lfs_subr.c revision 1.36
1/*	$NetBSD: lfs_subr.c,v 1.36 2003/03/08 02:55:49 perseant 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 * 3. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *	This product includes software developed by the NetBSD
21 *	Foundation, Inc. and its contributors.
22 * 4. Neither the name of The NetBSD Foundation nor the names of its
23 *    contributors may be used to endorse or promote products derived
24 *    from this software without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 * POSSIBILITY OF SUCH DAMAGE.
37 */
38/*
39 * Copyright (c) 1991, 1993
40 *	The Regents of the University of California.  All rights reserved.
41 *
42 * Redistribution and use in source and binary forms, with or without
43 * modification, are permitted provided that the following conditions
44 * are met:
45 * 1. Redistributions of source code must retain the above copyright
46 *    notice, this list of conditions and the following disclaimer.
47 * 2. Redistributions in binary form must reproduce the above copyright
48 *    notice, this list of conditions and the following disclaimer in the
49 *    documentation and/or other materials provided with the distribution.
50 * 3. All advertising materials mentioning features or use of this software
51 *    must display the following acknowledgement:
52 *	This product includes software developed by the University of
53 *	California, Berkeley and its contributors.
54 * 4. Neither the name of the University nor the names of its contributors
55 *    may be used to endorse or promote products derived from this software
56 *    without specific prior written permission.
57 *
58 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
59 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
60 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
61 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
62 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
63 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
64 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
65 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
66 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
67 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
68 * SUCH DAMAGE.
69 *
70 *	@(#)lfs_subr.c	8.4 (Berkeley) 5/8/95
71 */
72
73#include <sys/cdefs.h>
74__KERNEL_RCSID(0, "$NetBSD: lfs_subr.c,v 1.36 2003/03/08 02:55:49 perseant Exp $");
75
76#include <sys/param.h>
77#include <sys/systm.h>
78#include <sys/namei.h>
79#include <sys/vnode.h>
80#include <sys/buf.h>
81#include <sys/mount.h>
82#include <sys/malloc.h>
83#include <sys/proc.h>
84
85#include <ufs/ufs/inode.h>
86#include <ufs/lfs/lfs.h>
87#include <ufs/lfs/lfs_extern.h>
88
89#include <uvm/uvm.h>
90
91/*
92 * Return buffer with the contents of block "offset" from the beginning of
93 * directory "ip".  If "res" is non-zero, fill it in with a pointer to the
94 * remaining space in the directory.
95 */
96int
97lfs_blkatoff(void *v)
98{
99	struct vop_blkatoff_args /* {
100		struct vnode *a_vp;
101		off_t a_offset;
102		char **a_res;
103		struct buf **a_bpp;
104		} */ *ap = v;
105	struct lfs *fs;
106	struct inode *ip;
107	struct buf *bp;
108	daddr_t lbn;
109	int bsize, error;
110
111	ip = VTOI(ap->a_vp);
112	fs = ip->i_lfs;
113	lbn = lblkno(fs, ap->a_offset);
114	bsize = blksize(fs, ip, lbn);
115
116	*ap->a_bpp = NULL;
117	if ((error = bread(ap->a_vp, lbn, bsize, NOCRED, &bp)) != 0) {
118		brelse(bp);
119		return (error);
120	}
121	if (ap->a_res)
122		*ap->a_res = (char *)bp->b_data + blkoff(fs, ap->a_offset);
123	*ap->a_bpp = bp;
124	return (0);
125}
126
127#ifdef LFS_DEBUG_MALLOC
128char *lfs_res_names[LFS_NB_COUNT] = {
129	"summary",
130	"superblock",
131	"ifile block",
132	"cluster",
133	"clean",
134};
135#endif
136
137int lfs_res_qty[LFS_NB_COUNT] = {
138	LFS_N_SUMMARIES,
139	LFS_N_SBLOCKS,
140	LFS_N_IBLOCKS,
141	LFS_N_CLUSTERS,
142	LFS_N_CLEAN,
143};
144
145void
146lfs_setup_resblks(struct lfs *fs)
147{
148	int i, j;
149	int maxbpp;
150
151	fs->lfs_resblk = (res_t *)malloc(LFS_N_TOTAL * sizeof(res_t), M_SEGMENT,
152					  M_WAITOK);
153	for (i = 0; i < LFS_N_TOTAL; i++) {
154		fs->lfs_resblk[i].inuse = 0;
155		fs->lfs_resblk[i].p = NULL;
156	}
157	for (i = 0; i < LFS_RESHASH_WIDTH; i++)
158		LIST_INIT(fs->lfs_reshash + i);
159
160	/*
161	 * These types of allocations can be larger than a page,
162	 * so we can't use the pool subsystem for them.
