Commit 4d0e56d5 authored by Jiri Slaby (SUSE)'s avatar Jiri Slaby (SUSE) Committed by Greg Kroah-Hartman
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tty: serial: get rid of exit label from uart_set_info() 



The label is unneeded since 7ba2e769 (tty: Split the serial_core
helpers for setserial into two). Until then, there was a lock held in
uart_set_info().

Now it is not, so we can remove the label. This involves reordering the
code, so that it is clear what values are returned, where and why. Until
now, it was really hard to follow.

The "change_port" part of the function is extracted into a separate
function in the next patch. This patch makes the transition there easier
too.

Signed-off-by: default avatarJiri Slaby (SUSE) <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20241211074933.92973-3-jirislaby@kernel.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent e52ed2dd

drivers/tty/serial/serial_core.c

+51 −65
Original line number Diff line number Diff line
@@ -843,7 +843,7 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port, 
	unsigned int change_irq, change_port, closing_wait;

	unsigned int old_custom_divisor, close_delay;

	upf_t old_flags, new_flags;

	int retval = 0;

	int retval;



	if (!uport)

		return -EIO;
@@ -882,13 +882,10 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port, 
	if (!(uport->flags & UPF_FIXED_PORT)) {

		unsigned int uartclk = new_info->baud_base * 16;

		/* check needs to be done here before other settings made */

		if (uartclk == 0) {

			retval = -EINVAL;

			goto exit;

		}

		if (uartclk == 0)

			return -EINVAL;

	}

	if (!capable(CAP_SYS_ADMIN)) {

		retval = -EPERM;

		if (change_irq || change_port ||

		    (new_info->baud_base != uport->uartclk / 16) ||

		    (close_delay != port->close_delay) ||
@@ -896,7 +893,7 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port, 
		    (new_info->xmit_fifo_size &&

		     new_info->xmit_fifo_size != uport->fifosize) ||

		    (((new_flags ^ old_flags) & ~UPF_USR_MASK) != 0))

			goto exit;

			return -EPERM;

		uport->flags = ((uport->flags & ~UPF_USR_MASK) |

			       (new_flags & UPF_USR_MASK));

		uport->custom_divisor = new_info->custom_divisor;
@@ -906,30 +903,24 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port, 
	if (change_irq || change_port) {

		retval = security_locked_down(LOCKDOWN_TIOCSSERIAL);

		if (retval)

			goto exit;

			return retval;

	}



	/*

	 * Ask the low level driver to verify the settings.

	 */

	if (uport->ops->verify_port)

	 /* Ask the low level driver to verify the settings. */

	if (uport->ops->verify_port) {

		retval = uport->ops->verify_port(uport, new_info);

		if (retval)

			return retval;

	}



	if ((new_info->irq >= irq_get_nr_irqs()) || (new_info->irq < 0) ||

	    (new_info->baud_base < 9600))

		retval = -EINVAL;



	if (retval)

		goto exit;

		return -EINVAL;



	if (change_port || change_irq) {

		retval = -EBUSY;



		/*

		 * Make sure that we are the sole user of this port.

		 */

		 /* Make sure that we are the sole user of this port. */

		if (tty_port_users(port) > 1)

			goto exit;

			return -EBUSY;



		/*

		 * We need to shutdown the serial port at the old
@@ -967,11 +958,6 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port, 
		 */

		if (uport->type != PORT_UNKNOWN && uport->ops->request_port) {

			retval = uport->ops->request_port(uport);

		} else {

			/* Always success - Jean II */

			retval = 0;

		}



			/*

			 * If we fail to request resources for the

			 * new port, try to restore the old settings.
@@ -987,20 +973,18 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port, 
				if (old_type != PORT_UNKNOWN) {

					retval = uport->ops->request_port(uport);

					/*

				 * If we failed to restore the old settings,

				 * we fail like this.

					 * If we failed to restore the old

					 * settings, we fail like this.

					 */

					if (retval)

						uport->type = PORT_UNKNOWN;



				/*

				 * We failed anyway.

				 */

				retval = -EBUSY;

					/* We failed anyway. */

					return -EBUSY;

				}



			/* Added to return the correct error -Ram Gupta */

			goto exit;

				return retval;

			}

		}

	}
@@ -1017,9 +1001,9 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port, 
		uport->fifosize = new_info->xmit_fifo_size;



 check_and_exit:

	retval = 0;

	if (uport->type == PORT_UNKNOWN)

		goto exit;

		return 0;



	if (tty_port_initialized(port)) {

		if (((old_flags ^ uport->flags) & UPF_SPD_MASK) ||

		    old_custom_divisor != uport->custom_divisor) {
@@ -1035,15 +1019,17 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port, 
			}

			uart_change_line_settings(tty, state, NULL);

		}

	} else {



		return 0;

	}



	retval = uart_startup(tty, state, true);

	if (retval < 0)

		return retval;

	if (retval == 0)

		tty_port_set_initialized(port, true);

		if (retval > 0)

			retval = 0;

	}

 exit:

	return retval;



	return 0;

}



static int uart_set_info_user(struct tty_struct *tty, struct serial_struct *ss)