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Commit | Line | Data |
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1da177e4 | 1 | /* |
1da177e4 LT |
2 | * Core registration and callback routines for MTD |
3 | * drivers and users. | |
4 | * | |
a1452a37 DW |
5 | * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org> |
6 | * Copyright © 2006 Red Hat UK Limited | |
7 | * | |
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. | |
12 | * | |
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. | |
17 | * | |
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 | |
21 | * | |
1da177e4 LT |
22 | */ |
23 | ||
1da177e4 LT |
24 | #include <linux/module.h> |
25 | #include <linux/kernel.h> | |
1da177e4 | 26 | #include <linux/ptrace.h> |
447d9bd8 | 27 | #include <linux/seq_file.h> |
1da177e4 LT |
28 | #include <linux/string.h> |
29 | #include <linux/timer.h> | |
30 | #include <linux/major.h> | |
31 | #include <linux/fs.h> | |
7799308f | 32 | #include <linux/err.h> |
1da177e4 LT |
33 | #include <linux/ioctl.h> |
34 | #include <linux/init.h> | |
1da177e4 | 35 | #include <linux/proc_fs.h> |
b520e412 | 36 | #include <linux/idr.h> |
a33eb6b9 | 37 | #include <linux/backing-dev.h> |
05d71b46 | 38 | #include <linux/gfp.h> |
1da177e4 LT |
39 | |
40 | #include <linux/mtd/mtd.h> | |
f5671ab3 | 41 | #include <linux/mtd/partitions.h> |
1da177e4 | 42 | |
356d70f1 | 43 | #include "mtdcore.h" |
a33eb6b9 JE |
44 | /* |
45 | * backing device capabilities for non-mappable devices (such as NAND flash) | |
46 | * - permits private mappings, copies are taken of the data | |
47 | */ | |
ca91facf | 48 | static struct backing_dev_info mtd_bdi_unmappable = { |
a33eb6b9 JE |
49 | .capabilities = BDI_CAP_MAP_COPY, |
50 | }; | |
51 | ||
52 | /* | |
53 | * backing device capabilities for R/O mappable devices (such as ROM) | |
54 | * - permits private mappings, copies are taken of the data | |
55 | * - permits non-writable shared mappings | |
56 | */ | |
ca91facf | 57 | static struct backing_dev_info mtd_bdi_ro_mappable = { |
a33eb6b9 JE |
58 | .capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT | |
59 | BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP), | |
60 | }; | |
61 | ||
62 | /* | |
63 | * backing device capabilities for writable mappable devices (such as RAM) | |
64 | * - permits private mappings, copies are taken of the data | |
65 | * - permits non-writable shared mappings | |
66 | */ | |
ca91facf | 67 | static struct backing_dev_info mtd_bdi_rw_mappable = { |
a33eb6b9 JE |
68 | .capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT | |
69 | BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP | | |
70 | BDI_CAP_WRITE_MAP), | |
71 | }; | |
356d70f1 | 72 | |
15bce40c DW |
73 | static int mtd_cls_suspend(struct device *dev, pm_message_t state); |
74 | static int mtd_cls_resume(struct device *dev); | |
75 | ||
76 | static struct class mtd_class = { | |
77 | .name = "mtd", | |
78 | .owner = THIS_MODULE, | |
79 | .suspend = mtd_cls_suspend, | |
80 | .resume = mtd_cls_resume, | |
81 | }; | |
1f24b5a8 | 82 | |
b520e412 BH |
83 | static DEFINE_IDR(mtd_idr); |
84 | ||
97894cda | 85 | /* These are exported solely for the purpose of mtd_blkdevs.c. You |
1da177e4 | 86 | should not use them for _anything_ else */ |
48b19268 | 87 | DEFINE_MUTEX(mtd_table_mutex); |
1da177e4 | 88 | EXPORT_SYMBOL_GPL(mtd_table_mutex); |
b520e412 BH |
89 | |
90 | struct mtd_info *__mtd_next_device(int i) | |
91 | { | |
92 | return idr_get_next(&mtd_idr, &i); | |
93 | } | |
94 | EXPORT_SYMBOL_GPL(__mtd_next_device); | |
1da177e4 LT |
95 | |
96 | static LIST_HEAD(mtd_notifiers); | |
97 | ||
1f24b5a8 DB |
98 | |
99 | #if defined(CONFIG_MTD_CHAR) || defined(CONFIG_MTD_CHAR_MODULE) | |
100 | #define MTD_DEVT(index) MKDEV(MTD_CHAR_MAJOR, (index)*2) | |
101 | #else | |
102 | #define MTD_DEVT(index) 0 | |
103 | #endif | |
104 | ||
105 | /* REVISIT once MTD uses the driver model better, whoever allocates | |
106 | * the mtd_info will probably want to use the release() hook... | |
107 | */ | |
