blob: 9b5f04404152c296af3a96132f27cfc80ffa9af9 [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
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>
Jiang Liu90e97822015-02-05 13:44:43 +080025#include <linux/resource_ext.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include <asm/io.h>
27
28
29struct resource ioport_resource = {
30 .name = "PCI IO",
Greg Kroah-Hartman6550e072006-06-12 17:11:31 -070031 .start = 0,
Linus Torvalds1da177e2005-04-16 15:20:36 -070032 .end = IO_SPACE_LIMIT,
33 .flags = IORESOURCE_IO,
34};
Linus Torvalds1da177e2005-04-16 15:20:36 -070035EXPORT_SYMBOL(ioport_resource);
36
37struct resource iomem_resource = {
38 .name = "PCI mem",
Greg Kroah-Hartman6550e072006-06-12 17:11:31 -070039 .start = 0,
40 .end = -1,
Linus Torvalds1da177e2005-04-16 15:20:36 -070041 .flags = IORESOURCE_MEM,
42};
Linus Torvalds1da177e2005-04-16 15:20:36 -070043EXPORT_SYMBOL(iomem_resource);
44
Ram Pai23c570a2011-07-05 23:44:30 -070045/* constraints to be met while allocating resources */
46struct 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
Linus Torvalds1da177e2005-04-16 15:20:36 -070053static DEFINE_RWLOCK(resource_lock);
54
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -070055/*
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 */
60static struct resource *bootmem_resource_free;
61static DEFINE_SPINLOCK(bootmem_resource_lock);
62
Vivek Goyal8c86e702014-08-08 14:25:50 -070063static struct resource *next_resource(struct resource *p, bool sibling_only)
Linus Torvalds1da177e2005-04-16 15:20:36 -070064{
Vivek Goyal8c86e702014-08-08 14:25:50 -070065 /* Caller wants to traverse through siblings only */
66 if (sibling_only)
67 return p->sibling;
68
Linus Torvalds1da177e2005-04-16 15:20:36 -070069 if (p->child)
70 return p->child;
71 while (!p->sibling && p->parent)
72 p = p->parent;
73 return p->sibling;
74}
75
Vivek Goyal8c86e702014-08-08 14:25:50 -070076static 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
Ingo Molnar13eb8372008-09-26 10:10:12 +020083#ifdef CONFIG_PROC_FS
84
85enum { MAX_IORES_LEVEL = 5 };
86
Linus Torvalds1da177e2005-04-16 15:20:36 -070087static 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
98static void r_stop(struct seq_file *m, void *v)
99 __releases(resource_lock)
100{
101 read_unlock(&resource_lock);
102}
103
104static int r_show(struct seq_file *m, void *v)
105{
106 struct resource *root = m->private;
107 struct resource *r = v, *p;
Linus Torvalds51d7b122016-04-14 12:05:37 -0700108 unsigned long long start, end;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109 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;
Linus Torvalds51d7b122016-04-14 12:05:37 -0700115
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
Greg Kroah-Hartman685143ac2006-06-12 15:18:31 -0700123 seq_printf(m, "%*s%0*llx-%0*llx : %s\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124 depth * 2, "",
Linus Torvalds51d7b122016-04-14 12:05:37 -0700125 width, start,
126 width, end,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127 r->name ? r->name : "<BAD>");
128 return 0;
129}
130
Helge Deller15ad7cd2006-12-06 20:40:36 -0800131static const struct seq_operations resource_op = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132 .start = r_start,
133 .next = r_next,
134 .stop = r_stop,
135 .show = r_show,
136};
137
138static 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
148static 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
Helge Deller15ad7cd2006-12-06 20:40:36 -0800158static const struct file_operations proc_ioports_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159 .open = ioports_open,
160 .read = seq_read,
161 .llseek = seq_lseek,
162 .release = seq_release,
163};
164
Helge Deller15ad7cd2006-12-06 20:40:36 -0800165static const struct file_operations proc_iomem_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166 .open = iomem_open,
167 .read = seq_read,
168 .llseek = seq_lseek,
169 .release = seq_release,
170};
171
172static int __init ioresources_init(void)
173{
Denis V. Lunevc33fff02008-04-29 01:02:31 -0700174 proc_create("ioports", 0, NULL, &proc_ioports_operations);
175 proc_create("iomem", 0, NULL, &proc_iomem_operations);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 return 0;
177}
178__initcall(ioresources_init);
179
180#endif /* CONFIG_PROC_FS */
181
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -0700182static 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
197static 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
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216/* Return the conflict entry if you can't request it */
217static struct resource * __request_resource(struct resource *root, struct resource *new)
218{
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700219 resource_size_t start = new->start;
220 resource_size_t end = new->end;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700221 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
Toshi Kaniff3cc952016-03-09 12:47:04 -0700245static int __release_resource(struct resource *old, bool release_child)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246{
Toshi Kaniff3cc952016-03-09 12:47:04 -0700247 struct resource *tmp, **p, *chd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248
249 p = &old->parent->child;
250 for (;;) {
251 tmp = *p;
252 if (!tmp)
253 break;
254 if (tmp == old) {
Toshi Kaniff3cc952016-03-09 12:47:04 -0700255 if (release_child || !(tmp->child)) {
256 *p = tmp->sibling;
257 } else {
258 for (chd = tmp->child;; chd = chd->sibling) {
259 chd->parent = tmp->parent;
260 if (!(chd->sibling))
261 break;
262 }
263 *p = tmp->child;
264 chd->sibling = tmp->sibling;
265 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266 old->parent = NULL;
267 return 0;
268 }
269 p = &tmp->sibling;
270 }
271 return -EINVAL;
272}
273
Yinghai Lu5eeec0e2009-12-22 15:02:22 -0800274static void __release_child_resources(struct resource *r)
275{
276 struct resource *tmp, *p;
277 resource_size_t size;
278
279 p = r->child;
280 r->child = NULL;
281 while (p) {
282 tmp = p;
283 p = p->sibling;
284
285 tmp->parent = NULL;
286 tmp->sibling = NULL;
287 __release_child_resources(tmp);
288
289 printk(KERN_DEBUG "release child resource %pR\n", tmp);
290 /* need to restore size, and keep flags */
291 size = resource_size(tmp);
292 tmp->start = 0;
293 tmp->end = size - 1;
294 }
295}
296
297void release_child_resources(struct resource *r)
298{
299 write_lock(&resource_lock);
300 __release_child_resources(r);
301 write_unlock(&resource_lock);
302}
303
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700304/**
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700305 * request_resource_conflict - request and reserve an I/O or memory resource
306 * @root: root resource descriptor
307 * @new: resource descriptor desired by caller
308 *
309 * Returns 0 for success, conflict resource on error.
310 */
311struct resource *request_resource_conflict(struct resource *root, struct resource *new)
312{
313 struct resource *conflict;
314
315 write_lock(&resource_lock);
316 conflict = __request_resource(root, new);
317 write_unlock(&resource_lock);
318 return conflict;
319}
320
321/**
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700322 * request_resource - request and reserve an I/O or memory resource
323 * @root: root resource descriptor
324 * @new: resource descriptor desired by caller
325 *
326 * Returns 0 for success, negative error code on error.
327 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328int request_resource(struct resource *root, struct resource *new)
329{
330 struct resource *conflict;
331
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700332 conflict = request_resource_conflict(root, new);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700333 return conflict ? -EBUSY : 0;
334}
335
336EXPORT_SYMBOL(request_resource);
337
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700338/**
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700339 * release_resource - release a previously reserved resource
340 * @old: resource pointer
341 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342int release_resource(struct resource *old)
343{
344 int retval;
345
346 write_lock(&resource_lock);
Toshi Kaniff3cc952016-03-09 12:47:04 -0700347 retval = __release_resource(old, true);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348 write_unlock(&resource_lock);
349 return retval;
350}
351
352EXPORT_SYMBOL(release_resource);
353
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700354/*
Toshi Kani3f336472016-01-26 21:57:29 +0100355 * Finds the lowest iomem resource existing within [res->start.res->end).
