New partial block handing to improve robustness
[yaffs2.git] / yaffs_guts.c
index 9517550b20f8f78c3c0163d64e054d60a518635c..4af4c4094a4d348446870e070d79ef62c09d3f95 100644 (file)
@@ -12,7 +12,7 @@
  */
 
 const char *yaffs_guts_c_version =
-    "$Id: yaffs_guts.c,v 1.95 2009-11-11 01:40:41 charles Exp $";
+    "$Id: yaffs_guts.c,v 1.99 2009-12-14 22:03:05 charles Exp $";
 
 #include "yportenv.h"
 
@@ -113,6 +113,12 @@ static yaffs_Tnode *yaffs_FindLevel0Tnode(yaffs_Device *dev,
                                        yaffs_FileStructure *fStruct,
                                        __u32 chunkId);
 
+static void yaffs_SkipRestOfBlock(yaffs_Device *dev);
+static int yaffs_VerifyChunkWritten(yaffs_Device *dev,
+                                       int chunkInNAND,
+                                       const __u8 *data,
+                                       yaffs_ExtendedTags *tags);
+
 /* Function to calculate chunk and offset */
 
 static void yaffs_AddrToChunk(yaffs_Device *dev, loff_t addr, int *chunkOut,
@@ -918,6 +924,29 @@ static int yaffs_CheckChunkErased(struct yaffs_DeviceStruct *dev,
 
 }
 
+
+static int yaffs_VerifyChunkWritten(yaffs_Device *dev,
+                                       int chunkInNAND,
+                                       const __u8 *data,
+                                       yaffs_ExtendedTags *tags)
+{
+       int retval = YAFFS_OK;
+       yaffs_ExtendedTags tempTags;
+       __u8 *buffer = yaffs_GetTempBuffer(dev,__LINE__);
+       int result;
+       
+       result = yaffs_ReadChunkWithTagsFromNAND(dev,chunkInNAND,buffer,&tempTags);
+       if(memcmp(buffer,data,dev->nDataBytesPerChunk) ||
+               tempTags.objectId != tags->objectId ||
+               tempTags.chunkId  != tags->chunkId ||
+               tempTags.byteCount != tags->byteCount)
+               retval = YAFFS_FAIL;
+
+       yaffs_ReleaseTempBuffer(dev, buffer, __LINE__);
+
+       return retval;
+}
+
 static int yaffs_WriteNewChunkWithTagsToNAND(struct yaffs_DeviceStruct *dev,
                                        const __u8 *data,
                                        yaffs_ExtendedTags *tags,
@@ -957,12 +986,11 @@ static int yaffs_WriteNewChunkWithTagsToNAND(struct yaffs_DeviceStruct *dev,
                 * chunk due to power loss.  This checking policy should
                 * catch that case with very few checks and thus save a
                 * lot of checks that are most likely not needed.
+                *
+                * Mods to the above
+                * If an erase check fails or the write fails we skip the 
+                * rest of the block.
                 */
-               if (bi->gcPrioritise) {
-                       yaffs_DeleteChunk(dev, chunk, 1, __LINE__);
-                       /* try another chunk */
-                       continue;
-               }
 
                /* let's give it a try */
                attempts++;
@@ -977,20 +1005,30 @@ static int yaffs_WriteNewChunkWithTagsToNAND(struct yaffs_DeviceStruct *dev,
                                (TSTR("**>> yaffs chunk %d was not erased"
                                TENDSTR), chunk));
 
-                               /* try another chunk */
+                               /* If not erased, delete this one,
+                                * skip rest of block and
+                                * try another chunk */
+                                yaffs_DeleteChunk(dev,chunk,1,__LINE__);
+                                yaffs_SkipRestOfBlock(dev);
                                continue;
                        }
-                       bi->skipErasedCheck = 1;
                }
 
                writeOk = yaffs_WriteChunkWithTagsToNAND(dev, chunk,
                                data, tags);
+
+               if(!bi->skipErasedCheck)
+                       writeOk = yaffs_VerifyChunkWritten(dev, chunk, data, tags);
+
                if (writeOk != YAFFS_OK) {
+                       /* Clean up aborted write, skip to next block and
+                        * try another chunk */
                        yaffs_HandleWriteChunkError(dev, chunk, erasedOk);
-                       /* try another chunk */
                        continue;
                }
 
