xref: /openbmc/linux/drivers/mtd/mtdpart.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
1 /*
2  * Simple MTD partitioning layer
3  *
4  * Copyright © 2000 Nicolas Pitre <nico@fluxnic.net>
5  * Copyright © 2002 Thomas Gleixner <gleixner@linutronix.de>
6  * Copyright © 2000-2010 David Woodhouse <dwmw2@infradead.org>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
21  *
22  */
23 
24 #include <linux/module.h>
25 #include <linux/types.h>
26 #include <linux/kernel.h>
27 #include <linux/slab.h>
28 #include <linux/list.h>
29 #include <linux/kmod.h>
30 #include <linux/mtd/mtd.h>
31 #include <linux/mtd/partitions.h>
32 #include <linux/err.h>
33 
34 /* Our partition linked list */
35 static LIST_HEAD(mtd_partitions);
36 static DEFINE_MUTEX(mtd_partitions_mutex);
37 
38 /* Our partition node structure */
39 struct mtd_part {
40 	struct mtd_info mtd;
41 	struct mtd_info *master;
42 	uint64_t offset;
43 	struct list_head list;
44 };
45 
46 /*
47  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
48  * the pointer to that structure with this macro.
49  */
50 #define PART(x)  ((struct mtd_part *)(x))
51 
52 
53 /*
54  * MTD methods which simply translate the effective address and pass through
55  * to the _real_ device.
56  */
57 
58 static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
59 		size_t *retlen, u_char *buf)
60 {
61 	struct mtd_part *part = PART(mtd);
62 	struct mtd_ecc_stats stats;
63 	int res;
64 
65 	stats = part->master->ecc_stats;
66 
67 	if (from >= mtd->size)
68 		len = 0;
69 	else if (from + len > mtd->size)
70 		len = mtd->size - from;
71 	res = part->master->read(part->master, from + part->offset,
72 				   len, retlen, buf);
73 	if (unlikely(res)) {
74 		if (res == -EUCLEAN)
75 			mtd->ecc_stats.corrected += part->master->ecc_stats.corrected - stats.corrected;
76 		if (res == -EBADMSG)
77 			mtd->ecc_stats.failed += part->master->ecc_stats.failed - stats.failed;
78 	}
79 	return res;
80 }
81 
82 static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
83 		size_t *retlen, void **virt, resource_size_t *phys)
84 {
85 	struct mtd_part *part = PART(mtd);
86 	if (from >= mtd->size)
87 		len = 0;
88 	else if (from + len > mtd->size)
89 		len = mtd->size - from;
90 	return part->master->point (part->master, from + part->offset,
91 				    len, retlen, virt, phys);
92 }
93 
94 static void part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
95 {
96 	struct mtd_part *part = PART(mtd);
97 
98 	part->master->unpoint(part->master, from + part->offset, len);
99 }
100 
101 static unsigned long part_get_unmapped_area(struct mtd_info *mtd,
102 					    unsigned long len,
103 					    unsigned long offset,
104 					    unsigned long flags)
105 {
106 	struct mtd_part *part = PART(mtd);
107 
108 	offset += part->offset;
109 	return part->master->get_unmapped_area(part->master, len, offset,
110 					       flags);
111 }
112 
113 static int part_read_oob(struct mtd_info *mtd, loff_t from,
114 		struct mtd_oob_ops *ops)
115 {
116 	struct mtd_part *part = PART(mtd);
117 	int res;
118 
119 	if (from >= mtd->size)
120 		return -EINVAL;
121 	if (ops->datbuf && from + ops->len > mtd->size)
122 		return -EINVAL;
123 	res = part->master->read_oob(part->master, from + part->offset, ops);
124 
125 	if (unlikely(res)) {
126 		if (res == -EUCLEAN)
127 			mtd->ecc_stats.corrected++;
128 		if (res == -EBADMSG)
129 			mtd->ecc_stats.failed++;
130 	}
131 	return res;
132 }
133 
134 static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
135 		size_t len, size_t *retlen, u_char *buf)
136 {
137 	struct mtd_part *part = PART(mtd);
138 	return part->master->read_user_prot_reg(part->master, from,
139 					len, retlen, buf);
140 }
141 
142 static int part_get_user_prot_info(struct mtd_info *mtd,
