Commit 5bdd86ec authored by Lu Baolu's avatar Lu Baolu Committed by Joerg Roedel
Browse files

iommu/vt-d: Remove domain_update_iommu_superpage() 



The requirement for consistent super page support across all the IOMMU
hardware in the system has been removed. In the past, if a new IOMMU
was hot-added and lacked consistent super page capability, the hot-add
process would be aborted. However, with the updated attachment semantics,
it is now permissible for the super page capability to vary among
different IOMMU hardware units.

Signed-off-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20241021085125.192333-6-baolu.lu@linux.intel.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent c376a345

drivers/iommu/intel/iommu.c

+1 −38
Original line number Diff line number Diff line
@@ -352,36 +352,6 @@ static bool iommu_paging_structure_coherency(struct intel_iommu *iommu) 
			ecap_smpwc(iommu->ecap) : ecap_coherent(iommu->ecap);

}



static int domain_update_iommu_superpage(struct dmar_domain *domain,

					 struct intel_iommu *skip)

{

	struct dmar_drhd_unit *drhd;

	struct intel_iommu *iommu;

	int mask = 0x3;



	if (!intel_iommu_superpage)

		return 0;



	/* set iommu_superpage to the smallest common denominator */

	rcu_read_lock();

	for_each_active_iommu(iommu, drhd) {

		if (iommu != skip) {

			if (domain && domain->use_first_level) {

				if (!cap_fl1gp_support(iommu->cap))

					mask = 0x1;

			} else {

				mask &= cap_super_page_val(iommu->cap);

			}



			if (!mask)

				break;

		}

	}

	rcu_read_unlock();



	return fls(mask);

}



/* Return the super pagesize bitmap if supported. */

static unsigned long domain_super_pgsize_bitmap(struct dmar_domain *domain)

{
@@ -2605,20 +2575,13 @@ int dmar_parse_one_satc(struct acpi_dmar_header *hdr, void *arg) 


static int intel_iommu_add(struct dmar_drhd_unit *dmaru)

{

	int sp, ret;

	struct intel_iommu *iommu = dmaru->iommu;

	int ret;



	ret = intel_cap_audit(CAP_AUDIT_HOTPLUG_DMAR, iommu);

	if (ret)

		goto out;



	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",

			iommu->name);

		return -ENXIO;

	}



	/*

	 * Disable translation if already enabled prior to OS handover.

	 */