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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
21#include "mtdcore.h"
22
23/* Our partition linked list */
24static LIST_HEAD(mtd_partitions);
25static DEFINE_MUTEX(mtd_partitions_mutex);
26
27/**
28 * struct mtd_part - our partition node structure
29 *
30 * @mtd: struct holding partition details
31 * @parent: parent mtd - flash device or another partition
32 * @offset: partition offset relative to the *flash device*
33 */
34struct mtd_part {
35 struct mtd_info mtd;
36 struct mtd_info *parent;
37 uint64_t offset;
38 struct list_head list;
39};
40
41/*
42 * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
43 * the pointer to that structure.
44 */
45static inline struct mtd_part *mtd_to_part(const struct mtd_info *mtd)
46{
47 return container_of(mtd, struct mtd_part, mtd);
48}
49
50static u64 part_absolute_offset(struct mtd_info *mtd)
51{
52 struct mtd_part *part = mtd_to_part(mtd);
53
54 if (!mtd_is_partition(mtd))
55 return 0;
56
57 return part_absolute_offset(part->parent) + part->offset;
58}
59
60/*
61 * MTD methods which simply translate the effective address and pass through
62 * to the _real_ device.
63 */
64
65static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
66 size_t *retlen, u_char *buf)
67{
68 struct mtd_part *part = mtd_to_part(mtd);
69 struct mtd_ecc_stats stats;
70 int res;
71
72 stats = part->parent->ecc_stats;
73 res = part->parent->_read(part->parent, from + part->offset, len,
74 retlen, buf);
75 if (unlikely(mtd_is_eccerr(res)))
76 mtd->ecc_stats.failed +=
77 part->parent->ecc_stats.failed - stats.failed;
78 else
79 mtd->ecc_stats.corrected +=
80 part->parent->ecc_stats.corrected - stats.corrected;
81 return res;
82}
83
84static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
85 size_t *retlen, void **virt, resource_size_t *phys)
86{
87 struct mtd_part *part = mtd_to_part(mtd);
88
89 return part->parent->_point(part->parent, from + part->offset, len,
90 retlen, virt, phys);
91}
92
93static int part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
94{
95 struct mtd_part *part = mtd_to_part(mtd);
96
97 return part->parent->_unpoint(part->parent, from + part->offset, len);
98}
99
100static int part_read_oob(struct mtd_info *mtd, loff_t from,
101 struct mtd_oob_ops *ops)
102{
103 struct mtd_part *part = mtd_to_part(mtd);
104 struct mtd_ecc_stats stats;
105 int res;
106
107 stats = part->parent->ecc_stats;
108 res = part->parent->_read_oob(part->parent, from + part->offset, ops);
109 if (unlikely(mtd_is_eccerr(res)))
110 mtd->ecc_stats.failed +=
111 part->parent->ecc_stats.failed - stats.failed;
112 else
113 mtd->ecc_stats.corrected +=
114 part->parent->ecc_stats.corrected - stats.corrected;
115 return res;
116}
117
118static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
119 size_t len, size_t *retlen, u_char *buf)
120{
121 struct mtd_part *part = mtd_to_part(mtd);
122 return part->parent->_read_user_prot_reg(part->parent, from, len,
123 retlen, buf);
124}
125
126static int part_get_user_prot_info(struct mtd_info *mtd, size_t len,
127 size_t *retlen, struct otp_info *buf)
128{
129 struct mtd_part *part = mtd_to_part(mtd);
130 return part->parent->_get_user_prot_info(part->parent, len, retlen,
131 buf);
132}
133
134static int part_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
135 size_t len, size_t *retlen, u_char *buf)
136{
137 struct mtd_part *part = mtd_to_part(mtd);
138 return part->parent->_read_fact_prot_reg(part->parent, from, len,
139 retlen, buf);
140}
141
142static int part_get_fact_prot_info(struct mtd_info *mtd, size_t len,
143 size_t *retlen, struct otp_info *buf)
144{
145 struct mtd_part *part = mtd_to_part(mtd);
146 return part->parent->_get_fact_prot_info(part->parent, len, retlen,
147 buf);
148}
149
150static int part_write(struct mtd_info *mtd, loff_t to, size_t len,
151 size_t *retlen, const u_char *buf)
152{
153 struct mtd_part *part = mtd_to_part(mtd);
154 return part->parent->_write(part->parent, to + part->offset, len,
155 retlen, buf);
156}
157
158static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
159 size_t *retlen, const u_char *buf)
160{
161 struct mtd_part *part = mtd_to_part(mtd);
162 return part->parent->_panic_write(part->parent, to + part->offset, len,
163 retlen, buf);
164}
165
166static int part_write_oob(struct mtd_info *mtd, loff_t to,
167 struct mtd_oob_ops *ops)
168{
169 struct mtd_part *part = mtd_to_part(mtd);
170
171 return part->parent->_write_oob(part->parent, to + part->offset, ops);
172}
173
174static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
175 size_t len, size_t *retlen, u_char *buf)
176{
177 struct mtd_part *part = mtd_to_part(mtd);
178 return part->parent->_write_user_prot_reg(part->parent, from, len,
179 retlen, buf);
180}
181
182static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
183 size_t len)
184{
185 struct mtd_part *part = mtd_to_part(mtd);
186 return part->parent->_lock_user_prot_reg(part->parent, from, len);
187}
188
189static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,
190 unsigned long count, loff_t to, size_t *retlen)
191{
192 struct mtd_part *part = mtd_to_part(mtd);
193 return part->parent->_writev(part->parent, vecs, count,
194 to + part->offset, retlen);
195}
196
197static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
198{
199 struct mtd_part *part = mtd_to_part(mtd);
200 int ret;
201
202 instr->addr += part->offset;
203 ret = part->parent->_erase(part->parent, instr);
204 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
205 instr->fail_addr -= part->offset;
206 instr->addr -= part->offset;
207
208 return ret;
209}
210
211static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
212{
213 struct mtd_part *part = mtd_to_part(mtd);
214 return part->parent->_lock(part->parent, ofs + part->offset, len);
215}
216
217static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
218{
219 struct mtd_part *part = mtd_to_part(mtd);
220 return part->parent->_unlock(part->parent, ofs + part->offset, len);
221}
222
223static int part_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
224{
225 struct mtd_part *part = mtd_to_part(mtd);
226 return part->parent->_is_locked(part->parent, ofs + part->offset, len);
227}
228
229static void part_sync(struct mtd_info *mtd)
230{
231 struct mtd_part *part = mtd_to_part(mtd);
232 part->parent->_sync(part->parent);
