>>>>> "Lukas" == Lukas Czerner <lczerner@xxxxxxxxxx> writes: Lukas> As Jeff Moyer pointed out we do not honor discard granularity Lukas> while submitting REQ_DISCARD bios of size smaller than Lukas> max_discard_sectors. That fact might have unwanted consequences Lukas> of device ignoring the request, or even worse if device firmware Lukas> is buggy. We've discussed this before and the consensus was not to do it. The granularity is a hint, not a hard limit like max_discard_sectors. We want the reporting to be comprehensive throughout the block layer. If we start aligning to the granularity at the top we lose information for stacked devices below with a finer granularity. So if we were to align to the granularity we'd want to do it at the bottom of the stack when we issue the command to the device. We've had a few proposed patches to did that but so far we've only found one device where it made a difference. And that case didn't justify adding a quirk. -- 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
