Module Name: src
Committed By: riastradh
Date: Mon Mar 28 12:42:37 UTC 2022
Modified Files:
src/sys/dev/usb: ucom.c
Log Message:
ucom(4): Rework open/close/attach/detach logic.
- Defer sleep after hangup until open.
No need to make close hang; we just need to make sure some time has
passed before we next try to open.
This changes the wchan for the sleep. Oh well.
- Use .d_cfdriver/devtounit/cancel to resolve races between attach,
detach, open, close, and revoke.
- Use a separate .sc_closing flag instead of a UCOM_CLOSING state.
ucomcancel/ucomclose owns this flag, and it may be set in any state
(except UCOM_DEAD). UCOM_OPENING remains owned by ucomopen, which
might be interrupted by cancel/close.
- Rework error branches in ucomopen. Much simpler this way.
- Nix unnecessary reference counting.
To generate a diff of this commit:
cvs rdiff -u -r1.129 -r1.130 src/sys/dev/usb/ucom.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/usb/ucom.c
diff -u src/sys/dev/usb/ucom.c:1.129 src/sys/dev/usb/ucom.c:1.130
--- src/sys/dev/usb/ucom.c:1.129 Thu Jun 24 08:20:42 2021
+++ src/sys/dev/usb/ucom.c Mon Mar 28 12:42:37 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: ucom.c,v 1.129 2021/06/24 08:20:42 riastradh Exp $ */
+/* $NetBSD: ucom.c,v 1.130 2022/03/28 12:42:37 riastradh Exp $ */
/*
* Copyright (c) 1998, 2000 The NetBSD Foundation, Inc.
@@ -34,7 +34,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ucom.c,v 1.129 2021/06/24 08:20:42 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ucom.c,v 1.130 2022/03/28 12:42:37 riastradh Exp $");
#ifdef _KERNEL_OPT
#include "opt_usb.h"
@@ -180,11 +180,10 @@ struct ucom_softc {
UCOM_DEAD,
UCOM_ATTACHED,
UCOM_OPENING,
- UCOM_CLOSING,
UCOM_OPEN
} sc_state;
- int sc_refcnt;
- bool sc_dying; /* disconnecting */
+ bool sc_closing; /* software is closing */
+ bool sc_dying; /* hardware is gone */
struct pps_state sc_pps_state; /* pps state */
@@ -192,10 +191,12 @@ struct ucom_softc {
kmutex_t sc_lock;
kcondvar_t sc_statecv;
- kcondvar_t sc_detachcv;
+
+ struct timeval sc_hup_time;
};
dev_type_open(ucomopen);
+dev_type_cancel(ucomcancel);
dev_type_close(ucomclose);
dev_type_read(ucomread);
dev_type_write(ucomwrite);
@@ -206,6 +207,7 @@ dev_type_poll(ucompoll);
const struct cdevsw ucom_cdevsw = {
.d_open = ucomopen,
+ .d_cancel = ucomcancel,
.d_close = ucomclose,
.d_read = ucomread,
.d_write = ucomwrite,
@@ -216,16 +218,16 @@ const struct cdevsw ucom_cdevsw = {
.d_mmap = nommap,
.d_kqfilter = ttykqfilter,
.d_discard = nodiscard,
+ .d_cfdriver = &ucom_cd,
+ .d_devtounit = dev_minor_unit,
.d_flag = D_TTY | D_MPSAFE
};
-static void ucom_cleanup(struct ucom_softc *);
+static void ucom_cleanup(struct ucom_softc *, int);
static int ucomparam(struct tty *, struct termios *);
static int ucomhwiflow(struct tty *, int);
static void ucomstart(struct tty *);
static void ucom_shutdown(struct ucom_softc *);
-static int ucom_do_ioctl(struct ucom_softc *, u_long, void *,
- int, struct lwp *);
static void ucom_dtr(struct ucom_softc *, int);
static void ucom_rts(struct ucom_softc *, int);
static void ucom_break(struct ucom_softc *, int);
@@ -288,14 +290,13 @@ ucom_attach(device_t parent, device_t se
sc->sc_mcr = 0;
sc->sc_tx_stopped = 0;
sc->sc_swflags = 0;
- sc->sc_refcnt = 0;
+ sc->sc_closing = false;
sc->sc_dying = false;
sc->sc_state = UCOM_DEAD;
sc->sc_si = softint_establish(SOFTINT_USB, ucom_softintr, sc);
mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_SOFTUSB);
cv_init(&sc->sc_statecv, "ucomstate");
- cv_init(&sc->sc_detachcv, "ucomdtch");
SIMPLEQ_INIT(&sc->sc_ibuff_empty);
SIMPLEQ_INIT(&sc->sc_ibuff_full);
@@ -366,7 +367,6 @@ ucom_attach(device_t parent, device_t se
aprint_error_dev(self, "couldn't establish power handler\n");
sc->sc_state = UCOM_ATTACHED;
-
return;
fail_2:
@@ -375,8 +375,8 @@ fail_2:
if (ub->ub_xfer)
usbd_destroy_xfer(ub->ub_xfer);
}
-
usbd_close_pipe(sc->sc_bulkout_pipe);
+ sc->sc_bulkout_pipe = NULL;
fail_1:
for (ub = &sc->sc_ibuff[0]; ub != &sc->sc_ibuff[UCOM_IN_BUFFS];
@@ -385,11 +385,10 @@ fail_1:
usbd_destroy_xfer(ub->ub_xfer);
}
usbd_close_pipe(sc->sc_bulkin_pipe);
+ sc->sc_bulkin_pipe = NULL;
fail_0:
aprint_error_dev(self, "attach failed, error=%d\n", error);
-
- return;
}
int
@@ -406,49 +405,21 @@ ucom_detach(device_t self, int flags)
(uintptr_t)tp, 0);
DPRINTF("... pipe=%jd,%jd", sc->sc_bulkin_no, sc->sc_bulkout_no, 0, 0);
+ /* Prevent new opens from hanging. */
mutex_enter(&sc->sc_lock);
sc->sc_dying = true;
mutex_exit(&sc->sc_lock);
pmf_device_deregister(self);
- if (sc->sc_bulkin_pipe != NULL) {
- usbd_abort_pipe(sc->sc_bulkin_pipe);
- }
- if (sc->sc_bulkout_pipe != NULL) {
- usbd_abort_pipe(sc->sc_bulkout_pipe);
- }
-
- mutex_enter(&sc->sc_lock);
-
- /* wait for open/close to finish */
- while (sc->sc_state == UCOM_OPENING || sc->sc_state == UCOM_CLOSING) {
- int error = cv_wait_sig(&sc->sc_statecv, &sc->sc_lock);
-
- if (error) {
- mutex_exit(&sc->sc_lock);
- return error;
- }
- }
-
- sc->sc_refcnt--;
- while (sc->sc_refcnt >= 0) {
- /* Wake up anyone waiting */
- if (tp != NULL) {
- mutex_spin_enter(&tty_lock);
- CLR(tp->t_state, TS_CARR_ON);
- CLR(tp->t_cflag, CLOCAL | MDMBUF);
- ttyflush(tp, FREAD|FWRITE);
- mutex_spin_exit(&tty_lock);
- }
- /* Wait for processes to go away. */
- if (cv_timedwait(&sc->sc_detachcv, &sc->sc_lock, hz * 60))
- aprint_error_dev(self, ": didn't detach\n");
+ /* tty is now off. */
+ if (tp != NULL) {
+ mutex_spin_enter(&tty_lock);
+ CLR(tp->t_state, TS_CARR_ON);
+ CLR(tp->t_cflag, CLOCAL | MDMBUF);
+ mutex_spin_exit(&tty_lock);
}
- softint_disestablish(sc->sc_si);
- mutex_exit(&sc->sc_lock);
-
/* locate the major number */
maj = cdevsw_lookup_major(&ucom_cdevsw);
@@ -459,6 +430,8 @@ ucom_detach(device_t self, int flags)
vdevgone(maj, mn | UCOMDIALOUT_MASK, mn | UCOMDIALOUT_MASK, VCHR);
vdevgone(maj, mn | UCOMCALLUNIT_MASK, mn | UCOMCALLUNIT_MASK, VCHR);
+ softint_disestablish(sc->sc_si);
+
/* Detach and free the tty. */
if (tp != NULL) {
tty_detach(tp);
@@ -491,7 +464,6 @@ ucom_detach(device_t self, int flags)
mutex_destroy(&sc->sc_lock);
cv_destroy(&sc->sc_statecv);
- cv_destroy(&sc->sc_detachcv);
return 0;
}
@@ -509,11 +481,23 @@ ucom_shutdown(struct ucom_softc *sc)
*/
if (ISSET(tp->t_cflag, HUPCL)) {
ucom_dtr(sc, 0);
- /* XXX will only timeout */
- (void) kpause(ttclos, false, hz, NULL);
+ mutex_enter(&sc->sc_lock);
+ microuptime(&sc->sc_hup_time);
+ sc->sc_hup_time.tv_sec++;
+ mutex_exit(&sc->sc_lock);
}
}
+/*
+ * ucomopen(dev, flag, mode, l)
+ *
+ * Called when anyone tries to open /dev/ttyU? for an existing
+ * ucom? instance that has completed attach. The attach may have
+ * failed, though, or there may be concurrent detach or close in
+ * progress, so fail if attach failed (no sc_tty) or detach has
+ * begun (sc_dying), or wait if there's a concurrent close in
+ * progress before reopening.
+ */
int
ucomopen(dev_t dev, int flag, int mode, struct lwp *l)
{
@@ -523,14 +507,11 @@ ucomopen(dev_t dev, int flag, int mode,
UCOMHIST_FUNC(); UCOMHIST_CALLED();
- if (sc == NULL)
- return ENXIO;
-
mutex_enter(&sc->sc_lock);
if (sc->sc_dying) {
DPRINTF("... dying", 0, 0, 0, 0);
mutex_exit(&sc->sc_lock);
- return EIO;
+ return ENXIO;
}
if (!device_is_active(sc->sc_dev)) {
@@ -539,6 +520,11 @@ ucomopen(dev_t dev, int flag, int mode,
}
struct tty *tp = sc->sc_tty;
+ if (tp == NULL) {
+ DPRINTF("... not attached", 0, 0, 0, 0);
+ mutex_exit(&sc->sc_lock);
+ return ENXIO;
+ }
DPRINTF("unit=%jd, tp=%#jx", unit, (uintptr_t)tp, 0, 0);
@@ -548,40 +534,64 @@ ucomopen(dev_t dev, int flag, int mode,
}
/*
- * Wait while the device is initialized by the
- * first opener or cleaned up by the last closer.
+ * If the previous use had set DTR on close, wait up to one
+ * second for the other side to notice we hung up. After
+ * sleeping, the tty may have been revoked, so restart the
+ * whole operation.
+ *
+ * XXX The wchan is not ttclose but maybe should be.
*/
- while (sc->sc_state == UCOM_OPENING || sc->sc_state == UCOM_CLOSING) {
- error = cv_wait_sig(&sc->sc_statecv, &sc->sc_lock);
-
- if (sc->sc_dying)
- error = EIO;
-
- if (error) {
+ if (timerisset(&sc->sc_hup_time)) {
+ struct timeval now, delta;
+ int ms, ticks;
+
+ microuptime(&now);
+ if (timercmp(&now, &sc->sc_hup_time, <)) {
+ timersub(&sc->sc_hup_time, &now, &delta);
+ ms = MIN(INT_MAX - 1000, delta.tv_sec*1000);
+ ms += howmany(delta.tv_usec, 1000);
+ ticks = MAX(1, MIN(INT_MAX, mstohz(ms)));
+ error = cv_timedwait_sig(&sc->sc_statecv, &sc->sc_lock,
+ ticks);
mutex_exit(&sc->sc_lock);
- return error;
+ return error ? error : ERESTART;
}
}
- enum ucom_state state = sc->sc_state;
+ /*
+ * Wait while the device is initialized by the
+ * first opener or cleaned up by the last closer.
+ */
+ enum ucom_state state = sc->sc_state;
+ if (state == UCOM_OPENING || sc->sc_closing) {
+ if (flag & FNONBLOCK)
+ error = EWOULDBLOCK;
+ else
+ error = cv_wait_sig(&sc->sc_statecv, &sc->sc_lock);
+ mutex_exit(&sc->sc_lock);
+ return error ? error : ERESTART;
+ }
KASSERTMSG(state == UCOM_OPEN || state == UCOM_ATTACHED,
"state is %d", state);
- bool cleanup = false;
- /* If this is the first open then perform the initialisation */
- if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
- KASSERT(state == UCOM_ATTACHED);
+ /*
+ * If this is the first open, then make sure the pipes are
+ * running and perform any initialization needed.
