1 files changed, 178 insertions, 110 deletions

diff --git a/drivers/s390/char/sclp_vt220.c b/drivers/s390/char/sclp_vt220.c
index ad51738c426..b9a9f721716 100644
--- a/drivers/s390/char/sclp_vt220.c
+++ b/drivers/s390/char/sclp_vt220.c
@@ -1,10 +1,9 @@
 /*
- *  drivers/s390/char/sclp_vt220.c
- *    SCLP VT220 terminal driver.
+ * SCLP VT220 terminal driver.
  *
- *  S390 version
- *    Copyright IBM Corp. 2003,2008
- *    Author(s): Peter Oberparleiter <Peter.Oberparleiter@de.ibm.com>
+ * Copyright IBM Corp. 2003, 2009
+ *
+ * Author(s): Peter Oberparleiter <Peter.Oberparleiter@de.ibm.com>
  */
 
 #include <linux/module.h>
@@ -21,9 +20,11 @@
 #include <linux/major.h>
 #include <linux/console.h>
 #include <linux/kdev_t.h>
-#include <linux/bootmem.h>
 #include <linux/interrupt.h>
 #include <linux/init.h>
+#include <linux/reboot.h>
+#include <linux/slab.h>
+
 #include <asm/uaccess.h>
 #include "sclp.h"
 
@@ -33,7 +34,6 @@
 #define SCLP_VT220_DEVICE_NAME		"ttysclp"
 #define SCLP_VT220_CONSOLE_NAME		"ttyS"
 #define SCLP_VT220_CONSOLE_INDEX	1	/* console=ttyS1 */
-#define SCLP_VT220_BUF_SIZE		80
 
 /* Representation of a single write request */
 struct sclp_vt220_request {
@@ -55,8 +55,7 @@ struct sclp_vt220_sccb {
 /* Structures and data needed to register tty driver */
 static struct tty_driver *sclp_vt220_driver;
 
-/* The tty_struct that the kernel associated with us */
-static struct tty_struct *sclp_vt220_tty;
+static struct tty_port sclp_vt220_port;
 
 /* Lock to protect internal data from concurrent access */
 static spinlock_t sclp_vt220_lock;
@@ -67,8 +66,11 @@ static struct list_head sclp_vt220_empty;
 /* List of pending requests */
 static struct list_head sclp_vt220_outqueue;
 
-/* Number of requests in outqueue */
-static int sclp_vt220_outqueue_count;
+/* Suspend mode flag */
+static int sclp_vt220_suspended;
+
+/* Flag that output queue is currently running */
+static int sclp_vt220_queue_running;
 
 /* Timer used for delaying write requests to merge subsequent messages into
  * a single buffer */
@@ -90,15 +92,21 @@ static int __initdata sclp_vt220_init_count;
 static int sclp_vt220_flush_later;
 
 static void sclp_vt220_receiver_fn(struct evbuf_header *evbuf);
+static void sclp_vt220_pm_event_fn(struct sclp_register *reg,
+				   enum sclp_pm_event sclp_pm_event);
 static int __sclp_vt220_emit(struct sclp_vt220_request *request);
 static void sclp_vt220_emit_current(void);
 
-/* Registration structure for our interest in SCLP event buffers */
+/* Registration structure for SCLP output event buffers */
 static struct sclp_register sclp_vt220_register = {
 	.send_mask		= EVTYP_VT220MSG_MASK,
+	.pm_event_fn		= sclp_vt220_pm_event_fn,
+};
+
+/* Registration structure for SCLP input event buffers */
+static struct sclp_register sclp_vt220_register_input = {
 	.receive_mask		= EVTYP_VT220MSG_MASK,
-	.state_change_fn	= NULL,
-	.receiver_fn		= sclp_vt220_receiver_fn
+	.receiver_fn		= sclp_vt220_receiver_fn,
 };
 
