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Optimization for ramdisk

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Do not allocate pages on read
This commit is contained in:
Baptiste Wicht 2016-08-11 18:54:58 +02:00
parent 5516b25562
commit 0a5128dfa7
1 changed files with 6 additions and 5 deletions
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11
kernel/src/ramdisk.cpp
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@ -51,15 +51,16 @@ size_t ramdisk::ramdisk_driver::read(void* data, char* destination, size_t count
auto page = offset / paging::PAGE_SIZE;
auto page_offset = offset % paging::PAGE_SIZE;
auto to_read = std::min(paging::PAGE_SIZE, count - read) - page_offset;
// If the page is not allocated, we simply consider it full of zero
if(!disk->allocated[page]){
disk->allocated[page] = new char[paging::PAGE_SIZE];
std::fill_n(disk->allocated[page], paging::PAGE_SIZE, 0);
std::fill_n(destination, to_read, 0);
} else {
std::copy_n(destination, disk->allocated[page] + page_offset, to_read);
}
auto to_read = std::min(paging::PAGE_SIZE, count - read) - page_offset;
std::copy_n(destination, disk->allocated[page] + page_offset, to_read);
read += to_read;
offset += to_read;
}