1/*
2 * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
3 *
4 * Copyright (C) 2002-2011 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 "yportenv.h"
20
21#define YAFFS_OK	1
22#define YAFFS_FAIL  0
23
24/* Give us a  Y=0x59,
25 * Give us an A=0x41,
26 * Give us an FF=0xff
27 * Give us an S=0x53
28 * And what have we got...
29 */
30#define YAFFS_MAGIC			0x5941ff53
31
32/*
33 * Tnodes form a tree with the tnodes in "levels"
34 * Levels greater than 0 hold 8 slots which point to other tnodes.
35 * Those at level 0 hold 16 slots which point to chunks in NAND.
36 *
37 * A maximum level of 8 thust supports files of size up to:
38 *
39 * 2^(3*MAX_LEVEL+4)
40 *
41 * Thus a max level of 8 supports files with up to 2^^28 chunks which gives
42 * a maximum file size of around 512Gbytees with 2k chunks.
43 */
44#define YAFFS_NTNODES_LEVEL0		16
45#define YAFFS_TNODES_LEVEL0_BITS	4
46#define YAFFS_TNODES_LEVEL0_MASK	0xf
47
48#define YAFFS_NTNODES_INTERNAL		(YAFFS_NTNODES_LEVEL0 / 2)
49#define YAFFS_TNODES_INTERNAL_BITS	(YAFFS_TNODES_LEVEL0_BITS - 1)
50#define YAFFS_TNODES_INTERNAL_MASK	0x7
51#define YAFFS_TNODES_MAX_LEVEL		8
52#define YAFFS_TNODES_MAX_BITS		(YAFFS_TNODES_LEVEL0_BITS + \
53					YAFFS_TNODES_INTERNAL_BITS * \
54					YAFFS_TNODES_MAX_LEVEL)
55#define YAFFS_MAX_CHUNK_ID		((1 << YAFFS_TNODES_MAX_BITS) - 1)
56
57#define YAFFS_MAX_FILE_SIZE_32		0x7fffffff
58
59/* Constants for YAFFS1 mode */
60#define YAFFS_BYTES_PER_SPARE		16
61#define YAFFS_BYTES_PER_CHUNK		512
62#define YAFFS_CHUNK_SIZE_SHIFT		9
63#define YAFFS_CHUNKS_PER_BLOCK		32
64#define YAFFS_BYTES_PER_BLOCK	(YAFFS_CHUNKS_PER_BLOCK*YAFFS_BYTES_PER_CHUNK)
65
66#define YAFFS_MIN_YAFFS2_CHUNK_SIZE	1024
67#define YAFFS_MIN_YAFFS2_SPARE_SIZE	32
68
69
70
71#define YAFFS_ALLOCATION_NOBJECTS	100
72#define YAFFS_ALLOCATION_NTNODES	100
73#define YAFFS_ALLOCATION_NLINKS		100
74
75#define YAFFS_NOBJECT_BUCKETS		256
76
77#define YAFFS_OBJECT_SPACE		0x40000
78#define YAFFS_MAX_OBJECT_ID		(YAFFS_OBJECT_SPACE - 1)
79
80/* Binary data version stamps */
81#define YAFFS_SUMMARY_VERSION		1
82#define YAFFS_CHECKPOINT_VERSION	7
83
84#ifdef CONFIG_YAFFS_UNICODE
85#define YAFFS_MAX_NAME_LENGTH		127
86#define YAFFS_MAX_ALIAS_LENGTH		79
87#else
88#define YAFFS_MAX_NAME_LENGTH		255
89#define YAFFS_MAX_ALIAS_LENGTH		159
90#endif
91
92#define YAFFS_SHORT_NAME_LENGTH		15
93
94/* Some special object ids for pseudo objects */
95#define YAFFS_OBJECTID_ROOT		1
96#define YAFFS_OBJECTID_LOSTNFOUND	2
97#define YAFFS_OBJECTID_UNLINKED		3
98#define YAFFS_OBJECTID_DELETED		4
99
100/* Fake object Id for summary data */
101#define YAFFS_OBJECTID_SUMMARY		0x10
102
103/* Pseudo object ids for checkpointing */
104#define YAFFS_OBJECTID_CHECKPOINT_DATA	0x20
105#define YAFFS_SEQUENCE_CHECKPOINT_DATA	0x21
106
107#define YAFFS_MAX_SHORT_OP_CACHES	20
108
109#define YAFFS_N_TEMP_BUFFERS		6
110
111/* We limit the number attempts at sucessfully saving a chunk of data.
112 * Small-page devices have 32 pages per block; large-page devices have 64.
113 * Default to something in the order of 5 to 10 blocks worth of chunks.
114 */
115#define YAFFS_WR_ATTEMPTS		(5*64)
116
117/* Sequence numbers are used in YAFFS2 to determine block allocation order.
118 * The range is limited slightly to help distinguish bad numbers from good.
119 * This also allows us to perhaps in the future use special numbers for
120 * special purposes.
