Commit | Line | Data |
---|---|---|
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 | { | |
d5de20a9 AB |
110 | struct mtd_info *mtd = dev_get_drvdata(dev); |
111 | dev_t index = MTD_DEVT(mtd->index); | |
1f24b5a8 DB |
112 | |
113 | /* remove /dev/mtdXro node if needed */ | |
2fdb1144 | 114 | if (index) |
15bce40c DW |
115 | device_destroy(&mtd_class, index + 1); |
116 | } | |
117 | ||
118 | static int mtd_cls_suspend(struct device *dev, pm_message_t state) | |
119 | { | |
d5de20a9 | 120 | struct mtd_info *mtd = dev_get_drvdata(dev); |
6afc4fdb SB |
121 | |
122 | if (mtd && mtd->suspend) | |
3fe4bae8 | 123 | return mtd_suspend(mtd); |
15bce40c DW |
124 | else |
125 | return 0; | |
126 | } | |
127 | ||
128 | static int mtd_cls_resume(struct device *dev) | |
129 | { | |
d5de20a9 | 130 | struct mtd_info *mtd = dev_get_drvdata(dev); |
15bce40c | 131 | |
6afc4fdb | 132 | if (mtd && mtd->resume) |
ead995f8 | 133 | mtd_resume(mtd); |
15bce40c | 134 | return 0; |
1f24b5a8 DB |
135 | } |
136 | ||
137 | static ssize_t mtd_type_show(struct device *dev, | |
138 | struct device_attribute *attr, char *buf) | |
139 | { | |
d5de20a9 | 140 | struct mtd_info *mtd = dev_get_drvdata(dev); |
1f24b5a8 DB |
141 | char *type; |
142 | ||
143 | switch (mtd->type) { | |
144 | case MTD_ABSENT: | |
145 | type = "absent"; | |
146 | break; | |
147 | case MTD_RAM: | |
148 | type = "ram"; | |
149 | break; | |
150 | case MTD_ROM: | |
151 | type = "rom"; | |
152 | break; | |
153 | case MTD_NORFLASH: | |
154 | type = "nor"; | |
155 | break; | |
156 | case MTD_NANDFLASH: | |
157 | type = "nand"; | |
158 | break; | |
159 | case MTD_DATAFLASH: | |
160 | type = "dataflash"; | |
161 | break; | |
162 | case MTD_UBIVOLUME: | |
163 | type = "ubi"; | |
164 | break; | |
165 | default: | |
166 | type = "unknown"; | |
167 | } | |
168 | ||
169 | return snprintf(buf, PAGE_SIZE, "%s\n", type); | |
170 | } | |
694bb7fc KC |
171 | static DEVICE_ATTR(type, S_IRUGO, mtd_type_show, NULL); |
172 | ||
173 | static ssize_t mtd_flags_show(struct device *dev, | |
174 | struct device_attribute *attr, char *buf) | |
175 | { | |
d5de20a9 | 176 | struct mtd_info *mtd = dev_get_drvdata(dev); |
694bb7fc KC |
177 | |
178 | return snprintf(buf, PAGE_SIZE, "0x%lx\n", (unsigned long)mtd->flags); | |
179 | ||
180 | } | |
181 | static DEVICE_ATTR(flags, S_IRUGO, mtd_flags_show, NULL); | |
182 | ||
183 | static ssize_t mtd_size_show(struct device *dev, | |
184 | struct device_attribute *attr, char *buf) | |
185 | { | |
d5de20a9 | 186 | struct mtd_info *mtd = dev_get_drvdata(dev); |
694bb7fc KC |
187 | |
188 | return snprintf(buf, PAGE_SIZE, "%llu\n", | |
189 | (unsigned long long)mtd->size); | |
190 | ||
191 | } | |
192 | static DEVICE_ATTR(size, S_IRUGO, mtd_size_show, NULL); | |
193 | ||
194 | static ssize_t mtd_erasesize_show(struct device *dev, | |
195 | struct device_attribute *attr, char *buf) | |
196 | { | |
d5de20a9 | 197 | struct mtd_info *mtd = dev_get_drvdata(dev); |
694bb7fc KC |
198 | |
199 | return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->erasesize); | |
200 | ||
201 | } | |
202 | static DEVICE_ATTR(erasesize, S_IRUGO, mtd_erasesize_show, NULL); | |
203 | ||
204 | static ssize_t mtd_writesize_show(struct device *dev, | |
205 | struct device_attribute *attr, char *buf) | |
206 | { | |
d5de20a9 | 207 | struct mtd_info *mtd = dev_get_drvdata(dev); |
694bb7fc KC |
208 | |
209 | return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->writesize); | |
210 | ||
211 | } | |
212 | static DEVICE_ATTR(writesize, S_IRUGO, mtd_writesize_show, NULL); | |
213 | ||
e7693548 AB |
214 | static ssize_t mtd_subpagesize_show(struct device *dev, |
215 | struct device_attribute *attr, char *buf) | |
216 | { | |
d5de20a9 | 217 | struct mtd_info *mtd = dev_get_drvdata(dev); |
e7693548 AB |
218 | unsigned int subpagesize = mtd->writesize >> mtd->subpage_sft; |
219 | ||
220 | return snprintf(buf, PAGE_SIZE, "%u\n", subpagesize); | |
221 | ||
222 | } | |
223 | static DEVICE_ATTR(subpagesize, S_IRUGO, mtd_subpagesize_show, NULL); | |
224 | ||
694bb7fc KC |
225 | static ssize_t mtd_oobsize_show(struct device *dev, |
226 | struct device_attribute *attr, char *buf) | |
227 | { | |
d5de20a9 | 228 | struct mtd_info *mtd = dev_get_drvdata(dev); |
694bb7fc KC |
229 | |
230 | return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->oobsize); | |
231 | ||
232 | } | |
233 | static DEVICE_ATTR(oobsize, S_IRUGO, mtd_oobsize_show, NULL); | |
234 | ||
235 | static ssize_t mtd_numeraseregions_show(struct device *dev, | |
236 | struct device_attribute *attr, char *buf) | |
237 | { | |
d5de20a9 | 238 | struct mtd_info *mtd = dev_get_drvdata(dev); |
694bb7fc KC |
239 | |
240 | return snprintf(buf, PAGE_SIZE, "%u\n", mtd->numeraseregions); | |
241 | ||
242 | } | |
243 | static DEVICE_ATTR(numeraseregions, S_IRUGO, mtd_numeraseregions_show, | |
244 | NULL); | |
245 | ||
246 | static ssize_t mtd_name_show(struct device *dev, | |
247 | struct device_attribute *attr, char *buf) | |
248 | { | |
d5de20a9 | 249 | struct mtd_info *mtd = dev_get_drvdata(dev); |
694bb7fc KC |
250 | |
251 | return snprintf(buf, PAGE_SIZE, "%s\n", mtd->name); | |
252 | ||
253 | } | |
254 | static DEVICE_ATTR(name, S_IRUGO, mtd_name_show, NULL); | |
1f24b5a8 DB |
255 | |
256 | static struct attribute *mtd_attrs[] = { | |
694bb7fc KC |
257 | &dev_attr_type.attr, |
258 | &dev_attr_flags.attr, | |
259 | &dev_attr_size.attr, | |
260 | &dev_attr_erasesize.attr, | |
261 | &dev_attr_writesize.attr, | |
e7693548 | 262 | &dev_attr_subpagesize.attr, |
694bb7fc KC |
263 | &dev_attr_oobsize.attr, |
264 | &dev_attr_numeraseregions.attr, | |
265 | &dev_attr_name.attr, | |
1f24b5a8 DB |
266 | NULL, |
267 | }; | |
268 | ||
fca91088 | 269 | static struct attribute_group mtd_group = { |
1f24b5a8 DB |
270 | .attrs = mtd_attrs, |
271 | }; | |
272 | ||
6469f540 | 273 | static const struct attribute_group *mtd_groups[] = { |
1f24b5a8 DB |
274 | &mtd_group, |
275 | NULL, | |
276 | }; | |
277 | ||
278 | static struct device_type mtd_devtype = { | |
279 | .name = "mtd", | |
280 | .groups = mtd_groups, | |
281 | .release = mtd_release, | |
282 | }; | |
283 | ||
1da177e4 LT |
284 | /** |
285 | * add_mtd_device - register an MTD device | |
286 | * @mtd: pointer to new MTD device info structure | |
287 | * | |
288 | * Add a device to the list of MTD devices present in the system, and | |
289 | * notify each currently active MTD 'user' of its arrival. Returns | |
290 | * zero on success or 1 on failure, which currently will only happen | |
b520e412 | 291 | * if there is insufficient memory or a sysfs error. |
1da177e4 LT |
292 | */ |
293 | ||
294 | int add_mtd_device(struct mtd_info *mtd) | |
295 | { | |
b520e412 BH |
296 | struct mtd_notifier *not; |
297 | int i, error; | |
1da177e4 | 298 | |
402d3265 DH |
299 | if (!mtd->backing_dev_info) { |
300 | switch (mtd->type) { | |
301 | case MTD_RAM: | |
302 | mtd->backing_dev_info = &mtd_bdi_rw_mappable; | |
303 | break; | |
304 | case MTD_ROM: | |
305 | mtd->backing_dev_info = &mtd_bdi_ro_mappable; | |
