From: Jeff Dike Date: Sat, 10 Feb 2007 09:44:08 +0000 (-0800) Subject: [PATCH] uml: console locking commentary and code cleanup X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=d5c9ffc6c6d15d4f655236e26942a21ad61fe3ad;p=openwrt%2Fstaging%2Fblogic.git [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: Jeff Dike Cc: Paolo 'Blaisorblade' Giarrusso Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/arch/um/drivers/line.c b/arch/um/drivers/line.c index e620ed46ed3f..433e572fb196 100644 --- a/arch/um/drivers/line.c +++ b/arch/um/drivers/line.c @@ -707,10 +707,9 @@ 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, - const struct tty_operations *ops, - struct line *lines, int nlines) +struct tty_driver *register_lines(struct line_driver *line_driver, + const struct tty_operations *ops, + struct line *lines, int nlines) { int i; struct tty_driver *driver = alloc_tty_driver(nlines); diff --git a/arch/um/drivers/ssl.c b/arch/um/drivers/ssl.c index 475de52783e4..fc22b9bd9153 100644 --- a/arch/um/drivers/ssl.c +++ b/arch/um/drivers/ssl.c @@ -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, @@ -190,9 +189,8 @@ 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, - ARRAY_SIZE(serial_lines)); + ssl_driver = register_lines(&driver, &ssl_ops, serial_lines, + ARRAY_SIZE(serial_lines)); lines_init(serial_lines, ARRAY_SIZE(serial_lines), &opts); diff --git a/arch/um/drivers/stdio_console.c b/arch/um/drivers/stdio_console.c index a83c42c263b3..8dccdd193d94 100644 --- a/arch/um/drivers/stdio_console.c +++ b/arch/um/drivers/stdio_console.c @@ -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, @@ -155,16 +154,14 @@ 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, - ARRAY_SIZE(vts)); + console_driver = register_lines(&driver, &console_ops, vts, + ARRAY_SIZE(vts)); if (console_driver == NULL) return -1; printk(KERN_INFO "Initialized stdio console driver\n"); diff --git a/arch/um/include/line.h b/arch/um/include/line.h index a2486b4cc9fe..3477a858eaa9 100644 --- a/arch/um/include/line.h +++ b/arch/um/include/line.h @@ -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, @@ -94,10 +87,9 @@ 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, - const struct tty_operations *driver, - struct line *lines, int nlines); +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); extern void close_lines(struct line *lines, int nlines);