[PATCH] 64bit Resource: finally enable 64bit resource sizes
[linux-3.10.git] / kernel / resource.c
1 /*
2  *      linux/kernel/resource.c
3  *
4  * Copyright (C) 1999   Linus Torvalds
5  * Copyright (C) 1999   Martin Mares <mj@ucw.cz>
6  *
7  * Arbitrary resource management.
8  */
9
10 #include <linux/config.h>
11 #include <linux/module.h>
12 #include <linux/sched.h>
13 #include <linux/errno.h>
14 #include <linux/ioport.h>
15 #include <linux/init.h>
16 #include <linux/slab.h>
17 #include <linux/spinlock.h>
18 #include <linux/fs.h>
19 #include <linux/proc_fs.h>
20 #include <linux/seq_file.h>
21 #include <asm/io.h>
22
23
24 struct resource ioport_resource = {
25         .name   = "PCI IO",
26         .start  = 0,
27         .end    = IO_SPACE_LIMIT,
28         .flags  = IORESOURCE_IO,
29 };
30 EXPORT_SYMBOL(ioport_resource);
31
32 struct resource iomem_resource = {
33         .name   = "PCI mem",
34         .start  = 0,
35         .end    = -1,
36         .flags  = IORESOURCE_MEM,
37 };
38 EXPORT_SYMBOL(iomem_resource);
39
40 static DEFINE_RWLOCK(resource_lock);
41
42 #ifdef CONFIG_PROC_FS
43
44 enum { MAX_IORES_LEVEL = 5 };
45
46 static void *r_next(struct seq_file *m, void *v, loff_t *pos)
47 {
48         struct resource *p = v;
49         (*pos)++;
50         if (p->child)
51                 return p->child;
52         while (!p->sibling && p->parent)
53                 p = p->parent;
54         return p->sibling;
55 }
56
57 static void *r_start(struct seq_file *m, loff_t *pos)
58         __acquires(resource_lock)
59 {
60         struct resource *p = m->private;
61         loff_t l = 0;
62         read_lock(&resource_lock);
63         for (p = p->child; p && l < *pos; p = r_next(m, p, &l))
64                 ;
65         return p;
66 }
67
68 static void r_stop(struct seq_file *m, void *v)
69         __releases(resource_lock)
70 {
71         read_unlock(&resource_lock);
72 }
73
74 static int r_show(struct seq_file *m, void *v)
75 {
76         struct resource *root = m->private;
77         struct resource *r = v, *p;
78         int width = root->end < 0x10000 ? 4 : 8;
79         int depth;
80
81         for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent)
82                 if (p->parent == root)
83                         break;
84         seq_printf(m, "%*s%0*llx-%0*llx : %s\n",
85                         depth * 2, "",
86                         width, (unsigned long long) r->start,
87                         width, (unsigned long long) r->end,
88                         r->name ? r->name : "<BAD>");
89         return 0;
90 }
91
92 static struct seq_operations resource_op = {
93         .start  = r_start,
94         .next   = r_next,
95         .stop   = r_stop,
96         .show   = r_show,
97 };
98
99 static int ioports_open(struct inode *inode, struct file *file)
100 {
101         int res = seq_open(file, &resource_op);
102         if (!res) {
103                 struct seq_file *m = file->private_data;
104                 m->private = &ioport_resource;
105         }
106         return res;
107 }
108
109 static int iomem_open(struct inode *inode, struct file *file)
110 {
111         int res = seq_open(file, &resource_op);
112         if (!res) {
113                 struct seq_file *m = file->private_data;
114                 m->private = &iomem_resource;
115         }
116         return res;
117 }
118
119 static struct file_operations proc_ioports_operations = {
120         .open           = ioports_open,
121         .read           = seq_read,
122         .llseek         = seq_lseek,
123         .release        = seq_release,
124 };
125
126 static struct file_operations proc_iomem_operations = {
127         .open           = iomem_open,
128         .read           = seq_read,
129         .llseek         = seq_lseek,
130         .release        = seq_release,
131 };
132
133 static int __init ioresources_init(void)
134 {
135         struct proc_dir_entry *entry;
136
137         entry = create_proc_entry("ioports", 0, NULL);
138         if (entry)
139                 entry->proc_fops = &proc_ioports_operations;
140         entry = create_proc_entry("iomem", 0, NULL);
141         if (entry)
142                 entry->proc_fops = &proc_iomem_operations;
143         return 0;
144 }
145 __initcall(ioresources_init);
146
147 #endif /* CONFIG_PROC_FS */
148
149 /* Return the conflict entry if you can't request it */
