diff options
| -rw-r--r-- | arch/arm64/kernel/vdso32/.gitignore | 2 | ||||
| -rw-r--r-- | arch/arm64/kernel/vdso32/Makefile | 172 | ||||
| -rw-r--r-- | arch/arm64/kernel/vdso32/compiler.h | 120 | ||||
| -rw-r--r-- | arch/arm64/kernel/vdso32/datapage.h | 1 | ||||
| -rw-r--r-- | arch/arm64/kernel/vdso32/sigreturn.S | 76 | ||||
| -rw-r--r-- | arch/arm64/kernel/vdso32/vdso.S | 32 | ||||
| -rw-r--r-- | arch/arm64/kernel/vdso32/vdso.lds.S | 95 | ||||
| -rw-r--r-- | arch/arm64/kernel/vdso32/vgettimeofday.c | 3 |
8 files changed, 501 insertions, 0 deletions
diff --git a/arch/arm64/kernel/vdso32/.gitignore b/arch/arm64/kernel/vdso32/.gitignore new file mode 100644 index 000000000000..4fea950fa5ed --- /dev/null +++ b/arch/arm64/kernel/vdso32/.gitignore @@ -0,0 +1,2 @@ +vdso.lds +vdso.so.raw diff --git a/arch/arm64/kernel/vdso32/Makefile b/arch/arm64/kernel/vdso32/Makefile new file mode 100644 index 000000000000..6d44d972e89d --- /dev/null +++ b/arch/arm64/kernel/vdso32/Makefile @@ -0,0 +1,172 @@ +# +# Building a vDSO image for AArch32. +# +# Author: Kevin Brodsky <kevin.brodsky@arm.com> +# A mix between the arm64 and arm vDSO Makefiles. + +ifeq ($(cc-name),clang) + CC_ARM32 := $(cc-name) $(CLANG_TARGET_ARM32) -no-integrated-as +else + CC_ARM32 := $(CROSS_COMPILE_ARM32)$(cc-name) +endif + +# Same as cc-*option, but using CC_ARM32 instead of CC +cc32-option = $(call try-run,\ + $(CC_ARM32) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2)) +cc32-disable-warning = $(call try-run,\ + $(CC_ARM32) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1))) +cc32-ldoption = $(call try-run,\ + $(CC_ARM32) $(1) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2)) + +# We cannot use the global flags to compile the vDSO files, the main reason +# being that the 32-bit compiler may be older than the main (64-bit) compiler +# and therefore may not understand flags set using $(cc-option ...). Besides, +# arch-specific options should be taken from the arm Makefile instead of the +# arm64 one. +# As a result we set our own flags here. + +# From top-level Makefile +# NOSTDINC_FLAGS +VDSO_CPPFLAGS := -nostdinc -isystem $(shell $(CC_ARM32) -print-file-name=include) +VDSO_CPPFLAGS += $(LINUXINCLUDE) +VDSO_CPPFLAGS += $(KBUILD_CPPFLAGS) + +# Common C and assembly flags +# From top-level Makefile +VDSO_CAFLAGS := $(VDSO_CPPFLAGS) +VDSO_CAFLAGS += $(call cc32-option,-fno-PIE) +ifdef CONFIG_DEBUG_INFO +VDSO_CAFLAGS += -g +endif +ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC_ARM32)), y) +VDSO_CAFLAGS += -DCC_HAVE_ASM_GOTO +endif + +# From arm Makefile +VDSO_CAFLAGS += $(call cc32-option,-fno-dwarf2-cfi-asm) +VDSO_CAFLAGS += -mabi=aapcs-linux -mfloat-abi=soft +ifeq ($(CONFIG_CPU_BIG_ENDIAN), y) +VDSO_CAFLAGS += -mbig-endian +else +VDSO_CAFLAGS += -mlittle-endian +endif + +# From arm vDSO Makefile +VDSO_CAFLAGS += -fPIC -fno-builtin -fno-stack-protector +VDSO_CAFLAGS += -DDISABLE_BRANCH_PROFILING + +# Try to compile for ARMv8. If the compiler is too old and doesn't support it, +# fall back to v7. There is no easy way to check for what architecture the code +# is being compiled, so define a macro