/* copy_in_user.S: Copy from userspace to userspace. | |
* | |
* Copyright (C) 1999, 2000, 2004 David S. Miller (davem@redhat.com) | |
*/ | |
#include <linux/linkage.h> | |
#include <asm/asi.h> | |
#define XCC xcc | |
#define EX(x,y) \ | |
98: x,y; \ | |
.section __ex_table,"a";\ | |
.align 4; \ | |
.word 98b, __retl_one; \ | |
.text; \ | |
.align 4; | |
.register %g2,#scratch | |
.register %g3,#scratch | |
.text | |
.align 32 | |
/* Don't try to get too fancy here, just nice and | |
* simple. This is predominantly used for well aligned | |
* small copies in the compat layer. It is also used | |
* to copy register windows around during thread cloning. | |
*/ | |
ENTRY(___copy_in_user) /* %o0=dst, %o1=src, %o2=len */ | |
cmp %o2, 0 | |
be,pn %XCC, 85f | |
or %o0, %o1, %o3 | |
cmp %o2, 16 | |
bleu,a,pn %XCC, 80f | |
or %o3, %o2, %o3 | |
/* 16 < len <= 64 */ | |
andcc %o3, 0x7, %g0 | |
bne,pn %XCC, 90f | |
nop | |
andn %o2, 0x7, %o4 | |
and %o2, 0x7, %o2 | |
1: subcc %o4, 0x8, %o4 | |
EX(ldxa [%o1] %asi, %o5) | |
EX(stxa %o5, [%o0] %asi) | |
add %o1, 0x8, %o1 | |
bgu,pt %XCC, 1b | |
add %o0, 0x8, %o0 | |
andcc %o2, 0x4, %g0 | |
be,pt %XCC, 1f | |
nop | |
sub %o2, 0x4, %o2 | |
EX(lduwa [%o1] %asi, %o5) | |
EX(stwa %o5, [%o0] %asi) | |
add %o1, 0x4, %o1 | |
add %o0, 0x4, %o0 | |
1: cmp %o2, 0 | |
be,pt %XCC, 85f | |
nop | |
ba,pt %xcc, 90f | |
nop | |
80: /* 0 < len <= 16 */ | |
andcc %o3, 0x3, %g0 | |
bne,pn %XCC, 90f | |
nop | |
82: | |
subcc %o2, 4, %o2 | |
EX(lduwa [%o1] %asi, %g1) | |
EX(stwa %g1, [%o0] %asi) | |
add %o1, 4, %o1 | |
bgu,pt %XCC, 82b | |
add %o0, 4, %o0 | |
85: retl | |
clr %o0 | |
.align 32 | |
90: | |
subcc %o2, 1, %o2 | |
EX(lduba [%o1] %asi, %g1) | |
EX(stba %g1, [%o0] %asi) | |
add %o1, 1, %o1 | |
bgu,pt %XCC, 90b | |
add %o0, 1, %o0 | |
retl | |
clr %o0 | |
ENDPROC(___copy_in_user) |