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ffs_inode.c revision 1.26
      1  1.26   mycroft /*	$NetBSD: ffs_inode.c,v 1.26 1999/03/05 20:47:07 mycroft Exp $	*/
      2   1.5       cgd 
      3   1.1   mycroft /*
      4   1.1   mycroft  * Copyright (c) 1982, 1986, 1989, 1993
      5   1.1   mycroft  *	The Regents of the University of California.  All rights reserved.
      6   1.1   mycroft  *
      7   1.1   mycroft  * Redistribution and use in source and binary forms, with or without
      8   1.1   mycroft  * modification, are permitted provided that the following conditions
      9   1.1   mycroft  * are met:
     10   1.1   mycroft  * 1. Redistributions of source code must retain the above copyright
     11   1.1   mycroft  *    notice, this list of conditions and the following disclaimer.
     12   1.1   mycroft  * 2. Redistributions in binary form must reproduce the above copyright
     13   1.1   mycroft  *    notice, this list of conditions and the following disclaimer in the
     14   1.1   mycroft  *    documentation and/or other materials provided with the distribution.
     15   1.1   mycroft  * 3. All advertising materials mentioning features or use of this software
     16   1.1   mycroft  *    must display the following acknowledgement:
     17   1.1   mycroft  *	This product includes software developed by the University of
     18   1.1   mycroft  *	California, Berkeley and its contributors.
     19   1.1   mycroft  * 4. Neither the name of the University nor the names of its contributors
     20   1.1   mycroft  *    may be used to endorse or promote products derived from this software
     21   1.1   mycroft  *    without specific prior written permission.
     22   1.1   mycroft  *
     23   1.1   mycroft  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24   1.1   mycroft  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25   1.1   mycroft  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26   1.1   mycroft  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27   1.1   mycroft  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28   1.1   mycroft  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29   1.1   mycroft  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30   1.1   mycroft  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31   1.1   mycroft  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32   1.1   mycroft  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33   1.1   mycroft  * SUCH DAMAGE.
     34   1.1   mycroft  *
     35  1.18      fvdl  *	@(#)ffs_inode.c	8.13 (Berkeley) 4/21/95
     36   1.1   mycroft  */
     37  1.17       mrg 
     38  1.21    scottr #if defined(_KERNEL) && !defined(_LKM)
     39  1.25   thorpej #include "opt_ffs.h"
     40  1.20    scottr #include "opt_quota.h"
     41  1.17       mrg #include "opt_uvm.h"
     42  1.21    scottr #endif
     43   1.1   mycroft 
     44   1.1   mycroft #include <sys/param.h>
     45   1.1   mycroft #include <sys/systm.h>
     46   1.1   mycroft #include <sys/mount.h>
     47   1.1   mycroft #include <sys/proc.h>
     48   1.1   mycroft #include <sys/file.h>
     49   1.1   mycroft #include <sys/buf.h>
     50   1.1   mycroft #include <sys/vnode.h>
     51   1.1   mycroft #include <sys/kernel.h>
     52   1.1   mycroft #include <sys/malloc.h>
     53   1.1   mycroft #include <sys/trace.h>
     54   1.1   mycroft #include <sys/resourcevar.h>
     55   1.1   mycroft 
     56   1.1   mycroft #include <vm/vm.h>
     57   1.1   mycroft 
     58  1.16       mrg #if defined(UVM)
     59  1.16       mrg #include <uvm/uvm_extern.h>
     60  1.16       mrg #endif
     61  1.16       mrg 
     62   1.1   mycroft #include <ufs/ufs/quota.h>
     63   1.1   mycroft #include <ufs/ufs/inode.h>
     64   1.1   mycroft #include <ufs/ufs/ufsmount.h>
     65   1.1   mycroft #include <ufs/ufs/ufs_extern.h>
     66  1.19    bouyer #include <ufs/ufs/ufs_bswap.h>
     67   1.1   mycroft 
     68   1.1   mycroft #include <ufs/ffs/fs.h>
     69   1.1   mycroft #include <ufs/ffs/ffs_extern.h>
     70   1.1   mycroft 
     71  1.18      fvdl static int ffs_indirtrunc __P((struct inode *, ufs_daddr_t, ufs_daddr_t,
     72  1.18      fvdl 			       ufs_daddr_t, int, long *));
     73   1.1   mycroft 
     74   1.1   mycroft /*
     75  1.13       tls  * Update the access, modified, and inode change times as specified
     76  1.13       tls  * by the IN_ACCESS, IN_UPDATE, and IN_CHANGE flags respectively.
