2 * Core registration and callback routines for MTD
5 * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>
6 * Copyright © 2006 Red Hat UK Limited
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
24 #include <linux/module.h>
25 #include <linux/kernel.h>
26 #include <linux/ptrace.h>
27 #include <linux/seq_file.h>
28 #include <linux/string.h>
29 #include <linux/timer.h>
30 #include <linux/major.h>
32 #include <linux/err.h>
33 #include <linux/ioctl.h>
34 #include <linux/init.h>
35 #include <linux/proc_fs.h>
36 #include <linux/idr.h>
37 #include <linux/backing-dev.h>
38 #include <linux/gfp.h>
39 #include <linux/slab.h>
40 #include <linux/reboot.h>
42 #include <linux/mtd/mtd.h>
43 #include <linux/mtd/partitions.h>
47 static struct backing_dev_info mtd_bdi
= {
50 static int mtd_cls_suspend(struct device
*dev
, pm_message_t state
);
51 static int mtd_cls_resume(struct device
*dev
);
53 static struct class mtd_class
= {
56 .suspend
= mtd_cls_suspend
,
57 .resume
= mtd_cls_resume
,
60 static DEFINE_IDR(mtd_idr
);
62 /* These are exported solely for the purpose of mtd_blkdevs.c. You
63 should not use them for _anything_ else */
64 DEFINE_MUTEX(mtd_table_mutex
);
65 EXPORT_SYMBOL_GPL(mtd_table_mutex
);
67 struct mtd_info
*__mtd_next_device(int i
)
69 return idr_get_next(&mtd_idr
, &i
);
71 EXPORT_SYMBOL_GPL(__mtd_next_device
);
73 static LIST_HEAD(mtd_notifiers
);
76 #define MTD_DEVT(index) MKDEV(MTD_CHAR_MAJOR, (index)*2)
78 /* REVISIT once MTD uses the driver model better, whoever allocates
79 * the mtd_info will probably want to use the release() hook...
81 static void mtd_release(struct device
*dev
)
83 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
84 dev_t index
= MTD_DEVT(mtd
->index
);
86 /* remove /dev/mtdXro node */
87 device_destroy(&mtd_class
, index
+ 1);
90 static int mtd_cls_suspend(struct device
*dev
, pm_message_t state
)
92 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
94 return mtd
? mtd_suspend(mtd
) : 0;
97 static int mtd_cls_resume(struct device
*dev
)
99 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
106 static ssize_t
mtd_type_show(struct device
*dev
,
107 struct device_attribute
*attr
, char *buf
)
109 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
134 case MTD_MLCNANDFLASH
:
141 return snprintf(buf
, PAGE_SIZE
, "%s\n", type
);
143 static DEVICE_ATTR(type
, S_IRUGO
, mtd_type_show
, NULL
);
145 static ssize_t
mtd_flags_show(struct device
*dev
,
146 struct device_attribute
*attr
, char *buf
)
148 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
150 return snprintf(buf
, PAGE_SIZE
, "0x%lx\n", (unsigned long)mtd
->flags
);
153 static DEVICE_ATTR(flags
, S_IRUGO
, mtd_flags_show
, NULL
);
155 static ssize_t
mtd_size_show(struct device
*dev
,
156 struct device_attribute
*attr
, char *buf
)
158 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
160 return snprintf(buf
, PAGE_SIZE
, "%llu\n",
161 (unsigned long long)mtd
->size
);
164 static DEVICE_ATTR(size
, S_IRUGO
, mtd_size_show
, NULL
);
166 static ssize_t
mtd_erasesize_show(struct device
*dev
,
167 struct device_attribute
*attr
, char *buf
)
169 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
171 return snprintf(buf
, PAGE_SIZE
, "%lu\n", (unsigned long)mtd
->erasesize
);
174 static DEVICE_ATTR(erasesize
, S_IRUGO
, mtd_erasesize_show
, NULL
);
176 static ssize_t
mtd_writesize_show(struct device
*dev
,
177 struct device_attribute
*attr
, char *buf
)
179 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
181 return snprintf(buf
, PAGE_SIZE
, "%lu\n", (unsigned long)mtd
->writesize
);
184 static DEVICE_ATTR(writesize
, S_IRUGO
, mtd_writesize_show
, NULL
);
186 static ssize_t
mtd_subpagesize_show(struct device
*dev
,
187 struct device_attribute
*attr
, char *buf
)
189 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
190 unsigned int subpagesize
= mtd
->writesize
