mirror of
https://gitee.com/mirrors_PX4/PX4-Autopilot.git
synced 2026-10-30 09:23:33 +08:00
Resync new repository with old repo r5166
git-svn-id: http://svn.code.sf.net/p/nuttx/code/trunk@5153 42af7a65-404d-4744-a932-0658087f49c3
This commit is contained in:
patacongo
@@ -0,0 +1,261 @@
|
||||
/****************************************************************************
|
||||
* fs/nxffs/nxffs_cache.c
|
||||
*
|
||||
* Copyright (C) 2011 Gregory Nutt. All rights reserved.
|
||||
* Author: Gregory Nutt <gnutt@nuttx.org>
|
||||
*
|
||||
* References: Linux/Documentation/filesystems/romfs.txt
|
||||
*
|
||||
* 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 <assert.h>
|
||||
#include <errno.h>
|
||||
#include <debug.h>
|
||||
|
||||
#include <nuttx/mtd.h>
|
||||
|
||||
#include "nxffs.h"
|
||||
|
||||
/****************************************************************************
|
||||
* Pre-processor Definitions
|
||||
****************************************************************************/
|
||||
|
||||
/****************************************************************************
|
||||
* Public Types
|
||||
****************************************************************************/
|
||||
|
||||
/****************************************************************************
|
||||
* Public Variables
|
||||
****************************************************************************/
|
||||
|
||||
/****************************************************************************
|
||||
* Private Functions
|
||||
****************************************************************************/
|
||||
|
||||
/****************************************************************************
|
||||
* Public Functions
|
||||
****************************************************************************/
|
||||
|
||||
/****************************************************************************
|
||||
* Name: nxffs_rdcache
|
||||
*
|
||||
* Description:
|
||||
* Read one I/O block into the volume block cache memory.
|
||||
*
|
||||
* Input Parameters:
|
||||
* volume - Describes the current volume
|
||||
* block - The first logical block to read
|
||||
*
|
||||
* Returned Value:
|
||||
* Negated errnos are returned only in the case of MTD reported failures.
|
||||
* Nothing in the volume data itself will generate errors.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
int nxffs_rdcache(FAR struct nxffs_volume_s *volume, off_t block)
|
||||
{
|
||||
size_t nxfrd;
|
||||
|
||||
/* Check if the requested data is already in the cache */
|
||||
|
||||
if (block != volume->cblock)
|
||||
{
|
||||
/* Read the specified blocks into cache */
|
||||
|
||||
nxfrd = MTD_BREAD(volume->mtd, block, 1, volume->cache);
|
||||
if (nxfrd != 1)
|
||||
{
|
||||
fvdbg("Read block %d failed: %d\n", block, nxfrd);
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
/* Remember what is in the cache */
|
||||
|
||||
volume->cblock = block;
|
||||
}
|
||||
return OK;
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Name: nxffs_wrcache
|
||||
*
|
||||
* Description:
|
||||
* Write one or more logical blocks from the volume cache memory.
|
||||
*
|
||||
* Input Parameters:
|
||||
* volume - Describes the current volume
|
||||
*
|
||||
* Returned Value:
|
||||
* Negated errnos are returned only in the case of MTD reported failures.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
int nxffs_wrcache(FAR struct nxffs_volume_s *volume)
|
||||
{
|
||||
size_t nxfrd;
|
||||
|
||||
/* Write the current block from the cache */
|
||||
|
||||
nxfrd = MTD_BWRITE(volume->mtd, volume->cblock, 1, volume->cache);
|
||||
if (nxfrd != 1)
|
||||
{
|
||||
fdbg("Write block %d failed: %d\n", volume->cblock, nxfrd);
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
/* Write was successful */
|
||||
|
||||
return OK;
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Name: nxffs_ioseek
|
||||
*
|
||||
* Description:
|
||||
* Seek to a position in FLASH memory. This simply sets up the offsets
|
||||
* and pointer values. This is a necessary step prior to using
|
||||
* nxffs_getc().
