2 * YAFFS: Yet another FFS. A NAND-flash specific file system.
3 * yaffs_guts.h: Configuration etc for yaffs_guts
5 * Copyright (C) 2002 Aleph One Ltd.
6 * for Toby Churchill Ltd and Brightstar Engineering
8 * Created by Charles Manning <charles@aleph1.co.uk>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU Lesser General Public License version 2.1 as
12 * published by the Free Software Foundation.
15 * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
17 * $Id: yaffs_guts.h,v 1.13 2002-12-13 00:13:06 charles Exp $
20 #ifndef __YAFFS_GUTS_H__
21 #define __YAFFS_GUTS_H__
23 #include "devextras.h"
33 // And what have we got...
34 #define YAFFS_MAGIC 0x5941FF53
36 #define YAFFS_NTNODES_LEVEL0 16
37 #define YAFFS_TNODES_LEVEL0_BITS 4
38 #define YAFFS_TNODES_LEVEL0_MASK 0xf
40 #define YAFFS_NTNODES_INTERNAL (YAFFS_NTNODES_LEVEL0 / 2)
41 #define YAFFS_TNODES_INTERNAL_BITS (YAFFS_TNODES_LEVEL0_BITS - 1)
42 #define YAFFS_TNODES_INTERNAL_MASK 0x7
43 #define YAFFS_TNODES_MAX_LEVEL 6
45 #define YAFFS_BYTES_PER_CHUNK 512
46 #define YAFFS_CHUNK_SIZE_SHIFT 9
48 #define YAFFS_BYTES_PER_SPARE 16
50 #define YAFFS_CHUNKS_PER_BLOCK 32
51 #define YAFFS_BYTES_PER_BLOCK (YAFFS_CHUNKS_PER_BLOCK*YAFFS_BYTES_PER_CHUNK)
53 #define YAFFS_MAX_CHUNK_ID 0x000FFFFF
55 #define YAFFS_UNUSED_OBJECT_ID 0x0003FFFF
57 #define YAFFS_ALLOCATION_NOBJECTS 100
58 #define YAFFS_ALLOCATION_NTNODES 100
59 #define YAFFS_ALLOCATION_NLINKS 100
61 #define YAFFS_NOBJECT_BUCKETS 256
64 #define YAFFS_RESERVED_BLOCKS 8
66 #define YAFFS_OBJECT_SPACE 0x40000
67 #define YAFFS_MAX_NAME_LENGTH 255
68 #define YAFFS_SHORT_NAME_LENGTH 15
70 #define YAFFS_MAX_ALIAS_LENGTH 159
72 #define YAFFS_OBJECTID_ROOT 1
73 #define YAFFS_OBJECTID_LOSTNFOUND 2
74 #define YAFFS_OBJECTID_UNLINKED 3
76 #define YAFFS_N_CACHE_CHUNKS 10
78 #ifdef CONFIG_YAFFS_WINCE
80 // Force the short operation cache on for WinCE
82 #define CONFIG_YAFFS_SHORT_OP_CACHE
86 // ChunkCache is used for short read/write operations.
89 struct yaffs_ObjectStruct *object;
93 __u8 data[YAFFS_BYTES_PER_CHUNK];
96 // Tags structures in RAM
97 // NB This uses bitfield. Bitfields should not stradle a u32 boundary otherwise
98 // the structure size will get blown out.
103 unsigned serialNumber:2;
104 unsigned byteCount:10;
105 unsigned objectId:18;
107 unsigned unusedStuff:2;
124 __u8 pageStatus; // set to 0 to delete the chunk
137 YAFFS_BLOCK_STATE_UddNKNOWN = 0,
138 YAFFS_BLOCK_STATE_SCANNING, // Used while the block is being scanned.
139 // NB Don't erase blocks while they're being scanned
141 YAFFS_BLOCK_STATE_EMPTY, // This block is empty
143 YAFFS_BLOCK_STATE_ALLOCATING, // This block is partially allocated.
144 // This is the one currently being used for page
145 // allocation. Should never be more than one of these
148 YAFFS_BLOCK_STATE_FULL, // All the pages in this block have been allocated.
149 // At least one page holds valid data.
