2 * Core registration and callback routines for MTD
5 * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>
6 * Copyright © 2006 Red Hat UK Limited
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
24 #include <linux/module.h>
25 #include <linux/kernel.h>
26 #include <linux/ptrace.h>
27 #include <linux/seq_file.h>
28 #include <linux/string.h>
29 #include <linux/timer.h>
30 #include <linux/major.h>
32 #include <linux/err.h>
33 #include <linux/ioctl.h>
34 #include <linux/init.h>
35 #include <linux/proc_fs.h>
36 #include <linux/idr.h>
37 #include <linux/backing-dev.h>
38 #include <linux/gfp.h>
39 #include <linux/slab.h>
41 #include <linux/mtd/mtd.h>
42 #include <linux/mtd/partitions.h>
47 * backing device capabilities for non-mappable devices (such as NAND flash)
48 * - permits private mappings, copies are taken of the data
50 static struct backing_dev_info mtd_bdi_unmappable = {
51 .capabilities = BDI_CAP_MAP_COPY,
55 * backing device capabilities for R/O mappable devices (such as ROM)
56 * - permits private mappings, copies are taken of the data
57 * - permits non-writable shared mappings
59 static struct backing_dev_info mtd_bdi_ro_mappable = {
60 .capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT |
61 BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP),
65 * backing device capabilities for writable mappable devices (such as RAM)
66 * - permits private mappings, copies are taken of the data
67 * - permits non-writable shared mappings
69 static struct backing_dev_info mtd_bdi_rw_mappable = {
70 .capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT |
71 BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP |
75 static int mtd_cls_suspend(struct device *dev, pm_message_t state);
76 static int mtd_cls_resume(struct device *dev);
78 static struct class mtd_class = {
81 .suspend = mtd_cls_suspend,
82 .resume = mtd_cls_resume,
85 static DEFINE_IDR(mtd_idr);
87 /* These are exported solely for the purpose of mtd_blkdevs.c. You
88 should not use them for _anything_ else */
89 DEFINE_MUTEX(mtd_table_mutex);
90 EXPORT_SYMBOL_GPL(mtd_table_mutex);
92 struct mtd_info *__mtd_next_device(int i)
94 return idr_get_next(&mtd_idr, &i);
96 EXPORT_SYMBOL_GPL(__mtd_next_device);
98 static LIST_HEAD(mtd_notifiers);
101 #define MTD_DEVT(index) MKDEV(MTD_CHAR_MAJOR, (index)*2)
103 /* REVISIT once MTD uses the driver model better, whoever allocates
104 * the mtd_info will probably want to use the release() hook...
106 static void mtd_release(struct device *dev)
108 struct mtd_info __maybe_unused *mtd = dev_get_drvdata(dev);
109 dev_t index = MTD_DEVT(mtd->index);
111 /* remove /dev/mtdXro node if needed */
113 device_destroy(&mtd_class, index + 1);
116 static int mtd_cls_suspend(struct device *dev, pm_message_t state)
118 struct mtd_info *mtd = dev_get_drvdata(dev);
120 return mtd ? mtd_suspend(mtd) : 0;
123 static int mtd_cls_resume(struct device *dev)
125 struct mtd_info *mtd = dev_get_drvdata(dev);
132 static ssize_t mtd_type_show(struct device *dev,
133 struct device_attribute *attr, char *buf)
135 struct mtd_info *mtd = dev_get_drvdata(dev);
164 return snprintf(buf, PAGE_SIZE, "%s\n", type);
166 static DEVICE_ATTR(type, S_IRUGO, mtd_type_show, NULL);
168 static ssize_t mtd_flags_show(struct device *dev,
169 struct device_attribute *attr, char *buf)
171 struct mtd_info *mtd = dev_get_drvdata(dev);
173 return snprintf(buf, PAGE_SIZE, "0x%lx\n", (unsigned long)mtd->flags);
176 static DEVICE_ATTR(flags, S_IRUGO, mtd_flags_show, NULL);
178 static ssize_t mtd_size_show(struct device *dev,
179 struct device_attribute *attr, char *buf)
181 struct mtd_info *mtd = dev_get_drvdata(dev);
183 return snprintf(buf, PAGE_SIZE, "%llu\n",
184 (unsigned long long)mtd->size);
