From e93b9c1fe4068dd5b07049c0926dbb910d20a99b Mon Sep 17 00:00:00 2001
From: John Hodge <tpg@mutabah.net>
Date: Tue, 17 Jul 2012 13:36:28 +0800
Subject: [PATCH] Modules/EXT2 - Working on write support

---
 KernelLand/Modules/Filesystems/Ext2/dir.c     | 52 +++++++++----------
 KernelLand/Modules/Filesystems/Ext2/ext2.c    | 40 +++++++++++---
 .../Modules/Filesystems/Ext2/ext2_common.h    |  2 +
 KernelLand/Modules/Filesystems/Ext2/write.c   |  5 ++
 4 files changed, 64 insertions(+), 35 deletions(-)

diff --git a/KernelLand/Modules/Filesystems/Ext2/dir.c b/KernelLand/Modules/Filesystems/Ext2/dir.c
index 0887ed28..30cc86ed 100644
--- a/KernelLand/Modules/Filesystems/Ext2/dir.c
+++ b/KernelLand/Modules/Filesystems/Ext2/dir.c
@@ -172,34 +172,32 @@ tVFS_Node *Ext2_FindDir(tVFS_Node *Node, const char *Filename)
  */
 int Ext2_MkNod(tVFS_Node *Parent, const char *Name, Uint Flags)
 {
-	#if 0
-	tVFS_Node	*child;
-	Uint64	inodeNum;
-	tExt2_Inode	inode;
-	inodeNum = Ext2_int_AllocateInode(Parent->ImplPtr, Parent->Inode);
-	
-	memset(&inode, 0, sizeof(tExt2_Inode));
+	ENTER("pParent sName xFlags", Parent, Name, Flags);
 	
-	// File type
-	inode.i_mode = 0664;
-	if( Flags & VFS_FFLAG_READONLY )
-		inode.i_mode &= ~0222;
-	if( Flags & VFS_FFLAG_SYMLINK )
-		inode.i_mode |= EXT2_S_IFLNK;
-	else if( Flags & VFS_FFLAG_DIRECTORY )
-		inode.i_mode |= EXT2_S_IFDIR | 0111;
-	
-	inode.i_uid = Threads_GetUID();
-	inode.i_gid = Threads_GetGID();
-	inode.i_ctime =
-		inode.i_mtime =
-		inode.i_atime = now() / 1000;
-	
-	child = Ext2_int_CreateNode(Parent->ImplPtr, inodeNum);
-	return Ext2_Link(Parent, child, Name);
-	#else
-	return 1;
-	#endif
+	Uint64 inodeNum = Ext2_int_AllocateInode(Parent->ImplPtr, Parent->Inode);
+	if( inodeNum == 0 ) {
+		return -1;
+	}
+	tVFS_Node *child = Ext2_int_CreateNode(Parent->ImplPtr, inodeNum);
+	if( !child ) {
+		Ext2_int_DereferenceInode(Parent->ImplPtr, inodeNum);
+		return -1;
+	}
+
+	child->Flags = Flags & (VFS_FFLAG_DIRECTORY|VFS_FFLAG_SYMLINK|VFS_FFLAG_READONLY);
+	child->UID = Threads_GetUID();
+	child->GID = Threads_GetGID();
+	child->CTime =
+		child->MTime =
+		child->ATime =
+		now();
+	child->ImplInt = 0;	// ImplInt is the link count
+	// TODO: Set up ACLs
+
+	int rv = Ext2_Link(Parent, Name, child);
+	child->Type->Close(child);
+	LEAVE('i', rv);
+	return rv;
 }
 
