Commit | Line | Data |
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801c135c AB |
1 | /* |
2 | * Copyright (c) International Business Machines Corp., 2006 | |
3 | * Copyright (c) Nokia Corporation, 2006, 2007 | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License as published by | |
7 | * the Free Software Foundation; either version 2 of the License, or | |
8 | * (at your option) any later version. | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See | |
13 | * the GNU General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License | |
16 | * along with this program; if not, write to the Free Software | |
17 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
18 | * | |
19 | * Author: Artem Bityutskiy (Битюцкий Артём) | |
20 | */ | |
21 | ||
22 | /* | |
23 | * This file includes volume table manipulation code. The volume table is an | |
24 | * on-flash table containing volume meta-data like name, number of reserved | |
25 | * physical eraseblocks, type, etc. The volume table is stored in the so-called | |
26 | * "layout volume". | |
27 | * | |
28 | * The layout volume is an internal volume which is organized as follows. It | |
29 | * consists of two logical eraseblocks - LEB 0 and LEB 1. Each logical | |
30 | * eraseblock stores one volume table copy, i.e. LEB 0 and LEB 1 duplicate each | |
31 | * other. This redundancy guarantees robustness to unclean reboots. The volume | |
32 | * table is basically an array of volume table records. Each record contains | |
33 | * full information about the volume and protected by a CRC checksum. | |
34 | * | |
35 | * The volume table is changed, it is first changed in RAM. Then LEB 0 is | |
36 | * erased, and the updated volume table is written back to LEB 0. Then same for | |
37 | * LEB 1. This scheme guarantees recoverability from unclean reboots. | |
38 | * | |
39 | * In this UBI implementation the on-flash volume table does not contain any | |
40 | * information about how many data static volumes contain. This information may | |
41 | * be found from the scanning data. | |
42 | * | |
43 | * But it would still be beneficial to store this information in the volume | |
44 | * table. For example, suppose we have a static volume X, and all its physical | |
45 | * eraseblocks became bad for some reasons. Suppose we are attaching the | |
46 | * corresponding MTD device, the scanning has found no logical eraseblocks | |
47 | * corresponding to the volume X. According to the volume table volume X does | |
48 | * exist. So we don't know whether it is just empty or all its physical | |
49 | * eraseblocks went bad. So we cannot alarm the user about this corruption. | |
50 | * | |
51 | * The volume table also stores so-called "update marker", which is used for | |
52 | * volume updates. Before updating the volume, the update marker is set, and | |
53 | * after the update operation is finished, the update marker is cleared. So if | |
54 | * the update operation was interrupted (e.g. by an unclean reboot) - the | |
55 | * update marker is still there and we know that the volume's contents is | |
56 | * damaged. | |
57 | */ | |
58 | ||
59 | #include <linux/crc32.h> | |
60 | #include <linux/err.h> | |
5a0e3ad6 | 61 | #include <linux/slab.h> |
801c135c AB |
62 | #include <asm/div64.h> |
63 | #include "ubi.h" | |
64 | ||
92d124f5 | 65 | #ifdef CONFIG_MTD_UBI_DEBUG |
801c135c AB |
66 | static void paranoid_vtbl_check(const struct ubi_device *ubi); |
67 | #else | |
68 | #define paranoid_vtbl_check(ubi) | |
69 | #endif | |
70 | ||
71 | /* Empty volume table record */ | |
72 | static struct ubi_vtbl_record empty_vtbl_record; | |
73 | ||
74 | /** | |
75 | * ubi_change_vtbl_record - change volume table record. | |
76 | * @ubi: UBI device description object | |
77 | * @idx: table index to change | |
78 | * @vtbl_rec: new volume table record | |
79 | * | |
80 | * This function changes volume table record @idx. If @vtbl_rec is %NULL, empty | |
81 | * volume table record is written. The caller does not have to calculate CRC of | |
82 | * the record as it is done by this function. Returns zero in case of success | |
83 | * and a negative error code in case of failure. | |
84 | */ | |
