void free(void* p, heap* h)
{
// Exit gracefully for null pointers.
if (p == NULL)
return;
// Get the header and footer associated with this pointer.
header *head = (header*) ((u32int) p - sizeof (header));
footer *foot = (footer*) ((u32int) head + head->size - sizeof (footer));
// Sanity checks.
if(!(head->magic == HEAP_MAGIC && foot->magic == HEAP_MAGIC))
{
print_msg("Memory error\n");
return;
}
// Make us a hole.
head->is_hole = 1;
// Do we want to add this head into the 'free holes' index?
char do_add = 1;
// Unify left
// If the thing immediately to the left of us is a foot...
footer *test_foot = (footer*) ((u32int) head - sizeof (footer));
if (test_foot->magic == HEAP_MAGIC && test_foot->head->is_hole) {
u32int cache_size = head->size; // Cache our current size.
head = test_foot->head; // Rewrite our head with the new one.
foot->head = head; // Rewrite our foot to point to the new head.
head->size += cache_size; // Change the size.
do_add = 0; // Since this head is already in the index, we don't want to add it again.
}
// Unify right
// If the thing immediately to the right of us is a head...
header *test_head = (header*) ((u32int) foot + sizeof (footer));
if (test_head->magic == HEAP_MAGIC && test_head->is_hole) {
head->size += test_head->size; // Increase our size.
test_foot = (footer*) ((u32int) test_head + // Rewrite it's foot to point to our head.
test_head->size - sizeof (footer));
test_foot->head = head;
// Find and remove this head from the index.
u32int iterator = 0;
while ((iterator < h->index.size) && (lookup_ordered_array(iterator, &h->index) != (u32int) test_head))
iterator++;
// Make sure we actually found the item.
if(iterator >= h->index.size)
{
print_msg("Iterator behind heap size");
return;
}
// Remove it.
remove_ordered_array(iterator, &h->index);
}
if (do_add == 1)
insert_ordered_array((u32int) head, &h->index);
}
/* Remove the item /item/; if multiple exist, the first is deleted */
void remove_ordered_array_item(type_t item, ordered_array_t *array) {
for (uint32 i = 0; i < array->size; i++) {
if (lookup_ordered_array(i, array) == item) {
/* We found it! Now remove it: */
remove_ordered_array(i, array);
return;
}
}
}
void* alloc(u32int size, heap* h)
{
u32int new_size = size + sizeof (header) + sizeof (footer);
s32int iterator = find_smallest_hole(new_size, h);
if (iterator == -1) // If we didn't find a suitable hole
{
print_msg("No enough memory space\n");
return NULL;
}
header *orig_hole_header = (header *) lookup_ordered_array(iterator, &h->index);
u32int orig_hole_pos = (u32int) orig_hole_header;
u32int orig_hole_size = orig_hole_header->size;
// Here we work out if we should split the hole we found into two parts.
// Is the original hole size - requested hole size less than the overhead for adding a new hole?
if (orig_hole_size - new_size < sizeof (header) + sizeof (footer)) {
// Then just increase the requested size to the size of the hole we found.
size += orig_hole_size - new_size;
new_size = orig_hole_size;
}
remove_ordered_array(iterator, &h->index);
// we make sure all the header and footer attributes are correct, along with magic numbers
header *block_header = (header *) orig_hole_pos;
block_header->magic = HEAP_MAGIC;
block_header->is_hole = 0;
block_header->size = new_size;
footer *block_footer = (footer *) (orig_hole_pos + sizeof (header) + size);
block_footer->magic = HEAP_MAGIC;
block_footer->head = block_header;
// We may need to write a new hole after the allocated block.
// We do this only if the new hole would have positive size...
if (orig_hole_size - new_size > 0) {
header *hole_header = (header *) (orig_hole_pos + sizeof (header) + size + sizeof (footer));
hole_header->magic = HEAP_MAGIC;
hole_header->is_hole = 1;
hole_header->size = orig_hole_size - new_size;
footer *hole_footer = (footer *) ((u32int) hole_header + orig_hole_size - new_size - sizeof (footer));
if ((u32int) hole_footer < h->end_address) {
hole_footer->magic = HEAP_MAGIC;
hole_footer->head = hole_header;
}
// Put the new hole in the index;
insert_ordered_array((u32int) hole_header, &h->index);
}
return (void *) ((u32int) block_header + sizeof (header));
}
void free(void *p, heap_t *heap)
{
/*
* Exit gracefully for null pointers.
