1 /*-
2 * modified for Lites 1.1
3 *
4 * Aug 1995, Godmar Back (gback@cs.utah.edu)
5 * University of Utah, Department of Computer Science
6 */
7 /*-
8 * SPDX-License-Identifier: BSD-3-Clause
9 *
10 * Copyright (c) 1982, 1986, 1989, 1993
11 * The Regents of the University of California. All rights reserved.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 */
37
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/endian.h>
41 #include <sys/bio.h>
42 #include <sys/buf.h>
43 #include <sys/limits.h>
44 #include <sys/lock.h>
45 #include <sys/mount.h>
46 #include <sys/vnode.h>
47
48 #include <fs/ext2fs/fs.h>
49 #include <fs/ext2fs/inode.h>
50 #include <fs/ext2fs/ext2fs.h>
51 #include <fs/ext2fs/ext2_dinode.h>
52 #include <fs/ext2fs/ext2_extern.h>
53 #include <fs/ext2fs/ext2_mount.h>
54
55 static int
ext2_ext_balloc(struct inode * ip,uint32_t lbn,int size,struct ucred * cred,struct buf ** bpp,int flags)56 ext2_ext_balloc(struct inode *ip, uint32_t lbn, int size,
57 struct ucred *cred, struct buf **bpp, int flags)
58 {
59 struct m_ext2fs *fs;
60 struct buf *bp = NULL;
61 struct vnode *vp = ITOV(ip);
62 daddr_t newblk;
63 int blks, error, allocated;
64
65 fs = ip->i_e2fs;
66 blks = howmany(size, fs->e2fs_bsize);
67
68 error = ext4_ext_get_blocks(ip, lbn, blks, cred, NULL, &allocated, &newblk);
69 if (error)
70 return (error);
71
72 if (allocated) {
73 bp = getblk(vp, lbn, fs->e2fs_bsize, 0, 0, 0);
74 if(!bp)
75 return (EIO);
76 } else {
77 error = bread(vp, lbn, fs->e2fs_bsize, NOCRED, &bp);
78 if (error) {
79 return (error);
80 }
81 }
82
83 bp->b_blkno = fsbtodb(fs, newblk);
84 if (flags & BA_CLRBUF)
85 vfs_bio_clrbuf(bp);
86
87 *bpp = bp;
88
89 return (error);
90 }
91
92 /*
93 * Balloc defines the structure of filesystem storage
94 * by allocating the physical blocks on a device given
95 * the inode and the logical block number in a file.
96 */
97 int
ext2_balloc(struct inode * ip,e2fs_lbn_t lbn,int size,struct ucred * cred,struct buf ** bpp,int flags)98 ext2_balloc(struct inode *ip, e2fs_lbn_t lbn, int size, struct ucred *cred,
99 struct buf **bpp, int flags)
100 {
101 struct m_ext2fs *fs;
102 struct ext2mount *ump;
103 struct buf *bp, *nbp;
104 struct vnode *vp = ITOV(ip);
105 struct indir indirs[EXT2_NIADDR + 2];
106 e4fs_daddr_t nb, newb;
107 e2fs_daddr_t *bap, pref;
108 int num, i, error;
109
110 *bpp = NULL;
111 if (lbn < 0)
112 return (EFBIG);
113 fs = ip->i_e2fs;
114 ump = ip->i_ump;
115
116 /*
117 * check if this is a sequential block allocation.
118 * If so, increment next_alloc fields to allow ext2_blkpref
119 * to make a good guess
120 */
121 if (lbn == ip->i_next_alloc_block + 1) {
122 ip->i_next_alloc_block++;
123 ip->i_next_alloc_goal++;
124 }
125
126 if (ip->i_flag & IN_E4EXTENTS)
127 return (ext2_ext_balloc(ip, lbn, size, cred, bpp, flags));
128
129 /*
130 * The first EXT2_NDADDR blocks are direct blocks
131 */
132 if (lbn < EXT2_NDADDR) {
133 nb = ip->i_db[lbn];
134 /*
135 * no new block is to be allocated, and no need to expand
136 * the file
137 */
138 if (nb != 0) {
139 error = bread(vp, lbn, fs->e2fs_bsize, NOCRED, &bp);
140 if (error) {
141 return (error);
142 }
143 bp->b_blkno = fsbtodb(fs, nb);
144 if (ip->i_size >= (lbn + 1) * fs->e2fs_bsize) {
145 *bpp = bp;
146 return (0);
147 }
148 } else {
149 EXT2_LOCK(ump);
150 error = ext2_alloc(ip, lbn,
151 ext2_blkpref(ip, lbn, (int)lbn, &ip->i_db[0], 0),
152 fs->e2fs_bsize, cred, &newb);
153 if (error)
154 return (error);
155 /*
156 * If the newly allocated block exceeds 32-bit limit,
157 * we can not use it in file block maps.
158 */
159 if (newb > UINT_MAX)
160 return (EFBIG);
161 bp = getblk(vp, lbn, fs->e2fs_bsize, 0, 0, 0);
162 bp->b_blkno = fsbtodb(fs, newb);
163 if (flags & BA_CLRBUF)
164 vfs_bio_clrbuf(bp);
165 }
166 ip->i_db[lbn] = dbtofsb(fs, bp->b_blkno);
167 ip->i_flag |= IN_CHANGE | IN_UPDATE;
168 *bpp = bp;
169 return (0);
170 }
171 /*
172 * Determine the number of levels of indirection.
