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 1.18 2006-01-27 00:44:10 charles Exp $
20 #ifndef __YAFFS_GUTS_H__
21 #define __YAFFS_GUTS_H__
23 #include "devextras.h"
33 * And what have we got...
35 #define YAFFS_MAGIC 0x5941FF53
37 #define YAFFS_NTNODES_LEVEL0 16
38 #define YAFFS_TNODES_LEVEL0_BITS 4
39 #define YAFFS_TNODES_LEVEL0_MASK 0xf
41 #define YAFFS_NTNODES_INTERNAL (YAFFS_NTNODES_LEVEL0 / 2)
42 #define YAFFS_TNODES_INTERNAL_BITS (YAFFS_TNODES_LEVEL0_BITS - 1)
43 #define YAFFS_TNODES_INTERNAL_MASK 0x7
44 #define YAFFS_TNODES_MAX_LEVEL 6
46 #ifndef CONFIG_YAFFS_NO_YAFFS1
47 #define YAFFS_BYTES_PER_SPARE 16
48 #define YAFFS_BYTES_PER_CHUNK 512
49 #define YAFFS_CHUNK_SIZE_SHIFT 9
50 #define YAFFS_CHUNKS_PER_BLOCK 32
51 #define YAFFS_BYTES_PER_BLOCK (YAFFS_CHUNKS_PER_BLOCK*YAFFS_BYTES_PER_CHUNK)
54 #define YAFFS_MIN_YAFFS2_CHUNK_SIZE 1024
55 #define YAFFS_MIN_YAFFS2_SPARE_SIZE 32
57 #define YAFFS_MAX_CHUNK_ID 0x000FFFFF
59 #define YAFFS_UNUSED_OBJECT_ID 0x0003FFFF
61 #define YAFFS_ALLOCATION_NOBJECTS 100
62 #define YAFFS_ALLOCATION_NTNODES 100
63 #define YAFFS_ALLOCATION_NLINKS 100
65 #define YAFFS_NOBJECT_BUCKETS 256
67 #define YAFFS_OBJECT_SPACE 0x40000
69 #ifdef CONFIG_YAFFS_UNICODE
70 #define YAFFS_MAX_NAME_LENGTH 127
71 #define YAFFS_MAX_ALIAS_LENGTH 79
73 #define YAFFS_MAX_NAME_LENGTH 255
74 #define YAFFS_MAX_ALIAS_LENGTH 159
77 #define YAFFS_SHORT_NAME_LENGTH 15
79 /* Some special object ids */
80 #define YAFFS_OBJECTID_ROOT 1
81 #define YAFFS_OBJECTID_LOSTNFOUND 2
82 #define YAFFS_OBJECTID_UNLINKED 3
83 #define YAFFS_OBJECTID_DELETED 4
85 #define YAFFS_MAX_SHORT_OP_CACHES 20
87 #define YAFFS_N_TEMP_BUFFERS 4
89 /* Sequence numbers are used in YAFFS2 to determine block allocation order.
90 * The range is limited slightly to help distinguish bad numbers from good.
91 * This also allows us to perhaps in the future use special numbers for
93 * EFFFFF00 allows the allocation of 8 blocks per second (~1Mbytes) for 15 years,
94 * and is a larger number than the lifetime of a 2GB device.
96 #define YAFFS_LOWEST_SEQUENCE_NUMBER 0x00001000
97 #define YAFFS_HIGHEST_SEQUENCE_NUMBER 0xEFFFFF00
99 /* ChunkCache is used for short read/write operations.*/
101 struct yaffs_ObjectStruct *object;
105 int nBytes; /* Only valid if the cache is dirty */
106 int locked; /* Can't push out or flush while locked. */
107 #ifdef CONFIG_YAFFS_YAFFS2
110 __u8 data[YAFFS_BYTES_PER_CHUNK];
116 /* Tags structures in RAM
117 * NB This uses bitfield. Bitfields should not straddle a u32 boundary otherwise
118 * the structure size will get blown out.
