[PATCH v9 01/16] ARM: add mem_type prot_pte accessor

[Christoffer Dall <c.dall@virtualopensystems.com>]

From: Marc Zyngier <marc.zyngier@arm.com>

The KVM hypervisor mmu code requires requires access to the
mem_type prot_pte field when setting up page tables pointing
to a device. Unfortunately, the mem_type structure is opaque.

Add an accessor (get_mem_type_prot_pte()) to retrieve the
prot_pte value.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
---
 arch/arm/include/asm/mach/map.h |    1 +
 arch/arm/mm/mmu.c               |    6 ++++++
 2 files changed, 7 insertions(+)

diff --git a/arch/arm/include/asm/mach/map.h b/arch/arm/include/asm/mach/map.h
index a6efcdd..3787c9f 100644
--- a/arch/arm/include/asm/mach/map.h
+++ b/arch/arm/include/asm/mach/map.h
@@ -37,6 +37,7 @@ extern void iotable_init(struct map_desc *, int);
 
 struct mem_type;
 extern const struct mem_type *get_mem_type(unsigned int type);
+extern pteval_t get_mem_type_prot_pte(unsigned int type);
 /*
  * external interface to remap single page with appropriate type
  */
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index e5dad60..f7439e7 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -301,6 +301,12 @@ const struct mem_type *get_mem_type(unsigned int type)
 }
 EXPORT_SYMBOL(get_mem_type);
 
+pteval_t get_mem_type_prot_pte(unsigned int type)
+{
+	return get_mem_type(type)->prot_pte;
+}
+EXPORT_SYMBOL(get_mem_type_prot_pte);
+
 /*
  * Adjust the PMD section entries according to the CPU in use.
  */