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-rw-r--r--src/kernel/mem/heap.basic.c136
1 files changed, 0 insertions, 136 deletions
diff --git a/src/kernel/mem/heap.basic.c b/src/kernel/mem/heap.basic.c
deleted file mode 100644
index d746deb..0000000
--- a/src/kernel/mem/heap.basic.c
+++ /dev/null
@@ -1,136 +0,0 @@
-#include "heap.basic.h"
-
-#include "paging.h"
-
-#include <lib/mutex.h>
-#include <core/sys.h>
-
-void heap_create(struct heap *heap, size_t start, size_t datasize, size_t maxdatasize) {
- uint32_t i;
- if (start & 0x0FFF) start = (start & 0xFFFFF000) + 0x1000;
-
- // Allocate frames
- for (i = start; i < start + datasize; i += 0x1000) {
- page_map(pagedir_getPage(kernel_pagedir, i, 1), frame_alloc(), 0, 0);
- }
-
- heap->start_addr = start;
- heap->end_addr = start + datasize;
- heap->max_end = start + maxdatasize;
-
- struct heap_header *first = (struct heap_header*)start;
- first->magic = HH_FREE_MAGIC;
- first->prev = first->next = first;
-
- heap->first = first;
- heap->first_free = first;
-
- heap->mutex = 0;
-}
-
-// ***** UTILITY FUNCTIONS *****
-
-#define BLK_SIZE(blk) (blk->next == blk ? ((size_t)heap->end_addr - (size_t)blk) : ((size_t)blk->next - (size_t)blk))
-#define BLK_FREE(blk) (blk->magic == HH_FREE_MAGIC)
-
-void blk_split(struct heap *heap, struct heap_header *hdr, size_t size) {
- ASSERT (size >= MIN_BLK_SIZE);
- ASSERT (BLK_SIZE(hdr) > size);
- ASSERT (BLK_SIZE(hdr) - size >= MIN_BLK_SIZE);
- ASSERT (BLK_FREE(hdr));
-
- struct heap_header *hdr_nxt = (struct heap_header*)((size_t)hdr + size);
- hdr_nxt->magic = HH_FREE_MAGIC;
- hdr_nxt->prev = hdr;
- if (hdr->next == hdr) {
- hdr_nxt->next = hdr_nxt;
- } else {
- hdr_nxt->next = hdr->next;
- hdr->next->prev = hdr_nxt;
- }
- hdr->next = hdr_nxt;
-}
-
-void blk_combine_next(struct heap *heap, struct heap_header *hdr) {
- ASSERT (hdr != hdr->next); // make sure we are not the last block
- ASSERT (hdr->magic == HH_FREE_MAGIC);
- ASSERT (hdr->next->magic == HH_FREE_MAGIC);
-
- struct heap_header *hdr_nxt = hdr->next;
- if (hdr_nxt->next == hdr_nxt) {
- hdr->next = hdr;
- } else {
- hdr->next = hdr_nxt->next;
- hdr_nxt->next->prev = hdr;
- }
-}
-
-// ***** Allocation/Freeing functions *****
-
-void *heap_alloc(struct heap *heap, size_t sz) {
- /* Algorithm :
- 1 Use heap->first_free to find first effectively free block, update heap->first_free
- 2 Find first free AND BIG ENOUGH block
- - If no block can be found, return 0 (no heap expand yet)
- 3 If that block is too big, split it in two
- 4 Mark that block as used and return it's address + sizeof(heap_header) */
- mutex_lock(&heap->mutex);
-
- sz += sizeof(struct heap_header);
- if (sz < MIN_BLK_SIZE) sz = MIN_BLK_SIZE;
- if (sz % 4 != 0) sz = sz + 4 - (sz % 4);
-
- // 1
- struct heap_header *it = heap->first_free;
- while (!BLK_FREE(it) && it != it->next) it = it->next;
- if (!BLK_FREE(it) && it == it->next) {
- mutex_unlock(&heap->mutex);
- return 0;
- }
- heap->first_free = it;
-
- // 2
- while (BLK_SIZE(it) < sz && it != it->next) it = it->next;
- if (BLK_SIZE(it) < sz) { // no block could be found
- mutex_unlock(&heap->mutex);
- return 0;
- }
-
- // 3
- if (BLK_SIZE(it) >= sz + MIN_BLK_SIZE) blk_split(heap, it, sz);
-
- // 4
- void *ret = (void*)((size_t)it + sizeof(struct heap_header));
- it->magic = HH_ALLOC_MAGIC;
-
- mutex_unlock(&heap->mutex);
- return ret;
-}
-
-void heap_free(struct heap *heap, void *ptr) {
- /* Algorithm :
- 1 Get block pointer to the block we are freeing
- 2 Mark that block as free
- 3 If block->next is free, combine_next(block)
- 4 If block->prev is free, block = block->prev; combine_next(block)
- 5 If block < heap->first_free; heap->first_free = block
- */
- mutex_lock(&heap->mutex);
-
- // 1
- struct heap_header *hdr = (struct heap_header*)((size_t)ptr - sizeof(struct heap_header));
- if (hdr->magic != HH_ALLOC_MAGIC) return;
- // 2
- hdr->magic = HH_FREE_MAGIC;
- // 3
- if (hdr->next != hdr && hdr->next->magic == HH_FREE_MAGIC) blk_combine_next(heap, hdr);
- // 4
- if (hdr->prev != hdr && hdr->prev->magic == HH_FREE_MAGIC) {
- hdr = hdr->prev;
- blk_combine_next(heap, hdr);
- }
- // 5
- if (hdr < heap->first_free) heap->first_free = hdr;
-
- mutex_unlock(&heap->mutex);
-}