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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 | /* | |
85c6e6e2 | 22 | * UBI wear-leveling sub-system. |
801c135c | 23 | * |
85c6e6e2 | 24 | * This sub-system is responsible for wear-leveling. It works in terms of |
7b6c32da | 25 | * physical eraseblocks and erase counters and knows nothing about logical |
85c6e6e2 AB |
26 | * eraseblocks, volumes, etc. From this sub-system's perspective all physical |
27 | * eraseblocks are of two types - used and free. Used physical eraseblocks are | |
28 | * those that were "get" by the 'ubi_wl_get_peb()' function, and free physical | |
29 | * eraseblocks are those that were put by the 'ubi_wl_put_peb()' function. | |
801c135c AB |
30 | * |
31 | * Physical eraseblocks returned by 'ubi_wl_get_peb()' have only erase counter | |
85c6e6e2 | 32 | * header. The rest of the physical eraseblock contains only %0xFF bytes. |
801c135c | 33 | * |
85c6e6e2 | 34 | * When physical eraseblocks are returned to the WL sub-system by means of the |
801c135c AB |
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, | |
85c6e6e2 | 37 | * which is also managed by the WL sub-system. |
801c135c AB |
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 | * | |
85c6e6e2 AB |
43 | * If the WL sub-system fails to erase a physical eraseblock, it marks it as |
44 | * bad. | |
801c135c | 45 | * |
85c6e6e2 AB |
46 | * This sub-system is also responsible for scrubbing. If a bit-flip is detected |
47 | * in a physical eraseblock, it has to be moved. Technically this is the same | |
48 | * as moving it for wear-leveling reasons. | |
801c135c | 49 | * |
85c6e6e2 AB |
50 | * As it was said, for the UBI sub-system all physical eraseblocks are either |
51 | * "free" or "used". Free eraseblock are kept in the @wl->free RB-tree, while | |
b86a2c56 AB |
52 | * used eraseblocks are kept in @wl->used, @wl->erroneous, or @wl->scrub |
53 | * RB-trees, as well as (temporarily) in the @wl->pq queue. | |
7b6c32da XX |
54 | * |
55 | * When the WL sub-system returns a physical eraseblock, the physical | |
56 | * eraseblock is protected from being moved for some "time". For this reason, | |
57 | * the physical eraseblock is not directly moved from the @wl->free tree to the | |
58 | * @wl->used tree. There is a protection queue in between where this | |
59 | * physical eraseblock is temporarily stored (@wl->pq). | |
60 | * | |
61 | * All this protection stuff is needed because: | |
62 | * o we don't want to move physical eraseblocks just after we have given them | |
63 | * to the user; instead, we first want to let users fill them up with data; | |
64 | * | |
65 | * o there is a chance that the user will put the physical eraseblock very | |
44156267 | 66 | * soon, so it makes sense not to move it for some time, but wait. |
7b6c32da XX |
67 | * |
68 | * Physical eraseblocks stay protected only for limited time. But the "time" is | |
69 | * measured in erase cycles in this case. This is implemented with help of the | |
70 | * protection queue. Eraseblocks are put to the tail of this queue when they | |
71 | * are returned by the 'ubi_wl_get_peb()', and eraseblocks are removed from the | |
72 | * head of the queue on each erase operation (for any eraseblock). So the | |
73 | * length of the queue defines how may (global) erase cycles PEBs are protected. | |
74 | * | |
75 | * To put it differently, each physical eraseblock has 2 main states: free and | |
76 | * used. The former state corresponds to the @wl->free tree. The latter state | |
77 | * is split up on several sub-states: | |
78 | * o the WL movement is allowed (@wl->used tree); | |
815bc5f8 | 79 | * o the WL movement is disallowed (@wl->erroneous) because the PEB is |
b86a2c56 | 80 | * erroneous - e.g., there was a read error; |
7b6c32da XX |
81 | * o the WL movement is temporarily prohibited (@wl->pq queue); |
82 | * o scrubbing is needed (@wl->scrub tree). | |
83 | * | |
84 | * Depending on the sub-state, wear-leveling entries of the used physical | |
85 | * eraseblocks may be kept in one of those structures. | |
801c135c AB |
86 | * |
87 | * Note, in this implementation, we keep a small in-RAM object for each physical | |
88 | * eraseblock. This is surely not a scalable solution. But it appears to be good | |
89 | * enough for moderately large flashes and it is simple. In future, one may | |
85c6e6e2 | 90 | * re-work this sub-system and make it more scalable. |
801c135c | 91 | * |
85c6e6e2 AB |
92 | * At the moment this sub-system does not utilize the sequence number, which |
93 | * was introduced relatively recently. But it would be wise to do this because | |
94 | * the sequence number of a logical eraseblock characterizes how old is it. For | |
801c135c AB |
95 | * example, when we move a PEB with low erase counter, and we need to pick the |
96 | * target PEB, we pick a PEB with the highest EC if our PEB is "old" and we | |
97 | * pick target PEB with an average EC if our PEB is not very "old". This is a | |
85c6e6e2 | 98 | * room for future re-works of the WL sub-system. |
801c135c AB |
99 | */ |
100 | ||
101 | #include <linux/slab.h> | |
102 | #include <linux/crc32.h> | |
103 | #include <linux/freezer.h> | |
104 | #include <linux/kthread.h> | |
105 | #include "ubi.h" | |
106 | ||
107 | /* Number of physical eraseblocks reserved for wear-leveling purposes */ | |
108 | #define WL_RESERVED_PEBS 1 | |
109 | ||
801c135c AB |
110 | /* |
111 | * Maximum difference between two erase counters. If this threshold is | |
85c6e6e2 AB |
112 | * exceeded, the WL sub-system starts moving data from used physical |
113 | * eraseblocks with low erase counter to free physical eraseblocks with high | |
114 | * erase counter. | |
801c135c AB |
115 | */ |
116 | #define UBI_WL_THRESHOLD CONFIG_MTD_UBI_WL_THRESHOLD | |
117 | ||
118 | /* | |
85c6e6e2 | 119 | * When a physical eraseblock is moved, the WL sub-system has to pick the target |
801c135c AB |
120 | * physical eraseblock to move to. The simplest way would be just to pick the |
121 | * one with the highest erase counter. But in certain workloads this could lead | |
122 | * to an unlimited wear of one or few physical eraseblock. Indeed, imagine a | |
123 | * situation when the picked physical eraseblock is constantly erased after the | |
124 | * data is written to it. So, we have a constant which limits the highest erase | |
85c6e6e2 | 125 | * counter of the free physical eraseblock to pick. Namely, the WL sub-system |
025dfdaf | 126 | * does not pick eraseblocks with erase counter greater than the lowest erase |
801c135c AB |
127 | * counter plus %WL_FREE_MAX_DIFF. |
128 | */ | |
129 | #define WL_FREE_MAX_DIFF (2*UBI_WL_THRESHOLD) | |
130 | ||
131 | /* | |
132 | * Maximum number of consecutive background thread failures which is enough to | |
133 | * switch to read-only mode. | |
134 | */ | |
135 | #define WL_MAX_FAILURES 32 | |
136 | ||
7bf523ae AB |
137 | static int self_check_ec(struct ubi_device *ubi, int pnum, int ec); |
138 | static int self_check_in_wl_tree(const struct ubi_device *ubi, | |
139 | struct ubi_wl_entry *e, struct rb_root *root); | |
140 | static int self_check_in_pq(const struct ubi_device *ubi, | |
141 | struct ubi_wl_entry *e); | |
801c135c | 142 | |
8199b901 RW |
143 | #ifdef CONFIG_MTD_UBI_FASTMAP |
144 | /** | |
145 | * update_fastmap_work_fn - calls ubi_update_fastmap from a work queue | |
146 | * @wrk: the work description object | |
147 | */ | |
148 | static void update_fastmap_work_fn(struct work_struct *wrk) | |
149 | { | |
150 | struct ubi_device *ubi = container_of(wrk, struct ubi_device, fm_work); | |
151 | ubi_update_fastmap(ubi); | |
152 | } | |
153 | ||
154 | /** | |
155 | * ubi_ubi_is_fm_block - returns 1 if a PEB is currently used in a fastmap. | |
156 | * @ubi: UBI device description object | |
157 | * @pnum: the to be checked PEB | |
158 | */ | |
159 | static int ubi_is_fm_block(struct ubi_device *ubi, int pnum) | |
160 | { | |
161 | int i; | |
162 | ||
163 | if (!ubi->fm) | |
164 | return 0; | |
165 | ||
166 | for (i = 0; i < ubi->fm->used_blocks; i++) | |
167 | if (ubi->fm->e[i]->pnum == pnum) | |
168 | return 1; | |
169 | ||
170 | return 0; | |
171 | } | |
172 | #else | |
173 | static int ubi_is_fm_block(struct ubi_device *ubi, int pnum) | |
174 | { | |
175 | return 0; | |
176 | } | |
177 | #endif | |
178 | ||
801c135c AB |
179 | /** |
180 | * wl_tree_add - add a wear-leveling entry to a WL RB-tree. | |
181 | * @e: the wear-leveling entry to add | |
182 | * @root: the root of the tree | |
183 | * | |
184 | * Note, we use (erase counter, physical eraseblock number) pairs as keys in | |
185 | * the @ubi->used and @ubi->free RB-trees. | |
186 | */ | |
187 | static void wl_tree_add(struct ubi_wl_entry *e, struct rb_root *root) | |
188 | { | |
189 | struct rb_node **p, *parent = NULL; | |
190 | ||
191 | p = &root->rb_node; | |
192 | while (*p) { | |
193 | struct ubi_wl_entry *e1; | |
194 | ||
195 | parent = *p; | |
23553b2c | 196 | e1 = rb_entry(parent, struct ubi_wl_entry, u.rb); |
801c135c AB |
197 | |
198 | if (e->ec < e1->ec) | |
199 | p = &(*p)->rb_left; | |
200 | else if (e->ec > e1->ec) | |
201 | p = &(*p)->rb_right; | |
202 | else { | |
203 | ubi_assert(e->pnum != e1->pnum); | |
204 | if (e->pnum < e1->pnum) | |
205 | p = &(*p)->rb_left; | |
206 | else | |
207 | p = &(*p)->rb_right; | |
208 | } | |
209 | } | |
210 | ||
23553b2c XX |
211 | rb_link_node(&e->u.rb, parent, p); |
212 | rb_insert_color(&e->u.rb, root); | |
801c135c AB |
213 | } |
214 | ||
801c135c AB |
215 | /** |
216 | * do_work - do one pending work. | |
217 | * @ubi: UBI device description object | |
218 | * | |
219 | * This function returns zero in case of success and a negative error code in | |
220 | * case of failure. | |
221 | */ | |
222 | static int do_work(struct ubi_device *ubi) | |
223 | { | |
224 | int err; | |
225 | struct ubi_work *wrk; | |
226 | ||
43f9b25a AB |
227 | cond_resched(); |
228 | ||
593dd33c AB |
229 | /* |
230 | * @ubi->work_sem is used to synchronize with the workers. Workers take | |
231 | * it in read mode, so many of them may be doing works at a time. But | |
232 | * the queue flush code has to be sure the whole queue of works is | |
