2 * Core registration and callback routines for MTD
5 * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>
6 * Copyright © 2006 Red Hat UK Limited
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
24 #include <linux/module.h>
25 #include <linux/kernel.h>
26 #include <linux/ptrace.h>
27 #include <linux/seq_file.h>
28 #include <linux/string.h>
29 #include <linux/timer.h>
30 #include <linux/major.h>
32 #include <linux/err.h>
33 #include <linux/ioctl.h>
34 #include <linux/init.h>
35 #include <linux/proc_fs.h>
36 #include <linux/idr.h>
37 #include <linux/backing-dev.h>
38 #include <linux/gfp.h>
39 #include <linux/slab.h>
40 #include <linux/major.h>
42 #include <linux/mtd/mtd.h>
43 #include <linux/mtd/partitions.h>
48 * backing device capabilities for non-mappable devices (such as NAND flash)
49 * - permits private mappings, copies are taken of the data
51 static struct backing_dev_info mtd_bdi_unmappable = {
52 .capabilities = BDI_CAP_MAP_COPY,
56 * backing device capabilities for R/O mappable devices (such as ROM)
57 * - permits private mappings, copies are taken of the data
58 * - permits non-writable shared mappings
60 static struct backing_dev_info mtd_bdi_ro_mappable = {
61 .capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT |
62 BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP),
66 * backing device capabilities for writable mappable devices (such as RAM)
67 * - permits private mappings, copies are taken of the data
68 * - permits non-writable shared mappings
70 static struct backing_dev_info mtd_bdi_rw_mappable = {
71 .capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT |
72 BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP |
76 static int mtd_cls_suspend(struct device *dev, pm_message_t state);
77 static int mtd_cls_resume(struct device *dev);
79 static struct class mtd_class = {
82 .suspend = mtd_cls_suspend,
83 .resume = mtd_cls_resume,
86 static DEFINE_IDR(mtd_idr);
88 /* These are exported solely for the purpose of mtd_blkdevs.c. You
89 should not use them for _anything_ else */
90 DEFINE_MUTEX(mtd_table_mutex);
91 EXPORT_SYMBOL_GPL(mtd_table_mutex);
93 struct mtd_info *__mtd_next_device(int i)
95 return idr_get_next(&mtd_idr, &i);
97 EXPORT_SYMBOL_GPL(__mtd_next_device);
99 static LIST_HEAD(mtd_notifiers);
102 #define MTD_DEVT(index) MKDEV(MTD_CHAR_MAJOR, (index)*2)
104 /* REVISIT once MTD uses the driver model better, whoever allocates
105 * the mtd_info will probably want to use the release() hook...
107 static void mtd_release(struct device *dev)
109 struct mtd_info __maybe_unused *mtd = dev_get_drvdata(dev);
110 dev_t index = MTD_DEVT(mtd->index);
112 /* remove /dev/mtdXro node if needed */
114 device_destroy(&mtd_class, index + 1);
117 static int mtd_cls_suspend(struct device *dev, pm_message_t state)
119 struct mtd_info *mtd = dev_get_drvdata(dev);
121 return mtd ? mtd_suspend(mtd) : 0;
124 static int mtd_cls_resume(struct device *dev)
126 struct mtd_info *mtd = dev_get_drvdata(dev);
133 static ssize_t mtd_type_show(struct device *dev,
134 struct device_attribute *attr, char *buf)
136 struct mtd_info *mtd = dev_get_drvdata(dev);
161 case MTD_MLCNANDFLASH:
168 return snprintf(buf, PAGE_SIZE, "%s\n", type);
170 static DEVICE_ATTR(type, S_IRUGO, mtd_type_show, NULL);
172 static ssize_t mtd_flags_show(struct device *dev,
173 struct device_attribute *attr, char *buf)
175 struct mtd_info *mtd = dev_get_drvdata(dev);
177 return snprintf(buf, PAGE_SIZE, "0x%lx\n", (unsigned long)mtd->flags);
180 static DEVICE_ATTR(flags, S_IRUGO, mtd_flags_show, NULL);
182 static ssize_t mtd_size_show(struct device *dev,
183 struct device_attribute *attr, char *buf)
185 struct mtd_info *mtd = dev_get_drvdata(dev);
187 return snprintf(buf, PAGE_SIZE, "%llu\n",
188 (unsigned long long)mtd->size);
191 static DEVICE_ATTR(size, S_IRUGO, mtd_size_show, NULL);
193 static ssize_t mtd_erasesize_show(struct device *dev,
194 struct device_attribute *attr, char *buf)
