USB: tty: Prune uses of tty_request_room in the USB layer

We have lots of callers that do not need to do this in the first place.
Remove the calls as they both cost CPU and for big buffers can mess up the
multi-page allocation avoidance.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

24 files changed, 25 insertions, 79 deletions

diff --git a/drivers/usb/serial/ark3116.c b/drivers/usb/serial/ark3116.c
index 1f75fac81232..547c9448c28c 100644
--- a/drivers/usb/serial/ark3116.c
+++ b/drivers/usb/serial/ark3116.c
@@ -733,7 +733,6 @@ static void ark3116_read_bulk_callback(struct urb *urb)
 
                 tty = tty_port_tty_get(&port->port);
                 if (tty) {
-                        tty_buffer_request_room(tty, urb->actual_length + 1);
                         /* overrun is special, not associated with a char */
                         if (unlikely(lsr & UART_LSR_OE))
                                 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
diff --git a/drivers/usb/serial/cyberjack.c b/drivers/usb/serial/cyberjack.c
index 036f9996fe52..f744ab7a3b19 100644
--- a/drivers/usb/serial/cyberjack.c
+++ b/drivers/usb/serial/cyberjack.c
@@ -395,7 +395,6 @@ static void cyberjack_read_bulk_callback(struct urb *urb)
                 return;
         }
         if (urb->actual_length) {
-                tty_buffer_request_room(tty, urb->actual_length);
                 tty_insert_flip_string(tty, data, urb->actual_length);
                 tty_flip_buffer_push(tty);
         }
diff --git a/drivers/usb/serial/cypress_m8.c b/drivers/usb/serial/cypress_m8.c
index c349f790f856..3a5d57f89dee 100644
--- a/drivers/usb/serial/cypress_m8.c
+++ b/drivers/usb/serial/cypress_m8.c
@@ -1307,13 +1307,9 @@ static void cypress_read_int_callback(struct urb *urb)
                 spin_unlock_irqrestore(&priv->lock, flags);
 
         /* process read if there is data other than line status */
-        if (tty && (bytes > i)) {
-                bytes = tty_buffer_request_room(tty, bytes);
-                for (; i < bytes ; ++i) {
-                        dbg("pushing byte number %d - %d - %c", i, data[i],
-                                        data[i]);
-                        tty_insert_flip_char(tty, data[i], tty_flag);
-                }
+        if (tty && bytes > i) {
+                tty_insert_flip_string_fixed_flag(tty, data + i,
+                                bytes - i, tty_flag);
                 tty_flip_buffer_push(tty);
         }
 
diff --git a/drivers/usb/serial/digi_acceleport.c b/drivers/usb/serial/digi_acceleport.c
index 3b6348414c47..381722858424 100644
--- a/drivers/usb/serial/digi_acceleport.c
+++ b/drivers/usb/serial/digi_acceleport.c
@@ -1658,7 +1658,6 @@ static int digi_read_inb_callback(struct urb *urb)
         int port_status = ((unsigned char *)urb->transfer_buffer)[2];
         unsigned char *data = ((unsigned char *)urb->transfer_buffer) + 3;
         int flag, throttled;
-        int i;
         int status = urb->status;
 
         /* do not process callbacks on closed ports */
@@ -1705,17 +1704,9 @@ static int digi_read_inb_callback(struct urb *urb)
 
                 /* data length is len-1 (one byte of len is port_status) */
                 --len;
-
-                len = tty_buffer_request_room(tty, len);
                 if (len > 0) {
-                        /* Hot path */
-                        if (flag == TTY_NORMAL)
-                                tty_insert_flip_string(tty, data, len);
-                        else {
-                                for (i = 0; i < len; i++)
-                                        tty_insert_flip_char(tty,
-                                                                data[i], flag);
-                        }
+                        tty_insert_flip_string_fixed_flag(tty, data, len,
+                                                                        flag);
                         tty_flip_buffer_push(tty);
                 }
         }
diff --git a/drivers/usb/serial/empeg.c b/drivers/usb/serial/empeg.c
index d02e604e9cc4..5f740a1eacab 100644
--- a/drivers/usb/serial/empeg.c
+++ b/drivers/usb/serial/empeg.c
@@ -346,7 +346,6 @@ static void empeg_read_bulk_callback(struct urb *urb)
         tty = tty_port_tty_get(&port->port);
 