150 static struct resource * __request_resource(struct resource *root, struct resource *new)
151 {
152         resource_size_t start = new->start;
153         resource_size_t end = new->end;
154         struct resource *tmp, **p;
155
156         if (end < start)
157                 return root;
158         if (start < root->start)
159                 return root;
160         if (end > root->end)
161                 return root;
162         p = &root->child;
163         for (;;) {
164                 tmp = *p;
165                 if (!tmp || tmp->start > end) {
166                         new->sibling = tmp;
167                         *p = new;
168                         new->parent = root;
169                         return NULL;
170                 }
171                 p = &tmp->sibling;
172                 if (tmp->end < start)
173                         continue;
174                 return tmp;
175         }
176 }
177
178 static int __release_resource(struct resource *old)
179 {
180         struct resource *tmp, **p;
181
182         p = &old->parent->child;
183         for (;;) {
184                 tmp = *p;
185                 if (!tmp)
186                         break;
187                 if (tmp == old) {
188                         *p = tmp->sibling;
189                         old->parent = NULL;
190                         return 0;
191                 }
192                 p = &tmp->sibling;
193         }
194         return -EINVAL;
195 }
196
197 int request_resource(struct resource *root, struct resource *new)
198 {
199         struct resource *conflict;
200
201         write_lock(&resource_lock);
202         conflict = __request_resource(root, new);
203         write_unlock(&resource_lock);
204         return conflict ? -EBUSY : 0;
205 }
206
207 EXPORT_SYMBOL(request_resource);
208
209 struct resource *____request_resource(struct resource *root, struct resource *new)
210 {
211         struct resource *conflict;
212
213         write_lock(&resource_lock);
214         conflict = __request_resource(root, new);
215         write_unlock(&resource_lock);
216         return conflict;
217 }
218
219 EXPORT_SYMBOL(____request_resource);
220
221 int release_resource(struct resource *old)
222 {
223         int retval;
224
225         write_lock(&resource_lock);
226         retval = __release_resource(old);
227         write_unlock(&resource_lock);
228         return retval;
229 }
230
231 EXPORT_SYMBOL(release_resource);
232
233 /*
234  * Find empty slot in the resource tree given range and alignment.
235  */
236 static int find_resource(struct resource *root, struct resource *new,
237                          resource_size_t size, resource_size_t min,
238                          resource_size_t max, resource_size_t align,
239                          void (*alignf)(void *, struct resource *,
240                                         resource_size_t, resource_size_t),
241                          void *alignf_data)
242 {
243         struct resource *this = root->child;
244
245         new->start = root->start;
246         /*
247          * Skip past an allocated resource that starts at 0, since the assignment
248          * of this->start - 1 to new->end below would cause an underflow.
249          */
250         if (this && this->start == 0) {
251                 new->start = this->end + 1;
252                 this = this->sibling;
253         }
254         for(;;) {
255                 if (this)
256                         new->end = this->start - 1;
257                 else
258                         new->end = root->end;
259                 if (new->start < min)
260                         new->start = min;
261                 if (new->end > max)
262                         new->end = max;
263                 new->start = ALIGN(new->start, align);
264                 if (alignf)
265                         alignf(alignf_data, new, size, align);
266                 if (new->start < new->end && new->end - new->start >= size - 1) {
267                         new->end = new->start + size - 1;
268                         return 0;
269                 }
270                 if (!this)
271                         break;
272                 new->start = this->end + 1;
273                 this = this->sibling;
274         }
275         return -EBUSY;
276 }
277
278 /*
279  * Allocate empty slot in the resource tree given range and alignment.
