mirror of
https://github.com/torvalds/linux.git
synced 2024-11-25 21:51:40 +00:00
94ea9c0521
The following commit:
ddb5cdbafa ("kbuild: generate KSYMTAB entries by modpost")
deprecated <asm/export.h>, which is now a wrapper of <linux/export.h>.
Use <linux/export.h> in *.S as well as in *.c files.
After all the <asm/export.h> lines are replaced, <asm/export.h> and
<asm-generic/export.h> will be removed.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230806145958.380314-2-masahiroy@kernel.org
142 lines
2.8 KiB
ArmAsm
142 lines
2.8 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
#include <linux/export.h>
|
|
#include <linux/linkage.h>
|
|
#include <asm/asm.h>
|
|
|
|
/*
|
|
* Most CPUs support enhanced REP MOVSB/STOSB instructions. It is
|
|
* recommended to use this when possible and we do use them by default.
|
|
* If enhanced REP MOVSB/STOSB is not available, try to use fast string.
|
|
* Otherwise, use original.
|
|
*/
|
|
|
|
/*
|
|
* Zero a page.
|
|
* %rdi - page
|
|
*/
|
|
SYM_FUNC_START(clear_page_rep)
|
|
movl $4096/8,%ecx
|
|
xorl %eax,%eax
|
|
rep stosq
|
|
RET
|
|
SYM_FUNC_END(clear_page_rep)
|
|
EXPORT_SYMBOL_GPL(clear_page_rep)
|
|
|
|
SYM_FUNC_START(clear_page_orig)
|
|
xorl %eax,%eax
|
|
movl $4096/64,%ecx
|
|
.p2align 4
|
|
.Lloop:
|
|
decl %ecx
|
|
#define PUT(x) movq %rax,x*8(%rdi)
|
|
movq %rax,(%rdi)
|
|
PUT(1)
|
|
PUT(2)
|
|
PUT(3)
|
|
PUT(4)
|
|
PUT(5)
|
|
PUT(6)
|
|
PUT(7)
|
|
leaq 64(%rdi),%rdi
|
|
jnz .Lloop
|
|
nop
|
|
RET
|
|
SYM_FUNC_END(clear_page_orig)
|
|
EXPORT_SYMBOL_GPL(clear_page_orig)
|
|
|
|
SYM_FUNC_START(clear_page_erms)
|
|
movl $4096,%ecx
|
|
xorl %eax,%eax
|
|
rep stosb
|
|
RET
|
|
SYM_FUNC_END(clear_page_erms)
|
|
EXPORT_SYMBOL_GPL(clear_page_erms)
|
|
|
|
/*
|
|
* Default clear user-space.
|
|
* Input:
|
|
* rdi destination
|
|
* rcx count
|
|
* rax is zero
|
|
*
|
|
* Output:
|
|
* rcx: uncleared bytes or 0 if successful.
|
|
*/
|
|
SYM_FUNC_START(rep_stos_alternative)
|
|
cmpq $64,%rcx
|
|
jae .Lunrolled
|
|
|
|
cmp $8,%ecx
|
|
jae .Lword
|
|
|
|
testl %ecx,%ecx
|
|
je .Lexit
|
|
|
|
.Lclear_user_tail:
|
|
0: movb %al,(%rdi)
|
|
inc %rdi
|
|
dec %rcx
|
|
jnz .Lclear_user_tail
|
|
.Lexit:
|
|
RET
|
|
|
|
_ASM_EXTABLE_UA( 0b, .Lexit)
|
|
|
|
.Lword:
|
|
1: movq %rax,(%rdi)
|
|
addq $8,%rdi
|
|
sub $8,%ecx
|
|
je .Lexit
|
|
cmp $8,%ecx
|
|
jae .Lword
|
|
jmp .Lclear_user_tail
|
|
|
|
.p2align 4
|
|
.Lunrolled:
|
|
10: movq %rax,(%rdi)
|
|
11: movq %rax,8(%rdi)
|
|
12: movq %rax,16(%rdi)
|
|
13: movq %rax,24(%rdi)
|
|
14: movq %rax,32(%rdi)
|
|
15: movq %rax,40(%rdi)
|
|
16: movq %rax,48(%rdi)
|
|
17: movq %rax,56(%rdi)
|
|
addq $64,%rdi
|
|
subq $64,%rcx
|
|
cmpq $64,%rcx
|
|
jae .Lunrolled
|
|
cmpl $8,%ecx
|
|
jae .Lword
|
|
testl %ecx,%ecx
|
|
jne .Lclear_user_tail
|
|
RET
|
|
|
|
/*
|
|
* If we take an exception on any of the
|
|
* word stores, we know that %rcx isn't zero,
|
|
* so we can just go to the tail clearing to
|
|
* get the exact count.
|
|
*
|
|
* The unrolled case might end up clearing
|
|
* some bytes twice. Don't care.
|
|
*
|
|
* We could use the value in %rdi to avoid
|
|
* a second fault on the exact count case,
|
|
* but do we really care? No.
|
|
*
|
|
* Finally, we could try to align %rdi at the
|
|
* top of the unrolling. But unaligned stores
|
|
* just aren't that common or expensive.
|
|
*/
|
|
_ASM_EXTABLE_UA( 1b, .Lclear_user_tail)
|
|
_ASM_EXTABLE_UA(10b, .Lclear_user_tail)
|
|
_ASM_EXTABLE_UA(11b, .Lclear_user_tail)
|
|
_ASM_EXTABLE_UA(12b, .Lclear_user_tail)
|
|
_ASM_EXTABLE_UA(13b, .Lclear_user_tail)
|
|
_ASM_EXTABLE_UA(14b, .Lclear_user_tail)
|
|
_ASM_EXTABLE_UA(15b, .Lclear_user_tail)
|
|
_ASM_EXTABLE_UA(16b, .Lclear_user_tail)
|
|
_ASM_EXTABLE_UA(17b, .Lclear_user_tail)
|
|
SYM_FUNC_END(rep_stos_alternative)
|
|
EXPORT_SYMBOL(rep_stos_alternative)
|