356 * The caller must specify res->start, res->end, res->flags, and optionally
Toshi Kania8fc4252016-01-26 21:57:32 +0100357 * desc. If found, returns 0, res is overwritten, if not found, returns -1.
Toshi Kani3f336472016-01-26 21:57:29 +0100358 * This function walks the whole tree and not just first level children until
359 * and unless first_level_children_only is true.
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700360 */
Toshi Kani3f336472016-01-26 21:57:29 +0100361static int find_next_iomem_res(struct resource *res, unsigned long desc,
Toshi Kania8fc4252016-01-26 21:57:32 +0100362 bool first_level_children_only)
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700363{
364 resource_size_t start, end;
365 struct resource *p;
Vivek Goyal8c86e702014-08-08 14:25:50 -0700366 bool sibling_only = false;
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700367
368 BUG_ON(!res);
369
370 start = res->start;
371 end = res->end;
KAMEZAWA Hiroyuki58c1b5b2006-08-05 12:15:01 -0700372 BUG_ON(start >= end);
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700373
Vivek Goyal800df622014-08-29 15:18:29 -0700374 if (first_level_children_only)
375 sibling_only = true;
376
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700377 read_lock(&resource_lock);
Vivek Goyal8c86e702014-08-08 14:25:50 -0700378
Vivek Goyal800df622014-08-29 15:18:29 -0700379 for (p = iomem_resource.child; p; p = next_resource(p, sibling_only)) {
Toshi Kania3650d52016-01-26 21:57:18 +0100380 if ((p->flags & res->flags) != res->flags)
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700381 continue;
Toshi Kani3f336472016-01-26 21:57:29 +0100382 if ((desc != IORES_DESC_NONE) && (desc != p->desc))
383 continue;
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700384 if (p->start > end) {
385 p = NULL;
386 break;
387 }
KAMEZAWA Hiroyuki58c1b5b2006-08-05 12:15:01 -0700388 if ((p->end >= start) && (p->start < end))
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700389 break;
390 }
Vivek Goyal8c86e702014-08-08 14:25:50 -0700391
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700392 read_unlock(&resource_lock);
393 if (!p)
394 return -1;
395 /* copy data */
KAMEZAWA Hiroyuki0f04ab52006-08-05 12:14:59 -0700396 if (res->start < p->start)
397 res->start = p->start;
398 if (res->end > p->end)
399 res->end = p->end;
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700400 return 0;
401}
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700402
403/*
Vivek Goyal8c86e702014-08-08 14:25:50 -0700404 * Walks through iomem resources and calls func() with matching resource
405 * ranges. This walks through whole tree and not just first level children.
406 * All the memory ranges which overlap start,end and also match flags and
Toshi Kani3f336472016-01-26 21:57:29 +0100407 * desc are valid candidates.
408 *
409 * @desc: I/O resource descriptor. Use IORES_DESC_NONE to skip @desc check.
410 * @flags: I/O resource flags
411 * @start: start addr
412 * @end: end addr
413 *
414 * NOTE: For a new descriptor search, define a new IORES_DESC in
415 * <linux/ioport.h> and set it in 'desc' of a target resource entry.
416 */
417int walk_iomem_res_desc(unsigned long desc, unsigned long flags, u64 start,
418 u64 end, void *arg, int (*func)(u64, u64, void *))
419{
420 struct resource res;
421 u64 orig_end;
422 int ret = -1;
423
424 res.start = start;
425 res.end = end;
426 res.flags = flags;
427 orig_end = res.end;
428
429 while ((res.start < res.end) &&
Toshi Kania8fc4252016-01-26 21:57:32 +0100430 (!find_next_iomem_res(&res, desc, false))) {
Toshi Kani3f336472016-01-26 21:57:29 +0100431
432 ret = (*func)(res.start, res.end, arg);
433 if (ret)
434 break;
435
436 res.start = res.end + 1;
437 res.end = orig_end;
438 }
439
440 return ret;
441}
442
443/*
Toshi Kanibd7e6cb2016-01-26 21:57:26 +0100444 * This function calls the @func callback against all memory ranges of type
445 * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY.
446 * Now, this function is only for System RAM, it deals with full ranges and
447 * not PFNs. If resources are not PFN-aligned, dealing with PFNs can truncate
448 * ranges.
Vivek Goyal8c86e702014-08-08 14:25:50 -0700449 */
450int walk_system_ram_res(u64 start, u64 end, void *arg,
451 int (*func)(u64, u64, void *))
452{
453 struct resource res;
454 u64 orig_end;
455 int ret = -1;
456
457 res.start = start;
458 res.end = end;
Toshi Kanibd7e6cb2016-01-26 21:57:26 +0100459 res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
Vivek Goyal8c86e702014-08-08 14:25:50 -0700460 orig_end = res.end;
461 while ((res.start < res.end) &&
Toshi Kania8fc4252016-01-26 21:57:32 +0100462 (!find_next_iomem_res(&res, IORES_DESC_NONE, true))) {
Vivek Goyal8c86e702014-08-08 14:25:50 -0700463 ret = (*func)(res.start, res.end, arg);
464 if (ret)
465 break;
466 res.start = res.end + 1;
467 res.end = orig_end;
468 }
469 return ret;
470}
471
472#if !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
473
474/*
Toshi Kanibd7e6cb2016-01-26 21:57:26 +0100475 * This function calls the @func callback against all memory ranges of type
476 * System RAM which are marked as IORESOURCE_SYSTEM_RAM and IORESOUCE_BUSY.
477 * It is to be used only for System RAM.
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700478 */
479int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
480 void *arg, int (*func)(unsigned long, unsigned long, void *))
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700481{
482 struct resource res;
Wu Fengguang37b99dd2010-03-01 21:55:51 +0800483 unsigned long pfn, end_pfn;
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700484 u64 orig_end;
485 int ret = -1;
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700486
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700487 res.start = (u64) start_pfn << PAGE_SHIFT;
488 res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1;
Toshi Kanibd7e6cb2016-01-26 21:57:26 +0100489 res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700490 orig_end = res.end;
KAMEZAWA Hiroyuki908eedc2009-09-22 16:45:46 -0700491 while ((res.start < res.end) &&
Toshi Kania8fc4252016-01-26 21:57:32 +0100492 (find_next_iomem_res(&res, IORES_DESC_NONE, true) >= 0)) {
Wu Fengguang37b99dd2010-03-01 21:55:51 +0800493 pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT;
494 end_pfn = (res.end + 1) >> PAGE_SHIFT;
495 if (end_pfn > pfn)
H. Peter Anvinf4149662010-03-02 11:21:09 -0800496 ret = (*func)(pfn, end_pfn - pfn, arg);
KAMEZAWA Hiroyuki75884fb2007-10-16 01:26:10 -0700497 if (ret)
498 break;
499 res.start = res.end + 1;
500 res.end = orig_end;
501 }
502 return ret;
503}
504
KAMEZAWA Hiroyuki2842f112006-06-27 02:53:36 -0700505#endif
506
Wu Fengguang61ef2482010-01-22 16:16:19 +0800507static int __is_ram(unsigned long pfn, unsigned long nr_pages, void *arg)
508{
509 return 1;
510}
511/*
512 * This generic page_is_ram() returns true if specified address is
Toshi Kanibd7e6cb2016-01-26 21:57:26 +0100513 * registered as System RAM in iomem_resource list.
