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+/*
+ * 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__