143 		struct otp_info *buf, size_t len)
144 {
145 	struct mtd_part *part = PART(mtd);
146 	return part->master->get_user_prot_info(part->master, buf, len);
147 }
148 
149 static int part_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
150 		size_t len, size_t *retlen, u_char *buf)
151 {
152 	struct mtd_part *part = PART(mtd);
153 	return part->master->read_fact_prot_reg(part->master, from,
154 					len, retlen, buf);
155 }
156 
157 static int part_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
158 		size_t len)
159 {
160 	struct mtd_part *part = PART(mtd);
161 	return part->master->get_fact_prot_info(part->master, buf, len);
162 }
163 
164 static int part_write(struct mtd_info *mtd, loff_t to, size_t len,
165 		size_t *retlen, const u_char *buf)
166 {
167 	struct mtd_part *part = PART(mtd);
168 	if (!(mtd->flags & MTD_WRITEABLE))
169 		return -EROFS;
170 	if (to >= mtd->size)
171 		len = 0;
172 	else if (to + len > mtd->size)
173 		len = mtd->size - to;
174 	return part->master->write(part->master, to + part->offset,
175 				    len, retlen, buf);
176 }
177 
178 static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
179 		size_t *retlen, const u_char *buf)
180 {
181 	struct mtd_part *part = PART(mtd);
182 	if (!(mtd->flags & MTD_WRITEABLE))
183 		return -EROFS;
184 	if (to >= mtd->size)
185 		len = 0;
186 	else if (to + len > mtd->size)
187 		len = mtd->size - to;
188 	return part->master->panic_write(part->master, to + part->offset,
189 				    len, retlen, buf);
190 }
191 
192 static int part_write_oob(struct mtd_info *mtd, loff_t to,
193 		struct mtd_oob_ops *ops)
194 {
195 	struct mtd_part *part = PART(mtd);
196 
197 	if (!(mtd->flags & MTD_WRITEABLE))
198 		return -EROFS;
199 
200 	if (to >= mtd->size)
201 		return -EINVAL;
202 	if (ops->datbuf && to + ops->len > mtd->size)
203 		return -EINVAL;
204 	return part->master->write_oob(part->master, to + part->offset, ops);
205 }
206 
207 static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
208 		size_t len, size_t *retlen, u_char *buf)
209 {
210 	struct mtd_part *part = PART(mtd);
211 	return part->master->write_user_prot_reg(part->master, from,
212 					len, retlen, buf);
213 }
214 
215 static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
216 		size_t len)
217 {
218 	struct mtd_part *part = PART(mtd);
219 	return part->master->lock_user_prot_reg(part->master, from, len);
220 }
221 
222 static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,
223 		unsigned long count, loff_t to, size_t *retlen)
224 {
225 	struct mtd_part *part = PART(mtd);
226 	if (!(mtd->flags & MTD_WRITEABLE))
227 		return -EROFS;
228 	return part->master->writev(part->master, vecs, count,
229 					to + part->offset, retlen);
230 }
231 
232 static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
233 {
234 	struct mtd_part *part = PART(mtd);
235 	int ret;
236 	if (!(mtd->flags & MTD_WRITEABLE))
237 		return -EROFS;
238 	if (instr->addr >= mtd->size)
239 		return -EINVAL;
240 	instr->addr += part->offset;
241 	ret = part->master->erase(part->master, instr);
242 	if (ret) {
243 		if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
244 			instr->fail_addr -= part->offset;
245 		instr->addr -= part->offset;
246 	}
247 	return ret;
248 }
249 
250 void mtd_erase_callback(struct erase_info *instr)
251 {
252 	if (instr->mtd->erase == part_erase) {
253 		struct mtd_part *part = PART(instr->mtd);
254 
255 		if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
256 			instr->fail_addr -= part->offset;
257 		instr->addr -= part->offset;
258 	}
259 	if (instr->callback)
260 		instr->callback(instr);
261 }
262 EXPORT_SYMBOL_GPL(mtd_erase_callback);
263 
264 static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
265 {
266 	struct mtd_part *part = PART(mtd);
