1 /* 2 * Copyright © 2009 - Maxim Levitsky 3 * SmartMedia/xD translation layer 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 */ 9 10 #include <linux/kernel.h> 11 #include <linux/module.h> 12 #include <linux/random.h> 13 #include <linux/hdreg.h> 14 #include <linux/kthread.h> 15 #include <linux/freezer.h> 16 #include <linux/sysfs.h> 17 #include <linux/bitops.h> 18 #include <linux/slab.h> 19 #include <linux/mtd/nand_ecc.h> 20 #include "nand/sm_common.h" 21 #include "sm_ftl.h" 22 23 24 25 static struct workqueue_struct *cache_flush_workqueue; 26 27 static int cache_timeout = 1000; 28 module_param(cache_timeout, int, S_IRUGO); 29 MODULE_PARM_DESC(cache_timeout, 30 "Timeout (in ms) for cache flush (1000 ms default"); 31 32 static int debug; 33 module_param(debug, int, S_IRUGO | S_IWUSR); 34 MODULE_PARM_DESC(debug, "Debug level (0-2)"); 35 36 37 /* ------------------- sysfs attributes ---------------------------------- */ 38 struct sm_sysfs_attribute { 39 struct device_attribute dev_attr; 40 char *data; 41 int len; 42 }; 43 44 static ssize_t sm_attr_show(struct device *dev, struct device_attribute *attr, 45 char *buf) 46 { 47 struct sm_sysfs_attribute *sm_attr = 48 container_of(attr, struct sm_sysfs_attribute, dev_attr); 49 50 strncpy(buf, sm_attr->data, sm_attr->len); 51 return sm_attr->len; 52 } 53 54 55 #define NUM_ATTRIBUTES 1 56 #define SM_CIS_VENDOR_OFFSET 0x59 57 static struct attribute_group *sm_create_sysfs_attributes(struct sm_ftl *ftl) 58 { 59 struct attribute_group *attr_group; 60 struct attribute **attributes; 61 struct sm_sysfs_attribute *vendor_attribute; 62 63 int vendor_len = strnlen(ftl->cis_buffer + SM_CIS_VENDOR_OFFSET, 64 SM_SMALL_PAGE - SM_CIS_VENDOR_OFFSET); 65 66 char *vendor = kmalloc(vendor_len, GFP_KERNEL); 67 if (!vendor) 68 goto error1; 69 memcpy(vendor, ftl->cis_buffer + SM_CIS_VENDOR_OFFSET, vendor_len); 70 vendor[vendor_len] = 0; 71 72 /* Initialize sysfs attributes */ 73 vendor_attribute = 74 kzalloc(sizeof(struct sm_sysfs_attribute), GFP_KERNEL); 75 if (!vendor_attribute) 76 goto error2; 77 78 sysfs_attr_init(&vendor_attribute->dev_attr.attr); 79 80 vendor_attribute->data = vendor; 81 vendor_attribute->len = vendor_len; 82 vendor_attribute->dev_attr.attr.name = "vendor"; 83 vendor_attribute->dev_attr.attr.mode = S_IRUGO; 84 vendor_attribute->dev_attr.show = sm_attr_show; 85 86 87 /* Create array of pointers to the attributes */ 88 attributes = kzalloc(sizeof(struct attribute *) * (NUM_ATTRIBUTES + 1), 89 GFP_KERNEL); 90 if (!attributes) 91 goto error3; 92 attributes[0] = &vendor_attribute->dev_attr.attr; 93 94 /* Finally create the attribute group */ 95 attr_group = kzalloc(sizeof(struct attribute_group), GFP_KERNEL); 96 if (!attr_group) 97 goto error4; 98 attr_group->attrs = attributes; 99 return attr_group; 100 error4: 101 kfree(attributes); 102 error3: 103 kfree(vendor_attribute); 104 error2: 105 kfree(vendor); 106 error1: 107 return NULL; 108 } 109 110 static void sm_delete_sysfs_attributes(struct sm_ftl *ftl) 111 { 112 struct attribute **attributes = ftl->disk_attributes->attrs; 113 int i; 114 115 for (i = 0; attributes[i] ; i++) { 116 117 struct device_attribute *dev_attr = container_of(attributes[i], 118 struct device_attribute, attr); 119 120 struct sm_sysfs_attribute *sm_attr = 121 container_of(dev_attr, 122 struct sm_sysfs_attribute, dev_attr); 123 124 kfree(sm_attr->data); 125 kfree(sm_attr); 126 } 127 128 kfree(ftl->disk_attributes->attrs); 129 kfree(ftl->disk_attributes); 130 } 131 132 133 /* ----------------------- oob helpers -------------------------------------- */ 134 135 static int sm_get_lba(uint8_t *lba) 136 { 137 /* check fixed bits */ 138 if ((lba[0] & 0xF8) != 0x10) 139 return -2; 140 141 /* check parity - endianness doesn't matter */ 142 if (hweight16(*(uint16_t *)lba) & 1) 143 return -2; 144 145 return (lba[1] >> 1) | ((lba[0] & 0x07) << 7); 146 } 147 148 149 /* 150 * Read LBA associated with block 151 * returns -1, if block is erased 152 * returns -2 if error happens 153 */ 154 static int sm_read_lba(struct sm_oob *oob) 155 { 156 static const uint32_t erased_pattern[4] = { 157 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF }; 158 159 uint16_t lba_test; 160 int lba; 161 162 /* First test for erased block */ 163 if (!memcmp(oob, erased_pattern, SM_OOB_SIZE)) 164 return -1; 165 166 /* Now check is both copies of the LBA differ too much */ 167 lba_test = *(uint16_t *)oob->lba_copy1 ^ *(uint16_t*)oob->lba_copy2; 168 if (lba_test && !is_power_of_2(lba_test)) 169 return -2; 170 171 /* And read it */ 172 lba = sm_get_lba(oob->lba_copy1); 173 174 if (lba == -2) 175 lba = sm_get_lba(oob->lba_copy2); 176 177 return lba; 178 } 179 180 static void sm_write_lba(struct sm_oob *oob, uint16_t lba) 181 { 182 uint8_t tmp[2]; 183 184 WARN_ON(lba >= 1000); 185 186 tmp[0] = 0x10 | ((lba >> 7) & 0x07); 187 tmp[1] = (lba << 1) & 0xFF; 188 189 if (hweight16(*(uint16_t *)tmp) & 0x01) 190 tmp[1] |= 1; 191 192 oob->lba_copy1[0] = oob->lba_copy2[0] = tmp[0]; 193 oob->lba_copy1[1] = oob->lba_copy2[1] = tmp[1]; 194 } 195 196 197 /* Make offset from parts */ 198 static loff_t sm_mkoffset(struct sm_ftl *ftl, int zone, int block, int boffset) 199 { 200 WARN_ON(boffset & (SM_SECTOR_SIZE - 1)); 201 WARN_ON(zone < 0 || zone >= ftl->zone_count); 202 WARN_ON(block >= ftl->zone_size); 203 WARN_ON(boffset >= ftl->block_size); 204 205 if (block == -1) 206 return -1; 207 208 return (zone * SM_MAX_ZONE_SIZE + block) * ftl->block_size + boffset; 209 } 210 211 /* Breaks offset into parts */ 212 static void sm_break_offset(struct sm_ftl *ftl, loff_t offset, 213 int *zone, int *block, int *boffset) 214 { 215 *boffset = do_div(offset, ftl->block_size); 216 *block = do_div(offset, ftl->max_lba); 217 *zone = offset >= ftl->zone_count ? -1 : offset; 218 } 219 220 /* ---------------------- low level IO ------------------------------------- */ 221 222 static int sm_correct_sector(uint8_t *buffer, struct sm_oob *oob) 223 { 224 uint8_t ecc[3]; 225 226 __nand_calculate_ecc(buffer, SM_SMALL_PAGE, ecc); 227 if (__nand_correct_data(buffer, ecc, oob->ecc1, SM_SMALL_PAGE) < 0) 228 return -EIO; 229 230 buffer += SM_SMALL_PAGE; 231 232 __nand_calculate_ecc(buffer, SM_SMALL_PAGE, ecc); 233 if (__nand_correct_data(buffer, ecc, oob->ecc2, SM_SMALL_PAGE) < 0) 234 return -EIO; 235 return 0; 236 } 237 238 /* Reads a sector + oob*/ 239 static int sm_read_sector(struct sm_ftl *ftl, 240 int zone, int block, int boffset, 241 uint8_t *buffer, struct sm_oob *oob) 242 { 243 struct mtd_info *mtd = ftl->trans->mtd; 244 struct mtd_oob_ops ops; 245 struct sm_oob tmp_oob; 246 int ret = -EIO; 247 int try = 0; 248 249 /* FTL can contain -1 entries that are by default filled with bits */ 250 if (block == -1) { 251 memset(buffer, 0xFF, SM_SECTOR_SIZE); 252 return 0; 253 } 254 255 /* User might not need the oob, but we do for data verification */ 256 if (!oob) 257 oob = &tmp_oob; 258 259 ops.mode = ftl->smallpagenand ? MTD_OPS_RAW : MTD_OPS_PLACE_OOB; 260 ops.ooboffs = 0; 261 ops.ooblen = SM_OOB_SIZE; 262 ops.oobbuf = (void *)oob; 263 ops.len = SM_SECTOR_SIZE; 264 ops.datbuf = buffer; 265 266 again: 267 if (try++) { 268 /* Avoid infinite recursion on CIS reads, sm_recheck_media 269 won't help anyway */ 270 if (zone == 0 && block == ftl->cis_block && boffset == 271 ftl->cis_boffset) 272 return ret; 273 274 /* Test if media is stable */ 275 if (try == 3 || sm_recheck_media(ftl)) 276 return ret; 277 } 278 279 /* Unfortunately, oob read will _always_ succeed, 280 despite card removal..... */ 281 ret = mtd_read_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops); 282 283 /* Test for unknown errors */ 284 if (ret != 0 && !mtd_is_bitflip_or_eccerr(ret)) { 285 dbg("read of block %d at zone %d, failed due to error (%d)", 286 block, zone, ret); 287 goto again; 288 } 289 290 /* Do a basic test on the oob, to guard against returned garbage */ 291 if (oob->reserved != 0xFFFFFFFF && !is_power_of_2(~oob->reserved)) 292 goto again; 293 294 /* This should never happen, unless there is a bug in the mtd driver */ 295 WARN_ON(ops.oobretlen != SM_OOB_SIZE); 296 WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE); 297 298 if (!buffer) 299 return 0; 300 301 /* Test if sector marked as bad */ 302 if (!sm_sector_valid(oob)) { 303 dbg("read of block %d at zone %d, failed because it is marked" 304 " as bad" , block, zone); 305 goto again; 306 } 307 308 /* Test ECC*/ 309 if (mtd_is_eccerr(ret) || 310 (ftl->smallpagenand && sm_correct_sector(buffer, oob))) { 311 312 dbg("read of block %d at zone %d, failed