[PATCH] s390: ctc driver changes

From: Peter Tiedemann <ptiedem@de.ibm.com>

ctc driver changes:
 - Make use of the debug feature to ease debugging.
 - ctctty: use dev_alloc_name to allocate a network device name.
 - ctctty: avoid deadlock of ctc_tty_close vs ctc_tty_flush_buffer.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/s390/net/Makefile

@@ -2,7 +2,7 @@
 # S/390 network devices
 #
 
-ctc-objs := ctcmain.o ctctty.o
+ctc-objs := ctcmain.o ctctty.o ctcdbug.o
 
 obj-$(CONFIG_IUCV) += iucv.o
 obj-$(CONFIG_NETIUCV) += netiucv.o fsm.o

drivers/s390/net/ctcdbug.c

+/*
+ *
+ * linux/drivers/s390/net/ctcdbug.c ($Revision: 1.1 $)
+ *
+ * Linux on zSeries OSA Express and HiperSockets support
+ *
+ * Copyright 2000,2003 IBM Corporation
+ *
+ *    Author(s): Original Code written by
+ *			  Peter Tiedemann (ptiedem@de.ibm.com)
+ *
+ *    $Revision: 1.1 $	 $Date: 2004/07/02 16:31:22 $
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "ctcdbug.h"
+
+/**
+ * Debug Facility Stuff
+ */
+debug_info_t *dbf_setup = NULL;
+debug_info_t *dbf_data = NULL;
+debug_info_t *dbf_trace = NULL;
+
+DEFINE_PER_CPU(char[256], dbf_txt_buf);
+
+void
+unregister_dbf_views(void)
+{
+	if (dbf_setup)
+		debug_unregister(dbf_setup);
+	if (dbf_data)
+		debug_unregister(dbf_data);
+	if (dbf_trace)
+		debug_unregister(dbf_trace);
+}
+int
+register_dbf_views(void)
+{
+	dbf_setup = debug_register(CTC_DBF_SETUP_NAME,
+					CTC_DBF_SETUP_INDEX,
+					CTC_DBF_SETUP_NR_AREAS,
+					CTC_DBF_SETUP_LEN);
+	dbf_data = debug_register(CTC_DBF_DATA_NAME,
+				       CTC_DBF_DATA_INDEX,
+				       CTC_DBF_DATA_NR_AREAS,
+				       CTC_DBF_DATA_LEN);
+	dbf_trace = debug_register(CTC_DBF_TRACE_NAME,
+					CTC_DBF_TRACE_INDEX,
+					CTC_DBF_TRACE_NR_AREAS,
+					CTC_DBF_TRACE_LEN);
+
+	if ((dbf_setup == NULL) || (dbf_data == NULL) ||
+	    (dbf_trace == NULL)) {
+		unregister_dbf_views();
+		return -ENOMEM;
+	}
+	debug_register_view(dbf_setup, &debug_hex_ascii_view);
+	debug_set_level(dbf_setup, CTC_DBF_SETUP_LEVEL);
+
+	debug_register_view(dbf_data, &debug_hex_ascii_view);
+	debug_set_level(dbf_data, CTC_DBF_DATA_LEVEL);
+
+	debug_register_view(dbf_trace, &debug_hex_ascii_view);
+	debug_set_level(dbf_trace, CTC_DBF_TRACE_LEVEL);
+
+	return 0;
+}
+
+

