[apple/xnu.git] / bsd / sys / buf.h

/*
 * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This 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 OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
 * Copyright (c) 1982, 1986, 1989, 1993
 *	The Regents of the University of California.  All rights reserved.
 * (c) UNIX System Laboratories, Inc.
 * All or some portions of this file are derived from material licensed
 * to the University of California by American Telephone and Telegraph
 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
 * the permission of UNIX System Laboratories, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)buf.h	8.9 (Berkeley) 3/30/95
 */

#ifndef _SYS_BUF_H_
#define	_SYS_BUF_H_

#include <sys/cdefs.h>
#include <sys/kernel_types.h>
#include <mach/memory_object_types.h>


#define	B_WRITE		0x00000000	/* Write buffer (pseudo flag). */
#define	B_READ		0x00000001	/* Read buffer. */
#define	B_ASYNC		0x00000002	/* Start I/O, do not wait. */
#define	B_NOCACHE	0x00000004	/* Do not cache block after use. */
#define	B_DELWRI	0x00000008	/* Delay I/O until buffer reused. */
#define	B_LOCKED	0x00000010	/* Locked in core (not reusable). */
#define	B_PHYS		0x00000020	/* I/O to user memory. */
#define B_CLUSTER	0x00000040	/* UPL based I/O generated by cluster layer */
#define	B_PAGEIO	0x00000080	/* Page in/out */
#define	B_META		0x00000100	/* buffer contains meta-data. */
/*
 * make sure to check when adding flags that
 * that the new flags don't overlap the definitions
 * in buf_internal.h
 */

__BEGIN_DECLS

/*
 * mark the buffer associated with buf_t
 * as AGED with respect to the LRU cache
 */
void	buf_markaged(buf_t);

/*
 * mark the buffer associated with buf_t
 * as invalid... on release, it will go
 * directly to the free list
 */
void	buf_markinvalid(buf_t);

/*
 * mark the buffer assoicated with buf_t
 * as a delayed write... 
 */
void	buf_markdelayed(buf_t);

/*
 * mark the buffer associated with buf_t
 * as having been interrupted... EINTR
 */
void	buf_markeintr(buf_t);

/*
 * returns 1 if the buffer associated with buf_t
 * contains valid data... 0 if it does not
 */
int	buf_valid(buf_t);

/*
 * returns 1 if the buffer was already valid
 * in the cache... i.e. no I/O was performed
 * returns 0 otherwise
 */
int	buf_fromcache(buf_t);

/*
 * returns the UPL associated with buf_t
 */
void *	buf_upl(buf_t);

/*
 * returns the offset into the UPL
 * associated with buf_t which is to be
 * used as the base offset for this I/O
 */
uint32_t buf_uploffset(buf_t);

/*
 * returns read credential associated with buf_t
 * a reference is taken which must be explicilty dropped
 */
ucred_t buf_rcred(buf_t);

/*
 * returns write credential associated with buf_t
 * a reference is taken which must be explicilty dropped
 */
ucred_t buf_wcred(buf_t);

/*
 * returns process handle associated with buf_t
 * i.e identity of task that issued the I/O
 */
proc_t	buf_proc(buf_t);

uint32_t buf_dirtyoff(buf_t);
uint32_t buf_dirtyend(buf_t);
void	buf_setdirtyoff(buf_t, uint32_t);
void	buf_setdirtyend(buf_t, uint32_t);

/*
 * return the errno value associated with buf_t
 */
errno_t	buf_error(buf_t);

/*
 * set errno on buf_t
 */
void	buf_seterror(buf_t, errno_t);

/*
 * set specified flags on buf_t
 * B_LOCKED/B_NOCACHE/B_ASYNC/B_READ/B_WRITE/B_PAGEIO
 */
void	buf_setflags(buf_t, int32_t);

/*
 * clear specified flags on buf_t
 * B_LOCKED/B_NOCACHE/B_ASYNC/B_READ/B_WRITE/B_PAGEIO
 */
void	buf_clearflags(buf_t, int32_t);

