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windows-nt/Source/XPSP1/NT/base/fs/fastfat/fatstruc.h

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/*++
Copyright (c) 1989-2000 Microsoft Corporation
Module Name:
FatStruc.h
Abstract:
This module defines the data structures that make up the major internal
part of the Fat file system.
// @@BEGIN_DDKSPLIT
Author:
Gary Kimura [GaryKi] 28-Dec-1989
Revision History:
// @@END_DDKSPLIT
--*/
#ifndef _FATSTRUC_
#define _FATSTRUC_
typedef PVOID PBCB; //**** Bcb's are now part of the cache module
//
// The FAT_DATA record is the top record in the Fat file system in-memory
// data structure. This structure must be allocated from non-paged pool.
//
typedef struct _FAT_DATA {
//
// The type and size of this record (must be FAT_NTC_DATA_HEADER)
//
NODE_TYPE_CODE NodeTypeCode;
NODE_BYTE_SIZE NodeByteSize;
PVOID LazyWriteThread;
//
// A queue of all the devices that are mounted by the file system.
//
LIST_ENTRY VcbQueue;
//
// A pointer to the Driver object we were initialized with
//
PDRIVER_OBJECT DriverObject;
//
// A pointer to the filesystem device objects we created.
//
PVOID DiskFileSystemDeviceObject;
PVOID CdromFileSystemDeviceObject;
//
// A resource variable to control access to the global Fat data record
//
ERESOURCE Resource;
//
// A pointer to our EPROCESS struct, which is a required input to the
// Cache Management subsystem.
//
PEPROCESS OurProcess;
//
// The following tells us if we should use Chicago extensions.
//
BOOLEAN ChicagoMode:1;
//
// The following field tells us if we are running on a Fujitsu
// FMR Series. These machines supports extra formats on the
// FAT file system.
//
BOOLEAN FujitsuFMR:1;
//
// Inidicates that FspClose is currently processing closes.
//
BOOLEAN AsyncCloseActive:1;
//
// The following BOOLEAN says shutdown has started on FAT. It
// instructs FspClose to not keep the Vcb resources anymore.
//
BOOLEAN ShutdownStarted:1;
//
// The following flag tells us if we are going to generate LFNs
// for valid 8.3 names with extended characters.
//
BOOLEAN CodePageInvariant:1;
//
// The following flags tell us if we are in an aggresive push to lower
// the size of the deferred close queues.
//
BOOLEAN HighAsync:1;
BOOLEAN HighDelayed:1;
//
// The following list entry is used for performing closes that can't
// be done in the context of the original caller.
//
ULONG AsyncCloseCount;
LIST_ENTRY AsyncCloseList;
//
// The following two fields record if we are delaying a close.
//
ULONG DelayedCloseCount;
LIST_ENTRY DelayedCloseList;
//
// This is the ExWorkerItem that does both kinds of deferred closes.
//
PIO_WORKITEM FatCloseItem;
//
// This spinlock protects several rapid-fire operations. NOTE: this is
// pretty horrible style.
//
KSPIN_LOCK GeneralSpinLock;
//
// Cache manager call back structures, which must be passed on each call
// to CcInitializeCacheMap.
//
CACHE_MANAGER_CALLBACKS CacheManagerCallbacks;
CACHE_MANAGER_CALLBACKS CacheManagerNoOpCallbacks;
} FAT_DATA;
typedef FAT_DATA *PFAT_DATA;
//
// An array of these structures will keep
typedef struct _FAT_WINDOW {
ULONG FirstCluster; // The first cluster in this window.
ULONG LastCluster; // The last cluster in this window.
ULONG ClustersFree; // The number of clusters free in this window.
} FAT_WINDOW;
typedef FAT_WINDOW *PFAT_WINDOW;
//
// The Vcb (Volume control Block) record corresponds to every volume mounted
// by the file system. They are ordered in a queue off of FatData.VcbQueue.
// This structure must be allocated from non-paged pool
//
typedef enum _VCB_CONDITION {
VcbGood = 1,
VcbNotMounted,
VcbBad
} VCB_CONDITION;
typedef struct _VCB {
//
// This is a common head for the FAT volume file
//
FSRTL_ADVANCED_FCB_HEADER VolumeFileHeader;
//
// The links for the device queue off of FatData.VcbQueue
//
LIST_ENTRY VcbLinks;
//
// A pointer the device object passed in by the I/O system on a mount
// This is the target device object that the file system talks to when it
// needs to do any I/O (e.g., the disk stripper device object).
//
//
PDEVICE_OBJECT TargetDeviceObject;
//
// A pointer to the VPB for the volume passed in by the I/O system on
// a mount.
//
PVPB Vpb;
//
// The internal state of the device. This is a collection of fsd device
// state flags.
//
ULONG VcbState;
VCB_CONDITION VcbCondition;
//
// A pointer to the root DCB for this volume
//
struct _FCB *RootDcb;
//
// If the FAT has so many entries that the free cluster bitmap would
// be too large, we split the FAT into buckets, and only one bucket's
// worth of bits are kept in the bitmap.
//
ULONG NumberOfWindows;
PFAT_WINDOW Windows;
PFAT_WINDOW CurrentWindow;
//
// A count of the number of file objects that have opened the volume
// for direct access, and their share access state.
