sys/platform/vkernel/i386/locore.s

   1 /*
   2  * Copyright (c) 2006 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/sys/platform/vkernel/i386/locore.s,v 1.6 2007/01/08 03:33:43 dillon Exp $
  35  */
  36
  37 #include <sys/syscall.h>
  38 #include <machine/asmacros.h>
  39 #include <machine/psl.h>
  40 #include "assym.s"
  41
  42         .globl  kernbase
  43         .set    kernbase,KERNBASE
  44
  45         /*
  46          * The sysinit and sysuninit sections have to be read-write data
  47          * sections, not read-only data sections.
  48          */
  49         .section        set_sysinit_set, "aw"
  50         .section        set_sysuninit_set, "aw"
  51
  52         .data
  53         ALIGN_DATA              /* just to be sure */
  54
  55         /*
  56          * Normally the startup code would begin here, but this is a
  57          * virtual kernel so we just have a main() in platform/init.c
  58          */
  59
  60         .text
  61
  62 /*
  63  * Signal trampoline, copied to top of user stack
  64  */
  65 NON_GPROF_ENTRY(sigcode)
  66         call    *SIGF_HANDLER(%esp)             /* call signal handler */
  67         lea     SIGF_UC(%esp),%eax              /* get ucontext_t */
  68         pushl   %eax
  69 #if 0
  70         testl   $PSL_VM,UC_EFLAGS(%eax)
  71         jne     9f
  72 #endif
  73 #if 0
  74 9:
  75 #endif
  76         movl    $SYS_sigreturn,%eax
  77         pushl   %eax                            /* junk to fake return addr. */
  78         int     $0x80                           /* enter kernel with args */
  79 0:      jmp     0b
  80
  81         ALIGN_TEXT
  82 esigcode:
  83
  84 /* void reset_dbregs() */
  85 ENTRY(reset_dbregs)
  86         movl    $0,%eax
  87         movl    %eax,%dr7     /* disable all breapoints first */
  88         movl    %eax,%dr0
  89         movl    %eax,%dr1
  90         movl    %eax,%dr2
  91         movl    %eax,%dr3
  92         movl    %eax,%dr6
  93         ret
  94
  95         .data
  96         .globl  szsigcode
  97 szsigcode:
  98         .long   esigcode - sigcode
  99