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path: root/drivers/tty/n_tty.c
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Diffstat (limited to 'drivers/tty/n_tty.c')
-rw-r--r--drivers/tty/n_tty.c27
1 files changed, 19 insertions, 8 deletions
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index 7cdd1eb9406c..34aacaaae14a 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -93,6 +93,7 @@ struct n_tty_data {
size_t canon_head;
size_t echo_head;
size_t echo_commit;
+ size_t echo_mark;
DECLARE_BITMAP(char_map, 256);
/* private to n_tty_receive_overrun (single-threaded) */
@@ -336,6 +337,7 @@ static void reset_buffer_flags(struct n_tty_data *ldata)
{
ldata->read_head = ldata->canon_head = ldata->read_tail = 0;
ldata->echo_head = ldata->echo_tail = ldata->echo_commit = 0;
+ ldata->echo_mark = 0;
ldata->line_start = 0;
ldata->erasing = 0;
@@ -768,7 +770,7 @@ static size_t __process_echoes(struct tty_struct *tty)
* data at the tail to prevent a subsequent overrun */
while (ldata->echo_commit - tail >= ECHO_DISCARD_WATERMARK) {
if (echo_buf(ldata, tail) == ECHO_OP_START) {
- if (echo_buf(ldata, tail) == ECHO_OP_ERASE_TAB)
+ if (echo_buf(ldata, tail + 1) == ECHO_OP_ERASE_TAB)
tail += 3;
else
tail += 2;
@@ -787,6 +789,7 @@ static void commit_echoes(struct tty_struct *tty)
size_t head;
head = ldata->echo_head;
+ ldata->echo_mark = head;
old = ldata->echo_commit - ldata->echo_tail;
/* Process committed echoes if the accumulated # of bytes
@@ -810,10 +813,12 @@ static void process_echoes(struct tty_struct *tty)
struct n_tty_data *ldata = tty->disc_data;
size_t echoed;
- if (!L_ECHO(tty) || ldata->echo_commit == ldata->echo_tail)
+ if ((!L_ECHO(tty) && !L_ECHONL(tty)) ||
+ ldata->echo_mark == ldata->echo_tail)
return;
mutex_lock(&ldata->output_lock);
+ ldata->echo_commit = ldata->echo_mark;
echoed = __process_echoes(tty);
mutex_unlock(&ldata->output_lock);
@@ -821,11 +826,13 @@ static void process_echoes(struct tty_struct *tty)
tty->ops->flush_chars(tty);
}
+/* NB: echo_mark and echo_head should be equivalent here */
static void flush_echoes(struct tty_struct *tty)
{
struct n_tty_data *ldata = tty->disc_data;
- if (!L_ECHO(tty) || ldata->echo_commit == ldata->echo_head)
+ if ((!L_ECHO(tty) && !L_ECHONL(tty)) ||
+ ldata->echo_commit == ldata->echo_head)
return;
mutex_lock(&ldata->output_lock);
@@ -1998,7 +2005,10 @@ static int canon_copy_from_read_buf(struct tty_struct *tty,
found = 1;
size = N_TTY_BUF_SIZE - tail;
- n = (found + eol + size) & (N_TTY_BUF_SIZE - 1);
+ n = eol - tail;
+ if (n > 4096)
+ n += 4096;
+ n += found;
c = n;
if (found && read_buf(ldata, eol) == __DISABLED_CHAR) {
@@ -2243,18 +2253,19 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
if (time)
timeout = time;
}
- mutex_unlock(&ldata->atomic_read_lock);
- remove_wait_queue(&tty->read_wait, &wait);
+ n_tty_set_room(tty);
+ up_read(&tty->termios_rwsem);
+ remove_wait_queue(&tty->read_wait, &wait);
if (!waitqueue_active(&tty->read_wait))
ldata->minimum_to_wake = minimum;
+ mutex_unlock(&ldata->atomic_read_lock);
+
__set_current_state(TASK_RUNNING);
if (b - buf)
retval = b - buf;
- n_tty_set_room(tty);
- up_read(&tty->termios_rwsem);
return retval;
}