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-rw-r--r--fs/yaffs2/direct/yaffs_ramem2k.c363
1 files changed, 363 insertions, 0 deletions
diff --git a/fs/yaffs2/direct/yaffs_ramem2k.c b/fs/yaffs2/direct/yaffs_ramem2k.c
new file mode 100644
index 0000000000..1ab053c467
--- /dev/null
+++ b/fs/yaffs2/direct/yaffs_ramem2k.c
@@ -0,0 +1,363 @@
+/*
+ * 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.
+ */
+
+/*
+ * yaffs_ramem2k.c: RAM emulation in-kernel for 2K pages (YAFFS2)
+ */
+
+
+const char *yaffs_ramem2k_c_version = "$Id: yaffs_ramem2k.c,v 1.3 2007/02/14 01:09:06 wookey Exp $";
+
+#ifndef __KERNEL__
+#define CONFIG_YAFFS_RAM_ENABLED
+#else
+#include <linux/config.h>
+#endif
+
+#ifdef CONFIG_YAFFS_RAM_ENABLED
+
+#include "yportenv.h"
+
+#include "yaffs_nandemul2k.h"
+#include "yaffs_guts.h"
+#include "yaffsinterface.h"
+#include "devextras.h"
+#include "yaffs_packedtags2.h"
+
+
+
+#define EM_SIZE_IN_MEG (32)
+#define PAGE_DATA_SIZE (2048)
+#define PAGE_SPARE_SIZE (64)
+#define PAGES_PER_BLOCK (64)
+
+
+
+#define EM_SIZE_IN_BYTES (EM_SIZE_IN_MEG * (1<<20))
+
+#define PAGE_TOTAL_SIZE (PAGE_DATA_SIZE+PAGE_SPARE_SIZE)
+
+#define BLOCK_TOTAL_SIZE (PAGES_PER_BLOCK * PAGE_TOTAL_SIZE)
+
+#define BLOCKS_PER_MEG ((1<<20)/(PAGES_PER_BLOCK * PAGE_DATA_SIZE))
+
+
+typedef struct
+{
+ __u8 data[PAGE_TOTAL_SIZE]; // Data + spare
+ int empty; // is this empty?
+} nandemul_Page;
+
+
+typedef struct
+{
+ nandemul_Page *page[PAGES_PER_BLOCK];
+ int damaged;
+} nandemul_Block;
+
+
+
+typedef struct
+{
+ nandemul_Block**block;
+ int nBlocks;
+} nandemul_Device;
+
+static nandemul_Device ned;
+
+static int sizeInMB = EM_SIZE_IN_MEG;
+
+
+static void nandemul_yield(int n)
+{
+#ifdef __KERNEL__
+ if(n > 0) schedule_timeout(n);
+#endif
+
+}
+
+
+static void nandemul_ReallyEraseBlock(int blockNumber)
+{
+ int i;
+
+ nandemul_Block *blk;
+
+ if(blockNumber < 0 || blockNumber >= ned.nBlocks)
+ {
+ return;
+ }
+
+ blk = ned.block[blockNumber];
+
+ for(i = 0; i < PAGES_PER_BLOCK; i++)
+ {
+ memset(blk->page[i],0xff,sizeof(nandemul_Page));
+ blk->page[i]->empty = 1;
+ }
+ nandemul_yield(2);
+}
+
+
+static int nandemul2k_CalcNBlocks(void)
+{
+ return EM_SIZE_IN_MEG * BLOCKS_PER_MEG;
+}
+
+
+
+static int CheckInit(void)
+{
+ static int initialised = 0;
+
+ int i,j;
+
+ int fail = 0;
+ int nBlocks;
+
+ int nAllocated = 0;
+
+ if(initialised)
+ {
+ return YAFFS_OK;
+ }
+
+
+ ned.nBlocks = nBlocks = nandemul2k_CalcNBlocks();
+
+
+ ned.block = YMALLOC(sizeof(nandemul_Block*) * nBlocks );
+
+ if(!ned.block) return YAFFS_FAIL;
+
+
+
+
+
+ for(i=fail=0; i <nBlocks; i++)
+ {
+
+ nandemul_Block *blk;
+
+ if(!(blk = ned.block[i] = YMALLOC(sizeof(nandemul_Block))))
+ {
+ fail = 1;
+ }
+ else
+ {
+ for(j = 0; j < PAGES_PER_BLOCK; j++)
+ {
+ if((blk->page[j] = YMALLOC(sizeof(nandemul_Page))) == 0)
+ {
+ fail = 1;
+ }
+ }
+ nandemul_ReallyEraseBlock(i);
+ ned.block[i]->damaged = 0;
+ nAllocated++;
+ }
+ }
+
+ if(fail)
+ {
+ //Todo thump pages
+
+ for(i = 0; i < nAllocated; i++)
+ {
+ YFREE(ned.block[i]);
+ }
+ YFREE(ned.block);
+
+ T(YAFFS_TRACE_ALWAYS,("Allocation failed, could only allocate %dMB of %dMB requested.\n",
+ nAllocated/64,sizeInMB));