         if (urb->actual_length) {
-                tty_buffer_request_room(tty, urb->actual_length);
                 tty_insert_flip_string(tty, data, urb->actual_length);
                 tty_flip_buffer_push(tty);
                 bytes_in += urb->actual_length;
diff --git a/drivers/usb/serial/garmin_gps.c b/drivers/usb/serial/garmin_gps.c
index 6bbedfbb0fbc..a42b29a695b2 100644
--- a/drivers/usb/serial/garmin_gps.c
+++ b/drivers/usb/serial/garmin_gps.c
@@ -271,7 +271,6 @@ static void send_to_tty(struct usb_serial_port *port,
                 usb_serial_debug_data(debug, &port->dev,
                                         __func__, actual_length, data);
 
-                tty_buffer_request_room(tty, actual_length);
                 tty_insert_flip_string(tty, data, actual_length);
                 tty_flip_buffer_push(tty);
         }
diff --git a/drivers/usb/serial/io_edgeport.c b/drivers/usb/serial/io_edgeport.c
index 66fb58f427cd..3ef8df0ef888 100644
--- a/drivers/usb/serial/io_edgeport.c
+++ b/drivers/usb/serial/io_edgeport.c
@@ -2055,18 +2055,13 @@ static void edge_tty_recv(struct device *dev, struct tty_struct *tty,
 {
         int cnt;
 
-        do {
-                cnt = tty_buffer_request_room(tty, length);
-                if (cnt < length) {
-                        dev_err(dev, "%s - dropping data, %d bytes lost\n",
-                                        __func__, length - cnt);
-                        if (cnt == 0)
-                                break;
-                }
-                tty_insert_flip_string(tty, data, cnt);
-                data += cnt;
-                length -= cnt;
-        } while (length > 0);
+        cnt = tty_insert_flip_string(tty, data, length);
+        if (cnt < length) {
+                dev_err(dev, "%s - dropping data, %d bytes lost\n",
+                                __func__, length - cnt);
+        }
+        data += cnt;
+        length -= cnt;
 
         tty_flip_buffer_push(tty);
 }
diff --git a/drivers/usb/serial/io_ti.c b/drivers/usb/serial/io_ti.c
index 98e50456ad79..aa876f71f228 100644
--- a/drivers/usb/serial/io_ti.c
+++ b/drivers/usb/serial/io_ti.c
@@ -1820,7 +1820,6 @@ static void edge_tty_recv(struct device *dev, struct tty_struct *tty,
 {
         int queued;
 
-        tty_buffer_request_room(tty, length);
         queued = tty_insert_flip_string(tty, data, length);
         if (queued < length)
                 dev_err(dev, "%s - dropping data, %d bytes lost\n",
diff --git a/drivers/usb/serial/ipaq.c b/drivers/usb/serial/ipaq.c
index d6231c38813e..3fea9298eb15 100644
--- a/drivers/usb/serial/ipaq.c
+++ b/drivers/usb/serial/ipaq.c
@@ -747,7 +747,6 @@ static void ipaq_read_bulk_callback(struct urb *urb)
 
         tty = tty_port_tty_get(&port->port);
         if (tty && urb->actual_length) {
-                tty_buffer_request_room(tty, urb->actual_length);
                 tty_insert_flip_string(tty, data, urb->actual_length);
                 tty_flip_buffer_push(tty);
                 bytes_in += urb->actual_length;
diff --git a/drivers/usb/serial/ipw.c b/drivers/usb/serial/ipw.c
index c0afa7a219d7..e1d07840cee6 100644
--- a/drivers/usb/serial/ipw.c
+++ b/drivers/usb/serial/ipw.c
@@ -172,7 +172,6 @@ static void ipw_read_bulk_callback(struct urb *urb)
 
