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>
43 #include <linux/leds.h>
45 #include <linux/mtd/mtd.h>
46 #include <linux/mtd/partitions.h>
50 static struct backing_dev_info mtd_bdi = {
53 #ifdef CONFIG_PM_SLEEP
55 static int mtd_cls_suspend(struct device *dev)
57 struct mtd_info *mtd = dev_get_drvdata(dev);
59 return mtd ? mtd_suspend(mtd) : 0;
62 static int mtd_cls_resume(struct device *dev)
64 struct mtd_info *mtd = dev_get_drvdata(dev);
71 static SIMPLE_DEV_PM_OPS(mtd_cls_pm_ops, mtd_cls_suspend, mtd_cls_resume);
72 #define MTD_CLS_PM_OPS (&mtd_cls_pm_ops)
74 #define MTD_CLS_PM_OPS NULL
77 static struct class mtd_class = {
83 static DEFINE_IDR(mtd_idr);
85 /* These are exported solely for the purpose of mtd_blkdevs.c. You
86 should not use them for _anything_ else */
87 DEFINE_MUTEX(mtd_table_mutex);
88 EXPORT_SYMBOL_GPL(mtd_table_mutex);
90 struct mtd_info *__mtd_next_device(int i)
92 return idr_get_next(&mtd_idr, &i);
94 EXPORT_SYMBOL_GPL(__mtd_next_device);
96 static LIST_HEAD(mtd_notifiers);
99 #define MTD_DEVT(index) MKDEV(MTD_CHAR_MAJOR, (index)*2)
101 /* REVISIT once MTD uses the driver model better, whoever allocates
102 * the mtd_info will probably want to use the release() hook...
104 static void mtd_release(struct device *dev)
106 struct mtd_info *mtd = dev_get_drvdata(dev);
107 dev_t index = MTD_DEVT(mtd->index);
109 /* remove /dev/mtdXro node */
110 device_destroy(&mtd_class, index + 1);
113 static ssize_t mtd_type_show(struct device *dev,
114 struct device_attribute *attr, char *buf)
116 struct mtd_info *mtd = dev_get_drvdata(dev);
141 case MTD_MLCNANDFLASH:
148 return snprintf(buf, PAGE_SIZE, "%s\n", type);
150 static DEVICE_ATTR(type, S_IRUGO, mtd_type_show, NULL);
152 static ssize_t mtd_flags_show(struct device *dev,
153 struct device_attribute *attr, char *buf)
155 struct mtd_info *mtd = dev_get_drvdata(dev);
157 return snprintf(buf, PAGE_SIZE, "0x%lx\n", (unsigned long)mtd->flags);
160 static DEVICE_ATTR(flags, S_IRUGO, mtd_flags_show, NULL);
162 static ssize_t mtd_size_show(struct device *dev,
163 struct device_attribute *attr, char *buf)
165 struct mtd_info *mtd = dev_get_drvdata(dev);
167 return snprintf(buf, PAGE_SIZE, "%llu\n",
168 (unsigned long long)mtd->size);
171 static DEVICE_ATTR(size, S_IRUGO, mtd_size_show, NULL);
173 static ssize_t mtd_erasesize_show(struct device *dev,
174 struct device_attribute *attr, char *buf)
176 struct mtd_info *mtd = dev_get_drvdata(dev);
178 return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->erasesize);
181 static DEVICE_ATTR(erasesize, S_IRUGO, mtd_erasesize_show, NULL);
183 static ssize_t mtd_writesize_show(struct device *dev,
184 struct device_attribute *attr, char *buf)
186 struct mtd_info *mtd = dev_get_drvdata(dev);
188 return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->writesize);
191 static DEVICE_ATTR(writesize, S_IRUGO, mtd_writesize_show, NULL);
193 static ssize_t mtd_subpagesize_show(struct device *dev,
194 struct device_attribute *attr, char *buf)
196 struct mtd_info *mtd = dev_get_drvdata(dev);
197 unsigned int subpagesize = mtd->writesize >> mtd->subpage_sft;
199 return snprintf(buf, PAGE_SIZE, "%u\n", subpagesize);
202 static DEVICE_ATTR(subpagesize, S_IRUGO, mtd_subpagesize_show, NULL);
204 static ssize_t mtd_oobsize_show(struct device *dev,
205 struct device_attribute *attr, char *buf)
207 struct mtd_info *mtd = dev_get_drvdata(dev);
209 return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->oobsize);
212 static DEVICE_ATTR(oobsize, S_IRUGO, mtd_oobsize_show, NULL);
214 static ssize_t mtd_numeraseregions_show(struct device *dev,
215 struct device_attribute *attr, char *buf)
217 struct mtd_info *mtd = dev_get_drvdata(dev);
219 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->numeraseregions);
222 static DEVICE_ATTR(numeraseregions, S_IRUGO, mtd_numeraseregions_show,
225 static ssize_t mtd_name_show(struct device *dev,
226 struct device_attribute *attr, char *buf)
228 struct mtd_info *mtd = dev_get_drvdata(dev);
230 return snprintf(buf, PAGE_SIZE, "%s\n", mtd->name);
233 static DEVICE_ATTR(name, S_IRUGO, mtd_name_show, NULL);
