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/leds.h>
44 #include <linux/mtd/mtd.h>
45 #include <linux/mtd/partitions.h>
49 static struct backing_dev_info
*mtd_bdi
;
51 #ifdef CONFIG_PM_SLEEP
53 static int mtd_cls_suspend(struct device
*dev
)
55 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
57 return mtd
? mtd_suspend(mtd
) : 0;
60 static int mtd_cls_resume(struct device
*dev
)
62 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
69 static SIMPLE_DEV_PM_OPS(mtd_cls_pm_ops
, mtd_cls_suspend
, mtd_cls_resume
);
70 #define MTD_CLS_PM_OPS (&mtd_cls_pm_ops)
72 #define MTD_CLS_PM_OPS NULL
75 static struct class mtd_class
= {
81 static DEFINE_IDR(mtd_idr
);
83 /* These are exported solely for the purpose of mtd_blkdevs.c. You
84 should not use them for _anything_ else */
85 DEFINE_MUTEX(mtd_table_mutex
);
86 EXPORT_SYMBOL_GPL(mtd_table_mutex
);
88 struct mtd_info
*__mtd_next_device(int i
)
90 return idr_get_next(&mtd_idr
, &i
);
92 EXPORT_SYMBOL_GPL(__mtd_next_device
);
94 static LIST_HEAD(mtd_notifiers
);
97 #define MTD_DEVT(index) MKDEV(MTD_CHAR_MAJOR, (index)*2)
99 /* REVISIT once MTD uses the driver model better, whoever allocates
100 * the mtd_info will probably want to use the release() hook...
102 static void mtd_release(struct device
*dev
)
104 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
105 dev_t index
= MTD_DEVT(mtd
->index
);
107 /* remove /dev/mtdXro node */
108 device_destroy(&mtd_class
, index
+ 1);
111 static ssize_t
mtd_type_show(struct device
*dev
,
112 struct device_attribute
*attr
, char *buf
)
114 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
139 case MTD_MLCNANDFLASH
:
146 return snprintf(buf
, PAGE_SIZE
, "%s\n", type
);
148 static DEVICE_ATTR(type
, S_IRUGO
, mtd_type_show
, NULL
);
150 static ssize_t
mtd_flags_show(struct device
*dev
,
151 struct device_attribute
*attr
, char *buf
)
153 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
155 return snprintf(buf
, PAGE_SIZE
, "0x%lx\n", (unsigned long)mtd
->flags
);
158 static DEVICE_ATTR(flags
, S_IRUGO
, mtd_flags_show
, NULL
);
160 static ssize_t
mtd_size_show(struct device
*dev
,
161 struct device_attribute
*attr
, char *buf
)
163 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
165 return snprintf(buf
, PAGE_SIZE
, "%llu\n",
166 (unsigned long long)mtd
->size
);
169 static DEVICE_ATTR(size
, S_IRUGO
, mtd_size_show
, NULL
);
171 static ssize_t
mtd_erasesize_show(struct device
*dev
,
172 struct device_attribute
*attr
, char *buf
)
174 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
176 return snprintf(buf
, PAGE_SIZE
, "%lu\n", (unsigned long)mtd
->erasesize
);
179 static DEVICE_ATTR(erasesize
, S_IRUGO
, mtd_erasesize_show
, NULL
);
181 static ssize_t
mtd_writesize_show(struct device
*dev
,
182 struct device_attribute
*attr
, char *buf
)
184 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
186 return snprintf(buf
, PAGE_SIZE
, "%lu\n", (unsigned long)mtd
->writesize
);
189 static DEVICE_ATTR(writesize
, S_IRUGO
, mtd_writesize_show
, NULL
);
191 static ssize_t
mtd_subpagesize_show(struct device
*dev
,
192 struct device_attribute
*attr
, char *buf
)
194 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
195 unsigned int subpagesize
= mtd
->writesize
>> mtd
->subpage_sft
;
197 return snprintf(buf
, PAGE_SIZE
, "%u\n", subpagesize
);
200 static DEVICE_ATTR(subpagesize
, S_IRUGO
, mtd_subpagesize_show
, NULL
);
202 static ssize_t
mtd_oobsize_show(struct device
*dev
,
203 struct device_attribute
*attr
, char *buf
)
205 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
207 return snprintf(buf
, PAGE_SIZE
, "%lu\n", (unsigned long)mtd
->oobsize
);
210 static DEVICE_ATTR(oobsize
, S_IRUGO
, mtd_oobsize_show
, NULL
);
212 static ssize_t
mtd_numeraseregions_show(struct device
*dev
,
213 struct device_attribute
*attr
, char *buf
)
215 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
217 return snprintf(buf
, PAGE_SIZE
, "%u\n", mtd
->numeraseregions
);
220 static DEVICE_ATTR(numeraseregions
, S_IRUGO
, mtd_numeraseregions_show
,
223 static ssize_t
mtd_name_show(struct device
*dev
,
224 struct device_attribute
*attr
, char *buf
)
226 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
228 return snprintf(buf
, PAGE_SIZE
, "%s\n", mtd
->name
);
231 static DEVICE_ATTR(name
, S_IRUGO
, mtd_name_show
, NULL
);
233 static ssize_t
mtd_ecc_strength_show(struct device
*dev
,
234 struct device_attribute
*attr
, char *buf
)
236 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
238 return snprintf(buf
, PAGE_SIZE
, "%u\n", mtd
->ecc_strength
);
240 static DEVICE_ATTR(ecc_strength
, S_IRUGO
, mtd_ecc_strength_show
, NULL
);
242 static ssize_t
mtd_bitflip_threshold_show(struct device
*dev
,
243 struct device_attribute
*attr
,
246 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
248 return snprintf(buf
, PAGE_SIZE
, "%u\n", mtd
->bitflip_threshold
);
251 static ssize_t
mtd_bitflip_threshold_store(struct device
*dev
,
252 struct device_attribute
*attr
,
253 const char *buf
, size_t count
)
255 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
256 unsigned int bitflip_threshold
;
259 retval
= kstrtouint(buf
, 0, &bitflip_threshold
);
263 mtd
->bitflip_threshold
= bitflip_threshold
;
266 static DEVICE_ATTR(bitflip_threshold
, S_IRUGO
| S_IWUSR
,
267 mtd_bitflip_threshold_show
,
268 mtd_bitflip_threshold_store
);
270 static ssize_t
mtd_ecc_step_size_show(struct device
*dev
,
271 struct device_attribute
*attr
, char *buf
)
273 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
275 return snprintf(buf
, PAGE_SIZE
, "%u\n", mtd
->ecc_step_size
);
278 static DEVICE_ATTR(ecc_step_size
, S_IRUGO
, mtd_ecc_step_size_show
, NULL
);
280 static ssize_t
mtd_ecc_stats_corrected_show(struct device
*dev
,
281 struct device_attribute
*attr
, char *buf
)
283 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
284 struct mtd_ecc_stats
*ecc_stats
= &mtd
->ecc_stats
;
