xref: /netbsd-src/sys/fs/v7fs/v7fs_superblock.c (revision 1b9578b8c2c1f848eeb16dabbfd7d1f0d9fdefbd)
1 /*	$NetBSD: v7fs_superblock.c,v 1.1 2011/06/27 11:52:25 uch Exp $	*/
2 
3 /*-
4  * Copyright (c) 2011 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by UCHIYAMA Yasushi.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: v7fs_superblock.c,v 1.1 2011/06/27 11:52:25 uch Exp $");
34 #if defined _KERNEL_OPT
35 #include "opt_v7fs.h"
36 #endif
37 
38 #ifdef _KERNEL
39 #include <sys/systm.h>
40 #include <sys/param.h>	/* errno */
41 #else
42 #include <stdio.h>
43 #include <string.h>
44 #include <errno.h>
45 #endif
46 
47 #include "v7fs.h"
48 #include "v7fs_impl.h"
49 #include "v7fs_endian.h"
50 #include "v7fs_superblock.h"
51 #include "v7fs_inode.h"
52 #include "v7fs_datablock.h"
53 
54 #ifdef V7FS_SUPERBLOCK_DEBUG
55 #define	DPRINTF(fmt, args...)	printf("%s: " fmt, __func__, ##args)
56 #define	DPRINTF_(fmt, args...)	printf(fmt, ##args)
57 #else
58 #define	DPRINTF(fmt, args...)	((void)0)
59 #define	DPRINTF_(fmt, args...)	((void)0)
60 #endif
61 
62 static void v7fs_superblock_endian_convert(struct v7fs_self *,
63     struct v7fs_superblock *, struct v7fs_superblock *);
64 static int v7fs_superblock_sanity(struct v7fs_self *);
65 
66 /* Load superblock from disk. */
67 int
68 v7fs_superblock_load(struct v7fs_self *fs)
69 {
70 	struct v7fs_superblock *disksb;
71 	void *buf;
72 	int error;
73 
74 	if (!(buf = scratch_read(fs, V7FS_SUPERBLOCK_SECTOR)))
75 		return EIO;
76 	disksb = (struct v7fs_superblock *)buf;
77 	v7fs_superblock_endian_convert(fs, &fs->superblock, disksb);
78 	scratch_free(fs, buf);
79 
80 	if ((error = v7fs_superblock_sanity(fs)))
81 		return error;
82 
83 	return 0;
84 }
85 
86 /* Writeback superblock to disk. */
87 int
88 v7fs_superblock_writeback(struct v7fs_self *fs)
89 {
90 	struct v7fs_superblock *memsb = &fs->superblock;
91 	struct v7fs_superblock *disksb;
92 	void *buf;
93 	int error = 0;
94 
95 	if (!memsb->modified)
96 		return 0;
97 
98 	if (!(buf = scratch_read(fs, V7FS_SUPERBLOCK_SECTOR)))
99 		return EIO;
100 	disksb = (struct v7fs_superblock *)buf;
101 	v7fs_superblock_endian_convert(fs, disksb, memsb);
102 	if (!fs->io.write(fs->io.cookie, buf, V7FS_SUPERBLOCK_SECTOR))
103 		error = EIO;
104 	scratch_free(fs, buf);
105 
106 	memsb->modified = 0;
107 	DPRINTF("done. %d\n", error);
108 
109 	return error;
110 }
111 
112 /* Check endian mismatch. */
113 static int
114 v7fs_superblock_sanity(struct v7fs_self *fs)
115 {
116 	const struct v7fs_superblock *sb = &fs->superblock;
117 	void *buf = 0;
118 
119 	if ((sb->volume_size < 128) || /* smaller than 64KB. */
120 	    (sb->datablock_start_sector > sb->volume_size) ||
121 	    (sb->nfreeinode > V7FS_MAX_FREEINODE) ||
122 	    (sb->nfreeblock > V7FS_MAX_FREEBLOCK) ||
123 	    (sb->update_time < 0) ||
124 	    (sb->total_freeblock > sb->volume_size) ||
125 	    ((sb->nfreeinode == 0) && (sb->nfreeblock == 0) &&
126 		(sb->total_freeblock == 0) && (sb->total_freeinode == 0)) ||
127 	    (!(buf = scratch_read(fs, sb->volume_size - 1)))) {
128 		DPRINTF("invalid super block.\n");
129 		return EINVAL;
130 	}
131 	if (buf)
132 		scratch_free(fs, buf);
133 
134 	return 0;
135 }
136 
137 /* Fill free block to superblock cache. */
138 int
139 v7fs_freeblock_update(struct v7fs_self *fs, v7fs_daddr_t blk)
140 {
141 	/* Assume superblock is locked by caller. */
