1118 lines
21 KiB
ArmAsm
1118 lines
21 KiB
ArmAsm
/*-
|
|
* Copyright (c) 1993 The Regents of the University of California.
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by the University of
|
|
* California, Berkeley and its contributors.
|
|
* 4. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* $Id: support.s,v 1.18 1994/09/16 13:33:27 davidg Exp $
|
|
*/
|
|
|
|
#include "assym.s" /* system definitions */
|
|
#include "errno.h" /* error return codes */
|
|
#include "machine/asmacros.h" /* miscellaneous asm macros */
|
|
#include "machine/cputypes.h" /* types of CPUs */
|
|
|
|
#define KDSEL 0x10 /* kernel data selector */
|
|
#define IDXSHIFT 10
|
|
|
|
/*
|
|
* Support routines for GCC, general C-callable functions
|
|
*/
|
|
ENTRY(__udivsi3)
|
|
movl 4(%esp),%eax
|
|
xorl %edx,%edx
|
|
divl 8(%esp)
|
|
ret
|
|
|
|
ENTRY(__divsi3)
|
|
movl 4(%esp),%eax
|
|
cltd
|
|
idivl 8(%esp)
|
|
ret
|
|
|
|
/*
|
|
* Support for reading real time clock registers
|
|
*/
|
|
ENTRY(rtcin) /* rtcin(val) */
|
|
movl 4(%esp),%eax
|
|
outb %al,$0x70
|
|
NOP
|
|
xorl %eax,%eax
|
|
inb $0x71,%al
|
|
NOP
|
|
ret
|
|
|
|
/*
|
|
* bcopy family
|
|
*/
|
|
|
|
/*
|
|
* void bzero(void *base, u_int cnt)
|
|
* Special code for I486 because stosl uses lots
|
|
* of clocks. Makes little or no difference on DX2 type
|
|
* machines, but stosl is about 1/2 as fast as
|
|
* memory moves on a standard DX !!!!!
|
|
*/
|
|
ALTENTRY(blkclr)
|
|
ENTRY(bzero)
|
|
#if defined(I486_CPU)
|
|
cmpl $CPUCLASS_486,_cpu_class
|
|
jz 1f
|
|
#endif
|
|
|
|
pushl %edi
|
|
movl 8(%esp),%edi
|
|
movl 12(%esp),%ecx
|
|
xorl %eax,%eax
|
|
shrl $2,%ecx
|
|
cld
|
|
rep
|
|
stosl
|
|
movl 12(%esp),%ecx
|
|
andl $3,%ecx
|
|
rep
|
|
stosb
|
|
popl %edi
|
|
ret
|
|
|
|
#if defined(I486_CPU)
|
|
SUPERALIGN_TEXT
|
|
1:
|
|
movl 4(%esp),%edx
|
|
movl 8(%esp),%ecx
|
|
xorl %eax,%eax
|
|
/
|
|
/ do 64 byte chunks first
|
|
/
|
|
/ XXX this is probably over-unrolled at least for DX2's
|
|
/
|
|
2:
|
|
cmpl $64,%ecx
|
|
jb 3f
|
|
movl %eax,(%edx)
|
|
movl %eax,4(%edx)
|
|
movl %eax,8(%edx)
|
|
movl %eax,12(%edx)
|
|
movl %eax,16(%edx)
|
|
movl %eax,20(%edx)
|
|
movl %eax,24(%edx)
|
|
movl %eax,28(%edx)
|
|
movl %eax,32(%edx)
|
|
movl %eax,36(%edx)
|
|
movl %eax,40(%edx)
|
|
movl %eax,44(%edx)
|
|
movl %eax,48(%edx)
|
|
movl %eax,52(%edx)
|
|
movl %eax,56(%edx)
|
|
movl %eax,60(%edx)
|
|
addl $64,%edx
|
|
subl $64,%ecx
|
|
jnz 2b
|
|
ret
|
|
|
|
/
|
|
/ do 16 byte chunks
|
|
/
|
|
SUPERALIGN_TEXT
|
|
3:
|
|
cmpl $16,%ecx
|
|
jb 4f
|
|
movl %eax,(%edx)
|
|
movl %eax,4(%edx)
|
|
movl %eax,8(%edx)
|
|
movl %eax,12(%edx)
|
|
addl $16,%edx
|
|
subl $16,%ecx
|
|
jnz 3b
|
|
ret
|
|
|
|
/
|
|
/ do 4 byte chunks
|
|
/
|
|
SUPERALIGN_TEXT
|
|
4:
|
|
cmpl $4,%ecx
|
|
jb 5f
|
|
movl %eax,(%edx)
|
|
addl $4,%edx
|
|
subl $4,%ecx
|
|
jnz 4b
|
|
ret
|
|
|
|
/
|
|
/ do 1 byte chunks
|
|
/ a jump table seems to be faster than a loop or more range reductions
|
|
/
|
|
/ XXX need a const section for non-text
|
|
/
|
|
SUPERALIGN_TEXT
|
|
jtab:
|
|
.long do0
|
|
.long do1
|
|
.long do2
|
|
.long do3
|
|
|
|
SUPERALIGN_TEXT
|
|
5:
|
|
jmp jtab(,%ecx,4)
|
|
|
|
SUPERALIGN_TEXT
|
|
do3:
|
|
movw %ax,(%edx)
|
|
movb %al,2(%edx)
|
|
ret
|
|
|
|
SUPERALIGN_TEXT
|
|
do2:
|
|
movw %ax,(%edx)
|
|
ret
|
|
|
|
SUPERALIGN_TEXT
|
|
do1:
|
|
movb %al,(%edx)
|
|
|
|
SUPERALIGN_TEXT
|
|
do0:
|
|
ret
|
|
#endif /* I486_CPU */
|
|
|
|
/* fillw(pat, base, cnt) */
|
|
ENTRY(fillw)
|
|
pushl %edi
|
|
movl 8(%esp),%eax
|
|
movl 12(%esp),%edi
|
|
movl 16(%esp),%ecx
|
|
cld
|
|
rep
|
|
stosw
|
|
popl %edi
|
|
ret
|
|
|
|
/* filli(pat, base, cnt) */
|
|
ENTRY(filli)
|
|
pushl %edi
|
|
movl 8(%esp),%eax
|
|
movl 12(%esp),%edi
|
|
movl 16(%esp),%ecx
|
|
cld
|
|
rep
|
|
stosl
|
|
popl %edi
|
|
ret
|
|
|
|
ENTRY(bcopyb)
|
|
bcopyb:
|
|
pushl %esi
|
|
pushl %edi
|
|
movl 12(%esp),%esi
|
|
movl 16(%esp),%edi
|
|
movl 20(%esp),%ecx
|
|
cmpl %esi,%edi /* potentially overlapping? */
|
|
jnb 1f
|
|
cld /* nope, copy forwards */
|
|
rep
|
|
movsb
|
|
popl %edi
|
|
popl %esi
|
|
ret
|
|
|
|
ALIGN_TEXT
|
|
1:
|
|
addl %ecx,%edi /* copy backwards. */
|
|
addl %ecx,%esi
|
|
std
|
|
decl %edi
|
|
decl %esi
|
|
rep
|
|
movsb
|
|
popl %edi
|
|
popl %esi
|
|
cld
|
|
ret
|
|
|
|
ENTRY(bcopyw)
|
|
bcopyw:
|
|
pushl %esi
|
|
pushl %edi
|
|
movl 12(%esp),%esi
|
|
movl 16(%esp),%edi
|
|
movl 20(%esp),%ecx
|
|
cmpl %esi,%edi /* potentially overlapping? */
|
|
jnb 1f
|
|
shrl $1,%ecx /* copy by 16-bit words */
|
|
cld /* nope, copy forwards */
|
|
rep
|
|
movsw
|
|
adc %ecx,%ecx /* any bytes left? */
|
|
rep
|
|
movsb
|
|
popl %edi
|
|
popl %esi
|
|
ret
|
|
|
|
ALIGN_TEXT
|
|
1:
|
|
addl %ecx,%edi /* copy backwards */
|
|
addl %ecx,%esi
|
|
andl $1,%ecx /* any fractional bytes? */
|
|
decl %edi
|
|
decl %esi
|
|
std
|
|
rep
|
|
movsb
|
|
movl 20(%esp),%ecx /* copy remainder by 16-bit words */
|
|
shrl $1,%ecx
|
|
decl %esi
|
|
decl %edi
|
|
rep
|
|
movsw
|
|
popl %edi
|
|
popl %esi
|
|
cld
|
|
ret
|
|
|
|
ENTRY(bcopyx)
|
|
movl 16(%esp),%eax
|
|
cmpl $2,%eax
|
|
je bcopyw /* not _bcopyw, to avoid multiple mcounts */
|
|
cmpl $4,%eax
|
|
je bcopy /* XXX the shared ret's break mexitcount */
|
|
jmp bcopyb
|
|
|
|
/*
|
|
* (ov)bcopy(src, dst, cnt)
|
|
* ws@tools.de (Wolfgang Solfrank, TooLs GmbH) +49-228-985800
|
|
*/
|
|
ALTENTRY(ovbcopy)
|
|
ENTRY(bcopy)
|
|
bcopy:
|
|
pushl %esi
|
|
pushl %edi
|
|
movl 12(%esp),%esi
|
|
movl 16(%esp),%edi
|
|
movl 20(%esp),%ecx
|
|
cmpl %esi,%edi /* potentially overlapping? */
|
|
jnb 1f
|
|
shrl $2,%ecx /* copy by 32-bit words */
|
|
cld /* nope, copy forwards */
|
|
rep
|
|
movsl
|
|
movl 20(%esp),%ecx
|
|
andl $3,%ecx /* any bytes left? */
|
|
rep
|
|
movsb
|
|
popl %edi
|
|
popl %esi
|
|
ret
|
|
|
|
ALIGN_TEXT
|
|
1:
|
|
addl %ecx,%edi /* copy backwards */
|
|
addl %ecx,%esi
|
|
andl $3,%ecx /* any fractional bytes? */
|
|
decl %edi
|
|
decl %esi
|
|
std
|
|
rep
|
|
movsb
|
|
movl 20(%esp),%ecx /* copy remainder by 32-bit words */
|
|
shrl $2,%ecx
|
|
subl $3,%esi
|
|
subl $3,%edi
|
|
rep
|
|
movsl
|
|
popl %edi
|
|
popl %esi
|
|
cld
|
|
ret
|
|
|
|
|
|
/*****************************************************************************/
|
|
/* copyout and fubyte family */
|
|
/*****************************************************************************/
|
|
/*
|
|
* Access user memory from inside the kernel. These routines and possibly
|
|
* the math- and DOS emulators should be the only places that do this.
