xref: /openbmc/u-boot/drivers/mtd/mtdpart.c (revision 2bae75a4)
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 #ifndef __UBOOT__
13 #include <linux/module.h>
14 #include <linux/types.h>
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/list.h>
18 #include <linux/kmod.h>
19 #endif
20 
21 #include <common.h>
22 #include <malloc.h>
23 #include <asm/errno.h>
24 #include <linux/compat.h>
25 #include <ubi_uboot.h>
26 
27 #include <linux/mtd/mtd.h>
28 #include <linux/mtd/partitions.h>
29 #include <linux/err.h>
30 
31 #include "mtdcore.h"
32 
33 /* Our partition linked list */
34 static LIST_HEAD(mtd_partitions);
35 #ifndef __UBOOT__
36 static DEFINE_MUTEX(mtd_partitions_mutex);
37 #else
38 DEFINE_MUTEX(mtd_partitions_mutex);
39 #endif
40 
41 /* Our partition node structure */
42 struct mtd_part {
43 	struct mtd_info mtd;
44 	struct mtd_info *master;
45 	uint64_t offset;
46 	struct list_head list;
47 };
48 
49 /*
50  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
51  * the pointer to that structure with this macro.
52  */
53 #define PART(x)  ((struct mtd_part *)(x))
54 
55 
56 #ifdef __UBOOT__
57 /* from mm/util.c */
58 
59 /**
60  * kstrdup - allocate space for and copy an existing string
61  * @s: the string to duplicate
62  * @gfp: the GFP mask used in the kmalloc() call when allocating memory
63  */
64 char *kstrdup(const char *s, gfp_t gfp)
65 {
66 	size_t len;
67 	char *buf;
68 
69 	if (!s)
70 		return NULL;
71 
72 	len = strlen(s) + 1;
73 	buf = kmalloc(len, gfp);
74 	if (buf)
75 		memcpy(buf, s, len);
76 	return buf;
77 }
78 #endif
79 
80 /*
81  * MTD methods which simply translate the effective address and pass through
82  * to the _real_ device.
83  */
84 
85 static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
86 		size_t *retlen, u_char *buf)
87 {
88 	struct mtd_part *part = PART(mtd);
89 	struct mtd_ecc_stats stats;
90 	int res;
91 
92 	stats = part->master->ecc_stats;
93 	res = part->master->_read(part->master, from + part->offset, len,
94 				  retlen, buf);
95 	if (unlikely(mtd_is_eccerr(res)))
96 		mtd->ecc_stats.failed +=
97 			part->master->ecc_stats.failed - stats.failed;
98 	else
99 		mtd->ecc_stats.corrected +=
100 			part->master->ecc_stats.corrected - stats.corrected;
101 	return res;
102 }
103 
104 #ifndef __UBOOT__
105 static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
106 		size_t *retlen, void **virt, resource_size_t *phys)
107 {
108 	struct mtd_part *part = PART(mtd);
109 
110 	return part->master->_point(part->master, from + part->offset, len,
111 				    retlen, virt, phys);
112 }
113 
114 static int part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
115 {
116 	struct mtd_part *part = PART(mtd);
117 
118 	return part->master->_unpoint(part->master, from + part->offset, len);
119 }
120 #endif
121 
122 static unsigned long part_get_unmapped_area(struct mtd_info *mtd,
123 					    unsigned long len,
124 					    unsigned long offset,
125 					    unsigned long flags)
126 {
127 	struct mtd_part *part = PART(mtd);
128 
129 	offset += part->offset;
130 	return part->master->_get_unmapped_area(part->master, len, offset,
131 						flags);
132 }
133 
134 static int part_read_oob(struct mtd_info *mtd, loff_t from,
135 		struct mtd_oob_ops *ops)
136 {
137 	struct mtd_part *part = PART(mtd);
138 	int res;
139 
140 	if (from >= mtd->size)
141 		return -EINVAL;
142 	if (ops->datbuf && from + ops->len > mtd->size)
143 		return -EINVAL;
144 
145 	/*
146 	 * If OOB is also requested, make sure that we do not read past the end
147 	 * of this partition.
