/* Copyright 2005 Andi Kleen, SuSE Labs. * Licensed under GPL, v.2 */ #include #include #include #include #include /* Notebook: move the mmap code from sys_x86_64.c over here. */ void arch_pick_mmap_layout(struct mm_struct *mm) { #ifdef CONFIG_IA32_EMULATION if (current_thread_info()->flags & _TIF_IA32) return ia32_pick_mmap_layout(mm); #endif mm->mmap_base = TASK_UNMAPPED_BASE; if (current->flags & PF_RANDOMIZE) { /* Add 28bit randomness which is about 40bits of address space because mmap base has to be page aligned. or ~1/128 of the total user VM (total user address space is 47bits) */ unsigned rnd = get_random_int() & 0xfffffff; mm->mmap_base += ((unsigned long)rnd) << PAGE_SHIFT; } mm->get_unmapped_area = arch_get_unmapped_area; mm->unmap_area = arch_unmap_area; }