1/*	$NetBSD: lfs_balloc.c,v 1.69 2010/02/16 23:20:30 mlelstv Exp $	*/
2
3/*-
4 * Copyright (c) 1999, 2000, 2001, 2002, 2003 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Konrad E. Schroder <perseant@hhhh.org>.
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 * Copyright (c) 1989, 1991, 1993
33 *	The Regents of the University of California.  All rights reserved.
34 *
35 * Redistribution and use in source and binary forms, with or without
36 * modification, are permitted provided that the following conditions
37 * are met:
38 * 1. Redistributions of source code must retain the above copyright
39 *    notice, this list of conditions and the following disclaimer.
40 * 2. Redistributions in binary form must reproduce the above copyright
41 *    notice, this list of conditions and the following disclaimer in the
42 *    documentation and/or other materials provided with the distribution.
43 * 3. Neither the name of the University nor the names of its contributors
44 *    may be used to endorse or promote products derived from this software
45 *    without specific prior written permission.
46 *
47 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
48 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
49 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
50 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
51 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
52 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
53 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
54 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
55 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
56 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
57 * SUCH DAMAGE.
58 *
59 *	@(#)lfs_balloc.c	8.4 (Berkeley) 5/8/95
60 */
61
62#include <sys/cdefs.h>
63__KERNEL_RCSID(0, "$NetBSD: lfs_balloc.c,v 1.69 2010/02/16 23:20:30 mlelstv Exp $");
64
65#if defined(_KERNEL_OPT)
66#include "opt_quota.h"
67#endif
68
69#include <sys/param.h>
70#include <sys/systm.h>
71#include <sys/buf.h>
72#include <sys/proc.h>
73#include <sys/vnode.h>
74#include <sys/mount.h>
75#include <sys/resourcevar.h>
76#include <sys/tree.h>
77#include <sys/trace.h>
78#include <sys/kauth.h>
79
80#include <miscfs/specfs/specdev.h>
81
82#include <ufs/ufs/quota.h>
83#include <ufs/ufs/inode.h>
84#include <ufs/ufs/ufsmount.h>
85#include <ufs/ufs/ufs_extern.h>
86
87#include <ufs/lfs/lfs.h>
88#include <ufs/lfs/lfs_extern.h>
89
90#include <uvm/uvm.h>
91
92int lfs_fragextend(struct vnode *, int, int, daddr_t, struct buf **, kauth_cred_t);
93
94u_int64_t locked_fakequeue_count;
95
96/*
97 * Allocate a block, and to inode and filesystem block accounting for it
98 * and for any indirect blocks the may need to be created in order for
99 * this block to be created.
100 *
101 * Blocks which have never been accounted for (i.e., which "do not exist")
102 * have disk address 0, which is translated by ufs_bmap to the special value
103 * UNASSIGNED == -1, as in the historical UFS.
104 *
105 * Blocks which have been accounted for but which have not yet been written
106 * to disk are given the new special disk address UNWRITTEN == -2, so that
107 * they can be differentiated from completely new blocks.
108 */
109/* VOP_BWRITE NIADDR+2 times */
110int
111lfs_balloc(struct vnode *vp, off_t startoffset, int iosize, kauth_cred_t cred,
112    int flags, struct buf **bpp)
113{
114	int offset;
115	daddr_t daddr, idaddr;
116	struct buf *ibp, *bp;
117	struct inode *ip;
118	struct lfs *fs;
119	struct indir indirs[NIADDR+2], *idp;
120	daddr_t	lbn, lastblock;
121	int bcount;
122	int error, frags, i, nsize, osize, num;
123
124	ip = VTOI(vp);
125	fs = ip->i_lfs;
126	offset = blkoff(fs, startoffset);
127	KASSERT(iosize <= fs->lfs_bsize);
128	lbn = lblkno(fs, startoffset);
129	/* (void)lfs_check(vp, lbn, 0); */
130
131	ASSERT_MAYBE_SEGLOCK(fs);
132
133	/*
134	 * Three cases: it's a block beyond the end of file, it's a block in
135	 * the file that may or may not have been assigned a disk address or
136	 * we're writing an entire block.
