v4.19.13 snapshot.
diff --git a/arch/um/drivers/chan_kern.c b/arch/um/drivers/chan_kern.c
new file mode 100644
index 0000000..05588f9
--- /dev/null
+++ b/arch/um/drivers/chan_kern.c
@@ -0,0 +1,544 @@
+/*
+ * 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;
+}
+
+static void close_one_chan(struct chan *chan, int delay_free_irq)
+{
+ if (!chan->opened)
+ return;
+
+ /* we can safely call free now - it will be marked
+ * as free and freed once the IRQ stopped processing
+ */
+ 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);
+}