rtc-ds1307: typo fix found by coverity
[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  * $Id: mtdpart.c,v 1.55 2005/11/07 11:14:20 gleixner Exp $
9  *
10  *      02-21-2002      Thomas Gleixner <gleixner@autronix.de>
11  *                      added support for read_oob, write_oob
12  */
13
14 #include <linux/module.h>
15 #include <linux/types.h>
16 #include <linux/kernel.h>
17 #include <linux/slab.h>
18 #include <linux/list.h>
19 #include <linux/kmod.h>
20 #include <linux/mtd/mtd.h>
21 #include <linux/mtd/partitions.h>
22 #include <linux/mtd/compatmac.h>
23
24 /* Our partition linked list */
25 static LIST_HEAD(mtd_partitions);
26
27 /* Our partition node structure */
28 struct mtd_part {
29         struct mtd_info mtd;
30         struct mtd_info *master;
31         u_int32_t offset;
32         int index;
33         struct list_head list;
34         int registered;
35 };
36
37 /*
38  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
39  * the pointer to that structure with this macro.
40  */
41 #define PART(x)  ((struct mtd_part *)(x))
42
43
44 /*
45  * MTD methods which simply translate the effective address and pass through
46  * to the _real_ device.
47  */
48
49 static int part_read (struct mtd_info *mtd, loff_t from, size_t len,
50                         size_t *retlen, u_char *buf)
51 {
52         struct mtd_part *part = PART(mtd);
53         int res;
54
55         if (from >= mtd->size)
56                 len = 0;
57         else if (from + len > mtd->size)
58                 len = mtd->size - from;
59         res = part->master->read (part->master, from + part->offset,
60                                    len, retlen, buf);
61         if (unlikely(res)) {
62                 if (res == -EUCLEAN)
63                         mtd->ecc_stats.corrected++;
64                 if (res == -EBADMSG)
65                         mtd->ecc_stats.failed++;
66         }
67         return res;
68 }
69
70 static int part_point (struct mtd_info *mtd, loff_t from, size_t len,
71                         size_t *retlen, u_char **buf)
72 {
73         struct mtd_part *part = PART(mtd);
74         if (from >= mtd->size)
75                 len = 0;
76         else if (from + len > mtd->size)
77                 len = mtd->size - from;
78         return part->master->point (part->master, from + part->offset,
79                                     len, retlen, buf);
80 }
81
82 static void part_unpoint (struct mtd_info *mtd, u_char *addr, loff_t from, size_t len)
83 {
84         struct mtd_part *part = PART(mtd);
85
86         part->master->unpoint (part->master, addr, from + part->offset, len);
87 }
88
89 static int part_read_oob(struct mtd_info *mtd, loff_t from,
90                          struct mtd_oob_ops *ops)
91 {
92         struct mtd_part *part = PART(mtd);
93         int res;
94
95         if (from >= mtd->size)
96                 return -EINVAL;
97         if (ops->datbuf && from + ops->len > mtd->size)
98                 return -EINVAL;
99         res = part->master->read_oob(part->master, from + part->offset, ops);
100
101         if (unlikely(res)) {
102                 if (res == -EUCLEAN)
103                         mtd->ecc_stats.corrected++;
104                 if (res == -EBADMSG)
105                         mtd->ecc_stats.failed++;
106         }
107         return res;
108 }
109
110 static int part_read_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
111                         size_t *retlen, u_char *buf)
112 {
113         struct mtd_part *part = PART(mtd);
114         return part->master->read_user_prot_reg (part->master, from,
115                                         len, retlen, buf);
116 }
117
118 static int part_get_user_prot_info (struct mtd_info *mtd,
119                                     struct otp_info *buf, size_t len)
120 {
121         struct mtd_part *part = PART(mtd);
122         return part->master->get_user_prot_info (part->master, buf, len);
123 }
124
125 static int part_read_fact_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
126                         size_t *retlen, u_char *buf)
127 {
128         struct mtd_part *part = PART(mtd);
129         return part->master->read_fact_prot_reg (part->master, from,
130                                         len, retlen, buf);
131 }
132
133 static int part_get_fact_prot_info (struct mtd_info *mtd,
134                                     struct otp_info *buf, size_t len)
135 {
136         struct mtd_part *part = PART(mtd);