 /**
diff --git a/KernelLand/Modules/Filesystems/Ext2/ext2.c b/KernelLand/Modules/Filesystems/Ext2/ext2.c
index 971ef28e..f8f942d5 100644
--- a/KernelLand/Modules/Filesystems/Ext2/ext2.c
+++ b/KernelLand/Modules/Filesystems/Ext2/ext2.c
@@ -17,15 +17,16 @@ extern tVFS_NodeType	gExt2_DirType;
  int	Ext2_Install(char **Arguments);
  int	Ext2_Cleanup(void);
 // - Interface Functions
- int    	Ext2_Detect(int FD);
+ int    Ext2_Detect(int FD);
 tVFS_Node	*Ext2_InitDevice(const char *Device, const char **Options);
-void		Ext2_Unmount(tVFS_Node *Node);
-void		Ext2_CloseFile(tVFS_Node *Node);
+void	Ext2_Unmount(tVFS_Node *Node);
+void	Ext2_CloseFile(tVFS_Node *Node);
 // - Internal Helpers
- int		Ext2_int_GetInode(tVFS_Node *Node, tExt2_Inode *Inode);
-Uint64		Ext2_int_GetBlockAddr(tExt2_Disk *Disk, Uint32 *Blocks, int BlockNum);
-Uint32		Ext2_int_AllocateInode(tExt2_Disk *Disk, Uint32 Parent);
-void		Ext2_int_UpdateSuperblock(tExt2_Disk *Disk);
+ int	Ext2_int_GetInode(tVFS_Node *Node, tExt2_Inode *Inode);
+Uint64	Ext2_int_GetBlockAddr(tExt2_Disk *Disk, Uint32 *Blocks, int BlockNum);
+Uint32	Ext2_int_AllocateInode(tExt2_Disk *Disk, Uint32 Parent);
+void	Ext2_int_DereferenceInode(tExt2_Disk *Disk, Uint32 Inode);
+void	Ext2_int_UpdateSuperblock(tExt2_Disk *Disk);
 
 // === SEMI-GLOBALS ===
 MODULE_DEFINE(0, VERSION, FS_Ext2, Ext2_Install, Ext2_Cleanup);
@@ -208,7 +209,22 @@ void Ext2_Unmount(tVFS_Node *Node)
 void Ext2_CloseFile(tVFS_Node *Node)
 {
 	tExt2_Disk	*disk = Node->ImplPtr;
-	Inode_UncacheNode(disk->CacheID, Node->Inode);
+
+	if( Mutex_Acquire(&Node->Lock) != 0 )
+	{
+		return ;
+	}
+
+	if( Node->Flags & VFS_FFLAG_DIRTY )
+	{
+		// Commit changes
+	}
+
+	int was_not_referenced = (Node->ImplInt == 0);
+	if( Inode_UncacheNode(disk->CacheID, Node->Inode) && was_not_referenced )
+	{
+		// Remove inode
+	}
 	return ;
 }
 
@@ -337,6 +353,14 @@ Uint32 Ext2_int_AllocateInode(tExt2_Disk *Disk, Uint32 Parent)
 	return 0;
 }
 
+/**
+ * \brief Reduce the reference count on an inode
+ */
+void Ext2_int_DereferenceInode(tExt2_Disk *Disk, Uint32 Inode)
+{
+	
+}
+
 /**
  * \fn void Ext2_int_UpdateSuperblock(tExt2_Disk *Disk)
  * \brief Updates the superblock
diff --git a/KernelLand/Modules/Filesystems/Ext2/ext2_common.h b/KernelLand/Modules/Filesystems/Ext2/ext2_common.h
index 036cd59f..1d994ddb 100644
--- a/KernelLand/Modules/Filesystems/Ext2/ext2_common.h
+++ b/KernelLand/Modules/Filesystems/Ext2/ext2_common.h
@@ -32,6 +32,8 @@ typedef struct {
 extern void	Ext2_CloseFile(tVFS_Node *Node);
 extern Uint64	Ext2_int_GetBlockAddr(tExt2_Disk *Disk, Uint32 *Blocks, int BlockNum);
 extern void	Ext2_int_UpdateSuperblock(tExt2_Disk *Disk);
+extern Uint32	Ext2_int_AllocateInode(tExt2_Disk *Disk, Uint32 Parent);
+extern void	Ext2_int_DereferenceInode(tExt2_Disk *Disk, Uint32 Inode);
 extern int	Ext2_int_ReadInode(tExt2_Disk *Disk, Uint32 InodeId, tExt2_Inode *Inode);
 extern int	Ext2_int_WriteInode(tExt2_Disk *Disk, Uint32 InodeId, tExt2_Inode *Inode);
 // --- Dir ---
diff --git a/KernelLand/Modules/Filesystems/Ext2/write.c b/KernelLand/Modules/Filesystems/Ext2/write.c
index 60b176ca..22e256bf 100644
--- a/KernelLand/Modules/Filesystems/Ext2/write.c
+++ b/KernelLand/Modules/Filesystems/Ext2/write.c
@@ -119,7 +119,12 @@ addBlocks:
 	}
 	base = block * disk->BlockSize;
 	VFS_WriteAt(disk->FD, base, retLen, Buffer);
+	
+	// TODO: When should the size update be committed?
 	inode.i_size += retLen;
+	Node->Size += retLen;
+	Node->Flags |= VFS_FFLAG_DIRTY;
+	
 	retLen = 0;
 
 ret:	// Makes sure the changes to the inode are committed
-- 
2.20.1