date and time created 93/06/01 16:44:56 by bostic
[unix-history] / usr / src / sys / ufs / ffs / ffs_inode.c
index df6de48..49f9cad 100644 (file)
  * Copyright (c) 1982, 1986, 1989 Regents of the University of California.
  * All rights reserved.
  *
  * Copyright (c) 1982, 1986, 1989 Regents of the University of California.
  * All rights reserved.
  *
- * Redistribution and use in source and binary forms are permitted
- * provided that the above copyright notice and this paragraph are
- * duplicated in all such forms and that any documentation,
- * advertising materials, and other materials related to such
- * distribution and use acknowledge that the software was developed
- * by the University of California, Berkeley.  The name of the
- * University may not be used to endorse or promote products derived
- * from this software without specific prior written permission.
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
- * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
- * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ * %sccs.include.redist.c%
  *
  *
- *     @(#)ffs_inode.c 7.11 (Berkeley) %G%
+ *     @(#)ffs_inode.c 7.70 (Berkeley) %G%
  */
 
  */
 
-#include "param.h"
-#include "systm.h"
-#include "mount.h"
-#include "user.h"
-#include "file.h"
-#include "buf.h"
-#include "cmap.h"
-#include "vnode.h"
-#include "../ufs/inode.h"
-#include "../ufs/fs.h"
-#include "../ufs/ufsmount.h"
-#ifdef QUOTA
-#include "../ufs/quota.h"
-#endif
-#include "kernel.h"
-#include "malloc.h"
-
-#define        INOHSZ  512
-#if    ((INOHSZ&(INOHSZ-1)) == 0)
-#define        INOHASH(dev,ino)        (((dev)+(ino))&(INOHSZ-1))
-#else
-#define        INOHASH(dev,ino)        (((unsigned)((dev)+(ino)))%INOHSZ)
-#endif
-
-#define INSFREE(ip) {\
-       if (ifreeh) { \
-               *ifreet = (ip); \
-               (ip)->i_freeb = ifreet; \
-       } else { \
-               ifreeh = (ip); \
-               (ip)->i_freeb = &ifreeh; \
-       } \
-       (ip)->i_freef = NULL; \
-       ifreet = &(ip)->i_freef; \
-}
-
-union ihead {                          /* inode LRU cache, Chris Maltby */
-       union  ihead *ih_head[2];
-       struct inode *ih_chain[2];
-} ihead[INOHSZ];
-
-struct inode *ifreeh, **ifreet, *bdevlisth;
-
-/*
- * Initialize hash links for inodes
- * and build inode free list.
- */
-ihinit()
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/mount.h>
+#include <sys/proc.h>
+#include <sys/file.h>
+#include <sys/buf.h>
+#include <sys/vnode.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+#include <sys/trace.h>
+#include <sys/resourcevar.h>
+
+#include <vm/vm.h>
+
+#include <ufs/ufs/quota.h>
+#include <ufs/ufs/inode.h>
+#include <ufs/ufs/ufsmount.h>
+#include <ufs/ufs/ufs_extern.h>
+
+#include <ufs/ffs/fs.h>
+#include <ufs/ffs/ffs_extern.h>
+
+static int ffs_indirtrunc __P((struct inode *, daddr_t, daddr_t, daddr_t, int,
+           long *));
+
+int
+ffs_init()
 {
 {
-       register int i;
-       register struct inode *ip = inode;
-       register union  ihead *ih = ihead;
-
-       for (i = INOHSZ; --i >= 0; ih++) {
-               ih->ih_head[0] = ih;
-               ih->ih_head[1] = ih;
-       }
-       ifreeh = ip;
-       ifreet = &ip->i_freef;
-       ip->i_freeb = &ifreeh;
-       ip->i_forw = ip;
-       ip->i_back = ip;
-       ITOV(ip)->v_data = (qaddr_t)ip;
-       for (i = ninode; --i > 0; ) {
-               ++ip;
-               ip->i_forw = ip;
-               ip->i_back = ip;
-               ITOV(ip)->v_data = (qaddr_t)ip;
-               *ifreet = ip;
-               ip->i_freeb = ifreet;
-               ifreet = &ip->i_freef;
-       }
-       ip->i_freef = NULL;
+       return (ufs_init());
 }
 
