xref: /openbmc/linux/drivers/mtd/mtdpart.c (revision fd589a8f)
1 /*
2  * Simple MTD partitioning layer
3  *
4  * (C) 2000 Nicolas Pitre <nico@fluxnic.net>
5  *
6  * This code is GPL
7  *
8  * 	02-21-2002	Thomas Gleixner <gleixner@autronix.de>
9  *			added support for read_oob, write_oob
10  */
11 
12 #include <linux/module.h>
13 #include <linux/types.h>
14 #include <linux/kernel.h>
15 #include <linux/slab.h>
16 #include <linux/list.h>
17 #include <linux/kmod.h>
18 #include <linux/mtd/mtd.h>
19 #include <linux/mtd/partitions.h>
20 #include <linux/mtd/compatmac.h>
21 
22 /* Our partition linked list */
23 static LIST_HEAD(mtd_partitions);
24 
25 /* Our partition node structure */
26 struct mtd_part {
27 	struct mtd_info mtd;
28 	struct mtd_info *master;
29 	uint64_t offset;
30 	struct list_head list;
31 };
32 
33 /*
34  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
35  * the pointer to that structure with this macro.
36  */
37 #define PART(x)  ((struct mtd_part *)(x))
38 
39 
40 /*
41  * MTD methods which simply translate the effective address and pass through
42  * to the _real_ device.
43  */
44 
45 static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
46 		size_t *retlen, u_char *buf)
47 {
48 	struct mtd_part *part = PART(mtd);
49 	struct mtd_ecc_stats stats;
50 	int res;
51 
52 	stats = part->master->ecc_stats;
53 
54 	if (from >= mtd->size)
55 		len = 0;
56 	else if (from + len > mtd->size)
57 		len = mtd->size - from;
58 	res = part->master->read(part->master, from + part->offset,
59 				   len, retlen, buf);
60 	if (unlikely(res)) {
61 		if (res == -EUCLEAN)
62 			mtd->ecc_stats.corrected += part->master->ecc_stats.corrected - stats.corrected;
63 		if (res == -EBADMSG)
64 			mtd->ecc_stats.failed += part->master->ecc_stats.failed - stats.failed;
65 	}
66 	return res;
67 }
68 
69 static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
70 		size_t *retlen, void **virt, resource_size_t *phys)
71 {
72 	struct mtd_part *part = PART(mtd);
73 	if (from >= mtd->size)
74 		len = 0;
75 	else if (from + len > mtd->size)
76 		len = mtd->size - from;
77 	return part->master->point (part->master, from + part->offset,
78 				    len, retlen, virt, phys);
79 }
80 
81 static void part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
82 {
83 	struct mtd_part *part = PART(mtd);
84 
85 	part->master->unpoint(part->master, from + part->offset, len);
86 }
87 
88 static unsigned long part_get_unmapped_area(struct mtd_info *mtd,
89 					    unsigned long len,
90 					    unsigned long offset,
91 					    unsigned long flags)
92 {
93 	struct mtd_part *part = PART(mtd);
94 
95 	offset += part->offset;
96 	return part->master->get_unmapped_area(part->master, len, offset,
97 					       flags);
98 }
99 
100 static int part_read_oob(struct mtd_info *mtd, loff_t from,
101 		struct mtd_oob_ops *ops)
102 {
103 	struct mtd_part *part = PART(mtd);
104 	int res;
105 
106 	if (from >= mtd->size)
107 		return -EINVAL;
108 	if (ops->datbuf && from + ops->len > mtd->size)
109 		return -EINVAL;
110 	res = part->master->read_oob(part->master, from + part->offset, ops);
111 
112 	if (unlikely(res)) {
113 		if (res == -EUCLEAN)
114 			mtd->ecc_stats.corrected++;
115 		if (res == -EBADMSG)
116 			mtd->ecc_stats.failed++;
117 	}
118 	return res;
119 }
120 
121 static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
122 		size_t len, size_t *retlen, u_char *buf)
123 {
124 	struct mtd_part *part = PART(mtd);
125 	return part->master->read_user_prot_reg(part->master, from,
