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 | |
fbd0107f | 40 | * information about how much data static volumes contain. |
801c135c AB |
41 | * |
42 | * But it would still be beneficial to store this information in the volume | |
43 | * table. For example, suppose we have a static volume X, and all its physical | |
44 | * eraseblocks became bad for some reasons. Suppose we are attaching the | |
fbd0107f | 45 | * corresponding MTD device, for some reason we find no logical eraseblocks |
801c135c AB |
46 | * corresponding to the volume X. According to the volume table volume X does |
47 | * exist. So we don't know whether it is just empty or all its physical | |
fbd0107f | 48 | * eraseblocks went bad. So we cannot alarm the user properly. |
801c135c AB |
49 | * |
50 | * The volume table also stores so-called "update marker", which is used for | |
51 | * volume updates. Before updating the volume, the update marker is set, and | |
52 | * after the update operation is finished, the update marker is cleared. So if | |
53 | * the update operation was interrupted (e.g. by an unclean reboot) - the | |
54 | * update marker is still there and we know that the volume's contents is | |
55 | * damaged. | |
56 | */ | |
57 | ||
58 | #include <linux/crc32.h> | |
59 | #include <linux/err.h> | |
5a0e3ad6 | 60 | #include <linux/slab.h> |
801c135c AB |
61 | #include <asm/div64.h> |
62 | #include "ubi.h" | |
63 | ||
7bf523ae | 64 | static void self_vtbl_check(const struct ubi_device *ubi); |
801c135c AB |
65 | |
66 | /* Empty volume table record */ | |
67 | static struct ubi_vtbl_record empty_vtbl_record; | |
68 | ||
69 | /** | |
70 | * ubi_change_vtbl_record - change volume table record. | |
71 | * @ubi: UBI device description object | |
72 | * @idx: table index to change | |
73 | * @vtbl_rec: new volume table record | |
74 | * | |
75 | * This function changes volume table record @idx. If @vtbl_rec is %NULL, empty | |
76 | * volume table record is written. The caller does not have to calculate CRC of | |
77 | * the record as it is done by this function. Returns zero in case of success | |
78 | * and a negative error code in case of failure. | |
79 | */ | |
80 | int ubi_change_vtbl_record(struct ubi_device *ubi, int idx, | |
81 | struct ubi_vtbl_record *vtbl_rec) | |
82 | { | |
83 | int i, err; | |
84 | uint32_t crc; | |
89b96b69 | 85 | struct ubi_volume *layout_vol; |
801c135c AB |
86 | |
87 | ubi_assert(idx >= 0 && idx < ubi->vtbl_slots); | |
91f2d53c | 88 | layout_vol = ubi->volumes[vol_id2idx(ubi, UBI_LAYOUT_VOLUME_ID)]; |
801c135c AB |
89 | |
90 | if (!vtbl_rec) | |
91 | vtbl_rec = &empty_vtbl_record; | |
92 | else { | |
93 | crc = crc32(UBI_CRC32_INIT, vtbl_rec, UBI_VTBL_RECORD_SIZE_CRC); | |
3261ebd7 | 94 | vtbl_rec->crc = cpu_to_be32(crc); |
801c135c AB |
95 | } |
96 | ||
801c135c AB |
97 | memcpy(&ubi->vtbl[idx], vtbl_rec, sizeof(struct ubi_vtbl_record)); |
98 | for (i = 0; i < UBI_LAYOUT_VOLUME_EBS; i++) { | |
89b96b69 | 99 | err = ubi_eba_unmap_leb(ubi, layout_vol, i); |
cae0a771 | 100 | if (err) |
801c135c | 101 | return err; |
cae0a771 | 102 | |
89b96b69 | 103 | err = ubi_eba_write_leb(ubi, layout_vol, i, ubi->vtbl, 0, |
b36a261e | 104 | ubi->vtbl_size); |
cae0a771 | 105 | if (err) |
801c135c | 106 | return err; |
801c135c AB |
107 | } |
108 | ||
7bf523ae | 109 | self_vtbl_check(ubi); |
6dc4a871 | 110 | return 0; |
801c135c AB |
111 | } |
112 | ||
f40ac9cd AB |
113 | /** |
114 | * ubi_vtbl_rename_volumes - rename UBI volumes in the volume table. | |
115 | * @ubi: UBI device description object | |
ebaaf1af | 116 | * @rename_list: list of &struct ubi_rename_entry objects |
f40ac9cd AB |
117 | * |
118 | * This function re-names multiple volumes specified in @req in the volume | |
119 | * table. Returns zero in case of success and a negative error code in case of | |
120 | * failure. | |
121 | */ | |
122 | int ubi_vtbl_rename_volumes(struct ubi_device *ubi, | |
123 | struct list_head *rename_list) | |
124 | { | |
125 | int i, err; | |
126 | struct ubi_rename_entry *re; | |
