[PATCH v3] libfdt: define INT32_MAX and UINT32_MAX in libfdt_env.h

Masahiro Yamada yamada.masahiro at socionext.com
Wed Nov 13 18:12:02 AEDT 2019


The DTC v1.5.1 added references to (U)INT32_MAX.

This is no problem for user-space programs since <stdint.h> defines
(U)INT32_MAX along with (u)int32_t.

For the kernel space, libfdt_env.h needs to be adjusted before we
pull in the changes.

In the kernel, we usually use s/u32 instead of (u)int32_t for the
fixed-width types.

Accordingly, we already have S/U32_MAX for their max values.
So, we should not add (U)INT32_MAX to <linux/limits.h> any more.

Instead, add them to the in-kernel libfdt_env.h to compile the
latest libfdt.

Signed-off-by: Masahiro Yamada <yamada.masahiro at socionext.com>
---

My initial plan was to change this in a series of 3 patches
since it is clean, and reduces the code.

[1/3] https://lore.kernel.org/patchwork/patch/1147095/
[2/3] https://lore.kernel.org/patchwork/patch/1147096/
[3/3] https://lore.kernel.org/patchwork/patch/1147097/

1/3 is stuck in the license bikeshed.

For 2/3, I have not been able to get Ack from Russell.

So, I chose a straight-forward fixup.


Changes in v3:
 - Resend as a single patch

 arch/arm/boot/compressed/libfdt_env.h | 4 +++-
 arch/powerpc/boot/libfdt_env.h        | 2 ++
 include/linux/libfdt_env.h            | 3 +++
 3 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/compressed/libfdt_env.h b/arch/arm/boot/compressed/libfdt_env.h
index b36c0289a308..6a0f1f524466 100644
--- a/arch/arm/boot/compressed/libfdt_env.h
+++ b/arch/arm/boot/compressed/libfdt_env.h
@@ -2,11 +2,13 @@
 #ifndef _ARM_LIBFDT_ENV_H
 #define _ARM_LIBFDT_ENV_H
 
+#include <linux/limits.h>
 #include <linux/types.h>
 #include <linux/string.h>
 #include <asm/byteorder.h>
 
-#define INT_MAX			((int)(~0U>>1))
+#define INT32_MAX	S32_MAX
+#define UINT32_MAX	U32_MAX
 
 typedef __be16 fdt16_t;
 typedef __be32 fdt32_t;
diff --git a/arch/powerpc/boot/libfdt_env.h b/arch/powerpc/boot/libfdt_env.h
index 2abc8e83b95e..9757d4f6331e 100644
--- a/arch/powerpc/boot/libfdt_env.h
+++ b/arch/powerpc/boot/libfdt_env.h
@@ -6,6 +6,8 @@
 #include <string.h>
 
 #define INT_MAX			((int)(~0U>>1))
+#define UINT32_MAX		((u32)~0U)
+#define INT32_MAX		((s32)(UINT32_MAX >> 1))
 
 #include "of.h"
 
diff --git a/include/linux/libfdt_env.h b/include/linux/libfdt_env.h
index edb0f0c30904..1adf54aad2df 100644
--- a/include/linux/libfdt_env.h
+++ b/include/linux/libfdt_env.h
@@ -7,6 +7,9 @@
 
 #include <asm/byteorder.h>
 
+#define INT32_MAX	S32_MAX
+#define UINT32_MAX	U32_MAX
+
 typedef __be16 fdt16_t;
 typedef __be32 fdt32_t;
 typedef __be64 fdt64_t;
-- 
2.17.1



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