diff options
Diffstat (limited to 'drivers/mtd/ftl.c')
| -rw-r--r-- | drivers/mtd/ftl.c | 1115 |
1 files changed, 1115 insertions, 0 deletions
diff --git a/drivers/mtd/ftl.c b/drivers/mtd/ftl.c new file mode 100644 index 0000000..18cc884 --- /dev/null +++ b/drivers/mtd/ftl.c @@ -0,0 +1,1115 @@ +/* This version ported to the Linux-MTD system by dwmw2@infradead.org + * $Id: ftl.c,v 1.54 2004/11/16 18:33:15 dwmw2 Exp $ + * + * Fixes: Arnaldo Carvalho de Melo <acme@conectiva.com.br> + * - fixes some leaks on failure in build_maps and ftl_notify_add, cleanups + * + * Based on: + */ +/*====================================================================== + + A Flash Translation Layer memory card driver + + This driver implements a disk-like block device driver with an + apparent block size of 512 bytes for flash memory cards. + + ftl_cs.c 1.62 2000/02/01 00:59:04 + + The contents of this file are subject to the Mozilla Public + License Version 1.1 (the "License"); you may not use this file + except in compliance with the License. You may obtain a copy of + the License at http://www.mozilla.org/MPL/ + + Software distributed under the License is distributed on an "AS + IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or + implied. See the License for the specific language governing + rights and limitations under the License. + + The initial developer of the original code is David A. Hinds + <dahinds@users.sourceforge.net>. Portions created by David A. Hinds + are Copyright (C) 1999 David A. Hinds. All Rights Reserved. + + Alternatively, the contents of this file may be used under the + terms of the GNU General Public License version 2 (the "GPL"), in + which case the provisions of the GPL are applicable instead of the + above. If you wish to allow the use of your version of this file + only under the terms of the GPL and not to allow others to use + your version of this file under the MPL, indicate your decision + by deleting the provisions above and replace them with the notice + and other provisions required by the GPL. If you do not delete + the provisions above, a recipient may use your version of this + file under either the MPL or the GPL. + + LEGAL NOTE: The FTL format is patented by M-Systems. They have + granted a license for its use with PCMCIA devices: + + "M-Systems grants a royalty-free, non-exclusive license under + any presently existing M-Systems intellectual property rights + necessary for the design and development of FTL-compatible + drivers, file systems and utilities using the data formats with + PCMCIA PC Cards as described in the PCMCIA Flash Translation + Layer (FTL) Specification." + + Use of the FTL format for non-PCMCIA applications may be an + infringement of these patents. For additional information, + contact M-Systems (http://www.m-sys.com) directly. + +======================================================================*/ +#include <linux/mtd/blktrans.h> +#include <linux/module.h> +#include <linux/mtd/mtd.h> +/*#define PSYCHO_DEBUG */ + +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/ptrace.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/timer.h> +#include <linux/major.h> +#include <linux/fs.h> +#include <linux/init.h> +#include <linux/hdreg.h> +#include <linux/vmalloc.h> +#include <linux/blkpg.h> +#include <asm/uaccess.h> + +#include <linux/mtd/ftl.h> + +/*====================================================================*/ + +/* Parameters that can be set with 'insmod' */ +static int shuffle_freq = 50; +module_param(shuffle_freq, int, 0); + +/*====================================================================*/ + +/* Major device # for FTL device */ +#ifndef FTL_MAJOR +#define FTL_MAJOR 44 +#endif + + +/*====================================================================*/ + +/* Maximum number of separate memory devices we'll allow */ +#define MAX_DEV 4 + +/* Maximum number of regions per device */ +#define