196 struct mtd_info *mtd = dev_get_drvdata(dev);
198 return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->erasesize);
201 static DEVICE_ATTR(erasesize, S_IRUGO, mtd_erasesize_show, NULL);
203 static ssize_t mtd_writesize_show(struct device *dev,
204 struct device_attribute *attr, char *buf)
206 struct mtd_info *mtd = dev_get_drvdata(dev);
208 return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->writesize);
211 static DEVICE_ATTR(writesize, S_IRUGO, mtd_writesize_show, NULL);
213 static ssize_t mtd_subpagesize_show(struct device *dev,
214 struct device_attribute *attr, char *buf)
216 struct mtd_info *mtd = dev_get_drvdata(dev);
217 unsigned int subpagesize = mtd->writesize >> mtd->subpage_sft;
219 return snprintf(buf, PAGE_SIZE, "%u\n", subpagesize);
222 static DEVICE_ATTR(subpagesize, S_IRUGO, mtd_subpagesize_show, NULL);
224 static ssize_t mtd_oobsize_show(struct device *dev,
225 struct device_attribute *attr, char *buf)
227 struct mtd_info *mtd = dev_get_drvdata(dev);
229 return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->oobsize);
232 static DEVICE_ATTR(oobsize, S_IRUGO, mtd_oobsize_show, NULL);
234 static ssize_t mtd_numeraseregions_show(struct device *dev,
235 struct device_attribute *attr, char *buf)
237 struct mtd_info *mtd = dev_get_drvdata(dev);
239 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->numeraseregions);
242 static DEVICE_ATTR(numeraseregions, S_IRUGO, mtd_numeraseregions_show,
245 static ssize_t mtd_name_show(struct device *dev,
246 struct device_attribute *attr, char *buf)
248 struct mtd_info *mtd = dev_get_drvdata(dev);
250 return snprintf(buf, PAGE_SIZE, "%s\n", mtd->name);
253 static DEVICE_ATTR(name, S_IRUGO, mtd_name_show, NULL);
255 static ssize_t mtd_ecc_strength_show(struct device *dev,
256 struct device_attribute *attr, char *buf)
258 struct mtd_info *mtd = dev_get_drvdata(dev);
260 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->ecc_strength);
262 static DEVICE_ATTR(ecc_strength, S_IRUGO, mtd_ecc_strength_show, NULL);
264 static ssize_t mtd_bitflip_threshold_show(struct device *dev,
265 struct device_attribute *attr,
268 struct mtd_info *mtd = dev_get_drvdata(dev);
270 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->bitflip_threshold);
273 static ssize_t mtd_bitflip_threshold_store(struct device *dev,
274 struct device_attribute *attr,
275 const char *buf, size_t count)
277 struct mtd_info *mtd = dev_get_drvdata(dev);
278 unsigned int bitflip_threshold;
281 retval = kstrtouint(buf, 0, &bitflip_threshold);
285 mtd->bitflip_threshold = bitflip_threshold;
288 static DEVICE_ATTR(bitflip_threshold, S_IRUGO | S_IWUSR,
289 mtd_bitflip_threshold_show,
290 mtd_bitflip_threshold_store);
292 static ssize_t mtd_ecc_step_size_show(struct device *dev,
293 struct device_attribute *attr, char *buf)
295 struct mtd_info *mtd = dev_get_drvdata(dev);
297 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->ecc_step_size);
300 static DEVICE_ATTR(ecc_step_size, S_IRUGO, mtd_ecc_step_size_show, NULL);
302 static struct attribute *mtd_attrs[] = {
304 &dev_attr_flags.attr,
306 &dev_attr_erasesize.attr,
307 &dev_attr_writesize.attr,
308 &dev_attr_subpagesize.attr,
309 &dev_attr_oobsize.attr,
310 &dev_attr_numeraseregions.attr,
312 &dev_attr_ecc_strength.attr,
313 &dev_attr_ecc_step_size.attr,
314 &dev_attr_bitflip_threshold.attr,
318 static struct attribute_group mtd_group = {
322 static const struct attribute_group *mtd_groups[] = {
327 static struct device_type mtd_devtype = {
329 .groups = mtd_groups,
330 .release = mtd_release,
334 * add_mtd_device - register an MTD device
335 * @mtd: pointer to new MTD device info structure
337 * Add a device to the list of MTD devices present in the system, and
338 * notify each currently active MTD 'user' of its arrival. Returns
339 * zero on success or 1 on failure, which currently will only happen
340 * if there is insufficient memory or a sysfs error.