306 | break; | |
307 | default: | |
308 | mtd->backing_dev_info = &mtd_bdi_unmappable; | |
309 | break; | |
310 | } | |
311 | } | |
312 | ||
783ed81f | 313 | BUG_ON(mtd->writesize == 0); |
48b19268 | 314 | mutex_lock(&mtd_table_mutex); |
1da177e4 | 315 | |
b520e412 BH |
316 | do { |
317 | if (!idr_pre_get(&mtd_idr, GFP_KERNEL)) | |
318 | goto fail_locked; | |
319 | error = idr_get_new(&mtd_idr, mtd, &i); | |
320 | } while (error == -EAGAIN); | |
187ef152 | 321 | |
b520e412 BH |
322 | if (error) |
323 | goto fail_locked; | |
1f24b5a8 | 324 | |
b520e412 BH |
325 | mtd->index = i; |
326 | mtd->usecount = 0; | |
327 | ||
328 | if (is_power_of_2(mtd->erasesize)) | |
329 | mtd->erasesize_shift = ffs(mtd->erasesize) - 1; | |
330 | else | |
331 | mtd->erasesize_shift = 0; | |
332 | ||
333 | if (is_power_of_2(mtd->writesize)) | |
334 | mtd->writesize_shift = ffs(mtd->writesize) - 1; | |
335 | else | |
336 | mtd->writesize_shift = 0; | |
337 | ||
338 | mtd->erasesize_mask = (1 << mtd->erasesize_shift) - 1; | |
339 | mtd->writesize_mask = (1 << mtd->writesize_shift) - 1; | |
340 | ||
341 | /* Some chips always power up locked. Unlock them now */ | |
342 | if ((mtd->flags & MTD_WRITEABLE) | |
343 | && (mtd->flags & MTD_POWERUP_LOCK) && mtd->unlock) { | |
b66005cd | 344 | if (mtd_unlock(mtd, 0, mtd->size)) |
b520e412 BH |
345 | printk(KERN_WARNING |
346 | "%s: unlock failed, writes may not work\n", | |
347 | mtd->name); | |
348 | } | |
349 | ||
350 | /* Caller should have set dev.parent to match the | |
351 | * physical device. | |
352 | */ | |
353 | mtd->dev.type = &mtd_devtype; | |
354 | mtd->dev.class = &mtd_class; | |
355 | mtd->dev.devt = MTD_DEVT(i); | |
356 | dev_set_name(&mtd->dev, "mtd%d", i); | |
357 | dev_set_drvdata(&mtd->dev, mtd); | |
358 | if (device_register(&mtd->dev) != 0) | |
359 | goto fail_added; | |
360 | ||
361 | if (MTD_DEVT(i)) | |
362 | device_create(&mtd_class, mtd->dev.parent, | |
363 | MTD_DEVT(i) + 1, | |
364 | NULL, "mtd%dro", i); | |
365 | ||
289c0522 | 366 | pr_debug("mtd: Giving out device %d to %s\n", i, mtd->name); |
b520e412 BH |
367 | /* No need to get a refcount on the module containing |
368 | the notifier, since we hold the mtd_table_mutex */ | |
369 | list_for_each_entry(not, &mtd_notifiers, list) | |
370 | not->add(mtd); | |
371 | ||
372 | mutex_unlock(&mtd_table_mutex); | |
373 | /* We _know_ we aren't being removed, because | |
374 | our caller is still holding us here. So none | |
375 | of this try_ nonsense, and no bitching about it | |
376 | either. :) */ | |
377 | __module_get(THIS_MODULE); | |
378 | return 0; | |
97894cda | 379 | |
b520e412 BH |
380 | fail_added: |
381 | idr_remove(&mtd_idr, i); | |
382 | fail_locked: | |
48b19268 | 383 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
384 | return 1; |
385 | } | |
386 | ||
387 | /** | |
388 | * del_mtd_device - unregister an MTD device | |
389 | * @mtd: pointer to MTD device info structure | |
390 | * | |
391 | * Remove a device from the list of MTD devices present in the system, | |
392 | * and notify each currently active MTD 'user' of its departure. | |
393 | * Returns zero on success or 1 on failure, which currently will happen | |
394 | * if the requested device does not appear to be present in the list. | |
395 | */ | |
396 | ||
eea72d5f | 397 | int del_mtd_device(struct mtd_info *mtd) |
1da177e4 LT |
398 | { |
399 | int ret; | |
75c0b84d | 400 | struct mtd_notifier *not; |
97894cda | 401 | |
48b19268 | 402 | mutex_lock(&mtd_table_mutex); |
1da177e4 | 403 | |
