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>
40 #include <linux/mtd/mtd.h>
41 #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 #define MTD_DEVT(index) MKDEV(MTD_CHAR_MAJOR, (index)*2)
102 /* REVISIT once MTD uses the driver model better, whoever allocates
103 * the mtd_info will probably want to use the release() hook...
105 static void mtd_release(struct device *dev)
107 struct mtd_info __maybe_unused *mtd = dev_get_drvdata(dev);
108 dev_t index = MTD_DEVT(mtd->index);
110 /* remove /dev/mtdXro node if needed */
112 device_destroy(&mtd_class, index + 1);
115 static int mtd_cls_suspend(struct device *dev, pm_message_t state)
117 struct mtd_info *mtd = dev_get_drvdata(dev);
119 return mtd ? mtd_suspend(mtd) : 0;
122 static int mtd_cls_resume(struct device *dev)
124 struct mtd_info *mtd = dev_get_drvdata(dev);
131 static ssize_t mtd_type_show(struct device *dev,
132 struct device_attribute *attr, char *buf)
134 struct mtd_info *mtd = dev_get_drvdata(dev);
163 return snprintf(buf, PAGE_SIZE, "%s\n", type);
165 static DEVICE_ATTR(type, S_IRUGO, mtd_type_show, NULL);
167 static ssize_t mtd_flags_show(struct device *dev,
168 struct device_attribute *attr, char *buf)
170 struct mtd_info *mtd = dev_get_drvdata(dev);
172 return snprintf(buf, PAGE_SIZE, "0x%lx\n", (unsigned long)mtd->flags);
175 static DEVICE_ATTR(flags, S_IRUGO, mtd_flags_show, NULL);
177 static ssize_t mtd_size_show(struct device *dev,
178 struct device_attribute *attr, char *buf)
180 struct mtd_info *mtd = dev_get_drvdata(dev);
182 return snprintf(buf, PAGE_SIZE, "%llu\n",
183 (unsigned long long)mtd->size);
186 static DEVICE_ATTR(size, S_IRUGO, mtd_size_show, NULL);
188 static ssize_t mtd_erasesize_show(struct device *dev,
189 struct device_attribute *attr, char *buf)
191 struct mtd_info *mtd = dev_get_drvdata(dev);
193 return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->erasesize);
196 static DEVICE_ATTR(erasesize, S_IRUGO, mtd_erasesize_show, NULL);
198 static ssize_t mtd_writesize_show(struct device *dev,
199 struct device_attribute *attr, char *buf)
201 struct mtd_info *mtd = dev_get_drvdata(dev);
203 return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->writesize);
206 static DEVICE_ATTR(writesize, S_IRUGO, mtd_writesize_show, NULL);
208 static ssize_t mtd_subpagesize_show(struct device *dev,
209 struct device_attribute *attr, char *buf)
211 struct mtd_info *mtd = dev_get_drvdata(dev);
212 unsigned int subpagesize = mtd->writesize >> mtd->subpage_sft;
214 return snprintf(buf, PAGE_SIZE, "%u\n", subpagesize);
217 static DEVICE_ATTR(subpagesize, S_IRUGO, mtd_subpagesize_show, NULL);
219 static ssize_t mtd_oobsize_show(struct device *dev,
220 struct device_attribute *attr, char *buf)
222 struct mtd_info *mtd = dev_get_drvdata(dev);
224 return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->oobsize);
227 static DEVICE_ATTR(oobsize, S_IRUGO, mtd_oobsize_show, NULL);
229 static ssize_t mtd_numeraseregions_show(struct device *dev,
230 struct device_attribute *attr, char *buf)
232 struct mtd_info *mtd = dev_get_drvdata(dev);
234 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->numeraseregions);
237 static DEVICE_ATTR(numeraseregions, S_IRUGO, mtd_numeraseregions_show,
240 static ssize_t mtd_name_show(struct device *dev,
241 struct device_attribute *attr, char *buf)
243 struct mtd_info *mtd = dev_get_drvdata(dev);
245 return snprintf(buf, PAGE_SIZE, "%s\n", mtd->name);
248 static DEVICE_ATTR(name, S_IRUGO, mtd_name_show, NULL);
250 static ssize_t mtd_ecc_strength_show(struct device *dev,
251 struct device_attribute *attr, char *buf)
253 struct mtd_info *mtd = dev_get_drvdata(dev);
255 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->ecc_strength);
257 static DEVICE_ATTR(ecc_strength, S_IRUGO, mtd_ecc_strength_show, NULL);
