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
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
|
// data_file.h
/**
* Copyright (C) 2013 10gen Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the GNU Affero General Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#pragma once
#include "mongo/bson/util/builder.h"
#include "mongo/db/storage/mmap_v1/diskloc.h"
#include "mongo/db/storage/mmap_v1/durable_mapped_file.h"
#include "mongo/platform/bits.h"
namespace mongo {
class OperationContext;
#pragma pack(1)
class DataFileVersion {
public:
DataFileVersion(uint32_t major, uint32_t minor) : _major(major), _minor(minor) {}
static DataFileVersion defaultForNewFiles() {
return DataFileVersion(kCurrentMajor, kIndexes24AndNewer | kMayHave30Freelist);
}
Status isCompatibleWithCurrentCode() const {
if (_major != kCurrentMajor) {
StringBuilder sb;
sb << "The data files have major version " << _major
<< ", but this version of mongod only supports version " << kCurrentMajor;
return {ErrorCodes::MustUpgrade, sb.str()};
}
uint32_t unrecognizedMinorBits = _minor & ~kUsedMinorFlagsMask;
if (unrecognizedMinorBits) {
StringBuilder sb;
sb << "The data files use features not recognized by this version of mongod; the"
" feature bits in positions [ ";
bool firstIteration = true;
while (unrecognizedMinorBits) {
const int lowestSetBitPosition = countTrailingZeros64(unrecognizedMinorBits);
if (!firstIteration) {
sb << ", ";
}
sb << lowestSetBitPosition;
unrecognizedMinorBits ^= (1 << lowestSetBitPosition);
firstIteration = false;
}
sb << " ] aren't recognized by this version of mongod";
return {ErrorCodes::MustUpgrade, sb.str()};
}
const uint32_t indexCleanliness = _minor & kIndexPluginMask;
if (indexCleanliness != kIndexes24AndNewer && indexCleanliness != kIndexes22AndOlder) {
StringBuilder sb;
sb << "The data files have index plugin version " << indexCleanliness
<< ", but this version of mongod only supports versions " << kIndexes22AndOlder
<< " and " << kIndexes24AndNewer;
return {ErrorCodes::MustUpgrade, sb.str()};
}
// We are compatible with either setting of kMayHave30Freelist.
return Status::OK();
}
bool is24IndexClean() const {
return (_minor & kIndexPluginMask) == kIndexes24AndNewer;
}
void setIs24IndexClean() {
_minor = ((_minor & ~kIndexPluginMask) | kIndexes24AndNewer);
}
bool mayHave30Freelist() const {
return _minor & kMayHave30Freelist;
}
void setMayHave30Freelist() {
_minor |= kMayHave30Freelist;
}
bool getMayHaveCollationMetadata() const {
return _minor & kMayHaveCollationMetadata;
}
void setMayHaveCollationMetadata() {
_minor |= kMayHaveCollationMetadata;
}
uint32_t majorRaw() const {
return _major;
}
uint32_t minorRaw() const {
return _minor;
}
private:
static const uint32_t kCurrentMajor = 4;
// minor layout:
// first 4 bits - index plugin cleanliness.
// see IndexCatalog::_upgradeDatabaseMinorVersionIfNeeded for details
// 5th bit - 1 if started with 3.0-style freelist implementation (SERVER-14081)
// 6th bit - 1 if indexes or collections with a collation have been created.
// 7th through 31st bit - reserved and must be set to 0.
static const uint32_t kIndexPluginMask = 0xf;
static const uint32_t kIndexes22AndOlder = 5;
static const uint32_t kIndexes24AndNewer = 6;
static const uint32_t kMayHave30Freelist = (1 << 4);
static const uint32_t kMayHaveCollationMetadata = (1 << 5);
// All set bits we know about are covered by this mask.
static const uint32_t kUsedMinorFlagsMask =
kIndexPluginMask | kMayHave30Freelist | kMayHaveCollationMetadata;
uint32_t _major;
uint32_t _minor;
};
// Note: Intentionally not defining relational operators for DataFileVersion as there is no
// total ordering of all versions now that '_minor' is used as a bit vector.
#pragma pack()
/* a datafile - i.e. the "dbname.<#>" files :
----------------------
DataFileHeader
----------------------
Extent (for a particular namespace)
MmapV1RecordHeader
...
MmapV1RecordHeader (some chained for unused space)
----------------------
more Extents...
----------------------
*/
#pragma pack(1)
class DataFileHeader {
public:
DataFileVersion version;
int fileLength;
/**
* unused is the portion of the file that doesn't belong to any allocated extents. -1 = no more
*/
DiskLoc unused;
int unusedLength;
DiskLoc freeListStart;
DiskLoc freeListEnd;
char reserved[8192 - 4 * 4 - 8 * 3];
char data[4]; // first extent starts here
enum { HeaderSize = 8192 };
bool uninitialized() const {
return version.majorRaw() == 0;
}
void init(OperationContext* txn, int fileno, int filelength, const char* filename);
void checkUpgrade(OperationContext* txn);
bool isEmpty() const {
return uninitialized() || (unusedLength == fileLength - HeaderSize - 16);
}
};
#pragma pack()
class DataFile {
public:
DataFile(OperationContext* txn, int fn) : _fileNo(fn), mmf(txn), _mb(NULL) {}
/** @return true if found and opened. if uninitialized (prealloc only) does not open. */
Status openExisting(OperationContext* txn, const char* filename);
/** creates if DNE */
void open(OperationContext* txn,
const char* filename,
int requestedDataSize = 0,
bool preallocateOnly = false);
/**
* Must be called before destruction.
*/
void close(OperationContext* txn) {
LockMongoFilesExclusive lock(txn);
mmf.close(txn);
}
DiskLoc allocExtentArea(OperationContext* txn, int size);
DataFileHeader* getHeader() {
return header();
}
const DataFileHeader* getHeader() const {
return header();
}
HANDLE getFd() {
return mmf.getFd();
}
unsigned long long length() const {
return mmf.length();
}
/* return max size an extent may be */
static int maxSize();
/** fsync */
void flush(bool sync);
private:
friend class MmapV1ExtentManager;
void badOfs(int) const;
int _defaultSize() const;
void grow(DiskLoc dl, int size);
char* p() const {
return (char*)_mb;
}
DataFileHeader* header() {
return static_cast<DataFileHeader*>(_mb);
}
const DataFileHeader* header() const {
return static_cast<DataFileHeader*>(_mb);
}
const int _fileNo;
DurableMappedFile mmf;
void* _mb; // the memory mapped view
};
}
|