// SPDX-License-Identifier: GPL-2.0-only /* * Copyright © 2009 - Maxim Levitsky * SmartMedia/xD translation layer */ #include #include #include #include #include #include #include #include #include #include #include "nand/raw/sm_common.h" #include "sm_ftl.h" static struct workqueue_struct *cache_flush_workqueue; static int cache_timeout = 1000; module_param(cache_timeout, int, S_IRUGO); MODULE_PARM_DESC(cache_timeout, "Timeout (in ms) for cache flush (1000 ms default"); static int debug; module_param(debug, int, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(debug, "Debug level (0-2)"); /* ------------------- sysfs attributes ---------------------------------- */ struct sm_sysfs_attribute { struct device_attribute dev_attr; char *data; int len; }; static ssize_t sm_attr_show(struct device *dev, struct device_attribute *attr, char *buf) { struct sm_sysfs_attribute *sm_attr = container_of(attr, struct sm_sysfs_attribute, dev_attr); strncpy(buf, sm_attr->data, sm_attr->len); return sm_attr->len; } #define NUM_ATTRIBUTES 1 #define SM_CIS_VENDOR_OFFSET 0x59 static struct attribute_group *sm_create_sysfs_attributes(struct sm_ftl *ftl) { struct attribute_group *attr_group; struct attribute **attributes; struct sm_sysfs_attribute *vendor_attribute; char *vendor; vendor = kstrndup(ftl->cis_buffer + SM_CIS_VENDOR_OFFSET, SM_SMALL_PAGE - SM_CIS_VENDOR_OFFSET, GFP_KERNEL); if (!vendor) goto error1; /* Initialize sysfs attributes */ vendor_attribute = kzalloc(sizeof(struct sm_sysfs_attribute), GFP_KERNEL); if (!vendor_attribute) goto error2; sysfs_attr_init(&vendor_attribute->dev_attr.attr); vendor_attribute->data = vendor; vendor_attribute->len = strlen(vendor); vendor_attribute->dev_attr.attr.name = "vendor"; vendor_attribute->dev_attr.attr.mode = S_IRUGO; vendor_attribute->dev_attr.show = sm_attr_show; /* Create array of pointers to the attributes */ attributes = kcalloc(NUM_ATTRIBUTES + 1, sizeof(struct attribute *), GFP_KERNEL); if (!attributes) goto error3; attributes[0] = &vendor_attribute->dev_attr.attr; /* Finally create the attribute group */ attr_group = kzalloc(sizeof(struct attribute_group), GFP_KERNEL); if (!attr_group) goto error4; attr_group->attrs = attributes; return attr_group; error4: kfree(attributes); error3: kfree(vendor_attribute); error2: kfree(vendor); error1: return NULL; } static void sm_delete_sysfs_attributes(struct sm_ftl *ftl) { struct attribute **attributes = ftl->disk_attributes->attrs; int i; for (i = 0; attributes[i] ; i++) { struct device_attribute *dev_attr = container_of(attributes[i], struct device_attribute, attr); struct sm_sysfs_attribute *sm_attr = container_of(dev_attr, struct sm_sysfs_attribute, dev_attr); kfree(sm_attr->data); kfree(sm_attr); } kfree(ftl->disk_attributes->attrs); kfree(ftl->disk_attributes); } /* ----------------------- oob helpers -------------------------------------- */ static int sm_get_lba(uint8_t *lba) { /* check fixed bits */ if ((lba[0] & 0xF8) != 0x10) return -2; /* check parity - endianness doesn't matter */ if (hweight16(*(uint16_t *)lba) & 1) return -2; return (lba[1] >> 1) | ((lba[0] & 0x07) << 7); } /* * Read LBA associated with block * returns -1, if block is erased * returns -2 if error happens */ static int sm_read_lba(struct sm_oob *oob) { static const uint32_t erased_pattern[4] = { 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF }; uint16_t lba_test; int lba; /* First test for erased block */ if (!memcmp(oob, erased_pattern, SM_OOB_SIZE)) return -1; /* Now check is both copies of the LBA differ too much */ lba_test = *(uint16_t *)oob->lba_copy1 ^ *(uint16_t*)oob->lba_copy2; if (lba_test && !is_power_of_2(lba_test)) return -2; /* And read it */ lba = sm_get_lba(oob->lba_copy1); if (lba == -2) lba = sm_get_lba(oob->lba_copy2); return lba; } static void sm_write_lba(struct sm_oob *oob, uint16_t lba) { uint8_t tmp[2]; WARN_ON(lba >= 1000); tmp[0] = 0x10 | ((lba >> 7) & 0x07); tmp[1] = (lba << 1) & 0xFF; if (hweight16(*(uint16_t *)tmp) & 0x01) tmp[1] |= 1; oob->lba_copy1[0] = oob->lba_copy2[0] = tmp[0]; oob->lba_copy1[1] = oob->lba_copy2[1] = tmp[1]; } /* Make offset from parts */ static loff_t sm_mkoffset(struct sm_ftl *ftl, int zone, int block, int boffset) { WARN_ON(boffset & (SM_SECTOR_SIZE - 1)); WARN_ON(zone < 0 || zone >= ftl->zone_count); WARN_ON(block >= ftl->zone_size); WARN_ON(boffset >= ftl->block_size); if (block == -1) return -1; return (zone * SM_MAX_ZONE_SIZE + block) * ftl->block_size + boffset; } /* Breaks offset into parts */ static void sm_break_offset(struct sm_ftl *ftl, loff_t loffset, int *zone, int *block, int *boffset) { u64 offset = loffset; *boffset = do_div(offset, ftl->block_size); *block = do_div(offset, ftl->max_lba); *zone = offset >= ftl->zone_count ? -1 : offset; } /* ---------------------- low level IO ------------------------------------- */ static int sm_correct_sector(uint8_t *buffer, struct sm_oob *oob) { bool sm_order = IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC); uint8_t ecc[3]; ecc_sw_hamming_calculate(buffer, SM_SMALL_PAGE, ecc, sm_order); if (ecc_sw_hamming_correct(buffer, ecc, oob->ecc1, SM_SMALL_PAGE, sm_order) < 0) return -EIO; buffer += SM_SMALL_PAGE; ecc_sw_hamming_calculate(buffer, SM_SMALL_PAGE, ecc, sm_order); if (ecc_sw_hamming_correct(buffer, ecc, oob->ecc2, SM_SMALL_PAGE, sm_order) < 0) return -EIO; return 0; } /* Reads a sector + oob*/ static int sm_read_sector(struct sm_ftl *ftl, int zone, int block, int boffset, uint8_t *buffer, struct sm_oob *oob) { struct mtd_info *mtd = ftl->trans->mtd; struct mtd_oob_ops ops = { }; struct sm_oob tmp_oob; int ret = -EIO; int try = 0; /* FTL can contain -1 entries that are by default filled with bits */ if (block == -1) { if (buffer) memset(buffer, 0xFF, SM_SECTOR_SIZE); return 0; } /* User might not need the oob, but we do for data verification */ if (!oob) oob = &tmp_oob; ops.mode = ftl->smallpagenand ? MTD_OPS_RAW : MTD_OPS_PLACE_OOB; ops.ooboffs = 0; ops.ooblen = SM_OOB_SIZE; ops.oobbuf = (void *)oob; ops.len = SM_SECTOR_SIZE; ops.datbuf = buffer; again: if (try++) { /* Avoid infinite recursion on CIS reads, sm_recheck_media * won't help anyway */ if (zone == 0 && block == ftl->cis_block && boffset == ftl->cis_boffset) return ret; /* Test if media is stable */ if (try == 3 || sm_recheck_media(ftl)) return ret; } /* Unfortunately, oob read will _always_ succeed, * despite card removal..... */ ret = mtd_read_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops); /* Test for unknown errors */ if (ret != 0 && !mtd_is_bitflip_or_eccerr(ret)) { dbg("read of block %d at zone %d, failed due to error (%d)", block, zone, ret); goto again; } /* Do a basic test on the oob, to guard against returned garbage */ if (oob->reserved != 0xFFFFFFFF && !is_power_of_2(~oob->reserved)) goto again; /* This should never happen, unless there is a bug in the mtd driver */ WARN_ON(ops.oobretlen != SM_OOB_SIZE); WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE); if (!buffer) return 0; /* Test if sector marked as bad */ if (!sm_sector_valid(oob)) { dbg("read of block %d at zone %d, failed because it is marked" " as bad" , block, zone); goto again; } /* Test ECC*/ if (mtd_is_eccerr(ret) || (ftl->smallpagenand && sm_correct_sector(buffer, oob))) { dbg("read of block %d at zone %d, failed due to ECC error", block, zone); goto again; } return 0; } /* Writes a sector to media */ static int sm_write_sector(struct sm_ftl *ftl, int zone, int block, int boffset, uint8_t *buffer, struct sm_oob *oob) { struct mtd_oob_ops ops = { }; struct mtd_info *mtd = ftl->trans->mtd; int ret; BUG_ON(ftl->readonly); if (zone == 0 && (block == ftl->cis_block || block == 0)) { dbg("attempted to write the CIS!"); return -EIO; } if (ftl->unstable) return -EIO; ops.mode = ftl->smallpagenand ? MTD_OPS_RAW : MTD_OPS_PLACE_OOB; ops.len = SM_SECTOR_SIZE; ops.datbuf = buffer; ops.ooboffs = 0; ops.ooblen = SM_OOB_SIZE; ops.oobbuf = (void *)oob; ret = mtd_write_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops); /* Now we assume that hardware will catch write bitflip errors */ if (ret) { dbg("write to block %d at zone %d, failed with error %d", block, zone, ret); sm_recheck_media(ftl); return ret; } /* This should never happen, unless there is a bug in the driver */ WARN_ON(ops.oobretlen != SM_OOB_SIZE); WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE); return 0; } /* ------------------------ block IO ------------------------------------- */ /* Write a block using data and lba, and invalid sector bitmap */ static int sm_write_block(struct sm_ftl *ftl, uint8_t *buf, int zone, int block, int lba, unsigned long invalid_bitmap) { bool sm_order = IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC); struct sm_oob oob; int boffset; int retry = 0; /* Initialize the oob with requested values */ memset(&oob, 0xFF, SM_OOB_SIZE); sm_write_lba(&oob, lba); restart: if (ftl->unstable) return -EIO; for (boffset = 0; boffset < ftl->block_size; boffset += SM_SECTOR_SIZE) { oob.data_status = 0xFF; if (test_bit(boffset / SM_SECTOR_SIZE, &invalid_bitmap)) { sm_printk("sector %d of block at LBA %d of zone %d" " couldn't be read, marking it as invalid", boffset / SM_SECTOR_SIZE, lba, zone); oob.data_status = 0; } if (ftl->smallpagenand) { ecc_sw_hamming_calculate(buf + boffset, SM_SMALL_PAGE, oob.ecc1, sm_order); ecc_sw_hamming_calculate(buf + boffset + SM_SMALL_PAGE, SM_SMALL_PAGE, oob.ecc2, sm_order); } if (!sm_write_sector(ftl, zone, block, boffset, buf + boffset, &oob)) continue; if (!retry) { /* If write fails. try to erase the block */ /* This is safe, because we never write in blocks * that contain valuable data. * This is intended to repair block that are marked * as erased, but that isn't fully erased */ if (sm_erase_block(ftl, zone, block, 0)) return -EIO; retry = 1; goto restart; } else { sm_mark_block_bad(ftl, zone, block); return -EIO; } } return 0; } /* Mark whole block at offset 'offs' as bad. */ static void sm_mark_block_bad(struct sm_ftl *ftl, int zone, int block) { struct sm_oob oob; int boffset; memset(&oob, 0xFF, SM_OOB_SIZE); oob.block_status = 0xF0; if (ftl->unstable) return; if (sm_recheck_media(ftl)) return; sm_printk("marking block %d of zone %d as bad", block, zone); /* We aren't checking the return value, because we don't care */ /* This also fails on fake xD cards, but I guess these won't expose * any bad blocks till fail completely */ for (boffset = 0; boffset < ftl->block_size; boffset += SM_SECTOR_SIZE) sm_write_sector(ftl, zone, block, boffset, NULL, &oob); } /* * Erase a block within a zone * If erase succeeds, it updates free block fifo, otherwise marks block as bad */ static int sm_erase_block(struct sm_ftl *ftl, int zone_num, uint16_t block, int put_free) { struct ftl_zone *zone = &ftl->zones[zone_num]; struct mtd_info *mtd = ftl->trans->mtd; struct