iommu: iova: Move iova cache management to the iova library

This is necessary to separate intel-iommu from the iova library.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 2d7349a3ee1496408f051b4da8accebc8dd02ec1..7b27bcdc30ad3bc313b527670488729c0872c054 100644 (file)
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -3711,7 +3711,7 @@ static inline int iommu_devinfo_cache_init(void)
 static int __init iommu_init_mempool(void)
 {
        int ret;
-       ret = iommu_iova_cache_init();
+       ret = iova_cache_get();
        if (ret)
                return ret;
 
@@ -3725,7 +3725,7 @@ static int __init iommu_init_mempool(void)
 
        kmem_cache_destroy(iommu_domain_cache);
 domain_error:
-       iommu_iova_cache_destroy();
+       iova_cache_put();
 
        return -ENOMEM;
 }
@@ -3734,7 +3734,7 @@ static void __init iommu_exit_mempool(void)
 {
        kmem_cache_destroy(iommu_devinfo_cache);
        kmem_cache_destroy(iommu_domain_cache);
-       iommu_iova_cache_destroy();
+       iova_cache_put();
 }
 
 static void quirk_ioat_snb_local_iommu(struct pci_dev *pdev)

diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
index b7c3d923f3e1c0569c42492d435b7c4d9a321caa..400f4d1b566f5ea43c36ac4ccb054e137aeb4d45 100644 (file)
--- a/drivers/iommu/iova.c
+++ b/drivers/iommu/iova.c
@@ -20,40 +20,6 @@
 #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 granule,
        unsigned long start_pfn, unsigned long pfn_32bit)
@@ -242,6 +208,55 @@ iova_insert_rbtree(struct rb_root *root, struct iova *iova)
        rb_insert_color(&iova->node, root);
 }
 
+static struct kmem_cache *iova_cache;
+static unsigned int iova_cache_users;
+static DEFINE_MUTEX(iova_cache_mutex);
+
+struct iova *alloc_iova_mem(void)
+{
+       return kmem_cache_alloc(iova_cache, GFP_ATOMIC);
+}
+EXPORT_SYMBOL(alloc_iova_mem);
+
+void free_iova_mem(struct iova *iova)
+{
+       kmem_cache_free(iova_cache, iova);
+}
+EXPORT_SYMBOL(free_iova_mem);
+
+int iova_cache_get(void)
+{
+       mutex_lock(&iova_cache_mutex);
+       if (!iova_cache_users) {
+               iova_cache = kmem_cache_create(
+                       "iommu_iova", sizeof(struct iova), 0,
+                       SLAB_HWCACHE_ALIGN, NULL);
+               if (!iova_cache) {
+                       mutex_unlock(&iova_cache_mutex);
+                       printk(KERN_ERR "Couldn't create iova cache\n");
+                       return -ENOMEM;
+               }
+       }
+
+       iova_cache_users++;
+       mutex_unlock(&iova_cache_mutex);
+
+       return 0;
+}
+
+void iova_cache_put(void)
+{
+       mutex_lock(&iova_cache_mutex);
+       if (WARN_ON(!iova_cache_users)) {
+               mutex_unlock(&iova_cache_mutex);
+               return;
+       }
+       iova_cache_users--;
+       if (!iova_cache_users)
+               kmem_cache_destroy(iova_cache);
+       mutex_unlock(&iova_cache_mutex);
+}
+
 /**
  * alloc_iova - allocates an iova
  * @iovad: - iova domain in question

diff --git a/include/linux/iova.h b/include/linux/iova.h
index 3920a19d819415bc3109a491171e32388f9bda18..92f7177db2ce869a29db8813911c3a8a0c2b86b2 100644 (file)
--- a/include/linux/iova.h
+++ b/include/linux/iova.h
@@ -68,8 +68,8 @@ static inline unsigned long iova_pfn(struct iova_domain *iovad, dma_addr_t iova)
        return iova >> iova_shift(iovad);
 }
 
-int iommu_iova_cache_init(void);
-void iommu_iova_cache_destroy(void);
+int iova_cache_get(void);
+void iova_cache_put(void);
 
 struct iova *alloc_iova_mem(void);
 void free_iova_mem(struct iova *iova);