dahdi: Fix failure to read / write on kernel 3.16+

Kernel version 3.16+, since upstream commit (7f7f25e82d54870d "replace checking
for ->read/->aio_read presence with check in ->f_mode" )[1], does not like it
when dahdi changes the set of allowed file operations on a file descriptor
outside of the context of an open() system call.

DAHDI changes the available file operations when a channel is opened by first
opening /dev/dahdi/channel and then calling the DAHDI_SPECIFY ioctl to bind it
to a particular DAHDI channel. Until DAHDI_SPECIFY is called there weren't any
read()/write() callbacks implemented and therefore after the initial open, the
kernel was setting not setting FMODE_CAN_{WRITE,READ} on the file descriptor
indicating that those operations were not allowed.

Now define empty shell functions on the general dahdi_fops so the vfs layer will
not mark a file descriptor as unwritteable or unreadable on open.

[1] https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=7f7f25e82d54870df24d415a7007fbd327da027b

Internal-Issue-ID: DAHLIN-340
Reported-and-tested-by: Thomas B. Clark
Signed-off-by: Shaun Ruffell <sruffell@digium.com>
Signed-off-by: Russ Meyerriecks <rmeyerriecks@digium.com>

drivers/dahdi/dahdi-base.c

@@ -10284,6 +10284,18 @@ MODULE_PARM_DESC(auto_assign_spans,
 		 "channel numbers assigned by the driver. If 0, user space "
 		 "will need to assign them via /sys/bus/dahdi_devices.");
 
+
+static ssize_t dahdi_no_read(struct file *file, char __user *usrbuf,
+			     size_t count, loff_t *ppos)
+{
+	return -ENOSYS;
+}
+static ssize_t dahdi_no_write(struct file *file, const char __user *usrbuf,
+			      size_t count, loff_t *ppos)
+{
+	return -ENOSYS;
+}
+
 static const struct file_operations dahdi_fops = {
 	.owner   = THIS_MODULE,
 	.open    = dahdi_open,
@@ -10297,6 +10309,8 @@ static const struct file_operations dahdi_fops = {
 	.ioctl   = dahdi_ioctl,
 #endif
 	.poll    = dahdi_poll,
+	.read    = dahdi_no_read,
+	.write   = dahdi_no_write,
 };
 
 static const struct file_operations dahdi_timer_fops = {
@@ -10311,6 +10325,8 @@ static const struct file_operations dahdi_timer_fops = {
 	.ioctl   = dahdi_timer_ioctl,
 #endif
 	.poll    = dahdi_timer_poll,
+	.read    = dahdi_no_read,
+	.write   = dahdi_no_write,
 };
 
 /*

drivers/dahdi/dahdi_dynamic.c

@@ -201,7 +201,9 @@ static void dahdi_dynamic_sendmessage(struct dahdi_dynamic *d)
 static void __dahdi_dynamic_run(void)
 {
 	struct dahdi_dynamic *d;
+#ifdef ENABLE_TASKLETS
 	struct dahdi_dynamic_driver *drv;
+#endif
 
 	rcu_read_lock();
 	list_for_each_entry_rcu(d, &dspan_list, list) {
@@ -211,6 +213,13 @@ static void __dahdi_dynamic_run(void)
 	}
 
 #ifdef ENABLE_TASKLETS
+	list_for_each_entry_rcu(drv, &driver_list, list) {
+		/* Flush any traffic still pending in the driver */
+		if (drv->flush) {
+			drv->flush();
+		}
+	}
+#else
 	/* If tasklets are not enabled, the above section will be called in
 	 * interrupt context and the flushing of each driver will be called in a
 	 * separate tasklet that only handles that. This is necessary since some
@@ -221,13 +230,6 @@ static void __dahdi_dynamic_run(void)
 	 *
 	 */
 	tasklet_hi_schedule(&dahdi_dynamic_flush_tlet);
-#else
-	list_for_each_entry_rcu(drv, &driver_list, list) {
-		/* Flush any traffic still pending in the driver */
-		if (drv->flush) {
-			drv->flush();
-		}
-	}
 #endif
 	rcu_read_unlock();
 }

drivers/dahdi/datamods/hdlc_fr.c

@@ -1063,12 +1063,23 @@ static int fr_add_pvc(struct net_device *master, unsigned int dlci, int type)
 
 	used = pvc_is_used(pvc);
 