erase_info erase; erase.addr = sm_mkoffset(ftl, zone_num, block, 0); erase.len = ftl->block_size; if (ftl->unstable) return -EIO; BUG_ON(ftl->readonly); if (zone_num == 0 && (block == ftl->cis_block || block == 0)) { sm_printk("attempted to erase the CIS!"); return -EIO; } if (mtd_erase(mtd, &erase)) { sm_printk("erase of block %d in zone %d failed", block, zone_num); goto error; } if (put_free) kfifo_in(&zone->free_sectors, (const unsigned char *)&block, sizeof(block)); return 0; error: sm_mark_block_bad(ftl, zone_num, block); return -EIO; } /* Thoroughly test that block is valid. */ static int sm_check_block(struct sm_ftl *ftl, int zone, int block) { int boffset; struct sm_oob oob; int lbas[] = { -3, 0, 0, 0 }; int i = 0; int test_lba; /* First just check that block doesn't look fishy */ /* Only blocks that are valid or are sliced in two parts, are * accepted */ for (boffset = 0; boffset < ftl->block_size; boffset += SM_SECTOR_SIZE) { /* This shouldn't happen anyway */ if (sm_read_sector(ftl, zone, block, boffset, NULL, &oob)) return -2; test_lba = sm_read_lba(&oob); if (lbas[i] != test_lba) lbas[++i] = test_lba; /* If we found three different LBAs, something is fishy */ if (i == 3) return -EIO; } /* If the block is sliced (partially erased usually) erase it */ if (i == 2) { sm_erase_block(ftl, zone, block, 1); return 1; } return 0; } /* ----------------- media scanning --------------------------------- */ static const struct chs_entry chs_table[] = { { 1, 125, 4, 4 }, { 2, 125, 4, 8 }, { 4, 250, 4, 8 }, { 8, 250, 4, 16 }, { 16, 500, 4, 16 }, { 32, 500, 8, 16 }, { 64, 500, 8, 32 }, { 128, 500, 16, 32 }, { 256, 1000, 16, 32 }, { 512, 1015, 32, 63 }, { 1024, 985, 33, 63 }, { 2048, 985, 33, 63 }, { 0 }, }; static const uint8_t cis_signature[] = { 0x01, 0x03, 0xD9, 0x01, 0xFF, 0x18, 0x02, 0xDF, 0x01, 0x20 }; /* Find out media parameters. * This ideally has to be based on nand id, but for now device size is enough */ static int sm_get_media_info(struct sm_ftl *ftl, struct mtd_info *mtd) { int i; int size_in_megs = mtd->size / (1024 * 1024); ftl->readonly = mtd->type == MTD_ROM; /* Manual settings for very old devices */ ftl->zone_count = 1; ftl->smallpagenand = 0; switch (size_in_megs) { case 1: /* 1 MiB flash/rom SmartMedia card (256 byte pages)*/ ftl->zone_size = 256; ftl->max_lba = 250; ftl->block_size = 8 * SM_SECTOR_SIZE; ftl->smallpagenand = 1; break; case 2: /* 2 MiB flash SmartMedia (256 byte pages)*/ if (mtd->writesize == SM_SMALL_PAGE) { ftl->zone_size = 512; ftl->max_lba = 500; ftl->block_size = 8 * SM_SECTOR_SIZE; ftl->smallpagenand = 1; /* 2 MiB rom SmartMedia */ } else { if (!ftl->readonly) return -ENODEV; ftl->zone_size = 256; ftl->max_lba = 250; ftl->block_size = 16 * SM_SECTOR_SIZE; } break; case 4: /* 4 MiB flash/rom SmartMedia device */ ftl->zone_size = 512; ftl->max_lba = 500; ftl->block_size = 16 * SM_SECTOR_SIZE; break; case 8: /* 8 MiB flash/rom SmartMedia device */ ftl->zone_size = 1024; ftl->max_lba = 1000; ftl->block_size = 16 * SM_SECTOR_SIZE; } /* Minimum xD size is 16MiB. Also, all xD cards have standard zone * sizes. SmartMedia cards exist up to 128 MiB and have same layout */ if (size_in_megs >= 16) { ftl->zone_count = size_in_megs / 16; ftl->zone_size = 1024; ftl->max_lba = 1000; ftl->block_size = 32 * SM_SECTOR_SIZE; } /* Test for proper write,erase and oob sizes */ if (mtd->erasesize > ftl->block_size) return -ENODEV; if (mtd->writesize > SM_SECTOR_SIZE) return -ENODEV; if (ftl->smallpagenand && mtd->oobsize < SM_SMALL_OOB_SIZE) return -ENODEV; if (!ftl->smallpagenand && mtd->oobsize < SM_OOB_SIZE) return -ENODEV; /* We use OOB */ if (!mtd_has_oob(mtd)) return -ENODEV; /* Find geometry information */ for (i = 0 ; i < ARRAY_SIZE(chs_table) ; i++) { if (chs_table[i].size == size_in_megs) { ftl->cylinders = chs_table[i].cyl; ftl->heads = chs_table[i].head; ftl->sectors = chs_table[i].sec; return 0; } } sm_printk("media has unknown size : %dMiB", size_in_megs); ftl->cylinders = 985; ftl->heads = 33; ftl->sectors = 63; return 0; } /* Validate the CIS */ static int sm_read_cis(struct sm_ftl *ftl) { struct sm_oob oob; if (sm_read_sector(ftl, 0, ftl->cis_block, ftl->cis_boffset, ftl->cis_buffer, &oob)) return -EIO; if (!sm_sector_valid(&oob) || !sm_block_valid(&oob)) return -EIO; if (!memcmp(ftl->cis_buffer + ftl->cis_page_offset, cis_signature, sizeof(cis_signature))) { return 0; } return -EIO; } /* Scan the media for the CIS */ static int sm_find_cis(struct sm_ftl *ftl) { struct sm_oob oob; int block, boffset; int block_found = 0; int cis_found = 0; /* Search for first valid block */ for (block = 0 ; block < ftl->zone_size - ftl->max_lba ; block++) { if (sm_read_sector(ftl, 0, block, 0, NULL, &oob)) continue; if (!sm_block_valid(&oob)) continue; block_found = 1; break; } if (!block_found) return -EIO; /* Search for first valid sector in this block */ for (boffset = 0 ; boffset < ftl->block_size; boffset += SM_SECTOR_SIZE) { if (sm_read_sector(ftl, 0, block, boffset, NULL, &oob)) continue; if (!sm_sector_valid(&oob)) continue; break; } if (boffset == ftl->block_size) return -EIO; ftl->cis_block = block; ftl->cis_boffset = boffset; ftl->cis_page_offset = 0; cis_found = !sm_read_cis(ftl); if (!cis_found) { ftl->cis_page_offset = SM_SMALL_PAGE; cis_found = !sm_read_cis(ftl); } if (cis_found) { dbg("CIS block found at offset %x", block * ftl->block_size + boffset + ftl->cis_page_offset); return 0; } return -EIO; } /* Basic test to determine if underlying mtd device if functional */ static int sm_recheck_media(struct sm_ftl *ftl) { if (sm_read_cis(ftl)) { if (!ftl->unstable) { sm_printk("media unstable, not allowing writes"); ftl->unstable = 1; } return -EIO; } return 0; } /* Initialize a FTL zone */ static int sm_init_zone(struct sm_ftl *ftl, int zone_num) { struct ftl_zone *zone = &ftl->zones[zone_num]; struct sm_oob oob; uint16_t block; int lba; int i = 0; int len; dbg("initializing zone %d", zone_num); /* Allocate memory for FTL table */ zone->lba_to_phys_table = kmalloc_array(ftl->max_lba, 2, GFP_KERNEL); if (!zone->lba_to_phys_table) return -ENOMEM; memset(zone->lba_to_phys_table, -1, ftl->max_lba * 2); /* Allocate memory for free sectors FIFO */ if (kfifo_alloc(&zone->free_sectors, ftl->zone_size * 2, GFP_KERNEL)) { kfree(zone->lba_to_phys_table); return -ENOMEM; } /* Now scan the zone */ for (block = 0 ; block < ftl->zone_size ; block++) { /* Skip blocks till the CIS (including) */ if (zone_num == 0 && block <= ftl->cis_block) continue; /* Read the oob of first sector */ if (sm_read_sector(ftl, zone_num, block, 0, NULL, &oob)) { kfifo_free(&zone->free_sectors); kfree(zone->lba_to_phys_table); return -EIO; } /* Test to see if block is erased. It is enough to test * first sector, because erase happens in one shot */ if (sm_block_erased(&oob)) { kfifo_in(&zone->free_sectors, (unsigned char *)&block, 2); continue; } /* If block is marked as bad, skip it */ /* This assumes we can trust first sector*/ /* However the way the block valid status is defined, ensures * very low probability of failure here */ if (!sm_block_valid(&oob)) { dbg("PH %04d <-> ", block); continue; } lba = sm_read_lba(&oob); /* Invalid LBA means that block is damaged. */ /* We can