1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright © 2009 - Maxim Levitsky 4 * SmartMedia/xD translation layer 5 */ 6 7 #include <linux/kernel.h> 8 #include <linux/module.h> 9 #include <linux/random.h> 10 #include <linux/hdreg.h> 11 #include <linux/kthread.h> 12 #include <linux/freezer.h> 13 #include <linux/sysfs.h> 14 #include <linux/bitops.h> 15 #include <linux/slab.h> 16 #include <linux/mtd/nand-ecc-sw-hamming.h> 17 #include "nand/raw/sm_common.h" 18 #include "sm_ftl.h" 19 20 21 22 static struct workqueue_struct *cache_flush_workqueue; 23 24 static int cache_timeout = 1000; 25 module_param(cache_timeout, int, S_IRUGO); 26 MODULE_PARM_DESC(cache_timeout, 27 "Timeout (in ms) for cache flush (1000 ms default"); 28 29 static int debug; 30 module_param(debug, int, S_IRUGO | S_IWUSR); 31 MODULE_PARM_DESC(debug, "Debug level (0-2)"); 32 33 34 /* ------------------- sysfs attributes ---------------------------------- */ 35 struct sm_sysfs_attribute { 36 struct device_attribute dev_attr; 37 char *data; 38 int len; 39 }; 40 41 static ssize_t sm_attr_show(struct device *dev, struct device_attribute *attr, 42 char *buf) 43 { 44 struct sm_sysfs_attribute *sm_attr = 45 container_of(attr, struct sm_sysfs_attribute, dev_attr); 46 47 strncpy(buf, sm_attr->data, sm_attr->len); 48 return sm_attr->len; 49 } 50 51 52 #define NUM_ATTRIBUTES 1 53 #define SM_CIS_VENDOR_OFFSET 0x59 54 static struct attribute_group *sm_create_sysfs_attributes(struct sm_ftl *ftl) 55 { 56 struct attribute_group *attr_group; 57 struct attribute **attributes; 58 struct sm_sysfs_attribute *vendor_attribute; 59 char *vendor; 60 61 vendor = kstrndup(ftl->cis_buffer + SM_CIS_VENDOR_OFFSET, 62 SM_SMALL_PAGE - SM_CIS_VENDOR_OFFSET, GFP_KERNEL); 63 if (!vendor) 64 goto error1; 65 66 /* Initialize sysfs attributes */ 67 vendor_attribute = 68 kzalloc(sizeof(struct sm_sysfs_attribute), GFP_KERNEL); 69 if (!vendor_attribute) 70 goto error2; 71 72 sysfs_attr_init(&vendor_attribute->dev_attr.attr); 73 74 vendor_attribute->data = vendor; 75 vendor_attribute->len = strlen(vendor); 76 vendor_attribute->dev_attr.attr.name = "vendor"; 77 vendor_attribute->dev_attr.attr.mode = S_IRUGO; 78 vendor_attribute->dev_attr.show = sm_attr_show; 79 80 81 /* Create array of pointers to the attributes */ 82 attributes = kcalloc(NUM_ATTRIBUTES + 1, sizeof(struct attribute *), 83 GFP_KERNEL); 84 if (!attributes) 85 goto error3; 86 attributes[0] = &vendor_attribute->dev_attr.attr; 87 88 /* Finally create the attribute group */ 89 attr_group = kzalloc(sizeof(struct attribute_group), GFP_KERNEL); 90 if (!attr_group) 91 goto error4; 92 attr_group->attrs = attributes; 93 return attr_group; 94 error4: 95 kfree(attributes); 96 error3: 97 kfree(vendor_attribute); 98 error2: 99 kfree(vendor); 100 error1: 101 return NULL; 102 } 103 104 static void sm_delete_sysfs_attributes(struct sm_ftl *ftl) 105 { 106 struct attribute **attributes = ftl->disk_attributes->attrs; 107 int i; 108 109 for (i = 0; attributes[i] ; i++) { 110 111 struct device_attribute *dev_attr = container_of(attributes[i], 112 struct device_attribute, attr); 113 114 struct sm_sysfs_attribute *sm_attr = 115 container_of(dev_attr, 116 struct sm_sysfs_attribute, dev_attr); 117 118 kfree(sm_attr->data); 119 kfree(sm_attr); 120 } 121 122 kfree(ftl->disk_attributes->attrs); 123 kfree(ftl->disk_attributes); 124 } 125 126 127 /* ----------------------- oob helpers -------------------------------------- */ 128 129 static int sm_get_lba(uint8_t *lba) 130 { 131 /* check fixed bits */ 132 if ((lba[0] & 0xF8) != 0x10) 133 return -2; 134 135 /* check parity - endianness doesn't matter */ 136 if (hweight16(*(uint16_t *)lba) & 1) 137 return -2; 138 139 return (lba[1] >> 1) | ((lba[0] & 0x07) << 7); 140 } 141 142 143 /* 144 * Read LBA associated with block 145 * returns -1, if block is erased 146 * returns -2 if error happens 147 */ 148 static int sm_read_lba(struct sm_oob *oob) 149 { 150 static const uint32_t erased_pattern[4] = { 151 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF }; 152 153 uint16_t lba_test; 154 int lba; 155 156 /* First test for erased block */ 157 if (!memcmp(oob, erased_pattern, SM_OOB_SIZE)) 158 return -1; 159 160 /* Now check is both copies of the LBA differ too much */ 161 lba_test = *(uint16_t *)oob->lba_copy1 ^ *(uint16_t*)oob->lba_copy2; 162 if (lba_test && !is_power_of_2(lba_test)) 163 return -2; 164 165 /* And read it */ 166 lba = sm_get_lba(oob->lba_copy1); 167 168 if (lba == -2) 169 lba = sm_get_lba(oob->lba_copy2); 170 171 return lba; 172 } 173 174 static void sm_write_lba(struct sm_oob *oob, uint16_t lba) 175 { 176 uint8_t tmp[2]; 177 178 WARN_ON(lba >= 1000); 179 180 tmp[0] = 0x10 | ((lba >> 7) & 0x07); 181 tmp[1] = (lba << 1) & 0xFF; 182 183 if (hweight16(*(uint16_t *)tmp) & 0x01) 184 tmp[1] |= 1; 185 186 oob->lba_copy1[0] = oob->lba_copy2[0] = tmp[0]; 187 oob->lba_copy1[1] = oob->lba_copy2[1] = tmp[1]; 188 } 189 190 191 /* Make offset from parts */ 192 static loff_t sm_mkoffset(struct sm_ftl *ftl, int zone, int block, int boffset) 193 { 194 WARN_ON(boffset & (SM_SECTOR_SIZE - 1)); 195 WARN_ON(zone < 0 || zone >= ftl->zone_count); 196 WARN_ON(block >= ftl->zone_size); 197 WARN_ON(boffset >= ftl->block_size); 198 199 if (block == -1) 200 return -1; 201 202 return (zone * SM_MAX_ZONE_SIZE + block) * ftl->block_size + boffset; 203 } 204 205 /* Breaks offset into parts */ 206 static void sm_break_offset(struct sm_ftl *ftl, loff_t loffset, 207 int *zone, int *block, int *boffset) 208 { 209 u64 offset = loffset; 210 *boffset = do_div(offset, ftl->block_size); 211 *block = do_div(offset, ftl->max_lba); 212 *zone = offset >= ftl->zone_count ? -1 : offset; 213 } 214 215 /* ---------------------- low level IO ------------------------------------- */ 216 217 static int sm_correct_sector(uint8_t *buffer, struct sm_oob *oob) 218 { 219 bool sm_order = IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC); 220 uint8_t ecc[3]; 221 222 ecc_sw_hamming_calculate(buffer, SM_SMALL_PAGE, ecc, sm_order); 223 if (ecc_sw_hamming_correct(buffer, ecc, oob->ecc1, SM_SMALL_PAGE, 224 sm_order) < 0) 225 return -EIO; 226 227 buffer += SM_SMALL_PAGE; 228 229 ecc_sw_hamming_calculate(buffer, SM_SMALL_PAGE, ecc, sm_order); 230 if (ecc_sw_hamming_correct(buffer, ecc, oob->ecc2, SM_SMALL_PAGE, 231 sm_order) < 0) 232 return -EIO; 233 return 0; 234 } 235 236 /* Reads a sector + oob*/ 237 static int sm_read_sector(struct sm_ftl *ftl, 238 int zone, int block, int boffset, 239 uint8_t *buffer, struct sm_oob *oob) 240 { 241 struct mtd_info *mtd = ftl->trans->mtd; 242 struct mtd_oob_ops ops; 243 struct sm_oob tmp_oob; 244 int ret = -EIO; 245 int try = 0; 246 247 /* FTL can contain -1 entries that are by default filled with bits */ 248 if (block == -1) { 249 if (buffer) 250 memset(buffer, 0xFF, SM_SECTOR_SIZE); 251 return 0; 252 } 253 254 /* User might not need the oob, but we do for data verification */ 255 if (!oob) 256 oob = &tmp_oob; 257 258 ops.mode = ftl->smallpagenand ? MTD_OPS_RAW : MTD_OPS_PLACE_OOB; 259 ops.ooboffs = 0; 260 ops.ooblen = SM_OOB_SIZE; 261 ops.oobbuf = (void *)oob; 262 ops.len = SM_SECTOR_SIZE; 263 ops.datbuf = buffer; 264 265 again: 266 if (try++) { 267 /* Avoid infinite recursion on CIS reads, sm_recheck_media 268 won't help anyway */ 269 if (zone == 0 && block == ftl->cis_block && boffset == 270 ftl->cis_boffset) 271 return ret; 272 273 /* Test if media is stable */ 274 if (try == 3 || sm_recheck_media(ftl)) 275 return ret; 276 } 277 278 /* Unfortunately, oob read will _always_ succeed, 279 despite card removal..... */ 280 ret = mtd_read_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops); 281 282 /* Test for unknown errors */ 283 if (ret != 0 && !mtd_is_bitflip_or_eccerr(ret)) { 284 dbg("read of block %d at zone %d, failed due to error (%d)", 285 block, zone, ret); 286 goto again; 287 } 288 289 /* Do a basic test on the oob, to guard against returned garbage */ 290 if (oob->reserved != 0xFFFFFFFF && !is_power_of_2(~oob->reserved)) 291 goto again; 292 293 /* This should never happen, unless there is a bug in the mtd driver */ 294 WARN_ON(ops.oobretlen != SM_OOB_SIZE); 295 WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE); 296 297 if (!buffer) 298 return 0; 299 300 /* Test if sector marked as bad */ 301 if (!sm_sector_valid(oob)) { 302 dbg("read of block %d at zone %d, failed because it is marked" 303 " as bad" , block, zone); 304 goto again; 305 } 306 307 /* Test ECC*/ 308 if (mtd_is_eccerr(ret) || 309 (ftl->smallpagenand && sm_correct_sector(buffer, oob))) { 310 311 dbg("read of block %d at zone %d, failed