X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Finclude%2Fvfs.h;h=91771c8a6ebbe2bc0c477acbb9c4e3f03bc8114a;hb=dd2491a82880ed9b01b5d66b1814d271921797a4;hp=47cbe190f983c4ef03a2cc778120d756010d4d50;hpb=cf4418f1fcdd441e639d6b95afda42dd74db5f7c;p=tpg%2Facess2.git diff --git a/Kernel/include/vfs.h b/Kernel/include/vfs.h index 47cbe190..91771c8a 100644 --- a/Kernel/include/vfs.h +++ b/Kernel/include/vfs.h @@ -21,6 +21,11 @@ #include +/** + * \brief Thread list datatype for VFS_Select + */ +typedef struct sVFS_SelectList tVFS_SelectList; + /** * \name tVFS_Node Flags * \brief Flag values for tVFS_Node.Flags @@ -44,36 +49,86 @@ * Marks a file as a symbolic link */ #define VFS_FFLAG_SYMLINK 0x04 +/** + * \brief Set User ID Flag + * + * Allows an executable file to change it's executing user to the file's + * owner. + * In the case of a directory, it means that all immediate children will + * inherit the UID of the parent. + */ +#define VFS_FFLAG_SETUID 0x08 +/** + * \brief Set Group ID Flag + * + * Allows an executable file to change it's executing group to the file's + * owning group. + * In the case of a directory, it means that all immediate children will + * 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 /** * \} */ /** - * \brief VFS Node + * \brief Represents a node (file or directory) in the VFS tree * * This structure provides the VFS with the functions required to read/write * the file (or directory) that it represents. */ -typedef struct sVFS_Node { +typedef struct sVFS_Node +{ /** * \name Identifiers * \brief Fields used by the driver to identify what data this 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 /** * \} */ + /** + * \name Node State + * \brief Stores the misc information about the node + * \{ + */ int ReferenceCount; //!< Number of times the node is used Uint64 Size; //!< File Size Uint32 Flags; //!< File Flags + /** + * \brief Pointer to cached data (FS Specific) + * \note The Inode_* functions will free when the node is uncached + * this if needed + */ + void *Data; + + /** + * \brief Node mutex + * \note Provided for the Filesystem driver's use + */ + tMutex Lock; + + /** + * \} + */ + /** * \name Times * \{ @@ -86,7 +141,7 @@ typedef struct sVFS_Node { */ /** - * \name Access controll + * \name Access control * \{ */ tUID UID; //!< ID of Owning User @@ -98,6 +153,30 @@ typedef struct sVFS_Node { * \} */ + /** + * \name VFS_Select() fields + * \note Used by the VFS internals, drivers should use VFS_Mark* + * \{ + */ + int DataAvaliable; + tVFS_SelectList *ReadThreads; //!< Threads waiting to read + int BufferFull; + tVFS_SelectList *WriteThreads; //!< Threads waiting to write + int ErrorOccurred; + tVFS_SelectList *ErrorThreads; //!< Threads waiting for an error + /** + * \} + */ + + /** + * \name VFS_MMap() fields + * \{ + */ + void *MMapInfo; + /** + * \} + */ + /** * \name Common Functions * \brief Functions that are used no matter the value of .Flags @@ -127,7 +206,7 @@ typedef struct sVFS_Node { int (*IOCtl)(struct sVFS_Node *Node, int Id, void *Data); /** - * } + * \} */ /** @@ -155,9 +234,20 @@ 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); /** - * } + * \} */ /** @@ -172,7 +262,7 @@ typedef struct sVFS_Node { * \note The node returned must be accessable until ::tVFS_Node.Close * is called and ReferenceCount reaches zero. */ - struct sVFS_Node *(*FindDir)(struct sVFS_Node *Node, char *Name); + struct sVFS_Node *(*FindDir)(struct sVFS_Node *Node, const char *Name); /** * \brief Read from a directory @@ -191,21 +281,30 @@ typedef struct sVFS_Node { * \param Node Pointer to this node * \param Name Name of the new child * \param Flags