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