137         return part->master->get_fact_prot_info (part->master, buf, len);
138 }
139
140 static int part_write (struct mtd_info *mtd, loff_t to, size_t len,
141                         size_t *retlen, const u_char *buf)
142 {
143         struct mtd_part *part = PART(mtd);
144         if (!(mtd->flags & MTD_WRITEABLE))
145                 return -EROFS;
146         if (to >= mtd->size)
147                 len = 0;
148         else if (to + len > mtd->size)
149                 len = mtd->size - to;
150         return part->master->write (part->master, to + part->offset,
151                                     len, retlen, buf);
152 }
153
154 static int part_write_oob(struct mtd_info *mtd, loff_t to,
155                          struct mtd_oob_ops *ops)
156 {
157         struct mtd_part *part = PART(mtd);
158
159         if (!(mtd->flags & MTD_WRITEABLE))
160                 return -EROFS;
161
162         if (to >= mtd->size)
163                 return -EINVAL;
164         if (ops->datbuf && to + ops->len > mtd->size)
165                 return -EINVAL;
166         return part->master->write_oob(part->master, to + part->offset, ops);
167 }
168
169 static int part_write_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
170                         size_t *retlen, u_char *buf)
171 {
172         struct mtd_part *part = PART(mtd);
173         return part->master->write_user_prot_reg (part->master, from,
174                                         len, retlen, buf);
175 }
176
177 static int part_lock_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len)
178 {
179         struct mtd_part *part = PART(mtd);
180         return part->master->lock_user_prot_reg (part->master, from, len);
181 }
182
183 static int part_writev (struct mtd_info *mtd,  const struct kvec *vecs,
184                          unsigned long count, loff_t to, size_t *retlen)
185 {
186         struct mtd_part *part = PART(mtd);
187         if (!(mtd->flags & MTD_WRITEABLE))
188                 return -EROFS;
189         return part->master->writev (part->master, vecs, count,
190                                         to + part->offset, retlen);
191 }
192
193 static int part_erase (struct mtd_info *mtd, struct erase_info *instr)
194 {
195         struct mtd_part *part = PART(mtd);
196         int ret;
197         if (!(mtd->flags & MTD_WRITEABLE))
198                 return -EROFS;
199         if (instr->addr >= mtd->size)
200                 return -EINVAL;
201         instr->addr += part->offset;
202         ret = part->master->erase(part->master, instr);
203         if (ret) {
204                 if (instr->fail_addr != 0xffffffff)
205                         instr->fail_addr -= part->offset;
206                 instr->addr -= part->offset;
207         }
208         return ret;
209 }
210
211 void mtd_erase_callback(struct erase_info *instr)
212 {
213         if (instr->mtd->erase == part_erase) {
214                 struct mtd_part *part = PART(instr->mtd);
215
216                 if (instr->fail_addr != 0xffffffff)
217                         instr->fail_addr -= part->offset;
218                 instr->addr -= part->offset;
219         }
220         if (instr->callback)
221                 instr->callback(instr);
222 }
223 EXPORT_SYMBOL_GPL(mtd_erase_callback);
224
225 static int part_lock (struct mtd_info *mtd, loff_t ofs, size_t len)
226 {
227         struct mtd_part *part = PART(mtd);
228         if ((len + ofs) > mtd->size)
229                 return -EINVAL;
230         return part->master->lock(part->master, ofs + part->offset, len);
231 }
232
233 static int part_unlock (struct mtd_info *mtd, loff_t ofs, size_t len)
234 {
235         struct mtd_part *part = PART(mtd);
236         if ((len + ofs) > mtd->size)
237                 return -EINVAL;
238         return part->master->unlock(part->master, ofs + part->offset, len);
239 }
240
241 static void part_sync(struct mtd_info *mtd)
242 {
243         struct mtd_part *part = PART(mtd);
244         part->master->sync(part->master);
245 }
246
247 static int part_suspend(struct mtd_info *mtd)
248 {
249         struct mtd_part *part = PART(mtd);
250         return part->master->suspend(part->master);
251 }
252
253 static void part_resume(struct mtd_info *mtd)
254 {
255         struct mtd_part *part = PART(mtd);
256         part->master->resume(part->master);
257 }
258
259 static int part_block_isbad (struct mtd_info *mtd, loff_t ofs)
260 {
261         struct mtd_part *part = PART(mtd);
