forked from xt-sys/exectos
		
	
		
			
				
	
	
		
			59 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			59 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| /**
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|  * PROJECT:         ExectOS
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|  * COPYRIGHT:       See COPYING.md in the top level directory
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|  * FILE:            xtoskrnl/mm/amd64/paging.cc
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|  * DESCRIPTION:     Architecture dependent paging support
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|  * DEVELOPERS:      Rafal Kupiec <belliash@codingworkshop.eu.org>
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|  *                  Aiken Harris <harraiken91@gmail.com>
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|  */
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| 
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| #include <xtos.hh>
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| 
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| 
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| /**
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|  * Checks if eXtended Physical Addressing (XPA) is enabled.
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|  *
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|  * @return This routine returns TRUE if LA57 is enabled, or FALSE otherwise.
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|  *
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|  * @since XT 1.0
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|  */
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| XTAPI
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| BOOLEAN
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| MM::Paging::GetExtendedPhysicalAddressingStatus(VOID)
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| {
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|     /* Check if LA57 is enabled */
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|     return ((AR::CpuFunc::ReadControlRegister(4) & CR4_LA57) != 0) ? TRUE : FALSE;
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| }
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| 
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| /**
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|  * Fills a section of memory with zeroes like RtlZeroMemory(), but in more efficient way.
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|  *
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|  * @param Address
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|  *        Supplies an address of the page to be filled with zeroes.
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|  *
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|  * @param Size
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|  *        Number of bytes to be filled with zeros. This always should be a multiply of page size.
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|  *
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|  * @return This routine does not return any value.
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|  *
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|  * @since XT 1.0
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|  */
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| XTFASTCALL
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| VOID
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| MM::Paging::ZeroPages(IN PVOID Address,
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|                       IN ULONG Size)
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| {
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|     __asm__ volatile("xor %%rax, %%rax\n"
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|                      "mov %0, %%rdi\n"
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|                      "mov %1, %%ecx\n"
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|                      "shr $3, %%ecx\n"
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|                      "rep stosq\n"
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|                      :
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|                      : "m" (Address),
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|                        "m" (Size)
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|                      : "rax",
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|                        "rdi",
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|                        "ecx",
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|                        "memory");
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| }
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