xref: /openbmc/u-boot/drivers/mtd/mtdpart.c (revision ddf7bcfa)
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  * SPDX-License-Identifier:	GPL-2.0+
9  *
10  */
11 
12 #define __UBOOT__
13 #ifndef __UBOOT__
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 #endif
21 
22 #include <common.h>
23 #include <malloc.h>
24 #include <asm/errno.h>
25 #include <linux/compat.h>
26 #include <ubi_uboot.h>
27 
28 #include <linux/mtd/mtd.h>
29 #include <linux/mtd/partitions.h>
30 #include <linux/err.h>
31 
32 #include "mtdcore.h"
33 
34 /* Our partition linked list */
35 static LIST_HEAD(mtd_partitions);
36 #ifndef __UBOOT__
37 static DEFINE_MUTEX(mtd_partitions_mutex);
38 #else
39 DEFINE_MUTEX(mtd_partitions_mutex);
40 #endif
41 
42 /* Our partition node structure */
43 struct mtd_part {
44 	struct mtd_info mtd;
45 	struct mtd_info *master;
46 	uint64_t offset;
47 	struct list_head list;
48 };
49 
50 /*
51  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
52  * the pointer to that structure with this macro.
53  */
54 #define PART(x)  ((struct mtd_part *)(x))
55 
56 
57 #ifdef __UBOOT__
58 /* from mm/util.c */
59 
60 /**
61  * kstrdup - allocate space for and copy an existing string
62  * @s: the string to duplicate
63  * @gfp: the GFP mask used in the kmalloc() call when allocating memory
64  */
65 char *kstrdup(const char *s, gfp_t gfp)
66 {
67 	size_t len;
68 	char *buf;
69 
70 	if (!s)
71 		return NULL;
72 
73 	len = strlen(s) + 1;
74 	buf = kmalloc(len, gfp);
75 	if (buf)
76 		memcpy(buf, s, len);
77 	return buf;
78 }
79 #endif
80 
81 /*
82  * MTD methods which simply translate the effective address and pass through
83  * to the _real_ device.
84  */
85 
86 static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
87 		size_t *retlen, u_char *buf)
88 {
89 	struct mtd_part *part = PART(mtd);
90 	struct mtd_ecc_stats stats;
91 	int res;
92 
93 	stats = part->master->ecc_stats;
94 	res = part->master->_read(part->master, from + part->offset, len,
95 				  retlen, buf);
96 	if (unlikely(mtd_is_eccerr(res)))
97 		mtd->ecc_stats.failed +=
98 			part->master->ecc_stats.failed - stats.failed;
99 	else
100 		mtd->ecc_stats.corrected +=
101 			part->master->ecc_stats.corrected - stats.corrected;
102 	return res;
103 }
104 
105 #ifndef __UBOOT__
106 static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
107 		size_t *retlen, void **virt, resource_size_t *phys)
108 {
109 	struct mtd_part *part = PART(mtd);
110 
111 	return part->master->_point(part->master, from + part->offset, len,
112 				    retlen, virt, phys);
113 }
114 
115 static int part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
116 {
117 	struct mtd_part *part = PART(mtd);
118 
119 	return part->master->_unpoint(part->master, from + part->offset, len);
120 }
121 #endif
122 
123 static unsigned long part_get_unmapped_area(struct mtd_info *mtd,
124 					    unsigned long len,
125 					    unsigned long offset,
126 					    unsigned long flags)
127 {
128 	struct mtd_part *part = PART(mtd);
129 
130 	offset += part->offset;
131 	return part->master->_get_unmapped_area(part->master, len, offset,
132 						flags);
133 }
134 
135 static int part_read_oob(struct mtd_info *mtd, loff_t from,
136 		struct mtd_oob_ops *ops)
137 {
138 	struct mtd_part *part = PART(mtd);
139 	int res;
140 
141 	if (from >= mtd->size)
142 		return -EINVAL;
143 	if (ops->datbuf && from + ops->len > mtd->size)
144 		return -EINVAL;
145 
146 	/*
147 	 * If OOB is also requested, make sure that we do not read past the end
148 	 * of this partition.