286 return snprintf(buf
, PAGE_SIZE
, "%u\n", ecc_stats
->corrected
);
288 static DEVICE_ATTR(corrected_bits
, S_IRUGO
,
289 mtd_ecc_stats_corrected_show
, NULL
);
291 static ssize_t
mtd_ecc_stats_errors_show(struct device
*dev
,
292 struct device_attribute
*attr
, char *buf
)
294 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
295 struct mtd_ecc_stats
*ecc_stats
= &mtd
->ecc_stats
;
297 return snprintf(buf
, PAGE_SIZE
, "%u\n", ecc_stats
->failed
);
299 static DEVICE_ATTR(ecc_failures
, S_IRUGO
, mtd_ecc_stats_errors_show
, NULL
);
301 static ssize_t
mtd_badblocks_show(struct device
*dev
,
302 struct device_attribute
*attr
, char *buf
)
304 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
305 struct mtd_ecc_stats
*ecc_stats
= &mtd
->ecc_stats
;
307 return snprintf(buf
, PAGE_SIZE
, "%u\n", ecc_stats
->badblocks
);
309 static DEVICE_ATTR(bad_blocks
, S_IRUGO
, mtd_badblocks_show
, NULL
);
311 static ssize_t
mtd_bbtblocks_show(struct device
*dev
,
312 struct device_attribute
*attr
, char *buf
)
314 struct mtd_info
*mtd
= dev_get_drvdata(dev
);
315 struct mtd_ecc_stats
*ecc_stats
= &mtd
->ecc_stats
;
317 return snprintf(buf
, PAGE_SIZE
, "%u\n", ecc_stats
->bbtblocks
);
319 static DEVICE_ATTR(bbt_blocks
, S_IRUGO
, mtd_bbtblocks_show
, NULL
);
321 static struct attribute
*mtd_attrs
[] = {
323 &dev_attr_flags
.attr
,
325 &dev_attr_erasesize
.attr
,
326 &dev_attr_writesize
.attr
,
327 &dev_attr_subpagesize
.attr
,
328 &dev_attr_oobsize
.attr
,
329 &dev_attr_numeraseregions
.attr
,
331 &dev_attr_ecc_strength
.attr
,
332 &dev_attr_ecc_step_size
.attr
,
333 &dev_attr_corrected_bits
.attr
,
334 &dev_attr_ecc_failures
.attr
,
335 &dev_attr_bad_blocks
.attr
,
336 &dev_attr_bbt_blocks
.attr
,
337 &dev_attr_bitflip_threshold
.attr
,
340 ATTRIBUTE_GROUPS(mtd
);
342 static struct device_type mtd_devtype
= {
344 .groups
= mtd_groups
,
345 .release
= mtd_release
,
349 unsigned mtd_mmap_capabilities(struct mtd_info
*mtd
)
353 return NOMMU_MAP_COPY
| NOMMU_MAP_DIRECT
| NOMMU_MAP_EXEC
|
354 NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
356 return NOMMU_MAP_COPY
| NOMMU_MAP_DIRECT
| NOMMU_MAP_EXEC
|
359 return NOMMU_MAP_COPY
;
362 EXPORT_SYMBOL_GPL(mtd_mmap_capabilities
);
365 static int mtd_reboot_notifier(struct notifier_block
*n
, unsigned long state
,
368 struct mtd_info
*mtd
;
370 mtd
= container_of(n
, struct mtd_info
, reboot_notifier
);
377 * mtd_wunit_to_pairing_info - get pairing information of a wunit
378 * @mtd: pointer to new MTD device info structure
379 * @wunit: write unit we are interested in
380 * @info: returned pairing information
382 * Retrieve pairing information associated to the wunit.
383 * This is mainly useful when dealing with MLC/TLC NANDs where pages can be
384 * paired together, and where programming a page may influence the page it is
386 * The notion of page is replaced by the term wunit (write-unit) to stay
387 * consistent with the ->writesize field.
389 * The @wunit argument can be extracted from an absolute offset using
390 * mtd_offset_to_wunit(). @info is filled with the pairing information attached
393 * From the pairing info the MTD user can find all the wunits paired with
394 * @wunit using the following loop:
396 * for (i = 0; i < mtd_pairing_groups(mtd); i++) {
398 * mtd_pairing_info_to_wunit(mtd, &info);
402 int mtd_wunit_to_pairing_info(struct mtd_info
*mtd
, int wunit
,
403 struct mtd_pairing_info
*info
)
405 int npairs
= mtd_wunit_per_eb(mtd
) / mtd_pairing_groups(mtd
);
407 if (wunit
< 0 || wunit
>= npairs
)
410 if (mtd
->pairing
&& mtd
->pairing
->get_info
)
411 return mtd
->pairing
->get_info(mtd
, wunit
, info
);
418 EXPORT_SYMBOL_GPL(mtd_wunit_to_pairing_info
);
421 * mtd_wunit_to_pairing_info - get wunit from pairing information
422 * @mtd: pointer to new MTD device info structure
423 * @info: pairing information struct
425 * Returns a positive number representing the wunit associated to the info
426 * struct, or a negative error code.
428 * This is the reverse of mtd_wunit_to_pairing_info(), and can help one to
429 * iterate over all wunits of a given pair (see mtd_wunit_to_pairing_info()
432 * It can also be used to only program the first page of each pair (i.e.
433 * page attached to group 0), which allows one to use an MLC NAND in
434 * software-emulated SLC mode:
437 * npairs = mtd_wunit_per_eb(mtd) / mtd_pairing_groups(mtd);
438 * for (info.pair = 0; info.pair < npairs; info.pair++) {
439 * wunit = mtd_pairing_info_to_wunit(mtd, &info);
440 * mtd_write(mtd, mtd_wunit_to_offset(mtd, blkoffs, wunit),
441 * mtd->writesize, &retlen, buf + (i * mtd->writesize));
444 int mtd_pairing_info_to_wunit(struct mtd_info
*mtd
,
445 const struct mtd_pairing_info
*info
)
447 int ngroups
= mtd_pairing_groups(mtd
);
448 int npairs
= mtd_wunit_per_eb(mtd
) / ngroups
;
450 if (!info
|| info
->pair
< 0 || info
->pair
>= npairs
||
451 info
->group
< 0 || info
->group
>= ngroups
)
454 if (mtd
->pairing
&& mtd
->pairing
->get_wunit
)
455 return mtd
->pairing
->get_wunit(mtd
, info
);
459 EXPORT_SYMBOL_GPL(mtd_pairing_info_to_wunit
);
462 * mtd_pairing_groups - get the number of pairing groups
463 * @mtd: pointer to new MTD device info structure
465 * Returns the number of pairing groups.
467 * This number is usually equal to the number of bits exposed by a single
468 * cell, and can be used in conjunction with mtd_pairing_info_to_wunit()
469 * to iterate over all pages of a given pair.
471 int mtd_pairing_groups(struct mtd_info
*mtd
)
473 if (!mtd
->pairing
|| !mtd
->pairing
->ngroups
)
476 return mtd
->pairing
->ngroups
;
478 EXPORT_SYMBOL_GPL(mtd_pairing_groups
);
481 * add_mtd_device - register an MTD device
482 * @mtd: pointer to new MTD device info structure
484 * Add a device to the list of MTD devices present in the system, and
485 * notify each currently active MTD 'user' of its arrival. Returns
486 * zero on success or non-zero on failure.
