www.pudn.com > yaffs2.zip > yaffs_guts.h
/*
* YAFFS: Yet another FFS. A NAND-flash specific file system.
* yaffs_guts.h: Configuration etc for yaffs_guts
*
* Copyright (C) 2002 Aleph One Ltd.
* for Toby Churchill Ltd and Brightstar Engineering
*
* Created by Charles Manning
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version 2.1 as
* published by the Free Software Foundation.
*
*
* Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
*
* $Id: yaffs_guts.h,v 1.1 2004/11/03 08:14:07 charles Exp $
*/
#ifndef __YAFFS_GUTS_H__
#define __YAFFS_GUTS_H__
#include "devextras.h"
#include "yportenv.h"
#define YAFFS_OK 1
#define YAFFS_FAIL 0
// Give us a Y=0x59,
// Give us an A=0x41,
// Give us an FF=0xFF
// Give us an S=0x53
// And what have we got...
#define YAFFS_MAGIC 0x5941FF53
#define YAFFS_NTNODES_LEVEL0 16
#define YAFFS_TNODES_LEVEL0_BITS 4
#define YAFFS_TNODES_LEVEL0_MASK 0xf
#define YAFFS_NTNODES_INTERNAL (YAFFS_NTNODES_LEVEL0 / 2)
#define YAFFS_TNODES_INTERNAL_BITS (YAFFS_TNODES_LEVEL0_BITS - 1)
#define YAFFS_TNODES_INTERNAL_MASK 0x7
#define YAFFS_TNODES_MAX_LEVEL 6
#ifndef CONFIG_YAFFS_NO_YAFFS1
#define YAFFS_BYTES_PER_SPARE 16
#define YAFFS_BYTES_PER_CHUNK 512
#define YAFFS_CHUNK_SIZE_SHIFT 9
#define YAFFS_CHUNKS_PER_BLOCK 32
#define YAFFS_BYTES_PER_BLOCK (YAFFS_CHUNKS_PER_BLOCK*YAFFS_BYTES_PER_CHUNK)
#endif
#define YAFFS_MAX_CHUNK_ID 0x000FFFFF
#define YAFFS_UNUSED_OBJECT_ID 0x0003FFFF
#define YAFFS_ALLOCATION_NOBJECTS 100
#define YAFFS_ALLOCATION_NTNODES 100
#define YAFFS_ALLOCATION_NLINKS 100
#define YAFFS_NOBJECT_BUCKETS 256
#define YAFFS_OBJECT_SPACE 0x40000
#ifdef CONFIG_YAFFS_UNICODE
#define YAFFS_MAX_NAME_LENGTH 127
#define YAFFS_MAX_ALIAS_LENGTH 79
#else
#define YAFFS_MAX_NAME_LENGTH 255
#define YAFFS_MAX_ALIAS_LENGTH 159
#endif
#define YAFFS_SHORT_NAME_LENGTH 15
#define YAFFS_OBJECTID_ROOT 1
#define YAFFS_OBJECTID_LOSTNFOUND 2
#define YAFFS_OBJECTID_UNLINKED 3
#define YAFFS_OBJECTID_DELETED 4
#define YAFFS_MAX_SHORT_OP_CACHES 20
#define YAFFS_N_TEMP_BUFFERS 4
// Sequence numbers are used in YAFFS2 to determine block allocation order.
// The range is limited slightly to help distinguish bad numbers from good.
// This also allows us to perhaps in the future use special numbers for
// special purposes.
// EFFFFF00 allows the allocation of 8 blocks per second (~1Mbytes) for 15 years,
// and is a larger number than the lifetime of a 2GB device.
#define YAFFS_LOWEST_SEQUENCE_NUMBER 0x00001000
#define YAFFS_HIGHEST_SEQUENCE_NUMBER 0xEFFFFF00
// ChunkCache is used for short read/write operations.
typedef struct
{
struct yaffs_ObjectStruct *object;
int chunkId;
int lastUse;
int dirty;
int nBytes; // Only valid if the cache is dirty
int locked; // Can't push out or flush while locked..