MAX_REGION 4 + +/* Maximum number of partitions in an FTL region */ +#define PART_BITS 4 + +/* Maximum number of outstanding erase requests per socket */ +#define MAX_ERASE 8 + +/* Sector size -- shouldn't need to change */ +#define SECTOR_SIZE 512 + + +/* Each memory region corresponds to a minor device */ +typedef struct partition_t { + struct mtd_blktrans_dev mbd; + u_int32_t state; + u_int32_t *VirtualBlockMap; + u_int32_t *VirtualPageMap; + u_int32_t FreeTotal; + struct eun_info_t { + u_int32_t Offset; + u_int32_t EraseCount; + u_int32_t Free; + u_int32_t Deleted; + } *EUNInfo; + struct xfer_info_t { + u_int32_t Offset; + u_int32_t EraseCount; + u_int16_t state; + } *XferInfo; + u_int16_t bam_index; + u_int32_t *bam_cache; + u_int16_t DataUnits; + u_int32_t BlocksPerUnit; + erase_unit_header_t header; +#if 0 + region_info_t region; + memory_handle_t handle; +#endif +} partition_t; + +void ftl_freepart(partition_t *part); + +/* Partition state flags */ +#define FTL_FORMATTED 0x01 + +/* Transfer unit states */ +#define XFER_UNKNOWN 0x00 +#define XFER_ERASING 0x01 +#define XFER_ERASED 0x02 +#define XFER_PREPARED 0x03 +#define XFER_FAILED 0x04 + +/*====================================================================*/ + + +static void ftl_erase_callback(struct erase_info *done); + + +/*====================================================================== + + Scan_header() checks to see if a memory region contains an FTL + partition. build_maps() reads all the erase unit headers, builds + the erase unit map, and then builds the virtual page map. + +======================================================================*/ + +static int scan_header(partition_t *part) +{ + erase_unit_header_t header; + loff_t offset, max_offset; + size_t ret; + int err; + part->header.FormattedSize = 0; + max_offset = (0x100000<part->mbd.mtd->size)?0x100000:part->mbd.mtd->size; + /* Search first megabyte for a valid FTL header */ + for (offset = 0; + (offset + sizeof(header)) < max_offset; + offset += part->mbd.mtd->erasesize ? : 0x2000) { + + err = part->mbd.mtd->read(part->mbd.mtd, offset, sizeof(header), &ret, + (unsigned char *)&header); + + if (err) + return err; + + if (strcmp(header.DataOrgTuple+3, "FTL100") == 0) break; + } + + if (offset == max_offset) { + printk(KERN_NOTICE "ftl_cs: FTL header not found.\n"); + return -ENOENT; + } + if (header.BlockSize != 9 || + (header.EraseUnitSize < 10) || (header.EraseUnitSize > 31) || + (header.NumTransferUnits >= le16_to_cpu(header.NumEraseUnits))) { + printk(KERN_NOTICE "ftl_cs: FTL header corrupt!\n"); + return -1; + } + if ((1 << header.EraseUnitSize) != part->mbd.mtd->erasesize) { + printk(KERN_NOTICE "ftl: FTL EraseUnitSize %x != MTD erasesize %x\n", + 1 << header.EraseUnitSize,part->mbd.mtd->erasesize); + return -1; + } + part->header = header; + return 0; +} + +static int build_maps(partition_t *part) +{ + erase_unit_header_t header; + u_int16_t xvalid, xtrans, i; + u_int blocks, j; + int hdr_ok, ret = -1; + ssize_t retval; + loff_t offset; + + /* Set up erase unit maps */ + part->DataUnits = le16_to_cpu(part->header.NumEraseUnits) - + part->header.NumTransferUnits; + part->EUNInfo = kmalloc(part->DataUnits * sizeof(struct eun_info_t), + GFP_KERNEL); + if (!part->EUNInfo) + goto out; + for (i = 0; i < part->DataUnits; i++) + part->EUNInfo[i].Offset = 0xffffffff; + part->XferInfo = + kmalloc(part->header.NumTransferUnits * sizeof(struct xfer_info_t), + GFP_KERNEL); + if (!part->XferInfo) + goto out_EUNInfo; + + xvalid = xtrans = 0; + for (i = 0; i < le16_to_cpu(part->header.NumEraseUnits); i++) { + offset = ((i + le16_to_cpu(part->header.FirstPhysicalEUN)) + << part->header.EraseUnitSize); + ret = part->mbd.mtd->read(part->mbd.mtd, offset, sizeof(header), &retval, + (unsigned char *)&header); + + if (ret) + goto out_XferInfo; + + ret = -1; + /* Is this a transfer partition? */ + hdr_ok = (strcmp(header.DataOrgTuple+3, "FTL100") == 0); + if (hdr_ok && (le16_to_cpu(header.LogicalEUN) < part->DataUnits) && + (part->EUNInfo[le16_to_cpu(header.LogicalEUN)].Offset == 0xffffffff)) { + part->EUNInfo[le16_to_cpu(header.LogicalEUN)].Offset = offset; + part->EUNInfo[le16_to_cpu(header.LogicalEUN)].EraseCount = + le32_to_cpu(header.EraseCount); + xvalid++; + } else { + if (xtrans == part->header.NumTransferUnits) { + printk(KERN_NOTICE "ftl_cs: format error: too many " + "transfer units!