 
@@ -118,21 +126,22 @@ sclp_vt220_process_queue(struct sclp_vt220_request *request)
 		spin_lock_irqsave(&sclp_vt220_lock, flags);
 		/* Move request from outqueue to empty queue */
 		list_del(&request->list);
-		sclp_vt220_outqueue_count--;
 		list_add_tail((struct list_head *) page, &sclp_vt220_empty);
 		/* Check if there is a pending buffer on the out queue. */
 		request = NULL;
 		if (!list_empty(&sclp_vt220_outqueue))
 			request = list_entry(sclp_vt220_outqueue.next,
 					     struct sclp_vt220_request, list);
+		if (!request || sclp_vt220_suspended) {
+			sclp_vt220_queue_running = 0;
+			spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+			break;
+		}
 		spin_unlock_irqrestore(&sclp_vt220_lock, flags);
-	} while (request && __sclp_vt220_emit(request));
+	} while (__sclp_vt220_emit(request));
 	if (request == NULL && sclp_vt220_flush_later)
 		sclp_vt220_emit_current();
-	/* Check if the tty needs a wake up call */
-	if (sclp_vt220_tty != NULL) {
-		tty_wakeup(sclp_vt220_tty);
-	}
+	tty_port_tty_wakeup(&sclp_vt220_port);
 }
 
 #define SCLP_BUFFER_MAX_RETRY		1
@@ -210,26 +219,7 @@ __sclp_vt220_emit(struct sclp_vt220_request *request)
 }
 
 /*
- * Queue and emit given request.
- */
-static void
-sclp_vt220_emit(struct sclp_vt220_request *request)
-{
-	unsigned long flags;
-	int count;
-
-	spin_lock_irqsave(&sclp_vt220_lock, flags);
-	list_add_tail(&request->list, &sclp_vt220_outqueue);
-	count = sclp_vt220_outqueue_count++;
-	spin_unlock_irqrestore(&sclp_vt220_lock, flags);
-	/* Emit only the first buffer immediately - callback takes care of
-	 * the rest */
-	if (count == 0 && __sclp_vt220_emit(request))
-		sclp_vt220_process_queue(request);
-}
-
-/*
- * Queue and emit current request. Return zero on success, non-zero otherwise.
+ * Queue and emit current request.
  */
 static void
 sclp_vt220_emit_current(void)
@@ -239,22 +229,33 @@ sclp_vt220_emit_current(void)
 	struct sclp_vt220_sccb *sccb;
 
 	spin_lock_irqsave(&sclp_vt220_lock, flags);
-	request = NULL;
-	if (sclp_vt220_current_request != NULL) {
+	if (sclp_vt220_current_request) {
 		sccb = (struct sclp_vt220_sccb *) 
 				sclp_vt220_current_request->sclp_req.sccb;
 		/* Only emit buffers with content */
 		if (sccb->header.length != sizeof(struct sclp_vt220_sccb)) {
-			request = sclp_vt220_current_request;
+			list_add_tail(&sclp_vt220_current_request->list,
+				      &sclp_vt220_outqueue);
 			sclp_vt220_current_request = NULL;
 			if (timer_pending(&sclp_vt220_timer))
 				del_timer(&sclp_vt220_timer);
 		}
 		sclp_vt220_flush_later = 0;
 	}
+	if (sclp_vt220_queue_running || sclp_vt220_suspended)
+		goto out_unlock;
+	if (list_empty(&sclp_vt220_outqueue))
+		goto out_unlock;
+	request = list_first_entry(&sclp_vt220_outqueue,
+				   struct sclp_vt220_request, list);
+	sclp_vt220_queue_running = 1;
+	spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+
+	if (__sclp_vt220_emit(request))
+		sclp_vt220_process_queue(request);
+	return;
+out_unlock:
 	spin_unlock_irqrestore(&sclp_vt220_lock, flags);
-	if (request != NULL)
-		sclp_vt220_emit(request);
 }
 
 #define SCLP_NORMAL_WRITE	0x00
@@ -364,6 +365,31 @@ sclp_vt220_timeout(unsigned long data)
 