259 static ssize_t mtd_bitflip_threshold_show(struct device *dev,
260 struct device_attribute *attr,
263 struct mtd_info *mtd = dev_get_drvdata(dev);
265 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->bitflip_threshold);
268 static ssize_t mtd_bitflip_threshold_store(struct device *dev,
269 struct device_attribute *attr,
270 const char *buf, size_t count)
272 struct mtd_info *mtd = dev_get_drvdata(dev);
273 unsigned int bitflip_threshold;
276 retval = kstrtouint(buf, 0, &bitflip_threshold);
280 mtd->bitflip_threshold = bitflip_threshold;
283 static DEVICE_ATTR(bitflip_threshold, S_IRUGO | S_IWUSR,
284 mtd_bitflip_threshold_show,
285 mtd_bitflip_threshold_store);
287 static struct attribute *mtd_attrs[] = {
289 &dev_attr_flags.attr,
291 &dev_attr_erasesize.attr,
292 &dev_attr_writesize.attr,
293 &dev_attr_subpagesize.attr,
294 &dev_attr_oobsize.attr,
295 &dev_attr_numeraseregions.attr,
297 &dev_attr_ecc_strength.attr,
298 &dev_attr_bitflip_threshold.attr,
302 static struct attribute_group mtd_group = {
306 static const struct attribute_group *mtd_groups[] = {
311 static struct device_type mtd_devtype = {
313 .groups = mtd_groups,
314 .release = mtd_release,
318 * add_mtd_device - register an MTD device
319 * @mtd: pointer to new MTD device info structure
321 * Add a device to the list of MTD devices present in the system, and
322 * notify each currently active MTD 'user' of its arrival. Returns
323 * zero on success or 1 on failure, which currently will only happen
324 * if there is insufficient memory or a sysfs error.
327 int add_mtd_device(struct mtd_info *mtd)
329 struct mtd_notifier *not;
332 if (!mtd->backing_dev_info) {
335 mtd->backing_dev_info = &mtd_bdi_rw_mappable;
338 mtd->backing_dev_info = &mtd_bdi_ro_mappable;
341 mtd->backing_dev_info = &mtd_bdi_unmappable;
346 BUG_ON(mtd->writesize == 0);
347 mutex_lock(&mtd_table_mutex);
349 i = idr_alloc(&mtd_idr, mtd, 0, 0, GFP_KERNEL);
356 /* default value if not set by driver */
357 if (mtd->bitflip_threshold == 0)
358 mtd->bitflip_threshold = mtd->ecc_strength;
360 if (is_power_of_2(mtd->erasesize))
361 mtd->erasesize_shift = ffs(mtd->erasesize) - 1;
363 mtd->erasesize_shift = 0;
365 if (is_power_of_2(mtd->writesize))
366 mtd->writesize_shift = ffs(mtd->writesize) - 1;
368 mtd->writesize_shift = 0;
370 mtd->erasesize_mask = (1 << mtd->erasesize_shift) - 1;
371 mtd->writesize_mask = (1 << mtd->writesize_shift) - 1;
373 /* Some chips always power up locked. Unlock them now */
374 if ((mtd->flags & MTD_WRITEABLE) && (mtd->flags & MTD_POWERUP_LOCK)) {
375 error = mtd_unlock(mtd, 0, mtd->size);
376 if (error && error != -EOPNOTSUPP)
378 "%s: unlock failed, writes may not work\n",
382 /* Caller should have set dev.parent to match the
385 mtd->dev.type = &mtd_devtype;
386 mtd->dev.class = &mtd_class;
387 mtd->dev.devt = MTD_DEVT(i);
388 dev_set_name(&mtd->dev, "mtd%d", i);
389 dev_set_drvdata(&mtd->dev, mtd);
390 if (device_register(&mtd->dev) != 0)
394 device_create(&mtd_class, mtd->dev.parent,
398 pr_debug("mtd: Giving out device %d to %s\n", i, mtd->name);
399 /* No need to get a refcount on the module containing
400 the notifier, since we hold the mtd_table_mutex */
401 list_for_each_entry(not, &mtd_notifiers, list)
404 mutex_unlock(&mtd_table_mutex);
405 /* We _know_ we aren't being removed, because
406 our caller is still holding us here. So none
407 of this try_ nonsense, and no bitching about it
409 __module_get(THIS_MODULE);
413 idr_remove(&mtd_idr, i);
415 mutex_unlock(&mtd_table_mutex);
420 * del_mtd_device - unregister an MTD device
421 * @mtd: pointer to MTD device info structure
423 * Remove a device from the list of MTD devices present in the system,
424 * and notify each currently active MTD 'user' of its departure.
