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path: root/drivers/tty/n_hdlc.c
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Diffstat (limited to 'drivers/tty/n_hdlc.c')
-rw-r--r--drivers/tty/n_hdlc.c102
1 files changed, 41 insertions, 61 deletions
diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c
index 46b09bfb6f3a..3c9dcb0928c6 100644
--- a/drivers/tty/n_hdlc.c
+++ b/drivers/tty/n_hdlc.c
@@ -109,8 +109,8 @@
struct n_hdlc_buf {
struct list_head list_item;
- int count;
- char buf[];
+ size_t count;
+ u8 buf[];
};
struct n_hdlc_buf_list {
@@ -263,25 +263,22 @@ static int n_hdlc_tty_open(struct tty_struct *tty)
*/
static void n_hdlc_send_frames(struct n_hdlc *n_hdlc, struct tty_struct *tty)
{
- register int actual;
- unsigned long flags;
struct n_hdlc_buf *tbuf;
+ ssize_t actual;
check_again:
-
- spin_lock_irqsave(&n_hdlc->tx_buf_list.spinlock, flags);
- if (n_hdlc->tbusy) {
- n_hdlc->woke_up = true;
- spin_unlock_irqrestore(&n_hdlc->tx_buf_list.spinlock, flags);
- return;
+ scoped_guard(spinlock_irqsave, &n_hdlc->tx_buf_list.spinlock) {
+ if (n_hdlc->tbusy) {
+ n_hdlc->woke_up = true;
+ return;
+ }
+ n_hdlc->tbusy = true;
+ n_hdlc->woke_up = false;
}
- n_hdlc->tbusy = true;
- n_hdlc->woke_up = false;
- spin_unlock_irqrestore(&n_hdlc->tx_buf_list.spinlock, flags);
tbuf = n_hdlc_buf_get(&n_hdlc->tx_buf_list);
while (tbuf) {
- pr_debug("sending frame %p, count=%d\n", tbuf, tbuf->count);
+ pr_debug("sending frame %p, count=%zu\n", tbuf, tbuf->count);
/* Send the next block of data to device */
set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
@@ -324,9 +321,8 @@ check_again:
clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
/* Clear the re-entry flag */
- spin_lock_irqsave(&n_hdlc->tx_buf_list.spinlock, flags);
- n_hdlc->tbusy = false;
- spin_unlock_irqrestore(&n_hdlc->tx_buf_list.spinlock, flags);
+ scoped_guard(spinlock_irqsave, &n_hdlc->tx_buf_list.spinlock)
+ n_hdlc->tbusy = false;
if (n_hdlc->woke_up)
goto check_again;
@@ -369,13 +365,13 @@ 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,
- const char *flags, int count)
+static void n_hdlc_tty_receive(struct tty_struct *tty, const u8 *data,
+ const u8 *flags, size_t count)
{
register struct n_hdlc *n_hdlc = tty->disc_data;
register struct n_hdlc_buf *buf;
- pr_debug("%s() called count=%d\n", __func__, count);
+ pr_debug("%s() called count=%zu\n", __func__, count);
if (count > maxframe) {
pr_debug("rx count>maxframesize, data discarded\n");
@@ -425,8 +421,8 @@ static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data,
* Returns the number of bytes returned or error code.
*/
static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
- __u8 *kbuf, size_t nr,
- void **cookie, unsigned long offset)
+ u8 *kbuf, size_t nr, void **cookie,
+ unsigned long offset)
{
struct n_hdlc *n_hdlc = tty->disc_data;
int ret = 0;
@@ -518,12 +514,12 @@ done_with_rbuf:
* Returns the number of bytes written (or error code).
