[PATCH v2 14/34] ARM: mmu: implement MAP_FAULT

[Sascha Hauer]

MAP_FAULT can be used for the zero page to make it faulting.

Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
 arch/arm/cpu/mmu_32.c | 4 ++++
 arch/arm/cpu/mmu_64.c | 3 +++
 include/mmu.h         | 1 +
 3 files changed, 8 insertions(+)

diff --git a/arch/arm/cpu/mmu_32.c b/arch/arm/cpu/mmu_32.c
index 8ec21ee1d2..a1ecc49f03 100644
--- a/arch/arm/cpu/mmu_32.c
+++ b/arch/arm/cpu/mmu_32.c
@@ -178,6 +178,10 @@ int arch_remap_range(void *start, size_t size, unsigned flags)
 		pte_flags = pte_flags_uncached;
 		pgd_flags = pgd_flags_uncached;
 		break;
+	case MAP_FAULT:
+		pte_flags = 0x0;
+		pgd_flags = 0x0;
+		break;
 	case ARCH_MAP_WRITECOMBINE:
 		pte_flags = pte_flags_wc;
 		pgd_flags = pgd_flags_wc;
diff --git a/arch/arm/cpu/mmu_64.c b/arch/arm/cpu/mmu_64.c
index f43ac9a121..a22e0c81ab 100644
--- a/arch/arm/cpu/mmu_64.c
+++ b/arch/arm/cpu/mmu_64.c
@@ -154,6 +154,9 @@ int arch_remap_range(void *_start, size_t size, unsigned flags)
 	case MAP_UNCACHED:
 		attrs = attrs_uncached_mem();
 		break;
+	case MAP_FAULT:
+		attrs = 0x0;
+		break;
 	default:
 		return -EINVAL;
 	}
diff --git a/include/mmu.h b/include/mmu.h
index 2e23853df3..2326cb215a 100644
--- a/include/mmu.h
+++ b/include/mmu.h
@@ -4,6 +4,7 @@
 
 #define MAP_UNCACHED	0
 #define MAP_CACHED	1
+#define MAP_FAULT	2
 
 /*
  * Depending on the architecture the default mapping can be
-- 
2.39.2