Commit | Line | Data |
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4b23aff0 RP |
1 | /* |
2 | * MTD Oops/Panic logger | |
3 | * | |
4 | * Copyright (C) 2007 Nokia Corporation. All rights reserved. | |
5 | * | |
6 | * Author: Richard Purdie <rpurdie@openedhand.com> | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or | |
9 | * modify it under the terms of the GNU General Public License | |
10 | * version 2 as published by the Free Software Foundation. | |
11 | * | |
12 | * This program is distributed in the hope that it will be useful, but | |
13 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
15 | * General Public License for more details. | |
16 | * | |
17 | * You should have received a copy of the GNU General Public License | |
18 | * along with this program; if not, write to the Free Software | |
19 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA | |
20 | * 02110-1301 USA | |
21 | * | |
22 | */ | |
23 | ||
24 | #include <linux/kernel.h> | |
25 | #include <linux/module.h> | |
26 | #include <linux/console.h> | |
27 | #include <linux/vmalloc.h> | |
28 | #include <linux/workqueue.h> | |
29 | #include <linux/sched.h> | |
30 | #include <linux/wait.h> | |
621e4f8e | 31 | #include <linux/delay.h> |
47c152b8 | 32 | #include <linux/spinlock.h> |
f9f7dd22 | 33 | #include <linux/interrupt.h> |
4b23aff0 RP |
34 | #include <linux/mtd/mtd.h> |
35 | ||
f0482ee3 | 36 | #define MTDOOPS_KERNMSG_MAGIC 0x5d005d00 |
4b23aff0 RP |
37 | #define OOPS_PAGE_SIZE 4096 |
38 | ||
7903cbab | 39 | static struct mtdoops_context { |
4b23aff0 | 40 | int mtd_index; |
6ce0a856 RP |
41 | struct work_struct work_erase; |
42 | struct work_struct work_write; | |
4b23aff0 RP |
43 | struct mtd_info *mtd; |
44 | int oops_pages; | |
45 | int nextpage; | |
46 | int nextcount; | |
47 | ||
48 | void *oops_buf; | |
47c152b8 RP |
49 | |
50 | /* writecount and disabling ready are spin lock protected */ | |
51 | spinlock_t writecount_lock; | |
4b23aff0 RP |
52 | int ready; |
53 | int writecount; | |
54 | } oops_cxt; | |
55 | ||
56 | static void mtdoops_erase_callback(struct erase_info *done) | |
57 | { | |
58 | wait_queue_head_t *wait_q = (wait_queue_head_t *)done->priv; | |
59 | wake_up(wait_q); | |
60 | } | |
61 | ||
62 | static int mtdoops_erase_block(struct mtd_info *mtd, int offset) | |
63 | { | |
64 | struct erase_info erase; | |
65 | DECLARE_WAITQUEUE(wait, current); | |
66 | wait_queue_head_t wait_q; | |
67 | int ret; | |
68 | ||
69 | init_waitqueue_head(&wait_q); | |
70 | erase.mtd = mtd; | |
71 | erase.callback = mtdoops_erase_callback; | |
72 | erase.addr = offset; | |
79dcd8e9 | 73 | erase.len = mtd->erasesize; |
4b23aff0 RP |
74 | erase.priv = (u_long)&wait_q; |
75 | ||
76 | set_current_state(TASK_INTERRUPTIBLE); | |
77 | add_wait_queue(&wait_q, &wait); | |
78 | ||
79 | ret = mtd->erase(mtd, &erase); | |
80 | if (ret) { | |
81 | set_current_state(TASK_RUNNING); | |
82 | remove_wait_queue(&wait_q, &wait); | |
83 | printk (KERN_WARNING "mtdoops: erase of region [0x%x, 0x%x] " | |
84 | "on \"%s\" failed\n", | |
85 | erase.addr, erase.len, mtd->name); | |
86 | return ret; | |
87 | } | |
88 | ||
89 | schedule(); /* Wait for erase to finish. */ | |
