mirror of
https://github.com/FEX-Emu/linux.git
synced 2024-12-21 00:42:16 +00:00
df1bdc0667
movnt* instructions are not strongly ordered with respect to other stores, so if we are to assume stores are strongly ordered in the rest of the 64 bit code, we must fence these off (see similar examples in 32 bit code). [ The AMD memory ordering document seems to say that nontemporal stores can also pass earlier regular stores, so maybe we need sfences _before_ movnt* everywhere too? ] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
219 lines
4.1 KiB
ArmAsm
219 lines
4.1 KiB
ArmAsm
/* Copyright 2002 Andi Kleen, SuSE Labs.
|
|
* Subject to the GNU Public License v2.
|
|
*
|
|
* Functions to copy from and to user space.
|
|
*/
|
|
|
|
#include <linux/linkage.h>
|
|
#include <asm/dwarf2.h>
|
|
|
|
#define FIX_ALIGNMENT 1
|
|
|
|
#include <asm/current.h>
|
|
#include <asm/asm-offsets.h>
|
|
#include <asm/thread_info.h>
|
|
#include <asm/cpufeature.h>
|
|
|
|
/*
|
|
* copy_user_nocache - Uncached memory copy with exception handling
|
|
* This will force destination/source out of cache for more performance.
|
|
*
|
|
* Input:
|
|
* rdi destination
|
|
* rsi source
|
|
* rdx count
|
|
* rcx zero flag when 1 zero on exception
|
|
*
|
|
* Output:
|
|
* eax uncopied bytes or 0 if successful.
|
|
*/
|
|
ENTRY(__copy_user_nocache)
|
|
CFI_STARTPROC
|
|
pushq %rbx
|
|
CFI_ADJUST_CFA_OFFSET 8
|
|
CFI_REL_OFFSET rbx, 0
|
|
pushq %rcx /* save zero flag */
|
|
CFI_ADJUST_CFA_OFFSET 8
|
|
CFI_REL_OFFSET rcx, 0
|
|
|
|
xorl %eax,%eax /* zero for the exception handler */
|
|
|
|
#ifdef FIX_ALIGNMENT
|
|
/* check for bad alignment of destination */
|
|
movl %edi,%ecx
|
|
andl $7,%ecx
|
|
jnz .Lbad_alignment
|
|
.Lafter_bad_alignment:
|
|
#endif
|
|
|
|
movq %rdx,%rcx
|
|
|
|
movl $64,%ebx
|
|
shrq $6,%rdx
|
|
decq %rdx
|
|
js .Lhandle_tail
|
|
|
|
.p2align 4
|
|
.Lloop:
|
|
.Ls1: movq (%rsi),%r11
|
|
.Ls2: movq 1*8(%rsi),%r8
|
|
.Ls3: movq 2*8(%rsi),%r9
|
|
.Ls4: movq 3*8(%rsi),%r10
|
|
.Ld1: movnti %r11,(%rdi)
|
|
.Ld2: movnti %r8,1*8(%rdi)
|
|
.Ld3: movnti %r9,2*8(%rdi)
|
|
.Ld4: movnti %r10,3*8(%rdi)
|
|
|
|
.Ls5: movq 4*8(%rsi),%r11
|
|
.Ls6: movq 5*8(%rsi),%r8
|
|
.Ls7: movq 6*8(%rsi),%r9
|
|
.Ls8: movq 7*8(%rsi),%r10
|
|
.Ld5: movnti %r11,4*8(%rdi)
|
|
.Ld6: movnti %r8,5*8(%rdi)
|
|
.Ld7: movnti %r9,6*8(%rdi)
|
|
.Ld8: movnti %r10,7*8(%rdi)
|
|
|
|
dec %rdx
|
|
|
|
leaq 64(%rsi),%rsi
|
|
leaq 64(%rdi),%rdi
|
|
|
|
jns .Lloop
|
|
|
|
.p2align 4
|
|
.Lhandle_tail:
|
|
movl %ecx,%edx
|
|
andl $63,%ecx
|
|
shrl $3,%ecx
|
|
jz .Lhandle_7
|
|
movl $8,%ebx
|
|
.p2align 4
|
|
.Lloop_8:
|
|
.Ls9: movq (%rsi),%r8
|
|
.Ld9: movnti %r8,(%rdi)
|
|
decl %ecx
|
|
leaq 8(%rdi),%rdi
|
|
leaq 8(%rsi),%rsi
|
