nuttx/drivers/mtd/smart.c

2223 lines
65 KiB
C

/****************************************************************************
* drivers/mtd/smart.c
*
* Sector Mapped Allocation for Really Tiny (SMART) Flash block driver.
*
* Copyright (C) 2013 Ken Pettit. All rights reserved.
* Author: Ken Pettit <pettitkd@gmail.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <stdint.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <debug.h>
#include <errno.h>
#include <nuttx/kmalloc.h>
#include <nuttx/fs/fs.h>
#include <nuttx/fs/ioctl.h>
#include <nuttx/mtd.h>
#include <nuttx/smart.h>
/****************************************************************************
* Private Definitions
****************************************************************************/
#define SMART_STATUS_COMMITTED 0x80
#define SMART_STATUS_RELEASED 0x40
#define SMART_STATUS_SIZEBITS 0x1C
#define SMART_STATUS_VERBITS 0x03
#define SMART_STATUS_VERSION 0x01
#define SMART_SECTSIZE_256 0x00
#define SMART_SECTSIZE_512 0x04
#define SMART_SECTSIZE_1024 0x08
#define SMART_SECTSIZE_2048 0x0C
#define SMART_SECTSIZE_4096 0x10
#define SMART_SECTSIZE_8192 0x14
#define SMART_SECTSIZE_16384 0x18
#define SMART_FMT_STAT_UNKNOWN 0
#define SMART_FMT_STAT_FORMATTED 1
#define SMART_FMT_STAT_NOFMT 2
#define SMART_FMT_POS1 sizeof(struct smart_sect_header_s)
#define SMART_FMT_POS2 (SMART_FMT_POS1 + 1)
#define SMART_FMT_POS3 (SMART_FMT_POS1 + 2)
#define SMART_FMT_POS4 (SMART_FMT_POS1 + 3)
#define SMART_FMT_SIG1 'S'
#define SMART_FMT_SIG2 'M'
#define SMART_FMT_SIG3 'R'
#define SMART_FMT_SIG4 'T'
#define SMART_FMT_VERSION_POS (SMART_FMT_POS1 + 4)
#define SMART_FMT_NAMESIZE_POS (SMART_FMT_POS1 + 5)
#define SMART_FMT_ROOTDIRS_POS (SMART_FMT_POS1 + 6)
#define SMARTFS_FMT_AGING_POS 32
#define SMART_FMT_VERSION 1
#define SMART_FIRST_ALLOC_SECTOR 12 /* First logical sector number we will
* use for assignment of requested Alloc
* sectors. All enries below this are
* reserved (some for root dir entries,
* other for our use, such as format
* sector, etc. */
#if defined(CONFIG_FS_READAHEAD) || (defined(CONFIG_FS_WRITABLE) && defined(CONFIG_FS_WRITEBUFFER))
# define CONFIG_SMART_RWBUFFER 1
#endif
#ifndef CONFIG_MTD_SMART_SECTOR_SIZE
# define CONFIG_MTD_SMART_SECTOR_SIZE 1024
#endif
#ifndef offsetof
#define offsetof(type, member) ( (size_t) &( ( (type *) 0)->member))
#endif
/****************************************************************************
* Private Types
****************************************************************************/
struct smart_struct_s
{
FAR struct mtd_dev_s *mtd; /* Contained MTD interface */
struct mtd_geometry_s geo; /* Device geometry */
uint16_t neraseblocks; /* Number of erase blocks or sub-sectors */
uint16_t freesectors; /* Total number of free sectors */
uint16_t mtdBlksPerSector; /* Number of MTD blocks per SMART Sector */
uint16_t sectorsPerBlk; /* Number of sectors per erase block */
uint16_t sectorsize; /* Sector size on device */
uint16_t totalsectors; /* Total number of sectors on device */
FAR uint16_t *sMap; /* Virtual to physical sector map */
FAR uint8_t *releasecount; /* Count of released sectors per erase block */
FAR uint8_t *freecount; /* Count of free sectors per erase block */
FAR char *rwbuffer; /* Our sector read/write buffer */
const FAR char *partname; /* Optional partition name */
uint8_t formatversion; /* Format version on the device */
uint8_t formatstatus; /* Indicates the status of the device format */
uint8_t namesize; /* Length of filenames on this device */
#ifdef CONFIG_SMARTFS_MULTI_ROOT_DIRS
uint8_t rootdirentries; /* Number of root directory entries */
uint8_t minor; /* Minor number of the block entry */
#endif
};
#ifdef CONFIG_SMARTFS_MULTI_ROOT_DIRS
struct smart_multiroot_device_s
{
FAR struct smart_struct_s* dev;
uint8_t rootdirnum;
};
#endif
struct smart_sect_header_s
{
uint8_t logicalsector[2]; /* The logical sector number */
uint8_t seq[2]; /* Incrementing sequence number */
uint8_t status; /* Status of this sector:
* Bit 7: 1 = Not commited
* 0 = commited
* Bit 6: 1 = Not released
* 0 = released
* Bit 5: Reserved - 1
* Bit 4: Reserved - 1
* Bit 3: Reserved - 1
* Bit 2: Reserved - 1
* Bit 1-0: Format version */
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static int smart_open(FAR struct inode *inode);
static int smart_close(FAR struct inode *inode);
static ssize_t smart_reload(struct smart_struct_s *dev, FAR uint8_t *buffer,
off_t startblock, size_t nblocks);
static ssize_t smart_read(FAR struct inode *inode, unsigned char *buffer,
size_t start_sector, unsigned int nsectors);
#ifdef CONFIG_FS_WRITABLE
static ssize_t smart_write(FAR struct inode *inode, const unsigned char *buffer,
size_t start_sector, unsigned int nsectors);
#endif
static int smart_geometry(FAR struct inode *inode, struct geometry *geometry);
static int smart_ioctl(FAR struct inode *inode, int cmd, unsigned long arg);
/****************************************************************************
* Private Data
****************************************************************************/
static const struct block_operations g_bops =
{
smart_open, /* open */
smart_close, /* close */
smart_read, /* read */
#ifdef CONFIG_FS_WRITABLE
smart_write, /* write */
#else
NULL, /* write */
#endif
smart_geometry, /* geometry */
smart_ioctl /* ioctl */
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: smart_open
*
* Description: Open the block device
*
****************************************************************************/
static int smart_open(FAR struct inode *inode)
{
fvdbg("Entry\n");
return OK;
}
/****************************************************************************
* Name: smart_close
*
* Description: close the block device
*
****************************************************************************/
static int smart_close(FAR struct inode *inode)
{
fvdbg("Entry\n");
return OK;
}
/****************************************************************************
* Name: smart_reload
*
* Description: Read the specified numer of sectors
*
****************************************************************************/
static ssize_t smart_reload(struct smart_struct_s *dev, FAR uint8_t *buffer,
off_t startblock, size_t nblocks)
{
ssize_t nread;
ssize_t mtdBlocks, mtdStartBlock;
/* Calculate the number of MTD blocks to read */
mtdBlocks = nblocks * dev->mtdBlksPerSector;
/* Calculate the first MTD block number */
mtdStartBlock = startblock * dev->mtdBlksPerSector;
/* Read the full erase block into the buffer */
fdbg("Read %d blocks starting at block %d\n", mtdBlocks, mtdStartBlock);
nread = MTD_BREAD(dev->mtd, mtdStartBlock, mtdBlocks, buffer);
if (nread != mtdBlocks)
{
fdbg("Read %d blocks starting at block %d failed: %d\n",
nblocks, startblock, nread);
}
return nread;
}
/****************************************************************************
* Name: smart_read
*
* Description: Read the specified numer of sectors
*
****************************************************************************/
static ssize_t smart_read(FAR struct inode *inode, unsigned char *buffer,
size_t start_sector, unsigned int nsectors)
{
struct smart_struct_s *dev;
fvdbg("SMART: sector: %d nsectors: %d\n", start_sector, nsectors);
DEBUGASSERT(inode && inode->i_private);
#ifdef CONFIG_SMARTFS_MULTI_ROOT_DIRS
dev = ((struct smart_multiroot_device_s*) inode->i_private)->dev;
#else
dev = (struct smart_struct_s *)inode->i_private;
#endif
return smart_reload(dev, buffer, start_sector, nsectors);
}
/****************************************************************************
* Name: smart_write
*
* Description: Write (or buffer) the specified number of sectors
*
****************************************************************************/
#ifdef CONFIG_FS_WRITABLE
static ssize_t smart_write(FAR struct inode *inode, const unsigned char *buffer,
size_t start_sector, unsigned int nsectors)
{
struct smart_struct_s *dev;
off_t alignedblock;
off_t mask;
off_t blkstowrite;
off_t offset;
off_t nextblock;
off_t mtdBlksPerErase;
off_t eraseblock;
size_t remaining;
size_t nxfrd;
int ret;
off_t mtdstartblock, mtdblockcount;
fvdbg("sector: %d nsectors: %d\n", start_sector, nsectors);
DEBUGASSERT(inode && inode->i_private);
#ifdef CONFIG_SMARTFS_MULTI_ROOT_DIRS
dev = ((struct smart_multiroot_device_s*) inode->i_private)->dev;
#else
dev = (struct smart_struct_s *)inode->i_private;
#endif
/* I think maybe we need to lock on a mutex here */
/* Get the aligned block. Here is is assumed: (1) The number of R/W blocks
* per erase block is a power of 2, and (2) the erase begins with that same
* alignment.
