IBM TS2340 User Guide - Page 122

Linux Device Driver (lin_tape) Read SILI Bit SILI bit currently is not supported due to limitations associated with the Linux environment. SILI bit support may be enabled in future releases of the lin_tape. Record Space Mode This parameter specifies how the device driver operates when a forward or backward space record operation encounters a filemark. Only the SCSI mode is supported by lin_tape. When a forward or backward space record operation is issued to the driver and a filemark is encountered, the device driver returns -1 and the errno variable is set to input/output error (EIO). On the forward space operation, the tape is left-positioned after the filemark (the end of tape side of the filemark). On the backward space operation, the tape is positioned before the filemark (the beginning of tape side of the filemark). Volume ID for Logging This parameter is the volume ID of the currently loaded tape. The lin_tape device driver ignores this field. Write Protect This parameter is set to TRUE if the currently mounted tape is logically or physically write protected. Changeable Parameters The configuration parameters are used to set the operating mode of the tape drive and device driver when a device is opened. The changeable parameters are detailed as follows: Block Size This parameter specifies the block size used for read and write operations. A value of zero means a variable block size. Any other value is a fixed block size. The installation default is zero (variable length block size). Refer to "Maximum SCSI Transfer Length" on page 106 for additional guidance. Buffered Mode This parameter specifies if read and write operations should be buffered by the tape device. The default (recommended) value is TRUE. Capacity Scaling This parameter sets the capacity or logical length of the current tape on Enterprise Tape System 3590 or 3592 tape subsystems. By reducing the capacity of the tape, the tape drive can access data faster at the expense of data capacity. Capacity scaling can be set at 100% for the entire tape (which is the default), or set at 75%, 50%, or 25% of the 3590 tape cartridge and more available capacity scaling for the 3592 standard 300 GB rewritable data cartridge. Capacity scaling remains with the tape across mounts until it is changed. Note: 1. The tape position must be at the start of the tape to change this parameter from its current value. 2. Changing this parameter destroys any existing data on the tape. 3. For 3592 media types, capacity scaling is only supported for the standard 300 GB rewritable data cartridge. Attempting to set capacity scaling that is not supported by a device or the current media loaded always returns 100% and cannot be changed. For example, the 60GB (Economy Data) cartridge for the IBM 3592 cannot be capacity scaled and is always 100%. 104 IBM Tape Device Drivers Installation and User's Guide