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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright © 2009 - Maxim Levitsky4 * SmartMedia/xD translation layer5 */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 22static struct workqueue_struct *cache_flush_workqueue;23 24static int cache_timeout = 1000;25module_param(cache_timeout, int, S_IRUGO);26MODULE_PARM_DESC(cache_timeout,27 "Timeout (in ms) for cache flush (1000 ms default");28 29static int debug;30module_param(debug, int, S_IRUGO | S_IWUSR);31MODULE_PARM_DESC(debug, "Debug level (0-2)");32 33 34/* ------------------- sysfs attributes ---------------------------------- */35struct sm_sysfs_attribute {36 struct device_attribute dev_attr;37 char *data;38 int len;39};40 41static 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 153#define SM_CIS_VENDOR_OFFSET 0x5954static 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;94error4:95 kfree(attributes);96error3:97 kfree(vendor_attribute);98error2:99 kfree(vendor);100error1:101 return NULL;102}103 104static 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 129static 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 block145 * returns -1, if block is erased146 * returns -2 if error happens147 */148static 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 174static 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 */192static 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 */206static 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 217static 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*/237static 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 265again:266 if (try++) {267 /* Avoid infinite recursion on CIS reads, sm_recheck_media268 * won't help anyway269 */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 */282 ret = mtd_read_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops);283 284 /* Test for unknown errors */285 if (ret != 0 && !mtd_is_bitflip_or_eccerr(ret)) {286 dbg("read of block %d at zone %d, failed due to error (%d)",287 block, zone, ret);288 goto again;289 }290 291 /* Do a basic test on the oob, to guard against returned garbage */292 if (oob->reserved != 0xFFFFFFFF && !is_power_of_2(~oob->reserved))293 goto again;294 295 /* This should never happen, unless there is a bug in the mtd driver */296 WARN_ON(ops.oobretlen != SM_OOB_SIZE);297 WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE);298 299 if (!buffer)300 return 0;301 302 /* Test if sector marked as bad */303 if (!sm_sector_valid(oob)) {304 dbg("read of block %d at zone %d, failed because it is marked"305 " as bad" , block, zone);306 goto again;307 }308 309 /* Test ECC*/310 if (mtd_is_eccerr(ret) ||311 (ftl->smallpagenand && sm_correct_sector(buffer, oob))) {312 313 dbg("read of block %d at zone %d, failed due to ECC error",314 block, zone);315 goto again;316 }317 318 return 0;319}320 321/* Writes a sector to media */322static int sm_write_sector(struct sm_ftl *ftl,323 int zone, int block, int boffset,324 uint8_t *buffer, struct sm_oob *oob)325{326 struct mtd_oob_ops ops = { };327 struct mtd_info *mtd = ftl->trans->mtd;328 int ret;329 330 BUG_ON(ftl->readonly);331 332 if (zone == 0 && (block == ftl->cis_block || block == 0)) {333 dbg("attempted to write the CIS!");334 return -EIO;335 }336 337 if (ftl->unstable)338 return -EIO;339 340 ops.mode = ftl->smallpagenand ? MTD_OPS_RAW : MTD_OPS_PLACE_OOB;341 ops.len = SM_SECTOR_SIZE;342 ops.datbuf = buffer;343 ops.ooboffs = 0;344 