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801c135c | 1 | /* |
d99383b0 | 2 | * @ubi: UBI device description object |
801c135c AB |
3 | * Copyright (c) International Business Machines Corp., 2006 |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License as published by | |
7 | * the Free Software Foundation; either version 2 of the License, or | |
8 | * (at your option) any later version. | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See | |
13 | * the GNU General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License | |
16 | * along with this program; if not, write to the Free Software | |
17 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
18 | * | |
19 | * Authors: Artem Bityutskiy (Битюцкий Артём), Thomas Gleixner | |
20 | */ | |
21 | ||
22 | /* | |
85c6e6e2 | 23 | * UBI wear-leveling sub-system. |
801c135c | 24 | * |
85c6e6e2 | 25 | * This sub-system is responsible for wear-leveling. It works in terms of |
7b6c32da | 26 | * physical eraseblocks and erase counters and knows nothing about logical |
85c6e6e2 AB |
27 | * eraseblocks, volumes, etc. From this sub-system's perspective all physical |
28 | * eraseblocks are of two types - used and free. Used physical eraseblocks are | |
29 | * those that were "get" by the 'ubi_wl_get_peb()' function, and free physical | |
30 | * eraseblocks are those that were put by the 'ubi_wl_put_peb()' function. | |
801c135c AB |
31 | * |
32 | * Physical eraseblocks returned by 'ubi_wl_get_peb()' have only erase counter | |
85c6e6e2 | 33 | * header. The rest of the physical eraseblock contains only %0xFF bytes. |
801c135c | 34 | * |
85c6e6e2 | 35 | * When physical eraseblocks are returned to the WL sub-system by means of the |
801c135c AB |
36 | * 'ubi_wl_put_peb()' function, they are scheduled for erasure. The erasure is |
37 | * done asynchronously in context of the per-UBI device background thread, | |
85c6e6e2 | 38 | * which is also managed by the WL sub-system. |
801c135c AB |
39 | * |
40 | * The wear-leveling is ensured by means of moving the contents of used | |
41 | * physical eraseblocks with low erase counter to free physical eraseblocks | |
42 | * with high erase counter. | |
43 | * | |
85c6e6e2 AB |
44 | * If the WL sub-system fails to erase a physical eraseblock, it marks it as |
45 | * bad. | |
801c135c | 46 | * |
85c6e6e2 AB |
47 | * This sub-system is also responsible for scrubbing. If a bit-flip is detected |
48 | * in a physical eraseblock, it has to be moved. Technically this is the same | |
49 | * as moving it for wear-leveling reasons. | |
801c135c | 50 | * |
85c6e6e2 AB |
51 | * As it was said, for the UBI sub-system all physical eraseblocks are either |
52 | * "free" or "used". Free eraseblock are kept in the @wl->free RB-tree, while | |
b86a2c56 AB |
53 | * used eraseblocks are kept in @wl->used, @wl->erroneous, or @wl->scrub |
54 | * RB-trees, as well as (temporarily) in the @wl->pq queue. | |
7b6c32da XX |
55 | * |
56 | * When the WL sub-system returns a physical eraseblock, the physical | |
57 | * eraseblock is protected from being moved for some "time". For this reason, | |
58 | * the physical eraseblock is not directly moved from the @wl->free tree to the | |
59 | * @wl->used tree. There is a protection queue in between where this | |
60 | * physical eraseblock is temporarily stored (@wl->pq). | |
61 | * | |
62 | * All this protection stuff is needed because: | |
63 | * o we don't want to move physical eraseblocks just after we have given them | |
64 | * to the user; instead, we first want to let users fill them up with data; | |
65 | * | |
66 | * o there is a chance that the user will put the physical eraseblock very | |
44156267 | 67 | * soon, so it makes sense not to move it for some time, but wait. |
7b6c32da XX |
68 | * |
69 | * Physical eraseblocks stay protected only for limited time. But the "time" is | |
70 | * measured in erase cycles in this case. This is implemented with help of the | |
71 | * protection queue. Eraseblocks are put to the tail of this queue when they | |
72 | * are returned by the 'ubi_wl_get_peb()', and eraseblocks are removed from the | |
73 | * head of the queue on each erase operation (for any eraseblock). So the | |
74 | * length of the queue defines how may (global) erase cycles PEBs are protected. | |
75 | * | |
76 | * To put it differently, each physical eraseblock has 2 main states: free and | |
77 | * used. The former state corresponds to the @wl->free tree. The latter state | |
78 | * is split up on several sub-states: | |
79 | * o the WL movement is allowed (@wl->used tree); | |
815bc5f8 | 80 | * o the WL movement is disallowed (@wl->erroneous) because the PEB is |
b86a2c56 | 81 | * erroneous - e.g., there was a read error; |
7b6c32da XX |
82 | * o the WL movement is temporarily prohibited (@wl->pq queue); |
83 | * o scrubbing is needed (@wl->scrub tree). | |
84 | * | |
85 | * Depending on the sub-state, wear-leveling entries of the used physical | |
86 | * eraseblocks may be kept in one of those structures. | |
801c135c AB |
87 | * |
88 | * Note, in this implementation, we keep a small in-RAM object for each physical | |
89 | * eraseblock. This is surely not a scalable solution. But it appears to be good | |
90 | * enough for moderately large flashes and it is simple. In future, one may | |
85c6e6e2 | 91 | * re-work this sub-system and make it more scalable. |
801c135c | 92 | * |
85c6e6e2 AB |
93 | * At the moment this sub-system does not utilize the sequence number, which |
94 | * was introduced relatively recently. But it would be wise to do this because | |
95 | * the sequence number of a logical eraseblock characterizes how old is it. For | |
801c135c AB |
96 | * example, when we move a PEB with low erase counter, and we need to pick the |
97 | * target PEB, we pick a PEB with the highest EC if our PEB is "old" and we | |
98 | * pick target PEB with an average EC if our PEB is not very "old". This is a | |
85c6e6e2 | 99 | * room for future re-works of the WL sub-system. |
801c135c AB |
100 | */ |
101 | ||
102 | #include <linux/slab.h> | |
103 | #include <linux/crc32.h> | |
104 | #include <linux/freezer.h> | |
105 | #include <linux/kthread.h> | |
106 | #include "ubi.h" | |
107 | ||
108 | /* Number of physical eraseblocks reserved for wear-leveling purposes */ | |
109 | #define WL_RESERVED_PEBS 1 | |
110 | ||
801c135c AB |
111 | /* |
112 | * Maximum difference between two erase counters. If this threshold is | |
85c6e6e2 AB |
113 | * exceeded, the WL sub-system starts moving data from used physical |
114 | * eraseblocks with low erase counter to free physical eraseblocks with high | |
115 | * erase counter. | |
801c135c AB |
116 | */ |
117 | #define UBI_WL_THRESHOLD CONFIG_MTD_UBI_WL_THRESHOLD | |
118 | ||
119 | /* | |
85c6e6e2 | 120 | * When a physical eraseblock is moved, the WL sub-system has to pick the target |
801c135c AB |
121 | * physical eraseblock to move to. The simplest way would be just to pick the |
122 | * one with the highest erase counter. But in certain workloads this could lead | |
123 | * to an unlimited wear of one or few physical eraseblock. Indeed, imagine a | |
124 | * situation when the picked physical eraseblock is constantly erased after the | |
125 | * data is written to it. So, we have a constant which limits the highest erase | |
85c6e6e2 | 126 | * counter of the free physical eraseblock to pick. Namely, the WL sub-system |
025dfdaf | 127 | * does not pick eraseblocks with erase counter greater than the lowest erase |
801c135c AB |
128 | * counter plus %WL_FREE_MAX_DIFF. |
129 | */ | |
130 | #define WL_FREE_MAX_DIFF (2*UBI_WL_THRESHOLD) | |
131 | ||
132 | /* | |
133 | * Maximum number of consecutive background thread failures which is enough to | |
134 | * switch to read-only mode. | |
135 | */ | |
136 | #define WL_MAX_FAILURES 32 | |
137 | ||
7bf523ae AB |
138 | static int self_check_ec(struct ubi_device *ubi, int pnum, int ec); |
139 | static int self_check_in_wl_tree(const struct ubi_device *ubi, | |
140 | struct ubi_wl_entry *e, struct rb_root *root); | |
141 | static int self_check_in_pq(const struct ubi_device *ubi, | |
142 | struct ubi_wl_entry *e); | |
801c135c | 143 | |
8199b901 RW |
144 | #ifdef CONFIG_MTD_UBI_FASTMAP |
145 | /** | |
146 | * update_fastmap_work_fn - calls ubi_update_fastmap from a work queue | |
147 | * @wrk: the work description object | |
148 | */ | |
149 | static void update_fastmap_work_fn(struct work_struct *wrk) | |
150 | { | |
151 | struct ubi_device *ubi = container_of(wrk, struct ubi_device, fm_work); | |
152 | ubi_update_fastmap(ubi); | |
153 | } | |
154 | ||
155 | /** | |
156 | * ubi_ubi_is_fm_block - returns 1 if a PEB is currently used in a fastmap. | |
157 | * @ubi: UBI device description object | |
158 | * @pnum: the to be checked PEB | |
159 | */ | |
160 | static int ubi_is_fm_block(struct ubi_device *ubi, int pnum) | |
161 | { | |
162 | int i; | |
163 | ||
164 | if (!ubi->fm) | |
165 | return 0; | |
166 | ||
167 | for (i = 0; i < ubi->fm->used_blocks; i++) | |
168 | if (ubi->fm->e[i]->pnum == pnum) | |
169 | return 1; | |
170 | ||
171 | return 0; | |
172 | } | |
173 | #else | |
174 | static int ubi_is_fm_block(struct ubi_device *ubi, int pnum) | |
175 | { | |
176 | return 0; | |
177 | } | |
178 | #endif | |
179 | ||
801c135c AB |
180 | /** |
181 | * wl_tree_add - add a wear-leveling entry to a WL RB-tree. | |
182 | * @e: the wear-leveling entry to add | |
183 | * @root: the root of the tree | |
184 | * | |
185 | * Note, we use (erase counter, physical eraseblock number) pairs as keys in | |
186 | * the @ubi->used and @ubi->free RB-trees. | |
187 | */ | |
188 | static void wl_tree_add(struct ubi_wl_entry *e, struct rb_root *root) | |
189 | { | |
190 | struct rb_node **p, *parent = NULL; | |
191 | ||
192 | p = &root->rb_node; | |
193 | while (*p) { | |
194 | struct ubi_wl_entry *e1; | |
195 | ||
196 | parent = *p; | |
23553b2c | 197 | e1 = rb_entry(parent, struct ubi_wl_entry, u.rb); |
801c135c AB |
198 | |
199 | if (e->ec < e1->ec) | |
200 | p = &(*p)->rb_left; | |
201 | else if (e->ec > e1->ec) | |
202 | p = &(*p)->rb_right; | |
203 | else { | |
204 | ubi_assert(e->pnum != e1->pnum); | |
205 | if (e->pnum < e1->pnum) | |
206 | p = &(*p)->rb_left; | |
207 | else | |
208 | p = &(*p)->rb_right; | |
