block.c revision 174668 
1/*
2 * Copyright (c) 2002 Juli Mallett.  All rights reserved.
3 *
4 * This software was written by Juli Mallett <jmallett@FreeBSD.org> for the
5 * FreeBSD project.  Redistribution and use in source and binary forms, with
6 * or without modification, are permitted provided that the following
7 * conditions are met:
8 *
9 * 1. Redistribution of source code must retain the above copyright notice,
10 *    this list of conditions and the following disclaimer.
11 * 2. Redistribution in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
19 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
20 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
23 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
24 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25 * POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD: head/lib/libufs/block.c 174668 2007-12-16 18:02:37Z phk $");
30
31#include <sys/param.h>
32#include <sys/mount.h>
33#include <sys/disk.h>
34#include <sys/disklabel.h>
35#include <sys/stat.h>
36
37#include <ufs/ufs/ufsmount.h>
38#include <ufs/ufs/dinode.h>
39#include <ufs/ffs/fs.h>
40
41#include <errno.h>
42#include <fcntl.h>
43#include <stdio.h>
44#include <stdlib.h>
45#include <string.h>
46#include <unistd.h>
47
48#include <libufs.h>
49
50ssize_t
51bread(struct uufsd *disk, ufs2_daddr_t blockno, void *data, size_t size)
52{
53	void *p2;
54	ssize_t cnt;
55
56	ERROR(disk, NULL);
57
58	p2 = data;
59	/*
60	 * XXX: various disk controllers require alignment of our buffer
61	 * XXX: which is stricter than struct alignment.
62	 * XXX: Bounce the buffer if not 64 byte aligned.
63	 * XXX: this can be removed if/when the kernel is fixed
64	 */
65	if (((intptr_t)data) & 0x3f) {
66		p2 = malloc(size);
67		if (p2 == NULL)
68			ERROR(disk, "allocate bounce buffer");
69	}
70	cnt = pread(disk->d_fd, p2, size, (off_t)(blockno * disk->d_bsize));
71	if (cnt == -1) {
72		ERROR(disk, "read error from block device");
73		goto fail;
74	}
75	if (cnt == 0) {
76		ERROR(disk, "end of file from block device");
77		goto fail;
78	}
79	if ((size_t)cnt != size) {
80		ERROR(disk, "short read or read error from block device");
81		goto fail;
82	}
83	if (p2 != data) {
84		memcpy(data, p2, size);
85		free(p2);
86	}
87	return (cnt);
88fail:	memset(data, 0, size);
89	if (p2 != data) {
90		free(p2);
91	}
92	return (-1);
93}
94
95ssize_t
96bwrite(struct uufsd *disk, ufs2_daddr_t blockno, const void *data, size_t size)
97{
98	ssize_t cnt;
99	int rv;
100	void *p2 = NULL;
101
102	ERROR(disk, NULL);
103
104	rv = ufs_disk_write(disk);
105	if (rv == -1) {
106		ERROR(disk, "failed to open disk for writing");
107		return (-1);
108	}
109
110	/*
111	 * XXX: various disk controllers require alignment of our buffer
112	 * XXX: which is stricter than struct alignment.
113	 * XXX: Bounce the buffer if not 64 byte aligned.
114	 * XXX: this can be removed if/when the kernel is fixed
115	 */
116	if (((intptr_t)data) & 0x3f) {
117		p2 = malloc(size);
118		if (p2 == NULL)
119			ERROR(disk, "allocate bounce buffer");
120		memcpy(p2, data, size);
121		data = p2;
122	}
123	cnt = pwrite(disk->d_fd, data, size, (off_t)(blockno * disk->d_bsize));
124	if (p2 != NULL)
125		free(p2);
126	if (cnt == -1) {
127		ERROR(disk, "write error to block device");
128		return (-1);
129	}
130	if ((size_t)cnt != size) {
131		ERROR(disk, "short write to block device");
132		return (-1);
133	}
134
135	return (cnt);
136}
137
138int
139berase(struct uufsd *disk, ufs2_daddr_t blockno, ufs2_daddr_t size)
140{
141	off_t ioarg[2];
142	int rv;
143
144	ERROR(disk, NULL);
145	rv = ufs_disk_write(disk);
146	if (rv == -1) {
147		ERROR(disk, "failed to open disk for writing");
148		return(rv);
149	}
150	ioarg[0] = blockno * disk->d_bsize;
151	ioarg[1] = size;
152	rv = ioctl(disk->d_fd, DIOCGDELETE, ioarg);
153	return (rv);
154}
155