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>
36 #include <linux/proc_fs.h>
37 #include <linux/idr.h>
38 #include <linux/backing-dev.h>
39 #include <linux/gfp.h>
40 #include <linux/slab.h>
41 #include <linux/reboot.h>
42 #include <linux/kconfig.h>
44 #include <linux/mtd/mtd.h>
45 #include <linux/mtd/partitions.h>
49 static struct backing_dev_info mtd_bdi
= {
52 #ifdef CONFIG_PM_SLEEP
54 static int mtd_cls_suspend(struct device
*dev
)
56 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
58 return mtd
? mtd_suspend(mtd
) : 0;
61 static int mtd_cls_resume(struct device
*dev
)
63 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
70 static SIMPLE_DEV_PM_OPS(mtd_cls_pm_ops
, mtd_cls_suspend
, mtd_cls_resume
);
71 #define MTD_CLS_PM_OPS (&mtd_cls_pm_ops)
73 #define MTD_CLS_PM_OPS NULL
76 static struct class mtd_class
= {
82 static DEFINE_IDR(mtd_idr
);
84 /* These are exported solely for the purpose of mtd_blkdevs.c. You
85 should not use them for _anything_ else */
86 DEFINE_MUTEX(mtd_table_mutex
);
87 EXPORT_SYMBOL_GPL(mtd_table_mutex
);
89 struct mtd_info
*__mtd_next_device(int i
)
91 return idr_get_next(&mtd_idr
, &i
);
93 EXPORT_SYMBOL_GPL(__mtd_next_device
);
95 static LIST_HEAD(mtd_notifiers
);
98 #define MTD_DEVT(index) MKDEV(MTD_CHAR_MAJOR, (index)*2)
100 /* REVISIT once MTD uses the driver model better, whoever allocates
101 * the mtd_info will probably want to use the release() hook...
103 static void mtd_release(struct device
*dev
)
105 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
106 dev_t index
= MTD_DEVT(mtd
->index
);
108 /* remove /dev/mtdXro node */
109 device_destroy(&mtd_class
, index
+ 1);
112 static ssize_t
mtd_type_show(struct device
*dev
,
113 struct device_attribute
*attr
, char *buf
)
115 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
140 case MTD_MLCNANDFLASH
:
147 return snprintf(buf
, PAGE_SIZE
, "%s\n", type
);
149 static DEVICE_ATTR(type
, S_IRUGO
, mtd_type_show
, NULL
);
151 static ssize_t
mtd_flags_show(struct device
*dev
,
152 struct device_attribute
*attr
, char *buf
)
154 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
156 return snprintf(buf
, PAGE_SIZE
, "0x%lx\n", (unsigned long)mtd
->flags
);
159 static DEVICE_ATTR(flags
, S_IRUGO
, mtd_flags_show
, NULL
);
161 static ssize_t
mtd_size_show(struct device
*dev
,
162 struct device_attribute
*attr
, char *buf
)
164 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
166 return snprintf(buf
, PAGE_SIZE
, "%llu\n",
167 (unsigned long long)mtd
->size
);
170 static DEVICE_ATTR(size
, S_IRUGO
, mtd_size_show
, NULL
);
172 static ssize_t
mtd_erasesize_show(struct device
*dev
,
173 struct device_attribute
*attr
, char *buf
)
175 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
177 return snprintf(buf
, PAGE_SIZE
, "%lu\n", (unsigned long)mtd
->erasesize
);
180 static DEVICE_ATTR(erasesize
, S_IRUGO
, mtd_erasesize_show
, NULL
);
182 static ssize_t
mtd_writesize_show(struct device
*dev
,
183 struct device_attribute
*attr
, char *buf
)
185 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
187 return snprintf(buf
, PAGE_SIZE
, "%lu\n", (unsigned long)mtd
->writesize
);
190 static DEVICE_ATTR(writesize
, S_IRUGO
, mtd_writesize_show
, NULL
);
192 static ssize_t
mtd_subpagesize_show(struct device
*dev
,
193 struct device_attribute
*attr
, char *buf
)
195 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
196 unsigned int subpagesize
= mtd
->writesize
>> mtd
->subpage_sft
;
198 return snprintf(buf
, PAGE_SIZE
, "%u\n", subpagesize
);
201 static DEVICE_ATTR(subpagesize
, S_IRUGO
, mtd_subpagesize_show
, NULL
);
203 static ssize_t
mtd_oobsize_show(struct device
*dev
,
204 struct device_attribute
*attr
, char *buf
)
206 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
208 return snprintf(buf
, PAGE_SIZE
, "%lu\n", (unsigned long)mtd
->oobsize
);
211 static DEVICE_ATTR(oobsize
, S_IRUGO
, mtd_oobsize_show
, NULL
);
213 static ssize_t
mtd_numeraseregions_show(struct device
*dev
,
214 struct device_attribute
*attr
, char *buf
)
216 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
218 return snprintf(buf
, PAGE_SIZE
, "%u\n", mtd
->numeraseregions
);
221 static DEVICE_ATTR(numeraseregions
, S_IRUGO
, mtd_numeraseregions_show
,
224 static ssize_t
mtd_name_show(struct device
*dev
,
225 struct device_attribute
*attr
, char *buf
)
227 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
