49 lines
1.1 KiB
C++
49 lines
1.1 KiB
C++
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#include "blockdevice.hpp"
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namespace helos {
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class SlicedBlockDevice: public BlockDevice {
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public:
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SlicedBlockDevice(BlockDevice *backing, uint64_t off, uint64_t cnt)
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: backing(backing), off(off), cnt(cnt) {}
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public:
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virtual uint64_t BlockSize() const override {
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return backing->BlockSize();
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}
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uint64_t Size() const override {
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return cnt;
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}
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uint64_t SizeBytes() const override {
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return backing->BlockSize() * cnt;
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}
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::helos::Permission Permission() const override {
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return backing->Permission();
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}
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uint64_t ReadBlock(uint64_t blockOffset, void *data, uint64_t blockCount) const override {
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return backing->ReadBlock(blockOffset + off, data, blockCount);
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}
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uint64_t WriteBlock(uint64_t blockOffset, const void *data, uint64_t blockCount) override {
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return backing->WriteBlock(blockOffset + off, data, blockCount);
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}
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private:
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BlockDevice *backing;
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uint64_t off, cnt;
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};
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BlockDevice *BlockDevice::Slice(uint64_t blockOffset, uint64_t blockCount) {
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return new SlicedBlockDevice(this, blockOffset, blockCount);
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}
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} // namespace helos
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