diff options
Diffstat (limited to 'Source/Kernel/MemoryManager/Heap.class.cpp')
-rw-r--r-- | Source/Kernel/MemoryManager/Heap.class.cpp | 212 |
1 files changed, 0 insertions, 212 deletions
diff --git a/Source/Kernel/MemoryManager/Heap.class.cpp b/Source/Kernel/MemoryManager/Heap.class.cpp deleted file mode 100644 index 365b4f0..0000000 --- a/Source/Kernel/MemoryManager/Heap.class.cpp +++ /dev/null @@ -1,212 +0,0 @@ -#include "Heap.class.h" -#include <MemoryManager/PageDirectory.class.h> - -Heap::Heap() : m_mutex(MUTEX_FALSE) { - m_usable = false; - m_index.data = 0; - m_index.size = 0; -} - -Heap::~Heap() { - //TODO (optionnal) : free pages. -} - -void Heap::create(u32int start, u32int size, u32int idxsize, PageDirectory* pagedir, bool user, bool rw) { - if (m_usable) return; - - if (start & 0x0FFF) start = (start & 0xFFFFF000) + 0x1000; - if (size & 0x0FFF) size = (size & 0xFFFFF000) + 0x1000; - m_start = start + idxsize; //m_start is start of real data, start is start of index. - m_end = start + size; - - m_pagedir = pagedir; - m_user = user; - m_rw = rw; - - //Allocate frames for heap - for (u32int i = start ; i < m_end; i += 0x1000) { - m_pagedir->allocFrame(i, m_user, m_rw); - } - m_pagedir->switchTo(); - - m_index.data = (heap_header_t **)start; //Set index start. start == start of all heap - m_index.size = 0; - - heap_header_t *hole = (heap_header_t*) m_start; //m_start == start of data - hole->size = (m_end - m_start); - hole->magic = HEAP_MAGIC; - hole->is_hole = true; - - heap_footer_t *hole_footer = (heap_footer_t*) (m_end - sizeof(heap_footer_t)); - hole_footer->header = hole; - hole_footer->magic = HEAP_MAGIC; - - insertIntoIndex(hole); - - m_usable = true; - m_free = (m_end - m_start); - - m_mutex.unlock(); -} - -void Heap::expand(u32int quantity) { - if (quantity & 0x00000FFF) - quantity = (quantity & 0xFFFFF000) + 0x1000; - - u32int newEnd = m_end + quantity; - - for (u32int i = m_end; i < newEnd; i++) { - m_pagedir->allocFrame(i, m_user, m_rw); - } - - heap_footer_t *last_footer = (heap_footer_t*) (m_end - sizeof(heap_footer_t)); - heap_header_t *last_header = last_footer->header; - if (last_header->is_hole) { //Last block of heap is a hole, update its size - removeFromIndex(last_header); - last_header->size += quantity; - - last_footer = (heap_footer_t*) (newEnd - sizeof(heap_footer_t)); - - last_footer->magic = HEAP_MAGIC; - last_footer->header = last_header; - - insertIntoIndex(last_header); - } else { //Last block is not a hole. Just add a new hole at the end - last_header = (heap_header_t*)m_end; - last_footer = (heap_footer_t*) (newEnd - sizeof(heap_footer_t)); - - last_header->is_hole = true; - last_header->magic = HEAP_MAGIC; - last_header->size = quantity; - - last_footer->magic = HEAP_MAGIC; - last_footer->header = last_header; - - insertIntoIndex(last_header); - } - - m_end = newEnd; - m_free += quantity; -} - -void Heap::contract() { //Automatically work out how much we can contract - heap_footer_t *last_footer = (heap_footer_t*) (m_end - sizeof(heap_footer_t)); - heap_header_t *last_header = last_footer->header; - if (last_header->is_hole == false) return; //We need a hole at end of heap - - u32int quantity = 0; - while ((m_end - m_start) - quantity > HEAP_MIN_SIZE and - (last_header->size - quantity) > 0x1000) //Always keep at least 0x1000 free at end - quantity += 0x1000; - if (quantity == 0) return; - - u32int