@@ -796,14 +796,27 @@ VirtioScsiInit (
// We must be able to halve it for bidirectional transfers
// (see EFI_BAD_BUFFER_SIZE in PopulateRequest()).
//
Status = EFI_UNSUPPORTED;
goto Failed;
}
+ Features &= VIRTIO_SCSI_F_INOUT | VIRTIO_F_VERSION_1;
+
+ //
+ // In virtio-1.0, feature negotiation is expected to complete before queue
+ // discovery, and the device can also reject the selected set of features.
+ //
+ if (Dev->VirtIo->Revision >= VIRTIO_SPEC_REVISION (1, 0, 0)) {
+ Status = Virtio10WriteFeatures (Dev->VirtIo, Features, &NextDevStat);
+ if (EFI_ERROR (Status)) {
+ goto Failed;
+ }
+ }
+
//
// step 4b -- allocate request virtqueue
//
Status = Dev->VirtIo->SetQueueSel (Dev->VirtIo, VIRTIO_SCSI_REQUEST_QUEUE);
if (EFI_ERROR (Status)) {
goto Failed;
}
@@ -843,22 +856,22 @@ VirtioScsiInit (
//
Status = Dev->VirtIo->SetQueueAddress (Dev->VirtIo, &Dev->Ring);
if (EFI_ERROR (Status)) {
goto ReleaseQueue;
}
//
- // step 5 -- Report understood features and guest-tuneables. We want none of
- // the known (or unknown) VIRTIO_SCSI_F_* or VIRTIO_F_* capabilities (see
- // virtio-0.9.5, Appendices B and I), except bidirectional transfers.
+ // step 5 -- Report understood features and guest-tuneables.
//
- Status = Dev->VirtIo->SetGuestFeatures (Dev->VirtIo,
- Features & VIRTIO_SCSI_F_INOUT);
- if (EFI_ERROR (Status)) {
- goto ReleaseQueue;
+ if (Dev->VirtIo->Revision < VIRTIO_SPEC_REVISION (1, 0, 0)) {
+ Features &= ~(UINT64)VIRTIO_F_VERSION_1;
+ Status = Dev->VirtIo->SetGuestFeatures (Dev->VirtIo, Features);
+ if (EFI_ERROR (Status)) {
+ goto ReleaseQueue;
+ }
}
//
// We expect these maximum sizes from the host. Since they are
// guest-negotiable, ask for them rather than just checking them.
//
Status = VIRTIO_CFG_WRITE (Dev, CdbSize, VIRTIO_SCSI_CDB_SIZE);
Relative to virtio-0.9.5, virtio-1.0 reverses the order of queue discovery and feature negotiation. In virtio-1.0, feature negotiation has to complete first, and the device can also reject a self-inconsistent feature request through the new VSTAT_FEATURES_OK status bit. (For example if the driver requests a higher level feature but clears a prerequisite feature.) Furthermore, we retain the VIRTIO_F_VERSION_1 feature bit if the VIRTIO_DEVICE_PROTOCOL provider has high enough revision. Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Jordan Justen <jordan.l.justen@intel.com> Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Laszlo Ersek <lersek@redhat.com> --- OvmfPkg/VirtioScsiDxe/VirtioScsi.c | 27 +++++++++++++++----- 1 file changed, 20 insertions(+), 7 deletions(-) -- 1.8.3.1 _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel