root, struct resource *new)
727{
728 if (new->parent)
729 return;
730
731 write_lock(&resource_lock);
732 for (;;) {
733 struct resource *conflict;
734
735 conflict = __insert_resource(root, new);
736 if (!conflict)
737 break;
738 if (conflict == root)
739 break;
740
741 /* Ok, expand resource to cover the conflict, then try again .. */
742 if (conflict->start < new->start)
743 new->start = conflict->start;
744 if (conflict->end > new->end)
745 new->end = conflict->end;
746
747 printk("Expanded resource %s due to conflict with %s\n", new->name, conflict->name);
748 }
749 write_unlock(&resource_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700750}
751
Toshi Kaniae8e3a92013-04-29 15:08:17 -0700752static int __adjust_resource(struct resource *res, resource_size_t start,
753 resource_size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700754{
755 struct resource *tmp, *parent = res->parent;
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700756 resource_size_t end = start + size - 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757 int result = -EBUSY;
758
Yinghai Lu82ec90e2012-05-17 18:51:11 -0700759 if (!parent)
760 goto skip;
761
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762 if ((start < parent->start) || (end > parent->end))
763 goto out;
764
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765 if (res->sibling && (res->sibling->start <= end))
766 goto out;
767
768 tmp = parent->child;
769 if (tmp != res) {
770 while (tmp->sibling != res)
771 tmp = tmp->sibling;
772 if (start <= tmp->end)
773 goto out;
774 }
775
Yinghai Lu82ec90e2012-05-17 18:51:11 -0700776skip:
777 for (tmp = res->child; tmp; tmp = tmp->sibling)
778 if ((tmp->start < start) || (tmp->end > end))
779 goto out;
780
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781 res->start = start;
782 res->end = end;
783 result = 0;
784
785 out:
Toshi Kaniae8e3a92013-04-29 15:08:17 -0700786 return result;
787}
788
789/**
790 * adjust_resource - modify a resource's start and size
791 * @res: resource to modify
792 * @start: new start value
793 * @size: new size
794 *
795 * Given an existing resource, change its start and size to match the
796 * arguments. Returns 0 on success, -EBUSY if it can't fit.
797 * Existing children of the resource are assumed to be immutable.
798 */
799int adjust_resource(struct resource *res, resource_size_t start,
800 resource_size_t size)
801{
802 int result;
803
804 write_lock(&resource_lock);
805 result = __adjust_resource(res, start, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806 write_unlock(&resource_lock);
807 return result;
808}
Cong Wang24105742012-02-03 21:42:39 +0800809EXPORT_SYMBOL(adjust_resource);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810
Yinghai Lu268364a2008-09-04 21:02:44 +0200811static void __init __reserve_region_with_split(struct resource *root,
812 resource_size_t start, resource_size_t end,
813 const char *name)
814{
815 struct resource *parent = root;
816 struct resource *conflict;
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -0700817 struct resource *res = alloc_resource(GFP_ATOMIC);
T Makphaibulchoke4965f562012-10-04 17:16:55 -0700818 struct resource *next_res = NULL;
Yinghai Lu268364a2008-09-04 21:02:44 +0200819
820 if (!res)
821 return;
822
823 res->name = name;
824 res->start = start;
825 res->end = end;
826 res->flags = IORESOURCE_BUSY;
827
T Makphaibulchoke4965f562012-10-04 17:16:55 -0700828 while (1) {
Yinghai Lu268364a2008-09-04 21:02:44 +0200829
T Makphaibulchoke4965f562012-10-04 17:16:55 -0700830 conflict = __request_resource(parent, res);
831 if (!conflict) {