209 | } | |
210 | } | |
211 | ||
23553b2c XX |
212 | rb_link_node(&e->u.rb, parent, p); |
213 | rb_insert_color(&e->u.rb, root); | |
801c135c AB |
214 | } |
215 | ||
801c135c AB |
216 | /** |
217 | * do_work - do one pending work. | |
218 | * @ubi: UBI device description object | |
219 | * | |
220 | * This function returns zero in case of success and a negative error code in | |
221 | * case of failure. | |
222 | */ | |
223 | static int do_work(struct ubi_device *ubi) | |
224 | { | |
225 | int err; | |
226 | struct ubi_work *wrk; | |
227 | ||
43f9b25a AB |
228 | cond_resched(); |
229 | ||
593dd33c AB |
230 | /* |
231 | * @ubi->work_sem is used to synchronize with the workers. Workers take | |
232 | * it in read mode, so many of them may be doing works at a time. But | |
233 | * the queue flush code has to be sure the whole queue of works is | |
234 | * done, and it takes the mutex in write mode. | |
235 | */ | |
236 | down_read(&ubi->work_sem); | |
801c135c | 237 | spin_lock(&ubi->wl_lock); |
801c135c AB |
238 | if (list_empty(&ubi->works)) { |
239 | spin_unlock(&ubi->wl_lock); | |
593dd33c | 240 | up_read(&ubi->work_sem); |
801c135c AB |
241 | return 0; |
242 | } | |
243 | ||
244 | wrk = list_entry(ubi->works.next, struct ubi_work, list); | |
245 | list_del(&wrk->list); | |
16f557ec AB |
246 | ubi->works_count -= 1; |
247 | ubi_assert(ubi->works_count >= 0); | |
801c135c AB |
248 | spin_unlock(&ubi->wl_lock); |
249 | ||
250 | /* | |
251 | * Call the worker function. Do not touch the work structure | |
252 | * after this call as it will have been freed or reused by that | |
253 | * time by the worker function. | |
254 | */ | |
255 | err = wrk->func(ubi, wrk, 0); | |
256 | if (err) | |
257 | ubi_err("work failed with error code %d", err); | |
593dd33c | 258 | up_read(&ubi->work_sem); |
16f557ec | 259 | |
801c135c AB |
260 | return err; |
261 | } | |
262 | ||
263 | /** | |
264 | * produce_free_peb - produce a free physical eraseblock. | |
265 | * @ubi: UBI device description object | |
266 | * | |
267 | * This function tries to make a free PEB by means of synchronous execution of | |
268 | * pending works. This may be needed if, for example the background thread is | |
269 | * disabled. Returns zero in case of success and a negative error code in case | |
270 | * of failure. | |
271 | */ | |
272 | static int produce_free_peb(struct ubi_device *ubi) | |
273 | { | |
274 | int err; | |
275 | ||
5abde384 | 276 | while (!ubi->free.rb_node) { |
801c135c AB |
277 | spin_unlock(&ubi->wl_lock); |
278 | ||
279 | dbg_wl("do one work synchronously"); | |
280 | err = do_work(ubi); | |
801c135c AB |
281 | |
282 | spin_lock(&ubi->wl_lock); | |
8199b901 RW |
283 | if (err) |
284 | return err; | |
801c135c | 285 | } |
801c135c AB |
286 | |
287 | return 0; | |
288 | } | |
289 | ||
290 | /** | |
291 | * in_wl_tree - check if wear-leveling entry is present in a WL RB-tree. | |
292 | * @e: the wear-leveling entry to check | |
293 | * @root: the root of the tree | |
294 | * | |
295 | * This function returns non-zero if @e is in the @root RB-tree and zero if it | |
296 | * is not. | |
297 | */ | |
298 | static int in_wl_tree(struct ubi_wl_entry *e, struct rb_root *root) | |
299 | { | |
300 | struct rb_node *p; | |
301 | ||
302 | p = root->rb_node; | |
303 | while (p) { | |
304 | struct ubi_wl_entry *e1; | |
305 | ||
23553b2c | 306 | e1 = rb_entry(p, struct ubi_wl_entry, u.rb); |
801c135c AB |
307 | |
308 | if (e->pnum == e1->pnum) { | |
309 | ubi_assert(e == e1); | |
310 | return 1; | |
311 | } | |
312 | ||
313 | if (e->ec < e1->ec) | |
314 | p = p->rb_left; | |
315 | else if (e->ec > e1->ec) | |
316 | p = p->rb_right; | |
317 | else { | |
318 | ubi_assert(e->pnum != e1->pnum); | |
319 | if (e->pnum < e1->pnum) | |
320 | p = p->rb_left; | |
321 | else | |
322 | p = p->rb_right; | |
323 | } | |
324 | } | |
325 | ||
326 | return 0; | |
327 | } | |
328 | ||
329 | /** | |
7b6c32da | 330 | * prot_queue_add - add physical eraseblock to the protection queue. |
801c135c AB |
331 | * @ubi: UBI device description object |
332 | * @e: the physical eraseblock to add | |
801c135c | 333 | * |
7b6c32da XX |
334 | * This function adds @e to the tail of the protection queue @ubi->pq, where |
335 | * @e will stay for %UBI_PROT_QUEUE_LEN erase operations and will be | |
336 | * temporarily protected from the wear-leveling worker. Note, @wl->lock has to | |
337 | * be locked. | |
801c135c | 338 | */ |
7b6c32da | 339 | static void prot_queue_add(struct ubi_device *ubi, struct ubi_wl_entry *e) |
801c135c | 340 | { |
7b6c32da | 341 | int pq_tail = ubi->pq_head - 1; |
801c135c | 342 | |
7b6c32da XX |
343 | if (pq_tail < 0) |
344 | pq_tail = UBI_PROT_QUEUE_LEN - 1; | |
345 | ubi_assert(pq_tail >= 0 && pq_tail < UBI_PROT_QUEUE_LEN); | |
346 | list_add_tail(&e->u.list, &ubi->pq[pq_tail]); | |
347 | dbg_wl("added PEB %d EC %d to the protection queue", e->pnum, e->ec); | |
801c135c AB |
348 | } |
349 | ||
350 | /** | |
351 | * find_wl_entry - find wear-leveling entry closest to certain erase counter. | |
8199b901 | 352 | * @ubi: UBI device description object |
801c135c | 353 | * @root: the RB-tree where to look for |
add8287e | 354 | * @diff: maximum possible difference from the smallest erase counter |
801c135c AB |
355 | * |
356 | * This function looks for a wear leveling entry with erase counter closest to | |
add8287e | 357 | * min + @diff, where min is the smallest erase counter. |
801c135c | 358 | */ |
8199b901 RW |
359 | static struct ubi_wl_entry *find_wl_entry(struct ubi_device *ubi, |
360 | struct rb_root *root, int diff) | |
801c135c AB |
361 | { |
362 | struct rb_node *p; | |
8199b901 | 363 | struct ubi_wl_entry *e, *prev_e = NULL; |
add8287e | 364 | int max; |
801c135c | 365 | |
23553b2c | 366 | e = rb_entry(rb_first(root), struct ubi_wl_entry, u.rb); |
add8287e | 367 | max = e->ec + diff; |
801c135c AB |
368 | |
369 | p = root->rb_node; | |
370 | while (p) { | |
371 | struct ubi_wl_entry *e1; | |
372 | ||
23553b2c | 373 | e1 = rb_entry(p, struct ubi_wl_entry, u.rb); |
801c135c AB |
374 | if (e1->ec >= max) |
375 | p = p->rb_left; | |
376 | else { | |
377 | p = p->rb_right; | |
8199b901 | 378 | prev_e = e; |
801c135c AB |
379 | e = e1; |
380 | } | |
381 | } | |
382 | ||
8199b901 RW |
383 | /* If no fastmap has been written and this WL entry can be used |
384 | * as anchor PEB, hold it back and return the second best WL entry | |
385 | * such that fastmap can use the anchor PEB later. */ | |
386 | if (prev_e && !ubi->fm_disabled && | |
387 | !ubi->fm && e->pnum < UBI_FM_MAX_START) | |
388 | return prev_e; | |
389 | ||
801c135c AB |
390 | return e; |
391 | } | |
392 | ||
393 | /** | |
8199b901 RW |
394 | * find_mean_wl_entry - find wear-leveling entry with medium erase counter. |
395 | * @ubi: UBI device description object | |
396 | * @root: the RB-tree where to look for | |
397 | * | |
398 | * This function looks for a wear leveling entry with medium erase counter, | |
399 | * but not greater or equivalent than the lowest erase counter plus | |
400 | * %WL_FREE_MAX_DIFF/2. | |
401 | */ | |
402 | static struct ubi_wl_entry *find_mean_wl_entry(struct ubi_device *ubi, | |
403 | struct rb_root *root) | |
404 | { | |
405 | struct ubi_wl_entry *e, *first, *last; | |
406 | ||
407 | first = rb_entry(rb_first(root), struct ubi_wl_entry, u.rb); | |
408 | last = rb_entry(rb_last(root), struct ubi_wl_entry, u.rb); | |
409 | ||
410 | if (last->ec - first->ec < WL_FREE_MAX_DIFF) { | |
411 | e = rb_entry(root->rb_node, struct ubi_wl_entry, u.rb); | |
412 | ||
413 | #ifdef CONFIG_MTD_UBI_FASTMAP | |
414 | /* If no fastmap has been written and this WL entry can be used | |
415 | * as anchor PEB, hold it back and return the second best | |
416 | * WL entry such that fastmap can use the anchor PEB later. */ | |
417 | if (e && !ubi->fm_disabled && !ubi->fm && | |
418 | e->pnum < UBI_FM_MAX_START) | |
419 | e = rb_entry(rb_next(root->rb_node), | |
420 | struct ubi_wl_entry, u.rb); | |
421 | #endif | |
422 | } else | |
423 | e = find_wl_entry(ubi, root, WL_FREE_MAX_DIFF/2); | |
424 | ||
425 | return e; | |
426 | } | |
427 | ||
428 | #ifdef CONFIG_MTD_UBI_FASTMAP | |
429 | /** | |
430 | * find_anchor_wl_entry - find wear-leveling entry to used as anchor PEB. | |
431 | * @root: the RB-tree where to look for | |
432 | */ | |
433 | static struct ubi_wl_entry *find_anchor_wl_entry(struct rb_root *root) | |
434 | { | |
435 | struct rb_node *p; | |
436 | struct ubi_wl_entry *e, *victim = NULL; | |
437 | int max_ec = UBI_MAX_ERASECOUNTER; | |
438 | ||
439 | ubi_rb_for_each_entry(p, e, root, u.rb) { | |
440 | if (e->pnum < UBI_FM_MAX_START && e->ec < max_ec) { | |
441 | victim = e; | |
442 | max_ec = e->ec; | |
443 | } | |
444 | } | |
445 | ||
446 | return victim; | |
447 | } | |
448 | ||
449 | static int anchor_pebs_avalible(struct rb_root *root) | |
450 | { | |
451 | struct rb_node *p; | |
452 | struct ubi_wl_entry *e; | |
453 | ||
454 | ubi_rb_for_each_entry(p, e, root, u.rb) | |
455 | if (e->pnum < UBI_FM_MAX_START) | |
456 | return 1; | |
457 | ||
458 | return 0; | |
459 | } | |
460 | ||
461 | /** | |
462 | * ubi_wl_get_fm_peb - find a physical erase block with a given maximal number. | |
463 | * @ubi: UBI device description object | |
464 | * @anchor: This PEB will be used as anchor PEB by fastmap | |
465 | * | |
466 | * The function returns a physical erase block with a given maximal number | |
467 | * and removes it from the wl subsystem. | |
468 | * Must be called with wl_lock held! | |
469 | */ | |
470 | struct ubi_wl_entry *ubi_wl_get_fm_peb(struct ubi_device *ubi, int anchor) | |
471 | { | |
472 | struct ubi_wl_entry *e = NULL; | |
473 | ||
474 | if (!ubi->free.rb_node || (ubi->free_count - ubi->beb_rsvd_pebs < 1)) | |
475 | goto out; | |
476 | ||
477 | if (anchor) | |
478 | e = find_anchor_wl_entry(&ubi->free); | |
479 | else | |
480 | e = find_mean_wl_entry(ubi, &ubi->free); | |
481 | ||
482 | if (!e) | |
483 | goto out; | |
484 | ||
485 | self_check_in_wl_tree(ubi, e, &ubi->free); | |
486 | ||
487 | /* remove it from the free list, | |
488 | * the wl subsystem does no longer know this erase block */ | |
489 | rb_erase(&e->u.rb, &ubi->free); | |
490 | ubi->free_count--; | |
491 | out: | |
492 | return e; | |
493 | } | |
494 | #endif | |
495 | ||
496 | /** | |