121 #ifndef CONFIG_YAFFS_NO_YAFFS1
124 unsigned serialNumber:2;
125 unsigned byteCount:10;
126 unsigned objectId:18;
128 unsigned unusedStuff:2;
139 /* Stuff used for extended tags in YAFFS2 */
142 YAFFS_ECC_RESULT_UNKNOWN,
143 YAFFS_ECC_RESULT_NO_ERROR,
144 YAFFS_ECC_RESULT_FIXED,
145 YAFFS_ECC_RESULT_UNFIXED
149 YAFFS_OBJECT_TYPE_UNKNOWN,
150 YAFFS_OBJECT_TYPE_FILE,
151 YAFFS_OBJECT_TYPE_SYMLINK,
152 YAFFS_OBJECT_TYPE_DIRECTORY,
153 YAFFS_OBJECT_TYPE_HARDLINK,
154 YAFFS_OBJECT_TYPE_SPECIAL
159 unsigned validMarker0;
160 unsigned chunkUsed; /* Status of the chunk: used or unused */
161 unsigned objectId; /* If 0 then this is not part of an object (unused) */
162 unsigned chunkId; /* If 0 then this is a header, else a data chunk */
163 unsigned byteCount; /* Only valid for data chunks */
165 /* The following stuff only has meaning when we read */
166 yaffs_ECCResult eccResult;
170 unsigned chunkDeleted; /* The chunk is marked deleted */
171 unsigned serialNumber; /* Yaffs1 2-bit serial number */
174 unsigned sequenceNumber; /* The sequence number of this block */
176 /* Extra info if this is an object header (YAFFS2 only) */
178 unsigned extraHeaderInfoAvailable; /* There is extra info available if this is not zero */
179 unsigned extraParentObjectId; /* The parent object */
180 unsigned extraIsShrinkHeader; /* Is it a shrink header? */
181 unsigned extraShadows; /* Does this shadow another object? */
183 yaffs_ObjectType extraObjectType; /* What object type? */
185 unsigned extraFileLength; /* Length if it is a file */
186 unsigned extraEquivalentObjectId; /* Equivalent object Id if it is a hard link */
188 unsigned validMarker1;
190 } yaffs_ExtendedTags;
192 /* Spare structure for YAFFS1 */
198 __u8 pageStatus; /* set to 0 to delete the chunk */
208 /*Special structure for passing through to mtd */
209 struct yaffs_NANDSpare {
215 /* Block data in RAM */
218 YAFFS_BLOCK_STATE_UNKNOWN = 0,
220 YAFFS_BLOCK_STATE_SCANNING,
221 YAFFS_BLOCK_STATE_NEEDS_SCANNING,
222 /* The block might have something on it (ie it is allocating or full, perhaps empty)
223 * but it needs to be scanned to determine its true state.
224 * This state is only valid during yaffs_Scan.
225 * NB We tolerate empty because the pre-scanner might be incapable of deciding
226 * However, if this state is returned on a YAFFS2 device, then we expect a sequence number
229 YAFFS_BLOCK_STATE_EMPTY,
230 /* This block is empty */
232 YAFFS_BLOCK_STATE_ALLOCATING,
233 /* This block is partially allocated.
234 * This is the one currently being used for page
235 * allocation. Should never be more than one of these
238 YAFFS_BLOCK_STATE_FULL,
239 /* All the pages in this block have been allocated.
240 * At least one page holds valid data.
243 YAFFS_BLOCK_STATE_DIRTY,
244 /* All pages have been allocated and deleted.
245 * Erase me, reuse me.