 /*
 }
 
 /*
- * Look up an vnode/inode by device,inumber.
- * If it is in core (in the inode structure),
- * honor the locking protocol.
- * If it is not in core, read it in from the
- * specified device.
- * Callers must check for mount points!!
- * In all cases, a pointer to a locked
- * inode structure is returned.
+ * Update the access, modified, and inode change times as specified
+ * by the IACC, IUPD, and ICHG flags respectively. The IMOD flag
+ * is used to specify that the inode needs to be updated but that
+ * the times have already been set. The access and modified times
+ * are taken from the second and third parameters; the inode change
+ * time is always taken from the current time. If waitfor is set,
+ * then wait for the disk write of the inode to complete.
  */
  */
-iget(xp, ino, ipp)
-       struct inode *xp;
-       ino_t ino;
-       struct inode **ipp;
+int
+ffs_update(ap)
+       struct vop_update_args /* {
+               struct vnode *a_vp;
+               struct timeval *a_ta;
+               struct timeval *a_tm;
+               int a_waitfor;
+       } */ *ap;
 {
 {
-       dev_t dev = xp->i_dev;
-       struct mount *mntp = ITOV(xp)->v_mount;
-       register struct fs *fs = VFSTOUFS(mntp)->um_fs;
-       register struct inode *ip, *iq;
-       register struct vnode *vp;
-       struct inode *nip;
        struct buf *bp;
        struct buf *bp;
-       struct dinode tdip, *dp;
-       union  ihead *ih;
-       int error;
-
-loop:
-       ih = &ihead[INOHASH(dev, ino)];
-       for (ip = ih->ih_chain[0]; ip != (struct inode *)ih; ip = ip->i_forw)
-               if (ino == ip->i_number && dev == ip->i_dev) {
-                       /*
-                        * Following is essentially an inline expanded
-                        * copy of igrab(), expanded inline for speed,
-                        * and so that the test for a mounted on inode
-                        * can be deferred until after we are sure that
-                        * the inode isn't busy.
-                        */
-                       if ((ip->i_flag&ILOCKED) != 0) {
-                               ip->i_flag |= IWANT;
-                               sleep((caddr_t)ip, PINOD);
-                               goto loop;
-                       }
-                       vp = ITOV(ip);
-                       if (vp->v_count == 0) {         /* ino on free list */
-                               if (iq = ip->i_freef)
-                                       iq->i_freeb = ip->i_freeb;
-                               else
-                                       ifreet = ip->i_freeb;
-                               *ip->i_freeb = iq;
-                               ip->i_freef = NULL;
-                               ip->i_freeb = NULL;
-                       }
-                       ILOCK(ip);
-                       VREF(vp);
-                       *ipp = ip;
-                       return(0);
-               }
-       if (error = getnewino(dev, ino, &nip)) {
-               *ipp = 0;
-               return (error);
-       }
-       ip = nip;
-       /*
-        * Read in the disk contents for the inode.
-        */
-       if (error = bread(VFSTOUFS(mntp)->um_devvp, fsbtodb(fs, itod(fs, ino)),
-           (int)fs->fs_bsize, &bp)) {
-               /*
-                * The inode doesn't contain anything useful, so it would
-                * be misleading to leave it on its hash chain. Iput() will
-                * take care of putting it back on the free list. We also
-                * lose its inumber, just in case.
-                */
-               remque(ip);
-               ip->i_forw = ip;
-               ip->i_back = ip;
-               ip->i_number = 0;
-               ITOV(ip)->v_type = VNON;
-               INSFREE(ip);
-               iunlock(ip);
-               ip->i_flag = 0;
-               brelse(bp);
-               *ipp = 0;
-               return(error);
-       }
-       /*
-        * Check to see if the new inode represents a block device
-        * for which we already have an inode (either because of
-        * bdevvp() or because of a different inode representing
-        * the same block device). If such an alias exists, put the
-        * just allocated inode back on the free list, and replace
-        * the contents of the existing inode with the contents of
-        * the new inode.
-        */
-       dp = bp->b_un.b_dino;
-       dp += itoo(fs, ino);
-       if ((dp->di_mode & IFMT) != IFBLK) {
-               ip->i_ic = dp->di_ic;
-               brelse(bp);
-       } else {
-again:
-               for (iq = bdevlisth; iq; iq = iq->i_devlst) {
-                       vp = ITOV(iq);
-                       if (dp->di_rdev != vp->v_rdev)
-                               continue;
-                       igrab(iq);
-                       if (dp->di_rdev != vp->v_rdev) {
-                               iput(iq);
-                               goto again;
-                       }
-                       /*
-                        * Discard unneeded inode.
-                        */
-                       remque(ip);
-                       ip->i_forw = ip;
-                       ip->i_back = ip;
-                       ip->i_number = 0;
-                       ITOV(ip)->v_type = VNON;
-                       INSFREE(ip);
-                       iunlock(ip);
-                       ip->i_flag = 0;
-                       /*
-                        * Reinitialize aliased inode.
-                        * We must release the buffer that we just read
-                        * before doing the iupdat() to avoid a possible
-                        * deadlock with updating an inode in the same
-                        * disk block.