137	 *
138	 * Note, if the daddr is UNWRITTEN, the block already exists in
139	 * the cache (it was read or written earlier).	If so, make sure
140	 * we don't count it as a new block or zero out its contents. If
141	 * it did not, make sure we allocate any necessary indirect
142	 * blocks.
143	 *
144	 * If we are writing a block beyond the end of the file, we need to
145	 * check if the old last block was a fragment.	If it was, we need
146	 * to rewrite it.
147	 */
148
149	if (bpp)
150		*bpp = NULL;
151
152	/* Check for block beyond end of file and fragment extension needed. */
153	lastblock = lblkno(fs, ip->i_size);
154	if (lastblock < NDADDR && lastblock < lbn) {
155		osize = blksize(fs, ip, lastblock);
156		if (osize < fs->lfs_bsize && osize > 0) {
157			if ((error = lfs_fragextend(vp, osize, fs->lfs_bsize,
158						    lastblock,
159						    (bpp ? &bp : NULL), cred)))
160				return (error);
161			ip->i_ffs1_size = ip->i_size =
162			    (lastblock + 1) * fs->lfs_bsize;
163			uvm_vnp_setsize(vp, ip->i_size);
164			ip->i_flag |= IN_CHANGE | IN_UPDATE;
165			if (bpp)
166				(void) VOP_BWRITE(bp->b_vp, bp);
167		}
168	}
169
170	/*
171	 * If the block we are writing is a direct block, it's the last
172	 * block in the file, and offset + iosize is less than a full
173	 * block, we can write one or more fragments.  There are two cases:
174	 * the block is brand new and we should allocate it the correct
175	 * size or it already exists and contains some fragments and
176	 * may need to extend it.
177	 */
178	if (lbn < NDADDR && lblkno(fs, ip->i_size) <= lbn) {
179		osize = blksize(fs, ip, lbn);
180		nsize = fragroundup(fs, offset + iosize);
181		if (lblktosize(fs, lbn) >= ip->i_size) {
182			/* Brand new block or fragment */
183			frags = numfrags(fs, nsize);
184			if (!ISSPACE(fs, frags, cred))
185				return ENOSPC;
186			if (bpp) {
187				*bpp = bp = getblk(vp, lbn, nsize, 0, 0);
188				bp->b_blkno = UNWRITTEN;
189				if (flags & B_CLRBUF)
190					clrbuf(bp);
191			}
192			ip->i_lfs_effnblks += frags;
193			mutex_enter(&lfs_lock);
194			fs->lfs_bfree -= frags;
195			mutex_exit(&lfs_lock);
196			ip->i_ffs1_db[lbn] = UNWRITTEN;
197		} else {
198			if (nsize <= osize) {
199				/* No need to extend */
200				if (bpp && (error = bread(vp, lbn, osize,
201				    NOCRED, 0, &bp)))
202					return error;
203			} else {
204				/* Extend existing block */
205				if ((error =
206				     lfs_fragextend(vp, osize, nsize, lbn,
207						    (bpp ? &bp : NULL), cred)))
208					return error;
209			}
210			if (bpp)
211				*bpp = bp;
212		}
213		return 0;
214	}
215
216	error = ufs_bmaparray(vp, lbn, &daddr, &indirs[0], &num, NULL, NULL);
217	if (error)
218		return (error);
219
220	daddr = (daddr_t)((int32_t)daddr); /* XXX ondisk32 */
221	KASSERT(daddr <= LFS_MAX_DADDR);
222
223	/*
224	 * Do byte accounting all at once, so we can gracefully fail *before*
225	 * we start assigning blocks.
