tty: make receive_buf() return the amout of bytes received
it makes it simpler to keep track of the amount of
bytes received and simplifies how flush_to_ldisc counts
the remaining bytes. It also fixes a bug of lost bytes
on n_tty when flushing too many bytes via the USB
serial gadget driver.
Tested-by: Stefan Bigler <stefan.bigler@keymile.com>
Tested-by: Toby Gray <toby.gray@realvnc.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/net/caif/caif_serial.c b/drivers/net/caif/caif_serial.c
index 3df0c0f..73c7e03 100644
--- a/drivers/net/caif/caif_serial.c
+++ b/drivers/net/caif/caif_serial.c
@@ -167,8 +167,8 @@
#endif
-static void ldisc_receive(struct tty_struct *tty, const u8 *data,
- char *flags, int count)
+static unsigned int ldisc_receive(struct tty_struct *tty,
+ const u8 *data, char *flags, int count)
{
struct sk_buff *skb = NULL;
struct ser_device *ser;
@@ -215,6 +215,8 @@
} else
++ser->dev->stats.rx_dropped;
update_tty_status(ser);
+
+ return count;
}
static int handle_tx(struct ser_device *ser)
diff --git a/drivers/net/can/slcan.c b/drivers/net/can/slcan.c
index b423965..c600954 100644
--- a/drivers/net/can/slcan.c
+++ b/drivers/net/can/slcan.c
@@ -425,16 +425,17 @@
* in parallel
*/
-static void slcan_receive_buf(struct tty_struct *tty,
+static unsigned int slcan_receive_buf(struct tty_struct *tty,
const unsigned char *cp, char *fp, int count)
{
struct slcan *sl = (struct slcan *) tty->disc_data;
+ int bytes = count;
if (!sl || sl->magic != SLCAN_MAGIC || !netif_running(sl->dev))
- return;
+ return -ENODEV;
/* Read the characters out of the buffer */
- while (count--) {
+ while (bytes--) {
if (fp && *fp++) {
if (!test_and_set_bit(SLF_ERROR, &sl->flags))
sl->dev->stats.rx_errors++;
@@ -443,6 +444,8 @@
}
slcan_unesc(sl, *cp++);
}
+
+ return count;
}
/************************************
diff --git a/drivers/net/hamradio/6pack.c b/drivers/net/hamradio/6pack.c
index 3e5d0b6..9920896 100644
--- a/drivers/net/hamradio/6pack.c
+++ b/drivers/net/hamradio/6pack.c
@@ -456,7 +456,7 @@
* a block of 6pack data has been received, which can now be decapsulated
* and sent on to some IP layer for further processing.
*/
-static void sixpack_receive_buf(struct tty_struct *tty,
+static unsigned int sixpack_receive_buf(struct tty_struct *tty,
const unsigned char *cp, char *fp, int count)
{
struct sixpack *sp;
@@ -464,11 +464,11 @@
int count1;
if (!count)
- return;
+ return 0;
sp = sp_get(tty);
if (!sp)
- return;
+ return -ENODEV;
memcpy(buf, cp, count < sizeof(buf) ? count : sizeof(buf));
@@ -487,6 +487,8 @@
sp_put(sp);
tty_unthrottle(tty);
+
+ return count1;
}
/*
diff --git a/drivers/net/hamradio/mkiss.c b/drivers/net/hamradio/mkiss.c
index 4c62839..0e4f235 100644
--- a/drivers/net/hamradio/mkiss.c
+++ b/drivers/net/hamradio/mkiss.c
@@ -923,13 +923,14 @@
* a block of data has been received, which can now be decapsulated
* and sent on to the AX.25 layer for further processing.