233}
234
235static int part_suspend(struct mtd_info *mtd)
236{
237 struct mtd_part *part = mtd_to_part(mtd);
238 return part->parent->_suspend(part->parent);
239}
240
241static void part_resume(struct mtd_info *mtd)
242{
243 struct mtd_part *part = mtd_to_part(mtd);
244 part->parent->_resume(part->parent);
245}
246
247static int part_block_isreserved(struct mtd_info *mtd, loff_t ofs)
248{
249 struct mtd_part *part = mtd_to_part(mtd);
250 ofs += part->offset;
251 return part->parent->_block_isreserved(part->parent, ofs);
252}
253
254static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
255{
256 struct mtd_part *part = mtd_to_part(mtd);
257 ofs += part->offset;
258 return part->parent->_block_isbad(part->parent, ofs);
259}
260
261static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
262{
263 struct mtd_part *part = mtd_to_part(mtd);
264 int res;
265
266 ofs += part->offset;
267 res = part->parent->_block_markbad(part->parent, ofs);
268 if (!res)
269 mtd->ecc_stats.badblocks++;
270 return res;
271}
272
273static int part_get_device(struct mtd_info *mtd)
274{
275 struct mtd_part *part = mtd_to_part(mtd);
276 return part->parent->_get_device(part->parent);
277}
278
279static void part_put_device(struct mtd_info *mtd)
280{
281 struct mtd_part *part = mtd_to_part(mtd);
282 part->parent->_put_device(part->parent);
283}
284
285static int part_ooblayout_ecc(struct mtd_info *mtd, int section,
286 struct mtd_oob_region *oobregion)
287{
288 struct mtd_part *part = mtd_to_part(mtd);
289
290 return mtd_ooblayout_ecc(part->parent, section, oobregion);
291}
292
293static int part_ooblayout_free(struct mtd_info *mtd, int section,
294 struct mtd_oob_region *oobregion)
295{
296 struct mtd_part *part = mtd_to_part(mtd);
297
298 return mtd_ooblayout_free(part->parent, section, oobregion);
299}
300
301static const struct mtd_ooblayout_ops part_ooblayout_ops = {
302 .ecc = part_ooblayout_ecc,
303 .free = part_ooblayout_free,
304};
305
306static int part_max_bad_blocks(struct mtd_info *mtd, loff_t ofs, size_t len)
307{
308 struct mtd_part *part = mtd_to_part(mtd);
309
310 return part->parent->_max_bad_blocks(part->parent,
311 ofs + part->offset, len);
312}
313
314static inline void free_partition(struct mtd_part *p)
315{
316 kfree(p->mtd.name);
317 kfree(p);
318}
319
320static struct mtd_part *allocate_partition(struct mtd_info *parent,
321 const struct mtd_partition *part, int partno,
322 uint64_t cur_offset)
323{
324 int wr_alignment = (parent->flags & MTD_NO_ERASE) ? parent->writesize :
325 parent->erasesize;
326 struct mtd_part *slave;
327 u32 remainder;
328 char *name;
329 u64 tmp;
330
331 /* allocate the partition structure */
332 slave = kzalloc(sizeof(*slave), GFP_KERNEL);
333 name = kstrdup(part->name, GFP_KERNEL);
334 if (!name || !slave) {
335 printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
336 parent->name);
337 kfree(name);
338 kfree(slave);
339 return ERR_PTR(-ENOMEM);
340 }
341
342 /* set up the MTD object for this partition */
343 slave->mtd.type = parent->type;
344 slave->mtd.flags = parent->orig_flags & ~part->mask_flags;
345 slave->mtd.orig_flags = slave->mtd.flags;
346 slave->mtd.size = part->size;
347 slave->mtd.writesize = parent->writesize;
348 slave->mtd.writebufsize = parent->writebufsize;
349 slave->mtd.oobsize = parent->oobsize;
350 slave->mtd.oobavail = parent->oobavail;
351 slave->mtd.subpage_sft = parent->subpage_sft;
352 slave->mtd.pairing = parent->pairing;
353
354 slave->mtd.name = name;
355 slave->mtd.owner = parent->owner;
356
357 /* NOTE: Historically, we didn't arrange MTDs as a tree out of
358 * concern for showing the same data in multiple partitions.
359 * However, it is very useful to have the master node present,
360 * so the MTD_PARTITIONED_MASTER option allows that. The master
361 * will have device nodes etc only if this is set, so make the
362 * parent conditional on that option. Note, this is a way to
363 * distinguish between the master and the partition in sysfs.
364 */
365 slave->mtd.dev.parent = IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) || mtd_is_partition(parent) ?
366 &parent->dev :
367 parent->dev.parent;
368 slave->mtd.dev.of_node = part->of_node;
369
370 if (parent->_read)
371 slave->mtd._read = part_read;
372 if (parent->_write)
373 slave->mtd._write = part_write;
374
375 if (parent->_panic_write)
376 slave->mtd._panic_write = part_panic_write;
377
378 if (parent->_point && parent->_unpoint) {
379 slave->mtd._point = part_point;
380 slave->mtd._unpoint = part_unpoint;
381 }
382
383 if (parent->_read_oob)
384 slave->mtd._read_oob = part_read_oob;
385 if (parent->_write_oob)
386 slave->mtd._write_oob = part_write_oob;
387 if (parent->_read_user_prot_reg)
388 slave->mtd._read_user_prot_reg = part_read_user_prot_reg;
389 if (parent->_read_fact_prot_reg)
390 slave->mtd._read_fact_prot_reg = part_read_fact_prot_reg;
391 if (parent->_write_user_prot_reg)
392 slave->mtd._write_user_prot_reg = part_write_user_prot_reg;
393 if (parent->_lock_user_prot_reg)
394 slave->mtd._lock_user_prot_reg = part_lock_user_prot_reg;
395 if (parent->_get_user_prot_info)
396 slave->mtd._get_user_prot_info = part_get_user_prot_info;
397 if (parent->_get_fact_prot_info)
398 slave->mtd._get_fact_prot_info = part_get_fact_prot_info;
399 if (parent->_sync)
400 slave->mtd._sync = part_sync;
401 if (!partno && !parent->dev.class && parent->_suspend &&
402 parent->_resume) {
403 slave->mtd._suspend = part_suspend;
404 slave->mtd._resume = part_resume;
405 }
406 if (parent->_writev)
407 slave->mtd._writev = part_writev;
408 if (parent->_lock)
409 slave->mtd._lock = part_lock;
410 if (parent->_unlock)
411 slave->mtd._unlock = part_unlock;
412 if (parent->_is_locked)
413 slave->mtd._is_locked = part_is_locked;
414 if (parent->_block_isreserved)
415 slave->mtd._block_isreserved = part_block_isreserved;
416 if (parent->_block_isbad)
417 slave->mtd._block_isbad = part_block_isbad;
418 if (parent->_block_markbad)
419 slave->mtd._block_markbad = part_block_markbad;
420 if (parent->_max_bad_blocks)
421 slave->mtd._max_bad_blocks = part_max_bad_blocks;
422
423 if (parent->_get_device)
424 slave->mtd._get_device = part_get_device;
425 if (parent->_put_device)
426 slave->mtd._put_device = part_put_device;
427
428 slave->mtd._erase = part_erase;
429 slave->parent = parent;
430 slave->offset = part->offset;
431