126 					len, retlen, buf);
127 }
128 
129 static int part_get_user_prot_info(struct mtd_info *mtd,
130 		struct otp_info *buf, size_t len)
131 {
132 	struct mtd_part *part = PART(mtd);
133 	return part->master->get_user_prot_info(part->master, buf, len);
134 }
135 
136 static int part_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
137 		size_t len, size_t *retlen, u_char *buf)
138 {
139 	struct mtd_part *part = PART(mtd);
140 	return part->master->read_fact_prot_reg(part->master, from,
141 					len, retlen, buf);
142 }
143 
144 static int part_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
145 		size_t len)
146 {
147 	struct mtd_part *part = PART(mtd);
148 	return part->master->get_fact_prot_info(part->master, buf, len);
149 }
150 
151 static int part_write(struct mtd_info *mtd, loff_t to, size_t len,
152 		size_t *retlen, const u_char *buf)
153 {
154 	struct mtd_part *part = PART(mtd);
155 	if (!(mtd->flags & MTD_WRITEABLE))
156 		return -EROFS;
157 	if (to >= mtd->size)
158 		len = 0;
159 	else if (to + len > mtd->size)
160 		len = mtd->size - to;
161 	return part->master->write(part->master, to + part->offset,
162 				    len, retlen, buf);
163 }
164 
165 static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
166 		size_t *retlen, const u_char *buf)
167 {
168 	struct mtd_part *part = PART(mtd);
169 	if (!(mtd->flags & MTD_WRITEABLE))
170 		return -EROFS;
171 	if (to >= mtd->size)
172 		len = 0;
173 	else if (to + len > mtd->size)
174 		len = mtd->size - to;
175 	return part->master->panic_write(part->master, to + part->offset,
176 				    len, retlen, buf);
177 }
178 
179 static int part_write_oob(struct mtd_info *mtd, loff_t to,
180 		struct mtd_oob_ops *ops)
181 {
182 	struct mtd_part *part = PART(mtd);
183 
184 	if (!(mtd->flags & MTD_WRITEABLE))
185 		return -EROFS;
186 
187 	if (to >= mtd->size)
188 		return -EINVAL;
189 	if (ops->datbuf && to + ops->len > mtd->size)
190 		return -EINVAL;
191 	return part->master->write_oob(part->master, to + part->offset, ops);
192 }
193 
194 static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
195 		size_t len, size_t *retlen, u_char *buf)
196 {
197 	struct mtd_part *part = PART(mtd);
198 	return part->master->write_user_prot_reg(part->master, from,
199 					len, retlen, buf);
200 }
201 
202 static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
203 		size_t len)
204 {
205 	struct mtd_part *part = PART(mtd);
206 	return part->master->lock_user_prot_reg(part->master, from, len);
207 }
208 
209 static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,
210 		unsigned long count, loff_t to, size_t *retlen)
211 {
212 	struct mtd_part *part = PART(mtd);
213 	if (!(mtd->flags & MTD_WRITEABLE))
214 		return -EROFS;
215 	return part->master->writev(part->master, vecs, count,
216 					to + part->offset, retlen);
217 }
218 
219 static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
220 {
221 	struct mtd_part *part = PART(mtd);
222 	int ret;
223 	if (!(mtd->flags & MTD_WRITEABLE))
224 		return -EROFS;
225 	if (instr->addr >= mtd->size)
226 		return -EINVAL;
227 	instr->addr += part->offset;
228 	ret = part->master->erase(part->master, instr);
229 	if (ret) {
230 		if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
231 			instr->fail_addr -= part->offset;
232 		instr->addr -= part->offset;
233 	}
234 	return ret;
235 }
236 
237 void mtd_erase_callback(struct erase_info *instr)
238 {
239 	if (instr->mtd->erase == part_erase) {
240 		struct mtd_part *part = PART(instr->mtd);
