usb_serial: API all change

USB serial likes to use port->tty back pointers for the real work it does and
to do so without any actual locking. Unfortunately when you consider hangup
events, hangup/parallel reopen or even worse hangup followed by parallel close
events the tty->port and port->tty pointers are not guaranteed to be the same
as port->tty is the active tty while tty->port is the port the tty may or
may not still be attached to.

So rework the entire API to pass the tty struct. For console cases we need
to pass both for now. This shows up multiple drivers that immediately crash
with USB console some of which have been fixed in the process.

Longer term we need a proper tty as console abstraction

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 57 insertions, 81 deletions

diff --git a/drivers/usb/serial/keyspan.c b/drivers/usb/serial/keyspan.c
index 11e439b90eac..a371c41bb3ab 100644
--- a/drivers/usb/serial/keyspan.c
+++ b/drivers/usb/serial/keyspan.c
@@ -244,20 +244,9 @@ static void __exit keyspan_exit (void)
 module_init(keyspan_init);
 module_exit(keyspan_exit);
 
-static void keyspan_rx_throttle (struct usb_serial_port *port)
-{
-        dbg("%s - port %d", __func__, port->number);
-}
-
-
-static void keyspan_rx_unthrottle (struct usb_serial_port *port)
-{
-        dbg("%s - port %d", __func__, port->number);
-}
-
-
-static void keyspan_break_ctl (struct usb_serial_port *port, int break_state)
+static void keyspan_break_ctl(struct tty_struct *tty, int break_state)
 {
+        struct usb_serial_port *port = tty->driver_data;
         struct keyspan_port_private     *p_priv;
 
         dbg("%s", __func__);
@@ -273,14 +262,13 @@ static void keyspan_break_ctl (struct usb_serial_port *port, int break_state)
 }
 
 
-static void keyspan_set_termios (struct usb_serial_port *port, 
-                                     struct ktermios *old_termios)
+static void keyspan_set_termios (struct tty_struct *tty,
+                struct usb_serial_port *port, struct ktermios *old_termios)
 {
         int                             baud_rate, device_port;
         struct keyspan_port_private     *p_priv;
         const struct keyspan_device_details     *d_details;
         unsigned int                    cflag;
-        struct tty_struct               *tty = port->tty;
 
         dbg("%s", __func__);
 
@@ -312,12 +300,11 @@ static void keyspan_set_termios (struct usb_serial_port *port,
         keyspan_send_setup(port, 0);
 }
 
-static int keyspan_tiocmget(struct usb_serial_port *port, struct file *file)
+static int keyspan_tiocmget(struct tty_struct *tty, struct file *file)
 {
+        struct usb_serial_port *port = tty->driver_data;
+        struct keyspan_port_private *p_priv = usb_get_serial_port_data(port);
         unsigned int                    value;
-        struct keyspan_port_private     *p_priv;
-
-        p_priv = usb_get_serial_port_data(port);
         
         value = ((p_priv->rts_state) ? TIOCM_RTS : 0) |
                 ((p_priv->dtr_state) ? TIOCM_DTR : 0) |
@@ -329,18 +316,16 @@ static int keyspan_tiocmget(struct usb_serial_port *port, struct file *file)
         return value;
 }
 
-static int keyspan_tiocmset(struct usb_serial_port *port, struct file *file,
+static int keyspan_tiocmset(struct tty_struct *tty, struct file *file,
                             unsigned int set, unsigned int clear)
 {
-        struct keyspan_port_private     *p_priv;
-
-        p_priv = usb_get_serial_port_data(port);
+        struct usb_serial_port *port = tty->driver_data;
+        struct keyspan_port_private *p_priv = usb_get_serial_port_data(port);
         
         if (set & TIOCM_RTS)
                 p_priv->rts_state = 1;
         if (set & TIOCM_DTR)
                 p_priv->dtr_state = 1;
-
         if (clear & TIOCM_RTS)
                 p_priv->rts_state = 0;
         if (clear & TIOCM_DTR)
@@ -349,16 +334,10 @@ static int keyspan_tiocmset(struct usb_serial_port *port, struct file *file,
         return 0;
 }
 