127 | struct ubi_volume *layout_vol; | |
128 | ||
129 | list_for_each_entry(re, rename_list, list) { | |
130 | uint32_t crc; | |
131 | struct ubi_volume *vol = re->desc->vol; | |
132 | struct ubi_vtbl_record *vtbl_rec = &ubi->vtbl[vol->vol_id]; | |
133 | ||
134 | if (re->remove) { | |
135 | memcpy(vtbl_rec, &empty_vtbl_record, | |
136 | sizeof(struct ubi_vtbl_record)); | |
137 | continue; | |
138 | } | |
139 | ||
140 | vtbl_rec->name_len = cpu_to_be16(re->new_name_len); | |
141 | memcpy(vtbl_rec->name, re->new_name, re->new_name_len); | |
142 | memset(vtbl_rec->name + re->new_name_len, 0, | |
143 | UBI_VOL_NAME_MAX + 1 - re->new_name_len); | |
144 | crc = crc32(UBI_CRC32_INIT, vtbl_rec, | |
145 | UBI_VTBL_RECORD_SIZE_CRC); | |
146 | vtbl_rec->crc = cpu_to_be32(crc); | |
147 | } | |
148 | ||
149 | layout_vol = ubi->volumes[vol_id2idx(ubi, UBI_LAYOUT_VOLUME_ID)]; | |
150 | for (i = 0; i < UBI_LAYOUT_VOLUME_EBS; i++) { | |
151 | err = ubi_eba_unmap_leb(ubi, layout_vol, i); | |
152 | if (err) | |
153 | return err; | |
154 | ||
155 | err = ubi_eba_write_leb(ubi, layout_vol, i, ubi->vtbl, 0, | |
b36a261e | 156 | ubi->vtbl_size); |
f40ac9cd AB |
157 | if (err) |
158 | return err; | |
159 | } | |
160 | ||
161 | return 0; | |
162 | } | |
163 | ||
801c135c | 164 | /** |
ebaaf1af | 165 | * vtbl_check - check if volume table is not corrupted and sensible. |
801c135c AB |
166 | * @ubi: UBI device description object |
167 | * @vtbl: volume table | |
168 | * | |
169 | * This function returns zero if @vtbl is all right, %1 if CRC is incorrect, | |
170 | * and %-EINVAL if it contains inconsistent data. | |
171 | */ | |
172 | static int vtbl_check(const struct ubi_device *ubi, | |
173 | const struct ubi_vtbl_record *vtbl) | |
174 | { | |
175 | int i, n, reserved_pebs, alignment, data_pad, vol_type, name_len; | |
979c9296 | 176 | int upd_marker, err; |
801c135c AB |
177 | uint32_t crc; |
178 | const char *name; | |
179 | ||
180 | for (i = 0; i < ubi->vtbl_slots; i++) { | |
181 | cond_resched(); | |
182 | ||
3261ebd7 CH |
183 | reserved_pebs = be32_to_cpu(vtbl[i].reserved_pebs); |
184 | alignment = be32_to_cpu(vtbl[i].alignment); | |
185 | data_pad = be32_to_cpu(vtbl[i].data_pad); | |
801c135c AB |
186 | upd_marker = vtbl[i].upd_marker; |
187 | vol_type = vtbl[i].vol_type; | |
3261ebd7 | 188 | name_len = be16_to_cpu(vtbl[i].name_len); |
801c135c AB |
189 | name = &vtbl[i].name[0]; |
190 | ||
191 | crc = crc32(UBI_CRC32_INIT, &vtbl[i], UBI_VTBL_RECORD_SIZE_CRC); | |
3261ebd7 | 192 | if (be32_to_cpu(vtbl[i].crc) != crc) { |
801c135c | 193 | ubi_err("bad CRC at record %u: %#08x, not %#08x", |
3261ebd7 | 194 | i, crc, be32_to_cpu(vtbl[i].crc)); |
1f021e1d | 195 | ubi_dump_vtbl_record(&vtbl[i], i); |
801c135c AB |
196 | return 1; |
197 | } | |
198 | ||
199 | if (reserved_pebs == 0) { | |
200 | if (memcmp(&vtbl[i], &empty_vtbl_record, | |
201 | UBI_VTBL_RECORD_SIZE)) { | |
979c9296 | 202 | err = 2; |
801c135c AB |
203 | goto bad; |
204 | } | |
205 | continue; | |
206 | } | |
207 | ||
208 | if (reserved_pebs < 0 || alignment < 0 || data_pad < 0 || | |
209 | name_len < 0) { | |
979c9296 | 210 | err = 3; |
801c135c AB |
211 | goto bad; |
212 | } | |
213 | ||
214 | if (alignment > ubi->leb_size || alignment == 0) { | |
979c9296 | 215 | err = 4; |
801c135c AB |
216 | goto bad; |
217 | } | |
218 | ||
cadb40cc | 219 | n = alignment & (ubi->min_io_size - 1); |
801c135c | 220 | if (alignment != 1 && n) { |
979c9296 | 221 | err = 5; |
801c135c AB |
222 | goto bad; |
223 | } | |
224 | ||
225 | n = ubi->leb_size % alignment; | |
226 | if (data_pad != n) { | |
e2986827 | 227 | ubi_err("bad data_pad, has to be %d", n); |
979c9296 | 228 | err = 6; |
801c135c AB |
229 | goto bad; |
230 | } | |
231 | ||
232 | if (vol_type != UBI_VID_DYNAMIC && vol_type != UBI_VID_STATIC) { | |
979c9296 | 233 | err = 7; |
801c135c AB |
234 | goto bad; |
235 | } | |
236 | ||
237 | if (upd_marker != 0 && upd_marker != 1) { | |
979c9296 | 238 | err = 8; |
801c135c AB |
239 | goto bad; |
240 | } | |
241 | ||
242 | if (reserved_pebs > ubi->good_peb_count) { | |