226	 */
227	frags = VFSTOUFS(vp->v_mount)->um_seqinc;
228	bcount = 0;
229	if (daddr == UNASSIGNED) {
230		bcount = frags;
231	}
232	for (i = 1; i < num; ++i) {
233		if (!indirs[i].in_exists) {
234			bcount += frags;
235		}
236	}
237	if (ISSPACE(fs, bcount, cred)) {
238		mutex_enter(&lfs_lock);
239		fs->lfs_bfree -= bcount;
240		mutex_exit(&lfs_lock);
241		ip->i_lfs_effnblks += bcount;
242	} else {
243		return ENOSPC;
244	}
245
246	if (daddr == UNASSIGNED) {
247		if (num > 0 && ip->i_ffs1_ib[indirs[0].in_off] == 0) {
248			ip->i_ffs1_ib[indirs[0].in_off] = UNWRITTEN;
249		}
250
251		/*
252		 * Create new indirect blocks if necessary
253		 */
254		if (num > 1) {
255			idaddr = ip->i_ffs1_ib[indirs[0].in_off];
256			for (i = 1; i < num; ++i) {
257				ibp = getblk(vp, indirs[i].in_lbn,
258				    fs->lfs_bsize, 0,0);
259				if (!indirs[i].in_exists) {
260					clrbuf(ibp);
261					ibp->b_blkno = UNWRITTEN;
262				} else if (!(ibp->b_oflags & (BO_DELWRI | BO_DONE))) {
263					ibp->b_blkno = fsbtodb(fs, idaddr);
264					ibp->b_flags |= B_READ;
265					VOP_STRATEGY(vp, ibp);
266					biowait(ibp);
267				}
268				/*
269				 * This block exists, but the next one may not.
270				 * If that is the case mark it UNWRITTEN to keep
271				 * the accounting straight.
272				 */
273				/* XXX ondisk32 */
274				if (((int32_t *)ibp->b_data)[indirs[i].in_off] == 0)
275					((int32_t *)ibp->b_data)[indirs[i].in_off] =
276						UNWRITTEN;
277				/* XXX ondisk32 */
278				idaddr = ((int32_t *)ibp->b_data)[indirs[i].in_off];
279#ifdef DEBUG
280				if (vp == fs->lfs_ivnode) {
281					LFS_ENTER_LOG("balloc", __FILE__,
282						__LINE__, indirs[i].in_lbn,
283						ibp->b_flags, curproc->p_pid);
284				}
285#endif
286				if ((error = VOP_BWRITE(ibp->b_vp, ibp)))
287					return error;
288			}
289		}
290	}
291
292
293	/*
294	 * Get the existing block from the cache, if requested.
295	 */
296	if (bpp)
297		*bpp = bp = getblk(vp, lbn, blksize(fs, ip, lbn), 0, 0);
298
299	/*
300	 * Do accounting on blocks that represent pages.
301	 */
302	if (!bpp)
303		lfs_register_block(vp, lbn);
304
305	/*
306	 * The block we are writing may be a brand new block
307	 * in which case we need to do accounting.
308	 *
309	 * We can tell a truly new block because ufs_bmaparray will say
310	 * it is UNASSIGNED.  Once we allocate it we will assign it the
311	 * disk address UNWRITTEN.
312	 */
313	if (daddr == UNASSIGNED) {
314		if (bpp) {
315			if (flags & B_CLRBUF)
316				clrbuf(bp);
317
318			/* Note the new address */
319			bp->b_blkno = UNWRITTEN;
320		}
321
322		switch (num) {
323		    case 0:
324			ip->i_ffs1_db[lbn] = UNWRITTEN;
325			break;
326		    case 1:
327			ip->i_ffs1_ib[indirs[0].in_off] = UNWRITTEN;
328			break;
329		    default:
330			idp = &indirs[num - 1];
331			if (bread(vp, idp->in_lbn, fs->lfs_bsize, NOCRED,
332				  B_MODIFY, &ibp))
333				panic("lfs_balloc: bread bno %lld",
334				    (long long)idp->in_lbn);
335			/* XXX ondisk32 */
336			((int32_t *)ibp->b_data)[idp->in_off] = UNWRITTEN;
337#ifdef DEBUG
338			if (vp == fs->lfs_ivnode) {
339				LFS_ENTER_LOG("balloc", __FILE__,
340					__LINE__, idp->in_lbn,
341					ibp->b_flags, curproc->p_pid);
342			}
343#endif
344			VOP_BWRITE(ibp->b_vp, ibp);
345		}
346	} else if (bpp && !(bp->b_oflags & (BO_DONE|BO_DELWRI))) {
347		/*
348		 * Not a brand new block, also not in the cache;
349		 * read it in from disk.