*/
mask = dev->sectorsPerBlk - 1;
alignedblock = ((start_sector + mask) & ~mask) * dev->mtdBlksPerSector;
/* Convert SMART blocks into MTD blocks */
mtdstartblock = start_sector * dev->mtdBlksPerSector;
mtdblockcount = nsectors * dev->mtdBlksPerSector;
mtdBlksPerErase = dev->mtdBlksPerSector * dev->sectorsPerBlk;
fvdbg("mtdsector: %d mtdnsectors: %d\n", mtdstartblock, mtdblockcount);
/* Start at first block to be written */
remaining = mtdblockcount;
nextblock = mtdstartblock;
offset = 0;
/* Loop for all blocks to be written */
while (remaining > 0)
{
/* If this is an aligned block, then erase the block */
if (alignedblock == nextblock)
{
/* Erase the erase block */
eraseblock = alignedblock / mtdBlksPerErase;
ret = MTD_ERASE(dev->mtd, eraseblock, 1);
if (ret < 0)
{
fdbg("Erase block=%d failed: %d\n", eraseblock, ret);
/* Unlock the mutex if we add one */
return ret;
}
}
/* Calculate the number of blocks to write. */
blkstowrite = mtdBlksPerErase;
if (nextblock != alignedblock)
{
blkstowrite = alignedblock - nextblock;
}
if (blkstowrite > remaining)
{
blkstowrite = remaining;
}
/* Try to write to the sector. */
fdbg("Write MTD block %d from offset %d\n", nextblock, offset);
nxfrd = MTD_BWRITE(dev->mtd, nextblock, blkstowrite, &buffer[offset]);
if (nxfrd != blkstowrite)
{
/* The block is not empty!! What to do? */
fdbg("Write block %d failed: %d.\n", nextblock, nxfrd);
/* Unlock the mutex if we add one */
return -EIO;
}
/* Then update for amount written */
nextblock += blkstowrite;
remaining -= blkstowrite;
offset += blkstowrite * dev->geo.blocksize;
alignedblock += mtdBlksPerErase;
}
return nsectors;
}
#endif /* CONFIG_FS_WRITABLE */
/****************************************************************************
* Name: smart_geometry
*
* Description: Return device geometry
*
****************************************************************************/
static int smart_geometry(FAR struct inode *inode, struct geometry *geometry)
{
struct smart_struct_s *dev;
uint32_t erasesize;
fvdbg("Entry\n");
DEBUGASSERT(inode);
if (geometry)
{
#ifdef CONFIG_SMARTFS_MULTI_ROOT_DIRS
dev = ((struct smart_multiroot_device_s*) inode->i_private)->dev;
#else
dev = (struct smart_struct_s *)inode->i_private;
#endif
geometry->geo_available = true;
geometry->geo_mediachanged = false;
#ifdef CONFIG_FS_WRITABLE
geometry->geo_writeenabled = true;
#else
geometry->geo_writeenabled = false;
#endif
erasesize = dev->geo.erasesize;
if (erasesize == 0)
{
erasesize = 65536;
}
geometry->geo_nsectors = dev->geo.neraseblocks * erasesize /
dev->sectorsize;
geometry->geo_sectorsize = dev->sectorsize;
fvdbg("available: true mediachanged: false writeenabled: %s\n",
geometry->geo_writeenabled ? "true" : "false");
fvdbg("nsectors: %d sectorsize: %d\n",
geometry->geo_nsectors, geometry->geo_sectorsize);
return OK;
}
return -EINVAL;
}
/****************************************************************************
* Name: smart_setsectorsize
*
* Description: Sets the device's sector size and recalculates sector size
* dependant variables.
*
****************************************************************************/
static int smart_setsectorsize(struct smart_struct_s *dev, uint16_t size)
{
uint32_t erasesize;
uint32_t totalsectors;
/* Validate the size isn't zero so we don't divide by zero below */
if (size == 0)
{
size = CONFIG_MTD_SMART_SECTOR_SIZE;
}
erasesize = dev->geo.erasesize;
dev->neraseblocks = dev->geo.neraseblocks;
/* Most FLASH devices have erase size of 64K, but geo.erasesize is only
* 16 bits, so it will be zero
*/
if (erasesize == 0)
{
erasesize = 65536;
}
dev->sectorsize = size;
dev->mtdBlksPerSector = dev->sectorsize / dev->geo.blocksize;
dev->sectorsPerBlk = erasesize / dev->sectorsize;
/* Release any existing rwbuffer and sMap */
if (dev->sMap != NULL)
{
kfree(dev->sMap);
}
if (dev->rwbuffer != NULL)
{
kfree(dev->rwbuffer);
}
/* Allocate a virtual to physical sector map buffer. Also allocate
* the storage space for releasecount and freecounts.
*/
totalsectors = dev->neraseblocks * dev->sectorsPerBlk;
dev->totalsectors = (uint16_t) totalsectors;
dev->sMap = (uint16_t *) kmalloc(totalsectors * sizeof(uint16_t) +
(dev->neraseblocks << 1));
if (!dev->sMap)
{
fdbg("Error allocating SMART virtual map buffer\n");
kfree(dev);
return -EINVAL;
}
dev->releasecount = (uint8_t *) dev->sMap + (totalsectors * sizeof(uint16_t));
dev->freecount = dev->releasecount + dev->neraseblocks;
/* Allocate a read/write buffer */
dev->rwbuffer = (char *) kmalloc(size);
if (!dev->rwbuffer)
{
fdbg("Error allocating SMART read/write buffer\n");
kfree(dev->sMap);
kfree(dev);
return -EINVAL;
}
return OK;
}
/****************************************************************************
* Name: smart_bytewrite
*
* Description: Writes a non-page size count of bytes to the underlying
* MTD device. If the MTD driver supports a direct impl of
* write, then it uses it, otherwise it does a read-modify-write
* and depends on the architecture of the flash to only program
* bits that acutally changed.
