This moves the noiommu device determination and noiommu taint out of vfio_group_find_or_alloc(). noiommu device is determined in __vfio_register_dev() and result is stored in flag vfio_device->noiommu, the noiommu taint is added in the end of __vfio_register_dev().
This is also a preparation for compiling out vfio_group infrastructure as it makes the noiommu detection and taint common between the cdev path and group path though cdev path does not support noiommu. Suggested-by: Alex Williamson <[email protected]> Signed-off-by: Yi Liu <[email protected]> --- drivers/vfio/group.c | 15 --------------- drivers/vfio/vfio_main.c | 31 ++++++++++++++++++++++++++++++- include/linux/vfio.h | 1 + 3 files changed, 31 insertions(+), 16 deletions(-) diff --git a/drivers/vfio/group.c b/drivers/vfio/group.c index 653b62f93474..64cdd0ea8825 100644 --- a/drivers/vfio/group.c +++ b/drivers/vfio/group.c @@ -668,21 +668,6 @@ static struct vfio_group *vfio_group_find_or_alloc(struct device *dev) struct vfio_group *group; iommu_group = iommu_group_get(dev); - if (!iommu_group && vfio_noiommu) { - /* - * With noiommu enabled, create an IOMMU group for devices that - * don't already have one, implying no IOMMU hardware/driver - * exists. Taint the kernel because we're about to give a DMA - * capable device to a user without IOMMU protection. - */ - group = vfio_noiommu_group_alloc(dev, VFIO_NO_IOMMU); - if (!IS_ERR(group)) { - add_taint(TAINT_USER, LOCKDEP_STILL_OK); - dev_warn(dev, "Adding kernel taint for vfio-noiommu group on device\n"); - } - return group; - } - if (!iommu_group) return ERR_PTR(-EINVAL); diff --git a/drivers/vfio/vfio_main.c b/drivers/vfio/vfio_main.c index 6d8f9b0f3637..00a699b9f76b 100644 --- a/drivers/vfio/vfio_main.c +++ b/drivers/vfio/vfio_main.c @@ -265,6 +265,18 @@ static int vfio_init_device(struct vfio_device *device, struct device *dev, return ret; } +static int vfio_device_set_noiommu(struct vfio_device *device) +{ + struct iommu_group *iommu_group = iommu_group_get(device->dev); + + if (!iommu_group && !vfio_noiommu) + return -EINVAL; + + device->noiommu = !iommu_group; + iommu_group_put(iommu_group); /* Accepts NULL */ + return 0; +} + static int __vfio_register_dev(struct vfio_device *device, enum vfio_group_type type) { @@ -277,6 +289,13 @@ static int __vfio_register_dev(struct vfio_device *device, !device->ops->detach_ioas))) return -EINVAL; + /* Only physical devices can be noiommu device */ + if (type == VFIO_IOMMU) { + ret = vfio_device_set_noiommu(device); + if (ret) + return ret; + } + /* * If the driver doesn't specify a set then the device is added to a * singleton set just for itself. @@ -288,7 +307,8 @@ static int __vfio_register_dev(struct vfio_device *device, if (ret) return ret; - ret = vfio_device_set_group(device, type); + ret = vfio_device_set_group(device, + device->noiommu ? VFIO_NO_IOMMU : type); if (ret) return ret; @@ -301,6 +321,15 @@ static int __vfio_register_dev(struct vfio_device *device, vfio_device_group_register(device); + if (device->noiommu) { + /* + * noiommu deivces have no IOMMU hardware/driver. Taint the + * kernel because we're about to give a DMA capable device to + * a user without IOMMU protection. + */ + add_taint(TAINT_USER, LOCKDEP_STILL_OK); + dev_warn(device->dev, "Adding kernel taint for vfio-noiommu on device\n"); + } return 0; err_out: vfio_device_remove_group(device); diff --git a/include/linux/vfio.h b/include/linux/vfio.h index e80a8ac86e46..183e620009e7 100644 --- a/include/linux/vfio.h +++ b/include/linux/vfio.h @@ -67,6 +67,7 @@ struct vfio_device { bool iommufd_attached; #endif bool cdev_opened:1; + bool noiommu:1; }; /** -- 2.34.1
