Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux...
[linux-2.6.git] / drivers / mtd / mtdpart.c
1 /*
2  * Simple MTD partitioning layer
3  *
4  * (C) 2000 Nicolas Pitre <nico@fluxnic.net>
5  *
6  * This code is GPL
7  *
8  *      02-21-2002      Thomas Gleixner <gleixner@autronix.de>
9  *                      added support for read_oob, write_oob
10  */
11
12 #include <linux/module.h>
13 #include <linux/types.h>
14 #include <linux/kernel.h>
15 #include <linux/slab.h>
16 #include <linux/list.h>
17 #include <linux/kmod.h>
18 #include <linux/mtd/mtd.h>
19 #include <linux/mtd/partitions.h>
20 #include <linux/mtd/compatmac.h>
21
22 /* Our partition linked list */
23 static LIST_HEAD(mtd_partitions);
24
25 /* Our partition node structure */
26 struct mtd_part {
27         struct mtd_info mtd;
28         struct mtd_info *master;
29         uint64_t offset;
30         struct list_head list;
31 };
32
33 /*
34  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
35  * the pointer to that structure with this macro.
36  */
37 #define PART(x)  ((struct mtd_part *)(x))
38
39
40 /*
41  * MTD methods which simply translate the effective address and pass through
42  * to the _real_ device.
43  */
44
45 static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
46                 size_t *retlen, u_char *buf)
47 {
48         struct mtd_part *part = PART(mtd);
49         struct mtd_ecc_stats stats;
50         int res;
51
52         stats = part->master->ecc_stats;
53
54         if (from >= mtd->size)
55                 len = 0;
56         else if (from + len > mtd->size)
57                 len = mtd->size - from;
58         res = part->master->read(part->master, from + part->offset,
59                                    len, retlen, buf);
60         if (unlikely(res)) {
61                 if (res == -EUCLEAN)
62                         mtd->ecc_stats.corrected += part->master->ecc_stats.corrected - stats.corrected;
63                 if (res == -EBADMSG)
64                         mtd->ecc_stats.failed += part->master->ecc_stats.failed - stats.failed;
65         }
66         return res;
67 }
68
69 static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
70                 size_t *retlen, void **virt, resource_size_t *phys)
71 {
72         struct mtd_part *part = PART(mtd);
73         if (from >= mtd->size)
74                 len = 0;
75         else if (from + len > mtd->size)
76                 len = mtd->size - from;
77         return part->master->point (part->master, from + part->offset,
78                                     len, retlen, virt, phys);
79 }
80
81 static void part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
82 {
83         struct mtd_part *part = PART(mtd);
84
85         part->master->unpoint(part->master, from + part->offset, len);
86 }
87
88 static unsigned long part_get_unmapped_area(struct mtd_info *mtd,
89                                             unsigned long len,
90                                             unsigned long offset,
91                                             unsigned long flags)
92 {
93         struct mtd_part *part = PART(mtd);
94
95         offset += part->offset;
96         return part->master->get_unmapped_area(part->master, len, offset,
97                                                flags);
98 }
99
100 static int part_read_oob(struct mtd_info *mtd, loff_t from,
101                 struct mtd_oob_ops *ops)
102 {
103         struct mtd_part *part = PART(mtd);
104         int res;
105
106         if (from >= mtd->size)
107                 return -EINVAL;
108         if (ops->datbuf && from + ops->len > mtd->size)
109                 return -EINVAL;
110         res = part->master->read_oob(part->master, from + part->offset, ops);
111
112         if (unlikely(res)) {
113                 if (res == -EUCLEAN)
114                         mtd->ecc_stats.corrected++;
115                 if (res == -EBADMSG)
116                         mtd->ecc_stats.failed++;
117         }
118         return res;
119 }
120
121 static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
122                 size_t len, size_t *retlen, u_char *buf)
123 {
124         struct mtd_part *part = PART(mtd);
125         return part->master->read_user_prot_reg(part->master, from,