e2986827 | 243 | ubi_err("too large reserved_pebs %d, good PEBs %d", |
762a9f29 | 244 | reserved_pebs, ubi->good_peb_count); |
979c9296 | 245 | err = 9; |
801c135c AB |
246 | goto bad; |
247 | } | |
248 | ||
249 | if (name_len > UBI_VOL_NAME_MAX) { | |
979c9296 | 250 | err = 10; |
801c135c AB |
251 | goto bad; |
252 | } | |
253 | ||
254 | if (name[0] == '\0') { | |
979c9296 | 255 | err = 11; |
801c135c AB |
256 | goto bad; |
257 | } | |
258 | ||
259 | if (name_len != strnlen(name, name_len + 1)) { | |
979c9296 | 260 | err = 12; |
801c135c AB |
261 | goto bad; |
262 | } | |
263 | } | |
264 | ||
265 | /* Checks that all names are unique */ | |
266 | for (i = 0; i < ubi->vtbl_slots - 1; i++) { | |
267 | for (n = i + 1; n < ubi->vtbl_slots; n++) { | |
3261ebd7 CH |
268 | int len1 = be16_to_cpu(vtbl[i].name_len); |
269 | int len2 = be16_to_cpu(vtbl[n].name_len); | |
801c135c AB |
270 | |
271 | if (len1 > 0 && len1 == len2 && | |
272 | !strncmp(vtbl[i].name, vtbl[n].name, len1)) { | |
273 | ubi_err("volumes %d and %d have the same name" | |
274 | " \"%s\"", i, n, vtbl[i].name); | |
1f021e1d AB |
275 | ubi_dump_vtbl_record(&vtbl[i], i); |
276 | ubi_dump_vtbl_record(&vtbl[n], n); | |
801c135c AB |
277 | return -EINVAL; |
278 | } | |
279 | } | |
280 | } | |
281 | ||
282 | return 0; | |
283 | ||
284 | bad: | |
979c9296 | 285 | ubi_err("volume table check failed: record %d, error %d", i, err); |
1f021e1d | 286 | ubi_dump_vtbl_record(&vtbl[i], i); |
801c135c AB |
287 | return -EINVAL; |
288 | } | |
289 | ||
290 | /** | |
291 | * create_vtbl - create a copy of volume table. | |
292 | * @ubi: UBI device description object | |
a4e6042f | 293 | * @ai: attaching information |
801c135c AB |
294 | * @copy: number of the volume table copy |
295 | * @vtbl: contents of the volume table | |
296 | * | |
297 | * This function returns zero in case of success and a negative error code in | |
298 | * case of failure. | |
299 | */ | |
a4e6042f | 300 | static int create_vtbl(struct ubi_device *ubi, struct ubi_attach_info *ai, |
801c135c AB |
301 | int copy, void *vtbl) |
302 | { | |
303 | int err, tries = 0; | |
6bdccffe | 304 | struct ubi_vid_hdr *vid_hdr; |
2c5ec5ce | 305 | struct ubi_ainf_peb *new_aeb; |
801c135c AB |
306 | |
307 | ubi_msg("create volume table (copy #%d)", copy + 1); | |
308 | ||
33818bbb | 309 | vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL); |
801c135c AB |
310 | if (!vid_hdr) |
311 | return -ENOMEM; | |
312 | ||
801c135c | 313 | retry: |
c87fbd7d | 314 | new_aeb = ubi_early_get_peb(ubi, ai); |
2c5ec5ce AB |
315 | if (IS_ERR(new_aeb)) { |
316 | err = PTR_ERR(new_aeb); | |
801c135c AB |
317 | goto out_free; |
318 | } | |
319 | ||
1f4f4347 | 320 | vid_hdr->vol_type = UBI_LAYOUT_VOLUME_TYPE; |
91f2d53c | 321 | vid_hdr->vol_id = cpu_to_be32(UBI_LAYOUT_VOLUME_ID); |
801c135c AB |
322 | vid_hdr->compat = UBI_LAYOUT_VOLUME_COMPAT; |
323 | vid_hdr->data_size = vid_hdr->used_ebs = | |
3261ebd7 CH |
324 | vid_hdr->data_pad = cpu_to_be32(0); |
325 | vid_hdr->lnum = cpu_to_be32(copy); | |
a4e6042f | 326 | vid_hdr->sqnum = cpu_to_be64(++ai->max_sqnum); |
801c135c AB |
327 | |
328 | /* The EC header is already there, write the VID header */ | |
2c5ec5ce | 329 | err = ubi_io_write_vid_hdr(ubi, new_aeb->pnum, vid_hdr); |
801c135c AB |
330 | if (err) |
331 | goto write_error; | |
332 | ||
333 | /* Write the layout volume contents */ | |
2c5ec5ce | 334 | err = ubi_io_write_data(ubi, vtbl, new_aeb->pnum, 0, ubi->vtbl_size); |
801c135c AB |
335 | if (err) |
336 | goto write_error; | |
337 | ||
338 | /* | |
a4e6042f | 339 | * And add it to the attaching information. Don't delete the old version |
3561188a | 340 | * of this LEB as it will be deleted and freed in 'ubi_add_to_av()'. |
801c135c | 341 | */ |
3561188a | 342 | err = ubi_add_to_av(ubi, ai, new_aeb->pnum, new_aeb->ec, vid_hdr, 0); |
78b495c3 | 343 | kmem_cache_free(ai->aeb_slab_cache, new_aeb); |
801c135c AB |
344 | ubi_free_vid_hdr(ubi, vid_hdr); |
345 | return err; | |
346 | ||
347 | write_error: | |
78d87c95 AB |