108 | static void mtd_release(struct device *dev) | |
109 | { | |
2fdb1144 | 110 | dev_t index = MTD_DEVT(dev_to_mtd(dev)->index); |
1f24b5a8 DB |
111 | |
112 | /* remove /dev/mtdXro node if needed */ | |
2fdb1144 | 113 | if (index) |
15bce40c DW |
114 | device_destroy(&mtd_class, index + 1); |
115 | } | |
116 | ||
117 | static int mtd_cls_suspend(struct device *dev, pm_message_t state) | |
118 | { | |
119 | struct mtd_info *mtd = dev_to_mtd(dev); | |
6afc4fdb SB |
120 | |
121 | if (mtd && mtd->suspend) | |
15bce40c DW |
122 | return mtd->suspend(mtd); |
123 | else | |
124 | return 0; | |
125 | } | |
126 | ||
127 | static int mtd_cls_resume(struct device *dev) | |
128 | { | |
129 | struct mtd_info *mtd = dev_to_mtd(dev); | |
130 | ||
6afc4fdb | 131 | if (mtd && mtd->resume) |
15bce40c DW |
132 | mtd->resume(mtd); |
133 | return 0; | |
1f24b5a8 DB |
134 | } |
135 | ||
136 | static ssize_t mtd_type_show(struct device *dev, | |
137 | struct device_attribute *attr, char *buf) | |
138 | { | |
139 | struct mtd_info *mtd = dev_to_mtd(dev); | |
140 | char *type; | |
141 | ||
142 | switch (mtd->type) { | |
143 | case MTD_ABSENT: | |
144 | type = "absent"; | |
145 | break; | |
146 | case MTD_RAM: | |
147 | type = "ram"; | |
148 | break; | |
149 | case MTD_ROM: | |
150 | type = "rom"; | |
151 | break; | |
152 | case MTD_NORFLASH: | |
153 | type = "nor"; | |
154 | break; | |
155 | case MTD_NANDFLASH: | |
156 | type = "nand"; | |
157 | break; | |
158 | case MTD_DATAFLASH: | |
159 | type = "dataflash"; | |
160 | break; | |
161 | case MTD_UBIVOLUME: | |
162 | type = "ubi"; | |
163 | break; | |
164 | default: | |
165 | type = "unknown"; | |
166 | } | |
167 | ||
168 | return snprintf(buf, PAGE_SIZE, "%s\n", type); | |
169 | } | |
694bb7fc KC |
170 | static DEVICE_ATTR(type, S_IRUGO, mtd_type_show, NULL); |
171 | ||
172 | static ssize_t mtd_flags_show(struct device *dev, | |
173 | struct device_attribute *attr, char *buf) | |
174 | { | |
175 | struct mtd_info *mtd = dev_to_mtd(dev); | |
176 | ||
177 | return snprintf(buf, PAGE_SIZE, "0x%lx\n", (unsigned long)mtd->flags); | |
178 | ||
179 | } | |
180 | static DEVICE_ATTR(flags, S_IRUGO, mtd_flags_show, NULL); | |
181 | ||
182 | static ssize_t mtd_size_show(struct device *dev, | |
183 | struct device_attribute *attr, char *buf) | |
184 | { | |
185 | struct mtd_info *mtd = dev_to_mtd(dev); | |
186 | ||
187 | return snprintf(buf, PAGE_SIZE, "%llu\n", | |
188 | (unsigned long long)mtd->size); | |
189 | ||
190 | } | |
191 | static DEVICE_ATTR(size, S_IRUGO, mtd_size_show, NULL); | |
192 | ||
193 | static ssize_t mtd_erasesize_show(struct device *dev, | |
194 | struct device_attribute *attr, char *buf) | |
195 | { | |
196 | struct mtd_info *mtd = dev_to_mtd(dev); | |
197 | ||
198 | return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->erasesize); | |
199 | ||
200 | } | |
201 | static DEVICE_ATTR(erasesize, S_IRUGO, mtd_erasesize_show, NULL); | |
202 | ||
203 | static ssize_t mtd_writesize_show(struct device *dev, | |
204 | struct device_attribute *attr, char *buf) | |
205 | { | |
206 | struct mtd_info *mtd = dev_to_mtd(dev); | |
207 | ||
208 | return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->writesize); | |
209 | ||
210 | } | |
211 | static DEVICE_ATTR(writesize, S_IRUGO, mtd_writesize_show, NULL); | |
212 | ||
e7693548 AB |
213 | static ssize_t mtd_subpagesize_show(struct device *dev, |
214 | struct device_attribute *attr, char *buf) | |
215 | { | |
216 | struct mtd_info *mtd = dev_to_mtd(dev); | |
217 | unsigned int subpagesize = mtd->writesize >> mtd->subpage_sft; | |
218 | ||
219 | return snprintf(buf, PAGE_SIZE, "%u\n", subpagesize); | |
220 | ||
221 | } | |
222 | static DEVICE_ATTR(subpagesize, S_IRUGO, mtd_subpagesize_show, NULL); | |
223 | ||
694bb7fc KC |
224 | static ssize_t mtd_oobsize_show(struct device *dev, |
225 | struct device_attribute *attr, char *buf) | |
226 | { | |
227 | struct mtd_info *mtd = dev_to_mtd(dev); | |
228 | ||
229 | return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->oobsize); | |