187 static DEVICE_ATTR(size, S_IRUGO, mtd_size_show, NULL);
189 static ssize_t mtd_erasesize_show(struct device *dev,
190 struct device_attribute *attr, char *buf)
192 struct mtd_info *mtd = dev_get_drvdata(dev);
194 return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->erasesize);
197 static DEVICE_ATTR(erasesize, S_IRUGO, mtd_erasesize_show, NULL);
199 static ssize_t mtd_writesize_show(struct device *dev,
200 struct device_attribute *attr, char *buf)
202 struct mtd_info *mtd = dev_get_drvdata(dev);
204 return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->writesize);
207 static DEVICE_ATTR(writesize, S_IRUGO, mtd_writesize_show, NULL);
209 static ssize_t mtd_subpagesize_show(struct device *dev,
210 struct device_attribute *attr, char *buf)
212 struct mtd_info *mtd = dev_get_drvdata(dev);
213 unsigned int subpagesize = mtd->writesize >> mtd->subpage_sft;
215 return snprintf(buf, PAGE_SIZE, "%u\n", subpagesize);
218 static DEVICE_ATTR(subpagesize, S_IRUGO, mtd_subpagesize_show, NULL);
220 static ssize_t mtd_oobsize_show(struct device *dev,
221 struct device_attribute *attr, char *buf)
223 struct mtd_info *mtd = dev_get_drvdata(dev);
225 return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->oobsize);
228 static DEVICE_ATTR(oobsize, S_IRUGO, mtd_oobsize_show, NULL);
230 static ssize_t mtd_numeraseregions_show(struct device *dev,
231 struct device_attribute *attr, char *buf)
233 struct mtd_info *mtd = dev_get_drvdata(dev);
235 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->numeraseregions);
238 static DEVICE_ATTR(numeraseregions, S_IRUGO, mtd_numeraseregions_show,
241 static ssize_t mtd_name_show(struct device *dev,
242 struct device_attribute *attr, char *buf)
244 struct mtd_info *mtd = dev_get_drvdata(dev);
246 return snprintf(buf, PAGE_SIZE, "%s\n", mtd->name);
249 static DEVICE_ATTR(name, S_IRUGO, mtd_name_show, NULL);
251 static ssize_t mtd_ecc_strength_show(struct device *dev,
252 struct device_attribute *attr, char *buf)
254 struct mtd_info *mtd = dev_get_drvdata(dev);
256 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->ecc_strength);
258 static DEVICE_ATTR(ecc_strength, S_IRUGO, mtd_ecc_strength_show, NULL);
260 static ssize_t mtd_bitflip_threshold_show(struct device *dev,
261 struct device_attribute *attr,
264 struct mtd_info *mtd = dev_get_drvdata(dev);
266 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->bitflip_threshold);
269 static ssize_t mtd_bitflip_threshold_store(struct device *dev,
270 struct device_attribute *attr,
271 const char *buf, size_t count)
273 struct mtd_info *mtd = dev_get_drvdata(dev);
274 unsigned int bitflip_threshold;
277 retval = kstrtouint(buf, 0, &bitflip_threshold);
281 mtd->bitflip_threshold = bitflip_threshold;
284 static DEVICE_ATTR(bitflip_threshold, S_IRUGO | S_IWUSR,
285 mtd_bitflip_threshold_show,
286 mtd_bitflip_threshold_store);
288 static struct attribute *mtd_attrs[] = {
290 &dev_attr_flags.attr,
292 &dev_attr_erasesize.attr,
293 &dev_attr_writesize.attr,
294 &dev_attr_subpagesize.attr,
295 &dev_attr_oobsize.attr,
296 &dev_attr_numeraseregions.attr,
298 &dev_attr_ecc_strength.attr,
299 &dev_attr_bitflip_threshold.attr,
303 static struct attribute_group mtd_group = {
307 static const struct attribute_group *mtd_groups[] = {
312 static struct device_type mtd_devtype = {
314 .groups = mtd_groups,
315 .release = mtd_release,
319 * add_mtd_device - register an MTD device
320 * @mtd: pointer to new MTD device info structure
322 * Add a device to the list of MTD devices present in the system, and
323 * notify each currently active MTD 'user' of its arrival. Returns
324 * zero on success or 1 on failure, which currently will only happen
325 * if there is insufficient memory or a sysfs error.
328 int add_mtd_device(struct mtd_info *mtd)
330 struct mtd_notifier *not;
333 if (!mtd->backing_dev_info) {
336 mtd->backing_dev_info = &mtd_bdi_rw_mappable;
339 mtd->backing_dev_info = &mtd_bdi_ro_mappable;
342 mtd->backing_dev_info = &mtd_bdi_unmappable;
347 BUG_ON(mtd->writesize == 0);
348 mutex_lock(&mtd_table_mutex);
350 i = idr_alloc(&mtd_idr, mtd, 0, 0, GFP_KERNEL);
357 /* default value if not set by driver */
358 if (mtd->bitflip_threshold == 0)
359 mtd->bitflip_threshold = mtd->ecc_strength;
361 if (is_power_of_2(mtd->erasesize))
362 mtd->erasesize_shift = ffs(mtd->erasesize) - 1;
364 mtd->erasesize_shift = 0;
366 if (is_power_of_2(mtd->writesize))
367 mtd->writesize_shift = ffs(mtd->writesize) - 1;
369 mtd->writesize_shift = 0;
371 mtd->erasesize_mask = (1 << mtd->erasesize_shift) - 1;
372 mtd->writesize_mask = (1 << mtd->writesize_shift) - 1;
374 /* Some chips always power up locked. Unlock them now */
375 if ((mtd->flags & MTD_WRITEABLE) && (mtd->flags & MTD_POWERUP_LOCK)) {
376 error = mtd_unlock(mtd, 0, mtd->size);
377 if (error && error != -EOPNOTSUPP)
379 "%s: unlock failed, writes may not work\n",
383 /* Caller should have set dev.parent to match the
386 mtd->dev.type = &mtd_devtype;
387 mtd->dev.class = &mtd_class;
388 mtd->dev.devt = MTD_DEVT(i);
389 dev_set_name(&mtd->dev, "mtd%d", i);
390 dev_set_drvdata(&mtd->dev, mtd);
391 if (device_register(&mtd->dev) != 0)
395 device_create(&mtd_class, mtd->dev.parent,
399 pr_debug("mtd: Giving out device %d to %s\n", i, mtd->name);
400 /* No need to get a refcount on the module containing
401 the notifier, since we hold the mtd_table_mutex */
402 list_for_each_entry(not, &mtd_notifiers, list)
405 mutex_unlock(&mtd_table_mutex);
406 /* We _know_ we aren't being removed, because
407 our caller is still holding us here. So none
408 of this try_ nonsense, and no bitching about it
410 __module_get(THIS_MODULE);
414 idr_remove(&mtd_idr, i);
416 mutex_unlock(&mtd_table_mutex);
421 * del_mtd_device - unregister an MTD device
422 * @mtd: pointer to MTD device info structure
424 * Remove a device from the list of MTD devices present in the system,
425 * and notify each currently active MTD 'user' of its departure.
426 * Returns zero on success or 1 on failure, which currently will happen
427 * if the requested device does not appear to be present in the list.
430 int del_mtd_device(struct mtd_info *mtd)
433 struct mtd_notifier *not;
435 mutex_lock(&mtd_table_mutex);
437 if (idr_find(&mtd_idr, mtd->index) != mtd) {
442 /* No need to get a refcount on the module containing
443 the notifier, since we hold the mtd_table_mutex */
444 list_for_each_entry(not, &mtd_notifiers, list)
448 printk(KERN_NOTICE "Removing MTD device #%d (%s) with use count %d\n",
449 mtd->index, mtd->name, mtd->usecount);
452 device_unregister(&mtd->dev);
454 idr_remove(&mtd_idr, mtd->index);
456 module_put(THIS_MODULE);
461 mutex_unlock(&mtd_table_mutex);
466 * mtd_device_parse_register - parse partitions and register an MTD device.
468 * @mtd: the MTD device to register
469 * @types: the list of MTD partition probes to try, see
470 * 'parse_mtd_partitions()' for more information
471 * @parser_data: MTD partition parser-specific data
472 * @parts: fallback partition information to register, if parsing fails;
473 * only valid if %nr_parts > %0
474 * @nr_parts: the number of partitions in parts, if zero then the full
475 * MTD device is registered if no partition info is found
477 * This function aggregates MTD partitions parsing (done by
478 * 'parse_mtd_partitions()') and MTD device and partitions registering. It
479 * basically follows the most common pattern found in many MTD drivers:
481 * * It first tries to probe partitions on MTD device @mtd using parsers
482 * specified in @types (if @types is %NULL, then the default list of parsers
483 * is used, see 'parse_mtd_partitions()' for more information). If none are
484 * found this functions tries to fallback to information specified in
486 * * If any partitioning info was found, this function registers the found
488 * * If no partitions were found this function just registers the MTD device
491 * Returns zero in case of success and a negative error code in case of failure.
493 int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types,
494 struct mtd_part_parser_data *parser_data,
495 const struct mtd_partition *parts,
499 struct mtd_partition *real_parts;
501 err = parse_mtd_partitions(mtd, types, &real_parts, parser_data);
502 if (err <= 0 && nr_parts && parts) {
503 real_parts = kmemdup(parts, sizeof(*parts) * nr_parts,
512 err = add_mtd_partitions(mtd, real_parts, err);
514 } else if (err == 0) {
515 err = add_mtd_device(mtd);
522 EXPORT_SYMBOL_GPL(mtd_device_parse_register);
525 * mtd_device_unregister - unregister an existing MTD device.
527 * @master: the MTD device to unregister. This will unregister both the master
528 * and any partitions if registered.
530 int mtd_device_unregister(struct mtd_info *master)
534 err = del_mtd_partitions(master);
538 if (!device_is_registered(&master->dev))
541 return del_mtd_device(master);
543 EXPORT_SYMBOL_GPL(mtd_device_unregister);
546 * register_mtd_user - register a 'user' of MTD devices.
547 * @new: pointer to notifier info structure
549 * Registers a pair of callbacks function to be called upon addition
550 * or removal of MTD devices. Causes the 'add' callback to be immediately
551 * invoked for each MTD device currently present in the system.
553 void register_mtd_user (struct mtd_notifier *new)
555 struct mtd_info *mtd;
557 mutex_lock(&mtd_table_mutex);
559 list_add(&new->list, &mtd_notifiers);
561 __module_get(THIS_MODULE);
563 mtd_for_each_device(mtd)
566 mutex_unlock(&mtd_table_mutex);
568 EXPORT_SYMBOL_GPL(register_mtd_user);
571 * unregister_mtd_user - unregister a 'user' of MTD devices.
572 * @old: pointer to notifier info structure
574 * Removes a callback function pair from the list of 'users' to be
575 * notified upon addition or removal of MTD devices. Causes the
576 * 'remove' callback to be immediately invoked for each MTD device
577 * currently present in the system.
579 int unregister_mtd_user (struct mtd_notifier *old)
581 struct mtd_info *mtd;
583 mutex_lock(&mtd_table_mutex);
585 module_put(THIS_MODULE);
587 mtd_for_each_device(mtd)
590 list_del(&old->list);
591 mutex_unlock(&mtd_table_mutex);
594 EXPORT_SYMBOL_GPL(unregister_mtd_user);
597 * get_mtd_device - obtain a validated handle for an MTD device
598 * @mtd: last known address of the required MTD device
599 * @num: internal device number of the required MTD device
601 * Given a number and NULL address, return the num'th entry in the device
602 * table, if any. Given an address and num == -1, search the device table
603 * for a device with that address and return if it's still present. Given
604 * both, return the num'th driver only if its address matches. Return
607 struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num)
609 struct mtd_info *ret = NULL, *other;
612 mutex_lock(&mtd_table_mutex);
615 mtd_for_each_device(other) {
621 } else if (num >= 0) {
622 ret = idr_find(&mtd_idr, num);
623 if (mtd && mtd != ret)
632 err = __get_mtd_device(ret);
636 mutex_unlock(&mtd_table_mutex);
639 EXPORT_SYMBOL_GPL(get_mtd_device);
642 int __get_mtd_device(struct mtd_info *mtd)
646 if (!try_module_get(mtd->owner))
649 if (mtd->_get_device) {
650 err = mtd->_get_device(mtd);
653 module_put(mtd->owner);
660 EXPORT_SYMBOL_GPL(__get_mtd_device);
663 * get_mtd_device_nm - obtain a validated handle for an MTD device by
665 * @name: MTD device name to open
667 * This function returns MTD device description structure in case of
668 * success and an error code in case of failure.
670 struct mtd_info *get_mtd_device_nm(const char *name)
673 struct mtd_info *mtd = NULL, *other;
675 mutex_lock(&mtd_table_mutex);
677 mtd_for_each_device(other) {
678 if (!strcmp(name, other->name)) {
687 err = __get_mtd_device(mtd);
691 mutex_unlock(&mtd_table_mutex);
695 mutex_unlock(&mtd_table_mutex);
698 EXPORT_SYMBOL_GPL(get_mtd_device_nm);
700 void put_mtd_device(struct mtd_info *mtd)
702 mutex_lock(&mtd_table_mutex);
703 __put_mtd_device(mtd);
704 mutex_unlock(&mtd_table_mutex);
707 EXPORT_SYMBOL_GPL(put_mtd_device);
709 void __put_mtd_device(struct mtd_info *mtd)
712 BUG_ON(mtd->usecount < 0);
714 if (mtd->_put_device)
715 mtd->_put_device(mtd);
717 module_put(mtd->owner);
719 EXPORT_SYMBOL_GPL(__put_mtd_device);
722 * Erase is an asynchronous operation. Device drivers are supposed
723 * to call instr->callback() whenever the operation completes, even
724 * if it completes with a failure.
725 * Callers are supposed to pass a callback function and wait for it
726 * to be called before writing to the block.
728 int mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
730 if (instr->addr > mtd->size || instr->len > mtd->size - instr->addr)
732 if (!(mtd->flags & MTD_WRITEABLE))
734 instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
736 instr->state = MTD_ERASE_DONE;
737 mtd_erase_callback(instr);
740 return mtd->_erase(mtd, instr);
742 EXPORT_SYMBOL_GPL(mtd_erase);
745 * This stuff for eXecute-In-Place. phys is optional and may be set to NULL.
747 int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
748 void **virt, resource_size_t *phys)
756 if (from < 0 || from > mtd->size || len > mtd->size - from)
760 return mtd->_point(mtd, from, len, retlen, virt, phys);
762 EXPORT_SYMBOL_GPL(mtd_point);
764 /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
765 int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
769 if (from < 0 || from > mtd->size || len > mtd->size - from)
773 return mtd->_unpoint(mtd, from, len);
775 EXPORT_SYMBOL_GPL(mtd_unpoint);
778 * Allow NOMMU mmap() to directly map the device (if not NULL)
779 * - return the address to which the offset maps
780 * - return -ENOSYS to indicate refusal to do the mapping
782 unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
783 unsigned long offset, unsigned long flags)
785 if (!mtd->_get_unmapped_area)
787 if (offset > mtd->size || len > mtd->size - offset)
789 return mtd->_get_unmapped_area(mtd, len, offset, flags);
791 EXPORT_SYMBOL_GPL(mtd_get_unmapped_area);
793 int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
798 if (from < 0 || from > mtd->size || len > mtd->size - from)
804 * In the absence of an error, drivers return a non-negative integer
805 * representing the maximum number of bitflips that were corrected on
806 * any one ecc region (if applicable; zero otherwise).
