From 87f3248cdb9aeac35129cb4337ce541a945cb35c Mon Sep 17 00:00:00 2001 From: Guo Ren Date: Mon, 4 Jan 2021 03:37:07 +0000 Subject: csky: Reconstruct VDSO framework Reconstruct vdso framework to support future vsyscall, vgettimeofday features. These are very important features to reduce system calls into the kernel for performance improvement. The patch is reference RISC-V's Signed-off-by: Guo Ren Cc: Palmer Dabbelt --- arch/csky/kernel/vdso/.gitignore | 4 +++ arch/csky/kernel/vdso/Makefile | 67 ++++++++++++++++++++++++++++++++++++ arch/csky/kernel/vdso/note.S | 12 +++++++ arch/csky/kernel/vdso/rt_sigreturn.S | 14 ++++++++ arch/csky/kernel/vdso/so2s.sh | 5 +++ arch/csky/kernel/vdso/vdso.S | 16 +++++++++ arch/csky/kernel/vdso/vdso.lds.S | 54 +++++++++++++++++++++++++++++ 7 files changed, 172 insertions(+) create mode 100644 arch/csky/kernel/vdso/.gitignore create mode 100644 arch/csky/kernel/vdso/Makefile create mode 100644 arch/csky/kernel/vdso/note.S create mode 100644 arch/csky/kernel/vdso/rt_sigreturn.S create mode 100755 arch/csky/kernel/vdso/so2s.sh create mode 100644 arch/csky/kernel/vdso/vdso.S create mode 100644 arch/csky/kernel/vdso/vdso.lds.S (limited to 'arch/csky/kernel/vdso') diff --git a/arch/csky/kernel/vdso/.gitignore b/arch/csky/kernel/vdso/.gitignore new file mode 100644 index 000000000000..3a19def868ec --- /dev/null +++ b/arch/csky/kernel/vdso/.gitignore @@ -0,0 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0-only +vdso.lds +*.tmp +vdso-syms.S diff --git a/arch/csky/kernel/vdso/Makefile b/arch/csky/kernel/vdso/Makefile new file mode 100644 index 000000000000..13ac549c6587 --- /dev/null +++ b/arch/csky/kernel/vdso/Makefile @@ -0,0 +1,67 @@ +# SPDX-License-Identifier: GPL-2.0-only + +# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before +# the inclusion of generic Makefile. +ARCH_REL_TYPE_ABS := R_CKCORE_ADDR32|R_CKCORE_JUMP_SLOT +include $(srctree)/lib/vdso/Makefile + +# Symbols present in the vdso +vdso-syms = rt_sigreturn + +# Files to link into the vdso +obj-vdso = $(patsubst %, %.o, $(vdso-syms)) note.o + +ccflags-y := -fno-stack-protector + +# Build rules +targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds vdso-dummy.o +obj-vdso := $(addprefix $(obj)/, $(obj-vdso)) + +obj-y += vdso.o vdso-syms.o +CPPFLAGS_vdso.lds += -P -C -U$(ARCH) + +# Disable gcov profiling for VDSO code +GCOV_PROFILE := n +KCOV_INSTRUMENT := n + +# Force dependency +$(obj)/vdso.o: $(obj)/vdso.so + +SYSCFLAGS_vdso.so.dbg = $(c_flags) +$(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso) FORCE + $(call if_changed,vdsold) +SYSCFLAGS_vdso.so.dbg = -shared -s -Wl,-soname=linux-vdso.so.1 \ + -Wl,--build-id=sha1 -Wl,--hash-style=both + +$(obj)/vdso-syms.S: $(obj)/vdso.so FORCE + $(call if_changed,so2s) + +# strip rule for the .so file +$(obj)/%.so: OBJCOPYFLAGS := -S +$(obj)/%.so: $(obj)/%.so.dbg FORCE + $(call if_changed,objcopy) + +# actual build commands +# The DSO images are built using a special linker script +# Make sure only to export the intended __vdso_xxx symbol offsets. +quiet_cmd_vdsold = VDSOLD $@ + cmd_vdsold = $(CC) $(KBUILD_CFLAGS) $(call cc-option, -no-pie) -nostdlib -nostartfiles $(SYSCFLAGS_$(@F)) \ + -Wl,-T,$(filter-out FORCE,$^) -o $@.tmp && \ + $(CROSS_COMPILE)objcopy \ + $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ && \ + rm $@.tmp + +# Extracts symbol offsets from the VDSO, converting them into an assembly file +# that contains the same symbols at the same offsets. +quiet_cmd_so2s = SO2S $@ + cmd_so2s = $(NM) -D $< | $(srctree)/$(src)/so2s.sh > $@ + +# install commands for the unstripped file +quiet_cmd_vdso_install = INSTALL $@ + cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@ + +vdso.so: $(obj)/vdso.so.dbg + @mkdir -p $(MODLIB)/vdso + $(call cmd,vdso_install) + +vdso_install: vdso.so diff --git a/arch/csky/kernel/vdso/note.S b/arch/csky/kernel/vdso/note.S new file mode 100644 index 000000000000..2a956c942211 --- /dev/null +++ b/arch/csky/kernel/vdso/note.S @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text. + * Here we can supply some information useful to userland. + */ + +#include +#include + +ELFNOTE_START(Linux, 0, "a") + .long LINUX_VERSION_CODE +ELFNOTE_END diff --git a/arch/csky/kernel/vdso/rt_sigreturn.S b/arch/csky/kernel/vdso/rt_sigreturn.S new file mode 100644 index 000000000000..0a6bd1216118 --- /dev/null +++ b/arch/csky/kernel/vdso/rt_sigreturn.S @@ -0,0 +1,14 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#include +#include +#include + + .text +ENTRY(__vdso_rt_sigreturn) + .cfi_startproc + .cfi_signal_frame + SET_SYSCALL_ID + trap 0 + .cfi_endproc +ENDPROC(__vdso_rt_sigreturn) diff --git a/arch/csky/kernel/vdso/so2s.sh b/arch/csky/kernel/vdso/so2s.sh new file mode 100755 index 000000000000..69da3d529c6d --- /dev/null +++ b/arch/csky/kernel/vdso/so2s.sh @@ -0,0 +1,5 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0+ + +sed 's!\([0-9a-f]*\) T \([a-z0-9_]*\)\(@@LINUX_5.10\)*!.global \2\n.set \2,0x\1!' \ +| grep '^\.' diff --git a/arch/csky/kernel/vdso/vdso.S b/arch/csky/kernel/vdso/vdso.S new file mode 100644 index 000000000000..5162ca069494 --- /dev/null +++ b/arch/csky/kernel/vdso/vdso.S @@ -0,0 +1,16 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#include +#include +#include + + __PAGE_ALIGNED_DATA + + .globl vdso_start, vdso_end + .balign PAGE_SIZE +vdso_start: + .incbin "arch/csky/kernel/vdso/vdso.so" + .balign PAGE_SIZE +vdso_end: + + .previous diff --git a/arch/csky/kernel/vdso/vdso.lds.S b/arch/csky/kernel/vdso/vdso.lds.S new file mode 100644 index 000000000000..8d226252d439 --- /dev/null +++ b/arch/csky/kernel/vdso/vdso.lds.S @@ -0,0 +1,54 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#include + +OUTPUT_ARCH(csky) + +SECTIONS +{ + PROVIDE(_vdso_data = . + PAGE_SIZE); + . = 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 + + .eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr + .eh_frame : { KEEP (*(.eh_frame)) } :text + + .rodata : { *(.rodata .rodata.* .gnu.linkonce.r.*) } + + . = 0x800; + .text : { *(.text .text.*) } :text + + .data : { + *(.got.plt) *(.got) + *(.data .data.* .gnu.linkonce.d.*) + *(.dynbss) + *(.bss .bss.* .gnu.linkonce.b.*) + } +} + +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 */ + eh_frame_hdr PT_GNU_EH_FRAME; +} + +VERSION +{ + LINUX_5.10 { + global: + __vdso_rt_sigreturn; + local: *; + }; +} -- cgit v1.3.1