432 if (slave->offset == MTDPART_OFS_APPEND)
433 slave->offset = cur_offset;
434 if (slave->offset == MTDPART_OFS_NXTBLK) {
435 tmp = cur_offset;
436 slave->offset = cur_offset;
437 remainder = do_div(tmp, wr_alignment);
438 if (remainder) {
439 slave->offset += wr_alignment - remainder;
440 printk(KERN_NOTICE "Moving partition %d: "
441 "0x%012llx -> 0x%012llx\n", partno,
442 (unsigned long long)cur_offset, (unsigned long long)slave->offset);
443 }
444 }
445 if (slave->offset == MTDPART_OFS_RETAIN) {
446 slave->offset = cur_offset;
447 if (parent->size - slave->offset >= slave->mtd.size) {
448 slave->mtd.size = parent->size - slave->offset
449 - slave->mtd.size;
450 } else {
451 printk(KERN_ERR "mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n",
452 part->name, parent->size - slave->offset,
453 slave->mtd.size);
454 /* register to preserve ordering */
455 goto out_register;
456 }
457 }
458 if (slave->mtd.size == MTDPART_SIZ_FULL)
459 slave->mtd.size = parent->size - slave->offset;
460
461 printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
462 (unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
463
464 /* let's do some sanity checks */
465 if (slave->offset >= parent->size) {
466 /* let's register it anyway to preserve ordering */
467 slave->offset = 0;
468 slave->mtd.size = 0;
469
470 /* Initialize ->erasesize to make add_mtd_device() happy. */
471 slave->mtd.erasesize = parent->erasesize;
472
473 printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
474 part->name);
475 goto out_register;
476 }
477 if (slave->offset + slave->mtd.size > parent->size) {
478 slave->mtd.size = parent->size - slave->offset;
479 printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
480 part->name, parent->name, (unsigned long long)slave->mtd.size);
481 }
482 if (parent->numeraseregions > 1) {
483 /* Deal with variable erase size stuff */
484 int i, max = parent->numeraseregions;
485 u64 end = slave->offset + slave->mtd.size;
486 struct mtd_erase_region_info *regions = parent->eraseregions;
487
488 /* Find the first erase regions which is part of this
489 * partition. */
490 for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
491 ;
492 /* The loop searched for the region _behind_ the first one */
493 if (i > 0)
494 i--;
495
496 /* Pick biggest erasesize */
497 for (; i < max && regions[i].offset < end; i++) {
498 if (slave->mtd.erasesize < regions[i].erasesize) {
499 slave->mtd.erasesize = regions[i].erasesize;
500 }
501 }
502 BUG_ON(slave->mtd.erasesize == 0);
503 } else {
504 /* Single erase size */
505 slave->mtd.erasesize = parent->erasesize;
506 }
507
508 /*
509 * Slave erasesize might differ from the master one if the master
510 * exposes several regions with different erasesize. Adjust
511 * wr_alignment accordingly.
512 */
513 if (!(slave->mtd.flags & MTD_NO_ERASE))
514 wr_alignment = slave->mtd.erasesize;
515
516 tmp = part_absolute_offset(parent) + slave->offset;
517 remainder = do_div(tmp, wr_alignment);
518 if ((slave->mtd.flags & MTD_WRITEABLE) && remainder) {
519 /* Doesn't start on a boundary of major erase size */
520 /* FIXME: Let it be writable if it is on a boundary of
521 * _minor_ erase size though */
522 slave->mtd.flags &= ~MTD_WRITEABLE;
523 printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase/write block boundary -- force read-only\n",
524 part->name);
525 }
526
527 tmp = part_absolute_offset(parent) + slave->mtd.size;
528 remainder = do_div(tmp, wr_alignment);
529 if ((slave->mtd.flags & MTD_WRITEABLE) && remainder) {
530 slave->mtd.flags &= ~MTD_WRITEABLE;
531 printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase/write block -- force read-only\n",
532 part->name);
533 }
534
535 mtd_set_ooblayout(&slave->mtd, &part_ooblayout_ops);
536 slave->mtd.ecc_step_size = parent->ecc_step_size;
537 slave->mtd.ecc_strength = parent->ecc_strength;
538 slave->mtd.bitflip_threshold = parent->bitflip_threshold;
539
540 if (parent->_block_isbad) {
541 uint64_t offs = 0;
542
543 while (offs < slave->mtd.size) {
544 if (mtd_block_isreserved(parent, offs + slave->offset))
545 slave->mtd.ecc_stats.bbtblocks++;
546 else if (mtd_block_isbad(parent, offs + slave->offset))
547 slave->mtd.ecc_stats.badblocks++;
548 offs += slave->mtd.erasesize;
549 }
550 }
551
552out_register:
553 return slave;
554}
555
556static ssize_t mtd_partition_offset_show(struct device *dev,
557 struct device_attribute *attr, char *buf)
558{
559 struct mtd_info *mtd = dev_get_drvdata(dev);
560 struct mtd_part *part = mtd_to_part(mtd);
561 return snprintf(buf, PAGE_SIZE, "%llu\n", part->offset);
562}
563
564static DEVICE_ATTR(offset, S_IRUGO, mtd_partition_offset_show, NULL);
565
566static const struct attribute *mtd_partition_attrs[] = {
567 &dev_attr_offset.attr,
568 NULL
569};
570
571static int mtd_add_partition_attrs(struct mtd_part *new)
572{
573 int ret = sysfs_create_files(&new->mtd.dev.kobj, mtd_partition_attrs);
574 if (ret)
575 printk(KERN_WARNING
576 "mtd: failed to create partition attrs, err=%d\n", ret);
577 return ret;
578}
579
580int mtd_add_partition(struct mtd_info *parent, const char *name,
581 long long offset, long long length)
582{
583 struct mtd_partition part;
584 struct mtd_part *new;
585 int ret = 0;
586
587 /* the direct offset is expected */
588 if (offset == MTDPART_OFS_APPEND ||
589 offset == MTDPART_OFS_NXTBLK)
590 return -EINVAL;
591
592 if (length == MTDPART_SIZ_FULL)
593 length = parent->size - offset;
594
595 if (length <= 0)
596 return -EINVAL;
597
598 memset(&part, 0, sizeof(part));
599 part.name = name;
600 part.size = length;
601 part.offset = offset;
602
603 new = allocate_partition(parent, &part, -1, offset);
604 if (IS_ERR(new))
605 return PTR_ERR(new);
606
607 mutex_lock(&mtd_partitions_mutex);
608 list_add(&new->list, &mtd_partitions);
609 mutex_unlock(&mtd_partitions_mutex);
610
611 ret = add_mtd_device(&new->mtd);
612 if (ret)
613 goto err_remove_part;
614
615 mtd_add_partition_attrs(new);
616
617 return 0;
618
619err_remove_part:
620 mutex_lock(&mtd_partitions_mutex);
621 list_del(&new->list);
622 mutex_unlock(&mtd_partitions_mutex);
623
624 free_partition(new);
625
626 return ret;
627}
628EXPORT_SYMBOL_GPL(mtd_add_partition);
629
630/**
631 * __mtd_del_partition - delete MTD partition
632 *
633 * @priv: internal MTD struct for partition to be deleted
634 *
635 * This function must be called with the partitions mutex locked.