*
****************************************************************************/
static ssize_t smart_bytewrite(struct smart_struct_s *dev, size_t offset,
int nbytes, const uint8_t *buffer)
{
ssize_t ret;
#ifdef CONFIG_MTD_BYTE_WRITE
/* Check if the underlying MTD device supports write */
if (dev->mtd->write != NULL)
{
/* Use the MTD's write method to write individual bytes */
ret = dev->mtd->write(dev->mtd, offset, nbytes, buffer);
}
else
#endif
{
/* Perform block-based read-modify-write */
uint16_t startblock;
uint16_t nblocks;
/* First calculate the start block and number of blocks affected */
startblock = offset / dev->geo.blocksize;
nblocks = (nbytes + dev->geo.blocksize-1) / dev->geo.blocksize;
DEBUGASSERT(nblocks <= dev->mtdBlksPerSector);
/* Do a block read */
ret = MTD_BREAD(dev->mtd, startblock, nblocks, (uint8_t *) dev->rwbuffer);
if (ret < 0)
{
fdbg("Error %d reading from device\n", -ret);
goto errout;
}
/* Modify the data */
memcpy(&dev->rwbuffer[offset - startblock * dev->geo.blocksize], buffer, nbytes);
/* Write the data back to the device */
ret = MTD_BWRITE(dev->mtd, startblock, nblocks, (uint8_t *) dev->rwbuffer);
if (ret < 0)
{
fdbg("Error %d writing to device\n", -ret);
goto errout;
}
}
ret = nbytes;
errout:
return ret;
}
/****************************************************************************
* Name: smart_scan
*
* Description: Performs a scan of the MTD device searching for format
* information and fills in logical sector mapping, freesector
* count, etc.
*
****************************************************************************/
static int smart_scan(struct smart_struct_s *dev)
{
int sector;
int ret;
int offset;
uint16_t totalsectors;
uint16_t sectorsize;
uint16_t logicalsector;
uint16_t seq1;
uint16_t seq2;
size_t readaddress;
struct smart_sect_header_s header;
#ifdef CONFIG_SMARTFS_MULTI_ROOT_DIRS
int x;
char devname[22];
struct smart_multiroot_device_s *rootdirdev;
#endif
fvdbg("Entry\n");
/* Read the 1st header from the device. We always keep the
* 1st sector's header's sectorsize field accurate, even
* after we erase an MTD block/sector */
ret = MTD_READ(dev->mtd, 0, sizeof(struct smart_sect_header_s),
(uint8_t *) &header);
if (ret != sizeof(struct smart_sect_header_s))
{
goto err_out;
}
/* Now set the sectorsize and other sectorsize derived variables */
if (header.status == CONFIG_SMARTFS_ERASEDSTATE)
{
sectorsize = CONFIG_MTD_SMART_SECTOR_SIZE;
}
else
{
sectorsize = (header.status & SMART_STATUS_SIZEBITS) << 7;
}
ret = smart_setsectorsize(dev, sectorsize);
if (ret != OK)
{
goto err_out;
}
/* Initialize the device variables */
totalsectors = dev->neraseblocks * dev->sectorsPerBlk;
dev->formatstatus = SMART_FMT_STAT_NOFMT;
dev->freesectors = totalsectors;
/* Initialize the freecount and releasecount arrays */
for (sector = 0; sector < dev->neraseblocks; sector++)
{
dev->freecount[sector] = dev->sectorsPerBlk;
dev->releasecount[sector] = 0;
}
/* Initialize the sector map */
for (sector = 0; sector < totalsectors; sector++)
{
dev->sMap[sector] = -1;
}
/* Now scan the MTD device */
for (sector = 0; sector < totalsectors; sector++)
{
fvdbg("Scan sector %d\n", sector);
/* Calculate the read address for this sector */
readaddress = sector * dev->mtdBlksPerSector * dev->geo.blocksize;
/* Read the header for this sector */
ret = MTD_READ(dev->mtd, readaddress, sizeof(struct smart_sect_header_s),
(uint8_t *) &header);
if (ret != sizeof(struct smart_sect_header_s))
{
goto err_out;
}
/* Get the logical sector number for this physical sector */
logicalsector = *((uint16_t *) header.logicalsector);
#if CONFIG_SMARTFS_ERASEDSTATE == 0x00
if (logicalsector == 0)
{
logicalsector = -1;
}
#endif
/* Test if this sector has been committed */
if ((header.status & SMART_STATUS_COMMITTED) ==
(CONFIG_SMARTFS_ERASEDSTATE & SMART_STATUS_COMMITTED))
{
continue;
}
/* This block is commited, therefore not free. Update the
* erase block's freecount.
*/
dev->freecount[sector / dev->sectorsPerBlk]--;
dev->freesectors--;
/* Test if this sector has been release and if it has,
* update the erase block's releasecount.
*/
if ((header.status & SMART_STATUS_RELEASED) !=
(CONFIG_SMARTFS_ERASEDSTATE & SMART_STATUS_RELEASED))
{
dev->releasecount[sector / dev->sectorsPerBlk]++;
continue;
}
if ((header.status & SMART_STATUS_VERBITS) != SMART_STATUS_VERSION)
{
continue;
}
/* Validate the logical sector number is in bounds */
if (logicalsector >= totalsectors)
{
/* Error in logical sector read from the MTD device */
fdbg("Invalid logical sector %d at physical %d.\n",
logicalsector, sector);
continue;
}
/* If this is logical sector zero, then read in the signature
* information to validate the format signature.
*/
if (logicalsector == 0)
{
/* Read the sector data */
ret = MTD_READ(dev->mtd, readaddress, 32,
(uint8_t*) dev->rwbuffer);
if (ret != 32)
{
fdbg("Error reading physical sector %d.\n", sector);
goto err_out;
}
/* Validate the format signature */
if (dev->rwbuffer[SMART_FMT_POS1] != SMART_FMT_SIG1 ||
dev->rwbuffer[SMART_FMT_POS2] != SMART_FMT_SIG2 ||
dev->rwbuffer[SMART_FMT_POS3] != SMART_FMT_SIG3 ||
dev->rwbuffer[SMART_FMT_POS4] != SMART_FMT_SIG4)
{
/* Invalid signature on a sector claiming to be sector 0!
* What should we do? Release it?*/
continue;
}
/* TODO: May want to validate / save the erase block aging info */
/* Mark the volume as formatted and set the sector size */
dev->formatstatus = SMART_FMT_STAT_FORMATTED;
dev->namesize = dev->rwbuffer[SMART_FMT_NAMESIZE_POS];
dev->formatversion = dev->rwbuffer[SMART_FMT_VERSION_POS];
#ifdef CONFIG_SMARTFS_MULTI_ROOT_DIRS
dev->rootdirentries = dev->rwbuffer[SMART_FMT_ROOTDIRS_POS];
/* If rootdirentries is greater than 1, then we need to register
* additional block devices.
*/
for (x = 1; x < dev->rootdirentries; x++)
{
if (dev->partname != NULL)
{
snprintf(dev->rwbuffer, sizeof(devname), "/dev/smart%d%s%d",
dev->minor, dev->partname, x+1);
}
else
{
snprintf(devname, sizeof(devname), "/dev/smart%dd%d", dev->minor,
x + 1);
}
/* Inode private data is a reference to a struct containing
* the SMART device structure and the root directory number.
*/
rootdirdev = (struct smart_multiroot_device_s*) kmalloc(sizeof(*rootdirdev));
if (rootdirdev == NULL)
{
fdbg("Memory alloc failed\n");
ret = -ENOMEM;
goto err_out;
}
/* Populate the rootdirdev */
rootdirdev->dev = dev;
rootdirdev->rootdirnum = x;
ret = register_blockdriver(dev->rwbuffer, &g_bops, 0, rootdirdev);
/* Inode private data is a reference to the SMART device structure */
ret = register_blockdriver(devname, &g_bops, 0, rootdirdev);
}
#endif
}
/* Test for duplicate logical sectors on the device */
if (dev->sMap[logicalsector] != 0xFFFF)
{
/* Uh-oh, we found more than 1 physical sector claiming to be
* the * same logical sector. Use the sequence number information
* to resolve who wins.
