8 files changed, 93 insertions, 16 deletions

diff --git a/drivers/char/hvc_console.c b/drivers/char/hvc_console.c
index bf70450a49cc..5b819b12675a 100644
--- a/drivers/char/hvc_console.c
+++ b/drivers/char/hvc_console.c
@@ -161,7 +161,7 @@ static void hvc_console_print(struct console *co, const char *b,
                         }
                 } else {
                         r = cons_ops[index]->put_chars(vtermnos[index], c, i);
-                        if (r < 0) {
+                        if (r <= 0) {
                                 /* throw away chars on error */
                                 i = 0;
                         } else if (r > 0) {
@@ -374,6 +374,9 @@ static void hvc_close(struct tty_struct *tty, struct file * filp)
                 if (hp->ops->notifier_del)
                         hp->ops->notifier_del(hp, hp->data);
 
+                /* cancel pending tty resize work */
+                cancel_work_sync(&hp->tty_resize);
+
                 /*
                  * Chain calls chars_in_buffer() and returns immediately if
                  * there is no buffered data otherwise sleeps on a wait queue
@@ -399,6 +402,9 @@ static void hvc_hangup(struct tty_struct *tty)
         if (!hp)
                 return;
 
+        /* cancel pending tty resize work */
+        cancel_work_sync(&hp->tty_resize);
+
         spin_lock_irqsave(&hp->lock, flags);
 
         /*
@@ -418,8 +424,8 @@ static void hvc_hangup(struct tty_struct *tty)
 
         spin_unlock_irqrestore(&hp->lock, flags);
 
-        if (hp->ops->notifier_del)
-                        hp->ops->notifier_del(hp, hp->data);
+        if (hp->ops->notifier_hangup)
+                        hp->ops->notifier_hangup(hp, hp->data);
 
         while(temp_open_count) {
                 --temp_open_count;
@@ -431,7 +437,7 @@ static void hvc_hangup(struct tty_struct *tty)
  * Push buffered characters whether they were just recently buffered or waiting
  * on a blocked hypervisor.  Call this function with hp->lock held.
  */
-static void hvc_push(struct hvc_struct *hp)
+static int hvc_push(struct hvc_struct *hp)
 {
         int n;
 
@@ -439,7 +445,7 @@ static void hvc_push(struct hvc_struct *hp)
         if (n <= 0) {
                 if (n == 0) {
                         hp->do_wakeup = 1;
-                        return;
+                        return 0;
                 }
                 /* throw away output on error; this happens when
                    there is no session connected to the vterm. */
@@ -450,6 +456,8 @@ static void hvc_push(struct hvc_struct *hp)
                 memmove(hp->outbuf, hp->outbuf + n, hp->n_outbuf);
         else
                 hp->do_wakeup = 1;
+
+        return n;
 }
 
 static int hvc_write(struct tty_struct *tty, const unsigned char *buf, int count)
@@ -492,6 +500,39 @@ static int hvc_write(struct tty_struct *tty, const unsigned char *buf, int count
         return written;
 }
 
+/**
+ * hvc_set_winsz() - Resize the hvc tty terminal window.
+ * @work:       work structure.
+ *
+ * The routine shall not be called within an atomic context because it
+ * might sleep.
+ *
+ * Locking:     hp->lock
+ */
+static void hvc_set_winsz(struct work_struct *work)
+{
+        struct hvc_struct *hp;
+        unsigned long hvc_flags;
+        struct tty_struct *tty;
+        struct winsize ws;
+
+        hp = container_of(work, struct hvc_struct, tty_resize);
+        if (!hp)
+                return;
+
+        spin_lock_irqsave(&hp->lock, hvc_flags);
+        if (!hp->tty) {
+                spin_unlock_irqrestore(&hp->lock, hvc_flags);
+                return;
+        }
+        ws  = hp->ws;
+        tty = tty_kref_get(hp->tty);
+        spin_unlock_irqrestore(&hp->lock, hvc_flags);
+
+        tty_do_resize(tty, tty, &ws);
+        tty_kref_put(tty);
+}
+
 /*
  * This is actually a contract between the driver and the tty layer outlining
  * how much write room the driver can guarantee will be sent OR BUFFERED.  This
@@ -538,16 +579,20 @@ int hvc_poll(struct hvc_struct *hp)
         char buf[N_INBUF] __ALIGNED__;
         unsigned long flags;
         int read_total = 0;
+        int written_total = 0;
 
         spin_lock_irqsave(&hp->lock, flags);
 