241 
242 		if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
243 			instr->fail_addr -= part->offset;
244 		instr->addr -= part->offset;
245 	}
246 	if (instr->callback)
247 		instr->callback(instr);
248 }
249 EXPORT_SYMBOL_GPL(mtd_erase_callback);
250 
251 static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
252 {
253 	struct mtd_part *part = PART(mtd);
254 	if ((len + ofs) > mtd->size)
255 		return -EINVAL;
256 	return part->master->lock(part->master, ofs + part->offset, len);
257 }
258 
259 static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
260 {
261 	struct mtd_part *part = PART(mtd);
262 	if ((len + ofs) > mtd->size)
263 		return -EINVAL;
264 	return part->master->unlock(part->master, ofs + part->offset, len);
265 }
266 
267 static void part_sync(struct mtd_info *mtd)
268 {
269 	struct mtd_part *part = PART(mtd);
270 	part->master->sync(part->master);
271 }
272 
273 static int part_suspend(struct mtd_info *mtd)
274 {
275 	struct mtd_part *part = PART(mtd);
276 	return part->master->suspend(part->master);
277 }
278 
279 static void part_resume(struct mtd_info *mtd)
280 {
281 	struct mtd_part *part = PART(mtd);
282 	part->master->resume(part->master);
283 }
284 
285 static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
286 {
287 	struct mtd_part *part = PART(mtd);
288 	if (ofs >= mtd->size)
289 		return -EINVAL;
290 	ofs += part->offset;
291 	return part->master->block_isbad(part->master, ofs);
292 }
293 
294 static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
295 {
296 	struct mtd_part *part = PART(mtd);
297 	int res;
298 
299 	if (!(mtd->flags & MTD_WRITEABLE))
300 		return -EROFS;
301 	if (ofs >= mtd->size)
302 		return -EINVAL;
303 	ofs += part->offset;
304 	res = part->master->block_markbad(part->master, ofs);
305 	if (!res)
306 		mtd->ecc_stats.badblocks++;
307 	return res;
308 }
309 
310 /*
311  * This function unregisters and destroy all slave MTD objects which are
312  * attached to the given master MTD object.
313  */
314 
315 int del_mtd_partitions(struct mtd_info *master)
316 {
317 	struct mtd_part *slave, *next;
318 
319 	list_for_each_entry_safe(slave, next, &mtd_partitions, list)
320 		if (slave->master == master) {
321 			list_del(&slave->list);
322 			del_mtd_device(&slave->mtd);
323 			kfree(slave);
324 		}
325 
326 	return 0;
327 }
328 EXPORT_SYMBOL(del_mtd_partitions);
329 
330 static struct mtd_part *add_one_partition(struct mtd_info *master,
331 		const struct mtd_partition *part, int partno,
332 		uint64_t cur_offset)
333 {
334 	struct mtd_part *slave;
335 
336 	/* allocate the partition structure */
337 	slave = kzalloc(sizeof(*slave), GFP_KERNEL);
338 	if (!slave) {
339 		printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
340 			master->name);
341 		del_mtd_partitions(master);
342 		return NULL;
343 	}
344 	list_add(&slave->list, &mtd_partitions);
345 
346 	/* set up the MTD object for this partition */
347 	slave->mtd.type = master->type;
348 	slave->mtd.flags = master->flags & ~part->mask_flags;
349 	slave->mtd.size = part->size;
350 	slave->mtd.writesize = master->writesize;
351 	slave->mtd.oobsize = master->oobsize;
352 	slave->mtd.oobavail = master->oobavail;
353 	slave->mtd.subpage_sft = master->subpage_sft;
354 
355 	slave->mtd.name = part->name;
356 	slave->mtd.owner = master->owner;
357 	slave->mtd.backing_dev_info = master->backing_dev_info;
358 
359 	/* NOTE:  we don't arrange MTDs as a tree; it'd be error-prone
360 	 * to have the same data be in two different partitions.
