]>
Commit | Line | Data |
---|---|---|
1a59d1b8 | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
801c135c AB |
2 | /* |
3 | * Copyright (c) International Business Machines Corp., 2006 | |
4 | * | |
801c135c AB |
5 | * Authors: Artem Bityutskiy (Битюцкий Артём), Thomas Gleixner |
6 | */ | |
7 | ||
8 | /* | |
85c6e6e2 | 9 | * UBI wear-leveling sub-system. |
801c135c | 10 | * |
85c6e6e2 | 11 | * This sub-system is responsible for wear-leveling. It works in terms of |
7b6c32da | 12 | * physical eraseblocks and erase counters and knows nothing about logical |
85c6e6e2 AB |
13 | * eraseblocks, volumes, etc. From this sub-system's perspective all physical |
14 | * eraseblocks are of two types - used and free. Used physical eraseblocks are | |
15 | * those that were "get" by the 'ubi_wl_get_peb()' function, and free physical | |
16 | * eraseblocks are those that were put by the 'ubi_wl_put_peb()' function. | |
801c135c AB |
17 | * |
18 | * Physical eraseblocks returned by 'ubi_wl_get_peb()' have only erase counter | |
85c6e6e2 | 19 | * header. The rest of the physical eraseblock contains only %0xFF bytes. |
801c135c | 20 | * |
85c6e6e2 | 21 | * When physical eraseblocks are returned to the WL sub-system by means of the |
801c135c AB |
22 | * 'ubi_wl_put_peb()' function, they are scheduled for erasure. The erasure is |
23 | * done asynchronously in context of the per-UBI device background thread, | |
85c6e6e2 | 24 | * which is also managed by the WL sub-system. |
801c135c AB |
25 | * |
26 | * The wear-leveling is ensured by means of moving the contents of used | |
27 | * physical eraseblocks with low erase counter to free physical eraseblocks | |
28 | * with high erase counter. | |
29 | * | |
85c6e6e2 AB |
30 | * If the WL sub-system fails to erase a physical eraseblock, it marks it as |
31 | * bad. | |
801c135c | 32 | * |
85c6e6e2 AB |
33 | * This sub-system is also responsible for scrubbing. If a bit-flip is detected |
34 | * in a physical eraseblock, it has to be moved. Technically this is the same | |
35 | * as moving it for wear-leveling reasons. | |
801c135c | 36 | * |
85c6e6e2 AB |
37 | * As it was said, for the UBI sub-system all physical eraseblocks are either |
38 | * "free" or "used". Free eraseblock are kept in the @wl->free RB-tree, while | |
b86a2c56 AB |
39 | * used eraseblocks are kept in @wl->used, @wl->erroneous, or @wl->scrub |
40 | * RB-trees, as well as (temporarily) in the @wl->pq queue. | |
7b6c32da XX |
41 | * |
42 | * When the WL sub-system returns a physical eraseblock, the physical | |
43 | * eraseblock is protected from being moved for some "time". For this reason, | |
44 | * the physical eraseblock is not directly moved from the @wl->free tree to the | |
45 | * @wl->used tree. There is a protection queue in between where this | |
46 | * physical eraseblock is temporarily stored (@wl->pq). | |
47 | * | |
48 | * All this protection stuff is needed because: | |
49 | * o we don't want to move physical eraseblocks just after we have given them | |
50 | * to the user; instead, we first want to let users fill them up with data; | |
51 | * | |
52 | * o there is a chance that the user will put the physical eraseblock very | |
44156267 | 53 | * soon, so it makes sense not to move it for some time, but wait. |
7b6c32da XX |
54 | * |
55 | * Physical eraseblocks stay protected only for limited time. But the "time" is | |
56 | * measured in erase cycles in this case. This is implemented with help of the | |
57 | * protection queue. Eraseblocks are put to the tail of this queue when they | |
58 | * are returned by the 'ubi_wl_get_peb()', and eraseblocks are removed from the | |
59 | * head of the queue on each erase operation (for any eraseblock). So the | |
60 | * length of the queue defines how may (global) erase cycles PEBs are protected. | |
61 | * | |
62 | * To put it differently, each physical eraseblock has 2 main states: free and | |
63 | * used. The former state corresponds to the @wl->free tree. The latter state | |
64 | * is split up on several sub-states: | |
65 | * o the WL movement is allowed (@wl->used tree); | |
815bc5f8 | 66 | * o the WL movement is disallowed (@wl->erroneous) because the PEB is |
b86a2c56 | 67 | * erroneous - e.g., there was a read error; |
7b6c32da XX |
68 | * o the WL movement is temporarily prohibited (@wl->pq queue); |
69 | * o scrubbing is needed (@wl->scrub tree). | |
70 | * | |
71 | * Depending on the sub-state, wear-leveling entries of the used physical | |
72 | * eraseblocks may be kept in one of those structures. | |
801c135c AB |
73 | * |
74 | * Note, in this implementation, we keep a small in-RAM object for each physical | |
75 | * eraseblock. This is surely not a scalable solution. But it appears to be good | |
76 | * enough for moderately large flashes and it is simple. In future, one may | |
85c6e6e2 | 77 | * re-work this sub-system and make it more scalable. |
801c135c | 78 | * |
85c6e6e2 AB |
79 | * At the moment this sub-system does not utilize the sequence number, which |
80 | * was introduced relatively recently. But it would be wise to do this because | |
81 | * the sequence number of a logical eraseblock characterizes how old is it. For | |
801c135c AB |
82 | * example, when we move a PEB with low erase counter, and we need to pick the |
83 | * target PEB, we pick a PEB with the highest EC if our PEB is "old" and we | |
84 | * pick target PEB with an average EC if our PEB is not very "old". This is a | |
85c6e6e2 | 85 | * room for future re-works of the WL sub-system. |
801c135c AB |
86 | */ |
87 | ||
88 | #include <linux/slab.h> | |
89 | #include <linux/crc32.h> | |
90 | #include <linux/freezer.h> | |
91 | #include <linux/kthread.h> | |
92 | #include "ubi.h" | |
78d6d497 | 93 | #include "wl.h" |
801c135c AB |
94 | |
95 | /* Number of physical eraseblocks reserved for wear-leveling purposes */ | |
96 | #define WL_RESERVED_PEBS 1 | |
97 | ||
801c135c AB |
98 | /* |
99 | * Maximum difference between two erase counters. If this threshold is | |
85c6e6e2 AB |
100 | * exceeded, the WL sub-system starts moving data from used physical |
101 | * eraseblocks with low erase counter to free physical eraseblocks with high | |
102 | * erase counter. | |
801c135c AB |
103 | */ |
104 | #define UBI_WL_THRESHOLD CONFIG_MTD_UBI_WL_THRESHOLD | |
105 | ||
106 | /* | |
85c6e6e2 | 107 | * When a physical eraseblock is moved, the WL sub-system has to pick the target |
801c135c AB |
108 | * physical eraseblock to move to. The simplest way would be just to pick the |
109 | * one with the highest erase counter. But in certain workloads this could lead | |
110 | * to an unlimited wear of one or few physical eraseblock. Indeed, imagine a | |
111 | * situation when the picked physical eraseblock is constantly erased after the | |
112 | * data is written to it. So, we have a constant which limits the highest erase | |
85c6e6e2 | 113 | * counter of the free physical eraseblock to pick. Namely, the WL sub-system |
025dfdaf | 114 | * does not pick eraseblocks with erase counter greater than the lowest erase |
801c135c AB |
115 | * counter plus %WL_FREE_MAX_DIFF. |
116 | */ | |
117 | #define WL_FREE_MAX_DIFF (2*UBI_WL_THRESHOLD) | |
118 | ||
119 | /* | |
120 | * Maximum number of consecutive background thread failures which is enough to | |
121 | * switch to read-only mode. | |
122 | */ | |
123 | #define WL_MAX_FAILURES 32 | |
124 | ||
7bf523ae AB |
125 | static int self_check_ec(struct ubi_device *ubi, int pnum, int ec); |
126 | static int self_check_in_wl_tree(const struct ubi_device *ubi, | |
127 | struct ubi_wl_entry *e, struct rb_root *root); | |
128 | static int self_check_in_pq(const struct ubi_device *ubi, | |
129 | struct ubi_wl_entry *e); | |
801c135c | 130 | |
801c135c AB |
131 | /** |
132 | * wl_tree_add - add a wear-leveling entry to a WL RB-tree. | |
133 | * @e: the wear-leveling entry to add | |
134 | * @root: the root of the tree | |
135 | * | |
136 | * Note, we use (erase counter, physical eraseblock number) pairs as keys in | |
137 | * the @ubi->used and @ubi->free RB-trees. | |
138 | */ | |
139 | static void wl_tree_add(struct ubi_wl_entry *e, struct rb_root *root) | |
140 | { | |
141 | struct rb_node **p, *parent = NULL; | |
142 | ||
143 | p = &root->rb_node; | |
144 | while (*p) { | |
145 | struct ubi_wl_entry *e1; | |
146 | ||
147 | parent = *p; | |
23553b2c | 148 | e1 = rb_entry(parent, struct ubi_wl_entry, u.rb); |
801c135c AB |
149 | |
150 | if (e->ec < e1->ec) | |
151 | p = &(*p)->rb_left; | |
152 | else if (e->ec > e1->ec) | |
153 | p = &(*p)->rb_right; | |
154 | else { | |
155 | ubi_assert(e->pnum != e1->pnum); | |
156 | if (e->pnum < e1->pnum) | |
157 | p = &(*p)->rb_left; | |
158 | else | |
159 | p = &(*p)->rb_right; | |
160 | } | |
161 | } | |
162 | ||
23553b2c XX |
163 | rb_link_node(&e->u.rb, parent, p); |
164 | rb_insert_color(&e->u.rb, root); | |
801c135c AB |
165 | } |
166 | ||
ee59ba8b RW |
167 | /** |
168 | * wl_tree_destroy - destroy a wear-leveling entry. | |
169 | * @ubi: UBI device description object | |
170 | * @e: the wear-leveling entry to add | |
171 | * | |
172 | * This function destroys a wear leveling entry and removes | |
173 | * the reference from the lookup table. | |
174 | */ | |
175 | static void wl_entry_destroy(struct ubi_device *ubi, struct ubi_wl_entry *e) | |
176 | { | |
177 | ubi->lookuptbl[e->pnum] = NULL; | |
178 | kmem_cache_free(ubi_wl_entry_slab, e); | |
179 | } | |
180 | ||
801c135c AB |
181 | /** |
182 | * do_work - do one pending work. | |
183 | * @ubi: UBI device description object | |
184 | * | |
185 | * This function returns zero in case of success and a negative error code in | |
186 | * case of failure. | |
187 | */ | |
188 | static int do_work(struct ubi_device *ubi) | |
189 | { | |
190 | int err; | |
191 | struct ubi_work *wrk; | |
192 | ||
43f9b25a AB |
193 | cond_resched(); |
194 | ||
593dd33c AB |
195 | /* |
196 | * @ubi->work_sem is used to synchronize with the workers. Workers take | |
197 | * it in read mode, so many of them may be doing works at a time. But | |
198 | * the queue flush code has to be sure the whole queue of works is | |
199 | * done, and it takes the mutex in write mode. | |
200 | */ | |
201 | down_read(&ubi->work_sem); | |
801c135c | 202 | spin_lock(&ubi->wl_lock); |
