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Kernel: Don't allocate per-process PDPT from super pages either

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The default system is now down to 3 super pages allocated on boot. :^)
This commit is contained in:
Andreas Kling 2020-01-17 22:30:52 +01:00
parent ad1f79fb4a
commit 122c76d7fa
2 changed files with 10 additions and 6 deletions
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15
Kernel/VM/PageDirectory.cpp
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@ -45,17 +45,22 @@ PageDirectory::PageDirectory(Process& process, const RangeAllocator* parent_rang
, m_range_allocator(parent_range_allocator ? RangeAllocator(*parent_range_allocator) : RangeAllocator(VirtualAddress(userspace_range_base), kernelspace_range_base - userspace_range_base)) , m_range_allocator(parent_range_allocator ? RangeAllocator(*parent_range_allocator) : RangeAllocator(VirtualAddress(userspace_range_base), kernelspace_range_base - userspace_range_base))
{ {
// Set up a userspace page directory // Set up a userspace page directory
m_directory_table = MM.allocate_supervisor_physical_page(); m_directory_table = MM.allocate_user_physical_page();
m_directory_pages[0] = MM.allocate_user_physical_page(); m_directory_pages[0] = MM.allocate_user_physical_page();
m_directory_pages[1] = MM.allocate_user_physical_page(); m_directory_pages[1] = MM.allocate_user_physical_page();
m_directory_pages[2] = MM.allocate_user_physical_page(); m_directory_pages[2] = MM.allocate_user_physical_page();
// Share the top 1 GB of kernel-only mappings (>=3GB or >=0xc0000000) // Share the top 1 GB of kernel-only mappings (>=3GB or >=0xc0000000)
m_directory_pages[3] = MM.kernel_page_directory().m_directory_pages[3]; m_directory_pages[3] = MM.kernel_page_directory().m_directory_pages[3];
table().raw[0] = (u64)m_directory_pages[0]->paddr().as_ptr() | 1; {
table().raw[1] = (u64)m_directory_pages[1]->paddr().as_ptr() | 1; InterruptDisabler disabler;
table().raw[2] = (u64)m_directory_pages[2]->paddr().as_ptr() | 1; auto& table = *(PageDirectoryPointerTable*)MM.quickmap_page(*m_directory_table);
table().raw[3] = (u64)m_directory_pages[3]->paddr().as_ptr() | 1; table.raw[0] = (u64)m_directory_pages[0]->paddr().as_ptr() | 1;
table.raw[1] = (u64)m_directory_pages[1]->paddr().as_ptr() | 1;
table.raw[2] = (u64)m_directory_pages[2]->paddr().as_ptr() | 1;
table.raw[3] = (u64)m_directory_pages[3]->paddr().as_ptr() | 1;
MM.unquickmap_page();
}
// Clone bottom 8 MB of mappings from kernel_page_directory // Clone bottom 8 MB of mappings from kernel_page_directory
PageDirectoryEntry buffer[4]; PageDirectoryEntry buffer[4];

1
Kernel/VM/PageDirectory.h
View file

@ -22,7 +22,6 @@ public:
~PageDirectory(); ~PageDirectory();
u32 cr3() const { return m_directory_table->paddr().get(); } u32 cr3() const { return m_directory_table->paddr().get(); }
PageDirectoryPointerTable& table() { return *reinterpret_cast<PageDirectoryPointerTable*>(0xc0000000 + cr3()); }
RangeAllocator& range_allocator() { return m_range_allocator; } RangeAllocator& range_allocator() { return m_range_allocator; }