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#include <DeviceManager/Time.ns.h>
template <typename T>
BlockCache<T>::BlockCache(T* dev) {
m_dev = dev;
m_count = 0;
}
template <typename T>
BlockCache<T>::~BlockCache() {
sync();
m_count = 0;
delete m_cache;
delete m_cacheInfo;
}
template <typename T>
void BlockCache<T>::sync() {
for (u32int i = 0; i < m_count; i++) {
if (m_cacheInfo[i].dirty) m_dev->writeBlocks(m_cacheInfo[i].id, 1, m_cache + (i * m_dev->blockSize()));
}
}
template <typename T>
void BlockCache<T>::init(u32int count) {
m_count = count;
m_cacheInfo = new cached_block_t[count];
for (u32int i = 0; i < m_count; i++) {
m_cacheInfo[i].id = 0;
m_cacheInfo[i].lastuse = 0;
m_cacheInfo[i].dirty = false;
}
m_cache = (u8int*)Mem::alloc(m_count * m_dev->blockSize());
}
template <typename T>
bool BlockCache<T>::setCache(u64int block, u8int* data, bool dirty) {
u32int best = 0;
for (u32int i = 0; i < m_count; i++) {
if (m_cacheInfo[i].id == block) {
best = i;
break;
}
if (m_cacheInfo[i].lastuse < m_cacheInfo[best].lastuse) best = i;
}
if (best >= m_count) return false;
if (m_cacheInfo[best].dirty && (m_cacheInfo[best].id != block or !dirty))
m_dev->writeBlocks(m_cacheInfo[best].id, 1, m_cache + (best * m_dev->blockSize()));
m_cacheInfo[best].id = block;
m_cacheInfo[best].lastuse = Time::uptime();
m_cacheInfo[best].dirty = dirty;
memcpy(m_cache + (best * m_dev->blockSize()), data, m_dev->blockSize());
return true;
}
template <typename T>
bool BlockCache<T>::getCache(u64int block, u8int* data) {
for (u32int i = 0; i < m_count; i++) {
if (m_cacheInfo[i].id == block && m_cacheInfo[i].lastuse != 0) {
m_cacheInfo[i].lastuse = Time::uptime();
memcpy(data, m_cache + (i * m_dev->blockSize()), m_dev->blockSize());
return true;
}
}
return false;
}
template <typename T>
bool BlockCache<T>::readBlocks(u64int startblock, u32int count, u8int* data) {
if (count == 1) {
if (getCache(startblock, data)) return true;
if (!m_dev->readBlocks(startblock, count, data)) return false;
setCache(startblock, data);
return true;
} else {
return m_dev->readBlocks(startblock, count, data);
}
}
template <typename T>
bool BlockCache<T>::writeBlocks(u64int startblock, u32int count, u8int* data) {
if (m_dev->readOnly()) return false;
if (count == 1) {
if (!setCache(startblock, data, true)) return m_dev->writeBlocks(startblock, count, data);
return true;
} else {
return m_dev->writeBlocks(startblock, count, data);
}
}
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