due to ECC error", 313 block, zone); 314 goto again; 315 } 316 317 return 0; 318 } 319 320 /* Writes a sector to media */ 321 static int sm_write_sector(struct sm_ftl *ftl, 322 int zone, int block, int boffset, 323 uint8_t *buffer, struct sm_oob *oob) 324 { 325 struct mtd_oob_ops ops; 326 struct mtd_info *mtd = ftl->trans->mtd; 327 int ret; 328 329 BUG_ON(ftl->readonly); 330 331 if (zone == 0 && (block == ftl->cis_block || block == 0)) { 332 dbg("attempted to write the CIS!"); 333 return -EIO; 334 } 335 336 if (ftl->unstable) 337 return -EIO; 338 339 ops.mode = ftl->smallpagenand ? MTD_OPS_RAW : MTD_OPS_PLACE_OOB; 340 ops.len = SM_SECTOR_SIZE; 341 ops.datbuf = buffer; 342 ops.ooboffs = 0; 343 ops.ooblen = SM_OOB_SIZE; 344 ops.oobbuf = (void *)oob; 345 346 ret = mtd_write_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops); 347 348 /* Now we assume that hardware will catch write bitflip errors */ 349 350 if (ret) { 351 dbg("write to block %d at zone %d, failed with error %d", 352 block, zone, ret); 353 354 sm_recheck_media(ftl); 355 return ret; 356 } 357 358 /* This should never happen, unless there is a bug in the driver */ 359 WARN_ON(ops.oobretlen != SM_OOB_SIZE); 360 WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE); 361 362 return 0; 363 } 364 365 /* ------------------------ block IO ------------------------------------- */ 366 367 /* Write a block using data and lba, and invalid sector bitmap */ 368 static int sm_write_block(struct sm_ftl *ftl, uint8_t *buf, 369 int zone, int block, int lba, 370 unsigned long invalid_bitmap) 371 { 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 " coudn'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 __nand_calculate_ecc(buf + boffset, 399 SM_SMALL_PAGE, oob.ecc1); 400 401 __nand_calculate_ecc(buf + boffset + SM_SMALL_PAGE, 402 SM_SMALL_PAGE, oob.ecc2); 403 } 404 if (!sm_write_sector(ftl, zone, block, boffset, 405 buf + boffset, &oob)) 406 continue; 407 408 if (!retry) { 409 410 /* If write fails. try to erase the block */ 411 /* This is safe, because we never write in blocks 412 that contain valuable data. 413 This is intended to repair block that are marked 414 as erased, but that isn't fully erased*/ 415 416 if (sm_erase_block(ftl, zone, block, 0)) 417 return -EIO; 418 419 retry = 1; 420 goto restart; 421 } else { 422 sm_mark_block_bad(ftl, zone, block); 423 return -EIO; 424 } 425 } 426 return 0; 427 } 428 429 430 /* Mark whole block at offset 'offs' as bad. */ 431 static void sm_mark_block_bad(struct sm_ftl *ftl, int zone, int block) 432 { 433 struct sm_oob oob; 434 int boffset; 435 436 memset(&oob, 0xFF, SM_OOB_SIZE); 437 oob.block_status = 0xF0; 438 439 if (ftl->unstable) 440 return; 441 442 if (sm_recheck_media(ftl)) 443 return; 444 445 sm_printk("marking block %d of zone %d as bad", block, zone); 446 447 /* We aren't checking the return value, because we don't care */ 448 /* This also fails on fake xD cards, but I guess these won't expose 449 any bad blocks till fail completely */ 450 for (boffset = 0; boffset < ftl->block_size; boffset += SM_SECTOR_SIZE) 451 sm_write_sector(ftl, zone, block, boffset, NULL, &oob); 452 } 453 454 /* 455 * Erase a block within a zone 456 * If erase succeeds, it updates free block fifo, otherwise marks block as bad 457 */ 458 static int sm_erase_block(struct sm_ftl *ftl, int zone_num, uint16_t block, 459 int put_free) 460 { 461 struct ftl_zone *zone = &ftl->zones[zone_num]; 462 struct mtd_info *mtd = ftl->trans->mtd; 463 struct erase_info erase; 464 465 erase.mtd = mtd; 466 erase.callback = sm_erase_callback; 467 erase.addr = sm_mkoffset(ftl, zone_num, block, 0); 468 erase.len = ftl->block_size; 469 erase.priv = (u_long)ftl; 470 471 if (ftl->unstable) 472 return -EIO; 473 474 BUG_ON(ftl->readonly); 475 476 if (zone_num == 0 && (block == ftl->cis_block || block == 0)) { 477 sm_printk("attempted to erase the CIS!"); 478 return -EIO; 479 } 480 481 if (mtd_erase(mtd, &erase)) { 482 sm_printk("erase of block %d in zone %d failed", 483 block, zone_num); 484 goto error; 485 } 486 487 if (erase.state == MTD_ERASE_PENDING) 488 wait_for_completion(&ftl->erase_completion); 489 490 if (erase.state != MTD_ERASE_DONE) { 491 sm_printk("erase of block %d in zone %d failed after wait", 492 block, zone_num); 