iommu/vt-d: Remove global g_iommus array

The g_iommus and g_num_of_iommus is not used anywhere. Remove them to
avoid dead code.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Steve Wahl <steve.wahl@hpe.com>
Link: https://lore.kernel.org/r/20220702015610.2849494-6-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

Author: LuBaolu

drivers/iommu/intel/iommu.c

@@ -126,9 +126,6 @@ static inline unsigned long virt_to_dma_pfn(void *p)
 	return page_to_dma_pfn(virt_to_page(p));
 }
 
-/* global iommu list, set NULL for ignored DMAR units */
-static struct intel_iommu **g_iommus;
-
 static void __init check_tylersburg_isoch(void);
 static int rwbf_quirk;
 
@@ -287,9 +284,6 @@ static LIST_HEAD(dmar_satc_units);
 #define for_each_rmrr_units(rmrr) \
 	list_for_each_entry(rmrr, &dmar_rmrr_units, list)
 
-/* bitmap for indexing intel_iommus */
-static int g_num_of_iommus;
-
 static void dmar_remove_one_dev_info(struct device *dev);
 
 int dmar_disabled = !IS_ENABLED(CONFIG_INTEL_IOMMU_DEFAULT_ON);
@@ -1694,8 +1688,6 @@ static void free_dmar_iommu(struct intel_iommu *iommu)
 		iommu->domain_ids = NULL;
 	}
 
-	g_iommus[iommu->seq_id] = NULL;
-
 	/* free context mapping */
 	free_context_table(iommu);
 
@@ -2898,36 +2890,6 @@ static int __init init_dmars(void)
 	struct intel_iommu *iommu;
 	int ret;
 
-	/*
-	 * for each drhd
-	 *    allocate root
-	 *    initialize and program root entry to not present
-	 * endfor
-	 */
-	for_each_drhd_unit(drhd) {
-		/*
-		 * lock not needed as this is only incremented in the single
-		 * threaded kernel __init code path all other access are read
-		 * only
-		 */
-		if (g_num_of_iommus < DMAR_UNITS_SUPPORTED) {
-			g_num_of_iommus++;
-			continue;
-		}
-		pr_err_once("Exceeded %d IOMMUs\n", DMAR_UNITS_SUPPORTED);
-	}
-
-	/* Preallocate enough resources for IOMMU hot-addition */
-	if (g_num_of_iommus < DMAR_UNITS_SUPPORTED)
-		g_num_of_iommus = DMAR_UNITS_SUPPORTED;
-
-	g_iommus = kcalloc(g_num_of_iommus, sizeof(struct intel_iommu *),
-			GFP_KERNEL);
-	if (!g_iommus) {
-		ret = -ENOMEM;
-		goto error;
-	}
-
 	ret = intel_cap_audit(CAP_AUDIT_STATIC_DMAR, NULL);
 	if (ret)
 		goto free_iommu;
@@ -2950,8 +2912,6 @@ static int __init init_dmars(void)
 						   intel_pasid_max_id);
 		}
 
-		g_iommus[iommu->seq_id] = iommu;
-
 		intel_iommu_init_qi(iommu);
 
 		ret = iommu_init_domains(iommu);
@@ -3077,9 +3037,6 @@ static int __init init_dmars(void)
 		free_dmar_iommu(iommu);
 	}
 
-	kfree(g_iommus);
-
-error:
 	return ret;
 }
 
@@ -3483,7 +3440,6 @@ static int intel_iommu_add(struct dmar_drhd_unit *dmaru)
 	if (iommu->gcmd & DMA_GCMD_TE)
 		iommu_disable_translation(iommu);
 
-	g_iommus[iommu->seq_id] = iommu;
 	ret = iommu_init_domains(iommu);
 	if (ret == 0)
 		ret = iommu_alloc_root_entry(iommu);