636 */
637static int __mtd_del_partition(struct mtd_part *priv)
638{
639 struct mtd_part *child, *next;
640 int err;
641
642 list_for_each_entry_safe(child, next, &mtd_partitions, list) {
643 if (child->parent == &priv->mtd) {
644 err = __mtd_del_partition(child);
645 if (err)
646 return err;
647 }
648 }
649
650 sysfs_remove_files(&priv->mtd.dev.kobj, mtd_partition_attrs);
651
652 err = del_mtd_device(&priv->mtd);
653 if (err)
654 return err;
655
656 list_del(&priv->list);
657 free_partition(priv);
658
659 return 0;
660}
661
662/*
663 * This function unregisters and destroy all slave MTD objects which are
664 * attached to the given MTD object.
665 */
666int del_mtd_partitions(struct mtd_info *mtd)
667{
668 struct mtd_part *slave, *next;
669 int ret, err = 0;
670
671 mutex_lock(&mtd_partitions_mutex);
672 list_for_each_entry_safe(slave, next, &mtd_partitions, list)
673 if (slave->parent == mtd) {
674 ret = __mtd_del_partition(slave);
675 if (ret < 0)
676 err = ret;
677 }
678 mutex_unlock(&mtd_partitions_mutex);
679
680 return err;
681}
682
683int mtd_del_partition(struct mtd_info *mtd, int partno)
684{
685 struct mtd_part *slave, *next;
686 int ret = -EINVAL;
687
688 mutex_lock(&mtd_partitions_mutex);
689 list_for_each_entry_safe(slave, next, &mtd_partitions, list)
690 if ((slave->parent == mtd) &&
691 (slave->mtd.index == partno)) {
692 ret = __mtd_del_partition(slave);
693 break;
694 }
695 mutex_unlock(&mtd_partitions_mutex);
696
697 return ret;
698}
699EXPORT_SYMBOL_GPL(mtd_del_partition);
700
701/*
702 * This function, given a master MTD object and a partition table, creates
703 * and registers slave MTD objects which are bound to the master according to
704 * the partition definitions.
705 *
706 * For historical reasons, this function's caller only registers the master
707 * if the MTD_PARTITIONED_MASTER config option is set.
708 */
709
710int add_mtd_partitions(struct mtd_info *master,
711 const struct mtd_partition *parts,
712 int nbparts)
713{
714 struct mtd_part *slave;
715 uint64_t cur_offset = 0;
716 int i, ret;
717
718 printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
719
720 for (i = 0; i < nbparts; i++) {
721 slave = allocate_partition(master, parts + i, i, cur_offset);
722 if (IS_ERR(slave)) {
723 ret = PTR_ERR(slave);
724 goto err_del_partitions;
725 }
726
727 mutex_lock(&mtd_partitions_mutex);
728 list_add(&slave->list, &mtd_partitions);
729 mutex_unlock(&mtd_partitions_mutex);
730
731 ret = add_mtd_device(&slave->mtd);
732 if (ret) {
733 mutex_lock(&mtd_partitions_mutex);
734 list_del(&slave->list);
735 mutex_unlock(&mtd_partitions_mutex);
736
737 free_partition(slave);
738 goto err_del_partitions;
739 }
740
741 mtd_add_partition_attrs(slave);
742 /* Look for subpartitions */
743 parse_mtd_partitions(&slave->mtd, parts[i].types, NULL);
744
745 cur_offset = slave->offset + slave->mtd.size;
746 }
747
748 return 0;
749
750err_del_partitions:
751 del_mtd_partitions(master);
752
753 return ret;
754}
755
756static DEFINE_SPINLOCK(part_parser_lock);
757static LIST_HEAD(part_parsers);
758
759static struct mtd_part_parser *mtd_part_parser_get(const char *name)
760{
761 struct mtd_part_parser *p, *ret = NULL;
762
763 spin_lock(&part_parser_lock);
764
765 list_for_each_entry(p, &part_parsers, list)
766 if (!strcmp(p->name, name) && try_module_get(p->owner)) {
767 ret = p;
768 break;
769 }
770
771 spin_unlock(&part_parser_lock);
772
773 return ret;
774}
775
776static inline void mtd_part_parser_put(const struct mtd_part_parser *p)
777{
778 module_put(p->owner);
779}
780
781/*
782 * Many partition parsers just expected the core to kfree() all their data in
783 * one chunk. Do that by default.
784 */
785static void mtd_part_parser_cleanup_default(const struct mtd_partition *pparts,
786 int nr_parts)
787{
788 kfree(pparts);
789}
790
791int __register_mtd_parser(struct mtd_part_parser *p, struct module *owner)
792{
793 p->owner = owner;
794
795 if (!p->cleanup)
796 p->cleanup = &mtd_part_parser_cleanup_default;
797
798 spin_lock(&part_parser_lock);
799 list_add(&p->list, &part_parsers);
800 spin_unlock(&part_parser_lock);
801
802 return 0;
803}
804EXPORT_SYMBOL_GPL(__register_mtd_parser);
805
806void deregister_mtd_parser(struct mtd_part_parser *p)
807{
808 spin_lock(&part_parser_lock);
809 list_del(&p->list);
810 spin_unlock(&part_parser_lock);
811}
812EXPORT_SYMBOL_GPL(deregister_mtd_parser);
813
814/*
815 * Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
816 * are changing this array!
817 */
818static const char * const default_mtd_part_types[] = {
819 "cmdlinepart",
820 "ofpart",
821 NULL
822};
823
824/* Check DT only when looking for subpartitions. */
825static const char * const default_subpartition_types[] = {
826 "ofpart",
827 NULL
828};
829
830static int mtd_part_do_parse(struct mtd_part_parser *parser,
831 struct mtd_info *master,
832 struct mtd_partitions *pparts,
833 struct mtd_part_parser_data *data)
834{
835 int ret;
836
837 ret = (*parser->parse_fn)(master, &pparts->parts, data);
838 pr_debug("%s: parser %s: %i\n", master->name, parser->name, ret);
839 if (ret <= 0)
840 return ret;
841
842 pr_notice("%d %s partitions found on MTD device %s\n", ret,
843 parser->name, master->name);
844
845 pparts->nr_parts = ret;
846 pparts->parser = parser;
847
848 return ret;
849}
850
851/**
852 * mtd_part_get_compatible_parser - find MTD parser by a compatible string
853 *
854 * @compat: compatible string describing partitions in a device tree
855 *
856 * MTD parsers can specify supported partitions by providing a table of
857 * compatibility strings. This function finds a parser that advertises support
858 * for a passed value of "compatible".
