]> git.sur5r.net Git - u-boot/blob - drivers/mtd/ubi/fastmap.c
Merge branch 'zynq' of git://www.denx.de/git/u-boot-microblaze
[u-boot] / drivers / mtd / ubi / fastmap.c
1 /*
2  * Copyright (c) 2012 Linutronix GmbH
3  * Author: Richard Weinberger <richard@nod.at>
4  *
5  * SPDX-License-Identifier:     GPL-2.0+
6  *
7  */
8
9 #define __UBOOT__
10 #ifndef __UBOOT__
11 #include <linux/crc32.h>
12 #else
13 #include <div64.h>
14 #include <malloc.h>
15 #include <ubi_uboot.h>
16 #endif
17
18 #include <linux/compat.h>
19 #include <linux/math64.h>
20 #include "ubi.h"
21
22 /**
23  * ubi_calc_fm_size - calculates the fastmap size in bytes for an UBI device.
24  * @ubi: UBI device description object
25  */
26 size_t ubi_calc_fm_size(struct ubi_device *ubi)
27 {
28         size_t size;
29
30         size = sizeof(struct ubi_fm_hdr) + \
31                 sizeof(struct ubi_fm_scan_pool) + \
32                 sizeof(struct ubi_fm_scan_pool) + \
33                 (ubi->peb_count * sizeof(struct ubi_fm_ec)) + \
34                 (sizeof(struct ubi_fm_eba) + \
35                 (ubi->peb_count * sizeof(__be32))) + \
36                 sizeof(struct ubi_fm_volhdr) * UBI_MAX_VOLUMES;
37         return roundup(size, ubi->leb_size);
38 }
39
40
41 /**
42  * new_fm_vhdr - allocate a new volume header for fastmap usage.
43  * @ubi: UBI device description object
44  * @vol_id: the VID of the new header
45  *
46  * Returns a new struct ubi_vid_hdr on success.
47  * NULL indicates out of memory.
48  */
49 static struct ubi_vid_hdr *new_fm_vhdr(struct ubi_device *ubi, int vol_id)
50 {
51         struct ubi_vid_hdr *new;
52
53         new = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
54         if (!new)
55                 goto out;
56
57         new->vol_type = UBI_VID_DYNAMIC;
58         new->vol_id = cpu_to_be32(vol_id);
59
60         /* UBI implementations without fastmap support have to delete the
61          * fastmap.
62          */
63         new->compat = UBI_COMPAT_DELETE;
64
65 out:
66         return new;
67 }
68
69 /**
70  * add_aeb - create and add a attach erase block to a given list.
71  * @ai: UBI attach info object
72  * @list: the target list
73  * @pnum: PEB number of the new attach erase block
74  * @ec: erease counter of the new LEB
75  * @scrub: scrub this PEB after attaching
76  *
77  * Returns 0 on success, < 0 indicates an internal error.
78  */
79 static int add_aeb(struct ubi_attach_info *ai, struct list_head *list,
80                    int pnum, int ec, int scrub)
81 {
82         struct ubi_ainf_peb *aeb;
83
84         aeb = kmem_cache_alloc(ai->aeb_slab_cache, GFP_KERNEL);
85         if (!aeb)
86                 return -ENOMEM;
87
88         aeb->pnum = pnum;
89         aeb->ec = ec;
90         aeb->lnum = -1;
91         aeb->scrub = scrub;
92         aeb->copy_flag = aeb->sqnum = 0;
93
94         ai->ec_sum += aeb->ec;
95         ai->ec_count++;
96
97         if (ai->max_ec < aeb->ec)
98                 ai->max_ec = aeb->ec;
99
100         if (ai->min_ec > aeb->ec)
101                 ai->min_ec = aeb->ec;
102
103         list_add_tail(&aeb->u.list, list);
104
105         return 0;
106 }
107
108 /**
109  * add_vol - create and add a new volume to ubi_attach_info.
110  * @ai: ubi_attach_info object
111  * @vol_id: VID of the new volume
112  * @used_ebs: number of used EBS
113  * @data_pad: data padding value of the new volume
114  * @vol_type: volume type
115  * @last_eb_bytes: number of bytes in the last LEB
116  *
117  * Returns the new struct ubi_ainf_volume on success.
118  * NULL indicates an error.
119  */
120 static struct ubi_ainf_volume *add_vol(struct ubi_attach_info *ai, int vol_id,
121                                        int used_ebs, int data_pad, u8 vol_type,
122                                        int last_eb_bytes)
123 {
124         struct ubi_ainf_volume *av;
125         struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
126
127         while (*p) {
128                 parent = *p;
129                 av = rb_entry(parent, struct ubi_ainf_volume, rb);
130
131                 if (vol_id > av->vol_id)
132                         p = &(*p)->rb_left;
133                 else if (vol_id > av->vol_id)
134                         p = &(*p)->rb_right;
135         }
136
137         av = kmalloc(sizeof(struct ubi_ainf_volume), GFP_KERNEL);
138         if (!av)
139                 goto out;
140
141         av->highest_lnum = av->leb_count = 0;
142         av->vol_id = vol_id;
143         av->used_ebs = used_ebs;
144         av->data_pad = data_pad;
145         av->last_data_size = last_eb_bytes;
146         av->compat = 0;
147         av->vol_type = vol_type;
148         av->root = RB_ROOT;
149
150         dbg_bld("found volume (ID %i)", vol_id);
151
152         rb_link_node(&av->rb, parent, p);
153         rb_insert_color(&av->rb, &ai->volumes);
154
155 out:
156         return av;
157 }
158
159 /**
160  * assign_aeb_to_av - assigns a SEB to a given ainf_volume and removes it
161  * from it's original list.
162  * @ai: ubi_attach_info object
163  * @aeb: the to be assigned SEB
164  * @av: target scan volume
165  */
166 static void assign_aeb_to_av(struct ubi_attach_info *ai,
167                              struct ubi_ainf_peb *aeb,
168                              struct ubi_ainf_volume *av)
169 {
170         struct ubi_ainf_peb *tmp_aeb;
171         struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
172
173         p = &av->root.rb_node;
174         while (*p) {
175                 parent = *p;
176
177                 tmp_aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb);
178                 if (aeb->lnum != tmp_aeb->lnum) {
179                         if (aeb->lnum < tmp_aeb->lnum)
180                                 p = &(*p)->rb_left;
181                         else
182                                 p = &(*p)->rb_right;
183
184                         continue;
185                 } else
186                         break;
187         }
188
189         list_del(&aeb->u.list);
190         av->leb_count++;
191
192         rb_link_node(&aeb->u.rb, parent, p);
193         rb_insert_color(&aeb->u.rb, &av->root);
194 }
195
196 /**
197  * update_vol - inserts or updates a LEB which was found a pool.
198  * @ubi: the UBI device object
199  * @ai: attach info object
200  * @av: the volume this LEB belongs to
201  * @new_vh: the volume header derived from new_aeb
202  * @new_aeb: the AEB to be examined
203  *
204  * Returns 0 on success, < 0 indicates an internal error.
205  */
206 static int update_vol(struct ubi_device *ubi, struct ubi_attach_info *ai,
207                       struct ubi_ainf_volume *av, struct ubi_vid_hdr *new_vh,
208                       struct ubi_ainf_peb *new_aeb)
209 {
210         struct rb_node **p = &av->root.rb_node, *parent = NULL;
211         struct ubi_ainf_peb *aeb, *victim;
212         int cmp_res;
213
214         while (*p) {
215                 parent = *p;
216                 aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb);
217
218                 if (be32_to_cpu(new_vh->lnum) != aeb->lnum) {
219                         if (be32_to_cpu(new_vh->lnum) < aeb->lnum)
220                                 p = &(*p)->rb_left;
221                         else
222                                 p = &(*p)->rb_right;
223
224                         continue;
225                 }
226
227                 /* This case can happen if the fastmap gets written
228                  * because of a volume change (creation, deletion, ..).
