using std::endl;
using std::string;
using std::vector;
namespace {
mongo::AtomicUInt64 mmfNextId(0);
}
static size_t fetchMinOSPageSizeBytes() {
SYSTEM_INFO si;
GetSystemInfo(&si);
size_t minOSPageSizeBytes = si.dwPageSize;
minOSPageSizeBytesTest(minOSPageSizeBytes);
return minOSPageSizeBytes;
}
const size_t g_minOSPageSizeBytes = fetchMinOSPageSizeBytes();
// MapViewMutex
//
// Protects:
// 1. Ensures all MapViewOfFile/UnMapViewOfFile operations are serialized to reduce chance of
// "address in use" errors (error code 487)
// - These errors can still occur if the memory is used for other purposes
// (stack storage, heap)
// 2. Prevents calls to VirtualProtect while we remapping files.
// Lock Ordering:
// - If taken, must be after previewViews._m to prevent deadlocks
mutex mapViewMutex;
MAdvise::MAdvise(void *,unsigned, Advice) { }
MAdvise::~MAdvise() { }
namespace mongo {
static size_t fetchMinOSPageSizeBytes() {
size_t minOSPageSizeBytes = sysconf( _SC_PAGESIZE );
minOSPageSizeBytesTest(minOSPageSizeBytes);
return minOSPageSizeBytes;
}
const size_t g_minOSPageSizeBytes = fetchMinOSPageSizeBytes();
MemoryMappedFile::MemoryMappedFile() : _uniqueId(mmfNextId.fetchAndAdd(1)) {
fd = 0;
maphandle = 0;
len = 0;
created();
}
void MemoryMappedFile::close() {
LockMongoFilesShared::assertExclusivelyLocked();
for( vector<void*>::iterator i = views.begin(); i != views.end(); i++ ) {
munmap(*i,len);
}
views.clear();
if ( fd )
::close(fd);
fd = 0;
destroyed(); // cleans up from the master list of mmaps
}
#ifndef O_NOATIME
#define O_NOATIME (0)
#endif
#ifndef MAP_NORESERVE
#define MAP_NORESERVE (0)
#endif
namespace {
void* _pageAlign( void* p ) {
return (void*)((int64_t)p & ~(g_minOSPageSizeBytes-1));
}
class PageAlignTest : public StartupTest {
public:
void run() {
{
int64_t x = g_minOSPageSizeBytes + 123;
void* y = _pageAlign( reinterpret_cast<void*>( x ) );
invariant( g_minOSPageSizeBytes == reinterpret_cast<size_t>(y) );
}
{
int64_t a = static_cast<uint64_t>( numeric_limits<int>::max() );
a = a / g_minOSPageSizeBytes;
a = a * g_minOSPageSizeBytes;
// a should now be page aligned
// b is not page aligned
int64_t b = a + 123;
void* y = _pageAlign( reinterpret_cast<void*>( b ) );
invariant( a == reinterpret_cast<int64_t>(y) );
}
}
} pageAlignTest;
}
#if defined(__sunos__)
MAdvise::MAdvise(void *,unsigned, Advice) { }
MAdvise::~MAdvise() { }
#else
MAdvise::MAdvise(void *p, unsigned len, Advice a) {
_p = _pageAlign( p );
_len = len + static_cast<unsigned>( reinterpret_cast<size_t>(p) -
reinterpret_cast<size_t>(_p) );
int advice = 0;
switch ( a ) {
case Sequential:
advice = MADV_SEQUENTIAL;
break;
case Random:
advice = MADV_RANDOM;
break;
}
if ( madvise(_p,_len,advice ) ) {
error() << "madvise failed: " << errnoWithDescription();
}
}
MAdvise::~MAdvise() {
madvise(_p,_len,MADV_NORMAL);
}
#endif
void* MemoryMappedFile::map(const char *filename, unsigned long long &length, int options) {
// length may be updated by callee.
