From: Ingo Molnar Date: Wed, 3 Jun 2015 16:29:26 +0000 (+0200) Subject: x86/asm/entry: Move arch/x86/include/asm/calling.h to arch/x86/entry/ X-Git-Tag: v4.2-rc1~166^2^2~8^2~16 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=d36f947904dba0935a0e74dc9df2ef57caeb7d03;p=linux-2.6-block.git x86/asm/entry: Move arch/x86/include/asm/calling.h to arch/x86/entry/ asm/calling.h is private to the entry code, make this more apparent by moving it to the new arch/x86/entry/ directory. Cc: Borislav Petkov Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Thomas Gleixner Cc: Andy Lutomirski Cc: Denys Vlasenko Cc: Brian Gerst Cc: Peter Zijlstra Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar --- diff --git a/arch/x86/entry/calling.h b/arch/x86/entry/calling.h new file mode 100644 index 000000000000..f4e6308c4200 --- /dev/null +++ b/arch/x86/entry/calling.h @@ -0,0 +1,243 @@ +/* + + x86 function call convention, 64-bit: + ------------------------------------- + arguments | callee-saved | extra caller-saved | return + [callee-clobbered] | | [callee-clobbered] | + --------------------------------------------------------------------------- + rdi rsi rdx rcx r8-9 | rbx rbp [*] r12-15 | r10-11 | rax, rdx [**] + + ( rsp is obviously invariant across normal function calls. (gcc can 'merge' + functions when it sees tail-call optimization possibilities) rflags is + clobbered. Leftover arguments are passed over the stack frame.) + + [*] In the frame-pointers case rbp is fixed to the stack frame. + + [**] for struct return values wider than 64 bits the return convention is a + bit more complex: up to 128 bits width we return small structures + straight in rax, rdx. For structures larger than that (3 words or + larger) the caller puts a pointer to an on-stack return struct + [allocated in the caller's stack frame] into the first argument - i.e. + into rdi. All other arguments shift up by one in this case. + Fortunately this case is rare in the kernel. + +For 32-bit we have the following conventions - kernel is built with +-mregparm=3 and -freg-struct-return: + + x86 function calling convention, 32-bit: + ---------------------------------------- + arguments | callee-saved | extra caller-saved | return + [callee-clobbered] | | [callee-clobbered] | + ------------------------------------------------------------------------- + eax edx ecx | ebx edi esi ebp [*] | | eax, edx [**] + + ( here too esp is obviously invariant across normal function calls. eflags + is clobbered. Leftover arguments are passed over the stack frame. ) + + [*] In the frame-pointers case ebp is fixed to the stack frame. + + [**] We build with -freg-struct-return, which on 32-bit means similar + semantics as on 64-bit: edx can be used for a second return value + (i.e. covering integer and structure sizes up to 64 bits) - after that + it gets more complex and more expensive: 3-word or larger struct returns + get done in the caller's frame and the pointer to the return struct goes + into regparm0, i.e. eax - the other arguments shift up and the + function's