280  */
281 int allocate_resource(struct resource *root, struct resource *new,
282                       resource_size_t size, resource_size_t min,
283                       resource_size_t max, resource_size_t align,
284                       void (*alignf)(void *, struct resource *,
285                                      resource_size_t, resource_size_t),
286                       void *alignf_data)
287 {
288         int err;
289
290         write_lock(&resource_lock);
291         err = find_resource(root, new, size, min, max, align, alignf, alignf_data);
292         if (err >= 0 && __request_resource(root, new))
293                 err = -EBUSY;
294         write_unlock(&resource_lock);
295         return err;
296 }
297
298 EXPORT_SYMBOL(allocate_resource);
299
300 /**
301  * insert_resource - Inserts a resource in the resource tree
302  * @parent: parent of the new resource
303  * @new: new resource to insert
304  *
305  * Returns 0 on success, -EBUSY if the resource can't be inserted.
306  *
307  * This function is equivalent of request_resource when no conflict
308  * happens. If a conflict happens, and the conflicting resources
309  * entirely fit within the range of the new resource, then the new
310  * resource is inserted and the conflicting resources become childs of
311  * the new resource.  Otherwise the new resource becomes the child of
312  * the conflicting resource
313  */
314 int insert_resource(struct resource *parent, struct resource *new)
315 {
316         int result;
317         struct resource *first, *next;
318
319         write_lock(&resource_lock);
320  begin:
321         result = 0;
322         first = __request_resource(parent, new);
323         if (!first)
324                 goto out;
325
326         result = -EBUSY;
327         if (first == parent)
328                 goto out;
329
330         /* Resource fully contained by the clashing resource? Recurse into it */
331         if (first->start <= new->start && first->end >= new->end) {
332                 parent = first;
333                 goto begin;
334         }
335
336         for (next = first; ; next = next->sibling) {
337                 /* Partial overlap? Bad, and unfixable */
338                 if (next->start < new->start || next->end > new->end)
339                         goto out;
340                 if (!next->sibling)
341                         break;
342                 if (next->sibling->start > new->end)
343                         break;
344         }
345
346         result = 0;
347
348         new->parent = parent;
349         new->sibling = next->sibling;
350         new->child = first;
351
352         next->sibling = NULL;
353         for (next = first; next; next = next->sibling)
354                 next->parent = new;
355
356         if (parent->child == first) {
357                 parent->child = new;
358         } else {
359                 next = parent->child;
360                 while (next->sibling != first)
361                         next = next->sibling;
362                 next->sibling = new;
363         }
364
365  out:
366         write_unlock(&resource_lock);
367         return result;
368 }
369
370 EXPORT_SYMBOL(insert_resource);
371
372 /*
373  * Given an existing resource, change its start and size to match the
374  * arguments.  Returns -EBUSY if it can't fit.  Existing children of
375  * the resource are assumed to be immutable.
376  */
377 int adjust_resource(struct resource *res, resource_size_t start, resource_size_t size)
378 {
379         struct resource *tmp, *parent = res->parent;
380         resource_size_t end = start + size - 1;
381         int result = -EBUSY;
382
383         write_lock(&resource_lock);
384
385         if ((start < parent->start) || (end > parent->end))
386                 goto out;
387
388         for (tmp = res->child; tmp; tmp = tmp->sibling) {
389                 if ((tmp->start < start) || (tmp->end > end))
390                         goto out;
391         }
392
393         if (res->sibling && (res->sibling->start <= end))
394                 goto out;
395
396         tmp = parent->child;
397         if (tmp != res) {
398                 while (tmp->sibling != res)
399                         tmp = tmp->sibling;
400                 if (start <= tmp->end)
401                         goto out;
402         }
403
404         res->start = start;
405         res->end = end;
406         result = 0;
407
408  out:
409         write_unlock(&resource_lock);
410         return result;
411 }
412
413 EXPORT_SYMBOL(adjust_resource);
414
415 /*
416  * This is compatibility stuff for IO resources.