specifying that (see arch/arm/Makefile). +VDSO_CAFLAGS += $(call cc32-option,-march=armv8-a -D__LINUX_ARM_ARCH__=8,\ + -march=armv7-a -D__LINUX_ARM_ARCH__=7) + +VDSO_CFLAGS := $(VDSO_CAFLAGS) +# KBUILD_CFLAGS from top-level Makefile +VDSO_CFLAGS += -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \ + -fno-strict-aliasing -fno-common \ + -Werror-implicit-function-declaration \ + -Wno-format-security \ + -std=gnu89 +VDSO_CFLAGS += -O2 +# Some useful compiler-dependent flags from top-level Makefile +VDSO_CFLAGS += $(call cc32-option,-Wdeclaration-after-statement,) +VDSO_CFLAGS += $(call cc32-option,-Wno-pointer-sign) +VDSO_CFLAGS += $(call cc32-option,-fno-strict-overflow) +VDSO_CFLAGS += $(call cc32-option,-Werror=strict-prototypes) +VDSO_CFLAGS += $(call cc32-option,-Werror=date-time) +VDSO_CFLAGS += $(call cc32-option,-Werror=incompatible-pointer-types) + +# The 32-bit compiler does not provide 128-bit integers, which are used in +# some headers that are indirectly included from the vDSO code. +# This hack makes the compiler happy and should trigger a warning/error if +# variables of such type are referenced. +VDSO_CFLAGS += -D__uint128_t='void*' +# Silence some warnings coming from headers that operate on long's +# (on GCC 4.8 or older, there is unfortunately no way to silence this warning) +VDSO_CFLAGS += $(call cc32-disable-warning,shift-count-overflow) +VDSO_CFLAGS += -Wno-int-to-pointer-cast + +VDSO_AFLAGS := $(VDSO_CAFLAGS) +VDSO_AFLAGS += -D__ASSEMBLY__ + +VDSO_LDFLAGS := $(VDSO_CPPFLAGS) +# From arm vDSO Makefile +VDSO_LDFLAGS += -Wl,-Bsymbolic -Wl,--no-undefined -Wl,-soname=linux-vdso.so.1 +VDSO_LDFLAGS += -Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096 +VDSO_LDFLAGS += -nostdlib -shared -mfloat-abi=soft +VDSO_LDFLAGS += $(call cc32-ldoption,-Wl$(comma)--hash-style=sysv) +VDSO_LDFLAGS += $(call cc32-ldoption,-Wl$(comma)--build-id) +VDSO_LDFLAGS += $(call cc32-ldoption,-fuse-ld=bfd) + + +# Borrow vdsomunge.c from the arm vDSO +# We have to use a relative path because scripts/Makefile.host prefixes +# $(hostprogs-y) with $(obj) +munge := ../../../arm/vdso/vdsomunge +hostprogs-y := $(munge) + +c-obj-vdso := vgettimeofday.o +asm-obj-vdso := sigreturn.o + +# Build rules +targets := $(c-obj-vdso) $(asm-obj-vdso) vdso.so vdso.so.dbg vdso.so.raw +c-obj-vdso := $(addprefix $(obj)/, $(c-obj-vdso)) +asm-obj-vdso := $(addprefix $(obj)/, $(asm-obj-vdso)) +obj-vdso := $(c-obj-vdso) $(asm-obj-vdso) + +obj-y += vdso.o +extra-y += vdso.lds +CPPFLAGS_vdso.lds += -P -C -U$(ARCH) + +# Force dependency (vdso.s includes vdso.so through incbin) +$(obj)/vdso.o: $(obj)/vdso.so + +include/generated/vdso32-offsets.h: $(obj)/vdso.so.dbg FORCE + $(call if_changed,vdsosym) + +# Strip rule for vdso.so +$(obj)/vdso.so: OBJCOPYFLAGS := -S +$(obj)/vdso.so: $(obj)/vdso.so.dbg FORCE + $(call if_changed,objcopy) + +$(obj)/vdso.so.dbg: $(obj)/vdso.so.raw $(obj)/$(munge) FORCE + $(call if_changed,vdsomunge) + +# Link rule for the .so file, .lds has to be first +$(obj)/vdso.so.raw: $(src)/vdso.lds $(obj-vdso) FORCE + $(call if_changed,vdsold) + +# Compilation rules for the vDSO sources +$(filter-out