Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | #include <linux/module.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | #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> |
| 18 | #include <linux/seq_file.h> |
Tejun Heo | 9ac7849 | 2007-01-20 16:00:26 +0900 | [diff] [blame] | 19 | #include <linux/device.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | #include <asm/io.h> |
| 21 | |
| 22 | |
| 23 | struct resource ioport_resource = { |
| 24 | .name = "PCI IO", |
Greg Kroah-Hartman | 6550e07 | 2006-06-12 17:11:31 -0700 | [diff] [blame] | 25 | .start = 0, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | .end = IO_SPACE_LIMIT, |
| 27 | .flags = IORESOURCE_IO, |
| 28 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | EXPORT_SYMBOL(ioport_resource); |
| 30 | |
| 31 | struct resource iomem_resource = { |
| 32 | .name = "PCI mem", |
Greg Kroah-Hartman | 6550e07 | 2006-06-12 17:11:31 -0700 | [diff] [blame] | 33 | .start = 0, |
| 34 | .end = -1, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | .flags = IORESOURCE_MEM, |
| 36 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | EXPORT_SYMBOL(iomem_resource); |
| 38 | |
| 39 | static DEFINE_RWLOCK(resource_lock); |
| 40 | |
| 41 | #ifdef CONFIG_PROC_FS |
| 42 | |
| 43 | enum { MAX_IORES_LEVEL = 5 }; |
| 44 | |
| 45 | static void *r_next(struct seq_file *m, void *v, loff_t *pos) |
| 46 | { |
| 47 | struct resource *p = v; |
| 48 | (*pos)++; |
| 49 | if (p->child) |
| 50 | return p->child; |
| 51 | while (!p->sibling && p->parent) |
| 52 | p = p->parent; |
| 53 | return p->sibling; |
| 54 | } |
| 55 | |
| 56 | static void *r_start(struct seq_file *m, loff_t *pos) |
| 57 | __acquires(resource_lock) |
| 58 | { |
| 59 | struct resource *p = m->private; |
| 60 | loff_t l = 0; |
| 61 | read_lock(&resource_lock); |
| 62 | for (p = p->child; p && l < *pos; p = r_next(m, p, &l)) |
| 63 | ; |
| 64 | return p; |
| 65 | } |
| 66 | |
| 67 | static void r_stop(struct seq_file *m, void *v) |
| 68 | __releases(resource_lock) |
| 69 | { |
| 70 | read_unlock(&resource_lock); |
| 71 | } |
| 72 | |
| 73 | static int r_show(struct seq_file *m, void *v) |
| 74 | { |
| 75 | struct resource *root = m->private; |
| 76 | struct resource *r = v, *p; |
| 77 | int width = root->end < 0x10000 ? 4 : 8; |
| 78 | int depth; |
| 79 | |
| 80 | for (depth = 0, p = r; depth < MAX_IORES_LEVEL; depth++, p = p->parent) |
| 81 | if (p->parent == root) |
| 82 | break; |
Greg Kroah-Hartman | 685143ac | 2006-06-12 15:18:31 -0700 | [diff] [blame] | 83 | seq_printf(m, "%*s%0*llx-%0*llx : %s\n", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | depth * 2, "", |
Greg Kroah-Hartman | 685143ac | 2006-06-12 15:18:31 -0700 | [diff] [blame] | 85 | width, (unsigned long long) r->start, |
| 86 | width, (unsigned long long) r->end, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 87 | r->name ? r->name : "<BAD>"); |
| 88 | return 0; |
| 89 | } |
| 90 | |
Helge Deller | 15ad7cd | 2006-12-06 20:40:36 -0800 | [diff] [blame] | 91 | static const struct seq_operations resource_op = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 92 | .start = r_start, |
| 93 | .next = r_next, |
| 94 | .stop = r_stop, |
| 95 | .show = r_show, |
| 96 | }; |
| 97 | |
| 98 | static int ioports_open(struct inode *inode, struct file *file) |
| 99 | { |
| 100 | int res = seq_open(file, &resource_op); |
| 101 | if (!res) { |
| 102 | struct seq_file *m = file->private_data; |
| 103 | m->private = &ioport_resource; |
| 104 | } |
| 105 | return res; |