229 return snprintf(buf
, PAGE_SIZE
, "%s\n", mtd
->name
);
232 static DEVICE_ATTR(name
, S_IRUGO
, mtd_name_show
, NULL
);
234 static ssize_t
mtd_ecc_strength_show(struct device
*dev
,
235 struct device_attribute
*attr
, char *buf
)
237 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
239 return snprintf(buf
, PAGE_SIZE
, "%u\n", mtd
->ecc_strength
);
241 static DEVICE_ATTR(ecc_strength
, S_IRUGO
, mtd_ecc_strength_show
, NULL
);
243 static ssize_t
mtd_bitflip_threshold_show(struct device
*dev
,
244 struct device_attribute
*attr
,
247 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
249 return snprintf(buf
, PAGE_SIZE
, "%u\n", mtd
->bitflip_threshold
);
252 static ssize_t
mtd_bitflip_threshold_store(struct device
*dev
,
253 struct device_attribute
*attr
,
254 const char *buf
, size_t count
)
256 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
257 unsigned int bitflip_threshold
;
260 retval
= kstrtouint(buf
, 0, &bitflip_threshold
);
264 mtd
->bitflip_threshold
= bitflip_threshold
;
267 static DEVICE_ATTR(bitflip_threshold
, S_IRUGO
| S_IWUSR
,
268 mtd_bitflip_threshold_show
,
269 mtd_bitflip_threshold_store
);
271 static ssize_t
mtd_ecc_step_size_show(struct device
*dev
,
272 struct device_attribute
*attr
, char *buf
)
274 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
276 return snprintf(buf
, PAGE_SIZE
, "%u\n", mtd
->ecc_step_size
);
279 static DEVICE_ATTR(ecc_step_size
, S_IRUGO
, mtd_ecc_step_size_show
, NULL
);
281 static ssize_t
mtd_ecc_stats_corrected_show(struct device
*dev
,
282 struct device_attribute
*attr
, char *buf
)
284 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
285 struct mtd_ecc_stats
*ecc_stats
= &mtd
->ecc_stats
;
287 return snprintf(buf
, PAGE_SIZE
, "%u\n", ecc_stats
->corrected
);
289 static DEVICE_ATTR(corrected_bits
, S_IRUGO
,
290 mtd_ecc_stats_corrected_show
, NULL
);
292 static ssize_t
mtd_ecc_stats_errors_show(struct device
*dev
,
293 struct device_attribute
*attr
, char *buf
)
295 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
296 struct mtd_ecc_stats
*ecc_stats
= &mtd
->ecc_stats
;
298 return snprintf(buf
, PAGE_SIZE
, "%u\n", ecc_stats
->failed
);
300 static DEVICE_ATTR(ecc_failures
, S_IRUGO
, mtd_ecc_stats_errors_show
, NULL
);
302 static ssize_t
mtd_badblocks_show(struct device
*dev
,
303 struct device_attribute
*attr
, char *buf
)
305 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
306 struct mtd_ecc_stats
*ecc_stats
= &mtd
->ecc_stats
;
308 return snprintf(buf
, PAGE_SIZE
, "%u\n", ecc_stats
->badblocks
);
310 static DEVICE_ATTR(bad_blocks
, S_IRUGO
, mtd_badblocks_show
, NULL
);
312 static ssize_t
mtd_bbtblocks_show(struct device
*dev
,
313 struct device_attribute
*attr
, char *buf
)
315 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
316 struct mtd_ecc_stats
*ecc_stats
= &mtd
->ecc_stats
;
318 return snprintf(buf
, PAGE_SIZE
, "%u\n", ecc_stats
->bbtblocks
);
320 static DEVICE_ATTR(bbt_blocks
, S_IRUGO
, mtd_bbtblocks_show
, NULL
);
322 static struct attribute
*mtd_attrs
[] = {
324 &dev_attr_flags
.attr
,
326 &dev_attr_erasesize
.attr
,
327 &dev_attr_writesize
.attr
,
328 &dev_attr_subpagesize
.attr
,
329 &dev_attr_oobsize
.attr
,
330 &dev_attr_numeraseregions
.attr
,
332 &dev_attr_ecc_strength
.attr
,
333 &dev_attr_ecc_step_size
.attr
,
334 &dev_attr_corrected_bits
.attr
,
335 &dev_attr_ecc_failures
.attr
,
336 &dev_attr_bad_blocks
.attr
,
337 &dev_attr_bbt_blocks
.attr
,
338 &dev_attr_bitflip_threshold
.attr
,
341 ATTRIBUTE_GROUPS(mtd
);
343 static struct device_type mtd_devtype
= {
345 .groups
= mtd_groups
,
346 .release
= mtd_release
,
350 unsigned mtd_mmap_capabilities(struct mtd_info
*mtd
)
354 return NOMMU_MAP_COPY
| NOMMU_MAP_DIRECT
| NOMMU_MAP_EXEC
|
355 NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
357 return NOMMU_MAP_COPY
| NOMMU_MAP_DIRECT
| NOMMU_MAP_EXEC
|
360 return NOMMU_MAP_COPY
;
363 EXPORT_SYMBOL_GPL(mtd_mmap_capabilities
);
366 static int mtd_reboot_notifier(struct notifier_block
*n
, unsigned long state
,
369 struct mtd_info
*mtd
;
371 mtd
= container_of(n
, struct mtd_info
, reboot_notifier
);
378 * add_mtd_device - register an MTD device
379 * @mtd: pointer to new MTD device info structure
381 * Add a device to the list of MTD devices present in the system, and
382 * notify each currently active MTD 'user' of its arrival. Returns
383 * zero on success or non-zero on failure.
