Moves the tape to the partition given by the argument at the next tape operation. The block at which the tape is positioned is the block where the tape was previously positioned in the new active partition unless the next tape operation is MTSEEK. Formats the tape with one partition argument zero or two partitions argument non-zero.
If the argument is positive, it specifies the size of partition 1 in megabytes. For DDS drives and several early drives this is the physically first partition of the tape. If the argument is negative, its absolute value specifies the size of partition 0 in megabytes. The drive has to support partitions with size specified by the initiator. Is used for several purposes. This command is only allowed for the superuser root. The subcommands are:.
Sets the buffering options. It is recommended to set this flag unless there are tapes using the device dependent from the old times global. Defines the default block size set automatically. Value 0xffffff means that the default is not used any more. Used to set or clear the density 8 bits , and drive buffer state 3 bits. Otherwise the lowermost bits of the value contain the new value of the parameter. The compression default will not be used if the value of the lowermost byte is 0xff.
Otherwise the lowermost bit contains the new default. If the bits are set to a non-zero number, and this number is not 0xff, the number is used as the compression algorithm. Set the normal timeout in seconds for this device. The default is seconds 15 minutes. Set the long timeout that is used for operations that are known to take a long time. The default is seconds 3. For erase this value is further multiplied by eight. Set the cleaning request interpretation parameters using the lowest 24 bits of the argument.
Many drives set one or more bits in the extended sense data when the drive needs cleaning. The bits are device-dependent. If the bit pattern is zero, one or more bits under the mask indicate cleaning request.
If the pattern is non-zero, the pattern must match the masked sense data byte. Reads the current position from the drive. Returns some status information. The file number and block number within file are returned. If more tapes are detected at driver initialization, the maximum is adjusted accordingly.
If this is defined, the user should take care that the next tape operation is not started before the previous one has finished. With this method the file number in the status is correct. In this case the file number will be invalid. Any ideas on how to restore the module loading at boot time? Thanks in advance for any insight!
That's part of 7. Use the FAQ Luke. Apparently not. Avij: Thanks for the link. This is definitely what I'm seeing and the solution is clearly stated in the release notes. Thanks again!
Guy Boisvert, ing. IngTegration inc. If so, we report that the command was reset. This will also inform the SCSI layer that the reset we reported as pending in our reset function has now completed. Next we check for errors. A real driver should check for as many errors as can be identified.
The SCSI layer will handle recovery from an error situation. Then we look to see if this interrupt is due to a SCSI phase change. SCSI commands pass through a set of phases during their lifetime. A smart controller handles all of these phases automatically, whereas a dumb controller usually needs some help from the driver.
SCSI commands can also be issued synchronously, through the command function, although this is rarely used. Supporting synchronous commands is best done in terms of the queuecommand function, shown by the code in Figure 6.
Having issued the command, we spin in a loop until the command finishes. The barrier statement is important here. This ensures that the status, which is changed by an interrupt, will be seen by the looping code. This completes the SCSI command handlers for our simple card. They are not optimized, and our card is a little simplistic. The info function in Figure 7 returns a text description for our controller. Thus we have to continue this fiction.
The example in Figure 8 is taken from the Symbios 53c driver and is quite typical. Given the disk size, we fill in an array of integers for the heads, sectors, and cylinders of our disk. We want to be sure that these are right. To unload the kernel module, we need to clean up our resources. We provide a release function for this [ see Figure 9 ]. To make our driver a SCSI module, we have to include some magic at the end of the file myscsi. It is defined in a separate file, as it is used for both kernel modules and drivers compiled into the kernel.
Our myscsi. In the lk 2. From lk 2. Can also output disk defect lists. Port of older scsiinfo utility. Newer ddpt utility adds features and is ported to "f,s,w".
With the '--set' option a new identifier is sent to the device. In lk 2. Also does mapping in to, and out of, sysfs. For the Linux 2.
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