due to ECC error", 312 block, zone); 313 goto again; 314 } 315 316 return 0; 317 } 318 319 /* Writes a sector to media */ 320 static int sm_write_sector(struct sm_ftl *ftl, 321 int zone, int block, int boffset, 322 uint8_t *buffer, struct sm_oob *oob) 323 { 324 struct mtd_oob_ops ops; 325 struct mtd_info *mtd = ftl->trans->mtd; 326 int ret; 327 328 BUG_ON(ftl->readonly); 329 330 if (zone == 0 && (block == ftl->cis_block || block == 0)) { 331 dbg("attempted to write the CIS!"); 332 return -EIO; 333 } 334 335 if (ftl->unstable) 336 return -EIO; 337 338 ops.mode = ftl->smallpagenand ? MTD_OPS_RAW : MTD_OPS_PLACE_OOB; 339 ops.len = SM_SECTOR_SIZE; 340 ops.datbuf = buffer; 341 ops.ooboffs = 0; 342 ops.ooblen = SM_OOB_SIZE; 343 ops.oobbuf = (void *)oob; 344 345 ret = mtd_write_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops); 346 347 /* Now we assume that hardware will catch write bitflip errors */ 348 349 if (ret) { 350 dbg("write to block %d at zone %d, failed with error %d", 351 block, zone, ret); 352 353 sm_recheck_media(ftl); 354 return ret; 355 } 356 357 /* This should never happen, unless there is a bug in the driver */ 358 WARN_ON(ops.oobretlen != SM_OOB_SIZE); 359 WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE); 360 361 return 0; 362 } 363 364 /* ------------------------ block IO ------------------------------------- */ 365 366 /* Write a block using data and lba, and invalid sector bitmap */ 367 static int sm_write_block(struct sm_ftl *ftl, uint8_t *buf, 368 int zone, int block, int lba, 369 unsigned long invalid_bitmap) 370 { 371 bool sm_order = IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC); 372 struct sm_oob oob; 373 int boffset; 374 int retry = 0; 375 376 /* Initialize the oob with requested values */ 377 memset(&oob, 0xFF, SM_OOB_SIZE); 378 sm_write_lba(&oob, lba); 379 restart: 380 if (ftl->unstable) 381 return -EIO; 382 383 for (boffset = 0; boffset < ftl->block_size; 384 boffset += SM_SECTOR_SIZE) { 385 386 oob.data_status = 0xFF; 387 388 if (test_bit(boffset / SM_SECTOR_SIZE, &invalid_bitmap)) { 389 390 sm_printk("sector %d of block at LBA %d of zone %d" 391 " couldn't be read, marking it as invalid", 392 boffset / SM_SECTOR_SIZE, lba, zone); 393 394 oob.data_status = 0; 395 } 396 397 if (ftl->smallpagenand) { 398 ecc_sw_hamming_calculate(buf + boffset, 399 SM_SMALL_PAGE, oob.ecc1, 400 sm_order); 401 402 ecc_sw_hamming_calculate(buf + boffset + SM_SMALL_PAGE, 403 SM_SMALL_PAGE, oob.ecc2, 404 sm_order); 405 } 406 if (!sm_write_sector(ftl, zone, block, boffset, 407 buf + boffset, &oob)) 408 continue; 409 410 if (!retry) { 411 412 /* If write fails. try to erase the block */ 413 /* This is safe, because we never write in blocks 414 that contain valuable data. 415 This is intended to repair block that are marked 416 as erased, but that isn't fully erased*/ 417 418 if (sm_erase_block(ftl, zone, block, 0)) 419 return -EIO; 420 421 retry = 1; 422 goto restart; 423 } else { 424 sm_mark_block_bad(ftl, zone, block); 425 return -EIO; 426 } 427 } 428 return 0; 429 } 430 431 432 /* Mark whole block at offset 'offs' as bad. */ 433 static void sm_mark_block_bad(struct sm_ftl *ftl, int zone, int block) 434 { 435 struct sm_oob oob; 436 int boffset; 437 438 memset(&oob, 0xFF, SM_OOB_SIZE); 439 oob.block_status = 0xF0; 440 441 if (ftl->unstable) 442 return; 443 444 if (sm_recheck_media(ftl)) 445 return; 446 447 sm_printk("marking block %d of zone %d as bad", block, zone); 448 449 /* We aren't checking the return value, because we don't care */ 450 /* This also fails on fake xD cards, but I guess these won't expose 451 any bad blocks till fail completely */ 452 for (boffset = 0; boffset < ftl->block_size; boffset += SM_SECTOR_SIZE) 453 sm_write_sector(ftl, zone, block, boffset, NULL, &oob); 454 } 455 456 /* 457 * Erase a block within a zone 458 * If erase succeeds, it updates free block fifo, otherwise marks block as bad 459 */ 460 static int sm_erase_block(struct sm_ftl *ftl, int zone_num, uint16_t block, 461 int put_free) 462 { 463 struct ftl_zone *zone = &ftl->zones[zone_num]; 464 struct mtd_info *mtd = ftl->trans->mtd; 465 struct erase_info erase; 466 467 erase.addr = sm_mkoffset(ftl, zone_num, block, 0); 468 erase.len = ftl->block_size; 469 470 if (ftl->unstable) 471 return -EIO; 472 