| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * ARC700 mmap |
| * |
| * (started from arm version - for VIPT alias handling) |
| * |
| * Copyright (C) 2013 Synopsys, Inc. (www.synopsys.com) |
| */ |
| |
| #include <linux/fs.h> |
| #include <linux/mm.h> |
| #include <linux/mman.h> |
| #include <linux/sched/mm.h> |
| |
| #include <asm/cacheflush.h> |
| |
| /* |
| * Ensure that shared mappings are correctly aligned to |
| * avoid aliasing issues with VIPT caches. |
| * We need to ensure that |
| * a specific page of an object is always mapped at a multiple of |
| * SHMLBA bytes. |
| */ |
| 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; |
| struct vm_unmapped_area_info info = {}; |
| |
| /* |
| * We enforce the MAP_FIXED case. |
| */ |
| if (flags & MAP_FIXED) { |
| if (flags & MAP_SHARED && |
| (addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)) |
| return -EINVAL; |
| return addr; |
| } |
| |
| if (len > TASK_SIZE) |
| return -ENOMEM; |
| |
| if (addr) { |
| addr = PAGE_ALIGN(addr); |
| |
| vma = find_vma(mm, addr); |
| if (TASK_SIZE - len >= addr && |
| (!vma || addr + len <= vm_start_gap(vma))) |
| return addr; |
| } |
| |
| info.length = len; |
| info.low_limit = mm->mmap_base; |
| info.high_limit = TASK_SIZE; |
| info.align_offset = pgoff << PAGE_SHIFT; |
| return vm_unmapped_area(&info); |
| } |
| |
| static const pgprot_t protection_map[16] = { |
| [VM_NONE] = PAGE_U_NONE, |
| [VM_READ] = PAGE_U_R, |
| [VM_WRITE] = PAGE_U_R, |
| [VM_WRITE | VM_READ] = PAGE_U_R, |
| [VM_EXEC] = PAGE_U_X_R, |
| [VM_EXEC | VM_READ] = PAGE_U_X_R, |
| [VM_EXEC | VM_WRITE] = PAGE_U_X_R, |
| [VM_EXEC | VM_WRITE | VM_READ] = PAGE_U_X_R, |
| [VM_SHARED] = PAGE_U_NONE, |
| [VM_SHARED | VM_READ] = PAGE_U_R, |
| [VM_SHARED | VM_WRITE] = PAGE_U_W_R, |
| [VM_SHARED | VM_WRITE | VM_READ] = PAGE_U_W_R, |
| [VM_SHARED | VM_EXEC] = PAGE_U_X_R, |
| [VM_SHARED | VM_EXEC | VM_READ] = PAGE_U_X_R, |
| [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_U_X_W_R, |
| [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_U_X_W_R |
| }; |
| DECLARE_VM_GET_PAGE_PROT |