xref: /openbmc/u-boot/drivers/mtd/mtdpart.c (revision 87a62bce)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Simple MTD partitioning layer
4  *
5  * Copyright © 2000 Nicolas Pitre <nico@fluxnic.net>
6  * Copyright © 2002 Thomas Gleixner <gleixner@linutronix.de>
7  * Copyright © 2000-2010 David Woodhouse <dwmw2@infradead.org>
8  *
9  */
10 
11 #ifndef __UBOOT__
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 #endif
19 
20 #include <common.h>
21 #include <malloc.h>
22 #include <linux/errno.h>
23 #include <linux/compat.h>
24 #include <ubi_uboot.h>
25 
26 #include <linux/mtd/mtd.h>
27 #include <linux/mtd/partitions.h>
28 #include <linux/err.h>
29 
30 #include "mtdcore.h"
31 
32 /* Our partition linked list */
33 static LIST_HEAD(mtd_partitions);
34 #ifndef __UBOOT__
35 static DEFINE_MUTEX(mtd_partitions_mutex);
36 #else
37 DEFINE_MUTEX(mtd_partitions_mutex);
38 #endif
39 
40 /* Our partition node structure */
41 struct mtd_part {
42 	struct mtd_info mtd;
43 	struct mtd_info *master;
44 	uint64_t offset;
45 	struct list_head list;
46 };
47 
48 /*
49  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
50  * the pointer to that structure with this macro.
51  */
52 #define PART(x)  ((struct mtd_part *)(x))
53 
54 
55 #ifdef __UBOOT__
56 /* from mm/util.c */
57 
58 /**
59  * kstrdup - allocate space for and copy an existing string
60  * @s: the string to duplicate
61  * @gfp: the GFP mask used in the kmalloc() call when allocating memory
62  */
63 char *kstrdup(const char *s, gfp_t gfp)
64 {
65 	size_t len;
66 	char *buf;
67 
68 	if (!s)
69 		return NULL;
70 
71 	len = strlen(s) + 1;
72 	buf = kmalloc(len, gfp);
73 	if (buf)
74 		memcpy(buf, s, len);
75 	return buf;
76 }
77 #endif
78 
79 /*
80  * MTD methods which simply translate the effective address and pass through
81  * to the _real_ device.
82  */
83 
84 static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
85 		size_t *retlen, u_char *buf)
86 {
87 	struct mtd_part *part = PART(mtd);
88 	struct mtd_ecc_stats stats;
89 	int res;
90 
91 	stats = part->master->ecc_stats;
92 	res = part->master->_read(part->master, from + part->offset, len,
93 				  retlen, buf);
94 	if (unlikely(mtd_is_eccerr(res)))
95 		mtd->ecc_stats.failed +=
96 			part->master->ecc_stats.failed - stats.failed;
97 	else
98 		mtd->ecc_stats.corrected +=
99 			part->master->ecc_stats.corrected - stats.corrected;
100 	return res;
101 }
102 
103 #ifndef __UBOOT__
104 static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
105 		size_t *retlen, void **virt, resource_size_t *phys)
106 {
107 	struct mtd_part *part = PART(mtd);
108 
109 	return part->master->_point(part->master, from + part->offset, len,
110 				    retlen, virt, phys);
111 }
112 
113 static int part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
114 {
115 	struct mtd_part *part = PART(mtd);
116 
117 	return part->master->_unpoint(part->master, from + part->offset, len);
118 }
119 #endif
120 
121 static unsigned long part_get_unmapped_area(struct mtd_info *mtd,
122 					    unsigned long len,
123 					    unsigned long offset,
124 					    unsigned long flags)
125 {
126 	struct mtd_part *part = PART(mtd);
127 
128 	offset += part->offset;
129 	return part->master->_get_unmapped_area(part->master, len, offset,
130 						flags);
131 }
132 
133 static int part_read_oob(struct mtd_info *mtd, loff_t from,
134 		struct mtd_oob_ops *ops)
135 {
136 	struct mtd_part *part = PART(mtd);
137 	int res;
138 
139 	if (from >= mtd->size)
140 		return -EINVAL;
141 	if (ops->datbuf && from + ops->len > mtd->size)
142 		return -EINVAL;
143 
144 	/*
145 	 * If OOB is also requested, make sure that we do not read past the end
146 	 * of this partition.