425 * Returns zero on success or 1 on failure, which currently will happen
426 * if the requested device does not appear to be present in the list.
429 int del_mtd_device(struct mtd_info *mtd)
432 struct mtd_notifier *not;
434 mutex_lock(&mtd_table_mutex);
436 if (idr_find(&mtd_idr, mtd->index) != mtd) {
441 /* No need to get a refcount on the module containing
442 the notifier, since we hold the mtd_table_mutex */
443 list_for_each_entry(not, &mtd_notifiers, list)
447 printk(KERN_NOTICE "Removing MTD device #%d (%s) with use count %d\n",
448 mtd->index, mtd->name, mtd->usecount);
451 device_unregister(&mtd->dev);
453 idr_remove(&mtd_idr, mtd->index);
455 module_put(THIS_MODULE);
460 mutex_unlock(&mtd_table_mutex);
465 * mtd_device_parse_register - parse partitions and register an MTD device.
467 * @mtd: the MTD device to register
468 * @types: the list of MTD partition probes to try, see
469 * 'parse_mtd_partitions()' for more information
470 * @parser_data: MTD partition parser-specific data
471 * @parts: fallback partition information to register, if parsing fails;
472 * only valid if %nr_parts > %0
473 * @nr_parts: the number of partitions in parts, if zero then the full
474 * MTD device is registered if no partition info is found
476 * This function aggregates MTD partitions parsing (done by
477 * 'parse_mtd_partitions()') and MTD device and partitions registering. It
478 * basically follows the most common pattern found in many MTD drivers:
480 * * It first tries to probe partitions on MTD device @mtd using parsers
481 * specified in @types (if @types is %NULL, then the default list of parsers
482 * is used, see 'parse_mtd_partitions()' for more information). If none are
483 * found this functions tries to fallback to information specified in
485 * * If any partitioning info was found, this function registers the found
487 * * If no partitions were found this function just registers the MTD device
490 * Returns zero in case of success and a negative error code in case of failure.
492 int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types,
493 struct mtd_part_parser_data *parser_data,
494 const struct mtd_partition *parts,
498 struct mtd_partition *real_parts;
500 err = parse_mtd_partitions(mtd, types, &real_parts, parser_data);
501 if (err <= 0 && nr_parts && parts) {
502 real_parts = kmemdup(parts, sizeof(*parts) * nr_parts,
511 err = add_mtd_partitions(mtd, real_parts, err);
513 } else if (err == 0) {
514 err = add_mtd_device(mtd);
521 EXPORT_SYMBOL_GPL(mtd_device_parse_register);
524 * mtd_device_unregister - unregister an existing MTD device.
526 * @master: the MTD device to unregister. This will unregister both the master
527 * and any partitions if registered.
529 int mtd_device_unregister(struct mtd_info *master)
533 err = del_mtd_partitions(master);
537 if (!device_is_registered(&master->dev))
540 return del_mtd_device(master);
542 EXPORT_SYMBOL_GPL(mtd_device_unregister);
545 * register_mtd_user - register a 'user' of MTD devices.
546 * @new: pointer to notifier info structure
548 * Registers a pair of callbacks function to be called upon addition
549 * or removal of MTD devices. Causes the 'add' callback to be immediately
550 * invoked for each MTD device currently present in the system.
