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Commit | Line | Data |
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1da177e4 | 1 | /* |
97894cda | 2 | * $Id: mtdcore.c,v 1.47 2005/11/07 11:14:20 gleixner Exp $ |
1da177e4 LT |
3 | * |
4 | * Core registration and callback routines for MTD | |
5 | * drivers and users. | |
6 | * | |
7 | */ | |
8 | ||
1da177e4 LT |
9 | #include <linux/module.h> |
10 | #include <linux/kernel.h> | |
1da177e4 LT |
11 | #include <linux/ptrace.h> |
12 | #include <linux/slab.h> | |
13 | #include <linux/string.h> | |
14 | #include <linux/timer.h> | |
15 | #include <linux/major.h> | |
16 | #include <linux/fs.h> | |
7799308f | 17 | #include <linux/err.h> |
1da177e4 LT |
18 | #include <linux/ioctl.h> |
19 | #include <linux/init.h> | |
20 | #include <linux/mtd/compatmac.h> | |
1da177e4 | 21 | #include <linux/proc_fs.h> |
1da177e4 LT |
22 | |
23 | #include <linux/mtd/mtd.h> | |
24 | ||
356d70f1 BD |
25 | #include "mtdcore.h" |
26 | ||
97894cda | 27 | /* These are exported solely for the purpose of mtd_blkdevs.c. You |
1da177e4 | 28 | should not use them for _anything_ else */ |
48b19268 | 29 | DEFINE_MUTEX(mtd_table_mutex); |
1da177e4 LT |
30 | struct mtd_info *mtd_table[MAX_MTD_DEVICES]; |
31 | ||
32 | EXPORT_SYMBOL_GPL(mtd_table_mutex); | |
33 | EXPORT_SYMBOL_GPL(mtd_table); | |
34 | ||
35 | static LIST_HEAD(mtd_notifiers); | |
36 | ||
37 | /** | |
38 | * add_mtd_device - register an MTD device | |
39 | * @mtd: pointer to new MTD device info structure | |
40 | * | |
41 | * Add a device to the list of MTD devices present in the system, and | |
42 | * notify each currently active MTD 'user' of its arrival. Returns | |
43 | * zero on success or 1 on failure, which currently will only happen | |
44 | * if the number of present devices exceeds MAX_MTD_DEVICES (i.e. 16) | |
45 | */ | |
46 | ||
47 | int add_mtd_device(struct mtd_info *mtd) | |
48 | { | |
49 | int i; | |
50 | ||
783ed81f | 51 | BUG_ON(mtd->writesize == 0); |
48b19268 | 52 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
53 | |
54 | for (i=0; i < MAX_MTD_DEVICES; i++) | |
55 | if (!mtd_table[i]) { | |
2606c797 | 56 | struct mtd_notifier *not; |
1da177e4 LT |
57 | |
58 | mtd_table[i] = mtd; | |
59 | mtd->index = i; | |
60 | mtd->usecount = 0; | |
61 | ||
187ef152 HS |
62 | /* Some chips always power up locked. Unlock them now */ |
63 | if ((mtd->flags & MTD_WRITEABLE) | |
e619a75f | 64 | && (mtd->flags & MTD_POWERUP_LOCK) && mtd->unlock) { |
187ef152 HS |
65 | if (mtd->unlock(mtd, 0, mtd->size)) |
66 | printk(KERN_WARNING | |
67 | "%s: unlock failed, " | |
68 | "writes may not work\n", | |
69 | mtd->name); | |
70 | } | |
71 | ||
1da177e4 LT |
72 | DEBUG(0, "mtd: Giving out device %d to %s\n",i, mtd->name); |
73 | /* No need to get a refcount on the module containing | |
74 | the notifier, since we hold the mtd_table_mutex */ | |
2606c797 | 75 | list_for_each_entry(not, &mtd_notifiers, list) { |
1da177e4 LT |
76 | not->add(mtd); |
77 | } | |
97894cda | 78 | |
48b19268 | 79 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
80 | /* We _know_ we aren't being removed, because |
81 | our caller is still holding us here. So none | |
82 | of this try_ nonsense, and no bitching about it | |
83 | either. :) */ | |
84 | __module_get(THIS_MODULE); | |
85 | return 0; | |
86 | } | |
97894cda | 87 | |
48b19268 | 88 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
89 | return 1; |
90 | } | |
91 | ||
92 | /** | |
93 | * del_mtd_device - unregister an MTD device | |
94 | * @mtd: pointer to MTD device info structure | |
