incubator-nuttx/drivers/mtd/filemtd.c

888 lines
24 KiB
C

/****************************************************************************
* drivers/mtd/filemtd.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mount.h>
#include <stdint.h>
#include <fcntl.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/kmalloc.h>
#include <nuttx/fs/fs.h>
#include <nuttx/fs/ioctl.h>
#include <nuttx/fs/loopmtd.h>
#include <nuttx/mtd/mtd.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
#ifndef CONFIG_FILEMTD_BLOCKSIZE
# define CONFIG_FILEMTD_BLOCKSIZE 512
#endif
#ifndef CONFIG_FILEMTD_ERASESIZE
# define CONFIG_FILEMTD_ERASESIZE 4096
#endif
#ifndef CONFIG_FILEMTD_ERASESTATE
# define CONFIG_FILEMTD_ERASESTATE 0xff
#endif
#if CONFIG_FILEMTD_ERASESTATE != 0xff && CONFIG_FILEMTD_ERASESTATE != 0x00
# error "Unsupported value for CONFIG_FILEMTD_ERASESTATE"
#endif
#if CONFIG_FILEMTD_BLOCKSIZE > CONFIG_FILEMTD_ERASESIZE
# error "Must have CONFIG_FILEMTD_BLOCKSIZE <= CONFIG_FILEMTD_ERASESIZE"
#endif
#undef FILEMTD_BLKPER
#define FILEMTD_BLKPER (CONFIG_FILEMTD_ERASESIZE/CONFIG_FILEMTD_BLOCKSIZE)
#if FILEMTD_BLKPER*CONFIG_FILEMTD_BLOCKSIZE != CONFIG_FILEMTD_ERASESIZE
# error "CONFIG_FILEMTD_ERASESIZE must be an even multiple of CONFIG_FILEMTD_BLOCKSIZE"
#endif
/****************************************************************************
* Private Types
****************************************************************************/
/* This type represents the state of the MTD device. The struct mtd_dev_s
* must appear at the beginning of the definition so that you can freely
* cast between pointers to struct mtd_dev_s and struct file_dev_s.
*/
struct file_dev_s
{
struct mtd_dev_s mtd; /* MTD device */
struct file mtdfile;
size_t nblocks; /* Number of erase blocks */
size_t offset; /* Offset from start of file */
size_t erasesize; /* Offset from start of file */
size_t blocksize; /* Offset from start of file */
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static ssize_t filemtd_read(FAR struct file_dev_s *priv,
FAR unsigned char *buffer, size_t offsetbytes,
unsigned int nbytes);
static ssize_t filemtd_write(FAR struct file_dev_s *priv, size_t offset,
FAR const void *src, size_t len);
/* MTD driver methods */
static int filemtd_erase(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks);
static ssize_t filemtd_bread(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks, FAR uint8_t *buf);
static ssize_t filemtd_bwrite(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks, FAR const uint8_t *buf);
static ssize_t filemtd_byteread(FAR struct mtd_dev_s *dev, off_t offset,
size_t nbytes, FAR uint8_t *buf);
#ifdef CONFIG_MTD_BYTE_WRITE
static ssize_t file_bytewrite(FAR struct mtd_dev_s *dev, off_t offset,
size_t nbytes, FAR const uint8_t *buf);
#endif
static int filemtd_ioctl(FAR struct mtd_dev_s *dev, int cmd,
unsigned long arg);
#ifdef CONFIG_MTD_LOOP
static ssize_t mtd_loop_read(FAR struct file *filep, FAR char *buffer,
size_t buflen);
static ssize_t mtd_loop_write(FAR struct file *filep,
FAR const char *buffer, size_t buflen);
static int mtd_loop_ioctl(FAR struct file *filep, int cmd,
unsigned long arg);
#endif /* CONFIG_MTD_LOOP */
/****************************************************************************
* Private Data
****************************************************************************/
#ifdef CONFIG_MTD_LOOP
static const struct file_operations g_fops =
{
NULL, /* open */
NULL, /* close */
mtd_loop_read, /* read */
mtd_loop_write, /* write */
NULL, /* seek */
mtd_loop_ioctl, /* ioctl */
};
#endif /* CONFIG_MTD_LOOP */
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: filemtd_write
****************************************************************************/
static ssize_t filemtd_write(FAR struct file_dev_s *priv, size_t offset,
FAR const void *src, size_t len)
{
FAR const uint8_t *pin = (FAR const uint8_t *)src;
FAR uint8_t *pout = NULL;
char buf[128];
int buflen;
int remain = 0;
uint8_t oldvalue;
uint8_t srcvalue;
uint8_t newvalue;
size_t seekpos;
/* Set the starting location in the file */
seekpos = priv->offset + offset;
for (buflen = 0; len > 0; len--)
{
if (buflen == 0)
{
/* Read more data from the file */
file_seek(&priv->mtdfile, seekpos, SEEK_SET);
buflen = file_read(&priv->mtdfile, buf, MIN(len, sizeof(buf)));
pout = (FAR uint8_t *)buf;
remain = buflen;
}
/* Get the source and destination values */
oldvalue = *pout;
srcvalue = *pin++;
/* Get the new destination value, accounting for bits that cannot be
* changes because they are not in the erased state.
