>>>>> "Tom" == Tom Yan <tom.ty89@xxxxxxxxx> writes: Tom, >> put_unaligned_be64(65535 * ATA_MAX_TRIM_RNUM / (sector_size / 512), &rbuf[36]); How many 8-byte ranges fit in a 4096-byte sector? Tom> So were you trying to pointing out something I am still missing, or Tom> were you merely confirming I was right? I suggest you drop ATA_MAX_TRIM_RNUM and do: enum { ATA_TRIM_BLOCKS_PER_RANGE = 65535, /* 0xffff blocks per range desc. */ ATA_TRIM_RANGE_SIZE_SHIFT = 3, /* range descriptor is 8 bytes */ }; put_unaligned_be64(ATA_TRIM_BLOCKS_PER_RANGE * sector_size >> ATA_TRIM_RANGE_SIZE_SHIFT, &rbuf[36]); Might be worthwhile to create an ata_max_lba_range_blocks() wrapper. -- Martin K. Petersen Oracle Linux Engineering -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html