>> mtd
->subpage_sft
;
192 return snprintf(buf
, PAGE_SIZE
, "%u\n", subpagesize
);
195 static DEVICE_ATTR(subpagesize
, S_IRUGO
, mtd_subpagesize_show
, NULL
);
197 static ssize_t
mtd_oobsize_show(struct device
*dev
,
198 struct device_attribute
*attr
, char *buf
)
200 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
202 return snprintf(buf
, PAGE_SIZE
, "%lu\n", (unsigned long)mtd
->oobsize
);
205 static DEVICE_ATTR(oobsize
, S_IRUGO
, mtd_oobsize_show
, NULL
);
207 static ssize_t
mtd_numeraseregions_show(struct device
*dev
,
208 struct device_attribute
*attr
, char *buf
)
210 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
212 return snprintf(buf
, PAGE_SIZE
, "%u\n", mtd
->numeraseregions
);
215 static DEVICE_ATTR(numeraseregions
, S_IRUGO
, mtd_numeraseregions_show
,
218 static ssize_t
mtd_name_show(struct device
*dev
,
219 struct device_attribute
*attr
, char *buf
)
221 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
223 return snprintf(buf
, PAGE_SIZE
, "%s\n", mtd
->name
);
226 static DEVICE_ATTR(name
, S_IRUGO
, mtd_name_show
, NULL
);
228 static ssize_t
mtd_ecc_strength_show(struct device
*dev
,
229 struct device_attribute
*attr
, char *buf
)
231 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
233 return snprintf(buf
, PAGE_SIZE
, "%u\n", mtd
->ecc_strength
);
235 static DEVICE_ATTR(ecc_strength
, S_IRUGO
, mtd_ecc_strength_show
, NULL
);
237 static ssize_t
mtd_bitflip_threshold_show(struct device
*dev
,
238 struct device_attribute
*attr
,
241 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
243 return snprintf(buf
, PAGE_SIZE
, "%u\n", mtd
->bitflip_threshold
);
246 static ssize_t
mtd_bitflip_threshold_store(struct device
*dev
,
247 struct device_attribute
*attr
,
248 const char *buf
, size_t count
)
250 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
251 unsigned int bitflip_threshold
;
254 retval
= kstrtouint(buf
, 0, &bitflip_threshold
);
258 mtd
->bitflip_threshold
= bitflip_threshold
;
261 static DEVICE_ATTR(bitflip_threshold
, S_IRUGO
| S_IWUSR
,
262 mtd_bitflip_threshold_show
,
263 mtd_bitflip_threshold_store
);
265 static ssize_t
mtd_ecc_step_size_show(struct device
*dev
,
266 struct device_attribute
*attr
, char *buf
)
268 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
270 return snprintf(buf
, PAGE_SIZE
, "%u\n", mtd
->ecc_step_size
);
273 static DEVICE_ATTR(ecc_step_size
, S_IRUGO
, mtd_ecc_step_size_show
, NULL
);
275 static ssize_t
mtd_ecc_stats_corrected_show(struct device
*dev
,
276 struct device_attribute
*attr
, char *buf
)
278 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
279 struct mtd_ecc_stats
*ecc_stats
= &mtd
->ecc_stats
;
281 return snprintf(buf
, PAGE_SIZE
, "%u\n", ecc_stats
->corrected
);
283 static DEVICE_ATTR(corrected_bits
, S_IRUGO
,
284 mtd_ecc_stats_corrected_show
, NULL
);
286 static ssize_t
mtd_ecc_stats_errors_show(struct device
*dev
,
287 struct device_attribute
*attr
, char *buf
)
289 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
290 struct mtd_ecc_stats
*ecc_stats
= &mtd
->ecc_stats
;
292 return snprintf(buf
, PAGE_SIZE
, "%u\n", ecc_stats
->failed
);
294 static DEVICE_ATTR(ecc_failures
, S_IRUGO
, mtd_ecc_stats_errors_show
, NULL
);
296 static ssize_t
mtd_badblocks_show(struct device
*dev
,
297 struct device_attribute
*attr
, char *buf
)
299 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
300 struct mtd_ecc_stats
*ecc_stats
= &mtd
->ecc_stats
;
302 return snprintf(buf
, PAGE_SIZE
, "%u\n", ecc_stats
->badblocks
);
304 static DEVICE_ATTR(bad_blocks
, S_IRUGO
, mtd_badblocks_show
, NULL
);
306 static ssize_t
mtd_bbtblocks_show(struct device
*dev
,
307 struct device_attribute
*attr
, char *buf
)
309 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
310 struct mtd_ecc_stats
*ecc_stats
= &mtd
->ecc_stats
;
312 return snprintf(buf
, PAGE_SIZE
, "%u\n", ecc_stats
->bbtblocks
);
