diff options
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/net/switchctl.c | 48 |
1 files changed, 25 insertions, 23 deletions
diff --git a/sys/net/switchctl.c b/sys/net/switchctl.c index bd2ab2a38ae..7ac544b86bb 100644 --- a/sys/net/switchctl.c +++ b/sys/net/switchctl.c @@ -1,4 +1,4 @@ -/* $OpenBSD: switchctl.c,v 1.5 2016/11/08 19:11:57 rzalamena Exp $ */ +/* $OpenBSD: switchctl.c,v 1.6 2016/11/09 12:26:55 rzalamena Exp $ */ /* * Copyright (c) 2016 Kazuya GODA <goda@openbsd.org> @@ -125,23 +125,23 @@ int switchread(dev_t dev, struct uio *uio, int ioflag) { struct switch_softc *sc; - int error = 0, s, truncated; + struct mbuf *m; u_int len; - struct mbuf *m0, *m; + int s, error = 0; sc = switch_dev2sc(dev); if (sc == NULL) return (ENXIO); if (sc->sc_swdev->swdev_lastm != NULL) { - m0 = sc->sc_swdev->swdev_lastm; + m = sc->sc_swdev->swdev_lastm; sc->sc_swdev->swdev_lastm = NULL; goto skip_dequeue; } dequeue_next: s = splnet(); - while ((m0 = mq_dequeue(&sc->sc_swdev->swdev_outq)) == NULL) { + while ((m = mq_dequeue(&sc->sc_swdev->swdev_outq)) == NULL) { if (ISSET(ioflag, IO_NDELAY)) { error = EWOULDBLOCK; goto failed; @@ -160,32 +160,34 @@ switchread(dev_t dev, struct uio *uio, int ioflag) splx(s); skip_dequeue: - while (m0 != NULL && uio->uio_resid > 0 && error == 0) { - len = ulmin(uio->uio_resid, m0->m_len); - truncated = uio->uio_resid < m0->m_len; - if ((error = uiomove(mtod(m0, caddr_t), len, uio)) != 0) { + while (uio->uio_resid > 0) { + len = ulmin(uio->uio_resid, m->m_len); + if ((error = uiomove(mtod(m, caddr_t), len, uio)) != 0) { /* Save it so user can recover from EFAULT. */ - sc->sc_swdev->swdev_lastm = m0; + sc->sc_swdev->swdev_lastm = m; return (error); } - /* If we didn't finish moving, then save it for later. */ - if (truncated) { - m_adj(m0, len); - sc->sc_swdev->swdev_lastm = m0; - return (0); + /* Handle partial reads. */ + if (uio->uio_resid == 0) { + if (len < m->m_len) + m_adj(m, len); + else + m = m_free(m); + sc->sc_swdev->swdev_lastm = m; + break; } - m = m_free(m0); - m0 = m; + /* + * After consuming data from this mbuf test if we + * have to dequeue a new chain. + */ + m = m_free(m); + if (m == NULL) + goto dequeue_next; } - m_freem(m0); - - /* Keep reading if the user wants more. */ - if (uio->uio_resid > 0) - goto dequeue_next; - return (error); + return (0); failed: splx(s); return (error); |