489 int add_mtd_device(struct mtd_info
*mtd
)
491 struct mtd_notifier
*not;
495 * May occur, for instance, on buggy drivers which call
496 * mtd_device_parse_register() multiple times on the same master MTD,
497 * especially with CONFIG_MTD_PARTITIONED_MASTER=y.
499 if (WARN_ONCE(mtd
->backing_dev_info
, "MTD already registered\n"))
502 mtd
->backing_dev_info
= mtd_bdi
;
504 BUG_ON(mtd
->writesize
== 0);
505 mutex_lock(&mtd_table_mutex
);
507 i
= idr_alloc(&mtd_idr
, mtd
, 0, 0, GFP_KERNEL
);
516 /* default value if not set by driver */
517 if (mtd
->bitflip_threshold
== 0)
518 mtd
->bitflip_threshold
= mtd
->ecc_strength
;
520 if (is_power_of_2(mtd
->erasesize
))
521 mtd
->erasesize_shift
= ffs(mtd
->erasesize
) - 1;
523 mtd
->erasesize_shift
= 0;
525 if (is_power_of_2(mtd
->writesize
))
526 mtd
->writesize_shift
= ffs(mtd
->writesize
) - 1;
528 mtd
->writesize_shift
= 0;
530 mtd
->erasesize_mask
= (1 << mtd
->erasesize_shift
) - 1;
531 mtd
->writesize_mask
= (1 << mtd
->writesize_shift
) - 1;
533 /* Some chips always power up locked. Unlock them now */
534 if ((mtd
->flags
& MTD_WRITEABLE
) && (mtd
->flags
& MTD_POWERUP_LOCK
)) {
535 error
= mtd_unlock(mtd
, 0, mtd
->size
);
536 if (error
&& error
!= -EOPNOTSUPP
)
538 "%s: unlock failed, writes may not work\n",
540 /* Ignore unlock failures? */
544 /* Caller should have set dev.parent to match the
545 * physical device, if appropriate.
547 mtd
->dev
.type
= &mtd_devtype
;
548 mtd
->dev
.class = &mtd_class
;
549 mtd
->dev
.devt
= MTD_DEVT(i
);
550 dev_set_name(&mtd
->dev
, "mtd%d", i
);
551 dev_set_drvdata(&mtd
->dev
, mtd
);
552 of_node_get(mtd_get_of_node(mtd
));
553 error
= device_register(&mtd
->dev
);
557 device_create(&mtd_class
, mtd
->dev
.parent
, MTD_DEVT(i
) + 1, NULL
,
560 pr_debug("mtd: Giving out device %d to %s\n", i
, mtd
->name
);
561 /* No need to get a refcount on the module containing
562 the notifier, since we hold the mtd_table_mutex */
563 list_for_each_entry(not, &mtd_notifiers
, list
)
566 mutex_unlock(&mtd_table_mutex
);
567 /* We _know_ we aren't being removed, because
568 our caller is still holding us here. So none
569 of this try_ nonsense, and no bitching about it
571 __module_get(THIS_MODULE
);
575 of_node_put(mtd_get_of_node(mtd
));
576 idr_remove(&mtd_idr
, i
);
578 mutex_unlock(&mtd_table_mutex
);
583 * del_mtd_device - unregister an MTD device
584 * @mtd: pointer to MTD device info structure
586 * Remove a device from the list of MTD devices present in the system,
587 * and notify each currently active MTD 'user' of its departure.
588 * Returns zero on success or 1 on failure, which currently will happen
589 * if the requested device does not appear to be present in the list.
592 int del_mtd_device(struct mtd_info
*mtd
)
595 struct mtd_notifier
*not;
597 mutex_lock(&mtd_table_mutex
);
599 if (idr_find(&mtd_idr
, mtd
->index
) != mtd
) {
604 /* No need to get a refcount on the module containing
605 the notifier, since we hold the mtd_table_mutex */
606 list_for_each_entry(not, &mtd_notifiers
, list
)
610 printk(KERN_NOTICE
"Removing MTD device #%d (%s) with use count %d\n",
611 mtd
->index
, mtd
->name
, mtd
->usecount
);
614 device_unregister(&mtd
->dev
);
616 idr_remove(&mtd_idr
, mtd
->index
);
617 of_node_put(mtd_get_of_node(mtd
));
619 module_put(THIS_MODULE
);
624 mutex_unlock(&mtd_table_mutex
);
628 static int mtd_add_device_partitions(struct mtd_info
*mtd
,
629 struct mtd_partitions
*parts
)
631 const struct mtd_partition
*real_parts
= parts
->parts
;
632 int nbparts
= parts
->nr_parts
;
635 if (nbparts
== 0 || IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER
)) {
636 ret
= add_mtd_device(mtd
);
642 ret
= add_mtd_partitions(mtd
, real_parts
, nbparts
);
643 if (ret
&& IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER
))
652 * Set a few defaults based on the parent devices, if not provided by the
655 static void mtd_set_dev_defaults(struct mtd_info
*mtd
)
657 if (mtd
->dev
.parent
) {
658 if (!mtd
->owner
&& mtd
->dev
.parent
->driver
)
659 mtd
->owner
= mtd
->dev
.parent
->driver
->owner
;
661 mtd
->name
= dev_name(mtd
->dev
.parent
);
663 pr_debug("mtd device won't show a device symlink in sysfs\n");
668 * mtd_device_parse_register - parse partitions and register an MTD device.
670 * @mtd: the MTD device to register
671 * @types: the list of MTD partition probes to try, see
672 * 'parse_mtd_partitions()' for more information
673 * @parser_data: MTD partition parser-specific data
674 * @parts: fallback partition information to register, if parsing fails;
675 * only valid if %nr_parts > %0
676 * @nr_parts: the number of partitions in parts, if zero then the full
677 * MTD device is registered if no partition info is found
679 * This function aggregates MTD partitions parsing (done by
680 * 'parse_mtd_partitions()') and MTD device and partitions registering. It
681 * basically follows the most common pattern found in many MTD drivers:
683 * * It first tries to probe partitions on MTD device @mtd using parsers
684 * specified in @types (if @types is %NULL, then the default list of parsers
685 * is used, see 'parse_mtd_partitions()' for more information). If none are
686 * found this functions tries to fallback to information specified in
688 * * If any partitioning info was found, this function registers the found
689 * partitions. If the MTD_PARTITIONED_MASTER option is set, then the device
690 * as a whole is registered first.
691 * * If no partitions were found this function just registers the MTD device
694 * Returns zero in case of success and a negative error code in case of failure.
696 int mtd_device_parse_register(struct mtd_info
*mtd
, const char * const *types
,
697 struct mtd_part_parser_data
*parser_data
,
698 const struct mtd_partition
*parts
,
701 struct mtd_partitions parsed
;
704 mtd_set_dev_defaults(mtd
);
706 memset(&parsed
, 0, sizeof(parsed
));
708 ret
= parse_mtd_partitions(mtd
, types
, &parsed
, parser_data
);
709 if ((ret
< 0 || parsed
.nr_parts
== 0) && parts
&& nr_parts
) {
710 /* Fall back to driver-provided partitions */
711 parsed
= (struct mtd_partitions
){
713 .nr_parts
= nr_parts
,
715 } else if (ret
< 0) {
716 /* Didn't come up with parsed OR fallback partitions */
717 pr_info("mtd: failed to find partitions; one or more parsers reports errors (%d)\n",
719 /* Don't abort on errors; we can still use unpartitioned MTD */
720 memset(&parsed
, 0, sizeof(parsed
));
723 ret
= mtd_add_device_partitions(mtd
, &parsed
);
728 * FIXME: some drivers unfortunately call this function more than once.