*/
if (!p)
return;
/*
* Get the header and footer associated with this
* pointer.
*/
header_t *header = (header_t *)((u32)p - sizeof(header_t));
footer_t *footer = (footer_t *)((u32)header + header->size - sizeof(footer_t));
/*
* Check the magic numbers of both the header
* and footer. If they do not match this is a bogus
* pointer passed.
*/
if (header->magic != HEAP_MAGIC)
return;
if (footer->magic != HEAP_MAGIC)
return;
/*
* Make us a hole.
*/
header->is_hole = 1;
/*
* Do we want to add this header into the "free holes"
* index?
*/
u8 do_add = 1;
/*
* Unify left. If the thing immediately to the left of us
* is a footer.
*/
footer_t *test_footer = (footer_t *)((u32)header - sizeof(footer_t));
if (test_footer->magic == HEAP_MAGIC &&
test_footer->header->is_hole) {
/*
* Cache our current size.
*/
u32 cache_size = header->size;
/*
* Rewrite our header with the new one.
*/
header = test_footer->header;
/*
* Rewrite our footer to point to the new
* header.
*/
footer->header = header;
/*
* Change the size of the new header.
*/
header->size += cache_size;
/*
* Since this header is already in the index, we dont
* want to add it again.
*/
do_add = 0;
}
/*
* Unify right. If the thing immediately to the right of us
* is a header.
*/
header_t *test_header = (header_t *)((u32)footer + sizeof(footer_t));
if (test_header->magic == HEAP_MAGIC &&
test_header->is_hole) {
/*
* Increase our current size.
*/
header->size += test_header->size;
/*
* Rewrite its footer to point to our header.
*/
test_footer = (footer_t *)((u32)test_header + test_header->size -
sizeof(footer_t));
footer = test_footer;
footer->header = header;
/*
* Find and remove test_header from the index.
*/
u32 i = 0;
while (i < heap->index.size &&
lookup_ordered_array(i, &heap->index) != (void *)test_header)
i++;
/*
* Make sure we actually found the item. Error
* debugging will be added later. For now just
* return.
*/
if (i == heap->index.size)
return;
/*
* Remove the pointer from the index list.
*/
remove_ordered_array(i, &heap->index);
}
/*
* If there was no unification, or there was a
* unify right, but not left, simply add the block of
* memory into the index list.
*/
if (do_add)
insert_ordered_array((void *)header, &heap->index);
}
void *alloc(u32 size, u8 page_align, heap_t *heap)
{
/*
* Make sure we take the size of the header/footer
* into account.
*/
u32 new_size = size + sizeof(header_t) + sizeof(footer_t);
/*
* Find the smallest hole that will fit
*/
s32 i = find_smallest_hole(new_size, page_align, heap);
if (i == -1) {
/*
* If we didnt find a suitable hole
*/
u32 old_length = heap->end_address - heap->start_address;
u32 old_end_address = heap->end_address;
expand(old_length + new_size, heap);
u32 new_length = heap->end_address - heap->start_address;
/*
* Find the endmost header. Not endmost in size, but in
* location.
*/
u32 i = 0, idx = -1, value = 0x0;
while (i < heap->index.size) {
u32 tmp = (u32)lookup_ordered_array(i, &heap->index);
if (tmp > value) {
value = tmp;
idx = i;
}
i++;
}
/*
* If we didnt find any headers, we need to add one
*/
if (idx == -1) {
header_t *header = (header_t *)old_end_address;
header->magic = HEAP_MAGIC;
header->size = new_length - old_length;
header->is_hole = 1;
footer_t *footer = (footer_t *)(old_end_address + header->size - sizeof(footer_t));
footer->magic = HEAP_MAGIC;
footer->header = header;
insert_ordered_array((void *)header, &heap->index);
}
else {
/*
* The last header needs adjusting
*/
header_t *header = lookup_ordered_array(idx, &heap->index);
header->size += new_length - old_length;
/* Rewrite the footer */
footer_t *footer = (footer_t *)((u32)header + header->size - sizeof(footer_t));
footer->header = header;
footer->magic = HEAP_MAGIC;
}
/*
* We now have enough space. Recurse call the function
* again.