148 	 */
149 	if (ops->oobbuf) {
150 		size_t len, pages;
151 
152 		if (ops->mode == MTD_OPS_AUTO_OOB)
153 			len = mtd->oobavail;
154 		else
155 			len = mtd->oobsize;
156 		pages = mtd_div_by_ws(mtd->size, mtd);
157 		pages -= mtd_div_by_ws(from, mtd);
158 		if (ops->ooboffs + ops->ooblen > pages * len)
159 			return -EINVAL;
160 	}
161 
162 	res = part->master->_read_oob(part->master, from + part->offset, ops);
163 	if (unlikely(res)) {
164 		if (mtd_is_bitflip(res))
165 			mtd->ecc_stats.corrected++;
166 		if (mtd_is_eccerr(res))
167 			mtd->ecc_stats.failed++;
168 	}
169 	return res;
170 }
171 
172 static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
173 		size_t len, size_t *retlen, u_char *buf)
174 {
175 	struct mtd_part *part = PART(mtd);
176 	return part->master->_read_user_prot_reg(part->master, from, len,
177 						 retlen, buf);
178 }
179 
180 static int part_get_user_prot_info(struct mtd_info *mtd, size_t len,
181 				   size_t *retlen, struct otp_info *buf)
182 {
183 	struct mtd_part *part = PART(mtd);
184 	return part->master->_get_user_prot_info(part->master, len, retlen,
185 						 buf);
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, size_t len,
197 				   size_t *retlen, struct otp_info *buf)
198 {
199 	struct mtd_part *part = PART(mtd);
200 	return part->master->_get_fact_prot_info(part->master, len, retlen,
201 						 buf);
202 }
203 
204 static int part_write(struct mtd_info *mtd, loff_t to, size_t len,
205 		size_t *retlen, const u_char *buf)
206 {
207 	struct mtd_part *part = PART(mtd);
208 	return part->master->_write(part->master, to + part->offset, len,
209 				    retlen, buf);
210 }
211 
212 static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
213 		size_t *retlen, const u_char *buf)
214 {
215 	struct mtd_part *part = PART(mtd);
216 	return part->master->_panic_write(part->master, to + part->offset, len,
217 					  retlen, buf);
218 }
219 
220 static int part_write_oob(struct mtd_info *mtd, loff_t to,
221 		struct mtd_oob_ops *ops)
222 {
223 	struct mtd_part *part = PART(mtd);
224 
225 	if (to >= mtd->size)
226 		return -EINVAL;
227 	if (ops->datbuf && to + ops->len > mtd->size)
228 		return -EINVAL;
229 	return part->master->_write_oob(part->master, to + part->offset, ops);
230 }
231 
232 static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
233 		size_t len, size_t *retlen, u_char *buf)
234 {
235 	struct mtd_part *part = PART(mtd);
236 	return part->master->_write_user_prot_reg(part->master, from, len,
237 						  retlen, buf);
238 }
239 
240 static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
241 		size_t len)
242 {
243 	struct mtd_part *part = PART(mtd);
244 	return part->master->_lock_user_prot_reg(part->master, from, len);
245 }
246 
247 #ifndef __UBOOT__
248 static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,
249 		unsigned long count, loff_t to, size_t *retlen)
250 {
251 	struct mtd_part *part = PART(mtd);
252 	return part->master->_writev(part->master, vecs, count,
253 				     to + part->offset, retlen);
254 }
255 #endif
256 
257 static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
258 {
259 	struct mtd_part *part = PART(mtd);
260 	int ret;
261 
262 	instr->addr += part->offset;
263 	ret = part->master->_erase(part->master, instr);
264 	if (ret) {
265 		if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
266 			instr->fail_addr -= part->offset;
267 		instr->addr -= part->offset;
268 	}
269 	return ret;
270 }
271 
272 void mtd_erase_callback(struct erase_info *instr)
273 {
274 	if (instr->mtd->_erase == part_erase) {
275 		struct mtd_part *part = PART(instr->mtd);
276 
277 		if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
278 			instr->fail_addr -= part->offset;
279 		instr->addr -= part->offset;