 #define BUFFER_MAX_DELAY	HZ/20
 
+/*
+ * Drop oldest console buffer if sclp_con_drop is set
+ */
+static int
+sclp_vt220_drop_buffer(void)
+{
+	struct list_head *list;
+	struct sclp_vt220_request *request;
+	void *page;
+
+	if (!sclp_console_drop)
+		return 0;
+	list = sclp_vt220_outqueue.next;
+	if (sclp_vt220_queue_running)
+		/* The first element is in I/O */
+		list = list->next;
+	if (list == &sclp_vt220_outqueue)
+		return 0;
+	list_del(list);
+	request = list_entry(list, struct sclp_vt220_request, list);
+	page = request->sclp_req.sccb;
+	list_add_tail((struct list_head *) page, &sclp_vt220_empty);
+	return 1;
+}
+
 /* 
  * Internal implementation of the write function. Write COUNT bytes of data
  * from memory at BUF
@@ -392,12 +418,16 @@ __sclp_vt220_write(const unsigned char *buf, int count, int do_schedule,
 	do {
 		/* Create an sclp output buffer if none exists yet */
 		if (sclp_vt220_current_request == NULL) {
+			if (list_empty(&sclp_vt220_empty))
+				sclp_console_full++;
 			while (list_empty(&sclp_vt220_empty)) {
-				spin_unlock_irqrestore(&sclp_vt220_lock, flags);
-				if (may_fail)
+				if (may_fail || sclp_vt220_suspended)
 					goto out;
-				else
-					sclp_sync_wait();
+				if (sclp_vt220_drop_buffer())
+					break;
+				spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+
+				sclp_sync_wait();
 				spin_lock_irqsave(&sclp_vt220_lock, flags);
 			}
 			page = (void *) sclp_vt220_empty.next;
@@ -430,8 +460,8 @@ __sclp_vt220_write(const unsigned char *buf, int count, int do_schedule,
 		sclp_vt220_timer.expires = jiffies + BUFFER_MAX_DELAY;
 		add_timer(&sclp_vt220_timer);
 	}
-	spin_unlock_irqrestore(&sclp_vt220_lock, flags);
 out:
+	spin_unlock_irqrestore(&sclp_vt220_lock, flags);
 	return overall_written;
 }
 
@@ -460,10 +490,6 @@ sclp_vt220_receiver_fn(struct evbuf_header *evbuf)
 	char *buffer;
 	unsigned int count;
 
-	/* Ignore input if device is not open */
-	if (sclp_vt220_tty == NULL)
-		return;
-
 	buffer = (char *) ((addr_t) evbuf + sizeof(struct evbuf_header));
 	count = evbuf->length - sizeof(struct evbuf_header);
 
@@ -475,8 +501,8 @@ sclp_vt220_receiver_fn(struct evbuf_header *evbuf)
 		/* Send input to line discipline */
 		buffer++;
 		count--;
-		tty_insert_flip_string(sclp_vt220_tty, buffer, count);
-		tty_flip_buffer_push(sclp_vt220_tty);
+		tty_insert_flip_string(&sclp_vt220_port, buffer, count);
+		tty_flip_buffer_push(&sclp_vt220_port);
 		break;
 	}
 }
@@ -488,11 +514,12 @@ static int
 sclp_vt220_open(struct tty_struct *tty, struct file *filp)
 {
 	if (tty->count == 1) {
-		sclp_vt220_tty = tty;
-		tty->driver_data = kmalloc(SCLP_VT220_BUF_SIZE, GFP_KERNEL);
-		if (tty->driver_data == NULL)
-			return -ENOMEM;
-		tty->low_latency = 0;
+		tty_port_tty_set(&sclp_vt220_port, tty);
+		sclp_vt220_port.low_latency = 0;
+		if (!tty->winsize.ws_row && !tty->winsize.ws_col) {
+			tty->winsize.ws_row = 24;
+			tty->winsize.ws_col = 80;
+		}
 	}
 	return 0;
 }
@@ -503,11 +530,8 @@ sclp_vt220_open(struct tty_struct *tty, struct file *filp)
 static void
 sclp_vt220_close(struct tty_struct *tty, struct file *filp)
 {
-	if (tty->count == 1) {
-		sclp_vt220_tty = NULL;
-		kfree(tty->driver_data);
-		tty->driver_data = NULL;
-	}
+	if (tty->count == 1)
+		tty_port_tty_set(&sclp_vt220_port, NULL);
 }
 
