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>
46 * backing device capabilities for non-mappable devices (such as NAND flash)
47 * - permits private mappings, copies are taken of the data
49 static struct backing_dev_info mtd_bdi_unmappable = {
50 .capabilities = BDI_CAP_MAP_COPY,
54 * backing device capabilities for R/O mappable devices (such as ROM)
55 * - permits private mappings, copies are taken of the data
56 * - permits non-writable shared mappings
58 static struct backing_dev_info mtd_bdi_ro_mappable = {
59 .capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT |
60 BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP),
64 * backing device capabilities for writable mappable devices (such as RAM)
65 * - permits private mappings, copies are taken of the data
66 * - permits non-writable shared mappings
68 static struct backing_dev_info mtd_bdi_rw_mappable = {
69 .capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT |
70 BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP |
74 static int mtd_cls_suspend(struct device *dev, pm_message_t state);
75 static int mtd_cls_resume(struct device *dev);
77 static struct class mtd_class = {
80 .suspend = mtd_cls_suspend,
81 .resume = mtd_cls_resume,
84 static DEFINE_IDR(mtd_idr);
86 /* These are exported solely for the purpose of mtd_blkdevs.c. You
87 should not use them for _anything_ else */
88 DEFINE_MUTEX(mtd_table_mutex);
89 EXPORT_SYMBOL_GPL(mtd_table_mutex);
91 struct mtd_info *__mtd_next_device(int i)
93 return idr_get_next(&mtd_idr, &i);
95 EXPORT_SYMBOL_GPL(__mtd_next_device);
97 static LIST_HEAD(mtd_notifiers);
100 #if defined(CONFIG_MTD_CHAR) || defined(CONFIG_MTD_CHAR_MODULE)
101 #define MTD_DEVT(index) MKDEV(MTD_CHAR_MAJOR, (index)*2)
103 #define MTD_DEVT(index) 0
106 /* REVISIT once MTD uses the driver model better, whoever allocates
107 * the mtd_info will probably want to use the release() hook...
109 static void mtd_release(struct device *dev)
111 struct mtd_info __maybe_unused *mtd = dev_get_drvdata(dev);
112 dev_t index = MTD_DEVT(mtd->index);
114 /* remove /dev/mtdXro node if needed */
116 device_destroy(&mtd_class, index + 1);
119 static int mtd_cls_suspend(struct device *dev, pm_message_t state)
121 struct mtd_info *mtd = dev_get_drvdata(dev);
123 return mtd ? mtd_suspend(mtd) : 0;
126 static int mtd_cls_resume(struct device *dev)
128 struct mtd_info *mtd = dev_get_drvdata(dev);
135 static ssize_t mtd_type_show(struct device *dev,
136 struct device_attribute *attr, char *buf)
138 struct mtd_info *mtd = dev_get_drvdata(dev);
167 return snprintf(buf, PAGE_SIZE, "%s\n", type);
169 static DEVICE_ATTR(type, S_IRUGO, mtd_type_show, NULL);
171 static ssize_t mtd_flags_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, "0x%lx\n", (unsigned long)mtd->flags);
179 static DEVICE_ATTR(flags, S_IRUGO, mtd_flags_show, NULL);
181 static ssize_t mtd_size_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, "%llu\n",
187 (unsigned long long)mtd->size);
190 static DEVICE_ATTR(size, S_IRUGO, mtd_size_show, NULL);
192 static ssize_t mtd_erasesize_show(struct device *dev,
193 struct device_attribute *attr, char *buf)
195 struct mtd_info *mtd = dev_get_drvdata(dev);
197 return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->erasesize);
200 static DEVICE_ATTR(erasesize, S_IRUGO, mtd_erasesize_show, NULL);
202 static ssize_t mtd_writesize_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->writesize);
210 static DEVICE_ATTR(writesize, S_IRUGO, mtd_writesize_show, NULL);
212 static ssize_t mtd_subpagesize_show(struct device *dev,
213 struct device_attribute *attr, char *buf)
215 struct mtd_info *mtd = dev_get_drvdata(dev);
216 unsigned int subpagesize = mtd->writesize >> mtd->subpage_sft;
218 return snprintf(buf, PAGE_SIZE, "%u\n", subpagesize);