473 BUG_ON(ftl->readonly); 474 475 if (zone_num == 0 && (block == ftl->cis_block || block == 0)) { 476 sm_printk("attempted to erase the CIS!"); 477 return -EIO; 478 } 479 480 if (mtd_erase(mtd, &erase)) { 481 sm_printk("erase of block %d in zone %d failed", 482 block, zone_num); 483 goto error; 484 } 485 486 if (put_free) 487 kfifo_in(&zone->free_sectors, 488 (const unsigned char *)&block, sizeof(block)); 489 490 return 0; 491 error: 492 sm_mark_block_bad(ftl, zone_num, block); 493 return -EIO; 494 } 495 496 /* Thoroughly test that block is valid. */ 497 static int sm_check_block(struct sm_ftl *ftl, int zone, int block) 498 { 499 int boffset; 500 struct sm_oob oob; 501 int lbas[] = { -3, 0, 0, 0 }; 502 int i = 0; 503 int test_lba; 504 505 506 /* First just check that block doesn't look fishy */ 507 /* Only blocks that are valid or are sliced in two parts, are 508 accepted */ 509 for (boffset = 0; boffset < ftl->block_size; 510 boffset += SM_SECTOR_SIZE) { 511 512 /* This shouldn't happen anyway */ 513 if (sm_read_sector(ftl, zone, block, boffset, NULL, &oob)) 514 return -2; 515 516 test_lba = sm_read_lba(&oob); 517 518 if (lbas[i] != test_lba) 519 lbas[++i] = test_lba; 520 521 /* If we found three different LBAs, something is fishy */ 522 if (i == 3) 523 return -EIO; 524 } 525 526 /* If the block is sliced (partially erased usually) erase it */ 527 if (i == 2) { 528 sm_erase_block(ftl, zone, block, 1); 529 return 1; 530 } 531 532 return 0; 533 } 534 535 /* ----------------- media scanning --------------------------------- */ 536 static const struct chs_entry chs_table[] = { 537 { 1, 125, 4, 4 }, 538 { 2, 125, 4, 8 }, 539 { 4, 250, 4, 8 }, 540 { 8, 250, 4, 16 }, 541 { 16, 500, 4, 16 }, 542 { 32, 500, 8, 16 }, 543 { 64, 500, 8, 32 }, 544 { 128, 500, 16, 32 }, 545 { 256, 1000, 16, 32 }, 546 { 512, 1015, 32, 63 }, 547 { 1024, 985, 33, 63 }, 548 { 2048, 985, 33, 63 }, 549 { 0 }, 550 }; 551 552 553 static const uint8_t cis_signature[] = { 554 0x01, 0x03, 0xD9, 0x01, 0xFF, 0x18, 0x02, 0xDF, 0x01, 0x20 555 }; 556 /* Find out media parameters. 557 * This ideally has to be based on nand id, but for now device size is enough */ 558 static int sm_get_media_info(struct sm_ftl *ftl, struct mtd_info *mtd) 559 { 560 int i; 561 int size_in_megs = mtd->size / (1024 * 1024); 562 563 ftl->readonly = mtd->type == MTD_ROM; 564 565 /* Manual settings for very old devices */ 566 ftl->zone_count = 1; 567 ftl->smallpagenand = 0; 568 569 switch (size_in_megs) { 570 case 1: 571 /* 1 MiB flash/rom SmartMedia card (256 byte pages)*/ 572 ftl->zone_size = 256; 573 ftl->max_lba = 250; 574 ftl->block_size = 8 * SM_SECTOR_SIZE; 575 ftl->smallpagenand = 1; 576 577 break; 578 case 2: 579 /* 2 MiB flash SmartMedia (256 byte pages)*/ 580 if (mtd->writesize == SM_SMALL_PAGE) { 581 ftl->zone_size = 512; 582 ftl->max_lba = 500; 583 ftl->block_size = 8 * SM_SECTOR_SIZE; 584 ftl->smallpagenand = 1; 585 /* 2 MiB rom SmartMedia */ 586 } else { 587 588 if (!ftl->readonly) 589 return -ENODEV; 590 591 ftl->zone_size = 256; 592 ftl->max_lba = 250; 593 ftl->block_size = 16 * SM_SECTOR_SIZE; 594 } 595 break; 596 case 4: 597 /* 4 MiB flash/rom SmartMedia device */ 598 ftl->zone_size = 512; 599 ftl->max_lba = 500; 600 ftl->block_size = 16 * SM_SECTOR_SIZE; 601 break; 602 case 8: 603 /* 8 MiB flash/rom SmartMedia device */ 604 ftl->zone_size = 1024; 605 ftl->max_lba = 1000; 606 ftl->block_size = 16 * SM_SECTOR_SIZE; 607 } 608 609 /* Minimum xD size is 16MiB. Also, all xD cards have standard zone 610 sizes. SmartMedia cards exist up to 128 MiB and have same layout*/ 611 if (size_in_megs >= 16) { 612 ftl->zone_count = size_in_megs / 16; 613 ftl->zone_size = 1024; 614 ftl->max_lba = 1000; 615 ftl->block_size = 32 * SM_SECTOR_SIZE; 616 } 617 618 /* Test for proper write,erase and oob sizes */ 619 if (mtd->erasesize > ftl->block_size) 620 return -ENODEV; 621 622 if (mtd->writesize > SM_SECTOR_SIZE) 623 return -ENODEV; 624 625 if (ftl->smallpagenand && mtd->oobsize < SM_SMALL_OOB_SIZE) 626 return -ENODEV; 627 628 if (!ftl->smallpagenand && mtd->oobsize < SM_OOB_SIZE) 629 return -ENODEV; 630 631 /* We use OOB */ 632 if (!mtd_has_oob(mtd)) 633 return -ENODEV; 634 635 /* Find geometry information */ 636 for (i = 0 ; i < ARRAY_SIZE(chs_table) ; i++) { 637 if (chs_table[i].size == size_in_megs) { 638 ftl->cylinders = chs_table[i].cyl; 639 ftl->heads = chs_table[i].head; 640 ftl->sectors = chs_table[i].sec; 641 return 0; 642 } 643 } 644 645 sm_printk("media has unknown size : %dMiB", size_in_megs); 646 ftl->cylinders = 985; 647 ftl->heads = 33; 648 ftl->sectors = 63; 649 return 0; 650 } 651 652 /* Validate the CIS */ 653 static int sm_read_cis(struct sm_ftl *ftl) 654 { 655 struct sm_oob oob; 656 657 if (sm_read_sector(ftl, 658 0, ftl->cis_block, ftl->cis_boffset, ftl->cis_buffer, &oob)) 659 return -EIO; 660 661 if (!sm_sector_valid(&oob) || !sm_block_valid(&oob)) 662 return -EIO; 663 664 if (!memcmp(ftl->cis_buffer + ftl->cis_page_offset, 665 cis_signature, sizeof(cis_signature))) { 666 return 0; 667 } 668 669 return -EIO; 670 } 671 672 /* Scan the media for the CIS */ 673 static int sm_find_cis(struct sm_ftl *ftl) 674 { 675 struct sm_oob oob; 676 int block, boffset; 677 int block_found = 0; 678 int cis_found = 0; 679 680 /* Search for first valid block */ 681 for (block = 0 ; block < ftl->zone_size - ftl->max_lba ; block++) { 682 683 if (sm_read_sector(ftl, 0, block, 0, NULL, &oob)) 684 continue; 685 686 if (!sm_block_valid(&oob)) 687 continue; 688 block_found = 1; 689 break; 690 } 691 692 if (!block_found) 693 return -EIO; 694 695 /* Search for first valid sector in this block */ 696 for (boffset = 0 ; boffset < ftl->block_size; 697 boffset += SM_SECTOR_SIZE) { 698 699 if (sm_read_sector(ftl, 0, block, boffset, NULL, &oob)) 700 continue; 701 702 if (!sm_sector_valid(&oob)) 703 continue; 704 break; 705 } 706 707 if (boffset == ftl->block_size) 708 return -EIO; 709 710 ftl->cis_block = block; 711 ftl->cis_boffset = boffset; 712 ftl->cis_page_offset = 0; 713 714 cis_found = !sm_read_cis(ftl); 715 716 if (!cis_found) { 717 ftl->cis_page_offset = SM_SMALL_PAGE; 718 cis_found = !sm_read_cis(ftl); 719 } 720 721 if (cis_found) { 722 dbg("CIS block found at offset %x", 723 block * ftl->block_size + 724 boffset + ftl->cis_page_offset); 725 return 0; 726 } 727 return -EIO; 728 } 729 730 /* Basic test to determine if underlying mtd device if functional */ 731 static int sm_recheck_media(struct sm_ftl *ftl) 732 { 733 if (sm_read_cis(ftl)) { 734 735 if (!ftl->unstable) { 736 sm_printk("media unstable, not allowing writes"); 737 ftl->unstable = 1; 738 } 739 return -EIO; 740 } 741 return 0; 742 } 743 744 /* Initialize a FTL zone */ 745 static int sm_init_zone(struct sm_ftl *ftl, int zone_num) 746 { 747 struct ftl_zone *zone = &ftl->zones[zone_num]; 748 struct sm_oob oob; 749 uint16_t block; 750 int lba; 751 int i = 0; 752 int len; 753 754 dbg("initializing zone %d", zone_num); 755 756 /* Allocate memory for FTL table */ 757 zone->lba_to_phys_table = kmalloc_array(ftl->max_lba, 2, GFP_KERNEL); 758 759 if (!zone->lba_to_phys_table) 760 return -ENOMEM; 761 memset(zone->lba_to_phys_table, -1, ftl->max_lba * 2); 762 763 764 /* Allocate memory for free sectors FIFO */ 765 if (kfifo_alloc(&zone->free_sectors, ftl->zone_size * 2, GFP_KERNEL)) { 766 kfree(zone->lba_to_phys_table); 767 return -ENOMEM; 768 } 769 770 /* Now scan the zone */ 771 for (block = 0 ; block < ftl->zone_size ; block++) { 772 773 /* Skip blocks till the CIS (including) */ 774 if (zone_num == 0 && block <= ftl->cis_block) 775 continue; 776 777 /* Read the oob of first sector */ 778 if (sm_read_sector(ftl, zone_num, block, 0, NULL, &oob)) { 779 kfifo_free(&zone->free_sectors); 780 kfree(zone->lba_to_phys_table); 781 return -EIO; 782 } 783 784 /* Test to see if block is erased. It is enough to test 785 first sector, because erase happens in one shot */ 786 if (sm_block_erased(&oob)) { 787 kfifo_in(&zone->free_sectors, 788 (unsigned char *)&block, 2); 789 continue; 790 } 791 792 /* If block is marked as bad, skip it */ 793 /* This assumes we can trust first sector*/ 794 /* However the way the block valid status is defined, ensures 795 very low probability of failure here */ 796 if (!sm_block_valid(&oob)) { 797 dbg("PH %04d <-> <marked bad>", block); 798 continue; 799 } 800 801 802 lba = sm_read_lba(&oob); 803 804 /* Invalid LBA means that block is damaged. */ 805 /* We can try to erase it, or mark it as bad, but 806 lets leave that to recovery application */ 807 if (lba == -2 || lba >= ftl->max_lba) { 808 dbg("PH %04d <-> LBA %04d(bad)", block, lba); 809 continue; 810 } 811 812 813 /* If there is no collision, 814 just put the sector in the FTL table */ 815 if (zone->lba_to_phys_table[lba] < 0) { 816 dbg_verbose("PH %04d <-> LBA %04d", block, lba); 817 zone->lba_to_phys_table[lba] = block; 818 continue; 819 } 820 821 sm_printk("collision" 822 " of LBA %d between blocks %d and %d in zone %d", 823 lba, zone->lba_to_phys_table[lba], block, zone_num); 824 825 /* Test that this block is valid*/ 826 if (sm_check_block(ftl, zone_num, block)) 827 continue; 828 829 /* Test now the old block */ 830 if (sm_check_block(ftl, zone_num, 831 zone->lba_to_phys_table[lba])) { 832 zone->lba_to_phys_table[lba] = block; 833 continue; 834 } 835 836 /* If both blocks are valid and share same LBA, it means that 837 they hold different versions of same data. It not 838 known which is more recent, thus just erase one of them 839 */ 840 sm_printk("both blocks are valid, erasing the later"); 841 sm_erase_block(ftl, zone_num, block, 1); 842 } 843 844 dbg("zone initialized"); 845 zone->initialized = 1; 846 847 /* No free sectors, means that the zone is heavily damaged, write won't 848 work, but it can still can be (partially) read */ 849 if (!kfifo_len(&zone->free_sectors)) { 850 sm_printk("no free blocks in zone %d", zone_num); 851 return 0; 852 } 853 854 /* Randomize first block we write to */ 855 get_random_bytes(&i, 2); 856 i %= (kfifo_len(&zone->free_sectors) / 2); 857 858 while (i--) { 859 len = kfifo_out(&zone->free_sectors, 860 (unsigned char *)&block, 2); 861 WARN_ON(len != 2); 862 kfifo_in(&zone->free_sectors, (const unsigned char *)&block, 2); 863 } 864 return 0; 865 } 866 867 /* Get and automatically initialize an FTL mapping for one zone */ 868 static struct ftl_zone *sm_get_zone(struct sm_ftl *ftl, int zone_num) 869 { 870 struct ftl_zone *zone; 871 int error; 872 873 BUG_ON(zone_num >= ftl->zone_count); 874 zone = &ftl->zones[zone_num]; 875 876 if (!zone->initialized) { 877 error = sm_init_zone(ftl, zone_num); 878 879 if (error) 880 return ERR_PTR(error); 881 } 882 return zone; 883 } 884 885 886 /* ----------------- cache handling ------------------------------------------*/ 887 888 /* Initialize the one block cache */ 889 static void sm_cache_init(struct sm_ftl *ftl) 890 { 891 ftl->cache_data_invalid_bitmap = 0xFFFFFFFF; 892 ftl->cache_clean = 1; 893 ftl->cache_zone = -1; 894 ftl->cache_block = -1; 895 /*memset(ftl->cache_data, 0xAA, ftl->block_size);*/ 896 } 897 898 /* Put sector in one block cache */ 899 static void sm_cache_put(struct sm_ftl *ftl, char *buffer, int boffset) 900 { 901 memcpy(ftl->cache_data + boffset, buffer, SM_SECTOR_SIZE); 902 clear_bit(boffset / SM_SECTOR_SIZE, &ftl->cache_data_invalid_bitmap); 903 ftl->cache_clean = 0; 904 } 905 906 /* Read a sector from the cache */ 907 static int sm_cache_get(struct sm_ftl *ftl, char *buffer, int boffset) 908 { 909 if (test_bit(boffset / SM_SECTOR_SIZE, 910 &ftl->cache_data_invalid_bitmap)) 911 return -1; 912 913 memcpy(buffer, ftl->cache_data + boffset, SM_SECTOR_SIZE); 914 return 0; 915 } 916 917 /* Write the cache to hardware */ 918 static int sm_cache_flush(struct sm_ftl *ftl) 919 { 920 struct ftl_zone *zone; 921 922 int sector_num; 923 uint16_t write_sector; 924 int zone_num = ftl->cache_zone; 925 int block_num; 926 927 if (ftl->cache_clean) 928 return 0; 929 930 if (ftl->unstable) 931 return -EIO; 932 933 BUG_ON(zone_num < 0); 934 zone = &ftl->zones[zone_num]; 935 block_num = zone->lba_to_phys_table[ftl->cache_block]; 936 937 938 /* Try to read all unread areas of the cache block*/ 939 for_each_set_bit(sector_num, &ftl->cache_data_invalid_bitmap, 940 ftl->block_size / SM_SECTOR_SIZE) { 941 942 if (!sm_read_sector(ftl, 943 zone_num, block_num, sector_num * SM_SECTOR_SIZE, 944 ftl->cache_data + sector_num * SM_SECTOR_SIZE, NULL)) 945 clear_bit(sector_num, 946 &ftl->cache_data_invalid_bitmap); 947 } 948 restart: 949 950 if (ftl->unstable) 951 return -EIO; 952 953 /* If there are no spare blocks, */ 954 /* we could still continue by erasing/writing the current block, 955 but for such worn out media it doesn't worth the trouble, 956 and the dangers */ 957 if (kfifo_out(&zone->free_sectors, 958 (unsigned char *)&write_sector, 2) != 2) { 959 dbg("no free sectors for write!"); 960 return -EIO; 961 } 