PastaBoy12345/vystem-b
2
0
Fork 0
forked from lolo859/vystem
Code Pull Requests Activity

Vystem 0.2

Browse Source
This commit is contained in:
lolo859
2026-05-27 19:34:54 +02:00
parent a43c08b893
commit d238606b75
372 changed files with 51320 additions and 83217 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
docs/shelter/ptp.md
View File

@@ -2,7 +2,7 @@
## Introduction
In order to easely manage pages that are used for pages tables (PT), the Vystem project use pages tables pool (PTP). For details about mapping the PTP inside the kernel virtual memory space, please see [boot contract docs](bootcontract.md).
In order to easily manage pages that are used for pages tables (PT), the Vystem project use pages tables pool (PTP). For details about mapping the PTP inside the kernel virtual memory space, please see [boot contract docs](bootcontract.md).
## Overview
@@ -20,4 +20,4 @@ PTP, when created from the bootloader, are mapped within themself read-write and
The purpose of any PTP is to have a reserved amount of pages to permit the quick allocation of single page to allow any mapping. There is two kinds of allocator, depending on the needs of the situation:
- bumb/counter allocator: here, we simply increment a counter that represent an index inside the pages range of the PTP, allowing for very quick PTP initialization. Intended for PTP creation and mapping without unmapping by the program creating the PTP. This is the kind of allocator used into the Blastproof bootloader
- bitmap allocator: a bitmap for storing which pages of the pages range is allocated or not. Intended when heavy unmapping is made, to free pages more easely. This is the allocator used in the Shelter Kernel. It can be initialized from the counter value, passed by the bootloader for example. For the moment, automatic pages freeing from the page table isn't implemented.
- bitmap allocator: a bitmap for storing which pages of the pages range is allocated or not. Intended when heavy unmapping is made, to free pages more easily. This is the allocator used in the Shelter Kernel. It can be initialized from the counter value, passed by the bootloader for example. For the moment, automatic pages freeing from the page table isn't implemented.