//
CLONG DirectAccessOpenCount;
SHARE_ACCESS ShareAccess;
//
// A count of the number of file objects that have any file/directory
// opened on this volume, not including direct access. And also the
// count of the number of file objects that have a file opened for
// only read access (i.e., they cannot be modifying the disk).
//
CLONG OpenFileCount;
CLONG ReadOnlyCount;
//
// The bios parameter block field contains
// an unpacked copy of the bpb for the volume, it is initialized
// during mount time and can be read by everyone else after that.
//
BIOS_PARAMETER_BLOCK Bpb;
PUCHAR First0x24BytesOfBootSector;
//
// The following structure contains information useful to the
// allocation support routines. Many of them are computed from
// elements of the Bpb, but are too involved to recompute every time
// they are needed.
//
struct {
LBO RootDirectoryLbo; // Lbo of beginning of root directory
LBO FileAreaLbo; // Lbo of beginning of file area
ULONG RootDirectorySize; // size of root directory in bytes
ULONG NumberOfClusters; // total number of clusters on the volume
ULONG NumberOfFreeClusters; // number of free clusters on the volume
UCHAR FatIndexBitSize; // indicates if 12, 16, or 32 bit fat table
UCHAR LogOfBytesPerSector; // Log(Bios->BytesPerSector)
UCHAR LogOfBytesPerCluster; // Log(Bios->SectorsPerCluster)
} AllocationSupport;
//
// The following Mcb is used to keep track of dirty sectors in the Fat.
// Runs of holes denote clean sectors while runs of LBO == VBO denote
// dirty sectors. The VBOs are that of the volume file, starting at
// 0. The granuality of dirt is one sectors, and additions are only
// made in sector chunks to prevent problems with several simultaneous
// updaters.
//
LARGE_MCB DirtyFatMcb;
//
// The FreeClusterBitMap keeps track of all the clusters in the fat.
// A 1 means occupied while a 0 means free. It allows quick location
// of contiguous runs of free clusters. It is initialized on mount
// or verify.
//
RTL_BITMAP FreeClusterBitMap;
//
// The following fast mutex controls access to the free cluster bit map
// and the buckets.
//
FAST_MUTEX FreeClusterBitMapMutex;
//
// A resource variable to control access to the volume specific data
// structures
//
ERESOURCE Resource;
//
// A resource to make sure no one changes the volume bitmap while
// you're using it. Only for volumes with NumberOfWindows > 1.
//
ERESOURCE ChangeBitMapResource;
//
// The following field points to the file object used to do I/O to
// the virtual volume file. The virtual volume file maps sectors
// 0 through the end of fat and is of a fixed size (determined during
// mount)
//
PFILE_OBJECT VirtualVolumeFile;
//
// The following field contains a record of special pointers used by
// MM and Cache to manipluate section objects. Note that the values
// are set outside of the file system. However the file system on an
// open/create will set the file object's SectionObject field to point
// to this field
//
SECTION_OBJECT_POINTERS SectionObjectPointers;
//
// The following fields is a hint cluster index used by the file system
// when allocating a new cluster.
//
ULONG ClusterHint;
//
// This field contains the "DeviceObject" that this volume is
// currently mounted on. Note Vcb->Vpb->RealDevice is constant.
//
PDEVICE_OBJECT CurrentDevice;
//
// This is a pointer to the file object and the Fcb which represent the ea data.
//
PFILE_OBJECT VirtualEaFile;
struct _FCB *EaFcb;
//
// The following field is a pointer to the file object that has the
// volume locked. if the VcbState has the locked flag set.
//
PFILE_OBJECT FileObjectWithVcbLocked;
//
// The following is the head of a list of notify Irps.
//
LIST_ENTRY DirNotifyList;
//
// The following is used to synchronize the dir notify list.
//
PNOTIFY_SYNC NotifySync;
//
// The following fast mutex is used to synchronize directory stream
// file object creation.
//
FAST_MUTEX DirectoryFileCreationMutex;
//
// This field holds the thread address of the current (or most recent
// depending on VcbState) thread doing a verify operation on this volume.
//
PKTHREAD VerifyThread;
//
// The following two structures are used for CleanVolume callbacks.
//
KDPC CleanVolumeDpc;
KTIMER CleanVolumeTimer;
//
// This field records the last time FatMarkVolumeDirty was called, and
// avoids excessive calls to push the CleanVolume forward in time.
//
LARGE_INTEGER LastFatMarkVolumeDirtyCall;
//
// The following fields holds a pointer to a struct which is used to
// hold performance counters.
//
struct _FILE_SYSTEM_STATISTICS *Statistics;
//
// The property tunneling cache for this volume
//
TUNNEL Tunnel;
//
// The media change count is returned by IOCTL_CHECK_VERIFY and
// is used to verify that no user-mode app has swallowed a media change
// notification. This is only meaningful for removable media.
//
ULONG ChangeCount;
//
// Preallocated VPB for swapout, so we are not forced to consider
// must succeed pool.
//
PVPB SwapVpb;
//
// Per volume threading of the close queues.