*/
#if CONFIG_FILEMTD_ERASESTATE == 0xff
newvalue = oldvalue & srcvalue; /* We can only clear bits */
#else /* CONFIG_FILEMTD_ERASESTATE == 0x00 */
newvalue = oldvalue | srcvalue; /* We can only set bits */
#endif
/* Report any attempt to change the value of bits that are not in the
* erased state.
*/
#ifdef CONFIG_DEBUG_FEATURES
if (newvalue != srcvalue)
{
ferr("ERROR: Bad write: source=%02x dest=%02x result=%02x\n",
srcvalue, oldvalue, newvalue);
}
#endif
/* Write the modified value to simulated FLASH */
*pout++ = newvalue;
remain--;
/* If our buffer is full, then seek back to beginning of
* the file and write the buffer contents
*/
if (remain == 0)
{
file_seek(&priv->mtdfile, seekpos, SEEK_SET);
file_write(&priv->mtdfile, buf, buflen);
seekpos += buflen;
buflen = 0;
}
}
/* Write remaining bytes */
if (buflen != 0)
{
file_seek(&priv->mtdfile, seekpos, SEEK_SET);
file_write(&priv->mtdfile, buf, buflen);
}
return len;
}
/****************************************************************************
* Name: filemtd_read
****************************************************************************/
static ssize_t filemtd_read(FAR struct file_dev_s *priv,
FAR unsigned char *buffer, size_t offsetbytes,
unsigned int nbytes)
{
/* Set the starting location in the file */
file_seek(&priv->mtdfile, priv->offset + offsetbytes, SEEK_SET);
return file_read(&priv->mtdfile, buffer, nbytes);
}
/****************************************************************************
* Name: filemtd_erase
****************************************************************************/
static int filemtd_erase(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks)
{
FAR struct file_dev_s *priv = (FAR struct file_dev_s *)dev;
size_t nbytes;
size_t offset;
char buffer[128];
DEBUGASSERT(dev);
/* Don't let the erase exceed the original size of the file */
if (startblock >= priv->nblocks)
{
return 0;
}
if (startblock + nblocks > priv->nblocks)
{
nblocks = priv->nblocks - startblock;
}
/* Convert the erase block to a logical block and the number of blocks
* in logical block numbers
*/
startblock *= (priv->erasesize / priv->blocksize);
nblocks *= (priv->erasesize / priv->blocksize);
/* Get the offset corresponding to the first block and the size
* corresponding to the number of blocks.
*/
offset = startblock * priv->blocksize;
nbytes = nblocks * priv->blocksize;
/* Then erase the data in the file */
file_seek(&priv->mtdfile, priv->offset + offset, SEEK_SET);
memset(buffer, CONFIG_FILEMTD_ERASESTATE, sizeof(buffer));
while (nbytes > 0)
{
file_write(&priv->mtdfile, buffer, MIN(nbytes, sizeof(buffer)));
nbytes -= MIN(nbytes, sizeof(buffer));
}
return OK;
}
/****************************************************************************
* Name: filemtd_bread
****************************************************************************/
static ssize_t filemtd_bread(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks, FAR uint8_t *buf)
{
FAR struct file_dev_s *priv = (FAR struct file_dev_s *)dev;
off_t offset;
off_t maxblock;
size_t nbytes;
DEBUGASSERT(dev && buf);
/* Don't let the read exceed the original size of the file */
maxblock = priv->nblocks * (priv->erasesize / priv->blocksize);
if (startblock >= maxblock)
{
return 0;
}
if (startblock + nblocks > maxblock)
{
nblocks = maxblock - startblock;
}
/* Get the offset corresponding to the first block and the size
* corresponding to the number of blocks.
