Kernel: Move PhysicalRange to its own file and add VirtualRange

This commit is contained in:
Bananymous 2023-05-28 16:21:45 +03:00
parent b847d7dfd5
commit e0479b291d
8 changed files with 312 additions and 150 deletions

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@ -29,6 +29,8 @@ set(KERNEL_SOURCES
kernel/Memory/GeneralAllocator.cpp
kernel/Memory/Heap.cpp
kernel/Memory/kmalloc.cpp
kernel/Memory/PhysicalRange.cpp
kernel/Memory/VirtualRange.cpp
kernel/Panic.cpp
kernel/PCI.cpp
kernel/PIC.cpp

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@ -3,50 +3,11 @@
#include <BAN/NoCopyMove.h>
#include <BAN/Vector.h>
#include <stdint.h>
#define PAGE_SIZE 4096
#include <kernel/Memory/PhysicalRange.h>
#include <kernel/SpinLock.h>
namespace Kernel
{
using vaddr_t = uintptr_t;
using paddr_t = uintptr_t;
class PhysicalRange
{
public:
PhysicalRange(paddr_t, size_t);
paddr_t reserve_page();
void release_page(paddr_t);
paddr_t start() const { return m_start; }
paddr_t end() const { return m_start + m_size; }
bool contains(paddr_t addr) const { return m_start <= addr && addr < m_start + m_size; }
size_t usable_memory() const { return m_reservable_pages * PAGE_SIZE; }
private:
struct node
{
node* next;
node* prev;
};
paddr_t page_address(const node*) const;
node* node_address(paddr_t) const;
private:
paddr_t m_start { 0 };
size_t m_size { 0 };
uint64_t m_total_pages { 0 };
uint64_t m_reservable_pages { 0 };
uint64_t m_list_pages { 0 };
node* m_free_list { nullptr };
node* m_used_list { nullptr };
};
class Heap
{
@ -65,7 +26,8 @@ namespace Kernel
void initialize_impl();
private:
BAN::Vector<PhysicalRange> m_physical_ranges;
BAN::Vector<PhysicalRange> m_physical_ranges;
SpinLock m_lock;
};
}

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@ -0,0 +1,46 @@
#pragma once
#include <kernel/Memory/Types.h>
#include <stddef.h>
#include <stdint.h>
namespace Kernel
{
class PhysicalRange
{
public:
PhysicalRange(paddr_t, size_t);
paddr_t reserve_page();
void release_page(paddr_t);
paddr_t start() const { return m_start; }
paddr_t end() const { return m_start + m_size; }
bool contains(paddr_t addr) const { return m_start <= addr && addr < m_start + m_size; }
size_t usable_memory() const { return m_reservable_pages * PAGE_SIZE; }
private:
struct node
{
node* next;
node* prev;
};
paddr_t page_address(const node*) const;
node* node_address(paddr_t) const;
private:
paddr_t m_start { 0 };
size_t m_size { 0 };
uint64_t m_total_pages { 0 };
uint64_t m_reservable_pages { 0 };
uint64_t m_list_pages { 0 };
node* m_free_list { nullptr };
node* m_used_list { nullptr };
};
}

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@ -0,0 +1,11 @@
#pragma once
#define PAGE_SIZE 4096
namespace Kernel
{
using vaddr_t = uintptr_t;
using paddr_t = uintptr_t;
}

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@ -0,0 +1,38 @@
#pragma once
#include <BAN/Vector.h>
#include <BAN/NoCopyMove.h>
#include <kernel/Memory/MMU.h>
#include <kernel/Memory/Types.h>
namespace Kernel
{
class VirtualRange
{
BAN_NON_COPYABLE(VirtualRange);
BAN_NON_MOVABLE(VirtualRange);
public:
static VirtualRange* create(MMU&, vaddr_t, size_t, uint8_t flags);
static VirtualRange* create_kmalloc(size_t);
~VirtualRange();
VirtualRange* clone(MMU& new_mmu);
vaddr_t vaddr() const { return m_vaddr; }
size_t size() const { return m_size; }
uint8_t flags() const { return m_flags; }
private:
VirtualRange(MMU&);
private:
MMU& m_mmu;
vaddr_t m_vaddr { 0 };
size_t m_size { 0 };
uint8_t m_flags { 0 };
BAN::Vector<paddr_t> m_physical_pages;
};
}