try to erase it, or mark it as bad, but * lets leave that to recovery application */ if (lba == -2 || lba >= ftl->max_lba) { dbg("PH %04d <-> LBA %04d(bad)", block, lba); continue; } /* If there is no collision, * just put the sector in the FTL table */ if (zone->lba_to_phys_table[lba] < 0) { dbg_verbose("PH %04d <-> LBA %04d", block, lba); zone->lba_to_phys_table[lba] = block; continue; } sm_printk("collision" " of LBA %d between blocks %d and %d in zone %d", lba, zone->lba_to_phys_table[lba], block, zone_num); /* Test that this block is valid*/ if (sm_check_block(ftl, zone_num, block)) continue; /* Test now the old block */ if (sm_check_block(ftl, zone_num, zone->lba_to_phys_table[lba])) { zone->lba_to_phys_table[lba] = block; continue; } /* If both blocks are valid and share same LBA, it means that * they hold different versions of same data. It not * known which is more recent, thus just erase one of them */ sm_printk("both blocks are valid, erasing the later"); sm_erase_block(ftl, zone_num, block, 1); } dbg("zone initialized"); zone->initialized = 1; /* No free sectors, means that the zone is heavily damaged, write won't * work, but it can still can be (partially) read */ if (!kfifo_len(&zone->free_sectors)) { sm_printk("no free blocks in zone %d", zone_num); return 0; } /* Randomize first block we write to */ get_random_bytes(&i, 2); i %= (kfifo_len(&zone->free_sectors) / 2); while (i--) { len = kfifo_out(&zone->free_sectors, (unsigned char *)&block, 2); WARN_ON(len != 2); kfifo_in(&zone->free_sectors, (const unsigned char *)&block, 2); } return 0; } /* Get and automatically initialize an FTL mapping for one zone */ static struct ftl_zone *sm_get_zone(struct sm_ftl *ftl, int zone_num) { struct ftl_zone *zone; int error; BUG_ON(zone_num >= ftl->zone_count); zone = &ftl->zones[zone_num]; if (!zone->initialized) { error = sm_init_zone(ftl, zone_num); if (error) return ERR_PTR(error); } return zone; } /* ----------------- cache handling ------------------------------------------*/ /* Initialize the one block cache */ static void sm_cache_init(struct sm_ftl *ftl) { ftl->cache_data_invalid_bitmap = 0xFFFFFFFF; ftl->cache_clean = 1; ftl->cache_zone = -1; ftl->cache_block = -1; /*memset(ftl->cache_data, 0xAA, ftl->block_size);*/ } /* Put sector in one block cache */ static void sm_cache_put(struct sm_ftl *ftl, char *buffer, int boffset) { memcpy(ftl->cache_data + boffset, buffer, SM_SECTOR_SIZE); clear_bit(boffset / SM_SECTOR_SIZE, &ftl->cache_data_invalid_bitmap); ftl->cache_clean = 0; } /* Read a sector from the cache */ static int sm_cache_get(struct sm_ftl *ftl, char *buffer, int boffset) { if (test_bit(boffset / SM_SECTOR_SIZE, &ftl->cache_data_invalid_bitmap)) return -1; memcpy(buffer, ftl->cache_data + boffset, SM_SECTOR_SIZE); return 0; } /* Write the cache to hardware */ static int sm_cache_flush(struct sm_ftl *ftl) { struct ftl_zone *zone; int sector_num; uint16_t write_sector; int zone_num = ftl->cache_zone; int block_num; if (ftl->cache_clean) return 0; if (ftl->unstable) return -EIO; BUG_ON(zone_num < 0); zone = &ftl->zones[zone_num]; block_num = zone->lba_to_phys_table[ftl->cache_block]; /* Try to read all unread areas of the cache block*/ for_each_set_bit(sector_num, &ftl->cache_data_invalid_bitmap, ftl->block_size / SM_SECTOR_SIZE) { if (!sm_read_sector(ftl, zone_num, block_num, sector_num * SM_SECTOR_SIZE, ftl->cache_data + sector_num * SM_SECTOR_SIZE, NULL)) clear_bit(sector_num, &ftl->cache_data_invalid_bitmap); } restart: if (ftl->unstable) return -EIO; /* If there are no spare blocks, */ /* we could still continue by