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1// SPDX-License-Identifier: GPL-2.0-or-later
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#include <linux/module.h>
11#include <linux/types.h>
12#include <linux/kernel.h>
13#include <linux/slab.h>
14#include <linux/list.h>
15#include <linux/kmod.h>
16#include <linux/mtd/mtd.h>
17#include <linux/mtd/partitions.h>
18#include <linux/err.h>
19#include <linux/of.h>
20#include <linux/of_platform.h>
21
22#include "mtdcore.h"
23
24/*
25 * MTD methods which simply translate the effective address and pass through
26 * to the _real_ device.
27 */
28
29static inline void free_partition(struct mtd_info *mtd)
30{
31 kfree(mtd->name);
32 kfree(mtd);
33}
34
35void release_mtd_partition(struct mtd_info *mtd)
36{
37 WARN_ON(!list_empty(&mtd->part.node));
38 free_partition(mtd);
39}
40
41static struct mtd_info *allocate_partition(struct mtd_info *parent,
42 const struct mtd_partition *part,
43 int partno, uint64_t cur_offset)
44{
45 struct mtd_info *master = mtd_get_master(parent);
46 int wr_alignment = (parent->flags & MTD_NO_ERASE) ?
47 master->writesize : master->erasesize;
48 u64 parent_size = mtd_is_partition(parent) ?
49 parent->part.size : parent->size;
50 struct mtd_info *child;
51 u32 remainder;
52 char *name;
53 u64 tmp;
54
55 /* allocate the partition structure */
56 child = kzalloc(sizeof(*child), GFP_KERNEL);
57 name = kstrdup(part->name, GFP_KERNEL);
58 if (!name || !child) {
59 printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
60 parent->name);
61 kfree(name);
62 kfree(child);
63 return ERR_PTR(-ENOMEM);
64 }
65
66 /* set up the MTD object for this partition */
67 child->type = parent->type;
68 child->part.flags = parent->flags & ~part->mask_flags;
69 child->part.flags |= part->add_flags;
70 child->flags = child->part.flags;
71 child->part.size = part->size;
72 child->writesize = parent->writesize;
73 child->writebufsize = parent->writebufsize;
74 child->oobsize = parent->oobsize;
75 child->oobavail = parent->oobavail;
76 child->subpage_sft = parent->subpage_sft;
77
78 child->name = name;
79 child->owner = parent->owner;
80
81 /* NOTE: Historically, we didn't arrange MTDs as a tree out of
82 * concern for showing the same data in multiple partitions.
83 * However, it is very useful to have the master node present,
84 * so the MTD_PARTITIONED_MASTER option allows that. The master
85 * will have device nodes etc only if this is set, so make the
86 * parent conditional on that option. Note, this is a way to
87 * distinguish between the parent and its partitions in sysfs.
88 */
89 child->dev.parent = IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) || mtd_is_partition(parent) ?
90 &parent->dev : parent->dev.parent;
91 child->dev.of_node = part->of_node;
92 child->parent = parent;
93 child->part.offset = part->offset;
94 INIT_LIST_HEAD(&child->partitions);
95
96 if (child->part.offset == MTDPART_OFS_APPEND)
97 child->part.offset = cur_offset;
98 if (child->part.offset == MTDPART_OFS_NXTBLK) {
99 tmp = cur_offset;
100 child->part.offset = cur_offset;
101 remainder = do_div(tmp, wr_alignment);
102 if (remainder) {
103 child->part.offset += wr_alignment - remainder;
104 printk(KERN_NOTICE "Moving partition %d: "
105 "0x%012llx -> 0x%012llx\n", partno,
106 (unsigned long long)cur_offset,
107 child->part.offset);
108 }
109 }
110 if (child->part.offset == MTDPART_OFS_RETAIN) {
111 child->part.offset = cur_offset;
112 if (parent_size - child->part.offset >= child->part.size) {
113 child->part.size = parent_size - child->part.offset -
114 child->part.size;
115 } else {
116 printk(KERN_ERR "mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n",
117 part->name, parent_size - child->part.offset,
118 child->part.size);
119 /* register to preserve ordering */
120 goto out_register;
121 }
122 }
123 if (child->part.size == MTDPART_SIZ_FULL)
124 child->part.size = parent_size - child->part.offset;
125
126 printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n",
127 child->part.offset, child->part.offset + child->part.size,
128 child->name);
129
130 /* let's do some sanity checks */
131 if (child->part.offset >= parent_size) {
132 /* let's register it anyway to preserve ordering */
133 child->part.offset = 0;
134 child->part.size = 0;
135
136 /* Initialize ->erasesize to make add_mtd_device() happy. */
137 child->erasesize = parent->erasesize;
138 printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
139 part->name);
140 goto out_register;
141 }
142 if (child->part.offset + child->part.size > parent->size) {
143 child->part.size = parent_size - child->part.offset;
144 printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
145 part->name, parent->name, child->part.size);
146 }
147
148 if (parent->numeraseregions > 1) {
149 /* Deal with variable erase size stuff */
150 int i, max = parent->numeraseregions;
151 u64 end = child->part.offset + child->part.size;
152 struct mtd_erase_region_info *regions = parent->eraseregions;
153
154 /* Find the first erase regions which is part of this
155 * partition. */
156 for (i = 0; i < max && regions[i].offset <= child->part.offset;
157 i++)
158 ;
159 /* The loop searched for the region _behind_ the first one */
160 if (i > 0)
161 i--;
162
163 /* Pick biggest erasesize */
164 for (; i < max && regions[i].offset < end; i++) {
165 if (child->erasesize < regions[i].erasesize)
166 child->erasesize = regions[i].erasesize;
167 }
168 BUG_ON(child->erasesize == 0);
169 } else {
170 /* Single erase size */
171 child->erasesize = master->erasesize;
172 }
173
174 /*
175 * Child erasesize might differ from the parent one if the parent
176 * exposes several regions with different erasesize. Adjust
177 * wr_alignment accordingly.
