[PATCH 11/20] arm64: introduce binfmt_elf32.c

Yury Norov
2017-03-01T19:19:19Z

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@caviumnetworks.com>
---
arch/arm64/Kconfig | 1 -
arch/arm64/include/asm/elf.h | 22 ++--------------------
arch/arm64/include/asm/hwcap.h | 2 --
arch/arm64/kernel/Makefile | 2 +-
arch/arm64/kernel/binfmt_elf32.c | 32 ++++++++++++++++++++++++++++++++
5 files changed, 35 insertions(+), 24 deletions(-)
create mode 100644 arch/arm64/kernel/binfmt_elf32.c

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index d35cea4..d059063 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1049,7 +1049,6 @@ config AARCH32_EL0
bool "Kernel support for 32-bit EL0"
def_bool y
depends on ARM64_4K_PAGES || EXPERT
- select COMPAT_BINFMT_ELF if BINFMT_ELF
select COMPAT
select HAVE_UID16
select OLD_SIGSUSPEND3
diff --git a/arch/arm64/include/asm/elf.h b/arch/arm64/include/asm/elf.h
index a0188e2..453e0da 100644
--- a/arch/arm64/include/asm/elf.h
+++ b/arch/arm64/include/asm/elf.h
@@ -176,30 +176,12 @@ extern int arch_setup_additional_pages(struct linux_binprm *bprm,

#define COMPAT_ELF_ET_DYN_BASE (2 * TASK_SIZE_32 / 3)

+#ifdef CONFIG_AARCH32_EL0
/* AArch32 registers. */
#define COMPAT_ELF_NGREG 18
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) (system_supports_32bit_el0() && \
- ((x)->e_machine == EM_ARM) && \
- ((x)->e_flags & EF_ARM_EABI_MASK))
-
-#define compat_start_thread compat_start_thread
-#define COMPAT_SET_PERSONALITY(ex) \
-({ \
- set_bit(TIF_32BIT, &current->mm->context.flags); \
- clear_thread_flag(TIF_32BIT_AARCH64); \
- set_thread_flag(TIF_32BIT); \
- })
-#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_AARCH32_EL0 */
#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 b688bcd..aeaf474 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -28,7 +28,7 @@ $(obj)/%.stub.o: $(obj)/%.o FORCE
$(call if_changed,objcopy)

arm64-obj-$(CONFIG_AARCH32_EL0) += sys32.o kuser32.o signal32.o \
- sys_compat.o entry32.o
+ sys_compat.o entry32.o binfmt_elf32.o
arm64-obj-$(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..7c38a22
--- /dev/null
+++ b/arch/arm64/kernel/binfmt_elf32.c
@@ -0,0 +1,32 @@
+/*
+ * Support for AArch32 Linux ELF binaries.
+ */
+
+/* AArch32 EABI. */
+#define EF_ARM_EABI_MASK 0xff000000
+
+#define compat_start_thread compat_start_thread
+#define COMPAT_SET_PERSONALITY(ex) \
+({ \
+ set_bit(TIF_32BIT, &current->mm->context.flags); \
+ clear_thread_flag(TIF_32BIT_AARCH64); \
+ set_thread_flag(TIF_32BIT); \
+ })
+
+#define COMPAT_ARCH_DLINFO
+#define COMPAT_ELF_HWCAP (compat_elf_hwcap)
+#define COMPAT_ELF_HWCAP2 (compat_elf_hwcap2)
+
+#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);
+
+/* AArch32 EABI. */
+#define compat_elf_check_arch(x) (system_supports_32bit_el0() && \
+ ((x)->e_machine == EM_ARM) && \
+ ((x)->e_flags & EF_ARM_EABI_MASK))
+
+
+#include "../../../fs/compat_binfmt_elf.c"
--
2.7.4