962 963 964 if (sm_write_block(ftl, ftl->cache_data, zone_num, write_sector, 965 ftl->cache_block, ftl->cache_data_invalid_bitmap)) 966 goto restart; 967 968 /* Update the FTL table */ 969 zone->lba_to_phys_table[ftl->cache_block] = write_sector; 970 971 /* Write succesfull, so erase and free the old block */ 972 if (block_num > 0) 973 sm_erase_block(ftl, zone_num, block_num, 1); 974 975 sm_cache_init(ftl); 976 return 0; 977 } 978 979 980 /* flush timer, runs a second after last write */ 981 static void sm_cache_flush_timer(struct timer_list *t) 982 { 983 struct sm_ftl *ftl = from_timer(ftl, t, timer); 984 queue_work(cache_flush_workqueue, &ftl->flush_work); 985 } 986 987 /* cache flush work, kicked by timer */ 988 static void sm_cache_flush_work(struct work_struct *work) 989 { 990 struct sm_ftl *ftl = container_of(work, struct sm_ftl, flush_work); 991 mutex_lock(&ftl->mutex); 992 sm_cache_flush(ftl); 993 mutex_unlock(&ftl->mutex); 994 return; 995 } 996 997 /* ---------------- outside interface -------------------------------------- */ 998 999 /* outside interface: read a sector */ 1000 static int sm_read(struct mtd_blktrans_dev *dev, 1001 unsigned long sect_no, char *buf) 1002 { 1003 struct sm_ftl *ftl = dev->priv; 1004 struct ftl_zone *zone; 1005 int error = 0, in_cache = 0; 1006 int zone_num, block, boffset; 1007 1008 sm_break_offset(ftl, sect_no << 9, &zone_num, &block, &boffset); 1009 mutex_lock(&ftl->mutex); 1010 1011 1012 zone = sm_get_zone(ftl, zone_num); 1013 if (IS_ERR(zone)) { 1014 error = PTR_ERR(zone); 1015 goto unlock; 1016 } 1017 1018 /* Have to look at cache first */ 1019 if (ftl->cache_zone == zone_num && ftl->cache_block == block) { 1020 in_cache = 1; 1021 if (!sm_cache_get(ftl, buf, boffset)) 1022 goto unlock; 1023 } 1024 1025 /* Translate the block and return if doesn't exist in the table */ 1026 block = zone->lba_to_phys_table[block]; 1027 1028 if (block == -1) { 1029 memset(buf, 0xFF, SM_SECTOR_SIZE); 1030 goto unlock; 1031 } 1032 1033 if (sm_read_sector(ftl, zone_num, block, boffset, buf, NULL)) { 1034 error = -EIO; 1035 goto unlock; 1036 } 1037 1038 if (in_cache) 1039 sm_cache_put(ftl, buf, boffset); 1040 unlock: 1041 mutex_unlock(&ftl->mutex); 1042 return error; 1043 } 1044 1045 /* outside interface: write a sector */ 1046 static int sm_write(struct mtd_blktrans_dev *dev, 1047 unsigned long sec_no, char *buf) 1048 { 1049 struct sm_ftl *ftl = dev->priv; 1050 struct ftl_zone *zone; 1051 int error = 0, zone_num, block, boffset; 1052 1053 BUG_ON(ftl->readonly); 1054 sm_break_offset(ftl, sec_no << 9, &zone_num, &block, &boffset); 1055 1056 /* No need in flush thread running now */ 1057 del_timer(&ftl->timer); 1058 mutex_lock(&ftl->mutex); 1059 1060 zone = sm_get_zone(ftl, zone_num); 1061 if (IS_ERR(zone)) { 1062 error = PTR_ERR(zone); 1063 goto unlock; 1064 } 1065 1066 /* If entry is not in cache, flush it */ 1067 if (ftl->cache_block != block || ftl->cache_zone != zone_num) { 1068 1069 error = sm_cache_flush(ftl); 1070 if (error) 1071 goto unlock; 1072 1073 ftl->cache_block = block; 1074 ftl->cache_zone = zone_num; 1075 } 1076 1077 sm_cache_put(ftl, buf, boffset); 1078 unlock: 1079 mod_timer(&ftl->timer, jiffies + msecs_to_jiffies(cache_timeout)); 1080 mutex_unlock(&ftl->mutex); 1081 return error; 1082 } 1083 1084 /* outside interface: flush everything */ 1085 static int sm_flush(struct mtd_blktrans_dev *dev) 1086 { 1087 struct sm_ftl *ftl = dev->priv; 1088 int retval; 1089 1090 mutex_lock(&ftl->mutex); 1091 retval = sm_cache_flush(ftl); 1092 mutex_unlock(&ftl->mutex); 1093 return retval; 1094 } 1095 1096 /* outside interface: device is released */ 1097 static void sm_release(struct mtd_blktrans_dev *dev) 1098 { 1099 struct sm_ftl *ftl = dev->priv; 1100 1101 mutex_lock(&ftl->mutex); 1102 del_timer_sync(&ftl->timer); 1103 cancel_work_sync(&ftl->flush_work); 1104 sm_cache_flush(ftl); 1105 mutex_unlock(&ftl->mutex); 1106 } 1107 1108 /* outside interface: get geometry */ 1109 static int sm_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo) 1110 { 1111 struct sm_ftl *ftl = dev->priv; 1112 geo->heads = ftl->heads; 1113 geo->sectors = ftl->sectors; 1114 geo->cylinders = ftl->cylinders; 1115 return 0; 1116 } 1117 1118 /* external interface: main initialization function */ 1119 static void