85 | int ubi_change_vtbl_record(struct ubi_device *ubi, int idx, | |
86 | struct ubi_vtbl_record *vtbl_rec) | |
87 | { | |
88 | int i, err; | |
89 | uint32_t crc; | |
89b96b69 | 90 | struct ubi_volume *layout_vol; |
801c135c AB |
91 | |
92 | ubi_assert(idx >= 0 && idx < ubi->vtbl_slots); | |
91f2d53c | 93 | layout_vol = ubi->volumes[vol_id2idx(ubi, UBI_LAYOUT_VOLUME_ID)]; |
801c135c AB |
94 | |
95 | if (!vtbl_rec) | |
96 | vtbl_rec = &empty_vtbl_record; | |
97 | else { | |
98 | crc = crc32(UBI_CRC32_INIT, vtbl_rec, UBI_VTBL_RECORD_SIZE_CRC); | |
3261ebd7 | 99 | vtbl_rec->crc = cpu_to_be32(crc); |
801c135c AB |
100 | } |
101 | ||
801c135c AB |
102 | memcpy(&ubi->vtbl[idx], vtbl_rec, sizeof(struct ubi_vtbl_record)); |
103 | for (i = 0; i < UBI_LAYOUT_VOLUME_EBS; i++) { | |
89b96b69 | 104 | err = ubi_eba_unmap_leb(ubi, layout_vol, i); |
cae0a771 | 105 | if (err) |
801c135c | 106 | return err; |
cae0a771 | 107 | |
89b96b69 | 108 | err = ubi_eba_write_leb(ubi, layout_vol, i, ubi->vtbl, 0, |
801c135c | 109 | ubi->vtbl_size, UBI_LONGTERM); |
cae0a771 | 110 | if (err) |
801c135c | 111 | return err; |
801c135c AB |
112 | } |
113 | ||
114 | paranoid_vtbl_check(ubi); | |
6dc4a871 | 115 | return 0; |
801c135c AB |
116 | } |
117 | ||
f40ac9cd AB |
118 | /** |
119 | * ubi_vtbl_rename_volumes - rename UBI volumes in the volume table. | |
120 | * @ubi: UBI device description object | |
ebaaf1af | 121 | * @rename_list: list of &struct ubi_rename_entry objects |
f40ac9cd AB |
122 | * |
123 | * This function re-names multiple volumes specified in @req in the volume | |
124 | * table. Returns zero in case of success and a negative error code in case of | |
125 | * failure. | |
126 | */ | |
127 | int ubi_vtbl_rename_volumes(struct ubi_device *ubi, | |
128 | struct list_head *rename_list) | |
129 | { | |
130 | int i, err; | |
131 | struct ubi_rename_entry *re; | |
132 | struct ubi_volume *layout_vol; | |
133 | ||
134 | list_for_each_entry(re, rename_list, list) { | |
135 | uint32_t crc; | |
136 | struct ubi_volume *vol = re->desc->vol; | |
137 | struct ubi_vtbl_record *vtbl_rec = &ubi->vtbl[vol->vol_id]; | |
138 | ||
139 | if (re->remove) { | |
140 | memcpy(vtbl_rec, &empty_vtbl_record, | |
141 | sizeof(struct ubi_vtbl_record)); | |
142 | continue; | |
143 | } | |
144 | ||
145 | vtbl_rec->name_len = cpu_to_be16(re->new_name_len); | |
146 | memcpy(vtbl_rec->name, re->new_name, re->new_name_len); | |
147 | memset(vtbl_rec->name + re->new_name_len, 0, | |
148 | UBI_VOL_NAME_MAX + 1 - re->new_name_len); | |
149 | crc = crc32(UBI_CRC32_INIT, vtbl_rec, | |
150 | UBI_VTBL_RECORD_SIZE_CRC); | |
151 | vtbl_rec->crc = cpu_to_be32(crc); | |
152 | } | |
153 | ||
154 | layout_vol = ubi->volumes[vol_id2idx(ubi, UBI_LAYOUT_VOLUME_ID)]; | |
155 | for (i = 0; i < UBI_LAYOUT_VOLUME_EBS; i++) { | |
156 | err = ubi_eba_unmap_leb(ubi, layout_vol, i); | |
157 | if (err) | |
158 | return err; | |
159 | ||
160 | err = ubi_eba_write_leb(ubi, layout_vol, i, ubi->vtbl, 0, | |
161 | ubi->vtbl_size, UBI_LONGTERM); | |
162 | if (err) | |
163 | return err; | |
164 | } | |
165 | ||
166 | return 0; | |
167 | } | |
168 | ||
801c135c | 169 | /** |
ebaaf1af | 170 | * vtbl_check - check if volume table is not corrupted and sensible. |
801c135c AB |
171 | * @ubi: UBI device description object |
172 | * @vtbl: volume table | |
173 | * | |
174 | * This function returns zero if @vtbl is all right, %1 if CRC is incorrect, | |
175 | * and %-EINVAL if it contains inconsistent data. | |
176 | */ | |
177 | static int vtbl_check(const struct ubi_device *ubi, | |
178 | const struct ubi_vtbl_record *vtbl) | |
179 | { | |
180 | int i, n, reserved_pebs, alignment, data_pad, vol_type, name_len; | |
979c9296 | 181 | int upd_marker, err; |
801c135c AB |
182 | uint32_t crc; |
183 | const char *name; | |
184 | ||
185 | for (i = 0; i < ubi->vtbl_slots; i++) { | |
186 | cond_resched(); | |
187 | ||
3261ebd7 CH |
188 | reserved_pebs = be32_to_cpu(vtbl[i].reserved_pebs); |
189 | alignment = be32_to_cpu(vtbl[i].alignment); | |
190 | data_pad = be32_to_cpu(vtbl[i].data_pad); | |
801c135c AB |
191 | upd_marker = vtbl[i].upd_marker; |
192 | vol_type = vtbl[i].vol_type; | |
3261ebd7 | 193 | name_len = be16_to_cpu(vtbl[i].name_len); |
