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 * The UBI Eraseblock Association (EBA) sub-system. 23 * 24 * This sub-system is responsible for I/O to/from logical eraseblock. 25 * 26 * Although in this implementation the EBA table is fully kept and managed in 27 * RAM, which assumes poor scalability, it might be (partially) maintained on 28 * flash in future implementations. 29 * 30 * The EBA sub-system implements per-logical eraseblock locking. Before 31 * accessing a logical eraseblock it is locked for reading or writing. The 32 * per-logical eraseblock locking is implemented by means of the lock tree. The 33 * lock tree is an RB-tree which refers all the currently locked logical 34 * eraseblocks. The lock tree elements are &struct ubi_ltree_entry objects. 35 * They are indexed by (@vol_id, @lnum) pairs. 36 * 37 * EBA also maintains the global sequence counter which is incremented each 38 * time a logical eraseblock is mapped to a physical eraseblock and it is 39 * stored in the volume identifier header. This means that each VID header has 40 * a unique sequence number. The sequence number is only increased an we assume 41 * 64 bits is enough to never overflow. 42 */ 43 44#include <linux/slab.h> 45#include <linux/crc32.h> 46#include <linux/err.h> 47#include "ubi.h" 48 49/* Number of physical eraseblocks reserved for atomic LEB change operation */ 50#define EBA_RESERVED_PEBS 1 51 52/** 53 * next_sqnum - get next sequence number. 54 * @ubi: UBI device description object 55 * 56 * This function returns next sequence number to use, which is just the current 57 * global sequence counter value. It also increases the global sequence 58 * counter. 59 */ 60unsigned long long ubi_next_sqnum(struct ubi_device *ubi) 61{ 62 unsigned long long sqnum; 63 64 spin_lock(&ubi->ltree_lock); 65 sqnum = ubi->global_sqnum++; 66 spin_unlock(&ubi->ltree_lock); 67 68 return sqnum; 69} 70 71/** 72 * ubi_get_compat - get compatibility flags of a volume. 73 * @ubi: UBI device description object 74 * @vol_id: volume ID 75 * 76 * This function returns compatibility flags for an internal volume. User 77 * volumes have no compatibility flags, so %0 is returned. 78 */ 79static int ubi_get_compat(const struct ubi_device *ubi, int vol_id) 80{ 81 if (vol_id == UBI_LAYOUT_VOLUME_ID) 82 return UBI_LAYOUT_VOLUME_COMPAT; 83 return 0; 84} 85 86/** 87 * ltree_lookup - look up the lock tree. 88 * @ubi: UBI device description object 89 * @vol_id: volume ID 90 * @lnum: logical eraseblock number 91 * 92 * This function returns a pointer to the corresponding &struct ubi_ltree_entry 93 * object if the logical eraseblock is locked and %NULL if it is not. 94 * @ubi->ltree_lock has to be locked. 95 */ 96static struct ubi_ltree_entry *ltree_lookup(struct ubi_device *ubi, int vol_id, 97 int lnum) 98{ 99 struct rb_node *p; 100 101 p = ubi->ltree.rb_node; 102 while (p) { 103 struct ubi_ltree_entry *le; 104 105 le = rb_entry(p, struct ubi_ltree_entry, rb); 106 107 if (vol_id < le->vol_id) 108 p = p->rb_left; 109 else if (vol_id > le->vol_id) 110 p = p->rb_right; 111 else { 112 if (lnum < le->lnum) 113 p = p->rb_left; 114 else if (lnum > le->lnum) 115 p = p->rb_right; 116 else 117 return le; 118 } 119 } 120 121 return NULL; 122} 123 124/** 125 * ltree_add_entry - add new entry to the lock tree. 126 * @ubi: UBI device description object 127 * @vol_id: volume ID 128 * @lnum: logical eraseblock number 129 * 130 * This function adds new entry for logical eraseblock (@vol_id, @lnum) to the 131 * lock tree. If such entry is already there, its usage counter is increased. 132 * Returns pointer to the lock tree entry or %-ENOMEM if memory allocation 133 * failed. 134 */ 135static struct ubi_ltree_entry *ltree_add_entry(struct ubi_device *ubi, 136 int vol_id, int lnum) 137{ 138 struct ubi_ltree_entry *le, *le1, *le_free; 139 140 le = kmalloc(sizeof(struct ubi_ltree_entry), GFP_NOFS); 141 if (!le) 142 return ERR_PTR(-ENOMEM); 143 144 le->users = 0; 145 init_rwsem(&le->mutex); 146 le->vol_id = vol_id; 147 le->lnum = lnum; 148 149 spin_lock(&ubi->ltree_lock); 150 le1 = ltree_lookup(ubi, vol_id, lnum); 151 152 if (le1) { 153 /* 154 * This logical eraseblock is already locked. The newly 155 * allocated lock entry is not needed. 156 */ 157 le_free = le; 158 le = le1; 159 } else { 160 struct rb_node **p, *parent = NULL; 161 162 /* 163 * No lock entry, add the newly allocated one to the 164 * @ubi->ltree RB-tree. 165 */ 166 le_free = NULL; 167 168 p = &ubi->ltree.rb_node; 169 while (*p) { 170 parent = *p; 171 le1 = rb_entry(parent, struct ubi_ltree_entry, rb); 172 173 if (vol_id < le1->vol_id) 174 p = &(*p)->rb_left; 175 else if (vol_id > le1->vol_id) 176 p = &(*p)->rb_right; 177 else { 178 ubi_assert(lnum != le1->lnum); 179 if (lnum < le1->lnum) 180 p = &(*p)->rb_left; 181 else 182 p = &(*p)->rb_right; 183 } 184 } 185 186 rb_link_node(&le->rb, parent, p); 187 rb_insert_color(&le->rb, &ubi->ltree); 188 } 189 le->users += 1; 190 spin_unlock(&ubi->ltree_lock); 191 192 kfree(le_free); 193 return le; 194} 195 196/** 197 * leb_read_lock - lock logical eraseblock for reading. 198 * @ubi: UBI device description object 199 * @vol_id: volume ID 200 * @lnum: logical eraseblock number 201 * 202 * This function locks a logical eraseblock for reading. Returns zero in case 203 * of success and a negative error code in case of failure. 204 */ 205static int leb_read_lock(struct ubi_device *ubi, int vol_id, int lnum) 206{ 207 struct ubi_ltree_entry *le; 208 209 le = ltree_add_entry(ubi, vol_id, lnum); 210 if (IS_ERR(le)) 211 return PTR_ERR(le); 212 down_read(&le->mutex); 213 return 0; 214} 215 216/** 217 * leb_read_unlock - unlock logical eraseblock. 