diff --git a/src/add-ons/kernel/file_systems/bfs/BPlusTree.cpp b/src/add-ons/kernel/file_systems/bfs/BPlusTree.cpp
index d8950316cb..d4d8fe6d4b 100644
--- a/src/add-ons/kernel/file_systems/bfs/BPlusTree.cpp
+++ b/src/add-ons/kernel/file_systems/bfs/BPlusTree.cpp
@@ -1036,7 +1036,7 @@ BPlusTree::_SplitNode(bplustree_node *node, off_t nodeOffset,
 		}
 		out++;
 
-		if (round_up(sizeof(bplustree_node) + bytesBefore + bytesAfter + bytes)
+		if (key_align(sizeof(bplustree_node) + bytesBefore + bytesAfter + bytes)
 				+ out * (sizeof(uint16) + sizeof(off_t)) >= size) {
 			// we have found the number of keys in the new node!
 			break;
@@ -1303,7 +1303,7 @@ BPlusTree::Insert(Transaction &transaction, const uint8 *key, uint16 keyLength,
 			return B_IO_ERROR;
 
 		// is the node big enough to hold the pair?
-		if (int32(round_up(sizeof(bplustree_node)
+		if (int32(key_align(sizeof(bplustree_node)
 				+ writableNode->AllKeyLength() + keyLength)
 				+ (writableNode->NumKeys() + 1) * (sizeof(uint16)
 				+ sizeof(off_t))) < fNodeSize) {
diff --git a/src/add-ons/kernel/file_systems/bfs/BPlusTree.h b/src/add-ons/kernel/file_systems/bfs/BPlusTree.h
index bb2c5d5688..369b3e6957 100644
--- a/src/add-ons/kernel/file_systems/bfs/BPlusTree.h
+++ b/src/add-ons/kernel/file_systems/bfs/BPlusTree.h
@@ -115,7 +115,7 @@ struct bplustree_node {
 enum bplustree_traversing {
 	BPLUSTREE_FORWARD = 1,
 	BPLUSTREE_BACKWARD = -1,
-	
+
 	BPLUSTREE_BEGIN = 0,
 	BPLUSTREE_END = 1
 };
@@ -239,7 +239,7 @@ class BPlusTree {
 		status_t	_SeekDown(Stack<node_and_key> &stack, const uint8 *key,
 						uint16 keyLength);
 
-		status_t	_FindFreeDuplicateFragment(Transaction &transaction, 
+		status_t	_FindFreeDuplicateFragment(Transaction &transaction,
 						const bplustree_node *node, CachedNode &cached,
 						off_t *_offset, bplustree_node **_fragment,
 						uint32 *_index);
@@ -424,7 +424,7 @@ TreeIterator::GetPreviousEntry(void *key, uint16 *keyLength, uint16 maxLength,
 //	#pragma mark - bplustree_header inline functions
 
 
-inline bool 
+inline bool
 bplustree_header::CheckNode(bplustree_node *node) const
 {
 	// sanity checks (links, all_key_count)
@@ -450,7 +450,7 @@ bplustree_header::IsValidLink(off_t link) const
 inline uint16 *
 bplustree_node::KeyLengths() const
 {
-	return (uint16 *)(((char *)this) + round_up(sizeof(bplustree_node)
+	return (uint16 *)(((char *)this) + key_align(sizeof(bplustree_node)
 		+ AllKeyLength()));
 }
 
@@ -472,12 +472,12 @@ bplustree_node::Keys() const
 inline int32
 bplustree_node::Used() const
 {
-	return round_up(sizeof(bplustree_node) + AllKeyLength()) + NumKeys()
+	return key_align(sizeof(bplustree_node) + AllKeyLength()) + NumKeys()
 		* (sizeof(uint16) + sizeof(off_t));
 }
 
