RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-05-16 19:05:08 +00:00
Code Issues Activity Actions

Kernel: Stop allocating page tables from the super pages pool

Browse source 
We now use the regular "user" physical pages for on-demand page table
allocations. This was by far the biggest source of super physical page
exhaustion, so that bug should be a thing of the past now. :^)

We still have super pages, but they are barely used. They remain useful
for code that requires memory with a low physical address.

Fixes #1000.
This commit is contained in:
Andreas Kling 2020-01-17 22:18:56 +01:00
parent f71fc88393
commit ad1f79fb4a
3 changed files with 19 additions and 34 deletions
Download patch file Download diff file Expand all files Collapse all files

6
Kernel/VM/PageDirectory.cpp
View file

@ -46,9 +46,9 @@ PageDirectory::PageDirectory(Process& process, const RangeAllocator* parent_rang
{
// Set up a userspace page directory
m_directory_table = MM.allocate_supervisor_physical_page();
m_directory_pages[0] = MM.allocate_supervisor_physical_page();
m_directory_pages[1] = MM.allocate_supervisor_physical_page();
m_directory_pages[2] = MM.allocate_supervisor_physical_page();
m_directory_pages[0] = MM.allocate_user_physical_page();
m_directory_pages[1] = 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)
m_directory_pages[3] = MM.kernel_page_directory().m_directory_pages[3];