From bc91df5c70ac720eca18bd1f4a288f2582713d3e Mon Sep 17 00:00:00 2001 From: Si-Wei Liu Date: Sat, 21 Oct 2023 02:25:17 -0700 Subject: vhost-vdpa: clean iotlb map during reset for older userspace Using .compat_reset op from the previous patch, the buggy .reset behaviour can be kept as-is on older userspace apps, which don't ack the IOTLB_PERSIST backend feature. As this compatibility quirk is limited to those drivers that used to be buggy in the past, it won't affect change the behaviour or affect ABI on the setups with API compliant driver. The separation of .compat_reset from the regular .reset allows vhost-vdpa able to know which driver had broken behaviour before, so it can apply the corresponding compatibility quirk to the individual driver whenever needed. Compared to overloading the existing .reset with flags, .compat_reset won't cause any extra burden to the implementation of every compliant driver. [mst: squashed in two fixup commits] Message-Id: <1697880319-4937-6-git-send-email-si-wei.liu@oracle.com> Message-Id: <1698102863-21122-1-git-send-email-si-wei.liu@oracle.com> Reported-by: Dragos Tatulea Tested-by: Dragos Tatulea Message-Id: <1698275594-19204-1-git-send-email-si-wei.liu@oracle.com> Reported-by: Lei Yang Signed-off-by: Si-Wei Liu Signed-off-by: Michael S. Tsirkin Tested-by: Lei Yang --- include/linux/vdpa.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h index 6b8cbf75712d..db15ac07f8a6 100644 --- a/include/linux/vdpa.h +++ b/include/linux/vdpa.h @@ -519,14 +519,17 @@ static inline struct device *vdpa_get_dma_dev(struct vdpa_device *vdev) return vdev->dma_dev; } -static inline int vdpa_reset(struct vdpa_device *vdev) +static inline int vdpa_reset(struct vdpa_device *vdev, u32 flags) { const struct vdpa_config_ops *ops = vdev->config; int ret; down_write(&vdev->cf_lock); vdev->features_valid = false; - ret = ops->reset(vdev); + if (ops->compat_reset && flags) + ret = ops->compat_reset(vdev, flags); + else + ret = ops->reset(vdev); up_write(&vdev->cf_lock); return ret; } -- cgit v1.2.3