+ */
+ bool firstopen = (state == UCOM_ATTACHED);
+ if (firstopen) {
+ KASSERT(!ISSET(tp->t_state, TS_ISOPEN));
+ KASSERT(tp->t_wopen == 0);
+
tp->t_dev = dev;
- cleanup = true;
sc->sc_state = UCOM_OPENING;
-
mutex_exit(&sc->sc_lock);
+
if (sc->sc_methods->ucom_open != NULL) {
error = sc->sc_methods->ucom_open(sc->sc_parent,
sc->sc_portno);
- if (error) {
- goto fail_2;
- }
+ if (error)
+ goto bad;
}
ucom_status_change(sc);
@@ -628,12 +638,6 @@ ucomopen(dev_t dev, int flag, int mode,
ucom_rts(sc, 1);
mutex_enter(&sc->sc_lock);
- if (sc->sc_dying) {
- DPRINTF("... dying", 0, 0, 0, 0);
- error = EIO;
- goto fail_1;
- }
-
sc->sc_rx_unblock = 0;
sc->sc_rx_stopped = 0;
sc->sc_tx_stopped = 0;
@@ -643,12 +647,10 @@ ucomopen(dev_t dev, int flag, int mode,
error = ucomsubmitread(sc, ub);
if (error) {
mutex_exit(&sc->sc_lock);
- goto fail_2;
+ goto bad;
}
}
}
- sc->sc_state = UCOM_OPEN;
- cv_signal(&sc->sc_statecv);
mutex_exit(&sc->sc_lock);
DPRINTF("unit=%jd, tp=%#jx dialout %jd nonblock %jd", unit,
@@ -661,99 +663,152 @@ ucomopen(dev_t dev, int flag, int mode,
if (error)
goto bad;
+ /*
+ * Success! If this was the first open, notify waiters that
+ * the tty is open for business.
+ */
+ if (firstopen) {
+ mutex_enter(&sc->sc_lock);
+ KASSERT(sc->sc_state == UCOM_OPENING);
+ sc->sc_state = UCOM_OPEN;
+ cv_broadcast(&sc->sc_statecv);
+ mutex_exit(&sc->sc_lock);
+ }
return 0;
bad:
- cleanup = !ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0;
+ /*
+ * Failure! If this was the first open, hang up, abort pipes,
+ * and notify waiters that we're not opening after all.
+ */
+ if (firstopen) {
+ ucom_cleanup(sc, flag);
-fail_2:
- if (cleanup) {
- /*
- * We failed to open the device, and nobody else had
- * it opened. Clean up the state as appropriate.
- */
- ucom_cleanup(sc);
+ mutex_enter(&sc->sc_lock);
+ KASSERT(sc->sc_state == UCOM_OPENING);
+ sc->sc_state = UCOM_ATTACHED;
+ cv_broadcast(&sc->sc_statecv);
+ mutex_exit(&sc->sc_lock);
}
-
- mutex_enter(&sc->sc_lock);
-
-fail_1:
- sc->sc_state = state;
- cv_signal(&sc->sc_statecv);
- mutex_exit(&sc->sc_lock);
-
return error;
}
+/*
+ * ucomcancel(dev, flag, mode, l)
+ *
+ * Called on revoke or last close. Must interrupt any pending I/O
+ * operations and make them fail promptly; once they have all
+ * finished (except possibly new opens), ucomclose will be called.
+ * We set sc_closing to block new opens until ucomclose runs.
+ */
int
-ucomclose(dev_t dev, int flag, int mode, struct lwp *l)
+ucomcancel(dev_t dev, int flag, int mode, struct lwp *l)
{
const int unit = UCOMUNIT(dev);
struct ucom_softc *sc = device_lookup_private(&ucom_cd, unit);
- int error = 0;
UCOMHIST_FUNC(); UCOMHIST_CALLED();
DPRINTF("unit=%jd", UCOMUNIT(dev), 0, 0, 0);
+ /*
+ * This can run at any time before ucomclose on any device
+ * node, even if never attached or if attach failed, so we may
+ * not have a softc or a tty.
+ */
if (sc == NULL)
return 0;
+ struct tty *tp = sc->sc_tty;
+ if (tp == NULL)
+ return 0;
+ /*
+ * Mark the device closing so opens block until we're done
+ * closing. Wake them up so they start over at the top -- if
+ * we're closing because we're detaching, they need to wake up
+ * and notice it's time to fail.
+ */
mutex_enter(&sc->sc_lock);
- if (sc->sc_dying) {
- DPRINTF("... dying", 0, 0, 0, 0);
- mutex_exit(&sc->sc_lock);
- return ENXIO;
- }
+ sc->sc_closing = true;
+ cv_broadcast(&sc->sc_statecv);
+ mutex_exit(&sc->sc_lock);
/*
- * Wait until any opens/closes have finished
+ * Cancel any pending tty I/O operations, causing them to wake
+ * up and fail promptly, and preventing any new ones from
+ * starting to wait until we have finished closing.
*/
- while (sc->sc_state == UCOM_OPENING || sc->sc_state == UCOM_CLOSING) {
- error = cv_wait_sig(&sc->sc_statecv, &sc->sc_lock);
+ ttycancel(tp);
- if (sc->sc_dying)
- error = EIO;
+ return 0;
+}
- if (error) {
- mutex_exit(&sc->sc_lock);
- return error;
- }
- }
+/*
+ * ucomclose(dev, flag, mode, l)
+ *
+ * Called after ucomcancel, when all prior operations on the /dev
+ * node have completed. Only new opens may be in progress at this
+ * point, but they will block until sc_closing is set to false.