-static int keyspan_ioctl(struct usb_serial_port *port, struct file *file,
-                             unsigned int cmd, unsigned long arg)
-{
-        return -ENOIOCTLCMD;
-}
-
-        /* Write function is similar for the four protocols used
-           with only a minor change for usa90 (usa19hs) required */
-static int keyspan_write(struct usb_serial_port *port, 
-                         const unsigned char *buf, int count)
+/* Write function is similar for the four protocols used
+   with only a minor change for usa90 (usa19hs) required */
+static int keyspan_write(struct tty_struct *tty,
+        struct usb_serial_port *port, const unsigned char *buf, int count)
 {
         struct keyspan_port_private     *p_priv;
         const struct keyspan_device_details     *d_details;
@@ -448,7 +427,7 @@ static void	usa26_indat_callback(struct urb *urb)
         }
 
         port =  urb->context;
-        tty = port->tty;
+        tty = port->port.tty;
         if (tty && urb->actual_length) {
                 /* 0x80 bit is error flag */
                 if ((data[0] & 0x80) == 0) {
@@ -479,7 +458,7 @@ static void	usa26_indat_callback(struct urb *urb)
                                 
                 /* Resubmit urb so we continue receiving */
         urb->dev = port->serial->dev;
-        if (port->open_count)
+        if (port->port.count)
                 if ((err = usb_submit_urb(urb, GFP_ATOMIC)) != 0) {
                         dbg("%s - resubmit read urb failed. (%d)", __func__, err);
                 }
@@ -496,7 +475,7 @@ static void	usa2x_outdat_callback(struct urb *urb)
         p_priv = usb_get_serial_port_data(port);
         dbg ("%s - urb %d", __func__, urb == p_priv->out_urbs[1]);
 
-        if (port->open_count)
+        if (port->port.count)
                 usb_serial_port_softint(port);
 }
 
@@ -567,10 +546,10 @@ static void	usa26_instat_callback(struct urb *urb)
         p_priv->dcd_state = ((msg->gpia_dcd) ? 1 : 0);
         p_priv->ri_state = ((msg->ri) ? 1 : 0);
 
-        if (port->tty && !C_CLOCAL(port->tty)
+        if (port->port.tty && !C_CLOCAL(port->port.tty)
             && old_dcd_state != p_priv->dcd_state) {
                 if (old_dcd_state)
-                        tty_hangup(port->tty);
+                        tty_hangup(port->port.tty);
                 /*  else */
                 /*      wake_up_interruptible(&p_priv->open_wait); */
         }
@@ -619,7 +598,7 @@ static void usa28_indat_callback(struct urb *urb)
                 p_priv = usb_get_serial_port_data(port);
                 data = urb->transfer_buffer;
 
-                tty = port->tty;
+                tty = port->port.tty;
                 if (urb->actual_length) {
                         for (i = 0; i < urb->actual_length ; ++i) {
                                 tty_insert_flip_char(tty, data[i], 0);
@@ -629,7 +608,7 @@ static void usa28_indat_callback(struct urb *urb)
 
                 /* Resubmit urb so we continue receiving */
                 urb->dev = port->serial->dev;
-                if (port->open_count)
+                if (port->port.count)
                         if ((err = usb_submit_urb(urb, GFP_ATOMIC)) != 0) {
                                 dbg("%s - resubmit read urb failed. (%d)", __func__, err);
                         }
@@ -704,10 +683,10 @@ static void	usa28_instat_callback(struct urb *urb)
         p_priv->dcd_state = ((msg->dcd) ? 1 : 0);
         p_priv->ri_state = ((msg->ri) ? 1 : 0);
 
-        if (port->tty && !C_CLOCAL(port->tty)
+        if (port->port.tty && !C_CLOCAL(port->port.tty)
             && old_dcd_state != p_priv->dcd_state) {
                 if (old_dcd_state)
-                        tty_hangup(port->tty);
+                        tty_hangup(port->port.tty);
                 /*  else */
                 /*      wake_up_interruptible(&p_priv->open_wait); */
         }
@@ -797,10 +776,10 @@ static void	usa49_instat_callback(struct urb *urb)
         p_priv->dcd_state = ((msg->dcd) ? 1 : 0);
         p_priv->ri_state = ((msg->ri) ? 1 : 0);
 
