xref: /linux/drivers/mtd/mtdpart.c (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
1 /*
2  * Simple MTD partitioning layer
3  *
4  * (C) 2000 Nicolas Pitre <nico@cam.org>
5  *
6  * This code is GPL
7  *
8  * $Id: mtdpart.c,v 1.55 2005/11/07 11:14:20 gleixner Exp $
9  *
10  * 	02-21-2002	Thomas Gleixner <gleixner@autronix.de>
11  *			added support for read_oob, write_oob
12  */
13 
14 #include <linux/module.h>
15 #include <linux/types.h>
16 #include <linux/kernel.h>
17 #include <linux/slab.h>
18 #include <linux/list.h>
19 #include <linux/kmod.h>
20 #include <linux/mtd/mtd.h>
21 #include <linux/mtd/partitions.h>
22 #include <linux/mtd/compatmac.h>
23 
24 /* Our partition linked list */
25 static LIST_HEAD(mtd_partitions);
26 
27 /* Our partition node structure */
28 struct mtd_part {
29 	struct mtd_info mtd;
30 	struct mtd_info *master;
31 	u_int32_t offset;
32 	int index;
33 	struct list_head list;
34 	int registered;
35 };
36 
37 /*
38  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
39  * the pointer to that structure with this macro.
40  */
41 #define PART(x)  ((struct mtd_part *)(x))
42 
43 
44 /*
45  * MTD methods which simply translate the effective address and pass through
46  * to the _real_ device.
47  */
48 
49 static int part_read (struct mtd_info *mtd, loff_t from, size_t len,
50 			size_t *retlen, u_char *buf)
51 {
52 	struct mtd_part *part = PART(mtd);
53 	int res;
54 
55 	if (from >= mtd->size)
56 		len = 0;
57 	else if (from + len > mtd->size)
58 		len = mtd->size - from;
59 	res = part->master->read (part->master, from + part->offset,
60 				   len, retlen, buf);
61 	if (unlikely(res)) {
62 		if (res == -EUCLEAN)
63 			mtd->ecc_stats.corrected++;
64 		if (res == -EBADMSG)
65 			mtd->ecc_stats.failed++;
66 	}
67 	return res;
68 }
69 
70 static int part_point (struct mtd_info *mtd, loff_t from, size_t len,
71 			size_t *retlen, u_char **buf)
72 {
73 	struct mtd_part *part = PART(mtd);
74 	if (from >= mtd->size)
75 		len = 0;
76 	else if (from + len > mtd->size)
77 		len = mtd->size - from;
78 	return part->master->point (part->master, from + part->offset,
79 				    len, retlen, buf);
80 }
81 
82 static void part_unpoint (struct mtd_info *mtd, u_char *addr, loff_t from, size_t len)
83 {
84 	struct mtd_part *part = PART(mtd);
85 
86 	part->master->unpoint (part->master, addr, from + part->offset, len);
87 }
88 
89 static int part_read_oob(struct mtd_info *mtd, loff_t from,
90 			 struct mtd_oob_ops *ops)
91 {
92 	struct mtd_part *part = PART(mtd);
93 	int res;
94 
95 	if (from >= mtd->size)
96 		return -EINVAL;
97 	if (ops->datbuf && from + ops->len > mtd->size)
98 		return -EINVAL;
99 	res = part->master->read_oob(part->master, from + part->offset, ops);
100 
101 	if (unlikely(res)) {
102 		if (res == -EUCLEAN)
103 			mtd->ecc_stats.corrected++;
104 		if (res == -EBADMSG)
105 			mtd->ecc_stats.failed++;
106 	}
107 	return res;
108 }
109 
110 static int part_read_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
111 			size_t *retlen, u_char *buf)
112 {
113 	struct mtd_part *part = PART(mtd);
114 	return part->master->read_user_prot_reg (part->master, from,
115 					len, retlen, buf);
116 }
117 
118 static int part_get_user_prot_info (struct mtd_info *mtd,
119 				    struct otp_info *buf, size_t len)
120 {
121 	struct mtd_part *part = PART(mtd);
122 	return part->master->get_user_prot_info (part->master, buf, len);
123 }
124 
125 static int part_read_fact_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