229                  * Then a PEB can be within the persistent EBA and the pool.
230                  */
231                 if (aeb->pnum == new_aeb->pnum) {
232                         ubi_assert(aeb->lnum == new_aeb->lnum);
233                         kmem_cache_free(ai->aeb_slab_cache, new_aeb);
234
235                         return 0;
236                 }
237
238                 cmp_res = ubi_compare_lebs(ubi, aeb, new_aeb->pnum, new_vh);
239                 if (cmp_res < 0)
240                         return cmp_res;
241
242                 /* new_aeb is newer */
243                 if (cmp_res & 1) {
244                         victim = kmem_cache_alloc(ai->aeb_slab_cache,
245                                 GFP_KERNEL);
246                         if (!victim)
247                                 return -ENOMEM;
248
249                         victim->ec = aeb->ec;
250                         victim->pnum = aeb->pnum;
251                         list_add_tail(&victim->u.list, &ai->erase);
252
253                         if (av->highest_lnum == be32_to_cpu(new_vh->lnum))
254                                 av->last_data_size = \
255                                         be32_to_cpu(new_vh->data_size);
256
257                         dbg_bld("vol %i: AEB %i's PEB %i is the newer",
258                                 av->vol_id, aeb->lnum, new_aeb->pnum);
259
260                         aeb->ec = new_aeb->ec;
261                         aeb->pnum = new_aeb->pnum;
262                         aeb->copy_flag = new_vh->copy_flag;
263                         aeb->scrub = new_aeb->scrub;
264                         kmem_cache_free(ai->aeb_slab_cache, new_aeb);
265
266                 /* new_aeb is older */
267                 } else {
268                         dbg_bld("vol %i: AEB %i's PEB %i is old, dropping it",
269                                 av->vol_id, aeb->lnum, new_aeb->pnum);
270                         list_add_tail(&new_aeb->u.list, &ai->erase);
271                 }
272
273                 return 0;
274         }
275         /* This LEB is new, let's add it to the volume */
276
277         if (av->highest_lnum <= be32_to_cpu(new_vh->lnum)) {
278                 av->highest_lnum = be32_to_cpu(new_vh->lnum);
279                 av->last_data_size = be32_to_cpu(new_vh->data_size);
280         }
281
282         if (av->vol_type == UBI_STATIC_VOLUME)
283                 av->used_ebs = be32_to_cpu(new_vh->used_ebs);
284
285         av->leb_count++;
286
287         rb_link_node(&new_aeb->u.rb, parent, p);
288         rb_insert_color(&new_aeb->u.rb, &av->root);
289
290         return 0;
291 }
292
293 /**
294  * process_pool_aeb - we found a non-empty PEB in a pool.
295  * @ubi: UBI device object
296  * @ai: attach info object
297  * @new_vh: the volume header derived from new_aeb
298  * @new_aeb: the AEB to be examined
299  *
300  * Returns 0 on success, < 0 indicates an internal error.
301  */
302 static int process_pool_aeb(struct ubi_device *ubi, struct ubi_attach_info *ai,
303                             struct ubi_vid_hdr *new_vh,
304                             struct ubi_ainf_peb *new_aeb)
305 {
306         struct ubi_ainf_volume *av, *tmp_av = NULL;
307         struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
308         int found = 0;
309
310         if (be32_to_cpu(new_vh->vol_id) == UBI_FM_SB_VOLUME_ID ||
311                 be32_to_cpu(new_vh->vol_id) == UBI_FM_DATA_VOLUME_ID) {
312                 kmem_cache_free(ai->aeb_slab_cache, new_aeb);
313
314                 return 0;
315         }
316
317         /* Find the volume this SEB belongs to */
318         while (*p) {
319                 parent = *p;
320                 tmp_av = rb_entry(parent, struct ubi_ainf_volume, rb);
321
322                 if (be32_to_cpu(new_vh->vol_id) > tmp_av->vol_id)
323                         p = &(*p)->rb_left;
324                 else if (be32_to_cpu(new_vh->vol_id) < tmp_av->vol_id)
325                         p = &(*p)->rb_right;
326                 else {
327                         found = 1;
328                         break;
329                 }
330         }
331
332         if (found)
333                 av = tmp_av;
334         else {
335                 ubi_err("orphaned volume in fastmap pool!");
336                 return UBI_BAD_FASTMAP;
337         }
338
339         ubi_assert(be32_to_cpu(new_vh->vol_id) == av->vol_id);
340
341         return update_vol(ubi, ai, av, new_vh, new_aeb);
342 }
343
344 /**
345  * unmap_peb - unmap a PEB.
346  * If fastmap detects a free PEB in the pool it has to check whether
347  * this PEB has been unmapped after writing the fastmap.
348  *
349  * @ai: UBI attach info object
350  * @pnum: The PEB to be unmapped
351  */
352 static void unmap_peb(struct ubi_attach_info *ai, int pnum)
353 {
354         struct ubi_ainf_volume *av;
355         struct rb_node *node, *node2;
356         struct ubi_ainf_peb *aeb;
357
358         for (node = rb_first(&ai->volumes); node; node = rb_next(node)) {
359                 av = rb_entry(node, struct ubi_ainf_volume, rb);
360
361                 for (node2 = rb_first(&av->root); node2;
362                      node2 = rb_next(node2)) {
363                         aeb = rb_entry(node2, struct ubi_ainf_peb, u.rb);
364                         if (aeb->pnum == pnum) {
365                                 rb_erase(&aeb->u.rb, &av->root);
366                                 kmem_cache_free(ai->aeb_slab_cache, aeb);
367                                 return;
368                         }
369                 }
370         }
371 }
372
373 /**
374  * scan_pool - scans a pool for changed (no longer empty PEBs).
375  * @ubi: UBI device object
376  * @ai: attach info object
377  * @pebs: an array of all PEB numbers in the to be scanned pool
378  * @pool_size: size of the pool (number of entries in @pebs)
379  * @max_sqnum: pointer to the maximal sequence number
380  * @eba_orphans: list of PEBs which need to be scanned
381  * @free: list of PEBs which are most likely free (and go into @ai->free)
382  *
383  * Returns 0 on success, if the pool is unusable UBI_BAD_FASTMAP is returned.
384  * < 0 indicates an internal error.
385  */
386 #ifndef __UBOOT__
387 static int scan_pool(struct ubi_device *ubi, struct ubi_attach_info *ai,
388                      int *pebs, int pool_size, unsigned long long *max_sqnum,
389                      struct list_head *eba_orphans, struct list_head *freef)
390 #else
391 static int scan_pool(struct ubi_device *ubi, struct ubi_attach_info *ai,
392                      __be32 *pebs, int pool_size, unsigned long long *max_sqnum,
393                      struct list_head *eba_orphans, struct list_head *freef)
394 #endif
395 {
396         struct ubi_vid_hdr *vh;
397         struct ubi_ec_hdr *ech;
398         struct ubi_ainf_peb *new_aeb, *tmp_aeb;
399         int i, pnum, err, found_orphan, ret = 0;
400
401         ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
402         if (!ech)
403                 return -ENOMEM;
404
405         vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
406         if (!vh) {
407                 kfree(ech);
408                 return -ENOMEM;
409         }
410
411         dbg_bld("scanning fastmap pool: size = %i", pool_size);
412
413         /*
414          * Now scan all PEBs in the pool to find changes which have been made
415          * after the creation of the fastmap
416          */
417         for (i = 0; i < pool_size; i++) {
418                 int scrub = 0;
419                 int image_seq;
420
421                 pnum = be32_to_cpu(pebs[i]);
422
423                 if (ubi_io_is_bad(ubi, pnum)) {
424                         ubi_err("bad PEB in fastmap pool!");
425                         ret = UBI_BAD_FASTMAP;
426                         goto out;
427                 }
428
429                 err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
430                 if (err && err != UBI_IO_BITFLIPS) {
431                         ubi_err("unable to read EC header! PEB:%i err:%i",
432                                 pnum, err);
433                         ret = err > 0 ? UBI_BAD_FASTMAP : err;
434                         goto out;
435                 } else if (ret == UBI_IO_BITFLIPS)
436                         scrub = 1;
437
438                 /*
439                  * Older UBI implementations have image_seq set to zero, so
440                  * we shouldn't fail if image_seq == 0.
