xref: /freebsd/sys/ufs/ffs/ffs_balloc.c (revision a79b71281cd63ad7a6cc43a6d5673a2510b51630)
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	8.8 (Berkeley) 6/16/95
34  * $FreeBSD$
35  */
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/bio.h>
40 #include <sys/buf.h>
41 #include <sys/lock.h>
42 #include <sys/mount.h>
43 #include <sys/vnode.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 int
58 ffs_balloc(ap)
59 	struct vop_balloc_args /* {
60 		struct vnode *a_vp;
61 		ufs_daddr_t a_lbn;
62 		int a_size;
63 		struct ucred *a_cred;
64 		int a_flags;
65 		struct buf *a_bpp;
66 	} */ *ap;
67 {
68 	struct inode *ip;
69 	ufs_daddr_t lbn;
70 	int size;
71 	struct ucred *cred;
72 	int flags;
73 	struct fs *fs;
74 	ufs_daddr_t nb;
75 	struct buf *bp, *nbp;
76 	struct vnode *vp;
77 	struct indir indirs[NIADDR + 2];
78 	ufs_daddr_t newb, *bap, pref;
79 	int deallocated, osize, nsize, num, i, error;
80 	ufs_daddr_t *allocib, *blkp, *allocblk, allociblk[NIADDR + 1];
81 	int unwindidx = -1;
82 	struct proc *p = curproc;	/* XXX */
83 
84 	vp = ap->a_vp;
85 	ip = VTOI(vp);
86 	fs = ip->i_fs;
87 	lbn = lblkno(fs, ap->a_startoffset);
88 	size = blkoff(fs, ap->a_startoffset) + ap->a_size;
89 	if (size > fs->fs_bsize)
90 		panic("ffs_balloc: blk too big");
91 	*ap->a_bpp = NULL;
92 	if (lbn < 0)
93 		return (EFBIG);
94 	cred = ap->a_cred;
95 	flags = ap->a_flags;
96 
97 	/*
98 	 * If the next write will extend the file into a new block,
99 	 * and the file is currently composed of a fragment
100 	 * this fragment has to be extended to be a full block.
101 	 */
102 	nb = lblkno(fs, ip->i_size);
103 	if (nb < NDADDR && nb < lbn) {
104 		osize = blksize(fs, ip, nb);
105 		if (osize < fs->fs_bsize && osize > 0) {
106 			error = ffs_realloccg(ip, nb,
107 				ffs_blkpref(ip, nb, (int)nb, &ip->i_db[0]),
108 				osize, (int)fs->fs_bsize, cred, &bp);
109 			if (error)
110 				return (error);
111 			if (DOINGSOFTDEP(vp))
112 				softdep_setup_allocdirect(ip, nb,
113 				    dbtofsb(fs, bp->b_blkno), ip->i_db[nb],
114 				    fs->fs_bsize, osize, bp);
115 			ip->i_size = smalllblktosize(fs, nb + 1);
116 			ip->i_db[nb] = dbtofsb(fs, bp->b_blkno);
117 			ip->i_flag |= IN_CHANGE | IN_UPDATE;
118 			if (flags & B_SYNC)
119 				bwrite(bp);
120 			else
121 				bawrite(bp);
122 		}
123 	}
124 	/*
125 	 * The first NDADDR blocks are direct blocks
126 	 */
127 	if (lbn < NDADDR) {
128 		nb = ip->i_db[lbn];
129 		if (nb != 0 && ip->i_size >= smalllblktosize(fs, lbn + 1)) {
130 			error = bread(vp, lbn, fs->fs_bsize, NOCRED, &bp);
131 			if (error) {
132 				brelse(bp);
133 				return (error);
134 			}
135 			bp->b_blkno = fsbtodb(fs, nb);
136 			*ap->a_bpp = bp;
137 			return (0);
138 		}
139 		if (nb != 0) {
140 			/*
141 			 * Consider need to reallocate a fragment.