230 | ||
231 | } | |
232 | static DEVICE_ATTR(oobsize, S_IRUGO, mtd_oobsize_show, NULL); | |
233 | ||
234 | static ssize_t mtd_numeraseregions_show(struct device *dev, | |
235 | struct device_attribute *attr, char *buf) | |
236 | { | |
237 | struct mtd_info *mtd = dev_to_mtd(dev); | |
238 | ||
239 | return snprintf(buf, PAGE_SIZE, "%u\n", mtd->numeraseregions); | |
240 | ||
241 | } | |
242 | static DEVICE_ATTR(numeraseregions, S_IRUGO, mtd_numeraseregions_show, | |
243 | NULL); | |
244 | ||
245 | static ssize_t mtd_name_show(struct device *dev, | |
246 | struct device_attribute *attr, char *buf) | |
247 | { | |
248 | struct mtd_info *mtd = dev_to_mtd(dev); | |
249 | ||
250 | return snprintf(buf, PAGE_SIZE, "%s\n", mtd->name); | |
251 | ||
252 | } | |
253 | static DEVICE_ATTR(name, S_IRUGO, mtd_name_show, NULL); | |
1f24b5a8 DB |
254 | |
255 | static struct attribute *mtd_attrs[] = { | |
694bb7fc KC |
256 | &dev_attr_type.attr, |
257 | &dev_attr_flags.attr, | |
258 | &dev_attr_size.attr, | |
259 | &dev_attr_erasesize.attr, | |
260 | &dev_attr_writesize.attr, | |
e7693548 | 261 | &dev_attr_subpagesize.attr, |
694bb7fc KC |
262 | &dev_attr_oobsize.attr, |
263 | &dev_attr_numeraseregions.attr, | |
264 | &dev_attr_name.attr, | |
1f24b5a8 DB |
265 | NULL, |
266 | }; | |
267 | ||
fca91088 | 268 | static struct attribute_group mtd_group = { |
1f24b5a8 DB |
269 | .attrs = mtd_attrs, |
270 | }; | |
271 | ||
6469f540 | 272 | static const struct attribute_group *mtd_groups[] = { |
1f24b5a8 DB |
273 | &mtd_group, |
274 | NULL, | |
275 | }; | |
276 | ||
277 | static struct device_type mtd_devtype = { | |
278 | .name = "mtd", | |
279 | .groups = mtd_groups, | |
280 | .release = mtd_release, | |
281 | }; | |
282 | ||
1da177e4 LT |
283 | /** |
284 | * add_mtd_device - register an MTD device | |
285 | * @mtd: pointer to new MTD device info structure | |
286 | * | |
287 | * Add a device to the list of MTD devices present in the system, and | |
288 | * notify each currently active MTD 'user' of its arrival. Returns | |
289 | * zero on success or 1 on failure, which currently will only happen | |
b520e412 | 290 | * if there is insufficient memory or a sysfs error. |
1da177e4 LT |
291 | */ |
292 | ||
293 | int add_mtd_device(struct mtd_info *mtd) | |
294 | { | |
b520e412 BH |
295 | struct mtd_notifier *not; |
296 | int i, error; | |
1da177e4 | 297 | |
402d3265 DH |
298 | if (!mtd->backing_dev_info) { |
299 | switch (mtd->type) { | |
300 | case MTD_RAM: | |
301 | mtd->backing_dev_info = &mtd_bdi_rw_mappable; | |
302 | break; | |
303 | case MTD_ROM: | |
304 | mtd->backing_dev_info = &mtd_bdi_ro_mappable; | |
305 | break; | |
306 | default: | |
307 | mtd->backing_dev_info = &mtd_bdi_unmappable; | |
308 | break; | |
309 | } | |
310 | } | |
311 | ||
783ed81f | 312 | BUG_ON(mtd->writesize == 0); |
48b19268 | 313 | mutex_lock(&mtd_table_mutex); |
1da177e4 | 314 | |
b520e412 BH |
315 | do { |
316 | if (!idr_pre_get(&mtd_idr, GFP_KERNEL)) | |
317 | goto fail_locked; | |
318 | error = idr_get_new(&mtd_idr, mtd, &i); | |
319 | } while (error == -EAGAIN); | |
187ef152 | 320 | |
b520e412 BH |
321 | if (error) |
322 | goto fail_locked; | |
1f24b5a8 | 323 | |
b520e412 BH |
324 | mtd->index = i; |
325 | mtd->usecount = 0; | |
326 | ||
327 | if (is_power_of_2(mtd->erasesize)) | |
328 | mtd->erasesize_shift = ffs(mtd->erasesize) - 1; | |
329 | else | |
330 | mtd->erasesize_shift = 0; | |
331 | ||
332 | if (is_power_of_2(mtd->writesize)) | |
333 | mtd->writesize_shift = ffs(mtd->writesize) - 1; | |
334 | else | |
335 | mtd->writesize_shift = 0; | |
336 | ||
337 | mtd->erasesize_mask = (1 << mtd->erasesize_shift) - 1; | |
338 | mtd->writesize_mask = (1 << mtd->writesize_shift) - 1; | |
339 | ||
340 | /* Some chips always power up locked. Unlock them now */ | |
341 | if ((mtd->flags & MTD_WRITEABLE) | |
342 | && (mtd->flags & MTD_POWERUP_LOCK) && mtd->unlock) { | |
343 | if (mtd->unlock(mtd, 0, mtd->size)) | |
344 | printk(KERN_WARNING | |
345 | "%s: unlock failed, writes may not work\n", | |