erasing/writing the current block, * but for such worn out media it doesn't worth the trouble, * and the dangers */ if (kfifo_out(&zone->free_sectors, (unsigned char *)&write_sector, 2) != 2) { dbg("no free sectors for write!"); return -EIO; } if (sm_write_block(ftl, ftl->cache_data, zone_num, write_sector, ftl->cache_block, ftl->cache_data_invalid_bitmap)) goto restart; /* Update the FTL table */ zone->lba_to_phys_table[ftl->cache_block] = write_sector; /* Write succesfull, so erase and free the old block */ if (block_num > 0) sm_erase_block(ftl, zone_num, block_num, 1); sm_cache_init(ftl); return 0; } /* flush timer, runs a second after last write */ static void sm_cache_flush_timer(struct timer_list *t) { struct sm_ftl *ftl = from_timer(ftl, t, timer); queue_work(cache_flush_workqueue, &ftl->flush_work); } /* cache flush work, kicked by timer */ static void sm_cache_flush_work(struct work_struct *work) { struct sm_ftl *ftl = container_of(work, struct sm_ftl, flush_work); mutex_lock(&ftl->mutex); sm_cache_flush(ftl); mutex_unlock(&ftl->mutex); return; } /* ---------------- outside interface -------------------------------------- */ /* outside interface: read a sector */ static int sm_read(struct mtd_blktrans_dev *dev, unsigned long sect_no, char *buf) { struct sm_ftl *ftl = dev->priv; struct ftl_zone *zone; int error = 0, in_cache = 0; int zone_num, block, boffset; sm_break_offset(ftl, sect_no << 9, &zone_num, &block, &boffset); mutex_lock(&ftl->mutex); zone = sm_get_zone(ftl, zone_num); if (IS_ERR(zone)) { error = PTR_ERR(zone); goto unlock; } /* Have to look at cache first */ if (ftl->cache_zone == zone_num && ftl->cache_block == block) { in_cache = 1; if (!sm_cache_get(ftl, buf, boffset)) goto unlock; } /* Translate the block and return if doesn't exist in the table */ block = zone->lba_to_phys_table[block]; if (block == -1) { memset(buf, 0xFF, SM_SECTOR_SIZE); goto unlock; } if (sm_read_sector(ftl, zone_num, block, boffset, buf, NULL)) { error = -EIO; goto unlock; } if (in_cache) sm_cache_put(ftl, buf, boffset); unlock: mutex_unlock(&ftl->mutex); return error; } /* outside interface: write a sector */ static int sm_write(struct mtd_blktrans_dev *dev, unsigned long sec_no, char *buf) { struct sm_ftl *ftl = dev->priv; struct ftl_zone *zone; int error = 0, zone_num, block, boffset; BUG_ON(ftl->readonly); sm_break_offset(ftl, sec_no << 9, &zone_num, &block, &boffset); /* No need in flush thread running now */ del_timer(&ftl->timer); mutex_lock(&ftl->mutex); zone = sm_get_zone(ftl, zone_num); if (IS_ERR(zone)) { error = PTR_ERR(zone); goto unlock; } /* If entry is not in cache, flush it */ if (ftl->cache_block != block || ftl->cache_zone != zone_num) { error = sm_cache_flush(ftl); if (error) goto unlock; ftl->cache_block = block; ftl->cache_zone = zone_num; } sm_cache_put(ftl, buf, boffset); unlock: mod_timer(&ftl->timer, jiffies + msecs_to_jiffies(cache_timeout)); mutex_unlock(&ftl->mutex); return error; } /* outside interface: flush everything */ static int sm_flush(struct mtd_blktrans_dev *dev) { struct sm_ftl *ftl = dev->priv; int retval; mutex_lock(&ftl->mutex); retval = sm_cache_flush(ftl); mutex_unlock(&ftl->mutex); return retval; } /* outside interface: device is released */ static void sm_release(struct mtd_blktrans_dev *dev) { struct sm_ftl *ftl = dev->priv; del_timer_sync(&ftl->timer); cancel_work_sync(&ftl->flush_work); mutex_lock(&ftl->mutex); sm_cache_flush(ftl); mutex_unlock(&ftl->mutex); } /* outside interface: get geometry */ static int sm_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo) { struct sm_ftl *ftl = dev->priv; geo->heads = ftl->heads; geo->sectors = ftl->sectors; geo->cylinders = ftl->cylinders; return 0; } /* external interface: main initialization function */ static void sm_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd) { struct mtd_blktrans_dev *trans; struct sm_ftl *ftl; /* Allocate & initialize our private structure */ ftl = kzalloc(sizeof(struct sm_ftl), GFP_KERNEL); if (!ftl) goto error1; mutex_init(&ftl->mutex); timer_setup(&ftl->timer, sm_cache_flush_timer, 0); INIT_WORK(&ftl->flush_work, sm_cache_flush_work); /* Read media information */ if (sm_get_media_info(ftl, mtd)) { dbg("found unsupported mtd device, aborting"); goto error2; } /* Allocate temporary CIS buffer for read retry support */ ftl->cis_buffer = kzalloc(SM_SECTOR_SIZE, GFP_KERNEL); if (!ftl->cis_buffer) goto error2; /* Allocate zone array, it will be initialized on demand */ ftl->zones = kcalloc(ftl->zone_count, sizeof(struct ftl_zone), GFP_KERNEL); if (!ftl->zones) goto error3; /* Allocate the cache*/ ftl->cache_data = kzalloc(ftl->block_size, GFP_KERNEL); if (!ftl->cache_data) goto error4; sm_cache_init(ftl); /* Allocate upper layer structure and initialize it */ trans = kzalloc(sizeof(struct mtd_blktrans_dev), GFP_KERNEL); if (!trans) goto error5; ftl->trans = trans; trans->priv = ftl; trans->tr = tr; trans->mtd = mtd; trans->devnum = -1; trans->size = (ftl->block_size * ftl->max_lba * ftl->zone_count) >> 9; trans->readonly = ftl->readonly; if (sm_find_cis(ftl)) { dbg("CIS not found on mtd device, aborting"); goto error6; } ftl->disk_attributes = sm_create_sysfs_attributes(ftl); if (!ftl->disk_attributes) goto error6; trans->disk_attributes = ftl->disk_attributes; sm_printk("Found %d MiB xD/SmartMedia FTL on mtd%d", (int)(mtd->size / (1024 * 1024)), mtd->index); dbg("FTL layout:"); dbg("%d zone(s), each consists of %d blocks (+%d spares)", ftl->zone_count, ftl->max_lba, ftl->zone_size - ftl->max_lba); dbg("each block consists of %d bytes", ftl->block_size); /* Register device*/ if (add_mtd_blktrans_dev(trans)) { dbg("error in mtdblktrans layer"); goto error6; } return; error6: kfree(trans); error5: kfree(ftl->cache_data); error4: kfree(ftl->zones); error3: kfree(ftl->cis_buffer); error2: kfree(ftl); error1: return; } /* main interface: device {surprise,} removal */ static void sm_remove_dev(struct mtd_blktrans_dev *dev) { struct sm_ftl *ftl = dev->priv; int i; del_mtd_blktrans_dev(dev); ftl->trans = NULL; for (i = 0 ; i < ftl->zone_count; i++) { if (!ftl->zones[i].initialized) continue; kfree(ftl->zones[i].lba_to_phys_table); kfifo_free(&ftl->zones[i].free_sectors); } sm_delete_sysfs_attributes(ftl); kfree(ftl->cis_buffer); kfree(ftl->zones); kfree(ftl->cache_data); kfree(ftl); } static struct mtd_blktrans_ops sm_ftl_ops = { .name = "smblk", .major = 0, .part_bits = SM_FTL_PARTN_BITS, .blksize = SM_SECTOR_SIZE, .getgeo = sm_getgeo, .add_mtd = sm_add_mtd, .remove_dev = sm_remove_dev, .readsect = sm_read, .writesect = sm_write, .flush = sm_flush, .release = sm_release, .owner = THIS_MODULE, }; static __init int sm_module_init(void) { int error = 0; cache_flush_workqueue = create_freezable_workqueue("smflush"); if (!cache_flush_workqueue) return -ENOMEM; error = register_mtd_blktrans(&sm_ftl_ops); if (error) destroy_workqueue(cache_flush_workqueue); return error; } static void __exit sm_module_exit(void) { destroy_workqueue(cache_flush_workqueue); deregister_mtd_blktrans(&sm_ftl_ops); } module_init(sm_module_init); module_exit(sm_module_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Maxim Levitsky "); MODULE_DESCRIPTION("Smartmedia/xD mtd translation layer");