142 			 */
143 			osize = fragroundup(fs, blkoff(fs, ip->i_size));
144 			nsize = fragroundup(fs, size);
145 			if (nsize <= osize) {
146 				error = bread(vp, lbn, osize, NOCRED, &bp);
147 				if (error) {
148 					brelse(bp);
149 					return (error);
150 				}
151 				bp->b_blkno = fsbtodb(fs, nb);
152 			} else {
153 				error = ffs_realloccg(ip, lbn,
154 				    ffs_blkpref(ip, lbn, (int)lbn,
155 					&ip->i_db[0]), osize, nsize, cred, &bp);
156 				if (error)
157 					return (error);
158 				if (DOINGSOFTDEP(vp))
159 					softdep_setup_allocdirect(ip, lbn,
160 					    dbtofsb(fs, bp->b_blkno), nb,
161 					    nsize, osize, bp);
162 			}
163 		} else {
164 			if (ip->i_size < smalllblktosize(fs, lbn + 1))
165 				nsize = fragroundup(fs, size);
166 			else
167 				nsize = fs->fs_bsize;
168 			error = ffs_alloc(ip, lbn,
169 			    ffs_blkpref(ip, lbn, (int)lbn, &ip->i_db[0]),
170 			    nsize, cred, &newb);
171 			if (error)
172 				return (error);
173 			bp = getblk(vp, lbn, nsize, 0, 0);
174 			bp->b_blkno = fsbtodb(fs, newb);
175 			if (flags & B_CLRBUF)
176 				vfs_bio_clrbuf(bp);
177 			if (DOINGSOFTDEP(vp))
178 				softdep_setup_allocdirect(ip, lbn, newb, 0,
179 				    nsize, 0, bp);
180 		}
181 		ip->i_db[lbn] = dbtofsb(fs, bp->b_blkno);
182 		ip->i_flag |= IN_CHANGE | IN_UPDATE;
183 		*ap->a_bpp = bp;
184 		return (0);
185 	}
186 	/*
187 	 * Determine the number of levels of indirection.
188 	 */
189 	pref = 0;
190 	if ((error = ufs_getlbns(vp, lbn, indirs, &num)) != 0)
191 		return(error);
192 #ifdef DIAGNOSTIC
193 	if (num < 1)
194 		panic ("ffs_balloc: ufs_bmaparray returned indirect block");
195 #endif
196 	/*
197 	 * Fetch the first indirect block allocating if necessary.
198 	 */
199 	--num;
200 	nb = ip->i_ib[indirs[0].in_off];
201 	allocib = NULL;
202 	allocblk = allociblk;
203 	if (nb == 0) {
204 		pref = ffs_blkpref(ip, lbn, 0, (ufs_daddr_t *)0);
205 	        if ((error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize,
206 		    cred, &newb)) != 0)
207 			return (error);
208 		nb = newb;
209 		*allocblk++ = nb;
210 		bp = getblk(vp, indirs[1].in_lbn, fs->fs_bsize, 0, 0);
211 		bp->b_blkno = fsbtodb(fs, nb);
212 		vfs_bio_clrbuf(bp);
213 		if (DOINGSOFTDEP(vp)) {
214 			softdep_setup_allocdirect(ip, NDADDR + indirs[0].in_off,
215 			    newb, 0, fs->fs_bsize, 0, bp);
216 			bdwrite(bp);
217 		} else {
218 			/*
219 			 * Write synchronously so that indirect blocks
220 			 * never point at garbage.
221 			 */
222 			if (DOINGASYNC(vp))
223 				bdwrite(bp);
224 			else if ((error = bwrite(bp)) != 0)
225 				goto fail;
226 		}
227 		allocib = &ip->i_ib[indirs[0].in_off];
228 		*allocib = nb;
229 		ip->i_flag |= IN_CHANGE | IN_UPDATE;
230 	}
231 	/*
232 	 * Fetch through the indirect blocks, allocating as necessary.
233 	 */
234 	for (i = 1;;) {
235 		error = bread(vp,
236 		    indirs[i].in_lbn, (int)fs->fs_bsize, NOCRED, &bp);
237 		if (error) {
238 			brelse(bp);
239 			goto fail;
240 		}
241 		bap = (ufs_daddr_t *)bp->b_data;
242 		nb = bap[indirs[i].in_off];
243 		if (i == num)
244 			break;
245 		i += 1;
246 		if (nb != 0) {
247 			bqrelse(bp);
248 			continue;
249 		}
250 		if (pref == 0)
251 			pref = ffs_blkpref(ip, lbn, 0, (ufs_daddr_t *)0);
252 		if ((error =
253 		    ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, cred, &newb)) != 0) {
254 			brelse(bp);
255 			goto fail;
256 		}
257 		nb = newb;
258 		*allocblk++ = nb;
259 		nbp = getblk(vp, indirs[i].in_lbn, fs->fs_bsize, 0, 0);
260 		nbp->b_blkno = fsbtodb(fs, nb);
261 		vfs_bio_clrbuf(nbp);
262 		if (DOINGSOFTDEP(vp)) {
263 			softdep_setup_allocindir_meta(nbp, ip, bp,
264 			    indirs[i - 1].in_off, nb);
265 			bdwrite(nbp);
266 		} else {
267 			/*
268 			 * Write synchronously so that indirect blocks
269 			 * never point at garbage.