-                        */
-                       ip = iq;
-                       tdip.di_ic = dp->di_ic;
-                       brelse(bp);
-                       error = iupdat(ip, &time, &time, 1);
-                       ip->i_ic = tdip.di_ic;
-                       remque(ip);
-                       insque(ip, ih);
-                       ip->i_dev = dev;
-                       ip->i_number = ino;
-                       if (ip->i_devvp) {
-                               vrele(ip->i_devvp);
-                               ip->i_devvp = 0;
-                       }
-                       cache_purge(vp);
-                       break;
-               }
-               if (iq == 0) {
-                       ip->i_ic = dp->di_ic;
-                       brelse(bp);
-                       ip->i_devlst = bdevlisth;
-                       bdevlisth = ip;
-               }
-       }
-       /*
-        * Finish inode initialization.
-        */
-       ip->i_fs = fs;
-       ip->i_devvp = VFSTOUFS(mntp)->um_devvp;
-       VREF(ip->i_devvp);
-       /*
-        * Initialize the associated vnode
-        */
-       vp = ITOV(ip);
-       vinit(vp, mntp, IFTOVT(ip->i_mode), &ufs_vnodeops);
-       if (vp->v_type == VCHR || vp->v_type == VBLK) {
-               vp->v_rdev = ip->i_rdev;
-               vp->v_op = &blk_vnodeops;
-       }
-       if (ino == ROOTINO)
-               vp->v_flag |= VROOT;
-#ifdef QUOTA
-       if (ip->i_mode != 0)
-               ip->i_dquot = inoquota(ip);
-#endif
-       /*
-        * Set up a generation number for this inode if it does not
-        * already have one. This should only happen on old filesystems.
-        */
-       if (ip->i_gen == 0) {
-               if (++nextgennumber < (u_long)time.tv_sec)
-                       nextgennumber = time.tv_sec;
-               ip->i_gen = nextgennumber;
-               if ((vp->v_mount->m_flag & M_RDONLY) == 0)
-                       ip->i_flag |= IMOD;
-       }
-       *ipp = ip;
-       return (0);
-}
-
-/*
- * Allocate a new inode.
- *
- * Put it onto its hash chain and lock it so that other requests for
- * this inode will block if they arrive while we are sleeping waiting
- * for old data structures to be purged or for the contents of the disk
- * portion of this inode to be read.
- */
-getnewino(dev, ino, ipp)
-       dev_t dev;
-       ino_t ino;
-       struct inode **ipp;
-{
-       union ihead *ih;
-       register struct inode *ip, *iq;
-       register struct vnode *vp;
-
-       /*
-        * Remove the next inode from the free list.
-        */
-       if ((ip = ifreeh) == NULL) {
-               tablefull("inode");
-               *ipp = 0;
-               return(ENFILE);
-       }
-       vp = ITOV(ip);
-       if (vp->v_count)
-               panic("free inode isn't");
-       if (iq = ip->i_freef)
-               iq->i_freeb = &ifreeh;
-       ifreeh = iq;
-       ip->i_freef = NULL;
-       ip->i_freeb = NULL;
-       /*
-        * Now to take inode off the hash chain it was on
-        * (initially, or after an iflush, it is on a "hash chain"
-        * consisting entirely of itself, and pointed to by no-one)
-        * and put it on the chain for its new (ino, dev) pair.
-        */
-       remque(ip);
-       ip->i_dev = dev;
-       ip->i_number = ino;
-       if (dev != NODEV) {
-               ih = &ihead[INOHASH(dev, ino)];
-               insque(ip, ih);
-       }
-       ip->i_flag = 0;
-       ILOCK(ip);
-       ip->i_lastr = 0;
-#endif SECSIZE
-       /*
-        * Purge old data structures associated with the inode.
-        */
-       cache_purge(vp);
-       if (ip->i_devvp) {
-               vrele(ip->i_devvp);
-               ip->i_devvp = 0;
-       }
-#ifdef QUOTA
-       dqrele(ip->i_dquot);
-       ip->i_dquot = NODQUOT;
-#endif
-       if (vp->v_type == VBLK) {
-               if (bdevlisth == ip) {
-                       bdevlisth = ip->i_devlst;
-               } else {
-                       for (iq = bdevlisth; iq; iq = iq->i_devlst) {
-                               if (iq->i_devlst != ip)
-                                       continue;
-                               iq->i_devlst = ip->i_devlst;
-                               break;
-                       }
-                       if (iq == NULL)
-                               panic("missing bdev");
-               }
-       }
-       *ipp = ip;
-       return (0);
-}
-
-/*
- * Convert a pointer to an inode into a reference to an inode.
- *
- * This is basically the internal piece of iget (after the
- * inode pointer is located) but without the test for mounted
- * filesystems.  It is caller's responsibility to check that
- * the inode pointer is valid.
- */
-igrab(ip)
-       register struct inode *ip;
-{
-       register struct vnode *vp = ITOV(ip);
-
-       while ((ip->i_flag&ILOCKED) != 0) {
-               ip->i_flag |= IWANT;
-               sleep((caddr_t)ip, PINOD);
-       }
-       if (vp->v_count == 0) {         /* ino on free list */
-               register struct inode *iq;
-
-               if (iq = ip->i_freef)
-                       iq->i_freeb = ip->i_freeb;
-               else
-                       ifreet = ip->i_freeb;
-               *ip->i_freeb = iq;
-               ip->i_freef = NULL;
-               ip->i_freeb = NULL;
-       }
-       VREF(vp);
-       ILOCK(ip);
-}
-
-/*
- * Create a vnode for a block device.
- * Used for root filesystem, argdev, and swap areas.
- */
-bdevvp(dev, vpp)
-       dev_t dev;
-       struct vnode **vpp;
-{
-       register struct inode *ip;
-       register struct vnode *vp;
-       struct inode *nip;
-       int error;
+       struct inode *ip;
+       struct dinode *dp;
+       register struct fs *fs;
 