121 * EFFFFF00 allows the allocation of 8 blocks/second (~1Mbytes) for 15 years,
122 * and is a larger number than the lifetime of a 2GB device.
123 */
124#define YAFFS_LOWEST_SEQUENCE_NUMBER	0x00001000
125#define YAFFS_HIGHEST_SEQUENCE_NUMBER	0xefffff00
126
127/* Special sequence number for bad block that failed to be marked bad */
128#define YAFFS_SEQUENCE_BAD_BLOCK	0xffff0000
129
130/* ChunkCache is used for short read/write operations.*/
131struct yaffs_cache {
132	struct yaffs_obj *object;
133	int chunk_id;
134	int last_use;
135	int dirty;
136	int n_bytes;		/* Only valid if the cache is dirty */
137	int locked;		/* Can't push out or flush while locked. */
138	u8 *data;
139};
140
141/* yaffs1 tags structures in RAM
142 * NB This uses bitfield. Bitfields should not straddle a u32 boundary
143 * otherwise the structure size will get blown out.
144 */
145
146struct yaffs_tags {
147	u32 chunk_id:20;
148	u32 serial_number:2;
149	u32 n_bytes_lsb:10;
150	u32 obj_id:18;
151	u32 ecc:12;
152	u32 n_bytes_msb:2;
153};
154
155union yaffs_tags_union {
156	struct yaffs_tags as_tags;
157	u8 as_bytes[8];
158};
159
160
161/* Stuff used for extended tags in YAFFS2 */
162
163enum yaffs_ecc_result {
164	YAFFS_ECC_RESULT_UNKNOWN,
165	YAFFS_ECC_RESULT_NO_ERROR,
166	YAFFS_ECC_RESULT_FIXED,
167	YAFFS_ECC_RESULT_UNFIXED
168};
169
170enum yaffs_obj_type {
171	YAFFS_OBJECT_TYPE_UNKNOWN,
172	YAFFS_OBJECT_TYPE_FILE,
173	YAFFS_OBJECT_TYPE_SYMLINK,
174	YAFFS_OBJECT_TYPE_DIRECTORY,
175	YAFFS_OBJECT_TYPE_HARDLINK,
176	YAFFS_OBJECT_TYPE_SPECIAL
177};
178
179#define YAFFS_OBJECT_TYPE_MAX YAFFS_OBJECT_TYPE_SPECIAL
180
181struct yaffs_ext_tags {
182	unsigned chunk_used;	/*  Status of the chunk: used or unused */
183	unsigned obj_id;	/* If 0 this is not used */
184	unsigned chunk_id;	/* If 0 this is a header, else a data chunk */
185	unsigned n_bytes;	/* Only valid for data chunks */
186
187	/* The following stuff only has meaning when we read */
188	enum yaffs_ecc_result ecc_result;
189	unsigned block_bad;
190
191	/* YAFFS 1 stuff */
192	unsigned is_deleted;	/* The chunk is marked deleted */
193	unsigned serial_number;	/* Yaffs1 2-bit serial number */
194
195	/* YAFFS2 stuff */
196	unsigned seq_number;	/* The sequence number of this block */
197
198	/* Extra info if this is an object header (YAFFS2 only) */
199
200	unsigned extra_available;	/* Extra info available if not zero */
201	unsigned extra_parent_id;	/* The parent object */
202	unsigned extra_is_shrink;	/* Is it a shrink header? */
203	unsigned extra_shadows;	/* Does this shadow another object? */
204
205	enum yaffs_obj_type extra_obj_type;	/* What object type? */
206
207	loff_t extra_file_size;		/* Length if it is a file */
208	unsigned extra_equiv_id;	/* Equivalent object for a hard link */
209};
210
211/* Spare structure for YAFFS1 */
212struct yaffs_spare {
213	u8 tb0;
214	u8 tb1;
215	u8 tb2;
216	u8 tb3;
217	u8 page_status;		/* set to 0 to delete the chunk */
218	u8 block_status;
219	u8 tb4;
220	u8 tb5;
221	u8 ecc1[3];
222	u8 tb6;
223	u8 tb7;
224	u8 ecc2[3];
225};
226
227/*Special structure for passing through to mtd */
228struct yaffs_nand_spare {
229	struct yaffs_spare spare;
230	int eccres1;
231	int eccres2;
232};
233
234/* Block data in RAM */
235
236enum yaffs_block_state {
237	YAFFS_BLOCK_STATE_UNKNOWN = 0,
238
239	YAFFS_BLOCK_STATE_SCANNING,
240	/* Being scanned */
241
242	YAFFS_BLOCK_STATE_NEEDS_SCAN,
243	/* The block might have something on it (ie it is allocating or full,
244	 * perhaps empty) but it needs to be scanned to determine its true
245	 * state.
246	 * This state is only valid during scanning.
