Commit b1c43f82 authored by Felipe Balbi's avatar Felipe Balbi Committed by Greg Kroah-Hartman

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: default avatarStefan Bigler <stefan.bigler@keymile.com>
Tested-by: default avatarToby Gray <toby.gray@realvnc.com>
Signed-off-by: default avatarFelipe Balbi <balbi@ti.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent e9a470f4
......@@ -357,22 +357,26 @@ static void hci_uart_tty_wakeup(struct tty_struct *tty)
*
* Return Value: None
*/
static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data, char *flags, int count)
static unsigned int hci_uart_tty_receive(struct tty_struct *tty,
const u8 *data, char *flags, int count)
{
struct hci_uart *hu = (void *)tty->disc_data;
int received;
if (!hu || tty != hu->tty)
return;
return -ENODEV;
if (!test_bit(HCI_UART_PROTO_SET, &hu->flags))
return;
return -EINVAL;
spin_lock(&hu->rx_lock);
hu->proto->recv(hu, (void *) data, count);
received = hu->proto->recv(hu, (void *) data, count);
hu->hdev->stat.byte_rx += count;
spin_unlock(&hu->rx_lock);
tty_unthrottle(tty);
return received;
}
static int hci_uart_register_dev(struct hci_uart *hu)
......
......@@ -120,17 +120,21 @@ static void serport_ldisc_close(struct tty_struct *tty)
* 'interrupt' routine.
*/
static void serport_ldisc_receive(struct tty_struct *tty, const unsigned char *cp, char *fp, int count)
static unsigned int serport_ldisc_receive(struct tty_struct *tty,
const unsigned char *cp, char *fp, int count)
{
struct serport *serport = (struct serport*) tty->disc_data;
unsigned long flags;
unsigned int ch_flags;
int ret = 0;
int i;
spin_lock_irqsave(&serport->lock, flags);
if (!test_bit(SERPORT_ACTIVE, &serport->flags))
if (!test_bit(SERPORT_ACTIVE, &serport->flags)) {
ret = -EINVAL;
goto out;
}
for (i = 0; i < count; i++) {
switch (fp[i]) {
......@@ -152,6 +156,8 @@ static void serport_ldisc_receive(struct tty_struct *tty, const unsigned char *c
out:
spin_unlock_irqrestore(&serport->lock, flags);
return ret == 0 ? count : ret;
}
/*
......
......@@ -674,7 +674,7 @@ gigaset_tty_ioctl(struct tty_struct *tty, struct file *file,
* cflags buffer containing error flags for received characters (ignored)
* count number of received characters
*/
static void
static unsigned int
gigaset_tty_receive(struct tty_struct *tty, const unsigned char *buf,
char *cflags, int count)
{
......@@ -683,12 +683,12 @@ gigaset_tty_receive(struct tty_struct *tty, const unsigned char *buf,
struct inbuf_t *inbuf;
if (!cs)
return;
return -ENODEV;
inbuf = cs->inbuf;
if (!inbuf) {
dev_err(cs->dev, "%s: no inbuf\n", __func__);
cs_put(cs);
return;
return -EINVAL;
}
tail = inbuf->tail;
......@@ -725,6 +725,8 @@ gigaset_tty_receive(struct tty_struct *tty, const unsigned char *buf,
gig_dbg(DEBUG_INTR, "%s-->BH", __func__);
gigaset_schedule_event(cs);
cs_put(cs);
return count;
}
/*
......
......@@ -744,8 +744,8 @@ static void st_tty_close(struct tty_struct *tty)
pr_debug("%s: done ", __func__);
}
static void st_tty_receive(struct tty_struct *tty, const unsigned char *data,
char *tty_flags, int count)
static unsigned int st_tty_receive(struct tty_struct *tty,
const unsigned char *data, char *tty_flags, int count)
{
#ifdef VERBOSE
print_hex_dump(KERN_DEBUG, ">in>", DUMP_PREFIX_NONE,
......@@ -758,6 +758,8 @@ static void st_tty_receive(struct tty_struct *tty, const unsigned char *data,
*/
st_recv(tty->disc_data, data, count);
pr_debug("done %s", __func__);
return count;
}
/* wake-up function called in from the TTY layer
......