348 | if (err == -EIO && ++tries <= 5) { |
349 | /* | |
350 | * Probably this physical eraseblock went bad, try to pick | |
351 | * another one. | |
352 | */ | |
a4e6042f | 353 | list_add(&new_aeb->u.list, &ai->erase); |
c4e90ec0 | 354 | goto retry; |
78d87c95 | 355 | } |
78b495c3 | 356 | kmem_cache_free(ai->aeb_slab_cache, new_aeb); |
801c135c AB |
357 | out_free: |
358 | ubi_free_vid_hdr(ubi, vid_hdr); | |
359 | return err; | |
360 | ||
361 | } | |
362 | ||
363 | /** | |
364 | * process_lvol - process the layout volume. | |
365 | * @ubi: UBI device description object | |
a4e6042f | 366 | * @ai: attaching information |
517af48c | 367 | * @av: layout volume attaching information |
801c135c AB |
368 | * |
369 | * This function is responsible for reading the layout volume, ensuring it is | |
370 | * not corrupted, and recovering from corruptions if needed. Returns volume | |
371 | * table in case of success and a negative error code in case of failure. | |
372 | */ | |
e88d6e10 | 373 | static struct ubi_vtbl_record *process_lvol(struct ubi_device *ubi, |
a4e6042f | 374 | struct ubi_attach_info *ai, |
517af48c | 375 | struct ubi_ainf_volume *av) |
801c135c AB |
376 | { |
377 | int err; | |
378 | struct rb_node *rb; | |
2c5ec5ce | 379 | struct ubi_ainf_peb *aeb; |
801c135c AB |
380 | struct ubi_vtbl_record *leb[UBI_LAYOUT_VOLUME_EBS] = { NULL, NULL }; |
381 | int leb_corrupted[UBI_LAYOUT_VOLUME_EBS] = {1, 1}; | |
382 | ||
383 | /* | |
384 | * UBI goes through the following steps when it changes the layout | |
385 | * volume: | |
386 | * a. erase LEB 0; | |
387 | * b. write new data to LEB 0; | |
388 | * c. erase LEB 1; | |
389 | * d. write new data to LEB 1. | |
390 | * | |
391 | * Before the change, both LEBs contain the same data. | |
392 | * | |
393 | * Due to unclean reboots, the contents of LEB 0 may be lost, but there | |
394 | * should LEB 1. So it is OK if LEB 0 is corrupted while LEB 1 is not. | |
395 | * Similarly, LEB 1 may be lost, but there should be LEB 0. And | |
396 | * finally, unclean reboots may result in a situation when neither LEB | |
397 | * 0 nor LEB 1 are corrupted, but they are different. In this case, LEB | |
398 | * 0 contains more recent information. | |
399 | * | |
400 | * So the plan is to first check LEB 0. Then | |
be436f62 | 401 | * a. if LEB 0 is OK, it must be containing the most recent data; then |
801c135c AB |
402 | * we compare it with LEB 1, and if they are different, we copy LEB |
403 | * 0 to LEB 1; | |
404 | * b. if LEB 0 is corrupted, but LEB 1 has to be OK, and we copy LEB 1 | |
405 | * to LEB 0. | |
406 | */ | |
407 | ||
c8566350 | 408 | dbg_gen("check layout volume"); |
801c135c AB |
409 | |
410 | /* Read both LEB 0 and LEB 1 into memory */ | |
517af48c | 411 | ubi_rb_for_each_entry(rb, aeb, &av->root, u.rb) { |
2c5ec5ce AB |
412 | leb[aeb->lnum] = vzalloc(ubi->vtbl_size); |
413 | if (!leb[aeb->lnum]) { | |
801c135c AB |
414 | err = -ENOMEM; |
415 | goto out_free; | |
416 | } | |
417 | ||
2c5ec5ce | 418 | err = ubi_io_read_data(ubi, leb[aeb->lnum], aeb->pnum, 0, |
801c135c | 419 | ubi->vtbl_size); |
d57f4054 | 420 | if (err == UBI_IO_BITFLIPS || mtd_is_eccerr(err)) |
beeea636 AB |
421 | /* |
422 | * Scrub the PEB later. Note, -EBADMSG indicates an | |
423 | * uncorrectable ECC error, but we have our own CRC and | |
424 | * the data will be checked later. If the data is OK, | |
425 | * the PEB will be scrubbed (because we set | |
2c5ec5ce | 426 | * aeb->scrub). If the data is not OK, the contents of |
beeea636 | 427 | * the PEB will be recovered from the second copy, and |
2c5ec5ce | 428 | * aeb->scrub will be cleared in |
3561188a | 429 | * 'ubi_add_to_av()'. |
beeea636 | 430 | */ |
2c5ec5ce | 431 | aeb->scrub = 1; |
801c135c AB |
432 | else if (err) |
433 | goto out_free; | |
434 | } | |
435 | ||
436 | err = -EINVAL; | |
437 | if (leb[0]) { | |
438 | leb_corrupted[0] = vtbl_check(ubi, leb[0]); | |
439 | if (leb_corrupted[0] < 0) | |
440 | goto out_free; | |
441 | } | |
442 | ||
443 | if (!leb_corrupted[0]) { | |
444 | /* LEB 0 is OK */ | |