126                                         len, retlen, buf);
127 }
128
129 static int part_get_user_prot_info(struct mtd_info *mtd,
130                 struct otp_info *buf, size_t len)
131 {
132         struct mtd_part *part = PART(mtd);
133         return part->master->get_user_prot_info(part->master, buf, len);
134 }
135
136 static int part_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
137                 size_t len, size_t *retlen, u_char *buf)
138 {
139         struct mtd_part *part = PART(mtd);
140         return part->master->read_fact_prot_reg(part->master, from,
141                                         len, retlen, buf);
142 }
143
144 static int part_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
145                 size_t len)
146 {
147         struct mtd_part *part = PART(mtd);
148         return part->master->get_fact_prot_info(part->master, buf, len);
149 }
150
151 static int part_write(struct mtd_info *mtd, loff_t to, size_t len,
152                 size_t *retlen, const u_char *buf)
153 {
154         struct mtd_part *part = PART(mtd);
155         if (!(mtd->flags & MTD_WRITEABLE))
156                 return -EROFS;
157         if (to >= mtd->size)
158                 len = 0;
159         else if (to + len > mtd->size)
160                 len = mtd->size - to;
161         return part->master->write(part->master, to + part->offset,
162                                     len, retlen, buf);
163 }
164
165 static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
166                 size_t *retlen, const u_char *buf)
167 {
168         struct mtd_part *part = PART(mtd);
169         if (!(mtd->flags & MTD_WRITEABLE))
170                 return -EROFS;
171         if (to >= mtd->size)
172                 len = 0;
173         else if (to + len > mtd->size)
174                 len = mtd->size - to;
175         return part->master->panic_write(part->master, to + part->offset,
176                                     len, retlen, buf);
177 }
178
179 static int part_write_oob(struct mtd_info *mtd, loff_t to,
180                 struct mtd_oob_ops *ops)
181 {
182         struct mtd_part *part = PART(mtd);
183
184         if (!(mtd->flags & MTD_WRITEABLE))
185                 return -EROFS;
186
187         if (to >= mtd->size)
188                 return -EINVAL;
189         if (ops->datbuf && to + ops->len > mtd->size)
190                 return -EINVAL;
191         return part->master->write_oob(part->master, to + part->offset, ops);
192 }
193
194 static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
195                 size_t len, size_t *retlen, u_char *buf)
196 {
197         struct mtd_part *part = PART(mtd);
198         return part->master->write_user_prot_reg(part->master, from,
199                                         len, retlen, buf);
200 }
201
202 static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
203                 size_t len)
204 {
205         struct mtd_part *part = PART(mtd);
206         return part->master->lock_user_prot_reg(part->master, from, len);
207 }
208
209 static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,
210                 unsigned long count, loff_t to, size_t *retlen)
211 {
212         struct mtd_part *part = PART(mtd);
213         if (!(mtd->flags & MTD_WRITEABLE))
214                 return -EROFS;
215         return part->master->writev(part->master, vecs, count,
216                                         to + part->offset, retlen);
217 }
218
219 static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
220 {
221         struct mtd_part *part = PART(mtd);
222         int ret;
223         if (!(mtd->flags & MTD_WRITEABLE))
224                 return -EROFS;
225         if (instr->addr >= mtd->size)
226                 return -EINVAL;
227         instr->addr += part->offset;
228         ret = part->master->erase(part->master, instr);
229         if (ret) {
230                 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
231                         instr->fail_addr -= part->offset;
232                 instr->addr -= part->offset;
233         }
234         return ret;
235 }
236
237 void mtd_erase_callback(struct erase_info *instr)
238 {
