1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
|
// 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.flags = 0;
info.length = len;
info.low_limit = mm->mmap_base;
info.high_limit = TASK_SIZE;
info.align_mask = 0;
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
|