         tty = tty_port_tty_get(&port->port);
         if (tty && urb->actual_length) {
-                tty_buffer_request_room(tty, urb->actual_length);
                 tty_insert_flip_string(tty, data, urb->actual_length);
                 tty_flip_buffer_push(tty);
         }
diff --git a/drivers/usb/serial/ir-usb.c b/drivers/usb/serial/ir-usb.c
index fc2ab81a48d1..c3e5d506aead 100644
--- a/drivers/usb/serial/ir-usb.c
+++ b/drivers/usb/serial/ir-usb.c
@@ -462,10 +462,8 @@ static void ir_read_bulk_callback(struct urb *urb)
                 usb_serial_debug_data(debug, &port->dev, __func__,
                                                 urb->actual_length, data);
                 tty = tty_port_tty_get(&port->port);
-                if (tty_buffer_request_room(tty, urb->actual_length - 1)) {
-                        tty_insert_flip_string(tty, data+1, urb->actual_length - 1);
-                        tty_flip_buffer_push(tty);
-                }
+                tty_insert_flip_string(tty, data+1, urb->actual_length - 1);
+                tty_flip_buffer_push(tty);
                 tty_kref_put(tty);
 
                 /*
diff --git a/drivers/usb/serial/kl5kusb105.c b/drivers/usb/serial/kl5kusb105.c
index 2dbe22ae50fc..8eef91ba4b1c 100644
--- a/drivers/usb/serial/kl5kusb105.c
+++ b/drivers/usb/serial/kl5kusb105.c
@@ -699,7 +699,6 @@ static void klsi_105_read_bulk_callback(struct urb *urb)
                         bytes_sent = urb->actual_length - 2;
                 }
 
-                tty_buffer_request_room(tty, bytes_sent);
                 tty_insert_flip_string(tty, data + 2, bytes_sent);
                 tty_flip_buffer_push(tty);
                 tty_kref_put(tty);
diff --git a/drivers/usb/serial/kobil_sct.c b/drivers/usb/serial/kobil_sct.c
index fc7855388e27..c113a2a0e10c 100644
--- a/drivers/usb/serial/kobil_sct.c
+++ b/drivers/usb/serial/kobil_sct.c
@@ -388,7 +388,6 @@ static void kobil_read_int_callback(struct urb *urb)
                 */
                 /* END DEBUG */
 
-                tty_buffer_request_room(tty, urb->actual_length);
                 tty_insert_flip_string(tty, data, urb->actual_length);
                 tty_flip_buffer_push(tty);
         }
diff --git a/drivers/usb/serial/mos7720.c b/drivers/usb/serial/mos7720.c
index 546b29f73c2c..0d47f2c4d59f 100644
--- a/drivers/usb/serial/mos7720.c
+++ b/drivers/usb/serial/mos7720.c
@@ -290,7 +290,6 @@ static void mos7720_bulk_in_callback(struct urb *urb)
 
         tty = tty_port_tty_get(&port->port);
         if (tty && urb->actual_length) {
-                tty_buffer_request_room(tty, urb->actual_length);
                 tty_insert_flip_string(tty, data, urb->actual_length);
                 tty_flip_buffer_push(tty);
         }
diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c
index c89a89c6394e..2fda1c0182b7 100644
--- a/drivers/usb/serial/mos7840.c
+++ b/drivers/usb/serial/mos7840.c
@@ -764,7 +764,6 @@ static void mos7840_bulk_in_callback(struct urb *urb)
         if (urb->actual_length) {
                 tty = tty_port_tty_get(&mos7840_port->port->port);
                 if (tty) {
-                        tty_buffer_request_room(tty, urb->actual_length);
                         tty_insert_flip_string(tty, data, urb->actual_length);
                         dbg(" %s ", data);
                         tty_flip_buffer_push(tty);
diff --git a/drivers/usb/serial/navman.c b/drivers/usb/serial/navman.c
index efa61bcd3297..04a6cbbed2c0 100644
--- a/drivers/usb/serial/navman.c
+++ b/drivers/usb/serial/navman.c
@@ -66,7 +66,6 @@ static void navman_read_int_callback(struct urb *urb)
 
