xref: /dragonfly/sys/vfs/ufs/ffs_balloc.c (revision 86fe9e07)
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: src/sys/ufs/ffs/ffs_balloc.c,v 1.26.2.1 2002/10/10 19:48:20 dillon Exp $
35  * $DragonFly: src/sys/vfs/ufs/ffs_balloc.c,v 1.8 2004/07/18 19:43:48 drhodus Exp $
36  */
37 
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/proc.h>
41 #include <sys/buf.h>
42 #include <sys/lock.h>
43 #include <sys/mount.h>
44 #include <sys/vnode.h>
45 
46 #include "quota.h"
47 #include "inode.h"
48 #include "ufs_extern.h"
49 
50 #include "fs.h"
51 #include "ffs_extern.h"
52 
53 /*
54  * Balloc defines the structure of filesystem storage
55  * by allocating the physical blocks on a device given
56  * the inode and the logical block number in a file.
57  *
58  * ffs_balloc(struct vnode *a_vp, ufs_daddr_t a_lbn, int a_size,
59  *	      struct ucred *a_cred, int a_flags, struct buf *a_bpp)
60  */
61 int
62 ffs_balloc(struct vop_balloc_args *ap)
63 {
64 	struct inode *ip;
65 	ufs_daddr_t lbn;
66 	int size;
67 	struct ucred *cred;
68 	int flags;
69 	struct fs *fs;
70 	ufs_daddr_t nb;
71 	struct buf *bp, *nbp;
72 	struct vnode *vp;
73 	struct indir indirs[NIADDR + 2];
74 	ufs_daddr_t newb, *bap, pref;
75 	int deallocated, osize, nsize, num, i, error;
76 	ufs_daddr_t *allocib, *blkp, *allocblk, allociblk[NIADDR + 1];
77 	int unwindidx = -1;
78 	struct thread *td = curthread;	/* XXX */
79 
80 	vp = ap->a_vp;
81 	ip = VTOI(vp);
82 	fs = ip->i_fs;
83 	lbn = lblkno(fs, ap->a_startoffset);
84 	size = blkoff(fs, ap->a_startoffset) + ap->a_size;
85 	if (size > fs->fs_bsize)
86 		panic("ffs_balloc: blk too big");
87 	*ap->a_bpp = NULL;
88 	if (lbn < 0)
89 		return (EFBIG);
90 	cred = ap->a_cred;
91 	flags = ap->a_flags;
92 
93 	/*
94 	 * If the next write will extend the file into a new block,
95 	 * and the file is currently composed of a fragment
96 	 * this fragment has to be extended to be a full block.
97 	 */
98 	nb = lblkno(fs, ip->i_size);
99 	if (nb < NDADDR && nb < lbn) {
100 		osize = blksize(fs, ip, nb);
101 		if (osize < fs->fs_bsize && osize > 0) {
102 			error = ffs_realloccg(ip, nb,
103 				ffs_blkpref(ip, nb, (int)nb, &ip->i_db[0]),
104 				osize, (int)fs->fs_bsize, cred, &bp);
105 			if (error)
106 				return (error);
107 			if (DOINGSOFTDEP(vp))
108 				softdep_setup_allocdirect(ip, nb,
109 				    dbtofsb(fs, bp->b_blkno), ip->i_db[nb],
110 				    fs->fs_bsize, osize, bp);
111 			ip->i_size = smalllblktosize(fs, nb + 1);
112 			ip->i_db[nb] = dbtofsb(fs, bp->b_blkno);
113 			ip->i_flag |= IN_CHANGE | IN_UPDATE;
114 			if (flags & B_SYNC)
115 				bwrite(bp);
116 			else
117 				bawrite(bp);
118 		}
119 	}
120 	/*
121 	 * The first NDADDR blocks are direct blocks
122 	 */
123 	if (lbn < NDADDR) {
124 		nb = ip->i_db[lbn];
125 		if (nb != 0 && ip->i_size >= smalllblktosize(fs, lbn + 1)) {
126 			error = bread(vp, lbn, fs->fs_bsize, &bp);
127 			if (error) {
128 				brelse(bp);
129 				return (error);
130 			}
131 			bp->b_blkno = fsbtodb(fs, nb);
132 			*ap->a_bpp = bp;
133 			return (0);
134 		}
135 		if (nb != 0) {
136 			/*
137 			 * Consider need to reallocate a fragment.