126 			size_t *retlen, u_char *buf)
127 {
128 	struct mtd_part *part = PART(mtd);
129 	return part->master->read_fact_prot_reg (part->master, from,
130 					len, retlen, buf);
131 }
132 
133 static int part_get_fact_prot_info (struct mtd_info *mtd,
134 				    struct otp_info *buf, size_t len)
135 {
136 	struct mtd_part *part = PART(mtd);
137 	return part->master->get_fact_prot_info (part->master, buf, len);
138 }
139 
140 static int part_write (struct mtd_info *mtd, loff_t to, size_t len,
141 			size_t *retlen, const u_char *buf)
142 {
143 	struct mtd_part *part = PART(mtd);
144 	if (!(mtd->flags & MTD_WRITEABLE))
145 		return -EROFS;
146 	if (to >= mtd->size)
147 		len = 0;
148 	else if (to + len > mtd->size)
149 		len = mtd->size - to;
150 	return part->master->write (part->master, to + part->offset,
151 				    len, retlen, buf);
152 }
153 
154 static int part_write_oob(struct mtd_info *mtd, loff_t to,
155 			 struct mtd_oob_ops *ops)
156 {
157 	struct mtd_part *part = PART(mtd);
158 
159 	if (!(mtd->flags & MTD_WRITEABLE))
160 		return -EROFS;
161 
162 	if (to >= mtd->size)
163 		return -EINVAL;
164 	if (ops->datbuf && to + ops->len > mtd->size)
165 		return -EINVAL;
166 	return part->master->write_oob(part->master, to + part->offset, ops);
167 }
168 
169 static int part_write_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
170 			size_t *retlen, u_char *buf)
171 {
172 	struct mtd_part *part = PART(mtd);
173 	return part->master->write_user_prot_reg (part->master, from,
174 					len, retlen, buf);
175 }
176 
177 static int part_lock_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len)
178 {
179 	struct mtd_part *part = PART(mtd);
180 	return part->master->lock_user_prot_reg (part->master, from, len);
181 }
182 
183 static int part_writev (struct mtd_info *mtd,  const struct kvec *vecs,
184 			 unsigned long count, loff_t to, size_t *retlen)
185 {
186 	struct mtd_part *part = PART(mtd);
187 	if (!(mtd->flags & MTD_WRITEABLE))
188 		return -EROFS;
189 	return part->master->writev (part->master, vecs, count,
190 					to + part->offset, retlen);
191 }
192 
193 static int part_erase (struct mtd_info *mtd, struct erase_info *instr)
194 {
195 	struct mtd_part *part = PART(mtd);
196 	int ret;
197 	if (!(mtd->flags & MTD_WRITEABLE))
198 		return -EROFS;
199 	if (instr->addr >= mtd->size)
200 		return -EINVAL;
201 	instr->addr += part->offset;
202 	ret = part->master->erase(part->master, instr);
203 	if (ret) {
204 		if (instr->fail_addr != 0xffffffff)
205 			instr->fail_addr -= part->offset;
206 		instr->addr -= part->offset;
207 	}
208 	return ret;
209 }
210 
211 void mtd_erase_callback(struct erase_info *instr)
212 {
213 	if (instr->mtd->erase == part_erase) {
214 		struct mtd_part *part = PART(instr->mtd);
215 
216 		if (instr->fail_addr != 0xffffffff)
217 			instr->fail_addr -= part->offset;
218 		instr->addr -= part->offset;
219 	}
220 	if (instr->callback)
221 		instr->callback(instr);
222 }
223 EXPORT_SYMBOL_GPL(mtd_erase_callback);
224 
225 static int part_lock (struct mtd_info *mtd, loff_t ofs, size_t len)
226 {
227 	struct mtd_part *part = PART(mtd);
228 	if ((len + ofs) > mtd->size)
229 		return -EINVAL;
230 	return part->master->lock(part->master, ofs + part->offset, len);
231 }
232 
233 static int part_unlock (struct mtd_info *mtd, loff_t ofs, size_t len)
234 {
235 	struct mtd_part *part = PART(mtd);
236 	if ((len + ofs) > mtd->size)
237 		return -EINVAL;
238 	return part->master->unlock(part->master, ofs + part->offset, len);