|
|
*
|
|
* We have to access the memory with user's permissions, so use a segment
|
|
* selector with RPL 3. For writes to user space we have to additionally
|
|
* check the PTE for write permission, because the 386 does not check
|
|
* write permissions when we are executing with EPL 0. The 486 does check
|
|
* this if the WP bit is set in CR0, so we can use a simpler version here.
|
|
*
|
|
* These routines set curpcb->onfault for the time they execute. When a
|
|
* protection violation occurs inside the functions, the trap handler
|
|
* returns to *curpcb->onfault instead of the function.
|
|
*/
|
|
|
|
|
|
ENTRY(copyout) /* copyout(from_kernel, to_user, len) */
|
|
movl _curpcb,%eax
|
|
movl $copyout_fault,PCB_ONFAULT(%eax)
|
|
pushl %esi
|
|
pushl %edi
|
|
pushl %ebx
|
|
movl 16(%esp),%esi
|
|
movl 20(%esp),%edi
|
|
movl 24(%esp),%ebx
|
|
orl %ebx,%ebx /* anything to do? */
|
|
jz done_copyout
|
|
|
|
/*
|
|
* Check explicitly for non-user addresses. If 486 write protection
|
|
* is being used, this check is essential because we are in kernel
|
|
* mode so the h/w does not provide any protection against writing
|
|
* kernel addresses.
|
|
*
|
|
* Otherwise, it saves having to load and restore %es to get the
|
|
* usual segment-based protection (the destination segment for movs
|
|
* is always %es). The other explicit checks for user-writablility
|
|
* are not quite sufficient. They fail for the user area because
|
|
* we mapped the user area read/write to avoid having an #ifdef in
|
|
* vm_machdep.c. They fail for user PTEs and/or PTDs! (107
|
|
* addresses including 0xff800000 and 0xfc000000). I'm not sure if
|
|
* this can be fixed. Marking the PTEs supervisor mode and the
|
|
* PDE's user mode would almost work, but there may be a problem
|
|
* with the self-referential PDE.
|
|
*/
|
|
movl %edi,%eax
|
|
addl %ebx,%eax
|
|
jc copyout_fault
|
|
/*
|
|
* XXX STOP USING VM_MAXUSER_ADDRESS.
|
|
* It is an end address, not a max, so every time it is used correctly it
|
|
* looks like there is an off by one error, and of course it caused an off
|
|
* by one error in several places.
|
|
*/
|
|
cmpl $VM_MAXUSER_ADDRESS,%eax
|
|
ja copyout_fault
|
|
|
|
#if defined(I386_CPU)
|
|
|
|
#if defined(I486_CPU) || defined(I586_CPU)
|
|
cmpl $CPUCLASS_386,_cpu_class
|
|
jne 3f
|
|
#endif
|
|
/*
|
|
* We have to check each PTE for user write permission.
|
|
* The checking may cause a page fault, so it is important to set
|
|
* up everything for return via copyout_fault before here.
|
|
*/
|
|
/* compute number of pages */
|
|
movl %edi,%ecx
|
|
andl $NBPG-1,%ecx
|
|
addl %ebx,%ecx
|
|
decl %ecx
|
|
shrl $IDXSHIFT+2,%ecx
|
|
incl %ecx
|
|
|
|
/* compute PTE offset for start address */
|
|
movl %edi,%edx
|
|
shrl $IDXSHIFT,%edx
|
|
andb $0xfc,%dl
|
|
|
|
1: /* check PTE for each page */
|
|
movb _PTmap(%edx),%al
|
|
andb $0x07,%al /* Pages must be VALID + USERACC + WRITABLE */
|
|
cmpb $0x07,%al
|
|
je 2f
|
|
|
|
/* simulate a trap */
|
|
pushl %edx
|
|
pushl %ecx
|
|
shll $IDXSHIFT,%edx
|
|
pushl %edx
|
|
call _trapwrite /* trapwrite(addr) */
|
|
popl %edx
|
|
popl %ecx
|
|
popl %edx
|
|
|
|
orl %eax,%eax /* if not ok, return EFAULT */
|
|
jnz copyout_fault
|
|
|
|
2:
|
|
addl $4,%edx
|
|
decl %ecx
|
|
jnz 1b /* check next page */
|
|
#endif /* I386_CPU */
|
|
|
|
/* bcopy(%esi, %edi, %ebx) */
|
|
3:
|
|
movl %ebx,%ecx
|
|
shrl $2,%ecx
|
|
cld
|
|
rep
|
|
movsl
|
|
movb %bl,%cl
|
|
andb $3,%cl
|
|
rep
|
|
movsb
|
|
|
|
done_copyout:
|
|
popl %ebx
|
|
popl %edi
|
|
popl %esi
|
|
xorl %eax,%eax
|
|
movl _curpcb,%edx
|
|
movl %eax,PCB_ONFAULT(%edx)
|
|
ret
|
|
|
|
ALIGN_TEXT
|
|
copyout_fault:
|
|
popl %ebx
|
|
popl %edi
|
|
popl %esi
|
|
movl _curpcb,%edx
|
|
movl $0,PCB_ONFAULT(%edx)
|
|
movl $EFAULT,%eax
|
|
ret
|
|
|
|
/* copyin(from_user, to_kernel, len) */
|
|
ENTRY(copyin)
|
|
movl _curpcb,%eax
|
|
movl $copyin_fault,PCB_ONFAULT(%eax)
|
|
pushl %esi
|
|
pushl %edi
|
|
movl 12(%esp),%esi /* caddr_t from */
|
|
movl 16(%esp),%edi /* caddr_t to */
|
|
movl 20(%esp),%ecx /* size_t len */
|
|
|
|
/*
|
|
* make sure address is valid
|
|
*/
|
|
movl %esi,%edx
|
|
addl %ecx,%edx
|
|
jc copyin_fault
|
|
cmpl $VM_MAXUSER_ADDRESS,%edx
|
|
ja copyin_fault
|
|
|
|
movb %cl,%al
|
|
shrl $2,%ecx /* copy longword-wise */
|
|
cld
|
|
rep
|
|
movsl
|
|
movb %al,%cl
|
|
andb $3,%cl /* copy remaining bytes */
|
|
rep
|
|
movsb
|
|
|
|
popl %edi
|
|
popl %esi
|
|
xorl %eax,%eax
|
|
movl _curpcb,%edx
|
|
movl %eax,PCB_ONFAULT(%edx)
|
|
ret
|
|
|
|
ALIGN_TEXT
|
|
copyin_fault:
|
|
popl %edi
|
|
popl %esi
|
|
movl _curpcb,%edx
|
|
movl $0,PCB_ONFAULT(%edx)
|
|
movl $EFAULT,%eax
|
|
ret
|
|
|
|
/*
|
|
* fu{byte,sword,word} : fetch a byte (sword, word) from user memory
|
|
*/
|
|
ALTENTRY(fuiword)
|
|
ENTRY(fuword)
|
|
movl _curpcb,%ecx
|
|
movl $fusufault,PCB_ONFAULT(%ecx)
|
|
movl 4(%esp),%edx /* from */
|
|
|
|
cmpl $VM_MAXUSER_ADDRESS-4,%edx /* verify address is valid */
|
|
ja fusufault
|
|
|
|
movl (%edx),%eax
|
|
movl $0,PCB_ONFAULT(%ecx)
|
|
ret
|
|
|
|
/*
|
|
* These two routines are called from the profiling code, potentially
|
|
* at interrupt time. If they fail, that's okay, good things will
|
|
* happen later. Fail all the time for now - until the trap code is
|
|
* able to deal with this.
|
|
*/
|
|
ALTENTRY(suswintr)
|
|
ENTRY(fuswintr)
|
|
movl $-1,%eax
|
|
ret
|
|
|
|
ENTRY(fusword)
|
|
movl _curpcb,%ecx
|
|
movl $fusufault,PCB_ONFAULT(%ecx)
|
|
movl 4(%esp),%edx
|
|
|
|
cmpl $VM_MAXUSER_ADDRESS-2,%edx
|
|
ja fusufault
|
|
|
|
movzwl (%edx),%eax
|
|
movl $0,PCB_ONFAULT(%ecx)
|
|
ret
|
|
|
|
ALTENTRY(fuibyte)
|
|
ENTRY(fubyte)
|
|
movl _curpcb,%ecx
|
|
movl $fusufault,PCB_ONFAULT(%ecx)
|
|
movl 4(%esp),%edx
|
|
|
|
cmpl $VM_MAXUSER_ADDRESS-1,%edx
|
|
ja fusufault
|
|
|
|
movzbl (%edx),%eax
|
|
movl $0,PCB_ONFAULT(%ecx)
|
|
ret
|
|
|
|
ALIGN_TEXT
|
|
fusufault:
|
|
movl _curpcb,%ecx
|
|
xorl %eax,%eax
|
|
movl %eax,PCB_ONFAULT(%ecx)
|
|
decl %eax
|
|
ret
|
|
|
|
/*
|
|
* su{byte,sword,word}: write a byte (word, longword) to user memory
|
|
*/
|
|
ALTENTRY(suiword)
|
|
ENTRY(suword)
|
|
movl _curpcb,%ecx
|
|
movl $fusufault,PCB_ONFAULT(%ecx)
|
|
movl 4(%esp),%edx
|
|
|
|
#if defined(I386_CPU)
|
|
|
|
#if defined(I486_CPU) || defined(I586_CPU)
|
|
cmpl $CPUCLASS_386,_cpu_class
|
|
jne 2f /* we only have to set the right segment selector */
|
|
#endif /* I486_CPU || I586_CPU */
|
|
|
|
/* XXX - page boundary crossing is still not handled */
|
|
movl %edx,%eax
|
|
shrl $IDXSHIFT,%edx
|
|
andb $0xfc,%dl
|
|
movb _PTmap(%edx),%dl
|
|
andb $0x7,%dl /* must be VALID + USERACC + WRITE */
|
|
cmpb $0x7,%dl
|
|
je 1f
|
|
|
|
/* simulate a trap */
|
|
pushl %eax
|
|
call _trapwrite
|
|
popl %edx /* remove junk parameter from stack */
|
|
movl _curpcb,%ecx /* restore trashed register */
|
|
orl %eax,%eax
|
|
jnz fusufault
|
|
1:
|
|
movl 4(%esp),%edx
|
|
#endif
|
|
|
|
2:
|
|
cmpl $VM_MAXUSER_ADDRESS-4,%edx /* verify address validity */
|
|
ja fusufault
|
|
|
|
movl 8(%esp),%eax
|
|
movl %eax,(%edx)
|
|
xorl %eax,%eax
|
|
movl %eax,PCB_ONFAULT(%ecx)
|
|
ret
|
|
|
|
ENTRY(susword)
|
|
movl _curpcb,%ecx
|
|
movl $fusufault,PCB_ONFAULT(%ecx)
|
|
movl 4(%esp),%edx
|
|
|
|
#if defined(I386_CPU)
|
|
|
|
#if defined(I486_CPU) || defined(I586_CPU)
|
|
cmpl $CPUCLASS_386,_cpu_class
|
|
jne 2f
|
|
#endif /* I486_CPU || I586_CPU */
|
|
|
|
/* XXX - page boundary crossing is still not handled */
|
|
movl %edx,%eax
|
|
shrl $IDXSHIFT,%edx
|
|
andb $0xfc,%dl
|
|
movb _PTmap(%edx),%dl
|
|
andb $0x7,%dl /* must be VALID + USERACC + WRITE */
|
|
cmpb $0x7,%dl
|
|
je 1f
|
|
|
|
/* simulate a trap */
|
|
pushl %eax
|
|
call _trapwrite
|
|
popl %edx /* remove junk parameter from stack */
|
|
movl _curpcb,%ecx /* restore trashed register */
|
|
orl %eax,%eax
|
|
jnz fusufault
|
|
1:
|
|
movl 4(%esp),%edx
|
|
#endif
|
|
|
|
2:
|
|
cmpl $VM_MAXUSER_ADDRESS-2,%edx /* verify address validity */
|
|
ja fusufault
|
|
|
|
movw 8(%esp),%ax
|
|
movw %ax,(%edx)
|
|
xorl %eax,%eax
|
|
movl %eax,PCB_ONFAULT(%ecx)
|
|
ret
|
|
|
|
ALTENTRY(suibyte)
|
|
ENTRY(subyte)
|
|
movl _curpcb,%ecx
|
|
movl $fusufault,PCB_ONFAULT(%ecx)
|
|
movl 4(%esp),%edx
|
|
|
|
#if defined(I386_CPU)
|
|
|
|
#if defined(I486_CPU) || defined(I586_CPU)
|
|
cmpl $CPUCLASS_386,_cpu_class
|
|
jne 2f
|
|
#endif /* I486_CPU || I586_CPU */
|
|
|
|
movl %edx,%eax
|
|
shrl $IDXSHIFT,%edx
|
|
andb $0xfc,%dl
|
|
movb _PTmap(%edx),%dl
|
|
andb $0x7,%dl /* must be VALID + USERACC + WRITE */
|
|
cmpb $0x7,%dl
|
|
je 1f
|
|
|
|
/* simulate a trap */
|
|
pushl %eax
|
|
call _trapwrite
|
|
popl %edx /* remove junk parameter from stack */
|
|
movl _curpcb,%ecx /* restore trashed register */
|
|
orl %eax,%eax
|
|
jnz fusufault
|
|
1:
|
|
movl 4(%esp),%edx
|
|
#endif
|
|
|
|
2:
|
|
cmpl $VM_MAXUSER_ADDRESS-1,%edx /* verify address validity */
|
|
ja fusufault
|
|
|
|
movb 8(%esp),%al
|
|
movb %al,(%edx)
|
|
xorl %eax,%eax
|
|
movl %eax,PCB_ONFAULT(%ecx)
|
|
ret
|
|
|
|
/*
|
|
* copyoutstr(from, to, maxlen, int *lencopied)
|
|
* copy a string from from to to, stop when a 0 character is reached.
|
|
* return ENAMETOOLONG if string is longer than maxlen, and
|
|
* EFAULT on protection violations. If lencopied is non-zero,
|
|
* return the actual length in *lencopied.
|
|
*/
|
|
ENTRY(copyoutstr)
|
|
pushl %esi
|
|
pushl %edi
|
|
movl _curpcb,%ecx
|
|
movl $cpystrflt,PCB_ONFAULT(%ecx) /* XXX rename copyoutstr_fault */
|
|
|
|
movl 12(%esp),%esi /* %esi = from */
|
|
movl 16(%esp),%edi /* %edi = to */
|
|
movl 20(%esp),%edx /* %edx = maxlen */
|
|
cld
|
|
|
|
#if defined(I386_CPU)
|
|
|
|
#if defined(I486_CPU) || defined(I586_CPU)
|
|
cmpl $CPUCLASS_386,_cpu_class
|
|
jne 5f
|
|
#endif /* I486_CPU || I586_CPU */
|
|
|
|
1:
|
|
/*
|
|
* It suffices to check that the first byte is in user space, because
|
|
* we look at a page at a time and the end address is on a page
|
|
* boundary.
|
|
*/
|
|
cmpl $VM_MAXUSER_ADDRESS-1,%edi
|
|
ja cpystrflt
|
|
|
|
movl %edi,%eax
|
|
shrl $IDXSHIFT,%eax
|
|
andb $0xfc,%al
|
|
movb _PTmap(%eax),%al
|
|
andb $7,%al
|
|
cmpb $7,%al
|
|
je 2f
|
|
|
|
/* simulate trap */
|
|
pushl %edx
|
|
pushl %edi
|
|
call _trapwrite
|
|
cld
|
|
popl %edi
|
|
popl %edx
|
|
orl %eax,%eax
|
|
jnz cpystrflt
|
|
|
|
2: /* copy up to end of this page */
|
|
movl %edi,%eax
|
|
andl $NBPG-1,%eax
|
|
movl $NBPG,%ecx
|
|
subl %eax,%ecx /* ecx = NBPG - (src % NBPG) */
|
|
cmpl %ecx,%edx
|
|
jae 3f
|
|
movl %edx,%ecx /* ecx = min(ecx, edx) */
|
|
3:
|
|
orl %ecx,%ecx
|
|
jz 4f
|
|
decl %ecx
|
|
decl %edx
|
|
lodsb
|
|
stosb
|
|
orb %al,%al
|
|
jnz 3b
|
|
|
|
/* Success -- 0 byte reached */
|
|
decl %edx
|
|
xorl %eax,%eax
|
|
jmp 6f
|
|
|
|
4: /* next page */
|
|
orl %edx,%edx
|
|
jnz 1b
|
|
|
|
/* edx is zero -- return ENAMETOOLONG */
|
|
movl $ENAMETOOLONG,%eax
|
|
jmp cpystrflt_x
|
|
#endif /* I386_CPU */
|
|
|
|
#if defined(I486_CPU) || defined(I586_CPU)
|
|
5:
|
|
incl %edx
|
|
1:
|
|
decl %edx
|
|
jz 2f
|
|
/*
|
|
* XXX - would be faster to rewrite this function to use
|
|
* strlen() and copyout().
|
|
*/
|
|
cmpl $VM_MAXUSER_ADDRESS-1,%edi
|
|
ja cpystrflt
|
|
|
|
lodsb
|
|
stosb
|
|
orb %al,%al
|
|
jnz 1b
|
|
|
|
/* Success -- 0 byte reached */
|
|
decl %edx
|
|
xorl %eax,%eax
|
|
jmp cpystrflt_x
|
|
2:
|
|
/* edx is zero -- return ENAMETOOLONG */
|
|
movl $ENAMETOOLONG,%eax
|
|
jmp cpystrflt_x
|
|
|
|
#endif /* I486_CPU || I586_CPU */
|
|
|
|
|
|
/*
|
|
* copyinstr(from, to, maxlen, int *lencopied)
|
|
* copy a string from from to to, stop when a 0 character is reached.
|
|
* return ENAMETOOLONG if string is longer than maxlen, and
|
|
* EFAULT on protection violations. If lencopied is non-zero,
|
|
* return the actual length in *lencopied.
|
|
*/
|
|
ENTRY(copyinstr)
|
|
pushl %esi
|
|
pushl %edi
|
|
movl _curpcb,%ecx
|
|
movl $cpystrflt,PCB_ONFAULT(%ecx)
|
|
|
|
movl 12(%esp),%esi /* %esi = from */
|
|
movl 16(%esp),%edi /* %edi = to */
|
|
movl 20(%esp),%edx /* %edx = maxlen */
|
|
|
|
movl $VM_MAXUSER_ADDRESS,%eax
|
|
|
|
/* make sure 'from' is within bounds */
|
|
subl %esi,%eax
|
|
jbe cpystrflt
|
|
|
|
/* restrict maxlen to <= VM_MAXUSER_ADDRESS-from */
|
|
cmpl %edx,%eax
|
|
jae 1f
|
|
movl %eax,%edx
|
|
movl %eax,20(%esp)
|
|
1:
|
|
incl %edx
|
|
cld
|
|
|
|
2:
|
|
decl %edx
|
|
jz 3f
|
|
|
|
lodsb
|
|
stosb
|
|
orb %al,%al
|
|
jnz 2b
|
|
|
|
/* Success -- 0 byte reached */
|
|
decl %edx
|
|
xorl %eax,%eax
|
|
jmp cpystrflt_x
|
|
3:
|
|
/* edx is zero - return ENAMETOOLONG or EFAULT */
|
|
cmpl $VM_MAXUSER_ADDRESS,%esi
|
|
jae cpystrflt
|
|
4:
|
|
movl $ENAMETOOLONG,%eax
|
|
jmp cpystrflt_x
|
|
|
|
cpystrflt:
|
|
movl $EFAULT,%eax
|
|
|
|
cpystrflt_x:
|
|
/* set *lencopied and return %eax */
|
|
movl _curpcb,%ecx
|
|
movl $0,PCB_ONFAULT(%ecx)
|
|
movl 20(%esp),%ecx
|
|
subl %edx,%ecx
|
|
movl 24(%esp),%edx
|
|
testl %edx,%edx
|
|
jz 1f
|
|
movl %ecx,(%edx)
|
|
1:
|
|
popl %edi
|
|
popl %esi
|
|
ret
|
|
|
|
|
|
/*
|
|
* copystr(from, to, maxlen, int *lencopied)
|
|
*/
|
|
ENTRY(copystr)
|
|
pushl %esi
|
|
pushl %edi
|
|
|
|
movl 12(%esp),%esi /* %esi = from */
|
|
movl 16(%esp),%edi /* %edi = to */
|
|
movl 20(%esp),%edx /* %edx = maxlen */
|
|
incl %edx
|
|
cld
|
|
1:
|
|
decl %edx
|
|
jz 4f
|
|
lodsb
|
|
stosb
|
|
orb %al,%al
|
|
jnz 1b
|
|
|
|
/* Success -- 0 byte reached */
|
|
decl %edx
|
|
xorl %eax,%eax
|
|
jmp 6f
|
|
4:
|
|
/* edx is zero -- return ENAMETOOLONG */
|
|
movl $ENAMETOOLONG,%eax
|
|
|
|
6:
|
|
/* set *lencopied and return %eax */
|
|
movl 20(%esp),%ecx
|
|
subl %edx,%ecx
|
|
movl 24(%esp),%edx
|
|
orl %edx,%edx
|
|
jz 7f
|
|
movl %ecx,(%edx)
|
|
7:
|
|
popl %edi
|
|
popl %esi
|
|
ret
|
|
|
|
/*
|
|
* Miscellaneous kernel support functions
|
|
*/
|
|
ENTRY(ffs)
|
|
bsfl 4(%esp),%eax
|
|
jz 1f
|
|
incl %eax
|
|
ret
|
|
1:
|
|
xorl %eax,%eax
|
|
ret
|
|
|
|
ENTRY(bcmp)
|
|
pushl %edi
|
|
pushl %esi
|
|
movl 12(%esp),%edi
|
|
movl 16(%esp),%esi
