496 lines
10 KiB
ArmAsm
496 lines
10 KiB
ArmAsm
/*
|
|
* INET An implementation of the TCP/IP protocol suite for the LINUX
|
|
* operating system. INET is implemented using the BSD Socket
|
|
* interface as the means of communication with the user level.
|
|
*
|
|
* IP/TCP/UDP checksumming routines
|
|
*
|
|
* Authors: Jorge Cwik, <jorge@laser.satlink.net>
|
|
* Arnt Gulbrandsen, <agulbra@nvg.unit.no>
|
|
* Tom May, <ftom@netcom.com>
|
|
* Pentium Pro/II routines:
|
|
* Alexander Kjeldaas <astor@guardian.no>
|
|
* Finn Arne Gangstad <finnag@guardian.no>
|
|
* Lots of code moved from tcp.c and ip.c; see those files
|
|
* for more names.
|
|
*
|
|
* Changes: Ingo Molnar, converted csum_partial_copy() to 2.1 exception
|
|
* handling.
|
|
* Andi Kleen, add zeroing on error
|
|
* converted to pure assembler
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#include <asm/errno.h>
|
|
|
|
/*
|
|
* computes a partial checksum, e.g. for TCP/UDP fragments
|
|
*/
|
|
|
|
/*
|
|
unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum)
|
|
*/
|
|
|
|
.text
|
|
.align 4
|
|
.globl csum_partial
|
|
|
|
#ifndef CONFIG_X86_USE_PPRO_CHECKSUM
|
|
|
|
/*
|
|
* Experiments with Ethernet and SLIP connections show that buff
|
|
* is aligned on either a 2-byte or 4-byte boundary. We get at
|
|
* least a twofold speedup on 486 and Pentium if it is 4-byte aligned.
|
|
* Fortunately, it is easy to convert 2-byte alignment to 4-byte
|
|
* alignment for the unrolled loop.
|
|
*/
|
|
csum_partial:
|
|
pushl %esi
|
|
pushl %ebx
|
|
movl 20(%esp),%eax # Function arg: unsigned int sum
|
|
movl 16(%esp),%ecx # Function arg: int len
|
|
movl 12(%esp),%esi # Function arg: unsigned char *buff
|
|
testl $3, %esi # Check alignment.
|
|
jz 2f # Jump if alignment is ok.
|
|
testl $1, %esi # Check alignment.
|
|
jz 10f # Jump if alignment is boundary of 2bytes.
|
|
|
|
# buf is odd
|
|
dec %ecx
|
|
jl 8f
|
|
movzbl (%esi), %ebx
|
|
adcl %ebx, %eax
|
|
roll $8, %eax
|
|
inc %esi
|
|
testl $2, %esi
|
|
jz 2f
|
|
10:
|
|
subl $2, %ecx # Alignment uses up two bytes.
|
|
jae 1f # Jump if we had at least two bytes.
|
|
addl $2, %ecx # ecx was < 2. Deal with it.
|
|
jmp 4f
|
|
1: movw (%esi), %bx
|
|
addl $2, %esi
|
|
addw %bx, %ax
|
|
adcl $0, %eax
|
|
2:
|
|
movl %ecx, %edx
|
|
shrl $5, %ecx
|
|
jz 2f
|
|
testl %esi, %esi
|
|
1: movl (%esi), %ebx
|
|
adcl %ebx, %eax
|
|
movl 4(%esi), %ebx
|
|
adcl %ebx, %eax
|
|
movl 8(%esi), %ebx
|
|
adcl %ebx, %eax
|
|
movl 12(%esi), %ebx
|
|
adcl %ebx, %eax
|
|
movl 16(%esi), %ebx
|
|
adcl %ebx, %eax
|
|
movl 20(%esi), %ebx
|
|
adcl %ebx, %eax
|
|
movl 24(%esi), %ebx
|
|
adcl %ebx, %eax
|
|
movl 28(%esi), %ebx
|
|
adcl %ebx, %eax
|
|
lea 32(%esi), %esi
|
|
dec %ecx
|
|
jne 1b
|
|
adcl $0, %eax
|
|
2: movl %edx, %ecx
|
|
andl $0x1c, %edx
|
|
je 4f
|
|
shrl $2, %edx # This clears CF
|
|
3: adcl (%esi), %eax
|
|
lea 4(%esi), %esi
|
|
dec %edx
|
|
jne 3b
|
|
adcl $0, %eax
|
|
4: andl $3, %ecx
|
|
jz 7f
|
|
cmpl $2, %ecx
|
|
jb 5f
|
|
movw (%esi),%cx
|
|
leal 2(%esi),%esi
|
|
je 6f
|
|
shll $16,%ecx
|
|
5: movb (%esi),%cl
|
|
6: addl %ecx,%eax
|
|
adcl $0, %eax
|
|
7:
|
|
testl $1, 12(%esp)
|
|
jz 8f
|
|
roll $8, %eax
|
|
8:
|
|
popl %ebx
|
|
popl %esi
|
|
ret
|
|
|
|
#else
|
|
|
|
/* Version for PentiumII/PPro */
|
|
|
|
csum_partial:
|
|
pushl %esi
|
|
pushl %ebx
|
|
movl 20(%esp),%eax # Function arg: unsigned int sum
|
|
movl 16(%esp),%ecx # Function arg: int len
|
|
movl 12(%esp),%esi # Function arg: const unsigned char *buf
|
|
|
|
testl $3, %esi
|
|
jnz 25f
|
|
10:
|
|
movl %ecx, %edx
|
|
movl %ecx, %ebx
|
|
andl $0x7c, %ebx
|
|
shrl $7, %ecx
|
|
addl %ebx,%esi
|
|
shrl $2, %ebx
|
|
negl %ebx
|
|
lea 45f(%ebx,%ebx,2), %ebx
|
|
testl %esi, %esi
|
|
jmp *%ebx
|
|
|
|
# Handle 2-byte-aligned regions
|
|
20: addw (%esi), %ax
|
|
lea 2(%esi), %esi
|
|
adcl $0, %eax
|
|
jmp 10b
|
|
25:
|
|
testl $1, %esi
|
|
jz 30f
|
|
# buf is odd
|
|
dec %ecx
|
|
jl 90f
|
|
movzbl (%esi), %ebx
|
|
addl %ebx, %eax
|
|
adcl $0, %eax
|
|
roll $8, %eax
|
|
inc %esi
|
|
testl $2, %esi
|
|
jz 10b
|
|
|
|
30: subl $2, %ecx
|
|
ja 20b
|
|
je 32f
|
|
addl $2, %ecx
|
|
jz 80f
|
|
movzbl (%esi),%ebx # csumming 1 byte, 2-aligned
|
|
addl %ebx, %eax
|
|
adcl $0, %eax
|
|
jmp 80f
|
|
32:
|
|
addw (%esi), %ax # csumming 2 bytes, 2-aligned
|
|
adcl $0, %eax
|
|
jmp 80f
|
|
|
|
40:
|
|
addl -128(%esi), %eax
|
|
adcl -124(%esi), %eax
|
|
adcl -120(%esi), %eax
|
|
adcl -116(%esi), %eax
|
|
adcl -112(%esi), %eax
|
|
adcl -108(%esi), %eax
|
|
adcl -104(%esi), %eax
|
|
adcl -100(%esi), %eax
|
|
adcl -96(%esi), %eax
|
|
adcl -92(%esi), %eax
|
|
adcl -88(%esi), %eax
|
|
adcl -84(%esi), %eax
|
|
adcl -80(%esi), %eax
|
|
adcl -76(%esi), %eax
|
|
adcl -72(%esi), %eax
|
|
adcl -68(%esi), %eax
|
|
adcl -64(%esi), %eax
|
|
adcl -60(%esi), %eax
|
|
adcl -56(%esi), %eax
|
|
adcl -52(%esi), %eax
|
|
adcl -48(%esi), %eax
|
|
adcl -44(%esi), %eax
|
|
adcl -40(%esi), %eax
|
|
adcl -36(%esi), %eax
|
|
adcl -32(%esi), %eax
|
|
adcl -28(%esi), %eax
|
|
adcl -24(%esi), %eax
|
|
adcl -20(%esi), %eax
|
|
adcl -16(%esi), %eax
|
|
adcl -12(%esi), %eax
|
|
adcl -8(%esi), %eax
|
|
adcl -4(%esi), %eax
|
|
45:
|
|
lea 128(%esi), %esi
|
|
adcl $0, %eax
|
|
dec %ecx
|
|
jge 40b
|
|
movl %edx, %ecx
|
|
50: andl $3, %ecx
|
|
jz 80f
|
|
|
|
# Handle the last 1-3 bytes without jumping
|
|
notl %ecx # 1->2, 2->1, 3->0, higher bits are masked
|
|
movl $0xffffff,%ebx # by the shll and shrl instructions
|
|
shll $3,%ecx
|
|
shrl %cl,%ebx
|
|
andl -128(%esi),%ebx # esi is 4-aligned so should be ok
|
|
addl %ebx,%eax
|
|
adcl $0,%eax
|
|
80:
|
|
testl $1, 12(%esp)
|
|
jz 90f
|
|
roll $8, %eax
|
|
90:
|
|
popl %ebx
|
|
popl %esi
|
|
ret
|
|
|
|
#endif
|
|
|
|
/*
|
|
unsigned int csum_partial_copy_generic (const char *src, char *dst,
|
|
int len, int sum, int *src_err_ptr, int *dst_err_ptr)
|
|
*/
|
|
|
|
/*
|
|
* Copy from ds while checksumming, otherwise like csum_partial
|
|
*
|
|
* The macros SRC and DST specify the type of access for the instruction.
|
|
* thus we can call a custom exception handler for all access types.
|
|
*
|
|
* FIXME: could someone double-check whether I haven't mixed up some SRC and
|
|
* DST definitions? It's damn hard to trigger all cases. I hope I got
|
|
* them all but there's no guarantee.
|
|
*/
|
|
|
|
#define SRC(y...) \
|
|
9999: y; \
|
|
.section __ex_table, "a"; \
|
|
.long 9999b, 6001f ; \
|
|
.previous
|
|
|
|
#define DST(y...) \
|
|
9999: y; \
|
|
.section __ex_table, "a"; \
|
|
.long 9999b, 6002f ; \
|
|
.previous
|
|
|
|
.align 4
|
|
.globl csum_partial_copy_generic
|
|
|
|
#ifndef CONFIG_X86_USE_PPRO_CHECKSUM
|
|
|
|
#define ARGBASE 16
|
|
#define FP 12
|
|
|
|
csum_partial_copy_generic:
|
|
subl $4,%esp
|
|
pushl %edi
|
|
pushl %esi
|
|
pushl %ebx
|
|
movl ARGBASE+16(%esp),%eax # sum
|
|
movl ARGBASE+12(%esp),%ecx # len
|
|
movl ARGBASE+4(%esp),%esi # src
|
|
movl ARGBASE+8(%esp),%edi # dst
|
|
|
|
testl $2, %edi # Check alignment.
|
|
jz 2f # Jump if alignment is ok.
|
|
subl $2, %ecx # Alignment uses up two bytes.
|
|
jae 1f # Jump if we had at least two bytes.
|
|
addl $2, %ecx # ecx was < 2. Deal with it.
|
|
jmp 4f
|
|
SRC(1: movw (%esi), %bx )
|
|
addl $2, %esi
|
|
DST( movw %bx, (%edi) )
|
|
addl $2, %edi
|
|
addw %bx, %ax
|
|
adcl $0, %eax
|
|
2:
|
|
movl %ecx, FP(%esp)
|
|
shrl $5, %ecx
|
|
jz 2f
|
|
testl %esi, %esi
|
|
SRC(1: movl (%esi), %ebx )
|
|
SRC( movl 4(%esi), %edx )
|
|
adcl %ebx, %eax
|
|
DST( movl %ebx, (%edi) )
|
|
adcl %edx, %eax
|
|
DST( movl %edx, 4(%edi) )
|
|
|
|
SRC( movl 8(%esi), %ebx )
|
|
SRC( movl 12(%esi), %edx )
|
|
adcl %ebx, %eax
|
|
DST( movl %ebx, 8(%edi) )
|
|
adcl %edx, %eax
|
|
DST( movl %edx, 12(%edi) )
|
|
|
|
SRC( movl 16(%esi), %ebx )
|
|
SRC( movl 20(%esi), %edx )
|
|
adcl %ebx, %eax
|
|
DST( movl %ebx, 16(%edi) )
|
|
adcl %edx, %eax
|
|
DST( movl %edx, 20(%edi) )
|
|
|
|
SRC( movl 24(%esi), %ebx )
|
|
SRC( movl 28(%esi), %edx )
|
|
adcl %ebx, %eax
|
|
DST( movl %ebx, 24(%edi) )
|
|
adcl %edx, %eax
|
|
DST( movl %edx, 28(%edi) )
|
|
|
|
lea 32(%esi), %esi
|
|
lea 32(%edi), %edi
|
|
dec %ecx
|
|
jne 1b
|
|
adcl $0, %eax
|
|
2: movl FP(%esp), %edx
|
|
movl %edx, %ecx
|
|
andl $0x1c, %edx
|
|
je 4f
|
|
shrl $2, %edx # This clears CF
|
|
SRC(3: movl (%esi), %ebx )
|
|
adcl %ebx, %eax
|
|
DST( movl %ebx, (%edi) )
|
|
lea 4(%esi), %esi
|
|
lea 4(%edi), %edi
|
|
dec %edx
|
|
jne 3b
|
|
adcl $0, %eax
|
|
4: andl $3, %ecx
|
|
jz 7f
|
|
cmpl $2, %ecx
|
|
jb 5f
|
|
SRC( movw (%esi), %cx )
|
|
leal 2(%esi), %esi
|
|
DST( movw %cx, (%edi) )
|
|
leal 2(%edi), %edi
|
|
je 6f
|
|
shll $16,%ecx
|
|
SRC(5: movb (%esi), %cl )
|
|
DST( movb %cl, (%edi) )
