diff options
Diffstat (limited to 'arch/um/drivers/chan_kern.c')
| -rw-r--r-- | arch/um/drivers/chan_kern.c | 522 |
1 files changed, 214 insertions, 308 deletions
diff --git a/arch/um/drivers/chan_kern.c b/arch/um/drivers/chan_kern.c index ab0d0b17081..acbe6c67afb 100644 --- a/arch/um/drivers/chan_kern.c +++ b/arch/um/drivers/chan_kern.c @@ -1,62 +1,20 @@ /* - * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com) + * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com) * Licensed under the GPL */ -#include <linux/stddef.h> -#include <linux/kernel.h> -#include <linux/list.h> #include <linux/slab.h> #include <linux/tty.h> -#include <linux/string.h> #include <linux/tty_flip.h> -#include <asm/irq.h> -#include "chan_kern.h" -#include "user_util.h" -#include "kern.h" -#include "irq_user.h" -#include "sigio.h" -#include "line.h" -#include "os.h" - -/* XXX: could well be moved to somewhere else, if needed. */ -static int my_printf(const char * fmt, ...) - __attribute__ ((format (printf, 1, 2))); - -static int my_printf(const char * fmt, ...) -{ - /* Yes, can be called on atomic context.*/ - char *buf = kmalloc(4096, GFP_ATOMIC); - va_list args; - int r; - - if (!buf) { - /* We print directly fmt. - * Yes, yes, yes, feel free to complain. */ - r = strlen(fmt); - } else { - va_start(args, fmt); - r = vsprintf(buf, fmt, args); - va_end(args); - fmt = buf; - } - - if (r) - r = os_write_file(1, fmt, r); - return r; - -} +#include "chan.h" +#include <os.h> +#include <irq_kern.h> #ifdef CONFIG_NOCONFIG_CHAN -/* Despite its name, there's no added trailing newline. */ -static int my_puts(const char * buf) +static void *not_configged_init(char *str, int device, + const struct chan_opts *opts) { - return os_write_file(1, buf, strlen(buf)); -} - -static void *not_configged_init(char *str, int device, struct chan_opts *opts) -{ - my_puts("Using a channel type which is configured out of " + printk(KERN_ERR "Using a channel type which is configured out of " "UML\n"); return NULL; } @@ -64,34 +22,34 @@ static void *not_configged_init(char *str, int device, struct chan_opts *opts) static int not_configged_open(int input, int output, int primary, void *data, char **dev_out) { - my_puts("Using a channel type which is configured out of " + printk(KERN_ERR "Using a channel type which is configured out of " "UML\n"); return -ENODEV; } static void not_configged_close(int fd, void *data) { - my_puts("Using a channel type which is configured out of " + printk(KERN_ERR "Using a channel type which is configured out of " "UML\n"); } static int not_configged_read(int fd, char *c_out, void *data) { - my_puts("Using a channel type which is configured out of " + printk(KERN_ERR "Using a channel type which is configured out of " "UML\n"); return -EIO; } static int not_configged_write(int fd, const char *buf, int len, void *data) { - my_puts("Using a channel type which is configured out of " + printk(KERN_ERR "Using a channel type which is configured out of " "UML\n"); return -EIO; } static int not_configged_console_write(int fd, const char *buf, int len) { - my_puts("Using a channel type which is configured out of " + printk(KERN_ERR "Using a channel type which is configured out of " "UML\n"); return -EIO; } @@ -99,18 +57,18 @@ static int not_configged_console_write(int fd, const char *buf, int len) static int not_configged_window_size(int fd, void *data, unsigned short *rows, unsigned short *cols) { - my_puts("Using a channel type which is configured out of " + printk(KERN_ERR "Using a channel type which is configured out of " "UML\n"); return -ENODEV; } static void not_configged_free(void *data) { - my_puts("Using a channel type which is configured out of " + printk(KERN_ERR "Using a channel type which is configured out of " "UML\n"); } -static struct chan_ops not_configged_ops = { +static const struct chan_ops not_configged_ops = { .init = not_configged_init, .open = not_configged_open, .close = not_configged_close, @@ -123,179 +81,154 @@ static struct chan_ops not_configged_ops = { }; #endif /* CONFIG_NOCONFIG_CHAN */ -void generic_close(int fd, void *unused) -{ - os_close_file(fd); -} - -int generic_read(int fd, char *c_out, void *unused) -{ - int n; - - n = os_read_file(fd, c_out, sizeof(*c_out)); - - if(n == -EAGAIN) - return 0; - else if(n == 0) - return -EIO; - return n; -} - -/* XXX Trivial wrapper around os_write_file */ - -int generic_write(int fd, const char *buf, int n, void *unused) -{ - return os_write_file(fd, buf, n); -} - -int generic_window_size(int fd, void *unused, unsigned short *rows_out, - unsigned short *cols_out) -{ - int rows, cols; - int ret; - - ret = os_window_size(fd, &rows, &cols); - if(ret < 0) - return ret; - - ret = ((*rows_out != rows) || (*cols_out != cols)); - - *rows_out = rows; - *cols_out = cols; - - return ret; -} - -void generic_free(void *data) -{ - kfree(data); -} - -static void tty_receive_char(struct tty_struct *tty, char ch) -{ - if(tty == NULL) return; - - if(I_IXON(tty) && !I_IXOFF(tty) && !tty->raw) { - if(ch == STOP_CHAR(tty)){ - stop_tty(tty); - return; - } - else if(ch == START_CHAR(tty)){ - start_tty(tty); - return; - } - } - - tty_insert_flip_char(tty, ch, TTY_NORMAL); -} - static int open_one_chan(struct chan *chan) { - int fd; + int fd, err; - if(chan->opened) + if (chan->opened) return 0; - if(chan->ops->open == NULL) + if (chan->ops->open == NULL) fd = 0; else fd = (*chan->ops->open)(chan->input, chan->output, chan->primary, chan->data, &chan->dev); - if(fd < 0) + if (fd < 0) return fd; + + err = os_set_fd_block(fd, 0); + if (err) { + (*chan->ops->close)(fd, chan->data); + return err; + } + chan->fd = fd; chan->opened = 1; return 0; } -int open_chan(struct list_head *chans) +static int open_chan(struct list_head *chans) { struct list_head *ele; struct chan *chan; int ret, err = 0; - list_for_each(ele, chans){ + list_for_each(ele, chans) { chan = list_entry(ele, struct chan, list); ret = open_one_chan(chan); - if(chan->primary) + if (chan->primary) err = ret; } return err; } -void chan_enable_winch(struct list_head *chans, struct tty_struct *tty) +void chan_enable_winch(struct chan *chan, struct tty_port *port) { - struct list_head *ele; - struct chan *chan; + if (chan && chan->primary && chan->ops->winch) + register_winch(chan->fd, port); +} - list_for_each(ele, chans){ - chan = list_entry(ele, struct chan, list); - if(chan->primary && chan->output && chan->ops->winch){ - register_winch(chan->fd, tty); - return; - } - } +static void line_timer_cb(struct work_struct *work) +{ + struct line *line = container_of(work, struct line, task.work); + + if (!line->throttled) + chan_interrupt(line, line->driver->read_irq); } -void enable_chan(struct line *line) +int enable_chan(struct line *line) { struct list_head *ele; struct chan *chan; + int err; - list_for_each(ele, &line->chan_list){ + INIT_DELAYED_WORK(&line->task, line_timer_cb); + + list_for_each(ele, &line->chan_list) { chan = list_entry(ele, struct chan, list); - if(open_one_chan(chan)) + err = open_one_chan(chan); + if (err) { + if (chan->primary) + goto out_close; + continue; + } - if(chan->enabled) + if (chan->enabled) continue; - line_setup_irq(chan->fd, chan->input, chan->output, line, - chan); + err = line_setup_irq(chan->fd, chan->input, chan->output, line, + chan); + if (err) + goto out_close; + chan->enabled = 1; } + + return 0; + + out_close: + close_chan(line); + return err; } +/* Items are added in IRQ context, when free_irq can't be called, and + * removed in process context, when it can. + * This handles interrupt sources which disappear, and which need to + * be permanently disabled. This is discovered in IRQ context, but + * the freeing of the IRQ must be done later. + */ +static DEFINE_SPINLOCK(irqs_to_free_lock); static LIST_HEAD(irqs_to_free); void free_irqs(void) { struct chan *chan; + LIST_HEAD(list); + struct list_head *ele; + unsigned long flags; - while(!list_empty(&irqs_to_free)){ - chan = list_entry(irqs_to_free.next, struct chan, free_list); - list_del(&chan->free_list); + spin_lock_irqsave(&irqs_to_free_lock, flags); + list_splice_init(&irqs_to_free, &list); + spin_unlock_irqrestore(&irqs_to_free_lock, flags); - if(chan->input) - free_irq(chan->line->driver->read_irq, chan); - if(chan->output) - free_irq(chan->line->driver->write_irq, chan); + list_for_each(ele, &list) { + chan = list_entry(ele, struct chan, free_list); + + if (chan->input && chan->enabled) + um_free_irq(chan->line->driver->read_irq, chan); + if (chan->output && chan->enabled) + um_free_irq(chan->line->driver->write_irq, chan); chan->enabled = 0; } } static void close_one_chan(struct chan *chan, int delay_free_irq) { - if(!chan->opened) + unsigned long flags; + + if (!chan->opened) return; - if(delay_free_irq){ + if (delay_free_irq) { + spin_lock_irqsave(&irqs_to_free_lock, flags); list_add(&chan->free_list, &irqs_to_free); + spin_unlock_irqrestore(&irqs_to_free_lock, flags); } else { - if(chan->input) - free_irq(chan->line->driver->read_irq, chan); - if(chan->output) - free_irq(chan->line->driver->write_irq, chan); + if (chan->input && chan->enabled) + um_free_irq(chan->line->driver->read_irq, chan); + if (chan->output && chan->enabled) + um_free_irq(chan->line->driver->write_irq, chan); chan->enabled = 0; } - if(chan->ops->close != NULL) + if (chan->ops->close != NULL) (*chan->ops->close)(chan->fd, chan->data); chan->opened = 0; chan->fd = -1; } -void close_chan(struct list_head *chans, int delay_free_irq) +void close_chan(struct line *line) { struct chan *chan; @@ -304,126 +237,110 @@ void close_chan(struct list_head *chans, int delay_free_irq) * state. Then, the first one opened will have the original state, * so it must be the last closed. */ - list_for_each_entry_reverse(chan, chans, list) { - close_one_chan(chan, delay_free_irq); + list_for_each_entry_reverse(chan, &line->chan_list, list) { + close_one_chan(chan, 0); } } -void deactivate_chan(struct list_head *chans, int irq) +void deactivate_chan(struct chan *chan, int irq) { - struct list_head *ele; - - struct chan *chan; - list_for_each(ele, chans) { - chan = list_entry(ele, struct chan, list); - - if(chan->enabled && chan->input) - deactivate_fd(chan->fd, irq); - } + if (chan && chan->enabled) + deactivate_fd(chan->fd, irq); } -void reactivate_chan(struct list_head *chans, int irq) +void reactivate_chan(struct chan *chan, int irq) { - struct list_head *ele; - struct chan *chan; - - list_for_each(ele, chans) { - chan = list_entry(ele, struct chan, list); - - if(chan->enabled && chan->input) - reactivate_fd(chan->fd, irq); - } + if (chan && chan->enabled) + reactivate_fd(chan->fd, irq); } -int write_chan(struct list_head *chans, const char *buf, int len, +int write_chan(struct chan *chan, const char *buf, int len, int write_irq) { - struct list_head *ele; - struct chan *chan = NULL; int n, ret = 0; - list_for_each(ele, chans) { - chan = list_entry(ele, struct chan, list); - if (!chan->output || (chan->ops->write == NULL)) - continue; - n = chan->ops->write(chan->fd, buf, len, chan->data); - if (chan->primary) { - ret = n; - if ((ret == -EAGAIN) || ((ret >= 0) && (ret < len))) - reactivate_fd(chan->fd, write_irq); - } + if (len == 0 || !chan || !chan->ops->write) + return 0; + + n = chan->ops->write(chan->fd, buf, len, chan->data); + if (chan->primary) { + ret = n; + if ((ret == -EAGAIN) || ((ret >= 0) && (ret < len))) + reactivate_fd(chan->fd, write_irq); } return ret; } -int console_write_chan(struct list_head *chans, const char *buf, int len) +int console_write_chan(struct chan *chan, const char *buf, int len) { - struct list_head *ele; - struct chan *chan; int n, ret = 0; - list_for_each(ele, chans){ - chan = list_entry(ele, struct chan, list); - if(!chan->output || (chan->ops->console_write == NULL)) - continue; - n = chan->ops->console_write(chan->fd, buf, len); - if(chan->primary) ret = n; - } + if (!chan || !chan->ops->console_write) + return 0; + + n = chan->ops->console_write(chan->fd, buf, len); + if (chan->primary) + ret = n; return ret; } -int console_open_chan(struct line *line, struct console *co, - struct chan_opts *opts) +int console_open_chan(struct line *line, struct console *co) { int err; err = open_chan(&line->chan_list); - if(err) + if (err) return err; - printk("Console initialized on /dev/%s%d\n",co->name,co->index); + printk(KERN_INFO "Console initialized on /dev/%s%d\n", co->name, + co->index); return 0; } -int chan_window_size(struct list_head *chans, unsigned short *rows_out, +int chan_window_size(struct line *line, unsigned short *rows_out, unsigned short *cols_out) { - struct list_head *ele; struct chan *chan; - list_for_each(ele, chans){ - chan = list_entry(ele, struct chan, list); - if(chan->primary){ - if(chan->ops->window_size == NULL) - return 0; - return chan->ops->window_size(chan->fd, chan->data, - rows_out, cols_out); - } + chan = line->chan_in; + if (chan && chan->primary) { + if (chan->ops->window_size == NULL) + return 0; + return chan->ops->window_size(chan->fd, chan->data, + rows_out, cols_out); + } + chan = line->chan_out; + if (chan && chan->primary) { + if (chan->ops->window_size == NULL) + return 0; + return chan->ops->window_size(chan->fd, chan->data, + rows_out, cols_out); } return 0; } -void free_one_chan(struct chan *chan, int delay_free_irq) +static void free_one_chan(struct chan *chan) { list_del(&chan->list); - close_one_chan(chan, delay_free_irq); + close_one_chan(chan, 0); - if(chan->ops->free != NULL) + if (chan->ops->free != NULL) (*chan->ops->free)(chan->data); - if(chan->primary && chan->output) ignore_sigio_fd(chan->fd); + if (chan->primary && chan->output) + ignore_sigio_fd(chan->fd); kfree(chan); } -void free_chan(struct list_head *chans, int delay_free_irq) +static void free_chan(struct list_head *chans) { struct list_head *ele, *next; struct chan *chan; - list_for_each_safe(ele, next, chans){ + list_for_each_safe(ele, next, chans) { chan = list_entry(ele, struct chan, list); - free_one_chan(chan, delay_free_irq); + free_one_chan(chan); } } @@ -432,14 +349,14 @@ static int one_chan_config_string(struct chan *chan, char *str, int size, { int n = 0; - if(chan == NULL){ + if (chan == NULL) { CONFIG_CHUNK(str, size, n, "none", 1); return n; } CONFIG_CHUNK(str, size, n, chan->ops->type, 0); - if(chan->dev == NULL){ + if (chan->dev == NULL) { CONFIG_CHUNK(str, size, n, "", 1); return n; } @@ -459,7 +376,7 @@ static int chan_pair_config_string(struct chan *in, struct chan *out, str += n; size -= n; - if(in == out){ + if (in == out) { CONFIG_CHUNK(str, size, n, "", 1); return n; } @@ -473,31 +390,25 @@ static int chan_pair_config_string(struct chan *in, struct chan *out, return n; } -int chan_config_string(struct list_head *chans, char *str, int size, +int chan_config_string(struct line *line, char *str, int size, char **error_out) { - struct list_head *ele; - struct chan *chan, *in = NULL, *out = NULL; + struct chan *in = line->chan_in, *out = line->chan_out; - list_for_each(ele, chans){ - chan = list_entry(ele, struct chan, list); - if(!chan->primary) - continue; - if(chan->input) - in = chan; - if(chan->output) - out = chan; - } + if (in && !in->primary) + in = NULL; + if (out && !out->primary) + out = NULL; return chan_pair_config_string(in, out, str, size, error_out); } struct chan_type { char *key; - struct chan_ops *ops; + const struct chan_ops *ops; }; -struct chan_type chan_table[] = { +static const struct chan_type chan_table[] = { { "fd", &fd_ops }, #ifdef CONFIG_NULL_CHAN @@ -534,38 +445,40 @@ struct chan_type chan_table[] = { }; static struct chan *parse_chan(struct line *line, char *str, int device, - struct chan_opts *opts) + const struct chan_opts *opts, char **error_out) { - struct chan_type *entry; - struct chan_ops *ops; + const struct chan_type *entry; + const struct chan_ops *ops; struct chan *chan; void *data; int i; ops = NULL; data = NULL; - for(i = 0; i < sizeof(chan_table)/sizeof(chan_table[0]); i++){ + for(i = 0; i < ARRAY_SIZE(chan_table); i++) { entry = &chan_table[i]; - if(!strncmp(str, entry->key, strlen(entry->key))){ + if (!strncmp(str, entry->key, strlen(entry->key))) { ops = entry->ops; str += strlen(entry->key); break; } } - if(ops == NULL){ - my_printf("parse_chan couldn't parse \"%s\"\n", - str); + if (ops == NULL) { + *error_out = "No match for configured backends"; return NULL; } - if(ops->init == NULL) - return NULL; + data = (*ops->init)(str, device, opts); - if(data == NULL) + if (data == NULL) { + *error_out = "Configuration failed"; return NULL; + } chan = kmalloc(sizeof(*chan), GFP_ATOMIC); - if(chan == NULL) + if (chan == NULL) { + *error_out = "Memory allocation failed"; return NULL; + } *chan = ((struct chan) { .list = LIST_HEAD_INIT(chan->list), .free_list = LIST_HEAD_INIT(chan->free_list), @@ -582,94 +495,87 @@ static struct chan *parse_chan(struct line *line, char *str, int device, } int parse_chan_pair(char *str, struct line *line, int device, - struct chan_opts *opts) + const struct chan_opts *opts, char **error_out) { struct list_head *chans = &line->chan_list; - struct chan *new, *chan; + struct chan *new; char *in, *out; - if(!list_empty(chans)){ - chan = list_entry(chans->next, struct chan, list); - free_chan(chans, 0); + if (!list_empty(chans)) { + line->chan_in = line->chan_out = NULL; + free_chan(chans); INIT_LIST_HEAD(chans); } + if (!str) + return 0; + out = strchr(str, ','); - if(out != NULL){ + if (out != NULL) { in = str; *out = '\0'; out++; - new = parse_chan(line, in, device, opts); - if(new == NULL) + new = parse_chan(line, in, device, opts, error_out); + if (new == NULL) return -1; new->input = 1; list_add(&new->list, chans); + line->chan_in = new; - new = parse_chan(line, out, device, opts); - if(new == NULL) + new = parse_chan(line, out, device, opts, error_out); + if (new == NULL) return -1; list_add(&new->list, chans); new->output = 1; + line->chan_out = new; } else { - new = parse_chan(line, str, device, opts); - if(new == NULL) + new = parse_chan(line, str, device, opts, error_out); + if (new == NULL) return -1; list_add(&new->list, chans); new->input = 1; new->output = 1; + line->chan_in = line->chan_out = new; } return 0; } -int chan_out_fd(struct list_head *chans) -{ - struct list_head *ele; - struct chan *chan; - - list_for_each(ele, chans){ - chan = list_entry(ele, struct chan, list); - if(chan->primary && chan->output) - return chan->fd; - } - return -1; -} - -void chan_interrupt(struct list_head *chans, struct work_struct *task, - struct tty_struct *tty, int irq) +void chan_interrupt(struct line *line, int irq) { - struct list_head *ele, *next; - struct chan *chan; + struct tty_port *port = &line->port; + struct chan *chan = line->chan_in; int err; char c; - list_for_each_safe(ele, next, chans){ - chan = list_entry(ele, struct chan, list); - if(!chan->input || (chan->ops->read == NULL)) continue; - do { - if (tty && !tty_buffer_request_room(tty, 1)) { - schedule_delayed_work(task, 1); - goto out; - } - err = chan->ops->read(chan->fd, &c, chan->data); - if(err > 0) - tty_receive_char(tty, c); - } while(err > 0); - - if(err == 0) reactivate_fd(chan->fd, irq); - if(err == -EIO){ - if(chan->primary){ - if(tty != NULL) - tty_hangup(tty); - close_chan(chans, 1); - return; - } - else close_one_chan(chan, 1); + if (!chan || !chan->ops->read) + goto out; + + do { + if (!tty_buffer_request_room(port, 1)) { + schedule_delayed_work(&line->task, 1); + goto out; + } + err = chan->ops->read(chan->fd, &c, chan->data); + if (err > 0) + tty_insert_flip_char(port, c, TTY_NORMAL); + } while (err > 0); + + if (err == 0) + reactivate_fd(chan->fd, irq); + if (err == -EIO) { + if (chan->primary) { + tty_port_tty_hangup(&line->port, false); + if (line->chan_out != chan) + close_one_chan(line->chan_out, 1); } + close_one_chan(chan, 1); + if (chan->primary) + return; } out: - if(tty) tty_flip_buffer_push(tty); + tty_flip_buffer_push(port); } |
