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
|
/* Memory mapping wrappers.
* ARM and MinGW ports contributed by Hideo Okuma and Tomoyuki Yoshimura at
* NICT.
*/
#include "util/mmap.hh"
#include "util/exception.hh"
#include "util/file.hh"
#include <iostream>
#include <assert.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <unistd.h>
#if defined(_WIN32) || defined(_WIN64)
#include <windows.h>
#include <io.h>
#else
#include <sys/mman.h>
#endif
namespace util {
long SizePage() {
#if defined(_WIN32) || defined(_WIN64)
SYSTEM_INFO si;
GetSystemInfo(&si);
return si.dwAllocationGranularity;
#else
return sysconf(_SC_PAGE_SIZE);
#endif
}
void SyncOrThrow(void *start, size_t length) {
#if defined(_WIN32) || defined(_WIN64)
UTIL_THROW_IF(!::FlushViewOfFile(start, length), ErrnoException, "Failed to sync mmap");
#else
UTIL_THROW_IF(msync(start, length, MS_SYNC), ErrnoException, "Failed to sync mmap");
#endif
}
void UnmapOrThrow(void *start, size_t length) {
#if defined(_WIN32) || defined(_WIN64)
UTIL_THROW_IF(!::UnmapViewOfFile(start), ErrnoException, "Failed to unmap a file");
#else
UTIL_THROW_IF(munmap(start, length), ErrnoException, "munmap failed");
#endif
}
scoped_mmap::~scoped_mmap() {
if (data_ != (void*)-1) {
try {
// Thanks Denis Filimonov for pointing out NFS likes msync first.
SyncOrThrow(data_, size_);
UnmapOrThrow(data_, size_);
} catch (const util::ErrnoException &e) {
std::cerr << e.what();
abort();
}
}
}
void scoped_memory::reset(void *data, std::size_t size, Alloc source) {
switch(source_) {
case MMAP_ALLOCATED:
scoped_mmap(data_, size_);
break;
case ARRAY_ALLOCATED:
delete [] reinterpret_cast<char*>(data_);
break;
case MALLOC_ALLOCATED:
free(data_);
break;
case NONE_ALLOCATED:
break;
}
data_ = data;
size_ = size;
source_ = source;
}
void scoped_memory::call_realloc(std::size_t size) {
assert(source_ == MALLOC_ALLOCATED || source_ == NONE_ALLOCATED);
void *new_data = realloc(data_, size);
if (!new_data) {
reset();
} else {
reset(new_data, size, MALLOC_ALLOCATED);
}
}
void *MapOrThrow(std::size_t size, bool for_write, int flags, bool prefault, int fd, uint64_t offset) {
#ifdef MAP_POPULATE // Linux specific
if (prefault) {
flags |= MAP_POPULATE;
}
#endif
#if defined(_WIN32) || defined(_WIN64)
int protectC = for_write ? PAGE_READWRITE : PAGE_READONLY;
int protectM = for_write ? FILE_MAP_WRITE : FILE_MAP_READ;
uint64_t total_size = size + offset;
HANDLE hMapping = CreateFileMapping((HANDLE)_get_osfhandle(fd), NULL, protectC, total_size >> 32, static_cast<DWORD>(total_size), NULL);
UTIL_THROW_IF(!hMapping, ErrnoException, "CreateFileMapping failed");
LPVOID ret = MapViewOfFile(hMapping, protectM, offset >> 32, offset, size);
CloseHandle(hMapping);
UTIL_THROW_IF(!ret, ErrnoException, "MapViewOfFile failed");
#else
int protect = for_write ? (PROT_READ | PROT_WRITE) : PROT_READ;
void *ret = mmap(NULL, size, protect, flags, fd, offset);
UTIL_THROW_IF(ret == MAP_FAILED, ErrnoException, "mmap failed for size " << size << " at offset " << offset);
#endif
return ret;
}
const int kFileFlags =
#if defined(_WIN32) || defined(_WIN64)
0 // MapOrThrow ignores flags on windows
#elif defined(MAP_FILE)
MAP_FILE | MAP_SHARED
#else
MAP_SHARED
#endif
;
void MapRead(LoadMethod method, int fd, uint64_t offset, std::size_t size, scoped_memory &out) {
switch (method) {
case LAZY:
out.reset(MapOrThrow(size, false, kFileFlags, false, fd, offset), size, scoped_memory::MMAP_ALLOCATED);
break;
case POPULATE_OR_LAZY:
#ifdef MAP_POPULATE
case POPULATE_OR_READ:
#endif
out.reset(MapOrThrow(size, false, kFileFlags, true, fd, offset), size, scoped_memory::MMAP_ALLOCATED);
break;
#ifndef MAP_POPULATE
case POPULATE_OR_READ:
#endif
case READ:
out.reset(malloc(size), size, scoped_memory::MALLOC_ALLOCATED);
if (!out.get()) UTIL_THROW(util::ErrnoException, "Allocating " << size << " bytes with malloc");
SeekOrThrow(fd, offset);
ReadOrThrow(fd, out.get(), size);
break;
}
}
// Allocates zeroed memory in to.
void MapAnonymous(std::size_t size, util::scoped_memory &to) {
to.reset();
#if defined(_WIN32) || defined(_WIN64)
to.reset(calloc(1, size), size, scoped_memory::MALLOC_ALLOCATED);
#else
to.reset(MapOrThrow(size, true,
# if defined(MAP_ANONYMOUS)
MAP_ANONYMOUS | MAP_PRIVATE // Linux
# else
MAP_ANON | MAP_PRIVATE // BSD
# endif
, false, -1, 0), size, scoped_memory::MMAP_ALLOCATED);
#endif
}
void *MapZeroedWrite(int fd, std::size_t size) {
ResizeOrThrow(fd, 0);
ResizeOrThrow(fd, size);
return MapOrThrow(size, true, kFileFlags, false, fd, 0);
}
void *MapZeroedWrite(const char *name, std::size_t size, scoped_fd &file) {
file.reset(CreateOrThrow(name));
try {
return MapZeroedWrite(file.get(), size);
} catch (ErrnoException &e) {
e << " in file " << name;
throw;
}
}
} // namespace util
|