801c135c AB |
203 | if (list_empty(&ubi->works)) { |
204 | spin_unlock(&ubi->wl_lock); | |
593dd33c | 205 | up_read(&ubi->work_sem); |
801c135c AB |
206 | return 0; |
207 | } | |
208 | ||
209 | wrk = list_entry(ubi->works.next, struct ubi_work, list); | |
210 | list_del(&wrk->list); | |
16f557ec AB |
211 | ubi->works_count -= 1; |
212 | ubi_assert(ubi->works_count >= 0); | |
801c135c AB |
213 | spin_unlock(&ubi->wl_lock); |
214 | ||
215 | /* | |
216 | * Call the worker function. Do not touch the work structure | |
217 | * after this call as it will have been freed or reused by that | |
218 | * time by the worker function. | |
219 | */ | |
220 | err = wrk->func(ubi, wrk, 0); | |
221 | if (err) | |
32608703 | 222 | ubi_err(ubi, "work failed with error code %d", err); |
593dd33c | 223 | up_read(&ubi->work_sem); |
16f557ec | 224 | |
801c135c AB |
225 | return err; |
226 | } | |
227 | ||
801c135c AB |
228 | /** |
229 | * in_wl_tree - check if wear-leveling entry is present in a WL RB-tree. | |
230 | * @e: the wear-leveling entry to check | |
231 | * @root: the root of the tree | |
232 | * | |
233 | * This function returns non-zero if @e is in the @root RB-tree and zero if it | |
234 | * is not. | |
235 | */ | |
236 | static int in_wl_tree(struct ubi_wl_entry *e, struct rb_root *root) | |
237 | { | |
238 | struct rb_node *p; | |
239 | ||
240 | p = root->rb_node; | |
241 | while (p) { | |
242 | struct ubi_wl_entry *e1; | |
243 | ||
23553b2c | 244 | e1 = rb_entry(p, struct ubi_wl_entry, u.rb); |
801c135c AB |
245 | |
246 | if (e->pnum == e1->pnum) { | |
247 | ubi_assert(e == e1); | |
248 | return 1; | |
249 | } | |
250 | ||
251 | if (e->ec < e1->ec) | |
252 | p = p->rb_left; | |
253 | else if (e->ec > e1->ec) | |
254 | p = p->rb_right; | |
255 | else { | |
256 | ubi_assert(e->pnum != e1->pnum); | |
257 | if (e->pnum < e1->pnum) | |
258 | p = p->rb_left; | |
259 | else | |
260 | p = p->rb_right; | |
261 | } | |
262 | } | |
263 | ||
264 | return 0; | |
265 | } | |
266 | ||
b32b78f8 RW |
267 | /** |
268 | * in_pq - check if a wear-leveling entry is present in the protection queue. | |
269 | * @ubi: UBI device description object | |
270 | * @e: the wear-leveling entry to check | |
271 | * | |
272 | * This function returns non-zero if @e is in the protection queue and zero | |
273 | * if it is not. | |
274 | */ | |
275 | static inline int in_pq(const struct ubi_device *ubi, struct ubi_wl_entry *e) | |
276 | { | |
277 | struct ubi_wl_entry *p; | |
278 | int i; | |
279 | ||
280 | for (i = 0; i < UBI_PROT_QUEUE_LEN; ++i) | |
281 | list_for_each_entry(p, &ubi->pq[i], u.list) | |
282 | if (p == e) | |
283 | return 1; | |
284 | ||
285 | return 0; | |
286 | } | |
287 | ||
801c135c | 288 | /** |
7b6c32da | 289 | * prot_queue_add - add physical eraseblock to the protection queue. |
801c135c AB |
290 | * @ubi: UBI device description object |
291 | * @e: the physical eraseblock to add | |
801c135c | 292 | * |
7b6c32da XX |
293 | * This function adds @e to the tail of the protection queue @ubi->pq, where |
294 | * @e will stay for %UBI_PROT_QUEUE_LEN erase operations and will be | |
295 | * temporarily protected from the wear-leveling worker. Note, @wl->lock has to | |
296 | * be locked. | |
801c135c | 297 | */ |
7b6c32da | 298 | static void prot_queue_add(struct ubi_device *ubi, struct ubi_wl_entry *e) |
801c135c | 299 | { |
7b6c32da | 300 | int pq_tail = ubi->pq_head - 1; |
801c135c | 301 | |
7b6c32da XX |
302 | if (pq_tail < 0) |
303 | pq_tail = UBI_PROT_QUEUE_LEN - 1; | |
304 | ubi_assert(pq_tail >= 0 && pq_tail < UBI_PROT_QUEUE_LEN); | |
305 | list_add_tail(&e->u.list, &ubi->pq[pq_tail]); | |
306 | dbg_wl("added PEB %d EC %d to the protection queue", e->pnum, e->ec); | |
801c135c AB |
307 | } |
308 | ||
309 | /** | |
310 | * find_wl_entry - find wear-leveling entry closest to certain erase counter. | |
8199b901 | 311 | * @ubi: UBI device description object |
801c135c | 312 | * @root: the RB-tree where to look for |
add8287e | 313 | * @diff: maximum possible difference from the smallest erase counter |
801c135c AB |
314 | * |
315 | * This function looks for a wear leveling entry with erase counter closest to | |
add8287e | 316 | * min + @diff, where min is the smallest erase counter. |
801c135c | 317 | */ |
8199b901 RW |
318 | static struct ubi_wl_entry *find_wl_entry(struct ubi_device *ubi, |
319 | struct rb_root *root, int diff) | |
801c135c AB |
320 | { |
321 | struct rb_node *p; | |
8199b901 | 322 | struct ubi_wl_entry *e, *prev_e = NULL; |
add8287e | 323 | int max; |
801c135c | 324 | |
23553b2c | 325 | e = rb_entry(rb_first(root), struct ubi_wl_entry, u.rb); |
add8287e | 326 | max = e->ec + diff; |
801c135c AB |
327 | |
328 | p = root->rb_node; | |
329 | while (p) { | |
330 | struct ubi_wl_entry *e1; | |
331 | ||
23553b2c | 332 | e1 = rb_entry(p, struct ubi_wl_entry, u.rb); |
801c135c AB |
333 | if (e1->ec >= max) |
334 | p = p->rb_left; | |
335 | else { | |
336 | p = p->rb_right; | |
8199b901 | 337 | prev_e = e; |
801c135c AB |
338 | e = e1; |
339 | } | |
340 | } | |
341 | ||
8199b901 RW |
342 | /* If no fastmap has been written and this WL entry can be used |
343 | * as anchor PEB, hold it back and return the second best WL entry | |
344 | * such that fastmap can use the anchor PEB later. */ | |
345 | if (prev_e && !ubi->fm_disabled && | |
346 | !ubi->fm && e->pnum < UBI_FM_MAX_START) | |
347 | return prev_e; | |
348 | ||
801c135c AB |
349 | return e; |
350 | } | |
351 | ||
352 | /** | |
8199b901 RW |
353 | * find_mean_wl_entry - find wear-leveling entry with medium erase counter. |
354 | * @ubi: UBI device description object | |
355 | * @root: the RB-tree where to look for | |
356 | * | |
357 | * This function looks for a wear leveling entry with medium erase counter, | |
358 | * but not greater or equivalent than the lowest erase counter plus | |
359 | * %WL_FREE_MAX_DIFF/2. | |
360 | */ | |
361 | static struct ubi_wl_entry *find_mean_wl_entry(struct ubi_device *ubi, | |
362 | struct rb_root *root) | |
363 | { | |
364 | struct ubi_wl_entry *e, *first, *last; | |
365 | ||
366 | first = rb_entry(rb_first(root), struct ubi_wl_entry, u.rb); | |
367 | last = rb_entry(rb_last(root), struct ubi_wl_entry, u.rb); | |
368 | ||
369 | if (last->ec - first->ec < WL_FREE_MAX_DIFF) { | |
370 | e = rb_entry(root->rb_node, struct ubi_wl_entry, u.rb); | |
371 | ||
8199b901 RW |
372 | /* If no fastmap has been written and this WL entry can be used |
373 | * as anchor PEB, hold it back and return the second best | |
374 | * WL entry such that fastmap can use the anchor PEB later. */ | |
2f84c246 | 375 | e = may_reserve_for_fm(ubi, e, root); |
8199b901 RW |
376 | } else |
377 | e = find_wl_entry(ubi, root, WL_FREE_MAX_DIFF/2); | |
378 | ||
379 | return e; | |
380 | } | |
381 | ||
8199b901 | 382 | /** |
78d6d497 | 383 | * wl_get_wle - get a mean wl entry to be used by ubi_wl_get_peb() or |
691a8705 RW |
384 | * refill_wl_user_pool(). |
385 | * @ubi: UBI device description object | |
386 | * | |
387 | * This function returns a a wear leveling entry in case of success and | |
388 | * NULL in case of failure. | |
389 | */ | |
390 | static struct ubi_wl_entry *wl_get_wle(struct ubi_device *ubi) | |
391 | { | |
392 | struct ubi_wl_entry *e; | |
393 | ||
394 | e = find_mean_wl_entry(ubi, &ubi->free); | |
395 | if (!e) { | |
396 | ubi_err(ubi, "no free eraseblocks"); | |
397 | return NULL; | |
398 | } | |
399 | ||
400 | self_check_in_wl_tree(ubi, e, &ubi->free); | |
401 | ||
402 | /* | |
403 | * Move the physical eraseblock to the protection queue where it will | |
404 | * be protected from being moved for some time. | |
405 | */ | |
406 | rb_erase(&e->u.rb, &ubi->free); | |
407 | ubi->free_count--; | |
408 | dbg_wl("PEB %d EC %d", e->pnum, e->ec); | |
409 | ||
410 | return e; | |
411 | } | |
412 | ||
801c135c | 413 | /** |
7b6c32da | 414 | * prot_queue_del - remove a physical eraseblock from the protection queue. |
801c135c AB |
415 | * @ubi: UBI device description object |
416 | * @pnum: the physical eraseblock to remove | |
43f9b25a | 417 | * |
7b6c32da XX |
418 | * This function deletes PEB @pnum from the protection queue and returns zero |
419 | * in case of success and %-ENODEV if the PEB was not found. | |
801c135c | 420 | */ |
7b6c32da | 421 | static int prot_queue_del(struct ubi_device *ubi, int pnum) |
801c135c | 422 | { |
7b6c32da | 423 | struct ubi_wl_entry *e; |
801c135c | 424 | |
7b6c32da XX |
425 | e = ubi->lookuptbl[pnum]; |
426 | if (!e) | |
427 | return -ENODEV; | |
801c135c | 428 | |
7bf523ae | 429 | if (self_check_in_pq(ubi, e)) |
7b6c32da | 430 | return -ENODEV; |
43f9b25a | 431 | |
7b6c32da XX |
432 | list_del(&e->u.list); |
433 | dbg_wl("deleted PEB %d from the protection queue", e->pnum); | |
43f9b25a | 434 | return 0; |
801c135c AB |
435 | } |
436 | ||
437 | /** | |
438 | * sync_erase - synchronously erase a physical eraseblock. | |
439 | * @ubi: UBI device description object | |
440 | * @e: the the physical eraseblock to erase | |
441 | * @torture: if the physical eraseblock has to be tortured | |
442 | * | |
443 | * This function returns zero in case of success and a negative error code in | |
444 | * case of failure. | |
445 | */ | |
9c9ec147 AB |
446 | static int sync_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, |
447 | int torture) | |
801c135c AB |
448 | { |
449 | int err; | |
450 | struct ubi_ec_hdr *ec_hdr; | |
451 | unsigned long long ec = e->ec; | |
452 | ||
453 | dbg_wl("erase PEB %d, old EC %llu", e->pnum, ec); | |
454 | ||
7bf523ae | 455 | err = self_check_ec(ubi, e->pnum, e->ec); |
adbf05e3 | 456 | if (err) |
801c135c AB |
457 | return -EINVAL; |
458 | ||
33818bbb | 459 | ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_NOFS); |
801c135c AB |
460 | if (!ec_hdr) |
461 | return -ENOMEM; | |
462 | ||
463 | err = ubi_io_sync_erase(ubi, e->pnum, torture); | |
464 | if (err < 0) | |
465 | goto out_free; | |
466 | ||
467 | ec += err; | |
468 | if (ec > UBI_MAX_ERASECOUNTER) { | |
469 | /* | |
470 | * Erase counter overflow. Upgrade UBI and use 64-bit | |
471 | * erase counters internally. | |
472 | */ | |
32608703 | 473 | ubi_err(ubi, "erase counter overflow at PEB %d, EC %llu", |
801c135c AB |
474 | e->pnum, ec); |
475 | err = -EINVAL; | |
476 | goto out_free; | |
477 | } | |