         /* Push pending writes */
         if (hp->n_outbuf > 0)
-                hvc_push(hp);
+                written_total = hvc_push(hp);
 
         /* Reschedule us if still some write pending */
-        if (hp->n_outbuf > 0)
+        if (hp->n_outbuf > 0) {
                 poll_mask |= HVC_POLL_WRITE;
+                /* If hvc_push() was not able to write, sleep a few msecs */
+                timeout = (written_total) ? 0 : MIN_TIMEOUT;
+        }
 
         /* No tty attached, just skip */
         tty = hp->tty;
@@ -632,6 +677,24 @@ int hvc_poll(struct hvc_struct *hp)
 }
 EXPORT_SYMBOL_GPL(hvc_poll);
 
+/**
+ * hvc_resize() - Update terminal window size information.
+ * @hp:         HVC console pointer
+ * @ws:         Terminal window size structure
+ *
+ * Stores the specified window size information in the hvc structure of @hp.
+ * The function schedule the tty resize update.
+ *
+ * Locking:     Locking free; the function MUST be called holding hp->lock
+ */
+void hvc_resize(struct hvc_struct *hp, struct winsize ws)
+{
+        if ((hp->ws.ws_row != ws.ws_row) || (hp->ws.ws_col != ws.ws_col)) {
+                hp->ws = ws;
+                schedule_work(&hp->tty_resize);
+        }
+}
+
 /*
  * This kthread is either polling or interrupt driven.  This is determined by
  * calling hvc_poll() who determines whether a console adapter support
@@ -659,10 +722,6 @@ static int khvcd(void *unused)
                         poll_mask |= HVC_POLL_READ;
                 if (hvc_kicked)
                         continue;
-                if (poll_mask & HVC_POLL_WRITE) {
-                        yield();
-                        continue;
-                }
                 set_current_state(TASK_INTERRUPTIBLE);
                 if (!hvc_kicked) {
                         if (poll_mask == 0)
@@ -718,6 +777,7 @@ struct hvc_struct __devinit *hvc_alloc(uint32_t vtermno, int data,
 
         kref_init(&hp->kref);
 
+        INIT_WORK(&hp->tty_resize, hvc_set_winsz);
         spin_lock_init(&hp->lock);
         spin_lock(&hvc_structs_lock);
 
@@ -743,7 +803,7 @@ struct hvc_struct __devinit *hvc_alloc(uint32_t vtermno, int data,
 }
 EXPORT_SYMBOL_GPL(hvc_alloc);
 
-int __devexit hvc_remove(struct hvc_struct *hp)
+int hvc_remove(struct hvc_struct *hp)
 {
         unsigned long flags;
         struct tty_struct *tty;
@@ -796,7 +856,7 @@ static int hvc_init(void)
         drv->minor_start = HVC_MINOR;
         drv->type = TTY_DRIVER_TYPE_SYSTEM;
         drv->init_termios = tty_std_termios;
-        drv->flags = TTY_DRIVER_REAL_RAW;
+        drv->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_RESET_TERMIOS;
         tty_set_operations(drv, &hvc_ops);
 
         /* Always start the kthread because there can be hotplug vty adapters
diff --git a/drivers/char/hvc_console.h b/drivers/char/hvc_console.h
index 9790201718ae..8297dbc2e6ec 100644
--- a/drivers/char/hvc_console.h
+++ b/drivers/char/hvc_console.h
@@ -27,6 +27,7 @@
 #ifndef HVC_CONSOLE_H
 #define HVC_CONSOLE_H
 #include <linux/kref.h>
+#include <linux/tty.h>
 
 /*
  * This is the max number of console adapters that can/will be found as
@@ -56,6 +57,8 @@ struct hvc_struct {
         struct hv_ops *ops;
         int irq_requested;
         int data;
+        struct winsize ws;
+        struct work_struct tty_resize;
         struct list_head next;
         struct kref kref; /* ref count & hvc_struct lifetime */
 };
@@ -65,9 +68,10 @@ struct hv_ops {
         int (*get_chars)(uint32_t vtermno, char *buf, int count);
         int (*put_chars)(uint32_t vtermno, const char *buf, int count);
 
-        /* Callbacks for notification. Called in open and close */
+        /* Callbacks for notification. Called in open, close and hangup */
         int (*notifier_add)(struct hvc_struct *hp, int irq);
         void (*notifier_del)(struct hvc_struct *hp, int irq);
+        void (*notifier_hangup)(struct hvc_struct *hp, int irq);
 };
 