     77  1.13       tls  * The IN_MODIFIED flag is used to specify that the inode needs to be
     78  1.13       tls  * updated but that the times have already been set. The access
     79  1.13       tls  * and modified times are taken from the second and third parameters;
     80  1.13       tls  * the inode change time is always taken from the current time. If
     81  1.13       tls  * waitfor is set, then wait for the disk write of the inode to
     82   1.1   mycroft  * complete.
     83   1.1   mycroft  */
     84  1.13       tls 
     85   1.1   mycroft int
     86   1.9  christos ffs_update(v)
     87   1.9  christos 	void *v;
     88   1.9  christos {
     89   1.1   mycroft 	struct vop_update_args /* {
     90   1.1   mycroft 		struct vnode *a_vp;
     91  1.10   mycroft 		struct timespec *a_access;
     92  1.10   mycroft 		struct timespec *a_modify;
     93   1.1   mycroft 		int a_waitfor;
     94   1.9  christos 	} */ *ap = v;
     95   1.1   mycroft 	register struct fs *fs;
     96   1.1   mycroft 	struct buf *bp;
     97   1.1   mycroft 	struct inode *ip;
     98   1.1   mycroft 	int error;
     99  1.11   mycroft 	struct timespec ts;
    100  1.24   thorpej 	caddr_t cp;
    101   1.1   mycroft 
    102  1.11   mycroft 	if (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY)
    103  1.11   mycroft 		return (0);
    104   1.1   mycroft 	ip = VTOI(ap->a_vp);
    105  1.11   mycroft 	TIMEVAL_TO_TIMESPEC(&time, &ts);
    106  1.26   mycroft 	FFS_ITIMES(ip,
    107  1.26   mycroft 	    ap->a_access ? ap->a_access : &ts,
    108  1.26   mycroft 	    ap->a_modify ? ap->a_modify : &ts, &ts);
    109  1.11   mycroft 	if ((ip->i_flag & IN_MODIFIED) == 0)
    110   1.1   mycroft 		return (0);
    111  1.11   mycroft 	ip->i_flag &= ~IN_MODIFIED;
    112   1.1   mycroft 	fs = ip->i_fs;
    113   1.1   mycroft 	/*
    114   1.1   mycroft 	 * Ensure that uid and gid are correct. This is a temporary
    115   1.1   mycroft 	 * fix until fsck has been changed to do the update.
    116   1.1   mycroft 	 */
    117  1.18      fvdl 	if (fs->fs_inodefmt < FS_44INODEFMT) {			/* XXX */
    118  1.18      fvdl 		ip->i_din.ffs_din.di_ouid = ip->i_ffs_uid;	/* XXX */
    119  1.18      fvdl 		ip->i_din.ffs_din.di_ogid = ip->i_ffs_gid;	/* XXX */
    120  1.18      fvdl 	}							/* XXX */
    121   1.9  christos 	error = bread(ip->i_devvp,
    122   1.9  christos 		      fsbtodb(fs, ino_to_fsba(fs, ip->i_number)),
    123   1.9  christos 		      (int)fs->fs_bsize, NOCRED, &bp);
    124   1.9  christos 	if (error) {
    125   1.1   mycroft 		brelse(bp);
    126   1.1   mycroft 		return (error);
    127   1.1   mycroft 	}
    128  1.24   thorpej 	cp = (caddr_t)bp->b_data +
    129  1.24   thorpej 	    (ino_to_fsbo(fs, ip->i_number) * DINODE_SIZE);
    130  1.23  christos #ifdef FFS_EI
    131  1.19    bouyer 	if (UFS_MPNEEDSWAP(ap->a_vp->v_mount))
    132  1.24   thorpej 		ffs_dinode_swap(&ip->i_din.ffs_din, (struct dinode *)cp);
    133  1.19    bouyer 	else
    134  1.23  christos #endif
    135  1.24   thorpej 		memcpy(cp, &ip->i_din.ffs_din, DINODE_SIZE);
    136  1.18      fvdl 	if (ap->a_waitfor && (ap->a_vp->v_mount->mnt_flag & MNT_ASYNC) == 0)
    137   1.1   mycroft 		return (bwrite(bp));
    138   1.1   mycroft 	else {
    139   1.1   mycroft 		bdwrite(bp);
    140   1.1   mycroft 		return (0);
    141   1.1   mycroft 	}
    142   1.1   mycroft }
    143   1.1   mycroft 
    144   1.1   mycroft #define	SINGLE	0	/* index of single indirect block */
    145   1.1   mycroft #define	DOUBLE	1	/* index of double indirect block */
    146   1.1   mycroft #define	TRIPLE	2	/* index of triple indirect block */
    147   1.1   mycroft /*
    148   1.1   mycroft  * Truncate the inode oip to at most length size, freeing the
    149   1.1   mycroft  * disk blocks.
    150   1.1   mycroft  */
    151   1.9  christos int
    152   1.9  christos ffs_truncate(v)
    153   1.9  christos 	void *v;
    154   1.9  christos {
    155   1.1   mycroft 	struct vop_truncate_args /* {
    156   1.1   mycroft 		struct vnode *a_vp;
    157   1.1   mycroft 		off_t a_length;
    158   1.1   mycroft 		int a_flags;
    159   1.1   mycroft 		struct ucred *a_cred;
    160   1.1   mycroft 		struct proc *a_p;
    161   1.9  christos 	} */ *ap = v;
    162   1.1   mycroft 	register struct vnode *ovp = ap->a_vp;
    163  1.18      fvdl 	register ufs_daddr_t lastblock;
    164   1.1   mycroft 	register struct inode *oip;
    165  1.18      fvdl 	ufs_daddr_t bn, lbn, lastiblock[NIADDR], indir_lbn[NIADDR];
    166  1.18      fvdl 	ufs_daddr_t oldblks[NDADDR + NIADDR], newblks[NDADDR + NIADDR];
    167   1.1   mycroft 	off_t length = ap->a_length;
    168   1.1   mycroft 	register struct fs *fs;
    169   1.1   mycroft 	struct buf *bp;
    170   1.1   mycroft 	int offset, size, level;
    171   1.1   mycroft 	long count, nblocks, vflags, blocksreleased = 0;
    172  1.10   mycroft 	struct timespec ts;
    173   1.1   mycroft 	register int i;
    174   1.1   mycroft 	int aflags, error, allerror;
    175   1.1   mycroft 	off_t osize;
    176   1.1   mycroft 
    177   1.2        pk 	if (length < 0)
    178   1.3   mycroft 		return (EINVAL);
    179   1.1   mycroft 	oip = VTOI(ovp);
    180  1.10   mycroft 	TIMEVAL_TO_TIMESPEC(&time, &ts);
    181   1.1   mycroft 	if (ovp->v_type == VLNK &&
    182  1.14    bouyer 	    (oip->i_ffs_size < ovp->v_mount->mnt_maxsymlinklen ||
    183   1.4   mycroft 	     (ovp->v_mount->mnt_maxsymlinklen == 0 &&
    184  1.14    bouyer 	      oip->i_din.ffs_din.di_blocks == 0))) {
    185   1.1   mycroft #ifdef DIAGNOSTIC
    186   1.1   mycroft 		if (length != 0)
    187   1.1   mycroft 			panic("ffs_truncate: partial truncate of symlink");
    188   1.1   mycroft #endif
    189  1.22     perry 		memset((char *)&oip->i_ffs_shortlink, 0, (u_int)oip->i_ffs_size);
    190  1.14    bouyer 		oip->i_ffs_size = 0;
    191   1.1   mycroft 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
    192  1.10   mycroft 		return (VOP_UPDATE(ovp, &ts, &ts, 1));
    193   1.1   mycroft 	}
    194  1.14    bouyer 	if (oip->i_ffs_size == length) {
    195   1.1   mycroft 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
    196  1.10   mycroft 		return (VOP_UPDATE(ovp, &ts, &ts, 0));
    197   1.1   mycroft 	}
    198   1.1   mycroft #ifdef QUOTA
    199   1.9  christos 	if ((error = getinoquota(oip)) != 0)
    200   1.1   mycroft 		return (error);
    201   1.1   mycroft #endif
    202   1.1   mycroft 	fs = oip->i_fs;
    203  1.14    bouyer 	osize = oip->i_ffs_size;
    204  1.18      fvdl 	ovp->v_lasta = ovp->v_clen = ovp->v_cstart = ovp->v_lastw = 0;
    205   1.1   mycroft 	/*
    206   1.1   mycroft 	 * Lengthen the size of the file. We must ensure that the
    207   1.1   mycroft 	 * last byte of the file is allocated. Since the smallest
    208   1.6   mycroft 	 * value of osize is 0, length will be at least 1.
