/* * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com) * Licensed under the GPL */ #include <linux/slab.h> #include <linux/tty.h> #include <linux/tty_flip.h> #include "chan.h" #include <os.h> #include <irq_kern.h> #ifdef CONFIG_NOCONFIG_CHAN static void *not_configged_init(char *str, int device, const struct chan_opts *opts) { printk(KERN_ERR "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(KERN_ERR "Using a channel type which is configured out of " "UML\n"); return -ENODEV; } static void not_configged_close(int fd, void *data) { 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) { 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) { 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) { printk(KERN_ERR "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(KERN_ERR "Using a channel type which is configured out of " "UML\n"); return -ENODEV; } static void not_configged_free(void *data) { printk(KERN_ERR "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 */ static int open_one_chan(struct chan *chan) { int fd, err; 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; 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; } static 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 chan *chan, struct tty_port *port) { if (chan && chan->primary && chan->ops->winch) register_winch(chan->fd, port); } 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); } int enable_chan(struct line *line) { struct list_head *ele; struct chan *chan; int err; INIT_DELAYED_WORK(&line->task, line_timer_cb); list_for_each(ele, &line->chan_list) { chan = list_entry(ele, struct chan, list); err = open_one_chan(chan); if (err) { if (chan->primary) goto out_close; continue; } if (chan->enabled) continue; 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; 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 && 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) { 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 && 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) (*chan->ops->close)(chan->fd, chan->data); chan->opened = 0; chan->fd = -1; } void close_chan(struct line *line) { 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, &line->chan_list, list) { close_one_chan(chan, 0); } } void deactivate_chan(struct chan *chan, int irq) { if (chan && chan->enabled) deactivate_fd(chan->fd, irq); } void reactivate_chan(struct chan *chan, int irq) { if (chan && chan->enabled) reactivate_fd(chan->fd, irq); } int write_chan(struct chan *chan, const char *buf, int len, int write_irq) { int n, ret = 0; 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 chan *chan, const char *buf, int len) { int n, ret = 0; 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) { int err; err = open_chan(&line->chan_list); if (err) return err; printk(KERN_INFO "Console initialized on /dev/%s%d\n", co->name, co->index); return 0; } int chan_window_size(struct line *line, unsigned short *rows_out, unsigned short *cols_out) { struct chan *chan; 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; } static void free_one_chan(struct chan *chan) { list_del(&chan->list); close_one_chan(chan, 0); 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) { 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); } } 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 line *line, char *str, int size, char **error_out) { struct chan *in = line->chan_in, *out = line->chan_out; 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; 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; char *in, *out; 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) { 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); line->chan_in = new; 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, 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; } void chan_interrupt(struct line *line, int irq) { struct tty_port *port = &line->port; struct chan *chan = line->chan_in; int err; char c; 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: tty_flip_buffer_push(port); }