478 | ||
479 | dbg_wl("erased PEB %d, new EC %llu", e->pnum, ec); | |
480 | ||
3261ebd7 | 481 | ec_hdr->ec = cpu_to_be64(ec); |
801c135c AB |
482 | |
483 | err = ubi_io_write_ec_hdr(ubi, e->pnum, ec_hdr); | |
484 | if (err) | |
485 | goto out_free; | |
486 | ||
487 | e->ec = ec; | |
488 | spin_lock(&ubi->wl_lock); | |
489 | if (e->ec > ubi->max_ec) | |
490 | ubi->max_ec = e->ec; | |
491 | spin_unlock(&ubi->wl_lock); | |
492 | ||
493 | out_free: | |
494 | kfree(ec_hdr); | |
495 | return err; | |
496 | } | |
497 | ||
498 | /** | |
7b6c32da | 499 | * serve_prot_queue - check if it is time to stop protecting PEBs. |
801c135c AB |
500 | * @ubi: UBI device description object |
501 | * | |
7b6c32da XX |
502 | * This function is called after each erase operation and removes PEBs from the |
503 | * tail of the protection queue. These PEBs have been protected for long enough | |
504 | * and should be moved to the used tree. | |
801c135c | 505 | */ |
7b6c32da | 506 | static void serve_prot_queue(struct ubi_device *ubi) |
801c135c | 507 | { |
7b6c32da XX |
508 | struct ubi_wl_entry *e, *tmp; |
509 | int count; | |
801c135c AB |
510 | |
511 | /* | |
512 | * There may be several protected physical eraseblock to remove, | |
513 | * process them all. | |
514 | */ | |
7b6c32da XX |
515 | repeat: |
516 | count = 0; | |
517 | spin_lock(&ubi->wl_lock); | |
518 | list_for_each_entry_safe(e, tmp, &ubi->pq[ubi->pq_head], u.list) { | |
519 | dbg_wl("PEB %d EC %d protection over, move to used tree", | |
520 | e->pnum, e->ec); | |
801c135c | 521 | |
7b6c32da XX |
522 | list_del(&e->u.list); |
523 | wl_tree_add(e, &ubi->used); | |
524 | if (count++ > 32) { | |
525 | /* | |
526 | * Let's be nice and avoid holding the spinlock for | |
527 | * too long. | |
528 | */ | |
801c135c | 529 | spin_unlock(&ubi->wl_lock); |
7b6c32da XX |
530 | cond_resched(); |
531 | goto repeat; | |
801c135c | 532 | } |
801c135c | 533 | } |
7b6c32da XX |
534 | |
535 | ubi->pq_head += 1; | |
536 | if (ubi->pq_head == UBI_PROT_QUEUE_LEN) | |
537 | ubi->pq_head = 0; | |
538 | ubi_assert(ubi->pq_head >= 0 && ubi->pq_head < UBI_PROT_QUEUE_LEN); | |
539 | spin_unlock(&ubi->wl_lock); | |
801c135c AB |
540 | } |
541 | ||
542 | /** | |
8199b901 | 543 | * __schedule_ubi_work - schedule a work. |
801c135c AB |
544 | * @ubi: UBI device description object |
545 | * @wrk: the work to schedule | |
546 | * | |
7b6c32da | 547 | * This function adds a work defined by @wrk to the tail of the pending works |
e3e00445 | 548 | * list. Can only be used if ubi->work_sem is already held in read mode! |
801c135c | 549 | */ |
8199b901 | 550 | static void __schedule_ubi_work(struct ubi_device *ubi, struct ubi_work *wrk) |
801c135c AB |
551 | { |
552 | spin_lock(&ubi->wl_lock); | |
553 | list_add_tail(&wrk->list, &ubi->works); | |
554 | ubi_assert(ubi->works_count >= 0); | |
555 | ubi->works_count += 1; | |
27a0f2a3 | 556 | if (ubi->thread_enabled && !ubi_dbg_is_bgt_disabled(ubi)) |
801c135c AB |
557 | wake_up_process(ubi->bgt_thread); |
558 | spin_unlock(&ubi->wl_lock); | |
559 | } | |
560 | ||
8199b901 RW |
561 | /** |
562 | * schedule_ubi_work - schedule a work. | |
563 | * @ubi: UBI device description object | |
564 | * @wrk: the work to schedule | |
565 | * | |
566 | * This function adds a work defined by @wrk to the tail of the pending works | |
567 | * list. | |
568 | */ | |
569 | static void schedule_ubi_work(struct ubi_device *ubi, struct ubi_work *wrk) | |
570 | { | |
571 | down_read(&ubi->work_sem); | |
572 | __schedule_ubi_work(ubi, wrk); | |
573 | up_read(&ubi->work_sem); | |
574 | } | |
575 | ||
801c135c | 576 | static int erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk, |
849271a4 | 577 | int shutdown); |
801c135c AB |
578 | |
579 | /** | |
580 | * schedule_erase - schedule an erase work. | |
581 | * @ubi: UBI device description object | |
582 | * @e: the WL entry of the physical eraseblock to erase | |
d36e59e6 JR |
583 | * @vol_id: the volume ID that last used this PEB |
584 | * @lnum: the last used logical eraseblock number for the PEB | |
801c135c AB |
585 | * @torture: if the physical eraseblock has to be tortured |
586 | * | |
587 | * This function returns zero in case of success and a %-ENOMEM in case of | |
588 | * failure. | |
589 | */ | |
590 | static int schedule_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, | |
2e8f08de | 591 | int vol_id, int lnum, int torture, bool nested) |
801c135c AB |
592 | { |
593 | struct ubi_work *wl_wrk; | |
594 | ||
8199b901 | 595 | ubi_assert(e); |
8199b901 | 596 | |
801c135c AB |
597 | dbg_wl("schedule erasure of PEB %d, EC %d, torture %d", |
598 | e->pnum, e->ec, torture); | |
599 | ||
33818bbb | 600 | wl_wrk = kmalloc(sizeof(struct ubi_work), GFP_NOFS); |
801c135c AB |
601 | if (!wl_wrk) |
602 | return -ENOMEM; | |
603 | ||
604 | wl_wrk->func = &erase_worker; | |
605 | wl_wrk->e = e; | |
d36e59e6 JR |
606 | wl_wrk->vol_id = vol_id; |
607 | wl_wrk->lnum = lnum; | |
801c135c AB |
608 | wl_wrk->torture = torture; |
609 | ||
2e8f08de RW |
610 | if (nested) |
611 | __schedule_ubi_work(ubi, wl_wrk); | |
612 | else | |
613 | schedule_ubi_work(ubi, wl_wrk); | |
801c135c AB |
614 | return 0; |
615 | } | |
616 | ||
1a31b20c | 617 | static int __erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk); |
8199b901 RW |
618 | /** |
619 | * do_sync_erase - run the erase worker synchronously. | |
620 | * @ubi: UBI device description object | |
621 | * @e: the WL entry of the physical eraseblock to erase | |
622 | * @vol_id: the volume ID that last used this PEB | |
623 | * @lnum: the last used logical eraseblock number for the PEB | |
624 | * @torture: if the physical eraseblock has to be tortured | |
625 | * | |
626 | */ | |
627 | static int do_sync_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, | |
628 | int vol_id, int lnum, int torture) | |
629 | { | |
1a31b20c | 630 | struct ubi_work wl_wrk; |
8199b901 RW |
631 | |
632 | dbg_wl("sync erase of PEB %i", e->pnum); | |
633 | ||
1a31b20c SS |
634 | wl_wrk.e = e; |
635 | wl_wrk.vol_id = vol_id; | |
636 | wl_wrk.lnum = lnum; | |
637 | wl_wrk.torture = torture; | |
8199b901 | 638 | |
1a31b20c | 639 | return __erase_worker(ubi, &wl_wrk); |
8199b901 RW |
640 | } |
641 | ||
34b89df9 | 642 | static int ensure_wear_leveling(struct ubi_device *ubi, int nested); |
801c135c AB |
643 | /** |
644 | * wear_leveling_worker - wear-leveling worker function. | |
645 | * @ubi: UBI device description object | |
646 | * @wrk: the work object | |
849271a4 RW |
647 | * @shutdown: non-zero if the worker has to free memory and exit |
648 | * because the WL-subsystem is shutting down | |
801c135c AB |
649 | * |
650 | * This function copies a more worn out physical eraseblock to a less worn out | |
651 | * one. Returns zero in case of success and a negative error code in case of | |
652 | * failure. | |
653 | */ | |
654 | static int wear_leveling_worker(struct ubi_device *ubi, struct ubi_work *wrk, | |
849271a4 | 655 | int shutdown) |
801c135c | 656 | { |
b86a2c56 | 657 | int err, scrubbing = 0, torture = 0, protect = 0, erroneous = 0; |
23654188 | 658 | int erase = 0, keep = 0, vol_id = -1, lnum = -1; |
8199b901 RW |
659 | #ifdef CONFIG_MTD_UBI_FASTMAP |
660 | int anchor = wrk->anchor; | |
661 | #endif | |
801c135c | 662 | struct ubi_wl_entry *e1, *e2; |
3291b52f | 663 | struct ubi_vid_io_buf *vidb; |
801c135c | 664 | struct ubi_vid_hdr *vid_hdr; |
34b89df9 | 665 | int dst_leb_clean = 0; |
801c135c AB |
666 | |
667 | kfree(wrk); | |
849271a4 | 668 | if (shutdown) |
801c135c AB |
669 | return 0; |
670 | ||
3291b52f BB |
671 | vidb = ubi_alloc_vid_buf(ubi, GFP_NOFS); |
672 | if (!vidb) | |
801c135c AB |
673 | return -ENOMEM; |
674 | ||
3291b52f BB |
675 | vid_hdr = ubi_get_vid_hdr(vidb); |
676 | ||
2e8f08de | 677 | down_read(&ubi->fm_eba_sem); |
43f9b25a | 678 | mutex_lock(&ubi->move_mutex); |
801c135c | 679 | spin_lock(&ubi->wl_lock); |
43f9b25a AB |
680 | ubi_assert(!ubi->move_from && !ubi->move_to); |
681 | ubi_assert(!ubi->move_to_put); | |
801c135c | 682 | |
43f9b25a | 683 | if (!ubi->free.rb_node || |
5abde384 | 684 | (!ubi->used.rb_node && !ubi->scrub.rb_node)) { |
801c135c | 685 | /* |
43f9b25a AB |
686 | * No free physical eraseblocks? Well, they must be waiting in |
687 | * the queue to be erased. Cancel movement - it will be | |
688 | * triggered again when a free physical eraseblock appears. | |
801c135c AB |
689 | * |
690 | * No used physical eraseblocks? They must be temporarily | |
691 | * protected from being moved. They will be moved to the | |
692 | * @ubi->used tree later and the wear-leveling will be | |
693 | * triggered again. | |
694 | */ | |
695 | dbg_wl("cancel WL, a list is empty: free %d, used %d", | |
5abde384 | 696 | !ubi->free.rb_node, !ubi->used.rb_node); |
43f9b25a | 697 | goto out_cancel; |
801c135c AB |
698 | } |
699 | ||
8199b901 RW |
700 | #ifdef CONFIG_MTD_UBI_FASTMAP |
701 | /* Check whether we need to produce an anchor PEB */ | |
702 | if (!anchor) | |
889027bc | 703 | anchor = !anchor_pebs_available(&ubi->free); |
8199b901 RW |
704 | |
705 | if (anchor) { | |
706 | e1 = find_anchor_wl_entry(&ubi->used); | |
707 | if (!e1) | |
708 | goto out_cancel; | |
709 | e2 = get_peb_for_wl(ubi); | |
710 | if (!e2) | |
711 | goto out_cancel; | |
712 | ||
713 | self_check_in_wl_tree(ubi, e1, &ubi->used); | |
714 | rb_erase(&e1->u.rb, &ubi->used); | |
715 | dbg_wl("anchor-move PEB %d to PEB %d", e1->pnum, e2->pnum); | |
716 | } else if (!ubi->scrub.rb_node) { | |
717 | #else | |
5abde384 | 718 | if (!ubi->scrub.rb_node) { |
8199b901 | 719 | #endif |
801c135c AB |
720 | /* |
721 | * Now pick the least worn-out used physical eraseblock and a | |
722 | * highly worn-out free physical eraseblock. If the erase | |
723 | * counters differ much enough, start wear-leveling. | |
724 | */ | |
23553b2c | 725 | e1 = rb_entry(rb_first(&ubi->used), struct ubi_wl_entry, u.rb); |
8199b901 RW |
726 | e2 = get_peb_for_wl(ubi); |
727 | if (!e2) | |
728 | goto out_cancel; | |
801c135c AB |
729 | |
730 | if (!(e2->ec - e1->ec >= UBI_WL_THRESHOLD)) { | |
731 | dbg_wl("no WL needed: min used EC %d, max free EC %d", | |
732 | e1->ec, e2->ec); | |
5ef4414f RW |
733 | |
734 | /* Give the unused PEB back */ | |
735 | wl_tree_add(e2, &ubi->free); | |
3d21bb76 | 736 | ubi->free_count++; |
