| /* |
| * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.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 "kern.h" |
| #include "irq_user.h" |
| #include "sigio.h" |
| #include "line.h" |
| #include "os.h" |
| |
| #ifdef CONFIG_NOCONFIG_CHAN |
| static void *not_configged_init(char *str, int device, |
| const struct chan_opts *opts) |
| { |
| printk("Using a channel type which is configured out of " |
| "UML\n"); |
| return NULL; |
| } |
| |
| static int not_configged_open(int input, int output, int primary, void *data, |
| char **dev_out) |
| { |
| printk("Using a channel type which is configured out of " |
| "UML\n"); |
| return -ENODEV; |
| } |
| |
| static void not_configged_close(int fd, void *data) |
| { |
| printk("Using a channel type which is configured out of " |
| "UML\n"); |
| } |
| |
| static int not_configged_read(int fd, char *c_out, void *data) |
| { |
| printk("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) |
| { |
| printk("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) |
| { |
| printk("Using a channel type which is configured out of " |
| "UML\n"); |
| return -EIO; |
| } |
| |
| static int not_configged_window_size(int fd, void *data, unsigned short *rows, |
| unsigned short *cols) |
| { |
| printk("Using a channel type which is configured out of " |
| "UML\n"); |
| return -ENODEV; |
| } |
| |
| static void not_configged_free(void *data) |
| { |
| printk("Using a channel type which is configured out of " |
| "UML\n"); |
| } |
| |
| static const struct chan_ops not_configged_ops = { |
| .init = not_configged_init, |
| .open = not_configged_open, |
| .close = not_configged_close, |
| .read = not_configged_read, |
| .write = not_configged_write, |
| .console_write = not_configged_console_write, |
| .window_size = not_configged_window_size, |
| .free = not_configged_free, |
| .winch = 0, |
| }; |
| #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; |
| |
| if(chan->opened) |
| return 0; |
| |
| 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) |
| return fd; |
| chan->fd = fd; |
| |
| chan->opened = 1; |
| return 0; |
| } |
| |
| int open_chan(struct list_head *chans) |
| { |
| struct list_head *ele; |
| struct chan *chan; |
| int ret, err = 0; |
| |
| list_for_each(ele, chans){ |
| chan = list_entry(ele, struct chan, list); |
| ret = open_one_chan(chan); |
| if(chan->primary) |
| err = ret; |
| } |
| return err; |
| } |
| |
| void chan_enable_winch(struct list_head *chans, struct tty_struct *tty) |
| { |
| struct list_head *ele; |
| struct chan *chan; |
| |
| 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; |
| } |
| } |
| } |
| |
| void enable_chan(struct line *line) |
| { |
| struct list_head *ele; |
| struct chan *chan; |
| |
| list_for_each(ele, &line->chan_list){ |
| chan = list_entry(ele, struct chan, list); |
| if(open_one_chan(chan)) |
| continue; |
| |
| if(chan->enabled) |
| continue; |
| line_setup_irq(chan->fd, chan->input, chan->output, line, |
| chan); |
| chan->enabled = 1; |
| } |
| } |
| |
| /* 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; |
| |
| spin_lock_irqsave(&irqs_to_free_lock, flags); |
| list_splice_init(&irqs_to_free, &list); |
| spin_unlock_irqrestore(&irqs_to_free_lock, flags); |
| |
| list_for_each(ele, &list){ |
| chan = list_entry(ele, struct chan, free_list); |
| |
| if(chan->input) |
| free_irq(chan->line->driver->read_irq, chan); |
| if(chan->output) |
| free_irq(chan->line->driver->write_irq, chan); |
| chan->enabled = 0; |
| } |
| } |
| |
| static void close_one_chan(struct chan *chan, int delay_free_irq) |
| { |
| unsigned long flags; |
| |
| if(!chan->opened) |
| return; |
| |
| 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); |
| chan->enabled = 0; |
| } |
| 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) |
| { |
| struct chan *chan; |
| |
| /* Close in reverse order as open in case more than one of them |
| * refers to the same device and they save and restore that device's |
| * 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); |
| } |
| } |
| |
| void deactivate_chan(struct list_head *chans, 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); |
| } |
| } |
| |
| void reactivate_chan(struct list_head *chans, 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); |
| } |
| } |
| |
| int write_chan(struct list_head *chans, 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); |
| } |
| } |
| return ret; |
| } |
| |
| int console_write_chan(struct list_head *chans, 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; |
| } |
| return ret; |
| } |
| |
| int console_open_chan(struct line *line, struct console *co) |
| { |
| int err; |
| |
| err = open_chan(&line->chan_list); |
| if(err) |
| return err; |
| |
| printk("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, |