+               bi->skipErasedCheck = 1;
+
                /* Copy the data into the robustification buffer */
                yaffs_HandleWriteChunkOk(dev, chunk, data, tags);
 
@@ -1100,6 +1138,7 @@ static void yaffs_HandleWriteChunkError(yaffs_Device *dev, int chunkInNAND,
 
        /* Delete the chunk */
        yaffs_DeleteChunk(dev, chunkInNAND, 1, __LINE__);
+       yaffs_SkipRestOfBlock(dev);
 }
 
 
@@ -1130,7 +1169,7 @@ static void yaffs_SetObjectName(yaffs_Object *obj, const YCHAR *name)
 {
 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
        memset(obj->shortName, 0, sizeof(YCHAR) * (YAFFS_SHORT_NAME_LENGTH+1));
-       if (name && yaffs_strlen(name) <= YAFFS_SHORT_NAME_LENGTH)
+       if (name && yaffs_strnlen(name,YAFFS_SHORT_NAME_LENGTH+1) <= YAFFS_SHORT_NAME_LENGTH)
                yaffs_strcpy(obj->shortName, name);
        else
                obj->shortName[0] = _Y('\0');
@@ -1864,10 +1903,14 @@ static int yaffs_CreateFreeObjects(yaffs_Device *dev, int nObjects)
        list = YMALLOC(sizeof(yaffs_ObjectList));
 
        if (!newObjects || !list) {
-               if (newObjects)
+               if (newObjects){
                        YFREE(newObjects);
-               if (list)
+                       newObjects = NULL;
+               }
+               if (list){
                        YFREE(list);
+                       list = NULL;
+               }
                T(YAFFS_TRACE_ALLOCATE,
                  (TSTR("yaffs: Could not allocate more objects" TENDSTR)));
                return YAFFS_FAIL;
@@ -2011,6 +2054,7 @@ static void yaffs_FreeObject(yaffs_Object *tn)
 
 #ifdef VALGRIND_TEST
        YFREE(tn);
+       tn = NULL;
 #else
        /* Link into the free list. */
        tn->siblings.next = (struct ylist_head *)(dev->freeObjects);
@@ -2252,13 +2296,17 @@ static yaffs_Object *yaffs_FindOrCreateObjectByNumber(yaffs_Device *dev,
 static YCHAR *yaffs_CloneString(const YCHAR *str)
 {
        YCHAR *newStr = NULL;
+       int len;
 
-       if (str && *str) {
-               newStr = YMALLOC((yaffs_strlen(str) + 1) * sizeof(YCHAR));
-               if (newStr)
-                       yaffs_strcpy(newStr, str);
-       }
+       if (!str)
+               str = _Y("");
 
+       len = yaffs_strnlen(str,YAFFS_MAX_ALIAS_LENGTH);
+       newStr = YMALLOC((len + 1) * sizeof(YCHAR));
+       if (newStr){
+               yaffs_strncpy(newStr, str,len);
+               newStr[len] = 0;
+       }
        return newStr;
 
 }
@@ -2266,7 +2314,7 @@ static YCHAR *yaffs_CloneString(const YCHAR *str)
 /*
  * Mknod (create) a new object.
  * equivalentObject only has meaning for a hard link;
- * aliasString only has meaning for a sumlink.
+ * aliasString only has meaning for a symlink.
  * rdev only has meaning for devices (a subset of special objects)
  */
 
@@ -2493,7 +2541,7 @@ int yaffs_RenameObject(yaffs_Object *oldDir, const YCHAR *oldName,
                force = 1;
 #endif
 
-       if(yaffs_strlen(newName) > YAFFS_MAX_NAME_LENGTH)
+       if(yaffs_strnlen(newName,YAFFS_MAX_NAME_LENGTH+1) > YAFFS_MAX_NAME_LENGTH)
                /* ENAMETOOLONG */
                return YAFFS_FAIL;
 
@@ -2970,6 +3018,22 @@ static int yaffs_GetErasedChunks(yaffs_Device *dev)
 