/*
 * return external flags associated with buf_t
 * B_CLUSTER/B_PHYS/B_LOCKED/B_DELWRI/B_ASYNC/B_READ/B_WRITE/B_META/B_PAGEIO
 */
int32_t	buf_flags(buf_t);

/*
 * clears I/O related flags (both internal and
 * external) associated with buf_t and allows
 * the following to be set...
 * B_READ/B_WRITE/B_ASYNC/B_NOCACHE
 */
void	buf_reset(buf_t, int32_t);

/*
 * insure that the data storage associated with buf_t
 * is addressable
 */
errno_t	buf_map(buf_t, caddr_t *);

/*
 * release our need to have the storage associated
 * with buf_t in an addressable state
 */
errno_t	buf_unmap(buf_t);

/*
 * set driver specific data for buf_t
 */
void 	buf_setdrvdata(buf_t, void *);

/*
 * retrieve driver specific data associated with buf_t
 */
void *	buf_drvdata(buf_t);

/*
 * set fs specific data for buf_t
 */
void 	buf_setfsprivate(buf_t, void *);

/*
 * retrieve driver specific data associated with buf_t
 */
void *	buf_fsprivate(buf_t);

/*
 * retrieve the phsyical block number associated with buf_t
 */
daddr64_t buf_blkno(buf_t);

/*
 * retrieve the logical block number associated with buf_t
 * i.e. the block number derived from the file offset
 */
daddr64_t buf_lblkno(buf_t);

/*
 * set the phsyical block number associated with buf_t
 */
void	buf_setblkno(buf_t, daddr64_t);

/*
 * set the logical block number associated with buf_t
 * i.e. the block number derived from the file offset
 */
void	buf_setlblkno(buf_t, daddr64_t);

/*
 * retrieve the count of valid bytes associated with buf_t
 */
uint32_t buf_count(buf_t);

/*
 * retrieve the size of the data store assoicated with buf_t
 */
uint32_t buf_size(buf_t);

/*
 * retrieve the residual I/O count assoicated with buf_t
 * i.e. number of bytes that have not yet been completed
 */
uint32_t buf_resid(buf_t);

/*
 * set the count of bytes associated with buf_t
 * typically used to set the size of the I/O to be performed
 */
void	buf_setcount(buf_t, uint32_t);

/*
 * set the size of the buffer store associated with buf_t
 * typically used when providing private storage to buf_t
 */
void	buf_setsize(buf_t, uint32_t);

/*
 * set the size in bytes of the unfinished I/O associated with buf_t
 */
void	buf_setresid(buf_t, uint32_t);

/*
 * associate kernel addressable storage with buf_t
 */
void	buf_setdataptr(buf_t, uintptr_t);

/*
 * retrieve pointer to buffer associated with buf_t
 * if non-null, than guaranteed to be kernel addressable
 * size of buffer can be retrieved via buf_size
 * size of valid data can be retrieved via buf_count
 * if NULL, than use buf_map/buf_unmap to manage access to the underlying storage
 */
uintptr_t buf_dataptr(buf_t);

/*
 * return the vnode_t associated with buf_t
 */
vnode_t	buf_vnode(buf_t);

/*
 * assign vnode_t to buf_t... the 
 * device currently associated with
 * but_t is not changed.
 */
void	buf_setvnode(buf_t, vnode_t);

/*
 * return the dev_t associated with buf_t
 */
dev_t	buf_device(buf_t);

/*
 * assign the dev_t associated with vnode_t
 * to buf_t
 */
errno_t	buf_setdevice(buf_t, vnode_t);

errno_t	buf_strategy(vnode_t, void *);

/*
 * flags for buf_invalblkno
 */
#define	BUF_WAIT	0x01

errno_t	buf_invalblkno(vnode_t, daddr64_t, int);


/*
 * return the callback function pointer
 * if the callback is still valid
 * returns NULL if a buffer that was not
 * allocated via buf_alloc is specified
 * or if a callback has not been set or
 * it has already fired...
 */
void * buf_callback(buf_t);

