iommu/vt-d: Introduce helper functions to improve code readability

Introduce domain_type_is_vm() and domain_type_is_vm_or_si() to improve
code readability.

Also kill useless macro DOMAIN_FLAG_P2P_MULTIPLE_DEVICES.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

1 files changed, 26 insertions, 33 deletions

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index d77009bdade5..52250b3e58d1 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -320,16 +320,13 @@ static inline int first_pte_in_page(struct dma_pte *pte)
 static struct dmar_domain *si_domain;
 static int hw_pass_through = 1;
 
-/* devices under the same p2p bridge are owned in one domain */
-#define DOMAIN_FLAG_P2P_MULTIPLE_DEVICES (1 << 0)
-
 /* domain represents a virtual machine, more than one devices
  * across iommus may be owned in one domain, e.g. kvm guest.
  */
-#define DOMAIN_FLAG_VIRTUAL_MACHINE     (1 << 1)
+#define DOMAIN_FLAG_VIRTUAL_MACHINE     (1 << 0)
 
 /* si_domain contains mulitple devices */
-#define DOMAIN_FLAG_STATIC_IDENTITY     (1 << 2)
+#define DOMAIN_FLAG_STATIC_IDENTITY     (1 << 1)
 
 /* define the limit of IOMMUs supported in each domain */
 #ifdef  CONFIG_X86
@@ -539,6 +536,16 @@ void free_iova_mem(struct iova *iova)
         kmem_cache_free(iommu_iova_cache, iova);
 }
 
+static inline int domain_type_is_vm(struct dmar_domain *domain)
+{
+        return domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE;
+}
+
+static inline int domain_type_is_vm_or_si(struct dmar_domain *domain)
+{
+        return domain->flags & (DOMAIN_FLAG_VIRTUAL_MACHINE |
+                                DOMAIN_FLAG_STATIC_IDENTITY);
+}
 
 static int __iommu_calculate_agaw(struct intel_iommu *iommu, int max_gaw)
 {
@@ -579,9 +586,7 @@ static struct intel_iommu *domain_get_iommu(struct dmar_domain *domain)
         int iommu_id;
 
         /* si_domain and vm domain should not get here. */
-        BUG_ON(domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE);
-        BUG_ON(domain->flags & DOMAIN_FLAG_STATIC_IDENTITY);
-
+        BUG_ON(domain_type_is_vm_or_si(domain));
         iommu_id = find_first_bit(domain->iommu_bmp, g_num_of_iommus);
         if (iommu_id < 0 || iommu_id >= g_num_of_iommus)
                 return NULL;
@@ -1497,7 +1502,7 @@ static void free_dmar_iommu(struct intel_iommu *iommu)
         free_context_table(iommu);
 }
 
-static struct dmar_domain *alloc_domain(bool vm)
+static struct dmar_domain *alloc_domain(int flags)
 {
         /* domain id for virtual machine, it won't be set in context */
         static atomic_t vm_domid = ATOMIC_INIT(0);
@@ -1507,16 +1512,13 @@ static struct dmar_domain *alloc_domain(bool vm)
         if (!domain)
                 return NULL;
 
+        memset(domain, 0, sizeof(*domain));
         domain->nid = -1;
-        domain->iommu_count = 0;
-        memset(domain->iommu_bmp, 0, sizeof(domain->iommu_bmp));
-        domain->flags = 0;
+        domain->flags = flags;
         spin_lock_init(&domain->iommu_lock);
         INIT_LIST_HEAD(&domain->devices);
-        if (vm) {
+        if (flags & DOMAIN_FLAG_VIRTUAL_MACHINE)
                 domain->id = atomic_inc_return(&vm_domid);
-                domain->flags = DOMAIN_FLAG_VIRTUAL_MACHINE;
-        }
 
         return domain;
 }
@@ -1704,7 +1706,7 @@ static void domain_exit(struct dmar_domain *domain)
         /* clear attached or cached domains */
         rcu_read_lock();
         for_each_active_iommu(iommu, drhd)
-                if (domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE ||
+                if (domain_type_is_vm(domain) ||
                     test_bit(iommu->seq_id, domain->iommu_bmp))
                         iommu_detach_domain(domain, iommu);
         rcu_read_unlock();
@@ -1746,8 +1748,7 @@ static int domain_context_mapping_one(struct dmar_domain *domain,
         id = domain->id;
         pgd = domain->pgd;
 