343 int add_mtd_device(struct mtd_info *mtd)
345 struct mtd_notifier *not;
348 if (!mtd->backing_dev_info) {
351 mtd->backing_dev_info = &mtd_bdi_rw_mappable;
354 mtd->backing_dev_info = &mtd_bdi_ro_mappable;
357 mtd->backing_dev_info = &mtd_bdi_unmappable;
362 BUG_ON(mtd->writesize == 0);
363 mutex_lock(&mtd_table_mutex);
365 i = idr_alloc(&mtd_idr, mtd, 0, 0, GFP_KERNEL);
372 /* default value if not set by driver */
373 if (mtd->bitflip_threshold == 0)
374 mtd->bitflip_threshold = mtd->ecc_strength;
376 if (is_power_of_2(mtd->erasesize))
377 mtd->erasesize_shift = ffs(mtd->erasesize) - 1;
379 mtd->erasesize_shift = 0;
381 if (is_power_of_2(mtd->writesize))
382 mtd->writesize_shift = ffs(mtd->writesize) - 1;
384 mtd->writesize_shift = 0;
386 mtd->erasesize_mask = (1 << mtd->erasesize_shift) - 1;
387 mtd->writesize_mask = (1 << mtd->writesize_shift) - 1;
389 /* Some chips always power up locked. Unlock them now */
390 if ((mtd->flags & MTD_WRITEABLE) && (mtd->flags & MTD_POWERUP_LOCK)) {
391 error = mtd_unlock(mtd, 0, mtd->size);
392 if (error && error != -EOPNOTSUPP)
394 "%s: unlock failed, writes may not work\n",
398 /* Caller should have set dev.parent to match the
401 mtd->dev.type = &mtd_devtype;
402 mtd->dev.class = &mtd_class;
403 mtd->dev.devt = MTD_DEVT(i);
404 dev_set_name(&mtd->dev, "mtd%d", i);
405 dev_set_drvdata(&mtd->dev, mtd);
406 if (device_register(&mtd->dev) != 0)
410 device_create(&mtd_class, mtd->dev.parent,
414 pr_debug("mtd: Giving out device %d to %s\n", i, mtd->name);
415 /* No need to get a refcount on the module containing
416 the notifier, since we hold the mtd_table_mutex */
417 list_for_each_entry(not, &mtd_notifiers, list)
420 mutex_unlock(&mtd_table_mutex);
421 /* We _know_ we aren't being removed, because
422 our caller is still holding us here. So none
423 of this try_ nonsense, and no bitching about it
425 __module_get(THIS_MODULE);
429 idr_remove(&mtd_idr, i);
431 mutex_unlock(&mtd_table_mutex);
436 * del_mtd_device - unregister an MTD device
437 * @mtd: pointer to MTD device info structure
439 * Remove a device from the list of MTD devices present in the system,
440 * and notify each currently active MTD 'user' of its departure.
