From be10eb7589337e5defbe214dae038a53dd21add8 Mon Sep 17 00:00:00 2001 From: Paul Fulghum Date: Mon, 22 Jun 2009 18:42:56 +0100 Subject: [PATCH] tty: n_hdlc add buffer flushing Add flush_buffer tty callback to flush rx buffers. Add TCFLSH ioctl processing to flush tx buffers. Increase default tx buffers from 1 to 3. Remove unneeded flush_buffer call in open callback. Remove vendor specific CVS version string. Signed-off-by: Paul Fulghum Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds --- drivers/char/n_hdlc.c | 46 ++++++++++++++++++++++++++++++++++--------- 1 file changed, 37 insertions(+), 9 deletions(-) diff --git a/drivers/char/n_hdlc.c b/drivers/char/n_hdlc.c index 461ece591a5b..1c43c8cdee25 100644 --- a/drivers/char/n_hdlc.c +++ b/drivers/char/n_hdlc.c @@ -10,7 +10,6 @@ * Paul Mackerras * * Original release 01/11/99 - * $Id: n_hdlc.c,v 4.8 2003/05/06 21:18:51 paulkf Exp $ * * This code is released under the GNU General Public License (GPL) * @@ -79,7 +78,6 @@ */ #define HDLC_MAGIC 0x239e -#define HDLC_VERSION "$Revision: 4.8 $" #include #include @@ -114,7 +112,7 @@ #define MAX_HDLC_FRAME_SIZE 65535 #define DEFAULT_RX_BUF_COUNT 10 #define MAX_RX_BUF_COUNT 60 -#define DEFAULT_TX_BUF_COUNT 1 +#define DEFAULT_TX_BUF_COUNT 3 struct n_hdlc_buf { struct n_hdlc_buf *link; @@ -199,6 +197,31 @@ static void n_hdlc_tty_wakeup(struct tty_struct *tty); #define tty2n_hdlc(tty) ((struct n_hdlc *) ((tty)->disc_data)) #define n_hdlc2tty(n_hdlc) ((n_hdlc)->tty) +static void flush_rx_queue(struct tty_struct *tty) +{ + struct n_hdlc *n_hdlc = tty2n_hdlc(tty); + struct n_hdlc_buf *buf; + + while ((buf = n_hdlc_buf_get(&n_hdlc->rx_buf_list))) + n_hdlc_buf_put(&n_hdlc->rx_free_buf_list, buf); +} + +static void flush_tx_queue(struct tty_struct *tty) +{ + struct n_hdlc *n_hdlc = tty2n_hdlc(tty); + struct n_hdlc_buf *buf; + unsigned long flags; + + while ((buf = n_hdlc_buf_get(&n_hdlc->tx_buf_list))) + n_hdlc_buf_put(&n_hdlc->tx_free_buf_list, buf); + spin_lock_irqsave(&n_hdlc->tx_buf_list.spinlock, flags); + if (n_hdlc->tbuf) { + n_hdlc_buf_put(&n_hdlc->tx_free_buf_list, n_hdlc->tbuf); + n_hdlc->tbuf = NULL; + } + spin_unlock_irqrestore(&n_hdlc->tx_buf_list.spinlock, flags); +} + static struct tty_ldisc_ops n_hdlc_ldisc = { .owner = THIS_MODULE, .magic = TTY_LDISC_MAGIC, @@ -211,6 +234,7 @@ static struct tty_ldisc_ops n_hdlc_ldisc = { .poll = n_hdlc_tty_poll, .receive_buf = n_hdlc_tty_receive, .write_wakeup = n_hdlc_tty_wakeup, + .flush_buffer = flush_rx_queue, }; /** @@ -341,10 +365,7 @@ static int n_hdlc_tty_open (struct tty_struct *tty) set_bit(TTY_NO_WRITE_SPLIT,&tty->flags); #endif - /* Flush any pending characters in the driver and discipline. */ - if (tty->ldisc->ops->flush_buffer) - tty->ldisc->ops->flush_buffer(tty); - + /* flush receive data from driver */ tty_driver_flush_buffer(tty); if (debuglevel >= DEBUG_LEVEL_INFO) @@ -763,6 +784,14 @@ static int n_hdlc_tty_ioctl(struct tty_struct *tty, struct file *file, error = put_user(count, (int __user *)arg); break; + case TCFLSH: + switch (arg) { + case TCIOFLUSH: + case TCOFLUSH: + flush_tx_queue(tty); + } + /* fall through to default */ + default: error = n_tty_ioctl_helper(tty, file, cmd, arg); break; @@ -919,8 +948,7 @@ static struct n_hdlc_buf* n_hdlc_buf_get(struct n_hdlc_buf_list *list) } /* end of n_hdlc_buf_get() */ static char hdlc_banner[] __initdata = - KERN_INFO "HDLC line discipline: version " HDLC_VERSION - ", maxframe=%u\n"; + KERN_INFO "HDLC line discipline maxframe=%u\n"; static char hdlc_register_ok[] __initdata = KERN_INFO "N_HDLC line discipline registered.\n"; static char hdlc_register_fail[] __initdata = -- 2.20.1