Commit e8055226 authored by Lu Baolu's avatar Lu Baolu Committed by Joerg Roedel
Browse files

iommu/vt-d: Remove domain_update_iommu_snooping() 



The IOMMU force snooping capability is not required to be consistent
among all the IOMMUs anymore. Remove force snooping capability check
in the IOMMU hot-add path and domain_update_iommu_snooping() becomes
a dead code now.

Signed-off-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20220508123525.1973626-1-baolu.lu@linux.intel.com
Link: https://lore.kernel.org/r/20220510023407.2759143-8-baolu.lu@linux.intel.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent fc0051cb

drivers/iommu/intel/iommu.c

+1 −33
Original line number Diff line number Diff line
@@ -533,33 +533,6 @@ static void domain_update_iommu_coherency(struct dmar_domain *domain) 
	rcu_read_unlock();

}



static bool domain_update_iommu_snooping(struct intel_iommu *skip)

{

	struct dmar_drhd_unit *drhd;

	struct intel_iommu *iommu;

	bool ret = true;



	rcu_read_lock();

	for_each_active_iommu(iommu, drhd) {

		if (iommu != skip) {

			/*

			 * If the hardware is operating in the scalable mode,

			 * the snooping control is always supported since we

			 * always set PASID-table-entry.PGSNP bit if the domain

			 * is managed outside (UNMANAGED).

			 */

			if (!sm_supported(iommu) &&

			    !ecap_sc_support(iommu->ecap)) {

				ret = false;

				break;

			}

		}

	}

	rcu_read_unlock();



	return ret;

}



static int domain_update_iommu_superpage(struct dmar_domain *domain,

					 struct intel_iommu *skip)

{
@@ -3572,12 +3545,7 @@ static int intel_iommu_add(struct dmar_drhd_unit *dmaru) 
			iommu->name);

		return -ENXIO;

	}

	if (!ecap_sc_support(iommu->ecap) &&

	    domain_update_iommu_snooping(iommu)) {

		pr_warn("%s: Doesn't support snooping.\n",

			iommu->name);

		return -ENXIO;

	}



	sp = domain_update_iommu_superpage(NULL, iommu) - 1;

	if (sp >= 0 && !(cap_super_page_val(iommu->cap) & (1 << sp))) {

		pr_warn("%s: Doesn't support large page.\n",