95 | * | |
96 | * Remove a device from the list of MTD devices present in the system, | |
97 | * and notify each currently active MTD 'user' of its departure. | |
98 | * Returns zero on success or 1 on failure, which currently will happen | |
99 | * if the requested device does not appear to be present in the list. | |
100 | */ | |
101 | ||
102 | int del_mtd_device (struct mtd_info *mtd) | |
103 | { | |
104 | int ret; | |
97894cda | 105 | |
48b19268 | 106 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
107 | |
108 | if (mtd_table[mtd->index] != mtd) { | |
109 | ret = -ENODEV; | |
110 | } else if (mtd->usecount) { | |
97894cda | 111 | printk(KERN_NOTICE "Removing MTD device #%d (%s) with use count %d\n", |
1da177e4 LT |
112 | mtd->index, mtd->name, mtd->usecount); |
113 | ret = -EBUSY; | |
114 | } else { | |
115 | struct list_head *this; | |
116 | ||
117 | /* No need to get a refcount on the module containing | |
118 | the notifier, since we hold the mtd_table_mutex */ | |
119 | list_for_each(this, &mtd_notifiers) { | |
120 | struct mtd_notifier *not = list_entry(this, struct mtd_notifier, list); | |
121 | not->remove(mtd); | |
122 | } | |
123 | ||
124 | mtd_table[mtd->index] = NULL; | |
125 | ||
126 | module_put(THIS_MODULE); | |
127 | ret = 0; | |
128 | } | |
129 | ||
48b19268 | 130 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
131 | return ret; |
132 | } | |
133 | ||
134 | /** | |
135 | * register_mtd_user - register a 'user' of MTD devices. | |
136 | * @new: pointer to notifier info structure | |
137 | * | |
138 | * Registers a pair of callbacks function to be called upon addition | |
139 | * or removal of MTD devices. Causes the 'add' callback to be immediately | |
140 | * invoked for each MTD device currently present in the system. | |
141 | */ | |
142 | ||
143 | void register_mtd_user (struct mtd_notifier *new) | |
144 | { | |
145 | int i; | |
146 | ||
48b19268 | 147 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
148 | |
149 | list_add(&new->list, &mtd_notifiers); | |
150 | ||
151 | __module_get(THIS_MODULE); | |
97894cda | 152 | |
1da177e4 LT |
153 | for (i=0; i< MAX_MTD_DEVICES; i++) |
154 | if (mtd_table[i]) | |
155 | new->add(mtd_table[i]); | |
156 | ||
48b19268 | 157 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
158 | } |
159 | ||
160 | /** | |
49450795 AB |
161 | * unregister_mtd_user - unregister a 'user' of MTD devices. |
162 | * @old: pointer to notifier info structure | |
1da177e4 LT |
163 | * |
164 | * Removes a callback function pair from the list of 'users' to be | |
165 | * notified upon addition or removal of MTD devices. Causes the | |
166 | * 'remove' callback to be immediately invoked for each MTD device | |
167 | * currently present in the system. | |
168 | */ | |
169 | ||
170 | int unregister_mtd_user (struct mtd_notifier *old) | |
171 | { | |
172 | int i; | |
173 | ||
48b19268 | 174 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
175 | |
176 | module_put(THIS_MODULE); | |
177 | ||
178 | for (i=0; i< MAX_MTD_DEVICES; i++) | |
179 | if (mtd_table[i]) | |
180 | old->remove(mtd_table[i]); | |
97894cda | 181 | |
1da177e4 | 182 | list_del(&old->list); |
48b19268 | 183 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
184 | return 0; |
185 | } | |
186 | ||
187 | ||
188 | /** | |
189 | * get_mtd_device - obtain a validated handle for an MTD device | |
190 | * @mtd: last known address of the required MTD device | |
191 | * @num: internal device number of the required MTD device | |
192 | * | |