445 | if (leb[1]) | |
9c9ec147 AB |
446 | leb_corrupted[1] = memcmp(leb[0], leb[1], |
447 | ubi->vtbl_size); | |
801c135c AB |
448 | if (leb_corrupted[1]) { |
449 | ubi_warn("volume table copy #2 is corrupted"); | |
a4e6042f | 450 | err = create_vtbl(ubi, ai, 1, leb[0]); |
801c135c AB |
451 | if (err) |
452 | goto out_free; | |
453 | ubi_msg("volume table was restored"); | |
454 | } | |
455 | ||
456 | /* Both LEB 1 and LEB 2 are OK and consistent */ | |
92ad8f37 | 457 | vfree(leb[1]); |
801c135c AB |
458 | return leb[0]; |
459 | } else { | |
460 | /* LEB 0 is corrupted or does not exist */ | |
461 | if (leb[1]) { | |
462 | leb_corrupted[1] = vtbl_check(ubi, leb[1]); | |
463 | if (leb_corrupted[1] < 0) | |
464 | goto out_free; | |
465 | } | |
466 | if (leb_corrupted[1]) { | |
467 | /* Both LEB 0 and LEB 1 are corrupted */ | |
468 | ubi_err("both volume tables are corrupted"); | |
469 | goto out_free; | |
470 | } | |
471 | ||
472 | ubi_warn("volume table copy #1 is corrupted"); | |
a4e6042f | 473 | err = create_vtbl(ubi, ai, 0, leb[1]); |
801c135c AB |
474 | if (err) |
475 | goto out_free; | |
476 | ubi_msg("volume table was restored"); | |
477 | ||
92ad8f37 | 478 | vfree(leb[0]); |
801c135c AB |
479 | return leb[1]; |
480 | } | |
481 | ||
482 | out_free: | |
92ad8f37 AB |
483 | vfree(leb[0]); |
484 | vfree(leb[1]); | |
801c135c AB |
485 | return ERR_PTR(err); |
486 | } | |
487 | ||
488 | /** | |
489 | * create_empty_lvol - create empty layout volume. | |
490 | * @ubi: UBI device description object | |
a4e6042f | 491 | * @ai: attaching information |
801c135c AB |
492 | * |
493 | * This function returns volume table contents in case of success and a | |
494 | * negative error code in case of failure. | |
495 | */ | |
e88d6e10 | 496 | static struct ubi_vtbl_record *create_empty_lvol(struct ubi_device *ubi, |
a4e6042f | 497 | struct ubi_attach_info *ai) |
801c135c AB |
498 | { |
499 | int i; | |
500 | struct ubi_vtbl_record *vtbl; | |
501 | ||
309b5e4e | 502 | vtbl = vzalloc(ubi->vtbl_size); |
801c135c AB |
503 | if (!vtbl) |
504 | return ERR_PTR(-ENOMEM); | |
505 | ||
506 | for (i = 0; i < ubi->vtbl_slots; i++) | |
507 | memcpy(&vtbl[i], &empty_vtbl_record, UBI_VTBL_RECORD_SIZE); | |
508 | ||
509 | for (i = 0; i < UBI_LAYOUT_VOLUME_EBS; i++) { | |
510 | int err; | |
511 | ||
a4e6042f | 512 | err = create_vtbl(ubi, ai, i, vtbl); |
801c135c | 513 | if (err) { |
92ad8f37 | 514 | vfree(vtbl); |
801c135c AB |
515 | return ERR_PTR(err); |
516 | } | |
517 | } | |
518 | ||
519 | return vtbl; | |
520 | } | |
521 | ||
522 | /** | |
523 | * init_volumes - initialize volume information for existing volumes. | |
524 | * @ubi: UBI device description object | |
a4e6042f | 525 | * @ai: scanning information |
801c135c AB |
526 | * @vtbl: volume table |
527 | * | |
528 | * This function allocates volume description objects for existing volumes. | |
529 | * Returns zero in case of success and a negative error code in case of | |
530 | * failure. | |
531 | */ | |
afc15a81 | 532 | static int init_volumes(struct ubi_device *ubi, |
a4e6042f | 533 | const struct ubi_attach_info *ai, |
801c135c AB |
534 | const struct ubi_vtbl_record *vtbl) |
535 | { | |
536 | int i, reserved_pebs = 0; | |
517af48c | 537 | struct ubi_ainf_volume *av; |
801c135c AB |
538 | struct ubi_volume *vol; |
539 | ||
540 | for (i = 0; i < ubi->vtbl_slots; i++) { | |
541 | cond_resched(); | |
542 | ||
3261ebd7 | 543 | if (be32_to_cpu(vtbl[i].reserved_pebs) == 0) |
801c135c AB |
544 | continue; /* Empty record */ |
545 | ||
546 | vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL); | |
547 | if (!vol) | |
548 | return -ENOMEM; | |
549 | ||
3261ebd7 CH |
550 | vol->reserved_pebs = be32_to_cpu(vtbl[i].reserved_pebs); |
551 | vol->alignment = be32_to_cpu(vtbl[i].alignment); | |
552 | vol->data_pad = be32_to_cpu(vtbl[i].data_pad); | |
ff998793 | 553 | vol->upd_marker = vtbl[i].upd_marker; |
801c135c AB |
554 | vol->vol_type = vtbl[i].vol_type == UBI_VID_DYNAMIC ? |
555 | UBI_DYNAMIC_VOLUME : UBI_STATIC_VOLUME; | |
