diskio.c

T-kernel 的extension源代码

					MAP_FSTSK, mid, fsinfo);
	setSyncAtExit(SAE_FSTSK, fsinfo);

	return (DfFileHeaderBlock*)mapadr;

err_ret:
	DEBUG_PRINT(("fmpMapFileHeader err = %d\n", *mid));
	return NULL;
}

/* ======================================================================== */

/*
 * File system format and endian check
 *	Normal return value (>=0)
 *	bit 0 (LSB)  -  15	File system format
 *	bit 16			Endian format (1 when big endian)
 *	bit 17  -  31 (MSB)	Always 0.
 *	Return value when the format is abnormal.
 *	E_ILFMT
 */
EXPORT WER fmCheckDiskFormat( DfSystemHeader *sh )
{
	W	diskform = E_ILFMT;

	if ( (sh->fsid == StdfsDiskMagic)
	  || (sh->fsid == StdfsDiskMagic_E) ) {
		switch ( sh->diskid ) {
		  case StdfsDiskID_A:		/* STDFS standard format */
		  case StdfsDiskID_A2:		/* STDFS standard format (HD) */
			diskform = TSD_FCD_SFT_MC1 | DiskForm_A;
			break;
		  case StdfsDiskID_B:		/* STDFS extended format 1 */
			diskform = TSD_FCD_SFT_MC1 | DiskForm_B;
			break;
		  case StdfsDiskID_C:		/* STDFS extended format 2 */
			diskform = TSD_FCD_SFT_MC1 | DiskForm_C;
			break;
		  default:
			/* nothing to do */
			break;
		}
	}

	if ( (sh->fsid == swapH(StdfsDiskMagic))
	  || (sh->fsid == swapH(StdfsDiskMagic_E)) ) {
		switch ( swapH(sh->diskid) ) {
		  case StdfsDiskID_A:		/* STDFS standard format */
		  case StdfsDiskID_A2:		/* STDFS standard format (HD) */
			diskform = TSD_FCD_SFT_MC2 | DiskForm_A;
			break;
		  case StdfsDiskID_B:		/* STDFS extended format 1 */
			diskform = TSD_FCD_SFT_MC2 | DiskForm_B;
			break;
		  case StdfsDiskID_C:		/* STDFS extended format 2 */
			diskform = TSD_FCD_SFT_MC2 | DiskForm_C;
			break;
		  default:
			/* nothing to do */
			break;
		}
	}

	return diskform;
}

/*
 * Disk mapping (for common section task)
 */
LOCAL VP fmcMapPhyBlks( PhyBlk padr[], DiskMapInfo *dmInfo, ID_ERR *mid )
{
	MapMode		mode = FmTskMapMode;
	ER		err;

	mode.info = (VW)MAP_FMTSK;

	*mid = err = MapDisk(dmInfo->dskid, padr, &mode);
	if ( err < E_OK ) {
		if ( err == E_TMOUT ) {
			*mid = E_SYSMEM;
		}
		DEBUG_PRINT(("fmcMapPhyBlks err = %d\n", err));
		return NULL;
	}

	return mode.addr;
}

/*
 * Map the one logical block.
 */
LOCAL VP fmcMapLogBlk( UW lblk, W sblk, DiskMapInfo *dmInfo, ID_ERR *mid )
{
	PhyBlk		pblk[TSD_DIO_BLK_2];
	W		blkRatio;

	blkRatio = sblk / dmInfo->dskInfo.blocksize;

	pblk[0].blk = (lblk * (UW)blkRatio) + (UW)dmInfo->pbadj;
	pblk[0].len = (UW)blkRatio;
	pblk[1].len = 0;

	return fmcMapPhyBlks(pblk, dmInfo, mid);
}

/*
 * Find the file system header and set the DiskMapInfo.
 */
LOCAL ER fmcScanFileSystemHeader( DiskMapInfo *dmInfo, PhyBlk pblk[TSD_DIO_BLK_2] )
{
	static const UW	bootsz[] = StdBootBlkSizeList;
#define	N_BOOTSZ	( sizeof(bootsz)/sizeof(UW) )

	DfSystemHeader	*sh = NULL;
	ID		mid;
	W		i;
	FsSpec		fsspec;
	ER		err;

