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|
/*
* linux/arch/arm/lib/csumpartialcopyuser.S
*
* Copyright (C) 1995-1998 Russell King
*/
#include <linux/config.h>
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/errno.h>
#include "constants.h"
.text
/* Function: __u32 csum_partial_copy_from_user (const char *src, char *dst, int len, __u32 sum, int *err_ptr)
* Params : r0 = src, r1 = dst, r2 = len, r3 = sum, [sp, #0] = &err
* Returns : r0 = checksum, [[sp, #0], #0] = 0 or -EFAULT
*/
#if defined(CONFIG_CPU_32)
.macro save_regs
stmfd sp!, {r1 - r2, r4 - r8, fp, ip, lr, pc}
.endm
.macro load_regs,flags
ldm\flags fp, {r1, r2, r4-r8, fp, sp, pc}
.endm
.macro load1b, reg1
9999: ldrbt \reg1, [r0], $1
.section __ex_table, "a"
.align 3
.long 9999b, 6001f
.previous
.endm
.macro load2b, reg1, reg2
9999: ldrbt \reg1, [r0], $1
9998: ldrbt \reg2, [r0], $1
.section __ex_table, "a"
.long 9999b, 6001f
.long 9998b, 6001f
.previous
.endm
.macro load1l, reg1
9999: ldrt \reg1, [r0], $4
.section __ex_table, "a"
.align 3
.long 9999b, 6001f
.previous
.endm
.macro load2l, reg1, reg2
9999: ldrt \reg1, [r0], $4
9998: ldrt \reg2, [r0], $4
.section __ex_table, "a"
.long 9999b, 6001f
.long 9998b, 6001f
.previous
.endm
.macro load4l, reg1, reg2, reg3, reg4
9999: ldrt \reg1, [r0], $4
9998: ldrt \reg2, [r0], $4
9997: ldrt \reg3, [r0], $4
9996: ldrt \reg4, [r0], $4
.section __ex_table, "a"
.long 9999b, 6001f
.long 9998b, 6001f
.long 9997b, 6001f
.long 9996b, 6001f
.previous
.endm
#elif defined(CONFIG_CPU_26)
.macro save_regs
stmfd sp!, {r1 - r2, r4 - r9, fp, ip, lr, pc}
mov r9, sp, lsr #13
mov r9, r9, lsl #13
ldr r9, [r9, #TSK_ADDR_LIMIT]
mov r9, r9, lsr #24
.endm
.macro load_regs,flags
ldm\flags fp, {r1, r2, r4-r9, fp, sp, pc}^
.endm
.macro load1b, reg1
tst r9, #0x01
9999: ldreqbt \reg1, [r0], #1
ldrneb \reg1, [r0], #1
.section __ex_table, "a"
.align 3
.long 9999b, 6001f
.previous
.endm
.macro load2b, reg1, reg2
tst r9, #0x01
9999: ldreqbt \reg1, [r0], #1
ldrneb \reg1, [r0], #1
9998: ldreqbt \reg2, [r0], #1
ldrneb \reg2, [r0], #1
.section __ex_table, "a"
.long 9999b, 6001f
.long 9998b, 6001f
.previous
.endm
.macro load1l, reg1
tst r9, #0x01
9999: ldreqt \reg1, [r0], #4
ldrne \reg1, [r0], #4
.section __ex_table, "a"
.align 3
.long 9999b, 6001f
.previous
.endm
.macro load2l, reg1, reg2
tst r9, #0x01
ldmneia r0!, {\reg1, \reg2}
9999: ldreqt \reg1, [r0], #4
9998: ldreqt \reg2, [r0], #4
.section __ex_table, "a"
.long 9999b, 6001f
.long 9998b, 6001f
.previous
.endm
.macro load4l, reg1, reg2, reg3, reg4
tst r9, #0x01
ldmneia r0!, {\reg1, \reg2, \reg3, \reg4}
9999: ldreqt \reg1, [r0], #4
9998: ldreqt \reg2, [r0], #4
9997: ldreqt \reg3, [r0], #4
9996: ldreqt \reg4, [r0], #4
.section __ex_table, "a"
.long 9999b, 6001f
.long 9998b, 6001f
.long 9997b, 6001f
.long 9996b, 6001f
.previous
.endm
#else
#error Unknown CPU architecture
#endif
ENTRY(csum_partial_copy_from_user)
mov ip, sp
save_regs
sub fp, ip, #4
cmp r2, #4
blt .too_small_user
tst r1, #2 @ Test destination alignment
beq .dst_aligned_user
load2b ip, r8
subs r2, r2, #2 @ We do not know if SRC is aligned...