| 106 | } |
| 107 | |
| 108 | static int iomem_open(struct inode *inode, struct file *file) |
| 109 | { |
| 110 | int res = seq_open(file, &resource_op); |
| 111 | if (!res) { |
| 112 | struct seq_file *m = file->private_data; |
| 113 | m->private = &iomem_resource; |
| 114 | } |
| 115 | return res; |
| 116 | } |
| 117 | |
Helge Deller | 15ad7cd | 2006-12-06 20:40:36 -0800 | [diff] [blame] | 118 | static const struct file_operations proc_ioports_operations = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | .open = ioports_open, |
| 120 | .read = seq_read, |
| 121 | .llseek = seq_lseek, |
| 122 | .release = seq_release, |
| 123 | }; |
| 124 | |
Helge Deller | 15ad7cd | 2006-12-06 20:40:36 -0800 | [diff] [blame] | 125 | static const struct file_operations proc_iomem_operations = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | .open = iomem_open, |
| 127 | .read = seq_read, |
| 128 | .llseek = seq_lseek, |
| 129 | .release = seq_release, |
| 130 | }; |
| 131 | |
| 132 | static int __init ioresources_init(void) |
| 133 | { |
| 134 | struct proc_dir_entry *entry; |
| 135 | |
| 136 | entry = create_proc_entry("ioports", 0, NULL); |
| 137 | if (entry) |
| 138 | entry->proc_fops = &proc_ioports_operations; |
| 139 | entry = create_proc_entry("iomem", 0, NULL); |
| 140 | if (entry) |
| 141 | entry->proc_fops = &proc_iomem_operations; |
| 142 | return 0; |
| 143 | } |
| 144 | __initcall(ioresources_init); |
| 145 | |
| 146 | #endif /* CONFIG_PROC_FS */ |
| 147 | |
| 148 | /* Return the conflict entry if you can't request it */ |
| 149 | static struct resource * __request_resource(struct resource *root, struct resource *new) |
| 150 | { |
Greg Kroah-Hartman | d75fc8b | 2006-06-12 16:09:23 -0700 | [diff] [blame] | 151 | resource_size_t start = new->start; |
| 152 | resource_size_t end = new->end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 153 | struct resource *tmp, **p; |
| 154 | |
| 155 | if (end < start) |
| 156 | return root; |
| 157 | if (start < root->start) |
| 158 | return root; |
| 159 | if (end > root->end) |
| 160 | return root; |
| 161 | p = &root->child; |
| 162 | for (;;) { |
| 163 | tmp = *p; |
| 164 | if (!tmp || tmp->start > end) { |
| 165 | new->sibling = tmp; |
| 166 | *p = new; |
| 167 | new->parent = root; |
| 168 | return NULL; |
| 169 | } |
| 170 | p = &tmp->sibling; |
| 171 | if (tmp->end < start) |
| 172 | continue; |
| 173 | return tmp; |
| 174 | } |
| 175 | } |
| 176 | |
| 177 | static int __release_resource(struct resource *old) |
| 178 | { |
| 179 | struct resource *tmp, **p; |
| 180 | |
| 181 | p = &old->parent->child; |
| 182 | for (;;) { |
| 183 | tmp = *p; |
| 184 | if (!tmp) |
| 185 | break; |
| 186 | if (tmp == old) { |
| 187 | *p = tmp->sibling; |
| 188 | old->parent = NULL; |
| 189 | return 0; |
| 190 | } |
| 191 | p = &tmp->sibling; |
| 192 | } |
| 193 | return -EINVAL; |
| 194 | } |
| 195 | |
Randy Dunlap | e1ca66d | 2006-10-03 01:13:51 -0700 | [diff] [blame] | 196 | /** |
| 197 | * request_resource - request and reserve an I/O or memory resource |
| 198 | * @root: root resource descriptor |
| 199 | * @new: resource descriptor desired by caller |
| 200 | * |
| 201 | * Returns 0 for success, negative error code on error. |
| 202 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 203 | int request_resource(struct resource *root, struct resource *new) |
| 204 | { |
| 205 | struct resource *conflict; |
| 206 | |
| 207 | write_lock(&resource_lock); |
| 208 | conflict = __request_resource(root, new); |
