Merge branch 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6
[linux-2.6] / drivers / mtd / mtdpart.c
1 /*
2  * Simple MTD partitioning layer
3  *
4  * (C) 2000 Nicolas Pitre <nico@cam.org>
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         int index;
31         struct list_head list;
32         int registered;
33 };
34
35 /*
36  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
37  * the pointer to that structure with this macro.
38  */
39 #define PART(x)  ((struct mtd_part *)(x))
40
41
42 /*
43  * MTD methods which simply translate the effective address and pass through
44  * to the _real_ device.
45  */
46
47 static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
48                 size_t *retlen, u_char *buf)
49 {
50         struct mtd_part *part = PART(mtd);
51         int res;
52
53         if (from >= mtd->size)
54                 len = 0;
55         else if (from + len > mtd->size)
56                 len = mtd->size - from;
57         res = part->master->read(part->master, from + part->offset,
58                                    len, retlen, buf);
59         if (unlikely(res)) {
60                 if (res == -EUCLEAN)
61                         mtd->ecc_stats.corrected++;
62                 if (res == -EBADMSG)
63                         mtd->ecc_stats.failed++;
64         }
65         return res;
66 }
67
68 static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
69                 size_t *retlen, void **virt, resource_size_t *phys)
70 {
71         struct mtd_part *part = PART(mtd);
72         if (from >= mtd->size)
73                 len = 0;
74         else if (from + len > mtd->size)
75                 len = mtd->size - from;
76         return part->master->point (part->master, from + part->offset,
77                                     len, retlen, virt, phys);
78 }
79
80 static void part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
81 {
82         struct mtd_part *part = PART(mtd);
83
84         part->master->unpoint(part->master, from + part->offset, len);
85 }
86
87 static int part_read_oob(struct mtd_info *mtd, loff_t from,
88                 struct mtd_oob_ops *ops)
89 {
90         struct mtd_part *part = PART(mtd);
91         int res;
92
93         if (from >= mtd->size)
94                 return -EINVAL;
95         if (ops->datbuf && from + ops->len > mtd->size)
96                 return -EINVAL;
97         res = part->master->read_oob(part->master, from + part->offset, ops);
98
99         if (unlikely(res)) {
100                 if (res == -EUCLEAN)
101                         mtd->ecc_stats.corrected++;
102                 if (res == -EBADMSG)
103                         mtd->ecc_stats.failed++;
104         }
105         return res;
106 }
107
108 static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
109                 size_t len, size_t *retlen, u_char *buf)
110 {
111         struct mtd_part *part = PART(mtd);
112         return part->master->read_user_prot_reg(part->master, from,
113                                         len, retlen, buf);
114 }
115
116 static int part_get_user_prot_info(struct mtd_info *mtd,
117                 struct otp_info *buf, size_t len)
118 {
119         struct mtd_part *part = PART(mtd);
120         return part->master->get_user_prot_info(part->master, buf, len);
121 }
122
123 static int part_read_fact_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 = PART(mtd);
127         return part->master->read_fact_prot_reg(part->master, from,
128                                         len, retlen, buf);
129 }
130
131 static int part_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
132                 size_t len)
133 {
134         struct mtd_part *part = PART(mtd);
135         return part->master->get_fact_prot_info(part->master, buf, len);
136 }
137
138 static int part_write(struct mtd_info *mtd, loff_t to, size_t len,
139                 size_t *retlen, const u_char *buf)
140 {
141         struct mtd_part *part = PART(mtd);
142         if (!(mtd->flags & MTD_WRITEABLE))
143                 return -EROFS;
144         if (to >= mtd->size)
145                 len = 0;
146         else if (to + len > mtd->size)
147                 len = mtd->size - to;
148         return part->master->write(part->master, to + part->offset,
149                                     len, retlen, buf);
150 }
151
152 static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
153                 size_t *retlen, const u_char *buf)
154 {
155         struct mtd_part *part = PART(mtd);
156         if (!(mtd->flags & MTD_WRITEABLE))
157                 return -EROFS;
158         if (to >= mtd->size)
159                 len = 0;
160         else if (to + len > mtd->size)
161                 len = mtd->size - to;