441 * Returns zero on success or 1 on failure, which currently will happen
442 * if the requested device does not appear to be present in the list.
445 int del_mtd_device(struct mtd_info *mtd)
448 struct mtd_notifier *not;
450 mutex_lock(&mtd_table_mutex);
452 if (idr_find(&mtd_idr, mtd->index) != mtd) {
457 /* No need to get a refcount on the module containing
458 the notifier, since we hold the mtd_table_mutex */
459 list_for_each_entry(not, &mtd_notifiers, list)
463 printk(KERN_NOTICE "Removing MTD device #%d (%s) with use count %d\n",
464 mtd->index, mtd->name, mtd->usecount);
467 device_unregister(&mtd->dev);
469 idr_remove(&mtd_idr, mtd->index);
471 module_put(THIS_MODULE);
476 mutex_unlock(&mtd_table_mutex);
481 * mtd_device_parse_register - parse partitions and register an MTD device.
483 * @mtd: the MTD device to register
484 * @types: the list of MTD partition probes to try, see
485 * 'parse_mtd_partitions()' for more information
486 * @parser_data: MTD partition parser-specific data
487 * @parts: fallback partition information to register, if parsing fails;
488 * only valid if %nr_parts > %0
489 * @nr_parts: the number of partitions in parts, if zero then the full
490 * MTD device is registered if no partition info is found
492 * This function aggregates MTD partitions parsing (done by
493 * 'parse_mtd_partitions()') and MTD device and partitions registering. It
494 * basically follows the most common pattern found in many MTD drivers:
496 * * It first tries to probe partitions on MTD device @mtd using parsers
497 * specified in @types (if @types is %NULL, then the default list of parsers
498 * is used, see 'parse_mtd_partitions()' for more information). If none are
499 * found this functions tries to fallback to information specified in
501 * * If any partitioning info was found, this function registers the found
503 * * If no partitions were found this function just registers the MTD device
506 * Returns zero in case of success and a negative error code in case of failure.
508 int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types,
509 struct mtd_part_parser_data *parser_data,
510 const struct mtd_partition *parts,
514 struct mtd_partition *real_parts;
516 err = parse_mtd_partitions(mtd, types, &real_parts, parser_data);
517 if (err <= 0 && nr_parts && parts) {
518 real_parts = kmemdup(parts, sizeof(*parts) * nr_parts,
527 err = add_mtd_partitions(mtd, real_parts, err);
529 } else if (err == 0) {
530 err = add_mtd_device(mtd);
537 EXPORT_SYMBOL_GPL(mtd_device_parse_register);
540 * mtd_device_unregister - unregister an existing MTD device.
542 * @master: the MTD device to unregister. This will unregister both the master
543 * and any partitions if registered.
545 int mtd_device_unregister(struct mtd_info *master)
549 err = del_mtd_partitions(master);
553 if (!device_is_registered(&master->dev))
556 return del_mtd_device(master);
558 EXPORT_SYMBOL_GPL(mtd_device_unregister);
561 * register_mtd_user - register a 'user' of MTD devices.
562 * @new: pointer to notifier info structure
564 * Registers a pair of callbacks function to be called upon addition
565 * or removal of MTD devices. Causes the 'add' callback to be immediately
566 * invoked for each MTD device currently present in the system.
568 void register_mtd_user (struct mtd_notifier *new)
570 struct mtd_info *mtd;
572 mutex_lock(&mtd_table_mutex);
574 list_add(&new->list, &mtd_notifiers);
576 __module_get(THIS_MODULE);
578 mtd_for_each_device(mtd)
581 mutex_unlock(&mtd_table_mutex);
583 EXPORT_SYMBOL_GPL(register_mtd_user);
586 * unregister_mtd_user - unregister a 'user' of MTD devices.
587 * @old: pointer to notifier info structure
589 * Removes a callback function pair from the list of 'users' to be
590 * notified upon addition or removal of MTD devices. Causes the
591 * 'remove' callback to be immediately invoked for each MTD device
592 * currently present in the system.