221 static DEVICE_ATTR(subpagesize, S_IRUGO, mtd_subpagesize_show, NULL);
223 static ssize_t mtd_oobsize_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, "%lu\n", (unsigned long)mtd->oobsize);
231 static DEVICE_ATTR(oobsize, S_IRUGO, mtd_oobsize_show, NULL);
233 static ssize_t mtd_numeraseregions_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->numeraseregions);
241 static DEVICE_ATTR(numeraseregions, S_IRUGO, mtd_numeraseregions_show,
244 static ssize_t mtd_name_show(struct device *dev,
245 struct device_attribute *attr, char *buf)
247 struct mtd_info *mtd = dev_get_drvdata(dev);
249 return snprintf(buf, PAGE_SIZE, "%s\n", mtd->name);
252 static DEVICE_ATTR(name, S_IRUGO, mtd_name_show, NULL);
254 static ssize_t mtd_ecc_strength_show(struct device *dev,
255 struct device_attribute *attr, char *buf)
257 struct mtd_info *mtd = dev_get_drvdata(dev);
259 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->ecc_strength);
261 static DEVICE_ATTR(ecc_strength, S_IRUGO, mtd_ecc_strength_show, NULL);
263 static ssize_t mtd_bitflip_threshold_show(struct device *dev,
264 struct device_attribute *attr,
267 struct mtd_info *mtd = dev_get_drvdata(dev);
269 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->bitflip_threshold);
272 static ssize_t mtd_bitflip_threshold_store(struct device *dev,
273 struct device_attribute *attr,
274 const char *buf, size_t count)
276 struct mtd_info *mtd = dev_get_drvdata(dev);
277 unsigned int bitflip_threshold;
280 retval = kstrtouint(buf, 0, &bitflip_threshold);
284 mtd->bitflip_threshold = bitflip_threshold;
287 static DEVICE_ATTR(bitflip_threshold, S_IRUGO | S_IWUSR,
288 mtd_bitflip_threshold_show,
289 mtd_bitflip_threshold_store);
291 static struct attribute *mtd_attrs[] = {
293 &dev_attr_flags.attr,
295 &dev_attr_erasesize.attr,
296 &dev_attr_writesize.attr,
297 &dev_attr_subpagesize.attr,
298 &dev_attr_oobsize.attr,
299 &dev_attr_numeraseregions.attr,
301 &dev_attr_ecc_strength.attr,
302 &dev_attr_bitflip_threshold.attr,
306 static struct attribute_group mtd_group = {
310 static const struct attribute_group *mtd_groups[] = {
315 static struct device_type mtd_devtype = {
317 .groups = mtd_groups,
318 .release = mtd_release,
322 * add_mtd_device - register an MTD device
323 * @mtd: pointer to new MTD device info structure
325 * Add a device to the list of MTD devices present in the system, and
326 * notify each currently active MTD 'user' of its arrival. Returns
327 * zero on success or 1 on failure, which currently will only happen
328 * if there is insufficient memory or a sysfs error.
331 int add_mtd_device(struct mtd_info *mtd)
333 struct mtd_notifier *not;
336 if (!mtd->backing_dev_info) {
339 mtd->backing_dev_info = &mtd_bdi_rw_mappable;
342 mtd->backing_dev_info = &mtd_bdi_ro_mappable;
345 mtd->backing_dev_info = &mtd_bdi_unmappable;
350 BUG_ON(mtd->writesize == 0);
351 mutex_lock(&mtd_table_mutex);
353 i = idr_alloc(&mtd_idr, mtd, 0, 0, GFP_KERNEL);
360 /* default value if not set by driver */
361 if (mtd->bitflip_threshold == 0)
362 mtd->bitflip_threshold = mtd->ecc_strength;
364 if (is_power_of_2(mtd->erasesize))
365 mtd->erasesize_shift = ffs(mtd->erasesize) - 1;
367 mtd->erasesize_shift = 0;
369 if (is_power_of_2(mtd->writesize))
370 mtd->writesize_shift = ffs(mtd->writesize) - 1;
372 mtd->writesize_shift = 0;
374 mtd->erasesize_mask = (1 << mtd->erasesize_shift) - 1;
375 mtd->writesize_mask = (1 << mtd->writesize_shift) - 1;
377 /* Some chips always power up locked. Unlock them now */
378 if ((mtd->flags & MTD_WRITEABLE) && (mtd->flags & MTD_POWERUP_LOCK)) {
379 error = mtd_unlock(mtd, 0, mtd->size);
380 if (error && error != -EOPNOTSUPP)
382 "%s: unlock failed, writes may not work\n",
386 /* Caller should have set dev.parent to match the