178 */
179 if (!(child->flags & MTD_NO_ERASE))
180 wr_alignment = child->erasesize;
181
182 tmp = mtd_get_master_ofs(child, 0);
183 remainder = do_div(tmp, wr_alignment);
184 if ((child->flags & MTD_WRITEABLE) && remainder) {
185 /* Doesn't start on a boundary of major erase size */
186 /* FIXME: Let it be writable if it is on a boundary of
187 * _minor_ erase size though */
188 child->flags &= ~MTD_WRITEABLE;
189 printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase/write block boundary -- force read-only\n",
190 part->name);
191 }
192
193 tmp = mtd_get_master_ofs(child, 0) + child->part.size;
194 remainder = do_div(tmp, wr_alignment);
195 if ((child->flags & MTD_WRITEABLE) && remainder) {
196 child->flags &= ~MTD_WRITEABLE;
197 printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase/write block -- force read-only\n",
198 part->name);
199 }
200
201 child->size = child->part.size;
202 child->ecc_step_size = parent->ecc_step_size;
203 child->ecc_strength = parent->ecc_strength;
204 child->bitflip_threshold = parent->bitflip_threshold;
205
206 if (master->_block_isbad) {
207 uint64_t offs = 0;
208
209 while (offs < child->part.size) {
210 if (mtd_block_isreserved(child, offs))
211 child->ecc_stats.bbtblocks++;
212 else if (mtd_block_isbad(child, offs))
213 child->ecc_stats.badblocks++;
214 offs += child->erasesize;
215 }
216 }
217
218out_register:
219 return child;
220}
221
222static ssize_t offset_show(struct device *dev,
223 struct device_attribute *attr, char *buf)
224{
225 struct mtd_info *mtd = dev_get_drvdata(dev);
226
227 return sysfs_emit(buf, "%lld\n", mtd->part.offset);
228}
229static DEVICE_ATTR_RO(offset); /* mtd partition offset */
230
231static const struct attribute *mtd_partition_attrs[] = {
232 &dev_attr_offset.attr,
233 NULL
234};
235
236static int mtd_add_partition_attrs(struct mtd_info *new)
237{
238 int ret = sysfs_create_files(&new->dev.kobj, mtd_partition_attrs);
239 if (ret)
240 printk(KERN_WARNING
241 "mtd: failed to create partition attrs, err=%d\n", ret);
242 return ret;
243}
244
245int mtd_add_partition(struct mtd_info *parent, const char *name,
246 long long offset, long long length)
247{
248 struct mtd_info *master = mtd_get_master(parent);
249 u64 parent_size = mtd_is_partition(parent) ?
250 parent->part.size : parent->size;
251 struct mtd_partition part;
252 struct mtd_info *child;
253 int ret = 0;
254
255 /* the direct offset is expected */
256 if (offset == MTDPART_OFS_APPEND ||
257 offset == MTDPART_OFS_NXTBLK)
258 return -EINVAL;
259
260 if (length == MTDPART_SIZ_FULL)
261 length = parent_size - offset;
262
263 if (length <= 0)
264 return -EINVAL;
265
266 memset(&part, 0, sizeof(part));
267 part.name = name;
268 part.size = length;
269 part.offset = offset;
270
271 child = allocate_partition(parent, &part, -1, offset);
272 if (IS_ERR(child))
273 return PTR_ERR(child);
274
275 mutex_lock(&master->master.partitions_lock);
276 list_add_tail(&child->part.node, &parent->partitions);
277 mutex_unlock(&master->master.partitions_lock);
278
279 ret = add_mtd_device(child);
280 if (ret)
281 goto err_remove_part;
282
283 mtd_add_partition_attrs(child);
284
285 return 0;
286
287err_remove_part:
288 mutex_lock(&master->master.partitions_lock);
289 list_del(&child->part.node);
290 mutex_unlock(&master->master.partitions_lock);
291
292 free_partition(child);
293
294 return ret;
295}
296EXPORT_SYMBOL_GPL(mtd_add_partition);
297
298/**
299 * __mtd_del_partition - delete MTD partition
300 *
301 * @mtd: MTD structure to be deleted
302 *
303 * This function must be called with the partitions mutex locked.
304 */
305static int __mtd_del_partition(struct mtd_info *mtd)
306{
307 struct mtd_info *child, *next;
308 int err;
309
310 list_for_each_entry_safe(child, next, &mtd->partitions, part.node) {
311 err = __mtd_del_partition(child);
312 if (err)
313 return err;
314 }
315
316 sysfs_remove_files(&mtd->dev.kobj, mtd_partition_attrs);
317
318 list_del_init(&mtd->part.node);
319 err = del_mtd_device(mtd);
320 if (err)
321 return err;
322
323 return 0;
324}
325
326/*
327 * This function unregisters and destroy all slave MTD objects which are
328 * attached to the given MTD object, recursively.
329 */
330static int __del_mtd_partitions(struct mtd_info *mtd)
331{
332 struct mtd_info *child, *next;
333 int ret, err = 0;
334
335 list_for_each_entry_safe(child, next, &mtd->partitions, part.node) {
336 if (mtd_has_partitions(child))
337 __del_mtd_partitions(child);
338
339 pr_info("Deleting %s MTD partition\n", child->name);
340 list_del_init(&child->part.node);
341 ret = del_mtd_device(child);
342 if (ret < 0) {
343 pr_err("Error when deleting partition \"%s\" (%d)\n",
344 child->name, ret);
345 err = ret;
346 continue;
347 }
348 }
349
350 return err;
351}
352
353int del_mtd_partitions(struct mtd_info *mtd)
354{
355 struct mtd_info *master = mtd_get_master(mtd);
356 int ret;
357
358 pr_info("Deleting MTD partitions on \"%s\":\n", mtd->name);
359
360 mutex_lock(&master->master.partitions_lock);
361 ret = __del_mtd_partitions(mtd);
362 mutex_unlock(&master->master.partitions_lock);
363
364 return ret;
365}
366
367int mtd_del_partition(struct mtd_info *mtd, int partno)
368{
369 struct mtd_info *child, *master = mtd_get_master(mtd);
370 int ret = -EINVAL;
371
372 mutex_lock(&master->master.partitions_lock);
373 list_for_each_entry(child, &mtd->partitions, part.node) {
374 if (child->index == partno) {
375 ret = __mtd_del_partition(child);
376 break;
377 }
378 }
379 mutex_unlock(&master->master.partitions_lock);
380
381 return ret;
382}
383EXPORT_SYMBOL_GPL(mtd_del_partition);
384
385/*
386 * This function, given a parent MTD object and a partition table, creates
387 * and registers the child MTD objects which are bound to the parent according
388 * to the partition definitions.
389 *
390 * For historical reasons, this function's caller only registers the parent
391 * if the MTD_PARTITIONED_MASTER config option is set.
392 */
393
394int add_mtd_partitions(struct mtd_info *parent,
395 const struct mtd_partition *parts,
396 int nbparts)
397{
398 struct mtd_info *child, *master = mtd_get_master(parent);
399 uint64_t cur_offset = 0;
400 int i, ret;
401
402 printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n",
403 nbparts, parent->name);
404
405 for (i = 0; i < nbparts; i++) {
406 child = allocate_partition(parent, parts + i, i, cur_offset);
407 if (IS_ERR(child)) {
408 ret = PTR_ERR(child);
409 goto err_del_partitions;
410 }
411
412 mutex_lock(&master->master.partitions_lock);
413 list_add_tail(&child->part.node, &parent->partitions);
414 mutex_unlock(&master->master.partitions_lock);
415
416 ret = add_mtd_device(child);
417 if (ret) {
418 mutex_lock(&master->master.partitions_lock);
419 list_del(&child->part.node);
420 mutex_unlock(&master->master.partitions_lock);
421
422 free_partition(child);
423 goto err_del_partitions;
424 }
425
426 mtd_add_partition_attrs(child);
427
428 /* Look for subpartitions */
429 ret = parse_mtd_partitions(child, parts[i].types, NULL);
430 if (ret < 0) {
431 pr_err("Failed to parse subpartitions: %d\n", ret);
432 goto err_del_partitions;
433 }
434
435 cur_offset = child->part.offset + child->part.size;
436 }
437
438 return 0;
439
440err_del_partitions:
441 del_mtd_partitions(master);
442
443 return ret;
444}
445
446static DEFINE_SPINLOCK(part_parser_lock);
447static LIST_HEAD(part_parsers);
448
449static struct mtd_part_parser *mtd_part_parser_get(const char *name)
450{
451 struct mtd_part_parser *p, *ret = NULL;
452
453 spin_lock(&part_parser_lock);
454
455 list_for_each_entry(p, &part_parsers, list)
456 if (!strcmp(p->name, name) && try_module_get(p->owner)) {
457 ret = p;
458 break;
459 }
460
461 spin_unlock(&part_parser_lock);
462
463 return ret;
464}
465
466static inline void mtd_part_parser_put(const struct mtd_part_parser *p)
467{
468 module_put(p->owner);
469}
470
471/*
472 * Many partition parsers just expected the core to kfree() all their data in
473 * one chunk. Do that by default.
