2 * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
4 * Copyright (C) 2002-2010 Aleph One Ltd.
5 * for Toby Churchill Ltd and Brightstar Engineering
7 * Created by Charles Manning <charles@aleph1.co.uk>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
13 #include "yaffs_yaffs1.h"
15 #include "yaffs_trace.h"
16 #include "yaffs_bitmap.h"
17 #include "yaffs_getblockinfo.h"
18 #include "yaffs_nand.h"
21 int yaffs1_Scan(yaffs_Device *dev)
23 yaffs_ExtendedTags tags;
33 yaffs_BlockState state;
34 yaffs_Object *hardList = NULL;
37 yaffs_ObjectHeader *oh;
43 struct yaffs_ShadowFixerStruct *shadowFixerList = NULL;
51 (TSTR("yaffs1_Scan starts intstartblk %d intendblk %d..." TENDSTR),
52 dev->internalStartBlock, dev->internalEndBlock));
54 chunkData = yaffs_GetTempBuffer(dev, __LINE__);
56 dev->sequenceNumber = YAFFS_LOWEST_SEQUENCE_NUMBER;
58 /* Scan all the blocks to determine their state */
60 for (blk = dev->internalStartBlock; blk <= dev->internalEndBlock; blk++) {
61 yaffs_ClearChunkBits(dev, blk);
63 bi->softDeletions = 0;
65 yaffs_QueryInitialBlockState(dev, blk, &state, &sequenceNumber);
67 bi->blockState = state;
68 bi->sequenceNumber = sequenceNumber;
70 if (bi->sequenceNumber == YAFFS_SEQUENCE_BAD_BLOCK)
71 bi->blockState = state = YAFFS_BLOCK_STATE_DEAD;
73 T(YAFFS_TRACE_SCAN_DEBUG,
74 (TSTR("Block scanning block %d state %d seq %d" TENDSTR), blk,
75 state, sequenceNumber));
77 if (state == YAFFS_BLOCK_STATE_DEAD) {
78 T(YAFFS_TRACE_BAD_BLOCKS,
79 (TSTR("block %d is bad" TENDSTR), blk));
80 } else if (state == YAFFS_BLOCK_STATE_EMPTY) {
81 T(YAFFS_TRACE_SCAN_DEBUG,
82 (TSTR("Block empty " TENDSTR)));
84 dev->nFreeChunks += dev->param.nChunksPerBlock;
89 startIterator = dev->internalStartBlock;
90 endIterator = dev->internalEndBlock;
92 /* For each block.... */
93 for (blockIterator = startIterator; !alloc_failed && blockIterator <= endIterator;
102 bi = yaffs_GetBlockInfo(dev, blk);
103 state = bi->blockState;
107 /* For each chunk in each block that needs scanning....*/
108 for (c = 0; !alloc_failed && c < dev->param.nChunksPerBlock &&
109 state == YAFFS_BLOCK_STATE_NEEDS_SCANNING; c++) {
110 /* Read the tags and decide what to do */
111 chunk = blk * dev->param.nChunksPerBlock + c;
113 result = yaffs_ReadChunkWithTagsFromNAND(dev, chunk, NULL,
116 /* Let's have a good look at this chunk... */
118 if (tags.eccResult == YAFFS_ECC_RESULT_UNFIXED || tags.chunkDeleted) {
124 /*T((" %d %d deleted\n",blk,c)); */
125 } else if (!tags.chunkUsed) {
126 /* An unassigned chunk in the block
127 * This means that either the block is empty or
128 * this is the one being allocated from
132 /* We're looking at the first chunk in the block so the block is unused */
133 state = YAFFS_BLOCK_STATE_EMPTY;
134 dev->nErasedBlocks++;
136 /* this is the block being allocated from */
139 (" Allocating from %d %d" TENDSTR),
141 state = YAFFS_BLOCK_STATE_ALLOCATING;
142 dev->allocationBlock = blk;
143 dev->allocationPage = c;
144 dev->allocationBlockFinder = blk;
145 /* Set block finder here to encourage the allocator to go forth from here. */
149 dev->nFreeChunks += (dev->param.nChunksPerBlock - c);
150 } else if (tags.chunkId > 0) {
151 /* chunkId > 0 so it is a data chunk... */
154 yaffs_SetChunkBit(dev, blk, c);
157 in = yaffs_FindOrCreateObjectByNumber(dev,
160 YAFFS_OBJECT_TYPE_FILE);
161 /* PutChunkIntoFile checks for a clash (two data chunks with
169 if (!yaffs_PutChunkIntoFile(in, tags.chunkId, chunk, 1))
174 (tags.chunkId - 1) * dev->nDataBytesPerChunk +
177 in->variantType == YAFFS_OBJECT_TYPE_FILE
178 && in->variant.fileVariant.scannedFileSize <
180 in->variant.fileVariant.
