| 1 | /* |
| 2 | * Copyright (c) International Business Machines Corp., 2006 |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License as published by |
| 6 | * the Free Software Foundation; either version 2 of the License, or |
| 7 | * (at your option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
| 12 | * the GNU General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License |
| 15 | * along with this program; if not, write to the Free Software |
| 16 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 17 | * |
| 18 | * Author: Artem Bityutskiy (Битюцкий Артём) |
| 19 | */ |
| 20 | |
| 21 | /* |
| 22 | * UBI attaching sub-system. |
| 23 | * |
| 24 | * This sub-system is responsible for attaching MTD devices and it also |
| 25 | * implements flash media scanning. |
| 26 | * |
| 27 | * The attaching information is represented by a &struct ubi_attach_info' |
| 28 | * object. Information about volumes is represented by &struct ubi_ainf_volume |
| 29 | * objects which are kept in volume RB-tree with root at the @volumes field. |
| 30 | * The RB-tree is indexed by the volume ID. |
| 31 | * |
| 32 | * Logical eraseblocks are represented by &struct ubi_ainf_peb objects. These |
| 33 | * objects are kept in per-volume RB-trees with the root at the corresponding |
| 34 | * &struct ubi_ainf_volume object. To put it differently, we keep an RB-tree of |
| 35 | * per-volume objects and each of these objects is the root of RB-tree of |
| 36 | * per-LEB objects. |
| 37 | * |
| 38 | * Corrupted physical eraseblocks are put to the @corr list, free physical |
| 39 | * eraseblocks are put to the @free list and the physical eraseblock to be |
| 40 | * erased are put to the @erase list. |
| 41 | * |
| 42 | * About corruptions |
| 43 | * ~~~~~~~~~~~~~~~~~ |
| 44 | * |
| 45 | * UBI protects EC and VID headers with CRC-32 checksums, so it can detect |
| 46 | * whether the headers are corrupted or not. Sometimes UBI also protects the |
| 47 | * data with CRC-32, e.g., when it executes the atomic LEB change operation, or |
| 48 | * when it moves the contents of a PEB for wear-leveling purposes. |
| 49 | * |
| 50 | * UBI tries to distinguish between 2 types of corruptions. |
| 51 | * |
| 52 | * 1. Corruptions caused by power cuts. These are expected corruptions and UBI |
| 53 | * tries to handle them gracefully, without printing too many warnings and |
| 54 | * error messages. The idea is that we do not lose important data in these |
| 55 | * cases - we may lose only the data which were being written to the media just |
| 56 | * before the power cut happened, and the upper layers (e.g., UBIFS) are |
| 57 | * supposed to handle such data losses (e.g., by using the FS journal). |
| 58 | * |
| 59 | * When UBI detects a corruption (CRC-32 mismatch) in a PEB, and it looks like |
| 60 | * the reason is a power cut, UBI puts this PEB to the @erase list, and all |
| 61 | * PEBs in the @erase list are scheduled for erasure later. |
| 62 | * |
| 63 | * 2. Unexpected corruptions which are not caused by power cuts. During |
| 64 | * attaching, such PEBs are put to the @corr list and UBI preserves them. |
| 65 | * Obviously, this lessens the amount of available PEBs, and if at some point |
| 66 | * UBI runs out of free PEBs, it switches to R/O mode. UBI also loudly informs |
| 67 | * about such PEBs every time the MTD device is attached. |
| 68 | * |
| 69 | * However, it is difficult to reliably distinguish between these types of |
| 70 | * corruptions and UBI's strategy is as follows (in case of attaching by |
| 71 | * scanning). UBI assumes corruption type 2 if the VID header is corrupted and |
| 72 | * the data area does not contain all 0xFFs, and there were no bit-flips or |
| 73 | * integrity errors (e.g., ECC errors in case of NAND) while reading the data |
| 74 | * area. Otherwise UBI assumes corruption type 1. So the decision criteria |
| 75 | * are as follows. |
| 76 | * o If the data area contains only 0xFFs, there are no data, and it is safe |
| 77 | * to just erase this PEB - this is corruption type 1. |
| 78 | * o If the data area has bit-flips or data integrity errors (ECC errors on |
| 79 | * NAND), it is probably a PEB which was being erased when power cut |
| 80 | * happened, so this is corruption type 1. However, this is just a guess, |
| 81 | * which might be wrong. |
| 82 | * o Otherwise this is corruption type 2. |
| 83 | */ |
| 84 | |
| 85 | #include <linux/err.h> |
| 86 | #include <linux/slab.h> |
| 87 | #include <linux/crc32.h> |
| 88 | #include <linux/math64.h> |
| 89 | #include <linux/random.h> |
| 90 | #include "ubi.h" |
| 91 | |
| 92 | static int self_check_ai(struct ubi_device *ubi, struct ubi_attach_info *ai); |
| 93 | |
| 94 | /* Temporary variables used during scanning */ |
| 95 | static struct ubi_ec_hdr *ech; |
| 96 | static struct ubi_vid_hdr *vidh; |
| 97 | |
| 98 | /** |
| 99 | * add_to_list - add physical eraseblock to a list. |
| 100 | * @ai: attaching information |
| 101 | * @pnum: physical eraseblock number to add |
| 102 | * @vol_id: the last used volume id for the PEB |
| 103 | * @lnum: the last used LEB number for the PEB |
| 104 | * @ec: erase counter of the physical eraseblock |
| 105 | * @to_head: if not zero, add to the head of the list |
| 106 | * @list: the list to add to |
| 107 | * |
| 108 | * This function allocates a 'struct ubi_ainf_peb' object for physical |
| 109 | * eraseblock @pnum and adds it to the "free", "erase", or "alien" lists. |
| 110 | * It stores the @lnum and @vol_id alongside, which can both be |
| 111 | * %UBI_UNKNOWN if they are not available, not readable, or not assigned. |
| 112 | * If @to_head is not zero, PEB will be added to the head of the list, which |
| 113 | * basically means it will be processed first later. E.g., we add corrupted |
| 114 | * PEBs (corrupted due to power cuts) to the head of the erase list to make |
| 115 | * sure we erase them first and get rid of corruptions ASAP. This function |
| 116 | * returns zero in case of success and a negative error code in case of |
| 117 | * failure. |
| 118 | */ |
| 119 | static int add_to_list(struct ubi_attach_info *ai, int pnum, int vol_id, |
| 120 | int lnum, int ec, int to_head, struct list_head *list) |
| 121 | { |
| 122 | struct ubi_ainf_peb *aeb; |
| 123 | |
| 124 | if (list == &ai->free) { |
| 125 | dbg_bld("add to free: PEB %d, EC %d", pnum, ec); |
| 126 | } else if (list == &ai->erase) { |
| 127 | dbg_bld("add to erase: PEB %d, EC %d", pnum, ec); |
| 128 | } else if (list == &ai->alien) { |
| 129 | dbg_bld("add to alien: PEB %d, EC %d", pnum, ec); |
| 130 | ai->alien_peb_count += 1; |
| 131 | } else |
| 132 | BUG(); |
| 133 | |
| 134 | aeb = kmem_cache_alloc(ai->aeb_slab_cache, GFP_KERNEL); |
| 135 | if (!aeb) |
| 136 | return -ENOMEM; |
| 137 | |
| 138 | aeb->pnum = pnum; |
| 139 | aeb->vol_id = vol_id; |
| 140 | aeb->lnum = lnum; |
| 141 | aeb->ec = ec; |
| 142 | if (to_head) |
| 143 | list_add(&aeb->u.list, list); |
| 144 | else |
| 145 | list_add_tail(&aeb->u.list, list); |
| 146 | return 0; |
| 147 | } |
| 148 | |
| 149 | /** |
| 150 | * add_corrupted - add a corrupted physical eraseblock. |
| 151 | * @ai: attaching information |
| 152 | * @pnum: physical eraseblock number to add |
| 153 | * @ec: erase counter of the physical eraseblock |
| 154 | * |
| 155 | * This function allocates a 'struct ubi_ainf_peb' object for a corrupted |
| 156 | * physical eraseblock @pnum and adds it to the 'corr' list. The corruption |
| 157 | * was presumably not caused by a power cut. Returns zero in case of success |
| 158 | * and a negative error code in case of failure. |
| 159 | */ |
| 160 | static int add_corrupted(struct ubi_attach_info *ai, int pnum, int ec) |
| 161 | { |
| 162 | struct ubi_ainf_peb *aeb; |
| 163 | |
| 164 | dbg_bld("add to corrupted: PEB %d, EC %d", pnum, ec); |
| 165 | |
| 166 | aeb = kmem_cache_alloc(ai->aeb_slab_cache, GFP_KERNEL); |
| 167 | if (!aeb) |
| 168 | return -ENOMEM; |
| 169 | |
| 170 | ai->corr_peb_count += 1; |
| 171 | aeb->pnum = pnum; |
| 172 | aeb->ec = ec; |
| 173 | list_add(&aeb->u.list, &ai->corr); |
| 174 | return 0; |
| 175 | } |
| 176 | |
| 177 | /** |
| 178 | * add_fastmap - add a Fastmap related physical eraseblock. |
