1 files changed, 37 insertions, 5 deletions

diff --git a/include/linux/tty.h b/include/linux/tty.h
index f0f43d08d8b8..4409967db0c4 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -68,6 +68,17 @@ struct tty_buffer {
         unsigned long data[0];
 };
 
+/*
+ * We default to dicing tty buffer allocations to this many characters
+ * in order to avoid multiple page allocations. We know the size of
+ * tty_buffer itself but it must also be taken into account that the
+ * the buffer is 256 byte aligned. See tty_buffer_find for the allocation
+ * logic this must match
+ */
+
+#define TTY_BUFFER_PAGE (((PAGE_SIZE - sizeof(struct tty_buffer)) / 2) & ~0xFF)
+
+
 struct tty_bufhead {
         struct delayed_work work;
         spinlock_t lock;
@@ -190,9 +201,17 @@ struct tty_port_operations {
         /* Control the DTR line */
         void (*dtr_rts)(struct tty_port *port, int raise);
         /* Called when the last close completes or a hangup finishes
-           IFF the port was initialized. Do not use to free resources */
+           IFF the port was initialized. Do not use to free resources. Called
+           under the port mutex to serialize against activate/shutdowns */
         void (*shutdown)(struct tty_port *port);
         void (*drop)(struct tty_port *port);
+        /* Called under the port mutex from tty_port_open, serialized using
+           the port mutex */
+        /* FIXME: long term getting the tty argument *out* of this would be
+           good for consoles */
+        int (*activate)(struct tty_port *port, struct tty_struct *tty);
+        /* Called on the final put of a port */
+        void (*destruct)(struct tty_port *port);
 };
         
 struct tty_port {
@@ -205,13 +224,16 @@ struct tty_port {
         wait_queue_head_t       close_wait;     /* Close waiters */
         wait_queue_head_t       delta_msr_wait; /* Modem status change */
         unsigned long           flags;          /* TTY flags ASY_*/
+        unsigned char           console:1;      /* port is a console */
         struct mutex            mutex;          /* Locking */
+        struct mutex            buf_mutex;      /* Buffer alloc lock */
         unsigned char           *xmit_buf;      /* Optional buffer */
         unsigned int            close_delay;    /* Close port delay */
         unsigned int            closing_wait;   /* Delay for output */
         int                     drain_delay;    /* Set to zero if no pure time
                                                    based drain is needed else
                                                    set to size of fifo */
+        struct kref             kref;           /* Ref counter */
 };
 
 /*
@@ -340,8 +362,6 @@ extern void tty_write_flush(struct tty_struct *);
 
 extern struct ktermios tty_std_termios;
 
-extern int kmsg_redirect;
-
 extern void console_init(void);
 extern int vcs_init(void);
 
@@ -439,7 +459,7 @@ extern void initialize_tty_struct(struct tty_struct *tty,
                 struct tty_driver *driver, int idx);
 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx,
                                                                 int first_ok);
-extern void tty_release_dev(struct file *filp);
+extern int tty_release(struct inode *inode, struct file *filp);
 extern int tty_init_termios(struct tty_struct *tty);
 
 extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty);
@@ -454,6 +474,15 @@ extern int tty_write_lock(struct tty_struct *tty, int ndelay);
 extern void tty_port_init(struct tty_port *port);
 extern int tty_port_alloc_xmit_buf(struct tty_port *port);
 extern void tty_port_free_xmit_buf(struct tty_port *port);
+extern void tty_port_put(struct tty_port *port);
+
+static inline struct tty_port *tty_port_get(struct tty_port *port)
+{
+        if (port)
+                kref_get(&port->kref);
+        return port;
+}
+
 extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
 extern int tty_port_carrier_raised(struct tty_port *port);
@@ -467,7 +496,9 @@ extern int tty_port_close_start(struct tty_port *port,
 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
 extern void tty_port_close(struct tty_port *port,
                                 struct tty_struct *tty, struct file *filp);
-extern inline int tty_port_users(struct tty_port *port)
+extern int tty_port_open(struct tty_port *port,
+                                struct tty_struct *tty, struct file *filp);
+static inline int tty_port_users(struct tty_port *port)
 {
         return port->count + port->blocked_open;
 }
@@ -485,6 +516,7 @@ extern void tty_ldisc_enable(struct tty_struct *tty);
 
 /* n_tty.c */
 extern struct tty_ldisc_ops tty_ldisc_N_TTY;
+extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
 
 /* tty_audit.c */
 #ifdef CONFIG_AUDIT