149 	 */
150 	if (ops->oobbuf) {
151 		size_t len, pages;
152 
153 		if (ops->mode == MTD_OPS_AUTO_OOB)
154 			len = mtd->oobavail;
155 		else
156 			len = mtd->oobsize;
157 		pages = mtd_div_by_ws(mtd->size, mtd);
158 		pages -= mtd_div_by_ws(from, mtd);
159 		if (ops->ooboffs + ops->ooblen > pages * len)
160 			return -EINVAL;
161 	}
162 
163 	res = part->master->_read_oob(part->master, from + part->offset, ops);
164 	if (unlikely(res)) {
165 		if (mtd_is_bitflip(res))
166 			mtd->ecc_stats.corrected++;
167 		if (mtd_is_eccerr(res))
168 			mtd->ecc_stats.failed++;
169 	}
170 	return res;
171 }
172 
173 static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
174 		size_t len, size_t *retlen, u_char *buf)
175 {
176 	struct mtd_part *part = PART(mtd);
177 	return part->master->_read_user_prot_reg(part->master, from, len,
178 						 retlen, buf);
179 }
180 
181 static int part_get_user_prot_info(struct mtd_info *mtd,
182 		struct otp_info *buf, size_t len)
183 {
184 	struct mtd_part *part = PART(mtd);
185 	return part->master->_get_user_prot_info(part->master, buf, len);
186 }
187 
188 static int part_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
189 		size_t len, size_t *retlen, u_char *buf)
190 {
191 	struct mtd_part *part = PART(mtd);
192 	return part->master->_read_fact_prot_reg(part->master, from, len,
193 						 retlen, buf);
194 }
195 
196 static int part_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
197 		size_t len)
198 {
199 	struct mtd_part *part = PART(mtd);
200 	return part->master->_get_fact_prot_info(part->master, buf, len);
201 }
202 
203 static int part_write(struct mtd_info *mtd, loff_t to, size_t len,
204 		size_t *retlen, const u_char *buf)
205 {
206 	struct mtd_part *part = PART(mtd);
207 	return part->master->_write(part->master, to + part->offset, len,
208 				    retlen, buf);
209 }
210 
211 static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
212 		size_t *retlen, const u_char *buf)
213 {
214 	struct mtd_part *part = PART(mtd);
215 	return part->master->_panic_write(part->master, to + part->offset, len,
216 					  retlen, buf);
217 }
218 
219 static int part_write_oob(struct mtd_info *mtd, loff_t to,
220 		struct mtd_oob_ops *ops)
221 {
222 	struct mtd_part *part = PART(mtd);
223 
224 	if (to >= mtd->size)
225 		return -EINVAL;
226 	if (ops->datbuf && to + ops->len > mtd->size)
227 		return -EINVAL;
228 	return part->master->_write_oob(part->master, to + part->offset, ops);
229 }
230 
231 static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
232 		size_t len, size_t *retlen, u_char *buf)
233 {
234 	struct mtd_part *part = PART(mtd);
235 	return part->master->_write_user_prot_reg(part->master, from, len,
236 						  retlen, buf);
237 }
238 
239 static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
240 		size_t len)
241 {
242 	struct mtd_part *part = PART(mtd);
243 	return part->master->_lock_user_prot_reg(part->master, from, len);
244 }
245 
246 #ifndef __UBOOT__
247 static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,
248 		unsigned long count, loff_t to, size_t *retlen)
249 {
250 	struct mtd_part *part = PART(mtd);
251 	return part->master->_writev(part->master, vecs, count,
252 				     to + part->offset, retlen);
253 }
254 #endif
255 
256 static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
257 {
258 	struct mtd_part *part = PART(mtd);
259 	int ret;
260 
261 	instr->addr += part->offset;
262 	ret = part->master->_erase(part->master, instr);
263 	if (ret) {
264 		if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
265 			instr->fail_addr -= part->offset;
266 		instr->addr -= part->offset;
267 	}
268 	return ret;
269 }
270 
271 void mtd_erase_callback(struct erase_info *instr)
272 {
273 	if (instr->mtd->_erase == part_erase) {
274 		struct mtd_part *part = PART(instr->mtd);
275 