147 	 */
148 	if (ops->oobbuf) {
149 		size_t len, pages;
150 
151 		if (ops->mode == MTD_OPS_AUTO_OOB)
152 			len = mtd->oobavail;
153 		else
154 			len = mtd->oobsize;
155 		pages = mtd_div_by_ws(mtd->size, mtd);
156 		pages -= mtd_div_by_ws(from, mtd);
157 		if (ops->ooboffs + ops->ooblen > pages * len)
158 			return -EINVAL;
159 	}
160 
161 	res = part->master->_read_oob(part->master, from + part->offset, ops);
162 	if (unlikely(res)) {
163 		if (mtd_is_bitflip(res))
164 			mtd->ecc_stats.corrected++;
165 		if (mtd_is_eccerr(res))
166 			mtd->ecc_stats.failed++;
167 	}
168 	return res;
169 }
170 
171 static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
172 		size_t len, size_t *retlen, u_char *buf)
173 {
174 	struct mtd_part *part = PART(mtd);
175 	return part->master->_read_user_prot_reg(part->master, from, len,
176 						 retlen, buf);
177 }
178 
179 static int part_get_user_prot_info(struct mtd_info *mtd, size_t len,
180 				   size_t *retlen, struct otp_info *buf)
181 {
182 	struct mtd_part *part = PART(mtd);
183 	return part->master->_get_user_prot_info(part->master, len, retlen,
184 						 buf);
185 }
186 
187 static int part_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
188 		size_t len, size_t *retlen, u_char *buf)
189 {
190 	struct mtd_part *part = PART(mtd);
191 	return part->master->_read_fact_prot_reg(part->master, from, len,
192 						 retlen, buf);
193 }
194 
195 static int part_get_fact_prot_info(struct mtd_info *mtd, size_t len,
196 				   size_t *retlen, struct otp_info *buf)
197 {
198 	struct mtd_part *part = PART(mtd);
199 	return part->master->_get_fact_prot_info(part->master, len, retlen,
200 						 buf);
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_isreserved(struct mtd_info *mtd, loff_t ofs)
324 {
325 	struct mtd_part *part = PART(mtd);
326 	ofs += part->offset;
327 	return part->master->_block_isreserved(part->master, ofs);
328 }
329 
330 static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
331 {
332 	struct mtd_part *part = PART(mtd);
333 	ofs += part->offset;
334 	return part->master->_block_isbad(part->master, ofs);
335 }
336 
337 static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
338 {
339 	struct mtd_part *part = PART(mtd);
340 	int res;
341 
342 	ofs += part->offset;
343 	res = part->master->_block_markbad(part->master, ofs);
344 	if (!res)
345 		mtd->ecc_stats.badblocks++;
346 	return res;
347 }
348 
349 static inline void free_partition(struct mtd_part *p)
350 {
351 	kfree(p->mtd.name);
352 	kfree(p);
353 }
354 
355 /*
356  * This function unregisters and destroy all slave MTD objects which are
357  * attached to the given master MTD object.