b520e412 | 404 | if (idr_find(&mtd_idr, mtd->index) != mtd) { |
1da177e4 | 405 | ret = -ENODEV; |
75c0b84d ML |
406 | goto out_error; |
407 | } | |
408 | ||
409 | /* No need to get a refcount on the module containing | |
410 | the notifier, since we hold the mtd_table_mutex */ | |
411 | list_for_each_entry(not, &mtd_notifiers, list) | |
412 | not->remove(mtd); | |
413 | ||
414 | if (mtd->usecount) { | |
97894cda | 415 | printk(KERN_NOTICE "Removing MTD device #%d (%s) with use count %d\n", |
1da177e4 LT |
416 | mtd->index, mtd->name, mtd->usecount); |
417 | ret = -EBUSY; | |
418 | } else { | |
694bb7fc KC |
419 | device_unregister(&mtd->dev); |
420 | ||
b520e412 | 421 | idr_remove(&mtd_idr, mtd->index); |
1da177e4 LT |
422 | |
423 | module_put(THIS_MODULE); | |
424 | ret = 0; | |
425 | } | |
426 | ||
75c0b84d | 427 | out_error: |
48b19268 | 428 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
429 | return ret; |
430 | } | |
431 | ||
1c4c215c DES |
432 | /** |
433 | * mtd_device_parse_register - parse partitions and register an MTD device. | |
434 | * | |
435 | * @mtd: the MTD device to register | |
436 | * @types: the list of MTD partition probes to try, see | |
437 | * 'parse_mtd_partitions()' for more information | |
c7975330 | 438 | * @parser_data: MTD partition parser-specific data |
1c4c215c DES |
439 | * @parts: fallback partition information to register, if parsing fails; |
440 | * only valid if %nr_parts > %0 | |
441 | * @nr_parts: the number of partitions in parts, if zero then the full | |
442 | * MTD device is registered if no partition info is found | |
443 | * | |
444 | * This function aggregates MTD partitions parsing (done by | |
445 | * 'parse_mtd_partitions()') and MTD device and partitions registering. It | |
446 | * basically follows the most common pattern found in many MTD drivers: | |
447 | * | |
448 | * * It first tries to probe partitions on MTD device @mtd using parsers | |
449 | * specified in @types (if @types is %NULL, then the default list of parsers | |
450 | * is used, see 'parse_mtd_partitions()' for more information). If none are | |
451 | * found this functions tries to fallback to information specified in | |
452 | * @parts/@nr_parts. | |
92394b5c | 453 | * * If any partitioning info was found, this function registers the found |
1c4c215c DES |
454 | * partitions. |
455 | * * If no partitions were found this function just registers the MTD device | |
456 | * @mtd and exits. | |
457 | * | |
458 | * Returns zero in case of success and a negative error code in case of failure. | |
459 | */ | |
460 | int mtd_device_parse_register(struct mtd_info *mtd, const char **types, | |
c7975330 | 461 | struct mtd_part_parser_data *parser_data, |
1c4c215c DES |
462 | const struct mtd_partition *parts, |
463 | int nr_parts) | |
464 | { | |
465 | int err; | |
466 | struct mtd_partition *real_parts; | |
467 | ||
c7975330 | 468 | err = parse_mtd_partitions(mtd, types, &real_parts, parser_data); |
4d523b60 | 469 | if (err <= 0 && nr_parts && parts) { |
1c4c215c DES |
470 | real_parts = kmemdup(parts, sizeof(*parts) * nr_parts, |
471 | GFP_KERNEL); | |
4d523b60 | 472 | if (!real_parts) |
1c4c215c | 473 | err = -ENOMEM; |
4d523b60 JL |
474 | else |
475 | err = nr_parts; | |
1c4c215c DES |
476 | } |
477 | ||
478 | if (err > 0) { | |
479 | err = add_mtd_partitions(mtd, real_parts, err); | |
480 | kfree(real_parts); | |
481 | } else if (err == 0) { | |
482 | err = add_mtd_device(mtd); | |
483 | if (err == 1) | |
484 | err = -ENODEV; | |
485 | } | |
486 | ||
487 | return err; | |
488 | } | |
489 | EXPORT_SYMBOL_GPL(mtd_device_parse_register); | |
490 | ||
f5671ab3 JI |
491 | /** |
492 | * mtd_device_unregister - unregister an existing MTD device. | |
493 | * | |
494 | * @master: the MTD device to unregister. This will unregister both the master | |
495 | * and any partitions if registered. | |
496 | */ | |
497 | int mtd_device_unregister(struct mtd_info *master) | |
498 | { | |
499 | int err; | |
500 | ||
501 | err = del_mtd_partitions(master); | |
502 | if (err) | |
503 | return err; | |
504 | ||
505 | if (!device_is_registered(&master->dev)) | |
506 | return 0; | |
507 | ||
508 | return del_mtd_device(master); | |
509 | } | |
510 | EXPORT_SYMBOL_GPL(mtd_device_unregister); | |
511 | ||
1da177e4 LT |
512 | /** |
513 | * register_mtd_user - register a 'user' of MTD devices. | |
514 | * @new: pointer to notifier info structure | |
515 | * | |
516 | * Registers a pair of callbacks function to be called upon addition | |
517 | * or removal of MTD devices. Causes the 'add' callback to be immediately | |
518 | * invoked for each MTD device currently present in the system. | |
519 | */ | |
520 | ||
521 | void register_mtd_user (struct mtd_notifier *new) | |
522 | { | |
f1332ba2 | 523 | struct mtd_info *mtd; |
1da177e4 | 524 | |
48b19268 | 525 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
526 | |
527 | list_add(&new->list, &mtd_notifiers); | |
528 | ||
d5ca5129 | 529 | __module_get(THIS_MODULE); |
97894cda | 530 | |
f1332ba2 BH |
531 | mtd_for_each_device(mtd) |
532 | new->add(mtd); | |
1da177e4 | 533 | |
48b19268 | 534 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
535 | } |
536 | ||
537 | /** | |
49450795 AB |
538 | * unregister_mtd_user - unregister a 'user' of MTD devices. |
539 | * @old: pointer to notifier info structure | |
1da177e4 LT |
540 | * |
541 | * Removes a callback function pair from the list of 'users' to be | |
542 | * notified upon addition or removal of MTD devices. Causes the | |
543 | * 'remove' callback to be immediately invoked for each MTD device | |
544 | * currently present in the system. | |
545 | */ | |
546 | ||
547 | int unregister_mtd_user (struct mtd_notifier *old) | |
548 | { | |
f1332ba2 | 549 | struct mtd_info *mtd; |
1da177e4 | 550 | |
48b19268 | 551 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
552 | |
553 | module_put(THIS_MODULE); | |
554 | ||
f1332ba2 BH |
555 | mtd_for_each_device(mtd) |
556 | old->remove(mtd); | |
97894cda | 557 | |
1da177e4 | 558 | list_del(&old->list); |
48b19268 | 559 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
560 | return 0; |
561 | } | |
562 | ||
563 | ||
564 | /** | |
565 | * get_mtd_device - obtain a validated handle for an MTD device | |
566 | * @mtd: last known address of the required MTD device | |
567 | * @num: internal device number of the required MTD device | |
568 | * | |
569 | * Given a number and NULL address, return the num'th entry in the device | |
570 | * table, if any. Given an address and num == -1, search the device table | |
571 | * for a device with that address and return if it's still present. Given | |
9c74034f AB |
572 | * both, return the num'th driver only if its address matches. Return |
573 | * error code if not. | |
1da177e4 | 574 | */ |
97894cda | 575 | |
1da177e4 LT |
576 | struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num) |
577 | { | |
f1332ba2 BH |
578 | struct mtd_info *ret = NULL, *other; |
579 | int err = -ENODEV; | |
1da177e4 | 580 | |