386 int add_mtd_device(struct mtd_info
*mtd
)
388 struct mtd_notifier
*not;
392 * May occur, for instance, on buggy drivers which call
393 * mtd_device_parse_register() multiple times on the same master MTD,
394 * especially with CONFIG_MTD_PARTITIONED_MASTER=y.
396 if (WARN_ONCE(mtd
->backing_dev_info
, "MTD already registered\n"))
399 mtd
->backing_dev_info
= &mtd_bdi
;
401 BUG_ON(mtd
->writesize
== 0);
402 mutex_lock(&mtd_table_mutex
);
404 i
= idr_alloc(&mtd_idr
, mtd
, 0, 0, GFP_KERNEL
);
413 /* default value if not set by driver */
414 if (mtd
->bitflip_threshold
== 0)
415 mtd
->bitflip_threshold
= mtd
->ecc_strength
;
417 if (is_power_of_2(mtd
->erasesize
))
418 mtd
->erasesize_shift
= ffs(mtd
->erasesize
) - 1;
420 mtd
->erasesize_shift
= 0;
422 if (is_power_of_2(mtd
->writesize
))
423 mtd
->writesize_shift
= ffs(mtd
->writesize
) - 1;
425 mtd
->writesize_shift
= 0;
427 mtd
->erasesize_mask
= (1 << mtd
->erasesize_shift
) - 1;
428 mtd
->writesize_mask
= (1 << mtd
->writesize_shift
) - 1;
430 if (mtd
->dev
.parent
) {
431 if (!mtd
->owner
&& mtd
->dev
.parent
->driver
)
432 mtd
->owner
= mtd
->dev
.parent
->driver
->owner
;
434 mtd
->name
= dev_name(mtd
->dev
.parent
);
436 pr_debug("mtd device won't show a device symlink in sysfs\n");
439 /* Some chips always power up locked. Unlock them now */
440 if ((mtd
->flags
& MTD_WRITEABLE
) && (mtd
->flags
& MTD_POWERUP_LOCK
)) {
441 error
= mtd_unlock(mtd
, 0, mtd
->size
);
442 if (error
&& error
!= -EOPNOTSUPP
)
444 "%s: unlock failed, writes may not work\n",
446 /* Ignore unlock failures? */
450 /* Caller should have set dev.parent to match the
451 * physical device, if appropriate.
453 mtd
->dev
.type
= &mtd_devtype
;
454 mtd
->dev
.class = &mtd_class
;
455 mtd
->dev
.devt
= MTD_DEVT(i
);
456 dev_set_name(&mtd
->dev
, "mtd%d", i
);
457 dev_set_drvdata(&mtd
->dev
, mtd
);
458 of_node_get(mtd_get_of_node(mtd
));
459 error
= device_register(&mtd
->dev
);
463 device_create(&mtd_class
, mtd
->dev
.parent
, MTD_DEVT(i
) + 1, NULL
,
466 pr_debug("mtd: Giving out device %d to %s\n", i
, mtd
->name
);
467 /* No need to get a refcount on the module containing
468 the notifier, since we hold the mtd_table_mutex */
469 list_for_each_entry(not, &mtd_notifiers
, list
)
472 mutex_unlock(&mtd_table_mutex
);
473 /* We _know_ we aren't being removed, because
474 our caller is still holding us here. So none
475 of this try_ nonsense, and no bitching about it
477 __module_get(THIS_MODULE
);
481 of_node_put(mtd_get_of_node(mtd
));
482 idr_remove(&mtd_idr
, i
);
484 mutex_unlock(&mtd_table_mutex
);
489 * del_mtd_device - unregister an MTD device
490 * @mtd: pointer to MTD device info structure
492 * Remove a device from the list of MTD devices present in the system,
493 * and notify each currently active MTD 'user' of its departure.
494 * Returns zero on success or 1 on failure, which currently will happen
495 * if the requested device does not appear to be present in the list.