729 * So we have to check if we've already assigned the reboot notifier.
731 * Generally, we can make multiple calls work for most cases, but it
732 * does cause problems with parse_mtd_partitions() above (e.g.,
733 * cmdlineparts will register partitions more than once).
735 WARN_ONCE(mtd
->_reboot
&& mtd
->reboot_notifier
.notifier_call
,
736 "MTD already registered\n");
737 if (mtd
->_reboot
&& !mtd
->reboot_notifier
.notifier_call
) {
738 mtd
->reboot_notifier
.notifier_call
= mtd_reboot_notifier
;
739 register_reboot_notifier(&mtd
->reboot_notifier
);
743 /* Cleanup any parsed partitions */
744 mtd_part_parser_cleanup(&parsed
);
747 EXPORT_SYMBOL_GPL(mtd_device_parse_register
);
750 * mtd_device_unregister - unregister an existing MTD device.
752 * @master: the MTD device to unregister. This will unregister both the master
753 * and any partitions if registered.
755 int mtd_device_unregister(struct mtd_info
*master
)
760 unregister_reboot_notifier(&master
->reboot_notifier
);
762 err
= del_mtd_partitions(master
);
766 if (!device_is_registered(&master
->dev
))
769 return del_mtd_device(master
);
771 EXPORT_SYMBOL_GPL(mtd_device_unregister
);
774 * register_mtd_user - register a 'user' of MTD devices.
775 * @new: pointer to notifier info structure
777 * Registers a pair of callbacks function to be called upon addition
778 * or removal of MTD devices. Causes the 'add' callback to be immediately
779 * invoked for each MTD device currently present in the system.
781 void register_mtd_user (struct mtd_notifier
*new)
783 struct mtd_info
*mtd
;
785 mutex_lock(&mtd_table_mutex
);
787 list_add(&new->list
, &mtd_notifiers
);
789 __module_get(THIS_MODULE
);
791 mtd_for_each_device(mtd
)
794 mutex_unlock(&mtd_table_mutex
);
796 EXPORT_SYMBOL_GPL(register_mtd_user
);
799 * unregister_mtd_user - unregister a 'user' of MTD devices.
800 * @old: pointer to notifier info structure
802 * Removes a callback function pair from the list of 'users' to be
803 * notified upon addition or removal of MTD devices. Causes the
804 * 'remove' callback to be immediately invoked for each MTD device
805 * currently present in the system.
807 int unregister_mtd_user (struct mtd_notifier
*old
)
809 struct mtd_info
*mtd
;
811 mutex_lock(&mtd_table_mutex
);
813 module_put(THIS_MODULE
);
815 mtd_for_each_device(mtd
)
818 list_del(&old
->list
);
819 mutex_unlock(&mtd_table_mutex
);
822 EXPORT_SYMBOL_GPL(unregister_mtd_user
);
825 * get_mtd_device - obtain a validated handle for an MTD device
826 * @mtd: last known address of the required MTD device
827 * @num: internal device number of the required MTD device
829 * Given a number and NULL address, return the num'th entry in the device
830 * table, if any. Given an address and num == -1, search the device table
831 * for a device with that address and return if it's still present. Given
832 * both, return the num'th driver only if its address matches. Return
835 struct mtd_info
*get_mtd_device(struct mtd_info
*mtd
, int num
)
837 struct mtd_info
*ret
= NULL
, *other
;
840 mutex_lock(&mtd_table_mutex
);
843 mtd_for_each_device(other
) {
849 } else if (num
>= 0) {
850 ret
= idr_find(&mtd_idr
, num
);
851 if (mtd
&& mtd
!= ret
)
860 err
= __get_mtd_device(ret
);
864 mutex_unlock(&mtd_table_mutex
);
867 EXPORT_SYMBOL_GPL(get_mtd_device
);
870 int __get_mtd_device(struct mtd_info
*mtd
)
874 if (!try_module_get(mtd
->owner
))
877 if (mtd
->_get_device
) {
878 err
= mtd
->_get_device(mtd
);
881 module_put(mtd
->owner
);
888 EXPORT_SYMBOL_GPL(__get_mtd_device
);
891 * get_mtd_device_nm - obtain a validated handle for an MTD device by
893 * @name: MTD device name to open
895 * This function returns MTD device description structure in case of
896 * success and an error code in case of failure.
898 struct mtd_info
*get_mtd_device_nm(const char *name
)
901 struct mtd_info
*mtd
= NULL
, *other
;
903 mutex_lock(&mtd_table_mutex
);
905 mtd_for_each_device(other
) {
906 if (!strcmp(name
, other
->name
)) {
915 err
= __get_mtd_device(mtd
);
919 mutex_unlock(&mtd_table_mutex
);
923 mutex_unlock(&mtd_table_mutex
);
926 EXPORT_SYMBOL_GPL(get_mtd_device_nm
);
928 void put_mtd_device(struct mtd_info
*mtd
)
930 mutex_lock(&mtd_table_mutex
);
931 __put_mtd_device(mtd
);
932 mutex_unlock(&mtd_table_mutex
);
935 EXPORT_SYMBOL_GPL(put_mtd_device
);
937 void __put_mtd_device(struct mtd_info
*mtd
)
940 BUG_ON(mtd
->usecount
< 0);
942 if (mtd
->_put_device
)
943 mtd
->_put_device(mtd
);
945 module_put(mtd
->owner
);
947 EXPORT_SYMBOL_GPL(__put_mtd_device
);
950 * Erase is an asynchronous operation. Device drivers are supposed
951 * to call instr->callback() whenever the operation completes, even
952 * if it completes with a failure.
953 * Callers are supposed to pass a callback function and wait for it
954 * to be called before writing to the block.
956 int mtd_erase(struct mtd_info
*mtd
, struct erase_info
*instr
)
958 if (instr
->addr
>= mtd
->size
|| instr
->len
> mtd
->size
- instr
->addr
)
960 if (!(mtd
->flags
& MTD_WRITEABLE
))
962 instr
->fail_addr
= MTD_FAIL_ADDR_UNKNOWN
;
964 instr
->state
= MTD_ERASE_DONE
;
965 mtd_erase_callback(instr
);
968 ledtrig_mtd_activity();
969 return mtd
->_erase(mtd
, instr
);
971 EXPORT_SYMBOL_GPL(mtd_erase
);
974 * This stuff for eXecute-In-Place. phys is optional and may be set to NULL.