235 static ssize_t mtd_ecc_strength_show(struct device *dev,
236 struct device_attribute *attr, char *buf)
238 struct mtd_info *mtd = dev_get_drvdata(dev);
240 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->ecc_strength);
242 static DEVICE_ATTR(ecc_strength, S_IRUGO, mtd_ecc_strength_show, NULL);
244 static ssize_t mtd_bitflip_threshold_show(struct device *dev,
245 struct device_attribute *attr,
248 struct mtd_info *mtd = dev_get_drvdata(dev);
250 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->bitflip_threshold);
253 static ssize_t mtd_bitflip_threshold_store(struct device *dev,
254 struct device_attribute *attr,
255 const char *buf, size_t count)
257 struct mtd_info *mtd = dev_get_drvdata(dev);
258 unsigned int bitflip_threshold;
261 retval = kstrtouint(buf, 0, &bitflip_threshold);
265 mtd->bitflip_threshold = bitflip_threshold;
268 static DEVICE_ATTR(bitflip_threshold, S_IRUGO | S_IWUSR,
269 mtd_bitflip_threshold_show,
270 mtd_bitflip_threshold_store);
272 static ssize_t mtd_ecc_step_size_show(struct device *dev,
273 struct device_attribute *attr, char *buf)
275 struct mtd_info *mtd = dev_get_drvdata(dev);
277 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->ecc_step_size);
280 static DEVICE_ATTR(ecc_step_size, S_IRUGO, mtd_ecc_step_size_show, NULL);
282 static ssize_t mtd_ecc_stats_corrected_show(struct device *dev,
283 struct device_attribute *attr, char *buf)
285 struct mtd_info *mtd = dev_get_drvdata(dev);
286 struct mtd_ecc_stats *ecc_stats = &mtd->ecc_stats;
288 return snprintf(buf, PAGE_SIZE, "%u\n", ecc_stats->corrected);
290 static DEVICE_ATTR(corrected_bits, S_IRUGO,
291 mtd_ecc_stats_corrected_show, NULL);
293 static ssize_t mtd_ecc_stats_errors_show(struct device *dev,
294 struct device_attribute *attr, char *buf)
296 struct mtd_info *mtd = dev_get_drvdata(dev);
297 struct mtd_ecc_stats *ecc_stats = &mtd->ecc_stats;
299 return snprintf(buf, PAGE_SIZE, "%u\n", ecc_stats->failed);
301 static DEVICE_ATTR(ecc_failures, S_IRUGO, mtd_ecc_stats_errors_show, NULL);
303 static ssize_t mtd_badblocks_show(struct device *dev,
304 struct device_attribute *attr, char *buf)
306 struct mtd_info *mtd = dev_get_drvdata(dev);
307 struct mtd_ecc_stats *ecc_stats = &mtd->ecc_stats;
309 return snprintf(buf, PAGE_SIZE, "%u\n", ecc_stats->badblocks);
311 static DEVICE_ATTR(bad_blocks, S_IRUGO, mtd_badblocks_show, NULL);
313 static ssize_t mtd_bbtblocks_show(struct device *dev,
314 struct device_attribute *attr, char *buf)
316 struct mtd_info *mtd = dev_get_drvdata(dev);
317 struct mtd_ecc_stats *ecc_stats = &mtd->ecc_stats;
319 return snprintf(buf, PAGE_SIZE, "%u\n", ecc_stats->bbtblocks);
321 static DEVICE_ATTR(bbt_blocks, S_IRUGO, mtd_bbtblocks_show, NULL);
323 static struct attribute *mtd_attrs[] = {
325 &dev_attr_flags.attr,
327 &dev_attr_erasesize.attr,
328 &dev_attr_writesize.attr,
329 &dev_attr_subpagesize.attr,
330 &dev_attr_oobsize.attr,
331 &dev_attr_numeraseregions.attr,
333 &dev_attr_ecc_strength.attr,
334 &dev_attr_ecc_step_size.attr,
335 &dev_attr_corrected_bits.attr,
336 &dev_attr_ecc_failures.attr,
337 &dev_attr_bad_blocks.attr,
338 &dev_attr_bbt_blocks.attr,
339 &dev_attr_bitflip_threshold.attr,
342 ATTRIBUTE_GROUPS(mtd);
344 static struct device_type mtd_devtype = {
346 .groups = mtd_groups,
347 .release = mtd_release,
351 unsigned mtd_mmap_capabilities(struct mtd_info *mtd)
355 return NOMMU_MAP_COPY | NOMMU_MAP_DIRECT | NOMMU_MAP_EXEC |
356 NOMMU_MAP_READ | NOMMU_MAP_WRITE;
358 return NOMMU_MAP_COPY | NOMMU_MAP_DIRECT | NOMMU_MAP_EXEC |
361 return NOMMU_MAP_COPY;
364 EXPORT_SYMBOL_GPL(mtd_mmap_capabilities);
367 static int mtd_reboot_notifier(struct notifier_block *n, unsigned long state,
370 struct mtd_info *mtd;
372 mtd = container_of(n, struct mtd_info, reboot_notifier);
379 * add_mtd_device - register an MTD device
380 * @mtd: pointer to new MTD device info structure
382 * Add a device to the list of MTD devices present in the system, and
383 * notify each currently active MTD 'user' of its arrival. Returns
384 * zero on success or non-zero on failure.
