TTY: hvcs, use kref from tty_port

A simple switch. Except we convert destroy_hvcs_struct to be
tty_port_operations->destruct...

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 16 insertions, 18 deletions

diff --git a/drivers/tty/hvc/hvcs.c b/drivers/tty/hvc/hvcs.c
index a049ced97430..817f94bf95a1 100644
--- a/drivers/tty/hvc/hvcs.c
+++ b/drivers/tty/hvc/hvcs.c
@@ -290,12 +290,11 @@ struct hvcs_struct {
         int chars_in_buffer;
 
         /*
-         * Any variable below the kref is valid before a tty is connected and
+         * Any variable below is valid before a tty is connected and
          * stays valid after the tty is disconnected.  These shouldn't be
          * whacked until the kobject refcount reaches zero though some entries
          * may be changed via sysfs initiatives.
          */
-        struct kref kref; /* ref count & hvcs_struct lifetime */
         int connected; /* is the vty-server currently connected to a vty? */
         uint32_t p_unit_address; /* partner unit address */
         uint32_t p_partition_ID; /* partner partition ID */
@@ -304,9 +303,6 @@ struct hvcs_struct {
         struct vio_dev *vdev;
 };
 
-/* Required to back map a kref to its containing object */
-#define from_kref(k) container_of(k, struct hvcs_struct, kref)
-
 static LIST_HEAD(hvcs_structs);
 static DEFINE_SPINLOCK(hvcs_structs_lock);
 static DEFINE_MUTEX(hvcs_init_mutex);
@@ -701,10 +697,9 @@ static void hvcs_return_index(int index)
                 hvcs_index_list[index] = -1;
 }
 
-/* callback when the kref ref count reaches zero */
-static void destroy_hvcs_struct(struct kref *kref)
+static void hvcs_destruct_port(struct tty_port *p)
 {
-        struct hvcs_struct *hvcsd = from_kref(kref);
+        struct hvcs_struct *hvcsd = container_of(p, struct hvcs_struct, port);
         struct vio_dev *vdev;
         unsigned long flags;
 
@@ -741,6 +736,10 @@ static void destroy_hvcs_struct(struct kref *kref)
         kfree(hvcsd);
 }
 
+static const struct tty_port_operations hvcs_port_ops = {
+        .destruct = hvcs_destruct_port,
+};
+
 static int hvcs_get_index(void)
 {
         int i;
@@ -790,9 +789,8 @@ static int __devinit hvcs_probe(
                 return -ENODEV;
 
         tty_port_init(&hvcsd->port);
+        hvcsd->port.ops = &hvcs_port_ops;
         spin_lock_init(&hvcsd->lock);
-        /* Automatically incs the refcount the first time */
-        kref_init(&hvcsd->kref);
 
         hvcsd->vdev = dev;
         dev_set_drvdata(&dev->dev, hvcsd);
@@ -860,7 +858,7 @@ static int __devexit hvcs_remove(struct vio_dev *dev)
          * Let the last holder of this object cause it to be removed, which
          * would probably be tty_hangup below.
          */
-        kref_put(&hvcsd->kref, destroy_hvcs_struct);
+        tty_port_put(&hvcsd->port);
 
         /*
          * The hangup is a scheduled function which will auto chain call
@@ -1094,7 +1092,7 @@ static struct hvcs_struct *hvcs_get_by_index(int index)
         list_for_each_entry(hvcsd, &hvcs_structs, next) {
                 spin_lock_irqsave(&hvcsd->lock, flags);
                 if (hvcsd->index == index) {
-                        kref_get(&hvcsd->kref);
+                        tty_port_get(&hvcsd->port);
                         spin_unlock_irqrestore(&hvcsd->lock, flags);
                         spin_unlock(&hvcs_structs_lock);
                         return hvcsd;
@@ -1160,7 +1158,7 @@ static int hvcs_open(struct tty_struct *tty, struct file *filp)
          * and will grab the spinlock and free the connection if it fails.
          */
         if (((rc = hvcs_enable_device(hvcsd, unit_address, irq, vdev)))) {
-                kref_put(&hvcsd->kref, destroy_hvcs_struct);
+                tty_port_put(&hvcsd->port);
                 printk(KERN_WARNING "HVCS: enable device failed.\n");
                 return rc;
         }
@@ -1171,7 +1169,7 @@ fast_open:
         hvcsd = tty->driver_data;
 
         spin_lock_irqsave(&hvcsd->lock, flags);
-        kref_get(&hvcsd->kref);
+        tty_port_get(&hvcsd->port);
         hvcsd->port.count++;
         hvcsd->todo_mask |= HVCS_SCHED_READ;
         spin_unlock_irqrestore(&hvcsd->lock, flags);
@@ -1186,7 +1184,7 @@ open_success:
 
 error_release:
         spin_unlock_irqrestore(&hvcsd->lock, flags);
-        kref_put(&hvcsd->kref, destroy_hvcs_struct);
+        tty_port_put(&hvcsd->port);
 
         printk(KERN_WARNING "HVCS: partner connect failed.\n");
         return retval;
@@ -1240,7 +1238,7 @@ static void hvcs_close(struct tty_struct *tty, struct file *filp)
                 tty->driver_data = NULL;
 
                 free_irq(irq, hvcsd);
-                kref_put(&hvcsd->kref, destroy_hvcs_struct);
+                tty_port_put(&hvcsd->port);
                 return;
         } else if (hvcsd->port.count < 0) {
                 printk(KERN_ERR "HVCS: vty-server@%X open_count: %d"
@@ -1249,7 +1247,7 @@ static void hvcs_close(struct tty_struct *tty, struct file *filp)
         }
 
         spin_unlock_irqrestore(&hvcsd->lock, flags);
-        kref_put(&hvcsd->kref, destroy_hvcs_struct);
+        tty_port_put(&hvcsd->port);
 }
 
 static void hvcs_hangup(struct tty_struct * tty)
@@ -1301,7 +1299,7 @@ static void hvcs_hangup(struct tty_struct * tty)
                  * NOTE:  If this hangup was signaled from user space then the
                  * final put will never happen.
                  */
-                kref_put(&hvcsd->kref, destroy_hvcs_struct);
+                tty_port_put(&hvcsd->port);
         }
 }