497 | * __wl_get_peb - get a physical eraseblock. | |
801c135c | 498 | * @ubi: UBI device description object |
801c135c AB |
499 | * |
500 | * This function returns a physical eraseblock in case of success and a | |
501 | * negative error code in case of failure. Might sleep. | |
502 | */ | |
8199b901 | 503 | static int __wl_get_peb(struct ubi_device *ubi) |
801c135c | 504 | { |
7eb3aa65 | 505 | int err; |
8199b901 | 506 | struct ubi_wl_entry *e; |
801c135c | 507 | |
801c135c | 508 | retry: |
5abde384 | 509 | if (!ubi->free.rb_node) { |
801c135c | 510 | if (ubi->works_count == 0) { |
801c135c | 511 | ubi_err("no free eraseblocks"); |
8199b901 | 512 | ubi_assert(list_empty(&ubi->works)); |
801c135c AB |
513 | return -ENOSPC; |
514 | } | |
801c135c AB |
515 | |
516 | err = produce_free_peb(ubi); | |
7b6c32da | 517 | if (err < 0) |
801c135c | 518 | return err; |
801c135c AB |
519 | goto retry; |
520 | } | |
521 | ||
8199b901 RW |
522 | e = find_mean_wl_entry(ubi, &ubi->free); |
523 | if (!e) { | |
524 | ubi_err("no free eraseblocks"); | |
525 | return -ENOSPC; | |
526 | } | |
801c135c | 527 | |
7bf523ae | 528 | self_check_in_wl_tree(ubi, e, &ubi->free); |
7b6c32da | 529 | |
801c135c | 530 | /* |
7b6c32da | 531 | * Move the physical eraseblock to the protection queue where it will |
801c135c AB |
532 | * be protected from being moved for some time. |
533 | */ | |
23553b2c | 534 | rb_erase(&e->u.rb, &ubi->free); |
8199b901 | 535 | ubi->free_count--; |
7b6c32da | 536 | dbg_wl("PEB %d EC %d", e->pnum, e->ec); |
8199b901 RW |
537 | #ifndef CONFIG_MTD_UBI_FASTMAP |
538 | /* We have to enqueue e only if fastmap is disabled, | |
539 | * is fastmap enabled prot_queue_add() will be called by | |
540 | * ubi_wl_get_peb() after removing e from the pool. */ | |
7b6c32da | 541 | prot_queue_add(ubi, e); |
8199b901 | 542 | #endif |
97d6104b AB |
543 | err = ubi_self_check_all_ff(ubi, e->pnum, ubi->vid_hdr_aloffset, |
544 | ubi->peb_size - ubi->vid_hdr_aloffset); | |
40a71a87 | 545 | if (err) { |
1398788f | 546 | ubi_err("new PEB %d does not contain all 0xFF bytes", e->pnum); |
adbf05e3 | 547 | return err; |
40a71a87 AB |
548 | } |
549 | ||
801c135c AB |
550 | return e->pnum; |
551 | } | |
552 | ||
8199b901 RW |
553 | #ifdef CONFIG_MTD_UBI_FASTMAP |
554 | /** | |
555 | * return_unused_pool_pebs - returns unused PEB to the free tree. | |
556 | * @ubi: UBI device description object | |
557 | * @pool: fastmap pool description object | |
558 | */ | |
559 | static void return_unused_pool_pebs(struct ubi_device *ubi, | |
560 | struct ubi_fm_pool *pool) | |
561 | { | |
562 | int i; | |
563 | struct ubi_wl_entry *e; | |
564 | ||
565 | for (i = pool->used; i < pool->size; i++) { | |
566 | e = ubi->lookuptbl[pool->pebs[i]]; | |
567 | wl_tree_add(e, &ubi->free); | |
568 | ubi->free_count++; | |
569 | } | |
570 | } | |
571 | ||
572 | /** | |
573 | * refill_wl_pool - refills all the fastmap pool used by the | |
574 | * WL sub-system. | |
575 | * @ubi: UBI device description object | |
576 | */ | |
577 | static void refill_wl_pool(struct ubi_device *ubi) | |
578 | { | |
579 | struct ubi_wl_entry *e; | |
580 | struct ubi_fm_pool *pool = &ubi->fm_wl_pool; | |
581 | ||
582 | return_unused_pool_pebs(ubi, pool); | |
583 | ||
584 | for (pool->size = 0; pool->size < pool->max_size; pool->size++) { | |
585 | if (!ubi->free.rb_node || | |
586 | (ubi->free_count - ubi->beb_rsvd_pebs < 5)) | |
587 | break; | |
588 | ||
589 | e = find_wl_entry(ubi, &ubi->free, WL_FREE_MAX_DIFF); | |
590 | self_check_in_wl_tree(ubi, e, &ubi->free); | |
591 | rb_erase(&e->u.rb, &ubi->free); | |
592 | ubi->free_count--; | |
593 | ||
594 | pool->pebs[pool->size] = e->pnum; | |
595 | } | |
596 | pool->used = 0; | |
597 | } | |
598 | ||
599 | /** | |
600 | * refill_wl_user_pool - refills all the fastmap pool used by ubi_wl_get_peb. | |
601 | * @ubi: UBI device description object | |
602 | */ | |
603 | static void refill_wl_user_pool(struct ubi_device *ubi) | |
604 | { | |
605 | struct ubi_fm_pool *pool = &ubi->fm_pool; | |
606 | ||
607 | return_unused_pool_pebs(ubi, pool); | |
608 | ||
609 | for (pool->size = 0; pool->size < pool->max_size; pool->size++) { | |
610 | if (!ubi->free.rb_node || | |
611 | (ubi->free_count - ubi->beb_rsvd_pebs < 1)) | |
612 | break; | |
613 | ||
614 | pool->pebs[pool->size] = __wl_get_peb(ubi); | |
615 | if (pool->pebs[pool->size] < 0) | |
616 | break; | |
617 | } | |
618 | pool->used = 0; | |
619 | } | |
620 | ||
621 | /** | |
622 | * ubi_refill_pools - refills all fastmap PEB pools. | |
623 | * @ubi: UBI device description object | |
624 | */ | |
625 | void ubi_refill_pools(struct ubi_device *ubi) | |
626 | { | |
627 | spin_lock(&ubi->wl_lock); | |
628 | refill_wl_pool(ubi); | |
629 | refill_wl_user_pool(ubi); | |
630 | spin_unlock(&ubi->wl_lock); | |
631 | } | |
632 | ||
633 | /* ubi_wl_get_peb - works exaclty like __wl_get_peb but keeps track of | |
634 | * the fastmap pool. | |
635 | */ | |
636 | int ubi_wl_get_peb(struct ubi_device *ubi) | |
637 | { | |
638 | int ret; | |
639 | struct ubi_fm_pool *pool = &ubi->fm_pool; | |
640 | struct ubi_fm_pool *wl_pool = &ubi->fm_wl_pool; | |
641 | ||
642 | if (!pool->size || !wl_pool->size || pool->used == pool->size || | |
643 | wl_pool->used == wl_pool->size) | |
644 | ubi_update_fastmap(ubi); | |
645 | ||
646 | /* we got not a single free PEB */ | |
647 | if (!pool->size) | |
648 | ret = -ENOSPC; | |
649 | else { | |
650 | spin_lock(&ubi->wl_lock); | |
651 | ret = pool->pebs[pool->used++]; | |
652 | prot_queue_add(ubi, ubi->lookuptbl[ret]); | |
653 | spin_unlock(&ubi->wl_lock); | |
654 | } | |
655 | ||
656 | return ret; | |
657 | } | |
658 | ||
659 | /* get_peb_for_wl - returns a PEB to be used internally by the WL sub-system. | |
660 | * | |
661 | * @ubi: UBI device description object | |
662 | */ | |
663 | static struct ubi_wl_entry *get_peb_for_wl(struct ubi_device *ubi) | |
664 | { | |
665 | struct ubi_fm_pool *pool = &ubi->fm_wl_pool; | |
666 | int pnum; | |
667 | ||
668 | if (pool->used == pool->size || !pool->size) { | |
669 | /* We cannot update the fastmap here because this | |
670 | * function is called in atomic context. | |
671 | * Let's fail here and refill/update it as soon as possible. */ | |
672 | schedule_work(&ubi->fm_work); | |
673 | return NULL; | |
674 | } else { | |
675 | pnum = pool->pebs[pool->used++]; | |
676 | return ubi->lookuptbl[pnum]; | |
677 | } | |
678 | } | |
679 | #else | |
680 | static struct ubi_wl_entry *get_peb_for_wl(struct ubi_device *ubi) | |
681 | { | |
ed4b7021 RW |
682 | struct ubi_wl_entry *e; |
683 | ||
684 | e = find_wl_entry(ubi, &ubi->free, WL_FREE_MAX_DIFF); | |
685 | self_check_in_wl_tree(ubi, e, &ubi->free); | |
686 | rb_erase(&e->u.rb, &ubi->free); | |
687 | ||
688 | return e; | |
8199b901 RW |
689 | } |
690 | ||
691 | int ubi_wl_get_peb(struct ubi_device *ubi) | |
692 | { | |
693 | int peb; | |
694 | ||
695 | spin_lock(&ubi->wl_lock); | |
696 | peb = __wl_get_peb(ubi); | |
697 | spin_unlock(&ubi->wl_lock); | |
698 | ||
699 | return peb; | |
700 | } | |
701 | #endif | |
702 | ||
801c135c | 703 | /** |
7b6c32da | 704 | * prot_queue_del - remove a physical eraseblock from the protection queue. |
801c135c AB |
705 | * @ubi: UBI device description object |
706 | * @pnum: the physical eraseblock to remove | |
43f9b25a | 707 | * |
7b6c32da XX |
708 | * This function deletes PEB @pnum from the protection queue and returns zero |
709 | * in case of success and %-ENODEV if the PEB was not found. | |
801c135c | 710 | */ |
7b6c32da | 711 | static int prot_queue_del(struct ubi_device *ubi, int pnum) |
801c135c | 712 | { |
7b6c32da | 713 | struct ubi_wl_entry *e; |
801c135c | 714 | |
7b6c32da XX |
715 | e = ubi->lookuptbl[pnum]; |
716 | if (!e) | |
717 | return -ENODEV; | |
801c135c | 718 | |
7bf523ae | 719 | if (self_check_in_pq(ubi, e)) |
7b6c32da | 720 | return -ENODEV; |
43f9b25a | 721 | |
7b6c32da XX |
722 | list_del(&e->u.list); |
723 | dbg_wl("deleted PEB %d from the protection queue", e->pnum); | |
43f9b25a | 724 | return 0; |
801c135c AB |
725 | } |
726 | ||
727 | /** | |
728 | * sync_erase - synchronously erase a physical eraseblock. | |
729 | * @ubi: UBI device description object | |
730 | * @e: the the physical eraseblock to erase | |
731 | * @torture: if the physical eraseblock has to be tortured | |
732 | * | |
733 | * This function returns zero in case of success and a negative error code in | |
734 | * case of failure. | |
735 | */ | |
9c9ec147 AB |
736 | static int sync_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, |
737 | int torture) | |
801c135c AB |
738 | { |
739 | int err; | |
740 | struct ubi_ec_hdr *ec_hdr; | |
741 | unsigned long long ec = e->ec; | |
742 | ||
743 | dbg_wl("erase PEB %d, old EC %llu", e->pnum, ec); | |
744 | ||
7bf523ae | 745 | err = self_check_ec(ubi, e->pnum, e->ec); |
adbf05e3 | 746 | if (err) |
801c135c AB |
747 | return -EINVAL; |
748 | ||
33818bbb | 749 | ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_NOFS); |
801c135c AB |
750 | if (!ec_hdr) |
751 | return -ENOMEM; | |
752 | ||
753 | err = ubi_io_sync_erase(ubi, e->pnum, torture); | |
754 | if (err < 0) | |
755 | goto out_free; | |
756 | ||
757 | ec += err; | |
758 | if (ec > UBI_MAX_ERASECOUNTER) { | |
759 | /* | |
760 | * Erase counter overflow. Upgrade UBI and use 64-bit | |
761 | * erase counters internally. | |
762 | */ | |
763 | ubi_err("erase counter overflow at PEB %d, EC %llu", | |
764 | e->pnum, ec); | |
765 | err = -EINVAL; | |
766 | goto out_free; | |
767 | } | |
768 | ||
769 | dbg_wl("erased PEB %d, new EC %llu", e->pnum, ec); | |
770 | ||
3261ebd7 | 771 | ec_hdr->ec = cpu_to_be64(ec); |
801c135c AB |
772 | |
773 | err = ubi_io_write_ec_hdr(ubi, e->pnum, ec_hdr); | |
774 | if (err) | |
775 | goto out_free; | |
776 | ||
777 | e->ec = ec; | |
778 | spin_lock(&ubi->wl_lock); | |
779 | if (e->ec > ubi->max_ec) | |
780 | ubi->max_ec = e->ec; | |
781 | spin_unlock(&ubi->wl_lock); | |
782 | ||
783 | out_free: | |
784 | kfree(ec_hdr); | |
785 | return err; | |
786 | } | |
787 | ||
788 | /** | |
7b6c32da | 789 | * serve_prot_queue - check if it is time to stop protecting PEBs. |
801c135c AB |
790 | * @ubi: UBI device description object |
791 | * | |
7b6c32da XX |
792 | * This function is called after each erase operation and removes PEBs from the |