#ifdef YAFFS2_DEFINES
__u8 *data;
#else
__u8 data[YAFFS_BYTES_PER_CHUNK];
#endif
} yaffs_ChunkCache;
#ifndef CONFIG_YAFFS_NO_YAFFS1
// Tags structures in RAM
// NB This uses bitfield. Bitfields should not straddle a u32 boundary otherwise
// the structure size will get blown out.
typedef struct
{
unsigned chunkId:20;
unsigned serialNumber:2;
unsigned byteCount:10;
unsigned objectId:18;
unsigned ecc:12;
unsigned unusedStuff:2;
} yaffs_Tags;
typedef union
{
yaffs_Tags asTags;
__u8 asBytes[8];
} yaffs_TagsUnion;
#endif
typedef enum
{
YAFFS_ECC_RESULT_UNKNOWN,
YAFFS_ECC_RESULT_NO_ERROR,
YAFFS_ECC_RESULT_FIXED,
YAFFS_ECC_RESULT_UNFIXED
} yaffs_ECCResult;
typedef struct
{
unsigned validMarker0;
unsigned chunkUsed; // Status of the chunk: used or unused
unsigned objectId; // If 0 then this is not part of an object (unused)
unsigned chunkId; // If 0 then this is a header
unsigned byteCount; // Only valid for data chunks
// The following stuff only has meaning when we read
yaffs_ECCResult eccResult; // Only valid when we read.
unsigned blockBad; // Only valid on reading
// YAFFS 1 stuff
unsigned chunkDeleted; // The chunk is marked deleted
unsigned serialNumber; // Yaffs1 2-bit serial number
// YAFFS2 stuff
unsigned sequenceNumber; // The sequence number of this block
unsigned validMarker1;
} yaffs_ExtendedTags;
#ifndef CONFIG_YAFFS_NO_YAFFS1
// Spare structure
typedef struct
{
__u8 tagByte0;
__u8 tagByte1;
__u8 tagByte2;
__u8 tagByte3;
__u8 pageStatus; // set to 0 to delete the chunk
__u8 blockStatus;
__u8 tagByte4;
__u8 tagByte5;
__u8 ecc1[3];
__u8 tagByte6;
__u8 tagByte7;
__u8 ecc2[3];
} yaffs_Spare;
//Special structure for passing through to mtd
struct yaffs_NANDSpare {
yaffs_Spare spare;
int eccres1;
int eccres2;
};
#endif
// Block data in RAM
typedef enum {
YAFFS_BLOCK_STATE_UNKNOWN = 0,
#ifndef YAFFS2_DEFINES
YAFFS_BLOCK_STATE_SCANNING,
#else
YAFFS_BLOCK_STATE_NEEDS_SCANNING,// The block might have something on it (ie it is allocating or full, perhaps empty)
// but it needs to be scanned to determine its true state.
// This state is only valid during yaffs_Scan.
// NB We tolerate empty because the pre-scanner might be incapable of deciding
// However, if this state is returned on a YAFFS2 device, then we expect a sequence number
#endif
YAFFS_BLOCK_STATE_EMPTY, // This block is empty
YAFFS_BLOCK_STATE_ALLOCATING, // This block is partially allocated.
// This is the one currently being used for page
// allocation. Should never be more than one of these
YAFFS_BLOCK_STATE_FULL, // All the pages in this block have been allocated.
// At least one page holds valid data.
YAFFS_BLOCK_STATE_DIRTY, // All pages have been allocated and deleted.
// Erase me, reuse me.
YAFFS_BLOCK_STATE_COLLECTING, // This block is being garbage collected
YAFFS_BLOCK_STATE_DEAD // This block has failed and is not in use
} yaffs_BlockState;
typedef struct
{
int softDeletions:8; // number of soft deleted pages
int pagesInUse:8; // number of pages in use
__u32 blockState:4; // One of the above block states
__u32 needsRetiring:1; // Data has failed on this block, need to get valid data off
// and retire the block.