//
LIST_ENTRY AsyncCloseList;
LIST_ENTRY DelayedCloseList;
//
// Fast mutex used by the ADVANCED FCB HEADER in this structure
//
FAST_MUTEX AdvancedFcbHeaderMutex;
} VCB;
typedef VCB *PVCB;
#define VCB_STATE_FLAG_LOCKED (0x00000001)
#define VCB_STATE_FLAG_REMOVABLE_MEDIA (0x00000002)
#define VCB_STATE_FLAG_VOLUME_DIRTY (0x00000004)
#define VCB_STATE_FLAG_MOUNTED_DIRTY (0x00000010)
#define VCB_STATE_FLAG_SHUTDOWN (0x00000040)
#define VCB_STATE_FLAG_CLOSE_IN_PROGRESS (0x00000080)
#define VCB_STATE_FLAG_DELETED_FCB (0x00000100)
#define VCB_STATE_FLAG_CREATE_IN_PROGRESS (0x00000200)
#define VCB_STATE_FLAG_BOOT_OR_PAGING_FILE (0x00000800)
#define VCB_STATE_FLAG_DEFERRED_FLUSH (0x00001000)
#define VCB_STATE_FLAG_ASYNC_CLOSE_ACTIVE (0x00002000)
#define VCB_STATE_FLAG_WRITE_PROTECTED (0x00004000)
#define VCB_STATE_FLAG_REMOVAL_PREVENTED (0x00008000)
#define VCB_STATE_FLAG_VOLUME_DISMOUNTED (0x00010000)
//
// N.B - VOLUME_DISMOUNTED is an indication that FSCTL_DISMOUNT volume was
// executed on a volume. It does not replace VcbCondition as an indication
// that the volume is invalid/unrecoverable.
//
//
// Define the file system statistics struct. Vcb->Statistics points to an
// array of these (one per processor) and they must be 64 byte aligned to
// prevent cache line tearing.
//
typedef struct _FILE_SYSTEM_STATISTICS {
//
// This contains the actual data.
//
FILESYSTEM_STATISTICS Common;
FAT_STATISTICS Fat;
//
// Pad this structure to a multiple of 64 bytes.
//
UCHAR Pad[64-(sizeof(FILESYSTEM_STATISTICS)+sizeof(FAT_STATISTICS))%64];
} FILE_SYSTEM_STATISTICS;
typedef FILE_SYSTEM_STATISTICS *PFILE_SYSTEM_STATISTICS;
//
// The Volume Device Object is an I/O system device object with a workqueue
// and an VCB record appended to the end. There are multiple of these
// records, one for every mounted volume, and are created during
// a volume mount operation. The work queue is for handling an overload of
// work requests to the volume.
//
typedef struct _VOLUME_DEVICE_OBJECT {
DEVICE_OBJECT DeviceObject;
//
// The following field tells how many requests for this volume have
// either been enqueued to ExWorker threads or are currently being
// serviced by ExWorker threads. If the number goes above
// a certain threshold, put the request on the overflow queue to be
// executed later.
//
ULONG PostedRequestCount;
//
// The following field indicates the number of IRP's waiting
// to be serviced in the overflow queue.
//
ULONG OverflowQueueCount;
//
// The following field contains the queue header of the overflow queue.
// The Overflow queue is a list of IRP's linked via the IRP's ListEntry
// field.
//
LIST_ENTRY OverflowQueue;
//
// The following spinlock protects access to all the above fields.
//
KSPIN_LOCK OverflowQueueSpinLock;
//
// This is a common head for the FAT volume file
//
FSRTL_COMMON_FCB_HEADER VolumeFileHeader;
//
// This is the file system specific volume control block.
//
VCB Vcb;
} VOLUME_DEVICE_OBJECT;
typedef VOLUME_DEVICE_OBJECT *PVOLUME_DEVICE_OBJECT;
//
// This is the structure used to contains the short name for a file
//
typedef struct _FILE_NAME_NODE {
//
// This points back to the Fcb for this file.
//
struct _FCB *Fcb;
//
// This is the name of this node.
//
union {
OEM_STRING Oem;
UNICODE_STRING Unicode;
} Name;
//
// Marker so we can figure out what kind of name we opened up in
// Fcb searches
//
BOOLEAN FileNameDos;
//
// And the links. Our parent Dcb has a pointer to the root entry.
//
RTL_SPLAY_LINKS Links;
} FILE_NAME_NODE;
typedef FILE_NAME_NODE *PFILE_NAME_NODE;
//
// This structure contains fields which must be in non-paged pool.
//
typedef struct _NON_PAGED_FCB {
//
// The following field contains a record of special pointers used by
// MM and Cache to manipluate section objects. Note that the values
// are set outside of the file system. However the file system on an
// open/create will set the file object's SectionObject field to point
// to this field
//
SECTION_OBJECT_POINTERS SectionObjectPointers;
//
// This context is non-zero only if the file currently has asynchronous
// non-cached valid data length extending writes. It allows
// synchronization between pending writes and other operations.
//
ULONG OutstandingAsyncWrites;
//
// This event is set when OutstandingAsyncWrites transitions to zero.