193 | * Given a number and NULL address, return the num'th entry in the device | |
194 | * table, if any. Given an address and num == -1, search the device table | |
195 | * for a device with that address and return if it's still present. Given | |
9c74034f AB |
196 | * both, return the num'th driver only if its address matches. Return |
197 | * error code if not. | |
1da177e4 | 198 | */ |
97894cda | 199 | |
1da177e4 LT |
200 | struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num) |
201 | { | |
202 | struct mtd_info *ret = NULL; | |
9c74034f | 203 | int i, err = -ENODEV; |
1da177e4 | 204 | |
48b19268 | 205 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
206 | |
207 | if (num == -1) { | |
208 | for (i=0; i< MAX_MTD_DEVICES; i++) | |
209 | if (mtd_table[i] == mtd) | |
210 | ret = mtd_table[i]; | |
211 | } else if (num < MAX_MTD_DEVICES) { | |
212 | ret = mtd_table[num]; | |
213 | if (mtd && mtd != ret) | |
214 | ret = NULL; | |
215 | } | |
216 | ||
9fe912ce AB |
217 | if (!ret) |
218 | goto out_unlock; | |
219 | ||
9c74034f | 220 | if (!try_module_get(ret->owner)) |
9fe912ce | 221 | goto out_unlock; |
9fe912ce | 222 | |
9c74034f AB |
223 | if (ret->get_device) { |
224 | err = ret->get_device(ret); | |
225 | if (err) | |
226 | goto out_put; | |
9fe912ce | 227 | } |
1da177e4 | 228 | |
9fe912ce | 229 | ret->usecount++; |
9c74034f AB |
230 | mutex_unlock(&mtd_table_mutex); |
231 | return ret; | |
1da177e4 | 232 | |
9c74034f AB |
233 | out_put: |
234 | module_put(ret->owner); | |
9fe912ce | 235 | out_unlock: |
48b19268 | 236 | mutex_unlock(&mtd_table_mutex); |
9c74034f | 237 | return ERR_PTR(err); |
1da177e4 LT |
238 | } |
239 | ||
7799308f AB |
240 | /** |
241 | * get_mtd_device_nm - obtain a validated handle for an MTD device by | |
242 | * device name | |
243 | * @name: MTD device name to open | |
244 | * | |
245 | * This function returns MTD device description structure in case of | |
246 | * success and an error code in case of failure. | |
247 | */ | |
248 | ||
249 | struct mtd_info *get_mtd_device_nm(const char *name) | |
250 | { | |
9fe912ce AB |
251 | int i, err = -ENODEV; |
252 | struct mtd_info *mtd = NULL; | |
7799308f AB |
253 | |
254 | mutex_lock(&mtd_table_mutex); | |
255 | ||
256 | for (i = 0; i < MAX_MTD_DEVICES; i++) { | |
257 | if (mtd_table[i] && !strcmp(name, mtd_table[i]->name)) { | |
258 | mtd = mtd_table[i]; | |
259 | break; | |
260 | } | |
261 | } | |
262 | ||
9fe912ce | 263 | if (!mtd) |
7799308f AB |
264 | goto out_unlock; |
265 | ||
266 | if (!try_module_get(mtd->owner)) | |
267 | goto out_unlock; | |
268 | ||
9fe912ce AB |
269 | if (mtd->get_device) { |
270 | err = mtd->get_device(mtd); | |
271 | if (err) | |
272 | goto out_put; | |
273 | } | |
274 | ||
7799308f | 275 | mtd->usecount++; |
9fe912ce AB |
276 | mutex_unlock(&mtd_table_mutex); |
277 | return mtd; | |
7799308f | 278 | |
9fe912ce AB |
279 | out_put: |
280 | module_put(mtd->owner); | |
7799308f AB |
281 | out_unlock: |
282 | mutex_unlock(&mtd_table_mutex); | |
9fe912ce | 283 | return ERR_PTR(err); |
7799308f AB |
284 | } |
285 | ||
1da177e4 LT |
286 | void put_mtd_device(struct mtd_info *mtd) |
287 | { | |
288 | int c; | |
289 | ||
48b19268 | 290 | mutex_lock(&mtd_table_mutex); |
1da177e4 | 291 | c = --mtd->usecount; |
9fe912ce AB |
292 | if (mtd->put_device) |
293 | mtd->put_device(mtd); | |
48b19268 | 294 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
295 | BUG_ON(c < 0); |
296 | ||
297 | module_put(mtd->owner); | |
298 | } | |
299 | ||
300 | /* default_mtd_writev - default mtd writev method for MTD devices that | |