498 int del_mtd_device(struct mtd_info
*mtd
)
501 struct mtd_notifier
*not;
503 mutex_lock(&mtd_table_mutex
);
505 if (idr_find(&mtd_idr
, mtd
->index
) != mtd
) {
510 /* No need to get a refcount on the module containing
511 the notifier, since we hold the mtd_table_mutex */
512 list_for_each_entry(not, &mtd_notifiers
, list
)
516 printk(KERN_NOTICE
"Removing MTD device #%d (%s) with use count %d\n",
517 mtd
->index
, mtd
->name
, mtd
->usecount
);
520 device_unregister(&mtd
->dev
);
522 idr_remove(&mtd_idr
, mtd
->index
);
523 of_node_put(mtd_get_of_node(mtd
));
525 module_put(THIS_MODULE
);
530 mutex_unlock(&mtd_table_mutex
);
534 static int mtd_add_device_partitions(struct mtd_info
*mtd
,
535 struct mtd_partition
*real_parts
,
540 if (nbparts
== 0 || IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER
)) {
541 ret
= add_mtd_device(mtd
);
547 ret
= add_mtd_partitions(mtd
, real_parts
, nbparts
);
548 if (ret
&& IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER
))
558 * mtd_device_parse_register - parse partitions and register an MTD device.
560 * @mtd: the MTD device to register
561 * @types: the list of MTD partition probes to try, see
562 * 'parse_mtd_partitions()' for more information
563 * @parser_data: MTD partition parser-specific data
564 * @parts: fallback partition information to register, if parsing fails;
565 * only valid if %nr_parts > %0
566 * @nr_parts: the number of partitions in parts, if zero then the full
567 * MTD device is registered if no partition info is found
569 * This function aggregates MTD partitions parsing (done by
570 * 'parse_mtd_partitions()') and MTD device and partitions registering. It
571 * basically follows the most common pattern found in many MTD drivers:
573 * * It first tries to probe partitions on MTD device @mtd using parsers
574 * specified in @types (if @types is %NULL, then the default list of parsers
575 * is used, see 'parse_mtd_partitions()' for more information). If none are
576 * found this functions tries to fallback to information specified in
578 * * If any partitioning info was found, this function registers the found
579 * partitions. If the MTD_PARTITIONED_MASTER option is set, then the device
580 * as a whole is registered first.
581 * * If no partitions were found this function just registers the MTD device
584 * Returns zero in case of success and a negative error code in case of failure.
586 int mtd_device_parse_register(struct mtd_info
*mtd
, const char * const *types
,
587 struct mtd_part_parser_data
*parser_data
,
588 const struct mtd_partition
*parts
,
592 struct mtd_partition
*real_parts
= NULL
;
594 ret
= parse_mtd_partitions(mtd
, types
, &real_parts
, parser_data
);
595 if (ret
<= 0 && nr_parts
&& parts
) {
596 real_parts
= kmemdup(parts
, sizeof(*parts
) * nr_parts
,
603 /* Didn't come up with either parsed OR fallback partitions */
605 pr_info("mtd: failed to find partitions; one or more parsers reports errors (%d)\n",
607 /* Don't abort on errors; we can still use unpartitioned MTD */
611 ret
= mtd_add_device_partitions(mtd
, real_parts
, ret
);
616 * FIXME: some drivers unfortunately call this function more than once.
617 * So we have to check if we've already assigned the reboot notifier.
619 * Generally, we can make multiple calls work for most cases, but it
620 * does cause problems with parse_mtd_partitions() above (e.g.,
621 * cmdlineparts will register partitions more than once).
623 WARN_ONCE(mtd
->_reboot
&& mtd
->reboot_notifier
.notifier_call
,
624 "MTD already registered\n");
625 if (mtd
->_reboot
&& !mtd
->reboot_notifier
.notifier_call
) {
626 mtd
->reboot_notifier
.notifier_call
= mtd_reboot_notifier
;
627 register_reboot_notifier(&mtd
->reboot_notifier
);
634 EXPORT_SYMBOL_GPL(mtd_device_parse_register
);
637 * mtd_device_unregister - unregister an existing MTD device.
639 * @master: the MTD device to unregister. This will unregister both the master
640 * and any partitions if registered.
642 int mtd_device_unregister(struct mtd_info
*master
)
647 unregister_reboot_notifier(&master
->reboot_notifier
);
649 err
= del_mtd_partitions(master
);
653 if (!device_is_registered(&master
->dev
))
656 return del_mtd_device(master
);
658 EXPORT_SYMBOL_GPL(mtd_device_unregister
);
661 * register_mtd_user - register a 'user' of MTD devices.
662 * @new: pointer to notifier info structure
664 * Registers a pair of callbacks function to be called upon addition
665 * or removal of MTD devices. Causes the 'add' callback to be immediately
666 * invoked for each MTD device currently present in the system.
668 void register_mtd_user (struct mtd_notifier
*new)
670 struct mtd_info
*mtd
;
672 mutex_lock(&mtd_table_mutex
);
674 list_add(&new->list
, &mtd_notifiers
);
676 __module_get(THIS_MODULE
);
678 mtd_for_each_device(mtd
)
681 mutex_unlock(&mtd_table_mutex
);
683 EXPORT_SYMBOL_GPL(register_mtd_user
);
686 * unregister_mtd_user - unregister a 'user' of MTD devices.