280 	}
281 	if (instr->callback)
282 		instr->callback(instr);
283 }
284 EXPORT_SYMBOL_GPL(mtd_erase_callback);
285 
286 static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
287 {
288 	struct mtd_part *part = PART(mtd);
289 	return part->master->_lock(part->master, ofs + part->offset, len);
290 }
291 
292 static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
293 {
294 	struct mtd_part *part = PART(mtd);
295 	return part->master->_unlock(part->master, ofs + part->offset, len);
296 }
297 
298 static int part_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
299 {
300 	struct mtd_part *part = PART(mtd);
301 	return part->master->_is_locked(part->master, ofs + part->offset, len);
302 }
303 
304 static void part_sync(struct mtd_info *mtd)
305 {
306 	struct mtd_part *part = PART(mtd);
307 	part->master->_sync(part->master);
308 }
309 
310 #ifndef __UBOOT__
311 static int part_suspend(struct mtd_info *mtd)
312 {
313 	struct mtd_part *part = PART(mtd);
314 	return part->master->_suspend(part->master);
315 }
316 
317 static void part_resume(struct mtd_info *mtd)
318 {
319 	struct mtd_part *part = PART(mtd);
320 	part->master->_resume(part->master);
321 }
322 #endif
323 
324 static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
325 {
326 	struct mtd_part *part = PART(mtd);
327 	ofs += part->offset;
328 	return part->master->_block_isbad(part->master, ofs);
329 }
330 
331 static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
332 {
333 	struct mtd_part *part = PART(mtd);
334 	int res;
335 
336 	ofs += part->offset;
337 	res = part->master->_block_markbad(part->master, ofs);
338 	if (!res)
339 		mtd->ecc_stats.badblocks++;
340 	return res;
341 }
342 
343 static inline void free_partition(struct mtd_part *p)
344 {
345 	kfree(p->mtd.name);
346 	kfree(p);
347 }
348 
349 /*
350  * This function unregisters and destroy all slave MTD objects which are
351  * attached to the given master MTD object.
352  */
353 
354 int del_mtd_partitions(struct mtd_info *master)
355 {
356 	struct mtd_part *slave, *next;
357 	int ret, err = 0;
358 
359 	mutex_lock(&mtd_partitions_mutex);
360 	list_for_each_entry_safe(slave, next, &mtd_partitions, list)
361 		if (slave->master == master) {
362 			ret = del_mtd_device(&slave->mtd);
363 			if (ret < 0) {
364 				err = ret;
365 				continue;
366 			}
367 			list_del(&slave->list);
368 			free_partition(slave);
369 		}
370 	mutex_unlock(&mtd_partitions_mutex);
371 
372 	return err;
373 }
374 
375 static struct mtd_part *allocate_partition(struct mtd_info *master,
376 			const struct mtd_partition *part, int partno,
377 			uint64_t cur_offset)
378 {
379 	struct mtd_part *slave;
380 	char *name;
381 
382 	/* allocate the partition structure */
383 	slave = kzalloc(sizeof(*slave), GFP_KERNEL);
384 	name = kstrdup(part->name, GFP_KERNEL);
385 	if (!name || !slave) {
386 		printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
387 		       master->name);
388 		kfree(name);
389 		kfree(slave);
390 		return ERR_PTR(-ENOMEM);
391 	}
392 
393 	/* set up the MTD object for this partition */
394 	slave->mtd.type = master->type;
395 	slave->mtd.flags = master->flags & ~part->mask_flags;
396 	slave->mtd.size = part->size;
397 	slave->mtd.writesize = master->writesize;
398 	slave->mtd.writebufsize = master->writebufsize;
399 	slave->mtd.oobsize = master->oobsize;
400 	slave->mtd.oobavail = master->oobavail;
401 	slave->mtd.subpage_sft = master->subpage_sft;
402 
403 	slave->mtd.name = name;
404 	slave->mtd.owner = master->owner;
405 #ifndef __UBOOT__
406 	slave->mtd.backing_dev_info = master->backing_dev_info;
407 
408 	/* NOTE:  we don't arrange MTDs as a tree; it'd be error-prone
409 	 * to have the same data be in two different partitions.
