1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * ARC700 mmap 4 * 5 * (started from arm version - for VIPT alias handling) 6 * 7 * Copyright (C) 2013 Synopsys, Inc. (www.synopsys.com) 8 */ 9 10 #include <linux/fs.h> 11 #include <linux/mm.h> 12 #include <linux/mman.h> 13 #include <linux/sched/mm.h> 14 15 #include <asm/cacheflush.h> 16 17 /* 18 * Ensure that shared mappings are correctly aligned to 19 * avoid aliasing issues with VIPT caches. 20 * We need to ensure that 21 * a specific page of an object is always mapped at a multiple of 22 * SHMLBA bytes. 23 */ 24 unsigned long 25 arch_get_unmapped_area(struct file *filp, unsigned long addr, 26 unsigned long len, unsigned long pgoff, unsigned long flags) 27 { 28 struct mm_struct *mm = current->mm; 29 struct vm_area_struct *vma; 30 struct vm_unmapped_area_info info; 31 32 /* 33 * We enforce the MAP_FIXED case. 34 */ 35 if (flags & MAP_FIXED) { 36 if (flags & MAP_SHARED && 37 (addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)) 38 return -EINVAL; 39 return addr; 40 } 41 42 if (len > TASK_SIZE) 43 return -ENOMEM; 44 45 if (addr) { 46 addr = PAGE_ALIGN(addr); 47 48 vma = find_vma(mm, addr); 49 if (TASK_SIZE - len >= addr && 50 (!vma || addr + len <= vm_start_gap(vma))) 51 return addr; 52 } 53 54 info.flags = 0; 55 info.length = len; 56 info.low_limit = mm->mmap_base; 57 info.high_limit = TASK_SIZE; 58 info.align_mask = 0; 59 info.align_offset = pgoff << PAGE_SHIFT; 60 return vm_unmapped_area(&info); 61 } 62 63 static const pgprot_t protection_map[16] = { 64 [VM_NONE] = PAGE_U_NONE, 65 [VM_READ] = PAGE_U_R, 66 [VM_WRITE] = PAGE_U_R, 67 [VM_WRITE | VM_READ] = PAGE_U_R, 68 [VM_EXEC] = PAGE_U_X_R, 69 [VM_EXEC | VM_READ] = PAGE_U_X_R, 70 [VM_EXEC | VM_WRITE] = PAGE_U_X_R, 71 [VM_EXEC | VM_WRITE | VM_READ] = PAGE_U_X_R, 72 [VM_SHARED] = PAGE_U_NONE, 73 [VM_SHARED | VM_READ] = PAGE_U_R, 74 [VM_SHARED | VM_WRITE] = PAGE_U_W_R, 75 [VM_SHARED | VM_WRITE | VM_READ] = PAGE_U_W_R, 76 [VM_SHARED | VM_EXEC] = PAGE_U_X_R, 77 [VM_SHARED | VM_EXEC | VM_READ] = PAGE_U_X_R, 78 [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_U_X_W_R, 79 [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_U_X_W_R 80 }; 81 DECLARE_VM_GET_PAGE_PROT 82