    209   1.1   mycroft 	 */
    210   1.1   mycroft 	if (osize < length) {
    211   1.6   mycroft 		if (length > fs->fs_maxfilesize)
    212   1.6   mycroft 			return (EFBIG);
    213   1.1   mycroft 		offset = blkoff(fs, length - 1);
    214   1.1   mycroft 		lbn = lblkno(fs, length - 1);
    215   1.1   mycroft 		aflags = B_CLRBUF;
    216   1.1   mycroft 		if (ap->a_flags & IO_SYNC)
    217   1.1   mycroft 			aflags |= B_SYNC;
    218   1.9  christos 		error = ffs_balloc(oip, lbn, offset + 1, ap->a_cred, &bp,
    219   1.9  christos 				   aflags);
    220   1.9  christos 		if (error)
    221   1.1   mycroft 			return (error);
    222  1.14    bouyer 		oip->i_ffs_size = length;
    223  1.16       mrg #if defined(UVM)
    224  1.18      fvdl 		uvm_vnp_setsize(ovp, length);
    225  1.16       mrg 		(void) uvm_vnp_uncache(ovp);
    226  1.16       mrg #else
    227  1.18      fvdl 		vnode_pager_setsize(ovp, length);
    228   1.1   mycroft 		(void) vnode_pager_uncache(ovp);
    229  1.16       mrg #endif
    230   1.1   mycroft 		if (aflags & B_SYNC)
    231   1.1   mycroft 			bwrite(bp);
    232   1.1   mycroft 		else
    233   1.1   mycroft 			bawrite(bp);
    234   1.1   mycroft 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
    235  1.10   mycroft 		return (VOP_UPDATE(ovp, &ts, &ts, 1));
    236   1.1   mycroft 	}
    237   1.1   mycroft 	/*
    238   1.1   mycroft 	 * Shorten the size of the file. If the file is not being
    239   1.1   mycroft 	 * truncated to a block boundry, the contents of the
    240   1.1   mycroft 	 * partial block following the end of the file must be
    241   1.1   mycroft 	 * zero'ed in case it ever become accessable again because
    242   1.1   mycroft 	 * of subsequent file growth.
    243   1.1   mycroft 	 */
    244   1.1   mycroft 	offset = blkoff(fs, length);
    245   1.1   mycroft 	if (offset == 0) {
    246  1.14    bouyer 		oip->i_ffs_size = length;
    247   1.1   mycroft 	} else {
    248   1.1   mycroft 		lbn = lblkno(fs, length);
    249   1.1   mycroft 		aflags = B_CLRBUF;
    250   1.1   mycroft 		if (ap->a_flags & IO_SYNC)
    251   1.1   mycroft 			aflags |= B_SYNC;
    252   1.9  christos 		error = ffs_balloc(oip, lbn, offset, ap->a_cred, &bp, aflags);
    253   1.9  christos 		if (error)
    254   1.1   mycroft 			return (error);
    255  1.14    bouyer 		oip->i_ffs_size = length;
    256   1.1   mycroft 		size = blksize(fs, oip, lbn);
    257  1.16       mrg #if defined(UVM)
    258  1.16       mrg 		(void) uvm_vnp_uncache(ovp);
    259  1.16       mrg #else
    260   1.1   mycroft 		(void) vnode_pager_uncache(ovp);
    261  1.16       mrg #endif
    262  1.22     perry 		memset((char *)bp->b_data + offset, 0,  (u_int)(size - offset));
    263   1.1   mycroft 		allocbuf(bp, size);
    264   1.1   mycroft 		if (aflags & B_SYNC)
    265   1.1   mycroft 			bwrite(bp);
    266   1.1   mycroft 		else
    267   1.1   mycroft 			bawrite(bp);
    268   1.1   mycroft 	}
    269  1.18      fvdl #if defined(UVM)
    270  1.18      fvdl 	uvm_vnp_setsize(ovp, length);
    271  1.18      fvdl #else
    272  1.18      fvdl 	vnode_pager_setsize(ovp, length);
    273  1.18      fvdl #endif
    274   1.1   mycroft 	/*
    275   1.1   mycroft 	 * Calculate index into inode's block list of
    276   1.1   mycroft 	 * last direct and indirect blocks (if any)
    277   1.1   mycroft 	 * which we want to keep.  Lastblock is -1 when
    278   1.1   mycroft 	 * the file is truncated to 0.