410 	 */
411 	slave->mtd.dev.parent = master->dev.parent;
412 #endif
413 
414 	slave->mtd._read = part_read;
415 	slave->mtd._write = part_write;
416 
417 	if (master->_panic_write)
418 		slave->mtd._panic_write = part_panic_write;
419 
420 #ifndef __UBOOT__
421 	if (master->_point && master->_unpoint) {
422 		slave->mtd._point = part_point;
423 		slave->mtd._unpoint = part_unpoint;
424 	}
425 #endif
426 
427 	if (master->_get_unmapped_area)
428 		slave->mtd._get_unmapped_area = part_get_unmapped_area;
429 	if (master->_read_oob)
430 		slave->mtd._read_oob = part_read_oob;
431 	if (master->_write_oob)
432 		slave->mtd._write_oob = part_write_oob;
433 	if (master->_read_user_prot_reg)
434 		slave->mtd._read_user_prot_reg = part_read_user_prot_reg;
435 	if (master->_read_fact_prot_reg)
436 		slave->mtd._read_fact_prot_reg = part_read_fact_prot_reg;
437 	if (master->_write_user_prot_reg)
438 		slave->mtd._write_user_prot_reg = part_write_user_prot_reg;
439 	if (master->_lock_user_prot_reg)
440 		slave->mtd._lock_user_prot_reg = part_lock_user_prot_reg;
441 	if (master->_get_user_prot_info)
442 		slave->mtd._get_user_prot_info = part_get_user_prot_info;
443 	if (master->_get_fact_prot_info)
444 		slave->mtd._get_fact_prot_info = part_get_fact_prot_info;
445 	if (master->_sync)
446 		slave->mtd._sync = part_sync;
447 #ifndef __UBOOT__
448 	if (!partno && !master->dev.class && master->_suspend &&
449 	    master->_resume) {
450 			slave->mtd._suspend = part_suspend;
451 			slave->mtd._resume = part_resume;
452 	}
453 	if (master->_writev)
454 		slave->mtd._writev = part_writev;
455 #endif
456 	if (master->_lock)
457 		slave->mtd._lock = part_lock;
458 	if (master->_unlock)
459 		slave->mtd._unlock = part_unlock;
460 	if (master->_is_locked)
461 		slave->mtd._is_locked = part_is_locked;
462 	if (master->_block_isbad)
463 		slave->mtd._block_isbad = part_block_isbad;
464 	if (master->_block_markbad)
465 		slave->mtd._block_markbad = part_block_markbad;
466 	slave->mtd._erase = part_erase;
467 	slave->master = master;
468 	slave->offset = part->offset;
469 
470 	if (slave->offset == MTDPART_OFS_APPEND)
471 		slave->offset = cur_offset;
472 	if (slave->offset == MTDPART_OFS_NXTBLK) {
473 		slave->offset = cur_offset;
474 		if (mtd_mod_by_eb(cur_offset, master) != 0) {
475 			/* Round up to next erasesize */
476 			slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
477 			debug("Moving partition %d: "
478 			       "0x%012llx -> 0x%012llx\n", partno,
479 			       (unsigned long long)cur_offset, (unsigned long long)slave->offset);
480 		}
481 	}
482 	if (slave->offset == MTDPART_OFS_RETAIN) {
483 		slave->offset = cur_offset;
484 		if (master->size - slave->offset >= slave->mtd.size) {
485 			slave->mtd.size = master->size - slave->offset
486 							- slave->mtd.size;
487 		} else {
488 			debug("mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n",