*/
return alloc(size, page_align, heap);
}
header_t *orig_hole_header = (header_t *)lookup_ordered_array(i, &heap->index);
u32 orig_hole_pos = (u32)orig_hole_header;
u32 orig_hole_size = orig_hole_header->size;
if (orig_hole_size - new_size < sizeof(header_t) + sizeof(footer_t)) {
size += orig_hole_size - new_size;
new_size = orig_hole_size;
}
// If we need to page-align the data, do it now and make a new hole in front of our block.
if (page_align && orig_hole_pos&0xFFFFF000)
{
u32 new_location = orig_hole_pos + 0x1000 /* page size */ - (orig_hole_pos&0xFFF) - sizeof(header_t);
header_t *hole_header = (header_t *)orig_hole_pos;
hole_header->size = 0x1000 /* page size */ - (orig_hole_pos&0xFFF) - sizeof(header_t);
hole_header->magic = HEAP_MAGIC;
hole_header->is_hole = 1;
footer_t *hole_footer = (footer_t *) ( (u32)new_location - sizeof(footer_t) );
hole_footer->magic = HEAP_MAGIC;
hole_footer->header = hole_header;
orig_hole_pos = new_location;
orig_hole_size = orig_hole_size - hole_header->size;
}
else
{
// Else we don't need this hole any more, delete it from the index.
remove_ordered_array(i, &heap->index);
}
header_t *block_header = (header_t *)orig_hole_pos;
block_header->magic = HEAP_MAGIC;
block_header->is_hole = 0;
block_header->size = new_size;
footer_t *block_footer = (footer_t *)(orig_hole_pos + sizeof(header_t) + size);
block_footer->magic = HEAP_MAGIC;
block_footer->header = block_header;
/*
* We may need to write a new hole after the allocated block.
* We do this only if the new hole would have a positive size
*/
if (orig_hole_size - new_size > 0) {
header_t *hole_header = (header_t *)(orig_hole_pos + sizeof(header_t) + size + sizeof(footer_t));
hole_header->magic = HEAP_MAGIC;
hole_header->is_hole = 1;
hole_header->size = orig_hole_size - new_size;
footer_t *hole_footer = (footer_t *)((u32)hole_header + orig_hole_size - new_size - sizeof(footer_t));
hole_footer->magic = HEAP_MAGIC;
hole_footer->header = hole_header;
if ((u32)hole_footer < heap->end_address) {
hole_footer->magic = HEAP_MAGIC;
hole_footer->header = hole_header;
}
/*
* Put the new hole into the index.
*/
insert_ordered_array((void *)hole_header, &heap->index);
}
return (void *)((u32)block_header + sizeof(header_t));
}
void free(void *p, heap_t *heap) {
// Exit gracefully for null pointers.
if (p == 0) {
return;
}
// Get the header and footer associated with this pointer.
header_t *header = (header_t*) ((uint32_t) p - sizeof(header_t));
footer_t *footer = (footer_t*) ((uint32_t) header + header->size - sizeof(footer_t));
// Sanity checks.
ASSERT(header->magic == HEAP_MAGIC);
ASSERT(footer->magic == HEAP_MAGIC);
// Make us a hole.
header->is_hole = 1;
// Do we want to add this header into the 'free holes' index?
bool do_add = true;
// Unify left
// If the thing immediately to the left of us is a footer...
footer_t *test_footer = (footer_t*) ((uint32_t) header - sizeof(footer_t));
if(test_footer->magic == HEAP_MAGIC && test_footer->header->is_hole == 1) {
uint32_t cache_size = header->size; // Cache our current size.
header = test_footer->header; // Rewrite our header with the new one.
footer->header = header; // Rewrite our footer to point to the new header.
header->size += cache_size; // Change the size.
do_add = false; // Since this header is already in the index, we don't want to add it again.