793 | * tail of the protection queue. These PEBs have been protected for long enough | |
794 | * and should be moved to the used tree. | |
801c135c | 795 | */ |
7b6c32da | 796 | static void serve_prot_queue(struct ubi_device *ubi) |
801c135c | 797 | { |
7b6c32da XX |
798 | struct ubi_wl_entry *e, *tmp; |
799 | int count; | |
801c135c AB |
800 | |
801 | /* | |
802 | * There may be several protected physical eraseblock to remove, | |
803 | * process them all. | |
804 | */ | |
7b6c32da XX |
805 | repeat: |
806 | count = 0; | |
807 | spin_lock(&ubi->wl_lock); | |
808 | list_for_each_entry_safe(e, tmp, &ubi->pq[ubi->pq_head], u.list) { | |
809 | dbg_wl("PEB %d EC %d protection over, move to used tree", | |
810 | e->pnum, e->ec); | |
801c135c | 811 | |
7b6c32da XX |
812 | list_del(&e->u.list); |
813 | wl_tree_add(e, &ubi->used); | |
814 | if (count++ > 32) { | |
815 | /* | |
816 | * Let's be nice and avoid holding the spinlock for | |
817 | * too long. | |
818 | */ | |
801c135c | 819 | spin_unlock(&ubi->wl_lock); |
7b6c32da XX |
820 | cond_resched(); |
821 | goto repeat; | |
801c135c | 822 | } |
801c135c | 823 | } |
7b6c32da XX |
824 | |
825 | ubi->pq_head += 1; | |
826 | if (ubi->pq_head == UBI_PROT_QUEUE_LEN) | |
827 | ubi->pq_head = 0; | |
828 | ubi_assert(ubi->pq_head >= 0 && ubi->pq_head < UBI_PROT_QUEUE_LEN); | |
829 | spin_unlock(&ubi->wl_lock); | |
801c135c AB |
830 | } |
831 | ||
832 | /** | |
8199b901 | 833 | * __schedule_ubi_work - schedule a work. |
801c135c AB |
834 | * @ubi: UBI device description object |
835 | * @wrk: the work to schedule | |
836 | * | |
7b6c32da | 837 | * This function adds a work defined by @wrk to the tail of the pending works |
8199b901 | 838 | * list. Can only be used of ubi->work_sem is already held in read mode! |
801c135c | 839 | */ |
8199b901 | 840 | static void __schedule_ubi_work(struct ubi_device *ubi, struct ubi_work *wrk) |
801c135c AB |
841 | { |
842 | spin_lock(&ubi->wl_lock); | |
843 | list_add_tail(&wrk->list, &ubi->works); | |
844 | ubi_assert(ubi->works_count >= 0); | |
845 | ubi->works_count += 1; | |
27a0f2a3 | 846 | if (ubi->thread_enabled && !ubi_dbg_is_bgt_disabled(ubi)) |
801c135c AB |
847 | wake_up_process(ubi->bgt_thread); |
848 | spin_unlock(&ubi->wl_lock); | |
849 | } | |
850 | ||
8199b901 RW |
851 | /** |
852 | * schedule_ubi_work - schedule a work. | |
853 | * @ubi: UBI device description object | |
854 | * @wrk: the work to schedule | |
855 | * | |
856 | * This function adds a work defined by @wrk to the tail of the pending works | |
857 | * list. | |
858 | */ | |
859 | static void schedule_ubi_work(struct ubi_device *ubi, struct ubi_work *wrk) | |
860 | { | |
861 | down_read(&ubi->work_sem); | |
862 | __schedule_ubi_work(ubi, wrk); | |
863 | up_read(&ubi->work_sem); | |
864 | } | |
865 | ||
801c135c AB |
866 | static int erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk, |
867 | int cancel); | |
868 | ||
8199b901 RW |
869 | #ifdef CONFIG_MTD_UBI_FASTMAP |
870 | /** | |
871 | * ubi_is_erase_work - checks whether a work is erase work. | |
872 | * @wrk: The work object to be checked | |
873 | */ | |
874 | int ubi_is_erase_work(struct ubi_work *wrk) | |
875 | { | |
876 | return wrk->func == erase_worker; | |
877 | } | |
878 | #endif | |
879 | ||
801c135c AB |
880 | /** |
881 | * schedule_erase - schedule an erase work. | |
882 | * @ubi: UBI device description object | |
883 | * @e: the WL entry of the physical eraseblock to erase | |
d36e59e6 JR |
884 | * @vol_id: the volume ID that last used this PEB |
885 | * @lnum: the last used logical eraseblock number for the PEB | |
801c135c AB |
886 | * @torture: if the physical eraseblock has to be tortured |
887 | * | |
888 | * This function returns zero in case of success and a %-ENOMEM in case of | |
889 | * failure. | |
890 | */ | |
891 | static int schedule_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, | |
d36e59e6 | 892 | int vol_id, int lnum, int torture) |
801c135c AB |
893 | { |
894 | struct ubi_work *wl_wrk; | |
895 | ||
8199b901 RW |
896 | ubi_assert(e); |
897 | ubi_assert(!ubi_is_fm_block(ubi, e->pnum)); | |
898 | ||
801c135c AB |
899 | dbg_wl("schedule erasure of PEB %d, EC %d, torture %d", |
900 | e->pnum, e->ec, torture); | |
901 | ||
33818bbb | 902 | wl_wrk = kmalloc(sizeof(struct ubi_work), GFP_NOFS); |
801c135c AB |
903 | if (!wl_wrk) |
904 | return -ENOMEM; | |
905 | ||
906 | wl_wrk->func = &erase_worker; | |
907 | wl_wrk->e = e; | |
d36e59e6 JR |
908 | wl_wrk->vol_id = vol_id; |
909 | wl_wrk->lnum = lnum; | |
801c135c AB |
910 | wl_wrk->torture = torture; |
911 | ||
912 | schedule_ubi_work(ubi, wl_wrk); | |
913 | return 0; | |
914 | } | |
915 | ||
8199b901 RW |
916 | /** |
917 | * do_sync_erase - run the erase worker synchronously. | |
918 | * @ubi: UBI device description object | |
919 | * @e: the WL entry of the physical eraseblock to erase | |
920 | * @vol_id: the volume ID that last used this PEB | |
921 | * @lnum: the last used logical eraseblock number for the PEB | |
922 | * @torture: if the physical eraseblock has to be tortured | |
923 | * | |
924 | */ | |
925 | static int do_sync_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, | |
926 | int vol_id, int lnum, int torture) | |
927 | { | |
928 | struct ubi_work *wl_wrk; | |
929 | ||
930 | dbg_wl("sync erase of PEB %i", e->pnum); | |
931 | ||
932 | wl_wrk = kmalloc(sizeof(struct ubi_work), GFP_NOFS); | |
933 | if (!wl_wrk) | |
934 | return -ENOMEM; | |
935 | ||
936 | wl_wrk->e = e; | |
937 | wl_wrk->vol_id = vol_id; | |
938 | wl_wrk->lnum = lnum; | |
939 | wl_wrk->torture = torture; | |
940 | ||
941 | return erase_worker(ubi, wl_wrk, 0); | |
942 | } | |
943 | ||
944 | #ifdef CONFIG_MTD_UBI_FASTMAP | |
945 | /** | |
946 | * ubi_wl_put_fm_peb - returns a PEB used in a fastmap to the wear-leveling | |
947 | * sub-system. | |
948 | * see: ubi_wl_put_peb() | |
949 | * | |
950 | * @ubi: UBI device description object | |
951 | * @fm_e: physical eraseblock to return | |
952 | * @lnum: the last used logical eraseblock number for the PEB | |
953 | * @torture: if this physical eraseblock has to be tortured | |
954 | */ | |
955 | int ubi_wl_put_fm_peb(struct ubi_device *ubi, struct ubi_wl_entry *fm_e, | |
956 | int lnum, int torture) | |
957 | { | |
958 | struct ubi_wl_entry *e; | |
959 | int vol_id, pnum = fm_e->pnum; | |
960 | ||
961 | dbg_wl("PEB %d", pnum); | |
962 | ||
963 | ubi_assert(pnum >= 0); | |
964 | ubi_assert(pnum < ubi->peb_count); | |
965 | ||
966 | spin_lock(&ubi->wl_lock); | |
967 | e = ubi->lookuptbl[pnum]; | |
968 | ||
969 | /* This can happen if we recovered from a fastmap the very | |
970 | * first time and writing now a new one. In this case the wl system | |
971 | * has never seen any PEB used by the original fastmap. | |
972 | */ | |
973 | if (!e) { | |
974 | e = fm_e; | |
975 | ubi_assert(e->ec >= 0); | |
976 | ubi->lookuptbl[pnum] = e; | |
977 | } else { | |
978 | e->ec = fm_e->ec; | |
979 | kfree(fm_e); | |
980 | } | |
981 | ||
982 | spin_unlock(&ubi->wl_lock); | |
983 | ||
984 | vol_id = lnum ? UBI_FM_DATA_VOLUME_ID : UBI_FM_SB_VOLUME_ID; | |
985 | return schedule_erase(ubi, e, vol_id, lnum, torture); | |
986 | } | |
987 | #endif | |
988 | ||
801c135c AB |
989 | /** |
990 | * wear_leveling_worker - wear-leveling worker function. | |
991 | * @ubi: UBI device description object | |
992 | * @wrk: the work object | |
993 | * @cancel: non-zero if the worker has to free memory and exit | |
994 | * | |
995 | * This function copies a more worn out physical eraseblock to a less worn out | |
996 | * one. Returns zero in case of success and a negative error code in case of | |
997 | * failure. | |
998 | */ | |
999 | static int wear_leveling_worker(struct ubi_device *ubi, struct ubi_work *wrk, | |
1000 | int cancel) | |
1001 | { | |
b86a2c56 | 1002 | int err, scrubbing = 0, torture = 0, protect = 0, erroneous = 0; |
9c259a52 | 1003 | int vol_id = -1, uninitialized_var(lnum); |
8199b901 RW |
1004 | #ifdef CONFIG_MTD_UBI_FASTMAP |
1005 | int anchor = wrk->anchor; | |
1006 | #endif | |
801c135c AB |
1007 | struct ubi_wl_entry *e1, *e2; |
1008 | struct ubi_vid_hdr *vid_hdr; | |
1009 | ||
1010 | kfree(wrk); | |
801c135c AB |
1011 | if (cancel) |
1012 | return 0; | |
1013 | ||
33818bbb | 1014 | vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS); |
801c135c AB |
1015 | if (!vid_hdr) |
1016 | return -ENOMEM; | |
1017 | ||
43f9b25a | 1018 | mutex_lock(&ubi->move_mutex); |
801c135c | 1019 | spin_lock(&ubi->wl_lock); |
43f9b25a AB |
1020 | ubi_assert(!ubi->move_from && !ubi->move_to); |
1021 | ubi_assert(!ubi->move_to_put); | |
801c135c | 1022 | |
43f9b25a | 1023 | if (!ubi->free.rb_node || |
5abde384 | 1024 | (!ubi->used.rb_node && !ubi->scrub.rb_node)) { |
801c135c | 1025 | /* |
43f9b25a AB |
1026 | * No free physical eraseblocks? Well, they must be waiting in |
1027 | * the queue to be erased. Cancel movement - it will be | |
1028 | * triggered again when a free physical eraseblock appears. | |
801c135c AB |
1029 | * |
1030 | * No used physical eraseblocks? They must be temporarily | |
1031 | * protected from being moved. They will be moved to the | |
1032 | * @ubi->used tree later and the wear-leveling will be | |
1033 | * triggered again. | |
1034 | */ | |
1035 | dbg_wl("cancel WL, a list is empty: free %d, used %d", | |
5abde384 | 1036 | !ubi->free.rb_node, !ubi->used.rb_node); |
43f9b25a | 1037 | goto out_cancel; |
801c135c AB |
1038 | } |
1039 | ||
8199b901 RW |
1040 | #ifdef CONFIG_MTD_UBI_FASTMAP |
1041 | /* Check whether we need to produce an anchor PEB */ | |
1042 | if (!anchor) | |
1043 | anchor = !anchor_pebs_avalible(&ubi->free); | |
1044 | ||
1045 | if (anchor) { | |
1046 | e1 = find_anchor_wl_entry(&ubi->used); | |
1047 | if (!e1) | |
1048 | goto out_cancel; | |
1049 | e2 = get_peb_for_wl(ubi); | |
1050 | if (!e2) | |
1051 | goto out_cancel; | |
1052 | ||
1053 | self_check_in_wl_tree(ubi, e1, &ubi->used); | |
1054 | rb_erase(&e1->u.rb, &ubi->used); | |
1055 | dbg_wl("anchor-move PEB %d to PEB %d", e1->pnum, e2->pnum); | |
1056 | } else if (!ubi->scrub.rb_node) { | |
1057 | #else | |
5abde384 | 1058 | if (!ubi->scrub.rb_node) { |
8199b901 | 1059 | #endif |
801c135c AB |
1060 | /* |
1061 | * Now pick the least worn-out used physical eraseblock and a | |
1062 | * highly worn-out free physical eraseblock. If the erase | |
