Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
1da177e4 LT |
2 | * Core registration and callback routines for MTD |
3 | * drivers and users. | |
4 | * | |
5 | */ | |
6 | ||
1da177e4 LT |
7 | #include <linux/module.h> |
8 | #include <linux/kernel.h> | |
1da177e4 LT |
9 | #include <linux/ptrace.h> |
10 | #include <linux/slab.h> | |
11 | #include <linux/string.h> | |
12 | #include <linux/timer.h> | |
13 | #include <linux/major.h> | |
14 | #include <linux/fs.h> | |
7799308f | 15 | #include <linux/err.h> |
1da177e4 LT |
16 | #include <linux/ioctl.h> |
17 | #include <linux/init.h> | |
18 | #include <linux/mtd/compatmac.h> | |
1da177e4 | 19 | #include <linux/proc_fs.h> |
1da177e4 LT |
20 | |
21 | #include <linux/mtd/mtd.h> | |
22 | ||
356d70f1 BD |
23 | #include "mtdcore.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]) { | |
2606c797 | 54 | struct mtd_notifier *not; |
1da177e4 LT |
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) | |
e619a75f | 62 | && (mtd->flags & MTD_POWERUP_LOCK) && mtd->unlock) { |
187ef152 HS |
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 */ | |
71a928c0 | 73 | list_for_each_entry(not, &mtd_notifiers, list) |
1da177e4 | 74 | not->add(mtd); |
97894cda | 75 | |
48b19268 | 76 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
77 | /* We _know_ we aren't being removed, because |
78 | our caller is still holding us here. So none | |
79 | of this try_ nonsense, and no bitching about it | |
80 | either. :) */ | |
81 | __module_get(THIS_MODULE); | |
82 | return 0; | |
83 | } | |
97894cda | 84 | |
48b19268 | 85 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
86 | return 1; |
87 | } | |
88 | ||
89 | /** | |
90 | * del_mtd_device - unregister an MTD device | |
91 | * @mtd: pointer to MTD device info structure | |
92 | * | |
93 | * Remove a device from the list of MTD devices present in the system, | |
94 | * and notify each currently active MTD 'user' of its departure. | |
95 | * Returns zero on success or 1 on failure, which currently will happen | |
96 | * if the requested device does not appear to be present in the list. | |
97 | */ | |
98 | ||
99 | int del_mtd_device (struct mtd_info *mtd) | |
100 | { | |
101 | int ret; | |
97894cda | 102 | |
48b19268 | 103 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
104 | |
105 | if (mtd_table[mtd->index] != mtd) { | |
106 | ret = -ENODEV; | |
107 | } else if (mtd->usecount) { | |
97894cda | 108 | printk(KERN_NOTICE "Removing MTD device #%d (%s) with use count %d\n", |
1da177e4 LT |
109 | mtd->index, mtd->name, mtd->usecount); |
110 | ret = -EBUSY; | |
111 | } else { | |
856613c9 | 112 | struct mtd_notifier *not; |
1da177e4 LT |
113 | |
114 | /* No need to get a refcount on the module containing | |
115 | the notifier, since we hold the mtd_table_mutex */ | |
71a928c0 | 116 | list_for_each_entry(not, &mtd_notifiers, list) |
1da177e4 | 117 | not->remove(mtd); |
1da177e4 LT |
118 | |
119 | mtd_table[mtd->index] = NULL; | |
120 | ||
121 | module_put(THIS_MODULE); | |
122 | ret = 0; | |
123 | } | |
124 | ||
48b19268 | 125 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
126 | return ret; |
127 | } | |
128 | ||
129 | /** | |
130 | * register_mtd_user - register a 'user' of MTD devices. | |
131 | * @new: pointer to notifier info structure | |
132 | * | |
133 | * Registers a pair of callbacks function to be called upon addition | |
134 | * or removal of MTD devices. Causes the 'add' callback to be immediately | |
135 | * invoked for each MTD device currently present in the system. | |
136 | */ | |
137 | ||
138 | void register_mtd_user (struct mtd_notifier *new) | |
139 | { | |
140 | int i; | |
141 | ||
48b19268 | 142 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
143 | |
144 | list_add(&new->list, &mtd_notifiers); | |
145 | ||
146 | __module_get(THIS_MODULE); | |
97894cda | 147 | |
1da177e4 LT |
148 | for (i=0; i< MAX_MTD_DEVICES; i++) |
149 | if (mtd_table[i]) | |
150 | new->add(mtd_table[i]); | |
151 | ||
48b19268 | 152 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
153 | } |
154 | ||
155 | /** | |
49450795 AB |
156 | * unregister_mtd_user - unregister a 'user' of MTD devices. |
