blob: 798e2fae2a069645c13853f4b658dada92af8f66 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/kernel/resource.c
3 *
4 * Copyright (C) 1999 Linus Torvalds
5 * Copyright (C) 1999 Martin Mares <mj@ucw.cz>
6 *
7 * Arbitrary resource management.
8 */
9
Linus Torvalds1da177e2005-04-16 15:20:36 -070010#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070011#include <linux/errno.h>
12#include <linux/ioport.h>
13#include <linux/init.h>
14#include <linux/slab.h>
15#include <linux/spinlock.h>
16#include <linux/fs.h>
17#include <linux/proc_fs.h>
Alan Cox8b6d0432010-03-29 19:38:00 +020018#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070019#include <linux/seq_file.h>
Tejun Heo9ac78492007-01-20 16:00:26 +090020#include <linux/device.h>
Suresh Siddhad68612b2008-10-28 11:45:42 -070021#include <linux/pfn.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <asm/io.h>
23
24
25struct resource ioport_resource = {
26 .name = "PCI IO",
Greg Kroah-Hartman6550e072006-06-12 17:11:31 -070027 .start = 0,
Linus Torvalds1da177e2005-04-16 15:20:36 -070028 .end = IO_SPACE_LIMIT,
29 .flags = IORESOURCE_IO,
30};
Linus Torvalds1da177e2005-04-16 15:20:36 -070031EXPORT_SYMBOL(ioport_resource);
32
33struct resource iomem_resource = {
34 .name = "PCI mem",
Greg Kroah-Hartman6550e072006-06-12 17:11:31 -070035 .start = 0,
36 .end = -1,
Linus Torvalds1da177e2005-04-16 15:20:36 -070037 .flags = IORESOURCE_MEM,
38};
Linus Torvalds1da177e2005-04-16 15:20:36 -070039EXPORT_SYMBOL(iomem_resource);
40
41static DEFINE_RWLOCK(resource_lock);
42
Linus Torvalds1da177e2005-04-16 15:20:36 -070043static void *r_next(struct seq_file *m, void *v, loff_t *pos)
44{
45 struct resource *p = v;
46 (*pos)++;
47 if (p->child)
48 return p->child;
49 while (!p->sibling && p->parent)
50 p = p->parent;
51 return p->sibling;
52}
53
Ingo Molnar13eb8372008-09-26 10:10:12 +020054#ifdef CONFIG_PROC_FS
55
56enum { MAX_IORES_LEVEL = 5 };
57
Linus Torvalds1da177e2005-04-16 15:20:36 -070058static void *r_start(struct seq_file *m, loff_t *pos)
59 __acquires(resource_lock)
60{
61 struct resource *p = m->private;
62 loff_t l = 0;
63 read_lock(&resource_lock);
64 for (p = p->child; p && l < *pos; p = r_next(m, p, &l))
65 ;
66 return p;
67}
68
69static void r_stop(struct seq_file *m, void *v)
70 __releases(resource_lock)
71{
72 read_unlock(&resource_lock);
73}
74
75static int r_show(struct seq_file *m, void *v)
76{
77 struct resource *root = m->private;
78 struct resource *r = v, *p;
79 int width = root->end < 0x10000 ? 4 : 8;
80 int depth;
81
82 for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent)
83 if (p->parent == root)
84 break;
Greg Kroah-Hartman685143ac2006-06-12 15:18:31 -070085 seq_printf(m, "%*s%0*llx-%0*llx : %s\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -070086 depth * 2, "",
Greg Kroah-Hartman685143ac2006-06-12 15:18:31 -070087 width, (unsigned long long) r->start,
88 width, (unsigned long long) r->end,
Linus Torvalds1da177e2005-04-16 15:20:36 -070089 r->name ? r->name : "<BAD>");
90 return 0;
91}
92
Helge Deller15ad7cd2006-12-06 20:40:36 -080093static const struct seq_operations resource_op = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070094 .start = r_start,
95 .next = r_next,
96 .stop = r_stop,
97 .show = r_show,
98};
99
100static int ioports_open(struct inode *inode, struct file *file)
101{
102 int res = seq_open(file, &resource_op);
103 if (!res) {
104 struct seq_file *m = file->private_data;
105 m->private = &ioport_resource;
106 }
107 return res;
108}
109
110static int iomem_open(struct inode *inode, struct file *file)
111{
112 int res = seq_open(file, &resource_op);
113 if (!res) {
114 struct seq_file *m = file->private_data;
115 m->private = &iomem_resource;
116 }
117 return res;
118}
119
Helge Deller15ad7cd2006-12-06 20:40:36 -0800120static const struct file_operations proc_ioports_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121 .open = ioports_open,
122 .read = seq_read,
123 .llseek = seq_lseek,
124 .release = seq_release,
125};
126
Helge Deller15ad7cd2006-12-06 20:40:36 -0800127static const struct file_operations proc_iomem_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128 .open = iomem_open,
129 .read = seq_read,
130 .llseek = seq_lseek,
131 .release = seq_release,
132};
133
134static int __init ioresources_init(void)
135{