| 209 | write_unlock(&resource_lock); |
| 210 | return conflict ? -EBUSY : 0; |
| 211 | } |
| 212 | |
| 213 | EXPORT_SYMBOL(request_resource); |
| 214 | |
Randy Dunlap | e1ca66d | 2006-10-03 01:13:51 -0700 | [diff] [blame] | 215 | /** |
Randy Dunlap | e1ca66d | 2006-10-03 01:13:51 -0700 | [diff] [blame] | 216 | * release_resource - release a previously reserved resource |
| 217 | * @old: resource pointer |
| 218 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 219 | int release_resource(struct resource *old) |
| 220 | { |
| 221 | int retval; |
| 222 | |
| 223 | write_lock(&resource_lock); |
| 224 | retval = __release_resource(old); |
| 225 | write_unlock(&resource_lock); |
| 226 | return retval; |
| 227 | } |
| 228 | |
| 229 | EXPORT_SYMBOL(release_resource); |
| 230 | |
Badari Pulavarty | a99824f | 2008-02-05 00:10:18 -0800 | [diff] [blame] | 231 | #if defined(CONFIG_MEMORY_HOTPLUG) && !defined(CONFIG_ARCH_HAS_WALK_MEMORY) |
KAMEZAWA Hiroyuki | 2842f11 | 2006-06-27 02:53:36 -0700 | [diff] [blame] | 232 | /* |
| 233 | * Finds the lowest memory reosurce exists within [res->start.res->end) |
| 234 | * the caller must specify res->start, res->end, res->flags. |
| 235 | * If found, returns 0, res is overwritten, if not found, returns -1. |
| 236 | */ |
KAMEZAWA Hiroyuki | 75884fb | 2007-10-16 01:26:10 -0700 | [diff] [blame] | 237 | static int find_next_system_ram(struct resource *res) |
KAMEZAWA Hiroyuki | 2842f11 | 2006-06-27 02:53:36 -0700 | [diff] [blame] | 238 | { |
| 239 | resource_size_t start, end; |
| 240 | struct resource *p; |
| 241 | |
| 242 | BUG_ON(!res); |
| 243 | |
| 244 | start = res->start; |
| 245 | end = res->end; |
KAMEZAWA Hiroyuki | 58c1b5b | 2006-08-05 12:15:01 -0700 | [diff] [blame] | 246 | BUG_ON(start >= end); |
KAMEZAWA Hiroyuki | 2842f11 | 2006-06-27 02:53:36 -0700 | [diff] [blame] | 247 | |
| 248 | read_lock(&resource_lock); |
| 249 | for (p = iomem_resource.child; p ; p = p->sibling) { |
| 250 | /* system ram is just marked as IORESOURCE_MEM */ |
| 251 | if (p->flags != res->flags) |
| 252 | continue; |
| 253 | if (p->start > end) { |
| 254 | p = NULL; |
| 255 | break; |
| 256 | } |
KAMEZAWA Hiroyuki | 58c1b5b | 2006-08-05 12:15:01 -0700 | [diff] [blame] | 257 | if ((p->end >= start) && (p->start < end)) |
KAMEZAWA Hiroyuki | 2842f11 | 2006-06-27 02:53:36 -0700 | [diff] [blame] | 258 | break; |
| 259 | } |
| 260 | read_unlock(&resource_lock); |
| 261 | if (!p) |
| 262 | return -1; |
| 263 | /* copy data */ |
KAMEZAWA Hiroyuki | 0f04ab5 | 2006-08-05 12:14:59 -0700 | [diff] [blame] | 264 | if (res->start < p->start) |
| 265 | res->start = p->start; |
| 266 | if (res->end > p->end) |
| 267 | res->end = p->end; |
KAMEZAWA Hiroyuki | 2842f11 | 2006-06-27 02:53:36 -0700 | [diff] [blame] | 268 | return 0; |
| 269 | } |
KAMEZAWA Hiroyuki | 75884fb | 2007-10-16 01:26:10 -0700 | [diff] [blame] | 270 | int |
| 271 | walk_memory_resource(unsigned long start_pfn, unsigned long nr_pages, void *arg, |
| 272 | int (*func)(unsigned long, unsigned long, void *)) |
| 273 | { |
| 274 | struct resource res; |
| 275 | unsigned long pfn, len; |
| 276 | u64 orig_end; |
| 277 | int ret = -1; |
| 278 | res.start = (u64) start_pfn << PAGE_SHIFT; |
| 279 | res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1; |
Yasunori Goto | 887c3cb | 2007-11-14 16:59:20 -0800 | [diff] [blame] | 280 | res.flags = IORESOURCE_MEM | IORESOURCE_BUSY; |
KAMEZAWA Hiroyuki | 75884fb | 2007-10-16 01:26:10 -0700 | [diff] [blame] | 281 | orig_end = res.end; |
