. new mode for sys_memset: include process so memset can be done in physical or virtual address space. . add a mode to mmap() that lets a process allocate uninitialized memory. . this allows an exec()er (RS, VFS, etc.) to request uninitialized memory from VM and selectively clear the ranges that don't come from a file, leaving no uninitialized memory left for the process to see. . use callbacks for clearing the process, clearing memory in the process, and copying into the process; so that the libexec code can be used from rs, vfs, and in the future, kernel (to load vm) and vm (to load boot-time processes)
		
			
				
	
	
		
			28 lines
		
	
	
		
			810 B
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			28 lines
		
	
	
		
			810 B
		
	
	
	
		
			C
		
	
	
	
	
	
/* The kernel call implemented in this file:
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 *   m_type:	SYS_MEMSET
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 *
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 * The parameters for this kernel call are:
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 *    m2_p1:	MEM_PTR		(virtual address)	
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 *    m2_l1:	MEM_COUNT	(returns physical address)	
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 *    m2_l2:	MEM_PATTERN	(pattern byte to be written) 	
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 */
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#include "kernel/system.h"
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#if USE_MEMSET
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/*===========================================================================*
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 *				do_memset				     *
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 *===========================================================================*/
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int do_memset(struct proc * caller, message * m_ptr)
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{
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/* Handle sys_memset(). This writes a pattern into the specified memory. */
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  unsigned char c = m_ptr->MEM_PATTERN;
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  vm_memset(m_ptr->MEM_PROCESS, (phys_bytes) m_ptr->MEM_PTR,
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  	c, (phys_bytes) m_ptr->MEM_COUNT);
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  return(OK);
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}
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#endif /* USE_MEMSET */
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