On Tue, 12 Jun 2018 13:18:00 +0800 Tiwei Bie <tiwei....@intel.com> wrote:
> Document the driver requirements for the VIRTIO_F_SR_IOV > feature bit. > > Suggested-by: Michael S. Tsirkin <m...@redhat.com> > Signed-off-by: Tiwei Bie <tiwei....@intel.com> > Fixes: https://github.com/oasis-tcs/virtio-spec/issues/13 > --- > v2: > - Fix the commit message (MST); > - Improve the wording (MST); > - Drop unnecessary parts (MST); > > v3: > - status -> device status (MST); > > content.tex | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/content.tex b/content.tex > index be18234..ab18210 100644 > --- a/content.tex > +++ b/content.tex > @@ -5387,6 +5387,21 @@ A driver SHOULD accept VIRTIO_F_IO_BARRIER if it is > offered. > If VIRTIO_F_IO_BARRIER has been negotiated, a driver MUST use > the barriers suitable for hardware devices. > > +If VIRTIO_F_SR_IOV has been negotiated, a driver MAY enable > +virtual functions through the device's PCI SR-IOV capability > +structure. A driver MUST NOT negotiate VIRTIO_F_SR_IOV if > +the device does not have a PCI SR-IOV capability structure > +or is not a PCI device. A driver MUST negotiate > +VIRTIO_F_SR_IOV and complete the feature negotiation > +(including checking the FEATURES_OK \field{device status} > +bit) before enabling virtual functions through the device's > +PCI SR-IOV capability structure. After once successfully > +negotiating VIRTIO_F_SR_IOV, the driver MAY enable virtual > +functions through the device's PCI SR-IOV capability > +structure even if the device or the system has been fully > +or partially reset, and even without re-negotiating > +VIRTIO_F_SR_IOV after the reset. > + > \devicenormative{\section}{Reserved Feature Bits}{Reserved Feature Bits} > > A device MUST offer VIRTIO_F_VERSION_1. A device MAY fail to operate further I still think we should mention somewhere that this "enable just once" mechanism is useful for e.g. resuming; but this is fine as-is. Reviewed-by: Cornelia Huck <coh...@redhat.com> --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscr...@lists.oasis-open.org For additional commands, e-mail: virtio-dev-h...@lists.oasis-open.org
