>>>>> "Christoph" == Christoph Hellwig <hch@xxxxxxxxxxxxx> writes: >> Make the choice of checksum a per-I/O property by introducing a flag >> that can be inspected by the SCSI layer. Christoph> Why? First of all it's desirable to be able to use both IP and CRC checksums without having to unload the HBA driver. Also, there are some corner cases where you have to force the use of CRC guard tag even when the HBA supports IP checksums. If you are doing recovery and need to read a disk block with bad PI, for instance, you must be able to tell the HBA to pass the CRC through verbatim instead of attempting to convert it to IP checksum. Another example is qualification tooling that needs to be able to write a block with bad PI out to storage. In that case we also have to tell the HBA to ignore checking the PI and that it shouldn't attempt a checksum conversion. -- Martin K. Petersen Oracle Linux Engineering -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
