1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2002 Juli Mallett.  All rights reserved.
5 *
6 * This software was written by Juli Mallett <jmallett@FreeBSD.org> for the
7 * FreeBSD project.  Redistribution and use in source and binary forms, with
8 * or without modification, are permitted provided that the following
9 * conditions are met:
10 *
11 * 1. Redistribution of source code must retain the above copyright notice,
12 *    this list of conditions and the following disclaimer.
13 * 2. Redistribution in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
21 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
23 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
25 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
26 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27 * POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD$");
32
33#include <sys/param.h>
34#include <sys/mount.h>
35#include <sys/disklabel.h>
36#include <sys/stat.h>
37
38#include <ufs/ufs/ufsmount.h>
39#include <ufs/ufs/dinode.h>
40#include <ufs/ffs/fs.h>
41
42#include <errno.h>
43#include <stdio.h>
44#include <string.h>
45#include <stdlib.h>
46#include <unistd.h>
47
48#include <libufs.h>
49
50int
51sbread(struct uufsd *disk)
52{
53	struct fs *fs;
54
55	ERROR(disk, NULL);
56
57	if ((errno = sbget(disk->d_fd, &fs, -1)) != 0) {
58		switch (errno) {
59		case EIO:
60			ERROR(disk, "non-existent or truncated superblock");
61			break;
62		case ENOENT:
63			ERROR(disk, "no usable known superblock found");
64			break;
65		case ENOSPC:
66			ERROR(disk, "failed to allocate space for superblock "
67			    "information");
68			break;
69		case EINVAL:
70			ERROR(disk, "The previous newfs operation on this "
71			    "volume did not complete.\nYou must complete "
72			    "newfs before using this volume.");
73			break;
74		default:
75			ERROR(disk, "unknown superblock read error");
76			errno = EIO;
77			break;
78		}
79		disk->d_ufs = 0;
80		return (-1);
81	}
82	memcpy(&disk->d_fs, fs, fs->fs_sbsize);
83	free(fs);
84	fs = &disk->d_fs;
85	if (fs->fs_magic == FS_UFS1_MAGIC)
86		disk->d_ufs = 1;
87	if (fs->fs_magic == FS_UFS2_MAGIC)
88		disk->d_ufs = 2;
89	disk->d_bsize = fs->fs_fsize / fsbtodb(fs, 1);
90	disk->d_sblock = fs->fs_sblockloc / disk->d_bsize;
91	disk->d_sbcsum = fs->fs_csp;
92	return (0);
93}
94
95int
96sbwrite(struct uufsd *disk, int all)
97{
98	struct fs *fs;
99	int rv;
100
101	ERROR(disk, NULL);
102
103	rv = ufs_disk_write(disk);
104	if (rv == -1) {
105		ERROR(disk, "failed to open disk for writing");
106		return (-1);
107	}
108
109	fs = &disk->d_fs;
110	if ((errno = sbput(disk->d_fd, fs, all ? fs->fs_ncg : 0)) != 0) {
111		switch (errno) {
112		case EIO:
113			ERROR(disk, "failed to write superblock");
114			break;
115		default:
116			ERROR(disk, "unknown superblock write error");
117			errno = EIO;
118			break;
119		}
120		return (-1);
121	}
122	return (0);
123}
124
125/*
126 * These are the low-level functions that actually read and write
127 * the superblock and its associated data. The actual work is done by
128 * the functions ffs_sbget and ffs_sbput in /sys/ufs/ffs/ffs_subr.c.
129 */
130static int use_pread(void *devfd, off_t loc, void **bufp, int size);
131static int use_pwrite(void *devfd, off_t loc, void *buf, int size);
132
133/*
134 * Read a superblock from the devfd device allocating memory returned
135 * in fsp. Also read the superblock summary information.
136 */
137int
138sbget(int devfd, struct fs **fsp, off_t sblockloc)
139{
140
141	return (ffs_sbget(&devfd, fsp, sblockloc, "user", use_pread));
142}
143
144/*
145 * A read function for use by user-level programs using libufs.
146 */
147static int
148use_pread(void *devfd, off_t loc, void **bufp, int size)
149{
150	int fd;
151
152	fd = *(int *)devfd;
153	if ((*bufp = malloc(size)) == NULL)
154		return (ENOSPC);
155	if (pread(fd, *bufp, size, loc) != size)
156		return (EIO);
157	return (0);
158}
159
160/*
161 * Write a superblock to the devfd device from the memory pointed to by fs.
162 * Also write out the superblock summary information but do not free the
163 * summary information memory.
164 *
165 * Additionally write out numaltwrite of the alternate superblocks. Use
166 * fs->fs_ncg to write out all of the alternate superblocks.
167 */
168int
169sbput(int devfd, struct fs *fs, int numaltwrite)
170{
171	struct csum *savedcsp;
172	off_t savedactualloc;
173	int i, error;
174
175	if ((error = ffs_sbput(&devfd, fs, fs->fs_sblockactualloc,
176	     use_pwrite)) != 0)
177		return (error);
178	if (numaltwrite == 0)
179		return (0);
180	savedactualloc = fs->fs_sblockactualloc;
181	savedcsp = fs->fs_csp;
182	fs->fs_csp = NULL;
183	for (i = 0; i < numaltwrite; i++) {
184		fs->fs_sblockactualloc = dbtob(fsbtodb(fs, cgsblock(fs, i)));
185		if ((error = ffs_sbput(&devfd, fs, fs->fs_sblockactualloc,
186		     use_pwrite)) != 0) {
187			fs->fs_sblockactualloc = savedactualloc;
188			fs->fs_csp = savedcsp;
189			return (-1);
190		}
191	}
192	fs->fs_sblockactualloc = savedactualloc;
193	fs->fs_csp = savedcsp;
194	return (0);
195}
196
197/*
198 * A write function for use by user-level programs using sbput in libufs.
199 */
200static int
201use_pwrite(void *devfd, off_t loc, void *buf, int size)
202{
203	int fd;
204
205	fd = *(int *)devfd;
206	if (pwrite(fd, buf, size, loc) != size)
207		return (EIO);
208	return (0);
209}
210