    279   1.1   mycroft 	 */
    280   1.1   mycroft 	lastblock = lblkno(fs, length + fs->fs_bsize - 1) - 1;
    281   1.1   mycroft 	lastiblock[SINGLE] = lastblock - NDADDR;
    282   1.1   mycroft 	lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
    283   1.1   mycroft 	lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
    284   1.1   mycroft 	nblocks = btodb(fs->fs_bsize);
    285   1.1   mycroft 	/*
    286   1.1   mycroft 	 * Update file and block pointers on disk before we start freeing
    287   1.1   mycroft 	 * blocks.  If we crash before free'ing blocks below, the blocks
    288   1.1   mycroft 	 * will be returned to the free list.  lastiblock values are also
    289   1.1   mycroft 	 * normalized to -1 for calls to ffs_indirtrunc below.
    290   1.1   mycroft 	 */
    291  1.22     perry 	memcpy((caddr_t)oldblks, (caddr_t)&oip->i_ffs_db[0], sizeof oldblks);
    292   1.1   mycroft 	for (level = TRIPLE; level >= SINGLE; level--)
    293   1.1   mycroft 		if (lastiblock[level] < 0) {
    294  1.14    bouyer 			oip->i_ffs_ib[level] = 0;
    295   1.1   mycroft 			lastiblock[level] = -1;
    296   1.1   mycroft 		}
    297   1.1   mycroft 	for (i = NDADDR - 1; i > lastblock; i--)
    298  1.14    bouyer 		oip->i_ffs_db[i] = 0;
    299   1.1   mycroft 	oip->i_flag |= IN_CHANGE | IN_UPDATE;
    300  1.10   mycroft 	if ((error = VOP_UPDATE(ovp, &ts, &ts, 1)) != 0)
    301   1.1   mycroft 		allerror = error;
    302   1.1   mycroft 	/*
    303   1.1   mycroft 	 * Having written the new inode to disk, save its new configuration
    304   1.1   mycroft 	 * and put back the old block pointers long enough to process them.
    305   1.1   mycroft 	 * Note that we save the new block configuration so we can check it
    306   1.1   mycroft 	 * when we are done.
    307   1.1   mycroft 	 */
    308  1.22     perry 	memcpy((caddr_t)newblks, (caddr_t)&oip->i_ffs_db[0], sizeof newblks);
    309  1.22     perry 	memcpy((caddr_t)&oip->i_ffs_db[0], (caddr_t)oldblks, sizeof oldblks);
    310  1.14    bouyer 	oip->i_ffs_size = osize;
    311   1.1   mycroft 	vflags = ((length > 0) ? V_SAVE : 0) | V_SAVEMETA;
    312   1.1   mycroft 	allerror = vinvalbuf(ovp, vflags, ap->a_cred, ap->a_p, 0, 0);
    313   1.1   mycroft 
    314   1.1   mycroft 	/*
    315   1.1   mycroft 	 * Indirect blocks first.
    316   1.1   mycroft 	 */
    317   1.1   mycroft 	indir_lbn[SINGLE] = -NDADDR;
    318   1.1   mycroft 	indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) - 1;
    319   1.1   mycroft 	indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1;
    320   1.1   mycroft 	for (level = TRIPLE; level >= SINGLE; level--) {
    321  1.19    bouyer 		bn = ufs_rw32(oip->i_ffs_ib[level], UFS_MPNEEDSWAP(ovp->v_mount));
    322   1.1   mycroft 		if (bn != 0) {
    323   1.1   mycroft 			error = ffs_indirtrunc(oip, indir_lbn[level],
    324   1.1   mycroft 			    fsbtodb(fs, bn), lastiblock[level], level, &count);
    325   1.1   mycroft 			if (error)
    326   1.1   mycroft 				allerror = error;
    327   1.1   mycroft 			blocksreleased += count;
    328   1.1   mycroft 			if (lastiblock[level] < 0) {
    329  1.14    bouyer 				oip->i_ffs_ib[level] = 0;
    330   1.1   mycroft 				ffs_blkfree(oip, bn, fs->fs_bsize);
    331   1.1   mycroft 				blocksreleased += nblocks;
    332   1.1   mycroft 			}
    333   1.1   mycroft 		}
    334   1.1   mycroft 		if (lastiblock[level] >= 0)
    335   1.1   mycroft 			goto done;
    336   1.1   mycroft 	}
    337   1.1   mycroft 
    338   1.1   mycroft 	/*
    339   1.1   mycroft 	 * All whole direct blocks or frags.