387 int add_mtd_device(struct mtd_info *mtd)
389 struct mtd_notifier *not;
393 * May occur, for instance, on buggy drivers which call
394 * mtd_device_parse_register() multiple times on the same master MTD,
395 * especially with CONFIG_MTD_PARTITIONED_MASTER=y.
397 if (WARN_ONCE(mtd->backing_dev_info, "MTD already registered\n"))
400 mtd->backing_dev_info = &mtd_bdi;
402 BUG_ON(mtd->writesize == 0);
403 mutex_lock(&mtd_table_mutex);
405 i = idr_alloc(&mtd_idr, mtd, 0, 0, GFP_KERNEL);
414 /* default value if not set by driver */
415 if (mtd->bitflip_threshold == 0)
416 mtd->bitflip_threshold = mtd->ecc_strength;
418 if (is_power_of_2(mtd->erasesize))
419 mtd->erasesize_shift = ffs(mtd->erasesize) - 1;
421 mtd->erasesize_shift = 0;
423 if (is_power_of_2(mtd->writesize))
424 mtd->writesize_shift = ffs(mtd->writesize) - 1;
426 mtd->writesize_shift = 0;
428 mtd->erasesize_mask = (1 << mtd->erasesize_shift) - 1;
429 mtd->writesize_mask = (1 << mtd->writesize_shift) - 1;
431 /* Some chips always power up locked. Unlock them now */
432 if ((mtd->flags & MTD_WRITEABLE) && (mtd->flags & MTD_POWERUP_LOCK)) {
433 error = mtd_unlock(mtd, 0, mtd->size);
434 if (error && error != -EOPNOTSUPP)
436 "%s: unlock failed, writes may not work\n",
438 /* Ignore unlock failures? */
442 /* Caller should have set dev.parent to match the
443 * physical device, if appropriate.
445 mtd->dev.type = &mtd_devtype;
446 mtd->dev.class = &mtd_class;
447 mtd->dev.devt = MTD_DEVT(i);
448 dev_set_name(&mtd->dev, "mtd%d", i);
449 dev_set_drvdata(&mtd->dev, mtd);
450 of_node_get(mtd_get_of_node(mtd));
451 error = device_register(&mtd->dev);
455 device_create(&mtd_class, mtd->dev.parent, MTD_DEVT(i) + 1, NULL,
458 pr_debug("mtd: Giving out device %d to %s\n", i, mtd->name);
459 /* No need to get a refcount on the module containing
460 the notifier, since we hold the mtd_table_mutex */
461 list_for_each_entry(not, &mtd_notifiers, list)
464 mutex_unlock(&mtd_table_mutex);
465 /* We _know_ we aren't being removed, because
466 our caller is still holding us here. So none
467 of this try_ nonsense, and no bitching about it
469 __module_get(THIS_MODULE);
473 of_node_put(mtd_get_of_node(mtd));
474 idr_remove(&mtd_idr, i);
476 mutex_unlock(&mtd_table_mutex);
481 * del_mtd_device - unregister an MTD device
482 * @mtd: pointer to MTD device info structure
484 * Remove a device from the list of MTD devices present in the system,
485 * and notify each currently active MTD 'user' of its departure.
486 * Returns zero on success or 1 on failure, which currently will happen
487 * if the requested device does not appear to be present in the list.
