linux_dsm_epyc7002/arch/x86/include/asm/asm.h
Peter Zijlstra 3693ca8115 x86/uaccess: Move copy_user_handle_tail() into asm
By writing the function in asm we avoid cross object code flow and
objtool no longer gets confused about a 'stray' CLAC.

Also; the asm version is actually _simpler_.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-03 09:36:29 +02:00

191 lines
4.7 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_ASM_H
#define _ASM_X86_ASM_H
#ifdef __ASSEMBLY__
# define __ASM_FORM(x) x
# define __ASM_FORM_RAW(x) x
# define __ASM_FORM_COMMA(x) x,
#else
# define __ASM_FORM(x) " " #x " "
# define __ASM_FORM_RAW(x) #x
# define __ASM_FORM_COMMA(x) " " #x ","
#endif
#ifndef __x86_64__
/* 32 bit */
# define __ASM_SEL(a,b) __ASM_FORM(a)
# define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(a)
#else
/* 64 bit */
# define __ASM_SEL(a,b) __ASM_FORM(b)
# define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(b)
#endif
#define __ASM_SIZE(inst, ...) __ASM_SEL(inst##l##__VA_ARGS__, \
inst##q##__VA_ARGS__)
#define __ASM_REG(reg) __ASM_SEL_RAW(e##reg, r##reg)
#define _ASM_PTR __ASM_SEL(.long, .quad)
#define _ASM_ALIGN __ASM_SEL(.balign 4, .balign 8)
#define _ASM_MOV __ASM_SIZE(mov)
#define _ASM_INC __ASM_SIZE(inc)
#define _ASM_DEC __ASM_SIZE(dec)
#define _ASM_ADD __ASM_SIZE(add)
#define _ASM_SUB __ASM_SIZE(sub)
#define _ASM_XADD __ASM_SIZE(xadd)
#define _ASM_MUL __ASM_SIZE(mul)
#define _ASM_AX __ASM_REG(ax)
#define _ASM_BX __ASM_REG(bx)
#define _ASM_CX __ASM_REG(cx)
#define _ASM_DX __ASM_REG(dx)
#define _ASM_SP __ASM_REG(sp)
#define _ASM_BP __ASM_REG(bp)
#define _ASM_SI __ASM_REG(si)
#define _ASM_DI __ASM_REG(di)
#ifndef __x86_64__
/* 32 bit */
#define _ASM_ARG1 _ASM_AX
#define _ASM_ARG2 _ASM_DX
#define _ASM_ARG3 _ASM_CX
#define _ASM_ARG1L eax
#define _ASM_ARG2L edx
#define _ASM_ARG3L ecx
#define _ASM_ARG1W ax
#define _ASM_ARG2W dx
#define _ASM_ARG3W cx
#define _ASM_ARG1B al
#define _ASM_ARG2B dl
#define _ASM_ARG3B cl
#else
/* 64 bit */
#define _ASM_ARG1 _ASM_DI
#define _ASM_ARG2 _ASM_SI
#define _ASM_ARG3 _ASM_DX
#define _ASM_ARG4 _ASM_CX
#define _ASM_ARG5 r8
#define _ASM_ARG6 r9
#define _ASM_ARG1Q rdi
#define _ASM_ARG2Q rsi
#define _ASM_ARG3Q rdx
#define _ASM_ARG4Q rcx
#define _ASM_ARG5Q r8
#define _ASM_ARG6Q r9
#define _ASM_ARG1L edi
#define _ASM_ARG2L esi
#define _ASM_ARG3L edx
#define _ASM_ARG4L ecx
#define _ASM_ARG5L r8d
#define _ASM_ARG6L r9d
#define _ASM_ARG1W di
#define _ASM_ARG2W si
#define _ASM_ARG3W dx
#define _ASM_ARG4W cx
#define _ASM_ARG5W r8w
#define _ASM_ARG6W r9w
#define _ASM_ARG1B dil
#define _ASM_ARG2B sil
#define _ASM_ARG3B dl
#define _ASM_ARG4B cl
#define _ASM_ARG5B r8b
#define _ASM_ARG6B r9b
#endif
/*
* Macros to generate condition code outputs from inline assembly,
* The output operand must be type "bool".
*/
#ifdef __GCC_ASM_FLAG_OUTPUTS__
# define CC_SET(c) "\n\t/* output condition code " #c "*/\n"
# define CC_OUT(c) "=@cc" #c
#else
# define CC_SET(c) "\n\tset" #c " %[_cc_" #c "]\n"
# define CC_OUT(c) [_cc_ ## c] "=qm"
#endif
/* Exception table entry */
#ifdef __ASSEMBLY__
# define _ASM_EXTABLE_HANDLE(from, to, handler) \
.pushsection "__ex_table","a" ; \
.balign 4 ; \
.long (from) - . ; \
.long (to) - . ; \
.long (handler) - . ; \
.popsection
# define _ASM_EXTABLE(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_default)
# define _ASM_EXTABLE_UA(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_uaccess)
# define _ASM_EXTABLE_FAULT(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_fault)
# define _ASM_EXTABLE_EX(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_ext)
# define _ASM_EXTABLE_REFCOUNT(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_refcount)
# define _ASM_NOKPROBE(entry) \
.pushsection "_kprobe_blacklist","aw" ; \
_ASM_ALIGN ; \
_ASM_PTR (entry); \
.popsection
#else
# define _EXPAND_EXTABLE_HANDLE(x) #x
# define _ASM_EXTABLE_HANDLE(from, to, handler) \
" .pushsection \"__ex_table\",\"a\"\n" \
" .balign 4\n" \
" .long (" #from ") - .\n" \
" .long (" #to ") - .\n" \
" .long (" _EXPAND_EXTABLE_HANDLE(handler) ") - .\n" \
" .popsection\n"
# define _ASM_EXTABLE(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_default)
# define _ASM_EXTABLE_UA(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_uaccess)
# define _ASM_EXTABLE_FAULT(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_fault)
# define _ASM_EXTABLE_EX(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_ext)
# define _ASM_EXTABLE_REFCOUNT(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_refcount)
/* For C file, we already have NOKPROBE_SYMBOL macro */
#endif
#ifndef __ASSEMBLY__
/*
* This output constraint should be used for any inline asm which has a "call"
* instruction. Otherwise the asm may be inserted before the frame pointer
* gets set up by the containing function. If you forget to do this, objtool
* may print a "call without frame pointer save/setup" warning.
*/
register unsigned long current_stack_pointer asm(_ASM_SP);
#define ASM_CALL_CONSTRAINT "+r" (current_stack_pointer)
#endif
#endif /* _ASM_X86_ASM_H */