43f9b25a | 737 | goto out_cancel; |
801c135c | 738 | } |
7bf523ae | 739 | self_check_in_wl_tree(ubi, e1, &ubi->used); |
23553b2c | 740 | rb_erase(&e1->u.rb, &ubi->used); |
801c135c AB |
741 | dbg_wl("move PEB %d EC %d to PEB %d EC %d", |
742 | e1->pnum, e1->ec, e2->pnum, e2->ec); | |
743 | } else { | |
43f9b25a AB |
744 | /* Perform scrubbing */ |
745 | scrubbing = 1; | |
23553b2c | 746 | e1 = rb_entry(rb_first(&ubi->scrub), struct ubi_wl_entry, u.rb); |
8199b901 RW |
747 | e2 = get_peb_for_wl(ubi); |
748 | if (!e2) | |
749 | goto out_cancel; | |
750 | ||
7bf523ae | 751 | self_check_in_wl_tree(ubi, e1, &ubi->scrub); |
23553b2c | 752 | rb_erase(&e1->u.rb, &ubi->scrub); |
801c135c AB |
753 | dbg_wl("scrub PEB %d to PEB %d", e1->pnum, e2->pnum); |
754 | } | |
755 | ||
801c135c AB |
756 | ubi->move_from = e1; |
757 | ubi->move_to = e2; | |
758 | spin_unlock(&ubi->wl_lock); | |
759 | ||
760 | /* | |
761 | * Now we are going to copy physical eraseblock @e1->pnum to @e2->pnum. | |
762 | * We so far do not know which logical eraseblock our physical | |
763 | * eraseblock (@e1) belongs to. We have to read the volume identifier | |
764 | * header first. | |
43f9b25a AB |
765 | * |
766 | * Note, we are protected from this PEB being unmapped and erased. The | |
767 | * 'ubi_wl_put_peb()' would wait for moving to be finished if the PEB | |
768 | * which is being moved was unmapped. | |
801c135c AB |
769 | */ |
770 | ||
3291b52f | 771 | err = ubi_io_read_vid_hdr(ubi, e1->pnum, vidb, 0); |
801c135c | 772 | if (err && err != UBI_IO_BITFLIPS) { |
34b89df9 | 773 | dst_leb_clean = 1; |
74d82d26 | 774 | if (err == UBI_IO_FF) { |
801c135c AB |
775 | /* |
776 | * We are trying to move PEB without a VID header. UBI | |
777 | * always write VID headers shortly after the PEB was | |
87960c0b AB |
778 | * given, so we have a situation when it has not yet |
779 | * had a chance to write it, because it was preempted. | |
780 | * So add this PEB to the protection queue so far, | |
815bc5f8 AB |
781 | * because presumably more data will be written there |
782 | * (including the missing VID header), and then we'll | |
87960c0b | 783 | * move it. |
801c135c AB |
784 | */ |
785 | dbg_wl("PEB %d has no VID header", e1->pnum); | |
87960c0b | 786 | protect = 1; |
43f9b25a | 787 | goto out_not_moved; |
92e1a7d9 AB |
788 | } else if (err == UBI_IO_FF_BITFLIPS) { |
789 | /* | |
790 | * The same situation as %UBI_IO_FF, but bit-flips were | |
791 | * detected. It is better to schedule this PEB for | |
792 | * scrubbing. | |
793 | */ | |
794 | dbg_wl("PEB %d has no VID header but has bit-flips", | |
795 | e1->pnum); | |
796 | scrubbing = 1; | |
797 | goto out_not_moved; | |
23654188 RW |
798 | } else if (ubi->fast_attach && err == UBI_IO_BAD_HDR_EBADMSG) { |
799 | /* | |
800 | * While a full scan would detect interrupted erasures | |
801 | * at attach time we can face them here when attached from | |
802 | * Fastmap. | |
803 | */ | |
804 | dbg_wl("PEB %d has ECC errors, maybe from an interrupted erasure", | |
805 | e1->pnum); | |
806 | erase = 1; | |
807 | goto out_not_moved; | |
801c135c | 808 | } |
43f9b25a | 809 | |
32608703 | 810 | ubi_err(ubi, "error %d while reading VID header from PEB %d", |
43f9b25a | 811 | err, e1->pnum); |
43f9b25a | 812 | goto out_error; |
801c135c AB |
813 | } |
814 | ||
9c259a52 AB |
815 | vol_id = be32_to_cpu(vid_hdr->vol_id); |
816 | lnum = be32_to_cpu(vid_hdr->lnum); | |
817 | ||
3291b52f | 818 | err = ubi_eba_copy_leb(ubi, e1->pnum, e2->pnum, vidb); |
801c135c | 819 | if (err) { |
87960c0b AB |
820 | if (err == MOVE_CANCEL_RACE) { |
821 | /* | |
822 | * The LEB has not been moved because the volume is | |
823 | * being deleted or the PEB has been put meanwhile. We | |
824 | * should prevent this PEB from being selected for | |
825 | * wear-leveling movement again, so put it to the | |
826 | * protection queue. | |
827 | */ | |
828 | protect = 1; | |
34b89df9 | 829 | dst_leb_clean = 1; |
87960c0b AB |
830 | goto out_not_moved; |
831 | } | |
e801e128 BP |
832 | if (err == MOVE_RETRY) { |
833 | scrubbing = 1; | |
34b89df9 | 834 | dst_leb_clean = 1; |
e801e128 BP |
835 | goto out_not_moved; |
836 | } | |
cc831464 | 837 | if (err == MOVE_TARGET_BITFLIPS || err == MOVE_TARGET_WR_ERR || |
b86a2c56 | 838 | err == MOVE_TARGET_RD_ERR) { |
9c259a52 AB |
839 | /* |
840 | * Target PEB had bit-flips or write error - torture it. | |
841 | */ | |
6fa6f5bb | 842 | torture = 1; |
23654188 | 843 | keep = 1; |
43f9b25a | 844 | goto out_not_moved; |
6fa6f5bb | 845 | } |
87960c0b | 846 | |
b86a2c56 AB |
847 | if (err == MOVE_SOURCE_RD_ERR) { |
848 | /* | |
849 | * An error happened while reading the source PEB. Do | |
850 | * not switch to R/O mode in this case, and give the | |
851 | * upper layers a possibility to recover from this, | |
852 | * e.g. by unmapping corresponding LEB. Instead, just | |
815bc5f8 AB |
853 | * put this PEB to the @ubi->erroneous list to prevent |
854 | * UBI from trying to move it over and over again. | |
b86a2c56 AB |
855 | */ |
856 | if (ubi->erroneous_peb_count > ubi->max_erroneous) { | |
32608703 | 857 | ubi_err(ubi, "too many erroneous eraseblocks (%d)", |
b86a2c56 AB |
858 | ubi->erroneous_peb_count); |
859 | goto out_error; | |
860 | } | |
34b89df9 | 861 | dst_leb_clean = 1; |
b86a2c56 AB |
862 | erroneous = 1; |
863 | goto out_not_moved; | |
864 | } | |
865 | ||
90bf0265 AB |
866 | if (err < 0) |
867 | goto out_error; | |
43f9b25a | 868 | |
87960c0b | 869 | ubi_assert(0); |
801c135c AB |
870 | } |
871 | ||
6a8f483f | 872 | /* The PEB has been successfully moved */ |
6a8f483f | 873 | if (scrubbing) |
32608703 | 874 | ubi_msg(ubi, "scrubbed PEB %d (LEB %d:%d), data moved to PEB %d", |
9c259a52 | 875 | e1->pnum, vol_id, lnum, e2->pnum); |
3291b52f | 876 | ubi_free_vid_buf(vidb); |
8c1e6ee1 | 877 | |
801c135c | 878 | spin_lock(&ubi->wl_lock); |
3c98b0a0 | 879 | if (!ubi->move_to_put) { |
5abde384 | 880 | wl_tree_add(e2, &ubi->used); |
3c98b0a0 AB |
881 | e2 = NULL; |
882 | } | |
801c135c | 883 | ubi->move_from = ubi->move_to = NULL; |
43f9b25a | 884 | ubi->move_to_put = ubi->wl_scheduled = 0; |
801c135c AB |
885 | spin_unlock(&ubi->wl_lock); |
886 | ||
8199b901 | 887 | err = do_sync_erase(ubi, e1, vol_id, lnum, 0); |
3c98b0a0 | 888 | if (err) { |
21d08bbc | 889 | if (e2) |
ee59ba8b | 890 | wl_entry_destroy(ubi, e2); |
87960c0b | 891 | goto out_ro; |
3c98b0a0 | 892 | } |
6a8f483f | 893 | |
3c98b0a0 | 894 | if (e2) { |
801c135c AB |
895 | /* |
896 | * Well, the target PEB was put meanwhile, schedule it for | |
897 | * erasure. | |
898 | */ | |
9c259a52 AB |
899 | dbg_wl("PEB %d (LEB %d:%d) was put meanwhile, erase", |
900 | e2->pnum, vol_id, lnum); | |
8199b901 | 901 | err = do_sync_erase(ubi, e2, vol_id, lnum, 0); |
aa5ad3b6 | 902 | if (err) |
87960c0b | 903 | goto out_ro; |
801c135c AB |
904 | } |
905 | ||
801c135c | 906 | dbg_wl("done"); |
43f9b25a | 907 | mutex_unlock(&ubi->move_mutex); |
2e8f08de | 908 | up_read(&ubi->fm_eba_sem); |
43f9b25a | 909 | return 0; |
801c135c AB |
910 | |
911 | /* | |
43f9b25a AB |
912 | * For some reasons the LEB was not moved, might be an error, might be |
913 | * something else. @e1 was not changed, so return it back. @e2 might | |
6fa6f5bb | 914 | * have been changed, schedule it for erasure. |
801c135c | 915 | */ |
43f9b25a | 916 | out_not_moved: |
9c259a52 AB |
917 | if (vol_id != -1) |
918 | dbg_wl("cancel moving PEB %d (LEB %d:%d) to PEB %d (%d)", | |
919 | e1->pnum, vol_id, lnum, e2->pnum, err); | |
920 | else | |
921 | dbg_wl("cancel moving PEB %d to PEB %d (%d)", | |
922 | e1->pnum, e2->pnum, err); | |
801c135c | 923 | spin_lock(&ubi->wl_lock); |
87960c0b AB |
924 | if (protect) |
925 | prot_queue_add(ubi, e1); | |
b86a2c56 AB |
926 | else if (erroneous) { |
927 | wl_tree_add(e1, &ubi->erroneous); | |
928 | ubi->erroneous_peb_count += 1; | |
929 | } else if (scrubbing) | |
43f9b25a | 930 | wl_tree_add(e1, &ubi->scrub); |
23654188 | 931 | else if (keep) |
5abde384 | 932 | wl_tree_add(e1, &ubi->used); |
34b89df9 SS |
933 | if (dst_leb_clean) { |
934 | wl_tree_add(e2, &ubi->free); | |
935 | ubi->free_count++; | |
936 | } | |
937 | ||
6fa6f5bb | 938 | ubi_assert(!ubi->move_to_put); |
801c135c | 939 | ubi->move_from = ubi->move_to = NULL; |
6fa6f5bb | 940 | ubi->wl_scheduled = 0; |
801c135c AB |
941 | spin_unlock(&ubi->wl_lock); |
942 | ||
3291b52f | 943 | ubi_free_vid_buf(vidb); |
34b89df9 SS |
944 | if (dst_leb_clean) { |
945 | ensure_wear_leveling(ubi, 1); | |
946 | } else { | |
947 | err = do_sync_erase(ubi, e2, vol_id, lnum, torture); | |
948 | if (err) | |
949 | goto out_ro; | |
950 | } | |
aa5ad3b6 | 951 | |
23654188 RW |
952 | if (erase) { |
953 | err = do_sync_erase(ubi, e1, vol_id, lnum, 1); | |
954 | if (err) | |
955 | goto out_ro; | |
956 | } | |
957 | ||
43f9b25a | 958 | mutex_unlock(&ubi->move_mutex); |
2e8f08de | 959 | up_read(&ubi->fm_eba_sem); |
43f9b25a AB |
960 | return 0; |
961 | ||
962 | out_error: | |
9c259a52 | 963 | if (vol_id != -1) |
32608703 | 964 | ubi_err(ubi, "error %d while moving PEB %d to PEB %d", |
9c259a52 AB |
965 | err, e1->pnum, e2->pnum); |
966 | else | |
32608703 | 967 | ubi_err(ubi, "error %d while moving PEB %d (LEB %d:%d) to PEB %d", |
9c259a52 | 968 | err, e1->pnum, vol_id, lnum, e2->pnum); |
43f9b25a AB |
969 | spin_lock(&ubi->wl_lock); |
970 | ubi->move_from = ubi->move_to = NULL; | |
971 | ubi->move_to_put = ubi->wl_scheduled = 0; | |
972 | spin_unlock(&ubi->wl_lock); | |
973 | ||
3291b52f | 974 | ubi_free_vid_buf(vidb); |
ee59ba8b RW |
975 | wl_entry_destroy(ubi, e1); |
976 | wl_entry_destroy(ubi, e2); | |
43f9b25a | 977 | |
87960c0b AB |
978 | out_ro: |
979 | ubi_ro_mode(ubi); | |
43f9b25a | 980 | mutex_unlock(&ubi->move_mutex); |
2e8f08de | 981 | up_read(&ubi->fm_eba_sem); |
87960c0b AB |
982 | ubi_assert(err != 0); |
983 | return err < 0 ? err : -EIO; | |
43f9b25a AB |
984 | |
985 | out_cancel: | |
986 | ubi->wl_scheduled = 0; | |
987 | spin_unlock(&ubi->wl_lock); | |
988 | mutex_unlock(&ubi->move_mutex); | |
2e8f08de | 989 | up_read(&ubi->fm_eba_sem); |
3291b52f | 990 | ubi_free_vid_buf(vidb); |
43f9b25a | 991 | return 0; |
801c135c AB |
992 | } |
993 | ||
994 | /** | |
995 | * ensure_wear_leveling - schedule wear-leveling if it is needed. | |
996 | * @ubi: UBI device description object | |