\n"); + goto out_XferInfo; + } + if (hdr_ok && (le16_to_cpu(header.LogicalEUN) == 0xffff)) { + part->XferInfo[xtrans].state = XFER_PREPARED; + part->XferInfo[xtrans].EraseCount = le32_to_cpu(header.EraseCount); + } else { + part->XferInfo[xtrans].state = XFER_UNKNOWN; + /* Pick anything reasonable for the erase count */ + part->XferInfo[xtrans].EraseCount = + le32_to_cpu(part->header.EraseCount); + } + part->XferInfo[xtrans].Offset = offset; + xtrans++; + } + } + /* Check for format trouble */ + header = part->header; + if ((xtrans != header.NumTransferUnits) || + (xvalid+xtrans != le16_to_cpu(header.NumEraseUnits))) { + printk(KERN_NOTICE "ftl_cs: format error: erase units " + "don't add up!\n"); + goto out_XferInfo; + } + + /* Set up virtual page map */ + blocks = le32_to_cpu(header.FormattedSize) >> header.BlockSize; + part->VirtualBlockMap = vmalloc(blocks * sizeof(u_int32_t)); + if (!part->VirtualBlockMap) + goto out_XferInfo; + + memset(part->VirtualBlockMap, 0xff, blocks * sizeof(u_int32_t)); + part->BlocksPerUnit = (1 << header.EraseUnitSize) >> header.BlockSize; + + part->bam_cache = kmalloc(part->BlocksPerUnit * sizeof(u_int32_t), + GFP_KERNEL); + if (!part->bam_cache) + goto out_VirtualBlockMap; + + part->bam_index = 0xffff; + part->FreeTotal = 0; + + for (i = 0; i < part->DataUnits; i++) { + part->EUNInfo[i].Free = 0; + part->EUNInfo[i].Deleted = 0; + offset = part->EUNInfo[i].Offset + le32_to_cpu(header.BAMOffset); + + ret = part->mbd.mtd->read(part->mbd.mtd, offset, + part->BlocksPerUnit * sizeof(u_int32_t), &retval, + (unsigned char *)part->bam_cache); + + if (ret) + goto out_bam_cache; + + for (j = 0; j < part->BlocksPerUnit; j++) { + if (BLOCK_FREE(le32_to_cpu(part->bam_cache[j]))) { + part->EUNInfo[i].Free++; + part->FreeTotal++; + } else if ((BLOCK_TYPE(le32_to_cpu(part->bam_cache[j])) == BLOCK_DATA) && + (BLOCK_NUMBER(le32_to_cpu(part->bam_cache[j])) < blocks)) + part->VirtualBlockMap[BLOCK_NUMBER(le32_to_cpu(part->bam_cache[j]))] = + (i << header.EraseUnitSize) + (j << header.BlockSize); + else if (BLOCK_DELETED(le32_to_cpu(part->bam_cache[j]))) + part->EUNInfo[i].Deleted++; + } + } + + ret = 0; + goto out; + +out_bam_cache: + kfree(part->bam_cache); +out_VirtualBlockMap: + vfree(part->VirtualBlockMap); +out_XferInfo: + kfree(part->XferInfo); +out_EUNInfo: + kfree(part->EUNInfo); +out: + return ret; +} /* build_maps */ + +/*====================================================================== + + Erase_xfer() schedules an asynchronous erase operation for a + transfer unit. + +======================================================================*/ + +static int erase_xfer(partition_t *part, + u_int16_t xfernum) +{ + int ret; + struct xfer_info_t *xfer; + struct erase_info *erase; + + xfer = &part->XferInfo[xfernum]; + DEBUG(1, "ftl_cs: erasing xfer unit at 0x%x\n", xfer->Offset); + xfer->state = XFER_ERASING; + + /* Is there a free erase slot? Always in MTD. */ + + + erase=kmalloc(sizeof(struct erase_info), GFP_KERNEL); + if (!erase) + return -ENOMEM; + + erase->callback = ftl_erase_callback; + erase->addr = xfer->Offset; + erase->len = 1 << part->header.EraseUnitSize; + erase->priv = (u_long)part; + + ret = part->mbd.mtd->erase(part->mbd.mtd, erase); + + if (!ret) + xfer->EraseCount++; + else + kfree(erase); + + return ret; +} /* erase_xfer */ + +/*====================================================================== + + Prepare_xfer() takes a freshly erased transfer unit and gives + it an appropriate header. + +======================================================================*/ + +static void ftl_erase_callback(struct erase_info *erase) +{ + partition_t *part; + struct xfer_info_t *xfer; + int i; + + /* Look up the transfer unit */ + part = (partition_t *)(erase->priv); + + for (i = 0; i < part->header.NumTransferUnits; i++) + if (part->XferInfo[i].Offset == erase->addr) break; + + if (i == part->header.NumTransferUnits) { + printk(KERN_NOTICE "ftl_cs: internal error: " + "erase lookup failed!