-        if (port->tty && !C_CLOCAL(port->tty)
+        if (port->port.tty && !C_CLOCAL(port->port.tty)
             && old_dcd_state != p_priv->dcd_state) {
                 if (old_dcd_state)
-                        tty_hangup(port->tty);
+                        tty_hangup(port->port.tty);
                 /*  else */
                 /*      wake_up_interruptible(&p_priv->open_wait); */
         }
@@ -839,7 +818,7 @@ static void	usa49_indat_callback(struct urb *urb)
         }
 
         port =  urb->context;
-        tty = port->tty;
+        tty = port->port.tty;
         if (tty && urb->actual_length) {
                 /* 0x80 bit is error flag */
                 if ((data[0] & 0x80) == 0) {
@@ -866,7 +845,7 @@ static void	usa49_indat_callback(struct urb *urb)
                                 
                 /* Resubmit urb so we continue receiving */
         urb->dev = port->serial->dev;
-        if (port->open_count)
+        if (port->port.count)
                 if ((err = usb_submit_urb(urb, GFP_ATOMIC)) != 0) {
                         dbg("%s - resubmit read urb failed. (%d)", __func__, err);
                 }
@@ -904,7 +883,7 @@ static void usa49wg_indat_callback(struct urb *urb)
                                 return;
                         }
                         port = serial->port[data[i++]];
-                        tty = port->tty;
+                        tty = port->port.tty;
                         len = data[i++];
 
                         /* 0x80 bit is error flag */
@@ -912,7 +891,7 @@ static void usa49wg_indat_callback(struct urb *urb)
                                 /* no error on any byte */
                                 i++;
                                 for (x = 1; x < len ; ++x)
-                                        if (port->open_count)
+                                        if (port->port.count)
                                                 tty_insert_flip_char(tty,
                                                                 data[i++], 0);
                                         else
@@ -930,13 +909,13 @@ static void usa49wg_indat_callback(struct urb *urb)
                                         if (stat & RXERROR_PARITY)
                                                 flag |= TTY_PARITY;
                                         /* XXX should handle break (0x10) */
-                                        if (port->open_count)
+                                        if (port->port.count)
                                                 tty_insert_flip_char(tty,
                                                         data[i+1], flag);
                                         i += 2;
                                 }
                         }
-                        if (port->open_count)
+                        if (port->port.count)
                                 tty_flip_buffer_push(tty);
                 }
         }
@@ -978,7 +957,7 @@ static void usa90_indat_callback(struct urb *urb)
         port =  urb->context;
         p_priv = usb_get_serial_port_data(port);
 
-        tty = port->tty;
+        tty = port->port.tty;
         if (urb->actual_length) {
         
                 /* if current mode is DMA, looks like usa28 format
@@ -1021,7 +1000,7 @@ static void usa90_indat_callback(struct urb *urb)
                                 
         /* Resubmit urb so we continue receiving */
         urb->dev = port->serial->dev;
-        if (port->open_count)
+        if (port->port.count)
                 if ((err = usb_submit_urb(urb, GFP_ATOMIC)) != 0) {
                         dbg("%s - resubmit read urb failed. (%d)", __func__, err);
                 }
@@ -1064,10 +1043,10 @@ static void	usa90_instat_callback(struct urb *urb)
         p_priv->dcd_state = ((msg->dcd) ? 1 : 0);
         p_priv->ri_state = ((msg->ri) ? 1 : 0);
 
-        if (port->tty && !C_CLOCAL(port->tty)
+        if (port->port.tty && !C_CLOCAL(port->port.tty)
             && old_dcd_state != p_priv->dcd_state) {
                 if (old_dcd_state)
-                        tty_hangup(port->tty);
+                        tty_hangup(port->port.tty);
                 /*  else */
                 /*      wake_up_interruptible(&p_priv->open_wait); */
         }
@@ -1139,10 +1118,10 @@ static void	usa67_instat_callback(struct urb *urb)
         p_priv->cts_state = ((msg->hskia_cts) ? 1 : 0);
         p_priv->dcd_state = ((msg->gpia_dcd) ? 1 : 0);
 