441                  */
442                 image_seq = be32_to_cpu(ech->image_seq);
443
444                 if (image_seq && (image_seq != ubi->image_seq)) {
445                         ubi_err("bad image seq: 0x%x, expected: 0x%x",
446                                 be32_to_cpu(ech->image_seq), ubi->image_seq);
447                         ret = UBI_BAD_FASTMAP;
448                         goto out;
449                 }
450
451                 err = ubi_io_read_vid_hdr(ubi, pnum, vh, 0);
452                 if (err == UBI_IO_FF || err == UBI_IO_FF_BITFLIPS) {
453                         unsigned long long ec = be64_to_cpu(ech->ec);
454                         unmap_peb(ai, pnum);
455                         dbg_bld("Adding PEB to free: %i", pnum);
456                         if (err == UBI_IO_FF_BITFLIPS)
457                                 add_aeb(ai, freef, pnum, ec, 1);
458                         else
459                                 add_aeb(ai, freef, pnum, ec, 0);
460                         continue;
461                 } else if (err == 0 || err == UBI_IO_BITFLIPS) {
462                         dbg_bld("Found non empty PEB:%i in pool", pnum);
463
464                         if (err == UBI_IO_BITFLIPS)
465                                 scrub = 1;
466
467                         found_orphan = 0;
468                         list_for_each_entry(tmp_aeb, eba_orphans, u.list) {
469                                 if (tmp_aeb->pnum == pnum) {
470                                         found_orphan = 1;
471                                         break;
472                                 }
473                         }
474                         if (found_orphan) {
475                                 list_del(&tmp_aeb->u.list);
476                                 kmem_cache_free(ai->aeb_slab_cache, tmp_aeb);
477                         }
478
479                         new_aeb = kmem_cache_alloc(ai->aeb_slab_cache,
480                                                    GFP_KERNEL);
481                         if (!new_aeb) {
482                                 ret = -ENOMEM;
483                                 goto out;
484                         }
485
486                         new_aeb->ec = be64_to_cpu(ech->ec);
487                         new_aeb->pnum = pnum;
488                         new_aeb->lnum = be32_to_cpu(vh->lnum);
489                         new_aeb->sqnum = be64_to_cpu(vh->sqnum);
490                         new_aeb->copy_flag = vh->copy_flag;
491                         new_aeb->scrub = scrub;
492
493                         if (*max_sqnum < new_aeb->sqnum)
494                                 *max_sqnum = new_aeb->sqnum;
495
496                         err = process_pool_aeb(ubi, ai, vh, new_aeb);
497                         if (err) {
498                                 ret = err > 0 ? UBI_BAD_FASTMAP : err;
499                                 goto out;
500                         }
501                 } else {
502                         /* We are paranoid and fall back to scanning mode */
503                         ubi_err("fastmap pool PEBs contains damaged PEBs!");
504                         ret = err > 0 ? UBI_BAD_FASTMAP : err;
505                         goto out;
506                 }
507
508         }
509
510 out:
511         ubi_free_vid_hdr(ubi, vh);
512         kfree(ech);
513         return ret;
514 }
515
516 /**
517  * count_fastmap_pebs - Counts the PEBs found by fastmap.
518  * @ai: The UBI attach info object
519  */
520 static int count_fastmap_pebs(struct ubi_attach_info *ai)
521 {
522         struct ubi_ainf_peb *aeb;
523         struct ubi_ainf_volume *av;
524         struct rb_node *rb1, *rb2;
525         int n = 0;
526
527         list_for_each_entry(aeb, &ai->erase, u.list)
528                 n++;
529
530         list_for_each_entry(aeb, &ai->free, u.list)
531                 n++;
532
533          ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb)
534                 ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb)
535                         n++;
536
537         return n;
538 }
539
540 /**
541  * ubi_attach_fastmap - creates ubi_attach_info from a fastmap.
542  * @ubi: UBI device object
543  * @ai: UBI attach info object
544  * @fm: the fastmap to be attached
545  *
546  * Returns 0 on success, UBI_BAD_FASTMAP if the found fastmap was unusable.
547  * < 0 indicates an internal error.
548  */
549 static int ubi_attach_fastmap(struct ubi_device *ubi,
550                               struct ubi_attach_info *ai,
551                               struct ubi_fastmap_layout *fm)
552 {
553         struct list_head used, eba_orphans, freef;
554         struct ubi_ainf_volume *av;
555         struct ubi_ainf_peb *aeb, *tmp_aeb, *_tmp_aeb;
556         struct ubi_ec_hdr *ech;
557         struct ubi_fm_sb *fmsb;
558         struct ubi_fm_hdr *fmhdr;
559         struct ubi_fm_scan_pool *fmpl1, *fmpl2;
560         struct ubi_fm_ec *fmec;
561         struct ubi_fm_volhdr *fmvhdr;
562         struct ubi_fm_eba *fm_eba;
563         int ret, i, j, pool_size, wl_pool_size;
564         size_t fm_pos = 0, fm_size = ubi->fm_size;
565         unsigned long long max_sqnum = 0;
566         void *fm_raw = ubi->fm_buf;
567
568         INIT_LIST_HEAD(&used);
569         INIT_LIST_HEAD(&freef);
570         INIT_LIST_HEAD(&eba_orphans);
571         INIT_LIST_HEAD(&ai->corr);
572         INIT_LIST_HEAD(&ai->free);
573         INIT_LIST_HEAD(&ai->erase);
574         INIT_LIST_HEAD(&ai->alien);
575         ai->volumes = RB_ROOT;
576         ai->min_ec = UBI_MAX_ERASECOUNTER;
577
578         ai->aeb_slab_cache = kmem_cache_create("ubi_ainf_peb_slab",
579                                                sizeof(struct ubi_ainf_peb),
580                                                0, 0, NULL);
581         if (!ai->aeb_slab_cache) {
582                 ret = -ENOMEM;
583                 goto fail;
584         }
585
586         fmsb = (struct ubi_fm_sb *)(fm_raw);
587         ai->max_sqnum = fmsb->sqnum;
588         fm_pos += sizeof(struct ubi_fm_sb);
589         if (fm_pos >= fm_size)
590                 goto fail_bad;
591
592         fmhdr = (struct ubi_fm_hdr *)(fm_raw + fm_pos);
593         fm_pos += sizeof(*fmhdr);
594         if (fm_pos >= fm_size)
595                 goto fail_bad;
596
597         if (be32_to_cpu(fmhdr->magic) != UBI_FM_HDR_MAGIC) {
598                 ubi_err("bad fastmap header magic: 0x%x, expected: 0x%x",
599                         be32_to_cpu(fmhdr->magic), UBI_FM_HDR_MAGIC);
600                 goto fail_bad;
601         }
602
603         fmpl1 = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
604         fm_pos += sizeof(*fmpl1);
605         if (fm_pos >= fm_size)
606                 goto fail_bad;
607         if (be32_to_cpu(fmpl1->magic) != UBI_FM_POOL_MAGIC) {
608                 ubi_err("bad fastmap pool magic: 0x%x, expected: 0x%x",
609                         be32_to_cpu(fmpl1->magic), UBI_FM_POOL_MAGIC);
610                 goto fail_bad;
611         }
612
613         fmpl2 = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
614         fm_pos += sizeof(*fmpl2);
615         if (fm_pos >= fm_size)
616                 goto fail_bad;
617         if (be32_to_cpu(fmpl2->magic) != UBI_FM_POOL_MAGIC) {
618                 ubi_err("bad fastmap pool magic: 0x%x, expected: 0x%x",
619                         be32_to_cpu(fmpl2->magic), UBI_FM_POOL_MAGIC);
620                 goto fail_bad;
621         }
622
623         pool_size = be16_to_cpu(fmpl1->size);
624         wl_pool_size = be16_to_cpu(fmpl2->size);
625         fm->max_pool_size = be16_to_cpu(fmpl1->max_size);
626         fm->max_wl_pool_size = be16_to_cpu(fmpl2->max_size);
627
628         if (pool_size > UBI_FM_MAX_POOL_SIZE || pool_size < 0) {
629                 ubi_err("bad pool size: %i", pool_size);
630                 goto fail_bad;
631         }
632
633         if (wl_pool_size > UBI_FM_MAX_POOL_SIZE || wl_pool_size < 0) {
634                 ubi_err("bad WL pool size: %i", wl_pool_size);
635                 goto fail_bad;
636         }
637
638
639         if (fm->max_pool_size > UBI_FM_MAX_POOL_SIZE ||
640             fm->max_pool_size < 0) {
641                 ubi_err("bad maximal pool size: %i", fm->max_pool_size);
642                 goto fail_bad;
643         }
644
645         if (fm->max_wl_pool_size > UBI_FM_MAX_POOL_SIZE ||
646             fm->max_wl_pool_size < 0) {
647                 ubi_err("bad maximal WL pool size: %i", fm->max_wl_pool_size);
648                 goto fail_bad;
649         }
650
651         /* read EC values from free list */