832 if (!next_res)
833 break;
834 res = next_res;
835 next_res = NULL;
836 continue;
837 }
Yinghai Lu268364a2008-09-04 21:02:44 +0200838
T Makphaibulchoke4965f562012-10-04 17:16:55 -0700839 /* conflict covered whole area */
840 if (conflict->start <= res->start &&
841 conflict->end >= res->end) {
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -0700842 free_resource(res);
T Makphaibulchoke4965f562012-10-04 17:16:55 -0700843 WARN_ON(next_res);
844 break;
845 }
Yinghai Lu268364a2008-09-04 21:02:44 +0200846
T Makphaibulchoke4965f562012-10-04 17:16:55 -0700847 /* failed, split and try again */
848 if (conflict->start > res->start) {
849 end = res->end;
850 res->end = conflict->start - 1;
851 if (conflict->end < end) {
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -0700852 next_res = alloc_resource(GFP_ATOMIC);
T Makphaibulchoke4965f562012-10-04 17:16:55 -0700853 if (!next_res) {
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -0700854 free_resource(res);
T Makphaibulchoke4965f562012-10-04 17:16:55 -0700855 break;
856 }
857 next_res->name = name;
858 next_res->start = conflict->end + 1;
859 next_res->end = end;
860 next_res->flags = IORESOURCE_BUSY;
861 }
862 } else {
863 res->start = conflict->end + 1;
864 }
865 }
866
Yinghai Lu268364a2008-09-04 21:02:44 +0200867}
868
Paul Mundtbea92112008-10-22 19:31:11 +0900869void __init reserve_region_with_split(struct resource *root,
Yinghai Lu268364a2008-09-04 21:02:44 +0200870 resource_size_t start, resource_size_t end,
871 const char *name)
872{
Octavian Purdila65fed8f2012-07-30 14:42:58 -0700873 int abort = 0;
874
Yinghai Lu268364a2008-09-04 21:02:44 +0200875 write_lock(&resource_lock);
Octavian Purdila65fed8f2012-07-30 14:42:58 -0700876 if (root->start > start || root->end < end) {
877 pr_err("requested range [0x%llx-0x%llx] not in root %pr\n",
878 (unsigned long long)start, (unsigned long long)end,
879 root);
880 if (start > root->end || end < root->start)
881 abort = 1;
882 else {
883 if (end > root->end)
884 end = root->end;
885 if (start < root->start)
886 start = root->start;
887 pr_err("fixing request to [0x%llx-0x%llx]\n",
888 (unsigned long long)start,
889 (unsigned long long)end);
890 }
891 dump_stack();
892 }
893 if (!abort)
894 __reserve_region_with_split(root, start, end, name);
Yinghai Lu268364a2008-09-04 21:02:44 +0200895 write_unlock(&resource_lock);
896}
897
Ivan Kokshaysky88452562008-03-30 19:50:14 +0400898/**
899 * resource_alignment - calculate resource's alignment
900 * @res: resource pointer
901 *
902 * Returns alignment on success, 0 (invalid alignment) on failure.
903 */
904resource_size_t resource_alignment(struct resource *res)
905{
906 switch (res->flags & (IORESOURCE_SIZEALIGN | IORESOURCE_STARTALIGN)) {
907 case IORESOURCE_SIZEALIGN:
Magnus Damm1a4e5642008-07-29 22:32:57 -0700908 return resource_size(res);
Ivan Kokshaysky88452562008-03-30 19:50:14 +0400909 case IORESOURCE_STARTALIGN:
910 return res->start;
911 default:
912 return 0;
913 }
914}
915
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916/*
917 * This is compatibility stuff for IO resources.
918 *
919 * Note how this, unlike the above, knows about
920 * the IO flag meanings (busy etc).
921 *
Randy Dunlape1ca66d1b2006-10-03 01:13:51 -0700922 * request_region creates a new busy region.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700923 *
Randy Dunlape1ca66d1b2006-10-03 01:13:51 -0700924 * check_region returns non-zero if the area is already busy.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925 *
Randy Dunlape1ca66d1b2006-10-03 01:13:51 -0700926 * release_region releases a matching busy region.
