linux/arch/powerpc/lib/copyuser_64.S
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

565 lines
11 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Copyright (C) 2002 Paul Mackerras, IBM Corp.
*/
#include <asm/processor.h>
#include <asm/ppc_asm.h>
#include <asm/export.h>
#include <asm/asm-compat.h>
#include <asm/feature-fixups.h>
#ifndef SELFTEST_CASE
/* 0 == most CPUs, 1 == POWER6, 2 == Cell */
#define SELFTEST_CASE 0
#endif
#ifdef __BIG_ENDIAN__
#define sLd sld /* Shift towards low-numbered address. */
#define sHd srd /* Shift towards high-numbered address. */
#else
#define sLd srd /* Shift towards low-numbered address. */
#define sHd sld /* Shift towards high-numbered address. */
#endif
/*
* These macros are used to generate exception table entries.
* The exception handlers below use the original arguments
* (stored on the stack) and the point where we're up to in
* the destination buffer, i.e. the address of the first
* unmodified byte. Generally r3 points into the destination
* buffer, but the first unmodified byte is at a variable
* offset from r3. In the code below, the symbol r3_offset
* is set to indicate the current offset at each point in
* the code. This offset is then used as a negative offset
* from the exception handler code, and those instructions
* before the exception handlers are addi instructions that
* adjust r3 to point to the correct place.
*/
.macro lex /* exception handler for load */
100: EX_TABLE(100b, .Lld_exc - r3_offset)
.endm
.macro stex /* exception handler for store */
100: EX_TABLE(100b, .Lst_exc - r3_offset)
.endm
.align 7
_GLOBAL_TOC(__copy_tofrom_user)
#ifdef CONFIG_PPC_BOOK3S_64
BEGIN_FTR_SECTION
nop
FTR_SECTION_ELSE
b __copy_tofrom_user_power7
ALT_FTR_SECTION_END_IFCLR(CPU_FTR_VMX_COPY)
#endif
_GLOBAL(__copy_tofrom_user_base)
/* first check for a 4kB copy on a 4kB boundary */
cmpldi cr1,r5,16
cmpdi cr6,r5,4096
or r0,r3,r4
neg r6,r3 /* LS 3 bits = # bytes to 8-byte dest bdry */
andi. r0,r0,4095
std r3,-24(r1)
crand cr0*4+2,cr0*4+2,cr6*4+2
std r4,-16(r1)
std r5,-8(r1)
dcbt 0,r4
beq .Lcopy_page_4K
andi. r6,r6,7
PPC_MTOCRF(0x01,r5)
blt cr1,.Lshort_copy
/* Below we want to nop out the bne if we're on a CPU that has the
* CPU_FTR_UNALIGNED_LD_STD bit set and the CPU_FTR_CP_USE_DCBTZ bit
* cleared.
* At the time of writing the only CPU that has this combination of bits
* set is Power6.
*/
test_feature = (SELFTEST_CASE == 1)
BEGIN_FTR_SECTION
nop
FTR_SECTION_ELSE
bne .Ldst_unaligned
ALT_FTR_SECTION_END(CPU_FTR_UNALIGNED_LD_STD | CPU_FTR_CP_USE_DCBTZ, \
CPU_FTR_UNALIGNED_LD_STD)
.Ldst_aligned:
addi r3,r3,-16
r3_offset = 16
test_feature = (SELFTEST_CASE == 0)
BEGIN_FTR_SECTION
andi. r0,r4,7
bne .Lsrc_unaligned
END_FTR_SECTION_IFCLR(CPU_FTR_UNALIGNED_LD_STD)