90 | remove_wait_queue(&wait_q, &wait); | |
91 | ||
92 | return 0; | |
93 | } | |
94 | ||
6ce0a856 | 95 | static void mtdoops_inc_counter(struct mtdoops_context *cxt) |
4b23aff0 RP |
96 | { |
97 | struct mtd_info *mtd = cxt->mtd; | |
98 | size_t retlen; | |
99 | u32 count; | |
100 | int ret; | |
101 | ||
102 | cxt->nextpage++; | |
ecd5b310 | 103 | if (cxt->nextpage >= cxt->oops_pages) |
4b23aff0 RP |
104 | cxt->nextpage = 0; |
105 | cxt->nextcount++; | |
106 | if (cxt->nextcount == 0xffffffff) | |
107 | cxt->nextcount = 0; | |
108 | ||
109 | ret = mtd->read(mtd, cxt->nextpage * OOPS_PAGE_SIZE, 4, | |
110 | &retlen, (u_char *) &count); | |
2986bd2a | 111 | if ((retlen != 4) || ((ret < 0) && (ret != -EUCLEAN))) { |
68d09b1b | 112 | printk(KERN_ERR "mtdoops: Read failure at %d (%td of 4 read)" |
4b23aff0 RP |
113 | ", err %d.\n", cxt->nextpage * OOPS_PAGE_SIZE, |
114 | retlen, ret); | |
6ce0a856 RP |
115 | schedule_work(&cxt->work_erase); |
116 | return; | |
4b23aff0 RP |
117 | } |
118 | ||
119 | /* See if we need to erase the next block */ | |
6ce0a856 RP |
120 | if (count != 0xffffffff) { |
121 | schedule_work(&cxt->work_erase); | |
122 | return; | |
123 | } | |
4b23aff0 RP |
124 | |
125 | printk(KERN_DEBUG "mtdoops: Ready %d, %d (no erase)\n", | |
126 | cxt->nextpage, cxt->nextcount); | |
127 | cxt->ready = 1; | |
4b23aff0 RP |
128 | } |
129 | ||
6ce0a856 RP |
130 | /* Scheduled work - when we can't proceed without erasing a block */ |
131 | static void mtdoops_workfunc_erase(struct work_struct *work) | |
4b23aff0 | 132 | { |
6ce0a856 RP |
133 | struct mtdoops_context *cxt = |
134 | container_of(work, struct mtdoops_context, work_erase); | |
4b23aff0 RP |
135 | struct mtd_info *mtd = cxt->mtd; |
136 | int i = 0, j, ret, mod; | |
137 | ||
138 | /* We were unregistered */ | |
139 | if (!mtd) | |
140 | return; | |
141 | ||
142 | mod = (cxt->nextpage * OOPS_PAGE_SIZE) % mtd->erasesize; | |
143 | if (mod != 0) { | |
144 | cxt->nextpage = cxt->nextpage + ((mtd->erasesize - mod) / OOPS_PAGE_SIZE); | |
ecd5b310 | 145 | if (cxt->nextpage >= cxt->oops_pages) |
4b23aff0 RP |
146 | cxt->nextpage = 0; |
147 | } | |
148 | ||
2986bd2a RP |
149 | while (mtd->block_isbad) { |
150 | ret = mtd->block_isbad(mtd, cxt->nextpage * OOPS_PAGE_SIZE); | |
151 | if (!ret) | |
152 | break; | |
153 | if (ret < 0) { | |
154 | printk(KERN_ERR "mtdoops: block_isbad failed, aborting.\n"); | |
155 | return; | |
156 | } | |
4b23aff0 RP |
157 | badblock: |
158 | printk(KERN_WARNING "mtdoops: Bad block at %08x\n", | |
159 | cxt->nextpage * OOPS_PAGE_SIZE); | |
160 | i++; | |
161 | cxt->nextpage = cxt->nextpage + (mtd->erasesize / OOPS_PAGE_SIZE); | |
ecd5b310 | 162 | if (cxt->nextpage >= cxt->oops_pages) |
4b23aff0 RP |
163 | cxt->nextpage = 0; |
164 | if (i == (cxt->oops_pages / (mtd->erasesize / OOPS_PAGE_SIZE))) { | |
165 | printk(KERN_ERR "mtdoops: All blocks bad!\n"); | |
166 | return; | |
167 | } | |
168 | } | |
169 | ||
170 | for (j = 0, ret = -1; (j < 3) && (ret < 0); j++) | |
171 | ret = mtdoops_erase_block(mtd, cxt->nextpage * OOPS_PAGE_SIZE); | |
172 | ||
2986bd2a RP |
173 | if (ret >= 0) { |
