From 59b806f4193cbda2da7aa6a1c004cd19de5e33bd Mon Sep 17 00:00:00 2001
From: John Hodge <tpg@mutabah.net>
Date: Mon, 11 Jul 2011 21:29:57 +0800
Subject: [PATCH] Kernel - VFS mmap spec (Node level)

---
 Kernel/include/vfs.h | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/Kernel/include/vfs.h b/Kernel/include/vfs.h
index f13f1b69..248a1ac9 100644
--- a/Kernel/include/vfs.h
+++ b/Kernel/include/vfs.h
@@ -67,6 +67,15 @@ typedef struct sVFS_SelectList	tVFS_SelectList;
  * inherit the GID of the parent.
  */
 #define VFS_FFLAG_SETGID	0x10
+
+/**
+ * \brief "Don't do Write-Back" Flag
+ *
+ * Stops the VFS from calling tVFS_Node.Write on dirty pages when a region
+ * is unmapped. Nice for read-only files and memory-only files (or 
+ * pseudo-readonly filesystems)
+ */
+#define VFS_FFLAG_NOWRITEBACK
 /**
  * \}
  */
@@ -215,6 +224,17 @@ typedef struct sVFS_Node
 	 * \return Number of bytes read
 	 */
 	Uint64	(*Write)(struct sVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer);
+
+	/**
+	 * \brief Map a region of a file into memory
+	 * \param Node	Pointer to this node
+	 * \param Offset	Start of the region (page aligned)
+	 * \param Length	Length of the region (page aligned)
+	 * \param Dest	Location to which to map
+	 * \return Boolean Failure
+	 * \note If NULL, the VFS implements it using .Read
+	 */
+	 int	(*MMap)(struct sVFS_Node *Node, Uint64 Offset, int Length, void *Dest);
 	
 	/**
 	 * \}
-- 
2.20.1