248 YAFFS_BLOCK_STATE_COLLECTING,
249 /* This block is being garbage collected */
251 YAFFS_BLOCK_STATE_DEAD
252 /* This block has failed and is not in use */
257 int softDeletions:12; /* number of soft deleted pages */
258 int pagesInUse:12; /* number of pages in use */
259 yaffs_BlockState blockState:4; /* One of the above block states */
260 __u32 needsRetiring:1; /* Data has failed on this block, need to get valid data off */
261 /* and retire the block. */
262 #ifdef CONFIG_YAFFS_YAFFS2
263 __u32 hasShrinkHeader:1; /* This block has at least one shrink object header */
264 __u32 sequenceNumber; /* block sequence number for yaffs2 */
269 /* -------------------------- Object structure -------------------------------*/
270 /* This is the object structure as stored on NAND */
273 yaffs_ObjectType type;
275 /* Apply to everything */
277 __u16 sum__NoLongerUsed; /* checksum of name. No longer used */
278 YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
280 /* Thes following apply to directories, files, symlinks - not hard links */
281 __u32 yst_mode; /* protection */
283 #ifdef CONFIG_YAFFS_WINCE
284 __u32 notForWinCE[5];
293 /* File size applies to files only */
296 /* Equivalent object id applies to hard links only. */
297 int equivalentObjectId;
299 /* Alias is for symlinks only. */
300 YCHAR alias[YAFFS_MAX_ALIAS_LENGTH + 1];
302 __u32 yst_rdev; /* device stuff for block and char devices (major/min) */
304 #ifdef CONFIG_YAFFS_WINCE
310 __u32 roomToGrow[10];
313 int shadowsObject; /* This object header shadows the specified object if > 0 */
315 /* isShrink applies to object headers written when we shrink the file (ie resize) */
318 } yaffs_ObjectHeader;
320 /*--------------------------- Tnode -------------------------- */
322 union yaffs_Tnode_union {
323 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
324 union yaffs_Tnode_union *internal[YAFFS_NTNODES_INTERNAL + 1];
326 union yaffs_Tnode_union *internal[YAFFS_NTNODES_INTERNAL];
328 /* __u16 level0[YAFFS_NTNODES_LEVEL0]; */
332 typedef union yaffs_Tnode_union yaffs_Tnode;
334 struct yaffs_TnodeList_struct {
335 struct yaffs_TnodeList_struct *next;
339 typedef struct yaffs_TnodeList_struct yaffs_TnodeList;
341 /*------------------------ Object -----------------------------*/
342 /* An object can be one of:
343 * - a directory (no data, has children links
344 * - a regular file (data.... not prunes :->).
345 * - a symlink [symbolic link] (the alias).
351 __u32 scannedFileSize;
355 } yaffs_FileStructure;
358 struct list_head children; /* list of child links */
359 } yaffs_DirectoryStructure;
363 } yaffs_SymLinkStructure;
366 struct yaffs_ObjectStruct *equivalentObject;
367 __u32 equivalentObjectId;
368 } yaffs_HardLinkStructure;
371 yaffs_FileStructure fileVariant;
372 yaffs_DirectoryStructure directoryVariant;
373 yaffs_SymLinkStructure symLinkVariant;
374 yaffs_HardLinkStructure hardLinkVariant;
375 } yaffs_ObjectVariant;
377 struct yaffs_ObjectStruct {
378 __u8 deleted:1; /* This should only apply to unlinked files. */
379 __u8 softDeleted:1; /* it has also been soft deleted */
380 __u8 unlinked:1; /* An unlinked file. The file should be in the unlinked directory.*/
381 __u8 fake:1; /* A fake object has no presence on NAND. */
382 __u8 renameAllowed:1; /* Some objects are not allowed to be renamed. */
383 __u8 unlinkAllowed:1;
384 __u8 dirty:1; /* the object needs to be written to flash */
385 __u8 valid:1; /* When the file system is being loaded up, this
386 * object might be created before the data
387 * is available (ie. file data records appear before the header).
389 __u8 serial; /* serial number of chunk in NAND. Cached here */
391 __u8 deferedFree:1; /* For Linux kernel. Object is removed from NAND, but is
392 * still in the inode cache. Free of object is defered.
393 * until the inode is released.