 /*
@@ -529,7 +553,7 @@ sclp_vt220_put_char(struct tty_struct *tty, unsigned char ch)
 static void
 sclp_vt220_flush_chars(struct tty_struct *tty)
 {
-	if (sclp_vt220_outqueue_count == 0)
+	if (!sclp_vt220_queue_running)
 		sclp_vt220_emit_current();
 	else
 		sclp_vt220_flush_later = 1;
@@ -581,23 +605,6 @@ sclp_vt220_chars_in_buffer(struct tty_struct *tty)
 	return count;
 }
 
-static void
-__sclp_vt220_flush_buffer(void)
-{
-	unsigned long flags;
-
-	sclp_vt220_emit_current();
-	spin_lock_irqsave(&sclp_vt220_lock, flags);
-	if (timer_pending(&sclp_vt220_timer))
-		del_timer(&sclp_vt220_timer);
-	while (sclp_vt220_outqueue_count > 0) {
-		spin_unlock_irqrestore(&sclp_vt220_lock, flags);
-		sclp_sync_wait();
-		spin_lock_irqsave(&sclp_vt220_lock, flags);
-	}
-	spin_unlock_irqrestore(&sclp_vt220_lock, flags);
-}
-
 /*
  * Pass on all buffers to the hardware. Return only when there are no more
  * buffers pending.
@@ -615,10 +622,7 @@ static void __init __sclp_vt220_free_pages(void)
 
 	list_for_each_safe(page, p, &sclp_vt220_empty) {
 		list_del(page);
-		if (slab_is_available())
-			free_page((unsigned long) page);
-		else
-			free_bootmem((unsigned long) page, PAGE_SIZE);
+		free_page((unsigned long) page);
 	}
 }
 
@@ -631,6 +635,7 @@ static void __init __sclp_vt220_cleanup(void)
 		return;
 	sclp_unregister(&sclp_vt220_register);
 	__sclp_vt220_free_pages();
+	tty_port_destroy(&sclp_vt220_port);
 }
 
 /* Allocate buffer pages and register with sclp core. Controlled by init
@@ -648,29 +653,25 @@ static int __init __sclp_vt220_init(int num_pages)
 	INIT_LIST_HEAD(&sclp_vt220_empty);
 	INIT_LIST_HEAD(&sclp_vt220_outqueue);
 	init_timer(&sclp_vt220_timer);
+	tty_port_init(&sclp_vt220_port);
 	sclp_vt220_current_request = NULL;
 	sclp_vt220_buffered_chars = 0;
-	sclp_vt220_outqueue_count = 0;
-	sclp_vt220_tty = NULL;
 	sclp_vt220_flush_later = 0;
 
 	/* Allocate pages for output buffering */
+	rc = -ENOMEM;
 	for (i = 0; i < num_pages; i++) {
-		if (slab_is_available())
-			page = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
-		else
-			page = alloc_bootmem_low_pages(PAGE_SIZE);
-		if (!page) {
-			rc = -ENOMEM;
+		page = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
+		if (!page)
 			goto out;
-		}
-		list_add_tail((struct list_head *) page, &sclp_vt220_empty);
+		list_add_tail(page, &sclp_vt220_empty);
 	}
 	rc = sclp_register(&sclp_vt220_register);
 out:
 	if (rc) {
 		__sclp_vt220_free_pages();
 		sclp_vt220_init_count--;
+		tty_port_destroy(&sclp_vt220_port);
 	}
 	return rc;
 }
@@ -703,7 +704,6 @@ static int __init sclp_vt220_tty_init(void)
 	if (rc)
 		goto out_driver;
 
-	driver->owner = THIS_MODULE;
 	driver->driver_name = SCLP_VT220_DRIVER_NAME;
 	driver->name = SCLP_VT220_DEVICE_NAME;
 	driver->major = SCLP_VT220_MAJOR;
@@ -713,13 +713,19 @@ static int __init sclp_vt220_tty_init(void)
 	driver->init_termios = tty_std_termios;
 	driver->flags = TTY_DRIVER_REAL_RAW;
 	tty_set_operations(driver, &sclp_vt220_ops);
+	tty_port_link_device(&sclp_vt220_port, driver, 0);
 
 	rc = tty_register_driver(driver);
 	if (rc)
 		goto out_init;
+	rc = sclp_register(&sclp_vt220_register_input);
+	if (rc)
+		goto out_reg;
 	sclp_vt220_driver = driver;
 	return 0;
 