594 int unregister_mtd_user (struct mtd_notifier *old)
596 struct mtd_info *mtd;
598 mutex_lock(&mtd_table_mutex);
600 module_put(THIS_MODULE);
602 mtd_for_each_device(mtd)
605 list_del(&old->list);
606 mutex_unlock(&mtd_table_mutex);
609 EXPORT_SYMBOL_GPL(unregister_mtd_user);
612 * get_mtd_device - obtain a validated handle for an MTD device
613 * @mtd: last known address of the required MTD device
614 * @num: internal device number of the required MTD device
616 * Given a number and NULL address, return the num'th entry in the device
617 * table, if any. Given an address and num == -1, search the device table
618 * for a device with that address and return if it's still present. Given
619 * both, return the num'th driver only if its address matches. Return
622 struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num)
624 struct mtd_info *ret = NULL, *other;
627 mutex_lock(&mtd_table_mutex);
630 mtd_for_each_device(other) {
636 } else if (num >= 0) {
637 ret = idr_find(&mtd_idr, num);
638 if (mtd && mtd != ret)
647 err = __get_mtd_device(ret);
651 mutex_unlock(&mtd_table_mutex);
654 EXPORT_SYMBOL_GPL(get_mtd_device);
657 int __get_mtd_device(struct mtd_info *mtd)
661 if (!try_module_get(mtd->owner))
664 if (mtd->_get_device) {
665 err = mtd->_get_device(mtd);
668 module_put(mtd->owner);
675 EXPORT_SYMBOL_GPL(__get_mtd_device);
678 * get_mtd_device_nm - obtain a validated handle for an MTD device by
680 * @name: MTD device name to open
682 * This function returns MTD device description structure in case of
683 * success and an error code in case of failure.
685 struct mtd_info *get_mtd_device_nm(const char *name)
688 struct mtd_info *mtd = NULL, *other;
690 mutex_lock(&mtd_table_mutex);
692 mtd_for_each_device(other) {
693 if (!strcmp(name, other->name)) {
702 err = __get_mtd_device(mtd);
706 mutex_unlock(&mtd_table_mutex);
710 mutex_unlock(&mtd_table_mutex);
713 EXPORT_SYMBOL_GPL(get_mtd_device_nm);
715 void put_mtd_device(struct mtd_info *mtd)
717 mutex_lock(&mtd_table_mutex);
718 __put_mtd_device(mtd);
719 mutex_unlock(&mtd_table_mutex);
722 EXPORT_SYMBOL_GPL(put_mtd_device);
724 void __put_mtd_device(struct mtd_info *mtd)
727 BUG_ON(mtd->usecount < 0);
729 if (mtd->_put_device)
730 mtd->_put_device(mtd);
732 module_put(mtd->owner);
734 EXPORT_SYMBOL_GPL(__put_mtd_device);
737 * Erase is an asynchronous operation. Device drivers are supposed
738 * to call instr->callback() whenever the operation completes, even
739 * if it completes with a failure.
740 * Callers are supposed to pass a callback function and wait for it
741 * to be called before writing to the block.
743 int mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
745 if (instr->addr > mtd->size || instr->len > mtd->size - instr->addr)
747 if (!(mtd->flags & MTD_WRITEABLE))
749 instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
751 instr->state = MTD_ERASE_DONE;
752 mtd_erase_callback(instr);
755 return mtd->_erase(mtd, instr);
757 EXPORT_SYMBOL_GPL(mtd_erase);
760 * This stuff for eXecute-In-Place. phys is optional and may be set to NULL.