Flags to apply to the new child (directory or symlink) - * \return Boolean success + * \return Zero on Success, non-zero on error (see errno.h) */ - int (*MkNod)(struct sVFS_Node *Node, char *Name, Uint Flags); + int (*MkNod)(struct sVFS_Node *Node, const char *Name, Uint Flags); /** * \brief Relink (Rename/Remove) a file/directory * \param Node Pointer to this node * \param OldName Name of the item to move/delete * \param NewName New name (or NULL if unlinking is wanted) - * \return Boolean Success + * \return Zero on Success, non-zero on error (see errno.h) + */ + int (*Relink)(struct sVFS_Node *Node, const char *OldName, const char *NewName); + + /** + * \brief Link a node to a name + * \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) */ - int (*Relink)(struct sVFS_Node *Node, char *OldName, char *NewName); + int (*Link)(struct sVFS_Node *Node, struct sVFS_Node *Child, const char *NewName); /** - * } + * \} */ } tVFS_Node; @@ -214,16 +313,30 @@ typedef struct sVFS_Node { */ typedef struct sVFS_Driver { - //! \brief Unique Identifier for this filesystem type - char *Name; - //! \brief Flags applying to this driver + /** + * \brief Unique Identifier for this filesystem type + */ + const char *Name; + /** + * \brief Flags applying to this driver + */ Uint Flags; - //! \brief Callback to mount a device - tVFS_Node *(*InitDevice)(char *Device, char **Options); - //! \brief Callback to unmount a device + /** + * \brief Callback to mount a device + */ + tVFS_Node *(*InitDevice)(const char *Device, const char **Options); + /** + * \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; @@ -257,11 +370,24 @@ 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 */ -extern tVFS_Driver *VFS_GetFSByName(char *Name); +extern tVFS_Driver *VFS_GetFSByName(const char *Name); + + +/** + * \brief Prepare a node for use + */ +extern void VFS_InitNode(tVFS_Node *Node); + +/** + * \brief Clean up a node, ready for deletion + * \note This should ALWAYS be called before a node is freed, as it + * cleans up VFS internal structures. + */ +extern void VFS_CleanupNode(tVFS_Node *Node); + /** * \fn tVFS_ACL *VFS_UnixToAcessACL(Uint Mode, Uint Owner, Uint Group) * \brief Transforms Unix Permssions into Acess ACLs @@ -272,6 +398,40 @@ extern tVFS_Driver *VFS_GetFSByName(char *Name); */ 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 +/** + * \} + */ + +/** + * \brief Wait for an event on a node + * \param Node Node to wait on + * \param Type Type of wait + * \param Timeout Time to wait (NULL for infinite wait) + * \param Name Name to show in debug output + * \return Number of nodes that actioned (0 or 1) + */ +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 -- /** * \name Node Cache @@ -283,11 +443,11 @@ extern tVFS_ACL *VFS_UnixToAcessACL(Uint Mode, Uint Owner, Uint Group); * \{ */ /** - * \fn int Inode_GetHandle() + * \fn int Inode_GetHandle(void) * \brief Gets a unique handle to the Node Cache * \return A unique handle for use for the rest of the Inode_* functions */ -extern int Inode_GetHandle(); +extern int Inode_GetHandle(void); /** * \fn tVFS_Node *Inode_GetCache(int Handle, Uint64 Inode) * \brief Gets an inode from the node cache @@ -305,7 +465,7 @@ extern tVFS_Node *Inode_GetCache(int Handle, Uint64 Inode); */ extern tVFS_Node *Inode_CacheNode(int Handle, tVFS_Node *Node); /** - * \fn void Inode_UncacheNode(int Handle, Uint64 Inode) + * \fn int Inode_UncacheNode(int Handle, Uint64 Inode) * \brief Dereferences (and removes if needed) a node from the cache * \param Handle A handle returned by Inode_GetHandle() * \param Inode Value of the Inode field of the ::tVFS_Node you want to remove