ffs_balloc.c revision 1.1.1.1 1 /*
2 * Copyright (c) 1982, 1986, 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 * @(#)ffs_balloc.c 8.4 (Berkeley) 9/23/93
34 */
35
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/buf.h>
39 #include <sys/proc.h>
40 #include <sys/file.h>
41 #include <sys/vnode.h>
42
43 #include <vm/vm.h>
44
45 #include <ufs/ufs/quota.h>
46 #include <ufs/ufs/inode.h>
47 #include <ufs/ufs/ufs_extern.h>
48
49 #include <ufs/ffs/fs.h>
50 #include <ufs/ffs/ffs_extern.h>
51
52 /*
53 * Balloc defines the structure of file system storage
54 * by allocating the physical blocks on a device given
55 * the inode and the logical block number in a file.
56 */
57 ffs_balloc(ip, bn, size, cred, bpp, flags)
58 register struct inode *ip;
59 register daddr_t bn;
60 int size;
61 struct ucred *cred;
62 struct buf **bpp;
63 int flags;
64 {
65 register struct fs *fs;
66 register daddr_t nb;
67 struct buf *bp, *nbp;
68 struct vnode *vp = ITOV(ip);
69 struct indir indirs[NIADDR + 2];
70 daddr_t newb, lbn, *bap, pref;
71 int osize, nsize, num, i, error;
72
73 *bpp = NULL;
74 if (bn < 0)
75 return (EFBIG);
76 fs = ip->i_fs;
77 lbn = bn;
78
79 /*
80 * If the next write will extend the file into a new block,
81 * and the file is currently composed of a fragment
82 * this fragment has to be extended to be a full block.
83 */
84 nb = lblkno(fs, ip->i_size);
85 if (nb < NDADDR && nb < bn) {
86 osize = blksize(fs, ip, nb);
87 if (osize < fs->fs_bsize && osize > 0) {
88 error = ffs_realloccg(ip, nb,
89 ffs_blkpref(ip, nb, (int)nb, &ip->i_db[0]),
90 osize, (int)fs->fs_bsize, cred, &bp);
91 if (error)
92 return (error);
93 ip->i_size = (nb + 1) * fs->fs_bsize;
94 vnode_pager_setsize(vp, (u_long)ip->i_size);
95 ip->i_db[nb] = dbtofsb(fs, bp->b_blkno);
96 ip->i_flag |= IN_CHANGE | IN_UPDATE;
97 if (flags & B_SYNC)
98 bwrite(bp);
99 else
100 bawrite(bp);
101 }
102 }
103 /*
104 * The first NDADDR blocks are direct blocks
105 */
106 if (bn < NDADDR) {
107 nb = ip->i_db[bn];
108 if (nb != 0 && ip->i_size >= (bn + 1) * fs->fs_bsize) {
109 error = bread(vp, bn, fs->fs_bsize, NOCRED, &bp);
110 if (error) {
111 brelse(bp);
112 return (error);
113 }
114 *bpp = bp;
115 return (0);
116 }
117 if (nb != 0) {
118 /*
119 * Consider need to reallocate a fragment.
120 */
121 osize = fragroundup(fs, blkoff(fs, ip->i_size));
122 nsize = fragroundup(fs, size);
123 if (nsize <= osize) {
124 error = bread(vp, bn, osize, NOCRED, &bp);
125 if (error) {
126 brelse(bp);
127 return (error);
128 }
129 } else {
130 error = ffs_realloccg(ip, bn,
131 ffs_blkpref(ip, bn, (int)bn, &ip->i_db[0]),
132 osize, nsize, cred, &bp);
133 if (error)
134 return (error);
135 }
136 } else {
137 if (ip->i_size < (bn + 1) * fs->fs_bsize)
138 nsize = fragroundup(fs, size);
139 else
140 nsize = fs->fs_bsize;
141 error = ffs_alloc(ip, bn,
142 ffs_blkpref(ip, bn, (int)bn, &ip->i_db[0]),
143 nsize, cred, &newb);
144 if (error)
145 return (error);
146 bp = getblk(vp, bn, nsize, 0, 0);
147 bp->b_blkno = fsbtodb(fs, newb);
148 if (flags & B_CLRBUF)
149 clrbuf(bp);
150 }
151 ip->i_db[bn] = dbtofsb(fs, bp->b_blkno);
152 ip->i_flag |= IN_CHANGE | IN_UPDATE;
153 *bpp = bp;
154 return (0);
155 }
156 /*
157 * Determine the number of levels of indirection.
