2 * Copyright (c) 2004 Poul-Henning Kamp
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * Architectural notes:
32 * bufobj is a new object which is what buffers hang from in the buffer
35 * This used to be vnodes, but we need non-vnode code to be able
36 * to use the buffer cache as well, specifically geom classes like gbde,
39 * All vnodes will contain a bufobj initially, but down the road we may
40 * want to only allocate bufobjs when they are needed. There could be a
41 * large number of vnodes in the system which wouldn't need a bufobj during
44 * The exact relationship to the vmobject is not determined at this point,
45 * it may in fact be that we find them to be two sides of the same object
46 * once things starts to crystalize.
49 #ifndef _SYS_BUFOBJ_H_
50 #define _SYS_BUFOBJ_H_
52 #if defined(_KERNEL) || defined(_KVM_VNODE)
54 #include <sys/queue.h>
55 #include <sys/_lock.h>
56 #include <sys/_rwlock.h>
57 #include <sys/_pctrie.h>
62 extern struct buf_ops buf_ops_bio;
64 TAILQ_HEAD(buflists, buf);
66 /* A Buffer splay list */
68 struct buflists bv_hd; /* Sorted blocklist */
69 struct pctrie bv_root; /* Buf trie */
70 int bv_cnt; /* Number of buffers */
73 typedef void b_strategy_t(struct bufobj *, struct buf *);
74 typedef int b_write_t(struct buf *);
75 typedef int b_sync_t(struct bufobj *, int waitfor);
76 typedef void b_bdflush_t(struct bufobj *, struct buf *);
81 b_strategy_t *bop_strategy;
83 b_bdflush_t *bop_bdflush;
86 #define BO_STRATEGY(bo, bp) ((bo)->bo_ops->bop_strategy((bo), (bp)))
87 #define BO_SYNC(bo, w) ((bo)->bo_ops->bop_sync((bo), (w)))
88 #define BO_WRITE(bo, bp) ((bo)->bo_ops->bop_write((bp)))
89 #define BO_BDFLUSH(bo, bp) ((bo)->bo_ops->bop_bdflush((bo), (bp)))
92 struct rwlock bo_lock; /* Lock which protects "i" things */
93 struct buf_ops *bo_ops; /* - Buffer operations */
94 struct vm_object *bo_object; /* v Place to store VM object */
95 LIST_ENTRY(bufobj) bo_synclist; /* S dirty vnode list */
96 void *bo_private; /* private pointer */
97 struct vnode *__bo_vnode; /*
98 * XXX: This vnode pointer is here
99 * XXX: only to keep the syncer working
102 struct bufv bo_clean; /* i Clean buffers */
103 struct bufv bo_dirty; /* i Dirty buffers */
104 long bo_numoutput; /* i Writes in progress */
105 u_int bo_flag; /* i Flags */
106 int bo_bsize; /* - Block size for i/o */
110 * XXX BO_ONWORKLST could be replaced with a check for NULL list elements
113 #define BO_ONWORKLST (1 << 0) /* On syncer work-list */
114 #define BO_WWAIT (1 << 1) /* Wait for output to complete */
116 #define BO_LOCKPTR(bo) (&(bo)->bo_lock)
117 #define BO_LOCK(bo) rw_wlock(BO_LOCKPTR((bo)))
118 #define BO_UNLOCK(bo) rw_wunlock(BO_LOCKPTR((bo)))
119 #define BO_RLOCK(bo) rw_rlock(BO_LOCKPTR((bo)))
120 #define BO_RUNLOCK(bo) rw_runlock(BO_LOCKPTR((bo)))
121 #define ASSERT_BO_WLOCKED(bo) rw_assert(BO_LOCKPTR((bo)), RA_WLOCKED)
122 #define ASSERT_BO_LOCKED(bo) rw_assert(BO_LOCKPTR((bo)), RA_LOCKED)
123 #define ASSERT_BO_UNLOCKED(bo) rw_assert(BO_LOCKPTR((bo)), RA_UNLOCKED)
125 void bufobj_wdrop(struct bufobj *bo);
126 void bufobj_wref(struct bufobj *bo);
127 void bufobj_wrefl(struct bufobj *bo);
128 int bufobj_invalbuf(struct bufobj *bo, int flags, int slpflag, int slptimeo);
129 int bufobj_wwait(struct bufobj *bo, int slpflag, int timeo);
130 int bufsync(struct bufobj *bo, int waitfor);
131 void bufbdflush(struct bufobj *bo, struct buf *bp);
133 #endif /* defined(_KERNEL) || defined(_KVM_VNODE) */
134 #endif /* _SYS_BUFOBJ_H_ */