4 files changed, 31 insertions, 25 deletions

diff --git a/include/linux/kbd_kern.h b/include/linux/kbd_kern.h
index 7428198111eb..45f625d7d0b2 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 57449704a47b..3787102e4b12 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 abe9bfcf226c..be1400e82482 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 6066afde5ce4..83c6e6c10ebb 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;