diff options
Diffstat (limited to 'arch/riscv/kernel/vdso')
| -rw-r--r-- | arch/riscv/kernel/vdso/.gitignore | 2 | ||||
| -rw-r--r-- | arch/riscv/kernel/vdso/Makefile | 63 | ||||
| -rw-r--r-- | arch/riscv/kernel/vdso/rt_sigreturn.S | 24 | ||||
| -rw-r--r-- | arch/riscv/kernel/vdso/vdso.S | 27 | ||||
| -rw-r--r-- | arch/riscv/kernel/vdso/vdso.lds.S | 77 |
5 files changed, 193 insertions, 0 deletions
diff --git a/arch/riscv/kernel/vdso/.gitignore b/arch/riscv/kernel/vdso/.gitignore new file mode 100644 index 000000000000..97c2d69d0289 --- /dev/null +++ b/arch/riscv/kernel/vdso/.gitignore @@ -0,0 +1,2 @@ +vdso.lds +*.tmp diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile new file mode 100644 index 000000000000..523d0a8ac8db --- /dev/null +++ b/arch/riscv/kernel/vdso/Makefile @@ -0,0 +1,63 @@ +# Copied from arch/tile/kernel/vdso/Makefile + +# Symbols present in the vdso +vdso-syms = rt_sigreturn + +# Files to link into the vdso +obj-vdso = $(patsubst %, %.o, $(vdso-syms)) + +# 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 + +# Force dependency +$(obj)/vdso.o: $(obj)/vdso.so + +# link rule for the .so file, .lds has to be first +SYSCFLAGS_vdso.so.dbg = $(c_flags) +$(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso) FORCE + $(call if_changed,vdsold) + +# We also create a special relocatable object that should mirror the symbol +# table and layout of the linked DSO. With ld -R we can then refer to +# these symbols in the kernel code rather than hand-coded addresses. + +SYSCFLAGS_vdso.so.dbg = -shared -s -Wl,-soname=linux-vdso.so.1 \ + $(call cc-ldoption, -Wl$(comma)--hash-style=both) +$(obj)/vdso-dummy.o: $(src)/vdso.lds $(obj)/rt_sigreturn.o FORCE + $(call if_changed,vdsold) + +LDFLAGS_vdso-syms.o := -r -R +$(obj)/vdso-syms.o: $(obj)/vdso-dummy.o FORCE + $(call if_changed,ld) + +# strip rule for the .so file +$(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 +# Add -lgcc so rv32 gets static muldi3 and lshrdi3 definitions. +# Make sure only to export the intended __vdso_xxx symbol offsets. +quiet_cmd_vdsold = VDSOLD $@ + cmd_vdsold = $(CC) $(KCFLAGS) -nostdlib $(SYSCFLAGS_$(@F)) \ + -Wl,-T,$(filter-out FORCE,$^) -o $@.tmp -lgcc && \ + $(CROSS_COMPILE)objcopy \ + $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ + +# 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/riscv/kernel/vdso/rt_sigreturn.S b/arch/riscv/kernel/vdso/rt_sigreturn.S new file mode 100644 index 000000000000..f5aa3d72acfb --- /dev/null +++ b/arch/riscv/kernel/vdso/rt_sigreturn.S @@ -0,0 +1,24 @@ +/* + * Copyright (C) 2014 Regents of the University of California + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * 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. + */ + +#include <linux/linkage.h> +#include <asm/unistd.h> + + .text +ENTRY(__vdso_rt_sigreturn) + .cfi_startproc + .cfi_signal_frame + li a7, __NR_rt_sigreturn + scall + .cfi_endproc +ENDPROC(__vdso_rt_sigreturn) diff --git a/arch/riscv/kernel/vdso/vdso.S b/arch/riscv/kernel/vdso/vdso.S new file mode 100644 index 000000000000..7055de5f9174 --- /dev/null +++ b/arch/riscv/kernel/vdso/vdso.S @@ -0,0 +1,27 @@ +/* + * Copyright (C) 2014 Regents of the University of California + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * 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. + */ + +#include <linux/init.h> +#include <linux/linkage.h> +#include <asm/page.h> + + __PAGE_ALIGNED_DATA + + .globl vdso_start, vdso_end + .balign PAGE_SIZE +vdso_start: + .incbin "arch/riscv/kernel/vdso/vdso.so" + .balign PAGE_SIZE +vdso_end: + + .previous diff --git a/arch/riscv/kernel/vdso/vdso.lds.S b/arch/riscv/kernel/vdso/vdso.lds.S new file mode 100644 index 000000000000..8c9dce95c11d --- /dev/null +++ b/arch/riscv/kernel/vdso/vdso.lds.S @@ -0,0 +1,77 @@ +/* + * Copyright (C) 2012 Regents of the University of California + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * 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. + */ + +OUTPUT_ARCH(riscv) + +SECTIONS +{ + . = 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.*) } + + /* + * This linker script is used both with -r and with -shared. + * For the layouts to match, we need to skip more than enough + * space for the dynamic symbol table, etc. If this amount is + * insufficient, ld -shared will error; simply increase it here. + */ + . = 0x800; + .text : { *(.text .text.*) } :text + + .data : { + *(.got.plt) *(.got) + *(.data .data.* .gnu.linkonce.d.*) + *(.dynbss) + *(.bss .bss.* .gnu.linkonce.b.*) + } +} + +/* + * 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 */ + eh_frame_hdr PT_GNU_EH_FRAME; +} + +/* + * This controls what symbols we export from the DSO. + */ +VERSION +{ + LINUX_4.15 { + global: + __vdso_rt_sigreturn; + __vdso_cmpxchg32; + __vdso_cmpxchg64; + local: *; + }; +} |
