[apple/xnu.git] / bsd / vm / dp_backing_file.c

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */

#include <mach/boolean.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/lock.h>
#include <sys/proc.h>
#include <sys/buf.h>
#include <sys/uio.h>
#include <sys/vnode.h>
#include <sys/namei.h>
#include <sys/ubc.h>

#include <mach/mach_types.h>
#include <vm/vm_map.h>
#include <vm/vm_kern.h>
#include <kern/host.h>
#include <kern/zalloc.h>
#include <kern/kalloc.h>
#include <libkern/libkern.h>
#include <sys/malloc.h>

#include <vm/vnode_pager.h>

/*
 * temporary support for delayed instantiation
 * of default_pager
 */
int default_pager_init_flag = 0;

struct bs_map		bs_port_table[MAX_BACKING_STORE] = { 
	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}};

/* ###################################################### */


#include <kern/assert.h>

/*
 *	Routine:	macx_backing_store_recovery
 *	Function:
 *		Syscall interface to set a tasks privilege
 *		level so that it is not subject to 
 *		macx_backing_store_suspend
 */
int
macx_backing_store_recovery(
	int		pid)
{
	int		error;
	struct proc	*p =  current_proc();
	boolean_t	funnel_state;

	funnel_state = thread_funnel_set(kernel_flock, TRUE);
	if ((error = suser(p->p_ucred, &p->p_acflag)))
		goto backing_store_recovery_return;

	/* for now restrict backing_store_recovery */
	/* usage to only present task */
	if(pid != p->p_pid) {
		error = EINVAL;
		goto backing_store_recovery_return;
	}

	task_backing_store_privileged(p->task);

backing_store_recovery_return:
	(void) thread_funnel_set(kernel_flock, FALSE);
	return(error);
}

/*
 *	Routine:	macx_backing_store_suspend
 *	Function:
 *		Syscall interface to stop new demand for 
 *		backing store when backing store is low
 */

int
macx_backing_store_suspend(
	boolean_t	suspend)
{
	int		error;
	struct proc	*p =  current_proc();
	boolean_t	funnel_state;

	funnel_state = thread_funnel_set(kernel_flock, TRUE);
	if ((error = suser(p->p_ucred, &p->p_acflag)))
		goto backing_store_suspend_return;

	vm_backing_store_disable(suspend);

backing_store_suspend_return:
	(void) thread_funnel_set(kernel_flock, FALSE);
	return(error);
}

/*
 *	Routine:	macx_swapon
 *	Function:
 *		Syscall interface to add a file to backing store
 */
int
macx_swapon(
	char 	*filename,
	int	flags,
	long	size,
	long	priority)
{
	struct vnode		*vp = 0; 
	struct nameidata 	nd, *ndp;
	struct proc		*p =  current_proc();
	pager_file_t		pf;
	register int		error;
	kern_return_t		kr;
	mach_port_t		backing_store;
	memory_object_default_t	default_pager;
	int			i;
	boolean_t		funnel_state;

	struct vattr	vattr;

	funnel_state = thread_funnel_set(kernel_flock, TRUE);
	ndp = &nd;

	if ((error = suser(p->p_ucred, &p->p_acflag)))
		goto swapon_bailout;

	if(default_pager_init_flag == 0) {
		start_def_pager(NULL);
		default_pager_init_flag = 1;
	}

	/*
	 * Get a vnode for the paging area.
	 */
	NDINIT(ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_USERSPACE,
	    filename, p);

	if ((error = namei(ndp)))
		goto swapon_bailout;
	vp = ndp->ni_vp;

	if (vp->v_type != VREG) {
		error = EINVAL;
	        VOP_UNLOCK(vp, 0, p);
		goto swapon_bailout;
	}
	UBCINFOCHECK("macx_swapon", vp);

	if (error = VOP_GETATTR(vp, &vattr, p->p_ucred, p)) {
	        VOP_UNLOCK(vp, 0, p);
		goto swapon_bailout;
	}

	if (vattr.va_size < (u_quad_t)size) {
		vattr_null(&vattr);
		vattr.va_size = (u_quad_t)size;
		error = VOP_SETATTR(vp, &vattr, p->p_ucred, p);
		if (error) {
			VOP_UNLOCK(vp, 0, p);
			goto swapon_bailout;
		}
	}