358  */
359 
360 int del_mtd_partitions(struct mtd_info *master)
361 {
362 	struct mtd_part *slave, *next;
363 	int ret, err = 0;
364 
365 	mutex_lock(&mtd_partitions_mutex);
366 	list_for_each_entry_safe(slave, next, &mtd_partitions, list)
367 		if (slave->master == master) {
368 			ret = del_mtd_device(&slave->mtd);
369 			if (ret < 0) {
370 				err = ret;
371 				continue;
372 			}
373 			list_del(&slave->list);
374 			free_partition(slave);
375 		}
376 	mutex_unlock(&mtd_partitions_mutex);
377 
378 	return err;
379 }
380 
381 static struct mtd_part *allocate_partition(struct mtd_info *master,
382 			const struct mtd_partition *part, int partno,
383 			uint64_t cur_offset)
384 {
385 	struct mtd_part *slave;
386 	char *name;
387 
388 	/* allocate the partition structure */
389 	slave = kzalloc(sizeof(*slave), GFP_KERNEL);
390 	name = kstrdup(part->name, GFP_KERNEL);
391 	if (!name || !slave) {
392 		printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
393 		       master->name);
394 		kfree(name);
395 		kfree(slave);
396 		return ERR_PTR(-ENOMEM);
397 	}
398 
399 	/* set up the MTD object for this partition */
400 	slave->mtd.type = master->type;
401 	slave->mtd.flags = master->flags & ~part->mask_flags;
402 	slave->mtd.size = part->size;
403 	slave->mtd.writesize = master->writesize;
404 	slave->mtd.writebufsize = master->writebufsize;
405 	slave->mtd.oobsize = master->oobsize;
406 	slave->mtd.oobavail = master->oobavail;
407 	slave->mtd.subpage_sft = master->subpage_sft;
408 
409 	slave->mtd.name = name;
410 	slave->mtd.owner = master->owner;
411 #ifndef __UBOOT__
412 	slave->mtd.backing_dev_info = master->backing_dev_info;
413 
414 	/* NOTE:  we don't arrange MTDs as a tree; it'd be error-prone
415 	 * to have the same data be in two different partitions.
416 	 */
417 	slave->mtd.dev.parent = master->dev.parent;
418 #endif
419 
420 	slave->mtd._read = part_read;
421 	slave->mtd._write = part_write;
422 
423 	if (master->_panic_write)
424 		slave->mtd._panic_write = part_panic_write;
425 
426 #ifndef __UBOOT__
427 	if (master->_point && master->_unpoint) {
428 		slave->mtd._point = part_point;
429 		slave->mtd._unpoint = part_unpoint;
430 	}
431 #endif
432 
433 	if (master->_get_unmapped_area)
434 		slave->mtd._get_unmapped_area = part_get_unmapped_area;
435 	if (master->_read_oob)
436 		slave->mtd._read_oob = part_read_oob;
437 	if (master->_write_oob)
438 		slave->mtd._write_oob = part_write_oob;
439 	if (master->_read_user_prot_reg)
440 		slave->mtd._read_user_prot_reg = part_read_user_prot_reg;
441 	if (master->_read_fact_prot_reg)
442 		slave->mtd._read_fact_prot_reg = part_read_fact_prot_reg;
443 	if (master->_write_user_prot_reg)
444 		slave->mtd._write_user_prot_reg = part_write_user_prot_reg;
445 	if (master->_lock_user_prot_reg)
446 		slave->mtd._lock_user_prot_reg = part_lock_user_prot_reg;
447 	if (master->_get_user_prot_info)
448 		slave->mtd._get_user_prot_info = part_get_user_prot_info;
449 	if (master->_get_fact_prot_info)
450 		slave->mtd._get_fact_prot_info = part_get_fact_prot_info;
451 	if (master->_sync)
452 		slave->mtd._sync = part_sync;
453 #ifndef __UBOOT__
454 	if (!partno && !master->dev.class && master->_suspend &&
455 	    master->_resume) {
456 			slave->mtd._suspend = part_suspend;
457 			slave->mtd._resume = part_resume;
458 	}
459 	if (master->_writev)
460 		slave->mtd._writev = part_writev;
461 #endif
462 	if (master->_lock)
463 		slave->mtd._lock = part_lock;
464 	if (master->_unlock)
465 		slave->mtd._unlock = part_unlock;