361 	 */
362 	slave->mtd.dev.parent = master->dev.parent;
363 
364 	slave->mtd.read = part_read;
365 	slave->mtd.write = part_write;
366 
367 	if (master->panic_write)
368 		slave->mtd.panic_write = part_panic_write;
369 
370 	if (master->point && master->unpoint) {
371 		slave->mtd.point = part_point;
372 		slave->mtd.unpoint = part_unpoint;
373 	}
374 
375 	if (master->get_unmapped_area)
376 		slave->mtd.get_unmapped_area = part_get_unmapped_area;
377 	if (master->read_oob)
378 		slave->mtd.read_oob = part_read_oob;
379 	if (master->write_oob)
380 		slave->mtd.write_oob = part_write_oob;
381 	if (master->read_user_prot_reg)
382 		slave->mtd.read_user_prot_reg = part_read_user_prot_reg;
383 	if (master->read_fact_prot_reg)
384 		slave->mtd.read_fact_prot_reg = part_read_fact_prot_reg;
385 	if (master->write_user_prot_reg)
386 		slave->mtd.write_user_prot_reg = part_write_user_prot_reg;
387 	if (master->lock_user_prot_reg)
388 		slave->mtd.lock_user_prot_reg = part_lock_user_prot_reg;
389 	if (master->get_user_prot_info)
390 		slave->mtd.get_user_prot_info = part_get_user_prot_info;
391 	if (master->get_fact_prot_info)
392 		slave->mtd.get_fact_prot_info = part_get_fact_prot_info;
393 	if (master->sync)
394 		slave->mtd.sync = part_sync;
395 	if (!partno && !master->dev.class && master->suspend && master->resume) {
396 			slave->mtd.suspend = part_suspend;
397 			slave->mtd.resume = part_resume;
398 	}
399 	if (master->writev)
400 		slave->mtd.writev = part_writev;
401 	if (master->lock)
402 		slave->mtd.lock = part_lock;
403 	if (master->unlock)
404 		slave->mtd.unlock = part_unlock;
405 	if (master->block_isbad)
406 		slave->mtd.block_isbad = part_block_isbad;
407 	if (master->block_markbad)
408 		slave->mtd.block_markbad = part_block_markbad;
409 	slave->mtd.erase = part_erase;
410 	slave->master = master;
411 	slave->offset = part->offset;
412 
413 	if (slave->offset == MTDPART_OFS_APPEND)
414 		slave->offset = cur_offset;
415 	if (slave->offset == MTDPART_OFS_NXTBLK) {
416 		slave->offset = cur_offset;
417 		if (mtd_mod_by_eb(cur_offset, master) != 0) {
418 			/* Round up to next erasesize */
419 			slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
420 			printk(KERN_NOTICE "Moving partition %d: "
421 			       "0x%012llx -> 0x%012llx\n", partno,
422 			       (unsigned long long)cur_offset, (unsigned long long)slave->offset);
423 		}
424 	}
425 	if (slave->mtd.size == MTDPART_SIZ_FULL)
426 		slave->mtd.size = master->size - slave->offset;
427 
428 	printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
429 		(unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
430 
431 	/* let's do some sanity checks */
432 	if (slave->offset >= master->size) {
433 		/* let's register it anyway to preserve ordering */
434 		slave->offset = 0;
435 		slave->mtd.size = 0;
436 		printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
437 			part->name);
438 		goto out_register;
439 	}
440 	if (slave->offset + slave->mtd.size > master->size) {
441 		slave->mtd.size = master->size - slave->offset;
442 		printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
443 			part->name, master->name, (unsigned long long)slave->mtd.size);
444 	}
445 	if (master->numeraseregions > 1) {
446 		/* Deal with variable erase size stuff */
447 		int i, max = master->numeraseregions;
448 		u64 end = slave->offset + slave->mtd.size;
449 		struct mtd_erase_region_info *regions = master->eraseregions;
450 
451 		/* Find the first erase regions which is part of this
452 		 * partition. */
453 		for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
454 			;
455 		/* The loop searched for the region _behind_ the first one */
456 		i--;
457 
458 		/* Pick biggest erasesize */
459 		for (; i < max && regions[i].offset < end; i++) {
460 			if (slave->mtd.erasesize < regions[i].erasesize) {
461 				slave->mtd.erasesize = regions[i].erasesize;
462 			}
463 		}
464 		BUG_ON(slave->mtd.erasesize == 0);
465 	} else {
466 		/* Single erase size */
467 		slave->mtd.erasesize = master->erasesize;
468 	}
469 
470 	if ((slave->mtd.flags & MTD_WRITEABLE) &&
471 	    mtd_mod_by_eb(slave->offset, &slave->mtd)) {
472 		/* Doesn't start on a boundary of major erase size */
473 		/* FIXME: Let it be writable if it is on a boundary of
474 		 * _minor_ erase size though */
475 		slave->mtd.flags &= ~MTD_WRITEABLE;
476 		printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
477 			part->name);
478 	}
479 	if ((slave->mtd.flags & MTD_WRITEABLE) &&
480 	    mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) {
481 		slave->mtd.flags &= ~MTD_WRITEABLE;
482 		printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
483 			part->name);
484 	}
485 
486 	slave->mtd.ecclayout = master->ecclayout;
487 	if (master->block_isbad) {
488 		uint64_t offs = 0;
489 
490 		while (offs < slave->mtd.size) {
491 			if (master->block_isbad(master,
492 						offs + slave->offset))
493 				slave->mtd.ecc_stats.badblocks++;
494 			offs += slave->mtd.erasesize;
495 		}
496 	}
497 
498 out_register:
499 	/* register our partition */
500 	add_mtd_device(&slave->mtd);
501 
502 	return slave;
503 }
504 
505 /*
506  * This function, given a master MTD object and a partition table, creates
507  * and registers slave MTD objects which are bound to the master according to
508  * the partition definitions.