801c135c AB |
194 | name = &vtbl[i].name[0]; |
195 | ||
196 | crc = crc32(UBI_CRC32_INIT, &vtbl[i], UBI_VTBL_RECORD_SIZE_CRC); | |
3261ebd7 | 197 | if (be32_to_cpu(vtbl[i].crc) != crc) { |
801c135c | 198 | ubi_err("bad CRC at record %u: %#08x, not %#08x", |
3261ebd7 | 199 | i, crc, be32_to_cpu(vtbl[i].crc)); |
801c135c AB |
200 | ubi_dbg_dump_vtbl_record(&vtbl[i], i); |
201 | return 1; | |
202 | } | |
203 | ||
204 | if (reserved_pebs == 0) { | |
205 | if (memcmp(&vtbl[i], &empty_vtbl_record, | |
206 | UBI_VTBL_RECORD_SIZE)) { | |
979c9296 | 207 | err = 2; |
801c135c AB |
208 | goto bad; |
209 | } | |
210 | continue; | |
211 | } | |
212 | ||
213 | if (reserved_pebs < 0 || alignment < 0 || data_pad < 0 || | |
214 | name_len < 0) { | |
979c9296 | 215 | err = 3; |
801c135c AB |
216 | goto bad; |
217 | } | |
218 | ||
219 | if (alignment > ubi->leb_size || alignment == 0) { | |
979c9296 | 220 | err = 4; |
801c135c AB |
221 | goto bad; |
222 | } | |
223 | ||
cadb40cc | 224 | n = alignment & (ubi->min_io_size - 1); |
801c135c | 225 | if (alignment != 1 && n) { |
979c9296 | 226 | err = 5; |
801c135c AB |
227 | goto bad; |
228 | } | |
229 | ||
230 | n = ubi->leb_size % alignment; | |
231 | if (data_pad != n) { | |
232 | dbg_err("bad data_pad, has to be %d", n); | |
979c9296 | 233 | err = 6; |
801c135c AB |
234 | goto bad; |
235 | } | |
236 | ||
237 | if (vol_type != UBI_VID_DYNAMIC && vol_type != UBI_VID_STATIC) { | |
979c9296 | 238 | err = 7; |
801c135c AB |
239 | goto bad; |
240 | } | |
241 | ||
242 | if (upd_marker != 0 && upd_marker != 1) { | |
979c9296 | 243 | err = 8; |
801c135c AB |
244 | goto bad; |
245 | } | |
246 | ||
247 | if (reserved_pebs > ubi->good_peb_count) { | |
762a9f29 DS |
248 | dbg_err("too large reserved_pebs %d, good PEBs %d", |
249 | reserved_pebs, ubi->good_peb_count); | |
979c9296 | 250 | err = 9; |
801c135c AB |
251 | goto bad; |
252 | } | |
253 | ||
254 | if (name_len > UBI_VOL_NAME_MAX) { | |
979c9296 | 255 | err = 10; |
801c135c AB |
256 | goto bad; |
257 | } | |
258 | ||
259 | if (name[0] == '\0') { | |
979c9296 | 260 | err = 11; |
801c135c AB |
261 | goto bad; |
262 | } | |
263 | ||
264 | if (name_len != strnlen(name, name_len + 1)) { | |
979c9296 | 265 | err = 12; |
801c135c AB |
266 | goto bad; |
267 | } | |
268 | } | |
269 | ||
270 | /* Checks that all names are unique */ | |
271 | for (i = 0; i < ubi->vtbl_slots - 1; i++) { | |
272 | for (n = i + 1; n < ubi->vtbl_slots; n++) { | |
3261ebd7 CH |
273 | int len1 = be16_to_cpu(vtbl[i].name_len); |
274 | int len2 = be16_to_cpu(vtbl[n].name_len); | |
801c135c AB |
275 | |
276 | if (len1 > 0 && len1 == len2 && | |
277 | !strncmp(vtbl[i].name, vtbl[n].name, len1)) { | |
278 | ubi_err("volumes %d and %d have the same name" | |
279 | " \"%s\"", i, n, vtbl[i].name); | |
280 | ubi_dbg_dump_vtbl_record(&vtbl[i], i); | |
281 | ubi_dbg_dump_vtbl_record(&vtbl[n], n); | |
282 | return -EINVAL; | |
283 | } | |
284 | } | |
285 | } | |
286 | ||
287 | return 0; | |
288 | ||
289 | bad: | |
979c9296 | 290 | ubi_err("volume table check failed: record %d, error %d", i, err); |
801c135c AB |
291 | ubi_dbg_dump_vtbl_record(&vtbl[i], i); |
292 | return -EINVAL; | |
293 | } | |
294 | ||
295 | /** | |
296 | * create_vtbl - create a copy of volume table. | |
297 | * @ubi: UBI device description object | |
298 | * @si: scanning information | |
299 | * @copy: number of the volume table copy | |
300 | * @vtbl: contents of the volume table | |
301 | * | |
302 | * This function returns zero in case of success and a negative error code in | |
303 | * case of failure. | |
304 | */ | |
e88d6e10 | 305 | static int create_vtbl(struct ubi_device *ubi, struct ubi_scan_info *si, |
801c135c AB |
306 | int copy, void *vtbl) |
307 | { | |
308 | int err, tries = 0; | |
309 | static struct ubi_vid_hdr *vid_hdr; | |
310 | struct ubi_scan_volume *sv; | |
311 | struct ubi_scan_leb *new_seb, *old_seb = NULL; | |
312 | ||
313 | ubi_msg("create volume table (copy #%d)", copy + 1); | |
314 | ||
33818bbb | 315 | vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL); |
801c135c AB |
316 | if (!vid_hdr) |
317 | return -ENOMEM; | |
318 | ||
319 | /* | |
320 | * Check if there is a logical eraseblock which would have to contain | |