808 ret_code = mtd->_read(mtd, from, len, retlen, buf);
809 if (unlikely(ret_code < 0))
811 if (mtd->ecc_strength == 0)
812 return 0; /* device lacks ecc */
813 return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
815 EXPORT_SYMBOL_GPL(mtd_read);
817 int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
821 if (to < 0 || to > mtd->size || len > mtd->size - to)
823 if (!mtd->_write || !(mtd->flags & MTD_WRITEABLE))
827 return mtd->_write(mtd, to, len, retlen, buf);
829 EXPORT_SYMBOL_GPL(mtd_write);
832 * In blackbox flight recorder like scenarios we want to make successful writes
833 * in interrupt context. panic_write() is only intended to be called when its
834 * known the kernel is about to panic and we need the write to succeed. Since
835 * the kernel is not going to be running for much longer, this function can
836 * break locks and delay to ensure the write succeeds (but not sleep).
838 int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
842 if (!mtd->_panic_write)
844 if (to < 0 || to > mtd->size || len > mtd->size - to)
846 if (!(mtd->flags & MTD_WRITEABLE))
850 return mtd->_panic_write(mtd, to, len, retlen, buf);
852 EXPORT_SYMBOL_GPL(mtd_panic_write);
854 int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops)
857 ops->retlen = ops->oobretlen = 0;
861 * In cases where ops->datbuf != NULL, mtd->_read_oob() has semantics
862 * similar to mtd->_read(), returning a non-negative integer
863 * representing max bitflips. In other cases, mtd->_read_oob() may
864 * return -EUCLEAN. In all cases, perform similar logic to mtd_read().
866 ret_code = mtd->_read_oob(mtd, from, ops);
867 if (unlikely(ret_code < 0))
869 if (mtd->ecc_strength == 0)
870 return 0; /* device lacks ecc */
871 return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
873 EXPORT_SYMBOL_GPL(mtd_read_oob);
876 * Method to access the protection register area, present in some flash
877 * devices. The user data is one time programmable but the factory data is read
880 int mtd_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
883 if (!mtd->_get_fact_prot_info)
887 return mtd->_get_fact_prot_info(mtd, buf, len);
889 EXPORT_SYMBOL_GPL(mtd_get_fact_prot_info);
891 int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
892 size_t *retlen, u_char *buf)
895 if (!mtd->_read_fact_prot_reg)
899 return mtd->_read_fact_prot_reg(mtd, from, len, retlen, buf);
901 EXPORT_SYMBOL_GPL(mtd_read_fact_prot_reg);
903 int mtd_get_user_prot_info(struct mtd_info *mtd, struct otp_info *buf,
906 if (!mtd->_get_user_prot_info)
910 return mtd->_get_user_prot_info(mtd, buf, len);
912 EXPORT_SYMBOL_GPL(mtd_get_user_prot_info);
914 int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
915 size_t *retlen, u_char *buf)
918 if (!mtd->_read_user_prot_reg)
922 return mtd->_read_user_prot_reg(mtd, from, len, retlen, buf);
924 EXPORT_SYMBOL_GPL(mtd_read_user_prot_reg);
926 int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
927 size_t *retlen, u_char *buf)
930 if (!mtd->_write_user_prot_reg)
934 return mtd->_write_user_prot_reg(mtd, to, len, retlen, buf);
936 EXPORT_SYMBOL_GPL(mtd_write_user_prot_reg);
938 int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len)
940 if (!mtd->_lock_user_prot_reg)
944 return mtd->_lock_user_prot_reg(mtd, from, len);
946 EXPORT_SYMBOL_GPL(mtd_lock_user_prot_reg);
948 /* Chip-supported device locking */
949 int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
953 if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
957 return mtd->_lock(mtd, ofs, len);
959 EXPORT_SYMBOL_GPL(mtd_lock);
961 int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
965 if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
969 return mtd->_unlock(mtd, ofs, len);
971 EXPORT_SYMBOL_GPL(mtd_unlock);
973 int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
975 if (!mtd->_is_locked)
977 if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
981 return mtd->_is_locked(mtd, ofs, len);
983 EXPORT_SYMBOL_GPL(mtd_is_locked);
985 int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs)
987 if (!mtd->_block_isbad)
989 if (ofs < 0 || ofs > mtd->size)
991 return mtd->_block_isbad(mtd, ofs);
993 EXPORT_SYMBOL_GPL(mtd_block_isbad);
995 int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs)
997 if (!mtd->_block_markbad)
999 if (ofs < 0 || ofs > mtd->size)
1001 if (!(mtd->flags & MTD_WRITEABLE))
1003 return mtd->_block_markbad(mtd, ofs);
1005 EXPORT_SYMBOL_GPL(mtd_block_markbad);
1008 * default_mtd_writev - the default writev method
1009 * @mtd: mtd device description object pointer
1010 * @vecs: the vectors to write
1011 * @count: count of vectors in @vecs
1012 * @to: the MTD device offset to write to
1013 * @retlen: on exit contains the count of bytes written to the MTD device.