389 mtd->dev.type = &mtd_devtype;
390 mtd->dev.class = &mtd_class;
391 mtd->dev.devt = MTD_DEVT(i);
392 dev_set_name(&mtd->dev, "mtd%d", i);
393 dev_set_drvdata(&mtd->dev, mtd);
394 if (device_register(&mtd->dev) != 0)
398 device_create(&mtd_class, mtd->dev.parent,
402 pr_debug("mtd: Giving out device %d to %s\n", i, mtd->name);
403 /* No need to get a refcount on the module containing
404 the notifier, since we hold the mtd_table_mutex */
405 list_for_each_entry(not, &mtd_notifiers, list)
408 mutex_unlock(&mtd_table_mutex);
409 /* We _know_ we aren't being removed, because
410 our caller is still holding us here. So none
411 of this try_ nonsense, and no bitching about it
413 __module_get(THIS_MODULE);
417 idr_remove(&mtd_idr, i);
419 mutex_unlock(&mtd_table_mutex);
424 * del_mtd_device - unregister an MTD device
425 * @mtd: pointer to MTD device info structure
427 * Remove a device from the list of MTD devices present in the system,
428 * and notify each currently active MTD 'user' of its departure.
429 * Returns zero on success or 1 on failure, which currently will happen
430 * if the requested device does not appear to be present in the list.
433 int del_mtd_device(struct mtd_info *mtd)
436 struct mtd_notifier *not;
438 mutex_lock(&mtd_table_mutex);
440 if (idr_find(&mtd_idr, mtd->index) != mtd) {
445 /* No need to get a refcount on the module containing
446 the notifier, since we hold the mtd_table_mutex */
447 list_for_each_entry(not, &mtd_notifiers, list)
451 printk(KERN_NOTICE "Removing MTD device #%d (%s) with use count %d\n",
452 mtd->index, mtd->name, mtd->usecount);
455 device_unregister(&mtd->dev);
457 idr_remove(&mtd_idr, mtd->index);
459 module_put(THIS_MODULE);
464 mutex_unlock(&mtd_table_mutex);
469 * mtd_device_parse_register - parse partitions and register an MTD device.
471 * @mtd: the MTD device to register
472 * @types: the list of MTD partition probes to try, see
473 * 'parse_mtd_partitions()' for more information
474 * @parser_data: MTD partition parser-specific data
475 * @parts: fallback partition information to register, if parsing fails;
476 * only valid if %nr_parts > %0
477 * @nr_parts: the number of partitions in parts, if zero then the full
478 * MTD device is registered if no partition info is found
480 * This function aggregates MTD partitions parsing (done by
481 * 'parse_mtd_partitions()') and MTD device and partitions registering. It
482 * basically follows the most common pattern found in many MTD drivers:
484 * * It first tries to probe partitions on MTD device @mtd using parsers
485 * specified in @types (if @types is %NULL, then the default list of parsers
486 * is used, see 'parse_mtd_partitions()' for more information). If none are
487 * found this functions tries to fallback to information specified in
489 * * If any partitioning info was found, this function registers the found
491 * * If no partitions were found this function just registers the MTD device
494 * Returns zero in case of success and a negative error code in case of failure.
496 int mtd_device_parse_register(struct mtd_info *mtd, const char **types,
497 struct mtd_part_parser_data *parser_data,
498 const struct mtd_partition *parts,
502 struct mtd_partition *real_parts;
504 err = parse_mtd_partitions(mtd, types, &real_parts, parser_data);
505 if (err <= 0 && nr_parts && parts) {
506 real_parts = kmemdup(parts, sizeof(*parts) * nr_parts,
515 err = add_mtd_partitions(mtd, real_parts, err);
517 } else if (err == 0) {
518 err = add_mtd_device(mtd);
525 EXPORT_SYMBOL_GPL(mtd_device_parse_register);
528 * mtd_device_unregister - unregister an existing MTD device.
530 * @master: the MTD device to unregister. This will unregister both the master
531 * and any partitions if registered.