552 void register_mtd_user (struct mtd_notifier *new)
554 struct mtd_info *mtd;
556 mutex_lock(&mtd_table_mutex);
558 list_add(&new->list, &mtd_notifiers);
560 __module_get(THIS_MODULE);
562 mtd_for_each_device(mtd)
565 mutex_unlock(&mtd_table_mutex);
567 EXPORT_SYMBOL_GPL(register_mtd_user);
570 * unregister_mtd_user - unregister a 'user' of MTD devices.
571 * @old: pointer to notifier info structure
573 * Removes a callback function pair from the list of 'users' to be
574 * notified upon addition or removal of MTD devices. Causes the
575 * 'remove' callback to be immediately invoked for each MTD device
576 * currently present in the system.
578 int unregister_mtd_user (struct mtd_notifier *old)
580 struct mtd_info *mtd;
582 mutex_lock(&mtd_table_mutex);
584 module_put(THIS_MODULE);
586 mtd_for_each_device(mtd)
589 list_del(&old->list);
590 mutex_unlock(&mtd_table_mutex);
593 EXPORT_SYMBOL_GPL(unregister_mtd_user);
596 * get_mtd_device - obtain a validated handle for an MTD device
597 * @mtd: last known address of the required MTD device
598 * @num: internal device number of the required MTD device
600 * Given a number and NULL address, return the num'th entry in the device
601 * table, if any. Given an address and num == -1, search the device table
602 * for a device with that address and return if it's still present. Given
603 * both, return the num'th driver only if its address matches. Return
606 struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num)
608 struct mtd_info *ret = NULL, *other;
611 mutex_lock(&mtd_table_mutex);
614 mtd_for_each_device(other) {
620 } else if (num >= 0) {
621 ret = idr_find(&mtd_idr, num);
622 if (mtd && mtd != ret)
631 err = __get_mtd_device(ret);
635 mutex_unlock(&mtd_table_mutex);
638 EXPORT_SYMBOL_GPL(get_mtd_device);
641 int __get_mtd_device(struct mtd_info *mtd)
645 if (!try_module_get(mtd->owner))
648 if (mtd->_get_device) {
649 err = mtd->_get_device(mtd);
652 module_put(mtd->owner);
659 EXPORT_SYMBOL_GPL(__get_mtd_device);
662 * get_mtd_device_nm - obtain a validated handle for an MTD device by
664 * @name: MTD device name to open
666 * This function returns MTD device description structure in case of
667 * success and an error code in case of failure.
669 struct mtd_info *get_mtd_device_nm(const char *name)
672 struct mtd_info *mtd = NULL, *other;
674 mutex_lock(&mtd_table_mutex);
676 mtd_for_each_device(other) {
677 if (!strcmp(name, other->name)) {
686 err = __get_mtd_device(mtd);
690 mutex_unlock(&mtd_table_mutex);
694 mutex_unlock(&mtd_table_mutex);
697 EXPORT_SYMBOL_GPL(get_mtd_device_nm);
699 void put_mtd_device(struct mtd_info *mtd)
701 mutex_lock(&mtd_table_mutex);
702 __put_mtd_device(mtd);
703 mutex_unlock(&mtd_table_mutex);
706 EXPORT_SYMBOL_GPL(put_mtd_device);
708 void __put_mtd_device(struct mtd_info *mtd)
711 BUG_ON(mtd->usecount < 0);
713 if (mtd->_put_device)
714 mtd->_put_device(mtd);
716 module_put(mtd->owner);
718 EXPORT_SYMBOL_GPL(__put_mtd_device);
721 * Erase is an asynchronous operation. Device drivers are supposed
722 * to call instr->callback() whenever the operation completes, even
723 * if it completes with a failure.
724 * Callers are supposed to pass a callback function and wait for it
725 * to be called before writing to the block.
727 int mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
729 if (instr->addr > mtd->size || instr->len > mtd->size - instr->addr)
731 if (!(mtd->flags & MTD_WRITEABLE))
733 instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
735 instr->state = MTD_ERASE_DONE;
736 mtd_erase_callback(instr);
739 return mtd->_erase(mtd, instr);
741 EXPORT_SYMBOL_GPL(mtd_erase);
744 * This stuff for eXecute-In-Place. phys is optional and may be set to NULL.