976 int mtd_point(struct mtd_info
*mtd
, loff_t from
, size_t len
, size_t *retlen
,
977 void **virt
, resource_size_t
*phys
)
985 if (from
< 0 || from
>= mtd
->size
|| len
> mtd
->size
- from
)
989 return mtd
->_point(mtd
, from
, len
, retlen
, virt
, phys
);
991 EXPORT_SYMBOL_GPL(mtd_point
);
993 /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
994 int mtd_unpoint(struct mtd_info
*mtd
, loff_t from
, size_t len
)
998 if (from
< 0 || from
>= mtd
->size
|| len
> mtd
->size
- from
)
1002 return mtd
->_unpoint(mtd
, from
, len
);
1004 EXPORT_SYMBOL_GPL(mtd_unpoint
);
1007 * Allow NOMMU mmap() to directly map the device (if not NULL)
1008 * - return the address to which the offset maps
1009 * - return -ENOSYS to indicate refusal to do the mapping
1011 unsigned long mtd_get_unmapped_area(struct mtd_info
*mtd
, unsigned long len
,
1012 unsigned long offset
, unsigned long flags
)
1014 if (!mtd
->_get_unmapped_area
)
1016 if (offset
>= mtd
->size
|| len
> mtd
->size
- offset
)
1018 return mtd
->_get_unmapped_area(mtd
, len
, offset
, flags
);
1020 EXPORT_SYMBOL_GPL(mtd_get_unmapped_area
);
1022 int mtd_read(struct mtd_info
*mtd
, loff_t from
, size_t len
, size_t *retlen
,
1027 if (from
< 0 || from
>= mtd
->size
|| len
> mtd
->size
- from
)
1032 ledtrig_mtd_activity();
1034 * In the absence of an error, drivers return a non-negative integer
1035 * representing the maximum number of bitflips that were corrected on
1036 * any one ecc region (if applicable; zero otherwise).
1038 ret_code
= mtd
->_read(mtd
, from
, len
, retlen
, buf
);
1039 if (unlikely(ret_code
< 0))
1041 if (mtd
->ecc_strength
== 0)
1042 return 0; /* device lacks ecc */
1043 return ret_code
>= mtd
->bitflip_threshold
? -EUCLEAN
: 0;
1045 EXPORT_SYMBOL_GPL(mtd_read
);
1047 int mtd_write(struct mtd_info
*mtd
, loff_t to
, size_t len
, size_t *retlen
,
1051 if (to
< 0 || to
>= mtd
->size
|| len
> mtd
->size
- to
)
1053 if (!mtd
->_write
|| !(mtd
->flags
& MTD_WRITEABLE
))
1057 ledtrig_mtd_activity();
1058 return mtd
->_write(mtd
, to
, len
, retlen
, buf
);
1060 EXPORT_SYMBOL_GPL(mtd_write
);
1063 * In blackbox flight recorder like scenarios we want to make successful writes
1064 * in interrupt context. panic_write() is only intended to be called when its
1065 * known the kernel is about to panic and we need the write to succeed. Since
1066 * the kernel is not going to be running for much longer, this function can
1067 * break locks and delay to ensure the write succeeds (but not sleep).
1069 int mtd_panic_write(struct mtd_info
*mtd
, loff_t to
, size_t len
, size_t *retlen
,
1073 if (!mtd
->_panic_write
)
1075 if (to
< 0 || to
>= mtd
->size
|| len
> mtd
->size
- to
)
1077 if (!(mtd
->flags
& MTD_WRITEABLE
))
1081 return mtd
->_panic_write(mtd
, to
, len
, retlen
, buf
);
1083 EXPORT_SYMBOL_GPL(mtd_panic_write
);
1085 int mtd_read_oob(struct mtd_info
*mtd
, loff_t from
, struct mtd_oob_ops
*ops
)
1088 ops
->retlen
= ops
->oobretlen
= 0;
1089 if (!mtd
->_read_oob
)
1092 ledtrig_mtd_activity();
1094 * In cases where ops->datbuf != NULL, mtd->_read_oob() has semantics
1095 * similar to mtd->_read(), returning a non-negative integer
1096 * representing max bitflips. In other cases, mtd->_read_oob() may
1097 * return -EUCLEAN. In all cases, perform similar logic to mtd_read().
1099 ret_code
= mtd
->_read_oob(mtd
, from
, ops
);
1100 if (unlikely(ret_code
< 0))
1102 if (mtd
->ecc_strength
== 0)
1103 return 0; /* device lacks ecc */
1104 return ret_code
>= mtd
->bitflip_threshold
? -EUCLEAN
: 0;
1106 EXPORT_SYMBOL_GPL(mtd_read_oob
);
1108 int mtd_write_oob(struct mtd_info
*mtd
, loff_t to
,
1109 struct mtd_oob_ops
*ops
)
1111 ops
->retlen
= ops
->oobretlen
= 0;
1112 if (!mtd
->_write_oob
)
1114 if (!(mtd
->flags
& MTD_WRITEABLE
))
1116 ledtrig_mtd_activity();
1117 return mtd
->_write_oob(mtd
, to
, ops
);
1119 EXPORT_SYMBOL_GPL(mtd_write_oob
);
1122 * mtd_ooblayout_ecc - Get the OOB region definition of a specific ECC section
1123 * @mtd: MTD device structure
1124 * @section: ECC section. Depending on the layout you may have all the ECC
1125 * bytes stored in a single contiguous section, or one section
1126 * per ECC chunk (and sometime several sections for a single ECC
1128 * @oobecc: OOB region struct filled with the appropriate ECC position
1131 * This function returns ECC section information in the OOB area. If you want
1132 * to get all the ECC bytes information, then you should call
1133 * mtd_ooblayout_ecc(mtd, section++, oobecc) until it returns -ERANGE.
1135 * Returns zero on success, a negative error code otherwise.
1137 int mtd_ooblayout_ecc(struct mtd_info
*mtd
, int section
,
1138 struct mtd_oob_region
*oobecc
)
1140 memset(oobecc
, 0, sizeof(*oobecc
));
1142 if (!mtd
|| section
< 0)
1145 if (!mtd
->ooblayout
|| !mtd
->ooblayout
->ecc
)
1148 return mtd
->ooblayout
->ecc(mtd
, section
, oobecc
);
1150 EXPORT_SYMBOL_GPL(mtd_ooblayout_ecc
);
1153 * mtd_ooblayout_free - Get the OOB region definition of a specific free
1155 * @mtd: MTD device structure
1156 * @section: Free section you are interested in. Depending on the layout
1157 * you may have all the free bytes stored in a single contiguous
1158 * section, or one section per ECC chunk plus an extra section
1159 * for the remaining bytes (or other funky layout).
1160 * @oobfree: OOB region struct filled with the appropriate free position
1163 * This function returns free bytes position in the OOB area. If you want
1164 * to get all the free bytes information, then you should call
1165 * mtd_ooblayout_free(mtd, section++, oobfree) until it returns -ERANGE.
1167 * Returns zero on success, a negative error code otherwise.