276 		if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
277 			instr->fail_addr -= part->offset;
278 		instr->addr -= part->offset;
279 	}
280 	if (instr->callback)
281 		instr->callback(instr);
282 }
283 EXPORT_SYMBOL_GPL(mtd_erase_callback);
284 
285 static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
286 {
287 	struct mtd_part *part = PART(mtd);
288 	return part->master->_lock(part->master, ofs + part->offset, len);
289 }
290 
291 static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
292 {
293 	struct mtd_part *part = PART(mtd);
294 	return part->master->_unlock(part->master, ofs + part->offset, len);
295 }
296 
297 static int part_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
298 {
299 	struct mtd_part *part = PART(mtd);
300 	return part->master->_is_locked(part->master, ofs + part->offset, len);
301 }
302 
303 static void part_sync(struct mtd_info *mtd)
304 {
305 	struct mtd_part *part = PART(mtd);
306 	part->master->_sync(part->master);
307 }
308 
309 #ifndef __UBOOT__
310 static int part_suspend(struct mtd_info *mtd)
311 {
312 	struct mtd_part *part = PART(mtd);
313 	return part->master->_suspend(part->master);
314 }
315 
316 static void part_resume(struct mtd_info *mtd)
317 {
318 	struct mtd_part *part = PART(mtd);
319 	part->master->_resume(part->master);
320 }
321 #endif
322 
323 static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
324 {
325 	struct mtd_part *part = PART(mtd);
326 	ofs += part->offset;
327 	return part->master->_block_isbad(part->master, ofs);
328 }
329 
330 static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
331 {
332 	struct mtd_part *part = PART(mtd);
333 	int res;
334 
335 	ofs += part->offset;
336 	res = part->master->_block_markbad(part->master, ofs);
337 	if (!res)
338 		mtd->ecc_stats.badblocks++;
339 	return res;
340 }
341 
342 static inline void free_partition(struct mtd_part *p)
343 {
344 	kfree(p->mtd.name);
345 	kfree(p);
346 }
347 
348 /*
349  * This function unregisters and destroy all slave MTD objects which are
350  * attached to the given master MTD object.
351  */
352 
353 int del_mtd_partitions(struct mtd_info *master)
354 {
355 	struct mtd_part *slave, *next;
356 	int ret, err = 0;
357 
358 	mutex_lock(&mtd_partitions_mutex);
359 	list_for_each_entry_safe(slave, next, &mtd_partitions, list)
360 		if (slave->master == master) {
361 			ret = del_mtd_device(&slave->mtd);
362 			if (ret < 0) {
363 				err = ret;
364 				continue;
365 			}
366 			list_del(&slave->list);
367 			free_partition(slave);
368 		}
369 	mutex_unlock(&mtd_partitions_mutex);
370 
371 	return err;
372 }
373 
374 static struct mtd_part *allocate_partition(struct mtd_info *master,
375 			const struct mtd_partition *part, int partno,
376 			uint64_t cur_offset)
377 {
378 	struct mtd_part *slave;
379 	char *name;
380 
381 	/* allocate the partition structure */
382 	slave = kzalloc(sizeof(*slave), GFP_KERNEL);
383 	name = kstrdup(part->name, GFP_KERNEL);
384 	if (!name || !slave) {
385 		printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
386 		       master->name);
387 		kfree(name);
388 		kfree(slave);
389 		return ERR_PTR(-ENOMEM);
390 	}
391 
392 	/* set up the MTD object for this partition */
393 	slave->mtd.type = master->type;
394 	slave->mtd.flags = master->flags & ~part->mask_flags;
395 	slave->mtd.size = part->size;
396 	slave->mtd.writesize = master->writesize;
397 	slave->mtd.writebufsize = master->writebufsize;
398 	slave->mtd.oobsize = master->oobsize;
399 	slave->mtd.oobavail = master->oobavail;
400 	slave->mtd.subpage_sft = master->subpage_sft;
401 
402 	slave->mtd.name = name;
403 	slave->mtd.owner = master->owner;
404 #ifndef __UBOOT__
405 	slave->mtd.backing_dev_info = master->backing_dev_info;
406 
407 	/* NOTE:  we don't arrange MTDs as a tree; it'd be error-prone
408 	 * to have the same data be in two different partitions.
409 	 */
410 	slave->mtd.dev.parent = master->dev.parent;
411 #endif
412 
413 	slave->mtd._read = part_read;
414 	slave->mtd._write = part_write;
415 
416 	if (master->_panic_write)
417 		slave->mtd._panic_write = part_panic_write;
418 
419 #ifndef __UBOOT__
420 	if (master->_point && master->_unpoint) {
421 		slave->mtd._point = part_point;
422 		slave->mtd._unpoint = part_unpoint;
423 	}
424 #endif
425 
426 	if (master->_get_unmapped_area)
427 		slave->mtd._get_unmapped_area = part_get_unmapped_area;
428 	if (master->_read_oob)
429 		slave->mtd._read_oob = part_read_oob;
430 	if (master->_write_oob)
431 		slave->mtd._write_oob = part_write_oob;
432 	if (master->_read_user_prot_reg)
433 		slave->mtd._read_user_prot_reg = part_read_user_prot_reg;
434 	if (master->_read_fact_prot_reg)
435 		slave->mtd._read_fact_prot_reg = part_read_fact_prot_reg;
436 	if (master->_write_user_prot_reg)
437 		slave->mtd._write_user_prot_reg = part_write_user_prot_reg;
438 	if (master->_lock_user_prot_reg)
439 		slave->mtd._lock_user_prot_reg = part_lock_user_prot_reg;
440 	if (master->_get_user_prot_info)
441 		slave->mtd._get_user_prot_info = part_get_user_prot_info;
442 	if (master->_get_fact_prot_info)
443 		slave->mtd._get_fact_prot_info = part_get_fact_prot_info;
444 	if (master->_sync)
445 		slave->mtd._sync = part_sync;
446 #ifndef __UBOOT__
447 	if (!partno && !master->dev.class && master->_suspend &&
448 	    master->_resume) {
449 			slave->mtd._suspend = part_suspend;
450 			slave->mtd._resume = part_resume;
451 	}
452 	if (master->_writev)
453 		slave->mtd._writev = part_writev;
454 #endif
455 	if (master->_lock)
456 		slave->mtd._lock = part_lock;
457 	if (master->_unlock)
458 		slave->mtd._unlock = part_unlock;
459 	if (master->_is_locked)
460 		slave->mtd._is_locked = part_is_locked;
461 	if (master->_block_isbad)
462 		slave->mtd._block_isbad = part_block_isbad;
463 	if (master->_block_markbad)
464 		slave->mtd._block_markbad = part_block_markbad;
465 	slave->mtd._erase = part_erase;
466 	slave->master = master;
467 	slave->offset = part->offset;
468 
469 	if (slave->offset == MTDPART_OFS_APPEND)
470 		slave->offset = cur_offset;
471 	if (slave->offset == MTDPART_OFS_NXTBLK) {
472 		slave->offset = cur_offset;
473 		if (mtd_mod_by_eb(cur_offset, master) != 0) {
474 			/* Round up to next erasesize */
475 			slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
476 			debug("Moving partition %d: "
477 			       "0x%012llx -> 0x%012llx\n", partno,
478 			       (unsigned long long)cur_offset, (unsigned long long)slave->offset);
479 		}
480 	}
481 	if (slave->offset == MTDPART_OFS_RETAIN) {
482 		slave->offset = cur_offset;
483 		if (master->size - slave->offset >= slave->mtd.size) {
484 			slave->mtd.size = master->size - slave->offset
485 							- slave->mtd.size;
486 		} else {
487 			debug("mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n",
488 				part->name, master->size - slave->offset,
489 				slave->mtd.size);
490 			/* register to preserve ordering */
491 			goto out_register;
492 		}
493 	}
494 	if (slave->mtd.size == MTDPART_SIZ_FULL)
495 		slave->mtd.size = master->size - slave->offset;
496 
497 	debug("0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
498 		(unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
499 
500 	/* let's do some sanity checks */
501 	if (slave->offset >= master->size) {
502 		/* let's register it anyway to preserve ordering */
503 		slave->offset = 0;
504 		slave->mtd.size = 0;
505 		printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
506 			part->name);
507 		goto out_register;
508 	}
509 	if (slave->offset + slave->mtd.size > master->size) {
510 		slave->mtd.size = master->size - slave->offset;
511 		printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
512 			part->name, master->name, (unsigned long long)slave->mtd.size);
513 	}
514 	if (master->numeraseregions > 1) {
515 		/* Deal with variable erase size stuff */
516 		int i, max = master->numeraseregions;
517 		u64 end = slave->offset + slave->mtd.size;
518 		struct mtd_erase_region_info *regions = master->eraseregions;
519 
520 		/* Find the first erase regions which is part of this
521 		 * partition. */
522 		for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
523 			;
524 		/* The loop searched for the region _behind_ the first one */
525 		if (i > 0)
526 			i--;
527 
528 		/* Pick biggest erasesize */
529 		for (; i < max && regions[i].offset < end; i++) {
530 			if (slave->mtd.erasesize < regions[i].erasesize) {
531 				slave->mtd.erasesize = regions[i].erasesize;
532 			}
533 		}
534 		BUG_ON(slave->mtd.erasesize == 0);
535 	} else {
536 		/* Single erase size */
537 		slave->mtd.erasesize = master->erasesize;
538 	}
539 
540 	if ((slave->mtd.flags & MTD_WRITEABLE) &&
541 	    mtd_mod_by_eb(slave->offset, &slave->mtd)) {
542 		/* Doesn't start on a boundary of major erase size */
543 		/* FIXME: Let it be writable if it is on a boundary of
544 		 * _minor_ erase size though */
545 		slave->mtd.flags &= ~MTD_WRITEABLE;
546 		printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
547 			part->name);
548 	}
549 	if ((slave->mtd.flags & MTD_WRITEABLE) &&
550 	    mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) {
551 		slave->mtd.flags &= ~MTD_WRITEABLE;
552 		printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
553 			part->name);
554 	}
555 
556 	slave->mtd.ecclayout = master->ecclayout;
557 	slave->mtd.ecc_step_size = master->ecc_step_size;
558 	slave->mtd.ecc_strength = master->ecc_strength;
559 	slave->mtd.bitflip_threshold = master->bitflip_threshold;
560 
561 	if (master->_block_isbad) {
562 		uint64_t offs = 0;
563 
564 		while (offs < slave->mtd.size) {
565 			if (mtd_block_isbad(master, offs + slave->offset))
566 				slave->mtd.ecc_stats.badblocks++;
567 			offs += slave->mtd.erasesize;
568 		}
569 	}
570 
571 out_register:
572 	return slave;
573 }
574 
575 #ifndef __UBOOT__
576 int mtd_add_partition(struct mtd_info *master, const char *name,
577 		      long long offset, long long length)
578 {
579 	struct mtd_partition part;
580 	struct mtd_part *p, *new;
581 	uint64_t start, end;
582 	int ret = 0;
583 
584 	/* the direct offset is expected */
585 	if (offset == MTDPART_OFS_APPEND ||
586 	    offset == MTDPART_OFS_NXTBLK)
587 		return -EINVAL;
588 
589 	if (length == MTDPART_SIZ_FULL)
590 		length = master->size - offset;
591 
592 	if (length <= 0)
593 		return -EINVAL;
594 
595 	part.name = name;
596 	part.size = length;
597 	part.offset = offset;
598 	part.mask_flags = 0;
599 	part.ecclayout = NULL;
600 
601 	new = allocate_partition(master, &part, -1, offset);
602 	if (IS_ERR(new))
603 		return PTR_ERR(new);
604 
605 	start = offset;
606 	end = offset + length;
607 
608 	mutex_lock(&mtd_partitions_mutex);
609 	list_for_each_entry(p, &mtd_partitions, list)
610 		if (p->master == master) {
611 			if ((start >= p->offset) &&
612 			    (start < (p->offset + p->mtd.size)))
613 				goto err_inv;
614 
615 			if ((end >= p->offset) &&
616 			    (end < (p->offset + p->mtd.size)))
617 				goto err_inv;
618 		}
619 
620 	list_add(&new->list, &mtd_partitions);
621 	mutex_unlock(&mtd_partitions_mutex);
622 
623 	add_mtd_device(&new->mtd);
624 
625 	return ret;
626 err_inv:
627 	mutex_unlock(&mtd_partitions_mutex);
628 	free_partition(new);
629 	return -EINVAL;
630 }
631 EXPORT_SYMBOL_GPL(mtd_add_partition);
632 
633 int mtd_del_partition(struct mtd_info *master, int partno)
634 {
635 	struct mtd_part *slave, *next;
636 	int ret = -EINVAL;
637 
638 	mutex_lock(&mtd_partitions_mutex);
639 	list_for_each_entry_safe(slave, next, &mtd_partitions, list)
640 		if ((slave->master == master) &&
641 		    (slave->mtd.index == partno)) {
642 			ret = del_mtd_device(&slave->mtd);
643 			if (ret < 0)
644 				break;
645 
646 			list_del(&slave->list);
647 			free_partition(slave);
648 			break;
649 		}
650 	mutex_unlock(&mtd_partitions_mutex);
651 
652 	return ret;
653 }
654 EXPORT_SYMBOL_GPL(mtd_del_partition);
655 #endif
656 
657 /*
658  * This function, given a master MTD object and a partition table, creates
659  * and registers slave MTD objects which are bound to the master according to
660  * the partition definitions.
661  *
662  * We don't register the master, or expect the caller to have done so,
663  * for reasons of data integrity.
664  */
665 
666 int add_mtd_partitions(struct mtd_info *master,
667 		       const struct mtd_partition *parts,
668 		       int nbparts)
669 {
670 	struct mtd_part *slave;
671 	uint64_t cur_offset = 0;
672 	int i;
673 
674 #ifdef __UBOOT__
675 	/*
676 	 * Need to init the list here, since LIST_INIT() does not
677 	 * work on platforms where relocation has problems (like MIPS
678 	 * & PPC).