Wu Fengguang61ef2482010-01-22 16:16:19 +0800514 */
Andrew Mortone5273002010-01-26 16:31:19 -0800515int __weak page_is_ram(unsigned long pfn)
Wu Fengguang61ef2482010-01-22 16:16:19 +0800516{
517 return walk_system_ram_range(pfn, 1, NULL, __is_ram) == 1;
518}
Chen Gongc5a13032013-06-06 15:20:51 -0700519EXPORT_SYMBOL_GPL(page_is_ram);
Wu Fengguang61ef2482010-01-22 16:16:19 +0800520
Dan Williams124fe202015-08-10 23:07:05 -0400521/**
522 * region_intersects() - determine intersection of region with known resources
523 * @start: region start address
524 * @size: size of region
Toshi Kani1c29f252016-01-26 21:57:28 +0100525 * @flags: flags of resource (in iomem_resource)
526 * @desc: descriptor of resource (in iomem_resource) or IORES_DESC_NONE
Mike Travis67cf13c2014-10-13 15:54:03 -0700527 *
Dan Williams124fe202015-08-10 23:07:05 -0400528 * Check if the specified region partially overlaps or fully eclipses a
Toshi Kani1c29f252016-01-26 21:57:28 +0100529 * resource identified by @flags and @desc (optional with IORES_DESC_NONE).
530 * Return REGION_DISJOINT if the region does not overlap @flags/@desc,
531 * return REGION_MIXED if the region overlaps @flags/@desc and another
532 * resource, and return REGION_INTERSECTS if the region overlaps @flags/@desc
533 * and no other defined resource. Note that REGION_INTERSECTS is also
534 * returned in the case when the specified region overlaps RAM and undefined
535 * memory holes.
Dan Williams124fe202015-08-10 23:07:05 -0400536 *
537 * region_intersect() is used by memory remapping functions to ensure
538 * the user is not remapping RAM and is a vast speed up over walking
539 * through the resource table page by page.
Mike Travis67cf13c2014-10-13 15:54:03 -0700540 */
Toshi Kani1c29f252016-01-26 21:57:28 +0100541int region_intersects(resource_size_t start, size_t size, unsigned long flags,
542 unsigned long desc)
Mike Travis67cf13c2014-10-13 15:54:03 -0700543{
Dan Williams124fe202015-08-10 23:07:05 -0400544 resource_size_t end = start + size - 1;
545 int type = 0; int other = 0;
546 struct resource *p;
Mike Travis67cf13c2014-10-13 15:54:03 -0700547
548 read_lock(&resource_lock);
549 for (p = iomem_resource.child; p ; p = p->sibling) {
Toshi Kani1c29f252016-01-26 21:57:28 +0100550 bool is_type = (((p->flags & flags) == flags) &&
551 ((desc == IORES_DESC_NONE) ||
552 (desc == p->desc)));
Mike Travis67cf13c2014-10-13 15:54:03 -0700553
Dan Williams124fe202015-08-10 23:07:05 -0400554 if (start >= p->start && start <= p->end)
555 is_type ? type++ : other++;
556 if (end >= p->start && end <= p->end)
557 is_type ? type++ : other++;
558 if (p->start >= start && p->end <= end)
559 is_type ? type++ : other++;
Mike Travis67cf13c2014-10-13 15:54:03 -0700560 }
561 read_unlock(&resource_lock);
Dan Williams124fe202015-08-10 23:07:05 -0400562
563 if (other == 0)
564 return type ? REGION_INTERSECTS : REGION_DISJOINT;
565
566 if (type)
567 return REGION_MIXED;
568
569 return REGION_DISJOINT;
Mike Travis67cf13c2014-10-13 15:54:03 -0700570}
Toshi Kani1c29f252016-01-26 21:57:28 +0100571EXPORT_SYMBOL_GPL(region_intersects);
Mike Travis67cf13c2014-10-13 15:54:03 -0700572
Bjorn Helgaasfcb11912010-12-16 10:38:46 -0700573void __weak arch_remove_reservations(struct resource *avail)
574{
575}
576
Bjorn Helgaasa9cea012010-10-26 15:41:13 -0600577static resource_size_t simple_align_resource(void *data,
578 const struct resource *avail,
579 resource_size_t size,
580 resource_size_t align)
581{
582 return avail->start;
583}
584
Bjorn Helgaas5d6b1fa2010-10-26 15:41:18 -0600585static void resource_clip(struct resource *res, resource_size_t min,
586 resource_size_t max)
587{
588 if (res->start < min)
589 res->start = min;
590 if (res->end > max)
591 res->end = max;
592}
593
Linus Torvalds1da177e2005-04-16 15:20:36 -0700594/*
Ram Pai23c570a2011-07-05 23:44:30 -0700595 * Find empty slot in the resource tree with the given range and
596 * alignment constraints
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 */
Ram Pai23c570a2011-07-05 23:44:30 -0700598static int __find_resource(struct resource *root, struct resource *old,
599 struct resource *new,
600 resource_size_t size,
601 struct resource_constraint *constraint)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602{
603 struct resource *this = root->child;
Bjorn Helgaasa1862e32010-10-26 15:41:28 -0600604 struct resource tmp = *new, avail, alloc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605
Dominik Brodowski0e2c8b82009-12-20 10:50:02 +0100606 tmp.start = root->start;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607 /*
Bjorn Helgaasc0f5ac52010-12-16 10:38:41 -0700608 * Skip past an allocated resource that starts at 0, since the assignment
609 * of this->start - 1 to tmp->end below would cause an underflow.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610 */
Ram Pai23c570a2011-07-05 23:44:30 -0700611 if (this && this->start == root->start) {
612 tmp.start = (this == old) ? old->start : this->end + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 this = this->sibling;
614 }
Bjorn Helgaasc0f5ac52010-12-16 10:38:41 -0700615 for(;;) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616 if (this)
Ram Pai23c570a2011-07-05 23:44:30 -0700617 tmp.end = (this == old) ? this->end : this->start - 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618 else
Dominik Brodowski0e2c8b82009-12-20 10:50:02 +0100619 tmp.end = root->end;
Bjorn Helgaas5d6b1fa2010-10-26 15:41:18 -0600620
Ram Pai47ea91b2011-09-22 15:48:58 +0800621 if (tmp.end < tmp.start)
622 goto next;
623
Ram Pai23c570a2011-07-05 23:44:30 -0700624 resource_clip(&tmp, constraint->min, constraint->max);
Bjorn Helgaasfcb11912010-12-16 10:38:46 -0700625 arch_remove_reservations(&tmp);
Bjorn Helgaasa9cea012010-10-26 15:41:13 -0600626
Bjorn Helgaasa1862e32010-10-26 15:41:28 -0600627 /* Check for overflow after ALIGN() */
Ram Pai23c570a2011-07-05 23:44:30 -0700628 avail.start = ALIGN(tmp.start, constraint->align);
Bjorn Helgaasa1862e32010-10-26 15:41:28 -0600629 avail.end = tmp.end;
Bjorn Helgaas5edb93b2014-02-04 19:32:28 -0800630 avail.flags = new->flags & ~IORESOURCE_UNSET;
Bjorn Helgaasa1862e32010-10-26 15:41:28 -0600631 if (avail.start >= tmp.start) {
Bjorn Helgaas5edb93b2014-02-04 19:32:28 -0800632 alloc.flags = avail.flags;
Ram Pai23c570a2011-07-05 23:44:30 -0700633 alloc.start = constraint->alignf(constraint->alignf_data, &avail,
634 size, constraint->align);
Bjorn Helgaasa1862e32010-10-26 15:41:28 -0600635 alloc.end = alloc.start + size - 1;
636 if (resource_contains(&avail, &alloc)) {
637 new->start = alloc.start;
638 new->end = alloc.end;
639 return 0;
640 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641 }
Ram Pai47ea91b2011-09-22 15:48:58 +0800642
643next: if (!this || this->end == root->end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700644 break;
Ram Pai47ea91b2011-09-22 15:48:58 +0800645
Ram Pai23c570a2011-07-05 23:44:30 -0700646 if (this != old)
647 tmp.start = this->end + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700648 this = this->sibling;
649 }
650 return -EBUSY;
651}
652
Ram Pai23c570a2011-07-05 23:44:30 -0700653/*
654 * Find empty slot in the resource tree given range and alignment.
