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801c135c AB |
1 | /* |
2 | * Copyright (c) International Business Machines Corp., 2006 | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License as published by | |
6 | * the Free Software Foundation; either version 2 of the License, or | |
7 | * (at your option) any later version. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, | |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See | |
12 | * the GNU General Public License for more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License | |
15 | * along with this program; if not, write to the Free Software | |
16 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
17 | * | |
18 | * Authors: Artem Bityutskiy (Битюцкий Артём), Thomas Gleixner | |
19 | */ | |
20 | ||
21 | /* | |
22 | * UBI wear-leveling unit. | |
23 | * | |
24 | * This unit is responsible for wear-leveling. It works in terms of physical | |
25 | * eraseblocks and erase counters and knows nothing about logical eraseblocks, | |
26 | * volumes, etc. From this unit's perspective all physical eraseblocks are of | |
27 | * two types - used and free. Used physical eraseblocks are those that were | |
28 | * "get" by the 'ubi_wl_get_peb()' function, and free physical eraseblocks are | |
29 | * those that were put by the 'ubi_wl_put_peb()' function. | |
30 | * | |
31 | * Physical eraseblocks returned by 'ubi_wl_get_peb()' have only erase counter | |
32 | * header. The rest of the physical eraseblock contains only 0xFF bytes. | |
33 | * | |
34 | * When physical eraseblocks are returned to the WL unit by means of the | |
35 | * 'ubi_wl_put_peb()' function, they are scheduled for erasure. The erasure is | |
36 | * done asynchronously in context of the per-UBI device background thread, | |
37 | * which is also managed by the WL unit. | |
38 | * | |
39 | * The wear-leveling is ensured by means of moving the contents of used | |
40 | * physical eraseblocks with low erase counter to free physical eraseblocks | |
41 | * with high erase counter. | |
42 | * | |
43 | * The 'ubi_wl_get_peb()' function accepts data type hints which help to pick | |
44 | * an "optimal" physical eraseblock. For example, when it is known that the | |
45 | * physical eraseblock will be "put" soon because it contains short-term data, | |
46 | * the WL unit may pick a free physical eraseblock with low erase counter, and | |
47 | * so forth. | |
48 | * | |
49 | * If the WL unit fails to erase a physical eraseblock, it marks it as bad. | |
50 | * | |
51 | * This unit is also responsible for scrubbing. If a bit-flip is detected in a | |
52 | * physical eraseblock, it has to be moved. Technically this is the same as | |
53 | * moving it for wear-leveling reasons. | |
54 | * | |
55 | * As it was said, for the UBI unit all physical eraseblocks are either "free" | |
56 | * or "used". Free eraseblock are kept in the @wl->free RB-tree, while used | |
57 | * eraseblocks are kept in a set of different RB-trees: @wl->used, | |
58 | * @wl->prot.pnum, @wl->prot.aec, and @wl->scrub. | |
59 | * | |
60 | * Note, in this implementation, we keep a small in-RAM object for each physical | |
61 | * eraseblock. This is surely not a scalable solution. But it appears to be good | |
62 | * enough for moderately large flashes and it is simple. In future, one may | |
63 | * re-work this unit and make it more scalable. | |
64 | * | |
65 | * At the moment this unit does not utilize the sequence number, which was | |
66 | * introduced relatively recently. But it would be wise to do this because the | |
67 | * sequence number of a logical eraseblock characterizes how old is it. For | |
68 | * example, when we move a PEB with low erase counter, and we need to pick the | |
69 | * target PEB, we pick a PEB with the highest EC if our PEB is "old" and we | |
70 | * pick target PEB with an average EC if our PEB is not very "old". This is a | |
71 | * room for future re-works of the WL unit. | |
72 | * | |
73 | * FIXME: looks too complex, should be simplified (later). | |
74 | */ | |
75 | ||
76 | #include <linux/slab.h> | |
77 | #include <linux/crc32.h> | |
78 | #include <linux/freezer.h> | |
79 | #include <linux/kthread.h> | |
80 | #include "ubi.h" | |
81 | ||
82 | /* Number of physical eraseblocks reserved for wear-leveling purposes */ | |
83 | #define WL_RESERVED_PEBS 1 | |
84 | ||
85 | /* | |
86 | * How many erase cycles are short term, unknown, and long term physical | |
87 | * eraseblocks protected. | |
88 | */ | |
89 | #define ST_PROTECTION 16 | |
90 | #define U_PROTECTION 10 | |
91 | #define LT_PROTECTION 4 | |
92 | ||
93 | /* | |
94 | * Maximum difference between two erase counters. If this threshold is | |
95 | * exceeded, the WL unit starts moving data from used physical eraseblocks with | |
96 | * low erase counter to free physical eraseblocks with high erase counter. | |
97 | */ | |
98 | #define UBI_WL_THRESHOLD CONFIG_MTD_UBI_WL_THRESHOLD | |
99 | ||
100 | /* | |
101 | * When a physical eraseblock is moved, the WL unit has to pick the target | |
102 | * physical eraseblock to move to. The simplest way would be just to pick the | |
103 | * one with the highest erase counter. But in certain workloads this could lead | |
104 | * to an unlimited wear of one or few physical eraseblock. Indeed, imagine a | |
105 | * situation when the picked physical eraseblock is constantly erased after the | |
106 | * data is written to it. So, we have a constant which limits the highest erase | |
107 | * counter of the free physical eraseblock to pick. Namely, the WL unit does | |
108 | * not pick eraseblocks with erase counter greater then the lowest erase | |
109 | * counter plus %WL_FREE_MAX_DIFF. | |
110 | */ | |
111 | #define WL_FREE_MAX_DIFF (2*UBI_WL_THRESHOLD) | |
112 | ||
113 | /* | |
114 | * Maximum number of consecutive background thread failures which is enough to | |
115 | * switch to read-only mode. | |
116 | */ | |
117 | #define WL_MAX_FAILURES 32 | |
118 | ||
801c135c AB |
119 | /** |
120 | * struct ubi_wl_prot_entry - PEB protection entry. | |
121 | * @rb_pnum: link in the @wl->prot.pnum RB-tree | |
122 | * @rb_aec: link in the @wl->prot.aec RB-tree | |
123 | * @abs_ec: the absolute erase counter value when the protection ends | |
124 | * @e: the wear-leveling entry of the physical eraseblock under protection | |
125 | * | |
126 | * When the WL unit returns a physical eraseblock, the physical eraseblock is | |
127 | * protected from being moved for some "time". For this reason, the physical | |
128 | * eraseblock is not directly moved from the @wl->free tree to the @wl->used | |
129 | * tree. There is one more tree in between where this physical eraseblock is | |
130 | * temporarily stored (@wl->prot). | |
131 | * | |
132 | * All this protection stuff is needed because: | |
133 | * o we don't want to move physical eraseblocks just after we have given them | |
134 | * to the user; instead, we first want to let users fill them up with data; | |
135 | * | |
136 | * o there is a chance that the user will put the physical eraseblock very | |
137 | * soon, so it makes sense not to move it for some time, but wait; this is | |
138 | * especially important in case of "short term" physical eraseblocks. | |
139 | * | |
140 | * Physical eraseblocks stay protected only for limited time. But the "time" is | |
141 | * measured in erase cycles in this case. This is implemented with help of the | |
142 | * absolute erase counter (@wl->abs_ec). When it reaches certain value, the | |
143 | * physical eraseblocks are moved from the protection trees (@wl->prot.*) to | |