| 282 | while ((res.start < res.end) && (find_next_system_ram(&res) >= 0)) { |
| 283 | pfn = (unsigned long)(res.start >> PAGE_SHIFT); |
| 284 | len = (unsigned long)((res.end + 1 - res.start) >> PAGE_SHIFT); |
| 285 | ret = (*func)(pfn, len, arg); |
| 286 | if (ret) |
| 287 | break; |
| 288 | res.start = res.end + 1; |
| 289 | res.end = orig_end; |
| 290 | } |
| 291 | return ret; |
| 292 | } |
| 293 | |
KAMEZAWA Hiroyuki | 2842f11 | 2006-06-27 02:53:36 -0700 | [diff] [blame] | 294 | #endif |
| 295 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 296 | /* |
| 297 | * Find empty slot in the resource tree given range and alignment. |
| 298 | */ |
| 299 | static int find_resource(struct resource *root, struct resource *new, |
Greg Kroah-Hartman | d75fc8b | 2006-06-12 16:09:23 -0700 | [diff] [blame] | 300 | resource_size_t size, resource_size_t min, |
| 301 | resource_size_t max, resource_size_t align, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | void (*alignf)(void *, struct resource *, |
Greg Kroah-Hartman | d75fc8b | 2006-06-12 16:09:23 -0700 | [diff] [blame] | 303 | resource_size_t, resource_size_t), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 304 | void *alignf_data) |
| 305 | { |
| 306 | struct resource *this = root->child; |
| 307 | |
| 308 | new->start = root->start; |
| 309 | /* |
| 310 | * Skip past an allocated resource that starts at 0, since the assignment |
| 311 | * of this->start - 1 to new->end below would cause an underflow. |
| 312 | */ |
| 313 | if (this && this->start == 0) { |
| 314 | new->start = this->end + 1; |
| 315 | this = this->sibling; |
| 316 | } |
| 317 | for(;;) { |
| 318 | if (this) |
| 319 | new->end = this->start - 1; |
| 320 | else |
| 321 | new->end = root->end; |
| 322 | if (new->start < min) |
| 323 | new->start = min; |
| 324 | if (new->end > max) |
| 325 | new->end = max; |
Nick Wilson | 8c0e33c | 2005-06-25 14:59:00 -0700 | [diff] [blame] | 326 | new->start = ALIGN(new->start, align); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 327 | if (alignf) |
| 328 | alignf(alignf_data, new, size, align); |
Lennert Buytenhek | b52402c | 2005-04-16 15:25:58 -0700 | [diff] [blame] | 329 | if (new->start < new->end && new->end - new->start >= size - 1) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 330 | new->end = new->start + size - 1; |
| 331 | return 0; |
| 332 | } |
| 333 | if (!this) |
| 334 | break; |
| 335 | new->start = this->end + 1; |
| 336 | this = this->sibling; |
| 337 | } |
| 338 | return -EBUSY; |
| 339 | } |
| 340 | |
Randy Dunlap | e1ca66d | 2006-10-03 01:13:51 -0700 | [diff] [blame] | 341 | /** |
| 342 | * allocate_resource - allocate empty slot in the resource tree given range & alignment |
| 343 | * @root: root resource descriptor |
| 344 | * @new: resource descriptor desired by caller |
| 345 | * @size: requested resource region size |
| 346 | * @min: minimum size to allocate |
| 347 | * @max: maximum size to allocate |
| 348 | * @align: alignment requested, in bytes |
| 349 | * @alignf: alignment function, optional, called if not NULL |
| 350 | * @alignf_data: arbitrary data to pass to the @alignf function |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 351 | */ |
| 352 | int allocate_resource(struct resource *root, struct resource *new, |
Greg Kroah-Hartman | d75fc8b | 2006-06-12 16:09:23 -0700 | [diff] [blame] | 353 | resource_size_t size, resource_size_t min, |
| 354 | resource_size_t max, resource_size_t align, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 355 | void (*alignf)(void *, struct resource *, |