}
// Unify right
// If the thing immediately to the right of us is a header...
header_t *test_header = (header_t*) ((uint32_t) footer + sizeof(footer_t));
if(test_header->magic == HEAP_MAGIC && test_header->is_hole) {
header->size += test_header->size; // Increase our size.
// Rewrite its footer to point to our header.
test_footer = (footer_t*) ((uint32_t) test_header + test_header->size - sizeof(footer_t));
footer = test_footer;
// Find and remove this header from the index.
uint32_t iterator = 0;
while((iterator < heap->index.size) && (lookup_ordered_array(iterator, &heap->index) != (void*)test_header)) {
iterator++;
}
// Make sure we actually found the item.
ASSERT(iterator < heap->index.size);
// Remove it.
remove_ordered_array(iterator, &heap->index);
}
/* // If the footer location is the end address, we can contract.
if ((uint32_t)footer+sizeof(footer_t) == heap->end_address) {
uint32_t old_length = heap->end_address-heap->start_address;
uint32_t new_length = contract((uint32_t) header - heap->start_address, heap);
// Check how big we will be after resizing.
if (header->size - (old_length-new_length) > 0) {
// We will still exist, so resize us.
header->size -= old_length-new_length;
footer = (footer_t*) ((uint32_t) header + header->size - sizeof(footer_t));
footer->magic = HEAP_MAGIC;
footer->header = header;
} else {
// We will no longer exist. Remove us from the index.
uint32_t iterator = 0;
while ((iterator < heap->index.size) && (lookup_ordered_array(iterator, &heap->index) != (void*) test_header)) {
iterator++;
}
// If we didn't find ourselves, we have nothing to remove.
if (iterator < heap->index.size) {
remove_ordered_array(iterator, &heap->index);
}
}
}*/
// If required, add us to the index.
if(do_add == true) {
insert_ordered_array((void*) header, &heap->index);
}
}
void *alloc(uint32_t size, bool page_align, heap_t *heap) {
// Make sure we take the size of header/footer into account.
uint32_t new_size = size + sizeof(header_t) + sizeof(footer_t);
// Find the smallest hole that will fit.
int32_t iterator = find_smallest_hole(new_size, page_align, heap);
if (iterator == -1) { // If we didn't find a suitable hole
// Save some previous data.
uint32_t old_length = heap->end_address - heap->start_address;
uint32_t old_end_address = heap->end_address;
// We need to allocate some more space.
expand(old_length+new_size, heap, size);
uint32_t new_length = heap->end_address-heap->start_address;
// Find the endmost header. (Not endmost in size, but in location).
iterator = 0;
// Vars to hold the index of, and value of, the endmost header found so far.
uint32_t idx = -1; uint32_t value = 0x0;
while(iterator < heap->index.size) {
uint32_t tmp = (uint32_t) lookup_ordered_array(iterator, &heap->index);
if(tmp > value) {
value = tmp;
idx = iterator;
}
iterator++;
}
// If we didn't find ANY headers, we need to add one.
if(idx == -1) {
header_t *header = (header_t *)old_end_address;
header->magic = HEAP_MAGIC;
header->size = new_length - old_length;
header->is_hole = 1;
footer_t *footer = (footer_t *) (old_end_address + header->size - sizeof(footer_t));
footer->magic = HEAP_MAGIC;
footer->header = header;
insert_ordered_array((void*) header, &heap->index);
} else {
// The last header needs adjusting.
header_t *header = lookup_ordered_array(idx, &heap->index);
header->size += new_length - old_length;
// Rewrite the footer.
footer_t *footer = (footer_t *) ((uint32_t) header + header->size - sizeof(footer_t));
footer->header = header;
footer->magic = HEAP_MAGIC;
}
// We now have enough space. Recurse, and call the function again.
return alloc(size, page_align, heap);
}
header_t *orig_hole_header = (header_t *) lookup_ordered_array(iterator, &heap->index);
uint32_t orig_hole_pos = (uint32_t) orig_hole_header;
uint32_t orig_hole_size = orig_hole_header->size;
// Here we work out if we should split the hole we found into two parts.