orr ip, ip, r8, lsl #8
adds r3, r3, ip
adcs r3, r3, #0
strb ip, [r1], #1
mov ip, ip, lsr #8
strb ip, [r1], #1 @ Destination now aligned
.dst_aligned_user:
tst r0, #3
bne .src_not_aligned_user
adds r3, r3, #0
bics ip, r2, #15 @ Routine for src & dst aligned
beq 2f
1: load4l r4, r5, r6, r7
stmia r1!, {r4, r5, r6, r7}
adcs r3, r3, r4
adcs r3, r3, r5
adcs r3, r3, r6
adcs r3, r3, r7
sub ip, ip, #16
teq ip, #0
bne 1b
2: ands ip, r2, #12
beq 4f
tst ip, #8
beq 3f
load2l r4, r5
stmia r1!, {r4, r5}
adcs r3, r3, r4
adcs r3, r3, r5
tst ip, #4
beq 4f
3: load1l r4
str r4, [r1], #4
adcs r3, r3, r4
4: ands r2, r2, #3
adceq r0, r3, #0
load_regs eqea
load1l r4
tst r2, #2
beq .exit
adcs r3, r3, r4, lsl #16
strb r4, [r1], #1
mov r4, r4, lsr #8
strb r4, [r1], #1
mov r4, r4, lsr #8
.exit: tst r2, #1
strneb r4, [r1], #1
andne r4, r4, #255
adcnes r3, r3, r4
adcs r0, r3, #0
load_regs ea
.too_small_user:
teq r2, #0
load_regs eqea
cmp r2, #2
blt .too_small_user1
load2b ip, r8
orr ip, ip, r8, lsl #8
adds r3, r3, ip
strb ip, [r1], #1
strb r8, [r1], #1
tst r2, #1
.too_small_user1: @ C = 0
beq .csum_exit
load1b ip
strb ip, [r1], #1
adcs r3, r3, ip
.csum_exit: adc r0, r3, #0
load_regs ea
.src_not_aligned_user:
cmp r2, #4
blt .too_small_user
and ip, r0, #3
bic r0, r0, #3
load1l r4
cmp ip, #2
beq .src2_aligned_user
bhi .src3_aligned_user
mov r4, r4, lsr #8
adds r3, r3, #0
bics ip, r2, #15
beq 2f
1: load4l r5, r6, r7, r8
orr r4, r4, r5, lsl #24
mov r5, r5, lsr #8
orr r5, r5, r6, lsl #24
mov r6, r6, lsr #8
orr r6, r6, r7, lsl #24
mov r7, r7, lsr #8
orr r7, r7, r8, lsl #24
stmia r1!, {r4, r5, r6, r7}
adcs r3, r3, r4
adcs r3, r3, r5
adcs r3, r3, r6
adcs r3, r3, r7
mov r4, r8, lsr #8
sub ip, ip, #16
teq ip, #0
bne 1b
2: ands ip, r2, #12
beq 4f
tst ip, #8
beq 3f
load2l r5, r6
orr r4, r4, r5, lsl #24
mov r5, r5, lsr #8
orr r5, r5, r6, lsl #24
stmia r1!, {r4, r5}
adcs r3, r3, r4
adcs r3, r3, r5
mov r4, r6, lsr #8
tst ip, #4
beq 4f
3: load1l r5
orr r4, r4, r5, lsl #24
str r4, [r1], #4
adcs r3, r3, r4
mov r4, r5, lsr #8
4: ands r2, r2, #3
adceq r0, r3, #0
load_regs eqea
tst r2, #2
beq .exit
adcs r3, r3, r4, lsl #16
strb r4, [r1], #1
mov r4, r4, lsr #8
strb r4, [r1], #1