*/
-static void mkiss_receive_buf(struct tty_struct *tty, const unsigned char *cp,
- char *fp, int count)
+static unsigned int mkiss_receive_buf(struct tty_struct *tty,
+ const unsigned char *cp, char *fp, int count)
{
struct mkiss *ax = mkiss_get(tty);
+ int bytes = count;
if (!ax)
- return;
+ return -ENODEV;
/*
* Argh! mtu change time! - costs us the packet part received
@@ -939,7 +940,7 @@
ax_changedmtu(ax);
/* Read the characters out of the buffer */
- while (count--) {
+ while (bytes--) {
if (fp != NULL && *fp++) {
if (!test_and_set_bit(AXF_ERROR, &ax->flags))
ax->dev->stats.rx_errors++;
@@ -952,6 +953,8 @@
mkiss_put(ax);
tty_unthrottle(tty);
+
+ return count;
}
/*
diff --git a/drivers/net/irda/irtty-sir.c b/drivers/net/irda/irtty-sir.c
index 3352b24..035861d 100644
--- a/drivers/net/irda/irtty-sir.c
+++ b/drivers/net/irda/irtty-sir.c
@@ -216,23 +216,23 @@
* usbserial: urb-complete-interrupt / softint
*/
-static void irtty_receive_buf(struct tty_struct *tty, const unsigned char *cp,
- char *fp, int count)
+static unsigned int irtty_receive_buf(struct tty_struct *tty,
+ const unsigned char *cp, char *fp, int count)
{
struct sir_dev *dev;
struct sirtty_cb *priv = tty->disc_data;
int i;
- IRDA_ASSERT(priv != NULL, return;);
- IRDA_ASSERT(priv->magic == IRTTY_MAGIC, return;);
+ IRDA_ASSERT(priv != NULL, return -ENODEV;);
+ IRDA_ASSERT(priv->magic == IRTTY_MAGIC, return -EINVAL;);
if (unlikely(count==0)) /* yes, this happens */
- return;
+ return 0;
dev = priv->dev;
if (!dev) {
IRDA_WARNING("%s(), not ready yet!\n", __func__);
- return;
+ return -ENODEV;
}
for (i = 0; i < count; i++) {
@@ -242,11 +242,13 @@
if (fp && *fp++) {
IRDA_DEBUG(0, "Framing or parity error!\n");
sirdev_receive(dev, NULL, 0); /* notify sir_dev (updating stats) */
- return;
+ return -EINVAL;
}
}
sirdev_receive(dev, cp, count);
+
+ return count;
}
/*
diff --git a/drivers/net/ppp_async.c b/drivers/net/ppp_async.c
index a1b82c9..53872d7 100644
--- a/drivers/net/ppp_async.c
+++ b/drivers/net/ppp_async.c
@@ -340,7 +340,7 @@
}
/* May sleep, don't call from interrupt level or with interrupts disabled */
-static void
+static unsigned int
ppp_asynctty_receive(struct tty_struct *tty, const unsigned char *buf,
char *cflags, int count)
{
@@ -348,7 +348,7 @@
unsigned long flags;
if (!ap)
- return;
+ return -ENODEV;
spin_lock_irqsave(&ap->recv_lock, flags);
ppp_async_input(ap, buf, cflags, count);
spin_unlock_irqrestore(&ap->recv_lock, flags);
@@ -356,6 +356,8 @@
tasklet_schedule(&ap->tsk);
ap_put(ap);
tty_unthrottle(tty);
+
+ return count;
}
static void
diff --git a/drivers/net/ppp_synctty.c b/drivers/net/ppp_synctty.c
index 2573f52..0815790 100644
--- a/drivers/net/ppp_synctty.c
+++ b/drivers/net/ppp_synctty.c
@@ -381,7 +381,7 @@
}
/* May sleep, don't call from interrupt level or with interrupts disabled */
-static void
+static unsigned int
ppp_sync_receive(struct tty_struct *tty, const unsigned char *buf,
char *cflags, int count)
{
@@ -389,7 +389,7 @@
unsigned long flags;
if (!ap)
- return;
+ return -ENODEV;
spin_lock_irqsave(&ap->recv_lock, flags);
ppp_sync_input(ap, buf, cflags, count);
spin_unlock_irqrestore(&ap->recv_lock, flags);
@@ -397,6 +397,8 @@
tasklet_schedule(&ap->tsk);
sp_put(ap);
tty_unthrottle(tty);
+
+ return count;
}
static void
diff --git a/drivers/net/slip.c b/drivers/net/slip.c
index 86cbb9e..86718d3 100644
--- a/drivers/net/slip.c
+++ b/drivers/net/slip.c
@@ -670,16 +670,17 @@
* in parallel
*/
-static void slip_receive_buf(struct tty_struct *tty, const unsigned char *cp,
- char *fp, int count)
+static unsigned int slip_receive_buf(struct tty_struct *tty,
+ const unsigned char *cp, char *fp, int count)
{
struct slip *sl = tty->disc_data;
+ int bytes = count;
if (!sl || sl->magic != SLIP_MAGIC || !netif_running(sl->dev))
- return;
+ return -ENODEV;
/* Read the characters out of the buffer */
- while (count--) {
+ while (bytes--) {
if (fp && *fp++) {
if (!test_and_set_bit(SLF_ERROR, &sl->flags))
sl->dev->stats.rx_errors++;
@@ -693,6 +694,8 @@
#endif
slip_unesc(sl, *cp++);
}
+
+ return count;
}
/************************************
diff --git a/drivers/net/wan/x25_asy.c b/drivers/net/wan/x25_asy.c
index 24297b2..40398bf 100644
--- a/drivers/net/wan/x25_asy.c
+++ b/drivers/net/wan/x25_asy.c
@@ -517,17 +517,18 @@
* and sent on to some IP layer for further processing.
*/
-static void x25_asy_receive_buf(struct tty_struct *tty,
+static unsigned int x25_asy_receive_buf(struct tty_struct *tty,
const unsigned char *cp, char *fp, int count)
{
struct x25_asy *sl = tty->disc_data;
+ int bytes = count;
if (!sl || sl->magic != X25_ASY_MAGIC || !netif_running(sl->dev))
return;
/* Read the characters out of the buffer */
- while (count--) {
+ while (bytes--) {
if (fp && *fp++) {
if (!test_and_set_bit(SLF_ERROR, &sl->flags))
sl->dev->stats.rx_errors++;
@@ -536,6 +537,8 @@
}
x25_asy_unesc(sl, *cp++);
}
+
+ return count;
}
/*