	/* add new backing store to list */
	i = 0;
	while(bs_port_table[i].vp != 0) {
		if(i == MAX_BACKING_STORE)
			break;
		i++;
	}
	if(i == MAX_BACKING_STORE) {
	   	error = ENOMEM;
	        VOP_UNLOCK(vp, 0, p);
		goto swapon_bailout;
	}

	/* remember the vnode. This vnode has namei() reference */
	bs_port_table[i].vp = vp;
	
	/*
	 * Look to see if we are already paging to this file.
	 */
	/* make certain the copy send of kernel call will work */
	default_pager = MEMORY_OBJECT_DEFAULT_NULL;
	kr = host_default_memory_manager(host_priv_self(), &default_pager, 0);
	if(kr != KERN_SUCCESS) {
	   error = EAGAIN;
	   VOP_UNLOCK(vp, 0, p);
	   bs_port_table[i].vp = 0;
	   goto swapon_bailout;
	}

	kr = default_pager_backing_store_create(default_pager, 
					-1, /* default priority */
					0, /* default cluster size */
					&backing_store);
	memory_object_default_deallocate(default_pager);

	if(kr != KERN_SUCCESS) {
	   error = ENOMEM;
	   VOP_UNLOCK(vp, 0, p);
	   bs_port_table[i].vp = 0;
	   goto swapon_bailout;
	}

	/*
	 * NOTE: we are able to supply PAGE_SIZE here instead of
	 *	an actual record size or block number because:
	 *	a: we do not support offsets from the beginning of the
	 *		file (allowing for non page size/record modulo offsets.
	 *	b: because allow paging will be done modulo page size
	 */

	VOP_UNLOCK(vp, 0, p);
	kr = default_pager_add_file(backing_store, vp, PAGE_SIZE, 
			((int)vattr.va_size)/PAGE_SIZE);
	if(kr != KERN_SUCCESS) {
	   bs_port_table[i].vp = 0;
	   if(kr == KERN_INVALID_ARGUMENT)
		error = EINVAL;
	   else 
		error = ENOMEM;
	   goto swapon_bailout;
	}
	bs_port_table[i].bs = (void *)backing_store;
	error = 0;
	if (!ubc_hold(vp))
		panic("macx_swapon: hold");

	/* Mark this vnode as being used for swapfile */
	SET(vp->v_flag, VSWAP);

	ubc_setcred(vp, p);

	/*
	 * take an extra reference on the vnode to keep
	 * vnreclaim() away from this vnode.
	 */
	VREF(vp);

	/* Hold on to the namei  reference to the paging file vnode */
	vp = 0;

swapon_bailout:
	if (vp) {
		vrele(vp);
	}
	(void) thread_funnel_set(kernel_flock, FALSE);
	return(error);
}

/*
 *	Routine:	macx_swapoff
 *	Function:
 *		Syscall interface to remove a file from backing store
 */
int
macx_swapoff(
	char 	*filename,
	int	flags)
{
	kern_return_t	kr;
	mach_port_t	backing_store;

	struct vnode		*vp = 0; 
	struct nameidata 	nd, *ndp;
	struct proc		*p =  current_proc();
	int			i;
	int			error;
	boolean_t		funnel_state;

	funnel_state = thread_funnel_set(kernel_flock, TRUE);
	backing_store = NULL;
	ndp = &nd;

	if ((error = suser(p->p_ucred, &p->p_acflag)))
		goto swapoff_bailout;

	/*
	 * Get the vnode for the paging area.
	 */
	NDINIT(ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_USERSPACE,
	    filename, p);

	if ((error = namei(ndp)))
		goto swapoff_bailout;
	vp = ndp->ni_vp;

	if (vp->v_type != VREG) {
		error = EINVAL;
		VOP_UNLOCK(vp, 0, p);
		goto swapoff_bailout;
	}

	for(i = 0; i < MAX_BACKING_STORE; i++) {
		if(bs_port_table[i].vp == vp) {
			backing_store; 
			break;
		}
	}
	if (i == MAX_BACKING_STORE) {
		error = EINVAL;
		VOP_UNLOCK(vp, 0, p);
		goto swapoff_bailout;
	}
	backing_store = (mach_port_t)bs_port_table[i].bs;

	VOP_UNLOCK(vp, 0, p);
	kr = default_pager_backing_store_delete(backing_store);
	switch (kr) {
		case KERN_SUCCESS:
			error = 0;
			bs_port_table[i].vp = 0;
			ubc_rele(vp);
			/* This vnode is no longer used for swapfile */
			CLR(vp->v_flag, VSWAP);