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@ -1,118 +1,11 @@
#include <kernel/LockGuard.h>
#include <kernel/Memory/Heap.h>
#include <kernel/Memory/MMU.h>
#include <kernel/multiboot.h>
extern uint8_t g_kernel_end[];
namespace Kernel
{
PhysicalRange::PhysicalRange(paddr_t start, size_t size)
{
// We can't use the memory ovelapping with kernel
if (start + size <= (paddr_t)g_kernel_end)
return;
// Align start to page boundary and after the kernel memory
m_start = BAN::Math::max(start, (paddr_t)g_kernel_end);
if (auto rem = m_start % PAGE_SIZE)
m_start += PAGE_SIZE - rem;
if (size <= m_start - start)
return;
// Align size to page boundary
m_size = size - (m_start - start);
if (auto rem = m_size % PAGE_SIZE)
m_size -= rem;
// We need atleast 2 pages
m_total_pages = m_size / PAGE_SIZE;
if (m_total_pages <= 1)
return;
// FIXME: if total pages is just over multiple of (PAGE_SIZE / sizeof(node)) we might make
// couple of pages unallocatable
m_list_pages = BAN::Math::div_round_up<uint64_t>(m_total_pages * sizeof(node), PAGE_SIZE);
m_reservable_pages = m_total_pages - m_list_pages;
MMU::get().identity_map_range(m_start, m_list_pages * PAGE_SIZE, MMU::Flags::ReadWrite | MMU::Flags::Present);
// Initialize page list so that every page points to the next one
node* page_list = (node*)m_start;
ASSERT((paddr_t)&page_list[m_reservable_pages - 1] <= m_start + m_size);
for (uint64_t i = 0; i < m_reservable_pages; i++)
page_list[i] = { page_list + i - 1, page_list + i + 1 };
page_list[ 0 ].next = nullptr;
page_list[m_reservable_pages - 1].prev = nullptr;
m_free_list = page_list;
m_used_list = nullptr;
}
paddr_t PhysicalRange::reserve_page()
{
if (m_free_list == nullptr)
return 0;
node* page = m_free_list;
ASSERT(page->next == nullptr);
// Detatch page from top of the free list
m_free_list = m_free_list->prev ? m_free_list->prev : nullptr;
if (m_free_list)
m_free_list->next = nullptr;
// Add page to used list
if (m_used_list)
m_used_list->next = page;
page->prev = m_used_list;
m_used_list = page;
return page_address(page);
}
void PhysicalRange::release_page(paddr_t page_address)
{
ASSERT(m_used_list);
node* page = node_address(page_address);
// Detach page from used list
if (page->prev)
page->prev->next = page->next;
if (page->next)
page->next->prev = page->prev;
if (m_used_list == page)
m_used_list = page->prev;
// Add page to the top of free list
page->prev = m_free_list;
page->next = nullptr;
if (m_free_list)
m_free_list->next = page;
m_free_list = page;
}
paddr_t PhysicalRange::page_address(const node* page) const
{
ASSERT((paddr_t)page <= m_start + m_reservable_pages * sizeof(node));
uint64_t page_index = page - (node*)m_start;
return m_start + (page_index + m_list_pages) * PAGE_SIZE;
}
PhysicalRange::node* PhysicalRange::node_address(paddr_t page_address) const
{
ASSERT(page_address % PAGE_SIZE == 0);
ASSERT(m_start + m_list_pages * PAGE_SIZE <= page_address && page_address < m_start + m_size);
uint64_t page_offset = page_address - (m_start + m_list_pages * PAGE_SIZE);
return (node*)m_start + page_offset / PAGE_SIZE;
}
static Heap* s_instance = nullptr;
void Heap::initialize()
@ -160,6 +53,7 @@ namespace Kernel
paddr_t Heap::take_free_page()
{
LockGuard _(m_lock);
for (auto& range : m_physical_ranges)
if (paddr_t page = range.reserve_page())
return page;
@ -168,6 +62,7 @@ namespace Kernel
void Heap::release_page(paddr_t addr)
{
LockGuard _(m_lock);
for (auto& range : m_physical_ranges)
{
if (range.contains(addr))