1063 | * counters differ much enough, start wear-leveling. | |
1064 | */ | |
23553b2c | 1065 | e1 = rb_entry(rb_first(&ubi->used), struct ubi_wl_entry, u.rb); |
8199b901 RW |
1066 | e2 = get_peb_for_wl(ubi); |
1067 | if (!e2) | |
1068 | goto out_cancel; | |
801c135c AB |
1069 | |
1070 | if (!(e2->ec - e1->ec >= UBI_WL_THRESHOLD)) { | |
1071 | dbg_wl("no WL needed: min used EC %d, max free EC %d", | |
1072 | e1->ec, e2->ec); | |
43f9b25a | 1073 | goto out_cancel; |
801c135c | 1074 | } |
7bf523ae | 1075 | self_check_in_wl_tree(ubi, e1, &ubi->used); |
23553b2c | 1076 | rb_erase(&e1->u.rb, &ubi->used); |
801c135c AB |
1077 | dbg_wl("move PEB %d EC %d to PEB %d EC %d", |
1078 | e1->pnum, e1->ec, e2->pnum, e2->ec); | |
1079 | } else { | |
43f9b25a AB |
1080 | /* Perform scrubbing */ |
1081 | scrubbing = 1; | |
23553b2c | 1082 | e1 = rb_entry(rb_first(&ubi->scrub), struct ubi_wl_entry, u.rb); |
8199b901 RW |
1083 | e2 = get_peb_for_wl(ubi); |
1084 | if (!e2) | |
1085 | goto out_cancel; | |
1086 | ||
7bf523ae | 1087 | self_check_in_wl_tree(ubi, e1, &ubi->scrub); |
23553b2c | 1088 | rb_erase(&e1->u.rb, &ubi->scrub); |
801c135c AB |
1089 | dbg_wl("scrub PEB %d to PEB %d", e1->pnum, e2->pnum); |
1090 | } | |
1091 | ||
801c135c AB |
1092 | ubi->move_from = e1; |
1093 | ubi->move_to = e2; | |
1094 | spin_unlock(&ubi->wl_lock); | |
1095 | ||
1096 | /* | |
1097 | * Now we are going to copy physical eraseblock @e1->pnum to @e2->pnum. | |
1098 | * We so far do not know which logical eraseblock our physical | |
1099 | * eraseblock (@e1) belongs to. We have to read the volume identifier | |
1100 | * header first. | |
43f9b25a AB |
1101 | * |
1102 | * Note, we are protected from this PEB being unmapped and erased. The | |
1103 | * 'ubi_wl_put_peb()' would wait for moving to be finished if the PEB | |
1104 | * which is being moved was unmapped. | |
801c135c AB |
1105 | */ |
1106 | ||
1107 | err = ubi_io_read_vid_hdr(ubi, e1->pnum, vid_hdr, 0); | |
1108 | if (err && err != UBI_IO_BITFLIPS) { | |
74d82d26 | 1109 | if (err == UBI_IO_FF) { |
801c135c AB |
1110 | /* |
1111 | * We are trying to move PEB without a VID header. UBI | |
1112 | * always write VID headers shortly after the PEB was | |
87960c0b AB |
1113 | * given, so we have a situation when it has not yet |
1114 | * had a chance to write it, because it was preempted. | |
1115 | * So add this PEB to the protection queue so far, | |
815bc5f8 AB |
1116 | * because presumably more data will be written there |
1117 | * (including the missing VID header), and then we'll | |
87960c0b | 1118 | * move it. |
801c135c AB |
1119 | */ |
1120 | dbg_wl("PEB %d has no VID header", e1->pnum); | |
87960c0b | 1121 | protect = 1; |
43f9b25a | 1122 | goto out_not_moved; |
92e1a7d9 AB |
1123 | } else if (err == UBI_IO_FF_BITFLIPS) { |
1124 | /* | |
1125 | * The same situation as %UBI_IO_FF, but bit-flips were | |
1126 | * detected. It is better to schedule this PEB for | |
1127 | * scrubbing. | |
1128 | */ | |
1129 | dbg_wl("PEB %d has no VID header but has bit-flips", | |
1130 | e1->pnum); | |
1131 | scrubbing = 1; | |
1132 | goto out_not_moved; | |
801c135c | 1133 | } |
43f9b25a AB |
1134 | |
1135 | ubi_err("error %d while reading VID header from PEB %d", | |
1136 | err, e1->pnum); | |
43f9b25a | 1137 | goto out_error; |
801c135c AB |
1138 | } |
1139 | ||
9c259a52 AB |
1140 | vol_id = be32_to_cpu(vid_hdr->vol_id); |
1141 | lnum = be32_to_cpu(vid_hdr->lnum); | |
1142 | ||
801c135c AB |
1143 | err = ubi_eba_copy_leb(ubi, e1->pnum, e2->pnum, vid_hdr); |
1144 | if (err) { | |
87960c0b AB |
1145 | if (err == MOVE_CANCEL_RACE) { |
1146 | /* | |
1147 | * The LEB has not been moved because the volume is | |
1148 | * being deleted or the PEB has been put meanwhile. We | |
1149 | * should prevent this PEB from being selected for | |
1150 | * wear-leveling movement again, so put it to the | |
1151 | * protection queue. | |
1152 | */ | |
1153 | protect = 1; | |
1154 | goto out_not_moved; | |
1155 | } | |
e801e128 BP |
1156 | if (err == MOVE_RETRY) { |
1157 | scrubbing = 1; | |
1158 | goto out_not_moved; | |
1159 | } | |
cc831464 | 1160 | if (err == MOVE_TARGET_BITFLIPS || err == MOVE_TARGET_WR_ERR || |
b86a2c56 | 1161 | err == MOVE_TARGET_RD_ERR) { |
9c259a52 AB |
1162 | /* |
1163 | * Target PEB had bit-flips or write error - torture it. | |
1164 | */ | |
6fa6f5bb | 1165 | torture = 1; |
43f9b25a | 1166 | goto out_not_moved; |
6fa6f5bb | 1167 | } |
87960c0b | 1168 | |
b86a2c56 AB |
1169 | if (err == MOVE_SOURCE_RD_ERR) { |
1170 | /* | |
1171 | * An error happened while reading the source PEB. Do | |
1172 | * not switch to R/O mode in this case, and give the | |
1173 | * upper layers a possibility to recover from this, | |
1174 | * e.g. by unmapping corresponding LEB. Instead, just | |
815bc5f8 AB |
1175 | * put this PEB to the @ubi->erroneous list to prevent |
1176 | * UBI from trying to move it over and over again. | |
b86a2c56 AB |
1177 | */ |
1178 | if (ubi->erroneous_peb_count > ubi->max_erroneous) { | |
1179 | ubi_err("too many erroneous eraseblocks (%d)", | |
1180 | ubi->erroneous_peb_count); | |
1181 | goto out_error; | |
1182 | } | |
1183 | erroneous = 1; | |
1184 | goto out_not_moved; | |
1185 | } | |
1186 | ||
90bf0265 AB |
1187 | if (err < 0) |
1188 | goto out_error; | |
43f9b25a | 1189 | |
87960c0b | 1190 | ubi_assert(0); |
801c135c AB |
1191 | } |
1192 | ||
6a8f483f | 1193 | /* The PEB has been successfully moved */ |
6a8f483f | 1194 | if (scrubbing) |
9c259a52 AB |
1195 | ubi_msg("scrubbed PEB %d (LEB %d:%d), data moved to PEB %d", |
1196 | e1->pnum, vol_id, lnum, e2->pnum); | |
1197 | ubi_free_vid_hdr(ubi, vid_hdr); | |
8c1e6ee1 | 1198 | |
801c135c | 1199 | spin_lock(&ubi->wl_lock); |
3c98b0a0 | 1200 | if (!ubi->move_to_put) { |
5abde384 | 1201 | wl_tree_add(e2, &ubi->used); |
3c98b0a0 AB |
1202 | e2 = NULL; |
1203 | } | |
801c135c | 1204 | ubi->move_from = ubi->move_to = NULL; |
43f9b25a | 1205 | ubi->move_to_put = ubi->wl_scheduled = 0; |
801c135c AB |
1206 | spin_unlock(&ubi->wl_lock); |
1207 | ||
8199b901 | 1208 | err = do_sync_erase(ubi, e1, vol_id, lnum, 0); |
3c98b0a0 | 1209 | if (err) { |
87960c0b | 1210 | kmem_cache_free(ubi_wl_entry_slab, e1); |
21d08bbc AB |
1211 | if (e2) |
1212 | kmem_cache_free(ubi_wl_entry_slab, e2); | |
87960c0b | 1213 | goto out_ro; |
3c98b0a0 | 1214 | } |
6a8f483f | 1215 | |
3c98b0a0 | 1216 | if (e2) { |
801c135c AB |
1217 | /* |
1218 | * Well, the target PEB was put meanwhile, schedule it for | |
1219 | * erasure. | |
1220 | */ | |
9c259a52 AB |
1221 | dbg_wl("PEB %d (LEB %d:%d) was put meanwhile, erase", |
1222 | e2->pnum, vol_id, lnum); | |
8199b901 | 1223 | err = do_sync_erase(ubi, e2, vol_id, lnum, 0); |
87960c0b AB |
1224 | if (err) { |
1225 | kmem_cache_free(ubi_wl_entry_slab, e2); | |
1226 | goto out_ro; | |
1227 | } | |
801c135c AB |
1228 | } |
1229 | ||
801c135c | 1230 | dbg_wl("done"); |
43f9b25a AB |
1231 | mutex_unlock(&ubi->move_mutex); |
1232 | return 0; | |
801c135c AB |
1233 | |
1234 | /* | |
43f9b25a AB |
1235 | * For some reasons the LEB was not moved, might be an error, might be |
1236 | * something else. @e1 was not changed, so return it back. @e2 might | |
6fa6f5bb | 1237 | * have been changed, schedule it for erasure. |
801c135c | 1238 | */ |
43f9b25a | 1239 | out_not_moved: |
9c259a52 AB |
1240 | if (vol_id != -1) |
1241 | dbg_wl("cancel moving PEB %d (LEB %d:%d) to PEB %d (%d)", | |
1242 | e1->pnum, vol_id, lnum, e2->pnum, err); | |
1243 | else | |
1244 | dbg_wl("cancel moving PEB %d to PEB %d (%d)", | |
1245 | e1->pnum, e2->pnum, err); | |
801c135c | 1246 | spin_lock(&ubi->wl_lock); |
87960c0b AB |
1247 | if (protect) |
1248 | prot_queue_add(ubi, e1); | |
b86a2c56 AB |
1249 | else if (erroneous) { |
1250 | wl_tree_add(e1, &ubi->erroneous); | |
1251 | ubi->erroneous_peb_count += 1; | |
1252 | } else if (scrubbing) | |
43f9b25a | 1253 | wl_tree_add(e1, &ubi->scrub); |
801c135c | 1254 | else |
5abde384 | 1255 | wl_tree_add(e1, &ubi->used); |
6fa6f5bb | 1256 | ubi_assert(!ubi->move_to_put); |
801c135c | 1257 | ubi->move_from = ubi->move_to = NULL; |
6fa6f5bb | 1258 | ubi->wl_scheduled = 0; |
801c135c AB |
1259 | spin_unlock(&ubi->wl_lock); |
1260 | ||
87960c0b | 1261 | ubi_free_vid_hdr(ubi, vid_hdr); |
8199b901 | 1262 | err = do_sync_erase(ubi, e2, vol_id, lnum, torture); |
87960c0b AB |
1263 | if (err) { |
1264 | kmem_cache_free(ubi_wl_entry_slab, e2); | |
1265 | goto out_ro; | |
1266 | } | |
43f9b25a AB |
1267 | mutex_unlock(&ubi->move_mutex); |
1268 | return 0; | |
1269 | ||
1270 | out_error: | |
9c259a52 AB |
1271 | if (vol_id != -1) |
1272 | ubi_err("error %d while moving PEB %d to PEB %d", | |
1273 | err, e1->pnum, e2->pnum); | |
1274 | else | |
1275 | ubi_err("error %d while moving PEB %d (LEB %d:%d) to PEB %d", | |
1276 | err, e1->pnum, vol_id, lnum, e2->pnum); | |
43f9b25a AB |
1277 | spin_lock(&ubi->wl_lock); |
1278 | ubi->move_from = ubi->move_to = NULL; | |
1279 | ubi->move_to_put = ubi->wl_scheduled = 0; | |
1280 | spin_unlock(&ubi->wl_lock); | |
1281 | ||
87960c0b AB |
1282 | ubi_free_vid_hdr(ubi, vid_hdr); |
1283 | kmem_cache_free(ubi_wl_entry_slab, e1); | |
1284 | kmem_cache_free(ubi_wl_entry_slab, e2); | |
43f9b25a | 1285 | |
87960c0b AB |
1286 | out_ro: |
1287 | ubi_ro_mode(ubi); | |
43f9b25a | 1288 | mutex_unlock(&ubi->move_mutex); |
87960c0b AB |
1289 | ubi_assert(err != 0); |
1290 | return err < 0 ? err : -EIO; | |
43f9b25a AB |
1291 | |
1292 | out_cancel: | |
1293 | ubi->wl_scheduled = 0; | |
1294 | spin_unlock(&ubi->wl_lock); | |
1295 | mutex_unlock(&ubi->move_mutex); | |
1296 | ubi_free_vid_hdr(ubi, vid_hdr); | |
1297 | return 0; | |
801c135c AB |
1298 | } |
1299 | ||
1300 | /** | |
1301 | * ensure_wear_leveling - schedule wear-leveling if it is needed. | |
1302 | * @ubi: UBI device description object | |
8199b901 | 1303 | * @nested: set to non-zero if this function is called from UBI worker |
801c135c AB |
1304 | * |
1305 | * This function checks if it is time to start wear-leveling and schedules it | |
1306 | * if yes. This function returns zero in case of success and a negative error | |
1307 | * code in case of failure. | |
1308 | */ | |
8199b901 | 1309 | static int ensure_wear_leveling(struct ubi_device *ubi, int nested) |
801c135c AB |
1310 | { |
1311 | int err = 0; | |