233 | * done, and it takes the mutex in write mode. | |
234 | */ | |
235 | down_read(&ubi->work_sem); | |
801c135c | 236 | spin_lock(&ubi->wl_lock); |
801c135c AB |
237 | if (list_empty(&ubi->works)) { |
238 | spin_unlock(&ubi->wl_lock); | |
593dd33c | 239 | up_read(&ubi->work_sem); |
801c135c AB |
240 | return 0; |
241 | } | |
242 | ||
243 | wrk = list_entry(ubi->works.next, struct ubi_work, list); | |
244 | list_del(&wrk->list); | |
16f557ec AB |
245 | ubi->works_count -= 1; |
246 | ubi_assert(ubi->works_count >= 0); | |
801c135c AB |
247 | spin_unlock(&ubi->wl_lock); |
248 | ||
249 | /* | |
250 | * Call the worker function. Do not touch the work structure | |
251 | * after this call as it will have been freed or reused by that | |
252 | * time by the worker function. | |
253 | */ | |
254 | err = wrk->func(ubi, wrk, 0); | |
255 | if (err) | |
256 | ubi_err("work failed with error code %d", err); | |
593dd33c | 257 | up_read(&ubi->work_sem); |
16f557ec | 258 | |
801c135c AB |
259 | return err; |
260 | } | |
261 | ||
262 | /** | |
263 | * produce_free_peb - produce a free physical eraseblock. | |
264 | * @ubi: UBI device description object | |
265 | * | |
266 | * This function tries to make a free PEB by means of synchronous execution of | |
267 | * pending works. This may be needed if, for example the background thread is | |
268 | * disabled. Returns zero in case of success and a negative error code in case | |
269 | * of failure. | |
270 | */ | |
271 | static int produce_free_peb(struct ubi_device *ubi) | |
272 | { | |
273 | int err; | |
274 | ||
5abde384 | 275 | while (!ubi->free.rb_node) { |
801c135c AB |
276 | spin_unlock(&ubi->wl_lock); |
277 | ||
278 | dbg_wl("do one work synchronously"); | |
279 | err = do_work(ubi); | |
801c135c AB |
280 | |
281 | spin_lock(&ubi->wl_lock); | |
8199b901 RW |
282 | if (err) |
283 | return err; | |
801c135c | 284 | } |
801c135c AB |
285 | |
286 | return 0; | |
287 | } | |
288 | ||
289 | /** | |
290 | * in_wl_tree - check if wear-leveling entry is present in a WL RB-tree. | |
291 | * @e: the wear-leveling entry to check | |
292 | * @root: the root of the tree | |
293 | * | |
294 | * This function returns non-zero if @e is in the @root RB-tree and zero if it | |
295 | * is not. | |
296 | */ | |
297 | static int in_wl_tree(struct ubi_wl_entry *e, struct rb_root *root) | |
298 | { | |
299 | struct rb_node *p; | |
300 | ||
301 | p = root->rb_node; | |
302 | while (p) { | |
303 | struct ubi_wl_entry *e1; | |
304 | ||
23553b2c | 305 | e1 = rb_entry(p, struct ubi_wl_entry, u.rb); |
801c135c AB |
306 | |
307 | if (e->pnum == e1->pnum) { | |
308 | ubi_assert(e == e1); | |
309 | return 1; | |
310 | } | |
311 | ||
312 | if (e->ec < e1->ec) | |
313 | p = p->rb_left; | |
314 | else if (e->ec > e1->ec) | |
315 | p = p->rb_right; | |
316 | else { | |
317 | ubi_assert(e->pnum != e1->pnum); | |
318 | if (e->pnum < e1->pnum) | |
319 | p = p->rb_left; | |
320 | else | |
321 | p = p->rb_right; | |
322 | } | |
323 | } | |
324 | ||
325 | return 0; | |
326 | } | |
327 | ||
328 | /** | |
7b6c32da | 329 | * prot_queue_add - add physical eraseblock to the protection queue. |
801c135c AB |
330 | * @ubi: UBI device description object |
331 | * @e: the physical eraseblock to add | |
801c135c | 332 | * |
7b6c32da XX |
333 | * This function adds @e to the tail of the protection queue @ubi->pq, where |
334 | * @e will stay for %UBI_PROT_QUEUE_LEN erase operations and will be | |
335 | * temporarily protected from the wear-leveling worker. Note, @wl->lock has to | |
336 | * be locked. | |
801c135c | 337 | */ |
7b6c32da | 338 | static void prot_queue_add(struct ubi_device *ubi, struct ubi_wl_entry *e) |
801c135c | 339 | { |
7b6c32da | 340 | int pq_tail = ubi->pq_head - 1; |
801c135c | 341 | |
7b6c32da XX |
342 | if (pq_tail < 0) |
343 | pq_tail = UBI_PROT_QUEUE_LEN - 1; | |
344 | ubi_assert(pq_tail >= 0 && pq_tail < UBI_PROT_QUEUE_LEN); | |
345 | list_add_tail(&e->u.list, &ubi->pq[pq_tail]); | |
346 | dbg_wl("added PEB %d EC %d to the protection queue", e->pnum, e->ec); | |
801c135c AB |
347 | } |
348 | ||
349 | /** | |
350 | * find_wl_entry - find wear-leveling entry closest to certain erase counter. | |
8199b901 | 351 | * @ubi: UBI device description object |
801c135c | 352 | * @root: the RB-tree where to look for |
add8287e | 353 | * @diff: maximum possible difference from the smallest erase counter |
801c135c AB |
354 | * |
355 | * This function looks for a wear leveling entry with erase counter closest to | |
add8287e | 356 | * min + @diff, where min is the smallest erase counter. |
801c135c | 357 | */ |
8199b901 RW |
358 | static struct ubi_wl_entry *find_wl_entry(struct ubi_device *ubi, |
359 | struct rb_root *root, int diff) | |
801c135c AB |
360 | { |
361 | struct rb_node *p; | |
8199b901 | 362 | struct ubi_wl_entry *e, *prev_e = NULL; |
add8287e | 363 | int max; |
801c135c | 364 | |
23553b2c | 365 | e = rb_entry(rb_first(root), struct ubi_wl_entry, u.rb); |
add8287e | 366 | max = e->ec + diff; |
801c135c AB |
367 | |
368 | p = root->rb_node; | |
369 | while (p) { | |
370 | struct ubi_wl_entry *e1; | |
371 | ||
23553b2c | 372 | e1 = rb_entry(p, struct ubi_wl_entry, u.rb); |
801c135c AB |
373 | if (e1->ec >= max) |
374 | p = p->rb_left; | |
375 | else { | |
376 | p = p->rb_right; | |
8199b901 | 377 | prev_e = e; |
801c135c AB |
378 | e = e1; |
379 | } | |
380 | } | |
381 | ||
8199b901 RW |
382 | /* If no fastmap has been written and this WL entry can be used |
383 | * as anchor PEB, hold it back and return the second best WL entry | |
384 | * such that fastmap can use the anchor PEB later. */ | |
385 | if (prev_e && !ubi->fm_disabled && | |
386 | !ubi->fm && e->pnum < UBI_FM_MAX_START) | |
387 | return prev_e; | |
388 | ||
801c135c AB |
389 | return e; |
390 | } | |
391 | ||
392 | /** | |
8199b901 RW |
393 | * find_mean_wl_entry - find wear-leveling entry with medium erase counter. |
394 | * @ubi: UBI device description object | |
395 | * @root: the RB-tree where to look for | |
396 | * | |
397 | * This function looks for a wear leveling entry with medium erase counter, | |
398 | * but not greater or equivalent than the lowest erase counter plus | |
399 | * %WL_FREE_MAX_DIFF/2. | |
400 | */ | |
401 | static struct ubi_wl_entry *find_mean_wl_entry(struct ubi_device *ubi, | |
402 | struct rb_root *root) | |
403 | { | |
404 | struct ubi_wl_entry *e, *first, *last; | |
405 | ||
406 | first = rb_entry(rb_first(root), struct ubi_wl_entry, u.rb); | |
407 | last = rb_entry(rb_last(root), struct ubi_wl_entry, u.rb); | |
408 | ||
409 | if (last->ec - first->ec < WL_FREE_MAX_DIFF) { | |
410 | e = rb_entry(root->rb_node, struct ubi_wl_entry, u.rb); | |
411 | ||
412 | #ifdef CONFIG_MTD_UBI_FASTMAP | |
413 | /* If no fastmap has been written and this WL entry can be used | |
414 | * as anchor PEB, hold it back and return the second best | |
415 | * WL entry such that fastmap can use the anchor PEB later. */ | |
416 | if (e && !ubi->fm_disabled && !ubi->fm && | |
417 | e->pnum < UBI_FM_MAX_START) | |
418 | e = rb_entry(rb_next(root->rb_node), | |
419 | struct ubi_wl_entry, u.rb); | |
420 | #endif | |
421 | } else | |
422 | e = find_wl_entry(ubi, root, WL_FREE_MAX_DIFF/2); | |
423 | ||
424 | return e; | |
425 | } | |
426 | ||
427 | #ifdef CONFIG_MTD_UBI_FASTMAP | |
428 | /** | |
429 | * find_anchor_wl_entry - find wear-leveling entry to used as anchor PEB. | |
430 | * @root: the RB-tree where to look for | |
431 | */ | |
432 | static struct ubi_wl_entry *find_anchor_wl_entry(struct rb_root *root) | |
433 | { | |
434 | struct rb_node *p; | |
435 | struct ubi_wl_entry *e, *victim = NULL; | |
436 | int max_ec = UBI_MAX_ERASECOUNTER; | |
437 | ||
438 | ubi_rb_for_each_entry(p, e, root, u.rb) { | |
439 | if (e->pnum < UBI_FM_MAX_START && e->ec < max_ec) { | |
440 | victim = e; | |
441 | max_ec = e->ec; | |
442 | } | |
443 | } | |
444 | ||
445 | return victim; | |
446 | } | |
447 | ||
448 | static int anchor_pebs_avalible(struct rb_root *root) | |
449 | { | |
450 | struct rb_node *p; | |
451 | struct ubi_wl_entry *e; | |
452 | ||
453 | ubi_rb_for_each_entry(p, e, root, u.rb) | |
454 | if (e->pnum < UBI_FM_MAX_START) | |
455 | return 1; | |
456 | ||
457 | return 0; | |
458 | } | |
459 | ||
460 | /** | |
461 | * ubi_wl_get_fm_peb - find a physical erase block with a given maximal number. | |
462 | * @ubi: UBI device description object | |
463 | * @anchor: This PEB will be used as anchor PEB by fastmap | |
464 | * | |
465 | * The function returns a physical erase block with a given maximal number | |
466 | * and removes it from the wl subsystem. | |
467 | * Must be called with wl_lock held! | |
468 | */ | |
469 | struct ubi_wl_entry *ubi_wl_get_fm_peb(struct ubi_device *ubi, int anchor) | |
470 | { | |
471 | struct ubi_wl_entry *e = NULL; | |
472 | ||
473 | if (!ubi->free.rb_node || (ubi->free_count - ubi->beb_rsvd_pebs < 1)) | |
474 | goto out; | |
475 | ||
476 | if (anchor) | |
477 | e = find_anchor_wl_entry(&ubi->free); | |
478 | else | |
479 | e = find_mean_wl_entry(ubi, &ubi->free); | |
480 | ||
481 | if (!e) | |
482 | goto out; | |
483 | ||
484 | self_check_in_wl_tree(ubi, e, &ubi->free); | |
485 | ||
486 | /* remove it from the free list, | |
487 | * the wl subsystem does no longer know this erase block */ | |
488 | rb_erase(&e->u.rb, &ubi->free); | |
489 | ubi->free_count--; | |
490 | out: | |
491 | return e; | |
492 | } | |
493 | #endif | |
494 | ||
495 | /** | |
496 | * __wl_get_peb - get a physical eraseblock. | |
801c135c | 497 | * @ubi: UBI device description object |
801c135c AB |
498 | * |
499 | * This function returns a physical eraseblock in case of success and a | |
894aef21 | 500 | * negative error code in case of failure. |
801c135c | 501 | */ |
8199b901 | 502 | static int __wl_get_peb(struct ubi_device *ubi) |
801c135c | 503 | { |
7eb3aa65 | 504 | int err; |
8199b901 | 505 | struct ubi_wl_entry *e; |
801c135c | 506 | |
801c135c | 507 | retry: |
5abde384 | 508 | if (!ubi->free.rb_node) { |
801c135c | 509 | if (ubi->works_count == 0) { |
801c135c | 510 | ubi_err("no free eraseblocks"); |
8199b901 | 511 | ubi_assert(list_empty(&ubi->works)); |
801c135c AB |