| 179 | * @ai: attaching information |
| 180 | * @pnum: physical eraseblock number the VID header came from |
| 181 | * @vid_hdr: the volume identifier header |
| 182 | * @ec: erase counter of the physical eraseblock |
| 183 | * |
| 184 | * This function allocates a 'struct ubi_ainf_peb' object for a Fastamp |
| 185 | * physical eraseblock @pnum and adds it to the 'fastmap' list. |
| 186 | * Such blocks can be Fastmap super and data blocks from both the most |
| 187 | * recent Fastmap we're attaching from or from old Fastmaps which will |
| 188 | * be erased. |
| 189 | */ |
| 190 | static int add_fastmap(struct ubi_attach_info *ai, int pnum, |
| 191 | struct ubi_vid_hdr *vid_hdr, int ec) |
| 192 | { |
| 193 | struct ubi_ainf_peb *aeb; |
| 194 | |
| 195 | aeb = kmem_cache_alloc(ai->aeb_slab_cache, GFP_KERNEL); |
| 196 | if (!aeb) |
| 197 | return -ENOMEM; |
| 198 | |
| 199 | aeb->pnum = pnum; |
| 200 | aeb->vol_id = be32_to_cpu(vidh->vol_id); |
| 201 | aeb->sqnum = be64_to_cpu(vidh->sqnum); |
| 202 | aeb->ec = ec; |
| 203 | list_add(&aeb->u.list, &ai->fastmap); |
| 204 | |
| 205 | dbg_bld("add to fastmap list: PEB %d, vol_id %d, sqnum: %llu", pnum, |
| 206 | aeb->vol_id, aeb->sqnum); |
| 207 | |
| 208 | return 0; |
| 209 | } |
| 210 | |
| 211 | /** |
| 212 | * validate_vid_hdr - check volume identifier header. |
| 213 | * @ubi: UBI device description object |
| 214 | * @vid_hdr: the volume identifier header to check |
| 215 | * @av: information about the volume this logical eraseblock belongs to |
| 216 | * @pnum: physical eraseblock number the VID header came from |
| 217 | * |
| 218 | * This function checks that data stored in @vid_hdr is consistent. Returns |
| 219 | * non-zero if an inconsistency was found and zero if not. |
| 220 | * |
| 221 | * Note, UBI does sanity check of everything it reads from the flash media. |
| 222 | * Most of the checks are done in the I/O sub-system. Here we check that the |
| 223 | * information in the VID header is consistent to the information in other VID |
| 224 | * headers of the same volume. |
| 225 | */ |
| 226 | static int validate_vid_hdr(const struct ubi_device *ubi, |
| 227 | const struct ubi_vid_hdr *vid_hdr, |
| 228 | const struct ubi_ainf_volume *av, int pnum) |
| 229 | { |
| 230 | int vol_type = vid_hdr->vol_type; |
| 231 | int vol_id = be32_to_cpu(vid_hdr->vol_id); |
| 232 | int used_ebs = be32_to_cpu(vid_hdr->used_ebs); |
| 233 | int data_pad = be32_to_cpu(vid_hdr->data_pad); |
| 234 | |
| 235 | if (av->leb_count != 0) { |
| 236 | int av_vol_type; |
| 237 | |
| 238 | /* |
| 239 | * This is not the first logical eraseblock belonging to this |
| 240 | * volume. Ensure that the data in its VID header is consistent |
| 241 | * to the data in previous logical eraseblock headers. |
| 242 | */ |
| 243 | |
| 244 | if (vol_id != av->vol_id) { |
| 245 | ubi_err(ubi, "inconsistent vol_id"); |
| 246 | goto bad; |
| 247 | } |
| 248 | |
| 249 | if (av->vol_type == UBI_STATIC_VOLUME) |
| 250 | av_vol_type = UBI_VID_STATIC; |
| 251 | else |
| 252 | av_vol_type = UBI_VID_DYNAMIC; |
| 253 | |
| 254 | if (vol_type != av_vol_type) { |
| 255 | ubi_err(ubi, "inconsistent vol_type"); |
| 256 | goto bad; |
| 257 | } |
| 258 | |
| 259 | if (used_ebs != av->used_ebs) { |
| 260 | ubi_err(ubi, "inconsistent used_ebs"); |
| 261 | goto bad; |
| 262 | } |
| 263 | |
| 264 | if (data_pad != av->data_pad) { |
| 265 | ubi_err(ubi, "inconsistent data_pad"); |
| 266 | goto bad; |
| 267 | } |
| 268 | } |
| 269 | |
| 270 | return 0; |
| 271 | |
| 272 | bad: |
| 273 | ubi_err(ubi, "inconsistent VID header at PEB %d", pnum); |
| 274 | ubi_dump_vid_hdr(vid_hdr); |
| 275 | ubi_dump_av(av); |
| 276 | return -EINVAL; |
| 277 | } |
| 278 | |
| 279 | /** |
| 280 | * add_volume - add volume to the attaching information. |
| 281 | * @ai: attaching information |
| 282 | * @vol_id: ID of the volume to add |
| 283 | * @pnum: physical eraseblock number |
| 284 | * @vid_hdr: volume identifier header |
| 285 | * |
| 286 | * If the volume corresponding to the @vid_hdr logical eraseblock is already |
| 287 | * present in the attaching information, this function does nothing. Otherwise |
| 288 | * it adds corresponding volume to the attaching information. Returns a pointer |
| 289 | * to the allocated "av" object in case of success and a negative error code in |
| 290 | * case of failure. |
| 291 | */ |
| 292 | static struct ubi_ainf_volume *add_volume(struct ubi_attach_info *ai, |
| 293 | int vol_id, int pnum, |
| 294 | const struct ubi_vid_hdr *vid_hdr) |
| 295 | { |
| 296 | struct ubi_ainf_volume *av; |
| 297 | struct rb_node **p = &ai->volumes.rb_node, *parent = NULL; |
| 298 | |
| 299 | ubi_assert(vol_id == be32_to_cpu(vid_hdr->vol_id)); |
| 300 | |
| 301 | /* Walk the volume RB-tree to look if this volume is already present */ |
| 302 | while (*p) { |
| 303 | parent = *p; |
| 304 | av = rb_entry(parent, struct ubi_ainf_volume, rb); |
| 305 | |
| 306 | if (vol_id == av->vol_id) |
| 307 | return av; |
| 308 | |
| 309 | if (vol_id > av->vol_id) |
| 310 | p = &(*p)->rb_left; |
| 311 | else |
| 312 | p = &(*p)->rb_right; |
| 313 | } |
| 314 | |
| 315 | /* The volume is absent - add it */ |
| 316 | av = kmalloc(sizeof(struct ubi_ainf_volume), GFP_KERNEL); |
| 317 | if (!av) |
| 318 | return ERR_PTR(-ENOMEM); |
| 319 | |
| 320 | av->highest_lnum = av->leb_count = 0; |
| 321 | av->vol_id = vol_id; |
| 322 | av->root = RB_ROOT; |
| 323 | av->used_ebs = be32_to_cpu(vid_hdr->used_ebs); |
| 324 | av->data_pad = be32_to_cpu(vid_hdr->data_pad); |
| 325 | av->compat = vid_hdr->compat; |
| 326 | av->vol_type = vid_hdr->vol_type == UBI_VID_DYNAMIC ? UBI_DYNAMIC_VOLUME |
| 327 | : UBI_STATIC_VOLUME; |
| 328 | if (vol_id > ai->highest_vol_id) |
| 329 | ai->highest_vol_id = vol_id; |
| 330 | |
| 331 | rb_link_node(&av->rb, parent, p); |
| 332 | rb_insert_color(&av->rb, &ai->volumes); |
| 333 | ai->vols_found += 1; |
| 334 | dbg_bld("added volume %d", vol_id); |
| 335 | return av; |
| 336 | } |
| 337 | |
| 338 | /** |
| 339 | * ubi_compare_lebs - find out which logical eraseblock is newer. |
| 340 | * @ubi: UBI device description object |
| 341 | * @aeb: first logical eraseblock to compare |
| 342 | * @pnum: physical eraseblock number of the second logical eraseblock to |
| 343 | * compare |
| 344 | * @vid_hdr: volume identifier header of the second logical eraseblock |
| 345 | * |
| 346 | * This function compares 2 copies of a LEB and informs which one is newer. In |
| 347 | * case of success this function returns a positive value, in case of failure, a |
| 348 | * negative error code is returned. The success return codes use the following |
| 349 | * bits: |
| 350 | * o bit 0 is cleared: the first PEB (described by @aeb) is newer than the |
| 351 | * second PEB (described by @pnum and @vid_hdr); |
| 352 | * o bit 0 is set: the second PEB is newer; |
| 353 | * o bit 1 is cleared: no bit-flips were detected in the newer LEB; |
| 354 | * o bit 1 is set: bit-flips were detected in the newer LEB; |
| 355 | * o bit 2 is cleared: the older LEB is not corrupted; |
| 356 | * o bit 2 is set: the older LEB is corrupted. |
| 357 | */ |
| 358 | int ubi_compare_lebs(struct ubi_device *ubi, const struct ubi_ainf_peb *aeb, |
| 359 | int pnum, const struct ubi_vid_hdr *vid_hdr) |
| 360 | { |
| 361 | int len, err, second_is_newer, bitflips = 0, corrupted = 0; |
| 362 | uint32_t data_crc, crc; |
| 363 | struct ubi_vid_hdr *vh = NULL; |
| 364 | unsigned long long sqnum2 = be64_to_cpu(vid_hdr->sqnum); |
| 365 | |
| 366 | if (sqnum2 == aeb->sqnum) { |
| 367 | /* |
| 368 | * This must be a really ancient UBI image which has been |
| 369 | * created before sequence numbers support has been added. At |
| 370 | * that times we used 32-bit LEB versions stored in logical |
| 371 | * eraseblocks. That was before UBI got into mainline. We do not |
| 372 | * support these images anymore. Well, those images still work, |
| 373 | * but only if no unclean reboots happened. |
| 374 | */ |
| 375 | ubi_err(ubi, "unsupported on-flash UBI format"); |
| 376 | return -EINVAL; |
| 377 | } |
| 378 | |
| 379 | /* Obviously the LEB with lower sequence counter is older */ |
| 380 | second_is_newer = (sqnum2 > aeb->sqnum); |