239 }
240 
241 static void part_sync(struct mtd_info *mtd)
242 {
243 	struct mtd_part *part = PART(mtd);
244 	part->master->sync(part->master);
245 }
246 
247 static int part_suspend(struct mtd_info *mtd)
248 {
249 	struct mtd_part *part = PART(mtd);
250 	return part->master->suspend(part->master);
251 }
252 
253 static void part_resume(struct mtd_info *mtd)
254 {
255 	struct mtd_part *part = PART(mtd);
256 	part->master->resume(part->master);
257 }
258 
259 static int part_block_isbad (struct mtd_info *mtd, loff_t ofs)
260 {
261 	struct mtd_part *part = PART(mtd);
262 	if (ofs >= mtd->size)
263 		return -EINVAL;
264 	ofs += part->offset;
265 	return part->master->block_isbad(part->master, ofs);
266 }
267 
268 static int part_block_markbad (struct mtd_info *mtd, loff_t ofs)
269 {
270 	struct mtd_part *part = PART(mtd);
271 	int res;
272 
273 	if (!(mtd->flags & MTD_WRITEABLE))
274 		return -EROFS;
275 	if (ofs >= mtd->size)
276 		return -EINVAL;
277 	ofs += part->offset;
278 	res = part->master->block_markbad(part->master, ofs);
279 	if (!res)
280 		mtd->ecc_stats.badblocks++;
281 	return res;
282 }
283 
284 /*
285  * This function unregisters and destroy all slave MTD objects which are
286  * attached to the given master MTD object.
287  */
288 
289 int del_mtd_partitions(struct mtd_info *master)
290 {
291 	struct list_head *node;
292 	struct mtd_part *slave;
293 
294 	for (node = mtd_partitions.next;
295 	     node != &mtd_partitions;
296 	     node = node->next) {
297 		slave = list_entry(node, struct mtd_part, list);
298 		if (slave->master == master) {
299 			struct list_head *prev = node->prev;
300 			__list_del(prev, node->next);
301 			if(slave->registered)
302 				del_mtd_device(&slave->mtd);
303 			kfree(slave);
304 			node = prev;
305 		}
306 	}
307 
308 	return 0;
309 }
310 
311 /*
312  * This function, given a master MTD object and a partition table, creates
313  * and registers slave MTD objects which are bound to the master according to
314  * the partition definitions.
315  * (Q: should we register the master MTD object as well?)
316  */
317 
318 int add_mtd_partitions(struct mtd_info *master,
319 		       const struct mtd_partition *parts,
320 		       int nbparts)
321 {
322 	struct mtd_part *slave;
323 	u_int32_t cur_offset = 0;
324 	int i;
325 
326 	printk (KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
327 
328 	for (i = 0; i < nbparts; i++) {
329 
330 		/* allocate the partition structure */
331 		slave = kzalloc (sizeof(*slave), GFP_KERNEL);
332 		if (!slave) {
333 			printk ("memory allocation error while creating partitions for \"%s\"\n",
334 				master->name);
335 			del_mtd_partitions(master);
336 			return -ENOMEM;
337 		}
338 		list_add(&slave->list, &mtd_partitions);
339 
340 		/* set up the MTD object for this partition */
341 		slave->mtd.type = master->type;
342 		slave->mtd.flags = master->flags & ~parts[i].mask_flags;
343 		slave->mtd.size = parts[i].size;
344 		slave->mtd.writesize = master->writesize;
345 		slave->mtd.oobsize = master->oobsize;
346 		slave->mtd.oobavail = master->oobavail;
347 		slave->mtd.subpage_sft = master->subpage_sft;
348 
349 		slave->mtd.name = parts[i].name;
350 		slave->mtd.bank_size = master->bank_size;
351 		slave->mtd.owner = master->owner;
352 
353 		slave->mtd.read = part_read;
354 		slave->mtd.write = part_write;
355 
356 		if(master->point && master->unpoint){
357 			slave->mtd.point = part_point;
358 			slave->mtd.unpoint = part_unpoint;
359 		}