         tty = tty_port_tty_get(&port->port);
         if (tty && urb->actual_length) {
-                tty_buffer_request_room(tty, urb->actual_length);
                 tty_insert_flip_string(tty, data, urb->actual_length);
                 tty_flip_buffer_push(tty);
         }
diff --git a/drivers/usb/serial/opticon.c b/drivers/usb/serial/opticon.c
index 773286672ec9..f37476e22684 100644
--- a/drivers/usb/serial/opticon.c
+++ b/drivers/usb/serial/opticon.c
@@ -55,7 +55,6 @@ static void opticon_bulk_callback(struct urb *urb)
         int status = urb->status;
         struct tty_struct *tty;
         int result;
-        int available_room = 0;
         int data_length;
 
         dbg("%s - port %d", __func__, port->number);
@@ -96,13 +95,9 @@ static void opticon_bulk_callback(struct urb *urb)
                         /* real data, send it to the tty layer */
                         tty = tty_port_tty_get(&port->port);
                         if (tty) {
-                                available_room = tty_buffer_request_room(tty,
-                                                                data_length);
-                                if (available_room) {
-                                        tty_insert_flip_string(tty, data,
-                                                               available_room);
-                                        tty_flip_buffer_push(tty);
-                                }
+                                tty_insert_flip_string(tty, data,
+                                                               data_length);
+                                tty_flip_buffer_push(tty);
                                 tty_kref_put(tty);
                         }
                 } else {
diff --git a/drivers/usb/serial/option.c b/drivers/usb/serial/option.c
index f6646b30f954..68c7457a98ae 100644
--- a/drivers/usb/serial/option.c
+++ b/drivers/usb/serial/option.c
@@ -964,7 +964,6 @@ static void option_indat_callback(struct urb *urb)
         } else {
                 tty = tty_port_tty_get(&port->port);
                 if (urb->actual_length) {
-                        tty_buffer_request_room(tty, urb->actual_length);
                         tty_insert_flip_string(tty, data, urb->actual_length);
                         tty_flip_buffer_push(tty);
                 } else 
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index 767000c70149..a3e5a56dc066 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -1042,7 +1042,6 @@ static void pl2303_push_data(struct tty_struct *tty,
                 tty_flag = TTY_FRAME;
         dbg("%s - tty_flag = %d", __func__, tty_flag);
 
-        tty_buffer_request_room(tty, urb->actual_length + 1);
         /* overrun is special, not associated with a char */
         if (line_status & UART_OVERRUN_ERROR)
                 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
diff --git a/drivers/usb/serial/sierra.c b/drivers/usb/serial/sierra.c
index fcec46603558..c012e51665bd 100644
--- a/drivers/usb/serial/sierra.c
+++ b/drivers/usb/serial/sierra.c
@@ -595,8 +595,6 @@ static void sierra_indat_callback(struct urb *urb)
                 if (urb->actual_length) {
                         tty = tty_port_tty_get(&port->port);
                         if (tty) {
-                                tty_buffer_request_room(tty,
-                                        urb->actual_length);
                                 tty_insert_flip_string(tty, data,
                                         urb->actual_length);
                                 tty_flip_buffer_push(tty);
diff --git a/drivers/usb/serial/spcp8x5.c b/drivers/usb/serial/spcp8x5.c
index 067e95ad2987..cf508e26f1c6 100644
--- a/drivers/usb/serial/spcp8x5.c
+++ b/drivers/usb/serial/spcp8x5.c
@@ -677,7 +677,6 @@ static void spcp8x5_read_bulk_callback(struct urb *urb)
         struct tty_struct *tty;
         unsigned char *data = urb->transfer_buffer;
         unsigned long flags;
-        int i;
         int result = urb->status;
         u8 status;
         char tty_flag;
@@ -726,12 +725,11 @@ static void spcp8x5_read_bulk_callback(struct urb *urb)
 