48b19268 | 581 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
582 | |
583 | if (num == -1) { | |
f1332ba2 BH |
584 | mtd_for_each_device(other) { |
585 | if (other == mtd) { | |
586 | ret = mtd; | |
587 | break; | |
588 | } | |
589 | } | |
b520e412 BH |
590 | } else if (num >= 0) { |
591 | ret = idr_find(&mtd_idr, num); | |
1da177e4 LT |
592 | if (mtd && mtd != ret) |
593 | ret = NULL; | |
594 | } | |
595 | ||
3bd45657 ML |
596 | if (!ret) { |
597 | ret = ERR_PTR(err); | |
598 | goto out; | |
9fe912ce | 599 | } |
1da177e4 | 600 | |
3bd45657 ML |
601 | err = __get_mtd_device(ret); |
602 | if (err) | |
603 | ret = ERR_PTR(err); | |
604 | out: | |
9c74034f AB |
605 | mutex_unlock(&mtd_table_mutex); |
606 | return ret; | |
3bd45657 | 607 | } |
1da177e4 | 608 | |
3bd45657 ML |
609 | |
610 | int __get_mtd_device(struct mtd_info *mtd) | |
611 | { | |
612 | int err; | |
613 | ||
614 | if (!try_module_get(mtd->owner)) | |
615 | return -ENODEV; | |
616 | ||
617 | if (mtd->get_device) { | |
3bd45657 ML |
618 | err = mtd->get_device(mtd); |
619 | ||
620 | if (err) { | |
621 | module_put(mtd->owner); | |
622 | return err; | |
623 | } | |
624 | } | |
625 | mtd->usecount++; | |
626 | return 0; | |
1da177e4 LT |
627 | } |
628 | ||
7799308f AB |
629 | /** |
630 | * get_mtd_device_nm - obtain a validated handle for an MTD device by | |
631 | * device name | |
632 | * @name: MTD device name to open | |
633 | * | |
634 | * This function returns MTD device description structure in case of | |
635 | * success and an error code in case of failure. | |
636 | */ | |
637 | ||
638 | struct mtd_info *get_mtd_device_nm(const char *name) | |
639 | { | |
f1332ba2 BH |
640 | int err = -ENODEV; |
641 | struct mtd_info *mtd = NULL, *other; | |
7799308f AB |
642 | |
643 | mutex_lock(&mtd_table_mutex); | |
644 | ||
f1332ba2 BH |
645 | mtd_for_each_device(other) { |
646 | if (!strcmp(name, other->name)) { | |
647 | mtd = other; | |
7799308f AB |
648 | break; |
649 | } | |
650 | } | |
651 | ||
9fe912ce | 652 | if (!mtd) |
7799308f AB |
653 | goto out_unlock; |
654 | ||
52534f2d WG |
655 | err = __get_mtd_device(mtd); |
656 | if (err) | |
7799308f AB |
657 | goto out_unlock; |
658 | ||
9fe912ce AB |
659 | mutex_unlock(&mtd_table_mutex); |
660 | return mtd; | |
7799308f AB |
661 | |
662 | out_unlock: | |
663 | mutex_unlock(&mtd_table_mutex); | |
9fe912ce | 664 | return ERR_PTR(err); |
7799308f AB |
665 | } |
666 | ||
1da177e4 LT |
667 | void put_mtd_device(struct mtd_info *mtd) |
668 | { | |
48b19268 | 669 | mutex_lock(&mtd_table_mutex); |
3bd45657 ML |
670 | __put_mtd_device(mtd); |
671 | mutex_unlock(&mtd_table_mutex); | |
672 | ||
673 | } | |
674 | ||
675 | void __put_mtd_device(struct mtd_info *mtd) | |
676 | { | |
677 | --mtd->usecount; | |
678 | BUG_ON(mtd->usecount < 0); | |
679 | ||
9fe912ce AB |
680 | if (mtd->put_device) |
681 | mtd->put_device(mtd); | |
1da177e4 LT |
682 | |
683 | module_put(mtd->owner); | |
684 | } | |
685 | ||
52b02031 AB |
686 | /* |
687 | * default_mtd_writev - the default writev method | |
688 | * @mtd: mtd device description object pointer | |
689 | * @vecs: the vectors to write | |
690 | * @count: count of vectors in @vecs | |
691 | * @to: the MTD device offset to write to | |
692 | * @retlen: on exit contains the count of bytes written to the MTD device. | |
693 | * | |
694 | * This function returns zero in case of success and a negative error code in | |
695 | * case of failure. | |
1da177e4 | 696 | */ |
1da177e4 LT |
697 | int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs, |