// Is the original hole size - requested hole size less than the overhead for adding a new hole?
if(orig_hole_size-new_size < sizeof(header_t) + sizeof(footer_t)) {
// Then just increase the requested size to the size of the hole we found.
size += orig_hole_size-new_size;
new_size = orig_hole_size;
}
// If we need to page-align the data, do it now and make a new hole in front of our block.
if(page_align && orig_hole_pos & 0xFFFFF000) {
uint32_t new_location = orig_hole_pos + 0x1000 /* page size */ - (orig_hole_pos&0xFFF) - sizeof(header_t);
header_t *hole_header = (header_t *)orig_hole_pos;
hole_header->size = 0x1000 /* page size */ - (orig_hole_pos&0xFFF) - sizeof(header_t);
hole_header->magic = HEAP_MAGIC;
hole_header->is_hole = 1;
footer_t *hole_footer = (footer_t *) ((uint32_t) new_location - sizeof(footer_t));
hole_footer->magic = HEAP_MAGIC;
hole_footer->header = hole_header;
orig_hole_pos = new_location;
orig_hole_size = orig_hole_size - hole_header->size;
} else {
// Else we don't need this hole any more, delete it from the index.
remove_ordered_array(iterator, &heap->index);
}
// Overwrite the original header...
header_t *block_header = (header_t *)orig_hole_pos;
block_header->magic = HEAP_MAGIC;
block_header->is_hole = 0;
block_header->size = new_size;
// ...And the footer
footer_t *block_footer = (footer_t *) (orig_hole_pos + sizeof(header_t) + size);
block_footer->magic = HEAP_MAGIC;
block_footer->header = block_header;
// We may need to write a new hole after the allocated block.
// We do this only if the new hole would have positive size...
if(orig_hole_size - new_size > 0) {
header_t *hole_header = (header_t *) (orig_hole_pos + sizeof(header_t) + size + sizeof(footer_t));
hole_header->magic = HEAP_MAGIC;
hole_header->is_hole = 1;
hole_header->size = orig_hole_size - new_size;
footer_t *hole_footer = (footer_t *) ((uint32_t) hole_header + orig_hole_size - new_size - sizeof(footer_t));
if ((uint32_t)hole_footer < heap->end_address) {
hole_footer->magic = HEAP_MAGIC;
hole_footer->header = hole_header;
}
// Put the new hole in the index;
insert_ordered_array((void*) hole_header, &heap->index);
}
// ...And we're done!
return (void *) ((uint32_t) block_header+sizeof(header_t));
}
void free(void *p, heap_t *heap)
{
if (!p)
return;
header_t *header = (header_t *)((u32int)p - sizeof(header_t));
footer_t *footer = (footer_t *)((u32int)header + header->size - sizeof(footer_t));
ASSERT(header->magic == HEAP_MAGIC);
ASSERT(footer->magic == HEAP_MAGIC);
header->is_hole = 1;
char do_add = 1;
// Unify left
footer_t *test_footer = (footer_t *)((u32int)header - sizeof(footer_t));
if (test_footer->magic == HEAP_MAGIC &&
test_footer->header->is_hole == 1)
{
u32int cache_size = header->size;
header = test_footer->header;
footer->header = header;
header->size += cache_size;
do_add = 0;
}
// Unify right
header_t *test_header = (header_t *)((u32int)footer + sizeof(footer_t));
if (test_header->magic == HEAP_MAGIC &&
test_header->is_hole)
{
header->size += test_header->size;
test_footer = (footer_t *)((u32int)test_header + test_header->size - sizeof(footer_t));
footer = test_footer;
u32int iterator = 0;
while ((iterator < heap->index.size) &&
(lookup_ordered_array(iterator, &heap->index) != (void *)test_header))
{
iterator++;
}
ASSERT(iterator < heap->index.size);
remove_ordered_array(iterator, &heap->index);
}
if ((u32int)footer + sizeof(footer_t) == heap->end_address)
{
u32int old_length = heap->end_address - heap->start_address;
u32int new_length = contract((u32int)header - heap->start_address, heap);
if (header->size - (old_length - new_length) > 0)
{
header->size -= old_length - new_length;