346 | mtd->name); | |
347 | } | |
348 | ||
349 | /* Caller should have set dev.parent to match the | |
350 | * physical device. | |
351 | */ | |
352 | mtd->dev.type = &mtd_devtype; | |
353 | mtd->dev.class = &mtd_class; | |
354 | mtd->dev.devt = MTD_DEVT(i); | |
355 | dev_set_name(&mtd->dev, "mtd%d", i); | |
356 | dev_set_drvdata(&mtd->dev, mtd); | |
357 | if (device_register(&mtd->dev) != 0) | |
358 | goto fail_added; | |
359 | ||
360 | if (MTD_DEVT(i)) | |
361 | device_create(&mtd_class, mtd->dev.parent, | |
362 | MTD_DEVT(i) + 1, | |
363 | NULL, "mtd%dro", i); | |
364 | ||
365 | DEBUG(0, "mtd: Giving out device %d to %s\n", i, mtd->name); | |
366 | /* No need to get a refcount on the module containing | |
367 | the notifier, since we hold the mtd_table_mutex */ | |
368 | list_for_each_entry(not, &mtd_notifiers, list) | |
369 | not->add(mtd); | |
370 | ||
371 | mutex_unlock(&mtd_table_mutex); | |
372 | /* We _know_ we aren't being removed, because | |
373 | our caller is still holding us here. So none | |
374 | of this try_ nonsense, and no bitching about it | |
375 | either. :) */ | |
376 | __module_get(THIS_MODULE); | |
377 | return 0; | |
97894cda | 378 | |
b520e412 BH |
379 | fail_added: |
380 | idr_remove(&mtd_idr, i); | |
381 | fail_locked: | |
48b19268 | 382 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
383 | return 1; |
384 | } | |
385 | ||
386 | /** | |
387 | * del_mtd_device - unregister an MTD device | |
388 | * @mtd: pointer to MTD device info structure | |
389 | * | |
390 | * Remove a device from the list of MTD devices present in the system, | |
391 | * and notify each currently active MTD 'user' of its departure. | |
392 | * Returns zero on success or 1 on failure, which currently will happen | |
393 | * if the requested device does not appear to be present in the list. | |
394 | */ | |
395 | ||
eea72d5f | 396 | int del_mtd_device(struct mtd_info *mtd) |
1da177e4 LT |
397 | { |
398 | int ret; | |
75c0b84d | 399 | struct mtd_notifier *not; |
97894cda | 400 | |
48b19268 | 401 | mutex_lock(&mtd_table_mutex); |
1da177e4 | 402 | |
b520e412 | 403 | if (idr_find(&mtd_idr, mtd->index) != mtd) { |
1da177e4 | 404 | ret = -ENODEV; |
75c0b84d ML |
405 | goto out_error; |
406 | } | |
407 | ||
408 | /* No need to get a refcount on the module containing | |
409 | the notifier, since we hold the mtd_table_mutex */ | |
410 | list_for_each_entry(not, &mtd_notifiers, list) | |
411 | not->remove(mtd); | |
412 | ||
413 | if (mtd->usecount) { | |
97894cda | 414 | printk(KERN_NOTICE "Removing MTD device #%d (%s) with use count %d\n", |
1da177e4 LT |
415 | mtd->index, mtd->name, mtd->usecount); |
416 | ret = -EBUSY; | |
417 | } else { | |
694bb7fc KC |
418 | device_unregister(&mtd->dev); |
419 | ||
b520e412 | 420 | idr_remove(&mtd_idr, mtd->index); |
1da177e4 LT |
421 | |
422 | module_put(THIS_MODULE); | |
423 | ret = 0; | |
424 | } | |
425 | ||
75c0b84d | 426 | out_error: |
48b19268 | 427 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
428 | return ret; |
429 | } | |
430 | ||
f5671ab3 JI |
431 | /** |
432 | * mtd_device_register - register an MTD device. | |
433 | * | |
434 | * @master: the MTD device to register | |
435 | * @parts: the partitions to register - only valid if nr_parts > 0 | |
436 | * @nr_parts: the number of partitions in parts. If zero then the full MTD | |
437 | * device is registered | |
438 | * | |
439 | * Register an MTD device with the system and optionally, a number of | |
440 | * partitions. If nr_parts is 0 then the whole device is registered, otherwise | |
441 | * only the partitions are registered. To register both the full device *and* | |
442 | * the partitions, call mtd_device_register() twice, once with nr_parts == 0 | |
443 | * and once equal to the number of partitions. | |
444 | */ | |
445 | int mtd_device_register(struct mtd_info *master, | |
446 | const struct mtd_partition *parts, | |
447 | int nr_parts) | |
448 | { | |
449 | return parts ? add_mtd_partitions(master, parts, nr_parts) : | |
450 | add_mtd_device(master); | |
451 | } | |
452 | EXPORT_SYMBOL_GPL(mtd_device_register); | |
453 | ||
1c4c215c DES |
454 | /** |
455 | * mtd_device_parse_register - parse partitions and register an MTD device. | |
456 | * | |
457 | * @mtd: the MTD device to register | |
458 | * @types: the list of MTD partition probes to try, see | |
459 | * 'parse_mtd_partitions()' for more information | |
460 | * @origin: start address of MTD device, %0 unless you are sure you need this. | |
461 | * @parts: fallback partition information to register, if parsing fails; | |
462 | * only valid if %nr_parts > %0 | |
463 | * @nr_parts: the number of partitions in parts, if zero then the full | |
464 | * MTD device is registered if no partition info is found | |
465 | * | |
466 | * This function aggregates MTD partitions parsing (done by | |
467 | * 'parse_mtd_partitions()') and MTD device and partitions registering. It | |
468 | * basically follows the most common pattern found in many MTD drivers: | |
469 | * | |
470 | * * It first tries to probe partitions on MTD device @mtd using parsers | |
471 | * specified in @types (if @types is %NULL, then the default list of parsers | |
472 | * is used, see 'parse_mtd_partitions()' for more information). If none are | |
473 | * found this functions tries to fallback to information specified in | |
474 | * @parts/@nr_parts. | |
475 | * * If any parititioning info was found, this function registers the found | |
476 | * partitions. | |
477 | * * If no partitions were found this function just registers the MTD device | |
478 | * @mtd and exits. | |
479 | * | |
480 | * Returns zero in case of success and a negative error code in case of failure. | |
481 | */ | |
482 | int mtd_device_parse_register(struct mtd_info *mtd, const char **types, | |
483 | unsigned long origin, | |
484 | const struct mtd_partition *parts, | |
485 | int nr_parts) | |
486 | { | |
487 | int err; | |
488 | struct mtd_partition *real_parts; | |
489 | ||
490 | err = parse_mtd_partitions(mtd, types, &real_parts, origin); | |
491 | if (err <= 0 && nr_parts) { | |
492 | real_parts = kmemdup(parts, sizeof(*parts) * nr_parts, | |
493 | GFP_KERNEL); | |
494 | err = nr_parts; | |
495 | if (!parts) | |
496 | err = -ENOMEM; | |
497 | } | |
498 | ||
499 | if (err > 0) { | |
500 | err = add_mtd_partitions(mtd, real_parts, err); | |
501 | kfree(real_parts); | |
502 | } else if (err == 0) { | |
503 | err = add_mtd_device(mtd); | |
504 | if (err == 1) | |
505 | err = -ENODEV; | |
506 | } | |
507 | ||
508 | return err; | |
509 | } | |
510 | EXPORT_SYMBOL_GPL(mtd_device_parse_register); | |
511 | ||
f5671ab3 JI |
512 | /** |
513 | * mtd_device_unregister - unregister an existing MTD device. | |
514 | * | |
515 | * @master: the MTD device to unregister. This will unregister both the master | |
516 | * and any partitions if registered. | |
517 | */ | |
518 | int mtd_device_unregister(struct mtd_info *master) | |
519 | { | |
520 | int err; | |
521 | ||
522 | err = del_mtd_partitions(master); | |
523 | if (err) | |
524 | return err; | |
525 | ||
526 | if (!device_is_registered(&master->dev)) | |
527 | return 0; | |
528 | ||
529 | return del_mtd_device(master); | |
530 | } | |
531 | EXPORT_SYMBOL_GPL(mtd_device_unregister); | |
532 | ||
1da177e4 LT |
533 | /** |
534 | * register_mtd_user - register a 'user' of MTD devices. | |
535 | * @new: pointer to notifier info structure | |
536 | * | |
537 | * Registers a pair of callbacks function to be called upon addition | |
538 | * or removal of MTD devices. Causes the 'add' callback to be immediately | |
539 | * invoked for each MTD device currently present in the system. | |
540 | */ | |
541 | ||
542 | void register_mtd_user (struct mtd_notifier *new) | |
543 | { | |
f1332ba2 | 544 | struct mtd_info *mtd; |
1da177e4 | 545 | |
48b19268 | 546 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
547 | |
548 | list_add(&new->list, &mtd_notifiers); | |
549 | ||
d5ca5129 | 550 | __module_get(THIS_MODULE); |
97894cda | 551 | |
f1332ba2 BH |
552 | mtd_for_each_device(mtd) |
553 | new->add(mtd); | |
