only delete space used by inode, on inode deletion; required

[unix-history] / usr / src / sys / vm / device_pager.h

/*
* Copyright (c) 1990 University of Utah.
* Copyright (c) 1991 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* %sccs.include.redist.c%
*
*      @(#)device_pager.h      7.1 (Berkeley) %G%
*/

#ifndef _DEVICE_PAGER_
#define _DEVICE_PAGER_  1

/*
* Device pager private data.
*/
struct devpager {
       queue_head_t    devp_list;      /* list of managed devices */
       dev_t           devp_dev;       /* devno of device */
       vm_page_t       devp_pages;     /* page structs for device */
       int             devp_npages;    /* size of device in pages */
       int             devp_count;     /* reference count */
       vm_object_t     devp_object;    /* object representing this device */
};
typedef struct devpager *dev_pager_t;

#define DEV_PAGER_NULL  ((dev_pager_t)0)

#ifdef KERNEL

void            dev_pager_init();
vm_pager_t      dev_pager_alloc();
void            dev_pager_dealloc();
boolean_t       dev_pager_getpage(), dev_pager_putpage();
boolean_t       dev_pager_haspage();

struct pagerops devicepagerops = {
       dev_pager_init,
       dev_pager_alloc,
       dev_pager_dealloc,
       dev_pager_getpage,
       dev_pager_putpage,
       dev_pager_haspage
};

#endif

#endif  /* _DEVICE_PAGER_ */