262         if (ofs >= mtd->size)
263                 return -EINVAL;
264         ofs += part->offset;
265         return part->master->block_isbad(part->master, ofs);
266 }
267
268 static int part_block_markbad (struct mtd_info *mtd, loff_t ofs)
269 {
270         struct mtd_part *part = PART(mtd);
271         int res;
272
273         if (!(mtd->flags & MTD_WRITEABLE))
274                 return -EROFS;
275         if (ofs >= mtd->size)
276                 return -EINVAL;
277         ofs += part->offset;
278         res = part->master->block_markbad(part->master, ofs);
279         if (!res)
280                 mtd->ecc_stats.badblocks++;
281         return res;
282 }
283
284 /*
285  * This function unregisters and destroy all slave MTD objects which are
286  * attached to the given master MTD object.
287  */
288
289 int del_mtd_partitions(struct mtd_info *master)
290 {
291         struct list_head *node;
292         struct mtd_part *slave;
293
294         for (node = mtd_partitions.next;
295              node != &mtd_partitions;
296              node = node->next) {
297                 slave = list_entry(node, struct mtd_part, list);
298                 if (slave->master == master) {
299                         struct list_head *prev = node->prev;
300                         __list_del(prev, node->next);
301                         if(slave->registered)
302                                 del_mtd_device(&slave->mtd);
303                         kfree(slave);
304                         node = prev;
305                 }
306         }
307
308         return 0;
309 }
310
311 /*
312  * This function, given a master MTD object and a partition table, creates
313  * and registers slave MTD objects which are bound to the master according to
314  * the partition definitions.
315  * (Q: should we register the master MTD object as well?)
316  */
317
318 int add_mtd_partitions(struct mtd_info *master,
319                        const struct mtd_partition *parts,
320                        int nbparts)
321 {
322         struct mtd_part *slave;
323         u_int32_t cur_offset = 0;
324         int i;
325
326         printk (KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
327
328         for (i = 0; i < nbparts; i++) {
329
330                 /* allocate the partition structure */
331                 slave = kzalloc (sizeof(*slave), GFP_KERNEL);
332                 if (!slave) {
333                         printk ("memory allocation error while creating partitions for \"%s\"\n",
334                                 master->name);
335                         del_mtd_partitions(master);
336                         return -ENOMEM;
337                 }
338                 list_add(&slave->list, &mtd_partitions);
339
340                 /* set up the MTD object for this partition */
341                 slave->mtd.type = master->type;
342                 slave->mtd.flags = master->flags & ~parts[i].mask_flags;
343                 slave->mtd.size = parts[i].size;
344                 slave->mtd.writesize = master->writesize;
345                 slave->mtd.oobsize = master->oobsize;
346                 slave->mtd.oobavail = master->oobavail;
347                 slave->mtd.subpage_sft = master->subpage_sft;
348
349                 slave->mtd.name = parts[i].name;
350                 slave->mtd.owner = master->owner;
351
352                 slave->mtd.read = part_read;
353                 slave->mtd.write = part_write;
354
355                 if(master->point && master->unpoint){
356                         slave->mtd.point = part_point;
357                         slave->mtd.unpoint = part_unpoint;
358                 }
359
360                 if (master->read_oob)
361                         slave->mtd.read_oob = part_read_oob;
362                 if (master->write_oob)
363                         slave->mtd.write_oob = part_write_oob;
364                 if(master->read_user_prot_reg)
365                         slave->mtd.read_user_prot_reg = part_read_user_prot_reg;
366                 if(master->read_fact_prot_reg)
367                         slave->mtd.read_fact_prot_reg = part_read_fact_prot_reg;
368                 if(master->write_user_prot_reg)
369                         slave->mtd.write_user_prot_reg = part_write_user_prot_reg;
370                 if(master->lock_user_prot_reg)
371                         slave->mtd.lock_user_prot_reg = part_lock_user_prot_reg;
372                 if(master->get_user_prot_info)
