[PATCH 15/23] arm64: introduce binfmt_elf32.c

From: Yury Norov
Date: Mon May 23 2016 - 20:09:38 EST


As we support more than one compat formats, it looks more reasonable
to not use fs/compat_binfmt.c. Custom binfmt_elf32.c allows to move aarch32
specific definitions there and make code more maintainable and readable.

Signed-off-by: Yury Norov <ynorov@xxxxxxxxxxxxxxxxxx>
---
arch/arm64/Kconfig | 1 -
arch/arm64/include/asm/elf.h | 24 ------------------------
arch/arm64/include/asm/hwcap.h | 2 --
arch/arm64/kernel/Makefile | 2 +-
arch/arm64/kernel/binfmt_elf32.c | 33 +++++++++++++++++++++++++++++++++
5 files changed, 34 insertions(+), 28 deletions(-)
create mode 100644 arch/arm64/kernel/binfmt_elf32.c

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index ede9b2e..0bb7adc 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -932,7 +932,6 @@ config AARCH32_EL0
bool "Kernel support for 32-bit EL0"
def_bool y
depends on ARM64_4K_PAGES || EXPERT
- select COMPAT_BINFMT_ELF
select HAVE_UID16
select OLD_SIGSUSPEND3
select COMPAT_OLD_SIGACTION
diff --git a/arch/arm64/include/asm/elf.h b/arch/arm64/include/asm/elf.h
index e18bb8a..7a39683 100644
--- a/arch/arm64/include/asm/elf.h
+++ b/arch/arm64/include/asm/elf.h
@@ -166,12 +166,6 @@ extern int arch_setup_additional_pages(struct linux_binprm *bprm,

#ifdef CONFIG_COMPAT

-#ifdef __AARCH64EB__
-#define COMPAT_ELF_PLATFORM ("v8b")
-#else
-#define COMPAT_ELF_PLATFORM ("v8l")
-#endif
-
#define COMPAT_ELF_ET_DYN_BASE (2 * TASK_SIZE_32 / 3)

/* AArch32 registers. */
@@ -179,24 +173,6 @@ extern int arch_setup_additional_pages(struct linux_binprm *bprm,
typedef unsigned int compat_elf_greg_t;
typedef compat_elf_greg_t compat_elf_gregset_t[COMPAT_ELF_NGREG];

-/* AArch32 EABI. */
-#define EF_ARM_EABI_MASK 0xff000000
-#define compat_elf_check_arch(x) (((x)->e_machine == EM_ARM) && \
- ((x)->e_flags & EF_ARM_EABI_MASK))
-
-#define compat_start_thread compat_start_thread
-#define COMPAT_SET_PERSONALITY(ex) \
-do { \
- clear_thread_flag(TIF_32BIT_AARCH64); \
- set_thread_flag(TIF_32BIT); \
-} while (0)
-
-#define COMPAT_ARCH_DLINFO
-extern int aarch32_setup_vectors_page(struct linux_binprm *bprm,
- int uses_interp);
-#define compat_arch_setup_additional_pages \
- aarch32_setup_vectors_page
-
#endif /* CONFIG_COMPAT */

#endif /* !__ASSEMBLY__ */
diff --git a/arch/arm64/include/asm/hwcap.h b/arch/arm64/include/asm/hwcap.h
index 2c7fc5d..99dfd92 100644
--- a/arch/arm64/include/asm/hwcap.h
+++ b/arch/arm64/include/asm/hwcap.h
@@ -47,8 +47,6 @@
#define ELF_HWCAP (elf_hwcap)

#ifdef CONFIG_AARCH32_EL0
-#define COMPAT_ELF_HWCAP (compat_elf_hwcap)
-#define COMPAT_ELF_HWCAP2 (compat_elf_hwcap2)
extern unsigned int compat_elf_hwcap, compat_elf_hwcap2;
#endif

diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index 75dd250..6bc9738 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -27,7 +27,7 @@ $(obj)/%.stub.o: $(obj)/%.o FORCE

arm64-obj-$(CONFIG_AARCH32_EL0) += sys32.o kuser32.o signal32.o \
sys_compat.o entry32.o \
- ../../arm/kernel/opcodes.o
+ ../../arm/kernel/opcodes.o binfmt_elf32.o
arm64-obj-$(CONFIG_FUNCTION_TRACER) += ftrace.o entry-ftrace.o
arm64-obj-$(CONFIG_MODULES) += arm64ksyms.o module.o
arm64-obj-$(CONFIG_ARM64_MODULE_PLTS) += module-plts.o
diff --git a/arch/arm64/kernel/binfmt_elf32.c b/arch/arm64/kernel/binfmt_elf32.c
new file mode 100644
index 0000000..5487872
--- /dev/null
+++ b/arch/arm64/kernel/binfmt_elf32.c
@@ -0,0 +1,33 @@
+/*
+ * Support for AArch32 Linux ELF binaries.
+ */
+
+/* AArch32 EABI. */
+#define EF_ARM_EABI_MASK 0xff000000
+#define compat_elf_check_arch(x) (((x)->e_machine == EM_ARM) && \
+ ((x)->e_flags & EF_ARM_EABI_MASK))
+
+#define compat_start_thread compat_start_thread
+#define COMPAT_SET_PERSONALITY(ex) \
+do { \
+ clear_thread_flag(TIF_32BIT_AARCH64); \
+ set_thread_flag(TIF_32BIT); \
+} while (0)
+
+#define COMPAT_ARCH_DLINFO
+#define COMPAT_ELF_HWCAP (compat_elf_hwcap)
+#define COMPAT_ELF_HWCAP2 (compat_elf_hwcap2)
+
+#ifdef __AARCH64EB__
+#define COMPAT_ELF_PLATFORM ("v8b")
+#else
+#define COMPAT_ELF_PLATFORM ("v8l")
+#endif
+
+#define compat_arch_setup_additional_pages \
+ aarch32_setup_vectors_page
+struct linux_binprm;
+extern int aarch32_setup_vectors_page(struct linux_binprm *bprm,
+ int uses_interp);
+
+#include "../../../fs/compat_binfmt_elf.c"
--
2.5.0