1 // SPDX-License-Identifier: GPL-2.0-only <<
2 /* 1 /*
3 * ARC700 mmap !! 2 * This file is subject to the terms and conditions of the GNU General Public
>> 3 * License. See the file "COPYING" in the main directory of this archive
>> 4 * for more details.
4 * 5 *
5 * (started from arm version - for VIPT alias !! 6 * Copyright (C) 2011 Wind River Systems,
6 * !! 7 * written by Ralf Baechle <ralf@linux-mips.org>
7 * Copyright (C) 2013 Synopsys, Inc. (www.syno <<
8 */ 8 */
9 !! 9 #include <linux/compiler.h>
10 #include <linux/fs.h> !! 10 #include <linux/elf-randomize.h>
>> 11 #include <linux/errno.h>
11 #include <linux/mm.h> 12 #include <linux/mm.h>
12 #include <linux/mman.h> 13 #include <linux/mman.h>
>> 14 #include <linux/export.h>
>> 15 #include <linux/personality.h>
>> 16 #include <linux/random.h>
>> 17 #include <linux/sched/signal.h>
13 #include <linux/sched/mm.h> 18 #include <linux/sched/mm.h>
14 19
15 #include <asm/cacheflush.h> !! 20 unsigned long shm_align_mask = PAGE_SIZE - 1; /* Sane caches */
>> 21 EXPORT_SYMBOL(shm_align_mask);
16 22
17 /* !! 23 #define COLOUR_ALIGN(addr, pgoff) \
18 * Ensure that shared mappings are correctly a !! 24 ((((addr) + shm_align_mask) & ~shm_align_mask) + \
19 * avoid aliasing issues with VIPT caches. !! 25 (((pgoff) << PAGE_SHIFT) & shm_align_mask))
20 * We need to ensure that !! 26
21 * a specific page of an object is always mapp !! 27 enum mmap_allocation_direction {UP, DOWN};
22 * SHMLBA bytes. !! 28
23 */ !! 29 static unsigned long arch_get_unmapped_area_common(struct file *filp,
24 unsigned long !! 30 unsigned long addr0, unsigned long len, unsigned long pgoff,
25 arch_get_unmapped_area(struct file *filp, unsi !! 31 unsigned long flags, enum mmap_allocation_direction dir)
26 unsigned long len, unsigned lo <<
27 unsigned long flags, vm_flags_ <<
28 { 32 {
29 struct mm_struct *mm = current->mm; 33 struct mm_struct *mm = current->mm;
30 struct vm_area_struct *vma; 34 struct vm_area_struct *vma;
>> 35 unsigned long addr = addr0;
>> 36 int do_color_align;
31 struct vm_unmapped_area_info info = {} 37 struct vm_unmapped_area_info info = {};
32 38
33 /* !! 39 if (unlikely(len > TASK_SIZE))
34 * We enforce the MAP_FIXED case. !! 40 return -ENOMEM;
35 */ !! 41
36 if (flags & MAP_FIXED) { 42 if (flags & MAP_FIXED) {
37 if (flags & MAP_SHARED && !! 43 /* Even MAP_FIXED mappings must reside within TASK_SIZE */
38 (addr - (pgoff << PAGE_SHI !! 44 if (TASK_SIZE - len < addr)
>> 45 return -EINVAL;
>> 46
>> 47 /*
>> 48 * We do not accept a shared mapping if it would violate
>> 49 * cache aliasing constraints.
