121 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			121 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| 
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| #define _SYSTEM 1
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| 
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| #include <minix/callnr.h>
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| #include <minix/com.h>
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| #include <minix/config.h>
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| #include <minix/const.h>
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| #include <minix/ds.h>
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| #include <minix/endpoint.h>
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| #include <minix/keymap.h>
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| #include <minix/minlib.h>
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| #include <minix/type.h>
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| #include <minix/ipc.h>
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| #include <minix/sysutil.h>
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| #include <minix/syslib.h>
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| #include <minix/debug.h>
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| #include <minix/bitmap.h>
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| 
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| #include <string.h>
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| #include <errno.h>
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| #include <env.h>
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| #include <assert.h>
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| 
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| #include "glo.h"
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| #include "vm.h"
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| #include "proto.h"
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| #include "util.h"
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| #include "sanitycheck.h"
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| #include "region.h"
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| #include "memory.h"
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| 
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| /*===========================================================================*
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|  *				do_fork					     *
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|  *===========================================================================*/
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| int do_fork(message *msg)
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| {
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|   int r, proc, childproc;
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|   struct vmproc *vmp, *vmc;
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|   pt_t origpt;
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|   vir_bytes msgaddr;
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| 
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|   SANITYCHECK(SCL_FUNCTIONS);
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| 
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|   if(vm_isokendpt(msg->VMF_ENDPOINT, &proc) != OK) {
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| 	printf("VM: bogus endpoint VM_FORK %d\n", msg->VMF_ENDPOINT);
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|   SANITYCHECK(SCL_FUNCTIONS);
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| 	return EINVAL;
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|   }
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| 
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|   childproc = msg->VMF_SLOTNO;
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|   if(childproc < 0 || childproc >= NR_PROCS) {
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| 	printf("VM: bogus slotno VM_FORK %d\n", msg->VMF_SLOTNO);
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|   SANITYCHECK(SCL_FUNCTIONS);
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| 	return EINVAL;
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|   }
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| 
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|   vmp = &vmproc[proc];		/* parent */
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|   vmc = &vmproc[childproc];	/* child */
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|   assert(vmc->vm_slot == childproc);
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| 
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|   /* The child is basically a copy of the parent. */
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|   origpt = vmc->vm_pt;
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|   *vmc = *vmp;
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|   vmc->vm_slot = childproc;
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|   region_init(&vmc->vm_regions_avl);
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|   vmc->vm_endpoint = NONE;	/* In case someone tries to use it. */
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|   vmc->vm_pt = origpt;
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| 
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| #if VMSTATS
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|   vmc->vm_bytecopies = 0;
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| #endif
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| 
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|   if(pt_new(&vmc->vm_pt) != OK) {
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| 	printf("VM: fork: pt_new failed\n");
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| 	return ENOMEM;
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|   }
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| 
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|   SANITYCHECK(SCL_DETAIL);
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| 
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|   if(map_proc_copy(vmc, vmp) != OK) {
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| 	printf("VM: fork: map_proc_copy failed\n");
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| 	pt_free(&vmc->vm_pt);
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| 	return(ENOMEM);
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|   }
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| 
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|   /* Only inherit these flags. */
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|   vmc->vm_flags &= VMF_INUSE;
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| 
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|   /* inherit the priv call bitmaps */
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|   memcpy(&vmc->vm_call_mask, &vmp->vm_call_mask, sizeof(vmc->vm_call_mask));
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| 
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|   /* Tell kernel about the (now successful) FORK. */
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|   if((r=sys_fork(vmp->vm_endpoint, childproc,
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| 	&vmc->vm_endpoint, PFF_VMINHIBIT, &msgaddr)) != OK) {
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|         panic("do_fork can't sys_fork: %d", r);
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|   }
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| 
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|   if((r=pt_bind(&vmc->vm_pt, vmc)) != OK)
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| 	panic("fork can't pt_bind: %d", r);
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| 
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|   {
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| 	vir_bytes vir;
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| 	/* making these messages writable is an optimisation
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| 	 * and its return value needn't be checked.
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| 	 */
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| 	vir = msgaddr;
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| 	if (handle_memory(vmc, vir, sizeof(message), 1) != OK)
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| 	    panic("do_fork: handle_memory for child failed\n");
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| 	vir = msgaddr;
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| 	if (handle_memory(vmp, vir, sizeof(message), 1) != OK)
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| 	    panic("do_fork: handle_memory for parent failed\n");
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|   }
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| 
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|   /* Inform caller of new child endpoint. */
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|   msg->VMF_CHILD_ENDPOINT = vmc->vm_endpoint;
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| 
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|   SANITYCHECK(SCL_FUNCTIONS);
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|   return OK;
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| }
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| 
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