xref: /openbmc/u-boot/fs/yaffs2/yaffs_guts.h (revision 0e8cc8bd)
1 /*
2  * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
3  *
4  * Copyright (C) 2002-2007 Aleph One Ltd.
5  *   for Toby Churchill Ltd and Brightstar Engineering
6  *
7  * Created by Charles Manning <charles@aleph1.co.uk>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU Lesser General Public License version 2.1 as
11  * published by the Free Software Foundation.
12  *
13  * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
14  */
15 
16 #ifndef __YAFFS_GUTS_H__
17 #define __YAFFS_GUTS_H__
18 
19 #include "devextras.h"
20 #include "yportenv.h"
21 
22 #define YAFFS_OK	1
23 #define YAFFS_FAIL  0
24 
25 /* Give us a  Y=0x59,
26  * Give us an A=0x41,
27  * Give us an FF=0xFF
28  * Give us an S=0x53
29  * And what have we got...
30  */
31 #define YAFFS_MAGIC			0x5941FF53
32 
33 #define YAFFS_NTNODES_LEVEL0	  	16
34 #define YAFFS_TNODES_LEVEL0_BITS	4
35 #define YAFFS_TNODES_LEVEL0_MASK	0xf
36 
37 #define YAFFS_NTNODES_INTERNAL 		(YAFFS_NTNODES_LEVEL0 / 2)
38 #define YAFFS_TNODES_INTERNAL_BITS 	(YAFFS_TNODES_LEVEL0_BITS - 1)
39 #define YAFFS_TNODES_INTERNAL_MASK	0x7
40 #define YAFFS_TNODES_MAX_LEVEL		6
41 
42 #ifndef CONFIG_YAFFS_NO_YAFFS1
43 #define YAFFS_BYTES_PER_SPARE		16
44 #define YAFFS_BYTES_PER_CHUNK		512
45 #define YAFFS_CHUNK_SIZE_SHIFT		9
46 #define YAFFS_CHUNKS_PER_BLOCK		32
47 #define YAFFS_BYTES_PER_BLOCK		(YAFFS_CHUNKS_PER_BLOCK*YAFFS_BYTES_PER_CHUNK)
48 #endif
49 
50 #define YAFFS_MIN_YAFFS2_CHUNK_SIZE 	1024
51 #define YAFFS_MIN_YAFFS2_SPARE_SIZE	32
52 
53 #define YAFFS_MAX_CHUNK_ID		0x000FFFFF
54 
55 #define YAFFS_UNUSED_OBJECT_ID		0x0003FFFF
56 
57 #define YAFFS_ALLOCATION_NOBJECTS	100
58 #define YAFFS_ALLOCATION_NTNODES	100
59 #define YAFFS_ALLOCATION_NLINKS		100
60 
61 #define YAFFS_NOBJECT_BUCKETS		256
62 
63 
64 #define YAFFS_OBJECT_SPACE		0x40000
65 
66 #define YAFFS_CHECKPOINT_VERSION 	3
67 
68 #ifdef CONFIG_YAFFS_UNICODE
69 #define YAFFS_MAX_NAME_LENGTH		127
70 #define YAFFS_MAX_ALIAS_LENGTH		79
71 #else
72 #define YAFFS_MAX_NAME_LENGTH		255
73 #define YAFFS_MAX_ALIAS_LENGTH		159
74 #endif
75 
76 #define YAFFS_SHORT_NAME_LENGTH		15
77 
78 /* Some special object ids for pseudo objects */
79 #define YAFFS_OBJECTID_ROOT		1
80 #define YAFFS_OBJECTID_LOSTNFOUND	2
81 #define YAFFS_OBJECTID_UNLINKED		3
82 #define YAFFS_OBJECTID_DELETED		4
83 
84 /* Sseudo object ids for checkpointing */
85 #define YAFFS_OBJECTID_SB_HEADER	0x10
86 #define YAFFS_OBJECTID_CHECKPOINT_DATA	0x20
87 #define YAFFS_SEQUENCE_CHECKPOINT_DATA  0x21
88 
89 /* */
90 
91 #define YAFFS_MAX_SHORT_OP_CACHES	20
92 
93 #define YAFFS_N_TEMP_BUFFERS		4
94 
95 /* We limit the number attempts at sucessfully saving a chunk of data.
96  * Small-page devices have 32 pages per block; large-page devices have 64.
97  * Default to something in the order of 5 to 10 blocks worth of chunks.
98  */
99 #define YAFFS_WR_ATTEMPTS		(5*64)
100 
101 /* Sequence numbers are used in YAFFS2 to determine block allocation order.
102  * The range is limited slightly to help distinguish bad numbers from good.