*/
offset = startblock * priv->blocksize;
nbytes = nblocks * priv->blocksize;
/* Then read the data from the file */
filemtd_read(priv, buf, offset, nbytes);
return nblocks;
}
/****************************************************************************
* Name: filemtd_bwrite
****************************************************************************/
static ssize_t filemtd_bwrite(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks, FAR const uint8_t *buf)
{
FAR struct file_dev_s *priv = (FAR struct file_dev_s *)dev;
off_t offset;
off_t maxblock;
size_t nbytes;
DEBUGASSERT(dev && buf);
/* Don't let the write exceed the original size of the file */
maxblock = priv->nblocks * (priv->erasesize / priv->blocksize);
if (startblock >= maxblock)
{
return 0;
}
if (startblock + nblocks > maxblock)
{
nblocks = maxblock - startblock;
}
/* Get the offset corresponding to the first block and the size
* corresponding to the number of blocks.
*/
offset = startblock * priv->blocksize;
nbytes = nblocks * priv->blocksize;
/* Then write the data to the file */
filemtd_write(priv, offset, buf, nbytes);
return nblocks;
}
/****************************************************************************
* Name: filemtd_byteread
****************************************************************************/
static ssize_t filemtd_byteread(FAR struct mtd_dev_s *dev, off_t offset,
size_t nbytes, FAR uint8_t *buf)
{
FAR struct file_dev_s *priv = (FAR struct file_dev_s *)dev;
off_t maxoffset;
DEBUGASSERT(dev && buf);
/* Don't let the read exceed the original size of the file */
maxoffset = priv->nblocks * priv->erasesize;
if (offset >= maxoffset)
{
return 0;
}
if (offset + nbytes > maxoffset)
{
nbytes = maxoffset - offset;
}
filemtd_read(priv, buf, offset, nbytes);
return nbytes;
}
/****************************************************************************
* Name: file_bytewrite
****************************************************************************/
#ifdef CONFIG_MTD_BYTE_WRITE
static ssize_t file_bytewrite(FAR struct mtd_dev_s *dev, off_t offset,
size_t nbytes, FAR const uint8_t *buf)
{
FAR struct file_dev_s *priv = (FAR struct file_dev_s *)dev;
off_t maxoffset;
DEBUGASSERT(dev && buf);
/* Don't let the write exceed the original size of the file */
maxoffset = priv->nblocks * priv->erasesize;
if (offset + nbytes > maxoffset)
{
return 0;
}
if (offset + nbytes > maxoffset)
{
nbytes = maxoffset - offset;
}
/* Then write the data to the file */
filemtd_write(priv, offset, buf, nbytes);
return nbytes;
}
#endif
/****************************************************************************
* Name: filemtd_ioctl
****************************************************************************/
static int filemtd_ioctl(FAR struct mtd_dev_s *dev, int cmd,
unsigned long arg)
{
FAR struct file_dev_s *priv = (FAR struct file_dev_s *)dev;
int ret = -EINVAL; /* Assume good command with bad parameters */
switch (cmd)
{
case MTDIOC_GEOMETRY:
{
FAR struct mtd_geometry_s *geo =
(FAR struct mtd_geometry_s *)((uintptr_t)arg);
if (geo)
{
memset(geo, 0, sizeof(*geo));
/* Populate the geometry structure with information need to
* know the capacity and how to access the device.
*/
geo->blocksize = priv->blocksize;
geo->erasesize = priv->erasesize;
geo->neraseblocks = priv->nblocks;
ret = OK;
}
}
break;
case BIOC_PARTINFO:
{
FAR struct partition_info_s *info =
(FAR struct partition_info_s *)arg;
if (info != NULL)
{
info->numsectors = priv->nblocks *
priv->erasesize / priv->blocksize;
info->sectorsize = priv->blocksize;
info->startsector = 0;
info->parent[0] = '\0';
ret = OK;
}
}
break;
case MTDIOC_BULKERASE:
{
/* Erase the entire device */
ret = filemtd_erase(dev, 0, priv->nblocks);
}
break;
case MTDIOC_ERASESTATE:
{
FAR uint8_t *result = (FAR uint8_t *)arg;
*result = CONFIG_FILEMTD_ERASESTATE;
ret = OK;
}
break;
default:
ret = -ENOTTY; /* Bad command */
break;
}
return ret;
}
/****************************************************************************
* Name: mtd_loop_setup
*
* Description: Dynamically setups up a FILEMTD enabled loop device that
* is backed by a file. The resulting loop device is a
* MTD type block device vs. a generic block device.