+ */
+int
+ucomclose(dev_t dev, int flag, int mode, struct lwp *l)
+{
+ const int unit = UCOMUNIT(dev);
+ struct ucom_softc *sc = device_lookup_private(&ucom_cd, unit);
+ int error = 0;
- struct tty *tp = sc->sc_tty;
+ UCOMHIST_FUNC(); UCOMHIST_CALLED();
- if (!ISSET(tp->t_state, TS_ISOPEN)) {
- KASSERT(sc->sc_state == UCOM_ATTACHED);
- mutex_exit(&sc->sc_lock);
+ DPRINTF("unit=%jd", UCOMUNIT(dev), 0, 0, 0);
+
+ /*
+ * This can run at any time after ucomcancel on any device
+ * node, even if never attached or if attach failed, so we may
+ * not have a softc or a tty.
+ */
+ if (sc == NULL)
+ return 0;
+ struct tty *tp = sc->sc_tty;
+ if (tp == NULL)
return 0;
- }
- KASSERT(sc->sc_state == UCOM_OPEN);
- sc->sc_state = UCOM_CLOSING;
- mutex_exit(&sc->sc_lock);
+ /*
+ * Close the tty, causing anyone waiting for it to wake, and
+ * hang up the phone.
+ */
+ ucom_cleanup(sc, flag);
- (*tp->t_linesw->l_close)(tp, flag);
- ttyclose(tp);
+ /*
+ * ttyclose should have cleared TS_ISOPEN and interrupted all
+ * pending opens, which should have completed by now.
+ */
+ mutex_spin_enter(&tty_lock);
+ KASSERT(!ISSET(tp->t_state, TS_ISOPEN));
+ KASSERT(tp->t_wopen == 0);
+ mutex_spin_exit(&tty_lock);
- /* state when we're done - default to open */
- enum ucom_state state = UCOM_OPEN;
- if (!ISSET(tp->t_state, TS_ISOPEN) && tp->t_wopen == 0) {
- /*
- * Although we got a last close, the device may still be in
- * use; e.g. if this was the dialout node, and there are still
- * processes waiting for carrier on the non-dialout node.
- */
- ucom_cleanup(sc);
- if (sc->sc_methods->ucom_close != NULL)
- sc->sc_methods->ucom_close(sc->sc_parent,
- sc->sc_portno);
- state = UCOM_ATTACHED;
+ /*
+ * Close any device-specific state.
+ */
+ if (sc->sc_methods->ucom_close != NULL) {
+ sc->sc_methods->ucom_close(sc->sc_parent,
+ sc->sc_portno);
}
+ /*
+ * We're now closed. Can reopen after this point, so resume
+ * transfers, mark us no longer closing, and notify anyone
+ * waiting in open. The state may be OPEN or ATTACHED at this
+ * point -- OPEN if the device was already open when we closed
+ * it, ATTACHED if we interrupted it in the process of opening.
+ */
mutex_enter(&sc->sc_lock);
- sc->sc_state = state;
- cv_signal(&sc->sc_statecv);
+ KASSERTMSG(sc->sc_state == UCOM_ATTACHED || sc->sc_state == UCOM_OPEN,
+ "%s sc=%p state=%d", device_xname(sc->sc_dev), sc, sc->sc_state);
+ KASSERT(sc->sc_closing);
+ sc->sc_state = UCOM_ATTACHED;
+ sc->sc_closing = false;
+ cv_broadcast(&sc->sc_statecv);
mutex_exit(&sc->sc_lock);
return error;
@@ -764,34 +819,11 @@ ucomread(dev_t dev, struct uio *uio, int
{
const int unit = UCOMUNIT(dev);
struct ucom_softc * const sc = device_lookup_private(&ucom_cd, unit);
- int error;
-
- UCOMHIST_FUNC(); UCOMHIST_CALLED();
-
- if (sc == NULL)
- return EIO;
-
- mutex_enter(&sc->sc_lock);
- if (sc->sc_dying) {
- DPRINTF("... dying", 0, 0, 0, 0);
- mutex_exit(&sc->sc_lock);
- return EIO;
- }
-
struct tty *tp = sc->sc_tty;
- sc->sc_refcnt++;