181 scannedFileSize = endpos;
182 if (!dev->param.useHeaderFileSize) {
183 in->variant.fileVariant.
185 in->variant.fileVariant.
190 /* T((" %d %d data %d %d\n",blk,c,tags.objectId,tags.chunkId)); */
192 /* chunkId == 0, so it is an ObjectHeader.
193 * Thus, we read in the object header and make the object
195 yaffs_SetChunkBit(dev, blk, c);
198 result = yaffs_ReadChunkWithTagsFromNAND(dev, chunk,
202 oh = (yaffs_ObjectHeader *) chunkData;
204 in = yaffs_FindObjectByNumber(dev,
206 if (in && in->variantType != oh->type) {
207 /* This should not happen, but somehow
208 * Wev'e ended up with an objectId that has been reused but not yet
209 * deleted, and worse still it has changed type. Delete the old object.
212 yaffs_DeleteObject(in);
217 in = yaffs_FindOrCreateObjectByNumber(dev,
225 if (in && oh->shadowsObject > 0) {
227 struct yaffs_ShadowFixerStruct *fixer;
228 fixer = YMALLOC(sizeof(struct yaffs_ShadowFixerStruct));
230 fixer->next = shadowFixerList;
231 shadowFixerList = fixer;
232 fixer->objectId = tags.objectId;
233 fixer->shadowedId = oh->shadowsObject;
238 if (in && in->valid) {
239 /* We have already filled this one. We have a duplicate and need to resolve it. */
241 unsigned existingSerial = in->serial;
242 unsigned newSerial = tags.serialNumber;
244 if (((existingSerial + 1) & 3) == newSerial) {
245 /* Use new one - destroy the exisiting one */
246 yaffs_DeleteChunk(dev,
251 /* Use existing - destroy this one. */
252 yaffs_DeleteChunk(dev, chunk, 1,
257 if (in && !in->valid &&
258 (tags.objectId == YAFFS_OBJECTID_ROOT ||
259 tags.objectId == YAFFS_OBJECTID_LOSTNFOUND)) {
260 /* We only load some info, don't fiddle with directory structure */
262 in->variantType = oh->type;
264 in->yst_mode = oh->yst_mode;
265 #ifdef CONFIG_YAFFS_WINCE
266 in->win_atime[0] = oh->win_atime[0];
267 in->win_ctime[0] = oh->win_ctime[0];
268 in->win_mtime[0] = oh->win_mtime[0];
269 in->win_atime[1] = oh->win_atime[1];
270 in->win_ctime[1] = oh->win_ctime[1];
271 in->win_mtime[1] = oh->win_mtime[1];
273 in->yst_uid = oh->yst_uid;
274 in->yst_gid = oh->yst_gid;
275 in->yst_atime = oh->yst_atime;
276 in->yst_mtime = oh->yst_mtime;
277 in->yst_ctime = oh->yst_ctime;
278 in->yst_rdev = oh->yst_rdev;
280 in->hdrChunk = chunk;
281 in->serial = tags.serialNumber;
283 } else if (in && !in->valid) {
284 /* we need to load this info */
287 in->variantType = oh->type;
289 in->yst_mode = oh->yst_mode;
290 #ifdef CONFIG_YAFFS_WINCE
291 in->win_atime[0] = oh->win_atime[0];
292 in->win_ctime[0] = oh->win_ctime[0];
293 in->win_mtime[0] = oh->win_mtime[0];
294 in->win_atime[1] = oh->win_atime[1];
295 in->win_ctime[1] = oh->win_ctime[1];
296 in->win_mtime[1] = oh->win_mtime[1];
298 in->yst_uid = oh->yst_uid;
299 in->yst_gid = oh->yst_gid;
300 in->yst_atime = oh->yst_atime;
301 in->yst_mtime = oh->yst_mtime;
302 in->yst_ctime = oh->yst_ctime;
303 in->yst_rdev = oh->yst_rdev;
305 in->hdrChunk = chunk;
306 in->serial = tags.serialNumber;
308 yaffs_SetObjectNameFromOH(in, oh);
311 /* directory stuff...