-        if (domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE ||
-            domain->flags & DOMAIN_FLAG_STATIC_IDENTITY) {
+        if (domain_type_is_vm_or_si(domain)) {
                 int found = 0;
 
                 /* find an available domain id for this device in iommu */
@@ -2094,7 +2095,7 @@ static void domain_remove_dev_info(struct dmar_domain *domain)
                 iommu_disable_dev_iotlb(info);
                 iommu_detach_dev(info->iommu, info->bus, info->devfn);
 
-                if (domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE) {
+                if (domain_type_is_vm(domain)) {
                         iommu_detach_dependent_devices(info->iommu, info->dev);
                         /* clear this iommu in iommu_bmp, update iommu count
                          * and capabilities
@@ -2160,8 +2161,6 @@ static struct dmar_domain *dmar_insert_dev_info(struct intel_iommu *iommu,
         info->dev = dev;
         info->domain = domain;
         info->iommu = iommu;
-        if (!dev)
-                domain->flags |= DOMAIN_FLAG_P2P_MULTIPLE_DEVICES;
 
         spin_lock_irqsave(&device_domain_lock, flags);
         if (dev)
@@ -2233,7 +2232,7 @@ static struct dmar_domain *get_domain_for_dev(struct device *dev, int gaw)
         }
 
         /* Allocate and initialize new domain for the device */
-        domain = alloc_domain(false);
+        domain = alloc_domain(0);
         if (!domain)
                 return NULL;
 
@@ -2408,12 +2407,10 @@ static int __init si_domain_init(int hw)
         struct intel_iommu *iommu;
         int nid, ret = 0;
 
-        si_domain = alloc_domain(false);
+        si_domain = alloc_domain(DOMAIN_FLAG_STATIC_IDENTITY);
         if (!si_domain)
                 return -EFAULT;
 
-        si_domain->flags = DOMAIN_FLAG_STATIC_IDENTITY;
-
         for_each_active_iommu(iommu, drhd) {
                 ret = iommu_attach_domain(si_domain, iommu);
                 if (ret) {
@@ -3860,9 +3857,7 @@ static int device_notifier(struct notifier_block *nb,
 
         down_read(&dmar_global_lock);
         domain_remove_one_dev_info(domain, dev);
-        if (!(domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE) &&
-            !(domain->flags & DOMAIN_FLAG_STATIC_IDENTITY) &&
-            list_empty(&domain->devices))
+        if (!domain_type_is_vm_or_si(domain) && list_empty(&domain->devices))
                 domain_exit(domain);
         up_read(&dmar_global_lock);
 
@@ -4167,8 +4162,7 @@ static void domain_remove_one_dev_info(struct dmar_domain *domain,
                 domain_update_iommu_cap(domain);
                 spin_unlock_irqrestore(&domain->iommu_lock, tmp_flags);
 
-                if (!(domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE) &&
-                    !(domain->flags & DOMAIN_FLAG_STATIC_IDENTITY)) {
+                if (!domain_type_is_vm_or_si(domain)) {
                         spin_lock_irqsave(&iommu->lock, tmp_flags);
                         clear_bit(domain->id, iommu->domain_ids);
                         iommu->domains[domain->id] = NULL;
@@ -4206,7 +4200,7 @@ static int intel_iommu_domain_init(struct iommu_domain *domain)
 {
         struct dmar_domain *dmar_domain;
 
-        dmar_domain = alloc_domain(true);
+        dmar_domain = alloc_domain(DOMAIN_FLAG_VIRTUAL_MACHINE);
         if (!dmar_domain) {
                 printk(KERN_ERR
                         "intel_iommu_domain_init: dmar_domain == NULL\n");
@@ -4250,8 +4244,7 @@ static int intel_iommu_attach_device(struct iommu_domain *domain,
 
                 old_domain = find_domain(dev);
                 if (old_domain) {
-                        if (dmar_domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE ||
-                            dmar_domain->flags & DOMAIN_FLAG_STATIC_IDENTITY)
+                        if (domain_type_is_vm_or_si(dmar_domain))
                                 domain_remove_one_dev_info(old_domain, dev);
                         else
                                 domain_remove_dev_info(old_domain);