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Diffstat (limited to 'device/param.h')
| -rw-r--r-- | device/param.h | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/device/param.h b/device/param.h new file mode 100644 index 0000000..41b4793 --- /dev/null +++ b/device/param.h @@ -0,0 +1,49 @@ +/* + * Mach Operating System + * Copyright (c) 1991,1990 Carnegie Mellon University + * All Rights Reserved. + * + * Permission to use, copy, modify and distribute this software and its + * documentation is hereby granted, provided that both the copyright + * notice and this permission notice appear in all copies of the + * software, derivative works or modified versions, and any portions + * thereof, and that both notices appear in supporting documentation. + * + * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" + * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR + * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. + * + * Carnegie Mellon requests users of this software to return to + * + * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU + * School of Computer Science + * Carnegie Mellon University + * Pittsburgh PA 15213-3890 + * + * any improvements or extensions that they make and grant Carnegie Mellon + * the rights to redistribute these changes. + */ +/* + * Author: David B. Golub, Carnegie Mellon University + * Date: 7/90 + */ + +#ifndef _DEVICE_PARAM_H_ +#define _DEVICE_PARAM_H_ + +/* + * Compatibility definitions for disk IO. + */ + +/* + * Disk devices do all IO in 512-byte blocks. + */ +#define DEV_BSIZE 512 + +/* + * Conversion between bytes and disk blocks. + */ +#define btodb(byte_offset) ((byte_offset) >> 9) +#define dbtob(block_number) ((block_number) << 9) + +#endif /* _DEVICE_PARAM_H_ */ |