xref: /linux/drivers/mtd/mtdpart.c (revision 4bedea94545165364618d403d03b61d797acba0b)
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 1.51 2004/11/16 18:28:59 dwmw2 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/config.h>
20 #include <linux/kmod.h>
21 #include <linux/mtd/mtd.h>
22 #include <linux/mtd/partitions.h>
23 #include <linux/mtd/compatmac.h>
24 
25 /* Our partition linked list */
26 static LIST_HEAD(mtd_partitions);
27 
28 /* Our partition node structure */
29 struct mtd_part {
30 	struct mtd_info mtd;
31 	struct mtd_info *master;
32 	u_int32_t offset;
33 	int index;
34 	struct list_head list;
35 	int registered;
36 };
37 
38 /*
39  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
40  * the pointer to that structure with this macro.
41  */
42 #define PART(x)  ((struct mtd_part *)(x))
43 
44 
45 /*
46  * MTD methods which simply translate the effective address and pass through
47  * to the _real_ device.
48  */
49 
50 static int part_read (struct mtd_info *mtd, loff_t from, size_t len,
51 			size_t *retlen, u_char *buf)
52 {
53 	struct mtd_part *part = PART(mtd);
54 	if (from >= mtd->size)
55 		len = 0;
56 	else if (from + len > mtd->size)
57 		len = mtd->size - from;
58 	if (part->master->read_ecc == NULL)
59 		return part->master->read (part->master, from + part->offset,
60 					len, retlen, buf);
61 	else
62 		return part->master->read_ecc (part->master, from + part->offset,
63 					len, retlen, buf, NULL, &mtd->oobinfo);
64 }
65 
66 static int part_point (struct mtd_info *mtd, loff_t from, size_t len,
67 			size_t *retlen, u_char **buf)
68 {
69 	struct mtd_part *part = PART(mtd);
70 	if (from >= mtd->size)
71 		len = 0;
72 	else if (from + len > mtd->size)
73 		len = mtd->size - from;
74 	return part->master->point (part->master, from + part->offset,
75 				    len, retlen, buf);
76 }
77 static void part_unpoint (struct mtd_info *mtd, u_char *addr, loff_t from, size_t len)
78 {
79 	struct mtd_part *part = PART(mtd);
80 
81 	part->master->unpoint (part->master, addr, from + part->offset, len);
82 }
83 
84 
85 static int part_read_ecc (struct mtd_info *mtd, loff_t from, size_t len,
86 			size_t *retlen, u_char *buf, u_char *eccbuf, struct nand_oobinfo *oobsel)
87 {
88 	struct mtd_part *part = PART(mtd);
89 	if (oobsel == NULL)
90 		oobsel = &mtd->oobinfo;
91 	if (from >= mtd->size)
92 		len = 0;
93 	else if (from + len > mtd->size)
94 		len = mtd->size - from;
95 	return part->master->read_ecc (part->master, from + part->offset,
96 					len, retlen, buf, eccbuf, oobsel);
97 }
98 
99 static int part_read_oob (struct mtd_info *mtd, loff_t from, size_t len,
100 			size_t *retlen, u_char *buf)
101 {
102 	struct mtd_part *part = PART(mtd);
103 	if (from >= mtd->size)
104 		len = 0;
105 	else if (from + len > mtd->size)
106 		len = mtd->size - from;
107 	return part->master->read_oob (part->master, from + part->offset,
108 					len, retlen, buf);
109 }
110 
111 static int part_read_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
112 			size_t *retlen, u_char *buf)
113 {
114 	struct mtd_part *part = PART(mtd);
115 	return part->master->read_user_prot_reg (part->master, from,
116 					len, retlen, buf);
117 }
118 
119 static int part_read_fact_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
120 			size_t *retlen, u_char *buf)
121 {
122 	struct mtd_part *part = PART(mtd);
123 	return part->master->read_fact_prot_reg (part->master, from,
124 					len, retlen, buf);
125 }
126 
127 static int part_write (struct mtd_info *mtd, loff_t to, size_t len,