blt cr1,.Ldo_tail /* if < 16 bytes to copy */
srdi r0,r5,5
cmpdi cr1,r0,0
lex; ld r7,0(r4)
lex; ld r6,8(r4)
addi r4,r4,16
mtctr r0
andi. r0,r5,0x10
beq 22f
addi r3,r3,16
r3_offset = 0
addi r4,r4,-16
mr r9,r7
mr r8,r6
beq cr1,72f
21:
lex; ld r7,16(r4)
lex; ld r6,24(r4)
addi r4,r4,32
stex; std r9,0(r3)
r3_offset = 8
stex; std r8,8(r3)
r3_offset = 16
22:
lex; ld r9,0(r4)
lex; ld r8,8(r4)
stex; std r7,16(r3)
r3_offset = 24
stex; std r6,24(r3)
addi r3,r3,32
r3_offset = 0
bdnz 21b
72:
stex; std r9,0(r3)
r3_offset = 8
stex; std r8,8(r3)
r3_offset = 16
andi. r5,r5,0xf
beq+ 3f
addi r4,r4,16
.Ldo_tail:
addi r3,r3,16
r3_offset = 0
bf cr7*4+0,246f
lex; ld r9,0(r4)
addi r4,r4,8
stex; std r9,0(r3)
addi r3,r3,8
246: bf cr7*4+1,1f
lex; lwz r9,0(r4)
addi r4,r4,4
stex; stw r9,0(r3)
addi r3,r3,4
1: bf cr7*4+2,2f
lex; lhz r9,0(r4)
addi r4,r4,2
stex; sth r9,0(r3)
addi r3,r3,2
2: bf cr7*4+3,3f
lex; lbz r9,0(r4)
stex; stb r9,0(r3)
3: li r3,0
blr
.Lsrc_unaligned:
r3_offset = 16
srdi r6,r5,3
addi r5,r5,-16
subf r4,r0,r4
srdi r7,r5,4
sldi r10,r0,3
cmpldi cr6,r6,3
andi. r5,r5,7
mtctr r7
subfic r11,r10,64
add r5,r5,r0
bt cr7*4+0,28f
lex; ld r9,0(r4) /* 3+2n loads, 2+2n stores */
lex; ld r0,8(r4)
sLd r6,r9,r10
lex; ldu r9,16(r4)
sHd r7,r0,r11
sLd r8,r0,r10
or r7,r7,r6
blt cr6,79f
lex; ld r0,8(r4)
b 2f
28:
lex; ld r0,0(r4) /* 4+2n loads, 3+2n stores */
lex; ldu r9,8(r4)
sLd r8,r0,r10
addi r3,r3,-8
r3_offset = 24
blt cr6,5f
lex; ld r0,8(r4)
sHd r12,r9,r11
sLd r6,r9,r10
lex; ldu r9,16(r4)
or r12,r8,r12
sHd r7,r0,r11
sLd r8,r0,r10
addi r3,r3,16
r3_offset = 8
beq cr6,78f
1: or r7,r7,r6
lex; ld r0,8(r4)
stex; std r12,8(r3)
r3_offset = 16
2: sHd r12,r9,r11
sLd r6,r9,r10
lex; ldu r9,16(r4)
or r12,r8,r12
stex; stdu r7,16(r3)
r3_offset = 8
sHd r7,r0,r11
sLd r8,r0,r10
bdnz 1b
78:
stex; std r12,8(r3)
r3_offset = 16
or r7,r7,r6
79:
stex; std r7,16(r3)
r3_offset = 24
5: sHd r12,r9,r11
or r12,r8,r12
stex; std r12,24(r3)
r3_offset = 32
bne 6f
li r3,0
blr
6: cmpwi cr1,r5,8
addi r3,r3,32
r3_offset = 0
sLd r9,r9,r10
ble cr1,7f
lex; ld r0,8(r4)
sHd r7,r0,r11
or r9,r7,r9
7:
bf cr7*4+1,1f
#ifdef __BIG_ENDIAN__
rotldi r9,r9,32
#endif
stex; stw r9,0(r3)
#ifdef __LITTLE_ENDIAN__
rotrdi r9,r9,32
#endif
addi r3,r3,4
1: bf cr7*4+2,2f
#ifdef __BIG_ENDIAN__
rotldi r9,r9,16
#endif
stex; sth r9,0(r3)
#ifdef __LITTLE_ENDIAN__
rotrdi r9,r9,16
#endif
addi r3,r3,2
2: bf cr7*4+3,3f
#ifdef __BIG_ENDIAN__
rotldi r9,r9,8
#endif
stex; stb r9,0(r3)
#ifdef __LITTLE_ENDIAN__
rotrdi r9,r9,8
#endif
3: li r3,0
blr
.Ldst_unaligned:
r3_offset = 0
PPC_MTOCRF(0x01,r6) /* put #bytes to 8B bdry into cr7 */
subf r5,r6,r5
li r7,0
cmpldi cr1,r5,16
bf cr7*4+3,1f
100: EX_TABLE(100b, .Lld_exc_r7)
lbz r0,0(r4)
100: EX_TABLE(100b, .Lst_exc_r7)
stb r0,0(r3)
addi r7,r7,1
1: bf cr7*4+2,2f
100: EX_TABLE(100b, .Lld_exc_r7)