158 */
159 pref = 0;
160 if (error = ufs_getlbns(vp, bn, indirs, &num))
161 return(error);
162 #ifdef DIAGNOSTIC
163 if (num < 1)
164 panic ("ffs_balloc: ufs_bmaparray returned indirect block\n");
165 #endif
166 /*
167 * Fetch the first indirect block allocating if necessary.
168 */
169 --num;
170 nb = ip->i_ib[indirs[0].in_off];
171 if (nb == 0) {
172 pref = ffs_blkpref(ip, lbn, 0, (daddr_t *)0);
173 if (error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize,
174 cred, &newb))
175 return (error);
176 nb = newb;
177 bp = getblk(vp, indirs[1].in_lbn, fs->fs_bsize, 0, 0);
178 bp->b_blkno = fsbtodb(fs, newb);
179 clrbuf(bp);
180 /*
181 * Write synchronously so that indirect blocks
182 * never point at garbage.
183 */
184 if (error = bwrite(bp)) {
185 ffs_blkfree(ip, nb, fs->fs_bsize);
186 return (error);
187 }
188 ip->i_ib[indirs[0].in_off] = newb;
189 ip->i_flag |= IN_CHANGE | IN_UPDATE;
190 }
191 /*
192 * Fetch through the indirect blocks, allocating as necessary.
193 */
194 for (i = 1;;) {
195 error = bread(vp,
196 indirs[i].in_lbn, (int)fs->fs_bsize, NOCRED, &bp);
197 if (error) {
198 brelse(bp);
199 return (error);
200 }
201 bap = (daddr_t *)bp->b_data;
202 nb = bap[indirs[i].in_off];
203 if (i == num)
204 break;
205 i += 1;
206 if (nb != 0) {
207 brelse(bp);
208 continue;
209 }
210 if (pref == 0)
211 pref = ffs_blkpref(ip, lbn, 0, (daddr_t *)0);
212 if (error =
213 ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, cred, &newb)) {
214 brelse(bp);
215 return (error);
216 }
217 nb = newb;
218 nbp = getblk(vp, indirs[i].in_lbn, fs->fs_bsize, 0, 0);
219 nbp->b_blkno = fsbtodb(fs, nb);
220 clrbuf(nbp);
221 /*
222 * Write synchronously so that indirect blocks
223 * never point at garbage.
224 */
225 if (error = bwrite(nbp)) {
226 ffs_blkfree(ip, nb, fs->fs_bsize);
227 brelse(bp);
228 return (error);
229 }
230 bap[indirs[i - 1].in_off] = nb;
231 /*
232 * If required, write synchronously, otherwise use
233 * delayed write.
234 */
235 if (flags & B_SYNC) {
236 bwrite(bp);
237 } else {
238 bdwrite(bp);
239 }
240 }
241 /*
242 * Get the data block, allocating if necessary.
243 */
244 if (nb == 0) {
245 pref = ffs_blkpref(ip, lbn, indirs[i].in_off, &bap[0]);
246 if (error = ffs_alloc(ip,
247 lbn, pref, (int)fs->fs_bsize, cred, &newb)) {
248 brelse(bp);
249 return (error);
250 }
251 nb = newb;
252 nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0);
253 nbp->b_blkno = fsbtodb(fs, nb);
254 if (flags & B_CLRBUF)
255 clrbuf(nbp);
256 bap[indirs[i].in_off] = nb;
257 /*
258 * If required, write synchronously, otherwise use
259 * delayed write.
260 */
261 if (flags & B_SYNC) {
262 bwrite(bp);
263 } else {
264 bdwrite(bp);
265 }
266 *bpp = nbp;
267 return (0);
268 }
269 brelse(bp);
270 if (flags & B_CLRBUF) {
271 error = bread(vp, lbn, (int)fs->fs_bsize, NOCRED, &nbp);
272 if (error) {
273 brelse(nbp);
274 return (error);
275 }
276 } else {
277 nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0);
278 nbp->b_blkno = fsbtodb(fs, nb);
279 }
280 *bpp = nbp;
281 return (0);
282 }
283