/*
 * assign a one-shot callback function (driven from biodone)
 * to a buf_t allocated via buf_alloc... a caller specified
 * arg is passed to the callback function
 */
errno_t	buf_setcallback(buf_t, void (*)(buf_t, void *), void *);

/*
 * add a upl_t to a buffer allocated via buf_alloc
 * and set the offset into the upl_t (must be page
 * aligned).
 */
errno_t	buf_setupl(buf_t, upl_t, uint32_t);

/*
 * allocate a buf_t that is a clone of the buf_t
 * passed in, but whose I/O range is a subset...
 * if a callback routine is specified, it will
 * be called from buf_biodone with the bp and
 * arg specified.
 * it must be freed via buf_free
 */
buf_t	buf_clone(buf_t, int, int, void (*)(buf_t, void *), void *);

/*
 * allocate a buf_t associated with vnode_t
 * that has NO storage associated with it
 * but is suitable for use in issuing I/Os
 * after storage has been assigned via buf_setdataptr
 * or buf_addupl
 */
buf_t 	buf_alloc(vnode_t);

/*
 * free a buf_t that was allocated via buf_alloc
 * any private storage associated with buf_t is the
 * responsiblity of the caller to release
 */
void	buf_free(buf_t);

/*
 * flags for buf_invalidateblks
 */
#define	BUF_WRITE_DATA	0x0001		/* write data blocks first */
#define	BUF_SKIP_META	0x0002		/* skip over metadata blocks */

int	buf_invalidateblks(vnode_t, int, int, int);
/*
 * flags for buf_flushdirtyblks and buf_iterate
 */
#define BUF_SKIP_NONLOCKED	0x01
#define BUF_SKIP_LOCKED		0x02

void	buf_flushdirtyblks(vnode_t, int, int, char *);
void	buf_iterate(vnode_t, int (*)(buf_t, void *), int, void *);

#define	BUF_RETURNED		0
#define BUF_RETURNED_DONE	1
#define BUF_CLAIMED		2
#define	BUF_CLAIMED_DONE	3

/*
 * zero the storage associated with buf_t
 */
void	buf_clear(buf_t);

errno_t	buf_bawrite(buf_t);
errno_t	buf_bdwrite(buf_t);
errno_t	buf_bwrite(buf_t);

void	buf_biodone(buf_t);
errno_t	buf_biowait(buf_t);
void	buf_brelse(buf_t);

errno_t	buf_bread(vnode_t, daddr64_t, int, ucred_t, buf_t *);
errno_t	buf_breadn(vnode_t, daddr64_t, int, daddr64_t *, int *, int, ucred_t, buf_t *);
errno_t	buf_meta_bread(vnode_t, daddr64_t, int, ucred_t, buf_t *);
errno_t	buf_meta_breadn(vnode_t, daddr64_t, int, daddr64_t *, int *, int, ucred_t, buf_t *);

u_int	minphys(buf_t bp);
int	physio(void (*)(buf_t), buf_t, dev_t, int ,  u_int (*)(buf_t), struct uio *, int );


/*
 * Flags for operation type in getblk()
 */
#define	BLK_READ	0x01	/* buffer for read */
#define	BLK_WRITE	0x02	/* buffer for write */
#define	BLK_META	0x10	/* buffer for metadata */
/*
 * modifier for above flags...  if set, getblk will only return
 * a bp that is already valid... i.e. found in the cache
 */
#define BLK_ONLYVALID	0x80000000
                                  
/* timeout is in msecs */
buf_t	buf_getblk(vnode_t, daddr64_t, int, int, int, int);
buf_t	buf_geteblk(int);

__END_DECLS


/* Macros to clear/set/test flags. */
#define	SET(t, f)	(t) |= (f)
#define	CLR(t, f)	(t) &= ~(f)
#define	ISSET(t, f)	((t) & (f))


