Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

[karo-tx-linux.git] / drivers / iommu / iova.c

diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
index b7c3d923f3e1c0569c42492d435b7c4d9a321caa..fa0adef32bd6d3a4af1b97ee3b1fb22dde6c225f 100644 (file)
--- a/drivers/iommu/iova.c
+++ b/drivers/iommu/iova.c
@@ -18,42 +18,9 @@
  */
 
 #include <linux/iova.h>
+#include <linux/module.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)
@@ -72,6 +39,7 @@ init_iova_domain(struct iova_domain *iovad, unsigned long granule,
        iovad->start_pfn = start_pfn;
        iovad->dma_32bit_pfn = pfn_32bit;
 }
+EXPORT_SYMBOL_GPL(init_iova_domain);
 
 static struct rb_node *
 __get_cached_rbnode(struct iova_domain *iovad, unsigned long *limit_pfn)
@@ -120,19 +88,14 @@ __cached_rbnode_delete_update(struct iova_domain *iovad, struct iova *free)
        }
 }
 
-/* Computes the padding size required, to make the
- * the start address naturally aligned on its size
+/*
+ * Computes the padding size required, to make the start address
+ * naturally aligned on the power-of-two order of its size
  */
-static int
-iova_get_pad_size(int size, unsigned int limit_pfn)
+static unsigned int
+iova_get_pad_size(unsigned int size, unsigned int limit_pfn)
 {
-       unsigned int pad_size = 0;
-       unsigned int order = ilog2(size);
-
-       if (order)
-               pad_size = (limit_pfn + 1) % (1 << order);
-
-       return pad_size;
+       return (limit_pfn + 1 - size) & (__roundup_pow_of_two(size) - 1);
 }
 
 static int __alloc_and_insert_iova_range(struct iova_domain *iovad,
@@ -242,6 +205,57 @@ 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;
+}
+EXPORT_SYMBOL_GPL(iova_cache_get);
+
+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);
+}
+EXPORT_SYMBOL_GPL(iova_cache_put);
+
 /**
  * alloc_iova - allocates an iova
  * @iovad: - iova domain in question
@@ -265,12 +279,6 @@ alloc_iova(struct iova_domain *iovad, unsigned long size,
        if (!new_iova)
                return NULL;
 
-       /* If size aligned is set then round the size to
-        * to next power of two.
-        */
-       if (size_aligned)
-               size = __roundup_pow_of_two(size);
-
        ret = __alloc_and_insert_iova_range(iovad, size, limit_pfn,
                        new_iova, size_aligned);
 
@@ -281,6 +289,7 @@ alloc_iova(struct iova_domain *iovad, unsigned long size,
 
        return new_iova;
 }
+EXPORT_SYMBOL_GPL(alloc_iova);
 
 /**
  * find_iova - find's an iova for a given pfn
@@ -321,6 +330,7 @@ struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn)
        spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
        return NULL;
 }
+EXPORT_SYMBOL_GPL(find_iova);
 
 /**
  * __free_iova - frees the given iova
@@ -339,6 +349,7 @@ __free_iova(struct iova_domain *iovad, struct iova *iova)
        spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
        free_iova_mem(iova);
 }
+EXPORT_SYMBOL_GPL(__free_iova);
 
 /**
  * free_iova - finds and frees the iova for a given pfn
@@ -356,6 +367,7 @@ free_iova(struct iova_domain *iovad, unsigned long pfn)
                __free_iova(iovad, iova);
 
 }
+EXPORT_SYMBOL_GPL(free_iova);
 
 /**
  * put_iova_domain - destroys the iova doamin
@@ -378,6 +390,7 @@ void put_iova_domain(struct iova_domain *iovad)
        }
        spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
 }
+EXPORT_SYMBOL_GPL(put_iova_domain);
 
 static int
 __is_range_overlap(struct rb_node *node,
@@ -467,6 +480,7 @@ finish:
        spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
        return iova;
 }
+EXPORT_SYMBOL_GPL(reserve_iova);
 
 /**
  * copy_reserved_iova - copies the reserved between domains
@@ -493,6 +507,7 @@ copy_reserved_iova(struct iova_domain *from, struct iova_domain *to)
        }
        spin_unlock_irqrestore(&from->iova_rbtree_lock, flags);
 }
+EXPORT_SYMBOL_GPL(copy_reserved_iova);
 
 struct iova *
 split_and_remove_iova(struct iova_domain *iovad, struct iova *iova,
@@ -534,3 +549,6 @@ error:
                free_iova_mem(prev);
        return NULL;
 }
+
+MODULE_AUTHOR("Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>");
+MODULE_LICENSE("GPL");