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#include <linux/slab.h>
#include <linux/shm.h>
#include <linux/mman.h>
#include <linux/pagemap.h>
#include <linux/swap.h>
#include <linux/swapctl.h>
#include <linux/smp_lock.h>
#include <linux/init.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/personality.h>
#include <asm/uaccess.h>
#include <asm/pgalloc.h>
/*
static int direct_mapped(unsigned long addr)
{
direct_mmap_node_t * node;
struct list_head * curr;
struct list_head * direct_list = ¤t->mm->context.direct_list;
curr = direct_list->next;
while(curr != direct_list){
node = list_entry(curr, direct_mmap_node_t, list);
if(node->addr == addr)
break;
curr = curr->next;
}
if(curr == direct_list)
return 0;
return 1;
}
*/
/*
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;
if (len > TASK_SIZE)
return -ENOMEM;
if (addr) {
addr = PAGE_ALIGN(addr);
vma = find_vma(current->mm, addr);
if (TASK_SIZE - len >= addr &&
(!vma || addr + len <= vma->vm_start))
return addr;
}
addr = PAGE_ALIGN(TASK_UNMAPPED_BASE);
for (vma = find_vma(current->mm, addr); ; vma = vma->vm_next) {
if (TASK_SIZE - len < addr)
return -ENOMEM;
if ((!vma || addr + len <= vma->vm_start) && !direct_mapped(addr))
return addr;
addr = vma->vm_end;
}
}
*/
struct list_head *find_direct(struct list_head *list, unsigned long addr)
{
struct list_head * curr;
struct list_head * direct_list = ¤t->mm->context.direct_list;
direct_mmap_node_t * node;
for ( curr = direct_list->next; curr != direct_list; curr = curr->next )
{
node = list_entry(curr, direct_mmap_node_t, list);
if ( node->vm_start >= addr ) break;
}
return curr;
}
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;
direct_mmap_node_t * node;
struct list_head * curr;
struct list_head * direct_list = ¤t->mm->context.direct_list;
if (len > TASK_SIZE)
return -ENOMEM;
if ( addr )
{
addr = PAGE_ALIGN(addr);
vma = find_vma(current->mm, addr);
curr = find_direct(direct_list, addr);
node = list_entry(curr, direct_mmap_node_t, list);
if ( (TASK_SIZE - len >= addr) &&
(!vma || addr + len <= vma->vm_start) &&
((curr == direct_list) || addr + len <= node->vm_start) )
return addr;
}
addr = PAGE_ALIGN(TASK_UNMAPPED_BASE);
/* Find first VMA and direct_map nodes with vm_start > addr */
vma = find_vma(current->mm, addr);
curr = find_direct(direct_list, addr);
node = list_entry(curr, direct_mmap_node_t, list);
for ( ; ; )
{
if ( TASK_SIZE - len < addr ) return -ENOMEM;
if ( vma && ((curr == direct_list) || (vma->vm_start < node->vm_start)))
{
/* Do we fit before VMA node? */
if ( addr + len <= vma->vm_start ) return addr;
addr = vma->vm_end;
vma = vma->vm_next;
}
else if ( curr != direct_list )
{
/* Do we fit before direct_map node? */
if ( addr + len <= node->vm_start) return addr;
addr = node->vm_end;
curr = curr->next;
node = list_entry(curr, direct_mmap_node_t, list);
}
else
{
/* !vma && curr == direct_list */
return addr;
}
}
}
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