+out_reg:
+	tty_unregister_driver(driver);
 out_init:
 	__sclp_vt220_cleanup();
 out_driver:
@@ -728,6 +734,62 @@ out_driver:
 }
 __initcall(sclp_vt220_tty_init);
 
+static void __sclp_vt220_flush_buffer(void)
+{
+	unsigned long flags;
+
+	sclp_vt220_emit_current();
+	spin_lock_irqsave(&sclp_vt220_lock, flags);
+	if (timer_pending(&sclp_vt220_timer))
+		del_timer(&sclp_vt220_timer);
+	while (sclp_vt220_queue_running) {
+		spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+		sclp_sync_wait();
+		spin_lock_irqsave(&sclp_vt220_lock, flags);
+	}
+	spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+}
+
+/*
+ * Resume console: If there are cached messages, emit them.
+ */
+static void sclp_vt220_resume(void)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&sclp_vt220_lock, flags);
+	sclp_vt220_suspended = 0;
+	spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+	sclp_vt220_emit_current();
+}
+
+/*
+ * Suspend console: Set suspend flag and flush console
+ */
+static void sclp_vt220_suspend(void)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&sclp_vt220_lock, flags);
+	sclp_vt220_suspended = 1;
+	spin_unlock_irqrestore(&sclp_vt220_lock, flags);
+	__sclp_vt220_flush_buffer();
+}
+
+static void sclp_vt220_pm_event_fn(struct sclp_register *reg,
+				   enum sclp_pm_event sclp_pm_event)
+{
+	switch (sclp_pm_event) {
+	case SCLP_PM_EVENT_FREEZE:
+		sclp_vt220_suspend();
+		break;
+	case SCLP_PM_EVENT_RESTORE:
+	case SCLP_PM_EVENT_THAW:
+		sclp_vt220_resume();
+		break;
+	}
+}
+
 #ifdef CONFIG_SCLP_VT220_CONSOLE
 
 static void
@@ -743,24 +805,30 @@ sclp_vt220_con_device(struct console *c, int *index)
 	return sclp_vt220_driver;
 }
 
-/*
- * This routine is called from panic when the kernel is going to give up.
- * We have to make sure that all buffers will be flushed to the SCLP.
- * Note that this function may be called from within an interrupt context.
- */
-static void
-sclp_vt220_con_unblank(void)
+static int
+sclp_vt220_notify(struct notifier_block *self,
+			  unsigned long event, void *data)
 {
 	__sclp_vt220_flush_buffer();
+	return NOTIFY_OK;
 }
 
+static struct notifier_block on_panic_nb = {
+	.notifier_call = sclp_vt220_notify,
+	.priority = 1,
+};
+
+static struct notifier_block on_reboot_nb = {
+	.notifier_call = sclp_vt220_notify,
+	.priority = 1,
+};
+
 /* Structure needed to register with printk */
 static struct console sclp_vt220_console =
 {
 	.name = SCLP_VT220_CONSOLE_NAME,
 	.write = sclp_vt220_con_write,
 	.device = sclp_vt220_con_device,
-	.unblank = sclp_vt220_con_unblank,
 	.flags = CON_PRINTBUFFER,
 	.index = SCLP_VT220_CONSOLE_INDEX
 };
@@ -770,12 +838,12 @@ sclp_vt220_con_init(void)
 {
 	int rc;
 
-	if (!CONSOLE_IS_SCLP)
-		return 0;
-	rc = __sclp_vt220_init(MAX_CONSOLE_PAGES);
+	rc = __sclp_vt220_init(sclp_console_pages);
 	if (rc)
 		return rc;
 	/* Attach linux console */
+	atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb);
+	register_reboot_notifier(&on_reboot_nb);
 	register_console(&sclp_vt220_console);
 	return 0;
 }