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Diffstat (limited to 'fs/yaffs2/direct/yaffs_fileem.c')
-rw-r--r--fs/yaffs2/direct/yaffs_fileem.c218
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;
+}
+
+