| 381 | |
| 382 | /* |
| 383 | * Now we know which copy is newer. If the copy flag of the PEB with |
| 384 | * newer version is not set, then we just return, otherwise we have to |
| 385 | * check data CRC. For the second PEB we already have the VID header, |
| 386 | * for the first one - we'll need to re-read it from flash. |
| 387 | * |
| 388 | * Note: this may be optimized so that we wouldn't read twice. |
| 389 | */ |
| 390 | |
| 391 | if (second_is_newer) { |
| 392 | if (!vid_hdr->copy_flag) { |
| 393 | /* It is not a copy, so it is newer */ |
| 394 | dbg_bld("second PEB %d is newer, copy_flag is unset", |
| 395 | pnum); |
| 396 | return 1; |
| 397 | } |
| 398 | } else { |
| 399 | if (!aeb->copy_flag) { |
| 400 | /* It is not a copy, so it is newer */ |
| 401 | dbg_bld("first PEB %d is newer, copy_flag is unset", |
| 402 | pnum); |
| 403 | return bitflips << 1; |
| 404 | } |
| 405 | |
| 406 | vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL); |
| 407 | if (!vh) |
| 408 | return -ENOMEM; |
| 409 | |
| 410 | pnum = aeb->pnum; |
| 411 | err = ubi_io_read_vid_hdr(ubi, pnum, vh, 0); |
| 412 | if (err) { |
| 413 | if (err == UBI_IO_BITFLIPS) |
| 414 | bitflips = 1; |
| 415 | else { |
| 416 | ubi_err(ubi, "VID of PEB %d header is bad, but it was OK earlier, err %d", |
| 417 | pnum, err); |
| 418 | if (err > 0) |
| 419 | err = -EIO; |
| 420 | |
| 421 | goto out_free_vidh; |
| 422 | } |
| 423 | } |
| 424 | |
| 425 | vid_hdr = vh; |
| 426 | } |
| 427 | |
| 428 | /* Read the data of the copy and check the CRC */ |
| 429 | |
| 430 | len = be32_to_cpu(vid_hdr->data_size); |
| 431 | |
| 432 | mutex_lock(&ubi->buf_mutex); |
| 433 | err = ubi_io_read_data(ubi, ubi->peb_buf, pnum, 0, len); |
| 434 | if (err && err != UBI_IO_BITFLIPS && !mtd_is_eccerr(err)) |
| 435 | goto out_unlock; |
| 436 | |
| 437 | data_crc = be32_to_cpu(vid_hdr->data_crc); |
| 438 | crc = crc32(UBI_CRC32_INIT, ubi->peb_buf, len); |
| 439 | if (crc != data_crc) { |
| 440 | dbg_bld("PEB %d CRC error: calculated %#08x, must be %#08x", |
| 441 | pnum, crc, data_crc); |
| 442 | corrupted = 1; |
| 443 | bitflips = 0; |
| 444 | second_is_newer = !second_is_newer; |
| 445 | } else { |
| 446 | dbg_bld("PEB %d CRC is OK", pnum); |
| 447 | bitflips |= !!err; |
| 448 | } |
| 449 | mutex_unlock(&ubi->buf_mutex); |
| 450 | |
| 451 | ubi_free_vid_hdr(ubi, vh); |
| 452 | |
| 453 | if (second_is_newer) |
| 454 | dbg_bld("second PEB %d is newer, copy_flag is set", pnum); |
| 455 | else |
| 456 | dbg_bld("first PEB %d is newer, copy_flag is set", pnum); |
| 457 | |
| 458 | return second_is_newer | (bitflips << 1) | (corrupted << 2); |
| 459 | |
| 460 | out_unlock: |
| 461 | mutex_unlock(&ubi->buf_mutex); |
| 462 | out_free_vidh: |
| 463 | ubi_free_vid_hdr(ubi, vh); |
| 464 | return err; |
| 465 | } |
| 466 | |
| 467 | /** |
| 468 | * ubi_add_to_av - add used physical eraseblock to the attaching information. |
| 469 | * @ubi: UBI device description object |
| 470 | * @ai: attaching information |
| 471 | * @pnum: the physical eraseblock number |
| 472 | * @ec: erase counter |
| 473 | * @vid_hdr: the volume identifier header |
| 474 | * @bitflips: if bit-flips were detected when this physical eraseblock was read |
| 475 | * |
| 476 | * This function adds information about a used physical eraseblock to the |
| 477 | * 'used' tree of the corresponding volume. The function is rather complex |
| 478 | * because it has to handle cases when this is not the first physical |
| 479 | * eraseblock belonging to the same logical eraseblock, and the newer one has |
| 480 | * to be picked, while the older one has to be dropped. This function returns |
| 481 | * zero in case of success and a negative error code in case of failure. |
| 482 | */ |
| 483 | int ubi_add_to_av(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum, |
| 484 | int ec, const struct ubi_vid_hdr *vid_hdr, int bitflips) |
| 485 | { |
| 486 | int err, vol_id, lnum; |
| 487 | unsigned long long sqnum; |
| 488 | struct ubi_ainf_volume *av; |
| 489 | struct ubi_ainf_peb *aeb; |
| 490 | struct rb_node **p, *parent = NULL; |
| 491 | |
| 492 | vol_id = be32_to_cpu(vid_hdr->vol_id); |
| 493 | lnum = be32_to_cpu(vid_hdr->lnum); |
| 494 | sqnum = be64_to_cpu(vid_hdr->sqnum); |
| 495 | |
| 496 | dbg_bld("PEB %d, LEB %d:%d, EC %d, sqnum %llu, bitflips %d", |
| 497 | pnum, vol_id, lnum, ec, sqnum, bitflips); |
| 498 | |
| 499 | av = add_volume(ai, vol_id, pnum, vid_hdr); |
| 500 | if (IS_ERR(av)) |
| 501 | return PTR_ERR(av); |
| 502 | |
| 503 | if (ai->max_sqnum < sqnum) |
| 504 | ai->max_sqnum = sqnum; |
| 505 | |
| 506 | /* |
| 507 | * Walk the RB-tree of logical eraseblocks of volume @vol_id to look |
| 508 | * if this is the first instance of this logical eraseblock or not. |
| 509 | */ |
| 510 | p = &av->root.rb_node; |
| 511 | while (*p) { |
| 512 | int cmp_res; |
| 513 | |
| 514 | parent = *p; |
| 515 | aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb); |
| 516 | if (lnum != aeb->lnum) { |
| 517 | if (lnum < aeb->lnum) |
| 518 | p = &(*p)->rb_left; |
| 519 | else |
| 520 | p = &(*p)->rb_right; |
| 521 | continue; |
| 522 | } |
| 523 | |
| 524 | /* |
| 525 | * There is already a physical eraseblock describing the same |
| 526 | * logical eraseblock present. |
| 527 | */ |
| 528 | |
| 529 | dbg_bld("this LEB already exists: PEB %d, sqnum %llu, EC %d", |
| 530 | aeb->pnum, aeb->sqnum, aeb->ec); |
| 531 | |
| 532 | /* |
| 533 | * Make sure that the logical eraseblocks have different |
| 534 | * sequence numbers. Otherwise the image is bad. |
| 535 | * |
| 536 | * However, if the sequence number is zero, we assume it must |
| 537 | * be an ancient UBI image from the era when UBI did not have |
| 538 | * sequence numbers. We still can attach these images, unless |
| 539 | * there is a need to distinguish between old and new |
| 540 | * eraseblocks, in which case we'll refuse the image in |
| 541 | * 'ubi_compare_lebs()'. In other words, we attach old clean |
| 542 | * images, but refuse attaching old images with duplicated |
| 543 | * logical eraseblocks because there was an unclean reboot. |
| 544 | */ |
| 545 | if (aeb->sqnum == sqnum && sqnum != 0) { |
| 546 | ubi_err(ubi, "two LEBs with same sequence number %llu", |
| 547 | sqnum); |
| 548 | ubi_dump_aeb(aeb, 0); |
| 549 | ubi_dump_vid_hdr(vid_hdr); |
| 550 | return -EINVAL; |
| 551 | } |
| 552 | |
| 553 | /* |
| 554 | * Now we have to drop the older one and preserve the newer |
| 555 | * one. |
| 556 | */ |
| 557 | cmp_res = ubi_compare_lebs(ubi, aeb, pnum, vid_hdr); |
| 558 | if (cmp_res < 0) |
| 559 | return cmp_res; |
| 560 | |
| 561 | if (cmp_res & 1) { |
| 562 | /* |
| 563 | * This logical eraseblock is newer than the one |
| 564 | * found earlier. |
| 565 | */ |
| 566 | err = validate_vid_hdr(ubi, vid_hdr, av, pnum); |
| 567 | if (err) |
| 568 | return err; |
| 569 | |
| 570 | err = add_to_list(ai, aeb->pnum, aeb->vol_id, |
| 571 | aeb->lnum, aeb->ec, cmp_res & 4, |
| 572 | &ai->erase); |
| 573 | if (err) |
| 574 | return err; |
| 575 | |
| 576 | aeb->ec = ec; |
| 577 | aeb->pnum = pnum; |
| 578 | aeb->vol_id = vol_id; |
| 579 | aeb->lnum = lnum; |
| 580 | aeb->scrub = ((cmp_res & 2) || bitflips); |
| 581 | aeb->copy_flag = vid_hdr->copy_flag; |
| 582 | aeb->sqnum = sqnum; |
| 583 | |
| 584 | if (av->highest_lnum == lnum) |
| 585 | av->last_data_size = |
| 586 | be32_to_cpu(vid_hdr->data_size); |
| 587 | |
| 588 | return 0; |
| 589 | } else { |
| 590 | /* |
| 591 | * This logical eraseblock is older than the one found |
| 592 | * previously. |
| 593 | */ |
| 594 | return add_to_list(ai, pnum, vol_id, lnum, ec, |
| 595 | cmp_res & 4, &ai->erase); |
| 596 | } |
| 597 | } |
| 598 | |
| 599 | /* |
| 600 | * We've met this logical eraseblock for the first time, add it to the |
| 601 | * attaching information. |
| 602 | */ |
| 603 | |
| 604 | err = validate_vid_hdr(ubi, vid_hdr, av, pnum); |
| 605 | if (err) |
| 606 | return err; |
| 607 | |
| 608 | aeb = kmem_cache_alloc(ai->aeb_slab_cache, GFP_KERNEL); |
| 609 | if (!aeb) |
| 610 | return -ENOMEM; |
| 611 | |
| 612 | aeb->ec = ec; |
| 613 | aeb->pnum = pnum; |
| 614 | aeb->vol_id = vol_id; |
| 615 | aeb->lnum = lnum; |
| 616 | aeb->scrub = bitflips; |
