projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
1 | /* elf-fdpic.c: ELF FDPIC memory layout management |
| 2 | * | |
| 3 | * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. | |
| 4 | * Written by David Howells (dhowells@redhat.com) | |
| 5 | * | |
| 6 | * This program is free software; you can redistribute it and/or | |
| 7 | * modify it under the terms of the GNU General Public License | |
| 8 | * as published by the Free Software Foundation; either version | |
| 9 | * 2 of the License, or (at your option) any later version. | |
| 10 | */ | |
| 11 | ||
| 12 | #include <linux/sched.h> | |
| 13 | #include <linux/mm.h> | |
| 14 | #include <linux/fs.h> | |
| 15 | #include <linux/elf-fdpic.h> | |
| 5616df20 | 16 | #include <asm/mman.h> |
| 1da177e4 LT |
17 | |
| 18 | /*****************************************************************************/ | |
| 19 | /* | |
| 20 | * lay out the userspace VM according to our grand design | |
| 21 | */ | |
| 22 | #ifdef CONFIG_MMU | |
| 23 | void elf_fdpic_arch_lay_out_mm(struct elf_fdpic_params *exec_params, | |
| 24 | struct elf_fdpic_params *interp_params, | |
| 25 | unsigned long *start_stack, | |
| 26 | unsigned long *start_brk) | |
| 27 | { | |
| 28 | *start_stack = 0x02200000UL; | |
| 29 | ||
| 30 | /* if the only executable is a shared object, assume that it is an interpreter rather than | |
| 31 | * a true executable, and map it such that "ld.so --list" comes out right | |
| 32 | */ | |
| 33 | if (!(interp_params->flags & ELF_FDPIC_FLAG_PRESENT) && | |
| 34 | exec_params->hdr.e_type != ET_EXEC | |
| 35 | ) { | |
| 36 | exec_params->load_addr = PAGE_SIZE; | |
| 37 | ||
| 38 | *start_brk = 0x80000000UL; | |
| 39 | } | |
| 40 | else { | |
| 41 | exec_params->load_addr = 0x02200000UL; | |
| 42 | ||
| 43 | if ((exec_params->flags & ELF_FDPIC_FLAG_ARRANGEMENT) == | |
| 44 | ELF_FDPIC_FLAG_INDEPENDENT | |
| 45 | ) { | |
| 46 | exec_params->flags &= ~ELF_FDPIC_FLAG_ARRANGEMENT; | |
| 47 | exec_params->flags |= ELF_FDPIC_FLAG_CONSTDISP; | |
| 48 | } | |
| 49 | } | |
| 50 | ||
| 51 | } /* end elf_fdpic_arch_lay_out_mm() */ | |
| 52 | #endif | |
| 53 | ||
| 54 | /*****************************************************************************/ | |
| 55 | /* | |
| 56 | * place non-fixed mmaps firstly in the bottom part of memory, working up, and then in the top part | |
| 57 | * of memory, working down | |
| 58 | */ | |
| 59 | unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, | |
| 60 | unsigned long pgoff, unsigned long flags) | |
| 61 | { | |
| 62 | struct vm_area_struct *vma; | |
| e759a798 | 63 | struct vm_unmapped_area_info info; |
| 1da177e4 LT |
64 | |
| 65 | if (len > TASK_SIZE) | |
| 66 | return -ENOMEM; | |
| 67 | ||
| 2fd3beba BH |
68 | /* handle MAP_FIXED */ |
| 69 | if (flags & MAP_FIXED) | |
| 70 | return addr; | |
| 71 | ||
| 1da177e4 LT |
72 | /* only honour a hint if we're not going to clobber something doing so */ |
| 73 | if (addr) { | |
| 74 | addr = PAGE_ALIGN(addr); | |
| 75 | vma = find_vma(current->mm, addr); | |
| 76 | if (TASK_SIZE - len >= addr && | |
| 77 | (!vma || addr + len <= vma->vm_start)) | |
| 78 | goto success; | |
| 79 | } | |
| 80 | ||
| 81 | /* search between the bottom of user VM and the stack grow area */ | |
| e759a798 ML |
82 | info.flags = 0; |
| 83 | info.length = len; | |
| 84 | info.low_limit = PAGE_SIZE; | |
| 85 | info.high_limit = (current->mm->start_stack - 0x00200000); | |
| 86 | info.align_mask = 0; | |
| 87 | info.align_offset = 0; | |
| 88 | addr = vm_unmapped_area(&info); | |
| 89 | if (!(addr & ~PAGE_MASK)) | |
| 90 | goto success; | |
| 91 | VM_BUG_ON(addr != -ENOMEM); | |
| 1da177e4 LT |
92 | |
| 93 | /* search from just above the WorkRAM area to the top of memory */ | |
| e759a798 ML |
94 | info.low_limit = PAGE_ALIGN(0x80000000); |
| 95 | info.high_limit = TASK_SIZE; | |
| 96 | addr = vm_unmapped_area(&info); | |
| 97 | if (!(addr & ~PAGE_MASK)) | |
| 98 | goto success; | |
| 99 | VM_BUG_ON(addr != -ENOMEM); | |
| 1da177e4 LT |
100 | |
| 101 | #if 0 | |
| 102 | printk("[area] l=%lx (ENOMEM) f='%s'\n", | |
| 1f70cecc | 103 | len, filp ? filp->f_path.dentry->d_name.name : ""); |
| 1da177e4 LT |
104 | #endif |
| 105 | return -ENOMEM; | |
| 106 | ||
| 107 | success: | |
| 108 | #if 0 | |
| 109 | printk("[area] l=%lx ad=%lx f='%s'\n", | |
| 1f70cecc | 110 | len, addr, filp ? filp->f_path.dentry->d_name.name : ""); |
| 1da177e4 LT |
111 | #endif |
| 112 | return addr; | |
| 113 | } /* end arch_get_unmapped_area() */ |