163	 */
164	for (i = 0, j = 0; j < LFS_N_SUMMARIES; j++, i++)
165		fs->lfs_resblk[i].size = fs->lfs_sumsize;
166	for (j = 0; j < LFS_N_SBLOCKS; j++, i++)
167		fs->lfs_resblk[i].size = LFS_SBPAD;
168	for (j = 0; j < LFS_N_IBLOCKS; j++, i++)
169		fs->lfs_resblk[i].size = fs->lfs_bsize;
170	for (j = 0; j < LFS_N_CLUSTERS; j++, i++)
171		fs->lfs_resblk[i].size = MAXPHYS;
172	for (j = 0; j < LFS_N_CLEAN; j++, i++)
173		fs->lfs_resblk[i].size = MAXPHYS;
174
175	for (i = 0; i < LFS_N_TOTAL; i++) {
176		fs->lfs_resblk[i].p = malloc(fs->lfs_resblk[i].size,
177					     M_SEGMENT, M_WAITOK);
178	}
179
180	/*
181	 * Initialize pools for small types (XXX is BPP small?)
182	 */
183	pool_init(&fs->lfs_clpool, sizeof(struct lfs_cluster), 0, 0,
184		LFS_N_CL, "lfsclpl", &pool_allocator_nointr);
185	pool_init(&fs->lfs_segpool, sizeof(struct segment), 0, 0,
186		LFS_N_SEG, "lfssegpool", &pool_allocator_nointr);
187	maxbpp = ((fs->lfs_sumsize - SEGSUM_SIZE(fs)) / sizeof(int32_t) + 2);
188	maxbpp = MIN(maxbpp, fs->lfs_ssize / fs->lfs_fsize + 2);
189	pool_init(&fs->lfs_bpppool, maxbpp * sizeof(struct buf *), 0, 0,
190		LFS_N_BPP, "lfsbpppl", &pool_allocator_nointr);
191}
192
193void
194lfs_free_resblks(struct lfs *fs)
195{
196	int i;
197
198	pool_destroy(&fs->lfs_bpppool);
199	pool_destroy(&fs->lfs_segpool);
200	pool_destroy(&fs->lfs_clpool);
201
202	for (i = 0; i < LFS_N_TOTAL; i++) {
203		while(fs->lfs_resblk[i].inuse)
204			tsleep(&fs->lfs_resblk, PRIBIO + 1, "lfs_free", 0);
205		if (fs->lfs_resblk[i].p != NULL)
206			free(fs->lfs_resblk[i].p, M_SEGMENT);
207	}
208	free(fs->lfs_resblk, M_SEGMENT);
209}
210
211static unsigned int
212lfs_mhash(void *vp)
213{
214	return (unsigned int)(((unsigned long)vp) >> 2) % LFS_RESHASH_WIDTH;
215}
216
217/*
218 * Return memory of the given size for the given purpose, or use one of a
219 * number of spare last-resort buffers, if malloc returns NULL.
220 */
221void *
222lfs_malloc(struct lfs *fs, size_t size, int type)
223{
224	struct lfs_res_blk *re;
225	void *r;
226	int i, s, start;
227	unsigned int h;
228
229	r = NULL;
230
231	/* If no mem allocated for this type, it just waits */
232	if (lfs_res_qty[type] == 0) {
233		r = malloc(size, M_SEGMENT, M_WAITOK);
234		return r;
235	}
236
237	/* Otherwise try a quick malloc, and if it works, great */
238	if ((r = malloc(size, M_SEGMENT, M_NOWAIT)) != NULL) {
239		return r;
240	}
241
242	/*
243	 * If malloc returned NULL, we are forced to use one of our
244	 * reserve blocks.  We have on hand at least one summary block,
245	 * at least one cluster block, at least one superblock,
246	 * and several indirect blocks.
247	 */
248	/* skip over blocks of other types */
249	for (i = 0, start = 0; i < type; i++)
250		start += lfs_res_qty[i];
251	while (r == NULL) {
252		for (i = 0; i < lfs_res_qty[type]; i++) {
253			if (fs->lfs_resblk[start + i].inuse == 0) {
254				re = fs->lfs_resblk + start + i;
255				re->inuse = 1;
256				r = re->p;
257				KASSERT(re->size >= size);
258				h = lfs_mhash(r);
259				s = splbio();
260				LIST_INSERT_HEAD(&fs->lfs_reshash[h], re, res);
261				splx(s);
262				return r;
263			}
264		}
265#ifdef LFS_DEBUG_MALLOC
266		printf("sleeping on %s (%d)\n", lfs_res_names[type], lfs_res_qty[type]);
267#endif
268		tsleep(&fs->lfs_resblk, PVM, "lfs_malloc", 0);
269#ifdef LFS_DEBUG_MALLOC
270		printf("done sleeping on %s\n", lfs_res_names[type]);
271#endif
272	}
273	/* NOTREACHED */
274	return r;
275}
276
277void
278lfs_free(struct lfs *fs, void *p, int type)
279{
280	int s;
281	unsigned int h;
282	res_t *re;
283#ifdef DEBUG
284	int i;
285#endif
286
287	h = lfs_mhash(p);
288	s = splbio();
289	LIST_FOREACH(re, &fs->lfs_reshash[h], res) {
290		if (re->p == p) {
291			KASSERT(re->inuse == 1);
292			LIST_REMOVE(re, res);
293			re->inuse = 0;
294			wakeup(&fs->lfs_resblk);
295			splx(s);
296			return;
297		}
298	}
299#ifdef DEBUG
300	for (i = 0; i < LFS_N_TOTAL; i++) {
301		if (fs->lfs_resblk[i].p == p)
302			panic("lfs_free: inconsistent reserved block");
303	}
304#endif
305	splx(s);
306
307	/*
308	 * If we didn't find it, free it.