533 int mtd_device_unregister(struct mtd_info *master)
537 err = del_mtd_partitions(master);
541 if (!device_is_registered(&master->dev))
544 return del_mtd_device(master);
546 EXPORT_SYMBOL_GPL(mtd_device_unregister);
549 * register_mtd_user - register a 'user' of MTD devices.
550 * @new: pointer to notifier info structure
552 * Registers a pair of callbacks function to be called upon addition
553 * or removal of MTD devices. Causes the 'add' callback to be immediately
554 * invoked for each MTD device currently present in the system.
556 void register_mtd_user (struct mtd_notifier *new)
558 struct mtd_info *mtd;
560 mutex_lock(&mtd_table_mutex);
562 list_add(&new->list, &mtd_notifiers);
564 __module_get(THIS_MODULE);
566 mtd_for_each_device(mtd)
569 mutex_unlock(&mtd_table_mutex);
571 EXPORT_SYMBOL_GPL(register_mtd_user);
574 * unregister_mtd_user - unregister a 'user' of MTD devices.
575 * @old: pointer to notifier info structure
577 * Removes a callback function pair from the list of 'users' to be
578 * notified upon addition or removal of MTD devices. Causes the
579 * 'remove' callback to be immediately invoked for each MTD device
580 * currently present in the system.
582 int unregister_mtd_user (struct mtd_notifier *old)
584 struct mtd_info *mtd;
586 mutex_lock(&mtd_table_mutex);
588 module_put(THIS_MODULE);
590 mtd_for_each_device(mtd)
593 list_del(&old->list);
594 mutex_unlock(&mtd_table_mutex);
597 EXPORT_SYMBOL_GPL(unregister_mtd_user);
600 * get_mtd_device - obtain a validated handle for an MTD device
601 * @mtd: last known address of the required MTD device
602 * @num: internal device number of the required MTD device
604 * Given a number and NULL address, return the num'th entry in the device
605 * table, if any. Given an address and num == -1, search the device table
606 * for a device with that address and return if it's still present. Given
607 * both, return the num'th driver only if its address matches. Return
610 struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num)
612 struct mtd_info *ret = NULL, *other;
615 mutex_lock(&mtd_table_mutex);
618 mtd_for_each_device(other) {
624 } else if (num >= 0) {
625 ret = idr_find(&mtd_idr, num);
626 if (mtd && mtd != ret)
635 err = __get_mtd_device(ret);
639 mutex_unlock(&mtd_table_mutex);
642 EXPORT_SYMBOL_GPL(get_mtd_device);
645 int __get_mtd_device(struct mtd_info *mtd)
649 if (!try_module_get(mtd->owner))
652 if (mtd->_get_device) {
653 err = mtd->_get_device(mtd);
656 module_put(mtd->owner);
663 EXPORT_SYMBOL_GPL(__get_mtd_device);
666 * get_mtd_device_nm - obtain a validated handle for an MTD device by
668 * @name: MTD device name to open
670 * This function returns MTD device description structure in case of
671 * success and an error code in case of failure.
673 struct mtd_info *get_mtd_device_nm(const char *name)
676 struct mtd_info *mtd = NULL, *other;
678 mutex_lock(&mtd_table_mutex);
680 mtd_for_each_device(other) {
681 if (!strcmp(name, other->name)) {
690 err = __get_mtd_device(mtd);
694 mutex_unlock(&mtd_table_mutex);
698 mutex_unlock(&mtd_table_mutex);
701 EXPORT_SYMBOL_GPL(get_mtd_device_nm);
703 void put_mtd_device(struct mtd_info *mtd)
705 mutex_lock(&mtd_table_mutex);
706 __put_mtd_device(mtd);
707 mutex_unlock(&mtd_table_mutex);
710 EXPORT_SYMBOL_GPL(put_mtd_device);
712 void __put_mtd_device(struct mtd_info *mtd)
715 BUG_ON(mtd->usecount < 0);
717 if (mtd->_put_device)
718 mtd->_put_device(mtd);
720 module_put(mtd->owner);
722 EXPORT_SYMBOL_GPL(__put_mtd_device);
725 * Erase is an asynchronous operation. Device drivers are supposed
726 * to call instr->callback() whenever the operation completes, even
727 * if it completes with a failure.