151 YAFFS_BLOCK_STATE_DIRTY, // All pages have been allocated and deleted.
152 // Erase me, reuse me.
154 YAFFS_BLOCK_STATE_DEAD = 0x77 // This block has failed and is not in use
163 __u32 pageBits; // bitmap of pages in use
164 __u8 blockState; // One of the above block states
165 __u8 pagesInUse; // number of pages in use
166 __u8 needsRetiring:1; // Data has failed on this block, need to get valid data off
167 // and retire the block.
171 //////////////////// Object structure ///////////////////////////
172 // This is the object structure as stored on NAND
176 YAFFS_OBJECT_TYPE_UNKNOWN,
177 YAFFS_OBJECT_TYPE_FILE,
178 YAFFS_OBJECT_TYPE_SYMLINK,
179 YAFFS_OBJECT_TYPE_DIRECTORY,
180 YAFFS_OBJECT_TYPE_HARDLINK,
181 YAFFS_OBJECT_TYPE_SPECIAL
186 yaffs_ObjectType type;
188 // Apply to everything
190 __u16 sum__NoLongerUsed; // checksum of name. Calc this off the name to prevent inconsistencies
191 char name[YAFFS_MAX_NAME_LENGTH + 1];
193 // Thes following apply to directories, files, symlinks - not hard links
194 __u32 st_mode; // protection
196 #ifdef CONFIG_YAFFS_WINCE
197 __u32 notForWinCE[5];
199 __u32 st_uid; // user ID of owner
200 __u32 st_gid; // group ID of owner
201 __u32 st_atime; // time of last access
202 __u32 st_mtime; // time of last modification
203 __u32 st_ctime; // time of last change
206 // File size applies to files only
209 // Equivalent object id applies to hard links only.
210 int equivalentObjectId;
212 // Alias is for symlinks only.
213 char alias[YAFFS_MAX_ALIAS_LENGTH + 1];
215 __u32 st_rdev; // device stuff for block and char devices (maj/min)
217 #ifdef CONFIG_YAFFS_WINCE
223 __u32 roomToGrow[12];
226 } yaffs_ObjectHeader;
230 //////////////////// Tnode ///////////////////////////
232 union yaffs_Tnode_union
234 union yaffs_Tnode_union *internal[YAFFS_NTNODES_INTERNAL];
235 __u16 level0[YAFFS_NTNODES_LEVEL0];
239 typedef union yaffs_Tnode_union yaffs_Tnode;
241 struct yaffs_TnodeList_struct
243 struct yaffs_TnodeList_struct *next;
247 typedef struct yaffs_TnodeList_struct yaffs_TnodeList;
251 /////////////////// Object ////////////////////////////////
252 // An object can be one of:
253 // - a directory (no data, has children links
254 // - a regular file (data.... not prunes :->).
255 // - a symlink [symbolic link] (the alias).
262 __u32 scannedFileSize;
265 } yaffs_FileStructure;
269 struct list_head children; // list of child links
270 } yaffs_DirectoryStructure;
275 } yaffs_SymLinkStructure;
279 struct yaffs_ObjectStruct *equivalentObject;
280 __u32 equivalentObjectId;
281 } yaffs_HardLinkStructure;
285 yaffs_FileStructure fileVariant;
286 yaffs_DirectoryStructure directoryVariant;
287 yaffs_SymLinkStructure symLinkVariant;
288 yaffs_HardLinkStructure hardLinkVariant;
289 } yaffs_ObjectVariant;
292 struct yaffs_ObjectStruct
294 __u8 deleted: 1; // This should only apply to unlinked files.
295 __u8 unlinked: 1; // An unlinked file. The file should be in the unlinked pseudo directory.
296 __u8 fake:1; // A fake object has no presence on NAND.
297 __u8 renameAllowed:1;
298 __u8 unlinkAllowed:1;
299 __u8 dirty:1; // the object needs to be written to flash
300 __u8 valid:1; // When the file system is being loaded up, this
301 // object might be created before the data
302 // is available (ie. file data records appear before the header).