8199b901 | 997 | * @nested: set to non-zero if this function is called from UBI worker |
801c135c AB |
998 | * |
999 | * This function checks if it is time to start wear-leveling and schedules it | |
1000 | * if yes. This function returns zero in case of success and a negative error | |
1001 | * code in case of failure. | |
1002 | */ | |
8199b901 | 1003 | static int ensure_wear_leveling(struct ubi_device *ubi, int nested) |
801c135c AB |
1004 | { |
1005 | int err = 0; | |
1006 | struct ubi_wl_entry *e1; | |
1007 | struct ubi_wl_entry *e2; | |
1008 | struct ubi_work *wrk; | |
1009 | ||
1010 | spin_lock(&ubi->wl_lock); | |
1011 | if (ubi->wl_scheduled) | |
1012 | /* Wear-leveling is already in the work queue */ | |
1013 | goto out_unlock; | |
1014 | ||
1015 | /* | |
1016 | * If the ubi->scrub tree is not empty, scrubbing is needed, and the | |
1017 | * the WL worker has to be scheduled anyway. | |
1018 | */ | |
5abde384 AB |
1019 | if (!ubi->scrub.rb_node) { |
1020 | if (!ubi->used.rb_node || !ubi->free.rb_node) | |
801c135c AB |
1021 | /* No physical eraseblocks - no deal */ |
1022 | goto out_unlock; | |
1023 | ||
1024 | /* | |
1025 | * We schedule wear-leveling only if the difference between the | |
1026 | * lowest erase counter of used physical eraseblocks and a high | |
025dfdaf | 1027 | * erase counter of free physical eraseblocks is greater than |
801c135c AB |
1028 | * %UBI_WL_THRESHOLD. |
1029 | */ | |
23553b2c | 1030 | e1 = rb_entry(rb_first(&ubi->used), struct ubi_wl_entry, u.rb); |
8199b901 | 1031 | e2 = find_wl_entry(ubi, &ubi->free, WL_FREE_MAX_DIFF); |
801c135c AB |
1032 | |
1033 | if (!(e2->ec - e1->ec >= UBI_WL_THRESHOLD)) | |
1034 | goto out_unlock; | |
1035 | dbg_wl("schedule wear-leveling"); | |
1036 | } else | |
1037 | dbg_wl("schedule scrubbing"); | |
1038 | ||
1039 | ubi->wl_scheduled = 1; | |
1040 | spin_unlock(&ubi->wl_lock); | |
1041 | ||
33818bbb | 1042 | wrk = kmalloc(sizeof(struct ubi_work), GFP_NOFS); |
801c135c AB |
1043 | if (!wrk) { |
1044 | err = -ENOMEM; | |
1045 | goto out_cancel; | |
1046 | } | |
1047 | ||
8199b901 | 1048 | wrk->anchor = 0; |
801c135c | 1049 | wrk->func = &wear_leveling_worker; |
8199b901 RW |
1050 | if (nested) |
1051 | __schedule_ubi_work(ubi, wrk); | |
1052 | else | |
1053 | schedule_ubi_work(ubi, wrk); | |
801c135c AB |
1054 | return err; |
1055 | ||
1056 | out_cancel: | |
1057 | spin_lock(&ubi->wl_lock); | |
1058 | ubi->wl_scheduled = 0; | |
1059 | out_unlock: | |
1060 | spin_unlock(&ubi->wl_lock); | |
1061 | return err; | |
1062 | } | |
1063 | ||
1064 | /** | |
1a31b20c | 1065 | * __erase_worker - physical eraseblock erase worker function. |
801c135c AB |
1066 | * @ubi: UBI device description object |
1067 | * @wl_wrk: the work object | |
849271a4 RW |
1068 | * @shutdown: non-zero if the worker has to free memory and exit |
1069 | * because the WL sub-system is shutting down | |
801c135c AB |
1070 | * |
1071 | * This function erases a physical eraseblock and perform torture testing if | |
1072 | * needed. It also takes care about marking the physical eraseblock bad if | |
1073 | * needed. Returns zero in case of success and a negative error code in case of | |
1074 | * failure. | |
1075 | */ | |
1a31b20c | 1076 | static int __erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk) |
801c135c | 1077 | { |
801c135c | 1078 | struct ubi_wl_entry *e = wl_wrk->e; |
37f758a0 | 1079 | int pnum = e->pnum; |
d36e59e6 JR |
1080 | int vol_id = wl_wrk->vol_id; |
1081 | int lnum = wl_wrk->lnum; | |
37f758a0 | 1082 | int err, available_consumed = 0; |
801c135c | 1083 | |
d36e59e6 JR |
1084 | dbg_wl("erase PEB %d EC %d LEB %d:%d", |
1085 | pnum, e->ec, wl_wrk->vol_id, wl_wrk->lnum); | |
801c135c AB |
1086 | |
1087 | err = sync_erase(ubi, e, wl_wrk->torture); | |
1088 | if (!err) { | |
801c135c | 1089 | spin_lock(&ubi->wl_lock); |
5abde384 | 1090 | wl_tree_add(e, &ubi->free); |
8199b901 | 1091 | ubi->free_count++; |
801c135c AB |
1092 | spin_unlock(&ubi->wl_lock); |
1093 | ||
1094 | /* | |
9c9ec147 AB |
1095 | * One more erase operation has happened, take care about |
1096 | * protected physical eraseblocks. | |
801c135c | 1097 | */ |
7b6c32da | 1098 | serve_prot_queue(ubi); |
801c135c AB |
1099 | |
1100 | /* And take care about wear-leveling */ | |
8199b901 | 1101 | err = ensure_wear_leveling(ubi, 1); |
801c135c AB |
1102 | return err; |
1103 | } | |
1104 | ||
32608703 | 1105 | ubi_err(ubi, "failed to erase PEB %d, error %d", pnum, err); |
801c135c | 1106 | |
784c1454 AB |
1107 | if (err == -EINTR || err == -ENOMEM || err == -EAGAIN || |
1108 | err == -EBUSY) { | |
1109 | int err1; | |
1110 | ||
1111 | /* Re-schedule the LEB for erasure */ | |
2e8f08de | 1112 | err1 = schedule_erase(ubi, e, vol_id, lnum, 0, false); |
784c1454 | 1113 | if (err1) { |
6b238de1 | 1114 | wl_entry_destroy(ubi, e); |
784c1454 AB |
1115 | err = err1; |
1116 | goto out_ro; | |
1117 | } | |
1118 | return err; | |
e57e0d8e AB |
1119 | } |
1120 | ||
ee59ba8b | 1121 | wl_entry_destroy(ubi, e); |
e57e0d8e | 1122 | if (err != -EIO) |
801c135c AB |
1123 | /* |
1124 | * If this is not %-EIO, we have no idea what to do. Scheduling | |
1125 | * this physical eraseblock for erasure again would cause | |
815bc5f8 | 1126 | * errors again and again. Well, lets switch to R/O mode. |
801c135c | 1127 | */ |
784c1454 | 1128 | goto out_ro; |
801c135c AB |
1129 | |
1130 | /* It is %-EIO, the PEB went bad */ | |
1131 | ||
1132 | if (!ubi->bad_allowed) { | |
32608703 | 1133 | ubi_err(ubi, "bad physical eraseblock %d detected", pnum); |
784c1454 AB |
1134 | goto out_ro; |
1135 | } | |
801c135c | 1136 | |
784c1454 | 1137 | spin_lock(&ubi->volumes_lock); |
784c1454 | 1138 | if (ubi->beb_rsvd_pebs == 0) { |
37f758a0 SL |
1139 | if (ubi->avail_pebs == 0) { |
1140 | spin_unlock(&ubi->volumes_lock); | |
32608703 | 1141 | ubi_err(ubi, "no reserved/available physical eraseblocks"); |
37f758a0 SL |
1142 | goto out_ro; |
1143 | } | |
1144 | ubi->avail_pebs -= 1; | |
1145 | available_consumed = 1; | |
784c1454 | 1146 | } |
784c1454 | 1147 | spin_unlock(&ubi->volumes_lock); |
801c135c | 1148 | |
32608703 | 1149 | ubi_msg(ubi, "mark PEB %d as bad", pnum); |
784c1454 AB |
1150 | err = ubi_io_mark_bad(ubi, pnum); |
1151 | if (err) | |
1152 | goto out_ro; | |
1153 | ||
1154 | spin_lock(&ubi->volumes_lock); | |
37f758a0 SL |
1155 | if (ubi->beb_rsvd_pebs > 0) { |
1156 | if (available_consumed) { | |
1157 | /* | |
1158 | * The amount of reserved PEBs increased since we last | |
1159 | * checked. | |
1160 | */ | |
1161 | ubi->avail_pebs += 1; | |
1162 | available_consumed = 0; | |
1163 | } | |
1164 | ubi->beb_rsvd_pebs -= 1; | |
1165 | } | |
784c1454 AB |
1166 | ubi->bad_peb_count += 1; |
1167 | ubi->good_peb_count -= 1; | |
1168 | ubi_calculate_reserved(ubi); | |
37f758a0 | 1169 | if (available_consumed) |
32608703 | 1170 | ubi_warn(ubi, "no PEBs in the reserved pool, used an available PEB"); |
37f758a0 | 1171 | else if (ubi->beb_rsvd_pebs) |
32608703 TB |
1172 | ubi_msg(ubi, "%d PEBs left in the reserve", |
1173 | ubi->beb_rsvd_pebs); | |
52b605d1 | 1174 | else |
32608703 | 1175 | ubi_warn(ubi, "last PEB from the reserve was used"); |
784c1454 AB |
1176 | spin_unlock(&ubi->volumes_lock); |
1177 | ||
1178 | return err; | |
801c135c | 1179 | |
784c1454 | 1180 | out_ro: |
37f758a0 SL |
1181 | if (available_consumed) { |
1182 | spin_lock(&ubi->volumes_lock); | |
1183 | ubi->avail_pebs += 1; | |
1184 | spin_unlock(&ubi->volumes_lock); | |
1185 | } | |
784c1454 | 1186 | ubi_ro_mode(ubi); |
801c135c AB |
1187 | return err; |
1188 | } | |
1189 | ||
1a31b20c SS |
1190 | static int erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk, |
1191 | int shutdown) | |
1192 | { | |
1193 | int ret; | |
1194 | ||
1195 | if (shutdown) { | |
1196 | struct ubi_wl_entry *e = wl_wrk->e; | |
1197 | ||
1198 | dbg_wl("cancel erasure of PEB %d EC %d", e->pnum, e->ec); | |
1199 | kfree(wl_wrk); | |
1200 | wl_entry_destroy(ubi, e); | |
1201 | return 0; | |
1202 | } | |
1203 | ||
1204 | ret = __erase_worker(ubi, wl_wrk); | |
1205 | kfree(wl_wrk); | |
1206 | return ret; | |
1207 | } | |
1208 | ||
801c135c | 1209 | /** |
85c6e6e2 | 1210 | * ubi_wl_put_peb - return a PEB to the wear-leveling sub-system. |
801c135c | 1211 | * @ubi: UBI device description object |
d36e59e6 JR |
1212 | * @vol_id: the volume ID that last used this PEB |
1213 | * @lnum: the last used logical eraseblock number for the PEB | |
801c135c AB |
1214 | * @pnum: physical eraseblock to return |
1215 | * @torture: if this physical eraseblock has to be tortured | |
1216 | * | |
1217 | * This function is called to return physical eraseblock @pnum to the pool of | |
1218 | * free physical eraseblocks. The @torture flag has to be set if an I/O error | |
1219 | * occurred to this @pnum and it has to be tested. This function returns zero | |
43f9b25a | 1220 | * in case of success, and a negative error code in case of failure. |
801c135c | 1221 | */ |
d36e59e6 JR |
1222 | int ubi_wl_put_peb(struct ubi_device *ubi, int vol_id, int lnum, |
1223 | int pnum, int torture) | |
801c135c AB |
1224 | { |
1225 | int err; | |
1226 | struct ubi_wl_entry *e; | |
1227 | ||
1228 | dbg_wl("PEB %d", pnum); | |
1229 | ubi_assert(pnum >= 0); | |
1230 | ubi_assert(pnum < ubi->peb_count); | |
1231 | ||
111ab0b2 RW |
1232 | down_read(&ubi->fm_protect); |
1233 | ||
43f9b25a | 1234 | retry: |
801c135c | 1235 | spin_lock(&ubi->wl_lock); |
801c135c AB |
1236 | e = ubi->lookuptbl[pnum]; |
1237 | if (e == ubi->move_from) { | |
1238 | /* | |
1239 | * User is putting the physical eraseblock which was selected to | |
1240 | * be moved. It will be scheduled for erasure in the | |
1241 | * wear-leveling worker. | |
1242 | */ | |
43f9b25a | 1243 | dbg_wl("PEB %d is being moved, wait", pnum); |
801c135c | 1244 | spin_unlock(&ubi->wl_lock); |
43f9b25a AB |
1245 | |
1246 | /* Wait for the WL worker by taking the @ubi->move_mutex */ | |
1247 | mutex_lock(&ubi->move_mutex); | |
1248 | mutex_unlock(&ubi->move_mutex); | |
1249 | goto retry; | |
801c135c AB |
1250 | } else if (e == ubi->move_to) { |
1251 | /* | |
1252 | * User is putting the physical eraseblock which was selected | |
1253 | * as the target the data is moved to. It may happen if the EBA | |
85c6e6e2 AB |
1254 | * sub-system already re-mapped the LEB in 'ubi_eba_copy_leb()' |