ops.ooblen = SM_OOB_SIZE;345 ops.oobbuf = (void *)oob;346 347 ret = mtd_write_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops);348 349 /* Now we assume that hardware will catch write bitflip errors */350 351 if (ret) {352 dbg("write to block %d at zone %d, failed with error %d",353 block, zone, ret);354 355 sm_recheck_media(ftl);356 return ret;357 }358 359 /* This should never happen, unless there is a bug in the driver */360 WARN_ON(ops.oobretlen != SM_OOB_SIZE);361 WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE);362 363 return 0;364}365 366/* ------------------------ block IO ------------------------------------- */367 368/* Write a block using data and lba, and invalid sector bitmap */369static int sm_write_block(struct sm_ftl *ftl, uint8_t *buf,370 int zone, int block, int lba,371 unsigned long invalid_bitmap)372{373 bool sm_order = IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC);374 struct sm_oob oob;375 int boffset;376 int retry = 0;377 378 /* Initialize the oob with requested values */379 memset(&oob, 0xFF, SM_OOB_SIZE);380 sm_write_lba(&oob, lba);381restart:382 if (ftl->unstable)383 return -EIO;384 385 for (boffset = 0; boffset < ftl->block_size;386 boffset += SM_SECTOR_SIZE) {387 388 oob.data_status = 0xFF;389 390 if (test_bit(boffset / SM_SECTOR_SIZE, &invalid_bitmap)) {391 392 sm_printk("sector %d of block at LBA %d of zone %d"393 " couldn't be read, marking it as invalid",394 boffset / SM_SECTOR_SIZE, lba, zone);395 396 oob.data_status = 0;397 }398 399 if (ftl->smallpagenand) {400 ecc_sw_hamming_calculate(buf + boffset,401 SM_SMALL_PAGE, oob.ecc1,402 sm_order);403 404 ecc_sw_hamming_calculate(buf + boffset + SM_SMALL_PAGE,405 SM_SMALL_PAGE, oob.ecc2,406 sm_order);407 }408 if (!sm_write_sector(ftl, zone, block, boffset,409 buf + boffset, &oob))410 continue;411 412 if (!retry) {413 414 /* If write fails. try to erase the block */415 /* This is safe, because we never write in blocks416 * that contain valuable data.417 * This is intended to repair block that are marked418 * as erased, but that isn't fully erased419 */420 421 if (sm_erase_block(ftl, zone, block, 0))422 return -EIO;423 424 retry = 1;425 goto restart;426 } else {427 sm_mark_block_bad(ftl, zone, block);428 return -EIO;429 }430 }431 return 0;432}433 434 435/* Mark whole block at offset 'offs' as bad. */436static void sm_mark_block_bad(struct sm_ftl *ftl, int zone, int block)437{438 struct sm_oob oob;439 int boffset;440 441 memset(&oob, 0xFF, SM_OOB_SIZE);442 oob.block_status = 0xF0;443 444 if (ftl->unstable)445 return;446 447 if (sm_recheck_media(ftl))448 return;449 450 sm_printk("marking block %d of zone %d as bad", block, zone);451 452 /* We aren't checking the return value, because we don't care */453 /* This also fails on fake xD cards, but I guess these won't expose454 * any bad blocks till fail completely455 */456 for (boffset = 0; boffset < ftl->block_size; boffset += SM_SECTOR_SIZE)457 sm_write_sector(ftl, zone, block, boffset, NULL, &oob);458}459 460/*461 * Erase a block within a zone462 * If erase succeeds, it updates free block fifo, otherwise marks block as bad463 */464static int sm_erase_block(struct sm_ftl *ftl, int zone_num, uint16_t block,465 int put_free)466{467 struct ftl_zone *zone = &ftl->zones[zone_num];468 struct mtd_info *mtd = ftl->trans->mtd;469 struct erase_info erase;470 471 erase.addr = sm_mkoffset(ftl, zone_num, block, 0);472 erase.len = ftl->block_size;473 474 if (ftl->unstable)475 return -EIO;476 477 