PNFSDS_COPYSIZ
dat = malloc(PNFSDS_COPYSIZ, M_TEMP, M_WAITOK);
nfsrv_zeropnfsdat = malloc(PNFSDS_COPYSIZ, M_TEMP,
ret = vn_rdwr(UIO_READ, fvp, dat, PNFSDS_COPYSIZ,
xfer = PNFSDS_COPYSIZ - aresid;
if (xfer < PNFSDS_COPYSIZ || rdpos ==
nfsrv_zeropnfsdat, PNFSDS_COPYSIZ) != 0)