Kernel - Implementing SysSpawn

[tpg/acess2.git] / Kernel / include / vfs.h

diff --git a/Kernel/include/vfs.h b/Kernel/include/vfs.h
index cded047..1aa073b 100644 (file)
--- a/Kernel/include/vfs.h
+++ b/Kernel/include/vfs.h
@@ -26,6 +26,8 @@
  */
 typedef struct sVFS_SelectList tVFS_SelectList;
 
+typedef struct sVFS_NodeType   tVFS_NodeType;
+
 /**
  * \name tVFS_Node Flags
  * \brief Flag values for tVFS_Node.Flags
@@ -67,6 +69,15 @@ 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
 /**
  * \}
  */
@@ -85,7 +96,7 @@ typedef struct sVFS_Node
         *        corresponds to.
         * \{
         */
-       Uint64  Inode;  //!< Inode ID (Essentially another ImplInt)
+       Uint64  Inode;  //!< Inode ID - Must identify the node uniquely if tVFS_Driver.GetNodeFromINode is non-NULL
        Uint    ImplInt;        //!< Implementation Usable Integer
        void    *ImplPtr;       //!< Implementation Usable Pointer
        /**
@@ -146,6 +157,7 @@ typedef struct sVFS_Node
        
        /**
         * \name VFS_Select() fields
+        * \note Used by the VFS internals, drivers should use VFS_Mark*
         * \{
         */
         int    DataAvaliable;
@@ -157,7 +169,32 @@ typedef struct sVFS_Node
        /**
         * \}
         */
+
+       /**
+        * \name VFS_MMap() fields
+        * \{
+        */
+       void    *MMapInfo;
+       /**
+        * \}
+        */
        
+       /**
+        * \brief Functions associated with the node
+        */
+       tVFS_NodeType   *Type;
+} tVFS_Node;
+
+/**
+ * \brief Functions for a specific node type
+ */
+struct sVFS_NodeType
+{
+       /**
+        * \brief Debug name for the type
+        */
+       const char      *TypeName;
+
        /**
         * \name Common Functions
         * \brief Functions that are used no matter the value of .Flags
@@ -214,7 +251,18 @@ typedef struct sVFS_Node
         * \param Buffer        Source of written data
         * \return Number of bytes read
         */
-       Uint64  (*Write)(struct sVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer);
+       Uint64  (*Write)(struct sVFS_Node *Node, Uint64 Offset, Uint64 Length, const 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);
        
        /**
         * \}
@@ -269,30 +317,44 @@ typedef struct sVFS_Node
         * \param Node  Pointer to this node (directory)
         * \param Child Node to create a new link to
         * \param NewName       Name for the new link
-        * \return Zeron on success, non-zero on error (see errno.h)
+        * \retur Zeron on success, non-zero on error (see errno.h)
         */
         int    (*Link)(struct sVFS_Node *Node, struct sVFS_Node *Child, const char *NewName);
         
         /**
          * \}
          */
-} tVFS_Node;
+};
 
 /**
  * \brief VFS Driver (Filesystem) Definition
  */
 typedef struct sVFS_Driver
 {
-       //! \brief Unique Identifier for this filesystem type
+       /**
+        * \brief Unique Identifier for this filesystem type
+        */
        const char      *Name;
-       //! \brief Flags applying to this driver
+       /**
+        * \brief Flags applying to this driver
+        */
        Uint    Flags;
        
-       //! \brief Callback to mount a device
+       /**
+        * \brief Callback to mount a device
+        */
        tVFS_Node       *(*InitDevice)(const char *Device, const char **Options);
-       //! \brief Callback to unmount a device
+       /**
+        * \brief Callback to unmount a device
+        */
        void    (*Unmount)(tVFS_Node *Node);
-       //! \brief Used internally (next driver in the chain)
+       /**
+        * \brief Retrieve a VFS node from an inode
+        */
+       tVFS_Node       *(*GetNodeFromINode)(tVFS_Node *RootNode, Uint64 InodeValue);
+       /**
+        * \brief Used internally (next driver in the chain)
+        */
        struct sVFS_Driver      *Next;
 } tVFS_Driver;
 
@@ -326,7 +388,6 @@ extern tVFS_ACL     gVFS_ACL_EveryoneRO;    //!< Everyone Read only
  */
 extern int     VFS_AddDriver(tVFS_Driver *Info);
 /**
- * \fn tVFS_Driver *VFS_GetFSByName(char *Name)
  * \brief Get the information structure of a driver given its name
  * \param Name Name of filesystem driver to find
  */
@@ -356,13 +417,15 @@ extern void       VFS_CleanupNode(tVFS_Node *Node);
 extern tVFS_ACL        *VFS_UnixToAcessACL(Uint Mode, Uint Owner, Uint Group);
 
 /**
+ * \brief Flags fro \a TypeFlag of VFS_SelectNode
+ * \{
+ */
+#define VFS_SELECT_READ        0x01
+#define VFS_SELECT_WRITE       0x02
+#define VFS_SELECT_ERROR       0x04
+/**
+ * \}
  */
-enum eVFS_SelectTypes
-{
-       VFS_SELECT_READ,
-       VFS_SELECT_WRITE,
-       VFS_SELECT_ERROR
-};
 
 /**
  * \brief Wait for an event on a node
@@ -372,13 +435,19 @@ enum eVFS_SelectTypes
  * \param Name Name to show in debug output
  * \return Number of nodes that actioned (0 or 1)
  */
-extern int     VFS_SelectNode(tVFS_Node *Node, enum eVFS_SelectTypes Type, tTime *Timeout, const char *Name);
+extern int     VFS_SelectNode(tVFS_Node *Node, int Type, tTime *Timeout, const char *Name);
 
 /**
  * \brief Change the full flag on a node
  */
 extern int     VFS_MarkFull(tVFS_Node *Node, BOOL IsBufferFull);
+/**
+ * \brief Alter the space avaliable flag on a node
+ */
 extern int     VFS_MarkAvaliable(tVFS_Node *Node, BOOL IsDataAvaliable);
+/**
+ * \brief Alter the error flags on a node
+ */
 extern int     VFS_MarkError(tVFS_Node *Node, BOOL IsErrorState);
 
 // --- Node Cache --