drivers/s390/net/ctcdbug.h

+/*
+ *
+ * linux/drivers/s390/net/ctcdbug.h ($Revision: 1.1 $)
+ *
+ * Linux on zSeries OSA Express and HiperSockets support
+ *
+ * Copyright 2000,2003 IBM Corporation
+ *
+ *    Author(s): Original Code written by
+ *			  Peter Tiedemann (ptiedem@de.ibm.com)
+ *
+ *    $Revision: 1.1 $	 $Date: 2004/07/02 16:31:22 $
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+
+#include <asm/debug.h>
+/**
+ * Debug Facility stuff
+ */
+#define CTC_DBF_SETUP_NAME "ctc_setup"
+#define CTC_DBF_SETUP_LEN 16
+#define CTC_DBF_SETUP_INDEX 3
+#define CTC_DBF_SETUP_NR_AREAS 1
+#define CTC_DBF_SETUP_LEVEL 3
+
+#define CTC_DBF_DATA_NAME "ctc_data"
+#define CTC_DBF_DATA_LEN 128
+#define CTC_DBF_DATA_INDEX 3
+#define CTC_DBF_DATA_NR_AREAS 1
+#define CTC_DBF_DATA_LEVEL 2
+
+#define CTC_DBF_TRACE_NAME "ctc_trace"
+#define CTC_DBF_TRACE_LEN 16
+#define CTC_DBF_TRACE_INDEX 2
+#define CTC_DBF_TRACE_NR_AREAS 2
+#define CTC_DBF_TRACE_LEVEL 3
+
+#define DBF_TEXT(name,level,text) \
+	do { \
+		debug_text_event(dbf_##name,level,text); \
+	} while (0)
+
+#define DBF_HEX(name,level,addr,len) \
+	do { \
+		debug_event(dbf_##name,level,(void*)(addr),len); \
+	} while (0)
+
+extern DEFINE_PER_CPU(char[256], dbf_txt_buf);
+extern debug_info_t *dbf_setup;
+extern debug_info_t *dbf_data;
+extern debug_info_t *dbf_trace;
+
+
+#define DBF_TEXT_(name,level,text...)				\
+	do {								\
+		char* dbf_txt_buf = get_cpu_var(dbf_txt_buf);	\
+		sprintf(dbf_txt_buf, text);			  	\
+		debug_text_event(dbf_##name,level,dbf_txt_buf);	\
+		put_cpu_var(dbf_txt_buf);				\
+	} while (0)
+
+#define DBF_SPRINTF(name,level,text...) \
+	do { \
+		debug_sprintf_event(dbf_trace, level, ##text ); \
+		debug_sprintf_event(dbf_trace, level, text ); \
+	} while (0)
+
+
+int register_dbf_views(void);
+
+void unregister_dbf_views(void);
+
+/**
+ * some more debug stuff
+ */
+
+#define HEXDUMP16(importance,header,ptr) \
+PRINT_##importance(header "%02x %02x %02x %02x  %02x %02x %02x %02x  " \
+		   "%02x %02x %02x %02x  %02x %02x %02x %02x\n", \
+		   *(((char*)ptr)),*(((char*)ptr)+1),*(((char*)ptr)+2), \
+		   *(((char*)ptr)+3),*(((char*)ptr)+4),*(((char*)ptr)+5), \
+		   *(((char*)ptr)+6),*(((char*)ptr)+7),*(((char*)ptr)+8), \
+		   *(((char*)ptr)+9),*(((char*)ptr)+10),*(((char*)ptr)+11), \
+		   *(((char*)ptr)+12),*(((char*)ptr)+13), \
+		   *(((char*)ptr)+14),*(((char*)ptr)+15)); \
+PRINT_##importance(header "%02x %02x %02x %02x  %02x %02x %02x %02x  " \
+		   "%02x %02x %02x %02x  %02x %02x %02x %02x\n", \
+		   *(((char*)ptr)+16),*(((char*)ptr)+17), \
+		   *(((char*)ptr)+18),*(((char*)ptr)+19), \
+		   *(((char*)ptr)+20),*(((char*)ptr)+21), \
+		   *(((char*)ptr)+22),*(((char*)ptr)+23), \
+		   *(((char*)ptr)+24),*(((char*)ptr)+25), \
+		   *(((char*)ptr)+26),*(((char*)ptr)+27), \
+		   *(((char*)ptr)+28),*(((char*)ptr)+29), \
+		   *(((char*)ptr)+30),*(((char*)ptr)+31));
+
+static inline void
+hex_dump(unsigned char *buf, size_t len)
+{
+	size_t i;
+
+	for (i = 0; i < len; i++) {
+		if (i && !(i % 16))
+			printk("\n");
+		printk("%02x ", *(buf + i));
+	}
+	printk("\n");
+}
+

drivers/s390/net/ctctty.c

 /*
- * $Id: ctctty.c,v 1.17 2004/03/31 17:06:34 ptiedem Exp $
+ * $Id: ctctty.c,v 1.21 2004/07/02 16:31:22 ptiedem Exp $
  *
  * CTC / ESCON network driver, tty interface.
  *
@@ -30,6 +30,7 @@
 #include <asm/uaccess.h>
 #include <linux/devfs_fs_kernel.h>
 #include "ctctty.h"
+#include "ctcdbug.h"
 
