TTY: switch tty_flip_buffer_push

Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.

Now, the one where most of tty_port_tty_get gets removed:
tty_flip_buffer_push.

IOW we also closed all the races in drivers not using tty_port_tty_get
at all yet.

Also we move tty_flip_buffer_push declaration from include/linux/tty.h
to include/linux/tty_flip.h to all others while we are changing it
anyway.

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

1 files changed, 16 insertions, 23 deletions

diff --git a/drivers/isdn/i4l/isdn_tty.c b/drivers/isdn/i4l/isdn_tty.c
index 9bb9986659e4..d8a7d8323414 100644
--- a/drivers/isdn/i4l/isdn_tty.c
+++ b/drivers/isdn/i4l/isdn_tty.c
@@ -63,16 +63,11 @@ isdn_tty_try_read(modem_info *info, struct sk_buff *skb)
         struct tty_port *port = &info->port;
         int c;
         int len;
-        struct tty_struct *tty;
         char last;
 
         if (!info->online)
                 return 0;
 
-        tty = port->tty;
-        if (!tty)
-                return 0;
-
         if (!(info->mcr & UART_MCR_RTS))
                 return 0;
 
@@ -110,7 +105,7 @@ isdn_tty_try_read(modem_info *info, struct sk_buff *skb)
                 tty_insert_flip_char(port, last, 0xFF);
         else
                 tty_insert_flip_char(port, last, TTY_NORMAL);
-        tty_flip_buffer_push(tty);
+        tty_flip_buffer_push(port);
         kfree_skb(skb);
 
         return 1;
@@ -127,7 +122,6 @@ isdn_tty_readmodem(void)
         int midx;
         int i;
         int r;
-        struct tty_struct *tty;
         modem_info *info;
 
         for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
@@ -145,20 +139,21 @@ isdn_tty_readmodem(void)
                 if ((info->vonline & 1) && (info->emu.vpar[1]))
                         isdn_audio_eval_silence(info);
 #endif
-                tty = info->port.tty;
-                if (tty) {
-                        if (info->mcr & UART_MCR_RTS) {
-                                /* CISCO AsyncPPP Hack */
-                                if (!(info->emu.mdmreg[REG_CPPP] & BIT_CPPP))
-                                        r = isdn_readbchan_tty(info->isdn_driver, info->isdn_channel, &info->port, 0);
-                                else
-                                        r = isdn_readbchan_tty(info->isdn_driver, info->isdn_channel, &info->port, 1);
-                                if (r)
-                                        tty_flip_buffer_push(tty);
-                        } else
-                                r = 1;
+                if (info->mcr & UART_MCR_RTS) {
+                        /* CISCO AsyncPPP Hack */
+                        if (!(info->emu.mdmreg[REG_CPPP] & BIT_CPPP))
+                                r = isdn_readbchan_tty(info->isdn_driver,
+                                                info->isdn_channel,
+                                                &info->port, 0);
+                        else
+                                r = isdn_readbchan_tty(info->isdn_driver,
+                                                info->isdn_channel,
+                                                &info->port, 1);
+                        if (r)
+                                tty_flip_buffer_push(&info->port);
                 } else
                         r = 1;
+
                 if (r) {
                         info->rcvsched = 0;
                         resched = 1;
@@ -2230,7 +2225,6 @@ isdn_tty_stat_callback(int i, isdn_ctrl *c)
 void
 isdn_tty_at_cout(char *msg, modem_info *info)
 {
-        struct tty_struct *tty;
         struct tty_port *port = &info->port;
         atemu *m = &info->emu;
         char *p;
@@ -2248,8 +2242,7 @@ isdn_tty_at_cout(char *msg, modem_info *info)
         l = strlen(msg);
 
         spin_lock_irqsave(&info->readlock, flags);
-        tty = port->tty;
-        if ((port->flags & ASYNC_CLOSING) || (!tty)) {
+        if (port->flags & ASYNC_CLOSING) {
                 spin_unlock_irqrestore(&info->readlock, flags);
                 return;
         }
@@ -2301,7 +2294,7 @@ isdn_tty_at_cout(char *msg, modem_info *info)
 
         } else {
                 spin_unlock_irqrestore(&info->readlock, flags);
-                tty_flip_buffer_push(tty);
+                tty_flip_buffer_push(port);
         }
 }