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lfs_bio.c revision 1.9.2.1.2.1
      1  1.9.2.1.2.1   thorpej /*	$NetBSD: lfs_bio.c,v 1.9.2.1.2.1 1999/06/21 01:31:08 thorpej Exp $	*/
      2          1.2       cgd 
      3          1.7  perseant /*-
      4          1.7  perseant  * Copyright (c) 1999 The NetBSD Foundation, Inc.
      5          1.7  perseant  * All rights reserved.
      6          1.7  perseant  *
      7          1.7  perseant  * This code is derived from software contributed to The NetBSD Foundation
      8          1.7  perseant  * by Konrad E. Schroder <perseant (at) hhhh.org>.
      9          1.7  perseant  *
     10          1.7  perseant  * Redistribution and use in source and binary forms, with or without
     11          1.7  perseant  * modification, are permitted provided that the following conditions
     12          1.7  perseant  * are met:
     13          1.7  perseant  * 1. Redistributions of source code must retain the above copyright
     14          1.7  perseant  *    notice, this list of conditions and the following disclaimer.
     15          1.7  perseant  * 2. Redistributions in binary form must reproduce the above copyright
     16          1.7  perseant  *    notice, this list of conditions and the following disclaimer in the
     17          1.7  perseant  *    documentation and/or other materials provided with the distribution.
     18          1.7  perseant  * 3. All advertising materials mentioning features or use of this software
     19          1.7  perseant  *    must display the following acknowledgement:
     20          1.7  perseant  *      This product includes software developed by the NetBSD
     21          1.7  perseant  *      Foundation, Inc. and its contributors.
     22          1.7  perseant  * 4. Neither the name of The NetBSD Foundation nor the names of its
     23          1.7  perseant  *    contributors may be used to endorse or promote products derived
     24          1.7  perseant  *    from this software without specific prior written permission.
     25          1.7  perseant  *
     26          1.7  perseant  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     27          1.7  perseant  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     28          1.7  perseant  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     29          1.7  perseant  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     30          1.7  perseant  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     31          1.7  perseant  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     32          1.7  perseant  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     33          1.7  perseant  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     34          1.7  perseant  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     35          1.7  perseant  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     36          1.7  perseant  * POSSIBILITY OF SUCH DAMAGE.
     37          1.7  perseant  */
     38          1.1   mycroft /*
     39          1.1   mycroft  * Copyright (c) 1991, 1993
     40          1.1   mycroft  *	The Regents of the University of California.  All rights reserved.
     41          1.1   mycroft  *
     42          1.1   mycroft  * Redistribution and use in source and binary forms, with or without
     43          1.1   mycroft  * modification, are permitted provided that the following conditions
     44          1.1   mycroft  * are met:
     45          1.1   mycroft  * 1. Redistributions of source code must retain the above copyright
     46          1.1   mycroft  *    notice, this list of conditions and the following disclaimer.
     47          1.1   mycroft  * 2. Redistributions in binary form must reproduce the above copyright
     48          1.1   mycroft  *    notice, this list of conditions and the following disclaimer in the
     49          1.1   mycroft  *    documentation and/or other materials provided with the distribution.
     50          1.1   mycroft  * 3. All advertising materials mentioning features or use of this software
     51          1.1   mycroft  *    must display the following acknowledgement:
     52          1.1   mycroft  *	This product includes software developed by the University of
     53          1.1   mycroft  *	California, Berkeley and its contributors.
     54          1.1   mycroft  * 4. Neither the name of the University nor the names of its contributors
     55          1.1   mycroft  *    may be used to endorse or promote products derived from this software
     56          1.1   mycroft  *    without specific prior written permission.
     57          1.1   mycroft  *
     58          1.1   mycroft  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     59          1.1   mycroft  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     60          1.1   mycroft  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     61          1.1   mycroft  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     62          1.1   mycroft  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     63          1.1   mycroft  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     64          1.1   mycroft  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     65          1.1   mycroft  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     66          1.1   mycroft  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     67          1.1   mycroft  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     68          1.1   mycroft  * SUCH DAMAGE.