BUG_ON(ftl->readonly);478 479 if (zone_num == 0 && (block == ftl->cis_block || block == 0)) {480 sm_printk("attempted to erase the CIS!");481 return -EIO;482 }483 484 if (mtd_erase(mtd, &erase)) {485 sm_printk("erase of block %d in zone %d failed",486 block, zone_num);487 goto error;488 }489 490 if (put_free)491 kfifo_in(&zone->free_sectors,492 (const unsigned char *)&block, sizeof(block));493 494 return 0;495error:496 sm_mark_block_bad(ftl, zone_num, block);497 return -EIO;498}499 500/* Thoroughly test that block is valid. */501static int sm_check_block(struct sm_ftl *ftl, int zone, int block)502{503 int boffset;504 struct sm_oob oob;505 int lbas[] = { -3, 0, 0, 0 };506 int i = 0;507 int test_lba;508 509 510 /* First just check that block doesn't look fishy */511 /* Only blocks that are valid or are sliced in two parts, are512 * accepted513 */514 for (boffset = 0; boffset < ftl->block_size;515 boffset += SM_SECTOR_SIZE) {516 517 /* This shouldn't happen anyway */518 if (sm_read_sector(ftl, zone, block, boffset, NULL, &oob))519 return -2;520 521 test_lba = sm_read_lba(&oob);522 523 if (lbas[i] != test_lba)524 lbas[++i] = test_lba;525 526 /* If we found three different LBAs, something is fishy */527 if (i == 3)528 return -EIO;529 }530 531 /* If the block is sliced (partially erased usually) erase it */532 if (i == 2) {533 sm_erase_block(ftl, zone, block, 1);534 return 1;535 }536 537 return 0;538}539 540/* ----------------- media scanning --------------------------------- */541static const struct chs_entry chs_table[] = {542 { 1, 125, 4, 4 },543 { 2, 125, 4, 8 },544 { 4, 250, 4, 8 },545 { 8, 250, 4, 16 },546 { 16, 500, 4, 16 },547 { 32, 500, 8, 16 },548 { 64, 500, 8, 32 },549 { 128, 500, 16, 32 },550 { 256, 1000, 16, 32 },551 { 512, 1015, 32, 63 },552 { 1024, 985, 33, 63 },553 { 2048, 985, 33, 63 },554 { 0 },555};556 557 558static const uint8_t cis_signature[] = {559 0x01, 0x03, 0xD9, 0x01, 0xFF, 0x18, 0x02, 0xDF, 0x01, 0x20560};561/* Find out media parameters.562 * This ideally has to be based on nand id, but for now device size is enough563 */564static int sm_get_media_info(struct sm_ftl *ftl, struct mtd_info *mtd)565{566 int i;567 int size_in_megs = mtd->size / (1024 * 1024);568 569 ftl->readonly = mtd->type == MTD_ROM;570 571 /* Manual settings for very old devices */572 ftl->zone_count = 1;573 ftl->smallpagenand = 0;574 575 switch (size_in_megs) {576 case 1:577 /* 1 MiB flash/rom SmartMedia card (256 byte pages)*/578 ftl->zone_size = 256;579 ftl->max_lba = 250;580 ftl->block_size = 8 * SM_SECTOR_SIZE;581 ftl->smallpagenand = 1;582 583 break;584 case 2:585 /* 2 MiB flash SmartMedia (256 byte pages)*/586 if (mtd->writesize == SM_SMALL_PAGE) {587 ftl->zone_size = 512;588 ftl->max_lba = 500;589 ftl->block_size = 8 * SM_SECTOR_SIZE;590 ftl->smallpagenand = 1;591 /* 2 MiB rom SmartMedia */592 } else {593 594 if (!ftl->readonly)595 return -ENODEV;596 597 ftl->zone_size = 256;598 ftl->max_lba = 250;599 ftl->block_size = 16 * SM_SECTOR_SIZE;600 }601 break;602 case 4:603 /* 4 MiB flash/rom SmartMedia device */604 ftl->zone_size = 512;605 ftl->max_lba = 500;606 ftl->block_size = 16 * SM_SECTOR_SIZE;607 break;608 case 8:609 /* 8 MiB flash/rom SmartMedia device */610 ftl->zone_size = 1024;611 ftl->max_lba = 1000;612 ftl->block_size = 16 * SM_SECTOR_SIZE;613 }614 615 /* Minimum xD size is 16MiB. Also, all xD cards have standard zone616 * sizes. SmartMedia cards exist up to 128 MiB and have same layout617 */618 if (size_in_megs >= 16) {619 