    340   1.1   mycroft 	 */
    341   1.1   mycroft 	for (i = NDADDR - 1; i > lastblock; i--) {
    342   1.1   mycroft 		register long bsize;
    343   1.1   mycroft 
    344  1.19    bouyer 		bn = ufs_rw32(oip->i_ffs_db[i], UFS_MPNEEDSWAP(ovp->v_mount));
    345   1.1   mycroft 		if (bn == 0)
    346   1.1   mycroft 			continue;
    347  1.14    bouyer 		oip->i_ffs_db[i] = 0;
    348   1.1   mycroft 		bsize = blksize(fs, oip, i);
    349   1.1   mycroft 		ffs_blkfree(oip, bn, bsize);
    350   1.1   mycroft 		blocksreleased += btodb(bsize);
    351   1.1   mycroft 	}
    352   1.1   mycroft 	if (lastblock < 0)
    353   1.1   mycroft 		goto done;
    354   1.1   mycroft 
    355   1.1   mycroft 	/*
    356   1.1   mycroft 	 * Finally, look for a change in size of the
    357   1.1   mycroft 	 * last direct block; release any frags.
    358   1.1   mycroft 	 */
    359  1.19    bouyer 	bn = ufs_rw32(oip->i_ffs_db[lastblock], UFS_MPNEEDSWAP(ovp->v_mount));
    360   1.1   mycroft 	if (bn != 0) {
    361   1.1   mycroft 		long oldspace, newspace;
    362   1.1   mycroft 
    363   1.1   mycroft 		/*
    364   1.1   mycroft 		 * Calculate amount of space we're giving
    365   1.1   mycroft 		 * back as old block size minus new block size.
    366   1.1   mycroft 		 */
    367   1.1   mycroft 		oldspace = blksize(fs, oip, lastblock);
    368  1.14    bouyer 		oip->i_ffs_size = length;
    369   1.1   mycroft 		newspace = blksize(fs, oip, lastblock);
    370   1.1   mycroft 		if (newspace == 0)
    371   1.1   mycroft 			panic("itrunc: newspace");
    372   1.1   mycroft 		if (oldspace - newspace > 0) {
    373   1.1   mycroft 			/*
    374   1.1   mycroft 			 * Block number of space to be free'd is
    375   1.1   mycroft 			 * the old block # plus the number of frags
    376   1.1   mycroft 			 * required for the storage we're keeping.
    377   1.1   mycroft 			 */
    378   1.1   mycroft 			bn += numfrags(fs, newspace);
    379   1.1   mycroft 			ffs_blkfree(oip, bn, oldspace - newspace);
    380   1.1   mycroft 			blocksreleased += btodb(oldspace - newspace);
    381   1.1   mycroft 		}
    382   1.1   mycroft 	}
    383   1.1   mycroft done:
    384   1.1   mycroft #ifdef DIAGNOSTIC
    385   1.1   mycroft 	for (level = SINGLE; level <= TRIPLE; level++)
    386  1.14    bouyer 		if (newblks[NDADDR + level] != oip->i_ffs_ib[level])
    387   1.1   mycroft 			panic("itrunc1");
    388   1.1   mycroft 	for (i = 0; i < NDADDR; i++)
    389  1.14    bouyer 		if (newblks[i] != oip->i_ffs_db[i])
    390   1.1   mycroft 			panic("itrunc2");
    391   1.1   mycroft 	if (length == 0 &&
    392   1.1   mycroft 	    (ovp->v_dirtyblkhd.lh_first || ovp->v_cleanblkhd.lh_first))
    393   1.1   mycroft 		panic("itrunc3");
    394   1.1   mycroft #endif /* DIAGNOSTIC */
    395   1.1   mycroft 	/*
    396   1.1   mycroft 	 * Put back the real size.