 
-inline bool 
+inline bool
 bplustree_node::IsLeaf() const
 {
 	return OverflowLink() == BPLUSTREE_NULL;
@@ -514,7 +514,7 @@ bplustree_node::MakeLink(uint8 type, off_t link, uint32 fragmentIndex)
 }
 
 
-inline bool 
+inline bool
 bplustree_node::IsDuplicate(off_t link)
 {
 	return (LinkType(link)
diff --git a/src/add-ons/kernel/file_systems/bfs/Inode.cpp b/src/add-ons/kernel/file_systems/bfs/Inode.cpp
index 0bb7dc379e..614b277bbc 100644
--- a/src/add-ons/kernel/file_systems/bfs/Inode.cpp
+++ b/src/add-ons/kernel/file_systems/bfs/Inode.cpp
@@ -1280,7 +1280,7 @@ Inode::FindBlockRun(off_t pos, block_run &run, off_t &offset)
 
 	// find matching block run
 
-	if (data->MaxDirectRange() > 0 && pos >= data->MaxDirectRange()) {
+	if (data->MaxIndirectRange() > 0 && pos >= data->MaxDirectRange()) {
 		if (data->MaxDoubleIndirectRange() > 0
 			&& pos >= data->MaxIndirectRange()) {
 			// access to double indirect blocks
@@ -1581,7 +1581,7 @@ Inode::_GrowStream(Transaction &transaction, off_t size)
 		blocksRequested = blocksNeeded;
 		if (minimum > 1) {
 			// make sure that "blocks" is a multiple of minimum
-			blocksRequested = (blocksRequested + minimum - 1) & ~(minimum - 1);
+			blocksRequested = round_up(blocksRequested, minimum);
 		}
 
 		// Direct block range
@@ -1694,8 +1694,7 @@ Inode::_GrowStream(Transaction &transaction, off_t size)
 					return status;
 
 				blocksNeeded += rest;
-				blocksRequested = (blocksNeeded + NUM_ARRAY_BLOCKS - 1)
-					& ~(NUM_ARRAY_BLOCKS - 1);
+				blocksRequested = round_up(blocksNeeded, NUM_ARRAY_BLOCKS);
 				minimum = NUM_ARRAY_BLOCKS;
 					// we make sure here that we have at minimum
 					// NUM_ARRAY_BLOCKS allocated, so if the allocation
@@ -2042,8 +2041,7 @@ Inode::NeedsTrimming()
 	if (IsIndex() || IsDeleted())
 		return false;
 
-	off_t roundedSize = (Size() + fVolume->BlockSize() - 1)
-		& ~(fVolume->BlockSize() - 1);
+	off_t roundedSize = round_up(Size(), fVolume->BlockSize());
 
 	return Node().data.MaxDirectRange() > roundedSize
 		|| Node().data.MaxIndirectRange() > roundedSize
diff --git a/src/add-ons/kernel/file_systems/bfs/Utility.h b/src/add-ons/kernel/file_systems/bfs/Utility.h
index 4f673fb0b7..2dd196e8da 100644
--- a/src/add-ons/kernel/file_systems/bfs/Utility.h
+++ b/src/add-ons/kernel/file_systems/bfs/Utility.h
@@ -33,4 +33,14 @@ sorted_array::Find(off_t value) const
 	return _FindInternal(value, i) ? i : -1;
 }
 
+
+/*!	\a to must be a power of 2.
+*/
+template<typename IntType, typename RoundType>
+inline IntType
+round_up(const IntType& value, const RoundType& to)
+{
+	return (value + (to - 1)) & ~((IntType)to - 1);
+}
+
 #endif	/* UTILITY_H */
diff --git a/src/add-ons/kernel/file_systems/bfs/bfs.h b/src/add-ons/kernel/file_systems/bfs/bfs.h
index 9efda687e1..0d838f370b 100644
--- a/src/add-ons/kernel/file_systems/bfs/bfs.h
+++ b/src/add-ons/kernel/file_systems/bfs/bfs.h
@@ -160,8 +160,8 @@ struct small_data {
 