Denis V. Lunevc33fff02008-04-29 01:02:31 -0700136 proc_create("ioports", 0, NULL, &proc_ioports_operations);
137 proc_create("iomem", 0, NULL, &proc_iomem_operations);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138 return 0;
139}
140__initcall(ioresources_init);
141
142#endif /* CONFIG_PROC_FS */
143
144/* Return the conflict entry if you can't request it */
145static struct resource * __request_resource(struct resource *root, struct resource *new)
146{
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700147 resource_size_t start = new->start;
148 resource_size_t end = new->end;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149 struct resource *tmp, **p;
150
151 if (end < start)
152 return root;
153 if (start < root->start)
154 return root;
155 if (end > root->end)
156 return root;
157 p = &root->child;
158 for (;;) {
159 tmp = *p;
160 if (!tmp || tmp->start > end) {
161 new->sibling = tmp;
162 *p = new;
163 new->parent = root;
164 return NULL;
165 }
166 p = &tmp->sibling;
167 if (tmp->end < start)
168 continue;
169 return tmp;
170 }
171}
172
173static int __release_resource(struct resource *old)
174{
175 struct resource *tmp, **p;
176
177 p = &old->parent->child;
178 for (;;) {
179 tmp = *p;
180 if (!tmp)
181 break;
182 if (tmp == old) {
183 *p = tmp->sibling;
184 old->parent = NULL;
185 return 0;
186 }
187 p = &tmp->sibling;
188 }
189 return -EINVAL;
190}
191
Yinghai Lu5eeec0e2009-12-22 15:02:22 -0800192static void __release_child_resources(struct resource *r)
193{
194 struct resource *tmp, *p;
195 resource_size_t size;
196
197 p = r->child;
198 r->child = NULL;
199 while (p) {
200 tmp = p;
201 p = p->sibling;
202
203 tmp->parent = NULL;
204 tmp->sibling = NULL;
205 __release_child_resources(tmp);
206
207 printk(KERN_DEBUG "release child resource %pR\n", tmp);
208 /* need to restore size, and keep flags */
209 size = resource_size(tmp);
210 tmp->start = 0;
211 tmp->end = size - 1;
212 }
213}
214
215void release_child_resources(struct resource *r)
216{
217 write_lock(&resource_lock);
218 __release_child_resources(r);
219 write_unlock(&resource_lock);
220}
221
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700222/**
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700223 * request_resource_conflict - request and reserve an I/O or memory resource
224 * @root: root resource descriptor
225 * @new: resource descriptor desired by caller
226 *
227 * Returns 0 for success, conflict resource on error.
228 */
229struct resource *request_resource_conflict(struct resource *root, struct resource *new)
230{
231 struct resource *conflict;
232
233 write_lock(&resource_lock);
234 conflict = __request_resource(root, new);
235 write_unlock(&resource_lock);
236 return conflict;
237}
238
239/**
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700240 * request_resource - request and reserve an I/O or memory resource
241 * @root: root resource descriptor
242 * @new: resource descriptor desired by caller
243 *
244 * Returns 0 for success, negative error code on error.
245 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246int request_resource(struct resource *root, struct resource *new)
247{
248 struct resource *conflict;
249
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700250 conflict = request_resource_conflict(root, new);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251 return conflict ? -EBUSY : 0;
252}
253
254EXPORT_SYMBOL(request_resource);
255
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700256/**
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700257 * release_resource - release a previously reserved resource
258 * @old: resource pointer
259 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260int release_resource(struct resource *old)
261{
262 int retval;
263
264 write_lock(&resource_lock);
265 retval = __release_resource(old);
266 write_unlock(&resource_lock);
267 return retval;
268}
269
270EXPORT_SYMBOL(release_resource);
271
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700272#if !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700273/*
274 * Finds the lowest memory reosurce exists within [res->start.res->end)
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700275 * the caller must specify res->start, res->end, res->flags and "name".
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700276 * If found, returns 0, res is overwritten, if not found, returns -1.
