From 5df04f1762ef78c08fd69e19dcedf3d9ba8c9b86 Mon Sep 17 00:00:00 2001 From: Felipe Franciosi Date: Wed, 14 Jun 2017 18:44:38 +0100 Subject: vhost-user: fix legacy cross-endian configurations Currently, vhost-user does not implement any means for notifying the backend about guest endianess. This commit introduces a new message called VHOST_USER_SET_VRING_ENDIAN which is analogous to the ioctl() called VHOST_SET_VRING_ENDIAN used for kernel vhost backends. Such message is necessary for backends supporting legacy (pre-1.0) virtio devices running in big-endian guests. Signed-off-by: Felipe Franciosi Signed-off-by: Mike Cui --- hw/virtio/vhost-user.c | 23 +++++++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-) (limited to 'hw/virtio') diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c index 2203011125..093675ed98 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -33,6 +33,7 @@ enum VhostUserProtocolFeature { VHOST_USER_PROTOCOL_F_REPLY_ACK = 3, VHOST_USER_PROTOCOL_F_NET_MTU = 4, VHOST_USER_PROTOCOL_F_SLAVE_REQ = 5, + VHOST_USER_PROTOCOL_F_CROSS_ENDIAN = 6, VHOST_USER_PROTOCOL_F_MAX }; @@ -63,6 +64,7 @@ typedef enum VhostUserRequest { VHOST_USER_NET_SET_MTU = 20, VHOST_USER_SET_SLAVE_REQ_FD = 21, VHOST_USER_IOTLB_MSG = 22, + VHOST_USER_SET_VRING_ENDIAN = 23, VHOST_USER_MAX } VhostUserRequest; @@ -367,8 +369,25 @@ static int vhost_user_set_vring_addr(struct vhost_dev *dev, static int vhost_user_set_vring_endian(struct vhost_dev *dev, struct vhost_vring_state *ring) { - error_report("vhost-user trying to send unhandled ioctl"); - return -1; + bool cross_endian = virtio_has_feature(dev->protocol_features, + VHOST_USER_PROTOCOL_F_CROSS_ENDIAN); + VhostUserMsg msg = { + .request = VHOST_USER_SET_VRING_ENDIAN, + .flags = VHOST_USER_VERSION, + .payload.state = *ring, + .size = sizeof(msg.payload.state), + }; + + if (!cross_endian) { + error_report("vhost-user trying to send unhandled ioctl"); + return -1; + } + + if (vhost_user_write(dev, &msg, NULL, 0) < 0) { + return -1; + } + + return 0; } static int vhost_set_vring(struct vhost_dev *dev, -- cgit v1.2.3