267 	if ((len + ofs) > mtd->size)
268 		return -EINVAL;
269 	return part->master->lock(part->master, ofs + part->offset, len);
270 }
271 
272 static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
273 {
274 	struct mtd_part *part = PART(mtd);
275 	if ((len + ofs) > mtd->size)
276 		return -EINVAL;
277 	return part->master->unlock(part->master, ofs + part->offset, len);
278 }
279 
280 static int part_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
281 {
282 	struct mtd_part *part = PART(mtd);
283 	if ((len + ofs) > mtd->size)
284 		return -EINVAL;
285 	return part->master->is_locked(part->master, ofs + part->offset, len);
286 }
287 
288 static void part_sync(struct mtd_info *mtd)
289 {
290 	struct mtd_part *part = PART(mtd);
291 	part->master->sync(part->master);
292 }
293 
294 static int part_suspend(struct mtd_info *mtd)
295 {
296 	struct mtd_part *part = PART(mtd);
297 	return part->master->suspend(part->master);
298 }
299 
300 static void part_resume(struct mtd_info *mtd)
301 {
302 	struct mtd_part *part = PART(mtd);
303 	part->master->resume(part->master);
304 }
305 
306 static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
307 {
308 	struct mtd_part *part = PART(mtd);
309 	if (ofs >= mtd->size)
310 		return -EINVAL;
311 	ofs += part->offset;
312 	return part->master->block_isbad(part->master, ofs);
313 }
314 
315 static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
316 {
317 	struct mtd_part *part = PART(mtd);
318 	int res;
319 
320 	if (!(mtd->flags & MTD_WRITEABLE))
321 		return -EROFS;
322 	if (ofs >= mtd->size)
323 		return -EINVAL;
324 	ofs += part->offset;
325 	res = part->master->block_markbad(part->master, ofs);
326 	if (!res)
327 		mtd->ecc_stats.badblocks++;
328 	return res;
329 }
330 
331 static inline void free_partition(struct mtd_part *p)
332 {
333 	kfree(p->mtd.name);
334 	kfree(p);
335 }
336 
337 /*
338  * This function unregisters and destroy all slave MTD objects which are
339  * attached to the given master MTD object.
340  */
341 
342 int del_mtd_partitions(struct mtd_info *master)
343 {
344 	struct mtd_part *slave, *next;
345 	int ret, err = 0;
346 
347 	mutex_lock(&mtd_partitions_mutex);
348 	list_for_each_entry_safe(slave, next, &mtd_partitions, list)
349 		if (slave->master == master) {
350 			ret = del_mtd_device(&slave->mtd);
351 			if (ret < 0) {
352 				err = ret;
353 				continue;
354 			}
355 			list_del(&slave->list);
356 			free_partition(slave);
357 		}
358 	mutex_unlock(&mtd_partitions_mutex);
359 
360 	return err;
361 }
362 EXPORT_SYMBOL(del_mtd_partitions);
363 
364 static struct mtd_part *allocate_partition(struct mtd_info *master,
365 			const struct mtd_partition *part, int partno,
366 			uint64_t cur_offset)
367 {
368 	struct mtd_part *slave;
369 	char *name;
370 
371 	/* allocate the partition structure */
372 	slave = kzalloc(sizeof(*slave), GFP_KERNEL);
373 	name = kstrdup(part->name, GFP_KERNEL);
374 	if (!name || !slave) {
375 		printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
376 		       master->name);
377 		kfree(name);
378 		kfree(slave);
379 		return ERR_PTR(-ENOMEM);
380 	}
381 
382 	/* set up the MTD object for this partition */
383 	slave->mtd.type = master->type;
384 	slave->mtd.flags = master->flags & ~part->mask_flags;
385 	slave->mtd.size = part->size;
386 	slave->mtd.writesize = master->writesize;
387 	slave->mtd.oobsize = master->oobsize;
388 	slave->mtd.oobavail = master->oobavail;
389 	slave->mtd.subpage_sft = master->subpage_sft;
390 
391 	slave->mtd.name = name;
392 	slave->mtd.owner = master->owner;
393 	slave->mtd.backing_dev_info = master->backing_dev_info;
394 
395 	/* NOTE:  we don't arrange MTDs as a tree; it'd be error-prone
396 	 * to have the same data be in two different partitions.