859 */
860static struct mtd_part_parser *mtd_part_get_compatible_parser(const char *compat)
861{
862 struct mtd_part_parser *p, *ret = NULL;
863
864 spin_lock(&part_parser_lock);
865
866 list_for_each_entry(p, &part_parsers, list) {
867 const struct of_device_id *matches;
868
869 matches = p->of_match_table;
870 if (!matches)
871 continue;
872
873 for (; matches->compatible[0]; matches++) {
874 if (!strcmp(matches->compatible, compat) &&
875 try_module_get(p->owner)) {
876 ret = p;
877 break;
878 }
879 }
880
881 if (ret)
882 break;
883 }
884
885 spin_unlock(&part_parser_lock);
886
887 return ret;
888}
889
890static int mtd_part_of_parse(struct mtd_info *master,
891 struct mtd_partitions *pparts)
892{
893 struct mtd_part_parser *parser;
894 struct device_node *np;
895 struct property *prop;
896 const char *compat;
897 const char *fixed = "fixed-partitions";
898 int ret, err = 0;
899
900 np = mtd_get_of_node(master);
901 if (mtd_is_partition(master))
902 of_node_get(np);
903 else
904 np = of_get_child_by_name(np, "partitions");
905
906 of_property_for_each_string(np, "compatible", prop, compat) {
907 parser = mtd_part_get_compatible_parser(compat);
908 if (!parser)
909 continue;
910 ret = mtd_part_do_parse(parser, master, pparts, NULL);
911 if (ret > 0) {
912 of_node_put(np);
913 return ret;
914 }
915 mtd_part_parser_put(parser);
916 if (ret < 0 && !err)
917 err = ret;
918 }
919 of_node_put(np);
920
921 /*
922 * For backward compatibility we have to try the "fixed-partitions"
923 * parser. It supports old DT format with partitions specified as a
924 * direct subnodes of a flash device DT node without any compatibility
925 * specified we could match.
926 */
927 parser = mtd_part_parser_get(fixed);
928 if (!parser && !request_module("%s", fixed))
929 parser = mtd_part_parser_get(fixed);
930 if (parser) {
931 ret = mtd_part_do_parse(parser, master, pparts, NULL);
932 if (ret > 0)
933 return ret;
934 mtd_part_parser_put(parser);
935 if (ret < 0 && !err)
936 err = ret;
937 }
938
939 return err;
940}
941
942/**
943 * parse_mtd_partitions - parse and register MTD partitions
944 *
945 * @master: the master partition (describes whole MTD device)
946 * @types: names of partition parsers to try or %NULL
947 * @data: MTD partition parser-specific data
948 *
949 * This function tries to find & register partitions on MTD device @master. It
950 * uses MTD partition parsers, specified in @types. However, if @types is %NULL,
951 * then the default list of parsers is used. The default list contains only the
952 * "cmdlinepart" and "ofpart" parsers ATM.
953 * Note: If there are more then one parser in @types, the kernel only takes the
954 * partitions parsed out by the first parser.
955 *
956 * This function may return:
957 * o a negative error code in case of failure
958 * o number of found partitions otherwise
959 */
960int parse_mtd_partitions(struct mtd_info *master, const char *const *types,
961 struct mtd_part_parser_data *data)
962{
963 struct mtd_partitions pparts = { };
964 struct mtd_part_parser *parser;
965 int ret, err = 0;
966
967 if (!types)
968 types = mtd_is_partition(master) ? default_subpartition_types :
969 default_mtd_part_types;
970
971 for ( ; *types; types++) {
972 /*
973 * ofpart is a special type that means OF partitioning info
974 * should be used. It requires a bit different logic so it is
975 * handled in a separated function.
976 */
977 if (!strcmp(*types, "ofpart")) {
978 ret = mtd_part_of_parse(master, &pparts);
979 } else {
980 pr_debug("%s: parsing partitions %s\n", master->name,
981 *types);
982 parser = mtd_part_parser_get(*types);
983 if (!parser && !request_module("%s", *types))
984 parser = mtd_part_parser_get(*types);
985 pr_debug("%s: got parser %s\n", master->name,
986 parser ? parser->name : NULL);
987 if (!parser)
988 continue;
989 ret = mtd_part_do_parse(parser, master, &pparts, data);
990 if (ret <= 0)
991 mtd_part_parser_put(parser);
992 }
993 /* Found partitions! */
994 if (ret > 0) {
995 err = add_mtd_partitions(master, pparts.parts,
996 pparts.nr_parts);
997 mtd_part_parser_cleanup(&pparts);
998 return err ? err : pparts.nr_parts;
999 }
1000 /*
1001 * Stash the first error we see; only report it if no parser
1002 * succeeds
1003 */
1004 if (ret < 0 && !err)
1005 err = ret;
1006 }
1007 return err;
1008}
1009
1010void mtd_part_parser_cleanup(struct mtd_partitions *parts)
1011{
1012 const struct mtd_part_parser *parser;
1013
1014 if (!parts)
1015 return;
1016
1017 parser = parts->parser;
1018 if (parser) {
1019 if (parser->cleanup)
1020 parser->cleanup(parts->parts, parts->nr_parts);
1021
1022 mtd_part_parser_put(parser);
1023 }
1024}
1025
1026int mtd_is_partition(const struct mtd_info *mtd)
1027{
1028 struct mtd_part *part;
1029 int ispart = 0;
1030
1031 mutex_lock(&mtd_partitions_mutex);
1032 list_for_each_entry(part, &mtd_partitions, list)
1033 if (&part->mtd == mtd) {
1034 ispart = 1;
1035 break;
1036 }
1037 mutex_unlock(&mtd_partitions_mutex);
1038
1039 return ispart;
1040}
1041EXPORT_SYMBOL_GPL(mtd_is_partition);
1042
1043/* Returns the size of the entire flash chip */
1044uint64_t mtd_get_device_size(const struct mtd_info *mtd)
1045{
1046 if (!mtd_is_partition(mtd))
1047 return mtd->size;
1048
1049 return mtd_get_device_size(mtd_to_part(mtd)->parent);
1050}
1051EXPORT_SYMBOL_GPL(mtd_get_device_size);
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
35static struct mtd_info *allocate_partition(struct mtd_info *parent,
36 const struct mtd_partition *part,
37 int partno, uint64_t cur_offset)
38{
39 struct mtd_info *master = mtd_get_master(parent);
40 int wr_alignment = (parent->flags & MTD_NO_ERASE) ?
41 master->writesize : master->erasesize;
42 u64 parent_size = mtd_is_partition(parent) ?
43 parent->part.size : parent->size;
44 struct mtd_info *child;
45 u32 remainder;
46 char *name;
47 u64 tmp;
48
49 /* allocate the partition structure */
50 child = kzalloc(sizeof(*child), GFP_KERNEL);
51 name = kstrdup(part->name, GFP_KERNEL);
52 if (!name || !child) {
53 printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
54 parent->name);
55 kfree(name);
56 kfree(child);
57 return ERR_PTR(-ENOMEM);
58 }
59
60 /* set up the MTD object for this partition */
61 child->type = parent->type;
62 child->part.flags = parent->flags & ~part->mask_flags;
63 child->part.flags |= part->add_flags;
64 child->flags = child->part.flags;
65 child->part.size = part->size;
66 child->writesize = parent->writesize;
67 child->writebufsize = parent->writebufsize;
68 child->oobsize = parent->oobsize;
69 child->oobavail = parent->oobavail;
70 child->subpage_sft = parent->subpage_sft;
71
72 child->name = name;
73 child->owner = parent->owner;
74
75 /* NOTE: Historically, we didn't arrange MTDs as a tree out of
76 * concern for showing the same data in multiple partitions.