 #define CTC_TTY_MAJOR       43
 #define CTC_TTY_MAX_DEVICES 64
@@ -103,6 +104,7 @@ ctc_tty_try_read(ctc_tty_info * info, struct sk_buff *skb)
 	int len;
 	struct tty_struct *tty;
 
+	DBF_TEXT(trace, 2, __FUNCTION__);
 	if ((tty = info->tty)) {
 		if (info->mcr & UART_MCR_RTS) {
 			c = TTY_FLIPBUF_SIZE - tty->flip.count;
@@ -132,6 +134,7 @@ ctc_tty_readmodem(ctc_tty_info *info)
 	int ret = 1;
 	struct tty_struct *tty;
 
+	DBF_TEXT(trace, 2, __FUNCTION__);
 	if ((tty = info->tty)) {
 		if (info->mcr & UART_MCR_RTS) {
 			int c = TTY_FLIPBUF_SIZE - tty->flip.count;
@@ -165,6 +168,7 @@ ctc_tty_setcarrier(struct net_device *netdev, int on)
 {
 	int i;
 
+	DBF_TEXT(trace, 2, __FUNCTION__);
 	if ((!driver) || ctc_tty_shuttingdown)
 		return;
 	for (i = 0; i < CTC_TTY_MAX_DEVICES; i++)
@@ -185,6 +189,7 @@ ctc_tty_netif_rx(struct sk_buff *skb)
 	int i;
 	ctc_tty_info *info = NULL;
 
+	DBF_TEXT(trace, 2, __FUNCTION__);
 	if (!skb)
 		return;
 	if ((!skb->dev) || (!driver) || ctc_tty_shuttingdown) {
@@ -249,6 +254,7 @@ ctc_tty_tint(ctc_tty_info * info)
 	int wake = 1;
 	int rc;
 
+	DBF_TEXT(trace, 2, __FUNCTION__);
 	if (!info->netdev) {
 		if (skb)
 			kfree_skb(skb);
@@ -341,6 +347,7 @@ ctc_tty_inject(ctc_tty_info *info, char c)
 	int skb_res;
 	struct sk_buff *skb;
 	
+	DBF_TEXT(trace, 2, __FUNCTION__);
 	if (ctc_tty_shuttingdown)
 		return;
 	skb_res = info->netdev->hard_header_len + sizeof(info->mcr) +
@@ -361,6 +368,7 @@ ctc_tty_inject(ctc_tty_info *info, char c)
 static void
 ctc_tty_transmit_status(ctc_tty_info *info)
 {
+	DBF_TEXT(trace, 2, __FUNCTION__);
 	if (ctc_tty_shuttingdown)
 		return;
 	info->flags |= CTC_ASYNC_TX_LINESTAT;
@@ -374,6 +382,7 @@ ctc_tty_change_speed(ctc_tty_info * info)
 	unsigned int quot;
 	int i;
 
+	DBF_TEXT(trace, 2, __FUNCTION__);
 	if (!info->tty || !info->tty->termios)
 		return;
 	cflag = info->tty->termios->c_cflag;
@@ -412,6 +421,7 @@ ctc_tty_change_speed(ctc_tty_info * info)
 static int
 ctc_tty_startup(ctc_tty_info * info)
 {
+	DBF_TEXT(trace, 2, __FUNCTION__);
 	if (info->flags & CTC_ASYNC_INITIALIZED)
 		return 0;
 #ifdef CTC_DEBUG_MODEM_OPEN
@@ -454,6 +464,7 @@ ctc_tty_stopdev(unsigned long data)
 static void
 ctc_tty_shutdown(ctc_tty_info * info)
 {
+	DBF_TEXT(trace, 2, __FUNCTION__);
 	if (!(info->flags & CTC_ASYNC_INITIALIZED))
 		return;
 #ifdef CTC_DEBUG_MODEM_OPEN
@@ -486,14 +497,17 @@ ctc_tty_write(struct tty_struct *tty, int from_user, const u_char * buf, int cou
 	int total = 0;
 	ctc_tty_info *info = (ctc_tty_info *) tty->driver_data;
 