512 | return -ENOSPC; |
513 | } | |
801c135c AB |
514 | |
515 | err = produce_free_peb(ubi); | |
7b6c32da | 516 | if (err < 0) |
801c135c | 517 | return err; |
801c135c AB |
518 | goto retry; |
519 | } | |
520 | ||
8199b901 RW |
521 | e = find_mean_wl_entry(ubi, &ubi->free); |
522 | if (!e) { | |
523 | ubi_err("no free eraseblocks"); | |
524 | return -ENOSPC; | |
525 | } | |
801c135c | 526 | |
7bf523ae | 527 | self_check_in_wl_tree(ubi, e, &ubi->free); |
7b6c32da | 528 | |
801c135c | 529 | /* |
7b6c32da | 530 | * Move the physical eraseblock to the protection queue where it will |
801c135c AB |
531 | * be protected from being moved for some time. |
532 | */ | |
23553b2c | 533 | rb_erase(&e->u.rb, &ubi->free); |
8199b901 | 534 | ubi->free_count--; |
7b6c32da | 535 | dbg_wl("PEB %d EC %d", e->pnum, e->ec); |
8199b901 RW |
536 | #ifndef CONFIG_MTD_UBI_FASTMAP |
537 | /* We have to enqueue e only if fastmap is disabled, | |
538 | * is fastmap enabled prot_queue_add() will be called by | |
539 | * ubi_wl_get_peb() after removing e from the pool. */ | |
7b6c32da | 540 | prot_queue_add(ubi, e); |
8199b901 | 541 | #endif |
801c135c AB |
542 | return e->pnum; |
543 | } | |
544 | ||
8199b901 RW |
545 | #ifdef CONFIG_MTD_UBI_FASTMAP |
546 | /** | |
547 | * return_unused_pool_pebs - returns unused PEB to the free tree. | |
548 | * @ubi: UBI device description object | |
549 | * @pool: fastmap pool description object | |
550 | */ | |
551 | static void return_unused_pool_pebs(struct ubi_device *ubi, | |
552 | struct ubi_fm_pool *pool) | |
553 | { | |
554 | int i; | |
555 | struct ubi_wl_entry *e; | |
556 | ||
557 | for (i = pool->used; i < pool->size; i++) { | |
558 | e = ubi->lookuptbl[pool->pebs[i]]; | |
559 | wl_tree_add(e, &ubi->free); | |
560 | ubi->free_count++; | |
561 | } | |
562 | } | |
563 | ||
564 | /** | |
565 | * refill_wl_pool - refills all the fastmap pool used by the | |
566 | * WL sub-system. | |
567 | * @ubi: UBI device description object | |
568 | */ | |
569 | static void refill_wl_pool(struct ubi_device *ubi) | |
570 | { | |
571 | struct ubi_wl_entry *e; | |
572 | struct ubi_fm_pool *pool = &ubi->fm_wl_pool; | |
573 | ||
574 | return_unused_pool_pebs(ubi, pool); | |
575 | ||
576 | for (pool->size = 0; pool->size < pool->max_size; pool->size++) { | |
577 | if (!ubi->free.rb_node || | |
578 | (ubi->free_count - ubi->beb_rsvd_pebs < 5)) | |
579 | break; | |
580 | ||
581 | e = find_wl_entry(ubi, &ubi->free, WL_FREE_MAX_DIFF); | |
582 | self_check_in_wl_tree(ubi, e, &ubi->free); | |
583 | rb_erase(&e->u.rb, &ubi->free); | |
584 | ubi->free_count--; | |
585 | ||
586 | pool->pebs[pool->size] = e->pnum; | |
587 | } | |
588 | pool->used = 0; | |
589 | } | |
590 | ||
591 | /** | |
592 | * refill_wl_user_pool - refills all the fastmap pool used by ubi_wl_get_peb. | |
593 | * @ubi: UBI device description object | |
594 | */ | |
595 | static void refill_wl_user_pool(struct ubi_device *ubi) | |
596 | { | |
597 | struct ubi_fm_pool *pool = &ubi->fm_pool; | |
598 | ||
599 | return_unused_pool_pebs(ubi, pool); | |
600 | ||
601 | for (pool->size = 0; pool->size < pool->max_size; pool->size++) { | |
8199b901 RW |
602 | pool->pebs[pool->size] = __wl_get_peb(ubi); |
603 | if (pool->pebs[pool->size] < 0) | |
604 | break; | |
605 | } | |
606 | pool->used = 0; | |
607 | } | |
608 | ||
609 | /** | |
610 | * ubi_refill_pools - refills all fastmap PEB pools. | |
611 | * @ubi: UBI device description object | |
612 | */ | |
613 | void ubi_refill_pools(struct ubi_device *ubi) | |
614 | { | |
615 | spin_lock(&ubi->wl_lock); | |
616 | refill_wl_pool(ubi); | |
617 | refill_wl_user_pool(ubi); | |
618 | spin_unlock(&ubi->wl_lock); | |
619 | } | |
620 | ||
621 | /* ubi_wl_get_peb - works exaclty like __wl_get_peb but keeps track of | |
622 | * the fastmap pool. | |
623 | */ | |
624 | int ubi_wl_get_peb(struct ubi_device *ubi) | |
625 | { | |
626 | int ret; | |
627 | struct ubi_fm_pool *pool = &ubi->fm_pool; | |
628 | struct ubi_fm_pool *wl_pool = &ubi->fm_wl_pool; | |
629 | ||
630 | if (!pool->size || !wl_pool->size || pool->used == pool->size || | |
631 | wl_pool->used == wl_pool->size) | |
632 | ubi_update_fastmap(ubi); | |
633 | ||
634 | /* we got not a single free PEB */ | |
635 | if (!pool->size) | |
636 | ret = -ENOSPC; | |
637 | else { | |
638 | spin_lock(&ubi->wl_lock); | |
639 | ret = pool->pebs[pool->used++]; | |
640 | prot_queue_add(ubi, ubi->lookuptbl[ret]); | |
641 | spin_unlock(&ubi->wl_lock); | |
642 | } | |
643 | ||
644 | return ret; | |
645 | } | |
646 | ||
647 | /* get_peb_for_wl - returns a PEB to be used internally by the WL sub-system. | |
648 | * | |
649 | * @ubi: UBI device description object | |
650 | */ | |
651 | static struct ubi_wl_entry *get_peb_for_wl(struct ubi_device *ubi) | |
652 | { | |
653 | struct ubi_fm_pool *pool = &ubi->fm_wl_pool; | |
654 | int pnum; | |
655 | ||
656 | if (pool->used == pool->size || !pool->size) { | |
657 | /* We cannot update the fastmap here because this | |
658 | * function is called in atomic context. | |
659 | * Let's fail here and refill/update it as soon as possible. */ | |
660 | schedule_work(&ubi->fm_work); | |
661 | return NULL; | |
662 | } else { | |
663 | pnum = pool->pebs[pool->used++]; | |
664 | return ubi->lookuptbl[pnum]; | |
665 | } | |
666 | } | |
667 | #else | |
668 | static struct ubi_wl_entry *get_peb_for_wl(struct ubi_device *ubi) | |
669 | { | |
ed4b7021 RW |
670 | struct ubi_wl_entry *e; |
671 | ||
672 | e = find_wl_entry(ubi, &ubi->free, WL_FREE_MAX_DIFF); | |
673 | self_check_in_wl_tree(ubi, e, &ubi->free); | |
674 | rb_erase(&e->u.rb, &ubi->free); | |
675 | ||
676 | return e; | |
8199b901 RW |
677 | } |
678 | ||
679 | int ubi_wl_get_peb(struct ubi_device *ubi) | |
680 | { | |
894aef21 | 681 | int peb, err; |
8199b901 RW |
682 | |
683 | spin_lock(&ubi->wl_lock); | |
684 | peb = __wl_get_peb(ubi); | |
685 | spin_unlock(&ubi->wl_lock); | |
686 | ||
894aef21 RW |
687 | err = ubi_self_check_all_ff(ubi, peb, ubi->vid_hdr_aloffset, |
688 | ubi->peb_size - ubi->vid_hdr_aloffset); | |
689 | if (err) { | |
690 | ubi_err("new PEB %d does not contain all 0xFF bytes", peb); | |
691 | return err; | |
692 | } | |
693 | ||
8199b901 RW |
694 | return peb; |
695 | } | |
696 | #endif | |
697 | ||
801c135c | 698 | /** |
7b6c32da | 699 | * prot_queue_del - remove a physical eraseblock from the protection queue. |
801c135c AB |
700 | * @ubi: UBI device description object |
701 | * @pnum: the physical eraseblock to remove | |
43f9b25a | 702 | * |
7b6c32da XX |
703 | * This function deletes PEB @pnum from the protection queue and returns zero |
704 | * in case of success and %-ENODEV if the PEB was not found. | |
801c135c | 705 | */ |
7b6c32da | 706 | static int prot_queue_del(struct ubi_device *ubi, int pnum) |
801c135c | 707 | { |
7b6c32da | 708 | struct ubi_wl_entry *e; |
801c135c | 709 | |
7b6c32da XX |
710 | e = ubi->lookuptbl[pnum]; |
711 | if (!e) | |
712 | return -ENODEV; | |
801c135c | 713 | |
7bf523ae | 714 | if (self_check_in_pq(ubi, e)) |
7b6c32da | 715 | return -ENODEV; |
43f9b25a | 716 | |
7b6c32da XX |
717 | list_del(&e->u.list); |
718 | dbg_wl("deleted PEB %d from the protection queue", e->pnum); | |
43f9b25a | 719 | return 0; |
801c135c AB |
720 | } |
721 | ||
722 | /** | |
723 | * sync_erase - synchronously erase a physical eraseblock. | |
724 | * @ubi: UBI device description object | |
725 | * @e: the the physical eraseblock to erase | |
726 | * @torture: if the physical eraseblock has to be tortured | |
727 | * | |
728 | * This function returns zero in case of success and a negative error code in | |
729 | * case of failure. | |
730 | */ | |
9c9ec147 AB |
731 | static int sync_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, |
732 | int torture) | |
801c135c AB |
733 | { |
734 | int err; | |
735 | struct ubi_ec_hdr *ec_hdr; | |
736 | unsigned long long ec = e->ec; | |
737 | ||
738 | dbg_wl("erase PEB %d, old EC %llu", e->pnum, ec); | |
739 | ||
7bf523ae | 740 | err = self_check_ec(ubi, e->pnum, e->ec); |
adbf05e3 | 741 | if (err) |
801c135c AB |
742 | return -EINVAL; |
743 | ||
33818bbb | 744 | ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_NOFS); |
801c135c AB |
745 | if (!ec_hdr) |
746 | return -ENOMEM; | |
747 | ||
748 | err = ubi_io_sync_erase(ubi, e->pnum, torture); | |
749 | if (err < 0) | |
750 | goto out_free; | |
751 | ||
752 | ec += err; | |
753 | if (ec > UBI_MAX_ERASECOUNTER) { | |
754 | /* | |
755 | * Erase counter overflow. Upgrade UBI and use 64-bit | |
756 | * erase counters internally. | |
757 | */ | |
758 | ubi_err("erase counter overflow at PEB %d, EC %llu", | |
759 | e->pnum, ec); | |
760 | err = -EINVAL; | |
761 | goto out_free; | |
762 | } | |
763 | ||
764 | dbg_wl("erased PEB %d, new EC %llu", e->pnum, ec); | |
765 | ||
3261ebd7 | 766 | ec_hdr->ec = cpu_to_be64(ec); |
801c135c AB |
767 | |
768 | err = ubi_io_write_ec_hdr(ubi, e->pnum, ec_hdr); | |
769 | if (err) | |
770 | goto out_free; | |
771 | ||
772 | e->ec = ec; | |
773 | spin_lock(&ubi->wl_lock); | |
774 | if (e->ec > ubi->max_ec) | |
775 | ubi->max_ec = e->ec; | |
776 | spin_unlock(&ubi->wl_lock); | |
777 | ||
778 | out_free: | |
779 | kfree(ec_hdr); | |
780 | return err; | |
781 | } | |
782 | ||
783 | /** | |
7b6c32da | 784 | * serve_prot_queue - check if it is time to stop protecting PEBs. |
801c135c AB |
785 | * @ubi: UBI device description object |
786 | * | |
7b6c32da XX |
787 | * This function is called after each erase operation and removes PEBs from the |
788 | * tail of the protection queue. These PEBs have been protected for long enough | |
789 | * and should be moved to the used tree. | |
801c135c | 790 | */ |
7b6c32da | 791 | static void serve_prot_queue(struct ubi_device *ubi) |
801c135c | 792 | { |
7b6c32da XX |
793 | struct ubi_wl_entry *e, *tmp; |
794 | int count; | |
801c135c AB |
795 | |
796 | /* | |
797 | * There may be several protected physical eraseblock to remove, | |
798 | * process them all. | |
799 | */ | |
7b6c32da XX |
800 | repeat: |
801 | count = 0; | |
802 | spin_lock(&ubi->wl_lock); | |
803 | list_for_each_entry_safe(e, tmp, &ubi->pq[ubi->pq_head], u.list) { | |
804 | dbg_wl("PEB %d EC %d protection over, move to used tree", | |