174 | printk(KERN_DEBUG "mtdoops: Ready %d, %d \n", cxt->nextpage, cxt->nextcount); | |
175 | cxt->ready = 1; | |
176 | return; | |
4b23aff0 RP |
177 | } |
178 | ||
2986bd2a RP |
179 | if (mtd->block_markbad && (ret == -EIO)) { |
180 | ret = mtd->block_markbad(mtd, cxt->nextpage * OOPS_PAGE_SIZE); | |
181 | if (ret < 0) { | |
182 | printk(KERN_ERR "mtdoops: block_markbad failed, aborting.\n"); | |
183 | return; | |
184 | } | |
185 | } | |
186 | goto badblock; | |
4b23aff0 RP |
187 | } |
188 | ||
621e4f8e | 189 | static void mtdoops_write(struct mtdoops_context *cxt, int panic) |
4b23aff0 | 190 | { |
6ce0a856 RP |
191 | struct mtd_info *mtd = cxt->mtd; |
192 | size_t retlen; | |
193 | int ret; | |
4b23aff0 | 194 | |
6ce0a856 RP |
195 | if (cxt->writecount < OOPS_PAGE_SIZE) |
196 | memset(cxt->oops_buf + cxt->writecount, 0xff, | |
197 | OOPS_PAGE_SIZE - cxt->writecount); | |
198 | ||
621e4f8e RP |
199 | if (panic) |
200 | ret = mtd->panic_write(mtd, cxt->nextpage * OOPS_PAGE_SIZE, | |
201 | OOPS_PAGE_SIZE, &retlen, cxt->oops_buf); | |
202 | else | |
203 | ret = mtd->write(mtd, cxt->nextpage * OOPS_PAGE_SIZE, | |
6ce0a856 RP |
204 | OOPS_PAGE_SIZE, &retlen, cxt->oops_buf); |
205 | ||
206 | cxt->writecount = 0; | |
207 | ||
208 | if ((retlen != OOPS_PAGE_SIZE) || (ret < 0)) | |
209 | printk(KERN_ERR "mtdoops: Write failure at %d (%td of %d written), err %d.\n", | |
210 | cxt->nextpage * OOPS_PAGE_SIZE, retlen, OOPS_PAGE_SIZE, ret); | |
211 | ||
212 | mtdoops_inc_counter(cxt); | |
621e4f8e RP |
213 | } |
214 | ||
215 | ||
216 | static void mtdoops_workfunc_write(struct work_struct *work) | |
217 | { | |
218 | struct mtdoops_context *cxt = | |
219 | container_of(work, struct mtdoops_context, work_write); | |
220 | ||
221 | mtdoops_write(cxt, 0); | |
6ce0a856 | 222 | } |
4b23aff0 | 223 | |
6ce0a856 | 224 | static void find_next_position(struct mtdoops_context *cxt) |
4b23aff0 RP |
225 | { |
226 | struct mtd_info *mtd = cxt->mtd; | |
2986bd2a | 227 | int ret, page, maxpos = 0; |
f0482ee3 | 228 | u32 count[2], maxcount = 0xffffffff; |
4b23aff0 RP |
229 | size_t retlen; |
230 | ||
231 | for (page = 0; page < cxt->oops_pages; page++) { | |
f0482ee3 RP |
232 | ret = mtd->read(mtd, page * OOPS_PAGE_SIZE, 8, &retlen, (u_char *) &count[0]); |
233 | if ((retlen != 8) || ((ret < 0) && (ret != -EUCLEAN))) { | |
234 | printk(KERN_ERR "mtdoops: Read failure at %d (%td of 8 read)" | |
2986bd2a RP |
235 | ", err %d.\n", page * OOPS_PAGE_SIZE, retlen, ret); |
236 | continue; | |
237 | } | |
238 | ||
f0482ee3 RP |
239 | if (count[1] != MTDOOPS_KERNMSG_MAGIC) |
240 | continue; | |
241 | if (count[0] == 0xffffffff) | |
4b23aff0 RP |
242 | continue; |
243 | if (maxcount == 0xffffffff) { | |
f0482ee3 | 244 | maxcount = count[0]; |
4b23aff0 | 245 | maxpos = page; |
f0482ee3 RP |
246 | } else if ((count[0] < 0x40000000) && (maxcount > 0xc0000000)) { |
247 | maxcount = count[0]; | |
4b23aff0 | 248 | maxpos = page; |
f0482ee3 RP |
249 | } else if ((count[0] > maxcount) && (count[0] < 0xc0000000)) { |
250 | maxcount = count[0]; | |
4b23aff0 | 251 | maxpos = page; |
f0482ee3 | 252 | } else if ((count[0] > maxcount) && (count[0] > 0xc0000000) |