vgettimeofday.o, $(c-obj-vdso)): %.o: %.c FORCE + $(call if_changed_dep,vdsocc) +$(asm-obj-vdso): %.o: %.S FORCE + $(call if_changed_dep,vdsoas) + +# Actual build commands +quiet_cmd_vdsold = VDSOL32 $@ + cmd_vdsold = $(CC_ARM32) -Wp,-MD,$(depfile) $(VDSO_LDFLAGS) \ + -Wl,-T $(filter %.lds,$^) $(filter %.o,$^) -o $@ +quiet_cmd_vdsocc = VDSOC32 $@ + cmd_vdsocc = $(CC_ARM32) -Wp,-MD,$(depfile) $(VDSO_CFLAGS) -c -o $@ $< +quiet_cmd_vdsoas = VDSOA32 $@ + cmd_vdsoas = $(CC_ARM32) -Wp,-MD,$(depfile) $(VDSO_AFLAGS) -c -o $@ $< + +quiet_cmd_vdsomunge = MUNGE $@ + cmd_vdsomunge = $(obj)/$(munge) $< $@ + +# Generate vDSO offsets using helper script (borrowed from the 64-bit vDSO) +gen-vdsosym := $(srctree)/$(src)/../vdso/gen_vdso_offsets.sh +quiet_cmd_vdsosym = VDSOSYM $@ +# The AArch64 nm should be able to read an AArch32 binary + cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@ + +# Install commands for the unstripped file +quiet_cmd_vdso_install = INSTALL $@ + cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/vdso32.so + +vdso.so: $(obj)/vdso.so.dbg + @mkdir -p $(MODLIB)/vdso + $(call cmd,vdso_install) + +vdso_install: vdso.so diff --git a/arch/arm64/kernel/vdso32/compiler.h b/arch/arm64/kernel/vdso32/compiler.h new file mode 100644 index 000000000000..a2ac3959518a --- /dev/null +++ b/arch/arm64/kernel/vdso32/compiler.h @@ -0,0 +1,120 @@ +/* + * Userspace implementations of fallback calls + * + * Copyright (C) 2017 Cavium, Inc. + * Copyright (C) 2012 ARM Limited + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + * Author: Will Deacon <will.deacon@arm.com> + * Rewriten into C by: Andrew Pinski <apinski@cavium.com> + */ + +#ifndef __VDSO_COMPILER_H +#define __VDSO_COMPILER_H + +#include <asm/barrier.h> /* for isb() & dmb() */ +#include <asm/param.h> /* for HZ */ +#include <asm/unistd32.h> +#include <linux/compiler.h> + +#ifdef CONFIG_ARM_ARCH_TIMER +#define ARCH_PROVIDES_TIMER +#endif + +/* can not include linux/time.h because of too much architectural cruft */ +#ifndef NSEC_PER_SEC +#define NSEC_PER_SEC 1000000000L +#endif + +/* can not include linux/jiffies.h because of too much architectural cruft */ +#ifndef TICK_NSEC +#define TICK_NSEC ((NSEC_PER_SEC+HZ/2)/HZ) +#endif + +/* can not include linux/hrtimer.h because of too much architectural cruft */ +#ifndef LOW_RES_NSEC +#define LOW_RES_NSEC TICK_NSEC +#ifdef ARCH_PROVIDES_TIMER +#ifdef CONFIG_HIGH_RES_TIMERS +# define HIGH_RES_NSEC 1 +# define MONOTONIC_RES_NSEC HIGH_RES_NSEC +#else +# define MONOTONIC_RES_NSEC LOW_RES_NSEC +#endif +#endif +#endif + +#define DEFINE_FALLBACK(name, type_arg1, name_arg1, type_arg2, name_arg2) \ +static notrace long name##_fallback(type_arg1 _##name_arg1, \ + type_arg2 _##name_arg2) \ +{ \ + register type_arg1 name_arg1 asm("r0") = _##name_arg1; \ + register type_arg2 name_arg2 asm("r1") = _##name_arg2; \ + register long ret asm ("r0"); \ + register long nr asm("r7") = __NR_##name; \ + \ + asm volatile( \ + " swi #0\n" \ + : "=r" (ret) \ + : "r" (name_arg1), "r" (name_arg2), "r" (nr) \ + : "memory"); \ + \ + return ret; \ +} + +/* + * AArch32 implementation of arch_counter_get_cntvct() suitable