173 */
174 pref = 0;
175 if ((error = ext2_getlbns(vp, lbn, indirs, &num)) != 0)
176 return (error);
177 #ifdef INVARIANTS
178 if (num < 1)
179 panic("ext2_balloc: ext2_getlbns returned indirect block");
180 #endif
181 /*
182 * Fetch the first indirect block allocating if necessary.
183 */
184 --num;
185 nb = ip->i_ib[indirs[0].in_off];
186 if (nb == 0) {
187 EXT2_LOCK(ump);
188 pref = ext2_blkpref(ip, lbn, indirs[0].in_off +
189 EXT2_NDIR_BLOCKS, &ip->i_db[0], 0);
190 if ((error = ext2_alloc(ip, lbn, pref, fs->e2fs_bsize, cred,
191 &newb)))
192 return (error);
193 if (newb > UINT_MAX)
194 return (EFBIG);
195 nb = newb;
196 bp = getblk(vp, indirs[1].in_lbn, fs->e2fs_bsize, 0, 0, 0);
197 bp->b_blkno = fsbtodb(fs, newb);
198 vfs_bio_clrbuf(bp);
199 /*
200 * Write synchronously so that indirect blocks
201 * never point at garbage.
202 */
203 if ((error = bwrite(bp)) != 0) {
204 ext2_blkfree(ip, nb, fs->e2fs_bsize);
205 return (error);
206 }
207 ip->i_ib[indirs[0].in_off] = newb;
208 ip->i_flag |= IN_CHANGE | IN_UPDATE;
209 }
210 /*
211 * Fetch through the indirect blocks, allocating as necessary.
212 */
213 for (i = 1;;) {
214 error = bread(vp,
215 indirs[i].in_lbn, (int)fs->e2fs_bsize, NOCRED, &bp);
216 if (error) {
217 return (error);
218 }
219 bap = (e2fs_daddr_t *)bp->b_data;
220 nb = le32toh(bap[indirs[i].in_off]);
221 if (i == num)
222 break;
223 i += 1;
224 if (nb != 0) {
225 bqrelse(bp);
226 continue;
227 }
228 EXT2_LOCK(ump);
229 if (pref == 0)
230 pref = ext2_blkpref(ip, lbn, indirs[i].in_off, bap,
231 bp->b_lblkno);
232 error = ext2_alloc(ip, lbn, pref, (int)fs->e2fs_bsize, cred, &newb);
233 if (error) {
234 brelse(bp);
235 return (error);
236 }
237 if (newb > UINT_MAX)
238 return (EFBIG);
239 nb = newb;
240 nbp = getblk(vp, indirs[i].in_lbn, fs->e2fs_bsize, 0, 0, 0);
241 nbp->b_blkno = fsbtodb(fs, nb);
242 vfs_bio_clrbuf(nbp);
243 /*
244 * Write synchronously so that indirect blocks
245 * never point at garbage.
246 */
247 if ((error = bwrite(nbp)) != 0) {
248 ext2_blkfree(ip, nb, fs->e2fs_bsize);
249 brelse(bp);
250 return (error);
251 }
252 bap[indirs[i - 1].in_off] = htole32(nb);
253 /*
254 * If required, write synchronously, otherwise use
255 * delayed write.
256 */
257 if (flags & IO_SYNC) {
258 bwrite(bp);
259 } else {
260 if (bp->b_bufsize == fs->e2fs_bsize)
261 bp->b_flags |= B_CLUSTEROK;
262 bdwrite(bp);
263 }
264 }
265 /*
266 * Get the data block, allocating if necessary.
267 */
268 if (nb == 0) {
269 EXT2_LOCK(ump);
270 pref = ext2_blkpref(ip, lbn, indirs[i].in_off, &bap[0],
271 bp->b_lblkno);
272 if ((error = ext2_alloc(ip,
273 lbn, pref, (int)fs->e2fs_bsize, cred, &newb)) != 0) {
274 brelse(bp);
275 return (error);
276 }
277 if (newb > UINT_MAX)
278 return (EFBIG);
279 nb = newb;
280 nbp = getblk(vp, lbn, fs->e2fs_bsize, 0, 0, 0);
281 nbp->b_blkno = fsbtodb(fs, nb);
282 if (flags & BA_CLRBUF)
283 vfs_bio_clrbuf(nbp);
284 bap[indirs[i].in_off] = htole32(nb);
285 /*
286 * If required, write synchronously, otherwise use
287 * delayed write.
288 */
289 if (flags & IO_SYNC) {
290 bwrite(bp);
291 } else {
292 if (bp->b_bufsize == fs->e2fs_bsize)
293 bp->b_flags |= B_CLUSTEROK;
294 bdwrite(bp);
295 }
296 *bpp = nbp;
297 return (0);
298 }
299 brelse(bp);
300 if (flags & BA_CLRBUF) {
301 int seqcount = (flags & BA_SEQMASK) >> BA_SEQSHIFT;
302
303 if (seqcount && (vp->v_mount->mnt_flag & MNT_NOCLUSTERR) == 0) {
304 error = cluster_read(vp, ip->i_size, lbn,
305 (int)fs->e2fs_bsize, NOCRED,
306 MAXBSIZE, seqcount, 0, &nbp);
307 } else {
308 error = bread(vp, lbn, (int)fs->e2fs_bsize, NOCRED, &nbp);
309 }
310 if (error) {
311 brelse(nbp);
312 return (error);
313 }
314 } else {
315 nbp = getblk(vp, lbn, fs->e2fs_bsize, 0, 0, 0);
316 nbp->b_blkno = fsbtodb(fs, nb);
317 }
318 *bpp = nbp;
319 return (0);
320 }
321