218 * @ubi: UBI device description object 219 * @vol_id: volume ID 220 * @lnum: logical eraseblock number 221 */ 222static void leb_read_unlock(struct ubi_device *ubi, int vol_id, int lnum) 223{ 224 struct ubi_ltree_entry *le; 225 226 spin_lock(&ubi->ltree_lock); 227 le = ltree_lookup(ubi, vol_id, lnum); 228 le->users -= 1; 229 ubi_assert(le->users >= 0); 230 up_read(&le->mutex); 231 if (le->users == 0) { 232 rb_erase(&le->rb, &ubi->ltree); 233 kfree(le); 234 } 235 spin_unlock(&ubi->ltree_lock); 236} 237 238/** 239 * leb_write_lock - lock logical eraseblock for writing. 240 * @ubi: UBI device description object 241 * @vol_id: volume ID 242 * @lnum: logical eraseblock number 243 * 244 * This function locks a logical eraseblock for writing. Returns zero in case 245 * of success and a negative error code in case of failure. 246 */ 247static int leb_write_lock(struct ubi_device *ubi, int vol_id, int lnum) 248{ 249 struct ubi_ltree_entry *le; 250 251 le = ltree_add_entry(ubi, vol_id, lnum); 252 if (IS_ERR(le)) 253 return PTR_ERR(le); 254 down_write(&le->mutex); 255 return 0; 256} 257 258/** 259 * leb_write_lock - lock logical eraseblock for writing. 260 * @ubi: UBI device description object 261 * @vol_id: volume ID 262 * @lnum: logical eraseblock number 263 * 264 * This function locks a logical eraseblock for writing if there is no 265 * contention and does nothing if there is contention. Returns %0 in case of 266 * success, %1 in case of contention, and and a negative error code in case of 267 * failure. 268 */ 269static int leb_write_trylock(struct ubi_device *ubi, int vol_id, int lnum) 270{ 271 struct ubi_ltree_entry *le; 272 273 le = ltree_add_entry(ubi, vol_id, lnum); 274 if (IS_ERR(le)) 275 return PTR_ERR(le); 276 if (down_write_trylock(&le->mutex)) 277 return 0; 278 279 /* Contention, cancel */ 280 spin_lock(&ubi->ltree_lock); 281 le->users -= 1; 282 ubi_assert(le->users >= 0); 283 if (le->users == 0) { 284 rb_erase(&le->rb, &ubi->ltree); 285 kfree(le); 286 } 287 spin_unlock(&ubi->ltree_lock); 288 289 return 1; 290} 291 292/** 293 * leb_write_unlock - unlock logical eraseblock. 294 * @ubi: UBI device description object 295 * @vol_id: volume ID 296 * @lnum: logical eraseblock number 297 */ 298static void leb_write_unlock(struct ubi_device *ubi, int vol_id, int lnum) 299{ 300 struct ubi_ltree_entry *le; 301 302 spin_lock(&ubi->ltree_lock); 303 le = ltree_lookup(ubi, vol_id, lnum); 304 le->users -= 1; 305 ubi_assert(le->users >= 0); 306 up_write(&le->mutex); 307 if (le->users == 0) { 308 rb_erase(&le->rb, &ubi->ltree); 309 kfree(le); 310 } 311 spin_unlock(&ubi->ltree_lock); 312} 313 314/** 315 * ubi_eba_unmap_leb - un-map logical eraseblock. 316 * @ubi: UBI device description object 317 * @vol: volume description object 318 * @lnum: logical eraseblock number 319 * 320 * This function un-maps logical eraseblock @lnum and schedules corresponding 321 * physical eraseblock for erasure. Returns zero in case of success and a 322 * negative error code in case of failure. 323 */ 324int ubi_eba_unmap_leb(struct ubi_device *ubi, struct ubi_volume *vol, 325 int lnum) 326{ 327 int err, pnum, vol_id = vol->vol_id; 328 329 if (ubi->ro_mode) 330 return -EROFS; 331 332 err = leb_write_lock(ubi, vol_id, lnum); 333 if (err) 334 return err; 335 336 pnum = vol->eba_tbl[lnum]; 337 if (pnum < 0) 338 /* This logical eraseblock is already unmapped */ 339 goto out_unlock; 340 341 dbg_eba("erase LEB %d:%d, PEB %d", vol_id, lnum, pnum); 342 343 down_read(&ubi->fm_eba_sem); 344 vol->eba_tbl[lnum] = UBI_LEB_UNMAPPED; 345 up_read(&ubi->fm_eba_sem); 346 err = ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 0); 347 348out_unlock: 349 leb_write_unlock(ubi, vol_id, lnum); 350 return err; 351} 352 353/** 354 * ubi_eba_read_leb - read data. 355 * @ubi: UBI device description object 356 * @vol: volume description object 357 * @lnum: logical eraseblock number 358 * @buf: buffer to store the read data 359 * @offset: offset from where to read 360 * @len: how many bytes to read 361 * @check: data CRC check flag 362 * 363 * If the logical eraseblock @lnum is unmapped, @buf is filled with 0xFF 364 * bytes. The @check flag only makes sense for static volumes and forces 365 * eraseblock data CRC checking. 366 * 367 * In case of success this function returns zero. In case of a static volume, 368 * if data CRC mismatches - %-EBADMSG is returned. %-EBADMSG may also be 369 * returned for any volume type if an ECC error was detected by the MTD device 370 * driver. Other negative error cored may be returned in case of other errors. 371 */ 372int ubi_eba_read_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum, 373 void *buf, int offset, int len, int check) 374{ 375 int err, pnum, scrub = 0, vol_id = vol->vol_id; 376 struct ubi_vid_hdr *vid_hdr; 377 uint32_t uninitialized_var(crc); 378 379 err = leb_read_lock(ubi, vol_id, lnum); 380 if (err) 381 return err; 382 383 pnum = vol->eba_tbl[lnum]; 384 if (pnum < 0) { 385 /* 386 * The logical eraseblock is not mapped, fill the whole buffer 387 * with 0xFF bytes. The exception is static volumes for which 388 * it is an error to read unmapped logical eraseblocks. 389 */ 390 dbg_eba("read %d bytes from offset %d of LEB %d:%d (unmapped)", 391 len, offset, vol_id, lnum); 392 leb_read_unlock(ubi, vol_id, lnum); 393 ubi_assert(vol->vol_type != UBI_STATIC_VOLUME); 394 memset(buf, 0xFF, len); 395 return 0; 396 } 397 398 dbg_eba("read %d bytes from offset %d of LEB %d:%d, PEB %d", 399 len, offset, vol_id, lnum, pnum); 400 401 if (vol->vol_type == UBI_DYNAMIC_VOLUME) 402 check = 0; 403 404retry: 405 if (check) { 406 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS); 407 if (!vid_hdr) { 408 err = -ENOMEM; 409 goto out_unlock; 410 } 411 412 err = ubi_io_read_vid_hdr(ubi, pnum, vid_hdr, 1); 413 if (err && err != UBI_IO_BITFLIPS) { 414 if (err > 0) { 415 /* 416 * The header is either absent or corrupted. 