277 */
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700278static int find_next_system_ram(struct resource *res, char *name)
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700279{
280 resource_size_t start, end;
281 struct resource *p;
282
283 BUG_ON(!res);
284
285 start = res->start;
286 end = res->end;
KAMEZAWA Hiroyuki58c1b5b2006-08-05 12:15:01 -0700287 BUG_ON(start >= end);
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700288
289 read_lock(&resource_lock);
290 for (p = iomem_resource.child; p ; p = p->sibling) {
291 /* system ram is just marked as IORESOURCE_MEM */
292 if (p->flags != res->flags)
293 continue;
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700294 if (name && strcmp(p->name, name))
295 continue;
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700296 if (p->start > end) {
297 p = NULL;
298 break;
299 }
KAMEZAWA Hiroyuki58c1b5b2006-08-05 12:15:01 -0700300 if ((p->end >= start) && (p->start < end))
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700301 break;
302 }
303 read_unlock(&resource_lock);
304 if (!p)
305 return -1;
306 /* copy data */
KAMEZAWA Hiroyuki0f04ab52006-08-05 12:14:59 -0700307 if (res->start < p->start)
308 res->start = p->start;
309 if (res->end > p->end)
310 res->end = p->end;
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700311 return 0;
312}
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700313
314/*
315 * This function calls callback against all memory range of "System RAM"
316 * which are marked as IORESOURCE_MEM and IORESOUCE_BUSY.
317 * Now, this function is only for "System RAM".
318 */
319int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
320 void *arg, int (*func)(unsigned long, unsigned long, void *))
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700321{
322 struct resource res;
Wu Fengguang37b99dd2010-03-01 21:55:51 +0800323 unsigned long pfn, end_pfn;
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700324 u64 orig_end;
325 int ret = -1;
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700326
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700327 res.start = (u64) start_pfn << PAGE_SHIFT;
328 res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1;
Yasunori Goto887c3cb2007-11-14 16:59:20 -0800329 res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700330 orig_end = res.end;
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700331 while ((res.start < res.end) &&
332 (find_next_system_ram(&res, "System RAM") >= 0)) {
Wu Fengguang37b99dd2010-03-01 21:55:51 +0800333 pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT;
334 end_pfn = (res.end + 1) >> PAGE_SHIFT;
335 if (end_pfn > pfn)
H. Peter Anvinf4149662010-03-02 11:21:09 -0800336 ret = (*func)(pfn, end_pfn - pfn, arg);
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700337 if (ret)
338 break;
339 res.start = res.end + 1;
340 res.end = orig_end;
341 }
342 return ret;
343}
344
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700345#endif
346
Wu Fengguang61ef2482010-01-22 16:16:19 +0800347static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg)
348{
349 return 1;
350}
351/*
352 * This generic page_is_ram() returns true if specified address is
353 * registered as "System RAM" in iomem_resource list.
354 */
Andrew Mortone5273002010-01-26 16:31:19 -0800355int __weak page_is_ram(unsigned long pfn)
Wu Fengguang61ef2482010-01-22 16:16:19 +0800356{
357 return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1;
358}
359
Bjorn Helgaasfcb11912010-12-16 10:38:46 -0700360void __weak arch_remove_reservations(struct resource *avail)
361{
362}
363
Bjorn Helgaasa9cea012010-10-26 15:41:13 -0600364static resource_size_t simple_align_resource(void *data,
365 const struct resource *avail,
366 resource_size_t size,
367 resource_size_t align)
368{
369 return avail->start;
370}
371
Bjorn Helgaas5d6b1fa2010-10-26 15:41:18 -0600372static void resource_clip(struct resource *res, resource_size_t min,
373 resource_size_t max)
374{
375 if (res->start < min)
376 res->start = min;
377 if (res->end > max)
378 res->end = max;
379}
380
Bjorn Helgaas6909ba12010-10-26 15:41:23 -0600381static bool resource_contains(struct resource *res1, struct resource *res2)
382{
383 return res1->start <= res2->start && res1->end >= res2->end;
384}
385
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386/*
387 * Find empty slot in the resource tree given range and alignment.