309	 */
310	free(p, M_SEGMENT);
311}
312
313/*
314 * lfs_seglock --
315 *	Single thread the segment writer.
316 */
317int
318lfs_seglock(struct lfs *fs, unsigned long flags)
319{
320	struct segment *sp;
321
322	if (fs->lfs_seglock) {
323		if (fs->lfs_lockpid == curproc->p_pid) {
324			++fs->lfs_seglock;
325			fs->lfs_sp->seg_flags |= flags;
326			return 0;
327		} else if (flags & SEGM_PAGEDAEMON)
328			return EWOULDBLOCK;
329		else while (fs->lfs_seglock)
330			(void)tsleep(&fs->lfs_seglock, PRIBIO + 1,
331				     "lfs seglock", 0);
332	}
333
334	fs->lfs_seglock = 1;
335	fs->lfs_lockpid = curproc->p_pid;
336	fs->lfs_cleanind = 0;
337
338	/* Drain fragment size changes out */
339	lockmgr(&fs->lfs_fraglock, LK_EXCLUSIVE, 0);
340
341	sp = fs->lfs_sp = pool_get(&fs->lfs_segpool, PR_WAITOK);
342	sp->bpp = pool_get(&fs->lfs_bpppool, PR_WAITOK);
343	sp->seg_flags = flags;
344	sp->vp = NULL;
345	sp->seg_iocount = 0;
346	(void) lfs_initseg(fs);
347
348	/*
349	 * Keep a cumulative count of the outstanding I/O operations.  If the
350	 * disk drive catches up with us it could go to zero before we finish,
351	 * so we artificially increment it by one until we've scheduled all of
352	 * the writes we intend to do.
353	 */
354	++fs->lfs_iocount;
355	return 0;
356}
357
358static void lfs_unmark_dirop(struct lfs *);
359
360static void
361lfs_unmark_dirop(struct lfs *fs)
362{
363	struct inode *ip, *nip;
364	struct vnode *vp;
365	extern int lfs_dirvcount;
366
367	for (ip = TAILQ_FIRST(&fs->lfs_dchainhd); ip != NULL; ip = nip) {
368		nip = TAILQ_NEXT(ip, i_lfs_dchain);
369		vp = ITOV(ip);
370
371		if (VOP_ISLOCKED(vp) &&
372			   vp->v_lock.lk_lockholder != curproc->p_pid) {
373			continue;
374		}
375		if ((VTOI(vp)->i_flag & IN_ADIROP) == 0) {
376			--lfs_dirvcount;
377			vp->v_flag &= ~VDIROP;
378			TAILQ_REMOVE(&fs->lfs_dchainhd, ip, i_lfs_dchain);
379			wakeup(&lfs_dirvcount);
380			fs->lfs_unlockvp = vp;
381			vrele(vp);
382			fs->lfs_unlockvp = NULL;
383		}
384	}
385}
386
387static void
388lfs_auto_segclean(struct lfs *fs)
389{
390	int i, error;
391
392	/*
393	 * Now that we've swapped lfs_activesb, but while we still
394	 * hold the segment lock, run through the segment list marking
395	 * the empty ones clean.
396	 * XXX - do we really need to do them all at once?
397	 */
398	for (i = 0; i < fs->lfs_nseg; i++) {
399		if ((fs->lfs_suflags[0][i] &
400		     (SEGUSE_ACTIVE | SEGUSE_DIRTY | SEGUSE_EMPTY)) ==
401		    (SEGUSE_DIRTY | SEGUSE_EMPTY) &&
402		    (fs->lfs_suflags[1][i] &
403		     (SEGUSE_ACTIVE | SEGUSE_DIRTY | SEGUSE_EMPTY)) ==
404		    (SEGUSE_DIRTY | SEGUSE_EMPTY)) {
405
406			if ((error = lfs_do_segclean(fs, i)) != 0) {
407#ifdef DEBUG
408				printf("lfs_auto_segclean: lfs_do_segclean returned %d for seg %d\n", error, i);
409#endif /* DEBUG */
410			}
411		}
412		fs->lfs_suflags[1 - fs->lfs_activesb][i] =
413			fs->lfs_suflags[fs->lfs_activesb][i];
414	}
415}
416
417/*
418 * lfs_segunlock --
419 *	Single thread the segment writer.