for vdso + */ +static __always_inline notrace u64 arch_vdso_read_counter(void) +{ + u64 res; + + /* Read the virtual counter. */ + isb(); + asm volatile("mrrc p15, 1, %Q0, %R0, c14" : "=r" (res)); + + return res; +} + +/* + * Can not include asm/processor.h to pick this up because of all the + * architectural components also included, so we open code a copy. + */ +static inline void cpu_relax(void) +{ + asm volatile("yield" ::: "memory"); +} + +#undef smp_rmb +#if __LINUX_ARM_ARCH__ >= 8 +#define smp_rmb() dmb(ishld) /* ok on ARMv8 */ +#else +#define smp_rmb() dmb(ish) /* ishld does not exist on ARMv7 */ +#endif + +/* Avoid unresolved references emitted by GCC */ + +void __aeabi_unwind_cpp_pr0(void) +{ +} + +void __aeabi_unwind_cpp_pr1(void) +{ +} + +void __aeabi_unwind_cpp_pr2(void) +{ +} + +#endif /* __VDSO_COMPILER_H */ diff --git a/arch/arm64/kernel/vdso32/datapage.h b/arch/arm64/kernel/vdso32/datapage.h new file mode 100644 index 000000000000..fe3e216d94d1 --- /dev/null +++ b/arch/arm64/kernel/vdso32/datapage.h @@ -0,0 +1 @@ +#include "../vdso/datapage.h" diff --git a/arch/arm64/kernel/vdso32/sigreturn.S b/arch/arm64/kernel/vdso32/sigreturn.S new file mode 100644 index 000000000000..14e5f9ca34f9 --- /dev/null +++ b/arch/arm64/kernel/vdso32/sigreturn.S @@ -0,0 +1,76 @@ +/* + * Sigreturn trampolines for returning from a signal when the SA_RESTORER + * flag is not set. + * + * Copyright (C) 2016 ARM Limited + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + * Based on glibc's arm sa_restorer. While this is not strictly necessary, we + * provide both A32 and T32 versions, in accordance with the arm sigreturn + * code. + */ + +#include <linux/linkage.h> +#include <asm/asm-offsets.h> +#include <asm/unistd32.h> + +.macro sigreturn_trampoline name, syscall, regs_offset + /* + * We provide directives for enabling stack unwinding through the + * trampoline. On arm, CFI directives are only used for debugging (and + * the vDSO is stripped of debug information), so only the arm-specific + * unwinding directives are useful here. + */ + .fnstart + .save {r0-r15} + .pad #\regs_offset + /* + * It is necessary to start the unwind tables at least one instruction + * before the trampoline, as the unwinder will assume that the signal + * handler has been called from the trampoline, that is just before + * where the signal handler returns (mov r7, ...). + */ + nop +ENTRY(\name) + mov r7, #\syscall + svc #0 + .fnend + /* + * We would like to use ENDPROC, but the macro uses @ which is a + * comment symbol for arm assemblers, so directly use .type with % + * instead. + */ + .type \name, %function +END(\name) +.endm + + .text + + .arm + sigreturn_trampoline __kernel_sigreturn_arm, \ + __NR_sigreturn, \ + COMPAT_SIGFRAME_REGS_OFFSET + + sigreturn_trampoline __kernel_rt_sigreturn_arm, \ + __NR_rt_sigreturn, \ + COMPAT_RT_SIGFRAME_REGS_OFFSET + + .thumb + sigreturn_trampoline __kernel_sigreturn_thumb, \ + __NR_sigreturn, \ + COMPAT_SIGFRAME_REGS_OFFSET + + sigreturn_trampoline __kernel_rt_sigreturn_thumb, \ + __NR_rt_sigreturn, \ + COMPAT_RT_SIGFRAME_REGS_OFFSET diff --git