142 	struct v7fs_superblock *sb = &fs->superblock;
143 	struct v7fs_freeblock *fb;
144 	void *buf;
145 	int error;
146 
147 	/* Read next freeblock table from disk. */
148 	if (!datablock_number_sanity(fs, blk) || !(buf = scratch_read(fs, blk)))
149 		return EIO;
150 
151 	/* Update in-core superblock freelist. */
152 	fb = (struct v7fs_freeblock *)buf;
153 	if ((error = v7fs_freeblock_endian_convert(fs, fb))) {
154 		scratch_free(fs, buf);
155 		return error;
156 	}
157 	DPRINTF("freeblock table#%d, nfree=%d\n", blk, fb->nfreeblock);
158 
159 	memcpy(sb->freeblock, fb->freeblock, sizeof(blk) * fb->nfreeblock);
160 	sb->nfreeblock = fb->nfreeblock;
161 	sb->modified = true;
162 	scratch_free(fs, buf);
163 
164 	return 0;
165 }
166 
167 int
168 v7fs_freeblock_endian_convert(struct v7fs_self *fs __unused,
169     struct v7fs_freeblock *fb __unused)
170 {
171 #ifdef V7FS_EI
172 	int i;
173 	int16_t nfree;
174 
175 	nfree = V7FS_VAL16(fs, fb->nfreeblock);
176 	if (nfree <= 0 || nfree > V7FS_MAX_FREEBLOCK) {
177 		DPRINTF("invalid freeblock list. %d (max=%d)\n", nfree,
178 		    V7FS_MAX_FREEBLOCK);
179 		return ENOSPC;
180 	}
181 	fb->nfreeblock = nfree;
182 
183 	for (i = 0; i < nfree; i++) {
184 		fb->freeblock[i] = V7FS_VAL32(fs, fb->freeblock[i]);
185 	}
186 #endif /* V7FS_EI */
187 
188 	return 0;
189 }
190 
191 /* Fill free inode to superblock cache. */
192 int
193 v7fs_freeinode_update(struct v7fs_self *fs)
194 {
195 	/* Assume superblock is locked by caller. */
196 	struct v7fs_superblock *sb = &fs->superblock;
197 	v7fs_ino_t *freeinode = sb->freeinode;
198 	size_t i, j, k;
199 	v7fs_ino_t ino;
200 
201 	/* Loop over all inode list. */
202 	for (i = V7FS_ILIST_SECTOR, ino = 1/* inode start from 1*/, k = 0;
203 	    i < sb->datablock_start_sector; i++) {
204 		struct v7fs_inode_diskimage *di;
205 		void *buf;
206 		if (!(buf = scratch_read(fs, i))) {
207 			DPRINTF("block %zu I/O error.\n", i);
208 			ino += V7FS_INODE_PER_BLOCK;
209 			continue;
210 		}
211 		di = (struct v7fs_inode_diskimage *)buf;
212 
213 		for (j = 0;
214 		    (j < V7FS_INODE_PER_BLOCK) && (k < V7FS_MAX_FREEINODE);
215 		    j++, di++, ino++) {
216 			if (v7fs_inode_allocated(di))
217 				continue;
218 			DPRINTF("free inode%d\n", ino);
219 			freeinode[k++] = ino;
220 		}
221 		scratch_free(fs, buf);
222 	}
223 	sb->nfreeinode = k;
224 
225 	return 0;
226 }
227 
228 static void
229 v7fs_superblock_endian_convert(struct v7fs_self *fs __unused,
230     struct v7fs_superblock *to,  struct v7fs_superblock *from)
231 {
232 #ifdef V7FS_EI
233 #define	conv16(m)	(to->m = V7FS_VAL16(fs, from->m))
234 #define	conv32(m)	(to->m = V7FS_VAL32(fs, from->m))
235 	int i;
236 
237 	conv16(datablock_start_sector);
238 	conv32(volume_size);
239 	conv16(nfreeblock);
240 	v7fs_daddr_t *dfrom = from->freeblock;
241 	v7fs_daddr_t *dto = to->freeblock;
242 	for (i = 0; i < V7FS_MAX_FREEBLOCK; i++, dfrom++, dto++)
243 		*dto = V7FS_VAL32(fs, *dfrom);
244 
245 	conv16(nfreeinode);
246 	v7fs_ino_t *ifrom = from->freeinode;
247 	v7fs_ino_t *ito = to->freeinode;
248 	for (i = 0; i < V7FS_MAX_FREEINODE; i++, ifrom++, ito++)
249 		*ito = V7FS_VAL16(fs, *ifrom);
250 
251 	conv32(update_time);
252 	conv32(total_freeblock);
253 	conv16(total_freeinode);
254 #undef conv16
255 #undef conv32
256 #else /* V7FS_EI */
257 	memcpy(to, from , sizeof(*to));
258 #endif /* V7FS_EI */
259 }
260