927 */
928
Alan Cox8b6d0432010-03-29 19:38:00 +0200929static DECLARE_WAIT_QUEUE_HEAD(muxed_resource_wait);
930
Randy Dunlape1ca66d1b2006-10-03 01:13:51 -0700931/**
932 * __request_region - create a new busy resource region
933 * @parent: parent resource descriptor
934 * @start: resource start address
935 * @n: resource region size
936 * @name: reserving caller's ID string
Randy Dunlap6ae301e2009-01-15 13:51:01 -0800937 * @flags: IO resource flags
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938 */
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700939struct resource * __request_region(struct resource *parent,
940 resource_size_t start, resource_size_t n,
Arjan van de Vene8de1482008-10-22 19:55:31 -0700941 const char *name, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700942{
Alan Cox8b6d0432010-03-29 19:38:00 +0200943 DECLARE_WAITQUEUE(wait, current);
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -0700944 struct resource *res = alloc_resource(GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700946 if (!res)
947 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700948
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700949 res->name = name;
950 res->start = start;
951 res->end = start + n - 1;
952 res->flags = IORESOURCE_BUSY;
Arjan van de Vene8de1482008-10-22 19:55:31 -0700953 res->flags |= flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700954
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700955 write_lock(&resource_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700956
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700957 for (;;) {
958 struct resource *conflict;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700959
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700960 conflict = __request_resource(parent, res);
961 if (!conflict)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700962 break;
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700963 if (conflict != parent) {
964 parent = conflict;
965 if (!(conflict->flags & IORESOURCE_BUSY))
966 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700967 }
Alan Cox8b6d0432010-03-29 19:38:00 +0200968 if (conflict->flags & flags & IORESOURCE_MUXED) {
969 add_wait_queue(&muxed_resource_wait, &wait);
970 write_unlock(&resource_lock);
971 set_current_state(TASK_UNINTERRUPTIBLE);
972 schedule();
973 remove_wait_queue(&muxed_resource_wait, &wait);
974 write_lock(&resource_lock);
975 continue;
976 }
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700977 /* Uhhuh, that didn't work out.. */
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -0700978 free_resource(res);
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700979 res = NULL;
980 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700981 }
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700982 write_unlock(&resource_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700983 return res;
984}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985EXPORT_SYMBOL(__request_region);
986
Randy Dunlape1ca66d1b2006-10-03 01:13:51 -0700987/**
988 * __check_region - check if a resource region is busy or free
989 * @parent: parent resource descriptor
990 * @start: resource start address
991 * @n: resource region size
992 *
993 * Returns 0 if the region is free at the moment it is checked,
994 * returns %-EBUSY if the region is busy.
995 *
996 * NOTE:
997 * This function is deprecated because its use is racy.
998 * Even if it returns 0, a subsequent call to request_region()
999 * may fail because another driver etc. just allocated the region.
1000 * Do NOT use it. It will be removed from the kernel.
1001 */
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -07001002int __check_region(struct resource *parent, resource_size_t start,
1003 resource_size_t n)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004{
1005 struct resource * res;
1006
Arjan van de Vene8de1482008-10-22 19:55:31 -07001007 res = __request_region(parent, start, n, "check-region", 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001008 if (!res)
1009 return -EBUSY;
1010
1011 release_resource(res);
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -07001012 free_resource(res);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001013 return 0;
1014}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001015EXPORT_SYMBOL(__check_region);
1016
Randy Dunlape1ca66d1b2006-10-03 01:13:51 -07001017/**
1018 * __release_region - release a previously reserved resource region
1019 * @parent: parent resource descriptor
1020 * @start: resource start address
1021 * @n: resource region size
1022 *
1023 * The described resource region must match a currently busy region.