| 617 | aeb->copy_flag = vid_hdr->copy_flag; |
| 618 | aeb->sqnum = sqnum; |
| 619 | |
| 620 | if (av->highest_lnum <= lnum) { |
| 621 | av->highest_lnum = lnum; |
| 622 | av->last_data_size = be32_to_cpu(vid_hdr->data_size); |
| 623 | } |
| 624 | |
| 625 | av->leb_count += 1; |
| 626 | rb_link_node(&aeb->u.rb, parent, p); |
| 627 | rb_insert_color(&aeb->u.rb, &av->root); |
| 628 | return 0; |
| 629 | } |
| 630 | |
| 631 | /** |
| 632 | * ubi_find_av - find volume in the attaching information. |
| 633 | * @ai: attaching information |
| 634 | * @vol_id: the requested volume ID |
| 635 | * |
| 636 | * This function returns a pointer to the volume description or %NULL if there |
| 637 | * are no data about this volume in the attaching information. |
| 638 | */ |
| 639 | struct ubi_ainf_volume *ubi_find_av(const struct ubi_attach_info *ai, |
| 640 | int vol_id) |
| 641 | { |
| 642 | struct ubi_ainf_volume *av; |
| 643 | struct rb_node *p = ai->volumes.rb_node; |
| 644 | |
| 645 | while (p) { |
| 646 | av = rb_entry(p, struct ubi_ainf_volume, rb); |
| 647 | |
| 648 | if (vol_id == av->vol_id) |
| 649 | return av; |
| 650 | |
| 651 | if (vol_id > av->vol_id) |
| 652 | p = p->rb_left; |
| 653 | else |
| 654 | p = p->rb_right; |
| 655 | } |
| 656 | |
| 657 | return NULL; |
| 658 | } |
| 659 | |
| 660 | /** |
| 661 | * ubi_remove_av - delete attaching information about a volume. |
| 662 | * @ai: attaching information |
| 663 | * @av: the volume attaching information to delete |
| 664 | */ |
| 665 | void ubi_remove_av(struct ubi_attach_info *ai, struct ubi_ainf_volume *av) |
| 666 | { |
| 667 | struct rb_node *rb; |
| 668 | struct ubi_ainf_peb *aeb; |
| 669 | |
| 670 | dbg_bld("remove attaching information about volume %d", av->vol_id); |
| 671 | |
| 672 | while ((rb = rb_first(&av->root))) { |
| 673 | aeb = rb_entry(rb, struct ubi_ainf_peb, u.rb); |
| 674 | rb_erase(&aeb->u.rb, &av->root); |
| 675 | list_add_tail(&aeb->u.list, &ai->erase); |
| 676 | } |
| 677 | |
| 678 | rb_erase(&av->rb, &ai->volumes); |
| 679 | kfree(av); |
| 680 | ai->vols_found -= 1; |
| 681 | } |
| 682 | |
| 683 | /** |
| 684 | * early_erase_peb - erase a physical eraseblock. |
| 685 | * @ubi: UBI device description object |
| 686 | * @ai: attaching information |
| 687 | * @pnum: physical eraseblock number to erase; |
| 688 | * @ec: erase counter value to write (%UBI_UNKNOWN if it is unknown) |
| 689 | * |
| 690 | * This function erases physical eraseblock 'pnum', and writes the erase |
| 691 | * counter header to it. This function should only be used on UBI device |
| 692 | * initialization stages, when the EBA sub-system had not been yet initialized. |
| 693 | * This function returns zero in case of success and a negative error code in |
| 694 | * case of failure. |
| 695 | */ |
| 696 | static int early_erase_peb(struct ubi_device *ubi, |
| 697 | const struct ubi_attach_info *ai, int pnum, int ec) |
| 698 | { |
| 699 | int err; |
| 700 | struct ubi_ec_hdr *ec_hdr; |
| 701 | |
| 702 | if ((long long)ec >= UBI_MAX_ERASECOUNTER) { |
| 703 | /* |
| 704 | * Erase counter overflow. Upgrade UBI and use 64-bit |
| 705 | * erase counters internally. |
| 706 | */ |
| 707 | ubi_err(ubi, "erase counter overflow at PEB %d, EC %d", |
| 708 | pnum, ec); |
| 709 | return -EINVAL; |
| 710 | } |
| 711 | |
| 712 | ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL); |
| 713 | if (!ec_hdr) |
| 714 | return -ENOMEM; |
| 715 | |
| 716 | ec_hdr->ec = cpu_to_be64(ec); |
| 717 | |
| 718 | err = ubi_io_sync_erase(ubi, pnum, 0); |
| 719 | if (err < 0) |
| 720 | goto out_free; |
| 721 | |
| 722 | err = ubi_io_write_ec_hdr(ubi, pnum, ec_hdr); |
| 723 | |
| 724 | out_free: |
| 725 | kfree(ec_hdr); |
| 726 | return err; |
| 727 | } |
| 728 | |
| 729 | /** |
| 730 | * ubi_early_get_peb - get a free physical eraseblock. |
| 731 | * @ubi: UBI device description object |
| 732 | * @ai: attaching information |
| 733 | * |
| 734 | * This function returns a free physical eraseblock. It is supposed to be |
| 735 | * called on the UBI initialization stages when the wear-leveling sub-system is |
| 736 | * not initialized yet. This function picks a physical eraseblocks from one of |
| 737 | * the lists, writes the EC header if it is needed, and removes it from the |
| 738 | * list. |
| 739 | * |
| 740 | * This function returns a pointer to the "aeb" of the found free PEB in case |
| 741 | * of success and an error code in case of failure. |
| 742 | */ |
| 743 | struct ubi_ainf_peb *ubi_early_get_peb(struct ubi_device *ubi, |
| 744 | struct ubi_attach_info *ai) |
| 745 | { |
| 746 | int err = 0; |
| 747 | struct ubi_ainf_peb *aeb, *tmp_aeb; |
| 748 | |
| 749 | if (!list_empty(&ai->free)) { |
| 750 | aeb = list_entry(ai->free.next, struct ubi_ainf_peb, u.list); |
| 751 | list_del(&aeb->u.list); |
| 752 | dbg_bld("return free PEB %d, EC %d", aeb->pnum, aeb->ec); |
| 753 | return aeb; |
| 754 | } |
| 755 | |
| 756 | /* |
| 757 | * We try to erase the first physical eraseblock from the erase list |
| 758 | * and pick it if we succeed, or try to erase the next one if not. And |
| 759 | * so forth. We don't want to take care about bad eraseblocks here - |
| 760 | * they'll be handled later. |
| 761 | */ |
| 762 | list_for_each_entry_safe(aeb, tmp_aeb, &ai->erase, u.list) { |
| 763 | if (aeb->ec == UBI_UNKNOWN) |
| 764 | aeb->ec = ai->mean_ec; |
| 765 | |
| 766 | err = early_erase_peb(ubi, ai, aeb->pnum, aeb->ec+1); |
| 767 | if (err) |
| 768 | continue; |
| 769 | |
| 770 | aeb->ec += 1; |
| 771 | list_del(&aeb->u.list); |
| 772 | dbg_bld("return PEB %d, EC %d", aeb->pnum, aeb->ec); |
| 773 | return aeb; |
| 774 | } |
| 775 | |
| 776 | ubi_err(ubi, "no free eraseblocks"); |
| 777 | return ERR_PTR(-ENOSPC); |
| 778 | } |
| 779 | |
| 780 | /** |
| 781 | * check_corruption - check the data area of PEB. |
| 782 | * @ubi: UBI device description object |
| 783 | * @vid_hdr: the (corrupted) VID header of this PEB |
| 784 | * @pnum: the physical eraseblock number to check |
| 785 | * |
| 786 | * This is a helper function which is used to distinguish between VID header |
| 787 | * corruptions caused by power cuts and other reasons. If the PEB contains only |
| 788 | * 0xFF bytes in the data area, the VID header is most probably corrupted |
| 789 | * because of a power cut (%0 is returned in this case). Otherwise, it was |
| 790 | * probably corrupted for some other reasons (%1 is returned in this case). A |
| 791 | * negative error code is returned if a read error occurred. |
| 792 | * |
| 793 | * If the corruption reason was a power cut, UBI can safely erase this PEB. |
| 794 | * Otherwise, it should preserve it to avoid possibly destroying important |
| 795 | * information. |
| 796 | */ |
| 797 | static int check_corruption(struct ubi_device *ubi, struct ubi_vid_hdr *vid_hdr, |
| 798 | int pnum) |
| 799 | { |
| 800 | int err; |
| 801 | |
| 802 | mutex_lock(&ubi->buf_mutex); |
| 803 | memset(ubi->peb_buf, 0x00, ubi->leb_size); |
| 804 | |
| 805 | err = ubi_io_read(ubi, ubi->peb_buf, pnum, ubi->leb_start, |
| 806 | ubi->leb_size); |
| 807 | if (err == UBI_IO_BITFLIPS || mtd_is_eccerr(err)) { |
| 808 | /* |
| 809 | * Bit-flips or integrity errors while reading the data area. |
| 810 | * It is difficult to say for sure what type of corruption is |
| 811 | * this, but presumably a power cut happened while this PEB was |
| 812 | * erased, so it became unstable and corrupted, and should be |
| 813 | * erased. |
| 814 | */ |
| 815 | err = 0; |
| 816 | goto out_unlock; |
| 817 | } |
| 818 | |
| 819 | if (err) |
| 820 | goto out_unlock; |
| 821 | |
| 822 | if (ubi_check_pattern(ubi->peb_buf, 0xFF, ubi->leb_size)) |
| 823 | goto out_unlock; |
| 824 | |
| 825 | ubi_err(ubi, "PEB %d contains corrupted VID header, and the data does not contain all 0xFF", |
| 826 | pnum); |
| 827 | ubi_err(ubi, "this may be a non-UBI PEB or a severe VID header corruption which requires manual inspection"); |
| 828 | ubi_dump_vid_hdr(vid_hdr); |
| 829 | pr_err("hexdump of PEB %d offset %d, length %d", |
| 830 | pnum, ubi->leb_start, ubi->leb_size); |
| 831 | ubi_dbg_print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1, |
| 832 | ubi->peb_buf, ubi->leb_size, 1); |
| 833 | err = 1; |
