hvc_console: Provide (un)locked version for hvc_resize()

Rename the locking free hvc_resize() function to __hvc_resize() and
provide an inline function that locks the hvc_struct and calls
__hvc_resize().

The rationale for this patch is that virtio_console calls the hvc_resize()
function without locking the hvc_struct. So it needs to call the lock
itself.

According to naming rules, the unlocked version is renamed and
prefixed with "__".
References to unlocked function calls in hvc back-ends has been updated.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 11 insertions, 1 deletions

diff --git a/drivers/char/hvc_console.h b/drivers/char/hvc_console.h
index 3c85d78..10950ca 100644
--- a/drivers/char/hvc_console.h
+++ b/drivers/char/hvc_console.h
@@ -28,6 +28,7 @@
 #define HVC_CONSOLE_H
 #include <linux/kref.h>
 #include <linux/tty.h>
+#include <linux/spinlock.h>
 
 /*
  * This is the max number of console adapters that can/will be found as
@@ -88,7 +89,16 @@ 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);
+extern void __hvc_resize(struct hvc_struct *hp, struct winsize ws);
+
+static inline void hvc_resize(struct hvc_struct *hp, struct winsize ws)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&hp->lock, flags);
+	__hvc_resize(hp, ws);
+	spin_unlock_irqrestore(&hp->lock, flags);
+}
 
 /* default notifier for irq based notification */
 extern int notifier_add_irq(struct hvc_struct *hp, int data);