tfs.h

可移到ucos上的文件系统

/* tfs.h:
 *	Header file for TFS transactions.
 * 
 *	General notice:
 *	This code is part of a boot-monitor package developed as a generic base
 *	platform for embedded system designs.  As such, it is likely to be
 *	distributed to various projects beyond the control of the original
 *	author.  Please notify the author of any enhancements made or bugs found
 *	so that all may benefit from the changes.  In addition, notification back
 *	to the author will allow the new user to pick up changes that may have
 *	been made by other users after this version of the code was distributed.
 *
 *	Author:	Ed Sutter
 *	email:	[e-mail]		(home: [e-mail])
 *	phone:	[phone]			(home: 908-889-5161)
 */
#ifndef _tfs_h
#define _tfs_h

#define SANITY			0xBEEF
#define ERASED16		0xFFFF
#define ERASED32		0xFFFFFFFF
#define TFS_MAXOPEN		10		/* Maximum of 10 open files */
#define TFS_QRYTMOUT	100000	/* Timeout for QRYBRUN */
#define TFS_FSIZEMOD	16		/* File size must be a multiple of this value */
#define MINUSRLEVEL		0		/* Minimum user level supported. */
#define MAXUSRLEVEL		3		/* Maximum user level supported. */
#define TFSINFOSIZE		23		/* Max size of info string (mod4-1). */

#define TFSHDRVERSION	1		/* Increment this if TFS header changes. */

#ifndef TFSNAMESIZE				/* This specifies the maximum size of a file */
#define TFSNAMESIZE		23		/* name that can be used in TFS. */
#endif							/* This MUST be some value mod4 - 1. */

#ifndef TFS_AUTODEFRAG			/* Set to 1 typically, this allows tfsadd() */
#define TFS_AUTODEFRAG	1		/* to automatically do a defrag when it is  */
#endif							/* adding a file, but needs cleanup first.  */

#ifndef TFS_CHANGELOG_FILE		/* Information used for change-log */
#define TFS_CHANGELOG_SIZE	0	/* facility within tfs. */
#define TFS_CHANGELOG_FILE	".tfschlog"
#endif

#ifndef DEFRAG_TEST_ENABLED 	/* Enable testing for tfsclean() by		*/
#define DEFRAG_TEST_ENABLED 0	/* setting this flag to 1. */
#endif

/* NOTE that the "ifndef" macros above are provided as defaults.  If
 * there is a need to change any of them, do it in config.h 
 */

#if TFS_EBIN_COFF
#define TFS_EBIN_NAME	"coff"
#elif TFS_EBIN_AOUT
#define TFS_EBIN_NAME	"aout"
#elif TFS_EBIN_ELF
#define TFS_EBIN_NAME	"elf"
#else
#define TFS_EBIN_NAME	"NA"
#endif

/* Flags: */
#define TFS_EXEC	0x00000001	/* 'e': Executable script. */
#define TFS_BRUN	0x00000002	/* 'b': To be executed at boot. */
#define TFS_QRYBRUN	0x00000004	/* 'B': To be executed at boot if */
								/*      query passes. */
#define TFS_EBIN	0x00000010	/* 'E': Executable binary (coff/elf/a.out). */
#define TFS_CPRS	0x00000040	/* 'c': File is compressed. */
#define TFS_IPMOD	0x00000080	/* 'i': File is in-place modifiable. */
#define TFS_UNREAD	0x00000100	/* 'u':	File is not even readable if the */
								/*		user-level requirement is not met; */
								/*		else, it is read-only. */
#define TFS_ULVLMSK	0x00000600	/*	User level mask defines 4 access levels: */
#define TFS_ULVL0	0x00000000	/* '0'	level 0 */
#define TFS_ULVL1	0x00000200	/* '1'	level 1 */
#define TFS_ULVL2	0x00000400	/* '2'	level 2 */
#define TFS_ULVL3	0x00000600	/* '3'	level 3 */
#define TFS_NSTALE	0x00000800	/* File is NOT stale, invisible to user.
								 * When this bit is clear, the file is 
								 * considered stale (see notes in tfsadd()). 
								 * See notes in tfsclose() for this.
								 */
#define TFS_ACTIVE	0x00008000	/* Used to indicate that file is not deleted. */

#define TFS_ULVLMAX	TFS_ULVL3
#define TFS_USRLVL(f)	((f->flags & TFS_ULVLMSK) >> 9)

/* Open modes */
#define	TFS_RDONLY	0x00010000	/* File is opened for reading. */
#define	TFS_CREATE	0x00020000	/* File is to be created. */
#define	TFS_APPEND	0x00040000	/* Append to existing file or */
								/* create new file. */
#define	TFS_ALLFFS	0x00080000	/* File is created with all FFs. */

/* Masks used to allow flags and modes to be part of the same long word. */
#define TFS_FLAGMASK	0x0000ffff
#define TFS_MODEMASK	0xffff0000

/* Definitions used by the fixup algorithm. */
#define TFSFIXUPDONE		0x00000000
#define TFSFIXUPNA			0xFFFFFFFF

/* Requests that can be made to tfsctrl(): */
#define	TFS_ERRMSG		1
#define	TFS_MEMUSE		2
#define	TFS_MEMDEAD		3
#define	TFS_DEFRAG		4
#define	TFS_TELL		5
#define	TFS_UNOPEN		7
#define	TFS_FATOB		8
#define	TFS_FBTOA		9
#define	TFS_MEMAVAIL	10
#define	TFS_TIMEFUNCS	11
#define	TFS_DOCOMMAND	12
#define	TFS_INITDEV		13
#define	TFS_CHECKDEV	14
#define	TFS_DEFRAGDEV	15