679 	 */
680 	if (mtd_partitions.next == NULL)
681 		INIT_LIST_HEAD(&mtd_partitions);
682 #endif
683 
684 	debug("Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
685 
686 	for (i = 0; i < nbparts; i++) {
687 		slave = allocate_partition(master, parts + i, i, cur_offset);
688 		if (IS_ERR(slave))
689 			return PTR_ERR(slave);
690 
691 		mutex_lock(&mtd_partitions_mutex);
692 		list_add(&slave->list, &mtd_partitions);
693 		mutex_unlock(&mtd_partitions_mutex);
694 
695 		add_mtd_device(&slave->mtd);
696 
697 		cur_offset = slave->offset + slave->mtd.size;
698 	}
699 
700 	return 0;
701 }
702 
703 #ifndef __UBOOT__
704 static DEFINE_SPINLOCK(part_parser_lock);
705 static LIST_HEAD(part_parsers);
706 
707 static struct mtd_part_parser *get_partition_parser(const char *name)
708 {
709 	struct mtd_part_parser *p, *ret = NULL;
710 
711 	spin_lock(&part_parser_lock);
712 
713 	list_for_each_entry(p, &part_parsers, list)
714 		if (!strcmp(p->name, name) && try_module_get(p->owner)) {
715 			ret = p;
716 			break;
717 		}
718 
719 	spin_unlock(&part_parser_lock);
720 
721 	return ret;
722 }
723 
724 #define put_partition_parser(p) do { module_put((p)->owner); } while (0)
725 
726 void register_mtd_parser(struct mtd_part_parser *p)
727 {
728 	spin_lock(&part_parser_lock);
729 	list_add(&p->list, &part_parsers);
730 	spin_unlock(&part_parser_lock);
731 }
732 EXPORT_SYMBOL_GPL(register_mtd_parser);
733 
734 void deregister_mtd_parser(struct mtd_part_parser *p)
735 {
736 	spin_lock(&part_parser_lock);
737 	list_del(&p->list);
738 	spin_unlock(&part_parser_lock);
739 }
740 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
741 
742 /*
743  * Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
744  * are changing this array!
745  */
746 static const char * const default_mtd_part_types[] = {
747 	"cmdlinepart",
748 	"ofpart",
749 	NULL
750 };
751 
752 /**
753  * parse_mtd_partitions - parse MTD partitions
754  * @master: the master partition (describes whole MTD device)
755  * @types: names of partition parsers to try or %NULL
756  * @pparts: array of partitions found is returned here
757  * @data: MTD partition parser-specific data
758  *
759  * This function tries to find partition on MTD device @master. It uses MTD
760  * partition parsers, specified in @types. However, if @types is %NULL, then
761  * the default list of parsers is used. The default list contains only the
762  * "cmdlinepart" and "ofpart" parsers ATM.
763  * Note: If there are more then one parser in @types, the kernel only takes the
764  * partitions parsed out by the first parser.
765  *
766  * This function may return:
767  * o a negative error code in case of failure
768  * o zero if no partitions were found
769  * o a positive number of found partitions, in which case on exit @pparts will
770  *   point to an array containing this number of &struct mtd_info objects.
771  */
772 int parse_mtd_partitions(struct mtd_info *master, const char *const *types,
773 			 struct mtd_partition **pparts,
774 			 struct mtd_part_parser_data *data)
775 {
776 	struct mtd_part_parser *parser;
777 	int ret = 0;
778 
779 	if (!types)
780 		types = default_mtd_part_types;
781 
782 	for ( ; ret <= 0 && *types; types++) {
783 		parser = get_partition_parser(*types);
784 		if (!parser && !request_module("%s", *types))
785 			parser = get_partition_parser(*types);
786 		if (!parser)
787 			continue;
788 		ret = (*parser->parse_fn)(master, pparts, data);
789 		put_partition_parser(parser);
790 		if (ret > 0) {
791 			printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
792 			       ret, parser->name, master->name);
793 			break;
794 		}
795 	}
796 	return ret;
797 }
798 #endif
799 
800 int mtd_is_partition(const struct mtd_info *mtd)
801 {
802 	struct mtd_part *part;
803 	int ispart = 0;
804 
805 	mutex_lock(&mtd_partitions_mutex);
806 	list_for_each_entry(part, &mtd_partitions, list)
807 		if (&part->mtd == mtd) {
808 			ispart = 1;
809 			break;
810 		}
811 	mutex_unlock(&mtd_partitions_mutex);
812 
813 	return ispart;
814 }
815 EXPORT_SYMBOL_GPL(mtd_is_partition);
816 
817 /* Returns the size of the entire flash chip */
818 uint64_t mtd_get_device_size(const struct mtd_info *mtd)
819 {
820 	if (!mtd_is_partition(mtd))
821 		return mtd->size;
822 
823 	return PART(mtd)->master->size;
824 }
825 EXPORT_SYMBOL_GPL(mtd_get_device_size);
826