footer = (footer_t *)((u32int)header + header->size - sizeof(footer_t));
footer->magic = HEAP_MAGIC;
footer->header = header;
}
else
{
u32int iterator = 0;
while ((iterator < heap->index.size) &&
(lookup_ordered_array(iterator, &heap->index) != (void *)test_header))
{
iterator++;
}
if (iterator < heap->index.size)
remove_ordered_array(iterator, &heap->index);
}
}
if (do_add)
insert_ordered_array((void *)header, &heap->index);
}
void* alloc(u32int size, u8int page_align, heap_t *heap)
{
u32int new_size = size + sizeof(header_t) + sizeof(footer_t);
s32int iterator = find_smallest_hole(new_size, page_align, heap);
// no suitable hole found
if (iterator == -1)
{
u32int old_length = heap->end_address - heap->start_address;
u32int old_end_address = heap->end_address;
expand(old_length + new_size, heap);
u32int new_length = heap->end_address - heap->start_address;
iterator = 0;
u32int idx = -1; u32int value = 0x0;
while ((u32int)iterator < heap->index.size)
{
u32int tmp = (u32int)lookup_ordered_array(iterator, &heap->index);
if (tmp > value)
{
value = tmp;
idx = iterator;
}
iterator++;
}
if ((s32int)idx == -1)
{
header_t *header = (header_t *)old_end_address;
header->magic = HEAP_MAGIC;
header->size = new_length - old_length;
header->is_hole = 1;
footer_t *footer = (footer_t *)(old_end_address + header->size - sizeof(footer_t));
footer->magic = HEAP_MAGIC;
footer->header = header;
insert_ordered_array((void *)header, &heap->index);
}
else
{
header_t *header = lookup_ordered_array(idx, &heap->index);
header->size += new_length - old_length;
footer_t *footer = (footer_t *)((u32int)header + header->size - sizeof(footer_t));
footer->header = header;
footer->magic = HEAP_MAGIC;
}
return alloc(size, page_align, heap);
}
header_t *orig_hole_header = (header_t *)lookup_ordered_array(iterator, &heap->index);
u32int orig_hole_pos = (u32int)orig_hole_header;
u32int orig_hole_size = orig_hole_header->size;
if (orig_hole_size - new_size < sizeof(header_t) + sizeof(footer_t))
{
size += orig_hole_size - new_size;
new_size = orig_hole_size;
}
if (page_align && orig_hole_pos & ~0xfffff000)
{
u32int new_location = orig_hole_pos + 0x1000 - (orig_hole_pos & 0xfff) - sizeof(header_t);
header_t *hole_header = (header_t *)orig_hole_pos;
hole_header->size = 0x1000 - (orig_hole_pos & 0xfff) - sizeof(header_t);
hole_header->magic = HEAP_MAGIC;
hole_header->is_hole = 1;
footer_t *hole_footer = (footer_t *)((u32int)new_location - sizeof(footer_t));
hole_footer->magic = HEAP_MAGIC;
hole_footer->header = hole_header;
orig_hole_pos = new_location;
orig_hole_size -= hole_header->size;
}
else
{
remove_ordered_array(iterator, &heap->index);
}
header_t *block_header = (header_t *)orig_hole_pos;
block_header->magic = HEAP_MAGIC;
block_header->is_hole = 0;
block_header->size = new_size;
footer_t *block_footer = (footer_t *)(orig_hole_pos + sizeof(header_t) + size);
block_footer->magic = HEAP_MAGIC;
block_footer->header = block_header;
if (orig_hole_size - new_size > 0)
{
header_t *hole_header = (header_t *)(orig_hole_pos + sizeof(header_t) + sizeof(footer_t) + size);
hole_header->magic = HEAP_MAGIC;
hole_header->is_hole = 1;
hole_header->size = orig_hole_size - new_size;
footer_t *hole_footer = (footer_t *)((u32int)hole_header + orig_hole_size - new_size - sizeof(footer_t));
if ((u32int)hole_footer < heap->end_address)
{
hole_footer->magic = HEAP_MAGIC;
hole_footer->header = hole_header;
}
insert_ordered_array((void *)hole_header, &heap->index);
}
return (void *)((u32int)block_header + sizeof(header_t));
}
void vfree(void *p, struct vmem_heap* heap)
{
/* Exit gracefully for null pointers */
if (p == 0)
return;
