1 /*
2 * Copyright 2006-2012, Haiku, Inc. All Rights Reserved.
3 * Distributed under the terms of the MIT License.
4 *
5 * Authors:
6 * Axel Dörfler, axeld@pinc-software.de
7 */
8
9
10 /*! Note, this class don't provide any locking whatsoever - you are
11 supposed to have a BPrivate::AppServerLink object around which
12 does the necessary locking.
13 However, this is not enforced in the methods here, you have to
14 take care for yourself!
15 */
16
17
18 #include "ServerMemoryAllocator.h"
19
20 #include <new>
21
22 #ifndef HAIKU_TARGET_PLATFORM_LIBBE_TEST
23 # include <syscalls.h>
24 #endif
25
26
27 static const size_t kReservedSize = 128 * 1024 * 1024;
28 static const size_t kReserveMaxSize = 32 * 1024 * 1024;
29
30
31 namespace BPrivate {
32
33
34 struct area_mapping {
35 area_id server_area;
36 area_id local_area;
37 uint8* local_base;
38 };
39
40
ServerMemoryAllocator()41 ServerMemoryAllocator::ServerMemoryAllocator()
42 :
43 fAreas(4)
44 {
45 }
46
47
~ServerMemoryAllocator()48 ServerMemoryAllocator::~ServerMemoryAllocator()
49 {
50 for (int32 i = fAreas.CountItems(); i-- > 0;) {
51 area_mapping* mapping = (area_mapping*)fAreas.ItemAt(i);
52
53 delete_area(mapping->local_area);
54 delete mapping;
55 }
56 }
57
58
59 status_t
InitCheck()60 ServerMemoryAllocator::InitCheck()
61 {
62 return B_OK;
63 }
64
65
66 status_t
AddArea(area_id serverArea,area_id & _area,uint8 * & _base,size_t size,bool readOnly)67 ServerMemoryAllocator::AddArea(area_id serverArea, area_id& _area,
68 uint8*& _base, size_t size, bool readOnly)
69 {
70 area_mapping* mapping = new (std::nothrow) area_mapping;
71 if (mapping == NULL || !fAreas.AddItem(mapping)) {
72 delete mapping;
73 return B_NO_MEMORY;
74 }
75
76 status_t status = B_ERROR;
77 uint32 addressSpec = B_ANY_ADDRESS;
78 void* base;
79 #ifndef HAIKU_TARGET_PLATFORM_LIBBE_TEST
80 if (!readOnly && size < kReserveMaxSize) {
81 // Reserve 128 MB of space for the area, but only if the area
82 // is smaller than 32 MB (else the address space waste would
83 // likely to be too large)
84 base = (void*)0x60000000;
85 status = _kern_reserve_address_range((addr_t*)&base, B_BASE_ADDRESS,
86 kReservedSize);
87 addressSpec = status == B_OK ? B_EXACT_ADDRESS : B_BASE_ADDRESS;
88 }
89 #endif
90
91 mapping->local_area = clone_area(readOnly
92 ? "server read-only memory" : "server_memory", &base, addressSpec,
93 B_CLONEABLE_AREA | B_READ_AREA | (readOnly ? 0 : B_WRITE_AREA),
94 serverArea);
95 if (mapping->local_area < B_OK) {
96 status = mapping->local_area;
97
98 fAreas.RemoveItem(mapping);
99 delete mapping;
100
101 return status;
102 }
103
104 mapping->server_area = serverArea;
105 mapping->local_base = (uint8*)base;
106
107 _area = mapping->local_area;
108 _base = mapping->local_base;
109
110 return B_OK;
111 }
112
113
114 void
RemoveArea(area_id serverArea)115 ServerMemoryAllocator::RemoveArea(area_id serverArea)
116 {
117 for (int32 i = fAreas.CountItems(); i-- > 0;) {
118 area_mapping* mapping = (area_mapping*)fAreas.ItemAt(i);
119
120 if (mapping->server_area == serverArea) {
121 // we found the area we should remove
122 delete_area(mapping->local_area);
123 delete mapping;
124 fAreas.RemoveItem(i);
125 break;
126 }
127 }
128 }
129
130
131 status_t
AreaAndBaseFor(area_id serverArea,area_id & _area,uint8 * & _base)132 ServerMemoryAllocator::AreaAndBaseFor(area_id serverArea, area_id& _area,
133 uint8*& _base)
134 {
135 // TODO: why not use a map?
136 for (int32 i = fAreas.CountItems(); i-- > 0;) {
137 area_mapping* mapping = (area_mapping*)fAreas.ItemAt(i);
138
139 if (mapping->server_area == serverArea) {
140 _area = mapping->local_area;
141 _base = mapping->local_base;
142 return B_OK;
143 }
144 }
145
146 return B_ERROR;
147 }
148
149
150 } // namespace BPrivate
151