103  * This also allows us to perhaps in the future use special numbers for
104  * special purposes.
105  * EFFFFF00 allows the allocation of 8 blocks per second (~1Mbytes) for 15 years,
106  * and is a larger number than the lifetime of a 2GB device.
107  */
108 #define YAFFS_LOWEST_SEQUENCE_NUMBER	0x00001000
109 #define YAFFS_HIGHEST_SEQUENCE_NUMBER	0xEFFFFF00
110 
111 /* ChunkCache is used for short read/write operations.*/
112 typedef struct {
113 	struct yaffs_ObjectStruct *object;
114 	int chunkId;
115 	int lastUse;
116 	int dirty;
117 	int nBytes;		/* Only valid if the cache is dirty */
118 	int locked;		/* Can't push out or flush while locked. */
119 #ifdef CONFIG_YAFFS_YAFFS2
120 	__u8 *data;
121 #else
122 	__u8 data[YAFFS_BYTES_PER_CHUNK];
123 #endif
124 } yaffs_ChunkCache;
125 
126 
127 
128 /* Tags structures in RAM
129  * NB This uses bitfield. Bitfields should not straddle a u32 boundary otherwise
130  * the structure size will get blown out.
131  */
132 
133 #ifndef CONFIG_YAFFS_NO_YAFFS1
134 typedef struct {
135 	unsigned chunkId:20;
136 	unsigned serialNumber:2;
137 	unsigned byteCount:10;
138 	unsigned objectId:18;
139 	unsigned ecc:12;
140 	unsigned unusedStuff:2;
141 
142 } yaffs_Tags;
143 
144 typedef union {
145 	yaffs_Tags asTags;
146 	__u8 asBytes[8];
147 } yaffs_TagsUnion;
148 
149 #endif
150 
151 /* Stuff used for extended tags in YAFFS2 */
152 
153 typedef enum {
154 	YAFFS_ECC_RESULT_UNKNOWN,
155 	YAFFS_ECC_RESULT_NO_ERROR,
156 	YAFFS_ECC_RESULT_FIXED,
157 	YAFFS_ECC_RESULT_UNFIXED
158 } yaffs_ECCResult;
159 
160 typedef enum {
161 	YAFFS_OBJECT_TYPE_UNKNOWN,
162 	YAFFS_OBJECT_TYPE_FILE,
163 	YAFFS_OBJECT_TYPE_SYMLINK,
164 	YAFFS_OBJECT_TYPE_DIRECTORY,
165 	YAFFS_OBJECT_TYPE_HARDLINK,
166 	YAFFS_OBJECT_TYPE_SPECIAL
167 } yaffs_ObjectType;
168 
169 #define YAFFS_OBJECT_TYPE_MAX YAFFS_OBJECT_TYPE_SPECIAL
170 
171 typedef struct {
172 
173 	unsigned validMarker0;
174 	unsigned chunkUsed;	/*  Status of the chunk: used or unused */
175 	unsigned objectId;	/* If 0 then this is not part of an object (unused) */
176 	unsigned chunkId;	/* If 0 then this is a header, else a data chunk */
177 	unsigned byteCount;	/* Only valid for data chunks */
178 
179 	/* The following stuff only has meaning when we read */
180 	yaffs_ECCResult eccResult;
181 	unsigned blockBad;
182 
183 	/* YAFFS 1 stuff */
184 	unsigned chunkDeleted;	/* The chunk is marked deleted */
185 	unsigned serialNumber;	/* Yaffs1 2-bit serial number */
186 
187 	/* YAFFS2 stuff */
188 	unsigned sequenceNumber;	/* The sequence number of this block */
189 
190 	/* Extra info if this is an object header (YAFFS2 only) */
191 
192 	unsigned extraHeaderInfoAvailable;	/* There is extra info available if this is not zero */
193 	unsigned extraParentObjectId;	/* The parent object */
194 	unsigned extraIsShrinkHeader;	/* Is it a shrink header? */
195 	unsigned extraShadows;		/* Does this shadow another object? */
196 
197 	yaffs_ObjectType extraObjectType;	/* What object type? */
198 
199 	unsigned extraFileLength;		/* Length if it is a file */
200 	unsigned extraEquivalentObjectId;	/* Equivalent object Id if it is a hard link */
201 
202 	unsigned validMarker1;
203 
204 } yaffs_ExtendedTags;
205 
206 /* Spare structure for YAFFS1 */
207 typedef struct {
208 	__u8 tagByte0;
209 	__u8 tagByte1;
210 	__u8 tagByte2;
211 	__u8 tagByte3;
212 	__u8 pageStatus;	/* set to 0 to delete the chunk */
213 	__u8 blockStatus;
214 	__u8 tagByte4;
215 	__u8 tagByte5;
216 	__u8 ecc1[3];
217 	__u8 tagByte6;
218 	__u8 tagByte7;
219 	__u8 ecc2[3];
220 } yaffs_Spare;
221 
222 /*Special structure for passing through to mtd */
223 struct yaffs_NANDSpare {
224 	yaffs_Spare spare;
225 	int eccres1;
226 	int eccres2;
227 };
228 
229 /* Block data in RAM */
230 
231 typedef enum {
232 	YAFFS_BLOCK_STATE_UNKNOWN = 0,
233 
234 	YAFFS_BLOCK_STATE_SCANNING,
235 	YAFFS_BLOCK_STATE_NEEDS_SCANNING,
236 	/* The block might have something on it (ie it is allocating or full, perhaps empty)
237 	 * but it needs to be scanned to determine its true state.