- mutex_exit(&sc->sc_lock);
-
- error = ((*tp->t_linesw->l_read)(tp, uio, flag));
-
- mutex_enter(&sc->sc_lock);
- if (--sc->sc_refcnt < 0)
- cv_broadcast(&sc->sc_detachcv);
- DPRINTF("unit=%jd refcnt %jd", UCOMUNIT(dev), sc->sc_refcnt, 0, 0);
- mutex_exit(&sc->sc_lock);
+ UCOMHIST_FUNC(); UCOMHIST_CALLED();
- return error;
+ return (*tp->t_linesw->l_read)(tp, uio, flag);
}
int
@@ -799,34 +831,11 @@ ucomwrite(dev_t dev, struct uio *uio, in
{
const int unit = UCOMUNIT(dev);
struct ucom_softc * const sc = device_lookup_private(&ucom_cd, unit);
- int error;
-
- UCOMHIST_FUNC(); UCOMHIST_CALLED();
-
- if (sc == NULL)
- return EIO;
-
- mutex_enter(&sc->sc_lock);
- if (sc->sc_dying) {
- DPRINTF("... dying", 0, 0, 0, 0);
- mutex_exit(&sc->sc_lock);
- return EIO;
- }
-
struct tty *tp = sc->sc_tty;
- sc->sc_refcnt++;
- mutex_exit(&sc->sc_lock);
-
- error = ((*tp->t_linesw->l_write)(tp, uio, flag));
-
- mutex_enter(&sc->sc_lock);
- if (--sc->sc_refcnt < 0)
- cv_broadcast(&sc->sc_detachcv);
- DPRINTF("unit=%jd refcnt %jd", UCOMUNIT(dev), sc->sc_refcnt, 0, 0);
- mutex_exit(&sc->sc_lock);
+ UCOMHIST_FUNC(); UCOMHIST_CALLED();
- return error;
+ return (*tp->t_linesw->l_write)(tp, uio, flag);
}
int
@@ -834,32 +843,11 @@ ucompoll(dev_t dev, int events, struct l
{
const int unit = UCOMUNIT(dev);
struct ucom_softc * const sc = device_lookup_private(&ucom_cd, unit);
-
- UCOMHIST_FUNC(); UCOMHIST_CALLED();
-
- if (sc == NULL)
- return POLLHUP;
-
- mutex_enter(&sc->sc_lock);
- if (sc->sc_dying) {
- DPRINTF("... dying", 0, 0, 0, 0);
- mutex_exit(&sc->sc_lock);
- return POLLHUP;
- }
struct tty *tp = sc->sc_tty;
- sc->sc_refcnt++;
- mutex_exit(&sc->sc_lock);
-
- int revents = ((*tp->t_linesw->l_poll)(tp, events, l));
-
- mutex_enter(&sc->sc_lock);
- if (--sc->sc_refcnt < 0)
- cv_broadcast(&sc->sc_detachcv);
- DPRINTF("unit=%jd refcnt %jd", UCOMUNIT(dev), sc->sc_refcnt, 0, 0);
- mutex_exit(&sc->sc_lock);
+ UCOMHIST_FUNC(); UCOMHIST_CALLED();
- return revents;
+ return (*tp->t_linesw->l_poll)(tp, events, l);
}
struct tty *
@@ -868,7 +856,7 @@ ucomtty(dev_t dev)
const int unit = UCOMUNIT(dev);
struct ucom_softc * const sc = device_lookup_private(&ucom_cd, unit);
- return sc != NULL ? sc->sc_tty : NULL;
+ return sc->sc_tty;
}
int
@@ -876,38 +864,6 @@ ucomioctl(dev_t dev, u_long cmd, void *d
{
const int unit = UCOMUNIT(dev);
struct ucom_softc * const sc = device_lookup_private(&ucom_cd, unit);
- int error;
-
- UCOMHIST_FUNC(); UCOMHIST_CALLED();
-
- if (sc == NULL)
- return EIO;
-
- mutex_enter(&sc->sc_lock);
- if (sc->sc_dying) {
- DPRINTF("... dying", 0, 0, 0, 0);
- mutex_exit(&sc->sc_lock);
- return EIO;
- }
-
- sc->sc_refcnt++;
- mutex_exit(&sc->sc_lock);
-
- error = ucom_do_ioctl(sc, cmd, data, flag, l);
-
- mutex_enter(&sc->sc_lock);
- if (--sc->sc_refcnt < 0)
- cv_broadcast(&sc->sc_detachcv);
- DPRINTF("unit=%jd refcnt %jd", UCOMUNIT(dev), sc->sc_refcnt, 0, 0);
- mutex_exit(&sc->sc_lock);
-
- return error;
-}
-
-static int
