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