396 __u16 sum; /* sum of the name to speed searching */
398 struct yaffs_DeviceStruct *myDev; /* The device I'm on */
400 struct list_head hashLink; /* list of objects in this hash bucket */
402 struct list_head hardLinks; /* all the equivalent hard linked objects */
404 /* directory structure stuff */
405 /* also used for linking up the free list */
406 struct yaffs_ObjectStruct *parent;
407 struct list_head siblings;
409 /* Where's my object header in NAND? */
412 int nDataChunks; /* Number of data chunks attached to the file. */
414 __u32 objectId; /* the object id value */
418 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
419 YCHAR shortName[YAFFS_SHORT_NAME_LENGTH + 1];
426 #ifdef CONFIG_YAFFS_WINCE
441 struct inode *myInode;
445 yaffs_ObjectType variantType;
447 yaffs_ObjectVariant variant;
451 typedef struct yaffs_ObjectStruct yaffs_Object;
453 struct yaffs_ObjectList_struct {
454 yaffs_Object *objects;
455 struct yaffs_ObjectList_struct *next;
458 typedef struct yaffs_ObjectList_struct yaffs_ObjectList;
461 struct list_head list;
463 } yaffs_ObjectBucket;
465 /*--------------------- Temporary buffers ----------------
467 * These are chunk-sized working buffers. Each device has a few
472 int line; /* track from whence this buffer was allocated */
476 /*----------------- Device ---------------------------------*/
478 struct yaffs_DeviceStruct {
479 struct list_head devList;
482 /* Entry parameters set up way early. Yaffs sets up the rest.*/
483 int nBytesPerChunk; /* Should be a power of 2 >= 512 */
484 int nChunksPerBlock; /* does not need to be a power of 2 */
485 int nBytesPerSpare; /* spare area size */
486 int startBlock; /* Start block we're allowed to use */
487 int endBlock; /* End block we're allowed to use */
488 int nReservedBlocks; /* We want this tuneable so that we can reduce */
489 /* reserved blocks on NOR and RAM. */
491 int nShortOpCaches; /* If <= 0, then short op caching is disabled, else
492 * the number of short op caches (don't use too many)
495 int useHeaderFileSize; /* Flag to determine if we should use file sizes from the header */
497 int useNANDECC; /* Flag to decide whether or not to use NANDECC */
499 void *genericDevice; /* Pointer to device context
500 * On an mtd this holds the mtd pointer.
502 /* NAND access functions (Must be set before calling YAFFS)*/
504 int (*writeChunkToNAND) (struct yaffs_DeviceStruct * dev,
505 int chunkInNAND, const __u8 * data,
506 const yaffs_Spare * spare);
507 int (*readChunkFromNAND) (struct yaffs_DeviceStruct * dev,
508 int chunkInNAND, __u8 * data,
509 yaffs_Spare * spare);
510 int (*eraseBlockInNAND) (struct yaffs_DeviceStruct * dev,
512 int (*initialiseNAND) (struct yaffs_DeviceStruct * dev);
514 #ifdef CONFIG_YAFFS_YAFFS2
515 int (*writeChunkWithTagsToNAND) (struct yaffs_DeviceStruct * dev,
516 int chunkInNAND, const __u8 * data,
517 const yaffs_ExtendedTags * tags);
518 int (*readChunkWithTagsFromNAND) (struct yaffs_DeviceStruct * dev,
519 int chunkInNAND, __u8 * data,
520 yaffs_ExtendedTags * tags);
521 int (*markNANDBlockBad) (struct yaffs_DeviceStruct * dev, int blockNo);
522 int (*queryNANDBlock) (struct yaffs_DeviceStruct * dev, int blockNo,
523 yaffs_BlockState * state, int *sequenceNumber);
528 /* The removeObjectCallback function must be supplied by OS flavours that
529 * need it. The Linux kernel does not use this, but yaffs direct does use
530 * it to implement the faster readdir
532 void (*removeObjectCallback)(struct yaffs_ObjectStruct *obj);
534 int wideTnodesDisabled; /* Set to disable wide tnodes */
537 /* End of stuff that must be set before initialisation. */
539 /* Runtime parameters. Set up by YAFFS. */
541 __u16 chunkGroupBits; /* 0 for devices <= 32MB. else log2(nchunks) - 16 */
542 __u16 chunkGroupSize; /* == 2^^chunkGroupBits */
544 /* Stuff to support wide tnodes */
551 struct semaphore sem; /* Semaphore for waiting on erasure.*/
552 struct semaphore grossLock; /* Gross locking semaphore */
553 __u8 *spareBuffer; /* For mtdif2 use. Don't know the size of the buffer
554 * at compile time so we have to allocate it.