| 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); |
| } |
| } |
| return 0; |
| } |
| |
| static void free_one_chan(struct chan *chan, int delay_free_irq) |
| { |
| list_del(&chan->list); |
| |
| close_one_chan(chan, delay_free_irq); |
| |
| if(chan->ops->free != NULL) |
| (*chan->ops->free)(chan->data); |
| |
| if(chan->primary && chan->output) ignore_sigio_fd(chan->fd); |
| kfree(chan); |
| } |
| |
| static void free_chan(struct list_head *chans, int delay_free_irq) |
| { |
| struct list_head *ele, *next; |
| struct chan *chan; |
| |
| list_for_each_safe(ele, next, chans){ |
| chan = list_entry(ele, struct chan, list); |
| free_one_chan(chan, delay_free_irq); |
| } |
| } |
| |
| static int one_chan_config_string(struct chan *chan, char *str, int size, |
| char **error_out) |
| { |
| int n = 0; |
| |
| 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){ |
| CONFIG_CHUNK(str, size, n, "", 1); |
| return n; |
| } |
| |
| CONFIG_CHUNK(str, size, n, ":", 0); |
| CONFIG_CHUNK(str, size, n, chan->dev, 0); |
| |
| return n; |
| } |
| |
| static int chan_pair_config_string(struct chan *in, struct chan *out, |
| char *str, int size, char **error_out) |
| { |
| int n; |
| |
| n = one_chan_config_string(in, str, size, error_out); |
| str += n; |
| size -= n; |
| |
| if(in == out){ |
| CONFIG_CHUNK(str, size, n, "", 1); |
| return n; |
| } |
| |
| CONFIG_CHUNK(str, size, n, ",", 1); |
| n = one_chan_config_string(out, str, size, error_out); |
| str += n; |
| size -= n; |
| CONFIG_CHUNK(str, size, n, "", 1); |
| |
| return n; |
| } |
| |
| int chan_config_string(struct list_head *chans, char *str, int size, |
| char **error_out) |
| { |
| struct list_head *ele; |
| struct chan *chan, *in = NULL, *out = NULL; |
| |
| 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; |
| } |
| |
| return chan_pair_config_string(in, out, str, size, error_out); |
| } |
| |
| struct chan_type { |
| char *key; |
| const struct chan_ops *ops; |
| }; |
| |
| static const struct chan_type chan_table[] = { |
| { "fd", &fd_ops }, |
| |
| #ifdef CONFIG_NULL_CHAN |
| { "null", &null_ops }, |
| #else |
| { "null", ¬_configged_ops }, |
| #endif |
| |
| #ifdef CONFIG_PORT_CHAN |
| { "port", &port_ops }, |
| #else |
| { "port", ¬_configged_ops }, |
| #endif |
| |
| #ifdef CONFIG_PTY_CHAN |
| { "pty", &pty_ops }, |
| { "pts", &pts_ops }, |
| #else |
| { "pty", ¬_configged_ops }, |
| { "pts", ¬_configged_ops }, |
| #endif |
| |
| #ifdef CONFIG_TTY_CHAN |
| { "tty", &tty_ops }, |
| #else |
| { "tty", ¬_configged_ops }, |
| #endif |
| |
| #ifdef CONFIG_XTERM_CHAN |
| { "xterm", &xterm_ops }, |
| #else |
| { "xterm", ¬_configged_ops }, |
| #endif |
| }; |
| |
| static struct chan *parse_chan(struct line *line, char *str, int device, |
| const struct chan_opts *opts, char **error_out) |
| { |
| 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 < ARRAY_SIZE(chan_table); i++){ |
| entry = &chan_table[i]; |
| if(!strncmp(str, entry->key, strlen(entry->key))){ |
| ops = entry->ops; |
| str += strlen(entry->key); |
| break; |
| } |
| } |
| if(ops == NULL){ |
| *error_out = "No match for configured backends"; |
| return NULL; |
| } |
| |
| data = (*ops->init)(str, device, opts); |
| if(data == NULL){ |
| *error_out = "Configuration failed"; |
| return NULL; |
| } |
| |
| chan = kmalloc(sizeof(*chan), GFP_ATOMIC); |
| 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), |
| .line = line, |
| .primary = 1, |
| .input = 0, |
| .output = 0, |
| .opened = 0, |
| .enabled = 0, |
| .fd = -1, |
| .ops = ops, |
| .data = data }); |
| return chan; |
| } |
| |
| int parse_chan_pair(char *str, struct line *line, int device, |
| const struct chan_opts *opts, char **error_out) |
| { |
| struct list_head *chans = &line->chan_list; |
| struct chan *new, *chan; |
| char *in, *out; |
| |
| if(!list_empty(chans)){ |
| chan = list_entry(chans->next, struct chan, list); |
| free_chan(chans, 0); |
| INIT_LIST_HEAD(chans); |
| } |
| |
| out = strchr(str, ','); |
| if(out != NULL){ |
| in = str; |
| *out = '\0'; |
| out++; |
| new = parse_chan(line, in, device, opts, error_out); |
| if(new == NULL) |
| return -1; |
| |
| new->input = 1; |
| list_add(&new->list, chans); |
| |
| new = parse_chan(line, out, device, opts, error_out); |
| if(new == NULL) |
| return -1; |
| |
| list_add(&new->list, chans); |
| new->output = 1; |
| } |
| else { |
| 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; |
| } |
| 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 delayed_work *task, |
| struct tty_struct *tty, int irq) |
| { |
| struct list_head *ele, *next; |
| struct chan *chan; |
| 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); |
| } |
| } |
| out: |
| if(tty) tty_flip_buffer_push(tty); |
| } |