493 goto error; 494 } 495 496 if (put_free) 497 kfifo_in(&zone->free_sectors, 498 (const unsigned char *)&block, sizeof(block)); 499 500 return 0; 501 error: 502 sm_mark_block_bad(ftl, zone_num, block); 503 return -EIO; 504 } 505 506 static void sm_erase_callback(struct erase_info *self) 507 { 508 struct sm_ftl *ftl = (struct sm_ftl *)self->priv; 509 complete(&ftl->erase_completion); 510 } 511 512 /* Thoroughly test that block is valid. */ 513 static int sm_check_block(struct sm_ftl *ftl, int zone, int block) 514 { 515 int boffset; 516 struct sm_oob oob; 517 int lbas[] = { -3, 0, 0, 0 }; 518 int i = 0; 519 int test_lba; 520 521 522 /* First just check that block doesn't look fishy */ 523 /* Only blocks that are valid or are sliced in two parts, are 524 accepted */ 525 for (boffset = 0; boffset < ftl->block_size; 526 boffset += SM_SECTOR_SIZE) { 527 528 /* This shouldn't happen anyway */ 529 if (sm_read_sector(ftl, zone, block, boffset, NULL, &oob)) 530 return -2; 531 532 test_lba = sm_read_lba(&oob); 533 534 if (lbas[i] != test_lba) 535 lbas[++i] = test_lba; 536 537 /* If we found three different LBAs, something is fishy */ 538 if (i == 3) 539 return -EIO; 540 } 541 542 /* If the block is sliced (partially erased usually) erase it */ 543 if (i == 2) { 544 sm_erase_block(ftl, zone, block, 1); 545 return 1; 546 } 547 548 return 0; 549 } 550 551 /* ----------------- media scanning --------------------------------- */ 552 static const struct chs_entry chs_table[] = { 553 { 1, 125, 4, 4 }, 554 { 2, 125, 4, 8 }, 555 { 4, 250, 4, 8 }, 556 { 8, 250, 4, 16 }, 557 { 16, 500, 4, 16 }, 558 { 32, 500, 8, 16 }, 559 { 64, 500, 8, 32 }, 560 { 128, 500, 16, 32 }, 561 { 256, 1000, 16, 32 }, 562 { 512, 1015, 32, 63 }, 563 { 1024, 985, 33, 63 }, 564 { 2048, 985, 33, 63 }, 565 { 0 }, 566 }; 567 568 569 static const uint8_t cis_signature[] = { 570 0x01, 0x03, 0xD9, 0x01, 0xFF, 0x18, 0x02, 0xDF, 0x01, 0x20 571 }; 572 /* Find out media parameters. 573 * This ideally has to be based on nand id, but for now device size is enough */ 574 static int sm_get_media_info(struct sm_ftl *ftl, struct mtd_info *mtd) 575 { 576 int i; 577 int size_in_megs = mtd->size / (1024 * 1024); 578 579 ftl->readonly = mtd->type == MTD_ROM; 580 581 /* Manual settings for very old devices */ 582 ftl->zone_count = 1; 583 ftl->smallpagenand = 0; 584 585 switch (size_in_megs) { 586 case 1: 587 /* 1 MiB flash/rom SmartMedia card (256 byte pages)*/ 588 ftl->zone_size = 256; 589 ftl->max_lba = 250; 590 ftl->block_size = 8 * SM_SECTOR_SIZE; 591 ftl->smallpagenand = 1; 592 593 break; 594 case 2: 595 /* 2 MiB flash SmartMedia (256 byte pages)*/ 596 if (mtd->writesize == SM_SMALL_PAGE) { 597 ftl->zone_size = 512; 598 ftl->max_lba = 500; 599 ftl->block_size = 8 * SM_SECTOR_SIZE; 600 ftl->smallpagenand = 1; 601 /* 2 MiB rom SmartMedia */ 602 } else { 603 604 if (!ftl->readonly) 605 return -ENODEV; 606 607 ftl->zone_size = 256; 608 ftl->max_lba = 250; 609 ftl->block_size = 16 * SM_SECTOR_SIZE; 610 } 611 break; 612 case 4: 613 /* 4 MiB flash/rom SmartMedia device */ 614 ftl->zone_size = 512; 615 ftl->max_lba = 500; 616 ftl->block_size = 16 * SM_SECTOR_SIZE; 617 break; 618 case 8: 619 /* 8 MiB flash/rom SmartMedia device */ 620 ftl->zone_size = 1024; 621 ftl->max_lba = 1000; 622 ftl->block_size = 16 * SM_SECTOR_SIZE; 623 } 624 625 /* Minimum xD size is 16MiB. Also, all xD cards have standard zone 626 sizes. SmartMedia cards exist up to 128 MiB and have same layout*/ 627 if (size_in_megs >= 16) { 628 ftl->zone_count = size_in_megs / 16; 629 ftl->zone_size = 1024; 630 ftl->max_lba = 1000; 631 ftl->block_size = 32 * SM_SECTOR_SIZE; 632 } 633 634 /* Test for proper write,erase and oob sizes */ 635 if (mtd->erasesize > ftl->block_size) 636 return -ENODEV; 637 638 if (mtd->writesize > SM_SECTOR_SIZE) 639 return -ENODEV; 640 641 if (ftl->smallpagenand && mtd->oobsize < SM_SMALL_OOB_SIZE) 642 return -ENODEV; 643 644 if (!ftl->smallpagenand && mtd->oobsize < SM_OOB_SIZE) 645 return -ENODEV; 646 647 /* We use OOB */ 648 if (!mtd_has_oob(mtd)) 649 return -ENODEV; 650 651 /* Find geometry information */ 652 for (i = 0 ; i < ARRAY_SIZE(chs_table) ; i++) { 653 if (chs_table[i].size == size_in_megs) { 654 ftl->cylinders = chs_table[i].cyl; 655 ftl->heads = chs_table[i].head; 656 ftl->sectors = chs_table[i].sec; 657 return 0; 658 } 659 } 660 661 sm_printk("media has unknown size : %dMiB", size_in_megs); 662 ftl->cylinders = 985; 663 ftl->heads = 33; 664 ftl->sectors = 63; 665 return 0; 666 } 667 668 /* Validate the CIS */ 669 static int sm_read_cis(struct sm_ftl *ftl) 670 { 671 struct sm_oob oob; 672 673 if (sm_read_sector(ftl, 674 0, ftl->cis_block, ftl->cis_boffset, ftl->cis_buffer, &oob)) 675 return -EIO; 676 677 if (!sm_sector_valid(&oob) || !sm_block_valid(&oob)) 678 return -EIO; 679 680 if (!memcmp(ftl->cis_buffer + ftl->cis_page_offset, 681 cis_signature, sizeof(cis_signature))) { 682 return 0; 683 } 684 685 return -EIO; 686 } 687 688 /* Scan the media for the CIS */ 689 static int sm_find_cis(struct sm_ftl *ftl) 690 { 691 struct sm_oob oob; 692 int block, boffset; 693 int block_found = 0; 694 int cis_found = 0; 695 696 /* Search for first valid block */ 697 for (block = 0 ; block < ftl->zone_size - ftl->max_lba ; block++) { 698 699 if (sm_read_sector(ftl, 0, block, 0, NULL, &oob)) 700 continue; 701 702 if (!sm_block_valid(&oob)) 703 continue; 704 block_found = 1; 705 break; 706 } 707 708 if (!block_found) 709 return -EIO; 710 711 /* Search for first valid sector in this block */ 712 for (boffset = 0 ; boffset < ftl->block_size; 713 boffset += SM_SECTOR_SIZE) { 714 715 if (sm_read_sector(ftl, 0, block, boffset, NULL, &oob)) 716 continue; 717 718 if (!sm_sector_valid(&oob)) 719 continue; 720 break; 721 } 722 723 if (boffset == ftl->block_size) 724 return -EIO; 725 726 ftl->cis_block = block; 727 ftl->cis_boffset = boffset; 728 ftl->cis_page_offset = 0; 729 730 cis_found = !sm_read_cis(ftl); 731 732 if (!cis_found) { 733 ftl->cis_page_offset = SM_SMALL_PAGE; 734 cis_found = !sm_read_cis(ftl); 735 } 736 737 if (cis_found) { 738 dbg("CIS block found at offset %x", 739 block * ftl->block_size + 740 boffset + ftl->cis_page_offset); 741 return 0; 742 } 743 return -EIO; 744 } 745 746 /* Basic test to determine if underlying mtd device if functional */ 747 static int sm_recheck_media(struct sm_ftl *ftl) 748 { 749 if (sm_read_cis(ftl)) { 750 751 if (!ftl->unstable) { 752 sm_printk("media unstable, not allowing writes"); 753 ftl->unstable = 1; 754 } 755 return -EIO; 756 } 757 return 0; 758 } 759 760 /* Initialize a FTL zone */ 761 static int sm_init_zone(struct sm_ftl *ftl, int zone_num) 762 { 763 struct ftl_zone *zone = &ftl->zones[zone_num]; 764 struct sm_oob oob; 765 uint16_t block; 766 int lba; 767 int i = 0; 768 int len; 769 770 dbg("initializing zone %d", zone_num); 771 772 /* Allocate memory for FTL table */ 773 zone->lba_to_phys_table = kmalloc(ftl->max_lba * 2, GFP_KERNEL); 774 775 if (!zone->lba_to_phys_table) 776 return -ENOMEM; 777 memset(zone->lba_to_phys_table, -1, ftl->max_lba * 2); 778 779 780 /* Allocate memory for free sectors FIFO */ 781 if (kfifo_alloc(&zone->free_sectors, ftl->zone_size * 2, GFP_KERNEL)) { 782 kfree(zone->lba_to_phys_table); 783 return -ENOMEM; 784 } 785 786 /* Now scan the zone */ 787 for (block = 0 ; block < ftl->zone_size ; block++) { 788 789 /* Skip blocks till the CIS (including) */ 790 if (zone_num == 0 && block <= ftl->cis_block) 791 continue; 792 793 /* Read the oob of first sector */ 794 if (sm_read_sector(ftl, zone_num, block, 0, NULL, &oob)) 795 return -EIO; 796 797 /* Test to see if block is erased. It is enough to test 798 first sector, because erase happens in one shot */ 799 if (sm_block_erased(&oob)) { 800 kfifo_in(&zone->free_sectors, 801 (unsigned char *)&block, 2); 802 continue; 803 } 804 805 /* If block is marked as bad, skip it */ 806 /* This assumes we can trust first sector*/ 807 /* However the way the block valid status is defined, ensures 808 very low probability of failure here */ 809 if (!sm_block_valid(&oob)) { 810 dbg("PH %04d <-> <marked bad>", block); 811 continue; 812 } 813 814 815 lba = sm_read_lba(&oob); 816 817 /* Invalid LBA means that block is damaged. */ 818 /* We can try to erase it, or mark it as bad, but 819 lets leave that to recovery application */ 820 if (lba == -2 || lba >= ftl->max_lba) { 821 dbg("PH %04d <-> LBA %04d(bad)", block, lba); 822 continue; 823 } 824 825 826 /* If there is no collision, 827 just put the sector in the FTL table */ 828 if (zone->lba_to_phys_table[lba] < 