388 */
389static int find_resource(struct resource *root, struct resource *new,
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700390 resource_size_t size, resource_size_t min,
391 resource_size_t max, resource_size_t align,
Dominik Brodowskib26b2d42010-01-01 17:40:49 +0100392 resource_size_t (*alignf)(void *,
Dominik Brodowski3b7a17f2010-01-01 17:40:50 +0100393 const struct resource *,
Dominik Brodowskib26b2d42010-01-01 17:40:49 +0100394 resource_size_t,
395 resource_size_t),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700396 void *alignf_data)
397{
398 struct resource *this = root->child;
Bjorn Helgaasa1862e32010-10-26 15:41:28 -0600399 struct resource tmp = *new, avail, alloc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400
Bjorn Helgaasfcb11912010-12-16 10:38:46 -0700401 tmp.flags = new->flags;
Dominik Brodowski0e2c8b82009-12-20 10:50:02 +0100402 tmp.start = root->start;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 /*
Bjorn Helgaasc0f5ac52010-12-16 10:38:41 -0700404 * Skip past an allocated resource that starts at 0, since the assignment
405 * of this->start - 1 to tmp->end below would cause an underflow.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700406 */
407 if (this && this->start == 0) {
Dominik Brodowski0e2c8b82009-12-20 10:50:02 +0100408 tmp.start = this->end + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 this = this->sibling;
410 }
Bjorn Helgaasc0f5ac52010-12-16 10:38:41 -0700411 for(;;) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412 if (this)
Dominik Brodowski0e2c8b82009-12-20 10:50:02 +0100413 tmp.end = this->start - 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414 else
Dominik Brodowski0e2c8b82009-12-20 10:50:02 +0100415 tmp.end = root->end;
Bjorn Helgaas5d6b1fa2010-10-26 15:41:18 -0600416
417 resource_clip(&tmp, min, max);
Bjorn Helgaasfcb11912010-12-16 10:38:46 -0700418 arch_remove_reservations(&tmp);
Bjorn Helgaasa9cea012010-10-26 15:41:13 -0600419
Bjorn Helgaasa1862e32010-10-26 15:41:28 -0600420 /* Check for overflow after ALIGN() */
421 avail = *new;
422 avail.start = ALIGN(tmp.start, align);
423 avail.end = tmp.end;
424 if (avail.start >= tmp.start) {
425 alloc.start = alignf(alignf_data, &avail, size, align);
426 alloc.end = alloc.start + size - 1;
427 if (resource_contains(&avail, &alloc)) {
428 new->start = alloc.start;
429 new->end = alloc.end;
430 return 0;
431 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700432 }
433 if (!this)
434 break;
Dominik Brodowski0e2c8b82009-12-20 10:50:02 +0100435 tmp.start = this->end + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436 this = this->sibling;
437 }
438 return -EBUSY;
439}
440
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700441/**
442 * allocate_resource - allocate empty slot in the resource tree given range & alignment
443 * @root: root resource descriptor
444 * @new: resource descriptor desired by caller
445 * @size: requested resource region size
446 * @min: minimum size to allocate
447 * @max: maximum size to allocate
448 * @align: alignment requested, in bytes
449 * @alignf: alignment function, optional, called if not NULL
450 * @alignf_data: arbitrary data to pass to the @alignf function
Linus Torvalds1da177e2005-04-16 15:20:36 -0700451 */
452int allocate_resource(struct resource *root, struct resource *new,
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700453 resource_size_t size, resource_size_t min,
454 resource_size_t max, resource_size_t align,
Dominik Brodowskib26b2d42010-01-01 17:40:49 +0100455 resource_size_t (*alignf)(void *,
Dominik Brodowski3b7a17f2010-01-01 17:40:50 +0100456 const struct resource *,
Dominik Brodowskib26b2d42010-01-01 17:40:49 +0100457 resource_size_t,
458 resource_size_t),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459 void *alignf_data)
460{
461 int err;
462
Bjorn Helgaasa9cea012010-10-26 15:41:13 -0600463 if (!alignf)
464 alignf = simple_align_resource;
465
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 write_lock(&resource_lock);
Bjorn Helgaasc0f5ac52010-12-16 10:38:41 -0700467 err = find_resource(root, new, size, min, max, align, alignf, alignf_data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468 if (err >= 0 && __request_resource(root, new))
469 err = -EBUSY;
470 write_unlock(&resource_lock);
471 return err;
472}
473
474EXPORT_SYMBOL(allocate_resource);
475
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700476/*
477 * Insert a resource into the resource tree. If successful, return NULL,
478 * otherwise return the conflicting resource (compare to __request_resource())
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479 */
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700480static struct resource * __insert_resource(struct resource *parent, struct resource *new)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700482 struct resource *first, *next;
483
Matthew Wilcoxd33b6fb2006-06-30 02:31:24 -0700484 for (;; parent = first) {
Matthew Wilcoxd33b6fb2006-06-30 02:31:24 -0700485 first = __request_resource(parent, new);
486 if (!first)
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700487 return first;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700488
Matthew Wilcoxd33b6fb2006-06-30 02:31:24 -0700489 if (first == parent)
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700490 return first;
Huang Shijie5de1cb22010-10-27 15:34:52 -0700491 if (WARN_ON(first == new)) /* duplicated insertion */
492 return first;
Matthew Wilcoxd33b6fb2006-06-30 02:31:24 -0700493
494 if ((first->start > new->start) || (first->end < new->end))
495 break;
496 if ((first->start == new->start) && (first->end == new->end))
497 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498 }
499
500 for (next = first; ; next = next->sibling) {
501 /* Partial overlap? Bad, and unfixable */
502 if (next->start < new->start || next->end > new->end)
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700503 return next;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504 if (!next->sibling)
505 break;
506 if (next->sibling->start > new->end)
507 break;
508 }
509
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510 new->parent = parent;
511 new->sibling = next->sibling;
512 new->child = first;
513
514 next->sibling = NULL;
515 for (next = first; next; next = next->sibling)
516 next->parent = new;
517
518 if (parent->child == first) {
519 parent->child = new;
520 } else {
521 next = parent->child;
522 while (next->sibling != first)
523 next = next->sibling;
524 next->sibling = new;
525 }
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700526 return NULL;
527}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700529/**
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700530 * insert_resource_conflict - Inserts resource in the resource tree
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700531 * @parent: parent of the new resource
532 * @new: new resource to insert
533 *
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700534 * Returns 0 on success, conflict resource if the resource can't be inserted.