162         return part->master->panic_write(part->master, to + part->offset,
163                                     len, retlen, buf);
164 }
165
166 static int part_write_oob(struct mtd_info *mtd, loff_t to,
167                 struct mtd_oob_ops *ops)
168 {
169         struct mtd_part *part = PART(mtd);
170
171         if (!(mtd->flags & MTD_WRITEABLE))
172                 return -EROFS;
173
174         if (to >= mtd->size)
175                 return -EINVAL;
176         if (ops->datbuf && to + ops->len > mtd->size)
177                 return -EINVAL;
178         return part->master->write_oob(part->master, to + part->offset, ops);
179 }
180
181 static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
182                 size_t len, size_t *retlen, u_char *buf)
183 {
184         struct mtd_part *part = PART(mtd);
185         return part->master->write_user_prot_reg(part->master, from,
186                                         len, retlen, buf);
187 }
188
189 static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
190                 size_t len)
191 {
192         struct mtd_part *part = PART(mtd);
193         return part->master->lock_user_prot_reg(part->master, from, len);
194 }
195
196 static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,
197                 unsigned long count, loff_t to, size_t *retlen)
198 {
199         struct mtd_part *part = PART(mtd);
200         if (!(mtd->flags & MTD_WRITEABLE))
201                 return -EROFS;
202         return part->master->writev(part->master, vecs, count,
203                                         to + part->offset, retlen);
204 }
205
206 static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
207 {
208         struct mtd_part *part = PART(mtd);
209         int ret;
210         if (!(mtd->flags & MTD_WRITEABLE))
211                 return -EROFS;
212         if (instr->addr >= mtd->size)
213                 return -EINVAL;
214         instr->addr += part->offset;
215         ret = part->master->erase(part->master, instr);
216         if (ret) {
217                 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
218                         instr->fail_addr -= part->offset;
219                 instr->addr -= part->offset;
220         }
221         return ret;
222 }
223
224 void mtd_erase_callback(struct erase_info *instr)
225 {
226         if (instr->mtd->erase == part_erase) {
227                 struct mtd_part *part = PART(instr->mtd);
228
229                 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
230                         instr->fail_addr -= part->offset;
231                 instr->addr -= part->offset;
232         }
233         if (instr->callback)
234                 instr->callback(instr);
235 }
236 EXPORT_SYMBOL_GPL(mtd_erase_callback);
237
238 static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
239 {
240         struct mtd_part *part = PART(mtd);
241         if ((len + ofs) > mtd->size)
242                 return -EINVAL;
243         return part->master->lock(part->master, ofs + part->offset, len);
244 }
245
246 static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
247 {
248         struct mtd_part *part = PART(mtd);
249         if ((len + ofs) > mtd->size)
250                 return -EINVAL;
251         return part->master->unlock(part->master, ofs + part->offset, len);
252 }
253
254 static void part_sync(struct mtd_info *mtd)
255 {
256         struct mtd_part *part = PART(mtd);
257         part->master->sync(part->master);
258 }
259
260 static int part_suspend(struct mtd_info *mtd)
261 {
262         struct mtd_part *part = PART(mtd);
263         return part->master->suspend(part->master);
264 }
265
266 static void part_resume(struct mtd_info *mtd)
267 {
268         struct mtd_part *part = PART(mtd);
269         part->master->resume(part->master);
270 }
271
272 static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
273 {
274         struct mtd_part *part = PART(mtd);
275         if (ofs >= mtd->size)
276                 return -EINVAL;
277         ofs += part->offset;
278         return part->master->block_isbad(part->master, ofs);
279 }
280
281 static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
282 {
283         struct mtd_part *part = PART(mtd);
284         int res;
285
286         if (!(mtd->flags & MTD_WRITEABLE))
287                 return -EROFS;
288         if (ofs >= mtd->size)
289                 return -EINVAL;
290         ofs += part->offset;
291         res = part->master->block_markbad(part->master, ofs);
292         if (!res)
293                 mtd->ecc_stats.badblocks++;
294         return res;
295 }
296
297 /*
298  * This function unregisters and destroy all slave MTD objects which are
299  * attached to the given master MTD object.