489 				part->name, master->size - slave->offset,
490 				slave->mtd.size);
491 			/* register to preserve ordering */
492 			goto out_register;
493 		}
494 	}
495 	if (slave->mtd.size == MTDPART_SIZ_FULL)
496 		slave->mtd.size = master->size - slave->offset;
497 
498 	debug("0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
499 		(unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
500 
501 	/* let's do some sanity checks */
502 	if (slave->offset >= master->size) {
503 		/* let's register it anyway to preserve ordering */
504 		slave->offset = 0;
505 		slave->mtd.size = 0;
506 		printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
507 			part->name);
508 		goto out_register;
509 	}
510 	if (slave->offset + slave->mtd.size > master->size) {
511 		slave->mtd.size = master->size - slave->offset;
512 		printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
513 			part->name, master->name, (unsigned long long)slave->mtd.size);
514 	}
515 	if (master->numeraseregions > 1) {
516 		/* Deal with variable erase size stuff */
517 		int i, max = master->numeraseregions;
518 		u64 end = slave->offset + slave->mtd.size;
519 		struct mtd_erase_region_info *regions = master->eraseregions;
520 
521 		/* Find the first erase regions which is part of this
522 		 * partition. */
523 		for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
524 			;
525 		/* The loop searched for the region _behind_ the first one */
526 		if (i > 0)
527 			i--;
528 
529 		/* Pick biggest erasesize */
530 		for (; i < max && regions[i].offset < end; i++) {
531 			if (slave->mtd.erasesize < regions[i].erasesize) {
532 				slave->mtd.erasesize = regions[i].erasesize;
533 			}
534 		}
535 		BUG_ON(slave->mtd.erasesize == 0);
536 	} else {
537 		/* Single erase size */
538 		slave->mtd.erasesize = master->erasesize;
539 	}
540 
541 	if ((slave->mtd.flags & MTD_WRITEABLE) &&
542 	    mtd_mod_by_eb(slave->offset, &slave->mtd)) {
543 		/* Doesn't start on a boundary of major erase size */
544 		/* FIXME: Let it be writable if it is on a boundary of
545 		 * _minor_ erase size though */
546 		slave->mtd.flags &= ~MTD_WRITEABLE;
547 		printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
548 			part->name);
549 	}
550 	if ((slave->mtd.flags & MTD_WRITEABLE) &&
551 	    mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) {
552 		slave->mtd.flags &= ~MTD_WRITEABLE;
553 		printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
554 			part->name);
555 	}
556 
557 	slave->mtd.ecclayout = master->ecclayout;
558 	slave->mtd.ecc_step_size = master->ecc_step_size;
559 	slave->mtd.ecc_strength = master->ecc_strength;
560 	slave->mtd.bitflip_threshold = master->bitflip_threshold;
561 
562 	if (master->_block_isbad) {
563 		uint64_t offs = 0;
564 
565 		while (offs < slave->mtd.size) {
566 			if (mtd_block_isbad(master, offs + slave->offset))
567 				slave->mtd.ecc_stats.badblocks++;
