iommu: Consolidate IOVA allocator code

In order to share the IOVA allocator with other architectures, break
the unnecssary dependency on the Intel IOMMU driver and move the
remaining IOVA internals to iova.c

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/intel-iommu.c

@@ -485,7 +485,6 @@ __setup("intel_iommu=", intel_iommu_setup);
 
 static struct kmem_cache *iommu_domain_cache;
 static struct kmem_cache *iommu_devinfo_cache;
-static struct kmem_cache *iommu_iova_cache;
 
 static inline void *alloc_pgtable_page(int node)
 {
@@ -523,16 +522,6 @@ static inline void free_devinfo_mem(void *vaddr)
 	kmem_cache_free(iommu_devinfo_cache, vaddr);
 }
 
-struct iova *alloc_iova_mem(void)
-{
-	return kmem_cache_alloc(iommu_iova_cache, GFP_ATOMIC);
-}
-
-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;
@@ -3427,23 +3416,6 @@ static inline int iommu_devinfo_cache_init(void)
 	return ret;
 }
 
-static inline int iommu_iova_cache_init(void)
-{
-	int ret = 0;
-
-	iommu_iova_cache = kmem_cache_create("iommu_iova",
-					 sizeof(struct iova),
-					 0,
-					 SLAB_HWCACHE_ALIGN,
-					 NULL);
-	if (!iommu_iova_cache) {
-		printk(KERN_ERR "Couldn't create iova cache\n");
-		ret = -ENOMEM;
-	}
-
-	return ret;
-}
-
 static int __init iommu_init_mempool(void)
 {
 	int ret;
@@ -3461,7 +3433,7 @@ static int __init iommu_init_mempool(void)
 
 	kmem_cache_destroy(iommu_domain_cache);
 domain_error:
-	kmem_cache_destroy(iommu_iova_cache);
+	iommu_iova_cache_destroy();
 
 	return -ENOMEM;
 }
@@ -3470,8 +3442,7 @@ static void __init iommu_exit_mempool(void)
 {
 	kmem_cache_destroy(iommu_devinfo_cache);
 	kmem_cache_destroy(iommu_domain_cache);
-	kmem_cache_destroy(iommu_iova_cache);
-
+	iommu_iova_cache_destroy();
 }
 
 static void quirk_ioat_snb_local_iommu(struct pci_dev *pdev)

drivers/iommu/iova.c

@@ -18,6 +18,41 @@
  */
 
 #include <linux/iova.h>
+#include <linux/slab.h>
+
+static struct kmem_cache *iommu_iova_cache;
+
+int iommu_iova_cache_init(void)
+{
+	int ret = 0;
+
+	iommu_iova_cache = kmem_cache_create("iommu_iova",
+					 sizeof(struct iova),
+					 0,
+					 SLAB_HWCACHE_ALIGN,
+					 NULL);
+	if (!iommu_iova_cache) {
+		pr_err("Couldn't create iova cache\n");
+		ret = -ENOMEM;
+	}
+
+	return ret;
+}
+
+void iommu_iova_cache_destroy(void)
+{
+	kmem_cache_destroy(iommu_iova_cache);
+}
+
+struct iova *alloc_iova_mem(void)
+{
+	return kmem_cache_alloc(iommu_iova_cache, GFP_ATOMIC);
+}
+
+void free_iova_mem(struct iova *iova)
+{
+	kmem_cache_free(iommu_iova_cache, iova);
+}
 
 void
 init_iova_domain(struct iova_domain *iovad, unsigned long pfn_32bit)

include/linux/iova.h

@@ -39,6 +39,9 @@ static inline unsigned long iova_size(struct iova *iova)
 	return iova->pfn_hi - iova->pfn_lo + 1;
 }
 
+int iommu_iova_cache_init(void);
+void iommu_iova_cache_destroy(void);
+
 struct iova *alloc_iova_mem(void);
 void free_iova_mem(struct iova *iova);
 void free_iova(struct iova_domain *iovad, unsigned long pfn);