1015 * This function returns zero in case of success and a negative error code in
1018 static int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
1019 unsigned long count, loff_t to, size_t *retlen)
1022 size_t totlen = 0, thislen;
1025 for (i = 0; i < count; i++) {
1026 if (!vecs[i].iov_len)
1028 ret = mtd_write(mtd, to, vecs[i].iov_len, &thislen,
1031 if (ret || thislen != vecs[i].iov_len)
1033 to += vecs[i].iov_len;
1040 * mtd_writev - the vector-based MTD write method
1041 * @mtd: mtd device description object pointer
1042 * @vecs: the vectors to write
1043 * @count: count of vectors in @vecs
1044 * @to: the MTD device offset to write to
1045 * @retlen: on exit contains the count of bytes written to the MTD device.
1047 * This function returns zero in case of success and a negative error code in
1050 int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
1051 unsigned long count, loff_t to, size_t *retlen)
1054 if (!(mtd->flags & MTD_WRITEABLE))
1057 return default_mtd_writev(mtd, vecs, count, to, retlen);
1058 return mtd->_writev(mtd, vecs, count, to, retlen);
1060 EXPORT_SYMBOL_GPL(mtd_writev);
1063 * mtd_kmalloc_up_to - allocate a contiguous buffer up to the specified size
1064 * @mtd: mtd device description object pointer
1065 * @size: a pointer to the ideal or maximum size of the allocation, points
1066 * to the actual allocation size on success.
1068 * This routine attempts to allocate a contiguous kernel buffer up to
1069 * the specified size, backing off the size of the request exponentially
1070 * until the request succeeds or until the allocation size falls below
1071 * the system page size. This attempts to make sure it does not adversely
1072 * impact system performance, so when allocating more than one page, we
1073 * ask the memory allocator to avoid re-trying, swapping, writing back
1074 * or performing I/O.
1076 * Note, this function also makes sure that the allocated buffer is aligned to
1077 * the MTD device's min. I/O unit, i.e. the "mtd->writesize" value.
1079 * This is called, for example by mtd_{read,write} and jffs2_scan_medium,
1080 * to handle smaller (i.e. degraded) buffer allocations under low- or
1081 * fragmented-memory situations where such reduced allocations, from a
1082 * requested ideal, are allowed.
1084 * Returns a pointer to the allocated buffer on success; otherwise, NULL.
1086 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size)
1088 gfp_t flags = __GFP_NOWARN | __GFP_WAIT |
1089 __GFP_NORETRY | __GFP_NO_KSWAPD;
1090 size_t min_alloc = max_t(size_t, mtd->writesize, PAGE_SIZE);
1093 *size = min_t(size_t, *size, KMALLOC_MAX_SIZE);
1095 while (*size > min_alloc) {
1096 kbuf = kmalloc(*size, flags);
1101 *size = ALIGN(*size, mtd->writesize);
1105 * For the last resort allocation allow 'kmalloc()' to do all sorts of
1106 * things (write-back, dropping caches, etc) by using GFP_KERNEL.