 
-       /*
-        * Check for the existence of an existing vnode.
-        */
-again:
-       for (ip = bdevlisth; ip; ip = ip->i_devlst) {
-               vp = ITOV(ip);
-               if (dev != vp->v_rdev)
-                       continue;
-               igrab(ip);
-               if (dev != vp->v_rdev) {
-                       iput(ip);
-                       goto again;
-               }
-               IUNLOCK(ip);
-               *vpp = vp;
+       ip = VTOI(ap->a_vp);
+       if (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY) {
+               ip->i_flag &= ~(IUPD|IACC|ICHG|IMOD);
                return (0);
        }
                return (0);
        }
-       if (error = getnewino(NODEV, (ino_t)0, &nip)) {
-               *vpp = 0;
-               return (error);
-       }
-       ip = nip;
-       ip->i_fs = 0;
-       ip->i_devlst = bdevlisth;
-       bdevlisth = ip;
-       vp = ITOV(ip);
-       vinit(vp, 0, VBLK, &blk_vnodeops);
-       vp->v_rdev = dev;
-       IUNLOCK(ip);
-       *vpp = vp;
-       return (0);
-}
-
-/*
- * Decrement reference count of
- * an inode structure.
- * On the last reference,
- * write the inode out and if necessary,
- * truncate and deallocate the file.
- */
-iput(ip)
-       register struct inode *ip;
-{
-
-       if ((ip->i_flag & ILOCKED) == 0)
-               panic("iput");
-       IUNLOCK(ip);
-       vrele(ITOV(ip));
-}
-
-
-ufs_inactive(vp)
-       struct vnode *vp;
-{
-       register struct inode *ip = VTOI(vp);
-       int mode, error;
-
-       if (ITOV(ip)->v_count != 0)
-               panic("ufs_inactive: not inactive");
-       /*
-        * Get rid of inodes related to stale file handles.
-        */
-       if (ip->i_mode == 0)
-               goto freeit;
-       ILOCK(ip);
-       if (ip->i_nlink <= 0 && (ITOV(ip)->v_mount->m_flag&M_RDONLY) == 0) {
-               error = itrunc(ip, (u_long)0);
-               mode = ip->i_mode;
-               ip->i_mode = 0;
-               ip->i_rdev = 0;
-               ip->i_flag |= IUPD|ICHG;
-               ifree(ip, ip->i_number, mode);
-#ifdef QUOTA
-               (void) chkiq(ip->i_dev, ip, ip->i_uid, 0);
-               dqrele(ip->i_dquot);
-               ip->i_dquot = NODQUOT;
-#endif
+       if ((ip->i_flag & (IUPD|IACC|ICHG|IMOD)) == 0)
+               return (0);
+       if (ip->i_flag&IACC)
+               ip->i_atime.ts_sec = ap->a_ta->tv_sec;
+       if (ip->i_flag&IUPD) {
+               ip->i_mtime.ts_sec = ap->a_tm->tv_sec;
+               ip->i_modrev++;
        }
        }
-       IUPDAT(ip, &time, &time, 0);
-       IUNLOCK(ip);
-freeit:
-       ip->i_flag = 0;
+       if (ip->i_flag&ICHG)
+               ip->i_ctime.ts_sec = time.tv_sec;
+       ip->i_flag &= ~(IUPD|IACC|ICHG|IMOD);
+       fs = ip->i_fs;
        /*
        /*
-        * Put the inode on the end of the free list.
-        * Possibly in some cases it would be better to
-        * put the inode at the head of the free list,
-        * (eg: where i_mode == 0 || i_number == 0).
+        * Ensure that uid and gid are correct. This is a temporary
+        * fix until fsck has been changed to do the update.
         */
         */
-       INSFREE(ip);
-       return (error);
-}
-
-/*
- * Check accessed and update flags on
- * an inode structure.
- * If any is on, update the inode
- * with the current time.
- * If waitfor is given, then must insure
- * i/o order so wait for write to complete.
- */
-iupdat(ip, ta, tm, waitfor)
-       register struct inode *ip;
-       struct timeval *ta, *tm;
-       int waitfor;
-{
-       struct buf *bp;
-       struct vnode *vp = ITOV(ip);
-       struct dinode *dp;
-       register struct fs *fs;
-
-       fs = ip->i_fs;
-       if ((ip->i_flag & (IUPD|IACC|ICHG|IMOD)) == 0)
-               return (0);
-       if (vp->v_mount->m_flag & M_RDONLY)
-               return (0);
-       error = bread(ip->i_devvp, fsbtodb(fs, itod(fs, ip->i_number)),
-               (int)fs->fs_bsize, &bp);
-       if (error) {
+       if (fs->fs_inodefmt < FS_44INODEFMT) {          /* XXX */
+               ip->i_din.di_ouid = ip->i_uid;          /* XXX */
+               ip->i_din.di_ogid = ip->i_gid;          /* XXX */
+       }                                               /* XXX */
+       if (error = bread(ip->i_devvp, fsbtodb(fs, itod(fs, ip->i_number)),
+               (int)fs->fs_bsize, NOCRED, &bp)) {
                brelse(bp);
                return (error);
        }
                brelse(bp);
                return (error);
        }
-       if (ip->i_flag&IACC)
-               ip->i_atime = ta->tv_sec;
-       if (ip->i_flag&IUPD)
-               ip->i_mtime = tm->tv_sec;
-       if (ip->i_flag&ICHG)
-               ip->i_ctime = time.tv_sec;
-       ip->i_flag &= ~(IUPD|IACC|ICHG|IMOD);
        dp = bp->b_un.b_dino + itoo(fs, ip->i_number);
        dp = bp->b_un.b_dino + itoo(fs, ip->i_number);
-       dp->di_ic = ip->i_ic;
-       if (waitfor) {
+       *dp = ip->i_din;
+       if (ap->a_waitfor)
                return (bwrite(bp));
                return (bwrite(bp));
-       else {
+       else {
                bdwrite(bp);
                return (0);
        }
                bdwrite(bp);
                return (0);
        }
@@ -546,45 +105,51 @@ iupdat(ip, ta, tm, waitfor)
 #define        DOUBLE  1       /* index of double indirect block */
 #define        TRIPLE  2       /* index of triple indirect block */
 /*
 #define        DOUBLE  1       /* index of double indirect block */
 #define        TRIPLE  2       /* index of triple indirect block */
 /*
- * Truncate the inode ip to at most
- * length size.  Free affected disk
- * blocks -- the blocks of the file
- * are removed in reverse order.
- *
- * NB: triple indirect blocks are untested.
+ * Truncate the inode oip to at most length size.  Free affected disk
+ * blocks -- the blocks of the file are removed in reverse order.
  */
  */
-itrunc(oip, length)
-       register struct inode *oip;
-       u_long length;
+ffs_truncate(ap)
+       struct vop_truncate_args /* {
+               struct vnode *a_vp;
+               off_t a_length;
+               int a_flags;
+               struct ucred *a_cred;
+               struct proc *a_p;
+       } */ *ap;
 {
 {
+       register struct vnode *ovp = ap->a_vp;
        register daddr_t lastblock;
        register daddr_t lastblock;
-       daddr_t bn, lbn, lastiblock[NIADDR];
+       register struct inode *oip;
+       daddr_t bn, lbn, lastiblock[NIADDR], indir_lbn[NIADDR];
+       daddr_t oldblks[NDADDR + NIADDR], newblks[NDADDR + NIADDR];
+       off_t length = ap->a_length;
        register struct fs *fs;
        register struct fs *fs;
-       register struct inode *ip;
        struct buf *bp;
        struct buf *bp;
-       int offset, osize, size, level;
-       long count, nblocks, blocksreleased = 0;
+       int offset, size, level;