687 * @old: pointer to notifier info structure
689 * Removes a callback function pair from the list of 'users' to be
690 * notified upon addition or removal of MTD devices. Causes the
691 * 'remove' callback to be immediately invoked for each MTD device
692 * currently present in the system.
694 int unregister_mtd_user (struct mtd_notifier
*old
)
696 struct mtd_info
*mtd
;
698 mutex_lock(&mtd_table_mutex
);
700 module_put(THIS_MODULE
);
702 mtd_for_each_device(mtd
)
705 list_del(&old
->list
);
706 mutex_unlock(&mtd_table_mutex
);
709 EXPORT_SYMBOL_GPL(unregister_mtd_user
);
712 * get_mtd_device - obtain a validated handle for an MTD device
713 * @mtd: last known address of the required MTD device
714 * @num: internal device number of the required MTD device
716 * Given a number and NULL address, return the num'th entry in the device
717 * table, if any. Given an address and num == -1, search the device table
718 * for a device with that address and return if it's still present. Given
719 * both, return the num'th driver only if its address matches. Return
722 struct mtd_info
*get_mtd_device(struct mtd_info
*mtd
, int num
)
724 struct mtd_info
*ret
= NULL
, *other
;
727 mutex_lock(&mtd_table_mutex
);
730 mtd_for_each_device(other
) {
736 } else if (num
>= 0) {
737 ret
= idr_find(&mtd_idr
, num
);
738 if (mtd
&& mtd
!= ret
)
747 err
= __get_mtd_device(ret
);
751 mutex_unlock(&mtd_table_mutex
);
754 EXPORT_SYMBOL_GPL(get_mtd_device
);
757 int __get_mtd_device(struct mtd_info
*mtd
)
761 if (!try_module_get(mtd
->owner
))
764 if (mtd
->_get_device
) {
765 err
= mtd
->_get_device(mtd
);
768 module_put(mtd
->owner
);
775 EXPORT_SYMBOL_GPL(__get_mtd_device
);
778 * get_mtd_device_nm - obtain a validated handle for an MTD device by
780 * @name: MTD device name to open
782 * This function returns MTD device description structure in case of
783 * success and an error code in case of failure.
785 struct mtd_info
*get_mtd_device_nm(const char *name
)
788 struct mtd_info
*mtd
= NULL
, *other
;
790 mutex_lock(&mtd_table_mutex
);
792 mtd_for_each_device(other
) {
793 if (!strcmp(name
, other
->name
)) {
802 err
= __get_mtd_device(mtd
);
806 mutex_unlock(&mtd_table_mutex
);
810 mutex_unlock(&mtd_table_mutex
);
813 EXPORT_SYMBOL_GPL(get_mtd_device_nm
);
815 void put_mtd_device(struct mtd_info
*mtd
)
817 mutex_lock(&mtd_table_mutex
);
818 __put_mtd_device(mtd
);
819 mutex_unlock(&mtd_table_mutex
);
822 EXPORT_SYMBOL_GPL(put_mtd_device
);
824 void __put_mtd_device(struct mtd_info
*mtd
)
827 BUG_ON(mtd
->usecount
< 0);
829 if (mtd
->_put_device
)
830 mtd
->_put_device(mtd
);
832 module_put(mtd
->owner
);
834 EXPORT_SYMBOL_GPL(__put_mtd_device
);
837 * Erase is an asynchronous operation. Device drivers are supposed
838 * to call instr->callback() whenever the operation completes, even
839 * if it completes with a failure.
840 * Callers are supposed to pass a callback function and wait for it
841 * to be called before writing to the block.
843 int mtd_erase(struct mtd_info
*mtd
, struct erase_info
*instr
)
845 if (instr
->addr
>= mtd
->size
|| instr
->len
> mtd
->size
- instr
->addr
)
847 if (!(mtd
->flags
& MTD_WRITEABLE
))
849 instr
->fail_addr
= MTD_FAIL_ADDR_UNKNOWN
;
851 instr
->state
= MTD_ERASE_DONE
;
852 mtd_erase_callback(instr
);
855 return mtd
->_erase(mtd
, instr
);
857 EXPORT_SYMBOL_GPL(mtd_erase
);
860 * This stuff for eXecute-In-Place. phys is optional and may be set to NULL.