 /* Register a vterm and a slot index for use as a console (console_init) */
@@ -77,15 +81,19 @@ extern int hvc_instantiate(uint32_t vtermno, int index, struct hv_ops *ops);
 extern struct hvc_struct * __devinit hvc_alloc(uint32_t vtermno, int data,
                                 struct hv_ops *ops, int outbuf_size);
 /* remove a vterm from hvc tty operation (module_exit or hotplug remove) */
-extern int __devexit hvc_remove(struct hvc_struct *hp);
+extern int hvc_remove(struct hvc_struct *hp);
 
 /* data available */
 int hvc_poll(struct hvc_struct *hp);
 void hvc_kick(void);
 
+/* Resize hvc tty terminal window */
+extern void hvc_resize(struct hvc_struct *hp, struct winsize ws);
+
 /* default notifier for irq based notification */
 extern int notifier_add_irq(struct hvc_struct *hp, int data);
 extern void notifier_del_irq(struct hvc_struct *hp, int data);
+extern void notifier_hangup_irq(struct hvc_struct *hp, int data);
 
 
 #if defined(CONFIG_XMON) && defined(CONFIG_SMP)
diff --git a/drivers/char/hvc_irq.c b/drivers/char/hvc_irq.c
index 73a59cdb8947..d09e5688d449 100644
--- a/drivers/char/hvc_irq.c
+++ b/drivers/char/hvc_irq.c
@@ -42,3 +42,8 @@ void notifier_del_irq(struct hvc_struct *hp, int irq)
         free_irq(irq, hp);
         hp->irq_requested = 0;
 }
+
+void notifier_hangup_irq(struct hvc_struct *hp, int irq)
+{
+        notifier_del_irq(hp, irq);
+}
diff --git a/drivers/char/hvc_iseries.c b/drivers/char/hvc_iseries.c
index b71c610fe5ae..b74a2f8ab908 100644
--- a/drivers/char/hvc_iseries.c
+++ b/drivers/char/hvc_iseries.c
@@ -202,6 +202,7 @@ static struct hv_ops hvc_get_put_ops = {
         .put_chars = put_chars,
         .notifier_add = notifier_add_irq,
         .notifier_del = notifier_del_irq,
+        .notifier_hangup = notifier_hangup_irq,
 };
 
 static int __devinit hvc_vio_probe(struct vio_dev *vdev,
diff --git a/drivers/char/hvc_vio.c b/drivers/char/hvc_vio.c
index 93f3840c1682..019e0b58593d 100644
--- a/drivers/char/hvc_vio.c
+++ b/drivers/char/hvc_vio.c
@@ -82,6 +82,7 @@ static struct hv_ops hvc_get_put_ops = {
         .put_chars = hvc_put_chars,
         .notifier_add = notifier_add_irq,
         .notifier_del = notifier_del_irq,
+        .notifier_hangup = notifier_hangup_irq,
 };
 
 static int __devinit hvc_vio_probe(struct vio_dev *vdev,
diff --git a/drivers/char/hvc_xen.c b/drivers/char/hvc_xen.c
index 538ceea5e7df..eba999f8598d 100644
--- a/drivers/char/hvc_xen.c
+++ b/drivers/char/hvc_xen.c
@@ -102,6 +102,7 @@ static struct hv_ops hvc_ops = {
         .put_chars = write_console,
         .notifier_add = notifier_add_irq,
         .notifier_del = notifier_del_irq,
+        .notifier_hangup = notifier_hangup_irq,
 };
 
 static int __init xen_init(void)
diff --git a/drivers/char/tty_port.c b/drivers/char/tty_port.c
index 553b0e9d8d17..c8f8024cb40e 100644
--- a/drivers/char/tty_port.c
+++ b/drivers/char/tty_port.c
@@ -90,7 +90,7 @@ void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty)
         spin_lock_irqsave(&port->lock, flags);
         if (port->tty)
                 tty_kref_put(port->tty);
-        port->tty = tty;
+        port->tty = tty_kref_get(tty);
         spin_unlock_irqrestore(&port->lock, flags);
 }
 EXPORT_SYMBOL(tty_port_tty_set);
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index d0f4eb6fdb7f..3fb0d2c88ba5 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -198,6 +198,7 @@ static int __devinit virtcons_probe(struct virtio_device *dev)
         virtio_cons.put_chars = put_chars;
         virtio_cons.notifier_add = notifier_add_vio;
         virtio_cons.notifier_del = notifier_del_vio;
+        virtio_cons.notifier_hangup = notifier_del_vio;
 
         /* The first argument of hvc_alloc() is the virtual console number, so
          * we use zero.  The second argument is the parameter for the