ftape-ecc.h
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- #ifndef _FTAPE_ECC_H_
- #define _FTAPE_ECC_H_
- /*
- * Copyright (C) 1993 Ning and David Mosberger.
- * Original:
- * Copyright (C) 1993 Bas Laarhoven.
- * Copyright (C) 1992 David L. Brown, Jr.
-
- This program is free software; you can redistribute it and/or
- modify it under the terms of the GNU General Public License as
- published by the Free Software Foundation; either version 2, or (at
- your option) any later version.
-
- This program is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program; see the file COPYING. If not, write to
- the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
- USA.
-
- *
- * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-ecc.h,v $
- * $Revision: 1.2 $
- * $Date: 1997/10/05 19:18:11 $
- *
- * This file contains the definitions for the
- * Reed-Solomon error correction code
- * for the QIC-40/80 tape streamer device driver.
- */
- #include "../lowlevel/ftape-bsm.h"
- #define BAD_CLEAR(entry) ((entry)=0)
- #define BAD_SET(entry,sector) ((entry)|=(1<<(sector)))
- #define BAD_CHECK(entry,sector) ((entry)&(1<<(sector)))
- /*
- * Return values for ecc_correct_data:
- */
- enum {
- ECC_OK, /* Data was correct. */
- ECC_CORRECTED, /* Correctable error in data. */
- ECC_FAILED, /* Could not correct data. */
- };
- /*
- * Representation of an in memory segment. MARKED_BAD lists the
- * sectors that were marked bad during formatting. If the N-th sector
- * in a segment is marked bad, bit 1<<N will be set in MARKED_BAD.
- * The sectors should be read in from the disk and packed, as if the
- * bad sectors were not there, and the segment just contained fewer
- * sectors. READ_SECTORS is a bitmap of errors encountered while
- * reading the data. These offsets are relative to the packed data.
- * BLOCKS is a count of the sectors not marked bad. This is just to
- * prevent having to count the zero bits in MARKED_BAD each time this
- * is needed. DATA is the actual sector packed data from (or to) the
- * tape.
- */
- struct memory_segment {
- SectorMap marked_bad;
- SectorMap read_bad;
- int blocks;
- __u8 *data;
- SectorMap corrected;
- };
- /*
- * ecc.c defined global variables:
- */
- #ifdef TEST
- extern int ftape_ecc_tracing;
- #endif
- /*
- * ecc.c defined global functions:
- */
- extern int ftape_ecc_correct_data(struct memory_segment *data);
- extern int ftape_ecc_set_segment_parity(struct memory_segment *data);
- #endif /* _FTAPE_ECC_H_ */