350		 */
351		if (iosize == fs->lfs_bsize)
352			/* Optimization: I/O is unnecessary. */
353			bp->b_blkno = daddr;
354		else {
355			/*
356			 * We need to read the block to preserve the
357			 * existing bytes.
358			 */
359			bp->b_blkno = daddr;
360			bp->b_flags |= B_READ;
361			VOP_STRATEGY(vp, bp);
362			return (biowait(bp));
363		}
364	}
365
366	return (0);
367}
368
369/* VOP_BWRITE 1 time */
370int
371lfs_fragextend(struct vnode *vp, int osize, int nsize, daddr_t lbn, struct buf **bpp,
372    kauth_cred_t cred)
373{
374	struct inode *ip;
375	struct lfs *fs;
376	long frags;
377	int error;
378	extern long locked_queue_bytes;
379	size_t obufsize;
380
381	ip = VTOI(vp);
382	fs = ip->i_lfs;
383	frags = (long)numfrags(fs, nsize - osize);
384	error = 0;
385
386	ASSERT_NO_SEGLOCK(fs);
387
388	/*
389	 * Get the seglock so we don't enlarge blocks while a segment
390	 * is being written.  If we're called with bpp==NULL, though,
391	 * we are only pretending to change a buffer, so we don't have to
392	 * lock.
393	 */
394    top:
395	if (bpp) {
396		rw_enter(&fs->lfs_fraglock, RW_READER);
397		LFS_DEBUG_COUNTLOCKED("frag");
398	}
399
400	if (!ISSPACE(fs, frags, cred)) {
401		error = ENOSPC;
402		goto out;
403	}
404
405	/*
406	 * If we are not asked to actually return the block, all we need
407	 * to do is allocate space for it.  UBC will handle dirtying the
408	 * appropriate things and making sure it all goes to disk.
409	 * Don't bother to read in that case.
410	 */
411	if (bpp && (error = bread(vp, lbn, osize, NOCRED, 0, bpp))) {
412		brelse(*bpp, 0);
413		goto out;
414	}
415#ifdef QUOTA
416	if ((error = chkdq(ip, frags, cred, 0))) {
417		if (bpp)
418			brelse(*bpp, 0);
419		goto out;
420	}
421#endif
422	/*
423	 * Adjust accounting for lfs_avail.  If there's not enough room,
424	 * we will have to wait for the cleaner, which we can't do while
425	 * holding a block busy or while holding the seglock.  In that case,
426	 * release both and start over after waiting.
427	 */
428
429	if (bpp && ((*bpp)->b_oflags & BO_DELWRI)) {
430		if (!lfs_fits(fs, frags)) {
431			if (bpp)
432				brelse(*bpp, 0);
433#ifdef QUOTA
434			chkdq(ip, -frags, cred, 0);
435#endif
436			rw_exit(&fs->lfs_fraglock);
437			lfs_availwait(fs, frags);
438			goto top;
439		}
440		fs->lfs_avail -= frags;
441	}
442
443	mutex_enter(&lfs_lock);
444	fs->lfs_bfree -= frags;
445	mutex_exit(&lfs_lock);
446	ip->i_lfs_effnblks += frags;
447	ip->i_flag |= IN_CHANGE | IN_UPDATE;
448
449	if (bpp) {
450		obufsize = (*bpp)->b_bufsize;
451		allocbuf(*bpp, nsize, 1);
452
453		/* Adjust locked-list accounting */
454		if (((*bpp)->b_flags & B_LOCKED) != 0 &&
455		    (*bpp)->b_iodone == NULL) {
456			mutex_enter(&lfs_lock);
457			locked_queue_bytes += (*bpp)->b_bufsize - obufsize;
458			mutex_exit(&lfs_lock);
459		}
460
461		memset((char *)((*bpp)->b_data) + osize, 0, (u_int)(nsize - osize));
462	}
463
464    out:
465	if (bpp) {
466		rw_exit(&fs->lfs_fraglock);
467	}
468	return (error);
469}
470
471static inline int
472lge(struct lbnentry *a, struct lbnentry *b)
473{
474	return a->lbn - b->lbn;
475}
476
477SPLAY_PROTOTYPE(lfs_splay, lbnentry, entry, lge);
478
479SPLAY_GENERATE(lfs_splay, lbnentry, entry, lge);
480
481/*
482 * Record this lbn as being "write pending".  We used to have this information
483 * on the buffer headers, but since pages don't have buffer headers we
484 * record it here instead.