//
PKEVENT OutstandingAsyncEvent;
//
// This is the mutex that is inserted into the FCB_ADVANCED_HEADER
// FastMutex field
//
FAST_MUTEX AdvancedFcbHeaderMutex;
} NON_PAGED_FCB;
typedef NON_PAGED_FCB *PNON_PAGED_FCB;
//
// The Fcb/Dcb record corresponds to every open file and directory, and to
// every directory on an opened path. They are ordered in two queues, one
// queue contains every Fcb/Dcb record off of FatData.FcbQueue, the other
// queue contains only device specific records off of Vcb.VcbSpecificFcbQueue
//
typedef enum _FCB_CONDITION {
FcbGood = 1,
FcbBad,
FcbNeedsToBeVerified
} FCB_CONDITION;
typedef struct _FCB {
//
// The following field is used for fast I/O
//
// The following comments refer to the use of the AllocationSize field
// of the FsRtl-defined header to the nonpaged Fcb.
//
// For a directory when we create a Dcb we will not immediately
// initialize the cache map, instead we will postpone it until our first
// call to FatReadDirectoryFile or FatPrepareWriteDirectoryFile.
// At that time we will search the Fat to find out the current allocation
// size (by calling FatLookupFileAllocationSize) and then initialize the
// cache map to this allocation size.
//
// For a file when we create an Fcb we will not immediately initialize
// the cache map, instead we will postpone it until we need it and
// then we determine the allocation size from either searching the
// fat to determine the real file allocation, or from the allocation
// that we've just allocated if we're creating a file.
//
// A value of -1 indicates that we do not know what the current allocation
// size really is, and need to examine the fat to find it. A value
// of than -1 is the real file/directory allocation size.
//
// Whenever we need to extend the allocation size we call
// FatAddFileAllocation which (if we're really extending the allocation)
// will modify the Fat, Mcb, and update this field. The caller
// of FatAddFileAllocation is then responsible for altering the Cache
// map size.
//
// We are now using the ADVANCED fcb header to support filter contexts
// at the stream level
//
FSRTL_ADVANCED_FCB_HEADER Header;
//
// This structure contains fields which must be in non-paged pool.
//
PNON_PAGED_FCB NonPaged;
//
// The head of the fat alloaction chain. FirstClusterOfFile == 0
// means that the file has no current allocation.
//
ULONG FirstClusterOfFile;
//
// The links for the queue of all fcbs for a specific dcb off of
// Dcb.ParentDcbQueue. For the root directory this queue is empty
// For a non-existent fcb this queue is off of the non existent
// fcb queue entry in the vcb.
//
LIST_ENTRY ParentDcbLinks;
//
// A pointer to the Dcb that is the parent directory containing
// this fcb. If this record itself is the root dcb then this field
// is null.
//
struct _FCB *ParentDcb;
//
// A pointer to the Vcb containing this Fcb
//
PVCB Vcb;
//
// The internal state of the Fcb. This is a collection Fcb state flags.
// Also the shared access for each time this file/directory is opened.
//
ULONG FcbState;
FCB_CONDITION FcbCondition;
SHARE_ACCESS ShareAccess;
#ifdef SYSCACHE_COMPILE
//
// For syscache we keep a bitmask that tells us if we have dispatched IO for
// the page aligned chunks of the stream.
//
PULONG WriteMask;
ULONG WriteMaskData;
#endif
//
// A count of the number of file objects that have been opened for
// this file/directory, but not yet been cleaned up yet. This count
// is only used for data file objects, not for the Acl or Ea stream
// file objects. This count gets decremented in FatCommonCleanup,
// while the OpenCount below gets decremented in FatCommonClose.
//
CLONG UncleanCount;
//
// A count of the number of file objects that have opened
// this file/directory. For files & directories the FsContext of the
// file object points to this record.
//
CLONG OpenCount;
//
// A count of how many of "UncleanCount" handles were opened for
// non-cached I/O.
//
CLONG NonCachedUncleanCount;
//
// The following field is used to locate the dirent for this fcb/dcb.
// All directory are opened as mapped files so the only additional
// information we need to locate this dirent (beside its parent directory)
// is the byte offset for the dirent. Note that for the root dcb
// this field is not used.
//
VBO DirentOffsetWithinDirectory;
//
// The following field is filled in when there is an Lfn associated
// with this file. It is the STARTING offset of the Lfn.
//
VBO LfnOffsetWithinDirectory;
//
// Thess entries is kept in ssync with the dirent. It allows a more
// accurate verify capability and speeds up FatFastQueryBasicInfo().
//
LARGE_INTEGER CreationTime;
LARGE_INTEGER LastAccessTime;
LARGE_INTEGER LastWriteTime;
//
// Valid data to disk
//
ULONG ValidDataToDisk;
//
// The following field contains the retrieval mapping structure
// for the file/directory. Note that for the Root Dcb this
// structure is set at mount time. Also note that in this
// implementation of Fat the Mcb really maps VBOs to LBOs and not
// VBNs to LBNs.
//
LARGE_MCB Mcb;
//
// The following union is cased off of the node type code for the fcb.
// There is a seperate case for the directory versus file fcbs.
//
union {
//
// A Directory Control Block (Dcb)
//
struct {
//
// A queue of all the fcbs/dcbs that are opened under this
// Dcb.
