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