144 | * the @wl->used tree. | |
145 | * | |
146 | * Protected physical eraseblocks are searched by physical eraseblock number | |
147 | * (when they are put) and by the absolute erase counter (to check if it is | |
148 | * time to move them to the @wl->used tree). So there are actually 2 RB-trees | |
149 | * storing the protected physical eraseblocks: @wl->prot.pnum and | |
150 | * @wl->prot.aec. They are referred to as the "protection" trees. The | |
151 | * first one is indexed by the physical eraseblock number. The second one is | |
152 | * indexed by the absolute erase counter. Both trees store | |
153 | * &struct ubi_wl_prot_entry objects. | |
154 | * | |
155 | * Each physical eraseblock has 2 main states: free and used. The former state | |
156 | * corresponds to the @wl->free tree. The latter state is split up on several | |
157 | * sub-states: | |
158 | * o the WL movement is allowed (@wl->used tree); | |
159 | * o the WL movement is temporarily prohibited (@wl->prot.pnum and | |
160 | * @wl->prot.aec trees); | |
161 | * o scrubbing is needed (@wl->scrub tree). | |
162 | * | |
163 | * Depending on the sub-state, wear-leveling entries of the used physical | |
164 | * eraseblocks may be kept in one of those trees. | |
165 | */ | |
166 | struct ubi_wl_prot_entry { | |
167 | struct rb_node rb_pnum; | |
168 | struct rb_node rb_aec; | |
169 | unsigned long long abs_ec; | |
170 | struct ubi_wl_entry *e; | |
171 | }; | |
172 | ||
173 | /** | |
174 | * struct ubi_work - UBI work description data structure. | |
175 | * @list: a link in the list of pending works | |
176 | * @func: worker function | |
177 | * @priv: private data of the worker function | |
178 | * | |
179 | * @e: physical eraseblock to erase | |
180 | * @torture: if the physical eraseblock has to be tortured | |
181 | * | |
182 | * The @func pointer points to the worker function. If the @cancel argument is | |
183 | * not zero, the worker has to free the resources and exit immediately. The | |
184 | * worker has to return zero in case of success and a negative error code in | |
185 | * case of failure. | |
186 | */ | |
187 | struct ubi_work { | |
188 | struct list_head list; | |
189 | int (*func)(struct ubi_device *ubi, struct ubi_work *wrk, int cancel); | |
190 | /* The below fields are only relevant to erasure works */ | |
191 | struct ubi_wl_entry *e; | |
192 | int torture; | |
193 | }; | |
194 | ||
195 | #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID | |
e88d6e10 | 196 | static int paranoid_check_ec(struct ubi_device *ubi, int pnum, int ec); |
801c135c AB |
197 | static int paranoid_check_in_wl_tree(struct ubi_wl_entry *e, |
198 | struct rb_root *root); | |
199 | #else | |
200 | #define paranoid_check_ec(ubi, pnum, ec) 0 | |
201 | #define paranoid_check_in_wl_tree(e, root) | |
202 | #endif | |
203 | ||
801c135c AB |
204 | /** |
205 | * wl_tree_add - add a wear-leveling entry to a WL RB-tree. | |
206 | * @e: the wear-leveling entry to add | |
207 | * @root: the root of the tree | |
208 | * | |
209 | * Note, we use (erase counter, physical eraseblock number) pairs as keys in | |
210 | * the @ubi->used and @ubi->free RB-trees. | |
211 | */ | |
212 | static void wl_tree_add(struct ubi_wl_entry *e, struct rb_root *root) | |
213 | { | |
214 | struct rb_node **p, *parent = NULL; | |
215 | ||
216 | p = &root->rb_node; | |
217 | while (*p) { | |
218 | struct ubi_wl_entry *e1; | |
219 | ||
220 | parent = *p; | |
221 | e1 = rb_entry(parent, struct ubi_wl_entry, rb); | |
222 | ||
223 | if (e->ec < e1->ec) | |
224 | p = &(*p)->rb_left; | |
225 | else if (e->ec > e1->ec) | |
226 | p = &(*p)->rb_right; | |
227 | else { | |
228 | ubi_assert(e->pnum != e1->pnum); | |
229 | if (e->pnum < e1->pnum) | |
230 | p = &(*p)->rb_left; | |
231 | else | |
232 | p = &(*p)->rb_right; | |
233 | } | |
234 | } | |
235 | ||
236 | rb_link_node(&e->rb, parent, p); | |
237 | rb_insert_color(&e->rb, root); | |
238 | } | |
239 | ||
801c135c AB |
240 | /** |
241 | * do_work - do one pending work. | |
242 | * @ubi: UBI device description object | |
243 | * | |
244 | * This function returns zero in case of success and a negative error code in | |
245 | * case of failure. | |
246 | */ | |
247 | static int do_work(struct ubi_device *ubi) | |
248 | { | |
249 | int err; | |
250 | struct ubi_work *wrk; | |
251 | ||
43f9b25a AB |
252 | cond_resched(); |
253 | ||
801c135c AB |
254 | spin_lock(&ubi->wl_lock); |
255 | ||
256 | if (list_empty(&ubi->works)) { | |
257 | spin_unlock(&ubi->wl_lock); | |
258 | return 0; | |
259 | } | |
260 | ||
261 | wrk = list_entry(ubi->works.next, struct ubi_work, list); | |
262 | list_del(&wrk->list); | |
263 | spin_unlock(&ubi->wl_lock); | |
264 | ||
265 | /* | |
266 | * Call the worker function. Do not touch the work structure | |
267 | * after this call as it will have been freed or reused by that | |
268 | * time by the worker function. | |
269 | */ | |
270 | err = wrk->func(ubi, wrk, 0); | |
271 | if (err) | |
272 | ubi_err("work failed with error code %d", err); | |
273 | ||
274 | spin_lock(&ubi->wl_lock); | |
275 | ubi->works_count -= 1; | |
276 | ubi_assert(ubi->works_count >= 0); | |
277 | spin_unlock(&ubi->wl_lock); | |
278 | return err; | |
279 | } | |
280 | ||
281 | /** | |
282 | * produce_free_peb - produce a free physical eraseblock. | |
283 | * @ubi: UBI device description object | |
284 | * | |
285 | * This function tries to make a free PEB by means of synchronous execution of | |
286 | * pending works. This may be needed if, for example the background thread is | |
287 | * disabled. Returns zero in case of success and a negative error code in case | |
288 | * of failure. | |
289 | */ | |
290 | static int produce_free_peb(struct ubi_device *ubi) | |
291 | { | |
292 | int err; | |
293 | ||
294 | spin_lock(&ubi->wl_lock); | |
5abde384 | 295 | while (!ubi->free.rb_node) { |
801c135c AB |
296 | spin_unlock(&ubi->wl_lock); |
297 | ||
298 | dbg_wl("do one work synchronously"); | |
299 | err = do_work(ubi); | |
300 | if (err) | |
301 | return err; | |
302 | ||
303 | spin_lock(&ubi->wl_lock); | |
304 | } | |
305 | spin_unlock(&ubi->wl_lock); | |
306 | ||
307 | return 0; | |
308 | } | |
309 | ||
310 | /** | |
311 | * in_wl_tree - check if wear-leveling entry is present in a WL RB-tree. | |
312 | * @e: the wear-leveling entry to check | |
313 | * @root: the root of the tree | |
314 | * | |
315 | * This function returns non-zero if @e is in the @root RB-tree and zero if it | |
316 | * is not. | |
317 | */ | |
318 | static int in_wl_tree(struct ubi_wl_entry *e, struct rb_root *root) | |
319 | { | |
320 | struct rb_node *p; | |
321 | ||
322 | p = root->rb_node; | |
323 | while (p) { | |
324 | struct ubi_wl_entry *e1; | |
325 | ||
326 | e1 = rb_entry(p, struct ubi_wl_entry, rb); | |
327 | ||
328 | if (e->pnum == e1->pnum) { | |
329 | ubi_assert(e == e1); | |
330 | return 1; | |
331 | } | |
332 | ||
333 | if (e->ec < e1->ec) | |
334 | p = p->rb_left; | |
335 | else if (e->ec > e1->ec) | |
336 | p = p->rb_right; | |
337 | else { | |
338 | ubi_assert(e->pnum != e1->pnum); | |
339 | if (e->pnum < e1->pnum) | |
340 | p = p->rb_left; | |
341 | else | |
342 | p = p->rb_right; | |
343 | } | |
344 | } | |
345 | ||
346 | return 0; | |
347 | } | |
348 | ||
349 | /** | |
350 | * prot_tree_add - add physical eraseblock to protection trees. | |
351 | * @ubi: UBI device description object | |
352 | * @e: the physical eraseblock to add | |
353 | * @pe: protection entry object to use | |
354 | * @abs_ec: absolute erase counter value when this physical eraseblock has | |
355 | * to be removed from the protection trees. | |