568 			offs += slave->mtd.erasesize;
569 		}
570 	}
571 
572 out_register:
573 	return slave;
574 }
575 
576 #ifndef __UBOOT__
577 int mtd_add_partition(struct mtd_info *master, const char *name,
578 		      long long offset, long long length)
579 {
580 	struct mtd_partition part;
581 	struct mtd_part *p, *new;
582 	uint64_t start, end;
583 	int ret = 0;
584 
585 	/* the direct offset is expected */
586 	if (offset == MTDPART_OFS_APPEND ||
587 	    offset == MTDPART_OFS_NXTBLK)
588 		return -EINVAL;
589 
590 	if (length == MTDPART_SIZ_FULL)
591 		length = master->size - offset;
592 
593 	if (length <= 0)
594 		return -EINVAL;
595 
596 	part.name = name;
597 	part.size = length;
598 	part.offset = offset;
599 	part.mask_flags = 0;
600 	part.ecclayout = NULL;
601 
602 	new = allocate_partition(master, &part, -1, offset);
603 	if (IS_ERR(new))
604 		return PTR_ERR(new);
605 
606 	start = offset;
607 	end = offset + length;
608 
609 	mutex_lock(&mtd_partitions_mutex);
610 	list_for_each_entry(p, &mtd_partitions, list)
611 		if (p->master == master) {
612 			if ((start >= p->offset) &&
613 			    (start < (p->offset + p->mtd.size)))
614 				goto err_inv;
615 
616 			if ((end >= p->offset) &&
617 			    (end < (p->offset + p->mtd.size)))
618 				goto err_inv;
619 		}
620 
621 	list_add(&new->list, &mtd_partitions);
622 	mutex_unlock(&mtd_partitions_mutex);
623 
624 	add_mtd_device(&new->mtd);
625 
626 	return ret;
627 err_inv:
628 	mutex_unlock(&mtd_partitions_mutex);
629 	free_partition(new);
630 	return -EINVAL;
631 }
632 EXPORT_SYMBOL_GPL(mtd_add_partition);
633 
634 int mtd_del_partition(struct mtd_info *master, int partno)
635 {
636 	struct mtd_part *slave, *next;
637 	int ret = -EINVAL;
638 
639 	mutex_lock(&mtd_partitions_mutex);
640 	list_for_each_entry_safe(slave, next, &mtd_partitions, list)
641 		if ((slave->master == master) &&
642 		    (slave->mtd.index == partno)) {
643 			ret = del_mtd_device(&slave->mtd);
644 			if (ret < 0)
645 				break;
646 
647 			list_del(&slave->list);
648 			free_partition(slave);
649 			break;
650 		}
651 	mutex_unlock(&mtd_partitions_mutex);
652 
653 	return ret;
654 }
655 EXPORT_SYMBOL_GPL(mtd_del_partition);
656 #endif
657 
658 /*
659  * This function, given a master MTD object and a partition table, creates
660  * and registers slave MTD objects which are bound to the master according to
661  * the partition definitions.
662  *
663  * We don't register the master, or expect the caller to have done so,
664  * for reasons of data integrity.
665  */
666 
667 int add_mtd_partitions(struct mtd_info *master,
668 		       const struct mtd_partition *parts,
669 		       int nbparts)
670 {
671 	struct mtd_part *slave;
672 	uint64_t cur_offset = 0;
673 	int i;
674 
675 #ifdef __UBOOT__
676 	/*
677 	 * Need to init the list here, since LIST_INIT() does not
678 	 * work on platforms where relocation has problems (like MIPS
679 	 * & PPC).