698 | unsigned long count, loff_t to, size_t *retlen) | |
699 | { | |
700 | unsigned long i; | |
701 | size_t totlen = 0, thislen; | |
702 | int ret = 0; | |
703 | ||
52b02031 AB |
704 | for (i = 0; i < count; i++) { |
705 | if (!vecs[i].iov_len) | |
706 | continue; | |
707 | ret = mtd_write(mtd, to, vecs[i].iov_len, &thislen, | |
708 | vecs[i].iov_base); | |
709 | totlen += thislen; | |
710 | if (ret || thislen != vecs[i].iov_len) | |
711 | break; | |
712 | to += vecs[i].iov_len; | |
1da177e4 | 713 | } |
52b02031 | 714 | *retlen = totlen; |
1da177e4 LT |
715 | return ret; |
716 | } | |
717 | ||
33b53716 GE |
718 | /** |
719 | * mtd_kmalloc_up_to - allocate a contiguous buffer up to the specified size | |
52b02031 AB |
720 | * @mtd: mtd device description object pointer |
721 | * @size: a pointer to the ideal or maximum size of the allocation, points | |
33b53716 GE |
722 | * to the actual allocation size on success. |
723 | * | |
724 | * This routine attempts to allocate a contiguous kernel buffer up to | |
725 | * the specified size, backing off the size of the request exponentially | |
726 | * until the request succeeds or until the allocation size falls below | |
727 | * the system page size. This attempts to make sure it does not adversely | |
728 | * impact system performance, so when allocating more than one page, we | |
729 | * ask the memory allocator to avoid re-trying, swapping, writing back | |
730 | * or performing I/O. | |
731 | * | |
732 | * Note, this function also makes sure that the allocated buffer is aligned to | |
733 | * the MTD device's min. I/O unit, i.e. the "mtd->writesize" value. | |
734 | * | |
735 | * This is called, for example by mtd_{read,write} and jffs2_scan_medium, | |
736 | * to handle smaller (i.e. degraded) buffer allocations under low- or | |
737 | * fragmented-memory situations where such reduced allocations, from a | |
738 | * requested ideal, are allowed. | |
739 | * | |
740 | * Returns a pointer to the allocated buffer on success; otherwise, NULL. | |
741 | */ | |
742 | void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size) | |
743 | { | |
744 | gfp_t flags = __GFP_NOWARN | __GFP_WAIT | | |
745 | __GFP_NORETRY | __GFP_NO_KSWAPD; | |
746 | size_t min_alloc = max_t(size_t, mtd->writesize, PAGE_SIZE); | |
747 | void *kbuf; | |
748 | ||
749 | *size = min_t(size_t, *size, KMALLOC_MAX_SIZE); | |
750 | ||
751 | while (*size > min_alloc) { | |
752 | kbuf = kmalloc(*size, flags); | |
753 | if (kbuf) | |
754 | return kbuf; | |
755 | ||
756 | *size >>= 1; | |
757 | *size = ALIGN(*size, mtd->writesize); | |
758 | } | |
759 | ||
760 | /* | |
761 | * For the last resort allocation allow 'kmalloc()' to do all sorts of | |
762 | * things (write-back, dropping caches, etc) by using GFP_KERNEL. | |
763 | */ | |
764 | return kmalloc(*size, GFP_KERNEL); | |
765 | } | |
766 | ||
dd36f267 DW |
767 | EXPORT_SYMBOL_GPL(get_mtd_device); |
768 | EXPORT_SYMBOL_GPL(get_mtd_device_nm); | |
3bd45657 | 769 | EXPORT_SYMBOL_GPL(__get_mtd_device); |
dd36f267 | 770 | EXPORT_SYMBOL_GPL(put_mtd_device); |
3bd45657 | 771 | EXPORT_SYMBOL_GPL(__put_mtd_device); |
dd36f267 DW |
772 | EXPORT_SYMBOL_GPL(register_mtd_user); |
773 | EXPORT_SYMBOL_GPL(unregister_mtd_user); | |
774 | EXPORT_SYMBOL_GPL(default_mtd_writev); | |
33b53716 | 775 | EXPORT_SYMBOL_GPL(mtd_kmalloc_up_to); |
1da177e4 | 776 | |
2d2dce0e PM |
777 | #ifdef CONFIG_PROC_FS |
778 | ||
1da177e4 LT |
779 | /*====================================================================*/ |