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@ -0,0 +1,115 @@
#include <BAN/Assert.h>
#include <BAN/Math.h>
#include <kernel/Memory/MMU.h>
#include <kernel/Memory/PhysicalRange.h>
extern uint8_t g_kernel_end[];
namespace Kernel
{
PhysicalRange::PhysicalRange(paddr_t start, size_t size)
{
// We can't use the memory ovelapping with kernel
if (start + size <= (paddr_t)g_kernel_end)
return;
// Align start to page boundary and after the kernel memory
m_start = BAN::Math::max(start, (paddr_t)g_kernel_end);
if (auto rem = m_start % PAGE_SIZE)
m_start += PAGE_SIZE - rem;
if (size <= m_start - start)
return;
// Align size to page boundary
m_size = size - (m_start - start);
if (auto rem = m_size % PAGE_SIZE)
m_size -= rem;
// We need atleast 2 pages
m_total_pages = m_size / PAGE_SIZE;
if (m_total_pages <= 1)
return;
// FIXME: if total pages is just over multiple of (PAGE_SIZE / sizeof(node)) we might make
// couple of pages unallocatable
m_list_pages = BAN::Math::div_round_up<uint64_t>(m_total_pages * sizeof(node), PAGE_SIZE);
m_reservable_pages = m_total_pages - m_list_pages;
MMU::kernel().identity_map_range(m_start, m_list_pages * PAGE_SIZE, MMU::Flags::ReadWrite | MMU::Flags::Present);
// Initialize page list so that every page points to the next one
node* page_list = (node*)m_start;
ASSERT((paddr_t)&page_list[m_reservable_pages - 1] <= m_start + m_size);
for (uint64_t i = 0; i < m_reservable_pages; i++)
page_list[i] = { page_list + i - 1, page_list + i + 1 };
page_list[ 0 ].next = nullptr;
page_list[m_reservable_pages - 1].prev = nullptr;
m_free_list = page_list;
m_used_list = nullptr;
}
paddr_t PhysicalRange::reserve_page()
{
if (m_free_list == nullptr)
return 0;
node* page = m_free_list;
ASSERT(page->next == nullptr);
// Detatch page from top of the free list
m_free_list = m_free_list->prev ? m_free_list->prev : nullptr;
if (m_free_list)
m_free_list->next = nullptr;
// Add page to used list
if (m_used_list)
m_used_list->next = page;
page->prev = m_used_list;
m_used_list = page;
return page_address(page);
}
void PhysicalRange::release_page(paddr_t page_address)
{
ASSERT(m_used_list);
node* page = node_address(page_address);
// Detach page from used list
if (page->prev)
page->prev->next = page->next;
if (page->next)
page->next->prev = page->prev;
if (m_used_list == page)
m_used_list = page->prev;
// Add page to the top of free list
page->prev = m_free_list;
page->next = nullptr;
if (m_free_list)
m_free_list->next = page;
m_free_list = page;
}
paddr_t PhysicalRange::page_address(const node* page) const
{
ASSERT((paddr_t)page <= m_start + m_reservable_pages * sizeof(node));
uint64_t page_index = page - (node*)m_start;
return m_start + (page_index + m_list_pages) * PAGE_SIZE;
}
PhysicalRange::node* PhysicalRange::node_address(paddr_t page_address) const
{
ASSERT(page_address % PAGE_SIZE == 0);
ASSERT(m_start + m_list_pages * PAGE_SIZE <= page_address && page_address < m_start + m_size);
uint64_t page_offset = page_address - (m_start + m_list_pages * PAGE_SIZE);
return (node*)m_start + page_offset / PAGE_SIZE;
}
}

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@ -0,0 +1,93 @@
#include <kernel/Memory/Heap.h>
#include <kernel/Memory/MMUScope.h>
#include <kernel/Memory/VirtualRange.h>
namespace Kernel
{
VirtualRange* VirtualRange::create(MMU& mmu, vaddr_t vaddr, size_t size, uint8_t flags)
{
ASSERT(size % PAGE_SIZE == 0);
ASSERT(vaddr % PAGE_SIZE == 0);
ASSERT(&mmu != &MMU::kernel());
VirtualRange* result = new VirtualRange(mmu);
ASSERT(result);
result->m_size = size;
result->m_flags = flags;
MUST(result->m_physical_pages.reserve(size / PAGE_SIZE));
mmu.lock();
if (vaddr == 0)
{
vaddr = mmu.get_free_contiguous_pages(size / PAGE_SIZE);
ASSERT(vaddr);
}
result->m_vaddr = vaddr;
ASSERT(mmu.is_range_free(vaddr, size));
for (size_t offset = 0; offset < size; offset += PAGE_SIZE)
{
paddr_t paddr = Heap::get().take_free_page();
ASSERT(paddr);
MUST(result->m_physical_pages.push_back(paddr));
mmu.map_page_at(paddr, vaddr + offset, flags);
}
mmu.unlock();
return result;
}
VirtualRange* VirtualRange::create_kmalloc(size_t size)
{
VirtualRange* result = new VirtualRange(MMU::kernel());
if (result == nullptr)
return nullptr;
result->m_size = size;
result->m_flags = MMU::Flags::ReadWrite | MMU::Flags::Present;
result->m_vaddr = (vaddr_t)kmalloc(size);
if (result->m_vaddr == 0)
{
delete result;
return nullptr;
}
return result;
}
VirtualRange::VirtualRange(MMU& mmu)
: m_mmu(mmu)
{ }
VirtualRange::~VirtualRange()
{
if (&m_mmu == &MMU::kernel())
{
kfree((void*)m_vaddr);
return;
}
m_mmu.unmap_range(vaddr(), size());
for (paddr_t page : m_physical_pages)
Heap::get().release_page(page);
}
VirtualRange* VirtualRange::clone(MMU& mmu)
{
VirtualRange* result = create(mmu, vaddr(), size(), flags());
MMUScope _(m_mmu);
ASSERT(m_mmu.is_page_free(0));
for (size_t i = 0; i < result->m_physical_pages.size(); i++)
{
m_mmu.map_page_at(result->m_physical_pages[i], 0, MMU::Flags::ReadWrite | MMU::Flags::Present);
memcpy((void*)0, (void*)(vaddr() + i * PAGE_SIZE), PAGE_SIZE);
}
m_mmu.unmap_page(0);
return result;
}
}