iommu/vt-d: Move PRI enablement in probe path

Update PRI enablement to use the new method, similar to the amd iommu
driver. Enable PRI in the device probe path and disable it when the device
is released. PRI is enabled throughout the device's iommu lifecycle. The
infrastructure for the iommu subsystem to handle iopf requests is created
during iopf enablement and released during iopf disablement.  All invalid
page requests from the device are automatically handled by the iommu
subsystem if iopf is not enabled. Add iopf_refcount to track the iopf
enablement.

Convert the return type of intel_iommu_disable_iopf() to void, as there
is no way to handle a failure when disabling this feature.  Make
intel_iommu_enable/disable_iopf() helpers global, as they will be used
beyond the current file in the subsequent patch.

The iopf_refcount is not protected by any lock. This is acceptable, as
there is no concurrent access to it in the current code. The following
patch will address this by moving it to the domain attach/detach paths,
which are protected by the iommu group mutex.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Tested-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Link: https://lore.kernel.org/r/20250228092631.3425464-6-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

0 files changed, 0 insertions, 0 deletions