Permalink
Fetching contributors…
Cannot retrieve contributors at this time
214 lines (183 sloc) 7.22 KB
// mmap_win.cpp
/* Copyright 2009 10gen Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "pch.h"
#include "mmap.h"
#include "text.h"
#include <windows.h>
namespace mongo {
mutex mapViewMutex("mapView");
MemoryMappedFile::MemoryMappedFile()
: _flushMutex(new mutex("flushMutex")) {
fd = 0;
maphandle = 0;
len = 0;
created();
}
void MemoryMappedFile::close() {
for( vector<void*>::iterator i = views.begin(); i != views.end(); i++ ) {
UnmapViewOfFile(*i);
}
views.clear();
if ( maphandle )
CloseHandle(maphandle);
maphandle = 0;
if ( fd )
CloseHandle(fd);
fd = 0;
}
unsigned long long mapped = 0;
void* MemoryMappedFile::remapPrivateView(void *oldPrivateAddr) {
// the mutex is to assure we get the same address on the remap
scoped_lock lk(mapViewMutex);
bool ok = UnmapViewOfFile(oldPrivateAddr);
assert(ok);
// we want the new address to be the same as the old address in case things keep pointers around (as namespaceindex does).
void *p = MapViewOfFileEx(maphandle, FILE_MAP_COPY, 0, 0,
/*dwNumberOfBytesToMap 0 means to eof*/0 /*len*/,
oldPrivateAddr);
assert(p);
assert(p == oldPrivateAddr);
return p;
}
void* MemoryMappedFile::createPrivateMap() {
assert( maphandle );
scoped_lock lk(mapViewMutex);
void *p = MapViewOfFile(maphandle, FILE_MAP_COPY, /*f ofs hi*/0, /*f ofs lo*/ 0, /*dwNumberOfBytesToMap 0 means to eof*/0);
if ( p == 0 ) {
DWORD e = GetLastError();
log() << "createPrivateMap failed " << filename() << " " << errnoWithDescription(e) << endl;
}
else {
views.push_back(p);
}
return p;
}
void* MemoryMappedFile::createReadOnlyMap() {
assert( maphandle );
scoped_lock lk(mapViewMutex);
void *p = MapViewOfFile(maphandle, FILE_MAP_READ, /*f ofs hi*/0, /*f ofs lo*/ 0, /*dwNumberOfBytesToMap 0 means to eof*/0);
if ( p == 0 ) {
DWORD e = GetLastError();
log() << "FILE_MAP_READ MapViewOfFile failed " << filename() << " " << errnoWithDescription(e) << endl;
}
else {
views.push_back(p);
}
return p;
}
void* MemoryMappedFile::map(const char *filenameIn, unsigned long long &length, int options) {
setFilename(filenameIn);
/* big hack here: Babble uses db names with colons. doesn't seem to work on windows. temporary perhaps. */
char filename[256];
strncpy(filename, filenameIn, 255);
filename[255] = 0;
{
size_t len = strlen( filename );
for ( size_t i=len-1; i>=0; i-- ) {
if ( filename[i] == '/' ||
filename[i] == '\\' )
break;
if ( filename[i] == ':' )
filename[i] = '_';
}
}
updateLength( filename, length );
{
DWORD createOptions = FILE_ATTRIBUTE_NORMAL;
if ( options & SEQUENTIAL )
createOptions |= FILE_FLAG_SEQUENTIAL_SCAN;
DWORD rw = GENERIC_READ | GENERIC_WRITE;
fd = CreateFile(
toNativeString(filename).c_str(),
rw, // desired access
FILE_SHARE_WRITE | FILE_SHARE_READ, // share mode
NULL, // security
OPEN_ALWAYS, // create disposition
createOptions , // flags
NULL); // hTempl
if ( fd == INVALID_HANDLE_VALUE ) {
DWORD e = GetLastError();
log() << "Create/OpenFile failed " << filename << " errno:" << e << endl;
return 0;
}
}
mapped += length;
{
DWORD flProtect = PAGE_READWRITE; //(options & READONLY)?PAGE_READONLY:PAGE_READWRITE;
maphandle = CreateFileMapping(fd, NULL, flProtect,
length >> 32 /*maxsizehigh*/,
(unsigned) length /*maxsizelow*/,
NULL/*lpName*/);
if ( maphandle == NULL ) {
DWORD e = GetLastError(); // log() call was killing lasterror before we get to that point in the stream
log() << "CreateFileMapping failed " << filename << ' ' << errnoWithDescription(e) << endl;
return 0;
}
}
void *view = 0;
{
scoped_lock lk(mapViewMutex);
DWORD access = (options&READONLY)? FILE_MAP_READ : FILE_MAP_ALL_ACCESS;
view = MapViewOfFile(maphandle, access, /*f ofs hi*/0, /*f ofs lo*/ 0, /*dwNumberOfBytesToMap 0 means to eof*/0);
}
if ( view == 0 ) {
DWORD e = GetLastError();
log() << "MapViewOfFile failed " << filename << " " << errnoWithDescription(e) << endl;
}
else {
views.push_back(view);
}
len = length;
return view;
}
class WindowsFlushable : public MemoryMappedFile::Flushable {
public:
WindowsFlushable( void * view , HANDLE fd , string filename , boost::shared_ptr<mutex> flushMutex )
: _view(view) , _fd(fd) , _filename(filename) , _flushMutex(flushMutex)
{}
void flush() {
if (!_view || !_fd)
return;
scoped_lock lk(*_flushMutex);
bool success = FlushViewOfFile(_view, 0); // 0 means whole mapping
if (!success) {
int err = GetLastError();
out() << "FlushViewOfFile failed " << err << " file: " << _filename << endl;
}
success = FlushFileBuffers(_fd);
if (!success) {
int err = GetLastError();
out() << "FlushFileBuffers failed " << err << " file: " << _filename << endl;
}
}
void * _view;
HANDLE _fd;
string _filename;
boost::shared_ptr<mutex> _flushMutex;
};
void MemoryMappedFile::flush(bool sync) {
uassert(13056, "Async flushing not supported on windows", sync);
if( !views.empty() ) {
WindowsFlushable f( views[0] , fd , filename() , _flushMutex);
f.flush();
}
}
MemoryMappedFile::Flushable * MemoryMappedFile::prepareFlush() {
return new WindowsFlushable( views.empty() ? 0 : views[0] , fd , filename() , _flushMutex );
}
void MemoryMappedFile::_lock() {}
void MemoryMappedFile::_unlock() {}
}