*
****************************************************************************/
#ifdef CONFIG_MTD_LOOP
static int mtd_loop_setup(FAR const char *devname, FAR const char *filename,
int sectsize, int erasesize, off_t offset)
{
FAR struct mtd_dev_s *mtd;
int ret;
mtd = filemtd_initialize(filename, offset, sectsize, erasesize);
if (mtd == NULL)
{
return -ENOENT;
}
ret = register_mtddriver(devname, mtd, 0755, NULL);
if (ret != OK)
{
filemtd_teardown(mtd);
}
return ret;
}
#endif /* CONFIG_MTD_LOOP */
/****************************************************************************
* Name: mtd_loop_teardown
*
* Description:
* Undo the setup performed by loopmtd_setup
*
****************************************************************************/
#ifdef CONFIG_MTD_LOOP
static int mtd_loop_teardown(FAR const char *devname)
{
FAR struct file_dev_s *dev;
FAR struct inode *inode;
int ret;
/* Open the block driver associated with devname so that we can get the
* inode reference.
*/
ret = open_blockdriver(devname, MS_RDONLY, &inode);
if (ret < 0)
{
ferr("ERROR: Failed to open %s: %d\n", devname, -ret);
return ret;
}
/* Inode private data is a reference to the loop device structure */
dev = (FAR struct file_dev_s *)inode->u.i_mtd;
/* Validate this is a filemtd backended device */
if (!filemtd_isfilemtd(&dev->mtd))
{
ferr("ERROR: Device is not a FILEMTD loop: %s\n", devname);
return -EINVAL;
}
close_blockdriver(inode);
/* Now teardown the filemtd */
filemtd_teardown(&dev->mtd);
unregister_blockdriver(devname);
kmm_free(dev);
return OK;
}
#endif /* CONFIG_MTD_LOOP */
/****************************************************************************
* Name: mtd_loop_read
****************************************************************************/
#ifdef CONFIG_MTD_LOOP
static ssize_t mtd_loop_read(FAR struct file *filep, FAR char *buffer,
size_t len)
{
return 0; /* Return EOF */
}
#endif /* CONFIG_MTD_LOOP */
/****************************************************************************
* Name: mtd_loop_write
****************************************************************************/
#ifdef CONFIG_MTD_LOOP
static ssize_t mtd_loop_write(FAR struct file *filep,
FAR const char *buffer, size_t len)
{
return len; /* Say that everything was written */
}
#endif /* CONFIG_MTD_LOOP */
/****************************************************************************
* Name: mtd_loop_ioctl
****************************************************************************/
#ifdef CONFIG_MTD_LOOP
static int mtd_loop_ioctl(FAR struct file *filep, int cmd,
unsigned long arg)
{
int ret;
switch (cmd)
{
/* Command: LOOPIOC_SETUP
* Description: Setup the loop device
* Argument: A pointer to a read-only instance of struct losetup_s.
* Dependencies: The loop device must be enabled (CONFIG_MTD_LOOP=y)
*/
case MTD_LOOPIOC_SETUP:
{
FAR struct mtd_losetup_s *setup =
(FAR struct mtd_losetup_s *)((uintptr_t)arg);
if (setup == NULL)
{
ret = -EINVAL;
}
else
{
ret = mtd_loop_setup(setup->devname, setup->filename,
setup->sectsize, setup->erasesize,
setup->offset);
}
}
break;
/* Command: LOOPIOC_TEARDOWN
* Description: Teardown a loop device previously setup via
* LOOPIOC_SETUP
* Argument: A read-able pointer to the path of the device to be
* torn down
* Dependencies: The loop device must be enabled (CONFIG_MTD_LOOP=y)
*/
case MTD_LOOPIOC_TEARDOWN:
{
FAR const char *devname = (FAR const char *)((uintptr_t)arg);
if (devname == NULL)
{
ret = -EINVAL;
}
else
{
ret = mtd_loop_teardown(devname);
}
}
break;
default:
ret = -ENOTTY;
}
return ret;
}
#endif /* CONFIG_MTD_LOOP */
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: filemtd_initialize
*
* Description:
* Create and initialize a FILE MTD device instance.
