* Fixed wrong group block offset computation: the

ext2_super_block::first_data_block must be used; the superblock offset
  doesn't matter if the block size is greater than 2KB.
* Fixed block access beyond the 4GB limit - we need to cast the block to
  a 64 bit type in ext2_get_file_map() before shifting it.
* Tested with various larger ext3 disks, and everything seems to work fine.
* Added some optional debug output.
* Minor cleanup.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@26213 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/add-ons/kernel/file_systems/ext2/DirectoryIterator.cpp

@@ -11,6 +11,14 @@
 #include "Inode.h"
 
 
+//#define TRACE_EXT2
+#ifdef TRACE_EXT2
+#	define TRACE(x...) dprintf("\33[34mext2:\33[0m " x)
+#else
+#	define TRACE(x...) ;
+#endif
+
+
 DirectoryIterator::DirectoryIterator(Inode* inode)
 	:
 	fInode(inode),
@@ -24,7 +32,7 @@ DirectoryIterator::~DirectoryIterator()
 }
 
 
-status_t	
+status_t
 DirectoryIterator::GetNext(char* name, size_t* _nameLength, ino_t* _id)
 {
 	if (fOffset + sizeof(ext2_dir_entry) >= fInode->Size())
@@ -48,6 +56,10 @@ DirectoryIterator::GetNext(char* name, size_t* _nameLength, ino_t* _id)
 		fOffset += entry.Length();
 	}
 
+	TRACE("offset %Ld: entry ino %lu, length %u, name length %u, type %u\n",
+		fOffset, entry.InodeID(), entry.Length(), entry.NameLength(),
+		entry.FileType());
+
 	// read name
 
 	size_t length = entry.NameLength();

src/add-ons/kernel/file_systems/ext2/Inode.cpp

@@ -11,6 +11,14 @@
 #include "CachedBlock.h"
 
 
+//#define TRACE_EXT2
+#ifdef TRACE_EXT2
+#	define TRACE(x...) dprintf("\33[34mext2:\33[0m " x)
+#else
+#	define TRACE(x...) ;
+#endif
+
+
 Inode::Inode(Volume* volume, ino_t id)
 	:
 	fVolume(volume),
@@ -23,6 +31,7 @@ Inode::Inode(Volume* volume, ino_t id)
 
 	uint32 block;
 	if (volume->GetInodeBlock(id, block) == B_OK) {
+		TRACE("inode %Ld at block %lu\n", ID(), block);
 		ext2_inode* inodes = (ext2_inode*)block_cache_get(volume->BlockCache(),
 			block);
 		if (inodes != NULL)
@@ -150,7 +159,7 @@ Inode::FindBlock(off_t offset, uint32& block)
 		return B_ERROR;
 	}
 
-	//dprintf("FindBlock(offset %Ld): %lu\n", offset, block);
+	TRACE("inode %Ld: FindBlock(offset %Ld): %lu\n", ID(), offset, block);
 	return B_OK;
 }
 

src/add-ons/kernel/file_systems/ext2/Volume.cpp

@@ -20,6 +20,14 @@
 #include "Inode.h"
 
 
+//#define TRACE_EXT2
+#ifdef TRACE_EXT2
+#	define TRACE(x...) dprintf("\33[34mext2:\33[0m " x)
+#else
+#	define TRACE(x...) ;
+#endif
+
+
 class DeviceOpener {
 	public:
 		DeviceOpener(int fd, int mode);
@@ -268,13 +276,20 @@ Volume::Mount(const char* deviceName, uint32 flags)
 	// initialize short hands to the super block (to save byte swapping)
 	fBlockShift = fSuperBlock.BlockShift();
 	fBlockSize = 1UL << fSuperBlock.BlockShift();
+	fFirstDataBlock = fSuperBlock.FirstDataBlock();
 
-	fNumGroups = (fSuperBlock.NumBlocks() - fSuperBlock.FirstDataBlock() - 1)
+	fNumGroups = (fSuperBlock.NumBlocks() - fFirstDataBlock - 1)
 		/ fSuperBlock.BlocksPerGroup() + 1;
 	fGroupsPerBlock = fBlockSize / sizeof(ext2_block_group);
 
