freebsd-nq/sys/i386/linux/imgact_linux.c
Søren Schmidt c21dee177f First incarnation of our Linux emulator or rather compatibility code.
This first shot only incorporaties so much functionality that DOOM
can run (the X version), signal handling is VERY weak, so is many
other things. But it meets my milestone number one (you guessed it
- running DOOM).

Uses /compat/linux as prefix for loading shared libs, so it won't
conflict with our own libs.

Kernel must be compiled with "options COMPAT_LINUX" for this to work.
1995-06-25 17:32:43 +00:00

236 lines
7.0 KiB
C

/*-
* Copyright (c) 1994-1995 Søren Schmidt
* All rights reserved.
*
* Based heavily on /sys/kern/imgact_aout.c which is:
* Copyright (c) 1993, David Greenman
*
* 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
* in this position and unchanged.
* 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. 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: imgact_linux.c,v 1.2 1995/06/07 21:27:57 sos Exp $
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/resourcevar.h>
#include <sys/exec.h>
#include <sys/mman.h>
#include <sys/imgact.h>
#include <sys/imgact_aout.h>
#include <sys/kernel.h>
#include <sys/sysent.h>
#include <vm/vm.h>
#include <vm/vm_kern.h>
int
exec_linux_imgact(iparams)
struct image_params *iparams;
{
struct exec *a_out = (struct exec *) iparams->image_header;
struct vmspace *vmspace = iparams->proc->p_vmspace;
unsigned long vmaddr, virtual_offset, file_offset;
unsigned long buffer, bss_size;
int error;
extern struct sysentvec linux_sysvec;
if (((a_out->a_magic >> 16) & 0xff) != 0x64)
return -1;
/*
* Set file/virtual offset based on a.out variant.
*/
switch ((int)(a_out->a_magic & 0xffff)) {
case 0413:
virtual_offset = 0;
file_offset = 1024;
break;
case 0314:
virtual_offset = 4096;
file_offset = 0;
break;
default:
return (-1);
}
bss_size = round_page(a_out->a_bss);
/*
* Check various fields in header for validity/bounds.
*/
if (a_out->a_entry < virtual_offset ||
a_out->a_entry >= virtual_offset + a_out->a_text ||
a_out->a_text % NBPG || a_out->a_data % NBPG)
return (-1);
/* text + data can't exceed file size */
if (a_out->a_data + a_out->a_text > iparams->attr->va_size)
return (EFAULT);
/*
* text/data/bss must not exceed limits
*/
if (a_out->a_text > MAXTSIZ || a_out->a_data + bss_size > MAXDSIZ ||
a_out->a_data+bss_size > iparams->proc->p_rlimit[RLIMIT_DATA].rlim_cur)
return (ENOMEM);
/* copy in arguments and/or environment from old process */
error = exec_extract_strings(iparams);
if (error)
return (error);
/*
* Destroy old process VM and create a new one (with a new stack)
*/
exec_new_vmspace(iparams);
/*
* Check if file_offset page aligned,.
* Currently we cannot handle misalinged file offsets,
* and so we read in the entire image (what a waste).
*/
if (file_offset & PGOFSET) {
#ifdef DEBUG
printf("imgact: Non page aligned binary %d\n", file_offset);
#endif
/*
* Map text read/execute
*/
vmaddr = virtual_offset;
error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr,
round_page(a_out->a_text), FALSE);
if (error)
return error;
error = vm_mmap(kernel_map, &buffer,
round_page(a_out->a_text + file_offset),
VM_PROT_READ, VM_PROT_READ, MAP_FILE,
(caddr_t) iparams->vnodep, trunc_page(file_offset));
if (error)
return error;
error = copyout((caddr_t)(buffer + file_offset), (caddr_t)vmaddr,
a_out->a_text);
if (error)
return error;
vm_map_remove(kernel_map, trunc_page(vmaddr),
round_page(a_out->a_text + file_offset));
error = vm_map_protect(&vmspace->vm_map, vmaddr,
round_page(a_out->a_text),
VM_PROT_EXECUTE|VM_PROT_READ, TRUE);
if (error)
return error;
/*
* Map data read/write
*/
vmaddr = virtual_offset + a_out->a_text;
error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr,
round_page(a_out->a_data + bss_size), FALSE);
if (error)
return error;
error = vm_mmap(kernel_map, &buffer,
round_page(a_out->a_data + file_offset),
VM_PROT_READ, VM_PROT_READ, MAP_FILE,
(caddr_t) iparams->vnodep,
trunc_page(a_out->a_text + file_offset));
if (error)
return error;
error = copyout((caddr_t)(buffer + file_offset),
(caddr_t)vmaddr,
a_out->a_data);
if (error)
return error;
vm_map_remove(kernel_map, trunc_page(vmaddr),
round_page(a_out->a_data + file_offset));
error = vm_map_protect(&vmspace->vm_map, vmaddr,
round_page(a_out->a_data + bss_size),
VM_PROT_WRITE|VM_PROT_READ, TRUE);
if (error)
return error;
}
else {
#ifdef DEBUG
printf("imgact: Page aligned binary %d\n", file_offset);
#endif
/*
* Map text read/execute
*/
vmaddr = virtual_offset;
error = vm_mmap(&vmspace->vm_map, &vmaddr, a_out->a_text,
VM_PROT_READ | VM_PROT_EXECUTE,
VM_PROT_READ | VM_PROT_EXECUTE | VM_PROT_WRITE,
MAP_PRIVATE | MAP_FIXED,
(caddr_t)iparams->vnodep, file_offset);
if (error)
return (error);
/*
* Map data read/write
*/
vmaddr = virtual_offset + a_out->a_text;
error = vm_mmap(&vmspace->vm_map, &vmaddr, a_out->a_data,
VM_PROT_READ | VM_PROT_WRITE,
VM_PROT_ALL, MAP_PRIVATE | MAP_FIXED,
(caddr_t)iparams->vnodep, file_offset + a_out->a_text);
if (error)
return (error);
/*
* Allocate demand-zeroed area for uninitialized data
*/
if (bss_size != 0) {
vmaddr = virtual_offset + a_out->a_text + a_out->a_data;
error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr,
bss_size, FALSE);
if (error)
return (error);
}
}
/* Fill in process VM information */
vmspace->vm_tsize = round_page(a_out->a_text) >> PAGE_SHIFT;
vmspace->vm_dsize = round_page(a_out->a_data + bss_size) >> PAGE_SHIFT;
vmspace->vm_taddr = (caddr_t)virtual_offset;
vmspace->vm_daddr = (caddr_t)virtual_offset + a_out->a_text;
/* Fill in image_params */
iparams->interpreted = 0;
iparams->entry_addr = a_out->a_entry;
iparams->proc->p_sysent = &linux_sysvec;
return (0);
}
/*
* Tell kern_execve.c about it, with a little help from the linker.
* Since `const' objects end up in the text segment, TEXT_SET is the
* correct directive to use.
*/
const struct execsw linux_execsw = { exec_linux_imgact, "linux" };
TEXT_SET(execsw_set, linux_execsw);