-	if (type == ARPHRD_ETHER)
+	if (type == ARPHRD_ETHER) {
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 17, 0)
+		dev = alloc_netdev(sizeof(struct net_device_stats),
+				   "pvceth%d", NET_NAME_UNKNOWN, ether_setup);
+#else
 		dev = alloc_netdev(sizeof(struct net_device_stats),
 				   "pvceth%d", ether_setup);
-	else
+#endif
+	} else {
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 17, 0)
+		dev = alloc_netdev(sizeof(struct net_device_stats),
+				   "pvc%d", NET_NAME_UNKNOWN, dlci_setup);
+#else
 		dev = alloc_netdev(sizeof(struct net_device_stats),
 				   "pvc%d", dlci_setup);
+#endif
+	}
 
 	if (!dev) {
 		printk(KERN_WARNING "%s: Memory squeeze on fr_pvc()\n",

drivers/dahdi/datamods/hdlc_generic.c

@@ -282,7 +282,12 @@ static void hdlc_setup(struct net_device *dev)
 struct net_device *alloc_hdlcdev(void *priv)
 {
 	struct net_device *dev;
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 17, 0)
+	dev = alloc_netdev(sizeof(hdlc_device), "hdlc%d",
+				NET_NAME_UNKNOWN, hdlc_setup);
+#else
 	dev = alloc_netdev(sizeof(hdlc_device), "hdlc%d", hdlc_setup);
+#endif
 	if (dev)
 		dev_to_hdlc(dev)->priv = priv;
 	return dev;

drivers/dahdi/firmware/Makefile

@@ -34,6 +34,7 @@ WCT820_VERSION:=1.76
 TE133_VERSION:=780019
 TE134_VERSION:=780017
 TE435_VERSION:=e0019
+TE436_VERSION:=10017
 A8A_VERSION:=1d0017
 A8B_VERSION:=1d0019
 A4A_VERSION:=a0017
@@ -43,7 +44,7 @@ FIRMWARE_URL:=http://downloads.digium.com/pub/telephony/firmware/releases
 
 ALL_FIRMWARE=FIRMWARE-OCT6114-032 FIRMWARE-OCT6114-064 FIRMWARE-OCT6114-128 FIRMWARE-OCT6114-256
 ALL_FIRMWARE+=FIRMWARE-TC400M FIRMWARE-HX8 FIRMWARE-VPMOCT032 FIRMWARE-TE820 FIRMWARE-TE133 FIRMWARE-TE134
-ALL_FIRMWARE+=FIRMWARE-A8A FIRMWARE-A8B FIRMWARE-A4A FIRMWARE-A4B FIRMWARE-TE435
+ALL_FIRMWARE+=FIRMWARE-A8A FIRMWARE-A8B FIRMWARE-A4A FIRMWARE-A4B FIRMWARE-TE435 FIRMWARE-TE436
 