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700535 *
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700536 * This function is equivalent to request_resource_conflict when no conflict
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700537 * happens. If a conflict happens, and the conflicting resources
538 * entirely fit within the range of the new resource, then the new
539 * resource is inserted and the conflicting resources become children of
540 * the new resource.
541 */
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700542struct resource *insert_resource_conflict(struct resource *parent, struct resource *new)
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700543{
544 struct resource *conflict;
545
546 write_lock(&resource_lock);
547 conflict = __insert_resource(parent, new);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700548 write_unlock(&resource_lock);
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700549 return conflict;
550}
551
552/**
553 * insert_resource - Inserts a resource in the resource tree
554 * @parent: parent of the new resource
555 * @new: new resource to insert
556 *
557 * Returns 0 on success, -EBUSY if the resource can't be inserted.
558 */
559int insert_resource(struct resource *parent, struct resource *new)
560{
561 struct resource *conflict;
562
563 conflict = insert_resource_conflict(parent, new);
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700564 return conflict ? -EBUSY : 0;
565}
566
567/**
568 * insert_resource_expand_to_fit - Insert a resource into the resource tree
Randy Dunlap6781f4a2008-08-31 20:31:55 -0700569 * @root: root resource descriptor
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700570 * @new: new resource to insert
571 *
572 * Insert a resource into the resource tree, possibly expanding it in order
573 * to make it encompass any conflicting resources.
574 */
575void insert_resource_expand_to_fit(struct resource *root, struct resource *new)
576{
577 if (new->parent)
578 return;
579
580 write_lock(&resource_lock);
581 for (;;) {
582 struct resource *conflict;
583
584 conflict = __insert_resource(root, new);
585 if (!conflict)
586 break;
587 if (conflict == root)
588 break;
589
590 /* Ok, expand resource to cover the conflict, then try again .. */
591 if (conflict->start < new->start)
592 new->start = conflict->start;
593 if (conflict->end > new->end)
594 new->end = conflict->end;
595
596 printk("Expanded resource %s due to conflict with %s\n", new->name, conflict->name);
597 }
598 write_unlock(&resource_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599}
600
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700601/**
602 * adjust_resource - modify a resource's start and size
603 * @res: resource to modify
604 * @start: new start value
605 * @size: new size
606 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607 * Given an existing resource, change its start and size to match the
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700608 * arguments. Returns 0 on success, -EBUSY if it can't fit.
609 * Existing children of the resource are assumed to be immutable.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610 */
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700611int adjust_resource(struct resource *res, resource_size_t start, resource_size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612{
613 struct resource *tmp, *parent = res->parent;
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700614 resource_size_t end = start + size - 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615 int result = -EBUSY;
616
617 write_lock(&resource_lock);
618
619 if ((start < parent->start) || (end > parent->end))
620 goto out;
621
622 for (tmp = res->child; tmp; tmp = tmp->sibling) {
623 if ((tmp->start < start) || (tmp->end > end))
624 goto out;
625 }
626
627 if (res->sibling && (res->sibling->start <= end))
628 goto out;
629
630 tmp = parent->child;
631 if (tmp != res) {
632 while (tmp->sibling != res)
633 tmp = tmp->sibling;
634 if (start <= tmp->end)
635 goto out;
636 }
637
638 res->start = start;
639 res->end = end;
640 result = 0;
641
642 out:
643 write_unlock(&resource_lock);
644 return result;
645}
646
Yinghai Lu268364a2008-09-04 21:02:44 +0200647static void __init __reserve_region_with_split(struct resource *root,
648 resource_size_t start, resource_size_t end,
649 const char *name)
650{
651 struct resource *parent = root;
652 struct resource *conflict;
Linus Torvalds42c02022008-11-01 09:53:58 -0700653 struct resource *res = kzalloc(sizeof(*res), GFP_ATOMIC);
Yinghai Lu268364a2008-09-04 21:02:44 +0200654
655 if (!res)
656 return;
657
658 res->name = name;
659 res->start = start;
660 res->end = end;
661 res->flags = IORESOURCE_BUSY;
662
Linus Torvaldsff542502009-04-18 21:44:24 -0700663 conflict = __request_resource(parent, res);
664 if (!conflict)
665 return;
Yinghai Lu268364a2008-09-04 21:02:44 +0200666
Linus Torvaldsff542502009-04-18 21:44:24 -0700667 /* failed, split and try again */
668 kfree(res);
Yinghai Lu268364a2008-09-04 21:02:44 +0200669
Linus Torvaldsff542502009-04-18 21:44:24 -0700670 /* conflict covered whole area */