314 static DEVICE_ATTR(bbt_blocks
, S_IRUGO
, mtd_bbtblocks_show
, NULL
);
316 static struct attribute
*mtd_attrs
[] = {
318 &dev_attr_flags
.attr
,
320 &dev_attr_erasesize
.attr
,
321 &dev_attr_writesize
.attr
,
322 &dev_attr_subpagesize
.attr
,
323 &dev_attr_oobsize
.attr
,
324 &dev_attr_numeraseregions
.attr
,
326 &dev_attr_ecc_strength
.attr
,
327 &dev_attr_ecc_step_size
.attr
,
328 &dev_attr_corrected_bits
.attr
,
329 &dev_attr_ecc_failures
.attr
,
330 &dev_attr_bad_blocks
.attr
,
331 &dev_attr_bbt_blocks
.attr
,
332 &dev_attr_bitflip_threshold
.attr
,
335 ATTRIBUTE_GROUPS(mtd
);
337 static struct device_type mtd_devtype
= {
339 .groups
= mtd_groups
,
340 .release
= mtd_release
,
344 unsigned mtd_mmap_capabilities(struct mtd_info
*mtd
)
348 return NOMMU_MAP_COPY
| NOMMU_MAP_DIRECT
| NOMMU_MAP_EXEC
|
349 NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
351 return NOMMU_MAP_COPY
| NOMMU_MAP_DIRECT
| NOMMU_MAP_EXEC
|
354 return NOMMU_MAP_COPY
;
357 EXPORT_SYMBOL_GPL(mtd_mmap_capabilities
);
360 static int mtd_reboot_notifier(struct notifier_block
*n
, unsigned long state
,
363 struct mtd_info
*mtd
;
365 mtd
= container_of(n
, struct mtd_info
, reboot_notifier
);
372 * add_mtd_device - register an MTD device
373 * @mtd: pointer to new MTD device info structure
375 * Add a device to the list of MTD devices present in the system, and
376 * notify each currently active MTD 'user' of its arrival. Returns
377 * zero on success or 1 on failure, which currently will only happen
378 * if there is insufficient memory or a sysfs error.
381 int add_mtd_device(struct mtd_info
*mtd
)
383 struct mtd_notifier
*not;
386 mtd
->backing_dev_info
= &mtd_bdi
;
388 BUG_ON(mtd
->writesize
== 0);
389 mutex_lock(&mtd_table_mutex
);
391 i
= idr_alloc(&mtd_idr
, mtd
, 0, 0, GFP_KERNEL
);
398 /* default value if not set by driver */
399 if (mtd
->bitflip_threshold
== 0)
400 mtd
->bitflip_threshold
= mtd
->ecc_strength
;
402 if (is_power_of_2(mtd
->erasesize
))
403 mtd
->erasesize_shift
= ffs(mtd
->erasesize
) - 1;
405 mtd
->erasesize_shift
= 0;
407 if (is_power_of_2(mtd
->writesize
))
408 mtd
->writesize_shift
= ffs(mtd
->writesize
) - 1;
410 mtd
->writesize_shift
= 0;
412 mtd
->erasesize_mask
= (1 << mtd
->erasesize_shift
) - 1;
413 mtd
->writesize_mask
= (1 << mtd
->writesize_shift
) - 1;
415 /* Some chips always power up locked. Unlock them now */
416 if ((mtd
->flags
& MTD_WRITEABLE
) && (mtd
->flags
& MTD_POWERUP_LOCK
)) {
417 error
= mtd_unlock(mtd
, 0, mtd
->size
);
418 if (error
&& error
!= -EOPNOTSUPP
)
420 "%s: unlock failed, writes may not work\n",
424 /* Caller should have set dev.parent to match the
427 mtd
->dev
.type
= &mtd_devtype
;
428 mtd
->dev
.class = &mtd_class
;
429 mtd
->dev
.devt
= MTD_DEVT(i
);
430 dev_set_name(&mtd
->dev
, "mtd%d", i
);
431 dev_set_drvdata(&mtd
->dev
, mtd
);
432 if (device_register(&mtd
->dev
) != 0)
435 device_create(&mtd_class
, mtd
->dev
.parent
, MTD_DEVT(i
) + 1, NULL
,
438 pr_debug("mtd: Giving out device %d to %s\n", i
, mtd
->name
);
439 /* No need to get a refcount on the module containing
440 the notifier, since we hold the mtd_table_mutex */
441 list_for_each_entry(not, &mtd_notifiers
, list
)
444 mutex_unlock(&mtd_table_mutex
);
445 /* We _know_ we aren't being removed, because
446 our caller is still holding us here. So none
447 of this try_ nonsense, and no bitching about it
449 __module_get(THIS_MODULE
);
453 idr_remove(&mtd_idr
, i
);
455 mutex_unlock(&mtd_table_mutex
);
460 * del_mtd_device - unregister an MTD device
461 * @mtd: pointer to MTD device info structure
463 * Remove a device from the list of MTD devices present in the system,
464 * and notify each currently active MTD 'user' of its departure.
465 * Returns zero on success or 1 on failure, which currently will happen
466 * if the requested device does not appear to be present in the list.