805 | e->pnum, e->ec); | |
801c135c | 806 | |
7b6c32da XX |
807 | list_del(&e->u.list); |
808 | wl_tree_add(e, &ubi->used); | |
809 | if (count++ > 32) { | |
810 | /* | |
811 | * Let's be nice and avoid holding the spinlock for | |
812 | * too long. | |
813 | */ | |
801c135c | 814 | spin_unlock(&ubi->wl_lock); |
7b6c32da XX |
815 | cond_resched(); |
816 | goto repeat; | |
801c135c | 817 | } |
801c135c | 818 | } |
7b6c32da XX |
819 | |
820 | ubi->pq_head += 1; | |
821 | if (ubi->pq_head == UBI_PROT_QUEUE_LEN) | |
822 | ubi->pq_head = 0; | |
823 | ubi_assert(ubi->pq_head >= 0 && ubi->pq_head < UBI_PROT_QUEUE_LEN); | |
824 | spin_unlock(&ubi->wl_lock); | |
801c135c AB |
825 | } |
826 | ||
827 | /** | |
8199b901 | 828 | * __schedule_ubi_work - schedule a work. |
801c135c AB |
829 | * @ubi: UBI device description object |
830 | * @wrk: the work to schedule | |
831 | * | |
7b6c32da | 832 | * This function adds a work defined by @wrk to the tail of the pending works |
8199b901 | 833 | * list. Can only be used of ubi->work_sem is already held in read mode! |
801c135c | 834 | */ |
8199b901 | 835 | static void __schedule_ubi_work(struct ubi_device *ubi, struct ubi_work *wrk) |
801c135c AB |
836 | { |
837 | spin_lock(&ubi->wl_lock); | |
838 | list_add_tail(&wrk->list, &ubi->works); | |
839 | ubi_assert(ubi->works_count >= 0); | |
840 | ubi->works_count += 1; | |
27a0f2a3 | 841 | if (ubi->thread_enabled && !ubi_dbg_is_bgt_disabled(ubi)) |
801c135c AB |
842 | wake_up_process(ubi->bgt_thread); |
843 | spin_unlock(&ubi->wl_lock); | |
844 | } | |
845 | ||
8199b901 RW |
846 | /** |
847 | * schedule_ubi_work - schedule a work. | |
848 | * @ubi: UBI device description object | |
849 | * @wrk: the work to schedule | |
850 | * | |
851 | * This function adds a work defined by @wrk to the tail of the pending works | |
852 | * list. | |
853 | */ | |
854 | static void schedule_ubi_work(struct ubi_device *ubi, struct ubi_work *wrk) | |
855 | { | |
856 | down_read(&ubi->work_sem); | |
857 | __schedule_ubi_work(ubi, wrk); | |
858 | up_read(&ubi->work_sem); | |
859 | } | |
860 | ||
801c135c AB |
861 | static int erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk, |
862 | int cancel); | |
863 | ||
8199b901 RW |
864 | #ifdef CONFIG_MTD_UBI_FASTMAP |
865 | /** | |
866 | * ubi_is_erase_work - checks whether a work is erase work. | |
867 | * @wrk: The work object to be checked | |
868 | */ | |
869 | int ubi_is_erase_work(struct ubi_work *wrk) | |
870 | { | |
871 | return wrk->func == erase_worker; | |
872 | } | |
873 | #endif | |
874 | ||
801c135c AB |
875 | /** |
876 | * schedule_erase - schedule an erase work. | |
877 | * @ubi: UBI device description object | |
878 | * @e: the WL entry of the physical eraseblock to erase | |
d36e59e6 JR |
879 | * @vol_id: the volume ID that last used this PEB |
880 | * @lnum: the last used logical eraseblock number for the PEB | |
801c135c AB |
881 | * @torture: if the physical eraseblock has to be tortured |
882 | * | |
883 | * This function returns zero in case of success and a %-ENOMEM in case of | |
884 | * failure. | |
885 | */ | |
886 | static int schedule_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, | |
d36e59e6 | 887 | int vol_id, int lnum, int torture) |
801c135c AB |
888 | { |
889 | struct ubi_work *wl_wrk; | |
890 | ||
8199b901 RW |
891 | ubi_assert(e); |
892 | ubi_assert(!ubi_is_fm_block(ubi, e->pnum)); | |
893 | ||
801c135c AB |
894 | dbg_wl("schedule erasure of PEB %d, EC %d, torture %d", |
895 | e->pnum, e->ec, torture); | |
896 | ||
33818bbb | 897 | wl_wrk = kmalloc(sizeof(struct ubi_work), GFP_NOFS); |
801c135c AB |
898 | if (!wl_wrk) |
899 | return -ENOMEM; | |
900 | ||
901 | wl_wrk->func = &erase_worker; | |
902 | wl_wrk->e = e; | |
d36e59e6 JR |
903 | wl_wrk->vol_id = vol_id; |
904 | wl_wrk->lnum = lnum; | |
801c135c AB |
905 | wl_wrk->torture = torture; |
906 | ||
907 | schedule_ubi_work(ubi, wl_wrk); | |
908 | return 0; | |
909 | } | |
910 | ||
8199b901 RW |
911 | /** |
912 | * do_sync_erase - run the erase worker synchronously. | |
913 | * @ubi: UBI device description object | |
914 | * @e: the WL entry of the physical eraseblock to erase | |
915 | * @vol_id: the volume ID that last used this PEB | |
916 | * @lnum: the last used logical eraseblock number for the PEB | |
917 | * @torture: if the physical eraseblock has to be tortured | |
918 | * | |
919 | */ | |
920 | static int do_sync_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, | |
921 | int vol_id, int lnum, int torture) | |
922 | { | |
923 | struct ubi_work *wl_wrk; | |
924 | ||
925 | dbg_wl("sync erase of PEB %i", e->pnum); | |
926 | ||
927 | wl_wrk = kmalloc(sizeof(struct ubi_work), GFP_NOFS); | |
928 | if (!wl_wrk) | |
929 | return -ENOMEM; | |
930 | ||
931 | wl_wrk->e = e; | |
932 | wl_wrk->vol_id = vol_id; | |
933 | wl_wrk->lnum = lnum; | |
934 | wl_wrk->torture = torture; | |
935 | ||
936 | return erase_worker(ubi, wl_wrk, 0); | |
937 | } | |
938 | ||
939 | #ifdef CONFIG_MTD_UBI_FASTMAP | |
940 | /** | |
941 | * ubi_wl_put_fm_peb - returns a PEB used in a fastmap to the wear-leveling | |
942 | * sub-system. | |
943 | * see: ubi_wl_put_peb() | |
944 | * | |
945 | * @ubi: UBI device description object | |
946 | * @fm_e: physical eraseblock to return | |
947 | * @lnum: the last used logical eraseblock number for the PEB | |
948 | * @torture: if this physical eraseblock has to be tortured | |
949 | */ | |
950 | int ubi_wl_put_fm_peb(struct ubi_device *ubi, struct ubi_wl_entry *fm_e, | |
951 | int lnum, int torture) | |
952 | { | |
953 | struct ubi_wl_entry *e; | |
954 | int vol_id, pnum = fm_e->pnum; | |
955 | ||
956 | dbg_wl("PEB %d", pnum); | |
957 | ||
958 | ubi_assert(pnum >= 0); | |
959 | ubi_assert(pnum < ubi->peb_count); | |
960 | ||
961 | spin_lock(&ubi->wl_lock); | |
962 | e = ubi->lookuptbl[pnum]; | |
963 | ||
964 | /* This can happen if we recovered from a fastmap the very | |
965 | * first time and writing now a new one. In this case the wl system | |
966 | * has never seen any PEB used by the original fastmap. | |
967 | */ | |
968 | if (!e) { | |
969 | e = fm_e; | |
970 | ubi_assert(e->ec >= 0); | |
971 | ubi->lookuptbl[pnum] = e; | |
972 | } else { | |
973 | e->ec = fm_e->ec; | |
974 | kfree(fm_e); | |
975 | } | |
976 | ||
977 | spin_unlock(&ubi->wl_lock); | |
978 | ||
979 | vol_id = lnum ? UBI_FM_DATA_VOLUME_ID : UBI_FM_SB_VOLUME_ID; | |
980 | return schedule_erase(ubi, e, vol_id, lnum, torture); | |
981 | } | |
982 | #endif | |
983 | ||
801c135c AB |
984 | /** |
985 | * wear_leveling_worker - wear-leveling worker function. | |
986 | * @ubi: UBI device description object | |
987 | * @wrk: the work object | |
988 | * @cancel: non-zero if the worker has to free memory and exit | |
989 | * | |
990 | * This function copies a more worn out physical eraseblock to a less worn out | |
991 | * one. Returns zero in case of success and a negative error code in case of | |
992 | * failure. | |
993 | */ | |
994 | static int wear_leveling_worker(struct ubi_device *ubi, struct ubi_work *wrk, | |
995 | int cancel) | |
996 | { | |
b86a2c56 | 997 | int err, scrubbing = 0, torture = 0, protect = 0, erroneous = 0; |
9c259a52 | 998 | int vol_id = -1, uninitialized_var(lnum); |
8199b901 RW |
999 | #ifdef CONFIG_MTD_UBI_FASTMAP |
1000 | int anchor = wrk->anchor; | |
1001 | #endif | |
801c135c AB |
1002 | struct ubi_wl_entry *e1, *e2; |
1003 | struct ubi_vid_hdr *vid_hdr; | |
1004 | ||
1005 | kfree(wrk); | |
801c135c AB |
1006 | if (cancel) |
1007 | return 0; | |
1008 | ||
33818bbb | 1009 | vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS); |
801c135c AB |
1010 | if (!vid_hdr) |
1011 | return -ENOMEM; | |
1012 | ||
43f9b25a | 1013 | mutex_lock(&ubi->move_mutex); |
801c135c | 1014 | spin_lock(&ubi->wl_lock); |
43f9b25a AB |
1015 | ubi_assert(!ubi->move_from && !ubi->move_to); |
1016 | ubi_assert(!ubi->move_to_put); | |
801c135c | 1017 | |
43f9b25a | 1018 | if (!ubi->free.rb_node || |
5abde384 | 1019 | (!ubi->used.rb_node && !ubi->scrub.rb_node)) { |
801c135c | 1020 | /* |
43f9b25a AB |
1021 | * No free physical eraseblocks? Well, they must be waiting in |
1022 | * the queue to be erased. Cancel movement - it will be | |
1023 | * triggered again when a free physical eraseblock appears. | |
801c135c AB |
1024 | * |
1025 | * No used physical eraseblocks? They must be temporarily | |
1026 | * protected from being moved. They will be moved to the | |
1027 | * @ubi->used tree later and the wear-leveling will be | |
1028 | * triggered again. | |
1029 | */ | |
1030 | dbg_wl("cancel WL, a list is empty: free %d, used %d", | |
5abde384 | 1031 | !ubi->free.rb_node, !ubi->used.rb_node); |
43f9b25a | 1032 | goto out_cancel; |
801c135c AB |
1033 | } |
1034 | ||
8199b901 RW |
1035 | #ifdef CONFIG_MTD_UBI_FASTMAP |
1036 | /* Check whether we need to produce an anchor PEB */ | |
1037 | if (!anchor) | |
1038 | anchor = !anchor_pebs_avalible(&ubi->free); | |
1039 | ||
1040 | if (anchor) { | |
1041 | e1 = find_anchor_wl_entry(&ubi->used); | |
1042 | if (!e1) | |
1043 | goto out_cancel; | |
1044 | e2 = get_peb_for_wl(ubi); | |
1045 | if (!e2) | |
1046 | goto out_cancel; | |
1047 | ||
1048 | self_check_in_wl_tree(ubi, e1, &ubi->used); | |
1049 | rb_erase(&e1->u.rb, &ubi->used); | |
1050 | dbg_wl("anchor-move PEB %d to PEB %d", e1->pnum, e2->pnum); | |
1051 | } else if (!ubi->scrub.rb_node) { | |
1052 | #else | |
5abde384 | 1053 | if (!ubi->scrub.rb_node) { |
8199b901 | 1054 | #endif |
801c135c AB |
1055 | /* |
1056 | * Now pick the least worn-out used physical eraseblock and a | |
1057 | * highly worn-out free physical eraseblock. If the erase | |
1058 | * counters differ much enough, start wear-leveling. | |
1059 | */ | |
23553b2c | 1060 | e1 = rb_entry(rb_first(&ubi->used), struct ubi_wl_entry, u.rb); |
8199b901 RW |
1061 | e2 = get_peb_for_wl(ubi); |
1062 | if (!e2) | |
1063 | goto out_cancel; | |
801c135c AB |
1064 | |
1065 | if (!(e2->ec - e1->ec >= UBI_WL_THRESHOLD)) { | |
1066 | dbg_wl("no WL needed: min used EC %d, max free EC %d", | |
1067 | e1->ec, e2->ec); | |
5ef4414f RW |
1068 | |
1069 | /* Give the unused PEB back */ | |
1070 | wl_tree_add(e2, &ubi->free); | |