247	 * NB We tolerate empty because the pre-scanner might be incapable of
248	 * deciding
249	 * However, if this state is returned on a YAFFS2 device,
250	 * then we expect a sequence number
251	 */
252
253	YAFFS_BLOCK_STATE_EMPTY,
254	/* This block is empty */
255
256	YAFFS_BLOCK_STATE_ALLOCATING,
257	/* This block is partially allocated.
258	 * At least one page holds valid data.
259	 * This is the one currently being used for page
260	 * allocation. Should never be more than one of these.
261	 * If a block is only partially allocated at mount it is treated as
262	 * full.
263	 */
264
265	YAFFS_BLOCK_STATE_FULL,
266	/* All the pages in this block have been allocated.
267	 * If a block was only partially allocated when mounted we treat
268	 * it as fully allocated.
269	 */
270
271	YAFFS_BLOCK_STATE_DIRTY,
272	/* The block was full and now all chunks have been deleted.
273	 * Erase me, reuse me.
274	 */
275
276	YAFFS_BLOCK_STATE_CHECKPOINT,
277	/* This block is assigned to holding checkpoint data. */
278
279	YAFFS_BLOCK_STATE_COLLECTING,
280	/* This block is being garbage collected */
281
282	YAFFS_BLOCK_STATE_DEAD
283	    /* This block has failed and is not in use */
284};
285
286#define	YAFFS_NUMBER_OF_BLOCK_STATES (YAFFS_BLOCK_STATE_DEAD + 1)
287
288struct yaffs_block_info {
289
290	s32 soft_del_pages:10;	/* number of soft deleted pages */
291	s32 pages_in_use:10;	/* number of pages in use */
292	u32 block_state:4;	/* One of the above block states. */
293				/* NB use unsigned because enum is sometimes
294				 * an int */
295	u32 needs_retiring:1;	/* Data has failed on this block, */
296				/*need to get valid data off and retire*/
297	u32 skip_erased_check:1;/* Skip the erased check on this block */
298	u32 gc_prioritise:1;	/* An ECC check or blank check has failed.
299				   Block should be prioritised for GC */
300	u32 chunk_error_strikes:3;	/* How many times we've had ecc etc
301				failures on this block and tried to reuse it */
302	u32 has_summary:1;	/* The block has a summary */
303
304	u32 has_shrink_hdr:1;	/* This block has at least one shrink header */
305	u32 seq_number;		/* block sequence number for yaffs2 */
306
307};
308
309/* -------------------------- Object structure -------------------------------*/
310/* This is the object structure as stored on NAND */
311
312struct yaffs_obj_hdr {
313	enum yaffs_obj_type type;
314
315	/* Apply to everything  */
316	int parent_obj_id;
317	u16 sum_no_longer_used;	/* checksum of name. No longer used */
318	YCHAR name[YAFFS_MAX_NAME_LENGTH + 1];
319
320	/* The following apply to all object types except for hard links */
321	u32 yst_mode;		/* protection */
322
323	u32 yst_uid;
324	u32 yst_gid;
325	u32 yst_atime;
326	u32 yst_mtime;
327	u32 yst_ctime;
328
329	/* File size  applies to files only */
330	u32 file_size_low;
331
332	/* Equivalent object id applies to hard links only. */
333	int equiv_id;
334
335	/* Alias is for symlinks only. */
336	YCHAR alias[YAFFS_MAX_ALIAS_LENGTH + 1];
337
338	u32 yst_rdev;	/* stuff for block and char devices (major/min) */
339
340	u32 win_ctime[2];
341	u32 win_atime[2];
342	u32 win_mtime[2];
343
344	u32 inband_shadowed_obj_id;
345	u32 inband_is_shrink;
346
347	u32 file_size_high;
348	u32 reserved[1];
349	int shadows_obj;	/* This object header shadows the
350				specified object if > 0 */
351
352	/* is_shrink applies to object headers written when wemake a hole. */
353	u32 is_shrink;
354
355};
356
357/*--------------------------- Tnode -------------------------- */
358
359struct yaffs_tnode {
360	struct yaffs_tnode *internal[YAFFS_NTNODES_INTERNAL];
361};
362
363/*------------------------  Object -----------------------------*/
364/* An object can be one of:
365 * - a directory (no data, has children links
366 * - a regular file (data.... not prunes :->).
367 * - a symlink [symbolic link] (the alias).