652         for (i = 0; i < be32_to_cpu(fmhdr->free_peb_count); i++) {
653                 fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
654                 fm_pos += sizeof(*fmec);
655                 if (fm_pos >= fm_size)
656                         goto fail_bad;
657
658                 add_aeb(ai, &ai->free, be32_to_cpu(fmec->pnum),
659                         be32_to_cpu(fmec->ec), 0);
660         }
661
662         /* read EC values from used list */
663         for (i = 0; i < be32_to_cpu(fmhdr->used_peb_count); i++) {
664                 fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
665                 fm_pos += sizeof(*fmec);
666                 if (fm_pos >= fm_size)
667                         goto fail_bad;
668
669                 add_aeb(ai, &used, be32_to_cpu(fmec->pnum),
670                         be32_to_cpu(fmec->ec), 0);
671         }
672
673         /* read EC values from scrub list */
674         for (i = 0; i < be32_to_cpu(fmhdr->scrub_peb_count); i++) {
675                 fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
676                 fm_pos += sizeof(*fmec);
677                 if (fm_pos >= fm_size)
678                         goto fail_bad;
679
680                 add_aeb(ai, &used, be32_to_cpu(fmec->pnum),
681                         be32_to_cpu(fmec->ec), 1);
682         }
683
684         /* read EC values from erase list */
685         for (i = 0; i < be32_to_cpu(fmhdr->erase_peb_count); i++) {
686                 fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
687                 fm_pos += sizeof(*fmec);
688                 if (fm_pos >= fm_size)
689                         goto fail_bad;
690
691                 add_aeb(ai, &ai->erase, be32_to_cpu(fmec->pnum),
692                         be32_to_cpu(fmec->ec), 1);
693         }
694
695         ai->mean_ec = div_u64(ai->ec_sum, ai->ec_count);
696         ai->bad_peb_count = be32_to_cpu(fmhdr->bad_peb_count);
697
698         /* Iterate over all volumes and read their EBA table */
699         for (i = 0; i < be32_to_cpu(fmhdr->vol_count); i++) {
700                 fmvhdr = (struct ubi_fm_volhdr *)(fm_raw + fm_pos);
701                 fm_pos += sizeof(*fmvhdr);
702                 if (fm_pos >= fm_size)
703                         goto fail_bad;
704
705                 if (be32_to_cpu(fmvhdr->magic) != UBI_FM_VHDR_MAGIC) {
706                         ubi_err("bad fastmap vol header magic: 0x%x, " \
707                                 "expected: 0x%x",
708                                 be32_to_cpu(fmvhdr->magic), UBI_FM_VHDR_MAGIC);
709                         goto fail_bad;
710                 }
711
712                 av = add_vol(ai, be32_to_cpu(fmvhdr->vol_id),
713                              be32_to_cpu(fmvhdr->used_ebs),
714                              be32_to_cpu(fmvhdr->data_pad),
715                              fmvhdr->vol_type,
716                              be32_to_cpu(fmvhdr->last_eb_bytes));
717
718                 if (!av)
719                         goto fail_bad;
720
721                 ai->vols_found++;
722                 if (ai->highest_vol_id < be32_to_cpu(fmvhdr->vol_id))
723                         ai->highest_vol_id = be32_to_cpu(fmvhdr->vol_id);
724
725                 fm_eba = (struct ubi_fm_eba *)(fm_raw + fm_pos);
726                 fm_pos += sizeof(*fm_eba);
727                 fm_pos += (sizeof(__be32) * be32_to_cpu(fm_eba->reserved_pebs));
728                 if (fm_pos >= fm_size)
729                         goto fail_bad;
730
731                 if (be32_to_cpu(fm_eba->magic) != UBI_FM_EBA_MAGIC) {
732                         ubi_err("bad fastmap EBA header magic: 0x%x, " \
733                                 "expected: 0x%x",
734                                 be32_to_cpu(fm_eba->magic), UBI_FM_EBA_MAGIC);
735                         goto fail_bad;
736                 }
737
738                 for (j = 0; j < be32_to_cpu(fm_eba->reserved_pebs); j++) {
739                         int pnum = be32_to_cpu(fm_eba->pnum[j]);
740
741                         if ((int)be32_to_cpu(fm_eba->pnum[j]) < 0)
742                                 continue;
743
744                         aeb = NULL;
745                         list_for_each_entry(tmp_aeb, &used, u.list) {
746                                 if (tmp_aeb->pnum == pnum) {
747                                         aeb = tmp_aeb;
748                                         break;
749                                 }
750                         }
751
752                         /* This can happen if a PEB is already in an EBA known
753                          * by this fastmap but the PEB itself is not in the used
754                          * list.
755                          * In this case the PEB can be within the fastmap pool
756                          * or while writing the fastmap it was in the protection
757                          * queue.
758                          */
759                         if (!aeb) {
760                                 aeb = kmem_cache_alloc(ai->aeb_slab_cache,
761                                                        GFP_KERNEL);
762                                 if (!aeb) {
763                                         ret = -ENOMEM;
764
765                                         goto fail;
766                                 }
767
768                                 aeb->lnum = j;
769                                 aeb->pnum = be32_to_cpu(fm_eba->pnum[j]);
770                                 aeb->ec = -1;
771                                 aeb->scrub = aeb->copy_flag = aeb->sqnum = 0;
772                                 list_add_tail(&aeb->u.list, &eba_orphans);
773                                 continue;
774                         }
775
776                         aeb->lnum = j;
777
778                         if (av->highest_lnum <= aeb->lnum)
779                                 av->highest_lnum = aeb->lnum;
780
781                         assign_aeb_to_av(ai, aeb, av);
782
783                         dbg_bld("inserting PEB:%i (LEB %i) to vol %i",
784                                 aeb->pnum, aeb->lnum, av->vol_id);
785                 }
786
787                 ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
788                 if (!ech) {
789                         ret = -ENOMEM;
790                         goto fail;
791                 }
792
793                 list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &eba_orphans,
794                                          u.list) {
795                         int err;
796
797                         if (ubi_io_is_bad(ubi, tmp_aeb->pnum)) {
798                                 ubi_err("bad PEB in fastmap EBA orphan list");
799                                 ret = UBI_BAD_FASTMAP;
800                                 kfree(ech);
801                                 goto fail;
802                         }
803
804                         err = ubi_io_read_ec_hdr(ubi, tmp_aeb->pnum, ech, 0);
805                         if (err && err != UBI_IO_BITFLIPS) {
806                                 ubi_err("unable to read EC header! PEB:%i " \
807                                         "err:%i", tmp_aeb->pnum, err);
808                                 ret = err > 0 ? UBI_BAD_FASTMAP : err;
809                                 kfree(ech);
810
811                                 goto fail;
812                         } else if (err == UBI_IO_BITFLIPS)
813                                 tmp_aeb->scrub = 1;
814
815                         tmp_aeb->ec = be64_to_cpu(ech->ec);
816                         assign_aeb_to_av(ai, tmp_aeb, av);
817                 }
818
819                 kfree(ech);
820         }
821
822         ret = scan_pool(ubi, ai, fmpl1->pebs, pool_size, &max_sqnum,
823                         &eba_orphans, &freef);
824         if (ret)
825                 goto fail;
826
827         ret = scan_pool(ubi, ai, fmpl2->pebs, wl_pool_size, &max_sqnum,
828                         &eba_orphans, &freef);
829         if (ret)
830                 goto fail;
831
832         if (max_sqnum > ai->max_sqnum)
833                 ai->max_sqnum = max_sqnum;
834
835         list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &freef, u.list)
836                 list_move_tail(&tmp_aeb->u.list, &ai->free);
837
838         ubi_assert(list_empty(&used));
839         ubi_assert(list_empty(&eba_orphans));
840         ubi_assert(list_empty(&freef));
841
842         /*
843          * If fastmap is leaking PEBs (must not happen), raise a
844          * fat warning and fall back to scanning mode.