mov r4, r4, lsr #8
b .exit
.src2_aligned_user:
mov r4, r4, lsr #16
adds r3, r3, #0
bics ip, r2, #15
beq 2f
1: load4l r5, r6, r7, r8
orr r4, r4, r5, lsl #16
mov r5, r5, lsr #16
orr r5, r5, r6, lsl #16
mov r6, r6, lsr #16
orr r6, r6, r7, lsl #16
mov r7, r7, lsr #16
orr r7, r7, r8, lsl #16
stmia r1!, {r4, r5, r6, r7}
adcs r3, r3, r4
adcs r3, r3, r5
adcs r3, r3, r6
adcs r3, r3, r7
mov r4, r8, lsr #16
sub ip, ip, #16
teq ip, #0
bne 1b
2: ands ip, r2, #12
beq 4f
tst ip, #8
beq 3f
load2l r5, r6
orr r4, r4, r5, lsl #16
mov r5, r5, lsr #16
orr r5, r5, r6, lsl #16
stmia r1!, {r4, r5}
adcs r3, r3, r4
adcs r3, r3, r5
mov r4, r6, lsr #16
tst ip, #4
beq 4f
3: load1l r5
orr r4, r4, r5, lsl #16
str r4, [r1], #4
adcs r3, r3, r4
mov r4, r5, lsr #16
4: ands r2, r2, #3
adceq r0, r3, #0
load_regs eqea
tst r2, #2
beq .exit
adcs r3, r3, r4, lsl #16
strb r4, [r1], #1
mov r4, r4, lsr #8
strb r4, [r1], #1
tst r2, #1
adceq r0, r3, #0
load_regs eqea
load1b r4
b .exit
.src3_aligned_user:
mov r4, r4, lsr #24
adds r3, r3, #0
bics ip, r2, #15
beq 2f
1: load4l r5, r6, r7, r8
orr r4, r4, r5, lsl #8
mov r5, r5, lsr #24
orr r5, r5, r6, lsl #8
mov r6, r6, lsr #24
orr r6, r6, r7, lsl #8
mov r7, r7, lsr #24
orr r7, r7, r8, lsl #8
stmia r1!, {r4, r5, r6, r7}
adcs r3, r3, r4
adcs r3, r3, r5
adcs r3, r3, r6
adcs r3, r3, r7
mov r4, r8, lsr #24
sub ip, ip, #16
teq ip, #0
bne 1b
2: ands ip, r2, #12
beq 4f
tst ip, #8
beq 3f
load2l r5, r6
orr r4, r4, r5, lsl #8
mov r5, r5, lsr #24
orr r5, r5, r6, lsl #8
stmia r1!, {r4, r5}
adcs r3, r3, r4
adcs r3, r3, r5
mov r4, r6, lsr #24
tst ip, #4
beq 4f
3: load1l r5
orr r4, r4, r5, lsl #8
str r4, [r1], #4
adcs r3, r3, r4
mov r4, r5, lsr #24
4: ands r2, r2, #3
adceq r0, r3, #0
load_regs eqea
tst r2, #2
beq .exit
adcs r3, r3, r4, lsl #16
strb r4, [r1], #1
load1l r4
strb r4, [r1], #1
adcs r3, r3, r4, lsl #24
mov r4, r4, lsr #8
b .exit
#if defined(CONFIG_CPU_32)
.section .fixup,"ax"
#endif
.align 4
6001: mov r4, #-EFAULT
ldr r5, [fp, #4]
str r4, [r5]
ldmia sp, {r1, r2} @ retrieve original arguments
add r2, r2, r1
mov r3, #0 @ zero the buffer
6002: teq r2, r1
strneb r3, [r1], #1
bne 6002b
load_regs ea
#if defined(CONFIG_CPU_32)
.previous
#endif
|
