yaffs_guts.h
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- /*
- * 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 <charles@aleph1.co.uk>
- *
- * 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 1.18 2004/10/20 20:12:43 charles Exp $
- */
- #ifndef __YAFFS_GUTS_H__
- #define __YAFFS_GUTS_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
-
- #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)
- #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
- #define YAFFS_MAX_NAME_LENGTH 255
- #define YAFFS_SHORT_NAME_LENGTH 15
- #define YAFFS_MAX_ALIAS_LENGTH 159
- #define YAFFS_OBJECTID_ROOT 1
- #define YAFFS_OBJECTID_LOSTNFOUND 2
- #define YAFFS_OBJECTID_UNLINKED 3
- #define YAFFS_MAX_SHORT_OP_CACHES 20
- // 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
- __u8 data[YAFFS_BYTES_PER_CHUNK];
- } yaffs_ChunkCache;
- // 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;
- // 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;
- };
- // Block data in RAM
- typedef enum {
- YAFFS_BLOCK_STATE_UNKNOWN = 0,
- YAFFS_BLOCK_STATE_SCANNING, // Used while the block is being scanned.
- // NB Don't erase blocks while they're being scanned
-
- 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_DEAD // This block has failed and is not in use
- } yaffs_BlockState;
- typedef struct
- {
- #ifndef CONFIG_YAFFS_NO_YAFFS2
- __u32 sequenceNumber; // block sequence number for yaffs2
- #endif
- 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.
- } 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
- char 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.
- char 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[6];
- #else
- __u32 roomToGrow[12];
- #endif
-
- } 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
- {
- char *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
- char 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;
- __u8 deferedFree; // YAFFS has removed the object from NAND, but it is being kept
- // Alive until the inode is cleared to prevent inode inconsistencies.
- #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;
- //////////////////// 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 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 useNANDECC; // Flag to decide whether or not to use NANDECC
- int nShortOpCaches; // If <= 0, then short op caching is disabled, else
- // the number of short op caches (don't use too many).
-
-
- void *genericDevice; // Pointer to device context
- // On an mtd this holds the mtd pointer.
- // NAND access functions (Must be set before calling YAFFS)
-
- int (*writeChunkToNAND)(struct yaffs_DeviceStruct *dev,int chunkInNAND, const __u8 *data, 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);
- // 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
-
-
- // Operations since mount
- int nPageWrites;
- int nPageReads;
- int nBlockErasures;
- 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 *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;
-
- };
- typedef struct yaffs_DeviceStruct yaffs_Device;
- //////////// 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 char *oldName, yaffs_Object *newDir, const char *newName);
- // generic Object functions
- int yaffs_Unlink(yaffs_Object *dir, const char *name);
- int yaffs_DeleteFile(yaffs_Object *obj);
- // Object access functions.
- int yaffs_GetObjectName(yaffs_Object *obj,char *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 char *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 char *name, __u32 mode, __u32 uid, __u32 gid);
- yaffs_Object *yaffs_FindObjectByName(yaffs_Object *theDir,const char *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 char *name, yaffs_Object *equivalentObject);
- yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object *obj);
- // Symlink operations
- yaffs_Object *yaffs_MknodSymLink(yaffs_Object *parent, const char *name, __u32 mode, __u32 uid, __u32 gid, const char *alias);
- char *yaffs_GetSymlinkAlias(yaffs_Object *obj);
- // Special inodes (fifos, sockets and devices)
- yaffs_Object *yaffs_MknodSpecial(yaffs_Object *parent,const char *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
- #ifdef __KERNEL__
- void yaffs_HandleDeferedFree(yaffs_Object *obj);
- #endif
- // Debug dump
- int yaffs_DumpObject(yaffs_Object *obj);
- void yaffs_GutsTest(yaffs_Device *dev);
- #endif