1255 | * but the WL sub-system has not put the PEB to the "used" tree | |
1256 | * yet, but it is about to do this. So we just set a flag which | |
1257 | * will tell the WL worker that the PEB is not needed anymore | |
1258 | * and should be scheduled for erasure. | |
801c135c AB |
1259 | */ |
1260 | dbg_wl("PEB %d is the target of data moving", pnum); | |
1261 | ubi_assert(!ubi->move_to_put); | |
1262 | ubi->move_to_put = 1; | |
1263 | spin_unlock(&ubi->wl_lock); | |
111ab0b2 | 1264 | up_read(&ubi->fm_protect); |
801c135c AB |
1265 | return 0; |
1266 | } else { | |
5abde384 | 1267 | if (in_wl_tree(e, &ubi->used)) { |
7bf523ae | 1268 | self_check_in_wl_tree(ubi, e, &ubi->used); |
23553b2c | 1269 | rb_erase(&e->u.rb, &ubi->used); |
5abde384 | 1270 | } else if (in_wl_tree(e, &ubi->scrub)) { |
7bf523ae | 1271 | self_check_in_wl_tree(ubi, e, &ubi->scrub); |
23553b2c | 1272 | rb_erase(&e->u.rb, &ubi->scrub); |
b86a2c56 | 1273 | } else if (in_wl_tree(e, &ubi->erroneous)) { |
7bf523ae | 1274 | self_check_in_wl_tree(ubi, e, &ubi->erroneous); |
b86a2c56 AB |
1275 | rb_erase(&e->u.rb, &ubi->erroneous); |
1276 | ubi->erroneous_peb_count -= 1; | |
1277 | ubi_assert(ubi->erroneous_peb_count >= 0); | |
815bc5f8 | 1278 | /* Erroneous PEBs should be tortured */ |
b86a2c56 | 1279 | torture = 1; |
43f9b25a | 1280 | } else { |
7b6c32da | 1281 | err = prot_queue_del(ubi, e->pnum); |
43f9b25a | 1282 | if (err) { |
32608703 | 1283 | ubi_err(ubi, "PEB %d not found", pnum); |
43f9b25a AB |
1284 | ubi_ro_mode(ubi); |
1285 | spin_unlock(&ubi->wl_lock); | |
111ab0b2 | 1286 | up_read(&ubi->fm_protect); |
43f9b25a AB |
1287 | return err; |
1288 | } | |
1289 | } | |
801c135c AB |
1290 | } |
1291 | spin_unlock(&ubi->wl_lock); | |
1292 | ||
2e8f08de | 1293 | err = schedule_erase(ubi, e, vol_id, lnum, torture, false); |
801c135c AB |
1294 | if (err) { |
1295 | spin_lock(&ubi->wl_lock); | |
5abde384 | 1296 | wl_tree_add(e, &ubi->used); |
801c135c AB |
1297 | spin_unlock(&ubi->wl_lock); |
1298 | } | |
1299 | ||
111ab0b2 | 1300 | up_read(&ubi->fm_protect); |
801c135c AB |
1301 | return err; |
1302 | } | |
1303 | ||
1304 | /** | |
1305 | * ubi_wl_scrub_peb - schedule a physical eraseblock for scrubbing. | |
1306 | * @ubi: UBI device description object | |
1307 | * @pnum: the physical eraseblock to schedule | |
1308 | * | |
1309 | * If a bit-flip in a physical eraseblock is detected, this physical eraseblock | |
1310 | * needs scrubbing. This function schedules a physical eraseblock for | |
1311 | * scrubbing which is done in background. This function returns zero in case of | |
1312 | * success and a negative error code in case of failure. | |
1313 | */ | |
1314 | int ubi_wl_scrub_peb(struct ubi_device *ubi, int pnum) | |
1315 | { | |
1316 | struct ubi_wl_entry *e; | |
1317 | ||
32608703 | 1318 | ubi_msg(ubi, "schedule PEB %d for scrubbing", pnum); |
801c135c AB |
1319 | |
1320 | retry: | |
1321 | spin_lock(&ubi->wl_lock); | |
1322 | e = ubi->lookuptbl[pnum]; | |
d3f6e6c6 AB |
1323 | if (e == ubi->move_from || in_wl_tree(e, &ubi->scrub) || |
1324 | in_wl_tree(e, &ubi->erroneous)) { | |
801c135c AB |
1325 | spin_unlock(&ubi->wl_lock); |
1326 | return 0; | |
1327 | } | |
1328 | ||
1329 | if (e == ubi->move_to) { | |
1330 | /* | |
1331 | * This physical eraseblock was used to move data to. The data | |
1332 | * was moved but the PEB was not yet inserted to the proper | |
1333 | * tree. We should just wait a little and let the WL worker | |
1334 | * proceed. | |
1335 | */ | |
1336 | spin_unlock(&ubi->wl_lock); | |
1337 | dbg_wl("the PEB %d is not in proper tree, retry", pnum); | |
1338 | yield(); | |
1339 | goto retry; | |
1340 | } | |
1341 | ||
5abde384 | 1342 | if (in_wl_tree(e, &ubi->used)) { |
7bf523ae | 1343 | self_check_in_wl_tree(ubi, e, &ubi->used); |
23553b2c | 1344 | rb_erase(&e->u.rb, &ubi->used); |
43f9b25a AB |
1345 | } else { |
1346 | int err; | |
1347 | ||
7b6c32da | 1348 | err = prot_queue_del(ubi, e->pnum); |
43f9b25a | 1349 | if (err) { |
32608703 | 1350 | ubi_err(ubi, "PEB %d not found", pnum); |
43f9b25a AB |
1351 | ubi_ro_mode(ubi); |
1352 | spin_unlock(&ubi->wl_lock); | |
1353 | return err; | |
1354 | } | |
1355 | } | |
801c135c | 1356 | |
5abde384 | 1357 | wl_tree_add(e, &ubi->scrub); |
801c135c AB |
1358 | spin_unlock(&ubi->wl_lock); |
1359 | ||
1360 | /* | |
1361 | * Technically scrubbing is the same as wear-leveling, so it is done | |
1362 | * by the WL worker. | |
1363 | */ | |
8199b901 | 1364 | return ensure_wear_leveling(ubi, 0); |
801c135c AB |
1365 | } |
1366 | ||
1367 | /** | |
1368 | * ubi_wl_flush - flush all pending works. | |
1369 | * @ubi: UBI device description object | |
62f38455 JR |
1370 | * @vol_id: the volume id to flush for |
1371 | * @lnum: the logical eraseblock number to flush for | |
801c135c | 1372 | * |
62f38455 JR |
1373 | * This function executes all pending works for a particular volume id / |
1374 | * logical eraseblock number pair. If either value is set to %UBI_ALL, then it | |
1375 | * acts as a wildcard for all of the corresponding volume numbers or logical | |
1376 | * eraseblock numbers. It returns zero in case of success and a negative error | |
1377 | * code in case of failure. | |
801c135c | 1378 | */ |
62f38455 | 1379 | int ubi_wl_flush(struct ubi_device *ubi, int vol_id, int lnum) |
801c135c | 1380 | { |
62f38455 JR |
1381 | int err = 0; |
1382 | int found = 1; | |
801c135c AB |
1383 | |
1384 | /* | |
7b6c32da | 1385 | * Erase while the pending works queue is not empty, but not more than |
801c135c AB |
1386 | * the number of currently pending works. |
1387 | */ | |
62f38455 JR |
1388 | dbg_wl("flush pending work for LEB %d:%d (%d pending works)", |
1389 | vol_id, lnum, ubi->works_count); | |
593dd33c | 1390 | |
62f38455 | 1391 | while (found) { |
49e236bc | 1392 | struct ubi_work *wrk, *tmp; |
62f38455 | 1393 | found = 0; |
593dd33c | 1394 | |
12027f1b | 1395 | down_read(&ubi->work_sem); |
62f38455 | 1396 | spin_lock(&ubi->wl_lock); |
49e236bc | 1397 | list_for_each_entry_safe(wrk, tmp, &ubi->works, list) { |
62f38455 JR |
1398 | if ((vol_id == UBI_ALL || wrk->vol_id == vol_id) && |
1399 | (lnum == UBI_ALL || wrk->lnum == lnum)) { | |
1400 | list_del(&wrk->list); | |
1401 | ubi->works_count -= 1; | |
1402 | ubi_assert(ubi->works_count >= 0); | |
1403 | spin_unlock(&ubi->wl_lock); | |
1404 | ||
1405 | err = wrk->func(ubi, wrk, 0); | |
12027f1b AB |
1406 | if (err) { |
1407 | up_read(&ubi->work_sem); | |
1408 | return err; | |
1409 | } | |
1410 | ||
62f38455 JR |
1411 | spin_lock(&ubi->wl_lock); |
1412 | found = 1; | |
1413 | break; | |
1414 | } | |
1415 | } | |
1416 | spin_unlock(&ubi->wl_lock); | |
12027f1b | 1417 | up_read(&ubi->work_sem); |
801c135c AB |
1418 | } |
1419 | ||
12027f1b AB |
1420 | /* |
1421 | * Make sure all the works which have been done in parallel are | |
1422 | * finished. | |
1423 | */ | |
1424 | down_write(&ubi->work_sem); | |
62f38455 | 1425 | up_write(&ubi->work_sem); |
12027f1b | 1426 | |
62f38455 | 1427 | return err; |
801c135c AB |
1428 | } |
1429 | ||
663586c0 RW |
1430 | static bool scrub_possible(struct ubi_device *ubi, struct ubi_wl_entry *e) |
1431 | { | |
1432 | if (in_wl_tree(e, &ubi->scrub)) | |
1433 | return false; | |
1434 | else if (in_wl_tree(e, &ubi->erroneous)) | |
1435 | return false; | |
1436 | else if (ubi->move_from == e) | |
1437 | return false; | |
1438 | else if (ubi->move_to == e) | |
1439 | return false; | |
1440 | ||
1441 | return true; | |
1442 | } | |
1443 | ||
1444 | /** | |
1445 | * ubi_bitflip_check - Check an eraseblock for bitflips and scrub it if needed. | |
1446 | * @ubi: UBI device description object | |
1447 | * @pnum: the physical eraseblock to schedule | |
1448 | * @force: dont't read the block, assume bitflips happened and take action. | |
1449 | * | |
1450 | * This function reads the given eraseblock and checks if bitflips occured. | |
1451 | * In case of bitflips, the eraseblock is scheduled for scrubbing. | |
1452 | * If scrubbing is forced with @force, the eraseblock is not read, | |
1453 | * but scheduled for scrubbing right away. | |
1454 | * | |
1455 | * Returns: | |
1456 | * %EINVAL, PEB is out of range | |
1457 | * %ENOENT, PEB is no longer used by UBI | |
1458 | * %EBUSY, PEB cannot be checked now or a check is currently running on it | |
1459 | * %EAGAIN, bit flips happened but scrubbing is currently not possible | |
1460 | * %EUCLEAN, bit flips happened and PEB is scheduled for scrubbing | |
1461 | * %0, no bit flips detected | |
1462 | */ | |
1463 | int ubi_bitflip_check(struct ubi_device *ubi, int pnum, int force) | |
1464 | { | |
04d37e5a | 1465 | int err = 0; |
663586c0 RW |
1466 | struct ubi_wl_entry *e; |
1467 | ||
1468 | if (pnum < 0 || pnum >= ubi->peb_count) { | |
1469 | err = -EINVAL; | |
1470 | goto out; | |
1471 | } | |
1472 | ||
1473 | /* | |
1474 | * Pause all parallel work, otherwise it can happen that the | |
1475 | * erase worker frees a wl entry under us. | |
1476 | */ | |
1477 | down_write(&ubi->work_sem); | |
1478 | ||
1479 | /* | |
1480 | * Make sure that the wl entry does not change state while | |
1481 | * inspecting it. | |
1482 | */ | |
1483 | spin_lock(&ubi->wl_lock); | |
1484 | e = ubi->lookuptbl[pnum]; | |
1485 | if (!e) { | |
1486 | spin_unlock(&ubi->wl_lock); | |
1487 | err = -ENOENT; | |
1488 | goto out_resume; | |
1489 | } | |
1490 | ||
1491 | /* | |
1492 | * Does it make sense to check this PEB? | |
1493 | */ | |
1494 | if (!scrub_possible(ubi, e)) { | |
1495 | spin_unlock(&ubi->wl_lock); | |
1496 | err = -EBUSY; | |
1497 | goto out_resume; | |
1498 | } | |
1499 | spin_unlock(&ubi->wl_lock); | |
1500 | ||
1501 | if (!force) { | |
1502 | mutex_lock(&ubi->buf_mutex); | |
1503 | err = ubi_io_read(ubi, ubi->peb_buf, pnum, 0, ubi->peb_size); | |
1504 | mutex_unlock(&ubi->buf_mutex); | |
1505 | } | |
1506 | ||
5578e48e | 1507 | if (force || err == UBI_IO_BITFLIPS) { |
663586c0 RW |
1508 | /* |
1509 | * Okay, bit flip happened, let's figure out what we can do. | |
1510 | */ | |
1511 | spin_lock(&ubi->wl_lock); | |
1512 | ||
1513 | /* | |
1514 | * Recheck. We released wl_lock, UBI might have killed the | |
1515 | * wl entry under us. | |
1516 | */ | |
1517 | e = ubi->lookuptbl[pnum]; | |
1518 | if (!e) { | |
1519 | spin_unlock(&ubi->wl_lock); | |
