Commit 1997e9df authored by Dmitry Safonov's avatar Dmitry Safonov Committed by Greg Kroah-Hartman
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serial_core: Un-ifdef sysrq SUPPORT_SYSRQ 



The SUPPORT_SYSRQ is messy: every .c source should define it before
including "serial_core.h" if sysrq is supported or struct uart_port will
differ in sizes. Also this prevents moving to serial_core.c functions:
uart_handle_sysrq_char(), uart_prepare_sysrq_char(),
uart_unlock_and_check_sysrq().

It doesn't save many bytes in the structure, and a better way to reduce
it's size would be making rs485 and iso7816 pointers.

Introduce `has_sysrq` member to be used by serial line drivers further.

Signed-off-by: default avatarDmitry Safonov <dima@arista.com>
Link: https://lore.kernel.org/r/20191213000657.931618-4-dima@arista.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 8336240e

include/linux/serial_core.h

+43 −34
Original line number Diff line number Diff line
@@ -240,14 +240,13 @@ struct uart_port { 
	resource_size_t		mapsize;

	struct device		*dev;			/* parent device */



#if defined(CONFIG_SERIAL_CORE_CONSOLE) || defined(SUPPORT_SYSRQ)

	unsigned long		sysrq;			/* sysrq timeout */

	unsigned int		sysrq_ch;		/* char for sysrq */

#endif

	unsigned char		has_sysrq;



	unsigned char		hub6;			/* this should be in the 8250 driver */

	unsigned char		suspended;

	unsigned char		unused[2];

	unsigned char		unused;

	const char		*name;			/* port name */

	struct attribute_group	*attr_group;		/* port specific attributes */

	const struct attribute_group **tty_groups;	/* all attributes (serial core use only) */
@@ -461,31 +460,46 @@ extern void uart_handle_cts_change(struct uart_port *uport, 
extern void uart_insert_char(struct uart_port *port, unsigned int status,

		 unsigned int overrun, unsigned int ch, unsigned int flag);



#if defined(SUPPORT_SYSRQ) && defined(CONFIG_MAGIC_SYSRQ_SERIAL)

static inline int

uart_handle_sysrq_char(struct uart_port *port, unsigned int ch)

{

	if (port->sysrq) {

	if (!IS_ENABLED(CONFIG_MAGIC_SYSRQ_SERIAL))

		return 0;



	if (!port->has_sysrq && !IS_ENABLED(SUPPORT_SYSRQ))

		return 0;



	if (!port->sysrq)

		return 0;



	if (ch && time_before(jiffies, port->sysrq)) {

		handle_sysrq(ch);

		port->sysrq = 0;

		return 1;

	}

	port->sysrq = 0;

	}



	return 0;

}

static inline int

uart_prepare_sysrq_char(struct uart_port *port, unsigned int ch)

{

	if (port->sysrq) {

	if (!IS_ENABLED(CONFIG_MAGIC_SYSRQ_SERIAL))

		return 0;



	if (!port->has_sysrq && !IS_ENABLED(SUPPORT_SYSRQ))

		return 0;



	if (!port->sysrq)

		return 0;



	if (ch && time_before(jiffies, port->sysrq)) {

		port->sysrq_ch = ch;

		port->sysrq = 0;

		return 1;

	}

	port->sysrq = 0;

	}



	return 0;

}

static inline void
@@ -493,6 +507,11 @@ uart_unlock_and_check_sysrq(struct uart_port *port, unsigned long irqflags) 
{

	int sysrq_ch;



	if (!port->has_sysrq && !IS_ENABLED(SUPPORT_SYSRQ)) {

		spin_unlock_irqrestore(&port->lock, irqflags);

		return;

	}



	sysrq_ch = port->sysrq_ch;

	port->sysrq_ch = 0;
@@ -501,17 +520,6 @@ uart_unlock_and_check_sysrq(struct uart_port *port, unsigned long irqflags) 
	if (sysrq_ch)

		handle_sysrq(sysrq_ch);

}

#else

static inline int

uart_handle_sysrq_char(struct uart_port *port, unsigned int ch) { return 0; }

static inline int

uart_prepare_sysrq_char(struct uart_port *port, unsigned int ch) { return 0; }

static inline void

uart_unlock_and_check_sysrq(struct uart_port *port, unsigned long irqflags)

{

	spin_unlock_irqrestore(&port->lock, irqflags);

}

#endif



/*

 * We do the SysRQ and SAK checking like this...
@@ -523,7 +531,7 @@ static inline int uart_handle_break(struct uart_port *port) 
	if (port->handle_break)

		port->handle_break(port);



#ifdef SUPPORT_SYSRQ

	if (port->has_sysrq || IS_ENABLED(SUPPORT_SYSRQ)) {

		if (port->cons && port->cons->index == port->line) {

			if (!port->sysrq) {

				port->sysrq = jiffies + HZ*5;
@@ -531,7 +539,8 @@ static inline int uart_handle_break(struct uart_port *port) 
			}

			port->sysrq = 0;

		}

#endif

	}



	if (port->flags & UPF_SAK)

		do_SAK(state->port.tty);

	return 0;

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