728 * Callers are supposed to pass a callback function and wait for it
729 * to be called before writing to the block.
731 int mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
733 if (instr->addr > mtd->size || instr->len > mtd->size - instr->addr)
735 if (!(mtd->flags & MTD_WRITEABLE))
737 instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
739 instr->state = MTD_ERASE_DONE;
740 mtd_erase_callback(instr);
743 return mtd->_erase(mtd, instr);
745 EXPORT_SYMBOL_GPL(mtd_erase);
748 * This stuff for eXecute-In-Place. phys is optional and may be set to NULL.
750 int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
751 void **virt, resource_size_t *phys)
759 if (from < 0 || from > mtd->size || len > mtd->size - from)
763 return mtd->_point(mtd, from, len, retlen, virt, phys);
765 EXPORT_SYMBOL_GPL(mtd_point);
767 /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
768 int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
772 if (from < 0 || from > mtd->size || len > mtd->size - from)
776 return mtd->_unpoint(mtd, from, len);
778 EXPORT_SYMBOL_GPL(mtd_unpoint);
781 * Allow NOMMU mmap() to directly map the device (if not NULL)
782 * - return the address to which the offset maps
783 * - return -ENOSYS to indicate refusal to do the mapping
785 unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
786 unsigned long offset, unsigned long flags)
788 if (!mtd->_get_unmapped_area)
790 if (offset > mtd->size || len > mtd->size - offset)
792 return mtd->_get_unmapped_area(mtd, len, offset, flags);
794 EXPORT_SYMBOL_GPL(mtd_get_unmapped_area);
796 int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
801 if (from < 0 || from > mtd->size || len > mtd->size - from)
807 * In the absence of an error, drivers return a non-negative integer
808 * representing the maximum number of bitflips that were corrected on
809 * any one ecc region (if applicable; zero otherwise).
811 ret_code = mtd->_read(mtd, from, len, retlen, buf);
812 if (unlikely(ret_code < 0))
814 if (mtd->ecc_strength == 0)
815 return 0; /* device lacks ecc */
816 return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
818 EXPORT_SYMBOL_GPL(mtd_read);
820 int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
824 if (to < 0 || to > mtd->size || len > mtd->size - to)
826 if (!mtd->_write || !(mtd->flags & MTD_WRITEABLE))
830 return mtd->_write(mtd, to, len, retlen, buf);
832 EXPORT_SYMBOL_GPL(mtd_write);
835 * In blackbox flight recorder like scenarios we want to make successful writes
836 * in interrupt context. panic_write() is only intended to be called when its
837 * known the kernel is about to panic and we need the write to succeed. Since
838 * the kernel is not going to be running for much longer, this function can
839 * break locks and delay to ensure the write succeeds (but not sleep).
841 int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
845 if (!mtd->_panic_write)
847 if (to < 0 || to > mtd->size || len > mtd->size - to)
849 if (!(mtd->flags & MTD_WRITEABLE))
853 return mtd->_panic_write(mtd, to, len, retlen, buf);
855 EXPORT_SYMBOL_GPL(mtd_panic_write);
857 int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops)
860 ops->retlen = ops->oobretlen = 0;
864 * In cases where ops->datbuf != NULL, mtd->_read_oob() has semantics
865 * similar to mtd->_read(), returning a non-negative integer
866 * representing max bitflips. In other cases, mtd->_read_oob() may
867 * return -EUCLEAN. In all cases, perform similar logic to mtd_read().