3261ebd7 | 556 | vol->name_len = be16_to_cpu(vtbl[i].name_len); |
801c135c AB |
557 | vol->usable_leb_size = ubi->leb_size - vol->data_pad; |
558 | memcpy(vol->name, vtbl[i].name, vol->name_len); | |
559 | vol->name[vol->name_len] = '\0'; | |
560 | vol->vol_id = i; | |
561 | ||
4ccf8cff AB |
562 | if (vtbl[i].flags & UBI_VTBL_AUTORESIZE_FLG) { |
563 | /* Auto re-size flag may be set only for one volume */ | |
564 | if (ubi->autoresize_vol_id != -1) { | |
025dfdaf | 565 | ubi_err("more than one auto-resize volume (%d " |
4ccf8cff | 566 | "and %d)", ubi->autoresize_vol_id, i); |
f7f02837 | 567 | kfree(vol); |
4ccf8cff AB |
568 | return -EINVAL; |
569 | } | |
570 | ||
571 | ubi->autoresize_vol_id = i; | |
572 | } | |
573 | ||
801c135c AB |
574 | ubi_assert(!ubi->volumes[i]); |
575 | ubi->volumes[i] = vol; | |
576 | ubi->vol_count += 1; | |
577 | vol->ubi = ubi; | |
578 | reserved_pebs += vol->reserved_pebs; | |
579 | ||
580 | /* | |
581 | * In case of dynamic volume UBI knows nothing about how many | |
582 | * data is stored there. So assume the whole volume is used. | |
583 | */ | |
584 | if (vol->vol_type == UBI_DYNAMIC_VOLUME) { | |
585 | vol->used_ebs = vol->reserved_pebs; | |
586 | vol->last_eb_bytes = vol->usable_leb_size; | |
d08c3b78 VA |
587 | vol->used_bytes = |
588 | (long long)vol->used_ebs * vol->usable_leb_size; | |
801c135c AB |
589 | continue; |
590 | } | |
591 | ||
592 | /* Static volumes only */ | |
dcd85fdd | 593 | av = ubi_find_av(ai, i); |
517af48c | 594 | if (!av) { |
801c135c AB |
595 | /* |
596 | * No eraseblocks belonging to this volume found. We | |
597 | * don't actually know whether this static volume is | |
598 | * completely corrupted or just contains no data. And | |
599 | * we cannot know this as long as data size is not | |
600 | * stored on flash. So we just assume the volume is | |
601 | * empty. FIXME: this should be handled. | |
602 | */ | |
603 | continue; | |
604 | } | |
605 | ||
517af48c | 606 | if (av->leb_count != av->used_ebs) { |
801c135c AB |
607 | /* |
608 | * We found a static volume which misses several | |
609 | * eraseblocks. Treat it as corrupted. | |
610 | */ | |
611 | ubi_warn("static volume %d misses %d LEBs - corrupted", | |
517af48c | 612 | av->vol_id, av->used_ebs - av->leb_count); |
801c135c AB |
613 | vol->corrupted = 1; |
614 | continue; | |
615 | } | |
616 | ||
517af48c | 617 | vol->used_ebs = av->used_ebs; |
d08c3b78 VA |
618 | vol->used_bytes = |
619 | (long long)(vol->used_ebs - 1) * vol->usable_leb_size; | |
517af48c AB |
620 | vol->used_bytes += av->last_data_size; |
621 | vol->last_eb_bytes = av->last_data_size; | |
801c135c AB |
622 | } |
623 | ||
d05c77a8 | 624 | /* And add the layout volume */ |
801c135c AB |
625 | vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL); |
626 | if (!vol) | |
627 | return -ENOMEM; | |
628 | ||
629 | vol->reserved_pebs = UBI_LAYOUT_VOLUME_EBS; | |
1f4f4347 | 630 | vol->alignment = UBI_LAYOUT_VOLUME_ALIGN; |
801c135c AB |
631 | vol->vol_type = UBI_DYNAMIC_VOLUME; |
632 | vol->name_len = sizeof(UBI_LAYOUT_VOLUME_NAME) - 1; | |
633 | memcpy(vol->name, UBI_LAYOUT_VOLUME_NAME, vol->name_len + 1); | |
634 | vol->usable_leb_size = ubi->leb_size; | |
635 | vol->used_ebs = vol->reserved_pebs; | |
636 | vol->last_eb_bytes = vol->reserved_pebs; | |
d08c3b78 VA |
637 | vol->used_bytes = |
638 | (long long)vol->used_ebs * (ubi->leb_size - vol->data_pad); | |
91f2d53c | 639 | vol->vol_id = UBI_LAYOUT_VOLUME_ID; |
d05c77a8 | 640 | vol->ref_count = 1; |
801c135c AB |
641 | |
642 | ubi_assert(!ubi->volumes[i]); | |
643 | ubi->volumes[vol_id2idx(ubi, vol->vol_id)] = vol; | |
644 | reserved_pebs += vol->reserved_pebs; | |
645 | ubi->vol_count += 1; | |
646 | vol->ubi = ubi; | |
647 | ||
5fc01ab6 | 648 | if (reserved_pebs > ubi->avail_pebs) { |
801c135c AB |
649 | ubi_err("not enough PEBs, required %d, available %d", |
650 | reserved_pebs, ubi->avail_pebs); | |
5fc01ab6 AB |
651 | if (ubi->corr_peb_count) |
652 | ubi_err("%d PEBs are corrupted and not used", | |
653 | ubi->corr_peb_count); | |
654 | } | |