 // the file name is part of the small_data structure
 #define FILE_NAME_TYPE			'CSTR'
-#define FILE_NAME_NAME			0x13 
-#define FILE_NAME_NAME_LENGTH	1 
+#define FILE_NAME_NAME			0x13
+#define FILE_NAME_NAME_LENGTH	1
 
 
 //**************************************
@@ -193,7 +193,7 @@ struct bfs_inode {
 	int32		pad[4];
 
 	small_data	small_data_start[0];
-	
+
 	int32 Magic1() const { return BFS_ENDIAN_TO_HOST_INT32(magic1); }
 	int32 UserID() const { return BFS_ENDIAN_TO_HOST_INT32(uid); }
 	int32 GroupID() const { return BFS_ENDIAN_TO_HOST_INT32(gid); }
@@ -207,7 +207,7 @@ struct bfs_inode {
 
 	status_t InitCheck(Volume *volume);
 		// defined in Inode.cpp
-} _PACKED;	
+} _PACKED;
 
 #define INODE_MAGIC1			0x3bbe0ad9
 #define INODE_TIME_SHIFT		16
@@ -267,8 +267,8 @@ get_shift(uint64 i)
 	return c;
 }
 
-inline int32
-round_up(uint32 data)
+inline uint32
+key_align(uint32 data)
 {
 	// rounds up to the next off_t boundary
 	return (data + sizeof(off_t) - 1) & ~(sizeof(off_t) - 1);
@@ -304,7 +304,7 @@ block_run::IsZero() const
 }
 
 
-inline bool 
+inline bool
 block_run::MergeableWith(block_run run) const
 {
 	// 65535 is the maximum allowed run size for BFS
@@ -352,7 +352,7 @@ small_data::Data() const
 }
 
 
-inline uint32 
+inline uint32
 small_data::Size() const
 {
 	return sizeof(small_data) + NameSize() + 3 + DataSize() + 1;
diff --git a/src/add-ons/kernel/file_systems/bfs/kernel_interface.cpp b/src/add-ons/kernel/file_systems/bfs/kernel_interface.cpp
index e9681aa32d..7cba30a671 100644
--- a/src/add-ons/kernel/file_systems/bfs/kernel_interface.cpp
+++ b/src/add-ons/kernel/file_systems/bfs/kernel_interface.cpp
@@ -431,7 +431,7 @@ bfs_get_file_map(fs_volume *_volume, fs_vnode *_node, off_t offset, size_t size,
 	Inode *inode = (Inode *)_node->private_node;
 
 	int32 blockShift = volume->BlockShift();
-	size_t index = 0, max = *_count;
+	uint32 index = 0, max = *_count;
 	block_run run;
 	off_t fileOffset;
 
@@ -445,21 +445,20 @@ bfs_get_file_map(fs_volume *_volume, fs_vnode *_node, off_t offset, size_t size,
 		vecs[index].offset = volume->ToOffset(run) + offset - fileOffset;
 		vecs[index].length = (run.Length() << blockShift) - offset + fileOffset;
 
-		offset += vecs[index].length;
-
 		// are we already done?
 		if (size <= vecs[index].length
-			|| offset >= inode->Size()) {
-			if (offset > inode->Size()) {
+			|| offset + vecs[index].length >= inode->Size()) {
+			if (offset + vecs[index].length > inode->Size()) {
 				// make sure the extent ends with the last official file
 				// block (without taking any preallocations into account)
-				vecs[index].length = (inode->Size() - fileOffset
-					+ volume->BlockSize() - 1) & ~(volume->BlockSize() - 1);
+				vecs[index].length = round_up(inode->Size() - offset,
+					volume->BlockSize());
 			}
 			*_count = index + 1;
 			return B_OK;
 		}
 
+		offset += vecs[index].length;
 		size -= vecs[index].length;
 		index++;