			/* get rid of macx_swapon() namei() reference */
			vrele(vp);

			/* get rid of macx_swapon() "extra" reference */
			vrele(vp);
			break;
		case KERN_FAILURE:
			error = EAGAIN;
			break;
		default:
			error = EAGAIN;
			break;
	}

swapoff_bailout:
	/* get rid of macx_swapoff() namei() reference */
	if (vp)
		vrele(vp);

	(void) thread_funnel_set(kernel_flock, FALSE);
	return(error);
}
Commit	Line	Data
1c79356b A	1	/*
	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
43866e37	6	* Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
1c79356b	7	*
43866e37 A	8	* This file contains Original Code and/or Modifications of Original Code
	9	* as defined in and that are subject to the Apple Public Source License
	10	* Version 2.0 (the 'License'). You may not use this file except in
	11	* compliance with the License. Please obtain a copy of the License at
	12	* http://www.opensource.apple.com/apsl/ and read it before using this
	13	* file.
	14	*
	15	* The Original Code and all software distributed under the License are
	16	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
1c79356b A	17	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
1c79356b A	18	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
43866e37 A	19	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	20	* Please see the License for the specific language governing rights and
	21	* limitations under the License.
1c79356b A	22	*
	23	* @APPLE_LICENSE_HEADER_END@
	24	*/
	25
	26	#include <mach/boolean.h>
	27	#include <sys/param.h>
	28	#include <sys/systm.h>
	29	#include <sys/lock.h>
	30	#include <sys/proc.h>
	31	#include <sys/buf.h>
	32	#include <sys/uio.h>
	33	#include <sys/vnode.h>
	34	#include <sys/namei.h>
	35	#include <sys/ubc.h>
	36
	37	#include <mach/mach_types.h>
	38	#include <vm/vm_map.h>
	39	#include <vm/vm_kern.h>
	40	#include <kern/host.h>
1c79356b A	41	#include <kern/zalloc.h>
	42	#include <kern/kalloc.h>
	43	#include <libkern/libkern.h>
	44	#include <sys/malloc.h>
	45
	46	#include <vm/vnode_pager.h>
	47
	48	/*
	49	* temporary support for delayed instantiation
	50	* of default_pager
	51	*/
	52	int default_pager_init_flag = 0;
	53
	54	struct bs_map bs_port_table[MAX_BACKING_STORE] = {
	55	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	56	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	57	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	58	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	59	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	60	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	61	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	62	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	63	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},
	64	{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0},{0,0}};
	65
	66	/* ###################################################### */
	67
	68
	69	#include <kern/assert.h>
	70
55e303ae A	71	/*
	72	* Routine: macx_backing_store_recovery
	73	* Function:
	74	* Syscall interface to set a tasks privilege
	75	* level so that it is not subject to
	76	* macx_backing_store_suspend
	77	*/
	78	int
	79	macx_backing_store_recovery(
	80	int pid)
	81	{
	82	int error;
	83	struct proc *p = current_proc();
	84	boolean_t funnel_state;
	85
	86	funnel_state = thread_funnel_set(kernel_flock, TRUE);
	87	if ((error = suser(p->p_ucred, &p->p_acflag)))
	88	goto backing_store_recovery_return;
	89
	90	/* for now restrict backing_store_recovery */
	91	/* usage to only present task */
	92	if(pid != p->p_pid) {