| 834 | |
| 835 | out_unlock: |
| 836 | mutex_unlock(&ubi->buf_mutex); |
| 837 | return err; |
| 838 | } |
| 839 | |
| 840 | static bool vol_ignored(int vol_id) |
| 841 | { |
| 842 | switch (vol_id) { |
| 843 | case UBI_LAYOUT_VOLUME_ID: |
| 844 | return true; |
| 845 | } |
| 846 | |
| 847 | #ifdef CONFIG_MTD_UBI_FASTMAP |
| 848 | return ubi_is_fm_vol(vol_id); |
| 849 | #else |
| 850 | return false; |
| 851 | #endif |
| 852 | } |
| 853 | |
| 854 | /** |
| 855 | * scan_peb - scan and process UBI headers of a PEB. |
| 856 | * @ubi: UBI device description object |
| 857 | * @ai: attaching information |
| 858 | * @pnum: the physical eraseblock number |
| 859 | * @fast: true if we're scanning for a Fastmap |
| 860 | * |
| 861 | * This function reads UBI headers of PEB @pnum, checks them, and adds |
| 862 | * information about this PEB to the corresponding list or RB-tree in the |
| 863 | * "attaching info" structure. Returns zero if the physical eraseblock was |
| 864 | * successfully handled and a negative error code in case of failure. |
| 865 | */ |
| 866 | static int scan_peb(struct ubi_device *ubi, struct ubi_attach_info *ai, |
| 867 | int pnum, bool fast) |
| 868 | { |
| 869 | long long ec; |
| 870 | int err, bitflips = 0, vol_id = -1, ec_err = 0; |
| 871 | |
| 872 | dbg_bld("scan PEB %d", pnum); |
| 873 | |
| 874 | /* Skip bad physical eraseblocks */ |
| 875 | err = ubi_io_is_bad(ubi, pnum); |
| 876 | if (err < 0) |
| 877 | return err; |
| 878 | else if (err) { |
| 879 | ai->bad_peb_count += 1; |
| 880 | return 0; |
| 881 | } |
| 882 | |
| 883 | err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0); |
| 884 | if (err < 0) |
| 885 | return err; |
| 886 | switch (err) { |
| 887 | case 0: |
| 888 | break; |
| 889 | case UBI_IO_BITFLIPS: |
| 890 | bitflips = 1; |
| 891 | break; |
| 892 | case UBI_IO_FF: |
| 893 | ai->empty_peb_count += 1; |
| 894 | return add_to_list(ai, pnum, UBI_UNKNOWN, UBI_UNKNOWN, |
| 895 | UBI_UNKNOWN, 0, &ai->erase); |
| 896 | case UBI_IO_FF_BITFLIPS: |
| 897 | ai->empty_peb_count += 1; |
| 898 | return add_to_list(ai, pnum, UBI_UNKNOWN, UBI_UNKNOWN, |
| 899 | UBI_UNKNOWN, 1, &ai->erase); |
| 900 | case UBI_IO_BAD_HDR_EBADMSG: |
| 901 | case UBI_IO_BAD_HDR: |
| 902 | /* |
| 903 | * We have to also look at the VID header, possibly it is not |
| 904 | * corrupted. Set %bitflips flag in order to make this PEB be |
| 905 | * moved and EC be re-created. |
| 906 | */ |
| 907 | ec_err = err; |
| 908 | ec = UBI_UNKNOWN; |
| 909 | bitflips = 1; |
| 910 | break; |
| 911 | default: |
| 912 | ubi_err(ubi, "'ubi_io_read_ec_hdr()' returned unknown code %d", |
| 913 | err); |
| 914 | return -EINVAL; |
| 915 | } |
| 916 | |
| 917 | if (!ec_err) { |
| 918 | int image_seq; |
| 919 | |
| 920 | /* Make sure UBI version is OK */ |
| 921 | if (ech->version != UBI_VERSION) { |
| 922 | ubi_err(ubi, "this UBI version is %d, image version is %d", |
| 923 | UBI_VERSION, (int)ech->version); |
| 924 | return -EINVAL; |
| 925 | } |
| 926 | |
| 927 | ec = be64_to_cpu(ech->ec); |
| 928 | if (ec > UBI_MAX_ERASECOUNTER) { |
| 929 | /* |
| 930 | * Erase counter overflow. The EC headers have 64 bits |
| 931 | * reserved, but we anyway make use of only 31 bit |
| 932 | * values, as this seems to be enough for any existing |
| 933 | * flash. Upgrade UBI and use 64-bit erase counters |
| 934 | * internally. |
| 935 | */ |
| 936 | ubi_err(ubi, "erase counter overflow, max is %d", |
| 937 | UBI_MAX_ERASECOUNTER); |
| 938 | ubi_dump_ec_hdr(ech); |
| 939 | return -EINVAL; |
| 940 | } |
| 941 | |
| 942 | /* |
| 943 | * Make sure that all PEBs have the same image sequence number. |
| 944 | * This allows us to detect situations when users flash UBI |
| 945 | * images incorrectly, so that the flash has the new UBI image |
| 946 | * and leftovers from the old one. This feature was added |
| 947 | * relatively recently, and the sequence number was always |
| 948 | * zero, because old UBI implementations always set it to zero. |
| 949 | * For this reasons, we do not panic if some PEBs have zero |
| 950 | * sequence number, while other PEBs have non-zero sequence |
| 951 | * number. |
| 952 | */ |
| 953 | image_seq = be32_to_cpu(ech->image_seq); |
| 954 | if (!ubi->image_seq) |
| 955 | ubi->image_seq = image_seq; |
| 956 | if (image_seq && ubi->image_seq != image_seq) { |
| 957 | ubi_err(ubi, "bad image sequence number %d in PEB %d, expected %d", |
| 958 | image_seq, pnum, ubi->image_seq); |
| 959 | ubi_dump_ec_hdr(ech); |
| 960 | return -EINVAL; |
| 961 | } |
| 962 | } |
| 963 | |
| 964 | /* OK, we've done with the EC header, let's look at the VID header */ |
| 965 | |
| 966 | err = ubi_io_read_vid_hdr(ubi, pnum, vidh, 0); |
| 967 | if (err < 0) |
| 968 | return err; |
| 969 | switch (err) { |
| 970 | case 0: |
| 971 | break; |
| 972 | case UBI_IO_BITFLIPS: |
| 973 | bitflips = 1; |
| 974 | break; |
| 975 | case UBI_IO_BAD_HDR_EBADMSG: |
| 976 | if (ec_err == UBI_IO_BAD_HDR_EBADMSG) |
| 977 | /* |
| 978 | * Both EC and VID headers are corrupted and were read |
| 979 | * with data integrity error, probably this is a bad |
| 980 | * PEB, bit it is not marked as bad yet. This may also |
| 981 | * be a result of power cut during erasure. |
| 982 | */ |
| 983 | ai->maybe_bad_peb_count += 1; |
| 984 | case UBI_IO_BAD_HDR: |
| 985 | /* |
| 986 | * If we're facing a bad VID header we have to drop *all* |
| 987 | * Fastmap data structures we find. The most recent Fastmap |
| 988 | * could be bad and therefore there is a chance that we attach |
| 989 | * from an old one. On a fine MTD stack a PEB must not render |
| 990 | * bad all of a sudden, but the reality is different. |
| 991 | * So, let's be paranoid and help finding the root cause by |
| 992 | * falling back to scanning mode instead of attaching with a |
| 993 | * bad EBA table and cause data corruption which is hard to |
| 994 | * analyze. |
| 995 | */ |
| 996 | if (fast) |
| 997 | ai->force_full_scan = 1; |
| 998 | |
| 999 | if (ec_err) |
| 1000 | /* |
| 1001 | * Both headers are corrupted. There is a possibility |
| 1002 | * that this a valid UBI PEB which has corresponding |
| 1003 | * LEB, but the headers are corrupted. However, it is |
| 1004 | * impossible to distinguish it from a PEB which just |
| 1005 | * contains garbage because of a power cut during erase |
| 1006 | * operation. So we just schedule this PEB for erasure. |
| 1007 | * |
| 1008 | * Besides, in case of NOR flash, we deliberately |
| 1009 | * corrupt both headers because NOR flash erasure is |
| 1010 | * slow and can start from the end. |
| 1011 | */ |
| 1012 | err = 0; |
| 1013 | else |
| 1014 | /* |
| 1015 | * The EC was OK, but the VID header is corrupted. We |
| 1016 | * have to check what is in the data area. |
| 1017 | */ |
| 1018 | err = check_corruption(ubi, vidh, pnum); |
| 1019 | |
| 1020 | if (err < 0) |
| 1021 | return err; |
| 1022 | else if (!err) |
| 1023 | /* This corruption is caused by a power cut */ |
| 1024 | err = add_to_list(ai, pnum, UBI_UNKNOWN, |
| 1025 | UBI_UNKNOWN, ec, 1, &ai->erase); |
| 1026 | else |
| 1027 | /* This is an unexpected corruption */ |
| 1028 | err = add_corrupted(ai, pnum, ec); |
| 1029 | if (err) |
| 1030 | return err; |
| 1031 | goto adjust_mean_ec; |
| 1032 | case UBI_IO_FF_BITFLIPS: |
| 1033 | err = add_to_list(ai, pnum, UBI_UNKNOWN, UBI_UNKNOWN, |
| 1034 | ec, 1, &ai->erase); |
| 1035 | if (err) |
| 1036 | return err; |
| 1037 | goto adjust_mean_ec; |
| 1038 | case UBI_IO_FF: |
| 1039 | if (ec_err || bitflips) |
| 1040 | err = add_to_list(ai, pnum, UBI_UNKNOWN, |
| 1041 | UBI_UNKNOWN, ec, 1, &ai->erase); |
| 1042 | else |
| 1043 | err = add_to_list(ai, pnum, UBI_UNKNOWN, |
| 1044 | UBI_UNKNOWN, ec, 0, &ai->free); |
| 1045 | if (err) |
| 1046 | return err; |
| 1047 | goto adjust_mean_ec; |
| 1048 | default: |
| 1049 | ubi_err(ubi, "'ubi_io_read_vid_hdr()' returned unknown code %d", |
| 1050 | err); |
| 1051 | return -EINVAL; |
| 1052 | } |
| 1053 | |
| 1054 | vol_id = be32_to_cpu(vidh->vol_id); |
| 1055 | if (vol_id > UBI_MAX_VOLUMES && !vol_ignored(vol_id)) { |
| 1056 | int lnum = be32_to_cpu(vidh->lnum); |
| 1057 | |
| 1058 | /* Unsupported internal volume */ |
| 1059 | switch (vidh->compat) { |
| 1060 | case UBI_COMPAT_DELETE: |