862 int mtd_point(struct mtd_info
*mtd
, loff_t from
, size_t len
, size_t *retlen
,
863 void **virt
, resource_size_t
*phys
)
871 if (from
< 0 || from
>= mtd
->size
|| len
> mtd
->size
- from
)
875 return mtd
->_point(mtd
, from
, len
, retlen
, virt
, phys
);
877 EXPORT_SYMBOL_GPL(mtd_point
);
879 /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
880 int mtd_unpoint(struct mtd_info
*mtd
, loff_t from
, size_t len
)
884 if (from
< 0 || from
>= mtd
->size
|| len
> mtd
->size
- from
)
888 return mtd
->_unpoint(mtd
, from
, len
);
890 EXPORT_SYMBOL_GPL(mtd_unpoint
);
893 * Allow NOMMU mmap() to directly map the device (if not NULL)
894 * - return the address to which the offset maps
895 * - return -ENOSYS to indicate refusal to do the mapping
897 unsigned long mtd_get_unmapped_area(struct mtd_info
*mtd
, unsigned long len
,
898 unsigned long offset
, unsigned long flags
)
900 if (!mtd
->_get_unmapped_area
)
902 if (offset
>= mtd
->size
|| len
> mtd
->size
- offset
)
904 return mtd
->_get_unmapped_area(mtd
, len
, offset
, flags
);
906 EXPORT_SYMBOL_GPL(mtd_get_unmapped_area
);
908 int mtd_read(struct mtd_info
*mtd
, loff_t from
, size_t len
, size_t *retlen
,
913 if (from
< 0 || from
>= mtd
->size
|| len
> mtd
->size
- from
)
919 * In the absence of an error, drivers return a non-negative integer
920 * representing the maximum number of bitflips that were corrected on
921 * any one ecc region (if applicable; zero otherwise).
923 ret_code
= mtd
->_read(mtd
, from
, len
, retlen
, buf
);
924 if (unlikely(ret_code
< 0))
926 if (mtd
->ecc_strength
== 0)
927 return 0; /* device lacks ecc */
928 return ret_code
>= mtd
->bitflip_threshold
? -EUCLEAN
: 0;
930 EXPORT_SYMBOL_GPL(mtd_read
);
932 int mtd_write(struct mtd_info
*mtd
, loff_t to
, size_t len
, size_t *retlen
,
936 if (to
< 0 || to
>= mtd
->size
|| len
> mtd
->size
- to
)
938 if (!mtd
->_write
|| !(mtd
->flags
& MTD_WRITEABLE
))
942 return mtd
->_write(mtd
, to
, len
, retlen
, buf
);
944 EXPORT_SYMBOL_GPL(mtd_write
);
947 * In blackbox flight recorder like scenarios we want to make successful writes
948 * in interrupt context. panic_write() is only intended to be called when its
949 * known the kernel is about to panic and we need the write to succeed. Since
950 * the kernel is not going to be running for much longer, this function can
951 * break locks and delay to ensure the write succeeds (but not sleep).
953 int mtd_panic_write(struct mtd_info
*mtd
, loff_t to
, size_t len
, size_t *retlen
,
957 if (!mtd
->_panic_write
)
959 if (to
< 0 || to
>= mtd
->size
|| len
> mtd
->size
- to
)
961 if (!(mtd
->flags
& MTD_WRITEABLE
))
965 return mtd
->_panic_write(mtd
, to
, len
, retlen
, buf
);
967 EXPORT_SYMBOL_GPL(mtd_panic_write
);
969 int mtd_read_oob(struct mtd_info
*mtd
, loff_t from
, struct mtd_oob_ops
*ops
)
972 ops
->retlen
= ops
->oobretlen
= 0;
976 * In cases where ops->datbuf != NULL, mtd->_read_oob() has semantics
977 * similar to mtd->_read(), returning a non-negative integer
978 * representing max bitflips. In other cases, mtd->_read_oob() may
979 * return -EUCLEAN. In all cases, perform similar logic to mtd_read().
981 ret_code
= mtd
->_read_oob(mtd
, from
, ops
);
982 if (unlikely(ret_code
< 0))
984 if (mtd
->ecc_strength
== 0)
985 return 0; /* device lacks ecc */
986 return ret_code
>= mtd
->bitflip_threshold
? -EUCLEAN
: 0;
988 EXPORT_SYMBOL_GPL(mtd_read_oob
);
991 * Method to access the protection register area, present in some flash
992 * devices. The user data is one time programmable but the factory data is read
995 int mtd_get_fact_prot_info(struct mtd_info
*mtd
, size_t len
, size_t *retlen
,
996 struct otp_info
*buf
)
998 if (!mtd
->_get_fact_prot_info
)
1002 return mtd
->_get_fact_prot_info(mtd
, len
, retlen
, buf
);
1004 EXPORT_SYMBOL_GPL(mtd_get_fact_prot_info
);
1006 int mtd_read_fact_prot_reg(struct mtd_info
*mtd
, loff_t from
, size_t len
,
1007 size_t *retlen
, u_char
*buf
)
1010 if (!mtd
->_read_fact_prot_reg
)
1014 return mtd
->_read_fact_prot_reg(mtd
, from
, len
, retlen
, buf
);
1016 EXPORT_SYMBOL_GPL(mtd_read_fact_prot_reg
);
1018 int mtd_get_user_prot_info(struct mtd_info
*mtd
, size_t len
, size_t *retlen
,
1019 struct otp_info
*buf
)
1021 if (!mtd
->_get_user_prot_info
)
1025 return mtd
->_get_user_prot_info(mtd
, len
, retlen
, buf
);
1027 EXPORT_SYMBOL_GPL(mtd_get_user_prot_info
);
1029 int mtd_read_user_prot_reg(struct mtd_info
*mtd
, loff_t from
, size_t len
,
1030 size_t *retlen
, u_char
*buf
)
1033 if (!mtd
->_read_user_prot_reg
)
1037 return mtd
->_read_user_prot_reg(mtd
, from
, len
, retlen
, buf
);
1039 EXPORT_SYMBOL_GPL(mtd_read_user_prot_reg
);
1041 int mtd_write_user_prot_reg(struct mtd_info
*mtd
, loff_t to
, size_t len
,
1042 size_t *retlen
, u_char
*buf
)
1047 if (!mtd
->_write_user_prot_reg
)
1051 ret
= mtd
->_write_user_prot_reg(mtd
, to
, len
, retlen
, buf
);
1056 * If no data could be written at all, we are out of memory and
1057 * must return -ENOSPC.
