On Wed, Feb 08 2012 at 6:12pm -0500, Martin K. Petersen <martin.petersen@xxxxxxxxxx> wrote: > >>>>> "Mike" == Mike Snitzer <snitzer@xxxxxxxxxx> writes: > > >> + BUG_ON(length != bdev_logical_block_size(bdev)); > > Mike> Why require @length to be passed in if we can easily determine the > Mike> only correct length, via bdev_logical_block_size, locally? > > Just sanity checking since the caller is passing in a buffer pointer. > See my comment in the patch series introduction about a page vs a > buffer. I don't really care whether we pick one or the other. Whatever > makes the most sense to dm, md and the filesystems... OK, I see -- might make sense to use a page. But I don't have a strong opinion (and not sure I will have one in the near-term). I wrote a patch for dm-kcopyd (and dm-io) to add support for WRITE_SAME, but it doesn't use the new blkdev_* interfaces you've provided -- only because I needed to wire it up to dm-thinp which uses dm_kcopyd_zero() to provide async zeroing. So the patch open codes a small portion of bio prep code from blkdev_issue_write_same() in dm-io's do_region(). I'll post it once I verify it works. Mike -- 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
