xref: /onnv-gate/usr/src/uts/common/sys/buf.h (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24*0Sstevel@tonic-gate  * Use is subject to license terms.
25*0Sstevel@tonic-gate  */
26*0Sstevel@tonic-gate 
27*0Sstevel@tonic-gate /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
28*0Sstevel@tonic-gate /*	  All Rights Reserved  	*/
29*0Sstevel@tonic-gate 
30*0Sstevel@tonic-gate /*
31*0Sstevel@tonic-gate  * University Copyright- Copyright (c) 1982, 1986, 1988
32*0Sstevel@tonic-gate  * The Regents of the University of California
33*0Sstevel@tonic-gate  * All Rights Reserved
34*0Sstevel@tonic-gate  *
35*0Sstevel@tonic-gate  * University Acknowledgment- Portions of this document are derived from
36*0Sstevel@tonic-gate  * software developed by the University of California, Berkeley, and its
37*0Sstevel@tonic-gate  * contributors.
38*0Sstevel@tonic-gate  */
39*0Sstevel@tonic-gate 
40*0Sstevel@tonic-gate #ifndef _SYS_BUF_H
41*0Sstevel@tonic-gate #define	_SYS_BUF_H
42*0Sstevel@tonic-gate 
43*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
44*0Sstevel@tonic-gate 
45*0Sstevel@tonic-gate #include <sys/types32.h>
46*0Sstevel@tonic-gate #include <sys/t_lock.h>
47*0Sstevel@tonic-gate #include <sys/kstat.h>
48*0Sstevel@tonic-gate 
49*0Sstevel@tonic-gate #ifdef	__cplusplus
50*0Sstevel@tonic-gate extern "C" {
51*0Sstevel@tonic-gate #endif
52*0Sstevel@tonic-gate 
53*0Sstevel@tonic-gate /*
54*0Sstevel@tonic-gate  *	Each buffer in the pool is usually doubly linked into 2 lists:
55*0Sstevel@tonic-gate  *	the device with which it is currently associated (always)
56*0Sstevel@tonic-gate  *	and also on a list of blocks available for allocation
57*0Sstevel@tonic-gate  *	for other use (usually).
58*0Sstevel@tonic-gate  *	The latter list is kept in last-used order, and the two
59*0Sstevel@tonic-gate  *	lists are doubly linked to make it easy to remove
60*0Sstevel@tonic-gate  *	a buffer from one list when it was found by
61*0Sstevel@tonic-gate  *	looking through the other.
62*0Sstevel@tonic-gate  *	A buffer is on the available list, and is liable
63*0Sstevel@tonic-gate  *	to be reassigned to another disk block, if and only
64*0Sstevel@tonic-gate  *	if it is not marked BUSY.  When a buffer is busy, the
65*0Sstevel@tonic-gate  *	available-list pointers can be used for other purposes.
66*0Sstevel@tonic-gate  *	Most drivers use the forward ptr as a link in their I/O active queue.
67*0Sstevel@tonic-gate  *	A buffer header contains all the information required to perform I/O.
68*0Sstevel@tonic-gate  *	Most of the routines which manipulate these things are in bio.c.
69*0Sstevel@tonic-gate  *
70*0Sstevel@tonic-gate  *	There are a number of locks associated with the buffer management
71*0Sstevel@tonic-gate  *	system.
72*0Sstevel@tonic-gate  *	hbuf.b_lock:	protects hash chains, buffer hdr freelists
73*0Sstevel@tonic-gate  *			and delayed write freelist
74*0Sstevel@tonic-gate  *	bfree_lock;	protects the bfreelist structure
75*0Sstevel@tonic-gate  *	bhdr_lock:	protects the free header list
76*0Sstevel@tonic-gate  *	blist_lock:	protects b_list fields
77*0Sstevel@tonic-gate  *	buf.b_sem:	protects all remaining members in the buf struct
78*0Sstevel@tonic-gate  *	buf.b_io:	I/O synchronization variable
79*0Sstevel@tonic-gate  *
80*0Sstevel@tonic-gate  *	A buffer header is never "locked" (b_sem) when it is on
81*0Sstevel@tonic-gate  *	a "freelist" (bhdrlist or bfreelist avail lists).
