iommu/vt-d: Remove duplicate identity domain flag

The iommu_domain data structure already has the "type" field to keep the
type of a domain. It's unnecessary to have the DOMAIN_FLAG_STATIC_IDENTITY
flag in the vt-d implementation. This cleans it up with no functionality
change.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210926114535.923263-1-baolu.lu@linux.intel.com
Link: https://lore.kernel.org/r/20211014053839.727419-4-baolu.lu@linux.intel.comSigned-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/intel/iommu.c

@@ -528,7 +528,7 @@ static inline void free_devinfo_mem(void *vaddr)
 
 static inline int domain_type_is_si(struct dmar_domain *domain)
 {
-	return domain->flags & DOMAIN_FLAG_STATIC_IDENTITY;
+	return domain->domain.type == IOMMU_DOMAIN_IDENTITY;
 }
 
 static inline bool domain_use_first_level(struct dmar_domain *domain)
@@ -1996,7 +1996,7 @@ static bool first_level_by_default(void)
 	return scalable_mode_support() && intel_cap_flts_sanity();
 }
 
-static struct dmar_domain *alloc_domain(int flags)
+static struct dmar_domain *alloc_domain(unsigned int type)
 {
 	struct dmar_domain *domain;
 
@@ -2006,7 +2006,6 @@ static struct dmar_domain *alloc_domain(int flags)
 
 	memset(domain, 0, sizeof(*domain));
 	domain->nid = NUMA_NO_NODE;
-	domain->flags = flags;
 	if (first_level_by_default())
 		domain->flags |= DOMAIN_FLAG_USE_FIRST_LEVEL;
 	domain->has_iotlb_device = false;
@@ -2825,7 +2824,7 @@ static int __init si_domain_init(int hw)
 	struct device *dev;
 	int i, nid, ret;
 
-	si_domain = alloc_domain(DOMAIN_FLAG_STATIC_IDENTITY);
+	si_domain = alloc_domain(IOMMU_DOMAIN_IDENTITY);
 	if (!si_domain)
 		return -EFAULT;
 
@@ -4634,7 +4633,7 @@ static struct iommu_domain *intel_iommu_domain_alloc(unsigned type)
 	case IOMMU_DOMAIN_DMA:
 	case IOMMU_DOMAIN_DMA_FQ:
 	case IOMMU_DOMAIN_UNMANAGED:
-		dmar_domain = alloc_domain(0);
+		dmar_domain = alloc_domain(type);
 		if (!dmar_domain) {
 			pr_err("Can't allocate dmar_domain\n");
 			return NULL;

include/linux/intel-iommu.h

@@ -517,9 +517,6 @@ struct context_entry {
 	u64 hi;
 };
 
-/* si_domain contains mulitple devices */
-#define DOMAIN_FLAG_STATIC_IDENTITY		BIT(0)
-
 /*
  * When VT-d works in the scalable mode, it allows DMA translation to
  * happen through either first level or second level page table. This