register parameters degenerate to regparm=2 in essence. + +*/ + +#ifdef CONFIG_X86_64 + +/* + * 64-bit system call stack frame layout defines and helpers, + * for assembly code: + */ + +/* The layout forms the "struct pt_regs" on the stack: */ +/* + * C ABI says these regs are callee-preserved. They aren't saved on kernel entry + * unless syscall needs a complete, fully filled "struct pt_regs". + */ +#define R15 0*8 +#define R14 1*8 +#define R13 2*8 +#define R12 3*8 +#define RBP 4*8 +#define RBX 5*8 +/* These regs are callee-clobbered. Always saved on kernel entry. */ +#define R11 6*8 +#define R10 7*8 +#define R9 8*8 +#define R8 9*8 +#define RAX 10*8 +#define RCX 11*8 +#define RDX 12*8 +#define RSI 13*8 +#define RDI 14*8 +/* + * On syscall entry, this is syscall#. On CPU exception, this is error code. + * On hw interrupt, it's IRQ number: + */ +#define ORIG_RAX 15*8 +/* Return frame for iretq */ +#define RIP 16*8 +#define CS 17*8 +#define EFLAGS 18*8 +#define RSP 19*8 +#define SS 20*8 + +#define SIZEOF_PTREGS 21*8 + + .macro ALLOC_PT_GPREGS_ON_STACK addskip=0 + addq $-(15*8+\addskip), %rsp + .endm + + .macro SAVE_C_REGS_HELPER offset=0 rax=1 rcx=1 r8910=1 r11=1 + .if \r11 + movq %r11, 6*8+\offset(%rsp) + .endif + .if \r8910 + movq %r10, 7*8+\offset(%rsp) + movq %r9, 8*8+\offset(%rsp) + movq %r8, 9*8+\offset(%rsp) + .endif + .if \rax + movq %rax, 10*8+\offset(%rsp) + .endif + .if \rcx + movq %rcx, 11*8+\offset(%rsp) + .endif + movq %rdx, 12*8+\offset(%rsp) + movq %rsi, 13*8+\offset(%rsp) + movq %rdi, 14*8+\offset(%rsp) + .endm + .macro SAVE_C_REGS offset=0 + SAVE_C_REGS_HELPER \offset, 1, 1, 1, 1 + .endm + .macro SAVE_C_REGS_EXCEPT_RAX_RCX offset=0 + SAVE_C_REGS_HELPER \offset, 0, 0, 1, 1 + .endm + .macro SAVE_C_REGS_EXCEPT_R891011 + SAVE_C_REGS_HELPER 0, 1, 1, 0, 0 + .endm + .macro SAVE_C_REGS_EXCEPT_RCX_R891011 + SAVE_C_REGS_HELPER 0, 1, 0, 0, 0 + .endm + .macro SAVE_C_REGS_EXCEPT_RAX_RCX_R11 + SAVE_C_REGS_HELPER 0, 0, 0, 1, 0 + .endm + + .macro SAVE_EXTRA_REGS offset=0 + movq %r15, 0*8+\offset(%rsp) + movq %r14, 1*8+\offset(%rsp) + movq %r13, 2*8+\offset(%rsp) + movq %r12, 3*8+\offset(%rsp) + movq %rbp, 4*8+\offset(%rsp) + movq %rbx, 5*8+\offset(%rsp) + .endm + .macro SAVE_EXTRA_REGS_RBP offset=0 + movq %rbp, 4*8+\offset(%rsp) + .endm + + .macro RESTORE_EXTRA_REGS offset=0 + movq 0*8+\offset(%rsp), %r15 + movq 1*8+\offset(%rsp), %r14 + movq 2*8+\offset(%rsp), %r13 + movq 3*8+\offset(%rsp), %r12 + movq 4*8+\offset(%rsp), %rbp + movq 5*8+\offset(%rsp), %rbx + .endm + + .macro ZERO_EXTRA_REGS + xorl %r15d, %r15d + xorl %r14d, %r14d + xorl %r13d, %r13d + xorl %r12d, %r12d + xorl %ebp, %ebp + xorl %ebx, %ebx + .endm + + .macro RESTORE_C_REGS_HELPER rstor_rax=1, rstor_rcx=1, rstor_r11=1, rstor_r8910=1, rstor_rdx=1 + .if \rstor_r11 + movq 6*8(%rsp), %r11 + .endif + .if \rstor_r8910 + movq 7*8(%rsp), %r10 + movq 8*8(%rsp), %r9 + movq 9*8(%rsp), %r8 + .endif + .if \rstor_rax + movq 10*8(%rsp), %rax + .endif + .if \rstor_rcx + movq 11*8(%rsp), %rcx + .endif + .if \rstor_rdx + movq 12*8(%rsp), %rdx + .endif + movq 13*8(%rsp), %rsi + movq 14*8(%rsp), %rdi + .endm + .macro RESTORE_C_REGS + RESTORE_C_REGS_HELPER 1,1,1,1,1 + .endm + .macro RESTORE_C_REGS_EXCEPT_RAX + RESTORE_C_REGS_HELPER 0,1,1,1,1 + .endm + .macro RESTORE_C_REGS_EXCEPT_RCX + RESTORE_C_REGS_HELPER 1,0,1,1,1 + .endm + .macro RESTORE_C_REGS_EXCEPT_R11 + RESTORE_C_REGS_HELPER 1,1,0,1,1 + .endm + .macro RESTORE_C_REGS_EXCEPT_RCX_R11 + RESTORE_C_REGS_HELPER 1,0,0,1,1 + .endm + .macro RESTORE_RSI_RDI + RESTORE_C_REGS_HELPER 0,0,0,0,0 + .endm + .macro RESTORE_RSI_RDI_RDX + RESTORE_C_REGS_HELPER 0,0,0,0,1 + .endm + + .macro REMOVE_PT_GPREGS_FROM_STACK addskip=0 + subq $-(15*8+\addskip), %rsp + .endm + + .macro icebp + .byte 0xf1 + .endm + +#else /* CONFIG_X86_64 */ + +/* + * For 32bit only simplified versions of SAVE_ALL/RESTORE_ALL. These + * are different from the entry_32.S versions in not changing the segment + * registers. So only suitable for in kernel use, not when transitioning + * from or to user space. The resulting stack frame is not a standard + * pt_regs frame. The main use case is calling C code from assembler + * when all the registers need to be preserved. + */ + + .macro SAVE_ALL + pushl %eax + pushl %ebp + pushl %edi + pushl %esi + pushl %edx + pushl %ecx + pushl %ebx + .endm + + .macro RESTORE_ALL + popl %ebx + popl %ecx + popl %edx + popl %esi + popl %edi + popl %ebp + popl %eax + .endm + +#endif /* CONFIG_X86_64 */ + diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 4ad79e946f5a..f7380ea75777 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -28,7 +28,7 @@ #include #include #include -#include +#include "calling.h" #include #include #include diff --git a/arch/x86/entry/ia32entry.S b/arch/x86/entry/ia32entry.S index 2be23c734db5..f16767417385 100644 --- a/arch/x86/entry/ia32entry.S +++ b/arch/x86/entry/ia32entry.S @@ -4,7 +4,7 @@ * Copyright 2000-2002 Andi Kleen, SuSE Labs. */ -#include +#include "calling.h" #include #include #include diff --git a/arch/x86/entry/thunk_64.S b/arch/x86/entry/thunk_64.S index 10f555e435e1..3e95681b4e2d 100644 --- a/arch/x86/entry/thunk_64.S +++ b/arch/x86/entry/thunk_64.S @@ -6,7 +6,7 @@ * Subject to the GNU public license, v.2. No warranty of any kind. */ #include -#include +#include "calling.h" #include /* rdi: arg1 ... normal C conventions. rax is saved/restored. */ diff --git a/arch/x86/include/asm/calling.h b/arch/x86/include/asm/calling.h deleted file mode 100644 index f4e6308c4200..000000000000 --- a/arch/x86/include/asm/calling.h +++ /dev/null @@ -1,243 +0,0 @@ -/* - - x86 function call convention, 64-bit: - ------------------------------------- - arguments | callee-saved | extra caller-saved | return - [callee-clobbered] | | [callee-clobbered] | - --------------------------------------------------------------------------- - rdi rsi rdx rcx r8-9 | rbx rbp [*] r12-15 | r10-11 | rax, rdx [**] - - ( rsp is obviously invariant across normal function calls. (gcc can 'merge' - functions when it sees tail-call optimization possibilities) rflags is - clobbered. Leftover arguments are passed