#endif /* !_SYS_BUF_H_ */
Commit	Line	Data
1c79356b	1	/*
5d5c5d0d A	2	* Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
5d5c5d0d A	3	*
6601e61a	4	* @APPLE_LICENSE_HEADER_START@
1c79356b	5	*
6601e61a A	6	* The contents of this file constitute Original Code as defined in and
	7	* are subject to the Apple Public Source License Version 1.1 (the
	8	* "License"). You may not use this file except in compliance with the
	9	* License. Please obtain a copy of the License at
	10	* http://www.apple.com/publicsource and read it before using this file.
8f6c56a5	11	*
6601e61a A	12	* This Original Code and all software distributed under the License are
6601e61a A	13	* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
8f6c56a5 A	14	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
8f6c56a5 A	15	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
6601e61a A	16	* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
	17	* License for the specific language governing rights and limitations
	18	* under the License.
8f6c56a5	19	*
6601e61a	20	* @APPLE_LICENSE_HEADER_END@
1c79356b A	21	*/
	22	/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
	23	/*
	24	* Copyright (c) 1982, 1986, 1989, 1993
	25	* The Regents of the University of California. All rights reserved.
	26	* (c) UNIX System Laboratories, Inc.
	27	* All or some portions of this file are derived from material licensed
	28	* to the University of California by American Telephone and Telegraph
	29	* Co. or Unix System Laboratories, Inc. and are reproduced herein with
	30	* the permission of UNIX System Laboratories, Inc.
	31	*
	32	* Redistribution and use in source and binary forms, with or without
	33	* modification, are permitted provided that the following conditions
	34	* are met:
	35	* 1. Redistributions of source code must retain the above copyright
	36	* notice, this list of conditions and the following disclaimer.
	37	* 2. Redistributions in binary form must reproduce the above copyright
	38	* notice, this list of conditions and the following disclaimer in the
	39	* documentation and/or other materials provided with the distribution.
	40	* 3. All advertising materials mentioning features or use of this software
	41	* must display the following acknowledgement:
	42	* This product includes software developed by the University of
	43	* California, Berkeley and its contributors.
	44	* 4. Neither the name of the University nor the names of its contributors
	45	* may be used to endorse or promote products derived from this software
	46	* without specific prior written permission.
	47	*
	48	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	49	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	50	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	51	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	52	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	53	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	54	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	55	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	56	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	57	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	58	* SUCH DAMAGE.
	59	*
	60	* @(#)buf.h 8.9 (Berkeley) 3/30/95
	61	*/
	62
	63	#ifndef _SYS_BUF_H_
	64	#define _SYS_BUF_H_
9bccf70c	65
9bccf70c	66	#include <sys/cdefs.h>
91447636 A	67	#include <sys/kernel_types.h>
	68	#include <mach/memory_object_types.h>
	69
1c79356b	70
1c79356b	71	#define B_WRITE 0x00000000 /* Write buffer (pseudo flag). */
91447636 A	72	#define B_READ 0x00000001 /* Read buffer. */