//
LIST_ENTRY ParentDcbQueue;
//
// The following field points to the file object used to do I/O to
// the directory file for this dcb. The directory file maps the
// sectors for the directory. This field is initialized by
// CreateRootDcb but is left null by CreateDcb. It isn't
// until we try to read/write the directory file that we
// create the stream file object for non root dcbs.
//
ULONG DirectoryFileOpenCount;
PFILE_OBJECT DirectoryFile;
//
// If the UnusedDirentVbo is != 0xffffffff, then the dirent at this
// offset is guarenteed to unused. A value of 0xffffffff means
// it has yet to be initialized. Note that a value beyond the
// end of allocation means that there an unused dirent, but we
// will have to allocate another cluster to use it.
//
// DeletedDirentHint contains lowest possible VBO of a deleted
// dirent (assuming as above that it is not 0xffffffff).
//
VBO UnusedDirentVbo;
VBO DeletedDirentHint;
//
// The following two entries links together all the Fcbs
// opened under this Dcb sorted in a splay tree by name.
//
// I'd like to go into why we have (and must have) two separate
// splay trees within the current fastfat architecture. I will
// provide some insight into what would have to change if we
// wanted to have a single UNICODE tree.
//
// What makes FAT unique is that both Oem and Unicode names sit
// side by side on disk. Several unique UNICODE names coming
// into fastfat can match a single OEM on-disk name, and there
// is really no way to enumerate all the possible UNICODE
// source strings that can map to a given OEM name. This argues
// for converting the incomming UNICODE name into OEM, and then
// running through an OEM splay tree of the open files. This
// works well when there are only OEM names on disk.
//
// The UNICODE name on disk can be VERY different from the short
// name in the DIRENT and not even representable in the OEM code
// page. Even if it were representable in OEM, it is possible
// that a case varient of the original UNICODE name would match
// a different OEM name, causing us to miss the Fcb in the
// prefix lookup phase. In these cases, we must put UNICODE
// name in the splay to guarentee that we find any case varient
// of the input UNICODE name. See the routine description of
// FatConstructNamesInFcb() for a detailed analysis of how we
// detect this case.
//
// The fundamental limitation we are imposing here is that if
// an Fcb exists for an open file, we MUST find it during the
// prefix stage. This is a basic premise of the create path
// in fastfat. In fact if we later find it gravelling through
// the disk (but not the splay tree), we will bug check if we
// try to add a duplicate entry to the splay tree (not to
// mention having two Fcbs). If we had some mechanism to deal
// with cases (and they would be rare) that we don't find the
// entry in the splay tree, but the Fcb is actually in there,
// then we could go to a single UNICODE splay tree. While
// this uses more pool for the splay tree, and makes string
// compares maybe take a bit as longer, it would eliminate the
// need for any NLS conversion during the prefix phase, so it
// might really be a net win.
//
// The current scheme was optimized for non-extended names
// (i.e. US names). As soon as you start using extended
// characters, then it is clearly a win as many code paths
// become active that would otherwise not be needed if we
// only had a single UNICODE splay tree.
//
// We may think about changing this someday.
//
PRTL_SPLAY_LINKS RootOemNode;
PRTL_SPLAY_LINKS RootUnicodeNode;
//
// The following field keeps track of free dirents, i.e.,
// dirents that are either unallocated for deleted.
//
RTL_BITMAP FreeDirentBitmap;
//
// Since the FCB specific part of this union is larger, use
// the slack here for an initial bitmap buffer. Currently
// there is enough space here for an 8K cluster.
//
ULONG FreeDirentBitmapBuffer[1];
} Dcb;
//
// A File Control Block (Fcb)
//
struct {
//
// The following field is used by the filelock module
// to maintain current byte range locking information.
//
FILE_LOCK FileLock;
//
// The following field is used by the oplock module
// to maintain current oplock information.
//
OPLOCK Oplock;
//
// This pointer is used to detect writes that eminated in the
// cache manager's lazywriter. It prevents lazy writer threads,
// who already have the Fcb shared, from trying to acquire it
// exclusive, and thus causing a deadlock.
//
PVOID LazyWriteThread;
} Fcb;
} Specific;
//
// The following field is used to verify that the Ea's for a file
// have not changed between calls to query for Ea's. It is compared
// with a similar field in a Ccb.
//
// IMPORTANT!! **** DO NOT MOVE THIS FIELD ****
//
// The slack space in the union above is computed from
// the field offset of the EaModificationCount.
//
ULONG EaModificationCount;
//
// The following field is the fully qualified file name for this FCB/DCB
// starting from the root of the volume, and last file name in the
// fully qualified name.
//
FILE_NAME_NODE ShortName;
//
// The following field is only filled in if it is needed with the user's
// opened path
//
UNICODE_STRING FullFileName;
USHORT FinalNameLength;
//
// To make life simpler we also keep in the Fcb/Dcb a current copy of
// the fat attribute byte for the file/directory. This field must
// also be updated when we create the Fcb, modify the File, or verify
// the Fcb
//
UCHAR DirentFatFlags;
//
// The case preserved long filename
//
UNICODE_STRING ExactCaseLongName;
//
// If the UNICODE Lfn is fully expressible in the system Oem code
// page, then we will store it in a prefix table, otherwise we will
// store the last UNICODE name in the Fcb. In both cases the name
// has been upcased.