469 int del_mtd_device(struct mtd_info
*mtd
)
472 struct mtd_notifier
*not;
474 mutex_lock(&mtd_table_mutex
);
476 if (idr_find(&mtd_idr
, mtd
->index
) != mtd
) {
481 /* No need to get a refcount on the module containing
482 the notifier, since we hold the mtd_table_mutex */
483 list_for_each_entry(not, &mtd_notifiers
, list
)
487 printk(KERN_NOTICE
"Removing MTD device #%d (%s) with use count %d\n",
488 mtd
->index
, mtd
->name
, mtd
->usecount
);
491 device_unregister(&mtd
->dev
);
493 idr_remove(&mtd_idr
, mtd
->index
);
495 module_put(THIS_MODULE
);
500 mutex_unlock(&mtd_table_mutex
);
505 * mtd_device_parse_register - parse partitions and register an MTD device.
507 * @mtd: the MTD device to register
508 * @types: the list of MTD partition probes to try, see
509 * 'parse_mtd_partitions()' for more information
510 * @parser_data: MTD partition parser-specific data
511 * @parts: fallback partition information to register, if parsing fails;
512 * only valid if %nr_parts > %0
513 * @nr_parts: the number of partitions in parts, if zero then the full
514 * MTD device is registered if no partition info is found
516 * This function aggregates MTD partitions parsing (done by
517 * 'parse_mtd_partitions()') and MTD device and partitions registering. It
518 * basically follows the most common pattern found in many MTD drivers:
520 * * It first tries to probe partitions on MTD device @mtd using parsers
521 * specified in @types (if @types is %NULL, then the default list of parsers
522 * is used, see 'parse_mtd_partitions()' for more information). If none are
523 * found this functions tries to fallback to information specified in
525 * * If any partitioning info was found, this function registers the found
527 * * If no partitions were found this function just registers the MTD device
530 * Returns zero in case of success and a negative error code in case of failure.
532 int mtd_device_parse_register(struct mtd_info
*mtd
, const char * const *types
,
533 struct mtd_part_parser_data
*parser_data
,
534 const struct mtd_partition
*parts
,
538 struct mtd_partition
*real_parts
;
540 err
= parse_mtd_partitions(mtd
, types
, &real_parts
, parser_data
);
541 if (err
<= 0 && nr_parts
&& parts
) {
542 real_parts
= kmemdup(parts
, sizeof(*parts
) * nr_parts
,
551 err
= add_mtd_partitions(mtd
, real_parts
, err
);
553 } else if (err
== 0) {
554 err
= add_mtd_device(mtd
);
560 * FIXME: some drivers unfortunately call this function more than once.
561 * So we have to check if we've already assigned the reboot notifier.
563 * Generally, we can make multiple calls work for most cases, but it
564 * does cause problems with parse_mtd_partitions() above (e.g.,
565 * cmdlineparts will register partitions more than once).
567 if (mtd
->_reboot
&& !mtd
->reboot_notifier
.notifier_call
) {
568 mtd
->reboot_notifier
.notifier_call
= mtd_reboot_notifier
;
569 register_reboot_notifier(&mtd
->reboot_notifier
);
574 EXPORT_SYMBOL_GPL(mtd_device_parse_register
);
577 * mtd_device_unregister - unregister an existing MTD device.
579 * @master: the MTD device to unregister. This will unregister both the master
580 * and any partitions if registered.
582 int mtd_device_unregister(struct mtd_info
*master
)
587 unregister_reboot_notifier(&master
->reboot_notifier
);
589 err
= del_mtd_partitions(master
);
593 if (!device_is_registered(&master
->dev
))
596 return del_mtd_device(master
);
598 EXPORT_SYMBOL_GPL(mtd_device_unregister
);
601 * register_mtd_user - register a 'user' of MTD devices.
602 * @new: pointer to notifier info structure
604 * Registers a pair of callbacks function to be called upon addition
605 * or removal of MTD devices. Causes the 'add' callback to be immediately
606 * invoked for each MTD device currently present in the system.
608 void register_mtd_user (struct mtd_notifier
*new)
610 struct mtd_info
*mtd
;
612 mutex_lock(&mtd_table_mutex
);
614 list_add(&new->list
, &mtd_notifiers
);
616 __module_get(THIS_MODULE
);
618 mtd_for_each_device(mtd
)
621 mutex_unlock(&mtd_table_mutex
);
623 EXPORT_SYMBOL_GPL(register_mtd_user
);
626 * unregister_mtd_user - unregister a 'user' of MTD devices.
627 * @old: pointer to notifier info structure
629 * Removes a callback function pair from the list of 'users' to be
630 * notified upon addition or removal of MTD devices. Causes the
631 * 'remove' callback to be immediately invoked for each MTD device
632 * currently present in the system.