845          * We do this here because in ubi_wl_init() it's too late
846          * and we cannot fall back to scanning.
847          */
848 #ifndef __UBOOT__
849         if (WARN_ON(count_fastmap_pebs(ai) != ubi->peb_count -
850                     ai->bad_peb_count - fm->used_blocks))
851                 goto fail_bad;
852 #else
853         if (count_fastmap_pebs(ai) != ubi->peb_count -
854                     ai->bad_peb_count - fm->used_blocks) {
855                 WARN_ON(1);
856                 goto fail_bad;
857         }
858 #endif
859
860         return 0;
861
862 fail_bad:
863         ret = UBI_BAD_FASTMAP;
864 fail:
865         list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &used, u.list) {
866                 list_del(&tmp_aeb->u.list);
867                 kmem_cache_free(ai->aeb_slab_cache, tmp_aeb);
868         }
869         list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &eba_orphans, u.list) {
870                 list_del(&tmp_aeb->u.list);
871                 kmem_cache_free(ai->aeb_slab_cache, tmp_aeb);
872         }
873         list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &freef, u.list) {
874                 list_del(&tmp_aeb->u.list);
875                 kmem_cache_free(ai->aeb_slab_cache, tmp_aeb);
876         }
877
878         return ret;
879 }
880
881 /**
882  * ubi_scan_fastmap - scan the fastmap.
883  * @ubi: UBI device object
884  * @ai: UBI attach info to be filled
885  * @fm_anchor: The fastmap starts at this PEB
886  *
887  * Returns 0 on success, UBI_NO_FASTMAP if no fastmap was found,
888  * UBI_BAD_FASTMAP if one was found but is not usable.
889  * < 0 indicates an internal error.
890  */
891 int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
892                      int fm_anchor)
893 {
894         struct ubi_fm_sb *fmsb, *fmsb2;
895         struct ubi_vid_hdr *vh;
896         struct ubi_ec_hdr *ech;
897         struct ubi_fastmap_layout *fm;
898         int i, used_blocks, pnum, ret = 0;
899         size_t fm_size;
900         __be32 crc, tmp_crc;
901         unsigned long long sqnum = 0;
902
903         mutex_lock(&ubi->fm_mutex);
904         memset(ubi->fm_buf, 0, ubi->fm_size);
905
906         fmsb = kmalloc(sizeof(*fmsb), GFP_KERNEL);
907         if (!fmsb) {
908                 ret = -ENOMEM;
909                 goto out;
910         }
911
912         fm = kzalloc(sizeof(*fm), GFP_KERNEL);
913         if (!fm) {
914                 ret = -ENOMEM;
915                 kfree(fmsb);
916                 goto out;
917         }
918
919         ret = ubi_io_read(ubi, fmsb, fm_anchor, ubi->leb_start, sizeof(*fmsb));
920         if (ret && ret != UBI_IO_BITFLIPS)
921                 goto free_fm_sb;
922         else if (ret == UBI_IO_BITFLIPS)
923                 fm->to_be_tortured[0] = 1;
924
925         if (be32_to_cpu(fmsb->magic) != UBI_FM_SB_MAGIC) {
926                 ubi_err("bad super block magic: 0x%x, expected: 0x%x",
927                         be32_to_cpu(fmsb->magic), UBI_FM_SB_MAGIC);
928                 ret = UBI_BAD_FASTMAP;
929                 goto free_fm_sb;
930         }
931
932         if (fmsb->version != UBI_FM_FMT_VERSION) {
933                 ubi_err("bad fastmap version: %i, expected: %i",
934                         fmsb->version, UBI_FM_FMT_VERSION);
935                 ret = UBI_BAD_FASTMAP;
936                 goto free_fm_sb;
937         }
938
939         used_blocks = be32_to_cpu(fmsb->used_blocks);
940         if (used_blocks > UBI_FM_MAX_BLOCKS || used_blocks < 1) {
941                 ubi_err("number of fastmap blocks is invalid: %i", used_blocks);
942                 ret = UBI_BAD_FASTMAP;
943                 goto free_fm_sb;
944         }
945
946         fm_size = ubi->leb_size * used_blocks;
947         if (fm_size != ubi->fm_size) {
948                 ubi_err("bad fastmap size: %zi, expected: %zi", fm_size,
949                         ubi->fm_size);
950                 ret = UBI_BAD_FASTMAP;
951                 goto free_fm_sb;
952         }
953
954         ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
955         if (!ech) {
956                 ret = -ENOMEM;
957                 goto free_fm_sb;
958         }
959
960         vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
961         if (!vh) {
962                 ret = -ENOMEM;
963                 goto free_hdr;
964         }
965
966         for (i = 0; i < used_blocks; i++) {
967                 int image_seq;
968
969                 pnum = be32_to_cpu(fmsb->block_loc[i]);
970
971                 if (ubi_io_is_bad(ubi, pnum)) {
972                         ret = UBI_BAD_FASTMAP;
973                         goto free_hdr;
974                 }
975
976                 ret = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
977                 if (ret && ret != UBI_IO_BITFLIPS) {
978                         ubi_err("unable to read fastmap block# %i EC (PEB: %i)",
979                                 i, pnum);
980                         if (ret > 0)
981                                 ret = UBI_BAD_FASTMAP;
982                         goto free_hdr;
983                 } else if (ret == UBI_IO_BITFLIPS)
984                         fm->to_be_tortured[i] = 1;
985
986                 image_seq = be32_to_cpu(ech->image_seq);
987                 if (!ubi->image_seq)
988                         ubi->image_seq = image_seq;
989
990                 /*
991                  * Older UBI implementations have image_seq set to zero, so
992                  * we shouldn't fail if image_seq == 0.