1da177e4 | 554 | |
48b19268 | 555 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
556 | } |
557 | ||
558 | /** | |
49450795 AB |
559 | * unregister_mtd_user - unregister a 'user' of MTD devices. |
560 | * @old: pointer to notifier info structure | |
1da177e4 LT |
561 | * |
562 | * Removes a callback function pair from the list of 'users' to be | |
563 | * notified upon addition or removal of MTD devices. Causes the | |
564 | * 'remove' callback to be immediately invoked for each MTD device | |
565 | * currently present in the system. | |
566 | */ | |
567 | ||
568 | int unregister_mtd_user (struct mtd_notifier *old) | |
569 | { | |
f1332ba2 | 570 | struct mtd_info *mtd; |
1da177e4 | 571 | |
48b19268 | 572 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
573 | |
574 | module_put(THIS_MODULE); | |
575 | ||
f1332ba2 BH |
576 | mtd_for_each_device(mtd) |
577 | old->remove(mtd); | |
97894cda | 578 | |
1da177e4 | 579 | list_del(&old->list); |
48b19268 | 580 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
581 | return 0; |
582 | } | |
583 | ||
584 | ||
585 | /** | |
586 | * get_mtd_device - obtain a validated handle for an MTD device | |
587 | * @mtd: last known address of the required MTD device | |
588 | * @num: internal device number of the required MTD device | |
589 | * | |
590 | * Given a number and NULL address, return the num'th entry in the device | |
591 | * table, if any. Given an address and num == -1, search the device table | |
592 | * for a device with that address and return if it's still present. Given | |
9c74034f AB |
593 | * both, return the num'th driver only if its address matches. Return |
594 | * error code if not. | |
1da177e4 | 595 | */ |
97894cda | 596 | |
1da177e4 LT |
597 | struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num) |
598 | { | |
f1332ba2 BH |
599 | struct mtd_info *ret = NULL, *other; |
600 | int err = -ENODEV; | |
1da177e4 | 601 | |
48b19268 | 602 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
603 | |
604 | if (num == -1) { | |
f1332ba2 BH |
605 | mtd_for_each_device(other) { |
606 | if (other == mtd) { | |
607 | ret = mtd; | |
608 | break; | |
609 | } | |
610 | } | |
b520e412 BH |
611 | } else if (num >= 0) { |
612 | ret = idr_find(&mtd_idr, num); | |
1da177e4 LT |
613 | if (mtd && mtd != ret) |
614 | ret = NULL; | |
615 | } | |
616 | ||
3bd45657 ML |
617 | if (!ret) { |
618 | ret = ERR_PTR(err); | |
619 | goto out; | |
9fe912ce | 620 | } |
1da177e4 | 621 | |
3bd45657 ML |
622 | err = __get_mtd_device(ret); |
623 | if (err) | |
624 | ret = ERR_PTR(err); | |
625 | out: | |
9c74034f AB |
626 | mutex_unlock(&mtd_table_mutex); |
627 | return ret; | |
3bd45657 | 628 | } |
1da177e4 | 629 | |
3bd45657 ML |
630 | |
631 | int __get_mtd_device(struct mtd_info *mtd) | |
632 | { | |
633 | int err; | |
634 | ||
635 | if (!try_module_get(mtd->owner)) | |
636 | return -ENODEV; | |
637 | ||
638 | if (mtd->get_device) { | |
3bd45657 ML |
639 | err = mtd->get_device(mtd); |
640 | ||
641 | if (err) { | |
642 | module_put(mtd->owner); | |
643 | return err; | |
644 | } | |
645 | } | |
646 | mtd->usecount++; | |
647 | return 0; | |
1da177e4 LT |
648 | } |
649 | ||
7799308f AB |
650 | /** |
651 | * get_mtd_device_nm - obtain a validated handle for an MTD device by | |
652 | * device name | |
653 | * @name: MTD device name to open | |
654 | * | |
655 | * This function returns MTD device description structure in case of | |
656 | * success and an error code in case of failure. | |
657 | */ | |
658 | ||
659 | struct mtd_info *get_mtd_device_nm(const char *name) | |
660 | { | |
f1332ba2 BH |
661 | int err = -ENODEV; |
662 | struct mtd_info *mtd = NULL, *other; | |
7799308f AB |
663 | |
664 | mutex_lock(&mtd_table_mutex); | |
665 | ||
f1332ba2 BH |
666 | mtd_for_each_device(other) { |
667 | if (!strcmp(name, other->name)) { | |
668 | mtd = other; | |
7799308f AB |
669 | break; |
670 | } | |
671 | } | |
672 | ||
9fe912ce | 673 | if (!mtd) |
7799308f AB |
674 | goto out_unlock; |
675 | ||
52534f2d WG |