\n"); + return; + } + + xfer = &part->XferInfo[i]; + if (erase->state == MTD_ERASE_DONE) + xfer->state = XFER_ERASED; + else { + xfer->state = XFER_FAILED; + printk(KERN_NOTICE "ftl_cs: erase failed: state = %d\n", + erase->state); + } + + kfree(erase); + +} /* ftl_erase_callback */ + +static int prepare_xfer(partition_t *part, int i) +{ + erase_unit_header_t header; + struct xfer_info_t *xfer; + int nbam, ret; + u_int32_t ctl; + ssize_t retlen; + loff_t offset; + + xfer = &part->XferInfo[i]; + xfer->state = XFER_FAILED; + + DEBUG(1, "ftl_cs: preparing xfer unit at 0x%x\n", xfer->Offset); + + /* Write the transfer unit header */ + header = part->header; + header.LogicalEUN = cpu_to_le16(0xffff); + header.EraseCount = cpu_to_le32(xfer->EraseCount); + + ret = part->mbd.mtd->write(part->mbd.mtd, xfer->Offset, sizeof(header), + &retlen, (u_char *)&header); + + if (ret) { + return ret; + } + + /* Write the BAM stub */ + nbam = (part->BlocksPerUnit * sizeof(u_int32_t) + + le32_to_cpu(part->header.BAMOffset) + SECTOR_SIZE - 1) / SECTOR_SIZE; + + offset = xfer->Offset + le32_to_cpu(part->header.BAMOffset); + ctl = cpu_to_le32(BLOCK_CONTROL); + + for (i = 0; i < nbam; i++, offset += sizeof(u_int32_t)) { + + ret = part->mbd.mtd->write(part->mbd.mtd, offset, sizeof(u_int32_t), + &retlen, (u_char *)&ctl); + + if (ret) + return ret; + } + xfer->state = XFER_PREPARED; + return 0; + +} /* prepare_xfer */ + +/*====================================================================== + + Copy_erase_unit() takes a full erase block and a transfer unit, + copies everything to the transfer unit, then swaps the block + pointers. + + All data blocks are copied to the corresponding blocks in the + target unit, so the virtual block map does not need to be + updated. + +======================================================================*/ + +static int copy_erase_unit(partition_t *part, u_int16_t srcunit, + u_int16_t xferunit) +{ + u_char buf[SECTOR_SIZE]; + struct eun_info_t *eun; + struct xfer_info_t *xfer; + u_int32_t src, dest, free, i; + u_int16_t unit; + int ret; + ssize_t retlen; + loff_t offset; + u_int16_t srcunitswap = cpu_to_le16(srcunit); + + eun = &part->EUNInfo[srcunit]; + xfer = &part->XferInfo[xferunit]; + DEBUG(2, "ftl_cs: copying block 0x%x to 0x%x\n", + eun->Offset, xfer->Offset); + + + /* Read current BAM */ + if (part->bam_index != srcunit) { + + offset = eun->Offset + le32_to_cpu(part->header.BAMOffset); + + ret = part->mbd.mtd->read(part->mbd.mtd, offset, + part->BlocksPerUnit * sizeof(u_int32_t), + &retlen, (u_char *) (part->bam_cache)); + + /* mark the cache bad, in case we get an error later */ + part->bam_index = 0xffff; + + if (ret) { + printk( KERN_WARNING "ftl: Failed to read BAM cache in copy_erase_unit()!\n"); + return ret; + } + } + + /* Write the LogicalEUN for the transfer unit */ + xfer->state = XFER_UNKNOWN; + offset = xfer->Offset + 20; /* Bad! */ + unit = cpu_to_le16(0x7fff); + + ret = part->mbd.mtd->write(part->mbd.mtd, offset, sizeof(u_int16_t), + &retlen, (u_char *) &unit); + + if (ret) { + printk( KERN_WARNING "ftl: Failed to write back to BAM cache in copy_erase_unit()!