762 int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
763 void **virt, resource_size_t *phys)
771 if (from < 0 || from > mtd->size || len > mtd->size - from)
775 return mtd->_point(mtd, from, len, retlen, virt, phys);
777 EXPORT_SYMBOL_GPL(mtd_point);
779 /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
780 int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
784 if (from < 0 || from > mtd->size || len > mtd->size - from)
788 return mtd->_unpoint(mtd, from, len);
790 EXPORT_SYMBOL_GPL(mtd_unpoint);
793 * Allow NOMMU mmap() to directly map the device (if not NULL)
794 * - return the address to which the offset maps
795 * - return -ENOSYS to indicate refusal to do the mapping
797 unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
798 unsigned long offset, unsigned long flags)
800 if (!mtd->_get_unmapped_area)
802 if (offset > mtd->size || len > mtd->size - offset)
804 return mtd->_get_unmapped_area(mtd, len, offset, flags);
806 EXPORT_SYMBOL_GPL(mtd_get_unmapped_area);
808 int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
813 if (from < 0 || from > mtd->size || len > mtd->size - from)
819 * In the absence of an error, drivers return a non-negative integer
820 * representing the maximum number of bitflips that were corrected on
821 * any one ecc region (if applicable; zero otherwise).
823 ret_code = mtd->_read(mtd, from, len, retlen, buf);
824 if (unlikely(ret_code < 0))
826 if (mtd->ecc_strength == 0)
827 return 0; /* device lacks ecc */
828 return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
830 EXPORT_SYMBOL_GPL(mtd_read);
832 int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
836 if (to < 0 || to > mtd->size || len > mtd->size - to)
838 if (!mtd->_write || !(mtd->flags & MTD_WRITEABLE))
842 return mtd->_write(mtd, to, len, retlen, buf);
844 EXPORT_SYMBOL_GPL(mtd_write);
847 * In blackbox flight recorder like scenarios we want to make successful writes
848 * in interrupt context. panic_write() is only intended to be called when its
849 * known the kernel is about to panic and we need the write to succeed. Since
850 * the kernel is not going to be running for much longer, this function can
851 * break locks and delay to ensure the write succeeds (but not sleep).
853 int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
857 if (!mtd->_panic_write)
859 if (to < 0 || to > mtd->size || len > mtd->size - to)
861 if (!(mtd->flags & MTD_WRITEABLE))
865 return mtd->_panic_write(mtd, to, len, retlen, buf);
867 EXPORT_SYMBOL_GPL(mtd_panic_write);
869 int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops)
872 ops->retlen = ops->oobretlen = 0;
876 * In cases where ops->datbuf != NULL, mtd->_read_oob() has semantics
877 * similar to mtd->_read(), returning a non-negative integer
878 * representing max bitflips. In other cases, mtd->_read_oob() may
879 * return -EUCLEAN. In all cases, perform similar logic to mtd_read().
881 ret_code = mtd->_read_oob(mtd, from, ops);
882 if (unlikely(ret_code < 0))
884 if (mtd->ecc_strength == 0)
885 return 0; /* device lacks ecc */
886 return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
888 EXPORT_SYMBOL_GPL(mtd_read_oob);
891 * Method to access the protection register area, present in some flash
892 * devices. The user data is one time programmable but the factory data is read
895 int mtd_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
898 if (!mtd->_get_fact_prot_info)
902 return mtd->_get_fact_prot_info(mtd, buf, len);
904 EXPORT_SYMBOL_GPL(mtd_get_fact_prot_info);
906 int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
907 size_t *retlen, u_char *buf)
910 if (!mtd->_read_fact_prot_reg)
914 return mtd->_read_fact_prot_reg(mtd, from, len, retlen, buf);
916 EXPORT_SYMBOL_GPL(mtd_read_fact_prot_reg);
918 int mtd_get_user_prot_info(struct mtd_info *mtd, struct otp_info *buf,
921 if (!mtd->_get_user_prot_info)
925 return mtd->_get_user_prot_info(mtd, buf, len);
927 EXPORT_SYMBOL_GPL(mtd_get_user_prot_info);