417 * The former case means there is a bug - 418 * switch to read-only mode just in case. 419 * The latter case means a real corruption - we 420 * may try to recover data. FIXME: but this is 421 * not implemented. 422 */ 423 if (err == UBI_IO_BAD_HDR_EBADMSG || 424 err == UBI_IO_BAD_HDR) { 425 ubi_warn(ubi, "corrupted VID header at PEB %d, LEB %d:%d", 426 pnum, vol_id, lnum); 427 err = -EBADMSG; 428 } else { 429 /* 430 * Ending up here in the non-Fastmap case 431 * is a clear bug as the VID header had to 432 * be present at scan time to have it referenced. 433 * With fastmap the story is more complicated. 434 * Fastmap has the mapping info without the need 435 * of a full scan. So the LEB could have been 436 * unmapped, Fastmap cannot know this and keeps 437 * the LEB referenced. 438 * This is valid and works as the layer above UBI 439 * has to do bookkeeping about used/referenced 440 * LEBs in any case. 441 */ 442 if (ubi->fast_attach) { 443 err = -EBADMSG; 444 } else { 445 err = -EINVAL; 446 ubi_ro_mode(ubi); 447 } 448 } 449 } 450 goto out_free; 451 } else if (err == UBI_IO_BITFLIPS) 452 scrub = 1; 453 454 ubi_assert(lnum < be32_to_cpu(vid_hdr->used_ebs)); 455 ubi_assert(len == be32_to_cpu(vid_hdr->data_size)); 456 457 crc = be32_to_cpu(vid_hdr->data_crc); 458 ubi_free_vid_hdr(ubi, vid_hdr); 459 } 460 461 err = ubi_io_read_data(ubi, buf, pnum, offset, len); 462 if (err) { 463 if (err == UBI_IO_BITFLIPS) 464 scrub = 1; 465 else if (mtd_is_eccerr(err)) { 466 if (vol->vol_type == UBI_DYNAMIC_VOLUME) 467 goto out_unlock; 468 scrub = 1; 469 if (!check) { 470 ubi_msg(ubi, "force data checking"); 471 check = 1; 472 goto retry; 473 } 474 } else 475 goto out_unlock; 476 } 477 478 if (check) { 479 uint32_t crc1 = crc32(UBI_CRC32_INIT, buf, len); 480 if (crc1 != crc) { 481 ubi_warn(ubi, "CRC error: calculated %#08x, must be %#08x", 482 crc1, crc); 483 err = -EBADMSG; 484 goto out_unlock; 485 } 486 } 487 488 if (scrub) 489 err = ubi_wl_scrub_peb(ubi, pnum); 490 491 leb_read_unlock(ubi, vol_id, lnum); 492 return err; 493 494out_free: 495 ubi_free_vid_hdr(ubi, vid_hdr); 496out_unlock: 497 leb_read_unlock(ubi, vol_id, lnum); 498 return err; 499} 500 501/** 502 * ubi_eba_read_leb_sg - read data into a scatter gather list. 503 * @ubi: UBI device description object 504 * @vol: volume description object 505 * @lnum: logical eraseblock number 506 * @sgl: UBI scatter gather list to store the read data 507 * @offset: offset from where to read 508 * @len: how many bytes to read 509 * @check: data CRC check flag 510 * 511 * This function works exactly like ubi_eba_read_leb(). But instead of 512 * storing the read data into a buffer it writes to an UBI scatter gather 513 * list. 514 */ 515int ubi_eba_read_leb_sg(struct ubi_device *ubi, struct ubi_volume *vol, 516 struct ubi_sgl *sgl, int lnum, int offset, int len, 517 int check) 518{ 519 int to_read; 520 int ret; 521 struct scatterlist *sg; 522 523 for (;;) { 524 ubi_assert(sgl->list_pos < UBI_MAX_SG_COUNT); 525 sg = &sgl->sg[sgl->list_pos]; 526 if (len < sg->length - sgl->page_pos) 527 to_read = len; 528 else 529 to_read = sg->length - sgl->page_pos; 530 531 ret = ubi_eba_read_leb(ubi, vol, lnum, 532 sg_virt(sg) + sgl->page_pos, offset, 533 to_read, check); 534 if (ret < 0) 535 return ret; 536 537 offset += to_read; 538 len -= to_read; 539 if (!len) { 540 sgl->page_pos += to_read; 541 if (sgl->page_pos == sg->length) { 542 sgl->list_pos++; 543 sgl->page_pos = 0; 544 } 545 546 break; 547 } 548 549 sgl->list_pos++; 550 sgl->page_pos = 0; 551 } 552 553 return ret; 554} 555 556/** 557 * recover_peb - recover from write failure. 558 * @ubi: UBI device description object 559 * @pnum: the physical eraseblock to recover 560 * @vol_id: volume ID 561 * @lnum: logical eraseblock number 562 * @buf: data which was not written because of the write failure 563 * @offset: offset of the failed write 564 * @len: how many bytes should have been written 565 * 566 * This function is called in case of a write failure and moves all good data 567 * from the potentially bad physical eraseblock to a good physical eraseblock. 568 * This function also writes the data which was not written due to the failure. 569 * Returns new physical eraseblock number in case of success, and a negative 570 * error code in case of failure. 571 */ 572static int recover_peb(struct ubi_device *ubi, int pnum, int vol_id, int lnum, 573 const void *buf, int offset, int len) 574{ 575 int err, idx = vol_id2idx(ubi, vol_id), new_pnum, data_size, tries = 0; 576 struct ubi_volume *vol = ubi->volumes[idx]; 577 struct ubi_vid_hdr *vid_hdr; 578 579 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS); 580 if (!vid_hdr) 581 return -ENOMEM; 582 583retry: 584 new_pnum = ubi_wl_get_peb(ubi); 585 if (new_pnum < 0) { 586 ubi_free_vid_hdr(ubi, vid_hdr); 587 up_read(&ubi->fm_eba_sem); 588 return new_pnum; 589 } 590 591 ubi_msg(ubi, "recover PEB %d, move data to PEB %d", 592 pnum, new_pnum); 593 594 err = ubi_io_read_vid_hdr(ubi, pnum, vid_hdr, 1); 595 if (err && err != UBI_IO_BITFLIPS) { 596 if (err > 0) 597 err = -EIO; 598 up_read(&ubi->fm_eba_sem); 599 goto out_put; 600 } 601 602 vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); 603 err = ubi_io_write_vid_hdr(ubi, new_pnum, vid_hdr); 604 if (err) { 605 