869 ret_code = mtd->_read_oob(mtd, from, ops);
870 if (unlikely(ret_code < 0))
872 if (mtd->ecc_strength == 0)
873 return 0; /* device lacks ecc */
874 return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
876 EXPORT_SYMBOL_GPL(mtd_read_oob);
879 * Method to access the protection register area, present in some flash
880 * devices. The user data is one time programmable but the factory data is read
883 int mtd_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
886 if (!mtd->_get_fact_prot_info)
890 return mtd->_get_fact_prot_info(mtd, buf, len);
892 EXPORT_SYMBOL_GPL(mtd_get_fact_prot_info);
894 int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
895 size_t *retlen, u_char *buf)
898 if (!mtd->_read_fact_prot_reg)
902 return mtd->_read_fact_prot_reg(mtd, from, len, retlen, buf);
904 EXPORT_SYMBOL_GPL(mtd_read_fact_prot_reg);
906 int mtd_get_user_prot_info(struct mtd_info *mtd, struct otp_info *buf,
909 if (!mtd->_get_user_prot_info)
913 return mtd->_get_user_prot_info(mtd, buf, len);
915 EXPORT_SYMBOL_GPL(mtd_get_user_prot_info);
917 int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
918 size_t *retlen, u_char *buf)
921 if (!mtd->_read_user_prot_reg)
925 return mtd->_read_user_prot_reg(mtd, from, len, retlen, buf);
927 EXPORT_SYMBOL_GPL(mtd_read_user_prot_reg);
929 int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
930 size_t *retlen, u_char *buf)
933 if (!mtd->_write_user_prot_reg)
937 return mtd->_write_user_prot_reg(mtd, to, len, retlen, buf);
939 EXPORT_SYMBOL_GPL(mtd_write_user_prot_reg);
941 int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len)
943 if (!mtd->_lock_user_prot_reg)
947 return mtd->_lock_user_prot_reg(mtd, from, len);
949 EXPORT_SYMBOL_GPL(mtd_lock_user_prot_reg);
951 /* Chip-supported device locking */
952 int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
956 if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
960 return mtd->_lock(mtd, ofs, len);
962 EXPORT_SYMBOL_GPL(mtd_lock);
964 int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
968 if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
972 return mtd->_unlock(mtd, ofs, len);
974 EXPORT_SYMBOL_GPL(mtd_unlock);
976 int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
978 if (!mtd->_is_locked)
980 if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
984 return mtd->_is_locked(mtd, ofs, len);
986 EXPORT_SYMBOL_GPL(mtd_is_locked);
988 int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs)
990 if (!mtd->_block_isbad)
992 if (ofs < 0 || ofs > mtd->size)
994 return mtd->_block_isbad(mtd, ofs);
996 EXPORT_SYMBOL_GPL(mtd_block_isbad);
998 int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs)
1000 if (!mtd->_block_markbad)
1002 if (ofs < 0 || ofs > mtd->size)
1004 if (!(mtd->flags & MTD_WRITEABLE))
1006 return mtd->_block_markbad(mtd, ofs);
1008 EXPORT_SYMBOL_GPL(mtd_block_markbad);
1011 * default_mtd_writev - the default writev method
1012 * @mtd: mtd device description object pointer
1013 * @vecs: the vectors to write
1014 * @count: count of vectors in @vecs
1015 * @to: the MTD device offset to write to
1016 * @retlen: on exit contains the count of bytes written to the MTD device.
1018 * This function returns zero in case of success and a negative error code in
1021 static int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
1022 unsigned long count, loff_t to, size_t *retlen)
1025 size_t totlen = 0, thislen;
1028 for (i = 0; i < count; i++) {
1029 if (!vecs[i].iov_len)
1031 ret = mtd_write(mtd, to, vecs[i].iov_len, &thislen,
1034 if (ret || thislen != vecs[i].iov_len)
1036 to += vecs[i].iov_len;
1043 * mtd_writev - the vector-based MTD write method
1044 * @mtd: mtd device description object pointer
1045 * @vecs: the vectors to write
1046 * @count: count of vectors in @vecs
1047 * @to: the MTD device offset to write to
1048 * @retlen: on exit contains the count of bytes written to the MTD device.
1050 * This function returns zero in case of success and a negative error code in
1053 int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
1054 unsigned long count, loff_t to, size_t *retlen)
1057 if (!(mtd->flags & MTD_WRITEABLE))
1060 return default_mtd_writev(mtd, vecs, count, to, retlen);
1061 return mtd->_writev(mtd, vecs, count, to, retlen);
1063 EXPORT_SYMBOL_GPL(mtd_writev);
1066 * mtd_kmalloc_up_to - allocate a contiguous buffer up to the specified size
1067 * @mtd: mtd device description object pointer
1068 * @size: a pointer to the ideal or maximum size of the allocation, points
1069 * to the actual allocation size on success.
1071 * This routine attempts to allocate a contiguous kernel buffer up to
1072 * the specified size, backing off the size of the request exponentially
1073 * until the request succeeds or until the allocation size falls below
1074 * the system page size. This attempts to make sure it does not adversely
1075 * impact system performance, so when allocating more than one page, we
1076 * ask the memory allocator to avoid re-trying, swapping, writing back
1077 * or performing I/O.