ftl->zone_count = size_in_megs / 16;620 ftl->zone_size = 1024;621 ftl->max_lba = 1000;622 ftl->block_size = 32 * SM_SECTOR_SIZE;623 }624 625 /* Test for proper write,erase and oob sizes */626 if (mtd->erasesize > ftl->block_size)627 return -ENODEV;628 629 if (mtd->writesize > SM_SECTOR_SIZE)630 return -ENODEV;631 632 if (ftl->smallpagenand && mtd->oobsize < SM_SMALL_OOB_SIZE)633 return -ENODEV;634 635 if (!ftl->smallpagenand && mtd->oobsize < SM_OOB_SIZE)636 return -ENODEV;637 638 /* We use OOB */639 if (!mtd_has_oob(mtd))640 return -ENODEV;641 642 /* Find geometry information */643 for (i = 0 ; i < ARRAY_SIZE(chs_table) ; i++) {644 if (chs_table[i].size == size_in_megs) {645 ftl->cylinders = chs_table[i].cyl;646 ftl->heads = chs_table[i].head;647 ftl->sectors = chs_table[i].sec;648 return 0;649 }650 }651 652 sm_printk("media has unknown size : %dMiB", size_in_megs);653 ftl->cylinders = 985;654 ftl->heads = 33;655 ftl->sectors = 63;656 return 0;657}658 659/* Validate the CIS */660static int sm_read_cis(struct sm_ftl *ftl)661{662 struct sm_oob oob;663 664 if (sm_read_sector(ftl,665 0, ftl->cis_block, ftl->cis_boffset, ftl->cis_buffer, &oob))666 return -EIO;667 668 if (!sm_sector_valid(&oob) || !sm_block_valid(&oob))669 return -EIO;670 671 if (!memcmp(ftl->cis_buffer + ftl->cis_page_offset,672 cis_signature, sizeof(cis_signature))) {673 return 0;674 }675 676 return -EIO;677}678 679/* Scan the media for the CIS */680static int sm_find_cis(struct sm_ftl *ftl)681{682 struct sm_oob oob;683 int block, boffset;684 int block_found = 0;685 int cis_found = 0;686 687 /* Search for first valid block */688 for (block = 0 ; block < ftl->zone_size - ftl->max_lba ; block++) {689 690 if (sm_read_sector(ftl, 0, block, 0, NULL, &oob))691 continue;692 693 if (!sm_block_valid(&oob))694 continue;695 block_found = 1;696 break;697 }698 699 if (!block_found)700 return -EIO;701 702 /* Search for first valid sector in this block */703 for (boffset = 0 ; boffset < ftl->block_size;704 boffset += SM_SECTOR_SIZE) {705 706 if (sm_read_sector(ftl, 0, block, boffset, NULL, &oob))707 continue;708 709 if (!sm_sector_valid(&oob))710 continue;711 break;712 }713 714 if (boffset == ftl->block_size)715 return -EIO;716 717 ftl->cis_block = block;718 ftl->cis_boffset = boffset;719 ftl->cis_page_offset = 0;720 721 cis_found = !sm_read_cis(ftl);722 723 if (!cis_found) {724 ftl->cis_page_offset = SM_SMALL_PAGE;725 cis_found = !sm_read_cis(ftl);726 }727 728 if (cis_found) {729 dbg("CIS block found at offset %x",730 block * ftl->block_size +731 boffset + ftl->cis_page_offset);732 return 0;733 }734 return -EIO;735}736 737/* Basic test to determine if underlying mtd device if functional */738static int sm_recheck_media(struct sm_ftl *ftl)739{740 if (sm_read_cis(ftl)) {741 742 if (!ftl->unstable) {743 sm_printk("media unstable, not allowing writes");744 ftl->unstable = 1;745 }746 return -EIO;747 }748 return 0;749}750 751/* Initialize a FTL zone */752static int sm_init_zone(struct sm_ftl *ftl, int zone_num)753{754 struct ftl_zone *zone = &ftl->zones[zone_num];755 struct sm_oob oob;756 uint16_t block;757 int lba;758 int i = 0;759 int len;760 761 dbg("initializing zone %d", zone_num);762 763 /* Allocate memory for FTL table */764 zone->lba_to_phys_table = kmalloc_array(ftl->max_lba, 2, GFP_KERNEL);765 766 if (!zone->lba_to_phys_table)767 return -ENOMEM;768 memset(zone->lba_to_phys_table, -1, ftl->max_lba * 2);769 770 771 /* Allocate memory for free sectors FIFO */772 if (kfifo_alloc(&zone->free_sectors, ftl->zone_size * 2, GFP_KERNEL)) {773 kfree(zone->lba_to_phys_table);774 return -ENOMEM;775 }776 777 /* Now scan the zone */778 for (block = 0 ; block < ftl->zone_size ; block++) {779 780 /* Skip blocks till the CIS (including) */781 if (zone_num == 0 && block <= ftl->cis_block)782 continue;783 784 /* Read the oob of first sector */785 if (sm_read_sector(ftl, zone_num, block, 0, NULL, &oob)) {786 kfifo_free(&zone->free_sectors);787 kfree(zone->lba_to_phys_table);788 return -EIO;789 }790 791 /* Test to see if block is erased. It is enough to test792 * first sector, because erase happens in one shot793 */794 if (sm_block_erased(&oob)) {795 kfifo_in(&zone->free_sectors,796 (unsigned char *)&block, 2);797 continue;798 }799 800 /* If block is marked as bad, skip it */801 /* This assumes we can trust first sector*/802 /* However the way the block valid status is defined, ensures803 * very low probability of failure here804 */805 if (!sm_block_valid(&oob)) {806 dbg("PH %04d <-> <marked bad>", block);807 continue;808 }809 810 811 lba = sm_read_lba(&oob);812 813 /* Invalid LBA means that block is damaged. */814 /* We can try to erase it, or mark it as bad, but815 * lets leave that to recovery application816 */817 if (lba == -2 || lba >= ftl->max_lba) {818 dbg("PH %04d <-> LBA %04d(bad)", block, lba);819 continue;820 }821 822 823 /* If there is no collision,824 * just put the sector in the FTL table825 */826 if (zone->lba_to_phys_table[lba] < 0) {827 dbg_verbose("PH %04d <-> LBA %04d", block, lba);828 zone->lba_to_phys_table[lba] = block;829 continue;830 }831 832 sm_printk("collision"833 " of LBA %d between blocks %d and %d in zone %d",834 lba, zone->lba_to_phys_table[lba], block, zone_num);835 836 /* Test that this block is valid*/837 if (sm_check_block(ftl, zone_num, block))838 continue;839 840 /* Test now the old block */841 if (sm_check_block(ftl, zone_num,842 zone->lba_to_phys_table[lba])) {843 zone->lba_to_phys_table[lba] = block;844 continue;845 }846 847 /* If both blocks are valid and share same LBA, it means that848 * they hold different versions of same data. It not849 * known which is more recent, thus just erase one of them850 */851 sm_printk("both blocks are valid, erasing the later");852 sm_erase_block(ftl, zone_num, block, 1);853 }854 855 dbg("zone initialized");856 zone->initialized = 1;857 858 /* No free sectors, means that the zone is heavily damaged, write won't859 * work, but it can still can be (partially) read860 */861 if (!kfifo_len(&zone->free_sectors)) {862 sm_printk("no free blocks in zone %d", zone_num);863 return 0;864 }865 866 /* Randomize first block we write to */867 get_random_bytes(&i, 2);868 i %= (kfifo_len(&zone->free_sectors) / 2);869 870 while (i--) {871 len = kfifo_out(&zone->free_sectors,872 (unsigned char *)&block, 2);873 WARN_ON(len != 2);874 kfifo_in(&zone->free_sectors, (const unsigned char *)&block, 2);875 }876 return 0;877}878 879/* Get and automatically initialize an FTL mapping for one zone */880static struct ftl_zone *sm_get_zone(struct sm_ftl *ftl, int zone_num)881{882 struct ftl_zone *zone;883 int error;884 885 BUG_ON(zone_num >= ftl->zone_count);886 zone = &ftl->zones[zone_num];887 888 if (!zone->initialized) {889 error = sm_init_zone(ftl, zone_num);890 891 if (error)892 return ERR_PTR(error);893 }894 return zone;895}896 897 898/* ----------------- cache handling ------------------------------------------*/899 900/* Initialize the one block cache */901static