0) { 829 dbg_verbose("PH %04d <-> LBA %04d", block, lba); 830 zone->lba_to_phys_table[lba] = block; 831 continue; 832 } 833 834 sm_printk("collision" 835 " of LBA %d between blocks %d and %d in zone %d", 836 lba, zone->lba_to_phys_table[lba], block, zone_num); 837 838 /* Test that this block is valid*/ 839 if (sm_check_block(ftl, zone_num, block)) 840 continue; 841 842 /* Test now the old block */ 843 if (sm_check_block(ftl, zone_num, 844 zone->lba_to_phys_table[lba])) { 845 zone->lba_to_phys_table[lba] = block; 846 continue; 847 } 848 849 /* If both blocks are valid and share same LBA, it means that 850 they hold different versions of same data. It not 851 known which is more recent, thus just erase one of them 852 */ 853 sm_printk("both blocks are valid, erasing the later"); 854 sm_erase_block(ftl, zone_num, block, 1); 855 } 856 857 dbg("zone initialized"); 858 zone->initialized = 1; 859 860 /* No free sectors, means that the zone is heavily damaged, write won't 861 work, but it can still can be (partially) read */ 862 if (!kfifo_len(&zone->free_sectors)) { 863 sm_printk("no free blocks in zone %d", zone_num); 864 return 0; 865 } 866 867 /* Randomize first block we write to */ 868 get_random_bytes(&i, 2); 869 i %= (kfifo_len(&zone->free_sectors) / 2); 870 871 while (i--) { 872 len = kfifo_out(&zone->free_sectors, 873 (unsigned char *)&block, 2); 874 WARN_ON(len != 2); 875 kfifo_in(&zone->free_sectors, (const unsigned char *)&block, 2); 876 } 877 return 0; 878 } 879 880 /* Get and automatically initialize an FTL mapping for one zone */ 881 static struct ftl_zone *sm_get_zone(struct sm_ftl *ftl, int zone_num) 882 { 883 struct ftl_zone *zone; 884 int error; 885 886 BUG_ON(zone_num >= ftl->zone_count); 887 zone = &ftl->zones[zone_num]; 888 889 if (!zone->initialized) { 890 error = sm_init_zone(ftl, zone_num); 891 892 if (error) 893 return ERR_PTR(error); 894 } 895 return zone; 896 } 897 898 899 /* ----------------- cache handling ------------------------------------------*/ 900 901 /* Initialize the one block cache */ 902 static void sm_cache_init(struct sm_ftl *ftl) 903 { 904 ftl->cache_data_invalid_bitmap = 0xFFFFFFFF; 905 ftl->cache_clean = 1; 906 ftl->cache_zone = -1; 907 ftl->cache_block = -1; 908 /*memset(ftl->cache_data, 0xAA, ftl->block_size);*/ 909 } 910 911 /* Put sector in one block cache */ 912 static void sm_cache_put(struct sm_ftl *ftl, char *buffer, int boffset) 913 { 914 memcpy(ftl->cache_data + boffset, buffer, SM_SECTOR_SIZE); 915 clear_bit(boffset / SM_SECTOR_SIZE, &ftl->cache_data_invalid_bitmap); 916 ftl->cache_clean = 0; 917 } 918 919 /* Read a sector from the cache */ 920 static int sm_cache_get(struct sm_ftl *ftl, char *buffer, int boffset) 921 { 922 if (test_bit(boffset / SM_SECTOR_SIZE, 923 &ftl->cache_data_invalid_bitmap)) 924 return -1; 925 926 memcpy(buffer, ftl->cache_data + boffset, SM_SECTOR_SIZE); 927 return 0; 928 } 929 930 /* Write the cache to hardware */ 931 static int sm_cache_flush(struct sm_ftl *ftl) 932 { 933 struct ftl_zone *zone; 934 935 int sector_num; 936 uint16_t write_sector; 937 int zone_num = ftl->cache_zone; 938 int block_num; 939 940 if (ftl->cache_clean) 941 return 0; 942 943 if (ftl->unstable) 944 return -EIO; 945 946 BUG_ON(zone_num < 0); 947 zone = &ftl->zones[zone_num]; 948 block_num = zone->lba_to_phys_table[ftl->cache_block]; 949 950 951 /* Try to read all unread areas of the cache block*/ 952 for_each_set_bit(sector_num, &ftl->cache_data_invalid_bitmap, 953 ftl->block_size / SM_SECTOR_SIZE) { 954 955 if (!sm_read_sector(ftl, 956 zone_num, block_num, sector_num * SM_SECTOR_SIZE, 957 ftl->cache_data + sector_num * SM_SECTOR_SIZE, NULL)) 958 clear_bit(sector_num, 959 &ftl->cache_data_invalid_bitmap); 960 } 961 restart: 962 963 if (ftl->unstable) 964 return -EIO; 965 966 /* If there are no spare blocks, */ 967 /* we could still continue by erasing/writing the current block, 968 but for such worn out media it doesn't worth the trouble, 969 and the dangers */ 970 if (kfifo_out(&zone->free_sectors, 971 (unsigned char *)&write_sector, 2) != 2) { 972 dbg("no free sectors for write!"); 973 return -EIO; 974 } 975 976 977 if (sm_write_block(ftl, ftl->cache_data, zone_num, write_sector, 978 ftl->cache_block, ftl->cache_data_invalid_bitmap)) 