368 * - a hard link
369 */
370
371struct yaffs_file_var {
372	loff_t file_size;
373	loff_t scanned_size;
374	loff_t shrink_size;
375	int top_level;
376	struct yaffs_tnode *top;
377};
378
379struct yaffs_dir_var {
380	struct list_head children;	/* list of child links */
381	struct list_head dirty;	/* Entry for list of dirty directories */
382};
383
384struct yaffs_symlink_var {
385	YCHAR *alias;
386};
387
388struct yaffs_hardlink_var {
389	struct yaffs_obj *equiv_obj;
390	u32 equiv_id;
391};
392
393union yaffs_obj_var {
394	struct yaffs_file_var file_variant;
395	struct yaffs_dir_var dir_variant;
396	struct yaffs_symlink_var symlink_variant;
397	struct yaffs_hardlink_var hardlink_variant;
398};
399
400struct yaffs_obj {
401	u8 deleted:1;		/* This should only apply to unlinked files. */
402	u8 soft_del:1;		/* it has also been soft deleted */
403	u8 unlinked:1;		/* An unlinked file.*/
404	u8 fake:1;		/* A fake object has no presence on NAND. */
405	u8 rename_allowed:1;	/* Some objects cannot be renamed. */
406	u8 unlink_allowed:1;
407	u8 dirty:1;		/* the object needs to be written to flash */
408	u8 valid:1;		/* When the file system is being loaded up, this
409				 * object might be created before the data
410				 * is available
411				 * ie. file data chunks encountered before
412				* the header.
413				 */
414	u8 lazy_loaded:1;	/* This object has been lazy loaded and
415				 * is missing some detail */
416
417	u8 defered_free:1;	/* Object is removed from NAND, but is
418				 * still in the inode cache.
419				 * Free of object is defered.
420				 * until the inode is released.
421				 */
422	u8 being_created:1;	/* This object is still being created
423				 * so skip some verification checks. */
424	u8 is_shadowed:1;	/* This object is shadowed on the way
425				 * to being renamed. */
426
427	u8 xattr_known:1;	/* We know if this has object has xattribs
428				 * or not. */
429	u8 has_xattr:1;		/* This object has xattribs.
430				 * Only valid if xattr_known. */
431
432	u8 serial;		/* serial number of chunk in NAND.*/
433	u16 sum;		/* sum of the name to speed searching */
434
435	struct yaffs_dev *my_dev;	/* The device I'm on */
436
437	struct list_head hash_link;	/* list of objects in hash bucket */
438
439	struct list_head hard_links;	/* hard linked object chain*/
440
441	/* directory structure stuff */
442	/* also used for linking up the free list */
443	struct yaffs_obj *parent;
444	struct list_head siblings;
445
446	/* Where's my object header in NAND? */
447	int hdr_chunk;
448
449	int n_data_chunks;	/* Number of data chunks for this file. */
450
451	u32 obj_id;		/* the object id value */
452
453	u32 yst_mode;
454
455	YCHAR short_name[YAFFS_SHORT_NAME_LENGTH + 1];
456
457#ifdef CONFIG_YAFFS_WINCE
458	u32 win_ctime[2];
459	u32 win_mtime[2];
460	u32 win_atime[2];
461#else
462	u32 yst_uid;
463	u32 yst_gid;
464	u32 yst_atime;
465	u32 yst_mtime;
466	u32 yst_ctime;
467#endif
468
469	u32 yst_rdev;
470
471	void *my_inode;
472
473	enum yaffs_obj_type variant_type;
474
475	union yaffs_obj_var variant;
476
477};
478
479struct yaffs_obj_bucket {
480	struct list_head list;
481	int count;
482};
483
484/* yaffs_checkpt_obj holds the definition of an object as dumped
485 * by checkpointing.
486 */
487
488struct yaffs_checkpt_obj {
489	int struct_type;
490	u32 obj_id;
491	u32 parent_id;
492	int hdr_chunk;
493	enum yaffs_obj_type variant_type:3;
494	u8 deleted:1;
495	u8 soft_del:1;
496	u8 unlinked:1;
497	u8 fake:1;
498	u8 rename_allowed:1;
499	u8 unlink_allowed:1;
500	u8 serial;
501	int n_data_chunks;
502	loff_t size_or_equiv_obj;
503};
504
505/*--------------------- Temporary buffers ----------------
506 *
507 * These are chunk-sized working buffers. Each device has a few.
508 */
509
510struct yaffs_buffer {
511	u8 *buffer;
512	int in_use;
513};
514
515/*----------------- Device ---------------------------------*/
516
517struct yaffs_param {
518	const YCHAR *name;
519
520	/*
521	 * Entry parameters set up way early. Yaffs sets up the rest.
522	 * The structure should be zeroed out before use so that unused
523	 * and default values are zero.
524	 */
525
526	int inband_tags;	/* Use unband tags */
527	u32 total_bytes_per_chunk;	/* Should be >= 512, does not need to
528					 be a power of 2 */
529	int chunks_per_block;	/* does not need to be a power of 2 */
530	int spare_bytes_per_chunk;	/* spare area size */
531	int start_block;	/* Start block we're allowed to use */
532	int end_block;		/* End block we're allowed to use */
533	int n_reserved_blocks;	/* Tuneable so that we can reduce
534				 * reserved blocks on NOR and RAM. */
535
536	int n_caches;		/* If <= 0, then short op caching is disabled,
537				 * else the number of short op caches.
538				 */
539	int cache_bypass_aligned; /* If non-zero then bypass the cache for
540				   * aligned writes.
