diff options
Diffstat (limited to 'fs/yaffs2/direct/yaffs_fileem.c')
| -rw-r--r-- | fs/yaffs2/direct/yaffs_fileem.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/fs/yaffs2/direct/yaffs_fileem.c b/fs/yaffs2/direct/yaffs_fileem.c new file mode 100644 index 0000000..e3cc30e --- /dev/null +++ b/fs/yaffs2/direct/yaffs_fileem.c @@ -0,0 +1,218 @@ +/* + * YAFFS: Yet Another Flash File System. A NAND-flash specific file system. + * + * Copyright (C) 2002-2007 Aleph One Ltd. + * for Toby Churchill Ltd and Brightstar Engineering + * + * Created by Charles Manning <charles@aleph1.co.uk> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +/* + * This provides a YAFFS nand emulation on a file. + * This is only intended as test code to test persistence etc. + */ + +const char *yaffs_flashif_c_version = "$Id: yaffs_fileem.c,v 1.3 2007/02/14 01:09:06 wookey Exp $"; + + +#include "yportenv.h" + +#include "yaffs_flashif.h" +#include "yaffs_guts.h" + +#include "devextras.h" + +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <unistd.h> + + + +#define SIZE_IN_MB 16 + +#define BLOCK_SIZE (32 * 528) +#define BLOCKS_PER_MEG ((1024*1024)/(32 * 512)) + + + +typedef struct +{ + __u8 data[528]; // Data + spare +} yflash_Page; + +typedef struct +{ + yflash_Page page[32]; // The pages in the block + +} yflash_Block; + + + +typedef struct +{ + int handle; + int nBlocks; +} yflash_Device; + +static yflash_Device filedisk; + +static int CheckInit(yaffs_Device *dev) +{ + static int initialised = 0; + + int i; + + + int fSize; + int written; + + yflash_Page p; + + if(initialised) + { + return YAFFS_OK; + } + + initialised = 1; + + + filedisk.nBlocks = (SIZE_IN_MB * 1024 * 1024)/(16 * 1024); + + filedisk.handle = open("yaffsemfile", O_RDWR | O_CREAT, S_IREAD | S_IWRITE); + + if(filedisk.handle < 0) + { + perror("Failed to open yaffs emulation file"); + return YAFFS_FAIL; + } + + + fSize = lseek(filedisk.handle,0,SEEK_END); + + if(fSize < SIZE_IN_MB * 1024 * 1024) + { + printf("Creating yaffs emulation file\n"); + + lseek(filedisk.handle,0,SEEK_SET); + + memset(&p,0xff,sizeof(yflash_Page)); + + for(i = 0; i < SIZE_IN_MB * 1024 * 1024; i+= 512) + { + written = write(filedisk.handle,&p,sizeof(yflash_Page)); + + if(written != sizeof(yflash_Page)) + { + printf("Write failed\n"); + return YAFFS_FAIL; + } + } + } + + return 1; +} + +int yflash_WriteChunkToNAND(yaffs_Device *dev,int chunkInNAND,const __u8 *data, const yaffs_Spare *spare) +{ + int written; + + CheckInit(dev); + + + + if(data) + { + lseek(filedisk.handle,chunkInNAND * 528,SEEK_SET); + written = write(filedisk.handle,data,512); + + if(written != 512) return YAFFS_FAIL; + } + + if(spare) + { + lseek(filedisk.handle,chunkInNAND * 528 + 512,SEEK_SET); + written = write(filedisk.handle,spare,16); + + if(written != 16) return YAFFS_FAIL; + } + + + return YAFFS_OK; + +} + + +int yflash_ReadChunkFromNAND(yaffs_Device *dev,int chunkInNAND, __u8 *data, yaffs_Spare *spare) +{ + int nread; + + CheckInit(dev); + + + + if(data) + { + lseek(filedisk.handle,chunkInNAND * 528,SEEK_SET); + nread = read(filedisk.handle,data,512); + + if(nread != 512) return YAFFS_FAIL; + } + + if(spare) + { + lseek(filedisk.handle,chunkInNAND * 528 + 512,SEEK_SET); + nread= read(filedisk.handle,spare,16); + + if(nread != 16) return YAFFS_FAIL; + } + + + return YAFFS_OK; + +} + + +int yflash_EraseBlockInNAND(yaffs_Device *dev, int blockNumber) +{ + + int i; + + CheckInit(dev); + + if(blockNumber < 0 || blockNumber >= filedisk.nBlocks) + { + T(YAFFS_TRACE_ALWAYS,("Attempt to erase non-existant block %d\n",blockNumber)); + return YAFFS_FAIL; + } + else + { + + yflash_Page pg; + + memset(&pg,0xff,sizeof(yflash_Page)); + + lseek(filedisk.handle, blockNumber * 32 * 528, SEEK_SET); + + for(i = 0; i < 32; i++) + { + write(filedisk.handle,&pg,528); + } + return YAFFS_OK; + } + +} + +int yflash_InitialiseNAND(yaffs_Device *dev) +{ + dev->useNANDECC = 1; // force on useNANDECC which gets faked. + // This saves us doing ECC checks. + + return YAFFS_OK; +} + + |