/* Get the header and footer associated with this pointer */
struct vmem_header* header = (struct vmem_header*)((addr)p - sizeof(struct vmem_header));
struct vmem_footer* footer = (struct vmem_footer*)((addr)header + header->size - sizeof(struct vmem_footer));
/* Sanity checks */
ASSERT(header->magic == VMEM_MAGIC);
ASSERT(footer->magic == VMEM_MAGIC);
/* Make us a hole */
header->is_hole = 0;
/* Do we want to add this header to the free holes index */
char do_add = 1;
/* Unify left */
struct vmem_footer* test_footer = (struct vmem_footer*)((addr)header - sizeof(struct vmem_footer));
if (test_footer->magic == VMEM_MAGIC && test_footer->header->is_hole == 1)
{
addr cache_size = header->size; /* Cache our current size */
header = test_footer->header; /* Rewrite our header with the new one */
footer->header = header; /* Rewrite our footer to point to the new header */
header->size += cache_size; /* Change the size */
do_add = 0; /* Since this header is already in the index, we don't want to add it */
}
/* Unify right */
struct vmem_header* test_header = (struct vmem_header*)((addr)footer + sizeof(struct vmem_footer));
if (test_header->magic == VMEM_MAGIC && test_header->is_hole)
{
header->size += test_header->size; /* Increase our size */
test_footer = (struct vmem_footer*)((addr)test_header + test_header->size - sizeof(struct vmem_footer));
footer = test_footer;
/* Find and remove this kernel from the index */
unsigned int iterator = 0;
while ((iterator < heap->index.size) &&
(lookup_ordered_array(iterator, &heap->index) != (void*)test_header))
iterator++;
/* Make sure we actually found the item */
ASSERT(iterator < heap->index.size);
/* Remove it */
remove_ordered_array(iterator, &heap->index);
}
/* If the footer location is the end address, we can contract */
if ((addr)footer + sizeof(struct vmem_footer) == heap->end_address)
{
addr old_length = heap->end_address - heap->start_address;
addr new_length = contract((addr)header - heap->start_address, heap);
/* Check how big we will be after resizing */
if (header->size - (old_length - new_length) > 0)
{
/* We will still exist, so resize us */
header->size -= old_length - new_length;
footer = (struct vmem_footer*)((addr)header + header->size - sizeof(struct vmem_footer));
footer->magic = VMEM_MAGIC;
footer->header = header;
}
else
{
/* We will no longer exist, remove us from the index */
unsigned int iterator = 0;
while ((iterator < heap->index.size) &&
(lookup_ordered_array(iterator, &heap->index) != (void*)test_header))
iterator++;
/* If we didn't find ourselves, we have nothing to remove */
if (iterator < heap->index.size)
remove_ordered_array(iterator, &heap->index);
}
}
/* Add ourselves if we need to */
if (do_add == 1)
insert_ordered_array((void*)header, &heap->index);
}
void* vmalloc(addr size, unsigned char page_align, struct vmem_heap* heap)
{
/* Make sure we take the size of the header / footer into account */
addr new_size = size + sizeof(struct vmem_header) + sizeof(struct vmem_footer);
/* Find the smallest hole that will fit */
signed int iterator = find_smallest_hole(new_size, page_align, heap);
if (iterator == -1) /* If we didn't find a suitable hole */
{
/* Save some previous data */
addr old_length = heap->end_address - heap->start_address;
addr old_end_address = heap->end_address;
/* We need to allocate some more space */
expand(old_length + new_size, heap);
addr new_length = heap->end_address - heap->start_address;
/* Find the endmost header (not endmost in size, but in location) */
iterator = 0;
/* Vars to hold the index of, and value of, the endmost header found so far */
addr idx = -1; addr value = 0x0;
while (iterator < heap->index.size)