238 	 * This state is only valid during yaffs_Scan.
239 	 * NB We tolerate empty because the pre-scanner might be incapable of deciding
240 	 * However, if this state is returned on a YAFFS2 device, then we expect a sequence number
241 	 */
242 
243 	YAFFS_BLOCK_STATE_EMPTY,
244 	/* This block is empty */
245 
246 	YAFFS_BLOCK_STATE_ALLOCATING,
247 	/* This block is partially allocated.
248 	 * At least one page holds valid data.
249 	 * This is the one currently being used for page
250 	 * allocation. Should never be more than one of these
251 	 */
252 
253 	YAFFS_BLOCK_STATE_FULL,
254 	/* All the pages in this block have been allocated.
255 	 */
256 
257 	YAFFS_BLOCK_STATE_DIRTY,
258 	/* All pages have been allocated and deleted.
259 	 * Erase me, reuse me.
260 	 */
261 
262 	YAFFS_BLOCK_STATE_CHECKPOINT,
263 	/* This block is assigned to holding checkpoint data.
264 	 */
265 
266 	YAFFS_BLOCK_STATE_COLLECTING,
267 	/* This block is being garbage collected */
268 
269 	YAFFS_BLOCK_STATE_DEAD
270 	/* This block has failed and is not in use */
271 } yaffs_BlockState;
272 
273 #define	YAFFS_NUMBER_OF_BLOCK_STATES (YAFFS_BLOCK_STATE_DEAD + 1)
274 
275 
276 typedef struct {
277 
278 	int softDeletions:10;	/* number of soft deleted pages */
279 	int pagesInUse:10;	/* number of pages in use */
280 	unsigned blockState:4;	/* One of the above block states. NB use unsigned because enum is sometimes an int */
281 	__u32 needsRetiring:1;	/* Data has failed on this block, need to get valid data off */
282                         	/* and retire the block. */
283 	__u32 skipErasedCheck: 1; /* If this is set we can skip the erased check on this block */
284 	__u32 gcPrioritise: 1; 	/* An ECC check or blank check has failed on this block.
285 				   It should be prioritised for GC */
286         __u32 chunkErrorStrikes:3; /* How many times we've had ecc etc failures on this block and tried to reuse it */
287 
288 #ifdef CONFIG_YAFFS_YAFFS2
289 	__u32 hasShrinkHeader:1; /* This block has at least one shrink object header */
290 	__u32 sequenceNumber;	 /* block sequence number for yaffs2 */
291 #endif
292 
293 } yaffs_BlockInfo;
294 
295 /* -------------------------- Object structure -------------------------------*/
296 /* This is the object structure as stored on NAND */
297 
298 typedef struct {
299 	yaffs_ObjectType type;
300 
301 	/* Apply to everything  */
302 	int parentObjectId;
303 	__u16 sum__NoLongerUsed;	/* checksum of name. No longer used */
304 	YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
305 
306 	/* Thes following apply to directories, files, symlinks - not hard links */
307 	__u32 yst_mode;		/* protection */
308 
309 #ifdef CONFIG_YAFFS_WINCE
310 	__u32 notForWinCE[5];
311 #else
312 	__u32 yst_uid;
313 	__u32 yst_gid;
314 	__u32 yst_atime;
315 	__u32 yst_mtime;
316 	__u32 yst_ctime;
317 #endif
318 
319 	/* File size  applies to files only */
320 	int fileSize;
321 
322 	/* Equivalent object id applies to hard links only. */
323 	int equivalentObjectId;
324 
325 	/* Alias is for symlinks only. */
326 	YCHAR alias[YAFFS_MAX_ALIAS_LENGTH + 1];