82*0Sstevel@tonic-gate  */
83*0Sstevel@tonic-gate typedef struct	buf {
84*0Sstevel@tonic-gate 	int	b_flags;		/* see defines below */
85*0Sstevel@tonic-gate 	struct buf *b_forw;		/* headed by d_tab of conf.c */
86*0Sstevel@tonic-gate 	struct buf *b_back;		/*  "  */
87*0Sstevel@tonic-gate 	struct buf *av_forw;		/* position on free list, */
88*0Sstevel@tonic-gate 	struct buf *av_back;		/* if not BUSY */
89*0Sstevel@tonic-gate 	o_dev_t	b_dev;			/* OLD major+minor device name */
90*0Sstevel@tonic-gate 	size_t b_bcount;		/* transfer count */
91*0Sstevel@tonic-gate 	union {
92*0Sstevel@tonic-gate 		caddr_t b_addr;		/* low order core address */
93*0Sstevel@tonic-gate 		struct fs *b_fs;	/* superblocks */
94*0Sstevel@tonic-gate 		struct cg *b_cg;	/* UFS cylinder group block */
95*0Sstevel@tonic-gate 		struct dinode *b_dino;	/* UFS ilist */
96*0Sstevel@tonic-gate 		daddr32_t *b_daddr;	/* disk blocks */
97*0Sstevel@tonic-gate 	} b_un;
98*0Sstevel@tonic-gate 
99*0Sstevel@tonic-gate 	lldaddr_t	_b_blkno;	/* block # on device (union) */
100*0Sstevel@tonic-gate #define	b_lblkno	_b_blkno._f
101*0Sstevel@tonic-gate #ifdef _LP64
102*0Sstevel@tonic-gate #define	b_blkno		_b_blkno._f
103*0Sstevel@tonic-gate #else
104*0Sstevel@tonic-gate #define	b_blkno		_b_blkno._p._l
105*0Sstevel@tonic-gate #endif /* _LP64 */
106*0Sstevel@tonic-gate 
107*0Sstevel@tonic-gate 	char	b_obs1;			/* obsolete */
108*0Sstevel@tonic-gate 	size_t	b_resid;		/* words not transferred after error */
109*0Sstevel@tonic-gate 	clock_t	b_start;		/* request start time */
110*0Sstevel@tonic-gate 	struct  proc  *b_proc;		/* process doing physical or swap I/O */
111*0Sstevel@tonic-gate 	struct	page  *b_pages;		/* page list for PAGEIO */
112*0Sstevel@tonic-gate 	clock_t b_obs2;			/* obsolete */
113*0Sstevel@tonic-gate 	/* Begin new stuff */
114*0Sstevel@tonic-gate #define	b_actf	av_forw
115*0Sstevel@tonic-gate #define	b_actl	av_back
116*0Sstevel@tonic-gate #define	b_active b_bcount
117*0Sstevel@tonic-gate #define	b_errcnt b_resid
118*0Sstevel@tonic-gate 	size_t	b_bufsize;		/* size of allocated buffer */
119*0Sstevel@tonic-gate 	int	(*b_iodone)(struct buf *);	/* function called by iodone */
120*0Sstevel@tonic-gate 	struct	vnode *b_vp;		/* vnode associated with block */
121*0Sstevel@tonic-gate 	struct 	buf *b_chain;		/* chain together all buffers here */
122*0Sstevel@tonic-gate 	int	b_obs3;			/* obsolete */
123*0Sstevel@tonic-gate 	int	b_error;		/* expanded error field */
124*0Sstevel@tonic-gate 	void	*b_private;		/* "opaque" driver private area */
125*0Sstevel@tonic-gate 	dev_t	b_edev;			/* expanded dev field */
126*0Sstevel@tonic-gate 	ksema_t	b_sem;			/* Exclusive access to buf */
127*0Sstevel@tonic-gate 	ksema_t	b_io;			/* I/O Synchronization */
128*0Sstevel@tonic-gate 	struct buf *b_list;		/* List of potential B_DELWRI bufs */
129*0Sstevel@tonic-gate 	struct page **b_shadow;		/* shadow page list */
130*0Sstevel@tonic-gate 	void	*b_dip;			/* device info pointer */
131*0Sstevel@tonic-gate 	struct vnode *b_file;		/* file associated with this buffer */
132*0Sstevel@tonic-gate 	offset_t b_offset;		/* offset in file assoc. with buffer */
133*0Sstevel@tonic-gate } buf_t;
134*0Sstevel@tonic-gate 
135*0Sstevel@tonic-gate /*
136*0Sstevel@tonic-gate  * Bufhd structures used at the head of the hashed buffer queues.