*/
uint16_t loser;
seq2 = *((uint16_t *) header.seq);
/* We must re-read the 1st physical sector to get it's seq number */
readaddress = dev->sMap[logicalsector] * dev->mtdBlksPerSector * dev->geo.blocksize;
ret = MTD_READ(dev->mtd, readaddress, sizeof(struct smart_sect_header_s),
(uint8_t *) &header);
if (ret != sizeof(struct smart_sect_header_s))
{
goto err_out;
}
seq1 = *((uint16_t *) header.seq);
/* Now determine who wins */
if (seq1 > 0xFFF0 && seq2 < 10)
{
/* Seq 2 is the winner ... we assume it wrapped */
loser = dev->sMap[logicalsector];
dev->sMap[logicalsector] = sector;
}
else if (seq2 > seq1)
{
/* Seq 2 is bigger, so it's the winner */
loser = dev->sMap[logicalsector];
dev->sMap[logicalsector] = sector;
}
else
{
/* We keep the original mapping and seq2 is the loser */
loser = sector;
}
/* Now release the loser sector */
readaddress = loser * dev->mtdBlksPerSector * dev->geo.blocksize;
ret = MTD_READ(dev->mtd, readaddress, sizeof(struct smart_sect_header_s),
(uint8_t *) &header);
if (ret != sizeof(struct smart_sect_header_s))
{
goto err_out;
}
#if CONFIG_SMARTFS_ERASEDSTATE == 0xFF
header.status &= ~SMART_STATUS_RELEASED;
#else
header.status |= SMART_STATUS_RELEASED;
#endif
offset = readaddress + offsetof(struct smart_sect_header_s, status);
ret = smart_bytewrite(dev, offset, 1, &header.status);
if (ret < 0)
{
fdbg("Error %d releasing duplicate sector\n", -ret);
goto err_out;
}
}
/* Update the logical to physical sector map */
dev->sMap[logicalsector] = sector;
}
fdbg("SMART Scan\n");
fdbg(" Erase size: %10d\n", dev->sectorsPerBlk * dev->sectorsize);
fdbg(" Erase count: %10d\n", dev->neraseblocks);
fdbg(" Sect/block: %10d\n", dev->sectorsPerBlk);
fdbg(" MTD Blk/Sect: %10d\n", dev->mtdBlksPerSector);
ret = OK;
err_out:
return ret;
}
/****************************************************************************
* Name: smart_getformat
*
* Description: Populates the SMART format structure based on the format
* information for the inode.
*
****************************************************************************/
#ifdef CONFIG_SMARTFS_MULTI_ROOT_DIRS
static inline int smart_getformat(struct smart_struct_s *dev,
struct smart_format_s *fmt,
uint8_t rootdirnum)
#else
static inline int smart_getformat(struct smart_struct_s *dev,
struct smart_format_s *fmt)
#endif
{
int ret;
int x;
fvdbg("Entry\n");
DEBUGASSERT(fmt);
/* Test if we know the format status or not. If we don't know the
* status, then we must perform a scan of the device to search
* for the format marker
*/
if (dev->formatstatus != SMART_FMT_STAT_FORMATTED)
{
/* Perform the scan */
ret = smart_scan(dev);
if (ret != OK)
{
goto err_out;
}
}
/* Now fill in the structure */
if (dev->formatstatus == SMART_FMT_STAT_FORMATTED)
{
fmt->flags = SMART_FMT_ISFORMATTED;
}
else
{
fmt->flags = 0;
}
fmt->sectorsize = dev->sectorsize;
fmt->availbytes = dev->sectorsize - sizeof(struct smart_sect_header_s);
fmt->nsectors = dev->neraseblocks * dev->sectorsPerBlk;
fmt->nfreesectors = dev->freesectors;
fmt->namesize = dev->namesize;
#ifdef CONFIG_SMARTFS_MULTI_ROOT_DIRS
fmt->nrootdirentries = dev->rootdirentries;
fmt->rootdirnum = rootdirnum;
#endif
/* Add the released sectors to the reported free sector count */
for (x = 0; x < dev->neraseblocks; x++)
{
fmt->nfreesectors += dev->releasecount[x];
}
/* Subtract the reserved sector count */
fmt->nfreesectors -= dev->sectorsPerBlk + 4;
ret = OK;
err_out:
return ret;
}
/****************************************************************************
* Name: smart_llformat
*
* Description: Performs a low-level format of the flash device. This
* involves erasing the device and writing a valid sector
* zero (logical) with proper format signature.
*
****************************************************************************/
#ifdef CONFIG_FS_WRITABLE
static inline int smart_llformat(struct smart_struct_s *dev, unsigned long arg)
{
struct smart_sect_header_s *sectorheader;
size_t wrcount;
size_t totalsectors;
int x;
int ret;
uint8_t sectsize;
fvdbg("Entry\n");
/* Erase the MTD device */
ret = MTD_IOCTL(dev->mtd, MTDIOC_BULKERASE, 0);
if (ret < 0)
{
return ret;
}
/* Now construct a logical sector zero header to write to the device.
* We fill it with zero so when we add sector aging, all the sector
* ages will already be initialized to zero without needing special
* logic to deal with a 0xFF erased-state value.
*/
sectorheader = (struct smart_sect_header_s *) dev->rwbuffer;
memset(dev->rwbuffer, 0, dev->sectorsize);
memset(dev->rwbuffer, CONFIG_SMARTFS_ERASEDSTATE, SMARTFS_FMT_AGING_POS);
*((uint16_t *) sectorheader->seq) = 0;
sectsize = (CONFIG_MTD_SMART_SECTOR_SIZE >> 9) << 2;
#if ( CONFIG_SMARTFS_ERASEDSTATE == 0xFF )
*((uint16_t *) sectorheader->logicalsector) = 0;
sectorheader->status = (uint8_t) ~(SMART_STATUS_COMMITTED | SMART_STATUS_VERBITS |
SMART_STATUS_SIZEBITS) | SMART_STATUS_VERSION |
sectsize;
#else
*((uint16_t *) sectorheader->logicalsector) = 0xFFFF;
sectorheader->status = (uint8_t) (SMART_STATUS_COMMITTED | SMART_STATUS_VERSION |
sectsize);
#endif
/* Now add the format signature to the sector */
dev->rwbuffer[SMART_FMT_POS1] = SMART_FMT_SIG1;
dev->rwbuffer[SMART_FMT_POS2] = SMART_FMT_SIG2;
dev->rwbuffer[SMART_FMT_POS3] = SMART_FMT_SIG3;
dev->rwbuffer[SMART_FMT_POS4] = SMART_FMT_SIG4;
dev->rwbuffer[SMART_FMT_VERSION_POS] = SMART_FMT_VERSION;
dev->rwbuffer[SMART_FMT_NAMESIZE_POS] = CONFIG_SMARTFS_MAXNAMLEN;
/* Record the number of root directory entries we have */
dev->rwbuffer[SMART_FMT_ROOTDIRS_POS] = (uint8_t) arg;
/* Write the sector to the flash */
wrcount = MTD_BWRITE(dev->mtd, 0, dev->mtdBlksPerSector,
(uint8_t *) dev->rwbuffer);
if (wrcount != dev->mtdBlksPerSector)
{
/* The block is not empty!! What to do? */
fdbg("Write block 0 failed: %d.\n", wrcount);
/* Unlock the mutex if we add one */
return -EIO;
}
/* Now initialize our internal control variables */
ret = smart_setsectorsize(dev, CONFIG_MTD_SMART_SECTOR_SIZE);
if (ret != OK)
{
return ret;
}
dev->formatstatus = SMART_FMT_STAT_UNKNOWN;
dev->freesectors = dev->neraseblocks * dev->sectorsPerBlk - 1;
for (x = 0; x < dev->neraseblocks; x++)
{
/* Initialize the released and free counts */
dev->releasecount[x] = 0;
dev->freecount[x] = dev->sectorsPerBlk;
}
/* Account for the format sector */
dev->freecount[0]--;
/* Now initialize the logical to physical sector map */
dev->sMap[0] = 0; /* Logical sector zero = physical sector 0 */
totalsectors = dev->neraseblocks * dev->sectorsPerBlk;
for (x = 1; x < totalsectors; x++)
{
/* Mark all other logical sectors as non-existant */
dev->sMap[x] = -1;
}
#ifdef CONFIG_SMARTFS_MULTI_ROOT_DIRS
/* Un-register any extra directory device entries */
for (x = 2; x < 8; x++)
{
snprintf(dev->rwbuffer, 18, "/dev/smart%dd%d", dev->minor, x);
unregister_blockdriver(dev->rwbuffer);
}
#endif
return OK;
}
#endif /* CONFIG_FS_WRITABLE */
/****************************************************************************
* Name: smart_findfreephyssector
*
* Description: Finds a free physical sector based on free and released
* count logic, taking into account reserved sectors.