|
||||
*
|
||||
* Input Parameters:
|
||||
* volume - Describes the NXFFS volume
|
||||
* offset - The physical offset in bytes from the beginning of the FLASH
|
||||
* in bytes.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
void nxffs_ioseek(FAR struct nxffs_volume_s *volume, off_t offset)
|
||||
{
|
||||
/* Convert the offset into a block number and a byte offset into the
|
||||
* block.
|
||||
*/
|
||||
|
||||
volume->ioblock = offset / volume->geo.blocksize;
|
||||
volume->iooffset = offset - volume->geo.blocksize * volume->ioblock;
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Name: nxffs_iotell
|
||||
*
|
||||
* Description:
|
||||
* Report the current position.
|
||||
*
|
||||
* Input Parameters:
|
||||
* volume - Describes the NXFFS volume
|
||||
*
|
||||
* Returned Value:
|
||||
* The offset from the beginning of FLASH to the current seek position.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
off_t nxffs_iotell(FAR struct nxffs_volume_s *volume)
|
||||
{
|
||||
return volume->ioblock * volume->geo.blocksize + volume->iooffset;
|
||||
}
|
||||
|
||||
/****************************************************************************
|
||||
* Name: nxffs_getc
|
||||
*
|
||||
* Description:
|
||||
* Get the next byte from FLASH. This function allows the data in the
|
||||
* formatted FLASH blocks to be read as a continuous byte stream, skipping
|
||||
* over bad blocks and block headers as necessary.
|
||||
*
|
||||
* Input Parameters:
|
||||
* volume - Describes the NXFFS volume. The paramters ioblock and iooffset
|
||||
* in the volume structure determine the behavior of nxffs_getc().
|
||||
* reserve - If less than this much space is available at the end of the
|
||||
* block, then skip to the next block.
|
||||
*
|
||||
* Returned Value:
|
||||
* Zero is returned on success. Otherwise, a negated errno indicating the
|
||||
* nature of the failure.
|
||||
*
|
||||
****************************************************************************/
|
||||
|
||||
int nxffs_getc(FAR struct nxffs_volume_s *volume, uint16_t reserve)
|
||||
{
|
||||
int ret;
|
||||
|
||||
DEBUGASSERT(reserve > 0);
|
||||
|
||||
/* Loop to skip over bad blocks */
|
||||
|
||||
do
|
||||
{
|
||||
/* Check if we have the reserve amount at the end of the current block */
|
||||
|
||||
if (volume->iooffset + reserve > volume->geo.blocksize)
|
||||
{
|
||||
/* Check for attempt to read past the end of FLASH */
|
||||
|
||||
off_t nextblock = volume->ioblock + 1;
|
||||
if (nextblock >= volume->nblocks)
|
||||
{
|
||||
fvdbg("End of FLASH encountered\n");
|
||||
return -ENOSPC;
|
||||
}
|
||||
|
||||
/* Set up the seek to the data just after the header in the
|
||||
* next block.
|
||||
*/
|
||||
|
||||
volume->ioblock = nextblock;
|
||||
volume->iooffset = SIZEOF_NXFFS_BLOCK_HDR;
|
||||
}
|
||||
|
||||
/* Make sure that the block is in the cache. The special error
|
||||
* -ENOENT indicates the block was read successfully but was not
|
||||
* marked as a good block. In this case we need to skip to the
|
||||
* next block. All other errors are fatal.
|
||||
*/
|
||||
|
||||
ret = nxffs_verifyblock(volume, volume->ioblock);
|
||||
if (ret < 0 && ret != -ENOENT)
|
||||
{
|
||||
fvdbg("Failed to read valid data into cache: %d\n", ret);
|
||||
return ret;
|
||||
}
|
||||
}
|
||||
while (ret != OK);
|
||||
|
||||
/* Return the the character at this offset. Note that on return,
|
||||
* iooffset could point to the byte outside of the current block.
|
||||
*/
|
||||
|
||||
ret = (int)volume->cache[volume->iooffset];
|
||||
volume->iooffset++;
|
||||
return ret;
|
||||
}
|
||||
Reference in New Issue
Block a user