671 if (conflict->start <= start && conflict->end >= end)
672 return;
Yinghai Lu268364a2008-09-04 21:02:44 +0200673
Linus Torvaldsff542502009-04-18 21:44:24 -0700674 if (conflict->start > start)
675 __reserve_region_with_split(root, start, conflict->start-1, name);
676 if (conflict->end < end)
677 __reserve_region_with_split(root, conflict->end+1, end, name);
Yinghai Lu268364a2008-09-04 21:02:44 +0200678}
679
Paul Mundtbea92112008-10-22 19:31:11 +0900680void __init reserve_region_with_split(struct resource *root,
Yinghai Lu268364a2008-09-04 21:02:44 +0200681 resource_size_t start, resource_size_t end,
682 const char *name)
683{
684 write_lock(&resource_lock);
685 __reserve_region_with_split(root, start, end, name);
686 write_unlock(&resource_lock);
687}
688
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689EXPORT_SYMBOL(adjust_resource);
690
Ivan Kokshaysky88452562008-03-30 19:50:14 +0400691/**
692 * resource_alignment - calculate resource's alignment
693 * @res: resource pointer
694 *
695 * Returns alignment on success, 0 (invalid alignment) on failure.
696 */
697resource_size_t resource_alignment(struct resource *res)
698{
699 switch (res->flags & (IORESOURCE_SIZEALIGN | IORESOURCE_STARTALIGN)) {
700 case IORESOURCE_SIZEALIGN:
Magnus Damm1a4e5642008-07-29 22:32:57 -0700701 return resource_size(res);
Ivan Kokshaysky88452562008-03-30 19:50:14 +0400702 case IORESOURCE_STARTALIGN:
703 return res->start;
704 default:
705 return 0;
706 }
707}
708
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709/*
710 * This is compatibility stuff for IO resources.
711 *
712 * Note how this, unlike the above, knows about
713 * the IO flag meanings (busy etc).
714 *
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700715 * request_region creates a new busy region.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716 *
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700717 * check_region returns non-zero if the area is already busy.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700718 *
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700719 * release_region releases a matching busy region.
720 */
721
Alan Cox8b6d0432010-03-29 19:38:00 +0200722static DECLARE_WAIT_QUEUE_HEAD(muxed_resource_wait);
723
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700724/**
725 * __request_region - create a new busy resource region
726 * @parent: parent resource descriptor
727 * @start: resource start address
728 * @n: resource region size
729 * @name: reserving caller's ID string
Randy Dunlap6ae301e2009-01-15 13:51:01 -0800730 * @flags: IO resource flags
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731 */
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700732struct resource * __request_region(struct resource *parent,
733 resource_size_t start, resource_size_t n,
Arjan van de Vene8de1482008-10-22 19:55:31 -0700734 const char *name, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700735{
Alan Cox8b6d0432010-03-29 19:38:00 +0200736 DECLARE_WAITQUEUE(wait, current);
Pekka J Enbergdd392712005-09-06 15:18:31 -0700737 struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700739 if (!res)
740 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700742 res->name = name;
743 res->start = start;
744 res->end = start + n - 1;
745 res->flags = IORESOURCE_BUSY;
Arjan van de Vene8de1482008-10-22 19:55:31 -0700746 res->flags |= flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700748 write_lock(&resource_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700750 for (;;) {
751 struct resource *conflict;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700753 conflict = __request_resource(parent, res);
754 if (!conflict)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755 break;
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700756 if (conflict != parent) {
757 parent = conflict;
758 if (!(conflict->flags & IORESOURCE_BUSY))
759 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700760 }
Alan Cox8b6d0432010-03-29 19:38:00 +0200761 if (conflict->flags & flags & IORESOURCE_MUXED) {
762 add_wait_queue(&muxed_resource_wait, &wait);
763 write_unlock(&resource_lock);
764 set_current_state(TASK_UNINTERRUPTIBLE);
765 schedule();
766 remove_wait_queue(&muxed_resource_wait, &wait);
767 write_lock(&resource_lock);
768 continue;
769 }
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700770 /* Uhhuh, that didn't work out.. */
771 kfree(res);
772 res = NULL;
773 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700774 }
Bjorn Helgaasc26ec882008-10-15 22:05:14 -0700775 write_unlock(&resource_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776 return res;
777}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778EXPORT_SYMBOL(__request_region);
779
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700780/**
781 * __check_region - check if a resource region is busy or free
782 * @parent: parent resource descriptor
783 * @start: resource start address
784 * @n: resource region size
785 *
786 * Returns 0 if the region is free at the moment it is checked,
787 * returns %-EBUSY if the region is busy.