77 * However, it is very useful to have the master node present,
78 * so the MTD_PARTITIONED_MASTER option allows that. The master
79 * will have device nodes etc only if this is set, so make the
80 * parent conditional on that option. Note, this is a way to
81 * distinguish between the parent and its partitions in sysfs.
82 */
83 child->dev.parent = IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) || mtd_is_partition(parent) ?
84 &parent->dev : parent->dev.parent;
85 child->dev.of_node = part->of_node;
86 child->parent = parent;
87 child->part.offset = part->offset;
88 INIT_LIST_HEAD(&child->partitions);
89
90 if (child->part.offset == MTDPART_OFS_APPEND)
91 child->part.offset = cur_offset;
92 if (child->part.offset == MTDPART_OFS_NXTBLK) {
93 tmp = cur_offset;
94 child->part.offset = cur_offset;
95 remainder = do_div(tmp, wr_alignment);
96 if (remainder) {
97 child->part.offset += wr_alignment - remainder;
98 printk(KERN_NOTICE "Moving partition %d: "
99 "0x%012llx -> 0x%012llx\n", partno,
100 (unsigned long long)cur_offset,
101 child->part.offset);
102 }
103 }
104 if (child->part.offset == MTDPART_OFS_RETAIN) {
105 child->part.offset = cur_offset;
106 if (parent_size - child->part.offset >= child->part.size) {
107 child->part.size = parent_size - child->part.offset -
108 child->part.size;
109 } else {
110 printk(KERN_ERR "mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n",
111 part->name, parent_size - child->part.offset,
112 child->part.size);
113 /* register to preserve ordering */
114 goto out_register;
115 }
116 }
117 if (child->part.size == MTDPART_SIZ_FULL)
118 child->part.size = parent_size - child->part.offset;
119
120 printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n",
121 child->part.offset, child->part.offset + child->part.size,
122 child->name);
123
124 /* let's do some sanity checks */
125 if (child->part.offset >= parent_size) {
126 /* let's register it anyway to preserve ordering */
127 child->part.offset = 0;
128 child->part.size = 0;
129
130 /* Initialize ->erasesize to make add_mtd_device() happy. */
131 child->erasesize = parent->erasesize;
132 printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
133 part->name);
134 goto out_register;
135 }
136 if (child->part.offset + child->part.size > parent->size) {
137 child->part.size = parent_size - child->part.offset;
138 printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
139 part->name, parent->name, child->part.size);
140 }
141
142 if (parent->numeraseregions > 1) {
143 /* Deal with variable erase size stuff */
144 int i, max = parent->numeraseregions;
145 u64 end = child->part.offset + child->part.size;
146 struct mtd_erase_region_info *regions = parent->eraseregions;
147
148 /* Find the first erase regions which is part of this
149 * partition. */
150 for (i = 0; i < max && regions[i].offset <= child->part.offset;
151 i++)
152 ;
153 /* The loop searched for the region _behind_ the first one */
154 if (i > 0)
155 i--;
156
157 /* Pick biggest erasesize */
158 for (; i < max && regions[i].offset < end; i++) {
159 if (child->erasesize < regions[i].erasesize)
160 child->erasesize = regions[i].erasesize;
161 }
162 BUG_ON(child->erasesize == 0);
163 } else {
164 /* Single erase size */
165 child->erasesize = master->erasesize;
166 }
167
168 /*
169 * Child erasesize might differ from the parent one if the parent
170 * exposes several regions with different erasesize. Adjust
171 * wr_alignment accordingly.
172 */
173 if (!(child->flags & MTD_NO_ERASE))
174 wr_alignment = child->erasesize;
175
176 tmp = mtd_get_master_ofs(child, 0);
177 remainder = do_div(tmp, wr_alignment);
178 if ((child->flags & MTD_WRITEABLE) && remainder) {
179 /* Doesn't start on a boundary of major erase size */
180 /* FIXME: Let it be writable if it is on a boundary of
181 * _minor_ erase size though */
182 child->flags &= ~MTD_WRITEABLE;
183 printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase/write block boundary -- force read-only\n",
184 part->name);
185 }
186
187 tmp = mtd_get_master_ofs(child, 0) + child->part.size;
188 remainder = do_div(tmp, wr_alignment);
189 if ((child->flags & MTD_WRITEABLE) && remainder) {
190 child->flags &= ~MTD_WRITEABLE;
191 printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase/write block -- force read-only\n",
192 part->name);
193 }
194
195 child->size = child->part.size;
196 child->ecc_step_size = parent->ecc_step_size;
197 child->ecc_strength = parent->ecc_strength;
198 child->bitflip_threshold = parent->bitflip_threshold;
199
200 if (master->_block_isbad) {
201 uint64_t offs = 0;
202
203 while (offs < child->part.size) {
204 if (mtd_block_isreserved(child, offs))
205 child->ecc_stats.bbtblocks++;
206 else if (mtd_block_isbad(child, offs))
207 child->ecc_stats.badblocks++;
208 offs += child->erasesize;
209 }
210 }
211
212out_register:
213 return child;
214}
215
216static ssize_t offset_show(struct device *dev,
217 struct device_attribute *attr, char *buf)
218{
219 struct mtd_info *mtd = dev_get_drvdata(dev);
220
221 return sysfs_emit(buf, "%lld\n", mtd->part.offset);
222}
223static DEVICE_ATTR_RO(offset); /* mtd partition offset */
224
225static const struct attribute *mtd_partition_attrs[] = {
226 &dev_attr_offset.attr,
227 NULL
228};
229
230static int mtd_add_partition_attrs(struct mtd_info *new)
231{
232 int ret = sysfs_create_files(&new->dev.kobj, mtd_partition_attrs);
233 if (ret)
234 printk(KERN_WARNING
235 "mtd: failed to create partition attrs, err=%d\n", ret);
236 return ret;
237}
238
239int mtd_add_partition(struct mtd_info *parent, const char *name,
240 long long offset, long long length)
241{
242 struct mtd_info *master = mtd_get_master(parent);
243 u64 parent_size = mtd_is_partition(parent) ?
