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 */
24unsigned long
25arch_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
63static 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};
81DECLARE_VM_GET_PAGE_PROT
82