788 *
789 * NOTE:
790 * This function is deprecated because its use is racy.
791 * Even if it returns 0, a subsequent call to request_region()
792 * may fail because another driver etc. just allocated the region.
793 * Do NOT use it. It will be removed from the kernel.
794 */
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700795int __check_region(struct resource *parent, resource_size_t start,
796 resource_size_t n)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797{
798 struct resource * res;
799
Arjan van de Vene8de1482008-10-22 19:55:31 -0700800 res = __request_region(parent, start, n, "check-region", 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700801 if (!res)
802 return -EBUSY;
803
804 release_resource(res);
805 kfree(res);
806 return 0;
807}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808EXPORT_SYMBOL(__check_region);
809
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700810/**
811 * __release_region - release a previously reserved resource region
812 * @parent: parent resource descriptor
813 * @start: resource start address
814 * @n: resource region size
815 *
816 * The described resource region must match a currently busy region.
817 */
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700818void __release_region(struct resource *parent, resource_size_t start,
819 resource_size_t n)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820{
821 struct resource **p;
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700822 resource_size_t end;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700823
824 p = &parent->child;
825 end = start + n - 1;
826
827 write_lock(&resource_lock);
828
829 for (;;) {
830 struct resource *res = *p;
831
832 if (!res)
833 break;
834 if (res->start <= start && res->end >= end) {
835 if (!(res->flags & IORESOURCE_BUSY)) {
836 p = &res->child;
837 continue;
838 }
839 if (res->start != start || res->end != end)
840 break;
841 *p = res->sibling;
842 write_unlock(&resource_lock);
Alan Cox8b6d0432010-03-29 19:38:00 +0200843 if (res->flags & IORESOURCE_MUXED)
844 wake_up(&muxed_resource_wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700845 kfree(res);
846 return;
847 }
848 p = &res->sibling;
849 }
850
851 write_unlock(&resource_lock);
852
Greg Kroah-Hartman685143ac2006-06-12 15:18:31 -0700853 printk(KERN_WARNING "Trying to free nonexistent resource "
854 "<%016llx-%016llx>\n", (unsigned long long)start,
855 (unsigned long long)end);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700856}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857EXPORT_SYMBOL(__release_region);
858
859/*
Tejun Heo9ac78492007-01-20 16:00:26 +0900860 * Managed region resource
861 */
862struct region_devres {
863 struct resource *parent;
864 resource_size_t start;
865 resource_size_t n;
866};
867
868static void devm_region_release(struct device *dev, void *res)
869{
870 struct region_devres *this = res;
871
872 __release_region(this->parent, this->start, this->n);
873}
874
875static int devm_region_match(struct device *dev, void *res, void *match_data)
876{
877 struct region_devres *this = res, *match = match_data;
878
879 return this->parent == match->parent &&
880 this->start == match->start && this->n == match->n;
881}
882
883struct resource * __devm_request_region(struct device *dev,
884 struct resource *parent, resource_size_t start,
885 resource_size_t n, const char *name)
886{
887 struct region_devres *dr = NULL;
888 struct resource *res;
889
890 dr = devres_alloc(devm_region_release, sizeof(struct region_devres),
891 GFP_KERNEL);
892 if (!dr)
893 return NULL;
894
895 dr->parent = parent;
896 dr->start = start;
897 dr->n = n;
898
Arjan van de Vene8de1482008-10-22 19:55:31 -0700899 res = __request_region(parent, start, n, name, 0);
Tejun Heo9ac78492007-01-20 16:00:26 +0900900 if (res)
901 devres_add(dev, dr);
902 else
903 devres_free(dr);
904
905 return res;
906}
907EXPORT_SYMBOL(__devm_request_region);
908
909void __devm_release_region(struct device *dev, struct resource *parent,
910 resource_size_t start, resource_size_t n)
911{
912 struct region_devres match_data = { parent, start, n };
913
914 __release_region(parent, start, n);
915 WARN_ON(devres_destroy(dev, devm_region_release, devm_region_match,
916 &match_data));
917}
918EXPORT_SYMBOL(__devm_release_region);
919
920/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700921 * Called from init/main.c to reserve IO ports.
