1 /* $NetBSD: buf.c,v 1.12 2004/06/20 22:20:18 jmc Exp $ */
4 * Copyright (c) 2001 Wasabi Systems, Inc.
7 * Written by Luke Mewburn for Wasabi Systems, Inc.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 * must display the following acknowledgement:
19 * This product includes software developed for the NetBSD Project by
20 * Wasabi Systems, Inc.
21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22 * or promote products derived from this software without specific prior
25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC
29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
41 #include <sys/param.h>
52 #include <ufs/ufs/dinode.h>
53 #include <ufs/ffs/fs.h>
56 #include "ffs/ufs_inode.h"
58 extern int sectorsize; /* XXX: from ffs.c & mkfs.c */
60 TAILQ_HEAD(buftailhead,buf) buftail;
63 bread(int fd, struct fs *fs, daddr_t blkno, int size, struct buf **bpp)
71 if (debug & DEBUG_BUF_BREAD)
72 printf("bread: fs %p blkno %lld size %d\n",
73 fs, (long long)blkno, size);
74 *bpp = getblk(fd, fs, blkno, size);
75 offset = (*bpp)->b_blkno * sectorsize; /* XXX */
76 if (debug & DEBUG_BUF_BREAD)
77 printf("bread: bp %p blkno %lld offset %lld bcount %ld\n",
78 (*bpp), (long long)(*bpp)->b_blkno, (long long) offset,
80 if (lseek((*bpp)->b_fd, offset, SEEK_SET) == -1)
81 err(1, "bread: lseek %lld (%lld)",
82 (long long)(*bpp)->b_blkno, (long long)offset);
83 rv = read((*bpp)->b_fd, (*bpp)->b_data, (*bpp)->b_bcount);
84 if (debug & DEBUG_BUF_BREAD)
85 printf("bread: read %ld (%lld) returned %d\n",
86 (*bpp)->b_bcount, (long long)offset, (int)rv);
87 if (rv == -1) /* read error */
88 err(1, "bread: read %ld (%lld) returned %d",
89 (*bpp)->b_bcount, (long long)offset, (int)rv);
90 else if (rv != (*bpp)->b_bcount) /* short read */
91 err(1, "bread: read %ld (%lld) returned %d",
92 (*bpp)->b_bcount, (long long)offset, (int)rv);
98 brelse(struct buf *bp)
102 assert (bp->b_data != NULL);
104 if (bp->b_lblkno < 0) {
106 * XXX don't remove any buffers with negative logical block
107 * numbers (lblkno), so that we retain the mapping
108 * of negative lblkno -> real blkno that ffs_balloc()
111 * if we instead released these buffers, and implemented
112 * ufs_strategy() (and ufs_bmaparray()) and called those
113 * from bread() and bwrite() to convert the lblkno to
114 * a real blkno, we'd add a lot more code & complexity
115 * and reading off disk, for little gain, because this
116 * simple hack works for our purpose.
122 TAILQ_REMOVE(&buftail, bp, b_tailq);
128 bwrite(struct buf *bp)
134 offset = bp->b_blkno * sectorsize; /* XXX */
135 if (debug & DEBUG_BUF_BWRITE)
136 printf("bwrite: bp %p blkno %lld offset %lld bcount %ld\n",
137 bp, (long long)bp->b_blkno, (long long) offset,
139 if (lseek(bp->b_fd, offset, SEEK_SET) == -1)
141 rv = write(bp->b_fd, bp->b_data, bp->b_bcount);
142 if (debug & DEBUG_BUF_BWRITE)
143 printf("bwrite: write %ld (offset %lld) returned %lld\n",
144 bp->b_bcount, (long long)offset, (long long)rv);
145 if (rv == bp->b_bcount)
147 else if (rv == -1) /* write error */
149 else /* short write ? */
159 * XXX this really shouldn't be necessary, but i'm curious to
160 * know why there's still some buffers lying around that
164 if (TAILQ_EMPTY(&buftail))
167 printf("bcleanup: unflushed buffers:\n");
168 TAILQ_FOREACH(bp, &buftail, b_tailq) {
169 printf("\tlblkno %10lld blkno %10lld count %6ld bufsize %6ld\n",
170 (long long)bp->b_lblkno, (long long)bp->b_blkno,
171 bp->b_bcount, bp->b_bufsize);
173 printf("bcleanup: done\n");
177 getblk(int fd, struct fs *fs, daddr_t blkno, int size)
179 static int buftailinitted;
184 if (debug & DEBUG_BUF_GETBLK)
185 printf("getblk: fs %p blkno %lld size %d\n", fs,
186 (long long)blkno, size);
189 if (!buftailinitted) {
190 if (debug & DEBUG_BUF_GETBLK)
191 printf("getblk: initialising tailq\n");
192 TAILQ_INIT(&buftail);
195 TAILQ_FOREACH(bp, &buftail, b_tailq) {
196 if (bp->b_lblkno != blkno)
202 if ((bp = calloc(1, sizeof(struct buf))) == NULL)
203 err(1, "getblk: calloc");
206 bp->b_blkno = bp->b_lblkno = blkno;
210 TAILQ_INSERT_HEAD(&buftail, bp, b_tailq);
213 if (bp->b_data == NULL || bp->b_bcount > bp->b_bufsize) {
214 n = realloc(bp->b_data, size);
216 err(1, "getblk: realloc b_data %ld", bp->b_bcount);
218 bp->b_bufsize = size;