+       long count, nblocks, vflags, blocksreleased = 0;
+       struct timeval tv;
        register int i;
        register int i;
-       int error, allerror = 0;
-       struct inode tip;
-
-       if (oip->i_size <= length) {
+       int aflags, error, allerror;
+       off_t osize;
+
+       oip = VTOI(ovp);
+       tv = time;
+       if (ovp->v_type == VLNK &&
+           oip->i_size < ovp->v_mount->mnt_maxsymlinklen) {
+#ifdef DIAGNOSTIC
+               if (length != 0)
+                       panic("ffs_truncate: partial truncate of symlink");
+#endif
+               bzero((char *)&oip->i_shortlink, (u_int)oip->i_size);
+               oip->i_size = 0;
                oip->i_flag |= ICHG|IUPD;
                oip->i_flag |= ICHG|IUPD;
-               error = iupdat(oip, &time, &time, 1);
-               return (error);
+               return (VOP_UPDATE(ovp, &tv, &tv, 1));
        }
        }
-       /*
-        * Calculate index into inode's block list of
-        * last direct and indirect blocks (if any)
-        * which we want to keep.  Lastblock is -1 when
-        * the file is truncated to 0.
-        */
-       fs = oip->i_fs;
-       lastblock = lblkno(fs, length + fs->fs_bsize - 1) - 1;
-       lastiblock[SINGLE] = lastblock - NDADDR;
-       lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
-       lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
-       nblocks = btodb(fs->fs_bsize);
+       if (oip->i_size == length) {
+               oip->i_flag |= ICHG|IUPD;
+               return (VOP_UPDATE(ovp, &tv, &tv, 0));
+       }
+       vnode_pager_setsize(ovp, (u_long)length);
        /*
         * Update the size of the file. If the file is not being
         * truncated to a block boundry, the contents of the
        /*
         * Update the size of the file. If the file is not being
         * truncated to a block boundry, the contents of the
@@ -592,40 +157,56 @@ itrunc(oip, length)
         * zero'ed in case it ever become accessable again because
         * of subsequent file growth.
         */
         * zero'ed in case it ever become accessable again because
         * of subsequent file growth.
         */
+       fs = oip->i_fs;
        osize = oip->i_size;
        offset = blkoff(fs, length);
        osize = oip->i_size;
        offset = blkoff(fs, length);
-       if (offset == 0) {
+       if (offset == 0 && osize > length) {
                oip->i_size = length;
        } else {
                lbn = lblkno(fs, length);
                oip->i_size = length;
        } else {
                lbn = lblkno(fs, length);
-               error = balloc(oip, lbn, offset, &bn, B_CLRBUF);
-               if (error)
+               aflags = B_CLRBUF;
+               if (ap->a_flags & IO_SYNC)
+                       aflags |= B_SYNC;
+#ifdef QUOTA
+               if (error = getinoquota(oip))
+                       return (error);
+#endif
+               if (error = ffs_balloc(oip, lbn, offset, ap->a_cred, &bp, aflags))
                        return (error);
                        return (error);
-               if ((long)bn < 0)
-                       panic("itrunc: hole");
                oip->i_size = length;
                size = blksize(fs, oip, lbn);
                oip->i_size = length;
                size = blksize(fs, oip, lbn);
-               count = howmany(size, CLBYTES);
-                       munhash(oip->i_devvp, bn + i * CLBYTES / DEV_BSIZE);
-               error = bread(oip->i_devvp, bn, size, &bp);
-               if (error) {
-                       oip->i_size = osize;
-                       brelse(bp);
-                       return (error);
+               (void) vnode_pager_uncache(ovp);
+               if (osize > length) {
+                       bzero(bp->b_un.b_addr + offset, (u_int)(size - offset));
+                       allocbuf(bp, size);
+               }
+               if (ap->a_flags & IO_SYNC)
+                       bwrite(bp);
+               else
+                       bawrite(bp);
+               if (osize < length) {
+                       oip->i_flag |= ICHG|IUPD;
+                       return (VOP_UPDATE(ovp, &tv, &tv, 1));
                }
                }
-               bzero(bp->b_un.b_addr + offset, (unsigned)(size - offset));
-               bdwrite(bp);
        }
        /*
        }
        /*
-        * Update file and block pointers
-        * on disk before we start freeing blocks.
-        * If we crash before free'ing blocks below,
-        * the blocks will be returned to the free list.
-        * lastiblock values are also normalized to -1
-        * for calls to indirtrunc below.
+        * Calculate index into inode's block list of
+        * last direct and indirect blocks (if any)
+        * which we want to keep.  Lastblock is -1 when
+        * the file is truncated to 0.
+        */
+       lastblock = lblkno(fs, length + fs->fs_bsize - 1) - 1;
+       lastiblock[SINGLE] = lastblock - NDADDR;
+       lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
+       lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
+       nblocks = btodb(fs->fs_bsize);
+       /*
+        * Update file and block pointers on disk before we start freeing
+        * blocks.  If we crash before free'ing blocks below, the blocks
+        * will be returned to the free list.  lastiblock values are also
+        * normalized to -1 for calls to ffs_indirtrunc below.
         */
         */
-       tip = *oip;
-       tip.i_size = osize;
+       bcopy((caddr_t)&oip->i_db[0], (caddr_t)oldblks, sizeof oldblks);
        for (level = TRIPLE; level >= SINGLE; level--)
                if (lastiblock[level] < 0) {
                        oip->i_ib[level] = 0;
        for (level = TRIPLE; level >= SINGLE; level--)
                if (lastiblock[level] < 0) {
                        oip->i_ib[level] = 0;
@@ -634,23 +215,37 @@ itrunc(oip, length)
        for (i = NDADDR - 1; i > lastblock; i--)
                oip->i_db[i] = 0;
        oip->i_flag |= ICHG|IUPD;
        for (i = NDADDR - 1; i > lastblock; i--)
                oip->i_db[i] = 0;
        oip->i_flag |= ICHG|IUPD;
-       allerror = syncip(oip);
+       if (error = VOP_UPDATE(ovp, &tv, &tv, MNT_WAIT))
+               allerror = error;
+       /*
+        * Having written the new inode to disk, save its new configuration
+        * and put back the old block pointers long enough to process them.
+        * Note that we save the new block configuration so we can check it
+        * when we are done.
+        */
+       bcopy((caddr_t)&oip->i_db[0], (caddr_t)newblks, sizeof newblks);
+       bcopy((caddr_t)oldblks, (caddr_t)&oip->i_db[0], sizeof oldblks);
+       oip->i_size = osize;
+       vflags = ((length > 0) ? V_SAVE : 0) | V_SAVEMETA;
+       allerror = vinvalbuf(ovp, vflags, ap->a_cred, ap->a_p, 0, 0);
 