1059 return (*retlen
) ? 0 : -ENOSPC
;
1061 EXPORT_SYMBOL_GPL(mtd_write_user_prot_reg
);
1063 int mtd_lock_user_prot_reg(struct mtd_info
*mtd
, loff_t from
, size_t len
)
1065 if (!mtd
->_lock_user_prot_reg
)
1069 return mtd
->_lock_user_prot_reg(mtd
, from
, len
);
1071 EXPORT_SYMBOL_GPL(mtd_lock_user_prot_reg
);
1073 /* Chip-supported device locking */
1074 int mtd_lock(struct mtd_info
*mtd
, loff_t ofs
, uint64_t len
)
1078 if (ofs
< 0 || ofs
>= mtd
->size
|| len
> mtd
->size
- ofs
)
1082 return mtd
->_lock(mtd
, ofs
, len
);
1084 EXPORT_SYMBOL_GPL(mtd_lock
);
1086 int mtd_unlock(struct mtd_info
*mtd
, loff_t ofs
, uint64_t len
)
1090 if (ofs
< 0 || ofs
>= mtd
->size
|| len
> mtd
->size
- ofs
)
1094 return mtd
->_unlock(mtd
, ofs
, len
);
1096 EXPORT_SYMBOL_GPL(mtd_unlock
);
1098 int mtd_is_locked(struct mtd_info
*mtd
, loff_t ofs
, uint64_t len
)
1100 if (!mtd
->_is_locked
)
1102 if (ofs
< 0 || ofs
>= mtd
->size
|| len
> mtd
->size
- ofs
)
1106 return mtd
->_is_locked(mtd
, ofs
, len
);
1108 EXPORT_SYMBOL_GPL(mtd_is_locked
);
1110 int mtd_block_isreserved(struct mtd_info
*mtd
, loff_t ofs
)
1112 if (ofs
< 0 || ofs
>= mtd
->size
)
1114 if (!mtd
->_block_isreserved
)
1116 return mtd
->_block_isreserved(mtd
, ofs
);
1118 EXPORT_SYMBOL_GPL(mtd_block_isreserved
);
1120 int mtd_block_isbad(struct mtd_info
*mtd
, loff_t ofs
)
1122 if (ofs
< 0 || ofs
>= mtd
->size
)
1124 if (!mtd
->_block_isbad
)
1126 return mtd
->_block_isbad(mtd
, ofs
);
1128 EXPORT_SYMBOL_GPL(mtd_block_isbad
);
1130 int mtd_block_markbad(struct mtd_info
*mtd
, loff_t ofs
)
1132 if (!mtd
->_block_markbad
)
1134 if (ofs
< 0 || ofs
>= mtd
->size
)
1136 if (!(mtd
->flags
& MTD_WRITEABLE
))
1138 return mtd
->_block_markbad(mtd
, ofs
);
1140 EXPORT_SYMBOL_GPL(mtd_block_markbad
);
1143 * default_mtd_writev - the default writev method
1144 * @mtd: mtd device description object pointer
1145 * @vecs: the vectors to write
1146 * @count: count of vectors in @vecs
1147 * @to: the MTD device offset to write to
1148 * @retlen: on exit contains the count of bytes written to the MTD device.
1150 * This function returns zero in case of success and a negative error code in
1153 static int default_mtd_writev(struct mtd_info
*mtd
, const struct kvec
*vecs
,
1154 unsigned long count
, loff_t to
, size_t *retlen
)
1157 size_t totlen
= 0, thislen
;
1160 for (i
= 0; i
< count
; i
++) {
1161 if (!vecs
[i
].iov_len
)
1163 ret
= mtd_write(mtd
, to
, vecs
[i
].iov_len
, &thislen
,
1166 if (ret
|| thislen
!= vecs
[i
].iov_len
)
1168 to
+= vecs
[i
].iov_len
;
1175 * mtd_writev - the vector-based MTD write method
1176 * @mtd: mtd device description object pointer
1177 * @vecs: the vectors to write
1178 * @count: count of vectors in @vecs
1179 * @to: the MTD device offset to write to
1180 * @retlen: on exit contains the count of bytes written to the MTD device.