#ifndef CONFIG_YAFFS_NO_YAFFS2
__u32 hasShrinkHeader:1;// This block has at least one object header that does a shrink
__u32 sequenceNumber; // block sequence number for yaffs2
#endif
} yaffs_BlockInfo;
//////////////////// Object structure ///////////////////////////
// This is the object structure as stored on NAND
typedef enum
{
YAFFS_OBJECT_TYPE_UNKNOWN,
YAFFS_OBJECT_TYPE_FILE,
YAFFS_OBJECT_TYPE_SYMLINK,
YAFFS_OBJECT_TYPE_DIRECTORY,
YAFFS_OBJECT_TYPE_HARDLINK,
YAFFS_OBJECT_TYPE_SPECIAL
} yaffs_ObjectType;
typedef struct
{
yaffs_ObjectType type;
// Apply to everything
int parentObjectId;
__u16 sum__NoLongerUsed; // checksum of name. Calc this off the name to prevent inconsistencies
YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
// Thes following apply to directories, files, symlinks - not hard links
__u32 st_mode; // protection
#ifdef CONFIG_YAFFS_WINCE
__u32 notForWinCE[5];
#else
__u32 st_uid; // user ID of owner
__u32 st_gid; // group ID of owner
__u32 st_atime; // time of last access
__u32 st_mtime; // time of last modification
__u32 st_ctime; // time of last change
#endif
// File size applies to files only
int fileSize;
// Equivalent object id applies to hard links only.
int equivalentObjectId;
// Alias is for symlinks only.
YCHAR alias[YAFFS_MAX_ALIAS_LENGTH + 1];
__u32 st_rdev; // device stuff for block and char devices (maj/min)
#ifdef CONFIG_YAFFS_WINCE
__u32 win_ctime[2];
__u32 win_atime[2];
__u32 win_mtime[2];
__u32 roomToGrow[5];
#else
__u32 roomToGrow[11];
#endif
// isShrink applies to bject headers written when we shrink the file (ie resize)
__u32 isShrink;
} yaffs_ObjectHeader;
//////////////////// Tnode ///////////////////////////
union yaffs_Tnode_union
{
#ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
union yaffs_Tnode_union *internal[YAFFS_NTNODES_INTERNAL+1];
#else
union yaffs_Tnode_union *internal[YAFFS_NTNODES_INTERNAL];
#endif
__u16 level0[YAFFS_NTNODES_LEVEL0];
};
typedef union yaffs_Tnode_union yaffs_Tnode;
struct yaffs_TnodeList_struct
{
struct yaffs_TnodeList_struct *next;
yaffs_Tnode *tnodes;
};
typedef struct yaffs_TnodeList_struct yaffs_TnodeList;
/////////////////// Object ////////////////////////////////
// An object can be one of:
// - a directory (no data, has children links
// - a regular file (data.... not prunes :->).
// - a symlink [symbolic link] (the alias).
// - a hard link
typedef struct
{
__u32 fileSize;
__u32 scannedFileSize;
int topLevel;
yaffs_Tnode *top;
} yaffs_FileStructure;
typedef struct
{
struct list_head children; // list of child links
} yaffs_DirectoryStructure;
typedef struct
{
YCHAR *alias;
} yaffs_SymLinkStructure;
typedef struct
{
struct yaffs_ObjectStruct *equivalentObject;
__u32 equivalentObjectId;
} yaffs_HardLinkStructure;
typedef union
{
yaffs_FileStructure fileVariant;
yaffs_DirectoryStructure directoryVariant;
yaffs_SymLinkStructure symLinkVariant;
yaffs_HardLinkStructure hardLinkVariant;
} yaffs_ObjectVariant;
struct yaffs_ObjectStruct
{
__u8 deleted: 1; // This should only apply to unlinked files.
__u8 softDeleted: 1; // it has also been soft deleted
__u8 unlinked: 1; // An unlinked file. The file should be in the unlinked pseudo directory.
__u8 fake:1; // A fake object has no presence on NAND.
__u8 renameAllowed:1;
__u8 unlinkAllowed:1;
__u8 dirty:1; // the object needs to be written to flash
__u8 valid:1; // When the file system is being loaded up, this
// object might be created before the data
// is available (ie. file data records appear before the header).
