Commit d5c9ffc6 authored by Jeff Dike's avatar Jeff Dike Committed by Linus Torvalds
Browse files

[PATCH] uml: console locking commentary and code cleanup 



Remove the last vestiges of devfs from console registration.  Change the name
of the function, plus remove a couple of unused fields from the line_driver
structure.

struct lines is no longer needed, all traces of it are gone.

The only way that I can see to mark a structure as being almost-const is to
individually const the fields.  This is the case for the line_driver
structure, which has only one modifiable field - a list_head in a
sub-structure.

Signed-off-by: default avatarJeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent b4ac91a0

arch/um/drivers/line.c

+3 −4
Original line number Diff line number Diff line
@@ -707,8 +707,7 @@ int line_remove(struct line *lines, unsigned int num, int n, char **error_out) 
	return err;

}



struct tty_driver *line_register_devfs(struct lines *set,

				       struct line_driver *line_driver,

struct tty_driver *register_lines(struct line_driver *line_driver,

				  const struct tty_operations *ops,

				  struct line *lines, int nlines)

{

arch/um/drivers/ssl.c

+7 −9
Original line number Diff line number Diff line
@@ -51,6 +51,8 @@ static int ssl_config(char *str, char **error_out); 
static int ssl_get_config(char *dev, char *str, int size, char **error_out);

static int ssl_remove(int n, char **error_out);





/* Const, except for .mc.list */

static struct line_driver driver = {

	.name 			= "UML serial line",

	.device_name 		= "ttyS",
@@ -62,8 +64,6 @@ static struct line_driver driver = { 
	.read_irq_name 		= "ssl",

	.write_irq 		= SSL_WRITE_IRQ,

	.write_irq_name 	= "ssl-write",

	.symlink_from 		= "serial",

	.symlink_to 		= "tts",

	.mc  = {

		.list		= LIST_HEAD_INIT(driver.mc.list),

		.name  		= "ssl",
@@ -74,14 +74,12 @@ static struct line_driver driver = { 
	},

};



/* The array is initialized by line_init, which is an initcall.  The 

 * individual elements are protected by individual semaphores.

/* The array is initialized by line_init, at initcall time.  The

 * elements are locked individually as needed.

 */

static struct line serial_lines[NR_PORTS] =

	{ [0 ... NR_PORTS - 1] = LINE_INIT(CONFIG_SSL_CHAN, &driver) };



static struct lines lines = LINES_INIT(NR_PORTS);



static int ssl_config(char *str, char **error_out)

{

	return line_config(serial_lines, ARRAY_SIZE(serial_lines), str, &opts,
@@ -175,6 +173,7 @@ static int ssl_console_setup(struct console *co, char *options) 
	return console_open_chan(line, co);

}



/* No locking for register_console call - relies on single-threaded initcalls */

static struct console ssl_cons = {

	.name		= "ttyS",

	.write		= ssl_console_write,
@@ -190,8 +189,7 @@ static int ssl_init(void) 


	printk(KERN_INFO "Initializing software serial port version %d\n",

	       ssl_version);

	ssl_driver = line_register_devfs(&lines, &driver, &ssl_ops,

					 serial_lines,

	ssl_driver = register_lines(&driver, &ssl_ops, serial_lines,

				    ARRAY_SIZE(serial_lines));



	lines_init(serial_lines, ARRAY_SIZE(serial_lines), &opts);

arch/um/drivers/stdio_console.c

+7 −10
Original line number Diff line number Diff line
@@ -55,6 +55,8 @@ static int con_config(char *str, char **error_out); 
static int con_get_config(char *dev, char *str, int size, char **error_out);

static int con_remove(int n, char **con_remove);





/* Const, except for .mc.list */

static struct line_driver driver = {

	.name 			= "UML console",

	.device_name 		= "tty",
@@ -66,8 +68,6 @@ static struct line_driver driver = { 
	.read_irq_name 		= "console",

	.write_irq 		= CONSOLE_WRITE_IRQ,

	.write_irq_name 	= "console-write",

	.symlink_from 		= "ttys",

	.symlink_to 		= "vc",

	.mc  = {

		.name  		= "con",

		.config 	= con_config,
@@ -77,10 +77,8 @@ static struct line_driver driver = { 
	},

};



static struct lines console_lines = LINES_INIT(MAX_TTYS);



/* The array is initialized by line_init, which is an initcall.  The 

 * individual elements are protected by individual semaphores.

/* The array is initialized by line_init, at initcall time.  The

 * elements are locked individually as needed.

 */

static struct line vts[MAX_TTYS] = { LINE_INIT(CONFIG_CON_ZERO_CHAN, &driver),

				     [ 1 ... MAX_TTYS - 1 ] =
@@ -148,6 +146,7 @@ static int uml_console_setup(struct console *co, char *options) 
	return console_open_chan(line, co);

}



/* No locking for register_console call - relies on single-threaded initcalls */

static struct console stdiocons = {

	.name		= "tty",

	.write		= uml_console_write,
@@ -155,15 +154,13 @@ static struct console stdiocons = { 
	.setup		= uml_console_setup,

	.flags		= CON_PRINTBUFFER,

	.index		= -1,

	.data		= &vts,

};



int stdio_init(void)

{

	char *new_title;



	console_driver = line_register_devfs(&console_lines, &driver,

					     &console_ops, vts,

	console_driver = register_lines(&driver, &console_ops, vts,

					ARRAY_SIZE(vts));

	if (console_driver == NULL)

		return -1;

arch/um/include/line.h

+14 −22
Original line number Diff line number Diff line
@@ -15,19 +15,18 @@ 
#include "chan_user.h"

#include "mconsole_kern.h"



/* There's only one modifiable field in this - .mc.list */

struct line_driver {

	char *name;

	char *device_name;

	short major;

	short minor_start;

	short type;

	short subtype;

	int read_irq;

	char *read_irq_name;

	int write_irq;

	char *write_irq_name;

	char *symlink_from;

	char *symlink_to;

	const char *name;

	const char *device_name;

	const short major;

	const short minor_start;

	const short type;

	const short subtype;

	const int read_irq;

	const char *read_irq_name;

	const int write_irq;

	const char *write_irq_name;

	struct mc_device mc;

};
@@ -67,12 +66,6 @@ struct line { 
	  .lock =	SPIN_LOCK_UNLOCKED, \

	  .driver =	d }



struct lines {

	int num;

};



#define LINES_INIT(n) {  .num =	n }



extern void line_close(struct tty_struct *tty, struct file * filp);

extern int line_open(struct line *lines, struct tty_struct *tty);

extern int line_setup(struct line *lines, unsigned int sizeof_lines,
@@ -94,8 +87,7 @@ extern char *add_xterm_umid(char *base); 
extern int line_setup_irq(int fd, int input, int output, struct line *line,

			  void *data);

extern void line_close_chan(struct line *line);

extern struct tty_driver * line_register_devfs(struct lines *set,

					       struct line_driver *line_driver,

extern struct tty_driver *register_lines(struct line_driver *line_driver,

					 const struct tty_operations *driver,

					 struct line *lines, int nlines);

extern void lines_init(struct line *lines, int nlines, struct chan_opts *opts);

CRA Git | Maintained and supported by SUSTech CRA and CCSE