137*0Sstevel@tonic-gate  * We only need seven words for this, so this abbreviated
138*0Sstevel@tonic-gate  * definition saves some space.
139*0Sstevel@tonic-gate  */
140*0Sstevel@tonic-gate struct diskhd {
141*0Sstevel@tonic-gate 	int	b_flags;		/* not used, needed for consistency */
142*0Sstevel@tonic-gate 	struct buf *b_forw, *b_back;	/* queue of unit queues */
143*0Sstevel@tonic-gate 	struct buf *av_forw, *av_back;	/* queue of bufs for this unit */
144*0Sstevel@tonic-gate 	o_dev_t	b_dev;			/* OLD major+minor device name */
145*0Sstevel@tonic-gate 	size_t b_bcount;		/* transfer count */
146*0Sstevel@tonic-gate };
147*0Sstevel@tonic-gate 
148*0Sstevel@tonic-gate 
149*0Sstevel@tonic-gate /*
150*0Sstevel@tonic-gate  * Statistics on the buffer cache
151*0Sstevel@tonic-gate  */
152*0Sstevel@tonic-gate struct biostats {
153*0Sstevel@tonic-gate 	kstat_named_t	bio_lookup;	/* requests to assign buffer */
154*0Sstevel@tonic-gate 	kstat_named_t	bio_hit;	/* buffer already associated with blk */
155*0Sstevel@tonic-gate 	kstat_named_t	bio_bufwant;	/* kmem_allocs NOSLEEP failed new buf */
156*0Sstevel@tonic-gate 	kstat_named_t	bio_bufwait;	/* kmem_allocs with KM_SLEEP for buf */
157*0Sstevel@tonic-gate 	kstat_named_t	bio_bufbusy;	/* buffer locked by someone else */
158*0Sstevel@tonic-gate 	kstat_named_t	bio_bufdup;	/* duplicate buffer found for block */
159*0Sstevel@tonic-gate };
160*0Sstevel@tonic-gate 
161*0Sstevel@tonic-gate /*
162*0Sstevel@tonic-gate  * These flags are kept in b_flags.
163*0Sstevel@tonic-gate  * The first group is part of the DDI
164*0Sstevel@tonic-gate  */
165*0Sstevel@tonic-gate #define	B_BUSY		0x0001	/* not on av_forw/back list */
166*0Sstevel@tonic-gate #define	B_DONE		0x0002	/* transaction finished */
167*0Sstevel@tonic-gate #define	B_ERROR		0x0004	/* transaction aborted */
168*0Sstevel@tonic-gate #define	B_PAGEIO	0x0010	/* do I/O to pages on bp->p_pages */
169*0Sstevel@tonic-gate #define	B_PHYS		0x0020	/* Physical IO potentially using UNIBUS map */
170*0Sstevel@tonic-gate #define	B_READ		0x0040	/* read when I/O occurs */
171*0Sstevel@tonic-gate #define	B_WRITE		0x0100	/* non-read pseudo-flag */
172*0Sstevel@tonic-gate 
173*0Sstevel@tonic-gate /* Not part of the DDI */
174*0Sstevel@tonic-gate #define	B_WANTED	0x0080		/* issue wakeup when BUSY goes off */
175*0Sstevel@tonic-gate #define	B_AGE		0x000200	/* delayed write for correct aging */
176*0Sstevel@tonic-gate #define	B_ASYNC		0x000400	/* don't wait for I/O completion */
177*0Sstevel@tonic-gate #define	B_DELWRI	0x000800	/* delayed write-wait til buf needed */
178*0Sstevel@tonic-gate #define	B_STALE		0x001000	/* on av_* list; invalid contents */
179*0Sstevel@tonic-gate #define	B_DONTNEED	0x002000	/* after write, need not be cached */
180*0Sstevel@tonic-gate #define	B_REMAPPED	0x004000	/* buffer is kernel addressable */
181*0Sstevel@tonic-gate #define	B_FREE		0x008000	/* free page when done */
182*0Sstevel@tonic-gate #define	B_INVAL		0x010000	/* does not contain valid info  */
183*0Sstevel@tonic-gate #define	B_FORCE		0x020000	/* semi-permanent removal from cache */
184*0Sstevel@tonic-gate #define	B_NOCACHE	0x080000 	/* don't cache block when released */
185*0Sstevel@tonic-gate #define	B_TRUNC		0x100000	/* truncate page without I/O */
186*0Sstevel@tonic-gate #define	B_SHADOW	0x200000	/* is b_shadow field valid? */
187*0Sstevel@tonic-gate #define	B_RETRYWRI	0x400000	/* retry write til works or bfinval */
188*0Sstevel@tonic-gate #define	B_FAILFAST	0x1000000	/* Fail promptly if device goes away */
189*0Sstevel@tonic-gate #define	B_STARTED	0x2000000	/* io:::start probe called for buf */
190*0Sstevel@tonic-gate #define	B_ABRWRITE	0x4000000	/* Application based recovery active */
191*0Sstevel@tonic-gate 
192*0Sstevel@tonic-gate /*
193*0Sstevel@tonic-gate  * Insq/Remq for the buffer hash lists.
194*0Sstevel@tonic-gate  */
195*0Sstevel@tonic-gate #define	bremhash(bp) { \
196*0Sstevel@tonic-gate 	ASSERT((bp)->b_forw != NULL); \
197*0Sstevel@tonic-gate 	ASSERT((bp)->b_back != NULL); \
198*0Sstevel@tonic-gate 	(bp)->b_back->b_forw = (bp)->b_forw; \
199*0Sstevel@tonic-gate 	(bp)->b_forw->b_back = (bp)->b_back; \
200*0Sstevel@tonic-gate 	(bp)->b_forw = (bp)->b_back = NULL; \
201*0Sstevel@tonic-gate }
202*0Sstevel@tonic-gate #define	binshash(bp, dp) { \
203*0Sstevel@tonic-gate 	ASSERT((bp)->b_forw == NULL); \
204*0Sstevel@tonic-gate 	ASSERT((bp)->b_back == NULL); \
205*0Sstevel@tonic-gate 	ASSERT((dp)->b_forw != NULL); \
206*0Sstevel@tonic-gate 	ASSERT((dp)->b_back != NULL); \
207*0Sstevel@tonic-gate 	(bp)->b_forw = (dp)->b_forw; \
208*0Sstevel@tonic-gate 	(bp)->b_back = (dp); \
209*0Sstevel@tonic-gate 	(dp)->b_forw->b_back = (bp); \
210*0Sstevel@tonic-gate 	(dp)->b_forw = (bp); \
211*0Sstevel@tonic-gate }
212*0Sstevel@tonic-gate 
213*0Sstevel@tonic-gate 
214*0Sstevel@tonic-gate /*
215*0Sstevel@tonic-gate  * The hash structure maintains two lists:
216*0Sstevel@tonic-gate  *
217*0Sstevel@tonic-gate  * 	1) The hash list of buffers (b_forw & b_back)
218*0Sstevel@tonic-gate  *	2) The LRU free list of buffers on this hash bucket (av_forw & av_back)
219*0Sstevel@tonic-gate  *
220*0Sstevel@tonic-gate  * The dwbuf structure keeps a list of delayed write buffers per hash bucket
221*0Sstevel@tonic-gate  * hence there are exactly the same number of dwbuf structures as there are
222*0Sstevel@tonic-gate  * the hash buckets (hbuf structures) in the system.