655 */
656static int find_resource(struct resource *root, struct resource *new,
657 resource_size_t size,
658 struct resource_constraint *constraint)
659{
660 return __find_resource(root, NULL, new, size, constraint);
661}
662
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700663/**
Ram Pai23c570a2011-07-05 23:44:30 -0700664 * reallocate_resource - allocate a slot in the resource tree given range & alignment.
665 * The resource will be relocated if the new size cannot be reallocated in the
666 * current location.
667 *
668 * @root: root resource descriptor
669 * @old: resource descriptor desired by caller
670 * @newsize: new size of the resource descriptor
671 * @constraint: the size and alignment constraints to be met.
672 */
Daeseok Youn28ab49f2014-04-03 14:48:36 -0700673static int reallocate_resource(struct resource *root, struct resource *old,
Ram Pai23c570a2011-07-05 23:44:30 -0700674 resource_size_t newsize,
675 struct resource_constraint *constraint)
676{
677 int err=0;
678 struct resource new = *old;
679 struct resource *conflict;
680
681 write_lock(&resource_lock);
682
683 if ((err = __find_resource(root, old, &new, newsize, constraint)))
684 goto out;
685
686 if (resource_contains(&new, old)) {
687 old->start = new.start;
688 old->end = new.end;
689 goto out;
690 }
691
692 if (old->child) {
693 err = -EBUSY;
694 goto out;
695 }
696
697 if (resource_contains(old, &new)) {
698 old->start = new.start;
699 old->end = new.end;
700 } else {
Toshi Kaniff3cc952016-03-09 12:47:04 -0700701 __release_resource(old, true);
Ram Pai23c570a2011-07-05 23:44:30 -0700702 *old = new;
703 conflict = __request_resource(root, old);
704 BUG_ON(conflict);
705 }
706out:
707 write_unlock(&resource_lock);
708 return err;
709}
710
711
712/**
713 * allocate_resource - allocate empty slot in the resource tree given range & alignment.
714 * The resource will be reallocated with a new size if it was already allocated
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700715 * @root: root resource descriptor
716 * @new: resource descriptor desired by caller
717 * @size: requested resource region size
Wei Yangee5e5682012-05-31 16:26:05 -0700718 * @min: minimum boundary to allocate
719 * @max: maximum boundary to allocate
Randy Dunlape1ca66d2006-10-03 01:13:51 -0700720 * @align: alignment requested, in bytes
721 * @alignf: alignment function, optional, called if not NULL
722 * @alignf_data: arbitrary data to pass to the @alignf function
Linus Torvalds1da177e2005-04-16 15:20:36 -0700723 */
724int allocate_resource(struct resource *root, struct resource *new,
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700725 resource_size_t size, resource_size_t min,
726 resource_size_t max, resource_size_t align,
Dominik Brodowskib26b2d42010-01-01 17:40:49 +0100727 resource_size_t (*alignf)(void *,
Dominik Brodowski3b7a17f2010-01-01 17:40:50 +0100728 const struct resource *,
Dominik Brodowskib26b2d42010-01-01 17:40:49 +0100729 resource_size_t,
730 resource_size_t),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731 void *alignf_data)
732{
733 int err;
Ram Pai23c570a2011-07-05 23:44:30 -0700734 struct resource_constraint constraint;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700735
Bjorn Helgaasa9cea012010-10-26 15:41:13 -0600736 if (!alignf)
737 alignf = simple_align_resource;
738
Ram Pai23c570a2011-07-05 23:44:30 -0700739 constraint.min = min;
740 constraint.max = max;
741 constraint.align = align;
742 constraint.alignf = alignf;
743 constraint.alignf_data = alignf_data;
744
745 if ( new->parent ) {
746 /* resource is already allocated, try reallocating with
747 the new constraints */
748 return reallocate_resource(root, new, size, &constraint);
749 }
750
Linus Torvalds1da177e2005-04-16 15:20:36 -0700751 write_lock(&resource_lock);
Ram Pai23c570a2011-07-05 23:44:30 -0700752 err = find_resource(root, new, size, &constraint);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753 if (err >= 0 && __request_resource(root, new))
754 err = -EBUSY;
755 write_unlock(&resource_lock);
756 return err;
757}
758
759EXPORT_SYMBOL(allocate_resource);
760
Geert Uytterhoeven1c388912011-05-07 20:53:16 +0200761/**
762 * lookup_resource - find an existing resource by a resource start address
763 * @root: root resource descriptor
764 * @start: resource start address
765 *
766 * Returns a pointer to the resource if found, NULL otherwise
767 */
768struct resource *lookup_resource(struct resource *root, resource_size_t start)
769{
770 struct resource *res;
771
772 read_lock(&resource_lock);
773 for (res = root->child; res; res = res->sibling) {
774 if (res->start == start)
775 break;
776 }
777 read_unlock(&resource_lock);
778
779 return res;
780}
781
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700782/*
783 * Insert a resource into the resource tree. If successful, return NULL,
784 * otherwise return the conflicting resource (compare to __request_resource())
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785 */
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700786static struct resource * __insert_resource(struct resource *parent, struct resource *new)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700787{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700788 struct resource *first, *next;
789
Matthew Wilcoxd33b6fb2006-06-30 02:31:24 -0700790 for (;; parent = first) {
Matthew Wilcoxd33b6fb2006-06-30 02:31:24 -0700791 first = __request_resource(parent, new);
792 if (!first)
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700793 return first;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794
Matthew Wilcoxd33b6fb2006-06-30 02:31:24 -0700795 if (first == parent)
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700796 return first;
Huang Shijie5de1cb22010-10-27 15:34:52 -0700797 if (WARN_ON(first == new)) /* duplicated insertion */
798 return first;
Matthew Wilcoxd33b6fb2006-06-30 02:31:24 -0700799
800 if ((first->start > new->start) || (first->end < new->end))
801 break;
802 if ((first->start == new->start) && (first->end == new->end))
803 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804 }
805
806 for (next = first; ; next = next->sibling) {
807 /* Partial overlap? Bad, and unfixable */
808 if (next->start < new->start || next->end > new->end)
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700809 return next;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810 if (!next->sibling)
811 break;
812 if (next->sibling->start > new->end)
813 break;
814 }
815
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816 new->parent = parent;
817 new->sibling = next->sibling;
818 new->child = first;
819
820 next->sibling = NULL;
821 for (next = first; next; next = next->sibling)
822 next->parent = new;
823
824 if (parent->child == first) {
825 parent->child = new;
826 } else {
827 next = parent->child;
828 while (next->sibling != first)
829 next = next->sibling;
830 next->sibling = new;
831 }
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700832 return NULL;
833}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700835/**
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700836 * insert_resource_conflict - Inserts resource in the resource tree
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700837 * @parent: parent of the new resource
838 * @new: new resource to insert
839 *
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700840 * Returns 0 on success, conflict resource if the resource can't be inserted.
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700841 *
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700842 * This function is equivalent to request_resource_conflict when no conflict
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700843 * happens. If a conflict happens, and the conflicting resources
844 * entirely fit within the range of the new resource, then the new
845 * resource is inserted and the conflicting resources become children of
846 * the new resource.
Toshi Kaniff3cc952016-03-09 12:47:04 -0700847 *
848 * This function is intended for producers of resources, such as FW modules
849 * and bus drivers.