*
****************************************************************************/
static int smart_findfreephyssector(struct smart_struct_s *dev)
{
uint16_t allocfreecount;
uint16_t allocblock;
uint16_t physicalsector;
uint16_t x;
uint32_t readaddr;
struct smart_sect_header_s header;
int ret;
/* Determine which erase block we should allocate the new
* sector from. This is based on the number of free sectors
* available in each erase block. */
allocfreecount = 0;
allocblock = 0xFFFF;
physicalsector = 0xFFFF;
for (x = 0; x < dev->neraseblocks; x++)
{
/* Test if this block has more free blocks than the
* currently selected block */
if (dev->freecount[x] > allocfreecount)
{
/* Assign this block to alloc from */
allocblock = x;
allocfreecount = dev->freecount[x];
}
}
/* Check if we found an allocblock. */
if (allocblock == 0xFFFF)
{
/* No free sectors found! Bug? */
return -EIO;
}
/* Now find a free physical sector within this selected
* erase block to allocate. */
for (x = allocblock * dev->sectorsPerBlk;
x < (allocblock+1) * dev->sectorsPerBlk; x++)
{
/* Check if this physical sector is available */
readaddr = x * dev->mtdBlksPerSector * dev->geo.blocksize;
ret = MTD_READ(dev->mtd, readaddr, sizeof(struct smart_sect_header_s),
(uint8_t *) &header);
if (ret != sizeof(struct smart_sect_header_s))
{
fvdbg("Error reading phys sector %d\n", physicalsector);
return -EIO;
}
if ((*((uint16_t *) header.logicalsector) == 0xFFFF) &&
(*((uint16_t *) header.seq) == 0xFFFF) &&
((header.status & SMART_STATUS_COMMITTED) ==
(CONFIG_SMARTFS_ERASEDSTATE & SMART_STATUS_COMMITTED)))
{
physicalsector = x;
break;
}
}
return physicalsector;
}
/****************************************************************************
* Name: smart_garbagecollect
*
* Description: Performs garbage collection if needed. This is determined
* by the count of released sectors relative to free and
* total sectors.
*
****************************************************************************/
#ifdef CONFIG_FS_WRITABLE
static int smart_garbagecollect(struct smart_struct_s *dev)
{
uint16_t releasedsectors;
uint16_t collectblock;
uint16_t releasemax;
uint16_t newsector;
bool collect = TRUE;
int x;
int ret;
size_t offset;
struct smart_sect_header_s *header;
uint8_t newstatus;
while (collect)
{
collect = FALSE;
/* Calculate the number of released sectors on the device */
releasedsectors = 0;
collectblock = 0xFFFF;
releasemax = 0;
for (x = 0; x < dev->neraseblocks; x++)
{
releasedsectors += dev->releasecount[x];
if (dev->releasecount[x] > releasemax)
{
releasemax = dev->releasecount[x];
collectblock = x;
}
}
/* Test if the released sectors count is greater than the
* free sectors. If it is, then we will do garbage collection.
*/
if (releasedsectors > dev->freesectors)
collect = TRUE;
/* Test if we have more reached our reserved free sector limit */
if (dev->freesectors <= (dev->sectorsPerBlk << 0) + 4)
collect = TRUE;
/* Test if we need to garbage collect */
if (collect)
{
if (collectblock == 0xFFFF)
{
/* Need to collect, but no sectors with released blocks! */
ret = -ENOSPC;
goto errout;
}
fdbg("Collecting block %d, free=%d released=%d\n",
collectblock, dev->freecount[collectblock],
dev->releasecount[collectblock]);
if (dev->freecount[collectblock] == 6)
{
fdbg("here!\n");
}
/* Perform collection on block with the most released sectors.
* First mark the block as having no free sectors so we don't
* try to move sectors into the block we are trying to erase.
*/
dev->freecount[collectblock] = 0;
/* Next move all live data in the block to a new home. */
for (x = collectblock * dev->sectorsPerBlk; x <
(collectblock + 1) * dev->sectorsPerBlk; x++)
{
/* Read the next sector from this erase block */
ret = MTD_BREAD(dev->mtd, x * dev->mtdBlksPerSector,
dev->mtdBlksPerSector, (uint8_t *) dev->rwbuffer);
if (ret != dev->mtdBlksPerSector)
{
fdbg("Error reading sector %d\n", x);
ret = -EIO;
goto errout;
}
/* Test if if the block is in use */
header = (struct smart_sect_header_s *) dev->rwbuffer;
if (((header->status & SMART_STATUS_COMMITTED) ==
(CONFIG_SMARTFS_ERASEDSTATE & SMART_STATUS_COMMITTED)) ||
((header->status & SMART_STATUS_RELEASED) !=
(CONFIG_SMARTFS_ERASEDSTATE & SMART_STATUS_RELEASED)))
{
/* This sector doesn't have live data (free or released).
* just continue to the next sector and don't move it.
