mirror of
https://github.com/torvalds/linux
synced 2024-10-01 17:00:41 +00:00
iommu/vt-d: Remove caching mode check before device TLB flush
The Caching Mode (CM) of the Intel IOMMU indicates if the hardware implementation caches not-present or erroneous translation-structure entries except for the first-stage translation. The caching mode is irrelevant to the device TLB, therefore there is no need to check it before a device TLB invalidation operation. Remove two caching mode checks before device TLB invalidation in the driver. The removal of these checks doesn't change the driver's behavior in critical map/unmap paths. Hence, there is no functionality or performance impact, especially since commit <29b32839725f> ("iommu/vt-d: Do not use flush-queue when caching-mode is on") has already disabled flush-queue for caching mode. Therefore, caching mode will never call intel_flush_iotlb_all(). Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Yi Liu <yi.l.liu@intel.com> Link: https://lore.kernel.org/r/20240415013835.9527-1-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
parent
621b7e54f2
commit
304b3bde24
|
@ -1502,11 +1502,7 @@ static void iommu_flush_iotlb_psi(struct intel_iommu *iommu,
|
|||
else
|
||||
__iommu_flush_iotlb_psi(iommu, did, pfn, pages, ih);
|
||||
|
||||
/*
|
||||
* In caching mode, changes of pages from non-present to present require
|
||||
* flush. However, device IOTLB doesn't need to be flushed in this case.
|
||||
*/
|
||||
if (!cap_caching_mode(iommu->cap) || !map)
|
||||
if (!map)
|
||||
iommu_flush_dev_iotlb(domain, addr, mask);
|
||||
}
|
||||
|
||||
|
@ -1580,8 +1576,7 @@ static void intel_flush_iotlb_all(struct iommu_domain *domain)
|
|||
iommu->flush.flush_iotlb(iommu, did, 0, 0,
|
||||
DMA_TLB_DSI_FLUSH);
|
||||
|
||||
if (!cap_caching_mode(iommu->cap))
|
||||
iommu_flush_dev_iotlb(dmar_domain, 0, MAX_AGAW_PFN_WIDTH);
|
||||
iommu_flush_dev_iotlb(dmar_domain, 0, MAX_AGAW_PFN_WIDTH);
|
||||
}
|
||||
|
||||
if (dmar_domain->nested_parent)
|
||||
|
|
Loading…
Reference in a new issue