1312 | struct ubi_wl_entry *e1; | |
1313 | struct ubi_wl_entry *e2; | |
1314 | struct ubi_work *wrk; | |
1315 | ||
1316 | spin_lock(&ubi->wl_lock); | |
1317 | if (ubi->wl_scheduled) | |
1318 | /* Wear-leveling is already in the work queue */ | |
1319 | goto out_unlock; | |
1320 | ||
1321 | /* | |
1322 | * If the ubi->scrub tree is not empty, scrubbing is needed, and the | |
1323 | * the WL worker has to be scheduled anyway. | |
1324 | */ | |
5abde384 AB |
1325 | if (!ubi->scrub.rb_node) { |
1326 | if (!ubi->used.rb_node || !ubi->free.rb_node) | |
801c135c AB |
1327 | /* No physical eraseblocks - no deal */ |
1328 | goto out_unlock; | |
1329 | ||
1330 | /* | |
1331 | * We schedule wear-leveling only if the difference between the | |
1332 | * lowest erase counter of used physical eraseblocks and a high | |
025dfdaf | 1333 | * erase counter of free physical eraseblocks is greater than |
801c135c AB |
1334 | * %UBI_WL_THRESHOLD. |
1335 | */ | |
23553b2c | 1336 | e1 = rb_entry(rb_first(&ubi->used), struct ubi_wl_entry, u.rb); |
8199b901 | 1337 | e2 = find_wl_entry(ubi, &ubi->free, WL_FREE_MAX_DIFF); |
801c135c AB |
1338 | |
1339 | if (!(e2->ec - e1->ec >= UBI_WL_THRESHOLD)) | |
1340 | goto out_unlock; | |
1341 | dbg_wl("schedule wear-leveling"); | |
1342 | } else | |
1343 | dbg_wl("schedule scrubbing"); | |
1344 | ||
1345 | ubi->wl_scheduled = 1; | |
1346 | spin_unlock(&ubi->wl_lock); | |
1347 | ||
33818bbb | 1348 | wrk = kmalloc(sizeof(struct ubi_work), GFP_NOFS); |
801c135c AB |
1349 | if (!wrk) { |
1350 | err = -ENOMEM; | |
1351 | goto out_cancel; | |
1352 | } | |
1353 | ||
8199b901 | 1354 | wrk->anchor = 0; |
801c135c | 1355 | wrk->func = &wear_leveling_worker; |
8199b901 RW |
1356 | if (nested) |
1357 | __schedule_ubi_work(ubi, wrk); | |
1358 | else | |
1359 | schedule_ubi_work(ubi, wrk); | |
801c135c AB |
1360 | return err; |
1361 | ||
1362 | out_cancel: | |
1363 | spin_lock(&ubi->wl_lock); | |
1364 | ubi->wl_scheduled = 0; | |
1365 | out_unlock: | |
1366 | spin_unlock(&ubi->wl_lock); | |
1367 | return err; | |
1368 | } | |
1369 | ||
8199b901 RW |
1370 | #ifdef CONFIG_MTD_UBI_FASTMAP |
1371 | /** | |
1372 | * ubi_ensure_anchor_pebs - schedule wear-leveling to produce an anchor PEB. | |
1373 | * @ubi: UBI device description object | |
1374 | */ | |
1375 | int ubi_ensure_anchor_pebs(struct ubi_device *ubi) | |
1376 | { | |
1377 | struct ubi_work *wrk; | |
1378 | ||
1379 | spin_lock(&ubi->wl_lock); | |
1380 | if (ubi->wl_scheduled) { | |
1381 | spin_unlock(&ubi->wl_lock); | |
1382 | return 0; | |
1383 | } | |
1384 | ubi->wl_scheduled = 1; | |
1385 | spin_unlock(&ubi->wl_lock); | |
1386 | ||
1387 | wrk = kmalloc(sizeof(struct ubi_work), GFP_NOFS); | |
1388 | if (!wrk) { | |
1389 | spin_lock(&ubi->wl_lock); | |
1390 | ubi->wl_scheduled = 0; | |
1391 | spin_unlock(&ubi->wl_lock); | |
1392 | return -ENOMEM; | |
1393 | } | |
1394 | ||
1395 | wrk->anchor = 1; | |
1396 | wrk->func = &wear_leveling_worker; | |
1397 | schedule_ubi_work(ubi, wrk); | |
1398 | return 0; | |
1399 | } | |
1400 | #endif | |
1401 | ||
801c135c AB |
1402 | /** |
1403 | * erase_worker - physical eraseblock erase worker function. | |
1404 | * @ubi: UBI device description object | |
1405 | * @wl_wrk: the work object | |
1406 | * @cancel: non-zero if the worker has to free memory and exit | |
1407 | * | |
1408 | * This function erases a physical eraseblock and perform torture testing if | |
1409 | * needed. It also takes care about marking the physical eraseblock bad if | |
1410 | * needed. Returns zero in case of success and a negative error code in case of | |
1411 | * failure. | |
1412 | */ | |
1413 | static int erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk, | |
1414 | int cancel) | |
1415 | { | |
801c135c | 1416 | struct ubi_wl_entry *e = wl_wrk->e; |
37f758a0 | 1417 | int pnum = e->pnum; |
d36e59e6 JR |
1418 | int vol_id = wl_wrk->vol_id; |
1419 | int lnum = wl_wrk->lnum; | |
37f758a0 | 1420 | int err, available_consumed = 0; |
801c135c AB |
1421 | |
1422 | if (cancel) { | |
1423 | dbg_wl("cancel erasure of PEB %d EC %d", pnum, e->ec); | |
1424 | kfree(wl_wrk); | |
06b68ba1 | 1425 | kmem_cache_free(ubi_wl_entry_slab, e); |
801c135c AB |
1426 | return 0; |
1427 | } | |
1428 | ||
d36e59e6 JR |
1429 | dbg_wl("erase PEB %d EC %d LEB %d:%d", |
1430 | pnum, e->ec, wl_wrk->vol_id, wl_wrk->lnum); | |
801c135c | 1431 | |
8199b901 RW |
1432 | ubi_assert(!ubi_is_fm_block(ubi, e->pnum)); |
1433 | ||
801c135c AB |
1434 | err = sync_erase(ubi, e, wl_wrk->torture); |
1435 | if (!err) { | |
1436 | /* Fine, we've erased it successfully */ | |
1437 | kfree(wl_wrk); | |
1438 | ||
1439 | spin_lock(&ubi->wl_lock); | |
5abde384 | 1440 | wl_tree_add(e, &ubi->free); |
8199b901 | 1441 | ubi->free_count++; |
801c135c AB |
1442 | spin_unlock(&ubi->wl_lock); |
1443 | ||
1444 | /* | |
9c9ec147 AB |
1445 | * One more erase operation has happened, take care about |
1446 | * protected physical eraseblocks. | |
801c135c | 1447 | */ |
7b6c32da | 1448 | serve_prot_queue(ubi); |
801c135c AB |
1449 | |
1450 | /* And take care about wear-leveling */ | |
8199b901 | 1451 | err = ensure_wear_leveling(ubi, 1); |
801c135c AB |
1452 | return err; |
1453 | } | |
1454 | ||
8d2d4011 | 1455 | ubi_err("failed to erase PEB %d, error %d", pnum, err); |
801c135c | 1456 | kfree(wl_wrk); |
801c135c | 1457 | |
784c1454 AB |
1458 | if (err == -EINTR || err == -ENOMEM || err == -EAGAIN || |
1459 | err == -EBUSY) { | |
1460 | int err1; | |
1461 | ||
1462 | /* Re-schedule the LEB for erasure */ | |
d36e59e6 | 1463 | err1 = schedule_erase(ubi, e, vol_id, lnum, 0); |
784c1454 AB |
1464 | if (err1) { |
1465 | err = err1; | |
1466 | goto out_ro; | |
1467 | } | |
1468 | return err; | |
e57e0d8e AB |
1469 | } |
1470 | ||
1471 | kmem_cache_free(ubi_wl_entry_slab, e); | |
1472 | if (err != -EIO) | |
801c135c AB |
1473 | /* |
1474 | * If this is not %-EIO, we have no idea what to do. Scheduling | |
1475 | * this physical eraseblock for erasure again would cause | |
815bc5f8 | 1476 | * errors again and again. Well, lets switch to R/O mode. |
801c135c | 1477 | */ |
784c1454 | 1478 | goto out_ro; |
801c135c AB |
1479 | |
1480 | /* It is %-EIO, the PEB went bad */ | |
1481 | ||
1482 | if (!ubi->bad_allowed) { | |
1483 | ubi_err("bad physical eraseblock %d detected", pnum); | |
784c1454 AB |
1484 | goto out_ro; |
1485 | } | |
801c135c | 1486 | |
784c1454 | 1487 | spin_lock(&ubi->volumes_lock); |
784c1454 | 1488 | if (ubi->beb_rsvd_pebs == 0) { |
37f758a0 SL |
1489 | if (ubi->avail_pebs == 0) { |
1490 | spin_unlock(&ubi->volumes_lock); | |
1491 | ubi_err("no reserved/available physical eraseblocks"); | |
1492 | goto out_ro; | |
1493 | } | |
1494 | ubi->avail_pebs -= 1; | |
1495 | available_consumed = 1; | |
784c1454 | 1496 | } |
784c1454 | 1497 | spin_unlock(&ubi->volumes_lock); |
801c135c | 1498 | |
52b605d1 | 1499 | ubi_msg("mark PEB %d as bad", pnum); |
784c1454 AB |
1500 | err = ubi_io_mark_bad(ubi, pnum); |
1501 | if (err) | |
1502 | goto out_ro; | |
1503 | ||
1504 | spin_lock(&ubi->volumes_lock); | |
37f758a0 SL |
1505 | if (ubi->beb_rsvd_pebs > 0) { |
1506 | if (available_consumed) { | |
1507 | /* | |
1508 | * The amount of reserved PEBs increased since we last | |
1509 | * checked. | |
1510 | */ | |
1511 | ubi->avail_pebs += 1; | |
1512 | available_consumed = 0; | |
1513 | } | |
1514 | ubi->beb_rsvd_pebs -= 1; | |
1515 | } | |
784c1454 AB |
1516 | ubi->bad_peb_count += 1; |
1517 | ubi->good_peb_count -= 1; | |
1518 | ubi_calculate_reserved(ubi); | |
37f758a0 SL |
1519 | if (available_consumed) |
1520 | ubi_warn("no PEBs in the reserved pool, used an available PEB"); | |
1521 | else if (ubi->beb_rsvd_pebs) | |
52b605d1 AB |
1522 | ubi_msg("%d PEBs left in the reserve", ubi->beb_rsvd_pebs); |
1523 | else | |
37f758a0 | 1524 | ubi_warn("last PEB from the reserve was used"); |
784c1454 AB |
1525 | spin_unlock(&ubi->volumes_lock); |
1526 | ||
1527 | return err; | |
801c135c | 1528 | |
784c1454 | 1529 | out_ro: |
37f758a0 SL |
1530 | if (available_consumed) { |
1531 | spin_lock(&ubi->volumes_lock); | |
1532 | ubi->avail_pebs += 1; | |
1533 | spin_unlock(&ubi->volumes_lock); | |
1534 | } | |
784c1454 | 1535 | ubi_ro_mode(ubi); |
801c135c AB |
1536 | return err; |
1537 | } | |
1538 | ||
1539 | /** | |
85c6e6e2 | 1540 | * ubi_wl_put_peb - return a PEB to the wear-leveling sub-system. |
801c135c | 1541 | * @ubi: UBI device description object |
d36e59e6 JR |
1542 | * @vol_id: the volume ID that last used this PEB |
1543 | * @lnum: the last used logical eraseblock number for the PEB | |
801c135c AB |
1544 | * @pnum: physical eraseblock to return |
1545 | * @torture: if this physical eraseblock has to be tortured | |
1546 | * | |
1547 | * This function is called to return physical eraseblock @pnum to the pool of | |
1548 | * free physical eraseblocks. The @torture flag has to be set if an I/O error | |
1549 | * occurred to this @pnum and it has to be tested. This function returns zero | |
43f9b25a | 1550 | * in case of success, and a negative error code in case of failure. |
801c135c | 1551 | */ |
d36e59e6 JR |
1552 | int ubi_wl_put_peb(struct ubi_device *ubi, int vol_id, int lnum, |
1553 | int pnum, int torture) | |
801c135c AB |
1554 | { |
1555 | int err; | |
1556 | struct ubi_wl_entry *e; | |
1557 | ||
1558 | dbg_wl("PEB %d", pnum); | |
1559 | ubi_assert(pnum >= 0); | |
1560 | ubi_assert(pnum < ubi->peb_count); | |
1561 | ||
43f9b25a | 1562 | retry: |
801c135c | 1563 | spin_lock(&ubi->wl_lock); |
801c135c AB |
1564 | e = ubi->lookuptbl[pnum]; |
1565 | if (e == ubi->move_from) { | |
1566 | /* | |
1567 | * User is putting the physical eraseblock which was selected to | |
1568 | * be moved. It will be scheduled for erasure in the | |
1569 | * wear-leveling worker. | |
1570 | */ | |
43f9b25a | 1571 | dbg_wl("PEB %d is being moved, wait", pnum); |
801c135c | 1572 | spin_unlock(&ubi->wl_lock); |
43f9b25a AB |
1573 | |
1574 | /* Wait for the WL worker by taking the @ubi->move_mutex */ | |
1575 | mutex_lock(&ubi->move_mutex); | |
1576 | mutex_unlock(&ubi->move_mutex); | |
1577 | goto retry; | |
801c135c AB |
1578 | } else if (e == ubi->move_to) { |
1579 | /* | |
1580 | * User is putting the physical eraseblock which was selected | |
1581 | * as the target the data is moved to. It may happen if the EBA | |