979 goto restart; 980 981 /* Update the FTL table */ 982 zone->lba_to_phys_table[ftl->cache_block] = write_sector; 983 984 /* Write succesfull, so erase and free the old block */ 985 if (block_num > 0) 986 sm_erase_block(ftl, zone_num, block_num, 1); 987 988 sm_cache_init(ftl); 989 return 0; 990 } 991 992 993 /* flush timer, runs a second after last write */ 994 static void sm_cache_flush_timer(unsigned long data) 995 { 996 struct sm_ftl *ftl = (struct sm_ftl *)data; 997 queue_work(cache_flush_workqueue, &ftl->flush_work); 998 } 999 1000 /* cache flush work, kicked by timer */ 1001 static void sm_cache_flush_work(struct work_struct *work) 1002 { 1003 struct sm_ftl *ftl = container_of(work, struct sm_ftl, flush_work); 1004 mutex_lock(&ftl->mutex); 1005 sm_cache_flush(ftl); 1006 mutex_unlock(&ftl->mutex); 1007 return; 1008 } 1009 1010 /* ---------------- outside interface -------------------------------------- */ 1011 1012 /* outside interface: read a sector */ 1013 static int sm_read(struct mtd_blktrans_dev *dev, 1014 unsigned long sect_no, char *buf) 1015 { 1016 struct sm_ftl *ftl = dev->priv; 1017 struct ftl_zone *zone; 1018 int error = 0, in_cache = 0; 1019 int zone_num, block, boffset; 1020 1021 sm_break_offset(ftl, sect_no << 9, &zone_num, &block, &boffset); 1022 mutex_lock(&ftl->mutex); 1023 1024 1025 zone = sm_get_zone(ftl, zone_num); 1026 if (IS_ERR(zone)) { 1027 error = PTR_ERR(zone); 1028 goto unlock; 1029 } 1030 1031 /* Have to look at cache first */ 1032 if (ftl->cache_zone == zone_num && ftl->cache_block == block) { 1033 in_cache = 1; 1034 if (!sm_cache_get(ftl, buf, boffset)) 1035 goto unlock; 1036 } 1037 1038 /* Translate the block and return if doesn't exist in the table */ 1039 block = zone->lba_to_phys_table[block]; 1040 1041 if (block == -1) { 1042 memset(buf, 0xFF, SM_SECTOR_SIZE); 1043 goto unlock; 1044 } 1045 1046 if (sm_read_sector(ftl, zone_num, block, boffset, buf, NULL)) { 1047 error = -EIO; 1048 goto unlock; 1049 } 1050 1051 if (in_cache) 1052 sm_cache_put(ftl, buf, boffset); 1053 unlock: 1054 mutex_unlock(&ftl->mutex); 1055 return error; 1056 } 1057 1058 /* outside interface: write a sector */ 1059 static int sm_write(struct mtd_blktrans_dev *dev, 1060 unsigned long sec_no, char *buf) 1061 { 1062 struct sm_ftl *ftl = dev->priv; 1063 struct ftl_zone *zone; 1064 int error, zone_num, block, boffset; 1065 1066 BUG_ON(ftl->readonly); 1067 sm_break_offset(ftl, sec_no << 9, &zone_num, &block, &boffset); 1068 1069 /* No need in flush thread running now */ 1070 del_timer(&ftl->timer); 1071 mutex_lock(&ftl->mutex); 1072 1073 zone = sm_get_zone(ftl, zone_num); 1074 if (IS_ERR(zone)) { 1075 error = PTR_ERR(zone); 1076 goto unlock; 1077 } 1078 1079 /* If entry is not in cache, flush it */ 1080 if (ftl->cache_block != block || ftl->cache_zone != zone_num) { 1081 1082 error = sm_cache_flush(ftl); 1083 if (error) 1084 goto unlock; 1085 1086 ftl->cache_block = block; 1087 ftl->cache_zone = zone_num; 1088 } 1089 1090 sm_cache_put(ftl, buf, boffset); 1091 unlock: 1092 mod_timer(&ftl->timer, jiffies + msecs_to_jiffies(cache_timeout)); 1093 mutex_unlock(&ftl->mutex); 1094 return error; 1095 } 1096 1097 /* outside interface: flush everything */ 1098 static int sm_flush(struct mtd_blktrans_dev *dev) 1099 { 1100 struct sm_ftl *ftl = dev->priv; 1101 int retval; 1102 1103 mutex_lock(&ftl->mutex); 1104 retval = sm_cache_flush(ftl); 1105 mutex_unlock(&ftl->mutex); 1106 return retval; 1107 } 1108 1109 /* outside interface: device is released */ 1110 static void sm_release(struct mtd_blktrans_dev *dev) 1111 { 1112 struct sm_ftl *ftl = dev->priv; 1113 1114 mutex_lock(&ftl->mutex); 1115 del_timer_sync(&ftl->timer); 1116 cancel_work_sync(&ftl->flush_work); 1117 sm_cache_flush(ftl); 1118 mutex_unlock(&ftl->mutex); 1119 } 1120 1121 /* outside interface: get geometry */ 1122 static int sm_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo) 1123 { 1124 struct sm_ftl *ftl = dev->priv; 1125 geo->heads = ftl->heads; 1126 geo->sectors = ftl->sectors; 1127 geo->cylinders = ftl->cylinders; 1128 return 0; 1129 } 1130 1131 /* external interface: main initialization function */ 1132 static void sm_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd) 1133 { 1134 struct mtd_blktrans_dev *trans; 1135 struct sm_ftl *ftl; 1136 1137 /* Allocate & initialize our private structure */ 1138 ftl = kzalloc(sizeof(struct sm_ftl), GFP_KERNEL); 1139 if (!ftl) 1140 goto error1; 1141 1142 1143 mutex_init(&ftl->mutex); 1144 setup_timer(&ftl->timer, sm_cache_flush_timer, (unsigned long)ftl); 1145 INIT_WORK(&ftl->flush_work, sm_cache_flush_work); 1146 init_completion(&ftl->erase_completion); 1147 1148 /* Read media information */ 1149 if (sm_get_media_info(ftl, mtd)) { 1150 dbg("found unsupported mtd device, aborting"); 1151 goto error2; 1152 } 1153 1154 1155 /* Allocate temporary CIS buffer for read retry support */ 1156 ftl->cis_buffer = kzalloc(SM_SECTOR_SIZE, GFP_KERNEL); 1157 if (!ftl->cis_buffer) 1158 goto error2; 1159 1160 /* Allocate zone array, it will be initialized on demand */ 1161 ftl->zones = kzalloc(sizeof(struct ftl_zone) * ftl->zone_count, 1162 GFP_KERNEL); 1163 if (!ftl->zones) 1164 goto error3; 1165 1166 /* Allocate the cache*/ 1167 ftl->cache_data = kzalloc(ftl->block_size, GFP_KERNEL); 1168 1169 if (!ftl->cache_data) 1170 goto error4; 1171 1172 sm_cache_init(ftl); 1173 1174 1175 /* Allocate upper layer structure and initialize it */ 1176 trans = kzalloc(sizeof(struct mtd_blktrans_dev), GFP_KERNEL); 1177 if (!trans) 1178 goto error5; 1179 1180 ftl->trans = trans; 1181 trans->priv = ftl; 1182 1183 trans->tr = tr; 1184 trans->mtd = mtd; 1185 trans->devnum = -1; 1186 trans->size = (ftl->block_size * ftl->max_lba * ftl->zone_count) >> 9; 1187 trans->readonly = ftl->readonly; 1188 1189 if (sm_find_cis(ftl)) { 1190 dbg("CIS not found on mtd device, aborting"); 1191 goto error6; 1192 } 1193 1194 ftl->disk_attributes = sm_create_sysfs_attributes(ftl); 1195 if (!ftl->disk_attributes) 1196 goto error6; 1197 trans->disk_attributes = ftl->disk_attributes; 1198 1199 sm_printk("Found %d MiB xD/SmartMedia FTL on mtd%d", 1200 (int)(mtd->size / (1024 * 1024)), mtd->index); 1201 1202 dbg("FTL layout:"); 1203 dbg("%d zone(s), each consists of %d blocks (+%d spares)", 1204 ftl->zone_count, ftl->max_lba, 1205 ftl->zone_size - ftl->max_lba); 1206 dbg("each block consists of %d bytes", 1207 ftl->block_size); 1208 1209 1210 /* Register device*/ 1211 if (add_mtd_blktrans_dev(trans)) { 1212 dbg("error in mtdblktrans layer"); 1213 goto error6; 1214 } 1215 return; 1216 error6: 1217 kfree(trans); 1218 error5: 1219 kfree(ftl->cache_data); 1220 error4: 1221 kfree(ftl->zones); 1222 error3: 1223 kfree(ftl->cis_buffer); 1224 error2: 1225 kfree(ftl); 1226 error1: 1227 return; 1228 } 1229 1230 /* main interface: device {surprise,} removal */ 1231 static void sm_remove_dev(struct mtd_blktrans_dev *dev) 1232 { 1233 struct sm_ftl *ftl = dev->priv; 1234 int i; 1235 1236 del_mtd_blktrans_dev(dev); 1237 ftl->trans = NULL; 1238 1239 for (i = 0 ; i < ftl->zone_count; i++) { 1240 1241 if (!ftl->zones[i].initialized) 1242 continue; 1243 1244 kfree(ftl->zones[i].lba_to_phys_table); 1245 kfifo_free(&ftl->zones[i].free_sectors); 1246 } 1247 1248 sm_delete_sysfs_attributes(ftl); 1249 kfree(ftl->cis_buffer); 1250 kfree(ftl->zones); 1251 kfree(ftl->cache_data); 1252 kfree(ftl); 1253 } 1254 1255 static struct mtd_blktrans_ops sm_ftl_ops = { 1256 .name = "smblk", 1257 .major = 0, 1258 .part_bits = SM_FTL_PARTN_BITS, 1259 .blksize = SM_SECTOR_SIZE, 1260 .getgeo = sm_getgeo, 1261 1262 .add_mtd = sm_add_mtd, 1263 .remove_dev = sm_remove_dev, 1264 1265 .readsect = sm_read, 1266 .writesect = sm_write, 1267 1268 .flush = sm_flush, 1269 .release = sm_release, 1270 1271 .owner = THIS_MODULE, 1272 }; 1273 1274 static __init int sm_module_init(void) 1275 { 1276 int error = 0; 1277 1278 cache_flush_workqueue = create_freezable_workqueue("smflush"); 1279 if (!cache_flush_workqueue) 1280 return -ENOMEM; 1281 1282 error = register_mtd_blktrans(&sm_ftl_ops); 1283 if (error) 1284 destroy_workqueue(cache_flush_workqueue); 1285 return error; 1286 1287 } 1288 1289 static void __exit sm_module_exit(void) 1290 { 1291 destroy_workqueue(cache_flush_workqueue); 1292 deregister_mtd_blktrans(&sm_ftl_ops); 1293 } 1294 1295 module_init(sm_module_init); 1296 module_exit(sm_module_exit); 1297 1298 MODULE_LICENSE("GPL"); 1299 MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>"); 1300 MODULE_DESCRIPTION("Smartmedia/xD mtd translation layer"); 1301