541				   */
542
543	int use_nand_ecc;	/* Flag to decide whether or not to use
544				 * NAND driver ECC on data (yaffs1) */
545	int tags_9bytes;	/* Use 9 byte tags */
546	int no_tags_ecc;	/* Flag to decide whether or not to do ECC
547				 * on packed tags (yaffs2) */
548
549	int is_yaffs2;		/* Use yaffs2 mode on this device */
550
551	int empty_lost_n_found;	/* Auto-empty lost+found directory on mount */
552
553	int refresh_period;	/* How often to check for a block refresh */
554
555	/* Checkpoint control. Can be set before or after initialisation */
556	u8 skip_checkpt_rd;
557	u8 skip_checkpt_wr;
558
559	int enable_xattr;	/* Enable xattribs */
560
561	int max_objects;	/*
562				 * Set to limit the number of objects created.
563				 * 0 = no limit.
564				*/
565
566	/* The remove_obj_fn function must be supplied by OS flavours that
567	 * need it.
568	 * yaffs direct uses it to implement the faster readdir.
569	 * Linux uses it to protect the directory during unlocking.
570	 */
571	void (*remove_obj_fn) (struct yaffs_obj *obj);
572
573	/* Callback to mark the superblock dirty */
574	void (*sb_dirty_fn) (struct yaffs_dev *dev);
575
576	/*  Callback to control garbage collection. */
577	unsigned (*gc_control_fn) (struct yaffs_dev *dev);
578
579	/* Debug control flags. Don't use unless you know what you're doing */
580	int use_header_file_size;	/* Flag to determine if we should use
581					 * file sizes from the header */
582	int disable_lazy_load;	/* Disable lazy loading on this device */
583	int wide_tnodes_disabled;	/* Set to disable wide tnodes */
584	int disable_soft_del;	/* yaffs 1 only: Set to disable the use of
585				 * softdeletion. */
586
587	int defered_dir_update;	/* Set to defer directory updates */
588
589#ifdef CONFIG_YAFFS_AUTO_UNICODE
590	int auto_unicode;
591#endif
592	int always_check_erased;	/* Force chunk erased check always on */
593
594	int disable_summary;
595	int disable_bad_block_marking;
596
597};
598
599struct yaffs_driver {
600	int (*drv_write_chunk_fn) (struct yaffs_dev *dev, int nand_chunk,
601				   const u8 *data, int data_len,
602				   const u8 *oob, int oob_len);
603	int (*drv_read_chunk_fn) (struct yaffs_dev *dev, int nand_chunk,
604				   u8 *data, int data_len,
605				   u8 *oob, int oob_len,
606				   enum yaffs_ecc_result *ecc_result);
607	int (*drv_erase_fn) (struct yaffs_dev *dev, int block_no);
608	int (*drv_mark_bad_fn) (struct yaffs_dev *dev, int block_no);
609	int (*drv_check_bad_fn) (struct yaffs_dev *dev, int block_no);
610	int (*drv_initialise_fn) (struct yaffs_dev *dev);
611	int (*drv_deinitialise_fn) (struct yaffs_dev *dev);
612};
613
614struct yaffs_tags_handler {
615	int (*write_chunk_tags_fn) (struct yaffs_dev *dev,
616				    int nand_chunk, const u8 *data,
617				    const struct yaffs_ext_tags *tags);
618	int (*read_chunk_tags_fn) (struct yaffs_dev *dev,
619				   int nand_chunk, u8 *data,
620				   struct yaffs_ext_tags *tags);
621
622	int (*query_block_fn) (struct yaffs_dev *dev, int block_no,
623			       enum yaffs_block_state *state,
624			       u32 *seq_number);
625	int (*mark_bad_fn) (struct yaffs_dev *dev, int block_no);
626};
627
628struct yaffs_dev {
629	struct yaffs_param param;
630	struct yaffs_driver drv;
631	struct yaffs_tags_handler tagger;
632
633	/* Context storage. Holds extra OS specific data for this device */
634
635	void *os_context;
636	void *driver_context;
637
638	struct list_head dev_list;
639
640	int ll_init;
641	/* Runtime parameters. Set up by YAFFS. */
642	int data_bytes_per_chunk;
643
644	/* Non-wide tnode stuff */
645	u16 chunk_grp_bits;	/* Number of bits that need to be resolved if
646				 * the tnodes are not wide enough.