634 int unregister_mtd_user (struct mtd_notifier
*old
)
636 struct mtd_info
*mtd
;
638 mutex_lock(&mtd_table_mutex
);
640 module_put(THIS_MODULE
);
642 mtd_for_each_device(mtd
)
645 list_del(&old
->list
);
646 mutex_unlock(&mtd_table_mutex
);
649 EXPORT_SYMBOL_GPL(unregister_mtd_user
);
652 * get_mtd_device - obtain a validated handle for an MTD device
653 * @mtd: last known address of the required MTD device
654 * @num: internal device number of the required MTD device
656 * Given a number and NULL address, return the num'th entry in the device
657 * table, if any. Given an address and num == -1, search the device table
658 * for a device with that address and return if it's still present. Given
659 * both, return the num'th driver only if its address matches. Return
662 struct mtd_info
*get_mtd_device(struct mtd_info
*mtd
, int num
)
664 struct mtd_info
*ret
= NULL
, *other
;
667 mutex_lock(&mtd_table_mutex
);
670 mtd_for_each_device(other
) {
676 } else if (num
>= 0) {
677 ret
= idr_find(&mtd_idr
, num
);
678 if (mtd
&& mtd
!= ret
)
687 err
= __get_mtd_device(ret
);
691 mutex_unlock(&mtd_table_mutex
);
694 EXPORT_SYMBOL_GPL(get_mtd_device
);
697 int __get_mtd_device(struct mtd_info
*mtd
)
701 if (!try_module_get(mtd
->owner
))
704 if (mtd
->_get_device
) {
705 err
= mtd
->_get_device(mtd
);
708 module_put(mtd
->owner
);
715 EXPORT_SYMBOL_GPL(__get_mtd_device
);
718 * get_mtd_device_nm - obtain a validated handle for an MTD device by
720 * @name: MTD device name to open
722 * This function returns MTD device description structure in case of
723 * success and an error code in case of failure.
725 struct mtd_info
*get_mtd_device_nm(const char *name
)
728 struct mtd_info
*mtd
= NULL
, *other
;
730 mutex_lock(&mtd_table_mutex
);
732 mtd_for_each_device(other
) {
733 if (!strcmp(name
, other
->name
)) {
742 err
= __get_mtd_device(mtd
);
746 mutex_unlock(&mtd_table_mutex
);
750 mutex_unlock(&mtd_table_mutex
);
753 EXPORT_SYMBOL_GPL(get_mtd_device_nm
);
755 void put_mtd_device(struct mtd_info
*mtd
)
757 mutex_lock(&mtd_table_mutex
);
758 __put_mtd_device(mtd
);
759 mutex_unlock(&mtd_table_mutex
);
762 EXPORT_SYMBOL_GPL(put_mtd_device
);
764 void __put_mtd_device(struct mtd_info
*mtd
)
767 BUG_ON(mtd
->usecount
< 0);
769 if (mtd
->_put_device
)
770 mtd
->_put_device(mtd
);
772 module_put(mtd
->owner
);
774 EXPORT_SYMBOL_GPL(__put_mtd_device
);
777 * Erase is an asynchronous operation. Device drivers are supposed
778 * to call instr->callback() whenever the operation completes, even
779 * if it completes with a failure.
780 * Callers are supposed to pass a callback function and wait for it
781 * to be called before writing to the block.
783 int mtd_erase(struct mtd_info
*mtd
, struct erase_info
*instr
)
785 if (instr
->addr
>= mtd
->size
|| instr
->len
> mtd
->size
- instr
->addr
)
787 if (!(mtd
->flags
& MTD_WRITEABLE
))
789 instr
->fail_addr
= MTD_FAIL_ADDR_UNKNOWN
;
791 instr
->state
= MTD_ERASE_DONE
;
792 mtd_erase_callback(instr
);
795 return mtd
->_erase(mtd
, instr
);
797 EXPORT_SYMBOL_GPL(mtd_erase
);
800 * This stuff for eXecute-In-Place. phys is optional and may be set to NULL.
802 int mtd_point(struct mtd_info
*mtd
, loff_t from
, size_t len
, size_t *retlen
,
803 void **virt
, resource_size_t
*phys
)
811 if (from
< 0 || from
>= mtd
->size
|| len
> mtd
->size
- from
)
815 return mtd
->_point(mtd
, from
, len
, retlen
, virt
, phys
);
817 EXPORT_SYMBOL_GPL(mtd_point
);
819 /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
820 int mtd_unpoint(struct mtd_info
*mtd
, loff_t from
, size_t len
)
824 if (from
< 0 || from
>= mtd
->size
|| len
> mtd
->size
- from
)
828 return mtd
->_unpoint(mtd
, from
, len
);
830 EXPORT_SYMBOL_GPL(mtd_unpoint
);
833 * Allow NOMMU mmap() to directly map the device (if not NULL)
834 * - return the address to which the offset maps
835 * - return -ENOSYS to indicate refusal to do the mapping
837 unsigned long mtd_get_unmapped_area(struct mtd_info
*mtd
, unsigned long len
,
838 unsigned long offset
, unsigned long flags
)
840 if (!mtd
->_get_unmapped_area
)
842 if (offset
>= mtd
->size
|| len
> mtd
->size
- offset
)
844 return mtd
->_get_unmapped_area(mtd
, len
, offset
, flags
);
846 EXPORT_SYMBOL_GPL(mtd_get_unmapped_area
);
848 int mtd_read(struct mtd_info
*mtd
, loff_t from
, size_t len
, size_t *retlen
,
853 if (from
< 0 || from
>= mtd
->size
|| len
> mtd
->size
- from
)
859 * In the absence of an error, drivers return a non-negative integer
860 * representing the maximum number of bitflips that were corrected on
861 * any one ecc region (if applicable; zero otherwise).
