NetBSD/sys/kern/exec_aout.c

214 lines
6.3 KiB
C

/*
* Copyright (c) 1993 Christopher G. Demetriou
* 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 Christopher G. Demetriou.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software withough specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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: exec_aout.c,v 1.1 1993/09/05 01:33:35 cgd Exp $
*/
#include "param.h"
#include "systm.h"
#include "filedesc.h"
#include "kernel.h"
#include "proc.h"
#include "mount.h"
#include "malloc.h"
#include "namei.h"
#include "vnode.h"
#include "file.h"
#include "exec.h"
#include "resourcevar.h"
#include "wait.h"
#include "machine/cpu.h"
#include "machine/reg.h"
#include "machine/exec.h"
#include "mman.h"
#include "vm/vm.h"
#include "vm/vm_param.h"
#include "vm/vm_map.h"
#include "vm/vm_kern.h"
#include "vm/vm_pager.h"
/*
* exec_aout_makecmds(): Check if it's an a.out-format executable.
*
* Given a proc pointer and an exec package pointer, see if the referent
* of the epp is in a.out format. First check 'standard' magic numbers for
* this architecture. If that fails, try a cpu-dependent hook.
*
* This function, in the former case, or the hook, in the latter, is
* responsible for creating a set of vmcmds which can be used to build
* the process's vm space and inserting them into the exec package.
*
* XXX: NMAGIC and OMAGIC are currently not supported.
*/
int
exec_aout_makecmds(p, epp)
struct proc *p;
struct exec_package *epp;
{
u_long midmag, magic;
u_short mid;
int error;
midmag = ntohl(epp->ep_execp->a_midmag);
mid = (midmag >> 16) & 0x3ff;
magic = midmag & 0xffff;
#ifdef EXEC_DEBUG
printf("exec_makecmds: a_midmag is %x, magic=%x mid=%x\n",
epp->ep_execp->a_midmag, magic, mid);
#endif
midmag = mid << 16 | magic;
switch (midmag) {
case (MID_MACHINE << 16) | ZMAGIC:
error = exec_aout_prep_zmagic(p, epp);
break;
case (MID_MACHINE << 16) | OMAGIC:
case (MID_MACHINE << 16) | NMAGIC:
default:
error = cpu_exec_aout_makecmds(p, epp);
}
if (error && epp->ep_vcp)
kill_vmcmd(&epp->ep_vcp);
bad:
#ifdef EXEC_DEBUG
printf("exec_makecmds returning with error = %d\n", error);
#endif
return error;
}
/*
* exec_aout_prep_zmagic(): Prepare a 'native' ZMAGIC binary's exec package
*
* First, set of the various offsets/lengths in the exec package.
* Note that the ep_ssize parameter must be set to be the current stack
* limit; this is adjusted in the body of execve() to yield the
* appropriate stack segment usage once the argument length is
* calculated.
*
* Then, mark the text image busy (so it can be demand paged) or error
* out if this is not possible. Finally, set up vmcmds for the
* text, data, bss, and stack segments.
*/
int
exec_aout_prep_zmagic(p, epp)
struct proc *p;
struct exec_package *epp;
{
struct exec *execp = epp->ep_execp;
struct exec_vmcmd *ccmdp;
epp->ep_taddr = USRTEXT;
epp->ep_tsize = execp->a_text;
epp->ep_daddr = epp->ep_taddr + execp->a_text;
epp->ep_dsize = execp->a_data + execp->a_bss;
epp->ep_maxsaddr = USRSTACK - MAXSSIZ;
epp->ep_minsaddr = USRSTACK;
epp->ep_ssize = p->p_rlimit[RLIMIT_STACK].rlim_cur;
epp->ep_entry = execp->a_entry;
/*
* check if vnode is in open for writing, because we want to
* demand-page out of it. if it is, don't do it, for various
* reasons
*/
if ((execp->a_text != 0 || execp->a_data != 0) &&
(epp->ep_vp->v_flag & VTEXT) == 0 && epp->ep_vp->v_writecount != 0) {
#ifdef DIAGNOSTIC
if (epp->ep_vp->v_flag & VTEXT)
panic("exec: a VTEXT vnode has writecount != 0\n");
#endif
epp->ep_vcp = NULL;
return ETXTBSY;
}
epp->ep_vp->v_flag |= VTEXT;
/* set up command for text segment */
epp->ep_vcp = new_vmcmd(vmcmd_map_pagedvn,
execp->a_text,
epp->ep_taddr,
epp->ep_vp,
0,
VM_PROT_READ | VM_PROT_EXECUTE);
ccmdp = epp->ep_vcp;
/* set up command for data segment */
ccmdp->ev_next = new_vmcmd(vmcmd_map_pagedvn,
execp->a_data,
epp->ep_daddr,
epp->ep_vp,
execp->a_text,
VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE);
ccmdp = ccmdp->ev_next;
/* set up command for bss segment */
ccmdp->ev_next = new_vmcmd(vmcmd_map_zero,
execp->a_bss,
epp->ep_daddr + execp->a_data,
0,
0,
VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE);
ccmdp = ccmdp->ev_next;
/*
* set up commands for stack. note that this takes *two*, one to
* map the part of the stack which we can access, and one to map
* the part which we can't.
*
* arguably, it could be made into one, but that would require the
* addition of another mapping proc, which is unnecessary
*
* note that in memory, things assumed to be: 0 ....... ep_maxsaddr
* <stack> ep_minsaddr
*/
ccmdp->ev_next = new_vmcmd(vmcmd_map_zero,
((epp->ep_minsaddr - epp->ep_ssize) - epp->ep_maxsaddr),
epp->ep_maxsaddr,
0,
0,
VM_PROT_NONE);
ccmdp = ccmdp->ev_next;
ccmdp->ev_next = new_vmcmd(vmcmd_map_zero,
epp->ep_ssize,
(epp->ep_minsaddr - epp->ep_ssize),
0,
0,
VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE);
return 0;
}