/* Definitions related to tfslog: */
#define TFSLOG_ADD		0
#define TFSLOG_DEL		1
#define TFSLOG_IPM		2
#define TFSLOG_ON		3
#define TFSLOG_OFF		4
#define TIME_UNDEFINED	0xffffffff

/* Used by tfsscript.. */
#define EXIT_SCRIPT		1
#define REMOVE_SCRIPT	2

/* Macros used for partial-header-copy in defragmentation... */
#define TFS_PHCBITS			0xF0000000
#define TFS_PHCSTARTED		0xE0000000
#define TFS_PHCCOPIED		0xC0000000
#define TFS_PHCDONE			0x80000000
#define PHC_IS_STARTED(x)	((x & TFS_PHCBITS) == TFS_PHCSTARTED)
#define PHC_IS_COPIED(x)	((x & TFS_PHCBITS) == TFS_PHCCOPIED)
#define PHC_IS_DONE(x)		((x & TFS_PHCBITS) == TFS_PHCDONE)
#define GET_PHC_VALUE(x)	(x & ~TFS_PHCBITS)
#define SET_PHC_STARTED(x)	(GET_PHC_VALUE(x) | TFS_PHCSTARTED)
#define SET_PHC_COPIED(x)	(GET_PHC_VALUE(x) | TFS_PHCCOPIED)
#define SET_PHC_DONE(x)		(GET_PHC_VALUE(x) | TFS_PHCDONE)

/* struct tfshdr:
 *	It is in FLASH as part of the file system to record the attributes of
 *	the file at the time of creation.
 */
struct tfshdr {
	unsigned short	hdrsize;		/* Size of this header.					*/
	unsigned short	hdrvrsn;		/* Header version #.					*/
	long	filsize;				/* Size of the file.					*/
	long	flags;					/* Flags describing the file.			*/
	unsigned long filcrc; 			/* 32 bit CRC of file.					*/
	unsigned long hdrcrc;			/* 32 bit CRC of the header.			*/
	unsigned long	modtime;		/* Time when file was last modified.	*/
	struct	tfshdr	*next;			/* Pointer to next file in list.		*/
	char	name[TFSNAMESIZE+1];	/* Name of file.						*/
	char	info[TFSINFOSIZE+1];	/* Miscellaneous info field.			*/
};

#define TFSHDRSIZ	sizeof(struct tfshdr)

/* Device Table structure and definitions:
 *	The Device table is typically only one entry in length.  It is defined
 *	on a per-target basis in the file tfsdev.h.  In the simplest case, the
 *	table in tfsdev.h has all of the information in it.  This is fine as long
 *	as there is no need to support different devices with the same monitor
 *	binary.  To support the ability to have a device-table that is constructed
 *	based on the type of flash on-board, the TFS_DEVINFO_DYNAMIC bit must
 *	be set in the devinfo member of tfsdevtbl (in tfsdev.h).  This tells TFS
 *	to figure out the addresses based on a few assumptions...
 *	 * Regardless of the device type, the start address will be the same.
 *	 * The spare sector starts immediately after the end of TFS storage space.
 *	In dynamic mode, all that need be specified in the tfsdevtbl of tfsdev.h
 *	is the prefix, start and devinfo fields.  The other fields will be built
 *	based on information taken from the flash interface.
 *	One important note: if there is a block of contiguous flash space that
 *	spans accross multiple flash banks, then the bank # of the last bank in
 *	that block is what should be specified in the devinfo BANKMASK field.
 */

#define TFSEOT	0xffffffff
#define TDEV	struct tfsdev

#define TFS_DEVTYPE_RAM			0x00001000
#define TFS_DEVTYPE_FLASH		0x00002000
#define TFS_DEVTYPE_MASK		0x0000f000
#define TFS_DEVINFO_DYNAMIC		0x00000800
#define TFS_DEVINFO_BANKMASK	0x000007ff
#define TFSDEVTOT ((sizeof(tfsdevtbl))/(sizeof(struct tfsdev)))

struct tfsdev {
	char 			*prefix;		/* Device name prefix.					*/
	unsigned long	start;			/* First location into which TFS can	*/
									/* begin to store files.				*/
	unsigned long	end;			/* Last address into which TFS can		*/
									/* place file data.  This is usually	*/
									/* one unit below the start of the		*/
									/* spare sector.						*/
	unsigned long	spare;			/* Start address of device spare		*/
									/* sector.								*/
	unsigned long	sparesize;		/* Size of device spare sector.			*/
	unsigned long	sectorcount;	/* Number of sectors in this device.	*/
	unsigned long	devinfo;		/* RAM or FLASH, etc...					*/
};

/* TFS defragmentation process:
	Allocate the last (or first) sector to be dedicated as the SPARE sector.
	Save enough space at the end of file system space to support one
	defraghdr structure per valid file.  Plus about 128 bytes for keeping
	track of defragmentation state.

	1. Erase SPARE sector.
	2. Mark the end of the file system indicating that defragmentation
	   is in progress.
	3. Copy the standard headers of all non-deleted files to a table of
	   defraghdr structures that is placed at the end of the flash space
	   allocated to TFS (but not used by the spare sector).
	4. For (N=0;N<TFSSECTORS;N++) {
		a. copy sector[N] to SPARE