|
jnz .Lloop_8
|
|
|
|
.Lhandle_7:
|
|
movl %edx,%ecx
|
|
andl $7,%ecx
|
|
jz .Lende
|
|
.p2align 4
|
|
.Lloop_1:
|
|
.Ls10: movb (%rsi),%bl
|
|
.Ld10: movb %bl,(%rdi)
|
|
incq %rdi
|
|
incq %rsi
|
|
decl %ecx
|
|
jnz .Lloop_1
|
|
|
|
CFI_REMEMBER_STATE
|
|
.Lende:
|
|
popq %rcx
|
|
CFI_ADJUST_CFA_OFFSET -8
|
|
CFI_RESTORE %rcx
|
|
popq %rbx
|
|
CFI_ADJUST_CFA_OFFSET -8
|
|
CFI_RESTORE rbx
|
|
sfence
|
|
ret
|
|
CFI_RESTORE_STATE
|
|
|
|
#ifdef FIX_ALIGNMENT
|
|
/* align destination */
|
|
.p2align 4
|
|
.Lbad_alignment:
|
|
movl $8,%r9d
|
|
subl %ecx,%r9d
|
|
movl %r9d,%ecx
|
|
cmpq %r9,%rdx
|
|
jz .Lhandle_7
|
|
js .Lhandle_7
|
|
.Lalign_1:
|
|
.Ls11: movb (%rsi),%bl
|
|
.Ld11: movb %bl,(%rdi)
|
|
incq %rsi
|
|
incq %rdi
|
|
decl %ecx
|
|
jnz .Lalign_1
|
|
subq %r9,%rdx
|
|
jmp .Lafter_bad_alignment
|
|
#endif
|
|
|
|
/* table sorted by exception address */
|
|
.section __ex_table,"a"
|
|
.align 8
|
|
.quad .Ls1,.Ls1e
|
|
.quad .Ls2,.Ls2e
|
|
.quad .Ls3,.Ls3e
|
|
.quad .Ls4,.Ls4e
|
|
.quad .Ld1,.Ls1e
|
|
.quad .Ld2,.Ls2e
|
|
.quad .Ld3,.Ls3e
|
|
.quad .Ld4,.Ls4e
|
|
.quad .Ls5,.Ls5e
|
|
.quad .Ls6,.Ls6e
|
|
.quad .Ls7,.Ls7e
|
|
.quad .Ls8,.Ls8e
|
|
.quad .Ld5,.Ls5e
|
|
.quad .Ld6,.Ls6e
|
|
.quad .Ld7,.Ls7e
|
|
.quad .Ld8,.Ls8e
|
|
.quad .Ls9,.Le_quad
|
|
.quad .Ld9,.Le_quad
|
|
.quad .Ls10,.Le_byte
|
|
.quad .Ld10,.Le_byte
|
|
#ifdef FIX_ALIGNMENT
|
|
.quad .Ls11,.Lzero_rest
|
|
.quad .Ld11,.Lzero_rest
|
|
#endif
|
|
.quad .Le5,.Le_zero
|
|
.previous
|
|
|
|
/* compute 64-offset for main loop. 8 bytes accuracy with error on the
|
|
pessimistic side. this is gross. it would be better to fix the
|
|
interface. */
|
|
/* eax: zero, ebx: 64 */
|
|
.Ls1e: addl $8,%eax
|
|
.Ls2e: addl $8,%eax
|
|
.Ls3e: addl $8,%eax
|
|
.Ls4e: addl $8,%eax
|
|
.Ls5e: addl $8,%eax
|
|
.Ls6e: addl $8,%eax
|
|
.Ls7e: addl $8,%eax
|
|
.Ls8e: addl $8,%eax
|
|
addq %rbx,%rdi /* +64 */
|
|
subq %rax,%rdi /* correct destination with computed offset */
|
|
|
|
shlq $6,%rdx /* loop counter * 64 (stride length) */
|
|
addq %rax,%rdx /* add offset to loopcnt */
|
|
andl $63,%ecx /* remaining bytes */
|
|
addq %rcx,%rdx /* add them */
|
|
jmp .Lzero_rest
|
|
|
|
/* exception on quad word loop in tail handling */
|
|
/* ecx: loopcnt/8, %edx: length, rdi: correct */
|
|
.Le_quad:
|
|
shll $3,%ecx
|
|
andl $7,%edx
|
|
addl %ecx,%edx
|
|
/* edx: bytes to zero, rdi: dest, eax:zero */
|
|
.Lzero_rest:
|
|
cmpl $0,(%rsp) /* zero flag set? */
|
|
jz .Le_zero
|
|
movq %rdx,%rcx
|
|
.Le_byte:
|
|
xorl %eax,%eax
|
|
.Le5: rep
|
|
stosb
|
|
/* when there is another exception while zeroing the rest just return */
|
|
.Le_zero:
|
|
movq %rdx,%rax
|
|
jmp .Lende
|
|
CFI_ENDPROC
|
|
ENDPROC(__copy_user_nocache)
|
|
|
|
|