270 			 */
271 			if ((error = bwrite(nbp)) != 0) {
272 				brelse(bp);
273 				goto fail;
274 			}
275 		}
276 		bap[indirs[i - 1].in_off] = nb;
277 		if (allocib == NULL && unwindidx < 0)
278 			unwindidx = i - 1;
279 		/*
280 		 * If required, write synchronously, otherwise use
281 		 * delayed write.
282 		 */
283 		if (flags & B_SYNC) {
284 			bwrite(bp);
285 		} else {
286 			if (bp->b_bufsize == fs->fs_bsize)
287 				bp->b_flags |= B_CLUSTEROK;
288 			bdwrite(bp);
289 		}
290 	}
291 	/*
292 	 * Get the data block, allocating if necessary.
293 	 */
294 	if (nb == 0) {
295 		pref = ffs_blkpref(ip, lbn, indirs[i].in_off, &bap[0]);
296 		error = ffs_alloc(ip,
297 		    lbn, pref, (int)fs->fs_bsize, cred, &newb);
298 		if (error) {
299 			brelse(bp);
300 			goto fail;
301 		}
302 		nb = newb;
303 		*allocblk++ = nb;
304 		nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0);
305 		nbp->b_blkno = fsbtodb(fs, nb);
306 		if (flags & B_CLRBUF)
307 			vfs_bio_clrbuf(nbp);
308 		if (DOINGSOFTDEP(vp))
309 			softdep_setup_allocindir_page(ip, lbn, bp,
310 			    indirs[i].in_off, nb, 0, nbp);
311 		bap[indirs[i].in_off] = nb;
312 		/*
313 		 * If required, write synchronously, otherwise use
314 		 * delayed write.
315 		 */
316 		if (flags & B_SYNC) {
317 			bwrite(bp);
318 		} else {
319 			if (bp->b_bufsize == fs->fs_bsize)
320 				bp->b_flags |= B_CLUSTEROK;
321 			bdwrite(bp);
322 		}
323 		*ap->a_bpp = nbp;
324 		return (0);
325 	}
326 	brelse(bp);
327 	if (flags & B_CLRBUF) {
328 		error = bread(vp, lbn, (int)fs->fs_bsize, NOCRED, &nbp);
329 		if (error) {
330 			brelse(nbp);
331 			goto fail;
332 		}
333 	} else {
334 		nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0);
335 		nbp->b_blkno = fsbtodb(fs, nb);
336 	}
337 	*ap->a_bpp = nbp;
338 	return (0);
339 fail:
340 	/*
341 	 * If we have failed part way through block allocation, we
342 	 * have to deallocate any indirect blocks that we have allocated.
343 	 * We have to fsync the file before we start to get rid of all
344 	 * of its dependencies so that we do not leave them dangling.
345 	 * We have to sync it at the end so that the soft updates code
346 	 * does not find any untracked changes. Although this is really
347 	 * slow, running out of disk space is not expected to be a common
348 	 * occurence. The error return from fsync is ignored as we already
349 	 * have an error to return to the user.
350 	 */
351 	(void) VOP_FSYNC(vp, cred, MNT_WAIT, p);
352 	for (deallocated = 0, blkp = allociblk; blkp < allocblk; blkp++) {
353 		ffs_blkfree(ip, *blkp, fs->fs_bsize);
354 		deallocated += fs->fs_bsize;
355 	}
356 	if (allocib != NULL) {
357 		*allocib = 0;
358 	} else if (unwindidx >= 0) {
359 		int r;
360 
361 		r = bread(vp, indirs[unwindidx].in_lbn,
362 		    (int)fs->fs_bsize, NOCRED, &bp);
363 		if (r) {
364 			panic("Could not unwind indirect block, error %d", r);
365 			brelse(bp);
366 		} else {
367 			bap = (ufs_daddr_t *)bp->b_data;
368 			bap[indirs[unwindidx].in_off] = 0;
369 			if (flags & B_SYNC) {
370 				bwrite(bp);
371 			} else {
372 				if (bp->b_bufsize == fs->fs_bsize)
373 					bp->b_flags |= B_CLUSTEROK;
374 				bdwrite(bp);
375 			}
376 		}
377 	}
378 	if (deallocated) {
379 #ifdef QUOTA
380 		/*
381 		 * Restore user's disk quota because allocation failed.
382 		 */
383 		(void) chkdq(ip, (long)-btodb(deallocated), cred, FORCE);
384 #endif
385 		ip->i_blocks -= btodb(deallocated);
386 		ip->i_flag |= IN_CHANGE | IN_UPDATE;
387 	}
388 	(void) VOP_FSYNC(vp, cred, MNT_WAIT, p);
389 	return (error);
390 }
391