up_read(&ubi->fm_eba_sem); 606 goto write_error; 607 } 608 609 data_size = offset + len; 610 mutex_lock(&ubi->buf_mutex); 611 memset(ubi->peb_buf + offset, 0xFF, len); 612 613 /* Read everything before the area where the write failure happened */ 614 if (offset > 0) { 615 err = ubi_io_read_data(ubi, ubi->peb_buf, pnum, 0, offset); 616 if (err && err != UBI_IO_BITFLIPS) { 617 up_read(&ubi->fm_eba_sem); 618 goto out_unlock; 619 } 620 } 621 622 memcpy(ubi->peb_buf + offset, buf, len); 623 624 err = ubi_io_write_data(ubi, ubi->peb_buf, new_pnum, 0, data_size); 625 if (err) { 626 mutex_unlock(&ubi->buf_mutex); 627 up_read(&ubi->fm_eba_sem); 628 goto write_error; 629 } 630 631 mutex_unlock(&ubi->buf_mutex); 632 ubi_free_vid_hdr(ubi, vid_hdr); 633 634 vol->eba_tbl[lnum] = new_pnum; 635 up_read(&ubi->fm_eba_sem); 636 ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 1); 637 638 ubi_msg(ubi, "data was successfully recovered"); 639 return 0; 640 641out_unlock: 642 mutex_unlock(&ubi->buf_mutex); 643out_put: 644 ubi_wl_put_peb(ubi, vol_id, lnum, new_pnum, 1); 645 ubi_free_vid_hdr(ubi, vid_hdr); 646 return err; 647 648write_error: 649 /* 650 * Bad luck? This physical eraseblock is bad too? Crud. Let's try to 651 * get another one. 652 */ 653 ubi_warn(ubi, "failed to write to PEB %d", new_pnum); 654 ubi_wl_put_peb(ubi, vol_id, lnum, new_pnum, 1); 655 if (++tries > UBI_IO_RETRIES) { 656 ubi_free_vid_hdr(ubi, vid_hdr); 657 return err; 658 } 659 ubi_msg(ubi, "try again"); 660 goto retry; 661} 662 663/** 664 * ubi_eba_write_leb - write data to dynamic volume. 665 * @ubi: UBI device description object 666 * @vol: volume description object 667 * @lnum: logical eraseblock number 668 * @buf: the data to write 669 * @offset: offset within the logical eraseblock where to write 670 * @len: how many bytes to write 671 * 672 * This function writes data to logical eraseblock @lnum of a dynamic volume 673 * @vol. Returns zero in case of success and a negative error code in case 674 * of failure. In case of error, it is possible that something was still 675 * written to the flash media, but may be some garbage. 676 */ 677int ubi_eba_write_leb(struct ubi_device *ubi, struct ubi_volume *vol, int lnum, 678 const void *buf, int offset, int len) 679{ 680 int err, pnum, tries = 0, vol_id = vol->vol_id; 681 struct ubi_vid_hdr *vid_hdr; 682 683 if (ubi->ro_mode) 684 return -EROFS; 685 686 err = leb_write_lock(ubi, vol_id, lnum); 687 if (err) 688 return err; 689 690 pnum = vol->eba_tbl[lnum]; 691 if (pnum >= 0) { 692 dbg_eba("write %d bytes at offset %d of LEB %d:%d, PEB %d", 693 len, offset, vol_id, lnum, pnum); 694 695 err = ubi_io_write_data(ubi, buf, pnum, offset, len); 696 if (err) { 697 ubi_warn(ubi, "failed to write data to PEB %d", pnum); 698 if (err == -EIO && ubi->bad_allowed) 699 err = recover_peb(ubi, pnum, vol_id, lnum, buf, 700 offset, len); 701 if (err) 702 ubi_ro_mode(ubi); 703 } 704 leb_write_unlock(ubi, vol_id, lnum); 705 return err; 706 } 707 708 /* 709 * The logical eraseblock is not mapped. We have to get a free physical 710 * eraseblock and write the volume identifier header there first. 711 */ 712 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS); 713 if (!vid_hdr) { 714 leb_write_unlock(ubi, vol_id, lnum); 715 return -ENOMEM; 716 } 717 718 vid_hdr->vol_type = UBI_VID_DYNAMIC; 719 vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); 720 vid_hdr->vol_id = cpu_to_be32(vol_id); 721 vid_hdr->lnum = cpu_to_be32(lnum); 722 vid_hdr->compat = ubi_get_compat(ubi, vol_id); 723 vid_hdr->data_pad = cpu_to_be32(vol->data_pad); 724 725retry: 726 pnum = ubi_wl_get_peb(ubi); 727 if (pnum < 0) { 728 ubi_free_vid_hdr(ubi, vid_hdr); 729 leb_write_unlock(ubi, vol_id, lnum); 730 up_read(&ubi->fm_eba_sem); 731 return pnum; 732 } 733 734 dbg_eba("write VID hdr and %d bytes at offset %d of LEB %d:%d, PEB %d", 735 len, offset, vol_id, lnum, pnum); 736 737 err = ubi_io_write_vid_hdr(ubi, pnum, vid_hdr); 738 if (err) { 739 ubi_warn(ubi, "failed to write VID header to LEB %d:%d, PEB %d", 740 vol_id, lnum, pnum); 741 up_read(&ubi->fm_eba_sem); 742 goto write_error; 743 } 744 745 if (len) { 746 err = ubi_io_write_data(ubi, buf, pnum, offset, len); 747 if (err) { 748 ubi_warn(ubi, "failed to write %d bytes at offset %d of LEB %d:%d, PEB %d", 749 len, offset, vol_id, lnum, pnum); 750 up_read(&ubi->fm_eba_sem); 751 goto write_error; 752 } 753 } 754 755 vol->eba_tbl[lnum] = pnum; 756 up_read(&ubi->fm_eba_sem); 757 758 leb_write_unlock(ubi, vol_id, lnum); 759 ubi_free_vid_hdr(ubi, vid_hdr); 760 return 0; 761 762write_error: 763 if (err != -EIO || !ubi->bad_allowed) { 764 ubi_ro_mode(ubi); 765 leb_write_unlock(ubi, vol_id, lnum); 766 ubi_free_vid_hdr(ubi, vid_hdr); 767 return err; 768 } 769 770 /* 771 * Fortunately, this is the first write operation to this physical 772 * eraseblock, so just put it and request a new one. We assume that if 773 * this physical eraseblock went bad, the erase code will handle that. 774 */ 775 err = ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 1); 776 if (err || ++tries > UBI_IO_RETRIES) { 777 ubi_ro_mode(ubi); 778 leb_write_unlock(ubi, vol_id, lnum); 779 ubi_free_vid_hdr(ubi, vid_hdr); 780 return err; 781 } 782 783 vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); 784 ubi_msg(ubi, "try another PEB"); 785 goto retry; 786} 787 788/** 789 * ubi_eba_write_leb_st - write data to static volume. 790 * @ubi: UBI device description object 791 * @vol: volume description object 792 * @lnum: logical eraseblock number 793 * @buf: data to write 794 * @len: how many bytes to write 795 * @used_ebs: how many logical eraseblocks will this volume contain 796 * 797 * This function writes data to logical eraseblock @lnum of static volume 798 * @vol. The @used_ebs argument should contain total number of logical 799 * eraseblock in this static volume. 