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Kernel: MMU::get() is now MMU::kernel

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MMU is can now be locked with RecursiveSpinLock.

Scheduler now has get_current_tid() that works before the Scheduler
is initialized. This allows RecursiveSpinLock usage early on.
This commit is contained in:
Bananymous
2023-05-28 16:18:18 +03:00
parent a2ee543fa1
commit 869de7283f
11 changed files with 100 additions and 63 deletions
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103
kernel/arch/x86_64/MMU.cpp
View File

@@ -1,38 +1,41 @@
#include <BAN/Errors.h>
#include <kernel/Arch.h>
#include <kernel/LockGuard.h>
#include <kernel/Memory/kmalloc.h>
#include <kernel/Memory/MMU.h>
#define FLAGS_MASK (PAGE_SIZE - 1)
#define PAGE_MASK (~FLAGS_MASK)
#define CLEANUP_STRUCTURE(s) \
for (uint64_t i = 0; i < 512; i++) \
if (s[i] & Flags::Present) \
return; \
kfree(s)
#define CLEANUP_STRUCTURE(s) \
do { \
for (uint64_t i = 0; i < 512; i++) \
if ((s)[i] & Flags::Present) \
return; \
kfree(s); \
} while (false)
extern uint8_t g_kernel_end[];
namespace Kernel
{
static MMU* s_instance = nullptr;
static MMU* s_kernel = nullptr;
static MMU* s_current = nullptr;
void MMU::initialize()
{
ASSERT(s_instance == nullptr);
s_instance = new MMU();
ASSERT(s_instance);
s_instance->initialize_kernel();
s_instance->load();
ASSERT(s_kernel == nullptr);
s_kernel = new MMU();
ASSERT(s_kernel);
s_kernel->initialize_kernel();
s_kernel->load();
}
MMU& MMU::get()
MMU& MMU::kernel()
{
ASSERT(s_instance);
return *s_instance;
ASSERT(s_kernel);
return *s_kernel;
}
MMU& MMU::current()
@@ -61,13 +64,15 @@ namespace Kernel
MMU::MMU()
{
if (s_instance == nullptr)
if (s_kernel == nullptr)
return;
// Here we copy the s_instances paging structs since they are
// Here we copy the s_kernel paging structs since they are
// global for every process
uint64_t* global_pml4 = s_instance->m_highest_paging_struct;
LockGuard _(s_kernel->m_lock);
uint64_t* global_pml4 = s_kernel->m_highest_paging_struct;
uint64_t* pml4 = allocate_page_aligned_page();
for (uint32_t pml4e = 0; pml4e < 512; pml4e++)
@@ -136,6 +141,10 @@ namespace Kernel
void MMU::load()
{
uintptr_t rsp;
read_rsp(rsp);
ASSERT(!is_page_free(rsp & PAGE_MASK));
asm volatile("movq %0, %%cr3" :: "r"(m_highest_paging_struct));
s_current = this;
}
@@ -148,41 +157,39 @@ namespace Kernel
void MMU::identity_map_range(paddr_t address, size_t size, flags_t flags)
{
paddr_t s_page = address & PAGE_MASK;
paddr_t e_page = (address + size - 1) & PAGE_MASK;
for (paddr_t page = s_page; page <= e_page; page += PAGE_SIZE)
identity_map_page(page, flags);
LockGuard _(m_lock);
paddr_t s_page = address / PAGE_SIZE;
paddr_t e_page = (address + size - 1) / PAGE_SIZE;
for (paddr_t page = s_page; page <= e_page; page++)
identity_map_page(page * PAGE_SIZE, flags);
}
void MMU::unmap_page(vaddr_t address)
{
LockGuard _(m_lock);
ASSERT((address >> 48) == 0);
address &= PAGE_MASK;
if (is_page_free(address))
{
dwarnln("unmapping unmapped page {8H}", address);
return;
}
uint64_t pml4e = (address >> 39) & 0x1FF;
uint64_t pdpte = (address >> 30) & 0x1FF;
uint64_t pde = (address >> 21) & 0x1FF;
uint64_t pte = (address >> 12) & 0x1FF;
uint64_t* pml4 = m_highest_paging_struct;
if (!(pml4[pml4e] & Flags::Present))
return;
uint64_t* pdpt = (uint64_t*)(pml4[pml4e] & PAGE_MASK);
if (!(pdpt[pdpte] & Flags::Present))
return;
uint64_t* pd = (uint64_t*)(pdpt[pdpte] & PAGE_MASK);
if (!(pd[pde] & Flags::Present))
return;
uint64_t* pt = (uint64_t*)(pd[pde] & PAGE_MASK);
if (!(pt[pte] & Flags::Present))
return;
uint64_t* pd = (uint64_t*)(pdpt[pdpte] & PAGE_MASK);
uint64_t* pt = (uint64_t*)(pd[pde] & PAGE_MASK);
pt[pte] = 0;
CLEANUP_STRUCTURE(pt);
pd[pde] = 0;
CLEANUP_STRUCTURE(pd);
@@ -193,14 +200,18 @@ namespace Kernel
void MMU::unmap_range(vaddr_t address, size_t size)
{
vaddr_t s_page = address & PAGE_MASK;
vaddr_t e_page = (address + size - 1) & PAGE_MASK;
for (vaddr_t page = s_page; page <= e_page; page += PAGE_SIZE)
unmap_page(page);
LockGuard _(m_lock);
vaddr_t s_page = address / PAGE_SIZE;
vaddr_t e_page = (address + size - 1) / PAGE_SIZE;
for (vaddr_t page = s_page; page <= e_page; page++)
unmap_page(page * PAGE_SIZE);
}
void MMU::map_page_at(paddr_t paddr, vaddr_t vaddr, flags_t flags)
{
LockGuard _(m_lock);
ASSERT((paddr >> 48) == 0);
ASSERT((vaddr >> 48) == 0);
@@ -245,6 +256,8 @@ namespace Kernel
uint64_t MMU::get_page_data(vaddr_t address) const
{
LockGuard _(m_lock);
ASSERT((address >> 48) == 0);
ASSERT(address % PAGE_SIZE == 0);
@@ -284,6 +297,8 @@ namespace Kernel
vaddr_t MMU::get_free_page() const
{
LockGuard _(m_lock);
// Try to find free page that can be mapped without
// allocations (page table with unused entries)
vaddr_t* pml4 = m_highest_paging_struct;
@@ -332,6 +347,8 @@ namespace Kernel
vaddr_t MMU::get_free_contiguous_pages(size_t page_count) const
{
LockGuard _(m_lock);
for (vaddr_t address = PAGE_SIZE; !(address >> 48); address += PAGE_SIZE)
{
bool valid { true };
@@ -339,7 +356,7 @@ namespace Kernel
{
if (get_page_flags(address + page * PAGE_SIZE) & Flags::Present)
{
address += page;
address += page * PAGE_SIZE;
valid = false;
break;
}
@@ -359,8 +376,10 @@ namespace Kernel
bool MMU::is_range_free(vaddr_t start, size_t size) const
{
LockGuard _(m_lock);
vaddr_t first_page = start / PAGE_SIZE;
vaddr_t last_page = BAN::Math::div_round_up<vaddr_t>(start + size, PAGE_SIZE);
vaddr_t last_page = (start + size - 1) / PAGE_SIZE;
for (vaddr_t page = first_page; page <= last_page; page++)
if (!is_page_free(page * PAGE_SIZE))
return false;