[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_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);

	/*
	 * 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
	71	/*
	72	* Routine: macx_swapon
	73	* Function:
	74	* Syscall interface to add a file to backing store
	75	*/
	76	int
	77	macx_swapon(
	78	char *filename,
	79	int flags,
	80	long size,
	81	long priority)
	82	{
	83	struct vnode *vp = 0;
	84	struct nameidata nd, *ndp;
	85	struct proc *p = current_proc();
	86	pager_file_t pf;
	87	register int error;
	88	kern_return_t kr;
	89	mach_port_t backing_store;
0b4e3aa0	90	memory_object_default_t default_pager;
1c79356b A	91	int i;
	92	boolean_t funnel_state;
	93
	94	struct vattr vattr;
	95
	96	funnel_state = thread_funnel_set(kernel_flock, TRUE);
	97	ndp = &nd;
	98
	99	if ((error = suser(p->p_ucred, &p->p_acflag)))
	100	goto swapon_bailout;
	101
1c79356b A	102	if(default_pager_init_flag == 0) {
	103	start_def_pager(NULL);
	104	default_pager_init_flag = 1;
	105	}
	106
	107	/*
	108	* Get a vnode for the paging area.
	109	*/
	110	NDINIT(ndp, LOOKUP, FOLLOW \| LOCKLEAF, UIO_USERSPACE,
	111	filename, p);
	112
	113	if ((error = namei(ndp)))
	114	goto swapon_bailout;
	115	vp = ndp->ni_vp;
	116
	117	if (vp->v_type != VREG) {
	118	error = EINVAL;
	119	VOP_UNLOCK(vp, 0, p);
	120	goto swapon_bailout;
	121	}
	122	UBCINFOCHECK("macx_swapon", vp);
	123
	124	if (error = VOP_GETATTR(vp, &vattr, p->p_ucred, p)) {
	125	VOP_UNLOCK(vp, 0, p);
	126	goto swapon_bailout;
	127	}
	128
	129	if (vattr.va_size < (u_quad_t)size) {
	130	vattr_null(&vattr);
	131	vattr.va_size = (u_quad_t)size;
	132	error = VOP_SETATTR(vp, &vattr, p->p_ucred, p);
	133	if (error) {
	134	VOP_UNLOCK(vp, 0, p);
	135	goto swapon_bailout;
	136	}
	137	}
	138
	139	/* add new backing store to list */
	140	i = 0;
	141	while(bs_port_table[i].vp != 0) {
	142	if(i == MAX_BACKING_STORE)
	143	break;
	144	i++;
	145	}
	146	if(i == MAX_BACKING_STORE) {
	147	error = ENOMEM;
	148	VOP_UNLOCK(vp, 0, p);
	149	goto swapon_bailout;
	150	}
	151
	152	/* remember the vnode. This vnode has namei() reference */
	153	bs_port_table[i].vp = vp;
	154
	155	/*
	156	* Look to see if we are already paging to this file.
	157	*/
	158	/* make certain the copy send of kernel call will work */
0b4e3aa0 A	159	default_pager = MEMORY_OBJECT_DEFAULT_NULL;
0b4e3aa0 A	160	kr = host_default_memory_manager(host_priv_self(), &default_pager, 0);
1c79356b A	161	if(kr != KERN_SUCCESS) {
	162	error = EAGAIN;
	163	VOP_UNLOCK(vp, 0, p);
	164	bs_port_table[i].vp = 0;
	165	goto swapon_bailout;
	166	}
	167
0b4e3aa0	168	kr = default_pager_backing_store_create(default_pager,
1c79356b A	169	-1, /* default priority */
	170	0, /* default cluster size */
	171	&backing_store);
0b4e3aa0 A	172	memory_object_default_deallocate(default_pager);
0b4e3aa0 A	173
1c79356b A	174	if(kr != KERN_SUCCESS) {
	175	error = ENOMEM;
	176	VOP_UNLOCK(vp, 0, p);
	177	bs_port_table[i].vp = 0;
	178	goto swapon_bailout;
	179	}
	180
	181	/*
	182	* NOTE: we are able to supply PAGE_SIZE here instead of
	183	* an actual record size or block number because:
	184	* a: we do not support offsets from the beginning of the
	185	* file (allowing for non page size/record modulo offsets.
	186	* b: because allow paging will be done modulo page size
	187	*/
	188
	189	VOP_UNLOCK(vp, 0, p);
	190	kr = default_pager_add_file(backing_store, vp, PAGE_SIZE,
	191	((int)vattr.va_size)/PAGE_SIZE);
	192	if(kr != KERN_SUCCESS) {
	193	bs_port_table[i].vp = 0;
	194	if(kr == KERN_INVALID_ARGUMENT)
	195	error = EINVAL;
	196	else
	197	error = ENOMEM;
	198	goto swapon_bailout;
	199	}
	200	bs_port_table[i].bs = (void *)backing_store;
	201	error = 0;
	202	if (!ubc_hold(vp))
	203	panic("macx_swapon: hold");
	204
	205	/* Mark this vnode as being used for swapfile */
	206	SET(vp->v_flag, VSWAP);
	207
	208	/*
	209	* take an extra reference on the vnode to keep
	210	* vnreclaim() away from this vnode.
	211	*/
	212	VREF(vp);
	213
	214	/* Hold on to the namei reference to the paging file vnode */
	215	vp = 0;
	216
	217	swapon_bailout:
	218	if (vp) {
	219	vrele(vp);
	220	}
1c79356b A	221	(void) thread_funnel_set(kernel_flock, FALSE);
	222	return(error);
	223	}
	224
	225	/*
	226	* Routine: macx_swapoff
	227	* Function:
	228	* Syscall interface to remove a file from backing store
	229	*/
	230	int
	231	macx_swapoff(
	232	char *filename,
	233	int flags)
	234	{
	235	kern_return_t kr;
	236	mach_port_t backing_store;
	237
	238	struct vnode *vp = 0;
	239	struct nameidata nd, *ndp;
	240	struct proc *p = current_proc();
	241	int i;
	242	int error;
	243	boolean_t funnel_state;
	244
	245	funnel_state = thread_funnel_set(kernel_flock, TRUE);
	246	backing_store = NULL;
	247	ndp = &nd;
	248
	249	if ((error = suser(p->p_ucred, &p->p_acflag)))
	250	goto swapoff_bailout;
	251
1c79356b A	252	/*
	253	* Get the vnode for the paging area.
	254	*/
	255	NDINIT(ndp, LOOKUP, FOLLOW \| LOCKLEAF, UIO_USERSPACE,
	256	filename, p);
	257
	258	if ((error = namei(ndp)))
	259	goto swapoff_bailout;
	260	vp = ndp->ni_vp;
	261
	262	if (vp->v_type != VREG) {
	263	error = EINVAL;
	264	VOP_UNLOCK(vp, 0, p);
	265	goto swapoff_bailout;
	266	}
	267
	268	for(i = 0; i < MAX_BACKING_STORE; i++) {
	269	if(bs_port_table[i].vp == vp) {
	270	backing_store;
	271	break;
	272	}
	273	}
	274	if (i == MAX_BACKING_STORE) {
	275	error = EINVAL;
	276	VOP_UNLOCK(vp, 0, p);
	277	goto swapoff_bailout;
	278	}
	279	backing_store = (mach_port_t)bs_port_table[i].bs;
	280
	281	VOP_UNLOCK(vp, 0, p);
	282	kr = default_pager_backing_store_delete(backing_store);
	283	switch (kr) {
	284	case KERN_SUCCESS:
	285	error = 0;
	286	bs_port_table[i].vp = 0;
	287	ubc_rele(vp);
	288	/* This vnode is no longer used for swapfile */
	289	CLR(vp->v_flag, VSWAP);
	290
	291	/* get rid of macx_swapon() namei() reference */
	292	vrele(vp);
	293
	294	/* get rid of macx_swapon() "extra" reference */
	295	vrele(vp);
	296	break;
	297	case KERN_FAILURE:
	298	error = EAGAIN;
	299	break;
	300	default:
	301	error = EAGAIN;
	302	break;
	303	}
	304
	305	swapoff_bailout:
	306	/* get rid of macx_swapoff() namei() reference */
	307	if (vp)
	308	vrele(vp);
	309
1c79356b A	310	(void) thread_funnel_set(kernel_flock, FALSE);
	311	return(error);
	312	}