780 | /* Support for /proc/mtd */ | |
781 | ||
1da177e4 LT |
782 | static struct proc_dir_entry *proc_mtd; |
783 | ||
447d9bd8 | 784 | static int mtd_proc_show(struct seq_file *m, void *v) |
1da177e4 | 785 | { |
f1332ba2 | 786 | struct mtd_info *mtd; |
1da177e4 | 787 | |
447d9bd8 | 788 | seq_puts(m, "dev: size erasesize name\n"); |
48b19268 | 789 | mutex_lock(&mtd_table_mutex); |
f1332ba2 | 790 | mtd_for_each_device(mtd) { |
447d9bd8 AD |
791 | seq_printf(m, "mtd%d: %8.8llx %8.8x \"%s\"\n", |
792 | mtd->index, (unsigned long long)mtd->size, | |
793 | mtd->erasesize, mtd->name); | |
d5ca5129 | 794 | } |
48b19268 | 795 | mutex_unlock(&mtd_table_mutex); |
d5ca5129 | 796 | return 0; |
1da177e4 LT |
797 | } |
798 | ||
447d9bd8 AD |
799 | static int mtd_proc_open(struct inode *inode, struct file *file) |
800 | { | |
801 | return single_open(file, mtd_proc_show, NULL); | |
802 | } | |
803 | ||
804 | static const struct file_operations mtd_proc_ops = { | |
805 | .open = mtd_proc_open, | |
806 | .read = seq_read, | |
807 | .llseek = seq_lseek, | |
808 | .release = single_release, | |
809 | }; | |
45b09076 KC |
810 | #endif /* CONFIG_PROC_FS */ |
811 | ||
1da177e4 LT |
812 | /*====================================================================*/ |
813 | /* Init code */ | |
814 | ||
0661b1ac JA |
815 | static int __init mtd_bdi_init(struct backing_dev_info *bdi, const char *name) |
816 | { | |
817 | int ret; | |
818 | ||
819 | ret = bdi_init(bdi); | |
820 | if (!ret) | |
821 | ret = bdi_register(bdi, NULL, name); | |
822 | ||
823 | if (ret) | |
824 | bdi_destroy(bdi); | |
825 | ||
826 | return ret; | |
827 | } | |
828 | ||
1da177e4 LT |
829 | static int __init init_mtd(void) |
830 | { | |
15bce40c | 831 | int ret; |
0661b1ac | 832 | |
15bce40c | 833 | ret = class_register(&mtd_class); |
0661b1ac JA |
834 | if (ret) |
835 | goto err_reg; | |
836 | ||
837 | ret = mtd_bdi_init(&mtd_bdi_unmappable, "mtd-unmap"); | |
838 | if (ret) | |
839 | goto err_bdi1; | |
840 | ||
841 | ret = mtd_bdi_init(&mtd_bdi_ro_mappable, "mtd-romap"); | |
842 | if (ret) | |
843 | goto err_bdi2; | |
844 | ||
845 | ret = mtd_bdi_init(&mtd_bdi_rw_mappable, "mtd-rwmap"); | |
846 | if (ret) | |
847 | goto err_bdi3; | |
694bb7fc | 848 | |
45b09076 | 849 | #ifdef CONFIG_PROC_FS |
447d9bd8 | 850 | proc_mtd = proc_create("mtd", 0, NULL, &mtd_proc_ops); |
45b09076 | 851 | #endif /* CONFIG_PROC_FS */ |
1da177e4 | 852 | return 0; |
0661b1ac JA |
853 | |
854 | err_bdi3: | |
855 | bdi_destroy(&mtd_bdi_ro_mappable); | |
856 | err_bdi2: | |
857 | bdi_destroy(&mtd_bdi_unmappable); | |
858 | err_bdi1: | |
859 | class_unregister(&mtd_class); | |
860 | err_reg: | |
861 | pr_err("Error registering mtd class or bdi: %d\n", ret); | |
862 | return ret; | |
1da177e4 LT |
863 | } |
864 | ||
865 | static void __exit cleanup_mtd(void) | |
866 | { | |
45b09076 | 867 | #ifdef CONFIG_PROC_FS |
d5ca5129 | 868 | if (proc_mtd) |
1da177e4 | 869 | remove_proc_entry( "mtd", NULL); |
45b09076 | 870 | #endif /* CONFIG_PROC_FS */ |
15bce40c | 871 | class_unregister(&mtd_class); |
0661b1ac JA |
872 | bdi_destroy(&mtd_bdi_unmappable); |
873 | bdi_destroy(&mtd_bdi_ro_mappable); | |
874 | bdi_destroy(&mtd_bdi_rw_mappable); | |
1da177e4 LT |
875 | } |
876 | ||
877 | module_init(init_mtd); | |
878 | module_exit(cleanup_mtd); | |
879 | ||
1da177e4 LT |
880 | MODULE_LICENSE("GPL"); |
881 | MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>"); | |
882 | MODULE_DESCRIPTION("Core MTD registration and access routines"); |