\n"); + return ret; + } + + /* Copy all data blocks from source unit to transfer unit */ + src = eun->Offset; dest = xfer->Offset; + + free = 0; + ret = 0; + for (i = 0; i < part->BlocksPerUnit; i++) { + switch (BLOCK_TYPE(le32_to_cpu(part->bam_cache[i]))) { + case BLOCK_CONTROL: + /* This gets updated later */ + break; + case BLOCK_DATA: + case BLOCK_REPLACEMENT: + ret = part->mbd.mtd->read(part->mbd.mtd, src, SECTOR_SIZE, + &retlen, (u_char *) buf); + if (ret) { + printk(KERN_WARNING "ftl: Error reading old xfer unit in copy_erase_unit\n"); + return ret; + } + + + ret = part->mbd.mtd->write(part->mbd.mtd, dest, SECTOR_SIZE, + &retlen, (u_char *) buf); + if (ret) { + printk(KERN_WARNING "ftl: Error writing new xfer unit in copy_erase_unit\n"); + return ret; + } + + break; + default: + /* All other blocks must be free */ + part->bam_cache[i] = cpu_to_le32(0xffffffff); + free++; + break; + } + src += SECTOR_SIZE; + dest += SECTOR_SIZE; + } + + /* Write the BAM to the transfer unit */ + ret = part->mbd.mtd->write(part->mbd.mtd, xfer->Offset + le32_to_cpu(part->header.BAMOffset), + part->BlocksPerUnit * sizeof(int32_t), &retlen, + (u_char *)part->bam_cache); + if (ret) { + printk( KERN_WARNING "ftl: Error writing BAM in copy_erase_unit\n"); + return ret; + } + + + /* All clear? Then update the LogicalEUN again */ + ret = part->mbd.mtd->write(part->mbd.mtd, xfer->Offset + 20, sizeof(u_int16_t), + &retlen, (u_char *)&srcunitswap); + + if (ret) { + printk(KERN_WARNING "ftl: Error writing new LogicalEUN in copy_erase_unit\n"); + return ret; + } + + + /* Update the maps and usage stats*/ + i = xfer->EraseCount; + xfer->EraseCount = eun->EraseCount; + eun->EraseCount = i; + i = xfer->Offset; + xfer->Offset = eun->Offset; + eun->Offset = i; + part->FreeTotal -= eun->Free; + part->FreeTotal += free; + eun->Free = free; + eun->Deleted = 0; + + /* Now, the cache should be valid for the new block */ + part->bam_index = srcunit; + + return 0; +} /* copy_erase_unit */ + +/*====================================================================== + + reclaim_block() picks a full erase unit and a transfer unit and + then calls copy_erase_unit() to copy one to the other. Then, it + schedules an erase on the expired block. + + What's a good way to decide which transfer unit and which erase + unit to use? Beats me. My way is to always pick the transfer + unit with the fewest erases, and usually pick the data unit with + the most deleted blocks. But with a small probability, pick the + oldest data unit instead. This means that we generally postpone + the next reclaimation as long as possible, but shuffle static + stuff around a bit for wear leveling. + +======================================================================*/ + +static int reclaim_block(partition_t *part) +{ + u_int16_t i, eun, xfer; + u_int32_t best; + int queued, ret; + + DEBUG(0, "ftl_cs: reclaiming space...\n"); + DEBUG(3, "NumTransferUnits == %x\n", part->header.NumTransferUnits); + /* Pick the least erased transfer unit */ + best = 0xffffffff; xfer = 0xffff; + do { + queued = 0; + for (i = 0; i < part->header.NumTransferUnits; i++) { + int n=0; + if (part->XferInfo[i].state == XFER_UNKNOWN) { + DEBUG(3,"XferInfo[%d].state == XFER_UNKNOWN\n",i); + n=1; + erase_xfer(part, i); + } + if (part->XferInfo[i].state == XFER_ERASING) { + DEBUG(3,"XferInfo[%d].state == XFER_ERASING\n",i); + n=1; + queued = 1; + } + else if (part->XferInfo[i].state == XFER_ERASED) { + DEBUG(3,"XferInfo[%d].state == XFER_ERASED\n",i); + n=1; + prepare_xfer(part, i); + } + if (part->XferInfo[i].state == XFER_PREPARED) { + DEBUG(3,"XferInfo[%d].state == XFER_PREPARED\n",i); + n=1; + if (part->XferInfo[i].EraseCount <= best) { + best = part->XferInfo[i].EraseCount; + xfer = i; + } + } + if (!n) + DEBUG(3,"XferInfo[%d].state == %x\n",i, part->XferInfo[i].state); + + } + if (xfer == 0xffff) { + if (queued) { + DEBUG(1, "ftl_cs: waiting for transfer " + "unit to be prepared...\n"); + if (part->mbd.mtd->sync) + part->mbd.mtd->sync(part->mbd.mtd); + } else { + static int ne = 0; + if (++ne < 5) + printk(KERN_NOTICE "ftl_cs: reclaim failed: no " + "suitable transfer units!