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/*
* PARISC specific syscalls
*
* Copyright (C) 1999-2003 Matthew Wilcox <willy at parisc-linux.org>
* Copyright (C) 2000-2003 Paul Bame <bame at parisc-linux.org>
* Copyright (C) 2001 Thomas Bogendoerfer <tsbogend at parisc-linux.org>
* Copyright (C) 1999-2014 Helge Deller <deller@gmx.de>
*
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <asm/uaccess.h>
#include <asm/elf.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/linkage.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/shm.h>
#include <linux/syscalls.h>
#include <linux/utsname.h>
#include <linux/personality.h>
#include <linux/random.h>
/* we construct an artificial offset for the mapping based on the physical
* address of the kernel mapping variable */
#define GET_LAST_MMAP(filp) \
(filp ? ((unsigned long) filp->f_mapping) >> 8 : 0UL)
#define SET_LAST_MMAP(filp, val) \
{ /* nothing */ }
static int get_offset(unsigned int last_mmap)
{
return (last_mmap & (SHM_COLOUR-1)) >> PAGE_SHIFT;
}
static unsigned long shared_align_offset(unsigned int last_mmap,
unsigned long pgoff)
{
return (get_offset(last_mmap) + pgoff) << PAGE_SHIFT;
}
static inline unsigned long COLOR_ALIGN(unsigned long addr,
unsigned int last_mmap, unsigned long pgoff)
{
unsigned long base = (addr+SHM_COLOUR-1) & ~(SHM_COLOUR-1);
unsigned long off = (SHM_COLOUR-1) &
(shared_align_offset(last_mmap, pgoff) << PAGE_SHIFT);
return base + off;
}
/*
* Top of mmap area (just below the process stack).
*/
static unsigned long mmap_upper_limit(void)
{
unsigned long stack_base;
/* Limit stack size - see setup_arg_pages() in fs/exec.c */
stack_base = rlimit_max(RLIMIT_STACK);
if (stack_base > STACK_SIZE_MAX)
stack_base = STACK_SIZE_MAX;
return PAGE_ALIGN(STACK_TOP - stack_base);
}
unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
unsigned long len, unsigned long pgoff, unsigned long flags)
{
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
unsigned long task_size = TASK_SIZE;
int do_color_align, last_mmap;
struct vm_unmapped_area_info info;
if (len > task_size)
return -ENOMEM;
do_color_align = 0;
if (filp || (flags & MAP_SHARED))
do_color_align = 1;
last_mmap = GET_LAST_MMAP(filp);
if (flags & MAP_FIXED) {
if ((flags & MAP_SHARED) && last_mmap &&
(addr - shared_align_offset(last_mmap, pgoff))
& (SHM_COLOUR - 1))
return -EINVAL;
goto found_addr;
}
if (addr) {
if (do_color_align && last_mmap)
addr = COLOR_ALIGN(addr, last_mmap, pgoff);
else
addr = PAGE_ALIGN(addr);
vma = find_vma(mm, addr);
if (task_size - len >= addr &&
(!vma || addr + len <= vma->vm_start))
goto found_addr;
}
info.flags = 0;
info.length = len;
info.low_limit = mm->mmap_legacy_base;
info.high_limit = mmap_upper_limit();
info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
info.align_offset = shared_align_offset(last_mmap, pgoff);
addr = vm_unmapped_area(&info);
found_addr:
if (do_color_align && !last_mmap && !(addr & ~PAGE_MASK))
SET_LAST_MMAP(filp, addr - (pgoff << PAGE_SHIFT));
return addr;
}
unsigned long
arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
const unsigned long len, const unsigned long pgoff,
const unsigned long flags)
{
struct vm_area_struct *vma;
struct mm_struct *mm = current->mm;
unsigned long addr = addr0;
int do_color_align, last_mmap;
struct vm_unmapped_area_info info;
#ifdef CONFIG_64BIT
/* This should only ever run for 32-bit processes. */
BUG_ON(!test_thread_flag(TIF_32BIT));
#endif
/* requested length too big for entire address space */
if (len > TASK_SIZE)
return -ENOMEM;
do_color_align = 0;
if (filp || (flags & MAP_SHARED))
do_color_align = 1;
last_mmap = GET_LAST_MMAP(filp);
if (flags & MAP_FIXED) {
if ((flags & MAP_SHARED) && last_mmap &&
(addr - shared_align_offset(last_mmap, pgoff))
& (SHM_COLOUR - 1))
return -EINVAL;
goto found_addr;
}
/* requesting a specific address */
if (addr) {
if (do_color_align && last_mmap)
addr = COLOR_ALIGN(addr, last_mmap, pgoff);
else
addr = PAGE_ALIGN(addr);
vma = find_vma(mm, addr);
if (TASK_SIZE - len >= addr &&
(!vma || addr + len <= vma->vm_start))
goto found_addr;
}
info.flags = VM_UNMAPPED_AREA_TOPDOWN;
info.length = len;
info.low_limit = PAGE_SIZE;
info.high_limit = mm->mmap_base;
info.align_mask = last_mmap ? (PAGE_MASK & (SHM_COLOUR - 1)) : 0;
info.align_offset = shared_align_offset(last_mmap, pgoff);
addr = vm_unmapped_area(&info);
if (!(addr & ~PAGE_MASK))
goto found_addr;
VM_BUG_ON(addr != -ENOMEM);
/*
* A failed mmap() very likely causes application failure,
* so fall back to the bottom-up function here. This scenario
* can happen with large stack limits and large mmap()
* allocations.
*/
return arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
found_addr:
if (do_color_align && !last_mmap && !(addr & ~PAGE_MASK))
SET_LAST_MMAP(filp, addr - (pgoff << PAGE_SHIFT));
return addr;
}
static int mmap_is_legacy(void)
{
if (current->personality & ADDR_COMPAT_LAYOUT)
return 1;
/* parisc stack always grows up - so a unlimited stack should
* not be an indicator to use the legacy memory layout.
* if (rlimit(RLIMIT_STACK) == RLIM_INFINITY)
* return 1;
*/
return sysctl_legacy_va_layout;
}
static unsigned long mmap_rnd(void)
{
unsigned long rnd = 0;
/*
* 8 bits of randomness in 32bit mmaps, 20 address space bits
* 28 bits of randomness in 64bit mmaps, 40 address space bits
*/
if (current->flags & PF_RANDOMIZE) {
if (is_32bit_task())
rnd = get_random_int() % (1<<8);
else
rnd = get_random_int() % (1<<28);
}
return rnd << PAGE_SHIFT;
}
static unsigned long mmap_legacy_base(void)
{
return TASK_UNMAPPED_BASE + mmap_rnd();
}
/*
* This function, called very early during the creation of a new
* process VM image, sets up which VM layout function to use:
*/
void arch_pick_mmap_layout(struct mm_struct *mm)
{
mm->mmap_legacy_base = mmap_legacy_base();
mm->mmap_base = mmap_upper_limit();
if (mmap_is_legacy()) {
mm->mmap_base = mm->mmap_legacy_base;
mm->get_unmapped_area = arch_get_unmapped_area;
} else {
mm->get_unmapped_area = arch_get_unmapped_area_topdown;
}
}
asmlinkage unsigned long sys_mmap2(unsigned long addr, unsigned long len,
unsigned long prot, unsigned long flags, unsigned long fd,
unsigned long pgoff)
{
/* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE
we have. */
return sys_mmap_pgoff(addr, len, prot,
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