327 
328 	__u32 yst_rdev;		/* device stuff for block and char devices (major/min) */
329 
330 #ifdef CONFIG_YAFFS_WINCE
331 	__u32 win_ctime[2];
332 	__u32 win_atime[2];
333 	__u32 win_mtime[2];
334 	__u32 roomToGrow[4];
335 #else
336 	__u32 roomToGrow[10];
337 #endif
338 
339 	int shadowsObject;	/* This object header shadows the specified object if > 0 */
340 
341 	/* isShrink applies to object headers written when we shrink the file (ie resize) */
342 	__u32 isShrink;
343 
344 } yaffs_ObjectHeader;
345 
346 /*--------------------------- Tnode -------------------------- */
347 
348 union yaffs_Tnode_union {
349 #ifdef CONFIG_YAFFS_TNODE_LIST_DEBUG
350 	union yaffs_Tnode_union *internal[YAFFS_NTNODES_INTERNAL + 1];
351 #else
352 	union yaffs_Tnode_union *internal[YAFFS_NTNODES_INTERNAL];
353 #endif
354 /*	__u16 level0[YAFFS_NTNODES_LEVEL0]; */
355 
356 };
357 
358 typedef union yaffs_Tnode_union yaffs_Tnode;
359 
360 struct yaffs_TnodeList_struct {
361 	struct yaffs_TnodeList_struct *next;
362 	yaffs_Tnode *tnodes;
363 };
364 
365 typedef struct yaffs_TnodeList_struct yaffs_TnodeList;
366 
367 /*------------------------  Object -----------------------------*/
368 /* An object can be one of:
369  * - a directory (no data, has children links
370  * - a regular file (data.... not prunes :->).
371  * - a symlink [symbolic link] (the alias).
372  * - a hard link
373  */
374 
375 typedef struct {
376 	__u32 fileSize;
377 	__u32 scannedFileSize;
378 	__u32 shrinkSize;
379 	int topLevel;
380 	yaffs_Tnode *top;
381 } yaffs_FileStructure;
382 
383 typedef struct {
384 	struct list_head children;	/* list of child links */
385 } yaffs_DirectoryStructure;
386 
387 typedef struct {
388 	YCHAR *alias;
389 } yaffs_SymLinkStructure;
390 
391 typedef struct {
392 	struct yaffs_ObjectStruct *equivalentObject;
393 	__u32 equivalentObjectId;
394 } yaffs_HardLinkStructure;
395 
396 typedef union {
397 	yaffs_FileStructure fileVariant;
398 	yaffs_DirectoryStructure directoryVariant;
399 	yaffs_SymLinkStructure symLinkVariant;
400 	yaffs_HardLinkStructure hardLinkVariant;
401 } yaffs_ObjectVariant;
402 
403 struct yaffs_ObjectStruct {
404 	__u8 deleted:1;		/* This should only apply to unlinked files. */
405 	__u8 softDeleted:1;	/* it has also been soft deleted */
406 	__u8 unlinked:1;	/* An unlinked file. The file should be in the unlinked directory.*/
407 	__u8 fake:1;		/* A fake object has no presence on NAND. */
408 	__u8 renameAllowed:1;	/* Some objects are not allowed to be renamed. */
409 	__u8 unlinkAllowed:1;
410 	__u8 dirty:1;		/* the object needs to be written to flash */
411 	__u8 valid:1;		/* When the file system is being loaded up, this
412 				 * object might be created before the data
413 				 * is available (ie. file data records appear before the header).
414 				 */
415 	__u8 lazyLoaded:1;	/* This object has been lazy loaded and is missing some detail */
416 
417 	__u8 deferedFree:1;	/* For Linux kernel. Object is removed from NAND, but is
418 				 * still in the inode cache. Free of object is defered.
419 				 * until the inode is released.