466 	if (master->_is_locked)
467 		slave->mtd._is_locked = part_is_locked;
468 	if (master->_block_isreserved)
469 		slave->mtd._block_isreserved = part_block_isreserved;
470 	if (master->_block_isbad)
471 		slave->mtd._block_isbad = part_block_isbad;
472 	if (master->_block_markbad)
473 		slave->mtd._block_markbad = part_block_markbad;
474 	slave->mtd._erase = part_erase;
475 	slave->master = master;
476 	slave->offset = part->offset;
477 
478 	if (slave->offset == MTDPART_OFS_APPEND)
479 		slave->offset = cur_offset;
480 	if (slave->offset == MTDPART_OFS_NXTBLK) {
481 		slave->offset = cur_offset;
482 		if (mtd_mod_by_eb(cur_offset, master) != 0) {
483 			/* Round up to next erasesize */
484 			slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
485 			debug("Moving partition %d: "
486 			       "0x%012llx -> 0x%012llx\n", partno,
487 			       (unsigned long long)cur_offset, (unsigned long long)slave->offset);
488 		}
489 	}
490 	if (slave->offset == MTDPART_OFS_RETAIN) {
491 		slave->offset = cur_offset;
492 		if (master->size - slave->offset >= slave->mtd.size) {
493 			slave->mtd.size = master->size - slave->offset
494 							- slave->mtd.size;
495 		} else {
496 			debug("mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n",
497 				part->name, master->size - slave->offset,
498 				slave->mtd.size);
499 			/* register to preserve ordering */
500 			goto out_register;
501 		}
502 	}
503 	if (slave->mtd.size == MTDPART_SIZ_FULL)
504 		slave->mtd.size = master->size - slave->offset;
505 
506 	debug("0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
507 		(unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
508 
509 	/* let's do some sanity checks */
510 	if (slave->offset >= master->size) {
511 		/* let's register it anyway to preserve ordering */
512 		slave->offset = 0;
513 		slave->mtd.size = 0;
514 		printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
515 			part->name);
516 		goto out_register;
517 	}
518 	if (slave->offset + slave->mtd.size > master->size) {
519 		slave->mtd.size = master->size - slave->offset;
520 		printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
521 			part->name, master->name, (unsigned long long)slave->mtd.size);
522 	}
523 	if (master->numeraseregions > 1) {
524 		/* Deal with variable erase size stuff */
525 		int i, max = master->numeraseregions;
526 		u64 end = slave->offset + slave->mtd.size;
527 		struct mtd_erase_region_info *regions = master->eraseregions;
528 
529 		/* Find the first erase regions which is part of this
530 		 * partition. */
531 		for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
532 			;
533 		/* The loop searched for the region _behind_ the first one */
534 		if (i > 0)
535 			i--;
536 
537 		/* Pick biggest erasesize */
538 		for (; i < max && regions[i].offset < end; i++) {
539 			if (slave->mtd.erasesize < regions[i].erasesize) {
540 				slave->mtd.erasesize = regions[i].erasesize;
541 			}
542 		}
543 		BUG_ON(slave->mtd.erasesize == 0);
544 	} else {
545 		/* Single erase size */
546 		slave->mtd.erasesize = master->erasesize;
547 	}
548 
549 	if ((slave->mtd.flags & MTD_WRITEABLE) &&
550 	    mtd_mod_by_eb(slave->offset, &slave->mtd)) {
551 		/* Doesn't start on a boundary of major erase size */
552 		/* FIXME: Let it be writable if it is on a boundary of
553 		 * _minor_ erase size though */
554 		slave->mtd.flags &= ~MTD_WRITEABLE;
555 		printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
556 			part->name);
557 	}
558 	if ((slave->mtd.flags & MTD_WRITEABLE) &&