4b23aff0 | 253 | && (maxcount > 0x80000000)) { |
f0482ee3 | 254 | maxcount = count[0]; |
4b23aff0 RP |
255 | maxpos = page; |
256 | } | |
257 | } | |
258 | if (maxcount == 0xffffffff) { | |
259 | cxt->nextpage = 0; | |
260 | cxt->nextcount = 1; | |
43b5693d | 261 | schedule_work(&cxt->work_erase); |
6ce0a856 | 262 | return; |
4b23aff0 RP |
263 | } |
264 | ||
265 | cxt->nextpage = maxpos; | |
266 | cxt->nextcount = maxcount; | |
267 | ||
6ce0a856 | 268 | mtdoops_inc_counter(cxt); |
4b23aff0 RP |
269 | } |
270 | ||
271 | ||
272 | static void mtdoops_notify_add(struct mtd_info *mtd) | |
273 | { | |
274 | struct mtdoops_context *cxt = &oops_cxt; | |
4b23aff0 RP |
275 | |
276 | if ((mtd->index != cxt->mtd_index) || cxt->mtd_index < 0) | |
277 | return; | |
278 | ||
279 | if (mtd->size < (mtd->erasesize * 2)) { | |
280 | printk(KERN_ERR "MTD partition %d not big enough for mtdoops\n", | |
281 | mtd->index); | |
282 | return; | |
283 | } | |
284 | ||
79dcd8e9 RP |
285 | if (mtd->erasesize < OOPS_PAGE_SIZE) { |
286 | printk(KERN_ERR "Eraseblock size of MTD partition %d too small\n", | |
287 | mtd->index); | |
288 | return; | |
289 | } | |
290 | ||
4b23aff0 RP |
291 | cxt->mtd = mtd; |
292 | cxt->oops_pages = mtd->size / OOPS_PAGE_SIZE; | |
293 | ||
6ce0a856 | 294 | find_next_position(cxt); |
4b23aff0 | 295 | |
79dcd8e9 | 296 | printk(KERN_INFO "mtdoops: Attached to MTD device %d\n", mtd->index); |
4b23aff0 RP |
297 | } |
298 | ||
299 | static void mtdoops_notify_remove(struct mtd_info *mtd) | |
300 | { | |
301 | struct mtdoops_context *cxt = &oops_cxt; | |
302 | ||
303 | if ((mtd->index != cxt->mtd_index) || cxt->mtd_index < 0) | |
304 | return; | |
305 | ||
306 | cxt->mtd = NULL; | |
307 | flush_scheduled_work(); | |
308 | } | |
309 | ||
8691a729 | 310 | static void mtdoops_console_sync(void) |
4b23aff0 | 311 | { |
8691a729 | 312 | struct mtdoops_context *cxt = &oops_cxt; |
4b23aff0 | 313 | struct mtd_info *mtd = cxt->mtd; |
47c152b8 | 314 | unsigned long flags; |
4b23aff0 | 315 | |
6ce0a856 | 316 | if (!cxt->ready || !mtd || cxt->writecount == 0) |
4b23aff0 RP |
317 | return; |
318 | ||
47c152b8 RP |
319 | /* |
320 | * Once ready is 0 and we've held the lock no further writes to the | |
321 | * buffer will happen | |
322 | */ | |
323 | spin_lock_irqsave(&cxt->writecount_lock, flags); | |
324 | if (!cxt->ready) { | |
325 | spin_unlock_irqrestore(&cxt->writecount_lock, flags); | |
326 | return; | |
327 | } | |
8691a729 | 328 | cxt->ready = 0; |
47c152b8 | 329 | spin_unlock_irqrestore(&cxt->writecount_lock, flags); |
8691a729 | 330 | |
621e4f8e RP |
331 | if (mtd->panic_write && in_interrupt()) |
332 | /* Interrupt context, we're going to panic so try and log */ | |
333 | mtdoops_write(cxt, 1); | |
334 | else | |
335 | schedule_work(&cxt->work_write); | |
8691a729 RP |
336 | } |
337 | ||
338 | static void | |
339 | mtdoops_console_write(struct console *co, const char *s, unsigned int count) | |
340 | { | |
341 | struct mtdoops_context *cxt = co->data; | |
342 | struct mtd_info *mtd = cxt->mtd; | |
47c152b8 | 343 | unsigned long flags; |
8691a729 RP |
344 | |
345 | if (!oops_in_progress) { | |
346 | mtdoops_console_sync(); | |
347 | return; | |
