mirror of
				https://github.com/RGBCube/serenity
				synced 2025-10-31 21:12:43 +00:00 
			
		
		
		
	 cd5faf4e42
			
		
	
	
		cd5faf4e42
		
	
	
	
	
		
			
			...and also RangeAllocator => VirtualRangeAllocator. This clarifies that the ranges we're dealing with are *virtual* memory ranges and not anything else.
		
			
				
	
	
		
			56 lines
		
	
	
	
		
			1.5 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			56 lines
		
	
	
	
		
			1.5 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| /*
 | |
|  * Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
 | |
|  * Copyright (c) 2021, Leon Albrecht <leon2002.la@gmail.com>
 | |
|  *
 | |
|  * SPDX-License-Identifier: BSD-2-Clause
 | |
|  */
 | |
| 
 | |
| #include <AK/Vector.h>
 | |
| #include <Kernel/Memory/MemoryManager.h>
 | |
| #include <Kernel/Memory/VirtualRange.h>
 | |
| #include <LibC/limits.h>
 | |
| 
 | |
| namespace Kernel::Memory {
 | |
| 
 | |
| Vector<VirtualRange, 2> VirtualRange::carve(VirtualRange const& taken) const
 | |
| {
 | |
|     VERIFY((taken.size() % PAGE_SIZE) == 0);
 | |
| 
 | |
|     Vector<VirtualRange, 2> parts;
 | |
|     if (taken == *this)
 | |
|         return {};
 | |
|     if (taken.base() > base())
 | |
|         parts.append({ base(), taken.base().get() - base().get() });
 | |
|     if (taken.end() < end())
 | |
|         parts.append({ taken.end(), end().get() - taken.end().get() });
 | |
|     return parts;
 | |
| }
 | |
| VirtualRange VirtualRange::intersect(VirtualRange const& other) const
 | |
| {
 | |
|     if (*this == other) {
 | |
|         return *this;
 | |
|     }
 | |
|     auto new_base = max(base(), other.base());
 | |
|     auto new_end = min(end(), other.end());
 | |
|     VERIFY(new_base < new_end);
 | |
|     return VirtualRange(new_base, (new_end - new_base).get());
 | |
| }
 | |
| 
 | |
| KResultOr<VirtualRange> VirtualRange::expand_to_page_boundaries(FlatPtr address, size_t size)
 | |
| {
 | |
|     if (page_round_up_would_wrap(size))
 | |
|         return EINVAL;
 | |
| 
 | |
|     if ((address + size) < address)
 | |
|         return EINVAL;
 | |
| 
 | |
|     if (page_round_up_would_wrap(address + size))
 | |
|         return EINVAL;
 | |
| 
 | |
|     auto base = VirtualAddress { address }.page_base();
 | |
|     auto end = page_round_up(address + size);
 | |
| 
 | |
|     return VirtualRange { base, end - base.get() };
 | |
| }
 | |
| 
 | |
| }
 |