void sm_cache_init(struct sm_ftl *ftl)902{903 ftl->cache_data_invalid_bitmap = 0xFFFFFFFF;904 ftl->cache_clean = 1;905 ftl->cache_zone = -1;906 ftl->cache_block = -1;907 /*memset(ftl->cache_data, 0xAA, ftl->block_size);*/908}909 910/* Put sector in one block cache */911static void sm_cache_put(struct sm_ftl *ftl, char *buffer, int boffset)912{913 memcpy(ftl->cache_data + boffset, buffer, SM_SECTOR_SIZE);914 clear_bit(boffset / SM_SECTOR_SIZE, &ftl->cache_data_invalid_bitmap);915 ftl->cache_clean = 0;916}917 918/* Read a sector from the cache */919static int sm_cache_get(struct sm_ftl *ftl, char *buffer, int boffset)920{921 if (test_bit(boffset / SM_SECTOR_SIZE,922 &ftl->cache_data_invalid_bitmap))923 return -1;924 925 memcpy(buffer, ftl->cache_data + boffset, SM_SECTOR_SIZE);926 return 0;927}928 929/* Write the cache to hardware */930static int sm_cache_flush(struct sm_ftl *ftl)931{932 struct ftl_zone *zone;933 934 int sector_num;935 uint16_t write_sector;936 int zone_num = ftl->cache_zone;937 int block_num;938 939 if (ftl->cache_clean)940 return 0;941 942 if (ftl->unstable)943 return -EIO;944 945 BUG_ON(zone_num < 0);946 zone = &ftl->zones[zone_num];947 block_num = zone->lba_to_phys_table[ftl->cache_block];948 949 950 /* Try to read all unread areas of the cache block*/951 for_each_set_bit(sector_num, &ftl->cache_data_invalid_bitmap,952 ftl->block_size / SM_SECTOR_SIZE) {953 954 if (!sm_read_sector(ftl,955 zone_num, block_num, sector_num * SM_SECTOR_SIZE,956 ftl->cache_data + sector_num * SM_SECTOR_SIZE, NULL))957 clear_bit(sector_num,958 &ftl->cache_data_invalid_bitmap);959 }960restart:961 962 if (ftl->unstable)963 return -EIO;964 965 /* If there are no spare blocks, */966 /* we could still continue by erasing/writing the current block,967 * but for such worn out media it doesn't worth the trouble,968 * and the dangers969 */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 successful, 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 */994static void sm_cache_flush_timer(struct timer_list *t)995{996 struct sm_ftl *ftl = from_timer(ftl, t, timer);997 queue_work(cache_flush_workqueue, &ftl->flush_work);998}999 1000/* cache flush work, kicked by timer */1001static 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 */1013static 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);1053unlock:1054 mutex_unlock(&ftl->mutex);1055 return error;1056}1057 1058/* outside interface: write a sector */1059static 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 = 0, 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);1091unlock: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 */1098static 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 */1110static void sm_release(struct mtd_blktrans_dev *dev)1111{1112 struct sm_ftl *ftl = dev->priv;1113 1114 del_timer_sync(&ftl->timer);1115 cancel_work_sync(&ftl->flush_work);1116 mutex_lock(&ftl->mutex);1117 sm_cache_flush(ftl);1118 mutex_unlock(&ftl->mutex);1119}1120 1121/* outside interface: get geometry */1122static 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 */1132static 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 timer_setup(&ftl->timer, sm_cache_flush_timer, 0);1145 INIT_WORK(&ftl->flush_work, sm_cache_flush_work);1146 1147 /* Read media information */1148 if (sm_get_media_info(ftl, mtd)) {1149 dbg("found unsupported mtd device, aborting");1150 goto error2;1151 }1152 1153 1154 /* Allocate temporary CIS buffer for read retry support */1155 ftl->cis_buffer = kzalloc(SM_SECTOR_SIZE, GFP_KERNEL);1156 if (!ftl->cis_buffer)1157 goto error2;1158 1159 /* Allocate zone array, it will be initialized on demand */1160 ftl->zones = kcalloc(ftl->zone_count, sizeof(struct ftl_zone),1161 GFP_KERNEL);1162 if (!ftl->zones)1163 goto error3;1164 1165 /* Allocate the cache*/1166 ftl->cache_data = kzalloc(ftl->block_size, GFP_KERNEL);1167 1168 if (!ftl->cache_data)1169 goto error4;1170 1171 sm_cache_init(ftl);1172 1173 1174 /* Allocate upper layer structure and initialize it */1175 trans = kzalloc(sizeof(struct mtd_blktrans_dev), GFP_KERNEL);1176 if (!trans)1177 goto error5;1178 1179 ftl->trans = trans;1180 trans->priv = ftl;1181 1182 trans->tr = tr;1183 trans->mtd = mtd;1184 trans->devnum = -1;1185 trans->size = (ftl->block_size * ftl->max_lba * ftl->zone_count) >> 9;1186 trans->readonly = ftl->readonly;1187 1188 if (sm_find_cis(ftl)) {1189 dbg("CIS not found on mtd device, aborting");1190 goto error6;1191 }1192 1193 ftl->disk_attributes = sm_create_sysfs_attributes(ftl);1194 if (!ftl->disk_attributes)1195 goto error6;1196 trans->disk_attributes = ftl->disk_attributes;1197 1198 sm_printk("Found %d MiB xD/SmartMedia FTL on mtd%d",1199 (int)(mtd->size / (1024 * 1024)), mtd->index);1200 1201 dbg("FTL layout:");1202 dbg("%d zone(s), each consists of %d blocks (+%d spares)",1203 ftl->zone_count, ftl->max_lba,1204 ftl->zone_size - ftl->max_lba);1205 dbg("each block consists of %d bytes",1206 ftl->block_size);1207 1208 1209 /* Register device*/1210 if (add_mtd_blktrans_dev(trans)) {1211 dbg("error in mtdblktrans layer");1212 goto error6;1213 }1214 return;1215error6:1216 kfree(trans);1217error5:1218 kfree(ftl->cache_data);1219error4:1220 kfree(ftl->zones);1221error3:1222 kfree(ftl->cis_buffer);1223error2:1224 kfree(ftl);1225error1:1226 return;1227}1228 1229/* main interface: device {surprise,} removal */1230static void sm_remove_dev(struct mtd_blktrans_dev *dev)1231{1232 struct sm_ftl *ftl = dev->priv;1233 int i;1234 1235 del_mtd_blktrans_dev(dev);1236 ftl->trans = NULL;1237 1238 for (i = 0 ; i < ftl->zone_count; i++) {1239 1240 if (!ftl->zones[i].initialized)1241 continue;1242 1243 kfree(ftl->zones[i].lba_to_phys_table);1244 kfifo_free(&ftl->zones[i].free_sectors);1245 }1246 1247 sm_delete_sysfs_attributes(ftl);1248 kfree(ftl->cis_buffer);1249 kfree(ftl->zones);1250 kfree(ftl->cache_data);1251 kfree(ftl);1252}1253 1254static struct mtd_blktrans_ops sm_ftl_ops = {1255 .name = "smblk",1256 .major = 0,1257 .part_bits = SM_FTL_PARTN_BITS,1258 .blksize = SM_SECTOR_SIZE,1259 .getgeo = sm_getgeo,1260 1261 .add_mtd = sm_add_mtd,1262 .remove_dev = sm_remove_dev,1263 1264 .readsect = sm_read,1265 .writesect = sm_write,1266 1267 .flush = sm_flush,1268 .release = sm_release,1269 1270 .owner = THIS_MODULE,1271};1272 1273static __init int sm_module_init(void)1274{1275 int error = 0;1276 1277 cache_flush_workqueue = create_freezable_workqueue("smflush");1278 if (!cache_flush_workqueue)1279 return -ENOMEM;1280 1281 error = register_mtd_blktrans(&sm_ftl_ops);1282 if (error)1283 destroy_workqueue(cache_flush_workqueue);1284 return error;1285 1286}1287 1288static void __exit sm_module_exit(void)1289{1290 destroy_workqueue(cache_flush_workqueue);1291 deregister_mtd_blktrans(&sm_ftl_ops);1292}1293 1294module_init(sm_module_init);1295module_exit(sm_module_exit);1296 1297MODULE_LICENSE("GPL");1298MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");1299MODULE_DESCRIPTION("Smartmedia/xD mtd translation layer");1300