138 			 */
139 			osize = fragroundup(fs, blkoff(fs, ip->i_size));
140 			nsize = fragroundup(fs, size);
141 			if (nsize <= osize) {
142 				error = bread(vp, lbn, osize, &bp);
143 				if (error) {
144 					brelse(bp);
145 					return (error);
146 				}
147 				bp->b_blkno = fsbtodb(fs, nb);
148 			} else {
149 				error = ffs_realloccg(ip, lbn,
150 				    ffs_blkpref(ip, lbn, (int)lbn,
151 					&ip->i_db[0]), osize, nsize, cred, &bp);
152 				if (error)
153 					return (error);
154 				if (DOINGSOFTDEP(vp))
155 					softdep_setup_allocdirect(ip, lbn,
156 					    dbtofsb(fs, bp->b_blkno), nb,
157 					    nsize, osize, bp);
158 			}
159 		} else {
160 			if (ip->i_size < smalllblktosize(fs, lbn + 1))
161 				nsize = fragroundup(fs, size);
162 			else
163 				nsize = fs->fs_bsize;
164 			error = ffs_alloc(ip, lbn,
165 			    ffs_blkpref(ip, lbn, (int)lbn, &ip->i_db[0]),
166 			    nsize, cred, &newb);
167 			if (error)
168 				return (error);
169 			bp = getblk(vp, lbn, nsize, 0, 0);
170 			bp->b_blkno = fsbtodb(fs, newb);
171 			if (flags & B_CLRBUF)
172 				vfs_bio_clrbuf(bp);
173 			if (DOINGSOFTDEP(vp))
174 				softdep_setup_allocdirect(ip, lbn, newb, 0,
175 				    nsize, 0, bp);
176 		}
177 		ip->i_db[lbn] = dbtofsb(fs, bp->b_blkno);
178 		ip->i_flag |= IN_CHANGE | IN_UPDATE;
179 		*ap->a_bpp = bp;
180 		return (0);
181 	}
182 	/*
183 	 * Determine the number of levels of indirection.
184 	 */
185 	pref = 0;
186 	if ((error = ufs_getlbns(vp, lbn, indirs, &num)) != 0)
187 		return(error);
188 #ifdef DIAGNOSTIC
189 	if (num < 1)
190 		panic ("ffs_balloc: ufs_bmaparray returned indirect block");
191 #endif
192 	/*
193 	 * Fetch the first indirect block allocating if necessary.
194 	 */
195 	--num;
196 	nb = ip->i_ib[indirs[0].in_off];
197 	allocib = NULL;
198 	allocblk = allociblk;
199 	if (nb == 0) {
200 		pref = ffs_blkpref(ip, lbn, 0, (ufs_daddr_t *)0);
201 	        if ((error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize,
202 		    cred, &newb)) != 0)
203 			return (error);
204 		nb = newb;
205 		*allocblk++ = nb;
206 		bp = getblk(vp, indirs[1].in_lbn, fs->fs_bsize, 0, 0);
207 		bp->b_blkno = fsbtodb(fs, nb);
208 		vfs_bio_clrbuf(bp);
209 		if (DOINGSOFTDEP(vp)) {
210 			softdep_setup_allocdirect(ip, NDADDR + indirs[0].in_off,
211 			    newb, 0, fs->fs_bsize, 0, bp);
212 			bdwrite(bp);
213 		} else {
214 			/*
215 			 * Write synchronously so that indirect blocks
216 			 * never point at garbage.
217 			 */
218 			if (DOINGASYNC(vp))
219 				bdwrite(bp);
220 			else if ((error = bwrite(bp)) != 0)
221 				goto fail;
222 		}
223 		allocib = &ip->i_ib[indirs[0].in_off];
224 		*allocib = nb;
225 		ip->i_flag |= IN_CHANGE | IN_UPDATE;
226 	}
227 	/*
228 	 * Fetch through the indirect blocks, allocating as necessary.
229 	 */
230 	for (i = 1;;) {
231 		error = bread(vp, indirs[i].in_lbn, (int)fs->fs_bsize, &bp);
232 		if (error) {
233 			brelse(bp);
234 			goto fail;
235 		}
236 		bap = (ufs_daddr_t *)bp->b_data;
237 		nb = bap[indirs[i].in_off];
238 		if (i == num)
239 			break;
240 		i += 1;
241 		if (nb != 0) {
242 			bqrelse(bp);
243 			continue;
244 		}
245 		if (pref == 0)
246 			pref = ffs_blkpref(ip, lbn, 0, (ufs_daddr_t *)0);
247 		if ((error =
248 		    ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, cred, &newb)) != 0) {
249 			brelse(bp);
250 			goto fail;
251 		}
252 		nb = newb;
253 		*allocblk++ = nb;
254 		nbp = getblk(vp, indirs[i].in_lbn, fs->fs_bsize, 0, 0);
255 		nbp->b_blkno = fsbtodb(fs, nb);
256 		vfs_bio_clrbuf(nbp);
257 		if (DOINGSOFTDEP(vp)) {
258 			softdep_setup_allocindir_meta(nbp, ip, bp,
259 			    indirs[i - 1].in_off, nb);
260 			bdwrite(nbp);
261 		} else {
262 			/*
263 			 * Write synchronously so that indirect blocks
264 			 * never point at garbage.
265 			 */
266 			if ((error = bwrite(nbp)) != 0) {
267 				brelse(bp);
268 				goto fail;
269 			}
270 		}
271 		bap[indirs[i - 1].in_off] = nb;
272 		if (allocib == NULL && unwindidx < 0)
273 			unwindidx = i - 1;
274 		/*
275 		 * If required, write synchronously, otherwise use
276 		 * delayed write.