800 * 801 * When writing to the last logical eraseblock, the @len argument doesn't have 802 * to be aligned to the minimal I/O unit size. Instead, it has to be equivalent 803 * to the real data size, although the @buf buffer has to contain the 804 * alignment. In all other cases, @len has to be aligned. 805 * 806 * It is prohibited to write more than once to logical eraseblocks of static 807 * volumes. This function returns zero in case of success and a negative error 808 * code in case of failure. 809 */ 810int ubi_eba_write_leb_st(struct ubi_device *ubi, struct ubi_volume *vol, 811 int lnum, const void *buf, int len, int used_ebs) 812{ 813 int err, pnum, tries = 0, data_size = len, vol_id = vol->vol_id; 814 struct ubi_vid_hdr *vid_hdr; 815 uint32_t crc; 816 817 if (ubi->ro_mode) 818 return -EROFS; 819 820 if (lnum == used_ebs - 1) 821 /* If this is the last LEB @len may be unaligned */ 822 len = ALIGN(data_size, ubi->min_io_size); 823 else 824 ubi_assert(!(len & (ubi->min_io_size - 1))); 825 826 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS); 827 if (!vid_hdr) 828 return -ENOMEM; 829 830 err = leb_write_lock(ubi, vol_id, lnum); 831 if (err) { 832 ubi_free_vid_hdr(ubi, vid_hdr); 833 return err; 834 } 835 836 vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); 837 vid_hdr->vol_id = cpu_to_be32(vol_id); 838 vid_hdr->lnum = cpu_to_be32(lnum); 839 vid_hdr->compat = ubi_get_compat(ubi, vol_id); 840 vid_hdr->data_pad = cpu_to_be32(vol->data_pad); 841 842 crc = crc32(UBI_CRC32_INIT, buf, data_size); 843 vid_hdr->vol_type = UBI_VID_STATIC; 844 vid_hdr->data_size = cpu_to_be32(data_size); 845 vid_hdr->used_ebs = cpu_to_be32(used_ebs); 846 vid_hdr->data_crc = cpu_to_be32(crc); 847 848retry: 849 pnum = ubi_wl_get_peb(ubi); 850 if (pnum < 0) { 851 ubi_free_vid_hdr(ubi, vid_hdr); 852 leb_write_unlock(ubi, vol_id, lnum); 853 up_read(&ubi->fm_eba_sem); 854 return pnum; 855 } 856 857 dbg_eba("write VID hdr and %d bytes at LEB %d:%d, PEB %d, used_ebs %d", 858 len, vol_id, lnum, pnum, used_ebs); 859 860 err = ubi_io_write_vid_hdr(ubi, pnum, vid_hdr); 861 if (err) { 862 ubi_warn(ubi, "failed to write VID header to LEB %d:%d, PEB %d", 863 vol_id, lnum, pnum); 864 up_read(&ubi->fm_eba_sem); 865 goto write_error; 866 } 867 868 err = ubi_io_write_data(ubi, buf, pnum, 0, len); 869 if (err) { 870 ubi_warn(ubi, "failed to write %d bytes of data to PEB %d", 871 len, pnum); 872 up_read(&ubi->fm_eba_sem); 873 goto write_error; 874 } 875 876 ubi_assert(vol->eba_tbl[lnum] < 0); 877 vol->eba_tbl[lnum] = pnum; 878 up_read(&ubi->fm_eba_sem); 879 880 leb_write_unlock(ubi, vol_id, lnum); 881 ubi_free_vid_hdr(ubi, vid_hdr); 882 return 0; 883 884write_error: 885 if (err != -EIO || !ubi->bad_allowed) { 886 /* 887 * This flash device does not admit of bad eraseblocks or 888 * something nasty and unexpected happened. Switch to read-only 889 * mode just in case. 890 */ 891 ubi_ro_mode(ubi); 892 leb_write_unlock(ubi, vol_id, lnum); 893 ubi_free_vid_hdr(ubi, vid_hdr); 894 return err; 895 } 896 897 err = ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 1); 898 if (err || ++tries > UBI_IO_RETRIES) { 899 ubi_ro_mode(ubi); 900 leb_write_unlock(ubi, vol_id, lnum); 901 ubi_free_vid_hdr(ubi, vid_hdr); 902 return err; 903 } 904 905 vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); 906 ubi_msg(ubi, "try another PEB"); 907 goto retry; 908} 909 910/* 911 * ubi_eba_atomic_leb_change - change logical eraseblock atomically. 912 * @ubi: UBI device description object 913 * @vol: volume description object 914 * @lnum: logical eraseblock number 915 * @buf: data to write 916 * @len: how many bytes to write 917 * 918 * This function changes the contents of a logical eraseblock atomically. @buf 919 * has to contain new logical eraseblock data, and @len - the length of the 920 * data, which has to be aligned. This function guarantees that in case of an 921 * unclean reboot the old contents is preserved. Returns zero in case of 922 * success and a negative error code in case of failure. 923 * 924 * UBI reserves one LEB for the "atomic LEB change" operation, so only one 925 * LEB change may be done at a time. This is ensured by @ubi->alc_mutex. 926 */ 927int ubi_eba_atomic_leb_change(struct ubi_device *ubi, struct ubi_volume *vol, 928 int lnum, const void *buf, int len) 929{ 930 int err, pnum, old_pnum, tries = 0, vol_id = vol->vol_id; 931 struct ubi_vid_hdr *vid_hdr; 932 uint32_t crc; 933 934 if (ubi->ro_mode) 935 return -EROFS; 936 937 if (len == 0) { 938 /* 939 * Special case when data length is zero. In this case the LEB 940 * has to be unmapped and mapped somewhere else. 941 */ 942 err = ubi_eba_unmap_leb(ubi, vol, lnum); 943 if (err) 944 return err; 945 return ubi_eba_write_leb(ubi, vol, lnum, NULL, 0, 0); 946 } 947 948 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS); 949 if (!vid_hdr) 950 return -ENOMEM; 951 952 mutex_lock(&ubi->alc_mutex); 953 err = leb_write_lock(ubi, vol_id, lnum); 954 if (err) 955 goto out_mutex; 956 957 vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); 958 vid_hdr->vol_id = cpu_to_be32(vol_id); 959 vid_hdr->lnum = cpu_to_be32(lnum); 960 vid_hdr->compat = ubi_get_compat(ubi, vol_id); 961 vid_hdr->data_pad = cpu_to_be32(vol->data_pad); 962 963 crc = crc32(UBI_CRC32_INIT, buf, len); 964 vid_hdr->vol_type = UBI_VID_DYNAMIC; 965 vid_hdr->data_size = cpu_to_be32(len); 966 vid_hdr->copy_flag = 1; 967 vid_hdr->data_crc = cpu_to_be32(crc); 968 969retry: 970 pnum = ubi_wl_get_peb(ubi); 971 if (pnum < 0) { 972 err = pnum; 973 up_read(&ubi->fm_eba_sem); 974 goto out_leb_unlock; 975 } 976 977 dbg_eba("change LEB %d:%d, PEB %d, write VID hdr to PEB %d", 978 vol_id, lnum, vol->eba_tbl[lnum], pnum); 979 980 err = ubi_io_write_vid_hdr(ubi, pnum, vid_hdr); 981 if (err) { 982 ubi_warn(ubi, "failed to write VID header to LEB %d:%d, PEB %d", 983 vol_id, lnum, pnum); 984 up_read(&ubi->fm_eba_sem); 985 goto write_error; 986 } 987 988 err = ubi_io_write_data(ubi, buf, pnum, 0, len); 989 if (err) { 990 ubi_warn(ubi, "failed to write %d bytes of data to PEB %d", 991 len, pnum); 992 up_read(&ubi->fm_eba_sem); 993 goto write_error; 994 } 995 996 old_pnum = vol->eba_tbl[lnum]; 997 vol->eba_tbl[lnum] = pnum; 998 up_read(&ubi->fm_eba_sem); 999 1000 if (old_pnum >= 0) { 1001 err = ubi_wl_put_peb(ubi, vol_id, lnum, old_pnum, 0); 1002 if (err) 1003 goto out_leb_unlock; 1004 } 1005 1006out_leb_unlock: 1007 leb_write_unlock(ubi, vol_id, lnum); 1008out_mutex: 1009 mutex_unlock(&ubi->alc_mutex); 1010 ubi_free_vid_hdr(ubi, vid_hdr); 1011 return err; 1012 1013write_error: 1014 if (err != -EIO || !ubi->bad_allowed) { 1015 /* 1016 * This flash device does not admit of bad eraseblocks or 1017 * something nasty and unexpected happened. Switch to read-only 1018 * mode just in case. 1019 */ 1020 ubi_ro_mode(ubi); 1021 goto out_leb_unlock; 1022 } 1023 1024 err = ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 1); 1025 if (err || ++tries > UBI_IO_RETRIES) { 1026 ubi_ro_mode(ubi); 1027 goto out_leb_unlock; 1028 } 1029 1030 vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); 1031 ubi_msg(ubi, "try another PEB"); 1032 goto retry; 1033} 1034 1035/** 1036 * is_error_sane - check whether a read error is sane. 1037 * @err: code of the error happened during reading 1038 * 1039 * This is a helper function for 'ubi_eba_copy_leb()' which is called when we 1040 * cannot read data from the target PEB (an error @err happened). If the error 1041 * code is sane, then we treat this error as non-fatal. Otherwise the error is 1042 * fatal and UBI will be switched to R/O mode later. 1043 * 1044 * The idea is that we try not to switch to R/O mode if the read error is 1045 * something which suggests there was a real read problem. E.g., %-EIO. Or a 1046 * memory allocation failed (-%ENOMEM). Otherwise, it is safer to switch to R/O 1047 * mode, simply because we do not know what happened at the MTD level, and we 1048 * cannot handle this. E.g., the underlying driver may have become crazy, and 1049 * it is safer to switch to R/O mode to preserve the data. 1050 * 1051 * And bear in mind, this is about reading from the target PEB, i.e. the PEB 1052 * which we have just written. 1053 */ 1054static int is_error_sane(int err) 1055{ 1056 if (err == -EIO || err == -ENOMEM || err == UBI_IO_BAD_HDR || 1057 err == UBI_IO_BAD_HDR_EBADMSG || err == -ETIMEDOUT) 1058 return 0; 1059 return 1; 1060} 1061 1062/** 1063 * ubi_eba_copy_leb - copy logical eraseblock. 1064 * @ubi: UBI device description object 1065 * @from: physical eraseblock number from where to copy 1066 * @to: physical eraseblock number where to copy 1067 * @vid_hdr: VID header of the @from physical eraseblock 1068 * 1069 * This function copies logical eraseblock from physical eraseblock @from to 1070 * physical eraseblock @to. The @vid_hdr buffer may be changed by this 1071 * function. Returns: 1072 * o %0 in case of success; 1073 * o %MOVE_CANCEL_RACE, %MOVE_TARGET_WR_ERR, %MOVE_TARGET_BITFLIPS, etc; 1074 * o a negative error code in case of failure. 1075 */ 1076int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to, 1077 struct ubi_vid_hdr *vid_hdr) 1078{ 1079 int err, vol_id, lnum, data_size, aldata_size, idx; 1080 struct ubi_volume *vol; 1081 uint32_t crc; 1082 1083 vol_id = be32_to_cpu(vid_hdr->vol_id); 1084 lnum = be32_to_cpu(vid_hdr->lnum); 1085 1086 dbg_wl("copy LEB %d:%d, PEB %d to PEB %d", vol_id, lnum, from, to); 1087 1088 if (vid_hdr->vol_type == UBI_VID_STATIC) { 1089 data_size = be32_to_cpu(vid_hdr->data_size); 1090 aldata_size = ALIGN(data_size, ubi->min_io_size); 1091 } else 1092 data_size = aldata_size = 1093 ubi->leb_size - be32_to_cpu(vid_hdr->data_pad); 1094 1095 idx = vol_id2idx(ubi, vol_id); 1096 spin_lock(&ubi->volumes_lock); 1097 /* 1098 * Note, we may race with volume deletion, which means that the volume 1099 * this logical eraseblock belongs to might be being deleted. Since the 1100 * volume deletion un-maps all the volume's logical eraseblocks, it will 1101 * be locked in 'ubi_wl_put_peb()' and wait for the WL worker to finish. 1102 */ 1103 vol = ubi->volumes[idx]; 1104 spin_unlock(&ubi->volumes_lock); 1105 if (!vol) { 1106 /* No need to do further work, cancel */ 1107 dbg_wl("volume %d is being removed, cancel", vol_id); 1108 return MOVE_CANCEL_RACE; 1109 } 1110 1111 /* 1112 * We do not want anybody to write to this logical eraseblock while we 1113 * are moving it, so lock it. 1114 * 1115 * Note, we are using non-waiting locking here, because we cannot sleep 1116 * on the LEB, since it may cause deadlocks. Indeed, imagine a task is 1117 * unmapping the LEB which is mapped to the PEB we are going to move 1118 * (@from). This task locks the LEB and goes sleep in the 1119 * 'ubi_wl_put_peb()' function on the @ubi->move_mutex. In turn, we are 1120 * holding @ubi->move_mutex and go sleep on the LEB lock. So, if the 1121 * LEB is already locked, we just do not move it and return 1122 * %MOVE_RETRY. Note, we do not return %MOVE_CANCEL_RACE here because 1123 * we do not know the reasons of the contention - it