264 lines
		
	
	
		
			6.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			264 lines
		
	
	
		
			6.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| 
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| /* This file contains the routines related to vnodes.
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|  * The entry points are:
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|  *      
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|  *  get_vnode - increase counter and get details of an inode
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|  *  get_free_vnode - get a pointer to a free vnode obj
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|  *  find_vnode - find a vnode according to the FS endpoint and the inode num.  
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|  *  dup_vnode - duplicate vnode (i.e. increase counter)
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|  *  put_vnode - drop vnode (i.e. decrease counter)  
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|  *  
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|  *  Jul 2006 (Balazs Gerofi)
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|  */
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| #include "fs.h"
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| #include "vnode.h"
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| #include "vmnt.h"
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| 
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| #include "fproc.h"
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| #include "file.h"
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| 
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| #include <minix/vfsif.h>
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| 
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| 
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| /*===========================================================================*
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|  *				get_free_vnode				     *
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|  *===========================================================================*/
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| PUBLIC struct vnode *get_free_vnode(file, line)
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| char *file;
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| int line;
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| {
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| /* Find a free vnode slot in the vnode table */    
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|   struct vnode *vp;
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| 
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|   for (vp = &vnode[0]; vp < &vnode[NR_VNODES]; ++vp)
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| 	if (vp->v_ref_count == 0)
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| 	{
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| 		vp->v_pipe= NO_PIPE;
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| 		vp->v_uid= -1;
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| 		vp->v_gid= -1;
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| 		vp->v_sdev= -1;
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| 		vp->v_file= file;
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| 		vp->v_line= line;
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| 		return vp;
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| 	}
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| 
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|   
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|   err_code = ENFILE;
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|   return NIL_VNODE;
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| }
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| 
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| /*===========================================================================*
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|  *				find_vnode				     *
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|  *===========================================================================*/
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| PUBLIC struct vnode *find_vnode(int fs_e, int numb)
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| {
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| /* Find a specified (FS endpoint and inode number) vnode in the
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|  * vnode table */
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|   struct vnode *vp;
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| 
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|   for (vp = &vnode[0]; vp < &vnode[NR_VNODES]; ++vp)
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|       if (vp->v_ref_count > 0 && vp->v_inode_nr == numb
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|               && vp->v_fs_e == fs_e) return vp;
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|   
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|   return NIL_VNODE;
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| }
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| 
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| 
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| /*===========================================================================*
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|  *				dup_vnode				     *
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|  *===========================================================================*/
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| PUBLIC void dup_vnode(struct vnode *vp)
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| {
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| /* dup_vnode() is called to increment the vnode and therefore the
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|  * referred inode's counter.
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|  */
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|   if (vp == NIL_VNODE) {
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|       printf("VFSdup_vnode NIL_VNODE\n");
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|       return;
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|   }
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| 
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|   vp->v_ref_count++;
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| }
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| 
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| 
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| /*===========================================================================*
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|  *				put_vnode				     *
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|  *===========================================================================*/
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| PUBLIC void put_vnode(struct vnode *vp)
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| {
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| /* Decrease vnode's usage counter and decrease inode's usage counter in the 
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|  * corresponding FS process.
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|  */
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|   if (vp == NIL_VNODE) {
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|         /*printf("VFSput_vnode NIL_VNODE\n");*/
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|         return;
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|   }
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| 
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|   if (vp < &vnode[0] || vp >= &vnode[NR_VNODES])
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|   {
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| 	printf("put_vnode: &vnode[0] = %p, &vnode[NR_VNODES] = %p, vp = %p\n",
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| 		&vnode[0], &vnode[NR_VNODES], vp);
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| 	panic(__FILE__, "put_vnode: bad vnode pointer", NO_NUM);
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|   }
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| 
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|   if (vp->v_ref_count > 1)
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|   {
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| 	/* Decrease counter */
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| 	vp->v_ref_count--;
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| 	if (vp->v_fs_count > 256)
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| 		vnode_clean_refs(vp);
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| 	return;
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|   }
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| 
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|   if (vp->v_ref_count <= 0)
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|   {
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| 	printf("put_vnode: bad v_ref_count %d\n", vp->v_ref_count);
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| 	panic(__FILE__, "put_vnode failed", NO_NUM);
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|   }
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|   if (vp->v_fs_count <= 0)
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|   {
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| 	printf("put_vnode: bad v_fs_count %d\n", vp->v_fs_count);
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| 	panic(__FILE__, "put_vnode failed", NO_NUM);
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|   }
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| 
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|   /* Send request */
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|   if (req_putnode(vp->v_fs_e, vp->v_inode_nr, vp->v_fs_count) != OK)
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|       printf("VFSput_vnode Warning: inode doesn't exist\n"); 
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| 
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|   vp->v_fs_count= 0;
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|   vp->v_ref_count= 0;
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|   vp->v_pipe = NO_PIPE;