397 	 */
398 	slave->mtd.dev.parent = master->dev.parent;
399 
400 	slave->mtd.read = part_read;
401 	slave->mtd.write = part_write;
402 
403 	if (master->panic_write)
404 		slave->mtd.panic_write = part_panic_write;
405 
406 	if (master->point && master->unpoint) {
407 		slave->mtd.point = part_point;
408 		slave->mtd.unpoint = part_unpoint;
409 	}
410 
411 	if (master->get_unmapped_area)
412 		slave->mtd.get_unmapped_area = part_get_unmapped_area;
413 	if (master->read_oob)
414 		slave->mtd.read_oob = part_read_oob;
415 	if (master->write_oob)
416 		slave->mtd.write_oob = part_write_oob;
417 	if (master->read_user_prot_reg)
418 		slave->mtd.read_user_prot_reg = part_read_user_prot_reg;
419 	if (master->read_fact_prot_reg)
420 		slave->mtd.read_fact_prot_reg = part_read_fact_prot_reg;
421 	if (master->write_user_prot_reg)
422 		slave->mtd.write_user_prot_reg = part_write_user_prot_reg;
423 	if (master->lock_user_prot_reg)
424 		slave->mtd.lock_user_prot_reg = part_lock_user_prot_reg;
425 	if (master->get_user_prot_info)
426 		slave->mtd.get_user_prot_info = part_get_user_prot_info;
427 	if (master->get_fact_prot_info)
428 		slave->mtd.get_fact_prot_info = part_get_fact_prot_info;
429 	if (master->sync)
430 		slave->mtd.sync = part_sync;
431 	if (!partno && !master->dev.class && master->suspend && master->resume) {
432 			slave->mtd.suspend = part_suspend;
433 			slave->mtd.resume = part_resume;
434 	}
435 	if (master->writev)
436 		slave->mtd.writev = part_writev;
437 	if (master->lock)
438 		slave->mtd.lock = part_lock;
439 	if (master->unlock)
440 		slave->mtd.unlock = part_unlock;
441 	if (master->is_locked)
442 		slave->mtd.is_locked = part_is_locked;
443 	if (master->block_isbad)
444 		slave->mtd.block_isbad = part_block_isbad;
445 	if (master->block_markbad)
446 		slave->mtd.block_markbad = part_block_markbad;
447 	slave->mtd.erase = part_erase;
448 	slave->master = master;
449 	slave->offset = part->offset;
450 
451 	if (slave->offset == MTDPART_OFS_APPEND)
452 		slave->offset = cur_offset;
453 	if (slave->offset == MTDPART_OFS_NXTBLK) {
454 		slave->offset = cur_offset;
455 		if (mtd_mod_by_eb(cur_offset, master) != 0) {
456 			/* Round up to next erasesize */
457 			slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
458 			printk(KERN_NOTICE "Moving partition %d: "
459 			       "0x%012llx -> 0x%012llx\n", partno,
460 			       (unsigned long long)cur_offset, (unsigned long long)slave->offset);
461 		}
462 	}
463 	if (slave->mtd.size == MTDPART_SIZ_FULL)
464 		slave->mtd.size = master->size - slave->offset;
465 
466 	printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
467 		(unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
468 
469 	/* let's do some sanity checks */
470 	if (slave->offset >= master->size) {
471 		/* let's register it anyway to preserve ordering */
472 		slave->offset = 0;
473 		slave->mtd.size = 0;
474 		printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
475 			part->name);
476 		goto out_register;
477 	}
478 	if (slave->offset + slave->mtd.size > master->size) {
479 		slave->mtd.size = master->size - slave->offset;
480 		printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
481 			part->name, master->name, (unsigned long long)slave->mtd.size);
482 	}
483 	if (master->numeraseregions > 1) {
484 		/* Deal with variable erase size stuff */
485 		int i, max = master->numeraseregions;
486 		u64 end = slave->offset + slave->mtd.size;
487 		struct mtd_erase_region_info *regions = master->eraseregions;
488 
489 		/* Find the first erase regions which is part of this
490 		 * partition. */
491 		for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
492 			;