559 	    mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) {
560 		slave->mtd.flags &= ~MTD_WRITEABLE;
561 		printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
562 			part->name);
563 	}
564 
565 	slave->mtd.ecclayout = master->ecclayout;
566 	slave->mtd.ecc_step_size = master->ecc_step_size;
567 	slave->mtd.ecc_strength = master->ecc_strength;
568 	slave->mtd.bitflip_threshold = master->bitflip_threshold;
569 
570 	if (master->_block_isbad) {
571 		uint64_t offs = 0;
572 
573 		while (offs < slave->mtd.size) {
574 			if (mtd_block_isbad(master, offs + slave->offset))
575 				slave->mtd.ecc_stats.badblocks++;
576 			offs += slave->mtd.erasesize;
577 		}
578 	}
579 
580 out_register:
581 	return slave;
582 }
583 
584 #ifndef __UBOOT__
585 int mtd_add_partition(struct mtd_info *master, const char *name,
586 		      long long offset, long long length)
587 {
588 	struct mtd_partition part;
589 	struct mtd_part *p, *new;
590 	uint64_t start, end;
591 	int ret = 0;
592 
593 	/* the direct offset is expected */
594 	if (offset == MTDPART_OFS_APPEND ||
595 	    offset == MTDPART_OFS_NXTBLK)
596 		return -EINVAL;
597 
598 	if (length == MTDPART_SIZ_FULL)
599 		length = master->size - offset;
600 
601 	if (length <= 0)
602 		return -EINVAL;
603 
604 	part.name = name;
605 	part.size = length;
606 	part.offset = offset;
607 	part.mask_flags = 0;
608 	part.ecclayout = NULL;
609 
610 	new = allocate_partition(master, &part, -1, offset);
611 	if (IS_ERR(new))
612 		return PTR_ERR(new);
613 
614 	start = offset;
615 	end = offset + length;
616 
617 	mutex_lock(&mtd_partitions_mutex);
618 	list_for_each_entry(p, &mtd_partitions, list)
619 		if (p->master == master) {
620 			if ((start >= p->offset) &&
621 			    (start < (p->offset + p->mtd.size)))
622 				goto err_inv;
623 
624 			if ((end >= p->offset) &&
625 			    (end < (p->offset + p->mtd.size)))
626 				goto err_inv;
627 		}
628 
629 	list_add(&new->list, &mtd_partitions);
630 	mutex_unlock(&mtd_partitions_mutex);
631 
632 	add_mtd_device(&new->mtd);
633 
634 	return ret;
635 err_inv:
636 	mutex_unlock(&mtd_partitions_mutex);
637 	free_partition(new);
638 	return -EINVAL;
639 }
640 EXPORT_SYMBOL_GPL(mtd_add_partition);
641 
642 int mtd_del_partition(struct mtd_info *master, int partno)
643 {
644 	struct mtd_part *slave, *next;
645 	int ret = -EINVAL;
646 
647 	mutex_lock(&mtd_partitions_mutex);
648 	list_for_each_entry_safe(slave, next, &mtd_partitions, list)
649 		if ((slave->master == master) &&
650 		    (slave->mtd.index == partno)) {
651 			ret = del_mtd_device(&slave->mtd);
652 			if (ret < 0)
653 				break;
654 
655 			list_del(&slave->list);
656 			free_partition(slave);
657 			break;
658 		}
659 	mutex_unlock(&mtd_partitions_mutex);
660 
661 	return ret;
662 }
663 EXPORT_SYMBOL_GPL(mtd_del_partition);
664 #endif
665 
666 /*
667  * This function, given a master MTD object and a partition table, creates
668  * and registers slave MTD objects which are bound to the master according to
669  * the partition definitions.
670  *
671  * We don't register the master, or expect the caller to have done so,
672  * for reasons of data integrity.
673  */
674 
675 int add_mtd_partitions(struct mtd_info *master,
676 		       const struct mtd_partition *parts,
677 		       int nbparts)
678 {
679 	struct mtd_part *slave;
680 	uint64_t cur_offset = 0;
681 	int i;
682 
683 #ifdef __UBOOT__
684 	/*
685 	 * Need to init the list here, since LIST_INIT() does not
686 	 * work on platforms where relocation has problems (like MIPS
687 	 * & PPC).