1079 * Note, this function also makes sure that the allocated buffer is aligned to
1080 * the MTD device's min. I/O unit, i.e. the "mtd->writesize" value.
1082 * This is called, for example by mtd_{read,write} and jffs2_scan_medium,
1083 * to handle smaller (i.e. degraded) buffer allocations under low- or
1084 * fragmented-memory situations where such reduced allocations, from a
1085 * requested ideal, are allowed.
1087 * Returns a pointer to the allocated buffer on success; otherwise, NULL.
1089 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size)
1091 gfp_t flags = __GFP_NOWARN | __GFP_WAIT |
1092 __GFP_NORETRY | __GFP_NO_KSWAPD;
1093 size_t min_alloc = max_t(size_t, mtd->writesize, PAGE_SIZE);
1096 *size = min_t(size_t, *size, KMALLOC_MAX_SIZE);
1098 while (*size > min_alloc) {
1099 kbuf = kmalloc(*size, flags);
1104 *size = ALIGN(*size, mtd->writesize);
1108 * For the last resort allocation allow 'kmalloc()' to do all sorts of
1109 * things (write-back, dropping caches, etc) by using GFP_KERNEL.
1111 return kmalloc(*size, GFP_KERNEL);
1113 EXPORT_SYMBOL_GPL(mtd_kmalloc_up_to);
1115 #ifdef CONFIG_PROC_FS
1117 /*====================================================================*/
1118 /* Support for /proc/mtd */
1120 static struct proc_dir_entry *proc_mtd;
1122 static int mtd_proc_show(struct seq_file *m, void *v)
1124 struct mtd_info *mtd;
1126 seq_puts(m, "dev: size erasesize name\n");
1127 mutex_lock(&mtd_table_mutex);
1128 mtd_for_each_device(mtd) {
1129 seq_printf(m, "mtd%d: %8.8llx %8.8x \"%s\"\n",
1130 mtd->index, (unsigned long long)mtd->size,
1131 mtd->erasesize, mtd->name);
1133 mutex_unlock(&mtd_table_mutex);
1137 static int mtd_proc_open(struct inode *inode, struct file *file)
1139 return single_open(file, mtd_proc_show, NULL);
1142 static const struct file_operations mtd_proc_ops = {
1143 .open = mtd_proc_open,
1145 .llseek = seq_lseek,
1146 .release = single_release,
1148 #endif /* CONFIG_PROC_FS */
1150 /*====================================================================*/
1153 static int __init mtd_bdi_init(struct backing_dev_info *bdi, const char *name)
1157 ret = bdi_init(bdi);
1159 ret = bdi_register(bdi, NULL, name);
1167 static int __init init_mtd(void)
1171 ret = class_register(&mtd_class);
1175 ret = mtd_bdi_init(&mtd_bdi_unmappable, "mtd-unmap");
1179 ret = mtd_bdi_init(&mtd_bdi_ro_mappable, "mtd-romap");
1183 ret = mtd_bdi_init(&mtd_bdi_rw_mappable, "mtd-rwmap");
1187 #ifdef CONFIG_PROC_FS
1188 proc_mtd = proc_create("mtd", 0, NULL, &mtd_proc_ops);
1189 #endif /* CONFIG_PROC_FS */
1193 bdi_destroy(&mtd_bdi_ro_mappable);
1195 bdi_destroy(&mtd_bdi_unmappable);
1197 class_unregister(&mtd_class);
1199 pr_err("Error registering mtd class or bdi: %d\n", ret);
1203 static void __exit cleanup_mtd(void)
1205 #ifdef CONFIG_PROC_FS
1207 remove_proc_entry( "mtd", NULL);
1208 #endif /* CONFIG_PROC_FS */
1209 class_unregister(&mtd_class);
1210 bdi_destroy(&mtd_bdi_unmappable);
1211 bdi_destroy(&mtd_bdi_ro_mappable);
1212 bdi_destroy(&mtd_bdi_rw_mappable);
1215 module_init(init_mtd);
1216 module_exit(cleanup_mtd);
1218 MODULE_LICENSE("GPL");
1219 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
1220 MODULE_DESCRIPTION("Core MTD registration and access routines");