\n"); + else + DEBUG(1, "ftl_cs: reclaim failed: no " + "suitable transfer units!\n"); + + return -EIO; + } + } + } while (xfer == 0xffff); + + eun = 0; + if ((jiffies % shuffle_freq) == 0) { + DEBUG(1, "ftl_cs: recycling freshest block...\n"); + best = 0xffffffff; + for (i = 0; i < part->DataUnits; i++) + if (part->EUNInfo[i].EraseCount <= best) { + best = part->EUNInfo[i].EraseCount; + eun = i; + } + } else { + best = 0; + for (i = 0; i < part->DataUnits; i++) + if (part->EUNInfo[i].Deleted >= best) { + best = part->EUNInfo[i].Deleted; + eun = i; + } + if (best == 0) { + static int ne = 0; + if (++ne < 5) + printk(KERN_NOTICE "ftl_cs: reclaim failed: " + "no free blocks!\n"); + else + DEBUG(1,"ftl_cs: reclaim failed: " + "no free blocks!\n"); + + return -EIO; + } + } + ret = copy_erase_unit(part, eun, xfer); + if (!ret) + erase_xfer(part, xfer); + else + printk(KERN_NOTICE "ftl_cs: copy_erase_unit failed!\n"); + return ret; +} /* reclaim_block */ + +/*====================================================================== + + Find_free() searches for a free block. If necessary, it updates + the BAM cache for the erase unit containing the free block. It + returns the block index -- the erase unit is just the currently + cached unit. If there are no free blocks, it returns 0 -- this + is never a valid data block because it contains the header. + +======================================================================*/ + +#ifdef PSYCHO_DEBUG +static void dump_lists(partition_t *part) +{ + int i; + printk(KERN_DEBUG "ftl_cs: Free total = %d\n", part->FreeTotal); + for (i = 0; i < part->DataUnits; i++) + printk(KERN_DEBUG "ftl_cs: unit %d: %d phys, %d free, " + "%d deleted\n", i, + part->EUNInfo[i].Offset >> part->header.EraseUnitSize, + part->EUNInfo[i].Free, part->EUNInfo[i].Deleted); +} +#endif + +static u_int32_t find_free(partition_t *part) +{ + u_int16_t stop, eun; + u_int32_t blk; + size_t retlen; + int ret; + + /* Find an erase unit with some free space */ + stop = (part->bam_index == 0xffff) ? 0 : part->bam_index; + eun = stop; + do { + if (part->EUNInfo[eun].Free != 0) break; + /* Wrap around at end of table */ + if (++eun == part->DataUnits) eun = 0; + } while (eun != stop); + + if (part->EUNInfo[eun].Free == 0) + return 0; + + /* Is this unit's BAM cached? */ + if (eun != part->bam_index) { + /* Invalidate cache */ + part->bam_index = 0xffff; + + ret = part->mbd.mtd->read(part->mbd.mtd, + part->EUNInfo[eun].Offset + le32_to_cpu(part->header.BAMOffset), + part->BlocksPerUnit * sizeof(u_int32_t), + &retlen, (u_char *) (part->bam_cache)); + + if (ret) { + printk(KERN_WARNING"ftl: Error reading BAM in find_free\n"); + return 0; + } + part->bam_index = eun; + } + + /* Find a free block */ + for (blk = 0; blk < part->BlocksPerUnit; blk++) + if (BLOCK_FREE(le32_to_cpu(part->bam_cache[blk]))) break; + if (blk == part->BlocksPerUnit) { +#ifdef PSYCHO_DEBUG + static int ne = 0; + if (++ne == 1) + dump_lists(part); +#endif + printk(KERN_NOTICE "ftl_cs: bad free list!\n"); + return 0; + } + DEBUG(2, "ftl_cs: found free block at %d in %d\n", blk, eun); + return blk; + +} /* find_free */ + + +/*====================================================================== + + Read a series of sectors from an FTL partition. + +======================================================================*/ + +static int ftl_read(partition_t *part, caddr_t buffer, + u_long sector, u_long nblocks) +{ + u_int32_t log_addr, bsize; + u_long i; + int ret; + size_t offset, retlen; + + DEBUG(2, "ftl_cs: ftl_read(0x%p, 0x%lx, %ld)\n", + part, sector, nblocks); + if (!