1169 int mtd_ooblayout_free(struct mtd_info
*mtd
, int section
,
1170 struct mtd_oob_region
*oobfree
)
1172 memset(oobfree
, 0, sizeof(*oobfree
));
1174 if (!mtd
|| section
< 0)
1177 if (!mtd
->ooblayout
|| !mtd
->ooblayout
->free
)
1180 return mtd
->ooblayout
->free(mtd
, section
, oobfree
);
1182 EXPORT_SYMBOL_GPL(mtd_ooblayout_free
);
1185 * mtd_ooblayout_find_region - Find the region attached to a specific byte
1186 * @mtd: mtd info structure
1187 * @byte: the byte we are searching for
1188 * @sectionp: pointer where the section id will be stored
1189 * @oobregion: used to retrieve the ECC position
1190 * @iter: iterator function. Should be either mtd_ooblayout_free or
1191 * mtd_ooblayout_ecc depending on the region type you're searching for
1193 * This function returns the section id and oobregion information of a
1194 * specific byte. For example, say you want to know where the 4th ECC byte is
1195 * stored, you'll use:
1197 * mtd_ooblayout_find_region(mtd, 3, §ion, &oobregion, mtd_ooblayout_ecc);
1199 * Returns zero on success, a negative error code otherwise.
1201 static int mtd_ooblayout_find_region(struct mtd_info
*mtd
, int byte
,
1202 int *sectionp
, struct mtd_oob_region
*oobregion
,
1203 int (*iter
)(struct mtd_info
*,
1205 struct mtd_oob_region
*oobregion
))
1207 int pos
= 0, ret
, section
= 0;
1209 memset(oobregion
, 0, sizeof(*oobregion
));
1212 ret
= iter(mtd
, section
, oobregion
);
1216 if (pos
+ oobregion
->length
> byte
)
1219 pos
+= oobregion
->length
;
1224 * Adjust region info to make it start at the beginning at the
1227 oobregion
->offset
+= byte
- pos
;
1228 oobregion
->length
-= byte
- pos
;
1229 *sectionp
= section
;
1235 * mtd_ooblayout_find_eccregion - Find the ECC region attached to a specific
1237 * @mtd: mtd info structure
1238 * @eccbyte: the byte we are searching for
1239 * @sectionp: pointer where the section id will be stored
1240 * @oobregion: OOB region information
1242 * Works like mtd_ooblayout_find_region() except it searches for a specific ECC
1245 * Returns zero on success, a negative error code otherwise.
1247 int mtd_ooblayout_find_eccregion(struct mtd_info
*mtd
, int eccbyte
,
1249 struct mtd_oob_region
*oobregion
)
1251 return mtd_ooblayout_find_region(mtd
, eccbyte
, section
, oobregion
,
1254 EXPORT_SYMBOL_GPL(mtd_ooblayout_find_eccregion
);
1257 * mtd_ooblayout_get_bytes - Extract OOB bytes from the oob buffer
1258 * @mtd: mtd info structure
1259 * @buf: destination buffer to store OOB bytes
1260 * @oobbuf: OOB buffer
1261 * @start: first byte to retrieve
1262 * @nbytes: number of bytes to retrieve
1263 * @iter: section iterator
1265 * Extract bytes attached to a specific category (ECC or free)
1266 * from the OOB buffer and copy them into buf.
1268 * Returns zero on success, a negative error code otherwise.
1270 static int mtd_ooblayout_get_bytes(struct mtd_info
*mtd
, u8
*buf
,
1271 const u8
*oobbuf
, int start
, int nbytes
,
1272 int (*iter
)(struct mtd_info
*,
1274 struct mtd_oob_region
*oobregion
))
1276 struct mtd_oob_region oobregion
;
1279 ret
= mtd_ooblayout_find_region(mtd
, start
, §ion
,
1285 cnt
= min_t(int, nbytes
, oobregion
.length
);
1286 memcpy(buf
, oobbuf
+ oobregion
.offset
, cnt
);
1293 ret
= iter(mtd
, ++section
, &oobregion
);
1300 * mtd_ooblayout_set_bytes - put OOB bytes into the oob buffer
1301 * @mtd: mtd info structure
1302 * @buf: source buffer to get OOB bytes from
1303 * @oobbuf: OOB buffer
1304 * @start: first OOB byte to set
1305 * @nbytes: number of OOB bytes to set
1306 * @iter: section iterator
1308 * Fill the OOB buffer with data provided in buf. The category (ECC or free)
1309 * is selected by passing the appropriate iterator.
1311 * Returns zero on success, a negative error code otherwise.
1313 static int mtd_ooblayout_set_bytes(struct mtd_info
*mtd
, const u8
*buf
,
1314 u8
*oobbuf
, int start
, int nbytes
,
1315 int (*iter
)(struct mtd_info
*,
1317 struct mtd_oob_region
*oobregion
))
1319 struct mtd_oob_region oobregion
;
1322 ret
= mtd_ooblayout_find_region(mtd
, start
, §ion
,
1328 cnt
= min_t(int, nbytes
, oobregion
.length
);
1329 memcpy(oobbuf
+ oobregion
.offset
, buf
, cnt
);
1336 ret
= iter(mtd
, ++section
, &oobregion
);
1343 * mtd_ooblayout_count_bytes - count the number of bytes in a OOB category
1344 * @mtd: mtd info structure
1345 * @iter: category iterator
1347 * Count the number of bytes in a given category.
1349 * Returns a positive value on success, a negative error code otherwise.
1351 static int mtd_ooblayout_count_bytes(struct mtd_info
*mtd
,
1352 int (*iter
)(struct mtd_info
*,
1354 struct mtd_oob_region
*oobregion
))
1356 struct mtd_oob_region oobregion
;
1357 int section
= 0, ret
, nbytes
= 0;
1360 ret
= iter(mtd
, section
++, &oobregion
);
1367 nbytes
+= oobregion
.length
;
1374 * mtd_ooblayout_get_eccbytes - extract ECC bytes from the oob buffer
1375 * @mtd: mtd info structure
1376 * @eccbuf: destination buffer to store ECC bytes
1377 * @oobbuf: OOB buffer
1378 * @start: first ECC byte to retrieve
1379 * @nbytes: number of ECC bytes to retrieve
1381 * Works like mtd_ooblayout_get_bytes(), except it acts on ECC bytes.
1383 * Returns zero on success, a negative error code otherwise.
1385 int mtd_ooblayout_get_eccbytes(struct mtd_info
*mtd
, u8
*eccbuf
,
1386 const u8
*oobbuf
, int start
, int nbytes
)
1388 return mtd_ooblayout_get_bytes(mtd
, eccbuf
, oobbuf
, start
, nbytes
,
1391 EXPORT_SYMBOL_GPL(mtd_ooblayout_get_eccbytes
);
1394 * mtd_ooblayout_set_eccbytes - set ECC bytes into the oob buffer
1395 * @mtd: mtd info structure
1396 * @eccbuf: source buffer to get ECC bytes from
1397 * @oobbuf: OOB buffer
1398 * @start: first ECC byte to set
1399 * @nbytes: number of ECC bytes to set
1401 * Works like mtd_ooblayout_set_bytes(), except it acts on ECC bytes.
1403 * Returns zero on success, a negative error code otherwise.
1405 int mtd_ooblayout_set_eccbytes(struct mtd_info
*mtd
, const u8
*eccbuf
,
1406 u8
*oobbuf
, int start
, int nbytes
)
1408 return mtd_ooblayout_set_bytes(mtd
, eccbuf
, oobbuf
, start
, nbytes
,
1411 EXPORT_SYMBOL_GPL(mtd_ooblayout_set_eccbytes
);
1414 * mtd_ooblayout_get_databytes - extract data bytes from the oob buffer
1415 * @mtd: mtd info structure
1416 * @databuf: destination buffer to store ECC bytes
1417 * @oobbuf: OOB buffer
1418 * @start: first ECC byte to retrieve
1419 * @nbytes: number of ECC bytes to retrieve
1421 * Works like mtd_ooblayout_get_bytes(), except it acts on free bytes.