300  */
301
302 int del_mtd_partitions(struct mtd_info *master)
303 {
304         struct mtd_part *slave, *next;
305
306         list_for_each_entry_safe(slave, next, &mtd_partitions, list)
307                 if (slave->master == master) {
308                         list_del(&slave->list);
309                         if (slave->registered)
310                                 del_mtd_device(&slave->mtd);
311                         kfree(slave);
312                 }
313
314         return 0;
315 }
316 EXPORT_SYMBOL(del_mtd_partitions);
317
318 static struct mtd_part *add_one_partition(struct mtd_info *master,
319                 const struct mtd_partition *part, int partno,
320                 uint64_t cur_offset)
321 {
322         struct mtd_part *slave;
323
324         /* allocate the partition structure */
325         slave = kzalloc(sizeof(*slave), GFP_KERNEL);
326         if (!slave) {
327                 printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
328                         master->name);
329                 del_mtd_partitions(master);
330                 return NULL;
331         }
332         list_add(&slave->list, &mtd_partitions);
333
334         /* set up the MTD object for this partition */
335         slave->mtd.type = master->type;
336         slave->mtd.flags = master->flags & ~part->mask_flags;
337         slave->mtd.size = part->size;
338         slave->mtd.writesize = master->writesize;
339         slave->mtd.oobsize = master->oobsize;
340         slave->mtd.oobavail = master->oobavail;
341         slave->mtd.subpage_sft = master->subpage_sft;
342
343         slave->mtd.name = part->name;
344         slave->mtd.owner = master->owner;
345
346         slave->mtd.read = part_read;
347         slave->mtd.write = part_write;
348
349         if (master->panic_write)
350                 slave->mtd.panic_write = part_panic_write;
351
352         if (master->point && master->unpoint) {
353                 slave->mtd.point = part_point;
354                 slave->mtd.unpoint = part_unpoint;
355         }
356
357         if (master->read_oob)
358                 slave->mtd.read_oob = part_read_oob;
359         if (master->write_oob)
360                 slave->mtd.write_oob = part_write_oob;
361         if (master->read_user_prot_reg)
362                 slave->mtd.read_user_prot_reg = part_read_user_prot_reg;
363         if (master->read_fact_prot_reg)
364                 slave->mtd.read_fact_prot_reg = part_read_fact_prot_reg;
365         if (master->write_user_prot_reg)
366                 slave->mtd.write_user_prot_reg = part_write_user_prot_reg;
367         if (master->lock_user_prot_reg)
368                 slave->mtd.lock_user_prot_reg = part_lock_user_prot_reg;
369         if (master->get_user_prot_info)
370                 slave->mtd.get_user_prot_info = part_get_user_prot_info;
371         if (master->get_fact_prot_info)
372                 slave->mtd.get_fact_prot_info = part_get_fact_prot_info;
373         if (master->sync)
374                 slave->mtd.sync = part_sync;
375         if (!partno && master->suspend && master->resume) {
376                         slave->mtd.suspend = part_suspend;
377                         slave->mtd.resume = part_resume;
378         }
379         if (master->writev)
380                 slave->mtd.writev = part_writev;
381         if (master->lock)
382                 slave->mtd.lock = part_lock;
383         if (master->unlock)
384                 slave->mtd.unlock = part_unlock;
385         if (master->block_isbad)
386                 slave->mtd.block_isbad = part_block_isbad;
387         if (master->block_markbad)
388                 slave->mtd.block_markbad = part_block_markbad;
389         slave->mtd.erase = part_erase;
390         slave->master = master;
391         slave->offset = part->offset;
392         slave->index = partno;
393
394         if (slave->offset == MTDPART_OFS_APPEND)
395                 slave->offset = cur_offset;
396         if (slave->offset == MTDPART_OFS_NXTBLK) {
397                 slave->offset = cur_offset;
398                 if (mtd_mod_by_eb(cur_offset, master) != 0) {
399                         /* Round up to next erasesize */
400                         slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
401                         printk(KERN_NOTICE "Moving partition %d: "
402                                "0x%012llx -> 0x%012llx\n", partno,
403                                (unsigned long long)cur_offset, (unsigned long long)slave->offset);
404                 }
405         }
406         if (slave->mtd.size == MTDPART_SIZ_FULL)
407                 slave->mtd.size = master->size - slave->offset;
408
409         printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
410                 (unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
411
412         /* let's do some sanity checks */
413         if (slave->offset >= master->size) {
414                 /* let's register it anyway to preserve ordering */
415                 slave->offset = 0;
416                 slave->mtd.size = 0;
417                 printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
418                         part->name);
419                 goto out_register;
420         }
421         if (slave->offset + slave->mtd.size > master->size) {
422                 slave->mtd.size = master->size - slave->offset;
423                 printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
424                         part->name, master->name, (unsigned long long)slave->mtd.size);
425         }
426         if (master->numeraseregions > 1) {
427                 /* Deal with variable erase size stuff */
428                 int i, max = master->numeraseregions;
429                 u64 end = slave->offset + slave->mtd.size;
430                 struct mtd_erase_region_info *regions = master->eraseregions;