may be just a 1124 * normal I/O on this LEB, so we want to re-try. 1125 */ 1126 err = leb_write_trylock(ubi, vol_id, lnum); 1127 if (err) { 1128 dbg_wl("contention on LEB %d:%d, cancel", vol_id, lnum); 1129 return MOVE_RETRY; 1130 } 1131 1132 /* 1133 * The LEB might have been put meanwhile, and the task which put it is 1134 * probably waiting on @ubi->move_mutex. No need to continue the work, 1135 * cancel it. 1136 */ 1137 if (vol->eba_tbl[lnum] != from) { 1138 dbg_wl("LEB %d:%d is no longer mapped to PEB %d, mapped to PEB %d, cancel", 1139 vol_id, lnum, from, vol->eba_tbl[lnum]); 1140 err = MOVE_CANCEL_RACE; 1141 goto out_unlock_leb; 1142 } 1143 1144 /* 1145 * OK, now the LEB is locked and we can safely start moving it. Since 1146 * this function utilizes the @ubi->peb_buf buffer which is shared 1147 * with some other functions - we lock the buffer by taking the 1148 * @ubi->buf_mutex. 1149 */ 1150 mutex_lock(&ubi->buf_mutex); 1151 dbg_wl("read %d bytes of data", aldata_size); 1152 err = ubi_io_read_data(ubi, ubi->peb_buf, from, 0, aldata_size); 1153 if (err && err != UBI_IO_BITFLIPS) { 1154 ubi_warn(ubi, "error %d while reading data from PEB %d", 1155 err, from); 1156 err = MOVE_SOURCE_RD_ERR; 1157 goto out_unlock_buf; 1158 } 1159 1160 /* 1161 * Now we have got to calculate how much data we have to copy. In 1162 * case of a static volume it is fairly easy - the VID header contains 1163 * the data size. In case of a dynamic volume it is more difficult - we 1164 * have to read the contents, cut 0xFF bytes from the end and copy only 1165 * the first part. We must do this to avoid writing 0xFF bytes as it 1166 * may have some side-effects. And not only this. It is important not 1167 * to include those 0xFFs to CRC because later the they may be filled 1168 * by data. 1169 */ 1170 if (vid_hdr->vol_type == UBI_VID_DYNAMIC) 1171 aldata_size = data_size = 1172 ubi_calc_data_len(ubi, ubi->peb_buf, data_size); 1173 1174 cond_resched(); 1175 crc = crc32(UBI_CRC32_INIT, ubi->peb_buf, data_size); 1176 cond_resched(); 1177 1178 /* 1179 * It may turn out to be that the whole @from physical eraseblock 1180 * contains only 0xFF bytes. Then we have to only write the VID header 1181 * and do not write any data. This also means we should not set 1182 * @vid_hdr->copy_flag, @vid_hdr->data_size, and @vid_hdr->data_crc. 1183 */ 1184 if (data_size > 0) { 1185 vid_hdr->copy_flag = 1; 1186 vid_hdr->data_size = cpu_to_be32(data_size); 1187 vid_hdr->data_crc = cpu_to_be32(crc); 1188 } 1189 vid_hdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi)); 1190 1191 err = ubi_io_write_vid_hdr(ubi, to, vid_hdr); 1192 if (err) { 1193 if (err == -EIO) 1194 err = MOVE_TARGET_WR_ERR; 1195 goto out_unlock_buf; 1196 } 1197 1198 cond_resched(); 1199 1200 /* Read the VID header back and check if it was written correctly */ 1201 err = ubi_io_read_vid_hdr(ubi, to, vid_hdr, 1); 1202 if (err) { 1203 if (err != UBI_IO_BITFLIPS) { 1204 ubi_warn(ubi, "error %d while reading VID header back from PEB %d", 1205 err, to); 1206 if (is_error_sane(err)) 1207 err = MOVE_TARGET_RD_ERR; 1208 } else 1209 err = MOVE_TARGET_BITFLIPS; 1210 goto out_unlock_buf; 1211 } 1212 1213 if (data_size > 0) { 1214 err = ubi_io_write_data(ubi, ubi->peb_buf, to, 0, aldata_size); 1215 if (err) { 1216 if (err == -EIO) 1217 err = MOVE_TARGET_WR_ERR; 1218 goto out_unlock_buf; 1219 } 1220 1221 cond_resched(); 1222 1223 /* 1224 * We've written the data and are going to read it back to make 1225 * sure it was written correctly. 1226 */ 1227 memset(ubi->peb_buf, 0xFF, aldata_size); 1228 err = ubi_io_read_data(ubi, ubi->peb_buf, to, 0, aldata_size); 1229 if (err) { 1230 if (err != UBI_IO_BITFLIPS) { 1231 ubi_warn(ubi, "error %d while reading data back from PEB %d", 1232 err, to); 1233 if (is_error_sane(err)) 1234 err = MOVE_TARGET_RD_ERR; 1235 } else 1236 err = MOVE_TARGET_BITFLIPS; 1237 goto out_unlock_buf; 1238 } 1239 1240 cond_resched(); 1241 1242 if (crc != crc32(UBI_CRC32_INIT, ubi->peb_buf, data_size)) { 1243 ubi_warn(ubi, "read data back from PEB %d and it is different", 1244 to); 1245 err = -EINVAL; 1246 goto out_unlock_buf; 1247 } 1248 } 1249 1250 ubi_assert(vol->eba_tbl[lnum] == from); 1251 down_read(&ubi->fm_eba_sem); 1252 vol->eba_tbl[lnum] = to; 1253 up_read(&ubi->fm_eba_sem); 1254 1255out_unlock_buf: 1256 mutex_unlock(&ubi->buf_mutex); 1257out_unlock_leb: 1258 leb_write_unlock(ubi, vol_id, lnum); 1259 return err; 1260} 1261 1262/** 1263 * print_rsvd_warning - warn about not having enough reserved PEBs. 1264 * @ubi: UBI device description object 1265 * 1266 * This is a helper function for 'ubi_eba_init()' which is called when UBI 1267 * cannot reserve enough PEBs for bad block handling. This function makes a 1268 * decision whether we have to print a warning or not. The algorithm is as 1269 * follows: 1270 * o if this is a new UBI image, then just print the warning 1271 * o if this is an UBI image which has already been used for some time, print 1272 * a warning only if we can reserve less than 10% of the expected amount of 1273 * the reserved PEB. 1274 * 1275 * The idea is that when UBI is used, PEBs become bad, and the reserved pool 1276 * of PEBs becomes smaller, which is normal and we do not want to scare users 1277 * with a warning every time they attach the MTD device. This was an issue 1278 * reported by real users. 1279 */ 1280static void print_rsvd_warning(struct ubi_device *ubi, 1281 struct ubi_attach_info *ai) 1282{ 1283 /* 1284 * The 1 << 18 (256KiB) number is picked randomly, just a reasonably 1285 * large number to distinguish between newly flashed and used images. 