356 | * | |
357 | * @wl->lock has to be locked. | |
358 | */ | |
359 | static void prot_tree_add(struct ubi_device *ubi, struct ubi_wl_entry *e, | |
360 | struct ubi_wl_prot_entry *pe, int abs_ec) | |
361 | { | |
362 | struct rb_node **p, *parent = NULL; | |
363 | struct ubi_wl_prot_entry *pe1; | |
364 | ||
365 | pe->e = e; | |
366 | pe->abs_ec = ubi->abs_ec + abs_ec; | |
367 | ||
368 | p = &ubi->prot.pnum.rb_node; | |
369 | while (*p) { | |
370 | parent = *p; | |
371 | pe1 = rb_entry(parent, struct ubi_wl_prot_entry, rb_pnum); | |
372 | ||
373 | if (e->pnum < pe1->e->pnum) | |
374 | p = &(*p)->rb_left; | |
375 | else | |
376 | p = &(*p)->rb_right; | |
377 | } | |
378 | rb_link_node(&pe->rb_pnum, parent, p); | |
379 | rb_insert_color(&pe->rb_pnum, &ubi->prot.pnum); | |
380 | ||
381 | p = &ubi->prot.aec.rb_node; | |
382 | parent = NULL; | |
383 | while (*p) { | |
384 | parent = *p; | |
385 | pe1 = rb_entry(parent, struct ubi_wl_prot_entry, rb_aec); | |
386 | ||
387 | if (pe->abs_ec < pe1->abs_ec) | |
388 | p = &(*p)->rb_left; | |
389 | else | |
390 | p = &(*p)->rb_right; | |
391 | } | |
392 | rb_link_node(&pe->rb_aec, parent, p); | |
393 | rb_insert_color(&pe->rb_aec, &ubi->prot.aec); | |
394 | } | |
395 | ||
396 | /** | |
397 | * find_wl_entry - find wear-leveling entry closest to certain erase counter. | |
398 | * @root: the RB-tree where to look for | |
399 | * @max: highest possible erase counter | |
400 | * | |
401 | * This function looks for a wear leveling entry with erase counter closest to | |
402 | * @max and less then @max. | |
403 | */ | |
404 | static struct ubi_wl_entry *find_wl_entry(struct rb_root *root, int max) | |
405 | { | |
406 | struct rb_node *p; | |
407 | struct ubi_wl_entry *e; | |
408 | ||
409 | e = rb_entry(rb_first(root), struct ubi_wl_entry, rb); | |
410 | max += e->ec; | |
411 | ||
412 | p = root->rb_node; | |
413 | while (p) { | |
414 | struct ubi_wl_entry *e1; | |
415 | ||
416 | e1 = rb_entry(p, struct ubi_wl_entry, rb); | |
417 | if (e1->ec >= max) | |
418 | p = p->rb_left; | |
419 | else { | |
420 | p = p->rb_right; | |
421 | e = e1; | |
422 | } | |
423 | } | |
424 | ||
425 | return e; | |
426 | } | |
427 | ||
428 | /** | |
429 | * ubi_wl_get_peb - get a physical eraseblock. | |
430 | * @ubi: UBI device description object | |
431 | * @dtype: type of data which will be stored in this physical eraseblock | |
432 | * | |
433 | * This function returns a physical eraseblock in case of success and a | |
434 | * negative error code in case of failure. Might sleep. | |
435 | */ | |
436 | int ubi_wl_get_peb(struct ubi_device *ubi, int dtype) | |
437 | { | |
438 | int err, protect, medium_ec; | |
439 | struct ubi_wl_entry *e, *first, *last; | |
440 | struct ubi_wl_prot_entry *pe; | |
441 | ||
442 | ubi_assert(dtype == UBI_LONGTERM || dtype == UBI_SHORTTERM || | |
443 | dtype == UBI_UNKNOWN); | |
444 | ||
33818bbb | 445 | pe = kmalloc(sizeof(struct ubi_wl_prot_entry), GFP_NOFS); |
801c135c AB |
446 | if (!pe) |
447 | return -ENOMEM; | |
448 | ||
449 | retry: | |
450 | spin_lock(&ubi->wl_lock); | |
5abde384 | 451 | if (!ubi->free.rb_node) { |
801c135c AB |
452 | if (ubi->works_count == 0) { |
453 | ubi_assert(list_empty(&ubi->works)); | |
454 | ubi_err("no free eraseblocks"); | |
455 | spin_unlock(&ubi->wl_lock); | |
456 | kfree(pe); | |
457 | return -ENOSPC; | |
458 | } | |
459 | spin_unlock(&ubi->wl_lock); | |
460 | ||
461 | err = produce_free_peb(ubi); | |
462 | if (err < 0) { | |
463 | kfree(pe); | |
464 | return err; | |
465 | } | |
466 | goto retry; | |
467 | } | |
468 | ||
469 | switch (dtype) { | |
470 | case UBI_LONGTERM: | |
471 | /* | |
472 | * For long term data we pick a physical eraseblock | |
473 | * with high erase counter. But the highest erase | |
474 | * counter we can pick is bounded by the the lowest | |
475 | * erase counter plus %WL_FREE_MAX_DIFF. | |
476 | */ | |
477 | e = find_wl_entry(&ubi->free, WL_FREE_MAX_DIFF); | |
478 | protect = LT_PROTECTION; | |
479 | break; | |
480 | case UBI_UNKNOWN: | |
481 | /* | |
482 | * For unknown data we pick a physical eraseblock with | |
483 | * medium erase counter. But we by no means can pick a | |
484 | * physical eraseblock with erase counter greater or | |
485 | * equivalent than the lowest erase counter plus | |
486 | * %WL_FREE_MAX_DIFF. | |
487 | */ | |
488 | first = rb_entry(rb_first(&ubi->free), | |
489 | struct ubi_wl_entry, rb); | |
490 | last = rb_entry(rb_last(&ubi->free), | |
491 | struct ubi_wl_entry, rb); | |
492 | ||
493 | if (last->ec - first->ec < WL_FREE_MAX_DIFF) | |
494 | e = rb_entry(ubi->free.rb_node, | |
495 | struct ubi_wl_entry, rb); | |
496 | else { | |
497 | medium_ec = (first->ec + WL_FREE_MAX_DIFF)/2; | |
498 | e = find_wl_entry(&ubi->free, medium_ec); | |
499 | } | |
500 | protect = U_PROTECTION; | |
501 | break; | |
502 | case UBI_SHORTTERM: | |
503 | /* | |
504 | * For short term data we pick a physical eraseblock | |
505 | * with the lowest erase counter as we expect it will | |
506 | * be erased soon. | |
507 | */ | |
508 | e = rb_entry(rb_first(&ubi->free), | |
509 | struct ubi_wl_entry, rb); | |
510 | protect = ST_PROTECTION; | |
511 | break; | |
512 | default: | |
513 | protect = 0; | |
514 | e = NULL; | |
515 | BUG(); | |
516 | } | |
517 | ||
518 | /* | |
519 | * Move the physical eraseblock to the protection trees where it will | |
520 | * be protected from being moved for some time. | |
521 | */ | |
5abde384 AB |
522 | paranoid_check_in_wl_tree(e, &ubi->free); |
523 | rb_erase(&e->rb, &ubi->free); | |
801c135c AB |
524 | prot_tree_add(ubi, e, pe, protect); |
525 | ||
526 | dbg_wl("PEB %d EC %d, protection %d", e->pnum, e->ec, protect); | |
527 | spin_unlock(&ubi->wl_lock); | |
528 | ||
529 | return e->pnum; | |
530 | } | |
531 | ||
532 | /** | |
533 | * prot_tree_del - remove a physical eraseblock from the protection trees | |
534 | * @ubi: UBI device description object | |
535 | * @pnum: the physical eraseblock to remove | |
43f9b25a AB |
536 | * |
537 | * This function returns PEB @pnum from the protection trees and returns zero | |
538 | * in case of success and %-ENODEV if the PEB was not found in the protection | |
539 | * trees. | |
801c135c | 540 | */ |
43f9b25a | 541 | static int prot_tree_del(struct ubi_device *ubi, int pnum) |
801c135c AB |
542 | { |
543 | struct rb_node *p; | |
544 | struct ubi_wl_prot_entry *pe = NULL; | |
545 | ||
546 | p = ubi->prot.pnum.rb_node; | |
547 | while (p) { | |
548 | ||
549 | pe = rb_entry(p, struct ubi_wl_prot_entry, rb_pnum); | |
550 | ||
551 | if (pnum == pe->e->pnum) | |
43f9b25a | 552 | goto found; |
801c135c AB |
553 | |
554 | if (pnum < pe->e->pnum) | |
555 | p = p->rb_left; | |
556 | else | |
557 | p = p->rb_right; | |
558 | } | |
559 | ||
43f9b25a AB |
560 | return -ENODEV; |
561 | ||
562 | found: | |
801c135c AB |
563 | ubi_assert(pe->e->pnum == pnum); |
564 | rb_erase(&pe->rb_aec, &ubi->prot.aec); | |
565 | rb_erase(&pe->rb_pnum, &ubi->prot.pnum); | |
566 | kfree(pe); | |
43f9b25a | 567 | return 0; |
801c135c AB |
568 | } |
569 | ||
570 | /** | |
571 | * sync_erase - synchronously erase a physical eraseblock. | |
572 | * @ubi: UBI device description object | |
573 | * @e: the the physical eraseblock to erase | |
574 | * @torture: if the physical eraseblock has to be tortured | |
575 | * | |
576 | * This function returns zero in case of success and a negative error code in | |
577 | * case of failure. | |
578 | */ | |
579 | static int sync_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, int torture) | |
580 | { | |
581 | int err; | |
582 | struct ubi_ec_hdr *ec_hdr; | |
583 | unsigned long long ec = e->ec; | |
584 | ||
585 | dbg_wl("erase PEB %d, old EC %llu", e->pnum, ec); | |
586 | ||
587 | err = paranoid_check_ec(ubi, e->pnum, e->ec); | |
588 | if (err > 0) | |
589 | return -EINVAL; | |
590 | ||
33818bbb | 591 | ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_NOFS); |
801c135c AB |
592 | if (!ec_hdr) |
593 | return -ENOMEM; | |
594 | ||
595 | err = ubi_io_sync_erase(ubi, e->pnum, torture); | |
596 | if (err < 0) | |
597 | goto out_free; | |
598 | ||
599 | ec += err; | |
600 | if (ec > UBI_MAX_ERASECOUNTER) { | |
601 | /* | |
602 | * Erase counter overflow. Upgrade UBI and use 64-bit | |
603 | * erase counters internally. | |
604 | */ | |
605 | ubi_err("erase counter overflow at PEB %d, EC %llu", | |
606 | e->pnum, ec); | |
607 | err = -EINVAL; | |
608 | goto out_free; | |
609 | } | |
610 | ||
611 | dbg_wl("erased PEB %d, new EC %llu", e->pnum, ec); | |
612 | ||
3261ebd7 | 613 | ec_hdr->ec = cpu_to_be64(ec); |
801c135c AB |
614 | |
615 | err = ubi_io_write_ec_hdr(ubi, e->pnum, ec_hdr); | |
616 | if (err) | |
617 | goto out_free; | |
618 | ||
619 | e->ec = ec; | |
620 | spin_lock(&ubi->wl_lock); | |
621 | if (e->ec > ubi->max_ec) | |
622 | ubi->max_ec = e->ec; | |
623 | spin_unlock(&ubi->wl_lock); | |
624 | ||
625 | out_free: | |
626 | kfree(ec_hdr); | |
627 | return err; | |
628 | } | |
629 | ||
630 | /** | |
631 | * check_protection_over - check if it is time to stop protecting some | |
632 | * physical eraseblocks. | |
633 | * @ubi: UBI device description object | |
634 | * | |
635 | * This function is called after each erase operation, when the absolute erase | |
636 | * counter is incremented, to check if some physical eraseblock have not to be | |
637 | * protected any longer. These physical eraseblocks are moved from the | |
638 | * protection trees to the used tree. | |
639 | */ | |
640 | static void check_protection_over(struct ubi_device *ubi) | |
641 | { | |
642 | struct ubi_wl_prot_entry *pe; | |
643 | ||
644 | /* | |
645 | * There may be several protected physical eraseblock to remove, | |
646 | * process them all. | |
647 | */ | |
648 | while (1) { | |
649 | spin_lock(&ubi->wl_lock); | |
5abde384 | 650 | if (!ubi->prot.aec.rb_node) { |
801c135c AB |
651 | spin_unlock(&ubi->wl_lock); |
652 | break; | |
653 | } | |
654 | ||
655 | pe = rb_entry(rb_first(&ubi->prot.aec), | |
656 | struct ubi_wl_prot_entry, rb_aec); | |
657 | ||
658 | if (pe->abs_ec > ubi->abs_ec) { | |
659 | spin_unlock(&ubi->wl_lock); | |
660 | break; | |
661 | } | |
662 | ||
663 | dbg_wl("PEB %d protection over, abs_ec %llu, PEB abs_ec %llu", | |
664 | pe->e->pnum, ubi->abs_ec, pe->abs_ec); | |
665 | rb_erase(&pe->rb_aec, &ubi->prot.aec); | |
666 | rb_erase(&pe->rb_pnum, &ubi->prot.pnum); | |
5abde384 | 667 | wl_tree_add(pe->e, &ubi->used); |
801c135c AB |
668 | spin_unlock(&ubi->wl_lock); |
669 | ||
670 | kfree(pe); | |
671 | cond_resched(); | |
672 | } | |
673 | } | |
674 | ||
675 | /** | |
676 | * schedule_ubi_work - schedule a work. | |
677 | * @ubi: UBI device description object | |
678 | * @wrk: the work to schedule | |
679 | * | |
680 | * This function enqueues a work defined by @wrk to the tail of the pending | |
681 | * works list. | |
682 | */ | |
683 | static void schedule_ubi_work(struct ubi_device *ubi, struct ubi_work *wrk) | |
684 | { | |
685 | spin_lock(&ubi->wl_lock); | |
686 | list_add_tail(&wrk->list, &ubi->works); | |
687 | ubi_assert(ubi->works_count >= 0); | |
688 | ubi->works_count += 1; | |
689 | if (ubi->thread_enabled) | |
690 | wake_up_process(ubi->bgt_thread); | |
691 | spin_unlock(&ubi->wl_lock); | |
692 | } | |
693 | ||
694 | static int erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk, | |
695 | int cancel); | |
696 | ||
697 | /** | |
698 | * schedule_erase - schedule an erase work. | |
699 | * @ubi: UBI device description object | |
700 | * @e: the WL entry of the physical eraseblock to erase | |
701 | * @torture: if the physical eraseblock has to be tortured | |
702 | * | |
703 | * This function returns zero in case of success and a %-ENOMEM in case of | |
704 | * failure. | |
705 | */ | |
706 | static int schedule_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, | |
707 | int torture) | |
708 | { | |
709 | struct ubi_work *wl_wrk; | |
710 | ||
711 | dbg_wl("schedule erasure of PEB %d, EC %d, torture %d", | |
712 | e->pnum, e->ec, torture); | |
713 | ||
33818bbb | 714 | wl_wrk = kmalloc(sizeof(struct ubi_work), GFP_NOFS); |
801c135c AB |
715 | if (!wl_wrk) |
716 | return -ENOMEM; | |
717 | ||
718 | wl_wrk->func = &erase_worker; | |
719 | wl_wrk->e = e; | |
720 | wl_wrk->torture = torture; | |
721 | ||
722 | schedule_ubi_work(ubi, wl_wrk); | |
723 | return 0; | |
724 | } | |
725 | ||
726 | /** | |
727 | * wear_leveling_worker - wear-leveling worker function. | |
728 | * @ubi: UBI device description object | |
729 | * @wrk: the work object | |
730 | * @cancel: non-zero if the worker has to free memory and exit | |
731 | * | |
732 | * This function copies a more worn out physical eraseblock to a less worn out | |
733 | * one. Returns zero in case of success and a negative error code in case of | |
734 | * failure. | |
735 | */ | |
736 | static int wear_leveling_worker(struct ubi_device *ubi, struct ubi_work *wrk, | |
737 | int cancel) | |
738 | { | |
43f9b25a AB |
739 | int err, put = 0, scrubbing = 0, protect = 0; |
740 | struct ubi_wl_prot_entry *pe; | |
801c135c AB |
741 | struct ubi_wl_entry *e1, *e2; |
742 | struct ubi_vid_hdr *vid_hdr; | |
743 | ||
744 | kfree(wrk); | |
745 | ||
746 | if (cancel) | |
747 | return 0; | |
748 | ||
33818bbb | 749 | vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS); |
801c135c AB |
750 | if (!vid_hdr) |
751 | return -ENOMEM; | |
752 | ||
43f9b25a | 753 | mutex_lock(&ubi->move_mutex); |
801c135c | 754 | spin_lock(&ubi->wl_lock); |
43f9b25a AB |
755 | ubi_assert(!ubi->move_from && !ubi->move_to); |
756 | ubi_assert(!ubi->move_to_put); | |
801c135c | 757 | |
43f9b25a | 758 | if (!ubi->free.rb_node || |
5abde384 | 759 | (!ubi->used.rb_node && !ubi->scrub.rb_node)) { |
801c135c | 760 | /* |
43f9b25a AB |
761 | * No free physical eraseblocks? Well, they must be waiting in |
762 | * the queue to be erased. Cancel movement - it will be | |
763 | * triggered again when a free physical eraseblock appears. | |
801c135c AB |
764 | * |
765 | * No used physical eraseblocks? They must be temporarily | |
766 | * protected from being moved. They will be moved to the | |
767 | * @ubi->used tree later and the wear-leveling will be | |
768 | * triggered again. | |
769 | */ | |
770 | dbg_wl("cancel WL, a list is empty: free %d, used %d", | |
5abde384 | 771 | !ubi->free.rb_node, !ubi->used.rb_node); |
43f9b25a | 772 | goto out_cancel; |
801c135c AB |
773 | } |
774 | ||
5abde384 | 775 | if (!ubi->scrub.rb_node) { |
801c135c AB |
776 | /* |
777 | * Now pick the least worn-out used physical eraseblock and a | |
778 | * highly worn-out free physical eraseblock. If the erase | |
779 | * counters differ much enough, start wear-leveling. | |
780 | */ | |
781 | e1 = rb_entry(rb_first(&ubi->used), struct ubi_wl_entry, rb); | |
782 | e2 = find_wl_entry(&ubi->free, WL_FREE_MAX_DIFF); | |
783 | ||
784 | if (!(e2->ec - e1->ec >= UBI_WL_THRESHOLD)) { | |
785 | dbg_wl("no WL needed: min used EC %d, max free EC %d", | |
786 | e1->ec, e2->ec); | |
43f9b25a | 787 | goto out_cancel; |
801c135c | 788 | } |
5abde384 AB |
789 | paranoid_check_in_wl_tree(e1, &ubi->used); |
790 | rb_erase(&e1->rb, &ubi->used); | |
801c135c AB |
791 | dbg_wl("move PEB %d EC %d to PEB %d EC %d", |
792 | e1->pnum, e1->ec, e2->pnum, e2->ec); | |
793 | } else { | |
43f9b25a AB |
794 | /* Perform scrubbing */ |
795 | scrubbing = 1; | |
801c135c AB |
796 | e1 = rb_entry(rb_first(&ubi->scrub), struct ubi_wl_entry, rb); |
797 | e2 = find_wl_entry(&ubi->free, WL_FREE_MAX_DIFF); | |
5abde384 | 798 | paranoid_check_in_wl_tree(e1, &ubi->scrub); |
d2c46855 | 799 | rb_erase(&e1->rb, &ubi->scrub); |
801c135c AB |
800 | dbg_wl("scrub PEB %d to PEB %d", e1->pnum, e2->pnum); |
801 | } | |
802 | ||
5abde384 AB |
803 | paranoid_check_in_wl_tree(e2, &ubi->free); |
804 | rb_erase(&e2->rb, &ubi->free); | |
801c135c AB |
805 | ubi->move_from = e1; |
806 | ubi->move_to = e2; | |
807 | spin_unlock(&ubi->wl_lock); | |
808 | ||
809 | /* | |
810 | * Now we are going to copy physical eraseblock @e1->pnum to @e2->pnum. | |
811 | * We so far do not know which logical eraseblock our physical | |
812 | * eraseblock (@e1) belongs to. We have to read the volume identifier | |
813 | * header first. | |
43f9b25a AB |
814 | * |
815 | * Note, we are protected from this PEB being unmapped and erased. The | |
816 | * 'ubi_wl_put_peb()' would wait for moving to be finished if the PEB | |
817 | * which is being moved was unmapped. | |
801c135c AB |
818 | */ |
819 | ||
820 | err = ubi_io_read_vid_hdr(ubi, e1->pnum, vid_hdr, 0); | |
821 | if (err && err != UBI_IO_BITFLIPS) { | |
822 | if (err == UBI_IO_PEB_FREE) { | |
823 | /* | |
824 | * We are trying to move PEB without a VID header. UBI | |
825 | * always write VID headers shortly after the PEB was | |
826 | * given, so we have a situation when it did not have | |
827 | * chance to write it down because it was preempted. | |
828 | * Just re-schedule the work, so that next time it will | |
829 | * likely have the VID header in place. | |
830 | */ | |
831 | dbg_wl("PEB %d has no VID header", e1->pnum); | |
43f9b25a | 832 | goto out_not_moved; |
801c135c | 833 | } |
43f9b25a AB |
834 | |
835 | ubi_err("error %d while reading VID header from PEB %d", | |
836 | err, e1->pnum); | |
837 | if (err > 0) | |
838 | err = -EIO; | |
839 | goto out_error; | |
801c135c AB |
840 | } |
841 | ||
842 | err = ubi_eba_copy_leb(ubi, e1->pnum, e2->pnum, vid_hdr); | |
843 | if (err) { | |
43f9b25a AB |
844 | |
845 | if (err < 0) | |
846 | goto out_error; | |
847 | if (err == 1) | |
848 | goto out_not_moved; | |
849 | ||
850 | /* | |
851 | * For some reason the LEB was not moved - it might be because | |
852 | * the volume is being deleted. We should prevent this PEB from | |
853 | * being selected for wear-levelling movement for some "time", | |
854 | * so put it to the protection tree. | |
855 | */ | |
856 | ||
857 | dbg_wl("cancelled moving PEB %d", e1->pnum); | |
858 | pe = kmalloc(sizeof(struct ubi_wl_prot_entry), GFP_NOFS); | |
859 | if (!pe) { | |
860 | err = -ENOMEM; | |
861 | goto out_error; | |
862 | } | |
863 | ||
864 | protect = 1; | |
801c135c AB |
865 | } |
866 | ||
867 | ubi_free_vid_hdr(ubi, vid_hdr); | |
868 | spin_lock(&ubi->wl_lock); | |
43f9b25a AB |
869 | if (protect) |
870 | prot_tree_add(ubi, e1, pe, protect); | |
801c135c | 871 | if (!ubi->move_to_put) |
5abde384 | 872 | wl_tree_add(e2, &ubi->used); |
801c135c AB |
873 | else |
874 | put = 1; | |
875 | ubi->move_from = ubi->move_to = NULL; | |
43f9b25a | 876 | ubi->move_to_put = ubi->wl_scheduled = 0; |
801c135c AB |
877 | spin_unlock(&ubi->wl_lock); |
878 | ||
879 | if (put) { | |
880 | /* | |
881 | * Well, the target PEB was put meanwhile, schedule it for | |
882 | * erasure. | |
883 | */ | |
884 | dbg_wl("PEB %d was put meanwhile, erase", e2->pnum); | |
885 | err = schedule_erase(ubi, e2, 0); | |
43f9b25a AB |
886 | if (err) |
887 | goto out_error; | |
801c135c AB |
888 | } |
889 | ||
43f9b25a AB |
890 | if (!protect) { |
891 | err = schedule_erase(ubi, e1, 0); | |
892 | if (err) | |
893 | goto out_error; | |
801c135c AB |
894 | } |
895 | ||
43f9b25a | 896 | |
801c135c | 897 | dbg_wl("done"); |
43f9b25a AB |
898 | mutex_unlock(&ubi->move_mutex); |
899 | return 0; | |
801c135c AB |
900 | |
901 | /* | |
43f9b25a AB |
902 | * For some reasons the LEB was not moved, might be an error, might be |
903 | * something else. @e1 was not changed, so return it back. @e2 might | |
904 | * be changed, schedule it for erasure. | |
801c135c | 905 | */ |
43f9b25a | 906 | out_not_moved: |
801c135c AB |
907 | ubi_free_vid_hdr(ubi, vid_hdr); |
908 | spin_lock(&ubi->wl_lock); | |
43f9b25a AB |
909 | if (scrubbing) |
910 | wl_tree_add(e1, &ubi->scrub); | |
801c135c | 911 | else |
5abde384 | 912 | wl_tree_add(e1, &ubi->used); |
801c135c | 913 | ubi->move_from = ubi->move_to = NULL; |
43f9b25a | 914 | ubi->move_to_put = ubi->wl_scheduled = 0; |
801c135c AB |
915 | spin_unlock(&ubi->wl_lock); |
916 | ||
801c135c | 917 | err = schedule_erase(ubi, e2, 0); |
43f9b25a AB |
918 | if (err) |
919 | goto out_error; | |
920 | ||
921 | mutex_unlock(&ubi->move_mutex); | |
922 | return 0; | |
923 | ||
924 | out_error: | |
925 | ubi_err("error %d while moving PEB %d to PEB %d", | |
926 | err, e1->pnum, e2->pnum); | |
801c135c | 927 | |
43f9b25a AB |
928 | ubi_free_vid_hdr(ubi, vid_hdr); |
929 | spin_lock(&ubi->wl_lock); | |
930 | ubi->move_from = ubi->move_to = NULL; | |
931 | ubi->move_to_put = ubi->wl_scheduled = 0; | |
932 | spin_unlock(&ubi->wl_lock); | |
933 | ||
934 | kmem_cache_free(ubi_wl_entry_slab, e1); | |
935 | kmem_cache_free(ubi_wl_entry_slab, e2); | |
936 | ubi_ro_mode(ubi); | |
937 | ||
938 | mutex_unlock(&ubi->move_mutex); | |
801c135c | 939 | return err; |
43f9b25a AB |
940 | |
941 | out_cancel: | |
942 | ubi->wl_scheduled = 0; | |
943 | spin_unlock(&ubi->wl_lock); | |
944 | mutex_unlock(&ubi->move_mutex); | |
945 | ubi_free_vid_hdr(ubi, vid_hdr); | |
946 | return 0; | |
801c135c AB |
947 | } |
948 | ||
949 | /** | |
950 | * ensure_wear_leveling - schedule wear-leveling if it is needed. | |
951 | * @ubi: UBI device description object | |
952 | * | |
953 | * This function checks if it is time to start wear-leveling and schedules it | |
954 | * if yes. This function returns zero in case of success and a negative error | |
955 | * code in case of failure. | |
956 | */ | |
957 | static int ensure_wear_leveling(struct ubi_device *ubi) | |
958 | { | |
959 | int err = 0; | |
960 | struct ubi_wl_entry *e1; | |
961 | struct ubi_wl_entry *e2; | |
962 | struct ubi_work *wrk; | |
963 | ||
964 | spin_lock(&ubi->wl_lock); | |
965 | if (ubi->wl_scheduled) | |
966 | /* Wear-leveling is already in the work queue */ | |
967 | goto out_unlock; | |
968 | ||
969 | /* | |
970 | * If the ubi->scrub tree is not empty, scrubbing is needed, and the | |
971 | * the WL worker has to be scheduled anyway. | |
972 | */ | |
5abde384 AB |
973 | if (!ubi->scrub.rb_node) { |
974 | if (!ubi->used.rb_node || !ubi->free.rb_node) | |
801c135c AB |
975 | /* No physical eraseblocks - no deal */ |
976 | goto out_unlock; | |
977 | ||
978 | /* | |
979 | * We schedule wear-leveling only if the difference between the | |
980 | * lowest erase counter of used physical eraseblocks and a high | |
981 | * erase counter of free physical eraseblocks is greater then | |
982 | * %UBI_WL_THRESHOLD. | |
983 | */ | |
984 | e1 = rb_entry(rb_first(&ubi->used), struct ubi_wl_entry, rb); | |
985 | e2 = find_wl_entry(&ubi->free, WL_FREE_MAX_DIFF); | |
986 | ||
987 | if (!(e2->ec - e1->ec >= UBI_WL_THRESHOLD)) | |
988 | goto out_unlock; | |
989 | dbg_wl("schedule wear-leveling"); | |
990 | } else | |
991 | dbg_wl("schedule scrubbing"); | |
992 | ||
993 | ubi->wl_scheduled = 1; | |
994 | spin_unlock(&ubi->wl_lock); | |
995 | ||
33818bbb | 996 | wrk = kmalloc(sizeof(struct ubi_work), GFP_NOFS); |
