[svn-commits] tzafrir: branch linux/tzafrir/sysfs r8767 - /linux/team/tzafrir/sysfs/drivers...

[SVN commits to the Digium repositories]

Author: tzafrir
Date: Mon Jun 14 15:49:49 2010
New Revision: 8767

URL: http://svnview.digium.com/svn/dahdi?view=rev&rev=8767
Log:
Safety against unplug/plug same PRI-AB

* Asterisk does not release D-Channel on removal events:
  - As a result, we cannot destroy those XPD's and XBUS's when unplugged.
  - On repluging, the XBUS identified as new AB and very bad things happen.
* The fix is to block dbus_activate() if we  have an XBUS with same LABEL.
* When asterisk is closed and the old, NOHW, AB is released, we can trigger
  the new AB activation via:
     echo start > /sys/bus/astribanks/devices/xbus-.../xbus_state

Modified:
    linux/team/tzafrir/sysfs/drivers/dahdi/xpp/card_global.c
    linux/team/tzafrir/sysfs/drivers/dahdi/xpp/xbus-core.c
    linux/team/tzafrir/sysfs/drivers/dahdi/xpp/xbus-core.h

Modified: linux/team/tzafrir/sysfs/drivers/dahdi/xpp/card_global.c
URL: http://svnview.digium.com/svn/dahdi/linux/team/tzafrir/sysfs/drivers/dahdi/xpp/card_global.c?view=diff&rev=8767&r1=8766&r2=8767
==============================================================================
--- linux/team/tzafrir/sysfs/drivers/dahdi/xpp/card_global.c (original)
+++ linux/team/tzafrir/sysfs/drivers/dahdi/xpp/card_global.c Mon Jun 14 15:49:49 2010
@@ -431,6 +431,8 @@
 		DBG(DEVICES, "NO XBUS\n");
 		return -EINVAL;
 	}
+	if (xbus_check_unique(xbus))
+		return -EBUSY;
 	XFRAME_NEW_CMD(xframe, pack, xbus, GLOBAL, AB_REQUEST, 0);
 	RPACKET_FIELD(pack, GLOBAL, AB_REQUEST, rev) = XPP_PROTOCOL_VERSION;
 	RPACKET_FIELD(pack, GLOBAL, AB_REQUEST, reserved) = 0;
@@ -610,6 +612,8 @@
 		goto proto_err;
 	}
 	XBUS_INFO(xbus, "DESCRIPTOR: %d cards, protocol revision %d\n", count_units, rev);
+	if (xbus_check_unique(xbus))
+		return -EBUSY;
 	xbus->revision = rev;
 	if(!worker) {
 		XBUS_ERR(xbus, "missing worker\n");

Modified: linux/team/tzafrir/sysfs/drivers/dahdi/xpp/xbus-core.c
URL: http://svnview.digium.com/svn/dahdi/linux/team/tzafrir/sysfs/drivers/dahdi/xpp/xbus-core.c?view=diff&rev=8767&r1=8766&r2=8767
==============================================================================
--- linux/team/tzafrir/sysfs/drivers/dahdi/xpp/xbus-core.c (original)
+++ linux/team/tzafrir/sysfs/drivers/dahdi/xpp/xbus-core.c Mon Jun 14 15:49:49 2010
@@ -80,6 +80,50 @@
 static struct xbus_desc {
 	xbus_t			*xbus;
 } xbuses_array[MAX_BUSES];
+
+static xbus_t *xbus_byhwid(const char *hwid)
+{
+	int	i;
+	xbus_t	*xbus;
+
+	for (i = 0; i < ARRAY_SIZE(xbuses_array); i++) {
+		xbus = xbuses_array[i].xbus;
+		if (xbus && strcmp(hwid, xbus->label) == 0)
+			return xbus;
+	}
+	return NULL;
+}
+
+
+/* If an Astribank disconnected and then reconnected, we prefer not to
+   fully initialize it
+ */
+int xbus_check_unique(xbus_t *xbus)
+{
+	xbus_t	*xbus_old;
+
+	if (!xbus)
+		return -ENOENT;
+	if (!xbus->label) {
+		XBUS_NOTICE(xbus, "Astribank without a Label: Bad.\n");
+		return 0;
+	}
+
+	XBUS_DBG(DEVICES, xbus, "Checking LABEL='%s'\n", xbus->label);
+	xbus_old = xbus_byhwid(xbus->label);
+	if (xbus_old && xbus_old != xbus) {
+		XBUS_NOTICE(xbus_old,
+			/* FIXME: rephrase message to hint this is a
+			   reconnecting AB */
+			"Duplicate LABEL='%s'. Leave %s unused. refcount_xbus=%d\n",
+			xbus_old->label,
+			xbus->busname,
+			refcount_xbus(xbus_old));
+		return -EBUSY;
+	}
+
+	return 0;
+}
 
 const char *xbus_statename(enum xbus_state st)
 {
@@ -1200,6 +1244,8 @@
 int xbus_activate(xbus_t *xbus)
 {
 	XBUS_INFO(xbus, "[%s] Activating\n", xbus->label);
+	if (xbus_check_unique(xbus))
+		return -EBUSY;
 	xpp_drift_init(xbus);
 	xbus_set_command_timer(xbus, 1);
 	xframe_queue_disable(&xbus->command_queue, 0);

Modified: linux/team/tzafrir/sysfs/drivers/dahdi/xpp/xbus-core.h
URL: http://svnview.digium.com/svn/dahdi/linux/team/tzafrir/sysfs/drivers/dahdi/xpp/xbus-core.h?view=diff&rev=8767&r1=8766&r2=8767
==============================================================================
--- linux/team/tzafrir/sysfs/drivers/dahdi/xpp/xbus-core.h (original)
+++ linux/team/tzafrir/sysfs/drivers/dahdi/xpp/xbus-core.h Mon Jun 14 15:49:49 2010
@@ -302,6 +302,7 @@
 
 xpd_t	*xpd_of(const xbus_t *xbus, int xpd_num);
 xpd_t	*xpd_byaddr(const xbus_t *xbus, uint unit, uint subunit);
+int	xbus_check_unique(xbus_t *xbus);
 bool	xbus_setstate(xbus_t *xbus, enum xbus_state newstate);
 bool	xbus_setflags(xbus_t *xbus, int flagbit, bool on);
 xbus_t	*xbus_new(struct xbus_ops *ops, ushort max_send_size, struct device *transport_device, void *priv);