321 | * this volume table copy was found during scanning. It has to be wiped | |
322 | * out. | |
323 | */ | |
91f2d53c | 324 | sv = ubi_scan_find_sv(si, UBI_LAYOUT_VOLUME_ID); |
801c135c AB |
325 | if (sv) |
326 | old_seb = ubi_scan_find_seb(sv, copy); | |
327 | ||
328 | retry: | |
329 | new_seb = ubi_scan_get_free_peb(ubi, si); | |
330 | if (IS_ERR(new_seb)) { | |
331 | err = PTR_ERR(new_seb); | |
332 | goto out_free; | |
333 | } | |
334 | ||
335 | vid_hdr->vol_type = UBI_VID_DYNAMIC; | |
91f2d53c | 336 | vid_hdr->vol_id = cpu_to_be32(UBI_LAYOUT_VOLUME_ID); |
801c135c AB |
337 | vid_hdr->compat = UBI_LAYOUT_VOLUME_COMPAT; |
338 | vid_hdr->data_size = vid_hdr->used_ebs = | |
3261ebd7 CH |
339 | vid_hdr->data_pad = cpu_to_be32(0); |
340 | vid_hdr->lnum = cpu_to_be32(copy); | |
341 | vid_hdr->sqnum = cpu_to_be64(++si->max_sqnum); | |
801c135c AB |
342 | |
343 | /* The EC header is already there, write the VID header */ | |
344 | err = ubi_io_write_vid_hdr(ubi, new_seb->pnum, vid_hdr); | |
345 | if (err) | |
346 | goto write_error; | |
347 | ||
348 | /* Write the layout volume contents */ | |
349 | err = ubi_io_write_data(ubi, vtbl, new_seb->pnum, 0, ubi->vtbl_size); | |
350 | if (err) | |
351 | goto write_error; | |
352 | ||
353 | /* | |
354 | * And add it to the scanning information. Don't delete the old | |
355 | * @old_seb as it will be deleted and freed in 'ubi_scan_add_used()'. | |
356 | */ | |
357 | err = ubi_scan_add_used(ubi, si, new_seb->pnum, new_seb->ec, | |
358 | vid_hdr, 0); | |
359 | kfree(new_seb); | |
360 | ubi_free_vid_hdr(ubi, vid_hdr); | |
361 | return err; | |
362 | ||
363 | write_error: | |
78d87c95 AB |
364 | if (err == -EIO && ++tries <= 5) { |
365 | /* | |
366 | * Probably this physical eraseblock went bad, try to pick | |
367 | * another one. | |
368 | */ | |
0525dac9 | 369 | list_add(&new_seb->u.list, &si->erase); |
c4e90ec0 | 370 | goto retry; |
78d87c95 AB |
371 | } |
372 | kfree(new_seb); | |
801c135c AB |
373 | out_free: |
374 | ubi_free_vid_hdr(ubi, vid_hdr); | |
375 | return err; | |
376 | ||
377 | } | |
378 | ||
379 | /** | |
380 | * process_lvol - process the layout volume. | |
381 | * @ubi: UBI device description object | |
382 | * @si: scanning information | |
383 | * @sv: layout volume scanning information | |
384 | * | |
385 | * This function is responsible for reading the layout volume, ensuring it is | |
386 | * not corrupted, and recovering from corruptions if needed. Returns volume | |
387 | * table in case of success and a negative error code in case of failure. | |
388 | */ | |
e88d6e10 | 389 | static struct ubi_vtbl_record *process_lvol(struct ubi_device *ubi, |
801c135c AB |
390 | struct ubi_scan_info *si, |
391 | struct ubi_scan_volume *sv) | |
392 | { | |
393 | int err; | |
394 | struct rb_node *rb; | |
395 | struct ubi_scan_leb *seb; | |
396 | struct ubi_vtbl_record *leb[UBI_LAYOUT_VOLUME_EBS] = { NULL, NULL }; | |
397 | int leb_corrupted[UBI_LAYOUT_VOLUME_EBS] = {1, 1}; | |
398 | ||
399 | /* | |
400 | * UBI goes through the following steps when it changes the layout | |
401 | * volume: | |
402 | * a. erase LEB 0; | |
403 | * b. write new data to LEB 0; | |
404 | * c. erase LEB 1; | |
405 | * d. write new data to LEB 1. | |
406 | * | |
407 | * Before the change, both LEBs contain the same data. | |
408 | * | |
409 | * Due to unclean reboots, the contents of LEB 0 may be lost, but there | |
410 | * should LEB 1. So it is OK if LEB 0 is corrupted while LEB 1 is not. | |
411 | * Similarly, LEB 1 may be lost, but there should be LEB 0. And | |
412 | * finally, unclean reboots may result in a situation when neither LEB | |
413 | * 0 nor LEB 1 are corrupted, but they are different. In this case, LEB | |
414 | * 0 contains more recent information. | |
415 | * | |
416 | * So the plan is to first check LEB 0. Then | |
be436f62 | 417 | * a. if LEB 0 is OK, it must be containing the most recent data; then |
801c135c AB |
418 | * we compare it with LEB 1, and if they are different, we copy LEB |
419 | * 0 to LEB 1; | |
420 | * b. if LEB 0 is corrupted, but LEB 1 has to be OK, and we copy LEB 1 | |
421 | * to LEB 0. | |
422 | */ | |
423 | ||