{
addr tmp = (addr)lookup_ordered_array(iterator, &heap->index);
if (tmp > value)
{
value = tmp;
idx = iterator;
}
iterator++;
}
/* If we didn't find any headers, we need to add one */
if (idx == -1)
{
struct vmem_header* header = (struct vmem_header*)old_end_address;
header->magic = VMEM_MAGIC;
header->size = new_length - old_length;
header->is_hole = 1;
struct vmem_footer* footer = (struct vmem_footer*)(old_end_address + header->size
- sizeof(struct vmem_footer));
footer->magic = VMEM_MAGIC;
footer->header = header;
insert_ordered_array((void*)header, &heap->index);
}
else
{
/* The last header needs adjusting */
struct vmem_header* header = lookup_ordered_array(idx, &heap->index);
header->size += new_length - old_length;
/* Rewrite the footer */
struct vmem_footer* footer = (struct vmem_footer*)((addr)header + header->size -
sizeof(struct vmem_footer));
footer->header = header;
footer->magic = VMEM_MAGIC;
}
}
struct vmem_header* orig_hole_header = (struct vmem_header*)lookup_ordered_array(iterator, &heap->index);
addr orig_hole_pos = (addr)orig_hole_header;
addr orig_hole_size = orig_hole_header->size;
/* Here we work out if we should split the hole we found into two parts.
* Is the original hole size - requested hole size less than the overhead for adding a new hole? */
if (orig_hole_size - new_size < sizeof(struct vmem_header) + sizeof(struct vmem_footer))
{
/* Then just increase the requested size to the size of the hole we found */
size += orig_hole_size - new_size;
new_size = orig_hole_size;
}
/* If we need to page-align the data, do it now and make a new hole in front of our block */
if (page_align && (orig_hole_pos & 0xFFFFF000))
{
addr new_location = orig_hole_pos + 0x1000 /* page size */ - (orig_hole_pos & 0xFFF) -
sizeof(struct vmem_header);
struct vmem_header* hole_header = (struct vmem_header*)orig_hole_pos;
hole_header->size = 0x1000 /* page size */ - (orig_hole_pos & 0xFFF) -
sizeof(struct vmem_header);
hole_header->magic = VMEM_MAGIC;
hole_header->is_hole = 1;
struct vmem_footer* hole_footer = (struct vmem_footer*)((addr)new_location - sizeof(struct vmem_footer));
hole_footer->magic = VMEM_MAGIC;
hole_footer->header = hole_header;
orig_hole_pos = new_location;
orig_hole_size = orig_hole_size - hole_header->size;
}
else
{
/* Else we don't need this hole any more, delete it from the index */
remove_ordered_array(iterator, &heap->index);
}
/* Overwrite the original header... */
struct vmem_header* block_header = (struct vmem_header*)orig_hole_pos;
block_header->magic = VMEM_MAGIC;
block_header->is_hole = 0;
block_header->size = new_size;
/* ... and the footer */
struct vmem_footer* block_footer = (struct vmem_footer*)(orig_hole_pos + sizeof(struct vmem_header) + size);
block_footer->magic = VMEM_MAGIC;
block_footer->header = block_header;
/* We may need to write a new hole after the allocated block.
* We do this only if the new hole would have positive size */
if (orig_hole_size - new_size > 0)
{
struct vmem_header* hole_header = (struct vmem_header*)(orig_hole_pos + sizeof(struct vmem_header) + size +
sizeof(struct vmem_footer));
hole_header->magic = VMEM_MAGIC;
hole_header->is_hole = 1;
hole_header->size = orig_hole_size - new_size;
struct vmem_footer* hole_footer = (struct vmem_footer*)((addr)hole_header + orig_hole_size - new_size -
sizeof(struct vmem_footer));
if ((addr)hole_footer < heap->end_address)
{
hole_footer->magic = VMEM_MAGIC;
hole_footer->header = hole_header;
}
/* Put the new hole in the array */
insert_ordered_array((void*)hole_header, &heap->index);
}
/* ... and we're done! */
return (void*)((addr)block_header + sizeof(struct vmem_header));
}