863 ret_code
= mtd
->_read(mtd
, from
, len
, retlen
, buf
);
864 if (unlikely(ret_code
< 0))
866 if (mtd
->ecc_strength
== 0)
867 return 0; /* device lacks ecc */
868 return ret_code
>= mtd
->bitflip_threshold
? -EUCLEAN
: 0;
870 EXPORT_SYMBOL_GPL(mtd_read
);
872 int mtd_write(struct mtd_info
*mtd
, loff_t to
, size_t len
, size_t *retlen
,
876 if (to
< 0 || to
>= mtd
->size
|| len
> mtd
->size
- to
)
878 if (!mtd
->_write
|| !(mtd
->flags
& MTD_WRITEABLE
))
882 return mtd
->_write(mtd
, to
, len
, retlen
, buf
);
884 EXPORT_SYMBOL_GPL(mtd_write
);
887 * In blackbox flight recorder like scenarios we want to make successful writes
888 * in interrupt context. panic_write() is only intended to be called when its
889 * known the kernel is about to panic and we need the write to succeed. Since
890 * the kernel is not going to be running for much longer, this function can
891 * break locks and delay to ensure the write succeeds (but not sleep).
893 int mtd_panic_write(struct mtd_info
*mtd
, loff_t to
, size_t len
, size_t *retlen
,
897 if (!mtd
->_panic_write
)
899 if (to
< 0 || to
>= mtd
->size
|| len
> mtd
->size
- to
)
901 if (!(mtd
->flags
& MTD_WRITEABLE
))
905 return mtd
->_panic_write(mtd
, to
, len
, retlen
, buf
);
907 EXPORT_SYMBOL_GPL(mtd_panic_write
);
909 int mtd_read_oob(struct mtd_info
*mtd
, loff_t from
, struct mtd_oob_ops
*ops
)
912 ops
->retlen
= ops
->oobretlen
= 0;
916 * In cases where ops->datbuf != NULL, mtd->_read_oob() has semantics
917 * similar to mtd->_read(), returning a non-negative integer
918 * representing max bitflips. In other cases, mtd->_read_oob() may
919 * return -EUCLEAN. In all cases, perform similar logic to mtd_read().
921 ret_code
= mtd
->_read_oob(mtd
, from
, ops
);
922 if (unlikely(ret_code
< 0))
924 if (mtd
->ecc_strength
== 0)
925 return 0; /* device lacks ecc */
926 return ret_code
>= mtd
->bitflip_threshold
? -EUCLEAN
: 0;
928 EXPORT_SYMBOL_GPL(mtd_read_oob
);
931 * Method to access the protection register area, present in some flash
932 * devices. The user data is one time programmable but the factory data is read
935 int mtd_get_fact_prot_info(struct mtd_info
*mtd
, size_t len
, size_t *retlen
,
936 struct otp_info
*buf
)
938 if (!mtd
->_get_fact_prot_info
)
942 return mtd
->_get_fact_prot_info(mtd
, len
, retlen
, buf
);
944 EXPORT_SYMBOL_GPL(mtd_get_fact_prot_info
);
946 int mtd_read_fact_prot_reg(struct mtd_info
*mtd
, loff_t from
, size_t len
,
947 size_t *retlen
, u_char
*buf
)
950 if (!mtd
->_read_fact_prot_reg
)
954 return mtd
->_read_fact_prot_reg(mtd
, from
, len
, retlen
, buf
);
956 EXPORT_SYMBOL_GPL(mtd_read_fact_prot_reg
);
958 int mtd_get_user_prot_info(struct mtd_info
*mtd
, size_t len
, size_t *retlen
,
959 struct otp_info
*buf
)
961 if (!mtd
->_get_user_prot_info
)
965 return mtd
->_get_user_prot_info(mtd
, len
, retlen
, buf
);
967 EXPORT_SYMBOL_GPL(mtd_get_user_prot_info
);
969 int mtd_read_user_prot_reg(struct mtd_info
*mtd
, loff_t from
, size_t len
,
970 size_t *retlen
, u_char
*buf
)
973 if (!mtd
->_read_user_prot_reg
)
977 return mtd
->_read_user_prot_reg(mtd
, from
, len
, retlen
, buf
);
979 EXPORT_SYMBOL_GPL(mtd_read_user_prot_reg
);
981 int mtd_write_user_prot_reg(struct mtd_info
*mtd
, loff_t to
, size_t len
,
982 size_t *retlen
, u_char
*buf
)
987 if (!mtd
->_write_user_prot_reg
)
991 ret
= mtd
->_write_user_prot_reg(mtd
, to
, len
, retlen
, buf
);
996 * If no data could be written at all, we are out of memory and
997 * must return -ENOSPC.
