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/*
* Copyright (c) 2001-2005 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Authors: Nathan Binkert
*/
/** @file
* Disk Image Definitions
*/
#include "dev/storage/disk_image.hh"
#include <sys/types.h>
#include <sys/uio.h>
#include <unistd.h>
#include <cerrno>
#include <cstring>
#include <fstream>
#include <string>
#include "base/callback.hh"
#include "base/misc.hh"
#include "base/trace.hh"
#include "debug/DiskImageRead.hh"
#include "debug/DiskImageWrite.hh"
#include "sim/byteswap.hh"
#include "sim/sim_exit.hh"
using namespace std;
////////////////////////////////////////////////////////////////////////
//
// Raw Disk image
//
RawDiskImage::RawDiskImage(const Params* p)
: DiskImage(p), disk_size(0)
{ open(p->image_file, p->read_only); }
RawDiskImage::~RawDiskImage()
{ close(); }
void
RawDiskImage::notifyFork()
{
if (initialized && !readonly)
panic("Attempting to fork system with read-write raw disk image.");
const Params *p(dynamic_cast<const Params *>(params()));
close();
open(p->image_file, p->read_only);
}
void
RawDiskImage::open(const string &filename, bool rd_only)
{
if (!filename.empty()) {
initialized = true;
readonly = rd_only;
file = filename;
ios::openmode mode = ios::in | ios::binary;
if (!readonly)
mode |= ios::out;
stream.open(file.c_str(), mode);
if (!stream.is_open())
panic("Error opening %s", filename);
}
}
void
RawDiskImage::close()
{
stream.close();
}
std::streampos
RawDiskImage::size() const
{
if (disk_size == 0) {
if (!stream.is_open())
panic("file not open!\n");
stream.seekg(0, ios::end);
disk_size = stream.tellg();
}
return disk_size / SectorSize;
}
std::streampos
RawDiskImage::read(uint8_t *data, std::streampos offset) const
{
if (!initialized)
panic("RawDiskImage not initialized");
if (!stream.is_open())
panic("file not open!\n");
stream.seekg(offset * SectorSize, ios::beg);
if (!stream.good())
panic("Could not seek to location in file");
streampos pos = stream.tellg();
stream.read((char *)data, SectorSize);
DPRINTF(DiskImageRead, "read: offset=%d\n", (uint64_t)offset);
DDUMP(DiskImageRead, data, SectorSize);
return stream.tellg() - pos;
}
std::streampos
RawDiskImage::write(const uint8_t *data, std::streampos offset)
{
if (!initialized)
panic("RawDiskImage not initialized");
if (readonly)
panic("Cannot write to a read only disk image");
if (!stream.is_open())
panic("file not open!\n");
stream.seekp(offset * SectorSize, ios::beg);
if (!stream.good())
panic("Could not seek to location in file");
DPRINTF(DiskImageWrite, "write: offset=%d\n", (uint64_t)offset);
DDUMP(DiskImageWrite, data, SectorSize);
streampos pos = stream.tellp();
stream.write((const char *)data, SectorSize);
return stream.tellp() - pos;
}
RawDiskImage *
RawDiskImageParams::create()
{
return new RawDiskImage(this);
}
////////////////////////////////////////////////////////////////////////
//
// Copy on Write Disk image
//
const uint32_t CowDiskImage::VersionMajor = 1;
const uint32_t CowDiskImage::VersionMinor = 0;
class CowDiskCallback : public Callback
{
private:
CowDiskImage *image;
public:
CowDiskCallback(CowDiskImage *i) : image(i) {}
void process() { image->save(); delete this; }
};
CowDiskImage::CowDiskImage(const Params *p)
: DiskImage(p), filename(p->image_file), child(p->child), table(NULL)
{
if (filename.empty()) {
initSectorTable(p->table_size);
} else {
if (!open(filename)) {
if (p->read_only)
fatal("could not open read-only file");
initSectorTable(p->table_size);
}
if (!p->read_only)
registerExitCallback(new CowDiskCallback(this));
}
}
CowDiskImage::~CowDiskImage()
{
SectorTable::iterator i = table->begin();
SectorTable::iterator end = table->end();
while (i != end) {
delete (*i).second;
++i;
}
}
void
CowDiskImage::notifyFork()
{
if (!dynamic_cast<const Params *>(params())->read_only &&
!filename.empty()) {
inform("Disabling saving of COW image in forked child process.\n");
filename = "";
}
}
void
SafeRead(ifstream &stream, void *data, int count)
{
stream.read((char *)data, count);
if (!stream.is_open())
panic("file not open");
if (stream.eof())
panic("premature end-of-file");
if (stream.bad() || stream.fail())
panic("error reading cowdisk image");
}
template<class T>
void
SafeRead(ifstream &stream, T &data)
{
SafeRead(stream, &data, sizeof(data));
}
template<class T>
void
SafeReadSwap(ifstream &stream, T &data)
{
SafeRead(stream, &data, sizeof(data));
data = letoh(data); //is this the proper byte order conversion?