(part->state & FTL_FORMATTED)) { + printk(KERN_NOTICE "ftl_cs: bad partition\n"); + return -EIO; + } + bsize = 1 << part->header.EraseUnitSize; + + for (i = 0; i < nblocks; i++) { + if (((sector+i) * SECTOR_SIZE) >= le32_to_cpu(part->header.FormattedSize)) { + printk(KERN_NOTICE "ftl_cs: bad read offset\n"); + return -EIO; + } + log_addr = part->VirtualBlockMap[sector+i]; + if (log_addr == 0xffffffff) + memset(buffer, 0, SECTOR_SIZE); + else { + offset = (part->EUNInfo[log_addr / bsize].Offset + + (log_addr % bsize)); + ret = part->mbd.mtd->read(part->mbd.mtd, offset, SECTOR_SIZE, + &retlen, (u_char *) buffer); + + if (ret) { + printk(KERN_WARNING "Error reading MTD device in ftl_read()\n"); + return ret; + } + } + buffer += SECTOR_SIZE; + } + return 0; +} /* ftl_read */ + +/*====================================================================== + + Write a series of sectors to an FTL partition + +======================================================================*/ + +static int set_bam_entry(partition_t *part, u_int32_t log_addr, + u_int32_t virt_addr) +{ + u_int32_t bsize, blk, le_virt_addr; +#ifdef PSYCHO_DEBUG + u_int32_t old_addr; +#endif + u_int16_t eun; + int ret; + size_t retlen, offset; + + DEBUG(2, "ftl_cs: set_bam_entry(0x%p, 0x%x, 0x%x)\n", + part, log_addr, virt_addr); + bsize = 1 << part->header.EraseUnitSize; + eun = log_addr / bsize; + blk = (log_addr % bsize) / SECTOR_SIZE; + offset = (part->EUNInfo[eun].Offset + blk * sizeof(u_int32_t) + + le32_to_cpu(part->header.BAMOffset)); + +#ifdef PSYCHO_DEBUG + ret = part->mbd.mtd->read(part->mbd.mtd, offset, sizeof(u_int32_t), + &retlen, (u_char *)&old_addr); + if (ret) { + printk(KERN_WARNING"ftl: Error reading old_addr in set_bam_entry: %d\n",ret); + return ret; + } + old_addr = le32_to_cpu(old_addr); + + if (((virt_addr == 0xfffffffe) && !BLOCK_FREE(old_addr)) || + ((virt_addr == 0) && (BLOCK_TYPE(old_addr) != BLOCK_DATA)) || + (!BLOCK_DELETED(virt_addr) && (old_addr != 0xfffffffe))) { + static int ne = 0; + if (++ne < 5) { + printk(KERN_NOTICE "ftl_cs: set_bam_entry() inconsistency!\n"); + printk(KERN_NOTICE "ftl_cs: log_addr = 0x%x, old = 0x%x" + ", new = 0x%x\n", log_addr, old_addr, virt_addr); + } + return -EIO; + } +#endif + le_virt_addr = cpu_to_le32(virt_addr); + if (part->bam_index == eun) { +#ifdef PSYCHO_DEBUG + if (le32_to_cpu(part->bam_cache[blk]) != old_addr) { + static int ne = 0; + if (++ne < 5) { + printk(KERN_NOTICE "ftl_cs: set_bam_entry() " + "inconsistency!\n"); + printk(KERN_NOTICE "ftl_cs: log_addr = 0x%x, cache" + " = 0x%x\n", + le32_to_cpu(part->bam_cache[blk]), old_addr); + } + return -EIO; + } +#endif + part->bam_cache[blk] = le_virt_addr; + } + ret = part->mbd.mtd->write(part->mbd.mtd, offset, sizeof(u_int32_t), + &retlen, (u_char *)&le_virt_addr); + + if (ret) { + printk(KERN_NOTICE "ftl_cs: set_bam_entry() failed!\n"); + printk(KERN_NOTICE "ftl_cs: log_addr = 0x%x, new = 0x%x\n", + log_addr, virt_addr); + } + return ret; +} /* set_bam_entry */ + +static int ftl_write(partition_t *part, caddr_t buffer, + u_long sector, u_long nblocks) +{ + u_int32_t bsize, log_addr, virt_addr, old_addr, blk; + u_long i; + int ret; + size_t retlen, offset; + + DEBUG(2, "ftl_cs: ftl_write(0x%p, %ld, %ld)\n", + part, sector, nblocks); + if (!(part->state & FTL_FORMATTED)) { + printk(KERN_NOTICE "ftl_cs: bad partition\n"); + return -EIO; + } + /* See if we need to reclaim space, before we start */ + while (part->FreeTotal < nblocks) { + ret = reclaim_block(part); + if (ret) + return ret; + } + + bsize = 1 << part->header.EraseUnitSize; + + virt_addr = sector * SECTOR_SIZE | BLOCK_DATA; + for (i = 0; i < nblocks; i++) { + if (virt_addr >= le32_to_cpu(part->header.FormattedSize)) { + printk(KERN_NOTICE "ftl_cs: bad write offset\n"); + return -EIO; + } + + /* Grab a free block */ + blk = find_free(part); + if (blk == 0) { + static int ne = 0; + if (++ne < 5) + printk(KERN_NOTICE "ftl_cs: internal error: " + "no free blocks!\n"); + return -ENOSPC; + } + + /* Tag the BAM entry, and write the new block */ + log_addr = part->bam_index * bsize + blk * SECTOR_SIZE; + part->EUNInfo[part->bam_index].Free--; + part->FreeTotal--; + if (set_bam_entry(part, log_addr, 0xfffffffe)) + return -EIO; + part->EUNInfo[part->bam_index].Deleted++; + offset = (part->EUNInfo[part->bam_index].Offset + + blk * SECTOR_SIZE); + ret = part->mbd.mtd->write(part->mbd.mtd, offset, SECTOR_SIZE, &retlen, + buffer); + + if (ret) { + printk(KERN_NOTICE "ftl_cs: block write failed!