128 			size_t *retlen, const u_char *buf)
129 {
130 	struct mtd_part *part = PART(mtd);
131 	if (!(mtd->flags & MTD_WRITEABLE))
132 		return -EROFS;
133 	if (to >= mtd->size)
134 		len = 0;
135 	else if (to + len > mtd->size)
136 		len = mtd->size - to;
137 	if (part->master->write_ecc == NULL)
138 		return part->master->write (part->master, to + part->offset,
139 					len, retlen, buf);
140 	else
141 		return part->master->write_ecc (part->master, to + part->offset,
142 					len, retlen, buf, NULL, &mtd->oobinfo);
143 
144 }
145 
146 static int part_write_ecc (struct mtd_info *mtd, loff_t to, size_t len,
147 			size_t *retlen, const u_char *buf,
148 			 u_char *eccbuf, struct nand_oobinfo *oobsel)
149 {
150 	struct mtd_part *part = PART(mtd);
151 	if (!(mtd->flags & MTD_WRITEABLE))
152 		return -EROFS;
153 	if (oobsel == NULL)
154 		oobsel = &mtd->oobinfo;
155 	if (to >= mtd->size)
156 		len = 0;
157 	else if (to + len > mtd->size)
158 		len = mtd->size - to;
159 	return part->master->write_ecc (part->master, to + part->offset,
160 					len, retlen, buf, eccbuf, oobsel);
161 }
162 
163 static int part_write_oob (struct mtd_info *mtd, loff_t to, size_t len,
164 			size_t *retlen, const u_char *buf)
165 {
166 	struct mtd_part *part = PART(mtd);
167 	if (!(mtd->flags & MTD_WRITEABLE))
168 		return -EROFS;
169 	if (to >= mtd->size)
170 		len = 0;
171 	else if (to + len > mtd->size)
172 		len = mtd->size - to;
173 	return part->master->write_oob (part->master, to + part->offset,
174 					len, retlen, buf);
175 }
176 
177 static int part_write_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
178 			size_t *retlen, u_char *buf)
179 {
180 	struct mtd_part *part = PART(mtd);
181 	return part->master->write_user_prot_reg (part->master, from,
182 					len, retlen, buf);
183 }
184 
185 static int part_writev (struct mtd_info *mtd,  const struct kvec *vecs,
186 			 unsigned long count, loff_t to, size_t *retlen)
187 {
188 	struct mtd_part *part = PART(mtd);
189 	if (!(mtd->flags & MTD_WRITEABLE))
190 		return -EROFS;
191 	if (part->master->writev_ecc == NULL)
192 		return part->master->writev (part->master, vecs, count,
193 					to + part->offset, retlen);
194 	else
195 		return part->master->writev_ecc (part->master, vecs, count,
196 					to + part->offset, retlen,
197 					NULL, &mtd->oobinfo);
198 }
199 
200 static int part_readv (struct mtd_info *mtd,  struct kvec *vecs,
201 			 unsigned long count, loff_t from, size_t *retlen)
202 {
203 	struct mtd_part *part = PART(mtd);
204 	if (part->master->readv_ecc == NULL)
205 		return part->master->readv (part->master, vecs, count,
206 					from + part->offset, retlen);
207 	else
208 		return part->master->readv_ecc (part->master, vecs, count,
209 					from + part->offset, retlen,
210 					NULL, &mtd->oobinfo);
211 }
212 
213 static int part_writev_ecc (struct mtd_info *mtd,  const struct kvec *vecs,
214 			 unsigned long count, loff_t to, size_t *retlen,
215 			 u_char *eccbuf,  struct nand_oobinfo *oobsel)
216 {
217 	struct mtd_part *part = PART(mtd);
218 	if (!(mtd->flags & MTD_WRITEABLE))
219 		return -EROFS;
220 	if (oobsel == NULL)
221 		oobsel = &mtd->oobinfo;
222 	return part->master->writev_ecc (part->master, vecs, count,
223 					to + part->offset, retlen,
224 					eccbuf, oobsel);
225 }
226 
227 static int part_readv_ecc (struct mtd_info *mtd,  struct kvec *vecs,
228 			 unsigned long count, loff_t from, size_t *retlen,
229 			 u_char *eccbuf,  struct nand_oobinfo *oobsel)