373                         slave->mtd.get_user_prot_info = part_get_user_prot_info;
374                 if(master->get_fact_prot_info)
375                         slave->mtd.get_fact_prot_info = part_get_fact_prot_info;
376                 if (master->sync)
377                         slave->mtd.sync = part_sync;
378                 if (!i && master->suspend && master->resume) {
379                                 slave->mtd.suspend = part_suspend;
380                                 slave->mtd.resume = part_resume;
381                 }
382                 if (master->writev)
383                         slave->mtd.writev = part_writev;
384                 if (master->lock)
385                         slave->mtd.lock = part_lock;
386                 if (master->unlock)
387                         slave->mtd.unlock = part_unlock;
388                 if (master->block_isbad)
389                         slave->mtd.block_isbad = part_block_isbad;
390                 if (master->block_markbad)
391                         slave->mtd.block_markbad = part_block_markbad;
392                 slave->mtd.erase = part_erase;
393                 slave->master = master;
394                 slave->offset = parts[i].offset;
395                 slave->index = i;
396
397                 if (slave->offset == MTDPART_OFS_APPEND)
398                         slave->offset = cur_offset;
399                 if (slave->offset == MTDPART_OFS_NXTBLK) {
400                         slave->offset = cur_offset;
401                         if ((cur_offset % master->erasesize) != 0) {
402                                 /* Round up to next erasesize */
403                                 slave->offset = ((cur_offset / master->erasesize) + 1) * master->erasesize;
404                                 printk(KERN_NOTICE "Moving partition %d: "
405                                        "0x%08x -> 0x%08x\n", i,
406                                        cur_offset, slave->offset);
407                         }
408                 }
409                 if (slave->mtd.size == MTDPART_SIZ_FULL)
410                         slave->mtd.size = master->size - slave->offset;
411                 cur_offset = slave->offset + slave->mtd.size;
412
413                 printk (KERN_NOTICE "0x%08x-0x%08x : \"%s\"\n", slave->offset,
414                         slave->offset + slave->mtd.size, slave->mtd.name);
415
416                 /* let's do some sanity checks */
417                 if (slave->offset >= master->size) {
418                                 /* let's register it anyway to preserve ordering */
419                         slave->offset = 0;
420                         slave->mtd.size = 0;
421                         printk ("mtd: partition \"%s\" is out of reach -- disabled\n",
422                                 parts[i].name);
423                 }
424                 if (slave->offset + slave->mtd.size > master->size) {
425                         slave->mtd.size = master->size - slave->offset;
426                         printk ("mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#x\n",
427                                 parts[i].name, master->name, slave->mtd.size);
428                 }
429                 if (master->numeraseregions>1) {
430                         /* Deal with variable erase size stuff */
431                         int i;
432                         struct mtd_erase_region_info *regions = master->eraseregions;
433
434                         /* Find the first erase regions which is part of this partition. */
435                         for (i=0; i < master->numeraseregions && slave->offset >= regions[i].offset; i++)
436                                 ;
437
438                         for (i--; i < master->numeraseregions && slave->offset + slave->mtd.size > regions[i].offset; i++) {
439                                 if (slave->mtd.erasesize < regions[i].erasesize) {
440                                         slave->mtd.erasesize = regions[i].erasesize;
441                                 }
442                         }
443                 } else {
444                         /* Single erase size */
445                         slave->mtd.erasesize = master->erasesize;
446                 }
447
448                 if ((slave->mtd.flags & MTD_WRITEABLE) &&
449                     (slave->offset % slave->mtd.erasesize)) {
450                         /* Doesn't start on a boundary of major erase size */