setFilename(filename);
FileAllocator::get()->allocateAsap( filename, length );
len = length;
massert( 10446 , str::stream() << "mmap: can't map area of size 0 file: " << filename, length > 0 );
fd = open(filename, O_RDWR | O_NOATIME);
if ( fd <= 0 ) {
log() << "couldn't open " << filename << ' ' << errnoWithDescription() << endl;
fd = 0; // our sentinel for not opened
return 0;
}
unsigned long long filelen = lseek(fd, 0, SEEK_END);
uassert(10447, str::stream() << "map file alloc failed, wanted: " << length << " filelen: " << filelen << ' ' << sizeof(size_t), filelen == length );
lseek( fd, 0, SEEK_SET );
void * view = mmap(NULL, length, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
if ( view == MAP_FAILED ) {
error() << " mmap() failed for " << filename << " len:" << length << " " << errnoWithDescription() << endl;
if ( errno == ENOMEM ) {
if( sizeof(void*) == 4 )
error() << "mmap failed with out of memory. You are using a 32-bit build and probably need to upgrade to 64" << endl;
else
error() << "mmap failed with out of memory. (64 bit build)" << endl;
}
return 0;
}
#if defined(__sunos__)
#warning madvise not supported on solaris yet
#else
if ( options & SEQUENTIAL ) {
if ( madvise( view , length , MADV_SEQUENTIAL ) ) {
warning() << "map: madvise failed for " << filename << ' ' << errnoWithDescription() << endl;
}
}
#endif
views.push_back( view );
return view;
}
void* MemoryMappedFile::createReadOnlyMap() {
void * x = mmap( /*start*/0 , len , PROT_READ , MAP_SHARED , fd , 0 );
if( x == MAP_FAILED ) {
if ( errno == ENOMEM ) {
if( sizeof(void*) == 4 )
error() << "mmap ro failed with out of memory. You are using a 32-bit build and probably need to upgrade to 64" << endl;
else
error() << "mmap ro failed with out of memory. (64 bit build)" << endl;
}
return 0;
}
return x;
}
void* MemoryMappedFile::createPrivateMap() {
void * x = mmap( /*start*/0 , len , PROT_READ|PROT_WRITE , MAP_PRIVATE|MAP_NORESERVE , fd , 0 );
if( x == MAP_FAILED ) {
if ( errno == ENOMEM ) {
if( sizeof(void*) == 4 ) {
error() << "mmap private failed with out of memory. You are using a 32-bit build and probably need to upgrade to 64" << endl;
}
else {
error() << "mmap private failed with out of memory. (64 bit build)" << endl;
}
}
else {
error() << "mmap private failed " << errnoWithDescription() << endl;
}
return 0;
}
views.push_back(x);
return x;
}
void* MemoryMappedFile::remapPrivateView(void *oldPrivateAddr) {
#if defined(__sunos__) // SERVER-8795
LockMongoFilesExclusive lockMongoFiles;
#endif
// don't unmap, just mmap over the old region
void * x = mmap( oldPrivateAddr, len , PROT_READ|PROT_WRITE , MAP_PRIVATE|MAP_NORESERVE|MAP_FIXED , fd , 0 );
if( x == MAP_FAILED ) {
int err = errno;
error() << "13601 Couldn't remap private view: " << errnoWithDescription(err) << endl;
log() << "aborting" << endl;
printMemInfo();
abort();
}
verify( x == oldPrivateAddr );
return x;
}
void MemoryMappedFile::flush(bool sync) {
if ( views.empty() || fd == 0 )
return;
bool useFsync = sync && !ProcessInfo::preferMsyncOverFSync();
if ( useFsync ?