Greg Kroah-Hartman | d75fc8b | 2006-06-12 16:09:23 -0700 | [diff] [blame] | 356 | resource_size_t, resource_size_t), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 357 | void *alignf_data) |
| 358 | { |
| 359 | int err; |
| 360 | |
| 361 | write_lock(&resource_lock); |
| 362 | err = find_resource(root, new, size, min, max, align, alignf, alignf_data); |
| 363 | if (err >= 0 && __request_resource(root, new)) |
| 364 | err = -EBUSY; |
| 365 | write_unlock(&resource_lock); |
| 366 | return err; |
| 367 | } |
| 368 | |
| 369 | EXPORT_SYMBOL(allocate_resource); |
| 370 | |
| 371 | /** |
| 372 | * insert_resource - Inserts a resource in the resource tree |
| 373 | * @parent: parent of the new resource |
| 374 | * @new: new resource to insert |
| 375 | * |
| 376 | * Returns 0 on success, -EBUSY if the resource can't be inserted. |
| 377 | * |
Matthew Wilcox | d33b6fb | 2006-06-30 02:31:24 -0700 | [diff] [blame] | 378 | * This function is equivalent to request_resource when no conflict |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 379 | * happens. If a conflict happens, and the conflicting resources |
| 380 | * entirely fit within the range of the new resource, then the new |
Matthew Wilcox | d33b6fb | 2006-06-30 02:31:24 -0700 | [diff] [blame] | 381 | * resource is inserted and the conflicting resources become children of |
| 382 | * the new resource. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 383 | */ |
| 384 | int insert_resource(struct resource *parent, struct resource *new) |
| 385 | { |
| 386 | int result; |
| 387 | struct resource *first, *next; |
| 388 | |
| 389 | write_lock(&resource_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 390 | |
Matthew Wilcox | d33b6fb | 2006-06-30 02:31:24 -0700 | [diff] [blame] | 391 | for (;; parent = first) { |
| 392 | result = 0; |
| 393 | first = __request_resource(parent, new); |
| 394 | if (!first) |
| 395 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 396 | |
Matthew Wilcox | d33b6fb | 2006-06-30 02:31:24 -0700 | [diff] [blame] | 397 | result = -EBUSY; |
| 398 | if (first == parent) |
| 399 | goto out; |
| 400 | |
| 401 | if ((first->start > new->start) || (first->end < new->end)) |
| 402 | break; |
| 403 | if ((first->start == new->start) && (first->end == new->end)) |
| 404 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 405 | } |
| 406 | |
| 407 | for (next = first; ; next = next->sibling) { |
| 408 | /* Partial overlap? Bad, and unfixable */ |
| 409 | if (next->start < new->start || next->end > new->end) |
| 410 | goto out; |
| 411 | if (!next->sibling) |
| 412 | break; |
| 413 | if (next->sibling->start > new->end) |
| 414 | break; |
| 415 | } |
| 416 | |
| 417 | result = 0; |
| 418 | |
| 419 | new->parent = parent; |
| 420 | new->sibling = next->sibling; |
| 421 | new->child = first; |
| 422 | |
| 423 | next->sibling = NULL; |
| 424 | for (next = first; next; next = next->sibling) |
| 425 | next->parent = new; |
| 426 | |
| 427 | if (parent->child == first) { |
| 428 | parent->child = new; |
| 429 | } else { |
| 430 | next = parent->child; |
| 431 | while (next->sibling != first) |
| 432 | next = next->sibling; |
| 433 | next->sibling = new; |
| 434 | } |
| 435 | |
| 436 | out: |
| 437 | write_unlock(&resource_lock); |
| 438 | return result; |
| 439 | } |
| 440 | |
Randy Dunlap | e1ca66d | 2006-10-03 01:13:51 -0700 | [diff] [blame] | 441 | /** |
| 442 | * adjust_resource - modify a resource's start and size |