| 1061 | ubi_msg(ubi, "\"delete\" compatible internal volume %d:%d found, will remove it", |
| 1062 | vol_id, lnum); |
| 1063 | |
| 1064 | err = add_to_list(ai, pnum, vol_id, lnum, |
| 1065 | ec, 1, &ai->erase); |
| 1066 | if (err) |
| 1067 | return err; |
| 1068 | return 0; |
| 1069 | |
| 1070 | case UBI_COMPAT_RO: |
| 1071 | ubi_msg(ubi, "read-only compatible internal volume %d:%d found, switch to read-only mode", |
| 1072 | vol_id, lnum); |
| 1073 | ubi->ro_mode = 1; |
| 1074 | break; |
| 1075 | |
| 1076 | case UBI_COMPAT_PRESERVE: |
| 1077 | ubi_msg(ubi, "\"preserve\" compatible internal volume %d:%d found", |
| 1078 | vol_id, lnum); |
| 1079 | err = add_to_list(ai, pnum, vol_id, lnum, |
| 1080 | ec, 0, &ai->alien); |
| 1081 | if (err) |
| 1082 | return err; |
| 1083 | return 0; |
| 1084 | |
| 1085 | case UBI_COMPAT_REJECT: |
| 1086 | ubi_err(ubi, "incompatible internal volume %d:%d found", |
| 1087 | vol_id, lnum); |
| 1088 | return -EINVAL; |
| 1089 | } |
| 1090 | } |
| 1091 | |
| 1092 | if (ec_err) |
| 1093 | ubi_warn(ubi, "valid VID header but corrupted EC header at PEB %d", |
| 1094 | pnum); |
| 1095 | |
| 1096 | if (ubi_is_fm_vol(vol_id)) |
| 1097 | err = add_fastmap(ai, pnum, vidh, ec); |
| 1098 | else |
| 1099 | err = ubi_add_to_av(ubi, ai, pnum, ec, vidh, bitflips); |
| 1100 | |
| 1101 | if (err) |
| 1102 | return err; |
| 1103 | |
| 1104 | adjust_mean_ec: |
| 1105 | if (!ec_err) { |
| 1106 | ai->ec_sum += ec; |
| 1107 | ai->ec_count += 1; |
| 1108 | if (ec > ai->max_ec) |
| 1109 | ai->max_ec = ec; |
| 1110 | if (ec < ai->min_ec) |
| 1111 | ai->min_ec = ec; |
| 1112 | } |
| 1113 | |
| 1114 | return 0; |
| 1115 | } |
| 1116 | |
| 1117 | /** |
| 1118 | * late_analysis - analyze the overall situation with PEB. |
| 1119 | * @ubi: UBI device description object |
| 1120 | * @ai: attaching information |
| 1121 | * |
| 1122 | * This is a helper function which takes a look what PEBs we have after we |
| 1123 | * gather information about all of them ("ai" is compete). It decides whether |
| 1124 | * the flash is empty and should be formatted of whether there are too many |
| 1125 | * corrupted PEBs and we should not attach this MTD device. Returns zero if we |
| 1126 | * should proceed with attaching the MTD device, and %-EINVAL if we should not. |
| 1127 | */ |
| 1128 | static int late_analysis(struct ubi_device *ubi, struct ubi_attach_info *ai) |
| 1129 | { |
| 1130 | struct ubi_ainf_peb *aeb; |
| 1131 | int max_corr, peb_count; |
| 1132 | |
| 1133 | peb_count = ubi->peb_count - ai->bad_peb_count - ai->alien_peb_count; |
| 1134 | max_corr = peb_count / 20 ?: 8; |
| 1135 | |
| 1136 | /* |
| 1137 | * Few corrupted PEBs is not a problem and may be just a result of |
| 1138 | * unclean reboots. However, many of them may indicate some problems |
| 1139 | * with the flash HW or driver. |
| 1140 | */ |
| 1141 | if (ai->corr_peb_count) { |
| 1142 | ubi_err(ubi, "%d PEBs are corrupted and preserved", |
| 1143 | ai->corr_peb_count); |
| 1144 | pr_err("Corrupted PEBs are:"); |
| 1145 | list_for_each_entry(aeb, &ai->corr, u.list) |
| 1146 | pr_cont(" %d", aeb->pnum); |
| 1147 | pr_cont("\n"); |
| 1148 | |
| 1149 | /* |
| 1150 | * If too many PEBs are corrupted, we refuse attaching, |
| 1151 | * otherwise, only print a warning. |
| 1152 | */ |
| 1153 | if (ai->corr_peb_count >= max_corr) { |
| 1154 | ubi_err(ubi, "too many corrupted PEBs, refusing"); |
| 1155 | return -EINVAL; |
| 1156 | } |
| 1157 | } |
| 1158 | |
| 1159 | if (ai->empty_peb_count + ai->maybe_bad_peb_count == peb_count) { |
| 1160 | /* |
| 1161 | * All PEBs are empty, or almost all - a couple PEBs look like |
| 1162 | * they may be bad PEBs which were not marked as bad yet. |
| 1163 | * |
| 1164 | * This piece of code basically tries to distinguish between |
| 1165 | * the following situations: |
| 1166 | * |
| 1167 | * 1. Flash is empty, but there are few bad PEBs, which are not |
| 1168 | * marked as bad so far, and which were read with error. We |
| 1169 | * want to go ahead and format this flash. While formatting, |
| 1170 | * the faulty PEBs will probably be marked as bad. |
| 1171 | * |
| 1172 | * 2. Flash contains non-UBI data and we do not want to format |
| 1173 | * it and destroy possibly important information. |
| 1174 | */ |
| 1175 | if (ai->maybe_bad_peb_count <= 2) { |
| 1176 | ai->is_empty = 1; |
| 1177 | ubi_msg(ubi, "empty MTD device detected"); |
| 1178 | get_random_bytes(&ubi->image_seq, |
| 1179 | sizeof(ubi->image_seq)); |
| 1180 | } else { |
| 1181 | ubi_err(ubi, "MTD device is not UBI-formatted and possibly contains non-UBI data - refusing it"); |
| 1182 | return -EINVAL; |
| 1183 | } |
| 1184 | |
| 1185 | } |
| 1186 | |
| 1187 | return 0; |
| 1188 | } |
| 1189 | |
| 1190 | /** |
| 1191 | * destroy_av - free volume attaching information. |
| 1192 | * @av: volume attaching information |
| 1193 | * @ai: attaching information |
| 1194 | * |
| 1195 | * This function destroys the volume attaching information. |
| 1196 | */ |
| 1197 | static void destroy_av(struct ubi_attach_info *ai, struct ubi_ainf_volume *av) |
| 1198 | { |
| 1199 | struct ubi_ainf_peb *aeb; |
| 1200 | struct rb_node *this = av->root.rb_node; |
| 1201 | |
| 1202 | while (this) { |
| 1203 | if (this->rb_left) |
| 1204 | this = this->rb_left; |
| 1205 | else if (this->rb_right) |
| 1206 | this = this->rb_right; |
| 1207 | else { |
| 1208 | aeb = rb_entry(this, struct ubi_ainf_peb, u.rb); |
| 1209 | this = rb_parent(this); |
| 1210 | if (this) { |
| 1211 | if (this->rb_left == &aeb->u.rb) |
| 1212 | this->rb_left = NULL; |
| 1213 | else |
| 1214 | this->rb_right = NULL; |
| 1215 | } |
| 1216 | |
| 1217 | kmem_cache_free(ai->aeb_slab_cache, aeb); |
| 1218 | } |
| 1219 | } |
| 1220 | kfree(av); |
| 1221 | } |
| 1222 | |
| 1223 | /** |
| 1224 | * destroy_ai - destroy attaching information. |
| 1225 | * @ai: attaching information |
| 1226 | */ |
| 1227 | static void destroy_ai(struct ubi_attach_info *ai) |
| 1228 | { |
| 1229 | struct ubi_ainf_peb *aeb, *aeb_tmp; |
| 1230 | struct ubi_ainf_volume *av; |
| 1231 | struct rb_node *rb; |
| 1232 | |
| 1233 | list_for_each_entry_safe(aeb, aeb_tmp, &ai->alien, u.list) { |
| 1234 | list_del(&aeb->u.list); |
| 1235 | kmem_cache_free(ai->aeb_slab_cache, aeb); |
| 1236 | } |
| 1237 | list_for_each_entry_safe(aeb, aeb_tmp, &ai->erase, u.list) { |
| 1238 | list_del(&aeb->u.list); |
| 1239 | kmem_cache_free(ai->aeb_slab_cache, aeb); |
| 1240 | } |
| 1241 | list_for_each_entry_safe(aeb, aeb_tmp, &ai->corr, u.list) { |
| 1242 | list_del(&aeb->u.list); |
| 1243 | kmem_cache_free(ai->aeb_slab_cache, aeb); |
| 1244 | } |
| 1245 | list_for_each_entry_safe(aeb, aeb_tmp, &ai->free, u.list) { |
| 1246 | list_del(&aeb->u.list); |
| 1247 | kmem_cache_free(ai->aeb_slab_cache, aeb); |
| 1248 | } |
| 1249 | list_for_each_entry_safe(aeb, aeb_tmp, &ai->fastmap, u.list) { |
| 1250 | list_del(&aeb->u.list); |
| 1251 | kmem_cache_free(ai->aeb_slab_cache, aeb); |
| 1252 | } |
| 1253 | |
| 1254 | /* Destroy the volume RB-tree */ |
| 1255 | rb = ai->volumes.rb_node; |
| 1256 | while (rb) { |
| 1257 | if (rb->rb_left) |
| 1258 | rb = rb->rb_left; |
| 1259 | else if (rb->rb_right) |
| 1260 | rb = rb->rb_right; |
| 1261 | else { |
| 1262 | av = rb_entry(rb, struct ubi_ainf_volume, rb); |
| 1263 | |
| 1264 | rb = rb_parent(rb); |
| 1265 | if (rb) { |
| 1266 | if (rb->rb_left == &av->rb) |
| 1267 | rb->rb_left = NULL; |
| 1268 | else |
| 1269 | rb->rb_right = NULL; |
| 1270 | } |
| 1271 | |
| 1272 | destroy_av(ai, av); |
| 1273 | } |
| 1274 | } |
| 1275 | |
| 1276 | kmem_cache_destroy(ai->aeb_slab_cache); |
| 1277 | kfree(ai); |
| 1278 | } |
| 1279 | |
| 1280 | /** |
| 1281 | * scan_all - scan entire MTD device. |
| 1282 | * @ubi: UBI device description object |
| 1283 | * @ai: attach info object |
| 1284 | * @start: start scanning at this PEB |
| 1285 | * |
| 1286 | * This function does full scanning of an MTD device and returns complete |
| 1287 | * information about it in form of a "struct ubi_attach_info" object. In case |
| 1288 | * of failure, an error code is returned. |
| 1289 | */ |
| 1290 | static int scan_all(struct ubi_device *ubi, struct ubi_attach_info *ai, |
| 1291 | int start) |
| 1292 | { |