1108 return kmalloc(*size, GFP_KERNEL);
1110 EXPORT_SYMBOL_GPL(mtd_kmalloc_up_to);
1112 #ifdef CONFIG_PROC_FS
1114 /*====================================================================*/
1115 /* Support for /proc/mtd */
1117 static int mtd_proc_show(struct seq_file *m, void *v)
1119 struct mtd_info *mtd;
1121 seq_puts(m, "dev: size erasesize name\n");
1122 mutex_lock(&mtd_table_mutex);
1123 mtd_for_each_device(mtd) {
1124 seq_printf(m, "mtd%d: %8.8llx %8.8x \"%s\"\n",
1125 mtd->index, (unsigned long long)mtd->size,
1126 mtd->erasesize, mtd->name);
1128 mutex_unlock(&mtd_table_mutex);
1132 static int mtd_proc_open(struct inode *inode, struct file *file)
1134 return single_open(file, mtd_proc_show, NULL);
1137 static const struct file_operations mtd_proc_ops = {
1138 .open = mtd_proc_open,
1140 .llseek = seq_lseek,
1141 .release = single_release,
1144 /*====================================================================*/
1145 /* Support for /proc/mtdbdblk */
1147 static int mtd_proc_bdblk_show(struct seq_file *m, void *v)
1149 struct mtd_info *mtd;
1151 seq_puts(m, "dev:name badblocks\n");
1152 mutex_lock(&mtd_table_mutex);
1153 mtd_for_each_device(mtd) {
1154 seq_printf(m, "mtd%d:%-12s %x\n",
1155 mtd->index, mtd->name,
1156 mtd->ecc_stats.badblocks);
1158 mutex_unlock(&mtd_table_mutex);
1162 static int mtd_proc_bdblk_open(struct inode *inode, struct file *file)
1164 return single_open(file, mtd_proc_bdblk_show, NULL);
1167 static const struct file_operations mtd_proc_bdblk_ops = {
1168 .open = mtd_proc_bdblk_open,
1170 .llseek = seq_lseek,
1171 .release = single_release,
1173 #endif /* CONFIG_PROC_FS */
1175 /*====================================================================*/
1178 static int __init mtd_bdi_init(struct backing_dev_info *bdi, const char *name)
1182 ret = bdi_init(bdi);
1184 ret = bdi_register(bdi, NULL, name);
1192 static struct proc_dir_entry *proc_mtd;
1193 static struct proc_dir_entry *proc_mtdbdblk;
1195 static int __init init_mtd(void)
1199 ret = class_register(&mtd_class);
1203 ret = mtd_bdi_init(&mtd_bdi_unmappable, "mtd-unmap");
1207 ret = mtd_bdi_init(&mtd_bdi_ro_mappable, "mtd-romap");
1211 ret = mtd_bdi_init(&mtd_bdi_rw_mappable, "mtd-rwmap");
1215 proc_mtd = proc_create("mtd", 0, NULL, &mtd_proc_ops);
1216 proc_mtdbdblk = proc_create("mtdbdblk", 0, NULL, &mtd_proc_bdblk_ops);
1218 ret = init_mtdchar();
1226 remove_proc_entry("mtd", NULL);
1228 remove_proc_entry("mtdbdblk", NULL);
1230 bdi_destroy(&mtd_bdi_ro_mappable);
1232 bdi_destroy(&mtd_bdi_unmappable);
1234 class_unregister(&mtd_class);
1236 pr_err("Error registering mtd class or bdi: %d\n", ret);
1240 static void __exit cleanup_mtd(void)
1244 remove_proc_entry("mtd", NULL);
1246 remove_proc_entry("mtdbdblk", NULL);
1247 class_unregister(&mtd_class);
1248 bdi_destroy(&mtd_bdi_unmappable);
1249 bdi_destroy(&mtd_bdi_ro_mappable);
1250 bdi_destroy(&mtd_bdi_rw_mappable);
1253 module_init(init_mtd);
1254 module_exit(cleanup_mtd);
1256 MODULE_LICENSE("GPL");
1257 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
1258 MODULE_DESCRIPTION("Core MTD registration and access routines");