223*0Sstevel@tonic-gate  *
224*0Sstevel@tonic-gate  * The number of buffers on the freelist may not be equal to the number of
225*0Sstevel@tonic-gate  * buffers on the hash list. That is because when buffers are busy they are
226*0Sstevel@tonic-gate  * taken off the freelist but not off the hash list. "b_length" field keeps
227*0Sstevel@tonic-gate  * track of the number of free buffers (including delayed writes ones) on
228*0Sstevel@tonic-gate  * the hash bucket. The "b_lock" mutex protects the free list as well as
229*0Sstevel@tonic-gate  * the hash list. It also protects the counter "b_length".
230*0Sstevel@tonic-gate  *
231*0Sstevel@tonic-gate  * Enties b_forw, b_back, av_forw & av_back must be at the same offset
232*0Sstevel@tonic-gate  * as the ones in buf structure.
233*0Sstevel@tonic-gate  */
234*0Sstevel@tonic-gate struct	hbuf {
235*0Sstevel@tonic-gate 	int	b_flags;
236*0Sstevel@tonic-gate 
237*0Sstevel@tonic-gate 	struct	buf	*b_forw;	/* hash list forw pointer */
238*0Sstevel@tonic-gate 	struct	buf	*b_back;	/* hash list back pointer */
239*0Sstevel@tonic-gate 
240*0Sstevel@tonic-gate 	struct	buf	*av_forw;	/* free list forw pointer */
241*0Sstevel@tonic-gate 	struct	buf	*av_back;	/* free list back pointer */
242*0Sstevel@tonic-gate 
243*0Sstevel@tonic-gate 	int		b_length;	/* # of entries on free list */
244*0Sstevel@tonic-gate 	kmutex_t	b_lock;		/* lock to protect this structure */
245*0Sstevel@tonic-gate };
246*0Sstevel@tonic-gate 
247*0Sstevel@tonic-gate 
248*0Sstevel@tonic-gate /*
249*0Sstevel@tonic-gate  * The delayed list pointer entries should match with the buf strcuture.
250*0Sstevel@tonic-gate  */
251*0Sstevel@tonic-gate struct	dwbuf {
252*0Sstevel@tonic-gate 	int	b_flags;		/* not used */
253*0Sstevel@tonic-gate 
254*0Sstevel@tonic-gate 	struct	buf	*b_forw;	/* not used */
255*0Sstevel@tonic-gate 	struct	buf	*b_back;	/* not used */
256*0Sstevel@tonic-gate 
257*0Sstevel@tonic-gate 	struct	buf	*av_forw;	/* delayed write forw pointer */
258*0Sstevel@tonic-gate 	struct	buf	*av_back;	/* delayed write back pointer */
259*0Sstevel@tonic-gate };
260*0Sstevel@tonic-gate 
261*0Sstevel@tonic-gate 
262*0Sstevel@tonic-gate /*
263*0Sstevel@tonic-gate  * Unlink a buffer from the available (free or delayed write) list and mark
264*0Sstevel@tonic-gate  * it busy (internal interface).
265*0Sstevel@tonic-gate  */
266*0Sstevel@tonic-gate #define	notavail(bp) \
267*0Sstevel@tonic-gate {\
268*0Sstevel@tonic-gate 	ASSERT(SEMA_HELD(&bp->b_sem)); \
269*0Sstevel@tonic-gate 	ASSERT((bp)->av_forw != NULL); \
270*0Sstevel@tonic-gate 	ASSERT((bp)->av_back != NULL); \
271*0Sstevel@tonic-gate 	ASSERT((bp)->av_forw != (bp)); \
272*0Sstevel@tonic-gate 	ASSERT((bp)->av_back != (bp)); \
273*0Sstevel@tonic-gate 	(bp)->av_back->av_forw = (bp)->av_forw; \
274*0Sstevel@tonic-gate 	(bp)->av_forw->av_back = (bp)->av_back; \
275*0Sstevel@tonic-gate 	(bp)->b_flags |= B_BUSY; \
276*0Sstevel@tonic-gate 	(bp)->av_forw = (bp)->av_back = NULL; \
277*0Sstevel@tonic-gate }
278*0Sstevel@tonic-gate 
279*0Sstevel@tonic-gate #if defined(_KERNEL)
280*0Sstevel@tonic-gate /*
281*0Sstevel@tonic-gate  * Macros to avoid the extra function call needed for binary compat.
