1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2000, 2001 Jeff Dike (jdike@karaya.com) 4 */ 5 6 #include <linux/posix_types.h> 7 #include <linux/tty.h> 8 #include <linux/tty_flip.h> 9 #include <linux/types.h> 10 #include <linux/major.h> 11 #include <linux/kdev_t.h> 12 #include <linux/console.h> 13 #include <linux/string.h> 14 #include <linux/sched.h> 15 #include <linux/list.h> 16 #include <linux/init.h> 17 #include <linux/interrupt.h> 18 #include <linux/slab.h> 19 #include <linux/hardirq.h> 20 #include <asm/current.h> 21 #include <asm/irq.h> 22 #include "stdio_console.h" 23 #include "chan.h" 24 #include <irq_user.h> 25 #include "mconsole_kern.h" 26 #include <init.h> 27 28 #define MAX_TTYS (16) 29 30 static void stdio_announce(char *dev_name, int dev) 31 { 32 printk(KERN_INFO "Virtual console %d assigned device '%s'\n", dev, 33 dev_name); 34 } 35 36 /* Almost const, except that xterm_title may be changed in an initcall */ 37 static struct chan_opts opts = { 38 .announce = stdio_announce, 39 .xterm_title = "Virtual Console #%d", 40 .raw = 1, 41 }; 42 43 static int con_config(char *str, char **error_out); 44 static int con_get_config(char *dev, char *str, int size, char **error_out); 45 static int con_remove(int n, char **con_remove); 46 47 48 /* Const, except for .mc.list */ 49 static struct line_driver driver = { 50 .name = "UML console", 51 .device_name = "tty", 52 .major = TTY_MAJOR, 53 .minor_start = 0, 54 .type = TTY_DRIVER_TYPE_CONSOLE, 55 .subtype = SYSTEM_TYPE_CONSOLE, 56 .read_irq = CONSOLE_IRQ, 57 .read_irq_name = "console", 58 .write_irq = CONSOLE_WRITE_IRQ, 59 .write_irq_name = "console-write", 60 .mc = { 61 .list = LIST_HEAD_INIT(driver.mc.list), 62 .name = "con", 63 .config = con_config, 64 .get_config = con_get_config, 65 .id = line_id, 66 .remove = con_remove, 67 }, 68 }; 69 70 /* The array is initialized by line_init, at initcall time. The 71 * elements are locked individually as needed. 72 */ 73 static char *vt_conf[MAX_TTYS]; 74 static char *def_conf; 75 static struct line vts[MAX_TTYS]; 76 77 static int con_config(char *str, char **error_out) 78 { 79 return line_config(vts, ARRAY_SIZE(vts), str, &opts, error_out); 80 } 81 82 static int con_get_config(char *dev, char *str, int size, char **error_out) 83 { 84 return line_get_config(dev, vts, ARRAY_SIZE(vts), str, size, error_out); 85 } 86 87 static int con_remove(int n, char **error_out) 88 { 89 return line_remove(vts, ARRAY_SIZE(vts), n, error_out); 90 } 91 92 /* Set in an initcall, checked in an exitcall */ 93 static int con_init_done = 0; 94 95 static int con_install(struct tty_driver *driver, struct tty_struct *tty) 96 { 97 return line_install(driver, tty, &vts[tty->index]); 98 } 99 100 static const struct tty_operations console_ops = { 101 .open = line_open, 102 .install = con_install, 103 .close = line_close, 104 .write = line_write, 105 .write_room = line_write_room, 106 .chars_in_buffer = line_chars_in_buffer, 107 .flush_buffer = line_flush_buffer, 108 .flush_chars = line_flush_chars, 109 .set_termios = line_set_termios, 110 .throttle = line_throttle, 111 .unthrottle = line_unthrottle, 112 .hangup = line_hangup, 113 }; 114 115 static void uml_console_write(struct console *console, const char *string, 116 unsigned len) 117 { 118 struct line *line = &vts[console->index]; 119 unsigned long flags; 120 121 spin_lock_irqsave(&line->lock, flags); 122 console_write_chan(line->chan_out, string, len); 123 spin_unlock_irqrestore(&line->lock, flags); 124 } 125 126 static struct tty_driver *uml_console_device(struct console *c, int *index) 127 { 128 *index = c->index; 129 return driver.driver; 130 } 131 132 static int uml_console_setup(struct console *co, char *options) 133 { 134 struct line *line = &vts[co->index]; 135 136 return console_open_chan(line, co); 137 } 138 139 /* No locking for register_console call - relies on single-threaded initcalls */ 140 static struct console stdiocons = { 141 .name = "tty", 142 .write = uml_console_write, 143 .device = uml_console_device, 144 .setup = uml_console_setup, 145 .flags = CON_PRINTBUFFER|CON_ANYTIME, 146 .index = -1, 147 }; 148 149 static int stdio_init(void) 150 { 151 char *new_title; 152 int err; 153 int i; 154 155 err = register_lines(&driver, &console_ops, vts, 156 ARRAY_SIZE(vts)); 157 if (err) 158 return err; 159 160 printk(KERN_INFO "Initialized stdio console driver\n"); 161 162 new_title = add_xterm_umid(opts.xterm_title); 163 if(new_title != NULL) 164 opts.xterm_title = new_title; 165 166 for (i = 0; i < MAX_TTYS; i++) { 167 char *error; 168 char *s = vt_conf[i]; 169 if (!s) 170 s = def_conf; 171 if (!s) 172 s = i ? CONFIG_CON_CHAN : CONFIG_CON_ZERO_CHAN; 173 if (setup_one_line(vts, i, s, &opts, &error)) 174 printk(KERN_ERR "setup_one_line failed for " 175 "device %d : %s\n", i, error); 176 } 177 178 con_init_done = 1; 179 register_console(&stdiocons); 180 return 0; 181 } 182 late_initcall(stdio_init); 183 184 static void console_exit(void) 185 { 186 if (!con_init_done) 187 return; 188 close_lines(vts, ARRAY_SIZE(vts)); 189 } 190 __uml_exitcall(console_exit); 191 192 static int console_chan_setup(char *str) 193 { 194 if (!strncmp(str, "sole=", 5)) /* console= option specifies tty */ 195 return 0; 196 197 line_setup(vt_conf, MAX_TTYS, &def_conf, str, "console"); 198 return 1; 199 } 200 __setup("con", console_chan_setup); 201 __channel_help(console_chan_setup, "con"); 202