From c471ad0e9bd46ca5f5c9c796e727230e043a091d Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Wed, 11 Jan 2017 12:32:12 +0800 Subject: vhost_net: device IOTLB support This patches implements Device IOTLB support for vhost kernel. This is done through: 1) switch to use dma helpers when map/unmap vrings from vhost codes 2) introduce a set of VhostOps to: - setting up device IOTLB request callback - processing device IOTLB request - processing device IOTLB invalidation 2) kernel support for Device IOTLB API: - allow vhost-net to query the IOMMU IOTLB entry through eventfd - enable the ability for qemu to update a specified mapping of vhost - through ioctl. - enable the ability to invalidate a specified range of iova for the device IOTLB of vhost through ioctl. In x86/intel_iommu case this is triggered through iommu memory region notifier from device IOTLB invalidation descriptor processing routine. With all the above, kernel vhost_net can co-operate with userspace IOMMU. For vhost-user, the support could be easily done on top by implementing the VhostOps. Cc: Michael S. Tsirkin Signed-off-by: Jason Wang Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- net/tap.c | 1 + 1 file changed, 1 insertion(+) (limited to 'net') diff --git a/net/tap.c b/net/tap.c index b6896a7b7c..86071b2659 100644 --- a/net/tap.c +++ b/net/tap.c @@ -696,6 +696,7 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, "tap: open vhost char device failed"); return; } + fcntl(vhostfd, F_SETFL, O_NONBLOCK); } options.opaque = (void *)(uintptr_t)vhostfd; -- cgit v1.2.1