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/*-
* Copyright (c) 2003 Peter Wemm.
* 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.
* 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.
*
* $FreeBSD$
*/
#include "opt_ddb.h"
#include <machine/asmacros.h>
#include <machine/intr_machdep.h>
#include <machine/pmap.h>
#include "assym.s"
ALIGN_DATA
.globl intrcnt, eintrcnt
intrcnt:
.space INTRCNT_COUNT * 8
eintrcnt:
.globl intrnames, eintrnames
intrnames:
.space INTRCNT_COUNT * (MAXCOMLEN + 1)
eintrnames:
.text
/*
* bcopy family
* void bzero(void *buf, u_int len)
*/
/* done */
ENTRY(bzero)
movq %rsi,%rcx
xorq %rax,%rax
shrq $3,%rcx
cld
rep
stosq
movq %rsi,%rcx
andq $7,%rcx
rep
stosb
ret
/* Address: %rdi */
ENTRY(pagezero)
movq $-PAGE_SIZE,%rdx
subq %rdx,%rdi
xorq %rax,%rax
1:
movnti %rax,(%rdi,%rdx)
movnti %rax,8(%rdi,%rdx)
movnti %rax,16(%rdi,%rdx)
movnti %rax,24(%rdi,%rdx)
addq $32,%rdx
jne 1b
sfence
ret
ENTRY(bcmp)
xorq %rax,%rax
movq %rdx,%rcx
shrq $3,%rcx
cld /* compare forwards */
repe
cmpsq
jne 1f
movq %rdx,%rcx
andq $7,%rcx
repe
cmpsb
je 2f
1:
incq %rax
2:
ret
/*
* bcopy(src, dst, cnt)
* rdi, rsi, rdx
* ws@tools.de (Wolfgang Solfrank, TooLs GmbH) +49-228-985800
*/
ENTRY(bcopy)
xchgq %rsi,%rdi
movq %rdx,%rcx
movq %rdi,%rax
subq %rsi,%rax
cmpq %rcx,%rax /* overlapping && src < dst? */
jb 1f
shrq $3,%rcx /* copy by 64-bit words */
cld /* nope, copy forwards */
rep
movsq
movq %rdx,%rcx
andq $7,%rcx /* any bytes left? */
rep
movsb
ret
/* ALIGN_TEXT */
1:
addq %rcx,%rdi /* copy backwards */
addq %rcx,%rsi
decq %rdi
decq %rsi
andq $7,%rcx /* any fractional bytes? */
std
rep
movsb
movq %rdx,%rcx /* copy remainder by 32-bit words */
shrq $3,%rcx
subq $7,%rsi
subq $7,%rdi
rep
movsq
cld
ret
/*
* Note: memcpy does not support overlapping copies
*/
ENTRY(memcpy)
movq %rdx,%rcx
shrq $3,%rcx /* copy by 64-bit words */
cld /* copy forwards */
rep
movsq
movq %rdx,%rcx
andq $7,%rcx /* any bytes left? */
rep
movsb
ret
/*
* pagecopy(%rdi=from, %rsi=to)
*/
ENTRY(pagecopy)
movq $-PAGE_SIZE,%rax
movq %rax,%rdx
subq %rax,%rdi
subq %rax,%rsi
1:
prefetchnta (%rdi,%rax)
addq $64,%rax
jne 1b
2:
movq (%rdi,%rdx),%rax
movnti %rax,(%rsi,%rdx)
movq 8(%rdi,%rdx),%rax
movnti %rax,8(%rsi,%rdx)
movq 16(%rdi,%rdx),%rax
movnti %rax,16(%rsi,%rdx)
movq 24(%rdi,%rdx),%rax
movnti %rax,24(%rsi,%rdx)
addq $32,%rdx
jne 2b
sfence
ret
/* fillw(pat, base, cnt) */
/* %rdi,%rsi, %rdx */
ENTRY(fillw)
movq %rdi,%rax
movq %rsi,%rdi
movq %rdx,%rcx
cld
rep
stosw
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.