244 parent->part.size : parent->size;
245 struct mtd_partition part;
246 struct mtd_info *child;
247 int ret = 0;
248
249 /* the direct offset is expected */
250 if (offset == MTDPART_OFS_APPEND ||
251 offset == MTDPART_OFS_NXTBLK)
252 return -EINVAL;
253
254 if (length == MTDPART_SIZ_FULL)
255 length = parent_size - offset;
256
257 if (length <= 0)
258 return -EINVAL;
259
260 memset(&part, 0, sizeof(part));
261 part.name = name;
262 part.size = length;
263 part.offset = offset;
264
265 child = allocate_partition(parent, &part, -1, offset);
266 if (IS_ERR(child))
267 return PTR_ERR(child);
268
269 mutex_lock(&master->master.partitions_lock);
270 list_add_tail(&child->part.node, &parent->partitions);
271 mutex_unlock(&master->master.partitions_lock);
272
273 ret = add_mtd_device(child);
274 if (ret)
275 goto err_remove_part;
276
277 mtd_add_partition_attrs(child);
278
279 return 0;
280
281err_remove_part:
282 mutex_lock(&master->master.partitions_lock);
283 list_del(&child->part.node);
284 mutex_unlock(&master->master.partitions_lock);
285
286 free_partition(child);
287
288 return ret;
289}
290EXPORT_SYMBOL_GPL(mtd_add_partition);
291
292/**
293 * __mtd_del_partition - delete MTD partition
294 *
295 * @mtd: MTD structure to be deleted
296 *
297 * This function must be called with the partitions mutex locked.
298 */
299static int __mtd_del_partition(struct mtd_info *mtd)
300{
301 struct mtd_info *child, *next;
302 int err;
303
304 list_for_each_entry_safe(child, next, &mtd->partitions, part.node) {
305 err = __mtd_del_partition(child);
306 if (err)
307 return err;
308 }
309
310 sysfs_remove_files(&mtd->dev.kobj, mtd_partition_attrs);
311
312 err = del_mtd_device(mtd);
313 if (err)
314 return err;
315
316 list_del(&mtd->part.node);
317 free_partition(mtd);
318
319 return 0;
320}
321
322/*
323 * This function unregisters and destroy all slave MTD objects which are
324 * attached to the given MTD object, recursively.
325 */
326static int __del_mtd_partitions(struct mtd_info *mtd)
327{
328 struct mtd_info *child, *next;
329 LIST_HEAD(tmp_list);
330 int ret, err = 0;
331
332 list_for_each_entry_safe(child, next, &mtd->partitions, part.node) {
333 if (mtd_has_partitions(child))
334 __del_mtd_partitions(child);
335
336 pr_info("Deleting %s MTD partition\n", child->name);
337 ret = del_mtd_device(child);
338 if (ret < 0) {
339 pr_err("Error when deleting partition \"%s\" (%d)\n",
340 child->name, ret);
341 err = ret;
342 continue;
343 }
344
345 list_del(&child->part.node);
346 free_partition(child);
347 }
348
349 return err;
350}
351
352int del_mtd_partitions(struct mtd_info *mtd)
353{
354 struct mtd_info *master = mtd_get_master(mtd);
355 int ret;
356
357 pr_info("Deleting MTD partitions on \"%s\":\n", mtd->name);
358
359 mutex_lock(&master->master.partitions_lock);
360 ret = __del_mtd_partitions(mtd);
361 mutex_unlock(&master->master.partitions_lock);
362
363 return ret;
364}
365
366int mtd_del_partition(struct mtd_info *mtd, int partno)
367{
368 struct mtd_info *child, *master = mtd_get_master(mtd);
369 int ret = -EINVAL;
370
371 mutex_lock(&master->master.partitions_lock);
372 list_for_each_entry(child, &mtd->partitions, part.node) {
373 if (child->index == partno) {
374 ret = __mtd_del_partition(child);
375 break;
376 }
377 }
378 mutex_unlock(&master->master.partitions_lock);
379
380 return ret;
381}
382EXPORT_SYMBOL_GPL(mtd_del_partition);
383
384/*
385 * This function, given a parent MTD object and a partition table, creates
386 * and registers the child MTD objects which are bound to the parent according
387 * to the partition definitions.
388 *
389 * For historical reasons, this function's caller only registers the parent
390 * if the MTD_PARTITIONED_MASTER config option is set.
391 */
392
393int add_mtd_partitions(struct mtd_info *parent,
394 const struct mtd_partition *parts,
395 int nbparts)
396{
397 struct mtd_info *child, *master = mtd_get_master(parent);
398 uint64_t cur_offset = 0;
399 int i, ret;
400
401 printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n",
402 nbparts, parent->name);
403
404 for (i = 0; i < nbparts; i++) {
405 child = allocate_partition(parent, parts + i, i, cur_offset);
406 if (IS_ERR(child)) {
407 ret = PTR_ERR(child);
408 goto err_del_partitions;
409 }
410
411 mutex_lock(&master->master.partitions_lock);
412 list_add_tail(&child->part.node, &parent->partitions);
413 mutex_unlock(&master->master.partitions_lock);
414
415 ret = add_mtd_device(child);
416 if (ret) {
417 mutex_lock(&master->master.partitions_lock);
418 list_del(&child->part.node);
419 mutex_unlock(&master->master.partitions_lock);
420
421 free_partition(child);
422 goto err_del_partitions;
423 }
424
425 mtd_add_partition_attrs(child);
426
427 /* Look for subpartitions */
428 parse_mtd_partitions(child, parts[i].types, NULL);
429
430 cur_offset = child->part.offset + child->part.size;
431 }
432
433 return 0;
434
435err_del_partitions:
436 del_mtd_partitions(master);
437
438 return ret;
439}
440
441static DEFINE_SPINLOCK(part_parser_lock);
442static LIST_HEAD(part_parsers);
443
444static struct mtd_part_parser *mtd_part_parser_get(const char *name)
445{
446 struct mtd_part_parser *p, *ret = NULL;
447
448 spin_lock(&part_parser_lock);
449
450 list_for_each_entry(p, &part_parsers, list)
451 if (!strcmp(p->name, name) && try_module_get(p->owner)) {
452 ret = p;
453 break;
454 }
455
456 spin_unlock(&part_parser_lock);
457
458 return ret;
459}
460
461static inline void mtd_part_parser_put(const struct mtd_part_parser *p)
462{
463 module_put(p->owner);
464}
465
466/*
467 * Many partition parsers just expected the core to kfree() all their data in
468 * one chunk. Do that by default.
469 */
470static void mtd_part_parser_cleanup_default(const struct mtd_partition *pparts,
471 int nr_parts)
472{
473 kfree(pparts);
474}
475
476int __register_mtd_parser(struct mtd_part_parser *p, struct module *owner)
477{
478 p->owner = owner;
479
480 if (!p->cleanup)
481 p->cleanup = &mtd_part_parser_cleanup_default;
482
483 spin_lock(&part_parser_lock);
484 list_add(&p->list, &part_parsers);
485 spin_unlock(&part_parser_lock);
486
487 return 0;
488}
489EXPORT_SYMBOL_GPL(__register_mtd_parser);
490
491void deregister_mtd_parser(struct mtd_part_parser *p)
492{
493 spin_lock(&part_parser_lock);
494 list_del(&p->list);
495 spin_unlock(&part_parser_lock);
496}
497EXPORT_SYMBOL_GPL(deregister_mtd_parser);
498
499/*
500 * Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
501 * are changing this array!