230 {
231 	struct mtd_part *part = PART(mtd);
232 	if (oobsel == NULL)
233 		oobsel = &mtd->oobinfo;
234 	return part->master->readv_ecc (part->master, vecs, count,
235 					from + part->offset, retlen,
236 					eccbuf, oobsel);
237 }
238 
239 static int part_erase (struct mtd_info *mtd, struct erase_info *instr)
240 {
241 	struct mtd_part *part = PART(mtd);
242 	int ret;
243 	if (!(mtd->flags & MTD_WRITEABLE))
244 		return -EROFS;
245 	if (instr->addr >= mtd->size)
246 		return -EINVAL;
247 	instr->addr += part->offset;
248 	ret = part->master->erase(part->master, instr);
249 	return ret;
250 }
251 
252 void mtd_erase_callback(struct erase_info *instr)
253 {
254 	if (instr->mtd->erase == part_erase) {
255 		struct mtd_part *part = PART(instr->mtd);
256 
257 		if (instr->fail_addr != 0xffffffff)
258 			instr->fail_addr -= part->offset;
259 		instr->addr -= part->offset;
260 	}
261 	if (instr->callback)
262 		instr->callback(instr);
263 }
264 EXPORT_SYMBOL_GPL(mtd_erase_callback);
265 
266 static int part_lock (struct mtd_info *mtd, loff_t ofs, size_t len)
267 {
268 	struct mtd_part *part = PART(mtd);
269 	if ((len + ofs) > mtd->size)
270 		return -EINVAL;
271 	return part->master->lock(part->master, ofs + part->offset, len);
272 }
273 
274 static int part_unlock (struct mtd_info *mtd, loff_t ofs, size_t len)
275 {
276 	struct mtd_part *part = PART(mtd);
277 	if ((len + ofs) > mtd->size)
278 		return -EINVAL;
279 	return part->master->unlock(part->master, ofs + part->offset, len);
280 }
281 
282 static void part_sync(struct mtd_info *mtd)
283 {
284 	struct mtd_part *part = PART(mtd);
285 	part->master->sync(part->master);
286 }
287 
288 static int part_suspend(struct mtd_info *mtd)
289 {
290 	struct mtd_part *part = PART(mtd);
291 	return part->master->suspend(part->master);
292 }
293 
294 static void part_resume(struct mtd_info *mtd)
295 {
296 	struct mtd_part *part = PART(mtd);
297 	part->master->resume(part->master);
298 }
299 
300 static int part_block_isbad (struct mtd_info *mtd, loff_t ofs)
301 {
302 	struct mtd_part *part = PART(mtd);
303 	if (ofs >= mtd->size)
304 		return -EINVAL;
305 	ofs += part->offset;
306 	return part->master->block_isbad(part->master, ofs);
307 }
308 
309 static int part_block_markbad (struct mtd_info *mtd, loff_t ofs)
310 {
311 	struct mtd_part *part = PART(mtd);
312 	if (!(mtd->flags & MTD_WRITEABLE))
313 		return -EROFS;
314 	if (ofs >= mtd->size)
315 		return -EINVAL;
316 	ofs += part->offset;
317 	return part->master->block_markbad(part->master, ofs);
318 }
319 
320 /*
321  * This function unregisters and destroy all slave MTD objects which are
322  * attached to the given master MTD object.
323  */
324 
325 int del_mtd_partitions(struct mtd_info *master)
326 {
327 	struct list_head *node;
328 	struct mtd_part *slave;
329 
330 	for (node = mtd_partitions.next;
331 	     node != &mtd_partitions;
332 	     node = node->next) {
333 		slave = list_entry(node, struct mtd_part, list);
334 		if (slave->master == master) {
335 			struct list_head *prev = node->prev;
336 			__list_del(prev, node->next);
337 			if(slave->registered)
338 				del_mtd_device(&slave->mtd);
339 			kfree(slave);
340 			node = prev;
341 		}
342 	}
343 
344 	return 0;
345 }
346 
347 /*
348  * This function, given a master MTD object and a partition table, creates
349  * and registers slave MTD objects which are bound to the master according to
350  * the partition definitions.
351  * (Q: should we register the master MTD object as well?)
