From 34e2fb3bb655b79fc2b93e1ad69187508a91c479 Mon Sep 17 00:00:00 2001
From: thorpej <thorpej@NetBSD.org>
Date: Wed, 6 Nov 1996 03:02:59 +0000
Subject: [PATCH] Performance enhancement from Kirk McKusick
 <mckusick@McKusick.COM>: When freeing an indirect block, there is no need to
 write it (synchronously, no less!) before tossing it.

---
 sys/ufs/ffs/ffs_inode.c | 33 ++++++++++++++++++++-------------
 1 file changed, 20 insertions(+), 13 deletions(-)

diff --git a/sys/ufs/ffs/ffs_inode.c b/sys/ufs/ffs/ffs_inode.c
index 520625957f2d..1593e55e1777 100644
--- a/sys/ufs/ffs/ffs_inode.c
+++ b/sys/ufs/ffs/ffs_inode.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: ffs_inode.c,v 1.11 1996/09/01 23:49:21 mycroft Exp $	*/
+/*	$NetBSD: ffs_inode.c,v 1.12 1996/11/06 03:02:59 thorpej Exp $	*/
 
 /*
  * Copyright (c) 1982, 1986, 1989, 1993
@@ -397,7 +397,7 @@ ffs_indirtrunc(ip, lbn, dbn, lastbn, level, countp)
 	register struct fs *fs = ip->i_fs;
 	register daddr_t *bap;
 	struct vnode *vp;
-	daddr_t *copy, nb, nlbn, last;
+	daddr_t *copy = NULL, nb, nlbn, last;
 	long blkcount, factor;
 	int nblocks, blocksreleased = 0;
 	int error = 0, allerror = 0;
@@ -444,16 +444,16 @@ ffs_indirtrunc(ip, lbn, dbn, lastbn, level, countp)
 	}
 
 	bap = (daddr_t *)bp->b_data;
-	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;
-	bap = copy;
+	if (lastbn != -1) {
+		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));
+		error = bwrite(bp);
+		if (error)
+			allerror = error;
+		bap = copy;
+	}
 
 	/*
 	 * Recursively free totally unused blocks.
@@ -489,7 +489,14 @@ ffs_indirtrunc(ip, lbn, dbn, lastbn, level, countp)
 			blocksreleased += blkcount;
 		}
 	}
-	FREE(copy, M_TEMP);
+
+	if (copy != NULL) {
+		FREE(copy, M_TEMP);
+	} else {
+		bp->b_flags |= B_INVAL;
+		brelse(bp);
+	}
+
 	*countp = blocksreleased;
 	return (allerror);
 }