| 1293 | int err, pnum; |
| 1294 | struct rb_node *rb1, *rb2; |
| 1295 | struct ubi_ainf_volume *av; |
| 1296 | struct ubi_ainf_peb *aeb; |
| 1297 | |
| 1298 | err = -ENOMEM; |
| 1299 | |
| 1300 | ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL); |
| 1301 | if (!ech) |
| 1302 | return err; |
| 1303 | |
| 1304 | vidh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL); |
| 1305 | if (!vidh) |
| 1306 | goto out_ech; |
| 1307 | |
| 1308 | for (pnum = start; pnum < ubi->peb_count; pnum++) { |
| 1309 | cond_resched(); |
| 1310 | |
| 1311 | dbg_gen("process PEB %d", pnum); |
| 1312 | err = scan_peb(ubi, ai, pnum, false); |
| 1313 | if (err < 0) |
| 1314 | goto out_vidh; |
| 1315 | } |
| 1316 | |
| 1317 | ubi_msg(ubi, "scanning is finished"); |
| 1318 | |
| 1319 | /* Calculate mean erase counter */ |
| 1320 | if (ai->ec_count) |
| 1321 | ai->mean_ec = div_u64(ai->ec_sum, ai->ec_count); |
| 1322 | |
| 1323 | err = late_analysis(ubi, ai); |
| 1324 | if (err) |
| 1325 | goto out_vidh; |
| 1326 | |
| 1327 | /* |
| 1328 | * In case of unknown erase counter we use the mean erase counter |
| 1329 | * value. |
| 1330 | */ |
| 1331 | ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb) { |
| 1332 | ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb) |
| 1333 | if (aeb->ec == UBI_UNKNOWN) |
| 1334 | aeb->ec = ai->mean_ec; |
| 1335 | } |
| 1336 | |
| 1337 | list_for_each_entry(aeb, &ai->free, u.list) { |
| 1338 | if (aeb->ec == UBI_UNKNOWN) |
| 1339 | aeb->ec = ai->mean_ec; |
| 1340 | } |
| 1341 | |
| 1342 | list_for_each_entry(aeb, &ai->corr, u.list) |
| 1343 | if (aeb->ec == UBI_UNKNOWN) |
| 1344 | aeb->ec = ai->mean_ec; |
| 1345 | |
| 1346 | list_for_each_entry(aeb, &ai->erase, u.list) |
| 1347 | if (aeb->ec == UBI_UNKNOWN) |
| 1348 | aeb->ec = ai->mean_ec; |
| 1349 | |
| 1350 | err = self_check_ai(ubi, ai); |
| 1351 | if (err) |
| 1352 | goto out_vidh; |
| 1353 | |
| 1354 | ubi_free_vid_hdr(ubi, vidh); |
| 1355 | kfree(ech); |
| 1356 | |
| 1357 | return 0; |
| 1358 | |
| 1359 | out_vidh: |
| 1360 | ubi_free_vid_hdr(ubi, vidh); |
| 1361 | out_ech: |
| 1362 | kfree(ech); |
| 1363 | return err; |
| 1364 | } |
| 1365 | |
| 1366 | static struct ubi_attach_info *alloc_ai(void) |
| 1367 | { |
| 1368 | struct ubi_attach_info *ai; |
| 1369 | |
| 1370 | ai = kzalloc(sizeof(struct ubi_attach_info), GFP_KERNEL); |
| 1371 | if (!ai) |
| 1372 | return ai; |
| 1373 | |
| 1374 | INIT_LIST_HEAD(&ai->corr); |
| 1375 | INIT_LIST_HEAD(&ai->free); |
| 1376 | INIT_LIST_HEAD(&ai->erase); |
| 1377 | INIT_LIST_HEAD(&ai->alien); |
| 1378 | INIT_LIST_HEAD(&ai->fastmap); |
| 1379 | ai->volumes = RB_ROOT; |
| 1380 | ai->aeb_slab_cache = kmem_cache_create("ubi_aeb_slab_cache", |
| 1381 | sizeof(struct ubi_ainf_peb), |
| 1382 | 0, 0, NULL); |
| 1383 | if (!ai->aeb_slab_cache) { |
| 1384 | kfree(ai); |
| 1385 | ai = NULL; |
| 1386 | } |
| 1387 | |
| 1388 | return ai; |
| 1389 | } |
| 1390 | |
| 1391 | #ifdef CONFIG_MTD_UBI_FASTMAP |
| 1392 | |
| 1393 | /** |
| 1394 | * scan_fast - try to find a fastmap and attach from it. |
| 1395 | * @ubi: UBI device description object |
| 1396 | * @ai: attach info object |
| 1397 | * |
| 1398 | * Returns 0 on success, negative return values indicate an internal |
| 1399 | * error. |
| 1400 | * UBI_NO_FASTMAP denotes that no fastmap was found. |
| 1401 | * UBI_BAD_FASTMAP denotes that the found fastmap was invalid. |
| 1402 | */ |
| 1403 | static int scan_fast(struct ubi_device *ubi, struct ubi_attach_info **ai) |
| 1404 | { |
| 1405 | int err, pnum; |
| 1406 | struct ubi_attach_info *scan_ai; |
| 1407 | |
| 1408 | err = -ENOMEM; |
| 1409 | |
| 1410 | scan_ai = alloc_ai(); |
| 1411 | if (!scan_ai) |
| 1412 | goto out; |
| 1413 | |
| 1414 | ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL); |
| 1415 | if (!ech) |
| 1416 | goto out_ai; |
| 1417 | |
| 1418 | vidh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL); |
| 1419 | if (!vidh) |
| 1420 | goto out_ech; |
| 1421 | |
| 1422 | for (pnum = 0; pnum < UBI_FM_MAX_START; pnum++) { |
| 1423 | cond_resched(); |
| 1424 | |
| 1425 | dbg_gen("process PEB %d", pnum); |
| 1426 | err = scan_peb(ubi, scan_ai, pnum, true); |
| 1427 | if (err < 0) |
| 1428 | goto out_vidh; |
| 1429 | } |
| 1430 | |
| 1431 | ubi_free_vid_hdr(ubi, vidh); |
| 1432 | kfree(ech); |
| 1433 | |
| 1434 | if (scan_ai->force_full_scan) |
| 1435 | err = UBI_NO_FASTMAP; |
| 1436 | else |
| 1437 | err = ubi_scan_fastmap(ubi, *ai, scan_ai); |
| 1438 | |
| 1439 | if (err) { |
| 1440 | /* |
| 1441 | * Didn't attach via fastmap, do a full scan but reuse what |
| 1442 | * we've aready scanned. |
| 1443 | */ |
| 1444 | destroy_ai(*ai); |
| 1445 | *ai = scan_ai; |
| 1446 | } else |
| 1447 | destroy_ai(scan_ai); |
| 1448 | |
| 1449 | return err; |
| 1450 | |
| 1451 | out_vidh: |
| 1452 | ubi_free_vid_hdr(ubi, vidh); |
| 1453 | out_ech: |
| 1454 | kfree(ech); |
| 1455 | out_ai: |
| 1456 | destroy_ai(scan_ai); |
| 1457 | out: |
| 1458 | return err; |
| 1459 | } |
| 1460 | |
| 1461 | #endif |
| 1462 | |
| 1463 | /** |
| 1464 | * ubi_attach - attach an MTD device. |
| 1465 | * @ubi: UBI device descriptor |
| 1466 | * @force_scan: if set to non-zero attach by scanning |
| 1467 | * |
| 1468 | * This function returns zero in case of success and a negative error code in |
| 1469 | * case of failure. |
| 1470 | */ |
| 1471 | int ubi_attach(struct ubi_device *ubi, int force_scan) |
| 1472 | { |
| 1473 | int err; |
| 1474 | struct ubi_attach_info *ai; |
| 1475 | |
| 1476 | ai = alloc_ai(); |
| 1477 | if (!ai) |
| 1478 | return -ENOMEM; |
| 1479 | |
| 1480 | #ifdef CONFIG_MTD_UBI_FASTMAP |
| 1481 | /* On small flash devices we disable fastmap in any case. */ |
| 1482 | if ((int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd) <= UBI_FM_MAX_START) { |
| 1483 | ubi->fm_disabled = 1; |
| 1484 | force_scan = 1; |
| 1485 | } |
| 1486 | |
| 1487 | if (force_scan) |
| 1488 | err = scan_all(ubi, ai, 0); |
| 1489 | else { |
| 1490 | err = scan_fast(ubi, &ai); |
| 1491 | if (err > 0 || mtd_is_eccerr(err)) { |
| 1492 | if (err != UBI_NO_FASTMAP) { |
| 1493 | destroy_ai(ai); |
| 1494 | ai = alloc_ai(); |
| 1495 | if (!ai) |
| 1496 | return -ENOMEM; |
| 1497 | |
| 1498 | err = scan_all(ubi, ai, 0); |
| 1499 | } else { |
| 1500 | err = scan_all(ubi, ai, UBI_FM_MAX_START); |
| 1501 | } |
| 1502 | } |
| 1503 | } |
| 1504 | #else |
| 1505 | err = scan_all(ubi, ai, 0); |
| 1506 | #endif |
| 1507 | if (err) |
| 1508 | goto out_ai; |
| 1509 | |
| 1510 | ubi->bad_peb_count = ai->bad_peb_count; |
| 1511 | ubi->good_peb_count = ubi->peb_count - ubi->bad_peb_count; |
| 1512 | ubi->corr_peb_count = ai->corr_peb_count; |
| 1513 | ubi->max_ec = ai->max_ec; |
| 1514 | ubi->mean_ec = ai->mean_ec; |
| 1515 | dbg_gen("max. sequence number: %llu", ai->max_sqnum); |
| 1516 | |
| 1517 | err = ubi_read_volume_table(ubi, ai); |
| 1518 | if (err) |
| 1519 | goto out_ai; |
| 1520 | |
| 1521 | err = ubi_wl_init(ubi, ai); |
| 1522 | if (err) |
| 1523 | goto out_vtbl; |
| 1524 | |
| 1525 | err = ubi_eba_init(ubi, ai); |
| 1526 | if (err) |
| 1527 | goto out_wl; |
| 1528 | |
| 1529 | #ifdef CONFIG_MTD_UBI_FASTMAP |
| 1530 | if (ubi->fm && ubi_dbg_chk_fastmap(ubi)) { |
| 1531 | struct ubi_attach_info *scan_ai; |
| 1532 | |
| 1533 | scan_ai = alloc_ai(); |
| 1534 | if (!scan_ai) { |
| 1535 | err = -ENOMEM; |
| 1536 | goto out_wl; |
| 1537 | } |
| 1538 | |
| 1539 | err = scan_all(ubi, scan_ai, 0); |
| 1540 | if (err) { |
| 1541 | destroy_ai(scan_ai); |
| 1542 | goto out_wl; |
| 1543 | } |
| 1544 | |
| 1545 | err = self_check_eba(ubi, ai, scan_ai); |
| 1546 | destroy_ai(scan_ai); |
| 1547 | |
| 1548 | if (err) |
| 1549 | goto out_wl; |
| 1550 | } |
| 1551 | #endif |
| 1552 | |
| 1553 | destroy_ai(ai); |
| 1554 | return 0; |
| 1555 | |
| 1556 | out_wl: |
| 1557 | ubi_wl_close(ubi); |
| 1558 | out_vtbl: |
| 1559 | ubi_free_internal_volumes(ubi); |
| 1560 | vfree(ubi->vtbl); |
| 1561 | out_ai: |
| 1562 | destroy_ai(ai); |
| 1563 | return err; |
| 1564 | } |
| 1565 | |
| 1566 | /** |
| 1567 | * self_check_ai - check the attaching information. |
| 1568 | * @ubi: UBI device description object |
| 1569 | * @ai: attaching information |
| 1570 | * |
| 1571 | * This function returns zero if the attaching information is all right, and a |