43f9b25a | 1071 | goto out_cancel; |
801c135c | 1072 | } |
7bf523ae | 1073 | self_check_in_wl_tree(ubi, e1, &ubi->used); |
23553b2c | 1074 | rb_erase(&e1->u.rb, &ubi->used); |
801c135c AB |
1075 | dbg_wl("move PEB %d EC %d to PEB %d EC %d", |
1076 | e1->pnum, e1->ec, e2->pnum, e2->ec); | |
1077 | } else { | |
43f9b25a AB |
1078 | /* Perform scrubbing */ |
1079 | scrubbing = 1; | |
23553b2c | 1080 | e1 = rb_entry(rb_first(&ubi->scrub), struct ubi_wl_entry, u.rb); |
8199b901 RW |
1081 | e2 = get_peb_for_wl(ubi); |
1082 | if (!e2) | |
1083 | goto out_cancel; | |
1084 | ||
7bf523ae | 1085 | self_check_in_wl_tree(ubi, e1, &ubi->scrub); |
23553b2c | 1086 | rb_erase(&e1->u.rb, &ubi->scrub); |
801c135c AB |
1087 | dbg_wl("scrub PEB %d to PEB %d", e1->pnum, e2->pnum); |
1088 | } | |
1089 | ||
801c135c AB |
1090 | ubi->move_from = e1; |
1091 | ubi->move_to = e2; | |
1092 | spin_unlock(&ubi->wl_lock); | |
1093 | ||
1094 | /* | |
1095 | * Now we are going to copy physical eraseblock @e1->pnum to @e2->pnum. | |
1096 | * We so far do not know which logical eraseblock our physical | |
1097 | * eraseblock (@e1) belongs to. We have to read the volume identifier | |
1098 | * header first. | |
43f9b25a AB |
1099 | * |
1100 | * Note, we are protected from this PEB being unmapped and erased. The | |
1101 | * 'ubi_wl_put_peb()' would wait for moving to be finished if the PEB | |
1102 | * which is being moved was unmapped. | |
801c135c AB |
1103 | */ |
1104 | ||
1105 | err = ubi_io_read_vid_hdr(ubi, e1->pnum, vid_hdr, 0); | |
1106 | if (err && err != UBI_IO_BITFLIPS) { | |
74d82d26 | 1107 | if (err == UBI_IO_FF) { |
801c135c AB |
1108 | /* |
1109 | * We are trying to move PEB without a VID header. UBI | |
1110 | * always write VID headers shortly after the PEB was | |
87960c0b AB |
1111 | * given, so we have a situation when it has not yet |
1112 | * had a chance to write it, because it was preempted. | |
1113 | * So add this PEB to the protection queue so far, | |
815bc5f8 AB |
1114 | * because presumably more data will be written there |
1115 | * (including the missing VID header), and then we'll | |
87960c0b | 1116 | * move it. |
801c135c AB |
1117 | */ |
1118 | dbg_wl("PEB %d has no VID header", e1->pnum); | |
87960c0b | 1119 | protect = 1; |
43f9b25a | 1120 | goto out_not_moved; |
92e1a7d9 AB |
1121 | } else if (err == UBI_IO_FF_BITFLIPS) { |
1122 | /* | |
1123 | * The same situation as %UBI_IO_FF, but bit-flips were | |
1124 | * detected. It is better to schedule this PEB for | |
1125 | * scrubbing. | |
1126 | */ | |
1127 | dbg_wl("PEB %d has no VID header but has bit-flips", | |
1128 | e1->pnum); | |
1129 | scrubbing = 1; | |
1130 | goto out_not_moved; | |
801c135c | 1131 | } |
43f9b25a AB |
1132 | |
1133 | ubi_err("error %d while reading VID header from PEB %d", | |
1134 | err, e1->pnum); | |
43f9b25a | 1135 | goto out_error; |
801c135c AB |
1136 | } |
1137 | ||
9c259a52 AB |
1138 | vol_id = be32_to_cpu(vid_hdr->vol_id); |
1139 | lnum = be32_to_cpu(vid_hdr->lnum); | |
1140 | ||
801c135c AB |
1141 | err = ubi_eba_copy_leb(ubi, e1->pnum, e2->pnum, vid_hdr); |
1142 | if (err) { | |
87960c0b AB |
1143 | if (err == MOVE_CANCEL_RACE) { |
1144 | /* | |
1145 | * The LEB has not been moved because the volume is | |
1146 | * being deleted or the PEB has been put meanwhile. We | |
1147 | * should prevent this PEB from being selected for | |
1148 | * wear-leveling movement again, so put it to the | |
1149 | * protection queue. | |
1150 | */ | |
1151 | protect = 1; | |
1152 | goto out_not_moved; | |
1153 | } | |
e801e128 BP |
1154 | if (err == MOVE_RETRY) { |
1155 | scrubbing = 1; | |
1156 | goto out_not_moved; | |
1157 | } | |
cc831464 | 1158 | if (err == MOVE_TARGET_BITFLIPS || err == MOVE_TARGET_WR_ERR || |
b86a2c56 | 1159 | err == MOVE_TARGET_RD_ERR) { |
9c259a52 AB |
1160 | /* |
1161 | * Target PEB had bit-flips or write error - torture it. | |
1162 | */ | |
6fa6f5bb | 1163 | torture = 1; |
43f9b25a | 1164 | goto out_not_moved; |
6fa6f5bb | 1165 | } |
87960c0b | 1166 | |
b86a2c56 AB |
1167 | if (err == MOVE_SOURCE_RD_ERR) { |
1168 | /* | |
1169 | * An error happened while reading the source PEB. Do | |
1170 | * not switch to R/O mode in this case, and give the | |
1171 | * upper layers a possibility to recover from this, | |
1172 | * e.g. by unmapping corresponding LEB. Instead, just | |
815bc5f8 AB |
1173 | * put this PEB to the @ubi->erroneous list to prevent |
1174 | * UBI from trying to move it over and over again. | |
b86a2c56 AB |
1175 | */ |
1176 | if (ubi->erroneous_peb_count > ubi->max_erroneous) { | |
1177 | ubi_err("too many erroneous eraseblocks (%d)", | |
1178 | ubi->erroneous_peb_count); | |
1179 | goto out_error; | |
1180 | } | |
1181 | erroneous = 1; | |
1182 | goto out_not_moved; | |
1183 | } | |
1184 | ||
90bf0265 AB |
1185 | if (err < 0) |
1186 | goto out_error; | |
43f9b25a | 1187 | |
87960c0b | 1188 | ubi_assert(0); |
801c135c AB |
1189 | } |
1190 | ||
6a8f483f | 1191 | /* The PEB has been successfully moved */ |
6a8f483f | 1192 | if (scrubbing) |
9c259a52 AB |
1193 | ubi_msg("scrubbed PEB %d (LEB %d:%d), data moved to PEB %d", |
1194 | e1->pnum, vol_id, lnum, e2->pnum); | |
1195 | ubi_free_vid_hdr(ubi, vid_hdr); | |
8c1e6ee1 | 1196 | |
801c135c | 1197 | spin_lock(&ubi->wl_lock); |
3c98b0a0 | 1198 | if (!ubi->move_to_put) { |
5abde384 | 1199 | wl_tree_add(e2, &ubi->used); |
3c98b0a0 AB |
1200 | e2 = NULL; |
1201 | } | |
801c135c | 1202 | ubi->move_from = ubi->move_to = NULL; |
43f9b25a | 1203 | ubi->move_to_put = ubi->wl_scheduled = 0; |
801c135c AB |
1204 | spin_unlock(&ubi->wl_lock); |
1205 | ||
8199b901 | 1206 | err = do_sync_erase(ubi, e1, vol_id, lnum, 0); |
3c98b0a0 | 1207 | if (err) { |
87960c0b | 1208 | kmem_cache_free(ubi_wl_entry_slab, e1); |
21d08bbc AB |
1209 | if (e2) |
1210 | kmem_cache_free(ubi_wl_entry_slab, e2); | |
87960c0b | 1211 | goto out_ro; |
3c98b0a0 | 1212 | } |
6a8f483f | 1213 | |
3c98b0a0 | 1214 | if (e2) { |
801c135c AB |
1215 | /* |
1216 | * Well, the target PEB was put meanwhile, schedule it for | |
1217 | * erasure. | |
1218 | */ | |
9c259a52 AB |
1219 | dbg_wl("PEB %d (LEB %d:%d) was put meanwhile, erase", |
1220 | e2->pnum, vol_id, lnum); | |
8199b901 | 1221 | err = do_sync_erase(ubi, e2, vol_id, lnum, 0); |
87960c0b AB |
1222 | if (err) { |
1223 | kmem_cache_free(ubi_wl_entry_slab, e2); | |
1224 | goto out_ro; | |
1225 | } | |
801c135c AB |
1226 | } |
1227 | ||
801c135c | 1228 | dbg_wl("done"); |
43f9b25a AB |
1229 | mutex_unlock(&ubi->move_mutex); |
1230 | return 0; | |
801c135c AB |
1231 | |
1232 | /* | |
43f9b25a AB |
1233 | * For some reasons the LEB was not moved, might be an error, might be |
1234 | * something else. @e1 was not changed, so return it back. @e2 might | |
6fa6f5bb | 1235 | * have been changed, schedule it for erasure. |
801c135c | 1236 | */ |
43f9b25a | 1237 | out_not_moved: |
9c259a52 AB |
1238 | if (vol_id != -1) |
1239 | dbg_wl("cancel moving PEB %d (LEB %d:%d) to PEB %d (%d)", | |
1240 | e1->pnum, vol_id, lnum, e2->pnum, err); | |
1241 | else | |
1242 | dbg_wl("cancel moving PEB %d to PEB %d (%d)", | |
1243 | e1->pnum, e2->pnum, err); | |
801c135c | 1244 | spin_lock(&ubi->wl_lock); |
87960c0b AB |
1245 | if (protect) |
1246 | prot_queue_add(ubi, e1); | |
b86a2c56 AB |
1247 | else if (erroneous) { |
1248 | wl_tree_add(e1, &ubi->erroneous); | |
1249 | ubi->erroneous_peb_count += 1; | |
1250 | } else if (scrubbing) | |
43f9b25a | 1251 | wl_tree_add(e1, &ubi->scrub); |
801c135c | 1252 | else |
5abde384 | 1253 | wl_tree_add(e1, &ubi->used); |
6fa6f5bb | 1254 | ubi_assert(!ubi->move_to_put); |
801c135c | 1255 | ubi->move_from = ubi->move_to = NULL; |
6fa6f5bb | 1256 | ubi->wl_scheduled = 0; |
801c135c AB |
1257 | spin_unlock(&ubi->wl_lock); |
1258 | ||
87960c0b | 1259 | ubi_free_vid_hdr(ubi, vid_hdr); |
8199b901 | 1260 | err = do_sync_erase(ubi, e2, vol_id, lnum, torture); |
87960c0b AB |
1261 | if (err) { |
1262 | kmem_cache_free(ubi_wl_entry_slab, e2); | |
1263 | goto out_ro; | |
1264 | } | |
43f9b25a AB |
1265 | mutex_unlock(&ubi->move_mutex); |
1266 | return 0; | |
1267 | ||
1268 | out_error: | |
9c259a52 AB |
1269 | if (vol_id != -1) |
1270 | ubi_err("error %d while moving PEB %d to PEB %d", | |
1271 | err, e1->pnum, e2->pnum); | |
1272 | else | |
1273 | ubi_err("error %d while moving PEB %d (LEB %d:%d) to PEB %d", | |
1274 | err, e1->pnum, vol_id, lnum, e2->pnum); | |
43f9b25a AB |
1275 | spin_lock(&ubi->wl_lock); |
1276 | ubi->move_from = ubi->move_to = NULL; | |
1277 | ubi->move_to_put = ubi->wl_scheduled = 0; | |
1278 | spin_unlock(&ubi->wl_lock); | |
1279 | ||
87960c0b AB |
1280 | ubi_free_vid_hdr(ubi, vid_hdr); |
1281 | kmem_cache_free(ubi_wl_entry_slab, e1); | |
1282 | kmem_cache_free(ubi_wl_entry_slab, e2); | |
43f9b25a | 1283 | |
87960c0b AB |
1284 | out_ro: |
1285 | ubi_ro_mode(ubi); | |
43f9b25a | 1286 | mutex_unlock(&ubi->move_mutex); |
87960c0b AB |
1287 | ubi_assert(err != 0); |
1288 | return err < 0 ? err : -EIO; | |
43f9b25a AB |
1289 | |
1290 | out_cancel: | |
1291 | ubi->wl_scheduled = 0; | |
1292 | spin_unlock(&ubi->wl_lock); | |
1293 | mutex_unlock(&ubi->move_mutex); | |
1294 | ubi_free_vid_hdr(ubi, vid_hdr); | |
1295 | return 0; | |
801c135c AB |
1296 | } |
1297 | ||
1298 | /** | |
1299 | * ensure_wear_leveling - schedule wear-leveling if it is needed. | |
1300 | * @ubi: UBI device description object | |
8199b901 | 1301 | * @nested: set to non-zero if this function is called from UBI worker |
801c135c AB |
1302 | * |
1303 | * This function checks if it is time to start wear-leveling and schedules it | |
1304 | * if yes. This function returns zero in case of success and a negative error | |
1305 | * code in case of failure. | |
1306 | */ | |
8199b901 | 1307 | static int ensure_wear_leveling(struct ubi_device *ubi, int nested) |
801c135c AB |
1308 | { |
1309 | int err = 0; | |
1310 | struct ubi_wl_entry *e1; | |
1311 | struct ubi_wl_entry *e2; | |
1312 | struct ubi_work *wrk; | |
1313 | ||
1314 | spin_lock(&ubi->wl_lock); | |
1315 | if (ubi->wl_scheduled) | |
1316 | /* Wear-leveling is already in the work queue */ | |
1317 | goto out_unlock; | |
1318 | ||
1319 | /* | |
1320 | * If the ubi->scrub tree is not empty, scrubbing is needed, and the | |