        /*
         * Indirect blocks first.
         */
 
        /*
         * Indirect blocks first.
         */
-       ip = &tip;
+       indir_lbn[SINGLE] = -NDADDR;
+       indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) - 1;
+       indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1;
        for (level = TRIPLE; level >= SINGLE; level--) {
        for (level = TRIPLE; level >= SINGLE; level--) {
-               bn = ip->i_ib[level];
+               bn = oip->i_ib[level];
                if (bn != 0) {
                if (bn != 0) {
-                       error = indirtrunc(ip, bn, lastiblock[level], level,
-                               &count);
+                       error = ffs_indirtrunc(oip, indir_lbn[level],
+                           fsbtodb(fs, bn), lastiblock[level], level, &count);
                        if (error)
                                allerror = error;
                        blocksreleased += count;
                        if (lastiblock[level] < 0) {
                        if (error)
                                allerror = error;
                        blocksreleased += count;
                        if (lastiblock[level] < 0) {
-                               ip->i_ib[level] = 0;
-                               blkfree(ip, bn, (off_t)fs->fs_bsize);
+                               oip->i_ib[level] = 0;
+                               ffs_blkfree(oip, bn, fs->fs_bsize);
                                blocksreleased += nblocks;
                        }
                }
                                blocksreleased += nblocks;
                        }
                }
@@ -662,14 +257,14 @@ itrunc(oip, length)
         * All whole direct blocks or frags.
         */
        for (i = NDADDR - 1; i > lastblock; i--) {
         * All whole direct blocks or frags.
         */
        for (i = NDADDR - 1; i > lastblock; i--) {
-               register off_t bsize;
+               register long bsize;
 
 
-               bn = ip->i_db[i];
+               bn = oip->i_db[i];
                if (bn == 0)
                        continue;
                if (bn == 0)
                        continue;
-               ip->i_db[i] = 0;
-               bsize = (off_t)blksize(fs, ip, i);
-               blkfree(ip, bn, bsize);
+               oip->i_db[i] = 0;
+               bsize = blksize(fs, oip, i);
+               ffs_blkfree(oip, bn, bsize);
                blocksreleased += btodb(bsize);
        }
        if (lastblock < 0)
                blocksreleased += btodb(bsize);
        }
        if (lastblock < 0)
@@ -679,17 +274,17 @@ itrunc(oip, length)
         * Finally, look for a change in size of the
         * last direct block; release any frags.
         */
         * Finally, look for a change in size of the
         * last direct block; release any frags.
         */
-       bn = ip->i_db[lastblock];
+       bn = oip->i_db[lastblock];
        if (bn != 0) {
        if (bn != 0) {
-               off_t oldspace, newspace;
+               long oldspace, newspace;
 
                /*
                 * Calculate amount of space we're giving
                 * back as old block size minus new block size.
                 */
 
                /*
                 * Calculate amount of space we're giving
                 * back as old block size minus new block size.
                 */
-               oldspace = blksize(fs, ip, lastblock);
-               ip->i_size = length;
-               newspace = blksize(fs, ip, lastblock);
+               oldspace = blksize(fs, oip, lastblock);
+               oip->i_size = length;
+               newspace = blksize(fs, oip, lastblock);
                if (newspace == 0)
                        panic("itrunc: newspace");
                if (oldspace - newspace > 0) {
                if (newspace == 0)
                        panic("itrunc: newspace");
                if (oldspace - newspace > 0) {
@@ -699,42 +294,51 @@ itrunc(oip, length)
                         * required for the storage we're keeping.
                         */
                        bn += numfrags(fs, newspace);
                         * required for the storage we're keeping.
                         */
                        bn += numfrags(fs, newspace);
-                       blkfree(ip, bn, oldspace - newspace);
+                       ffs_blkfree(oip, bn, oldspace - newspace);
                        blocksreleased += btodb(oldspace - newspace);
                }
        }
 done:
                        blocksreleased += btodb(oldspace - newspace);
                }
        }
 done:
-/* BEGIN PARANOIA */
+#ifdef DIAGNOSTIC
        for (level = SINGLE; level <= TRIPLE; level++)
        for (level = SINGLE; level <= TRIPLE; level++)
-               if (ip->i_ib[level] != oip->i_ib[level])
+               if (newblks[NDADDR + level] != oip->i_ib[level])
                        panic("itrunc1");
        for (i = 0; i < NDADDR; i++)
                        panic("itrunc1");
        for (i = 0; i < NDADDR; i++)
-               if (ip->i_db[i] != oip->i_db[i])
+               if (newblks[i] != oip->i_db[i])
                        panic("itrunc2");
                        panic("itrunc2");
-/* END PARANOIA */
+       if (length == 0 &&
+           (ovp->v_dirtyblkhd.le_next || ovp->v_cleanblkhd.le_next))
+               panic("itrunc3");
+#endif /* DIAGNOSTIC */
+       /*
+        * Put back the real size.
+        */
+       oip->i_size = length;
        oip->i_blocks -= blocksreleased;
        if (oip->i_blocks < 0)                  /* sanity */
                oip->i_blocks = 0;
        oip->i_flag |= ICHG;
 #ifdef QUOTA
        oip->i_blocks -= blocksreleased;
        if (oip->i_blocks < 0)                  /* sanity */
                oip->i_blocks = 0;
        oip->i_flag |= ICHG;
 #ifdef QUOTA
-       (void) chkdq(oip, -blocksreleased, 0);
+       if (!getinoquota(oip))
+               (void) chkdq(oip, -blocksreleased, NOCRED, 0);
 #endif
        return (allerror);
 }
 