157 | * @old: pointer to notifier info structure | |
1da177e4 LT |
158 | * |
159 | * Removes a callback function pair from the list of 'users' to be | |
160 | * notified upon addition or removal of MTD devices. Causes the | |
161 | * 'remove' callback to be immediately invoked for each MTD device | |
162 | * currently present in the system. | |
163 | */ | |
164 | ||
165 | int unregister_mtd_user (struct mtd_notifier *old) | |
166 | { | |
167 | int i; | |
168 | ||
48b19268 | 169 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
170 | |
171 | module_put(THIS_MODULE); | |
172 | ||
173 | for (i=0; i< MAX_MTD_DEVICES; i++) | |
174 | if (mtd_table[i]) | |
175 | old->remove(mtd_table[i]); | |
97894cda | 176 | |
1da177e4 | 177 | list_del(&old->list); |
48b19268 | 178 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
179 | return 0; |
180 | } | |
181 | ||
182 | ||
183 | /** | |
184 | * get_mtd_device - obtain a validated handle for an MTD device | |
185 | * @mtd: last known address of the required MTD device | |
186 | * @num: internal device number of the required MTD device | |
187 | * | |
188 | * Given a number and NULL address, return the num'th entry in the device | |
189 | * table, if any. Given an address and num == -1, search the device table | |
190 | * for a device with that address and return if it's still present. Given | |
9c74034f AB |
191 | * both, return the num'th driver only if its address matches. Return |
192 | * error code if not. | |
1da177e4 | 193 | */ |
97894cda | 194 | |
1da177e4 LT |
195 | struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num) |
196 | { | |
197 | struct mtd_info *ret = NULL; | |
9c74034f | 198 | int i, err = -ENODEV; |
1da177e4 | 199 | |
48b19268 | 200 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
201 | |
202 | if (num == -1) { | |
203 | for (i=0; i< MAX_MTD_DEVICES; i++) | |
204 | if (mtd_table[i] == mtd) | |
205 | ret = mtd_table[i]; | |
206 | } else if (num < MAX_MTD_DEVICES) { | |
207 | ret = mtd_table[num]; | |
208 | if (mtd && mtd != ret) | |
209 | ret = NULL; | |
210 | } | |
211 | ||
9fe912ce AB |
212 | if (!ret) |
213 | goto out_unlock; | |
214 | ||
9c74034f | 215 | if (!try_module_get(ret->owner)) |
9fe912ce | 216 | goto out_unlock; |
9fe912ce | 217 | |
9c74034f AB |
218 | if (ret->get_device) { |
219 | err = ret->get_device(ret); | |
220 | if (err) | |
221 | goto out_put; | |
9fe912ce | 222 | } |
1da177e4 | 223 | |
9fe912ce | 224 | ret->usecount++; |
9c74034f AB |
225 | mutex_unlock(&mtd_table_mutex); |
226 | return ret; | |
1da177e4 | 227 | |
9c74034f AB |
228 | out_put: |
229 | module_put(ret->owner); | |
9fe912ce | 230 | out_unlock: |
48b19268 | 231 | mutex_unlock(&mtd_table_mutex); |
9c74034f | 232 | return ERR_PTR(err); |
1da177e4 LT |
233 | } |
234 | ||
7799308f AB |
235 | /** |
236 | * get_mtd_device_nm - obtain a validated handle for an MTD device by | |
237 | * device name | |
238 | * @name: MTD device name to open | |
239 | * | |
240 | * This function returns MTD device description structure in case of | |
241 | * success and an error code in case of failure. | |
242 | */ | |
243 | ||
244 | struct mtd_info *get_mtd_device_nm(const char *name) | |
245 | { | |
9fe912ce AB |
246 | int i, err = -ENODEV; |
247 | struct mtd_info *mtd = NULL; | |
7799308f AB |
248 | |
249 | mutex_lock(&mtd_table_mutex); | |
250 | ||
251 | for (i = 0; i < MAX_MTD_DEVICES; i++) { | |
252 | if (mtd_table[i] && !strcmp(name, mtd_table[i]->name)) { | |
253 | mtd = mtd_table[i]; | |
254 | break; | |
255 | } | |
256 | } | |
257 | ||
9fe912ce | 258 | if (!mtd) |
7799308f AB |
259 | goto out_unlock; |
260 | ||
261 | if (!try_module_get(mtd->owner)) | |
262 | goto out_unlock; | |
263 | ||
9fe912ce AB |
264 | if (mtd->get_device) { |
265 | err = mtd->get_device(mtd); | |
266 | if (err) | |
267 | goto out_put; | |
268 | } | |
269 | ||
7799308f | 270 | mtd->usecount++; |
9fe912ce AB |
271 | mutex_unlock(&mtd_table_mutex); |
272 | return mtd; | |
7799308f | 273 | |
9fe912ce AB |
274 | out_put: |
275 | module_put(mtd->owner); | |
7799308f AB |
276 | out_unlock: |
277 | mutex_unlock(&mtd_table_mutex); | |