1321 | * the WL worker has to be scheduled anyway. | |
1322 | */ | |
5abde384 AB |
1323 | if (!ubi->scrub.rb_node) { |
1324 | if (!ubi->used.rb_node || !ubi->free.rb_node) | |
801c135c AB |
1325 | /* No physical eraseblocks - no deal */ |
1326 | goto out_unlock; | |
1327 | ||
1328 | /* | |
1329 | * We schedule wear-leveling only if the difference between the | |
1330 | * lowest erase counter of used physical eraseblocks and a high | |
025dfdaf | 1331 | * erase counter of free physical eraseblocks is greater than |
801c135c AB |
1332 | * %UBI_WL_THRESHOLD. |
1333 | */ | |
23553b2c | 1334 | e1 = rb_entry(rb_first(&ubi->used), struct ubi_wl_entry, u.rb); |
8199b901 | 1335 | e2 = find_wl_entry(ubi, &ubi->free, WL_FREE_MAX_DIFF); |
801c135c AB |
1336 | |
1337 | if (!(e2->ec - e1->ec >= UBI_WL_THRESHOLD)) | |
1338 | goto out_unlock; | |
1339 | dbg_wl("schedule wear-leveling"); | |
1340 | } else | |
1341 | dbg_wl("schedule scrubbing"); | |
1342 | ||
1343 | ubi->wl_scheduled = 1; | |
1344 | spin_unlock(&ubi->wl_lock); | |
1345 | ||
33818bbb | 1346 | wrk = kmalloc(sizeof(struct ubi_work), GFP_NOFS); |
801c135c AB |
1347 | if (!wrk) { |
1348 | err = -ENOMEM; | |
1349 | goto out_cancel; | |
1350 | } | |
1351 | ||
8199b901 | 1352 | wrk->anchor = 0; |
801c135c | 1353 | wrk->func = &wear_leveling_worker; |
8199b901 RW |
1354 | if (nested) |
1355 | __schedule_ubi_work(ubi, wrk); | |
1356 | else | |
1357 | schedule_ubi_work(ubi, wrk); | |
801c135c AB |
1358 | return err; |
1359 | ||
1360 | out_cancel: | |
1361 | spin_lock(&ubi->wl_lock); | |
1362 | ubi->wl_scheduled = 0; | |
1363 | out_unlock: | |
1364 | spin_unlock(&ubi->wl_lock); | |
1365 | return err; | |
1366 | } | |
1367 | ||
8199b901 RW |
1368 | #ifdef CONFIG_MTD_UBI_FASTMAP |
1369 | /** | |
1370 | * ubi_ensure_anchor_pebs - schedule wear-leveling to produce an anchor PEB. | |
1371 | * @ubi: UBI device description object | |
1372 | */ | |
1373 | int ubi_ensure_anchor_pebs(struct ubi_device *ubi) | |
1374 | { | |
1375 | struct ubi_work *wrk; | |
1376 | ||
1377 | spin_lock(&ubi->wl_lock); | |
1378 | if (ubi->wl_scheduled) { | |
1379 | spin_unlock(&ubi->wl_lock); | |
1380 | return 0; | |
1381 | } | |
1382 | ubi->wl_scheduled = 1; | |
1383 | spin_unlock(&ubi->wl_lock); | |
1384 | ||
1385 | wrk = kmalloc(sizeof(struct ubi_work), GFP_NOFS); | |
1386 | if (!wrk) { | |
1387 | spin_lock(&ubi->wl_lock); | |
1388 | ubi->wl_scheduled = 0; | |
1389 | spin_unlock(&ubi->wl_lock); | |
1390 | return -ENOMEM; | |
1391 | } | |
1392 | ||
1393 | wrk->anchor = 1; | |
1394 | wrk->func = &wear_leveling_worker; | |
1395 | schedule_ubi_work(ubi, wrk); | |
1396 | return 0; | |
1397 | } | |
1398 | #endif | |
1399 | ||
801c135c AB |
1400 | /** |
1401 | * erase_worker - physical eraseblock erase worker function. | |
1402 | * @ubi: UBI device description object | |
1403 | * @wl_wrk: the work object | |
1404 | * @cancel: non-zero if the worker has to free memory and exit | |
1405 | * | |
1406 | * This function erases a physical eraseblock and perform torture testing if | |
1407 | * needed. It also takes care about marking the physical eraseblock bad if | |
1408 | * needed. Returns zero in case of success and a negative error code in case of | |
1409 | * failure. | |
1410 | */ | |
1411 | static int erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk, | |
1412 | int cancel) | |
1413 | { | |
801c135c | 1414 | struct ubi_wl_entry *e = wl_wrk->e; |
37f758a0 | 1415 | int pnum = e->pnum; |
d36e59e6 JR |
1416 | int vol_id = wl_wrk->vol_id; |
1417 | int lnum = wl_wrk->lnum; | |
37f758a0 | 1418 | int err, available_consumed = 0; |
801c135c AB |
1419 | |
1420 | if (cancel) { | |
1421 | dbg_wl("cancel erasure of PEB %d EC %d", pnum, e->ec); | |
1422 | kfree(wl_wrk); | |
06b68ba1 | 1423 | kmem_cache_free(ubi_wl_entry_slab, e); |
801c135c AB |
1424 | return 0; |
1425 | } | |
1426 | ||
d36e59e6 JR |
1427 | dbg_wl("erase PEB %d EC %d LEB %d:%d", |
1428 | pnum, e->ec, wl_wrk->vol_id, wl_wrk->lnum); | |
801c135c | 1429 | |
8199b901 RW |
1430 | ubi_assert(!ubi_is_fm_block(ubi, e->pnum)); |
1431 | ||
801c135c AB |
1432 | err = sync_erase(ubi, e, wl_wrk->torture); |
1433 | if (!err) { | |
1434 | /* Fine, we've erased it successfully */ | |
1435 | kfree(wl_wrk); | |
1436 | ||
1437 | spin_lock(&ubi->wl_lock); | |
5abde384 | 1438 | wl_tree_add(e, &ubi->free); |
8199b901 | 1439 | ubi->free_count++; |
801c135c AB |
1440 | spin_unlock(&ubi->wl_lock); |
1441 | ||
1442 | /* | |
9c9ec147 AB |
1443 | * One more erase operation has happened, take care about |
1444 | * protected physical eraseblocks. | |
801c135c | 1445 | */ |
7b6c32da | 1446 | serve_prot_queue(ubi); |
801c135c AB |
1447 | |
1448 | /* And take care about wear-leveling */ | |
8199b901 | 1449 | err = ensure_wear_leveling(ubi, 1); |
801c135c AB |
1450 | return err; |
1451 | } | |
1452 | ||
8d2d4011 | 1453 | ubi_err("failed to erase PEB %d, error %d", pnum, err); |
801c135c | 1454 | kfree(wl_wrk); |
801c135c | 1455 | |
784c1454 AB |
1456 | if (err == -EINTR || err == -ENOMEM || err == -EAGAIN || |
1457 | err == -EBUSY) { | |
1458 | int err1; | |
1459 | ||
1460 | /* Re-schedule the LEB for erasure */ | |
d36e59e6 | 1461 | err1 = schedule_erase(ubi, e, vol_id, lnum, 0); |
784c1454 AB |
1462 | if (err1) { |
1463 | err = err1; | |
1464 | goto out_ro; | |
1465 | } | |
1466 | return err; | |
e57e0d8e AB |
1467 | } |
1468 | ||
1469 | kmem_cache_free(ubi_wl_entry_slab, e); | |
1470 | if (err != -EIO) | |
801c135c AB |
1471 | /* |
1472 | * If this is not %-EIO, we have no idea what to do. Scheduling | |
1473 | * this physical eraseblock for erasure again would cause | |
815bc5f8 | 1474 | * errors again and again. Well, lets switch to R/O mode. |
801c135c | 1475 | */ |
784c1454 | 1476 | goto out_ro; |
801c135c AB |
1477 | |
1478 | /* It is %-EIO, the PEB went bad */ | |
1479 | ||
1480 | if (!ubi->bad_allowed) { | |
1481 | ubi_err("bad physical eraseblock %d detected", pnum); | |
784c1454 AB |
1482 | goto out_ro; |
1483 | } | |
801c135c | 1484 | |
784c1454 | 1485 | spin_lock(&ubi->volumes_lock); |
784c1454 | 1486 | if (ubi->beb_rsvd_pebs == 0) { |
37f758a0 SL |
1487 | if (ubi->avail_pebs == 0) { |
1488 | spin_unlock(&ubi->volumes_lock); | |
1489 | ubi_err("no reserved/available physical eraseblocks"); | |
1490 | goto out_ro; | |
1491 | } | |
1492 | ubi->avail_pebs -= 1; | |
1493 | available_consumed = 1; | |
784c1454 | 1494 | } |
784c1454 | 1495 | spin_unlock(&ubi->volumes_lock); |
801c135c | 1496 | |
52b605d1 | 1497 | ubi_msg("mark PEB %d as bad", pnum); |
784c1454 AB |
1498 | err = ubi_io_mark_bad(ubi, pnum); |
1499 | if (err) | |
1500 | goto out_ro; | |
1501 | ||
1502 | spin_lock(&ubi->volumes_lock); | |
37f758a0 SL |
1503 | if (ubi->beb_rsvd_pebs > 0) { |
1504 | if (available_consumed) { | |
1505 | /* | |
1506 | * The amount of reserved PEBs increased since we last | |
1507 | * checked. | |
1508 | */ | |
1509 | ubi->avail_pebs += 1; | |
1510 | available_consumed = 0; | |
1511 | } | |
1512 | ubi->beb_rsvd_pebs -= 1; | |
1513 | } | |
784c1454 AB |
1514 | ubi->bad_peb_count += 1; |
1515 | ubi->good_peb_count -= 1; | |
1516 | ubi_calculate_reserved(ubi); | |
37f758a0 SL |
1517 | if (available_consumed) |
1518 | ubi_warn("no PEBs in the reserved pool, used an available PEB"); | |
1519 | else if (ubi->beb_rsvd_pebs) | |
52b605d1 AB |
1520 | ubi_msg("%d PEBs left in the reserve", ubi->beb_rsvd_pebs); |
1521 | else | |
37f758a0 | 1522 | ubi_warn("last PEB from the reserve was used"); |
784c1454 AB |
1523 | spin_unlock(&ubi->volumes_lock); |
1524 | ||
1525 | return err; | |
801c135c | 1526 | |
784c1454 | 1527 | out_ro: |
37f758a0 SL |
1528 | if (available_consumed) { |
1529 | spin_lock(&ubi->volumes_lock); | |
1530 | ubi->avail_pebs += 1; | |
1531 | spin_unlock(&ubi->volumes_lock); | |
1532 | } | |
784c1454 | 1533 | ubi_ro_mode(ubi); |
801c135c AB |
1534 | return err; |
1535 | } | |
1536 | ||
1537 | /** | |
85c6e6e2 | 1538 | * ubi_wl_put_peb - return a PEB to the wear-leveling sub-system. |
801c135c | 1539 | * @ubi: UBI device description object |
d36e59e6 JR |
1540 | * @vol_id: the volume ID that last used this PEB |
1541 | * @lnum: the last used logical eraseblock number for the PEB | |
801c135c AB |
1542 | * @pnum: physical eraseblock to return |
1543 | * @torture: if this physical eraseblock has to be tortured | |
1544 | * | |
1545 | * This function is called to return physical eraseblock @pnum to the pool of | |
1546 | * free physical eraseblocks. The @torture flag has to be set if an I/O error | |
1547 | * occurred to this @pnum and it has to be tested. This function returns zero | |
43f9b25a | 1548 | * in case of success, and a negative error code in case of failure. |
801c135c | 1549 | */ |
d36e59e6 JR |
1550 | int ubi_wl_put_peb(struct ubi_device *ubi, int vol_id, int lnum, |
1551 | int pnum, int torture) | |
801c135c AB |
1552 | { |
1553 | int err; | |
1554 | struct ubi_wl_entry *e; | |
1555 | ||
1556 | dbg_wl("PEB %d", pnum); | |
1557 | ubi_assert(pnum >= 0); | |
1558 | ubi_assert(pnum < ubi->peb_count); | |
1559 | ||
43f9b25a | 1560 | retry: |
801c135c | 1561 | spin_lock(&ubi->wl_lock); |
801c135c AB |
1562 | e = ubi->lookuptbl[pnum]; |
1563 | if (e == ubi->move_from) { | |
1564 | /* | |
1565 | * User is putting the physical eraseblock which was selected to | |
1566 | * be moved. It will be scheduled for erasure in the | |
1567 | * wear-leveling worker. | |
1568 | */ | |
43f9b25a | 1569 | dbg_wl("PEB %d is being moved, wait", pnum); |
801c135c | 1570 | spin_unlock(&ubi->wl_lock); |
43f9b25a AB |
1571 | |
1572 | /* Wait for the WL worker by taking the @ubi->move_mutex */ | |
1573 | mutex_lock(&ubi->move_mutex); | |
1574 | mutex_unlock(&ubi->move_mutex); | |
1575 | goto retry; | |
801c135c AB |
1576 | } else if (e == ubi->move_to) { |
1577 | /* | |
1578 | * User is putting the physical eraseblock which was selected | |
1579 | * as the target the data is moved to. It may happen if the EBA | |
85c6e6e2 AB |
1580 | * sub-system already re-mapped the LEB in 'ubi_eba_copy_leb()' |
1581 | * but the WL sub-system has not put the PEB to the "used" tree | |
1582 | * yet, but it is about to do this. So we just set a flag which | |