     69          1.1   mycroft  *
     70          1.6      fvdl  *	@(#)lfs_bio.c	8.10 (Berkeley) 6/10/95
     71          1.1   mycroft  */
     72          1.1   mycroft 
     73          1.1   mycroft #include <sys/param.h>
     74          1.5  christos #include <sys/systm.h>
     75          1.1   mycroft #include <sys/proc.h>
     76          1.1   mycroft #include <sys/buf.h>
     77          1.1   mycroft #include <sys/vnode.h>
     78          1.1   mycroft #include <sys/resourcevar.h>
     79          1.1   mycroft #include <sys/mount.h>
     80          1.1   mycroft #include <sys/kernel.h>
     81          1.1   mycroft 
     82          1.1   mycroft #include <ufs/ufs/quota.h>
     83          1.1   mycroft #include <ufs/ufs/inode.h>
     84          1.1   mycroft #include <ufs/ufs/ufsmount.h>
     85          1.5  christos #include <ufs/ufs/ufs_extern.h>
     86          1.1   mycroft 
     87          1.7  perseant #include <sys/malloc.h>
     88          1.1   mycroft #include <ufs/lfs/lfs.h>
     89          1.1   mycroft #include <ufs/lfs/lfs_extern.h>
     90          1.1   mycroft 
     91          1.7  perseant /* Macros to clear/set/test flags. */
     92          1.7  perseant # define	SET(t, f)	(t) |= (f)
     93          1.7  perseant # define	CLR(t, f)	(t) &= ~(f)
     94          1.7  perseant # define	ISSET(t, f)	((t) & (f))
     95          1.7  perseant 
     96          1.1   mycroft /*
     97          1.1   mycroft  * LFS block write function.
     98          1.1   mycroft  *
     99          1.1   mycroft  * XXX
    100          1.1   mycroft  * No write cost accounting is done.
    101          1.1   mycroft  * This is almost certainly wrong for synchronous operations and NFS.
    102          1.1   mycroft  */
    103          1.1   mycroft int	lfs_allclean_wakeup;		/* Cleaner wakeup address. */
    104          1.7  perseant int	locked_queue_count   = 0;	/* XXX Count of locked-down buffers. */
    105          1.7  perseant long	locked_queue_bytes   = 0L;	/* XXX Total size of locked buffers. */
    106          1.7  perseant int	lfs_writing          = 0;	/* Set if already kicked off a writer
    107          1.1   mycroft 					   because of buffer space */
    108          1.7  perseant extern int lfs_dostats;
    109          1.7  perseant 
    110          1.7  perseant 
    111          1.1   mycroft /*
    112          1.7  perseant  * #define WRITE_THRESHHOLD    ((nbuf >> 1) - 10)
    113          1.7  perseant  * #define WAIT_THRESHHOLD     (nbuf - (nbuf >> 2) - 10)
    114          1.7  perseant  */
    115          1.7  perseant #define LFS_MAX_BUFS        ((nbuf >> 2) - 10)
    116          1.7  perseant #define LFS_WAIT_BUFS       ((nbuf >> 1) - (nbuf >> 3) - 10)
    117          1.7  perseant /* These are new ... is LFS taking up too much memory in its buffers? */
    118          1.7  perseant #define LFS_MAX_BYTES       (((bufpages >> 2) - 10) * CLBYTES)
    119          1.7  perseant #define LFS_WAIT_BYTES      (((bufpages >> 1) - (bufpages >> 3) - 10) * CLBYTES)
    120          1.7  perseant #define LFS_BUFWAIT         2
    121          1.7  perseant /*
    122          1.7  perseant  *
    123          1.7  perseant  * XXX we don't let meta-data writes run out of space because they can
    124          1.7  perseant  * come from the segment writer.  We need to make sure that there is
    125          1.7  perseant  * enough space reserved so that there's room to write meta-data
    126          1.7  perseant  * blocks.
    127          1.7  perseant  *
    128          1.7  perseant  * Also, we don't let blocks that have come to us from the cleaner
    129          1.7  perseant  * run out of space.