| 443 | * @res: resource to modify |
| 444 | * @start: new start value |
| 445 | * @size: new size |
| 446 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 447 | * Given an existing resource, change its start and size to match the |
Randy Dunlap | e1ca66d | 2006-10-03 01:13:51 -0700 | [diff] [blame] | 448 | * arguments. Returns 0 on success, -EBUSY if it can't fit. |
| 449 | * Existing children of the resource are assumed to be immutable. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 450 | */ |
Greg Kroah-Hartman | d75fc8b | 2006-06-12 16:09:23 -0700 | [diff] [blame] | 451 | int adjust_resource(struct resource *res, resource_size_t start, resource_size_t size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 452 | { |
| 453 | struct resource *tmp, *parent = res->parent; |
Greg Kroah-Hartman | d75fc8b | 2006-06-12 16:09:23 -0700 | [diff] [blame] | 454 | resource_size_t end = start + size - 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 455 | int result = -EBUSY; |
| 456 | |
| 457 | write_lock(&resource_lock); |
| 458 | |
| 459 | if ((start < parent->start) || (end > parent->end)) |
| 460 | goto out; |
| 461 | |
| 462 | for (tmp = res->child; tmp; tmp = tmp->sibling) { |
| 463 | if ((tmp->start < start) || (tmp->end > end)) |
| 464 | goto out; |
| 465 | } |
| 466 | |
| 467 | if (res->sibling && (res->sibling->start <= end)) |
| 468 | goto out; |
| 469 | |
| 470 | tmp = parent->child; |
| 471 | if (tmp != res) { |
| 472 | while (tmp->sibling != res) |
| 473 | tmp = tmp->sibling; |
| 474 | if (start <= tmp->end) |
| 475 | goto out; |
| 476 | } |
| 477 | |
| 478 | res->start = start; |
| 479 | res->end = end; |
| 480 | result = 0; |
| 481 | |
| 482 | out: |
| 483 | write_unlock(&resource_lock); |
| 484 | return result; |
| 485 | } |
| 486 | |
| 487 | EXPORT_SYMBOL(adjust_resource); |
| 488 | |
| 489 | /* |
| 490 | * This is compatibility stuff for IO resources. |
| 491 | * |
| 492 | * Note how this, unlike the above, knows about |
| 493 | * the IO flag meanings (busy etc). |
| 494 | * |
Randy Dunlap | e1ca66d | 2006-10-03 01:13:51 -0700 | [diff] [blame] | 495 | * request_region creates a new busy region. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 496 | * |
Randy Dunlap | e1ca66d | 2006-10-03 01:13:51 -0700 | [diff] [blame] | 497 | * check_region returns non-zero if the area is already busy. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 498 | * |
Randy Dunlap | e1ca66d | 2006-10-03 01:13:51 -0700 | [diff] [blame] | 499 | * release_region releases a matching busy region. |
| 500 | */ |
| 501 | |
| 502 | /** |
| 503 | * __request_region - create a new busy resource region |
| 504 | * @parent: parent resource descriptor |
| 505 | * @start: resource start address |
| 506 | * @n: resource region size |
| 507 | * @name: reserving caller's ID string |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 508 | */ |
Greg Kroah-Hartman | d75fc8b | 2006-06-12 16:09:23 -0700 | [diff] [blame] | 509 | struct resource * __request_region(struct resource *parent, |
| 510 | resource_size_t start, resource_size_t n, |
| 511 | const char *name) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 512 | { |
Pekka J Enberg | dd39271 | 2005-09-06 15:18:31 -0700 | [diff] [blame] | 513 | struct resource *res = kzalloc(sizeof(*res), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 514 | |
| 515 | if (res) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 516 | res->name = name; |
| 517 | res->start = start; |
| 518 | res->end = start + n - 1; |
