Add setjmp/longjmp functions for x86_64. The FPU control word and MXCSR control bits are preserved across calls.
Signed-off-by: Ivan Gorinov ivan.gorinov@intel.com --- arch/x86/cpu/x86_64/setjmp.S | 66 +++++++++++++++++++++++++++++++++++++++++++ arch/x86/cpu/x86_64/setjmp.c | 19 ------------- arch/x86/include/asm/setjmp.h | 19 +++++++++++++ 3 files changed, 85 insertions(+), 19 deletions(-) create mode 100644 arch/x86/cpu/x86_64/setjmp.S delete mode 100644 arch/x86/cpu/x86_64/setjmp.c
diff --git a/arch/x86/cpu/x86_64/setjmp.S b/arch/x86/cpu/x86_64/setjmp.S new file mode 100644 index 0000000..ef61a4a --- /dev/null +++ b/arch/x86/cpu/x86_64/setjmp.S @@ -0,0 +1,66 @@ +/* + * Copyright (C) 2018 Intel Corporation + * + * SPDX-License-Identifier: GPL-2.0+ + * + * See arch/x86/include/asm/setjmp.h for jmp_buf format + */ + +#include <linux/linkage.h> + +.text +.align 8 + +ENTRY(setjmp) + + pop %rcx + movq %rcx, (%rdi) /* Return address */ + movq %rsp, 8 (%rdi) + movq %rbp, 16 (%rdi) + movq %rbx, 24 (%rdi) + movq %r12, 32 (%rdi) + movq %r13, 40 (%rdi) + movq %r14, 48 (%rdi) + movq %r15, 56 (%rdi) + fnstcw 64 (%rdi) + stmxcsr 68 (%rdi) + xorq %rax, %rax /* Direct invocation returns 0 */ + jmpq *%rcx + +ENDPROC(setjmp) + +.align 8 + +ENTRY(longjmp) + + subq $8, %rsp + +/* Restore the control bits of MXCSR */ + + stmxcsr (%rsp) + movl $0x3f, %eax + andl %eax, (%rsp) + notl %eax + andl 68 (%rdi), %eax + orl %eax, (%rsp) + ldmxcsr (%rsp) + + fldcw 64 (%rdi) + + movq (%rdi), %rcx /* Return address */ + movq 8 (%rdi), %rsp + movq 16 (%rdi), %rbp + movq 24 (%rdi), %rbx + movq 32 (%rdi), %r12 + movq 40 (%rdi), %r13 + movq 48 (%rdi), %r14 + movq 56 (%rdi), %r15 + + movq %rsi, %rax /* Value to be returned by setjmp() */ + testq %rax, %rax /* cannot be 0 in this case */ + jnz 1f + incq %rax /* Return 1 instead */ +1: + jmpq *%rcx + +ENDPROC(longjmp) diff --git a/arch/x86/cpu/x86_64/setjmp.c b/arch/x86/cpu/x86_64/setjmp.c deleted file mode 100644 index 5d4a74a..0000000 --- a/arch/x86/cpu/x86_64/setjmp.c +++ /dev/null @@ -1,19 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0+ -/* - * Copyright (c) 2016 Google, Inc - */ - -#include <common.h> -#include <asm/setjmp.h> - -int setjmp(struct jmp_buf_data *jmp_buf) -{ - printf("WARNING: setjmp() is not supported\n"); - - return 0; -} - -void longjmp(struct jmp_buf_data *jmp_buf, int val) -{ - printf("WARNING: longjmp() is not supported\n"); -} diff --git a/arch/x86/include/asm/setjmp.h b/arch/x86/include/asm/setjmp.h index f25975f..eae33fb 100644 --- a/arch/x86/include/asm/setjmp.h +++ b/arch/x86/include/asm/setjmp.h @@ -8,6 +8,23 @@ #ifndef __setjmp_h #define __setjmp_h
+#ifdef CONFIG_X86_64 + +struct jmp_buf_data { + unsigned long __rip; + unsigned long __rsp; + unsigned long __rbp; + unsigned long __rbx; + unsigned long __r12; + unsigned long __r13; + unsigned long __r14; + unsigned long __r15; + unsigned int __fcw; + unsigned int __mxcsr; +}; + +#else + struct jmp_buf_data { unsigned int __ebx; unsigned int __esp; @@ -17,6 +34,8 @@ struct jmp_buf_data { unsigned int __eip; };
+#endif + int setjmp(struct jmp_buf_data *jmp_buf); void longjmp(struct jmp_buf_data *jmp_buf, int val);