474 */
475static void mtd_part_parser_cleanup_default(const struct mtd_partition *pparts,
476 int nr_parts)
477{
478 kfree(pparts);
479}
480
481int __register_mtd_parser(struct mtd_part_parser *p, struct module *owner)
482{
483 p->owner = owner;
484
485 if (!p->cleanup)
486 p->cleanup = &mtd_part_parser_cleanup_default;
487
488 spin_lock(&part_parser_lock);
489 list_add(&p->list, &part_parsers);
490 spin_unlock(&part_parser_lock);
491
492 return 0;
493}
494EXPORT_SYMBOL_GPL(__register_mtd_parser);
495
496void deregister_mtd_parser(struct mtd_part_parser *p)
497{
498 spin_lock(&part_parser_lock);
499 list_del(&p->list);
500 spin_unlock(&part_parser_lock);
501}
502EXPORT_SYMBOL_GPL(deregister_mtd_parser);
503
504/*
505 * Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
506 * are changing this array!
507 */
508static const char * const default_mtd_part_types[] = {
509 "cmdlinepart",
510 "ofpart",
511 NULL
512};
513
514/* Check DT only when looking for subpartitions. */
515static const char * const default_subpartition_types[] = {
516 "ofpart",
517 NULL
518};
519
520static int mtd_part_do_parse(struct mtd_part_parser *parser,
521 struct mtd_info *master,
522 struct mtd_partitions *pparts,
523 struct mtd_part_parser_data *data)
524{
525 int ret;
526
527 ret = (*parser->parse_fn)(master, &pparts->parts, data);
528 pr_debug("%s: parser %s: %i\n", master->name, parser->name, ret);
529 if (ret <= 0)
530 return ret;
531
532 pr_notice("%d %s partitions found on MTD device %s\n", ret,
533 parser->name, master->name);
534
535 pparts->nr_parts = ret;
536 pparts->parser = parser;
537
538 return ret;
539}
540
541/**
542 * mtd_part_get_compatible_parser - find MTD parser by a compatible string
543 *
544 * @compat: compatible string describing partitions in a device tree
545 *
546 * MTD parsers can specify supported partitions by providing a table of
547 * compatibility strings. This function finds a parser that advertises support
548 * for a passed value of "compatible".
549 */
550static struct mtd_part_parser *mtd_part_get_compatible_parser(const char *compat)
551{
552 struct mtd_part_parser *p, *ret = NULL;
553
554 spin_lock(&part_parser_lock);
555
556 list_for_each_entry(p, &part_parsers, list) {
557 const struct of_device_id *matches;
558
559 matches = p->of_match_table;
560 if (!matches)
561 continue;
562
563 for (; matches->compatible[0]; matches++) {
564 if (!strcmp(matches->compatible, compat) &&
565 try_module_get(p->owner)) {
566 ret = p;
567 break;
568 }
569 }
570
571 if (ret)
572 break;
573 }
574
575 spin_unlock(&part_parser_lock);
576
577 return ret;
578}
579
580static int mtd_part_of_parse(struct mtd_info *master,
581 struct mtd_partitions *pparts)
582{
583 struct mtd_part_parser *parser;
584 struct device_node *np;
585 struct device_node *child;
586 struct property *prop;
587 struct device *dev;
588 const char *compat;
589 const char *fixed = "fixed-partitions";
590 int ret, err = 0;
591
592 dev = &master->dev;
593 /* Use parent device (controller) if the top level MTD is not registered */
594 if (!IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) && !mtd_is_partition(master))
595 dev = master->dev.parent;
596
597 np = mtd_get_of_node(master);
598 if (mtd_is_partition(master))
599 of_node_get(np);
600 else
601 np = of_get_child_by_name(np, "partitions");
602
603 /*
604 * Don't create devices that are added to a bus but will never get
605 * probed. That'll cause fw_devlink to block probing of consumers of
606 * this partition until the partition device is probed.
607 */
608 for_each_child_of_node(np, child)
609 if (of_device_is_compatible(child, "nvmem-cells"))
610 of_node_set_flag(child, OF_POPULATED);
611
612 of_property_for_each_string(np, "compatible", prop, compat) {
613 parser = mtd_part_get_compatible_parser(compat);
614 if (!parser)
615 continue;
616 ret = mtd_part_do_parse(parser, master, pparts, NULL);
617 if (ret > 0) {
618 of_platform_populate(np, NULL, NULL, dev);
619 of_node_put(np);
620 return ret;
621 }
622 mtd_part_parser_put(parser);
623 if (ret < 0 && !err)
624 err = ret;
625 }
626 of_platform_populate(np, NULL, NULL, dev);
627 of_node_put(np);
628
629 /*
630 * For backward compatibility we have to try the "fixed-partitions"
631 * parser. It supports old DT format with partitions specified as a
632 * direct subnodes of a flash device DT node without any compatibility
633 * specified we could match.
634 */
635 parser = mtd_part_parser_get(fixed);
636 if (!parser && !request_module("%s", fixed))
637 parser = mtd_part_parser_get(fixed);
638 if (parser) {
639 ret = mtd_part_do_parse(parser, master, pparts, NULL);
640 if (ret > 0)
641 return ret;
642 mtd_part_parser_put(parser);
643 if (ret < 0 && !err)
644 err = ret;
645 }
646
647 return err;
648}
649
650/**
651 * parse_mtd_partitions - parse and register MTD partitions
652 *
653 * @master: the master partition (describes whole MTD device)
654 * @types: names of partition parsers to try or %NULL
655 * @data: MTD partition parser-specific data
656 *
657 * This function tries to find & register partitions on MTD device @master. It
658 * uses MTD partition parsers, specified in @types. However, if @types is %NULL,
659 * then the default list of parsers is used. The default list contains only the
660 * "cmdlinepart" and "ofpart" parsers ATM.
661 * Note: If there are more then one parser in @types, the kernel only takes the
662 * partitions parsed out by the first parser.