502 */
503static const char * const default_mtd_part_types[] = {
504 "cmdlinepart",
505 "ofpart",
506 NULL
507};
508
509/* Check DT only when looking for subpartitions. */
510static const char * const default_subpartition_types[] = {
511 "ofpart",
512 NULL
513};
514
515static int mtd_part_do_parse(struct mtd_part_parser *parser,
516 struct mtd_info *master,
517 struct mtd_partitions *pparts,
518 struct mtd_part_parser_data *data)
519{
520 int ret;
521
522 ret = (*parser->parse_fn)(master, &pparts->parts, data);
523 pr_debug("%s: parser %s: %i\n", master->name, parser->name, ret);
524 if (ret <= 0)
525 return ret;
526
527 pr_notice("%d %s partitions found on MTD device %s\n", ret,
528 parser->name, master->name);
529
530 pparts->nr_parts = ret;
531 pparts->parser = parser;
532
533 return ret;
534}
535
536/**
537 * mtd_part_get_compatible_parser - find MTD parser by a compatible string
538 *
539 * @compat: compatible string describing partitions in a device tree
540 *
541 * MTD parsers can specify supported partitions by providing a table of
542 * compatibility strings. This function finds a parser that advertises support
543 * for a passed value of "compatible".
544 */
545static struct mtd_part_parser *mtd_part_get_compatible_parser(const char *compat)
546{
547 struct mtd_part_parser *p, *ret = NULL;
548
549 spin_lock(&part_parser_lock);
550
551 list_for_each_entry(p, &part_parsers, list) {
552 const struct of_device_id *matches;
553
554 matches = p->of_match_table;
555 if (!matches)
556 continue;
557
558 for (; matches->compatible[0]; matches++) {
559 if (!strcmp(matches->compatible, compat) &&
560 try_module_get(p->owner)) {
561 ret = p;
562 break;
563 }
564 }
565
566 if (ret)
567 break;
568 }
569
570 spin_unlock(&part_parser_lock);
571
572 return ret;
573}
574
575static int mtd_part_of_parse(struct mtd_info *master,
576 struct mtd_partitions *pparts)
577{
578 struct mtd_part_parser *parser;
579 struct device_node *np;
580 struct property *prop;
581 struct device *dev;
582 const char *compat;
583 const char *fixed = "fixed-partitions";
584 int ret, err = 0;
585
586 dev = &master->dev;
587 /* Use parent device (controller) if the top level MTD is not registered */
588 if (!IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) && !mtd_is_partition(master))
589 dev = master->dev.parent;
590
591 np = mtd_get_of_node(master);
592 if (mtd_is_partition(master))
593 of_node_get(np);
594 else
595 np = of_get_child_by_name(np, "partitions");
596
597 of_property_for_each_string(np, "compatible", prop, compat) {
598 parser = mtd_part_get_compatible_parser(compat);
599 if (!parser)
600 continue;
601 ret = mtd_part_do_parse(parser, master, pparts, NULL);
602 if (ret > 0) {
603 of_platform_populate(np, NULL, NULL, dev);
604 of_node_put(np);
605 return ret;
606 }
607 mtd_part_parser_put(parser);
608 if (ret < 0 && !err)
609 err = ret;
610 }
611 of_platform_populate(np, NULL, NULL, dev);
612 of_node_put(np);
613
614 /*
615 * For backward compatibility we have to try the "fixed-partitions"
616 * parser. It supports old DT format with partitions specified as a
617 * direct subnodes of a flash device DT node without any compatibility
618 * specified we could match.
619 */
620 parser = mtd_part_parser_get(fixed);
621 if (!parser && !request_module("%s", fixed))
622 parser = mtd_part_parser_get(fixed);
623 if (parser) {
624 ret = mtd_part_do_parse(parser, master, pparts, NULL);
625 if (ret > 0)
626 return ret;
627 mtd_part_parser_put(parser);
628 if (ret < 0 && !err)
629 err = ret;
630 }
631
632 return err;
633}
634
635/**
636 * parse_mtd_partitions - parse and register MTD partitions
637 *
638 * @master: the master partition (describes whole MTD device)
639 * @types: names of partition parsers to try or %NULL
640 * @data: MTD partition parser-specific data
641 *
642 * This function tries to find & register partitions on MTD device @master. It
643 * uses MTD partition parsers, specified in @types. However, if @types is %NULL,
644 * then the default list of parsers is used. The default list contains only the
645 * "cmdlinepart" and "ofpart" parsers ATM.
646 * Note: If there are more then one parser in @types, the kernel only takes the
647 * partitions parsed out by the first parser.
648 *
649 * This function may return:
650 * o a negative error code in case of failure
651 * o number of found partitions otherwise
652 */
653int parse_mtd_partitions(struct mtd_info *master, const char *const *types,
654 struct mtd_part_parser_data *data)
655{
656 struct mtd_partitions pparts = { };
657 struct mtd_part_parser *parser;
658 int ret, err = 0;
659
660 if (!types)
661 types = mtd_is_partition(master) ? default_subpartition_types :
662 default_mtd_part_types;
663
664 for ( ; *types; types++) {
665 /*
666 * ofpart is a special type that means OF partitioning info
667 * should be used. It requires a bit different logic so it is
668 * handled in a separated function.
669 */
670 if (!strcmp(*types, "ofpart")) {
671 ret = mtd_part_of_parse(master, &pparts);
672 } else {
673 pr_debug("%s: parsing partitions %s\n", master->name,
674 *types);
675 parser = mtd_part_parser_get(*types);
676 if (!parser && !request_module("%s", *types))
677 parser = mtd_part_parser_get(*types);
678 pr_debug("%s: got parser %s\n", master->name,
679 parser ? parser->name : NULL);
680 if (!parser)
681 continue;
682 ret = mtd_part_do_parse(parser, master, &pparts, data);
683 if (ret <= 0)
684 mtd_part_parser_put(parser);
685 }
686 /* Found partitions! */
687 if (ret > 0) {
688 err = add_mtd_partitions(master, pparts.parts,
689 pparts.nr_parts);
690 mtd_part_parser_cleanup(&pparts);
691 return err ? err : pparts.nr_parts;
692 }
693 /*
694 * Stash the first error we see; only report it if no parser
695 * succeeds
696 */
697 if (ret < 0 && !err)
698 err = ret;
699 }
700 return err;
701}
702
703void mtd_part_parser_cleanup(struct mtd_partitions *parts)
704{
705 const struct mtd_part_parser *parser;
706
707 if (!parts)
708 return;
709
710 parser = parts->parser;
711 if (parser) {
712 if (parser->cleanup)
713 parser->cleanup(parts->parts, parts->nr_parts);
714
715 mtd_part_parser_put(parser);
716 }
717}
718
719/* Returns the size of the entire flash chip */
720uint64_t mtd_get_device_size(const struct mtd_info *mtd)
721{
722 struct mtd_info *master = mtd_get_master((struct mtd_info *)mtd);
723
724 return master->size;
725}
726EXPORT_SYMBOL_GPL(mtd_get_device_size);