	/*
	 * Retrieve the boot block size.
	 *	Try several sizes.
	 */
	for ( i = 0; i < (W)N_BOOTSZ; ++i ) {
		if ( (UW)dmInfo->dskInfo.blocksize > bootsz[i] ) {
			continue;
		}

		/* Location of the system header */
		pblk[0].blk = bootsz[i] / (UW)dmInfo->dskInfo.blocksize;
		pblk[0].len = ((sizeof(DfSystemHeader) - 1)
					/ (UW)dmInfo->dskInfo.blocksize) + 1;
		pblk[1].len = 0;

		/* Map the system header. */
		sh = fmcMapPhyBlks(pblk, dmInfo, &mid);
		if ( sh == NULL ) {
			err = (ER)mid;
			goto err_ret;
		}

		/* Check the disk format. */
		err = fmCheckDiskFormat(sh);
		if ( err >= 0 ) {
			/* OK: Set the file system format and endian format. */
			dmInfo->diskform = DiskFormVersion(err);
			dmInfo->big      = DiskFormEndian(err);
			break;
		}

		(void)fmcUnmapDisk(mid, MD_RDONLY);
	}
	if ( i >= (W)N_BOOTSZ ) {
		err = E_ILFMT;
		goto err_ret;
	}

	/* Correction value for computing the physical block number
	   Correction value when the boot block size and logical block size are not equal. */
	dmInfo->pbadj =
		((W)bootsz[i] - (W)fmConvEndianH(sh->sblk, dmInfo->big))
						/ dmInfo->dskInfo.blocksize;
#if !MisalignLogBlk
	if ( dmInfo->pbadj != 0 ) {
		(void)fmcUnmapDisk(mid, MD_RDONLY);
		err = E_ILFMT;
		goto err_ret;
	}
#endif

	/* Notify the segment management of the file system information. */
	fsspec.lbsz = fmConvEndianH(sh->sblk, dmInfo->big);
	fsspec.btsz = (UH)bootsz[i];
	(void)fmcUnmapDisk(mid, MD_RDONLY);
	err = InformFS(dmInfo->dskid, &fsspec);
	if ( err < E_OK ) {
		if ( err == E_BUSY ) {
			err = E_SYS;
		}
		goto err_ret;
	}

	return E_OK;

err_ret:
	DEBUG_PRINT(("fmcScanFileSystemHeader err = %d\n", err));
	return err;
}

/*
 * Map the file system header.
 *	Check also the disk format when the file system is not connected.
 */
EXPORT DfSystemHeader* fmcMapFileSystemHeader( DiskMapInfo *dmInfo,
						FsInfo *fsinfo, ID_ERR *mid )
{
	PhyBlk		pblk[TSD_DIO_BLK_2];
	DfSystemHeader	*sh;
	ER		err;

	if ( fsinfo == NULL ) {
		/* The file system is not connected. */
		err = fmcScanFileSystemHeader(dmInfo, pblk);
		if ( err < E_OK ) {
			goto err_ret;
		}
	} else {
		/* The file system has already connected. */
		dmInfo->big = fsinfo->bigEndian;
		dmInfo->pbadj = fsinfo->pbadj;

		/* Location of the system header */
		pblk[0].blk = fsinfo->blkRatio + (UW)dmInfo->pbadj;
		pblk[0].len = ((sizeof(DfSystemHeader) - 1U)
					/ (UW)dmInfo->dskInfo.blocksize) + 1U;
		pblk[1].len = 0;
	}

	/* Map the file system header. */
	sh = fmcMapPhyBlks(pblk, dmInfo, mid);
	if ( sh == NULL ) {
		err = (ER)*mid;
		goto err_ret;
	}

	return sh;

err_ret:
	DEBUG_PRINT(("fmcMapFileSystemHeader err = %d\n", err));
	*mid = err;
	return NULL;
}

/*
 * Map the root file header.
 */
EXPORT DfFileHeader* fmcMapRootFileHeader( DfSystemHeader *sh,
					DiskMapInfo *dmInfo, ID_ERR *mid )
{
	W		ssys, sblk;
	DfFileID	*fidt, f;
	DfFileHeader	*fh;
	ER		err;

	/* Logical block size */
	sblk = (W)fmConvEndianH(sh->sblk, dmInfo->big);

	/* System block size */
	ssys = (W)fmConvEndianH(sh->ssys, dmInfo->big);

