--- src/sys/vfs/hammer/hammer_vfsops.c	2007/11/20 07:16:28	1.5
+++ src/sys/vfs/hammer/hammer_vfsops.c	2007/11/26 05:03:11	1.6
@@ -150,6 +150,12 @@ hammer_vfs_mount(struct mount *mp, char
 	mp->mnt_kern_flag |= MNTK_FSMID;
 	mp->mnt_stat.f_fsid.val[0] = 0;	/* XXX */
 	mp->mnt_stat.f_fsid.val[1] = 0;	/* XXX */
+
+	/* 
+	 * note: f_iosize is used by vnode_pager_haspage() when constructing
+	 * its VOP_BMAP call.
+	 */
+	mp->mnt_stat.f_iosize = HAMMER_BUFSIZE;
 	vfs_getnewfsid(mp);		/* XXX */
 	mp->mnt_maxsymlinklen = 255;
 	mp->mnt_flag |= MNT_LOCAL;