banan-os/kernel/kernel/Memory/Heap.cpp

96 lines
2.0 KiB
C++

#include <kernel/LockGuard.h>
#include <kernel/Memory/Heap.h>
#include <kernel/Memory/PageTable.h>
#include <kernel/multiboot.h>
namespace Kernel
{
static Heap* s_instance = nullptr;
void Heap::initialize()
{
ASSERT(s_instance == nullptr);
s_instance = new Heap;
ASSERT(s_instance);
s_instance->initialize_impl();
}
Heap& Heap::get()
{
ASSERT(s_instance);
return *s_instance;
}
void Heap::initialize_impl()
{
if (!(g_multiboot_info->flags & (1 << 6)))
Kernel::panic("Bootloader did not provide a memory map");
for (size_t i = 0; i < g_multiboot_info->mmap_length;)
{
multiboot_memory_map_t* mmmt = (multiboot_memory_map_t*)P2V(g_multiboot_info->mmap_addr + i);
if (mmmt->type == 1)
{
PhysicalRange range(mmmt->base_addr, mmmt->length);
if (range.usable_memory() > 0)
MUST(m_physical_ranges.push_back(range));
}
i += mmmt->size + sizeof(uint32_t);
}
size_t total = 0;
for (auto& range : m_physical_ranges)
{
size_t bytes = range.usable_memory();
dprintln("RAM {8H}->{8H} ({}.{} MB)", range.start(), range.end(), bytes / (1 << 20), bytes % (1 << 20) * 1000 / (1 << 20));
total += bytes;
}
dprintln("Total RAM {}.{} MB", total / (1 << 20), total % (1 << 20) * 1000 / (1 << 20));
}
paddr_t Heap::take_free_page()
{
LockGuard _(m_lock);
for (auto& range : m_physical_ranges)
if (paddr_t page = range.reserve_page())
return page;
return 0;
}
void Heap::release_page(paddr_t addr)
{
LockGuard _(m_lock);
for (auto& range : m_physical_ranges)
{
if (range.contains(addr))
{
range.release_page(addr);
return;
}
}
ASSERT_NOT_REACHED();
}
size_t Heap::used_pages() const
{
LockGuard _(m_lock);
size_t result = 0;
for (const auto& range : m_physical_ranges)
result += range.used_pages();
return result;
}
size_t Heap::free_pages() const
{
LockGuard _(m_lock);
size_t result = 0;
for (const auto& range : m_physical_ranges)
result += range.free_pages();
return result;
}
}