//
// Note that we may need neither of these fields if an LFN was strict
// 8.3 or differed only in case. Indeed if there wasn't an LFN, we
// don't need them at all.
//
union {
//
// This first field is present if FCB_STATE_HAS_OEM_LONG_NAME
// is set in the FcbState.
//
FILE_NAME_NODE Oem;
//
// This first field is present if FCB_STATE_HAS_UNICODE_LONG_NAME
// is set in the FcbState.
//
FILE_NAME_NODE Unicode;
} LongName;
//
// Defragmentation / ReallocateOnWrite synchronization object. This
// is filled in by FatMoveFile() and affects the read and write paths.
//
PKEVENT MoveFileEvent;
} FCB, *PFCB;
#ifndef BUILDING_FSKDEXT
//
// DCB clashes with a type defined outside the filesystems, in headers
// pulled in by FSKD. We don't need this typedef for fskd anyway....
//
typedef FCB DCB;
typedef DCB *PDCB;
#endif
//
// Here are the Fcb state fields.
//
#define FCB_STATE_DELETE_ON_CLOSE (0x00000001)
#define FCB_STATE_TRUNCATE_ON_CLOSE (0x00000002)
#define FCB_STATE_PAGING_FILE (0x00000004)
#define FCB_STATE_FORCE_MISS_IN_PROGRESS (0x00000008)
#define FCB_STATE_FLUSH_FAT (0x00000010)
#define FCB_STATE_TEMPORARY (0x00000020)
#define FCB_STATE_SYSTEM_FILE (0x00000080)
#define FCB_STATE_NAMES_IN_SPLAY_TREE (0x00000100)
#define FCB_STATE_HAS_OEM_LONG_NAME (0x00000200)
#define FCB_STATE_HAS_UNICODE_LONG_NAME (0x00000400)
#define FCB_STATE_DELAY_CLOSE (0x00000800)
//
// Copies of the dirent's FAT_DIRENT_NT_BYTE_* flags for
// preserving case of the short name of a file
//
#define FCB_STATE_8_LOWER_CASE (0x00001000)
#define FCB_STATE_3_LOWER_CASE (0x00002000)
//
// This is the slack allocation in the Dcb part of the UNION above
//
#define DCB_UNION_SLACK_SPACE ((ULONG) \
(FIELD_OFFSET(DCB, EaModificationCount) - \
FIELD_OFFSET(DCB, Specific.Dcb.FreeDirentBitmapBuffer)) \
)
//
// This is the special (64bit) allocation size that indicates the
// real size must be retrieved from disk. Define it here so we
// avoid excessive magic numbering around the driver.
//
#define FCB_LOOKUP_ALLOCATIONSIZE_HINT ((LONGLONG) -1)
//
// The Ccb record is allocated for every file object. Note that this
// record is exactly 0x34 long on x86 so that it will fit into a 0x40
// piece of pool. Please carefully consider modifications.
//
// Define the Flags field.
//
#define CCB_FLAG_MATCH_ALL (0x0001)
#define CCB_FLAG_SKIP_SHORT_NAME_COMPARE (0x0002)
//
// This tells us whether we allocated buffers to hold search templates.
//
#define CCB_FLAG_FREE_OEM_BEST_FIT (0x0004)
#define CCB_FLAG_FREE_UNICODE (0x0008)
//
// These flags prevents cleanup from updating the modify time, etc.
//
#define CCB_FLAG_USER_SET_LAST_WRITE (0x0010)
#define CCB_FLAG_USER_SET_LAST_ACCESS (0x0020)
#define CCB_FLAG_USER_SET_CREATION (0x0040)
//
// This bit says the file object associated with this Ccb was opened for
// read only access.
//
#define CCB_FLAG_READ_ONLY (0x0080)
//
// These flags, are used is DASD handles in read and write.
//
#define CCB_FLAG_DASD_FLUSH_DONE (0x0100)
#define CCB_FLAG_DASD_PURGE_DONE (0x0200)
//
// This flag keeps track of a handle that was opened for
// DELETE_ON_CLOSE.
//
#define CCB_FLAG_DELETE_ON_CLOSE (0x0400)
//
// This flag keeps track of which side of the name pair on the file
// associated with the handle was opened
//
#define CCB_FLAG_OPENED_BY_SHORTNAME (0x0800)
//
// This flag indicates that the query template has not been upcased
// (i.e., query should be case-insensitive)
//
#define CCB_FLAG_QUERY_TEMPLATE_MIXED (0x1000)
//
// This flag indicates that reads and writes via this DASD handle
// are allowed to start or extend past the end of file.
//
#define CCB_FLAG_ALLOW_EXTENDED_DASD_IO (0x2000)
//
// This flag indicates we want to match volume labels in directory
// searches (important for the root dir defrag).
//
#define CCB_FLAG_MATCH_VOLUME_ID (0x4000)
//
// This flag indicates the ccb has been converted over into a
// close context for asynchronous/delayed closing of the handle.
//
#define CCB_FLAG_CLOSE_CONTEXT (0x8000)
//
// This flag indicates that when the handle is closed, we want
// a physical dismount to occur.