647				 */
648	u16 chunk_grp_size;	/* == 2^^chunk_grp_bits */
649
650	/* Stuff to support wide tnodes */
651	u32 tnode_width;
652	u32 tnode_mask;
653	u32 tnode_size;
654
655	/* Stuff for figuring out file offset to chunk conversions */
656	u32 chunk_shift;	/* Shift value */
657	u32 chunk_div;		/* Divisor after shifting: 1 for 2^n sizes */
658	u32 chunk_mask;		/* Mask to use for power-of-2 case */
659
660	int is_mounted;
661	int read_only;
662	int is_checkpointed;
663
664	/* Stuff to support block offsetting to support start block zero */
665	int internal_start_block;
666	int internal_end_block;
667	int block_offset;
668	int chunk_offset;
669
670	/* Runtime checkpointing stuff */
671	int checkpt_page_seq;	/* running sequence number of checkpt pages */
672	int checkpt_byte_count;
673	int checkpt_byte_offs;
674	u8 *checkpt_buffer;
675	int checkpt_open_write;
676	int blocks_in_checkpt;
677	int checkpt_cur_chunk;
678	int checkpt_cur_block;
679	int checkpt_next_block;
680	int *checkpt_block_list;
681	int checkpt_max_blocks;
682	u32 checkpt_sum;
683	u32 checkpt_xor;
684
685	int checkpoint_blocks_required;	/* Number of blocks needed to store
686					 * current checkpoint set */
687
688	/* Block Info */
689	struct yaffs_block_info *block_info;
690	u8 *chunk_bits;		/* bitmap of chunks in use */
691	u8 block_info_alt:1;	/* allocated using alternative alloc */
692	u8 chunk_bits_alt:1;	/* allocated using alternative alloc */
693	int chunk_bit_stride;	/* Number of bytes of chunk_bits per block.
694				 * Must be consistent with chunks_per_block.
695				 */
696
697	int n_erased_blocks;
698	int alloc_block;	/* Current block being allocated off */
699	u32 alloc_page;
700	int alloc_block_finder;	/* Used to search for next allocation block */
701
702	/* Object and Tnode memory management */
703	void *allocator;
704	int n_obj;
705	int n_tnodes;
706
707	int n_hardlinks;
708
709	struct yaffs_obj_bucket obj_bucket[YAFFS_NOBJECT_BUCKETS];
710	u32 bucket_finder;
711
712	int n_free_chunks;
713
714	/* Garbage collection control */
715	u32 *gc_cleanup_list;	/* objects to delete at the end of a GC. */
716	u32 n_clean_ups;
717
718	unsigned has_pending_prioritised_gc;	/* We think this device might
719						have pending prioritised gcs */
720	unsigned gc_disable;
721	unsigned gc_block_finder;
722	unsigned gc_dirtiest;
723	unsigned gc_pages_in_use;
724	unsigned gc_not_done;
725	unsigned gc_block;
726	unsigned gc_chunk;
727	unsigned gc_skip;
728	struct yaffs_summary_tags *gc_sum_tags;
729
730	/* Special directories */
731	struct yaffs_obj *root_dir;
732	struct yaffs_obj *lost_n_found;
733
734	int buffered_block;	/* Which block is buffered here? */
735	int doing_buffered_block_rewrite;
736
737	struct yaffs_cache *cache;
738	int cache_last_use;
739
740	/* Stuff for background deletion and unlinked files. */
741	struct yaffs_obj *unlinked_dir;	/* Directory where unlinked and deleted
742					 files live. */
743	struct yaffs_obj *del_dir;	/* Directory where deleted objects are
744					sent to disappear. */
745	struct yaffs_obj *unlinked_deletion;	/* Current file being
746							background deleted. */
747	int n_deleted_files;	/* Count of files awaiting deletion; */
748	int n_unlinked_files;	/* Count of unlinked files. */
749	int n_bg_deletions;	/* Count of background deletions. */
750
751	/* Temporary buffer management */
752	struct yaffs_buffer temp_buffer[YAFFS_N_TEMP_BUFFERS];
753	int max_temp;
754	int temp_in_use;
755	int unmanaged_buffer_allocs;
756	int unmanaged_buffer_deallocs;
757
758	/* yaffs2 runtime stuff */
759	unsigned seq_number;	/* Sequence number of currently
760					allocating block */
761	unsigned oldest_dirty_seq;
762	unsigned oldest_dirty_block;
763
764	/* Block refreshing */
765	int refresh_skip;	/* A skip down counter.
766				 * Refresh happens when this gets to zero. */
767
768	/* Dirty directory handling */
769	struct list_head dirty_dirs;	/* List of dirty directories */
770
771	/* Summary */
772	int chunks_per_summary;
773	struct yaffs_summary_tags *sum_tags;
774
775	/* Statistics */
776	u32 n_page_writes;
777	u32 n_page_reads;
778	u32 n_erasures;
779	u32 n_bad_queries;
780	u32 n_bad_markings;
781	u32 n_erase_failures;
782	u32 n_gc_copies;
783	u32 all_gcs;
784	u32 passive_gc_count;
785	u32 oldest_dirty_gc_count;
786	u32 n_gc_blocks;
787	u32 bg_gcs;
788	u32 n_retried_writes;
789	u32 n_retired_blocks;
790	u32 n_ecc_fixed;
791	u32 n_ecc_unfixed;
792	u32 n_tags_ecc_fixed;
793	u32 n_tags_ecc_unfixed;
794	u32 n_deletions;
795	u32 n_unmarked_deletions;
796	u32 refresh_count;
797	u32 cache_hits;
798	u32 tags_used;
799	u32 summary_used;
800
801};
802
803/* The CheckpointDevice structure holds the device information that changes
804 *at runtime and must be preserved over unmount/mount cycles.
