x86/amd-iommu: Implement protection domain list

This patch adds code to keep a global list of all protection
domains. This allows to simplify the resume code.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

arch/x86/include/asm/amd_iommu_types.h

@@ -231,6 +231,7 @@ extern bool amd_iommu_dump;
  * independent of their use.
  */
 struct protection_domain {
+	struct list_head list;  /* for list of all protection domains */
 	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) */
@@ -375,6 +376,12 @@ extern struct amd_iommu *amd_iommus[MAX_IOMMUS];
 /* Number of IOMMUs present in the system */
 extern int amd_iommus_present;
 
+/*
+ * Declarations for the global list of all protection domains
+ */
+extern spinlock_t amd_iommu_pd_lock;
+extern struct list_head amd_iommu_pd_list;
+
 /*
  * Structure defining one entry in the device table
  */

arch/x86/kernel/amd_iommu.c

@@ -985,6 +985,31 @@ static void dma_ops_free_addresses(struct dma_ops_domain *dom,
  *
  ****************************************************************************/
 
+/*
+ * This function adds a protection domain to the global protection domain list
+ */
+static void add_domain_to_list(struct protection_domain *domain)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&amd_iommu_pd_lock, flags);
+	list_add(&domain->list, &amd_iommu_pd_list);
+	spin_unlock_irqrestore(&amd_iommu_pd_lock, flags);
+}
+
+/*
+ * This function removes a protection domain to the global
+ * protection domain list
+ */
+static void del_domain_from_list(struct protection_domain *domain)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&amd_iommu_pd_lock, flags);
+	list_del(&domain->list);
+	spin_unlock_irqrestore(&amd_iommu_pd_lock, flags);
+}
+
 static u16 domain_id_alloc(void)
 {
 	unsigned long flags;
@@ -1073,6 +1098,8 @@ static void dma_ops_domain_free(struct dma_ops_domain *dom)
 	if (!dom)
 		return;
 
+	del_domain_from_list(&dom->domain);
+
 	free_pagetable(&dom->domain);
 
 	for (i = 0; i < APERTURE_MAX_RANGES; ++i) {
@@ -1113,6 +1140,8 @@ static struct dma_ops_domain *dma_ops_domain_alloc(struct amd_iommu *iommu)
 	dma_dom->need_flush = false;
 	dma_dom->target_dev = 0xffff;
 
+	add_domain_to_list(&dma_dom->domain);
+
 	if (alloc_new_range(iommu, dma_dom, true, GFP_KERNEL))
 		goto free_dma_dom;
 
@@ -2188,6 +2217,8 @@ static void protection_domain_free(struct protection_domain *domain)
 	if (!domain)
 		return;
 
+	del_domain_from_list(domain);
+
 	if (domain->id)
 		domain_id_free(domain->id);
 
@@ -2207,6 +2238,8 @@ static struct protection_domain *protection_domain_alloc(void)
 	if (!domain->id)
 		goto out_err;
 
+	add_domain_to_list(domain);
+
 	return domain;
 
 out_err:

arch/x86/kernel/amd_iommu_init.c

@@ -141,6 +141,12 @@ LIST_HEAD(amd_iommu_list);		/* list of all AMD IOMMUs in the
 struct amd_iommu *amd_iommus[MAX_IOMMUS];
 int amd_iommus_present;
 
+/*
+ * List of protection domains - used during resume
+ */
+LIST_HEAD(amd_iommu_pd_list);
+spinlock_t amd_iommu_pd_lock;
+
 /*
  * Pointer to the device table which is shared by all AMD IOMMUs
  * it is indexed by the PCI device id or the HT unit id and contains
@@ -1263,6 +1269,8 @@ static int __init amd_iommu_init(void)
 	 */
 	amd_iommu_pd_alloc_bitmap[0] = 1;
 
+	spin_lock_init(&amd_iommu_pd_lock);
+
 	/*
 	 * now the data structures are allocated and basically initialized
 	 * start the real acpi table scan