420 				 */
421 
422 	__u8 serial;		/* serial number of chunk in NAND. Cached here */
423 	__u16 sum;		/* sum of the name to speed searching */
424 
425 	struct yaffs_DeviceStruct *myDev;	/* The device I'm on */
426 
427 	struct list_head hashLink;	/* list of objects in this hash bucket */
428 
429 	struct list_head hardLinks;	/* all the equivalent hard linked objects */
430 
431 	/* directory structure stuff */
432 	/* also used for linking up the free list */
433 	struct yaffs_ObjectStruct *parent;
434 	struct list_head siblings;
435 
436 	/* Where's my object header in NAND? */
437 	int chunkId;
438 
439 	int nDataChunks;	/* Number of data chunks attached to the file. */
440 
441 	__u32 objectId;		/* the object id value */
442 
443 	__u32 yst_mode;
444 
445 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
446 	YCHAR shortName[YAFFS_SHORT_NAME_LENGTH + 1];
447 #endif
448 
449 #ifndef __KERNEL__
450 	__u32 inUse;
451 #endif
452 
453 #ifdef CONFIG_YAFFS_WINCE
454 	__u32 win_ctime[2];
455 	__u32 win_mtime[2];
456 	__u32 win_atime[2];
457 #else
458 	__u32 yst_uid;
459 	__u32 yst_gid;
460 	__u32 yst_atime;
461 	__u32 yst_mtime;
462 	__u32 yst_ctime;
463 #endif
464 
465 	__u32 yst_rdev;
466 
467 #ifdef __KERNEL__
468 	struct inode *myInode;
469 
470 #endif
471 
472 	yaffs_ObjectType variantType;
473 
474 	yaffs_ObjectVariant variant;
475 
476 };
477 
478 typedef struct yaffs_ObjectStruct yaffs_Object;
479 
480 struct yaffs_ObjectList_struct {
481 	yaffs_Object *objects;
482 	struct yaffs_ObjectList_struct *next;
483 };
484 
485 typedef struct yaffs_ObjectList_struct yaffs_ObjectList;
486 
487 typedef struct {
488 	struct list_head list;
489 	int count;
490 } yaffs_ObjectBucket;
491 
492 
493 /* yaffs_CheckpointObject holds the definition of an object as dumped
494  * by checkpointing.
495  */
496 
497 typedef struct {
498         int structType;
499 	__u32 objectId;
500 	__u32 parentId;
501 	int chunkId;
502 
503 	yaffs_ObjectType variantType:3;
504 	__u8 deleted:1;
505 	__u8 softDeleted:1;
506 	__u8 unlinked:1;
507 	__u8 fake:1;
508 	__u8 renameAllowed:1;
509 	__u8 unlinkAllowed:1;
510 	__u8 serial;
511 
512 	int nDataChunks;
513 	__u32 fileSizeOrEquivalentObjectId;
514 
515 }yaffs_CheckpointObject;
516 
517 /*--------------------- Temporary buffers ----------------
518  *
519  * These are chunk-sized working buffers. Each device has a few
520  */
521 
522 typedef struct {
523 	__u8 *buffer;
524 	int line;	/* track from whence this buffer was allocated */
525 	int maxLine;
526 } yaffs_TempBuffer;
527 
528 /*----------------- Device ---------------------------------*/
529 
530 struct yaffs_DeviceStruct {
531 	struct list_head devList;
532 	const char *name;
533 
534 	/* Entry parameters set up way early. Yaffs sets up the rest.*/
535 	int nDataBytesPerChunk;	/* Should be a power of 2 >= 512 */
536 	int nChunksPerBlock;	/* does not need to be a power of 2 */
537 	int nBytesPerSpare;	/* spare area size */
538 	int startBlock;		/* Start block we're allowed to use */
539 	int endBlock;		/* End block we're allowed to use */
540 	int nReservedBlocks;	/* We want this tuneable so that we can reduce */
541 				/* reserved blocks on NOR and RAM. */
542 
543 
544 	/* Stuff used by the shared space checkpointing mechanism */
545 	/* If this value is zero, then this mechanism is disabled */
546 
547 	int nCheckpointReservedBlocks; /* Blocks to reserve for checkpoint data */
548 
549 
550 
551 
552 	int nShortOpCaches;	/* If <= 0, then short op caching is disabled, else
553 				 * the number of short op caches (don't use too many)
554 				 */
555 
556 	int useHeaderFileSize;	/* Flag to determine if we should use file sizes from the header */
557 
558 	int useNANDECC;		/* Flag to decide whether or not to use NANDECC */
559 
560 	void *genericDevice;	/* Pointer to device context
561 				 * On an mtd this holds the mtd pointer.