1583 | * will tell the WL worker that the PEB is not needed anymore | |
1584 | * and should be scheduled for erasure. | |
801c135c AB |
1585 | */ |
1586 | dbg_wl("PEB %d is the target of data moving", pnum); | |
1587 | ubi_assert(!ubi->move_to_put); | |
1588 | ubi->move_to_put = 1; | |
1589 | spin_unlock(&ubi->wl_lock); | |
1590 | return 0; | |
1591 | } else { | |
5abde384 | 1592 | if (in_wl_tree(e, &ubi->used)) { |
7bf523ae | 1593 | self_check_in_wl_tree(ubi, e, &ubi->used); |
23553b2c | 1594 | rb_erase(&e->u.rb, &ubi->used); |
5abde384 | 1595 | } else if (in_wl_tree(e, &ubi->scrub)) { |
7bf523ae | 1596 | self_check_in_wl_tree(ubi, e, &ubi->scrub); |
23553b2c | 1597 | rb_erase(&e->u.rb, &ubi->scrub); |
b86a2c56 | 1598 | } else if (in_wl_tree(e, &ubi->erroneous)) { |
7bf523ae | 1599 | self_check_in_wl_tree(ubi, e, &ubi->erroneous); |
b86a2c56 AB |
1600 | rb_erase(&e->u.rb, &ubi->erroneous); |
1601 | ubi->erroneous_peb_count -= 1; | |
1602 | ubi_assert(ubi->erroneous_peb_count >= 0); | |
815bc5f8 | 1603 | /* Erroneous PEBs should be tortured */ |
b86a2c56 | 1604 | torture = 1; |
43f9b25a | 1605 | } else { |
7b6c32da | 1606 | err = prot_queue_del(ubi, e->pnum); |
43f9b25a AB |
1607 | if (err) { |
1608 | ubi_err("PEB %d not found", pnum); | |
1609 | ubi_ro_mode(ubi); | |
1610 | spin_unlock(&ubi->wl_lock); | |
1611 | return err; | |
1612 | } | |
1613 | } | |
801c135c AB |
1614 | } |
1615 | spin_unlock(&ubi->wl_lock); | |
1616 | ||
d36e59e6 | 1617 | err = schedule_erase(ubi, e, vol_id, lnum, torture); |
801c135c AB |
1618 | if (err) { |
1619 | spin_lock(&ubi->wl_lock); | |
5abde384 | 1620 | wl_tree_add(e, &ubi->used); |
801c135c AB |
1621 | spin_unlock(&ubi->wl_lock); |
1622 | } | |
1623 | ||
1624 | return err; | |
1625 | } | |
1626 | ||
1627 | /** | |
1628 | * ubi_wl_scrub_peb - schedule a physical eraseblock for scrubbing. | |
1629 | * @ubi: UBI device description object | |
1630 | * @pnum: the physical eraseblock to schedule | |
1631 | * | |
1632 | * If a bit-flip in a physical eraseblock is detected, this physical eraseblock | |
1633 | * needs scrubbing. This function schedules a physical eraseblock for | |
1634 | * scrubbing which is done in background. This function returns zero in case of | |
1635 | * success and a negative error code in case of failure. | |
1636 | */ | |
1637 | int ubi_wl_scrub_peb(struct ubi_device *ubi, int pnum) | |
1638 | { | |
1639 | struct ubi_wl_entry *e; | |
1640 | ||
719bb840 | 1641 | ubi_msg("schedule PEB %d for scrubbing", pnum); |
801c135c AB |
1642 | |
1643 | retry: | |
1644 | spin_lock(&ubi->wl_lock); | |
1645 | e = ubi->lookuptbl[pnum]; | |
d3f6e6c6 AB |
1646 | if (e == ubi->move_from || in_wl_tree(e, &ubi->scrub) || |
1647 | in_wl_tree(e, &ubi->erroneous)) { | |
801c135c AB |
1648 | spin_unlock(&ubi->wl_lock); |
1649 | return 0; | |
1650 | } | |
1651 | ||
1652 | if (e == ubi->move_to) { | |
1653 | /* | |
1654 | * This physical eraseblock was used to move data to. The data | |
1655 | * was moved but the PEB was not yet inserted to the proper | |
1656 | * tree. We should just wait a little and let the WL worker | |
1657 | * proceed. | |
1658 | */ | |
1659 | spin_unlock(&ubi->wl_lock); | |
1660 | dbg_wl("the PEB %d is not in proper tree, retry", pnum); | |
1661 | yield(); | |
1662 | goto retry; | |
1663 | } | |
1664 | ||
5abde384 | 1665 | if (in_wl_tree(e, &ubi->used)) { |
7bf523ae | 1666 | self_check_in_wl_tree(ubi, e, &ubi->used); |
23553b2c | 1667 | rb_erase(&e->u.rb, &ubi->used); |
43f9b25a AB |
1668 | } else { |
1669 | int err; | |
1670 | ||
7b6c32da | 1671 | err = prot_queue_del(ubi, e->pnum); |
43f9b25a AB |
1672 | if (err) { |
1673 | ubi_err("PEB %d not found", pnum); | |
1674 | ubi_ro_mode(ubi); | |
1675 | spin_unlock(&ubi->wl_lock); | |
1676 | return err; | |
1677 | } | |
1678 | } | |
801c135c | 1679 | |
5abde384 | 1680 | wl_tree_add(e, &ubi->scrub); |
801c135c AB |
1681 | spin_unlock(&ubi->wl_lock); |
1682 | ||
1683 | /* | |
1684 | * Technically scrubbing is the same as wear-leveling, so it is done | |
1685 | * by the WL worker. | |
1686 | */ | |
8199b901 | 1687 | return ensure_wear_leveling(ubi, 0); |
801c135c AB |
1688 | } |
1689 | ||
1690 | /** | |
1691 | * ubi_wl_flush - flush all pending works. | |
1692 | * @ubi: UBI device description object | |
62f38455 JR |
1693 | * @vol_id: the volume id to flush for |
1694 | * @lnum: the logical eraseblock number to flush for | |
801c135c | 1695 | * |
62f38455 JR |
1696 | * This function executes all pending works for a particular volume id / |
1697 | * logical eraseblock number pair. If either value is set to %UBI_ALL, then it | |
1698 | * acts as a wildcard for all of the corresponding volume numbers or logical | |
1699 | * eraseblock numbers. It returns zero in case of success and a negative error | |
1700 | * code in case of failure. | |
801c135c | 1701 | */ |
62f38455 | 1702 | int ubi_wl_flush(struct ubi_device *ubi, int vol_id, int lnum) |
801c135c | 1703 | { |
62f38455 JR |
1704 | int err = 0; |
1705 | int found = 1; | |
801c135c AB |
1706 | |
1707 | /* | |
7b6c32da | 1708 | * Erase while the pending works queue is not empty, but not more than |
801c135c AB |
1709 | * the number of currently pending works. |
1710 | */ | |
62f38455 JR |
1711 | dbg_wl("flush pending work for LEB %d:%d (%d pending works)", |
1712 | vol_id, lnum, ubi->works_count); | |
593dd33c | 1713 | |
62f38455 JR |
1714 | while (found) { |
1715 | struct ubi_work *wrk; | |
1716 | found = 0; | |
593dd33c | 1717 | |
12027f1b | 1718 | down_read(&ubi->work_sem); |
62f38455 JR |
1719 | spin_lock(&ubi->wl_lock); |
1720 | list_for_each_entry(wrk, &ubi->works, list) { | |
1721 | if ((vol_id == UBI_ALL || wrk->vol_id == vol_id) && | |
1722 | (lnum == UBI_ALL || wrk->lnum == lnum)) { | |
1723 | list_del(&wrk->list); | |
1724 | ubi->works_count -= 1; | |
1725 | ubi_assert(ubi->works_count >= 0); | |
1726 | spin_unlock(&ubi->wl_lock); | |
1727 | ||
1728 | err = wrk->func(ubi, wrk, 0); | |
12027f1b AB |
1729 | if (err) { |
1730 | up_read(&ubi->work_sem); | |
1731 | return err; | |
1732 | } | |
1733 | ||
62f38455 JR |
1734 | spin_lock(&ubi->wl_lock); |
1735 | found = 1; | |
1736 | break; | |
1737 | } | |
1738 | } | |
1739 | spin_unlock(&ubi->wl_lock); | |
12027f1b | 1740 | up_read(&ubi->work_sem); |
801c135c AB |
1741 | } |
1742 | ||
12027f1b AB |
1743 | /* |
1744 | * Make sure all the works which have been done in parallel are | |
1745 | * finished. | |
1746 | */ | |
1747 | down_write(&ubi->work_sem); | |
62f38455 | 1748 | up_write(&ubi->work_sem); |
12027f1b | 1749 | |
62f38455 | 1750 | return err; |
801c135c AB |
1751 | } |
1752 | ||
1753 | /** | |
1754 | * tree_destroy - destroy an RB-tree. | |
1755 | * @root: the root of the tree to destroy | |
1756 | */ | |
1757 | static void tree_destroy(struct rb_root *root) | |
1758 | { | |
1759 | struct rb_node *rb; | |
1760 | struct ubi_wl_entry *e; | |
1761 | ||
1762 | rb = root->rb_node; | |
1763 | while (rb) { | |
1764 | if (rb->rb_left) | |
1765 | rb = rb->rb_left; | |
1766 | else if (rb->rb_right) | |
1767 | rb = rb->rb_right; | |
1768 | else { | |
23553b2c | 1769 | e = rb_entry(rb, struct ubi_wl_entry, u.rb); |
801c135c AB |
1770 | |
1771 | rb = rb_parent(rb); | |
1772 | if (rb) { | |
23553b2c | 1773 | if (rb->rb_left == &e->u.rb) |
801c135c AB |
1774 | rb->rb_left = NULL; |
1775 | else | |
1776 | rb->rb_right = NULL; | |
1777 | } | |
1778 | ||
06b68ba1 | 1779 | kmem_cache_free(ubi_wl_entry_slab, e); |
801c135c AB |
1780 | } |
1781 | } | |
1782 | } | |
1783 | ||
1784 | /** | |
1785 | * ubi_thread - UBI background thread. | |
1786 | * @u: the UBI device description object pointer | |
1787 | */ | |
cdfa788a | 1788 | int ubi_thread(void *u) |
801c135c AB |
1789 | { |
1790 | int failures = 0; | |
1791 | struct ubi_device *ubi = u; | |
1792 | ||
1793 | ubi_msg("background thread \"%s\" started, PID %d", | |
ba25f9dc | 1794 | ubi->bgt_name, task_pid_nr(current)); |
801c135c | 1795 | |
83144186 | 1796 | set_freezable(); |
801c135c AB |
1797 | for (;;) { |
1798 | int err; | |
1799 | ||
1800 | if (kthread_should_stop()) | |
cadb40cc | 1801 | break; |
801c135c AB |
1802 | |
1803 | if (try_to_freeze()) | |
1804 | continue; | |
1805 | ||
1806 | spin_lock(&ubi->wl_lock); | |
1807 | if (list_empty(&ubi->works) || ubi->ro_mode || | |
27a0f2a3 | 1808 | !ubi->thread_enabled || ubi_dbg_is_bgt_disabled(ubi)) { |
801c135c AB |
1809 | set_current_state(TASK_INTERRUPTIBLE); |
1810 | spin_unlock(&ubi->wl_lock); | |
1811 | schedule(); | |
1812 | continue; | |
1813 | } | |
1814 | spin_unlock(&ubi->wl_lock); | |
1815 | ||
1816 | err = do_work(ubi); | |
1817 | if (err) { | |
1818 | ubi_err("%s: work failed with error code %d", | |
1819 | ubi->bgt_name, err); | |
1820 | if (failures++ > WL_MAX_FAILURES) { | |
1821 | /* | |
1822 | * Too many failures, disable the thread and | |
1823 | * switch to read-only mode. | |
1824 | */ | |
1825 | ubi_msg("%s: %d consecutive failures", | |
1826 | ubi->bgt_name, WL_MAX_FAILURES); | |
1827 | ubi_ro_mode(ubi); | |
2ad49887 VG |
1828 | ubi->thread_enabled = 0; |
1829 | continue; | |
801c135c AB |
1830 | } |
1831 | } else | |
1832 | failures = 0; | |
1833 | ||
1834 | cond_resched(); | |
1835 | } | |
1836 | ||
801c135c AB |
1837 | dbg_wl("background thread \"%s\" is killed", ubi->bgt_name); |
1838 | return 0; | |
1839 | } | |
1840 | ||
1841 | /** | |
1842 | * cancel_pending - cancel all pending works. | |
1843 | * @ubi: UBI device description object | |
1844 | */ | |
1845 | static void cancel_pending(struct ubi_device *ubi) | |
1846 | { | |
1847 | while (!list_empty(&ubi->works)) { | |
1848 | struct ubi_work *wrk; | |
1849 | ||
1850 | wrk = list_entry(ubi->works.next, struct ubi_work, list); | |
1851 | list_del(&wrk->list); | |
1852 | wrk->func(ubi, wrk, 1); | |
1853 | ubi->works_count -= 1; | |
1854 | ubi_assert(ubi->works_count >= 0); | |
1855 | } | |
1856 | } | |
1857 | ||
1858 | /** | |
41e0cd9d | 1859 | * ubi_wl_init - initialize the WL sub-system using attaching information. |
801c135c | 1860 | * @ubi: UBI device description object |
a4e6042f | 1861 | * @ai: attaching information |
801c135c AB |
1862 | * |
1863 | * This function returns zero in case of success, and a negative error code in | |