| 519 | res->flags = IORESOURCE_BUSY; |
| 520 | |
| 521 | write_lock(&resource_lock); |
| 522 | |
| 523 | for (;;) { |
| 524 | struct resource *conflict; |
| 525 | |
| 526 | conflict = __request_resource(parent, res); |
| 527 | if (!conflict) |
| 528 | break; |
| 529 | if (conflict != parent) { |
| 530 | parent = conflict; |
| 531 | if (!(conflict->flags & IORESOURCE_BUSY)) |
| 532 | continue; |
| 533 | } |
| 534 | |
| 535 | /* Uhhuh, that didn't work out.. */ |
| 536 | kfree(res); |
| 537 | res = NULL; |
| 538 | break; |
| 539 | } |
| 540 | write_unlock(&resource_lock); |
| 541 | } |
| 542 | return res; |
| 543 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 544 | EXPORT_SYMBOL(__request_region); |
| 545 | |
Randy Dunlap | e1ca66d | 2006-10-03 01:13:51 -0700 | [diff] [blame] | 546 | /** |
| 547 | * __check_region - check if a resource region is busy or free |
| 548 | * @parent: parent resource descriptor |
| 549 | * @start: resource start address |
| 550 | * @n: resource region size |
| 551 | * |
| 552 | * Returns 0 if the region is free at the moment it is checked, |
| 553 | * returns %-EBUSY if the region is busy. |
| 554 | * |
| 555 | * NOTE: |
| 556 | * This function is deprecated because its use is racy. |
| 557 | * Even if it returns 0, a subsequent call to request_region() |
| 558 | * may fail because another driver etc. just allocated the region. |
| 559 | * Do NOT use it. It will be removed from the kernel. |
| 560 | */ |
Greg Kroah-Hartman | d75fc8b | 2006-06-12 16:09:23 -0700 | [diff] [blame] | 561 | int __check_region(struct resource *parent, resource_size_t start, |
| 562 | resource_size_t n) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 563 | { |
| 564 | struct resource * res; |
| 565 | |
| 566 | res = __request_region(parent, start, n, "check-region"); |
| 567 | if (!res) |
| 568 | return -EBUSY; |
| 569 | |
| 570 | release_resource(res); |
| 571 | kfree(res); |
| 572 | return 0; |
| 573 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 574 | EXPORT_SYMBOL(__check_region); |
| 575 | |
Randy Dunlap | e1ca66d | 2006-10-03 01:13:51 -0700 | [diff] [blame] | 576 | /** |
| 577 | * __release_region - release a previously reserved resource region |
| 578 | * @parent: parent resource descriptor |
| 579 | * @start: resource start address |
| 580 | * @n: resource region size |
| 581 | * |
| 582 | * The described resource region must match a currently busy region. |
| 583 | */ |
Greg Kroah-Hartman | d75fc8b | 2006-06-12 16:09:23 -0700 | [diff] [blame] | 584 | void __release_region(struct resource *parent, resource_size_t start, |
| 585 | resource_size_t n) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 586 | { |
| 587 | struct resource **p; |
Greg Kroah-Hartman | d75fc8b | 2006-06-12 16:09:23 -0700 | [diff] [blame] | 588 | resource_size_t end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 589 | |
| 590 | p = &parent->child; |
| 591 | end = start + n - 1; |
| 592 | |
| 593 | write_lock(&resource_lock); |
| 594 | |
| 595 | for (;;) { |
| 596 | struct resource *res = *p; |
| 597 | |
| 598 | if (!res) |
| 599 | break; |
| 600 | if (res->start <= start && res->end >= end) { |
| 601 | if (!(res->flags & IORESOURCE_BUSY)) { |
| 602 | p = &res->child; |
| 603 | continue; |
| 604 | } |
| 605 | if (res->start != start || res->end != end) |
| 606 | break; |
| 607 | *p = res->sibling; |
| 608 | write_unlock(&resource_lock); |
| 609 | kfree(res); |
| 610 | return; |
| 611 | } |
| 612 | p = &res->sibling; |
| 613 | } |
| 614 | |
