>>>>> "Ted" == Ted Ts'o <tytso@xxxxxxx> writes: >> That saves the drive vendors from implementing RMW logic and puts the >> burden on us. Perfect deal. Ted> So it there a reliable way to detect that disk drives that don't Ted> have the Read-Modify-Write logic? If that can be reflected up the Ted> I/O layer I can have mke2fs enforce that restriction, which Ted> currently we only enforce if the logical blocksize is 4k. Not really :( I am aware of a few devices that report 512/512 but actually reject anything that's not an aligned multiple of 4KB. At least this Toshiba drive reports the physical block size correctly. The problem with detection is that we typically just get an I/O error. No explanation. The standards body dogma is that a storage device can abort any command at any time for any reason. Maybe a smoke test for mkfs would be to attempt to write a single logical block. If that gives an -EIO then attempt the physical block size instead. That assumes that the partition is aligned, but that should be taken care of with the latest tooling. -- Martin K. Petersen Oracle Linux Engineering -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