......@@ -167,8 +167,8 @@ static inline void debugfs_tx(struct ser_device *ser, const u8 *data, int size)
#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 @@ static void ldisc_receive(struct tty_struct *tty, const u8 *data,
} else
++ser->dev->stats.rx_dropped;
update_tty_status(ser);
return count;
}
static int handle_tx(struct ser_device *ser)
......
......@@ -425,16 +425,17 @@ static void slc_setup(struct net_device *dev)
* 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 @@ static void slcan_receive_buf(struct tty_struct *tty,
}
slcan_unesc(sl, *cp++);
}
return count;
}
/************************************
......
......@@ -456,7 +456,7 @@ static void sixpack_write_wakeup(struct tty_struct *tty)
* 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 @@ static void sixpack_receive_buf(struct tty_struct *tty,
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 @@ static void sixpack_receive_buf(struct tty_struct *tty,
sp_put(sp);
tty_unthrottle(tty);
return count1;
}
/*
......
......@@ -923,13 +923,14 @@ static long mkiss_compat_ioctl(struct tty_struct *tty, struct file *file,
* 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 @@ static void mkiss_receive_buf(struct tty_struct *tty, const unsigned char *cp,
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 @@ static void mkiss_receive_buf(struct tty_struct *tty, const unsigned char *cp,
mkiss_put(ax);
tty_unthrottle(tty);
return count;
}
/*
......
......@@ -216,23 +216,23 @@ static int irtty_do_write(struct sir_dev *dev, const unsigned char *ptr, size_t
* 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 @@ static void irtty_receive_buf(struct tty_struct *tty, const unsigned char *cp,
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;
}
/*
......
......@@ -340,7 +340,7 @@ ppp_asynctty_poll(struct tty_struct *tty, struct file *file, poll_table *wait)
}
/* 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 @@ ppp_asynctty_receive(struct tty_struct *tty, const unsigned char *buf,
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 @@ ppp_asynctty_receive(struct tty_struct *tty, const unsigned char *buf,
tasklet_schedule(&ap->tsk);
ap_put(ap);
tty_unthrottle(tty);
return count;
}
static void
......
......@@ -381,7 +381,7 @@ ppp_sync_poll(struct tty_struct *tty, struct file *file, poll_table *wait)
}
/* 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 @@ ppp_sync_receive(struct tty_struct *tty, const unsigned char *buf,
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 @@ ppp_sync_receive(struct tty_struct *tty, const unsigned char *buf,
tasklet_schedule(&ap->tsk);
sp_put(ap);
tty_unthrottle(tty);
return count;
}
static void
......
......@@ -670,16 +670,17 @@ static void sl_setup(struct net_device *dev)
* 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 @@ static void slip_receive_buf(struct tty_struct *tty, const unsigned char *cp,
#endif
slip_unesc(sl, *cp++);
}
return count;
}
/************************************
......
......@@ -517,17 +517,18 @@ static int x25_asy_close(struct net_device *dev)
* 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 @@ static void x25_asy_receive_buf(struct tty_struct *tty,
}
x25_asy_unesc(sl, *cp++);
}
return count;
}
/*
......
......@@ -2138,8 +2138,8 @@ static void gsmld_detach_gsm(struct tty_struct *tty, struct gsm_mux *gsm)
gsm->tty = NULL;
}
static void gsmld_receive_buf(struct tty_struct *tty, const unsigned char *cp,
char *fp, int count)
static unsigned int gsmld_receive_buf(struct tty_struct *tty,
const unsigned char *cp, char *fp, int count)
{
struct gsm_mux *gsm = tty->disc_data;
const unsigned char *dp;
......@@ -2173,6 +2173,8 @@ static void gsmld_receive_buf(struct tty_struct *tty, const unsigned char *cp,
}
/* FASYNC if needed ? */
/* If clogged call tty_throttle(tty); */
return count;
}
/**
......