746 int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
747 void **virt, resource_size_t *phys)
755 if (from < 0 || from > mtd->size || len > mtd->size - from)
759 return mtd->_point(mtd, from, len, retlen, virt, phys);
761 EXPORT_SYMBOL_GPL(mtd_point);
763 /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
764 int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
768 if (from < 0 || from > mtd->size || len > mtd->size - from)
772 return mtd->_unpoint(mtd, from, len);
774 EXPORT_SYMBOL_GPL(mtd_unpoint);
777 * Allow NOMMU mmap() to directly map the device (if not NULL)
778 * - return the address to which the offset maps
779 * - return -ENOSYS to indicate refusal to do the mapping
781 unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
782 unsigned long offset, unsigned long flags)
784 if (!mtd->_get_unmapped_area)
786 if (offset > mtd->size || len > mtd->size - offset)
788 return mtd->_get_unmapped_area(mtd, len, offset, flags);
790 EXPORT_SYMBOL_GPL(mtd_get_unmapped_area);
792 int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
797 if (from < 0 || from > mtd->size || len > mtd->size - from)
803 * In the absence of an error, drivers return a non-negative integer
804 * representing the maximum number of bitflips that were corrected on
805 * any one ecc region (if applicable; zero otherwise).
807 ret_code = mtd->_read(mtd, from, len, retlen, buf);
808 if (unlikely(ret_code < 0))
810 if (mtd->ecc_strength == 0)
811 return 0; /* device lacks ecc */
812 return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
814 EXPORT_SYMBOL_GPL(mtd_read);
816 int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
820 if (to < 0 || to > mtd->size || len > mtd->size - to)
822 if (!mtd->_write || !(mtd->flags & MTD_WRITEABLE))
826 return mtd->_write(mtd, to, len, retlen, buf);
828 EXPORT_SYMBOL_GPL(mtd_write);
831 * In blackbox flight recorder like scenarios we want to make successful writes
832 * in interrupt context. panic_write() is only intended to be called when its
833 * known the kernel is about to panic and we need the write to succeed. Since
834 * the kernel is not going to be running for much longer, this function can
835 * break locks and delay to ensure the write succeeds (but not sleep).
837 int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
841 if (!mtd->_panic_write)
843 if (to < 0 || to > mtd->size || len > mtd->size - to)
845 if (!(mtd->flags & MTD_WRITEABLE))
849 return mtd->_panic_write(mtd, to, len, retlen, buf);
851 EXPORT_SYMBOL_GPL(mtd_panic_write);
853 int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops)
856 ops->retlen = ops->oobretlen = 0;
860 * In cases where ops->datbuf != NULL, mtd->_read_oob() has semantics
861 * similar to mtd->_read(), returning a non-negative integer
862 * representing max bitflips. In other cases, mtd->_read_oob() may
863 * return -EUCLEAN. In all cases, perform similar logic to mtd_read().