//
#define CCB_FLAG_COMPLETE_DISMOUNT (0x10000)
//
// This flag indicates the handle may not call priveleged
// FSCTL which modify the volume.
//
#define CCB_FLAG_MANAGE_VOLUME_ACCESS (0x20000)
//
// This structure is used to keep track of information needed to do a
// deferred close. It is now embedded in a CCB so we don't have to
// allocate one in the close path (with mustsucceed).
//
typedef struct _CLOSE_CONTEXT {
//
// Two sets of links, one for the global list and one for closes
// on a particular volume.
//
LIST_ENTRY GlobalLinks;
LIST_ENTRY VcbLinks;
PVCB Vcb;
PFCB Fcb;
enum _TYPE_OF_OPEN TypeOfOpen;
BOOLEAN Free;
} CLOSE_CONTEXT;
typedef CLOSE_CONTEXT *PCLOSE_CONTEXT;
typedef struct _CCB {
//
// Type and size of this record (must be FAT_NTC_CCB)
//
NODE_TYPE_CODE NodeTypeCode;
NODE_BYTE_SIZE NodeByteSize;
//
// Define a 24bit wide field for Flags, but a UCHAR for Wild Cards Present
// since it is used so often. Line these up on byte boundaries for grins.
//
ULONG Flags:24;
BOOLEAN ContainsWildCards;
//
// Overlay a close context on the data of the CCB. The remaining
// fields are not useful during close, and we would like to avoid
// paying extra pool for it.
//
union {
struct {
//
// Save the offset to start search from.
//
VBO OffsetToStartSearchFrom;
//
// The query template is used to filter directory query requests.
// It originally is set to null and on the first call the NtQueryDirectory
// it is set to the input filename or "*" if the name is not supplied.
// All subsquent queries then use this template.
//
// The Oem structure are unions because if the name is wild we store
// the arbitrary length string, while if the name is constant we store
// 8.3 representation for fast comparison.
//
union {
//
// If the template contains a wild card use this.
//
OEM_STRING Wild;
//
// If the name is constant, use this part.
//
FAT8DOT3 Constant;
} OemQueryTemplate;
UNICODE_STRING UnicodeQueryTemplate;
//
// The field is compared with the similar field in the Fcb to determine
// if the Ea's for a file have been modified.
//
ULONG EaModificationCount;
//
// The following field is used as an offset into the Eas for a
// particular file. This will be the offset for the next
// Ea to return. A value of 0xffffffff indicates that the
// Ea's are exhausted.
//
ULONG OffsetOfNextEaToReturn;
};
CLOSE_CONTEXT CloseContext;
};
} CCB;
typedef CCB *PCCB;
//
// The Irp Context record is allocated for every orginating Irp. It is
// created by the Fsd dispatch routines, and deallocated by the FatComplete
// request routine. It contains a structure called of type REPINNED_BCBS
// which is used to retain pinned bcbs needed to handle abnormal termination
// unwinding.
//
#define REPINNED_BCBS_ARRAY_SIZE (4)
typedef struct _REPINNED_BCBS {
//
// A pointer to the next structure contains additional repinned bcbs
//
struct _REPINNED_BCBS *Next;
//
// A fixed size array of pinned bcbs. Whenever a new bcb is added to
// the repinned bcb structure it is added to this array. If the
// array is already full then another repinned bcb structure is allocated
// and pointed to with Next.
//
PBCB Bcb[ REPINNED_BCBS_ARRAY_SIZE ];
} REPINNED_BCBS;
typedef REPINNED_BCBS *PREPINNED_BCBS;
typedef struct _IRP_CONTEXT {
//
// Type and size of this record (must be FAT_NTC_IRP_CONTEXT)
//
NODE_TYPE_CODE NodeTypeCode;
NODE_BYTE_SIZE NodeByteSize;
//
// This structure is used for posting to the Ex worker threads.
//
WORK_QUEUE_ITEM WorkQueueItem;
//
// A pointer to the originating Irp.
//
PIRP OriginatingIrp;
//
// Originating Device (required for workque algorithms)
//
PDEVICE_OBJECT RealDevice;
//
// Originating Vcb (required for exception handling)
// On mounts, this will be set before any exceptions
// indicating corruption can be thrown.
//
PVCB Vcb;
//
// Major and minor function codes copied from the Irp
//
UCHAR MajorFunction;
UCHAR MinorFunction;
//
// The following fields indicate if we can wait/block for a resource
// or I/O, if we are to do everything write through, and if this
// entry into the Fsd is a recursive call.
//
UCHAR PinCount;
ULONG Flags;
//
// The following field contains the NTSTATUS value used when we are
// unwinding due to an exception
//
NTSTATUS ExceptionStatus;
//
// The following context block is used for non-cached Io
//
struct _FAT_IO_CONTEXT *FatIoContext;
//
// For a abnormal termination unwinding this field contains the Bcbs
// that are kept pinned until the Irp is completed.
