47 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			47 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* The system call implemented in this file:
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|  *   m_type:	SYS_INT86
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|  *
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|  * The parameters for this system call are:
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|  *    m1_p1:	INT86_REG86     
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|  */
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| 
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| #include "../system.h"
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| #include <minix/type.h>
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| #include <ibm/int86.h>
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| 
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| struct reg86u reg86;
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| 
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| /*===========================================================================*
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|  *				do_int86					     *
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|  *===========================================================================*/
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| PUBLIC int do_int86(m_ptr)
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| register message *m_ptr;	/* pointer to request message */
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| {
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|   int caller;
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|   vir_bytes caller_vir;
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|   phys_bytes caller_phys, kernel_phys;
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| 
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|   caller = (int) m_ptr->m_source; 
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|   caller_vir = (vir_bytes) m_ptr->INT86_REG86;
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|   caller_phys = umap_local(proc_addr(caller), D, caller_vir, sizeof(reg86));
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|   if (0 == caller_phys) return(EFAULT);
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|   kernel_phys = vir2phys(®86);
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|   phys_copy(caller_phys, kernel_phys, (phys_bytes) sizeof(reg86));
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| 
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|   level0(int86);
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| 
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|   /* Copy results back to the caller */
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|   phys_copy(kernel_phys, caller_phys, (phys_bytes) sizeof(reg86));
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| 
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|   /* The BIOS call eats interrupts. Call get_randomness to generate some
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|    * entropy. Normally, get_randomness is called from an interrupt handler.
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|    * Figuring out the exact source is too complicated. CLOCK_IRQ is normally
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|    * not very random.
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|    */
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|   lock(0, "do_int86");
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|   get_randomness(CLOCK_IRQ);
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|   unlock(0);
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| 
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|   return(OK);
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| }
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