\n"); + printk(KERN_NOTICE "ftl_cs: log_addr = 0x%x, virt_addr" + " = 0x%x, Offset = 0x%zx\n", log_addr, virt_addr, + offset); + return -EIO; + } + + /* Only delete the old entry when the new entry is ready */ + old_addr = part->VirtualBlockMap[sector+i]; + if (old_addr != 0xffffffff) { + part->VirtualBlockMap[sector+i] = 0xffffffff; + part->EUNInfo[old_addr/bsize].Deleted++; + if (set_bam_entry(part, old_addr, 0)) + return -EIO; + } + + /* Finally, set up the new pointers */ + if (set_bam_entry(part, log_addr, virt_addr)) + return -EIO; + part->VirtualBlockMap[sector+i] = log_addr; + part->EUNInfo[part->bam_index].Deleted--; + + buffer += SECTOR_SIZE; + virt_addr += SECTOR_SIZE; + } + return 0; +} /* ftl_write */ + +static int ftl_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo) +{ + partition_t *part = (void *)dev; + u_long sect; + + /* Sort of arbitrary: round size down to 4KiB boundary */ + sect = le32_to_cpu(part->header.FormattedSize)/SECTOR_SIZE; + + geo->heads = 1; + geo->sectors = 8; + geo->cylinders = sect >> 3; + + return 0; +} + +static int ftl_readsect(struct mtd_blktrans_dev *dev, + unsigned long block, char *buf) +{ + return ftl_read((void *)dev, buf, block, 1); +} + +static int ftl_writesect(struct mtd_blktrans_dev *dev, + unsigned long block, char *buf) +{ + return ftl_write((void *)dev, buf, block, 1); +} + +/*====================================================================*/ + +void ftl_freepart(partition_t *part) +{ + if (part->VirtualBlockMap) { + vfree(part->VirtualBlockMap); + part->VirtualBlockMap = NULL; + } + if (part->VirtualPageMap) { + kfree(part->VirtualPageMap); + part->VirtualPageMap = NULL; + } + if (part->EUNInfo) { + kfree(part->EUNInfo); + part->EUNInfo = NULL; + } + if (part->XferInfo) { + kfree(part->XferInfo); + part->XferInfo = NULL; + } + if (part->bam_cache) { + kfree(part->bam_cache); + part->bam_cache = NULL; + } + +} /* ftl_freepart */ + +static void ftl_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd) +{ + partition_t *partition; + + partition = kmalloc(sizeof(partition_t), GFP_KERNEL); + + if (!partition) { + printk(KERN_WARNING "No memory to scan for FTL on %s\n", + mtd->name); + return; + } + + memset(partition, 0, sizeof(partition_t)); + + partition->mbd.mtd = mtd; + + if ((scan_header(partition) == 0) && + (build_maps(partition) == 0)) { + + partition->state = FTL_FORMATTED; +#ifdef PCMCIA_DEBUG + printk(KERN_INFO "ftl_cs: opening %d KiB FTL partition\n", + le32_to_cpu(partition->header.FormattedSize) >> 10); +#endif + partition->mbd.size = le32_to_cpu(partition->header.FormattedSize) >> 9; + partition->mbd.blksize = SECTOR_SIZE; + partition->mbd.tr = tr; + partition->mbd.devnum = -1; + if (!add_mtd_blktrans_dev((void *)partition)) + return; + } + + ftl_freepart(partition); + kfree(partition); +} + +static void ftl_remove_dev(struct mtd_blktrans_dev *dev) +{ + del_mtd_blktrans_dev(dev); + ftl_freepart((partition_t *)dev); + kfree(dev); +} + +struct mtd_blktrans_ops ftl_tr = { + .name = "ftl", + .major = FTL_MAJOR, + .part_bits = PART_BITS, + .readsect = ftl_readsect, + .writesect = ftl_writesect, + .getgeo = ftl_getgeo, + .add_mtd = ftl_add_mtd, + .remove_dev = ftl_remove_dev, + .owner = THIS_MODULE, +}; + +int init_ftl(void) +{ + DEBUG(0, "$Id: ftl.c,v 1.54 2004/11/16 18:33:15 dwmw2 Exp $\n"); + + return register_mtd_blktrans(&ftl_tr); +} + +static void __exit cleanup_ftl(void) +{ + deregister_mtd_blktrans(&ftl_tr); +} + +module_init(init_ftl); +module_exit(cleanup_ftl); + + +MODULE_LICENSE("Dual MPL/GPL"); +MODULE_AUTHOR("David Hinds <dahinds@users.sourceforge.net>"); +MODULE_DESCRIPTION("Support code for Flash Translation Layer, used on PCMCIA devices"); |