1423 * Returns zero on success, a negative error code otherwise.
1425 int mtd_ooblayout_get_databytes(struct mtd_info
*mtd
, u8
*databuf
,
1426 const u8
*oobbuf
, int start
, int nbytes
)
1428 return mtd_ooblayout_get_bytes(mtd
, databuf
, oobbuf
, start
, nbytes
,
1429 mtd_ooblayout_free
);
1431 EXPORT_SYMBOL_GPL(mtd_ooblayout_get_databytes
);
1434 * mtd_ooblayout_get_eccbytes - set data bytes into the oob buffer
1435 * @mtd: mtd info structure
1436 * @eccbuf: source buffer to get data bytes from
1437 * @oobbuf: OOB buffer
1438 * @start: first ECC byte to set
1439 * @nbytes: number of ECC bytes to set
1441 * Works like mtd_ooblayout_get_bytes(), except it acts on free bytes.
1443 * Returns zero on success, a negative error code otherwise.
1445 int mtd_ooblayout_set_databytes(struct mtd_info
*mtd
, const u8
*databuf
,
1446 u8
*oobbuf
, int start
, int nbytes
)
1448 return mtd_ooblayout_set_bytes(mtd
, databuf
, oobbuf
, start
, nbytes
,
1449 mtd_ooblayout_free
);
1451 EXPORT_SYMBOL_GPL(mtd_ooblayout_set_databytes
);
1454 * mtd_ooblayout_count_freebytes - count the number of free bytes in OOB
1455 * @mtd: mtd info structure
1457 * Works like mtd_ooblayout_count_bytes(), except it count free bytes.
1459 * Returns zero on success, a negative error code otherwise.
1461 int mtd_ooblayout_count_freebytes(struct mtd_info
*mtd
)
1463 return mtd_ooblayout_count_bytes(mtd
, mtd_ooblayout_free
);
1465 EXPORT_SYMBOL_GPL(mtd_ooblayout_count_freebytes
);
1468 * mtd_ooblayout_count_freebytes - count the number of ECC bytes in OOB
1469 * @mtd: mtd info structure
1471 * Works like mtd_ooblayout_count_bytes(), except it count ECC bytes.
1473 * Returns zero on success, a negative error code otherwise.
1475 int mtd_ooblayout_count_eccbytes(struct mtd_info
*mtd
)
1477 return mtd_ooblayout_count_bytes(mtd
, mtd_ooblayout_ecc
);
1479 EXPORT_SYMBOL_GPL(mtd_ooblayout_count_eccbytes
);
1482 * Method to access the protection register area, present in some flash
1483 * devices. The user data is one time programmable but the factory data is read
1486 int mtd_get_fact_prot_info(struct mtd_info
*mtd
, size_t len
, size_t *retlen
,
1487 struct otp_info
*buf
)
1489 if (!mtd
->_get_fact_prot_info
)
1493 return mtd
->_get_fact_prot_info(mtd
, len
, retlen
, buf
);
1495 EXPORT_SYMBOL_GPL(mtd_get_fact_prot_info
);
1497 int mtd_read_fact_prot_reg(struct mtd_info
*mtd
, loff_t from
, size_t len
,
1498 size_t *retlen
, u_char
*buf
)
1501 if (!mtd
->_read_fact_prot_reg
)
1505 return mtd
->_read_fact_prot_reg(mtd
, from
, len
, retlen
, buf
);
1507 EXPORT_SYMBOL_GPL(mtd_read_fact_prot_reg
);
1509 int mtd_get_user_prot_info(struct mtd_info
*mtd
, size_t len
, size_t *retlen
,
1510 struct otp_info
*buf
)
1512 if (!mtd
->_get_user_prot_info
)
1516 return mtd
->_get_user_prot_info(mtd
, len
, retlen
, buf
);
1518 EXPORT_SYMBOL_GPL(mtd_get_user_prot_info
);
1520 int mtd_read_user_prot_reg(struct mtd_info
*mtd
, loff_t from
, size_t len
,
1521 size_t *retlen
, u_char
*buf
)
1524 if (!mtd
->_read_user_prot_reg
)
1528 return mtd
->_read_user_prot_reg(mtd
, from
, len
, retlen
, buf
);
1530 EXPORT_SYMBOL_GPL(mtd_read_user_prot_reg
);
1532 int mtd_write_user_prot_reg(struct mtd_info
*mtd
, loff_t to
, size_t len
,
1533 size_t *retlen
, u_char
*buf
)
1538 if (!mtd
->_write_user_prot_reg
)
1542 ret
= mtd
->_write_user_prot_reg(mtd
, to
, len
, retlen
, buf
);
1547 * If no data could be written at all, we are out of memory and
1548 * must return -ENOSPC.
1550 return (*retlen
) ? 0 : -ENOSPC
;
1552 EXPORT_SYMBOL_GPL(mtd_write_user_prot_reg
);
1554 int mtd_lock_user_prot_reg(struct mtd_info
*mtd
, loff_t from
, size_t len
)
1556 if (!mtd
->_lock_user_prot_reg
)
1560 return mtd
->_lock_user_prot_reg(mtd
, from
, len
);
1562 EXPORT_SYMBOL_GPL(mtd_lock_user_prot_reg
);
1564 /* Chip-supported device locking */
1565 int mtd_lock(struct mtd_info
*mtd
, loff_t ofs
, uint64_t len
)
1569 if (ofs
< 0 || ofs
>= mtd
->size
|| len
> mtd
->size
- ofs
)
1573 return mtd
->_lock(mtd
, ofs
, len
);
1575 EXPORT_SYMBOL_GPL(mtd_lock
);
1577 int mtd_unlock(struct mtd_info
*mtd
, loff_t ofs
, uint64_t len
)
1581 if (ofs
< 0 || ofs
>= mtd
->size
|| len
> mtd
->size
- ofs
)
1585 return mtd
->_unlock(mtd
, ofs
, len
);
1587 EXPORT_SYMBOL_GPL(mtd_unlock
);
1589 int mtd_is_locked(struct mtd_info
*mtd
, loff_t ofs
, uint64_t len
)
1591 if (!mtd
->_is_locked
)
1593 if (ofs
< 0 || ofs
>= mtd
->size
|| len
> mtd
->size
- ofs
)
1597 return mtd
->_is_locked(mtd
, ofs
, len
);
1599 EXPORT_SYMBOL_GPL(mtd_is_locked
);
1601 int mtd_block_isreserved(struct mtd_info
*mtd
, loff_t ofs
)
1603 if (ofs
< 0 || ofs
>= mtd
->size
)
1605 if (!mtd
->_block_isreserved
)
1607 return mtd
->_block_isreserved(mtd
, ofs
);
1609 EXPORT_SYMBOL_GPL(mtd_block_isreserved
);
1611 int mtd_block_isbad(struct mtd_info
*mtd
, loff_t ofs
)
1613 if (ofs
< 0 || ofs
>= mtd
->size
)
1615 if (!mtd
->_block_isbad
)
1617 return mtd
->_block_isbad(mtd
, ofs
);
1619 EXPORT_SYMBOL_GPL(mtd_block_isbad
);
1621 int mtd_block_markbad(struct mtd_info
*mtd
, loff_t ofs
)
1623 if (!mtd
->_block_markbad
)
1625 if (ofs
< 0 || ofs
>= mtd
->size
)
1627 if (!(mtd
->flags
& MTD_WRITEABLE
))
1629 return mtd
->_block_markbad(mtd
, ofs
);
1631 EXPORT_SYMBOL_GPL(mtd_block_markbad
);
1634 * default_mtd_writev - the default writev method
1635 * @mtd: mtd device description object pointer
1636 * @vecs: the vectors to write
1637 * @count: count of vectors in @vecs
1638 * @to: the MTD device offset to write to
1639 * @retlen: on exit contains the count of bytes written to the MTD device.