680 	 */
681 	if (mtd_partitions.next == NULL)
682 		INIT_LIST_HEAD(&mtd_partitions);
683 #endif
684 
685 	debug("Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
686 
687 	for (i = 0; i < nbparts; i++) {
688 		slave = allocate_partition(master, parts + i, i, cur_offset);
689 		if (IS_ERR(slave))
690 			return PTR_ERR(slave);
691 
692 		mutex_lock(&mtd_partitions_mutex);
693 		list_add(&slave->list, &mtd_partitions);
694 		mutex_unlock(&mtd_partitions_mutex);
695 
696 		add_mtd_device(&slave->mtd);
697 
698 		cur_offset = slave->offset + slave->mtd.size;
699 	}
700 
701 	return 0;
702 }
703 
704 #ifndef __UBOOT__
705 static DEFINE_SPINLOCK(part_parser_lock);
706 static LIST_HEAD(part_parsers);
707 
708 static struct mtd_part_parser *get_partition_parser(const char *name)
709 {
710 	struct mtd_part_parser *p, *ret = NULL;
711 
712 	spin_lock(&part_parser_lock);
713 
714 	list_for_each_entry(p, &part_parsers, list)
715 		if (!strcmp(p->name, name) && try_module_get(p->owner)) {
716 			ret = p;
717 			break;
718 		}
719 
720 	spin_unlock(&part_parser_lock);
721 
722 	return ret;
723 }
724 
725 #define put_partition_parser(p) do { module_put((p)->owner); } while (0)
726 
727 void register_mtd_parser(struct mtd_part_parser *p)
728 {
729 	spin_lock(&part_parser_lock);
730 	list_add(&p->list, &part_parsers);
731 	spin_unlock(&part_parser_lock);
732 }
733 EXPORT_SYMBOL_GPL(register_mtd_parser);
734 
735 void deregister_mtd_parser(struct mtd_part_parser *p)
736 {
737 	spin_lock(&part_parser_lock);
738 	list_del(&p->list);
739 	spin_unlock(&part_parser_lock);
740 }
741 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
742 
743 /*
744  * Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
745  * are changing this array!
746  */
747 static const char * const default_mtd_part_types[] = {
748 	"cmdlinepart",
749 	"ofpart",
750 	NULL
751 };
752 
753 /**
754  * parse_mtd_partitions - parse MTD partitions
755  * @master: the master partition (describes whole MTD device)
756  * @types: names of partition parsers to try or %NULL
757  * @pparts: array of partitions found is returned here
758  * @data: MTD partition parser-specific data
759  *
760  * This function tries to find partition on MTD device @master. It uses MTD
761  * partition parsers, specified in @types. However, if @types is %NULL, then
762  * the default list of parsers is used. The default list contains only the
763  * "cmdlinepart" and "ofpart" parsers ATM.
764  * Note: If there are more then one parser in @types, the kernel only takes the
765  * partitions parsed out by the first parser.
766  *
767  * This function may return:
768  * o a negative error code in case of failure
769  * o zero if no partitions were found
770  * o a positive number of found partitions, in which case on exit @pparts will
771  *   point to an array containing this number of &struct mtd_info objects.
772  */
773 int parse_mtd_partitions(struct mtd_info *master, const char *const *types,
774 			 struct mtd_partition **pparts,
775 			 struct mtd_part_parser_data *data)
776 {
777 	struct mtd_part_parser *parser;
778 	int ret = 0;
779 
780 	if (!types)
781 		types = default_mtd_part_types;
782 
783 	for ( ; ret <= 0 && *types; types++) {
784 		parser = get_partition_parser(*types);
785 		if (!parser && !request_module("%s", *types))
786 			parser = get_partition_parser(*types);
787 		if (!parser)
788 			continue;
789 		ret = (*parser->parse_fn)(master, pparts, data);
790 		put_partition_parser(parser);
791 		if (ret > 0) {
792 			printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
793 			       ret, parser->name, master->name);
794 			break;
795 		}
796 	}
797 	return ret;
798 }
799 #endif
800 
801 int mtd_is_partition(const struct mtd_info *mtd)
802 {
803 	struct mtd_part *part;
804 	int ispart = 0;
805 
806 	mutex_lock(&mtd_partitions_mutex);
807 	list_for_each_entry(part, &mtd_partitions, list)
808 		if (&part->mtd == mtd) {
809 			ispart = 1;
810 			break;
811 		}
812 	mutex_unlock(&mtd_partitions_mutex);
813 
814 	return ispart;
815 }
816 EXPORT_SYMBOL_GPL(mtd_is_partition);
817 
818 /* Returns the size of the entire flash chip */
819 uint64_t mtd_get_device_size(const struct mtd_info *mtd)
820 {
821 	if (!mtd_is_partition(mtd))
822 		return mtd->size;
823 
824 	return PART(mtd)->master->size;
825 }
826 EXPORT_SYMBOL_GPL(mtd_get_device_size);
827