Merge git://git.infradead.org/users/willy/linux-nvme

[cascardo/linux.git] / drivers / iommu / iova.c

diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c
index 67da6cf..f6b17e6 100644 (file)
--- a/drivers/iommu/iova.c
+++ b/drivers/iommu/iova.c
@@ -342,19 +342,30 @@ __is_range_overlap(struct rb_node *node,
        return 0;
 }
 
+static inline struct iova *
+alloc_and_init_iova(unsigned long pfn_lo, unsigned long pfn_hi)
+{
+       struct iova *iova;
+
+       iova = alloc_iova_mem();
+       if (iova) {
+               iova->pfn_lo = pfn_lo;
+               iova->pfn_hi = pfn_hi;
+       }
+
+       return iova;
+}
+
 static struct iova *
 __insert_new_range(struct iova_domain *iovad,
        unsigned long pfn_lo, unsigned long pfn_hi)
 {
        struct iova *iova;
 
-       iova = alloc_iova_mem();
-       if (!iova)
-               return iova;
+       iova = alloc_and_init_iova(pfn_lo, pfn_hi);
+       if (iova)
+               iova_insert_rbtree(&iovad->rbroot, iova);
 
-       iova->pfn_hi = pfn_hi;
-       iova->pfn_lo = pfn_lo;
-       iova_insert_rbtree(&iovad->rbroot, iova);
        return iova;
 }
 
@@ -433,3 +444,44 @@ copy_reserved_iova(struct iova_domain *from, struct iova_domain *to)
        }
        spin_unlock_irqrestore(&from->iova_rbtree_lock, flags);
 }
+
+struct iova *
+split_and_remove_iova(struct iova_domain *iovad, struct iova *iova,
+                     unsigned long pfn_lo, unsigned long pfn_hi)
+{
+       unsigned long flags;
+       struct iova *prev = NULL, *next = NULL;
+
+       spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
+       if (iova->pfn_lo < pfn_lo) {
+               prev = alloc_and_init_iova(iova->pfn_lo, pfn_lo - 1);
+               if (prev == NULL)
+                       goto error;
+       }
+       if (iova->pfn_hi > pfn_hi) {
+               next = alloc_and_init_iova(pfn_hi + 1, iova->pfn_hi);
+               if (next == NULL)
+                       goto error;
+       }
+
+       __cached_rbnode_delete_update(iovad, iova);
+       rb_erase(&iova->node, &iovad->rbroot);
+
+       if (prev) {
+               iova_insert_rbtree(&iovad->rbroot, prev);
+               iova->pfn_lo = pfn_lo;
+       }
+       if (next) {
+               iova_insert_rbtree(&iovad->rbroot, next);
+               iova->pfn_hi = pfn_hi;
+       }
+       spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
+
+       return iova;
+
+error:
+       spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
+       if (prev)
+               free_iova_mem(prev);
+       return NULL;
+}