fsync(fd) != 0 :
msync(viewForFlushing(), len, sync ? MS_SYNC : MS_ASYNC) ) {
// msync failed, this is very bad
log() << (useFsync ? "fsync failed: " : "msync failed: ") << errnoWithDescription()
<< " file: " << filename() << endl;
dataSyncFailedHandler();
}
}
class PosixFlushable : public MemoryMappedFile::Flushable {
public:
PosixFlushable( MemoryMappedFile* theFile, void* view , HANDLE fd , long len)
: _theFile( theFile ), _view( view ), _fd(fd), _len(len), _id(_theFile->getUniqueId()) {
}
void flush() {
if ( _view == NULL || _fd == 0 )
return;
if ( ProcessInfo::preferMsyncOverFSync() ?
msync(_view, _len, MS_SYNC ) == 0 :
fsync(_fd) == 0 ) {
return;
}
if ( errno == EBADF ) {
// ok, we were unlocked, so this file was closed
return;
}
// some error, lets see if we're supposed to exist
LockMongoFilesShared mmfilesLock;
std::set<MongoFile*> mmfs = MongoFile::getAllFiles();
std::set<MongoFile*>::const_iterator it = mmfs.find(_theFile);
if ( (it == mmfs.end()) || ((*it)->getUniqueId() != _id) ) {
log() << "msync failed with: " << errnoWithDescription()
<< " but file doesn't exist anymore, so ignoring";
// this was deleted while we were unlocked
return;
}
// we got an error, and we still exist, so this is bad, we fail
log() << "msync " << errnoWithDescription() << endl;
dataSyncFailedHandler();
}
MemoryMappedFile* _theFile;
void * _view;
HANDLE _fd;
long _len;
const uint64_t _id;
};
MemoryMappedFile::Flushable * MemoryMappedFile::prepareFlush() {
return new PosixFlushable( this, viewForFlushing(), fd, len);
}
} // namespace mongo
namespace mongo {
static size_t fetchMinOSPageSizeBytes() {
size_t minOSPageSizeBytes = sysconf( _SC_PAGESIZE );
minOSPageSizeBytesTest(minOSPageSizeBytes);
return minOSPageSizeBytes;
}
const size_t g_minOSPageSizeBytes = fetchMinOSPageSizeBytes();
MemoryMappedFile::MemoryMappedFile() {
fd = 0;
maphandle = 0;
len = 0;
created();
}
void MemoryMappedFile::close() {
LockMongoFilesShared::assertExclusivelyLocked();
for( vector<void*>::iterator i = views.begin(); i != views.end(); i++ ) {
munmap(*i,len);
}
views.clear();
if ( fd )
::close(fd);
fd = 0;
destroyed(); // cleans up from the master list of mmaps
}
#ifndef O_NOATIME
#define O_NOATIME (0)
#endif
#ifndef MAP_NORESERVE
#define MAP_NORESERVE (0)
#endif
#if defined(__sunos__)
MAdvise::MAdvise(void *,unsigned, Advice) { }
MAdvise::~MAdvise() { }
#else
MAdvise::MAdvise(void *p, unsigned len, Advice a) {
_p = (void*)((long)p & ~(g_minOSPageSizeBytes-1));
_len = len +((unsigned long long)p-(unsigned long long)_p);
int advice = 0;
switch ( a ) {
case Sequential:
advice = MADV_SEQUENTIAL;
break;
case Random:
advice = MADV_RANDOM;
break;
default:
verify(0);
}
if ( madvise(_p,_len,advice ) ) {
error() << "madvise failed: " << errnoWithDescription() << endl;
}
}
MAdvise::~MAdvise() {
madvise(_p,_len,MADV_NORMAL);
}
#endif
void* MemoryMappedFile::map(const char *filename, unsigned long long &length, int options) {
// length may be updated by callee.