562 				 */
563         void *superBlock;
564 
565 	/* NAND access functions (Must be set before calling YAFFS)*/
566 
567 	int (*writeChunkToNAND) (struct yaffs_DeviceStruct * dev,
568 				 int chunkInNAND, const __u8 * data,
569 				 const yaffs_Spare * spare);
570 	int (*readChunkFromNAND) (struct yaffs_DeviceStruct * dev,
571 				  int chunkInNAND, __u8 * data,
572 				  yaffs_Spare * spare);
573 	int (*eraseBlockInNAND) (struct yaffs_DeviceStruct * dev,
574 				 int blockInNAND);
575 	int (*initialiseNAND) (struct yaffs_DeviceStruct * dev);
576 
577 #ifdef CONFIG_YAFFS_YAFFS2
578 	int (*writeChunkWithTagsToNAND) (struct yaffs_DeviceStruct * dev,
579 					 int chunkInNAND, const __u8 * data,
580 					 const yaffs_ExtendedTags * tags);
581 	int (*readChunkWithTagsFromNAND) (struct yaffs_DeviceStruct * dev,
582 					  int chunkInNAND, __u8 * data,
583 					  yaffs_ExtendedTags * tags);
584 	int (*markNANDBlockBad) (struct yaffs_DeviceStruct * dev, int blockNo);
585 	int (*queryNANDBlock) (struct yaffs_DeviceStruct * dev, int blockNo,
586 			       yaffs_BlockState * state, int *sequenceNumber);
587 #endif
588 
589 	int isYaffs2;
590 
591 	/* The removeObjectCallback function must be supplied by OS flavours that
592 	 * need it. The Linux kernel does not use this, but yaffs direct does use
593 	 * it to implement the faster readdir
594 	 */
595 	void (*removeObjectCallback)(struct yaffs_ObjectStruct *obj);
596 
597 	/* Callback to mark the superblock dirsty */
598 	void (*markSuperBlockDirty)(void * superblock);
599 
600 	int wideTnodesDisabled; /* Set to disable wide tnodes */
601 
602 
603 	/* End of stuff that must be set before initialisation. */
604 
605 	/* Checkpoint control. Can be set before or after initialisation */
606 	__u8 skipCheckpointRead;
607 	__u8 skipCheckpointWrite;
608 
609 	/* Runtime parameters. Set up by YAFFS. */
610 
611 	__u16 chunkGroupBits;	/* 0 for devices <= 32MB. else log2(nchunks) - 16 */
612 	__u16 chunkGroupSize;	/* == 2^^chunkGroupBits */
613 
614 	/* Stuff to support wide tnodes */
615 	__u32 tnodeWidth;
616 	__u32 tnodeMask;
617 
618 	/* Stuff to support various file offses to chunk/offset translations */
619 	/* "Crumbs" for nDataBytesPerChunk not being a power of 2 */
620 	__u32 crumbMask;
621 	__u32 crumbShift;
622 	__u32 crumbsPerChunk;
623 
624 	/* Straight shifting for nDataBytesPerChunk being a power of 2 */
625 	__u32 chunkShift;
626 	__u32 chunkMask;
627 
628 
629 #ifdef __KERNEL__
630 
631 	struct semaphore sem;	/* Semaphore for waiting on erasure.*/
632 	struct semaphore grossLock;	/* Gross locking semaphore */
633 	__u8 *spareBuffer;	/* For mtdif2 use. Don't know the size of the buffer
634 				 * at compile time so we have to allocate it.
635 				 */
636 	void (*putSuperFunc) (struct super_block * sb);
637 #endif
638 
639 	int isMounted;
640 
641 	int isCheckpointed;
642 
643 
644 	/* Stuff to support block offsetting to support start block zero */
645 	int internalStartBlock;
646 	int internalEndBlock;
647 	int blockOffset;
648 	int chunkOffset;
649 
650 
651 	/* Runtime checkpointing stuff */
652 	int checkpointPageSequence;   /* running sequence number of checkpoint pages */
653 	int checkpointByteCount;
654 	int checkpointByteOffset;
655 	__u8 *checkpointBuffer;
656 	int checkpointOpenForWrite;
657 	int blocksInCheckpoint;
658 	int checkpointCurrentChunk;
659 	int checkpointCurrentBlock;
660 	int checkpointNextBlock;
661 	int *checkpointBlockList;
662 	int checkpointMaxBlocks;
663 	__u32 checkpointSum;
664 	__u32 checkpointXor;
665 
666 	/* Block Info */
667 	yaffs_BlockInfo *blockInfo;
668 	__u8 *chunkBits;	/* bitmap of chunks in use */
669 	unsigned blockInfoAlt:1;	/* was allocated using alternative strategy */
670 	unsigned chunkBitsAlt:1;	/* was allocated using alternative strategy */
671 	int chunkBitmapStride;	/* Number of bytes of chunkBits per block.
672 				 * Must be consistent with nChunksPerBlock.