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700850 */
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700851struct resource *insert_resource_conflict(struct resource *parent, struct resource *new)
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700852{
853 struct resource *conflict;
854
855 write_lock(&resource_lock);
856 conflict = __insert_resource(parent, new);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857 write_unlock(&resource_lock);
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700858 return conflict;
859}
860
861/**
862 * insert_resource - Inserts a resource in the resource tree
863 * @parent: parent of the new resource
864 * @new: new resource to insert
865 *
866 * Returns 0 on success, -EBUSY if the resource can't be inserted.
Toshi Kaniff3cc952016-03-09 12:47:04 -0700867 *
868 * This function is intended for producers of resources, such as FW modules
869 * and bus drivers.
Bjorn Helgaas66f12072010-03-11 17:01:09 -0700870 */
871int insert_resource(struct resource *parent, struct resource *new)
872{
873 struct resource *conflict;
874
875 conflict = insert_resource_conflict(parent, new);
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700876 return conflict ? -EBUSY : 0;
877}
Toshi Kani8095d0f2016-03-09 12:47:05 -0700878EXPORT_SYMBOL_GPL(insert_resource);
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700879
880/**
881 * insert_resource_expand_to_fit - Insert a resource into the resource tree
Randy Dunlap6781f4a2008-08-31 20:31:55 -0700882 * @root: root resource descriptor
Linus Torvaldsbef69ea2008-08-29 20:18:31 -0700883 * @new: new resource to insert
884 *
885 * Insert a resource into the resource tree, possibly expanding it in order
886 * to make it encompass any conflicting resources.
887 */
888void insert_resource_expand_to_fit(struct resource *root, struct resource *new)
889{
890 if (new->parent)
891 return;
892
893 write_lock(&resource_lock);
894 for (;;) {
895 struct resource *conflict;
896
897 conflict = __insert_resource(root, new);
898 if (!conflict)
899 break;
900 if (conflict == root)
901 break;
902
903 /* Ok, expand resource to cover the conflict, then try again .. */
904 if (conflict->start < new->start)
905 new->start = conflict->start;
906 if (conflict->end > new->end)
907 new->end = conflict->end;
908
909 printk("Expanded resource %s due to conflict with %s\n", new->name, conflict->name);
910 }
911 write_unlock(&resource_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700912}
913
Toshi Kaniff3cc952016-03-09 12:47:04 -0700914/**
915 * remove_resource - Remove a resource in the resource tree
916 * @old: resource to remove
917 *
918 * Returns 0 on success, -EINVAL if the resource is not valid.
919 *
920 * This function removes a resource previously inserted by insert_resource()
921 * or insert_resource_conflict(), and moves the children (if any) up to
922 * where they were before. insert_resource() and insert_resource_conflict()
923 * insert a new resource, and move any conflicting resources down to the
924 * children of the new resource.
925 *
926 * insert_resource(), insert_resource_conflict() and remove_resource() are
927 * intended for producers of resources, such as FW modules and bus drivers.
928 */
929int remove_resource(struct resource *old)
930{
931 int retval;
932
933 write_lock(&resource_lock);
934 retval = __release_resource(old, false);
935 write_unlock(&resource_lock);
936 return retval;
937}
Toshi Kani8095d0f2016-03-09 12:47:05 -0700938EXPORT_SYMBOL_GPL(remove_resource);
Toshi Kaniff3cc952016-03-09 12:47:04 -0700939
Toshi Kaniae8e3a92013-04-29 15:08:17 -0700940static int __adjust_resource(struct resource *res, resource_size_t start,
941 resource_size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700942{
943 struct resource *tmp, *parent = res->parent;
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -0700944 resource_size_t end = start + size - 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945 int result = -EBUSY;
946
Yinghai Lu82ec90e2012-05-17 18:51:11 -0700947 if (!parent)
948 goto skip;
949
Linus Torvalds1da177e2005-04-16 15:20:36 -0700950 if ((start < parent->start) || (end > parent->end))
951 goto out;
952
Linus Torvalds1da177e2005-04-16 15:20:36 -0700953 if (res->sibling && (res->sibling->start <= end))
954 goto out;
955
956 tmp = parent->child;
957 if (tmp != res) {
958 while (tmp->sibling != res)
959 tmp = tmp->sibling;
960 if (start <= tmp->end)
961 goto out;
962 }
963
Yinghai Lu82ec90e2012-05-17 18:51:11 -0700964skip:
965 for (tmp = res->child; tmp; tmp = tmp->sibling)
966 if ((tmp->start < start) || (tmp->end > end))
967 goto out;
968
Linus Torvalds1da177e2005-04-16 15:20:36 -0700969 res->start = start;
970 res->end = end;
971 result = 0;
972
973 out:
Toshi Kaniae8e3a92013-04-29 15:08:17 -0700974 return result;
975}
976
977/**
978 * adjust_resource - modify a resource's start and size
979 * @res: resource to modify
980 * @start: new start value
981 * @size: new size
982 *
983 * Given an existing resource, change its start and size to match the
984 * arguments. Returns 0 on success, -EBUSY if it can't fit.
985 * Existing children of the resource are assumed to be immutable.
986 */
987int adjust_resource(struct resource *res, resource_size_t start,
988 resource_size_t size)
989{
990 int result;
991
992 write_lock(&resource_lock);
993 result = __adjust_resource(res, start, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700994 write_unlock(&resource_lock);
995 return result;
996}
Cong Wang24105742012-02-03 21:42:39 +0800997EXPORT_SYMBOL(adjust_resource);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700998
Yinghai Lu268364a2008-09-04 21:02:44 +0200999static void __init __reserve_region_with_split(struct resource *root,
1000 resource_size_t start, resource_size_t end,
1001 const char *name)
1002{
1003 struct resource *parent = root;
1004 struct resource *conflict;
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -07001005 struct resource *res = alloc_resource(GFP_ATOMIC);
T Makphaibulchoke4965f562012-10-04 17:16:55 -07001006 struct resource *next_res = NULL;
Yinghai Lu268364a2008-09-04 21:02:44 +02001007
1008 if (!res)
1009 return;
1010
1011 res->name = name;
1012 res->start = start;
1013 res->end = end;
1014 res->flags = IORESOURCE_BUSY;
Toshi Kani43ee4932016-01-26 21:57:19 +01001015 res->desc = IORES_DESC_NONE;
Yinghai Lu268364a2008-09-04 21:02:44 +02001016
T Makphaibulchoke4965f562012-10-04 17:16:55 -07001017 while (1) {
Yinghai Lu268364a2008-09-04 21:02:44 +02001018
T Makphaibulchoke4965f562012-10-04 17:16:55 -07001019 conflict = __request_resource(parent, res);
1020 if (!conflict) {
1021 if (!next_res)
1022 break;
1023 res = next_res;
1024 next_res = NULL;
1025 continue;
1026 }
Yinghai Lu268364a2008-09-04 21:02:44 +02001027
T Makphaibulchoke4965f562012-10-04 17:16:55 -07001028 /* conflict covered whole area */
1029 if (conflict->start <= res->start &&
1030 conflict->end >= res->end) {
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -07001031 free_resource(res);
T Makphaibulchoke4965f562012-10-04 17:16:55 -07001032 WARN_ON(next_res);
1033 break;
1034 }
Yinghai Lu268364a2008-09-04 21:02:44 +02001035
T Makphaibulchoke4965f562012-10-04 17:16:55 -07001036 /* failed, split and try again */
1037 if (conflict->start > res->start) {
1038 end = res->end;
1039 res->end = conflict->start - 1;
1040 if (conflict->end < end) {
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -07001041 next_res = alloc_resource(GFP_ATOMIC);
T Makphaibulchoke4965f562012-10-04 17:16:55 -07001042 if (!next_res) {
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -07001043 free_resource(res);
T Makphaibulchoke4965f562012-10-04 17:16:55 -07001044 break;
1045 }
1046 next_res->name = name;
1047 next_res->start = conflict->end + 1;
1048 next_res->end = end;
1049 next_res->flags = IORESOURCE_BUSY;
Toshi Kani43ee4932016-01-26 21:57:19 +01001050 next_res->desc = IORES_DESC_NONE;
T Makphaibulchoke4965f562012-10-04 17:16:55 -07001051 }
1052 } else {
1053 res->start = conflict->end + 1;
1054 }
1055 }
1056
Yinghai Lu268364a2008-09-04 21:02:44 +02001057}
1058
Paul Mundtbea92112008-10-22 19:31:11 +09001059void __init reserve_region_with_split(struct resource *root,
Yinghai Lu268364a2008-09-04 21:02:44 +02001060 resource_size_t start, resource_size_t end,
1061 const char *name)
1062{
Octavian Purdila65fed8f2012-07-30 14:42:58 -07001063 int abort = 0;
1064
Yinghai Lu268364a2008-09-04 21:02:44 +02001065 write_lock(&resource_lock);
Octavian Purdila65fed8f2012-07-30 14:42:58 -07001066 if (root->start > start || root->end < end) {
1067 pr_err("requested range [0x%llx-0x%llx] not in root %pr\n",
1068 (unsigned long long)start, (unsigned long long)end,
1069 root);
1070 if (start > root->end || end < root->start)
1071 abort = 1;
1072 else {
1073 if (end > root->end)
1074 end = root->end;
1075 if (start < root->start)
1076 start = root->start;
1077 pr_err("fixing request to [0x%llx-0x%llx]\n",
1078 (unsigned long long)start,
1079 (unsigned long long)end);
1080 }
1081 dump_stack();
1082 }
1083 if (!abort)
1084 __reserve_region_with_split(root, start, end, name);
Yinghai Lu268364a2008-09-04 21:02:44 +02001085 write_unlock(&resource_lock);
1086}
1087
Ivan Kokshaysky88452562008-03-30 19:50:14 +04001088/**
1089 * resource_alignment - calculate resource's alignment
1090 * @res: resource pointer
1091 *
1092 * Returns alignment on success, 0 (invalid alignment) on failure.
