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