sm_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd) 1120 { 1121 struct mtd_blktrans_dev *trans; 1122 struct sm_ftl *ftl; 1123 1124 /* Allocate & initialize our private structure */ 1125 ftl = kzalloc(sizeof(struct sm_ftl), GFP_KERNEL); 1126 if (!ftl) 1127 goto error1; 1128 1129 1130 mutex_init(&ftl->mutex); 1131 timer_setup(&ftl->timer, sm_cache_flush_timer, 0); 1132 INIT_WORK(&ftl->flush_work, sm_cache_flush_work); 1133 1134 /* Read media information */ 1135 if (sm_get_media_info(ftl, mtd)) { 1136 dbg("found unsupported mtd device, aborting"); 1137 goto error2; 1138 } 1139 1140 1141 /* Allocate temporary CIS buffer for read retry support */ 1142 ftl->cis_buffer = kzalloc(SM_SECTOR_SIZE, GFP_KERNEL); 1143 if (!ftl->cis_buffer) 1144 goto error2; 1145 1146 /* Allocate zone array, it will be initialized on demand */ 1147 ftl->zones = kcalloc(ftl->zone_count, sizeof(struct ftl_zone), 1148 GFP_KERNEL); 1149 if (!ftl->zones) 1150 goto error3; 1151 1152 /* Allocate the cache*/ 1153 ftl->cache_data = kzalloc(ftl->block_size, GFP_KERNEL); 1154 1155 if (!ftl->cache_data) 1156 goto error4; 1157 1158 sm_cache_init(ftl); 1159 1160 1161 /* Allocate upper layer structure and initialize it */ 1162 trans = kzalloc(sizeof(struct mtd_blktrans_dev), GFP_KERNEL); 1163 if (!trans) 1164 goto error5; 1165 1166 ftl->trans = trans; 1167 trans->priv = ftl; 1168 1169 trans->tr = tr; 1170 trans->mtd = mtd; 1171 trans->devnum = -1; 1172 trans->size = (ftl->block_size * ftl->max_lba * ftl->zone_count) >> 9; 1173 trans->readonly = ftl->readonly; 1174 1175 if (sm_find_cis(ftl)) { 1176 dbg("CIS not found on mtd device, aborting"); 1177 goto error6; 1178 } 1179 1180 ftl->disk_attributes = sm_create_sysfs_attributes(ftl); 1181 if (!ftl->disk_attributes) 1182 goto error6; 1183 trans->disk_attributes = ftl->disk_attributes; 1184 1185 sm_printk("Found %d MiB xD/SmartMedia FTL on mtd%d", 1186 (int)(mtd->size / (1024 * 1024)), mtd->index); 1187 1188 dbg("FTL layout:"); 1189 dbg("%d zone(s), each consists of %d blocks (+%d spares)", 1190 ftl->zone_count, ftl->max_lba, 1191 ftl->zone_size - ftl->max_lba); 1192 dbg("each block consists of %d bytes", 1193 ftl->block_size); 1194 1195 1196 /* Register device*/ 1197 if (add_mtd_blktrans_dev(trans)) { 1198 dbg("error in mtdblktrans layer"); 1199 goto error6; 1200 } 1201 return; 1202 error6: 1203 kfree(trans); 1204 error5: 1205 kfree(ftl->cache_data); 1206 error4: 1207 kfree(ftl->zones); 1208 error3: 1209 kfree(ftl->cis_buffer); 1210 error2: 1211 kfree(ftl); 1212 error1: 1213 return; 1214 } 1215 1216 /* main interface: device {surprise,} removal */ 1217 static void sm_remove_dev(struct mtd_blktrans_dev *dev) 1218 { 1219 struct sm_ftl *ftl = dev->priv; 1220 int i; 1221 1222 del_mtd_blktrans_dev(dev); 1223 ftl->trans = NULL; 1224 1225 for (i = 0 ; i < ftl->zone_count; i++) { 1226 1227 if (!ftl->zones[i].initialized) 1228 continue; 1229 1230 kfree(ftl->zones[i].lba_to_phys_table); 1231 kfifo_free(&ftl->zones[i].free_sectors); 1232 } 1233 1234 sm_delete_sysfs_attributes(ftl); 1235 kfree(ftl->cis_buffer); 1236 kfree(ftl->zones); 1237 kfree(ftl->cache_data); 1238 kfree(ftl); 1239 } 1240 1241 static struct mtd_blktrans_ops sm_ftl_ops = { 1242 .name = "smblk", 1243 .major = 0, 1244 .part_bits = SM_FTL_PARTN_BITS, 1245 .blksize = SM_SECTOR_SIZE, 1246 .getgeo = sm_getgeo, 1247 1248 .add_mtd = sm_add_mtd, 1249 .remove_dev = sm_remove_dev, 1250 1251 .readsect = sm_read, 1252 .writesect = sm_write, 1253 1254 .flush = sm_flush, 1255 .release = sm_release, 1256 1257 .owner = THIS_MODULE, 1258 }; 1259 1260 static __init int sm_module_init(void) 1261 { 1262 int error = 0; 1263 1264 cache_flush_workqueue = create_freezable_workqueue("smflush"); 1265 if (!cache_flush_workqueue) 1266 return -ENOMEM; 1267 1268 error = register_mtd_blktrans(&sm_ftl_ops); 1269 if (error) 1270 destroy_workqueue(cache_flush_workqueue); 1271 return error; 1272 1273 } 1274 1275 static void __exit sm_module_exit(void) 1276 { 1277 destroy_workqueue(cache_flush_workqueue); 1278 deregister_mtd_blktrans(&sm_ftl_ops); 1279 } 1280 1281 module_init(sm_module_init); 1282 module_exit(sm_module_exit); 1283 1284 MODULE_LICENSE("GPL"); 1285 MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>"); 1286 MODULE_DESCRIPTION("Smartmedia/xD mtd translation layer"); 1287