	73	#define B_ASYNC 0x00000002 /* Start I/O, do not wait. */
	74	#define B_NOCACHE 0x00000004 /* Do not cache block after use. */
	75	#define B_DELWRI 0x00000008 /* Delay I/O until buffer reused. */
	76	#define B_LOCKED 0x00000010 /* Locked in core (not reusable). */
	77	#define B_PHYS 0x00000020 /* I/O to user memory. */
	78	#define B_CLUSTER 0x00000040 /* UPL based I/O generated by cluster layer */
	79	#define B_PAGEIO 0x00000080 /* Page in/out */
	80	#define B_META 0x00000100 /* buffer contains meta-data. */
	81	/*
	82	* make sure to check when adding flags that
	83	* that the new flags don't overlap the definitions
	84	* in buf_internal.h
	85	*/
1c79356b	86
91447636	87	__BEGIN_DECLS
1c79356b	88
91447636 A	89	/*
	90	* mark the buffer associated with buf_t
	91	* as AGED with respect to the LRU cache
	92	*/
	93	void buf_markaged(buf_t);
9bccf70c	94
91447636 A	95	/*
	96	* mark the buffer associated with buf_t
	97	* as invalid... on release, it will go
	98	* directly to the free list
	99	*/
	100	void buf_markinvalid(buf_t);
9bccf70c	101
91447636 A	102	/*
	103	* mark the buffer assoicated with buf_t
	104	* as a delayed write...
	105	*/
	106	void buf_markdelayed(buf_t);
1c79356b A	107
1c79356b A	108	/*
91447636 A	109	* mark the buffer associated with buf_t
91447636 A	110	* as having been interrupted... EINTR
1c79356b	111	*/
91447636	112	void buf_markeintr(buf_t);
1c79356b	113
91447636 A	114	/*
	115	* returns 1 if the buffer associated with buf_t
	116	* contains valid data... 0 if it does not
	117	*/
	118	int buf_valid(buf_t);
1c79356b	119
91447636 A	120	/*
	121	* returns 1 if the buffer was already valid
	122	* in the cache... i.e. no I/O was performed
	123	* returns 0 otherwise
	124	*/
	125	int buf_fromcache(buf_t);
	126
	127	/*
	128	* returns the UPL associated with buf_t
	129	*/
	130	void * buf_upl(buf_t);
	131
	132	/*
	133	* returns the offset into the UPL
	134	* associated with buf_t which is to be
	135	* used as the base offset for this I/O
	136	*/
	137	uint32_t buf_uploffset(buf_t);
	138
	139	/*
	140	* returns read credential associated with buf_t
	141	* a reference is taken which must be explicilty dropped
	142	*/
	143	ucred_t buf_rcred(buf_t);
	144
	145	/*
	146	* returns write credential associated with buf_t
	147	* a reference is taken which must be explicilty dropped
	148	*/
	149	ucred_t buf_wcred(buf_t);
	150
	151	/*
	152	* returns process handle associated with buf_t
	153	* i.e identity of task that issued the I/O
	154	*/
	155	proc_t buf_proc(buf_t);
	156
	157	uint32_t buf_dirtyoff(buf_t);
	158	uint32_t buf_dirtyend(buf_t);
	159	void buf_setdirtyoff(buf_t, uint32_t);
	160	void buf_setdirtyend(buf_t, uint32_t);
	161
	162	/*
	163	* return the errno value associated with buf_t
	164	*/
	165	errno_t buf_error(buf_t);
	166
	167	/*
	168	* set errno on buf_t
	169	*/
	170	void buf_seterror(buf_t, errno_t);
	171
	172	/*
	173	* set specified flags on buf_t
	174	* B_LOCKED/B_NOCACHE/B_ASYNC/B_READ/B_WRITE/B_PAGEIO
	175	*/
	176	void buf_setflags(buf_t, int32_t);
	177
	178	/*
	179	* clear specified flags on buf_t
	180	* B_LOCKED/B_NOCACHE/B_ASYNC/B_READ/B_WRITE/B_PAGEIO
	181	*/
	182	void buf_clearflags(buf_t, int32_t);
	183
184	/*
185	* return external flags associated with buf_t
186	* B_CLUSTER/B_PHYS/B_LOCKED/B_DELWRI/B_ASYNC/B_READ/B_WRITE/B_META/B_PAGEIO
187	*/
188	int32_t buf_flags(buf_t);
189
190	/*
191	* clears I/O related flags (both internal and
192	* external) associated with buf_t and allows
193	* the following to be set...
194	* B_READ/B_WRITE/B_ASYNC/B_NOCACHE