865 ret_code = mtd->_read_oob(mtd, from, ops);
866 if (unlikely(ret_code < 0))
868 if (mtd->ecc_strength == 0)
869 return 0; /* device lacks ecc */
870 return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
872 EXPORT_SYMBOL_GPL(mtd_read_oob);
875 * Method to access the protection register area, present in some flash
876 * devices. The user data is one time programmable but the factory data is read
879 int mtd_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
882 if (!mtd->_get_fact_prot_info)
886 return mtd->_get_fact_prot_info(mtd, buf, len);
888 EXPORT_SYMBOL_GPL(mtd_get_fact_prot_info);
890 int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
891 size_t *retlen, u_char *buf)
894 if (!mtd->_read_fact_prot_reg)
898 return mtd->_read_fact_prot_reg(mtd, from, len, retlen, buf);
900 EXPORT_SYMBOL_GPL(mtd_read_fact_prot_reg);
902 int mtd_get_user_prot_info(struct mtd_info *mtd, struct otp_info *buf,
905 if (!mtd->_get_user_prot_info)
909 return mtd->_get_user_prot_info(mtd, buf, len);
911 EXPORT_SYMBOL_GPL(mtd_get_user_prot_info);
913 int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
914 size_t *retlen, u_char *buf)
917 if (!mtd->_read_user_prot_reg)
921 return mtd->_read_user_prot_reg(mtd, from, len, retlen, buf);
923 EXPORT_SYMBOL_GPL(mtd_read_user_prot_reg);
925 int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
926 size_t *retlen, u_char *buf)
929 if (!mtd->_write_user_prot_reg)
933 return mtd->_write_user_prot_reg(mtd, to, len, retlen, buf);
935 EXPORT_SYMBOL_GPL(mtd_write_user_prot_reg);
937 int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len)
939 if (!mtd->_lock_user_prot_reg)
943 return mtd->_lock_user_prot_reg(mtd, from, len);
945 EXPORT_SYMBOL_GPL(mtd_lock_user_prot_reg);
947 /* Chip-supported device locking */
948 int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
952 if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
956 return mtd->_lock(mtd, ofs, len);
958 EXPORT_SYMBOL_GPL(mtd_lock);
960 int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
964 if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
968 return mtd->_unlock(mtd, ofs, len);
970 EXPORT_SYMBOL_GPL(mtd_unlock);
972 int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
974 if (!mtd->_is_locked)
976 if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
980 return mtd->_is_locked(mtd, ofs, len);
982 EXPORT_SYMBOL_GPL(mtd_is_locked);
984 int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs)
986 if (!mtd->_block_isbad)
988 if (ofs < 0 || ofs > mtd->size)
990 return mtd->_block_isbad(mtd, ofs);
992 EXPORT_SYMBOL_GPL(mtd_block_isbad);
994 int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs)
996 if (!mtd->_block_markbad)
998 if (ofs < 0 || ofs > mtd->size)
1000 if (!(mtd->flags & MTD_WRITEABLE))
1002 return mtd->_block_markbad(mtd, ofs);
1004 EXPORT_SYMBOL_GPL(mtd_block_markbad);
1007 * default_mtd_writev - the default writev method
1008 * @mtd: mtd device description object pointer
1009 * @vecs: the vectors to write
1010 * @count: count of vectors in @vecs
1011 * @to: the MTD device offset to write to
1012 * @retlen: on exit contains the count of bytes written to the MTD device.
1014 * This function returns zero in case of success and a negative error code in
1017 static int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
1018 unsigned long count, loff_t to, size_t *retlen)
1021 size_t totlen = 0, thislen;
1024 for (i = 0; i < count; i++) {
1025 if (!vecs[i].iov_len)
1027 ret = mtd_write(mtd, to, vecs[i].iov_len, &thislen,
1030 if (ret || thislen != vecs[i].iov_len)
1032 to += vecs[i].iov_len;
1039 * mtd_writev - the vector-based MTD write method
1040 * @mtd: mtd device description object pointer
1041 * @vecs: the vectors to write
1042 * @count: count of vectors in @vecs
1043 * @to: the MTD device offset to write to
1044 * @retlen: on exit contains the count of bytes written to the MTD device.
1046 * This function returns zero in case of success and a negative error code in
1049 int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
1050 unsigned long count, loff_t to, size_t *retlen)
1053 if (!(mtd->flags & MTD_WRITEABLE))
1056 return default_mtd_writev(mtd, vecs, count, to, retlen);
1057 return mtd->_writev(mtd, vecs, count, to, retlen);
1059 EXPORT_SYMBOL_GPL(mtd_writev);
1062 * mtd_kmalloc_up_to - allocate a contiguous buffer up to the specified size
1063 * @mtd: mtd device description object pointer
1064 * @size: a pointer to the ideal or maximum size of the allocation, points
1065 * to the actual allocation size on success.
1067 * This routine attempts to allocate a contiguous kernel buffer up to
1068 * the specified size, backing off the size of the request exponentially
1069 * until the request succeeds or until the allocation size falls below
1070 * the system page size. This attempts to make sure it does not adversely
1071 * impact system performance, so when allocating more than one page, we
1072 * ask the memory allocator to avoid re-trying, swapping, writing back
1073 * or performing I/O.