+ return 0;
+ }
+
+ ned.nBlocks = nBlocks;
+
+ initialised = 1;
+
+ return 1;
+}
+
+int nandemul2k_WriteChunkWithTagsToNAND(yaffs_Device *dev,int chunkInNAND,const __u8 *data, yaffs_ExtendedTags *tags)
+{
+ int blk;
+ int pg;
+ int i;
+
+ __u8 *x;
+
+
+ blk = chunkInNAND/PAGES_PER_BLOCK;
+ pg = chunkInNAND%PAGES_PER_BLOCK;
+
+
+ if(data)
+ {
+ x = ned.block[blk]->page[pg]->data;
+
+ for(i = 0; i < PAGE_DATA_SIZE; i++)
+ {
+ x[i] &=data[i];
+ }
+
+ ned.block[blk]->page[pg]->empty = 0;
+ }
+
+
+ if(tags)
+ {
+ x = &ned.block[blk]->page[pg]->data[PAGE_DATA_SIZE];
+
+ yaffs_PackTags2((yaffs_PackedTags2 *)x,tags);
+
+ }
+
+ if(tags || data)
+ {
+ nandemul_yield(1);
+ }
+
+ return YAFFS_OK;
+}
+
+
+int nandemul2k_ReadChunkWithTagsFromNAND(yaffs_Device *dev,int chunkInNAND, __u8 *data, yaffs_ExtendedTags *tags)
+{
+ int blk;
+ int pg;
+
+ __u8 *x;
+
+
+
+ blk = chunkInNAND/PAGES_PER_BLOCK;
+ pg = chunkInNAND%PAGES_PER_BLOCK;
+
+
+ if(data)
+ {
+ memcpy(data,ned.block[blk]->page[pg]->data,PAGE_DATA_SIZE);
+ }
+
+
+ if(tags)
+ {
+ x = &ned.block[blk]->page[pg]->data[PAGE_DATA_SIZE];
+
+ yaffs_UnpackTags2(tags,(yaffs_PackedTags2 *)x);
+ }
+
+ return YAFFS_OK;
+}
+
+
+static int nandemul2k_CheckChunkErased(yaffs_Device *dev,int chunkInNAND)
+{
+ int blk;
+ int pg;
+ int i;
+
+
+
+ blk = chunkInNAND/PAGES_PER_BLOCK;
+ pg = chunkInNAND%PAGES_PER_BLOCK;
+
+
+ for(i = 0; i < PAGE_TOTAL_SIZE; i++)
+ {
+ if(ned.block[blk]->page[pg]->data[i] != 0xFF)
+ {
+ return YAFFS_FAIL;
+ }
+ }
+
+ return YAFFS_OK;
+
+}
+
+int nandemul2k_EraseBlockInNAND(yaffs_Device *dev, int blockNumber)
+{
+
+
+ if(blockNumber < 0 || blockNumber >= ned.nBlocks)
+ {
+ T(YAFFS_TRACE_ALWAYS,("Attempt to erase non-existant block %d\n",blockNumber));
+ }
+ else if(ned.block[blockNumber]->damaged)
+ {
+ T(YAFFS_TRACE_ALWAYS,("Attempt to erase damaged block %d\n",blockNumber));
+ }
+ else
+ {
+ nandemul_ReallyEraseBlock(blockNumber);
+ }
+
+ return YAFFS_OK;
+}
+
+int nandemul2k_InitialiseNAND(yaffs_Device *dev)
+{
+ CheckInit();
+ return YAFFS_OK;
+}
+
+int nandemul2k_MarkNANDBlockBad(struct yaffs_DeviceStruct *dev, int blockNo)
+{
+
+ __u8 *x;
+
+ x = &ned.block[blockNo]->page[0]->data[PAGE_DATA_SIZE];
+
+ memset(x,0,sizeof(yaffs_PackedTags2));
+
+
+ return YAFFS_OK;
+
+}
+
+int nandemul2k_QueryNANDBlock(struct yaffs_DeviceStruct *dev, int blockNo, yaffs_BlockState *state, int *sequenceNumber)
+{
+ yaffs_ExtendedTags tags;
+ int chunkNo;
+
+ *sequenceNumber = 0;
+
+ chunkNo = blockNo * dev->nChunksPerBlock;
+
+ nandemul2k_ReadChunkWithTagsFromNAND(dev,chunkNo,NULL,&tags);
+ if(tags.blockBad)
+ {
+ *state = YAFFS_BLOCK_STATE_DEAD;
+ }
+ else if(!tags.chunkUsed)
+ {
+ *state = YAFFS_BLOCK_STATE_EMPTY;
+ }
+ else if(tags.chunkUsed)
+ {
+ *state = YAFFS_BLOCK_STATE_NEEDS_SCANNING;
+ *sequenceNumber = tags.sequenceNumber;
+ }
+ return YAFFS_OK;
+}
+
+int nandemul2k_GetBytesPerChunk(void) { return PAGE_DATA_SIZE;}
+
+int nandemul2k_GetChunksPerBlock(void) { return PAGES_PER_BLOCK; }
+int nandemul2k_GetNumberOfBlocks(void) {return nandemul2k_CalcNBlocks();}
+
+
+#endif //YAFFS_RAM_ENABLED
+
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