[PATCH 1/2] Add __compat_aligned_s64 and __compat_aligned_u64

From: H.J. Lu
Date: Wed Aug 21 2013 - 15:35:56 EST

X32 uses the 32-bit compat layer for 32-bit kernel interface, which is
also used by ia32. But long long is 4-byte aligned for ia32 and 8-byte
aligned for x32. When the long long field in a system call struct has
different offsets between ia32 and x32 due to alignment padding, like
struct snd_ctl_elem_value in include/uapi/sound/asound.h, we need to
either add a special case for x32 or we can use 4-byte aligned long
long in the system call struct so that x32 can share the same compat
system cal with ia32. This patch adds __compat_aligned_s64 and
__compat_aligned_u64 to include/uapi/asm-generic/int-ll64.h. By
default, they are the same as __s64/__u64. It does the following

1. Add default __compat_aligned_s64/__compat_aligned_u64 to
2. Add arch/x86/include/asm/types.h for kernel internal use, which is the
same as before, i.e., <asm-generic/types.h>.
3. Change arch/x86/include/uapi/asm/types.h not to use the default
include/uapi/asm-generic/int-ll64.h. Instead, it has a modified copy
of include/uapi/asm-generic/int-ll64.h with 4-byte aligned
__compat_aligned_s64 and __compat_aligned_u64 for x32 and ia32.

When building x86 kernel, nothing is changed. The difference is
x32 can use 4-byte aligned long long for system calls so that it
can share the same 32-bit compat system call with ia32.

Signed-off-by: H.J. Lu <hjl.tools@xxxxxxxxx>
arch/x86/include/asm/types.h | 6 ++++++
arch/x86/include/uapi/asm/types.h | 35 ++++++++++++++++++++++++++++++++++-
include/uapi/asm-generic/int-ll64.h | 3 +++
3 files changed, 43 insertions(+), 1 deletion(-)
create mode 100644 arch/x86/include/asm/types.h

diff --git a/arch/x86/include/asm/types.h b/arch/x86/include/asm/types.h
new file mode 100644
index 0000000..8e8c23f
--- /dev/null
+++ b/arch/x86/include/asm/types.h
@@ -0,0 +1,6 @@
+#ifndef _ASM_X86_TYPES_H
+#define _ASM_X86_TYPES_H
+#include <asm-generic/types.h>
+#endif /* _ASM_X86_TYPES_H */
diff --git a/arch/x86/include/uapi/asm/types.h b/arch/x86/include/uapi/asm/types.h
index 8e8c23f..7d9c75a 100644
--- a/arch/x86/include/uapi/asm/types.h
+++ b/arch/x86/include/uapi/asm/types.h
@@ -1,6 +1,39 @@
#ifndef _ASM_X86_TYPES_H
#define _ASM_X86_TYPES_H

-#include <asm-generic/types.h>
+#include <asm/bitsperlong.h>
+#ifndef __ASSEMBLY__
+ * __xx is ok: it doesn't pollute the POSIX namespace. Use these in the
+ * header files exported to user space
+ */
+typedef __signed__ char __s8;
+typedef unsigned char __u8;
+typedef __signed__ short __s16;
+typedef unsigned short __u16;
+typedef __signed__ int __s32;
+typedef unsigned int __u32;
+#ifdef __GNUC__
+__extension__ typedef __signed__ long long __s64;
+__extension__ typedef unsigned long long __u64;
+typedef __signed__ long long __s64;
+typedef unsigned long long __u64;
+#if defined(__i386__) || defined(__ILP32__)
+typedef __s64 __attribute__((aligned(4))) __compat_aligned_s64;
+typedef __u64 __attribute__((aligned(4))) __compat_aligned_u64;
+typedef __s64 __compat_aligned_s64;
+typedef __u64 __compat_aligned_u64;
+#endif /* __ASSEMBLY__ */

#endif /* _ASM_X86_TYPES_H */
diff --git a/include/uapi/asm-generic/int-ll64.h b/include/uapi/asm-generic/int-ll64.h
index a8658b2..3306917 100644
--- a/include/uapi/asm-generic/int-ll64.h
+++ b/include/uapi/asm-generic/int-ll64.h
@@ -33,6 +33,9 @@ typedef __signed__ long long __s64;
typedef unsigned long long __u64;

+typedef __s64 __compat_aligned_s64;
+typedef __u64 __compat_aligned_u64;
#endif /* __ASSEMBLY__ */


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