lhzx r0,r7,r4
100: EX_TABLE(100b, .Lst_exc_r7)
sthx r0,r7,r3
addi r7,r7,2
2: bf cr7*4+1,3f
100: EX_TABLE(100b, .Lld_exc_r7)
lwzx r0,r7,r4
100: EX_TABLE(100b, .Lst_exc_r7)
stwx r0,r7,r3
3: PPC_MTOCRF(0x01,r5)
add r4,r6,r4
add r3,r6,r3
b .Ldst_aligned
.Lshort_copy:
r3_offset = 0
bf cr7*4+0,1f
lex; lwz r0,0(r4)
lex; lwz r9,4(r4)
addi r4,r4,8
stex; stw r0,0(r3)
stex; stw r9,4(r3)
addi r3,r3,8
1: bf cr7*4+1,2f
lex; lwz r0,0(r4)
addi r4,r4,4
stex; stw r0,0(r3)
addi r3,r3,4
2: bf cr7*4+2,3f
lex; lhz r0,0(r4)
addi r4,r4,2
stex; sth r0,0(r3)
addi r3,r3,2
3: bf cr7*4+3,4f
lex; lbz r0,0(r4)
stex; stb r0,0(r3)
4: li r3,0
blr
/*
* exception handlers follow
* we have to return the number of bytes not copied
* for an exception on a load, we set the rest of the destination to 0
* Note that the number of bytes of instructions for adjusting r3 needs
* to equal the amount of the adjustment, due to the trick of using
* .Lld_exc - r3_offset as the handler address.
*/
.Lld_exc_r7:
add r3,r3,r7
b .Lld_exc
/* adjust by 24 */
addi r3,r3,8
nop
/* adjust by 16 */
addi r3,r3,8
nop
/* adjust by 8 */
addi r3,r3,8
nop
/*
* Here we have had a fault on a load and r3 points to the first
* unmodified byte of the destination. We use the original arguments
* and r3 to work out how much wasn't copied. Since we load some
* distance ahead of the stores, we continue copying byte-by-byte until
* we hit the load fault again in order to copy as much as possible.
*/
.Lld_exc:
ld r6,-24(r1)
ld r4,-16(r1)
ld r5,-8(r1)
subf r6,r6,r3
add r4,r4,r6
subf r5,r6,r5 /* #bytes left to go */
/*
* first see if we can copy any more bytes before hitting another exception
*/
mtctr r5
r3_offset = 0
100: EX_TABLE(100b, .Ldone)
43: lbz r0,0(r4)
addi r4,r4,1
stex; stb r0,0(r3)
addi r3,r3,1
bdnz 43b
li r3,0 /* huh? all copied successfully this time? */
blr
/*
* here we have trapped again, amount remaining is in ctr.
*/
.Ldone:
mfctr r3
blr
/*
* exception handlers for stores: we need to work out how many bytes
* weren't copied, and we may need to copy some more.
* Note that the number of bytes of instructions for adjusting r3 needs
* to equal the amount of the adjustment, due to the trick of using
* .Lst_exc - r3_offset as the handler address.
*/
.Lst_exc_r7:
add r3,r3,r7
b .Lst_exc
/* adjust by 24 */
addi r3,r3,8
nop
/* adjust by 16 */
addi r3,r3,8
nop
/* adjust by 8 */
addi r3,r3,4
/* adjust by 4 */
addi r3,r3,4
.Lst_exc:
ld r6,-24(r1) /* original destination pointer */
ld r4,-16(r1) /* original source pointer */
ld r5,-8(r1) /* original number of bytes */
add r7,r6,r5
/*
* If the destination pointer isn't 8-byte aligned,
* we may have got the exception as a result of a
* store that overlapped a page boundary, so we may be
* able to copy a few more bytes.