801c135c AB |
997 | if (!wrk) { |
998 | err = -ENOMEM; | |
999 | goto out_cancel; | |
1000 | } | |
1001 | ||
1002 | wrk->func = &wear_leveling_worker; | |
1003 | schedule_ubi_work(ubi, wrk); | |
1004 | return err; | |
1005 | ||
1006 | out_cancel: | |
1007 | spin_lock(&ubi->wl_lock); | |
1008 | ubi->wl_scheduled = 0; | |
1009 | out_unlock: | |
1010 | spin_unlock(&ubi->wl_lock); | |
1011 | return err; | |
1012 | } | |
1013 | ||
1014 | /** | |
1015 | * erase_worker - physical eraseblock erase worker function. | |
1016 | * @ubi: UBI device description object | |
1017 | * @wl_wrk: the work object | |
1018 | * @cancel: non-zero if the worker has to free memory and exit | |
1019 | * | |
1020 | * This function erases a physical eraseblock and perform torture testing if | |
1021 | * needed. It also takes care about marking the physical eraseblock bad if | |
1022 | * needed. Returns zero in case of success and a negative error code in case of | |
1023 | * failure. | |
1024 | */ | |
1025 | static int erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk, | |
1026 | int cancel) | |
1027 | { | |
801c135c | 1028 | struct ubi_wl_entry *e = wl_wrk->e; |
784c1454 | 1029 | int pnum = e->pnum, err, need; |
801c135c AB |
1030 | |
1031 | if (cancel) { | |
1032 | dbg_wl("cancel erasure of PEB %d EC %d", pnum, e->ec); | |
1033 | kfree(wl_wrk); | |
06b68ba1 | 1034 | kmem_cache_free(ubi_wl_entry_slab, e); |
801c135c AB |
1035 | return 0; |
1036 | } | |
1037 | ||
1038 | dbg_wl("erase PEB %d EC %d", pnum, e->ec); | |
1039 | ||
1040 | err = sync_erase(ubi, e, wl_wrk->torture); | |
1041 | if (!err) { | |
1042 | /* Fine, we've erased it successfully */ | |
1043 | kfree(wl_wrk); | |
1044 | ||
1045 | spin_lock(&ubi->wl_lock); | |
1046 | ubi->abs_ec += 1; | |
5abde384 | 1047 | wl_tree_add(e, &ubi->free); |
801c135c AB |
1048 | spin_unlock(&ubi->wl_lock); |
1049 | ||
1050 | /* | |
1051 | * One more erase operation has happened, take care about protected | |
1052 | * physical eraseblocks. | |
1053 | */ | |
1054 | check_protection_over(ubi); | |
1055 | ||
1056 | /* And take care about wear-leveling */ | |
1057 | err = ensure_wear_leveling(ubi); | |
1058 | return err; | |
1059 | } | |
1060 | ||
8d2d4011 | 1061 | ubi_err("failed to erase PEB %d, error %d", pnum, err); |
801c135c | 1062 | kfree(wl_wrk); |
06b68ba1 | 1063 | kmem_cache_free(ubi_wl_entry_slab, e); |
801c135c | 1064 | |
784c1454 AB |
1065 | if (err == -EINTR || err == -ENOMEM || err == -EAGAIN || |
1066 | err == -EBUSY) { | |
1067 | int err1; | |
1068 | ||
1069 | /* Re-schedule the LEB for erasure */ | |
1070 | err1 = schedule_erase(ubi, e, 0); | |
1071 | if (err1) { | |
1072 | err = err1; | |
1073 | goto out_ro; | |
1074 | } | |
1075 | return err; | |
1076 | } else if (err != -EIO) { | |
801c135c AB |
1077 | /* |
1078 | * If this is not %-EIO, we have no idea what to do. Scheduling | |
1079 | * this physical eraseblock for erasure again would cause | |
1080 | * errors again and again. Well, lets switch to RO mode. | |
1081 | */ | |
784c1454 | 1082 | goto out_ro; |
801c135c AB |
1083 | } |
1084 | ||
1085 | /* It is %-EIO, the PEB went bad */ | |
1086 | ||
1087 | if (!ubi->bad_allowed) { | |
1088 | ubi_err("bad physical eraseblock %d detected", pnum); | |
784c1454 AB |
1089 | goto out_ro; |
1090 | } | |
801c135c | 1091 | |
784c1454 AB |
1092 | spin_lock(&ubi->volumes_lock); |
1093 | need = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs + 1; | |
1094 | if (need > 0) { | |
1095 | need = ubi->avail_pebs >= need ? need : ubi->avail_pebs; | |
1096 | ubi->avail_pebs -= need; | |
1097 | ubi->rsvd_pebs += need; | |
1098 | ubi->beb_rsvd_pebs += need; | |
1099 | if (need > 0) | |
1100 | ubi_msg("reserve more %d PEBs", need); | |
1101 | } | |
801c135c | 1102 | |
784c1454 | 1103 | if (ubi->beb_rsvd_pebs == 0) { |
801c135c | 1104 | spin_unlock(&ubi->volumes_lock); |
784c1454 AB |
1105 | ubi_err("no reserved physical eraseblocks"); |
1106 | goto out_ro; | |
1107 | } | |
801c135c | 1108 | |
784c1454 AB |
1109 | spin_unlock(&ubi->volumes_lock); |
1110 | ubi_msg("mark PEB %d as bad", pnum); | |
801c135c | 1111 | |
784c1454 AB |
1112 | err = ubi_io_mark_bad(ubi, pnum); |
1113 | if (err) | |
1114 | goto out_ro; | |
1115 | ||
1116 | spin_lock(&ubi->volumes_lock); | |
1117 | ubi->beb_rsvd_pebs -= 1; | |
1118 | ubi->bad_peb_count += 1; | |
1119 | ubi->good_peb_count -= 1; | |
1120 | ubi_calculate_reserved(ubi); | |
1121 | if (ubi->beb_rsvd_pebs == 0) | |
1122 | ubi_warn("last PEB from the reserved pool was used"); | |
1123 | spin_unlock(&ubi->volumes_lock); | |
1124 | ||
1125 | return err; | |
801c135c | 1126 | |
784c1454 AB |
1127 | out_ro: |
1128 | ubi_ro_mode(ubi); | |
801c135c AB |
1129 | return err; |
1130 | } | |
1131 | ||
1132 | /** | |
43f9b25a | 1133 | * ubi_wl_put_peb - return a physical eraseblock to the wear-leveling unit. |
801c135c AB |
1134 | * @ubi: UBI device description object |
1135 | * @pnum: physical eraseblock to return | |
1136 | * @torture: if this physical eraseblock has to be tortured | |
1137 | * | |
1138 | * This function is called to return physical eraseblock @pnum to the pool of | |
1139 | * free physical eraseblocks. The @torture flag has to be set if an I/O error | |
1140 | * occurred to this @pnum and it has to be tested. This function returns zero | |
43f9b25a | 1141 | * in case of success, and a negative error code in case of failure. |
801c135c AB |
1142 | */ |
1143 | int ubi_wl_put_peb(struct ubi_device *ubi, int pnum, int torture) | |
1144 | { | |
1145 | int err; | |
1146 | struct ubi_wl_entry *e; | |
1147 | ||
1148 | dbg_wl("PEB %d", pnum); | |
1149 | ubi_assert(pnum >= 0); | |
1150 | ubi_assert(pnum < ubi->peb_count); | |
1151 | ||
43f9b25a | 1152 | retry: |
801c135c | 1153 | spin_lock(&ubi->wl_lock); |
801c135c AB |
1154 | e = ubi->lookuptbl[pnum]; |
1155 | if (e == ubi->move_from) { | |
1156 | /* | |
1157 | * User is putting the physical eraseblock which was selected to | |
1158 | * be moved. It will be scheduled for erasure in the | |
1159 | * wear-leveling worker. | |
1160 | */ | |
43f9b25a | 1161 | dbg_wl("PEB %d is being moved, wait", pnum); |
801c135c | 1162 | spin_unlock(&ubi->wl_lock); |
43f9b25a AB |
1163 | |
1164 | /* Wait for the WL worker by taking the @ubi->move_mutex */ | |
1165 | mutex_lock(&ubi->move_mutex); | |
1166 | mutex_unlock(&ubi->move_mutex); | |
1167 | goto retry; | |
801c135c AB |
1168 | } else if (e == ubi->move_to) { |
1169 | /* | |
1170 | * User is putting the physical eraseblock which was selected | |
1171 | * as the target the data is moved to. It may happen if the EBA | |
d2c46855 AB |
1172 | * unit already re-mapped the LEB in 'ubi_eba_copy_leb()' but |
1173 | * the WL unit has not put the PEB to the "used" tree yet, but | |
1174 | * it is about to do this. So we just set a flag which will | |
1175 | * tell the WL worker that the PEB is not needed anymore and | |
1176 | * should be sheduled for erasure. | |
801c135c AB |
1177 | */ |
1178 | dbg_wl("PEB %d is the target of data moving", pnum); | |
1179 | ubi_assert(!ubi->move_to_put); | |
1180 | ubi->move_to_put = 1; | |
1181 | spin_unlock(&ubi->wl_lock); | |
1182 | return 0; | |
1183 | } else { | |
5abde384 AB |
1184 | if (in_wl_tree(e, &ubi->used)) { |
1185 | paranoid_check_in_wl_tree(e, &ubi->used); | |
1186 | rb_erase(&e->rb, &ubi->used); | |
1187 | } else if (in_wl_tree(e, &ubi->scrub)) { | |
1188 | paranoid_check_in_wl_tree(e, &ubi->scrub); | |
1189 | rb_erase(&e->rb, &ubi->scrub); | |
43f9b25a AB |
1190 | } else { |
1191 | err = prot_tree_del(ubi, e->pnum); | |
1192 | if (err) { | |