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|   vp->v_sdev = NO_DEV;
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|   vp->v_index = 0;
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| }
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| 
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| 
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| /*===========================================================================*
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|  *				vnode_clean_refs			     *
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|  *===========================================================================*/
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| PUBLIC void vnode_clean_refs(struct vnode *vp)
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| {
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| /* Tell the underlying FS to drop all reference but one. */
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|   if (vp == NIL_VNODE) {
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|         return;
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|   }
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| 
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|   if (vp->v_fs_count <= 1)
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| 	return;	/* Nothing to do */
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|   if (req_putnode(vp->v_fs_e, vp->v_inode_nr, vp->v_fs_count-1) != OK)
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| 	printf("vnode_clean_refs: req_putnode failed\n"); 
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|   vp->v_fs_count= 1;
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| }
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| 
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| 
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| #if 0
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| /*===========================================================================*
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|  *				mark_vn					     *
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|  *===========================================================================*/
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| PUBLIC void mark_vn(vp, file, line)
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| struct vnode *vp;
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| char *file;
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| int line;
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| {
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| 	if (!vp)
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| 		return;
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| 	vp->v_file= file;
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| 	vp->v_line= line;
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| }
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| 
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| 
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| /*===========================================================================*
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|  *				check_vrefs				     *
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|  *===========================================================================*/
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| PUBLIC int check_vrefs()
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| {
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| 	int i, bad;
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| 	int ispipe_flag, ispipe_mode;
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| 	struct vnode *vp;
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| 	struct vmnt *vmp;
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| 	struct fproc *rfp;
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| 	struct filp *f;
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| 
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| 	/* Clear v_ref_check */
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| 	for (vp = &vnode[0]; vp < &vnode[NR_VNODES]; ++vp)
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| 		vp->v_ref_check= 0;
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| 
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| 	/* Count reference for processes */
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| 	for (rfp=&fproc[0]; rfp < &fproc[NR_PROCS]; rfp++) {
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| 		if (rfp->fp_pid == PID_FREE)
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| 			continue;
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| 		vp= rfp->fp_rd;
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| 		if (vp < &vnode[0] || vp >= &vnode[NR_VNODES])
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| 			panic(__FILE__, "check_vrefs: bad vnode", NO_NUM);
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| 		vp->v_ref_check++;
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|                 
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|                 vp= rfp->fp_wd;
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| 		if (vp < &vnode[0] || vp >= &vnode[NR_VNODES])
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| 			panic(__FILE__, "check_vrefs: bad vnode", NO_NUM);
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| 		vp->v_ref_check++;
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| 
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|   	}
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| 
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| 	/* Count references from filedescriptors */
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| 	for (f = &filp[0]; f < &filp[NR_FILPS]; f++)
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| 	{
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| 		if (f->filp_count == 0)
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| 			continue;
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| 		vp= f->filp_vno;
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| 		if (vp < &vnode[0] || vp >= &vnode[NR_VNODES])
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| 			panic(__FILE__, "check_vrefs: bad vnode", NO_NUM);
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| 		vp->v_ref_check++;
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| 	}
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| 
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| 	/* Count references to mount points */
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| 	for (vmp = &vmnt[0]; vmp < &vmnt[NR_MNTS]; ++vmp)
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| 	{
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| 		if (vmp->m_dev == NO_DEV)
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| 			continue;
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| 		vp= vmp->m_mounted_on;
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| 		if (vp < &vnode[0] || vp >= &vnode[NR_VNODES])
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| 			panic(__FILE__, "check_vrefs: bad vnode", NO_NUM);
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| 		vp->v_ref_check++;
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| 
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| 		vp= vmp->m_root_node;
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| 		if (vp < &vnode[0] || vp >= &vnode[NR_VNODES])
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| 			panic(__FILE__, "check_vrefs: bad vnode", NO_NUM);
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| 		vp->v_ref_check++;
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| 	}
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| 
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| 	/* Check references */
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| 	bad= 0;
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| 	for (vp = &vnode[0]; vp < &vnode[NR_VNODES]; ++vp)
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| 	{
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| 		if (vp->v_ref_count != vp->v_ref_check)
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| 		{
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| 			printf(
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| "Bad reference count for inode %d on device 0x%x: found %d, listed %d\n",
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| 				vp->v_inode_nr, vp->v_dev, vp->v_ref_check,
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| 				vp->v_ref_count);
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| 			printf("last marked at %s, %d\n",
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| 				vp->v_file, vp->v_line);
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| 			bad= 1;
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| 		}
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| 
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| 		/* Also check v_pipe */
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| 		if (vp->v_ref_count != 0)
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| 		{
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| 			ispipe_flag= (vp->v_pipe == I_PIPE);
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| 			ispipe_mode= ((vp->v_mode & I_TYPE) == I_NAMED_PIPE);
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| 			if (ispipe_flag != ispipe_mode)
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| 			{
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| 				printf(
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| "Bad v_pipe for inode %d on device 0x%x: found %d, mode 0%o\n",
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| 				vp->v_inode_nr, vp->v_dev, vp->v_pipe,
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| 				vp->v_mode);
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| 				printf("last marked at %s, %d\n",
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| 					vp->v_file, vp->v_line);
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| 				bad= 1;
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| 			}
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| 		}
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| 	}
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| 	return !bad;
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| }
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| #endif
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