1024 */
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -07001025void __release_region(struct resource *parent, resource_size_t start,
1026 resource_size_t n)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001027{
1028 struct resource **p;
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -07001029 resource_size_t end;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001030
1031 p = &parent->child;
1032 end = start + n - 1;
1033
1034 write_lock(&resource_lock);
1035
1036 for (;;) {
1037 struct resource *res = *p;
1038
1039 if (!res)
1040 break;
1041 if (res->start <= start && res->end >= end) {
1042 if (!(res->flags & IORESOURCE_BUSY)) {
1043 p = &res->child;
1044 continue;
1045 }
1046 if (res->start != start || res->end != end)
1047 break;
1048 *p = res->sibling;
1049 write_unlock(&resource_lock);
Alan Cox8b6d0432010-03-29 19:38:00 +02001050 if (res->flags & IORESOURCE_MUXED)
1051 wake_up(&muxed_resource_wait);
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -07001052 free_resource(res);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001053 return;
1054 }
1055 p = &res->sibling;
1056 }
1057
1058 write_unlock(&resource_lock);
1059
Greg Kroah-Hartman685143ac2006-06-12 15:18:31 -07001060 printk(KERN_WARNING "Trying to free nonexistent resource "
1061 "<%016llx-%016llx>\n", (unsigned long long)start,
1062 (unsigned long long)end);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001063}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001064EXPORT_SYMBOL(__release_region);
1065
Toshi Kani825f7872013-04-29 15:08:19 -07001066#ifdef CONFIG_MEMORY_HOTREMOVE
1067/**
1068 * release_mem_region_adjustable - release a previously reserved memory region
1069 * @parent: parent resource descriptor
1070 * @start: resource start address
1071 * @size: resource region size
1072 *
1073 * This interface is intended for memory hot-delete. The requested region
1074 * is released from a currently busy memory resource. The requested region
1075 * must either match exactly or fit into a single busy resource entry. In
1076 * the latter case, the remaining resource is adjusted accordingly.
1077 * Existing children of the busy memory resource must be immutable in the
1078 * request.
1079 *
1080 * Note:
1081 * - Additional release conditions, such as overlapping region, can be
1082 * supported after they are confirmed as valid cases.
1083 * - When a busy memory resource gets split into two entries, the code
1084 * assumes that all children remain in the lower address entry for
1085 * simplicity. Enhance this logic when necessary.
1086 */
1087int release_mem_region_adjustable(struct resource *parent,
1088 resource_size_t start, resource_size_t size)
1089{
1090 struct resource **p;
1091 struct resource *res;
1092 struct resource *new_res;
1093 resource_size_t end;
1094 int ret = -EINVAL;
1095
1096 end = start + size - 1;
1097 if ((start < parent->start) || (end > parent->end))
1098 return ret;
1099
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -07001100 /* The alloc_resource() result gets checked later */
1101 new_res = alloc_resource(GFP_KERNEL);
Toshi Kani825f7872013-04-29 15:08:19 -07001102
1103 p = &parent->child;
1104 write_lock(&resource_lock);
1105
1106 while ((res = *p)) {
1107 if (res->start >= end)
1108 break;
1109
1110 /* look for the next resource if it does not fit into */
1111 if (res->start > start || res->end < end) {
1112 p = &res->sibling;
1113 continue;
1114 }
1115
1116 if (!(res->flags & IORESOURCE_MEM))
1117 break;
1118
1119 if (!(res->flags & IORESOURCE_BUSY)) {
1120 p = &res->child;
1121 continue;
1122 }
1123
1124 /* found the target resource; let's adjust accordingly */
1125 if (res->start == start && res->end == end) {
1126 /* free the whole entry */
1127 *p = res->sibling;
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -07001128 free_resource(res);
Toshi Kani825f7872013-04-29 15:08:19 -07001129 ret = 0;
1130 } else if (res->start == start && res->end != end) {