663 *
664 * This function may return:
665 * o a negative error code in case of failure
666 * o number of found partitions otherwise
667 */
668int parse_mtd_partitions(struct mtd_info *master, const char *const *types,
669 struct mtd_part_parser_data *data)
670{
671 struct mtd_partitions pparts = { };
672 struct mtd_part_parser *parser;
673 int ret, err = 0;
674
675 if (!types)
676 types = mtd_is_partition(master) ? default_subpartition_types :
677 default_mtd_part_types;
678
679 for ( ; *types; types++) {
680 /*
681 * ofpart is a special type that means OF partitioning info
682 * should be used. It requires a bit different logic so it is
683 * handled in a separated function.
684 */
685 if (!strcmp(*types, "ofpart")) {
686 ret = mtd_part_of_parse(master, &pparts);
687 } else {
688 pr_debug("%s: parsing partitions %s\n", master->name,
689 *types);
690 parser = mtd_part_parser_get(*types);
691 if (!parser && !request_module("%s", *types))
692 parser = mtd_part_parser_get(*types);
693 pr_debug("%s: got parser %s\n", master->name,
694 parser ? parser->name : NULL);
695 if (!parser)
696 continue;
697 ret = mtd_part_do_parse(parser, master, &pparts, data);
698 if (ret <= 0)
699 mtd_part_parser_put(parser);
700 }
701 /* Found partitions! */
702 if (ret > 0) {
703 err = add_mtd_partitions(master, pparts.parts,
704 pparts.nr_parts);
705 mtd_part_parser_cleanup(&pparts);
706 return err ? err : pparts.nr_parts;
707 }
708 /*
709 * Stash the first error we see; only report it if no parser
710 * succeeds
711 */
712 if (ret < 0 && !err)
713 err = ret;
714 }
715 return err;
716}
717
718void mtd_part_parser_cleanup(struct mtd_partitions *parts)
719{
720 const struct mtd_part_parser *parser;
721
722 if (!parts)
723 return;
724
725 parser = parts->parser;
726 if (parser) {
727 if (parser->cleanup)
728 parser->cleanup(parts->parts, parts->nr_parts);
729
730 mtd_part_parser_put(parser);
731 }
732}
733
734/* Returns the size of the entire flash chip */
735uint64_t mtd_get_device_size(const struct mtd_info *mtd)
736{
737 struct mtd_info *master = mtd_get_master((struct mtd_info *)mtd);
738
739 return master->size;
740}
741EXPORT_SYMBOL_GPL(mtd_get_device_size);
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#include <linux/of.h>
34
35#include "mtdcore.h"
36
37/* Our partition linked list */
38static LIST_HEAD(mtd_partitions);
39static DEFINE_MUTEX(mtd_partitions_mutex);
40
41/**
42 * struct mtd_part - our partition node structure
43 *
44 * @mtd: struct holding partition details
45 * @parent: parent mtd - flash device or another partition
46 * @offset: partition offset relative to the *flash device*
47 */
48struct mtd_part {
49 struct mtd_info mtd;
50 struct mtd_info *parent;
51 uint64_t offset;
52 struct list_head list;
53};
54
55/*
56 * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
57 * the pointer to that structure.
58 */
59static inline struct mtd_part *mtd_to_part(const struct mtd_info *mtd)
60{
61 return container_of(mtd, struct mtd_part, mtd);
62}
63
64
65/*
66 * MTD methods which simply translate the effective address and pass through
67 * to the _real_ device.
68 */
69
70static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
71 size_t *retlen, u_char *buf)
72{
73 struct mtd_part *part = mtd_to_part(mtd);
74 struct mtd_ecc_stats stats;
75 int res;
76
77 stats = part->parent->ecc_stats;
78 res = part->parent->_read(part->parent, from + part->offset, len,
79 retlen, buf);
80 if (unlikely(mtd_is_eccerr(res)))
81 mtd->ecc_stats.failed +=
82 part->parent->ecc_stats.failed - stats.failed;
83 else
84 mtd->ecc_stats.corrected +=
85 part->parent->ecc_stats.corrected - stats.corrected;
86 return res;
87}
88
89static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
90 size_t *retlen, void **virt, resource_size_t *phys)
91{
92 struct mtd_part *part = mtd_to_part(mtd);
93
94 return part->parent->_point(part->parent, from + part->offset, len,
95 retlen, virt, phys);
96}
97
98static int part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
99{
100 struct mtd_part *part = mtd_to_part(mtd);
101
102 return part->parent->_unpoint(part->parent, from + part->offset, len);
103}
104
105static int part_read_oob(struct mtd_info *mtd, loff_t from,
106 struct mtd_oob_ops *ops)
107{
108 struct mtd_part *part = mtd_to_part(mtd);
109 struct mtd_ecc_stats stats;
110 int res;
111
112 stats = part->parent->ecc_stats;
113 res = part->parent->_read_oob(part->parent, from + part->offset, ops);
114 if (unlikely(mtd_is_eccerr(res)))
115 mtd->ecc_stats.failed +=
116 part->parent->ecc_stats.failed - stats.failed;
117 else
118 mtd->ecc_stats.corrected +=
119 part->parent->ecc_stats.corrected - stats.corrected;
120 return res;
121}
122
123static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
124 size_t len, size_t *retlen, u_char *buf)
125{
126 struct mtd_part *part = mtd_to_part(mtd);
127 return part->parent->_read_user_prot_reg(part->parent, from, len,
128 retlen, buf);
129}
130
131static int part_get_user_prot_info(struct mtd_info *mtd, size_t len,
132 size_t *retlen, struct otp_info *buf)
133{
134 struct mtd_part *part = mtd_to_part(mtd);
135 return part->parent->_get_user_prot_info(part->parent, len, retlen,
136 buf);
137}
138
139static int part_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
140 size_t len, size_t *retlen, u_char *buf)
141{
142 struct mtd_part *part = mtd_to_part(mtd);
143 return part->parent->_read_fact_prot_reg(part->parent, from, len,
144 retlen, buf);
145}
146
147static int part_get_fact_prot_info(struct mtd_info *mtd, size_t len,
148 size_t *retlen, struct otp_info *buf)
149{
150 struct mtd_part *part = mtd_to_part(mtd);
151 return part->parent->_get_fact_prot_info(part->parent, len, retlen,
152 buf);
153}
154
155static int part_write(struct mtd_info *mtd, loff_t to, size_t len,
156 size_t *retlen, const u_char *buf)
157{
158 struct mtd_part *part = mtd_to_part(mtd);
159 return part->parent->_write(part->parent, to + part->offset, len,
160 retlen, buf);
161}
162
163static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
164 size_t *retlen, const u_char *buf)
165{
166 struct mtd_part *part = mtd_to_part(mtd);
167 return part->parent->_panic_write(part->parent, to + part->offset, len,
168 retlen, buf);
169}
170
171static int part_write_oob(struct mtd_info *mtd, loff_t to,
172 struct mtd_oob_ops *ops)
173{
174 struct mtd_part *part = mtd_to_part(mtd);
175
176 return part->parent->_write_oob(part->parent, to + part->offset, ops);
177}
178
179static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
180 size_t len, size_t *retlen, u_char *buf)
181{
182 struct mtd_part *part = mtd_to_part(mtd);