431
432                 /* Find the first erase regions which is part of this
433                  * partition. */
434                 for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
435                         ;
436                 /* The loop searched for the region _behind_ the first one */
437                 i--;
438
439                 /* Pick biggest erasesize */
440                 for (; i < max && regions[i].offset < end; i++) {
441                         if (slave->mtd.erasesize < regions[i].erasesize) {
442                                 slave->mtd.erasesize = regions[i].erasesize;
443                         }
444                 }
445                 BUG_ON(slave->mtd.erasesize == 0);
446         } else {
447                 /* Single erase size */
448                 slave->mtd.erasesize = master->erasesize;
449         }
450
451         if ((slave->mtd.flags & MTD_WRITEABLE) &&
452             mtd_mod_by_eb(slave->offset, &slave->mtd)) {
453                 /* Doesn't start on a boundary of major erase size */
454                 /* FIXME: Let it be writable if it is on a boundary of
455                  * _minor_ erase size though */
456                 slave->mtd.flags &= ~MTD_WRITEABLE;
457                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
458                         part->name);
459         }
460         if ((slave->mtd.flags & MTD_WRITEABLE) &&
461             mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) {
462                 slave->mtd.flags &= ~MTD_WRITEABLE;
463                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
464                         part->name);
465         }
466
467         slave->mtd.ecclayout = master->ecclayout;
468         if (master->block_isbad) {
469                 uint64_t offs = 0;
470
471                 while (offs < slave->mtd.size) {
472                         if (master->block_isbad(master,
473                                                 offs + slave->offset))
474                                 slave->mtd.ecc_stats.badblocks++;
475                         offs += slave->mtd.erasesize;
476                 }
477         }
478
479 out_register:
480         if (part->mtdp) {
481                 /* store the object pointer (caller may or may not register it*/
482                 *part->mtdp = &slave->mtd;
483                 slave->registered = 0;
484         } else {
485                 /* register our partition */
486                 add_mtd_device(&slave->mtd);
487                 slave->registered = 1;
488         }
489         return slave;
490 }
491
492 /*
493  * This function, given a master MTD object and a partition table, creates
494  * and registers slave MTD objects which are bound to the master according to
495  * the partition definitions.
496  * (Q: should we register the master MTD object as well?)
497  */
498
499 int add_mtd_partitions(struct mtd_info *master,
500                        const struct mtd_partition *parts,
501                        int nbparts)
502 {
503         struct mtd_part *slave;
504         uint64_t cur_offset = 0;
505         int i;
506
507         printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
508
509         for (i = 0; i < nbparts; i++) {
510                 slave = add_one_partition(master, parts + i, i, cur_offset);
511                 if (!slave)
512                         return -ENOMEM;
513                 cur_offset = slave->offset + slave->mtd.size;
514         }
515
516         return 0;
517 }
518 EXPORT_SYMBOL(add_mtd_partitions);
519
520 static DEFINE_SPINLOCK(part_parser_lock);
521 static LIST_HEAD(part_parsers);
522
523 static struct mtd_part_parser *get_partition_parser(const char *name)
524 {
525         struct mtd_part_parser *p, *ret = NULL;
526
527         spin_lock(&part_parser_lock);
528
529         list_for_each_entry(p, &part_parsers, list)
530                 if (!strcmp(p->name, name) && try_module_get(p->owner)) {
531                         ret = p;
532                         break;
533                 }
534
535         spin_unlock(&part_parser_lock);
536
537         return ret;
538 }
539
540 int register_mtd_parser(struct mtd_part_parser *p)
541 {
542         spin_lock(&part_parser_lock);
543         list_add(&p->list, &part_parsers);
544         spin_unlock(&part_parser_lock);
545
546         return 0;
547 }
548 EXPORT_SYMBOL_GPL(register_mtd_parser);
549
550 int deregister_mtd_parser(struct mtd_part_parser *p)
551 {
552         spin_lock(&part_parser_lock);
553         list_del(&p->list);
554         spin_unlock(&part_parser_lock);
555         return 0;
556 }
557 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
558
559 int parse_mtd_partitions(struct mtd_info *master, const char **types,
560                          struct mtd_partition **pparts, unsigned long origin)
561 {
562         struct mtd_part_parser *parser;
563         int ret = 0;
564
565         for ( ; ret <= 0 && *types; types++) {
566                 parser = get_partition_parser(*types);
567                 if (!parser && !request_module("%s", *types))
568                                 parser = get_partition_parser(*types);
569                 if (!parser) {
570                         printk(KERN_NOTICE "%s partition parsing not available\n",
571                                *types);
572                         continue;
573                 }
574                 ret = (*parser->parse_fn)(master, pparts, origin);
575                 if (ret > 0) {
576                         printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
577                                ret, parser->name, master->name);
578                 }
579                 put_partition_parser(parser);
580         }
581         return ret;
582 }
583 EXPORT_SYMBOL_GPL(parse_mtd_partitions);