......@@ -188,8 +188,8 @@ static unsigned int n_hdlc_tty_poll(struct tty_struct *tty, struct file *filp,
poll_table *wait);
static int n_hdlc_tty_open(struct tty_struct *tty);
static void n_hdlc_tty_close(struct tty_struct *tty);
static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *cp,
char *fp, int count);
static unsigned int n_hdlc_tty_receive(struct tty_struct *tty,
const __u8 *cp, char *fp, int count);
static void n_hdlc_tty_wakeup(struct tty_struct *tty);
#define bset(p,b) ((p)[(b) >> 5] |= (1 << ((b) & 0x1f)))
......@@ -509,8 +509,8 @@ static void n_hdlc_tty_wakeup(struct tty_struct *tty)
* Called by tty low level driver when receive data is available. Data is
* interpreted as one HDLC frame.
*/
static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data,
char *flags, int count)
static unsigned int n_hdlc_tty_receive(struct tty_struct *tty,
const __u8 *data, char *flags, int count)
{
register struct n_hdlc *n_hdlc = tty2n_hdlc (tty);
register struct n_hdlc_buf *buf;
......@@ -521,20 +521,20 @@ static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data,
/* This can happen if stuff comes in on the backup tty */
if (!n_hdlc || tty != n_hdlc->tty)
return;
return -ENODEV;
/* verify line is using HDLC discipline */
if (n_hdlc->magic != HDLC_MAGIC) {
printk("%s(%d) line not using HDLC discipline\n",
__FILE__,__LINE__);
return;
return -EINVAL;
}
if ( count>maxframe ) {
if (debuglevel >= DEBUG_LEVEL_INFO)
printk("%s(%d) rx count>maxframesize, data discarded\n",
__FILE__,__LINE__);
return;
return -EINVAL;
}
/* get a free HDLC buffer */
......@@ -550,7 +550,7 @@ static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data,
if (debuglevel >= DEBUG_LEVEL_INFO)
printk("%s(%d) no more rx buffers, data discarded\n",
__FILE__,__LINE__);
return;
return -EINVAL;
}
/* copy received data to HDLC buffer */
......@@ -565,6 +565,8 @@ static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data,
if (n_hdlc->tty->fasync != NULL)
kill_fasync (&n_hdlc->tty->fasync, SIGIO, POLL_IN);
return count;
} /* end of n_hdlc_tty_receive() */
/**
......
......@@ -139,8 +139,8 @@ static int r3964_ioctl(struct tty_struct *tty, struct file *file,
static void r3964_set_termios(struct tty_struct *tty, struct ktermios *old);
static unsigned int r3964_poll(struct tty_struct *tty, struct file *file,
struct poll_table_struct *wait);
static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp,
char *fp, int count);
static unsigned int r3964_receive_buf(struct tty_struct *tty,
const unsigned char *cp, char *fp, int count);
static struct tty_ldisc_ops tty_ldisc_N_R3964 = {
.owner = THIS_MODULE,
......@@ -1239,8 +1239,8 @@ static unsigned int r3964_poll(struct tty_struct *tty, struct file *file,
return result;
}
static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp,
char *fp, int count)
static unsigned int r3964_receive_buf(struct tty_struct *tty,
const unsigned char *cp, char *fp, int count)
{
struct r3964_info *pInfo = tty->disc_data;
const unsigned char *p;
......@@ -1257,6 +1257,8 @@ static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp,
}
}
return count;
}
MODULE_LICENSE("GPL");
......
......@@ -81,38 +81,6 @@ static inline int tty_put_user(struct tty_struct *tty, unsigned char x,
return put_user(x, ptr);
}
/**
* n_tty_set__room - receive space
* @tty: terminal
*
* Called by the driver to find out how much data it is
* permitted to feed to the line discipline without any being lost
* and thus to manage flow control. Not serialized. Answers for the
* "instant".