801c135c AB |
655 | ubi->rsvd_pebs += reserved_pebs; |
656 | ubi->avail_pebs -= reserved_pebs; | |
657 | ||
658 | return 0; | |
659 | } | |
660 | ||
661 | /** | |
517af48c | 662 | * check_av - check volume attaching information. |
801c135c | 663 | * @vol: UBI volume description object |
517af48c | 664 | * @av: volume attaching information |
801c135c | 665 | * |
a4e6042f | 666 | * This function returns zero if the volume attaching information is consistent |
801c135c AB |
667 | * to the data read from the volume tabla, and %-EINVAL if not. |
668 | */ | |
517af48c AB |
669 | static int check_av(const struct ubi_volume *vol, |
670 | const struct ubi_ainf_volume *av) | |
801c135c | 671 | { |
979c9296 AB |
672 | int err; |
673 | ||
517af48c | 674 | if (av->highest_lnum >= vol->reserved_pebs) { |
979c9296 | 675 | err = 1; |
801c135c AB |
676 | goto bad; |
677 | } | |
517af48c | 678 | if (av->leb_count > vol->reserved_pebs) { |
979c9296 | 679 | err = 2; |
801c135c AB |
680 | goto bad; |
681 | } | |
517af48c | 682 | if (av->vol_type != vol->vol_type) { |
979c9296 | 683 | err = 3; |
801c135c AB |
684 | goto bad; |
685 | } | |
517af48c | 686 | if (av->used_ebs > vol->reserved_pebs) { |
979c9296 | 687 | err = 4; |
801c135c AB |
688 | goto bad; |
689 | } | |
517af48c | 690 | if (av->data_pad != vol->data_pad) { |
979c9296 | 691 | err = 5; |
801c135c AB |
692 | goto bad; |
693 | } | |
694 | return 0; | |
695 | ||
696 | bad: | |
a4e6042f | 697 | ubi_err("bad attaching information, error %d", err); |
517af48c | 698 | ubi_dump_av(av); |
766381f0 | 699 | ubi_dump_vol_info(vol); |
801c135c AB |
700 | return -EINVAL; |
701 | } | |
702 | ||
703 | /** | |
fbd0107f | 704 | * check_attaching_info - check that attaching information. |
801c135c | 705 | * @ubi: UBI device description object |
a4e6042f | 706 | * @ai: attaching information |
801c135c AB |
707 | * |
708 | * Even though we protect on-flash data by CRC checksums, we still don't trust | |
a4e6042f | 709 | * the media. This function ensures that attaching information is consistent to |
fbd0107f | 710 | * the information read from the volume table. Returns zero if the attaching |
801c135c AB |
711 | * information is OK and %-EINVAL if it is not. |
712 | */ | |
fbd0107f | 713 | static int check_attaching_info(const struct ubi_device *ubi, |
a4e6042f | 714 | struct ubi_attach_info *ai) |
801c135c AB |
715 | { |
716 | int err, i; | |
517af48c | 717 | struct ubi_ainf_volume *av; |
801c135c AB |
718 | struct ubi_volume *vol; |
719 | ||
a4e6042f | 720 | if (ai->vols_found > UBI_INT_VOL_COUNT + ubi->vtbl_slots) { |
fbd0107f | 721 | ubi_err("found %d volumes while attaching, maximum is %d + %d", |
a4e6042f | 722 | ai->vols_found, UBI_INT_VOL_COUNT, ubi->vtbl_slots); |
801c135c AB |
723 | return -EINVAL; |
724 | } | |
725 | ||
a4e6042f AB |
726 | if (ai->highest_vol_id >= ubi->vtbl_slots + UBI_INT_VOL_COUNT && |
727 | ai->highest_vol_id < UBI_INTERNAL_VOL_START) { | |
fbd0107f | 728 | ubi_err("too large volume ID %d found", ai->highest_vol_id); |
801c135c AB |
729 | return -EINVAL; |
730 | } | |
731 | ||
801c135c AB |
732 | for (i = 0; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) { |
733 | cond_resched(); | |
734 | ||
dcd85fdd | 735 | av = ubi_find_av(ai, i); |
801c135c AB |
736 | vol = ubi->volumes[i]; |
737 | if (!vol) { | |
517af48c | 738 | if (av) |
d717dc2f | 739 | ubi_remove_av(ai, av); |
801c135c AB |
740 | continue; |
741 | } | |
742 | ||
743 | if (vol->reserved_pebs == 0) { | |
744 | ubi_assert(i < ubi->vtbl_slots); | |
745 | ||
517af48c | 746 | if (!av) |
801c135c AB |
747 | continue; |
748 | ||
749 | /* | |
fbd0107f | 750 | * During attaching we found a volume which does not |
801c135c AB |
751 | * exist according to the information in the volume |
752 | * table. This must have happened due to an unclean | |
753 | * reboot while the volume was being removed. Discard | |
754 | * these eraseblocks. | |
755 | */ | |
517af48c | 756 | ubi_msg("finish volume %d removal", av->vol_id); |
d717dc2f | 757 | ubi_remove_av(ai, av); |
517af48c AB |
