On Thu, Jul 25, 2024 at 06:45:36PM GMT, Wouter Verhelst wrote: > The NBD protocol defines the flag NBD_FLAG_ROTATIONAL to flag that the > export in use should be treated as a rotational device. > > Add support for that flag to the kernel driver. > > Signed-off-by: Wouter Verhelst <w@xxxxxxx> > --- > drivers/block/nbd.c | 3 +++ > include/uapi/linux/nbd.h | 3 ++- > 2 files changed, 5 insertions(+), 1 deletion(-) Reviewed-by: Eric Blake <eblake@xxxxxxxxxx> For what it's worth, the nbdkit project recently made it possible to aad a filter on top of any existing NBD server to change the setting of the rotational bit[1], as well as a filter to intentionally simulate delays of a rotational device[2], in order to experiment with how much impact changing the bit can have when it is not ignored. [1] https://libguestfs.org/nbdkit-rotational-filter.1.html [2] https://libguestfs.org/nbdkit-spinning-filter.1.html -- Eric Blake, Principal Software Engineer Red Hat, Inc. Virtualization: qemu.org | libguestfs.org