    130          1.7  perseant  */
    131          1.7  perseant #define CANT_WAIT(BP,F) (IS_IFILE((BP)) || (BP)->b_lblkno<0 || ((F) & BW_CLEAN))
    132          1.1   mycroft 
    133          1.1   mycroft int
    134          1.5  christos lfs_bwrite(v)
    135          1.5  christos 	void *v;
    136          1.5  christos {
    137          1.1   mycroft 	struct vop_bwrite_args /* {
    138          1.1   mycroft 		struct buf *a_bp;
    139          1.5  christos 	} */ *ap = v;
    140          1.1   mycroft 	register struct buf *bp = ap->a_bp;
    141          1.7  perseant 
    142          1.7  perseant #ifdef DIAGNOSTIC
    143          1.7  perseant 	if(bp->b_flags & B_ASYNC)
    144          1.7  perseant 		panic("bawrite LFS buffer");
    145          1.7  perseant #endif /* DIAGNOSTIC */
    146          1.7  perseant 	return lfs_bwrite_ext(bp,0);
    147          1.7  perseant }
    148          1.7  perseant 
    149          1.7  perseant /*
    150          1.7  perseant  * Determine if there is enough room currently available to write db
    151          1.7  perseant  * disk blocks.  We need enough blocks for the new blocks, the current
    152          1.7  perseant  * inode blocks, a summary block, plus potentially the ifile inode and
    153          1.7  perseant  * the segment usage table, plus an ifile page.
    154          1.7  perseant  */
    155          1.7  perseant inline static int lfs_fits(struct lfs *fs, int db)
    156          1.7  perseant {
    157          1.7  perseant 	if(((db + (fs->lfs_uinodes + INOPB((fs))) /
    158          1.7  perseant 	     INOPB(fs) + fsbtodb(fs, 1) + LFS_SUMMARY_SIZE / DEV_BSIZE +
    159          1.7  perseant 	     fs->lfs_segtabsz)) >= fs->lfs_avail)
    160          1.7  perseant 	{
    161          1.7  perseant 		return 0;
    162          1.7  perseant 	}
    163          1.7  perseant 
    164          1.7  perseant 	/*
    165          1.7  perseant 	 * Also check the number of segments available for writing.
    166          1.7  perseant 	 * If you don't do this here, it is possible for the *cleaner* to
    167          1.7  perseant 	 * cause us to become starved of segments, by flushing the pending
    168          1.7  perseant 	 * block list.
    169          1.7  perseant 	 *
    170          1.7  perseant 	 * XXX the old lfs_markv did not have this problem.
    171          1.7  perseant 	 */
    172          1.7  perseant 	if (fs->lfs_nclean <= MIN_FREE_SEGS)
    173          1.7  perseant 		return 0;
    174          1.7  perseant 
    175          1.7  perseant 	return 1;
    176          1.7  perseant }
    177          1.7  perseant 
    178          1.7  perseant int
    179          1.7  perseant lfs_bwrite_ext(bp, flags)
    180          1.7  perseant 	struct buf *bp;
    181          1.7  perseant 	int flags;
    182          1.7  perseant {
    183          1.1   mycroft 	struct lfs *fs;
    184          1.1   mycroft 	struct inode *ip;
    185          1.6      fvdl 	int db, error, s;
    186          1.7  perseant 
    187          1.1   mycroft 	/*
    188          1.1   mycroft 	 * Set the delayed write flag and use reassignbuf to move the buffer
    189          1.1   mycroft 	 * from the clean list to the dirty one.
    190          1.1   mycroft 	 *
    191          1.1   mycroft 	 * Set the B_LOCKED flag and unlock the buffer, causing brelse to move
    192          1.1   mycroft 	 * the buffer onto the LOCKED free list.  This is necessary, otherwise
    193          1.1   mycroft 	 * getnewbuf() would try to reclaim the buffers using bawrite, which
    194          1.1   mycroft 	 * isn't going to work.
    195          1.1   mycroft 	 *
    196          1.1   mycroft 	 * XXX we don't let meta-data writes run out of space because they can
    197          1.1   mycroft 	 * come from the segment writer.  We need to make sure that there is
    198          1.1   mycroft 	 * enough space reserved so that there's room to write meta-data
    199          1.1   mycroft 	 * blocks.
    200          1.1   mycroft 	 */
    201          1.1   mycroft 	if (!(bp->b_flags & B_LOCKED)) {
    202          1.1   mycroft 		fs = VFSTOUFS(bp->b_vp->v_mount)->um_lfs;
    203          1.6      fvdl 		db = fragstodb(fs, numfrags(fs, bp->b_bcount));
    204          1.7  perseant #ifdef DEBUG_LFS
    205          1.7  perseant 		if(CANT_WAIT(bp,flags)) {
    206          1.7  perseant 			if(((db + (fs->lfs_uinodes + INOPB((fs))) / INOPB(fs)
    207          1.7  perseant 			     + fsbtodb(fs, 1)
    208          1.7  perseant 			     + LFS_SUMMARY_SIZE / DEV_BSIZE
    209          1.7  perseant 			     + fs->lfs_segtabsz)) >= fs->lfs_avail)
    210          1.7  perseant 			{
    211          1.7  perseant 				printf("A");
    212          1.7  perseant 			}
    213          1.7  perseant 			if (fs->lfs_nclean <= MIN_FREE_SEGS-1)
    214          1.7  perseant 				printf("M");
    215          1.7  perseant 		}
    216          1.7  perseant #endif
    217          1.7  perseant 		while (!lfs_fits(fs, db) && !CANT_WAIT(bp,flags)) {
    218          1.1   mycroft 			/* Out of space, need cleaner to run */
    219          1.7  perseant 
    220          1.1   mycroft 			wakeup(&lfs_allclean_wakeup);
    221          1.6      fvdl 			wakeup(&fs->lfs_nextseg);
    222          1.7  perseant 			error = tsleep(&fs->lfs_avail, PCATCH | PUSER, "cleaner", NULL);
    223          1.5  christos 			if (error) {
    224          1.7  perseant 				/* printf("lfs_bwrite: error in tsleep"); */
    225          1.1   mycroft 				brelse(bp);
    226          1.1   mycroft 				return (error);
    227          1.1   mycroft 			}
    228          1.1   mycroft 		}
    229          1.7  perseant 
    230          1.7  perseant 		ip = VTOI(bp->b_vp);
    231          1.9  perseant 		if (bp->b_flags & B_CALL)
    232          1.7  perseant 		{
    233          1.7  perseant 			if(!(ip->i_flag & IN_CLEANING))
    234          1.7  perseant 				++fs->lfs_uinodes;
    235          1.7  perseant 			ip->i_flag |= IN_CLEANING;
    236          1.7  perseant 		} else {
    237          1.7  perseant 			if(!(ip->i_flag & IN_MODIFIED))
    238          1.7  perseant 				++fs->lfs_uinodes;
    239          1.7  perseant 			ip->i_flag |= IN_CHANGE | IN_MODIFIED | IN_UPDATE;
    240          1.7  perseant 		}
    241          1.6      fvdl 		fs->lfs_avail -= db;
    242          1.1   mycroft 		++locked_queue_count;
    243          1.7  perseant 		locked_queue_bytes += bp->b_bufsize;
    244          1.7  perseant #ifdef LFS_HONOR_RDONLY
    245          1.7  perseant 		/*
    246          1.7  perseant 		 * XXX KS - Don't write blocks if we're mounted ro.
    247          1.7  perseant 		 * Placement here means that the cleaner can't write
    248          1.7  perseant 		 * blocks either.
    249          1.7  perseant 		 */
    250          1.7  perseant 	        if(VTOI(bp->b_vp)->i_lfs->lfs_ronly)
    251          1.7  perseant 			bp->b_flags &= ~(B_DELWRI|B_LOCKED);
    252          1.7  perseant 		else
    253          1.7  perseant #endif
    254          1.7  perseant 			bp->b_flags |= B_DELWRI | B_LOCKED;
    255          1.1   mycroft 		bp->b_flags &= ~(B_READ | B_ERROR);
    256          1.1   mycroft 		s = splbio();
    257          1.1   mycroft 		reassignbuf(bp, bp->b_vp);
    258          1.1   mycroft 		splx(s);
    259          1.9  perseant 
    260          1.1   mycroft 	}
    261          1.7  perseant 
    262          1.9  perseant 	if(bp->b_flags & B_CALL)
    263          1.7  perseant 		bp->b_flags &= ~B_BUSY;
    264          1.7  perseant 	else
    265          1.7  perseant 		brelse(bp);
    266          1.7  perseant 
    267          1.1   mycroft 	return (0);
    268          1.1   mycroft }
    269          1.1   mycroft 
    270  1.9.2.1.2.1   thorpej void lfs_flush_fs(mp, flags)
    271  1.9.2.1.2.1   thorpej 	struct mount *mp;
    272  1.9.2.1.2.1   thorpej 	int flags;
    273  1.9.2.1.2.1   thorpej {
    274  1.9.2.1.2.1   thorpej 	struct lfs *lfsp;
    275  1.9.2.1.2.1   thorpej 
    276  1.9.2.1.2.1   thorpej 	lfsp = ((struct ufsmount *)mp->mnt_data)->ufsmount_u.lfs;
    277  1.9.2.1.2.1   thorpej 	if((mp->mnt_flag & MNT_RDONLY) == 0 &&
    278  1.9.2.1.2.1   thorpej 	   lfsp->lfs_dirops==0)
    279  1.9.2.1.2.1   thorpej 	{
    280  1.9.2.1.2.1   thorpej 		/* disallow dirops during flush */
    281  1.9.2.1.2.1   thorpej 		lfsp->lfs_writer++;
    282  1.9.2.1.2.1   thorpej 
    283  1.9.2.1.2.1   thorpej 		/*
    284  1.9.2.1.2.1   thorpej 		 * We set the queue to 0 here because we
    285  1.9.2.1.2.1   thorpej 		 * are about to write all the dirty
    286  1.9.2.1.2.1   thorpej 		 * buffers we have.  If more come in
    287  1.9.2.1.2.1   thorpej 		 * while we're writing the segment, they
    288  1.9.2.1.2.1   thorpej 		 * may not get written, so we want the
    289  1.9.2.1.2.1   thorpej 		 * count to reflect these new writes
    290  1.9.2.1.2.1   thorpej 		 * after the segwrite completes.
    291  1.9.2.1.2.1   thorpej 		 */
    292  1.9.2.1.2.1   thorpej 		if(lfs_dostats)
    293  1.9.2.1.2.1   thorpej 			++lfs_stats.flush_invoked;
    294  1.9.2.1.2.1   thorpej 		lfs_segwrite(mp, flags);
    295  1.9.2.1.2.1   thorpej 
    296  1.9.2.1.2.1   thorpej 		/* XXX KS - allow dirops again */
    297  1.9.2.1.2.1   thorpej 		if(--lfsp->lfs_writer==0)
    298  1.9.2.1.2.1   thorpej 			wakeup(&lfsp->lfs_dirops);
    299  1.9.2.1.2.1   thorpej 	}
    300  1.9.2.1.2.1   thorpej }
    301  1.9.2.1.2.1   thorpej 
    302          1.1   mycroft /*
    303          1.1   mycroft  * XXX
    304          1.1   mycroft  * This routine flushes buffers out of the B_LOCKED queue when LFS has too
    305          1.1   mycroft  * many locked down.  Eventually the pageout daemon will simply call LFS
    306          1.1   mycroft  * when pages need to be reclaimed.  Note, we have one static count of locked
    307          1.1   mycroft  * buffers, so we can't have more than a single file system.  To make this
    308          1.1   mycroft  * work for multiple file systems, put the count into the mount structure.
    309          1.1   mycroft  */
    310          1.1   mycroft void
    311          1.7  perseant lfs_flush(fs, flags)
    312          1.7  perseant 	struct lfs *fs;
    313          1.7  perseant 	int flags;
    314          1.1   mycroft {
    315          1.6      fvdl 	register struct mount *mp, *nmp;
    316          1.7  perseant 
    317          1.7  perseant 	if(lfs_dostats)
    318          1.7  perseant 		++lfs_stats.write_exceeded;
    319          1.7  perseant 	if (lfs_writing && flags==0) /* XXX flags */
    320          1.1   mycroft 		return;
    321          1.1   mycroft 	lfs_writing = 1;
    322          1.7  perseant 
    323          1.6      fvdl 	simple_lock(&mountlist_slock);
    324          1.6      fvdl 	for (mp = mountlist.cqh_first; mp != (void *)&mountlist; mp = nmp) {