	/* Map the file ID table. */
	fidt = fmcMapLogBlk((UW)(ssys + 1), sblk, dmInfo, mid);
	if ( fidt == NULL ) {
		err = (ER)*mid;
		goto err_ret;
	}

	/* Obtain the file header block address. */
	f = fmConvEndianFileID(*fidt, dmInfo->big);

	err = fmcUnmapDisk(*mid, MD_RDONLY);
	if ( err < E_OK ) {
		goto err_ret;
	}

	/* Map the file header. */
	fh = fmcMapLogBlk(f.s.blkadr, sblk, dmInfo, mid);
	if ( fh == NULL ) {
		err = (ER)*mid;
		goto err_ret;
	}

	return fh;

err_ret:
	DEBUG_PRINT(("fmcMapRootFileHeader err = %d\n", err));
	*mid = err;
	return NULL;
}

/*
 * Map the root file abbreviated name.
 */
EXPORT DfShortName* fmcMapRootFileShortName( DfSystemHeader *sh,
					DiskMapInfo *dmInfo, ID_ERR *mid )
{
	W		sblk, ssys, sfidt;
	DfShortName	*sfnt;
	ER		err;

	/* Logical block size */
	sblk = (W)fmConvEndianH(sh->sblk, dmInfo->big);

	/* System block size */
	ssys = (W)fmConvEndianH(sh->ssys, dmInfo->big);

	/* File ID table size */
	sfidt = (W)fmConvEndianH(sh->sfidt, dmInfo->big);

	/* Map the first one block of the file abbreviated name table. */
	sfnt = fmcMapLogBlk((UW)(ssys + sfidt + 1), sblk, dmInfo, mid);
	if ( sfnt == NULL ) {
		err = (ER)*mid;
		goto err_ret;
	}

	return sfnt;

err_ret:
	DEBUG_PRINT(("fmcMapRootFileShortName err = %d\n", err));
	*mid = err;
	return NULL;
}

/* ======================================================================== */

#if !USE_DEVICE_MANAGER
LOCAL UB devname[L_DEVNM + 1];
#endif

/*
 * Check the disk partition information.
 */
EXPORT ER fmCheckPartitionID( DevName devnm )
{
	DiskPartInfo	info;
	W		dd, asz;
	ER		err, chk;

#if USE_DEVICE_MANAGER
	dd = tkse_opn_dev2(devnm, D_READ, NULL);
	if ( dd < E_OK ) {
		err = dd;
		goto err_ret1;
	}

	err = tkse_rea_dev2(dd, DN_DISKPARTINFO, (B*)&info, sizeof(info),
							&asz, NULL);
	if ( err < E_OK ) {
		if ( !((err == E_NOSPT) || (err == E_PAR)) ) {
			goto err_ret2;
		}
		chk = E_OK;
	} else {
		chk = isSTDFS_SID(info.systemid)? E_OK: E_ILFMT;
	}

	err = tkse_cls_dev2(dd, 0, NULL);
	if ( err < E_OK ) {
		goto err_ret1;
	}
#else
	/* Convert the device name. TC -> ASCII */
	if ( tcstoeucs(NULL, devnm) > L_DEVNM
	  || tcstoeucs(devname, devnm) < 0 ) {
		err = E_PAR;
		goto err_ret1;
	}

	/* Disk connection */
	dd = tk_opn_dev(devname, TD_READ);
	if ( dd < E_OK ) {
		err = ERtoERR(dd);
		goto err_ret1;
	}

	/* Obtain the disk information. */
	err = tk_srea_dev(dd, DN_DISKPARTINFO, (B*)&info,
			  sizeof(info), &asz);
	if ( err < E_OK ) {
		err = ERtoERR(err);
		if ( !((err == E_NOSPT) || (err == E_PAR)) ) {
			goto err_ret2;
		}
		chk = E_OK;
	} else {
		chk = isSTDFS_SID(info.systemid)? E_OK: E_ILFMT;
	}

	err = tk_cls_dev(dd, 0);
	if ( err < E_OK ) {
		err = ERtoERR(err);
		goto err_ret1;
	}
#endif

	return chk;

err_ret2:
#if USE_DEVICE_MANAGER
	(void)tkse_cls_dev2(dd, 0, NULL);
#else
	(void)tk_cls_dev(dd, 0);
#endif
err_ret1:
	DEBUG_PRINT(("fmCheckPartitionID err = %d\n", err));
	return err;
}