195	*/
196	void buf_reset(buf_t, int32_t);
197
198	/*
199	* insure that the data storage associated with buf_t
200	* is addressable
201	*/
202	errno_t buf_map(buf_t, caddr_t *);
203
204	/*
205	* release our need to have the storage associated
206	* with buf_t in an addressable state
207	*/
208	errno_t buf_unmap(buf_t);
209
210	/*
211	* set driver specific data for buf_t
212	*/
213	void buf_setdrvdata(buf_t, void *);
214
215	/*
216	* retrieve driver specific data associated with buf_t
217	*/
218	void * buf_drvdata(buf_t);
219
220	/*
221	* set fs specific data for buf_t
222	*/
223	void buf_setfsprivate(buf_t, void *);
224
225	/*
226	* retrieve driver specific data associated with buf_t
227	*/
228	void * buf_fsprivate(buf_t);
229
230	/*
231	* retrieve the phsyical block number associated with buf_t
232	*/
233	daddr64_t buf_blkno(buf_t);
234
235	/*
236	* retrieve the logical block number associated with buf_t
237	* i.e. the block number derived from the file offset
238	*/
239	daddr64_t buf_lblkno(buf_t);
240
241	/*
242	* set the phsyical block number associated with buf_t
243	*/
244	void buf_setblkno(buf_t, daddr64_t);
245
246	/*
247	* set the logical block number associated with buf_t
248	* i.e. the block number derived from the file offset
249	*/
250	void buf_setlblkno(buf_t, daddr64_t);
251
252	/*
253	* retrieve the count of valid bytes associated with buf_t
254	*/
255	uint32_t buf_count(buf_t);
256
257	/*
258	* retrieve the size of the data store assoicated with buf_t
259	*/
260	uint32_t buf_size(buf_t);
261
262	/*
263	* retrieve the residual I/O count assoicated with buf_t
264	* i.e. number of bytes that have not yet been completed
265	*/
266	uint32_t buf_resid(buf_t);
267
268	/*
269	* set the count of bytes associated with buf_t
270	* typically used to set the size of the I/O to be performed
271	*/
272	void buf_setcount(buf_t, uint32_t);
273
274	/*
275	* set the size of the buffer store associated with buf_t
276	* typically used when providing private storage to buf_t
277	*/
278	void buf_setsize(buf_t, uint32_t);
279
280	/*
281	* set the size in bytes of the unfinished I/O associated with buf_t
282	*/
283	void buf_setresid(buf_t, uint32_t);
284
285	/*
286	* associate kernel addressable storage with buf_t
287	*/
288	void buf_setdataptr(buf_t, uintptr_t);
289
290	/*
291	* retrieve pointer to buffer associated with buf_t
292	* if non-null, than guaranteed to be kernel addressable
293	* size of buffer can be retrieved via buf_size
294	* size of valid data can be retrieved via buf_count
295	* if NULL, than use buf_map/buf_unmap to manage access to the underlying storage
296	*/
297	uintptr_t buf_dataptr(buf_t);
1c79356b A	298
1c79356b A	299	/*
91447636	300	* return the vnode_t associated with buf_t
1c79356b	301	*/
91447636 A	302	vnode_t buf_vnode(buf_t);
	303
	304	/*
	305	* assign vnode_t to buf_t... the
	306	* device currently associated with
	307	* but_t is not changed.
	308	*/
	309	void buf_setvnode(buf_t, vnode_t);
	310
	311	/*
	312	* return the dev_t associated with buf_t
	313	*/
	314	dev_t buf_device(buf_t);
	315
	316	/*
	317	* assign the dev_t associated with vnode_t
	318	* to buf_t
	319	*/
	320	errno_t buf_setdevice(buf_t, vnode_t);
	321
	322	errno_t buf_strategy(vnode_t, void *);
	323
	324	/*
	325	* flags for buf_invalblkno
	326	*/
	327	#define BUF_WAIT 0x01
	328
	329	errno_t buf_invalblkno(vnode_t, daddr64_t, int);
	330
	331
	332	/*
	333	* return the callback function pointer
	334	* if the callback is still valid
	335	* returns NULL if a buffer that was not