-ucom_do_ioctl(struct ucom_softc *sc, u_long cmd, void *data, int flag,
- struct lwp *l)
-{
struct tty *tp = sc->sc_tty;
int error;
@@ -1147,20 +1103,9 @@ ucomparam(struct tty *tp, struct termios
struct ucom_softc * const sc = device_lookup_private(&ucom_cd, unit);
int error = 0;
- UCOMHIST_FUNC(); UCOMHIST_CALLED();
+ /* XXX should take tty lock around touching tp */
- if (sc == NULL)
- return EIO;
-
- mutex_enter(&sc->sc_lock);
- if (sc->sc_dying) {
- DPRINTF("... dying", 0, 0, 0, 0);
- mutex_exit(&sc->sc_lock);
- return EIO;
- }
-
- sc->sc_refcnt++;
- mutex_exit(&sc->sc_lock);
+ UCOMHIST_FUNC(); UCOMHIST_CALLED();
/* Check requested parameters. */
if (t->c_ispeed && t->c_ispeed != t->c_ospeed) {
@@ -1221,14 +1166,6 @@ XXX what if the hardware is not open
}
#endif
out:
- mutex_enter(&sc->sc_lock);
- if (--sc->sc_refcnt < 0)
- cv_broadcast(&sc->sc_detachcv);
- DPRINTF("unit=%jd refcnt %jd", UCOMUNIT(tp->t_dev), sc->sc_refcnt,
- 0, 0);
-
- mutex_exit(&sc->sc_lock);
-
return error;
}
@@ -1241,9 +1178,6 @@ ucomhwiflow(struct tty *tp, int block)
UCOMHIST_FUNC(); UCOMHIST_CALLED();
- if (sc == NULL)
- return 0;
-
KASSERT(&sc->sc_lock);
KASSERT(mutex_owned(&tty_lock));
@@ -1271,16 +1205,6 @@ ucomstart(struct tty *tp)
UCOMHIST_FUNC(); UCOMHIST_CALLED();
- if (sc == NULL)
- return;
-
- KASSERT(&sc->sc_lock);
- KASSERT(mutex_owned(&tty_lock));
- if (sc->sc_dying) {
- DPRINTF("... dying", 0, 0, 0, 0);
- return;
- }
-
if (ISSET(tp->t_state, TS_BUSY | TS_TIMEOUT | TS_TTSTOP))
goto out;
if (sc->sc_tx_stopped)
@@ -1387,7 +1311,7 @@ ucom_write_status(struct ucom_softc *sc,
mutex_spin_exit(&tty_lock);
if (err != USBD_CANCELLED && err != USBD_IOERROR &&
- !sc->sc_dying) {
+ !sc->sc_closing) {
if ((ub = SIMPLEQ_FIRST(&sc->sc_obuff_full)) != NULL)
ucom_submit_write(sc, ub);
@@ -1428,15 +1352,9 @@ ucom_softintr(void *arg)
UCOMHIST_FUNC(); UCOMHIST_CALLED();
struct ucom_softc *sc = arg;
+ struct tty *tp = sc->sc_tty;
mutex_enter(&sc->sc_lock);
- if (sc->sc_dying) {
- DPRINTF("... dying", 0, 0, 0, 0);
- mutex_exit(&sc->sc_lock);
- return;
- }
-
- struct tty *tp = sc->sc_tty;
mutex_enter(&tty_lock);
if (!ISSET(tp->t_state, TS_ISOPEN)) {
mutex_exit(&tty_lock);
@@ -1483,11 +1401,7 @@ ucom_read_complete(struct ucom_softc *sc
if (ub->ub_index == ub->ub_len) {
SIMPLEQ_REMOVE_HEAD(&sc->sc_ibuff_full, ub_link);
-
- sc->sc_refcnt--;
- /* increments sc_refcnt */
ucomsubmitread(sc, ub);
-
ub = SIMPLEQ_FIRST(&sc->sc_ibuff_full);
}
}
@@ -1511,8 +1425,6 @@ ucomsubmitread(struct ucom_softc *sc, st
return EIO;
}
- sc->sc_refcnt++;
-
SIMPLEQ_INSERT_TAIL(&sc->sc_ibuff_empty, ub, ub_link);
return 0;
@@ -1522,6 +1434,7 @@ static void
ucomreadcb(struct usbd_xfer *xfer, void *p, usbd_status status)
{
struct ucom_softc *sc = (struct ucom_softc *)p;
+ struct tty *tp = sc->sc_tty;
struct ucom_buffer *ub;
uint32_t cc;
u_char *cp;
@@ -1530,15 +1443,13 @@ ucomreadcb(struct usbd_xfer *xfer, void
mutex_enter(&sc->sc_lock);
- struct tty *tp = sc->sc_tty;
-
if (status == USBD_CANCELLED || status == USBD_IOERROR ||