*/
/*
* copyout(from_kernel, to_user, len) - MP SAFE
* %rdi, %rsi, %rdx
*/
ENTRY(copyout)
movq PCPU(CURPCB),%rax
movq $copyout_fault,PCB_ONFAULT(%rax)
testq %rdx,%rdx /* 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.
*/
/*
* First, prevent address wrapping.
*/
movq %rsi,%rax
addq %rdx,%rax
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.
*/
movq $VM_MAXUSER_ADDRESS,%rcx
cmpq %rcx,%rax
ja copyout_fault
xchgq %rdi, %rsi
/* bcopy(%rsi, %rdi, %rdx) */
movq %rdx,%rcx
shrq $3,%rcx
cld
rep
movsq
movb %dl,%cl
andb $7,%cl
rep
movsb
done_copyout:
xorq %rax,%rax
movq PCPU(CURPCB),%rdx
movq %rax,PCB_ONFAULT(%rdx)
ret
ALIGN_TEXT
copyout_fault:
movq PCPU(CURPCB),%rdx
movq $0,PCB_ONFAULT(%rdx)
movq $EFAULT,%rax
ret
/*
* copyin(from_user, to_kernel, len) - MP SAFE
* %rdi, %rsi, %rdx
*/
ENTRY(copyin)
movq PCPU(CURPCB),%rax
movq $copyin_fault,PCB_ONFAULT(%rax)
testq %rdx,%rdx /* anything to do? */
jz done_copyin
/*
* make sure address is valid
*/
movq %rdi,%rax
addq %rdx,%rax
jc copyin_fault
movq $VM_MAXUSER_ADDRESS,%rcx
cmpq %rcx,%rax
ja copyin_fault
xchgq %rdi, %rsi
movq %rdx, %rcx
movb %cl,%al
shrq $3,%rcx /* copy longword-wise */
cld
rep
movsq
movb %al,%cl
andb $7,%cl /* copy remaining bytes */
rep
movsb
done_copyin:
xorq %rax,%rax
movq PCPU(CURPCB),%rdx
movq %rax,PCB_ONFAULT(%rdx)
ret
ALIGN_TEXT
copyin_fault:
movq PCPU(CURPCB),%rdx
movq $0,PCB_ONFAULT(%rdx)
movq $EFAULT,%rax
ret
/*
* casuptr. Compare and set user pointer. Returns -1 or the current value.
* dst = %rdi, old = %rsi, new = %rdx
*/
ENTRY(casuptr)
movq PCPU(CURPCB),%rcx
movq $fusufault,PCB_ONFAULT(%rcx)
movq $VM_MAXUSER_ADDRESS-4,%rax
cmpq %rax,%rdi /* verify address is valid */
ja fusufault
movq %rsi, %rax /* old */
#ifdef SMP
lock
#endif
cmpxchgq %rdx, (%rdi) /* new = %rdx */
/*
* The old value is in %eax. If the store succeeded it will be the
* value we expected (old) from before the store, otherwise it will
* be the current value.
*/
movq PCPU(CURPCB),%rcx
movq $fusufault,PCB_ONFAULT(%rcx)
movq $0,PCB_ONFAULT(%rcx)
ret
/*
* Fetch (load) a 64-bit word, a 32-bit word, a 16-bit word, or an 8-bit
* byte from user memory. All these functions are MPSAFE.
* addr = %rdi
*/
ALTENTRY(fuword64)
ENTRY(fuword)
movq PCPU(CURPCB),%rcx
movq $fusufault,PCB_ONFAULT(%rcx)
movq $VM_MAXUSER_ADDRESS-8,%rax
cmpq %rax,%rdi /* verify address is valid */
ja fusufault
movq (%rdi),%rax
movq $0,PCB_ONFAULT(%rcx)
ret
ENTRY(fuword32)
movq PCPU(CURPCB),%rcx
movq $fusufault,PCB_ONFAULT(%rcx)
movq $VM_MAXUSER_ADDRESS-4,%rax
cmpq %rax,%rdi /* verify address is valid */
ja fusufault
movl (%rdi),%eax
movq $0,PCB_ONFAULT(%rcx)
ret
/*
* fuswintr() and suswintr() are specialized variants of fuword16() and
* suword16(), respectively. They are called from the profiling code,
* potentially at interrupt time. If they fail, that's okay; good things
* will happen later. They always fail for now, until the trap code is
* able to deal with this.