183 return part->parent->_write_user_prot_reg(part->parent, from, len,
184 retlen, buf);
185}
186
187static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
188 size_t len)
189{
190 struct mtd_part *part = mtd_to_part(mtd);
191 return part->parent->_lock_user_prot_reg(part->parent, from, len);
192}
193
194static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,
195 unsigned long count, loff_t to, size_t *retlen)
196{
197 struct mtd_part *part = mtd_to_part(mtd);
198 return part->parent->_writev(part->parent, vecs, count,
199 to + part->offset, retlen);
200}
201
202static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
203{
204 struct mtd_part *part = mtd_to_part(mtd);
205 int ret;
206
207 instr->addr += part->offset;
208 ret = part->parent->_erase(part->parent, instr);
209 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
210 instr->fail_addr -= part->offset;
211 instr->addr -= part->offset;
212
213 return ret;
214}
215
216static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
217{
218 struct mtd_part *part = mtd_to_part(mtd);
219 return part->parent->_lock(part->parent, ofs + part->offset, len);
220}
221
222static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
223{
224 struct mtd_part *part = mtd_to_part(mtd);
225 return part->parent->_unlock(part->parent, ofs + part->offset, len);
226}
227
228static int part_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
229{
230 struct mtd_part *part = mtd_to_part(mtd);
231 return part->parent->_is_locked(part->parent, ofs + part->offset, len);
232}
233
234static void part_sync(struct mtd_info *mtd)
235{
236 struct mtd_part *part = mtd_to_part(mtd);
237 part->parent->_sync(part->parent);
238}
239
240static int part_suspend(struct mtd_info *mtd)
241{
242 struct mtd_part *part = mtd_to_part(mtd);
243 return part->parent->_suspend(part->parent);
244}
245
246static void part_resume(struct mtd_info *mtd)
247{
248 struct mtd_part *part = mtd_to_part(mtd);
249 part->parent->_resume(part->parent);
250}
251
252static int part_block_isreserved(struct mtd_info *mtd, loff_t ofs)
253{
254 struct mtd_part *part = mtd_to_part(mtd);
255 ofs += part->offset;
256 return part->parent->_block_isreserved(part->parent, ofs);
257}
258
259static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
260{
261 struct mtd_part *part = mtd_to_part(mtd);
262 ofs += part->offset;
263 return part->parent->_block_isbad(part->parent, ofs);
264}
265
266static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
267{
268 struct mtd_part *part = mtd_to_part(mtd);
269 int res;
270
271 ofs += part->offset;
272 res = part->parent->_block_markbad(part->parent, ofs);
273 if (!res)
274 mtd->ecc_stats.badblocks++;
275 return res;
276}
277
278static int part_get_device(struct mtd_info *mtd)
279{
280 struct mtd_part *part = mtd_to_part(mtd);
281 return part->parent->_get_device(part->parent);
282}
283
284static void part_put_device(struct mtd_info *mtd)
285{
286 struct mtd_part *part = mtd_to_part(mtd);
287 part->parent->_put_device(part->parent);
288}
289
290static int part_ooblayout_ecc(struct mtd_info *mtd, int section,
291 struct mtd_oob_region *oobregion)
292{
293 struct mtd_part *part = mtd_to_part(mtd);
294
295 return mtd_ooblayout_ecc(part->parent, section, oobregion);
296}
297
298static int part_ooblayout_free(struct mtd_info *mtd, int section,
299 struct mtd_oob_region *oobregion)
300{
301 struct mtd_part *part = mtd_to_part(mtd);
302
303 return mtd_ooblayout_free(part->parent, section, oobregion);
304}
305
306static const struct mtd_ooblayout_ops part_ooblayout_ops = {
307 .ecc = part_ooblayout_ecc,
308 .free = part_ooblayout_free,
309};
310
311static int part_max_bad_blocks(struct mtd_info *mtd, loff_t ofs, size_t len)
312{
313 struct mtd_part *part = mtd_to_part(mtd);
314
315 return part->parent->_max_bad_blocks(part->parent,
316 ofs + part->offset, len);
317}
318
319static inline void free_partition(struct mtd_part *p)
320{
321 kfree(p->mtd.name);
322 kfree(p);
323}
324
325/**
326 * mtd_parse_part - parse MTD partition looking for subpartitions
327 *
328 * @slave: part that is supposed to be a container and should be parsed
329 * @types: NULL-terminated array with names of partition parsers to try
330 *
331 * Some partitions are kind of containers with extra subpartitions (volumes).
332 * There can be various formats of such containers. This function tries to use
333 * specified parsers to analyze given partition and registers found
334 * subpartitions on success.
335 */
336static int mtd_parse_part(struct mtd_part *slave, const char *const *types)
337{
338 struct mtd_partitions parsed;
339 int err;
340
341 err = parse_mtd_partitions(&slave->mtd, types, &parsed, NULL);
342 if (err)
343 return err;
344 else if (!parsed.nr_parts)
345 return -ENOENT;
346
347 err = add_mtd_partitions(&slave->mtd, parsed.parts, parsed.nr_parts);
348
349 mtd_part_parser_cleanup(&parsed);
350
351 return err;
352}
353
354static struct mtd_part *allocate_partition(struct mtd_info *parent,
355 const struct mtd_partition *part, int partno,
356 uint64_t cur_offset)
357{
358 int wr_alignment = (parent->flags & MTD_NO_ERASE) ? parent->writesize :
359 parent->erasesize;
360 struct mtd_part *slave;
361 u32 remainder;
362 char *name;
363 u64 tmp;
364
365 /* allocate the partition structure */
366 slave = kzalloc(sizeof(*slave), GFP_KERNEL);
367 name = kstrdup(part->name, GFP_KERNEL);
368 if (!name || !slave) {
369 printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
370 parent->name);
371 kfree(name);
372 kfree(slave);
373 return ERR_PTR(-ENOMEM);
374 }
375
376 /* set up the MTD object for this partition */
377 slave->mtd.type = parent->type;
378 slave->mtd.flags = parent->flags & ~part->mask_flags;
379 slave->mtd.size = part->size;
380 slave->mtd.writesize = parent->writesize;
381 slave->mtd.writebufsize = parent->writebufsize;
382 slave->mtd.oobsize = parent->oobsize;
383 slave->mtd.oobavail = parent->oobavail;
384 slave->mtd.subpage_sft = parent->subpage_sft;
385 slave->mtd.pairing = parent->pairing;
386
387 slave->mtd.name = name;
388 slave->mtd.owner = parent->owner;
389
390 /* NOTE: Historically, we didn't arrange MTDs as a tree out of
391 * concern for showing the same data in multiple partitions.
392 * However, it is very useful to have the master node present,
393 * so the MTD_PARTITIONED_MASTER option allows that. The master
394 * will have device nodes etc only if this is set, so make the
395 * parent conditional on that option. Note, this is a way to
396 * distinguish between the master and the partition in sysfs.
397 */
398 slave->mtd.dev.parent = IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) || mtd_is_partition(parent) ?