__u8 serial; // serial number of chunk in NAND. Store here so we don't have to
// read back the old one to update.
__u16 sum; // sum of the name to speed searching
struct yaffs_DeviceStruct *myDev; // The device I'm on
struct list_head hashLink; // list of objects in this hash bucket
struct list_head hardLinks; // all the equivalent hard linked objects
// live on this list
// directory structure stuff
struct yaffs_ObjectStruct *parent; //my parent directory
struct list_head siblings; // siblings in a directory
// also used for linking up the free list
// Where's my data in NAND?
int chunkId; // where it lives
int nDataChunks;
__u32 objectId; // the object id value
__u32 st_mode; // protection
#ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
YCHAR shortName[YAFFS_SHORT_NAME_LENGTH+1];
#endif
#ifndef __KERNEL__
__u32 inUse;
#endif
#ifdef CONFIG_YAFFS_WINCE
__u32 win_ctime[2];
__u32 win_mtime[2];
__u32 win_atime[2];
#else
__u32 st_uid; // user ID of owner
__u32 st_gid; // group ID of owner
__u32 st_atime; // time of last access
__u32 st_mtime; // time of last modification
__u32 st_ctime; // time of last change
#endif
__u32 st_rdev; // device stuff for block and char devices
#ifdef __KERNEL__
struct inode *myInode;
#endif
yaffs_ObjectType variantType;
yaffs_ObjectVariant variant;
};
typedef struct yaffs_ObjectStruct yaffs_Object;
struct yaffs_ObjectList_struct
{
yaffs_Object *objects;
struct yaffs_ObjectList_struct *next;
};
typedef struct yaffs_ObjectList_struct yaffs_ObjectList;
typedef struct
{
struct list_head list;
int count;
} yaffs_ObjectBucket;
///////////////////// Temporary buffers ////////////////////
//
// These are chunk-sized working buffers. Each device has a few
typedef struct {
__u8 *buffer;
int line; // track from whence this buffer was allocated
int maxLine;
} yaffs_TempBuffer;
//////////////////// Device ////////////////////////////////
struct yaffs_DeviceStruct
{
// Entry parameters set up way early. Yaffs sets up the rest.
int nBytesPerChunk; // Should be a power of 2 >= 512
int nChunksPerBlock; // does not need to be a power of 2
int nBytesPerSpare; // spare area size
int startBlock; // Start block we're allowed to use
int endBlock; // End block we're allowed to use
int nReservedBlocks; // We want this tuneable so that we can reduce
// reserved blocks on NOR and RAM.
int nShortOpCaches; // If <= 0, then short op caching is disabled, else
// the number of short op caches (don't use too many).
int useHeaderFileSize; // Flag to determine if we should use file sizes from the header
int useNANDECC; // Flag to decide whether or not to use NANDECC
void *genericDevice; // Pointer to device context
// On an mtd this holds the mtd pointer.
// NAND access functions (Must be set before calling YAFFS)
#ifndef CONFIG_YAFFS_NO_YAFFS1
int (*writeChunkToNAND)(struct yaffs_DeviceStruct *dev,int chunkInNAND, const __u8 *data, const yaffs_Spare *spare);
int (*readChunkFromNAND)(struct yaffs_DeviceStruct *dev,int chunkInNAND, __u8 *data, yaffs_Spare *spare);
// int (*eraseBlockInNAND)(struct yaffs_DeviceStruct *dev,int blockInNAND);
// int (*initialiseNAND)(struct yaffs_DeviceStruct *dev);
#endif
#ifndef CONFIG_YAFFS_NO_YAFFS2
int (*writeChunkWithTagsToNAND)(struct yaffs_DeviceStruct *dev,int chunkInNAND, const __u8 *data, yaffs_ExtendedTags *tags);
int (*readChunkWithTagsFromNAND)(struct yaffs_DeviceStruct *dev,int chunkInNAND, __u8 *data, yaffs_ExtendedTags *tags);
int (*eraseBlockInNAND)(struct yaffs_DeviceStruct *dev,int blockInNAND);
int (*initialiseNAND)(struct yaffs_DeviceStruct *dev);
int (*markNANDBlockBad)(struct yaffs_DeviceStruct *dev, int blockNo);
int (*queryNANDBlock)(struct yaffs_DeviceStruct *dev, int blockNo, yaffs_BlockState *state, int *sequenceNumber);
#endif
int isYaffs2;
// End of stuff that must be set before initialisation.