+	TRACE("block size %ld, num groups %ld, groups per block %ld, first %lu\n",
+		fBlockSize, fNumGroups, fGroupsPerBlock, fFirstDataBlock);
+	TRACE("features %lx, incompatible features %lx, read-only features %lx\n",
+		fSuperBlock.CompatibleFeatures(), fSuperBlock.IncompatibleFeatures(),
+		fSuperBlock.ReadOnlyFeatures());
+
 	uint32 blockCount = (fNumGroups + fGroupsPerBlock - 1) / fGroupsPerBlock;
-	
+
 	fGroupBlocks = (ext2_block_group**)malloc(blockCount * sizeof(void*));
 	if (fGroupBlocks == NULL)
 		return B_NO_MEMORY;
@@ -298,8 +313,9 @@ Volume::Mount(const char* deviceName, uint32 flags)
 		// all went fine
 		opener.Keep();
 		return B_OK;
-	} else
+	} else {
-		dprintf("ext2: could not create root node: get_vnode() failed!\n");
+		TRACE("could not create root node: get_vnode() failed!\n");
+	}
 
 	return status;
 }
@@ -344,7 +360,7 @@ Volume::_GroupBlockOffset(uint32 blockIndex)
 	if ((fSuperBlock.IncompatibleFeatures()
 			& EXT2_INCOMPATIBLE_FEATURE_META_GROUP) == 0
 		|| blockIndex < fSuperBlock.FirstMetaBlockGroup())
-		return EXT2_SUPER_BLOCK_OFFSET + fBlockSize * (1 + blockIndex);
+		return (fFirstDataBlock + blockIndex + 1) << fBlockShift;
 
 	panic("meta block");
 	return 0;
@@ -380,6 +396,9 @@ Volume::GetBlockGroup(int32 index, ext2_block_group** _group)
 		}
 
 		fGroupBlocks[blockIndex] = groupBlock;
+
+		TRACE("group [%ld]: inode table %ld\n", index,
+			(fGroupBlocks[blockIndex] + index % fGroupsPerBlock)->InodeTable());
 	}
 
 	*_group = fGroupBlocks[blockIndex] + index % fGroupsPerBlock;

src/add-ons/kernel/file_systems/ext2/Volume.h

@@ -62,6 +62,7 @@ private:
 	uint32				fFlags;
 	uint32				fBlockSize;
 	uint32				fBlockShift;
+	uint32				fFirstDataBlock;
 	uint32				fNumGroups;
 	uint32				fGroupsPerBlock;
 	ext2_block_group**	fGroupBlocks;

src/add-ons/kernel/file_systems/ext2/ext2.h

@@ -45,7 +45,7 @@ struct ext2_super_block {
 	uint16	block_group;
 	uint32	compatible_features;
 	uint32	incompatible_features;
-	uint32	readonly_features;
+	uint32	read_only_features;
 	uint8	uuid[16];
 	char	name[16];
 	char	last_mount_point[64];
@@ -53,7 +53,7 @@ struct ext2_super_block {
 	uint8	preallocated_blocks;
 	uint8	preallocated_directory_blocks;
 	uint16	_padding;
-	
+
 	// journaling ext3 support
 	uint8	journal_uuid[16];
 	uint32	journal_inode;
@@ -85,7 +85,7 @@ struct ext2_super_block {
 	uint32 CompatibleFeatures() const
 		{ return B_LENDIAN_TO_HOST_INT32(compatible_features); }
 	uint32 ReadOnlyFeatures() const
-		{ return B_LENDIAN_TO_HOST_INT32(readonly_features); }
+		{ return B_LENDIAN_TO_HOST_INT32(read_only_features); }
 	uint32 IncompatibleFeatures() const
 		{ return B_LENDIAN_TO_HOST_INT32(incompatible_features); }
 

src/add-ons/kernel/file_systems/ext2/kernel_interface.cpp

@@ -257,7 +257,7 @@ ext2_get_file_map(fs_volume* _volume, fs_vnode* _node, off_t offset,
 		if (status != B_OK)
 			return status;
 
-		off_t blockOffset = block << volume->BlockShift();
+		off_t blockOffset = (off_t)block << volume->BlockShift();
 		uint32 blockLength = volume->BlockSize();
 
 		if (index > 0 && vecs[index - 1].offset == blockOffset - blockLength) {