    397   1.1   mycroft 	 */
    398  1.14    bouyer 	oip->i_ffs_size = length;
    399  1.14    bouyer 	oip->i_ffs_blocks -= blocksreleased;
    400  1.14    bouyer 	if (oip->i_ffs_blocks < 0)			/* sanity */
    401  1.14    bouyer 		oip->i_ffs_blocks = 0;
    402   1.1   mycroft 	oip->i_flag |= IN_CHANGE;
    403   1.1   mycroft #ifdef QUOTA
    404   1.1   mycroft 	(void) chkdq(oip, -blocksreleased, NOCRED, 0);
    405   1.1   mycroft #endif
    406   1.1   mycroft 	return (allerror);
    407   1.1   mycroft }
    408   1.1   mycroft 
    409   1.1   mycroft /*
    410   1.1   mycroft  * Release blocks associated with the inode ip and stored in the indirect
    411   1.1   mycroft  * block bn.  Blocks are free'd in LIFO order up to (but not including)
    412   1.1   mycroft  * lastbn.  If level is greater than SINGLE, the block is an indirect block
    413   1.1   mycroft  * and recursive calls to indirtrunc must be used to cleanse other indirect
    414   1.1   mycroft  * blocks.
    415   1.1   mycroft  *
    416   1.1   mycroft  * NB: triple indirect blocks are untested.
    417   1.1   mycroft  */
    418   1.1   mycroft static int
    419   1.1   mycroft ffs_indirtrunc(ip, lbn, dbn, lastbn, level, countp)
    420   1.1   mycroft 	register struct inode *ip;
    421  1.18      fvdl 	ufs_daddr_t lbn, lastbn;
    422  1.18      fvdl 	ufs_daddr_t dbn;
    423   1.1   mycroft 	int level;
    424   1.1   mycroft 	long *countp;
    425   1.1   mycroft {
    426   1.1   mycroft 	register int i;
    427   1.1   mycroft 	struct buf *bp;
    428   1.1   mycroft 	register struct fs *fs = ip->i_fs;
    429  1.18      fvdl 	register ufs_daddr_t *bap;
    430   1.1   mycroft 	struct vnode *vp;
    431  1.18      fvdl 	ufs_daddr_t *copy = NULL, nb, nlbn, last;
    432   1.1   mycroft 	long blkcount, factor;
    433   1.1   mycroft 	int nblocks, blocksreleased = 0;
    434   1.1   mycroft 	int error = 0, allerror = 0;
    435   1.1   mycroft 
    436   1.1   mycroft 	/*
    437   1.1   mycroft 	 * Calculate index in current block of last
    438   1.1   mycroft 	 * block to be kept.  -1 indicates the entire
    439   1.1   mycroft 	 * block so we need not calculate the index.
    440   1.1   mycroft 	 */
    441   1.1   mycroft 	factor = 1;
    442   1.1   mycroft 	for (i = SINGLE; i < level; i++)
    443   1.1   mycroft 		factor *= NINDIR(fs);
    444   1.1   mycroft 	last = lastbn;
    445   1.1   mycroft 	if (lastbn > 0)
    446   1.1   mycroft 		last /= factor;
    447   1.1   mycroft 	nblocks = btodb(fs->fs_bsize);
    448   1.1   mycroft 	/*
    449   1.1   mycroft 	 * Get buffer of block pointers, zero those entries corresponding
    450   1.1   mycroft 	 * to blocks to be free'd, and update on disk copy first.  Since
    451   1.1   mycroft 	 * double(triple) indirect before single(double) indirect, calls
    452   1.1   mycroft 	 * to bmap on these blocks will fail.  However, we already have
    453   1.1   mycroft 	 * the on disk address, so we have to set the b_blkno field
    454   1.1   mycroft 	 * explicitly instead of letting bread do everything for us.