	93	error = EINVAL;
	94	goto backing_store_recovery_return;
	95	}
	96
	97	task_backing_store_privileged(p->task);
	98
	99	backing_store_recovery_return:
	100	(void) thread_funnel_set(kernel_flock, FALSE);
	101	return(error);
	102	}
	103
	104	/*
	105	* Routine: macx_backing_store_suspend
	106	* Function:
	107	* Syscall interface to stop new demand for
	108	* backing store when backing store is low
	109	*/
	110
	111	int
	112	macx_backing_store_suspend(
	113	boolean_t suspend)
	114	{
	115	int error;
	116	struct proc *p = current_proc();
	117	boolean_t funnel_state;
	118
	119	funnel_state = thread_funnel_set(kernel_flock, TRUE);
	120	if ((error = suser(p->p_ucred, &p->p_acflag)))
	121	goto backing_store_suspend_return;
	122
	123	vm_backing_store_disable(suspend);
	124
	125	backing_store_suspend_return:
	126	(void) thread_funnel_set(kernel_flock, FALSE);
	127	return(error);
	128	}
	129
1c79356b A	130	/*
	131	* Routine: macx_swapon
	132	* Function:
	133	* Syscall interface to add a file to backing store
	134	*/
	135	int
	136	macx_swapon(
	137	char *filename,
	138	int flags,
	139	long size,
	140	long priority)
	141	{
	142	struct vnode *vp = 0;
	143	struct nameidata nd, *ndp;
	144	struct proc *p = current_proc();
	145	pager_file_t pf;
	146	register int error;
	147	kern_return_t kr;
	148	mach_port_t backing_store;
0b4e3aa0	149	memory_object_default_t default_pager;
1c79356b A	150	int i;
	151	boolean_t funnel_state;
	152
	153	struct vattr vattr;
	154
	155	funnel_state = thread_funnel_set(kernel_flock, TRUE);
	156	ndp = &nd;
	157
	158	if ((error = suser(p->p_ucred, &p->p_acflag)))
	159	goto swapon_bailout;
	160
1c79356b A	161	if(default_pager_init_flag == 0) {
	162	start_def_pager(NULL);
	163	default_pager_init_flag = 1;
	164	}
	165
	166	/*
	167	* Get a vnode for the paging area.
	168	*/
	169	NDINIT(ndp, LOOKUP, FOLLOW \| LOCKLEAF, UIO_USERSPACE,
	170	filename, p);
	171
	172	if ((error = namei(ndp)))
	173	goto swapon_bailout;
	174	vp = ndp->ni_vp;
	175
	176	if (vp->v_type != VREG) {
	177	error = EINVAL;
	178	VOP_UNLOCK(vp, 0, p);
	179	goto swapon_bailout;
	180	}
	181	UBCINFOCHECK("macx_swapon", vp);
	182
	183	if (error = VOP_GETATTR(vp, &vattr, p->p_ucred, p)) {
	184	VOP_UNLOCK(vp, 0, p);
	185	goto swapon_bailout;
	186	}
	187
	188	if (vattr.va_size < (u_quad_t)size) {
	189	vattr_null(&vattr);
	190	vattr.va_size = (u_quad_t)size;
	191	error = VOP_SETATTR(vp, &vattr, p->p_ucred, p);
	192	if (error) {
	193	VOP_UNLOCK(vp, 0, p);
	194	goto swapon_bailout;
	195	}
	196	}
	197
	198	/* add new backing store to list */
	199	i = 0;
	200	while(bs_port_table[i].vp != 0) {
	201	if(i == MAX_BACKING_STORE)
	202	break;
	203	i++;
	204	}
	205	if(i == MAX_BACKING_STORE) {
	206	error = ENOMEM;
	207	VOP_UNLOCK(vp, 0, p);
	208	goto swapon_bailout;
	209	}
	210
	211	/* remember the vnode. This vnode has namei() reference */
	212	bs_port_table[i].vp = vp;
	213
	214	/*
	215	* Look to see if we are already paging to this file.
	216	*/
	217	/* make certain the copy send of kernel call will work */
0b4e3aa0 A	218	default_pager = MEMORY_OBJECT_DEFAULT_NULL;
0b4e3aa0 A	219	kr = host_default_memory_manager(host_priv_self(), &default_pager, 0);
1c79356b A	220	if(kr != KERN_SUCCESS) {
	221	error = EAGAIN;
	222	VOP_UNLOCK(vp, 0, p);
	223	bs_port_table[i].vp = 0;
	224	goto swapon_bailout;
	225	}
	226
0b4e3aa0	227	kr = default_pager_backing_store_create(default_pager,
1c79356b A	228	-1, /* default priority */
	229	0, /* default cluster size */
	230	&backing_store);