	336	* allocated via buf_alloc is specified
	337	* or if a callback has not been set or
	338	* it has already fired...
	339	*/
	340	void * buf_callback(buf_t);
	341
	342	/*
	343	* assign a one-shot callback function (driven from biodone)
	344	* to a buf_t allocated via buf_alloc... a caller specified
	345	* arg is passed to the callback function
	346	*/
	347	errno_t buf_setcallback(buf_t, void ()(buf_t, void ), void *);
	348
	349	/*
	350	* add a upl_t to a buffer allocated via buf_alloc
	351	* and set the offset into the upl_t (must be page
	352	* aligned).
	353	*/
	354	errno_t buf_setupl(buf_t, upl_t, uint32_t);
	355
	356	/*
	357	* allocate a buf_t that is a clone of the buf_t
	358	* passed in, but whose I/O range is a subset...
	359	* if a callback routine is specified, it will
	360	* be called from buf_biodone with the bp and
	361	* arg specified.
	362	* it must be freed via buf_free
	363	*/
	364	buf_t buf_clone(buf_t, int, int, void ()(buf_t, void ), void *);
	365
366	/*
367	* allocate a buf_t associated with vnode_t
368	* that has NO storage associated with it
369	* but is suitable for use in issuing I/Os
370	* after storage has been assigned via buf_setdataptr
371	* or buf_addupl
372	*/
373	buf_t buf_alloc(vnode_t);
374
375	/*
376	* free a buf_t that was allocated via buf_alloc
377	* any private storage associated with buf_t is the
378	* responsiblity of the caller to release
379	*/
380	void buf_free(buf_t);
381
382	/*
383	* flags for buf_invalidateblks
384	*/
385	#define BUF_WRITE_DATA 0x0001 /* write data blocks first */
386	#define BUF_SKIP_META 0x0002 /* skip over metadata blocks */
387
388	int buf_invalidateblks(vnode_t, int, int, int);
389	/*
390	* flags for buf_flushdirtyblks and buf_iterate
391	*/
392	#define BUF_SKIP_NONLOCKED 0x01
393	#define BUF_SKIP_LOCKED 0x02
394
395	void buf_flushdirtyblks(vnode_t, int, int, char *);
396	void buf_iterate(vnode_t, int ()(buf_t, void ), int, void *);
397
398	#define BUF_RETURNED 0
399	#define BUF_RETURNED_DONE 1
400	#define BUF_CLAIMED 2
401	#define BUF_CLAIMED_DONE 3
402
403	/*
404	* zero the storage associated with buf_t
405	*/
406	void buf_clear(buf_t);
407
408	errno_t buf_bawrite(buf_t);
409	errno_t buf_bdwrite(buf_t);
410	errno_t buf_bwrite(buf_t);
411
412	void buf_biodone(buf_t);
413	errno_t buf_biowait(buf_t);
414	void buf_brelse(buf_t);
415
416	errno_t buf_bread(vnode_t, daddr64_t, int, ucred_t, buf_t *);
417	errno_t buf_breadn(vnode_t, daddr64_t, int, daddr64_t , int , int, ucred_t, buf_t *);
418	errno_t buf_meta_bread(vnode_t, daddr64_t, int, ucred_t, buf_t *);
419	errno_t buf_meta_breadn(vnode_t, daddr64_t, int, daddr64_t , int , int, ucred_t, buf_t *);
420
421	u_int minphys(buf_t bp);
422	int physio(void ()(buf_t), buf_t, dev_t, int , u_int ()(buf_t), struct uio *, int );
423
424
425	/*
426	* Flags for operation type in getblk()
427	*/
428	#define BLK_READ 0x01 /* buffer for read */
429	#define BLK_WRITE 0x02 /* buffer for write */
430	#define BLK_META 0x10 /* buffer for metadata */
431	/*
432	* modifier for above flags... if set, getblk will only return
433	* a bp that is already valid... i.e. found in the cache
434	*/
435	#define BLK_ONLYVALID 0x80000000
436
437	/* timeout is in msecs */
438	buf_t buf_getblk(vnode_t, daddr64_t, int, int, int, int);
439	buf_t buf_geteblk(int);
440
441	__END_DECLS
442
443
444	/* Macros to clear/set/test flags. */
445	#define SET(t, f) (t) \|= (f)
446	#define CLR(t, f) (t) &= ~(f)
447	#define ISSET(t, f) ((t) & (f))
448
1c79356b	449
1c79356b	450	#endif /* !_SYS_BUF_H_ */