282*0Sstevel@tonic-gate  *
283*0Sstevel@tonic-gate  * B_RETRYWRI is not included in clear_flags for BWRITE(), BWRITE2(),
284*0Sstevel@tonic-gate  * or brwrite() so that the retry operation is persistent until the
285*0Sstevel@tonic-gate  * write either succeeds or the buffer is bfinval()'d.
286*0Sstevel@tonic-gate  *
287*0Sstevel@tonic-gate  */
288*0Sstevel@tonic-gate #define	BREAD(dev, blkno, bsize) \
289*0Sstevel@tonic-gate 	bread_common(/* ufsvfsp */ NULL, dev, blkno, bsize)
290*0Sstevel@tonic-gate 
291*0Sstevel@tonic-gate #define	BWRITE(bp) \
292*0Sstevel@tonic-gate 	bwrite_common(/* ufsvfsp */ NULL, bp, /* force_wait */ 0, \
293*0Sstevel@tonic-gate 		/* do_relse */ 1, \
294*0Sstevel@tonic-gate 		/* clear_flags */ (B_READ | B_DONE | B_ERROR | B_DELWRI))
295*0Sstevel@tonic-gate 
296*0Sstevel@tonic-gate #define	BWRITE2(bp) \
297*0Sstevel@tonic-gate 	bwrite_common(/* ufsvfsp */ NULL, bp, /* force_wait */ 1, \
298*0Sstevel@tonic-gate 		/* do_relse */ 0, \
299*0Sstevel@tonic-gate 		/* clear_flags */ (B_READ | B_DONE | B_ERROR | B_DELWRI))
300*0Sstevel@tonic-gate 
301*0Sstevel@tonic-gate #define	GETBLK(dev, blkno, bsize) \
302*0Sstevel@tonic-gate 	getblk_common(/* ufsvfsp */ NULL, dev, blkno, bsize, /* errflg */ 0)
303*0Sstevel@tonic-gate 
304*0Sstevel@tonic-gate 
305*0Sstevel@tonic-gate /*
306*0Sstevel@tonic-gate  * Macros for new retry write interfaces.
307*0Sstevel@tonic-gate  */
308*0Sstevel@tonic-gate 
309*0Sstevel@tonic-gate /*
310*0Sstevel@tonic-gate  * Same as bdwrite() except write failures are retried.
311*0Sstevel@tonic-gate  */
312*0Sstevel@tonic-gate #define	bdrwrite(bp) { \
313*0Sstevel@tonic-gate 	(bp)->b_flags |= B_RETRYWRI; \
314*0Sstevel@tonic-gate 	bdwrite((bp)); \
315*0Sstevel@tonic-gate }
316*0Sstevel@tonic-gate 
317*0Sstevel@tonic-gate /*
318*0Sstevel@tonic-gate  * Same as bwrite() except write failures are retried.
319*0Sstevel@tonic-gate  */
320*0Sstevel@tonic-gate #define	brwrite(bp) { \
321*0Sstevel@tonic-gate 	(bp)->b_flags |= B_RETRYWRI; \
322*0Sstevel@tonic-gate 	bwrite_common((bp), /* force_wait */ 0, /* do_relse */ 1, \
323*0Sstevel@tonic-gate 		/* clear_flags */ (B_READ | B_DONE | B_ERROR | B_DELWRI)); \
324*0Sstevel@tonic-gate }
325*0Sstevel@tonic-gate 
326*0Sstevel@tonic-gate extern struct hbuf	*hbuf;		/* Hash table */
327*0Sstevel@tonic-gate extern struct dwbuf	*dwbuf;		/* delayed write hash table */
328*0Sstevel@tonic-gate extern struct buf	*buf;		/* The buffer pool itself */
329*0Sstevel@tonic-gate extern struct buf	bfreelist;	/* head of available list */
330*0Sstevel@tonic-gate 
331*0Sstevel@tonic-gate extern void (*bio_lufs_strategy)(void *, buf_t *);	/* UFS Logging */
332*0Sstevel@tonic-gate extern void (*bio_snapshot_strategy)(void *, buf_t *);	/* UFS snapshots */
333*0Sstevel@tonic-gate 
334*0Sstevel@tonic-gate int	bcheck(dev_t, struct buf *);
335*0Sstevel@tonic-gate int	iowait(struct buf *);
336*0Sstevel@tonic-gate int	hash2ints(int x, int y);
337*0Sstevel@tonic-gate int	bio_busy(int);
338*0Sstevel@tonic-gate int	biowait(struct buf *);
339*0Sstevel@tonic-gate int	biomodified(struct buf *);
340*0Sstevel@tonic-gate int	geterror(struct buf *);
341*0Sstevel@tonic-gate void	minphys(struct buf *);
342*0Sstevel@tonic-gate /*
343*0Sstevel@tonic-gate  * ufsvfsp is declared as a void * to avoid having everyone that uses
344*0Sstevel@tonic-gate  * this header file include sys/fs/ufs_inode.h.