 /*
 #endif
        return (allerror);
 }
 
 /*
- * Release blocks associated with the inode ip and
- * stored in the indirect block bn.  Blocks are free'd
- * in LIFO order up to (but not including) lastbn.  If
- * level is greater than SINGLE, the block is an indirect
- * block and recursive calls to indirtrunc must be used to
- * cleanse other indirect blocks.
+ * Release blocks associated with the inode ip and stored in the indirect
+ * block bn.  Blocks are free'd in LIFO order up to (but not including)
+ * lastbn.  If level is greater than SINGLE, the block is an indirect block
+ * and recursive calls to indirtrunc must be used to cleanse other indirect
+ * blocks.
  *
  * NB: triple indirect blocks are untested.
  */
  *
  * NB: triple indirect blocks are untested.
  */
-indirtrunc(ip, bn, lastbn, level, countp)
+static int
+ffs_indirtrunc(ip, lbn, dbn, lastbn, level, countp)
        register struct inode *ip;
        register struct inode *ip;
-       daddr_t bn, lastbn;
+       daddr_t lbn, lastbn;
+       daddr_t dbn;
        int level;
        long *countp;
 {
        int level;
        long *countp;
 {
@@ -742,10 +346,11 @@ indirtrunc(ip, bn, lastbn, level, countp)
        struct buf *bp;
        register struct fs *fs = ip->i_fs;
        register daddr_t *bap;
        struct buf *bp;
        register struct fs *fs = ip->i_fs;
        register daddr_t *bap;
-       daddr_t *copy, nb, last;
+       struct vnode *vp;
+       daddr_t *copy, nb, nlbn, last;
        long blkcount, factor;
        int nblocks, blocksreleased = 0;
        long blkcount, factor;
        int nblocks, blocksreleased = 0;
-       int error, allerror = 0;
+       int error = 0, allerror = 0;
 
        /*
         * Calculate index in current block of last
 
        /*
         * Calculate index in current block of last
@@ -760,25 +365,45 @@ indirtrunc(ip, bn, lastbn, level, countp)
                last /= factor;
        nblocks = btodb(fs->fs_bsize);
        /*
                last /= factor;
        nblocks = btodb(fs->fs_bsize);
        /*
-        * Get buffer of block pointers, zero those 
-        * entries corresponding to blocks to be free'd,
-        * and update on disk copy first.
+        * Get buffer of block pointers, zero those entries corresponding
+        * to blocks to be free'd, and update on disk copy first.  Since
+        * double(triple) indirect before single(double) indirect, calls
+        * to bmap on these blocks will fail.  However, we already have
+        * the on disk address, so we have to set the b_blkno field
+        * explicitly instead of letting bread do everything for us.
         */
 #ifdef SECSIZE
        bp = bread(ip->i_dev, fsbtodb(fs, bn), (int)fs->fs_bsize,
            fs->fs_dbsize);
 #else SECSIZE
         */
 #ifdef SECSIZE
        bp = bread(ip->i_dev, fsbtodb(fs, bn), (int)fs->fs_bsize,
            fs->fs_dbsize);
 #else SECSIZE
-       error = bread(ip->i_devvp, fsbtodb(fs, bn), (int)fs->fs_bsize, &bp);
+       vp = ITOV(ip);
+       bp = getblk(vp, lbn, (int)fs->fs_bsize, 0, 0);
+       if (bp->b_flags & (B_DONE | B_DELWRI)) {
+               /* Braces must be here in case trace evaluates to nothing. */
+               trace(TR_BREADHIT, pack(vp, fs->fs_bsize), lbn);
+       } else {
+               trace(TR_BREADMISS, pack(vp, fs->fs_bsize), lbn);
+               curproc->p_stats->p_ru.ru_inblock++;    /* pay for read */
+               bp->b_flags |= B_READ;
+               if (bp->b_bcount > bp->b_bufsize)
+                       panic("ffs_indirtrunc: bad buffer size");
+               bp->b_blkno = dbn;
+               VOP_STRATEGY(bp);
+               error = biowait(bp);
+       }
        if (error) {
                brelse(bp);
                *countp = 0;
                return (error);
        }
        if (error) {
                brelse(bp);
                *countp = 0;
                return (error);
        }
+
        bap = bp->b_un.b_daddr;
        MALLOC(copy, daddr_t *, fs->fs_bsize, M_TEMP, M_WAITOK);
        bcopy((caddr_t)bap, (caddr_t)copy, (u_int)fs->fs_bsize);
        bzero((caddr_t)&bap[last + 1],
          (u_int)(NINDIR(fs) - (last + 1)) * sizeof (daddr_t));
        bap = bp->b_un.b_daddr;
        MALLOC(copy, daddr_t *, fs->fs_bsize, M_TEMP, M_WAITOK);
        bcopy((caddr_t)bap, (caddr_t)copy, (u_int)fs->fs_bsize);
        bzero((caddr_t)&bap[last + 1],
          (u_int)(NINDIR(fs) - (last + 1)) * sizeof (daddr_t));
+       if (last == -1)
+               bp->b_flags |= B_INVAL;
        error = bwrite(bp);
        if (error)
                allerror = error;
        error = bwrite(bp);
        if (error)
                allerror = error;
@@ -787,18 +412,18 @@ indirtrunc(ip, bn, lastbn, level, countp)
        /*
         * Recursively free totally unused blocks.
         */
        /*
         * Recursively free totally unused blocks.
         */
-       for (i = NINDIR(fs) - 1; i > last; i--) {
+       for (i = NINDIR(fs) - 1, nlbn = lbn + 1 - i * factor; i > last;
+           i--, nlbn += factor) {
                nb = bap[i];
                if (nb == 0)
                        continue;
                if (level > SINGLE) {
                nb = bap[i];
                if (nb == 0)
                        continue;
                if (level > SINGLE) {
-                       error = indirtrunc(ip, nb, (daddr_t)-1, level - 1,
-                               &blkcount);
-                       if (error)
+                       if (error = ffs_indirtrunc(ip, nlbn,
+                           fsbtodb(fs, nb), (daddr_t)-1, level - 1, &blkcount))
                                allerror = error;
                        blocksreleased += blkcount;
                }
                                allerror = error;
                        blocksreleased += blkcount;
                }
-               blkfree(ip, nb, (off_t)fs->fs_bsize);
+               ffs_blkfree(ip, nb, fs->fs_bsize);
                blocksreleased += nblocks;
        }
 