1193 | ubi_err("PEB %d not found", pnum); | |
1194 | ubi_ro_mode(ubi); | |
1195 | spin_unlock(&ubi->wl_lock); | |
1196 | return err; | |
1197 | } | |
1198 | } | |
801c135c AB |
1199 | } |
1200 | spin_unlock(&ubi->wl_lock); | |
1201 | ||
1202 | err = schedule_erase(ubi, e, torture); | |
1203 | if (err) { | |
1204 | spin_lock(&ubi->wl_lock); | |
5abde384 | 1205 | wl_tree_add(e, &ubi->used); |
801c135c AB |
1206 | spin_unlock(&ubi->wl_lock); |
1207 | } | |
1208 | ||
1209 | return err; | |
1210 | } | |
1211 | ||
1212 | /** | |
1213 | * ubi_wl_scrub_peb - schedule a physical eraseblock for scrubbing. | |
1214 | * @ubi: UBI device description object | |
1215 | * @pnum: the physical eraseblock to schedule | |
1216 | * | |
1217 | * If a bit-flip in a physical eraseblock is detected, this physical eraseblock | |
1218 | * needs scrubbing. This function schedules a physical eraseblock for | |
1219 | * scrubbing which is done in background. This function returns zero in case of | |
1220 | * success and a negative error code in case of failure. | |
1221 | */ | |
1222 | int ubi_wl_scrub_peb(struct ubi_device *ubi, int pnum) | |
1223 | { | |
1224 | struct ubi_wl_entry *e; | |
1225 | ||
1226 | ubi_msg("schedule PEB %d for scrubbing", pnum); | |
1227 | ||
1228 | retry: | |
1229 | spin_lock(&ubi->wl_lock); | |
1230 | e = ubi->lookuptbl[pnum]; | |
1231 | if (e == ubi->move_from || in_wl_tree(e, &ubi->scrub)) { | |
1232 | spin_unlock(&ubi->wl_lock); | |
1233 | return 0; | |
1234 | } | |
1235 | ||
1236 | if (e == ubi->move_to) { | |
1237 | /* | |
1238 | * This physical eraseblock was used to move data to. The data | |
1239 | * was moved but the PEB was not yet inserted to the proper | |
1240 | * tree. We should just wait a little and let the WL worker | |
1241 | * proceed. | |
1242 | */ | |
1243 | spin_unlock(&ubi->wl_lock); | |
1244 | dbg_wl("the PEB %d is not in proper tree, retry", pnum); | |
1245 | yield(); | |
1246 | goto retry; | |
1247 | } | |
1248 | ||
5abde384 AB |
1249 | if (in_wl_tree(e, &ubi->used)) { |
1250 | paranoid_check_in_wl_tree(e, &ubi->used); | |
1251 | rb_erase(&e->rb, &ubi->used); | |
43f9b25a AB |
1252 | } else { |
1253 | int err; | |
1254 | ||
1255 | err = prot_tree_del(ubi, e->pnum); | |
1256 | if (err) { | |
1257 | ubi_err("PEB %d not found", pnum); | |
1258 | ubi_ro_mode(ubi); | |
1259 | spin_unlock(&ubi->wl_lock); | |
1260 | return err; | |
1261 | } | |
1262 | } | |
801c135c | 1263 | |
5abde384 | 1264 | wl_tree_add(e, &ubi->scrub); |
801c135c AB |
1265 | spin_unlock(&ubi->wl_lock); |
1266 | ||
1267 | /* | |
1268 | * Technically scrubbing is the same as wear-leveling, so it is done | |
1269 | * by the WL worker. | |
1270 | */ | |
1271 | return ensure_wear_leveling(ubi); | |
1272 | } | |
1273 | ||
1274 | /** | |
1275 | * ubi_wl_flush - flush all pending works. | |
1276 | * @ubi: UBI device description object | |
1277 | * | |
1278 | * This function returns zero in case of success and a negative error code in | |
1279 | * case of failure. | |
1280 | */ | |
1281 | int ubi_wl_flush(struct ubi_device *ubi) | |
1282 | { | |
1283 | int err, pending_count; | |
1284 | ||
1285 | pending_count = ubi->works_count; | |
1286 | ||
1287 | dbg_wl("flush (%d pending works)", pending_count); | |
1288 | ||
1289 | /* | |
1290 | * Erase while the pending works queue is not empty, but not more then | |
1291 | * the number of currently pending works. | |
1292 | */ | |
1293 | while (pending_count-- > 0) { | |
1294 | err = do_work(ubi); | |
1295 | if (err) | |
1296 | return err; | |
1297 | } | |
1298 | ||
1299 | return 0; | |
1300 | } | |
1301 | ||
1302 | /** | |
1303 | * tree_destroy - destroy an RB-tree. | |
1304 | * @root: the root of the tree to destroy | |
1305 | */ | |
1306 | static void tree_destroy(struct rb_root *root) | |
1307 | { | |
1308 | struct rb_node *rb; | |
1309 | struct ubi_wl_entry *e; | |
1310 | ||
1311 | rb = root->rb_node; | |
1312 | while (rb) { | |
1313 | if (rb->rb_left) | |
1314 | rb = rb->rb_left; | |
1315 | else if (rb->rb_right) | |
1316 | rb = rb->rb_right; | |
1317 | else { | |
1318 | e = rb_entry(rb, struct ubi_wl_entry, rb); | |
1319 | ||
1320 | rb = rb_parent(rb); | |
1321 | if (rb) { | |
1322 | if (rb->rb_left == &e->rb) | |
1323 | rb->rb_left = NULL; | |
1324 | else | |
1325 | rb->rb_right = NULL; | |
1326 | } | |
1327 | ||
06b68ba1 | 1328 | kmem_cache_free(ubi_wl_entry_slab, e); |
801c135c AB |
1329 | } |
1330 | } | |
1331 | } | |
1332 | ||
1333 | /** | |
1334 | * ubi_thread - UBI background thread. | |
1335 | * @u: the UBI device description object pointer | |
1336 | */ | |
1337 | static int ubi_thread(void *u) | |
1338 | { | |
1339 | int failures = 0; | |
1340 | struct ubi_device *ubi = u; | |
1341 | ||
1342 | ubi_msg("background thread \"%s\" started, PID %d", | |
ba25f9dc | 1343 | ubi->bgt_name, task_pid_nr(current)); |
801c135c | 1344 | |
83144186 | 1345 | set_freezable(); |
801c135c AB |
1346 | for (;;) { |
1347 | int err; | |
1348 | ||
1349 | if (kthread_should_stop()) | |
1350 | goto out; | |
1351 | ||
1352 | if (try_to_freeze()) | |
1353 | continue; | |
1354 | ||
1355 | spin_lock(&ubi->wl_lock); | |
1356 | if (list_empty(&ubi->works) || ubi->ro_mode || | |
1357 | !ubi->thread_enabled) { | |
1358 | set_current_state(TASK_INTERRUPTIBLE); | |
1359 | spin_unlock(&ubi->wl_lock); | |
1360 | schedule(); | |
1361 | continue; | |
1362 | } | |
1363 | spin_unlock(&ubi->wl_lock); | |
1364 | ||
1365 | err = do_work(ubi); | |
1366 | if (err) { | |
1367 | ubi_err("%s: work failed with error code %d", | |
1368 | ubi->bgt_name, err); | |
1369 | if (failures++ > WL_MAX_FAILURES) { | |
1370 | /* | |
1371 | * Too many failures, disable the thread and | |
1372 | * switch to read-only mode. | |
1373 | */ | |
1374 | ubi_msg("%s: %d consecutive failures", | |
1375 | ubi->bgt_name, WL_MAX_FAILURES); | |
1376 | ubi_ro_mode(ubi); | |
1377 | break; | |
1378 | } | |
1379 | } else | |
1380 | failures = 0; | |
1381 | ||
1382 | cond_resched(); | |
1383 | } | |
1384 | ||
1385 | out: | |
1386 | dbg_wl("background thread \"%s\" is killed", ubi->bgt_name); | |
1387 | return 0; | |
1388 | } | |
1389 | ||
1390 | /** | |
1391 | * cancel_pending - cancel all pending works. | |
1392 | * @ubi: UBI device description object | |
1393 | */ | |
1394 | static void cancel_pending(struct ubi_device *ubi) | |
1395 | { | |
1396 | while (!list_empty(&ubi->works)) { | |
1397 | struct ubi_work *wrk; | |
1398 | ||
1399 | wrk = list_entry(ubi->works.next, struct ubi_work, list); | |
1400 | list_del(&wrk->list); | |
1401 | wrk->func(ubi, wrk, 1); | |
1402 | ubi->works_count -= 1; | |
1403 | ubi_assert(ubi->works_count >= 0); | |
1404 | } | |
1405 | } | |
1406 | ||
1407 | /** | |
1408 | * ubi_wl_init_scan - initialize the wear-leveling unit using scanning | |
1409 | * information. | |
1410 | * @ubi: UBI device description object | |
1411 | * @si: scanning information | |
1412 | * | |
1413 | * This function returns zero in case of success, and a negative error code in | |
1414 | * case of failure. | |
1415 | */ | |
1416 | int ubi_wl_init_scan(struct ubi_device *ubi, struct ubi_scan_info *si) | |
1417 | { | |
1418 | int err; | |
1419 | struct rb_node *rb1, *rb2; | |
1420 | struct ubi_scan_volume *sv; | |
1421 | struct ubi_scan_leb *seb, *tmp; | |
1422 | struct ubi_wl_entry *e; | |
1423 | ||
1424 | ||
1425 | ubi->used = ubi->free = ubi->scrub = RB_ROOT; | |
1426 | ubi->prot.pnum = ubi->prot.aec = RB_ROOT; | |
1427 | spin_lock_init(&ubi->wl_lock); | |
43f9b25a | 1428 | mutex_init(&ubi->move_mutex); |
801c135c AB |
1429 | ubi->max_ec = si->max_ec; |
1430 | INIT_LIST_HEAD(&ubi->works); | |
1431 | ||