451                         /* FIXME: Let it be writable if it is on a boundary of _minor_ erase size though */
452                         slave->mtd.flags &= ~MTD_WRITEABLE;
453                         printk ("mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
454                                 parts[i].name);
455                 }
456                 if ((slave->mtd.flags & MTD_WRITEABLE) &&
457                     (slave->mtd.size % slave->mtd.erasesize)) {
458                         slave->mtd.flags &= ~MTD_WRITEABLE;
459                         printk ("mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
460                                 parts[i].name);
461                 }
462
463                 slave->mtd.ecclayout = master->ecclayout;
464                 if (master->block_isbad) {
465                         uint32_t offs = 0;
466
467                         while(offs < slave->mtd.size) {
468                                 if (master->block_isbad(master,
469                                                         offs + slave->offset))
470                                         slave->mtd.ecc_stats.badblocks++;
471                                 offs += slave->mtd.erasesize;
472                         }
473                 }
474
475                 if(parts[i].mtdp)
476                 {       /* store the object pointer (caller may or may not register it */
477                         *parts[i].mtdp = &slave->mtd;
478                         slave->registered = 0;
479                 }
480                 else
481                 {
482                         /* register our partition */
483                         add_mtd_device(&slave->mtd);
484                         slave->registered = 1;
485                 }
486         }
487
488         return 0;
489 }
490
491 EXPORT_SYMBOL(add_mtd_partitions);
492 EXPORT_SYMBOL(del_mtd_partitions);
493
494 static DEFINE_SPINLOCK(part_parser_lock);
495 static LIST_HEAD(part_parsers);
496
497 static struct mtd_part_parser *get_partition_parser(const char *name)
498 {
499         struct list_head *this;
500         void *ret = NULL;
501         spin_lock(&part_parser_lock);
502
503         list_for_each(this, &part_parsers) {
504                 struct mtd_part_parser *p = list_entry(this, struct mtd_part_parser, list);
505
506                 if (!strcmp(p->name, name) && try_module_get(p->owner)) {
507                         ret = p;
508                         break;
509                 }
510         }
511         spin_unlock(&part_parser_lock);
512
513         return ret;
514 }
515
516 int register_mtd_parser(struct mtd_part_parser *p)
517 {
518         spin_lock(&part_parser_lock);
519         list_add(&p->list, &part_parsers);
520         spin_unlock(&part_parser_lock);
521
522         return 0;
523 }
524
525 int deregister_mtd_parser(struct mtd_part_parser *p)
526 {
527         spin_lock(&part_parser_lock);
528         list_del(&p->list);
529         spin_unlock(&part_parser_lock);
530         return 0;
531 }
532
533 int parse_mtd_partitions(struct mtd_info *master, const char **types,
534                          struct mtd_partition **pparts, unsigned long origin)
535 {
536         struct mtd_part_parser *parser;
537         int ret = 0;
538
539         for ( ; ret <= 0 && *types; types++) {
540                 parser = get_partition_parser(*types);
541 #ifdef CONFIG_KMOD
542                 if (!parser && !request_module("%s", *types))
543                                 parser = get_partition_parser(*types);
544 #endif
545                 if (!parser) {
546                         printk(KERN_NOTICE "%s partition parsing not available\n",
547                                *types);
548                         continue;
549                 }
550                 ret = (*parser->parse_fn)(master, pparts, origin);
551                 if (ret > 0) {
552                         printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
553                                ret, parser->name, master->name);
554                 }
555                 put_partition_parser(parser);
556         }
557         return ret;
558 }
559
560 EXPORT_SYMBOL_GPL(parse_mtd_partitions);
561 EXPORT_SYMBOL_GPL(register_mtd_parser);
562 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
563
564 MODULE_LICENSE("GPL");
565 MODULE_AUTHOR("Nicolas Pitre <nico@cam.org>");
566 MODULE_DESCRIPTION("Generic support for partitioning of MTD devices");