*/
static ssize_t n_hdlc_tty_write(struct tty_struct *tty, struct file *file,
- const unsigned char *data, size_t count)
+ const u8 *data, size_t count)
{
struct n_hdlc *n_hdlc = tty->disc_data;
- int error = 0;
DECLARE_WAITQUEUE(wait, current);
struct n_hdlc_buf *tbuf;
+ ssize_t error = 0;
pr_debug("%s() called count=%zd\n", __func__, count);
@@ -584,9 +580,7 @@ static int n_hdlc_tty_ioctl(struct tty_struct *tty, unsigned int cmd,
unsigned long arg)
{
struct n_hdlc *n_hdlc = tty->disc_data;
- int error = 0;
int count;
- unsigned long flags;
struct n_hdlc_buf *buf = NULL;
pr_debug("%s() called %d\n", __func__, cmd);
@@ -595,29 +589,27 @@ static int n_hdlc_tty_ioctl(struct tty_struct *tty, unsigned int cmd,
case FIONREAD:
/* report count of read data available */
/* in next available frame (if any) */
- spin_lock_irqsave(&n_hdlc->rx_buf_list.spinlock, flags);
- buf = list_first_entry_or_null(&n_hdlc->rx_buf_list.list,
- struct n_hdlc_buf, list_item);
- if (buf)
- count = buf->count;
- else
- count = 0;
- spin_unlock_irqrestore(&n_hdlc->rx_buf_list.spinlock, flags);
- error = put_user(count, (int __user *)arg);
- break;
+ scoped_guard(spinlock_irqsave, &n_hdlc->rx_buf_list.spinlock) {
+ buf = list_first_entry_or_null(&n_hdlc->rx_buf_list.list,
+ struct n_hdlc_buf, list_item);
+ if (buf)
+ count = buf->count;
+ else
+ count = 0;
+ }
+ return put_user(count, (int __user *)arg);
case TIOCOUTQ:
/* get the pending tx byte count in the driver */
count = tty_chars_in_buffer(tty);
/* add size of next output frame in queue */
- spin_lock_irqsave(&n_hdlc->tx_buf_list.spinlock, flags);
- buf = list_first_entry_or_null(&n_hdlc->tx_buf_list.list,
- struct n_hdlc_buf, list_item);
- if (buf)
- count += buf->count;
- spin_unlock_irqrestore(&n_hdlc->tx_buf_list.spinlock, flags);
- error = put_user(count, (int __user *)arg);
- break;
+ scoped_guard(spinlock_irqsave, &n_hdlc->tx_buf_list.spinlock) {
+ buf = list_first_entry_or_null(&n_hdlc->tx_buf_list.list,
+ struct n_hdlc_buf, list_item);
+ if (buf)
+ count += buf->count;
+ }
+ return put_user(count, (int __user *)arg);
case TCFLSH:
switch (arg) {
@@ -628,11 +620,8 @@ static int n_hdlc_tty_ioctl(struct tty_struct *tty, unsigned int cmd,
fallthrough; /* to default */
default:
- error = n_tty_ioctl_helper(tty, cmd, arg);
- break;
+ return n_tty_ioctl_helper(tty, cmd, arg);
}
- return error;
-
} /* end of n_hdlc_tty_ioctl() */
/**
@@ -726,14 +715,10 @@ static struct n_hdlc *n_hdlc_alloc(void)
static void n_hdlc_buf_return(struct n_hdlc_buf_list *buf_list,
struct n_hdlc_buf *buf)
{
- unsigned long flags;
-
- spin_lock_irqsave(&buf_list->spinlock, flags);
+ guard(spinlock_irqsave)(&buf_list->spinlock);
list_add(&buf->list_item, &buf_list->list);
buf_list->count++;
-
- spin_unlock_irqrestore(&buf_list->spinlock, flags);
}
/**
@@ -744,14 +729,10 @@ static void n_hdlc_buf_return(struct n_hdlc_buf_list *buf_list,
static void n_hdlc_buf_put(struct n_hdlc_buf_list *buf_list,
struct n_hdlc_buf *buf)
{
- unsigned long flags;
-
- spin_lock_irqsave(&buf_list->spinlock, flags);
+ guard(spinlock_irqsave)(&buf_list->spinlock);
list_add_tail(&buf->list_item, &buf_list->list);
buf_list->count++;
-
- spin_unlock_irqrestore(&buf_list->spinlock, flags);
} /* end of n_hdlc_buf_put() */
/**
@@ -764,10 +745,9 @@ static void n_hdlc_buf_put(struct n_hdlc_buf_list *buf_list,
*/
static struct n_hdlc_buf *n_hdlc_buf_get(struct n_hdlc_buf_list *buf_list)
{
- unsigned long flags;
struct n_hdlc_buf *buf;
- spin_lock_irqsave(&buf_list->spinlock, flags);
+ guard(spinlock_irqsave)(&buf_list->spinlock);
buf = list_first_entry_or_null(&buf_list->list,
struct n_hdlc_buf, list_item);
@@ -776,7 +756,6 @@ static struct n_hdlc_buf *n_hdlc_buf_get(struct n_hdlc_buf_list *buf_list)
buf_list->count--;
}
- spin_unlock_irqrestore(&buf_list->spinlock, flags);
return buf;
} /* end of n_hdlc_buf_get() */
@@ -822,6 +801,7 @@ static void __exit n_hdlc_exit(void)
module_init(n_hdlc_init);
module_exit(n_hdlc_exit);
+MODULE_DESCRIPTION("HDLC line discipline support");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Paul Fulghum paulkf@microgate.com");
module_param(maxframe, int, 0);
generated by cgit (git 2.34.1) at 2025-12-21 18:36:18 +0000