993                  */
994                 if (image_seq && (image_seq != ubi->image_seq)) {
995                         ubi_err("wrong image seq:%d instead of %d",
996                                 be32_to_cpu(ech->image_seq), ubi->image_seq);
997                         ret = UBI_BAD_FASTMAP;
998                         goto free_hdr;
999                 }
1000
1001                 ret = ubi_io_read_vid_hdr(ubi, pnum, vh, 0);
1002                 if (ret && ret != UBI_IO_BITFLIPS) {
1003                         ubi_err("unable to read fastmap block# %i (PEB: %i)",
1004                                 i, pnum);
1005                         goto free_hdr;
1006                 }
1007
1008                 if (i == 0) {
1009                         if (be32_to_cpu(vh->vol_id) != UBI_FM_SB_VOLUME_ID) {
1010                                 ubi_err("bad fastmap anchor vol_id: 0x%x," \
1011                                         " expected: 0x%x",
1012                                         be32_to_cpu(vh->vol_id),
1013                                         UBI_FM_SB_VOLUME_ID);
1014                                 ret = UBI_BAD_FASTMAP;
1015                                 goto free_hdr;
1016                         }
1017                 } else {
1018                         if (be32_to_cpu(vh->vol_id) != UBI_FM_DATA_VOLUME_ID) {
1019                                 ubi_err("bad fastmap data vol_id: 0x%x," \
1020                                         " expected: 0x%x",
1021                                         be32_to_cpu(vh->vol_id),
1022                                         UBI_FM_DATA_VOLUME_ID);
1023                                 ret = UBI_BAD_FASTMAP;
1024                                 goto free_hdr;
1025                         }
1026                 }
1027
1028                 if (sqnum < be64_to_cpu(vh->sqnum))
1029                         sqnum = be64_to_cpu(vh->sqnum);
1030
1031                 ret = ubi_io_read(ubi, ubi->fm_buf + (ubi->leb_size * i), pnum,
1032                                   ubi->leb_start, ubi->leb_size);
1033                 if (ret && ret != UBI_IO_BITFLIPS) {
1034                         ubi_err("unable to read fastmap block# %i (PEB: %i, " \
1035                                 "err: %i)", i, pnum, ret);
1036                         goto free_hdr;
1037                 }
1038         }
1039
1040         kfree(fmsb);
1041         fmsb = NULL;
1042
1043         fmsb2 = (struct ubi_fm_sb *)(ubi->fm_buf);
1044         tmp_crc = be32_to_cpu(fmsb2->data_crc);
1045         fmsb2->data_crc = 0;
1046         crc = crc32(UBI_CRC32_INIT, ubi->fm_buf, fm_size);
1047         if (crc != tmp_crc) {
1048                 ubi_err("fastmap data CRC is invalid");
1049                 ubi_err("CRC should be: 0x%x, calc: 0x%x", tmp_crc, crc);
1050                 ret = UBI_BAD_FASTMAP;
1051                 goto free_hdr;
1052         }
1053
1054         fmsb2->sqnum = sqnum;
1055
1056         fm->used_blocks = used_blocks;
1057
1058         ret = ubi_attach_fastmap(ubi, ai, fm);
1059         if (ret) {
1060                 if (ret > 0)
1061                         ret = UBI_BAD_FASTMAP;
1062                 goto free_hdr;
1063         }
1064
1065         for (i = 0; i < used_blocks; i++) {
1066                 struct ubi_wl_entry *e;
1067
1068                 e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL);
1069                 if (!e) {
1070                         while (i--)
1071                                 kfree(fm->e[i]);
1072
1073                         ret = -ENOMEM;
1074                         goto free_hdr;
1075                 }
1076
1077                 e->pnum = be32_to_cpu(fmsb2->block_loc[i]);
1078                 e->ec = be32_to_cpu(fmsb2->block_ec[i]);
1079                 fm->e[i] = e;
1080         }
1081
1082         ubi->fm = fm;
1083         ubi->fm_pool.max_size = ubi->fm->max_pool_size;
1084         ubi->fm_wl_pool.max_size = ubi->fm->max_wl_pool_size;
1085         ubi_msg("attached by fastmap");
1086         ubi_msg("fastmap pool size: %d", ubi->fm_pool.max_size);
1087         ubi_msg("fastmap WL pool size: %d", ubi->fm_wl_pool.max_size);
1088         ubi->fm_disabled = 0;
1089
1090         ubi_free_vid_hdr(ubi, vh);
1091         kfree(ech);
1092 out:
1093         mutex_unlock(&ubi->fm_mutex);
1094         if (ret == UBI_BAD_FASTMAP)
1095                 ubi_err("Attach by fastmap failed, doing a full scan!");
1096         return ret;
1097
1098 free_hdr:
1099         ubi_free_vid_hdr(ubi, vh);
1100         kfree(ech);
1101 free_fm_sb:
1102         kfree(fmsb);
1103         kfree(fm);
1104         goto out;
1105 }
1106
1107 /**
1108  * ubi_write_fastmap - writes a fastmap.
1109  * @ubi: UBI device object
1110  * @new_fm: the to be written fastmap
1111  *
1112  * Returns 0 on success, < 0 indicates an internal error.
1113  */
1114 static int ubi_write_fastmap(struct ubi_device *ubi,
1115                              struct ubi_fastmap_layout *new_fm)
1116 {
1117         size_t fm_pos = 0;
1118         void *fm_raw;
1119         struct ubi_fm_sb *fmsb;
1120         struct ubi_fm_hdr *fmh;
1121         struct ubi_fm_scan_pool *fmpl1, *fmpl2;
1122         struct ubi_fm_ec *fec;
1123         struct ubi_fm_volhdr *fvh;
1124         struct ubi_fm_eba *feba;
1125         struct rb_node *node;
1126         struct ubi_wl_entry *wl_e;
1127         struct ubi_volume *vol;
1128         struct ubi_vid_hdr *avhdr, *dvhdr;
1129         struct ubi_work *ubi_wrk;
1130         int ret, i, j, free_peb_count, used_peb_count, vol_count;
1131         int scrub_peb_count, erase_peb_count;
1132
1133         fm_raw = ubi->fm_buf;
1134         memset(ubi->fm_buf, 0, ubi->fm_size);
1135
1136         avhdr = new_fm_vhdr(ubi, UBI_FM_SB_VOLUME_ID);
1137         if (!avhdr) {
1138                 ret = -ENOMEM;
1139                 goto out;
1140         }
1141
1142         dvhdr = new_fm_vhdr(ubi, UBI_FM_DATA_VOLUME_ID);
1143         if (!dvhdr) {
1144                 ret = -ENOMEM;
1145                 goto out_kfree;
1146         }
1147
1148         spin_lock(&ubi->volumes_lock);
1149         spin_lock(&ubi->wl_lock);
1150
1151         fmsb = (struct ubi_fm_sb *)fm_raw;
1152         fm_pos += sizeof(*fmsb);
1153         ubi_assert(fm_pos <= ubi->fm_size);
1154
1155         fmh = (struct ubi_fm_hdr *)(fm_raw + fm_pos);
1156         fm_pos += sizeof(*fmh);
1157         ubi_assert(fm_pos <= ubi->fm_size);
1158
1159         fmsb->magic = cpu_to_be32(UBI_FM_SB_MAGIC);
1160         fmsb->version = UBI_FM_FMT_VERSION;
1161         fmsb->used_blocks = cpu_to_be32(new_fm->used_blocks);
1162         /* the max sqnum will be filled in while *reading* the fastmap */
1163         fmsb->sqnum = 0;
1164
1165         fmh->magic = cpu_to_be32(UBI_FM_HDR_MAGIC);
1166         free_peb_count = 0;
1167         used_peb_count = 0;
1168         scrub_peb_count = 0;
1169         erase_peb_count = 0;
1170         vol_count = 0;
1171
1172         fmpl1 = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
1173         fm_pos += sizeof(*fmpl1);
1174         fmpl1->magic = cpu_to_be32(UBI_FM_POOL_MAGIC);
1175         fmpl1->size = cpu_to_be16(ubi->fm_pool.size);
1176         fmpl1->max_size = cpu_to_be16(ubi->fm_pool.max_size);
1177
1178         for (i = 0; i < ubi->fm_pool.size; i++)
1179                 fmpl1->pebs[i] = cpu_to_be32(ubi->fm_pool.pebs[i]);
1180
1181         fmpl2 = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
1182         fm_pos += sizeof(*fmpl2);
1183         fmpl2->magic = cpu_to_be32(UBI_FM_POOL_MAGIC);
1184         fmpl2->size = cpu_to_be16(ubi->fm_wl_pool.size);
1185         fmpl2->max_size = cpu_to_be16(ubi->fm_wl_pool.max_size);
1186
1187         for (i = 0; i < ubi->fm_wl_pool.size; i++)