dd36f267 | 301 | * don't implement their own |
1da177e4 LT |
302 | */ |
303 | ||
304 | int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs, | |
305 | unsigned long count, loff_t to, size_t *retlen) | |
306 | { | |
307 | unsigned long i; | |
308 | size_t totlen = 0, thislen; | |
309 | int ret = 0; | |
310 | ||
311 | if(!mtd->write) { | |
312 | ret = -EROFS; | |
313 | } else { | |
314 | for (i=0; i<count; i++) { | |
315 | if (!vecs[i].iov_len) | |
316 | continue; | |
317 | ret = mtd->write(mtd, to, vecs[i].iov_len, &thislen, vecs[i].iov_base); | |
318 | totlen += thislen; | |
319 | if (ret || thislen != vecs[i].iov_len) | |
320 | break; | |
321 | to += vecs[i].iov_len; | |
322 | } | |
323 | } | |
324 | if (retlen) | |
325 | *retlen = totlen; | |
326 | return ret; | |
327 | } | |
328 | ||
dd36f267 DW |
329 | EXPORT_SYMBOL_GPL(add_mtd_device); |
330 | EXPORT_SYMBOL_GPL(del_mtd_device); | |
331 | EXPORT_SYMBOL_GPL(get_mtd_device); | |
332 | EXPORT_SYMBOL_GPL(get_mtd_device_nm); | |
333 | EXPORT_SYMBOL_GPL(put_mtd_device); | |
334 | EXPORT_SYMBOL_GPL(register_mtd_user); | |
335 | EXPORT_SYMBOL_GPL(unregister_mtd_user); | |
336 | EXPORT_SYMBOL_GPL(default_mtd_writev); | |
1da177e4 | 337 | |
2d2dce0e PM |
338 | #ifdef CONFIG_PROC_FS |
339 | ||
1da177e4 LT |
340 | /*====================================================================*/ |
341 | /* Support for /proc/mtd */ | |
342 | ||
1da177e4 LT |
343 | static struct proc_dir_entry *proc_mtd; |
344 | ||
345 | static inline int mtd_proc_info (char *buf, int i) | |
346 | { | |
347 | struct mtd_info *this = mtd_table[i]; | |
348 | ||
349 | if (!this) | |
350 | return 0; | |
351 | ||
352 | return sprintf(buf, "mtd%d: %8.8x %8.8x \"%s\"\n", i, this->size, | |
353 | this->erasesize, this->name); | |
354 | } | |
355 | ||
356 | static int mtd_read_proc (char *page, char **start, off_t off, int count, | |
357 | int *eof, void *data_unused) | |
358 | { | |
359 | int len, l, i; | |
360 | off_t begin = 0; | |
361 | ||
48b19268 | 362 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
363 | |
364 | len = sprintf(page, "dev: size erasesize name\n"); | |
365 | for (i=0; i< MAX_MTD_DEVICES; i++) { | |
366 | ||
367 | l = mtd_proc_info(page + len, i); | |
368 | len += l; | |
369 | if (len+begin > off+count) | |
370 | goto done; | |
371 | if (len+begin < off) { | |
372 | begin += len; | |
373 | len = 0; | |
374 | } | |
375 | } | |
376 | ||
377 | *eof = 1; | |
378 | ||
379 | done: | |
48b19268 | 380 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
381 | if (off >= len+begin) |
382 | return 0; | |
383 | *start = page + (off-begin); | |
384 | return ((count < begin+len-off) ? count : begin+len-off); | |
385 | } | |
386 | ||
1da177e4 LT |
387 | /*====================================================================*/ |
388 | /* Init code */ | |
389 | ||
390 | static int __init init_mtd(void) | |
391 | { | |
1da177e4 LT |
392 | if ((proc_mtd = create_proc_entry( "mtd", 0, NULL ))) |
393 | proc_mtd->read_proc = mtd_read_proc; | |
1da177e4 LT |
394 | return 0; |
395 | } | |
396 | ||
397 | static void __exit cleanup_mtd(void) | |
398 | { | |
1da177e4 LT |
399 | if (proc_mtd) |
400 | remove_proc_entry( "mtd", NULL); | |
1da177e4 LT |
401 | } |
402 | ||
403 | module_init(init_mtd); | |
404 | module_exit(cleanup_mtd); | |
405 | ||
2d2dce0e PM |
406 | #endif /* CONFIG_PROC_FS */ |
407 | ||
1da177e4 LT |
408 | |
409 | MODULE_LICENSE("GPL"); | |
410 | MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>"); | |
411 | MODULE_DESCRIPTION("Core MTD registration and access routines"); |