    325          1.6      fvdl 		if (vfs_busy(mp, LK_NOWAIT, &mountlist_slock)) {
    326          1.6      fvdl 			nmp = mp->mnt_list.cqe_next;
    327          1.6      fvdl 			continue;
    328          1.6      fvdl 		}
    329          1.7  perseant 		if (strncmp(&mp->mnt_stat.f_fstypename[0], MOUNT_LFS, MFSNAMELEN)==0)
    330  1.9.2.1.2.1   thorpej 			lfs_flush_fs(mp, flags);
    331          1.6      fvdl 		simple_lock(&mountlist_slock);
    332          1.6      fvdl 		nmp = mp->mnt_list.cqe_next;
    333          1.6      fvdl 		vfs_unbusy(mp);
    334          1.1   mycroft 	}
    335          1.6      fvdl 	simple_unlock(&mountlist_slock);
    336          1.7  perseant 
    337          1.7  perseant 	lfs_countlocked(&locked_queue_count,&locked_queue_bytes);
    338          1.7  perseant 	wakeup(&locked_queue_count);
    339          1.7  perseant 
    340          1.1   mycroft 	lfs_writing = 0;
    341          1.1   mycroft }
    342          1.1   mycroft 
    343          1.1   mycroft int
    344          1.7  perseant lfs_check(vp, blkno, flags)
    345          1.1   mycroft 	struct vnode *vp;
    346          1.6      fvdl 	ufs_daddr_t blkno;
    347          1.7  perseant 	int flags;
    348          1.1   mycroft {
    349          1.1   mycroft 	int error;
    350      1.9.2.1  perseant 	struct lfs *fs;
    351      1.9.2.1  perseant 
    352          1.1   mycroft 	error = 0;
    353          1.1   mycroft 	if (incore(vp, blkno))
    354          1.1   mycroft 		return (0);
    355          1.7  perseant 
    356          1.7  perseant 	/* If out of buffers, wait on writer */
    357          1.7  perseant 	/* XXX KS - if it's the Ifile, we're probably the cleaner! */
    358          1.7  perseant 	if (VTOI(vp)->i_number == LFS_IFILE_INUM)
    359          1.7  perseant 		return 0;
    360          1.7  perseant 
    361      1.9.2.1  perseant 	/* If dirops are active, can't flush.  Wait for SET_ENDOP */
    362      1.9.2.1  perseant 	fs = VTOI(vp)->i_lfs;
    363      1.9.2.1  perseant 	if (fs->lfs_dirops)
    364      1.9.2.1  perseant 		return 0;
    365      1.9.2.1  perseant 
    366          1.7  perseant 	if (locked_queue_count > LFS_MAX_BUFS
    367      1.9.2.1  perseant 	    || locked_queue_bytes > LFS_MAX_BYTES
    368  1.9.2.1.2.1   thorpej 	    || fs->lfs_dirvcount > LFS_MAXDIROP
    369  1.9.2.1.2.1   thorpej 	    || fs->lfs_diropwait > 0)
    370          1.7  perseant 	{
    371      1.9.2.1  perseant 		++fs->lfs_writer;
    372      1.9.2.1  perseant 		lfs_flush(fs, flags);
    373      1.9.2.1  perseant 		if(--fs->lfs_writer==0)
    374      1.9.2.1  perseant 			wakeup(&fs->lfs_dirops);
    375          1.7  perseant 	}
    376  1.9.2.1.2.1   thorpej 
    377          1.7  perseant 	while  (locked_queue_count > LFS_WAIT_BUFS
    378          1.7  perseant 		|| locked_queue_bytes > LFS_WAIT_BYTES)
    379          1.7  perseant 	{
    380          1.7  perseant 		if(lfs_dostats)
    381          1.7  perseant 			++lfs_stats.wait_exceeded;
    382          1.7  perseant 		error = tsleep(&locked_queue_count, PCATCH | PUSER,
    383          1.7  perseant 			       "buffers", hz * LFS_BUFWAIT);
    384          1.7  perseant 	}
    385          1.7  perseant 	return (error);
    386          1.7  perseant }
    387          1.1   mycroft 
    388          1.7  perseant /*
    389          1.7  perseant  * Allocate a new buffer header.