*/
17: andi. r0,r3,7
beq 19f
subf r8,r6,r3 /* #bytes copied */
100: EX_TABLE(100b,19f)
lbzx r0,r8,r4
100: EX_TABLE(100b,19f)
stb r0,0(r3)
addi r3,r3,1
cmpld r3,r7
blt 17b
19: subf r3,r3,r7 /* #bytes not copied in r3 */
blr
/*
* Routine to copy a whole page of data, optimized for POWER4.
* On POWER4 it is more than 50% faster than the simple loop
* above (following the .Ldst_aligned label).
*/
.macro exc
100: EX_TABLE(100b, .Labort)
.endm
.Lcopy_page_4K:
std r31,-32(1)
std r30,-40(1)
std r29,-48(1)
std r28,-56(1)
std r27,-64(1)
std r26,-72(1)
std r25,-80(1)
std r24,-88(1)
std r23,-96(1)
std r22,-104(1)
std r21,-112(1)
std r20,-120(1)
li r5,4096/32 - 1
addi r3,r3,-8
li r0,5
0: addi r5,r5,-24
mtctr r0
exc; ld r22,640(4)
exc; ld r21,512(4)
exc; ld r20,384(4)
exc; ld r11,256(4)
exc; ld r9,128(4)
exc; ld r7,0(4)
exc; ld r25,648(4)
exc; ld r24,520(4)
exc; ld r23,392(4)
exc; ld r10,264(4)
exc; ld r8,136(4)
exc; ldu r6,8(4)
cmpwi r5,24
1:
exc; std r22,648(3)
exc; std r21,520(3)
exc; std r20,392(3)
exc; std r11,264(3)
exc; std r9,136(3)
exc; std r7,8(3)
exc; ld r28,648(4)
exc; ld r27,520(4)
exc; ld r26,392(4)
exc; ld r31,264(4)
exc; ld r30,136(4)
exc; ld r29,8(4)
exc; std r25,656(3)
exc; std r24,528(3)
exc; std r23,400(3)
exc; std r10,272(3)
exc; std r8,144(3)
exc; std r6,16(3)
exc; ld r22,656(4)
exc; ld r21,528(4)
exc; ld r20,400(4)
exc; ld r11,272(4)
exc; ld r9,144(4)
exc; ld r7,16(4)
exc; std r28,664(3)
exc; std r27,536(3)
exc; std r26,408(3)
exc; std r31,280(3)
exc; std r30,152(3)
exc; stdu r29,24(3)
exc; ld r25,664(4)
exc; ld r24,536(4)
exc; ld r23,408(4)
exc; ld r10,280(4)
exc; ld r8,152(4)
exc; ldu r6,24(4)
bdnz 1b
exc; std r22,648(3)
exc; std r21,520(3)
exc; std r20,392(3)
exc; std r11,264(3)
exc; std r9,136(3)
exc; std r7,8(3)
addi r4,r4,640
addi r3,r3,648
bge 0b
mtctr r5
exc; ld r7,0(4)
exc; ld r8,8(4)
exc; ldu r9,16(4)
3:
exc; ld r10,8(4)
exc; std r7,8(3)
exc; ld r7,16(4)
exc; std r8,16(3)
exc; ld r8,24(4)
exc; std r9,24(3)
exc; ldu r9,32(4)
exc; stdu r10,32(3)
bdnz 3b
4:
exc; ld r10,8(4)
exc; std r7,8(3)
exc; std r8,16(3)
exc; std r9,24(3)
exc; std r10,32(3)
9: ld r20,-120(1)
ld r21,-112(1)
ld r22,-104(1)
ld r23,-96(1)
ld r24,-88(1)
ld r25,-80(1)
ld r26,-72(1)
ld r27,-64(1)
ld r28,-56(1)
ld r29,-48(1)
ld r30,-40(1)
ld r31,-32(1)
li r3,0
blr
/*
* on an exception, reset to the beginning and jump back into the
* standard __copy_tofrom_user
*/
.Labort:
ld r20,-120(1)
ld r21,-112(1)
ld r22,-104(1)
ld r23,-96(1)
ld r24,-88(1)
ld r25,-80(1)
ld r26,-72(1)
ld r27,-64(1)
ld r28,-56(1)
ld r29,-48(1)
ld r30,-40(1)
ld r31,-32(1)
ld r3,-24(r1)
ld r4,-16(r1)
li r5,4096
b .Ldst_aligned
EXPORT_SYMBOL(__copy_tofrom_user)