diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-06-10 05:30:17 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2016-06-10 05:30:17 -0300 |
commit | d635711daa98be86d4c7fd01499c34f566b54ccb (patch) | |
tree | aa5cc3760a27c3d57146498cb82fa549547de06c /drivers/tty/tty_buffer.c | |
parent | c91265cd0efb83778f015b4d4b1129bd2cfd075e (diff) |
Linux-libre 4.6.2-gnu
Diffstat (limited to 'drivers/tty/tty_buffer.c')
-rw-r--r-- | drivers/tty/tty_buffer.c | 73 |
1 files changed, 34 insertions, 39 deletions
diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c index 3cd31e0d4..aa80dc94d 100644 --- a/drivers/tty/tty_buffer.c +++ b/drivers/tty/tty_buffer.c @@ -37,29 +37,6 @@ #define TTY_BUFFER_PAGE (((PAGE_SIZE - sizeof(struct tty_buffer)) / 2) & ~0xFF) -/* - * If all tty flip buffers have been processed by flush_to_ldisc() or - * dropped by tty_buffer_flush(), check if the linked pty has been closed. - * If so, wake the reader/poll to process - */ -static inline void check_other_closed(struct tty_struct *tty) -{ - unsigned long flags, old; - - /* transition from TTY_OTHER_CLOSED => TTY_OTHER_DONE must be atomic */ - for (flags = ACCESS_ONCE(tty->flags); - test_bit(TTY_OTHER_CLOSED, &flags); - ) { - old = flags; - __set_bit(TTY_OTHER_DONE, &flags); - flags = cmpxchg(&tty->flags, old, flags); - if (old == flags) { - wake_up_interruptible(&tty->read_wait); - break; - } - } -} - /** * tty_buffer_lock_exclusive - gain exclusive access to buffer * tty_buffer_unlock_exclusive - release exclusive access @@ -254,8 +231,6 @@ void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld) if (ld && ld->ops->flush_buffer) ld->ops->flush_buffer(tty); - check_other_closed(tty); - atomic_dec(&buf->priority); mutex_unlock(&buf->lock); } @@ -435,25 +410,42 @@ int tty_prepare_flip_string(struct tty_port *port, unsigned char **chars, } EXPORT_SYMBOL_GPL(tty_prepare_flip_string); +/** + * tty_ldisc_receive_buf - forward data to line discipline + * @ld: line discipline to process input + * @p: char buffer + * @f: TTY_* flags buffer + * @count: number of bytes to process + * + * Callers other than flush_to_ldisc() need to exclude the kworker + * from concurrent use of the line discipline, see paste_selection(). + * + * Returns the number of bytes not processed + */ +int tty_ldisc_receive_buf(struct tty_ldisc *ld, unsigned char *p, + char *f, int count) +{ + if (ld->ops->receive_buf2) + count = ld->ops->receive_buf2(ld->tty, p, f, count); + else { + count = min_t(int, count, ld->tty->receive_room); + if (count && ld->ops->receive_buf) + ld->ops->receive_buf(ld->tty, p, f, count); + } + return count; +} +EXPORT_SYMBOL_GPL(tty_ldisc_receive_buf); static int -receive_buf(struct tty_struct *tty, struct tty_buffer *head, int count) +receive_buf(struct tty_ldisc *ld, struct tty_buffer *head, int count) { - struct tty_ldisc *disc = tty->ldisc; unsigned char *p = char_buf_ptr(head, head->read); char *f = NULL; if (~head->flags & TTYB_NORMAL) f = flag_buf_ptr(head, head->read); - if (disc->ops->receive_buf2) - count = disc->ops->receive_buf2(tty, p, f, count); - else { - count = min_t(int, count, tty->receive_room); - if (count && disc->ops->receive_buf) - disc->ops->receive_buf(tty, p, f, count); - } - return count; + return tty_ldisc_receive_buf(ld, p, f, count); } /** @@ -505,16 +497,14 @@ static void flush_to_ldisc(struct work_struct *work) */ count = smp_load_acquire(&head->commit) - head->read; if (!count) { - if (next == NULL) { - check_other_closed(tty); + if (next == NULL) break; - } buf->head = next; tty_buffer_free(port, head); continue; } - count = receive_buf(tty, head, count); + count = receive_buf(disc, head, count); if (!count) break; head->read += count; @@ -597,3 +587,8 @@ bool tty_buffer_cancel_work(struct tty_port *port) { return cancel_work_sync(&port->buf.work); } + +void tty_buffer_flush_work(struct tty_port *port) +{ + flush_work(&port->buf.work); +} |