         tty = tty_port_tty_get(&port->port);
         if (tty && urb->actual_length) {
-                tty_buffer_request_room(tty, urb->actual_length + 1);
                 /* overrun is special, not associated with a char */
                 if (status & UART_OVERRUN_ERROR)
                         tty_insert_flip_char(tty, 0, TTY_OVERRUN);
-                for (i = 0; i < urb->actual_length; ++i)
-                        tty_insert_flip_char(tty, data[i], tty_flag);
+                tty_insert_flip_string_fixed_flag(tty, data,
+                                                urb->actual_length, tty_flag);
                 tty_flip_buffer_push(tty);
         }
         tty_kref_put(tty);
diff --git a/drivers/usb/serial/symbolserial.c b/drivers/usb/serial/symbolserial.c
index 1a76bc5261e9..72398888858f 100644
--- a/drivers/usb/serial/symbolserial.c
+++ b/drivers/usb/serial/symbolserial.c
@@ -51,7 +51,6 @@ static void symbol_int_callback(struct urb *urb)
         int status = urb->status;
         struct tty_struct *tty;
         int result;
-        int available_room = 0;
         int data_length;
 
         dbg("%s - port %d", __func__, port->number);
@@ -89,13 +88,8 @@ static void symbol_int_callback(struct urb *urb)
                  */
                 tty = tty_port_tty_get(&port->port);
                 if (tty) {
-                        available_room = tty_buffer_request_room(tty,
-                                                        data_length);
-                        if (available_room) {
-                                tty_insert_flip_string(tty, &data[1],
-                                                       available_room);
-                                tty_flip_buffer_push(tty);
-                        }
+                        tty_insert_flip_string(tty, &data[1], data_length);
+                        tty_flip_buffer_push(tty);
                         tty_kref_put(tty);
                 }
         } else {
diff --git a/drivers/usb/serial/ti_usb_3410_5052.c b/drivers/usb/serial/ti_usb_3410_5052.c
index 1e9dc8821698..0afe5c71c17e 100644
--- a/drivers/usb/serial/ti_usb_3410_5052.c
+++ b/drivers/usb/serial/ti_usb_3410_5052.c
@@ -1271,14 +1271,13 @@ static void ti_recv(struct device *dev, struct tty_struct *tty,
         int cnt;
 
         do {
-                cnt = tty_buffer_request_room(tty, length);
+                cnt = tty_insert_flip_string(tty, data, length);
                 if (cnt < length) {
                         dev_err(dev, "%s - dropping data, %d bytes lost\n",
                                                 __func__, length - cnt);
                         if (cnt == 0)
                                 break;
                 }
-                tty_insert_flip_string(tty, data, cnt);
                 tty_flip_buffer_push(tty);
                 data += cnt;
                 length -= cnt;
diff --git a/drivers/usb/serial/visor.c b/drivers/usb/serial/visor.c
index 4f7945e672cc..094942707c7d 100644
--- a/drivers/usb/serial/visor.c
+++ b/drivers/usb/serial/visor.c
@@ -503,13 +503,9 @@ static void visor_read_bulk_callback(struct urb *urb)
         if (urb->actual_length) {
                 tty = tty_port_tty_get(&port->port);
                 if (tty) {
-                        available_room = tty_buffer_request_room(tty,
-                                                        urb->actual_length);
-                        if (available_room) {
-                                tty_insert_flip_string(tty, data,
-                                                        available_room);
-                                tty_flip_buffer_push(tty);
-                        }
+                        tty_insert_flip_string(tty, data,
+                                                urb->actual_length);
+                        tty_flip_buffer_push(tty);
                         tty_kref_put(tty);
                 }
                 spin_lock(&priv->lock);