| 1572 | * negative error code if not or if an error occurred. |
| 1573 | */ |
| 1574 | static int self_check_ai(struct ubi_device *ubi, struct ubi_attach_info *ai) |
| 1575 | { |
| 1576 | int pnum, err, vols_found = 0; |
| 1577 | struct rb_node *rb1, *rb2; |
| 1578 | struct ubi_ainf_volume *av; |
| 1579 | struct ubi_ainf_peb *aeb, *last_aeb; |
| 1580 | uint8_t *buf; |
| 1581 | |
| 1582 | if (!ubi_dbg_chk_gen(ubi)) |
| 1583 | return 0; |
| 1584 | |
| 1585 | /* |
| 1586 | * At first, check that attaching information is OK. |
| 1587 | */ |
| 1588 | ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb) { |
| 1589 | int leb_count = 0; |
| 1590 | |
| 1591 | cond_resched(); |
| 1592 | |
| 1593 | vols_found += 1; |
| 1594 | |
| 1595 | if (ai->is_empty) { |
| 1596 | ubi_err(ubi, "bad is_empty flag"); |
| 1597 | goto bad_av; |
| 1598 | } |
| 1599 | |
| 1600 | if (av->vol_id < 0 || av->highest_lnum < 0 || |
| 1601 | av->leb_count < 0 || av->vol_type < 0 || av->used_ebs < 0 || |
| 1602 | av->data_pad < 0 || av->last_data_size < 0) { |
| 1603 | ubi_err(ubi, "negative values"); |
| 1604 | goto bad_av; |
| 1605 | } |
| 1606 | |
| 1607 | if (av->vol_id >= UBI_MAX_VOLUMES && |
| 1608 | av->vol_id < UBI_INTERNAL_VOL_START) { |
| 1609 | ubi_err(ubi, "bad vol_id"); |
| 1610 | goto bad_av; |
| 1611 | } |
| 1612 | |
| 1613 | if (av->vol_id > ai->highest_vol_id) { |
| 1614 | ubi_err(ubi, "highest_vol_id is %d, but vol_id %d is there", |
| 1615 | ai->highest_vol_id, av->vol_id); |
| 1616 | goto out; |
| 1617 | } |
| 1618 | |
| 1619 | if (av->vol_type != UBI_DYNAMIC_VOLUME && |
| 1620 | av->vol_type != UBI_STATIC_VOLUME) { |
| 1621 | ubi_err(ubi, "bad vol_type"); |
| 1622 | goto bad_av; |
| 1623 | } |
| 1624 | |
| 1625 | if (av->data_pad > ubi->leb_size / 2) { |
| 1626 | ubi_err(ubi, "bad data_pad"); |
| 1627 | goto bad_av; |
| 1628 | } |
| 1629 | |
| 1630 | last_aeb = NULL; |
| 1631 | ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb) { |
| 1632 | cond_resched(); |
| 1633 | |
| 1634 | last_aeb = aeb; |
| 1635 | leb_count += 1; |
| 1636 | |
| 1637 | if (aeb->pnum < 0 || aeb->ec < 0) { |
| 1638 | ubi_err(ubi, "negative values"); |
| 1639 | goto bad_aeb; |
| 1640 | } |
| 1641 | |
| 1642 | if (aeb->ec < ai->min_ec) { |
| 1643 | ubi_err(ubi, "bad ai->min_ec (%d), %d found", |
| 1644 | ai->min_ec, aeb->ec); |
| 1645 | goto bad_aeb; |
| 1646 | } |
| 1647 | |
| 1648 | if (aeb->ec > ai->max_ec) { |
| 1649 | ubi_err(ubi, "bad ai->max_ec (%d), %d found", |
| 1650 | ai->max_ec, aeb->ec); |
| 1651 | goto bad_aeb; |
| 1652 | } |
| 1653 | |
| 1654 | if (aeb->pnum >= ubi->peb_count) { |
| 1655 | ubi_err(ubi, "too high PEB number %d, total PEBs %d", |
| 1656 | aeb->pnum, ubi->peb_count); |
| 1657 | goto bad_aeb; |
| 1658 | } |
| 1659 | |
| 1660 | if (av->vol_type == UBI_STATIC_VOLUME) { |
| 1661 | if (aeb->lnum >= av->used_ebs) { |
| 1662 | ubi_err(ubi, "bad lnum or used_ebs"); |
| 1663 | goto bad_aeb; |
| 1664 | } |
| 1665 | } else { |
| 1666 | if (av->used_ebs != 0) { |
| 1667 | ubi_err(ubi, "non-zero used_ebs"); |
| 1668 | goto bad_aeb; |
| 1669 | } |
| 1670 | } |
| 1671 | |
| 1672 | if (aeb->lnum > av->highest_lnum) { |
| 1673 | ubi_err(ubi, "incorrect highest_lnum or lnum"); |
| 1674 | goto bad_aeb; |
| 1675 | } |
| 1676 | } |
| 1677 | |
| 1678 | if (av->leb_count != leb_count) { |
| 1679 | ubi_err(ubi, "bad leb_count, %d objects in the tree", |
| 1680 | leb_count); |
| 1681 | goto bad_av; |
| 1682 | } |
| 1683 | |
| 1684 | if (!last_aeb) |
| 1685 | continue; |
| 1686 | |
| 1687 | aeb = last_aeb; |
| 1688 | |
| 1689 | if (aeb->lnum != av->highest_lnum) { |
| 1690 | ubi_err(ubi, "bad highest_lnum"); |
| 1691 | goto bad_aeb; |
| 1692 | } |
| 1693 | } |
| 1694 | |
| 1695 | if (vols_found != ai->vols_found) { |
| 1696 | ubi_err(ubi, "bad ai->vols_found %d, should be %d", |
| 1697 | ai->vols_found, vols_found); |
| 1698 | goto out; |
| 1699 | } |
| 1700 | |
| 1701 | /* Check that attaching information is correct */ |
| 1702 | ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb) { |
| 1703 | last_aeb = NULL; |
| 1704 | ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb) { |
| 1705 | int vol_type; |
| 1706 | |
| 1707 | cond_resched(); |
| 1708 | |
| 1709 | last_aeb = aeb; |
| 1710 | |
| 1711 | err = ubi_io_read_vid_hdr(ubi, aeb->pnum, vidh, 1); |
| 1712 | if (err && err != UBI_IO_BITFLIPS) { |
| 1713 | ubi_err(ubi, "VID header is not OK (%d)", |
| 1714 | err); |
| 1715 | if (err > 0) |
| 1716 | err = -EIO; |
| 1717 | return err; |
| 1718 | } |
| 1719 | |
| 1720 | vol_type = vidh->vol_type == UBI_VID_DYNAMIC ? |
| 1721 | UBI_DYNAMIC_VOLUME : UBI_STATIC_VOLUME; |
| 1722 | if (av->vol_type != vol_type) { |
| 1723 | ubi_err(ubi, "bad vol_type"); |
| 1724 | goto bad_vid_hdr; |
| 1725 | } |
| 1726 | |
| 1727 | if (aeb->sqnum != be64_to_cpu(vidh->sqnum)) { |
| 1728 | ubi_err(ubi, "bad sqnum %llu", aeb->sqnum); |
| 1729 | goto bad_vid_hdr; |
| 1730 | } |
| 1731 | |
| 1732 | if (av->vol_id != be32_to_cpu(vidh->vol_id)) { |
| 1733 | ubi_err(ubi, "bad vol_id %d", av->vol_id); |
| 1734 | goto bad_vid_hdr; |
| 1735 | } |
| 1736 | |
| 1737 | if (av->compat != vidh->compat) { |
| 1738 | ubi_err(ubi, "bad compat %d", vidh->compat); |
| 1739 | goto bad_vid_hdr; |
| 1740 | } |
| 1741 | |
| 1742 | if (aeb->lnum != be32_to_cpu(vidh->lnum)) { |
| 1743 | ubi_err(ubi, "bad lnum %d", aeb->lnum); |
| 1744 | goto bad_vid_hdr; |
| 1745 | } |
| 1746 | |
| 1747 | if (av->used_ebs != be32_to_cpu(vidh->used_ebs)) { |
| 1748 | ubi_err(ubi, "bad used_ebs %d", av->used_ebs); |
| 1749 | goto bad_vid_hdr; |
| 1750 | } |
| 1751 | |
| 1752 | if (av->data_pad != be32_to_cpu(vidh->data_pad)) { |
| 1753 | ubi_err(ubi, "bad data_pad %d", av->data_pad); |
| 1754 | goto bad_vid_hdr; |
| 1755 | } |
| 1756 | } |
| 1757 | |
| 1758 | if (!last_aeb) |
| 1759 | continue; |
| 1760 | |
| 1761 | if (av->highest_lnum != be32_to_cpu(vidh->lnum)) { |
| 1762 | ubi_err(ubi, "bad highest_lnum %d", av->highest_lnum); |
| 1763 | goto bad_vid_hdr; |
| 1764 | } |
| 1765 | |
| 1766 | if (av->last_data_size != be32_to_cpu(vidh->data_size)) { |
| 1767 | ubi_err(ubi, "bad last_data_size %d", |
| 1768 | av->last_data_size); |
| 1769 | goto bad_vid_hdr; |
| 1770 | } |
| 1771 | } |
| 1772 | |
| 1773 | /* |
| 1774 | * Make sure that all the physical eraseblocks are in one of the lists |
| 1775 | * or trees. |
| 1776 | */ |
| 1777 | buf = kzalloc(ubi->peb_count, GFP_KERNEL); |
| 1778 | if (!buf) |
| 1779 | return -ENOMEM; |
| 1780 | |
| 1781 | for (pnum = 0; pnum < ubi->peb_count; pnum++) { |
| 1782 | err = ubi_io_is_bad(ubi, pnum); |
| 1783 | if (err < 0) { |
| 1784 | kfree(buf); |
| 1785 | return err; |
| 1786 | } else if (err) |
| 1787 | buf[pnum] = 1; |
| 1788 | } |
| 1789 | |
| 1790 | ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb) |
| 1791 | ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb) |
| 1792 | buf[aeb->pnum] = 1; |
| 1793 | |
| 1794 | list_for_each_entry(aeb, &ai->free, u.list) |
| 1795 | buf[aeb->pnum] = 1; |
| 1796 | |
| 1797 | list_for_each_entry(aeb, &ai->corr, u.list) |
| 1798 | buf[aeb->pnum] = 1; |
| 1799 | |
| 1800 | list_for_each_entry(aeb, &ai->erase, u.list) |
| 1801 | buf[aeb->pnum] = 1; |
| 1802 | |
| 1803 | list_for_each_entry(aeb, &ai->alien, u.list) |
| 1804 | buf[aeb->pnum] = 1; |
| 1805 | |
| 1806 | err = 0; |
| 1807 | for (pnum = 0; pnum < ubi->peb_count; pnum++) |
| 1808 | if (!buf[pnum]) { |
| 1809 | ubi_err(ubi, "PEB %d is not referred", pnum); |
| 1810 | err = 1; |
| 1811 | } |
| 1812 | |
| 1813 | kfree(buf); |
| 1814 | if (err) |
| 1815 | goto out; |
| 1816 | return 0; |
| 1817 | |
| 1818 | bad_aeb: |
| 1819 | ubi_err(ubi, "bad attaching information about LEB %d", aeb->lnum); |
| 1820 | ubi_dump_aeb(aeb, 0); |
| 1821 | ubi_dump_av(av); |
| 1822 | goto out; |
| 1823 | |
| 1824 | bad_av: |
| 1825 | ubi_err(ubi, "bad attaching information about volume %d", av->vol_id); |
| 1826 | ubi_dump_av(av); |
| 1827 | goto out; |
| 1828 | |
| 1829 | bad_vid_hdr: |
| 1830 | ubi_err(ubi, "bad attaching information about volume %d", av->vol_id); |
| 1831 | ubi_dump_av(av); |
| 1832 | ubi_dump_vid_hdr(vidh); |
| 1833 | |
| 1834 | out: |
| 1835 | dump_stack(); |
| 1836 | return -EINVAL; |
| 1837 | } |