xref: /dragonfly/usr.sbin/makefs/ffs/buf.c (revision 4238ce6f)
1 /*	$NetBSD: buf.c,v 1.13 2004/06/20 22:20:18 jmc Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-4-Clause
5  *
6  * Copyright (c) 2001 Wasabi Systems, Inc.
7  * All rights reserved.
8  *
9  * Written by Luke Mewburn for Wasabi Systems, Inc.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *      This product includes software developed for the NetBSD Project by
22  *      Wasabi Systems, Inc.
23  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
24  *    or promote products derived from this software without specific prior
25  *    written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37  * POSSIBILITY OF SUCH DAMAGE.
38  *
39  * $FreeBSD: head/usr.sbin/makefs/ffs/buf.c 336736 2018-07-26 13:33:10Z emaste $
40  */
41 
42 #include <sys/param.h>
43 #include <sys/time.h>
44 
45 #include <assert.h>
46 #include <errno.h>
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50 #include <unistd.h>
51 #include <util.h>
52 
53 #include "makefs.h"
54 #include "buf.h"
55 
56 static TAILQ_HEAD(buftailhead,m_buf) buftail;
57 
58 int
59 bread(struct m_vnode *vp, makefs_daddr_t blkno, int size, struct ucred *u1 __unused,
60     struct m_buf **bpp)
61 {
62 	off_t	offset;
63 	ssize_t	rv;
64 	fsinfo_t *fs = vp->fs;
65 
66 	assert (bpp != NULL);
67 
68 	if (debug & DEBUG_BUF_BREAD)
69 		printf("%s: blkno %lld size %d\n", __func__, (long long)blkno,
70 		    size);
71 	*bpp = getblk(vp, blkno, size, 0, 0, 0);
72 	offset = (off_t)(*bpp)->b_blkno * fs->sectorsize + fs->offset;
73 	if (debug & DEBUG_BUF_BREAD)
74 		printf("%s: blkno %lld offset %lld bcount %ld\n", __func__,
75 		    (long long)(*bpp)->b_blkno, (long long) offset,
76 		    (*bpp)->b_bcount);
77 	if (lseek((*bpp)->b_fs->fd, offset, SEEK_SET) == -1)
78 		err(1, "%s: lseek %lld (%lld)", __func__,
79 		    (long long)(*bpp)->b_blkno, (long long)offset);
80 	rv = read((*bpp)->b_fs->fd, (*bpp)->b_data, (*bpp)->b_bcount);
81 	if (debug & DEBUG_BUF_BREAD)
82 		printf("%s: read %ld (%lld) returned %d\n", __func__,
83 		    (*bpp)->b_bcount, (long long)offset, (int)rv);
84 	if (rv == -1)				/* read error */
85 		err(1, "%s: read %ld (%lld) returned %d", __func__,
86 		    (*bpp)->b_bcount, (long long)offset, (int)rv);
87 	else if (rv != (*bpp)->b_bcount)	/* short read */
88 		err(1, "%s: read %ld (%lld) returned %d", __func__,
89 		    (*bpp)->b_bcount, (long long)offset, (int)rv);
90 	else
91 		return (0);
92 }
93 
94 void
95 brelse(struct m_buf *bp)
96 {
97 
98 	assert (bp != NULL);
99 	assert (bp->b_data != NULL);
100 
101 	if (bp->b_lblkno < 0) {
102 		/*
103 		 * XXX	don't remove any buffers with negative logical block
104 		 *	numbers (lblkno), so that we retain the mapping
105 		 *	of negative lblkno -> real blkno that ffs_balloc()
106 		 *	sets up.
107 		 *
108 		 *	if we instead released these buffers, and implemented
109 		 *	ufs_strategy() (and ufs_bmaparray()) and called those
110 		 *	from bread() and bwrite() to convert the lblkno to
111 		 *	a real blkno, we'd add a lot more code & complexity
112 		 *	and reading off disk, for little gain, because this
113 		 *	simple hack works for our purpose.