493 		/* The loop searched for the region _behind_ the first one */
494 		if (i > 0)
495 			i--;
496 
497 		/* Pick biggest erasesize */
498 		for (; i < max && regions[i].offset < end; i++) {
499 			if (slave->mtd.erasesize < regions[i].erasesize) {
500 				slave->mtd.erasesize = regions[i].erasesize;
501 			}
502 		}
503 		BUG_ON(slave->mtd.erasesize == 0);
504 	} else {
505 		/* Single erase size */
506 		slave->mtd.erasesize = master->erasesize;
507 	}
508 
509 	if ((slave->mtd.flags & MTD_WRITEABLE) &&
510 	    mtd_mod_by_eb(slave->offset, &slave->mtd)) {
511 		/* Doesn't start on a boundary of major erase size */
512 		/* FIXME: Let it be writable if it is on a boundary of
513 		 * _minor_ erase size though */
514 		slave->mtd.flags &= ~MTD_WRITEABLE;
515 		printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
516 			part->name);
517 	}
518 	if ((slave->mtd.flags & MTD_WRITEABLE) &&
519 	    mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) {
520 		slave->mtd.flags &= ~MTD_WRITEABLE;
521 		printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
522 			part->name);
523 	}
524 
525 	slave->mtd.ecclayout = master->ecclayout;
526 	if (master->block_isbad) {
527 		uint64_t offs = 0;
528 
529 		while (offs < slave->mtd.size) {
530 			if (master->block_isbad(master,
531 						offs + slave->offset))
532 				slave->mtd.ecc_stats.badblocks++;
533 			offs += slave->mtd.erasesize;
534 		}
535 	}
536 
537 out_register:
538 	return slave;
539 }
540 
541 int mtd_add_partition(struct mtd_info *master, char *name,
542 		      long long offset, long long length)
543 {
544 	struct mtd_partition part;
545 	struct mtd_part *p, *new;
546 	uint64_t start, end;
547 	int ret = 0;
548 
549 	/* the direct offset is expected */
550 	if (offset == MTDPART_OFS_APPEND ||
551 	    offset == MTDPART_OFS_NXTBLK)
552 		return -EINVAL;
553 
554 	if (length == MTDPART_SIZ_FULL)
555 		length = master->size - offset;
556 
557 	if (length <= 0)
558 		return -EINVAL;
559 
560 	part.name = name;
561 	part.size = length;
562 	part.offset = offset;
563 	part.mask_flags = 0;
564 	part.ecclayout = NULL;
565 
566 	new = allocate_partition(master, &part, -1, offset);
567 	if (IS_ERR(new))
568 		return PTR_ERR(new);
569 
570 	start = offset;
571 	end = offset + length;
572 
573 	mutex_lock(&mtd_partitions_mutex);
574 	list_for_each_entry(p, &mtd_partitions, list)
575 		if (p->master == master) {
576 			if ((start >= p->offset) &&
577 			    (start < (p->offset + p->mtd.size)))
578 				goto err_inv;
579 
580 			if ((end >= p->offset) &&
581 			    (end < (p->offset + p->mtd.size)))
582 				goto err_inv;
583 		}
584 
585 	list_add(&new->list, &mtd_partitions);
586 	mutex_unlock(&mtd_partitions_mutex);
587 
588 	add_mtd_device(&new->mtd);
589 
590 	return ret;
591 err_inv:
592 	mutex_unlock(&mtd_partitions_mutex);
593 	free_partition(new);
594 	return -EINVAL;
595 }
596 EXPORT_SYMBOL_GPL(mtd_add_partition);
597 
598 int mtd_del_partition(struct mtd_info *master, int partno)
599 {
600 	struct mtd_part *slave, *next;
601 	int ret = -EINVAL;
602 
603 	mutex_lock(&mtd_partitions_mutex);
604 	list_for_each_entry_safe(slave, next, &mtd_partitions, list)
605 		if ((slave->master == master) &&
606 		    (slave->mtd.index == partno)) {
607 			ret = del_mtd_device(&slave->mtd);
608 			if (ret < 0)
609 				break;
610 
611 			list_del(&slave->list);
612 			free_partition(slave);
613 			break;
614 		}
615 	mutex_unlock(&mtd_partitions_mutex);
616 
617 	return ret;
618 }
619 EXPORT_SYMBOL_GPL(mtd_del_partition);
620 
621 /*
622  * This function, given a master MTD object and a partition table, creates
623  * and registers slave MTD objects which are bound to the master according to
624  * the partition definitions.