-        if (port->tty && !C_CLOCAL(port->tty)
+        if (port->port.tty && !C_CLOCAL(port->port.tty)
             && old_dcd_state != p_priv->dcd_state) {
                 if (old_dcd_state)
-                        tty_hangup(port->tty);
+                        tty_hangup(port->port.tty);
                 /*  else */
                 /*      wake_up_interruptible(&p_priv->open_wait); */
         }
@@ -1177,8 +1156,9 @@ static void usa67_glocont_callback(struct urb *urb)
         }
 }
 
-static int keyspan_write_room (struct usb_serial_port *port)
+static int keyspan_write_room(struct tty_struct *tty)
 {
+        struct usb_serial_port *port = tty->driver_data;
         struct keyspan_port_private     *p_priv;
         const struct keyspan_device_details     *d_details;
         int                             flip;
@@ -1210,13 +1190,8 @@ static int keyspan_write_room (struct usb_serial_port *port)
 }
 
 
-static int keyspan_chars_in_buffer (struct usb_serial_port *port)
-{
-        return 0;
-}
-
-
-static int keyspan_open (struct usb_serial_port *port, struct file *filp)
+static int keyspan_open(struct tty_struct *tty,
+                        struct usb_serial_port *port, struct file *filp)
 {
         struct keyspan_port_private     *p_priv;
         struct keyspan_serial_private   *s_priv;
@@ -1225,7 +1200,7 @@ static int keyspan_open (struct usb_serial_port *port, struct file *filp)
         int                             i, err;
         int                             baud_rate, device_port;
         struct urb                      *urb;
-        unsigned int                    cflag;
+        unsigned int                    cflag = 0;
 
         s_priv = usb_get_serial_data(serial);
         p_priv = usb_get_serial_port_data(port);
@@ -1271,19 +1246,19 @@ static int keyspan_open (struct usb_serial_port *port, struct file *filp)
         /* get the terminal config for the setup message now so we don't
          * need to send 2 of them */
 
-        cflag = port->tty->termios->c_cflag;
         device_port = port->number - port->serial->minor;
-
-        /* Baud rate calculation takes baud rate as an integer
-           so other rates can be generated if desired. */
-        baud_rate = tty_get_baud_rate(port->tty);
-        /* If no match or invalid, leave as default */
-        if (baud_rate >= 0
-            && d_details->calculate_baud_rate(baud_rate, d_details->baudclk,
-                                NULL, NULL, NULL, device_port) == KEYSPAN_BAUD_RATE_OK) {
-                p_priv->baud = baud_rate;
+        if (tty) {
+                cflag = tty->termios->c_cflag;
+                /* Baud rate calculation takes baud rate as an integer
+                   so other rates can be generated if desired. */
+                baud_rate = tty_get_baud_rate(tty);
+                /* If no match or invalid, leave as default */
+                if (baud_rate >= 0
+                    && d_details->calculate_baud_rate(baud_rate, d_details->baudclk,
+                                        NULL, NULL, NULL, device_port) == KEYSPAN_BAUD_RATE_OK) {
+                        p_priv->baud = baud_rate;
+                }
         }
-
         /* set CTS/RTS handshake etc. */
         p_priv->cflag = cflag;
         p_priv->flow_control = (cflag & CRTSCTS)? flow_cts: flow_none;
@@ -1301,7 +1276,8 @@ static inline void stop_urb(struct urb *urb)
                 usb_kill_urb(urb);
 }
 
-static void keyspan_close(struct usb_serial_port *port, struct file *filp)
+static void keyspan_close(struct tty_struct *tty,
+                        struct usb_serial_port *port, struct file *filp)
 {
         int                     i;
         struct usb_serial       *serial = port->serial;
@@ -1338,7 +1314,7 @@ static void keyspan_close(struct usb_serial_port *port, struct file *filp)
                         stop_urb(p_priv->out_urbs[i]);
                 }
         }
-        port->tty = NULL;
+        port->port.tty = NULL;
 }
 
         /* download the firmware to a pre-renumeration device */
@@ -2427,7 +2403,7 @@ static int keyspan_usa90_send_setup(struct usb_serial *serial,
         }
         /* Sending intermediate configs */
         else {
-                if (port->open_count)
+                if (port->port.count)
                         msg.portEnabled = 1;
                 msg.txBreak = (p_priv->break_on);
         }