*/
continue;
}
/* Find a new sector where it can live, NOT in this erase block */
newsector = smart_findfreephyssector(dev);
if (newsector == 0xFFFF)
{
/* Unable to find a free sector!!! */
fdbg("Can't find a free sector for relocation\n");
ret = -EIO;
goto errout;
}
/* Increment the sequence number and clear the "commit" flag */
(*((uint16_t *) header->seq))++;
if (*((uint16_t *) header->seq) == 0xFFFF)
{
*((uint16_t *) header->seq) = 1;
}
#if CONFIG_SMARTFS_ERASEDSTATE == 0xFF
header->status |= SMART_STATUS_COMMITTED;
#else
header->status &= ~SMART_STATUS_COMMITTED;
#endif
/* Write the data to the new physical sector location */
ret = MTD_BWRITE(dev->mtd, newsector * dev->mtdBlksPerSector,
dev->mtdBlksPerSector, (uint8_t *) dev->rwbuffer);
/* Commit the sector */
offset = newsector * dev->mtdBlksPerSector * dev->geo.blocksize +
offsetof(struct smart_sect_header_s, status);
#if CONFIG_SMARTFS_ERASEDSTATE == 0xFF
newstatus = header->status & ~SMART_STATUS_COMMITTED;
#else
newstatus = header->status | SMART_STATUS_COMMITTED;
#endif
ret = smart_bytewrite(dev, offset, 1, &newstatus);
if (ret < 0)
{
fdbg("Error %d committing new sector %d\n" -ret, newsector);
goto errout;
}
/* Release the old physical sector */
#if CONFIG_SMARTFS_ERASEDSTATE == 0xFF
newstatus = header->status & ~SMART_STATUS_RELEASED;
#else
newstatus = header->status | SMART_STATUS_RELEASED;
#endif
offset = x * dev->mtdBlksPerSector * dev->geo.blocksize +
offsetof(struct smart_sect_header_s, status);
ret = smart_bytewrite(dev, offset, 1, &newstatus);
if (ret < 0)
{
fdbg("Error %d releasing old sector %d\n" -ret, x);
goto errout;
}
/* Update the variables */
dev->sMap[*((uint16_t *) header->logicalsector)] = newsector;
dev->freecount[newsector / dev->sectorsPerBlk]--;
}
/* Now erase the erase block */
MTD_ERASE(dev->mtd, collectblock, 1);
dev->freesectors += dev->releasecount[collectblock];
dev->freecount[collectblock] = dev->sectorsPerBlk;
dev->releasecount[collectblock] = 0;
/* If this is block zero, then be sure to write the sector size */
if (collectblock == 0)
{
/* Set the sector size in the 1st header */
uint8_t sectsize = dev->sectorsize >> 7;
#if ( CONFIG_SMARTFS_ERASEDSTATE == 0xFF )
newstatus = (uint8_t) ~SMART_STATUS_SIZEBITS | sectsize;
#else
newstatus = (uint8_t) sectsize;
#endif
/* Write the sector size to the device */
offset = offsetof(struct smart_sect_header_s, status);
ret = smart_bytewrite(dev, offset, 1, &newstatus);
if (ret < 0)
{
fdbg("Error %d setting sector 0 size\n", -ret);
}
}
/* Update the block aging information in the format signature sector */
}
else
{
/* Test for aging sectors and push them to a new location
* so we wear evenly.
*/
}
}
return OK;
errout:
return ret;
}
#endif /* CONFIG_FS_WRITABLE */
/****************************************************************************
* Name: smart_writesector
*
* Description: Writes data to the specified logical sector. The sector
* should have already been allocated prior to the write. If
* the logical sector already has data on the device, it will
* be released and a new physical sector will be created and
* mapped to the logical sector.
*
****************************************************************************/
#ifdef CONFIG_FS_WRITABLE
static inline int smart_writesector(struct smart_struct_s *dev, unsigned long arg)
{
int ret;
uint16_t x;
bool needsrelocate = FALSE;
uint16_t mtdblock;
uint16_t physsector;
struct smart_read_write_s *req;
struct smart_sect_header_s *header;
size_t offset;
uint8_t byte;
fvdbg("Entry\n");
req = (struct smart_read_write_s *) arg;
DEBUGASSERT(req->offset <= dev->sectorsize);
DEBUGASSERT(req->offset+req->count <= dev->sectorsize);
/* Ensure the logical sector has been allocated */
if (req->logsector >= dev->totalsectors)
{
fdbg("Logical sector %d too large\n", req->logsector);
ret = -EINVAL;
goto errout;
}
physsector = dev->sMap[req->logsector];
if (physsector == 0xFFFF)
{
fdbg("Logical sector %d not allocated\n", req->logsector);
ret = -EINVAL;
goto errout;
}
/* Read the sector data into our buffer */
mtdblock = physsector * dev->mtdBlksPerSector;
ret = MTD_BREAD(dev->mtd, mtdblock, dev->mtdBlksPerSector, (uint8_t *)
dev->rwbuffer);
if (ret != dev->mtdBlksPerSector)
{
fdbg("Error reading phys sector %d\n", physsector);
ret = -EIO;
goto errout;
}
/* Test if we need to relocate the sector to perform the write */
for (x = 0; x < req->count; x++)
{
/* Test if the next byte can be written to the flash */
byte = dev->rwbuffer[sizeof(struct smart_sect_header_s) + req->offset + x];
#if CONFIG_SMARTFS_ERASEDSTATE == 0xFF
if (((byte ^ req->buffer[x]) | byte) != byte)
{
needsrelocate = TRUE;
break;
}
#else
if (((byte ^ req->buffer[x]) | req->buffer[x]) != req->buffer[x])
{
needsrelocate = TRUE;
break;
}
#endif
}
if (needsrelocate)
{
/* Find a new physical sector to save data to */
physsector = smart_findfreephyssector(dev);
if (physsector == 0xFFFF)
{
fdbg("Error relocating sector %d\n", req->logsector);
ret = -EIO;
goto errout;
}
/* Update the sequence number to indicate the sector was moved */
header = (struct smart_sect_header_s *) dev->rwbuffer;
(*((uint16_t *) header->seq))++;
#if CONFIG_SMARTFS_ERASEDSTATE == 0xFF
header->status |= SMART_STATUS_COMMITTED;
#else
header->status &= SMART_STATUS_COMMITTED;
#endif
}
/* Now copy the data to the sector buffer. */
memcpy(&dev->rwbuffer[sizeof(struct smart_sect_header_s) + req->offset],
req->buffer, req->count);
/* Now write the sector buffer to the device. */
if (needsrelocate)
{
/* Write the entire sector to the new physical location, uncommitted. */
ret = MTD_BWRITE(dev->mtd, physsector * dev->mtdBlksPerSector,
dev->mtdBlksPerSector, (uint8_t *) dev->rwbuffer);
if (ret != dev->mtdBlksPerSector)
{
fdbg("Error writing to physical sector %d\n", physsector);
ret = -EIO;
goto errout;
}
/* Commit the new physical sector */
#if CONFIG_SMARTFS_ERASEDSTATE == 0xFF
byte = header->status & ~SMART_STATUS_COMMITTED;
#else
byte = header->status | SMART_STATUS_COMMITTED;
#endif
offset = physsector * dev->mtdBlksPerSector * dev->geo.blocksize +
offsetof(struct smart_sect_header_s, status);
ret = smart_bytewrite(dev, offset, 1, &byte);
if (ret != 1)
{
fvdbg("Error committing physical sector %d\n", physsector);
ret = -EIO;
goto errout;
}
/* Release the old physical sector */
#if CONFIG_SMARTFS_ERASEDSTATE == 0xFF
byte = header->status & ~SMART_STATUS_RELEASED;
#else
byte = header->status | SMART_STATUS_RELEASED;
#endif
offset = mtdblock * dev->geo.blocksize +
offsetof(struct smart_sect_header_s, status);
ret = smart_bytewrite(dev, offset, 1, &byte);
/* Update releasecount for released sector and freecount for the
* newly allocated physical sector. */
dev->releasecount[dev->sMap[req->logsector] / dev->sectorsPerBlk]++;
dev->freecount[physsector / dev->sectorsPerBlk]--;
dev->freesectors--;
/* Update the sector map */
dev->sMap[req->logsector] = physsector;
/* Since we performed a relocation, do garbage collection to
* ensure we don't fill up our flash with released blocks.
*/
smart_garbagecollect(dev);
}
else
{
/* Not relocated. Just write the portion of the sector that needs
* to be written. */
offset = mtdblock * dev->geo.blocksize +
sizeof(struct smart_sect_header_s) + req->offset;
ret = smart_bytewrite(dev, offset, req->count, req->buffer);
}
ret = OK;
errout:
return ret;
}
#endif /* CONFIG_FS_WRITABLE */
/****************************************************************************
* Name: smart_readsector
*
* Description: Reads data from the specified logical sector. The sector
* should have already been allocated prior to the read.