805 */
806struct yaffs_checkpt_dev {
807	int struct_type;
808	int n_erased_blocks;
809	int alloc_block;	/* Current block being allocated off */
810	u32 alloc_page;
811	int n_free_chunks;
812
813	int n_deleted_files;	/* Count of files awaiting deletion; */
814	int n_unlinked_files;	/* Count of unlinked files. */
815	int n_bg_deletions;	/* Count of background deletions. */
816
817	/* yaffs2 runtime stuff */
818	unsigned seq_number;	/* Sequence number of currently
819				 * allocating block */
820
821};
822
823struct yaffs_checkpt_validity {
824	int struct_type;
825	u32 magic;
826	u32 version;
827	u32 head;
828};
829
830struct yaffs_shadow_fixer {
831	int obj_id;
832	int shadowed_id;
833	struct yaffs_shadow_fixer *next;
834};
835
836/* Structure for doing xattr modifications */
837struct yaffs_xattr_mod {
838	int set;		/* If 0 then this is a deletion */
839	const YCHAR *name;
840	const void *data;
841	int size;
842	int flags;
843	int result;
844};
845
846/*----------------------- YAFFS Functions -----------------------*/
847
848int yaffs_guts_initialise(struct yaffs_dev *dev);
849void yaffs_deinitialise(struct yaffs_dev *dev);
850
851int yaffs_get_n_free_chunks(struct yaffs_dev *dev);
852
853int yaffs_rename_obj(struct yaffs_obj *old_dir, const YCHAR * old_name,
854		     struct yaffs_obj *new_dir, const YCHAR * new_name);
855
856int yaffs_unlinker(struct yaffs_obj *dir, const YCHAR * name);
857int yaffs_del_obj(struct yaffs_obj *obj);
858struct yaffs_obj *yaffs_retype_obj(struct yaffs_obj *obj,
859				   enum yaffs_obj_type type);
860
861
862int yaffs_get_obj_name(struct yaffs_obj *obj, YCHAR * name, int buffer_size);
863loff_t yaffs_get_obj_length(struct yaffs_obj *obj);
864int yaffs_get_obj_inode(struct yaffs_obj *obj);
865unsigned yaffs_get_obj_type(struct yaffs_obj *obj);
866int yaffs_get_obj_link_count(struct yaffs_obj *obj);
867
868/* File operations */
869int yaffs_file_rd(struct yaffs_obj *obj, u8 * buffer, loff_t offset,
870		  int n_bytes);
871int yaffs_wr_file(struct yaffs_obj *obj, const u8 * buffer, loff_t offset,
872		  int n_bytes, int write_trhrough);
873int yaffs_resize_file(struct yaffs_obj *obj, loff_t new_size);
874
875struct yaffs_obj *yaffs_create_file(struct yaffs_obj *parent,
876				    const YCHAR *name, u32 mode, u32 uid,
877				    u32 gid);
878
879int yaffs_flush_file(struct yaffs_obj *in,
880		     int update_time,
881		     int data_sync,
882		     int discard_cache);
883
884/* Flushing and checkpointing */
885void yaffs_flush_whole_cache(struct yaffs_dev *dev, int discard);
886
887int yaffs_checkpoint_save(struct yaffs_dev *dev);
888int yaffs_checkpoint_restore(struct yaffs_dev *dev);
889
890/* Directory operations */
891struct yaffs_obj *yaffs_create_dir(struct yaffs_obj *parent, const YCHAR *name,
892				   u32 mode, u32 uid, u32 gid);
893struct yaffs_obj *yaffs_find_by_name(struct yaffs_obj *the_dir,
894				     const YCHAR *name);
895struct yaffs_obj *yaffs_find_by_number(struct yaffs_dev *dev, u32 number);
896
897/* Link operations */
898struct yaffs_obj *yaffs_link_obj(struct yaffs_obj *parent, const YCHAR *name,
899				 struct yaffs_obj *equiv_obj);
900
901struct yaffs_obj *yaffs_get_equivalent_obj(struct yaffs_obj *obj);
902
903/* Symlink operations */
904struct yaffs_obj *yaffs_create_symlink(struct yaffs_obj *parent,
905				       const YCHAR *name, u32 mode, u32 uid,
906				       u32 gid, const YCHAR *alias);
907YCHAR *yaffs_get_symlink_alias(struct yaffs_obj *obj);
908
909/* Special inodes (fifos, sockets and devices) */
910struct yaffs_obj *yaffs_create_special(struct yaffs_obj *parent,
911				       const YCHAR *name, u32 mode, u32 uid,
912				       u32 gid, u32 rdev);
913
914int yaffs_set_xattrib(struct yaffs_obj *obj, const YCHAR *name,
915		      const void *value, int size, int flags);
916int yaffs_get_xattrib(struct yaffs_obj *obj, const YCHAR *name, void *value,