85c6e6e2 AB |
1582 | * sub-system already re-mapped the LEB in 'ubi_eba_copy_leb()' |
1583 | * but the WL sub-system has not put the PEB to the "used" tree | |
1584 | * yet, but it is about to do this. So we just set a flag which | |
1585 | * will tell the WL worker that the PEB is not needed anymore | |
1586 | * and should be scheduled for erasure. | |
801c135c AB |
1587 | */ |
1588 | dbg_wl("PEB %d is the target of data moving", pnum); | |
1589 | ubi_assert(!ubi->move_to_put); | |
1590 | ubi->move_to_put = 1; | |
1591 | spin_unlock(&ubi->wl_lock); | |
1592 | return 0; | |
1593 | } else { | |
5abde384 | 1594 | if (in_wl_tree(e, &ubi->used)) { |
7bf523ae | 1595 | self_check_in_wl_tree(ubi, e, &ubi->used); |
23553b2c | 1596 | rb_erase(&e->u.rb, &ubi->used); |
5abde384 | 1597 | } else if (in_wl_tree(e, &ubi->scrub)) { |
7bf523ae | 1598 | self_check_in_wl_tree(ubi, e, &ubi->scrub); |
23553b2c | 1599 | rb_erase(&e->u.rb, &ubi->scrub); |
b86a2c56 | 1600 | } else if (in_wl_tree(e, &ubi->erroneous)) { |
7bf523ae | 1601 | self_check_in_wl_tree(ubi, e, &ubi->erroneous); |
b86a2c56 AB |
1602 | rb_erase(&e->u.rb, &ubi->erroneous); |
1603 | ubi->erroneous_peb_count -= 1; | |
1604 | ubi_assert(ubi->erroneous_peb_count >= 0); | |
815bc5f8 | 1605 | /* Erroneous PEBs should be tortured */ |
b86a2c56 | 1606 | torture = 1; |
43f9b25a | 1607 | } else { |
7b6c32da | 1608 | err = prot_queue_del(ubi, e->pnum); |
43f9b25a AB |
1609 | if (err) { |
1610 | ubi_err("PEB %d not found", pnum); | |
1611 | ubi_ro_mode(ubi); | |
1612 | spin_unlock(&ubi->wl_lock); | |
1613 | return err; | |
1614 | } | |
1615 | } | |
801c135c AB |
1616 | } |
1617 | spin_unlock(&ubi->wl_lock); | |
1618 | ||
d36e59e6 | 1619 | err = schedule_erase(ubi, e, vol_id, lnum, torture); |
801c135c AB |
1620 | if (err) { |
1621 | spin_lock(&ubi->wl_lock); | |
5abde384 | 1622 | wl_tree_add(e, &ubi->used); |
801c135c AB |
1623 | spin_unlock(&ubi->wl_lock); |
1624 | } | |
1625 | ||
1626 | return err; | |
1627 | } | |
1628 | ||
1629 | /** | |
1630 | * ubi_wl_scrub_peb - schedule a physical eraseblock for scrubbing. | |
1631 | * @ubi: UBI device description object | |
1632 | * @pnum: the physical eraseblock to schedule | |
1633 | * | |
1634 | * If a bit-flip in a physical eraseblock is detected, this physical eraseblock | |
1635 | * needs scrubbing. This function schedules a physical eraseblock for | |
1636 | * scrubbing which is done in background. This function returns zero in case of | |
1637 | * success and a negative error code in case of failure. | |
1638 | */ | |
1639 | int ubi_wl_scrub_peb(struct ubi_device *ubi, int pnum) | |
1640 | { | |
1641 | struct ubi_wl_entry *e; | |
1642 | ||
719bb840 | 1643 | ubi_msg("schedule PEB %d for scrubbing", pnum); |
801c135c AB |
1644 | |
1645 | retry: | |
1646 | spin_lock(&ubi->wl_lock); | |
1647 | e = ubi->lookuptbl[pnum]; | |
d3f6e6c6 AB |
1648 | if (e == ubi->move_from || in_wl_tree(e, &ubi->scrub) || |
1649 | in_wl_tree(e, &ubi->erroneous)) { | |
801c135c AB |
1650 | spin_unlock(&ubi->wl_lock); |
1651 | return 0; | |
1652 | } | |
1653 | ||
1654 | if (e == ubi->move_to) { | |
1655 | /* | |
1656 | * This physical eraseblock was used to move data to. The data | |
1657 | * was moved but the PEB was not yet inserted to the proper | |
1658 | * tree. We should just wait a little and let the WL worker | |
1659 | * proceed. | |
1660 | */ | |
1661 | spin_unlock(&ubi->wl_lock); | |
1662 | dbg_wl("the PEB %d is not in proper tree, retry", pnum); | |
1663 | yield(); | |
1664 | goto retry; | |
1665 | } | |
1666 | ||
5abde384 | 1667 | if (in_wl_tree(e, &ubi->used)) { |
7bf523ae | 1668 | self_check_in_wl_tree(ubi, e, &ubi->used); |
23553b2c | 1669 | rb_erase(&e->u.rb, &ubi->used); |
43f9b25a AB |
1670 | } else { |
1671 | int err; | |
1672 | ||
7b6c32da | 1673 | err = prot_queue_del(ubi, e->pnum); |
43f9b25a AB |
1674 | if (err) { |
1675 | ubi_err("PEB %d not found", pnum); | |
1676 | ubi_ro_mode(ubi); | |
1677 | spin_unlock(&ubi->wl_lock); | |
1678 | return err; | |
1679 | } | |
1680 | } | |
801c135c | 1681 | |
5abde384 | 1682 | wl_tree_add(e, &ubi->scrub); |
801c135c AB |
1683 | spin_unlock(&ubi->wl_lock); |
1684 | ||
1685 | /* | |
1686 | * Technically scrubbing is the same as wear-leveling, so it is done | |
1687 | * by the WL worker. | |
1688 | */ | |
8199b901 | 1689 | return ensure_wear_leveling(ubi, 0); |
801c135c AB |
1690 | } |
1691 | ||
1692 | /** | |
1693 | * ubi_wl_flush - flush all pending works. | |
1694 | * @ubi: UBI device description object | |
62f38455 JR |
1695 | * @vol_id: the volume id to flush for |
1696 | * @lnum: the logical eraseblock number to flush for | |
801c135c | 1697 | * |
62f38455 JR |
1698 | * This function executes all pending works for a particular volume id / |
1699 | * logical eraseblock number pair. If either value is set to %UBI_ALL, then it | |
1700 | * acts as a wildcard for all of the corresponding volume numbers or logical | |
1701 | * eraseblock numbers. It returns zero in case of success and a negative error | |
1702 | * code in case of failure. | |
801c135c | 1703 | */ |
62f38455 | 1704 | int ubi_wl_flush(struct ubi_device *ubi, int vol_id, int lnum) |
801c135c | 1705 | { |
62f38455 JR |
1706 | int err = 0; |
1707 | int found = 1; | |
801c135c AB |
1708 | |
1709 | /* | |
7b6c32da | 1710 | * Erase while the pending works queue is not empty, but not more than |
801c135c AB |
1711 | * the number of currently pending works. |
1712 | */ | |
62f38455 JR |
1713 | dbg_wl("flush pending work for LEB %d:%d (%d pending works)", |
1714 | vol_id, lnum, ubi->works_count); | |
593dd33c | 1715 | |
62f38455 JR |
1716 | while (found) { |
1717 | struct ubi_work *wrk; | |
1718 | found = 0; | |
593dd33c | 1719 | |
12027f1b | 1720 | down_read(&ubi->work_sem); |
62f38455 JR |
1721 | spin_lock(&ubi->wl_lock); |
1722 | list_for_each_entry(wrk, &ubi->works, list) { | |
1723 | if ((vol_id == UBI_ALL || wrk->vol_id == vol_id) && | |
1724 | (lnum == UBI_ALL || wrk->lnum == lnum)) { | |
1725 | list_del(&wrk->list); | |
1726 | ubi->works_count -= 1; | |
1727 | ubi_assert(ubi->works_count >= 0); | |
1728 | spin_unlock(&ubi->wl_lock); | |
1729 | ||
1730 | err = wrk->func(ubi, wrk, 0); | |
12027f1b AB |
1731 | if (err) { |
1732 | up_read(&ubi->work_sem); | |
1733 | return err; | |
1734 | } | |
1735 | ||
62f38455 JR |
1736 | spin_lock(&ubi->wl_lock); |
1737 | found = 1; | |
1738 | break; | |
1739 | } | |
1740 | } | |
1741 | spin_unlock(&ubi->wl_lock); | |
12027f1b | 1742 | up_read(&ubi->work_sem); |
801c135c AB |
1743 | } |
1744 | ||
12027f1b AB |
1745 | /* |
1746 | * Make sure all the works which have been done in parallel are | |
1747 | * finished. | |
1748 | */ | |
1749 | down_write(&ubi->work_sem); | |
62f38455 | 1750 | up_write(&ubi->work_sem); |
12027f1b | 1751 | |
62f38455 | 1752 | return err; |
801c135c AB |
1753 | } |
1754 | ||
1755 | /** | |
1756 | * tree_destroy - destroy an RB-tree. | |
1757 | * @root: the root of the tree to destroy | |
1758 | */ | |
1759 | static void tree_destroy(struct rb_root *root) | |
1760 | { | |
1761 | struct rb_node *rb; | |
1762 | struct ubi_wl_entry *e; | |
1763 | ||
1764 | rb = root->rb_node; | |
1765 | while (rb) { | |
1766 | if (rb->rb_left) | |
1767 | rb = rb->rb_left; | |
1768 | else if (rb->rb_right) | |
1769 | rb = rb->rb_right; | |
1770 | else { | |
23553b2c | 1771 | e = rb_entry(rb, struct ubi_wl_entry, u.rb); |
801c135c AB |
1772 | |
1773 | rb = rb_parent(rb); | |
1774 | if (rb) { | |
23553b2c | 1775 | if (rb->rb_left == &e->u.rb) |
801c135c AB |
1776 | rb->rb_left = NULL; |
1777 | else | |
1778 | rb->rb_right = NULL; | |
1779 | } | |
1780 | ||
06b68ba1 | 1781 | kmem_cache_free(ubi_wl_entry_slab, e); |
801c135c AB |
1782 | } |
1783 | } | |
1784 | } | |
1785 | ||
1786 | /** | |
1787 | * ubi_thread - UBI background thread. | |
1788 | * @u: the UBI device description object pointer | |
1789 | */ | |
cdfa788a | 1790 | int ubi_thread(void *u) |
801c135c AB |
1791 | { |
1792 | int failures = 0; | |
1793 | struct ubi_device *ubi = u; | |
1794 | ||
1795 | ubi_msg("background thread \"%s\" started, PID %d", | |
ba25f9dc | 1796 | ubi->bgt_name, task_pid_nr(current)); |
801c135c | 1797 | |
83144186 | 1798 | set_freezable(); |
801c135c AB |
1799 | for (;;) { |
1800 | int err; | |
1801 | ||
1802 | if (kthread_should_stop()) | |
cadb40cc | 1803 | break; |
801c135c AB |
1804 | |
1805 | if (try_to_freeze()) | |
1806 | continue; | |
1807 | ||
1808 | spin_lock(&ubi->wl_lock); | |
1809 | if (list_empty(&ubi->works) || ubi->ro_mode || | |
27a0f2a3 | 1810 | !ubi->thread_enabled || ubi_dbg_is_bgt_disabled(ubi)) { |
801c135c AB |
1811 | set_current_state(TASK_INTERRUPTIBLE); |
1812 | spin_unlock(&ubi->wl_lock); | |
1813 | schedule(); | |
1814 | continue; | |
1815 | } | |
1816 | spin_unlock(&ubi->wl_lock); | |
1817 | ||
1818 | err = do_work(ubi); | |
1819 | if (err) { | |
1820 | ubi_err("%s: work failed with error code %d", | |
1821 | ubi->bgt_name, err); | |
1822 | if (failures++ > WL_MAX_FAILURES) { | |
1823 | /* | |
1824 | * Too many failures, disable the thread and | |
1825 | * switch to read-only mode. | |
1826 | */ | |
1827 | ubi_msg("%s: %d consecutive failures", | |
1828 | ubi->bgt_name, WL_MAX_FAILURES); | |
1829 | ubi_ro_mode(ubi); | |
2ad49887 VG |
1830 | ubi->thread_enabled = 0; |
1831 | continue; | |
801c135c AB |
1832 | } |
1833 | } else | |
1834 | failures = 0; | |
1835 | ||
1836 | cond_resched(); | |
1837 | } | |
1838 | ||
801c135c AB |
1839 | dbg_wl("background thread \"%s\" is killed", ubi->bgt_name); |
1840 | return 0; | |
1841 | } | |
1842 | ||
1843 | /** | |
1844 | * cancel_pending - cancel all pending works. | |
1845 | * @ubi: UBI device description object | |
1846 | */ | |
1847 | static void cancel_pending(struct ubi_device *ubi) | |
1848 | { | |
1849 | while (!list_empty(&ubi->works)) { | |
1850 | struct ubi_work *wrk; | |
1851 | ||
1852 | wrk = list_entry(ubi->works.next, struct ubi_work, list); | |
1853 | list_del(&wrk->list); | |
1854 | wrk->func(ubi, wrk, 1); | |
1855 | ubi->works_count -= 1; | |
1856 | ubi_assert(ubi->works_count >= 0); | |
1857 | } | |
1858 | } | |
1859 | ||
1860 | /** | |
41e0cd9d | 1861 | * ubi_wl_init - initialize the WL sub-system using attaching information. |
801c135c | 1862 | * @ubi: UBI device description object |
a4e6042f | 1863 | * @ai: attaching information |