*
****************************************************************************/
static inline int smart_readsector(struct smart_struct_s *dev, unsigned long arg)
{
int ret;
uint32_t readaddr;
uint16_t physsector;
struct smart_read_write_s *req;
struct smart_sect_header_s header;
fvdbg("Entry\n");
req = (struct smart_read_write_s *) arg;
DEBUGASSERT(req->offset < dev->sectorsize);
DEBUGASSERT(req->offset+req->count < dev->sectorsize);
/* Ensure the logical sector has been allocated */
if (req->logsector >= dev->totalsectors)
{
fdbg("Logical sector %d too large\n", req->logsector);
ret = -EINVAL;
goto errout;
}
physsector = dev->sMap[req->logsector];
if (physsector == 0xFFFF)
{
fdbg("Logical sector %d not allocated\n", req->logsector);
ret = -EINVAL;
goto errout;
}
/* Read the sector header data to validate as a sanity check */
ret = MTD_READ(dev->mtd, physsector * dev->mtdBlksPerSector * dev->geo.blocksize,
sizeof(struct smart_sect_header_s), (uint8_t *) &header);
if (ret != sizeof(struct smart_sect_header_s))
{
fvdbg("Error reading sector %d header\n", physsector);
ret = -EIO;
goto errout;
}
/* Do a sanity check on the header data */
if (((*(uint16_t *) header.logicalsector) != req->logsector) ||
((header.status & SMART_STATUS_COMMITTED) ==
(CONFIG_SMARTFS_ERASEDSTATE & SMART_STATUS_COMMITTED)))
{
/* Error in sector header! How do we handle this? */
fdbg("Error in logical sector %d header, phys=%d\n",
req->logsector, physsector);
ret = -EIO;
goto errout;
}
/* Read the sector data into the buffer */
readaddr = (uint32_t) physsector * dev->mtdBlksPerSector * dev->geo.blocksize +
req->offset + sizeof(struct smart_sect_header_s);;
ret = MTD_READ(dev->mtd, readaddr, req->count, (uint8_t *)
req->buffer);
if (ret != req->count)
{
fdbg("Error reading phys sector %d\n", physsector);
ret = -EIO;
goto errout;
}
errout:
return ret;
}
/****************************************************************************
* Name: smart_allocsector
*
* Description: Allocates a new logical sector. If an argument is given,
* then it tries to allocate the specified sector number.
*
****************************************************************************/
#ifdef CONFIG_FS_WRITABLE
static inline int smart_allocsector(struct smart_struct_s *dev, unsigned long requested)
{
int x;
int ret;
uint16_t logsector = 0xFFFF; /* Logical sector number selected */
uint16_t physicalsector; /* The selected physical sector */
uint16_t releasecount;
struct smart_sect_header_s *header;
uint8_t sectsize;
/* Validate that we have enough sectors available to perform an
* allocation. We have to ensure we keep enough reserved sectors
* on hand to do released sector garbage collection. */
releasecount = 0;
for (x = 0; x < dev->neraseblocks; x++)
{
releasecount += dev->releasecount[x];
}
if (dev->freesectors <= (dev->sectorsPerBlk << 0) + 4)
{
/* We are at our free sector limit. Test if we have
* sectors we can release */
if (releasecount == 0)
{
/* No space left!! */
return -ENOSPC;
}
}
/* Check if a specific sector is being requested and allocate that
* sector if it isn't already in use */
if ((requested > 2) && (requested < dev->totalsectors))
{
/* Validate the sector is not already allocated */
if (dev->sMap[requested] == (uint16_t) -1)
{
logsector = requested;
}
}
/* Check if we need to scan for an available logical sector */
if (logsector == 0xFFFF)
{
/* Loop through all sectors and find one to allocate */
for (x = SMART_FIRST_ALLOC_SECTOR; x < dev->totalsectors; x++)
{
if (dev->sMap[x] == (uint16_t) -1)
{
/* Unused logical sector found. Use this one */
logsector = x;
break;
}
}
}
/* Test for an error allocating a sector */
if (logsector == 0xFFFF)
{
/* Hmmm. We think we had enough logical sectors, but
* something happened and we didn't find any free
* logical sectors. What do do? Report an error?
* rescan and try again to "self heal" in case of a
* bug in our code? */
fdbg("No free logical sector numbers! Free sectors = %d\n",
dev->freesectors);
return -EIO;
}
/* Check if we need to do garbage collection. We have to
* ensure we keep enough reserved free sectors to per garbage
* collection as it involves moving sectors from blocks with
* released sectors into blocks with free sectors, then
* erasing the vacated block. */
smart_garbagecollect(dev);
/* Find a free physical sector */
physicalsector = smart_findfreephyssector(dev);
fvdbg("Alloc: log=%d, phys=%d, erase block=%d, free=%d, released=%d\n",
logsector, physicalsector, physicalsector /
dev->sectorsPerBlk, dev->freesectors, releasecount);
/* Create a header to assign the logical sector */
memset(dev->rwbuffer, CONFIG_SMARTFS_ERASEDSTATE, dev->sectorsize);
header = (struct smart_sect_header_s *) dev->rwbuffer;
*((uint16_t *) header->logicalsector) = logsector;
*((uint16_t *) header->seq) = 0;
sectsize = dev->sectorsize >> 7;
#if CONFIG_SMARTFS_ERASEDSTATE == 0xFF
header->status = ~(SMART_STATUS_COMMITTED | SMART_STATUS_SIZEBITS |
SMART_STATUS_VERBITS) | SMART_STATUS_VERSION | sectsize;
#else
header->status = SMART_STATUS_COMMITTED | SMART_STATUS_VERSION | sectsize;
#endif
/* Write the header to the physical sector location */
x = physicalsector * dev->mtdBlksPerSector;
fvdbg("Write MTD block %d\n", x);
ret = MTD_BWRITE(dev->mtd, x, 1, (uint8_t *) dev->rwbuffer);
if (ret != 1)
{
/* The block is not empty!! What to do? */
fdbg("Write block %d failed: %d.\n", x, ret);
/* Unlock the mutex if we add one */
return -EIO;
}
/* Map the sector and update the free sector counts */
dev->sMap[logsector] = physicalsector;
dev->freecount[physicalsector / dev->sectorsPerBlk]--;
dev->freesectors--;
/* Return the logical sector number */
return logsector;
}
#endif /* CONFIG_FS_WRITABLE */
/****************************************************************************
* Name: smart_freesector
*
* Description: Frees a logical sector from the device. Freeing (also
* called releasing) is performed by programming the released
* bit in the sector header's status byte.
*
****************************************************************************/
#ifdef CONFIG_FS_WRITABLE
static inline int smart_freesector(struct smart_struct_s *dev, unsigned long
logicalsector)
{
int ret;
int readaddr;
uint16_t physsector;
uint16_t block;
struct smart_sect_header_s header;
size_t offset;
/* Check if the logical sector is within bounds */
if ((logicalsector > 2) && (logicalsector < dev->totalsectors))
{
/* Validate the sector is actually allocated */
if (dev->sMap[logicalsector] == (uint16_t) -1)
{
fdbg("Invalid release - sector %d not allocated\n", logicalsector);
ret = -EINVAL;
goto errout;
}
}
/* Okay to release the sector. Read the sector header info */
physsector = dev->sMap[logicalsector];
readaddr = physsector * dev->mtdBlksPerSector * dev->geo.blocksize;
ret = MTD_READ(dev->mtd, readaddr, sizeof(struct smart_sect_header_s),
(uint8_t *) &header);
if (ret != sizeof(struct smart_sect_header_s))
{
goto errout;
}
/* Do a sanity check on the logical sector number */
if (*((uint16_t *) header.logicalsector) != (uint16_t) logicalsector)
{
/* Hmmm... something is wrong. This should always match! Bug in our code? */
fdbg("Sector %d logical sector in header doesn't match\n", logicalsector);
ret = -EINVAL;
goto errout;
}
/* Mark the sector as released */
#if CONFIG_SMARTFS_ERASEDSTATE == 0xFF
header.status &= ~SMART_STATUS_RELEASED;
#else
header.status |= SMART_STATUS_RELEASED;
#endif
/* Write the status back to the device */
offset = readaddr + offsetof(struct smart_sect_header_s, status);
ret = smart_bytewrite(dev, offset, 1, &header.status);
if (ret != 1)
{
fdbg("Error updating physicl sector %d status\n", physsector);
goto errout;
}
/* Update the erase block's release count */
block = physsector / dev->sectorsPerBlk;
dev->releasecount[block]++;
/* Unmap this logical sector */
dev->sMap[logicalsector] = (uint16_t) -1;
/* If this block has only released blocks, then erase it */
if (dev->releasecount[block] + dev->freecount[block] == dev->sectorsPerBlk)
{
/* Erase the block */
MTD_ERASE(dev->mtd, block, 1);
dev->freesectors += dev->releasecount[block];
dev->releasecount[block] = 0;
dev->freecount[block] = dev->sectorsPerBlk;
}
ret = OK;
errout:
return ret;
}
#endif /* CONFIG_FS_WRITABLE */
/****************************************************************************
* Name: smart_ioctl
*
* Description: Return device geometry
*
****************************************************************************/
static int smart_ioctl(FAR struct inode *inode, int cmd, unsigned long arg)
{
struct smart_struct_s *dev ;
int ret;
fvdbg("Entry\n");
DEBUGASSERT(inode && inode->i_private);
#ifdef CONFIG_SMARTFS_MULTI_ROOT_DIRS
dev = ((struct smart_multiroot_device_s*) inode->i_private)->dev;
#else
dev = (struct smart_struct_s *)inode->i_private;
#endif
/* Process the ioctl's we care about first, pass any we don't respond
* to directly to the underlying MTD device.