*/
ALTENTRY(suswintr)
ENTRY(fuswintr)
movq $-1,%rax
ret
ENTRY(fuword16)
movq PCPU(CURPCB),%rcx
movq $fusufault,PCB_ONFAULT(%rcx)
movq $VM_MAXUSER_ADDRESS-2,%rax
cmpq %rax,%rdi
ja fusufault
movzwl (%rdi),%eax
movq $0,PCB_ONFAULT(%rcx)
ret
ENTRY(fubyte)
movq PCPU(CURPCB),%rcx
movq $fusufault,PCB_ONFAULT(%rcx)
movq $VM_MAXUSER_ADDRESS-1,%rax
cmpq %rax,%rdi
ja fusufault
movzbl (%rdi),%eax
movq $0,PCB_ONFAULT(%rcx)
ret
ALIGN_TEXT
fusufault:
movq PCPU(CURPCB),%rcx
xorq %rax,%rax
movq %rax,PCB_ONFAULT(%rcx)
decq %rax
ret
/*
* Store a 64-bit word, a 32-bit word, a 16-bit word, or an 8-bit byte to
* user memory. All these functions are MPSAFE.
* addr = %rdi, value = %rsi
*/
ALTENTRY(suword64)
ENTRY(suword)
movq PCPU(CURPCB),%rcx
movq $fusufault,PCB_ONFAULT(%rcx)
movq $VM_MAXUSER_ADDRESS-8,%rax
cmpq %rax,%rdi /* verify address validity */
ja fusufault
movq %rsi,(%rdi)
xorq %rax,%rax
movq PCPU(CURPCB),%rcx
movq %rax,PCB_ONFAULT(%rcx)
ret
ENTRY(suword32)
movq PCPU(CURPCB),%rcx
movq $fusufault,PCB_ONFAULT(%rcx)
movq $VM_MAXUSER_ADDRESS-4,%rax
cmpq %rax,%rdi /* verify address validity */
ja fusufault
movl %esi,(%rdi)
xorq %rax,%rax
movq PCPU(CURPCB),%rcx
movq %rax,PCB_ONFAULT(%rcx)
ret
ENTRY(suword16)
movq PCPU(CURPCB),%rcx
movq $fusufault,PCB_ONFAULT(%rcx)
movq $VM_MAXUSER_ADDRESS-2,%rax
cmpq %rax,%rdi /* verify address validity */
ja fusufault
movw %si,(%rdi)
xorq %rax,%rax
movq PCPU(CURPCB),%rcx /* restore trashed register */
movq %rax,PCB_ONFAULT(%rcx)
ret
ENTRY(subyte)
movq PCPU(CURPCB),%rcx
movq $fusufault,PCB_ONFAULT(%rcx)
movq $VM_MAXUSER_ADDRESS-1,%rax
cmpq %rax,%rdi /* verify address validity */
ja fusufault
movl %esi, %eax
movb %al,(%rdi)
xorq %rax,%rax
movq PCPU(CURPCB),%rcx /* restore trashed register */
movq %rax,PCB_ONFAULT(%rcx)
ret
/*
* copyinstr(from, to, maxlen, int *lencopied) - MP SAFE
* %rdi, %rsi, %rdx, %rcx
*
* 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)
movq %rdx, %r8 /* %r8 = maxlen */
movq %rcx, %r9 /* %r9 = *len */
xchgq %rdi, %rsi /* %rdi = from, %rsi = to */
movq PCPU(CURPCB),%rcx
movq $cpystrflt,PCB_ONFAULT(%rcx)
movq $VM_MAXUSER_ADDRESS,%rax
/* make sure 'from' is within bounds */
subq %rsi,%rax
jbe cpystrflt
/* restrict maxlen to <= VM_MAXUSER_ADDRESS-from */
cmpq %rdx,%rax
jae 1f
movq %rax,%rdx
movq %rax,%r8
1:
incq %rdx
cld
2:
decq %rdx
jz 3f
lodsb
stosb
orb %al,%al
jnz 2b
/* Success -- 0 byte reached */
decq %rdx
xorq %rax,%rax
jmp cpystrflt_x
3:
/* rdx is zero - return ENAMETOOLONG or EFAULT */
movq $VM_MAXUSER_ADDRESS,%rax
cmpq %rax,%rsi
jae cpystrflt
4:
movq $ENAMETOOLONG,%rax
jmp cpystrflt_x
cpystrflt:
movq $EFAULT,%rax
cpystrflt_x:
/* set *lencopied and return %eax */
movq PCPU(CURPCB),%rcx
movq $0,PCB_ONFAULT(%rcx)
testq %r9,%r9
jz 1f
subq %rdx,%r8
movq %r8,(%r9)
1:
ret
/*
* copystr(from, to, maxlen, int *lencopied) - MP SAFE
* %rdi, %rsi, %rdx, %rcx
*/
ENTRY(copystr)
movq %rdx, %r8 /* %r8 = maxlen */
xchgq %rdi, %rsi
incq %rdx
cld
1:
decq %rdx
jz 4f
lodsb
stosb
orb %al,%al
jnz 1b
/* Success -- 0 byte reached */
decq %rdx
xorq %rax,%rax
jmp 6f
4:
/* rdx is zero -- return ENAMETOOLONG */
movq $ENAMETOOLONG,%rax
6:
testq %rcx, %rcx
jz 7f
/* set *lencopied and return %rax */
subq %rdx, %r8
movq %r8, (%rcx)
7:
ret
/*
* Handling of special 386 registers and descriptor tables etc
* %rdi
*/
/* void lgdt(struct region_descriptor *rdp); */
ENTRY(lgdt)
/* reload the descriptor table */
lgdt (%rdi)
/* flush the prefetch q */
jmp 1f
nop
1:
movl $KDSEL, %eax
movl %eax,%ds
movl %eax,%es
movl %eax,%fs /* Beware, use wrmsr to set 64 bit base */
movl %eax,%gs
movl %eax,%ss
/* reload code selector by turning return into intersegmental return */
popq %rax
pushq $KCSEL
pushq %rax
MEXITCOUNT
lretq
/*****************************************************************************/
/* setjump, longjump */
/*****************************************************************************/
ENTRY(setjmp)
movq %rbx,0(%rdi) /* save rbx */
movq %rsp,8(%rdi) /* save rsp */
movq %rbp,16(%rdi) /* save rbp */
movq %r12,24(%rdi) /* save r12 */
movq %r13,32(%rdi) /* save r13 */
movq %r14,40(%rdi) /* save r14 */
movq %r15,48(%rdi) /* save r15 */
movq 0(%rsp),%rdx /* get rta */
movq %rdx,56(%rdi) /* save rip */
xorl %eax,%eax /* return(0); */
ret
ENTRY(longjmp)
movq 0(%rdi),%rbx /* restore rbx */
movq 8(%rdi),%rsp /* restore rsp */
movq 16(%rdi),%rbp /* restore rbp */
movq 24(%rdi),%r12 /* restore r12 */
movq 32(%rdi),%r13 /* restore r13 */
movq 40(%rdi),%r14 /* restore r14 */
movq 48(%rdi),%r15 /* restore r15 */
movq 56(%rdi),%rdx /* get rta */
movq %rdx,0(%rsp) /* put in return frame */
xorl %eax,%eax /* return(1); */
incl %eax
ret
/*
* Support for BB-profiling (gcc -a). The kernbb program will extract
* the data from the kernel.
*/
.data
ALIGN_DATA
.globl bbhead
bbhead:
.quad 0
.text
NON_GPROF_ENTRY(__bb_init_func)
movq $1,(%rdi)
movq bbhead,%rax
movq %rax,32(%rdi)
movq %rdi,bbhead
NON_GPROF_RET
|