1520 | err = -ENOENT; | |
1521 | goto out_resume; | |
1522 | } | |
1523 | ||
1524 | /* | |
1525 | * Need to re-check state | |
1526 | */ | |
1527 | if (!scrub_possible(ubi, e)) { | |
1528 | spin_unlock(&ubi->wl_lock); | |
1529 | err = -EBUSY; | |
1530 | goto out_resume; | |
1531 | } | |
1532 | ||
1533 | if (in_pq(ubi, e)) { | |
1534 | prot_queue_del(ubi, e->pnum); | |
1535 | wl_tree_add(e, &ubi->scrub); | |
1536 | spin_unlock(&ubi->wl_lock); | |
1537 | ||
1538 | err = ensure_wear_leveling(ubi, 1); | |
1539 | } else if (in_wl_tree(e, &ubi->used)) { | |
1540 | rb_erase(&e->u.rb, &ubi->used); | |
1541 | wl_tree_add(e, &ubi->scrub); | |
1542 | spin_unlock(&ubi->wl_lock); | |
1543 | ||
1544 | err = ensure_wear_leveling(ubi, 1); | |
1545 | } else if (in_wl_tree(e, &ubi->free)) { | |
1546 | rb_erase(&e->u.rb, &ubi->free); | |
1547 | ubi->free_count--; | |
1548 | spin_unlock(&ubi->wl_lock); | |
1549 | ||
1550 | /* | |
1551 | * This PEB is empty we can schedule it for | |
1552 | * erasure right away. No wear leveling needed. | |
1553 | */ | |
1554 | err = schedule_erase(ubi, e, UBI_UNKNOWN, UBI_UNKNOWN, | |
1555 | force ? 0 : 1, true); | |
1556 | } else { | |
1557 | spin_unlock(&ubi->wl_lock); | |
1558 | err = -EAGAIN; | |
1559 | } | |
1560 | ||
1561 | if (!err && !force) | |
1562 | err = -EUCLEAN; | |
1563 | } else { | |
1564 | err = 0; | |
1565 | } | |
1566 | ||
1567 | out_resume: | |
1568 | up_write(&ubi->work_sem); | |
1569 | out: | |
1570 | ||
1571 | return err; | |
1572 | } | |
1573 | ||
801c135c AB |
1574 | /** |
1575 | * tree_destroy - destroy an RB-tree. | |
ee59ba8b | 1576 | * @ubi: UBI device description object |
801c135c AB |
1577 | * @root: the root of the tree to destroy |
1578 | */ | |
ee59ba8b | 1579 | static void tree_destroy(struct ubi_device *ubi, struct rb_root *root) |
801c135c AB |
1580 | { |
1581 | struct rb_node *rb; | |
1582 | struct ubi_wl_entry *e; | |
1583 | ||
1584 | rb = root->rb_node; | |
1585 | while (rb) { | |
1586 | if (rb->rb_left) | |
1587 | rb = rb->rb_left; | |
1588 | else if (rb->rb_right) | |
1589 | rb = rb->rb_right; | |
1590 | else { | |
23553b2c | 1591 | e = rb_entry(rb, struct ubi_wl_entry, u.rb); |
801c135c AB |
1592 | |
1593 | rb = rb_parent(rb); | |
1594 | if (rb) { | |
23553b2c | 1595 | if (rb->rb_left == &e->u.rb) |
801c135c AB |
1596 | rb->rb_left = NULL; |
1597 | else | |
1598 | rb->rb_right = NULL; | |
1599 | } | |
1600 | ||
ee59ba8b | 1601 | wl_entry_destroy(ubi, e); |
801c135c AB |
1602 | } |
1603 | } | |
1604 | } | |
1605 | ||
1606 | /** | |
1607 | * ubi_thread - UBI background thread. | |
1608 | * @u: the UBI device description object pointer | |
1609 | */ | |
cdfa788a | 1610 | int ubi_thread(void *u) |
801c135c AB |
1611 | { |
1612 | int failures = 0; | |
1613 | struct ubi_device *ubi = u; | |
1614 | ||
32608703 | 1615 | ubi_msg(ubi, "background thread \"%s\" started, PID %d", |
ba25f9dc | 1616 | ubi->bgt_name, task_pid_nr(current)); |
801c135c | 1617 | |
83144186 | 1618 | set_freezable(); |
801c135c AB |
1619 | for (;;) { |
1620 | int err; | |
1621 | ||
45fc5c81 | 1622 | if (kthread_should_stop()) |
cadb40cc | 1623 | break; |
801c135c AB |
1624 | |
1625 | if (try_to_freeze()) | |
1626 | continue; | |
1627 | ||
1628 | spin_lock(&ubi->wl_lock); | |
1629 | if (list_empty(&ubi->works) || ubi->ro_mode || | |
27a0f2a3 | 1630 | !ubi->thread_enabled || ubi_dbg_is_bgt_disabled(ubi)) { |
801c135c AB |
1631 | set_current_state(TASK_INTERRUPTIBLE); |
1632 | spin_unlock(&ubi->wl_lock); | |
1633 | schedule(); | |
1634 | continue; | |
1635 | } | |
1636 | spin_unlock(&ubi->wl_lock); | |
1637 | ||
1638 | err = do_work(ubi); | |
1639 | if (err) { | |
32608703 | 1640 | ubi_err(ubi, "%s: work failed with error code %d", |
801c135c AB |
1641 | ubi->bgt_name, err); |
1642 | if (failures++ > WL_MAX_FAILURES) { | |
1643 | /* | |
1644 | * Too many failures, disable the thread and | |
1645 | * switch to read-only mode. | |
1646 | */ | |
32608703 | 1647 | ubi_msg(ubi, "%s: %d consecutive failures", |
801c135c AB |
1648 | ubi->bgt_name, WL_MAX_FAILURES); |
1649 | ubi_ro_mode(ubi); | |
2ad49887 VG |
1650 | ubi->thread_enabled = 0; |
1651 | continue; | |
801c135c AB |
1652 | } |
1653 | } else | |
1654 | failures = 0; | |
1655 | ||
1656 | cond_resched(); | |
1657 | } | |
1658 | ||
801c135c | 1659 | dbg_wl("background thread \"%s\" is killed", ubi->bgt_name); |
6e7d8016 | 1660 | ubi->thread_enabled = 0; |
801c135c AB |
1661 | return 0; |
1662 | } | |
1663 | ||
1664 | /** | |
849271a4 | 1665 | * shutdown_work - shutdown all pending works. |
801c135c AB |
1666 | * @ubi: UBI device description object |
1667 | */ | |
849271a4 | 1668 | static void shutdown_work(struct ubi_device *ubi) |
801c135c AB |
1669 | { |
1670 | while (!list_empty(&ubi->works)) { | |
1671 | struct ubi_work *wrk; | |
1672 | ||
1673 | wrk = list_entry(ubi->works.next, struct ubi_work, list); | |
1674 | list_del(&wrk->list); | |
1675 | wrk->func(ubi, wrk, 1); | |
1676 | ubi->works_count -= 1; | |
1677 | ubi_assert(ubi->works_count >= 0); | |
1678 | } | |
1679 | } | |
1680 | ||
f78e5623 SH |
1681 | /** |
1682 | * erase_aeb - erase a PEB given in UBI attach info PEB | |
1683 | * @ubi: UBI device description object | |
1684 | * @aeb: UBI attach info PEB | |
1685 | * @sync: If true, erase synchronously. Otherwise schedule for erasure | |
1686 | */ | |
1687 | static int erase_aeb(struct ubi_device *ubi, struct ubi_ainf_peb *aeb, bool sync) | |
1688 | { | |
1689 | struct ubi_wl_entry *e; | |
1690 | int err; | |
1691 | ||
1692 | e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL); | |
1693 | if (!e) | |
1694 | return -ENOMEM; | |
1695 | ||
1696 | e->pnum = aeb->pnum; | |
1697 | e->ec = aeb->ec; | |
1698 | ubi->lookuptbl[e->pnum] = e; | |
1699 | ||
1700 | if (sync) { | |
1701 | err = sync_erase(ubi, e, false); | |
1702 | if (err) | |
1703 | goto out_free; | |
1704 | ||
1705 | wl_tree_add(e, &ubi->free); | |
1706 | ubi->free_count++; | |
1707 | } else { | |
1708 | err = schedule_erase(ubi, e, aeb->vol_id, aeb->lnum, 0, false); | |
1709 | if (err) | |
1710 | goto out_free; | |
1711 | } | |
1712 | ||
1713 | return 0; | |
1714 | ||
1715 | out_free: | |
1716 | wl_entry_destroy(ubi, e); | |
1717 | ||
1718 | return err; | |
1719 | } | |
1720 | ||
801c135c | 1721 | /** |
41e0cd9d | 1722 | * ubi_wl_init - initialize the WL sub-system using attaching information. |
801c135c | 1723 | * @ubi: UBI device description object |
a4e6042f | 1724 | * @ai: attaching information |
801c135c AB |
1725 | * |
1726 | * This function returns zero in case of success, and a negative error code in | |
1727 | * case of failure. | |
1728 | */ | |
41e0cd9d | 1729 | int ubi_wl_init(struct ubi_device *ubi, struct ubi_attach_info *ai) |
801c135c | 1730 | { |
8199b901 | 1731 | int err, i, reserved_pebs, found_pebs = 0; |
801c135c | 1732 | struct rb_node *rb1, *rb2; |
517af48c | 1733 | struct ubi_ainf_volume *av; |
2c5ec5ce | 1734 | struct ubi_ainf_peb *aeb, *tmp; |
801c135c AB |
1735 | struct ubi_wl_entry *e; |
1736 | ||
b86a2c56 | 1737 | ubi->used = ubi->erroneous = ubi->free = ubi->scrub = RB_ROOT; |
801c135c | 1738 | spin_lock_init(&ubi->wl_lock); |
43f9b25a | 1739 | mutex_init(&ubi->move_mutex); |
593dd33c | 1740 | init_rwsem(&ubi->work_sem); |
a4e6042f | 1741 | ubi->max_ec = ai->max_ec; |
801c135c AB |
1742 | INIT_LIST_HEAD(&ubi->works); |
1743 | ||
1744 | sprintf(ubi->bgt_name, UBI_BGT_NAME_PATTERN, ubi->ubi_num); | |
1745 | ||
801c135c | 1746 | err = -ENOMEM; |
6396bb22 | 1747 | ubi->lookuptbl = kcalloc(ubi->peb_count, sizeof(void *), GFP_KERNEL); |
801c135c | 1748 | if (!ubi->lookuptbl) |
cdfa788a | 1749 | return err; |
801c135c | 1750 | |
7b6c32da XX |
1751 | for (i = 0; i < UBI_PROT_QUEUE_LEN; i++) |
1752 | INIT_LIST_HEAD(&ubi->pq[i]); | |
1753 | ubi->pq_head = 0; | |
1754 | ||
73b0cd57 | 1755 | ubi->free_count = 0; |
a4e6042f | 1756 | list_for_each_entry_safe(aeb, tmp, &ai->erase, u.list) { |
801c135c AB |
1757 | cond_resched(); |
1758 | ||
f78e5623 SH |
1759 | err = erase_aeb(ubi, aeb, false); |
1760 | if (err) | |
801c135c AB |
1761 | goto out_free; |
1762 | ||
8199b901 | 1763 | found_pebs++; |
801c135c AB |
1764 | } |
1765 | ||
a4e6042f | 1766 | list_for_each_entry(aeb, &ai->free, u.list) { |
801c135c AB |
1767 | cond_resched(); |
1768 | ||
06b68ba1 | 1769 | e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL); |
7233982a WY |
1770 | if (!e) { |
1771 | err = -ENOMEM; | |
801c135c | 1772 | goto out_free; |
7233982a | 1773 | } |
801c135c | 1774 | |
2c5ec5ce AB |
1775 | e->pnum = aeb->pnum; |
1776 | e->ec = aeb->ec; | |
801c135c | 1777 | ubi_assert(e->ec >= 0); |
8199b901 | 1778 | |
5abde384 | 1779 | wl_tree_add(e, &ubi->free); |
8199b901 RW |
1780 | ubi->free_count++; |
1781 | ||
801c135c | 1782 | ubi->lookuptbl[e->pnum] = e; |
8199b901 RW |
1783 | |
1784 | found_pebs++; | |
801c135c AB |
1785 | } |
1786 | ||
517af48c AB |
1787 | ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb) { |
1788 | ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb) { | |
801c135c AB |
1789 | cond_resched(); |
1790 | ||
06b68ba1 | 1791 | e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL); |
7233982a WY |
1792 | if (!e) { |
1793 | err = -ENOMEM; | |
801c135c | 1794 | goto out_free; |
7233982a | 1795 | } |
801c135c | 1796 | |
2c5ec5ce AB |
1797 | e->pnum = aeb->pnum; |
1798 | e->ec = aeb->ec; | |
801c135c | 1799 | ubi->lookuptbl[e->pnum] = e; |
8199b901 | 1800 | |
2c5ec5ce | 1801 | if (!aeb->scrub) { |
801c135c AB |
1802 | dbg_wl("add PEB %d EC %d to the used tree", |
1803 | e->pnum, e->ec); | |
5abde384 | 1804 | wl_tree_add(e, &ubi->used); |
801c135c AB |
1805 | } else { |
1806 | dbg_wl("add PEB %d EC %d to the scrub tree", | |
1807 | e->pnum, e->ec); | |
5abde384 | 1808 | wl_tree_add(e, &ubi->scrub); |
801c135c | 1809 | } |
8199b901 RW |
1810 | |
1811 | found_pebs++; | |
801c135c AB |
1812 | } |
1813 | } | |
1814 | ||
fdf10ed7 RW |
1815 | list_for_each_entry(aeb, &ai->fastmap, u.list) { |
1816 | cond_resched(); | |
1817 | ||
1818 | e = ubi_find_fm_block(ubi, aeb->pnum); | |
8199b901 | 1819 | |
fdf10ed7 RW |
1820 | if (e) { |
1821 | ubi_assert(!ubi->lookuptbl[e->pnum]); | |
1822 | ubi->lookuptbl[e->pnum] = e; | |
1823 | } else { | |
f78e5623 SH |
1824 | bool sync = false; |
1825 | ||
fdf10ed7 RW |
1826 | /* |
1827 | * Usually old Fastmap PEBs are scheduled for erasure | |