1131 /* adjust the start */
1132 ret = __adjust_resource(res, end + 1,
1133 res->end - end);
1134 } else if (res->start != start && res->end == end) {
1135 /* adjust the end */
1136 ret = __adjust_resource(res, res->start,
1137 start - res->start);
1138 } else {
1139 /* split into two entries */
1140 if (!new_res) {
1141 ret = -ENOMEM;
1142 break;
1143 }
1144 new_res->name = res->name;
1145 new_res->start = end + 1;
1146 new_res->end = res->end;
1147 new_res->flags = res->flags;
1148 new_res->parent = res->parent;
1149 new_res->sibling = res->sibling;
1150 new_res->child = NULL;
1151
1152 ret = __adjust_resource(res, res->start,
1153 start - res->start);
1154 if (ret)
1155 break;
1156 res->sibling = new_res;
1157 new_res = NULL;
1158 }
1159
1160 break;
1161 }
1162
1163 write_unlock(&resource_lock);
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -07001164 free_resource(new_res);
Toshi Kani825f7872013-04-29 15:08:19 -07001165 return ret;
1166}
1167#endif /* CONFIG_MEMORY_HOTREMOVE */
1168
Linus Torvalds1da177e2005-04-16 15:20:36 -07001169/*
Tejun Heo9ac78492007-01-20 16:00:26 +09001170 * Managed region resource
1171 */
1172struct region_devres {
1173 struct resource *parent;
1174 resource_size_t start;
1175 resource_size_t n;
1176};
1177
1178static void devm_region_release(struct device *dev, void *res)
1179{
1180 struct region_devres *this = res;
1181
1182 __release_region(this->parent, this->start, this->n);
1183}
1184
1185static int devm_region_match(struct device *dev, void *res, void *match_data)
1186{
1187 struct region_devres *this = res, *match = match_data;
1188
1189 return this->parent == match->parent &&
1190 this->start == match->start && this->n == match->n;
1191}
1192
1193struct resource * __devm_request_region(struct device *dev,
1194 struct resource *parent, resource_size_t start,
1195 resource_size_t n, const char *name)
1196{
1197 struct region_devres *dr = NULL;
1198 struct resource *res;
1199
1200 dr = devres_alloc(devm_region_release, sizeof(struct region_devres),
1201 GFP_KERNEL);
1202 if (!dr)
1203 return NULL;
1204
1205 dr->parent = parent;
1206 dr->start = start;
1207 dr->n = n;
1208
Arjan van de Vene8de1482008-10-22 19:55:31 -07001209 res = __request_region(parent, start, n, name, 0);
Tejun Heo9ac78492007-01-20 16:00:26 +09001210 if (res)
1211 devres_add(dev, dr);
1212 else
1213 devres_free(dr);
1214
1215 return res;
1216}
1217EXPORT_SYMBOL(__devm_request_region);
1218
1219void __devm_release_region(struct device *dev, struct resource *parent,
1220 resource_size_t start, resource_size_t n)
1221{
1222 struct region_devres match_data = { parent, start, n };
1223
1224 __release_region(parent, start, n);
1225 WARN_ON(devres_destroy(dev, devm_region_release, devm_region_match,
1226 &match_data));
1227}
1228EXPORT_SYMBOL(__devm_release_region);
1229
1230/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001231 * Called from init/main.c to reserve IO ports.
1232 */
1233#define MAXRESERVE 4
1234static int __init reserve_setup(char *str)
1235{
1236 static int reserved;
1237 static struct resource reserve[MAXRESERVE];
1238
1239 for (;;) {
Zhang Rui8bc1ad72009-06-30 11:41:31 -07001240 unsigned int io_start, io_num;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001241 int x = reserved;
1242
1243 if (get_option (&str, &io_start) != 2)
1244 break;
1245 if (get_option (&str, &io_num) == 0)
1246 break;
1247 if (x < MAXRESERVE) {
1248 struct resource *res = reserve + x;
1249 res->name = "reserved";
1250 res->start = io_start;
1251 res->end = io_start + io_num - 1;
1252 res->flags = IORESOURCE_BUSY;
1253 res->child = NULL;
1254 if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, res) == 0)
1255 reserved = x+1;
1256 }
1257 }
1258 return 1;
1259}
1260
1261__setup("reserve=", reserve_setup);
Suresh Siddha379daf62008-09-25 18:43:34 -07001262
1263/*
1264 * Check if the requested addr and size spans more than any slot in the
1265 * iomem resource tree.