490 int del_mtd_device(struct mtd_info *mtd)
493 struct mtd_notifier *not;
495 mutex_lock(&mtd_table_mutex);
497 if (idr_find(&mtd_idr, mtd->index) != mtd) {
502 /* No need to get a refcount on the module containing
503 the notifier, since we hold the mtd_table_mutex */
504 list_for_each_entry(not, &mtd_notifiers, list)
508 printk(KERN_NOTICE "Removing MTD device #%d (%s) with use count %d\n",
509 mtd->index, mtd->name, mtd->usecount);
512 device_unregister(&mtd->dev);
514 idr_remove(&mtd_idr, mtd->index);
515 of_node_put(mtd_get_of_node(mtd));
517 module_put(THIS_MODULE);
522 mutex_unlock(&mtd_table_mutex);
526 static int mtd_add_device_partitions(struct mtd_info *mtd,
527 struct mtd_partitions *parts)
529 const struct mtd_partition *real_parts = parts->parts;
530 int nbparts = parts->nr_parts;
533 if (nbparts == 0 || IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER)) {
534 ret = add_mtd_device(mtd);
540 ret = add_mtd_partitions(mtd, real_parts, nbparts);
541 if (ret && IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER))
550 * Set a few defaults based on the parent devices, if not provided by the
553 static void mtd_set_dev_defaults(struct mtd_info *mtd)
555 if (mtd->dev.parent) {
556 if (!mtd->owner && mtd->dev.parent->driver)
557 mtd->owner = mtd->dev.parent->driver->owner;
559 mtd->name = dev_name(mtd->dev.parent);
561 pr_debug("mtd device won't show a device symlink in sysfs\n");
566 * mtd_device_parse_register - parse partitions and register an MTD device.
568 * @mtd: the MTD device to register
569 * @types: the list of MTD partition probes to try, see
570 * 'parse_mtd_partitions()' for more information
571 * @parser_data: MTD partition parser-specific data
572 * @parts: fallback partition information to register, if parsing fails;
573 * only valid if %nr_parts > %0
574 * @nr_parts: the number of partitions in parts, if zero then the full
575 * MTD device is registered if no partition info is found
577 * This function aggregates MTD partitions parsing (done by
578 * 'parse_mtd_partitions()') and MTD device and partitions registering. It
579 * basically follows the most common pattern found in many MTD drivers:
581 * * It first tries to probe partitions on MTD device @mtd using parsers
582 * specified in @types (if @types is %NULL, then the default list of parsers
583 * is used, see 'parse_mtd_partitions()' for more information). If none are
584 * found this functions tries to fallback to information specified in
586 * * If any partitioning info was found, this function registers the found
587 * partitions. If the MTD_PARTITIONED_MASTER option is set, then the device
588 * as a whole is registered first.
589 * * If no partitions were found this function just registers the MTD device
592 * Returns zero in case of success and a negative error code in case of failure.
594 int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types,
595 struct mtd_part_parser_data *parser_data,
596 const struct mtd_partition *parts,
599 struct mtd_partitions parsed;
602 mtd_set_dev_defaults(mtd);
604 memset(&parsed, 0, sizeof(parsed));
606 ret = parse_mtd_partitions(mtd, types, &parsed, parser_data);
607 if ((ret < 0 || parsed.nr_parts == 0) && parts && nr_parts) {
608 /* Fall back to driver-provided partitions */
609 parsed = (struct mtd_partitions){
611 .nr_parts = nr_parts,
613 } else if (ret < 0) {
614 /* Didn't come up with parsed OR fallback partitions */
615 pr_info("mtd: failed to find partitions; one or more parsers reports errors (%d)\n",
617 /* Don't abort on errors; we can still use unpartitioned MTD */
618 memset(&parsed, 0, sizeof(parsed));
621 ret = mtd_add_device_partitions(mtd, &parsed);
626 * FIXME: some drivers unfortunately call this function more than once.
627 * So we have to check if we've already assigned the reboot notifier.
629 * Generally, we can make multiple calls work for most cases, but it
630 * does cause problems with parse_mtd_partitions() above (e.g.,
631 * cmdlineparts will register partitions more than once).
633 WARN_ONCE(mtd->_reboot && mtd->reboot_notifier.notifier_call,
634 "MTD already registered\n");
635 if (mtd->_reboot && !mtd->reboot_notifier.notifier_call) {
636 mtd->reboot_notifier.notifier_call = mtd_reboot_notifier;
637 register_reboot_notifier(&mtd->reboot_notifier);
641 /* Cleanup any parsed partitions */
642 mtd_part_parser_cleanup(&parsed);
645 EXPORT_SYMBOL_GPL(mtd_device_parse_register);
648 * mtd_device_unregister - unregister an existing MTD device.
