nvtruncbuf
int nvtruncbuf (struct vnode *vp, off_t length, int blksize, int boff,
error = nvtruncbuf(vp, nsize, biosize, -1, 0);
error = nvtruncbuf(vp, newsize, FUSE_BLKSIZE, -1, 0);
error = nvtruncbuf(vp, newsize, FUSE_BLKSIZE, -1, nvextflags);
nvtruncbuf(ip->vp, 0, HAMMER_BUFSIZE, 0, 0);
nvtruncbuf(ap->a_vp, vap->va_size,
nvtruncbuf(ap->a_vp, ip->ino_data.size,
nvtruncbuf(vp, 0, nblksize, 0, 0);
nvtruncbuf(ip->vp, nsize,
error = nvtruncbuf(vp, nsize, biosize, -1, flags);
error = nvtruncbuf(vp, newsize, node->tn_blksize,
allerror = nvtruncbuf(ovp, length, blkoffsize(fs, oip, length),
nvtruncbuf(vp, 0, nblksize, 0, 0);
nvtruncbuf(ip->vp, nsize,