625  *
626  * We don't register the master, or expect the caller to have done so,
627  * for reasons of data integrity.
628  */
629 
630 int add_mtd_partitions(struct mtd_info *master,
631 		       const struct mtd_partition *parts,
632 		       int nbparts)
633 {
634 	struct mtd_part *slave;
635 	uint64_t cur_offset = 0;
636 	int i;
637 
638 	printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
639 
640 	for (i = 0; i < nbparts; i++) {
641 		slave = allocate_partition(master, parts + i, i, cur_offset);
642 		if (IS_ERR(slave))
643 			return PTR_ERR(slave);
644 
645 		mutex_lock(&mtd_partitions_mutex);
646 		list_add(&slave->list, &mtd_partitions);
647 		mutex_unlock(&mtd_partitions_mutex);
648 
649 		add_mtd_device(&slave->mtd);
650 
651 		cur_offset = slave->offset + slave->mtd.size;
652 	}
653 
654 	return 0;
655 }
656 EXPORT_SYMBOL(add_mtd_partitions);
657 
658 static DEFINE_SPINLOCK(part_parser_lock);
659 static LIST_HEAD(part_parsers);
660 
661 static struct mtd_part_parser *get_partition_parser(const char *name)
662 {
663 	struct mtd_part_parser *p, *ret = NULL;
664 
665 	spin_lock(&part_parser_lock);
666 
667 	list_for_each_entry(p, &part_parsers, list)
668 		if (!strcmp(p->name, name) && try_module_get(p->owner)) {
669 			ret = p;
670 			break;
671 		}
672 
673 	spin_unlock(&part_parser_lock);
674 
675 	return ret;
676 }
677 
678 int register_mtd_parser(struct mtd_part_parser *p)
679 {
680 	spin_lock(&part_parser_lock);
681 	list_add(&p->list, &part_parsers);
682 	spin_unlock(&part_parser_lock);
683 
684 	return 0;
685 }
686 EXPORT_SYMBOL_GPL(register_mtd_parser);
687 
688 int deregister_mtd_parser(struct mtd_part_parser *p)
689 {
690 	spin_lock(&part_parser_lock);
691 	list_del(&p->list);
692 	spin_unlock(&part_parser_lock);
693 	return 0;
694 }
695 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
696 
697 int parse_mtd_partitions(struct mtd_info *master, const char **types,
698 			 struct mtd_partition **pparts, unsigned long origin)
699 {
700 	struct mtd_part_parser *parser;
701 	int ret = 0;
702 
703 	for ( ; ret <= 0 && *types; types++) {
704 		parser = get_partition_parser(*types);
705 		if (!parser && !request_module("%s", *types))
706 				parser = get_partition_parser(*types);
707 		if (!parser) {
708 			printk(KERN_NOTICE "%s partition parsing not available\n",
709 			       *types);
710 			continue;
711 		}
712 		ret = (*parser->parse_fn)(master, pparts, origin);
713 		if (ret > 0) {
714 			printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
715 			       ret, parser->name, master->name);
716 		}
717 		put_partition_parser(parser);
718 	}
719 	return ret;
720 }
721 EXPORT_SYMBOL_GPL(parse_mtd_partitions);
722 
723 int mtd_is_master(struct mtd_info *mtd)
724 {
725 	struct mtd_part *part;
726 	int nopart = 0;
727 
728 	mutex_lock(&mtd_partitions_mutex);
729 	list_for_each_entry(part, &mtd_partitions, list)
730 		if (&part->mtd == mtd) {
731 			nopart = 1;
732 			break;
733 		}
734 	mutex_unlock(&mtd_partitions_mutex);
735 
736 	return nopart;
737 }
738 EXPORT_SYMBOL_GPL(mtd_is_master);
739