1
linux/arch/riscv/include/asm/vdso.h

42 lines
965 B
C
Raw Normal View History

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2012 ARM Limited
* Copyright (C) 2014 Regents of the University of California
* Copyright (C) 2017 SiFive
*/
#ifndef _ASM_RISCV_VDSO_H
#define _ASM_RISCV_VDSO_H
/*
* All systems with an MMU have a VDSO, but systems without an MMU don't
* support shared libraries and therefore don't have one.
*/
#ifdef CONFIG_MMU
#define __VVAR_PAGES 2
#ifndef __ASSEMBLY__
#include <generated/vdso-offsets.h>
#define VDSO_SYMBOL(base, name) \
(void __user *)((unsigned long)(base) + __vdso_##name##_offset)
riscv: compat: vdso: Add COMPAT_VDSO base code implementation There is no vgettimeofday supported in rv32 that makes simple to generate rv32 vdso code which only needs riscv64 compiler. Other architectures need change compiler or -m (machine parameter) to support vdso32 compiling. If rv32 support vgettimeofday (which cause C compile) in future, we would add CROSS_COMPILE to support that makes more requirement on compiler enviornment. linux-rv64/arch/riscv/kernel/compat_vdso/compat_vdso.so.dbg: file format elf64-littleriscv Disassembly of section .text: 0000000000000800 <__vdso_rt_sigreturn>: 800: 08b00893 li a7,139 804: 00000073 ecall 808: 0000 unimp ... 000000000000080c <__vdso_getcpu>: 80c: 0a800893 li a7,168 810: 00000073 ecall 814: 8082 ret ... 0000000000000818 <__vdso_flush_icache>: 818: 10300893 li a7,259 81c: 00000073 ecall 820: 8082 ret linux-rv32/arch/riscv/kernel/vdso/vdso.so.dbg: file format elf32-littleriscv Disassembly of section .text: 00000800 <__vdso_rt_sigreturn>: 800: 08b00893 li a7,139 804: 00000073 ecall 808: 0000 unimp ... 0000080c <__vdso_getcpu>: 80c: 0a800893 li a7,168 810: 00000073 ecall 814: 8082 ret ... 00000818 <__vdso_flush_icache>: 818: 10300893 li a7,259 81c: 00000073 ecall 820: 8082 ret Finally, reuse all *.S from vdso in compat_vdso that makes implementation clear and readable. Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@kernel.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Link: https://lore.kernel.org/r/20220405071314.3225832-17-guoren@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-04-05 00:13:10 -07:00
#ifdef CONFIG_COMPAT
#include <generated/compat_vdso-offsets.h>
#define COMPAT_VDSO_SYMBOL(base, name) \
(void __user *)((unsigned long)(base) + compat__vdso_##name##_offset)
extern char compat_vdso_start[], compat_vdso_end[];
riscv: compat: vdso: Add COMPAT_VDSO base code implementation There is no vgettimeofday supported in rv32 that makes simple to generate rv32 vdso code which only needs riscv64 compiler. Other architectures need change compiler or -m (machine parameter) to support vdso32 compiling. If rv32 support vgettimeofday (which cause C compile) in future, we would add CROSS_COMPILE to support that makes more requirement on compiler enviornment. linux-rv64/arch/riscv/kernel/compat_vdso/compat_vdso.so.dbg: file format elf64-littleriscv Disassembly of section .text: 0000000000000800 <__vdso_rt_sigreturn>: 800: 08b00893 li a7,139 804: 00000073 ecall 808: 0000 unimp ... 000000000000080c <__vdso_getcpu>: 80c: 0a800893 li a7,168 810: 00000073 ecall 814: 8082 ret ... 0000000000000818 <__vdso_flush_icache>: 818: 10300893 li a7,259 81c: 00000073 ecall 820: 8082 ret linux-rv32/arch/riscv/kernel/vdso/vdso.so.dbg: file format elf32-littleriscv Disassembly of section .text: 00000800 <__vdso_rt_sigreturn>: 800: 08b00893 li a7,139 804: 00000073 ecall 808: 0000 unimp ... 0000080c <__vdso_getcpu>: 80c: 0a800893 li a7,168 810: 00000073 ecall 814: 8082 ret ... 00000818 <__vdso_flush_icache>: 818: 10300893 li a7,259 81c: 00000073 ecall 820: 8082 ret Finally, reuse all *.S from vdso in compat_vdso that makes implementation clear and readable. Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@kernel.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Link: https://lore.kernel.org/r/20220405071314.3225832-17-guoren@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-04-05 00:13:10 -07:00
#endif /* CONFIG_COMPAT */
extern char vdso_start[], vdso_end[];
#endif /* !__ASSEMBLY__ */
#endif /* CONFIG_MMU */
#endif /* _ASM_RISCV_VDSO_H */