650 * @master: the MTD device to unregister. This will unregister both the master
651 * and any partitions if registered.
653 int mtd_device_unregister(struct mtd_info *master)
658 unregister_reboot_notifier(&master->reboot_notifier);
660 err = del_mtd_partitions(master);
664 if (!device_is_registered(&master->dev))
667 return del_mtd_device(master);
669 EXPORT_SYMBOL_GPL(mtd_device_unregister);
672 * register_mtd_user - register a 'user' of MTD devices.
673 * @new: pointer to notifier info structure
675 * Registers a pair of callbacks function to be called upon addition
676 * or removal of MTD devices. Causes the 'add' callback to be immediately
677 * invoked for each MTD device currently present in the system.
679 void register_mtd_user (struct mtd_notifier *new)
681 struct mtd_info *mtd;
683 mutex_lock(&mtd_table_mutex);
685 list_add(&new->list, &mtd_notifiers);
687 __module_get(THIS_MODULE);
689 mtd_for_each_device(mtd)
692 mutex_unlock(&mtd_table_mutex);
694 EXPORT_SYMBOL_GPL(register_mtd_user);
697 * unregister_mtd_user - unregister a 'user' of MTD devices.
698 * @old: pointer to notifier info structure
700 * Removes a callback function pair from the list of 'users' to be
701 * notified upon addition or removal of MTD devices. Causes the
702 * 'remove' callback to be immediately invoked for each MTD device
703 * currently present in the system.
705 int unregister_mtd_user (struct mtd_notifier *old)
707 struct mtd_info *mtd;
709 mutex_lock(&mtd_table_mutex);
711 module_put(THIS_MODULE);
713 mtd_for_each_device(mtd)
716 list_del(&old->list);
717 mutex_unlock(&mtd_table_mutex);
720 EXPORT_SYMBOL_GPL(unregister_mtd_user);
723 * get_mtd_device - obtain a validated handle for an MTD device
724 * @mtd: last known address of the required MTD device
725 * @num: internal device number of the required MTD device
727 * Given a number and NULL address, return the num'th entry in the device
728 * table, if any. Given an address and num == -1, search the device table
729 * for a device with that address and return if it's still present. Given
730 * both, return the num'th driver only if its address matches. Return
733 struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num)
735 struct mtd_info *ret = NULL, *other;
738 mutex_lock(&mtd_table_mutex);
741 mtd_for_each_device(other) {
747 } else if (num >= 0) {
748 ret = idr_find(&mtd_idr, num);
749 if (mtd && mtd != ret)
758 err = __get_mtd_device(ret);
762 mutex_unlock(&mtd_table_mutex);
765 EXPORT_SYMBOL_GPL(get_mtd_device);
768 int __get_mtd_device(struct mtd_info *mtd)
772 if (!try_module_get(mtd->owner))
775 if (mtd->_get_device) {
776 err = mtd->_get_device(mtd);
779 module_put(mtd->owner);
786 EXPORT_SYMBOL_GPL(__get_mtd_device);
789 * get_mtd_device_nm - obtain a validated handle for an MTD device by
791 * @name: MTD device name to open
793 * This function returns MTD device description structure in case of
794 * success and an error code in case of failure.
796 struct mtd_info *get_mtd_device_nm(const char *name)
799 struct mtd_info *mtd = NULL, *other;
801 mutex_lock(&mtd_table_mutex);
803 mtd_for_each_device(other) {
804 if (!strcmp(name, other->name)) {
813 err = __get_mtd_device(mtd);
817 mutex_unlock(&mtd_table_mutex);
821 mutex_unlock(&mtd_table_mutex);
824 EXPORT_SYMBOL_GPL(get_mtd_device_nm);
826 void put_mtd_device(struct mtd_info *mtd)
828 mutex_lock(&mtd_table_mutex);
829 __put_mtd_device(mtd);
830 mutex_unlock(&mtd_table_mutex);
833 EXPORT_SYMBOL_GPL(put_mtd_device);
835 void __put_mtd_device(struct mtd_info *mtd)
838 BUG_ON(mtd->usecount < 0);
840 if (mtd->_put_device)
841 mtd->_put_device(mtd);
843 module_put(mtd->owner);
845 EXPORT_SYMBOL_GPL(__put_mtd_device);
848 * Erase is an asynchronous operation. Device drivers are supposed
849 * to call instr->callback() whenever the operation completes, even
850 * if it completes with a failure.