303 __u8 serial; // serial number of chunk in NAND. Store here so we don't have to
304 // read back the old one to update.
305 __u16 sum; // sum of the name to speed searching
307 struct yaffs_DeviceStruct *myDev; // The device I'm on
310 struct list_head hashLink; // list of objects in this hash bucket
313 struct list_head hardLinks; // all the equivalent hard linked objects
315 // directory structure stuff
316 struct yaffs_ObjectStruct *parent; //my parent directory
317 struct list_head siblings; // siblings in a directory
318 // also used for linking up the free list
320 // Where's my data in NAND?
321 int chunkId; // where it lives
325 __u32 objectId; // the object id value
328 __u32 st_mode; // protection
330 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
331 char shortName[YAFFS_SHORT_NAME_LENGTH+1];
334 #ifdef CONFIG_YAFFS_WINCE
341 __u32 st_uid; // user ID of owner
342 __u32 st_gid; // group ID of owner
343 __u32 st_atime; // time of last access
344 __u32 st_mtime; // time of last modification
345 __u32 st_ctime; // time of last change
346 __u32 st_rdev; // device stuff for block and char devices
353 struct inode *myInode;
358 yaffs_ObjectType variantType;
360 yaffs_ObjectVariant variant;
366 typedef struct yaffs_ObjectStruct yaffs_Object;
369 struct yaffs_ObjectList_struct
371 yaffs_Object *objects;
372 struct yaffs_ObjectList_struct *next;
375 typedef struct yaffs_ObjectList_struct yaffs_ObjectList;
379 struct list_head list;
381 } yaffs_ObjectBucket;
384 //////////////////// Device ////////////////////////////////
386 struct yaffs_DeviceStruct
388 // Entry parameters set up way early. Yaffs sets up the rest.
389 int startBlock; // Start block we're allowed to use
390 int endBlock; // End block we're allowed to use
391 __u16 chunkGroupBits; // 0 for devices <= 32MB. else log2(nchunks) - 16
392 __u16 chunkGroupSize; // == 2^^chunkGroupBits
395 void *genericDevice; // Pointer to device context
396 // On an mtd this holds the mtd pointer.
400 struct semaphore sem;// Semaphore for waiting on erasure.
401 struct semaphore grossLock; // Gross locking semaphore
406 // NAND access functions (Must be set before calling YAFFS)
408 int (*writeChunkToNAND)(struct yaffs_DeviceStruct *dev,int chunkInNAND, const __u8 *data, yaffs_Spare *spare);
409 int (*readChunkFromNAND)(struct yaffs_DeviceStruct *dev,int chunkInNAND, __u8 *data, yaffs_Spare *spare);
410 int (*eraseBlockInNAND)(struct yaffs_DeviceStruct *dev,int blockInNAND);
411 int (*initialiseNAND)(struct yaffs_DeviceStruct *dev);
414 void (*putSuperFunc)(struct super_block *sb);
417 // Runtime parameters.
418 yaffs_BlockInfo *blockInfo;
421 __u32 allocationPage;
422 int allocationBlockFinder;
426 yaffs_Tnode *freeTnodes;
428 yaffs_TnodeList *allocatedTnodeList;
432 yaffs_Object *freeObjects;
435 yaffs_ObjectList *allocatedObjectList;
437 yaffs_ObjectBucket objectBucket[YAFFS_NOBJECT_BUCKETS];
441 int currentDirtyChecker; // Used to find current dirtiest block
443 int garbageCollectionRequired;
445 // Operations since mount
450 int garbageCollections;
458 yaffs_Object *rootDir;
459 yaffs_Object *lostNFoundDir;
461 // Buffer areas for storing data to recover from write failures
462 __u8 bufferedData[YAFFS_CHUNKS_PER_BLOCK][YAFFS_BYTES_PER_CHUNK];
463 yaffs_Spare bufferedSpare[YAFFS_CHUNKS_PER_BLOCK];
464 int bufferedBlock; // Which block is buffered here?
