iommu: Make IOVA domain low limit flexible
To share the IOVA allocator with other architectures, it needs to
accommodate more general aperture restrictions; move the lower limit
from a compile-time constant to a runtime domain property to allow
IOVA domains with different requirements to co-exist.
Also reword the slightly unclear description of alloc_iova since we're
touching it anyway.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
diff --git a/include/linux/iova.h b/include/linux/iova.h
index ad0507c..591b196 100644
--- a/include/linux/iova.h
+++ b/include/linux/iova.h
@@ -16,9 +16,6 @@
#include <linux/rbtree.h>
#include <linux/dma-mapping.h>
-/* IO virtual address start page frame number */
-#define IOVA_START_PFN (1)
-
/* iova structure */
struct iova {
struct rb_node node;
@@ -31,6 +28,7 @@
spinlock_t iova_rbtree_lock; /* Lock to protect update of rbtree */
struct rb_root rbroot; /* iova domain rbtree root */
struct rb_node *cached32_node; /* Save last alloced node */
+ unsigned long start_pfn; /* Lower limit for this domain */
unsigned long dma_32bit_pfn;
};
@@ -52,7 +50,8 @@
struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo,
unsigned long pfn_hi);
void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to);
-void init_iova_domain(struct iova_domain *iovad, unsigned long pfn_32bit);
+void init_iova_domain(struct iova_domain *iovad, unsigned long start_pfn,
+ unsigned long pfn_32bit);
struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn);
void put_iova_domain(struct iova_domain *iovad);
struct iova *split_and_remove_iova(struct iova_domain *iovad,