999 return (*retlen
) ? 0 : -ENOSPC
;
1001 EXPORT_SYMBOL_GPL(mtd_write_user_prot_reg
);
1003 int mtd_lock_user_prot_reg(struct mtd_info
*mtd
, loff_t from
, size_t len
)
1005 if (!mtd
->_lock_user_prot_reg
)
1009 return mtd
->_lock_user_prot_reg(mtd
, from
, len
);
1011 EXPORT_SYMBOL_GPL(mtd_lock_user_prot_reg
);
1013 /* Chip-supported device locking */
1014 int mtd_lock(struct mtd_info
*mtd
, loff_t ofs
, uint64_t len
)
1018 if (ofs
< 0 || ofs
>= mtd
->size
|| len
> mtd
->size
- ofs
)
1022 return mtd
->_lock(mtd
, ofs
, len
);
1024 EXPORT_SYMBOL_GPL(mtd_lock
);
1026 int mtd_unlock(struct mtd_info
*mtd
, loff_t ofs
, uint64_t len
)
1030 if (ofs
< 0 || ofs
>= mtd
->size
|| len
> mtd
->size
- ofs
)
1034 return mtd
->_unlock(mtd
, ofs
, len
);
1036 EXPORT_SYMBOL_GPL(mtd_unlock
);
1038 int mtd_is_locked(struct mtd_info
*mtd
, loff_t ofs
, uint64_t len
)
1040 if (!mtd
->_is_locked
)
1042 if (ofs
< 0 || ofs
>= mtd
->size
|| len
> mtd
->size
- ofs
)
1046 return mtd
->_is_locked(mtd
, ofs
, len
);
1048 EXPORT_SYMBOL_GPL(mtd_is_locked
);
1050 int mtd_block_isreserved(struct mtd_info
*mtd
, loff_t ofs
)
1052 if (ofs
< 0 || ofs
>= mtd
->size
)
1054 if (!mtd
->_block_isreserved
)
1056 return mtd
->_block_isreserved(mtd
, ofs
);
1058 EXPORT_SYMBOL_GPL(mtd_block_isreserved
);
1060 int mtd_block_isbad(struct mtd_info
*mtd
, loff_t ofs
)
1062 if (ofs
< 0 || ofs
>= mtd
->size
)
1064 if (!mtd
->_block_isbad
)
1066 return mtd
->_block_isbad(mtd
, ofs
);
1068 EXPORT_SYMBOL_GPL(mtd_block_isbad
);
1070 int mtd_block_markbad(struct mtd_info
*mtd
, loff_t ofs
)
1072 if (!mtd
->_block_markbad
)
1074 if (ofs
< 0 || ofs
>= mtd
->size
)
1076 if (!(mtd
->flags
& MTD_WRITEABLE
))
1078 return mtd
->_block_markbad(mtd
, ofs
);
1080 EXPORT_SYMBOL_GPL(mtd_block_markbad
);
1083 * default_mtd_writev - the default writev method
1084 * @mtd: mtd device description object pointer
1085 * @vecs: the vectors to write
1086 * @count: count of vectors in @vecs
1087 * @to: the MTD device offset to write to
1088 * @retlen: on exit contains the count of bytes written to the MTD device.
1090 * This function returns zero in case of success and a negative error code in
1093 static int default_mtd_writev(struct mtd_info
*mtd
, const struct kvec
*vecs
,
1094 unsigned long count
, loff_t to
, size_t *retlen
)
1097 size_t totlen
= 0, thislen
;
1100 for (i
= 0; i
< count
; i
++) {
1101 if (!vecs
[i
].iov_len
)
1103 ret
= mtd_write(mtd
, to
, vecs
[i
].iov_len
, &thislen
,
1106 if (ret
|| thislen
!= vecs
[i
].iov_len
)
1108 to
+= vecs
[i
].iov_len
;
1115 * mtd_writev - the vector-based MTD write method
1116 * @mtd: mtd device description object pointer
1117 * @vecs: the vectors to write
1118 * @count: count of vectors in @vecs
1119 * @to: the MTD device offset to write to
1120 * @retlen: on exit contains the count of bytes written to the MTD device.