| 615 | write_unlock(&resource_lock); |
| 616 | |
Greg Kroah-Hartman | 685143ac | 2006-06-12 15:18:31 -0700 | [diff] [blame] | 617 | printk(KERN_WARNING "Trying to free nonexistent resource " |
| 618 | "<%016llx-%016llx>\n", (unsigned long long)start, |
| 619 | (unsigned long long)end); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 620 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 621 | EXPORT_SYMBOL(__release_region); |
| 622 | |
| 623 | /* |
Tejun Heo | 9ac7849 | 2007-01-20 16:00:26 +0900 | [diff] [blame] | 624 | * Managed region resource |
| 625 | */ |
| 626 | struct region_devres { |
| 627 | struct resource *parent; |
| 628 | resource_size_t start; |
| 629 | resource_size_t n; |
| 630 | }; |
| 631 | |
| 632 | static void devm_region_release(struct device *dev, void *res) |
| 633 | { |
| 634 | struct region_devres *this = res; |
| 635 | |
| 636 | __release_region(this->parent, this->start, this->n); |
| 637 | } |
| 638 | |
| 639 | static int devm_region_match(struct device *dev, void *res, void *match_data) |
| 640 | { |
| 641 | struct region_devres *this = res, *match = match_data; |
| 642 | |
| 643 | return this->parent == match->parent && |
| 644 | this->start == match->start && this->n == match->n; |
| 645 | } |
| 646 | |
| 647 | struct resource * __devm_request_region(struct device *dev, |
| 648 | struct resource *parent, resource_size_t start, |
| 649 | resource_size_t n, const char *name) |
| 650 | { |
| 651 | struct region_devres *dr = NULL; |
| 652 | struct resource *res; |
| 653 | |
| 654 | dr = devres_alloc(devm_region_release, sizeof(struct region_devres), |
| 655 | GFP_KERNEL); |
| 656 | if (!dr) |
| 657 | return NULL; |
| 658 | |
| 659 | dr->parent = parent; |
| 660 | dr->start = start; |
| 661 | dr->n = n; |
| 662 | |
| 663 | res = __request_region(parent, start, n, name); |
| 664 | if (res) |
| 665 | devres_add(dev, dr); |
| 666 | else |
| 667 | devres_free(dr); |
| 668 | |
| 669 | return res; |
| 670 | } |
| 671 | EXPORT_SYMBOL(__devm_request_region); |
| 672 | |
| 673 | void __devm_release_region(struct device *dev, struct resource *parent, |
| 674 | resource_size_t start, resource_size_t n) |
| 675 | { |
| 676 | struct region_devres match_data = { parent, start, n }; |
| 677 | |
| 678 | __release_region(parent, start, n); |
| 679 | WARN_ON(devres_destroy(dev, devm_region_release, devm_region_match, |
| 680 | &match_data)); |
| 681 | } |
| 682 | EXPORT_SYMBOL(__devm_release_region); |
| 683 | |
| 684 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 685 | * Called from init/main.c to reserve IO ports. |
| 686 | */ |
| 687 | #define MAXRESERVE 4 |
| 688 | static int __init reserve_setup(char *str) |
| 689 | { |
| 690 | static int reserved; |
| 691 | static struct resource reserve[MAXRESERVE]; |
| 692 | |
| 693 | for (;;) { |
| 694 | int io_start, io_num; |
| 695 | int x = reserved; |
| 696 | |
| 697 | if (get_option (&str, &io_start) != 2) |
| 698 | break; |
| 699 | if (get_option (&str, &io_num) == 0) |
| 700 | break; |
| 701 | if (x < MAXRESERVE) { |
| 702 | struct resource *res = reserve + x; |
| 703 | res->name = "reserved"; |
| 704 | res->start = io_start; |
| 705 | res->end = io_start + io_num - 1; |
| 706 | res->flags = IORESOURCE_BUSY; |
| 707 | res->child = NULL; |
| 708 | if (request_resource(res->start >= 0x10000 ? &iomem_resource : &ioport_resource, res) == 0) |
| 709 | reserved = x+1; |
| 710 | } |
| 711 | } |
| 712 | return 1; |
| 713 | } |
| 714 | |
| 715 | __setup("reserve=", reserve_setup); |