>> 50 */
>> 51 if ((flags & MAP_SHARED) &&
>> 52 ((addr - (pgoff << PAGE_SHIFT)) & shm_align_mask))
39 return -EINVAL; 53 return -EINVAL;
40 return addr; 54 return addr;
41 } 55 }
42 56
43 if (len > TASK_SIZE) !! 57 do_color_align = 0;
44 return -ENOMEM; !! 58 if (filp || (flags & MAP_SHARED))
>> 59 do_color_align = 1;
45 60
>> 61 /* requesting a specific address */
46 if (addr) { 62 if (addr) {
47 addr = PAGE_ALIGN(addr); !! 63 if (do_color_align)
>> 64 addr = COLOUR_ALIGN(addr, pgoff);
>> 65 else
>> 66 addr = PAGE_ALIGN(addr);
48 67
49 vma = find_vma(mm, addr); 68 vma = find_vma(mm, addr);
50 if (TASK_SIZE - len >= addr && 69 if (TASK_SIZE - len >= addr &&
51 (!vma || addr + len <= vm_ 70 (!vma || addr + len <= vm_start_gap(vma)))
52 return addr; 71 return addr;
53 } 72 }
54 73
55 info.length = len; 74 info.length = len;
>> 75 info.align_mask = do_color_align ? (PAGE_MASK & shm_align_mask) : 0;
>> 76 info.align_offset = pgoff << PAGE_SHIFT;
>> 77
>> 78 if (dir == DOWN) {
>> 79 info.flags = VM_UNMAPPED_AREA_TOPDOWN;
>> 80 info.low_limit = PAGE_SIZE;
>> 81 info.high_limit = mm->mmap_base;
>> 82 addr = vm_unmapped_area(&info);
>> 83
>> 84 if (!(addr & ~PAGE_MASK))
>> 85 return addr;
>> 86
>> 87 /*
>> 88 * A failed mmap() very likely causes application failure,
>> 89 * so fall back to the bottom-up function here. This scenario
>> 90 * can happen with large stack limits and large mmap()
>> 91 * allocations.
>> 92 */
>> 93 }
>> 94
56 info.low_limit = mm->mmap_base; 95 info.low_limit = mm->mmap_base;
57 info.high_limit = TASK_SIZE; 96 info.high_limit = TASK_SIZE;
58 info.align_offset = pgoff << PAGE_SHIF <<
59 return vm_unmapped_area(&info); 97 return vm_unmapped_area(&info);
60 } 98 }
61 99
62 static const pgprot_t protection_map[16] = { !! 100 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr0,
63 [VM_NONE] !! 101 unsigned long len, unsigned long pgoff, unsigned long flags,
64 [VM_READ] !! 102 vm_flags_t vm_flags)
65 [VM_WRITE] !! 103 {
66 [VM_WRITE | VM_READ] !! 104 return arch_get_unmapped_area_common(filp,
67 [VM_EXEC] !! 105 addr0, len, pgoff, flags, UP);
68 [VM_EXEC | VM_READ] !! 106 }
69 [VM_EXEC | VM_WRITE] !! 107
70 [VM_EXEC | VM_WRITE | VM_READ] !! 108 /*
71 [VM_SHARED] !! 109 * There is no need to export this but sched.h declares the function as
72 [VM_SHARED | VM_READ] !! 110 * extern so making it static here results in an error.
73 [VM_SHARED | VM_WRITE] !! 111 */
74 [VM_SHARED | VM_WRITE | VM_READ] !! 112 unsigned long arch_get_unmapped_area_topdown(struct file *filp,
75 [VM_SHARED | VM_EXEC] !! 113 unsigned long addr0, unsigned long len, unsigned long pgoff,
76 [VM_SHARED | VM_EXEC | VM_READ] !! 114 unsigned long flags, vm_flags_t vm_flags)
77 [VM_SHARED | VM_EXEC | VM_WRITE] !! 115 {
78 [VM_SHARED | VM_EXEC | VM_WRITE | VM_R !! 116 return arch_get_unmapped_area_common(filp,
79 }; !! 117 addr0, len, pgoff, flags, DOWN);
80 DECLARE_VM_GET_PAGE_PROT !! 118 }
>> 119
>> 120 bool __virt_addr_valid(const volatile void *kaddr)
>> 121 {
>> 122 unsigned long vaddr = (unsigned long)kaddr;
>> 123
>> 124 if ((vaddr < PAGE_OFFSET) || (vaddr >= MAP_BASE))
>> 125 return false;
>> 126
>> 127 return pfn_valid(PFN_DOWN(virt_to_phys(kaddr)));
>> 128 }
>> 129 EXPORT_SYMBOL_GPL(__virt_addr_valid);
81 130
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