over the stack frame.) - - [*] In the frame-pointers case rbp is fixed to the stack frame. - - [**] for struct return values wider than 64 bits the return convention is a - bit more complex: up to 128 bits width we return small structures - straight in rax, rdx. For structures larger than that (3 words or - larger) the caller puts a pointer to an on-stack return struct - [allocated in the caller's stack frame] into the first argument - i.e. - into rdi. All other arguments shift up by one in this case. - Fortunately this case is rare in the kernel. - -For 32-bit we have the following conventions - kernel is built with --mregparm=3 and -freg-struct-return: - - x86 function calling convention, 32-bit: - ---------------------------------------- - arguments | callee-saved | extra caller-saved | return - [callee-clobbered] | | [callee-clobbered] | - ------------------------------------------------------------------------- - eax edx ecx | ebx edi esi ebp [*] | | eax, edx [**] - - ( here too esp is obviously invariant across normal function calls. eflags - is clobbered. Leftover arguments are passed over the stack frame. ) - - [*] In the frame-pointers case ebp is fixed to the stack frame. - - [**] We build with -freg-struct-return, which on 32-bit means similar - semantics as on 64-bit: edx can be used for a second return value - (i.e. covering integer and structure sizes up to 64 bits) - after that - it gets more complex and more expensive: 3-word or larger struct returns - get done in the caller's frame and the pointer to the return struct goes - into regparm0, i.e. eax - the other arguments shift up and the - function's register parameters degenerate to regparm=2 in essence. - -*/ - -#ifdef CONFIG_X86_64 - -/* - * 64-bit system call stack frame layout defines and helpers, - * for assembly code: - */ - -/* The layout forms the "struct pt_regs" on the stack: */ -/* - * C ABI says these regs are callee-preserved. They aren't saved on kernel entry - * unless syscall needs a complete, fully filled "struct pt_regs". - */ -#define R15 0*8 -#define R14 1*8 -#define R13 2*8 -#define R12 3*8 -#define RBP 4*8 -#define RBX 5*8 -/* These regs are callee-clobbered. Always saved on kernel entry. */ -#define R11 6*8 -#define R10 7*8 -#define R9 8*8 -#define R8 9*8 -#define RAX 10*8 -#define RCX 11*8 -#define RDX 12*8 -#define RSI 13*8 -#define RDI 14*8 -/* - * On syscall entry, this is syscall#. On CPU exception, this is error code. - * On hw interrupt, it's IRQ number: - */ -#define ORIG_RAX 15*8 -/* Return frame for iretq */ -#define RIP 16*8 -#define CS 17*8 -#define EFLAGS 18*8 -#define RSP 19*8 -#define SS 20*8 - -#define SIZEOF_PTREGS 21*8 - - .macro ALLOC_PT_GPREGS_ON_STACK addskip=0 - addq $-(15*8+\addskip), %rsp - .endm - - .macro SAVE_C_REGS_HELPER offset=0 rax=1 rcx=1 r8910=1 r11=1 - .if \r11 - movq %r11, 6*8+\offset(%rsp) - .endif - .if \r8910 - movq %r10, 7*8+\offset(%rsp) - movq %r9, 8*8+\offset(%rsp) - movq %r8, 9*8+\offset(%rsp) - .endif - .if \rax - movq %rax, 10*8+\offset(%rsp) - .endif - .if \rcx - movq %rcx, 11*8+\offset(%rsp) - .endif - movq %rdx, 12*8+\offset(%rsp) - movq %rsi, 13*8+\offset(%rsp) - movq %rdi, 14*8+\offset(%rsp) - .endm - .macro SAVE_C_REGS offset=0 - SAVE_C_REGS_HELPER \offset, 1, 1, 1, 1 - .endm - .macro SAVE_C_REGS_EXCEPT_RAX_RCX offset=0 - SAVE_C_REGS_HELPER \offset, 0, 0, 1, 1 - .endm - .macro SAVE_C_REGS_EXCEPT_R891011 - SAVE_C_REGS_HELPER 0, 1, 1, 0, 0 - .endm - .macro SAVE_C_REGS_EXCEPT_RCX_R891011 - SAVE_C_REGS_HELPER 0, 1, 0, 0, 0 - .endm - .macro SAVE_C_REGS_EXCEPT_RAX_RCX_R11 - SAVE_C_REGS_HELPER 0, 0, 0, 1, 0 - .endm - - .macro SAVE_EXTRA_REGS offset=0 - movq %r15, 0*8+\offset(%rsp) - movq %r14, 1*8+\offset(%rsp) - movq %r13, 2*8+\offset(%rsp) - movq %r12, 3*8+\offset(%rsp) - movq %rbp, 4*8+\offset(%rsp) - movq %rbx, 5*8+\offset(%rsp) - .endm - .macro SAVE_EXTRA_REGS_RBP offset=0 - movq %rbp, 4*8+\offset(%rsp) - .endm - - .macro RESTORE_EXTRA_REGS offset=0 - movq 0*8+\offset(%rsp), %r15 - movq 1*8+\offset(%rsp), %r14 - movq 2*8+\offset(%rsp), %r13 - movq 3*8+\offset(%rsp), %r12 - movq 4*8+\offset(%rsp), %rbp - movq 5*8+\offset(%rsp), %rbx - .endm - - .macro ZERO_EXTRA_REGS - xorl %r15d, %r15d - xorl %r14d, %r14d - xorl %r13d, %r13d - xorl %r12d, %r12d - xorl %ebp, %ebp - xorl %ebx, %ebx - .endm - - .macro RESTORE_C_REGS_HELPER rstor_rax=1, rstor_rcx=1, rstor_r11=1, rstor_r8910=1, rstor_rdx=1 - .if \rstor_r11 - movq 6*8(%rsp), %r11 - .endif - .if \rstor_r8910 - movq 7*8(%rsp), %r10 - movq 8*8(%rsp), %r9 - movq 9*8(%rsp), %r8 - .endif - .if \rstor_rax - movq 10*8(%rsp), %rax - .endif - .if \rstor_rcx - movq 11*8(%rsp), %rcx - .endif - .if \rstor_rdx - movq 12*8(%rsp), %rdx - .endif - movq 13*8(%rsp), %rsi - movq 14*8(%rsp), %rdi - .endm - .macro RESTORE_C_REGS - RESTORE_C_REGS_HELPER 1,1,1,1,1 - .endm - .macro RESTORE_C_REGS_EXCEPT_RAX - RESTORE_C_REGS_HELPER 0,1,1,1,1 - .endm - .macro RESTORE_C_REGS_EXCEPT_RCX - RESTORE_C_REGS_HELPER 1,0,1,1,1 - .endm - .macro RESTORE_C_REGS_EXCEPT_R11 - RESTORE_C_REGS_HELPER 1,1,0,1,1 - .endm - .macro RESTORE_C_REGS_EXCEPT_RCX_R11 - RESTORE_C_REGS_HELPER 1,0,0,1,1 - .endm - .macro RESTORE_RSI_RDI - RESTORE_C_REGS_HELPER 0,0,0,0,0 - .endm - .macro RESTORE_RSI_RDI_RDX - RESTORE_C_REGS_HELPER 0,0,0,0,1 - .endm - - .macro REMOVE_PT_GPREGS_FROM_STACK addskip=0 - subq $-(15*8+\addskip), %rsp - .endm - - .macro icebp - .byte 0xf1 - .endm - -#else /* CONFIG_X86_64 */ - -/* - * For 32bit only simplified versions of SAVE_ALL/RESTORE_ALL. These - * are different from the entry_32.S versions in not changing the segment - * registers. So only suitable for in kernel use, not when transitioning - * from or to user space. The resulting stack frame is not a standard - * pt_regs frame. The main use case is calling C code from assembler - * when all the registers need to be preserved. - */ - - .macro SAVE_ALL - pushl %eax - pushl %ebp - pushl %edi - pushl %esi - pushl %edx - pushl %ecx - pushl %ebx - .endm - - .macro RESTORE_ALL - popl %ebx - popl %ecx - popl %edx - popl %esi - popl %edi - popl %ebp - popl %eax - .endm - -#endif /* CONFIG_X86_64 */ -