851 * Callers are supposed to pass a callback function and wait for it
852 * to be called before writing to the block.
854 int mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
856 if (instr->addr >= mtd->size || instr->len > mtd->size - instr->addr)
858 if (!(mtd->flags & MTD_WRITEABLE))
860 instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
862 instr->state = MTD_ERASE_DONE;
863 mtd_erase_callback(instr);
866 ledtrig_mtd_activity();
867 return mtd->_erase(mtd, instr);
869 EXPORT_SYMBOL_GPL(mtd_erase);
872 * This stuff for eXecute-In-Place. phys is optional and may be set to NULL.
874 int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
875 void **virt, resource_size_t *phys)
883 if (from < 0 || from >= mtd->size || len > mtd->size - from)
887 return mtd->_point(mtd, from, len, retlen, virt, phys);
889 EXPORT_SYMBOL_GPL(mtd_point);
891 /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
892 int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
896 if (from < 0 || from >= mtd->size || len > mtd->size - from)
900 return mtd->_unpoint(mtd, from, len);
902 EXPORT_SYMBOL_GPL(mtd_unpoint);
905 * Allow NOMMU mmap() to directly map the device (if not NULL)
906 * - return the address to which the offset maps
907 * - return -ENOSYS to indicate refusal to do the mapping
909 unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
910 unsigned long offset, unsigned long flags)
912 if (!mtd->_get_unmapped_area)
914 if (offset >= mtd->size || len > mtd->size - offset)
916 return mtd->_get_unmapped_area(mtd, len, offset, flags);
918 EXPORT_SYMBOL_GPL(mtd_get_unmapped_area);
920 int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
925 if (from < 0 || from >= mtd->size || len > mtd->size - from)
930 ledtrig_mtd_activity();
932 * In the absence of an error, drivers return a non-negative integer
933 * representing the maximum number of bitflips that were corrected on
934 * any one ecc region (if applicable; zero otherwise).
936 ret_code = mtd->_read(mtd, from, len, retlen, buf);
937 if (unlikely(ret_code < 0))
939 if (mtd->ecc_strength == 0)
940 return 0; /* device lacks ecc */
941 return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
943 EXPORT_SYMBOL_GPL(mtd_read);
945 int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
949 if (to < 0 || to >= mtd->size || len > mtd->size - to)
951 if (!mtd->_write || !(mtd->flags & MTD_WRITEABLE))
955 ledtrig_mtd_activity();
956 return mtd->_write(mtd, to, len, retlen, buf);
958 EXPORT_SYMBOL_GPL(mtd_write);
961 * In blackbox flight recorder like scenarios we want to make successful writes
962 * in interrupt context. panic_write() is only intended to be called when its
963 * known the kernel is about to panic and we need the write to succeed. Since
964 * the kernel is not going to be running for much longer, this function can
965 * break locks and delay to ensure the write succeeds (but not sleep).
967 int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
971 if (!mtd->_panic_write)
973 if (to < 0 || to >= mtd->size || len > mtd->size - to)
975 if (!(mtd->flags & MTD_WRITEABLE))
979 return mtd->_panic_write(mtd, to, len, retlen, buf);
981 EXPORT_SYMBOL_GPL(mtd_panic_write);
983 int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops)
986 ops->retlen = ops->oobretlen = 0;
990 ledtrig_mtd_activity();
992 * In cases where ops->datbuf != NULL, mtd->_read_oob() has semantics
993 * similar to mtd->_read(), returning a non-negative integer
994 * representing max bitflips. In other cases, mtd->_read_oob() may
995 * return -EUCLEAN. In all cases, perform similar logic to mtd_read().