*
* Input Parameters:
* path - Path name of the file backing the MTD device
*
****************************************************************************/
FAR struct mtd_dev_s *filemtd_initialize(FAR const char *path, size_t offset,
int16_t sectsize, int32_t erasesize)
{
FAR struct file_dev_s *priv;
struct stat sb;
size_t nblocks;
size_t filelen;
int mode;
int ret;
/* Stat the file */
ret = nx_stat(path, &sb, 1);
if (ret < 0)
{
ferr("ERROR: Failed to stat %s: %d\n", path, ret);
return NULL;
}
filelen = sb.st_size;
if (offset > filelen)
{
ferr("ERROR: Offset beyond end of file\n");
return NULL;
}
filelen = filelen - offset;
/* Create an instance of the FILE MTD device state structure */
priv = (FAR struct file_dev_s *)kmm_zalloc(sizeof(struct file_dev_s));
if (!priv)
{
ferr("ERROR: Failed to allocate the FILE MTD state structure\n");
return NULL;
}
/* Set the file open mode. */
mode = O_RDOK | O_WROK;
/* Try to open the file. NOTE that block devices will use a character
* driver proxy.
*/
ret = file_open(&priv->mtdfile, path, mode);
if (ret < 0)
{
ferr("ERROR: Failed to open the FILE MTD file %s: %d\n", path, ret);
kmm_free(priv);
return NULL;
}
/* Set the block size based on the provided sectsize parameter */
if (sectsize <= 0)
{
priv->blocksize = CONFIG_FILEMTD_BLOCKSIZE;
}
else
{
priv->blocksize = sectsize;
}
/* Set the erase size based on the provided erasesize parameter */
if (erasesize <= 0)
{
priv->erasesize = CONFIG_FILEMTD_ERASESIZE;
}
else
{
priv->erasesize = erasesize;
}
if ((priv->erasesize / priv->blocksize) * priv->blocksize
!= priv->erasesize)
{
ferr("ERROR: erasesize must be an even multiple of sectsize\n");
file_close(&priv->mtdfile);
kmm_free(priv);
return NULL;
}
/* Force the size to be an even number of the erase block size */
nblocks = filelen / priv->erasesize;
if (nblocks < 3)
{
ferr("ERROR: Need to provide at least three full erase block\n");
file_close(&priv->mtdfile);
kmm_free(priv);
return NULL;
}
/* Perform initialization as necessary. (unsupported methods were
* nullified by kmm_zalloc).
*/
priv->mtd.erase = filemtd_erase;
priv->mtd.bread = filemtd_bread;
priv->mtd.bwrite = filemtd_bwrite;
priv->mtd.read = filemtd_byteread;
#ifdef CONFIG_MTD_BYTE_WRITE
priv->mtd.write = file_bytewrite;
#endif
priv->mtd.ioctl = filemtd_ioctl;
priv->mtd.name = "filemtd";
priv->offset = offset;
priv->nblocks = nblocks;
return &priv->mtd;
}
/****************************************************************************
* Name: filemtd_teardown
*
* Description:
* Teardown a previously created filemtd device.
*
* Input Parameters:
* dev - Pointer to the mtd driver instance.
*
****************************************************************************/
void filemtd_teardown(FAR struct mtd_dev_s *dev)
{
FAR struct file_dev_s *priv = (FAR struct file_dev_s *)dev;
/* Close the enclosed file */
file_close(&priv->mtdfile);
#ifdef CONFIG_MTD_REGISTRATION
/* Un-register the MTD with the procfs system if enabled */
mtd_unregister(&priv->mtd);
#endif
/* Free the memory */
kmm_free(priv);
}
/****************************************************************************
* Name: filemtd_isfilemtd
*
* Description:
* Tests if the provided mtd is a filemtd device.
*
* Input Parameters:
* mtd - Pointer to the mtd.
*
****************************************************************************/
bool filemtd_isfilemtd(FAR struct mtd_dev_s *dev)
{
FAR struct file_dev_s *priv = (FAR struct file_dev_s *)dev;
return (priv->mtd.erase == filemtd_erase);
}
/****************************************************************************
* Name: mtd_loop_register_driver
*
* Description:
* Registers MTD Loop Driver
****************************************************************************/
#ifdef CONFIG_MTD_LOOP
int mtd_loop_register(void)
{
return register_driver("/dev/loopmtd", &g_fops, 0666, NULL);
}
#endif