1641 * This function returns zero in case of success and a negative error code in
1644 static int default_mtd_writev(struct mtd_info
*mtd
, const struct kvec
*vecs
,
1645 unsigned long count
, loff_t to
, size_t *retlen
)
1648 size_t totlen
= 0, thislen
;
1651 for (i
= 0; i
< count
; i
++) {
1652 if (!vecs
[i
].iov_len
)
1654 ret
= mtd_write(mtd
, to
, vecs
[i
].iov_len
, &thislen
,
1657 if (ret
|| thislen
!= vecs
[i
].iov_len
)
1659 to
+= vecs
[i
].iov_len
;
1666 * mtd_writev - the vector-based MTD write method
1667 * @mtd: mtd device description object pointer
1668 * @vecs: the vectors to write
1669 * @count: count of vectors in @vecs
1670 * @to: the MTD device offset to write to
1671 * @retlen: on exit contains the count of bytes written to the MTD device.
1673 * This function returns zero in case of success and a negative error code in
1676 int mtd_writev(struct mtd_info
*mtd
, const struct kvec
*vecs
,
1677 unsigned long count
, loff_t to
, size_t *retlen
)
1680 if (!(mtd
->flags
& MTD_WRITEABLE
))
1683 return default_mtd_writev(mtd
, vecs
, count
, to
, retlen
);
1684 return mtd
->_writev(mtd
, vecs
, count
, to
, retlen
);
1686 EXPORT_SYMBOL_GPL(mtd_writev
);
1689 * mtd_kmalloc_up_to - allocate a contiguous buffer up to the specified size
1690 * @mtd: mtd device description object pointer
1691 * @size: a pointer to the ideal or maximum size of the allocation, points
1692 * to the actual allocation size on success.
1694 * This routine attempts to allocate a contiguous kernel buffer up to
1695 * the specified size, backing off the size of the request exponentially
1696 * until the request succeeds or until the allocation size falls below
1697 * the system page size. This attempts to make sure it does not adversely
1698 * impact system performance, so when allocating more than one page, we
1699 * ask the memory allocator to avoid re-trying, swapping, writing back
1700 * or performing I/O.
1702 * Note, this function also makes sure that the allocated buffer is aligned to
1703 * the MTD device's min. I/O unit, i.e. the "mtd->writesize" value.
1705 * This is called, for example by mtd_{read,write} and jffs2_scan_medium,
1706 * to handle smaller (i.e. degraded) buffer allocations under low- or
1707 * fragmented-memory situations where such reduced allocations, from a
1708 * requested ideal, are allowed.
1710 * Returns a pointer to the allocated buffer on success; otherwise, NULL.
1712 void *mtd_kmalloc_up_to(const struct mtd_info
*mtd
, size_t *size
)
1714 gfp_t flags
= __GFP_NOWARN
| __GFP_DIRECT_RECLAIM
| __GFP_NORETRY
;
1715 size_t min_alloc
= max_t(size_t, mtd
->writesize
, PAGE_SIZE
);
1718 *size
= min_t(size_t, *size
, KMALLOC_MAX_SIZE
);
1720 while (*size
> min_alloc
) {
1721 kbuf
= kmalloc(*size
, flags
);
1726 *size
= ALIGN(*size
, mtd
->writesize
);
1730 * For the last resort allocation allow 'kmalloc()' to do all sorts of
1731 * things (write-back, dropping caches, etc) by using GFP_KERNEL.
1733 return kmalloc(*size
, GFP_KERNEL
);
1735 EXPORT_SYMBOL_GPL(mtd_kmalloc_up_to
);
1737 #ifdef CONFIG_PROC_FS
1739 /*====================================================================*/
1740 /* Support for /proc/mtd */
1742 static int mtd_proc_show(struct seq_file
*m
, void *v
)
1744 struct mtd_info
*mtd
;
1746 seq_puts(m
, "dev: size erasesize name\n");
1747 mutex_lock(&mtd_table_mutex
);
1748 mtd_for_each_device(mtd
) {
1749 seq_printf(m
, "mtd%d: %8.8llx %8.8x \"%s\"\n",
1750 mtd
->index
, (unsigned long long)mtd
->size
,
1751 mtd
->erasesize
, mtd
->name
);
1753 mutex_unlock(&mtd_table_mutex
);
1757 static int mtd_proc_open(struct inode
*inode
, struct file
*file
)
1759 return single_open(file
, mtd_proc_show
, NULL
);
1762 static const struct file_operations mtd_proc_ops
= {
1763 .open
= mtd_proc_open
,
1765 .llseek
= seq_lseek
,
1766 .release
= single_release
,
1768 #endif /* CONFIG_PROC_FS */
1770 /*====================================================================*/
1773 static struct backing_dev_info
* __init
mtd_bdi_init(char *name
)
1775 struct backing_dev_info
*bdi
;
1778 bdi
= kzalloc(sizeof(*bdi
), GFP_KERNEL
);
1780 return ERR_PTR(-ENOMEM
);
1782 ret
= bdi_setup_and_register(bdi
, name
);
1786 return ret
? ERR_PTR(ret
) : bdi
;
1789 static struct proc_dir_entry
*proc_mtd
;
1791 static int __init
init_mtd(void)
1795 ret
= class_register(&mtd_class
);
1799 mtd_bdi
= mtd_bdi_init("mtd");
1800 if (IS_ERR(mtd_bdi
)) {
1801 ret
= PTR_ERR(mtd_bdi
);
1805 proc_mtd
= proc_create("mtd", 0, NULL
, &mtd_proc_ops
);
1807 ret
= init_mtdchar();
1815 remove_proc_entry("mtd", NULL
);
1816 bdi_destroy(mtd_bdi
);
1819 class_unregister(&mtd_class
);
1821 pr_err("Error registering mtd class or bdi: %d\n", ret
);
1825 static void __exit
cleanup_mtd(void)
1829 remove_proc_entry("mtd", NULL
);
1830 class_unregister(&mtd_class
);
1831 bdi_destroy(mtd_bdi
);
1833 idr_destroy(&mtd_idr
);
1836 module_init(init_mtd
);
1837 module_exit(cleanup_mtd
);
1839 MODULE_LICENSE("GPL");
1840 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
1841 MODULE_DESCRIPTION("Core MTD registration and access routines");