    390          1.7  perseant  */
    391          1.7  perseant struct buf *
    392          1.7  perseant lfs_newbuf(vp, daddr, size)
    393          1.7  perseant 	struct vnode *vp;
    394          1.7  perseant 	ufs_daddr_t daddr;
    395          1.7  perseant 	size_t size;
    396          1.7  perseant {
    397          1.7  perseant 	struct buf *bp;
    398          1.7  perseant 	size_t nbytes;
    399          1.7  perseant 	int s;
    400          1.7  perseant 
    401          1.7  perseant 	nbytes = roundup(size, DEV_BSIZE);
    402          1.7  perseant 
    403          1.7  perseant 	bp = malloc(sizeof(struct buf), M_SEGMENT, M_WAITOK);
    404          1.7  perseant 	bzero(bp, sizeof(struct buf));
    405          1.7  perseant 	if (nbytes)
    406          1.7  perseant 		bp->b_data = malloc(nbytes, M_SEGMENT, M_WAITOK);
    407          1.7  perseant 	if(nbytes) {
    408          1.7  perseant 		bzero(bp->b_data, nbytes);
    409          1.7  perseant 	}
    410          1.7  perseant #ifdef DIAGNOSTIC
    411          1.7  perseant 	if(vp==NULL)
    412          1.7  perseant 		panic("vp is NULL in lfs_newbuf");
    413          1.7  perseant 	if(bp==NULL)
    414          1.7  perseant 		panic("bp is NULL after malloc in lfs_newbuf");
    415          1.1   mycroft #endif
    416          1.7  perseant 	s = splbio();
    417          1.7  perseant 	bgetvp(vp, bp);
    418          1.7  perseant 	splx(s);
    419          1.7  perseant 
    420          1.7  perseant 	bp->b_bufsize = size;
    421          1.7  perseant 	bp->b_bcount = size;
    422          1.7  perseant 	bp->b_lblkno = daddr;
    423          1.7  perseant 	bp->b_blkno = daddr;
    424          1.7  perseant 	bp->b_error = 0;
    425          1.7  perseant 	bp->b_resid = 0;
    426          1.7  perseant 	bp->b_iodone = lfs_callback;
    427          1.7  perseant 	bp->b_flags |= B_BUSY | B_CALL | B_NOCACHE;
    428          1.7  perseant 
    429          1.7  perseant 	return (bp);
    430          1.7  perseant }
    431          1.7  perseant 
    432          1.7  perseant void
    433          1.7  perseant lfs_freebuf(bp)
    434          1.7  perseant 	struct buf *bp;
    435          1.7  perseant {
    436          1.7  perseant 	int s;
    437          1.7  perseant 
    438          1.7  perseant 	s = splbio();
    439          1.7  perseant 	if(bp->b_vp)
    440          1.7  perseant 		brelvp(bp);
    441          1.7  perseant 	splx(s);
    442          1.7  perseant 	if (!(bp->b_flags & B_INVAL)) { /* B_INVAL indicates a "fake" buffer */
    443          1.7  perseant 		free(bp->b_data, M_SEGMENT);
    444          1.7  perseant 		bp->b_data = NULL;
    445          1.1   mycroft 	}
    446          1.7  perseant 	free(bp, M_SEGMENT);
    447          1.7  perseant }
    448          1.1   mycroft 
    449          1.7  perseant /*
    450          1.7  perseant  * Definitions for the buffer free lists.
    451          1.7  perseant  */
    452          1.7  perseant #define BQUEUES		4		/* number of free buffer queues */
    453          1.7  perseant 
    454          1.7  perseant #define BQ_LOCKED	0		/* super-blocks &c */
    455          1.7  perseant #define BQ_LRU		1		/* lru, useful buffers */
    456          1.7  perseant #define BQ_AGE		2		/* rubbish */
    457          1.7  perseant #define BQ_EMPTY	3		/* buffer headers with no memory */
    458          1.7  perseant 
    459          1.7  perseant extern TAILQ_HEAD(bqueues, buf) bufqueues[BQUEUES];
    460          1.7  perseant 
    461          1.7  perseant /*
    462          1.7  perseant  * Return a count of buffers on the "locked" queue.
    463          1.7  perseant  */
    464          1.7  perseant void
    465          1.7  perseant lfs_countlocked(count, bytes)
    466          1.7  perseant 	int *count;
    467          1.7  perseant 	long *bytes;
    468          1.7  perseant {
    469          1.7  perseant 	register struct buf *bp;
    470          1.7  perseant 	register int n = 0;
    471          1.7  perseant 	register long int size = 0L;
    472          1.7  perseant 
    473          1.7  perseant 	for (bp = bufqueues[BQ_LOCKED].tqh_first; bp;
    474          1.7  perseant 	    bp = bp->b_freelist.tqe_next) {
    475          1.7  perseant 		n++;
    476          1.7  perseant 		size += bp->b_bufsize;
    477          1.7  perseant 	}
    478          1.7  perseant 	*count = n;
    479          1.7  perseant 	*bytes = size;
    480          1.7  perseant 	return;
    481          1.1   mycroft }
    482