|
|
6: addl %ecx, %eax
|
|
adcl $0, %eax
|
|
7:
|
|
5000:
|
|
|
|
# Exception handler:
|
|
.section .fixup, "ax"
|
|
|
|
6001:
|
|
movl ARGBASE+20(%esp), %ebx # src_err_ptr
|
|
movl $-EFAULT, (%ebx)
|
|
|
|
# zero the complete destination - computing the rest
|
|
# is too much work
|
|
movl ARGBASE+8(%esp), %edi # dst
|
|
movl ARGBASE+12(%esp), %ecx # len
|
|
xorl %eax,%eax
|
|
rep ; stosb
|
|
|
|
jmp 5000b
|
|
|
|
6002:
|
|
movl ARGBASE+24(%esp), %ebx # dst_err_ptr
|
|
movl $-EFAULT,(%ebx)
|
|
jmp 5000b
|
|
|
|
.previous
|
|
|
|
popl %ebx
|
|
popl %esi
|
|
popl %edi
|
|
popl %ecx # equivalent to addl $4,%esp
|
|
ret
|
|
|
|
#else
|
|
|
|
/* Version for PentiumII/PPro */
|
|
|
|
#define ROUND1(x) \
|
|
SRC(movl x(%esi), %ebx ) ; \
|
|
addl %ebx, %eax ; \
|
|
DST(movl %ebx, x(%edi) ) ;
|
|
|
|
#define ROUND(x) \
|
|
SRC(movl x(%esi), %ebx ) ; \
|
|
adcl %ebx, %eax ; \
|
|
DST(movl %ebx, x(%edi) ) ;
|
|
|
|
#define ARGBASE 12
|
|
|
|
csum_partial_copy_generic:
|
|
pushl %ebx
|
|
pushl %edi
|
|
pushl %esi
|
|
movl ARGBASE+4(%esp),%esi #src
|
|
movl ARGBASE+8(%esp),%edi #dst
|
|
movl ARGBASE+12(%esp),%ecx #len
|
|
movl ARGBASE+16(%esp),%eax #sum
|
|
# movl %ecx, %edx
|
|
movl %ecx, %ebx
|
|
movl %esi, %edx
|
|
shrl $6, %ecx
|
|
andl $0x3c, %ebx
|
|
negl %ebx
|
|
subl %ebx, %esi
|
|
subl %ebx, %edi
|
|
lea -1(%esi),%edx
|
|
andl $-32,%edx
|
|
lea 3f(%ebx,%ebx), %ebx
|
|
testl %esi, %esi
|
|
jmp *%ebx
|
|
1: addl $64,%esi
|
|
addl $64,%edi
|
|
SRC(movb -32(%edx),%bl) ; SRC(movb (%edx),%bl)
|
|
ROUND1(-64) ROUND(-60) ROUND(-56) ROUND(-52)
|
|
ROUND (-48) ROUND(-44) ROUND(-40) ROUND(-36)
|
|
ROUND (-32) ROUND(-28) ROUND(-24) ROUND(-20)
|
|
ROUND (-16) ROUND(-12) ROUND(-8) ROUND(-4)
|
|
3: adcl $0,%eax
|
|
addl $64, %edx
|
|
dec %ecx
|
|
jge 1b
|
|
4: movl ARGBASE+12(%esp),%edx #len
|
|
andl $3, %edx
|
|
jz 7f
|
|
cmpl $2, %edx
|
|
jb 5f
|
|
SRC( movw (%esi), %dx )
|
|
leal 2(%esi), %esi
|
|
DST( movw %dx, (%edi) )
|
|
leal 2(%edi), %edi
|
|
je 6f
|
|
shll $16,%edx
|
|
5:
|
|
SRC( movb (%esi), %dl )
|
|
DST( movb %dl, (%edi) )
|
|
6: addl %edx, %eax
|
|
adcl $0, %eax
|
|
7:
|
|
.section .fixup, "ax"
|
|
6001: movl ARGBASE+20(%esp), %ebx # src_err_ptr
|
|
movl $-EFAULT, (%ebx)
|
|
# zero the complete destination (computing the rest is too much work)
|
|
movl ARGBASE+8(%esp),%edi # dst
|
|
movl ARGBASE+12(%esp),%ecx # len
|
|
xorl %eax,%eax
|
|
rep; stosb
|
|
jmp 7b
|
|
6002: movl ARGBASE+24(%esp), %ebx # dst_err_ptr
|
|
movl $-EFAULT, (%ebx)
|
|
jmp 7b
|
|
.previous
|
|
|
|
popl %esi
|
|
popl %edi
|
|
popl %ebx
|
|
ret
|
|
|
|
#undef ROUND
|
|
#undef ROUND1
|
|
|
|
#endif
|