360 
361 		if (master->read_oob)
362 			slave->mtd.read_oob = part_read_oob;
363 		if (master->write_oob)
364 			slave->mtd.write_oob = part_write_oob;
365 		if(master->read_user_prot_reg)
366 			slave->mtd.read_user_prot_reg = part_read_user_prot_reg;
367 		if(master->read_fact_prot_reg)
368 			slave->mtd.read_fact_prot_reg = part_read_fact_prot_reg;
369 		if(master->write_user_prot_reg)
370 			slave->mtd.write_user_prot_reg = part_write_user_prot_reg;
371 		if(master->lock_user_prot_reg)
372 			slave->mtd.lock_user_prot_reg = part_lock_user_prot_reg;
373 		if(master->get_user_prot_info)
374 			slave->mtd.get_user_prot_info = part_get_user_prot_info;
375 		if(master->get_fact_prot_info)
376 			slave->mtd.get_fact_prot_info = part_get_fact_prot_info;
377 		if (master->sync)
378 			slave->mtd.sync = part_sync;
379 		if (!i && master->suspend && master->resume) {
380 				slave->mtd.suspend = part_suspend;
381 				slave->mtd.resume = part_resume;
382 		}
383 		if (master->writev)
384 			slave->mtd.writev = part_writev;
385 		if (master->lock)
386 			slave->mtd.lock = part_lock;
387 		if (master->unlock)
388 			slave->mtd.unlock = part_unlock;
389 		if (master->block_isbad)
390 			slave->mtd.block_isbad = part_block_isbad;
391 		if (master->block_markbad)
392 			slave->mtd.block_markbad = part_block_markbad;
393 		slave->mtd.erase = part_erase;
394 		slave->master = master;
395 		slave->offset = parts[i].offset;
396 		slave->index = i;
397 
398 		if (slave->offset == MTDPART_OFS_APPEND)
399 			slave->offset = cur_offset;
400 		if (slave->offset == MTDPART_OFS_NXTBLK) {
401 			slave->offset = cur_offset;
402 			if ((cur_offset % master->erasesize) != 0) {
403 				/* Round up to next erasesize */
404 				slave->offset = ((cur_offset / master->erasesize) + 1) * master->erasesize;
405 				printk(KERN_NOTICE "Moving partition %d: "
406 				       "0x%08x -> 0x%08x\n", i,
407 				       cur_offset, slave->offset);
408 			}
409 		}
410 		if (slave->mtd.size == MTDPART_SIZ_FULL)
411 			slave->mtd.size = master->size - slave->offset;
412 		cur_offset = slave->offset + slave->mtd.size;
413 
414 		printk (KERN_NOTICE "0x%08x-0x%08x : \"%s\"\n", slave->offset,
415 			slave->offset + slave->mtd.size, slave->mtd.name);
416 
417 		/* let's do some sanity checks */
418 		if (slave->offset >= master->size) {
419 				/* let's register it anyway to preserve ordering */
420 			slave->offset = 0;
421 			slave->mtd.size = 0;
422 			printk ("mtd: partition \"%s\" is out of reach -- disabled\n",
423 				parts[i].name);
424 		}
425 		if (slave->offset + slave->mtd.size > master->size) {
426 			slave->mtd.size = master->size - slave->offset;
427 			printk ("mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#x\n",
428 				parts[i].name, master->name, slave->mtd.size);
429 		}
430 		if (master->numeraseregions>1) {
431 			/* Deal with variable erase size stuff */
432 			int i;
433 			struct mtd_erase_region_info *regions = master->eraseregions;
434 
435 			/* Find the first erase regions which is part of this partition. */
436 			for (i=0; i < master->numeraseregions && slave->offset >= regions[i].offset; i++)
437 				;
438 
439 			for (i--; i < master->numeraseregions && slave->offset + slave->mtd.size > regions[i].offset; i++) {
440 				if (slave->mtd.erasesize < regions[i].erasesize) {
441 					slave->mtd.erasesize = regions[i].erasesize;
442 				}
443 			}
444 		} else {
445 			/* Single erase size */
446 			slave->mtd.erasesize = master->erasesize;
447 		}