676 | err = __get_mtd_device(mtd); |
677 | if (err) | |
7799308f AB |
678 | goto out_unlock; |
679 | ||
9fe912ce AB |
680 | mutex_unlock(&mtd_table_mutex); |
681 | return mtd; | |
7799308f AB |
682 | |
683 | out_unlock: | |
684 | mutex_unlock(&mtd_table_mutex); | |
9fe912ce | 685 | return ERR_PTR(err); |
7799308f AB |
686 | } |
687 | ||
1da177e4 LT |
688 | void put_mtd_device(struct mtd_info *mtd) |
689 | { | |
48b19268 | 690 | mutex_lock(&mtd_table_mutex); |
3bd45657 ML |
691 | __put_mtd_device(mtd); |
692 | mutex_unlock(&mtd_table_mutex); | |
693 | ||
694 | } | |
695 | ||
696 | void __put_mtd_device(struct mtd_info *mtd) | |
697 | { | |
698 | --mtd->usecount; | |
699 | BUG_ON(mtd->usecount < 0); | |
700 | ||
9fe912ce AB |
701 | if (mtd->put_device) |
702 | mtd->put_device(mtd); | |
1da177e4 LT |
703 | |
704 | module_put(mtd->owner); | |
705 | } | |
706 | ||
707 | /* default_mtd_writev - default mtd writev method for MTD devices that | |
dd36f267 | 708 | * don't implement their own |
1da177e4 LT |
709 | */ |
710 | ||
711 | int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs, | |
712 | unsigned long count, loff_t to, size_t *retlen) | |
713 | { | |
714 | unsigned long i; | |
715 | size_t totlen = 0, thislen; | |
716 | int ret = 0; | |
717 | ||
718 | if(!mtd->write) { | |
719 | ret = -EROFS; | |
720 | } else { | |
721 | for (i=0; i<count; i++) { | |
722 | if (!vecs[i].iov_len) | |
723 | continue; | |
724 | ret = mtd->write(mtd, to, vecs[i].iov_len, &thislen, vecs[i].iov_base); | |
725 | totlen += thislen; | |
726 | if (ret || thislen != vecs[i].iov_len) | |
727 | break; | |
728 | to += vecs[i].iov_len; | |
729 | } | |
730 | } | |
731 | if (retlen) | |
732 | *retlen = totlen; | |
733 | return ret; | |
734 | } | |
735 | ||
33b53716 GE |
736 | /** |
737 | * mtd_kmalloc_up_to - allocate a contiguous buffer up to the specified size | |
738 | * @size: A pointer to the ideal or maximum size of the allocation. Points | |
739 | * to the actual allocation size on success. | |
740 | * | |
741 | * This routine attempts to allocate a contiguous kernel buffer up to | |
742 | * the specified size, backing off the size of the request exponentially | |
743 | * until the request succeeds or until the allocation size falls below | |
744 | * the system page size. This attempts to make sure it does not adversely | |
745 | * impact system performance, so when allocating more than one page, we | |
746 | * ask the memory allocator to avoid re-trying, swapping, writing back | |
747 | * or performing I/O. | |
748 | * | |
749 | * Note, this function also makes sure that the allocated buffer is aligned to | |
750 | * the MTD device's min. I/O unit, i.e. the "mtd->writesize" value. | |
751 | * | |
752 | * This is called, for example by mtd_{read,write} and jffs2_scan_medium, | |
753 | * to handle smaller (i.e. degraded) buffer allocations under low- or | |
754 | * fragmented-memory situations where such reduced allocations, from a | |
755 | * requested ideal, are allowed. | |
756 | * | |
757 | * Returns a pointer to the allocated buffer on success; otherwise, NULL. | |
758 | */ | |
759 | void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size) | |
760 | { | |
761 | gfp_t flags = __GFP_NOWARN | __GFP_WAIT | | |
762 | __GFP_NORETRY | __GFP_NO_KSWAPD; | |
763 | size_t min_alloc = max_t(size_t, mtd->writesize, PAGE_SIZE); | |
764 | void *kbuf; | |
765 | ||
766 | *size = min_t(size_t, *size, KMALLOC_MAX_SIZE); | |
767 | ||
768 | while (*size > min_alloc) { | |
769 | kbuf = kmalloc(*size, flags); | |
770 | if (kbuf) | |
771 | return kbuf; | |
772 | ||
773 | *size >>= 1; | |
774 | *size = ALIGN(*size, mtd->writesize); | |
775 | } | |
776 | ||
777 | /* | |
778 | * For the last resort allocation allow 'kmalloc()' to do all sorts of | |
779 | * things (write-back, dropping caches, etc) by using GFP_KERNEL. | |
780 | */ | |
781 | return kmalloc(*size, GFP_KERNEL); | |
782 | } | |
783 | ||
dd36f267 DW |
784 | EXPORT_SYMBOL_GPL(get_mtd_device); |
785 | EXPORT_SYMBOL_GPL(get_mtd_device_nm); | |