239         if (instr->mtd->erase == part_erase) {
240                 struct mtd_part *part = PART(instr->mtd);
241
242                 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
243                         instr->fail_addr -= part->offset;
244                 instr->addr -= part->offset;
245         }
246         if (instr->callback)
247                 instr->callback(instr);
248 }
249 EXPORT_SYMBOL_GPL(mtd_erase_callback);
250
251 static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
252 {
253         struct mtd_part *part = PART(mtd);
254         if ((len + ofs) > mtd->size)
255                 return -EINVAL;
256         return part->master->lock(part->master, ofs + part->offset, len);
257 }
258
259 static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
260 {
261         struct mtd_part *part = PART(mtd);
262         if ((len + ofs) > mtd->size)
263                 return -EINVAL;
264         return part->master->unlock(part->master, ofs + part->offset, len);
265 }
266
267 static void part_sync(struct mtd_info *mtd)
268 {
269         struct mtd_part *part = PART(mtd);
270         part->master->sync(part->master);
271 }
272
273 static int part_suspend(struct mtd_info *mtd)
274 {
275         struct mtd_part *part = PART(mtd);
276         return part->master->suspend(part->master);
277 }
278
279 static void part_resume(struct mtd_info *mtd)
280 {
281         struct mtd_part *part = PART(mtd);
282         part->master->resume(part->master);
283 }
284
285 static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
286 {
287         struct mtd_part *part = PART(mtd);
288         if (ofs >= mtd->size)
289                 return -EINVAL;
290         ofs += part->offset;
291         return part->master->block_isbad(part->master, ofs);
292 }
293
294 static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
295 {
296         struct mtd_part *part = PART(mtd);
297         int res;
298
299         if (!(mtd->flags & MTD_WRITEABLE))
300                 return -EROFS;
301         if (ofs >= mtd->size)
302                 return -EINVAL;
303         ofs += part->offset;
304         res = part->master->block_markbad(part->master, ofs);
305         if (!res)
306                 mtd->ecc_stats.badblocks++;
307         return res;
308 }
309
310 /*
311  * This function unregisters and destroy all slave MTD objects which are
312  * attached to the given master MTD object.
313  */
314
315 int del_mtd_partitions(struct mtd_info *master)
316 {
317         struct mtd_part *slave, *next;
318
319         list_for_each_entry_safe(slave, next, &mtd_partitions, list)
320                 if (slave->master == master) {
321                         list_del(&slave->list);
322                         del_mtd_device(&slave->mtd);
323                         kfree(slave);
324                 }
325
326         return 0;
327 }
328 EXPORT_SYMBOL(del_mtd_partitions);
329
330 static struct mtd_part *add_one_partition(struct mtd_info *master,
331                 const struct mtd_partition *part, int partno,
332                 uint64_t cur_offset)
333 {
334         struct mtd_part *slave;
335
336         /* allocate the partition structure */
337         slave = kzalloc(sizeof(*slave), GFP_KERNEL);
338         if (!slave) {
339                 printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
340                         master->name);
341                 del_mtd_partitions(master);
342                 return NULL;
343         }
344         list_add(&slave->list, &mtd_partitions);
345
346         /* set up the MTD object for this partition */
347         slave->mtd.type = master->type;
348         slave->mtd.flags = master->flags & ~part->mask_flags;
349         slave->mtd.size = part->size;
350         slave->mtd.writesize = master->writesize;
351         slave->mtd.oobsize = master->oobsize;
352         slave->mtd.oobavail = master->oobavail;
353         slave->mtd.subpage_sft = master->subpage_sft;
354
355         slave->mtd.name = part->name;
356         slave->mtd.owner = master->owner;
357         slave->mtd.backing_dev_info = master->backing_dev_info;
358
359         /* NOTE:  we don't arrange MTDs as a tree; it'd be error-prone
360          * to have the same data be in two different partitions.