1864 | * case of failure. | |
1865 | */ | |
41e0cd9d | 1866 | int ubi_wl_init(struct ubi_device *ubi, struct ubi_attach_info *ai) |
801c135c | 1867 | { |
8199b901 | 1868 | int err, i, reserved_pebs, found_pebs = 0; |
801c135c | 1869 | struct rb_node *rb1, *rb2; |
517af48c | 1870 | struct ubi_ainf_volume *av; |
2c5ec5ce | 1871 | struct ubi_ainf_peb *aeb, *tmp; |
801c135c AB |
1872 | struct ubi_wl_entry *e; |
1873 | ||
b86a2c56 | 1874 | ubi->used = ubi->erroneous = ubi->free = ubi->scrub = RB_ROOT; |
801c135c | 1875 | spin_lock_init(&ubi->wl_lock); |
43f9b25a | 1876 | mutex_init(&ubi->move_mutex); |
593dd33c | 1877 | init_rwsem(&ubi->work_sem); |
a4e6042f | 1878 | ubi->max_ec = ai->max_ec; |
801c135c | 1879 | INIT_LIST_HEAD(&ubi->works); |
8199b901 RW |
1880 | #ifdef CONFIG_MTD_UBI_FASTMAP |
1881 | INIT_WORK(&ubi->fm_work, update_fastmap_work_fn); | |
1882 | #endif | |
801c135c AB |
1883 | |
1884 | sprintf(ubi->bgt_name, UBI_BGT_NAME_PATTERN, ubi->ubi_num); | |
1885 | ||
801c135c AB |
1886 | err = -ENOMEM; |
1887 | ubi->lookuptbl = kzalloc(ubi->peb_count * sizeof(void *), GFP_KERNEL); | |
1888 | if (!ubi->lookuptbl) | |
cdfa788a | 1889 | return err; |
801c135c | 1890 | |
7b6c32da XX |
1891 | for (i = 0; i < UBI_PROT_QUEUE_LEN; i++) |
1892 | INIT_LIST_HEAD(&ubi->pq[i]); | |
1893 | ubi->pq_head = 0; | |
1894 | ||
a4e6042f | 1895 | list_for_each_entry_safe(aeb, tmp, &ai->erase, u.list) { |
801c135c AB |
1896 | cond_resched(); |
1897 | ||
06b68ba1 | 1898 | e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL); |
801c135c AB |
1899 | if (!e) |
1900 | goto out_free; | |
1901 | ||
2c5ec5ce AB |
1902 | e->pnum = aeb->pnum; |
1903 | e->ec = aeb->ec; | |
8199b901 | 1904 | ubi_assert(!ubi_is_fm_block(ubi, e->pnum)); |
801c135c | 1905 | ubi->lookuptbl[e->pnum] = e; |
d36e59e6 | 1906 | if (schedule_erase(ubi, e, aeb->vol_id, aeb->lnum, 0)) { |
06b68ba1 | 1907 | kmem_cache_free(ubi_wl_entry_slab, e); |
801c135c AB |
1908 | goto out_free; |
1909 | } | |
8199b901 RW |
1910 | |
1911 | found_pebs++; | |
801c135c AB |
1912 | } |
1913 | ||
8199b901 | 1914 | ubi->free_count = 0; |
a4e6042f | 1915 | list_for_each_entry(aeb, &ai->free, u.list) { |
801c135c AB |
1916 | cond_resched(); |
1917 | ||
06b68ba1 | 1918 | e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL); |
801c135c AB |
1919 | if (!e) |
1920 | goto out_free; | |
1921 | ||
2c5ec5ce AB |
1922 | e->pnum = aeb->pnum; |
1923 | e->ec = aeb->ec; | |
801c135c | 1924 | ubi_assert(e->ec >= 0); |
8199b901 RW |
1925 | ubi_assert(!ubi_is_fm_block(ubi, e->pnum)); |
1926 | ||
5abde384 | 1927 | wl_tree_add(e, &ubi->free); |
8199b901 RW |
1928 | ubi->free_count++; |
1929 | ||
801c135c | 1930 | ubi->lookuptbl[e->pnum] = e; |
8199b901 RW |
1931 | |
1932 | found_pebs++; | |
801c135c AB |
1933 | } |
1934 | ||
517af48c AB |
1935 | ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb) { |
1936 | ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb) { | |
801c135c AB |
1937 | cond_resched(); |
1938 | ||
06b68ba1 | 1939 | e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL); |
801c135c AB |
1940 | if (!e) |
1941 | goto out_free; | |
1942 | ||
2c5ec5ce AB |
1943 | e->pnum = aeb->pnum; |
1944 | e->ec = aeb->ec; | |
801c135c | 1945 | ubi->lookuptbl[e->pnum] = e; |
8199b901 | 1946 | |
2c5ec5ce | 1947 | if (!aeb->scrub) { |
801c135c AB |
1948 | dbg_wl("add PEB %d EC %d to the used tree", |
1949 | e->pnum, e->ec); | |
5abde384 | 1950 | wl_tree_add(e, &ubi->used); |
801c135c AB |
1951 | } else { |
1952 | dbg_wl("add PEB %d EC %d to the scrub tree", | |
1953 | e->pnum, e->ec); | |
5abde384 | 1954 | wl_tree_add(e, &ubi->scrub); |
801c135c | 1955 | } |
8199b901 RW |
1956 | |
1957 | found_pebs++; | |
801c135c AB |
1958 | } |
1959 | } | |
1960 | ||
8199b901 RW |
1961 | dbg_wl("found %i PEBs", found_pebs); |
1962 | ||
1963 | if (ubi->fm) | |
1964 | ubi_assert(ubi->good_peb_count == \ | |
1965 | found_pebs + ubi->fm->used_blocks); | |
1966 | else | |
1967 | ubi_assert(ubi->good_peb_count == found_pebs); | |
1968 | ||
1969 | reserved_pebs = WL_RESERVED_PEBS; | |
1970 | #ifdef CONFIG_MTD_UBI_FASTMAP | |
1971 | /* Reserve enough LEBs to store two fastmaps. */ | |
1972 | reserved_pebs += (ubi->fm_size / ubi->leb_size) * 2; | |
1973 | #endif | |
1974 | ||
1975 | if (ubi->avail_pebs < reserved_pebs) { | |
801c135c | 1976 | ubi_err("no enough physical eraseblocks (%d, need %d)", |
8199b901 | 1977 | ubi->avail_pebs, reserved_pebs); |
5fc01ab6 AB |
1978 | if (ubi->corr_peb_count) |
1979 | ubi_err("%d PEBs are corrupted and not used", | |
1980 | ubi->corr_peb_count); | |
801c135c AB |
1981 | goto out_free; |
1982 | } | |
8199b901 RW |
1983 | ubi->avail_pebs -= reserved_pebs; |
1984 | ubi->rsvd_pebs += reserved_pebs; | |
801c135c AB |
1985 | |
1986 | /* Schedule wear-leveling if needed */ | |
8199b901 | 1987 | err = ensure_wear_leveling(ubi, 0); |
801c135c AB |
1988 | if (err) |
1989 | goto out_free; | |
1990 | ||
1991 | return 0; | |
1992 | ||
1993 | out_free: | |
1994 | cancel_pending(ubi); | |
1995 | tree_destroy(&ubi->used); | |
1996 | tree_destroy(&ubi->free); | |
1997 | tree_destroy(&ubi->scrub); | |
1998 | kfree(ubi->lookuptbl); | |
801c135c AB |
1999 | return err; |
2000 | } | |
2001 | ||
2002 | /** | |
7b6c32da | 2003 | * protection_queue_destroy - destroy the protection queue. |
801c135c AB |
2004 | * @ubi: UBI device description object |
2005 | */ | |
7b6c32da | 2006 | static void protection_queue_destroy(struct ubi_device *ubi) |
801c135c | 2007 | { |
7b6c32da XX |
2008 | int i; |
2009 | struct ubi_wl_entry *e, *tmp; | |
801c135c | 2010 | |
7b6c32da XX |
2011 | for (i = 0; i < UBI_PROT_QUEUE_LEN; ++i) { |
2012 | list_for_each_entry_safe(e, tmp, &ubi->pq[i], u.list) { | |
2013 | list_del(&e->u.list); | |
2014 | kmem_cache_free(ubi_wl_entry_slab, e); | |
801c135c AB |
2015 | } |
2016 | } | |
2017 | } | |
2018 | ||
2019 | /** | |
85c6e6e2 | 2020 | * ubi_wl_close - close the wear-leveling sub-system. |
801c135c AB |
2021 | * @ubi: UBI device description object |
2022 | */ | |
2023 | void ubi_wl_close(struct ubi_device *ubi) | |
2024 | { | |
85c6e6e2 | 2025 | dbg_wl("close the WL sub-system"); |
801c135c | 2026 | cancel_pending(ubi); |
7b6c32da | 2027 | protection_queue_destroy(ubi); |
801c135c | 2028 | tree_destroy(&ubi->used); |
b86a2c56 | 2029 | tree_destroy(&ubi->erroneous); |
801c135c AB |
2030 | tree_destroy(&ubi->free); |
2031 | tree_destroy(&ubi->scrub); | |
2032 | kfree(ubi->lookuptbl); | |
801c135c AB |
2033 | } |
2034 | ||
801c135c | 2035 | /** |
7bf523ae | 2036 | * self_check_ec - make sure that the erase counter of a PEB is correct. |
801c135c AB |
2037 | * @ubi: UBI device description object |
2038 | * @pnum: the physical eraseblock number to check | |
2039 | * @ec: the erase counter to check | |
2040 | * | |
2041 | * This function returns zero if the erase counter of physical eraseblock @pnum | |
feddbb34 AB |
2042 | * is equivalent to @ec, and a negative error code if not or if an error |
2043 | * occurred. | |
801c135c | 2044 | */ |
7bf523ae | 2045 | static int self_check_ec(struct ubi_device *ubi, int pnum, int ec) |
801c135c AB |
2046 | { |
2047 | int err; | |
2048 | long long read_ec; | |
2049 | struct ubi_ec_hdr *ec_hdr; | |
2050 | ||
64575574 | 2051 | if (!ubi_dbg_chk_gen(ubi)) |
92d124f5 AB |
2052 | return 0; |
2053 | ||
33818bbb | 2054 | ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_NOFS); |
801c135c AB |
2055 | if (!ec_hdr) |
2056 | return -ENOMEM; | |
2057 | ||
2058 | err = ubi_io_read_ec_hdr(ubi, pnum, ec_hdr, 0); | |
2059 | if (err && err != UBI_IO_BITFLIPS) { | |
2060 | /* The header does not have to exist */ | |
2061 | err = 0; | |
2062 | goto out_free; | |
2063 | } | |
2064 | ||
3261ebd7 | 2065 | read_ec = be64_to_cpu(ec_hdr->ec); |
8199b901 | 2066 | if (ec != read_ec && read_ec - ec > 1) { |
7bf523ae | 2067 | ubi_err("self-check failed for PEB %d", pnum); |
801c135c | 2068 | ubi_err("read EC is %lld, should be %d", read_ec, ec); |
25886a36 | 2069 | dump_stack(); |
801c135c AB |
2070 | err = 1; |
2071 | } else | |
2072 | err = 0; | |
2073 | ||
2074 | out_free: | |
2075 | kfree(ec_hdr); | |
2076 | return err; | |
2077 | } | |
2078 | ||
2079 | /** | |
7bf523ae | 2080 | * self_check_in_wl_tree - check that wear-leveling entry is in WL RB-tree. |
d99383b0 | 2081 | * @ubi: UBI device description object |
801c135c AB |
2082 | * @e: the wear-leveling entry to check |
2083 | * @root: the root of the tree | |
2084 | * | |
adbf05e3 AB |
2085 | * This function returns zero if @e is in the @root RB-tree and %-EINVAL if it |
2086 | * is not. | |
801c135c | 2087 | */ |
7bf523ae AB |
2088 | static int self_check_in_wl_tree(const struct ubi_device *ubi, |
2089 | struct ubi_wl_entry *e, struct rb_root *root) | |
801c135c | 2090 | { |
64575574 | 2091 | if (!ubi_dbg_chk_gen(ubi)) |
92d124f5 AB |
2092 | return 0; |
2093 | ||
801c135c AB |
2094 | if (in_wl_tree(e, root)) |
2095 | return 0; | |
2096 | ||
7bf523ae | 2097 | ubi_err("self-check failed for PEB %d, EC %d, RB-tree %p ", |
801c135c | 2098 | e->pnum, e->ec, root); |
25886a36 | 2099 | dump_stack(); |
adbf05e3 | 2100 | return -EINVAL; |
801c135c AB |
2101 | } |
2102 | ||
7b6c32da | 2103 | /** |
7bf523ae | 2104 | * self_check_in_pq - check if wear-leveling entry is in the protection |
7b6c32da XX |
2105 | * queue. |
2106 | * @ubi: UBI device description object | |
2107 | * @e: the wear-leveling entry to check | |
2108 | * | |
adbf05e3 | 2109 | * This function returns zero if @e is in @ubi->pq and %-EINVAL if it is not. |
7b6c32da | 2110 | */ |
7bf523ae AB |
2111 | static int self_check_in_pq(const struct ubi_device *ubi, |
2112 | struct ubi_wl_entry *e) | |
7b6c32da XX |
2113 | { |
2114 | struct ubi_wl_entry *p; | |
2115 | int i; | |
2116 | ||
64575574 | 2117 | if (!ubi_dbg_chk_gen(ubi)) |
92d124f5 AB |
2118 | return 0; |
2119 | ||
7b6c32da XX |
2120 | for (i = 0; i < UBI_PROT_QUEUE_LEN; ++i) |
2121 | list_for_each_entry(p, &ubi->pq[i], u.list) | |
2122 | if (p == e) | |
2123 | return 0; | |
2124 | ||
7bf523ae | 2125 | ubi_err("self-check failed for PEB %d, EC %d, Protect queue", |
7b6c32da | 2126 | e->pnum, e->ec); |
25886a36 | 2127 | dump_stack(); |
adbf05e3 | 2128 | return -EINVAL; |
7b6c32da | 2129 | } |