}
bool
CowDiskImage::open(const string &file)
{
ifstream stream(file.c_str());
if (!stream.is_open())
return false;
if (stream.fail() || stream.bad())
panic("Error opening %s", file);
uint64_t magic;
SafeRead(stream, magic);
if (memcmp(&magic, "COWDISK!", sizeof(magic)) != 0)
panic("Could not open %s: Invalid magic", file);
uint32_t major, minor;
SafeReadSwap(stream, major);
SafeReadSwap(stream, minor);
if (major != VersionMajor && minor != VersionMinor)
panic("Could not open %s: invalid version %d.%d != %d.%d",
file, major, minor, VersionMajor, VersionMinor);
uint64_t sector_count;
SafeReadSwap(stream, sector_count);
table = new SectorTable(sector_count);
for (uint64_t i = 0; i < sector_count; i++) {
uint64_t offset;
SafeReadSwap(stream, offset);
Sector *sector = new Sector;
SafeRead(stream, sector, sizeof(Sector));
assert(table->find(offset) == table->end());
(*table)[offset] = sector;
}
stream.close();
initialized = true;
return true;
}
void
CowDiskImage::initSectorTable(int hash_size)
{
table = new SectorTable(hash_size);
initialized = true;
}
void
SafeWrite(ofstream &stream, const void *data, int count)
{
stream.write((const char *)data, count);
if (!stream.is_open())
panic("file not open");
if (stream.eof())
panic("premature end-of-file");
if (stream.bad() || stream.fail())
panic("error reading cowdisk image");
}
template<class T>
void
SafeWrite(ofstream &stream, const T &data)
{
SafeWrite(stream, &data, sizeof(data));
}
template<class T>
void
SafeWriteSwap(ofstream &stream, const T &data)
{
T swappeddata = letoh(data); //is this the proper byte order conversion?
SafeWrite(stream, &swappeddata, sizeof(data));
}
void
CowDiskImage::save() const
{
// filename will be set to the empty string to disable saving of
// the COW image in a forked child process. Save will still be
// called because there is no easy way to unregister the exit
// callback.
if (!filename.empty())
save(filename);}
void
CowDiskImage::save(const string &file) const
{
if (!initialized)
panic("RawDiskImage not initialized");
ofstream stream(file.c_str());
if (!stream.is_open() || stream.fail() || stream.bad())
panic("Error opening %s", file);
uint64_t magic;
memcpy(&magic, "COWDISK!", sizeof(magic));
SafeWrite(stream, magic);
SafeWriteSwap(stream, (uint32_t)VersionMajor);
SafeWriteSwap(stream, (uint32_t)VersionMinor);
SafeWriteSwap(stream, (uint64_t)table->size());
uint64_t size = table->size();
SectorTable::iterator iter = table->begin();
SectorTable::iterator end = table->end();
for (uint64_t i = 0; i < size; i++) {
if (iter == end)
panic("Incorrect Table Size during save of COW disk image");
SafeWriteSwap(stream, (uint64_t)(*iter).first);
SafeWrite(stream, (*iter).second->data, sizeof(Sector));
++iter;
}
stream.close();
}
void
CowDiskImage::writeback()
{
SectorTable::iterator i = table->begin();
SectorTable::iterator end = table->end();
while (i != end) {
child->write((*i).second->data, (*i).first);
++i;
}
}
std::streampos
CowDiskImage::size() const
{ return child->size(); }
std::streampos
CowDiskImage::read(uint8_t *data, std::streampos offset) const
{
if (!initialized)
panic("CowDiskImage not initialized");
if (offset > size())
panic("access out of bounds");
SectorTable::const_iterator i = table->find(offset);
if (i == table->end())
return child->read(data, offset);
else {
memcpy(data, (*i).second->data, SectorSize);
DPRINTF(DiskImageRead, "read: offset=%d\n", (uint64_t)offset);
DDUMP(DiskImageRead, data, SectorSize);
return SectorSize;
}
}
std::streampos
CowDiskImage::write(const uint8_t *data, std::streampos offset)
{
if (!initialized)
panic("RawDiskImage not initialized");
if (offset > size())
panic("access out of bounds");
SectorTable::iterator i = table->find(offset);
if (i == table->end()) {
Sector *sector = new Sector;
memcpy(sector, data, SectorSize);
table->insert(make_pair(offset, sector));
} else {
memcpy((*i).second->data, data, SectorSize);
}
DPRINTF(DiskImageWrite, "write: offset=%d\n", (uint64_t)offset);
DDUMP(DiskImageWrite, data, SectorSize);
return SectorSize;
}
void
CowDiskImage::serialize(CheckpointOut &cp) const
{
string cowFilename = name() + ".cow";
SERIALIZE_SCALAR(cowFilename);
save(CheckpointIn::dir() + "/" + cowFilename);
}
void
CowDiskImage::unserialize(CheckpointIn &cp)
{
string cowFilename;
UNSERIALIZE_SCALAR(cowFilename);
cowFilename = cp.cptDir + "/" + cowFilename;
open(cowFilename);
}
CowDiskImage *
CowDiskImageParams::create()
{
return new CowDiskImage(this);
}