newEnd = m_end - quantity; - m_free -= quantity; - - removeFromIndex(last_header); - last_header->size -= quantity; - last_footer = (heap_footer_t*)((u32int)last_footer - quantity); - last_footer->magic = HEAP_MAGIC; - last_footer->header = last_header; - insertIntoIndex(last_header); - - for (u32int i = newEnd; i < m_end; i += 0x1000) { - m_pagedir->freeFrame(i); - } - - m_end = newEnd; -} - -void *Heap::alloc(u32int sz, bool no_expand) { - m_mutex.waitLock(); - - u32int newsize = sz + sizeof(heap_header_t) + sizeof(heap_footer_t); - u32int iterator = 0; - while (iterator < m_index.size) { - if (m_index.data[iterator]->size >= newsize) break; - iterator++; - } - if (iterator == m_index.size) { //No hole is big enough - if (no_expand) { - m_mutex.unlock(); - return 0; - } - expand((sz & 0xFFFFF000) + 0x1000); - m_mutex.unlock(); - return alloc(sz, true); //Recurse call - } - - heap_header_t *loc = m_index.data[iterator]; - heap_footer_t *footer = (heap_footer_t*)((u32int)loc + loc->size - sizeof(heap_footer_t)); - loc->is_hole = false; //Update current header - - removeFromIndex(loc); - - //Here we create a new hole after currently allocated block, but only if we have enough space. If we don't, we simply allocate a bigger block so that we don't loose space - if (loc->size > (newsize + sizeof(heap_header_t) + sizeof(heap_footer_t))) { - loc->size = newsize; //Update header for return block - - heap_footer_t *newfooter = (heap_footer_t*)((u32int)loc + newsize - sizeof(heap_footer_t)); //Write footer for return block - newfooter->header = loc; - newfooter->magic = HEAP_MAGIC; - - heap_header_t *nextloc = (heap_header_t*)((u32int)loc + newsize); //Write header for new hole - nextloc->is_hole = true; - nextloc->magic = HEAP_MAGIC; - nextloc->size = ((u32int)footer - (u32int)nextloc + sizeof(heap_footer_t)); - - footer->header = nextloc; //Write footer for new hole - footer->magic = HEAP_MAGIC; - - insertIntoIndex(nextloc); - } - - m_free -= loc->size; - - m_mutex.unlock(); - - return (void*)((u32int)loc + sizeof(heap_header_t)); -} - -void Heap::free(void *ptr) { - if (ptr == 0) return; - - heap_header_t *header = (heap_header_t*) ((u32int)ptr - sizeof(heap_header_t)); - heap_footer_t *footer = (heap_footer_t*)((u32int)header + header->size - sizeof(heap_footer_t)); - if (header->magic != HEAP_MAGIC or footer->magic != HEAP_MAGIC) return; - - m_mutex.waitLock(); - - m_free += header->size; - - //Unify left - heap_footer_t *prev_footer = (heap_footer_t*)((u32int)header - sizeof(heap_footer_t)); - if (prev_footer->magic == HEAP_MAGIC && prev_footer->header->is_hole) { - header = prev_footer->header; - removeFromIndex(header); - - footer->header = header; - header->size = ((u32int)footer - (u32int)header + sizeof(heap_footer_t)); - } - - //Unify right - heap_header_t *next_header = (heap_header_t*)((u32int)footer + sizeof(heap_footer_t)); - if (next_header->magic == HEAP_MAGIC && next_header->is_hole) { - removeFromIndex(next_header); - footer = (heap_footer_t*)((u32int)footer + next_header->size); - - footer->header = header; - header->size = ((u32int)footer - (u32int)header + sizeof(heap_footer_t)); - } - - header->is_hole = true; - - insertIntoIndex(header); - - if ((u32int)footer == (m_end - sizeof(heap_footer_t)) and - header->size >= 0x2000 and (m_end - m_start > HEAP_MIN_SIZE)) { - contract(); - } - - m_mutex.unlock(); -} |