diff options
| -rw-r--r-- | drivers/tty/vcc.c | 101 |
1 files changed, 98 insertions, 3 deletions
diff --git a/drivers/tty/vcc.c b/drivers/tty/vcc.c index 67be5a57c1b5..0c0fe228546b 100644 --- a/drivers/tty/vcc.c +++ b/drivers/tty/vcc.c @@ -844,10 +844,105 @@ static void vcc_hangup(struct tty_struct *tty) tty_port_hangup(tty->port); } +static int vcc_write(struct tty_struct *tty, const unsigned char *buf, + int count) +{ + struct vcc_port *port; + struct vio_vcc *pkt; + unsigned long flags; + int total_sent = 0; + int tosend = 0; + int rv = -EINVAL; + + if (unlikely(!tty)) { + pr_err("VCC: write: Invalid TTY handle\n"); + return -ENXIO; + } + + port = vcc_get_ne(tty->index); + if (unlikely(!port)) { + pr_err("VCC: write: Failed to find VCC port"); + return -ENODEV; + } + + spin_lock_irqsave(&port->lock, flags); + + pkt = &port->buffer; + pkt->tag.type = VIO_TYPE_DATA; + + while (count > 0) { + /* Minimum of data to write and space available */ + tosend = min(count, (VCC_BUFF_LEN - port->chars_in_buffer)); + + if (!tosend) + break; + + memcpy(&pkt->data[port->chars_in_buffer], &buf[total_sent], + tosend); + port->chars_in_buffer += tosend; + pkt->tag.stype = tosend; + + vccdbg("TAG [%02x:%02x:%04x:%08x]\n", pkt->tag.type, + pkt->tag.stype, pkt->tag.stype_env, pkt->tag.sid); + vccdbg("DATA [%s]\n", pkt->data); + vccdbgl(port->vio.lp); + + /* Since we know we have enough room in VCC buffer for tosend + * we record that it was sent regardless of whether the + * hypervisor actually took it because we have it buffered. + */ + rv = ldc_write(port->vio.lp, pkt, (VIO_TAG_SIZE + tosend)); + vccdbg("VCC: write: ldc_write(%d)=%d\n", + (VIO_TAG_SIZE + tosend), rv); + + total_sent += tosend; + count -= tosend; + if (rv < 0) { + vcc_kick_tx(port); + break; + } + + port->chars_in_buffer = 0; + } + + spin_unlock_irqrestore(&port->lock, flags); + + vcc_put(port, false); + + vccdbg("VCC: write: total=%d rv=%d", total_sent, rv); + + return total_sent ? total_sent : rv; +} + +static int vcc_write_room(struct tty_struct *tty) +{ + struct vcc_port *port; + u64 num; + + if (unlikely(!tty)) { + pr_err("VCC: write_room: Invalid TTY handle\n"); + return -ENXIO; + } + + port = vcc_get_ne(tty->index); + if (unlikely(!port)) { + pr_err("VCC: write_room: Failed to find VCC port\n"); + return -ENODEV; + } + + num = VCC_BUFF_LEN - port->chars_in_buffer; + + vcc_put(port, false); + + return num; +} + static const struct tty_operations vcc_ops = { - .open = vcc_open, - .close = vcc_close, - .hangup = vcc_hangup, + .open = vcc_open, + .close = vcc_close, + .hangup = vcc_hangup, + .write = vcc_write, + .write_room = vcc_write_room, }; #define VCC_TTY_FLAGS (TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_REAL_RAW) |