399 &parent->dev :
400 parent->dev.parent;
401 slave->mtd.dev.of_node = part->of_node;
402
403 if (parent->_read)
404 slave->mtd._read = part_read;
405 if (parent->_write)
406 slave->mtd._write = part_write;
407
408 if (parent->_panic_write)
409 slave->mtd._panic_write = part_panic_write;
410
411 if (parent->_point && parent->_unpoint) {
412 slave->mtd._point = part_point;
413 slave->mtd._unpoint = part_unpoint;
414 }
415
416 if (parent->_read_oob)
417 slave->mtd._read_oob = part_read_oob;
418 if (parent->_write_oob)
419 slave->mtd._write_oob = part_write_oob;
420 if (parent->_read_user_prot_reg)
421 slave->mtd._read_user_prot_reg = part_read_user_prot_reg;
422 if (parent->_read_fact_prot_reg)
423 slave->mtd._read_fact_prot_reg = part_read_fact_prot_reg;
424 if (parent->_write_user_prot_reg)
425 slave->mtd._write_user_prot_reg = part_write_user_prot_reg;
426 if (parent->_lock_user_prot_reg)
427 slave->mtd._lock_user_prot_reg = part_lock_user_prot_reg;
428 if (parent->_get_user_prot_info)
429 slave->mtd._get_user_prot_info = part_get_user_prot_info;
430 if (parent->_get_fact_prot_info)
431 slave->mtd._get_fact_prot_info = part_get_fact_prot_info;
432 if (parent->_sync)
433 slave->mtd._sync = part_sync;
434 if (!partno && !parent->dev.class && parent->_suspend &&
435 parent->_resume) {
436 slave->mtd._suspend = part_suspend;
437 slave->mtd._resume = part_resume;
438 }
439 if (parent->_writev)
440 slave->mtd._writev = part_writev;
441 if (parent->_lock)
442 slave->mtd._lock = part_lock;
443 if (parent->_unlock)
444 slave->mtd._unlock = part_unlock;
445 if (parent->_is_locked)
446 slave->mtd._is_locked = part_is_locked;
447 if (parent->_block_isreserved)
448 slave->mtd._block_isreserved = part_block_isreserved;
449 if (parent->_block_isbad)
450 slave->mtd._block_isbad = part_block_isbad;
451 if (parent->_block_markbad)
452 slave->mtd._block_markbad = part_block_markbad;
453 if (parent->_max_bad_blocks)
454 slave->mtd._max_bad_blocks = part_max_bad_blocks;
455
456 if (parent->_get_device)
457 slave->mtd._get_device = part_get_device;
458 if (parent->_put_device)
459 slave->mtd._put_device = part_put_device;
460
461 slave->mtd._erase = part_erase;
462 slave->parent = parent;
463 slave->offset = part->offset;
464
465 if (slave->offset == MTDPART_OFS_APPEND)
466 slave->offset = cur_offset;
467 if (slave->offset == MTDPART_OFS_NXTBLK) {
468 tmp = cur_offset;
469 slave->offset = cur_offset;
470 remainder = do_div(tmp, wr_alignment);
471 if (remainder) {
472 slave->offset += wr_alignment - remainder;
473 printk(KERN_NOTICE "Moving partition %d: "
474 "0x%012llx -> 0x%012llx\n", partno,
475 (unsigned long long)cur_offset, (unsigned long long)slave->offset);
476 }
477 }
478 if (slave->offset == MTDPART_OFS_RETAIN) {
479 slave->offset = cur_offset;
480 if (parent->size - slave->offset >= slave->mtd.size) {
481 slave->mtd.size = parent->size - slave->offset
482 - slave->mtd.size;
483 } else {
484 printk(KERN_ERR "mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n",
485 part->name, parent->size - slave->offset,
486 slave->mtd.size);
487 /* register to preserve ordering */
488 goto out_register;
489 }
490 }
491 if (slave->mtd.size == MTDPART_SIZ_FULL)
492 slave->mtd.size = parent->size - slave->offset;
493
494 printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
495 (unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
496
497 /* let's do some sanity checks */
498 if (slave->offset >= parent->size) {
499 /* let's register it anyway to preserve ordering */
500 slave->offset = 0;
501 slave->mtd.size = 0;
502 printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
503 part->name);
504 goto out_register;
505 }
506 if (slave->offset + slave->mtd.size > parent->size) {
507 slave->mtd.size = parent->size - slave->offset;
508 printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
509 part->name, parent->name, (unsigned long long)slave->mtd.size);
510 }
511 if (parent->numeraseregions > 1) {
512 /* Deal with variable erase size stuff */
513 int i, max = parent->numeraseregions;
514 u64 end = slave->offset + slave->mtd.size;
515 struct mtd_erase_region_info *regions = parent->eraseregions;
516
517 /* Find the first erase regions which is part of this
518 * partition. */
519 for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
520 ;
521 /* The loop searched for the region _behind_ the first one */
522 if (i > 0)
523 i--;
524
525 /* Pick biggest erasesize */
526 for (; i < max && regions[i].offset < end; i++) {
527 if (slave->mtd.erasesize < regions[i].erasesize) {
528 slave->mtd.erasesize = regions[i].erasesize;
529 }
530 }
531 BUG_ON(slave->mtd.erasesize == 0);
532 } else {
533 /* Single erase size */
534 slave->mtd.erasesize = parent->erasesize;
535 }
536
537 /*
538 * Slave erasesize might differ from the master one if the master
539 * exposes several regions with different erasesize. Adjust
540 * wr_alignment accordingly.