556 void (*putSuperFunc) (struct super_block * sb);
561 /* Stuff to support block offsetting to support start block zero */
562 int internalStartBlock;
563 int internalEndBlock;
568 yaffs_BlockInfo *blockInfo;
569 __u8 *chunkBits; /* bitmap of chunks in use */
570 unsigned blockInfoAlt:1; /* was allocated using alternative strategy */
571 unsigned chunkBitsAlt:1; /* was allocated using alternative strategy */
572 int chunkBitmapStride; /* Number of bytes of chunkBits per block.
573 * Must be consistent with nChunksPerBlock.
577 int allocationBlock; /* Current block being allocated off */
578 __u32 allocationPage;
579 int allocationBlockFinder; /* Used to search for next allocation block */
583 yaffs_Tnode *freeTnodes;
585 yaffs_TnodeList *allocatedTnodeList;
590 yaffs_Object *freeObjects;
593 yaffs_ObjectList *allocatedObjectList;
595 yaffs_ObjectBucket objectBucket[YAFFS_NOBJECT_BUCKETS];
599 int currentDirtyChecker; /* Used to find current dirtiest block */
601 __u32 *gcCleanupList; /* objects to delete at the end of a GC. */
607 int nErasureFailures;
609 int garbageCollections;
610 int passiveGarbageCollections;
618 int nUnmarkedDeletions;
620 /* Special directories */
621 yaffs_Object *rootDir;
622 yaffs_Object *lostNFoundDir;
624 /* Buffer areas for storing data to recover from write failures TODO
625 * __u8 bufferedData[YAFFS_CHUNKS_PER_BLOCK][YAFFS_BYTES_PER_CHUNK];
626 * yaffs_Spare bufferedSpare[YAFFS_CHUNKS_PER_BLOCK];
629 int bufferedBlock; /* Which block is buffered here? */
630 int doingBufferedBlockRewrite;
632 yaffs_ChunkCache *srCache;
637 /* Stuff for background deletion and unlinked files.*/
638 yaffs_Object *unlinkedDir; /* Directory where unlinked and deleted files live. */
639 yaffs_Object *deletedDir; /* Directory where deleted objects are sent to disappear. */
640 yaffs_Object *unlinkedDeletion; /* Current file being background deleted.*/
641 int nDeletedFiles; /* Count of files awaiting deletion;*/
642 int nUnlinkedFiles; /* Count of unlinked files. */
643 int nBackgroundDeletions; /* Count of background deletions. */
646 yaffs_TempBuffer tempBuffer[YAFFS_N_TEMP_BUFFERS];
648 int unmanagedTempAllocations;
649 int unmanagedTempDeallocations;
651 /* yaffs2 runtime stuff */
652 unsigned sequenceNumber; /* Sequence number of currently allocating block */
653 unsigned oldestDirtySequence;
657 typedef struct yaffs_DeviceStruct yaffs_Device;
659 /* Function to manipulate block info */
660 static Y_INLINE yaffs_BlockInfo *yaffs_GetBlockInfo(yaffs_Device * dev, int blk)
662 if (blk < dev->internalStartBlock || blk > dev->internalEndBlock) {
665 ("**>> yaffs: getBlockInfo block %d is not valid" TENDSTR),
669 return &dev->blockInfo[blk - dev->internalStartBlock];
672 /*----------------------- YAFFS Functions -----------------------*/
674 int yaffs_GutsInitialise(yaffs_Device * dev);