4b23aff0 RP |
348 | } |
349 | ||
8691a729 | 350 | if (!cxt->ready || !mtd) |
4b23aff0 RP |
351 | return; |
352 | ||
47c152b8 RP |
353 | /* Locking on writecount ensures sequential writes to the buffer */ |
354 | spin_lock_irqsave(&cxt->writecount_lock, flags); | |
355 | ||
356 | /* Check ready status didn't change whilst waiting for the lock */ | |
357 | if (!cxt->ready) | |
358 | return; | |
359 | ||
4b23aff0 RP |
360 | if (cxt->writecount == 0) { |
361 | u32 *stamp = cxt->oops_buf; | |
f0482ee3 RP |
362 | *stamp++ = cxt->nextcount; |
363 | *stamp = MTDOOPS_KERNMSG_MAGIC; | |
364 | cxt->writecount = 8; | |
4b23aff0 RP |
365 | } |
366 | ||
367 | if ((count + cxt->writecount) > OOPS_PAGE_SIZE) | |
368 | count = OOPS_PAGE_SIZE - cxt->writecount; | |
369 | ||
235d6200 PK |
370 | memcpy(cxt->oops_buf + cxt->writecount, s, count); |
371 | cxt->writecount += count; | |
47c152b8 RP |
372 | |
373 | spin_unlock_irqrestore(&cxt->writecount_lock, flags); | |
374 | ||
375 | if (cxt->writecount == OOPS_PAGE_SIZE) | |
376 | mtdoops_console_sync(); | |
4b23aff0 RP |
377 | } |
378 | ||
379 | static int __init mtdoops_console_setup(struct console *co, char *options) | |
380 | { | |
381 | struct mtdoops_context *cxt = co->data; | |
382 | ||
383 | if (cxt->mtd_index != -1) | |
384 | return -EBUSY; | |
385 | if (co->index == -1) | |
386 | return -EINVAL; | |
387 | ||
388 | cxt->mtd_index = co->index; | |
389 | return 0; | |
390 | } | |
391 | ||
392 | static struct mtd_notifier mtdoops_notifier = { | |
393 | .add = mtdoops_notify_add, | |
394 | .remove = mtdoops_notify_remove, | |
395 | }; | |
396 | ||
397 | static struct console mtdoops_console = { | |
398 | .name = "ttyMTD", | |
399 | .write = mtdoops_console_write, | |
400 | .setup = mtdoops_console_setup, | |
8691a729 | 401 | .unblank = mtdoops_console_sync, |
4b23aff0 RP |
402 | .index = -1, |
403 | .data = &oops_cxt, | |
404 | }; | |
405 | ||
406 | static int __init mtdoops_console_init(void) | |
407 | { | |
408 | struct mtdoops_context *cxt = &oops_cxt; | |
409 | ||
410 | cxt->mtd_index = -1; | |
411 | cxt->oops_buf = vmalloc(OOPS_PAGE_SIZE); | |
412 | ||
413 | if (!cxt->oops_buf) { | |
79dcd8e9 | 414 | printk(KERN_ERR "Failed to allocate mtdoops buffer workspace\n"); |
4b23aff0 RP |
415 | return -ENOMEM; |
416 | } | |
417 | ||
6ce0a856 RP |
418 | INIT_WORK(&cxt->work_erase, mtdoops_workfunc_erase); |
419 | INIT_WORK(&cxt->work_write, mtdoops_workfunc_write); | |
4b23aff0 RP |
420 | |
421 | register_console(&mtdoops_console); | |
422 | register_mtd_user(&mtdoops_notifier); | |
423 | return 0; | |
424 | } | |
425 | ||
426 | static void __exit mtdoops_console_exit(void) | |
427 | { | |
428 | struct mtdoops_context *cxt = &oops_cxt; | |
429 | ||
430 | unregister_mtd_user(&mtdoops_notifier); | |
431 | unregister_console(&mtdoops_console); | |
432 | vfree(cxt->oops_buf); | |
433 | } | |
434 | ||
435 | ||
436 | subsys_initcall(mtdoops_console_init); | |
437 | module_exit(mtdoops_console_exit); | |
438 | ||
439 | MODULE_LICENSE("GPL"); | |
440 | MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>"); | |
441 | MODULE_DESCRIPTION("MTD Oops/Panic console logger/driver"); |