352  */
353 
354 int add_mtd_partitions(struct mtd_info *master,
355 		       const struct mtd_partition *parts,
356 		       int nbparts)
357 {
358 	struct mtd_part *slave;
359 	u_int32_t cur_offset = 0;
360 	int i;
361 
362 	printk (KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
363 
364 	for (i = 0; i < nbparts; i++) {
365 
366 		/* allocate the partition structure */
367 		slave = kmalloc (sizeof(*slave), GFP_KERNEL);
368 		if (!slave) {
369 			printk ("memory allocation error while creating partitions for \"%s\"\n",
370 				master->name);
371 			del_mtd_partitions(master);
372 			return -ENOMEM;
373 		}
374 		memset(slave, 0, sizeof(*slave));
375 		list_add(&slave->list, &mtd_partitions);
376 
377 		/* set up the MTD object for this partition */
378 		slave->mtd.type = master->type;
379 		slave->mtd.flags = master->flags & ~parts[i].mask_flags;
380 		slave->mtd.size = parts[i].size;
381 		slave->mtd.oobblock = master->oobblock;
382 		slave->mtd.oobsize = master->oobsize;
383 		slave->mtd.ecctype = master->ecctype;
384 		slave->mtd.eccsize = master->eccsize;
385 
386 		slave->mtd.name = parts[i].name;
387 		slave->mtd.bank_size = master->bank_size;
388 		slave->mtd.owner = master->owner;
389 
390 		slave->mtd.read = part_read;
391 		slave->mtd.write = part_write;
392 
393 		if(master->point && master->unpoint){
394 			slave->mtd.point = part_point;
395 			slave->mtd.unpoint = part_unpoint;
396 		}
397 
398 		if (master->read_ecc)
399 			slave->mtd.read_ecc = part_read_ecc;
400 		if (master->write_ecc)
401 			slave->mtd.write_ecc = part_write_ecc;
402 		if (master->read_oob)
403 			slave->mtd.read_oob = part_read_oob;
404 		if (master->write_oob)
405 			slave->mtd.write_oob = part_write_oob;
406 		if(master->read_user_prot_reg)
407 			slave->mtd.read_user_prot_reg = part_read_user_prot_reg;
408 		if(master->read_fact_prot_reg)
409 			slave->mtd.read_fact_prot_reg = part_read_fact_prot_reg;
410 		if(master->write_user_prot_reg)
411 			slave->mtd.write_user_prot_reg = part_write_user_prot_reg;
412 		if (master->sync)
413 			slave->mtd.sync = part_sync;
414 		if (!i && master->suspend && master->resume) {
415 				slave->mtd.suspend = part_suspend;
416 				slave->mtd.resume = part_resume;
417 		}
418 		if (master->writev)
419 			slave->mtd.writev = part_writev;
420 		if (master->readv)
421 			slave->mtd.readv = part_readv;
422 		if (master->writev_ecc)
423 			slave->mtd.writev_ecc = part_writev_ecc;
424 		if (master->readv_ecc)
425 			slave->mtd.readv_ecc = part_readv_ecc;
426 		if (master->lock)
427 			slave->mtd.lock = part_lock;
428 		if (master->unlock)
429 			slave->mtd.unlock = part_unlock;
430 		if (master->block_isbad)
431 			slave->mtd.block_isbad = part_block_isbad;
432 		if (master->block_markbad)
433 			slave->mtd.block_markbad = part_block_markbad;
434 		slave->mtd.erase = part_erase;
435 		slave->master = master;
436 		slave->offset = parts[i].offset;
437 		slave->index = i;
438 
439 		if (slave->offset == MTDPART_OFS_APPEND)
440 			slave->offset = cur_offset;
441 		if (slave->offset == MTDPART_OFS_NXTBLK) {
442 			u_int32_t emask = master->erasesize-1;
443 			slave->offset = (cur_offset + emask) & ~emask;
444 			if (slave->offset != cur_offset) {
445 				printk(KERN_NOTICE "Moving partition %d: "
446 				       "0x%08x -> 0x%08x\n", i,
447 				       cur_offset, slave->offset);
448 			}
449 		}
450 		if (slave->mtd.size == MTDPART_SIZ_FULL)
451 			slave->mtd.size = master->size - slave->offset;
452 		cur_offset = slave->offset + slave->mtd.size;
453 
454 		printk (KERN_NOTICE "0x%08x-0x%08x : \"%s\"\n", slave->offset,
455 			slave->offset + slave->mtd.size, slave->mtd.name);
456 
457 		/* let's do some sanity checks */
458 		if (slave->offset >= master->size) {
459 				/* let's register it anyway to preserve ordering */
460 			slave->offset = 0;
461 			slave->mtd.size = 0;
462 			printk ("mtd: partition \"%s\" is out of reach -- disabled\n",
463 				parts[i].name);
464 		}
465 		if (slave->offset + slave->mtd.size > master->size) {
466 			slave->mtd.size = master->size - slave->offset;
