diff options
Diffstat (limited to 'dev/disk_image.hh')
-rw-r--r-- | dev/disk_image.hh | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/dev/disk_image.hh b/dev/disk_image.hh new file mode 100644 index 000000000..2cfa1490a --- /dev/null +++ b/dev/disk_image.hh @@ -0,0 +1,130 @@ +/* + * Copyright (c) 2003 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. + */ + +/* @file + * Disk Image Interfaces + */ + +#ifndef __DISK_IMAGE_HH__ +#define __DISK_IMAGE_HH__ + +#include <fstream> + +#include "hashmap.hh" +#include "sim_object.hh" + +#define SectorSize (512) + +/* + * Basic interface for accessing a disk image. + */ +class DiskImage : public SimObject +{ + protected: + bool initialized; + + public: + DiskImage(const std::string &name) : SimObject(name), initialized(false) {} + virtual ~DiskImage() {} + + virtual off_t size() const = 0; + + virtual off_t read(uint8_t *data, off_t offset) const = 0; + virtual off_t write(const uint8_t *data, off_t offset) = 0; +}; + +/* + * Specialization for accessing a raw disk image + */ +class RawDiskImage : public DiskImage +{ + protected: + mutable std::fstream stream; + std::string file; + bool readonly; + mutable off_t disk_size; + + public: + RawDiskImage(const std::string &name, const std::string &filename, + bool rd_only); + ~RawDiskImage(); + + void close(); + void open(const std::string &filename, bool rd_only = false); + + virtual off_t size() const; + + virtual off_t read(uint8_t *data, off_t offset) const; + virtual off_t write(const uint8_t *data, off_t offset); +}; + +/* + * Specialization for accessing a copy-on-write disk image layer. + * A copy-on-write(COW) layer must be stacked on top of another disk + * image layer this layer can be another CowDiskImage, or a + * RawDiskImage. + * + * This object is designed to provide a mechanism for persistant + * changes to a main disk image, or to provide a place for temporary + * changes to the image to take place that later may be thrown away. + */ +class CowDiskImage : public DiskImage +{ + public: + static const int VersionMajor; + static const int VersionMinor; + + protected: + struct Sector { + uint8_t data[SectorSize]; + }; + typedef m5::hash_map<uint64_t, Sector *> SectorTable; + + protected: + std::string filename; + DiskImage *child; + SectorTable *table; + + public: + CowDiskImage(const std::string &name, DiskImage *kid, int hash_size); + CowDiskImage(const std::string &name, DiskImage *kid, int hash_size, + const std::string &filename, bool read_only); + ~CowDiskImage(); + + void init(int hash_size); + bool open(); + void save(); + void writeback(); + + virtual off_t size() const; + + virtual off_t read(uint8_t *data, off_t offset) const; + virtual off_t write(const uint8_t *data, off_t offset); +}; + +#endif // __DISK_IMAGE_HH__ |