4 files changed, 31 insertions, 25 deletions

diff --git a/include/linux/kbd_kern.h b/include/linux/kbd_kern.h
index 7428198111e..45f625d7d0b 100644
--- a/include/linux/kbd_kern.h
+++ b/include/linux/kbd_kern.h
@@ -151,7 +151,7 @@ extern unsigned int keymap_count;
 
 static inline void con_schedule_flip(struct tty_struct *t)
 {
-	schedule_work(&t->flip.work);
+	schedule_work(&t->buf.work);
 }
 
 #endif
diff --git a/include/linux/tty.h b/include/linux/tty.h
index 57449704a47..3787102e4b1 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -51,16 +51,22 @@
  */
 #define TTY_FLIPBUF_SIZE 512
 
-struct tty_flip_buffer {
+struct tty_buffer {
+	struct tty_buffer *next;
+	char *char_buf_ptr;
+	unsigned char *flag_buf_ptr;
+	int used;
+	int size;
+	/* Data points here */
+	unsigned long data[0];
+};
+
+struct tty_bufhead {
 	struct work_struct		work;
 	struct semaphore pty_sem;
-	char		*char_buf_ptr;
-	unsigned char	*flag_buf_ptr;
-	int		count;
-	int		buf_num;
-	unsigned char	char_buf[2*TTY_FLIPBUF_SIZE];
-	char		flag_buf[2*TTY_FLIPBUF_SIZE];
-	unsigned char	slop[4]; /* N.B. bug overwrites buffer by 1 */
+	struct tty_buffer *head;	/* Queue head */
+	struct tty_buffer *tail;	/* Active buffer */
+	struct tty_buffer *free;	/* Free queue head */
 };
 /*
  * The pty uses char_buf and flag_buf as a contiguous buffer
@@ -186,10 +192,11 @@ struct tty_struct {
 	unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1;
 	unsigned char low_latency:1, warned:1;
 	unsigned char ctrl_status;
+	unsigned int receive_room;	/* Bytes free for queue */
 
 	struct tty_struct *link;
 	struct fasync_struct *fasync;
-	struct tty_flip_buffer flip;
+	struct tty_bufhead buf;
 	int max_flip_cnt;
 	int alt_speed;		/* For magic substitution of 38400 bps */
 	wait_queue_head_t write_wait;
diff --git a/include/linux/tty_flip.h b/include/linux/tty_flip.h
index abe9bfcf226..be1400e8248 100644
--- a/include/linux/tty_flip.h
+++ b/include/linux/tty_flip.h
@@ -1,25 +1,33 @@
 #ifndef _LINUX_TTY_FLIP_H
 #define _LINUX_TTY_FLIP_H
 
+extern int tty_buffer_request_room(struct tty_struct *tty, size_t size);
+extern int tty_insert_flip_string(struct tty_struct *tty, unsigned char *chars, size_t size);
+extern int tty_insert_flip_string_flags(struct tty_struct *tty, unsigned char *chars, char *flags, size_t size);
+extern int tty_prepare_flip_string(struct tty_struct *tty, unsigned char **chars, size_t size);
+extern int tty_prepare_flip_string_flags(struct tty_struct *tty, unsigned char **chars, char **flags, size_t size);
+
 #ifdef INCLUDE_INLINE_FUNCS
 #define _INLINE_ extern
 #else
 #define _INLINE_ static __inline__
 #endif
 
-_INLINE_ void tty_insert_flip_char(struct tty_struct *tty,
+_INLINE_ int tty_insert_flip_char(struct tty_struct *tty,
 				   unsigned char ch, char flag)
 {
-	if (tty->flip.count < TTY_FLIPBUF_SIZE) {
-		tty->flip.count++;
-		*tty->flip.flag_buf_ptr++ = flag;
-		*tty->flip.char_buf_ptr++ = ch;
+	struct tty_buffer *tb = tty->buf.tail;
+	if (tb && tb->used < tb->size) {
+		tb->flag_buf_ptr[tb->used] = flag;
+		tb->char_buf_ptr[tb->used++] = ch;
+		return 1;
 	}
+	return tty_insert_flip_string_flags(tty, &ch, &flag, 1);
 }
 
 _INLINE_ void tty_schedule_flip(struct tty_struct *tty)
 {
-	schedule_delayed_work(&tty->flip.work, 1);
+	schedule_delayed_work(&tty->buf.work, 1);
 }
 
 #undef _INLINE_
diff --git a/include/linux/tty_ldisc.h b/include/linux/tty_ldisc.h
index 6066afde5ce..83c6e6c10eb 100644
--- a/include/linux/tty_ldisc.h
+++ b/include/linux/tty_ldisc.h
@@ -81,14 +81,6 @@
  * 	pointer of flag bytes which indicate whether a character was
  * 	received with a parity error, etc.
  * 
- * int	(*receive_room)(struct tty_struct *);
- *
- * 	This function is called by the low-level tty driver to
- * 	determine how many characters the line discpline can accept.
- * 	The low-level driver must not send more characters than was
- * 	indicated by receive_room, or the line discpline may drop
- * 	those characters.
- * 
  * void	(*write_wakeup)(struct tty_struct *);
  *
  * 	This function is called by the low-level tty driver to signal
@@ -136,7 +128,6 @@ struct tty_ldisc {
 	 */
 	void	(*receive_buf)(struct tty_struct *, const unsigned char *cp,
 			       char *fp, int count);
-	int	(*receive_room)(struct tty_struct *);
 	void	(*write_wakeup)(struct tty_struct *);
 
 	struct  module *owner;