758 | } else if (av) { |
759 | err = check_av(vol, av); | |
801c135c AB |
760 | if (err) |
761 | return err; | |
762 | } | |
763 | } | |
764 | ||
765 | return 0; | |
766 | } | |
767 | ||
768 | /** | |
ebaaf1af | 769 | * ubi_read_volume_table - read the volume table. |
801c135c | 770 | * @ubi: UBI device description object |
a4e6042f | 771 | * @ai: attaching information |
801c135c AB |
772 | * |
773 | * This function reads volume table, checks it, recover from errors if needed, | |
774 | * or creates it if needed. Returns zero in case of success and a negative | |
775 | * error code in case of failure. | |
776 | */ | |
a4e6042f | 777 | int ubi_read_volume_table(struct ubi_device *ubi, struct ubi_attach_info *ai) |
801c135c AB |
778 | { |
779 | int i, err; | |
517af48c | 780 | struct ubi_ainf_volume *av; |
801c135c | 781 | |
3261ebd7 | 782 | empty_vtbl_record.crc = cpu_to_be32(0xf116c36b); |
801c135c AB |
783 | |
784 | /* | |
785 | * The number of supported volumes is limited by the eraseblock size | |
786 | * and by the UBI_MAX_VOLUMES constant. | |
787 | */ | |
788 | ubi->vtbl_slots = ubi->leb_size / UBI_VTBL_RECORD_SIZE; | |
789 | if (ubi->vtbl_slots > UBI_MAX_VOLUMES) | |
790 | ubi->vtbl_slots = UBI_MAX_VOLUMES; | |
791 | ||
792 | ubi->vtbl_size = ubi->vtbl_slots * UBI_VTBL_RECORD_SIZE; | |
793 | ubi->vtbl_size = ALIGN(ubi->vtbl_size, ubi->min_io_size); | |
794 | ||
dcd85fdd | 795 | av = ubi_find_av(ai, UBI_LAYOUT_VOLUME_ID); |
517af48c | 796 | if (!av) { |
801c135c AB |
797 | /* |
798 | * No logical eraseblocks belonging to the layout volume were | |
799 | * found. This could mean that the flash is just empty. In | |
800 | * this case we create empty layout volume. | |
801 | * | |
802 | * But if flash is not empty this must be a corruption or the | |
803 | * MTD device just contains garbage. | |
804 | */ | |
a4e6042f AB |
805 | if (ai->is_empty) { |
806 | ubi->vtbl = create_empty_lvol(ubi, ai); | |
801c135c AB |
807 | if (IS_ERR(ubi->vtbl)) |
808 | return PTR_ERR(ubi->vtbl); | |
809 | } else { | |
810 | ubi_err("the layout volume was not found"); | |
811 | return -EINVAL; | |
812 | } | |
813 | } else { | |
517af48c | 814 | if (av->leb_count > UBI_LAYOUT_VOLUME_EBS) { |
801c135c | 815 | /* This must not happen with proper UBI images */ |
e2986827 | 816 | ubi_err("too many LEBs (%d) in layout volume", |
517af48c | 817 | av->leb_count); |
801c135c AB |
818 | return -EINVAL; |
819 | } | |
820 | ||
517af48c | 821 | ubi->vtbl = process_lvol(ubi, ai, av); |
801c135c AB |
822 | if (IS_ERR(ubi->vtbl)) |
823 | return PTR_ERR(ubi->vtbl); | |
824 | } | |
825 | ||
5fc01ab6 | 826 | ubi->avail_pebs = ubi->good_peb_count - ubi->corr_peb_count; |
801c135c AB |
827 | |
828 | /* | |
829 | * The layout volume is OK, initialize the corresponding in-RAM data | |
830 | * structures. | |
831 | */ | |
a4e6042f | 832 | err = init_volumes(ubi, ai, ubi->vtbl); |
801c135c AB |
833 | if (err) |
834 | goto out_free; | |
835 | ||
836 | /* | |
a4e6042f | 837 | * Make sure that the attaching information is consistent to the |
801c135c AB |
838 | * information stored in the volume table. |
839 | */ | |
fbd0107f | 840 | err = check_attaching_info(ubi, ai); |
801c135c AB |
841 | if (err) |
842 | goto out_free; | |
843 | ||
844 | return 0; | |
845 | ||
846 | out_free: | |
92ad8f37 | 847 | vfree(ubi->vtbl); |
9c9ec147 AB |
848 | for (i = 0; i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) { |
849 | kfree(ubi->volumes[i]); | |
850 | ubi->volumes[i] = NULL; | |
851 | } | |
801c135c AB |
852 | return err; |
853 | } | |
854 | ||
801c135c | 855 | /** |
7bf523ae | 856 | * self_vtbl_check - check volume table. |
801c135c AB |
857 | * @ubi: UBI device description object |
858 | */ | |
7bf523ae | 859 | static void self_vtbl_check(const struct ubi_device *ubi) |
801c135c | 860 | { |
2a734bb8 | 861 | if (!ubi->dbg->chk_gen) |
92d124f5 AB |
862 | return; |
863 | ||
801c135c | 864 | if (vtbl_check(ubi, ubi->vtbl)) { |
7bf523ae | 865 | ubi_err("self-check failed"); |
801c135c AB |
866 | BUG(); |
867 | } | |
868 | } |