// Runtime parameters. Set up by YAFFS.
__u16 chunkGroupBits; // 0 for devices <= 32MB. else log2(nchunks) - 16
__u16 chunkGroupSize; // == 2^^chunkGroupBits
#ifdef __KERNEL__
struct semaphore sem;// Semaphore for waiting on erasure.
struct semaphore grossLock; // Gross locking semaphore
#endif
#ifdef __KERNEL__
void (*putSuperFunc)(struct super_block *sb);
#endif
int isMounted;
// Block Info
yaffs_BlockInfo *blockInfo;
__u8 *chunkBits; // bitmap of chunks in use
int chunkBitmapStride; // Number of bytes of chunkBits per block.
// Must be consistent with nChunksPerBlock.
int nErasedBlocks;
int allocationBlock; // Current block being allocated off
__u32 allocationPage;
int allocationBlockFinder; // Used to search for next allocation block
// Runtime state
int nTnodesCreated;
yaffs_Tnode *freeTnodes;
int nFreeTnodes;
yaffs_TnodeList *allocatedTnodeList;
int nObjectsCreated;
yaffs_Object *freeObjects;
int nFreeObjects;
yaffs_ObjectList *allocatedObjectList;
yaffs_ObjectBucket objectBucket[YAFFS_NOBJECT_BUCKETS];
int nFreeChunks;
int currentDirtyChecker; // Used to find current dirtiest block
__u32 *gcCleanupList; // objects to delete at the end of a GC.
// Operations since mount
int nPageWrites;
int nPageReads;
int nBlockErasures;
int nErasureFailures;
int nGCCopies;
int garbageCollections;
int passiveGarbageCollections;
int nRetriedWrites;
int nRetiredBlocks;
int eccFixed;
int eccUnfixed;
int tagsEccFixed;
int tagsEccUnfixed;
int nDeletions;
int nUnmarkedDeletions;
yaffs_Object *rootDir;
yaffs_Object *lostNFoundDir;
// Buffer areas for storing data to recover from write failures
// __u8 bufferedData[YAFFS_CHUNKS_PER_BLOCK][YAFFS_BYTES_PER_CHUNK];
// yaffs_Spare bufferedSpare[YAFFS_CHUNKS_PER_BLOCK];
int bufferedBlock; // Which block is buffered here?
int doingBufferedBlockRewrite;
yaffs_ChunkCache *srCache;
int srLastUse;
int cacheHits;
// Stuff for background deletion and unlinked files.
yaffs_Object *unlinkedDir; // Directory where unlinked and deleted files live.
yaffs_Object *deletedDir; // Directory where deleted objects are sent to disappear.
yaffs_Object *unlinkedDeletion; // Current file being background deleted.
int nDeletedFiles; // Count of files awaiting deletion;
int nUnlinkedFiles; // Count of unlinked files.
int nBackgroundDeletions; // Count of background deletions.