465 int doingBufferedBlockRewrite;
467 int blockSelectedForGC;
469 #ifdef CONFIG_YAFFS_SHORT_OP_CACHE
470 yaffs_ChunkCache srCache[YAFFS_N_CACHE_CHUNKS];
475 // Stuff for background deletion and unlinked files.
476 yaffs_Object *unlinkedDir; // Directory where unlinked and deleted files live.
477 yaffs_Object *unlinkedDeletion; // Current file being background deleted.
478 int nDeletedFiles; // Count of files awaiting deletion;
479 int nUnlinkedFiles; // Count of unlinked files.
480 int nBackgroundDeletions; // Count of background deletions.
486 typedef struct yaffs_DeviceStruct yaffs_Device;
490 //////////// YAFFS Functions //////////////////
492 int yaffs_GutsInitialise(yaffs_Device *dev);
493 void yaffs_Deinitialise(yaffs_Device *dev);
495 int yaffs_GetNumberOfFreeChunks(yaffs_Device *dev);
499 int yaffs_RenameObject(yaffs_Object *oldDir, const char *oldName, yaffs_Object *newDir, const char *newName);
501 // generic Object functions
502 int yaffs_Unlink(yaffs_Object *dir, const char *name);
503 int yaffs_DeleteFile(yaffs_Object *obj);
505 // Object access functions.
506 int yaffs_GetObjectName(yaffs_Object *obj,char *name,int buffSize);
507 int yaffs_GetObjectFileLength(yaffs_Object *obj);
508 int yaffs_GetObjectInode(yaffs_Object *obj);
509 unsigned yaffs_GetObjectType(yaffs_Object *obj);
510 int yaffs_GetObjectLinkCount(yaffs_Object *obj);
512 // Change inode attributes
513 int yaffs_SetAttributes(yaffs_Object *obj, struct iattr *attr);
514 int yaffs_GetAttributes(yaffs_Object *obj, struct iattr *attr);
517 int yaffs_ReadDataFromFile(yaffs_Object *obj, __u8 *buffer, __u32 offset, int nBytes);
518 int yaffs_WriteDataToFile(yaffs_Object *obj, const __u8 *buffer, __u32 offset, int nBytes);
519 int yaffs_ResizeFile(yaffs_Object *obj, int newSize);
521 yaffs_Object *yaffs_MknodFile(yaffs_Object *parent,const char *name, __u32 mode, __u32 uid, __u32 gid);
522 int yaffs_FlushFile(yaffs_Object *obj);
525 // Directory operations
526 yaffs_Object *yaffs_MknodDirectory(yaffs_Object *parent,const char *name, __u32 mode, __u32 uid, __u32 gid);
527 yaffs_Object *yaffs_FindObjectByName(yaffs_Object *theDir,const char *name);
528 int yaffs_ApplyToDirectoryChildren(yaffs_Object *theDir,int (*fn)(yaffs_Object *));
530 yaffs_Object *yaffs_FindObjectByNumber(yaffs_Device *dev,__u32 number);
533 yaffs_Object *yaffs_Link(yaffs_Object *parent, const char *name, yaffs_Object *equivalentObject);
535 yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object *obj);
537 // Symlink operations
538 yaffs_Object *yaffs_MknodSymLink(yaffs_Object *parent, const char *name, __u32 mode, __u32 uid, __u32 gid, const char *alias);
539 char *yaffs_GetSymlinkAlias(yaffs_Object *obj);
541 // Special inodes (fifos, sockets and devices)
542 yaffs_Object *yaffs_MknodSpecial(yaffs_Object *parent,const char *name, __u32 mode, __u32 uid, __u32 gid,__u32 rdev);
545 // Special directories
546 yaffs_Object *yaffs_Root(yaffs_Device *dev);
547 yaffs_Object *yaffs_LostNFound(yaffs_Device *dev);
549 #ifdef CONFIG_YAFFS_WINCE
550 // CONFIG_YAFFS_WINCE special stuff
551 void yfsd_WinFileTimeNow(__u32 target[2]);
556 int yaffs_DumpObject(yaffs_Object *obj);
559 void yaffs_GutsTest(yaffs_Device *dev);