- sc->sc_dying) {
+ sc->sc_closing) {
- DPRINTF("... done (status %jd dying %jd)", status, sc->sc_dying,
- 0, 0);
+ DPRINTF("... done (status %jd closing %jd)",
+ status, sc->sc_closing, 0, 0);
- if (status == USBD_IOERROR || sc->sc_dying) {
+ if (status == USBD_IOERROR || sc->sc_closing) {
/* Send something to wake upper layer */
(tp->t_linesw->l_rint)('\n', tp);
mutex_spin_enter(&tty_lock); /* XXX */
@@ -1546,12 +1457,7 @@ ucomreadcb(struct usbd_xfer *xfer, void
mutex_spin_exit(&tty_lock); /* XXX */
}
- if (--sc->sc_refcnt < 0)
- cv_broadcast(&sc->sc_detachcv);
- DPRINTF("unit=%jd refcnt %jd", UCOMUNIT(tp->t_dev),
- sc->sc_refcnt, 0, 0);
mutex_exit(&sc->sc_lock);
-
return;
}
@@ -1567,8 +1473,7 @@ ucomreadcb(struct usbd_xfer *xfer, void
}
DPRINTF("... done (status %jd)", status, 0, 0, 0);
- sc->sc_refcnt--;
- /* re-adds ub to sc_ibuff_empty and increments sc_refcnt */
+ /* re-adds ub to sc_ibuff_empty */
ucomsubmitread(sc, ub);
mutex_exit(&sc->sc_lock);
return;
@@ -1588,8 +1493,7 @@ ucomreadcb(struct usbd_xfer *xfer, void
if (sc->sc_state != UCOM_OPEN) {
/* Go around again - we're not quite ready */
- sc->sc_refcnt--;
- /* re-adds ub to sc_ibuff_empty and increments sc_refcnt */
+ /* re-adds ub to sc_ibuff_empty */
ucomsubmitread(sc, ub);
mutex_exit(&sc->sc_lock);
DPRINTF("... done (not open)", 0, 0, 0, 0);
@@ -1607,16 +1511,7 @@ ucomreadcb(struct usbd_xfer *xfer, void
ub->ub_len = cc;
mutex_enter(&sc->sc_lock);
- if (sc->sc_dying) {
- if (--sc->sc_refcnt < 0)
- cv_broadcast(&sc->sc_detachcv);
- mutex_exit(&sc->sc_lock);
- DPRINTF("... dying", 0, 0, 0, 0);
- return;
- }
-
SIMPLEQ_INSERT_TAIL(&sc->sc_ibuff_full, ub, ub_link);
-
ucom_read_complete(sc);
mutex_exit(&sc->sc_lock);
@@ -1624,33 +1519,34 @@ ucomreadcb(struct usbd_xfer *xfer, void
}
static void
-ucom_cleanup(struct ucom_softc *sc)
+ucom_cleanup(struct ucom_softc *sc, int flag)
{
+ struct tty *tp = sc->sc_tty;
UCOMHIST_FUNC(); UCOMHIST_CALLED();
- DPRINTF("aborting pipes", 0, 0, 0, 0);
+ DPRINTF("closing pipes", 0, 0, 0, 0);
- mutex_enter(&sc->sc_lock);
-
- /* If we're dying then the detach routine will abort our pipes, etc */
- if (sc->sc_dying) {
- DPRINTF("... dying", 0, 0, 0, 0);
-
- mutex_exit(&sc->sc_lock);
- return;
- }
+ /*
+ * Close the tty and interrupt any pending opens waiting for
+ * carrier so they restart or give up. This may flush data.
+ */
+ (*tp->t_linesw->l_close)(tp, flag);
+ ttyclose(tp);
- mutex_exit(&sc->sc_lock);
+ /*
+ * Interrupt any pending xfers and cause them to fail promptly.
+ * New xfers will only be submitted under the lock after
+ * sc_closing is cleared.
+ */
+ usbd_abort_pipe(sc->sc_bulkin_pipe);
+ usbd_abort_pipe(sc->sc_bulkout_pipe);
+ /*
+ * Hang up the phone and start the timer before we can make a
+ * call again, if necessary.
+ */
ucom_shutdown(sc);
-
- if (sc->sc_bulkin_pipe != NULL) {
- usbd_abort_pipe(sc->sc_bulkin_pipe);
- }
- if (sc->sc_bulkout_pipe != NULL) {
- usbd_abort_pipe(sc->sc_bulkout_pipe);
- }
}
#endif /* NUCOM > 0 */