1093 */
1094resource_size_t resource_alignment(struct resource *res)
1095{
1096 switch (res->flags & (IORESOURCE_SIZEALIGN | IORESOURCE_STARTALIGN)) {
1097 case IORESOURCE_SIZEALIGN:
Magnus Damm1a4e5642008-07-29 22:32:57 -07001098 return resource_size(res);
Ivan Kokshaysky88452562008-03-30 19:50:14 +04001099 case IORESOURCE_STARTALIGN:
1100 return res->start;
1101 default:
1102 return 0;
1103 }
1104}
1105
Linus Torvalds1da177e2005-04-16 15:20:36 -07001106/*
1107 * This is compatibility stuff for IO resources.
1108 *
1109 * Note how this, unlike the above, knows about
1110 * the IO flag meanings (busy etc).
1111 *
Randy Dunlape1ca66d2006-10-03 01:13:51 -07001112 * request_region creates a new busy region.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001113 *
Randy Dunlape1ca66d2006-10-03 01:13:51 -07001114 * release_region releases a matching busy region.
1115 */
1116
Alan Cox8b6d0432010-03-29 19:38:00 +02001117static DECLARE_WAIT_QUEUE_HEAD(muxed_resource_wait);
1118
Randy Dunlape1ca66d2006-10-03 01:13:51 -07001119/**
1120 * __request_region - create a new busy resource region
1121 * @parent: parent resource descriptor
1122 * @start: resource start address
1123 * @n: resource region size
1124 * @name: reserving caller's ID string
Randy Dunlap6ae301e2009-01-15 13:51:01 -08001125 * @flags: IO resource flags
Linus Torvalds1da177e2005-04-16 15:20:36 -07001126 */
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -07001127struct resource * __request_region(struct resource *parent,
1128 resource_size_t start, resource_size_t n,
Arjan van de Vene8de1482008-10-22 19:55:31 -07001129 const char *name, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001130{
Alan Cox8b6d0432010-03-29 19:38:00 +02001131 DECLARE_WAITQUEUE(wait, current);
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -07001132 struct resource *res = alloc_resource(GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001133
Bjorn Helgaasc26ec882008-10-15 22:05:14 -07001134 if (!res)
1135 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001136
Bjorn Helgaasc26ec882008-10-15 22:05:14 -07001137 res->name = name;
1138 res->start = start;
1139 res->end = start + n - 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001140
Bjorn Helgaasc26ec882008-10-15 22:05:14 -07001141 write_lock(&resource_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001142
Bjorn Helgaasc26ec882008-10-15 22:05:14 -07001143 for (;;) {
1144 struct resource *conflict;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001145
Toshi Kani4e0d8f7e2016-03-09 12:47:03 -07001146 res->flags = resource_type(parent) | resource_ext_type(parent);
1147 res->flags |= IORESOURCE_BUSY | flags;
1148 res->desc = parent->desc;
1149
Bjorn Helgaasc26ec882008-10-15 22:05:14 -07001150 conflict = __request_resource(parent, res);
1151 if (!conflict)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001152 break;
Bjorn Helgaasc26ec882008-10-15 22:05:14 -07001153 if (conflict != parent) {
Simon Guinot59ceeaa2015-09-10 00:15:18 +02001154 if (!(conflict->flags & IORESOURCE_BUSY)) {
1155 parent = conflict;
Bjorn Helgaasc26ec882008-10-15 22:05:14 -07001156 continue;
Simon Guinot59ceeaa2015-09-10 00:15:18 +02001157 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001158 }
Alan Cox8b6d0432010-03-29 19:38:00 +02001159 if (conflict->flags & flags & IORESOURCE_MUXED) {
1160 add_wait_queue(&muxed_resource_wait, &wait);
1161 write_unlock(&resource_lock);
1162 set_current_state(TASK_UNINTERRUPTIBLE);
1163 schedule();
1164 remove_wait_queue(&muxed_resource_wait, &wait);
1165 write_lock(&resource_lock);
1166 continue;
1167 }
Bjorn Helgaasc26ec882008-10-15 22:05:14 -07001168 /* Uhhuh, that didn't work out.. */
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -07001169 free_resource(res);
Bjorn Helgaasc26ec882008-10-15 22:05:14 -07001170 res = NULL;
1171 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001172 }
Bjorn Helgaasc26ec882008-10-15 22:05:14 -07001173 write_unlock(&resource_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001174 return res;
1175}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001176EXPORT_SYMBOL(__request_region);
1177
Randy Dunlape1ca66d2006-10-03 01:13:51 -07001178/**
Randy Dunlape1ca66d2006-10-03 01:13:51 -07001179 * __release_region - release a previously reserved resource region
1180 * @parent: parent resource descriptor
1181 * @start: resource start address
1182 * @n: resource region size
1183 *
1184 * The described resource region must match a currently busy region.