1188                 fmpl2->pebs[i] = cpu_to_be32(ubi->fm_wl_pool.pebs[i]);
1189
1190         for (node = rb_first(&ubi->free); node; node = rb_next(node)) {
1191                 wl_e = rb_entry(node, struct ubi_wl_entry, u.rb);
1192                 fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1193
1194                 fec->pnum = cpu_to_be32(wl_e->pnum);
1195                 fec->ec = cpu_to_be32(wl_e->ec);
1196
1197                 free_peb_count++;
1198                 fm_pos += sizeof(*fec);
1199                 ubi_assert(fm_pos <= ubi->fm_size);
1200         }
1201         fmh->free_peb_count = cpu_to_be32(free_peb_count);
1202
1203         for (node = rb_first(&ubi->used); node; node = rb_next(node)) {
1204                 wl_e = rb_entry(node, struct ubi_wl_entry, u.rb);
1205                 fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1206
1207                 fec->pnum = cpu_to_be32(wl_e->pnum);
1208                 fec->ec = cpu_to_be32(wl_e->ec);
1209
1210                 used_peb_count++;
1211                 fm_pos += sizeof(*fec);
1212                 ubi_assert(fm_pos <= ubi->fm_size);
1213         }
1214         fmh->used_peb_count = cpu_to_be32(used_peb_count);
1215
1216         for (node = rb_first(&ubi->scrub); node; node = rb_next(node)) {
1217                 wl_e = rb_entry(node, struct ubi_wl_entry, u.rb);
1218                 fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1219
1220                 fec->pnum = cpu_to_be32(wl_e->pnum);
1221                 fec->ec = cpu_to_be32(wl_e->ec);
1222
1223                 scrub_peb_count++;
1224                 fm_pos += sizeof(*fec);
1225                 ubi_assert(fm_pos <= ubi->fm_size);
1226         }
1227         fmh->scrub_peb_count = cpu_to_be32(scrub_peb_count);
1228
1229
1230         list_for_each_entry(ubi_wrk, &ubi->works, list) {
1231                 if (ubi_is_erase_work(ubi_wrk)) {
1232                         wl_e = ubi_wrk->e;
1233                         ubi_assert(wl_e);
1234
1235                         fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1236
1237                         fec->pnum = cpu_to_be32(wl_e->pnum);
1238                         fec->ec = cpu_to_be32(wl_e->ec);
1239
1240                         erase_peb_count++;
1241                         fm_pos += sizeof(*fec);
1242                         ubi_assert(fm_pos <= ubi->fm_size);
1243                 }
1244         }
1245         fmh->erase_peb_count = cpu_to_be32(erase_peb_count);
1246
1247         for (i = 0; i < UBI_MAX_VOLUMES + UBI_INT_VOL_COUNT; i++) {
1248                 vol = ubi->volumes[i];
1249
1250                 if (!vol)
1251                         continue;
1252
1253                 vol_count++;
1254
1255                 fvh = (struct ubi_fm_volhdr *)(fm_raw + fm_pos);
1256                 fm_pos += sizeof(*fvh);
1257                 ubi_assert(fm_pos <= ubi->fm_size);
1258
1259                 fvh->magic = cpu_to_be32(UBI_FM_VHDR_MAGIC);
1260                 fvh->vol_id = cpu_to_be32(vol->vol_id);
1261                 fvh->vol_type = vol->vol_type;
1262                 fvh->used_ebs = cpu_to_be32(vol->used_ebs);
1263                 fvh->data_pad = cpu_to_be32(vol->data_pad);
1264                 fvh->last_eb_bytes = cpu_to_be32(vol->last_eb_bytes);
1265
1266                 ubi_assert(vol->vol_type == UBI_DYNAMIC_VOLUME ||
1267                         vol->vol_type == UBI_STATIC_VOLUME);
1268
1269                 feba = (struct ubi_fm_eba *)(fm_raw + fm_pos);
1270                 fm_pos += sizeof(*feba) + (sizeof(__be32) * vol->reserved_pebs);
1271                 ubi_assert(fm_pos <= ubi->fm_size);
1272
1273                 for (j = 0; j < vol->reserved_pebs; j++)
1274                         feba->pnum[j] = cpu_to_be32(vol->eba_tbl[j]);
1275
1276                 feba->reserved_pebs = cpu_to_be32(j);
1277                 feba->magic = cpu_to_be32(UBI_FM_EBA_MAGIC);
1278         }
1279         fmh->vol_count = cpu_to_be32(vol_count);
1280         fmh->bad_peb_count = cpu_to_be32(ubi->bad_peb_count);
1281
1282         avhdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1283         avhdr->lnum = 0;
1284
1285         spin_unlock(&ubi->wl_lock);
1286         spin_unlock(&ubi->volumes_lock);
1287
1288         dbg_bld("writing fastmap SB to PEB %i", new_fm->e[0]->pnum);
1289         ret = ubi_io_write_vid_hdr(ubi, new_fm->e[0]->pnum, avhdr);
1290         if (ret) {
1291                 ubi_err("unable to write vid_hdr to fastmap SB!");
1292                 goto out_kfree;
1293         }
1294
1295         for (i = 0; i < new_fm->used_blocks; i++) {
1296                 fmsb->block_loc[i] = cpu_to_be32(new_fm->e[i]->pnum);
1297                 fmsb->block_ec[i] = cpu_to_be32(new_fm->e[i]->ec);
1298         }
1299
1300         fmsb->data_crc = 0;
1301         fmsb->data_crc = cpu_to_be32(crc32(UBI_CRC32_INIT, fm_raw,
1302                                            ubi->fm_size));
1303
1304         for (i = 1; i < new_fm->used_blocks; i++) {
1305                 dvhdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1306                 dvhdr->lnum = cpu_to_be32(i);
1307                 dbg_bld("writing fastmap data to PEB %i sqnum %llu",
1308                         new_fm->e[i]->pnum, be64_to_cpu(dvhdr->sqnum));
1309                 ret = ubi_io_write_vid_hdr(ubi, new_fm->e[i]->pnum, dvhdr);
1310                 if (ret) {
1311                         ubi_err("unable to write vid_hdr to PEB %i!",
1312                                 new_fm->e[i]->pnum);
1313                         goto out_kfree;
1314                 }
1315         }
1316
1317         for (i = 0; i < new_fm->used_blocks; i++) {
1318                 ret = ubi_io_write(ubi, fm_raw + (i * ubi->leb_size),
1319                         new_fm->e[i]->pnum, ubi->leb_start, ubi->leb_size);
1320                 if (ret) {
1321                         ubi_err("unable to write fastmap to PEB %i!",
1322                                 new_fm->e[i]->pnum);
1323                         goto out_kfree;
1324                 }
1325         }
1326
1327         ubi_assert(new_fm);
1328         ubi->fm = new_fm;
1329
1330         dbg_bld("fastmap written!");
1331
1332 out_kfree:
1333         ubi_free_vid_hdr(ubi, avhdr);
1334         ubi_free_vid_hdr(ubi, dvhdr);
1335 out:
1336         return ret;
1337 }
1338
1339 /**
1340  * erase_block - Manually erase a PEB.
1341  * @ubi: UBI device object
1342  * @pnum: PEB to be erased
1343  *
1344  * Returns the new EC value on success, < 0 indicates an internal error.
1345  */
1346 static int erase_block(struct ubi_device *ubi, int pnum)
1347 {
1348         int ret;
1349         struct ubi_ec_hdr *ec_hdr;
1350         long long ec;
1351
1352         ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
1353         if (!ec_hdr)
1354                 return -ENOMEM;
1355
1356         ret = ubi_io_read_ec_hdr(ubi, pnum, ec_hdr, 0);
1357         if (ret < 0)
1358                 goto out;
1359         else if (ret && ret != UBI_IO_BITFLIPS) {
1360                 ret = -EINVAL;
1361                 goto out;
1362         }
1363
1364         ret = ubi_io_sync_erase(ubi, pnum, 0);
1365         if (ret < 0)
1366                 goto out;
1367
1368         ec = be64_to_cpu(ec_hdr->ec);
1369         ec += ret;
1370         if (ec > UBI_MAX_ERASECOUNTER) {
1371                 ret = -EINVAL;
1372                 goto out;
1373         }
1374
1375         ec_hdr->ec = cpu_to_be64(ec);
1376         ret = ubi_io_write_ec_hdr(ubi, pnum, ec_hdr);
1377         if (ret < 0)
1378                 goto out;
1379
1380         ret = ec;
1381 out:
1382         kfree(ec_hdr);
1383         return ret;
1384 }
1385
1386 /**
1387  * invalidate_fastmap - destroys a fastmap.