+	DBF_TEXT(trace, 2, __FUNCTION__);
 	if (ctc_tty_shuttingdown)
-		return 0;
+		goto ex;
 	if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_write"))
-		return 0;
+		goto ex;
 	if (!tty)
-		return 0;
-	if (!info->netdev)
-		return -ENODEV;
+		goto ex;
+	if (!info->netdev) {
+		total = -ENODEV;
+		goto ex;
+	}
 	if (from_user)
 		down(&info->write_sem);
 	while (1) {
@@ -530,6 +544,8 @@ ctc_tty_write(struct tty_struct *tty, int from_user, const u_char * buf, int cou
 	}
 	if (from_user)
 		up(&info->write_sem);
+ex:
+	DBF_TEXT(trace, 6, __FUNCTION__);
 	return total;
 }
 
@@ -559,13 +575,14 @@ ctc_tty_flush_buffer(struct tty_struct *tty)
 	ctc_tty_info *info;
 	unsigned long flags;
 
+	DBF_TEXT(trace, 2, __FUNCTION__);
 	if (!tty)
-		return;
+		goto ex;
 	spin_lock_irqsave(&ctc_tty_lock, flags);
 	info = (ctc_tty_info *) tty->driver_data;
 	if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_flush_buffer")) {
 		spin_unlock_irqrestore(&ctc_tty_lock, flags);
-		return;
+		goto ex;
 	}
 	skb_queue_purge(&info->tx_queue);
 	info->lsr |= UART_LSR_TEMT;
@@ -574,6 +591,9 @@ ctc_tty_flush_buffer(struct tty_struct *tty)
 	if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
 	    tty->ldisc.write_wakeup)
 		(tty->ldisc.write_wakeup) (tty);
+ex:
+	DBF_TEXT_(trace, 2, "ex: %s ", __FUNCTION__);
+	return;
 }
 
 static void
@@ -783,7 +803,6 @@ ctc_tty_set_termios(struct tty_struct *tty, struct termios *old_termios)
 {
 	ctc_tty_info *info = (ctc_tty_info *) tty->driver_data;
 	unsigned int cflag = tty->termios->c_cflag;
-
 	ctc_tty_change_speed(info);
 
 	/* Handle transition to B0 */
@@ -1032,8 +1051,10 @@ ctc_tty_close(struct tty_struct *tty, struct file *filp)
 		}
 	}
 	ctc_tty_shutdown(info);
-	if (tty->driver->flush_buffer)
-		tty->driver->flush_buffer(tty);
+	if (tty->driver->flush_buffer) {
+		skb_queue_purge(&info->tx_queue);
+		info->lsr |= UART_LSR_TEMT;
+	}
 	if (tty->ldisc.flush_buffer)
 		tty->ldisc.flush_buffer(tty);
 	info->tty = 0;
@@ -1059,7 +1080,6 @@ ctc_tty_hangup(struct tty_struct *tty)
 {
 	ctc_tty_info *info = (ctc_tty_info *)tty->driver_data;
 	unsigned long saveflags;
-
 	if (ctc_tty_paranoia_check(info, tty->name, "ctc_tty_hangup"))
 		return;
 	ctc_tty_shutdown(info);
@@ -1185,6 +1205,21 @@ ctc_tty_register_netdev(struct net_device *dev) {
 		       "with NULL dev or NULL dev-name\n");
 		return -1;
 	}
+
+	/*
+	 *	If the name is a format string the caller wants us to
+	 *	do a name allocation : format string must end with %d
+	 */
+	if (strchr(dev->name, '%'))
+	{
+		int err = dev_alloc_name(dev, dev->name);	// dev->name is changed by this
+		if (err < 0) {
+			printk(KERN_DEBUG "dev_alloc returned error %d\n", err);
+			return err;
+		}
+
+	}
+
 	for (p = dev->name; p && ((*p < '0') || (*p > '9')); p++);
 	ttynum = simple_strtoul(p, &err, 0);
 	if ((ttynum < 0) || (ttynum >= CTC_TTY_MAX_DEVICES) ||