[PATCH 1/5] linux/types: import __aligned_x64 from the kernel

[Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>]

need it by upcoming EFI GPT support

Cc: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
---
 include/linux/types.h |   13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/include/linux/types.h b/include/linux/types.h
index 76c6b67..14f8315 100644
--- a/include/linux/types.h
+++ b/include/linux/types.h
@@ -142,6 +142,19 @@ typedef __u64 __bitwise __be64;
 typedef __u16 __bitwise __sum16;
 typedef __u32 __bitwise __wsum;
 
+/*
+ * aligned_u64 should be used in defining kernel<->userspace ABIs to avoid
+ * common 32/64-bit compat problems.
+ * 64-bit values align to 4-byte boundaries on x86_32 (and possibly other
+ * architectures) and to 8-byte boundaries on 64-bit architectures.  The new
+ * aligned_64 type enforces 8-byte alignment so that structs containing
+ * aligned_64 values have the same alignment on 32-bit and 64-bit architectures.
+ * No conversions are necessary between 32-bit user-space and a 64-bit kernel.
+ */
+#define __aligned_u64 __u64 __attribute__((aligned(8)))
+#define __aligned_be64 __be64 __attribute__((aligned(8)))
+#define __aligned_le64 __le64 __attribute__((aligned(8)))
+
 #ifdef CONFIG_PHYS_ADDR_T_64BIT
 typedef u64 phys_addr_t;
 typedef u64 phys_size_t;
-- 
1.7.10.4


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