//__u8 *localBuffer;
yaffs_TempBuffer tempBuffer[YAFFS_N_TEMP_BUFFERS];
int maxTemp;
int unmanagedTempAllocations;
int unmanagedTempDeallocations;
// yaffs2 runtime stuff
unsigned sequenceNumber; //Sequence number of currently allocating block
unsigned oldestDirtySequence;
};
typedef struct yaffs_DeviceStruct yaffs_Device;
// Function to manipulate block info
static Y_INLINE yaffs_BlockInfo* yaffs_GetBlockInfo(yaffs_Device *dev, int blk)
{
if(blk < dev->startBlock || blk > dev->endBlock)
{
T(YAFFS_TRACE_ERROR,(TSTR("**>> yaffs: getBlockInfo block %d is not valid" TENDSTR),blk));
YBUG();
}
return &dev->blockInfo[blk - dev->startBlock];
}
//////////// YAFFS Functions //////////////////
int yaffs_GutsInitialise(yaffs_Device *dev);
void yaffs_Deinitialise(yaffs_Device *dev);
int yaffs_GetNumberOfFreeChunks(yaffs_Device *dev);
// Rename
int yaffs_RenameObject(yaffs_Object *oldDir, const YCHAR *oldName, yaffs_Object *newDir, const YCHAR *newName);
// generic Object functions
int yaffs_Unlink(yaffs_Object *dir, const YCHAR *name);
int yaffs_DeleteFile(yaffs_Object *obj);
// Object access functions.
int yaffs_GetObjectName(yaffs_Object *obj,YCHAR *name,int buffSize);
int yaffs_GetObjectFileLength(yaffs_Object *obj);
int yaffs_GetObjectInode(yaffs_Object *obj);
unsigned yaffs_GetObjectType(yaffs_Object *obj);
int yaffs_GetObjectLinkCount(yaffs_Object *obj);
// Change inode attributes
int yaffs_SetAttributes(yaffs_Object *obj, struct iattr *attr);
int yaffs_GetAttributes(yaffs_Object *obj, struct iattr *attr);
// File operations
int yaffs_ReadDataFromFile(yaffs_Object *obj, __u8 *buffer, __u32 offset, int nBytes);
int yaffs_WriteDataToFile(yaffs_Object *obj, const __u8 *buffer, __u32 offset, int nBytes);
int yaffs_ResizeFile(yaffs_Object *obj, int newSize);
yaffs_Object *yaffs_MknodFile(yaffs_Object *parent,const YCHAR *name, __u32 mode, __u32 uid, __u32 gid);
int yaffs_FlushFile(yaffs_Object *obj,int updateTime);
// Directory operations
yaffs_Object *yaffs_MknodDirectory(yaffs_Object *parent,const YCHAR *name, __u32 mode, __u32 uid, __u32 gid);
yaffs_Object *yaffs_FindObjectByName(yaffs_Object *theDir,const YCHAR *name);
int yaffs_ApplyToDirectoryChildren(yaffs_Object *theDir,int (*fn)(yaffs_Object *));
yaffs_Object *yaffs_FindObjectByNumber(yaffs_Device *dev,__u32 number);
// Link operations
yaffs_Object *yaffs_Link(yaffs_Object *parent, const YCHAR *name, yaffs_Object *equivalentObject);
yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object *obj);
// Symlink operations
yaffs_Object *yaffs_MknodSymLink(yaffs_Object *parent, const YCHAR *name, __u32 mode, __u32 uid, __u32 gid, const YCHAR *alias);
YCHAR *yaffs_GetSymlinkAlias(yaffs_Object *obj);
// Special inodes (fifos, sockets and devices)
yaffs_Object *yaffs_MknodSpecial(yaffs_Object *parent,const YCHAR *name, __u32 mode, __u32 uid, __u32 gid,__u32 rdev);
// Special directories
yaffs_Object *yaffs_Root(yaffs_Device *dev);
yaffs_Object *yaffs_LostNFound(yaffs_Device *dev);
#ifdef CONFIG_YAFFS_WINCE
// CONFIG_YAFFS_WINCE special stuff
void yfsd_WinFileTimeNow(__u32 target[2]);
#endif
// Debug dump
int yaffs_DumpObject(yaffs_Object *obj);
void yaffs_GutsTest(yaffs_Device *dev);
void yaffs_InitialiseTags(yaffs_ExtendedTags *tags);
void yaffs_DeleteChunk(yaffs_Device *dev,int chunkId,int markNAND,int lyn);
int yaffs_CheckFF(__u8 *buffer,int nBytes);
#endif