c8566350 | 424 | dbg_gen("check layout volume"); |
801c135c AB |
425 | |
426 | /* Read both LEB 0 and LEB 1 into memory */ | |
427 | ubi_rb_for_each_entry(rb, seb, &sv->root, u.rb) { | |
92ad8f37 | 428 | leb[seb->lnum] = vmalloc(ubi->vtbl_size); |
801c135c AB |
429 | if (!leb[seb->lnum]) { |
430 | err = -ENOMEM; | |
431 | goto out_free; | |
432 | } | |
92ad8f37 | 433 | memset(leb[seb->lnum], 0, ubi->vtbl_size); |
801c135c AB |
434 | |
435 | err = ubi_io_read_data(ubi, leb[seb->lnum], seb->pnum, 0, | |
436 | ubi->vtbl_size); | |
437 | if (err == UBI_IO_BITFLIPS || err == -EBADMSG) | |
beeea636 AB |
438 | /* |
439 | * Scrub the PEB later. Note, -EBADMSG indicates an | |
440 | * uncorrectable ECC error, but we have our own CRC and | |
441 | * the data will be checked later. If the data is OK, | |
442 | * the PEB will be scrubbed (because we set | |
443 | * seb->scrub). If the data is not OK, the contents of | |
444 | * the PEB will be recovered from the second copy, and | |
445 | * seb->scrub will be cleared in | |
446 | * 'ubi_scan_add_used()'. | |
447 | */ | |
801c135c AB |
448 | seb->scrub = 1; |
449 | else if (err) | |
450 | goto out_free; | |
451 | } | |
452 | ||
453 | err = -EINVAL; | |
454 | if (leb[0]) { | |
455 | leb_corrupted[0] = vtbl_check(ubi, leb[0]); | |
456 | if (leb_corrupted[0] < 0) | |
457 | goto out_free; | |
458 | } | |
459 | ||
460 | if (!leb_corrupted[0]) { | |
461 | /* LEB 0 is OK */ | |
462 | if (leb[1]) | |
9c9ec147 AB |
463 | leb_corrupted[1] = memcmp(leb[0], leb[1], |
464 | ubi->vtbl_size); | |
801c135c AB |
465 | if (leb_corrupted[1]) { |
466 | ubi_warn("volume table copy #2 is corrupted"); | |
467 | err = create_vtbl(ubi, si, 1, leb[0]); | |
468 | if (err) | |
469 | goto out_free; | |
470 | ubi_msg("volume table was restored"); | |
471 | } | |
472 | ||
473 | /* Both LEB 1 and LEB 2 are OK and consistent */ | |
92ad8f37 | 474 | vfree(leb[1]); |
801c135c AB |
475 | return leb[0]; |
476 | } else { | |
477 | /* LEB 0 is corrupted or does not exist */ | |
478 | if (leb[1]) { | |
479 | leb_corrupted[1] = vtbl_check(ubi, leb[1]); | |
480 | if (leb_corrupted[1] < 0) | |
481 | goto out_free; | |
482 | } | |
483 | if (leb_corrupted[1]) { | |
484 | /* Both LEB 0 and LEB 1 are corrupted */ | |
485 | ubi_err("both volume tables are corrupted"); | |
486 | goto out_free; | |
487 | } | |
488 | ||
489 | ubi_warn("volume table copy #1 is corrupted"); | |
490 | err = create_vtbl(ubi, si, 0, leb[1]); | |
491 | if (err) | |
492 | goto out_free; | |
493 | ubi_msg("volume table was restored"); | |
494 | ||
92ad8f37 | 495 | vfree(leb[0]); |
801c135c AB |
496 | return leb[1]; |
497 | } | |
498 | ||
499 | out_free: | |
92ad8f37 AB |
500 | vfree(leb[0]); |
501 | vfree(leb[1]); | |
801c135c AB |
502 | return ERR_PTR(err); |
503 | } | |
504 | ||
505 | /** | |
506 | * create_empty_lvol - create empty layout volume. | |
507 | * @ubi: UBI device description object | |
508 | * @si: scanning information | |
509 | * | |
510 | * This function returns volume table contents in case of success and a | |
511 | * negative error code in case of failure. | |
512 | */ | |
e88d6e10 | 513 | static struct ubi_vtbl_record *create_empty_lvol(struct ubi_device *ubi, |
801c135c AB |
514 | struct ubi_scan_info *si) |
515 | { | |
516 | int i; | |
517 | struct ubi_vtbl_record *vtbl; | |
518 | ||
92ad8f37 | 519 | vtbl = vmalloc(ubi->vtbl_size); |
801c135c AB |
520 | if (!vtbl) |
521 | return ERR_PTR(-ENOMEM); | |
92ad8f37 | 522 | memset(vtbl, 0, ubi->vtbl_size); |
801c135c AB |
523 | |
524 | for (i = 0; i < ubi->vtbl_slots; i++) | |
525 | memcpy(&vtbl[i], &empty_vtbl_record, UBI_VTBL_RECORD_SIZE); | |
526 | ||
527 | for (i = 0; i < UBI_LAYOUT_VOLUME_EBS; i++) { | |
528 | int err; | |
529 | ||
530 | err = create_vtbl(ubi, si, i, vtbl); | |
531 | if (err) { | |
92ad8f37 | 532 | vfree(vtbl); |
801c135c AB |
533 | return ERR_PTR(err); |
534 | } | |
535 | } | |
536 | ||
537 | return vtbl; | |
538 | } | |
539 | ||
540 | /** | |
541 | * init_volumes - initialize volume information for existing volumes. | |
542 | * @ubi: UBI device description object | |
543 | * @si: scanning information | |
544 | * @vtbl: volume table | |
545 | * | |
546 | * This function allocates volume description objects for existing volumes. | |