917		      int size);
918int yaffs_list_xattrib(struct yaffs_obj *obj, char *buffer, int size);
919int yaffs_remove_xattrib(struct yaffs_obj *obj, const YCHAR *name);
920
921/* Special directories */
922struct yaffs_obj *yaffs_root(struct yaffs_dev *dev);
923struct yaffs_obj *yaffs_lost_n_found(struct yaffs_dev *dev);
924
925void yaffs_handle_defered_free(struct yaffs_obj *obj);
926
927void yaffs_update_dirty_dirs(struct yaffs_dev *dev);
928
929int yaffs_bg_gc(struct yaffs_dev *dev, unsigned urgency);
930
931/* Debug dump  */
932int yaffs_dump_obj(struct yaffs_obj *obj);
933
934void yaffs_guts_test(struct yaffs_dev *dev);
935int yaffs_guts_ll_init(struct yaffs_dev *dev);
936
937
938/* A few useful functions to be used within the core files*/
939void yaffs_chunk_del(struct yaffs_dev *dev, int chunk_id, int mark_flash,
940		     int lyn);
941int yaffs_check_ff(u8 *buffer, int n_bytes);
942void yaffs_handle_chunk_error(struct yaffs_dev *dev,
943			      struct yaffs_block_info *bi);
944
945u8 *yaffs_get_temp_buffer(struct yaffs_dev *dev);
946void yaffs_release_temp_buffer(struct yaffs_dev *dev, u8 *buffer);
947
948struct yaffs_obj *yaffs_find_or_create_by_number(struct yaffs_dev *dev,
949						 int number,
950						 enum yaffs_obj_type type);
951int yaffs_put_chunk_in_file(struct yaffs_obj *in, int inode_chunk,
952			    int nand_chunk, int in_scan);
953void yaffs_set_obj_name(struct yaffs_obj *obj, const YCHAR *name);
954void yaffs_set_obj_name_from_oh(struct yaffs_obj *obj,
955				const struct yaffs_obj_hdr *oh);
956void yaffs_add_obj_to_dir(struct yaffs_obj *directory, struct yaffs_obj *obj);
957YCHAR *yaffs_clone_str(const YCHAR *str);
958void yaffs_link_fixup(struct yaffs_dev *dev, struct list_head *hard_list);
959void yaffs_block_became_dirty(struct yaffs_dev *dev, int block_no);
960int yaffs_update_oh(struct yaffs_obj *in, const YCHAR *name,
961		    int force, int is_shrink, int shadows,
962		    struct yaffs_xattr_mod *xop);
963void yaffs_handle_shadowed_obj(struct yaffs_dev *dev, int obj_id,
964			       int backward_scanning);
965int yaffs_check_alloc_available(struct yaffs_dev *dev, int n_chunks);
966struct yaffs_tnode *yaffs_get_tnode(struct yaffs_dev *dev);
967struct yaffs_tnode *yaffs_add_find_tnode_0(struct yaffs_dev *dev,
968					   struct yaffs_file_var *file_struct,
969					   u32 chunk_id,
970					   struct yaffs_tnode *passed_tn);
971
972int yaffs_do_file_wr(struct yaffs_obj *in, const u8 *buffer, loff_t offset,
973		     int n_bytes, int write_trhrough);
974void yaffs_resize_file_down(struct yaffs_obj *obj, loff_t new_size);
975void yaffs_skip_rest_of_block(struct yaffs_dev *dev);
976
977int yaffs_count_free_chunks(struct yaffs_dev *dev);
978
979struct yaffs_tnode *yaffs_find_tnode_0(struct yaffs_dev *dev,
980				       struct yaffs_file_var *file_struct,
981				       u32 chunk_id);
982
983u32 yaffs_get_group_base(struct yaffs_dev *dev, struct yaffs_tnode *tn,
984			 unsigned pos);
985
986int yaffs_is_non_empty_dir(struct yaffs_obj *obj);
987
988int yaffs_guts_format_dev(struct yaffs_dev *dev);
989
990void yaffs_addr_to_chunk(struct yaffs_dev *dev, loff_t addr,
991				int *chunk_out, u32 *offset_out);
992/*
993 * Marshalling functions to get loff_t file sizes into aand out of
994 * object headers.
995 */
996void yaffs_oh_size_load(struct yaffs_obj_hdr *oh, loff_t fsize);
997loff_t yaffs_oh_to_size(struct yaffs_obj_hdr *oh);
998loff_t yaffs_max_file_size(struct yaffs_dev *dev);
999
1000/*
1001 * Debug function to count number of blocks in each state
1002 * NB Needs to be called with correct number of integers
1003 */
1004
1005void yaffs_count_blocks_by_state(struct yaffs_dev *dev, int bs[10]);
1006
1007int yaffs_find_chunk_in_file(struct yaffs_obj *in, int inode_chunk,
1008				    struct yaffs_ext_tags *tags);
1009
1010#endif
1011