997 ret_code = mtd->_read_oob(mtd, from, ops);
998 if (unlikely(ret_code < 0))
1000 if (mtd->ecc_strength == 0)
1001 return 0; /* device lacks ecc */
1002 return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
1004 EXPORT_SYMBOL_GPL(mtd_read_oob);
1006 int mtd_write_oob(struct mtd_info *mtd, loff_t to,
1007 struct mtd_oob_ops *ops)
1009 ops->retlen = ops->oobretlen = 0;
1010 if (!mtd->_write_oob)
1012 if (!(mtd->flags & MTD_WRITEABLE))
1014 ledtrig_mtd_activity();
1015 return mtd->_write_oob(mtd, to, ops);
1017 EXPORT_SYMBOL_GPL(mtd_write_oob);
1020 * Method to access the protection register area, present in some flash
1021 * devices. The user data is one time programmable but the factory data is read
1024 int mtd_get_fact_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
1025 struct otp_info *buf)
1027 if (!mtd->_get_fact_prot_info)
1031 return mtd->_get_fact_prot_info(mtd, len, retlen, buf);
1033 EXPORT_SYMBOL_GPL(mtd_get_fact_prot_info);
1035 int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
1036 size_t *retlen, u_char *buf)
1039 if (!mtd->_read_fact_prot_reg)
1043 return mtd->_read_fact_prot_reg(mtd, from, len, retlen, buf);
1045 EXPORT_SYMBOL_GPL(mtd_read_fact_prot_reg);
1047 int mtd_get_user_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
1048 struct otp_info *buf)
1050 if (!mtd->_get_user_prot_info)
1054 return mtd->_get_user_prot_info(mtd, len, retlen, buf);
1056 EXPORT_SYMBOL_GPL(mtd_get_user_prot_info);
1058 int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
1059 size_t *retlen, u_char *buf)
1062 if (!mtd->_read_user_prot_reg)
1066 return mtd->_read_user_prot_reg(mtd, from, len, retlen, buf);
1068 EXPORT_SYMBOL_GPL(mtd_read_user_prot_reg);
1070 int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
1071 size_t *retlen, u_char *buf)
1076 if (!mtd->_write_user_prot_reg)
1080 ret = mtd->_write_user_prot_reg(mtd, to, len, retlen, buf);
1085 * If no data could be written at all, we are out of memory and
1086 * must return -ENOSPC.
1088 return (*retlen) ? 0 : -ENOSPC;
1090 EXPORT_SYMBOL_GPL(mtd_write_user_prot_reg);
1092 int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len)
1094 if (!mtd->_lock_user_prot_reg)
1098 return mtd->_lock_user_prot_reg(mtd, from, len);
1100 EXPORT_SYMBOL_GPL(mtd_lock_user_prot_reg);
1102 /* Chip-supported device locking */
1103 int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
1107 if (ofs < 0 || ofs >= mtd->size || len > mtd->size - ofs)
1111 return mtd->_lock(mtd, ofs, len);
1113 EXPORT_SYMBOL_GPL(mtd_lock);
1115 int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
1119 if (ofs < 0 || ofs >= mtd->size || len > mtd->size - ofs)
1123 return mtd->_unlock(mtd, ofs, len);
1125 EXPORT_SYMBOL_GPL(mtd_unlock);
1127 int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
1129 if (!mtd->_is_locked)
1131 if (ofs < 0 || ofs >= mtd->size || len > mtd->size - ofs)
1135 return mtd->_is_locked(mtd, ofs, len);
1137 EXPORT_SYMBOL_GPL(mtd_is_locked);
1139 int mtd_block_isreserved(struct mtd_info *mtd, loff_t ofs)
1141 if (ofs < 0 || ofs >= mtd->size)
1143 if (!mtd->_block_isreserved)
1145 return mtd->_block_isreserved(mtd, ofs);
1147 EXPORT_SYMBOL_GPL(mtd_block_isreserved);
1149 int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs)
1151 if (ofs < 0 || ofs >= mtd->size)
1153 if (!mtd->_block_isbad)
1155 return mtd->_block_isbad(mtd, ofs);
1157 EXPORT_SYMBOL_GPL(mtd_block_isbad);
1159 int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs)
1161 if (!mtd->_block_markbad)
1163 if (ofs < 0 || ofs >= mtd->size)
1165 if (!(mtd->flags & MTD_WRITEABLE))
1167 return mtd->_block_markbad(mtd, ofs);
1169 EXPORT_SYMBOL_GPL(mtd_block_markbad);
1172 * default_mtd_writev - the default writev method
1173 * @mtd: mtd device description object pointer
1174 * @vecs: the vectors to write
1175 * @count: count of vectors in @vecs
1176 * @to: the MTD device offset to write to
1177 * @retlen: on exit contains the count of bytes written to the MTD device.
1179 * This function returns zero in case of success and a negative error code in
1182 static int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
1183 unsigned long count, loff_t to, size_t *retlen)
1186 size_t totlen = 0, thislen;
1189 for (i = 0; i < count; i++) {
1190 if (!vecs[i].iov_len)
1192 ret = mtd_write(mtd, to, vecs[i].iov_len, &thislen,
1195 if (ret || thislen != vecs[i].iov_len)
1197 to += vecs[i].iov_len;
1204 * mtd_writev - the vector-based MTD write method
1205 * @mtd: mtd device description object pointer
1206 * @vecs: the vectors to write
1207 * @count: count of vectors in @vecs
1208 * @to: the MTD device offset to write to
1209 * @retlen: on exit contains the count of bytes written to the MTD device.