448 
449 		if ((slave->mtd.flags & MTD_WRITEABLE) &&
450 		    (slave->offset % slave->mtd.erasesize)) {
451 			/* Doesn't start on a boundary of major erase size */
452 			/* FIXME: Let it be writable if it is on a boundary of _minor_ erase size though */
453 			slave->mtd.flags &= ~MTD_WRITEABLE;
454 			printk ("mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
455 				parts[i].name);
456 		}
457 		if ((slave->mtd.flags & MTD_WRITEABLE) &&
458 		    (slave->mtd.size % slave->mtd.erasesize)) {
459 			slave->mtd.flags &= ~MTD_WRITEABLE;
460 			printk ("mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
461 				parts[i].name);
462 		}
463 
464 		slave->mtd.ecclayout = master->ecclayout;
465 		if (master->block_isbad) {
466 			uint32_t offs = 0;
467 
468 			while(offs < slave->mtd.size) {
469 				if (master->block_isbad(master,
470 							offs + slave->offset))
471 					slave->mtd.ecc_stats.badblocks++;
472 				offs += slave->mtd.erasesize;
473 			}
474 		}
475 
476 		if(parts[i].mtdp)
477 		{	/* store the object pointer (caller may or may not register it */
478 			*parts[i].mtdp = &slave->mtd;
479 			slave->registered = 0;
480 		}
481 		else
482 		{
483 			/* register our partition */
484 			add_mtd_device(&slave->mtd);
485 			slave->registered = 1;
486 		}
487 	}
488 
489 	return 0;
490 }
491 
492 EXPORT_SYMBOL(add_mtd_partitions);
493 EXPORT_SYMBOL(del_mtd_partitions);
494 
495 static DEFINE_SPINLOCK(part_parser_lock);
496 static LIST_HEAD(part_parsers);
497 
498 static struct mtd_part_parser *get_partition_parser(const char *name)
499 {
500 	struct list_head *this;
501 	void *ret = NULL;
502 	spin_lock(&part_parser_lock);
503 
504 	list_for_each(this, &part_parsers) {
505 		struct mtd_part_parser *p = list_entry(this, struct mtd_part_parser, list);
506 
507 		if (!strcmp(p->name, name) && try_module_get(p->owner)) {
508 			ret = p;
509 			break;
510 		}
511 	}
512 	spin_unlock(&part_parser_lock);
513 
514 	return ret;
515 }
516 
517 int register_mtd_parser(struct mtd_part_parser *p)
518 {
519 	spin_lock(&part_parser_lock);
520 	list_add(&p->list, &part_parsers);
521 	spin_unlock(&part_parser_lock);
522 
523 	return 0;
524 }
525 
526 int deregister_mtd_parser(struct mtd_part_parser *p)
527 {
528 	spin_lock(&part_parser_lock);
529 	list_del(&p->list);
530 	spin_unlock(&part_parser_lock);
531 	return 0;
532 }
533 
534 int parse_mtd_partitions(struct mtd_info *master, const char **types,
535 			 struct mtd_partition **pparts, unsigned long origin)
536 {
537 	struct mtd_part_parser *parser;
538 	int ret = 0;
539 
540 	for ( ; ret <= 0 && *types; types++) {
541 		parser = get_partition_parser(*types);
542 #ifdef CONFIG_KMOD
543 		if (!parser && !request_module("%s", *types))
544 				parser = get_partition_parser(*types);
545 #endif
546 		if (!parser) {
547 			printk(KERN_NOTICE "%s partition parsing not available\n",
548 			       *types);
549 			continue;
550 		}
551 		ret = (*parser->parse_fn)(master, pparts, origin);
552 		if (ret > 0) {
553 			printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
554 			       ret, parser->name, master->name);
555 		}
556 		put_partition_parser(parser);
557 	}
558 	return ret;
559 }
560 
561 EXPORT_SYMBOL_GPL(parse_mtd_partitions);
562 EXPORT_SYMBOL_GPL(register_mtd_parser);
563 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
564 
565 MODULE_LICENSE("GPL");
566 MODULE_AUTHOR("Nicolas Pitre <nico@cam.org>");
567 MODULE_DESCRIPTION("Generic support for partitioning of MTD devices");
568