|
|
movl 20(%esp),%edx
|
|
xorl %eax,%eax
|
|
|
|
movl %edx,%ecx
|
|
shrl $2,%ecx
|
|
cld /* compare forwards */
|
|
repe
|
|
cmpsl
|
|
jne 1f
|
|
|
|
movl %edx,%ecx
|
|
andl $3,%ecx
|
|
repe
|
|
cmpsb
|
|
je 2f
|
|
1:
|
|
incl %eax
|
|
2:
|
|
popl %esi
|
|
popl %edi
|
|
ret
|
|
|
|
|
|
/*
|
|
* Handling of special 386 registers and descriptor tables etc
|
|
*/
|
|
/* void lgdt(struct region_descriptor *rdp); */
|
|
ENTRY(lgdt)
|
|
/* reload the descriptor table */
|
|
movl 4(%esp),%eax
|
|
lgdt (%eax)
|
|
|
|
/* flush the prefetch q */
|
|
jmp 1f
|
|
nop
|
|
1:
|
|
/* reload "stale" selectors */
|
|
movl $KDSEL,%eax
|
|
movl %ax,%ds
|
|
movl %ax,%es
|
|
movl %ax,%ss
|
|
|
|
/* reload code selector by turning return into intersegmental return */
|
|
movl (%esp),%eax
|
|
pushl %eax
|
|
# movl $KCSEL,4(%esp)
|
|
movl $8,4(%esp)
|
|
lret
|
|
|
|
/*
|
|
* void lidt(struct region_descriptor *rdp);
|
|
*/
|
|
ENTRY(lidt)
|
|
movl 4(%esp),%eax
|
|
lidt (%eax)
|
|
ret
|
|
|
|
/*
|
|
* void lldt(u_short sel)
|
|
*/
|
|
ENTRY(lldt)
|
|
lldt 4(%esp)
|
|
ret
|
|
|
|
/*
|
|
* void ltr(u_short sel)
|
|
*/
|
|
ENTRY(ltr)
|
|
ltr 4(%esp)
|
|
ret
|
|
|
|
/* ssdtosd(*ssdp,*sdp) */
|
|
ENTRY(ssdtosd)
|
|
pushl %ebx
|
|
movl 8(%esp),%ecx
|
|
movl 8(%ecx),%ebx
|
|
shll $16,%ebx
|
|
movl (%ecx),%edx
|
|
roll $16,%edx
|
|
movb %dh,%bl
|
|
movb %dl,%bh
|
|
rorl $8,%ebx
|
|
movl 4(%ecx),%eax
|
|
movw %ax,%dx
|
|
andl $0xf0000,%eax
|
|
orl %eax,%ebx
|
|
movl 12(%esp),%ecx
|
|
movl %edx,(%ecx)
|
|
movl %ebx,4(%ecx)
|
|
popl %ebx
|
|
ret
|
|
|
|
/* load_cr0(cr0) */
|
|
ENTRY(load_cr0)
|
|
movl 4(%esp),%eax
|
|
movl %eax,%cr0
|
|
ret
|
|
|
|
/* rcr0() */
|
|
ENTRY(rcr0)
|
|
movl %cr0,%eax
|
|
ret
|
|
|
|
/* rcr3() */
|
|
ENTRY(rcr3)
|
|
movl %cr3,%eax
|
|
ret
|
|
|
|
/* void load_cr3(caddr_t cr3) */
|
|
ENTRY(load_cr3)
|
|
movl 4(%esp),%eax
|
|
movl %eax,%cr3
|
|
ret
|
|
|
|
|
|
/*****************************************************************************/
|
|
/* setjump, longjump */
|
|
/*****************************************************************************/
|
|
|
|
ENTRY(setjmp)
|
|
movl 4(%esp),%eax
|
|
movl %ebx,(%eax) /* save ebx */
|
|
movl %esp,4(%eax) /* save esp */
|
|
movl %ebp,8(%eax) /* save ebp */
|
|
movl %esi,12(%eax) /* save esi */
|
|
movl %edi,16(%eax) /* save edi */
|
|
movl (%esp),%edx /* get rta */
|
|
movl %edx,20(%eax) /* save eip */
|
|
xorl %eax,%eax /* return(0); */
|
|
ret
|
|
|
|
ENTRY(longjmp)
|
|
movl 4(%esp),%eax
|
|
movl (%eax),%ebx /* restore ebx */
|
|
movl 4(%eax),%esp /* restore esp */
|
|
movl 8(%eax),%ebp /* restore ebp */
|
|
movl 12(%eax),%esi /* restore esi */
|
|
movl 16(%eax),%edi /* restore edi */
|
|
movl 20(%eax),%edx /* get rta */
|
|
movl %edx,(%esp) /* put in return frame */
|
|
xorl %eax,%eax /* return(1); */
|
|
incl %eax
|
|
ret
|