1266 */
1267int iomem_map_sanity_check(resource_size_t addr, unsigned long size)
1268{
1269 struct resource *p = &iomem_resource;
1270 int err = 0;
1271 loff_t l;
1272
1273 read_lock(&resource_lock);
1274 for (p = p->child; p ; p = r_next(NULL, p, &l)) {
1275 /*
1276 * We can probably skip the resources without
1277 * IORESOURCE_IO attribute?
1278 */
1279 if (p->start >= addr + size)
1280 continue;
1281 if (p->end < addr)
1282 continue;
Suresh Siddhad68612b2008-10-28 11:45:42 -07001283 if (PFN_DOWN(p->start) <= PFN_DOWN(addr) &&
1284 PFN_DOWN(p->end) >= PFN_DOWN(addr + size - 1))
Suresh Siddha379daf62008-09-25 18:43:34 -07001285 continue;
Arjan van de Ven3ac52662008-12-13 09:15:27 -08001286 /*
1287 * if a resource is "BUSY", it's not a hardware resource
1288 * but a driver mapping of such a resource; we don't want
1289 * to warn for those; some drivers legitimately map only
1290 * partial hardware resources. (example: vesafb)
1291 */
1292 if (p->flags & IORESOURCE_BUSY)
1293 continue;
1294
Suresh Siddha379daf62008-09-25 18:43:34 -07001295 printk(KERN_WARNING "resource map sanity check conflict: "
1296 "0x%llx 0x%llx 0x%llx 0x%llx %s\n",
Ingo Molnar13eb8372008-09-26 10:10:12 +02001297 (unsigned long long)addr,
1298 (unsigned long long)(addr + size - 1),
1299 (unsigned long long)p->start,
1300 (unsigned long long)p->end,
1301 p->name);
Suresh Siddha379daf62008-09-25 18:43:34 -07001302 err = -1;
1303 break;
1304 }
1305 read_unlock(&resource_lock);
1306
1307 return err;
1308}
Arjan van de Vene8de1482008-10-22 19:55:31 -07001309
1310#ifdef CONFIG_STRICT_DEVMEM
1311static int strict_iomem_checks = 1;
1312#else
1313static int strict_iomem_checks;
1314#endif
1315
1316/*
1317 * check if an address is reserved in the iomem resource tree
1318 * returns 1 if reserved, 0 if not reserved.
1319 */
1320int iomem_is_exclusive(u64 addr)
1321{
1322 struct resource *p = &iomem_resource;
1323 int err = 0;
1324 loff_t l;
1325 int size = PAGE_SIZE;
1326
1327 if (!strict_iomem_checks)
1328 return 0;
1329
1330 addr = addr & PAGE_MASK;
1331
1332 read_lock(&resource_lock);
1333 for (p = p->child; p ; p = r_next(NULL, p, &l)) {
1334 /*
1335 * We can probably skip the resources without
1336 * IORESOURCE_IO attribute?
1337 */
1338 if (p->start >= addr + size)
1339 break;
1340 if (p->end < addr)
1341 continue;
1342 if (p->flags & IORESOURCE_BUSY &&
1343 p->flags & IORESOURCE_EXCLUSIVE) {
1344 err = 1;
1345 break;
1346 }
1347 }
1348 read_unlock(&resource_lock);
1349
1350 return err;
1351}
1352
1353static int __init strict_iomem(char *str)
1354{
1355 if (strstr(str, "relaxed"))
1356 strict_iomem_checks = 0;
1357 if (strstr(str, "strict"))
1358 strict_iomem_checks = 1;
1359 return 1;
1360}
1361
1362__setup("iomem=", strict_iomem);