420 */
421void
422lfs_segunlock(struct lfs *fs)
423{
424	struct segment *sp;
425	unsigned long sync, ckp;
426	struct buf *bp;
427#ifdef LFS_MALLOC_SUMMARY
428	extern int locked_queue_count;
429	extern long locked_queue_bytes;
430#endif
431
432	sp = fs->lfs_sp;
433
434	if (fs->lfs_seglock == 1) {
435		if ((sp->seg_flags & SEGM_PROT) == 0)
436			lfs_unmark_dirop(fs);
437		sync = sp->seg_flags & SEGM_SYNC;
438		ckp = sp->seg_flags & SEGM_CKP;
439		if (sp->bpp != sp->cbpp) {
440			/* Free allocated segment summary */
441			fs->lfs_offset -= btofsb(fs, fs->lfs_sumsize);
442			bp = *sp->bpp;
443#ifdef LFS_MALLOC_SUMMARY
444			lfs_freebuf(fs, bp);
445#else
446			s = splbio();
447			bremfree(bp);
448			bp->b_flags |= B_DONE|B_INVAL;
449			bp->b_flags &= ~B_DELWRI;
450			reassignbuf(bp,bp->b_vp);
451			splx(s);
452			brelse(bp);
453#endif
454		} else
455			printf ("unlock to 0 with no summary");
456
457		pool_put(&fs->lfs_bpppool, sp->bpp);
458		sp->bpp = NULL;
459
460		/*
461		 * If we're not sync, we're done with sp, get rid of it.
462		 * Otherwise, we keep a local copy around but free
463		 * fs->lfs_sp so another process can use it (we have to
464		 * wait but they don't have to wait for us).
465		 */
466		if (!sync)
467			pool_put(&fs->lfs_segpool, sp);
468		fs->lfs_sp = NULL;
469
470		/*
471		 * If the I/O count is non-zero, sleep until it reaches zero.
472		 * At the moment, the user's process hangs around so we can
473		 * sleep.
474		 */
475		if (--fs->lfs_iocount == 0) {
476			lfs_countlocked(&locked_queue_count,
477					&locked_queue_bytes, "lfs_segunlock");
478			wakeup(&locked_queue_count);
479		}
480		if (fs->lfs_iocount <= 1)
481			wakeup(&fs->lfs_iocount);
482		/*
483		 * If we're not checkpointing, we don't have to block
484		 * other processes to wait for a synchronous write
485		 * to complete.
486		 */
487		if (!ckp) {
488			--fs->lfs_seglock;
489			fs->lfs_lockpid = 0;
490			wakeup(&fs->lfs_seglock);
491		}
492		/*
493		 * We let checkpoints happen asynchronously.  That means
494		 * that during recovery, we have to roll forward between
495		 * the two segments described by the first and second
496		 * superblocks to make sure that the checkpoint described
497		 * by a superblock completed.
498		 */
499		while (ckp && sync && fs->lfs_iocount)
500			(void)tsleep(&fs->lfs_iocount, PRIBIO + 1,
501				     "lfs_iocount", 0);
502		while (sync && sp->seg_iocount) {
503			(void)tsleep(&sp->seg_iocount, PRIBIO + 1,
504				     "seg_iocount", 0);
505			/* printf("sleeping on iocount %x == %d\n", sp, sp->seg_iocount); */
506		}
507		if (sync)
508			pool_put(&fs->lfs_segpool, sp);
509
510		if (ckp) {
511			fs->lfs_nactive = 0;
512			/* If we *know* everything's on disk, write both sbs */
513			/* XXX should wait for this one	 */
514			if (sync)
515				lfs_writesuper(fs, fs->lfs_sboffs[fs->lfs_activesb]);
516			lfs_writesuper(fs, fs->lfs_sboffs[1 - fs->lfs_activesb]);
517			if (!(fs->lfs_ivnode->v_mount->mnt_flag & MNT_UNMOUNT))
518				lfs_auto_segclean(fs);
519			fs->lfs_activesb = 1 - fs->lfs_activesb;
520			--fs->lfs_seglock;
521			fs->lfs_lockpid = 0;
522			wakeup(&fs->lfs_seglock);
523		}
524		/* Reenable fragment size changes */
525		lockmgr(&fs->lfs_fraglock, LK_RELEASE, 0);
526	} else if (fs->lfs_seglock == 0) {
527		panic ("Seglock not held");
528	} else {
529		--fs->lfs_seglock;
530	}
531}
532