3bd45657 | 786 | EXPORT_SYMBOL_GPL(__get_mtd_device); |
dd36f267 | 787 | EXPORT_SYMBOL_GPL(put_mtd_device); |
3bd45657 | 788 | EXPORT_SYMBOL_GPL(__put_mtd_device); |
dd36f267 DW |
789 | EXPORT_SYMBOL_GPL(register_mtd_user); |
790 | EXPORT_SYMBOL_GPL(unregister_mtd_user); | |
791 | EXPORT_SYMBOL_GPL(default_mtd_writev); | |
33b53716 | 792 | EXPORT_SYMBOL_GPL(mtd_kmalloc_up_to); |
1da177e4 | 793 | |
2d2dce0e PM |
794 | #ifdef CONFIG_PROC_FS |
795 | ||
1da177e4 LT |
796 | /*====================================================================*/ |
797 | /* Support for /proc/mtd */ | |
798 | ||
1da177e4 LT |
799 | static struct proc_dir_entry *proc_mtd; |
800 | ||
447d9bd8 | 801 | static int mtd_proc_show(struct seq_file *m, void *v) |
1da177e4 | 802 | { |
f1332ba2 | 803 | struct mtd_info *mtd; |
1da177e4 | 804 | |
447d9bd8 | 805 | seq_puts(m, "dev: size erasesize name\n"); |
48b19268 | 806 | mutex_lock(&mtd_table_mutex); |
f1332ba2 | 807 | mtd_for_each_device(mtd) { |
447d9bd8 AD |
808 | seq_printf(m, "mtd%d: %8.8llx %8.8x \"%s\"\n", |
809 | mtd->index, (unsigned long long)mtd->size, | |
810 | mtd->erasesize, mtd->name); | |
d5ca5129 | 811 | } |
48b19268 | 812 | mutex_unlock(&mtd_table_mutex); |
d5ca5129 | 813 | return 0; |
1da177e4 LT |
814 | } |
815 | ||
447d9bd8 AD |
816 | static int mtd_proc_open(struct inode *inode, struct file *file) |
817 | { | |
818 | return single_open(file, mtd_proc_show, NULL); | |
819 | } | |
820 | ||
821 | static const struct file_operations mtd_proc_ops = { | |
822 | .open = mtd_proc_open, | |
823 | .read = seq_read, | |
824 | .llseek = seq_lseek, | |
825 | .release = single_release, | |
826 | }; | |
45b09076 KC |
827 | #endif /* CONFIG_PROC_FS */ |
828 | ||
1da177e4 LT |
829 | /*====================================================================*/ |
830 | /* Init code */ | |
831 | ||
0661b1ac JA |
832 | static int __init mtd_bdi_init(struct backing_dev_info *bdi, const char *name) |
833 | { | |
834 | int ret; | |
835 | ||
836 | ret = bdi_init(bdi); | |
837 | if (!ret) | |
838 | ret = bdi_register(bdi, NULL, name); | |
839 | ||
840 | if (ret) | |
841 | bdi_destroy(bdi); | |
842 | ||
843 | return ret; | |
844 | } | |
845 | ||
1da177e4 LT |
846 | static int __init init_mtd(void) |
847 | { | |
15bce40c | 848 | int ret; |
0661b1ac | 849 | |
15bce40c | 850 | ret = class_register(&mtd_class); |
0661b1ac JA |
851 | if (ret) |
852 | goto err_reg; | |
853 | ||
854 | ret = mtd_bdi_init(&mtd_bdi_unmappable, "mtd-unmap"); | |
855 | if (ret) | |
856 | goto err_bdi1; | |
857 | ||
858 | ret = mtd_bdi_init(&mtd_bdi_ro_mappable, "mtd-romap"); | |
859 | if (ret) | |
860 | goto err_bdi2; | |
861 | ||
862 | ret = mtd_bdi_init(&mtd_bdi_rw_mappable, "mtd-rwmap"); | |
863 | if (ret) | |
864 | goto err_bdi3; | |
694bb7fc | 865 | |
45b09076 | 866 | #ifdef CONFIG_PROC_FS |
447d9bd8 | 867 | proc_mtd = proc_create("mtd", 0, NULL, &mtd_proc_ops); |
45b09076 | 868 | #endif /* CONFIG_PROC_FS */ |
1da177e4 | 869 | return 0; |
0661b1ac JA |
870 | |
871 | err_bdi3: | |
872 | bdi_destroy(&mtd_bdi_ro_mappable); | |
873 | err_bdi2: | |
874 | bdi_destroy(&mtd_bdi_unmappable); | |
875 | err_bdi1: | |
876 | class_unregister(&mtd_class); | |
877 | err_reg: | |
878 | pr_err("Error registering mtd class or bdi: %d\n", ret); | |
879 | return ret; | |
1da177e4 LT |
880 | } |
881 | ||
882 | static void __exit cleanup_mtd(void) | |
883 | { | |
45b09076 | 884 | #ifdef CONFIG_PROC_FS |
d5ca5129 | 885 | if (proc_mtd) |
1da177e4 | 886 | remove_proc_entry( "mtd", NULL); |
45b09076 | 887 | #endif /* CONFIG_PROC_FS */ |
15bce40c | 888 | class_unregister(&mtd_class); |
0661b1ac JA |
889 | bdi_destroy(&mtd_bdi_unmappable); |
890 | bdi_destroy(&mtd_bdi_ro_mappable); | |
891 | bdi_destroy(&mtd_bdi_rw_mappable); | |
1da177e4 LT |
892 | } |
893 | ||
894 | module_init(init_mtd); | |
895 | module_exit(cleanup_mtd); | |
896 | ||
1da177e4 LT |
897 | MODULE_LICENSE("GPL"); |
898 | MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>"); | |
899 | MODULE_DESCRIPTION("Core MTD registration and access routines"); |