929 int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
930 size_t *retlen, u_char *buf)
933 if (!mtd->_read_user_prot_reg)
937 return mtd->_read_user_prot_reg(mtd, from, len, retlen, buf);
939 EXPORT_SYMBOL_GPL(mtd_read_user_prot_reg);
941 int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
942 size_t *retlen, u_char *buf)
945 if (!mtd->_write_user_prot_reg)
949 return mtd->_write_user_prot_reg(mtd, to, len, retlen, buf);
951 EXPORT_SYMBOL_GPL(mtd_write_user_prot_reg);
953 int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len)
955 if (!mtd->_lock_user_prot_reg)
959 return mtd->_lock_user_prot_reg(mtd, from, len);
961 EXPORT_SYMBOL_GPL(mtd_lock_user_prot_reg);
963 /* Chip-supported device locking */
964 int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
968 if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
972 return mtd->_lock(mtd, ofs, len);
974 EXPORT_SYMBOL_GPL(mtd_lock);
976 int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
980 if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
984 return mtd->_unlock(mtd, ofs, len);
986 EXPORT_SYMBOL_GPL(mtd_unlock);
988 int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
990 if (!mtd->_is_locked)
992 if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
996 return mtd->_is_locked(mtd, ofs, len);
998 EXPORT_SYMBOL_GPL(mtd_is_locked);
1000 int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs)
1002 if (!mtd->_block_isbad)
1004 if (ofs < 0 || ofs > mtd->size)
1006 return mtd->_block_isbad(mtd, ofs);
1008 EXPORT_SYMBOL_GPL(mtd_block_isbad);
1010 int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs)
1012 if (!mtd->_block_markbad)
1014 if (ofs < 0 || ofs > mtd->size)
1016 if (!(mtd->flags & MTD_WRITEABLE))
1018 return mtd->_block_markbad(mtd, ofs);
1020 EXPORT_SYMBOL_GPL(mtd_block_markbad);
1023 * default_mtd_writev - the default writev method
1024 * @mtd: mtd device description object pointer
1025 * @vecs: the vectors to write
1026 * @count: count of vectors in @vecs
1027 * @to: the MTD device offset to write to
1028 * @retlen: on exit contains the count of bytes written to the MTD device.
1030 * This function returns zero in case of success and a negative error code in
1033 static int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
1034 unsigned long count, loff_t to, size_t *retlen)
1037 size_t totlen = 0, thislen;
1040 for (i = 0; i < count; i++) {
1041 if (!vecs[i].iov_len)
1043 ret = mtd_write(mtd, to, vecs[i].iov_len, &thislen,
1046 if (ret || thislen != vecs[i].iov_len)
1048 to += vecs[i].iov_len;
1055 * mtd_writev - the vector-based MTD write method
1056 * @mtd: mtd device description object pointer
1057 * @vecs: the vectors to write
1058 * @count: count of vectors in @vecs
1059 * @to: the MTD device offset to write to
1060 * @retlen: on exit contains the count of bytes written to the MTD device.
1062 * This function returns zero in case of success and a negative error code in
1065 int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
1066 unsigned long count, loff_t to, size_t *retlen)
1069 if (!(mtd->flags & MTD_WRITEABLE))
1072 return default_mtd_writev(mtd, vecs, count, to, retlen);
1073 return mtd->_writev(mtd, vecs, count, to, retlen);
1075 EXPORT_SYMBOL_GPL(mtd_writev);
1078 * mtd_kmalloc_up_to - allocate a contiguous buffer up to the specified size
1079 * @mtd: mtd device description object pointer
1080 * @size: a pointer to the ideal or maximum size of the allocation, points
1081 * to the actual allocation size on success.
1083 * This routine attempts to allocate a contiguous kernel buffer up to
1084 * the specified size, backing off the size of the request exponentially
1085 * until the request succeeds or until the allocation size falls below
1086 * the system page size. This attempts to make sure it does not adversely
1087 * impact system performance, so when allocating more than one page, we
1088 * ask the memory allocator to avoid re-trying, swapping, writing back
1089 * or performing I/O.