1211 * This function returns zero in case of success and a negative error code in
1214 int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
1215 unsigned long count, loff_t to, size_t *retlen)
1218 if (!(mtd->flags & MTD_WRITEABLE))
1221 return default_mtd_writev(mtd, vecs, count, to, retlen);
1222 return mtd->_writev(mtd, vecs, count, to, retlen);
1224 EXPORT_SYMBOL_GPL(mtd_writev);
1227 * mtd_kmalloc_up_to - allocate a contiguous buffer up to the specified size
1228 * @mtd: mtd device description object pointer
1229 * @size: a pointer to the ideal or maximum size of the allocation, points
1230 * to the actual allocation size on success.
1232 * This routine attempts to allocate a contiguous kernel buffer up to
1233 * the specified size, backing off the size of the request exponentially
1234 * until the request succeeds or until the allocation size falls below
1235 * the system page size. This attempts to make sure it does not adversely
1236 * impact system performance, so when allocating more than one page, we
1237 * ask the memory allocator to avoid re-trying, swapping, writing back
1238 * or performing I/O.
1240 * Note, this function also makes sure that the allocated buffer is aligned to
1241 * the MTD device's min. I/O unit, i.e. the "mtd->writesize" value.
1243 * This is called, for example by mtd_{read,write} and jffs2_scan_medium,
1244 * to handle smaller (i.e. degraded) buffer allocations under low- or
1245 * fragmented-memory situations where such reduced allocations, from a
1246 * requested ideal, are allowed.
1248 * Returns a pointer to the allocated buffer on success; otherwise, NULL.
1250 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size)
1252 gfp_t flags = __GFP_NOWARN | __GFP_DIRECT_RECLAIM | __GFP_NORETRY;
1253 size_t min_alloc = max_t(size_t, mtd->writesize, PAGE_SIZE);
1256 *size = min_t(size_t, *size, KMALLOC_MAX_SIZE);
1258 while (*size > min_alloc) {
1259 kbuf = kmalloc(*size, flags);
1264 *size = ALIGN(*size, mtd->writesize);
1268 * For the last resort allocation allow 'kmalloc()' to do all sorts of
1269 * things (write-back, dropping caches, etc) by using GFP_KERNEL.
1271 return kmalloc(*size, GFP_KERNEL);
1273 EXPORT_SYMBOL_GPL(mtd_kmalloc_up_to);
1275 #ifdef CONFIG_PROC_FS
1277 /*====================================================================*/
1278 /* Support for /proc/mtd */
1280 static int mtd_proc_show(struct seq_file *m, void *v)
1282 struct mtd_info *mtd;
1284 seq_puts(m, "dev: size erasesize name\n");
1285 mutex_lock(&mtd_table_mutex);
1286 mtd_for_each_device(mtd) {
1287 seq_printf(m, "mtd%d: %8.8llx %8.8x \"%s\"\n",
1288 mtd->index, (unsigned long long)mtd->size,
1289 mtd->erasesize, mtd->name);
1291 mutex_unlock(&mtd_table_mutex);
1295 static int mtd_proc_open(struct inode *inode, struct file *file)
1297 return single_open(file, mtd_proc_show, NULL);
1300 static const struct file_operations mtd_proc_ops = {
1301 .open = mtd_proc_open,
1303 .llseek = seq_lseek,
1304 .release = single_release,
1306 #endif /* CONFIG_PROC_FS */
1308 /*====================================================================*/
1311 static int __init mtd_bdi_init(struct backing_dev_info *bdi, const char *name)
1315 ret = bdi_init(bdi);
1317 ret = bdi_register(bdi, NULL, "%s", name);
1325 static struct proc_dir_entry *proc_mtd;
1327 static int __init init_mtd(void)
1331 ret = class_register(&mtd_class);
1335 ret = mtd_bdi_init(&mtd_bdi, "mtd");
1339 proc_mtd = proc_create("mtd", 0, NULL, &mtd_proc_ops);
1341 ret = init_mtdchar();
1349 remove_proc_entry("mtd", NULL);
1351 class_unregister(&mtd_class);
1353 pr_err("Error registering mtd class or bdi: %d\n", ret);
1357 static void __exit cleanup_mtd(void)
1361 remove_proc_entry("mtd", NULL);
1362 class_unregister(&mtd_class);
1363 bdi_destroy(&mtd_bdi);
1364 idr_destroy(&mtd_idr);
1367 module_init(init_mtd);
1368 module_exit(cleanup_mtd);
1370 MODULE_LICENSE("GPL");
1371 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
1372 MODULE_DESCRIPTION("Core MTD registration and access routines");