//
REPINNED_BCBS Repinned;
} IRP_CONTEXT;
typedef IRP_CONTEXT *PIRP_CONTEXT;
#define IRP_CONTEXT_FLAG_DISABLE_DIRTY (0x00000001)
#define IRP_CONTEXT_FLAG_WAIT (0x00000002)
#define IRP_CONTEXT_FLAG_WRITE_THROUGH (0x00000004)
#define IRP_CONTEXT_FLAG_DISABLE_WRITE_THROUGH (0x00000008)
#define IRP_CONTEXT_FLAG_RECURSIVE_CALL (0x00000010)
#define IRP_CONTEXT_FLAG_DISABLE_POPUPS (0x00000020)
#define IRP_CONTEXT_FLAG_DEFERRED_WRITE (0x00000040)
#define IRP_CONTEXT_FLAG_VERIFY_READ (0x00000080)
#define IRP_CONTEXT_STACK_IO_CONTEXT (0x00000100)
#define IRP_CONTEXT_FLAG_IN_FSP (0x00000200)
#define IRP_CONTEXT_FLAG_USER_IO (0x00000400) // for performance counters
#define IRP_CONTEXT_FLAG_DISABLE_RAISE (0x00000800)
#define IRP_CONTEXT_FLAG_PARENT_BY_CHILD (0x80000000)
//
// Context structure for non-cached I/O calls. Most of these fields
// are actually only required for the Read/Write Multiple routines, but
// the caller must allocate one as a local variable anyway before knowing
// whether there are multiple requests are not. Therefore, a single
// structure is used for simplicity.
//
typedef struct _FAT_IO_CONTEXT {
//
// These two field are used for multiple run Io
//
LONG IrpCount;
PIRP MasterIrp;
//
// MDL to describe partial sector zeroing
//
PMDL ZeroMdl;
union {
//
// This element handles the asychronous non-cached Io
//
struct {
PERESOURCE Resource;
PERESOURCE Resource2;
ERESOURCE_THREAD ResourceThreadId;
ULONG RequestedByteCount;
PFILE_OBJECT FileObject;
PNON_PAGED_FCB NonPagedFcb;
} Async;
//
// and this element the sycnrhonous non-cached Io
//
KEVENT SyncEvent;
} Wait;
} FAT_IO_CONTEXT;
typedef FAT_IO_CONTEXT *PFAT_IO_CONTEXT;
//
// An array of these structures is passed to FatMultipleAsync describing
// a set of runs to execute in parallel.
//
typedef struct _IO_RUNS {
LBO Lbo;
VBO Vbo;
ULONG Offset;
ULONG ByteCount;
PIRP SavedIrp;
} IO_RUN;
typedef IO_RUN *PIO_RUN;
//
// This structure is used by FatDeleteDirent to preserve the first cluster
// and file size info for undelete utilities.
//
typedef struct _DELETE_CONTEXT {
ULONG FileSize;
ULONG FirstClusterOfFile;
} DELETE_CONTEXT;
typedef DELETE_CONTEXT *PDELETE_CONTEXT;
//
// This record is used with to set a flush to go off one second after the
// first write on slow devices with a physical indication of activity, like
// a floppy. This is an attempt to keep the red light on.
//
typedef struct _DEFERRED_FLUSH_CONTEXT {
KDPC Dpc;
KTIMER Timer;
WORK_QUEUE_ITEM Item;
PFILE_OBJECT File;
} DEFERRED_FLUSH_CONTEXT;
typedef DEFERRED_FLUSH_CONTEXT *PDEFERRED_FLUSH_CONTEXT;
//
// This structure is used for the FatMarkVolumeClean callbacks.
//
typedef struct _CLEAN_AND_DIRTY_VOLUME_PACKET {
WORK_QUEUE_ITEM Item;
PIRP Irp;
PVCB Vcb;
PKEVENT Event;
} CLEAN_AND_DIRTY_VOLUME_PACKET, *PCLEAN_AND_DIRTY_VOLUME_PACKET;
//
// This structure is used when a page fault is running out of stack.
//
typedef struct _PAGING_FILE_OVERFLOW_PACKET {
PIRP Irp;
PFCB Fcb;
} PAGING_FILE_OVERFLOW_PACKET, *PPAGING_FILE_OVERFLOW_PACKET;
//
// This structure is used to access the EaFile.
//
#define EA_BCB_ARRAY_SIZE 8
typedef struct _EA_RANGE {
PCHAR Data;
ULONG StartingVbo;
ULONG Length;
USHORT BcbChainLength;
BOOLEAN AuxilaryBuffer;
PBCB *BcbChain;
PBCB BcbArray[EA_BCB_ARRAY_SIZE];
} EA_RANGE, *PEA_RANGE;
#define EA_RANGE_HEADER_SIZE (FIELD_OFFSET( EA_RANGE, BcbArray ))
//
// These symbols are used by the upcase/downcase routines.
//
#define WIDE_LATIN_CAPITAL_A (0xff21)
#define WIDE_LATIN_CAPITAL_Z (0xff3a)
#define WIDE_LATIN_SMALL_A (0xff41)
#define WIDE_LATIN_SMALL_Z (0xff5a)
//
// These values are returned by FatInterpretClusterType.
//
typedef enum _CLUSTER_TYPE {
FatClusterAvailable,
FatClusterReserved,
FatClusterBad,
FatClusterLast,
FatClusterNext
} CLUSTER_TYPE;
#endif // _FATSTRUC_
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