1185 */
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -07001186void __release_region(struct resource *parent, resource_size_t start,
1187 resource_size_t n)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001188{
1189 struct resource **p;
Greg Kroah-Hartmand75fc8b2006-06-12 16:09:23 -07001190 resource_size_t end;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001191
1192 p = &parent->child;
1193 end = start + n - 1;
1194
1195 write_lock(&resource_lock);
1196
1197 for (;;) {
1198 struct resource *res = *p;
1199
1200 if (!res)
1201 break;
1202 if (res->start <= start && res->end >= end) {
1203 if (!(res->flags & IORESOURCE_BUSY)) {
1204 p = &res->child;
1205 continue;
1206 }
1207 if (res->start != start || res->end != end)
1208 break;
1209 *p = res->sibling;
1210 write_unlock(&resource_lock);
Alan Cox8b6d0432010-03-29 19:38:00 +02001211 if (res->flags & IORESOURCE_MUXED)
1212 wake_up(&muxed_resource_wait);
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -07001213 free_resource(res);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001214 return;
1215 }
1216 p = &res->sibling;
1217 }
1218
1219 write_unlock(&resource_lock);
1220
Greg Kroah-Hartman685143ac2006-06-12 15:18:31 -07001221 printk(KERN_WARNING "Trying to free nonexistent resource "
1222 "<%016llx-%016llx>\n", (unsigned long long)start,
1223 (unsigned long long)end);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001224}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001225EXPORT_SYMBOL(__release_region);
1226
Toshi Kani825f7872013-04-29 15:08:19 -07001227#ifdef CONFIG_MEMORY_HOTREMOVE
1228/**
1229 * release_mem_region_adjustable - release a previously reserved memory region
1230 * @parent: parent resource descriptor
1231 * @start: resource start address
1232 * @size: resource region size
1233 *
1234 * This interface is intended for memory hot-delete. The requested region
1235 * is released from a currently busy memory resource. The requested region
1236 * must either match exactly or fit into a single busy resource entry. In
1237 * the latter case, the remaining resource is adjusted accordingly.
1238 * Existing children of the busy memory resource must be immutable in the
1239 * request.
1240 *
1241 * Note:
1242 * - Additional release conditions, such as overlapping region, can be
1243 * supported after they are confirmed as valid cases.
1244 * - When a busy memory resource gets split into two entries, the code
1245 * assumes that all children remain in the lower address entry for
1246 * simplicity. Enhance this logic when necessary.
1247 */
1248int release_mem_region_adjustable(struct resource *parent,
1249 resource_size_t start, resource_size_t size)
1250{
1251 struct resource **p;
1252 struct resource *res;
1253 struct resource *new_res;
1254 resource_size_t end;
1255 int ret = -EINVAL;
1256
1257 end = start + size - 1;
1258 if ((start < parent->start) || (end > parent->end))
1259 return ret;
1260
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -07001261 /* The alloc_resource() result gets checked later */
1262 new_res = alloc_resource(GFP_KERNEL);
Toshi Kani825f7872013-04-29 15:08:19 -07001263
1264 p = &parent->child;
1265 write_lock(&resource_lock);
1266
1267 while ((res = *p)) {
1268 if (res->start >= end)
1269 break;
1270
1271 /* look for the next resource if it does not fit into */
1272 if (res->start > start || res->end < end) {
1273 p = &res->sibling;
1274 continue;
1275 }
1276
1277 if (!(res->flags & IORESOURCE_MEM))
1278 break;
1279
1280 if (!(res->flags & IORESOURCE_BUSY)) {
1281 p = &res->child;
1282 continue;
1283 }
1284
1285 /* found the target resource; let's adjust accordingly */
1286 if (res->start == start && res->end == end) {
1287 /* free the whole entry */
1288 *p = res->sibling;
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -07001289 free_resource(res);
Toshi Kani825f7872013-04-29 15:08:19 -07001290 ret = 0;
1291 } else if (res->start == start && res->end != end) {
1292 /* adjust the start */
1293 ret = __adjust_resource(res, end + 1,
1294 res->end - end);
1295 } else if (res->start != start && res->end == end) {
1296 /* adjust the end */
1297 ret = __adjust_resource(res, res->start,
1298 start - res->start);
1299 } else {
1300 /* split into two entries */
1301 if (!new_res) {
1302 ret = -ENOMEM;
1303 break;
1304 }
1305 new_res->name = res->name;
1306 new_res->start = end + 1;
1307 new_res->end = res->end;
1308 new_res->flags = res->flags;
Toshi Kani43ee4932016-01-26 21:57:19 +01001309 new_res->desc = res->desc;
Toshi Kani825f7872013-04-29 15:08:19 -07001310 new_res->parent = res->parent;
1311 new_res->sibling = res->sibling;
1312 new_res->child = NULL;
1313
1314 ret = __adjust_resource(res, res->start,
1315 start - res->start);
1316 if (ret)
1317 break;
1318 res->sibling = new_res;
1319 new_res = NULL;
1320 }
1321
1322 break;
1323 }
1324
1325 write_unlock(&resource_lock);
Yasuaki Ishimatsuebff7d82013-04-29 15:08:56 -07001326 free_resource(new_res);
Toshi Kani825f7872013-04-29 15:08:19 -07001327 return ret;
1328}
1329#endif /* CONFIG_MEMORY_HOTREMOVE */
1330
Linus Torvalds1da177e2005-04-16 15:20:36 -07001331/*
Tejun Heo9ac78492007-01-20 16:00:26 +09001332 * Managed region resource
1333 */
Thierry Reding8d388212014-08-01 14:15:10 +02001334static void devm_resource_release(struct device *dev, void *ptr)
1335{
1336 struct resource **r = ptr;
1337
1338 release_resource(*r);
1339}
1340
1341/**
1342 * devm_request_resource() - request and reserve an I/O or memory resource
1343 * @dev: device for which to request the resource
1344 * @root: root of the resource tree from which to request the resource
1345 * @new: descriptor of the resource to request
1346 *
1347 * This is a device-managed version of request_resource(). There is usually
1348 * no need to release resources requested by this function explicitly since
1349 * that will be taken care of when the device is unbound from its driver.
1350 * If for some reason the resource needs to be released explicitly, because
1351 * of ordering issues for example, drivers must call devm_release_resource()
1352 * rather than the regular release_resource().
1353 *
1354 * When a conflict is detected between any existing resources and the newly
1355 * requested resource, an error message will be printed.
1356 *
1357 * Returns 0 on success or a negative error code on failure.
1358 */
1359int devm_request_resource(struct device *dev, struct resource *root,
1360 struct resource *new)
1361{
1362 struct resource *conflict, **ptr;
1363
1364 ptr = devres_alloc(devm_resource_release, sizeof(*ptr), GFP_KERNEL);
1365 if (!ptr)
1366 return -ENOMEM;
1367
1368 *ptr = new;
1369
1370 conflict = request_resource_conflict(root, new);
1371 if (conflict) {
1372 dev_err(dev, "resource collision: %pR conflicts with %s %pR\n",
1373 new, conflict->name, conflict);
1374 devres_free(ptr);
1375 return -EBUSY;
1376 }
1377
1378 devres_add(dev, ptr);
1379 return 0;
1380}
1381EXPORT_SYMBOL(devm_request_resource);
1382
1383static int devm_resource_match(struct device *dev, void *res, void *data)
1384{
1385 struct resource **ptr = res;
1386
1387 return *ptr == data;
1388}
1389
1390/**
1391 * devm_release_resource() - release a previously requested resource
1392 * @dev: device for which to release the resource
1393 * @new: descriptor of the resource to release
1394 *
1395 * Releases a resource previously requested using devm_request_resource().