1388  * @ubi: UBI device object
1389  * @fm: the fastmap to be destroyed
1390  *
1391  * Returns 0 on success, < 0 indicates an internal error.
1392  */
1393 static int invalidate_fastmap(struct ubi_device *ubi,
1394                               struct ubi_fastmap_layout *fm)
1395 {
1396         int ret;
1397         struct ubi_vid_hdr *vh;
1398
1399         ret = erase_block(ubi, fm->e[0]->pnum);
1400         if (ret < 0)
1401                 return ret;
1402
1403         vh = new_fm_vhdr(ubi, UBI_FM_SB_VOLUME_ID);
1404         if (!vh)
1405                 return -ENOMEM;
1406
1407         /* deleting the current fastmap SB is not enough, an old SB may exist,
1408          * so create a (corrupted) SB such that fastmap will find it and fall
1409          * back to scanning mode in any case */
1410         vh->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1411         ret = ubi_io_write_vid_hdr(ubi, fm->e[0]->pnum, vh);
1412
1413         return ret;
1414 }
1415
1416 /**
1417  * ubi_update_fastmap - will be called by UBI if a volume changes or
1418  * a fastmap pool becomes full.
1419  * @ubi: UBI device object
1420  *
1421  * Returns 0 on success, < 0 indicates an internal error.
1422  */
1423 int ubi_update_fastmap(struct ubi_device *ubi)
1424 {
1425         int ret, i;
1426         struct ubi_fastmap_layout *new_fm, *old_fm;
1427         struct ubi_wl_entry *tmp_e;
1428
1429         mutex_lock(&ubi->fm_mutex);
1430
1431         ubi_refill_pools(ubi);
1432
1433         if (ubi->ro_mode || ubi->fm_disabled) {
1434                 mutex_unlock(&ubi->fm_mutex);
1435                 return 0;
1436         }
1437
1438         ret = ubi_ensure_anchor_pebs(ubi);
1439         if (ret) {
1440                 mutex_unlock(&ubi->fm_mutex);
1441                 return ret;
1442         }
1443
1444         new_fm = kzalloc(sizeof(*new_fm), GFP_KERNEL);
1445         if (!new_fm) {
1446                 mutex_unlock(&ubi->fm_mutex);
1447                 return -ENOMEM;
1448         }
1449
1450         new_fm->used_blocks = ubi->fm_size / ubi->leb_size;
1451
1452         for (i = 0; i < new_fm->used_blocks; i++) {
1453                 new_fm->e[i] = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL);
1454                 if (!new_fm->e[i]) {
1455                         while (i--)
1456                                 kfree(new_fm->e[i]);
1457
1458                         kfree(new_fm);
1459                         mutex_unlock(&ubi->fm_mutex);
1460                         return -ENOMEM;
1461                 }
1462         }
1463
1464         old_fm = ubi->fm;
1465         ubi->fm = NULL;
1466
1467         if (new_fm->used_blocks > UBI_FM_MAX_BLOCKS) {
1468                 ubi_err("fastmap too large");
1469                 ret = -ENOSPC;
1470                 goto err;
1471         }
1472
1473         for (i = 1; i < new_fm->used_blocks; i++) {
1474                 spin_lock(&ubi->wl_lock);
1475                 tmp_e = ubi_wl_get_fm_peb(ubi, 0);
1476                 spin_unlock(&ubi->wl_lock);
1477
1478                 if (!tmp_e && !old_fm) {
1479                         int j;
1480                         ubi_err("could not get any free erase block");
1481
1482                         for (j = 1; j < i; j++)
1483                                 ubi_wl_put_fm_peb(ubi, new_fm->e[j], j, 0);
1484
1485                         ret = -ENOSPC;
1486                         goto err;
1487                 } else if (!tmp_e && old_fm) {
1488                         ret = erase_block(ubi, old_fm->e[i]->pnum);
1489                         if (ret < 0) {
1490                                 int j;
1491
1492                                 for (j = 1; j < i; j++)
1493                                         ubi_wl_put_fm_peb(ubi, new_fm->e[j],
1494                                                           j, 0);
1495
1496                                 ubi_err("could not erase old fastmap PEB");
1497                                 goto err;
1498                         }
1499
1500                         new_fm->e[i]->pnum = old_fm->e[i]->pnum;
1501                         new_fm->e[i]->ec = old_fm->e[i]->ec;
1502                 } else {
1503                         new_fm->e[i]->pnum = tmp_e->pnum;
1504                         new_fm->e[i]->ec = tmp_e->ec;
1505
1506                         if (old_fm)
1507                                 ubi_wl_put_fm_peb(ubi, old_fm->e[i], i,
1508                                                   old_fm->to_be_tortured[i]);
1509                 }
1510         }
1511
1512         spin_lock(&ubi->wl_lock);
1513         tmp_e = ubi_wl_get_fm_peb(ubi, 1);
1514         spin_unlock(&ubi->wl_lock);
1515
1516         if (old_fm) {
1517                 /* no fresh anchor PEB was found, reuse the old one */
1518                 if (!tmp_e) {
1519                         ret = erase_block(ubi, old_fm->e[0]->pnum);
1520                         if (ret < 0) {
1521                                 int i;
1522                                 ubi_err("could not erase old anchor PEB");
1523
1524                                 for (i = 1; i < new_fm->used_blocks; i++)
1525                                         ubi_wl_put_fm_peb(ubi, new_fm->e[i],
1526                                                           i, 0);
1527                                 goto err;
1528                         }
1529
1530                         new_fm->e[0]->pnum = old_fm->e[0]->pnum;
1531                         new_fm->e[0]->ec = ret;
1532                 } else {
1533                         /* we've got a new anchor PEB, return the old one */
1534                         ubi_wl_put_fm_peb(ubi, old_fm->e[0], 0,
1535                                           old_fm->to_be_tortured[0]);
1536
1537                         new_fm->e[0]->pnum = tmp_e->pnum;
1538                         new_fm->e[0]->ec = tmp_e->ec;
1539                 }
1540         } else {
1541                 if (!tmp_e) {
1542                         int i;
1543                         ubi_err("could not find any anchor PEB");
1544
1545                         for (i = 1; i < new_fm->used_blocks; i++)
1546                                 ubi_wl_put_fm_peb(ubi, new_fm->e[i], i, 0);
1547
1548                         ret = -ENOSPC;
1549                         goto err;
1550                 }
1551
1552                 new_fm->e[0]->pnum = tmp_e->pnum;
1553                 new_fm->e[0]->ec = tmp_e->ec;
1554         }
1555
1556         down_write(&ubi->work_sem);
1557         down_write(&ubi->fm_sem);
1558         ret = ubi_write_fastmap(ubi, new_fm);
1559         up_write(&ubi->fm_sem);
1560         up_write(&ubi->work_sem);
1561
1562         if (ret)
1563                 goto err;
1564
1565 out_unlock:
1566         mutex_unlock(&ubi->fm_mutex);
1567         kfree(old_fm);
1568         return ret;
1569
1570 err:
1571         kfree(new_fm);
1572
1573         ubi_warn("Unable to write new fastmap, err=%i", ret);
1574
1575         ret = 0;
1576         if (old_fm) {
1577                 ret = invalidate_fastmap(ubi, old_fm);
1578                 if (ret < 0)
1579                         ubi_err("Unable to invalidiate current fastmap!");
1580                 else if (ret)
1581                         ret = 0;
1582         }
1583         goto out_unlock;
1584 }