0b4e3aa0 A	231	memory_object_default_deallocate(default_pager);
0b4e3aa0 A	232
1c79356b A	233	if(kr != KERN_SUCCESS) {
	234	error = ENOMEM;
	235	VOP_UNLOCK(vp, 0, p);
	236	bs_port_table[i].vp = 0;
	237	goto swapon_bailout;
	238	}
	239
	240	/*
	241	* NOTE: we are able to supply PAGE_SIZE here instead of
	242	* an actual record size or block number because:
	243	* a: we do not support offsets from the beginning of the
	244	* file (allowing for non page size/record modulo offsets.
	245	* b: because allow paging will be done modulo page size
	246	*/
	247
	248	VOP_UNLOCK(vp, 0, p);
	249	kr = default_pager_add_file(backing_store, vp, PAGE_SIZE,
	250	((int)vattr.va_size)/PAGE_SIZE);
	251	if(kr != KERN_SUCCESS) {
	252	bs_port_table[i].vp = 0;
	253	if(kr == KERN_INVALID_ARGUMENT)
	254	error = EINVAL;
	255	else
	256	error = ENOMEM;
	257	goto swapon_bailout;
	258	}
	259	bs_port_table[i].bs = (void *)backing_store;
	260	error = 0;
	261	if (!ubc_hold(vp))
	262	panic("macx_swapon: hold");
	263
	264	/* Mark this vnode as being used for swapfile */
	265	SET(vp->v_flag, VSWAP);
	266
55e303ae A	267	ubc_setcred(vp, p);
55e303ae A	268
1c79356b A	269	/*
	270	* take an extra reference on the vnode to keep
	271	* vnreclaim() away from this vnode.
	272	*/
	273	VREF(vp);
	274
	275	/* Hold on to the namei reference to the paging file vnode */
	276	vp = 0;
	277
	278	swapon_bailout:
	279	if (vp) {
	280	vrele(vp);
	281	}
1c79356b A	282	(void) thread_funnel_set(kernel_flock, FALSE);
	283	return(error);
	284	}
	285
	286	/*
	287	* Routine: macx_swapoff
	288	* Function:
	289	* Syscall interface to remove a file from backing store
	290	*/
	291	int
	292	macx_swapoff(
	293	char *filename,
	294	int flags)
	295	{
	296	kern_return_t kr;
	297	mach_port_t backing_store;
	298
	299	struct vnode *vp = 0;
	300	struct nameidata nd, *ndp;
	301	struct proc *p = current_proc();
	302	int i;
	303	int error;
	304	boolean_t funnel_state;
	305
	306	funnel_state = thread_funnel_set(kernel_flock, TRUE);
	307	backing_store = NULL;
	308	ndp = &nd;
	309
	310	if ((error = suser(p->p_ucred, &p->p_acflag)))
	311	goto swapoff_bailout;
	312
1c79356b A	313	/*
	314	* Get the vnode for the paging area.
	315	*/
	316	NDINIT(ndp, LOOKUP, FOLLOW \| LOCKLEAF, UIO_USERSPACE,
	317	filename, p);
	318
	319	if ((error = namei(ndp)))
	320	goto swapoff_bailout;
	321	vp = ndp->ni_vp;
	322
	323	if (vp->v_type != VREG) {
	324	error = EINVAL;
	325	VOP_UNLOCK(vp, 0, p);
	326	goto swapoff_bailout;
	327	}
	328
	329	for(i = 0; i < MAX_BACKING_STORE; i++) {
	330	if(bs_port_table[i].vp == vp) {
	331	backing_store;
	332	break;
	333	}
	334	}
	335	if (i == MAX_BACKING_STORE) {
	336	error = EINVAL;
	337	VOP_UNLOCK(vp, 0, p);
	338	goto swapoff_bailout;
	339	}
	340	backing_store = (mach_port_t)bs_port_table[i].bs;
	341
	342	VOP_UNLOCK(vp, 0, p);
	343	kr = default_pager_backing_store_delete(backing_store);
	344	switch (kr) {
	345	case KERN_SUCCESS:
	346	error = 0;
	347	bs_port_table[i].vp = 0;
	348	ubc_rele(vp);
	349	/* This vnode is no longer used for swapfile */
	350	CLR(vp->v_flag, VSWAP);
	351
	352	/* get rid of macx_swapon() namei() reference */
	353	vrele(vp);
	354
	355	/* get rid of macx_swapon() "extra" reference */
	356	vrele(vp);
	357	break;
	358	case KERN_FAILURE:
	359	error = EAGAIN;
	360	break;
	361	default:
	362	error = EAGAIN;
	363	break;
	364	}
	365
	366	swapoff_bailout:
	367	/* get rid of macx_swapoff() namei() reference */
	368	if (vp)
	369	vrele(vp);
	370
1c79356b A	371	(void) thread_funnel_set(kernel_flock, FALSE);
	372	return(error);
	373	}