1122 * This function returns zero in case of success and a negative error code in
1125 int mtd_writev(struct mtd_info
*mtd
, const struct kvec
*vecs
,
1126 unsigned long count
, loff_t to
, size_t *retlen
)
1129 if (!(mtd
->flags
& MTD_WRITEABLE
))
1132 return default_mtd_writev(mtd
, vecs
, count
, to
, retlen
);
1133 return mtd
->_writev(mtd
, vecs
, count
, to
, retlen
);
1135 EXPORT_SYMBOL_GPL(mtd_writev
);
1138 * mtd_kmalloc_up_to - allocate a contiguous buffer up to the specified size
1139 * @mtd: mtd device description object pointer
1140 * @size: a pointer to the ideal or maximum size of the allocation, points
1141 * to the actual allocation size on success.
1143 * This routine attempts to allocate a contiguous kernel buffer up to
1144 * the specified size, backing off the size of the request exponentially
1145 * until the request succeeds or until the allocation size falls below
1146 * the system page size. This attempts to make sure it does not adversely
1147 * impact system performance, so when allocating more than one page, we
1148 * ask the memory allocator to avoid re-trying, swapping, writing back
1149 * or performing I/O.
1151 * Note, this function also makes sure that the allocated buffer is aligned to
1152 * the MTD device's min. I/O unit, i.e. the "mtd->writesize" value.
1154 * This is called, for example by mtd_{read,write} and jffs2_scan_medium,
1155 * to handle smaller (i.e. degraded) buffer allocations under low- or
1156 * fragmented-memory situations where such reduced allocations, from a
1157 * requested ideal, are allowed.
1159 * Returns a pointer to the allocated buffer on success; otherwise, NULL.
1161 void *mtd_kmalloc_up_to(const struct mtd_info
*mtd
, size_t *size
)
1163 gfp_t flags
= __GFP_NOWARN
| __GFP_WAIT
|
1164 __GFP_NORETRY
| __GFP_NO_KSWAPD
;
1165 size_t min_alloc
= max_t(size_t, mtd
->writesize
, PAGE_SIZE
);
1168 *size
= min_t(size_t, *size
, KMALLOC_MAX_SIZE
);
1170 while (*size
> min_alloc
) {
1171 kbuf
= kmalloc(*size
, flags
);
1176 *size
= ALIGN(*size
, mtd
->writesize
);
1180 * For the last resort allocation allow 'kmalloc()' to do all sorts of
1181 * things (write-back, dropping caches, etc) by using GFP_KERNEL.
1183 return kmalloc(*size
, GFP_KERNEL
);
1185 EXPORT_SYMBOL_GPL(mtd_kmalloc_up_to
);
1187 #ifdef CONFIG_PROC_FS
1189 /*====================================================================*/
1190 /* Support for /proc/mtd */
1192 static int mtd_proc_show(struct seq_file
*m
, void *v
)
1194 struct mtd_info
*mtd
;
1196 seq_puts(m
, "dev: size erasesize name\n");
1197 mutex_lock(&mtd_table_mutex
);
1198 mtd_for_each_device(mtd
) {
1199 seq_printf(m
, "mtd%d: %8.8llx %8.8x \"%s\"\n",
1200 mtd
->index
, (unsigned long long)mtd
->size
,
1201 mtd
->erasesize
, mtd
->name
);
1203 mutex_unlock(&mtd_table_mutex
);
1207 static int mtd_proc_open(struct inode
*inode
, struct file
*file
)
1209 return single_open(file
, mtd_proc_show
, NULL
);
1212 static const struct file_operations mtd_proc_ops
= {
1213 .open
= mtd_proc_open
,
1215 .llseek
= seq_lseek
,
1216 .release
= single_release
,
1218 #endif /* CONFIG_PROC_FS */
1220 /*====================================================================*/
1223 static int __init
mtd_bdi_init(struct backing_dev_info
*bdi
, const char *name
)
1227 ret
= bdi_init(bdi
);
1229 ret
= bdi_register(bdi
, NULL
, "%s", name
);
1237 static struct proc_dir_entry
*proc_mtd
;
1239 static int __init
init_mtd(void)
1243 ret
= class_register(&mtd_class
);
1247 ret
= mtd_bdi_init(&mtd_bdi
, "mtd");
1251 proc_mtd
= proc_create("mtd", 0, NULL
, &mtd_proc_ops
);
1253 ret
= init_mtdchar();
1261 remove_proc_entry("mtd", NULL
);
1263 class_unregister(&mtd_class
);
1265 pr_err("Error registering mtd class or bdi: %d\n", ret
);
1269 static void __exit
cleanup_mtd(void)
1273 remove_proc_entry("mtd", NULL
);
1274 class_unregister(&mtd_class
);
1275 bdi_destroy(&mtd_bdi
);
1278 module_init(init_mtd
);
1279 module_exit(cleanup_mtd
);
1281 MODULE_LICENSE("GPL");
1282 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
1283 MODULE_DESCRIPTION("Core MTD registration and access routines");