 }
 
+/*
+ * yaffs_SkipRestOfBlock() skips over the rest of the allocation block
+ * if we don't want to write to it.
+ */
+static void yaffs_SkipRestOfBlock(yaffs_Device *dev)
+{
+       if(dev->allocationBlock > 0){
+               yaffs_BlockInfo *bi = yaffs_GetBlockInfo(dev, dev->allocationBlock);
+               if(bi->blockState == YAFFS_BLOCK_STATE_ALLOCATING){
+                       bi->blockState = YAFFS_BLOCK_STATE_FULL;
+                       dev->allocationBlock = -1;
+               }
+       }
+}
+
+
 static int yaffs_GarbageCollectBlock(yaffs_Device *dev, int block,
                int wholeBlock)
 {
@@ -3129,6 +3193,7 @@ static int yaffs_GarbageCollectBlock(yaffs_Device *dev, int block,
                                        if (tags.chunkId == 0) {
                                                /* It is an object Id,
                                                 * We need to nuke the shrinkheader flags first
+                                                * Also need to clean up shadowing.
                                                 * We no longer want the shrinkHeader flag since its work is done
                                                 * and if it is left in place it will mess up scanning.
                                                 */
@@ -3137,6 +3202,9 @@ static int yaffs_GarbageCollectBlock(yaffs_Device *dev, int block,
                                                oh = (yaffs_ObjectHeader *)buffer;
                                                oh->isShrink = 0;
                                                tags.extraIsShrinkHeader = 0;
+                                               oh->shadowsObject = 0;
+                                               oh->inbandShadowsObject = 0;
+                                               tags.extraShadows = 0;
 
                                                yaffs_VerifyObjectHeader(object, oh, &tags, 1);
                                        }
@@ -3715,6 +3783,7 @@ int yaffs_UpdateObjectHeader(yaffs_Object *in, const YCHAR *name, int force,
        int newChunkId;
        yaffs_ExtendedTags newTags;
        yaffs_ExtendedTags oldTags;
+       YCHAR *alias = NULL;
 
        __u8 *buffer = NULL;
        YCHAR oldName[YAFFS_MAX_NAME_LENGTH + 1];
@@ -3803,8 +3872,11 @@ int yaffs_UpdateObjectHeader(yaffs_Object *in, const YCHAR *name, int force,
                        /* Do nothing */
                        break;
                case YAFFS_OBJECT_TYPE_SYMLINK:
+                       alias = in->variant.symLinkVariant.alias;
+                       if(!alias)
+                               alias = _Y("no alias");
                        yaffs_strncpy(oh->alias,
-                                     in->variant.symLinkVariant.alias,
+                                       alias,
                                      YAFFS_MAX_ALIAS_LENGTH);
                        oh->alias[YAFFS_MAX_ALIAS_LENGTH] = 0;
                        break;
@@ -5083,13 +5155,17 @@ int yaffs_ResizeFile(yaffs_Object *in, loff_t newSize)
 
 loff_t yaffs_GetFileSize(yaffs_Object *obj)
 {
+       YCHAR *alias = NULL;
        obj = yaffs_GetEquivalentObject(obj);
 
        switch (obj->variantType) {
        case YAFFS_OBJECT_TYPE_FILE:
                return obj->variant.fileVariant.fileSize;
        case YAFFS_OBJECT_TYPE_SYMLINK:
-               return yaffs_strlen(obj->variant.symLinkVariant.alias);
+               alias = obj->variant.symLinkVariant.alias;
+               if(!alias)
+                       return 0;
+               return yaffs_strnlen(alias,YAFFS_MAX_ALIAS_LENGTH);
        default:
                return 0;
        }
@@ -5235,7 +5311,9 @@ static int yaffs_DeleteDirectory(yaffs_Object *obj)
 
 static int yaffs_DeleteSymLink(yaffs_Object *in)
 {
-       YFREE(in->variant.symLinkVariant.alias);
+       if(in->variant.symLinkVariant.alias)
+               YFREE(in->variant.symLinkVariant.alias);
+       in->variant.symLinkVariant.alias=NULL;
 
        return yaffs_DoGenericObjectDeletion(in);
 }
@@ -5735,7 +5813,7 @@ static int yaffs_Scan(yaffs_Device *dev)
                                        dev->allocationBlock = blk;
                                        dev->allocationPage = c;
                                        dev->allocationBlockFinder = blk;
-                                       /* Set it to here to encourage the allocator to go forth from here. */
+                                       /* Set block finder here to encourage the allocator to go forth from here. */
 