 # Firmware files should use the naming convention: dahdi-fw-<base name>-<sub name>-<version> or dahdi-fw-<base name>-<version>
 # First example: dahdi-fw-oct6114-064-1.05.01
@@ -63,6 +64,7 @@ FIRMWARE:=$(FIRMWARE:FIRMWARE-TE820=dahdi-fw-te820-$(WCT820_VERSION).tar.gz)
 FIRMWARE:=$(FIRMWARE:FIRMWARE-TE133=dahdi-fw-te133-$(TE133_VERSION).tar.gz)
 FIRMWARE:=$(FIRMWARE:FIRMWARE-TE134=dahdi-fw-te134-$(TE134_VERSION).tar.gz)
 FIRMWARE:=$(FIRMWARE:FIRMWARE-TE435=dahdi-fw-te435-$(TE435_VERSION).tar.gz)
+FIRMWARE:=$(FIRMWARE:FIRMWARE-TE436=dahdi-fw-te436-$(TE436_VERSION).tar.gz)
 FIRMWARE:=$(FIRMWARE:FIRMWARE-A8A=dahdi-fw-a8b-$(A8B_VERSION).tar.gz)
 FIRMWARE:=$(FIRMWARE:FIRMWARE-A8B=dahdi-fw-a8a-$(A8A_VERSION).tar.gz)
 FIRMWARE:=$(FIRMWARE:FIRMWARE-A4A=dahdi-fw-a4b-$(A4B_VERSION).tar.gz)
@@ -138,6 +140,7 @@ hotplug-install: $(DESTDIR)/usr/lib/hotplug/firmware $(DESTDIR)/lib/firmware $(F
 	@$(call RUN_INST,dahdi-fw-te133,$(TE133_VERSION))
 	@$(call RUN_INST,dahdi-fw-te134,$(TE134_VERSION))
 	@$(call RUN_INST,dahdi-fw-te435,$(TE435_VERSION))
+	@$(call RUN_INST,dahdi-fw-te436,$(TE436_VERSION))
 	@$(call RUN_INST,dahdi-fw-a8a,$(A8A_VERSION))
 	@$(call RUN_INST,dahdi-fw-a8b,$(A8B_VERSION))
 	@$(call RUN_INST,dahdi-fw-a4a,$(A4A_VERSION))

drivers/dahdi/voicebus/voicebus_net.c

@@ -207,7 +207,13 @@ int vb_net_register(struct voicebus *vb, const char *board_name)
 	struct voicebus_netdev_priv *priv;
 	const char our_mac[] = { 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff};
 
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 17, 0)
+	netdev = alloc_netdev(sizeof(*priv), board_name,
+				NET_NAME_UNKNOWN, ether_setup);
+#else
 	netdev = alloc_netdev(sizeof(*priv), board_name, ether_setup);
+#endif
+
 	if (!netdev)
 		return -ENOMEM;
 	priv = netdev_priv(netdev);

drivers/dahdi/wctc4xxp/base.c

@@ -657,7 +657,13 @@ wctc4xxp_net_register(struct wcdte *wc)
 	struct wcdte_netdev_priv *priv;
 	const char our_mac[] = { 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff};
 
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 17, 0)
+	netdev = alloc_netdev(sizeof(*priv), wc->board_name,
+				NET_NAME_UNKNOWN, ether_setup);
+#else
 	netdev = alloc_netdev(sizeof(*priv), wc->board_name, ether_setup);
+#endif
+
 	if (!netdev)
 		return -ENOMEM;
 	priv = netdev_priv(netdev);

drivers/dahdi/wcte13xp-base.c

@@ -1316,6 +1316,10 @@ static int t13x_startup(struct file *file, struct dahdi_span *span)
 	/* Reset framer with proper parameters and start */
 	t13x_framer_start(wc);
 
+	/* Reset span alarm state to RED to prevent false
+	 * temporary GREEN state on span bringup */
+	span->alarms |= DAHDI_ALARM_RED;
+
 	/* Do we want to SYNC on receive or not. This must always happen after
 	 * the framer is fully reset. */
 	wcxb_set_clksrc(&wc->xb,

drivers/dahdi/wcte43x-base.c

@@ -65,7 +65,9 @@ static inline int delayed_work_pending(struct work_struct *work)
 #endif
 
 static const char *TE435_FW_FILENAME = "dahdi-fw-te435.bin";
+static const char *TE436_FW_FILENAME = "dahdi-fw-te436.bin";
 static const u32 TE435_VERSION = 0xe0019;
+static const u32 TE436_VERSION = 0x10017;
 