673 				 */
674 
675 	int nErasedBlocks;
676 	int allocationBlock;	/* Current block being allocated off */
677 	__u32 allocationPage;
678 	int allocationBlockFinder;	/* Used to search for next allocation block */
679 
680 	/* Runtime state */
681 	int nTnodesCreated;
682 	yaffs_Tnode *freeTnodes;
683 	int nFreeTnodes;
684 	yaffs_TnodeList *allocatedTnodeList;
685 
686 	int isDoingGC;
687 
688 	int nObjectsCreated;
689 	yaffs_Object *freeObjects;
690 	int nFreeObjects;
691 
692 	yaffs_ObjectList *allocatedObjectList;
693 
694 	yaffs_ObjectBucket objectBucket[YAFFS_NOBJECT_BUCKETS];
695 
696 	int nFreeChunks;
697 
698 	int currentDirtyChecker;	/* Used to find current dirtiest block */
699 
700 	__u32 *gcCleanupList;	/* objects to delete at the end of a GC. */
701 	int nonAggressiveSkip;	/* GC state/mode */
702 
703 	/* Statistcs */
704 	int nPageWrites;
705 	int nPageReads;
706 	int nBlockErasures;
707 	int nErasureFailures;
708 	int nGCCopies;
709 	int garbageCollections;
710 	int passiveGarbageCollections;
711 	int nRetriedWrites;
712 	int nRetiredBlocks;
713 	int eccFixed;
714 	int eccUnfixed;
715 	int tagsEccFixed;
716 	int tagsEccUnfixed;
717 	int nDeletions;
718 	int nUnmarkedDeletions;
719 
720 	int hasPendingPrioritisedGCs; /* We think this device might have pending prioritised gcs */
721 
722 	/* Special directories */
723 	yaffs_Object *rootDir;
724 	yaffs_Object *lostNFoundDir;
725 
726 	/* Buffer areas for storing data to recover from write failures TODO
727 	 *      __u8            bufferedData[YAFFS_CHUNKS_PER_BLOCK][YAFFS_BYTES_PER_CHUNK];
728 	 *      yaffs_Spare bufferedSpare[YAFFS_CHUNKS_PER_BLOCK];
729 	 */
730 
731 	int bufferedBlock;	/* Which block is buffered here? */
732 	int doingBufferedBlockRewrite;
733 
734 	yaffs_ChunkCache *srCache;
735 	int srLastUse;
736 
737 	int cacheHits;
738 
739 	/* Stuff for background deletion and unlinked files.*/
740 	yaffs_Object *unlinkedDir;	/* Directory where unlinked and deleted files live. */
741 	yaffs_Object *deletedDir;	/* Directory where deleted objects are sent to disappear. */
742 	yaffs_Object *unlinkedDeletion;	/* Current file being background deleted.*/
743 	int nDeletedFiles;		/* Count of files awaiting deletion;*/
744 	int nUnlinkedFiles;		/* Count of unlinked files. */
745 	int nBackgroundDeletions;	/* Count of background deletions. */
746 
747 
748 	yaffs_TempBuffer tempBuffer[YAFFS_N_TEMP_BUFFERS];
749 	int maxTemp;
750 	int unmanagedTempAllocations;
751 	int unmanagedTempDeallocations;
752 
753 	/* yaffs2 runtime stuff */
754 	unsigned sequenceNumber;	/* Sequence number of currently allocating block */
755 	unsigned oldestDirtySequence;
756 
757 };
758 
759 typedef struct yaffs_DeviceStruct yaffs_Device;
760 
761 /* The static layout of bllock usage etc is stored in the super block header */
762 typedef struct {
763         int StructType;
764 	int version;
765 	int checkpointStartBlock;
766 	int checkpointEndBlock;
767 	int startBlock;
768 	int endBlock;
769 	int rfu[100];
770 } yaffs_SuperBlockHeader;
771 
772 /* The CheckpointDevice structure holds the device information that changes at runtime and
773  * must be preserved over unmount/mount cycles.
774  */
775 typedef struct {
776         int structType;
777 	int nErasedBlocks;
778 	int allocationBlock;	/* Current block being allocated off */
779 	__u32 allocationPage;
780 	int nFreeChunks;
781 
782 	int nDeletedFiles;		/* Count of files awaiting deletion;*/
783 	int nUnlinkedFiles;		/* Count of unlinked files. */
784 	int nBackgroundDeletions;	/* Count of background deletions. */
785 
786 	/* yaffs2 runtime stuff */
787 	unsigned sequenceNumber;	/* Sequence number of currently allocating block */
788 	unsigned oldestDirtySequence;
789 
790 } yaffs_CheckpointDevice;
791 
792 
793 typedef struct {
794     int structType;
795     __u32 magic;
796     __u32 version;
797     __u32 head;
798 } yaffs_CheckpointValidity;
799 
800 /* Function to manipulate block info */