541 */
542 if (!(slave->mtd.flags & MTD_NO_ERASE))
543 wr_alignment = slave->mtd.erasesize;
544
545 tmp = slave->offset;
546 remainder = do_div(tmp, wr_alignment);
547 if ((slave->mtd.flags & MTD_WRITEABLE) && remainder) {
548 /* Doesn't start on a boundary of major erase size */
549 /* FIXME: Let it be writable if it is on a boundary of
550 * _minor_ erase size though */
551 slave->mtd.flags &= ~MTD_WRITEABLE;
552 printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase/write block boundary -- force read-only\n",
553 part->name);
554 }
555
556 tmp = slave->mtd.size;
557 remainder = do_div(tmp, wr_alignment);
558 if ((slave->mtd.flags & MTD_WRITEABLE) && remainder) {
559 slave->mtd.flags &= ~MTD_WRITEABLE;
560 printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase/write block -- force read-only\n",
561 part->name);
562 }
563
564 mtd_set_ooblayout(&slave->mtd, &part_ooblayout_ops);
565 slave->mtd.ecc_step_size = parent->ecc_step_size;
566 slave->mtd.ecc_strength = parent->ecc_strength;
567 slave->mtd.bitflip_threshold = parent->bitflip_threshold;
568
569 if (parent->_block_isbad) {
570 uint64_t offs = 0;
571
572 while (offs < slave->mtd.size) {
573 if (mtd_block_isreserved(parent, offs + slave->offset))
574 slave->mtd.ecc_stats.bbtblocks++;
575 else if (mtd_block_isbad(parent, offs + slave->offset))
576 slave->mtd.ecc_stats.badblocks++;
577 offs += slave->mtd.erasesize;
578 }
579 }
580
581out_register:
582 return slave;
583}
584
585static ssize_t mtd_partition_offset_show(struct device *dev,
586 struct device_attribute *attr, char *buf)
587{
588 struct mtd_info *mtd = dev_get_drvdata(dev);
589 struct mtd_part *part = mtd_to_part(mtd);
590 return snprintf(buf, PAGE_SIZE, "%lld\n", part->offset);
591}
592
593static DEVICE_ATTR(offset, S_IRUGO, mtd_partition_offset_show, NULL);
594
595static const struct attribute *mtd_partition_attrs[] = {
596 &dev_attr_offset.attr,
597 NULL
598};
599
600static int mtd_add_partition_attrs(struct mtd_part *new)
601{
602 int ret = sysfs_create_files(&new->mtd.dev.kobj, mtd_partition_attrs);
603 if (ret)
604 printk(KERN_WARNING
605 "mtd: failed to create partition attrs, err=%d\n", ret);
606 return ret;
607}
608
609int mtd_add_partition(struct mtd_info *parent, const char *name,
610 long long offset, long long length)
611{
612 struct mtd_partition part;
613 struct mtd_part *new;
614 int ret = 0;
615
616 /* the direct offset is expected */
617 if (offset == MTDPART_OFS_APPEND ||
618 offset == MTDPART_OFS_NXTBLK)
619 return -EINVAL;
620
621 if (length == MTDPART_SIZ_FULL)
622 length = parent->size - offset;
623
624 if (length <= 0)
625 return -EINVAL;
626
627 memset(&part, 0, sizeof(part));
628 part.name = name;
629 part.size = length;
630 part.offset = offset;
631
632 new = allocate_partition(parent, &part, -1, offset);
633 if (IS_ERR(new))
634 return PTR_ERR(new);
635
636 mutex_lock(&mtd_partitions_mutex);
637 list_add(&new->list, &mtd_partitions);
638 mutex_unlock(&mtd_partitions_mutex);
639
640 add_mtd_device(&new->mtd);
641
642 mtd_add_partition_attrs(new);
643
644 return ret;
645}
646EXPORT_SYMBOL_GPL(mtd_add_partition);
647
648/**
649 * __mtd_del_partition - delete MTD partition
650 *
651 * @priv: internal MTD struct for partition to be deleted
652 *
653 * This function must be called with the partitions mutex locked.
654 */
655static int __mtd_del_partition(struct mtd_part *priv)
656{
657 struct mtd_part *child, *next;
658 int err;
659
660 list_for_each_entry_safe(child, next, &mtd_partitions, list) {
661 if (child->parent == &priv->mtd) {
662 err = __mtd_del_partition(child);
663 if (err)
664 return err;
665 }
666 }
667
668 sysfs_remove_files(&priv->mtd.dev.kobj, mtd_partition_attrs);
669
670 err = del_mtd_device(&priv->mtd);
671 if (err)
672 return err;
673
674 list_del(&priv->list);
675 free_partition(priv);
676
677 return 0;
678}
679
680/*
681 * This function unregisters and destroy all slave MTD objects which are
682 * attached to the given MTD object.
683 */
684int del_mtd_partitions(struct mtd_info *mtd)
685{
686 struct mtd_part *slave, *next;
687 int ret, err = 0;
688
689 mutex_lock(&mtd_partitions_mutex);
690 list_for_each_entry_safe(slave, next, &mtd_partitions, list)
691 if (slave->parent == mtd) {
692 ret = __mtd_del_partition(slave);
693 if (ret < 0)
694 err = ret;
695 }
696 mutex_unlock(&mtd_partitions_mutex);
697
698 return err;
699}
700
701int mtd_del_partition(struct mtd_info *mtd, int partno)
702{
703 struct mtd_part *slave, *next;
704 int ret = -EINVAL;
705
706 mutex_lock(&mtd_partitions_mutex);
707 list_for_each_entry_safe(slave, next, &mtd_partitions, list)
708 if ((slave->parent == mtd) &&
709 (slave->mtd.index == partno)) {
710 ret = __mtd_del_partition(slave);
711 break;
712 }
713 mutex_unlock(&mtd_partitions_mutex);
714
715 return ret;
716}
717EXPORT_SYMBOL_GPL(mtd_del_partition);
718
719/*
720 * This function, given a master MTD object and a partition table, creates
721 * and registers slave MTD objects which are bound to the master according to
722 * the partition definitions.
723 *
724 * For historical reasons, this function's caller only registers the master
725 * if the MTD_PARTITIONED_MASTER config option is set.
726 */
727
728int add_mtd_partitions(struct mtd_info *master,
729 const struct mtd_partition *parts,
730 int nbparts)
731{
732 struct mtd_part *slave;
733 uint64_t cur_offset = 0;
734 int i;
735
736 printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
737
738 for (i = 0; i < nbparts; i++) {
739 slave = allocate_partition(master, parts + i, i, cur_offset);
740 if (IS_ERR(slave)) {
741 del_mtd_partitions(master);
742 return PTR_ERR(slave);
743 }
744
745 mutex_lock(&mtd_partitions_mutex);
746 list_add(&slave->list, &mtd_partitions);
747 mutex_unlock(&mtd_partitions_mutex);
748
749 add_mtd_device(&slave->mtd);
750 mtd_add_partition_attrs(slave);
751 if (parts[i].types)
752 mtd_parse_part(slave, parts[i].types);
753
754 cur_offset = slave->offset + slave->mtd.size;
755 }
756
757 return 0;
758}
759
760static DEFINE_SPINLOCK(part_parser_lock);
761static LIST_HEAD(part_parsers);
762
763static struct mtd_part_parser *mtd_part_parser_get(const char *name)
764{
765 struct mtd_part_parser *p, *ret = NULL;
766
767 spin_lock(&part_parser_lock);
768
769 list_for_each_entry(p, &part_parsers, list)
770 if (!strcmp(p->name, name) && try_module_get(p->owner)) {
771 ret = p;
772 break;
773 }
774
775 spin_unlock(&part_parser_lock);
776
777 return ret;
778}
779
780static inline void mtd_part_parser_put(const struct mtd_part_parser *p)
781{
782 module_put(p->owner);
783}
784
785/*
786 * Many partition parsers just expected the core to kfree() all their data in
787 * one chunk. Do that by default.
788 */
789static void mtd_part_parser_cleanup_default(const struct mtd_partition *pparts,
790 int nr_parts)
791{
792 kfree(pparts);
793}
794
795int __register_mtd_parser(struct mtd_part_parser *p, struct module *owner)
796{
797 p->owner = owner;
798
799 if (!p->cleanup)
800 p->cleanup = &mtd_part_parser_cleanup_default;
801
802 spin_lock(&part_parser_lock);
803 list_add(&p->list, &part_parsers);
804 spin_unlock(&part_parser_lock);
805
806 return 0;
807}
808EXPORT_SYMBOL_GPL(__register_mtd_parser);
809
810void deregister_mtd_parser(struct mtd_part_parser *p)
811{
812 spin_lock(&part_parser_lock);
813 list_del(&p->list);
814 spin_unlock(&part_parser_lock);
815}
816EXPORT_SYMBOL_GPL(deregister_mtd_parser);
817
818/*
819 * Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
820 * are changing this array!