345*0Sstevel@tonic-gate  */
346*0Sstevel@tonic-gate void	bwrite_common(void *ufsvfsp, struct buf *, int force_wait,
347*0Sstevel@tonic-gate 	int do_relse, int clear_flags);
348*0Sstevel@tonic-gate void	bwrite(struct buf *);
349*0Sstevel@tonic-gate void	bwrite2(struct buf *);
350*0Sstevel@tonic-gate void	bdwrite(struct buf *);
351*0Sstevel@tonic-gate void	bawrite(struct buf *);
352*0Sstevel@tonic-gate void	brelse(struct buf *);
353*0Sstevel@tonic-gate void	iodone(struct buf *);
354*0Sstevel@tonic-gate void	clrbuf(struct buf *);
355*0Sstevel@tonic-gate void	bflush(dev_t);
356*0Sstevel@tonic-gate void	blkflush(dev_t, daddr_t);
357*0Sstevel@tonic-gate void	binval(dev_t);
358*0Sstevel@tonic-gate int	bfinval(dev_t, int);
359*0Sstevel@tonic-gate void	binit(void);
360*0Sstevel@tonic-gate void	biodone(struct buf *);
361*0Sstevel@tonic-gate void	bioinit(struct buf *);
362*0Sstevel@tonic-gate void	biofini(struct buf *);
363*0Sstevel@tonic-gate void	bp_mapin(struct buf *);
364*0Sstevel@tonic-gate void	*bp_mapin_common(struct buf *, int);
365*0Sstevel@tonic-gate void	bp_mapout(struct buf *);
366*0Sstevel@tonic-gate void	bp_init(size_t, uint_t);
367*0Sstevel@tonic-gate int	bp_color(struct buf *);
368*0Sstevel@tonic-gate void	pageio_done(struct buf *);
369*0Sstevel@tonic-gate struct buf *bread(dev_t, daddr_t, long);
370*0Sstevel@tonic-gate struct buf *bread_common(void *, dev_t, daddr_t, long);
371*0Sstevel@tonic-gate struct buf *breada(dev_t, daddr_t, daddr_t, long);
372*0Sstevel@tonic-gate struct buf *getblk(dev_t, daddr_t, long);
373*0Sstevel@tonic-gate struct buf *getblk_common(void *, dev_t, daddr_t, long, int);
374*0Sstevel@tonic-gate struct buf *ngeteblk(long);
375*0Sstevel@tonic-gate struct buf *geteblk(void);
376*0Sstevel@tonic-gate struct buf *pageio_setup(struct page *, size_t, struct vnode *, int);
377*0Sstevel@tonic-gate void bioerror(struct buf *bp, int error);
378*0Sstevel@tonic-gate void bioreset(struct buf *bp);
379*0Sstevel@tonic-gate struct buf *bioclone(struct buf *, off_t, size_t, dev_t, daddr_t,
380*0Sstevel@tonic-gate 	int (*)(struct buf *), struct buf *, int);
381*0Sstevel@tonic-gate size_t	biosize(void);
382*0Sstevel@tonic-gate #endif	/* defined(_KERNEL) */
383*0Sstevel@tonic-gate 
384*0Sstevel@tonic-gate #ifdef	__cplusplus
385*0Sstevel@tonic-gate }
386*0Sstevel@tonic-gate #endif
387*0Sstevel@tonic-gate 
388*0Sstevel@tonic-gate #endif	/* _SYS_BUF_H */
389