467 			printk ("mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#x\n",
468 				parts[i].name, master->name, slave->mtd.size);
469 		}
470 		if (master->numeraseregions>1) {
471 			/* Deal with variable erase size stuff */
472 			int i;
473 			struct mtd_erase_region_info *regions = master->eraseregions;
474 
475 			/* Find the first erase regions which is part of this partition. */
476 			for (i=0; i < master->numeraseregions && slave->offset >= regions[i].offset; i++)
477 				;
478 
479 			for (i--; i < master->numeraseregions && slave->offset + slave->mtd.size > regions[i].offset; i++) {
480 				if (slave->mtd.erasesize < regions[i].erasesize) {
481 					slave->mtd.erasesize = regions[i].erasesize;
482 				}
483 			}
484 		} else {
485 			/* Single erase size */
486 			slave->mtd.erasesize = master->erasesize;
487 		}
488 
489 		if ((slave->mtd.flags & MTD_WRITEABLE) &&
490 		    (slave->offset % slave->mtd.erasesize)) {
491 			/* Doesn't start on a boundary of major erase size */
492 			/* FIXME: Let it be writable if it is on a boundary of _minor_ erase size though */
493 			slave->mtd.flags &= ~MTD_WRITEABLE;
494 			printk ("mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
495 				parts[i].name);
496 		}
497 		if ((slave->mtd.flags & MTD_WRITEABLE) &&
498 		    (slave->mtd.size % slave->mtd.erasesize)) {
499 			slave->mtd.flags &= ~MTD_WRITEABLE;
500 			printk ("mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
501 				parts[i].name);
502 		}
503 
504 		/* copy oobinfo from master */
505 		memcpy(&slave->mtd.oobinfo, &master->oobinfo, sizeof(slave->mtd.oobinfo));
506 
507 		if(parts[i].mtdp)
508 		{	/* store the object pointer (caller may or may not register it */
509 			*parts[i].mtdp = &slave->mtd;
510 			slave->registered = 0;
511 		}
512 		else
513 		{
514 			/* register our partition */
515 			add_mtd_device(&slave->mtd);
516 			slave->registered = 1;
517 		}
518 	}
519 
520 	return 0;
521 }
522 
523 EXPORT_SYMBOL(add_mtd_partitions);
524 EXPORT_SYMBOL(del_mtd_partitions);
525 
526 static DEFINE_SPINLOCK(part_parser_lock);
527 static LIST_HEAD(part_parsers);
528 
529 static struct mtd_part_parser *get_partition_parser(const char *name)
530 {
531 	struct list_head *this;
532 	void *ret = NULL;
533 	spin_lock(&part_parser_lock);
534 
535 	list_for_each(this, &part_parsers) {
536 		struct mtd_part_parser *p = list_entry(this, struct mtd_part_parser, list);
537 
538 		if (!strcmp(p->name, name) && try_module_get(p->owner)) {
539 			ret = p;
540 			break;
541 		}
542 	}
543 	spin_unlock(&part_parser_lock);
544 
545 	return ret;
546 }
547 
548 int register_mtd_parser(struct mtd_part_parser *p)
549 {
550 	spin_lock(&part_parser_lock);
551 	list_add(&p->list, &part_parsers);
552 	spin_unlock(&part_parser_lock);
553 
554 	return 0;
555 }
556 
557 int deregister_mtd_parser(struct mtd_part_parser *p)
558 {
559 	spin_lock(&part_parser_lock);
560 	list_del(&p->list);
561 	spin_unlock(&part_parser_lock);
562 	return 0;
563 }
564 
565 int parse_mtd_partitions(struct mtd_info *master, const char **types,
566 			 struct mtd_partition **pparts, unsigned long origin)
567 {
568 	struct mtd_part_parser *parser;
569 	int ret = 0;
570 
571 	for ( ; ret <= 0 && *types; types++) {
572 		parser = get_partition_parser(*types);
573 #ifdef CONFIG_KMOD
574 		if (!parser && !request_module("%s", *types))
575 				parser = get_partition_parser(*types);
576 #endif
577 		if (!parser) {
578 			printk(KERN_NOTICE "%s partition parsing not available\n",
579 			       *types);
580 			continue;
581 		}
582 		ret = (*parser->parse_fn)(master, pparts, origin);
583 		if (ret > 0) {
584 			printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
585 			       ret, parser->name, master->name);
586 		}
587 		put_partition_parser(parser);
588 	}
589 	return ret;
590 }
591 
592 EXPORT_SYMBOL_GPL(parse_mtd_partitions);
593 EXPORT_SYMBOL_GPL(register_mtd_parser);
594 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
595 
596 MODULE_LICENSE("GPL");
597 MODULE_AUTHOR("Nicolas Pitre <nico@cam.org>");
598 MODULE_DESCRIPTION("Generic support for partitioning of MTD devices");
599 
600