675 void yaffs_Deinitialise(yaffs_Device * dev);
677 int yaffs_GetNumberOfFreeChunks(yaffs_Device * dev);
679 int yaffs_RenameObject(yaffs_Object * oldDir, const YCHAR * oldName,
680 yaffs_Object * newDir, const YCHAR * newName);
682 int yaffs_Unlink(yaffs_Object * dir, const YCHAR * name);
683 int yaffs_DeleteFile(yaffs_Object * obj);
685 int yaffs_GetObjectName(yaffs_Object * obj, YCHAR * name, int buffSize);
686 int yaffs_GetObjectFileLength(yaffs_Object * obj);
687 int yaffs_GetObjectInode(yaffs_Object * obj);
688 unsigned yaffs_GetObjectType(yaffs_Object * obj);
689 int yaffs_GetObjectLinkCount(yaffs_Object * obj);
691 int yaffs_SetAttributes(yaffs_Object * obj, struct iattr *attr);
692 int yaffs_GetAttributes(yaffs_Object * obj, struct iattr *attr);
694 /* File operations */
695 int yaffs_ReadDataFromFile(yaffs_Object * obj, __u8 * buffer, __u32 offset,
697 int yaffs_WriteDataToFile(yaffs_Object * obj, const __u8 * buffer, __u32 offset,
698 int nBytes, int writeThrough);
699 int yaffs_ResizeFile(yaffs_Object * obj, int newSize);
701 yaffs_Object *yaffs_MknodFile(yaffs_Object * parent, const YCHAR * name,
702 __u32 mode, __u32 uid, __u32 gid);
703 int yaffs_FlushFile(yaffs_Object * obj, int updateTime);
705 /* Directory operations */
706 yaffs_Object *yaffs_MknodDirectory(yaffs_Object * parent, const YCHAR * name,
707 __u32 mode, __u32 uid, __u32 gid);
708 yaffs_Object *yaffs_FindObjectByName(yaffs_Object * theDir, const YCHAR * name);
709 int yaffs_ApplyToDirectoryChildren(yaffs_Object * theDir,
710 int (*fn) (yaffs_Object *));
712 yaffs_Object *yaffs_FindObjectByNumber(yaffs_Device * dev, __u32 number);
714 /* Link operations */
715 yaffs_Object *yaffs_Link(yaffs_Object * parent, const YCHAR * name,
716 yaffs_Object * equivalentObject);
718 yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object * obj);
720 /* Symlink operations */
721 yaffs_Object *yaffs_MknodSymLink(yaffs_Object * parent, const YCHAR * name,
722 __u32 mode, __u32 uid, __u32 gid,
723 const YCHAR * alias);
724 YCHAR *yaffs_GetSymlinkAlias(yaffs_Object * obj);
726 /* Special inodes (fifos, sockets and devices) */
727 yaffs_Object *yaffs_MknodSpecial(yaffs_Object * parent, const YCHAR * name,
728 __u32 mode, __u32 uid, __u32 gid, __u32 rdev);
730 /* Special directories */
731 yaffs_Object *yaffs_Root(yaffs_Device * dev);
732 yaffs_Object *yaffs_LostNFound(yaffs_Device * dev);
734 #ifdef CONFIG_YAFFS_WINCE
735 /* CONFIG_YAFFS_WINCE special stuff */
736 void yfsd_WinFileTimeNow(__u32 target[2]);
741 void yaffs_HandleDeferedFree(yaffs_Object * obj);
745 int yaffs_DumpObject(yaffs_Object * obj);
747 void yaffs_GutsTest(yaffs_Device * dev);
749 /* A few useful functions */
750 void yaffs_InitialiseTags(yaffs_ExtendedTags * tags);
751 void yaffs_DeleteChunk(yaffs_Device * dev, int chunkId, int markNAND, int lyn);
752 int yaffs_CheckFF(__u8 * buffer, int nBytes);