1396 */
1397void devm_release_resource(struct device *dev, struct resource *new)
1398{
1399 WARN_ON(devres_release(dev, devm_resource_release, devm_resource_match,
1400 new));
1401}
1402EXPORT_SYMBOL(devm_release_resource);
1403
Tejun Heo9ac78492007-01-20 16:00:26 +09001404struct region_devres {
1405 struct resource *parent;
1406 resource_size_t start;
1407 resource_size_t n;
1408};
1409
1410static void devm_region_release(struct device *dev, void *res)
1411{
1412 struct region_devres *this = res;
1413
1414 __release_region(this->parent, this->start, this->n);
1415}
1416
1417static int devm_region_match(struct device *dev, void *res, void *match_data)
1418{
1419 struct region_devres *this = res, *match = match_data;
1420
1421 return this->parent == match->parent &&
1422 this->start == match->start && this->n == match->n;
1423}
1424
1425struct resource * __devm_request_region(struct device *dev,
1426 struct resource *parent, resource_size_t start,
1427 resource_size_t n, const char *name)
1428{
1429 struct region_devres *dr = NULL;
1430 struct resource *res;
1431
1432 dr = devres_alloc(devm_region_release, sizeof(struct region_devres),
1433 GFP_KERNEL);
1434 if (!dr)
1435 return NULL;
1436
1437 dr->parent = parent;
1438 dr->start = start;
1439 dr->n = n;
1440
Arjan van de Vene8de1482008-10-22 19:55:31 -07001441 res = __request_region(parent, start, n, name, 0);
Tejun Heo9ac78492007-01-20 16:00:26 +09001442 if (res)
1443 devres_add(dev, dr);
1444 else
1445 devres_free(dr);
1446
1447 return res;
1448}
1449EXPORT_SYMBOL(__devm_request_region);
1450
1451void __devm_release_region(struct device *dev, struct resource *parent,
1452 resource_size_t start, resource_size_t n)
1453{
1454 struct region_devres match_data = { parent, start, n };
1455
1456 __release_region(parent, start, n);
1457 WARN_ON(devres_destroy(dev, devm_region_release, devm_region_match,
1458 &match_data));
1459}
1460EXPORT_SYMBOL(__devm_release_region);
1461
1462/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001463 * Called from init/main.c to reserve IO ports.
1464 */
1465#define MAXRESERVE 4
1466static int __init reserve_setup(char *str)
1467{
1468 static int reserved;
1469 static struct resource reserve[MAXRESERVE];
1470
1471 for (;;) {
Zhang Rui8bc1ad72009-06-30 11:41:31 -07001472 unsigned int io_start, io_num;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001473 int x = reserved;
1474
1475 if (get_option (&str, &io_start) != 2)
1476 break;
1477 if (get_option (&str, &io_num) == 0)
1478 break;
1479 if (x < MAXRESERVE) {
1480 struct resource *res = reserve + x;
1481 res->name = "reserved";
1482 res->start = io_start;
1483 res->end = io_start + io_num - 1;
1484 res->flags = IORESOURCE_BUSY;
Toshi Kani43ee4932016-01-26 21:57:19 +01001485 res->desc = IORES_DESC_NONE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001486 res->child = NULL;
1487 if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, res) == 0)
1488 reserved = x+1;
1489 }
1490 }
1491 return 1;
1492}
1493
1494__setup("reserve=", reserve_setup);
Suresh Siddha379daf62008-09-25 18:43:34 -07001495
1496/*
1497 * Check if the requested addr and size spans more than any slot in the
1498 * iomem resource tree.
1499 */
1500int iomem_map_sanity_check(resource_size_t addr, unsigned long size)
1501{
1502 struct resource *p = &iomem_resource;
1503 int err = 0;
1504 loff_t l;
1505
1506 read_lock(&resource_lock);
1507 for (p = p->child; p ; p = r_next(NULL, p, &l)) {
1508 /*
1509 * We can probably skip the resources without
1510 * IORESOURCE_IO attribute?
1511 */
1512 if (p->start >= addr + size)
1513 continue;
1514 if (p->end < addr)
1515 continue;
Suresh Siddhad68612b2008-10-28 11:45:42 -07001516 if (PFN_DOWN(p->start) <= PFN_DOWN(addr) &&
1517 PFN_DOWN(p->end) >= PFN_DOWN(addr + size - 1))
Suresh Siddha379daf62008-09-25 18:43:34 -07001518 continue;
Arjan van de Ven3ac52662008-12-13 09:15:27 -08001519 /*
1520 * if a resource is "BUSY", it's not a hardware resource
1521 * but a driver mapping of such a resource; we don't want
1522 * to warn for those; some drivers legitimately map only
1523 * partial hardware resources. (example: vesafb)
1524 */
1525 if (p->flags & IORESOURCE_BUSY)
1526 continue;
1527
Bjorn Helgaase4c72962014-04-14 15:38:11 -06001528 printk(KERN_WARNING "resource sanity check: requesting [mem %#010llx-%#010llx], which spans more than %s %pR\n",
Ingo Molnar13eb8372008-09-26 10:10:12 +02001529 (unsigned long long)addr,
1530 (unsigned long long)(addr + size - 1),
Bjorn Helgaase4c72962014-04-14 15:38:11 -06001531 p->name, p);
Suresh Siddha379daf62008-09-25 18:43:34 -07001532 err = -1;
1533 break;
1534 }
1535 read_unlock(&resource_lock);
1536
1537 return err;
1538}
Arjan van de Vene8de1482008-10-22 19:55:31 -07001539
1540#ifdef CONFIG_STRICT_DEVMEM
1541static int strict_iomem_checks = 1;
1542#else
1543static int strict_iomem_checks;
1544#endif
1545
1546/*
1547 * check if an address is reserved in the iomem resource tree
1548 * returns 1 if reserved, 0 if not reserved.
1549 */
1550int iomem_is_exclusive(u64 addr)
1551{
1552 struct resource *p = &iomem_resource;
1553 int err = 0;
1554 loff_t l;
1555 int size = PAGE_SIZE;
1556
1557 if (!strict_iomem_checks)
1558 return 0;
1559
1560 addr = addr & PAGE_MASK;
1561
1562 read_lock(&resource_lock);
1563 for (p = p->child; p ; p = r_next(NULL, p, &l)) {
1564 /*
1565 * We can probably skip the resources without
1566 * IORESOURCE_IO attribute?
1567 */
1568 if (p->start >= addr + size)
1569 break;
1570 if (p->end < addr)
1571 continue;
Dan Williams90a545e2015-11-23 15:49:03 -08001572 /*
1573 * A resource is exclusive if IORESOURCE_EXCLUSIVE is set
1574 * or CONFIG_IO_STRICT_DEVMEM is enabled and the
1575 * resource is busy.
1576 */
1577 if ((p->flags & IORESOURCE_BUSY) == 0)
1578 continue;
1579 if (IS_ENABLED(CONFIG_IO_STRICT_DEVMEM)
1580 || p->flags & IORESOURCE_EXCLUSIVE) {
Arjan van de Vene8de1482008-10-22 19:55:31 -07001581 err = 1;
1582 break;
1583 }
1584 }
1585 read_unlock(&resource_lock);
1586
1587 return err;
1588}
1589
Jiang Liu90e97822015-02-05 13:44:43 +08001590struct resource_entry *resource_list_create_entry(struct resource *res,
1591 size_t extra_size)
1592{
1593 struct resource_entry *entry;
1594
1595 entry = kzalloc(sizeof(*entry) + extra_size, GFP_KERNEL);
1596 if (entry) {
1597 INIT_LIST_HEAD(&entry->node);
1598 entry->res = res ? res : &entry->__res;
1599 }
1600
1601 return entry;
1602}
1603EXPORT_SYMBOL(resource_list_create_entry);
1604
1605void resource_list_free(struct list_head *head)
1606{
1607 struct resource_entry *entry, *tmp;
1608
1609 list_for_each_entry_safe(entry, tmp, head, node)
1610 resource_list_destroy_entry(entry);
1611}
1612EXPORT_SYMBOL(resource_list_free);
1613
Arjan van de Vene8de1482008-10-22 19:55:31 -07001614static int __init strict_iomem(char *str)
1615{
1616 if (strstr(str, "relaxed"))
1617 strict_iomem_checks = 0;
1618 if (strstr(str, "strict"))
1619 strict_iomem_checks = 1;
1620 return 1;
1621}
1622
1623__setup("iomem=", strict_iomem);