a/arch/arm64/kernel/vdso32/vdso.S b/arch/arm64/kernel/vdso32/vdso.S new file mode 100644 index 000000000000..fe19ff70eb76 --- /dev/null +++ b/arch/arm64/kernel/vdso32/vdso.S @@ -0,0 +1,32 @@ +/* + * Copyright (C) 2012 ARM Limited + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + * Author: Will Deacon <will.deacon@arm.com> + */ + +#include <linux/init.h> +#include <linux/linkage.h> +#include <linux/const.h> +#include <asm/page.h> + + .globl vdso32_start, vdso32_end + .section .rodata + .balign PAGE_SIZE +vdso32_start: + .incbin "arch/arm64/kernel/vdso32/vdso.so" + .balign PAGE_SIZE +vdso32_end: + + .previous diff --git a/arch/arm64/kernel/vdso32/vdso.lds.S b/arch/arm64/kernel/vdso32/vdso.lds.S new file mode 100644 index 000000000000..f95cb1c431fb --- /dev/null +++ b/arch/arm64/kernel/vdso32/vdso.lds.S @@ -0,0 +1,95 @@ +/* + * Adapted from arm64 version. + * + * GNU linker script for the VDSO library. + * + * Copyright (C) 2012 ARM Limited + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + * Author: Will Deacon <will.deacon@arm.com> + * Heavily based on the vDSO linker scripts for other archs. + */ + +#include <linux/const.h> +#include <asm/page.h> +#include <asm/vdso.h> + +OUTPUT_FORMAT("elf32-littlearm", "elf32-bigarm", "elf32-littlearm") +OUTPUT_ARCH(arm) + +SECTIONS +{ + PROVIDE_HIDDEN(_vdso_data = . - PAGE_SIZE); + . = VDSO_LBASE + SIZEOF_HEADERS; + + .hash : { *(.hash) } :text + .gnu.hash : { *(.gnu.hash) } + .dynsym : { *(.dynsym) } + .dynstr : { *(.dynstr) } + .gnu.version : { *(.gnu.version) } + .gnu.version_d : { *(.gnu.version_d) } + .gnu.version_r : { *(.gnu.version_r) } + + .note : { *(.note.*) } :text :note + + .dynamic : { *(.dynamic) } :text :dynamic + + .rodata : { *(.rodata*) } :text + + .text : { *(.text*) } :text =0xe7f001f2 + + .got : { *(.got) } + .rel.plt : { *(.rel.plt) } + + /DISCARD/ : { + *(.note.GNU-stack) + *(.data .data.* .gnu.linkonce.d.* .sdata*) + *(.bss .sbss .dynbss .dynsbss) + } +} + +/* + * We must supply the ELF program headers explicitly to get just one + * PT_LOAD segment, and set the flags explicitly to make segments read-only. + */ +PHDRS +{ + text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */ + dynamic PT_DYNAMIC FLAGS(4); /* PF_R */ + note PT_NOTE FLAGS(4); /* PF_R */ +} + +VERSION +{ + LINUX_2.6 { + global: + __vdso_clock_gettime; + __vdso_gettimeofday; + __vdso_clock_getres; + __vdso_time; + __kernel_sigreturn_arm; + __kernel_sigreturn_thumb; + __kernel_rt_sigreturn_arm; + __kernel_rt_sigreturn_thumb; + local: *; + }; +} + +/* + * Make the sigreturn code visible to the kernel. + */ +VDSO_compat_sigreturn_arm = __kernel_sigreturn_arm; +VDSO_compat_sigreturn_thumb = __kernel_sigreturn_thumb; +VDSO_compat_rt_sigreturn_arm = __kernel_rt_sigreturn_arm; +VDSO_compat_rt_sigreturn_thumb = __kernel_rt_sigreturn_thumb; diff --git a/arch/arm64/kernel/vdso32/vgettimeofday.c b/arch/arm64/kernel/vdso32/vgettimeofday.c new file mode 100644 index 000000000000..b73d4011993d --- /dev/null +++ b/arch/arm64/kernel/vdso32/vgettimeofday.c @@ -0,0 +1,3 @@ +#include "compiler.h" +#include "datapage.h" +#include "../../../../lib/vdso/vgettimeofday.c" |