417  *
418  * Note how this, unlike the above, knows about
419  * the IO flag meanings (busy etc).
420  *
421  * Request-region creates a new busy region.
422  *
423  * Check-region returns non-zero if the area is already busy
424  *
425  * Release-region releases a matching busy region.
426  */
427 struct resource * __request_region(struct resource *parent,
428                                    resource_size_t start, resource_size_t n,
429                                    const char *name)
430 {
431         struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL);
432
433         if (res) {
434                 res->name = name;
435                 res->start = start;
436                 res->end = start + n - 1;
437                 res->flags = IORESOURCE_BUSY;
438
439                 write_lock(&resource_lock);
440
441                 for (;;) {
442                         struct resource *conflict;
443
444                         conflict = __request_resource(parent, res);
445                         if (!conflict)
446                                 break;
447                         if (conflict != parent) {
448                                 parent = conflict;
449                                 if (!(conflict->flags & IORESOURCE_BUSY))
450                                         continue;
451                         }
452
453                         /* Uhhuh, that didn't work out.. */
454                         kfree(res);
455                         res = NULL;
456                         break;
457                 }
458                 write_unlock(&resource_lock);
459         }
460         return res;
461 }
462
463 EXPORT_SYMBOL(__request_region);
464
465 int __check_region(struct resource *parent, resource_size_t start,
466                         resource_size_t n)
467 {
468         struct resource * res;
469
470         res = __request_region(parent, start, n, "check-region");
471         if (!res)
472                 return -EBUSY;
473
474         release_resource(res);
475         kfree(res);
476         return 0;
477 }
478
479 EXPORT_SYMBOL(__check_region);
480
481 void __release_region(struct resource *parent, resource_size_t start,
482                         resource_size_t n)
483 {
484         struct resource **p;
485         resource_size_t end;
486
487         p = &parent->child;
488         end = start + n - 1;
489
490         write_lock(&resource_lock);
491
492         for (;;) {
493                 struct resource *res = *p;
494
495                 if (!res)
496                         break;
497                 if (res->start <= start && res->end >= end) {
498                         if (!(res->flags & IORESOURCE_BUSY)) {
499                                 p = &res->child;
500                                 continue;
501                         }
502                         if (res->start != start || res->end != end)
503                                 break;
504                         *p = res->sibling;
505                         write_unlock(&resource_lock);
506                         kfree(res);
507                         return;
508                 }
509                 p = &res->sibling;
510         }
511
512         write_unlock(&resource_lock);
513
514         printk(KERN_WARNING "Trying to free nonexistent resource "
515                 "<%016llx-%016llx>\n", (unsigned long long)start,
516                 (unsigned long long)end);
517 }
518
519 EXPORT_SYMBOL(__release_region);
520
521 /*
522  * Called from init/main.c to reserve IO ports.
523  */
524 #define MAXRESERVE 4
525 static int __init reserve_setup(char *str)
526 {
527         static int reserved;
528         static struct resource reserve[MAXRESERVE];
529
530         for (;;) {
531                 int io_start, io_num;
532                 int x = reserved;
533
534                 if (get_option (&str, &io_start) != 2)
535                         break;
536                 if (get_option (&str, &io_num)   == 0)
537                         break;
538                 if (x < MAXRESERVE) {
539                         struct resource *res = reserve + x;
540                         res->name = "reserved";
541                         res->start = io_start;
542                         res->end = io_start + io_num - 1;
543                         res->flags = IORESOURCE_BUSY;
544                         res->child = NULL;
545                         if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, res) == 0)
546                                 reserved = x+1;
547                 }
548         }
549         return 1;
550 }
551
552 __setup("reserve=", reserve_setup);