361          */
362         slave->mtd.dev.parent = master->dev.parent;
363
364         slave->mtd.read = part_read;
365         slave->mtd.write = part_write;
366
367         if (master->panic_write)
368                 slave->mtd.panic_write = part_panic_write;
369
370         if (master->point && master->unpoint) {
371                 slave->mtd.point = part_point;
372                 slave->mtd.unpoint = part_unpoint;
373         }
374
375         if (master->get_unmapped_area)
376                 slave->mtd.get_unmapped_area = part_get_unmapped_area;
377         if (master->read_oob)
378                 slave->mtd.read_oob = part_read_oob;
379         if (master->write_oob)
380                 slave->mtd.write_oob = part_write_oob;
381         if (master->read_user_prot_reg)
382                 slave->mtd.read_user_prot_reg = part_read_user_prot_reg;
383         if (master->read_fact_prot_reg)
384                 slave->mtd.read_fact_prot_reg = part_read_fact_prot_reg;
385         if (master->write_user_prot_reg)
386                 slave->mtd.write_user_prot_reg = part_write_user_prot_reg;
387         if (master->lock_user_prot_reg)
388                 slave->mtd.lock_user_prot_reg = part_lock_user_prot_reg;
389         if (master->get_user_prot_info)
390                 slave->mtd.get_user_prot_info = part_get_user_prot_info;
391         if (master->get_fact_prot_info)
392                 slave->mtd.get_fact_prot_info = part_get_fact_prot_info;
393         if (master->sync)
394                 slave->mtd.sync = part_sync;
395         if (!partno && !master->dev.class && master->suspend && master->resume) {
396                         slave->mtd.suspend = part_suspend;
397                         slave->mtd.resume = part_resume;
398         }
399         if (master->writev)
400                 slave->mtd.writev = part_writev;
401         if (master->lock)
402                 slave->mtd.lock = part_lock;
403         if (master->unlock)
404                 slave->mtd.unlock = part_unlock;
405         if (master->block_isbad)
406                 slave->mtd.block_isbad = part_block_isbad;
407         if (master->block_markbad)
408                 slave->mtd.block_markbad = part_block_markbad;
409         slave->mtd.erase = part_erase;
410         slave->master = master;
411         slave->offset = part->offset;
412
413         if (slave->offset == MTDPART_OFS_APPEND)
414                 slave->offset = cur_offset;
415         if (slave->offset == MTDPART_OFS_NXTBLK) {
416                 slave->offset = cur_offset;
417                 if (mtd_mod_by_eb(cur_offset, master) != 0) {
418                         /* Round up to next erasesize */
419                         slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
420                         printk(KERN_NOTICE "Moving partition %d: "
421                                "0x%012llx -> 0x%012llx\n", partno,
422                                (unsigned long long)cur_offset, (unsigned long long)slave->offset);
423                 }
424         }
425         if (slave->mtd.size == MTDPART_SIZ_FULL)
426                 slave->mtd.size = master->size - slave->offset;
427
428         printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
429                 (unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
430
431         /* let's do some sanity checks */
432         if (slave->offset >= master->size) {
433                 /* let's register it anyway to preserve ordering */
434                 slave->offset = 0;
435                 slave->mtd.size = 0;
436                 printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
437                         part->name);
438                 goto out_register;
439         }
440         if (slave->offset + slave->mtd.size > master->size) {
441                 slave->mtd.size = master->size - slave->offset;
442                 printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
443                         part->name, master->name, (unsigned long long)slave->mtd.size);
444         }
445         if (master->numeraseregions > 1) {
446                 /* Deal with variable erase size stuff */
447                 int i, max = master->numeraseregions;
448                 u64 end = slave->offset + slave->mtd.size;
449                 struct mtd_erase_region_info *regions = master->eraseregions;
450
451                 /* Find the first erase regions which is part of this
452                  * partition. */
453                 for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
454                         ;
455                 /* The loop searched for the region _behind_ the first one */
456                 if (i > 0)
457                         i--;
458
459                 /* Pick biggest erasesize */
460                 for (; i < max && regions[i].offset < end; i++) {
461                         if (slave->mtd.erasesize < regions[i].erasesize) {
462                                 slave->mtd.erasesize = regions[i].erasesize;