 /* #define RPC_RCLK */
 
@@ -794,6 +796,8 @@ struct t43x_desc {
 
 static const struct t43x_desc te435 = {"Wildcard TE435"}; /* pci express quad */
 static const struct t43x_desc te235 = {"Wildcard TE235"}; /* pci express dual */
+static const struct t43x_desc te436 = {"Wildcard TE436"}; /* pci quad */
+static const struct t43x_desc te236 = {"Wildcard TE236"}; /* pci dual */
 
 static int __t43x_pci_get(struct t43x *wc, unsigned int addr)
 {
@@ -1762,6 +1766,10 @@ static void t43x_framer_start(struct t43x *wc)
 		t43x_set_cas_mode(wc, unit);
 
 		set_bit(DAHDI_FLAGBIT_RUNNING, &ts->span.flags);
+
+		/* Reset span alarm state to RED to prevent false
+		 * temporary GREEN state on span bringup */
+		ts->span.alarms |= DAHDI_ALARM_RED;
 	}
 
 	for (unit = 0; unit < wc->numspans; unit++) {
@@ -3449,12 +3457,6 @@ static int __devinit t43x_init_one(struct pci_dev *pdev,
 		goto fail_exit;
 	}
 
-	/* Check for field updatable firmware */
-	res = wcxb_check_firmware(&wc->xb, TE435_VERSION,
-			TE435_FW_FILENAME, force_firmware, WCXB_RESET_NOW);
-	if (res)
-		goto fail_exit;
-
 	wc->ddev->hardware_id = t43x_read_serial(wc);
 
 	if (wc->ddev->hardware_id == NULL) {
@@ -3464,11 +3466,21 @@ static int __devinit t43x_init_one(struct pci_dev *pdev,
 	}
 
 	if (strncmp(wc->ddev->hardware_id, "1TE435F", 7) == 0) {
+		/* Quad-span PCIE */
 		wc->numspans = 4;
 		wc->devtype = &te435;
 	} else if (strncmp(wc->ddev->hardware_id, "1TE235F", 7) == 0) {
+		/* Dual-span PCIE */
 		wc->numspans = 2;
 		wc->devtype = &te235;
+	} else if (strncmp(wc->ddev->hardware_id, "1TE436F", 7) == 0) {
+		/* Quad-span PCI */
+		wc->numspans = 4;
+		wc->devtype = &te436;
+	} else if (strncmp(wc->ddev->hardware_id, "1TE236F", 7) == 0) {
+		/* Dual-span PCI */
+		wc->numspans = 2;
+		wc->devtype = &te236;
 	} else {
 		dev_info(&wc->xb.pdev->dev,
 			"Unable to identify board type from serial number %s\n",
@@ -3477,6 +3489,20 @@ static int __devinit t43x_init_one(struct pci_dev *pdev,
 		goto fail_exit;
 	}
 
+	/* Check for field updatable firmware */
+	if ((wc->devtype == &te435) || (wc->devtype == &te235)) {
+		res = wcxb_check_firmware(&wc->xb, TE435_VERSION,
+			TE435_FW_FILENAME, force_firmware, WCXB_RESET_NOW);
+	} else if ((wc->devtype == &te436) || (wc->devtype == &te236)) {
+		res = wcxb_check_firmware(&wc->xb, TE436_VERSION,
+			TE436_FW_FILENAME, force_firmware, WCXB_RESET_NOW);
+	} else {
+		res = -EIO;
+	}
+
+	if (res)
+		goto fail_exit;
+
 	for (x = 0; x < wc->numspans; x++) {
 		ts = kzalloc(sizeof(*wc->tspans[x]), GFP_KERNEL);
 		if (!ts) {
@@ -3595,6 +3621,7 @@ static void __devexit t43x_remove_one(struct pci_dev *pdev)
 
 static DEFINE_PCI_DEVICE_TABLE(t43x_pci_tbl) = {
 	{ 0xd161, 0x800e, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
+	{ 0xd161, 0x8013, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
 	{ 0 }
 };