547 | * Returns zero in case of success and a negative error code in case of | |
548 | * failure. | |
549 | */ | |
550 | static int init_volumes(struct ubi_device *ubi, const struct ubi_scan_info *si, | |
551 | const struct ubi_vtbl_record *vtbl) | |
552 | { | |
553 | int i, reserved_pebs = 0; | |
554 | struct ubi_scan_volume *sv; | |
555 | struct ubi_volume *vol; | |
556 | ||
557 | for (i = 0; i < ubi->vtbl_slots; i++) { | |
558 | cond_resched(); | |
559 | ||
3261ebd7 | 560 | if (be32_to_cpu(vtbl[i].reserved_pebs) == 0) |
801c135c AB |
561 | continue; /* Empty record */ |
562 | ||
563 | vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL); | |
564 | if (!vol) | |
565 | return -ENOMEM; | |
566 | ||
3261ebd7 CH |
567 | vol->reserved_pebs = be32_to_cpu(vtbl[i].reserved_pebs); |
568 | vol->alignment = be32_to_cpu(vtbl[i].alignment); | |
569 | vol->data_pad = be32_to_cpu(vtbl[i].data_pad); | |
ff998793 | 570 | vol->upd_marker = vtbl[i].upd_marker; |
801c135c AB |
571 | vol->vol_type = vtbl[i].vol_type == UBI_VID_DYNAMIC ? |
572 | UBI_DYNAMIC_VOLUME : UBI_STATIC_VOLUME; | |
3261ebd7 | 573 | vol->name_len = be16_to_cpu(vtbl[i].name_len); |
801c135c AB |
574 | vol->usable_leb_size = ubi->leb_size - vol->data_pad; |
575 | memcpy(vol->name, vtbl[i].name, vol->name_len); | |
576 | vol->name[vol->name_len] = '\0'; | |
577 | vol->vol_id = i; | |
578 | ||
4ccf8cff AB |
579 | if (vtbl[i].flags & UBI_VTBL_AUTORESIZE_FLG) { |
580 | /* Auto re-size flag may be set only for one volume */ | |
581 | if (ubi->autoresize_vol_id != -1) { | |
025dfdaf | 582 | ubi_err("more than one auto-resize volume (%d " |
4ccf8cff | 583 | "and %d)", ubi->autoresize_vol_id, i); |
f7f02837 | 584 | kfree(vol); |
4ccf8cff AB |
585 | return -EINVAL; |
586 | } | |
587 | ||
588 | ubi->autoresize_vol_id = i; | |
589 | } | |
590 | ||
801c135c AB |
591 | ubi_assert(!ubi->volumes[i]); |
592 | ubi->volumes[i] = vol; | |
593 | ubi->vol_count += 1; | |
594 | vol->ubi = ubi; | |
595 | reserved_pebs += vol->reserved_pebs; | |
596 | ||
597 | /* | |
598 | * In case of dynamic volume UBI knows nothing about how many | |
599 | * data is stored there. So assume the whole volume is used. | |
600 | */ | |
601 | if (vol->vol_type == UBI_DYNAMIC_VOLUME) { | |
602 | vol->used_ebs = vol->reserved_pebs; | |
603 | vol->last_eb_bytes = vol->usable_leb_size; | |
d08c3b78 VA |
604 | vol->used_bytes = |
605 | (long long)vol->used_ebs * vol->usable_leb_size; | |
801c135c AB |
606 | continue; |
607 | } | |
608 | ||
609 | /* Static volumes only */ | |
610 | sv = ubi_scan_find_sv(si, i); | |
611 | if (!sv) { | |
612 | /* | |
613 | * No eraseblocks belonging to this volume found. We | |
614 | * don't actually know whether this static volume is | |
615 | * completely corrupted or just contains no data. And | |
616 | * we cannot know this as long as data size is not | |
617 | * stored on flash. So we just assume the volume is | |
618 | * empty. FIXME: this should be handled. | |
619 | */ | |
620 | continue; | |
621 | } | |
622 | ||
623 | if (sv->leb_count != sv->used_ebs) { | |
624 | /* | |
625 | * We found a static volume which misses several | |
626 | * eraseblocks. Treat it as corrupted. | |
627 | */ | |
628 | ubi_warn("static volume %d misses %d LEBs - corrupted", | |
629 | sv->vol_id, sv->used_ebs - sv->leb_count); | |
630 | vol->corrupted = 1; | |
631 | continue; | |
632 | } | |
633 | ||
634 | vol->used_ebs = sv->used_ebs; | |
d08c3b78 VA |
635 | vol->used_bytes = |
636 | (long long)(vol->used_ebs - 1) * vol->usable_leb_size; | |
801c135c AB |
637 | vol->used_bytes += sv->last_data_size; |
638 | vol->last_eb_bytes = sv->last_data_size; | |
639 | } | |
640 | ||
d05c77a8 | 641 | /* And add the layout volume */ |
801c135c AB |
642 | vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL); |
643 | if (!vol) | |
644 | return -ENOMEM; | |
645 | ||
646 | vol->reserved_pebs = UBI_LAYOUT_VOLUME_EBS; | |
647 | vol->alignment = 1; | |
648 | vol->vol_type = UBI_DYNAMIC_VOLUME; | |
649 | vol->name_len = sizeof(UBI_LAYOUT_VOLUME_NAME) - 1; | |
650 | memcpy(vol->name, UBI_LAYOUT_VOLUME_NAME, vol->name_len + 1); | |
651 | vol->usable_leb_size = ubi->leb_size; | |