688 	 */
689 	if (mtd_partitions.next == NULL)
690 		INIT_LIST_HEAD(&mtd_partitions);
691 #endif
692 
693 	debug("Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
694 
695 	for (i = 0; i < nbparts; i++) {
696 		slave = allocate_partition(master, parts + i, i, cur_offset);
697 		if (IS_ERR(slave))
698 			return PTR_ERR(slave);
699 
700 		mutex_lock(&mtd_partitions_mutex);
701 		list_add(&slave->list, &mtd_partitions);
702 		mutex_unlock(&mtd_partitions_mutex);
703 
704 		add_mtd_device(&slave->mtd);
705 
706 		cur_offset = slave->offset + slave->mtd.size;
707 	}
708 
709 	return 0;
710 }
711 
712 #ifndef __UBOOT__
713 static DEFINE_SPINLOCK(part_parser_lock);
714 static LIST_HEAD(part_parsers);
715 
716 static struct mtd_part_parser *get_partition_parser(const char *name)
717 {
718 	struct mtd_part_parser *p, *ret = NULL;
719 
720 	spin_lock(&part_parser_lock);
721 
722 	list_for_each_entry(p, &part_parsers, list)
723 		if (!strcmp(p->name, name) && try_module_get(p->owner)) {
724 			ret = p;
725 			break;
726 		}
727 
728 	spin_unlock(&part_parser_lock);
729 
730 	return ret;
731 }
732 
733 #define put_partition_parser(p) do { module_put((p)->owner); } while (0)
734 
735 void register_mtd_parser(struct mtd_part_parser *p)
736 {
737 	spin_lock(&part_parser_lock);
738 	list_add(&p->list, &part_parsers);
739 	spin_unlock(&part_parser_lock);
740 }
741 EXPORT_SYMBOL_GPL(register_mtd_parser);
742 
743 void deregister_mtd_parser(struct mtd_part_parser *p)
744 {
745 	spin_lock(&part_parser_lock);
746 	list_del(&p->list);
747 	spin_unlock(&part_parser_lock);
748 }
749 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
750 
751 /*
752  * Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
753  * are changing this array!
754  */
755 static const char * const default_mtd_part_types[] = {
756 	"cmdlinepart",
757 	"ofpart",
758 	NULL
759 };
760 
761 /**
762  * parse_mtd_partitions - parse MTD partitions
763  * @master: the master partition (describes whole MTD device)
764  * @types: names of partition parsers to try or %NULL
765  * @pparts: array of partitions found is returned here
766  * @data: MTD partition parser-specific data
767  *
768  * This function tries to find partition on MTD device @master. It uses MTD
769  * partition parsers, specified in @types. However, if @types is %NULL, then
770  * the default list of parsers is used. The default list contains only the
771  * "cmdlinepart" and "ofpart" parsers ATM.
772  * Note: If there are more then one parser in @types, the kernel only takes the
773  * partitions parsed out by the first parser.
774  *
775  * This function may return:
776  * o a negative error code in case of failure
777  * o zero if no partitions were found
778  * o a positive number of found partitions, in which case on exit @pparts will
779  *   point to an array containing this number of &struct mtd_info objects.
780  */
781 int parse_mtd_partitions(struct mtd_info *master, const char *const *types,
782 			 struct mtd_partition **pparts,
783 			 struct mtd_part_parser_data *data)
784 {
785 	struct mtd_part_parser *parser;
786 	int ret = 0;
787 
788 	if (!types)
789 		types = default_mtd_part_types;
790 
791 	for ( ; ret <= 0 && *types; types++) {
792 		parser = get_partition_parser(*types);
793 		if (!parser && !request_module("%s", *types))
794 			parser = get_partition_parser(*types);
795 		if (!parser)
796 			continue;
797 		ret = (*parser->parse_fn)(master, pparts, data);
798 		put_partition_parser(parser);
799 		if (ret > 0) {
800 			printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
801 			       ret, parser->name, master->name);
802 			break;
803 		}
804 	}
805 	return ret;
806 }
807 #endif
808 
809 int mtd_is_partition(const struct mtd_info *mtd)
810 {
811 	struct mtd_part *part;
812 	int ispart = 0;
813 
814 	mutex_lock(&mtd_partitions_mutex);
815 	list_for_each_entry(part, &mtd_partitions, list)
816 		if (&part->mtd == mtd) {
817 			ispart = 1;
818 			break;
819 		}
820 	mutex_unlock(&mtd_partitions_mutex);
821 
822 	return ispart;
823 }
824 EXPORT_SYMBOL_GPL(mtd_is_partition);
825 
826 /* Returns the size of the entire flash chip */
827 uint64_t mtd_get_device_size(const struct mtd_info *mtd)
828 {
829 	if (!mtd_is_partition(mtd))
830 		return mtd->size;
831 
832 	return PART(mtd)->master->size;
833 }
834 EXPORT_SYMBOL_GPL(mtd_get_device_size);
835