setFilename(filename);
FileAllocator::get()->allocateAsap( filename, length );
len = length;
massert( 10446 , str::stream() << "mmap: can't map area of size 0 file: " << filename, length > 0 );
fd = open(filename, O_RDWR | O_NOATIME);
if ( fd <= 0 ) {
log() << "couldn't open " << filename << ' ' << errnoWithDescription() << endl;
fd = 0; // our sentinel for not opened
return 0;
}
unsigned long long filelen = lseek(fd, 0, SEEK_END);
uassert(10447, str::stream() << "map file alloc failed, wanted: " << length << " filelen: " << filelen << ' ' << sizeof(size_t), filelen == length );
lseek( fd, 0, SEEK_SET );
void * view = mmap(NULL, length, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
if ( view == MAP_FAILED ) {
error() << " mmap() failed for " << filename << " len:" << length << " " << errnoWithDescription() << endl;
if ( errno == ENOMEM ) {
if( sizeof(void*) == 4 )
error() << "mmap failed with out of memory. You are using a 32-bit build and probably need to upgrade to 64" << endl;
else
error() << "mmap failed with out of memory. (64 bit build)" << endl;
}
return 0;
}
#if defined(__sunos__)
#warning madvise not supported on solaris yet
#else
if ( options & SEQUENTIAL ) {
if ( madvise( view , length , MADV_SEQUENTIAL ) ) {
warning() << "map: madvise failed for " << filename << ' ' << errnoWithDescription() << endl;
}
}
#endif
views.push_back( view );
return view;
}
void* MemoryMappedFile::createReadOnlyMap() {
void * x = mmap( /*start*/0 , len , PROT_READ , MAP_SHARED , fd , 0 );
if( x == MAP_FAILED ) {
if ( errno == ENOMEM ) {
if( sizeof(void*) == 4 )
error() << "mmap ro failed with out of memory. You are using a 32-bit build and probably need to upgrade to 64" << endl;
else
error() << "mmap ro failed with out of memory. (64 bit build)" << endl;
}
return 0;
}
return x;
}
void* MemoryMappedFile::createPrivateMap() {
void * x = mmap( /*start*/0 , len , PROT_READ|PROT_WRITE , MAP_PRIVATE|MAP_NORESERVE , fd , 0 );
if( x == MAP_FAILED ) {
if ( errno == ENOMEM ) {
if( sizeof(void*) == 4 ) {
error() << "mmap private failed with out of memory. You are using a 32-bit build and probably need to upgrade to 64" << endl;
}
else {
error() << "mmap private failed with out of memory. (64 bit build)" << endl;
}
}
else {
error() << "mmap private failed " << errnoWithDescription() << endl;
}
return 0;
}
views.push_back(x);
return x;
}
void* MemoryMappedFile::remapPrivateView(void *oldPrivateAddr) {
// don't unmap, just mmap over the old region
void * x = mmap( oldPrivateAddr, len , PROT_READ|PROT_WRITE , MAP_PRIVATE|MAP_NORESERVE|MAP_FIXED , fd , 0 );
if( x == MAP_FAILED ) {
int err = errno;
error() << "13601 Couldn't remap private view: " << errnoWithDescription(err) << endl;
log() << "aborting" << endl;
printMemInfo();
abort();
}
verify( x == oldPrivateAddr );
return x;
}
void MemoryMappedFile::flush(bool sync) {
if ( views.empty() || fd == 0 )
return;
if ( msync(viewForFlushing(), len, sync ? MS_SYNC : MS_ASYNC) )
problem() << "msync " << errnoWithDescription() << endl;
}
class PosixFlushable : public MemoryMappedFile::Flushable {
public:
PosixFlushable( void * view , HANDLE fd , long len )
: _view( view ) , _fd( fd ) , _len(len) {
}
void flush() {
if ( _view && _fd )
if ( msync(_view, _len, MS_SYNC ) )
problem() << "msync " << errnoWithDescription() << endl;
}
void * _view;
HANDLE _fd;
long _len;
};
MemoryMappedFile::Flushable * MemoryMappedFile::prepareFlush() {
return new PosixFlushable( viewForFlushing() , fd , len );
}
} // namespace mongo