114 		 */
115 		bp->b_bcount = 0;
116 		return;
117 	}
118 
119 	assert(bp->b_vp);
120 	if (!bp->b_vp->v_logical)
121 		TAILQ_REMOVE(&buftail, bp, b_tailq);
122 	free(bp->b_data);
123 	free(bp);
124 }
125 
126 static int
127 bwrite_impl(struct m_buf *bp)
128 {
129 	off_t	offset;
130 	ssize_t	rv;
131 	fsinfo_t *fs = bp->b_fs;
132 
133 	assert (bp != NULL);
134 	offset = (off_t)bp->b_blkno * fs->sectorsize + fs->offset;
135 	if (debug & DEBUG_BUF_BWRITE)
136 		printf("bwrite: blkno %lld offset %lld bcount %ld\n",
137 		    (long long)bp->b_blkno, (long long) offset,
138 		    bp->b_bcount);
139 	if (lseek(bp->b_fs->fd, offset, SEEK_SET) == -1)
140 		return (errno);
141 	rv = write(bp->b_fs->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)
146 		return (0);
147 	else if (rv == -1)		/* write error */
148 		return (errno);
149 	else				/* short write ? */
150 		return (EAGAIN);
151 }
152 
153 int
154 bwrite(struct m_buf *bp)
155 {
156 	int error = bwrite_impl(bp);
157 
158 	/*
159 	 * XXX	currently limited to HAMMER2, but this is the way bwrite
160 	 *	and its variants work, otherwise bufs may be leaked.
161 	 */
162 	if (bp->b_is_hammer2)
163 		brelse(bp);
164 
165 	return (error);
166 }
167 
168 void
169 bcleanup(void)
170 {
171 	struct m_buf *bp;
172 
173 	/*
174 	 * XXX	this really shouldn't be necessary, but i'm curious to
175 	 *	know why there's still some buffers lying around that
176 	 *	aren't brelse()d
177 	 */
178 
179 	if (TAILQ_EMPTY(&buftail)) {
180 		printf("bcleanup: clean\n");
181 		return;
182 	}
183 
184 	printf("bcleanup: unflushed buffers:\n");
185 	TAILQ_FOREACH(bp, &buftail, b_tailq) {
186 		printf("\t%p  lblkno %10lld  blkno %10lld  count %6ld  bufsize %6ld  "
187 		    "loffset %016lx  cmd %d  [vp %p  data %p  type %d  logical %d  vflushed %d]\n",
188 		    bp, (long long)bp->b_lblkno, (long long)bp->b_blkno,
189 		    bp->b_bcount, bp->b_bufsize,
190 		    bp->b_loffset, bp->b_cmd, bp->b_vp,
191 		    bp->b_vp ? bp->b_vp->v_data : NULL,
192 		    bp->b_vp ? bp->b_vp->v_type : -1,
193 		    bp->b_vp ? bp->b_vp->v_logical : -1,
194 		    bp->b_vp ? bp->b_vp->v_vflushed : -1);
195 		if (bp->b_vp)
196 			assert(!bp->b_vp->v_logical);
197 	}
198 	printf("bcleanup: done\n");
199 }
200 
201 struct m_buf *
202 getblk(struct m_vnode *vp, makefs_daddr_t blkno, int size, int u1 __unused,
203     int u2 __unused, int u3 __unused)
204 {
205 	static int buftailinitted;
206 	struct m_buf *bp;
207 	void *n;
208 
209 	bp = NULL;
210 	if (vp->v_logical)
211 		goto skip_lookup;
212 
213 	if (debug & DEBUG_BUF_GETBLK)
214 		printf("getblk: blkno %lld size %d\n", (long long)blkno, size);
215 
216 	if (!buftailinitted) {
217 		if (debug & DEBUG_BUF_GETBLK)
218 			printf("getblk: initialising tailq\n");
219 		TAILQ_INIT(&buftail);
220 		buftailinitted = 1;
221 	} else {
222 		TAILQ_FOREACH(bp, &buftail, b_tailq) {
223 			if (bp->b_lblkno != blkno)
224 				continue;
225 			break;
226 		}
227 	}
228 skip_lookup:
229 	if (bp == NULL) {
230 		bp = ecalloc(1, sizeof(*bp));
231 		bp->b_bufsize = 0;
232 		bp->b_blkno = bp->b_lblkno = blkno;
233 		bp->b_fs = vp->fs;
234 		bp->b_data = NULL;
235 		bp->b_vp = vp;
236 		assert(bp->b_vp);
237 		if (!bp->b_vp->v_logical)
238 			TAILQ_INSERT_HEAD(&buftail, bp, b_tailq);
239 	}
240 	bp->b_bcount = size;
241 	if (bp->b_data == NULL || bp->b_bcount > bp->b_bufsize) {
242 		n = erealloc(bp->b_data, size);
243 		memset(n, 0, size);
244 		bp->b_data = n;
245 		bp->b_bufsize = size;
246 	}
247 
248 	return (bp);
249 }
250