1286 */ 1287 if (ai->max_sqnum > (1 << 18)) { 1288 int min = ubi->beb_rsvd_level / 10; 1289 1290 if (!min) 1291 min = 1; 1292 if (ubi->beb_rsvd_pebs > min) 1293 return; 1294 } 1295 1296 ubi_warn(ubi, "cannot reserve enough PEBs for bad PEB handling, reserved %d, need %d", 1297 ubi->beb_rsvd_pebs, ubi->beb_rsvd_level); 1298 if (ubi->corr_peb_count) 1299 ubi_warn(ubi, "%d PEBs are corrupted and not used", 1300 ubi->corr_peb_count); 1301} 1302 1303/** 1304 * self_check_eba - run a self check on the EBA table constructed by fastmap. 1305 * @ubi: UBI device description object 1306 * @ai_fastmap: UBI attach info object created by fastmap 1307 * @ai_scan: UBI attach info object created by scanning 1308 * 1309 * Returns < 0 in case of an internal error, 0 otherwise. 1310 * If a bad EBA table entry was found it will be printed out and 1311 * ubi_assert() triggers. 1312 */ 1313int self_check_eba(struct ubi_device *ubi, struct ubi_attach_info *ai_fastmap, 1314 struct ubi_attach_info *ai_scan) 1315{ 1316 int i, j, num_volumes, ret = 0; 1317 int **scan_eba, **fm_eba; 1318 struct ubi_ainf_volume *av; 1319 struct ubi_volume *vol; 1320 struct ubi_ainf_peb *aeb; 1321 struct rb_node *rb; 1322 1323 num_volumes = ubi->vtbl_slots + UBI_INT_VOL_COUNT; 1324 1325 scan_eba = kmalloc(sizeof(*scan_eba) * num_volumes, GFP_KERNEL); 1326 if (!scan_eba) 1327 return -ENOMEM; 1328 1329 fm_eba = kmalloc(sizeof(*fm_eba) * num_volumes, GFP_KERNEL); 1330 if (!fm_eba) { 1331 kfree(scan_eba); 1332 return -ENOMEM; 1333 } 1334 1335 for (i = 0; i < num_volumes; i++) { 1336 vol = ubi->volumes[i]; 1337 if (!vol) 1338 continue; 1339 1340 scan_eba[i] = kmalloc(vol->reserved_pebs * sizeof(**scan_eba), 1341 GFP_KERNEL); 1342 if (!scan_eba[i]) { 1343 ret = -ENOMEM; 1344 goto out_free; 1345 } 1346 1347 fm_eba[i] = kmalloc(vol->reserved_pebs * sizeof(**fm_eba), 1348 GFP_KERNEL); 1349 if (!fm_eba[i]) { 1350 ret = -ENOMEM; 1351 goto out_free; 1352 } 1353 1354 for (j = 0; j < vol->reserved_pebs; j++) 1355 scan_eba[i][j] = fm_eba[i][j] = UBI_LEB_UNMAPPED; 1356 1357 av = ubi_find_av(ai_scan, idx2vol_id(ubi, i)); 1358 if (!av) 1359 continue; 1360 1361 ubi_rb_for_each_entry(rb, aeb, &av->root, u.rb) 1362 scan_eba[i][aeb->lnum] = aeb->pnum; 1363 1364 av = ubi_find_av(ai_fastmap, idx2vol_id(ubi, i)); 1365 if (!av) 1366 continue; 1367 1368 ubi_rb_for_each_entry(rb, aeb, &av->root, u.rb) 1369 fm_eba[i][aeb->lnum] = aeb->pnum; 1370 1371 for (j = 0; j < vol->reserved_pebs; j++) { 1372 if (scan_eba[i][j] != fm_eba[i][j]) { 1373 if (scan_eba[i][j] == UBI_LEB_UNMAPPED || 1374 fm_eba[i][j] == UBI_LEB_UNMAPPED) 1375 continue; 1376 1377 ubi_err(ubi, "LEB:%i:%i is PEB:%i instead of %i!", 1378 vol->vol_id, i, fm_eba[i][j], 1379 scan_eba[i][j]); 1380 ubi_assert(0); 1381 } 1382 } 1383 } 1384 1385out_free: 1386 for (i = 0; i < num_volumes; i++) { 1387 if (!ubi->volumes[i]) 1388 continue; 1389 1390 kfree(scan_eba[i]); 1391 kfree(fm_eba[i]); 1392 } 1393 1394 kfree(scan_eba); 1395 kfree(fm_eba); 1396 return ret; 1397} 1398 1399/** 1400 * ubi_eba_init - initialize the EBA sub-system using attaching information. 1401 * @ubi: UBI device description object 1402 * @ai: attaching information 1403 * 1404 * This function returns zero in case of success and a negative error code in 1405 * case of failure. 1406 */ 1407int ubi_eba_init(struct ubi_device *ubi, struct ubi_attach_info *ai) 1408{ 1409 int i, j, err, num_volumes; 1410 struct ubi_ainf_volume *av; 1411 struct ubi_volume *vol; 1412 struct ubi_ainf_peb *aeb; 1413 struct rb_node *rb; 1414 1415 dbg_eba("initialize EBA sub-system"); 1416 1417 spin_lock_init(&ubi->ltree_lock); 1418 mutex_init(&ubi->alc_mutex); 1419 ubi->ltree = RB_ROOT; 1420 1421 ubi->global_sqnum = ai->max_sqnum + 1; 1422 num_volumes = ubi->vtbl_slots + UBI_INT_VOL_COUNT; 1423 1424 for (i = 0; i < num_volumes; i++) { 1425 vol = ubi->volumes[i]; 1426 if (!vol) 1427 continue; 1428 1429 cond_resched(); 1430 1431 vol->eba_tbl = kmalloc(vol->reserved_pebs * sizeof(int), 1432 GFP_KERNEL); 1433 if (!vol->eba_tbl) { 1434 err = -ENOMEM; 1435 goto out_free; 1436 } 1437 1438 for (j = 0; j < vol->reserved_pebs; j++) 1439 vol->eba_tbl[j] = UBI_LEB_UNMAPPED; 1440 1441 av = ubi_find_av(ai, idx2vol_id(ubi, i)); 1442 if (!av) 1443 continue; 1444 1445 ubi_rb_for_each_entry(rb, aeb, &av->root, u.rb) { 1446 if (aeb->lnum >= vol->reserved_pebs) 1447 /* 1448 * This may happen in case of an unclean reboot 1449 * during re-size. 1450 */ 1451 ubi_move_aeb_to_list(av, aeb, &ai->erase); 1452 else 1453 vol->eba_tbl[aeb->lnum] = aeb->pnum; 1454 } 1455 } 1456 1457 if (ubi->avail_pebs < EBA_RESERVED_PEBS) { 1458 ubi_err(ubi, "no enough physical eraseblocks (%d, need %d)", 1459 ubi->avail_pebs, EBA_RESERVED_PEBS); 1460 if (ubi->corr_peb_count) 1461 ubi_err(ubi, "%d PEBs are corrupted and not used", 1462 ubi->corr_peb_count); 1463 err = -ENOSPC; 1464 goto out_free; 1465 } 1466 ubi->avail_pebs -= EBA_RESERVED_PEBS; 1467 ubi->rsvd_pebs += EBA_RESERVED_PEBS; 1468 1469 if (ubi->bad_allowed) { 1470 ubi_calculate_reserved(ubi); 1471 1472 if (ubi->avail_pebs < ubi->beb_rsvd_level) { 1473 /* No enough free physical eraseblocks */ 1474 ubi->beb_rsvd_pebs = ubi->avail_pebs; 1475 print_rsvd_warning(ubi, ai); 1476 } else 1477 ubi->beb_rsvd_pebs = ubi->beb_rsvd_level; 1478 1479 ubi->avail_pebs -= ubi->beb_rsvd_pebs; 1480 ubi->rsvd_pebs += ubi->beb_rsvd_pebs; 1481 } 1482 1483 dbg_eba("EBA sub-system is initialized"); 1484 return 0; 1485 1486out_free: 1487 for (i = 0; i < num_volumes; i++) { 1488 if (!ubi->volumes[i]) 1489 continue; 1490 kfree(ubi->volumes[i]->eba_tbl); 1491 ubi->volumes[i]->eba_tbl = NULL; 1492 } 1493 return err; 1494} 1495