1828 | * and we don't have to care about them but if we face | |
1829 | * an power cut before scheduling them we need to | |
1830 | * take care of them here. | |
1831 | */ | |
1832 | if (ubi->lookuptbl[aeb->pnum]) | |
1833 | continue; | |
1834 | ||
f78e5623 SH |
1835 | /* |
1836 | * The fastmap update code might not find a free PEB for | |
1837 | * writing the fastmap anchor to and then reuses the | |
1838 | * current fastmap anchor PEB. When this PEB gets erased | |
1839 | * and a power cut happens before it is written again we | |
1840 | * must make sure that the fastmap attach code doesn't | |
1841 | * find any outdated fastmap anchors, hence we erase the | |
1842 | * outdated fastmap anchor PEBs synchronously here. | |
1843 | */ | |
1844 | if (aeb->vol_id == UBI_FM_SB_VOLUME_ID) | |
1845 | sync = true; | |
68303564 | 1846 | |
f78e5623 SH |
1847 | err = erase_aeb(ubi, aeb, sync); |
1848 | if (err) | |
fdf10ed7 | 1849 | goto out_free; |
68303564 | 1850 | } |
fdf10ed7 RW |
1851 | |
1852 | found_pebs++; | |
68303564 | 1853 | } |
fdf10ed7 RW |
1854 | |
1855 | dbg_wl("found %i PEBs", found_pebs); | |
1856 | ||
1857 | ubi_assert(ubi->good_peb_count == found_pebs); | |
8199b901 RW |
1858 | |
1859 | reserved_pebs = WL_RESERVED_PEBS; | |
acfda79f | 1860 | ubi_fastmap_init(ubi, &reserved_pebs); |
8199b901 RW |
1861 | |
1862 | if (ubi->avail_pebs < reserved_pebs) { | |
32608703 | 1863 | ubi_err(ubi, "no enough physical eraseblocks (%d, need %d)", |
8199b901 | 1864 | ubi->avail_pebs, reserved_pebs); |
5fc01ab6 | 1865 | if (ubi->corr_peb_count) |
32608703 | 1866 | ubi_err(ubi, "%d PEBs are corrupted and not used", |
5fc01ab6 | 1867 | ubi->corr_peb_count); |
7c7feb2e | 1868 | err = -ENOSPC; |
801c135c AB |
1869 | goto out_free; |
1870 | } | |
8199b901 RW |
1871 | ubi->avail_pebs -= reserved_pebs; |
1872 | ubi->rsvd_pebs += reserved_pebs; | |
801c135c AB |
1873 | |
1874 | /* Schedule wear-leveling if needed */ | |
8199b901 | 1875 | err = ensure_wear_leveling(ubi, 0); |
801c135c AB |
1876 | if (err) |
1877 | goto out_free; | |
1878 | ||
1879 | return 0; | |
1880 | ||
1881 | out_free: | |
849271a4 | 1882 | shutdown_work(ubi); |
ee59ba8b RW |
1883 | tree_destroy(ubi, &ubi->used); |
1884 | tree_destroy(ubi, &ubi->free); | |
1885 | tree_destroy(ubi, &ubi->scrub); | |
801c135c | 1886 | kfree(ubi->lookuptbl); |
801c135c AB |
1887 | return err; |
1888 | } | |
1889 | ||
1890 | /** | |
7b6c32da | 1891 | * protection_queue_destroy - destroy the protection queue. |
801c135c AB |
1892 | * @ubi: UBI device description object |
1893 | */ | |
7b6c32da | 1894 | static void protection_queue_destroy(struct ubi_device *ubi) |
801c135c | 1895 | { |
7b6c32da XX |
1896 | int i; |
1897 | struct ubi_wl_entry *e, *tmp; | |
801c135c | 1898 | |
7b6c32da XX |
1899 | for (i = 0; i < UBI_PROT_QUEUE_LEN; ++i) { |
1900 | list_for_each_entry_safe(e, tmp, &ubi->pq[i], u.list) { | |
1901 | list_del(&e->u.list); | |
ee59ba8b | 1902 | wl_entry_destroy(ubi, e); |
801c135c AB |
1903 | } |
1904 | } | |
1905 | } | |
1906 | ||
1907 | /** | |
85c6e6e2 | 1908 | * ubi_wl_close - close the wear-leveling sub-system. |
801c135c AB |
1909 | * @ubi: UBI device description object |
1910 | */ | |
1911 | void ubi_wl_close(struct ubi_device *ubi) | |
1912 | { | |
85c6e6e2 | 1913 | dbg_wl("close the WL sub-system"); |
74cdaf24 | 1914 | ubi_fastmap_close(ubi); |
849271a4 | 1915 | shutdown_work(ubi); |
7b6c32da | 1916 | protection_queue_destroy(ubi); |
ee59ba8b RW |
1917 | tree_destroy(ubi, &ubi->used); |
1918 | tree_destroy(ubi, &ubi->erroneous); | |
1919 | tree_destroy(ubi, &ubi->free); | |
1920 | tree_destroy(ubi, &ubi->scrub); | |
801c135c | 1921 | kfree(ubi->lookuptbl); |
801c135c AB |
1922 | } |
1923 | ||
801c135c | 1924 | /** |
7bf523ae | 1925 | * self_check_ec - make sure that the erase counter of a PEB is correct. |
801c135c AB |
1926 | * @ubi: UBI device description object |
1927 | * @pnum: the physical eraseblock number to check | |
1928 | * @ec: the erase counter to check | |
1929 | * | |
1930 | * This function returns zero if the erase counter of physical eraseblock @pnum | |
feddbb34 AB |
1931 | * is equivalent to @ec, and a negative error code if not or if an error |
1932 | * occurred. | |
801c135c | 1933 | */ |
7bf523ae | 1934 | static int self_check_ec(struct ubi_device *ubi, int pnum, int ec) |
801c135c AB |
1935 | { |
1936 | int err; | |
1937 | long long read_ec; | |
1938 | struct ubi_ec_hdr *ec_hdr; | |
1939 | ||
64575574 | 1940 | if (!ubi_dbg_chk_gen(ubi)) |
92d124f5 AB |
1941 | return 0; |
1942 | ||
33818bbb | 1943 | ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_NOFS); |
801c135c AB |
1944 | if (!ec_hdr) |
1945 | return -ENOMEM; | |
1946 | ||
1947 | err = ubi_io_read_ec_hdr(ubi, pnum, ec_hdr, 0); | |
1948 | if (err && err != UBI_IO_BITFLIPS) { | |
1949 | /* The header does not have to exist */ | |
1950 | err = 0; | |
1951 | goto out_free; | |
1952 | } | |
1953 | ||
3261ebd7 | 1954 | read_ec = be64_to_cpu(ec_hdr->ec); |
8199b901 | 1955 | if (ec != read_ec && read_ec - ec > 1) { |
32608703 TB |
1956 | ubi_err(ubi, "self-check failed for PEB %d", pnum); |
1957 | ubi_err(ubi, "read EC is %lld, should be %d", read_ec, ec); | |
25886a36 | 1958 | dump_stack(); |
801c135c AB |
1959 | err = 1; |
1960 | } else | |
1961 | err = 0; | |
1962 | ||
1963 | out_free: | |
1964 | kfree(ec_hdr); | |
1965 | return err; | |
1966 | } | |
1967 | ||
1968 | /** | |
7bf523ae | 1969 | * self_check_in_wl_tree - check that wear-leveling entry is in WL RB-tree. |
d99383b0 | 1970 | * @ubi: UBI device description object |
801c135c AB |
1971 | * @e: the wear-leveling entry to check |
1972 | * @root: the root of the tree | |
1973 | * | |
adbf05e3 AB |
1974 | * This function returns zero if @e is in the @root RB-tree and %-EINVAL if it |
1975 | * is not. | |
801c135c | 1976 | */ |
7bf523ae AB |
1977 | static int self_check_in_wl_tree(const struct ubi_device *ubi, |
1978 | struct ubi_wl_entry *e, struct rb_root *root) | |
801c135c | 1979 | { |
64575574 | 1980 | if (!ubi_dbg_chk_gen(ubi)) |
92d124f5 AB |
1981 | return 0; |
1982 | ||
801c135c AB |
1983 | if (in_wl_tree(e, root)) |
1984 | return 0; | |
1985 | ||
32608703 | 1986 | ubi_err(ubi, "self-check failed for PEB %d, EC %d, RB-tree %p ", |
801c135c | 1987 | e->pnum, e->ec, root); |
25886a36 | 1988 | dump_stack(); |
adbf05e3 | 1989 | return -EINVAL; |
801c135c AB |
1990 | } |
1991 | ||
7b6c32da | 1992 | /** |
7bf523ae | 1993 | * self_check_in_pq - check if wear-leveling entry is in the protection |
7b6c32da XX |
1994 | * queue. |
1995 | * @ubi: UBI device description object | |
1996 | * @e: the wear-leveling entry to check | |
1997 | * | |
adbf05e3 | 1998 | * This function returns zero if @e is in @ubi->pq and %-EINVAL if it is not. |
7b6c32da | 1999 | */ |
7bf523ae AB |
2000 | static int self_check_in_pq(const struct ubi_device *ubi, |
2001 | struct ubi_wl_entry *e) | |
7b6c32da | 2002 | { |
64575574 | 2003 | if (!ubi_dbg_chk_gen(ubi)) |
92d124f5 AB |
2004 | return 0; |
2005 | ||
b32b78f8 RW |
2006 | if (in_pq(ubi, e)) |
2007 | return 0; | |
7b6c32da | 2008 | |
32608703 | 2009 | ubi_err(ubi, "self-check failed for PEB %d, EC %d, Protect queue", |
7b6c32da | 2010 | e->pnum, e->ec); |
25886a36 | 2011 | dump_stack(); |
adbf05e3 | 2012 | return -EINVAL; |
7b6c32da | 2013 | } |
78d6d497 RW |
2014 | #ifndef CONFIG_MTD_UBI_FASTMAP |
2015 | static struct ubi_wl_entry *get_peb_for_wl(struct ubi_device *ubi) | |
2016 | { | |
2017 | struct ubi_wl_entry *e; | |
2018 | ||
2019 | e = find_wl_entry(ubi, &ubi->free, WL_FREE_MAX_DIFF); | |
2020 | self_check_in_wl_tree(ubi, e, &ubi->free); | |
2021 | ubi->free_count--; | |
2022 | ubi_assert(ubi->free_count >= 0); | |
2023 | rb_erase(&e->u.rb, &ubi->free); | |
2024 | ||
2025 | return e; | |
2026 | } | |
2027 | ||
2028 | /** | |
2029 | * produce_free_peb - produce a free physical eraseblock. | |
2030 | * @ubi: UBI device description object | |
2031 | * | |
2032 | * This function tries to make a free PEB by means of synchronous execution of | |
2033 | * pending works. This may be needed if, for example the background thread is | |
2034 | * disabled. Returns zero in case of success and a negative error code in case | |
2035 | * of failure. | |
2036 | */ | |
2037 | static int produce_free_peb(struct ubi_device *ubi) | |
2038 | { | |
2039 | int err; | |
2040 | ||
2041 | while (!ubi->free.rb_node && ubi->works_count) { | |
2042 | spin_unlock(&ubi->wl_lock); | |
2043 | ||
2044 | dbg_wl("do one work synchronously"); | |
2045 | err = do_work(ubi); | |
2046 | ||
2047 | spin_lock(&ubi->wl_lock); | |
2048 | if (err) | |
2049 | return err; | |
2050 | } | |
2051 | ||
2052 | return 0; | |
2053 | } | |
2054 | ||
2055 | /** | |
2056 | * ubi_wl_get_peb - get a physical eraseblock. | |
2057 | * @ubi: UBI device description object | |
2058 | * | |
2059 | * This function returns a physical eraseblock in case of success and a | |
2060 | * negative error code in case of failure. | |
2061 | * Returns with ubi->fm_eba_sem held in read mode! | |
2062 | */ | |
2063 | int ubi_wl_get_peb(struct ubi_device *ubi) | |
2064 | { | |
2065 | int err; | |
2066 | struct ubi_wl_entry *e; | |
2067 | ||
2068 | retry: | |
2069 | down_read(&ubi->fm_eba_sem); | |
2070 | spin_lock(&ubi->wl_lock); | |
2071 | if (!ubi->free.rb_node) { | |
2072 | if (ubi->works_count == 0) { | |
2073 | ubi_err(ubi, "no free eraseblocks"); | |
2074 | ubi_assert(list_empty(&ubi->works)); | |
2075 | spin_unlock(&ubi->wl_lock); | |
2076 | return -ENOSPC; | |
2077 | } | |
2078 | ||
2079 | err = produce_free_peb(ubi); | |
2080 | if (err < 0) { | |
2081 | spin_unlock(&ubi->wl_lock); | |
2082 | return err; | |
2083 | } | |
2084 | spin_unlock(&ubi->wl_lock); | |
2085 | up_read(&ubi->fm_eba_sem); | |
2086 | goto retry; | |
2087 | ||
2088 | } | |
2089 | e = wl_get_wle(ubi); | |
2090 | prot_queue_add(ubi, e); | |
2091 | spin_unlock(&ubi->wl_lock); | |
2092 | ||
2093 | err = ubi_self_check_all_ff(ubi, e->pnum, ubi->vid_hdr_aloffset, | |
2094 | ubi->peb_size - ubi->vid_hdr_aloffset); | |
2095 | if (err) { | |
2096 | ubi_err(ubi, "new PEB %d does not contain all 0xFF bytes", e->pnum); | |
2097 | return err; | |
2098 | } | |
2099 | ||
2100 | return e->pnum; | |
2101 | } | |
2102 | #else | |
2103 | #include "fastmap-wl.c" | |
2104 | #endif |