1075 * Note, this function also makes sure that the allocated buffer is aligned to
1076 * the MTD device's min. I/O unit, i.e. the "mtd->writesize" value.
1078 * This is called, for example by mtd_{read,write} and jffs2_scan_medium,
1079 * to handle smaller (i.e. degraded) buffer allocations under low- or
1080 * fragmented-memory situations where such reduced allocations, from a
1081 * requested ideal, are allowed.
1083 * Returns a pointer to the allocated buffer on success; otherwise, NULL.
1085 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size)
1087 gfp_t flags = __GFP_NOWARN | __GFP_WAIT |
1088 __GFP_NORETRY | __GFP_NO_KSWAPD;
1089 size_t min_alloc = max_t(size_t, mtd->writesize, PAGE_SIZE);
1092 *size = min_t(size_t, *size, KMALLOC_MAX_SIZE);
1094 while (*size > min_alloc) {
1095 kbuf = kmalloc(*size, flags);
1100 *size = ALIGN(*size, mtd->writesize);
1104 * For the last resort allocation allow 'kmalloc()' to do all sorts of
1105 * things (write-back, dropping caches, etc) by using GFP_KERNEL.
1107 return kmalloc(*size, GFP_KERNEL);
1109 EXPORT_SYMBOL_GPL(mtd_kmalloc_up_to);
1111 #ifdef CONFIG_PROC_FS
1113 /*====================================================================*/
1114 /* Support for /proc/mtd */
1116 static int mtd_proc_show(struct seq_file *m, void *v)
1118 struct mtd_info *mtd;
1120 seq_puts(m, "dev: size erasesize name\n");
1121 mutex_lock(&mtd_table_mutex);
1122 mtd_for_each_device(mtd) {
1123 seq_printf(m, "mtd%d: %8.8llx %8.8x \"%s\"\n",
1124 mtd->index, (unsigned long long)mtd->size,
1125 mtd->erasesize, mtd->name);
1127 mutex_unlock(&mtd_table_mutex);
1131 static int mtd_proc_open(struct inode *inode, struct file *file)
1133 return single_open(file, mtd_proc_show, NULL);
1136 static const struct file_operations mtd_proc_ops = {
1137 .open = mtd_proc_open,
1139 .llseek = seq_lseek,
1140 .release = single_release,
1142 #endif /* CONFIG_PROC_FS */
1144 /*====================================================================*/
1147 static int __init mtd_bdi_init(struct backing_dev_info *bdi, const char *name)
1151 ret = bdi_init(bdi);
1153 ret = bdi_register(bdi, NULL, name);
1161 static struct proc_dir_entry *proc_mtd;
1163 static int __init init_mtd(void)
1167 ret = class_register(&mtd_class);
1171 ret = mtd_bdi_init(&mtd_bdi_unmappable, "mtd-unmap");
1175 ret = mtd_bdi_init(&mtd_bdi_ro_mappable, "mtd-romap");
1179 ret = mtd_bdi_init(&mtd_bdi_rw_mappable, "mtd-rwmap");
1183 proc_mtd = proc_create("mtd", 0, NULL, &mtd_proc_ops);
1185 ret = init_mtdchar();
1193 remove_proc_entry("mtd", NULL);
1195 bdi_destroy(&mtd_bdi_ro_mappable);
1197 bdi_destroy(&mtd_bdi_unmappable);
1199 class_unregister(&mtd_class);
1201 pr_err("Error registering mtd class or bdi: %d\n", ret);
1205 static void __exit cleanup_mtd(void)
1209 remove_proc_entry("mtd", NULL);
1210 class_unregister(&mtd_class);
1211 bdi_destroy(&mtd_bdi_unmappable);
1212 bdi_destroy(&mtd_bdi_ro_mappable);
1213 bdi_destroy(&mtd_bdi_rw_mappable);
1216 module_init(init_mtd);
1217 module_exit(cleanup_mtd);
1219 MODULE_LICENSE("GPL");
1220 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
1221 MODULE_DESCRIPTION("Core MTD registration and access routines");