463                         }
464                 }
465                 BUG_ON(slave->mtd.erasesize == 0);
466         } else {
467                 /* Single erase size */
468                 slave->mtd.erasesize = master->erasesize;
469         }
470
471         if ((slave->mtd.flags & MTD_WRITEABLE) &&
472             mtd_mod_by_eb(slave->offset, &slave->mtd)) {
473                 /* Doesn't start on a boundary of major erase size */
474                 /* FIXME: Let it be writable if it is on a boundary of
475                  * _minor_ erase size though */
476                 slave->mtd.flags &= ~MTD_WRITEABLE;
477                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
478                         part->name);
479         }
480         if ((slave->mtd.flags & MTD_WRITEABLE) &&
481             mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) {
482                 slave->mtd.flags &= ~MTD_WRITEABLE;
483                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
484                         part->name);
485         }
486
487         slave->mtd.ecclayout = master->ecclayout;
488         if (master->block_isbad) {
489                 uint64_t offs = 0;
490
491                 while (offs < slave->mtd.size) {
492                         if (master->block_isbad(master,
493                                                 offs + slave->offset))
494                                 slave->mtd.ecc_stats.badblocks++;
495                         offs += slave->mtd.erasesize;
496                 }
497         }
498
499 out_register:
500         /* register our partition */
501         add_mtd_device(&slave->mtd);
502
503         return slave;
504 }
505
506 /*
507  * This function, given a master MTD object and a partition table, creates
508  * and registers slave MTD objects which are bound to the master according to
509  * the partition definitions.
510  *
511  * We don't register the master, or expect the caller to have done so,
512  * for reasons of data integrity.
513  */
514
515 int add_mtd_partitions(struct mtd_info *master,
516                        const struct mtd_partition *parts,
517                        int nbparts)
518 {
519         struct mtd_part *slave;
520         uint64_t cur_offset = 0;
521         int i;
522
523         printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
524
525         for (i = 0; i < nbparts; i++) {
526                 slave = add_one_partition(master, parts + i, i, cur_offset);
527                 if (!slave)
528                         return -ENOMEM;
529                 cur_offset = slave->offset + slave->mtd.size;
530         }
531
532         return 0;
533 }
534 EXPORT_SYMBOL(add_mtd_partitions);
535
536 static DEFINE_SPINLOCK(part_parser_lock);
537 static LIST_HEAD(part_parsers);
538
539 static struct mtd_part_parser *get_partition_parser(const char *name)
540 {
541         struct mtd_part_parser *p, *ret = NULL;
542
543         spin_lock(&part_parser_lock);
544
545         list_for_each_entry(p, &part_parsers, list)
546                 if (!strcmp(p->name, name) && try_module_get(p->owner)) {
547                         ret = p;
548                         break;
549                 }
550
551         spin_unlock(&part_parser_lock);
552
553         return ret;
554 }
555
556 int register_mtd_parser(struct mtd_part_parser *p)
557 {
558         spin_lock(&part_parser_lock);
559         list_add(&p->list, &part_parsers);
560         spin_unlock(&part_parser_lock);
561
562         return 0;
563 }
564 EXPORT_SYMBOL_GPL(register_mtd_parser);
565
566 int deregister_mtd_parser(struct mtd_part_parser *p)
567 {
568         spin_lock(&part_parser_lock);
569         list_del(&p->list);
570         spin_unlock(&part_parser_lock);
571         return 0;
572 }
573 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
574
575 int parse_mtd_partitions(struct mtd_info *master, const char **types,
576                          struct mtd_partition **pparts, unsigned long origin)
577 {
578         struct mtd_part_parser *parser;
579         int ret = 0;
580
581         for ( ; ret <= 0 && *types; types++) {
582                 parser = get_partition_parser(*types);
583                 if (!parser && !request_module("%s", *types))
584                                 parser = get_partition_parser(*types);
585                 if (!parser) {
586                         printk(KERN_NOTICE "%s partition parsing not available\n",
587                                *types);
588                         continue;
589                 }
590                 ret = (*parser->parse_fn)(master, pparts, origin);
591                 if (ret > 0) {
592                         printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
593                                ret, parser->name, master->name);
594                 }
595                 put_partition_parser(parser);
596         }
597         return ret;
598 }
599 EXPORT_SYMBOL_GPL(parse_mtd_partitions);