801c135c AB |
1864 | * |
1865 | * This function returns zero in case of success, and a negative error code in | |
1866 | * case of failure. | |
1867 | */ | |
41e0cd9d | 1868 | int ubi_wl_init(struct ubi_device *ubi, struct ubi_attach_info *ai) |
801c135c | 1869 | { |
8199b901 | 1870 | int err, i, reserved_pebs, found_pebs = 0; |
801c135c | 1871 | struct rb_node *rb1, *rb2; |
517af48c | 1872 | struct ubi_ainf_volume *av; |
2c5ec5ce | 1873 | struct ubi_ainf_peb *aeb, *tmp; |
801c135c AB |
1874 | struct ubi_wl_entry *e; |
1875 | ||
b86a2c56 | 1876 | ubi->used = ubi->erroneous = ubi->free = ubi->scrub = RB_ROOT; |
801c135c | 1877 | spin_lock_init(&ubi->wl_lock); |
43f9b25a | 1878 | mutex_init(&ubi->move_mutex); |
593dd33c | 1879 | init_rwsem(&ubi->work_sem); |
a4e6042f | 1880 | ubi->max_ec = ai->max_ec; |
801c135c | 1881 | INIT_LIST_HEAD(&ubi->works); |
8199b901 RW |
1882 | #ifdef CONFIG_MTD_UBI_FASTMAP |
1883 | INIT_WORK(&ubi->fm_work, update_fastmap_work_fn); | |
1884 | #endif | |
801c135c AB |
1885 | |
1886 | sprintf(ubi->bgt_name, UBI_BGT_NAME_PATTERN, ubi->ubi_num); | |
1887 | ||
801c135c AB |
1888 | err = -ENOMEM; |
1889 | ubi->lookuptbl = kzalloc(ubi->peb_count * sizeof(void *), GFP_KERNEL); | |
1890 | if (!ubi->lookuptbl) | |
cdfa788a | 1891 | return err; |
801c135c | 1892 | |
7b6c32da XX |
1893 | for (i = 0; i < UBI_PROT_QUEUE_LEN; i++) |
1894 | INIT_LIST_HEAD(&ubi->pq[i]); | |
1895 | ubi->pq_head = 0; | |
1896 | ||
a4e6042f | 1897 | list_for_each_entry_safe(aeb, tmp, &ai->erase, u.list) { |
801c135c AB |
1898 | cond_resched(); |
1899 | ||
06b68ba1 | 1900 | e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL); |
801c135c AB |
1901 | if (!e) |
1902 | goto out_free; | |
1903 | ||
2c5ec5ce AB |
1904 | e->pnum = aeb->pnum; |
1905 | e->ec = aeb->ec; | |
8199b901 | 1906 | ubi_assert(!ubi_is_fm_block(ubi, e->pnum)); |
801c135c | 1907 | ubi->lookuptbl[e->pnum] = e; |
d36e59e6 | 1908 | if (schedule_erase(ubi, e, aeb->vol_id, aeb->lnum, 0)) { |
06b68ba1 | 1909 | kmem_cache_free(ubi_wl_entry_slab, e); |
801c135c AB |
1910 | goto out_free; |
1911 | } | |
8199b901 RW |
1912 | |
1913 | found_pebs++; | |
801c135c AB |
1914 | } |
1915 | ||
8199b901 | 1916 | ubi->free_count = 0; |
a4e6042f | 1917 | list_for_each_entry(aeb, &ai->free, u.list) { |
801c135c AB |
1918 | cond_resched(); |
1919 | ||
06b68ba1 | 1920 | e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL); |
801c135c AB |
1921 | if (!e) |
1922 | goto out_free; | |
1923 | ||
2c5ec5ce AB |
1924 | e->pnum = aeb->pnum; |
1925 | e->ec = aeb->ec; | |
801c135c | 1926 | ubi_assert(e->ec >= 0); |
8199b901 RW |
1927 | ubi_assert(!ubi_is_fm_block(ubi, e->pnum)); |
1928 | ||
5abde384 | 1929 | wl_tree_add(e, &ubi->free); |
8199b901 RW |
1930 | ubi->free_count++; |
1931 | ||
801c135c | 1932 | ubi->lookuptbl[e->pnum] = e; |
8199b901 RW |
1933 | |
1934 | found_pebs++; | |
801c135c AB |
1935 | } |
1936 | ||
517af48c AB |
1937 | ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb) { |
1938 | ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb) { | |
801c135c AB |
1939 | cond_resched(); |
1940 | ||
06b68ba1 | 1941 | e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL); |
801c135c AB |
1942 | if (!e) |
1943 | goto out_free; | |
1944 | ||
2c5ec5ce AB |
1945 | e->pnum = aeb->pnum; |
1946 | e->ec = aeb->ec; | |
801c135c | 1947 | ubi->lookuptbl[e->pnum] = e; |
8199b901 | 1948 | |
2c5ec5ce | 1949 | if (!aeb->scrub) { |
801c135c AB |
1950 | dbg_wl("add PEB %d EC %d to the used tree", |
1951 | e->pnum, e->ec); | |
5abde384 | 1952 | wl_tree_add(e, &ubi->used); |
801c135c AB |
1953 | } else { |
1954 | dbg_wl("add PEB %d EC %d to the scrub tree", | |
1955 | e->pnum, e->ec); | |
5abde384 | 1956 | wl_tree_add(e, &ubi->scrub); |
801c135c | 1957 | } |
8199b901 RW |
1958 | |
1959 | found_pebs++; | |
801c135c AB |
1960 | } |
1961 | } | |
1962 | ||
8199b901 RW |
1963 | dbg_wl("found %i PEBs", found_pebs); |
1964 | ||
1965 | if (ubi->fm) | |
1966 | ubi_assert(ubi->good_peb_count == \ | |
1967 | found_pebs + ubi->fm->used_blocks); | |
1968 | else | |
1969 | ubi_assert(ubi->good_peb_count == found_pebs); | |
1970 | ||
1971 | reserved_pebs = WL_RESERVED_PEBS; | |
1972 | #ifdef CONFIG_MTD_UBI_FASTMAP | |
1973 | /* Reserve enough LEBs to store two fastmaps. */ | |
1974 | reserved_pebs += (ubi->fm_size / ubi->leb_size) * 2; | |
1975 | #endif | |
1976 | ||
1977 | if (ubi->avail_pebs < reserved_pebs) { | |
801c135c | 1978 | ubi_err("no enough physical eraseblocks (%d, need %d)", |
8199b901 | 1979 | ubi->avail_pebs, reserved_pebs); |
5fc01ab6 AB |
1980 | if (ubi->corr_peb_count) |
1981 | ubi_err("%d PEBs are corrupted and not used", | |
1982 | ubi->corr_peb_count); | |
801c135c AB |
1983 | goto out_free; |
1984 | } | |
8199b901 RW |
1985 | ubi->avail_pebs -= reserved_pebs; |
1986 | ubi->rsvd_pebs += reserved_pebs; | |
801c135c AB |
1987 | |
1988 | /* Schedule wear-leveling if needed */ | |
8199b901 | 1989 | err = ensure_wear_leveling(ubi, 0); |
801c135c AB |
1990 | if (err) |
1991 | goto out_free; | |
1992 | ||
1993 | return 0; | |
1994 | ||
1995 | out_free: | |
1996 | cancel_pending(ubi); | |
1997 | tree_destroy(&ubi->used); | |
1998 | tree_destroy(&ubi->free); | |
1999 | tree_destroy(&ubi->scrub); | |
2000 | kfree(ubi->lookuptbl); | |
801c135c AB |
2001 | return err; |
2002 | } | |
2003 | ||
2004 | /** | |
7b6c32da | 2005 | * protection_queue_destroy - destroy the protection queue. |
801c135c AB |
2006 | * @ubi: UBI device description object |
2007 | */ | |
7b6c32da | 2008 | static void protection_queue_destroy(struct ubi_device *ubi) |
801c135c | 2009 | { |
7b6c32da XX |
2010 | int i; |
2011 | struct ubi_wl_entry *e, *tmp; | |
801c135c | 2012 | |
7b6c32da XX |
2013 | for (i = 0; i < UBI_PROT_QUEUE_LEN; ++i) { |
2014 | list_for_each_entry_safe(e, tmp, &ubi->pq[i], u.list) { | |
2015 | list_del(&e->u.list); | |
2016 | kmem_cache_free(ubi_wl_entry_slab, e); | |
801c135c AB |
2017 | } |
2018 | } | |
2019 | } | |
2020 | ||
2021 | /** | |
85c6e6e2 | 2022 | * ubi_wl_close - close the wear-leveling sub-system. |
801c135c AB |
2023 | * @ubi: UBI device description object |
2024 | */ | |
2025 | void ubi_wl_close(struct ubi_device *ubi) | |
2026 | { | |
85c6e6e2 | 2027 | dbg_wl("close the WL sub-system"); |
801c135c | 2028 | cancel_pending(ubi); |
7b6c32da | 2029 | protection_queue_destroy(ubi); |
801c135c | 2030 | tree_destroy(&ubi->used); |
b86a2c56 | 2031 | tree_destroy(&ubi->erroneous); |
801c135c AB |
2032 | tree_destroy(&ubi->free); |
2033 | tree_destroy(&ubi->scrub); | |
2034 | kfree(ubi->lookuptbl); | |
801c135c AB |
2035 | } |
2036 | ||
801c135c | 2037 | /** |
7bf523ae | 2038 | * self_check_ec - make sure that the erase counter of a PEB is correct. |
801c135c AB |
2039 | * @ubi: UBI device description object |
2040 | * @pnum: the physical eraseblock number to check | |
2041 | * @ec: the erase counter to check | |
2042 | * | |
2043 | * This function returns zero if the erase counter of physical eraseblock @pnum | |
feddbb34 AB |
2044 | * is equivalent to @ec, and a negative error code if not or if an error |
2045 | * occurred. | |
801c135c | 2046 | */ |
7bf523ae | 2047 | static int self_check_ec(struct ubi_device *ubi, int pnum, int ec) |
801c135c AB |
2048 | { |
2049 | int err; | |
2050 | long long read_ec; | |
2051 | struct ubi_ec_hdr *ec_hdr; | |
2052 | ||
2a734bb8 | 2053 | if (!ubi->dbg->chk_gen) |
92d124f5 AB |
2054 | return 0; |
2055 | ||
33818bbb | 2056 | ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_NOFS); |
801c135c AB |
2057 | if (!ec_hdr) |
2058 | return -ENOMEM; | |
2059 | ||
2060 | err = ubi_io_read_ec_hdr(ubi, pnum, ec_hdr, 0); | |
2061 | if (err && err != UBI_IO_BITFLIPS) { | |
2062 | /* The header does not have to exist */ | |
2063 | err = 0; | |
2064 | goto out_free; | |
2065 | } | |
2066 | ||
3261ebd7 | 2067 | read_ec = be64_to_cpu(ec_hdr->ec); |
8199b901 | 2068 | if (ec != read_ec && read_ec - ec > 1) { |
7bf523ae | 2069 | ubi_err("self-check failed for PEB %d", pnum); |
801c135c | 2070 | ubi_err("read EC is %lld, should be %d", read_ec, ec); |
25886a36 | 2071 | dump_stack(); |
801c135c AB |
2072 | err = 1; |
2073 | } else | |
2074 | err = 0; | |
2075 | ||
2076 | out_free: | |
2077 | kfree(ec_hdr); | |
2078 | return err; | |
2079 | } | |
2080 | ||
2081 | /** | |
7bf523ae | 2082 | * self_check_in_wl_tree - check that wear-leveling entry is in WL RB-tree. |
d99383b0 | 2083 | * @ubi: UBI device description object |
801c135c AB |
2084 | * @e: the wear-leveling entry to check |
2085 | * @root: the root of the tree | |
2086 | * | |
adbf05e3 AB |
2087 | * This function returns zero if @e is in the @root RB-tree and %-EINVAL if it |
2088 | * is not. | |
801c135c | 2089 | */ |
7bf523ae AB |
2090 | static int self_check_in_wl_tree(const struct ubi_device *ubi, |
2091 | struct ubi_wl_entry *e, struct rb_root *root) | |
801c135c | 2092 | { |
2a734bb8 | 2093 | if (!ubi->dbg->chk_gen) |
92d124f5 AB |
2094 | return 0; |
2095 | ||
801c135c AB |
2096 | if (in_wl_tree(e, root)) |
2097 | return 0; | |
2098 | ||
7bf523ae | 2099 | ubi_err("self-check failed for PEB %d, EC %d, RB-tree %p ", |
801c135c | 2100 | e->pnum, e->ec, root); |
25886a36 | 2101 | dump_stack(); |
adbf05e3 | 2102 | return -EINVAL; |
801c135c AB |
2103 | } |
2104 | ||
7b6c32da | 2105 | /** |
7bf523ae | 2106 | * self_check_in_pq - check if wear-leveling entry is in the protection |
7b6c32da XX |
2107 | * queue. |
2108 | * @ubi: UBI device description object | |
2109 | * @e: the wear-leveling entry to check | |
2110 | * | |
adbf05e3 | 2111 | * This function returns zero if @e is in @ubi->pq and %-EINVAL if it is not. |
7b6c32da | 2112 | */ |
7bf523ae AB |
2113 | static int self_check_in_pq(const struct ubi_device *ubi, |
2114 | struct ubi_wl_entry *e) | |
7b6c32da XX |
2115 | { |
2116 | struct ubi_wl_entry *p; | |
2117 | int i; | |
2118 | ||
2a734bb8 | 2119 | if (!ubi->dbg->chk_gen) |
92d124f5 AB |
2120 | return 0; |
2121 | ||
7b6c32da XX |
2122 | for (i = 0; i < UBI_PROT_QUEUE_LEN; ++i) |
2123 | list_for_each_entry(p, &ubi->pq[i], u.list) | |
2124 | if (p == e) | |
2125 | return 0; | |
2126 | ||
7bf523ae | 2127 | ubi_err("self-check failed for PEB %d, EC %d, Protect queue", |
7b6c32da | 2128 | e->pnum, e->ec); |
25886a36 | 2129 | dump_stack(); |
adbf05e3 | 2130 | return -EINVAL; |
7b6c32da | 2131 | } |