801 static Y_INLINE yaffs_BlockInfo *yaffs_GetBlockInfo(yaffs_Device * dev, int blk)
802 {
803 	if (blk < dev->internalStartBlock || blk > dev->internalEndBlock) {
804 		T(YAFFS_TRACE_ERROR,
805 		  (TSTR
806 		   ("**>> yaffs: getBlockInfo block %d is not valid" TENDSTR),
807 		   blk));
808 		YBUG();
809 	}
810 	return &dev->blockInfo[blk - dev->internalStartBlock];
811 }
812 
813 /*----------------------- YAFFS Functions -----------------------*/
814 
815 int yaffs_GutsInitialise(yaffs_Device * dev);
816 void yaffs_Deinitialise(yaffs_Device * dev);
817 
818 int yaffs_GetNumberOfFreeChunks(yaffs_Device * dev);
819 
820 int yaffs_RenameObject(yaffs_Object * oldDir, const YCHAR * oldName,
821 		       yaffs_Object * newDir, const YCHAR * newName);
822 
823 int yaffs_Unlink(yaffs_Object * dir, const YCHAR * name);
824 int yaffs_DeleteFile(yaffs_Object * obj);
825 
826 int yaffs_GetObjectName(yaffs_Object * obj, YCHAR * name, int buffSize);
827 int yaffs_GetObjectFileLength(yaffs_Object * obj);
828 int yaffs_GetObjectInode(yaffs_Object * obj);
829 unsigned yaffs_GetObjectType(yaffs_Object * obj);
830 int yaffs_GetObjectLinkCount(yaffs_Object * obj);
831 
832 int yaffs_SetAttributes(yaffs_Object * obj, struct iattr *attr);
833 int yaffs_GetAttributes(yaffs_Object * obj, struct iattr *attr);
834 
835 /* File operations */
836 int yaffs_ReadDataFromFile(yaffs_Object * obj, __u8 * buffer, loff_t offset,
837 			   int nBytes);
838 int yaffs_WriteDataToFile(yaffs_Object * obj, const __u8 * buffer, loff_t offset,
839 			  int nBytes, int writeThrough);
840 int yaffs_ResizeFile(yaffs_Object * obj, loff_t newSize);
841 
842 yaffs_Object *yaffs_MknodFile(yaffs_Object * parent, const YCHAR * name,
843 			      __u32 mode, __u32 uid, __u32 gid);
844 int yaffs_FlushFile(yaffs_Object * obj, int updateTime);
845 
846 /* Flushing and checkpointing */
847 void yaffs_FlushEntireDeviceCache(yaffs_Device *dev);
848 
849 int yaffs_CheckpointSave(yaffs_Device *dev);
850 int yaffs_CheckpointRestore(yaffs_Device *dev);
851 
852 /* Directory operations */
853 yaffs_Object *yaffs_MknodDirectory(yaffs_Object * parent, const YCHAR * name,
854 				   __u32 mode, __u32 uid, __u32 gid);
855 yaffs_Object *yaffs_FindObjectByName(yaffs_Object * theDir, const YCHAR * name);
856 int yaffs_ApplyToDirectoryChildren(yaffs_Object * theDir,
857 				   int (*fn) (yaffs_Object *));
858 
859 yaffs_Object *yaffs_FindObjectByNumber(yaffs_Device * dev, __u32 number);
860 
861 /* Link operations */
862 yaffs_Object *yaffs_Link(yaffs_Object * parent, const YCHAR * name,
863 			 yaffs_Object * equivalentObject);
864 
865 yaffs_Object *yaffs_GetEquivalentObject(yaffs_Object * obj);
866 
867 /* Symlink operations */
868 yaffs_Object *yaffs_MknodSymLink(yaffs_Object * parent, const YCHAR * name,
869 				 __u32 mode, __u32 uid, __u32 gid,
870 				 const YCHAR * alias);
871 YCHAR *yaffs_GetSymlinkAlias(yaffs_Object * obj);
872 
873 /* Special inodes (fifos, sockets and devices) */
874 yaffs_Object *yaffs_MknodSpecial(yaffs_Object * parent, const YCHAR * name,
875 				 __u32 mode, __u32 uid, __u32 gid, __u32 rdev);
876 
877 /* Special directories */
878 yaffs_Object *yaffs_Root(yaffs_Device * dev);
879 yaffs_Object *yaffs_LostNFound(yaffs_Device * dev);
880 
881 #ifdef CONFIG_YAFFS_WINCE
882 /* CONFIG_YAFFS_WINCE special stuff */
883 void yfsd_WinFileTimeNow(__u32 target[2]);
884 #endif
885 
886 #ifdef __KERNEL__
887 
888 void yaffs_HandleDeferedFree(yaffs_Object * obj);
889 #endif
890 
891 /* Debug dump  */
892 int yaffs_DumpObject(yaffs_Object * obj);
893 
894 void yaffs_GutsTest(yaffs_Device * dev);
895 
896 /* A few useful functions */
897 void yaffs_InitialiseTags(yaffs_ExtendedTags * tags);
898 void yaffs_DeleteChunk(yaffs_Device * dev, int chunkId, int markNAND, int lyn);
899 int yaffs_CheckFF(__u8 * buffer, int nBytes);
900 void yaffs_HandleChunkError(yaffs_Device *dev, yaffs_BlockInfo *bi);
901 
902 #endif
903