                                }
 
@@ -5981,12 +6059,6 @@ static int yaffs_Scan(yaffs_Device *dev)
                                                break;
                                        }
 
-/*
-                                       if (parent == dev->deletedDir) {
-                                               yaffs_DestroyObject(in);
-                                               bi->hasShrinkHeader = 1;
-                                       }
-*/
                                }
                        }
                }
@@ -5996,6 +6068,12 @@ static int yaffs_Scan(yaffs_Device *dev)
                        state = YAFFS_BLOCK_STATE_FULL;
                }
 
+               if (state == YAFFS_BLOCK_STATE_ALLOCATING) {
+                       /* If the block was partially allocated then treat it as fully allocated.*/
+                       state = YAFFS_BLOCK_STATE_FULL;
+                       dev->allocationBlock = -1;
+               }
+
                bi->blockState = state;
 
                /* Now let's see if it was dirty */
@@ -6338,13 +6416,9 @@ static int yaffs_ScanBackwards(yaffs_Device *dev)
                                                        dev->allocationBlockFinder = blk;
                                                } else {
                                                        /* This is a partially written block that is not
-                                                        * the current allocation block. This block must have
-                                                        * had a write failure, so set up for retirement.
+                                                        * the current allocation block.
                                                         */
 
-                                                        /* bi->needsRetiring = 1; ??? TODO */
-                                                        bi->gcPrioritise = 1;
-
                                                         T(YAFFS_TRACE_ALWAYS,
                                                         (TSTR("Partially written block %d detected" TENDSTR),
                                                         blk));
@@ -6606,6 +6680,7 @@ static int yaffs_ScanBackwards(yaffs_Device *dev)
                                                                           oh->
                                                                           shadowsObject,
                                                                           1);
+                                                       
 
 
                                                yaffs_SetObjectName(in, oh->name);
@@ -6737,6 +6812,7 @@ static int yaffs_ScanBackwards(yaffs_Device *dev)
                        state = YAFFS_BLOCK_STATE_FULL;
                }
 
+
                bi->blockState = state;
 
                /* Now let's see if it was dirty */
@@ -6747,6 +6823,8 @@ static int yaffs_ScanBackwards(yaffs_Device *dev)
                }
 
        }
+       
+       yaffs_SkipRestOfBlock(dev);
 
        if (altBlockIndex)
                YFREE_ALT(blockIndex);
@@ -7071,7 +7149,7 @@ int yaffs_GetObjectName(yaffs_Object *obj, YCHAR *name, int buffSize)
        }
 #ifdef CONFIG_YAFFS_SHORT_NAMES_IN_RAM
        else if (obj->shortName[0])
-               yaffs_strcpy(name, obj->shortName);
+               yaffs_strncpy(name, obj->shortName,YAFFS_SHORT_NAME_LENGTH+1);
 #endif
        else {
                int result;
@@ -7087,11 +7165,12 @@ int yaffs_GetObjectName(yaffs_Object *obj, YCHAR *name, int buffSize)
                                                        NULL);
                }
                yaffs_strncpy(name, oh->name, buffSize - 1);
+               name[buffSize-1]=0;
 
                yaffs_ReleaseTempBuffer(obj->myDev, buffer, __LINE__);
        }
 
-       return yaffs_strlen(name);
+       return yaffs_strnlen(name,buffSize-1);
 }
 
 int yaffs_GetObjectFileLength(yaffs_Object *obj)
@@ -7101,9 +7180,11 @@ int yaffs_GetObjectFileLength(yaffs_Object *obj)
 
        if (obj->variantType == YAFFS_OBJECT_TYPE_FILE)
                return obj->variant.fileVariant.fileSize;
-       if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK)
-               return yaffs_strlen(obj->variant.symLinkVariant.alias);
-       else {
+       if (obj->variantType == YAFFS_OBJECT_TYPE_SYMLINK){
+               if(!obj->variant.symLinkVariant.alias)
+                       return 0;
+               return yaffs_strnlen(obj->variant.symLinkVariant.alias,YAFFS_MAX_ALIAS_LENGTH);
+       } else {
                /* Only a directory should drop through to here */
                return obj->myDev->nDataBytesPerChunk;
        }