1091 * Note, this function also makes sure that the allocated buffer is aligned to
1092 * the MTD device's min. I/O unit, i.e. the "mtd->writesize" value.
1094 * This is called, for example by mtd_{read,write} and jffs2_scan_medium,
1095 * to handle smaller (i.e. degraded) buffer allocations under low- or
1096 * fragmented-memory situations where such reduced allocations, from a
1097 * requested ideal, are allowed.
1099 * Returns a pointer to the allocated buffer on success; otherwise, NULL.
1101 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size)
1103 gfp_t flags = __GFP_NOWARN | __GFP_WAIT |
1104 __GFP_NORETRY | __GFP_NO_KSWAPD;
1105 size_t min_alloc = max_t(size_t, mtd->writesize, PAGE_SIZE);
1108 *size = min_t(size_t, *size, KMALLOC_MAX_SIZE);
1110 while (*size > min_alloc) {
1111 kbuf = kmalloc(*size, flags);
1116 *size = ALIGN(*size, mtd->writesize);
1120 * For the last resort allocation allow 'kmalloc()' to do all sorts of
1121 * things (write-back, dropping caches, etc) by using GFP_KERNEL.
1123 return kmalloc(*size, GFP_KERNEL);
1125 EXPORT_SYMBOL_GPL(mtd_kmalloc_up_to);
1127 #ifdef CONFIG_PROC_FS
1129 /*====================================================================*/
1130 /* Support for /proc/mtd */
1132 static int mtd_proc_show(struct seq_file *m, void *v)
1134 struct mtd_info *mtd;
1136 seq_puts(m, "dev: size erasesize name\n");
1137 mutex_lock(&mtd_table_mutex);
1138 mtd_for_each_device(mtd) {
1139 seq_printf(m, "mtd%d: %8.8llx %8.8x \"%s\"\n",
1140 mtd->index, (unsigned long long)mtd->size,
1141 mtd->erasesize, mtd->name);
1143 mutex_unlock(&mtd_table_mutex);
1147 static int mtd_proc_open(struct inode *inode, struct file *file)
1149 return single_open(file, mtd_proc_show, NULL);
1152 static const struct file_operations mtd_proc_ops = {
1153 .open = mtd_proc_open,
1155 .llseek = seq_lseek,
1156 .release = single_release,
1158 #endif /* CONFIG_PROC_FS */
1160 /*====================================================================*/
1163 static int __init mtd_bdi_init(struct backing_dev_info *bdi, const char *name)
1167 ret = bdi_init(bdi);
1169 ret = bdi_register(bdi, NULL, "%s", name);
1177 static struct proc_dir_entry *proc_mtd;
1179 static int __init init_mtd(void)
1183 ret = class_register(&mtd_class);
1187 ret = mtd_bdi_init(&mtd_bdi_unmappable, "mtd-unmap");
1191 ret = mtd_bdi_init(&mtd_bdi_ro_mappable, "mtd-romap");
1195 ret = mtd_bdi_init(&mtd_bdi_rw_mappable, "mtd-rwmap");
1199 proc_mtd = proc_create("mtd", 0, NULL, &mtd_proc_ops);
1201 ret = init_mtdchar();
1209 remove_proc_entry("mtd", NULL);
1211 bdi_destroy(&mtd_bdi_ro_mappable);
1213 bdi_destroy(&mtd_bdi_unmappable);
1215 class_unregister(&mtd_class);
1217 pr_err("Error registering mtd class or bdi: %d\n", ret);
1221 static void __exit cleanup_mtd(void)
1225 remove_proc_entry("mtd", NULL);
1226 class_unregister(&mtd_class);
1227 bdi_destroy(&mtd_bdi_unmappable);
1228 bdi_destroy(&mtd_bdi_ro_mappable);
1229 bdi_destroy(&mtd_bdi_rw_mappable);
1232 module_init(init_mtd);
1233 module_exit(cleanup_mtd);
1235 MODULE_LICENSE("GPL");
1236 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
1237 MODULE_DESCRIPTION("Core MTD registration and access routines");