*/
switch (cmd)
{
case BIOC_XIPBASE:
/* The argument accompanying the BIOC_XIPBASE should be non-NULL. If
* DEBUG is enabled, we will catch it here instead of in the MTD
* driver.
*/
#ifdef CONFIG_DEBUG
if (arg == 0)
{
fdbg("ERROR: BIOC_XIPBASE argument is NULL\n");
return -EINVAL;
}
#endif
/* Just change the BIOC_XIPBASE command to the MTDIOC_XIPBASE command. */
cmd = MTDIOC_XIPBASE;
break;
case BIOC_GETFORMAT:
/* Return the format information for the device */
#ifdef CONFIG_SMARTFS_MULTI_ROOT_DIRS
ret = smart_getformat(dev, (struct smart_format_s *) arg,
((struct smart_multiroot_device_s*) inode->i_private)->rootdirnum);
#else
ret = smart_getformat(dev, (struct smart_format_s *) arg);
#endif
goto ok_out;
case BIOC_READSECT:
/* Do a logical sector read and return the data */
ret = smart_readsector(dev, arg);
goto ok_out;
#ifdef CONFIG_FS_WRITABLE
case BIOC_LLFORMAT:
/* Perform a low-level format on the flash */
ret = smart_llformat(dev, arg);
goto ok_out;
case BIOC_ALLOCSECT:
/* Allocate a logical sector for the upper layer file system */
ret = smart_allocsector(dev, arg);
goto ok_out;
case BIOC_FREESECT:
/* Free the specified logical sector */
ret = smart_freesector(dev, arg);
goto ok_out;
case BIOC_WRITESECT:
/* Write to the sector */
ret = smart_writesector(dev, arg);
goto ok_out;
#endif /* CONFIG_FS_WRITABLE */
}
/* No other block driver ioctl commmands are not recognized by this
* driver. Other possible MTD driver ioctl commands are passed through
* to the MTD driver (unchanged).
*/
ret = MTD_IOCTL(dev->mtd, cmd, arg);
if (ret < 0)
{
fdbg("ERROR: MTD ioctl(%04x) failed: %d\n", cmd, ret);
}
ok_out:
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: smart_initialize
*
* Description:
* Initialize to provide a block driver wrapper around an MTD interface
*
* Input Parameters:
* minor - The minor device number. The MTD block device will be
* registered as as /dev/smartN where N is the minor number.
* mtd - The MTD device that supports the FLASH interface.
*
****************************************************************************/
int smart_initialize(int minor, FAR struct mtd_dev_s *mtd, const char *partname)
{
struct smart_struct_s *dev;
int ret = -ENOMEM;
uint32_t totalsectors;
#ifdef CONFIG_SMARTFS_MULTI_ROOT_DIRS
struct smart_multiroot_device_s *rootdirdev;
#endif
/* Sanity check */
#ifdef CONFIG_DEBUG
if (minor < 0 || minor > 255 || !mtd)
{
return -EINVAL;
}
#endif
/* Allocate a SMART device structure */
dev = (struct smart_struct_s *)kmalloc(sizeof(struct smart_struct_s));
if (dev)
{
/* Initialize the SMART device structure */
dev->mtd = mtd;
/* Get the device geometry. (casting to uintptr_t first eliminates
* complaints on some architectures where the sizeof long is different
* from the size of a pointer).
*/
/* Set these to zero in case the device doesn't support them */
ret = MTD_IOCTL(mtd, MTDIOC_GEOMETRY, (unsigned long)((uintptr_t)&dev->geo));
if (ret < 0)
{
fdbg("MTD ioctl(MTDIOC_GEOMETRY) failed: %d\n", ret);
kfree(dev);
goto errout;
}
/* Set the sector size to the default for now */
dev->sMap = NULL;
dev->rwbuffer = NULL;
ret = smart_setsectorsize(dev, CONFIG_MTD_SMART_SECTOR_SIZE);
if (ret != OK)
{
kfree(dev);
goto errout;
}
/* Calculate the totalsectors on this device and validate */
totalsectors = dev->neraseblocks * dev->sectorsPerBlk;
if (totalsectors > 65534)
{
fdbg("SMART Sector size too small for device\n");
kfree(dev);
ret = -EINVAL;
goto errout;
}
dev->freesectors = (uint16_t) totalsectors;
/* Mark the device format status an unknown */
dev->formatstatus = SMART_FMT_STAT_UNKNOWN;
dev->namesize = CONFIG_SMARTFS_MAXNAMLEN;
dev->partname = partname;
#ifdef CONFIG_SMARTFS_MULTI_ROOT_DIRS
dev->minor = minor;
#endif
/* Create a MTD block device name */
#ifdef CONFIG_SMARTFS_MULTI_ROOT_DIRS
if (partname != NULL)
snprintf(dev->rwbuffer, 18, "/dev/smart%d%sd1", minor, partname);
else
snprintf(dev->rwbuffer, 18, "/dev/smart%dd1", minor);
/* Inode private data is a reference to a struct containing
* the SMART device structure and the root directory number.
*/
rootdirdev = (struct smart_multiroot_device_s*) kmalloc(sizeof(*rootdirdev));
if (rootdirdev == NULL)
{
fdbg("register_blockdriver failed: %d\n", -ret);
kfree(dev->sMap);
kfree(dev->rwbuffer);
kfree(dev);
ret = -ENOMEM;
goto errout;
}
/* Populate the rootdirdev */
rootdirdev->dev = dev;
rootdirdev->rootdirnum = 0;
ret = register_blockdriver(dev->rwbuffer, &g_bops, 0, rootdirdev);
#else
if (partname != NULL)
snprintf(dev->rwbuffer, 18, "/dev/smart%d%s", minor, partname);
else
snprintf(dev->rwbuffer, 18, "/dev/smart%d", minor);
/* Inode private data is a reference to the SMART device structure */
ret = register_blockdriver(dev->rwbuffer, &g_bops, 0, dev);
#endif
if (ret < 0)
{
fdbg("register_blockdriver failed: %d\n", -ret);
kfree(dev->sMap);
kfree(dev->rwbuffer);
kfree(dev);
goto errout;
}
/* Do a scan of the device */
smart_scan(dev);
}
errout:
return ret;
}