                blocksreleased += nblocks;
        }
 
@@ -809,8 +434,8 @@ indirtrunc(ip, bn, lastbn, level, countp)
                last = lastbn % factor;
                nb = bap[i];
                if (nb != 0) {
                last = lastbn % factor;
                nb = bap[i];
                if (nb != 0) {
-                       error = indirtrunc(ip, nb, last, level - 1, &blkcount);
-                       if (error)
+                       if (error = ffs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
+                           last, level - 1, &blkcount))
                                allerror = error;
                        blocksreleased += blkcount;
                }
                                allerror = error;
                        blocksreleased += blkcount;
                }
@@ -819,128 +444,3 @@ indirtrunc(ip, bn, lastbn, level, countp)
        *countp = blocksreleased;
        return (allerror);
 }
        *countp = blocksreleased;
        return (allerror);
 }
-
-/*
- * Remove any inodes in the inode cache belonging to dev.
- *
- * There should not be any active ones, return error if any are found
- * (nb: this is a user error, not a system err).
- */
-#ifdef QUOTA
-iflush(dev, iq)
-       dev_t dev;
-       struct inode *iq;
-#else
-iflush(dev)
-       dev_t dev;
-#endif
-{
-       register struct inode *ip;
-
-       for (ip = inode; ip < inodeNINODE; ip++) {
-#ifdef QUOTA
-               if (ip != iq && ip->i_dev == dev)
-#else
-               if (ip->i_dev == dev)
-#endif
-                       if (ITOV(ip)->v_count)
-                               return (EBUSY);
-                       else {
-                               remque(ip);
-                               ip->i_forw = ip;
-                               ip->i_back = ip;
-                               /*
-                                * as v_count == 0, the inode was on the free
-                                * list already, just leave it there, it will
-                                * fall off the bottom eventually. We could
-                                * perhaps move it to the head of the free
-                                * list, but as umounts are done so
-                                * infrequently, we would gain very little,
-                                * while making the code bigger.
-                                */
-#ifdef QUOTA
-                               dqrele(ip->i_dquot);
-                               ip->i_dquot = NODQUOT;
-#endif
-                               if (ip->i_devvp) {
-                                       vrele(ip->i_devvp);
-                                       ip->i_devvp = 0;
-                               }
-                       }
-       }
-       return (0);
-}
-
-/*
- * Lock an inode. If its already locked, set the WANT bit and sleep.
- */
-ilock(ip)
-       register struct inode *ip;
-{
-
-       while (ip->i_flag & ILOCKED) {
-               ip->i_flag |= IWANT;
-               (void) sleep((caddr_t)ip, PINOD);
-       }
-       ip->i_flag |= ILOCKED;
-}
-
-/*
- * Unlock an inode.  If WANT bit is on, wakeup.
- */
-iunlock(ip)
-       register struct inode *ip;
-{
-
-       if ((ip->i_flag & ILOCKED) == 0)
-               printf("unlocking unlocked inode %d on dev 0x%x\n",
-                       ip->i_number, ip->i_dev);
-       ip->i_flag &= ~ILOCKED;
-       if (ip->i_flag&IWANT) {
-               ip->i_flag &= ~IWANT;
-               wakeup((caddr_t)ip);
-       }
-}
-
-/*
- * Check mode permission on inode pointer. Mode is READ, WRITE or EXEC.
- * The mode is shifted to select the owner/group/other fields. The
- * super user is granted all permissions.
- *
- * NB: Called from vnode op table. It seems this could all be done
- * using vattr's but...
- */
-iaccess(ip, mode, cred)
-       register struct inode *ip;
-       register int mode;
-       struct ucred *cred;
-{
-       register gid_t *gp;
-       register struct vnode *vp = ITOV(ip);
-       int i;
-
-       /*
-        * If you're the super-user,
-        * you always get access.
-        */
-       if (cred->cr_uid == 0)
-               return (0);
-       /*
-        * Access check is based on only one of owner, group, public.
-        * If not owner, then check group. If not a member of the
-        * group, then check public access.
-        */
-       if (cred->cr_uid != ip->i_uid) {
-               mode >>= 3;
-               gp = cred->cr_groups;
-               for (i = 0; i < cred->cr_ngroups; i++, gp++)
-                       if (ip->i_gid == *gp)
-                               goto found;
-               mode >>= 3;
-found:
-               ;
-       }
-       if ((ip->i_mode & mode) != 0)
-               return (0);
-       return (EACCES);
-}