On Wed, Oct 26, 2016 at 05:46:11PM -0400, Mikulas Patocka wrote: > I think the proper thing would be to move "discard_zeroes_data" flag into > the bio itself - there would be REQ_OP_DISCARD and REQ_OP_DISCARD_ZERO - > and if the device doesn't support REQ_OP_DISCARD_ZERO, it rejects the bio > and the caller is supposed to do zeroing manually.
Yes, Martin and I have come to a similar conclusion recently. An additional aspect is that NVMe has a Write Zeroes command which is more limited than what REQ_OP_WRITE_SAME does. So I think the right way is to add a REQ_OP_WRITE_ZEROES (or REQ_OP_ZERO) and have modifies if it may discard or not. -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel
