124 lines
3.3 KiB
C
124 lines
3.3 KiB
C
/* elf-fdpic.c: ELF FDPIC memory layout management
|
|
*
|
|
* Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#include <linux/sched.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/elf-fdpic.h>
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* lay out the userspace VM according to our grand design
|
|
*/
|
|
#ifdef CONFIG_MMU
|
|
void elf_fdpic_arch_lay_out_mm(struct elf_fdpic_params *exec_params,
|
|
struct elf_fdpic_params *interp_params,
|
|
unsigned long *start_stack,
|
|
unsigned long *start_brk)
|
|
{
|
|
*start_stack = 0x02200000UL;
|
|
|
|
/* if the only executable is a shared object, assume that it is an interpreter rather than
|
|
* a true executable, and map it such that "ld.so --list" comes out right
|
|
*/
|
|
if (!(interp_params->flags & ELF_FDPIC_FLAG_PRESENT) &&
|
|
exec_params->hdr.e_type != ET_EXEC
|
|
) {
|
|
exec_params->load_addr = PAGE_SIZE;
|
|
|
|
*start_brk = 0x80000000UL;
|
|
}
|
|
else {
|
|
exec_params->load_addr = 0x02200000UL;
|
|
|
|
if ((exec_params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) ==
|
|
ELF_FDPIC_FLAG_INDEPENDENT
|
|
) {
|
|
exec_params->flags &= ~ELF_FDPIC_FLAG_ARRANGEMENT;
|
|
exec_params->flags |= ELF_FDPIC_FLAG_CONSTDISP;
|
|
}
|
|
}
|
|
|
|
} /* end elf_fdpic_arch_lay_out_mm() */
|
|
#endif
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* place non-fixed mmaps firstly in the bottom part of memory, working up, and then in the top part
|
|
* of memory, working down
|
|
*/
|
|
unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len,
|
|
unsigned long pgoff, unsigned long flags)
|
|
{
|
|
struct vm_area_struct *vma;
|
|
unsigned long limit;
|
|
|
|
if (len > TASK_SIZE)
|
|
return -ENOMEM;
|
|
|
|
/* only honour a hint if we're not going to clobber something doing so */
|
|
if (addr) {
|
|
addr = PAGE_ALIGN(addr);
|
|
vma = find_vma(current->mm, addr);
|
|
if (TASK_SIZE - len >= addr &&
|
|
(!vma || addr + len <= vma->vm_start))
|
|
goto success;
|
|
}
|
|
|
|
/* search between the bottom of user VM and the stack grow area */
|
|
addr = PAGE_SIZE;
|
|
limit = (current->mm->start_stack - 0x00200000);
|
|
if (addr + len <= limit) {
|
|
limit -= len;
|
|
|
|
if (addr <= limit) {
|
|
vma = find_vma(current->mm, PAGE_SIZE);
|
|
for (; vma; vma = vma->vm_next) {
|
|
if (addr > limit)
|
|
break;
|
|
if (addr + len <= vma->vm_start)
|
|
goto success;
|
|
addr = vma->vm_end;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* search from just above the WorkRAM area to the top of memory */
|
|
addr = PAGE_ALIGN(0x80000000);
|
|
limit = TASK_SIZE - len;
|
|
if (addr <= limit) {
|
|
vma = find_vma(current->mm, addr);
|
|
for (; vma; vma = vma->vm_next) {
|
|
if (addr > limit)
|
|
break;
|
|
if (addr + len <= vma->vm_start)
|
|
goto success;
|
|
addr = vma->vm_end;
|
|
}
|
|
|
|
if (!vma && addr <= limit)
|
|
goto success;
|
|
}
|
|
|
|
#if 0
|
|
printk("[area] l=%lx (ENOMEM) f='%s'\n",
|
|
len, filp ? filp->f_path.dentry->d_name.name : "");
|
|
#endif
|
|
return -ENOMEM;
|
|
|
|
success:
|
|
#if 0
|
|
printk("[area] l=%lx ad=%lx f='%s'\n",
|
|
len, addr, filp ? filp->f_path.dentry->d_name.name : "");
|
|
#endif
|
|
return addr;
|
|
} /* end arch_get_unmapped_area() */
|