485 */
486void
487lfs_register_block(struct vnode *vp, daddr_t lbn)
488{
489	struct lfs *fs;
490	struct inode *ip;
491	struct lbnentry *lbp;
492
493	ip = VTOI(vp);
494
495	/* Don't count metadata */
496	if (lbn < 0 || vp->v_type != VREG || ip->i_number == LFS_IFILE_INUM)
497		return;
498
499	fs = ip->i_lfs;
500
501	ASSERT_NO_SEGLOCK(fs);
502
503	/* If no space, wait for the cleaner */
504	lfs_availwait(fs, btofsb(fs, 1 << fs->lfs_bshift));
505
506	lbp = (struct lbnentry *)pool_get(&lfs_lbnentry_pool, PR_WAITOK);
507	lbp->lbn = lbn;
508	mutex_enter(&lfs_lock);
509	if (SPLAY_INSERT(lfs_splay, &ip->i_lfs_lbtree, lbp) != NULL) {
510		mutex_exit(&lfs_lock);
511		/* Already there */
512		pool_put(&lfs_lbnentry_pool, lbp);
513		return;
514	}
515
516	++ip->i_lfs_nbtree;
517	fs->lfs_favail += btofsb(fs, (1 << fs->lfs_bshift));
518	fs->lfs_pages += fs->lfs_bsize >> PAGE_SHIFT;
519	++locked_fakequeue_count;
520	lfs_subsys_pages += fs->lfs_bsize >> PAGE_SHIFT;
521	mutex_exit(&lfs_lock);
522}
523
524static void
525lfs_do_deregister(struct lfs *fs, struct inode *ip, struct lbnentry *lbp)
526{
527	ASSERT_MAYBE_SEGLOCK(fs);
528
529	mutex_enter(&lfs_lock);
530	--ip->i_lfs_nbtree;
531	SPLAY_REMOVE(lfs_splay, &ip->i_lfs_lbtree, lbp);
532	if (fs->lfs_favail > btofsb(fs, (1 << fs->lfs_bshift)))
533		fs->lfs_favail -= btofsb(fs, (1 << fs->lfs_bshift));
534	fs->lfs_pages -= fs->lfs_bsize >> PAGE_SHIFT;
535	if (locked_fakequeue_count > 0)
536		--locked_fakequeue_count;
537	lfs_subsys_pages -= fs->lfs_bsize >> PAGE_SHIFT;
538	mutex_exit(&lfs_lock);
539
540	pool_put(&lfs_lbnentry_pool, lbp);
541}
542
543void
544lfs_deregister_block(struct vnode *vp, daddr_t lbn)
545{
546	struct lfs *fs;
547	struct inode *ip;
548	struct lbnentry *lbp;
549	struct lbnentry tmp;
550
551	ip = VTOI(vp);
552
553	/* Don't count metadata */
554	if (lbn < 0 || vp->v_type != VREG || ip->i_number == LFS_IFILE_INUM)
555		return;
556
557	fs = ip->i_lfs;
558	tmp.lbn = lbn;
559	lbp = SPLAY_FIND(lfs_splay, &ip->i_lfs_lbtree, &tmp);
560	if (lbp == NULL)
561		return;
562
563	lfs_do_deregister(fs, ip, lbp);
564}
565
566void
567lfs_deregister_all(struct vnode *vp)
568{
569	struct lbnentry *lbp, *nlbp;
570	struct lfs_splay *hd;
571	struct lfs *fs;
572	struct inode *ip;
573
574	ip = VTOI(vp);
575	fs = ip->i_lfs;
576	hd = &ip->i_lfs_lbtree;
577
578	for (lbp = SPLAY_MIN(lfs_splay, hd); lbp != NULL; lbp = nlbp) {
579		nlbp = SPLAY_NEXT(lfs_splay, hd, lbp);
580		lfs_do_deregister(fs, ip, lbp);
581	}
582}
583