652 | vol->used_ebs = vol->reserved_pebs; | |
653 | vol->last_eb_bytes = vol->reserved_pebs; | |
d08c3b78 VA |
654 | vol->used_bytes = |
655 | (long long)vol->used_ebs * (ubi->leb_size - vol->data_pad); | |
91f2d53c | 656 | vol->vol_id = UBI_LAYOUT_VOLUME_ID; |
d05c77a8 | 657 | vol->ref_count = 1; |
801c135c AB |
658 | |
659 | ubi_assert(!ubi->volumes[i]); | |
660 | ubi->volumes[vol_id2idx(ubi, vol->vol_id)] = vol; | |
661 | reserved_pebs += vol->reserved_pebs; | |
662 | ubi->vol_count += 1; | |
663 | vol->ubi = ubi; | |
664 | ||
5fc01ab6 | 665 | if (reserved_pebs > ubi->avail_pebs) { |
801c135c AB |
666 | ubi_err("not enough PEBs, required %d, available %d", |
667 | reserved_pebs, ubi->avail_pebs); | |
5fc01ab6 AB |
668 | if (ubi->corr_peb_count) |
669 | ubi_err("%d PEBs are corrupted and not used", | |
670 | ubi->corr_peb_count); | |
671 | } | |
801c135c AB |
672 | ubi->rsvd_pebs += reserved_pebs; |
673 | ubi->avail_pebs -= reserved_pebs; | |
674 | ||
675 | return 0; | |
676 | } | |
677 | ||
678 | /** | |
679 | * check_sv - check volume scanning information. | |
680 | * @vol: UBI volume description object | |
681 | * @sv: volume scanning information | |
682 | * | |
683 | * This function returns zero if the volume scanning information is consistent | |
684 | * to the data read from the volume tabla, and %-EINVAL if not. | |
685 | */ | |
686 | static int check_sv(const struct ubi_volume *vol, | |
687 | const struct ubi_scan_volume *sv) | |
688 | { | |
979c9296 AB |
689 | int err; |
690 | ||
801c135c | 691 | if (sv->highest_lnum >= vol->reserved_pebs) { |
979c9296 | 692 | err = 1; |
801c135c AB |
693 | goto bad; |
694 | } | |
695 | if (sv->leb_count > vol->reserved_pebs) { | |
979c9296 | 696 | err = 2; |
801c135c AB |
697 | goto bad; |
698 | } | |
699 | if (sv->vol_type != vol->vol_type) { | |
979c9296 | 700 | err = 3; |
801c135c AB |
701 | goto bad; |
702 | } | |
703 | if (sv->used_ebs > vol->reserved_pebs) { | |
979c9296 | 704 | err = 4; |
801c135c AB |
705 | goto bad; |
706 | } | |
707 | if (sv->data_pad != vol->data_pad) { | |
979c9296 | 708 | err = 5; |
801c135c AB |
709 | goto bad; |
710 | } | |
711 | return 0; | |
712 | ||
713 | bad: | |
979c9296 | 714 | ubi_err("bad scanning information, error %d", err); |
801c135c AB |
715 | ubi_dbg_dump_sv(sv); |
716 | ubi_dbg_dump_vol_info(vol); | |
717 | return -EINVAL; | |
718 | } | |
719 | ||
720 | /** | |
721 | * check_scanning_info - check that scanning information. | |
722 | * @ubi: UBI device description object | |
723 | * @si: scanning information | |
724 | * | |
725 | * Even though we protect on-flash data by CRC checksums, we still don't trust | |
726 | * the media. This function ensures that scanning information is consistent to | |
727 | * the information read from the volume table. Returns zero if the scanning | |
728 | * information is OK and %-EINVAL if it is not. | |
729 | */ | |
730 | static int check_scanning_info(const struct ubi_device *ubi, | |
731 | struct ubi_scan_info *si) | |
732 | { | |
733 | int err, i; | |
734 | struct ubi_scan_volume *sv; | |
735 | struct ubi_volume *vol; | |
736 | ||
737 | if (si->vols_found > UBI_INT_VOL_COUNT + ubi->vtbl_slots) { | |
738 | ubi_err("scanning found %d volumes, maximum is %d + %d", | |
739 | si->vols_found, UBI_INT_VOL_COUNT, ubi->vtbl_slots); | |
740 | return -EINVAL; | |
741 | } | |
742 | ||
cadb40cc | 743 | if (si->highest_vol_id >= ubi->vtbl_slots + UBI_INT_VOL_COUNT && |
801c135c AB |
744 | si->highest_vol_id < UBI_INTERNAL_VOL_START) { |
745 | ubi_err("too large volume ID %d found by scanning", | |
746 | si->highest_vol_id); | |
747 | return -EINVAL; | |
748 | } | |
749 | ||
801c135c AB |
750 | for (i = 0; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) { |
751 | cond_resched(); | |
752 | ||
753 | sv = ubi_scan_find_sv(si, i); | |
754 | vol = ubi->volumes[i]; | |
755 | if (!vol) { | |
756 | if (sv) | |
757 | ubi_scan_rm_volume(si, sv); | |
758 | continue; | |
759 | } | |
760 | ||
761 | if (vol->reserved_pebs == 0) { | |
762 | ubi_assert(i < ubi->vtbl_slots); | |
763 | ||
764 | if (!sv) | |
765 | continue; | |
766 | ||
767 | /* | |
768 | * During scanning we found a volume which does not | |
769 | * exist according to the information in the volume | |
