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Kernel: Change PageTable API

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Getting free pages not reserves them, so you don't have to hold
the page table lock :)
This commit is contained in:
Bananymous
2023-08-02 22:09:14 +03:00
parent 64ad752e73
commit 3139391e06
12 changed files with 208 additions and 109 deletions
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4
kernel/kernel/Memory/FixedWidthAllocator.cpp
View File

@@ -212,7 +212,9 @@ namespace Kernel
paddr_t page_paddr = Heap::get().take_free_page();
ASSERT(page_paddr);
page_vaddr = m_page_table.get_free_page();
page_vaddr = m_page_table.reserve_free_page(0x300000);
ASSERT(page_vaddr);
m_page_table.map_page_at(page_paddr, page_vaddr, PageTable::Flags::UserSupervisor | PageTable::Flags::ReadWrite | PageTable::Flags::Present);
}

2
kernel/kernel/Memory/GeneralAllocator.cpp
View File

@@ -44,7 +44,7 @@ namespace Kernel
m_page_table.lock();
allocation.address = m_page_table.get_free_contiguous_pages(needed_pages, m_first_vaddr);
allocation.address = m_page_table.reserve_free_contiguous_pages(needed_pages, m_first_vaddr);
ASSERT(allocation.address);
for (size_t i = 0; i < needed_pages; i++)

6
kernel/kernel/Memory/PhysicalRange.cpp
View File

@@ -40,12 +40,10 @@ namespace Kernel
m_used_pages = 0;
m_free_pages = m_reservable_pages;
PageTable::kernel().lock();
m_vaddr = PageTable::kernel().get_free_contiguous_pages(m_list_pages, ((vaddr_t)g_kernel_end + PAGE_SIZE - 1) & PAGE_ADDR_MASK);
m_vaddr = PageTable::kernel().reserve_free_contiguous_pages(m_list_pages, KERNEL_OFFSET);
ASSERT(m_vaddr);
PageTable::kernel().map_range_at(m_paddr, m_vaddr, m_list_pages * PAGE_SIZE, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
PageTable::kernel().unlock();
// Initialize page list so that every page points to the next one
node* page_list = (node*)m_vaddr;

79
kernel/kernel/Memory/VirtualRange.cpp
View File

@@ -1,14 +1,16 @@
#include <BAN/ScopeGuard.h>
#include <kernel/LockGuard.h>
#include <kernel/Memory/Heap.h>
#include <kernel/Memory/VirtualRange.h>
namespace Kernel
{
BAN::ErrorOr<BAN::UniqPtr<VirtualRange>> VirtualRange::create(PageTable& page_table, vaddr_t vaddr, size_t size, uint8_t flags)
BAN::ErrorOr<BAN::UniqPtr<VirtualRange>> VirtualRange::create_to_vaddr(PageTable& page_table, vaddr_t vaddr, size_t size, uint8_t flags)
{
ASSERT(size % PAGE_SIZE == 0);
ASSERT(vaddr % PAGE_SIZE == 0);
ASSERT(vaddr > 0);
VirtualRange* result_ptr = new VirtualRange(page_table);
if (result_ptr == nullptr)
@@ -16,25 +18,13 @@ namespace Kernel
auto result = BAN::UniqPtr<VirtualRange>::adopt(result_ptr);
result->m_kmalloc = false;
result->m_vaddr = vaddr;
result->m_size = size;
result->m_flags = flags;
TRY(result->m_physical_pages.reserve(size / PAGE_SIZE));
page_table.lock();
if (vaddr == 0)
{
vaddr = page_table.get_free_contiguous_pages(size / PAGE_SIZE, 0x300000);
if (vaddr == 0)
{
derrorln("out of virtual memory");
return BAN::Error::from_errno(ENOMEM);
}
}
result->m_vaddr = vaddr;
ASSERT(page_table.is_range_free(vaddr, size));
ASSERT(page_table.reserve_range(vaddr, size));
BAN::ScopeGuard unmapper([vaddr, size, &page_table] { page_table.unmap_range(vaddr, size); });
TRY(result->m_physical_pages.reserve(size / PAGE_SIZE));
for (size_t offset = 0; offset < size; offset += PAGE_SIZE)
@@ -50,7 +40,60 @@ namespace Kernel
page_table.map_page_at(paddr, vaddr + offset, flags);
}
page_table.unlock();
unmapper.disable();
return result;
}
BAN::ErrorOr<BAN::UniqPtr<VirtualRange>> VirtualRange::create_to_vaddr_range(PageTable& page_table, vaddr_t vaddr_start, vaddr_t vaddr_end, size_t size, uint8_t flags)
{
ASSERT(size % PAGE_SIZE == 0);
ASSERT(vaddr_start > 0);
// Align vaddr range to page boundaries
if (size_t rem = vaddr_start % PAGE_SIZE)
vaddr_start += PAGE_SIZE - rem;
if (size_t rem = vaddr_end % PAGE_SIZE)
vaddr_end -= rem;
ASSERT(vaddr_start < vaddr_end);
ASSERT(vaddr_end - vaddr_start + 1 >= size / PAGE_SIZE);
VirtualRange* result_ptr = new VirtualRange(page_table);
if (result_ptr == nullptr)
return BAN::Error::from_errno(ENOMEM);
auto result = BAN::UniqPtr<VirtualRange>::adopt(result_ptr);
result->m_kmalloc = false;
result->m_size = size;
result->m_flags = flags;
TRY(result->m_physical_pages.reserve(size / PAGE_SIZE));
vaddr_t vaddr = page_table.reserve_free_contiguous_pages(size / PAGE_SIZE, vaddr_start, vaddr_end);
if (vaddr == 0)
return BAN::Error::from_errno(ENOMEM);
result->m_vaddr = vaddr;
BAN::ScopeGuard unmapper([vaddr, size, &page_table] { page_table.unmap_range(vaddr, size); });
if (vaddr + size > vaddr_end)
return BAN::Error::from_errno(ENOMEM);
result->m_vaddr = vaddr;
TRY(result->m_physical_pages.reserve(size / PAGE_SIZE));
for (size_t offset = 0; offset < size; offset += PAGE_SIZE)
{
paddr_t paddr = Heap::get().take_free_page();
if (paddr == 0)
{
for (paddr_t release : result->m_physical_pages)
Heap::get().release_page(release);
return BAN::Error::from_errno(ENOMEM);
}
MUST(result->m_physical_pages.push_back(paddr));
page_table.map_page_at(paddr, vaddr + offset, flags);
}
unmapper.disable();
return result;
}
@@ -92,7 +135,7 @@ namespace Kernel
BAN::ErrorOr<BAN::UniqPtr<VirtualRange>> VirtualRange::clone(PageTable& page_table)
{
auto result = TRY(create(page_table, vaddr(), size(), flags()));
auto result = TRY(create_to_vaddr(page_table, vaddr(), size(), flags()));
m_page_table.lock();