9fe912ce | 278 | return ERR_PTR(err); |
7799308f AB |
279 | } |
280 | ||
1da177e4 LT |
281 | void put_mtd_device(struct mtd_info *mtd) |
282 | { | |
283 | int c; | |
284 | ||
48b19268 | 285 | mutex_lock(&mtd_table_mutex); |
1da177e4 | 286 | c = --mtd->usecount; |
9fe912ce AB |
287 | if (mtd->put_device) |
288 | mtd->put_device(mtd); | |
48b19268 | 289 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
290 | BUG_ON(c < 0); |
291 | ||
292 | module_put(mtd->owner); | |
293 | } | |
294 | ||
295 | /* default_mtd_writev - default mtd writev method for MTD devices that | |
dd36f267 | 296 | * don't implement their own |
1da177e4 LT |
297 | */ |
298 | ||
299 | int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs, | |
300 | unsigned long count, loff_t to, size_t *retlen) | |
301 | { | |
302 | unsigned long i; | |
303 | size_t totlen = 0, thislen; | |
304 | int ret = 0; | |
305 | ||
306 | if(!mtd->write) { | |
307 | ret = -EROFS; | |
308 | } else { | |
309 | for (i=0; i<count; i++) { | |
310 | if (!vecs[i].iov_len) | |
311 | continue; | |
312 | ret = mtd->write(mtd, to, vecs[i].iov_len, &thislen, vecs[i].iov_base); | |
313 | totlen += thislen; | |
314 | if (ret || thislen != vecs[i].iov_len) | |
315 | break; | |
316 | to += vecs[i].iov_len; | |
317 | } | |
318 | } | |
319 | if (retlen) | |
320 | *retlen = totlen; | |
321 | return ret; | |
322 | } | |
323 | ||
dd36f267 DW |
324 | EXPORT_SYMBOL_GPL(add_mtd_device); |
325 | EXPORT_SYMBOL_GPL(del_mtd_device); | |
326 | EXPORT_SYMBOL_GPL(get_mtd_device); | |
327 | EXPORT_SYMBOL_GPL(get_mtd_device_nm); | |
328 | EXPORT_SYMBOL_GPL(put_mtd_device); | |
329 | EXPORT_SYMBOL_GPL(register_mtd_user); | |
330 | EXPORT_SYMBOL_GPL(unregister_mtd_user); | |
331 | EXPORT_SYMBOL_GPL(default_mtd_writev); | |
1da177e4 | 332 | |
2d2dce0e PM |
333 | #ifdef CONFIG_PROC_FS |
334 | ||
1da177e4 LT |
335 | /*====================================================================*/ |
336 | /* Support for /proc/mtd */ | |
337 | ||
1da177e4 LT |
338 | static struct proc_dir_entry *proc_mtd; |
339 | ||
340 | static inline int mtd_proc_info (char *buf, int i) | |
341 | { | |
342 | struct mtd_info *this = mtd_table[i]; | |
343 | ||
344 | if (!this) | |
345 | return 0; | |
346 | ||
347 | return sprintf(buf, "mtd%d: %8.8x %8.8x \"%s\"\n", i, this->size, | |
348 | this->erasesize, this->name); | |
349 | } | |
350 | ||
351 | static int mtd_read_proc (char *page, char **start, off_t off, int count, | |
352 | int *eof, void *data_unused) | |
353 | { | |
354 | int len, l, i; | |
355 | off_t begin = 0; | |
356 | ||
48b19268 | 357 | mutex_lock(&mtd_table_mutex); |
1da177e4 LT |
358 | |
359 | len = sprintf(page, "dev: size erasesize name\n"); | |
360 | for (i=0; i< MAX_MTD_DEVICES; i++) { | |
361 | ||
362 | l = mtd_proc_info(page + len, i); | |
363 | len += l; | |
364 | if (len+begin > off+count) | |
365 | goto done; | |
366 | if (len+begin < off) { | |
367 | begin += len; | |
368 | len = 0; | |
369 | } | |
370 | } | |
371 | ||
372 | *eof = 1; | |
373 | ||
374 | done: | |
48b19268 | 375 | mutex_unlock(&mtd_table_mutex); |
1da177e4 LT |
376 | if (off >= len+begin) |
377 | return 0; | |
378 | *start = page + (off-begin); | |
379 | return ((count < begin+len-off) ? count : begin+len-off); | |
380 | } | |
381 | ||
1da177e4 LT |
382 | /*====================================================================*/ |
383 | /* Init code */ | |
384 | ||
385 | static int __init init_mtd(void) | |
386 | { | |
1da177e4 LT |
387 | if ((proc_mtd = create_proc_entry( "mtd", 0, NULL ))) |
388 | proc_mtd->read_proc = mtd_read_proc; | |
1da177e4 LT |
389 | return 0; |
390 | } | |
391 | ||
392 | static void __exit cleanup_mtd(void) | |
393 | { | |
1da177e4 LT |
394 | if (proc_mtd) |
395 | remove_proc_entry( "mtd", NULL); | |
1da177e4 LT |
396 | } |
397 | ||
398 | module_init(init_mtd); | |
399 | module_exit(cleanup_mtd); | |
400 | ||
2d2dce0e PM |
401 | #endif /* CONFIG_PROC_FS */ |
402 | ||
1da177e4 LT |
403 | |
404 | MODULE_LICENSE("GPL"); | |
405 | MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>"); | |
406 | MODULE_DESCRIPTION("Core MTD registration and access routines"); |