770 | * table. This must have happened due to an unclean | |
771 | * reboot while the volume was being removed. Discard | |
772 | * these eraseblocks. | |
773 | */ | |
774 | ubi_msg("finish volume %d removal", sv->vol_id); | |
775 | ubi_scan_rm_volume(si, sv); | |
776 | } else if (sv) { | |
777 | err = check_sv(vol, sv); | |
778 | if (err) | |
779 | return err; | |
780 | } | |
781 | } | |
782 | ||
783 | return 0; | |
784 | } | |
785 | ||
786 | /** | |
ebaaf1af | 787 | * ubi_read_volume_table - read the volume table. |
801c135c AB |
788 | * @ubi: UBI device description object |
789 | * @si: scanning information | |
790 | * | |
791 | * This function reads volume table, checks it, recover from errors if needed, | |
792 | * or creates it if needed. Returns zero in case of success and a negative | |
793 | * error code in case of failure. | |
794 | */ | |
795 | int ubi_read_volume_table(struct ubi_device *ubi, struct ubi_scan_info *si) | |
796 | { | |
797 | int i, err; | |
798 | struct ubi_scan_volume *sv; | |
799 | ||
3261ebd7 | 800 | empty_vtbl_record.crc = cpu_to_be32(0xf116c36b); |
801c135c AB |
801 | |
802 | /* | |
803 | * The number of supported volumes is limited by the eraseblock size | |
804 | * and by the UBI_MAX_VOLUMES constant. | |
805 | */ | |
806 | ubi->vtbl_slots = ubi->leb_size / UBI_VTBL_RECORD_SIZE; | |
807 | if (ubi->vtbl_slots > UBI_MAX_VOLUMES) | |
808 | ubi->vtbl_slots = UBI_MAX_VOLUMES; | |
809 | ||
810 | ubi->vtbl_size = ubi->vtbl_slots * UBI_VTBL_RECORD_SIZE; | |
811 | ubi->vtbl_size = ALIGN(ubi->vtbl_size, ubi->min_io_size); | |
812 | ||
91f2d53c | 813 | sv = ubi_scan_find_sv(si, UBI_LAYOUT_VOLUME_ID); |
801c135c AB |
814 | if (!sv) { |
815 | /* | |
816 | * No logical eraseblocks belonging to the layout volume were | |
817 | * found. This could mean that the flash is just empty. In | |
818 | * this case we create empty layout volume. | |
819 | * | |
820 | * But if flash is not empty this must be a corruption or the | |
821 | * MTD device just contains garbage. | |
822 | */ | |
823 | if (si->is_empty) { | |
824 | ubi->vtbl = create_empty_lvol(ubi, si); | |
825 | if (IS_ERR(ubi->vtbl)) | |
826 | return PTR_ERR(ubi->vtbl); | |
827 | } else { | |
828 | ubi_err("the layout volume was not found"); | |
829 | return -EINVAL; | |
830 | } | |
831 | } else { | |
832 | if (sv->leb_count > UBI_LAYOUT_VOLUME_EBS) { | |
833 | /* This must not happen with proper UBI images */ | |
834 | dbg_err("too many LEBs (%d) in layout volume", | |
835 | sv->leb_count); | |
836 | return -EINVAL; | |
837 | } | |
838 | ||
839 | ubi->vtbl = process_lvol(ubi, si, sv); | |
840 | if (IS_ERR(ubi->vtbl)) | |
841 | return PTR_ERR(ubi->vtbl); | |
842 | } | |
843 | ||
5fc01ab6 | 844 | ubi->avail_pebs = ubi->good_peb_count - ubi->corr_peb_count; |
801c135c AB |
845 | |
846 | /* | |
847 | * The layout volume is OK, initialize the corresponding in-RAM data | |
848 | * structures. | |
849 | */ | |
850 | err = init_volumes(ubi, si, ubi->vtbl); | |
851 | if (err) | |
852 | goto out_free; | |
853 | ||
854 | /* | |
be436f62 | 855 | * Make sure that the scanning information is consistent to the |
801c135c AB |
856 | * information stored in the volume table. |
857 | */ | |
858 | err = check_scanning_info(ubi, si); | |
859 | if (err) | |
860 | goto out_free; | |
861 | ||
862 | return 0; | |
863 | ||
864 | out_free: | |
92ad8f37 | 865 | vfree(ubi->vtbl); |
9c9ec147 AB |
866 | for (i = 0; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) { |
867 | kfree(ubi->volumes[i]); | |
868 | ubi->volumes[i] = NULL; | |
869 | } | |
801c135c AB |
870 | return err; |
871 | } | |
872 | ||
92d124f5 | 873 | #ifdef CONFIG_MTD_UBI_DEBUG |
801c135c AB |
874 | |
875 | /** | |
876 | * paranoid_vtbl_check - check volume table. | |
877 | * @ubi: UBI device description object | |
878 | */ | |
879 | static void paranoid_vtbl_check(const struct ubi_device *ubi) | |
880 | { | |
92d124f5 AB |
881 | if (!(ubi_chk_flags & UBI_CHK_GEN)) |
882 | return; | |
883 | ||
801c135c AB |
884 | if (vtbl_check(ubi, ubi->vtbl)) { |
885 | ubi_err("paranoid check failed"); | |
886 | BUG(); | |
887 | } | |
888 | } | |
889 | ||
92d124f5 | 890 | #endif /* CONFIG_MTD_UBI_DEBUG */ |