821 */
822static const char * const default_mtd_part_types[] = {
823 "cmdlinepart",
824 "ofpart",
825 NULL
826};
827
828static int mtd_part_do_parse(struct mtd_part_parser *parser,
829 struct mtd_info *master,
830 struct mtd_partitions *pparts,
831 struct mtd_part_parser_data *data)
832{
833 int ret;
834
835 ret = (*parser->parse_fn)(master, &pparts->parts, data);
836 pr_debug("%s: parser %s: %i\n", master->name, parser->name, ret);
837 if (ret <= 0)
838 return ret;
839
840 pr_notice("%d %s partitions found on MTD device %s\n", ret,
841 parser->name, master->name);
842
843 pparts->nr_parts = ret;
844 pparts->parser = parser;
845
846 return ret;
847}
848
849/**
850 * mtd_part_get_compatible_parser - find MTD parser by a compatible string
851 *
852 * @compat: compatible string describing partitions in a device tree
853 *
854 * MTD parsers can specify supported partitions by providing a table of
855 * compatibility strings. This function finds a parser that advertises support
856 * for a passed value of "compatible".
857 */
858static struct mtd_part_parser *mtd_part_get_compatible_parser(const char *compat)
859{
860 struct mtd_part_parser *p, *ret = NULL;
861
862 spin_lock(&part_parser_lock);
863
864 list_for_each_entry(p, &part_parsers, list) {
865 const struct of_device_id *matches;
866
867 matches = p->of_match_table;
868 if (!matches)
869 continue;
870
871 for (; matches->compatible[0]; matches++) {
872 if (!strcmp(matches->compatible, compat) &&
873 try_module_get(p->owner)) {
874 ret = p;
875 break;
876 }
877 }
878
879 if (ret)
880 break;
881 }
882
883 spin_unlock(&part_parser_lock);
884
885 return ret;
886}
887
888static int mtd_part_of_parse(struct mtd_info *master,
889 struct mtd_partitions *pparts)
890{
891 struct mtd_part_parser *parser;
892 struct device_node *np;
893 struct property *prop;
894 const char *compat;
895 const char *fixed = "fixed-partitions";
896 int ret, err = 0;
897
898 np = of_get_child_by_name(mtd_get_of_node(master), "partitions");
899 of_property_for_each_string(np, "compatible", prop, compat) {
900 parser = mtd_part_get_compatible_parser(compat);
901 if (!parser)
902 continue;
903 ret = mtd_part_do_parse(parser, master, pparts, NULL);
904 if (ret > 0) {
905 of_node_put(np);
906 return ret;
907 }
908 mtd_part_parser_put(parser);
909 if (ret < 0 && !err)
910 err = ret;
911 }
912 of_node_put(np);
913
914 /*
915 * For backward compatibility we have to try the "fixed-partitions"
916 * parser. It supports old DT format with partitions specified as a
917 * direct subnodes of a flash device DT node without any compatibility
918 * specified we could match.
919 */
920 parser = mtd_part_parser_get(fixed);
921 if (!parser && !request_module("%s", fixed))
922 parser = mtd_part_parser_get(fixed);
923 if (parser) {
924 ret = mtd_part_do_parse(parser, master, pparts, NULL);
925 if (ret > 0)
926 return ret;
927 mtd_part_parser_put(parser);
928 if (ret < 0 && !err)
929 err = ret;
930 }
931
932 return err;
933}
934
935/**
936 * parse_mtd_partitions - parse MTD partitions
937 * @master: the master partition (describes whole MTD device)
938 * @types: names of partition parsers to try or %NULL
939 * @pparts: info about partitions found is returned here
940 * @data: MTD partition parser-specific data
941 *
942 * This function tries to find partition on MTD device @master. It uses MTD
943 * partition parsers, specified in @types. However, if @types is %NULL, then
944 * the default list of parsers is used. The default list contains only the
945 * "cmdlinepart" and "ofpart" parsers ATM.
946 * Note: If there are more then one parser in @types, the kernel only takes the
947 * partitions parsed out by the first parser.
948 *
949 * This function may return:
950 * o a negative error code in case of failure
951 * o zero otherwise, and @pparts will describe the partitions, number of
952 * partitions, and the parser which parsed them. Caller must release
953 * resources with mtd_part_parser_cleanup() when finished with the returned
954 * data.
955 */
956int parse_mtd_partitions(struct mtd_info *master, const char *const *types,
957 struct mtd_partitions *pparts,
958 struct mtd_part_parser_data *data)
959{
960 struct mtd_part_parser *parser;
961 int ret, err = 0;
962
963 if (!types)
964 types = default_mtd_part_types;
965
966 for ( ; *types; types++) {
967 /*
968 * ofpart is a special type that means OF partitioning info
969 * should be used. It requires a bit different logic so it is
970 * handled in a separated function.
971 */
972 if (!strcmp(*types, "ofpart")) {
973 ret = mtd_part_of_parse(master, pparts);
974 } else {
975 pr_debug("%s: parsing partitions %s\n", master->name,
976 *types);
977 parser = mtd_part_parser_get(*types);
978 if (!parser && !request_module("%s", *types))
979 parser = mtd_part_parser_get(*types);
980 pr_debug("%s: got parser %s\n", master->name,
981 parser ? parser->name : NULL);
982 if (!parser)
983 continue;
984 ret = mtd_part_do_parse(parser, master, pparts, data);
985 if (ret <= 0)
986 mtd_part_parser_put(parser);
987 }
988 /* Found partitions! */
989 if (ret > 0)
990 return 0;
991 /*
992 * Stash the first error we see; only report it if no parser
993 * succeeds
994 */
995 if (ret < 0 && !err)
996 err = ret;
997 }
998 return err;
999}
1000
1001void mtd_part_parser_cleanup(struct mtd_partitions *parts)
1002{
1003 const struct mtd_part_parser *parser;
1004
1005 if (!parts)
1006 return;
1007
1008 parser = parts->parser;
1009 if (parser) {
1010 if (parser->cleanup)
1011 parser->cleanup(parts->parts, parts->nr_parts);
1012
1013 mtd_part_parser_put(parser);
1014 }
1015}
1016
1017int mtd_is_partition(const struct mtd_info *mtd)
1018{
1019 struct mtd_part *part;
1020 int ispart = 0;
1021
1022 mutex_lock(&mtd_partitions_mutex);
1023 list_for_each_entry(part, &mtd_partitions, list)
1024 if (&part->mtd == mtd) {
1025 ispart = 1;
1026 break;
1027 }
1028 mutex_unlock(&mtd_partitions_mutex);
1029
1030 return ispart;
1031}
1032EXPORT_SYMBOL_GPL(mtd_is_partition);
1033
1034/* Returns the size of the entire flash chip */
1035uint64_t mtd_get_device_size(const struct mtd_info *mtd)
1036{
1037 if (!mtd_is_partition(mtd))
1038 return mtd->size;
1039
1040 return mtd_get_device_size(mtd_to_part(mtd)->parent);
1041}
1042EXPORT_SYMBOL_GPL(mtd_get_device_size);