316 yaffs_FindOrCreateObjectByNumber
317 (dev, oh->parentObjectId,
318 YAFFS_OBJECT_TYPE_DIRECTORY);
321 if (parent && parent->variantType ==
322 YAFFS_OBJECT_TYPE_UNKNOWN) {
323 /* Set up as a directory */
324 parent->variantType =
325 YAFFS_OBJECT_TYPE_DIRECTORY;
326 YINIT_LIST_HEAD(&parent->variant.
329 } else if (!parent || parent->variantType !=
330 YAFFS_OBJECT_TYPE_DIRECTORY) {
331 /* Hoosterman, another problem....
332 * We're trying to use a non-directory as a directory
337 ("yaffs tragedy: attempting to use non-directory as a directory in scan. Put in lost+found."
339 parent = dev->lostNFoundDir;
342 yaffs_AddObjectToDirectory(parent, in);
344 if (0 && (parent == dev->deletedDir ||
345 parent == dev->unlinkedDir)) {
346 in->deleted = 1; /* If it is unlinked at start up then it wants deleting */
347 dev->nDeletedFiles++;
349 /* Note re hardlinks.
350 * Since we might scan a hardlink before its equivalent object is scanned
351 * we put them all in a list.
352 * After scanning is complete, we should have all the objects, so we run through this
353 * list and fix up all the chains.
356 switch (in->variantType) {
357 case YAFFS_OBJECT_TYPE_UNKNOWN:
358 /* Todo got a problem */
360 case YAFFS_OBJECT_TYPE_FILE:
361 if (dev->param.useHeaderFileSize)
363 in->variant.fileVariant.
368 case YAFFS_OBJECT_TYPE_HARDLINK:
369 in->variant.hardLinkVariant.
371 oh->equivalentObjectId;
373 (struct ylist_head *)
377 case YAFFS_OBJECT_TYPE_DIRECTORY:
380 case YAFFS_OBJECT_TYPE_SPECIAL:
383 case YAFFS_OBJECT_TYPE_SYMLINK:
384 in->variant.symLinkVariant.alias =
385 yaffs_CloneString(oh->alias);
386 if (!in->variant.symLinkVariant.alias)
395 if (state == YAFFS_BLOCK_STATE_NEEDS_SCANNING) {
396 /* If we got this far while scanning, then the block is fully allocated.*/
397 state = YAFFS_BLOCK_STATE_FULL;
400 if (state == YAFFS_BLOCK_STATE_ALLOCATING) {
401 /* If the block was partially allocated then treat it as fully allocated.*/
402 state = YAFFS_BLOCK_STATE_FULL;
403 dev->allocationBlock = -1;
406 bi->blockState = state;
408 /* Now let's see if it was dirty */
409 if (bi->pagesInUse == 0 &&
410 !bi->hasShrinkHeader &&
411 bi->blockState == YAFFS_BLOCK_STATE_FULL) {
412 yaffs_BlockBecameDirty(dev, blk);
418 /* Ok, we've done all the scanning.
419 * Fix up the hard link chains.
420 * We should now have scanned all the objects, now it's time to add these
424 yaffs_HardlinkFixup(dev, hardList);
426 /* Fix up any shadowed objects */
428 struct yaffs_ShadowFixerStruct *fixer;
431 while (shadowFixerList) {
432 fixer = shadowFixerList;
433 shadowFixerList = fixer->next;
434 /* Complete the rename transaction by deleting the shadowed object
435 * then setting the object header to unshadowed.
437 obj = yaffs_FindObjectByNumber(dev, fixer->shadowedId);
439 yaffs_DeleteObject(obj);
441 obj = yaffs_FindObjectByNumber(dev, fixer->objectId);
444 yaffs_UpdateObjectHeader(obj, NULL, 1, 0, 0, NULL);
450 yaffs_ReleaseTempBuffer(dev, chunkData, __LINE__);
455 T(YAFFS_TRACE_SCAN, (TSTR("yaffs1_Scan ends" TENDSTR)));