1182 * This function returns zero in case of success and a negative error code in
1185 int mtd_writev(struct mtd_info
*mtd
, const struct kvec
*vecs
,
1186 unsigned long count
, loff_t to
, size_t *retlen
)
1189 if (!(mtd
->flags
& MTD_WRITEABLE
))
1192 return default_mtd_writev(mtd
, vecs
, count
, to
, retlen
);
1193 return mtd
->_writev(mtd
, vecs
, count
, to
, retlen
);
1195 EXPORT_SYMBOL_GPL(mtd_writev
);
1198 * mtd_kmalloc_up_to - allocate a contiguous buffer up to the specified size
1199 * @mtd: mtd device description object pointer
1200 * @size: a pointer to the ideal or maximum size of the allocation, points
1201 * to the actual allocation size on success.
1203 * This routine attempts to allocate a contiguous kernel buffer up to
1204 * the specified size, backing off the size of the request exponentially
1205 * until the request succeeds or until the allocation size falls below
1206 * the system page size. This attempts to make sure it does not adversely
1207 * impact system performance, so when allocating more than one page, we
1208 * ask the memory allocator to avoid re-trying, swapping, writing back
1209 * or performing I/O.
1211 * Note, this function also makes sure that the allocated buffer is aligned to
1212 * the MTD device's min. I/O unit, i.e. the "mtd->writesize" value.
1214 * This is called, for example by mtd_{read,write} and jffs2_scan_medium,
1215 * to handle smaller (i.e. degraded) buffer allocations under low- or
1216 * fragmented-memory situations where such reduced allocations, from a
1217 * requested ideal, are allowed.
1219 * Returns a pointer to the allocated buffer on success; otherwise, NULL.
1221 void *mtd_kmalloc_up_to(const struct mtd_info
*mtd
, size_t *size
)
1223 gfp_t flags
= __GFP_NOWARN
| __GFP_DIRECT_RECLAIM
| __GFP_NORETRY
;
1224 size_t min_alloc
= max_t(size_t, mtd
->writesize
, PAGE_SIZE
);
1227 *size
= min_t(size_t, *size
, KMALLOC_MAX_SIZE
);
1229 while (*size
> min_alloc
) {
1230 kbuf
= kmalloc(*size
, flags
);
1235 *size
= ALIGN(*size
, mtd
->writesize
);
1239 * For the last resort allocation allow 'kmalloc()' to do all sorts of
1240 * things (write-back, dropping caches, etc) by using GFP_KERNEL.
1242 return kmalloc(*size
, GFP_KERNEL
);
1244 EXPORT_SYMBOL_GPL(mtd_kmalloc_up_to
);
1246 #ifdef CONFIG_PROC_FS
1248 /*====================================================================*/
1249 /* Support for /proc/mtd */
1251 static int mtd_proc_show(struct seq_file
*m
, void *v
)
1253 struct mtd_info
*mtd
;
1255 seq_puts(m
, "dev: size erasesize name\n");
1256 mutex_lock(&mtd_table_mutex
);
1257 mtd_for_each_device(mtd
) {
1258 seq_printf(m
, "mtd%d: %8.8llx %8.8x \"%s\"\n",
1259 mtd
->index
, (unsigned long long)mtd
->size
,
1260 mtd
->erasesize
, mtd
->name
);
1262 mutex_unlock(&mtd_table_mutex
);
1266 static int mtd_proc_open(struct inode
*inode
, struct file
*file
)
1268 return single_open(file
, mtd_proc_show
, NULL
);
1271 static const struct file_operations mtd_proc_ops
= {
1272 .open
= mtd_proc_open
,
1274 .llseek
= seq_lseek
,
1275 .release
= single_release
,
1277 #endif /* CONFIG_PROC_FS */
1279 /*====================================================================*/
1282 static int __init
mtd_bdi_init(struct backing_dev_info
*bdi
, const char *name
)
1286 ret
= bdi_init(bdi
);
1288 ret
= bdi_register(bdi
, NULL
, "%s", name
);
1296 static struct proc_dir_entry
*proc_mtd
;
1298 static int __init
init_mtd(void)
1302 ret
= class_register(&mtd_class
);
1306 ret
= mtd_bdi_init(&mtd_bdi
, "mtd");
1310 proc_mtd
= proc_create("mtd", 0, NULL
, &mtd_proc_ops
);
1312 ret
= init_mtdchar();
1320 remove_proc_entry("mtd", NULL
);
1322 class_unregister(&mtd_class
);
1324 pr_err("Error registering mtd class or bdi: %d\n", ret
);
1328 static void __exit
cleanup_mtd(void)
1332 remove_proc_entry("mtd", NULL
);
1333 class_unregister(&mtd_class
);
1334 bdi_destroy(&mtd_bdi
);
1335 idr_destroy(&mtd_idr
);
1338 module_init(init_mtd
);
1339 module_exit(cleanup_mtd
);
1341 MODULE_LICENSE("GPL");
1342 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
1343 MODULE_DESCRIPTION("Core MTD registration and access routines");