*/
static void n_tty_set_room(struct tty_struct *tty)
{
/* tty->read_cnt is not read locked ? */
int left = N_TTY_BUF_SIZE - tty->read_cnt - 1;
int old_left;
/*
* If we are doing input canonicalization, and there are no
* pending newlines, let characters through without limit, so
* that erase characters will be handled. Other excess
* characters will be beeped.
*/
if (left <= 0)
left = tty->icanon && !tty->canon_data;
old_left = tty->receive_room;
tty->receive_room = left;
/* Did this open up the receive buffer? We may need to flip */
if (left && !old_left)
schedule_work(&tty->buf.work);
}
static void put_tty_queue_nolock(unsigned char c, struct tty_struct *tty)
{
if (tty->read_cnt < N_TTY_BUF_SIZE) {
......@@ -184,7 +152,6 @@ static void reset_buffer_flags(struct tty_struct *tty)
tty->canon_head = tty->canon_data = tty->erasing = 0;
memset(&tty->read_flags, 0, sizeof tty->read_flags);
n_tty_set_room(tty);
check_unthrottle(tty);
}
......@@ -1360,17 +1327,19 @@ static void n_tty_write_wakeup(struct tty_struct *tty)
* calls one at a time and in order (or using flush_to_ldisc)
*/
static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp,
char *fp, int count)
static unsigned int n_tty_receive_buf(struct tty_struct *tty,
const unsigned char *cp, char *fp, int count)
{
const unsigned char *p;
char *f, flags = TTY_NORMAL;
int i;
char buf[64];
unsigned long cpuflags;
int left;
int ret = 0;
if (!tty->read_buf)
return;
return 0;
if (tty->real_raw) {
spin_lock_irqsave(&tty->read_lock, cpuflags);
......@@ -1380,6 +1349,7 @@ static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp,
memcpy(tty->read_buf + tty->read_head, cp, i);
tty->read_head = (tty->read_head + i) & (N_TTY_BUF_SIZE-1);
tty->read_cnt += i;
ret += i;
cp += i;
count -= i;
......@@ -1389,8 +1359,10 @@ static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp,
memcpy(tty->read_buf + tty->read_head, cp, i);
tty->read_head = (tty->read_head + i) & (N_TTY_BUF_SIZE-1);
tty->read_cnt += i;
ret += i;
spin_unlock_irqrestore(&tty->read_lock, cpuflags);
} else {
ret = count;
for (i = count, p = cp, f = fp; i; i--, p++) {
if (f)
flags = *f++;
......@@ -1418,8 +1390,6 @@ static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp,
tty->ops->flush_chars(tty);
}
n_tty_set_room(tty);
if ((!tty->icanon && (tty->read_cnt >= tty->minimum_to_wake)) ||
L_EXTPROC(tty)) {
kill_fasync(&tty->fasync, SIGIO, POLL_IN);
......@@ -1432,8 +1402,12 @@ static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp,
* mode. We don't want to throttle the driver if we're in
* canonical mode and don't have a newline yet!
*/
if (tty->receive_room < TTY_THRESHOLD_THROTTLE)
left = N_TTY_BUF_SIZE - tty->read_cnt - 1;
if (left < TTY_THRESHOLD_THROTTLE)
tty_throttle(tty);
return ret;
}
int is_ignored(int sig)
......@@ -1477,7 +1451,6 @@ static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
if (test_bit(TTY_HW_COOK_IN, &tty->flags)) {
tty->raw = 1;
tty->real_raw = 1;
n_tty_set_room(tty);
return;
}
if (I_ISTRIP(tty) || I_IUCLC(tty) || I_IGNCR(tty) ||
......@@ -1530,7 +1503,6 @@ static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
else
tty->real_raw = 0;
}
n_tty_set_room(tty);
/* The termios change make the tty ready for I/O */
wake_up_interruptible(&tty->write_wait);
wake_up_interruptible(&tty->read_wait);
......@@ -1812,8 +1784,6 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
retval = -ERESTARTSYS;
break;
}
/* FIXME: does n_tty_set_room need locking ? */
n_tty_set_room(tty);
timeout = schedule_timeout(timeout);
continue;
}
......@@ -1885,10 +1855,8 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,