922 */
923#define MAXRESERVE 4
924static int __init reserve_setup(char *str)
925{
926 static int reserved;
927 static struct resource reserve[MAXRESERVE];
928
929 for (;;) {
Zhang Rui8bc1ad72009-06-30 11:41:31 -0700930 unsigned int io_start, io_num;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700931 int x = reserved;
932
933 if (get_option (&str, &io_start) != 2)
934 break;
935 if (get_option (&str, &io_num) == 0)
936 break;
937 if (x < MAXRESERVE) {
938 struct resource *res = reserve + x;
939 res->name = "reserved";
940 res->start = io_start;
941 res->end = io_start + io_num - 1;
942 res->flags = IORESOURCE_BUSY;
943 res->child = NULL;
944 if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, res) == 0)
945 reserved = x+1;
946 }
947 }
948 return 1;
949}
950
951__setup("reserve=", reserve_setup);
Suresh Siddha379daf62008-09-25 18:43:34 -0700952
953/*
954 * Check if the requested addr and size spans more than any slot in the
955 * iomem resource tree.
956 */
957int iomem_map_sanity_check(resource_size_t addr, unsigned long size)
958{
959 struct resource *p = &iomem_resource;
960 int err = 0;
961 loff_t l;
962
963 read_lock(&resource_lock);
964 for (p = p->child; p ; p = r_next(NULL, p, &l)) {
965 /*
966 * We can probably skip the resources without
967 * IORESOURCE_IO attribute?
968 */
969 if (p->start >= addr + size)
970 continue;
971 if (p->end < addr)
972 continue;
Suresh Siddhad68612b2008-10-28 11:45:42 -0700973 if (PFN_DOWN(p->start) <= PFN_DOWN(addr) &&
974 PFN_DOWN(p->end) >= PFN_DOWN(addr + size - 1))
Suresh Siddha379daf62008-09-25 18:43:34 -0700975 continue;
Arjan van de Ven3ac52662008-12-13 09:15:27 -0800976 /*
977 * if a resource is "BUSY", it's not a hardware resource
978 * but a driver mapping of such a resource; we don't want
979 * to warn for those; some drivers legitimately map only
980 * partial hardware resources. (example: vesafb)
981 */
982 if (p->flags & IORESOURCE_BUSY)
983 continue;
984
Suresh Siddha379daf62008-09-25 18:43:34 -0700985 printk(KERN_WARNING "resource map sanity check conflict: "
986 "0x%llx 0x%llx 0x%llx 0x%llx %s\n",
Ingo Molnar13eb8372008-09-26 10:10:12 +0200987 (unsigned long long)addr,
988 (unsigned long long)(addr + size - 1),
989 (unsigned long long)p->start,
990 (unsigned long long)p->end,
991 p->name);
Suresh Siddha379daf62008-09-25 18:43:34 -0700992 err = -1;
993 break;
994 }
995 read_unlock(&resource_lock);
996
997 return err;
998}
Arjan van de Vene8de1482008-10-22 19:55:31 -0700999
1000#ifdef CONFIG_STRICT_DEVMEM
1001static int strict_iomem_checks = 1;
1002#else
1003static int strict_iomem_checks;
1004#endif
1005
1006/*
1007 * check if an address is reserved in the iomem resource tree
1008 * returns 1 if reserved, 0 if not reserved.
1009 */
1010int iomem_is_exclusive(u64 addr)
1011{
1012 struct resource *p = &iomem_resource;
1013 int err = 0;
1014 loff_t l;
1015 int size = PAGE_SIZE;
1016
1017 if (!strict_iomem_checks)
1018 return 0;
1019
1020 addr = addr & PAGE_MASK;
1021
1022 read_lock(&resource_lock);
1023 for (p = p->child; p ; p = r_next(NULL, p, &l)) {
1024 /*
1025 * We can probably skip the resources without
1026 * IORESOURCE_IO attribute?
1027 */
1028 if (p->start >= addr + size)
1029 break;
1030 if (p->end < addr)
1031 continue;
1032 if (p->flags & IORESOURCE_BUSY &&
1033 p->flags & IORESOURCE_EXCLUSIVE) {
1034 err = 1;
1035 break;
1036 }
1037 }
1038 read_unlock(&resource_lock);
1039
1040 return err;
1041}
1042
1043static int __init strict_iomem(char *str)
1044{
1045 if (strstr(str, "relaxed"))
1046 strict_iomem_checks = 0;
1047 if (strstr(str, "strict"))
1048 strict_iomem_checks = 1;
1049 return 1;
1050}
1051
1052__setup("iomem=", strict_iomem);