1432 | sprintf(ubi->bgt_name, UBI_BGT_NAME_PATTERN, ubi->ubi_num); | |
1433 | ||
1434 | ubi->bgt_thread = kthread_create(ubi_thread, ubi, ubi->bgt_name); | |
1435 | if (IS_ERR(ubi->bgt_thread)) { | |
1436 | err = PTR_ERR(ubi->bgt_thread); | |
1437 | ubi_err("cannot spawn \"%s\", error %d", ubi->bgt_name, | |
1438 | err); | |
1439 | return err; | |
1440 | } | |
1441 | ||
801c135c AB |
1442 | err = -ENOMEM; |
1443 | ubi->lookuptbl = kzalloc(ubi->peb_count * sizeof(void *), GFP_KERNEL); | |
1444 | if (!ubi->lookuptbl) | |
1445 | goto out_free; | |
1446 | ||
1447 | list_for_each_entry_safe(seb, tmp, &si->erase, u.list) { | |
1448 | cond_resched(); | |
1449 | ||
06b68ba1 | 1450 | e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL); |
801c135c AB |
1451 | if (!e) |
1452 | goto out_free; | |
1453 | ||
1454 | e->pnum = seb->pnum; | |
1455 | e->ec = seb->ec; | |
1456 | ubi->lookuptbl[e->pnum] = e; | |
1457 | if (schedule_erase(ubi, e, 0)) { | |
06b68ba1 | 1458 | kmem_cache_free(ubi_wl_entry_slab, e); |
801c135c AB |
1459 | goto out_free; |
1460 | } | |
1461 | } | |
1462 | ||
1463 | list_for_each_entry(seb, &si->free, u.list) { | |
1464 | cond_resched(); | |
1465 | ||
06b68ba1 | 1466 | e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL); |
801c135c AB |
1467 | if (!e) |
1468 | goto out_free; | |
1469 | ||
1470 | e->pnum = seb->pnum; | |
1471 | e->ec = seb->ec; | |
1472 | ubi_assert(e->ec >= 0); | |
5abde384 | 1473 | wl_tree_add(e, &ubi->free); |
801c135c AB |
1474 | ubi->lookuptbl[e->pnum] = e; |
1475 | } | |
1476 | ||
1477 | list_for_each_entry(seb, &si->corr, u.list) { | |
1478 | cond_resched(); | |
1479 | ||
06b68ba1 | 1480 | e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL); |
801c135c AB |
1481 | if (!e) |
1482 | goto out_free; | |
1483 | ||
1484 | e->pnum = seb->pnum; | |
1485 | e->ec = seb->ec; | |
1486 | ubi->lookuptbl[e->pnum] = e; | |
1487 | if (schedule_erase(ubi, e, 0)) { | |
06b68ba1 | 1488 | kmem_cache_free(ubi_wl_entry_slab, e); |
801c135c AB |
1489 | goto out_free; |
1490 | } | |
1491 | } | |
1492 | ||
1493 | ubi_rb_for_each_entry(rb1, sv, &si->volumes, rb) { | |
1494 | ubi_rb_for_each_entry(rb2, seb, &sv->root, u.rb) { | |
1495 | cond_resched(); | |
1496 | ||
06b68ba1 | 1497 | e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL); |
801c135c AB |
1498 | if (!e) |
1499 | goto out_free; | |
1500 | ||
1501 | e->pnum = seb->pnum; | |
1502 | e->ec = seb->ec; | |
1503 | ubi->lookuptbl[e->pnum] = e; | |
1504 | if (!seb->scrub) { | |
1505 | dbg_wl("add PEB %d EC %d to the used tree", | |
1506 | e->pnum, e->ec); | |
5abde384 | 1507 | wl_tree_add(e, &ubi->used); |
801c135c AB |
1508 | } else { |
1509 | dbg_wl("add PEB %d EC %d to the scrub tree", | |
1510 | e->pnum, e->ec); | |
5abde384 | 1511 | wl_tree_add(e, &ubi->scrub); |
801c135c AB |
1512 | } |
1513 | } | |
1514 | } | |
1515 | ||
5abde384 | 1516 | if (ubi->avail_pebs < WL_RESERVED_PEBS) { |
801c135c AB |
1517 | ubi_err("no enough physical eraseblocks (%d, need %d)", |
1518 | ubi->avail_pebs, WL_RESERVED_PEBS); | |
1519 | goto out_free; | |
1520 | } | |
1521 | ubi->avail_pebs -= WL_RESERVED_PEBS; | |
1522 | ubi->rsvd_pebs += WL_RESERVED_PEBS; | |
1523 | ||
1524 | /* Schedule wear-leveling if needed */ | |
1525 | err = ensure_wear_leveling(ubi); | |
1526 | if (err) | |
1527 | goto out_free; | |
1528 | ||
1529 | return 0; | |
1530 | ||
1531 | out_free: | |
1532 | cancel_pending(ubi); | |
1533 | tree_destroy(&ubi->used); | |
1534 | tree_destroy(&ubi->free); | |
1535 | tree_destroy(&ubi->scrub); | |
1536 | kfree(ubi->lookuptbl); | |
801c135c AB |
1537 | return err; |
1538 | } | |
1539 | ||
1540 | /** | |
1541 | * protection_trees_destroy - destroy the protection RB-trees. | |
1542 | * @ubi: UBI device description object | |
1543 | */ | |
1544 | static void protection_trees_destroy(struct ubi_device *ubi) | |
1545 | { | |
1546 | struct rb_node *rb; | |
1547 | struct ubi_wl_prot_entry *pe; | |
1548 | ||
1549 | rb = ubi->prot.aec.rb_node; | |
1550 | while (rb) { | |
1551 | if (rb->rb_left) | |
1552 | rb = rb->rb_left; | |
1553 | else if (rb->rb_right) | |
1554 | rb = rb->rb_right; | |
1555 | else { | |
1556 | pe = rb_entry(rb, struct ubi_wl_prot_entry, rb_aec); | |
1557 | ||
1558 | rb = rb_parent(rb); | |
1559 | if (rb) { | |
1560 | if (rb->rb_left == &pe->rb_aec) | |
1561 | rb->rb_left = NULL; | |
1562 | else | |
1563 | rb->rb_right = NULL; | |
1564 | } | |
1565 | ||
06b68ba1 | 1566 | kmem_cache_free(ubi_wl_entry_slab, pe->e); |
801c135c AB |
1567 | kfree(pe); |
1568 | } | |
1569 | } | |
1570 | } | |
1571 | ||
1572 | /** | |
1573 | * ubi_wl_close - close the wear-leveling unit. | |
1574 | * @ubi: UBI device description object | |
1575 | */ | |
1576 | void ubi_wl_close(struct ubi_device *ubi) | |
1577 | { | |
1578 | dbg_wl("disable \"%s\"", ubi->bgt_name); | |
1579 | if (ubi->bgt_thread) | |
1580 | kthread_stop(ubi->bgt_thread); | |
1581 | ||
1582 | dbg_wl("close the UBI wear-leveling unit"); | |
1583 | ||
1584 | cancel_pending(ubi); | |
1585 | protection_trees_destroy(ubi); | |
1586 | tree_destroy(&ubi->used); | |
1587 | tree_destroy(&ubi->free); | |
1588 | tree_destroy(&ubi->scrub); | |
1589 | kfree(ubi->lookuptbl); | |
801c135c AB |
1590 | } |
1591 | ||
1592 | #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID | |
1593 | ||
1594 | /** | |
1595 | * paranoid_check_ec - make sure that the erase counter of a physical eraseblock | |
1596 | * is correct. | |
1597 | * @ubi: UBI device description object | |
1598 | * @pnum: the physical eraseblock number to check | |
1599 | * @ec: the erase counter to check | |
1600 | * | |
1601 | * This function returns zero if the erase counter of physical eraseblock @pnum | |
1602 | * is equivalent to @ec, %1 if not, and a negative error code if an error | |
1603 | * occurred. | |
1604 | */ | |
e88d6e10 | 1605 | static int paranoid_check_ec(struct ubi_device *ubi, int pnum, int ec) |
801c135c AB |
1606 | { |
1607 | int err; | |
1608 | long long read_ec; | |
1609 | struct ubi_ec_hdr *ec_hdr; | |
1610 | ||
33818bbb | 1611 | ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_NOFS); |
801c135c AB |
1612 | if (!ec_hdr) |
1613 | return -ENOMEM; | |
1614 | ||
1615 | err = ubi_io_read_ec_hdr(ubi, pnum, ec_hdr, 0); | |
1616 | if (err && err != UBI_IO_BITFLIPS) { | |
1617 | /* The header does not have to exist */ | |
1618 | err = 0; | |
1619 | goto out_free; | |
1620 | } | |
1621 | ||
3261ebd7 | 1622 | read_ec = be64_to_cpu(ec_hdr->ec); |
801c135c AB |
1623 | if (ec != read_ec) { |
1624 | ubi_err("paranoid check failed for PEB %d", pnum); | |
1625 | ubi_err("read EC is %lld, should be %d", read_ec, ec); | |
1626 | ubi_dbg_dump_stack(); | |
1627 | err = 1; | |
1628 | } else | |
1629 | err = 0; | |
1630 | ||
1631 | out_free: | |
1632 | kfree(ec_hdr); | |
1633 | return err; | |
1634 | } | |
1635 | ||
1636 | /** | |
1637 | * paranoid_check_in_wl_tree - make sure that a wear-leveling entry is present | |
1638 | * in a WL RB-tree. | |
1639 | * @e: the wear-leveling entry to check | |
1640 | * @root: the root of the tree | |
1641 | * | |
1642 | * This function returns zero if @e is in the @root RB-tree and %1 if it | |
1643 | * is not. | |
1644 | */ | |
1645 | static int paranoid_check_in_wl_tree(struct ubi_wl_entry *e, | |
1646 | struct rb_root *root) | |
1647 | { | |
1648 | if (in_wl_tree(e, root)) | |
1649 | return 0; | |
1650 | ||
1651 | ubi_err("paranoid check failed for PEB %d, EC %d, RB-tree %p ", | |
1652 | e->pnum, e->ec, root); | |
1653 | ubi_dbg_dump_stack(); | |
1654 | return 1; | |
1655 | } | |
1656 | ||
1657 | #endif /* CONFIG_MTD_UBI_DEBUG_PARANOID */ |