x86/amd-iommu: Keep devices per domain in a list

This patch introduces a list to each protection domain which
keeps all devices associated with the domain. This can be
used later to optimize certain functions and to completly
remove the amd_iommu_pd_table.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

2 files changed, 13 insertions, 0 deletions

diff --git a/arch/x86/include/asm/amd_iommu_types.h b/arch/x86/include/asm/amd_iommu_types.h
index 434e90ed89c5..93953d1922c4 100644
--- a/arch/x86/include/asm/amd_iommu_types.h
+++ b/arch/x86/include/asm/amd_iommu_types.h
@@ -235,6 +235,7 @@ extern bool amd_iommu_np_cache;
  */
 struct protection_domain {
         struct list_head list;  /* for list of all protection domains */
+        struct list_head dev_list; /* List of all devices in this domain */
         spinlock_t lock;        /* mostly used to lock the page table*/
         u16 id;                 /* the domain id written to the device table */
         int mode;               /* paging mode (0-6 levels) */
@@ -251,6 +252,7 @@ struct protection_domain {
  * This struct contains device specific data for the IOMMU
  */
 struct iommu_dev_data {
+        struct list_head list;            /* For domain->dev_list */
         struct device *alias;             /* The Alias Device */
         struct protection_domain *domain; /* Domain the device is bound to */
         atomic_t bind;                    /* Domain attach reverent count */
diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index f5db7d5e444e..530d6080940f 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -1286,6 +1286,7 @@ static struct dma_ops_domain *dma_ops_domain_alloc(void)
         dma_dom->domain.id = domain_id_alloc();
         if (dma_dom->domain.id == 0)
                 goto free_dma_dom;
+        INIT_LIST_HEAD(&dma_dom->domain.dev_list);
         dma_dom->domain.mode = PAGE_MODE_2_LEVEL;
         dma_dom->domain.pt_root = (void *)get_zeroed_page(GFP_KERNEL);
         dma_dom->domain.flags = PD_DMA_OPS_MASK;
@@ -1408,6 +1409,7 @@ static int __attach_device(struct device *dev,
         if (alias != devid) {
                 if (alias_data->domain == NULL) {
                         alias_data->domain = domain;
+                        list_add(&alias_data->list, &domain->dev_list);
                         set_dte_entry(alias, domain);
                 }
 
@@ -1416,6 +1418,7 @@ static int __attach_device(struct device *dev,
 
         if (dev_data->domain == NULL) {
                 dev_data->domain = domain;
+                list_add(&dev_data->list, &domain->dev_list);
                 set_dte_entry(devid, domain);
         }
 
@@ -1460,6 +1463,7 @@ static void __detach_device(struct device *dev)
         struct amd_iommu *iommu = amd_iommu_rlookup_table[devid];
         struct iommu_dev_data *dev_data = get_dev_data(dev);
         struct iommu_dev_data *alias_data;
+        unsigned long flags;
 
         BUG_ON(!iommu);
 
@@ -1469,13 +1473,19 @@ static void __detach_device(struct device *dev)
         if (devid != alias) {
                 alias_data = get_dev_data(dev_data->alias);
                 if (atomic_dec_and_test(&alias_data->bind)) {
+                        spin_lock_irqsave(&alias_data->domain->lock, flags);
                         clear_dte_entry(alias);
+                        list_del(&alias_data->list);
+                        spin_unlock_irqrestore(&alias_data->domain->lock, flags);
                         alias_data->domain = NULL;
                 }
         }
 
         if (atomic_dec_and_test(&dev_data->bind)) {
+                spin_lock_irqsave(&dev_data->domain->lock, flags);
                 clear_dte_entry(devid);
+                list_del(&dev_data->list);
+                spin_unlock_irqrestore(&dev_data->domain->lock, flags);
                 dev_data->domain = NULL;
         }
 
@@ -2294,6 +2304,7 @@ static struct protection_domain *protection_domain_alloc(void)
         domain->id = domain_id_alloc();
         if (!domain->id)
                 goto out_err;
+        INIT_LIST_HEAD(&domain->dev_list);
 
         add_domain_to_list(domain);