509  *
510  * We don't register the master, or expect the caller to have done so,
511  * for reasons of data integrity.
512  */
513 
514 int add_mtd_partitions(struct mtd_info *master,
515 		       const struct mtd_partition *parts,
516 		       int nbparts)
517 {
518 	struct mtd_part *slave;
519 	uint64_t cur_offset = 0;
520 	int i;
521 
522 	printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
523 
524 	for (i = 0; i < nbparts; i++) {
525 		slave = add_one_partition(master, parts + i, i, cur_offset);
526 		if (!slave)
527 			return -ENOMEM;
528 		cur_offset = slave->offset + slave->mtd.size;
529 	}
530 
531 	return 0;
532 }
533 EXPORT_SYMBOL(add_mtd_partitions);
534 
535 static DEFINE_SPINLOCK(part_parser_lock);
536 static LIST_HEAD(part_parsers);
537 
538 static struct mtd_part_parser *get_partition_parser(const char *name)
539 {
540 	struct mtd_part_parser *p, *ret = NULL;
541 
542 	spin_lock(&part_parser_lock);
543 
544 	list_for_each_entry(p, &part_parsers, list)
545 		if (!strcmp(p->name, name) && try_module_get(p->owner)) {
546 			ret = p;
547 			break;
548 		}
549 
550 	spin_unlock(&part_parser_lock);
551 
552 	return ret;
553 }
554 
555 int register_mtd_parser(struct mtd_part_parser *p)
556 {
557 	spin_lock(&part_parser_lock);
558 	list_add(&p->list, &part_parsers);
559 	spin_unlock(&part_parser_lock);
560 
561 	return 0;
562 }
563 EXPORT_SYMBOL_GPL(register_mtd_parser);
564 
565 int deregister_mtd_parser(struct mtd_part_parser *p)
566 {
567 	spin_lock(&part_parser_lock);
568 	list_del(&p->list);
569 	spin_unlock(&part_parser_lock);
570 	return 0;
571 }
572 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
573 
574 int parse_mtd_partitions(struct mtd_info *master, const char **types,
575 			 struct mtd_partition **pparts, unsigned long origin)
576 {
577 	struct mtd_part_parser *parser;
578 	int ret = 0;
579 
580 	for ( ; ret <= 0 && *types; types++) {
581 		parser = get_partition_parser(*types);
582 		if (!parser && !request_module("%s", *types))
583 				parser = get_partition_parser(*types);
584 		if (!parser) {
585 			printk(KERN_NOTICE "%s partition parsing not available\n",
586 			       *types);
587 			continue;
588 		}
589 		ret = (*parser->parse_fn)(master, pparts, origin);
590 		if (ret > 0) {
591 			printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
592 			       ret, parser->name, master->name);
593 		}
594 		put_partition_parser(parser);
595 	}
596 	return ret;
597 }
598 EXPORT_SYMBOL_GPL(parse_mtd_partitions);
599