    455   1.1   mycroft 	 */
    456   1.1   mycroft 	vp = ITOV(ip);
    457   1.1   mycroft 	bp = getblk(vp, lbn, (int)fs->fs_bsize, 0, 0);
    458   1.1   mycroft 	if (bp->b_flags & (B_DONE | B_DELWRI)) {
    459   1.1   mycroft 		/* Braces must be here in case trace evaluates to nothing. */
    460   1.1   mycroft 		trace(TR_BREADHIT, pack(vp, fs->fs_bsize), lbn);
    461   1.1   mycroft 	} else {
    462   1.1   mycroft 		trace(TR_BREADMISS, pack(vp, fs->fs_bsize), lbn);
    463   1.1   mycroft 		curproc->p_stats->p_ru.ru_inblock++;	/* pay for read */
    464   1.1   mycroft 		bp->b_flags |= B_READ;
    465   1.1   mycroft 		if (bp->b_bcount > bp->b_bufsize)
    466   1.1   mycroft 			panic("ffs_indirtrunc: bad buffer size");
    467   1.1   mycroft 		bp->b_blkno = dbn;
    468   1.1   mycroft 		VOP_STRATEGY(bp);
    469   1.1   mycroft 		error = biowait(bp);
    470   1.1   mycroft 	}
    471   1.1   mycroft 	if (error) {
    472   1.1   mycroft 		brelse(bp);
    473   1.1   mycroft 		*countp = 0;
    474   1.1   mycroft 		return (error);
    475   1.1   mycroft 	}
    476   1.1   mycroft 
    477  1.18      fvdl 	bap = (ufs_daddr_t *)bp->b_data;
    478  1.12   thorpej 	if (lastbn != -1) {
    479  1.18      fvdl 		MALLOC(copy, ufs_daddr_t *, fs->fs_bsize, M_TEMP, M_WAITOK);
    480  1.22     perry 		memcpy((caddr_t)copy, (caddr_t)bap, (u_int)fs->fs_bsize);
    481  1.22     perry 		memset((caddr_t)&bap[last + 1], 0,
    482  1.18      fvdl 		  (u_int)(NINDIR(fs) - (last + 1)) * sizeof (ufs_daddr_t));
    483  1.12   thorpej 		error = bwrite(bp);
    484  1.12   thorpej 		if (error)
    485  1.12   thorpej 			allerror = error;
    486  1.12   thorpej 		bap = copy;
    487  1.12   thorpej 	}
    488   1.1   mycroft 
    489   1.1   mycroft 	/*
    490   1.1   mycroft 	 * Recursively free totally unused blocks.
    491   1.1   mycroft 	 */
    492   1.1   mycroft 	for (i = NINDIR(fs) - 1, nlbn = lbn + 1 - i * factor; i > last;
    493   1.1   mycroft 	    i--, nlbn += factor) {
    494  1.19    bouyer 		nb = ufs_rw32(bap[i], UFS_MPNEEDSWAP(vp->v_mount));
    495   1.1   mycroft 		if (nb == 0)
    496   1.1   mycroft 			continue;
    497   1.1   mycroft 		if (level > SINGLE) {
    498   1.9  christos 			error = ffs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
    499  1.18      fvdl 					       (ufs_daddr_t)-1, level - 1,
    500   1.9  christos 					       &blkcount);
    501   1.9  christos 			if (error)
    502   1.1   mycroft 				allerror = error;
    503   1.1   mycroft 			blocksreleased += blkcount;
    504   1.1   mycroft 		}
    505   1.1   mycroft 		ffs_blkfree(ip, nb, fs->fs_bsize);
    506   1.1   mycroft 		blocksreleased += nblocks;
    507   1.1   mycroft 	}
    508   1.1   mycroft 
    509   1.1   mycroft 	/*
    510   1.1   mycroft 	 * Recursively free last partial block.
    511   1.1   mycroft 	 */
    512   1.1   mycroft 	if (level > SINGLE && lastbn >= 0) {
    513   1.1   mycroft 		last = lastbn % factor;
    514  1.19    bouyer 		nb = ufs_rw32(bap[i], UFS_MPNEEDSWAP(vp->v_mount));
    515   1.1   mycroft 		if (nb != 0) {
    516   1.9  christos 			error = ffs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
    517   1.9  christos 					       last, level - 1, &blkcount);
    518   1.9  christos 			if (error)
    519   1.1   mycroft 				allerror = error;
    520   1.1   mycroft 			blocksreleased += blkcount;
    521   1.1   mycroft 		}
    522   1.1   mycroft 	}
    523  1.12   thorpej 
    524  1.12   thorpej 	if (copy != NULL) {
    525  1.12   thorpej 		FREE(copy, M_TEMP);
    526  1.12   thorpej 	} else {
    527  1.12   thorpej 		bp->b_flags |= B_INVAL;
    528  1.12   thorpej 		brelse(bp);
    529  1.12   thorpej 	}
    530  1.12   thorpej 
    531   1.1   mycroft 	*countp = blocksreleased;
    532   1.1   mycroft 	return (allerror);
    533   1.1   mycroft }
    534