277 		 */
278 		if (flags & B_SYNC) {
279 			bwrite(bp);
280 		} else {
281 			if (bp->b_bufsize == fs->fs_bsize)
282 				bp->b_flags |= B_CLUSTEROK;
283 			bdwrite(bp);
284 		}
285 	}
286 	/*
287 	 * Get the data block, allocating if necessary.
288 	 */
289 	if (nb == 0) {
290 		pref = ffs_blkpref(ip, lbn, indirs[i].in_off, &bap[0]);
291 		error = ffs_alloc(ip,
292 		    lbn, pref, (int)fs->fs_bsize, cred, &newb);
293 		if (error) {
294 			brelse(bp);
295 			goto fail;
296 		}
297 		nb = newb;
298 		*allocblk++ = nb;
299 		nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0);
300 		nbp->b_blkno = fsbtodb(fs, nb);
301 		if (flags & B_CLRBUF)
302 			vfs_bio_clrbuf(nbp);
303 		if (DOINGSOFTDEP(vp))
304 			softdep_setup_allocindir_page(ip, lbn, bp,
305 			    indirs[i].in_off, nb, 0, nbp);
306 		bap[indirs[i].in_off] = nb;
307 		/*
308 		 * If required, write synchronously, otherwise use
309 		 * delayed write.
310 		 */
311 		if (flags & B_SYNC) {
312 			bwrite(bp);
313 		} else {
314 			if (bp->b_bufsize == fs->fs_bsize)
315 				bp->b_flags |= B_CLUSTEROK;
316 			bdwrite(bp);
317 		}
318 		*ap->a_bpp = nbp;
319 		return (0);
320 	}
321 	brelse(bp);
322 	/*
323 	 * If requested clear invalid portions of the buffer.  If we
324 	 * have to do a read-before-write (typical if B_CLRBUF is set),
325 	 * try to do some read-ahead in the sequential case to reduce
326 	 * the number of I/O transactions.
327 	 */
328 	if (flags & B_CLRBUF) {
329 		int seqcount = (flags & B_SEQMASK) >> B_SEQSHIFT;
330 		if (seqcount &&
331 		    (vp->v_mount->mnt_flag & MNT_NOCLUSTERR) == 0) {
332 			error = cluster_read(vp, ip->i_size, lbn,
333 				    (int)fs->fs_bsize,
334 				    MAXBSIZE, seqcount, &nbp);
335 		} else {
336 			error = bread(vp, lbn, (int)fs->fs_bsize, &nbp);
337 		}
338 		if (error) {
339 			brelse(nbp);
340 			goto fail;
341 		}
342 	} else {
343 		nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0);
344 		nbp->b_blkno = fsbtodb(fs, nb);
345 	}
346 	*ap->a_bpp = nbp;
347 	return (0);
348 fail:
349 	/*
350 	 * If we have failed part way through block allocation, we
351 	 * have to deallocate any indirect blocks that we have allocated.
352 	 * We have to fsync the file before we start to get rid of all
353 	 * of its dependencies so that we do not leave them dangling.
354 	 * We have to sync it at the end so that the soft updates code
355 	 * does not find any untracked changes. Although this is really
356 	 * slow, running out of disk space is not expected to be a common
357 	 * occurence. The error return from fsync is ignored as we already
358 	 * have an error to return to the user.
359 	 */
360 	(void) VOP_FSYNC(vp, MNT_WAIT, td);
361 	for (deallocated = 0, blkp = allociblk; blkp < allocblk; blkp++) {
362 		ffs_blkfree(ip, *blkp, fs->fs_bsize);
363 		deallocated += fs->fs_bsize;
364 	}
365 	if (allocib != NULL) {
366 		*allocib = 0;
367 	} else if (unwindidx >= 0) {
368 		int r;
369 
370 		r = bread(vp, indirs[unwindidx].in_lbn, (int)fs->fs_bsize, &bp);
371 		if (r) {
372 			panic("Could not unwind indirect block, error %d", r);
373 			brelse(bp);
374 		} else {
375 			bap = (ufs_daddr_t *)bp->b_data;
376 			bap[indirs[unwindidx].in_off] = 0;
377 			if (flags & B_SYNC) {
378 				bwrite(bp);
379 			} else {
380 				if (bp->b_bufsize == fs->fs_bsize)
381 					bp->b_flags |= B_CLUSTEROK;
382 				bdwrite(bp);
383 			}
384 		}
385 	}
386 	if (deallocated) {
387 #ifdef QUOTA
388 		/*
389 		 * Restore user's disk quota because allocation failed.
390 		 */
391 		(void) chkdq(ip, (long)-btodb(deallocated), cred, FORCE);
392 #endif
393 		ip->i_blocks -= btodb(deallocated);
394 		ip->i_flag |= IN_CHANGE | IN_UPDATE;
395 	}
396 	(void) VOP_FSYNC(vp, MNT_WAIT, td);
397 	return (error);
398 }
399